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1.
Int J Obstet Anesth ; 48: 103212, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34500190

RESUMO

COVID-19 in pregnancy increases the risk of caesarean section. We present two cases of late gestation pregnant women with severe COVID-19. Both were successfully treated with mechanical ventilation without termination of pregnancy and, following recovery from COVID-19, had vaginal deliveries at term. These two cases demonstrate the possibility of treating pregnant women with severe COVID-19 with mechanical ventilation in the late second and early third trimesters without them having a pre-term delivery. With a multidisciplinary approach, such management could avoid the maternal risks of surgery during a severe infection and, at the same time, enable term birth with a lower risk of neonatal complications.


Assuntos
COVID-19/terapia , Nascido Vivo , Respiração com Pressão Positiva/métodos , Complicações Infecciosas na Gravidez/terapia , Adulto , Analgésicos/uso terapêutico , Antibacterianos/uso terapêutico , Anticoagulantes/uso terapêutico , COVID-19/fisiopatologia , Feminino , Humanos , Hipnóticos e Sedativos/uso terapêutico , Fármacos Neuromusculares não Despolarizantes/uso terapêutico , Gravidez , Complicações Infecciosas na Gravidez/fisiopatologia , Resultado da Gravidez , SARS-CoV-2 , Resultado do Tratamento , Adulto Jovem
2.
Diabet Med ; 37(12): 2050-2057, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32027045

RESUMO

AIM: To assess whether incidence of maternal and neonatal outcomes for women with or without gestational diabetes mellitus (GDM) have changed over time. METHODS: Population-based cohort study in Sweden including all singleton pregnancies over the period 1998-2012. GDM was diagnosed following Diabetic Pregnancy Study Group 1991 criteria. Poisson regression or negative binomial regression was used to model yearly relative change in numbers of cases and incidence of the outcomes with 95% confidence intervals (CI), and yearly absolute change in birthweight z-score. RESULTS: The study included 1 455 667 pregnancies. The number of pregnancies increased over time and the overall prevalence of GDM was 1%. For women with GDM there was a significantly decreasing trend in incidence per year for large for gestational age (LGA) (0.986, 95% CI 0.975 to 0.996), birthweight z-score (-0.012, 95% CI -0.017 to -0.007) and birth trauma (0.937, 95% CI 0.907 to 0.968). The trend for small for gestational age (SGA) among women with GDM increased by an odds ratio per year (1.016, 95% CI 1.002 to 1.029). No significant interaction tests for maternal characteristics were found. Trends in outcomes for women without diabetes were similar to those for women with GDM. CONCLUSIONS: This study shows that there were improvements in pregnancy outcomes for women with GDM between 1998 and 2012, although the incidence of SGA increased. Improvements followed similar trends in the background population. Inequalities in obstetric outcomes between women with GDM and those without have continued unchanged over 15 years, suggesting that new management strategies are required to reduce this gap.


Assuntos
Traumatismos do Nascimento/epidemiologia , Diabetes Gestacional/epidemiologia , Macrossomia Fetal/epidemiologia , Resultado da Gravidez/epidemiologia , Adulto , Estudos de Coortes , Feminino , Retardo do Crescimento Fetal/epidemiologia , Humanos , Recém-Nascido , Recém-Nascido Pequeno para a Idade Gestacional , Razão de Chances , Mortalidade Perinatal/tendências , Gravidez , Nascimento Prematuro/epidemiologia , Prevalência , Suécia/epidemiologia , Adulto Jovem
3.
Diabet Med ; 36(2): 151-157, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30698864

