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1.
J Crohns Colitis ; 18(3): 446-461, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37748021

RESUMO

BACKGROUND AND AIMS: Inflammatory bowel diseases (IBD) are characterized by mucosal inflammation and sequential fibrosis formation, but the exact role of the hyperactive NLRP3 inflammasome in these processes is unclear. Thus, we studied the expression and function of the NLRP3 inflammasome in the context of inflammation and fibrosis in IBD. METHODS: We analysed intestinal NLRP3 expression in mucosal immune cells and fibroblasts from IBD patients and NLRP3-associated gene expression via single-cell RNA sequencing and microarray analyses. Furthermore, cytokine secretion of NLRP3 inhibitor treated blood and mucosal cells, as well as proliferation, collagen production, and cell death of NLRP3 inhibitor treated intestinal fibroblasts from IBD patients were studied. RESULTS: We found increased NLRP3 expression in the inflamed mucosa of IBD patients and NLRP3 inhibition led to reduced IL-1ß and IL-18 production in blood cells and diminished the bioactive form of mucosal IL-1ß. Single cell analysis identified overlapping expression patterns of NLRP3 and IL-1ß in classically activated intestinal macrophages and we also detected NLRP3 expression in CD163+ macrophages. In addition, NLRP3 expression was also found in intestinal fibroblasts from IBD patients. Inhibition of NLRP3 led to reduced proliferation of intestinal fibroblasts, which was associated with a marked decrease in production of collagen type I and type VI in IBD patients. Moreover, NLRP3 inhibition in intestinal fibroblasts induced autophagy, a cellular process involved in collagen degradation. CONCLUSIONS: In the presented study, we demonstrate that inhibiting NLRP3 might pave the way for novel therapeutic approaches in IBD, especially to prevent the severe complication of intestinal fibrosis formation.


Assuntos
Doenças Inflamatórias Intestinais , Proteína 3 que Contém Domínio de Pirina da Família NLR , Humanos , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Inflamassomos/metabolismo , Mucosa/metabolismo , Interleucina-1beta/metabolismo , Inflamação , Fibroblastos/metabolismo , Colágeno , Fibrose
2.
Pediatrics ; 152(5)2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37800272

RESUMO

BACKGROUND: Reducing child mortality in low-income countries is constrained by a lack of vital statistics. In the absence of such data, verbal autopsies provide an acceptable method to determining attributable causes of death. The objective was to assess potential causes of pediatric postdischarge mortality in children younger than age 5 years (under-5) originally admitted for suspected sepsis using verbal autopsies. METHODS: Secondary analysis of verbal autopsy data from children admitted to 6 hospitals across Uganda from July 2017 to March 2020. Structured verbal autopsy interviews were conducted for all deaths within 6 months after discharge. Two physicians independently classified a primary cause of death, up to 4 alternative causes, and up to 5 contributing conditions using the Start-Up Mortality List, with discordance resolved by consensus. RESULTS: Verbal autopsies were completed for 361 (98.6%) of the 366 (5.9%) children who died among 6191 discharges (median admission age: 5.4 months [interquartile range, 1.8-16.7]; median time to mortality: 28 days [interquartile range, 9-74]). Most deaths (62.3%) occurred in the community. Leading primary causes of death, assigned in 356 (98.6%) of cases, were pneumonia (26.2%), sepsis (22.1%), malaria (8.5%), and diarrhea (7.9%). Common contributors to death were malnutrition (50.5%) and anemia (25.7%). Reviewers were less confident in their causes of death for neonates than older children (P < .05). CONCLUSIONS: Postdischarge mortality frequently occurred in the community in children admitted for suspected sepsis in Uganda. Analyses of the probable causes for these deaths using verbal autopsies suggest potential areas for interventions, focused on early detection of infections, as well as prevention and treatment of underlying contributors such as malnutrition and anemia.


Assuntos
Anemia , Desnutrição , Sepse , Recém-Nascido , Criança , Humanos , Lactente , Adolescente , Pré-Escolar , Autopsia , Causas de Morte , Uganda/epidemiologia , Assistência ao Convalescente , Alta do Paciente , Sepse/diagnóstico , Anemia/diagnóstico
3.
Antiviral Res ; 197: 105211, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34826506

RESUMO

AB-506, a small-molecule inhibitor targeting the HBV core protein, inhibits viral replication in vitro (HepAD38 cells: EC50 of 0.077 µM, CC50 > 25 µM) and in vivo (HBV mouse model: ∼3.0 log10 reductions in serum HBV DNA compared to the vehicle control). Binding of AB-506 to HBV core protein accelerates capsid assembly and inhibits HBV pgRNA encapsidation. Furthermore, AB-506 blocks cccDNA establishment in HBV-infected HepG2-hNTCP-C4 cells and primary human hepatocytes, leading to inhibition of viral RNA, HBsAg, and HBeAg production (EC50 from 0.64 µM to 1.92 µM). AB-506 demonstrated activity across HBV genotypes A-H and maintains antiviral activity against nucleos(t)ide analog-resistant variants in vitro. Evaluation of AB-506 against a panel of core variants showed that T33N/Q substitutions results in >200-fold increase in EC50 values, while L30F, L37Q, and I105T substitutions showed an 8 to 20-fold increase in EC50 values in comparison to the wild-type. In vitro combinations of AB-506 with NAs or an RNAi agent were additive to moderately synergistic. AB-506 exhibits good oral bioavailability, systemic exposure, and higher liver to plasma ratios in rodents, a pharmacokinetic profile supporting clinical development for chronic hepatitis B.


