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1.
Biol Reprod ; 100(2): 390-397, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30304517

RESUMO

Cell fusion is involved in the development of some adult organs, is implicated in the pathogenesis of specific types of cancer, and is known to participate in repair/regeneration processes mediated by bone-marrow-derived cells (BMDCs). Endometriosis is a disease characterized by growth of functional endometrial tissue outside of the uterine cavity. Endometriosis shares some molecular properties with cancer and BMDCs home to endometriosis lesions in a mouse model. Our objective was to determine if cell fusion can occur in endometriosis and establish whether bone-marrow-derived cells participate in cell fusion events in lesions. We employed a Cre-Lox system to identify cell fusion events in a mouse model of endometriosis. Fused cells were detected in endometriotic lesions, albeit at a low frequency (∼1 in 400 cells), localized to the stromal compartment, and displayed restricted proliferation. Using 5-fluorouracil-based nongonadotoxic bone marrow transplantation model, we demonstrate that bone marrow cells represent a principal cell source for fusion events in lesions. Cell fusion progeny uniformly lacked expression of selected markers of hematopoietic, endothelial, and epithelial markers, though they expressed the mesenchymal/stromal markers Sca-1 and CD29. This study is the first to describe the phenomenon of cell fusion in endometriosis and points to a mesenchymal population derived from cell fusion events with limited proliferative activity, properties previously attributed to endometrial stem cells. Their putative role in the pathogenesis of the disease remains to be elucidated.


Assuntos
Fusão Celular , Endometriose/patologia , Animais , Modelos Animais de Doenças , Endométrio/citologia , Feminino , Citometria de Fluxo , Camundongos , Mutação
2.
J Dairy Sci ; 95(4): 1729-37, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22459821

RESUMO

Ovarian follicular cysts and persistent follicles are follicular pathologies involved in reduced fertility of dairy cows. Two separate experiments were performed on high-yielding Holstein cows to characterize ovarian cyclicity and evaluate the developmental dynamics of follicle pathologies postpartum. In experiment 1, 58 cows were monitored by ultrasonography twice weekly from d 18±1 to 69±2 postpartum. First ovulation occurred 38±3, 27±2, 20±1, and 25±3 d postpartum in cows with 1 cycle (n=11), 2 cycles (n=21), 3 cycles (n=13), and 4 cycles (n=7), respectively. Follicular pathologies were developed in cows that were either acyclic (n=6) or had 1 or 2 cycles, but not in cows with more than 2 cycles. In experiment 2, 47 cows were monitored twice weekly from 10 d postpartum to second ovulation. Follicles ≥17 mm in diameter in 2 consecutive scans were aspirated, and concentrations of various hormones were measured. Cows were defined as cyclic (n=30; 64%) or with the potential to develop follicular pathology (n=17; 36%). Aspirated follicles (n=27) were classified into 3 main groups based on follicular growth rate, follicular diameter, and ovarian activity before and after follicular aspiration. Dominant follicles (n=4) were defined as large follicles (20 mm in diameter) with growth rate ≤1 mm/d and normal ovarian activity. Persistent follicles (n=6) had the same growth rate and diameter as the dominant follicles, but persisted at the same diameter for ≥10 d. Ovarian cysts (n=17) were defined as the largest follicular structures (19 to 32 mm in diameter), with abnormal growth rate (>1 mm/d) and abnormal ovarian activity. Single or turnover cysts did not differ in their growth parameters and were therefore combined and further classified according to follicular-fluid hormone concentrations. Estradiol-dominant cysts (n=7) were characterized by normal estradiol (284 to 659 ng/mL) and progesterone (20 to 113 ng/mL) concentrations, similar to those of the dominant follicle (554 to 993 ng/mL and 44 to 106 ng/mL, respectively). Progesterone-dominant cysts (n=5) were characterized by low estradiol (0.06 to 330 ng/mL) and high progesterone (586 to 3,288 ng/mL) concentrations. Low-steroidogenic active cysts (n=5) were characterized by low concentrations of both estradiol (23 to 61 ng/mL) and progesterone (17 to 205 ng/mL). Characterization of spontaneously forming cysts might enable definition of the formation of ovarian follicular pathologies in postpartum cows.


