#### Results in Journal Journal of Biomedical Science and Engineering: 1,167

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M. N. P. Vidal, J. M. Granjeiro
Published: 1 January 2017
Journal of Biomedical Science and Engineering, Volume 10, pp 431-443; https://doi.org/10.4236/jbise.2017.109033

Abstract:
The risks and damages related to the use of products, technologies and services of sanitary interest can be due to defects or manufacturing failures. Certain products already contain a certain degree of risk, which requires strict quality control in their production, distribution and use, as well as in the disposal of their waste in the environment. With continuous development in science and technology, medical devices must undergo intradermal irritation and testing for sensitization, cytotoxicity, and acute systemic toxicity. In health care, biotechnology aims to provide technology-based products or processes related to energy, food, and health, which are capable of stimulating new businesses, expanding exports, integrating the value chain and stimulating new demands for innovative products and processes, taking into account health policies. The present article was prepared by a bibliographical survey of the electronic databases PubMed, Lilacs, and Bireme. Cell culture testing can be successfully employed, as it is reproducible, rapid, sensitive, and financially accessible for performing in vitro toxicity testing. Thus, it has been possible to optimize the development phase of new products by decreasing animal use or even replacing them in certain tests. Some in vitro assays validated by the Organization for Economic Cooperation and Development in the area of health products have already replaced animal testing.
Felipe Pablo Perez, Joseph Paul Bandeira, Jorge J. Morisaki, Seshasai Vamsi Krishna Peddinti, Paul Salama, James Rizkalla, Maher E. Rizkalla
Published: 1 January 2017
Journal of Biomedical Science and Engineering, Volume 10, pp 421-430; https://doi.org/10.4236/jbise.2017.109032

Abstract:
Background: The rapid development of a variety of devices that emit Radiofrequency Electromagnetic fields (RF-EMF) has sparked growing interest in their interaction with biological systems and the beneficial effects on human health. As a result, investigations have been driven by the potential for therapeutic applications, as well as concern for any possible negative health implications of these EM energies [1-4]. Recent results have indicated specific tuning of experimental and clinical RF exposure may lead to their clinical application toward beneficial health outcomes [5]. Method: In the current study, a mathematical and computer simulation model to analyze a specific RF-EMF exposure on a human head model was developed. Impetus for this research was derived from results of our previous experiments which revealed that Repeated Electromagnetic Field Stimulation (REMFS) decreased the toxic levels of beta amyloid (Aβ) in neuronal cells, thereby suggesting a new potential therapeutic strategy for the treatment of Alzheimer’s disease (AD). Throughout development of the proposed device, experimental variables such as the EM frequency range, specific absorption rate (SAR), penetration depth, and innate properties of different tissues have been carefully considered. Results: RF-EMF exposure to the human head phantom was performed utilizing a Yagi-Uda antenna type possessing high gain (in the order of 10 dbs) at a frequency of 64 MHz and SAR of 0.6 W/Kg. In order to maximize the EM power transmission in one direction, directors were placed in front of the driven element and reflectors were placed behind the driven element. So as to strategically direct the EM field into the center of the brain tissue, while providing field linearity, our analysis considered the field distribution for one versus four antennas. Within the provided dimensions of a typical human brain, results of the Bioheat equation within COMSOL Multiphysics version 5.2a software demonstrated less than a 1 m°K increase from the absorbed EM power.
Nankang G. Lepzem, Rachel Adetoro Togun
Published: 1 January 2017
Journal of Biomedical Science and Engineering, Volume 10, pp 402-420; https://doi.org/10.4236/jbise.2017.108031

Abstract:
Methanolic extracts of Tetracarpidium conophorum (TCME) leaf, seed or leaf + seed extract demonstrated high capacity for reversing hyperglycemia and oxidative stress comparable with the standard anti-diabetic drug, metformin, in alloxan-induced diabetic rats. The leaf + seed extracts showed the best activity among the extracts and also ameliorated oxidative stress-induced damage of pancreas and liver tissue to normal state.
Dau Phan, Ngoc Giang Nguyen, Favorisen Rosyking Lumbanraja, , Bahriddin Abapihi, Bedy Purnama, Mera Kartika Delimayanti, Mamoru Kubo, Kenji Satou
Published: 1 January 2017
Journal of Biomedical Science and Engineering, Volume 10, pp 390-401; https://doi.org/10.4236/jbise.2017.108030

Abstract:
To classify DNA sequences, k-mer frequency is widely used since it can convert variable-length sequences into fixed-length and numerical feature vectors. However, in case of fixed-length DNA sequence classification, subsequences starting at a specific position of the given sequence can also be used as categorical features. Through the performance evaluation on six datasets of fixed-length DNA sequences, our algorithm based on the above idea achieved comparable or better performance than other state-of-the art algorithms.
Jean Espoir E. Vokwely, Jean Valentin F. Fokouo, Guy Merlin Ngounou, Dalil Asmaou, Esthelle G. Minka Ngom, Martin Kom, Richard L. Njock, G. Bengono, Alexis Ndjolo
Published: 1 January 2017
Journal of Biomedical Science and Engineering, Volume 10, pp 376-389; https://doi.org/10.4236/jbise.2017.108029

Abstract:
Background: There is a huge gap in the audiological care in Africa by comparison with Western countries. Its main reason is the prohibitive cost of the medical devices used to screen or diagnose patients. A Cameroonian team tackled this problem by developing a medical device (SON’OR©) which integrates a new instrumentation amplifier structure dedicated to perform otoacoustic emissions (OAE) and brainstem evoked response audiometry (BERA). The major technical challenges to perform OAE and BERA are the synchronization and the amplification of signals of very low amplitude. In this work, we emphasize on the general criteria necessary and indispensable to achieve an optimal amplification. The application of a novel instrumentation amplifier structure characterized by its optimized noise factor in the case of BERA and OEA emissions provides simulations and experimental results fully in line with forecasts. The design of SON’OR© is based on general techniques of electronic instrumentation to which we associated the new instrumentation amplifier structure. Objective: To report the clinical evaluation of SON’OR© as a screening and diagnostic tool. Methods: We conducted a cross sectional comparative study in Centre Hospitalier d’Essos in Yaoundé. We tested SON’OR© on two sets of subjects, one for OAE with OTODYNAMICS Echoport ILO 292-II as gold standard and the other for BERA with NEUROSOFT NEURO AUDIO© as gold standard. Each patient was tested with both devices and then we studied the inter device differences and calculated the sensitivity, specificity, positive predictive value and negative predictive value for each test. Results: We got 52 subjects for OEA and 51 for BERA testing. Sex ratio was 1 woman for 2 men in both groups. Mean age was 24.86(SD = 10.53) and 26.33 (10.55) for OAE and BERA groups respectively. SON’OR© had good performances, showing sensitivity of 92.85%/95%, specificity of 96.77%/90.47%, positive predictive value of 95.21%/93.44% and negative predictive value of 95.23%/92.68% for OAE/ BERA respectively. Conclusion: SON’OR© has good characteristics as a medical diagnostic tool. Furthermore its stability and performances in poor electrical conditions make it a robust device really suited for resource limited settings.
, Britta Göbel, , , Andreas Moser
Published: 1 January 2011
Journal of Biomedical Science and Engineering, Volume 04, pp 136-145; https://doi.org/10.4236/jbise.2011.42020

