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1.
Nature ; 626(8001): 1094-1101, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38383783

RESUMO

Persistent SARS-CoV-2 infections may act as viral reservoirs that could seed future outbreaks1-5, give rise to highly divergent lineages6-8 and contribute to cases with post-acute COVID-19 sequelae (long COVID)9,10. However, the population prevalence of persistent infections, their viral load kinetics and evolutionary dynamics over the course of infections remain largely unknown. Here, using viral sequence data collected as part of a national infection survey, we identified 381 individuals with SARS-CoV-2 RNA at high titre persisting for at least 30 days, of which 54 had viral RNA persisting at least 60 days. We refer to these as 'persistent infections' as available evidence suggests that they represent ongoing viral replication, although the persistence of non-replicating RNA cannot be ruled out in all. Individuals with persistent infection had more than 50% higher odds of self-reporting long COVID than individuals with non-persistent infection. We estimate that 0.1-0.5% of infections may become persistent with typically rebounding high viral loads and last for at least 60 days. In some individuals, we identified many viral amino acid substitutions, indicating periods of strong positive selection, whereas others had no consensus change in the sequences for prolonged periods, consistent with weak selection. Substitutions included mutations that are lineage defining for SARS-CoV-2 variants, at target sites for monoclonal antibodies and/or are commonly found in immunocompromised people11-14. This work has profound implications for understanding and characterizing SARS-CoV-2 infection, epidemiology and evolution.


Assuntos
COVID-19 , Inquéritos Epidemiológicos , Infecção Persistente , SARS-CoV-2 , Humanos , Substituição de Aminoácidos , Anticorpos Monoclonais/imunologia , COVID-19/epidemiologia , COVID-19/virologia , Evolução Molecular , Hospedeiro Imunocomprometido/imunologia , Mutação , Infecção Persistente/epidemiologia , Infecção Persistente/virologia , Síndrome de COVID-19 Pós-Aguda/epidemiologia , Síndrome de COVID-19 Pós-Aguda/virologia , Prevalência , RNA Viral/análise , RNA Viral/genética , SARS-CoV-2/química , SARS-CoV-2/classificação , SARS-CoV-2/genética , SARS-CoV-2/imunologia , SARS-CoV-2/isolamento & purificação , Seleção Genética , Autorrelato , Fatores de Tempo , Carga Viral , Replicação Viral
2.
Am J Epidemiol ; 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38808625

RESUMO

Detecting and quantifying changes in growth rates of infectious diseases is vital to informing public health strategy and can inform policymakers' rationale for implementing or continuing interventions aimed at reducing impact. Substantial changes in SARS-CoV-2 prevalence with emergence of variants provides opportunity to investigate different methods to do this. We included PCR results from all participants in the UK's COVID-19 Infection Survey between August 2020-June 2022. Change-points for growth rates were identified using iterative sequential regression (ISR) and second derivatives of generalised additive models (GAMs). Consistency between methods and timeliness of detection were compared. Of 8,799,079 visits, 147,278 (1.7%) were PCR-positive. Change-points associated with emergence of major variants were estimated to occur a median 4 days earlier (IQR 0-8) in GAMs versus ISR. When estimating recent change-points using successive data periods, four change-points (4/96) identified by GAMs were not found when adding later data or by ISR. Change-points were detected 3-5 weeks after they occurred in both methods but could be detected earlier within specific subgroups. Change-points in growth rates of SARS-CoV-2 can be detected in near real-time using ISR and second derivatives of GAMs. To increase certainty about changes in epidemic trajectories both methods could be run in parallel.

3.
BMC Med ; 22(1): 143, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38532381

RESUMO

BACKGROUND: Syndromic surveillance often relies on patients presenting to healthcare. Community cohorts, although more challenging to recruit, could provide additional population-wide insights, particularly with SARS-CoV-2 co-circulating with other respiratory viruses. METHODS: We estimated the positivity and incidence of SARS-CoV-2, influenza A/B, and RSV, and trends in self-reported symptoms including influenza-like illness (ILI), over the 2022/23 winter season in a broadly representative UK community cohort (COVID-19 Infection Survey), using negative-binomial generalised additive models. We estimated associations between test positivity and each of the symptoms and influenza vaccination, using adjusted logistic and multinomial models. RESULTS: Swabs taken at 32,937/1,352,979 (2.4%) assessments tested positive for SARS-CoV-2, 181/14,939 (1.2%) for RSV and 130/14,939 (0.9%) for influenza A/B, varying by age over time. Positivity and incidence peaks were earliest for RSV, then influenza A/B, then SARS-CoV-2, and were highest for RSV in the youngest and for SARS-CoV-2 in the oldest age groups. Many test positives did not report key symptoms: middle-aged participants were generally more symptomatic than older or younger participants, but still, only ~ 25% reported ILI-WHO and ~ 60% ILI-ECDC. Most symptomatic participants did not test positive for any of the three viruses. Influenza A/B-positivity was lower in participants reporting influenza vaccination in the current and previous seasons (odds ratio = 0.55 (95% CI 0.32, 0.95)) versus neither season. CONCLUSIONS: Symptom profiles varied little by aetiology, making distinguishing SARS-CoV-2, influenza and RSV using symptoms challenging. Most symptoms were not explained by these viruses, indicating the importance of other pathogens in syndromic surveillance. Influenza vaccination was associated with lower rates of community influenza test positivity.


