180 research outputs found
Skeletal muscle high energy phosphate metabolism in patients with obesity and impaired fasting blood glucose
The REFOLD database: a tool for the optimization of protein expression and refolding
A large proportion of proteins expressed in Escherichia coli form inclusion bodies and thus require renaturation to attain a functional conformation for analysis. In this process, identifying and optimizing the refolding conditions and methodology is often rate limiting. In order to address this problem, we have developed REFOLD, a web-accessible relational database containing the published methods employed in the refolding of recombinant proteins. Currently, REFOLD contains >300 entries, which are heavily annotated such that the database can be searched via multiple parameters. We anticipate that REFOLD will continue to grow and eventually become a powerful tool for the optimization of protein renaturation. REFOLD is freely available at
Metaanalysis of the Performance of a Combined Treponemal and Nontreponemal Rapid Diagnostic Test for Syphilis and Yaws
BACKGROUND: The human treponematoses are important causes of
disease. Mother-to-child transmission of syphilis remains a
major cause of stillbirth and neonatal death. There are also
almost 100 000 cases of endemic treponemal disease reported
annually, predominantly yaws. Rapid diagnostic tests (RDTs)
would improve access to screening for these diseases. Most RDTs
cannot distinguish current and previous infection. The Dual Path
Platform (DPP) Syphilis Screen & Confirm test includes both
a treponemal (T1) and nontreponemal (T2) component and may
improve the accuracy of diagnosis. METHODS: We conducted a
metaanalysis of published and unpublished evaluations of the
DPP-RDT for the diagnosis of syphilis and yaws. We calculated
the sensitivity, specificity, and overall agreement of the test
compared with reference laboratory tests. RESULTS: Nine
evaluations, including 7267 tests, were included. Sensitivity
was higher in patients with higher titer rapid plasma reagin
(>/=1:16) for both the T1 (98.2% vs 90.1%, P < .0001) and
the T2 component (98.2% vs 80.6%, P < .0001). Overall
agreement between the DPP test and reference serology was 85.2%
(84.4%-86.1%). Agreement was highest for high-titer active
infection and lowest for past infection. CONCLUSIONS: The RDT
has good sensitivity and specificity of the treponemal and
nontreponemal components both in cases of suspected syphilis and
yaws, although the sensitivity is decreased at lower antibody
titers
Two repetition time saturation transfer (TwiST) with spill-over correction to measure creatine kinase reaction rates in human hearts
Comparative efficacy of low-dose versus standard-dose azithromycin for patients with yaws: a randomised non-inferiority trial in Ghana and Papua New Guinea
Background: A dose of 30 mg/kg of azithromycin is recommended for treatment of yaws, a disease targeted for global eradication. Treatment with 20 mg/kg of azithromycin is recommended for the elimination of trachoma as a public health problem. In some settings, these diseases are co-endemic. We aimed to determine the efficacy of 20 mg/kg of azithromycin compared with 30 mg/kg azithromycin for the treatment of active and latent yaws. Methods: We did a non-inferiority, open-label, randomised controlled trial in children aged 6–15 years who were recruited from schools in Ghana and schools and the community in Papua New Guinea. Participants were enrolled based on the presence of a clinical lesion that was consistent with infectious primary or secondary yaws and a positive rapid diagnostic test for treponemal and non-treponemal antibodies. Participants were randomly assigned (1:1) to receive either standard-dose (30 mg/kg) or low-dose (20 mg/kg) azithromycin by a computer-generated random number sequence. Health-care workers assessing clinical outcomes in the field were not blinded to the patient's treatment, but investigators involved in statistical or laboratory analyses and the participants were blinded to treatment group. We followed up participants at 4 weeks and 6 months. The primary outcome was cure at 6 months, defined as lesion healing at 4 weeks in patients with active yaws and at least a four-fold decrease in rapid plasma reagin titre from baseline to 6 months in patients with active and latent yaws. Active yaws was defined as a skin lesion that was positive for Treponema pallidum ssp pertenue in PCR testing. We used a non-inferiority margin of 10%. This trial was registered with ClinicalTrials.gov, number NCT02344628.
Findings: Between June 12, 2015, and July 2, 2016, 583 (65·1%) of 895 children screened were enrolled; 292 patients were assigned a low dose of azithromycin and 291 patients were assigned a standard dose of azithromycin. 191 participants had active yaws and 392 had presumed latent yaws. Complete follow-up to 6 months was available for 157 (82·2%) of 191 patients with active yaws. In cases of active yaws, cure was achieved in 61 (80·3%) of 76 patients in the low-dose group and in 68 (84·0%) of 81 patients in the standard-dose group (difference 3·7%; 95% CI −8·4 to 15·7%; this result did not meet the non-inferiority criterion). There were no serious adverse events reported in response to treatment in either group. The most commonly reported adverse event at 4 weeks was gastrointestinal upset, with eight (2·7%) participants in each group reporting this symptom.
