951 resultados para Ovarian follicle superovulation


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Leptodactylus(Lithodytes) lineatus (Schneider, 1799) is an Amazonian leaf litter frog considered rare or uncommon in several studies on anuran communities. Despite being a widely distributed frog in Amazonian forests, knowledge of the biology and ecology of this species is relatively scarce. This species has been reported to live in association with leaf-cutter ant nests (Atta spp.) during the breeding period. In this paper we present data on the seasonality of this species and some reproductive information gathered at a locality of Rondônia state, northwestern Brazil. Field work was carried out between April 2001 and March 2002, with the use of pitfall traps with drift fences as a survey method. Leptodactylus (L.) lineatus had a higher capture frequency in this locality compared to that of other studies carried out in other Amazonian localities, possibly because this species has secretive habits, such as calling and breeding from nests of leaf-cutting ants, and are difficult to find during visual encounter surveys. The breeding period occurs between October and March. Calling males and egg-bearing females were found between September and February and juvenile recruitment occurred mainly from the end of the rainy season to the beginning of the dry season (February to June). Males and females show sexual dimorphism in SVL, females being significantly larger than males. The number of ovarian eggs per female varies from 110 to 328 and analyses indicate that there is a significant correlation with SVL.

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A chemical test previously described for the diagnosis of pregnancy was applied to the study of the excretion of gonadotropin in the urine during menstrual cycle. The chemical test is based on the selective adsorption by kaolim of the reducing substances biologically related to urinary gonadotropin. The active substance when acidified to pH 4.0 is adsorbed by the kolin and eluated with O.1N sodium hydroxide. The alkaline solution is treated by Somogyi's copper reagent and the excess not reduced is titrated by 0.005 N sodium thiosulfate. Gonadotropin is quantitatively addorbed by kaolin at pH 4.0 and eluated by alkaline solution as previously demonstrated by the A. (1). In the present paper the complete menstrual cycle was studied daily. It was observed that normally there are two distinct maxima of excretion. This study is based on 11 normal cycles (24-30 days) and 34 abnormal ones. Normal cycles showed a intramenstrual estrogens elimination from 200 to 260 mice units determinated by the Allen - Doisy full estrus smear test. The abnormal cycles belonging also to normal women showed much less estrogen excretion (14 to 25 mice units) Table II). In those cases with decreased estrogen excretion no fall in the curve after 14 th. day was observed. The A. suggest that the peaks of gonadotropin excretion is not related to the oculation but possibly due, the first one, to the follicle stimulating hormone and the second to the luteinizing hormone of hormone stimulating of the inerstitial tissue.

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Aberrant blood vessels enable tumor growth, provide a barrier to immune infiltration, and serve as a source of protumorigenic signals. Targeting tumor blood vessels for destruction, or tumor vascular disruption therapy, can therefore provide significant therapeutic benefit. Here, we describe the ability of chimeric antigen receptor (CAR)-bearing T cells to recognize human prostate-specific membrane antigen (hPSMA) on endothelial targets in vitro as well as in vivo. CAR T cells were generated using the anti-PSMA scFv, J591, and the intracellular signaling domains: CD3ζ, CD28, and/or CD137/4-1BB. We found that all anti-hPSMA CAR T cells recognized and eliminated PSMA(+) endothelial targets in vitro, regardless of the signaling domain. T cells bearing the third-generation anti-hPSMA CAR, P28BBζ, were able to recognize and kill primary human endothelial cells isolated from gynecologic cancers. In addition, the P28BBζ CAR T cells mediated regression of hPSMA-expressing vascular neoplasms in mice. Finally, in murine models of ovarian cancers populated by murine vessels expressing hPSMA, the P28BBζ CAR T cells were able to ablate PSMA(+) vessels, cause secondary depletion of tumor cells, and reduce tumor burden. Taken together, these results provide a strong rationale for the use of CAR T cells as agents of tumor vascular disruption, specifically those targeting PSMA. Cancer Immunol Res; 3(1); 68-84. ©2014 AACR.

