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1.
Proc Biol Sci ; 288(1956): 20211260, 2021 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-34375552

RESUMO

The occurrence and proliferation of reef-forming corals is of vast importance in terms of the biodiversity they support and the ecosystem services they provide. The complex three-dimensional structures engineered by corals are comprised of both live and dead coral, and the function, growth and stability of these systems will depend on the ratio of both. To model how the ratio of live : dead coral may change, the 'Goldilocks Principle' can be used, where organisms will only flourish if conditions are 'just right'. With data from particle imaging velocimetry and numerical smooth particle hydrodynamic modelling with two simple rules, we demonstrate how this principle can be applied to a model reef system, and how corals are effectively optimizing their own local flow requirements through habitat engineering. Building on advances here, these approaches can be used in conjunction with numerical modelling to investigate the growth and mortality of biodiversity supporting framework in present-day and future coral reef structures.


Assuntos
Antozoários , Animais , Biodiversidade , Recifes de Corais , Ecossistema , Hidrodinâmica
2.
Phys Rev Lett ; 126(7): 071103, 2021 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-33666466

RESUMO

ANITA's fourth long-duration balloon flight in 2016 detected 29 cosmic-ray (CR)-like events on a background of 0.37_{-0.17}^{+0.27} anthropogenic events. CRs are mainly seen in reflection off the Antarctic ice sheets, creating a phase-inverted waveform polarity. However, four of the below-horizon CR-like events show anomalous noninverted polarity, a p=5.3×10^{-4} chance if due to background. All anomalous events are from locations near the horizon; ANITA-IV observed no steeply upcoming anomalous events similar to the two such events seen in prior flights.

3.
Clin Radiol ; 76(8): 628.e1-628.e7, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33879320

RESUMO

AIM: To compare ejection fraction estimated by tricuspid annular plane systolic excursion (TAPSE) using cardiac computed tomography (CT) and cardiac magnetic resonance imaging (MRI) to the non-invasive reference standard, volumetric quantification of right ventricular ejection fraction (RVEF) by cardiac magnetic resonance imaging (MRI). MATERIALS AND METHODS: Thirty-one patients, who had undergone functional cardiac CT angiogram and cardiac MRI within 12 months, were evaluated retrospectively. Right ventricular (RV) volumes were processed using automated cardiac analysis software for CT, and manually processed by Simpson's method for MRI. MR-TAPSE was defined as the difference in length between two separate reference lines drawn at end diastole and end systole from the lateral tricuspid annulus to the right ventricular apex measured on four-chamber CINE images. CT-TAPSE was determined in an analogous manner on four-chamber reformatted images. RESULTS: MR-TAPSE correlated moderately with MR-RVEF, (r=0.57, p<0.001). CT-TAPSE was found to correlate moderately well with MR-RVEF (r=0.58, p<0.001) and CT-RVEF (r=0.63, p<0.001). Bland-Altman analysis repeated with various multiplication factors for CT-TAPSE and MR-RVEF, determined a multiplication factor of 2.7 resulted in the lowest bias (0.74%). CONCLUSION: CT-TAPSE is an easily obtainable parameter of RV function and is correlated with CT-RVEF and MR-RVEF. It can function as a quick check to rapidly validate CT right volumetry and estimate MR-RVEF.


Assuntos
Ecocardiografia/métodos , Imageamento por Ressonância Magnética/métodos , Tomografia Computadorizada por Raios X/métodos , Disfunção Ventricular Direita/diagnóstico por imagem , Função Ventricular Direita/fisiologia , Feminino , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos , Disfunção Ventricular Direita/fisiopatologia
4.
Phys Rev Lett ; 121(16): 161102, 2018 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-30387639

RESUMO

We report on an upward traveling, radio-detected cosmic-ray-like impulsive event with characteristics closely matching an extensive air shower. This event, observed in the third flight of the Antarctic Impulsive Transient Antenna (ANITA), a NASA-sponsored long-duration balloon payload, is consistent with a similar event reported in a previous flight. These events could be produced by the atmospheric decay of an upward-propagating τ lepton produced by a ν_{τ} interaction, although their relatively steep arrival angles create tension with the standard model neutrino cross section. Each of the two events have a posteriori background estimates of ≲10^{-2} events. If these are generated by τ-lepton decay, then either the charged-current ν_{τ} cross section is suppressed at EeV energies, or the events arise at moments when the peak flux of a transient neutrino source was much larger than the typical expected cosmogenic background neutrinos.

