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1.
Photochem Photobiol Sci ; 22(5): 1093-1127, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37129840

RESUMO

Variations in stratospheric ozone and changes in the aquatic environment by climate change and human activity are modifying the exposure of aquatic ecosystems to UV radiation. These shifts in exposure have consequences for the distributions of species, biogeochemical cycles, and services provided by aquatic ecosystems. This Quadrennial Assessment presents the latest knowledge on the multi-faceted interactions between the effects of UV irradiation and climate change, and other anthropogenic activities, and how these conditions are changing aquatic ecosystems. Climate change results in variations in the depth of mixing, the thickness of ice cover, the duration of ice-free conditions and inputs of dissolved organic matter, all of which can either increase or decrease exposure to UV radiation. Anthropogenic activities release oil, UV filters in sunscreens, and microplastics into the aquatic environment that are then modified by UV radiation, frequently amplifying adverse effects on aquatic organisms and their environments. The impacts of these changes in combination with factors such as warming and ocean acidification are considered for aquatic micro-organisms, macroalgae, plants, and animals (floating, swimming, and attached). Minimising the disruptive consequences of these effects on critical services provided by the world's rivers, lakes and oceans (freshwater supply, recreation, transport, and food security) will not only require continued adherence to the Montreal Protocol but also a wider inclusion of solar UV radiation and its effects in studies and/or models of aquatic ecosystems under conditions of the future global climate.


Assuntos
Perda de Ozônio , Ozônio , Animais , Humanos , Ozônio Estratosférico , Raios Ultravioleta , Mudança Climática , Ecossistema , Concentração de Íons de Hidrogênio , Plásticos , Água do Mar
2.
Microb Ecol ; 86(1): 282-296, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35608637

RESUMO

Heavily pigmented glacier ice algae Ancylonema nordenskiöldii and Ancylonema alaskanum (Zygnematophyceae, Streptophyta) reduce the bare ice albedo of the Greenland Ice Sheet, amplifying melt from the largest cryospheric contributor to eustatic sea-level rise. Little information is available about glacier ice algae interactions with other microbial communities within the surface ice environment, including fungi, which may be important for sustaining algal bloom development. To address this substantial knowledge gap and investigate the nature of algal-fungal interactions, an ex situ co-cultivation experiment with two species of fungi, recently isolated from the surface of the Greenland Ice Sheet (here proposed new species Penicillium anthracinoglaciei Perini, Frisvad and Zalar, Mycobank (MB 835602), and Articulospora sp.), and the mixed microbial community dominated by glacier ice algae was performed. The utilization of the dark pigment purpurogallin carboxylic acid-6-O-ß-D-glucopyranoside (C18H18O12) by the two fungi was also evaluated in a separate experiment. P. anthracinoglaciei was capable of utilizing and converting the pigment to purpurogallin carboxylic acid, possibly using the sugar moiety as a nutrient source. Furthermore, after 3 weeks of incubation in the presence of P. anthracinoglaciei, a significantly slower decline in the maximum quantum efficiency (Fv/Fm, inverse proxy of algal stress) in glacier ice algae, compared to other treatments, was evident, suggesting a positive relationship between these species. Articulospora sp. did uptake the glycosylated purpurogallin, but did not seem to be involved in its conversion to aglycone derivative. At the end of the incubation experiments and, in conjunction with increased algal mortality, we detected a substantially increasing presence of the zoosporic fungi Chytridiomycota suggesting an important role for them as decomposers or parasites of glacier ice algae.


Assuntos
Camada de Gelo , Estreptófitas , Camada de Gelo/microbiologia , Groenlândia , Benzocicloeptenos , Fungos
3.
Photochem Photobiol Sci ; 21(3): 275-301, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35191005

RESUMO

The Environmental Effects Assessment Panel of the Montreal Protocol under the United Nations Environment Programme evaluates effects on the environment and human health that arise from changes in the stratospheric ozone layer and concomitant variations in ultraviolet (UV) radiation at the Earth's surface. The current update is based on scientific advances that have accumulated since our last assessment (Photochem and Photobiol Sci 20(1):1-67, 2021). We also discuss how climate change affects stratospheric ozone depletion and ultraviolet radiation, and how stratospheric ozone depletion affects climate change. The resulting interlinking effects of stratospheric ozone depletion, UV radiation, and climate change are assessed in terms of air quality, carbon sinks, ecosystems, human health, and natural and synthetic materials. We further highlight potential impacts on the biosphere from extreme climate events that are occurring with increasing frequency as a consequence of climate change. These and other interactive effects are examined with respect to the benefits that the Montreal Protocol and its Amendments are providing to life on Earth by controlling the production of various substances that contribute to both stratospheric ozone depletion and climate change.