RESUMO

AIMS: To evaluate the interaction effects of gestational diabetes (GDM) with obesity on perinatal outcomes. METHODS: A population-based cohort study in Sweden excluding women without pre-gestational diabetes with a singleton birth between 1998 and 2012. Logistic regression was performed to evaluate the potential independent associations of GDM and BMI with adverse perinatal outcomes as well as their interactions. Main outcome measures were malformations, stillbirths, perinatal mortality, low Apgar score, fetal distress, prematurity and Erb's palsy. RESULTS: Some 1,294,006 women were included, with a GDM prevalence of 1% (n = 14,833). The rate of overweight/obesity was 67.7% in the GDM-group and 36.1% in the non-GDM-group. No significant interaction existed. Offspring of women with GDM had significantly increased risk of malformations, adjusted odds ratio (aOR) 1.16 (95% confidence intervals 1.06-1.26), prematurity, aOR 1.86 (1.76-1. 98), low Apgar score, aOR 1.36 (1.10-1.70), fetal distress, aOR 1.09 (1.02-1.16) and Erb's palsy aOR 2.26 (1.79-2.86). No risk for stillbirth or perinatal mortality was seen. Offspring of overweight (BMI 25-29.9 kg/m2 ), obese (BMI 30-34.9 kg/m2 ) and severely obese women (BMI ≥ 35.0 kg/m2 ) had significantly increased risks of all outcomes including stillbirth 1.51 (1.40-1.62) to 2.85 (2.52-3.22) and perinatal mortality 1.49 (1.40-1.59) to 2.83 (2.54-3.15). CONCLUSIONS: There is no interaction effect between GDM and BMI for the studied outcomes. Higher BMI and GDM are major independent risk factors for most serious adverse perinatal outcomes. More effective pre-pregnancy and antenatal interventions are required to prevent serious adverse pregnancy outcomes among women with either GDM or high BMI.


Assuntos
Adiposidade/fisiologia , Diabetes Gestacional/epidemiologia , Adulto , Índice de Massa Corporal , Anormalidades Congênitas/epidemiologia , Feminino , Morte Fetal/etiologia , Humanos , Idade Materna , Obesidade/epidemiologia , Sobrepeso/epidemiologia , Gravidez , Resultado da Gravidez/epidemiologia , Estudos Prospectivos , Sistema de Registros , Fatores de Risco , Natimorto/epidemiologia , Suécia/epidemiologia
4.
Stud Mycol ; 91: 79-99, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30487660

RESUMO

We classified the genes encoding carbohydrate-active enzymes (CAZymes) in 17 sequenced genomes representing 16 evolutionarily diverse Aspergillus species. We performed a phylogenetic analysis of the encoding enzymes, along with experimentally characterized CAZymes, to assign molecular function to the Aspergilli CAZyme families and subfamilies. Genome content analysis revealed that the numbers of CAZy genes per CAZy family related to plant biomass degradation follow closely the taxonomic distance between the species. On the other hand, growth analysis showed almost no correlation between the number of CAZyme genes and the efficiency in polysaccharide utilization. The exception is A. clavatus where a reduced number of pectinolytic enzymes can be correlated with poor growth on pectin. To gain detailed information on the enzymes used by Aspergilli to breakdown complex biomass, we conducted exoproteome analysis by mass spectrometry. These results showed that Aspergilli produce many different enzymes mixtures in the presence of sugar beet pulp and wheat bran. Despite the diverse enzyme mixtures produced, species of section Nigri, A. aculeatus, A. nidulans and A. terreus, produce mixtures of enzymes with activities that are capable of digesting all the major polysaccharides in the available substrates, suggesting that they are capable of degrading all the polysaccharides present simultaneously. For the other Aspergilli, typically the enzymes produced are targeted to a subset of polysaccharides present, suggesting that they can digest only a subset of polysaccharides at a given time.

5.
Diabet Med ; 33(8): 1045-51, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27172974

RESUMO

AIM: To analyse the impact of overweight and obesity on the risk of adverse maternal outcomes and fetal macrosomia in pregnancies of women treated for severe gestational diabetes. METHODS: This was a population-based cohort study including all singleton pregnancies in Sweden without pre-existing diabetes in the period 1998-2012. Only mothers with an early- pregnancy BMI of ≥ 18.5 kg/m² were included. Logistic regression analysis was used to determine odds ratios with 95% CIs for maternal outcomes and fetal growth. Analyses were stratified by maternal gestational diabetes/non-gestational diabetes to investigate the impact of overweight/obesity in each group. RESULTS: Of 1 249 908 singleton births, 13 057 were diagnosed with gestational diabetes (1.0%). Overweight/obesity had the same impact on the risks of caesarean section and fetal macrosomia in pregnancies with and without gestational diabetes, but the impact of maternal BMI on the risk of preeclampsia was less pronounced in women with gestational diabetes. Normal-weight women with gestational diabetes had an increased risk of caesarean section [odds ratio 1.26 (95% CI 1.16-1.37)], preeclampsia [odds ratio 2.03 (95% CI 1.71-2.41)] and large-for-gestational-age infants [odds ratio 2.25 (95% CI 2.06-2.46)]. Risks were similar in the overweight group without gestational diabetes, caesarean section [odds ratio 1.34 (1.33-1.36)], preeclampsia odds ratio [1.76 (95% CI 1.72-1.81)], large-for-gestational-age [odds ratio 1.76 (95% CI 1.74-1.79)]. CONCLUSIONS: Maternal overweight and obesity is associated with similar increments in risks of adverse maternal outcomes and delivery of large-for-gestational-age infants in women with and without gestational diabetes. Obese women with gestational diabetes are defined as a high-risk group. Normal-weight women with gestational diabetes have similar risks of adverse outcomes to overweight women without gestational diabetes.