Abstract:
In this work, we specify potential elements of the brain to sense and regulate the energy metabolism of the organism. Our numerical investigations base on neurochemical experiments demonstrating a biphasic association between brain glucose level and neuronal activity. The dynamics of high and low affine KATP channels are most likely to play a decisive role in neuronal activity. We develop a coupled Hodgkin-Huxley model describing the interactive behavior of inhibitory GABAergic and excitatory dopaminergic neurons projecting into the caudate nucleus. The novelty in our approach is that we include the synaptic coupling of GABAergic and dopaminergic neurons as well as the interaction of high and low affine KATP channels. Both are crucial mechanisms described by kinetic models. Simulations demonstrate that our new model is coherent with neurochemical in vitro experiments. Even experimental interventions with glibenclamide and glucosamine are reproduced by our new model. Our results show that the considered dynamics of high and low affine KATP channels may be a driving force in energy sensing and global regulation of the energy metabolism, which supports central aspects of the new Selfish Brain Theory. Moreover, our simulations suggest that firing frequencies and patterns of GABAergic and dopaminergic neurons are correlated to their neurochemical outflow
, Kun Wang, Li-Hua Lu, Kang-Ning Xie, Qiao-Ling Xu, Xiao-Ming Wu, Chi Tang,
Published: 1 January 2011
Journal of Biomedical Science and Engineering, Volume 04, pp 130-135; https://doi.org/10.4236/jbise.2011.42019

Abstract:
Many people who live in the low altitude areas are often suffered from hypoxia when they entered the high plateau. This problem may seriously influence the physical and mental state and work efficacy for the travelers and workers. Oxygen enrichment of a small space air at high altitude is considered as a simple way to provide lowlanders enriched oxygen for sleeping and resting, improving work efficiency, so we developed an oxygen concentration machine based on the technology of oxygen enrichment membrane. This paper tested 8 healthy male lowlanders (age 21.63±1.77 yr) who have never exposed to plateau performed an incremental exercise on cycle ergometer at sea-level in order to be used as sea-level controls. Two days later, the same subjects were taken to Lhasa (3700 m) by air and exposed to the plateau, performed the same exercise as they did at sea-level. The next day, all subjects were asked to enter the experimental tent which was enriched with oxygen (higher than 24%) by the oxygen concentration machine and sleep for 10 hours at night, then exposed to plateau and performed the same exercise twice at different time (2 hours and 10 hours after oxygen enrichment). During the tests, subjects must cycled continuously at 60 rpm beginning with a 3 min exercise intensity of 0 W followed by incremental increases of 25 W every 3 min until 150 W, pulse oxygen saturation (SpO2) and heart rate (HR) were recorded. After sleeping in an oxygen enrichment of tent air, 2 hours later, the subjects’ load capacity had no difference compared with control group, but significant difference than before (higher SpO2 and lower HR), which indicated that oxygen concentration machine is effective in increasing the oxygen concentration of the air for the tent and sleeping in the oxygen enrichment tent for l0 h might be effective in improving exercise performance during high-altitude hypoxia. At the same time, 10 hours later, when work-load exceeded 125 W, the same effects were also found. The results indicated the effects of oxygen enrichment of tent air could last a certain period of time
Jia-Jung Wang, , Tsiar Kao, Chun-Peng Liu, Shih-Kai Lin
Published: 1 January 2011
Journal of Biomedical Science and Engineering, Volume 04, pp 122-129; https://doi.org/10.4236/jbise.2011.42018

Abstract:
It is essential to continuously and non-invasively monitor the cardiac pumping function in clinical setting. Thus, the study aimed to explore a regional impedance phethysmographic method to assess the changes in stroke volume. To do this, we developed a plethysmographic device that was capable of delivering a single-frequency current with constant amplitude and of recording electrical impedance signals of biological tissue. The electrical impedance plethy- smographic waveform form the lower arm was measured with the impedance plethysmographic device, and simultaneously the end-systolic and end- diastolic volumes of the left ventricle were obtained with a two-dimension echocardiographic system in fourteen healthy subjects before and immediately after a thirty-second breath-hold maneuver. For the 14 subjects, a linear correlation coefficient of 0.79 (p < 0.001) was obtained between the changes in peak amplitude of the forearm impedance waveform and the changes in stroke volume before and just after the breath-hold test. In addition, the changes in the mean area under the impedance curve and the change in stroke volume were also correlated linearly (r = 0.71, p < 0.005). In summary, the forearm impedance plethysmography may be employed to evaluate the beat-to-beat alteration in cardiac stroke volume, suggesting its potential for long-term monitoring cardiac pumping performance
Zheng Li
Published: 1 January 2011
Journal of Biomedical Science and Engineering, Volume 04, pp 119-121; https://doi.org/10.4236/jbise.2011.42017

Abstract:
This paper describes the recent research and development of an endo surgical/biomedical instrument in surgical suture applications for minimally invasive therapy procedure. The newly developed instruments can not only protect the wound during the surgical procedure but also actively help the healing process. The new mechanism design of the surgical instrument aids in better ergonomic design, reliable functionality, and continuous cost reduction in product manufacturing. 3-D modeling technique, functionality analysis, kinematical simulation and computer aided solution have been applied to the instrument design, development and future improvement to meet the specific requirements of minimally invasive surgery procedure. The improved new endo surgical/biomedical instrument can prevent patient’s vessels and tissues from being damaging because the distal move of clips are well controlled without clip drop-off incident. Plus the operational force to form the clip is lower than regular surgical/biomedical instruments due to this special new mechanism design. In addition to the above, the manufacturing and product cost can be decreased because the dimensional tolerance of components, such as clip channel and jaw guide track, can be loose due to this new instrument design. The prototypes of this new endo surgical/biomedical instrument design are analyzed through computer aided modeling and simulation, in order to prove its feasible functionality, reliable performance, and mechanical advantage. All these improved features have also been tested and verified through the prototypes
Laurent Lemaire, François Seguin, , Delphine Bon, Anne Pasco, Nadège Boildieu, Jean-Jacques Le Jeune
Published: 1 January 2011
Journal of Biomedical Science and Engineering, Volume 04, pp 110-118; https://doi.org/10.4236/jbise.2011.42016

Abstract:
Lien vers l'éditeur :http://www.scirp.org/journal/jbise/International audienceExperimental models of traumatic brain injury (TBI) provide a useful tool for understanding the cerebral metabolic changes induced by this pathological con-dition. Here, we report on the time course of changes in cerebral metabolites after TBI using high-resolution proton magnetic resonance spectros-copy (NMR). Extracts from adult male Spra-gue-Dawley rats were subjected to fluid lateral per-cussion were examined by NMR at 3, 24 and 48h af-ter the injury. A metabolomic approach was carried out to identify the cerebral metabolites impacted by the TBI and their quantitative temporal changes. Lactate, valine and ascorbate were the three first metabolites to be significantly modified after TBI. The quantitative elevation for these compounds last for the entire experimental time explored. Within 24hours post-TBI, a significant elevation in cho-line-derivates, alanine and glucose were also meas-ured. On the other hand, N-acetyl aspartate, a neu-ronal marker, and myo-inositol, an important organic osmolyte in the mammalian brain, were not signifi-cantly impacted in the chronic phase of TBI
Mohammad Talebi, Ahamd Ayatollahi, Ali Kermani
Published: 1 January 2011
Journal of Biomedical Science and Engineering, Volume 04, pp 105-109; https://doi.org/10.4236/jbise.2011.42015

Abstract:
Image segmentation is one of the earliest and most important stages of image processing and plays an important role in both qualitative and quantitative analysis of medical ultrasound images but ultrasound images have low level of contrast and are corrupted with strong speckle noise. Due to these effects, segmentation of ultrasound images is very challenging and traditional image segmentation methods may not be leads to satisfactory results. The active contour method has been one of the widely used techniques for image segmentation; however, due to low quality of ultrasound images, it has encountered difficulties. In this paper, we presented a segmental method combined genetic algorithm and active contour with an energy minimization procedure based on genetic algorithms. This method have been proposed to overcome some limits of classical active contours, as con-tour initialization and local minima (speckle noise), and have been successfully applied on medical ultrasound images. Experimental result on medical ultrasound image show that our presented method only can correctly segment the circular tissue’s on ultra-sound images
Zhuang Miao, Xiaomei Lin, Chengcheng Liu
Published: 1 January 2011
Journal of Biomedical Science and Engineering, Volume 04, pp 100-104; https://doi.org/10.4236/jbise.2011.42014

