bluuebunny/crossref_metadata_2025_split huggingface dataset:
Intestinal microbiota balance modulates host susceptibility to infection with enteric pathogenss
Authors: Sekirov I , Tam N , Robertson M , Lupp C , Finlay B 
Published: May 2017

Background: During our lifetimes we develop a very complex set of interactions with the multitude of microorganisms colonizing our bodies. In the gastrointestinal system, the microbiota is highly important for morphological development, nutrition, and protection against infectious diseases. The gastrointestinal pathogens, enterohemorrhagic and enteropathogenic Escherichia coli (EHEC and EPEC) and Salmonella enterica serovar Typhimurium (ST) are food-borne pathogens that cause much morbidity and mortality worldwide. Citrobacter rodentium (Cr) is a mouse pathogen that is used in small animal models to mimic EHEC and EPEC infections.
Methods: We began to characterize the contribution of intestinal microbiota to the progression of these infections. Two main phyla comprise the majority of mouse intestinal microbiota: Bacteroidetes and Firmicutes. Bacteria from a number of additional phyla are also present in smaller numbers; among them γ-Proteobacteria class, belonging to Proteobacteria phylum, is note-worthy as this class harbours many intestinal pathogens, such as ST and Cr. The mouse intestinal microbiota was perturbed using tetracycline (Tet) and streptomycin (Sm) to increase the proportion of Bacteroidetes in the colonic microbiota, and using vancomycin (Vanc) to create a predominance of Firmicutes. The mice with this perturbed microbiota were infected with ST to investigate the resultant pathology and virulence characteristics, and any additional shifts in microbiota as a result of infection.
Results: Treatment of mice with Sm and Vanc was found to decrease the resistance of mice to colonization with ST, while Tet-treated mice exhibited unchanged colonization resistance. Treatment of mice with gradually increasing doses of Sm, which gradually augmented the proportion of CFB bacteria in the microbiota, resulted in progressively increasing colonization of mice by ST, as well as a step-wise increase in the ST-induced typhlitis, associated with higher levels of inflammatory markers IL-6 and KC. The increasing levels of ST colonization following both Sm and Vanc treatment were associated with an increase in the proportion of γ-Proteobacteria in the cecal and colonic microbiota, as well as a decrease in the total bacterial numbers in both organs.
Conclusions: It is evident that the intestinal microbiota plays a significant role in the host’s response to infection with enteric pathogens, and its composition and numbers are also affected by the offending bacteria. Elucidation of the details regarding the contribution of the microbiota to infectious disease progression will offer novel targets for the future design of superior prevention and treatment methods.
Prevalence of metabolic syndrome in never treated mood disordered patientss
Authors: Taylor Valerie , MacQueen Glenda M. 
Published: May 2017

Bipolar disorder and major depression are life-shortening illnesses. Unnatural causes such as suicide and accidents account for only a portion of this premature mortality1 Research is beginning to identify that mood disordered patients have a higher incidence of metabolic syndrome, an illness characterized by dyslipidemia, impaired glucose tolerance, hypertension and obesity.2 Metabolic syndrome is associated with an increased risk for a variety of physical illnesses.
Hypothesis: Never treated patients with mood disorders have preexisting elevations in the prevalence of the component variables of metabolic syndrome. Central obesity will be especially elevated, predicting increased premature mortality.
Methods: We assessed never treated patients with mood disorders for metabolic syndrome and its component variables. Patients were assessed at baseline and followed up at 6-month intervals. All psychiatric pharmacotherapy was documented. Body mass index (BMI) was also obtained and the percentage of deaths attributable to overweight and obesity was calculated using the population attributable risk (PAR). [PAR= ∑[P (RR-1)/RR]
Results: Prior to the initiation of treatment, patients did not differ from population norms with respect to metabolic syndrome or BMI. At 2-year follow-up, BMI had increased for unipolar patients 2.02 points and 1.92 points for bipolar patients. (p < .001) This increase in BMI predicted an increase in mortality of 19.4%.
Conclusion: An increase in visceral obesity is often the first component of metabolic syndrome to appear and may indicate the initiation of this disease process prematurely in this group. The increase in BMI places patients with mood disorders at risk for premature mortality and indicates a need for early intervention.
References
1.Osby U, Brandt L, Correia N, Ekbom A & Sparen P. Excess mortability in bipolar and Unipolar disorder rin Sweden. Archives of General Psychiatry, 2001;58: 844-850
2.Toalson P, Saeeduddin A, Hardy T & Kabinoff G. The metabolic syndrome in patients with severe mental illness. Journal of Clinical Psychiatry, 2004; 6(4): 152-158
Mast cells release cytokines in response to mediators produced by virus-infected epithelial cellss
Authors: Tsang Candy , Befus A. D. 
Published: May 2017