Assuntos
Doenças dos Bovinos/patologia , Líquido Folicular/química , Hormônios/análise , Cistos Ovarianos/veterinária , Folículo Ovariano/patologia , Transtornos Puerperais/veterinária , Animais , Bovinos , Doenças dos Bovinos/diagnóstico por imagem , Doenças dos Bovinos/etiologia , Estradiol/análise , Feminino , Cistos Ovarianos/etiologia , Cistos Ovarianos/patologia , Folículo Ovariano/diagnóstico por imagem , Folículo Ovariano/fisiopatologia , Progesterona/análise , Progesterona/sangue , Transtornos Puerperais/etiologia , Transtornos Puerperais/patologia , Ultrassonografia
3.
J Neurosurg Anesthesiol ; 34(4): 429-436, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34127616

RESUMO

BACKGROUND: Volatile anesthetic exposure during development leads to long-term cognitive deficits in rats which are dependent on age and sex. Female rats are protected relative to male rats for the same exposure on postnatal day 7. Here we test our hypothesis that androgens can modulate chloride cotransporter expression to alter the susceptibility to neurotoxicity from GABAergic drugs using female rats with exogenous testosterone exposure. METHODS: Female rats were injected with testosterone (100 µg/animal) or vehicle on postnatal days 1 to 6. On postnatal day 7, the animals were randomized to either isoflurane exposure or sham. Spatial memory was assessed with the Barnes maze starting on postnatal day 41. Western blots were run from testosterone treated postnatal day 7 animals to measure levels of chloride cotransporters sodium-potassium-chloride symporter (NKCC1) and chloride-potassium symporter 5 (KCC2). RESULTS: Exogenous testosterone modulated isoflurane anesthetic neurotoxicity in female rats based on poor performance in the probe trial of the Barnes Maze. By contrast, females with vehicle and isoflurane exposure were able to differentiate the goal position. These behavioral differences corresponded to differences in the protein levels of NKCC1 and KCC2 after exogenous testosterone exposure, with NKCC1 increasing ( P <0.001) and KCC2 decreasing ( P =0.003) relative to female controls. CONCLUSIONS: The expression of chloride cotransporters, NKCC1 and KCC2, is altered by testosterone in female rats and corresponds to a cognitive deficit after isoflurane exposure. This confirms the role of androgens in perinatal anesthetic neurotoxicity and supports our hypothesis that the developing GABAergic system plays a critical role in the underlying mechanism.


Assuntos
Anestésicos , Isoflurano , Simportadores , Animais , Feminino , Masculino , Gravidez , Ratos , Androgênios , Animais Recém-Nascidos , Cloretos , Isoflurano/toxicidade , Ratos Sprague-Dawley , Membro 2 da Família 12 de Carreador de Soluto/metabolismo , Simportadores/metabolismo , Testosterona
5.
Science ; 228(4695): 21-6, 1985 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-17811549

RESUMO

A strain of Saccharomyces cerevisiae capable of simultaneous hydrolysis and fermentation of highly polymerized starch oligosaccharides was constructed. The Aspergillus awamori glucoamylase enzyme, form GAI, was expressed in Saccharomyces cerevisiae by means of the promoter and termination regions from a yeast enolase gene. Yeast transformed with plasmids containing an intron-free recombinant glucoamylase gene efficiently secreted glucoamylase into the medium, permitting growth of the transformants on starch as the sole carbon source. The natural leader sequence of the precursor of glucoamylase (preglucoamylase) was processed correctly by yeast, and the secreted enzyme was glycosylated through both N- and O-linkages at levels comparable to the native Aspergillus enzyme. The data provide evidence for the utility of yeast as an organism for the production, glycosylation, and secretion of heterologous proteins.

6.
Pathobiology ; 75(6): 346-55, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19096230

RESUMO

BACKGROUND: One strategy to increase tissue specificity of gene therapy is to use promoters or enhancers. OBJECTIVES: (1) To enhance the selectivity of a murine preproendothelin-1 (PPE-1) promoter in tumor angiogenesis by using a positive endothelial transcription-binding element. (2) To test the specificity and efficiency of the modified PPE-1 promoter [PPE-1(3X)] in vitro and in vivo by using reporter genes, and the therapeutic gene herpes simplex virus-thymidine kinase (HSV-TK) in a mouse model of Lewis lung carcinoma (LLC). RESULTS: The modified PPE-1 promoter specifically induced expression in the tumor angiogenic vascular bed with a 35-fold higher expression compared to the normal vasculare bed of the lung. Thus, when the HSV-TK gene controlled by the modified PPE-1 promoter was used systemically, it induced tumor-specific necrosis, apoptosis and mononuclear infiltrates, leading to massive destruction of the neovasculature of the pulmonary metastasis, which suppressed metastasis development. CONCLUSIONS: These results show that an adenoviral vector armed with HSV-TK controlled by the endothelial-selective murine PPE-1(3X) promoter is efficient and safe to target tumor neovasculature.


