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1.
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
2.
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
4.
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
5.
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
6.
Theriogenology ; 72(5): 690-8, 2009 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-19559473

RESUMO

We examined the hormonal and morphologic changes associated with ovarian cyst formation in high-yielding dairy cows. Follicle fluid was aspirated from 90 cysts and 15 preovulatory and 18 subordinate follicles and used for hormonal determination. Pieces of cystic wall were subjected to morphologic and immunohistochemical evaluation. Cysts were characterized by low concentrations of insulin, insulin-like growth factor-I (IGF-I), and glucose and high activity of IGF binding proteins (IGFBPs). Insulin and IGF-I levels were (mean+/-SEM) 205+/-22 pg/mL and 146+/-42 ng/mL in preovulatory follicles and 3+/-1 pg/mL and 61+/-6 ng/mL in cysts, respectively (P<0.001). Insulin-like growth factor-binding proteins activity was about 10 times higher in cysts than in preovulatory follicles. Cysts were classified into three types according to their estradiol-to-progesterone (E/P) ratio. Type 1 cysts (n=23) exhibited the highest E/P ratio (10.8+/-2.3), partial loss of granulosa cells, and severe morphologic changes in the theca interna. Expression of P(450) side-chain cleavage and P(450) 17 alpha-hydroxylase was noted in theca cells and expression of inhibin-alpha in granulosa cells. Type 2 cysts (n=35) had a low E/P ratio (0.07+/-0.02), and patches of luteal-like tissue in the cystic wall. Type 3 cysts (n=32) had an E/P ratio of 0.91+/-0.17, and no recognizable granulosa or theca cells. In summary, intrafollicular steroid levels as expressed by E/P ratio, together with IGF-I and insulin levels and morphologic changes in the follicular wall, may serve as accurate cyst-classification parameters. Because IGF-I and/or insulin play an essential role in the final stage of follicle development, it can be speculated that abnormal levels of these metabolic hormones might lead to follicle dysfunction, resulting in follicular regression or cyst formation.


Assuntos
Doenças dos Bovinos/patologia , Indústria de Laticínios , Eficiência , Cistos Ovarianos/patologia , Animais , Bovinos , Doenças dos Bovinos/metabolismo , Doenças dos Bovinos/fisiopatologia , Eficiência/fisiologia , Feminino , Líquido Folicular/química , Líquido Folicular/metabolismo , Hormônios Esteroides Gonadais/análise , Hormônios Esteroides Gonadais/metabolismo , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/análise , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/metabolismo , Fator de Crescimento Insulin-Like I/análise , Fator de Crescimento Insulin-Like I/metabolismo , Cistos Ovarianos/metabolismo , Cistos Ovarianos/fisiopatologia , Folículo Ovariano/metabolismo , Folículo Ovariano/patologia
7.
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
8.
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
9.
Cancer Gene Ther ; 15(8): 535-42, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18421310

RESUMO

Ad-PPE-Fas-c is an adenovector that expresses Fas-c under the control of the modified pre-proendothelin-1 (PPE-1) promoter. Fas-c is a chimeric death receptor containing the extracellular portion of tumour necrosis factor 1 receptor (TNFR1) and the transmembrane and intracellular portion of Fas. We recently demonstrated that Ad-PPE-Fas-c induced Fas-receptor-mediated endothelial cell apoptosis. Previously, doxorubicin was shown to enhance Fas-receptor clustering and the induction of its cascade. Therefore, the goal of this work was to test whether doxorubicin augments the capacity of Ad-PPE-Fas-c to induce endothelial cell apoptosis and to elucidate whether either the death-receptor-mediated apoptotic cascade or the mitochondria-associated apoptotic cascade is involved in the combined treatment effect. We found that a combined treatment of Ad-PPE-Fas-c and doxorubicin synergistically induced a reduction in endothelial cell viability and apoptosis. z-IETD-FMK, a caspase-8 inhibitor, and z-LEHD-FMK, a caspase-9 inhibitor, significantly decreased apoptosis induced by the combined treatment. Systemically administered combined therapy significantly reduced the lung metastases burden (70%) in mice as compared to each treatment alone. Thus, a combined treatment of Ad-PPE-Fas-c gene therapy and chemotherapy may be effective in the treatment of metastatic diseases and both the Fas cascade and the mitochondria-associated cascade are essential for this effect.