Assuntos
COVID-19 , Influenza Humana , Infecções por Vírus Respiratório Sincicial , Viroses , Pessoa de Meia-Idade , Humanos , Influenza Humana/epidemiologia , SARS-CoV-2 , Estações do Ano , Autorrelato , Vírus Sinciciais Respiratórios , Reino Unido , Infecções por Vírus Respiratório Sincicial/epidemiologia
4.
BMC Public Health ; 24(1): 1890, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39010057

RESUMO

BACKGROUND: An outbreak of acute severe hepatitis of unknown aetiology (AS-Hep-UA) in children during 2022 was subsequently linked to infections with adenovirus-associated virus 2 and other 'helper viruses', including human adenovirus. It is possible that evidence of such an outbreak could be identified at a population level based on routine data captured by electronic health records (EHR). METHODS: We used anonymised EHR to collate retrospective data for all emergency presentations to Oxford University Hospitals NHS Foundation Trust in the UK, between 2016-2022, for all ages from 18 months and older. We investigated clinical characteristics and temporal distribution of presentations of acute hepatitis and of adenovirus infections based on laboratory data and clinical coding. We relaxed the stringent case definition adopted during the AS-Hep-UA to identify all cases of acute hepatitis with unknown aetiology (termed AHUA). We compared events within the outbreak period (defined as 1st Oct 2021-31 Aug 2022) to the rest of our study period. RESULTS: Over the study period, there were 903,433 acute presentations overall, of which 391 (0.04%) were classified as AHUA. AHUA episodes had significantly higher critical care admission rates (p < 0.0001, OR = 41.7, 95% CI:26.3-65.0) and longer inpatient admissions (p < 0.0001) compared with the rest of the patient population. During the outbreak period, significantly more adults (≥ 16 years) were diagnosed with AHUA (p < 0.0001, OR = 3.01, 95% CI: 2.20-4.12), and there were significantly more human adenovirus (HadV) infections in children (p < 0.001, OR = 1.78, 95% CI:1.27-2.47). There were also more HAdV tests performed during the outbreak (p < 0.0001, OR = 1.27, 95% CI:1.17-1.37). Among 3,707 individuals who were tested for HAdV, 179 (4.8%) were positive. However, there was no evidence of more acute hepatitis or increased severity of illness in HadV-positive compared to negative cases. CONCLUSIONS: Our results highlight an increase in AHUA in adults coinciding with the period of the outbreak in children, but not linked to documented HAdV infection. Tracking changes in routinely collected clinical data through EHR could be used to support outbreak surveillance.


Assuntos
Surtos de Doenças , Registros Eletrônicos de Saúde , Humanos , Registros Eletrônicos de Saúde/estatística & dados numéricos , Estudos Retrospectivos , Masculino , Adulto , Feminino , Adolescente , Adulto Jovem , Pessoa de Meia-Idade , Doença Aguda , Criança , Idoso , Inglaterra/epidemiologia , Lactente , Pré-Escolar , Reino Unido/epidemiologia
5.
Emerg Infect Dis ; 29(10): 2024-2031, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37678158

RESUMO

Early detection of increased infections or new variants of SARS-CoV-2 is critical for public health response. To determine whether cycle threshold (Ct) data from PCR tests for SARS-CoV-2 could serve as an early indicator of epidemic growth, we analyzed daily mean Ct values in England, UK, by gene target and used iterative sequential regression to detect break points in mean Ct values (and positive test counts). To monitor the epidemic in England, we continued those analyses in real time. During September 2020-January 2022, a total of 7,611,153 positive SARS-CoV-2 PCR test results with Ct data were reported. Spike (S) gene target (S+/S-)-specific mean Ct values decreased 6-29 days before positive test counts increased, and S-gene Ct values provided early indication of increasing new variants (Delta and Omicron). Our approach was beneficial in the context of the first waves of the COVID-19 pandemic and can be used to support future infectious disease monitoring.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/diagnóstico , COVID-19/epidemiologia , Pandemias , Inglaterra/epidemiologia
6.
BMC Med ; 21(1): 492, 2023 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-38087343

