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1.
Sol Phys ; 293(1): 7, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-31997837

RESUMO

We describe a partial filament eruption on 11 December 2011 that demonstrates that the inclusion of mass is an important next step for understanding solar eruptions. Observations from the Solar Terrestrial Relations Observatory-Behind (STEREO-B) and the Solar Dynamics Observatory (SDO) spacecraft were used to remove line-of-sight projection effects in filament motion and correlate the effect of plasma dynamics with the evolution of the filament height. Flux cancellation and nearby flux emergence are shown to have played a role in increasing the height of the filament prior to eruption. The two viewpoints allow the quantitative estimation of a large mass-unloading, the subsequent radial expansion, and the eruption of the filament to be investigated. A 1.8 to 4.1 lower-limit ratio between gravitational and magnetic-tension forces was found. We therefore conclude that following the loss-of-equilibrium of the flux-rope, the radial expansion of the flux-rope was restrained by the filamentary material until 70% of the mass had evacuated the structure through mass-unloading. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s11207-017-1224-y) contains supplementary material, which is available to authorised users.

2.
J Int Neuropsychol Soc ; 20(9): 909-19, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25171131

RESUMO

The effect of low birth weight on children's development has been documented for a range of neurocognitive outcomes. However, few previous studies have examined the effect of birth weight variability within the normal range on children's neuropsychological development. The current study examined birth weight variation amongst children weighing ≥2500 g in relation to their language, executive functioning (EF), and theory of mind (ToM), and specified a developmental pathway in which birth weight was hypothesized to be associated with children's EF and ToM through their intermediary language skills. The current study used a prospective community birth cohort of 468 children. Families were recruited when children were newborns and followed up every 18 months until children were age 4.5. Language was assessed at age 3 using a standardized measure of receptive vocabulary (PPVT), and EF and ToM were measured at age 4.5 using previously validated and developmentally appropriate tasks. After controlling for potential confounding variables (family income, parent education, gestational age), birth weight within the normal range was associated with language ability at age 3 (ß=.17; p=.012); and the effect of birth weight on both EF (z=2.09; p=.03) and ToM (z=2.07; p=.03) at age 4.5 operated indirectly through their language ability at age 3. Our findings indicate that the effects of birth weight on child neurocognition extend into the normal range of birth weight, and specific developmental mechanisms may link these skills over time.


Assuntos
Peso ao Nascer/fisiologia , Desenvolvimento Infantil/fisiologia , Função Executiva/fisiologia , Idioma , Teoria da Mente/fisiologia , Fatores Etários , Pré-Escolar , Feminino , Idade Gestacional , Humanos , Lactente , Recém-Nascido , Estudos Longitudinais , Masculino , Testes Neuropsicológicos
3.
Epidemiol Infect ; 141(1): 36-44, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22404843

RESUMO

To identify which medications were most commonly taken by non-pregnancy-related listeriosis patients prior to illness, we compared the medications reported by 512 cases identified via national surveillance in England between 2007 and 2009 with national prescription data, using British National Formulary (BNF) coding. Relative risks and corresponding confidence intervals were calculated, as appropriate, for BNF chapters and sections. Among listeriosis cases, the rates for cytotoxic drugs, drugs affecting the immune response and corticosteroids were significantly higher than for other medications. However, interactions between medications and how medications might confound or be confounded by concurrent medical conditions need to be investigated further. Nevertheless our findings suggest that targeting food-safety advice to prevent this foodborne disease in certain treatment groups is warranted.


Assuntos
Uso de Medicamentos/estatística & dados numéricos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Listeriose/induzido quimicamente , Listeriose/epidemiologia , Adulto , Idoso , Inglaterra , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
4.
Science ; 372(6543): 711-715, 2021 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-33927054

RESUMO

Lightning increases the atmosphere's ability to cleanse itself by producing nitric oxide (NO), leading to atmospheric chemistry that forms ozone (O3) and the atmosphere's primary oxidant, the hydroxyl radical (OH). Our analysis of a 2012 airborne study of deep convection and chemistry demonstrates that lightning also directly generates the oxidants OH and the hydroperoxyl radical (HO2). Extreme amounts of OH and HO2 were discovered and linked to visible flashes occurring in front of the aircraft and to subvisible discharges in electrified anvil regions. This enhanced OH and HO2 is orders of magnitude greater than any previous atmospheric observation. Lightning-generated OH in all storms happening at the same time globally can be responsible for a highly uncertain, but substantial, 2 to 16% of global atmospheric OH oxidation.

