311 research outputs found

    Gut microbiota composition is associated with temperament traits in infants

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    Background: One of the key behavioral phenotypes in infancy are different temperament traits, and certain early life temperament traits have been shown to precede later mental health problems. Differences in the gut microbiota composition (GMC) have been suggested to link with neurodevelopment. For example, toddler temperament traits have been found to associate with differences in GMC; however, studies in infants are lacking although infancy is a rapid period of neurodevelopment as well as GM development. Thus, we aimed to investigate association between infant GMC and temperament. Methods: The study population (n = 301, 53% boys) was drawn from the FinnBrain Birth Cohort Study. Stool samples were collected from the 2.5-month-old infants and sequenced with 16S Illumina MiSeq platform. GMC taxonomic composition (at Genus and OTU level), observed sample clusters, diversity and richness were investigated in relation to the maternal reports of Infant Behavior Questionnaire -Revised (IBQ-R) at the age of 6 months. Results: Three sample clusters (Bifidobacterium/Enterobacteriaceae, Bacteroides, V. Dispar) based on GMC were identified, of which Bifidobacterium/Enterobacteriaceae–cluster presented with higher scores on the IBQ-R main dimension regulation and its subscale duration of orienting compared to Bacteroides-cluster. The clusters associated with temperament in a sex-dependent manner. The IBQ-R main dimension surgency (positive emotionality) was associated positively both with genus Bifidobacterium and Streptococcus. Alpha diversity had a negative association with negative emotionality and fear reactivity. Conclusion This is the first study demonstrating associations, but not causal connections, between GMC and temperament in young infants in a prospective design

    Deaths Among Adult Patients with Hypopituitarism: Hypocortisolism During Acute Stress, and De Novo Malignant Brain Tumors Contribute to an Increased Mortality.

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    Context:Patients with hypopituitarism have an increased standardized mortality rate. The basis for this has not been fully clarified.Objective:To investigate in detail the cause of death in a large cohort of patients with hypopituitarism subjected to long-term follow-up.Design and Methods:All-cause and cause-specific mortality in 1286 Swedish patients with hypopituitarism prospectively monitored in KIMS (Pfizer International Metabolic Database) 1995-2009 were compared to general population data in the Swedish National Cause of Death Registry. In addition, events reported in KIMS, medical records, and postmortem reports were reviewed.Main Outcome Measures:Standardized mortality ratios (SMR) were calculated, with stratification for gender, attained age, and calendar year during follow-up.Results:An excess mortality was found, 120 deaths vs 84.3 expected, SMR 1.42 (95% confidence interval: 1.18-1.70). Infections, brain cancer, and sudden death were associated with significantly increased SMRs (6.32, 9.40, and 4.10, respectively). Fifteen patients, all ACTH-deficient, died from infections. Eight of these patients were considered to be in a state of adrenal crisis in connection with death (medical reports and post-mortem examinations). Another 8 patients died from de novo malignant brain tumors, 6 of which had had a benign pituitary lesion at baseline. Six of these 8 subjects had received prior radiation therapy.Conclusion:Two important causes of excess mortality were identified: first, adrenal crisis in response to acute stress and intercurrent illness; second, increased risk of a late appearance of de novo malignant brain tumors in patients who previously received radiotherapy. Both of these causes may be in part preventable by changes in the management of pituitary disease

    Correlation of Structure, Function and Protein Dynamics in GH7 Cellobiohydrolases from \u3cem\u3eTrichoderma atroviride\u3c/em\u3e, \u3cem\u3eT. reesei\u3c/em\u3e and \u3cem\u3eT. harzianum\u3c/em\u3e