Assuntos
Antivirais/farmacologia , Vírus da Hepatite B/efeitos dos fármacos , Proteínas do Core Viral/antagonistas & inibidores , Replicação Viral/efeitos dos fármacos , Animais , Antivirais/farmacocinética , Células Cultivadas , Avaliação Pré-Clínica de Medicamentos , Feminino , Células Hep G2 , Hepatócitos/efeitos dos fármacos , Hepatócitos/virologia , Humanos , Camundongos , Ratos , Montagem de Vírus/efeitos dos fármacos
4.
Nutrients ; 13(1)2021 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-33466826

RESUMO

Iodine is essential for normal thyroid function, supporting healthy fetal and child development. Iodine requirements increase in pregnancy, but many women in regions without salt iodization have insufficient intakes. We explored associations between iodide intake and urinary iodine concentration (UIC), urinary iodine/creatinine ratio (I/Cr), thyroid stimulating hormone, thyroglobulin, free triiodothyronine, free thyroxine and palpable goiter in a region of mild-to-moderate iodine insufficiency. A total of 246 pregnant women aged 18-40 in Bradford, UK, joined the Health and Iodine in Babies (Hiba) study. They provided detailed information on diet and supplement use, urine and serum samples and were assessed for goiter at around 12, 26 and 36 weeks' gestation, and 6, 18 and 30 weeks postpartum. Dietary iodide intake from food and drink was estimated using six 24 h recalls. During pregnancy, median (IQR) dietary iodide intake was 101 µg/day (54, 142), with 42% from dairy and 9% from white fish. Including supplements, intake was 143 µg/day (94, 196), with 49% < UK reference nutrient intake (140 µg/day). Women with Pakistani heritage had 129 µg/day (87, 190) median total intake. Total intake during pregnancy was associated with 4% (95% CI: 1%, 7%) higher UIC, 5% (3%, 7%) higher I/Cr, 4% (2%, 6%) lower thyroglobulin and 21% (9%, 32%) lower odds of palpable goiter per 50 µg/day. This cohort consumed less iodide in pregnancy than UK and World Health Organization dietary recommendations. UIC, I/Cr and thyroglobulin were associated with intake. Higher intake was associated with fewer goiters. Because dairy was the dominant source of iodide, women following plant-based or low-dairy diets may be at particular risk of iodine insufficiency.


Assuntos
Deficiências Nutricionais , Iodetos/análise , Iodo , Fenômenos Fisiológicos da Nutrição Materna/fisiologia , Hormônios Tireóideos/sangue , Adolescente , Adulto , Deficiências Nutricionais/sangue , Deficiências Nutricionais/epidemiologia , Deficiências Nutricionais/urina , Dieta/estatística & dados numéricos , Suplementos Nutricionais/estatística & dados numéricos , Feminino , Humanos , Iodo/deficiência , Iodo/urina , Período Pós-Parto/fisiologia , Gravidez/estatística & dados numéricos , Reino Unido , Adulto Jovem
5.
Paediatr Perinat Epidemiol ; 35(2): 236-246, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32870514

RESUMO

BACKGROUND: Maternal iodine requirements increase during pregnancy to supply thyroid hormones critical for fetal neurodevelopment. Iodine insufficiency may result in poorer cognitive or child educational outcomes but current evidence is sparse and inconsistent. OBJECTIVES: To quantify the association between maternal iodine status and child educational outcomes. METHODS: Urinary iodine concentrations (UIC) and iodine/creatinine ratios (I:Cr) were measured in 6971 mothers at 26-28 weeks' gestation participating in the Born in Bradford cohort. Maternal iodine status was examined in relation to child school achievement (early years foundation stage (EYFS), phonics, and Key Stage 1 (KS1)), other learning outcomes, social and behavioural difficulties, and sensorimotor control in 5745 children aged 4-7 years. RESULTS: Median (interquartile range) UIC was 76 µg/L (46, 120), and I:Cr was 83 µg/g (59, 121). Overall, there was no strong or consistent evidence to support associations between UIC or I:Cr and neurodevelopmental outcomes. For instance, predicted EYFS and phonics scores (primary outcomes) at the 25th vs 75th I:Cr percentiles (99% confidence intervals) were similar, with no evidence of associations: EYFS scores were 32 (99% CI 31, 33) and 33 (99% CI 32, 34), and phonics scores were 34 (99% CI 33, 35) and 35 (99% CI 34, 36), respectively. CONCLUSIONS: In the largest single study of its kind, there was little evidence of detrimental neurodevelopmental outcomes in children born to pregnant women with iodine insufficiency as defined by World Health Organization-outlined thresholds. Alternative functional biomarkers for iodine status in pregnancy and focused assessment of other health outcomes may provide additional insight.