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Summary : The hypothalamus represents less than 1 % of the total volume of the brain tissue, yet it plays a crucial role in endocrine regulations. Puberty is defined as a process leading to physical, sexual and psychosocial maturation. The hypothalamus is central to this process, via the activation of GnRH neurons. Pulsatile GnRH secretion, minimal during childhood, increases with the onset of puberty. The primary function of GnRH is to regulate the growth, development and function of testes in boys and ovaries in girls, by stimulating the pituitary gland secretion of luteinizing hormone (LH) and follicle-stimulating hormone (FSH). Several factors contribute to the timing of puberty, including sex and ethnicity, genetics, dietary intake and energy expenditure. Kisspeptins constitute a family of small peptides arising from the proteolytic cleavage of metastin, a peptide with 54 amino acids initially purified from human placenta. These kisspeptins were the subject of much attention following their discovery because of their antimetastatic properties, but it was more recently that their determining role in the reproductive function was demonstrated. It was shown that kisspeptins are ligands of a receptor, GPR54, whose natural inactivating mutation in humans, or knockout in the mouse, lead to infertility. GnRH neurons play a pivotal role in the central regulation of fertility. Kisspeptin greatly increases GnRH release and GnRH neuron firing activity, but the neurobiological mechanisms for these actions are unknown. Gprotein-coupled receptor 54, the receptor for kisspeptin, is expressed by GnRH neurons as well as other hypothalamic neurons, suggesting that both direct and indirect effects are possible. In the first part of my thesis, we investigated a possible connection between the acceleration of sexual development induced by leptin and hypothalamic metastin neurons. However, the data generated by our preliminary experiments confirmed that the commercially available antibodies are non-specific. This finding constituted a major drawback for our studies, which relied heavily upon the neuroanatomical study of the hypothalamic metastinergic pathways to elucidate their sensitivity to exogenous leptin. Therefore, we decided to postpone any further in vivo experiment until a better antibody becomes available, and focused on in vitro studies to better understand the mechanisms of action of kisspeptins in the modulation of the activity of GnRH neurons. We used two GnRH-expressing neuronal cell lines to investigate the cellular and molecular mechanisms of action of metastin in GnRH neurons. We demonstrated that kisspeptin induces an early activation of the MAP kinase intracellular signaling pathway in both cell lines, whereas the SAP/JNK or the Akt pathways were unaffected. Moreover, we found an increase in GnRH mRNA levels after 6h of metastin stimulation. Thus, we can conclude that kisspeptin regulates GnRH neurons both at the secretion and the gene expression levels. The MAPK pathway is the major pathway activated by metastin in GnRH expressing neurons. Taken together, these data provide the first mechanism of action of kisspeptin on GnRH neurons. Résumé : L'hypothalamus est une zone située au centre du cerveau, dont il représente moins de 1 du volume total. La puberté est la période de transition entre l'enfance et l'age adulte, qui s'accompagne de transformations somatiques, psychologiques, métaboliques et hormonales conduisant à la possibilité de procréer. La fonction principale de la GnRH est la régulation de la croissance, du développement et de la fonction des testicules chez les hommes, et des ovaires chez les femmes en stimulant la sécrétion de l'hormone lutéinisante (LH) et de l'hormone folliculostimulante (FSH) par la glande hypophysaire. Plusieurs facteurs contribuent au déclanchement de la puberté, y compris le sexe et l'appartenance ethnique, la génétique, l'apport alimentaire et la dépense énergétique. Les Kisspeptines constituent une famille de peptides résultant de la dissociation proteolytique de la métastine, un peptide de 54 acides aminés initialement purifié à partir de placenta humain. Ces kisspeptines ont fait l'objet de beaucoup d'attention à la suite de leur découverte en raison de leurs propriétés anti-metastatiques, et c'est plus récemment que leur rôle déterminant dans la fonction reproductive a été démontré. Les kisspeptines sont des ligands du récepteur GPR54, dont la mutation inactivatrice chez l'homme, ou le knockout chez la souris, conduisent à l'infertilité par hypogonadisme hypogonadotrope. Les neurones à GnRH jouent un rôle central dans le règlement des fonctions reproductrices et la kisspeptine stimule l'activité des neurones à GnRH et la libération de GnRH par ces neurones. Toutefois, les mécanismes neurobiologiques de ces actions ne sont pas connus. Dans la première partie de ma thèse, nous avons étudié le lien potentiel entre l'accélération du développement sexuel induite par la leptine et les neurones hypothalamiques à metastine. Les données générées dans cette première série d'expériences ont malheureusement confirmé que les anticorps anti-metastine disponibles dans le commerce sont aspécifiques. Ceci a constitué un inconvénient majeur pour nos études, qui devaient fortement s'appuyer sur l' étude neuroanatomique des neurones hypothalamiques à metastine pour évaluer leur sensibilité à la leptine exogène. Nous avons donc décidé de focaliser nos travaux sur une étude in vitro des mécanismes d'action de la kisspeptine pour moduler l'activité des neurones à GnRH. Nous avons utilisé deux lignées de cellules neuronales exprimant la GnRH pour étudier les mécanismes d'action cellulaires et moléculaires de la metastine dans des neurones. Nous avons ainsi pu démontrer que la kisspeptine induit une activation précoce de la voie f de signalisation de la MAP kinase dans les deux lignées cellulaires, alors que nous n'avons observé aucune activation de la voie de signalisation de la P13 Kinase et de la SAP/JNK. Nous avons en outre démontré une augmentation de l'expression de la GnRH par la stimulation avec la Kisspeptine. L'ensemble de ces données contribue à élucider le mécanisme d'action avec lequel la kisspeptine agit dans les neurones à GnRH, en démontrant un effet sur l'expression génique de la GnRH. Nous pouvons également conclure que la voie de la MAPK est la voie principale activée par la metastine dans les neurones exprimant la GnRH.