RESUMO

BACKGROUND: Globally, detections of carbapenemase-producing Enterobacterales (CPE) colonisations and infections are increasing. The spread of these highly resistant bacteria poses a serious threat to public health. However, understanding of CPE transmission and evidence on effectiveness of control measures is severely lacking. This paper provides evidence to inform effective admission screening protocols, which could be important in controlling nosocomial CPE transmission. METHODS: CPE transmission within an English hospital setting was simulated with a data-driven individual-based mathematical model. This model was used to evaluate the ability of the 2016 England CPE screening recommendations, and of potential alternative protocols, to identify patients with CPE-colonisation on admission (including those colonised during previous stays or from elsewhere). The model included nosocomial transmission from colonised and infected patients, as well as environmental contamination. Model parameters were estimated using primary data where possible, including estimation of transmission using detailed epidemiological data within a Bayesian framework. Separate models were parameterised to represent hospitals in English areas with low and high CPE risk (based on prevalence). RESULTS: The proportion of truly colonised admissions which met the 2016 screening criteria was 43% in low-prevalence and 54% in high-prevalence areas respectively. Selection of CPE carriers for screening was improved in low-prevalence areas by adding readmission as a screening criterion, which doubled how many colonised admissions were selected. A minority of CPE carriers were confirmed as CPE positive during their hospital stay (10 and 14% in low- and high-prevalence areas); switching to a faster screening test pathway with a single-swab test (rather than three swab regimen) increased the overall positive predictive value with negligible reduction in negative predictive value. CONCLUSIONS: Using a novel within-hospital CPE transmission model, this study assesses CPE admission screening protocols, across the range of CPE prevalence observed in England. It identifies protocol changes-adding readmissions to screening criteria and a single-swab test pathway-which could detect similar numbers of CPE carriers (or twice as many in low CPE prevalence areas), but faster, and hence with lower demand on pre-emptive infection-control resources. Study findings can inform interventions to control this emerging threat, although further work is required to understand within-hospital transmission sources.


Assuntos
Enterobacteriáceas Resistentes a Carbapenêmicos , Infecção Hospitalar , Infecções por Enterobacteriaceae , Humanos , Teorema de Bayes , Infecções por Enterobacteriaceae/diagnóstico , Infecções por Enterobacteriaceae/epidemiologia , Proteínas de Bactérias , Hospitais , Infecção Hospitalar/diagnóstico , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/prevenção & controle
7.
Proc Biol Sci ; 290(2009): 20231284, 2023 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-37848057

RESUMO

The Office for National Statistics Coronavirus (COVID-19) Infection Survey (ONS-CIS) is the largest surveillance study of SARS-CoV-2 positivity in the community, and collected data on the United Kingdom (UK) epidemic from April 2020 until March 2023 before being paused. Here, we report on the epidemiological and evolutionary dynamics of SARS-CoV-2 determined by analysing the sequenced samples collected by the ONS-CIS during this period. We observed a series of sweeps or partial sweeps, with each sweeping lineage having a distinct growth advantage compared to their predecessors, although this was also accompanied by a gradual fall in average viral burdens from June 2021 to March 2023. The sweeps also generated an alternating pattern in which most samples had either S-gene target failure (SGTF) or non-SGTF over time. Evolution was characterized by steadily increasing divergence and diversity within lineages, but with step increases in divergence associated with each sweeping major lineage. This led to a faster overall rate of evolution when measured at the between-lineage level compared to within lineages, and fluctuating levels of diversity. These observations highlight the value of viral sequencing integrated into community surveillance studies to monitor the viral epidemiology and evolution of SARS-CoV-2, and potentially other pathogens.


Assuntos
COVID-19 , Epidemias , Humanos , COVID-19/epidemiologia , SARS-CoV-2 , Reino Unido/epidemiologia , Inquéritos e Questionários
8.
J Biol Chem ; 297(2): 100928, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34274316