Assuntos
Iodo , Criança , Cognição , Feminino , Idade Gestacional , Humanos , Estado Nutricional , Gravidez , Gravidez Múltipla , Reino Unido/epidemiologia
6.
BMC Pediatr ; 20(1): 544, 2020 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-33276760

RESUMO

BACKGROUND: Maternal iodine requirements increase during pregnancy to supply thyroid hormones essential for fetal brain development. Maternal iodine deficiency can lead to hypothyroxinemia, a reduced fetal supply of thyroid hormones which, in the first trimester, has been linked to an increased risk of autism spectrum disorder (ASD) in the child. No study to date has explored the direct link between maternal iodine deficiency and diagnosis of ASD in offspring. METHODS: Urinary iodine concentrations (UIC) and iodine/creatinine ratios (I:Cr) were measured in 6955 mothers at 26-28 weeks gestation participating in the Born in Bradford (BiB) cohort. Maternal iodine status was examined in relation to the probability of a Read (CTV3) code for autism being present in a child's primary care records through a series of logistic regression models with restricted cubic splines. RESULTS: Median (inter-quartile range) UIC was 76 µg/L (46, 120) and I:Cr was 83 µg/g (59, 121) indicating a deficient population according to WHO guidelines. Ninety two children (1·3%) in our cohort had received a diagnosis of ASD by the census date. Overall, there was no evidence to support an association between I:Cr or UIC and ASD risk in children aged 8-12 years (p = 0·3). CONCLUSIONS: There was no evidence of an increased clinical ASD risk in children born to mothers with mild-to-moderate iodine deficiency at 26 weeks gestation. Alternative functional biomarkers of exposure and a wider range of conditions may provide further insight.


Assuntos
Transtorno do Espectro Autista , Iodo , Transtorno do Espectro Autista/etiologia , Criança , Feminino , Desenvolvimento Fetal , Idade Gestacional , Humanos , Gravidez , Reino Unido/epidemiologia
7.
Environ Sci Technol ; 54(21): 13439-13447, 2020 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-33064454

RESUMO

Exposure to wildfire smoke causes adverse health outcomes, suggesting the importance of accurately estimating smoke concentrations. Geostatistical methods can combine observed, modeled, and satellite-derived concentrations to produce accurate estimates. Here, we estimate daily average ground-level PM2.5 concentrations at a 1 km resolution during the October 2017 California wildfires, using the Constant Air Quality Model Performance (CAMP) and Bayesian Maximum Entropy (BME) methods to bias-correct and fuse three concentration datasets: permanent and temporary monitoring stations, a chemical transport model (CTM), and satellite-derived estimates. Four BME space/time kriging and data fusion methods were evaluated. All BME methods produce more accurate estimates than the standalone CTM and satellite products. Adding temporary station data increases the R2 by 36%. The data fusion of observations with the CAMP-corrected CTM and satellite-derived concentrations provides the best estimate (R2 = 0.713) in fire-impacted regions, emphasizing the importance of combining multiple datasets. We estimate that approximately 65,000 people were exposed to very unhealthy air (daily average PM2.5 ≥ 150.5 µg/m3).


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Incêndios , Incêndios Florestais , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Teorema de Bayes , California , Entropia , Monitoramento Ambiental , Humanos , Material Particulado/análise , Fumaça/análise
8.
BMC Med ; 18(1): 132, 2020 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-32522280

RESUMO

BACKGROUND: Severe iodine insufficiency in pregnancy has significant consequences, but there is inadequate evidence to indicate what constitutes mild or moderate insufficiency, in terms of observed detrimental effects on pregnancy or birth outcomes. A limited number of studies have examined iodine status and birth outcomes, finding inconsistent evidence for specific outcomes. METHODS: Maternal iodine status was estimated from spot urine samples collected at 26-28 weeks' gestation from 6971 mothers in the Born in Bradford birth cohort. Associations with outcomes were examined for both urinary iodine concentration (UIC) and iodine-to-creatinine ratio (I:Cr). Outcomes assessed included customised birthweight (primary outcome), birthweight, small for gestational age (SGA), low birthweight, head circumference and APGAR score. RESULTS: There was a small positive association between I:Cr and birthweight in adjusted analyses. For a typical participant, the predicted birthweight centile at the 25th percentile of I:Cr (59 µg/g) was 2.7 percentage points lower than that at the 75th percentile of I:Cr (121 µg/g) (99% confidence interval (CI) 0.8 to 4.6), birthweight was predicted to be 41 g lower (99% CI 13 to 69) and the predicted probability of SGA was 1.9 percentage points higher (99% CI 0.0 to 3.7). There was no evidence of associations using UIC or other birth outcomes, including stillbirth, preterm birth, ultrasound growth measures or congenital anomalies. CONCLUSION: Lower maternal iodine status was associated with lower birthweight and greater probability of SGA. Whilst small, the effect size for lower iodine on birthweight is comparable to environmental tobacco smoke exposure. Iodine insufficiency is avoidable, and strategies to avoid deficiency in women of reproductive age should be considered. TRIAL REGISTRATION: ClinicalTrials.gov NCT03552341. Registered on June 11, 2018.