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    Background: The ascomycete fungus Trichoderma reesei is the predominant source of enzymes for industrial conversion of lignocellulose. Its glycoside hydrolase family 7 cellobiohydrolase (GH7 CBH) TreCel7A constitutes nearly half of the enzyme cocktail by weight and is the major workhorse in the cellulose hydrolysis process. The orthologs from Trichoderma atroviride (TatCel7A) and Trichoderma harzianum (ThaCel7A) show high sequence identity with TreCel7A, ~ 80%, and represent naturally evolved combinations of cellulose-binding tunnel-enclosing loop motifs, which have been suggested to influence intrinsic cellobiohydrolase properties, such as endo-initiation, processivity, and off-rate. Results: The TatCel7A, ThaCel7A, and TreCel7A enzymes were characterized for comparison of function. The catalytic domain of TatCel7A was crystallized, and two structures were determined: without ligand and with thio-cellotriose in the active site. Initial hydrolysis of bacterial cellulose was faster with TatCel7A than either ThaCel7A or TreCel7A. In synergistic saccharification of pretreated corn stover, both TatCel7A and ThaCel7A were more efficient than TreCel7A, although TatCel7A was more sensitive to thermal inactivation. Structural analyses and molecular dynamics (MD) simulations were performed to elucidate important structure/function correlations. Moreover, reverse conservation analysis (RCA) of sequence diversity revealed divergent regions of interest located outside the cellulose-binding tunnel of Trichoderma spp. GH7 CBHs. Conclusions: We hypothesize that the combination of loop motifs is the main determinant for the observed differences in Cel7A activity on cellulosic substrates. Fine-tuning of the loop flexibility appears to be an important evolutionary target in Trichoderma spp., a conclusion supported by the RCA data. Our results indicate that, for industrial use, it would be beneficial to combine loop motifs from TatCel7A with the thermostability features of TreCel7A. Furthermore, one region implicated in thermal unfolding is suggested as a primary target for protein engineering

    Hyperglycemia and redox status regulate RUNX2 DNA-binding and an angiogenic phenotype in endothelial cells

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    Angiogenesis is regulated by hyperglycemic conditions, which can induce cellular stress responses, reactive oxygen species (ROS), and anti-oxidant defenses that modulate intracellular signaling to prevent oxidative damage. The RUNX2 DNA-binding transcription factor is activated by a glucose-mediated intracellular pathway, plays an important role in endothelial cell (EC) function and angiogenesis, and is a target of oxidative stress. RUNX2 DNA-binding and EC differentiation in response to glucose were conserved in ECs from different tissues and inhibited by hyperglycemia, which stimulated ROS production through the aldose reductase glucose-utilization pathway. Furthermore, the redox status of cysteine and methionine residues regulated RUNX2 DNA-binding and reversal of oxidative inhibition was consistent with an endogenous Methionine sulfoxide reductase-A (MsrA) activity. Low molecular weight MsrA substrates and sulfoxide scavengers were potent inhibitors of RUNX2 DNA binding in the absence of oxidative stress, but acted as antioxidants to increase DNA binding in the presence of oxidants. MsrA was associated with RUNX2:DNA complexes, as measured by a sensitive, quantitative DNA-binding ELISA. The related RUNX2 protein family member, RUNX1, which contains an identical DNA-binding domain, was a catalytic substrate of recombinant MsrA. These findings define novel redox pathways involving aldose reductase and MsrA that regulate RUNX2 transcription factor activity and biological function in ECs. Targeting of these pathways could result in more effective strategies to alleviate the vascular dysfunction associated with diabetes or cancer

    HIV-1 with Multiple CCR5/CXCR4 Chimeric Receptor Use Is Predictive of Immunological Failure in Infected Children

