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1.
Gen Comp Endocrinol ; 326: 114070, 2022 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-35671833

RESUMO

Measurement of steroids in wild pinnipeds can facilitate assessment of breeding, nutritional and stress status, and is useful in understanding behavioral responses. Even in young animals, sex steroids may be important in behavioral interactions and immune modulation. Use of saliva can avoid the large fluctuations seen in some steroids in plasma, and can negate the need for venipuncture, making it a potentially useful matrix in the wildlife. However, its utility in estimating steroid levels in wild young pinnipeds has not been evaluated. Here, we investigated the suitability of saliva for steroid hormone analysis in wild grey seal pups during their suckling and post-weaning fast periods. We collected saliva (n = 38) and plasma (n = 71) samples during the breeding season on the Isle of May, Scotland, 2012. We investigated success of sample collection, ease of preparation, accuracy and precision of analysis, and, where possible, comparability of measurements (n = 27) from saliva and plasma. Plasma sampling was rapid, whereas sampling saliva took up to five times longer. Analytical performance criteria (parallelism, accuracy, and precision (intra and inter assay co-efficient of variation (% CV)) of commercial ELISA kits to measure estradiol, testosterone and cortisol in both matrices were assessed. Estradiol and cortisol assays performed well and can be used in plasma and saliva. However, we could not confidently validate testosterone for either matrix. Saliva estradiol correlated with levels in plasma. Saliva sample preparation was faster and simpler than plasma preparation because it did not require extraction. However, given the additional time taken to obtain saliva in the wild, the possibility of blood contamination from oral damage and the lower success rate in obtaining sufficient sample for analysis, we recommend that this matrix only be used as an alternative to plasma sampling measurement in pinnipeds when animals are anaesthetized, tolerate mouth swabbing, or have been trained to accept saliva sampling in captivity.


Assuntos
Saliva , Focas Verdadeiras , Animais , Estradiol/análise , Hidrocortisona/análise , Saliva/química , Esteroides/análise , Testosterona/análise
2.
Science ; 373(6551): 198-204, 2021 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-34244410

RESUMO

Mars' sedimentary rock record preserves information on geological (and potential astrobiological) processes that occurred on the planet billions of years ago. The Curiosity rover is exploring the lower reaches of Mount Sharp, in Gale crater on Mars. A traverse from Vera Rubin ridge to Glen Torridon has allowed Curiosity to examine a lateral transect of rock strata laid down in a martian lake ~3.5 billion years ago. We report spatial differences in the mineralogy of time-equivalent sedimentary rocks <400 meters apart. These differences indicate localized infiltration of silica-poor brines, generated during deposition of overlying magnesium sulfate-bearing strata. We propose that destabilization of silicate minerals driven by silica-poor brines (rarely observed on Earth) was widespread on ancient Mars, because sulfate deposits are globally distributed.

3.
J Geophys Res Planets ; 125(12): e2020JE006527, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33520561

RESUMO

This paper provides an overview of the Curiosity rover's exploration at Vera Rubin ridge (VRR) and summarizes the science results. VRR is a distinct geomorphic feature on lower Aeolis Mons (informally known as Mount Sharp) that was identified in orbital data based on its distinct texture, topographic expression, and association with a hematite spectral signature. Curiosity conducted extensive remote sensing observations, acquired data on dozens of contact science targets, and drilled three outcrop samples from the ridge, as well as one outcrop sample immediately below the ridge. Our observations indicate that strata composing VRR were deposited in a predominantly lacustrine setting and are part of the Murray formation. The rocks within the ridge are chemically in family with underlying Murray formation strata. Red hematite is dispersed throughout much of the VRR bedrock, and this is the source of the orbital spectral detection. Gray hematite is also present in isolated, gray-colored patches concentrated toward the upper elevations of VRR, and these gray patches also contain small, dark Fe-rich nodules. We propose that VRR formed when diagenetic event(s) preferentially hardened rocks, which were subsequently eroded into a ridge by wind. Diagenesis also led to enhanced crystallization and/or cementation that deepened the ferric-related spectral absorptions on the ridge, which helped make them readily distinguishable from orbit. Results add to existing evidence of protracted aqueous environments at Gale crater and give new insight into how diagenesis shaped Mars' rock record.