Assuntos
Anormalidades Congênitas/epidemiologia , Retardo do Crescimento Fetal/epidemiologia , Iodo/metabolismo , Mães/estatística & dados numéricos , Resultado da Gravidez/epidemiologia , Adulto , Peso ao Nascer , Feminino , Humanos , Recém-Nascido , Masculino , Gravidez , Reino Unido
9.
Afr J Prim Health Care Fam Med ; 12(1): e1-e7, 2020 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-32242430

RESUMO

BACKGROUND: In 2012, 38% of the South African population resided in the rural areas of the country. The professional healthcare services are concentrated in the urban areas, resulting in an imbalance between urban and rural healthcare services. AIM: The aim of this study was to evaluate the use of a non-governmental organisation (NGO)-supported mobile healthcare service in a remote area. SETTING: Eastern Cape Province in South Africa. METHODS: The walking distance between the community and the nearest fixed government healthcare service was evaluated and compared with the recommendations of World Health Organization (WHO). Services provided to people visiting the mobile community service were recorded, and descriptive data were analysed and compared with the anonymised patient records of the nearest fixed service clinic. RESULTS: Of the 30 outreach points served by the NGO, 24 points were at a distance more than the WHO-designated walking distance and 11 points were more than twice the WHO-designated distance from the perspective of fixed clinic. The average headcount per annum of the outreach NGO mobile clinics exceeded those of the fixed Department of Health (DoH) clinics by an average of 250 patients per clinic session. The increase in services was also noteworthy, with a mean differential of 1774 services per annum for the same day above that of the DoH clinics. CONCLUSION: Mobile services could make a difference to the utilisation of essential healthcare facilities. The provision of augmented NGO-led mobile clinical outreach services and joint government-NGO partnerships holds possibilities for improving healthcare for those living in remote rural areas.


Assuntos
Instituições de Assistência Ambulatorial/estatística & dados numéricos , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Atenção Primária à Saúde/métodos , Serviços de Saúde Rural/estatística & dados numéricos , Humanos , Organizações , Atenção Primária à Saúde/estatística & dados numéricos , População Rural , África do Sul
10.
J Crohns Colitis ; 14(4): 508-524, 2020 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-31630153

RESUMO

BACKGROUND AND AIMS: The topically applied Toll-like receptor 9 [TLR9] agonist cobitolimod is a first-in-class DNA-based oligonucleotide with demonstrated therapeutic efficacy in clinical trials with ulcerative colitis [UC] patients. We here characterized its anti-inflammatory mechanism in UC. METHODS: Luminal cobitolimod administration was evaluated in an experimental dextran sodium sulfate [DSS]-induced colitis model. Cultured blood and mucosal cells from UC patients were treated with cobitolimod and analysed via microarray, quantitative real-time PCR, ELISA and flow cytometry. Intestinal slides of cobitolimod-treated UC patients were analysed by immunohistochemistry. RESULTS: Cobitolimod administration markedly suppressed experimental colitis activity, and microarray analyses demonstrated mucosal IL10 upregulation and suppression of IL17 signalling pathways. Cobitolimod treatment was associated with significant induction of mucosal IL10+Tr1 and Treg cells and suppression of Th17 cells. TLR9 knockout mice indicated that cobitolimod requires TLR9 signalling for IL10 induction. In UC patients, mucosal TLR9 levels correlated with severity of inflammation. Cobitolimod inhibited IL17A and IL17F, but increased IL10 and FoxP3 expression in cultured intestinal UC T cells. Cobitolimod-mediated suppression of intestinal IL17+T cells was abrogated by IL10 blockade. Furthermore, cobitolimod led to heightened IL10 production by wound healing macrophages. Immunohistochemistry in intestinal biopsies of cobitolimod-treated UC patients indicated increased presence of IL10+mononuclear and regulatory T cells, as well as reduction of IL17+cells. CONCLUSION: Activation of TLR9 via cobitolimod might represent a novel therapeutic approach in UC, as it suppresses Th17 cells and induces anti-inflammatory IL10+macrophages and regulatory T cells, thereby modifying the dysregulated intestinal cytokine balance. PODCAST: This article has an associated podcast which can be accessed at https://academic.oup.com/ecco-jcc/pages/podcast.