Assuntos
Perda de Ozônio , Ozônio , Mudança Climática , Ecossistema , Humanos , Ozônio/química , Ozônio Estratosférico , Raios Ultravioleta
4.
Photochem Photobiol Sci ; 20(1): 1-67, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33721243

RESUMO

This assessment by the Environmental Effects Assessment Panel (EEAP) of the United Nations Environment Programme (UNEP) provides the latest scientific update since our most recent comprehensive assessment (Photochemical and Photobiological Sciences, 2019, 18, 595-828). The interactive effects between the stratospheric ozone layer, solar ultraviolet (UV) radiation, and climate change are presented within the framework of the Montreal Protocol and the United Nations Sustainable Development Goals. We address how these global environmental changes affect the atmosphere and air quality; human health; terrestrial and aquatic ecosystems; biogeochemical cycles; and materials used in outdoor construction, solar energy technologies, and fabrics. In many cases, there is a growing influence from changes in seasonality and extreme events due to climate change. Additionally, we assess the transmission and environmental effects of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which is responsible for the COVID-19 pandemic, in the context of linkages with solar UV radiation and the Montreal Protocol.

5.
BJOG ; 128(10): 1635-1644, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33586324

RESUMO

OBJECTIVE: To determine the optimal total serum bile acid (TSBA) threshold and sampling time for accurate intrahepatic cholestasis of pregnancy (ICP) diagnosis. DESIGN: Case-control, retrospective cohort studies. SETTING: Antenatal clinics, clinical research facilities. POPULATION: Women with ICP or uncomplicated pregnancies. METHODS: Serial TSBA measurements were performed pre-/postprandially in 42 women with ICP or uncomplicated pregnancy. Third-trimester non-fasting TSBA reference ranges were calculated from 561 women of black, south Asian and white ethnicity. Rates of adverse perinatal outcomes for women with ICP but peak non-fasting TSBA below the upper reference range limit were compared with those in healthy populations. MAIN OUTCOME MEASURES: Sensitivity and specificity of common TSBA thresholds for ICP diagnosis, using fasting and postprandial TSBA. Calculation of normal reference ranges of non-fasting TSBA. RESULTS: Concentrations of TSBA increased markedly postprandially in all groups, with overlap between healthy pregnancy and mild ICP (TSBA <40 µmol/l). The specificity of ICP diagnosis was higher when fasting, but corresponded to <30% sensitivity for diagnosis of mild disease. Using TSBA ≥40 µmol/l to define severe ICP, fasting measurements identified 9% (1/11), whereas non-fasting measurements detected over 91% with severe ICP. The highest upper limit of the non-fasting TSBA reference range was 18.3 µmol/l (95% confidence interval: 15.0-35.6 µmol/l). A re-evaluation of published ICP meta-analysis data demonstrated no increase in spontaneous preterm birth or stillbirth in women with TSBA <19 µmol/l. CONCLUSIONS: Postprandial TSBA levels are required to identify high-risk ICP pregnancies (TSBA ≥40 µmol/l). The postprandial rise in TSBA in normal pregnancy indicates that a non-fasting threshold of ≥19 µmol/l would improve diagnostic accuracy. TWEETABLE ABSTRACT: Non-fasting bile acids improve the diagnostic accuracy of intrahepatic cholestasis of pregnancy diagnosis.


Assuntos
Ácidos e Sais Biliares/sangue , Colestase Intra-Hepática/diagnóstico , Complicações na Gravidez/diagnóstico , Diagnóstico Pré-Natal , Adulto , Biomarcadores/sangue , Estudos de Casos e Controles , Colestase Intra-Hepática/sangue , Estudos de Coortes , Feminino , Humanos , Gravidez , Complicações na Gravidez/sangue , Estudos Retrospectivos , Sensibilidade e Especificidade
6.
BJOG ; 128(6): 1066-1075, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33063439