Assuntos
Carcinoma Pulmonar de Lewis/terapia , Endotelina-1/genética , Terapia Genética/métodos , Neovascularização Patológica/terapia , Regiões Promotoras Genéticas , Simplexvirus/enzimologia , Timidina Quinase/genética , Adenoviridae/genética , Animais , Carcinoma Pulmonar de Lewis/irrigação sanguínea , Endotélio Vascular/metabolismo , Genes Virais/genética , Vetores Genéticos , Pulmão/irrigação sanguínea , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Simplexvirus/genética , Timidina Quinase/metabolismo
7.
Theriogenology ; 70(6): 956-67, 2008 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-18602682

RESUMO

The effect of intramammary (IMM) or intravenous (IV) administration of E. coli endotoxin (LPS), at the onset of estrus, at the time of ovulation was examined. Steroid and gonadotropin concentrations around ovulation were also determined. Lactating Holstein cows (n=33) were assigned to saline-controls (n=12) and treated with LPS-IV (0.5 microg/kg; n=13) or LPS-IMM (10 microg; n=8). Synchronized cows were observed continuously for estrus. LPS (or saline) was injected within 30 min from the onset of standing estrus, at peak estradiol concentrations. The typical rise of body temperature, somatic cell count, cortisol, and NAGase activity was noted. One-third of both LPS-IV- and LPS-IMM-treated cows were manifested by an extended estrus to ovulation (E-O) interval of around 75 h or did not ovulate, compared with about 30 h in the other 2/3 of LPS cows and all controls. Estradiol concentrations 24 h before and after LPS did not differ between groups. However, LPS-IV cows with extended intervals exhibited another estrus and an additional rise of estradiol followed by delayed ovulation. LPS-treated cows with a delayed E-O interval had low or delayed LH surge; two LPS-treated cows did not exhibit LH surge and did not ovulate. All control cows exhibited normal hormone levels. Delayed ovulation was associated with a delayed rise of luteal progesterone. The results indicated that exposing cows to endotoxin during estrus induced a decreased and delayed LH surge in one-third of the cows. This was associated with delayed ovulation, which reduces the chances of successful fertilization.


Assuntos
Bovinos/fisiologia , Endotoxinas/farmacologia , Ciclo Estral/efeitos dos fármacos , Hormônios/sangue , Ovulação/efeitos dos fármacos , Animais , Bovinos/sangue , Endotoxinas/administração & dosagem , Escherichia coli , Estradiol/sangue , Ciclo Estral/sangue , Feminino , Hidrocortisona/sangue , Injeções Intradérmicas , Injeções Intravenosas , Lipopolissacarídeos/administração & dosagem , Lipopolissacarídeos/farmacologia , Hormônio Luteinizante/sangue , Glândulas Mamárias Animais/efeitos dos fármacos , Ovulação/fisiologia , Fatores de Tempo
8.
Mol Cell Biol ; 4(11): 2306-15, 1984 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-6440004

RESUMO

The filamentous ascomycete Aspergillus awamori secretes large amounts of glucoamylase upon growth in medium containing starch, glucose, or a variety of hexose sugars and sugar polymers. We examined the mechanism of this carbon source-dependent regulation of glucoamylase accumulation and found a several hundredfold increase in glucoamylase mRNA in cells grown on an inducing substrate, starch, relative to cells grown on a noninducing substrate, xylose. We postulate that induction of glucoamylase synthesis is regulated transcriptionally. Comparing total mRNA from cells grown on starch and xylose, we were able to identify an inducible 2.3-kilobase mRNA-encoding glucoamylase. The glucoamylase mRNA was purified and used to identify a molecularly cloned 3.4-kilobase EcoRI fragment containing the A. awamori glucoamylase gene. Comparison of the nucleotide sequence of the 3.4-kilobase EcoRI fragment with that of the glucoamylase I mRNA (as determined from molecularly cloned cDNA) revealed the existence of four intervening sequences within the glucoamylase gene. The 5' end of the glucoamylase mRNA was mapped to several locations within a region -52 to -73 nucleotides from the translational start. Sequence and structural features of the glucoamylase gene of the filamentous ascomycete A. awamori were examined and compared with those reported in genes of other eucaryotes.


Assuntos
Aspergillus/genética , Genes Fúngicos , Glucana 1,4-alfa-Glucosidase/genética , Glucosidases/genética , Sequência de Bases , Clonagem Molecular , Regulação da Expressão Gênica , RNA Fúngico/genética , RNA Mensageiro/genética
9.
Exp Clin Endocrinol Diabetes ; 114(3): 95-104, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16636974