5.
Coral Reefs ; 37(1): 253-266, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-31258386

RESUMO

This study demonstrates how cold-water coral morphology and habitat distribution are shaped by local hydrodynamics, using high-definition video from Tisler Reef, an inshore reef in Norway. A total of 334 video frames collected on the north-west (NW) and south-east (SE) side of the reef were investigated for Lophelia pertusa coral cover and morphology and for the cover of the associated sponges Mycale lingua and Geodia sp. Our results showed that the SE side was a better habitat for L. pertusa (including live and dead colonies). Low cover of Geodia sp. was found on both sides of Tisler Reef. In contrast, Mycale lingua had higher percentage cover, especially on the NW side of the reef. Bush-shaped colonies of L. pertusa with elongated branches were the most abundant coral morphology on Tisler Reef. The highest abundance and density of this morphology were found on the SE side of the reef, while a higher proportion of cauliflower-shaped corals with short branches were found on the NW side. The proportion of very small L. pertusa colonies was also significantly higher on the SE side of the reef. The patterns in coral spatial distribution and morphology were related to local hydrodynamics-there were more frequent periods of downwelling currents on the SE side-and to the availability of suitable settling substrates. These factors make the SE region of Tisler Reef more suitable for coral growth. Understanding the impact of local hydrodynamics on the spatial extent and morphology of coral, and their relation to associated organisms such as sponges, is key to understanding the past and future development of the reef.

6.
HIV Med ; 18(5): 321-331, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-27649852

RESUMO

OBJECTIVES: Human papillomavirus (HPV)-associated cancers disproportionately affect those infected with HIV despite effective combination antiretroviral therapy (cART). The primary aim of this study was to quantify HPV16 and HPV52 E6-specific interferon (IFN)-γ enzyme-linked immunospot (ELISPOT) T-cell responses, a correlate of protective immunity, in the first year following cART initiation and subsequently in those patients with suboptimal (sIR) and optimal (oIR) immune reconstitution. METHODS: Ninety-four HIV-infected patients were recruited to the study; a longitudinal cohort of patients recruited just prior to commencing cART and followed up for 48 weeks (n = 27), and a cross-sectional cohort (n = 67) consisting of patients with sIR (CD4 T-cell count < 350 cells/µL) and oIR (CD4 T-cell count > 500 cells/µL) after a minimum of 2 years on cART. Controls (n = 29) consisted of HIV-negative individuals. IFN-γ ELISPOT responses against HPV16 and HPV52 E6 were correlated to clinical characteristics, anal and oral HPV carriage, T-cell maturational subsets, markers of activation, senescence and T-regulatory cells. RESULTS: HPV16 and HPV52 E6-specific T-cell responses were detected in only one of 27 patients (3.7%) during the initial phase of immune recovery. After at least 2 years of cART, those who achieved oIR had significantly higher E6-specific responses (9 of 34; 26.5%) compared with those with sIR (2 of 32; 6.3%) (P = 0.029). Apart from higher CD4 T-cell counts and lower CD4 T-cell activation, no other immunological correlates were associated with the detection of HPV16 and HPV52 E6-specific responses. CONCLUSIONS: HPV16 and HPV52 E6-specific IFN-γ T-cell responses, a correlate of protective immunity, were detected more frequently among HIV-infected patients who achieved optimal immune recovery on cART (26.5%) compared with those with suboptimal recovery (6.3%).


Assuntos
Antirretrovirais/uso terapêutico , Terapia Antirretroviral de Alta Atividade , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Proteínas Oncogênicas Virais/imunologia , Papillomaviridae/imunologia , Infecções por Papillomavirus/imunologia , Adulto , Estudos Transversais , ELISPOT , Feminino , Genótipo , Humanos , Interferon gama/metabolismo , Leucócitos Mononucleares/imunologia , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade
7.
Coral Reefs ; 36(1): 255-268, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-32269410

