163 research outputs found

    Grifonin-1: A Small HIV-1 Entry Inhibitor Derived from the Algal Lectin, Griffithsin

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    Background: Griffithsin, a 121-residue protein isolated from a red algal Griffithsia sp., binds high mannose N-linked glycans of virus surface glycoproteins with extremely high affinity, a property that allows it to prevent the entry of primary isolates and laboratory strains of T- and M-tropic HIV-1. We used the sequence of a portion of griffithsin's sequence as a design template to create smaller peptides with antiviral and carbohydrate-binding properties. Methodology/Results: The new peptides derived from a trio of homologous β-sheet repeats that comprise the motifs responsible for its biological activity. Our most active antiviral peptide, grifonin-1 (GRFN-1), had an EC50 of 190.8±11.0 nM in in vitro TZM-bl assays and an EC50 of 546.6±66.1 nM in p24gag antigen release assays. GRFN-1 showed considerable structural plasticity, assuming different conformations in solvents that differed in polarity and hydrophobicity. Higher concentrations of GRFN-1 formed oligomers, based on intermolecular β-sheet interactions. Like its parent protein, GRFN-1 bound viral glycoproteins gp41 and gp120 via the N-linked glycans on their surface. Conclusion: Its substantial antiviral activity and low toxicity in vitro suggest that GRFN-1 and/or its derivatives may have therapeutic potential as topical and/or systemic agents directed against HIV-1

    Prevalence of 22q11.2 microdeletion in 146 patients with cardiac malformation in a referral hospital of North India

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    <p>Abstract</p> <p>Background</p> <p>The 22q11.2 microdeletion syndrome is a common condition that is associated with cardiac as well as extra-cardiac manifestations. Its prevalence and manifestations from north India has not been reported. This study was designed to determine the prevalence and ability of clinical criteria to predict 22q11.2 microdeletion.</p> <p>Methods</p> <p>A total of 146 cases of cardiac malformation requiring tertiary care at a teaching hospital were prospectively screened for 22q11.2 microdeletion using fluorescence in situ hybridization test. Detailed clinical information was obtained as per guidelines of Tobias, <it>et al </it>(1999).</p> <p>Results</p> <p>Nine out of 146 patients (6.16%) was found to have 22q11.2 microdeletion. All the positive patients showed the presence of extra-cardiac features of 22q11.2 microdeletion syndrome. None of the cases with isolated cardiac defect were positive for microdeletion.</p> <p>Conclusions</p> <p>It seems that 22q11.2 microdeletion syndrome is over-suspected in children with isolated congenital heart defects. Screening for 22q11.2 microdeletion should be considered in those cardiac malformation cases which have extra-cardiac manifestations in the form of facial dysmorphism and hypocalcaemia.</p

    Association between the NBS1 E185Q polymorphism and cancer risk: a meta-analysis

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    <p>Abstract</p> <p>Background</p> <p>NBS1 is a key DNA repair protein in the homologous recombination repair pathway and a signal modifier in the intra-S phase checkpoint that plays important roles in maintaining genomic stability. The <it>NBS1 </it>8360G>C (<it>Glu185Gln</it>) is one of the most commonly studied polymorphisms of the gene for their association with risk of cancers, but the results are conflicting.</p> <p>Methods</p> <p>We performed a meta-analysis using 16 eligible case-control studies (including 17 data sets) with a total of 9,734 patients and 10,325 controls to summarize the data on the association between the <it>NBS1 </it>8360G>C (E185Q) polymorphism and cancer risk.</p> <p>Results</p> <p>Compared with the common 8360GG genotype, the carriers of variant genotypes (i.e., 8360 GC/CC) had a 1.06-fold elevated risk of cancer (95% CI = 1.00–1.12, <it>P </it>= 0.05) in a dominant genetic model as estimated in a fixed effect model. However, the association was not found in an additive genetic model (CC <it>vs </it>GG) (odds ratio, OR = 0.98, 95% CI = 0.85–1.13, <it>P </it>= 0.78) nor in a recessive genetic model (CC <it>vs </it>GC +GG) (OR = 0.94, 95% CI = 0.82–1.07, <it>P </it>= 0.36). The effect of the 8360G>C (E185Q) polymorphism was further evaluated in stratification analysis. It was demonstrated that the increased risk of cancer associated with 8360G>C variant genotypes was more pronounced in the Caucasians (OR = 1.07, 95% CI = 1.01–1.14, <it>P </it>= 0.03).</p> <p>Conclusion</p> <p>Our meta-analysis suggests that the <it>NBS1 </it>E185Q variant genotypes (8360 <it>GC/CC</it>) might be associated with an increased risk of cancer, especially in Caucasians.</p