RESUMO

Single chain variants of the heterodimeric gonadotropins were engineered by tethering the genes of the individual subunits into one polypeptide. In tethered human (h) gonadotropins, the carboxyl terminal peptide (CTP) of the choriogonadotropin (CG) beta subunit serves as an effective linker to enhance the secretion of the analogs compared to variants lacking the CTP. The gonadotropin subunits of non-primate, non-equid species lack a CTP domain that precludes the use of a homologous CTP in tethered analogs in many species. Here we used the bovine LH as a model to examine the impact of the CTP domain of the hCGbeta subunit (denoted as huCTP) and of a previously untranslated CTP-like sequence decoded from the bovine LHbeta gene on the secretion and bioactivity of tethered analogs. This cryptic CTP (designated boCTP) was incorporated into the bovine LHbeta reading frame by deletion frame-shift mutations analogous to these that presumably occurred in primates and equids. We genetically engineered single chain variants in which the beta and alpha subunit domains were linked directly or via the heterologous huCTP or the homologous boCTP sequences and expressed them in CHO cells. The data suggest that the tethered analogs were expressed and N-glycosylated, but unlike the huCTP, the boCTP appears as devoid of mucin O-glycans. The incorporation of the boCTP or huCTP linkers enhanced by about 3fold the rate and efficiency of secretion from the transfected cells. The tether variants were bioactive, as estimated by induction of steroid production in immortalized granulosa cells expressing the rat LH receptor. Furthermore, the variants were about equally potent, as judged by their EC50s (0.7-0.9 ng/ml). Thus, the hCGbeta CTP maintains pro-secretory determinants without inhibiting receptor activation when applied as a linker in tethered bovine LH, implying that these CTP features are preserved when the domain is incorporated into non-primate single chain analogs. The study suggests that the boCTP and huCTP domains are advantageous for the secretion of tethered bovine gonadotropins, and also demonstrates strategies for the design of bioactive LH analogs in ruminant species.


Assuntos
Gonadotropina Coriônica/genética , Gonadotropina Coriônica/metabolismo , Hormônio Luteinizante/genética , Hormônio Luteinizante/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Células CHO , Bovinos , Cricetinae , Feminino , Variação Genética , Glicosilação , Células da Granulosa/metabolismo , Humanos , Dados de Sequência Molecular , Engenharia de Proteínas , Processamento de Proteína Pós-Traducional , Ratos , Transfecção
10.
J Dairy Sci ; 89(12): 4694-702, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17106102

RESUMO

Short fertile half-lives of the male and female gametes in the female tract necessitate accurate timing of artificial insemination. We examined the possible association between extension of the estrus to ovulation (E-O) interval and alterations in concentrations of estradiol, progesterone, and the preovulatory LH surge before estrus and ovulation. High-yielding Holstein cows (n = 74 from a total of 106) were synchronized and were examined around the time of the subsequent estrus. They were observed continuously for estrual behavior. Blood samples were collected before and after estrus, and ultrasound checks for ovulation were made every 4 h. About three-quarters of the cows exhibited short (but normal) E-O intervals of 22 to 25 h (25%) or normal intervals of 25 to 30 h (47%); 17% of them displayed a long (but normal) E-O interval of 31 to 35 h, and about 10% exhibited a very long E-O interval of 35 to 50 h. Extended E-O interval comprised estrus-to-LH surge and LH surge-to-ovulation intervals that were both longer than normal. Pronounced changes in hormonal concentrations were noted before ovulation in the very long E-O interval group of cows: progesterone and estradiol concentrations were reduced, and the preovulatory LH peak surge was markedly less than in the other 3 groups. Postovulation progesterone concentrations during the midluteal phase were lesser in the very long and the long E-O interval groups compared with those in the short and normal interval groups. Season, parity, milk yield, and body condition did not affect the estrus to LH surge, LH surge to ovulation, and E-O intervals. The results indicate an association between preovulatory-reduced estradiol concentrations and a small preovulatory LH surge, on the one hand, and an extended E-O interval, on the other hand. Delayed ovulation could cause nonoptimal timing of AI, a less than normal preovulatory LH surge that may be associated with suboptimal maturation of the oocyte before ovulation, or reduced progesterone concentrations before and after ovulation. All may be factors associated with poor fertility in cows with a very long E-O interval.


Assuntos
Bovinos/fisiologia , Estro/fisiologia , Ovulação/fisiologia , Animais , Indústria de Laticínios , Estradiol/sangue , Feminino , Hormônio Luteinizante/sangue , Hormônio Luteinizante/fisiologia , Progesterona/sangue , Fatores de Tempo
11.
Int J Impot Res ; 17(2): 186-90, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15510189

RESUMO

The long-term effect of treatment with continuous positive airway pressure (CPAP) on erectile function was assessed in 60 patients with obstructive sleep apnea syndrome (OSAS). Severity of OSAS was evaluated by respiratory disturbance index (RDI) and minimal oxygen saturation (OxiMin). Severity of erectile dysfunction (ED) was assessed with the five question International Index of Erectile Function (IIEF-5) before and after CPAP treatment. Subjects were categorized into three groups on the basis of the change in IIEF-5 score: Group 1, no change (n=37); Group 2, improvement from 10+/-5.65 to 19.1+/-5.7, P<0.01 (n=12); Group 3, worsening from 19.9+/-4.7 to 9.5+/-7.8, P<0.01 (n=11). Group 2 had significantly higher RDI and lower OxiMin than the other groups, and was also more compliant and satisfied with CPAP. Change in IIEF-5 with CPAP treatment was negatively correlated (Pearson coefficient) with OxiMin (r=-0.374), and positively correlated with adherence to CPAP treatment (r=0.689). In conclusion, in selected patients, CPAP treatment for OSAS may by itself have a positive effect on erectile function by improving respiration during sleep. Predictors of erectile improvement include high RDI, low OxiMin, and CPAP compliance.