RESUMO

Cold-water corals form substantial biogenic habitats on continental shelves and in deep-sea areas with topographic highs, such as banks and seamounts. In the Atlantic, many reef and mound complexes are engineered by Lophelia pertusa, the dominant framework-forming coral. In this study, a variety of mapping approaches were used at a range of scales to map the distribution of both cold-water coral habitats and individual coral colonies at the Mingulay Reef Complex (west Scotland). The new ArcGIS-based British Geological Survey (BGS) seabed mapping toolbox semi-automatically delineated over 500 Lophelia reef 'mini-mounds' from bathymetry data with 2-m resolution. The morphometric and acoustic characteristics of the mini-mounds were also automatically quantified and captured using this toolbox. Coral presence data were derived from high-definition remotely operated vehicle (ROV) records and high-resolution microbathymetry collected by a ROV-mounted multibeam echosounder. With a resolution of 0.35 × 0.35 m, the microbathymetry covers 0.6 km2 in the centre of the study area and allowed identification of individual live coral colonies in acoustic data for the first time. Maximum water depth, maximum rugosity, mean rugosity, bathymetric positioning index and maximum current speed were identified as the environmental variables that contributed most to the prediction of live coral presence. These variables were used to create a predictive map of the likelihood of presence of live cold-water coral colonies in the area of the Mingulay Reef Complex covered by the 2-m resolution data set. Predictive maps of live corals across the reef will be especially valuable for future long-term monitoring surveys, including those needed to understand the impacts of global climate change. This is the first study using the newly developed BGS seabed mapping toolbox and an ROV-based microbathymetric grid to explore the environmental variables that control coral growth on cold-water coral reefs.

8.
J Fish Biol ; 89(2): 1473-81, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27350418

RESUMO

Highly localized concentrations of elasmobranch egg capsules of the deep-water skate Bathyraja richardsoni were discovered during the first remotely operated vehicle (ROV) survey of the Hebrides Terrace Seamount in the Rockall Trough, north-east Atlantic Ocean. Conductivity-temperature-depth profiling indicated that the eggs were bathed in a specific environmental niche of well-oxygenated waters between 4·20 and 4·55° C, and salinity 34·95-35·06, on a coarse to fine-grained sandy seabed on the seamount's eastern flank, whereas a second type of egg capsule (possibly belonging to the skate Dipturus sp.) was recorded exclusively amongst the reef-building stony coral Solenosmilia variabilis. The depths of both egg-laying habitats (1489-1580 m) provide a de facto refuge from fisheries mortality for younger life stages of these skates.


Assuntos
Ecossistema , Óvulo , Rajidae , Animais , Antozoários , Oceano Atlântico , Elasmobrânquios , Feminino , Pesqueiros , Masculino , Oviposição , Salinidade , Água
9.
Proc Biol Sci ; 282(1813): 20150990, 2015 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-26290073

RESUMO

Cold-water corals, such as Lophelia pertusa, are key habitat-forming organisms found throughout the world's oceans to 3000 m deep. The complex three-dimensional framework made by these vulnerable marine ecosystems support high biodiversity and commercially important species. Given their importance, a key question is how both the living and the dead framework will fare under projected climate change. Here, we demonstrate that over 12 months L. pertusa can physiologically acclimate to increased CO2, showing sustained net calcification. However, their new skeletal structure changes and exhibits decreased crystallographic and molecular-scale bonding organization. Although physiological acclimatization was evident, we also demonstrate that there is a negative correlation between increasing CO2 levels and breaking strength of exposed framework (approx. 20-30% weaker after 12 months), meaning the exposed bases of reefs will be less effective 'load-bearers', and will become more susceptible to bioerosion and mechanical damage by 2100.


Assuntos
Antozoários/fisiologia , Mudança Climática , Água do Mar/química , Aclimatação , Animais , Antozoários/crescimento & desenvolvimento , Oceano Atlântico , Calcificação Fisiológica , Dióxido de Carbono/metabolismo , Recifes de Corais , Concentração de Íons de Hidrogênio , Oceanos e Mares , Respiração , Escócia , Temperatura
10.
Mol Ecol ; 24(10): 2379-91, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25846956