5.
Science ; 371(6533): 1038-1041, 2021 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-33674491

RESUMO

Spectroscopy of transiting exoplanets can be used to investigate their atmospheric properties and habitability. Combining radial velocity (RV) and transit data provides additional information on exoplanet physical properties. We detect a transiting rocky planet with an orbital period of 1.467 days around the nearby red dwarf star Gliese 486. The planet Gliese 486 b is 2.81 Earth masses and 1.31 Earth radii, with uncertainties of 5%, as determined from RV data and photometric light curves. The host star is at a distance of ~8.1 parsecs, has a J-band magnitude of ~7.2, and is observable from both hemispheres of Earth. On the basis of these properties and the planet's short orbital period and high equilibrium temperature, we show that this terrestrial planet is suitable for emission and transit spectroscopy.

6.
Ann R Coll Surg Engl ; 100(6): 464-474, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29962301

RESUMO

Introduction Metropolitan Police data, and those from the emergency department at a London major trauma centre show a resurgence in gun crime. The aim of this study was to collect data on all gunshot injuries over a seven-year period at South-East London's trauma hub. Materials and methods This was a retrospective observational study of all gunshot injuries between 1 January 2010 and 31 December 2016 at a London major trauma centre. Information regarding patient demographics, morbidity and mortality was collected. Data from the English indices of multiple deprivation were reviewed in relation to shooting locations and socioeconomic status in South-East London. Results A total of 182 patients from 939,331 emergency admissions presented with firearm injuries. Males comprised 178 (97.8%) victims and 124 (68.1%) were documented as being Black or Afro-Caribbean. The median age was 22 years. Some 124 (71.7%) victims were shot within a 4 km radius of the hospital. The mean indices of multiple deprivation decile ranking in shooting locations compared with non-shooting locations was 2.6 (± 0.1384) and 3.8 (± 0.1149), respectively. A total of 122 (67.0%) patients underwent specialist operative intervention and 111 (61.0%) suffered only superficial or musculoskeletal injuries. Six patients required emergency thoracotomies; three (50.0%) survived to discharge. The median length of stay was 4 days (interquartile range 2-9 days) and 35 (24.0%) were admitted to intensive care. Ten (5.5%) patients died. Discussion and conclusion Firearms injuries are increasing and place a significant burden on hospital resources. Care provided to gunshot victims has improved as a result of recent trauma management initiatives at South-East London's major trauma centre.


Assuntos
Saúde da População Urbana/tendências , Ferimentos por Arma de Fogo/epidemiologia , Adolescente , Adulto , Criança , Feminino , Humanos , Tempo de Internação/estatística & dados numéricos , Modelos Logísticos , Londres/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores Socioeconômicos , Centros de Traumatologia , Saúde da População Urbana/estatística & dados numéricos , Ferimentos por Arma de Fogo/diagnóstico , Ferimentos por Arma de Fogo/etiologia , Ferimentos por Arma de Fogo/terapia , Adulto Jovem
7.
Matrix Biol ; 16(8): 497-505, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9550266

RESUMO

Collagen IX, a structural component of the extracellular matrix of connective tissues, is synthesized as long and short forms which contain or lack, respectively, a 27 kDa non-collagenous (NC) 4 domain at the N-terminus of the alpha 1(IX) chain of the molecule. The long form occurs in cartilage and developing cornea, but not in vitreous, suggesting a specialized function for the NC4 domain, perhaps by interacting with other macromolecules. To test this hypothesis, embryonic chick cartilage was treated with DTSSP, dissociated with bacterial collagenase, and the NC4-containing DTSSP-cross-linked protein complexes examined and purified. Analysis of cartilage extracts using an anti-NC4 antibody, and of purified NC4-containing complexes, identified a predominant NC4 dimer. A naturally-occurring N-terminal fragment of the alpha 1(IX) chain, whose size is equivalent to the NC4-COL3-NC3 domains of the chain, was identified. Association of collagen IX molecules via NC4 domains and the existence of a cleavage site close to the NC3 domain of the molecule are likely to be of primary importance in the growth and remodeling processes of cartilage, in health and disease.