Assuntos
Pressão Positiva Contínua nas Vias Aéreas , Ereção Peniana/fisiologia , Apneia Obstrutiva do Sono/terapia , Adulto , Idoso , Disfunção Erétil/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Cooperação do Paciente , Inquéritos e Questionários
12.
Domest Anim Endocrinol ; 53: 52-9, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26099839

RESUMO

Ovulation failure, follicular persistence, and formation of follicular cysts are known to impair dairy cow fertility. Although the underlying mechanism is not entirely clear, stress-induced alteration in adrenal hormone secretion can cause these ovarian pathologies. Six synchronized lactating cows were scanned daily by ultrasound, and plasma samples were taken throughout the estrous cycle. Treatment cows (n = 3) were administered with ACTH analog every 12 h from day 15 to day 21 of the cycle to induce formation of follicular cysts. Ovaries were collected at the slaughterhouse on day 23 of the cycle before appearance of follicular pathologies. Control cows (n = 3) were administered placebo, resynchronized, and administered PGF2α on day 6 of the new cycle to induce development of a preovulatory follicle. Follicular fluid was aspirated from the preovulatory follicles of each group to determine their steroid milieu. Slices were taken from the follicular wall for total messenger (m) RNA isolation and semiquantitative reverse transcription polymerase chain reaction (RT-PCR). Administration of ACTH increased (P < 0.02) plasma cortisol concentration and reduced (P < 0.01) milk production. Androstenedione and estradiol concentrations in the follicular fluids were lower (P < 0.05) in ACTH-treated follicles than those in controls. The mRNA expression of luteinizing hormone receptor, 3ß-hydroxysteroid dehydrogenase, cytochrome P450 aromatase (P450arom), and cytochrome P450 17α-hydroxylase (P450c17) were lower (P < 0.02) in the ACTH-treated vs control cows. On the other hand, the expression of steroidogenic acute regulatory protein and cytochrome P450 side-chain cleavage did not differ between groups. In addition, mRNA expression of vascular endothelial growth factor (VEGF)120 and VEGF164 was higher (P < 0.01) in control than in ACTH-treated follicles, but that for angiopoietin-1 and 2 did not differ between groups. Findings indicated that ACTH administration throughout preovulatory follicle development alters follicular steroidogenesis in association with impaired angiogenesis. Such alterations might explain, in part, the mechanism underlying ovulation failure and the formation of persistent or cystic follicles under stress.


Assuntos
Hormônio Adrenocorticotrópico/farmacologia , Neovascularização Fisiológica/fisiologia , Ovulação/fisiologia , Esteroides/metabolismo , Androstenodiona/sangue , Animais , Bovinos , Estradiol/sangue , Feminino , Fase Folicular , Regulação da Expressão Gênica , Lactação/efeitos dos fármacos , Folículo Ovariano , Progesterona/sangue , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
13.
Protein Sci ; 7(8): 1671-80, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10082364

RESUMO

Activated Factor X releases F1.2, a 271-amino acid peptide, from the amino terminus of prothrombin during blood coagulation. A nine-amino acid peptide, C9 (DSDRAIEGR), corresponding to the carboxyl terminus of F1.2 was synthesized and used to produce a monoclonal antibody, TA1 (K(D)) 1.22 x 10(-6) M). To model the TA1 antibody, we entered the sequence information of the cloned TA1 Fv into the antibody modeling program, ABM, which combines homology methods, conformational search procedures, and energy screening and has proved to be a reliable and reproducible antibody modeling method. Using a novel protein fusion procedure, we expressed the C9 peptide fused to the carboxyl terminus of the PENI repressor protein from Bacillus licheniformis in Escherichia coli. We constructed fusion proteins containing alanine substitutions for each amino acid in the C9 epitope. Binding studies, using the C9 alanine mutants and TA1, and spatial constraints predicted by the modeled TA1 binding cleft enabled us to establish a plausible conformation for C9 complexed with TA1. Furthermore, based on binding results of conservative amino acid substitutions in C9 and mutations in the antibody, we were able to refine the complex model and identify antibody mutations that would improve binding affinity.