RESUMO

Host shifts are a key mechanism of parasite evolution and responsible for the emergence of many economically important pathogens. Varroa destructor has been a major factor in global honeybee (Apis mellifera) declines since shifting hosts from the Asian honeybee (Apis cerana) > 50 years ago. Until recently, only two haplotypes of V. destructor (Korea and Japan) had successfully host shifted to A. mellifera. In 2008, the sister species V. jacobsoni was found for the first time parasitizing A. mellifera in Papua New Guinea (PNG). This recent host shift presents a serious threat to world apiculture but also provides the opportunity to examine host shifting in this system. We used 12 microsatellites to compare genetic variation of V. jacobsoni on A. mellifera in PNG with mites on A. cerana in both PNG and surrounding regions. We identified two distinct lineages of V. jacobsoni reproducing on A. mellifera in PNG. Our analysis indicated independent host shift events have occurred through small numbers of mites shifting from local A. cerana populations. Additional lineages were found in the neighbouring Papua and Solomon Islands that had partially host shifted to A. mellifera, that is producing immature offspring on drone brood only. These mites were likely in transition to full colonization of A. mellifera. Significant population structure between mites on the different hosts suggested host shifted V. jacobsoni populations may not still reproduce on A. cerana, although limited gene flow may exist. Our studies provide further insight into parasite host shift evolution and help characterize this new Varroa mite threat to A. mellifera worldwide.


Assuntos
Abelhas/parasitologia , Variação Genética , Especificidade de Hospedeiro , Varroidae/genética , Animais , Teorema de Bayes , Fluxo Gênico , Genética Populacional , Haplótipos , Interações Hospedeiro-Parasita/genética , Repetições de Microssatélites , Modelos Genéticos , Papua Nova Guiné , Análise de Sequência de DNA
11.
Epidemiol Infect ; 143(16): 3459-67, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25907106

RESUMO

The incidence of recreational water-associated outbreaks in the United States has significantly increased, driven, at least in part, by outbreaks both caused by Cryptosporidium and associated with treated recreational water venues. Because of the parasite's extreme chlorine tolerance, transmission can occur even in well-maintained treated recreational water venues (e.g. pools) and a focal cryptosporidiosis outbreak can evolve into a community-wide outbreak associated with multiple recreational water venues and settings (e.g. childcare facilities). In August 2004 in Auglaize County, Ohio, multiple cryptosporidiosis cases were identified and anecdotally linked to pool A. Within 5 days of the first case being reported, pool A was hyperchlorinated to achieve 99·9% Cryptosporidium inactivition. A case-control study was launched to epidemiologically ascertain the outbreak source 11 days later. A total of 150 confirmed and probable cases were identified; the temporal distribution of illness onset was peaked, indicating a point-source exposure. Cryptosporidiosis was significantly associated with swimming in pool A (matched odds ratio 121·7, 95% confidence interval 27·4-∞) but not with another venue or setting. The findings of this investigation suggest that proactive implementation of control measures, when increased Cryptosporidium transmission is detected but before an outbreak source is epidemiologically ascertained, might prevent a focal cryptosporidiosis outbreak from evolving into a community-wide outbreak.


Assuntos
Criptosporidiose/epidemiologia , Criptosporidiose/prevenção & controle , Cryptosporidium/isolamento & purificação , Transmissão de Doença Infecciosa/prevenção & controle , Água Doce/parasitologia , Controle de Infecções/métodos , Piscinas , Adolescente , Adulto , Estudos de Casos e Controles , Criança , Pré-Escolar , Criptosporidiose/transmissão , Feminino , Halogenação , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Ohio/epidemiologia , Adulto Jovem
13.
J Invertebr Pathol ; 118: 71-4, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24650855

RESUMO

This study has characterised a novel serotype of Sacbrood virus (SBV) infecting Apis mellifera in New Guinea that has emerged in the presence of the introduced European and Asian serotypes, which infect A. mellifera and Apis cerana, respectively. The New Guinea serotype appears to have evolved through mutation of the European serotype with no evidence of recombination between known strains, although recombination was detected in other SBV isolates from Asia. SBV was also confirmed for the first time causing disease in Apis dorsata (giant Asian honeybee) in Indonesia and found to be infected by the Asian serotype.


Assuntos
Abelhas/virologia , Vírus de RNA/genética , RNA Viral/análise , Animais , Sequência de Bases , Dados de Sequência Molecular , Nova Guiné , Filogenia , Sorogrupo
14.
BJOG ; 120(10): 1192-9, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23718253