Assuntos
Colite Ulcerativa , Mucosa Intestinal , Macrófagos , Oligodesoxirribonucleotídeos , Linfócitos T Reguladores , Células Th17 , Receptor Toll-Like 9/agonistas , Animais , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/farmacocinética , Técnicas de Cultura de Células , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/imunologia , Colite Ulcerativa/patologia , Modelos Animais de Doenças , Feminino , Fármacos Gastrointestinais/administração & dosagem , Fármacos Gastrointestinais/farmacocinética , Regulação da Expressão Gênica , Humanos , Imunomodulação , Interleucina-10/análise , Interleucina-17/análise , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/imunologia , Mucosa Intestinal/patologia , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Macrófagos/patologia , Masculino , Camundongos , Pessoa de Meia-Idade , Oligodesoxirribonucleotídeos/administração & dosagem , Oligodesoxirribonucleotídeos/farmacocinética , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/imunologia , Células Th17/efeitos dos fármacos , Células Th17/imunologia , Análise Serial de Tecidos/métodos
11.
Artigo em Inglês | AIM (África) | ID: biblio-1257701

RESUMO

Background: In 2012, 38% of the South African population resided in the rural areas of the country. The professional healthcare services are concentrated in the urban areas, resulting in an imbalance between urban and rural healthcare services. Aim: The aim of this study was to evaluate the use of a non-governmental organisation (NGO)-supported mobile healthcare service in a remote area. Setting: Eastern Cape Province in South Africa. Methods: The walking distance between the community and the nearest fixed government healthcare service was evaluated and compared with the recommendations of World Health Organization (WHO). Services provided to people visiting the mobile community service were recorded, and descriptive data were analysed and compared with the anonymised patient records of the nearest fixed service clinic. Results: Of the 30 outreach points served by the NGO, 24 points were at a distance more than the WHO-designated walking distance and 11 points were more than twice the WHO-designated distance from the perspective of fixed clinic. The average headcount per annum of the outreach NGO mobile clinics exceeded those of the fixed Department of Health (DoH) clinics by an average of 250 patients per clinic session. The increase in services was also noteworthy, with a mean differential of 1774 services per annum for the same day above that of the DoH clinics. Conclusion: Mobile services could make a difference to the utilisation of essential healthcare facilities. The provision of augmented NGO-led mobile clinical outreach services and joint government­NGO partnerships holds possibilities for improving healthcare for those living in remote rural areas


Assuntos
Organizações , Atenção Primária à Saúde , Serviços de Saúde Rural , População Rural , África do Sul , Organização Mundial da Saúde
12.
Sci Rep ; 9(1): 14260, 2019 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-31582787

RESUMO

Parabolic flight maneuvers of Novespace's Airbus A310 ZERO-G produce subsequent phases of hypergravity (about 20 s), microgravity (about 22 s) and another 20 s hypergravity on experiments located in the experiment area of the aircraft. The 29th DLR parabolic flight campaign consisted of four consecutive flight days with thirty-one parabolas each day. Euglena gracilis cells were fixed with TRIzol during different acceleration conditions at the first and the last parabola of each flight. Samples were collected and analyzed with microarrays for one-color gene expression analysis. The data indicate significant changes in gene expression in E. gracilis within short time. Hierarchical clustering shows that changes induced by the different accelerations yield reproducible effects at independent flight days. Transcription differed between the first and last parabolas indicating adaptation effects in the course of the flight. Different gene groups were found to be affected in different phases of the parabolic flight, among others, genes involved in signal transduction, calcium signaling, transport mechanisms, metabolic pathways, and stress-response as well as membrane and cytoskeletal proteins. In addition, transcripts of other areas, e.g., DNA and protein modification, were altered. The study contributes to the understanding of short-term effects of microgravity and different accelerations on cells at a molecular level.


Assuntos
Euglena gracilis/genética , Regulação da Expressão Gênica , Aceleração , Aeronaves , Expressão Gênica , Hipergravidade , Voo Espacial , Simulação de Ausência de Peso
13.
Plant Physiol Biochem ; 139: 411-418, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30981157

RESUMO

Potato tuber dormancy is critical for the postharvest quality. The supply of carbohydrates is considered as one of the important factors controlling the rate of potato tuber sprouting. Starch is the major carbohydrate reserve in potato tuber, but very little is known about the specific starch degrading enzymes responsible for controlling tuber dormancy and sprouting. In this study, we demonstrate that an α-amylase gene StAmy23 is involved in starch breakdown and regulation of tuber dormancy. Silencing of StAmy23 delayed tuber sprouting by one to two weeks compared with the control. This phenotype is accompanied by reduced levels of reducing sugars and elevated levels of malto-oligosaccharides in tuber cortex and pith tissue below the bud eye of StAmy23-deficient potato tubers. Changes in soluble sugars is accompanied by a slight variation of phytoglycogen structure and starch granule size. Our results suggest that StAmy23 may stimulate sprouting by hydrolyzing soluble phytoglycogen to ensure supply of sugars during tuber dormancy.