RESUMO

B-cell lymphoma 6 (BCL6) is a zinc finger transcriptional repressor possessing a BTB-POZ (BR-C, ttk, and bab for BTB; pox virus and zinc finger for POZ) domain, which is required for homodimerization and association with corepressors. BCL6 has multiple roles in normal immunity, autoimmunity, and some types of lymphoma. Mice bearing disrupted BCL6 loci demonstrate suppressed high-affinity antibody responses to T-dependent antigens. The corepressor binding groove in the BTB-POZ domain is a potential target for small compound-mediated therapy. Several inhibitors targeting this binding groove have been described, but these compounds have limited or absent in vivo activity. Biophysical studies of a novel compound, GSK137, showed an in vitro pIC50 of 8 and a cellular pIC50 of 7.3 for blocking binding of a peptide derived from the corepressor silencing mediator for retinoid or thyroid hormone receptors to the BCL6 BTB-POZ domain. The compound has good solubility (128 µg/ml) and permeability (86 nM/s). GSK137 caused little change in cell viability or proliferation in four BCL6-expressing B-cell lymphoma lines, although there was modest dose-dependent accumulation of G1 phase cells. Pharmacokinetic studies in mice showed a profile compatible with achieving good levels of target engagement. GSK137, administered orally, suppressed immunoglobulin G responses and reduced numbers of germinal centers and germinal center B cells following immunization of mice with the hapten trinitrophenol. Overall, we report a novel small-molecule BCL6 inhibitor with in vivo activity that inhibits the T-dependent antigen immune response.


Assuntos
Proteínas Proto-Oncogênicas c-bcl-6 , Animais , Linfócitos B/metabolismo , Humanos , Camundongos , Transcrição Gênica , Dedos de Zinco
9.
Clin Infect Dis ; 2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-35917440

RESUMO

BACKGROUND: The SARS-CoV-2 Delta variant has been replaced by the highly transmissible Omicron BA.1 variant, and subsequently by Omicron BA.2. It is important to understand how these changes in dominant variants affect reported symptoms, while also accounting for symptoms arising from other co-circulating respiratory viruses. METHODS: In a nationally representative UK community study, the COVID-19 Infection Survey, we investigated symptoms in PCR-positive infection episodes vs. PCR-negative study visits over calendar time, by age and vaccination status, comparing periods when the Delta, Omicron BA.1 and BA.2 variants were dominant. RESULTS: Between October-2020 and April-2022, 120,995 SARS-CoV-2 PCR-positive episodes occurred in 115,886 participants, with 70,683 (58%) reporting symptoms. The comparator comprised 4,766,366 PCR-negative study visits (483,894 participants); 203,422 (4%) reporting symptoms. Symptom reporting in PCR-positives varied over time, with a marked reduction in loss of taste/smell as Omicron BA.1 dominated, maintained with BA.2 (44%/45% 17 October 2021, 16%/13% 2 January 2022, 15%/12% 27 March 2022). Cough, fever, shortness of breath, myalgia, fatigue/weakness and headache also decreased after Omicron BA.1 dominated, but sore throat increased, the latter to a greater degree than concurrent increases in PCR-negatives. Fatigue/weakness increased again after BA.2 dominated, although to a similar degree to concurrent increases in PCR-negatives. Symptoms were consistently more common in adults aged 18-65 years than in children or older adults. CONCLUSIONS: Increases in sore throat (also common in the general community), and a marked reduction in loss of taste/smell, make Omicron harder to detect with symptom-based testing algorithms, with implications for institutional and national testing policies.

10.
Clin Infect Dis ; 75(1): e329-e337, 2022 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-34748629

RESUMO

BACKGROUND: "Classic" symptoms (cough, fever, loss of taste/smell) prompt severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) polymerase chain reaction (PCR) testing in the United Kingdom. Studies have assessed the ability of different symptoms to identify infection, but few have compared symptoms over time (reflecting variants) and by vaccination status. METHODS: Using the COVID-19 Infection Survey, sampling households across the United Kingdom, we compared symptoms in PCR-positives vs PCR-negatives, evaluating sensitivity of combinations of 12 symptoms (percentage symptomatic PCR-positives reporting specific symptoms) and tests per case (TPC) (PCR-positives or PCR-negatives reporting specific symptoms/ PCR-positives reporting specific symptoms). RESULTS: Between April 2020 and August 2021, 27 869 SARS-CoV-2 PCR-positive episodes occurred in 27 692 participants (median 42 years), of whom 13 427 (48%) self-reported symptoms ("symptomatic PCR-positives"). The comparator comprised 3 806 692 test-negative visits (457 215 participants); 130 612 (3%) self-reported symptoms ("symptomatic PCR-negatives"). Symptom reporting in PCR-positives varied by age, sex, and ethnicity, and over time, reflecting changes in prevalence of viral variants, incidental changes (eg, seasonal pathogens (with sore throat increasing in PCR-positives and PCR-negatives from April 2021), schools reopening) and vaccination rollout. After May 2021 when Delta emerged, headache and fever substantially increased in PCR-positives, but not PCR-negatives. Sensitivity of symptom-based detection increased from 74% using "classic" symptoms, to 81% adding fatigue/weakness, and 90% including all 8 additional symptoms. However, this increased TPC from 4.6 to 5.3 to 8.7. CONCLUSIONS: Expanded symptom combinations may provide modest benefits for sensitivity of PCR-based case detection, but this will vary between settings and over time, and increases tests/case. Large-scale changes to targeted PCR-testing approaches require careful evaluation given substantial resource and infrastructure implications.