4.
Anaesthesia ; 72(3): 343-349, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27797158

RESUMO

Significant benefits have been demonstrated with the use of peri-operative checklists. We assessed whether a read-aloud didactic action card would improve performance of cannula cricothyroidotomy in a simulated 'can't intubate, can't oxygenate' scenario. A 17-step action card was devised by an expert panel. Participants in their first 4 years of anaesthetic training were randomly assigned into 'no-card' or 'card' groups. Scenarios were video-recorded for analysis. Fifty-three participants (27 no-card and 26 card) completed the scenario. The number of steps omitted was mean (SD) 6.7 (2.0) in the no-card group vs. 0.3 (0.5); p < 0.001 in the card group, but the no-card group was faster to oxygenation by mean (95% CI) 35.4 (6.6-64.2) s. The Kappa statistic was 0.84 (0.73-0.95). Our study demonstrated that action cards are beneficial in achieving successful front-of-neck access using a cannula cricothyroidotomy technique. Further investigation is required to determine this tool's effectiveness in other front-of-neck access situations, and its role in teaching or clinical management.


Assuntos
Manuseio das Vias Aéreas/métodos , Obstrução das Vias Respiratórias/cirurgia , Lista de Checagem , Traqueotomia/normas , Cânula , Competência Clínica , Cartilagem Cricoide/cirurgia , Emergências , Humanos , Cuidados Intraoperatórios/métodos , Escócia , Cartilagem Tireóidea/cirurgia , Traqueotomia/métodos
5.
Mar Pollut Bull ; 114(1): 372-383, 2017 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-27677390

RESUMO

Shipping noise is a threat to marine wildlife. Grey seals are benthic foragers, and thus experience acoustic noise throughout the water column, which makes them a good model species for a case study of the potential impacts of shipping noise. We used ship track data from the Celtic Sea, seal track data and a coupled ocean-acoustic modelling system to assess the noise exposure of grey seals along their tracks. It was found that the animals experience step changes in sound levels up to ~20dB at a frequency of 125Hz, and ~10dB on average over 10-1000Hz when they dive through the thermocline, particularly during summer. Our results showed large seasonal differences in the noise level experienced by the seals. These results reveal the actual noise exposure by the animals and could help in marine spatial planning.


Assuntos
Monitoramento Ambiental/métodos , Modelos Teóricos , Ruído dos Transportes , Focas Verdadeiras/crescimento & desenvolvimento , Navios , Acústica , Comunicação Animal , Animais , Oceanos e Mares , Focas Verdadeiras/fisiologia , Estações do Ano
6.
Physiol Biochem Zool ; 88(3): 295-310, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25860828

RESUMO

Animals that fast during breeding and/or development, such as phocids, must regulate energy balance carefully to maximize reproductive fitness and survival probability. Adiponectin, produced by adipose tissue, contributes to metabolic regulation by modulating sensitivity to insulin, increasing fatty acid oxidation by liver and muscle, and promoting adipogenesis and lipid storage in fat tissue. We tested the hypotheses that (1) circulating adiponectin, insulin, or relative adiponectin gene expression is related to nutritional state, body mass, and mass gain in wild gray seal pups; (2) plasma adiponectin or insulin is related to maternal lactation duration, body mass, percentage milk fat, or free fatty acid (FFA) concentration; and (3) plasma adiponectin and insulin are correlated with circulating FFA in females and pups. In pups, plasma adiponectin decreased during suckling (linear mixed-effects model [LME]: T = 4.49; P < 0.001) and the early postweaning fast (LME: T = 3.39; P = 0.004). In contrast, their blubber adiponectin gene expression was higher during the early postweaning fast than early in suckling (LME: T = 2.11; P = 0.046). Insulin levels were significantly higher in early (LME: T = 3.52; P = 0.004) and late (LME: T = 6.99; P < 0.001) suckling than in fasting and, given the effect of nutritional state, were also positively related to body mass (LME: T = 3.58; P = 0.004). Adiponectin and insulin levels did not change during lactation and were unrelated to milk FFA or percentage milk fat in adult females. Our data suggest that adiponectin, in conjunction with insulin, may facilitate fat storage in seals and is likely to be particularly important in the development of blubber reserves in pups.