RESUMO

OBJECTIVE: The phenotype of the antioxidant and pro-angiogenic protein haptoglobin (Hp) predicts cardiovascular disease risk and treatment response to antioxidant vitamins in individuals with diabetes. Our objective was to determine whether Hp phenotype influences pre-eclampsia risk, or the efficacy of vitamins C and E in preventing pre-eclampsia, in women with type-1 diabetes. DESIGN: This is a secondary analysis of a randomised controlled trial in which women with diabetes received daily vitamins C and E, or placebo, from 8 to 22 weeks of gestation until delivery. SETTING: Twenty-five antenatal metabolic clinics across the UK (in north-west England, Scotland, and Northern Ireland). POPULATION: Pregnant women with type-1 diabetes. METHODS: Hp phenotype was determined in white women who completed the study and had plasma samples available (n = 685). MAIN OUTCOME MEASURE: Pre-eclampsia. RESULTS: Compared with Hp 2-1, Hp 1-1 (OR 0.59, 95% CI 0.30-1.16) and Hp 2-2 (OR 0.93, 95% CI 0.60-1.45) were not associated with significantly decreased pre-eclampsia risk after adjusting for treatment group and HbA1c at randomisation. Our study was not powered to detect an interaction between Hp phenotype and treatment response; however, our preliminary analysis suggests that vitamins C and E did not prevent pre-eclampsia in women of any Hp phenotype (Hp 1-1, OR 0.77, 95% CI 0.22-2.71; Hp 2-1, OR 0.81, 95% CI 0.46-1.43; Hp 2-2, 0.67, 95% CI 0.34-1.33), after adjusting for HbA1c at randomisation. CONCLUSIONS: The Hp phenotype did not significantly affect pre-eclampsia risk in women with type-1 diabetes.


Assuntos
Antioxidantes/uso terapêutico , Ácido Ascórbico/uso terapêutico , Diabetes Mellitus Tipo 1/complicações , Haptoglobinas/metabolismo , Pré-Eclâmpsia/sangue , Pré-Eclâmpsia/prevenção & controle , Gravidez em Diabéticas/sangue , Vitamina E/uso terapêutico , Antioxidantes/metabolismo , Feminino , Haptoglobinas/química , Humanos , Razão de Chances , Estresse Oxidativo/efeitos dos fármacos , Fenótipo , Pré-Eclâmpsia/etiologia , Gravidez , Fatores de Risco
15.
BJOG ; 120(10): 1183-91, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23331974

RESUMO

OBJECTIVE: To determine if change in maternal angiogenic biomarkers between the first and second trimesters predicts pre-eclampsia in low-risk nulliparous women. DESIGN: A nested case-control study of change in maternal plasma soluble Flt-1 (sFlt-1), soluble endoglin (sEng) and placenta growth factor (PlGF). We studied 158 pregnancies complicated by pre-eclampsia and 468 normotensive nonproteinuric controls. SETTING: A multicentre study in 16 academic medical centres in the USA. POPULATION: Low-risk nulliparous women. METHODS: Luminex assays for PlGF, sFlt-1 and sEng performed on maternal EDTA plasma collected at 9-12, 15-18 and 23-26 weeks of gestation. Rate of change of analyte between first and either early or late second trimester was calculated with and without adjustment for baseline clinical characteristics. MAIN OUTCOME MEASURES: Change in PlGF, sFlt-1 and sEng. RESULTS: Rates of change of PlGF, sEng and sFlt-1 between first and either early or late second trimesters were significantly different in women who developed pre-eclampsia, severe pre-eclampsia or early-onset pre-eclampsia compared with women who remained normotensive. Inclusion of clinical characteristics (race, body mass index and blood pressure at entry) increased sensitivity for detecting severe and particularly early-onset pre-eclampsia but not pre-eclampsia overall. Receiver operating characteristics curves for change from first to early second trimester in sEng, PlGF and sFlt-1 with clinical characteristics had areas under the curve of 0.88, 0.84 and 0.86, respectively, and for early-onset pre-eclampsia with sensitivities of 88% (95% CI 64-99), 77% (95% CI 50-93) and 77% (95% CI 50-93) for 80% specificity, respectively. Similar results were seen in the change from first to late second trimester. CONCLUSION: Change in angiogenic biomarkers between first and early second trimester combined with clinical characteristics has strong utility for predicting early-onset pre-eclampsia.


