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1.
Genet Epidemiol ; 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38634654

RESUMO

Nonsyndromic orofacial clefts (NSOFCs) represent a large proportion (70%-80%) of all OFCs. They can be broadly categorized into nonsyndromic cleft lip with or without cleft palate (NSCL/P) and nonsyndromic cleft palate only (NSCPO). Although NSCL/P and NSCPO are considered etiologically distinct, recent evidence suggests the presence of shared genetic risks. Thus, we investigated the genetic overlap between NSCL/P and NSCPO using African genome-wide association study (GWAS) data on NSOFCs. These data consist of 814 NSCL/P, 205 NSCPO cases, and 2159 unrelated controls. We generated common single-nucleotide variants (SNVs) association summary statistics separately for each phenotype (NSCL/P and NSCPO) under an additive genetic model. Subsequently, we employed the pleiotropic analysis under the composite null (PLACO) method to test for genetic overlap. Our analysis identified two loci with genome-wide significance (rs181737795 [p = 2.58E-08] and rs2221169 [p = 4.5E-08]) and one locus with marginal significance (rs187523265 [p = 5.22E-08]). Using mouse transcriptomics data and information from genetic phenotype databases, we identified MDN1, MAP3k7, KMT2A, ARCN1, and VADC2 as top candidate genes for the associated SNVs. These findings enhance our understanding of genetic variants associated with NSOFCs and identify potential candidate genes for further exploration.

2.
BMC Public Health ; 24(1): 507, 2024 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-38365612

RESUMO

BACKGROUND: A fundamental ethical issue in African genomics research is how socio-cultural factors impact perspectives, acceptance, and utility of genomic information, especially in stigmatizing conditions like orofacial clefts (OFCs). Previous research has shown that gatekeepers (e.g., religious, political, family or community leaders) wield considerable influence on the decision-making capabilities of their members, including health issues. Thus, their perspectives can inform the design of engagement strategies and increase exposure to the benefits of genomics testing/research. This is especially important for Africans underrepresented in genomic research. Our study aims to investigate the perspectives of gatekeepers concerning genomic risk information (GRI) in the presence of OFCs in a sub-Saharan African cohort. METHODS: Twenty-five focus group discussions (FGDs) consisting of 214 gatekeepers (religious, community, ethnic leaders, and traditional birth attendants) in Lagos, Nigeria, explored the opinions of participants on genomic risk information (GRI), OFC experience, and the possibility of involvement in collaborative decision-making in Lagos, Nigeria. Transcripts generated from audio recordings were coded and analyzed in NVivo using thematic analysis. RESULTS: Three main themes-knowledge, beliefs, and willingness to act-emerged from exploring the perspective of gatekeepers about GRI in this group. We observed mixed opinions regarding the acceptance of GRI. Many participants believed their role is to guide and support members when they receive results; this is based on the level of trust their members have in them. However, participants felt they would need to be trained by medical experts to do this. Also, religious and cultural beliefs were crucial to determining participants' understanding of OFCs and the acceptance and utilization of GRI. CONCLUSIONS: Incorporating cultural sensitivity into public engagement could help develop appropriate strategies to manage conflicting ideologies surrounding genomic information in African communities. This will allow for more widespread access to the advances in genomics research in underrepresented populations. We also recommend a synergistic relationship between community health specialists/scientists, and community leaders, including spiritual providers to better understand and utilize GRI.


Assuntos
Fenda Labial , Fissura Palatina , Humanos , Nigéria , Grupos Focais , Genômica , Pesquisa Qualitativa
3.
Oral Dis ; 28(7): 1921-1935, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34061439

RESUMO

OBJECTIVES: Cleft lip with/without cleft palate and cleft palate only is congenital birth defects where the upper lip and/or palate fail to fuse properly during embryonic facial development. Affecting ~1.2/1000 live births worldwide, these orofacial clefts impose significant social and financial burdens on affected individuals and their families. Orofacial clefts have a complex etiology resulting from genetic variants combined with environmental covariates. Recent genome-wide association studies and whole-exome sequencing for orofacial clefts identified significant genetic associations and variants in several genes. Of these, we investigated the role of common/rare variants in SHH, RORA, MRPL53, ACVR1, and GDF11. MATERIALS AND METHODS: We sequenced these five genes in 1255 multi-ethnic cleft lip with/without palate and cleft palate only samples in order to find variants that may provide potential explanations for the missing heritability of orofacial clefts. Rare and novel variants were further analyzed using in silico predictive tools. RESULTS: Ninteen total variants of interest were found, with variant types including stop-gain, missense, synonymous, intronic, and splice-site variants. Of these, 3 novel missense variants were found, one in SHH, one in RORA, and one in GDF11. CONCLUSION: This study provides evidence that variants in SHH, RORA, MRPL53, ACVR1, and GDF11 may contribute to risk of orofacial clefts in various populations.