Assuntos
Adiponectina/sangue , Tecido Adiposo/metabolismo , Jejum/metabolismo , Insulina/sangue , Lactação/fisiologia , Leite/química , Focas Verdadeiras/fisiologia , Animais , Animais Lactentes , Peso Corporal , Metabolismo Energético , Feminino , Expressão Gênica
7.
J Comp Physiol B ; 183(8): 1075-88, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23743798

RESUMO

Phocid seals have been proposed as models for diabetes because they exhibit limited insulin response to glucose, high blood glucose and increasing insulin resistance when fasting. Liver glucose-6-phosphatase (G6Pase) catalyses the final step in glucose production and is central to glucose regulation in other animals. G6Pase comprises a translocase (SLC37A4) and a catalytic subunit (G6PC). G6PC and SLC37A4 expression and activity are normally regulated by nutritional state and glucostatic hormones, particularly insulin, and are elevated in diabetes. We tested the hypotheses that (1) grey seal G6PC and SLC37A4 cDNA and predicted protein sequences differ from other species' at functional sites, (2) relative G6Pase protein abundances are lower during feeding than fasting and (3) relative G6Pase protein abundances are related to insulin, insulin receptor phosphorylation and key metabolite levels. We show that G6PC and partial SLC37A4 cDNA sequences encode proteins sharing 82-95 % identity with other mammals. Seal G6PC contained no differences in sites responsible for activity, stability or subcellular location. Several substitutions in seal SLC37A4 were predicted to be tolerated with low probability, which could affect glucose production. Suckling pups had higher relative abundance of both subunits than healthy, postweaned fasting pups. Furthermore, relative G6PC abundance was negatively related to glucose levels. These findings contrast markedly with the response of relative hepatic G6Pase abundance to feeding, fasting, insulin, insulin sensitivity and key metabolites in other animals, and highlight the need to understand the regulation of enzymes involved in glucose control in phocids if these animals are to be informative models of diabetes.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal/fisiologia , Diabetes Mellitus/metabolismo , Glucose-6-Fosfatase/metabolismo , Insulina/metabolismo , Fígado/metabolismo , Focas Verdadeiras/fisiologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Western Blotting , Primers do DNA/genética , DNA Complementar/genética , Modelos Animais de Doenças , Glucose/biossíntese , Glucose-6-Fosfatase/genética , Dados de Sequência Molecular , Proteínas de Transporte de Monossacarídeos/genética , Proteínas de Transporte de Monossacarídeos/metabolismo , Nova Escócia , Escócia , Focas Verdadeiras/genética , Focas Verdadeiras/metabolismo , Alinhamento de Sequência , Análise de Sequência de DNA , Homologia de Sequência , Especificidade da Espécie , Desmame
8.
J Exp Biol ; 216(Pt 6): 984-91, 2013 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-23197086