Assuntos
Cartilagem/química , Colágeno/química , Colágeno/metabolismo , Estrutura Terciária de Proteína , Animais , Cartilagem/metabolismo , Embrião de Galinha , Colágeno/imunologia , Reagentes de Ligações Cruzadas/metabolismo , Dimerização , Soros Imunes/biossíntese , Soros Imunes/metabolismo , Peso Molecular , Succinimidas/farmacologia
8.
Gene ; 174(1): 135-43, 1996 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-8863740

RESUMO

The zincins are a superfamily of structurally-related Zn(2+)-binding metallopeptidases which play a major role in a wide range of biological processes including pattern formation, growth factor activation and extracellular matrix synthesis and degradation. In this paper we report the identification and complete primary structure of a novel 33 kDa protein which contains the zinc-binding HEXXH motif found in the zincin superfamily. We have named this novel protein PRSM1 (PRoteaSe, Metallo, number 1). The gene was identified by the immunoscreening of a human placental cDNA library using polyclonal antibodies raised to the 70 kDa human matrix metalloendopeptidase, type III procollagen N-proteinase [Halila, R. and Peltonen, L. (1986) Purification of human procollagen type III N-proteinase from placenta and preparation of antiserum. Biochem. J. 239, 47-52]. The protein is found in placenta and cultured osteosarcoma cells. PRSM1 could share sequence homology with the type III procollagen N-proteinase. The prsm1 gene is represented once in the human genome and is localized on chromosome 16 (q24.3).


Assuntos
Cromossomos Humanos Par 16 , Clonagem Molecular , Metaloendopeptidases/genética , Sequência de Aminoácidos , Sequência de Bases , Mapeamento Cromossômico , Humanos , Dados de Sequência Molecular , Alinhamento de Sequência
9.
Mol Biochem Parasitol ; 22(1): 1-8, 1987 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-3807948

RESUMO

Adult females of the filarial parasite Dipetalonema viteae were radiolabelled using chloroglycoluril and different concentrations of iodine with and without carrier iodide. A detailed quantitative analysis of the distribution of the labelled proteins were carried out using sodium dodecylsulfate and beta-mercaptoethanol to isolate the cuticle after different iodination periods. The highest specific activity was found in the pellet, which comprised the cuticular cortical zone with the highly insoluble epicuticle. However, 50% of the radiolabelled proteins were recovered in the extracts, which contained solubilized material from the somatic compartments and the basal and median zones of the cuticle. The data indicate that the isolation of surface-iodinated antigens of filariae is hampered by the presence of a detergent-insoluble epicuticle. Radiolabelled antigens solubilized by detergents are either proteins from internal somatic or cuticular regions or proteins adsorbed onto the epicuticle.


Assuntos
Antígenos de Helmintos/análise , Dipetalonema/análise , Proteínas/análise , Animais , Antígenos de Superfície/análise , Autorradiografia , Dipetalonema/imunologia , Eletroforese em Gel de Poliacrilamida , Feminino
10.
Pediatrics ; 75(4): 730-6, 1985 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3982905

RESUMO

Twenty-three successive patients with 27 different episodes of sustained atrial flutter were treated with atrial pacing for conversion of the tachyarrhythmia; 15 patients with 16 episodes of atrial flutter underwent intracardiac right atrial pacing and eight patients with 11 episodes of atrial flutter were treated with transesophageal atrial pacing. Ten of sixteen episodes (63%) and eight of 11 episodes (73%) were successfully converted using intracardiac and transesophageal techniques, respectively. Mean flutter cycle length for all 27 episodes was 219 ms (mean heart rate 274 beats per minute); successful pacing conversion cycle length (n = 15) was 72% of the flutter cycle length. Hemodynamic, electrophysiologic, and roentgenographic data were not predictive of conversion by either technique. Induction of localized atrial fibrillation or failure to meet critical pacing criteria may explain pacing failures. Based on this experience, a trial of transesophageal atrial pacing for acute conversion of any episode of atrial flutter in children prior to direct current cardioversion is recommended.