Abstract:
In medical images, exist often a lot of noise, the noise will seriously affect the accuracy of the segmentation results. The traditional standard fuzzy c-means(FCM) algorithm in image segmentation do not taken into account the relationship the adjacent pixels, which leads to the standard fuzzy c-means(FCM) algorithm is very sensitive to noise in the image. Proposed improvedfuzzy c-means(FCM) algorithm, taking both the local and non-local information into the standard fuzzy c-means(FCM) clustering algorithm. The ex-periment results can show that the improved algorithm can achieve better effect than other methods of brain tissue segmentation
Hidetaka Noritomi, Ken Minamisawa, Reo Kamiya,
Published: 1 January 2011
Journal of Biomedical Science and Engineering, Volume 04, pp 94-99; https://doi.org/10.4236/jbise.2011.42013

Abstract:
Thermal stability of lysozyme dissolved in aqueous solutions was examined in the presence of water-miscible aprotic ionic liquids consisting of 1-ethyl-3-methylimidazolium cation and several kinds of anions. Addition of ionic liquids to an aqueous solution containing lysozyme prevented unfolded proteins from aggregating irreversibly at high temperatures. The thermal denaturation curve of lysozyme with ionic liquids was entirely shifted to higher temperature, compared with that without ionic liquids. The remaining activity of lysozyme after the heat treatment was markedly dependent upon the kind and concentration of ionic liquids. The remaining activi-ties of lysozyme with 1.5 M 1-ethyl-3-methylimida-zolium tetrafluoroborate ([emim][BF4]) and 0.1 M 1-ethyl-3-methylimidazolium trifluoromethanesulfonate ([emim][Tf]) exhibited 88 and 68% after the heat treatment at 90oC for 30 min, respectively, although that without ionic liquids was perfectly lost
Yukinori Eguchi
Published: 1 January 2011
Journal of Biomedical Science and Engineering, Volume 04, pp 90-93; https://doi.org/10.4236/jbise.2011.42012

Abstract:
The PHYGUI for the PHYLIP package is a simple and user-friendly piece of software that acts such as a Windows based graphical-user-interface for the PHYLIP phylogenetic data analysis package. PHYLIP is a useful and powerful tool for phylogenetic research that is regretfully operated using a character-user-interface. Therefore, PHYLIP is difficult for beginner level users. The PHYGUI for PHYLIP adds a GUI function, which makes it a more user-friendly and powerful tool. PHYGUI runs on multiple platforms such as MS-Windows and X windows on Mac OS-X and Linux systems and is mainly operated using a mouse. The input data file and the output result data files can be viewed and edited using internal or ex-ternal text editors, which can be accessed via a button on the PHYGUI for PHYLIP
Franz A. Fellner, Klaus Engel, Christoph Kremer
Published: 1 January 2017
Journal of Biomedical Science and Engineering, Volume 10, pp 367-375; https://doi.org/10.4236/jbise.2017.108028

Abstract:
Modern computer techniques have been in use for several years to generate three-dimensional visualizations of human anatomy. Very good 3-D computer models of the human body are now available and used routinely in anatomy instruction. These techniques are subsumed under the heading “virtual anatomy” to distinguish them from the conventional study of anatomy entailing cadavers and anatomy textbooks. Moreover, other imaging procedures (X-ray, angiography, CT and MR) are also used in virtual anatomy instruction. A recently introduced three-dimensional post-processing technique named Cinematic Rendering now makes it possible to use the output of routine CT and MR examinations as the basis for highly photo-realistic 3-D depictions of human anatomy. We have installed Cinematic Rendering (enabled for stereoscopy) in a high-definition 8K 3-D projection space that accommodates an audience of 150. The space’s projection surface measures 16 × 9 meters; images can be projected on both the front wall and the floor. A game controller can be used to operate Cinematic Rendering software so that it can generate interactive real-time depictions of human anatomy on the basis of CT and MR data sets. This prototype installation was implemented without technical problems; in day-to-day, real-world use over a period of 22 months, there were no impairments of service due to software crashes or other technical problems. We are already employing this installation routinely for educational offerings open to the public, courses for students in the health professions, and (continuing) professional education units for medical interns, residents and specialists—in, so to speak, the dissecting theater of the future.
Published: 1 January 2017
Journal of Biomedical Science and Engineering, Volume 10, pp 355-366; https://doi.org/10.4236/jbise.2017.107027

Abstract:
The behavior of the 2006 ten Tusscher-Panfilov model of human ventricular myocytes under the impact of periodic excitation impulses was studied in the BeatBox simulation environment. The cardiomyocyte model has a limited susceptibility to an forced higher frequency excitation rhythm. A high-frequency excitation rhythm can be forced by gradually increasing the frequency of excitation impulses. The mechanism of defibrillation pulse impact consists of presumably prolonging the refractoriness of cardiomyocytes which undermines their susceptibility for a long time to a forced high-frequency rhythm of fibrillation, as a result for which they hinder the propagation of a fibrillation wave. This is the only mechanism of defibrillation that was identified during the simulation. The threshold energy of a depolarizing defibrillation pulse prolonging the refractoriness of the cardio-myocyte varies depending on a delay relative to the excitation impulse (the excitation cycle phase) in a wide range (the maximum value exceeds the minimum by several thousand times). The results show differences in the mechanisms of impact on a cardiomyocyte between an excitation impulse and a monophasic defibrillation pulse.
Christiane Richter, Frederik Kotz, N. Keller, Tobias M. Nargang, Kai Sachsenheimer, Dorothea Helmer,
Published: 1 January 2017
Journal of Biomedical Science and Engineering, Volume 10, pp 205-218; https://doi.org/10.4236/jbise.2017.105016

Abstract:
In most microfluidic applications, pressure-driven Poiseuille flow in a contained cross-section with no-slip boundary conditions is the underlying fluid-mechanical model. Solutions for this problem exist for many known cross-sections. We have recently demonstrated a simple method to solve the relevant Poisson equation using a finite difference scheme in a spreadsheet analysis tool such as Microsoft Excel. The numerical solutions obtained from such a spreadsheet are close-to-exact to the analytical solutions with errors on the order of only a few percent. However, there are numerous applications in microfluidics for which the no-slip boundary condition is not valid. Examples include drag-reducing air-retaining surfaces as well as open-channel flow. For these scenarios few to no analytical models exist. In this paper, we derive an analytical model for mixed boundary conditions (slip/no-slip) in two dimensions in a rectangular channel cross-section. We also demonstrate that the equivalent numerical solution can be derived conveniently by adaption of the spreadsheet. In general, mixed boundary-type flow scenarios are especially difficult to solve analytically whereas numerical solutions can be derived using Microsoft Excel within seconds.
Svetlana Stepanovna Moisa
Published: 1 January 2017
Journal of Biomedical Science and Engineering, Volume 10, pp 343-354; https://doi.org/10.4236/jbise.2017.107026

Abstract:
The review contains contemporary literature data about calcitonin role in the development of insulin resistance and its potential role in the pathogenesis of carbohydrate metabolism disturbances. Analogues disturbances revealed under diabetes mellitus and under calcitonin treatment are considered. Literature data about hormone diabetogenicity are discussed. The analysis of experimental and literature data testifies that calcitonin under unfavorable conditions (age, obesity, stress) against the background of the decreasing of functional activity of insular apparatus can lead to the development of metabolic syndrome and diabetes mellitus. It is shown that calcium channel blockers inhibit calcitonin effect leads to glucose intolerance and decreases tissue insulin sensitivity. In this connection a question about direct influence on calcium mechanisms of endocrine system as possible method of drug therapy is discussed.
, Sophia Manueldas, Svante Norgren, , , Lars O. Baumbusch
Published: 1 January 2017
Journal of Biomedical Science and Engineering, Volume 10, pp 31-36; https://doi.org/10.4236/jbise.2017.102004