Assuntos
Cesárea/estatística & dados numéricos , Diabetes Gestacional/epidemiologia , Macrossomia Fetal/epidemiologia , Obesidade/epidemiologia , Pré-Eclâmpsia/epidemiologia , Adulto , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Idade Gestacional , Humanos , Modelos Logísticos , Razão de Chances , Sobrepeso/epidemiologia , Gravidez , Complicações na Gravidez/epidemiologia , Índice de Gravidade de Doença , Suécia/epidemiologia , Adulto Jovem
7.
Aliment Pharmacol Ther ; 28(9): 1140-6, 2008 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-18624788

RESUMO

BACKGROUND: Eosinophilic oesophagitis (EoO) may be a common finding in adults presenting with dysphagia. AIM: To identify the risk factors and prevalence of EoO in an adult population with dysphagia. METHODS: All patients with dysphagia referred for an upper endoscopy (EGD) were asked to participate. Patients completed a detailed questionnaire followed by EGD with four quadrant biopsies in the distal and mid-oesophagus. Primary endpoint was the prevalence of EoO; secondary endpoints included age, gender, asthma, food allergies, gastro-oesophageal reflux disease/dysphagia score and endoscopic findings. RESULTS: Two hundred and sixty-one patients enrolled between December 2005 and January 2007. Thirty-one patients (12%) met pathological criteria for EoO. There was no difference in EoO prevalence within each gender. Mean age of EoO patients was 42 +/- 15 vs. 61 +/- 15 for non-EoO patients (P < 0.001). EoO was diagnosed in 35% of patients <50 years of age. EoO was present in 22% of asthmatics vs. 9% non-asthmatics (P < 0.01). EoO was present in 36.8% of patients with self-reported food allergies vs. 9.3% those without allergy (P < 0.001). A 13/31(42%) of EoO patients did not have the classic EGD findings (rings +/- furrows) and would have been missed without oesophageal biopsies. CONCLUSIONS: Eosinophilic oesophagitis was diagnosed in 12% of the patients presenting with dysphagia with relative risk of 9.5 if age <50 years. Oesophageal biopsies are warranted in patients presenting with dysphagia especially in the younger population. Patients may not present with classic endoscopic findings and EoO can be missed without biopsies.


Assuntos
Transtornos de Deglutição/etiologia , Eosinofilia/complicações , Esofagite/complicações , Esôfago/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Transtornos de Deglutição/patologia , Eosinofilia/patologia , Esofagite/patologia , Esofagoscopia/métodos , Esôfago/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Estatística como Assunto , Adulto Jovem
8.
Med Biol Eng Comput ; 43(2): 212-7, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15865130

RESUMO

Heart sounds can be considered as mechanical fingerprints of myocardial function. The third heart sound normally occurs in children but disappears with maturation. The sound can also appear in patients with heart failure. The sound is characterised by its low-amplitude and low-frequency content, which makes it difficult to identify by the traditional use of the stethoscope. A wavelet-based method has recently been developed for detection of the third heart sound. This study investigated if the third heart sound could be identified in patients with heart failure using this detection method. The method was also compared with auscultation using conventional phonocardiography and with characterisation of the patients with echocardiography. In the first study, 87% of the third heart sounds were detected using the wavelet method, 12% were missed, and 6% were false positive. In study 2, the wavelet-detection method identified 87% of the patients using the third heart sound, and regular phonocardiography identified two (25%) of the subjects.