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    BACKGROUND: HIV-1 R5 viruses are characterized by a large phenotypic variation, that is reflected by the mode of coreceptor use. The ability of R5 HIV-1 to infect target cells expressing chimeric receptors between CCR5 and CXCR4 (R5(broad) viruses), was shown to correlate with disease stage in HIV-1 infected adults. Here, we ask the question whether phenotypic variation of R5 viruses could play a role also in mother-to-child transmission (MTCT) of HIV-1 and pediatric disease progression. METHODOLOGY/PRINCIPAL FINDINGS: Viral isolates obtained from a total of 59 HIV-1 seropositive women (24 transmitting and 35 non transmitting) and 28 infected newborn children, were used to infect U87.CD4 cells expressing wild type or six different CCR5/CXCR4 chimeric receptors. HIV-1 isolates obtained from newborn infants had predominantly R5(narrow) phenotype (n = 20), but R5(broad) and R5X4 viruses were also found in seven and one case, respectively. The presence of R5(broad) and R5X4 phenotypes correlated significantly with a severe decline of the CD4+ T cells (CDC stage 3) or death within 2 years of age. Forty-three percent of the maternal R5 isolates displayed an R5(broad) phenotype, however, the presence of the R5(broad) virus was not predictive for MTCT of HIV-1. Of interest, while only 1 of 5 mothers with an R5X4 virus transmitted the dualtropic virus, 5 of 6 mothers carrying R5(broad) viruses transmitted viruses with a similar broad chimeric coreceptor usage. Thus, the maternal R5(broad) phenotype was largely preserved during transmission and could be predictive of the phenotype of the newborn's viral variant. CONCLUSIONS/SIGNIFICANCE: Our results show that R5(broad) viruses are not hampered in transmission. When transmitted, immunological failure occurs earlier than in children infected with HIV-1 of R5(narrow) phenotype. We believe that this finding is of utmost relevance for therapeutic interventions in pediatric HIV-1 infectio

    Oxidative Coupling as a Biomimetic Approach to the Synthesis of Scytonemin

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    The first total synthesis of the dimeric alkaloid pigment scytonemin is described. The key transformations In Its synthesis from 3-indole acetic acid are a Heck carbocyclization and a Suzuki-Miyaura cross-coupling, orchestrated In a stereospecific tandem fashion, followed by a biosynthetically inspired oxidative dimerization. The tandem sequence generates a tetracyclic (E)-3-(arylidene)-3,4-dihydrocyclopenta[b]indol-2(1H)-one that is subsequently dimerized into the unique homodimeric core structure of scytonemin

    Phenol-Soluble Modulin α Peptide Toxins from Aggressive Staphylococcus aureus Induce Rapid Formation of Neutrophil Extracellular Traps through a Reactive Oxygen Species-Independent Pathway

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    Neutrophils have the ability to capture and kill microbes extracellularly through the formation of neutrophil extracellular traps (NETs). These are DNA and protein structures that neutrophils release extracellularly and are believed to function as a defense mechanism against microbes. The classic NET formation process, triggered by, e.g., bacteria, fungi, or by direct stimulation of protein kinase C through phorbol myristate acetate, is an active process that takes several hours and relies on the production of reactive oxygen species (ROS) that are further modified by myeloperoxidase (MPO). We show here that NET-like structures can also be formed by neutrophils after interaction with phenol-soluble modulin α (PSMα) that are cytotoxic membrane-disturbing peptides, secreted from community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA). The PSMα-induced NETs contained the typical protein markers and were able to capture microbes. The PSMα-induced NET structures were disintegrated upon prolonged exposure to DNase-positive S. aureus but not on exposure to DNase-negative Candida albicans. Opposed to classic NETosis, PSMα-triggered NET formation occurred very rapidly, independently of ROS or MPO, and was also manifest at 4°C. These data indicate that rapid NETs release may result from cytotoxic membrane disturbance by PSMα peptides, a process that may be of importance for CA-MRSA virulence

    Up-regulation of cell cycle arrest protein BTG2 correlates with increased overall survival in breast cancer, as detected by immunohistochemistry using tissue microarray

