Journal Information
ISSN / EISSN : 20461402 / 20461402
Current Publisher: F1000 Research, Ltd. (10.12688)
Former Publisher: F1000 Research Ltd (10.3410)
Total articles ≅ 5,553
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Lili Anggraini, Yetti Marlida, Wizna Wizna, Jamsari Jamsari, Mirzah Mirzah, Frederick Adzitey, Nurul Huda
Published: 17 October 2019
F1000Research, Volume 7; doi:10.12688/f1000research.16224.3

Abstract:Background: Dadih (fermented buffalo milk) is a traditional Indonesian food originating from West Sumatra province. The fermentation process is carried out by lactic acid bacteria (LAB), which are naturally present in buffalo milk. Lactic acid bacteria have been reported as one of potential producers of γ-aminobutyric acid (GABA). GABA acts as a neurotransmitter inhibitor of the central nervous system. Methods: In this study, molecular identification and phylogenetic analysis of GABA producing LAB isolated from indigenous dadih of West Sumatera were determined. Identification of the GABA-producing LAB DS15 was based on conventional polymerase chain reaction. 16S rRNA gene sequence analysis was used to identify LAB DS15. Results: PCR of the 16S rRNA gene sequence of LAB DS15 gave an approximately 1400 bp amplicon. Phylogenetic analysis showed that LAB DS15 was Pediococcus acidilactici, with high similarity of 99% at 100% query coverage to Pediococcus acidilactici strain DSM 20284. Conclusions: It can be concluded that GABA producing LAB isolated from indigenous dadih was Pediococcus acidilactici.
Published: 17 October 2019
F1000Research; doi:10.12688/f1000research

Silvia Sabry Tawfik, Mohamed Adel Ezzat Khairy, Maha Abd Elsalam Elbaz, Maha Ebrahim Mohamed El Korashy
Published: 16 October 2019
F1000Research, Volume 8; doi:10.12688/f1000research.20841.1

Abstract:Background: Dental bleaching has become one of the most demanded aesthetic procedures as it is very simple and gives fast results that satisfy the patient’s wishes. However, unfortunately, it has the annoying side effect of tooth sensitivity. This clinical trial was designed to evaluate the efficacy of using a desensitizing agent, which was applied during in-office bleaching with 30% HP (hydrogen peroxide). Methods: 36 participants were divided into four groups (N = 9). According to the intended intervention as follows: Group I:—Application of Relief ®Amorphous Calcium Phosphate (ACP) before in-office bleaching; Group II—Application of Relief ®ACP before and after in-office bleaching; Group III—Application of Relief ®ACP after in-office bleaching; and Group IV: placebo was applied before and after in-office bleaching. Then, three hydrogen peroxide bleaching applications for a total of 45 minutes were performed. The primary outcome variable was hypersensitivity, assessed with (VAS) scale immediately and 24h, 1 week and 1 month after the procedure; while the secondary outcome was teeth shade assessed using the VITAPAN ® classical shade guide. Results: Statistical analysis was done using Kolmogorov-Smirnov, Shapiro-Wilk tests, Kruskal-Wallis test and Dunn’s test. Immediately after bleaching, there was statistically significant distinction in the median pain score between the groups. After 1 day, the ACP gel before and after bleaching group showed the lowest median score, while, the control group confirmed the highest median score. After 2 days, no statistically sizable difference was observed between all groups. The group receiving ACP gel before and after showed the highest change in median of classical shade guide scores while, (ACP gel after) and control group; showed the lowest change. Conclusion: The application of the desensitizing agent prior to and after in–office bleaching was successful in lowering post-bleaching hypersensitivity. Trail Registration: Clinical trial.gov NCT02942082 21/10/2016
Pujitha Kudaravalli, Sheikh A. Saleem, Sana Riaz, Bishnu Sapkota
Published: 16 October 2019
F1000Research, Volume 8; doi:10.12688/f1000research.20520.1

Abstract:Introduction: Eosinophilic gastroenteritis (EGE) is an extremely rare inflammatory disorder with an estimated prevalence of 22-28/100 000. We herein, present a case of EGE in an elderly patient which was successfully managed with dietary restriction. Case report: A 70-year-old male with a history of gastroesophageal reflux disorder (GERD), atopic dermatitis and asthma presented with 2 weeks history of foul-smelling non-bloody diarrhea associated with nausea, vomiting and weight loss. Physical examination was significant for dry oral mucosa and loss of skin turgor. Lab findings were significant for a hemoglobin of 13.2 g/dl, hematocrit of 38.5%, mean corpuscular volume of 86.3%, white blood cell count of 24,200/mm3, albumin of 2.2 g/L, stool fat of 70g, stool osmolar gap of 115, C-reactive protein 1.47. Erythrocyte sedimentation rate, HIV test were unremarkable. Infectious stool work-up was negative. Computed tomography of the abdomen was unremarkable. The mucosa appeared mildly inflamed on upper endoscopy and colonoscopy, and biopsies showed eosinophilic infiltration of the mucosal and muscular layers. A diagnosis of eosinophilic gastroenteritis was made after other causes such as parasitic infection, drug use and malignancy were ruled out. The patient was counseled on a six-food elimination diet which successfully resolved his diarrhea. The patient did not have any relapses with dietary modification on follow-up. Discussion: The recurrence rate of EGE is 50%. Steroids improve symptoms in 90% of cases but the recurrence rates are high. The type, dose and duration of steroid therapy is unclear. Sodium cromoglicate, ketotifen, and Montelukast are other proposed treatments, the results being inconclusive. Bowel resection is performed in intestinal obstruction, but medical therapy is needed as recurrence in other segments in common. Dietary modification, a therapy with no side-effects should be the first line of treatment as it can result in resolution sparing the patient of steroid induced side effects.
Rodolphe Pelissier, Mathieu Iampietro, Branka Horvat
Published: 16 October 2019
F1000Research, Volume 8; doi:10.12688/f1000research.19975.1