    Clinical Features and Natural History of Preadolescent Nonsyndromic Hypertrophic Cardiomyopathy

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    BACKGROUND Up to one-half of childhood sarcomeric hypertrophic cardiomyopathy (HCM) presents before the age of 12 years, but this patient group has not been systematically characterized. OBJECTIVES The aim of this study was to describe the clinical presentation and natural history of patients presenting with nonsyndromic HCM before the age of 12 years. METHODS Data from the International Paediatric Hypertrophic Cardiomyopathy Consortium on 639 children diagnosed with HCM younger than 12 years were collected and compared with those from 568 children diagnosed between 12 and 16 years. RESULTS At baseline, 339 patients (53.6%) had family histories of HCM, 132 (20.9%) had heart failure symptoms, and 250 (39.2%) were prescribed cardiac medications. The median maximal left ventricular wall thickness z-score was 8.7 (IQR: 5.3-14.4), and 145 patients (27.2%) had left ventricular outflow tract obstruction. Over a median follow-up period of 5.6 years (IQR: 2.3-10.0 years), 42 patients (6.6%) died, 21 (3.3%) underwent cardiac transplantation, and 69 (10.8%) had life-threatening arrhythmic events. Compared with those presenting after 12 years, a higher proportion of younger patients underwent myectomy (10.5% vs 7.2%; P = 0.045), but fewer received primary prevention implantable cardioverter-defibrillators (18.9% vs 30.1%; P = 0.041). The incidence of mortality or life-threatening arrhythmic events did not differ, but events occurred at a younger age. CONCLUSIONS Early-onset childhood HCM is associated with a comparable symptom burden and cardiac phenotype as in patients presenting later in childhood. Long-term outcomes including mortality did not differ by age of presentation, but patients presenting at younger than 12 years experienced adverse events at younger ages. (C) 2022 The Authors. Published by Elsevier on behalf of the American College of Cardiology Foundation.Peer reviewe

    Positioning pharmacists’ roles in primary health care: a discourse analysis of the compensation plan in Alberta, Canada

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    Abstract Background A comprehensive Compensation Plan for pharmacy services delivered by community pharmacists was implemented in Alberta, Canada in July 2012. Services covered by the Compensation Plan include care planning services, prescribing services such as adapting prescriptions, and administering a drug or publicly-funded vaccine by injection. Understanding how the Compensation Plan was framed and communicated provides insight into the roles of pharmacists and the potential influence of language on the implementation of services covered by the Compensation Plan by Albertan pharmacists. The objective of this study is to examine the positioning of pharmacists’ roles in documents used to communicate the Compensation Plan to Albertan pharmacists and other audiences. Methods Publicly available documents related to the Compensation Plan, such as news releases or reports, published between January 2012 and December 2015 were obtained from websites such as the Government of Alberta, Alberta Blue Cross, the Alberta College of Pharmacists, the Alberta Pharmacists’ Association, and the Blueprint for Pharmacy. Searches of the Canadian Newsstand database and Google identified additional documents. Discourse analysis was performed using social positioning theory to explore how pharmacists’ roles were constructed in communications about the Compensation Plan. Results In total, 65 publicly available documents were included in the analysis. The Compensation Plan was put forward as a framework for payment for professional services and formal legitimization of pharmacists’ changing professional roles. The discourse associated with the Compensation Plan positioned pharmacists’ roles as: (1) expanding to include services such as medication management for chronic diseases, (2) contributing to primary health care by providing access to services such as prescription renewals and immunizations, and (3) collaborating with other health care team members. Pharmacists’ changing roles were positioned in alignment with the aims of primary health care. Conclusions Social positioning theory provides a useful lens to examine the dynamic and evolving roles of pharmacists. This study provides insight into how communications regarding the Compensation Plan in Alberta, Canada positioned pharmacists’ changing roles in the broader context of changes to primary health care delivery. Our findings may be useful for other jurisdictions considering implementation of remunerated clinical services provided by pharmacists