Assuntos
COVID-19 , SARS-CoV-2 , COVID-19/diagnóstico , COVID-19/epidemiologia , Teste para COVID-19 , Febre/etiologia , Humanos , SARS-CoV-2/genética , Reino Unido/epidemiologia
11.
PLoS Med ; 16(6): e1002833, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31220083

RESUMO

BACKGROUND: Iron is integral to many physiological processes, and variations in its levels, even within the normal range, can have implications for health. The objective of this study was to explore the broad clinical effects of varying iron status. METHODS AND FINDINGS: Genome-wide association study (GWAS) summary data obtained from 48,972 European individuals (55% female) across 19 cohorts in the Genetics of Iron Status Consortium were used to identify 3 genetic variants (rs1800562 and rs1799945 in the hemochromatosis gene [HFE] and rs855791 in the transmembrane protease serine 6 gene [TMPRSS6]) that associate with increased serum iron, ferritin, and transferrin saturation and decreased transferrin levels, thus serving as instruments for systemic iron status. Phenome-wide association study (PheWAS) of these instruments was performed on 424,439 European individuals (54% female) in the UK Biobank who were aged 40-69 years when recruited from 2006 to 2010, with their genetic data linked to Hospital Episode Statistics (HES) from April, 1995 to March, 2016. Two-sample summary data mendelian randomization (MR) analysis was performed to investigate the effect of varying iron status on outcomes across the human phenome. MR-PheWAS analysis for the 3 iron status genetic instruments was performed separately and then pooled by meta-analysis. Correction was made for testing of multiple correlated phenotypes using a 5% false discovery rate (FDR) threshold. Heterogeneity between MR estimates for different instruments was used to indicate possible bias due to effects of the genetic variants through pathways unrelated to iron status. There were 904 distinct phenotypes included in the MR-PheWAS analyses. After correcting for multiple testing, the 3 genetic instruments for systemic iron status demonstrated consistent evidence of a causal effect of higher iron status on decreasing risk of traits related to anemia (iron deficiency anemia: odds ratio [OR] scaled to a standard deviation [SD] increase in genetically determined serum iron levels 0.72, 95% confidence interval [CI] 0.64-0.81, P = 4 × 10-8) and hypercholesterolemia (hypercholesterolemia: OR 0.88, 95% CI 0.83-0.93, P = 2 × 10-5) and increasing risk of traits related to infection of the skin and related structures (cellulitis and abscess of the leg: OR 1.25, 95% CI 1.10-1.42, P = 6 × 10-4). The main limitations of this study relate to possible bias from pleiotropic effects of the considered genetic variants and misclassification of diagnoses in the HES data. Furthermore, this work only investigated participants with European ancestry, and the findings may not be applicable to other ethnic groups. CONCLUSIONS: Our findings offer novel, to our knowledge, insight into previously unreported effects of iron status, highlighting a potential protective effect of higher iron status on hypercholesterolemia and a detrimental role on risk of skin and skin structure infections. Given the modifiable and variable nature of iron status, these findings warrant further investigation.


Assuntos
Estudo de Associação Genômica Ampla/métodos , Ferro/sangue , Análise da Randomização Mendeliana/métodos , Fenótipo , Adulto , Idoso , Biomarcadores/sangue , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
12.
Vox Sang ; 114(4): 340-348, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30838664

RESUMO

BACKGROUND AND OBJECTIVES: Paediatric blood transfusion for severe anaemia in hospitals in sub-Saharan Africa remains common. Yet, reports describing the haematological quality of donor blood or storage duration in routine practice are very limited. Both factors are likely to affect transfusion outcomes. MATERIALS AND METHODS: We undertook three audits examining the distribution of pack types, haematological quality and storage duration of donor blood used in a paediatric clinical trial of blood at four hospitals in Africa (Uganda and Malawi). RESULTS: The overall distribution of whole blood, packed cells (plasma-reduced by centrifugation) and red cell concentrates (RCC) (plasma-reduced by gravity-dependent sedimentation) used in a randomised trial was 40·7% (N = 1215), 22·4% (N = 669) and 36·8% (N = 1099), respectively. The first audit found similar median haematocrits of 57·0% (50·0,74·0), 64·0% (52·0,72·5; P = 0·238 vs. whole blood) and 56·0% (48·0,67·0; P = 0·462) in whole blood, RCC and packed cells, respectively, which resulted from unclear pack labelling by blood transfusion services (BTS). Re-training of the BTS, hospital blood banks and clinical teams led to, in subsequent audits, significant differences in median haematocrit and haemoglobins across the three pack types and values within expected ranges. Median storage duration time was 12 days (IQR: 6, 19) with 18·2% (537/2964) over 21 days in storage. Initially, 9 (2·8%) packs were issued past the recommended duration of storage, dropping to 0·3% (N = 7) in the third audit post-training. CONCLUSION: The study highlights the importance of close interactions and education between BTS and clinical services and the importance of haemovigilance to ensure safe transfusion practice.