Assuntos
Fenda Labial , Fissura Palatina , Proteínas Morfogenéticas Ósseas , Fenda Labial/genética , Fissura Palatina/genética , Estudo de Associação Genômica Ampla , Fatores de Diferenciação de Crescimento/genética , Humanos
4.
Cleft Palate Craniofac J ; 59(9): 1125-1130, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-34459660

RESUMO

OBJECTIVE: The etiology of cleft palate (CP) is poorly understood compared with that of cleft lip with or without palate (CL ± P). Recently, variants in Grainyhead like transcription factor 3 (GRHL3) were reported to be associated with a risk for CP in European and some African populations including Nigeria, Ghana, and Ethiopia. In order to identify genetic variants that may further explain the etiology of CP, we sequenced GRHL3 in a South African population to determine if rare variants in GRHL3 are associated with the presence of syndromic or nonsyndromic CP. DESIGN: We sequenced the exons of GRHL3 in 100 cases and where possible, we sequenced the parents of the individuals to determine the segregation pattern and presence of de novo variants. SETTING: The cleft clinics from 2 public, tertiary hospitals in Durban, South Africa (SA), namely Inkosi Albert Luthuli Central Hospital and KwaZulu-Natal Children's Hospital. PATIENTS, PARTICIPANTS: One hundred patients with CL ± P and their parents. INTERVENTIONS: Saliva samples were collected. MAIN OUTCOME MEASURES: To ascertain the genetic variants in the GRHL3 gene in patients with CL ± P in SA. RESULTS: Five variants in GRHL3 were observed; 3 were novel and 2 were known variants. The novel variants were intronic variants (c.1062 + 77A>G and c.627 + 1G>A) and missense variant (p.Asp169Gly). CONCLUSIONS: This study provides further evidence that variants in GRHL3 contribute to the risk of nonsyndromic CP in African populations, specifically, in the South African population.


Assuntos
Fenda Labial , Fissura Palatina , Criança , Fenda Labial/genética , Fissura Palatina/genética , Proteínas de Ligação a DNA/genética , Humanos , Polimorfismo de Nucleotídeo Único , África do Sul , Fatores de Transcrição/genética
5.
Cleft Palate Craniofac J ; 59(7): 841-851, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-34382870

RESUMO

OBJECTIVE: Nonsyndromic cleft lip and/or cleft palate (NSCL/P) have multifactorial etiology where genetic factors, gene-environment interactions, stochastic factors, gene-gene interactions, and parent-of-origin effects (POEs) play cardinal roles. POEs arise when the parental origin of alleles differentially impacts the phenotype of the offspring. The aim of this study was to identify POEs that can increase risk for NSCL/P in humans using a genome-wide dataset. METHODS: The samples (174 case-parent trios from Ghana, Ethiopia, and Nigeria) included in this study were from the African only genome wide association studies (GWAS) that was published in 2019. Genotyping of individual DNA using over 2 million multiethnic and African ancestry-specific single-nucleotide polymorphisms from the Illumina Multi-Ethnic Genotyping Array v2 15070954 A2 (genome build GRCh37/hg19) was done at the Center for Inherited Diseases Research. After quality control checks, PLINK was employed to carry out POE analysis employing the pooled subphenotypes of NSCL/P. RESULTS: We observed possible hints of POEs at a cluster of genes at a 1 mega base pair window at the major histocompatibility complex class 1 locus on chromosome 6, as well as at other loci encompassing candidate genes such as ASB18, ANKEF1, AGAP1, GABRD, HHAT, CCT7, DNMT3A, EPHA7, FOXO3, lncRNAs, microRNA, antisense RNAs, ZNRD1, ZFAT, and ZBTB16. CONCLUSION: Findings from our study suggest that some loci may increase the risk for NSCL/P through POEs. Additional studies are required to confirm these suggestive loci in NSCL/P etiology.


Assuntos
Fenda Labial , Fissura Palatina , África Subsaariana , Fenda Labial/genética , Fissura Palatina/genética , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Polimorfismo de Nucleotídeo Único
6.
Cleft Palate Craniofac J ; : 10556656221135926, 2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36384317