Assuntos
Apoptose/efeitos dos fármacos , Caspase 8/metabolismo , Caspase 9/metabolismo , Doxorrubicina/administração & dosagem , Endotélio Vascular/efeitos dos fármacos , Terapia Genética , Metástase Neoplásica/prevenção & controle , Neovascularização Patológica/prevenção & controle , Adenoviridae/genética , Animais , Bovinos , Células Cultivadas , Endotélio Vascular/citologia , Vetores Genéticos , Camundongos , Camundongos Endogâmicos C57BL
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.
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
12.
Reproduction ; 129(4): 453-61, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15798020

RESUMO

The onset of gene expression for three proteins that play pivotal roles in theca interna function, namely the LH receptor (LH-R), cytochrome P450 17 alpha-hydroxylase (17 alpha OH) and the steroidogenic acute regulatory protein (StAR), was determined. Ovaries were obtained on day 9 of the oestrus cycle from mature synchronized dairy cows (n = 5) and gene expression in preantral and antral follicles up to 4 mm in diameter was evaluated by in situ hybridization. LH-R and 17 alpha OH mRNAs were observed first, in the theca interna of large preantral follicles (type 4), concurrent with its morphological differentiation. StAR mRNA appeared later during follicular growth, in follicles >1 mm in diameter (type 6). LH-R and 17 alpha OH mRNAs were found exclusively in the thecal cells, whereas StAR mRNA appeared in thecal cells, granulosa cells of late atretic follicles and oocytes. In early atresia, thecal cells expressed all three mRNAs, and their expression decreased gradually as atresia progressed. Atresia in granulosa cells was characterized by massive apoptosis of periantral, but not peribasal cells, that differentiated into luteal-like cells expressing StAR. In summary, our study suggests that in spite of the presence of 17 alpha OH, a key enzyme in steroidogenesis, the ability to produce steroids by bovine follicles smaller than 1 mm in diameter must be very limited due to the absence of StAR protein. During the early stages of atresia, thecal cells remain morphologically and functionally healthy, and continue to express all three studied mRNAs.


Assuntos
Bovinos/metabolismo , Fosfoproteínas/genética , Receptores do LH/genética , Esteroide 17-alfa-Hidroxilase/genética , Células Tecais/metabolismo , Animais , Feminino , Atresia Folicular , Células da Granulosa/metabolismo , Processamento de Imagem Assistida por Computador , Hibridização In Situ/métodos , Oócitos/metabolismo , RNA Mensageiro/análise
13.
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
14.
BJU Int ; 93(4): 474-7, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15008712

RESUMO

ACS is prevalent in various surgical conditions and in a large percentage of critically ill patients. Measuring the IAP is important in the early diagnosis of ACS and can be easily done by measuring the intravesical pressure. ACS adversely affects many organ systems; the pathogenesis of renal dysfunction is probably multifactorial, from a combination of reduced cardiac output, reduced GFR mediated by secretion of renin and angiotensin, aldosterone-mediated water reabsorption, increased renal parenchymal pressure and direct compression of the renal vein. Successful treatment requires a high index of suspicion, prompt recognition and early surgical abdominal decompression.


Assuntos
Abdome/inervação , Síndromes Compartimentais , Doenças Urológicas/complicações , Síndromes Compartimentais/etiologia , Síndromes Compartimentais/fisiopatologia , Síndromes Compartimentais/terapia , Humanos , Pressão
15.
Br Poult Sci ; 45(6): 815-22, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15697022

RESUMO

1. The effect of age on ovarian function was studied in 245-, 350-, 500-, 700- and 800-d-old Lohmann hens. The effect of three different methods for moult induction on ovarian function and corticosterone concentration was studied in 500-d-old hens. 2. No significant reductions in ovarian weight or in number of follicles before the age of 700 d were found. The ability to produce progesterone and oestradiol-17beta was unchanged up to the age of 700 d and the circadian secretion of these two steroids was identical in young (225 d) and old hens (600 d). 3. The effects of induced moulting by feed withdrawal (FW) and a high Zn (HZn) diet on body weight and ovarian function were very similar; those of a moderate Zn with low Ca (MZn/LCa) diet were smaller. 4. The first significant effect of moulting was a decrease in oestradiol-17beta plasma concentration (d 2). Plasma progesterone decreased more gradually than oestradiol-17beta, and reached a nadir on d 6 in FW- and HZn-treated hens and on d 9 in MZn/LCa-treated ones. 5. Hens treated with either FW or the MZn/LCa, but not those with the HZn diet, showed a very sharp rise in corticosterone concentration on d 2 of treatment. Thus the MZn/LCa diet was less efficient than the other treatments in induction of ovarian involution, but had a similar effect on stress induction, as indicated by increases in plasma corticosterone.