RESUMO

OBJECTIVE: To evaluate whether a particular group of women with intrahepatic cholestasis of pregnancy (ICP), based on their presenting characteristics, would benefit from treatment with ursodeoxycholic acid (UDCA). DESIGN: Secondary analysis of the PITCHES trial (ISRCTN91918806). SETTING: United Kingdom. POPULATION OR SAMPLE: 527 women with ICP. METHODS: Subgroup analyses were performed to determine whether baseline bile acid concentrations or baseline itch scores moderated a woman's response to treatment with UDCA. MAIN OUTCOME MEASURES: Bile acid concentration and itch score. RESULTS: In women with baseline bile acid concentrations less than 40 µmol/l, treatment with UDCA resulted in increased post-randomisation bile acid concentrations (geometric mean ratio 1.19, 95% CI 1.00-1.41, P = 0.048). A test of interaction showed no significance (P = 0.647). A small, clinically insignificant difference was seen in itch response in women with a high baseline itch score (-6.0 mm, 95% CI -11.80 to -0.21, P = 0.042), with a test of interaction not showing significance (P = 0.640). Further subgroup analyses showed no significance. Across all women there was a weak relationship between bile acid concentrations and itch severity. CONCLUSIONS: There was no subgroup of women with ICP in whom a beneficial effect of treatment with UDCA on bile acid concentration or itch score could be identified. This confirms that its routine use in women with this condition for improvement of bile acid concentration or itch score should be reconsidered. TWEETABLE ABSTRACT: PITCHES: No group of women with ICP has been found in whom UDCA reduces bile acid concentrations or pruritus.


Assuntos
Ácidos e Sais Biliares/sangue , Colestase Intra-Hepática , Complicações na Gravidez , Prurido , Ácido Ursodesoxicólico , Adulto , Colagogos e Coleréticos/administração & dosagem , Colagogos e Coleréticos/efeitos adversos , Colestase Intra-Hepática/sangue , Colestase Intra-Hepática/diagnóstico , Colestase Intra-Hepática/tratamento farmacológico , Colestase Intra-Hepática/fisiopatologia , Método Duplo-Cego , Feminino , Humanos , Avaliação de Resultados em Cuidados de Saúde , Gravidez , Complicações na Gravidez/sangue , Complicações na Gravidez/diagnóstico , Complicações na Gravidez/tratamento farmacológico , Complicações na Gravidez/fisiopatologia , Prurido/diagnóstico , Prurido/tratamento farmacológico , Prurido/etiologia , Índice de Gravidade de Doença , Natimorto/epidemiologia , Avaliação de Sintomas/métodos , Reino Unido , Ácido Ursodesoxicólico/administração & dosagem , Ácido Ursodesoxicólico/efeitos adversos
7.
Int J Obes (Lond) ; 44(9): 1958-1969, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32678325

RESUMO

Diet has important effects on normal physiology and the potential deleterious effects of high fat diets and obesity on male reproductive health are being increasingly described. We conducted a histological review of the effects of chronic high fat (HF) diet (using a mouse model fed a 45% fat diet for 21 weeks) with a discovery proteomic study to assess for changes in the abundance of proteins in the testis. Mice on a HF diet became obese and developed glucose intolerance. Using mass spectrometry, we identify 102 proteins affected in the testis of obese mice. These included structural proteins important for the blood testis barrier (filamin A, FLNA), proteins involved in oxidative stress responses (spermatogenesis associated 20, SPATA-20) and lipid homoeostasis (sterol regulatory element-binding protein 2, SREBP2 and apolipoprotein A1, APOA1). In addition, an important regulator protein paraspeckle component 1, PSPC-1, which interacts with the androgen receptor was significantly downregulated. Proteomic data was validated using both Western blotting and immunostaining which confirmed and localised protein expression in both mouse and human testis using biopsy specimens. This study focused mainly on the abnormalities that occurred at the protein level and as a result, we have identified several candidate proteins and conducted pathway analysis around the effects of HF diet on the testis providing novel insights not previously described. Some of the identified targets could be targeted therapeutically and future work is directed in this area.


Assuntos
Dieta Hiperlipídica/efeitos adversos , Gorduras na Dieta/farmacologia , Obesidade/metabolismo , Proteoma/efeitos dos fármacos , Testículo , Animais , Humanos , Masculino , Camundongos , Testículo/efeitos dos fármacos , Testículo/patologia
8.
Photochem Photobiol Sci ; 19(5): 542-584, 2020 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-32364555

RESUMO

This assessment, by the United Nations Environment Programme (UNEP) Environmental Effects Assessment Panel (EEAP), one of three Panels informing the Parties to the Montreal Protocol, provides an update, since our previous extensive assessment (Photochem. Photobiol. Sci., 2019, 18, 595-828), of recent findings of current and projected interactive environmental effects of ultraviolet (UV) radiation, stratospheric ozone, and climate change. These effects include those on human health, air quality, terrestrial and aquatic ecosystems, biogeochemical cycles, and materials used in construction and other services. The present update evaluates further evidence of the consequences of human activity on climate change that are altering the exposure of organisms and ecosystems to UV radiation. This in turn reveals the interactive effects of many climate change factors with UV radiation that have implications for the atmosphere, feedbacks, contaminant fate and transport, organismal responses, and many outdoor materials including plastics, wood, and fabrics. The universal ratification of the Montreal Protocol, signed by 197 countries, has led to the regulation and phase-out of chemicals that deplete the stratospheric ozone layer. Although this treaty has had unprecedented success in protecting the ozone layer, and hence all life on Earth from damaging UV radiation, it is also making a substantial contribution to reducing climate warming because many of the chemicals under this treaty are greenhouse gases.