Assuntos
Germinação/fisiologia , Proteínas de Plantas/metabolismo , Tubérculos/metabolismo , Tubérculos/fisiologia , Solanum tuberosum/metabolismo , Solanum tuberosum/fisiologia , alfa-Amilases/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Germinação/genética , Proteínas de Plantas/genética , Tubérculos/genética , Solanum tuberosum/genética , Amido/metabolismo , Sacarose/metabolismo , Açúcares/metabolismo , alfa-Amilases/genética
14.
PLoS One ; 14(3): e0213455, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30840699

RESUMO

PURPOSE: The sudden death of a child is a catastrophic event for both the family and the healthcare workers involved. Confidential enquiries provide a biomedical depiction of the processes and quality of care delivered and drive improvements in care. However, these rarely include an assessment of the patient/caregiver experience which is increasingly regarded as a key measure of quality of care. METHODS: A parallel convergent mixed methods design was used to compare and contrast medically-assessed clinical quality of care with caregiver perceptions of quality and care in a cohort of sudden childhood deaths in emergency facilities in Cape Town, South Africa. RESULTS: Amongst the 29 sudden childhood deaths, clinical quality of care was assessed as poor in 11 (38%) and the death was considered avoidable or potentially avoidable in 16 (55%). The main themes identified from the caregivers were their perception of the quality of care delivered (driven by perceived healthcare worker effort, empathy and promptness), the way the family was dealt with during the final resuscitation, and communications at the time of and after the death. Ten (35%) caregivers were predominantly negative about the care delivered, of whom four received fair clinical quality of care; 13 (49%) of caregivers had predominantly positive experiences, one of whom received poor clinical quality of care. CONCLUSIONS: Caregivers' experiences of the healthcare service around their child's death are influenced largely by the way healthcare workers communicate with them, as well as the perceived clinical effort. This is not always concordant with the clinically assessed quality of care. Simple interventions such as protocols and education of healthcare workers in dealing with families of a dying or deceased child could improve families' experiences at a time when they are most vulnerable.


Assuntos
Morte Súbita , Instalações de Saúde , Cuidadores/psicologia , Causas de Morte , Criança , Pré-Escolar , Estudos de Coortes , Comunicação , Morte Súbita/etiologia , Atenção à Saúde , Empatia , Família/psicologia , Feminino , Pessoal de Saúde/psicologia , Humanos , Lactente , Recém-Nascido , Masculino , Qualidade da Assistência à Saúde , Ressuscitação , África do Sul
15.
Nutrients ; 11(2)2019 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-30791590

RESUMO

Severe iodine deficiency in mothers is known to impair foetal development. Pregnant women in the UK may be iodine insufficient, but recent assessments of iodine status are limited. This study assessed maternal urinary iodine concentrations (UIC) and birth outcomes in three UK cities. Spot urines were collected from 541 women in London, Manchester and Leeds from 2004⁻2008 as part of the Screening for Pregnancy End points (SCOPE) study. UIC at 15 and 20 weeks' gestation was estimated using inductively coupled plasma-mass spectrometry (ICP-MS). Associations were estimated between iodine status (UIC and iodine-to-creatinine ratio) and birth weight, birth weight centile (primary outcome), small for gestational age (SGA) and spontaneous preterm birth. Median UIC was highest in Manchester (139 µg/L, 95% confidence intervals (CI): 126, 158) and London (130 µg/L, 95% CI: 114, 177) and lowest in Leeds (116 µg/L, 95% CI: 99, 135), but the proportion with UIC <50 µg/L was <20% in all three cities. No evidence of an association was observed between UIC and birth weight centile (-0.2% per 50 µg/L increase in UIC, 95% CI: -1.3, 0.8), nor with odds of spontaneous preterm birth (odds ratio = 1.00, 95% CI: 0.84, 1.20). Given the finding of iodine concentrations being insufficient according to World Health Organization (WHO) guidelines amongst pregnant women across all three cities, further studies may be needed to explore implications for maternal thyroid function and longer-term child health outcomes.


Assuntos
Iodo/deficiência , Estado Nutricional , Complicações na Gravidez/epidemiologia , Resultado da Gravidez/epidemiologia , Fenômenos Fisiológicos da Nutrição Pré-Natal , Adulto , Peso ao Nascer , Cidades , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Recém-Nascido Pequeno para a Idade Gestacional , Iodo/urina , Avaliação Nutricional , Gravidez , Complicações na Gravidez/etiologia , Complicações na Gravidez/urina , Nascimento Prematuro/epidemiologia , Nascimento Prematuro/etiologia , Diagnóstico Pré-Natal/métodos , Reino Unido/epidemiologia
16.
Gut ; 68(5): 814-828, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-29848778