Assuntos
Flutter Atrial/terapia , Estimulação Cardíaca Artificial/métodos , Adolescente , Adulto , Flutter Atrial/etiologia , Criança , Pré-Escolar , Anomalia de Ebstein/complicações , Eletrocardiografia , Esôfago , Estudos de Avaliação como Assunto , Feminino , Ventrículos do Coração/anormalidades , Humanos , Lactente , Masculino , Tetralogia de Fallot/complicações , Transposição dos Grandes Vasos/complicações
11.
Am J Cardiol ; 68(13): 1321-8, 1991 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-1951120

RESUMO

Electrogram pattern recognition by way of morphologic analysis has been proposed as a technique that may improve discrimination of ventricular tachycardia from sinus rhythm by antitachycardia devices. The potential impact that increases in heart rate and sympathetic tone could have on such techniques, however, has not been previously determined. A comparative study was undertaken to quantify possible changes in ventricular electrogram morphology using correlation waveform, area of difference, and amplitude analyses in 6 patients during atrial overdrive pacing at cycle lengths of 600 and 400 ms (group A), in 13 patients during infusions of physiologic doses of epinephrine (group B), and in 20 patients undergoing infusions of isoproterenol (group C). Four patients were in both groups A and B. A bipolar intraventricular template of cardiac depolarization during sinus rhythm at rest was compared with depolarization during subsequent passages of sinus rhythm at rest and subsequently increased heart rate. In 36 of 39 patients, waveform configuration as assessed by correlation waveform analysis remained relatively stable during atrial overdrive pacing, epinephrine infusion, and isoproterenol infusion when compared with sinus rhythm at rest. The correlation value did not fall below 0.950 in any patient. Area of difference values for the same 36 patients changed by an average of 6 and 37% during atrial overdrive pacing at cycle lengths of 600 and 400 ms intervals, respectively, by 3% during epinephrine infusion, and by 17% during isoproterenol infusion. In these same patients, there was an average change in electrogram amplitude of -1% during atrial overdrive pacing at 600 ms, 26% during pacing at 400 ms, -1% during epinephrine infusion, and 12% during isoproterenol infusion.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Estimulação Cardíaca Artificial , Eletrocardiografia/métodos , Frequência Cardíaca/fisiologia , Processamento de Sinais Assistido por Computador , Sistema Nervoso Simpático/fisiologia , Adulto , Epinefrina , Feminino , Humanos , Isoproterenol , Masculino , Pessoa de Meia-Idade
12.
Am J Cardiol ; 52(3): 384-9, 1983 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-6869291

RESUMO

Quantitative studies of left ventricular function using 2-dimensional echocardiography have been limited because of a lack of computerized methods to automatically analyze the echocardiographic images. Previous computer efforts have been directed at digitizing the video output of the 2-D echocardiogram, but this digitizing method has significant limitations. A direct digitization method that produces improvement in signal-to-noise ratio and, subsequently, improved automatic detection of endocardial and epicardial borders, was developed. With definition of these edges, left ventricular global and regional analysis is possible frame by frame so that dynamic changes in cardiac function may be assessed throughout the cardiac cycle. Further technologic advances in 2-D echocardiographic acquisition and image processing should allow computer processing of 2-D echocardiographic data in real time.


Assuntos
Computadores , Ecocardiografia/instrumentação , Humanos
13.
J Clin Pathol ; 39(6): 627-34, 1986 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3013946

RESUMO

Serum and urine steroids were examined in two subjects with trophoblastic disease accompanied by large ovarian theca-lutein cysts and compared with those from 10 patients with trophoblastic disease but without palpable cysts. In the patients without cysts normal values were obtained for serum oestradiol, progesterone, 17 alpha-hydroxyprogesterone and androstenedione, and for urinary total oestrogens, pregnanediol, pregnanetriol, and 17-oxosteroids. Nineteen urinary steroid metabolites, quantified by capillary gas-liquid chromatography, were either within reference limits or marginally raised. In several cases relatively minor increases in serum testosterone and cortisol and urinary free cortisol were observed. In contrast, the subjects with cysts showed pronounced excesses of androgen metabolites, 17 alpha-hydroxypregnenolone, pregnanediol, and pregnanetriol, and both exhibited a similar pattern of unusual additional metabolites. The profiles superficially resembled those seen in 21-hydroxylase deficiency adrenogenital syndrome, but there were important discrepancies reflecting known differences in ovarian and adrenal steroid metabolism. Chemotherapy led to decline of human chorionic gonadotrophin concentrations, regression of the cysts, and return to normal of the steroid profile. Excess steroids in the patients with cysts may have originated in the ovary rather than in the trophoblastic tissue.