Assuntos
Mudança Climática , Ozônio Estratosférico , Raios Ultravioleta , Saúde Ambiental , Humanos , Microplásticos , Nações Unidas
9.
BJOG ; 127(7): 876-884, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32012415

RESUMO

OBJECTIVE: To determine maternal, obstetric and neonatal outcomes in a cohort of women with primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC). DESIGN: Retrospective cohort study. SETTING: Ten specialist centres managing pregnant women with liver disease. POPULATION: Women with a diagnosis of PBC and PSC and a pregnancy of ≥20 completed weeks of gestation. METHODS: Retrospective case notes review. MAIN OUTCOME MEASURES: Adverse outcomes were defined as: maternal - development of ascites, variceal bleeding, encephalopathy and jaundice; obstetric events - gestational hypertension, pre-eclampsia and postpartum haemorrhage; and neonatal - stillbirth, preterm delivery and admission to neonatal unit. The relationship of alanine transferase (ALT) and bile acid levels with gestation at delivery was studied. RESULTS: The first recorded pregnancies of 34 women with PSC and 27 women with PBC were analysed. There were 60 live births and one intrapartum stillbirth that did not occur in the context of maternal cholestasis. The overall median gestation of delivery was 38 weeks but the rate of preterm birth was 28% (17/61 deliveries), 76% (13/17) of which were spontaneous. Gestation at birth negatively correlated with maternal serum ALT concentration at booking (P = 0.017) and serum bile acid concentration during pregnancy (P = 0.016). There were no other significant correlations and maternal and neonatal outcomes were good. CONCLUSIONS: Pregnancy in PBC and PSC is well tolerated, but women should be counselled regarding the increased risk of preterm birth. Measurement of maternal ALT and bile acids may help identify women at risk of preterm delivery. TWEETABLE ABSTRACT: Pregnancy in women with PBC and PSC is well tolerated; however, rates of preterm birth are high and are related to maternal bile acid levels.


Assuntos
Colangite Esclerosante , Cirrose Hepática Biliar , Complicações na Gravidez , Nascimento Prematuro , Adulto , Colangite Esclerosante/complicações , Colangite Esclerosante/diagnóstico , Colangite Esclerosante/epidemiologia , Feminino , Humanos , Recém-Nascido , Cirrose Hepática Biliar/complicações , Cirrose Hepática Biliar/diagnóstico , Cirrose Hepática Biliar/epidemiologia , Testes de Função Hepática/métodos , Gravidez , Complicações na Gravidez/diagnóstico , Complicações na Gravidez/epidemiologia , Resultado da Gravidez/epidemiologia , Nascimento Prematuro/etiologia , Nascimento Prematuro/prevenção & controle , Estudos Retrospectivos , Medição de Risco , Reino Unido/epidemiologia
10.
BJOG ; 126(13): 1633-1640, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31483939

RESUMO

OBJECTIVE: To evaluate enzymatic total serum bile acid quantification as a monitoring strategy for women with intrahepatic cholestasis of pregnancy (ICP) treated with ursodeoxycholic acid (UDCA). DESIGN: Cohort. SETTING: One UK university hospital. POPULATION: 29 ICP cases treated with UDCA. METHODS: Serial samples were collected prospectively throughout gestation. Total serum bile acids were measured enzymatically and individual bile acids by high-performance liquid chromatography-tandem mass spectrometry. Data were log-transformed and analysed with random effects generalised least square regression. MAIN OUTCOME MEASURES: The relationship between enzymatic total bile acid measurements and individual bile acid concentrations after UDCA treatment. RESULTS: In untreated women, cholic acid was the principal bile acid (51%) and UDCA concentrations were <0.5%, whereas UDCA constituted 60% (IQR 43-69) of serum bile acids following treatment and cholic acid fell to <20%. Changes in the total bile acid measurement reflected similar alterations in the concentrations of the pathologically elevated bile acids, e.g. a two-fold increase in enzymatic total bile acids is accompanied by approximately a two-fold increase in cholic acid and chenodeoxycholic acid at most UDCA doses (P < 0.001). Most of the effects of UDCA on cholic acid occur in the first week of treatment (60% relative reduction, P = 0.025, 95% CI 0.2-0.9, from 10 micromol/l (4.7-17.6) to 3.5 micromol/l (1.4-7.5). CONCLUSION: Ursodeoxycholic acid becomes the main component of the bile acid measurement after treatment. Enzymatic total bile acid assays are good predictors of both cholic acid and chenodeoxycholic acid, the primary bile acids that are raised prior to treatment. TWEETABLE ABSTRACT: Ursodeoxycholic acid constitutes approximately 60% of the bile acid measurement and reduces pathological cholic acid in treated women.