Assuntos
Antígenos CD/sangue , Pré-Eclâmpsia/sangue , Proteínas da Gravidez/sangue , Primeiro Trimestre da Gravidez/sangue , Segundo Trimestre da Gravidez/sangue , Receptores de Superfície Celular/sangue , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/sangue , Adulto , Biomarcadores/sangue , Pressão Sanguínea , Índice de Massa Corporal , Diagnóstico Precoce , Endoglina , Feminino , Humanos , Estudos Longitudinais , Paridade , Fator de Crescimento Placentário , Pré-Eclâmpsia/diagnóstico , Pré-Eclâmpsia/etnologia , Gravidez , Fatores de Risco , Adulto Jovem
16.
Environ Sci Technol ; 46(15): 8025-34, 2012 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-22788666

RESUMO

In June 2010, the NOAA WP-3D aircraft conducted two survey flights around the Deepwater Horizon (DWH) oil spill. The Gulf oil spill resulted in an isolated source of secondary organic aerosol (SOA) precursors in a relatively clean environment. Measurements of aerosol composition and volatile organic species (VOCs) indicated formation of SOA from intermediate-volatility organic compounds (IVOCs) downwind of the oil spill (Science2011, 331, doi 10.1126/science.1200320). In an effort to better understand formation of SOA in this environment, we present mass spectral characteristics of SOA in the Gulf and of SOA formed in the laboratory from evaporated light crude oil. Compared to urban primary organic aerosol, high-mass-resolution analysis of the background-subtracted SOA spectra in the Gulf (for short, "Gulf SOA") showed higher contribution of C(x)H(y)O(+) relative to C(x)H(y)(+) fragments at the same nominal mass. In each transect downwind of the DWH spill site, a gradient in the degree of oxidation of the Gulf SOA was observed: more oxidized SOA (oxygen/carbon = O/C ∼0.4) was observed in the area impacted by fresher oil; less oxidized SOA (O/C ∼0.3), with contribution from fragments with a hydrocarbon backbone, was found in a broader region of more-aged surface oil. Furthermore, in the plumes originating from the more-aged oil, contribution of oxygenated fragments to SOA decreased with downwind distance. Despite differences between experimental conditions in the laboratory and the ambient environment, mass spectra of SOA formed from gas-phase oxidation of crude oil by OH radicals in a smog chamber and a flow tube reactor strongly resembled the mass spectra of Gulf SOA (r(2) > 0.94). Processes that led to the observed Gulf SOA characteristics are also likely to occur in polluted regions where VOCs and IVOCs are coemitted.


Assuntos
Aerossóis , Poluentes Atmosféricos/análise , Espectrometria de Massas/métodos , Poluição por Petróleo , Compostos Orgânicos Voláteis/análise , Oxirredução
17.
BJOG ; 119(4): 484-92, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22251368

RESUMO

OBJECTIVE: To examine the relationship between hyperuricaemia, haemoconcentration and maternal and fetal outcomes in hypertensive pregnancies. DESIGN: Retrospective analysis of a database of hypertensive pregnancies. SETTING: St George Hospital, a major obstetric unit in Australia. POPULATION: A cohort of 1880 pregnant women without underlying hypertension or renal disease, referred for management of pre-eclampsia or gestational hypertension. METHODS: Demographic, clinical and biochemical data at time of referral and delivery were collected for each pregnancy. Women were grouped according to diagnosis (pre-eclampsia or gestational hypertension) and logistic regression analysis was used to determine the relationship between uric acid, haemoglobin, haematocrit and adverse outcomes; an α level of P < 0.01 was used for statistical significance. MAIN OUTCOME MEASURES: Composites of adverse maternal and fetal outcomes. RESULTS: In women with 'benign' GH (without proteinuria or any other maternal clinical feature of pre-eclampsia) gestation-corrected hyperuricaemia was associated with increased risk of a small-for-gestational-age infant (OR 2.5; 95% CI 1.3-4.8) and prematurity (OR 3.2; 95% CI 1.4-7.2), but not with adverse maternal outcome. In the whole cohort of hypertensive pregnant women (those with pre-eclampsia or gestational hypertension) the risk of adverse maternal outcome (OR 2.0; 95% CI 1.6-2.4) and adverse fetal outcome (OR 1.8; 95% CI 1.5-2.1) increased with increasing concentration of uric acid. Hyperuricaemia corrected for gestation provided additional strength to these associations. Haemoglobin and haematocrit were not associated with adverse pregnancy outcome. CONCLUSIONS: Hyperuricaemia in hypertensive pregnancy remains an important finding because it identifies women at increased risk of adverse maternal and particularly fetal outcome; the latter, even in women with gestational hypertension without any other feature of pre-eclampsia.