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Eggs of Manduca sexta contain four well-characterized protein derived from hemolymph: vitellogenin and lipophorin (very high density lipoproteins); microvitellogenin, a 26,000 dalton female-specific protein lacking lipid and carbohydrate, and insecticyanin, a blue biliprotein composed of four identical 22,000 dalton subunits. In addition, eggs contain a large store of triacyl glycerols. It has been shown that vitellogenin and lipophorin are actively taken up by follicles in vitro. The lipid components of these two proteins together account for only 10% of egg lipid. The follicle actively sequesters intact high density lipophorin, which, inside the oocyte, is stripped of much of its neutral lipid and two molecules of apolipophorin III. On the other hand, low density lipophorin donates diacylglycerol to the oocyte without its protein components being sequestered. Most of the egg lipid is transported from the fat body by a shuttle system involving low density lipophorin.

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BACKGROUND: Menarche and menopause mark the onset and cessation, respectively, of ovarian activity associated with reproduction, and affect breast cancer risk. Our aim was to assess the strengths of their effects and determine whether they depend on characteristics of the tumours or the affected women. METHODS: Individual data from 117 epidemiological studies, including 118 964 women with invasive breast cancer and 306 091 without the disease, none of whom had used menopausal hormone therapy, were included in the analyses. We calculated adjusted relative risks (RRs) associated with menarche and menopause for breast cancer overall, and by tumour histology and by oestrogen receptor expression. FINDINGS: Breast cancer risk increased by a factor of 1·050 (95% CI 1·044-1·057; p<0·0001) for every year younger at menarche, and independently by a smaller amount (1·029, 1·025-1·032; p<0·0001), for every year older at menopause. Premenopausal women had a greater risk of breast cancer than postmenopausal women of an identical age (RR at age 45-54 years 1·43, 1·33-1·52, p<0·001). All three of these associations were attenuated by increasing adiposity among postmenopausal women, but did not vary materially by women's year of birth, ethnic origin, childbearing history, smoking, alcohol consumption, or hormonal contraceptive use. All three associations were stronger for lobular than for ductal tumours (p<0·006 for each comparison). The effect of menopause in women of an identical age and trends by age at menopause were stronger for oestrogen receptor-positive disease than for oestrogen receptor-negative disease (p<0·01 for both comparisons). INTERPRETATION: The effects of menarche and menopause on breast cancer risk might not be acting merely by lengthening women's total number of reproductive years. Endogenous ovarian hormones are more relevant for oestrogen receptor-positive disease than for oestrogen receptor-negative disease and for lobular than for ductal tumours. FUNDING: Cancer Research UK.