Assuntos
Anticorpos/química , Simulação por Computador , Modelos Moleculares , Mutagênese Sítio-Dirigida , Ligação Proteica , Alanina/química , Aminoácidos/química , Bacillus/metabolismo , Ligação Competitiva , Western Blotting , Escherichia coli/metabolismo , Ligação de Hidrogênio , Transportador 1 de Aminoácidos Neutros Grandes , Proteínas de Membrana/imunologia , Oligonucleotídeos , Proteínas Recombinantes de Fusão
14.
J Mol Endocrinol ; 13(3): 253-64, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7893343

RESUMO

The aim of the present study was to investigate the sites and time of follistatin and inhibin alpha and beta A subunit gene expression during ovine follicular development and atresia. Prepubertal ovaries of 2-, 8- and 14-week-old ewe lambs (n = 9) were used. Regardless of age, the ovaries contained many follicles at different stages of development up to 2 mm in diameter, but large antral follicles were not found. Ovarian sections were hybridized with 35S-labelled antisense RNA probes transcribed from follistatin, inhibin alpha or inhibin beta A cDNA. Ovaries from mature gonadotrophin-stimulated ewes were used as controls. All three probes hybridized exclusively to granulosa cells, and not to other follicular or stromal cells. None of the probes hybridized to primordial follicles or primary follicles with less than two layers of granulosa cells. Follistatin mRNA was expressed strongly in the granulosa cells of all preantral follicles with two or more layers of cells, and in all non-atretic antral follicles. In addition, follistatin mRNA was found in some cells of the ovarian rete tubules. The inhibin alpha riboprobe hybridized to the granulosa cells of most preantral and all non-atretic antral follicles. In the preantral follicles, the strongest inhibin alpha expression was observed in the cells that were in close proximity to the oocyte. The inhibin beta A riboprobe hybridized exclusively to the granulosa cells of antral follicles. The labelling was observed either in the cumulus oophorus or in the cumulus oophorus and periantral granulosa cells of the non-atretic antral follicles. In adult ovaries, which were used as controls, the inhibin beta A riboprobe hybridized strongly to all granulosa cells of non-atretic large antral follicles. During follicular atresia, expression of all three mRNAs progressively decreased. In early atresia, inhibin beta A mRNA was observed only in the cells of the cumulus, whereas inhibin alpha and follistatin mRNAs were still present in the granulosa cells. As atresia progressed mRNA for inhibin alpha, and later also follistatin, disappeared. Our results suggest that there is a sequential appearance and disappearance of follistatin, inhibin alpha and inhibin beta A mRNAs during follicular development and atresia respectively. The marked expression of inhibin beta A in the cumulus cells implies a role of the oocyte in the differentiation of these cells.


Assuntos
Atresia Folicular/metabolismo , Glicoproteínas/genética , Inibinas/genética , Folículo Ovariano/fisiologia , Ovário/metabolismo , Ativinas , Animais , Feminino , Folistatina , Glicoproteínas/biossíntese , Células da Granulosa/metabolismo , Hibridização In Situ , Inibinas/biossíntese , Ovário/citologia , RNA Mensageiro/biossíntese , Ovinos/fisiologia , Transcrição Gênica
15.
J Mol Endocrinol ; 13(1): 1-9, 1994 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7999251

RESUMO

The aim of this study was to investigate the sites of follistatin and alpha and beta A inhibin mRNA expression in the ovaries of female sheep fetuses at 90, 100, 120 and 135 days of gestation (term = day 147). At 90 and 100 days primordial follicles were formed, followed by the appearance of primary follicles at 100 days of gestation. At days 120 and 135, primordial, primary and preantral (i.e. secondary) follicles were present in the ovaries, but antral (i.e. tertiary) follicles were not observed at any of these gestational ages. Two Booroola genotypes were studied: homozygous carriers (BB) and non-carriers (++) of the fecundity gene (FecB). Irrespective of genotype no specific hybridization of the alpha and beta A inhibin riboprobes was detected in any ovarian cells at days 90, 100, 120 or 135 of gestation. In control mature ovaries, on the other hand, strong hybridization in the granulosa cells of antral follicles was observed. In contrast to alpha and beta A inhibin, follistatin antisense (but not sense) riboprobes hybridized specifically to the granulosa cells of preantral follicles with two or more layers of cells at days 120 and 135 of gestation. Moreover, hybridization was also evident in the cells of the ovarian rete at days 120 and 135, but not at 90 or 100 days. No follistatin mRNA expression was observed in the granulosa cells of primordial or primary follicles or in any other ovarian cell type at any of the gestational ages examined.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Feto/metabolismo , Glicoproteínas/genética , Inibinas/genética , Ovário/metabolismo , Peptídeos/genética , Proteínas Secretadas pela Próstata , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Animais , Feminino , Fertilidade/genética , Folistatina , Expressão Gênica , Idade Gestacional , Células da Granulosa/metabolismo , Homozigoto , Hibridização In Situ , Ovário/citologia , Ovário/embriologia , Gravidez , Ovinos
16.
AIDS Res Hum Retroviruses ; 10(8): 939-46, 1994 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7529032