Assuntos
Auscultação Cardíaca/métodos , Insuficiência Cardíaca/diagnóstico , Ruídos Cardíacos , Processamento de Sinais Assistido por Computador , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fonocardiografia
9.
Mol Cell Endocrinol ; 153(1-2): 137-45, 1999 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-10459861

RESUMO

Activins were originally isolated based on their ability to stimulate follicle-stimulating hormone secretion but later they have been shown to regulate a number of different cellular functions such as nerve cell survival, mesoderm induction during early embryogenesis as well as hematopoiesis. We studied the regulation of activin A, a homodimer of betaA-subunits, mRNA and protein in K562 erythroleukemia cells, which are known to be induced toward the erythroid lineage in response to activin or TGF-beta or toward the megakaryocytic lineage by the phorbol ester protein kinase C activator 12-O-tetradecanoylphorbol-13-acetate (TPA). Here we show by Northern blot analysis as well as by Western and ligand blotting that TPA strongly promotes activin betaA-subunit mRNA and activin A protein expression in K562 cells in time- and concentration dependent manner. In contrast, neither activin A nor TGF-beta induced betaA-subunit mRNA expression during erythroid differentiation in K562 cells. Interestingly, whereas activin type II receptors are not regulated during K562 cell differentiation (Hilden et al. (1994) Blood 83, 2163-2170), we now show that the activin type I and IB receptor mRNAs are clearly induced by TPA but not by activin or TGF-beta. We also show that the inducing effect of TPA on expression of activin betaA-subunit mRNA is potentiated by the protein kinase A activator 8-bromo-cAMP. We conclude that activin A and its type I receptors appear to be co-ordinately up-regulated during megakaryocytic differentiation of K562 cells.


Assuntos
Diferenciação Celular , Expressão Gênica , Inibinas/genética , Células K562/metabolismo , Receptores de Fatores de Crescimento/genética , Acetato de Tetradecanoilforbol/farmacologia , 8-Bromo Monofosfato de Adenosina Cíclica/farmacologia , Receptores de Ativinas , Ativinas , Southern Blotting , Proteína Quinase Tipo II Dependente de AMP Cíclico , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Dimerização , Sinergismo Farmacológico , Ativação Enzimática/efeitos dos fármacos , Humanos , Células K562/citologia , Megacariócitos/citologia , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Crescimento Transformador beta/farmacologia
11.
Endocrinology ; 136(10): 4382-9, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7664658

RESUMO

Recent studies have indicated that activin and inhibin may act as local regulators of cell growth and steroidogenesis in the human ovary. We studied the effect of recombinant human activin A and purified bovine inhibin A on the steady state messenger RNA (mRNA) levels of the inhibin/activin alpha-, beta A-, and beta B-subunits in cultured granulosa-luteal (GL) cells from preovulatory ovarian follicles of women undergoing in vitro fertilization. Activin A induced the expression of a 4.8-kilobase beta B-subunit mRNA transcript without affecting basal expression levels of the alpha- and beta A-subunit mRNAs. It stimulated beta B-subunit mRNA levels in a concentration- and time-dependent manner. Maximal stimulation of beta B-subunit mRNA levels was obtained with 30-100 ng/ml activin A. The level of beta B-subunit mRNAs increased significantly 8 h after stimulation, rising gradually thereafter to a maximum at 48 h. Inhibin A did not affect the mRNA levels of any inhibin/activin subunits, nor did it inhibit the effect of activin A. Recombinant human follistatin did not affect basal beta B-subunit mRNA levels, but it neutralized the effect of activin A. Although hCG induces inhibin/activin alpha- and beta A-subunit mRNA levels in human GL cells, it did not increase basal beta B-subunit levels. By contrast, it inhibited activin A-induced beta B-subunit mRNA levels. On the other hand, activin A decreased hCG-induced mRNA levels of the inhibin alpha-subunit and cytochrome P450 side-chain cleavage (P450scc) enzyme, an important rate-limiting enzyme in human GL cell progestin synthesis. Moreover, we observed by Northern blot analysis that cultured human GL cells as well as freshly isolated preovulatory granulosa cells express the specific mRNAs for all currently known serine/threonine kinase activin receptors, i.e. activin receptors I, IB, II, and IIB. Our results suggest that in GL cells, activin A may locally stimulate synthesis of the beta B-subunit in an autocrine or paracrine manner, and that in human ovary, regulation of the beta B-subunit differs from that of the alpha- and beta A-subunits.


Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Células da Granulosa/metabolismo , Inibinas/genética , Inibinas/farmacologia , RNA Mensageiro/análise , Receptores de Fatores de Crescimento/genética , Receptores de Ativinas , Ativinas , Sequência de Bases , Células Cultivadas , Gonadotropina Coriônica/farmacologia , Relação Dose-Resposta a Droga , Feminino , Folistatina , Glicoproteínas/farmacologia , Humanos , Dados de Sequência Molecular , Proteínas Recombinantes/farmacologia
12.
Mech Dev ; 50(2-3): 229-45, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7619733

RESUMO

We report that activin profoundly alters epithelial branching morphogenesis of embryonic mouse salivary gland, pancreas and kidney rudiments in culture, indicating that it may play a role as a morphogen during mammalian organogenesis. In developing pancreas and salivary gland rudiments, activin causes severe disruption of normal lobulation patterns of the epithelium whereas follistatin, an activin-binding protein, counteracts the effect of activin. In the kidney, activin delays branching of the ureter bud and reduces the number of secondary branches. TGF-beta induces a pattern of aberrant branching in the ureter bud derived epithelium distinct from that seen for activin. Reverse-transcriptase polymerase chain reaction, Northern hybridization and in situ hybridization analyses indicate that these developing tissues express the mRNA transcripts for activin subunits, follistatin or activin receptors. Our results are suggestive of a potential role for the activin-follistatin system as an intrinsic regulator of epithelial branching morphogenesis during mammalian organogenesis.


Assuntos
Substâncias de Crescimento/toxicidade , Inibinas/toxicidade , Rim/efeitos dos fármacos , Pâncreas/efeitos dos fármacos , Glândulas Salivares/efeitos dos fármacos , Receptores de Ativinas , Ativinas , Sequência de Aminoácidos , Animais , Sequência de Bases , Desenvolvimento Embrionário e Fetal/efeitos dos fármacos , Folistatina , Glicoproteínas/genética , Humanos , Inibinas/genética , Rim/embriologia , Camundongos , Camundongos Endogâmicos CBA , Dados de Sequência Molecular , Morfogênese/efeitos dos fármacos , Técnicas de Cultura de Órgãos , Pâncreas/embriologia , RNA Mensageiro/biossíntese , Receptores de Fatores de Crescimento/genética , Glândulas Salivares/embriologia
13.
J Clin Endocrinol Metab ; 79(6): 1670-7, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7989473

RESUMO

We studied the effects of recombinant human FSH (rhFSH) and purified hCG on the steady state messenger ribonucleic acid (mRNA) levels of inhibin alpha- and beta A-subunits in cultured granulosa-luteal cells of preovulatory ovarian follicles obtained from women undergoing in vitro fertilization. Specific mRNA transcripts for the alpha- and beta A-subunits were detected in Northern and dot blot filter hybridization analyses, and the levels of these mRNAs were induced by rhFSH and hCG in a distinct concentration- and time-dependent manner. The basal and hCG-stimulated alpha-subunit mRNA levels were first determined at 2- to 3-day intervals over a 3- to 10-day culture period after the initiation of the cultures. Both the basal and hCG-stimulated alpha-subunit mRNA levels declined steadily during culture, but the maximal relative stimulatory effect of hCG was observed on day 7 of culture. All subsequent experiments, therefore, were performed on days 6-8 of culture. Both gonadotropins induced alpha-subunit mRNA levels with slower kinetics than those of the beta A-subunit. Varying between experiments, rhFSH and hCG increased the expression of the alpha-subunit with a maximal effect of 2.5- to 5.7-fold and 1.7- to 7.2-fold, respectively, above basal levels 24-48 h after stimulation. rhFSH and hCG induced beta A-subunit mRNA levels with 3.0- to 5.8-fold and 2.3- to 8.6-fold increases above basal levels, respectively, at 2 h; thereafter, only moderate or no stimulation of the beta A-subunit mRNA levels could be detected at 7-48 h. Treatment of the cells with the RNA synthesis inhibitor actinomycin-D prevented the induction of alpha-subunit mRNA levels by hCG, and no significant differences were detected in the stability of alpha-subunit mRNA transcripts in hCG-treated cells vs. untreated cultures. This indicates that hCG induces transcription of the alpha-subunit gene rather than maintains the levels of preexisting transcripts. As the kinetics of induction of alpha- and beta A-subunit mRNAs by gonadotropins were different, we examined how the inhibition of protein synthesis affects the induction of alpha- and beta A-subunit mRNAs by hCG. Cycloheximide had no effect on basal alpha-subunit mRNA levels at 2 or 24 h. However, it inhibited at 24 h the induction of the alpha-subunit by hCG.(ABSTRACT TRUNCATED AT 400 WORDS)