Abstract:Nipah virus (NiV) is a highly lethal zoonotic paramyxovirus that emerged at the end of last century as a human pathogen capable of causing severe acute respiratory infection and encephalitis. Although NiV provokes serious diseases in numerous mammalian species, the infection seems to be asymptomatic in NiV natural hosts, the fruit bats, which provide a continuous virus source for further outbreaks. Consecutive human-to-human transmission has been frequently observed during outbreaks in Bangladesh and India. NiV was shown to interfere with the innate immune response and interferon type I signaling, restraining the anti-viral response and permitting viral spread. Studies of adaptive immunity in infected patients and animal models have suggested an unbalanced immune response during NiV infection. Here, we summarize some of the recent studies of NiV pathogenesis and NiV-induced modulation of both innate and adaptive immune responses, as well as the development of novel prophylactic and therapeutic approaches, necessary to control this highly lethal emerging infection.
Faith A. Kwa, Nabeela K. Dulull, Ute Roessner, Daniel A. Dias, Thusitha W. Rupasinghe
Published: 16 October 2019
F1000Research, Volume 8; doi:10.12688/f1000research.19598.2

Abstract:Background: Age-related macular degeneration (AMD) is a leading cause of blindness in the ageing population. Without effective treatment strategies that can prevent disease progression, there is an urgent need for novel therapeutic interventions to reduce the burden of vision loss and improve patients’ quality of life. Dysfunctional innate immune responses to oxidative stress observed in AMD can be caused by the formation of oxidised lipids, whilst polyunsaturated fatty acids have shown to increase the risk of AMD and disease progression in affected individuals. Previously, our laboratory has shown that the vegetable-derived isothiocyanate, L-sulforaphane (LSF), can protect human adult pigment epithelial cells from oxidative damage by upregulating gene expression of the oxidative stress enzyme Glutathione-S-Transferase µ1. This study aims to validate the protective effects of LSF on human retinal cells under oxidative stress conditions and to reveal the key players in fatty acid and lipid metabolism that may facilitate this protection. Methods: The in vitro oxidative stress model of AMD was based on the exposure of an adult retinal pigment epithelium-19 cell line to 200µM hydrogen peroxide. Percentage cell proliferation following LSF treatment was measured using tetrazolium salt-based assays. Untargeted fatty acid profiling was performed by gas chromatography-mass spectrometry. Untargeted lipid profiling was performed by liquid chromatography-mass spectrometry. Results: Under hydrogen peroxide-induced oxidative stress conditions, LSF treatment induced dose-dependent cell proliferation. The key fatty acids that were increased by LSF treatment of the retinal cells include oleic acid and eicosatrienoic acid. LSF treatment also increased levels of the lipid classes phosphatidylcholine, cholesteryl ester and oxo-phytodienoic acid but decreased levels of phosphatidylethanolamine lipids. Conclusions: We propose that retinal cells at risk of oxidative damage and apoptosis can be pre-conditioned with LSF to regulate levels of selected fatty acids and lipids known to be implicated in the pathogenesis and progression of AMD.
Laura McCulloch, Stuart M. Allan, Hedley C. Emsley, Craig J. Smith, Barry W. McColl
Published: 16 October 2019
F1000Research, Volume 8; doi:10.12688/f1000research.19308.2

Abstract:Background: Blockade of the cytokine interleukin-1 (IL-1) with IL-1 receptor antagonist (IL-1Ra) is a candidate treatment for stroke entering phase II/III trials, which acts by inhibiting harmful inflammatory responses. Infection is a common complication after stroke that significantly worsens outcome and is related to stroke-induced deficits in systemic immune function thought to be mediated by the sympathetic nervous system. Therefore, immunomodulatory treatments for stroke, such as IL-1Ra, carry a risk of aggravating stroke-associated infection. Our primary objective was to determine if factors associated with antibody-mediated antibacterial defences were further compromised in patients treated with IL-1Ra after stroke. Methods: We assessed plasma concentrations of immunoglobulin isotypes and complement components in stroke patients treated with IL-1Ra or placebo and untreated non-stroke controls using multiplex protein assays. Activation of the sympathetic nervous system (SNS) was determined by measuring noradrenaline, a major SNS mediator. Results: There were significantly lower plasma concentrations of IgM, IgA, IgG1 and IgG4 in stroke-patients compared to non-stroke controls, however there were no differences between stroke patients treated with placebo or IL-1Ra. Concentrations of complement components associated with the classical pathway were increased and those associated with the alternative pathways decreased in stroke patients, neither being affected by treatment with IL-1Ra. Noradrenaline concentrations were increased after stroke in both placebo and IL-1Ra-treated stroke patients compared to non-stroke controls. Conclusion: These data show treatment with IL-1Ra after stroke does not alter circulating immunoglobulin and complement concentrations and is therefore unlikely to further aggravate stroke-associated infection susceptibility through altered availability of these key anti-microbial mediators.
Douglas G. Manuel, Carol Bennett, Richard Perez, Andrew S. Wilton, Adrian Rohit Dass, Audrey Laporte, David A. Henry
Published: 16 October 2019
F1000Research, Volume 8; doi:10.12688/f1000research.18205.2