RESUMO

OBJECTIVE: Anti-tumour necrosis factor (TNF) antibodies are successfully used for treatment of Crohn's disease. Nevertheless, approximately 40% of patients display failure to anti-TNF therapy. Here, we characterised molecular mechanisms that are associated with endoscopic resistance to anti-TNF therapy. DESIGN: Mucosal and blood cells were isolated from patients with Crohn's disease prior and during anti-TNF therapy. Cytokine profiles, cell surface markers, signalling proteins and cell apoptosis were assessed by microarray, immunohistochemistry, qPCR, ELISA, whole organ cultures and FACS. RESULTS: Responders to anti-TNF therapy displayed a significantly higher expression of TNF receptor 2 (TNFR2) but not IL23R on T cells than non-responders prior to anti-TNF therapy. During anti-TNF therapy, there was a significant upregulation of mucosal IL-23p19, IL23R and IL-17A in anti-TNF non-responders but not in responders. Apoptosis-resistant TNFR2+IL23R+ T cells were significantly expanded in anti-TNF non-responders compared with responders, expressed the gut tropic integrins α4ß7, and exhibited increased expression of IFN-γ, T-bet, IL-17A and RORγt compared with TNFR2+IL23R- cells, indicating a mixed Th1/Th17-like phenotype. Intestinal TNFR2+IL23R+ T cells were activated by IL-23 derived from CD14+ macrophages, which were significantly more present in non-responders prior to anti-TNF treatment. Administration of IL-23 to anti-TNF-treated mucosal organ cultures led to the expansion of CD4+IL23R+TNFR2+ lymphocytes. Functional studies demonstrated that anti-TNF-induced apoptosis in mucosal T cells is abrogated by IL-23. CONCLUSIONS: Expansion of apoptosis-resistant intestinal TNFR2+IL23R+ T cells is associated with resistance to anti-TNF therapy in Crohn's disease. These findings identify IL-23 as a suitable molecular target in patients with Crohn's disease refractory to anti-TNF therapy.


Assuntos
Doença de Crohn/metabolismo , Resistência a Medicamentos , Fármacos Gastrointestinais/uso terapêutico , Receptores de Interleucina/metabolismo , Receptores Tipo II do Fator de Necrose Tumoral/metabolismo , Linfócitos T/fisiologia , Adalimumab/uso terapêutico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença de Crohn/tratamento farmacológico , Doença de Crohn/patologia , Humanos , Infliximab/uso terapêutico , Interleucina-17/metabolismo , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Masculino , Pessoa de Meia-Idade , Adulto Jovem
17.
Anat Sci Educ ; 12(2): 164-172, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30107081

RESUMO

Students' engagement with two-dimensional (2D) representations as opposed to three-dimensional (3D) representations of anatomy such as in dissection, is significant in terms of the depth of their comprehension. This qualitative study aimed to understand how students learned anatomy using observational and drawing activities that included touch, called haptics. Five volunteer second year medical students at the University of Cape Town participated in a six-day educational intervention in which a novel "haptico-visual observation and drawing" (HVOD) method was employed. Data were collected through individual interviews as well as a focus group discussion. The HVOD method was successfully applied by all the participants, who reported an improvement of their cognitive understanding and memorization of the 3D form of the anatomical part. All the five participants described the development of a "mental picture" of the object as being central to "deep learning." The use of the haptic senses coupled with the simultaneous act of drawing enrolled sources of information that were reported by the participants to have enabled better memorization. We postulate that the more sources of information about an object, the greater degree of complexity could be appreciated, and therefore the more clearly it could be captured and memorized. The inclusion of haptics has implications for cadaveric dissection versus non-cadaveric forms of learning. This study was limited by its sample size as well as the bias and position of the researchers, but the sample of five produced a sufficient amount of data to generate a conceptual model and hypothesis.


Assuntos
Anatomia/educação , Instrução por Computador/métodos , Educação de Graduação em Medicina/métodos , Imageamento Tridimensional , Estudantes de Medicina/psicologia , Adulto , Cadáver , Dissecação/educação , Avaliação Educacional/estatística & dados numéricos , Feminino , Humanos , Masculino , Pesquisa Qualitativa , África do Sul , Estudantes de Medicina/estatística & dados numéricos , Adulto Jovem
18.
J Appl Stat ; 45(14): 2658-2676, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30294060

RESUMO

We introduce a novel data reduction technique whereby we select a subset of tiles to "cover" maximally events of interest in large-scale biological datasets (e.g., genetic mutations), while minimizing the number of tiles. A tile is a genomic unit capturing one or more biological events, such as a sequence of base pairs that can be sequenced and observed simultaneously. The goal is to reduce significantly the number of tiles considered to those with areas of dense events in a cohort, thus saving on cost and enhancing interpretability. However, the reduction should not come at the cost of too much information, allowing for sensible statistical analysis after its application. We envisage application of our methods to a variety of high throughput data types, particularly those produced by next generation sequencing (NGS) experiments. The procedure is cast as a convex optimization problem, which is presented, along with methods of its solution. The method is demonstrated on a large dataset of somatic mutations spanning 5000+ patients, each having one of 29 cancer types. Applied to these data, our method dramatically reduces the number of gene locations required for broad coverage of patients and their mutations, giving subject specialists a more easily interpretable snapshot of recurrent mutational profiles in these cancers. The locations identified coincide with previously identified cancer genes. Finally, despite considerable data reduction, we show that our covering designs preserve the cancer discrimination ability of multinomial logistic regression models trained on all of the locations (> 1M).