Assuntos
Gonadotropina Coriônica/farmacologia , Hormônio Foliculoestimulante/farmacologia , Células da Granulosa/metabolismo , Inibinas/genética , Células Lúteas/metabolismo , RNA Mensageiro/biossíntese , Northern Blotting , Células Cultivadas , Cicloeximida/farmacologia , Dactinomicina/farmacologia , Feminino , Células da Granulosa/efeitos dos fármacos , Humanos , Cinética , Células Lúteas/efeitos dos fármacos , Proteínas Recombinantes/farmacologia , Fatores de Tempo
14.
Endocrinology ; 135(5): 2196-203, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7956942

RESUMO

We studied the effect of hCG on follistatin (FS) messenger RNA (mRNA) steady state levels and protein secretion in cultures of human granulosa-luteal (GL) cells obtained at oocyte harvest for in vitro fertilization. Three different overlapping FS complementary DNA (cDNA) fragments were generated by reverse transcription-polymerase chain reaction from human GL cell RNA. Together, these fragments covered the open reading frame, which appeared to be identical in sequence to previously isolated human testis-derived cDNAs. An alternative splicing event at the 3'-end of the FS transcript previously shown to give rise to transcripts encoding 344 amino acid (aa) and 317-aa proteins was also observed. In Northern analysis of human GL cell RNA, a major 2.5-kilobase transcript and a minor 1.5-kilobase FS transcript were detected, and the steady state levels of both mRNAs were induced by an 8-h stimulation with hCG (30 ng/ml). Time and concentration dependence studies on the effect of hCG were performed with cells cultured for 6-8 days before hormone treatment. Time-course experiments indicated that hCG (30 ng/ml) markedly induces FS mRNA levels as early as 2 h after stimulation. The maximal response to hCG stimulation, about 9-fold (mean of five experiments) above basal levels, was observed at 6-8 h, and thereafter, only moderate or no induction of FS mRNA levels could be detected at 24 or 48 h. Concentration dependence studies performed 8 h after stimulation indicated that the maximal induction occurred with 30-100 ng/ml hCG, with an ED50 of about 3-10 ng/ml. When the cells were treated with the protein synthesis inhibitor cycloheximide (20 micrograms/ml) 20 min before stimulation of the cells with hCG, both basal and hCG-stimulated FS mRNA levels increased at 24 h, indicating stabilization of the transcripts. However, it did not affect the rapid induction of FS mRNA levels by hCG at 2 h. The decline in FS transcript levels in untreated and hCG-treated cells was studied by blocking the transcription with 5 microM actinomycin-D. The degradation rate of FS mRNA was increased in hCG-treated compared to control cells. To study whether the transiently induced FS mRNAs are translated to proteins in hCG-treated and untreated human GL cells, metabolic labeling and immunoprecipitation experiments were performed to detect secreted [35S]FS proteins with the specific anti-FS antiserum Rb 32.(ABSTRACT TRUNCATED AT 400 WORDS)


Assuntos
Gonadotropina Coriônica/farmacologia , Glicoproteínas/análise , Glicoproteínas/genética , Células da Granulosa/química , Células da Granulosa/citologia , RNA Mensageiro/análise , Sequência de Bases , Células Cultivadas , DNA Complementar/análise , DNA Complementar/genética , Relação Dose-Resposta a Droga , Feminino , Folistatina , Células da Granulosa/efeitos dos fármacos , Humanos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Testes de Precipitina , RNA Mensageiro/genética , Fatores de Tempo
15.
J Clin Endocrinol Metab ; 78(6): 1521-4, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8200957