Assuntos
Cistos Ovarianos/metabolismo , Esteroides/metabolismo , Neoplasias Trofoblásticas/metabolismo , Neoplasias Uterinas/metabolismo , Adulto , Cromatografia Gasosa , Feminino , Humanos , Masculino , Cistos Ovarianos/complicações , Gravidez , Pregnanodiol/metabolismo , Pregnanotriol/metabolismo , Pregnanolona/análogos & derivados , Pregnanolona/metabolismo , Neoplasias Trofoblásticas/complicações , Neoplasias Uterinas/complicações
14.
J Am Acad Child Adolesc Psychiatry ; 29(1): 60-9, 1990 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2295580

RESUMO

This study investigated factors which were protective to children living in disharmonious homes. The sample was drawn from a representative sample of children aged 9 to 12 who took part in a previous general population study. Semi-structured interviews with both parents were used to assess the quality of the parental marriage. Mothers provided information on children's emotional and behavioral problems and putative protective factors. Fifty-seven families were in the disharmonious marriage group and 62 were in the harmonious marriage group. Putative protective factors, hypothesized to be beneficial for children, were either an aspect of social support or related to children's activities. Data were analyzed using a two-way analysis of variance with parental marriage and the putative protective factor as main effects. A differentiation was made between protective factors which interacted with parental marriage and those that acted independently. Factors which interacted with the quality of parental marriage were children having a relationship with an adult outside the family, an activity for which they received much positive recognition, and good sibling relationships. The parent-child relationship was associated with children's disturbance in both harmonious and disharmonious homes.


Assuntos
Casamento , Transtornos Mentais/prevenção & controle , Logro , Criança , Feminino , Humanos , Masculino , Relações Pais-Filho , Relações entre Irmãos
15.
J Am Acad Child Adolesc Psychiatry ; 28(2): 182-9, 1989 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2925570

RESUMO

Children's reactions to parental quarrels were investigated in a general population sample of children between 9 and 12 years old. One hundred and thirty-nine families participated in the study. Approximately half the children were living in disharmonious families and half were in harmonious families. Mothers and children were interviewed with semistructured interviews to determine how children responded to specific episodes of parental quarrelling. Seventy-one percent of children reported intervening in parental quarrels. A range of other coping strategies was identified: seeking contact with a sibling, confiding in friends, offering comfort to parents after a quarrel, self-blame, seeking information about quarrels, and perceiving beneficial aspects to parental quarrelling. The hypothesis was examined that certain coping strategies would be associated with lower levels of children's behavioral and emotional problems. Only a weak relationship was found between children's intervention in parental quarrels and emotional and behavioral problems. No other coping strategies were found to predict children's disturbance.


Assuntos
Adaptação Psicológica , Casamento , Transtornos Mentais/psicologia , Pais , Criança , Comportamento Infantil , Feminino , Humanos , Masculino , Apoio Social
16.
Fertil Steril ; 63(5): 1005-8, 1995 May.
Artigo em Inglês | MEDLINE | ID: mdl-7720908

RESUMO

OBJECTIVE: To determine whether an inter-relationship exists between endocervical mucus pH, serum androgen levels, and waist to hip (W:H) ratio. SETTING: Donor insemination clinic, University of Sheffield, Jessop Hospital, Sheffield, United Kingdom. PATIENTS: One hundred patients receiving donor insemination. INTERVENTIONS: Waist, hip, height, and weight measurements were recorded for 100 patients receiving donor insemination. At the onset of the LH surge when patients attended for their first insemination, a sample of endocervical mucus and blood was taken. The Insler score of the mucus was recorded and the pH was measured with multirange pH paper. Of the 100 patients studied, 10 cases had an endocervical mucus pH < 6 despite Insler scores of > 10. Serum T, DHEAS, and androstenedione levels were measured in the 10 patients with pH < 6 and in 26 patients selected at random from the 90 patients with pH > or = 6. RESULTS: The W:H ratio was significantly higher in the patients with pH < 6 than pH > or = 6. No significant difference was seen in body mass index between the latter groups. All serum androgen levels were significantly higher in the patients with pH < 6 than pH > or = 7. CONCLUSION: A potential link (serum androgen levels) between a powerful predictive factor of fertility (W:H ratio) and a potential mechanism of subfertility (low endocervical mucus pH) has been demonstrated. This observation warrants further detailed evaluation particularly as it has been shown that a low endocervical mucus pH may be corrected by simple inexpensive treatment.