RESUMO

Seals must manage their energy reserves carefully while they fast on land to ensure that they go to sea with sufficient fuel to sustain them until they find food. Glucocorticoids (GCs) have been implicated in the control of fuel metabolism and termination of fasting in pinnipeds. Here we tested the hypothesis that dexamethasone, an artificial GC, increases fat and protein catabolism, and induces departure from the breeding colony in wild, fasting grey seal pups. A single intramuscular dose of dexamethasone completely suppressed cortisol production for 24-72 h, demonstrating activation of GC receptors. In experiment 1, we compared the effects of a single dose of dexamethasone or saline administered 10 days after weaning on fasting mass and body composition changes, cortisol, blood urea nitrogen (BUN) and glucose levels, and timing of departure from the colony. In experiment 2, we investigated the effects of dexamethasone on short-term (5 days) changes in mass loss, body composition and BUN levels. In experiment 1, dexamethasone induced a short-lived increase in mass loss, but there was no difference in timing of departure between dexamethasone- and saline-treated pups (N=10). In experiment 2, dexamethasone increased protein and water loss and prevented a decrease in BUN levels (N=11). Our data suggest changes in cortisol contribute to regulation of protein catabolism in fasting seal pups, irrespective of the sex of the animal, but do not terminate fasting. By affecting the rate of protein depletion, lasting changes in cortisol levels could influence the amount of time seal pups have to find food, and thus may have important consequences for their survival.


Assuntos
Metabolismo Energético/fisiologia , Jejum/fisiologia , Glucocorticoides/metabolismo , Focas Verdadeiras/fisiologia , Análise de Variância , Animais , Glicemia/metabolismo , Nitrogênio da Ureia Sanguínea , Composição Corporal/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Dexametasona/administração & dosagem , Dexametasona/farmacologia , Metabolismo Energético/efeitos dos fármacos , Feminino , Hidrocortisona/biossíntese , Injeções Intramusculares , Masculino , Focas Verdadeiras/metabolismo
9.
Physiol Biochem Zool ; 83(6): 911-23, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20969447

RESUMO

Development of adequate diving capabilities is crucial for survival of seal pups and may depend on age and body size. We tracked the diving behavior of 20 gray seal pups during their first 3 mo at sea using satellite relay data loggers. We employed quantile analysis to track upper limits of dive duration and percentage time spent diving, and lower limits of surface intervals. When pups first left the breeding colony, extreme (ninety-fifth percentile) dive duration and percentage time spent diving were positively correlated with age, but not mass, at departure. Extreme dive durations and percentage time spent diving peaked at [Formula: see text] d of age at values comparable with those of adults, but were not sustained. Greater peaks in extreme percentage time spent diving occurred in pups that had higher initial values, were older at their peak, and were heavier at departure. Pups that were smaller and less capable divers when they left the colony improved extreme dive durations and percentage time spent diving more rapidly, once they were at sea. Minimum survival time correlated positively with departure mass. Pups that were heavier at weaning thus benefitted from being both larger and older at departure, but smaller pups faced a trade-off. While age at departure had a positive effect on early dive performance, departure mass impacted on peak percentage time spent diving and longer-term survival. We speculate that once small pups have attained a minimum degree of physiological development to support diving, they would benefit by leaving the colony when younger but larger to maximize limited fuel reserves, rather than undergoing further maturation on land away from potential food resources, because poor divers may be able to "catch up" once at sea.


Assuntos
Mergulho/fisiologia , Focas Verdadeiras/fisiologia , Envelhecimento/fisiologia , Animais , Composição Corporal/fisiologia , Tamanho Corporal/fisiologia , Peso Corporal/fisiologia , Comportamento Alimentar/fisiologia , Feminino , Masculino , Focas Verdadeiras/crescimento & desenvolvimento , Fatores de Tempo , Desmame
10.
Am J Transplant ; 9(10): 2270-80, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19681828

RESUMO

Mast cells (MC) have been shown to mediate regulatory T-cell (T(reg))-dependent, peripheral allograft tolerance in both skin and cardiac transplants. Furthermore, T(reg) have been implicated in mitigating IgE-mediated MC degranulation, establishing a dynamic, reciprocal relationship between MC and T(reg) in controlling inflammation. In an allograft tolerance model, it is now shown that intragraft or systemic MC degranulation results in the transient loss of T(reg) suppressor activities with the acute, T-cell dependent rejection of established, tolerant allografts. Upon degranulation, MC mediators can be found in the skin, T(reg) rapidly leave the graft, MC accumulate in the regional lymph node and the T(reg) are impaired in the expression of suppressor molecules. Such a dramatic reversal of T(reg) function and tissue distribution by MC degranulation underscores how allergy may causes the transient breakdown of peripheral tolerance and episodes of acute T-cell inflammation.