Background: Mast cells have long been recognized for their involvement in allergic diseases. In the last decade, the importance of mast cells in innate responses against bacteria has been established, but little is known about their contribution in viral infections. Mast cells are abundant at mucosal surfaces such as the lungs in close proximity to the epithelium. In the lung, the epithelium is a primary target for viral infections. Mast cells are secondarily exposed to newly formed virions released from epithelial cells. Mast cells have toll-like receptors (TLRs) that detect various pathogen components. Our first hypothesis is that viral TLR agonists will induce mast cells to release cytokines thought to be involved in viral infections. Both the pro-inflammatory cytokine IL-6 and the chemokine IL-8 are produced during viral infections. TGF-β is an immunoregulatory cytokine that modulates the activity of various immune cells and could also play a role in viral infections.
Methods: We used polyI:C, a synthetic double-stranded RNA (dsRNA), as a TLR3 agonist, loxoribine as a TLR7 agonist, and unmethylated CpG DNA as a TLR9 agonist. We treated mast cells from the cell line HMC-1 (Human Mast cell-1) for 0.5 – 24hr with the TLR agonists and performed dose response studies for all stimuli. Supernatants from treated mast cells were measured for IL-6, IL-8, and TGF-β by ELISA.
Results: Cytokine release was highest at the 24hr time point. Mast cells released IL-6, IL-8, and TGF-β in response to the TLR3 agonist polyI:C in a dose-dependent manner, but not to the other viral TLR agonists. PolyI:C (10μg/mL) versus unstimulated controls significantly increased mast cell release of IL-6 (224.7±57.4 vs. 39.0±5.7, p≤0.001) and TGF-β (240.2±28.9 vs. 116.1±16.7, p≤0.05). PolyI:C induced release of IL-8 from mast cells was increased but not significant. Viral exposure also induces epithelial cells to produce type I interferons, IFNα and β. These interferons have potent antiviral activity, but also have effects on mast cells, decreasing mast cell adhesion to extracellular matrix and reducing co-stimulatory activity on T cells. Our second hypothesis is that IFNα and β will induce mast cells to release cytokines similar to stimulation with polyI:C. Our preliminary data showed that IFNα, IFNβ , and IFNα and β in combination induced a low level of IL-8 and TGF-β release from mast cells, but had no effect on IL-6 release.
Conclusion: HMC-1 responds to dsRNA, a TLR3 agonist produced in epithelial cells during viral replication, by releasing IL-6 and TGF-β. HMC-1 also responds to IFNα and β by releasing IL-8 and TGF-β, indicating that human mast cells respond to epithelial mediators produced during viral infections. Our results show that mast cells contribute to the innate response against viruses by responding to mediators released by virus-infected epithelial cells.
Gene transfer of endothelial NO-synthase restores migratory capacity of endothelial progenitor cells from patients with coronary artery diseases
Authors: Ward Michael R. , Zhang Qiuwang , Stewart Duncan J. , Kutryk Michael J.B. 
Published: May 2017