Assuntos
Anemia/terapia , Bancos de Sangue/normas , Doadores de Sangue , Transfusão de Sangue/métodos , Controle de Qualidade , Anemia/sangue , Criança , Hematócrito , Hematologia/normas , Hemoglobinas , Hospitais , Humanos , Malaui , Pediatria/métodos , Garantia da Qualidade dos Cuidados de Saúde , Ensaios Clínicos Controlados Aleatórios como Assunto , Refrigeração , Reprodutibilidade dos Testes , Manejo de Espécimes , Uganda
13.
Bioorg Med Chem Lett ; 29(12): 1454-1458, 2019 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-31005442

RESUMO

The connection between Netherton syndrome and overactivation of epidermal/dermal proteases particularly KLK5 has been well established. To treat sufferers of this severe condition we wished to develop a topical KLK5 inhibitor in order to normalise epidermal shedding and reduce the associated inflammation and itching. In this paper we describe structure-based optimisation of a series of brightly coloured weak KLK5 inhibitors into colourless, non-irritant molecules with good KLK5 activity and selectivity over a range of serine proteases.


Assuntos
Desenho de Fármacos , Calicreínas/antagonistas & inibidores , Síndrome de Netherton/tratamento farmacológico , Humanos
14.
Bioorg Med Chem Lett ; 29(6): 821-825, 2019 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-30691925

RESUMO

Netherton syndrome (NS) is a rare and debilitating severe autosomal recessive genetic skin disease with high mortality rates particularly in neonates. NS is caused by loss-of-function SPINK5 mutations leading to unregulated kallikrein 5 (KLK5) and kallikrein 7 (KLK7) activity. Furthermore, KLK5 inhibition has been proposed as a potential therapeutic treatment for NS. Identification of potent and selective KLK5 inhibitors would enable further exploration of the disease biology and could ultimately lead to a treatment for NS. This publication describes how fragmentation of known trypsin-like serine protease (TLSP) inhibitors resulted in the identification of a series of phenolic amidine-based KLK5 inhibitors 1. X-ray crystallography was used to find alternatives to the phenol interaction leading to identification of carbonyl analogues such as lactam 13 and benzimidazole 15. These reversible inhibitors, with selectivity over KLK1 (10-100 fold), provided novel starting points for the guided growth towards suitable tool molecules for the exploration of KLK5 biology.


Assuntos
Benzamidinas/química , Calicreínas/antagonistas & inibidores , Inibidores de Serina Proteinase/química , Animais , Benzamidinas/síntese química , Benzamidinas/metabolismo , Domínio Catalítico , Desenho de Fármacos , Calicreínas/metabolismo , Síndrome de Netherton/tratamento farmacológico , Ligação Proteica , Salicilamidas/síntese química , Salicilamidas/química , Salicilamidas/metabolismo , Inibidores de Serina Proteinase/síntese química , Inibidores de Serina Proteinase/metabolismo , Spodoptera/genética
15.
Bioorg Med Chem Lett ; 29(20): 126675, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31521475

RESUMO

The connection between Netherton syndrome and overactivation of epidermal/dermal proteases, particularly Kallikrein 5 (KLK5) has been well established and it is expected that a KLK5 inhibitor would improve the dermal barrier and also reduce the pain and itch that afflict Netherton syndrome patients. One of the challenges of covalent protease inhibitors has been achieving selectivity over closely related targets. In this paper we describe the use of structural insight to design and develop a selective and highly potent reversibly covalent KLK5 inhibitor from an initial weakly binding fragment.