Assuntos
Degranulação Celular , Tolerância Imunológica , Mastócitos/patologia , Animais , Sequência de Bases , Primers do DNA , Rejeição de Enxerto , Transplante de Coração/imunologia , Mediadores da Inflamação/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Transplante de Pele/imunologia , Linfócitos T/imunologia , Transplante Homólogo
11.
J Matern Fetal Neonatal Med ; 15(5): 319-23, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15280123

RESUMO

OBJECTIVE: To identify independent predictors of successful labor induction with oral or vaginal misoprostol. METHODS: Women enrolled in four previous randomized trials involving oral or vaginal misoprostol for cervical ripening and labor induction were included in the present cohort study, with dosing of 25-50 microg every 4 to 6 h vaginally (n = 574) or 50 microg every 4 h orally (n = 207). Multiple logistic regression was performed to identify factors independently associated with successful labor induction -- defined as vaginal delivery within 12 h, vaginal delivery within 24 h and spontaneous vaginal delivery. Predictors of Cesarean birth and the need for only one dose of misoprostol were also identified. Variables included in the models were maternal age, weight, height, parity, gravidity, membrane status, route of misoprostol, gestational age, birth weight, and Bishop score and its individual components. RESULTS: Maternal age, height, weight, parity, birth weight, dilatation, effacement and cervical station were associated with vaginal delivery within 24 h of induction. Maternal age, height, weight, nulliparity, birth weight and route of misoprostol were associated with Cesarean birth, with oral misoprostol being associated with a lower rate of Cesarean birth. The need for only one dose of misoprostol was predicted by maternal height, weight, parity, gestational age, Bishop score and route of misoprostol. CONCLUSION: Characteristics of the woman (height, weight, parity), the fetus (birth weight) and some of the individual components of the Bishop score, were associated with successful labor induction, with oral misoprostol being associated with a lower rate of Cesarean birth.


Assuntos
Trabalho de Parto Induzido , Misoprostol/uso terapêutico , Ocitócicos/uso terapêutico , Administração Intravaginal , Administração Oral , Adulto , Estudos de Coortes , Parto Obstétrico , Feminino , Humanos , Misoprostol/administração & dosagem , Ocitócicos/administração & dosagem , Gravidez , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
12.
Nature ; 412(6845): 395-6, 2001 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-11473299
13.
Obstet Gynecol ; 97(6): 926-31, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11384698

RESUMO

OBJECTIVE: To estimate the incidence and timing of excessive uterine activity accompanying induction of labor with misoprostol using different routes (oral or vaginal) and forms (intact tablet or crushed) and to compare these with dinoprostone gel, oxytocin, and spontaneous labor. METHODS: This retrospective cohort study included 519 women at term who had labor induced and 86 women at term in spontaneous labor. Induction agents included misoprostol, dinoprostone, or oxytocin. Fetal heart rate and uterine activity tracings were analyzed independently by three maternal-fetal medicine physicians. The diagnosis of tachysystole or hyperstimulation required the agreement of two or more reviewers. RESULTS: The incidence of tachysystole was highest with misoprostol administered by vaginal tablet (misoprostol vaginal tablet 50 microg every 4 hours, 48.6%; vaginal tablet crushed 50 microg and suspended in hydroxyethyl gel every 4 hours, 30.7%, P =.009; oral tablet 50 microg every 4 hours, 22.2%, P =.001; oral tablet crushed 50 microg every 4 hours, 15.5%, P <.001; dinoprostone gel, 33.0%, P =.022; intravenous oxytocin, 30.2%, P =.027; and spontaneous onset of labor, 23.3%, P <.001). Hyperstimulation occurred more often with dinoprostone gel (16.5%) than with other forms of induction or spontaneous labor. Hyperstimulation occurred significantly more often with vaginal misoprostol crushed tablet (7.9%) and vaginal misoprostol intact tablet (7.6%) than with crushed oral misoprostol (1.0%) (P =.016 and.018, respectively). There was a shorter time to tachysystole with increasing doses of vaginal misoprostol tablet (P =.01). CONCLUSION: The incidence of tachysystole and hyperstimulation, and time to tachysystole, varied depending on the route and form of misoprostol given.