Autologous endothelial progenitor cells (EPCs) have been used extensively in the development of cell-based therapy for acute MI. However, EPCs isolated from patients with CAD and/or CAD risk factors have reduced regenerative activity compared to cells from healthy subjects. As in endothelial cells, endothelial NO synthase (eNOS) expression and subsequent NO production are believed to be critical determinants of EPC function. Recently, the ability of EPCs to migrate in vitro in response to chemotactic stimuli has been shown to predict their regenerative capacity in clinical studies. Therefore, we hypothesized that the regenerative function of EPCs from patients with or at high risk for CAD will be enhanced by overexpression of eNOS, as assessed by migratory capacity.
Methods: EPCs were isolated from the blood of human subjects with CAD risk factors (>15% Framingham risk score; FRS) (± CAD) by Ficoll gradient separation and differential culture. Following 3 days in culture, cells were transduced using lentivirus vectors containing either eNOS or GFP (sham) at an MOI of 3. The cells were cultured for an additional 5 days before being used in functional assays. Cell migration and chemotaxis in response to VEGF (50 ng/mL) and SDF-1 (100 ng/mL) were assessed using a modified Boyden Chamber assay.
Results: Transduction at an MOI of 3 led to a ~90-100-fold increase in eNOS mRNA expression and a 5-6 fold increase in eNOS protein expression, as assessed by qRT-PCR and Western Blotting. Moreover, there was a significant improvement in the migration of EPCs following eNOS transduction compared to sham-transduced EPCs in response to both VEGF (44.3 ± 8.4 vs. 31.1 ± 4.6 cells/high power field; n=10, p < 0.05) and SDF-1 (51.9 ± 11.1 vs. 34.5 ± 3.3 cells/HPF; n=10, p < 0.05).
Conclusions: These data show that the reduced migration capacity of EPCs isolated from patients with CAD and/or CAD risk factors can be significantly improved through eNOS overexpression in these cells. Thus, eNOS transduction of autologous EPCs may enhance their ability to restore myocardial perfusion and function following acute MI. We intend to further explore the regenerative potential of eNOS-transduced EPCs using various in vitro and in vivo models.
The warburg effect and tumour cell survival in human GBMs
Authors: Wolf A , Mukherjee J , Guha A 
Published: May 2017

Introduction: GBMs are resistant to apoptosis induced by the hypoxic microenvironment and standard therapies including radiation and chemotherapy. We postulate that the Warburg effect, a preferential glycolytic phenotype of tumor cells even under aerobic conditions, plays a role in these aberrant pro-survival signals. In this study we quantitatively examined the expression profile of hypoxia-related glycolytic genes within pathologically- and MRI-defined “centre” and “periphery” of GBMs. We hypothesize that expression of hypoxia-induced glycolytic genes, particularly hexokinase 2 (HK2), favours cell survival and modulates resistance to tumour cell apoptosis by inhibiting the intrinsic mitochondrial apoptotic pathway.
Methods: GBM patients underwent conventional T1-weighted contrast-enhanced MRI and MR spectroscopy studies on a 3.0T GE scanner, prior to stereotactic sampling (formalin and frozen) from regions which were T1-Gad enhancing (“centre”) and T2-positive, T1-Gad negative (“periphery”). Real-time qRT-PCR was performed to quantify regional gene expression of glycolytic genes including HK2. In vitro functional studies were performed in U87 and U373 GBM cell lines grown in normoxic (21% pO2) and hypoxic (< 1%pO2) conditions, transfected with HK2 siRNA followed by measurement of cell proliferation (BrdU), apoptosis (activated caspase 3/7, TUNEL, cytochrome c release) and viability (MTS assay).
Results: There exists a differential expression profile of glycolytic enzymes between the hypoxic center and relatively normoxic periphery of GBMs. Under hypoxic conditions, there is increased expression of HK2 at the mitochondrial membrane in GBM cells. In vitro HK2 knockdown led to decreased cell survival and increased apoptosis via the intrinsic mitochondrial pathway, as seen by increased mitochondrial release of cytochrome-C.
Conclusions: Increased expression of HK2 in the centre of GBMs promotes cell survival and confers resistance to apoptosis, as confirmed by in vitro studies. In vivo intracranial xenograft studies with injection of HK2-shRNA are currently being performed. HK2 and possibly other glycolytic enzymes may provide a target for enhanced therapeutic responsiveness thereby improving prognosis of patients with GBMs.
Regulation of huntingtin palmitoylation and its role in Huntington Diseases
Authors: Young F BJ , Hayden M R 
Published: May 2017