Assuntos
Benzamidinas/química , Calicreínas/antagonistas & inibidores , Síndrome de Netherton/tratamento farmacológico , Inibidores de Serina Proteinase/química , Sequência de Aminoácidos , Benzamidinas/farmacologia , Sítios de Ligação , Avaliação Pré-Clínica de Medicamentos , Humanos , Isomerismo , Modelos Moleculares , Estrutura Molecular , Mutação , Ligação Proteica , Inibidor de Serinopeptidase do Tipo Kazal 5/genética , Inibidores de Serina Proteinase/farmacologia , Relação Estrutura-Atividade
16.
Clin Infect Dis ; 66(suppl_2): S140-S146, 2018 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-29514235

RESUMO

Background: Severely immunocompromised human immunodeficiency virus (HIV)-infected individuals have high mortality shortly after starting antiretroviral therapy (ART). We investigated predictors of early mortality and "late presenter" phenotypes. Methods: The Reduction of EArly MortaLITY (REALITY) trial enrolled ART-naive adults and children ≥5 years of age with CD4 counts <100 cells/µL initiating ART in Uganda, Zimbabwe, Malawi, and Kenya. Baseline predictors of mortality through 48 weeks were identified using Cox regression with backwards elimination (exit P > .1). Results: Among 1711 included participants, 203 (12%) died. Mortality was independently higher with older age; lower CD4 count, albumin, hemoglobin, and grip strength; presence of World Health Organization stage 3/4 weight loss, fever, or vomiting; and problems with mobility or self-care at baseline (all P < .04). Receiving enhanced antimicrobial prophylaxis independently reduced mortality (P = .02). Of five late-presenter phenotypes, Group 1 (n = 355) had highest mortality (25%; median CD4 count, 28 cells/µL), with high symptom burden, weight loss, poor mobility, and low albumin and hemoglobin. Group 2 (n = 394; 11% mortality; 43 cells/µL) also had weight loss, with high white cell, platelet, and neutrophil counts suggesting underlying inflammation/infection. Group 3 (n = 218; 10% mortality) had low CD4 counts (27 cells/µL), but low symptom burden and maintained fat mass. The remaining groups had 4%-6% mortality. Conclusions: Clinical and laboratory features identified groups with highest mortality following ART initiation. A screening tool could identify patients with low CD4 counts for prioritizing same-day ART initiation, enhanced prophylaxis, and intensive follow-up. Clinical Trials Registration: ISRCTN43622374.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/tratamento farmacológico , Infecções Oportunistas Relacionadas com a AIDS/mortalidade , Terapia Antirretroviral de Alta Atividade/estatística & dados numéricos , Infecções por HIV/tratamento farmacológico , Infecções por HIV/mortalidade , Adolescente , Adulto , África Subsaariana/epidemiologia , Fatores Etários , Fármacos Anti-HIV/uso terapêutico , Contagem de Linfócito CD4/estatística & dados numéricos , Criança , Pré-Escolar , Feminino , HIV , Humanos , Hospedeiro Imunocomprometido , Masculino , Fenótipo , Medição de Risco , Fatores de Risco
17.
Arterioscler Thromb Vasc Biol ; 37(9): 1788-1792, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28684612

RESUMO

OBJECTIVE: Iron status is a modifiable trait that has been implicated in cardiovascular disease. This study uses the Mendelian randomization technique to investigate whether there is any causal effect of iron status on risk of coronary artery disease (CAD). APPROACH AND RESULTS: A 2-sample Mendelian randomization approach is used to estimate the effect of iron status on CAD risk. Three loci (rs1800562 and rs1799945 in the HFE gene and rs855791 in TMPRSS6) that are each associated with serum iron, transferrin saturation, ferritin, and transferrin in a pattern suggestive of an association with systemic iron status are used as instruments. SNP (single-nucleotide polymorphism)-iron status association estimates are based on a genome-wide association study meta-analysis of 48 972 individuals. SNP-CAD estimates are derived by combining the results of a genome-wide association study meta-analysis of 60 801 CAD cases and 123 504 controls with those of a meta-analysis of 63 746 CAD cases and 130 681 controls obtained from Metabochip and genome-wide association studies. Combined Mendelian randomization estimates are obtained for each marker by pooling results across the 3 instruments. We find evidence of a protective effect of higher iron status on CAD risk (iron odds ratio, 0.94 per SD unit increase; 95% confidence interval, 0.88-1.00; P=0.039; transferrin saturation odds ratio, 0.95 per SD unit increase; 95% confidence interval, 0.91-0.99; P=0.027; log-transformed ferritin odds ratio, 0.85 per SD unit increase; 95% confidence interval, 0.73-0.98; P=0.024; and transferrin odds ratio, 1.08 per SD unit increase; 95% confidence interval, 1.01-1.16; P=0.034). CONCLUSIONS: This Mendelian randomization study supports the hypothesis that higher iron status reduces CAD risk. These findings may highlight a therapeutic target.