RESUMO

Novel or rare damaging mutations have been implicated in the developmental pathogenesis of nonsyndromic cleft lip with or without cleft palate (nsCL ± P). Thus, we investigated the human genome for high-impact mutations that could explain the risk of nsCL ± P in our cohorts.We conducted next-generation sequencing (NGS) analysis of 130 nsCL ± P case-parent African trios to identify pathogenic variants that contribute to the risk of clefting. We replicated this analysis using whole-exome sequence data from a Brazilian nsCL ± P cohort. Computational analyses were then used to predict the mechanism by which these variants could result in increased risks for nsCL ± P.We discovered damaging mutations within the AFDN gene, a cell adhesion molecule (CAMs) that was previously shown to contribute to cleft palate in mice. These mutations include p.Met1164Ile, p.Thr453Asn, p.Pro1638Ala, p.Arg669Gln, p.Ala1717Val, and p.Arg1596His. We also discovered a novel splicing p.Leu1588Leu mutation in this protein. Computational analysis suggests that these amino acid changes affect the interactions with other cleft-associated genes including nectins (PVRL1, PVRL2, PVRL3, and PVRL4) CDH1, CTNNA1, and CTNND1.This is the first report on the contribution of AFDN to the risk for nsCL ± P in humans. AFDN encodes AFADIN, an important CAM that forms calcium-independent complexes with nectins 1 and 4 (encoded by the genes PVRL1 and PVRL4). This discovery shows the power of NGS analysis of multiethnic cleft samples in combination with a computational approach in the understanding of the pathogenesis of nsCL ± P.

7.
Dev Biol ; 458(2): 246-256, 2020 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-31765609

RESUMO

In this study, we investigated the role of the transcription factor Six2 in palate development. Six2 was selected using the SysFACE tool to predict genes from the 2p21 locus, a region associated with clefting in humans by GWAS, that are likely to be involved in palatogenesis. We functionally validated the predicted role of Six2 in palatogenesis by showing that 22% of Six2 null embryos develop cleft palate. Six2 contributes to palatogenesis by promoting mesenchymal cell proliferation and regulating bone formation. The clefting phenotype in Six2-/- embryos is similar to Pax9 null embryos, so we examined the functional relationship of these two genes. Mechanistically, SIX2 binds to a PAX9 5' upstream regulatory element and activates PAX9 expression. In addition, we identified a human SIX2 coding variant (p.Gly264Glu) in a proband with cleft palate. We show this missense mutation affects the stability of the SIX2 protein and leads to decreased PAX9 expression. The low penetrance of clefting in the Six2 null mouse combined with the mutation in one patient with cleft palate underscores the potential combinatorial interactions of other genes in clefting. Our study demonstrates that Six2 interacts with the developmental gene regulatory network in the developing palate.


Assuntos
Proteínas de Homeodomínio/metabolismo , Fator de Transcrição PAX9/genética , Fatores de Transcrição/metabolismo , Animais , Fissura Palatina/embriologia , Fissura Palatina/genética , Anormalidades Craniofaciais/embriologia , Feminino , Regulação da Expressão Gênica no Desenvolvimento/genética , Genes Homeobox , Proteínas de Homeodomínio/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Morfogênese , Proteínas do Tecido Nervoso/metabolismo , Osteogênese , Fator de Transcrição PAX9/metabolismo , Fatores de Transcrição Box Pareados , Palato/metabolismo , Transdução de Sinais/genética , Fatores de Transcrição/genética
8.
Hum Mol Genet ; 28(6): 1038-1051, 2019 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-30452639

RESUMO

Orofacial clefts are common developmental disorders that pose significant clinical, economical and psychological problems. We conducted genome-wide association analyses for cleft palate only (CPO) and cleft lip with or without palate (CL/P) with ~17 million markers in sub-Saharan Africans. After replication and combined analyses, we identified novel loci for CPO at or near genome-wide significance on chromosomes 2 (near CTNNA2) and 19 (near SULT2A1). In situ hybridization of Sult2a1 in mice showed expression of SULT2A1 in mesenchymal cells in palate, palatal rugae and palatal epithelium in the fused palate. The previously reported 8q24 was the most significant locus for CL/P in our study, and we replicated several previously reported loci including PAX7 and VAX1.


Assuntos
População Negra/genética , Fissura Palatina/genética , Genética Populacional , Genoma Humano , Genômica , Locos de Características Quantitativas , Alelos , Animais , Mapeamento Cromossômico , Modelos Animais de Doenças , Elementos Facilitadores Genéticos , Feminino , Expressão Gênica , Frequência do Gene , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Genômica/métodos , Genótipo , Humanos , Masculino , Camundongos , Razão de Chances , Polimorfismo de Nucleotídeo Único
9.
Pharmacol Res ; 163: 105323, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33276099

RESUMO

Ageing is a universal biological phenomenon that is accompanied by the development of chronic, low-grade inflammation and remodelling of the immune system resulting in compromised immune function. In this review, we explore how the trafficking of innate and adaptive immune cells under homeostatic and inflammatory conditions is dysregulated in ageing. We particularly highlight the age-related changes in the expression of adhesion molecules and chemokine receptor/ligands, and the accumulation of senescent cells that drive modulated leukocyte trafficking. These age-related changes to leukocyte trafficking are multifactorial and specific to leukocyte subset, tissue, type of vascular bed, and inflammatory status. However, dysregulated leukocyte trafficking ultimately affects immune responses in older adults. We therefore go on to discuss approved drugs, including anti-integrins, anti-chemokines and statins, as well as novel therapeutics that may be used to target dysregulated leukocyte trafficking in ageing, improve immune responses and delay the onset of age-related diseases.