Abstract:
Introduction: Oxidative stress may have detrimental effects on different structures of the cells, such as the DNA. Recently, we have published a study demonstrating that N-Acetylcysteine amide (NACA) displayed anti-inflammatory properties on the brain after exposure to oxidative stress in an established neonatal piglet model, imitating perinatal asphyxia. As different clinical studies have shown an association between the severity of hypoxic-ischemic encephalopathy and damage of the kidneys, we investigated a possible protective effect of NACA against H2O2-induced oxidative stress using a porcine epithelial-like embryonic kidney cell line (EFN-R). Objective: To investigate a potential protective effect of NACA on cells of a porcine embryonic kidney cell line exposed to H2O2. Methods: We subjected the cells to different concentrations of H2O2 for variable time periods, seeking the optimal dose-response for the experiments. Based on the results of these investigations, we exposed the cells to 100 μMol of H2O2 and/or 750 μM of NACA for 24 hours. Some of the cells would receive NACA either one hour before or one hour after exposure to H2O2. Results: The viability of the investigated EFN-R cells revealed that both, the group treated with NACA before exposure to H2O2 and the group treated with NACA after exposure to H2O2, exhibited significantly higher cell viability compared to the H2O2 group (p < 0.001 and p < 0.01, respectively). Discussion: The increased viability of the cells may indicate that NACA could play an important role in reducing oxidative stress. Taking the results from our previous study into consideration, our findings may strengthen the theory that NACA may have organ protective properties for neonates exposed to oxidative stress.
P. Lindholm, Å. Larsson, O. Frånberg, L. Gullstrand
Published: 1 January 2017
Journal of Biomedical Science and Engineering, Volume 10, pp 304-316; https://doi.org/10.4236/jbise.2017.105023

Abstract:
Introduction: Oxygen supplementation increases physical performance during strenuous work, as known for more than 100 years. There is no widespread use among athletes, which could be due to logistical challenges with gas supply when breathing over 200 L/min. We hypothesized that a positive effect could be reached with a moderate increase in alveolar PO2. If so, a technical solution here called “Oxelerator” could be constructed combining intermittent gas supply with oxygen concentrators running of electricity and a small bottle. Methods. This study describes the theoretical details regarding gas flow and consumption as well as a practical test of the Oxelerator when used during intense exercise by two athletes with high VO2 and work capacity. Results: The Oxelerator generates a peak gas flow of 32 L/min dosed intermittently in 400 - 700 ms boluses adjusted to the inspiratory phase of breathing, mixing oxygen with surrounding air. Theoretical calculations show that 1 liter tank suffice for 20 - 40 minutes of high intensity exercise and hyperoxic FEO2 while breathing above 200 L/min. The first subject ran on a treadmill at a VO2 of 4.64 L/min, RER 0.94. Then intermittent oxygen supplementation was initiated, and FEO2 reached 25.96% after 1 minute. The second subject rowed an ergometer at 330 W. VO2 stabilized at 5.67 L/min, with RER 0.91. After 1 minute of oxygen supplementation mixed expired FEO2 was 22.58% suggesting that inspired FO2 averaged 28 - 31%. Conclusions: A portable technical solution is proposed that enable intermittent O2 supplementation enough to increase end-expiratory FO2 during intense workloads. This will enable hyperoxic exercise for athletes.
Anil Lonappan
Published: 1 January 2012
Journal of Biomedical Science and Engineering, Volume 05, pp 476-479; https://doi.org/10.4236/jbise.2012.58060

Abstract:
H1N1 virus is a subtype of influenza A virus and was the most common cause of human influenza flu in 2009. This paper presents a new method of detecting H1N1. The dielectric properties respiratory mucus is studied at microwave frequencies using rectangular cavity perturbation technique at the S-band with the different samples of respiratory mucus obtained from healthy donors as well as from patients suffering from H1N1. It is observed that an appreciably variation is found in the dielectric properties of patient samples as that of normal healthy samples and this measurements were in good agreement with the clinical analysis. This measurement technique is quick, simple and suggests a new novel method of diagnosing H1N1 using microwaves
, Veena Puri, Sanjeev Puri
Published: 1 January 2012
Journal of Biomedical Science and Engineering, Volume 05, pp 469-475; https://doi.org/10.4236/jbise.2012.58059

Abstract:
Hepatocellular Carcinoma is a primary malignant tumor of the liver and gankyrin is an oncoprotein over-expressed in hepatocellular carcinoma. It has been found that Gankyrin protein reduces the level of p53 protein by increasing its ubiquitylation and degradation, following a MDM-2 mediated pathway. Interaction of gankyrin with MDM2 enhances the ubiquitylation of p53. Independent study of this protein molecule revealed that it is identical to the p28 subunit of the 26S proteasome, having seven similar alpha helical ankyrin repeats. Gankyrin also binds to the Tumor Suppressor Protein (TSP) Retinoblastoma (RB), thereby accelerating its phosphorylation and proteasomal degradation. Blocking the expression of Gankyrin with MDM2 in cases of Hepatocellular Carcinoma (HCC) promoted apoptosis in cancer cells. Hence, Gankyrin can be used as a potential target for drug therapy against Hepatocellular Carcinoma
Aurélie Robert, , , Xiu Tian Yan, Francois Peyraut,
Published: 1 January 2012
Journal of Biomedical Science and Engineering, Volume 05, pp 457-468; https://doi.org/10.4236/jbise.2012.58058

Abstract:
In order to help companies to improve their competetiveness, it is important to develop new design methodologies. In this framework, a Functional And Robust Design (FARD) methodology dedicated to routine design of “highly productive” modular product ranges is proposed including principles of functional analysis, Design For Assembly (DFA), and techniques of modelling and simulation for ergonomics consideration. This paper focuses on the application of this original method applied to mechanical vibration and ergonomics problems of a scraper. Including biomechanical aspect in the design methodology, it is possible to identify the impact of a vibration tool on its users using numerical models of the tool coupled to a finite element model of the human hand. This method can proactively warn very early, in the design process, the risks of causing musculoskeletal disorders and facilitate an optimization of the mechanical tool. This study is a first step in a context of human-centered design
Published: 1 January 2012
Journal of Biomedical Science and Engineering, Volume 05, pp 448-456; https://doi.org/10.4236/jbise.2012.58057

Abstract:
Calcium phosphate cements have received much attention in recent decades owing to their biocompatibility, in situ handling, and shaping abilities. However, their low initial mechanical strength is still a major limitation. On the other hand, calcium aluminate cements (CACs) set fast and have a high initial strength and good corrosion resistance in contact with body fluids, making them excellent dental restorative materials. Therefore, the chemical, mechanical and biological properties of new-TCP/CA cement after aging in simulated body fluid (SBF) were investigated. The results indicated that the composites have setting times not appropriated for immediate applications and have degradation rates higher than those of the traditional CPCs. Moreover, the compressive strength of composite was lower than 5MPa and did not increase with SBF immersion. However, the α-TCP/CA composites showed a higher bioactivity at early stages and were not only more biocompatible but also more noncytotoxic
Qi-Hui Luo, Wen Zeng, , , , Yu-Bo Shen, Chun-Mei Zhu, Feng-Jun Bi
Published: 1 January 2012
Journal of Biomedical Science and Engineering, Volume 05, pp 439-447; https://doi.org/10.4236/jbise.2012.58056