Assuntos
Doença da Artéria Coronariana/genética , Proteína da Hemocromatose/genética , Distúrbios do Metabolismo do Ferro/genética , Ferro/sangue , Proteínas de Membrana/genética , Polimorfismo de Nucleotídeo Único , Serina Endopeptidases/genética , Estudos de Casos e Controles , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/prevenção & controle , Bases de Dados Genéticas , Ferritinas/sangue , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Distúrbios do Metabolismo do Ferro/sangue , Distúrbios do Metabolismo do Ferro/diagnóstico , Análise da Randomização Mendeliana , Razão de Chances , Fenótipo , Fatores de Proteção , Medição de Risco , Fatores de Risco , Transferrina/análise
18.
Br J Clin Pharmacol ; 83(10): 2179-2194, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28449232

RESUMO

AIM: Selective androgen receptor modulators (SARMs) induce anabolic effects on muscle without the adverse effects of androgenic steroids. In this first-in-human study, we report the safety, tolerability, pharmacokinetics (PK) and pharmacodynamics of the SARM GSK2881078. METHODS: In Part A, healthy young men (n = 10) received a single dose of study drug (0 mg, 0.05 mg, 0.1 mg, 0.2 mg GSK2881078 or matching-placebo). In Part B, repeat-dose cohorts in men (n = 65) were 0.05 mg, 0.2 mg then 0.08 mg, 0.24 mg, 0.48 mg, 0.75 mg, or placebo; in women (n = 24) they were 0.24 mg, 0.35 mg, or placebo (7 days for 0.5 mg, 14 days for other doses). RESULTS: PK analysis showed dose-proportional increases in exposure and a long >100-h half-life. No significant effects on vital signs, electrocardiograms, cardiac telemetry or standard clinical laboratory studies were observed. A dose-response effect was observed on lowering both high-density lipoprotein and sex hormone-binding globulin. In females at 0.35 mg, differences from placebo were -0.518 (95% confidence interval: -0.703, -0.334) mmol l-1 and -39.1 (-48.5, -29.7) nmol l-1 , respectively. Women showed greater sensitivity to these parameters at lower doses than men. Drug-related adverse events (AEs) were mild. One woman developed a drug rash and was withdrawn. Two men had elevated creatine phosphokinase after physical exertion during follow-up. A serious AE occurred in a subject on placebo. CONCLUSIONS: These data demonstrate pharmacodynamic effects with acceptable tolerability and support further clinical evaluation of this SARM.


Assuntos
Anabolizantes/farmacologia , Indóis/farmacologia , Força Muscular/efeitos dos fármacos , Receptores Androgênicos/metabolismo , Administração Oral , Adulto , Idoso , Anabolizantes/efeitos adversos , Anabolizantes/farmacocinética , Estudos Cross-Over , Relação Dose-Resposta a Droga , Método Duplo-Cego , Eletrocardiografia , Feminino , Meia-Vida , Voluntários Saudáveis , Coração/efeitos dos fármacos , Humanos , Indóis/efeitos adversos , Indóis/farmacocinética , Lipoproteínas HDL/sangue , Masculino , Pessoa de Meia-Idade , Placebos , Pós-Menopausa , Fatores Sexuais , Globulina de Ligação a Hormônio Sexual/análise , Adulto Jovem
20.
J Behav Med ; 39(6): 1020-1032, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27696127

RESUMO

Using dyadic data from 117 married couples in which one partner was diagnosed with Type 2 diabetes, the purpose of this study was to determine whether a number of specific patient and spouse stressors (chronic life stress, diabetes-specific stress, and physical health stress in the form of the number of comorbidities) were associated with Type 2 diabetes patients' dietary and exercise adherence through two potentially modifiable patient and spouse factors-depression symptoms and diabetes self-efficacy. We found that patient and spouse stressors, particularly patient and spouse diabetes stress and the number of patient comorbidities, were related to patient dietary and exercise adherence through patient depression symptoms and both patient and spouse diabetes self-efficacy. These conclusions were strengthened by incorporating a number of relevant control variables in our models and by testing four alternative models which supported our proposed model. These results are important because they provide further evidence of the significant role spouses' play in managing diabetes and they provide diabetes educators and clinicians with specific targets for intervention programming.


Assuntos
Depressão/psicologia , Diabetes Mellitus Tipo 2/psicologia , Modelos Psicológicos , Cooperação do Paciente/psicologia , Cônjuges/psicologia , Adulto , Depressão/complicações , Diabetes Mellitus Tipo 2/complicações , Dieta , Exercício Físico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Autoeficácia , Estresse Psicológico/complicações , Estresse Psicológico/psicologia
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