Assuntos
Trabalho de Parto Induzido/efeitos adversos , Misoprostol/efeitos adversos , Ocitócicos/efeitos adversos , Contração Uterina/efeitos dos fármacos , Administração Intravaginal , Administração Oral , Adulto , Estudos de Coortes , Dinoprostona/administração & dosagem , Dinoprostona/efeitos adversos , Relação Dose-Resposta a Droga , Feminino , Seguimentos , Humanos , Trabalho de Parto Induzido/métodos , Misoprostol/administração & dosagem , Ocitócicos/administração & dosagem , Ocitocina/administração & dosagem , Ocitocina/efeitos adversos , Gravidez , Probabilidade , Estudos Retrospectivos , Medição de Risco , Monitorização Uterina/métodos
14.
Obstet Gynecol ; 97(5 Pt 2): 815-6, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11336763

RESUMO

BACKGROUND: Cytochrome oxidase-deficient mitochondrial myopathies represent a heterogeneous group of muscle disorders. Physical stress can cause life-threatening risks related to rhabdomyolysis or respiratory compromise. CASE: A 21-year-old primigravida with cytochrome C oxidase-deficient mitochondrial myopathy who presented for obstetric care at 8 weeks' gestation complained of muscle fatigue and spasm after exertion. The increased metabolic demands of pregnancy led to worsening pain, muscle fatigue, and ultimately complete immobility. CONCLUSION: Cytochrome oxidase-deficient mitochondrial myopathies are rare but serious complications of pregnancy.


Assuntos
Deficiência de Citocromo-c Oxidase , Miopatias Mitocondriais/terapia , Complicações na Gravidez/terapia , Adulto , Feminino , Humanos , Recém-Nascido , Gravidez , Resultado da Gravidez , Cuidado Pré-Natal
15.
J Exp Biol ; 204(Pt 4): 649-62, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11171347

RESUMO

This study seeks to understand how the physiological constraints of diving may change on a daily and seasonal basis. Dive data were obtained from southern elephant seals (Mirounga leonina) from South Georgia using satellite relay data loggers. We analysed the longest (95th percentile) dive durations as proxies for physiological dive limits. A strong, significant relationship existed between the duration of these dives and the time of day and week of year in which they were performed. The depth of the deepest dives also showed a significant, but far less consistent, relationship with local time of day and season. Changes in the duration of the longest dives occurred irrespective of their depth. Dives were longest in the morning (04:00-12:00 h) and shortest in the evening (16:00-00:00 h). The size of the fluctuation varied among animals from 4.0 to 20.0 min. The daily pattern in dive depth was phase-shifted in relation to the diurnal rhythm in dive duration. Dives were deeper at midday and shallower around midnight. Greater daily changes in duration occurred in seals feeding in the open ocean than in those foraging on the continental shelf. The seasonal peak in the duration of the longest dives coincided with austral midwinter. The size of the increase in dive duration from autumn/spring to winter ranged from 11.5 to 30.0 min. Changes in depth of the longest dives were not consistently associated with particular times of year. The substantial diurnal and seasonal fluctuations in maximum dive duration may be a result of changes in the physiological capacity to remain submerged, in addition to temporal changes in the ecological constraints on dive behaviour. We speculate about the role of melatonin as a hormonal mediator of diving capability.