Huntington’s Disease (HD) is an autosomal dominant neurodegenerative disorder characterized by motor, cognitive, and psychiatric deficits and selective neuronal cell death. The causative mutation in HD is an expansion of the N-terminal polyglutamine tract in huntingtin (htt), which results in altered trafficking of mutant htt and enhanced toxicity to striatal neurons.
Post-translational modification by the lipid palmitate has been shown to play a critical role in the trafficking and function of many proteins, including htt. It has been previously demonstrated that huntingtin-interacting protein 14 (HIP14) is a palmitoyl transferase that palmitoylates htt. Previous characterization of HIP14 demonstrated a reduced interaction with mutant htt resulting in reduced palmitoylation, suggesting that palmitoylation may play a role in the pathogenesis of HD. Most recently, we have identified cysteine 214 as a major site of htt palmitoylation in the N-terminus of htt, close to the site of polyglutamine expansion. It was demonstrated that mutation of this site, rendering htt palmitoylation-resistant, results in increased neuronal toxicity, enhanced inclusion formation, and in altered trafficking of htt. Remarkably, mutation of the palmitoylation site in wild type htt also resulted in enhanced toxicity similar to that seen in mutant htt. Together, these previous studies suggest a critical role of palmitoylation in htt trafficking and function.
Based on this preliminary work, we are characterizing the enzymatic regulation of huntingtin palmitoylation. Exploring htt palmitoylation in a number of existing and new mouse models imparts key insights into how this process is regulated in vivo. We are also exploring the relationship between palmitoylation and other post-translational modifications of htt. These studies will lead to an understanding of the regulation of palmitoylation of huntingtin in vivo, as well as setting the precedent to understand the general role of palmitoylation in a wide range of other human diseases. Ultimately, this may lead to identification of new therapeutic targets and treatments for patients.

F.B.J.Y. is supported by a Canadian Institutes of Health Research Walter and Jessie Boyd & Charles Scriver - Child and Family Research Institute - UBC MD/PhD Studentship Award. She also receives funding from the Michael Smith Foundation for Health Research as a Junior Trainee.
Clinical predictors of facial nerve outcome after translabyrinthine resection of acoustic neuromas
Authors: Shamji Mohammed F. , Schramm David R. , Benoit Brien G. 
Published: May 2017

Purpose: The translabyrinthine approach to acoustic neuroma resection offers excellent exposure for facial nerve dissection with 95% preservation of anatomic continuity. Acceptable outcome in facial asymptomatic patients is reported at 64-90%, but transient postoperative deterioration often occurs. The objective of this study was to identify preoperative clinical presentation and intraoperative surgical findings that predispose patients to facial nerve dysfunction after acoustic neuroma surgery.

Methods: The charts of 128 consecutive translabyrinthine patients were examined retrospectively to identify new clinical and intraoperative predictors of facial nerve outcome. Postoperative evaluation of patients to normal function or mild asymmetry upon close inspection (House-Brackmann grades of I or II) was defined as an acceptable outcome, with obvious asymmetry to no movement (grades III to VI) defined as unacceptable. Intraoperative nerve stimulation was performed in all cases, and clinical grading was performed by a single neurosurgeon in all cases.

Results: Among patients with no preoperative facial nerve deficit, 87% had an acceptable result. Small size (P < 0.01) and low intraoperative nerve stimulation of
< 0.10 mA (P< 0.01) were reaffirmed as predictive of functional nerve preservation. Additionally, preoperative tinnitus (P = 0.03), short duration of hearing loss (P< 0. 01), and lack of subjective tumour adherence to the facial nerve (P = 0.02) were independently correlated with positive outcome.

Conclusions: Our experience with the translabyrinthine approach reveals the previously unestablished associations of facial nerve outcome to include presence of tinnitus and duration of hypoacusis. Independent predictors of tumour size and nerve stimulation thresholds were reaffirmed, and the subjective description of tumour adherence to the facial nerve making dissection more difficult appears to be important.
Mutations of the TGFBR2 gene in Chinese patients with Marfan-related syndrome
Authors: Chen JinLan , Li BuYun , Yang YiFeng , Hu JianGuo , Zhao TianLi , Gong YiBo , Tan ZhiPing 
Published: May 2017

Purpose: Transforming growth factor beta receptors II gene (TGFBR2) mutations associated with Marfan syndrome and Marfan-associated disorders have been investigated. However, such studies are limited in China. To obtain more information about TGFBR2 mutations, we analyzed 6 unrelated Chinese patients with Marfan-associated disorders and without ocular manifestation.

Methods: The genomic DNA from blood leukocytes of these 6 patients and their relatives was isolated, and the entire coding region of TGFBR2 was amplified using PCR. We determined the sequence of TGFBR2 with the ABI 3100 Genetic Analyzer.