Assuntos
Envelhecimento/imunologia , Leucócitos/imunologia , Imunidade Adaptativa , Animais , Humanos , Imunidade Inata
10.
BJOG ; 128(9): 1464-1474, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33605016

RESUMO

OBJECTIVE: To compare outcomes before and after implementation of medical abortion (termination of pregnancy) without ultrasound via telemedicine. DESIGN: Cohort analysis. SETTING: The three main abortion providers. POPULATION OR SAMPLE: Medical abortions at home at ≤69 days' gestation in two cohorts: traditional model (in-person with ultrasound, n = 22 158) from January to March 2020 versus telemedicine-hybrid model (either in person or via telemedicine without ultrasound, n = 29 984, of whom 18 435 had no-test telemedicine) between April and June 2020. Sample (n = 52 142) comprises 85% of all medical abortions provided nationally. METHODS: Data from electronic records and incident databases were used to compare outcomes between cohorts, adjusted for baseline differences. MAIN OUTCOME MEASURES: Treatment success, serious adverse events, waiting times, gestation at treatment, acceptability. RESULTS: Mean waiting time from referral to treatment was 4.2 days shorter in the telemedicine-hybrid model and more abortions were provided at ≤6 weeks' gestation (40% versus 25%, P < 0.001). Treatment success (98.8% versus 98.2%, P > 0.999), serious adverse events (0.02% versus 0.04%, P = 0.557) and incidence of ectopic pregnancy (0.2% versus 0.2%, P = 0.796) were not different between models. In the telemedicine-hybrid model, 0.04% were estimated to be over 10 weeks' gestation at the time of the abortion; all were completed safely at home. Within the telemedicine-hybrid model, effectiveness was higher with telemedicine than in-person care (99.2% versus 98.1%, P < 0.001). Acceptability of telemedicine was high (96% satisfied) and 80% reported a future preference for telemedicine. CONCLUSIONS: A telemedicine-hybrid model for medical abortion that includes no-test telemedicine and treatment without an ultrasound is effective, safe, acceptable and improves access to care. TWEETABLE ABSTRACT: Compelling evidence from 52 142 women shows no-test telemedicine abortion is safe, effective and improves care.


Assuntos
Aborto Induzido/métodos , Telemedicina/métodos , Aborto Induzido/estatística & dados numéricos , COVID-19/epidemiologia , Estudos de Casos e Controles , Estudos de Coortes , Inglaterra/epidemiologia , Feminino , Humanos , Pandemias , Gravidez , SARS-CoV-2 , Telemedicina/estatística & dados numéricos , Ultrassonografia Pré-Natal/estatística & dados numéricos
11.
Ultrasound Obstet Gynecol ; 57(1): 43-51, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32388881

RESUMO

OBJECTIVE: To determine the incremental yield of antenatal exome sequencing (ES) over chromosomal microarray analysis (CMA) or conventional karyotyping in prenatally diagnosed congenital heart disease (CHD). METHODS: A prospective cohort study of 197 trios undergoing ES following CMA or karyotyping owing to CHD identified prenatally and a systematic review of the literature were performed. MEDLINE, EMBASE, CINAHL and ClinicalTrials.gov (January 2000 to October 2019) databases were searched electronically for studies reporting on the diagnostic yield of ES in prenatally diagnosed CHD. Selected studies included those with more than three cases, with initiation of testing based upon prenatal phenotype only and that included cases in which CMA or karyotyping was negative. The incremental diagnostic yield of ES was assessed in: (1) all cases of CHD; (2) isolated CHD; (3) CHD associated with extracardiac anomaly (ECA); and (4) CHD according to phenotypic subgroup. RESULTS: In our cohort, ES had an additional diagnostic yield in all CHD, isolated CHD and CHD associated with ECA of 12.7% (25/197), 11.5% (14/122) and 14.7% (11/75), respectively (P = 0.81). The corresponding pooled incremental yields from 18 studies (encompassing 636 CHD cases) included in the systematic review were 21% (95% CI, 15-27%), 11% (95% CI, 7-15%) and 37% (95% CI, 18-56%), respectively. The results did not differ significantly when subanalysis was limited to studies including more than 20 cases, except for CHD associated with ECA, in which the incremental yield was greater (49% (95% CI, 17-80%)). In cases of CHD associated with ECA in the primary analysis, the most common extracardiac anomalies associated with a pathogenic variant were those affecting the genitourinary system (23/52 (44.2%)). The greatest incremental yield was in cardiac shunt lesions (41% (95% CI, 19-63%)), followed by right-sided lesions (26% (95% CI, 9-43%)). In the majority (68/96 (70.8%)) of instances, pathogenic variants occurred de novo and in autosomal dominant (monoallelic) disease genes. The most common (19/96 (19.8%)) monogenic syndrome identified was Kabuki syndrome. CONCLUSIONS: There is an apparent incremental yield of prenatal ES in CHD. While the greatest yield is in CHD associated with ECA, consideration could also be given to performing ES in the presence of an isolated cardiac abnormality. A policy of routine application of ES would require the adoption of robust bioinformatic, clinical and ethical pathways. Copyright © 2020 ISUOG. Published by John Wiley & Sons Ltd.