Assuntos
Ácidos e Sais Biliares/sangue , Colagogos e Coleréticos/uso terapêutico , Colestase Intra-Hepática/sangue , Colestase Intra-Hepática/tratamento farmacológico , Complicações na Gravidez/sangue , Complicações na Gravidez/tratamento farmacológico , Ácido Ursodesoxicólico/uso terapêutico , Adulto , Feminino , Humanos , Testes de Função Hepática , Gravidez , Estudos Prospectivos , Resultado do Tratamento
11.
Photosynth Res ; 137(3): 377-388, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29663190

RESUMO

Photoacclimation by strains of Haslea "blue" diatom species H. ostrearia and H. silbo sp. nov. ined. was investigated with rapid light curves and induction-recovery curves using fast repetition rate fluorescence. Cultures were grown to exponential phase under 50 µmol m-2 s-1 photosynthetic available radiation (PAR) and then exposed to non-sequential rapid light curves where, once electron transport rate (ETR) had reached saturation, light intensity was decreased and then further increased prior to returning to near growth light intensity. The non-sequential rapid light curve revealed that ETR was not proportional to the instantaneously applied light intensity, due to rapid photoacclimation. Changes in the effective absorption cross sections for open PSII reaction centres (σPSII') or reaction centre connectivity (ρ) did not account for the observed increases in ETR under extended high light. σPSII' in fact decreased as a function of a time-dependent induction of regulated excitation dissipation Y(NPQ), once cells were at or above a PAR coinciding with saturation of ETR. Instead, the observed increases in ETR under extended high light were explained by an increase in the rate of PSII reopening, i.e. QA- oxidation. This acceleration of electron transport was strictly light dependent and relaxed within seconds after a return to low light or darkness. The time-dependent nature of ETR upregulation and regulated NPQ induction was verified using induction-recovery curves. Our findings show a time-dependent induction of excitation dissipation, in parallel with very rapid photoacclimation of electron transport, which combine to make ETR independent of short-term changes in PAR. This supports a selective advantage for these diatoms when exposed to fluctuating light in their environment.


Assuntos
Diatomáceas/fisiologia , Transporte de Elétrons/efeitos da radiação , Fotossíntese/efeitos da radiação , Aclimatação , Escuridão , Diatomáceas/efeitos da radiação , Regulação para Baixo , Fluorescência , Luz , Complexo de Proteína do Fotossistema II/efeitos da radiação , Fatores de Tempo , Regulação para Cima
12.
Photochem Photobiol Sci ; 17(2): 127-179, 2018 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-29404558

RESUMO

The Environmental Effects Assessment Panel (EEAP) is one of three Panels of experts that inform the Parties to the Montreal Protocol. The EEAP focuses on the effects of UV radiation on human health, terrestrial and aquatic ecosystems, air quality, and materials, as well as on the interactive effects of UV radiation and global climate change. When considering the effects of climate change, it has become clear that processes resulting in changes in stratospheric ozone are more complex than previously held. Because of the Montreal Protocol, there are now indications of the beginnings of a recovery of stratospheric ozone, although the time required to reach levels like those before the 1960s is still uncertain, particularly as the effects of stratospheric ozone on climate change and vice versa, are not yet fully understood. Some regions will likely receive enhanced levels of UV radiation, while other areas will likely experience a reduction in UV radiation as ozone- and climate-driven changes affect the amounts of UV radiation reaching the Earth's surface. Like the other Panels, the EEAP produces detailed Quadrennial Reports every four years; the most recent was published as a series of seven papers in 2015 (Photochem. Photobiol. Sci., 2015, 14, 1-184). In the years in between, the EEAP produces less detailed and shorter Update Reports of recent and relevant scientific findings. The most recent of these was for 2016 (Photochem. Photobiol. Sci., 2017, 16, 107-145). The present 2017 Update Report assesses some of the highlights and new insights about the interactive nature of the direct and indirect effects of UV radiation, atmospheric processes, and climate change. A full 2018 Quadrennial Assessment, will be made available in 2018/2019.