RESUMO

A number of structurally diverse compounds have been shown to be potent inhibitors of the DNA polymerase activity of human immunodeficiency virus (HIV-1) reverse transcriptase (RT). The compounds can be grouped into two broad classes: nucleoside analogs and nonnucleoside inhibitors. The nonnucleoside inhibitors are quite specific for the polymerase activity of HIV-1 RT; they do not affect the polymerase activity of HIV-2 RT or the ribonuclease H (RNase H) activity of either HIV-1 RT or HIV-2 RT. Structural, biochemical, and genetic analyses showed that this group of inhibitors binds in a hydrophobic pocket near the polymerase active site. Mutations in amino acids that line this hydrophobic pocket, for example at tyrosine 181, tyrosine 188, or lysine 103, lead to enzymes that are resistant to the nonnucleoside inhibitors. We have investigated the enzymatic properties of two mutants of HIV-1 RT in which residues 181 and 188 were replaced by the corresponding amino acids in HIV-2 RT (tyrosine 181-->isoleucine and tyrosine 188-->leucine). The two tyrosine mutants closely resemble the wild-type HIV-1 RT in almost all the catalytic functions tested, including the heat stability, sensitivity of the DNA polymerase activity to inhibition by deoxynucleoside analogs, inhibition by the zinc chelator o-phenanthroline, and the Km values calculated for the DNA polymerase activity. There is, however, a slight difference in the effect of orthophenanthroline on the RNase H activity. In addition, there is a subtle disparity in the fidelity of DNA synthesis (analyzed by a mispair extension assay), thus indicating that these mutant RTs are not likely to confer any selective advantages or disadvantages to the variant virions over wild-type virus.


Assuntos
HIV-1/enzimologia , Mutação/fisiologia , Piridinas/farmacologia , DNA Polimerase Dirigida por RNA/metabolismo , Sequência de Aminoácidos , Sequência de Bases , Sítios de Ligação , Catálise , DNA Viral/biossíntese , Nucleotídeos de Desoxiguanina/farmacologia , Didesoxinucleotídeos , Resistência Microbiana a Medicamentos , Transcriptase Reversa do HIV , HIV-1/efeitos dos fármacos , Temperatura Alta , Humanos , Cinética , Dados de Sequência Molecular , Nevirapina , Fenantrolinas/farmacologia , DNA Polimerase Dirigida por RNA/química , DNA Polimerase Dirigida por RNA/genética , Inibidores da Transcriptase Reversa , Ribonuclease H/metabolismo , Moldes Genéticos , Nucleotídeos de Timina/farmacologia , Tirosina/fisiologia , Zidovudina/análogos & derivados , Zidovudina/farmacologia
17.
Nutr Metab ; 23(3): 172-8, 1979.
Artigo em Inglês | MEDLINE | ID: mdl-424085

RESUMO

Serum 25-hydroxycholecalciferol (25[OH]D3) levels and other parameters of vitamin D nutriture were examined in 58 subjects aged 70 or more, living in Jerusalem. They were compared with those of 54 young adults living in the same neighbourhood. No evidence was obtained of a lower level of vitamin D nutriture in the elderly compared to younger adults. Serum 25 (OH)D3 of the elderly adults was 18.4 (SEM: 1.4) ng/ml and in the younger adults, 17.8 (1.0) ng/ml. There was no seasonal variation in serum 25(OH)D3, nor could a strong association be found between reported vitamin D intake nor with exposure to sunshine. There was a negative correlation between serum alkaline phosphatase and the calcium-phosphorus product in serum. High values of alkaline phosphatase were associated with reported low exposure to sunlight and, in elderly persons, with a reported low consumption of vitamin D.


Assuntos
Fosfatase Alcalina/sangue , Cálcio/sangue , Hidroxicolecalciferóis/sangue , Inquéritos Nutricionais , Fósforo/sangue , Vitamina D , Adulto , Fatores Etários , Idoso , Feminino , Fraturas do Colo Femoral/sangue , Humanos , Israel , Masculino , Osteoporose/sangue , Estações do Ano , Luz Solar
18.
Surg Endosc ; 16(5): 785-8, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-11997822