Abstract:
Aim Activation of peroxisome proliferator-activated receptor δ (PPARδ) subtypes increases expression of genes involved in fatty acid transport and oxidation and alters adiposity in animal models of obesity and type-2 diabetes. We aim to explore the effects of peroxisome proliferator-activated receptor δ (PPARδ) subtypes on serum lipid profiles in obese rhesus monkey, especially evaluate the efficacy of investigational new drug (HS00098). Methods: First, a prototype of obese rhesus monkey was established by continuously feeding test animals a high fat diet for 2 months. Fifteen obese rhesus monkeys were randomly divided into 3 groups, and the 2 test groups were treated with GW 501516 and HS00098. The test groups were administered doses of 0.3 mg/kg for 1 month, then with 1 mg/kg for 1 month, and finally with 3 mg/kg for 1 month. The control group received placebo treatment. In each experiment, the body weight of each animal was measured and recorded initially and prior to changing the dose of the drug each month. The total cholesterol, blood glucose, triglyceride, high density lipoprotein cholesterol, low-density lipoprotein cholesterol, serum Apo-A1, Apo-B100 and insulin were tested. Results: The average body weight gain of the GW501516 and HS00098 groups was significantly lower than that of the control group. The group receiving the HS00098 treatment had a higher signifycant increase in high density lipoprotein and apo-A1 (P < 0.05) than the control monkeys, while the total cholesterol, triglycerides, low density lipoproteins, apo-B100, and insulin (P < 0.05 or P < 0.01) were significantly decreased. Compared with GW50-1516, the effects of HS00098 on serum lipid profiles in diet-induced obese rhesus monkeys are more obvious. Conclusion: These results suggested that the investigational drug (HS00098) can effectively reduce body weight, blood lipid and blood sugar levels of diet-induced obese rhesus monkeys
Daniel Åkerberg, Carl Grunditz, Monika Posaric-Bauden, Karolin Isaksson, , Bobby Tingstedt
Published: 1 January 2012
Journal of Biomedical Science and Engineering, Volume 05, pp 432-438; https://doi.org/10.4236/jbise.2012.58055

Abstract:
, Siu-Kai Lai, Kar-Ming Leung, Gilberto Ka-Kit Leung, Kwok-Wing Chow
Published: 1 January 2012
Journal of Biomedical Science and Engineering, Volume 05, pp 422-431; https://doi.org/10.4236/jbise.2012.58054

Published: 1 January 2012
Journal of Biomedical Science and Engineering, Volume 05, pp 416-421; https://doi.org/10.4236/jbise.2012.58053

Abstract:
This paper proposes a novel approach for the automatic detection of allergy test (allergy lesion). A hyperspectral microscope system was used to image the test samples which were diagnosed by dermatologist. It was found that allergy of different levels, and healthy skin cells show absorption spectra, which are sufficiently characteristic and yet reproducible enough to allow for differentiation when using a spectroscopic system. Principal components analysis was used to extract relevant features that could be used for classification from these spectra. Preliminary results indicate that the different types of allergy cells can be reliably distinguished by these features. We conclude that hyperspectral microscopic analysis is a promising approach for improving and automating the diagnosis of allergy test as well as another skin lesions
Published: 1 January 2012
Journal of Biomedical Science and Engineering, Volume 05, pp 409-415; https://doi.org/10.4236/jbise.2012.58052

Abstract:
Cone-beam CT (CBCT) scanners are based on volumetric tomography, using a 2D extended digital array providing an area detector [1,2]. Compared to traditional CT, CBCT has many advantages, such as less X-ray beam limitation, and rapid scan time, etc. However, in CBCT images the x-ray beam has lower mean kilovolt (peak) energy, so the metal artifact is more pronounced on. The position of the shadowed region in other views can be tracked by projecting the 3D coordinates of the object. Automatic image segmentation was used to replace the pixels inside the metal object with the boundary pixels. The modified projection data, using synthetically Radon Transformation, were then used to reconstruct a new back projected CBCT image. In this paper, we present a method, based on the morphological, area and pixel operators, which we applied on the Radon transformed image, to reduce the metal artifacts in CBCT, then we built the Radon back project images using the radon invers transformation. The artifacts effects on the 3d-reconstruction is that, the soft tissues appears as bones or teeth. For the preprocessing of the CBCT images, two methods are used to recognize the noisy black areas that the first depends on thresholding and closing algorithm, and the second depends on tracing boundaries after using thresholding algorithm too. The intensity of these areas is the lowest in the image than other tissues, so we profit this property to detect the edges of these areas. These two methods are applied on phantom and patient image data. It deals with reconstructed CBCT dicom images and can effectively reduce such metal artifacts. Due to the data of the constructed images are corrupted by these metal artifacts, qualitative and quantitative analysis of CBCT images is very essential
, Philipp Plank, Bernhard Stadlbauer, Karina Statthaler, John Bosco Uroko
Published: 1 January 2017
Journal of Biomedical Science and Engineering, Volume 10, pp 317-325; https://doi.org/10.4236/jbise.2017.106024

Abstract:
Patients who suffer from a high spinal cord injury have severe motor disabilities in the lower as well as in the upper extremities. Thus they rely on the help of other people in everyday life. Restoring the function of the upper limbs, especially the grasp function can help them to gain some independence. Using EEG-based neuroprosthetics is a way to help tetraplegic people restore different grasp types as well as moving the arm and the elbow. In this work an overview of non-invasive EEG-based methods for restoring the hand and arm function with the use of neuroprosthetics in individuals with high spinal cord injury is given. Since the Graz BCI group is leading in this area of non-invasive research mainly, the work of this group is represented.
E. Bou Assi, S. Rihana, M. Sawan
Published: 1 January 2017
Journal of Biomedical Science and Engineering, Volume 10, pp 326-341; https://doi.org/10.4236/jbise.2017.106025

Abstract:
A right-hand motor imagery based brain-computer interface is proposed in this work. Such a system requires the identification of different brain states and their classification. Brain signals recorded by electroencephalography are naturally contaminated by various noises and interferences. Ocular artifact removal is performed by implementing an auto-matic method “Kmeans-ICA” which does not require a reference channel. This method starts by decomposing EEG signals into Independent Components; artefactual ones are then identified using Kmeans clustering, a non-supervised machine learning technique. After signal preprocessing, a Brain computer interface system is implemented; physiologically interpretable features extracting the wavelet-coherence, the wavelet-phase locking value and band power are computed and introduced into a statistical test to check for a significant difference between relaxed and motor imagery states. Features which pass the test are conserved and used for classification. Leave One Out Cross Validation is performed to evaluate the performance of the classifier. Two types of classifiers are compared: a Linear Discriminant Analysis and a Support Vector Machine. Using a Linear Discriminant Analysis, classification accuracy improved from 66% to 88.10% after ocular artifacts removal using Kmeans-ICA. The proposed methodology outperformed state of art feature extraction methods, namely, the mu rhythm band power.
Hui Hui Xia$Department of Engineering Electromagnetics, , Xin China╃Xin Huang$University of Chinese Academy of Sciences, Minhua Lu, Applications Institute of Electrical Engineering, Chinese Academy of Sciences, Beijing, China╃Minhua Lu\$Guangdong Key Laboratory For Biomedical Measurements And Ultrasound Imaging, Shenzhen, China
Published: 1 January 2017
Journal of Biomedical Science and Engineering, Volume 10, pp 97-105; https://doi.org/10.4236/jbise.2017.105B011

Abstract:
The Magneto-acoustic Tomography with Current Injection (MAT-CI) is a new biological electrical impedance imaging technique that combines Electrical Impedance Tomography (EIT) with Ultrasonic Imaging (UI), which possesses the non-invasive and high-contrast of the EIT and the high-resolution of the UI. The MAT-CI is expected to acquire high quality image and embraces a wide application. Its principle is to put the conductive sample in the Static Magnetic Field(SMF) and inject a time-varying current, during which the SMF and the current interact and generate the Lorentz Force that inspire ultrasonic signal received by the ultrasonic transducers positioned around the sample. And then according to related reconstruction algorithm and ultrasonic signal, electrical conductivity image is obtained. In this paper, a forward problem mathematical model of the MAT-CI has been set up to deduce the theoretical equation of the electromagnetic field and solve the sound source distribution by Green’s function. Secondly, a sound field restoration by Wiener filtering and reconstruction of current density by time-rotating method have deduced the Laplace’s equation that caters to the current density to further acquire the electrical conductivity distribution image of the sample through iteration method. In the end, double-loop coils experiments have been conducted to verify its feasibility.
Monzurul Islam, ,
Published: 1 January 2017
Journal of Biomedical Science and Engineering, Volume 10, pp 86-96; https://doi.org/10.4236/jbise.2017.105b010