Assuntos
Androgênios/sangue , Constituição Corporal , Muco do Colo Uterino/fisiologia , Androstenodiona/sangue , Índice de Massa Corporal , Desidroepiandrosterona/análogos & derivados , Desidroepiandrosterona/sangue , Sulfato de Desidroepiandrosterona , Feminino , Humanos , Concentração de Íons de Hidrogênio , Testosterona/sangue
17.
Fertil Steril ; 68(1): 48-53, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9207583

RESUMO

OBJECTIVE: To determine the changes in follicular fluid (FF) total and free cortisol during the LH surge in naturally ovulating women. PATIENT(S): Twenty-six women having diagnostic laparoscopy during the follicular phase of normal menstrual cycles were selected. INTERVENTION(S): Blood samples were collected 1 day before, the day of, and 1 day after surgery and the results of serum E2 and LH were used to divide the cycles retrospectively into pre- and post-LH surge groups. Follicular fluid was collected during laparoscopy. MAIN OUTCOME MEASURE(S): Serum P, total and free cortisol, and FF volume, E2, P, total cortisol, and free cortisol were measured on the day of surgery. RESULT(S): Median serum and FF P levels were significantly higher in the post-LH surge group compared with the pre-LH surge group (0.54 versus 1.54 ng/mL [1.7 versus 4.85 nmol/L] and 5.03 versus 28.0 micrograms/mL [15.8 versus 88.0 mumol/L], respectively). Follicular fluid volume also increased significantly after the surge (2.5 versus 4.5 mL). Median serum total and free and percent free cortisol were higher after the surge, although not significantly. In contrast, FF total, free, and percent free levels increased dramatically between pre- and post-LH surge samples (4.41 versus 43.6 ng/mL [16.0 versus 158 nmol/L], 0.138 versus 6.68 ng/mL [0.5 versus 24.2 nmol/L], and 3.3% versus 15.0%, respectively; P < 0.05). CONCLUSION(S): An increase in total and free cortisol occurs in the follicle during the LH surge. Cortisol and its regulation by 11 beta-hydroxysteroid dehydrogenase therefore may exert a physiologic role in oocyte maturation or ovulation.


Assuntos
Líquido Folicular/química , Fase Folicular/fisiologia , Hidrocortisona/análise , Hormônio Luteinizante/sangue , Ovulação/fisiologia , Estradiol/análise , Estradiol/sangue , Feminino , Líquido Folicular/fisiologia , Fase Folicular/sangue , Humanos , Hidrocortisona/sangue , Laparoscopia , Ovulação/sangue , Progesterona/análise , Progesterona/sangue
18.
Fertil Steril ; 73(5): 901-7, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10785214

RESUMO

OBJECTIVE: To compare patient and cycle characteristics among three study groups: early ovarian hyperstimulation syndrome (OHSS), late OHSS, and non-OHSS. DESIGN: Prospective observational study. SETTING: University assisted conception service. PATIENT(S): Women undergoing in vitro fertilization, intracytoplasmic sperm injection or gamete intrafallopian transfer treatment at Bristol University In Vitro Fertilization Service between January 1, 1995, and December 31, 1998. INTERVENTION: None. MAIN OUTCOME MEASURE(S): Patient age, prevalence of polycystic ovaries, gonadotropin requirement, peak serum estradiol (E(2)) concentration, number of oocytes retrieved, clinical pregnancy rate, number of gestation sacs, and severity of OHSS. RESULT(S): Women with early OHSS had significantly higher serum E(2) levels and lower gonadotropin requirements than did the other groups. Cycles with either early or late OHSS had significantly more oocytes collected than those without OHSS. Serum E(2) and oocyte numbers did not accurately predict the risk of developing late OHSS. Clinical pregnancies occurred in all cycles with late OHSS, and multiple pregnancies were significantly more frequent in the late OHSS group than in the other groups. Late OHSS was more likely than early OHSS to be severe. CONCLUSION(S): Early OHSS relates to "excessive" preovulatory response to stimulation, whereas late OHSS depends on the occurrence of pregnancy, is likelier to be severe, and is only poorly related to preovulatory events.