13.
BJOG ; 125(6): 719-727, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-28872770

RESUMO

OBJECTIVE: To examine the management and outcomes of adrenal tumours in pregnancy. DESIGN: A national observational, cohort study over 4 years using the UK Obstetric Surveillance System (UKOSS). SETTING: Consultant-led obstetric units. PATIENTS: Women with phaeochromocytoma, primary aldosteronism or Cushing's syndrome diagnosed before or during pregnancy. METHODS: Clinical features of UKOSS cases were compared with those of women with adrenal tumours reported from 1985-2015. Nested case-control comparisons involving the UKOSS cases as well as those identified in the literature were performed for pregnancy outcome data using UKOSS controls with uncomplicated singleton (n = 2250) pregnancy and data from the Office of National Statistics (ONS). MAIN OUTCOME MEASURES: Incidence, management and frequency of adverse maternal and offspring outcomes of adrenal tumours in pregnancy. RESULTS: Fifteen pregnant women met the inclusion criteria: ten phaeochromocytoma, three primary aldosteronism and two Cushing's syndrome. All of the tumours had an incidence rate <2 per 100 000 pregnancies. Clinical symptoms were similar to those in non-pregnant women due to the hormones released. All women had severe hypertension, and in those diagnosed in pregnancy prior to conception. There was a significantly increased risk of adverse pregnancy outcomes in affected women, with increased rates of stillbirth, preterm labour and operative delivery. CONCLUSIONS: Adrenal tumours are associated with increased risks for pregnant women and their babies. Data on these tumours to inform practice are limited and international collaborative efforts are likely to be needed. TWEETABLE ABSTRACT: Study of hormone-secreting adrenal tumours in pregnancy linked with high BP and high rates of fetal morbidity.


Assuntos
Neoplasias das Glândulas Suprarrenais/complicações , Hipertensão/complicações , Vigilância da População , Complicações Neoplásicas na Gravidez/epidemiologia , Complicações Neoplásicas na Gravidez/etiologia , Neoplasias das Glândulas Suprarrenais/metabolismo , Estudos de Casos e Controles , Feminino , Humanos , Incidência , Trabalho de Parto Prematuro/epidemiologia , Trabalho de Parto Prematuro/etiologia , Gravidez , Complicações Neoplásicas na Gravidez/metabolismo , Resultado da Gravidez , Fatores de Risco , Natimorto/epidemiologia , Reino Unido/epidemiologia
14.
BJOG ; 129(3): 378, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34651410
15.
Hum Reprod ; 31(12): 2681-2688, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27664209