Jahid Ferdous, Eva Romito, Heather Doviak, Alexandra Moreira, , Francis G. Spinale,
Published: 1 January 2017
Journal of Biomedical Science and Engineering, Volume 10, pp 287-303; https://doi.org/10.4236/jbise.2017.105022

Abstract:
Bioadhesive polymers can serve as surgical sealants with a wide range of potential clinical applications, including augmentation of wound closure and acute induction of hemostasis. Key determinants of sealant efficacy include the strength and duration of tissue-material adhesion, as well as material biocompatibility. Canonical bioadhesive materials, however, are limited by a tradeoff among performance criteria that is largely governed by the efficiency of tissue-material interactions. In general, increasingly bioreactive materials are endowed with greater bioadhesive potential and protracted residence time, but incite more tissue damage and localized inflammation. One emergent strategy to improve sealant clinical performance is application-specific material design, with the goal of leveraging both local soft tissue surface chemistry and environmental factors to promote adhesive tissue-material interactions. We hypothesize that copolymer systems with equivalent bioreactive group densities (isoreactive) but different amounts/oxidation states of constituent polymers will exhibit differential interactions across soft tissue types. We synthesized an isoreactive family of aldehyde-mediated co-polymers, and subjected these materials to physical (gelation time), mechanical (bulk modulus and adhesion strength), and biological (in-vitro cytotoxicity and in-vivo biocompatibility) assays indicative of sealant performance. Results show that while bioadhesion to a range of soft tissue surfaces (porcine aortic adventitia, renal artery adventitia, renal cortex, and pericardium) varies with isoreactive manipulation, general indicators of material biocompatibility remain constant. Together these findings suggest that isore-active tuning of polymeric systems is a promising strategy to circumvent current challenges in surgical sealant applications.
Sung Jang Chung
Published: 1 January 2017
Journal of Biomedical Science and Engineering, Volume 10, pp 273-286; https://doi.org/10.4236/jbise.2017.105021

Abstract:
A clear and exact quantitative relationship between dose of total body irradiation and mortality in humans is still not known because of lack of human data that would enable us to determine LD50 for humans in total body irradiation. Analysis of human data has been primarily from radiation accidents, radiotherapy and the atomic bomb victims. The author published the general mathematical equations of LD50 constructed on the basis of data presented by Cerveny, MacVittie and Young, employing the probacent formula model. In this study, the author compared the equations of tolerance of total body irradiation and decay of isotopes, uranium and thorium. Differences and similarity in these equations of the two groups are presented. The significance of similarity is specially described.
Lawrence K. F. Wong, Zhiwei Luo, Nobuyuki Kurusu
Published: 1 January 2017
Journal of Biomedical Science and Engineering, Volume 10, pp 243-256; https://doi.org/10.4236/jbise.2017.105019

Abstract:
This study describes the development of a cervical traction therapy simulation model that evaluates two types of the traction positions, namely the sitting position and the inclined position. An anatomically correct human skeleton model and two mechanical traction device models were constructed in simulations using a physics engine. The anterior and posterior intervertebral separations were measured at both positions with a series of traction forces (60N to 200N) and traction angles (10° to 40° ). The result suggested that the sitting position caused the subject to lean forward and as a result led to excessive anterior compression when traction angle is over 20 degrees. The inclined position creates greater intervertebral separations on both the anterior and posterior sides than the sitting position. This suggests that the inclined position may be more effective in increasing intervertebral separation than the sitting position.
Fabiano Ribeiro Cirano, , Márcia Martins Marques, Francisco Emílio Pustiglioni, Luiz Antônio Pugliesi Alves Lima
Published: 1 January 2015
Journal of Biomedical Science and Engineering, Volume 08, pp 380-388; https://doi.org/10.4236/jbise.2015.86036

Published: 1 January 2015
Journal of Biomedical Science and Engineering, Volume 08, pp 389-398; https://doi.org/10.4236/jbise.2015.86037

Abstract:
Because of the three-dimensional structure of bone or hard tissue such as a tooth, a scaffold is necessary for its regeneration by cellular engineering. Commonly, for in vivo examination, hydroxyapatite (HA) has been used as such a scaffold. Cylindrical HA with a hollow center, which included a columnar formalin-treated polyvinyl alcohol sponge, was used in this examination as a scaffold. The sponge had been coated with L-tryptophan or L-lysine before insertion into the hollow center of the HA. Rat bone marrow cells (rBMCs) derived from the femur were seeded in the sponge before insertion into the hollow center of HA. The number of rBMCs seeded in each sponge was 1.5 × 106. These scaffolds were implanted subcutaneously into the backs of Fischer 344 rats for 6 weeks. In the amino-acid-coated sponge in HA, osteogenesis was found histologically. An osteocalcin level of approximately 10 ug was measured in the scaffolds with L-tryptophan-coated formalized poly-vinyl alcohol sponge containing rBMCs, 4 ug on average in the scaffolds with L-lysine-coated sponge containing the cells and about 2 ug in each scaffold with uncoated sponge containing the cells. The structure of the scaffolds used in this study was thought to be suitable for osteogenesis by rBMCs. It was concluded that tryptophan, as a factor for bone formation by stem cells, functioned by promoting cell adhesion and the differentiation of stem cells into osteoblasts.
Wajid Ali, Kanwal Saba, Nasir Raza Zaidi, Tayyaba Majeed,
Published: 1 January 2013
Journal of Biomedical Science and Engineering, Volume 06, pp 609-614; https://doi.org/10.4236/jbise.2013.66077

Abstract:
Hepatocellular carcinoma (HCC) is the fifth most common cancer in the world and the third most common cause of cancer mortality. Despite the high numbers of patients diagnosed worldwide, HCC continues to pose challenging clinical problems. Good-quality ultra sound with careful evaluation of the entire liver can be a screening examination for HCC in patients at risk. The aim of the study was to determine the diagnostic accuracy of the Doppler sonography for differentiation of hepatocellular carcinoma (HCC) from other focal liver lesions by taking histopathology as a gold standard. It was a cross-sectional survey, conducted in the Department of Diagnostic Radiology, King Edward Medical University/Mayo Hospital, Lahore in one year from 13-12-2010 to 12-12-2011. A total of 70 patients were included in this study with focal lesions on ultrasound are included while pregnant patients are excluded. After evaluating by Doppler sonography and doing core biopsy, the patients were sent to the Department of Pathology, Mayo Hospital for histopathological examination. Histopathology was assessed for confirmation of positive and negative cases. Mean age of the patients was 60.9 ± 4.7 years. Out of 70 patients, 47 patients (67.1%) were male while remaining 23 patients (32.9%) were female. On Doppler sonography 37 cases were positive for hepatocellular carcinoma and 33 cases were negative while 36 cases were positive and 34 negative on histopathology. On Doppler sonography, sensitivity (94.4%), specificity (91.1%), diagnostic accuracy (92.8%), positive predictive value (91.8%) and negative predictive value was 93.9%. We concluded that Doppler sonography is a useful method for differen- tiation of Hepatocellular carcinoma from other focal liver lesions, detection and characterization of hepatocellular carcinoma.
Naofumi Shiomi, Keiko Watanabe
Published: 1 January 2013
Journal of Biomedical Science and Engineering, Volume 06, pp 654-660; https://doi.org/10.4236/jbise.2013.66080