Assuntos
Envelhecimento/fisiologia , Galinhas/fisiologia , Muda/fisiologia , Reprodução/fisiologia , Envelhecimento/sangue , Animais , Peso Corporal , Galinhas/sangue , Corticosterona/sangue , Estradiol/sangue , Plumas , Feminino , Privação de Alimentos/fisiologia , Tamanho do Órgão , Ovário/fisiologia , Progesterona/sangue
16.
J Dairy Sci ; 86(6): 2012-21, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12836937

RESUMO

Two experiments examined effects of GnRH administered within 3 h after onset of estrus (OE) on ovulation and conception in dairy cows. In experiment 1, 46 cows received either saline, 250 microg of GnRH, or 10 microg of the GnRH analogue, Buserelin. Cows were observed for estrus, blood samples were collected, and ovulations were monitored by ultrasound. In controls, 76% of cows had intervals from estrus to ovulation of < or = 30 h and 24% had intervals > 30 h. Treatment with either GnRH or GnRH analogue (data combined) increased magnitude of LH surges and decreased intervals from estrus to LH surge or to ovulation. Treated cows all ovulated < or = 30 h after OE. Among control cows, plasma estradiol concentrations before estrus correlated positively with amplitudes of LH surges. Higher plasma progesterone was observed in the subsequent estrous cycle in GnRH-treated cows compared to control cows with delayed ovulations. Experiment 2 included 152 primiparous and 211 multiparous cows in summer and winter. Injection of GnRH analogue at OE increased conception rates (CR) from 41.3 to 55.5% across seasons. In summer, GnRH treatment increased CR from 35.1 to 51.6%. Across seasons, GnRH increased CR from 36.0 to 61.5% in cows with lower body condition at insemination and GnRH increased CR (63.2 vs. 42.2%) in primiparous cows compared to controls. Use of GnRH eliminated differences in CR for cows inseminated early or late relative to OE and increased CR in cows having postpartum reproductive disorders. In conclusion, GnRH at onset of estrus increased LH surges, prevented delayed ovulation, and may increase subsequent progesterone concentrations. Treatments with GnRH increased conception in primiparous cows, during summer, and in cows with lower body condition.


Assuntos
Bovinos/fisiologia , Estro , Fertilização , Hormônio Liberador de Gonadotropina/administração & dosagem , Hormônios/sangue , Ovulação , Animais , Composição Corporal , Estradiol/sangue , Feminino , Hormônio Luteinizante/sangue , Paridade , Gravidez , Progesterona/sangue , Reprodução , Estações do Ano , Fatores de Tempo
17.
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
18.
Clin Exp Immunol ; 127(2): 226-33, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11876744

RESUMO

Lidocaine and related local anaesthetics have been shown to be effective in the treatment of ulcerative colitis (UC). However, the mechanisms underlying their therapeutic effect are poorly defined. Intestinal epithelial cells play an important role in the mucosal inflammatory response that leads to tissue damage in UC via the secretion of pro-inflammatory cytokines and chemokines. The aim of this study was to evaluate the direct immunoregulatory effect of lidocaine on pro-inflammatory cytokine and chemokine secretion from intestinal epithelial cells. HT-29 and Caco-2 cell lines were used as a model system and treated with lidocaine and related drugs. The expression of IL-8, IL-1beta and the IL-1 receptor antagonist (RA) were assessed by ELISA and quantification of mRNA. In further experiments, the effect of lidocaine on the secretion of IL-8 from freshly isolated epithelial cells stimulated with TNFalpha was tested. Lidocaine, in therapeutic concentrations, inhibited the spontaneous and TNFalpha-stimulated secretion of IL-8 and IL-1beta from HT-29 and Caco-2 cell lines in a dose-dependent manner. Similarly, suppression of IL-8 secretion was noted in the freshly isolated epithelial cells. Other local anaesthetics, bupivacaine and amethocaine, had comparable effects. Lidocaine stimulated the secretion of the anti-inflammatory molecule IL-1 RA. Both the inhibitory and the stimulatory effects of lidocaine involved regulation of transcription. The results imply that the therapeutic effect of lidocaine may be mediated, at least in part, by its direct effects on epithelial cells to inhibit the secretion of proinflammatory molecules on one hand while triggering the secretion of anti-inflammatory mediators on the other.


Assuntos
Anestésicos Locais/farmacologia , Interleucina-1/metabolismo , Interleucina-8/metabolismo , Mucosa Intestinal/efeitos dos fármacos , Lidocaína/farmacologia , Sialoglicoproteínas/metabolismo , Adenocarcinoma/patologia , Anestésicos Locais/uso terapêutico , Bupivacaína/farmacologia , Colite Ulcerativa/tratamento farmacológico , Neoplasias do Colo/patologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Humanos , Proteína Antagonista do Receptor de Interleucina 1 , Interleucina-8/biossíntese , Interleucina-8/genética , Mucosa Intestinal/metabolismo , Lidocaína/uso terapêutico , RNA Mensageiro/biossíntese , Tetracaína/farmacologia , Células Tumorais Cultivadas/efeitos dos fármacos , Células Tumorais Cultivadas/metabolismo , Fator de Necrose Tumoral alfa/farmacologia
19.
Reproduction ; 122(5): 737-44, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11690534