Results: Three mutations were identified in TGFBR2. Two mutations were associated with Loeys-Dietz syndrome (LDS), which were distributed as following: one missense mutation R528C (caused by a 1582C > T substitution) and one polymorphism T315M (a rare SNP). The third mutation was a novel silent mutation associated with MFS2, which was K291K caused by an 873 C > T substitution.

Conclusions: The TGFBR2 gene missense mutations are possibly causative mutations of Loeys-Dietz syndrome. This result suggests an increase in the mutation spectrum of Marfan-related disorders in China and possibly world-wide.
Effects of montelukast on burn wound healing in a rat model
Authors: Turtay Muhammet G , Firat Cemal , Samdanci Emine , Oguzturk Hakan , Erbatur Serkan , Colak Cemil 
Published: May 2017

Purpose: Montelukast, a selective cysteinyl leukotriene D4-receptor antagonist, is used in the treatment of asthma. In a rat model, our aim was to investigate the effects of montelukast, alone or in combination with topical antibiotics, on local burn wound healing.

Methods: Rats were randomly allocated to four groups after local burn development: Group 1; rats were left to secondary healing without treatment, Group 2; a dose of 10 mg/kg montelukast was given by gastric gavage once a day for 10 days, Group 3; rats were treated with topical pomade (bacitracin neomycin sulphate), and Group 4; rats were treat with a combination of topical antibiotic and montelukast (10 mg/kg were given by gastric gavage once a day for 10 days). Skin biopsies were taken on days 3, 10, 14, and 20 relative to burn induction.

Results: Reepithelialization in the pomade and montelukast+pomade groups on the 10th day was significantly greater, in comparison with control and montelukast groups (p < 0.05). For the montelukast group, edema (on the 14th day) and angiogenesis, fibroblast proliferation, edema and macrophage infiltration (on the 20th day) were statistically improved in comparison with the control group (p < 0.05). For the montelukast+pomade group, angiogenesis, fibroblast proliferation and macrophage infiltration (on the 10th day), and angiogenesis, fibroblast proliferation, edema and macrophage infiltration (on the 14th and 20th days) were statistically improved in comparison with the control group (p < 0.05).

Conclusion: In conclusion, montelukast was effective on burn wound healing. Moreover, the effect was amplified when combined with topical antibiotics applied in the early stage of burn wound healing.
Plasma vitamin D levels and risk of metabolic syndrome in Canadians
Authors: Brenner Darren R , Arora Paul , Garcia-Bailo Bibiana , Wolever Thomas MS , Morrison Howard , El-Sohemy Ahmed , Karmali Mohamed , Badawi Alaa 
Published: May 2017

Purpose: Vitamin D deficiency has been implicated in susceptibility to the development of metabolic syndrome, obesity and type 2 diabetes mellitus. The present study aimed to quantify the association between vitamin D plasma level, the number of metabolic syndrome components and insulin resistance in Canadians.

Methods: Vitamin D plasma level and clinical data were determined from 1,818 subjects from the Canadian Health Measures Survey; a representative health survey of the general population of Canada conducted from 2007 to 2009. The definition of metabolic syndrome was based on the National Cholesterol Education Program, Adult Treatment Panel III criteria. Adjusted general linear models were used to estimate the association between vitamin D level and probability of having metabolic syndrome, as well as the association between plasma vitamin D and insulin resistance (homeostasis model assessment for insulin resistance, or HOMA-IR).

Results: The prevalence of metabolic syndrome in the study population was 8.9%. The number of metabolic syndrome components was inversely correlated with plasma vitamin D level (ρ= -0.1, p < 0.0001). Subjects in the highest vitamin D quartile had lower odds ratio of metabolic syndrome compared with their counterparts in the lowest vitamin D quartile (0.50, 95% CI= 0.24-1.06). Increasing plasma vitamin D level (by 10 nmol/L) was inversely associated with HOMA-IR score (β= -0.08, p=0.006) in a model adjusted for physical activity, smoking status, month of interview, age, sex and ethnicity.

Conclusion: Vitamin D plasma levels are associated with the occurrence of metabolic syndrome components and insulin resistance among Canadians and are linked to increased level of insulin resistance.