RESUMO

STUDY QUESTION: Are novel circulating placental markers prokineticin-1 (PK-1), soluble fms-like tyrosine kinase-1 (sFlt-1), soluble endoglin (sEng) and placental growth factor (PlGF) associated with late miscarriage in asymptomatic first trimester pregnant women? SUMMARY ANSWER: Increased serum sFlt-1 or PlGF, but not sEng or PK-1, were significantly associated with reduced miscarriage risk after adjustment for age, BMI, gestational age, smoking and blood pressure. WHAT IS KNOWN ALREADY: Abnormal placental development is observed in two-thirds of miscarriages. Identifying women at high risk of late miscarriage could help diagnose potentially treatable causes of miscarriage such as infection, thrombosis or immunological disease. Recently, the circulating placental markers PK-1, sFlt-1, sEng and PlGF have been identified; however, it is not known if circulating levels of these markers are associated with late miscarriage. STUDY DESIGN, SIZE, DURATION: A single-centre observational cohort study with prospectively collected data was carried out at a tertiary care centre 2010-2012, in 993 asymptomatic pregnant women. Plasma PK-1, and serum sEng, sFlt-1 and PlGF were measured once in each patient during the antenatal booking visit, and pregnancy outcome was monitored prospectively. Less than 1% of patients were lost to follow-up. Multiples of median (MOM) levels were calculated to adjust for gestational age. PARTICIPANTS/MATERIALS, SETTING, METHODS: Nine-hundred and ninety-three asymptomatic pregnant women attending antenatal clinic for a routine booking antenatal appointment were recruited to the study, of whom 12 were lost to follow-up and excluded from analysis. Of the cohort, 50 of the remaining 981 women suffered late miscarriage. MAIN RESULTS AND THE ROLE OF CHANCE: Gestation-adjusted sEng, sFlt-1 and PlGF levels were 11% (P < 0.01), 36% (P < 0.001) and 30% (P < 0.001), respectively, lower in women who later suffered miscarriage compared with unaffected pregnancies, while PK-1 did not differ significantly. Logistic regression modelling suggested that increased sFlt-1 (odds ratio (OR) 0.15 95% confidence interval [0.08-0.26], P = 0.0001) and PlGF (OR 0.02 [0.01-0.05], P = 0.0001), but not sEng, were associated with reduced miscarriage risk after adjustment for age, BMI, gestational age, smoking and blood pressure. The combination of sFlt-1 and PlGF did not improve the diagnostic accuracy beyond the use of sFlt-1. LIMITATIONS, REASONS FOR CAUTION: First trimester levels of sFlt-1 and PlGF, but not sEng or PK-1, were associated with late miscarriage risk in asymptomatic women. However, a new prospective study is now required to investigate the utility of these markers to predict early (<10 weeks) and late miscarriage, as well as to predict other complications of pregnancy. WIDER IMPLICATIONS OF THE FINDINGS: Our data suggest that circulating sFlt-1 and PlGF, but not sEng or PK-1, are independently associated with late miscarriage risk in asymptomatic pregnant women attending their antenatal visit. Therefore, sFlt-1 and PlGF may represent novel markers of placental viability. These data further our understanding of placental function, and have important potential implications for utilizing novel hormonal markers to detect adverse clinical outcomes during pregnancy. STUDY FUNDING/COMPETING INTERESTS: The authors have no competing interests. The Section of Investigative Medicine is funded by grants from the MRC, BBSRC, NIHR, an Integrative Mammalian Biology (IMB) Capacity Building Award, an FP7-HEALTH-2009-241592 EuroCHIP grant and is supported by the NIHR Imperial Biomedical Research Centre Funding Scheme. This project was funded by an NIHR grant (reference: CDF-2009-02-05). The following authors are also funded as follows: CNJ is supported by an NIHR Clinical Lectureship and AMS/ Wellcome Starter Grant for Clinical Lecturers. AA and ANC are supported by NIHR academic clinical lectureships. CI-E is supported by an Imperial College Healthcare NHS Trust Charity Research Fellowship. WSD is supported by an NIHR Career Development Fellowship. TRIAL REGISTRATION NUMBER: Q0406/80.


Assuntos
Aborto Espontâneo/sangue , Endoglina/sangue , Hormônios Gastrointestinais/sangue , Fator de Crescimento Placentário/sangue , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/sangue , Fator de Crescimento do Endotélio Vascular Derivado de Glândula Endócrina/sangue , Adulto , Biomarcadores/sangue , Feminino , Humanos , Gravidez , Primeiro Trimestre da Gravidez/sangue , Estudos Prospectivos
17.
Public Health ; 134: 18-25, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26927823

RESUMO

OBJECTIVES: What explains increases in BMI (and obesity) over time and across countries? Although many microeconomic forces are likely explanations, increasingly scholars are arguing that macroeconomic forces such as market liberalism and globalization are root causes of the obesity epidemic. The purpose of this paper is to examine the impact of economic freedom on obesity conditional on the level of income and other factors. STUDY DESIGN: We use an unbalanced pooled cross section of up to 135 countries for 1995 and 2000-2009. METHODS: Our statistical model specifications include pooled OLS and fixed effects. RESULTS: First, we find that controlling for fixed effects siphons off much of the relationship previously documented between economic freedom and BMI. Second, economic freedom is associated with slightly higher BMIs but only for men in developing nations. Lastly, we show that economic freedom increases life expectancy for both men and women in developing countries. CONCLUSION: Therefore, policies aimed at reducing obesity that limit economic liberalism may come at the expense of life expectancy in the developing world.


Assuntos
Índice de Massa Corporal , Países em Desenvolvimento/estatística & dados numéricos , Liberdade , Renda/estatística & dados numéricos , Obesidade/epidemiologia , Feminino , Humanos , Expectativa de Vida , Masculino , Modelos Estatísticos , Política
18.
Nat Commun ; 15(1): 2003, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38443359