Assuntos
Antioxidantes/metabolismo , Hipertensão Induzida pela Gravidez/sangue , Hiperuricemia/sangue , Ácido Úrico/sangue , Adulto , Algoritmos , Austrália/epidemiologia , Biomarcadores/sangue , Estudos de Coortes , Feminino , Hematócrito , Hemoglobinas , Humanos , Hipertensão Induzida pela Gravidez/diagnóstico , Hipertensão Induzida pela Gravidez/epidemiologia , Hiperuricemia/complicações , Hiperuricemia/diagnóstico , Hiperuricemia/epidemiologia , Recém-Nascido , Recém-Nascido Prematuro , Recém-Nascido Pequeno para a Idade Gestacional/sangue , Modelos Logísticos , Pré-Eclâmpsia/sangue , Gravidez , Resultado da Gravidez , Nascimento Prematuro/sangue , Nascimento Prematuro/etiologia , Prevalência , Estudos Retrospectivos , Medição de Risco , Fatores de Risco
18.
Curr Opin Cell Biol ; 5(2): 201-6, 1993 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8507492

RESUMO

DNA replication is coupled to cell cycle progression at a major regulatory point in the G1 phase of the cell cycle. At this point, the catalytic subunit of a protein kinase (encoded by the CDC28 gene in budding yeast or the homologous CDC2 gene in other eukaryotes) is activated by binding to a positively acting regulatory subunit, a cyclin. Recent research has revealed evidence for two pathways that might connect these kinases to the proteins that replicate DNA: activation of an essential replication factor, or removal of the block that limits genome duplication to once per cell cycle.


Assuntos
Replicação do DNA/fisiologia , Proteínas Quinases/fisiologia , Ciclo Celular , Ciclinas , Células Eucarióticas
19.
Nat Med ; 4(5): 575-80, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9585231

RESUMO

The cyclin-dependent kinase inhibitor p27Kip1 controls cell proliferation in response to normal mitogenic stimuli. We show here that p27Kip1 also safeguards against excessive cell proliferation in specific pathophysiologic settings. We used experimental glomerulonephritis as a paradigm for immune mediated inflammation and ureteral obstruction as a model for non-immune mediated inflammation. Renal function was substantially decreased in nephritic p27-/- mice compared with control mice, and this was associated with increased glomerular cell proliferation, apoptosis and matrix protein accumulation. Tubular epithelial cell proliferation and apoptosis was also increased in p27-/- mice following ureteral obstruction. p27Kip1 may have a general role in protecting cells and tissues from inflammatory injury.


Assuntos
Quinases relacionadas a CDC2 e CDC28 , Proteínas de Ciclo Celular , Glomerulonefrite/fisiopatologia , Proteínas Associadas aos Microtúbulos/deficiência , Proteínas Supressoras de Tumor , Obstrução Ureteral/fisiopatologia , Animais , Apoptose , Divisão Celular , Quinase 2 Dependente de Ciclina , Inibidor de Quinase Dependente de Ciclina p27 , Quinases Ciclina-Dependentes/metabolismo , Rim/imunologia , Testes de Função Renal , Glomérulos Renais/patologia , Túbulos Renais/patologia , Camundongos , Camundongos Mutantes , Proteínas Associadas aos Microtúbulos/genética , Proteínas Serina-Treonina Quinases/metabolismo
20.
Nat Med ; 3(2): 222-5, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9018243

RESUMO

Mutations in certain genes that regulate the cell cycle, such as p16 and p53, are frequently found in human cancers. However, tumor-specific mutations are uncommon in genes encoding cyclin E and the CDK inhibitor p27Kip1, two cell-cycle regulators that are also thought to contribute to tumor progression. It is now known that levels of both cyclin E and p27 can be controlled by posttranscriptional mechanisms, indicating that expression of these proteins can be altered by means other than simply mutation of their respective genes. Thus, changes in p27 and cyclin E protein levels in tumors might be more common than previously anticipated and may be indicators of tumor behavior.


Assuntos
Neoplasias da Mama/genética , Carcinoma Ductal de Mama/genética , Proteínas de Ciclo Celular , Ciclinas/genética , Expressão Gênica , Genes cdc , Proteínas Associadas aos Microtúbulos/genética , Proteínas Supressoras de Tumor , Adulto , Biomarcadores Tumorais , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/mortalidade , Carcinoma Ductal de Mama/patologia , Inibidor de Quinase Dependente de Ciclina p27 , Feminino , Humanos , Prognóstico , Análise de Sobrevida
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