    Mannose-rich glycosylation patterns on HIV-1 subtype C gp120 and sensitivity to the lectins, Griffithsin, Cyanovirin-N and Scytovirin.

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    Griffithsin (GRFT), Cyanovirin-N (CV-N) and Scytovirin (SVN) are lectins that inhibit HIV-1 infection by binding to multiple mannose-rich glycans on the HIV-1 envelope glycoproteins (Env). Here we show that these lectins neutralize subtype C primary virus isolates in addition to Env-pseudotyped viruses obtained from plasma and cervical vaginal lavages. Among 15 subtype C pseudoviruses, the median IC50 values were 0.4, 1.8 and 20.1 nM for GRFT, CV-N and SVN, respectively, similar to what was found for subtype B and A. Analysis of Env sequences suggested that concomitant lack of glycans at positions 234 and 295 resulted in natural resistance to these compounds, which was confirmed by site-directed mutagenesis. Furthermore, the binding sites for these lectins overlapped that of the 2G12 monoclonal antibody epitope, which is generally absent on subtype C Env. This data support further research on these lectins as potential microbicides in the context of HIV-1 subtype C infection

    Relationship Between Maximal Left Ventricular Wall Thickness and Sudden Cardiac Death in Childhood Onset Hypertrophic Cardiomyopathy

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    Background: Maximal left ventricular wall thickness (MLVWT) is a risk factor for sudden cardiac death (SCD) in hypertrophic cardiomyopathy (HCM). In adults, the severity of left ventricular hypertrophy has a nonlinear relationship with SCD, but it is not known whether the same complex relationship is seen in childhood. The aim of this study was to describe the relationship between left ventricular hypertrophy and SCD risk in a large international pediatric HCM cohort. Methods: The study cohort comprised 1075 children (mean age, 10.2 years [+/- 4.4]) diagnosed with HCM (1-16 years) from the International Paediatric Hypertrophic Cardiomyopathy Consortium. Anonymized, noninvasive clinical data were collected from baseline evaluation and follow-up, and 5-year estimated SCD risk was calculated (HCM Risk-Kids). Results: MLVWT Z score was = 10 to = 20 in 143 (13.3%). Higher MLVWT Z scores were associated with heart failure symptoms, unexplained syncope, left ventricular outflow tract obstruction, left atrial dilatation, and nonsustained ventricular tachycardia. One hundred twenty-two patients (71.3%) with MLVWT Z score >= 20 had coexisting risk factors for SCD. Over a median follow-up of 4.9 years (interquartile range, 2.3-9.3), 115 (10.7%) had an SCD event. Freedom from SCD event at 5 years for those with MLVWT Z scores = 10 to = 20 was 95.6%, 87.4%, and 86.0, respectively. The estimated SCD risk at 5 years had a nonlinear, inverted U-shaped relationship with MLVWT Z score, peaking at Z score +23. The presence of coexisting risk factors had a summative effect on risk. Conclusions: In children with HCM, an inverted U-shaped relationship exists between left ventricular hypertrophy and estimated SCD risk. The presence of additional risk factors has a summative effect on risk. While MLVWT is important for risk stratification, it should not be used either as a binary variable or in isolation to guide implantable cardioverter defibrillator implantation decisions in children with HCM.Peer reviewe
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