RESUMO

Activins have potent effects on early morphogenetic events during amphibian embryogenesis but no evidence for their role during human development other than their expression in steroidogenic tissues has been reported. We previously showed the expression of the activin type II and IIB receptor mRNAs in several tissues of the mid-gestational human fetus with highest expression levels in developing neural, muscular and exocrine glandular organs. We now report that the mRNA transcripts for activin beta A- and beta B-subunits and for the activin-binding protein follistatin are found co-expressed in several of these extragonadal tissues. Their mRNAs were detected by Northern analyses using specific single-stranded 32P-labeled cDNA probes. In the nervous system, both activin beta A- and beta B-subunit transcripts were expressed in the cerebrum and spinal cord. Follistatin was abundantly expressed in the spinal cord whereas weaker signals where observed in the cerebrum and cerebellum. In the muscular system, beta A-subunit was abundantly expressed in the heart but to a lesser extent in the skeletal muscle while the opposite was observed for follistatin. Follistatin, and activin beta A- and beta B-subunit mRNAs were also detected in developing kidney, salivary gland, liver, and adrenal. The predominance of beta A-subunit mRNAs in the bone marrow and beta B-subunit mRNAs in the salivary gland suggests specific roles for activin A and B, respectively, in these tissues. No hybridization signal was detected for the inhibin alpha-subunit in non-steroidogenic tissues indicating that, in contrast to activins and follistatin, the effects of inhibins may be restricted to the gonads and adrenals which are known to express high levels of the alpha-subunit transcript. Taken together, our results suggest that the activin-follistatin system regulates the development of several organ systems in the mid-gestational human fetus.


Assuntos
Desenvolvimento Embrionário e Fetal , Feto/metabolismo , Glicoproteínas/biossíntese , Inibinas/biossíntese , RNA Mensageiro/análise , Aborto Legal , Ativinas , Sequência de Bases , Northern Blotting , Primers do DNA , Sondas de DNA , Feminino , Folistatina , Idade Gestacional , Substâncias de Crescimento , Humanos , Substâncias Macromoleculares , Masculino , Dados de Sequência Molecular , Especificidade de Órgãos , Gravidez , RNA Mensageiro/biossíntese
16.
Blood ; 83(8): 2163-70, 1994 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-8161782

RESUMO

Recent studies have indicated that activin A/erythroid differentiation factor is a physiologic hematopoietic growth and differentiation factor mainly for cells of the erythroid lineage. We studied the expression of the two type II activin receptor mRNAs during the differentiation of K562 erythroleukemic cells, which are known to be induced toward the erythroid lineage in response to activin or toward the megakaryoblastic lineage by phorbol myristate acetate (PMA). The cDNA of the human activin receptor type IIB (hActR-IIB) was cloned and sequenced from two RNA sources, the K562 cells and the human fetal brain, which is, of the tissues screened by Northern blot analysis, the most abundant source of ActR-IIB RNA. The cDNA encodes a predicted 512 amino acid protein containing an extracellular ligand binding domain, a hydrophobic transmembrane domain, and an intracellular serine/threonine kinase domain. The amino acid sequence is 99.2% and 98.4% homologous in the coding region to the previously described mouse and rat ActR-IIB2s, respectively, and 69% identical to the other human activin serine/threonine kinase receptor, hActR-II. The alternative splicing events in the juxtamembrane region previously reported for the respective mouse receptor were not observed during the processing of K562 cell and human fetal brain RNA. Northern analysis showed that the 10- and 2.5-kb transcripts of hActR-IIB are more abundantly expressed than the 6.0- and 3.0-kb transcripts of hActR-II in K562 cells. No changes in the steady-state levels of hActR-II and IIB mRNAs were detected upon differentiation of K562 cells by activin A or by PMA. Similarly, the receptor mRNA levels remained constant in HL-60 cells induced to either monocyte/macrophage or granulocyte-like cells by PMA or dimethyl sulfoxide, respectively. Thus, the mRNA expression levels of both receptors apparently do not correlate with the differentiation status of these cells.