Abstract:
Obese individuals exhibit much higher risks not only for metabolic syndrome, but also for cancer and allergies, than normal-weight subjects. This fact suggests that signals secreted from adipocytes change the characteristics of lymphocytes, such as macrophages and T-cells. We focused on a free fatty acid, oleic acid, as a signal inducing such changes and examined its effects on murine J774.2 macrophages. When the cells were cultured in medium containing high concentrations (1, 2 and 4 mM) of oleic acid, apoptosis occurred, and the apoptotic cells were gathered into clusters of very large size by the work of enzymes for phagocytosis. When the cells were cultured in medium containing 0.5 mM of oleic acid, the fatty acid did not affect cell growth; however, it inhibited nitrogen monoxide (NO) secretion and the gene expressions of interleukins and TNF-α. NO disturbs the invasion of macrophages into blood vessels, and interleukins promote the differentiation and proliferation of T- and B-cells. Therefore, these results suggest that the high risks for cancer and allergies observed in obese subjects are associated with the dysfunction of macrophages induced by fatty acids. Moreover, we also examined the protective effects of carnitine against dysfunction. However, carnitine did not exhibit sufficient effects.
Shengjie Yan, Yu Zhou, Bowen Yan, Dianli Li, , Zhaohua Chang
Published: 1 January 2013
Journal of Biomedical Science and Engineering, Volume 06, pp 661-668; https://doi.org/10.4236/jbise.2013.66081

Abstract:
An accurate detection of the effective values of electric voltage and current from high frequency power generators is a precondition for the development of smart electrotomes. In this light, an energy detection system based on personal computer (PC) is developed hereby. It senses voltage and current in isolation from generators with transformers, and then the measured values are amplified, filtered, transformed into single-ended signals and converted to RMS. The detected signals are transformed into digital signals through Data Acquisition Card (DAQ) and the data are processed with quadratic fit in Labview. Finally, the controller completes constant power output. The experiment results indicate that the energy detection system can measure the output parameters precisely and the controller can achieve constant power control.
, , María T. Ronco, Cristina E. Carnovale
Published: 1 January 2013
Journal of Biomedical Science and Engineering, Volume 06, pp 645-653; https://doi.org/10.4236/jbise.2013.66079

Abstract:
Diabetes mellitus (DM) is a serious and growing worldwide health problem and is associated with se- vere acute and chronic complications that negatively influence both quality of life and survival of affected individuals. It is a heterogeneous deregulation of car- bohydrate metabolism. The liver is a central regulator of carbohydrate homeostasis and releases glucose according to metabolic demands. In the last years, the liver injury has been recognized as a major complica- tion of DM. In fact, evidence suggests that in diabetic patients, the mortality rate due to liver cirrhosis is even higher than that due to cardiovascular disease and it has been suggested that there is a two-fold in- creased risk of liver disease in diabetic patients. Among the different types of diabetes, we analyze type 1 dia- betes mellitus as a chronic disorder and an inflam- matory process, which is also associated with in- creased risk of chronic liver injury. Animal models have contributed extensively to the study of diabetes, and it is well established that administration of a unique dose of streptozotocin (STZ) induces insulin- dependent type 1 diabetes mellitus. We analyzed the contribution of Tumor Necrosis Factor alpha (TNF-α) intracellular pathway and oxidative stress in the de- velopment of apoptosis in the liver of streptozotocin- induced diabetic animals. In this review, we describe the role of upstream mediators of the interaction be- tween TNF-α and its receptor, TNF-R1, by assessing the ability of the in vivo treatment with etanercept (TNF-α blocking antibody) to protect against TNF-α- induced apoptosis. Also, we studied the role of iNOS- induction in the TNF-α-induced liver apoptosis by type 1 diabetes, by treatment of diabetic rats with aminoguanidine (selective iNOS inhibitor), which blocked the induction of apoptosis. Interestingly, iNOS inhibition significantly reduced TNF-α levels, evidencing an interaction between TNF-α and iNOS activity. On the other hand, we found that the ad- ministration of antioxidants/hydroxyl radical scaven- gers (Tempol and Desferal) prevented oxidative stress by reducing the effects of hydroxyl radical production and both lipid peroxidation (LPO) levels and apop- tosis. Taken together, our studies support that, at least in part, the hydroxyl radical acts as a reactive inter- mediate, which leads to liver apoptosis in a model of STZ-mediated hyperglycemia. Conclusion and Future: The relevance of the present review is to provide fur- ther knowledge about the mechanisms which may contribute to the disease process in the liver during the course of an inflammatory process as it is type 1 diabetes. Regulation of hepatic TNF-α levels and oxi- dative stress in the diabetic state could be of thera- peutic relevance for the improvement or delay of the hepatic complications linked to chronic hyperglycemia.Fil: Frances, Daniel Eleazar Antonio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Rosario. Instituto de Fisiología Experimental (i); ArgentinaFil: Ingaramo, Paola Inés. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Rosario. Instituto de Fisiología Experimental (i); ArgentinaFil: Ronco, Maria Teresa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Rosario. Instituto de Fisiología Experimental (i); ArgentinaFil: Carnovale, Cristina Ester. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Rosario. Instituto de Fisiología Experimental (i); Argentin
Huseyin Ozdemir, Osman Mermi, M. Gurkan Gurok, Sema Saglam, Hanefi Yildirim, Semih Sec, Specialist Murad Atmaca
Published: 1 January 2013
Journal of Biomedical Science and Engineering, Volume 06, pp 693-697; https://doi.org/10.4236/jbise.2013.66084

Abstract:
Background: Given that on the one side considerable similarities between hypochondriasis and obsessive- compulsive disorder (OCD) by means of sharing a number of features, including intrusive thoughts and repeated checking (Barsky, 1992), on the other side similar structural neuroimaging data that found hypochondriac patients to have significantly smaller mean left and right OFC, and greater left thalamus volumes compared to those of healthy controls. Aims: We considered to investigate the hippocampal neurochemicals, found changed in OCD patients, in hypochondriac patients. Methods: Fifteen patients with hypochondriasis, recruited from our out- or in-patient clinics, were compared with 15 healthy control comparisons in regard to proton magnetic resonance spectroscopy (1H-MRS) imaging of hippocampus. Results: The patients with hypochondriasis had lower right and left NAA/CHO, and NAA/CRE, and near-significant lower right CHO/CRE hippocampal ratios than healthy matched comparison subjects. Conclusion: The data of the present investigation in patients with hypochondriasis provide preliminary evidence of lower right and left NAA/CHO, and NAA/CRE, near-significant lower right CHO/CRE hippocampal ratios, revealing neurochemical alterations in hippocampus and a further support the notion that hypochondriasis shares a variety of neurobiological similarities with OCD.
Luciana Machado, Arnaldo Rodrigues Santos Jr.
Published: 1 January 2013
Journal of Biomedical Science and Engineering, Volume 06, pp 683-692; https://doi.org/10.4236/jbise.2013.66083

Abstract:
Stem cells are seen as a possible solution for organ and tissue regeneration and for the treatment or even cure of various diseases. There are basically two types of stem cells: embryonic and adult stem cells. Embryonic stem cells are derived from embryos and exhibit an extensive multiplication and differentiation potential. On the other hand, adult stem cells, which are found in bone marrow and other tissues, have a lower multiplication and differentiation capacity but are more easily isolated and applied. In adult stem cell therapies using bone marrow or umbilical cord blood transplantation, the differentiation of a certain cell type is induced and its multiplication is stimulated, followed by the implantation of these cells into damaged tissues. Examples of the application of stem cells include the treatment of autoimmune diseases such as type 1 diabetes mellitus and heart diseases. Stem cells open up new prospects for the treatment of a series of diseases. In this respect, basic knowledge of the mechanisms of growth and differentiation of these cells is of the utmost importance to optimize therapeutic results. In this review, we discuss the mechanisms of stem cell differentiation and describe the clinical results reported in the literature, mainly by Brazilian research groups.
Jie Yang, Sen Li, Yan-Xin Liu
Published: 1 January 2013
Journal of Biomedical Science and Engineering, Volume 06, pp 615-644; https://doi.org/10.4236/jbise.2013.66078