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    <p>Abstract</p> <p>Background</p> <p>Previous studies have shown that the <it>ADIPOR1</it>, <it>ADORA1</it>, <it>BTG2 </it>and <it>CD46 </it>genes differ significantly between long-term survivors of breast cancer and deceased patients, both in levels of gene expression and DNA copy numbers. The aim of this study was to characterize the expression of the corresponding proteins in breast carcinoma and to determine their correlation with clinical outcome.</p> <p>Methods</p> <p>Protein expression was evaluated using immunohistochemistry in an independent breast cancer cohort of 144 samples represented on tissue microarrays. Fisher's exact test was used to analyze the differences in protein expression between dead and alive patients. We used Cox-regression multivariate analysis to assess whether the new markers predict the survival status of the patients better than the currently used markers.</p> <p>Results</p> <p>BTG2 expression was demonstrated in a significantly lower proportion of samples from dead patients compared to alive patients, both in overall expression (<it>P </it>= 0.026) and cell membrane specific expression (<it>P </it>= 0.013), whereas neither ADIPOR1, ADORA1 nor CD46 showed differential expression in the two survival groups. Furthermore, a multivariate analysis showed that a model containing BTG2 expression in combination with HER2 and Ki67 expression along with patient age performed better than a model containing the currently used prognostic markers (tumour size, nodal status, HER2 expression, hormone receptor status, histological grade, and patient age). Interestingly, BTG2 has previously been described as a tumour suppressor gene involved in cell cycle arrest and p53 signalling.</p> <p>Conclusions</p> <p>We conclude that high-level BTG2 protein expression correlates with prolonged survival in patients with breast carcinoma.</p

    Dapagliflozin and new-onset type 2 diabetes in patients with chronic kidney disease or heart failure:pooled analysis of the DAPA-CKD and DAPA-HF trials

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    Background: Chronic kidney disease and heart failure are insulin resistant states associated with a high incidence of diabetes. We assessed the effect of dapagliflozin on new-onset type 2 diabetes in a pooled analysis of patient-level data from the DAPA-CKD and DAPA-HF trials. Methods: This study is a pooled analysis of individual participant data from two phase 3, randomised, double-blind, placebo-controlled, multicentre, clinical trials. Participants with no history of diabetes and HbA1c less than 6·5% (48 mmol/mol) at baseline were included in this pooled analysis. New-onset type 2 diabetes was a prespecified exploratory endpoint in both DAPA-CKD and DAPA-HF trials and is the focus of this analysis. New-onset type 2 diabetes was identified by serial trial measurements of HbA1c (two consecutive values ≥6·5% [≥48 mmol/mol]) or following a clinical diagnosis of diabetes between trial visits. Time to new-onset type 2 diabetes was analysed in a Cox proportional Hazards model from random assignment to end of treatment. Findings: 4003 participants (1398 [34·9%] from the DADA-CKD trial and 2605 [65·1%] from the DAPA-HF trial) were included in our analysis: 1995 (49·8%) had received dapagliflozin and 2008 (50·2%) had received placebo. Over a median follow-up of 21·2 months (IQR 16·0 to 25·4), 126 (6·3%) of 2008 patients in the placebo group (event rate 3·9 per 100 patient-years) and 85 (4·3%) of 1995 patients in the dapagliflozin group (event rate 2·6 per 100 patient-years) developed type 2 diabetes (hazard ratio 0·67 [95% CI 0·51 to 0·88]; p=0·0040). There was no heterogeneity between studies (p interaction 0·77) and there was no clear evidence that the effect of dapagliflozin varied in prespecified subgroups including sex, age, glycaemic status, BMI, glomerular filtration rate, systolic blood pressure, and baseline cardiovascular medication use. More than 90% of the participants who developed type 2 diabetes had prediabetes at baseline (HbA1c 5·7% to 6·4% [39 to 46 mmol/mol]). Mean HbA1c remained unchanged (placebo-adjusted change in the dapagliflozin group of −0·01% [95% CI −0·03 to 0·01], −0·1 mmol/mol [95% CI −0·3 to 0·1] at 12 months). Interpretation: Treatment with dapagliflozin reduced the incidence of new-onset type 2 diabetes in participants with chronic kidney disease and HF without a reduction in HbA1c. Funding: AstraZeneca
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