Assuntos
Comportamento Animal/fisiologia , Ritmo Circadiano/fisiologia , Mergulho/fisiologia , Focas Verdadeiras/fisiologia , Estações do Ano , Animais , Coleta de Dados/métodos , Feminino , Masculino , Movimento , Análise de Regressão , Comunicações Via Satélite , Fatores de Tempo
16.
BJOG ; 107(8): 964-8, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10955426

RESUMO

OBJECTIVES: To evaluate women's sexual experience in pregnancy, and to describe their sources of information regarding sexuality during this period. DESIGN: Cross-sectional study. SETTING: The offices of obstetricians providing obstetric care in a tertiary care university hospital in St. John's, Newfoundland, Canada. POPULATION: One hundred and forty-one pregnant women. METHODS: Pregnant women anonymously completed self-administered questionnaires regarding sexuality and sexual activity during pregnancy. Responses were summarised using descriptive statistics, and comparisons were made between the trimesters of pregnancy. Multiple logistic regression was performed to assess the influences of a variety of factors on sexual activity. RESULTS: Vaginal intercourse and sexual activity overall decreased throughout pregnancy (P = 0.004 and 0.05, respectively) with the trimester of pregnancy being the only independent predictor. Most women reported a decrease in sexual desire (58%). Overall, 49% of women worried that sexual intercourse may harm the pregnancy. Concerns regarding sexual activity leading to preterm labour or premature rupture of membranes increased as the pregnancy progressed (P < 0-001 and P = 0-001, respectively). Only 29% of women discussed sexual activity in pregnancy with their doctor and 49% of these women raised the issue first, with 34% feeling uncomfortable in bringing up the topic themselves. Most women (76%) who had not discussed these issues with their doctor felt they should be discussed. CONCLUSIONS: A reduction in sexual activity, vaginal intercourse and sexual desire occurs in many women as pregnancy progresses. Both the woman and her partner have concerns regarding complications in the pregnancy as a result of sexual intercourse. The majority of women wish to discuss these issues with their doctor, but are not always comfortable raising the topic themselves.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Gravidez/psicologia , Comportamento Sexual/psicologia , Adulto , Canadá/epidemiologia , Estudos Transversais , Feminino , Humanos , Modelos Logísticos , Trimestres da Gravidez , Sexualidade/psicologia
18.
Obstet Gynecol ; 94(6): 994-9, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10576189

RESUMO

OBJECTIVES: To compare labor induction intervals between oral misoprostol and intravenous oxytocin in women who present at term with premature rupture of membranes. METHODS: One hundred eight women were randomly assigned to misoprostol 50 microg orally every 4 hours as needed or intravenous oxytocin. The primary outcome measure was time from induction to vaginal delivery. Sample size was calculated using a two-tailed alpha of 0.05 and power of 80%. RESULTS: Baseline demographic data, including maternal age, gestation, parity, Bishop score, birth weight, and group B streptococcal status, were similar. The mean time +/-standard deviation to vaginal birth with oral misoprostol was 720+/-382 minutes compared with 501+/-389 minutes with oxytocin (P = .007). The durations of the first, second, and third stages of labor were similar. There were no differences in maternal secondary outcomes, including cesarean birth (eight and seven, respectively), infection, maternal satisfaction with labor, epidural use, perineal trauma, manual placental removal, or gastrointestinal side effects. Neonatal outcomes including cord pH, Apgar scores, infection, and admission to neonatal intensive care unit were not different. CONCLUSION: Although labor induction with oral misoprostol was effective, oxytocin resulted in a shorter induction-to-delivery interval. Active labor intervals and other maternal and neonatal outcomes were similar.