Assuntos
Sequenciamento do Exoma/métodos , Cardiopatias Congênitas/diagnóstico por imagem , Diagnóstico Pré-Natal/métodos , Feminino , Cardiopatias Congênitas/epidemiologia , Humanos , Cariotipagem , Análise em Microsséries , Gravidez , Estudos Prospectivos
12.
Ultrasound Obstet Gynecol ; 58(4): 509-518, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33847422

RESUMO

OBJECTIVE: To determine the incremental yield of exome sequencing (ES) over chromosomal microarray analysis (CMA) or karyotyping in prenatally diagnosed non-immune hydrops fetalis (NIHF). METHODS: A prospective cohort study (comprising an extended group of the Prenatal Assessment of Genomes and Exomes (PAGE) study) was performed which included 28 cases of prenatally diagnosed NIHF undergoing trio ES following negative CMA or karyotyping. These cases were combined with data from a systematic review of the literature. MEDLINE, EMBASE, CINAHL and ClinicalTrials.gov databases were searched electronically (January 2000 to October 2020) for studies reporting on the incremental yield of ES over CMA or karyotyping in fetuses with prenatally detected NIHF. Inclusion criteria for the systematic review were: (i) at least two cases of NIHF undergoing sequencing; (ii) testing initiated based on prenatal ultrasound-based phenotype; and (iii) negative CMA or karyotyping result. The incremental diagnostic yield of ES was assessed in: (i) all cases of NIHF; (ii) isolated NIHF; (iii) NIHF associated with an additional fetal structural anomaly; and (iv) NIHF according to severity (i.e. two vs three or more cavities affected). RESULTS: In the extended PAGE study cohort, the additional diagnostic yield of ES over CMA or karyotyping was 25.0% (7/28) in all NIHF cases, 21.4% (3/14) in those with isolated NIHF and 28.6% (4/14) in those with non-isolated NIHF. In the meta-analysis, the pooled incremental yield based on 21 studies (306 cases) was 29% (95% CI, 24-34%; P < 0.00001; I2 = 0%) in all NIHF, 21% (95% CI, 13-30%; P < 0.00001; I2 = 0%) in isolated NIHF and 39% (95% CI, 30-49%; P < 0.00001; I2 = 1%) in NIHF associated with an additional fetal structural anomaly. In the latter group, congenital limb contractures were the most prevalent additional structural anomaly associated with a causative pathogenic variant, occurring in 17.3% (19/110) of cases. The incremental yield did not differ significantly according to hydrops severity. The most common genetic disorders identified were RASopathies, occurring in 30.3% (27/89) of cases with a causative pathogenic variant, most frequently due to a PTPN11 variant (44.4%; 12/27). The predominant inheritance pattern in causative pathogenic variants was autosomal dominant in monoallelic disease genes (57.3%; 51/89), with most being de novo (86.3%; 44/51). CONCLUSIONS: Use of prenatal next-generation sequencing in both isolated and non-isolated NIHF should be considered in the development of clinical pathways. Given the wide range of potential syndromic diagnoses and heterogeneity in the prenatal phenotype of NIHF, exome or whole-genome sequencing may prove to be a more appropriate testing approach than a targeted gene panel testing strategy. © 2021 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala/estatística & dados numéricos , Hidropisia Fetal/diagnóstico , Cariotipagem/estatística & dados numéricos , Análise em Microsséries/estatística & dados numéricos , Diagnóstico Pré-Natal/métodos , Feminino , Humanos , Valor Preditivo dos Testes , Gravidez , Estudos Prospectivos , Sequenciamento do Exoma/estatística & dados numéricos
13.
Br J Surg ; 107(4): 391-401, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31502663