Interpretation:
In this study, low-dose azithromycin did not meet the prespecified non-inferiority margin compared with standard-dose azithromycin in achieving clinical and serological cure in PCR-confirmed active yaws. Only a single participant (with presumed latent yaws) had definitive serological failure. This work suggests that 20 mg/kg of azithromycin is probably effective against yaws, but further data are needed
Metabolic manipulation in chronic heart failure: study protocol for a randomised controlled trial
<p>Abstract</p> <p>Background</p> <p>Heart failure is a major cause of morbidity and mortality in society. Current medical therapy centres on neurohormonal modulation with angiotensin converting enzyme inhibitors and β-blockers. There is growing evidence for the use of metabolic manipulating agents as adjunctive therapy in patients with heart failure. We aim to determine the effect of perhexiline on cardiac energetics and alterations in substrate utilisation in patients with non-ischaemic dilated cardiomyopathy.</p> <p>Methods</p> <p>A multi-centre, prospective, randomised double-blind, placebo-controlled trial of 50 subjects with non-ischaemic dilated cardiomyopathy recruited from University Hospital Birmingham NHS Foundation Trust and Cardiff and Vale NHS Trust. Baseline investigations include magnetic resonance spectroscopy to assess cardiac energetic status, echocardiography to assess left ventricular function and assessment of symptomatic status. Subjects are then randomised to receive 200 mg perhexiline maleate or placebo daily for 4 weeks with serum drug level monitoring. All baseline investigations will be repeated at the end of the treatment period. A subgroup of patients will undergo invasive investigations with right and left heart catheterisation to calculate respiratory quotient, and mechanical efficiency. The primary endpoint is an improvement in the phosphocreatine to adenosine triphosphate ratio at 4 weeks. Secondary end points are: i) respiratory quotient; ii) mechanical efficiency; iii) change in left ventricular (LV) function.</p> <p>Trial Registration</p> <p>ClinicalTrials.gov: <a href="http://www.clinicaltrials.gov/ct2/show/NCT00841139">NCT00841139</a></p> <p>ISRCTN: <a href="http://www.controlled-trials.com/ISRCTN2887836">ISRCTN2887836</a></p
The effect of a comprehensive typhoid conjugate vaccine campaign on antimicrobial prescribing in children in Harare, Zimbabwe: a mixed methods study.
BACKGROUND: Vaccines prevent infections and could subsequently reduce antimicrobial use. A 1-week mass vaccination campaign was done with Typbar-TCV (Bharat Biotech, Hyderabad, India) between Feb 25 and March 4, 2019. We investigated whether this typhoid conjugate vaccine campaign could affect antimicrobial prescribing in children presenting to primary care in Harare, Zimbabwe. METHODS: In this mixed methods study, data for acute paediatric outpatient consultations between Jan 1, 2018, and March 31, 2020, were collected from five clinics in Harare. Interrupted time series analysis was done to compare prescription data before and after the campaign. To contextualise findings, qualitative data were collected between April 20, 2021, and July 20, 2022, comprising ethnographic research (ie, workshops, surveys, observations, and interviews) in 14 clinics. Ethnographic data were used for thematic analysis. The primary outcome was monthly antimicrobial prescriptions in children aged 6 months to 15 years, normalised by the number of trauma events in all age groups. FINDINGS: In the data collection period, 27 107 paediatric consultations were recorded. 17 951 (66·2%) of 27 107 children were prescribed antimicrobials. Despite the perceived reduction in typhoid cases and a decreasing trend in the prescription of antimicrobials commonly used to treat typhoid (ie, ciprofloxacin and azithromycin), mass vaccination with Typbar-TCV did not affect the total rate of antimicrobials (adjusted rate ratio, 1·20, 95% CI 0·70-2·05, p=0·51) or the rate of typhoid antimicrobials prescribed (0·93, 0·44-1·96, p=0·85). Unsafe water sources and insufficient diagnostic services were reported to contribute to the continued disease burden and antimicrobial prescription. INTERPRETATION: Non-specific febrile illness caused by confirmed or suspected typhoid is a common cause of antimicrobial use in endemic areas. Although effective in preventing typhoid fever, we were unable to identify any effect of Typbar-TCV on antimicrobial prescribing. Ethnographic research showed the effect of contextual factors on antimicrobial prescribing, including concerns regarding safe water access, appropriate sewage disposal, health-care and diagnostic availability. To realise effects beyond disease burden reduction, holistic approaches addressing these concerns are needed so that the value of vaccines mitigating the effects of antimicrobial use as a driver of antimicrobial resistance is fully achieved. FUNDING: Wellcome Trust. TRANSLATION: For the Shona translation of the abstract see Supplementary Materials section
Health-related quality of life results from the phase III CheckMate 067 study