Assuntos
Síndrome de Hiperestimulação Ovariana/patologia , Adulto , Fatores Etários , Estradiol/sangue , Feminino , Fertilização in vitro/efeitos adversos , Humanos , Pessoa de Meia-Idade , Observação , Oócitos , Avaliação de Resultados em Cuidados de Saúde , Síndrome de Hiperestimulação Ovariana/sangue , Síndrome de Hiperestimulação Ovariana/complicações , Síndrome do Ovário Policístico/complicações , Gravidez , Estudos Prospectivos , Fatores de Risco , Coleta de Tecidos e Órgãos
19.
Fertil Steril ; 70(2): 214-8, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9696209

RESUMO

OBJECTIVE: To determine whether a relation exists between previous exposure to Chlamydia trachomatis and impaired ovarian response to gonadotropin stimulation. DESIGN: Controlled clinical study. SETTING: Two university IVF centers. PATIENT(S): Two hundred forty-two patients receiving IVF treatment and 81 control patients. Ninety-four patients with a poor response to IVF, defined by cycle cancellation in response to a daily stimulation dose of 300 IU of FSH, and 148 patients with a good response were matched for age. Twenty-eight pregnant controls and 53 controls of proven fertility also were included. INTERVENTION(S): Serum samples were obtained from patients and controls. Serum levels of immunoglobulin (Ig) G antibodies to C. trachomatis were determined by ELISA. MAIN OUTCOME MEASURE(S): The prevalence of serum IgG antibodies to C. trachomatis in critically defined poor responders was compared with that of age-matched good responders. RESULT(S): A significantly higher proportion of poor responders had serum IgG antibodies to C. trachomatis compared with good responders (44.7% and 30.4%, respectively). Patients undergoing IVF had a significantly higher prevalence of IgG antibodies to C. trachomatis (36%) than did either pregnant or nonpregnant controls (12%). CONCLUSION(S): A significantly higher prevalence of serum IgG antibodies to C. trachomatis was observed in critically defined poor responders, suggesting a possible detrimental effect of C. trachomatis on subsequent ovarian function.


Assuntos
Anticorpos Antibacterianos/sangue , Chlamydia trachomatis/imunologia , Fertilização in vitro , Imunoglobulina G/sangue , Menotropinas/uso terapêutico , Ovário/efeitos dos fármacos , Adulto , Feminino , Humanos , Ovário/imunologia , Gravidez , Estimulação Química , Resultado do Tratamento
20.
Fertil Steril ; 73(4): 825-30, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10731548

RESUMO

OBJECTIVE: To further elucidate cortisol metabolism in the follicular microenvironment at the time of oocyte retrieval, the presence of 11beta-hydroxysteroid dehydrogenase (HSD) messenger (m)RNA transcripts in oocytes; cumulus cells; granulosa cells; and CD45(+), CD15(+) leukocytes was assessed semiquantitatively. DESIGN: Controlled study using semiquantitative assessment of 11beta-HSD mRNA. SETTING: University IVF center. PATIENT(S): Twenty-six patients undergoing controlled ovarian hyperstimulation for assisted conception. INTERVENTION(S): Metaphase II oocytes; cumulus cells; granulosa cells, and CD45(+), CD15(+) leukocytes from individual follicular fluid aspirates. MAIN OUTCOME MEASURES: Semiquantitative analysis of PCR products after total RNA extraction and complementary DNA synthesis. RESULT(S): Periovulatory human oocytes; cumulus cells; CD45(+), CD15(+) leukocytes; and granulosa cells consistently express type 1 but not type 2 11beta-HSD mRNA. Expression of mRNA is greatest in cumulus cells. Type 1 11beta-HSD mRNA expression varies considerably in all cell types and among individual follicles and patients. CONCLUSION(S): These studies of mRNA expression suggest that the enzymes present both in and around the periovulatory oocyte will favor a high-cortisol environment.


Assuntos
Hidroxiesteroide Desidrogenases/genética , Leucócitos/enzimologia , Oócitos/fisiologia , Ovário/citologia , 11-beta-Hidroxiesteroide Desidrogenases , Feminino , Fertilização in vitro , Regulação da Expressão Gênica , Gliceraldeído-3-Fosfato Desidrogenases/genética , Células da Granulosa/metabolismo , Humanos , Isoenzimas/genética , Antígenos Comuns de Leucócito/metabolismo , Antígenos CD15/metabolismo , Ovário/enzimologia , Ovulação , Placenta/enzimologia , Valor Preditivo dos Testes , Gravidez , Proteína Tirosina Fosfatase não Receptora Tipo 1 , RNA Mensageiro , Resultado do Tratamento
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