RESUMO

BACKGROUND: Circulating cell-free DNA (cfDNA) is not found in healthy subjects, but is readily detected after thermal injury and may contribute to the risk of multiple organ failure. The hypothesis was that a postburn reduction in DNase protein/enzyme activity could contribute to the increase in cfDNA following thermal injury. METHODS: Patients with severe burns covering at least 15 per cent of total body surface area were recruited to a prospective cohort study within 24 h of injury. Blood samples were collected from the day of injury for 12 months. RESULTS: Analysis of blood samples from 64 patients revealed a significant reduction in DNase activity on days 1-28 after injury, compared with healthy controls. DNase protein levels were not affected, suggesting the presence of an enzyme inhibitor. Further analysis revealed that actin (an inhibitor of DNase) was present in serum samples from patients but not those from controls, and concentrations of the actin scavenging proteins gelsolin and vitamin D-binding protein were significantly reduced after burn injury. In a pilot study of ten military patients with polytrauma, administration of blood products resulted in an increase in DNase activity and gelsolin levels. CONCLUSION: The results of this study suggest a novel biological mechanism for the accumulation of cfDNA following thermal injury by which high levels of actin released by damaged tissue cause a reduction in DNase activity. Restoration of the actin scavenging system could therefore restore DNase activity, and reduce the risk of cfDNA-induced host tissue damage and thrombosis.


ANTECEDENTES: El ADN libre de las células circulantes (circulating cell-free DNA, cfDNA) no se encuentra en sujetos sanos, pero se detecta fácilmente después de una lesión térmica y puede contribuir al riesgo de fallo multiorgánico. La hipótesis fue que una disminución en la actividad de la proteína/enzima ADNasa tras la lesión térmica podría contribuir a la elevación del cfDNA que ocurre tras la misma. MÉTODOS: Los pacientes con quemaduras graves con una extensión ≥ 15% del área de superficie corporal total (total body surface area, TBSA) se incluyeron en un estudio prospectivo de cohortes durante las primeras 24 horas posteriores a la lesión. Se recogieron muestras de sangre desde el día de la lesión hasta los 12 meses posteriores a la misma. RESULTADOS: El análisis de muestras de sangre de 64 pacientes reveló una reducción significativa de la actividad de la ADNasa en los días 1 a 28 después de la lesión, en comparación con los controles sanos. Los niveles de proteína ADNasa no se vieron afectados, lo que sugiere la presencia de un inhibidor enzimático. Un análisis adicional reveló que la actina (un inhibidor de la ADNasa) estaba presente en las muestras de suero de los pacientes, pero no en los controles, y las concentraciones de la gelsolina, proteína que causa la disociación de la actina, y la proteína de unión a la vitamina D se redujeron significativamente después de la lesión térmica. En un estudio piloto de 10 pacientes con politrauma por lesiones militares, la administración de hemoderivados produjo un aumento en la actividad de la ADNasa y de los niveles de gelsolina. CONCLUSIÓN: Este estudio sugiere un nuevo mecanismo biológico para la acumulación de cfDNA después de una lesión térmica, por el cual los altos niveles de actina liberada por el tejido dañado causarían una reducción en la actividad de la ADNasa. La restauración del sistema eliminador de actina podría, por lo tanto, restaurar la actividad de la ADNasa y reducir el riesgo de daño tisular y trombosis en el huésped inducido por el cfDNA.


Assuntos
Actinas/metabolismo , Queimaduras/metabolismo , Desoxirribonucleases/metabolismo , Actinas/sangue , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Queimaduras/sangue , Queimaduras/enzimologia , Estudos de Casos e Controles , Ácidos Nucleicos Livres/sangue , Ácidos Nucleicos Livres/metabolismo , Desoxirribonucleases/sangue , Feminino , Fluorometria/métodos , Gelsolina/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Proteína de Ligação a Vitamina D/sangue , Adulto Jovem
14.
Nat Mater ; 16(4): 467-473, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27941808

RESUMO

Photochemical reactions are essential to a large number of important industrial and biological processes. A method for monitoring photochemical reaction kinetics and the dynamics of molecular excitations with spatial resolution within the active molecule would allow a rigorous exploration of the pathway and mechanism of photophysical and photochemical processes. Here we demonstrate that laser-excited muon pump-probe spin spectroscopy (photo-µSR) can temporally and spatially map these processes with a spatial resolution at the single-carbon level in a molecule with a pentacene backbone. The observed time-dependent light-induced changes of an avoided level crossing resonance demonstrate that the photochemical reactivity of a specific carbon atom is modified as a result of the presence of the excited state wavefunction. This demonstrates the sensitivity and potential of this technique in probing molecular excitations and photochemistry.