Abstract:
Alzheimer disease has been defined as Type 3 Diabetes due to their shared metabolic profiles. Like our previously research, results of Alzheimer’s disease and other neurodegenerative diseases, systematic analysis of diabetes- and glucose metabolism-related proteins also provides help in the treatment of Alzheimer’s patients. Some interesting results indicate that diabetes-related proteins (DRPs) are rich in Lys and the content of Trp can distinguish between type 1 and type 2 diabetes mellitus in particular, while glucose metabolism-related proteins (GMRPs) possess Leurich and Trp-poor character. Moreover, the usage biases of codons depend on GC contents to a great extent, in concord with all codons of the highly expressed genes with the terminal of C/G. Especially, the deficit of CpG dinucleotides is largely attributed to the hypermutability of methylated CpGs to UpGs by the mutational pressure. Besides a common node insulin receptor, there are some similar node proteins, such as glucose transporter member, protein tyrosine phosphatase, and adipose metabolism signal protein. The sharing proteins involve glucagon, amylin, insulin, PPARγ, angiopoietin, PC-1/ENPP1, and adiponectin mediated signal pathway. Meanwhile, the gene sequences of node proteins contained the binding sites of 37 transcription factors divide into four kinds of superclasses. Additionally, BAD complex can integrate pathways of glucose metabolism and apoptosis by BH3 domain of BAD directly interacting with GK as well as GK binding with the consensus motif [G]-[1]-[K]-[2]-[S/T] or [L/M]-[R/K]-[2]-[T] of PP1 or WAVE1. This facilitates the therapies for diabetes mellitus as well as Alzheimer’s disease.
Published: 1 January 2013
Journal of Biomedical Science and Engineering, Volume 06, pp 598-608; https://doi.org/10.4236/jbise.2013.66076

Abstract:
This work presents the dynamical modelling of cardiac electrical activity using bidomain approach. It focuses on the effects of variation of the ionic model parameters on cardiac wave propagation. Cardiac electrical activity is governed by partial differential equations coupled to a system of ordinary differential equations. Numerical simulation of these equations is computationally expensive due to their non-linearity and stiffness. Nevertheless, we adopted the bidomain model due to its ability to reflect the actual cardiac wave propagation. The derived bidomain equations coupled with FitzHugh-Nagumo’s ionic equations were time-discretized using explicit forward Euler method and space-discretized using 2-D network modelling to obtain linearized equations for transmembrane potential Vm, extracellular potential φe and gating variable w. We implemented the discretized model and performed simulation experiments to study the effects of variation of ionic model parameters on the propagation of electrical wave across the cardiac tissue. Time characteristic of transmembrane potential, Vm, in the normal cardiac tissue was obtained by setting the values of ionic model parameters to 0.2, 0.2, 0.7 and 0.8 for excitation rate constant ε1, recovery rate constant ε2, recovery decay constant γ and excitation decay constant β respectively. Changing the values of ε1, ε2 to 0.04 and 0.28 respectively, the obtained Vm showed a time dilation at 0.04 indicating cardiac arrhythmia but no significant change to Vm was observed at 0.28. Also, changing β to 0.3 and 1.1 and γ to 0.4 and 1.2 sequentially, there was no significant change to the time characteristic of Vm. The obtained results revealed that only decrease in ε1, ε2 impacted significantly on the cardiac wave propagation.
Muluemebet Ketete, , Abid R. Maqbool, John Kwagyan, Shichen Xu,
Published: 1 January 2013
Journal of Biomedical Science and Engineering, Volume 06, pp 593-597; https://doi.org/10.4236/jbise.2013.66075

Abstract:
Background: Cardiovascular diseases (CVD) are the leading cause of morbidity and mortality in Western societies and are rapidly becoming a worldwide health problem. African-Americans have increased morbidity and mortality rates from CVD. Our study aimed to assess the effects of the CVD risk factors burden alone versus with diabetes mellitus in a high riskCVDpopulation. Methods: The two study groups consisted of thirty seven diabetics and thirty seven non-diabetic African-Americans aged ≥55 years without clinical atherosclerosis having similar cardiovascular risk factors (age, hypertension, hypercholesterolemia, smoking, and body mass index) except for diabetes mellitus. Brachial artery flow-mediated dilation (FMD), Nitroglycerin-mediated dilatation (NMD) and carotid intima-media thickness (IMT) were recorded in all subjects. Results: Endothelial function as assessed by the brachial artery FMD was significantly impaired in the diabetic group compared to the non-diabetic group (7.8 ± 5 vs 3.3 ± 4; p = 0.0001). There were no differences in neither Nitroglycerin-mediated dilatation (NMD) nor carotid intima-media thickness (IMT) in the diabetic and non-diabetic groups. Conclusion: The contribution of diabetes to the development of endothelial dysfunction in subjects with clustering of CVD risk factors may be early as indicated by significant functional changes preceeding structural vascular changes..
, , Toru Sato, Masao Yoshinari
Published: 1 January 2013
Journal of Biomedical Science and Engineering, Volume 06, pp 273-276; https://doi.org/10.4236/jbise.2013.63034

Abstract:
Reza Ramazani-Rend, Srikar Chelikani, , John P. Abraham
Published: 1 January 2010
Journal of Biomedical Science and Engineering, Volume 03, pp 1108-1116; https://doi.org/10.4236/jbise.2010.311144

Abstract:
A definitive, quantitative investigation has been performed to determine whether orbital atherectomy gives rise to cavitation. The investigation encompassed a synergistic interaction between in vitro experimentation and numerical simulation. The experimentation was performed in two independent fluid environments: 1) a transparent tube having a diameter similar to that of the superficial femoral artery and 2) a large, fluid-filled, open-topped container. All of the experimental and simulation work was based on the geometric model of the Diamondback 360 atherectomy device (Cardiovascular Systems, Inc., St. Paul, MN). Rotational speeds ranged from 80,000 to 214,000 rpm. The presence or absence of cavitation in the experiments was assessed by means of high-speed photography. The photographic images clearly display the fact that there was no cavitation. Flow visualization revealed the presence of fluid flows driven by pressure gradients created by the geometry of the rotating crown. The numerical simulations encompassed the fluid environments and the operating conditions of the experiments. The key result of the numerical simulation is that the minimum fluid pressure due to the rotational motion was approximately 50 times greater than the saturation vapor pressure of the fluid. Since the onset of cavitation requires that the fluid pressure falls below the saturation vapor pressure, the computational outcome strongly supports the experimental findings
, Keishi Iohara, Tetsuo Kato, , Masao Yoshinari
Published: 1 January 2010
Journal of Biomedical Science and Engineering, Volume 03, pp 1069-1072; https://doi.org/10.4236/jbise.2010.311138

Abstract:
Protamine was investigated for its antibacterial activity against the periodontal pathogens, Porphyromonas gingivalis, Prevotella intermedia and Aggregatibacter actinomycetemcomitans. We determined the minimum inhibitory concentrations of protamine and its hydrolysate and their bactericidal activity. Protamine inhibited the growth of all periodontopathic bacteria tested on agar plates. Protamine, which MIC was 6.3 × 10-7 g L-1, was most effective against P. gingivalis. The antibacterial effect of native protamine was higher than that of its hydrolysate. An ATP bioluminescence assay revealed that protamine showed bactericidal activity against P. gingivalis in a time-dependent manner. These results indicate that protamine could be candidate peptide for prevention of P. gingivalis infection.
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