19.
Plant Cell Environ ; 41(11): 2600-2616, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29869794

RESUMO

Potato is an important staple food with increasing popularity worldwide. Elevated temperatures significantly impair tuber yield and quality. Breeding heat-tolerant cultivars is therefore an urgent need to ensure sustainable potato production in the future. An integrated approach combining physiology, biochemistry, and molecular biology was undertaken to contribute to a better understanding of heat effects on source- (leaves) and sink-organs (tubers) in a heat-susceptible cultivar. An experimental set-up was designed allowing tissue-specific heat application. Elevated day and night (29°C/27°C) temperatures impaired photosynthesis and assimilate production. Biomass allocation shifted away from tubers towards leaves indicating reduced sink strength of developing tubers. Reduced sink strength of tubers was paralleled by decreased sucrose synthase activity and expression under elevated temperatures. Heat-mediated inhibition of tuber growth coincided with a decreased expression of the phloem-mobile tuberization signal SP6A in leaves. SP6A expression and photosynthesis were also affected, when only the belowground space was heated, and leaves were kept under control conditions. By contrast, the negative effects on tuber metabolism were attenuated, when only the shoot was subjected to elevated temperatures. This, together with transcriptional changes discussed, indicated a bidirectional communication between leaves and tubers to adjust the source capacity and/or sink strength to environmental conditions.


Assuntos
Folhas de Planta/fisiologia , Tubérculos/fisiologia , Solanum tuberosum/fisiologia , Biomassa , Temperatura Alta , Fotossíntese , Tubérculos/crescimento & desenvolvimento , Tubérculos/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Solanum tuberosum/crescimento & desenvolvimento , Solanum tuberosum/metabolismo , Amido/metabolismo , Açúcares/metabolismo , Transcriptoma
20.
Artigo em Inglês | MEDLINE | ID: mdl-29555628

RESUMO

AB-423 is a member of the sulfamoylbenzamide (SBA) class of hepatitis B virus (HBV) capsid inhibitors in phase 1 clinical trials. In cell culture models, AB-423 showed potent inhibition of HBV replication (50% effective concentration [EC50] = 0.08 to 0.27 µM; EC90 = 0.33 to 1.32 µM) with no significant cytotoxicity (50% cytotoxic concentration > 10 µM). Addition of 40% human serum resulted in a 5-fold increase in the EC50s. AB-423 inhibited HBV genotypes A through D and nucleos(t)ide-resistant variants in vitro Treatment of HepDES19 cells with AB-423 resulted in capsid particles devoid of encapsidated pregenomic RNA and relaxed circular DNA (rcDNA), indicating that it is a class II capsid inhibitor. In a de novo infection model, AB-423 prevented the conversion of encapsidated rcDNA to covalently closed circular DNA, presumably by interfering with the capsid uncoating process. Molecular docking of AB-423 into crystal structures of heteroaryldihydropyrimidines and an SBA and biochemical studies suggest that AB-423 likely also binds to the dimer-dimer interface of core protein. In vitro dual combination studies with AB-423 and anti-HBV agents, such as nucleos(t)ide analogs, RNA interference agents, or interferon alpha, resulted in additive to synergistic antiviral activity. Pharmacokinetic studies with AB-423 in CD-1 mice showed significant systemic exposures and higher levels of accumulation in the liver. A 7-day twice-daily administration of AB-423 in a hydrodynamic injection mouse model of HBV infection resulted in a dose-dependent reduction in serum HBV DNA levels, and combination with entecavir or ARB-1467 resulted in a trend toward antiviral activity greater than that of either agent alone, consistent with the results of the in vitro combination studies. The overall preclinical profile of AB-423 supports its further evaluation for safety, pharmacokinetics, and antiviral activity in patients with chronic hepatitis B.


Assuntos
Antivirais/farmacologia , Capsídeo/metabolismo , Vírus da Hepatite B/efeitos dos fármacos , Hepatite B/tratamento farmacológico , Montagem de Vírus/efeitos dos fármacos , Animais , Sítios de Ligação , Linhagem Celular Tumoral , DNA Circular/metabolismo , DNA Viral/sangue , DNA Viral/metabolismo , Feminino , Guanina/análogos & derivados , Guanina/farmacologia , Vírus da Hepatite B/crescimento & desenvolvimento , Humanos , Camundongos , Simulação de Acoplamento Molecular , Ligação Proteica , RNA Viral/genética
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