16.
Osteoporos Int ; 29(7): 1581-1589, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29808230

RESUMO

Among 365 Hertfordshire Cohort Study participants (aged 59-71 years at baseline), higher adiponectin and adiponectin to leptin ratios were associated with lower baseline lumbar spine and femoral neck bone mineral density (BMD). Lower IL-10 was associated with accelerated decline in lumbar spine BMD. This suggests that bone health can be influenced by changes in immune phenotype and alterations in adipokine homeostasis. INTRODUCTION: The aim of this study was to examine the association between indices of inflammation and BMD in a population-based cohort of older adults in the UK. METHODS: Analyses were based on a sample of 194 men and 171 women of the Hertfordshire Cohort Study (community-living, older adults). Dual energy X-ray absorptiometry (DXA) was performed at the lumbar spine and proximal femur at baseline and repeated at a median of 4.5 years (inter-quartile range 3.6 to 5.2). Inflammatory markers (CRP, TNF, IL-1ß, IL-6, IL-8, IL-10, adiponectin and leptin) were ascertained at baseline using enzyme-linked immunosorbent assay (ELISA) techniques and Bio-Plex Pro Assays. Gender-adjusted linear regression was used to examine the associations between markers of inflammation and outcomes with and without adjustment for anthropometric and lifestyle factors. RESULTS: The mean (SD) ages at baseline were 64.4 (2.5) and 66.5 (2.7) years for men and women respectively. Higher levels of adiponectin and adiponectin to leptin ratios were each associated with lower baseline lumbar spine and femoral neck BMD in gender-adjusted (p < 0.01) and fully adjusted (p < 0.05) analyses. Lower levels of IL-10 and TNF were each associated with accelerated decline in lumbar spine BMD in both gender-adjusted (p ≤ 0.05) and fully adjusted (p < 0.05) analyses. CONCLUSIONS: In a cohort of older adults, high levels of adiponectin and adiponectin to leptin ratios were both associated with lower BMD at the lumbar spine and femoral neck at baseline, and lower IL-10 was associated with accelerated decline in BMD at the lumbar spine. This adds weight to the theory that bone health can be influenced by changes in immune phenotype and alterations in adipokine homeostasis.


Assuntos
Densidade Óssea/fisiologia , Mediadores da Inflamação/sangue , Inflamação/fisiopatologia , Absorciometria de Fóton , Adiponectina/sangue , Idoso , Antropometria/métodos , Biomarcadores/sangue , Estudos de Coortes , Feminino , Colo do Fêmur/fisiopatologia , Humanos , Inflamação/sangue , Interleucina-10/sangue , Leptina/sangue , Vértebras Lombares/fisiopatologia , Masculino , Pessoa de Meia-Idade
17.
Calcif Tissue Int ; 102(3): 287-295, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29101476

RESUMO

We investigated the longitudinal relationships between inflammation markers and the following outcomes in a UK cohort study: appendicular lean mass (ALM); walking speed; level and change in grip strength; and sarcopenia defined by the European Working Group on Sarcopenia in Older People. Analyses were based on 336 community-dwelling older men and women (aged 59-70 years) who participated in the Hertfordshire Cohort Study (HCS). Inflammation markers were ascertained at baseline using enzyme-linked immunosorbent assay techniques and Bio-Plex Pro Assays. Grip strength was measured at baseline and follow-up [median follow-up time: 10.8 years (inter-quartile range 10.2-11.6)] and change in grip strength was ascertained using a residual change approach. At follow-up, ALM was ascertained using dual-energy X-ray absorptiometry, customary walking speed was measured and sarcopenia status was ascertained. Gender-adjusted linear and Poisson regression was used to examine the associations between inflammation markers and outcomes with and without adjustment for anthropometric and lifestyle factors. Higher C-reactive protein was associated (p < 0.04) with lower grip strength and accelerated decline in grip strength from baseline to follow-up. Higher cortisol was associated with lower ALM (p < 0.05). Higher interleukin-8 (IL-8) was associated with lower ALM (p < 0.05) and increased risk of sarcopenia [fully-adjusted relative risk per SD increase in IL-8: 1.37 (95% CI 1.10, 1.71), p = 0.005]. All associations were robust in fully-adjusted analyses. Inflammation markers were associated with measures of muscle mass, strength and function in HCS. Further work is required to replicate these associations and to delineate the underlying mechanisms.


Assuntos
Força da Mão/fisiologia , Inflamação/metabolismo , Força Muscular/fisiologia , Sarcopenia/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/metabolismo , Composição Corporal/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/metabolismo , Músculo Esquelético/fisiopatologia
18.
Philos Trans A Math Phys Eng Sci ; 377(2137)2018 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-30530540

RESUMO

For the last 30 years, muon experiments at ISIS pulsed neutron and muon facility at the Rutherford Appleton Laboratory, Oxfordshire have been making a significant contribution to a number of scientific fields. The muon facilities at ISIS consist of eight experimental areas. The European Commission Muon facility consists of three experimental areas with a fixed momentum (28 MeV c-1). The RIKEN-RAL facility has a variable momentum (17-90 MeV c-1) and a choice of negative or positive muons delivering muons to four experimental areas. There is also an area recently used for a muon ionization cooling experiment. In this paper, the ISIS pulsed muon facilities are reviewed, including the beam characteristics that could be useful for muography experiments.This article is part of the Theo Murphy meeting issue 'Cosmic-ray muography'.