Assuntos
DNA Complementar/genética , Leucemia Eritroblástica Aguda/metabolismo , Receptores de Fatores de Crescimento/genética , Receptores de Ativinas , Sequência de Aminoácidos , Sequência de Bases , Diferenciação Celular , Clonagem Molecular , Expressão Gênica , Humanos , Leucemia Eritroblástica Aguda/patologia , Dados de Sequência Molecular , RNA Mensageiro/análise , Fator de Crescimento Transformador beta/genética , Células Tumorais Cultivadas
17.
Mol Cell Endocrinol ; 92(2): R15-20, 1993 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8319822

RESUMO

We studied the expression of inhibin/activin subunit mRNAs in granulosa-luteal cells of preovulatory ovarian follicles obtained from women undergoing in vitro fertilization, and in corpus luteum tissue samples of early pregnancy. Northern analysis of granulosa-luteal cell and corpus luteum RNA with single-stranded cDNA or cRNA probes revealed an 1.6-kb mRNA for the alpha subunit and about 6.0-, 4.0-, 2.8-, and 1.7-kb transcripts for the beta A subunit. No clear hybridization signal for the beta B subunit could be detected. The relative expression levels of alpha and beta A subunit mRNAs were determined at 2-day intervals in granulosa-luteal cells cultured for 5 to 11 days. The levels of alpha subunit mRNAs declined steadily with increasing culture age, whereas those of beta A remained unchanged. Reverse transcription-polymerase chain reaction analysis with 35 amplification cycles confirmed the expression of alpha and beta A subunit mRNAs in cultured granulosa-luteal cells. The beta B transcripts were also weakly detectable by this sensitive assay. In situ hybridization of human early pregnancy corpus luteum revealed intense hybridization with the alpha cRNA probe and a weaker signal for the beta A subunit in the granulosa cell compartment. We conclude that: (1) the inhibin alpha and beta A subunits (and to a lesser extent beta B) are expressed in cultured human granulosa-luteal cells; (2) during extended culture periods the alpha/beta A mRNA expression ratio decreases; and that (3) the alpha and beta A subunit mRNA expression is observed in the granulosa cell compartment of early pregnancy corpora lutea.


Assuntos
Corpo Lúteo/metabolismo , Células da Granulosa/metabolismo , Inibinas/biossíntese , Ativinas , Northern Blotting , Células Cultivadas , Corpo Lúteo/citologia , Feminino , Fertilização in vitro , Expressão Gênica , Humanos , Hibridização In Situ , Inibinas/genética , Reação em Cadeia da Polimerase , Gravidez , RNA Mensageiro/genética
18.
Artigo em Inglês | MEDLINE | ID: mdl-2565789

RESUMO

1. Non-invasive methods were developed for measuring mammary blood flow in lactating goats. 2. A Doppler principle ultrasound device was equipped with an external detector measuring maximal blood velocity (Vmax) and average blood velocity (Vav) was calculated as Vmax/2. Volume flow then depended on determination of the angle of insonation and the cross-sectional area of the milk vein (the caudal superficial epigastric or subcutaneous abdominal vein). 3. Blood velocities were measured on the milk vein of either side of the animal while clamping the pudendal veins manually. Blood velocities ranged from 7-34 cm/sec. 4. The milk vein diameter was measured by means of a slide gauge which, for clearly protruding veins, gave similar results to that measured by ultrasound scanning. In protruding veins the cross-section was circular. In non-protruding veins the cross-section was elliptical and the slide gauge significantly (P less than 0.01) overestimated the cross-sectional area. The milk vein diameter of either side measured in 10 lactating goats was 8.8 +/- 1.1 mm (means +/- SD). 5. Blood flow ranged from 90-675 ml/min in a dry and a high-yielding (3.4 l milk daily) goat, respectively. The reproducibility of the blood flow measurements was 12-16%. 6. It is concluded that the present method may be used for quantitative measurements of mammary blood flow in goats.


Assuntos
Cabras/fisiologia , Lactação/fisiologia , Glândulas Mamárias Animais/irrigação sanguínea , Animais , Velocidade do Fluxo Sanguíneo , Feminino , Gravidez , Ultrassom
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