Assuntos
Ruptura Prematura de Membranas Fetais/terapia , Trabalho de Parto Induzido , Misoprostol , Ocitócicos , Ocitocina , Feminino , Humanos , Gravidez , Resultado do Tratamento
19.
Obstet Gynecol ; 92(4 Pt 1): 481-6, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9764615

RESUMO

OBJECTIVE: To test the null hypothesis that administering misoprostol orally or vaginally will result in no difference in time to vaginal birth, and to determine whether different frequencies of tachysystole and hyperstimulation are associated with route of administration. METHODS: Two hundred six women after 37 completed weeks' gestation who presented with an indication for induction were randomly assigned to receive misoprostol (50 microg) either orally or vaginally every 4 hours as needed to induce labor. Placebo use and allocation concealment accomplished blinding until data analysis was completed. Sample size was calculated to allow a two-tailed alpha of .05 and power (1-beta) of 80%. All fetal heart rate and uterine activity graphs were classified according to Curtis' criteria before induction groups were unmasked. RESULTS: Analysis involved 104 women in the oral group and 102 in the vaginal group. The mean time (+/-standard deviation) to vaginal birth with oral misoprostol was 1072 (+/-593) minutes compared with 846 (+/-385) minutes with the vaginal protocol (P=.004). There were no significant differences in cesarean rate, epidural use, or neonatal outcomes. More frequent tachysystole for 20 minutes (P < .01) and hyperstimulation (P < .04) were observed with vaginal misoprostol. No neonatal asphyxia occurred in either group. CONCLUSION: Misoprostol effectively induces labor, given orally or vaginally. There is a shorter interval to vaginal birth with vaginal application; however, the more frequent occurrence of fetal heart rate graph abnormalities in this group suggests that, until the optimal dosing interval for vaginal use is determined, the preferred route of misoprostol administration might be oral.


Assuntos
Abortivos não Esteroides/administração & dosagem , Trabalho de Parto Induzido , Misoprostol/administração & dosagem , Administração Intravaginal , Administração Oral , Adulto , Feminino , Humanos , Gravidez
20.
Nucleic Acids Res ; 25(8): 1649-57, 1997 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-9092675

RESUMO

RNA challenge phages are derivatives of bacteriophage P22 that enable direct genetic selection for a specific RNA-protein interaction. The bacteriophage P22 R17 encodes a wild-type R17 operator site and undergoes lysogenic development following infection of susceptible bacterial strains that express the R17/MS2 coat protein. A P22 R17 derivative with an OcRNA site (P22 R17 [A(-10)U]) develops lytically following infection of these strains. RNA challenge phages can be used to isolate second-site coat protein suppressors that recognize an OcRNA sequence by selecting for lysogens with a P22 R17 [Oc] phage derivative. The bacteriophage derivative P22 R17 [A(-10)U] was used in one such scheme to isolate two classes of genes that encode R17 coat proteins with altered capsid assembly properties and expanded RNA-binding characteristics. These mutations map outside the RNA-binding surface and include amino acid substitutions that interfere with interactions between coat protein dimers in the formation of the stable phage capsid. One class of mutants encodes substitutions at the highly conserved first and second positions of the mature coat protein. N-terminal sequence analysis of these mutants reveals that coat proteins with substitutions only at position 1 are defective in post-translational processing of the initiator methionine. All selected proteins possess expanded RNA-binding properties since they direct efficient lysogen formation for P22 R17 and P22 R17 [A(-10)U]; however, bacterial strains that express the protein mutants remain sensitive to lytic infection by other P22 R17 [Oc] bacteriophages. The described selection strategy provides a novel genetic approach to dissecting protein structure within RNA-binding proteins.


Assuntos
Bacteriófago P22/genética , Proteínas do Capsídeo , Capsídeo/genética , Proteínas de Ligação a RNA/genética , Seleção Genética , Sequência de Aminoácidos , Sequência de Bases , Capsídeo/biossíntese , Códon , Primers do DNA , DNA Viral/química , DNA Viral/metabolismo , Genes Virais , Cinética , Lisogenia , Mutagênese Sítio-Dirigida , Conformação de Ácido Nucleico , Reação em Cadeia da Polimerase , Proteínas de Ligação a RNA/biossíntese , Proteínas Recombinantes/biossíntese , Recombinação Genética , Salmonella typhimurium/virologia , Transcrição Gênica , Proteínas Estruturais Virais/genética
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