Abstract:Background: Smoking, unhealthy alcohol consumption, poor diet and physical inactivity are leading risk factors for morbidity and mortality, and contribute substantially to overall healthcare costs. The availability of health surveys linked to health care provides population-based estimates of direct healthcare costs. We estimated health behaviour and socioeconomic-attribute healthcare costs, and how these have changed during a period when government policies have aimed to reduce their burden. Methods: The Ontario samples of the Canadian Community Health Surveys (conducted in 2003, 2005, and 2007-2008) were linked at the individual level to all records of health care use of publicly funded healthcare. Generalized linear models were estimated with a negative binomial distribution to ascertain the relationship of health behaviours and socioeconomic risk factors on health care costs. The multivariable cost model was applied to unlinked, Ontario CCHS samples for each year from 2004 to 2013 to examine the evolution of health behaviour and socioeconomic-attributable direct health care expenditures over a 10-year period. Results: We included 80,749 respondents, aged 25 years and older, and 312,952 person-years of follow-up. The cost model was applied to 200,324 respondents aged 25 years and older (CCHS 2004 to 2013). During the 10-year period from 2004 to 2013, smoking, unhealthy alcohol consumption, poor diet and physical inactivity attributed to 22% of Ontario’s direct health care costs. Ontarians in the most disadvantaged socioeconomic position contributed to 15% of the province’s direct health care costs. Combined, these health behaviour and socioeconomic risk factors were associated with 34% ($134 billion) of direct health care costs (2004 to 2013). Over this time period, we estimated a 1.9% reduction in health care expenditure ($5.0 billion) attributable to improvements in some health behaviours, most importantly reduced rates of smoking. Conclusions: Adverse health behaviours and socioeconomic position cause a large direct health care system cost burden.
Thiago Bruder-Nascimento, Taylor C. Kress, Eric J. Belin De Chantemele
Published: 16 October 2019
F1000Research, Volume 8; doi:10.12688/f1000research.20150.1

Abstract:Lipodystrophy is a disease characterized by a partial or total absence of adipose tissue leading to severe metabolic derangements including marked insulin resistance, type 2 diabetes, hypertriglyceridemia, and steatohepatitis. Lipodystrophy is also a source of major cardiovascular disorders which, in addition to hepatic failure and infection, contribute to a significant reduction in life expectancy. Metreleptin, the synthetic analog of the adipocyte-derived hormone leptin and current therapy of choice for patients with lipodystrophy, successfully improves metabolic function. However, while leptin has been associated with hypertension, vascular diseases, and inflammation in the context of obesity, it remains unknown whether its daily administration could further impair cardiovascular function in patients with lipodystrophy. The goal of this short review is to describe the cardiovascular phenotype of patients with lipodystrophy, speculate on the etiology of the disorders, and discuss how the use of murine models of lipodystrophy could be beneficial to address the question of the contribution of leptin to lipodystrophy-associated cardiovascular disease.
Afolakemi Simbo Ogunbanwo, Julius Olatunji Okesola, Sheryl Buckley
Published: 16 October 2019
F1000Research, Volume 8; doi:10.12688/f1000research.18223.2

Abstract:Background: Knowledge management (KM) is a recipe for increasing performance and promoting innovation in tertiary institutions. However, some scholars argue that the Nigerian educational sector is yet to fully appreciate the importance of KM as their KM awareness level is still low. Since measurement is the basic foundation to accomplish success, this paper assesses the KM awareness level in tertiary institutions of south-west Nigeria. Methods: The study applied a survey method using a closed ended questionnaire administered to 50 participants from each of the 10 institutions measured by Likert scaling. Employing SPSS for data analysis, frequency count and percentage score were adopted to analyse the demographic data, and the research hypotheses were analysed with chi square test, Pearson chi square and bivariate correlation (Pearson) analysis. Results: A positive relationship between awareness, current status and level of familiarity was noted. KM awareness level in the institutions is high even though there is a significant difference between the public and private universities, as well as between the students and academic staff. Conclusions: Since an increase in the awareness level increases both current status and level of familiarity which often account for KM success, it is recommend that KM awareness level should continuously be improved upon in Nigerian tertiary institutions.