RESUMO

Airborne transmission of SARS-CoV-2 aerosol remains contentious. Importantly, whether cough or breath-generated bioaerosols can harbor viable and replicating virus remains largely unclarified. We performed size-fractionated aerosol sampling (Andersen cascade impactor) and evaluated viral culturability in human cell lines (infectiousness), viral genetics, and host immunity in ambulatory participants with COVID-19. Sixty-one percent (27/44) and 50% (22/44) of participants emitted variant-specific culture-positive aerosols <10µm and <5µm, respectively, for up to 9 days after symptom onset. Aerosol culturability is significantly associated with lower neutralizing antibody titers, and suppression of transcriptomic pathways related to innate immunity and the humoral response. A nasopharyngeal Ct <17 rules-in ~40% of aerosol culture-positives and identifies those who are probably highly infectious. A parsimonious three transcript blood-based biosignature is highly predictive of infectious aerosol generation (PPV > 95%). There is considerable heterogeneity in potential infectiousness i.e., only 29% of participants were probably highly infectious (produced culture-positive aerosols <5µm at ~6 days after symptom onset). These data, which comprehensively confirm variant-specific culturable SARS-CoV-2 in aerosol, inform the targeting of transmission-related interventions and public health containment strategies emphasizing improved ventilation.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Cinética , Aerossóis e Gotículas Respiratórios
19.
J Virol ; 86(22): 12013-24, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22933291

RESUMO

HLA-B*81:01 and HLA-B*39:10 alleles have been associated with viremic control in HIV-1 subtype C infection. Both alleles restrict the TL9 epitope in p24 Gag, and cytotoxic-T-lymphocyte (CTL)-mediated escape mutations in this epitope have been associated with an in vitro fitness cost to the virus. We investigated the timing and impact of mutations in the TL9 epitope on disease progression in five B*81:01- and two B*39:10-positive subtype C-infected individuals. Whereas both B*39:10 participants sampled at 2 months postinfection had viruses with mutations in the TL9 epitope, in three of the five (3/5) B*81:01 participants, TL9 escape mutations were only detected 10 months after infection, taking an additional 10 to 15 months to reach fixation. In the two remaining B*81:01 individuals, one carried a TL9 escape variant at 2 weeks postinfection, whereas no escape mutations were detected in the virus from the other participant for up to 33 months postinfection, despite CTL targeting of the epitope. In all participants, escape mutations in TL9 were linked to coevolving residues in the region of Gag known to be associated with host tropism. Late escape in TL9, together with coevolution of putative compensatory mutations, coincided with a spontaneous increase in viral loads in two individuals who were otherwise controlling the infection. These results provide in vivo evidence of the detrimental impact of B*81:01-mediated viral evolution, in a single Gag p24 epitope, on the control of viremia.


Assuntos
Proteína do Núcleo p24 do HIV/genética , Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV-1/metabolismo , Antígenos HLA-B/genética , Alelos , Separação Celular , Progressão da Doença , Epitopos/química , Feminino , Citometria de Fluxo , Genótipo , Infecções por HIV/genética , Humanos , Interferon gama/metabolismo , Cinética , Estudos Longitudinais , Dados de Sequência Molecular , Mutação , África do Sul , Fatores de Tempo , Receptor Toll-Like 9/genética
20.
BMJ Mil Health ; 169(6): 529-534, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-35078940

RESUMO

INTRODUCTION: At the start of the COVID-19 pandemic, individuals with pre-existing mental health difficulties were thought to be vulnerable to mental health deterioration due to the emerging threat and the actions taken to control infection rates. Yet, there remained a paucity of research investigating changes in veteran well-being, a population facing higher rates of mental health difficulties compared with the general public. This longitudinal study aimed to investigate the mental health and well-being of UK veterans with pre-existing mental health difficulties at two time points during the COVID-19 pandemic. METHODS: UK treatment-seeking veterans (N=121) completed an online survey administered towards the end of the first UK lockdown in June 2020 and 1 year later. Data were gathered on sociodemographic characteristics as well as psychometric measures of post-traumatic stress disorder (PTSD), common mental disorders (CMDs), anger difficulties and alcohol misuse. RESULTS: The proportion of veterans meeting criteria of PTSD, anger and alcohol misuse remained similar across the two time points, while significantly fewer veterans met criteria for CMDs 1 year later. A notable proportion of the sample reported challenges in attending mental and physical health appointments, which was positively associated with not working and negatively associated with more COVID-19-related stressors. CONCLUSIONS: These findings suggest that, to date, veterans with pre-existing mental health difficulties appear to demonstrate resilience as the COVID-19 pandemic progressed. However, as the pandemic continued, veterans faced significantly more COVID-19-related stressors, less social support, as well as difficulties attending health appointments.


Assuntos
Alcoolismo , COVID-19 , Veteranos , Humanos , Veteranos/psicologia , Saúde Mental , Pandemias , Estudos Longitudinais , Alcoolismo/psicologia , COVID-19/epidemiologia , Controle de Doenças Transmissíveis , Reino Unido/epidemiologia
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