RESUMO

The fertility of dairy cows decreases during the summer and remains low during the cooler autumn although the animals are no longer under heat stress. The aim of this study was to characterize a delayed effect of summer heat stress on oocyte quality in the autumn and to improve oocyte quality by enhanced removal of follicles damaged during the previous summer. Lactating cows (n = 16) were subjected to heat stress during the summer. In autumn, ovarian follicles (3-7 mm in diameter) were aspirated by an ultrasound-guided procedure during four consecutive oestrous cycles. Follicles were aspirated from control cows on day 4 and from treated cows on days 4, 7, 11 and 15 of each oestrous cycle. All cows received PGF(2alpha) and GnRH injections on days 19 and 21, respectively, and maintained cyclicity, as indicated by plasma progesterone concentrations. On day 4 of each cycle, the oocytes recovered were examined morphologically, matured and activated in vitro, and cultured for 8 days. In cycle 1 (early October) both groups showed low percentages of grade 1 oocytes, cleavage, four- and eight-cell embryos, morulae and parthenogenetic blastocysts. Subsequently, the number of grade 1 oocytes increased earlier (cycle 2) in treated than in control cows (cycle 3; P < 0.05). The cleavage rate in the control group remained relatively low throughout (32-58%), whereas in the treated group it increased from 40% (cycle 1) to 75% (cycles 3 and 4; P < 0.05). The number at each stage of embryo development increased slightly but remained low throughout in the control group, whereas in the treated group significant (P < 0.05) increases of all stages were observed in cycles 3 and 4. The results show a delayed effect of summer heat stress on oocyte quality and embryo development in the autumn. Enhanced removal of the impaired cohort of follicles led to earlier emergence of healthy follicles and high quality oocytes in the autumn.


Assuntos
Temperatura Alta/efeitos adversos , Oócitos/fisiologia , Folículo Ovariano , Estações do Ano , Animais , Bovinos , Células Cultivadas , Fase de Clivagem do Zigoto , Dinoprosta/farmacologia , Desenvolvimento Embrionário e Fetal , Feminino , Hormônio Liberador de Gonadotropina/farmacologia , Sucção
20.
Reproduction ; 121(5): 745-51, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11427162

RESUMO

During the autumn, the conception rate of dairy cattle in warm countries is low although ambient temperatures have decreased and cows are no longer exposed to summer thermal stress, indicating that there may be a delayed effect of heat stress on cattle fertility. Two experiments were conducted to examine possible delayed effects of heat stress on follicular characteristics and steroid production at two distinct stages of follicular growth: medium-sized and preovulatory follicles, 20 and 26 days after heat exposure, respectively. Lactating cows were subjected to heat stress for 12 h a day in an environmental chamber, during days 2-6 of a synchronized oestrous cycle. In Expt 1, ovaries were collected on day 3 of the subsequent cycle, before selection of the dominant follicle, and medium-sized follicles were classified as atretic or healthy. In Expt 2, on day 7 of the subsequent cycle, PGF(2a) was administered and preovulatory follicles were collected 40 h later. In both experiments, follicular fluid was aspirated, granulosa and thecal cells were incubated, and steroid production was determined. In healthy medium-sized follicles (Expt 1), oestradiol production by granulosa cells and androstenedione production by thecal cells were lower (P < 0.05) and the concentration of progesterone in the follicular fluid was higher in cows that had been previously heat-stressed than in control cows (P < 0.05). In preovulatory follicles (Expt 2), the viability of granulosa cells was lower (P < 0.05) and the concentration of androstenedione in the follicular fluid and its production by thecal cells were lower (P < 0.05) in cows that had been previously heat-stressed than in control cows. In both experiments, the oestradiol concentrations in the follicular fluids were not altered by heat stress. These results demonstrate a delayed effect of heat stress on steroid production and follicular characteristics in both medium-sized and preovulatory follicles; this effect could be related to the low fertility of cattle in the autumn.


Assuntos
Bovinos/fisiologia , Temperatura Alta , Folículo Ovariano/metabolismo , Ovulação , Esteroides/biossíntese , Androstenodiona/análise , Androstenodiona/biossíntese , Animais , Sobrevivência Celular , Dinoprosta/administração & dosagem , Estradiol/análise , Estradiol/biossíntese , Estro , Feminino , Fertilidade , Atresia Folicular , Líquido Folicular/química , Células da Granulosa/metabolismo , Lactação , Progesterona/análise , Progesterona/biossíntese , Estações do Ano , Células Tecais/metabolismo , Fatores de Tempo
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