RESUMO

BACKGROUND: This study reviewed our experience with laparoscopic ventral postoperative (incisional) hernia repair. METHODS: Clinical data from the first 100 cases were analyzed retrospectively. RESULTS: Between 1997 and 2000, 64 women and 36 men (mean age, 58.4 +/- 13.6 years; range, 27-87 years) underwent laparoscopic hernioplasty. Hernias (mean diameter, 6.2 +/- 3.7 cm) were in a midline (74%), subcostal (10%), or other incision location, and were recurrent in 25%, of the patients. The mean operative time was 119 +/- 77 min. Extensive adhesiolysis was necessary in 37 cases. There was no mortality. The recorded complications included inadvertent enterotomies (n = 6), seromas (n = 11), prolonged ileus (n = 4), and prolonged fever (n = 3). Seven cases were converted; to repair accidental enterotomies (n = 4) due to difficult adhesiolysis (n = 2), or to control bleeding (n = 1). Six patients underwent reoperation because of enetric leak (n = 3) or bowel obstruction (n = 3). There were two documented recurrences (2%). The mean follow-up period was 19 months (range, 12-54 months). CONCLUSIONS: Laparoscopic intraperitoneal approach to postoperative ventral (incisional) hernia repair may be associated with significant complications and morbidity, which can be prevented in part by meticulous technique and liberal conversions. The justification of this procedure is the low recurrence rate, according to preliminary results.


Assuntos
Hérnia Ventral/etiologia , Hérnia Ventral/cirurgia , Laparoscopia/efeitos adversos , Laparoscopia/métodos , Peritônio/cirurgia , Politetrafluoretileno/uso terapêutico , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Telas Cirúrgicas , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Obstrução Intestinal/etiologia , Obstrução Intestinal/cirurgia , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Politetrafluoretileno/efeitos adversos , Recidiva , Reoperação/métodos , Estudos Retrospectivos , Telas Cirúrgicas/efeitos adversos , Falha de Tratamento , Resultado do Tratamento
19.
Reprod Fertil Dev ; 4(2): 231-7, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1438952

RESUMO

Pituitary response to exogenous gonadotrophin-releasing hormone (GnRH) was examined at a late stage of pregnancy in 10 Booroola-Assaf ewes heterozygous at the FecB locus (FecBFec+) and in 11 Assaf ewes that were non-carriers (Fec+Fec+). Basal plasma luteinizing hormone (LH) and follicle stimulating hormone (FSH) concentrations were similar in the two genotypes. Administration of 100 micrograms of GnRH resulted in a significant increase (P < 0.05) in plasma LH and FSH concentrations in most of the ewes treated. Maximal responses were observed 105-135 min after GnRH treatment. Pituitary responses to GnRH were significantly lower (P < 0.05) in Booroola-Assaf than in Assaf ewes. The decreased pituitary responsiveness observed in FecB gene carriers compared with Fec+Fec+ ewes might be due to differences in the concentrations of ovarian or uterine hormones modulating the release of gonadotrophin. The results suggest that FecB-specific differences can be observed at the pituitary level.


Assuntos
Hormônio Liberador de Gonadotropina/farmacologia , Hipófise/efeitos dos fármacos , Animais , Feminino , Hormônio Foliculoestimulante/sangue , Hormônio Foliculoestimulante/metabolismo , Genótipo , Heterozigoto , Hormônio Luteinizante/sangue , Hormônio Luteinizante/metabolismo , Hipófise/metabolismo , Gravidez , Ovinos , Especificidade da Espécie
20.
Reprod Fertil Dev ; 9(8): 825-32, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9733067

RESUMO

The aim of the present study was to characterize gene and protein expression of follistatin, inhibin alpha (alpha) and inhibin betaA (betaA) subunits in the ovaries of postnatal (3-week-old) and prepubertal (14 and 20-25-week-old) lambs. Northern blot analysis revealed the presence of two alpha and two betaA mRNAs. In postnatal ovary the a 1.2-kb transcript was abundant, its amount gradually falling, while the 2.0-kb mRNA increased and became a major band at 20-25 weeks. Both betaA mRNAs, 4.5 kb and 6.0-7.5 kb, were weakly expressed in postnatal ovary, but whereas the 4.5-kb mRNA expression remained at a low level, that of the 6.0-7.5 kb mRNA increased about five fold in prepubertal ovary. The ratio of total alpha mRNAs to the dominant betaA form (6.0-7.5 kb) varied from 1.27 at 3 weeks to 0.33 at 20-25 weeks of age. One major follistatin mRNA of 2.5-3.6 kb was recognized and was constitutively expressed during ovarian growth. Several molecular-mass forms of alpha and betaA subunits with different compositions were seen in prepubertal compared with postnatal ovaries, the latter exhibiting more active follicular growth. In summary, ovine ovaries undergo distinct changes early in life, both morphological and functional, and show a changing pattern of inhibin subunit expression.


Assuntos
Animais Recém-Nascidos/metabolismo , Inibinas/biossíntese , Ovário/metabolismo , Peptídeos/metabolismo , Proteínas Secretadas pela Próstata , Ovinos/metabolismo , Animais , Northern Blotting , Feminino , Hormônio Foliculoestimulante/sangue , Folistatina , Glicoproteínas/metabolismo , Substâncias de Crescimento/metabolismo , Inibinas/sangue , Ovariectomia , RNA Mensageiro/metabolismo
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