Background Nivolumab, a monoclonal antibody of immune checkpoint programmed death 1 on T cells (PD-1), combined with ipilimumab, an immune checkpoint cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) inhibitor, as combination therapy on the one hand and nivolumab as monotherapy on the other, have both demonstrated improved efficacy compared with ipilimumab alone in the CheckMate 067 study. However, the combination resulted in a higher frequency of grade 3/4 adverse events (AEs), which could result in diminished health-related quality of life (HRQoL). Here we report analyses of HRQoL for patients with advanced melanoma in clinical trial CheckMate 067.Patients and methods HRQoL was assessed at weeks 1 and 5 per 6-week cycle for the first 6 months, once every 6 weeks thereafter, and at two follow-up visits using the European Organization for Research and Treatment of Care Core Quality of Life Questionnaire and the EuroQoL Five Dimensions Questionnaire. In addition to the randomised population, patient subgroups, including BRAF mutation status, partial or complete response, treatment-related AEs of grade 3/4, and those who discontinued due to any reason and due to an AE, were investigated.Results Nivolumab and ipilimumab combination and nivolumab alone both maintained HRQoL, and no clinically meaningful deterioration was observed over time compared with ipilimumab. In addition, similar results were observed across patient subgroups, and no clinically meaningful changes in HRQoL were observed during follow-up visits for patients who discontinued due to any cause.Conclusion These results further support the clinical benefit of nivolumab monotherapy and nivolumab and ipilimumab combination therapy in patients with advanced melanoma. The finding that the difference in grade 3/4 AEs between the arms did not translate into clinically meaningful differences in the reported HRQoL may be relevant in the clinical setting.Study number NCT01844505
KSR2 mutations are associated with obesity, insulin resistance, and impaired cellular fuel oxidation.
Kinase suppressor of Ras 2 (KSR2) is an intracellular scaffolding protein involved in multiple signaling pathways. Targeted deletion of Ksr2 leads to obesity in mice, suggesting a role in energy homeostasis. We explored the role of KSR2 in humans by sequencing 2,101 individuals with severe early-onset obesity and 1,536 controls. We identified multiple rare variants in KSR2 that disrupt signaling through the Raf-MEKERK pathway and impair cellular fatty acid oxidation and glucose oxidation in transfected cells; effects that can be ameliorated by the commonly prescribed antidiabetic drug, metformin. Mutation carriers exhibit hyperphagia in childhood, low heart rate, reduced basal metabolic rate and severe insulin resistance. These data establish KSR2 as an important regulator of energy intake, energy expenditure, and substrate utilization in humans. Modulation of KSR2-mediated effects may represent a novel therapeutic strategy for obesity and type 2 diabetes.This work was supported by the Wellcome Trust
(098497/Z/12/Z; 077016/Z/05/Z; 096106/Z/11/Z) (ISF and LRP), Medical
Research Council (MC_U106179471) (NW), NIHR Cambridge Biomedical
Research Centre (ISF, IB and SOR), and European Research Council (ISF).
This study makes use of data generated by the UK10K Consortium
(WT091310). A full list of the investigators who contributed to the generation
of the data is available from http://www.UK10K.org.This is the final published version. It first appeared at http://www.cell.com/abstract/S0092-8674%2813%2901276-2
Early acquisition and high nasopharyngeal co-colonisation by Streptococcus pneumoniae and three respiratory pathogens amongst Gambian new-borns and infants
BACKGROUND: Although Haemophilus influenzae type b (Hib), Staphylococcus aureus and Moraxella catarrhalis are important causes of invasive and mucosal bacterial disease among children, co-carriage with Streptococcus pneumoniae during infancy has not been determined in West Africa. METHODS: Species specific PCR was applied to detect each microbe using purified genomic DNA from 498 nasopharyngeal (NP) swabs collected from 30 Gambian neonates every two weeks from 0 to 6 months and bi-monthly up to 12 months. RESULTS: All infants carried S. pneumoniae, H. influenzae and M. catarrhalis at several time points during infancy. S.pneumoniae co-colonized the infant nasopharynx with at least one other pathogen nine out of ten times. There was early colonization of the newborns and neonates, the average times to first detection were 5, 7, 3 and 14 weeks for S. pneumoniae, H. influenzae, M. catarrhalis and S. aureus respectively. The prevalence of S. pneumoniae, H. influenzae and M. catarrhalis increased among the neonates and exceeded 80% by 13, 15 and 23 weeks respectively. In contrast, the prevalence of S. aureus decreased from 50% among the newborns to 20% amongst nine-week old neonates. S. pneumoniae appeared to have a strong positive association with H. influenzae (OR 5.03; 95% CI 3.02, 8.39; p<0.01) and M. catarrhalis (OR 2.20; 95% CI 1.29; p<0.01) but it was negatively associated with S. aureus (OR 0.53; 95% CI 0.30, 0.94; p=0.03). CONCLUSION: This study shows early acquisition and high co-carriage of three important respiratory pathogens with S. pneumoniae in the nasopharyngeal mucosa among Gambian neonates and infants. This has important potential implications for the aetiology of respiratory polymicrobial infections, biofilm formation and vaccine strategies
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