19.
Scand J Med Sci Sports ; 28(6): 1653-1660, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29427511

RESUMO

Sedentary time (ST) and moderate-to-vigorous physical activity (MVPA) are associated with cardiometabolic health. Cardiorespiratory fitness (CRF) is also implicated but often overlooked in health recommendations. This study assessed the relationships between ST, MVPA, CRF, and cardiometabolic health in highly active older individuals. 125 healthy amateur cyclists aged 55 to 79 years had their ST and MVPA levels assessed by actigraphy over a 7-day period. CRF was assessed using a maximal effort cycle ergometry test to determine VO2max with results normalized to both body mass and fat-free mass measured by DXA. Markers of cardiometabolic risk (blood glucose, triglycerides, cholesterol, HDL, LDL, Insulin, HOMA IR, blood pressure, and body fat) were assessed and used to determine cumulative cardiometabolic risk. Multiple linear regression was used to assess ST, MVPA, and CRF associations with cardiometabolic health with the relationship between activity levels and CRF determined. CRF was associated with training volume (P = .003), but not ST or MVPA. A high CRF was associated with lower cumulative cardiometabolic risk, body fat percentage, triglyceride, and HDL levels (P < .05 in all cases). MVPA was negatively associated with body fat percentage, while ST was not associated with any marker of cardiometabolic risk when adjusting for activity levels. An association between CRF and cardiometabolic risk even in a group of older individuals with high fitness levels highlights the importance that CRF may have in maintaining health.


Assuntos
Aptidão Cardiorrespiratória , Doenças Cardiovasculares/epidemiologia , Exercício Físico , Síndrome Metabólica/epidemiologia , Actigrafia , Idoso , Atletas , Biomarcadores/sangue , Glicemia , Pressão Sanguínea , Composição Corporal , HDL-Colesterol/sangue , Feminino , Humanos , Insulina/sangue , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Comportamento Sedentário , Triglicerídeos/sangue
20.
Int J Obes (Lond) ; 41(1): 102-111, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27569681

RESUMO

BACKGROUND/OBJECTIVES: The purpose of this study was to determine whether circulating pro-inflammatory cytokines, elevated with increased fat mass and ageing, were associated with muscle properties in young and older people with variable adiposity. SUBJECTS/METHODS: Seventy-five young (18-49 yrs) and 67 older (50-80 yrs) healthy, untrained men and women (BMI: 17-49 kg/m2) performed isometric and isokinetic plantar flexor maximum voluntary contractions (MVCs). Volume (Vm), fascicle pennation angle (FPA), and physiological cross-sectional area (PCSA) of the gastrocnemius medialis (GM) muscle were measured using ultrasonography. Voluntary muscle activation (VA) was assessed using electrical stimulation. GM specific force was calculated as GM fascicle force/PCSA. Percentage body fat (BF%), body fat mass (BFM), and lean mass (BLM) were assessed using dual-energy X-ray absorptiometry. Serum concentration of 12 cytokines was measured using multiplex luminometry. RESULTS: Despite greater Vm, FPA, and PCSA (P<0.05), young individuals with BF% ⩾40 exhibited 37% less GM specific force compared to young BF%<40 (P<0.05). Older adults with BF% ⩾40 showed greater isokinetic MVC compared to older BF%<40 (P=0.019) but this was reversed when normalised to body mass (P<0.001). IL-6 correlated inversely with VA in young (r=-0.376; P=0.022) but not older adults (p>0.05), while IL-8 correlated with VA in older but not young adults (r⩾0.378, P⩽0.027). TNF-alpha correlated with MVC, lean mass, GM FPA and maximum force in older adults (r⩾0.458; P⩽0.048). CONCLUSIONS: The age- and adiposity-dependent relationships found here provide evidence that circulating pro-inflammatory cytokines may play different roles in muscle remodelling according to the age and adiposity of the individual.


Assuntos
Adiposidade/fisiologia , Envelhecimento/fisiologia , Inflamação/fisiopatologia , Músculo Esquelético/patologia , Músculo Esquelético/fisiopatologia , Obesidade/fisiopatologia , Absorciometria de Fóton , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/metabolismo , Fenômenos Biomecânicos , Citocinas/metabolismo , Feminino , Humanos , Inflamação/etiologia , Inflamação/metabolismo , Contração Isométrica , Masculino , Pessoa de Meia-Idade , Força Muscular/fisiologia , Dinamômetro de Força Muscular , Obesidade/complicações , Obesidade/metabolismo , Reprodutibilidade dos Testes , Adulto Jovem
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