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BACKGROUND: In female adolescents and young adults, malignancies of the genital tract are the most frequent type of cancer, closely followed by Hodgkin's and non-Hodgkin's lymphomas. CASE PRESENTATION: We report an unusual case of sporadic Burkitt's lymphoma (BL) presenting with massive bilateral ovarian infiltration, peritoneal carcinomatosis and diffuse nodular lesions of the stomach and the intestine mimicking Krukenberg tumor. Diagnostic biopsies were obtained by endoscopy of the upper gastrointestinal tract. With intensive chemotherapy, complete remission was rapidly achieved, without life-threatening tumor lysis syndrome. CONCLUSION: Besides metastatic gastric adenocarcinoma, BL is an important differential diagnosis in adolescents presenting with Krukenberg tumor.

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Ovaries up to the 8th day pupae of Dermatobia hominis were studied by transmission electron microscopy. Ovarioles were recognized in ovaries of 4-day old pre-pupae, surrounded by a thin tunica propria of acellular fibrilar material similar in structure to the internal portion of the external tunica of the ovary. There is continuity of the tunica propria and the ovarian tunica, indicating that the former structure originates from the tunica externa. In 5 to 7-day pupae the interstitial somatic cells from the apical region of the ovary, close to the ovarioles, show delicate filamentous material inside of their rough endoplasmic reticulum cisternae; similar material is seem among these cells. Our observations suggest that interstitial somatic cells do not originate the tunica propria but contribute to its final composition.

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In this paper a number of anticancer agents of natural origin will be presented. Hydroxycamtothecin (HCPT) was found to produce a strong inhibitory action on a variety of animal tumors. It is also effective for treatment of patients with gastric carcinoma, liver carcinoma, tumor of head and neck or leukemia. Pharmacologic studies showed that it could depress S phase of tumor cells significantly and cause formation of cellular chromatid breaks. By means of alkaline elution and nick translation methods it has been proved that HCPT induced DNA singlo strand breaks remarkably. Homoharringyonine (hhrt) was shown to be effective against acute leukemia. Recent experiments in tumor-bearing mice inidcated that (HHRT) could diminish tumor metastasis. Using molecular hybridization technique it was demonstrated that (HHRT) decreased the content of c-myc RNA in the cytoplasm but not in the nuclei. Lycobetaine (LBT) poddrddrf dytnh inhibitory effects on a number of ascites tumors. In clinical trials it was against ovarian and gastric carcinomas. It is able to intercalate into DNA. Oxalysine (OXL) is a new antibiotic and shown to be effective against tumor metastatis. When used in combination with 5-FU, its anticancer action could be enhanced. Other natural compounds such as indirubin, ß-elemene, irisquinone, oridonine, norcantharidin and PSP have been also found to possess antitumor action.

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Dermatomyositis (DM) and polymyositis (PM) are idiopathic inflammatory muscle diseases which remain a therapeutic challenge. The association between DM and malignancy is relatively well established while this relationship is weaker with PM. The clinical management and research for an occult malignancy as well as the follow-up of patients with DM or PM is a matter of debate. Herein we report a case of DM who, despite an extensive clinical, radiological and biological work-up developed an occult ovarian cancer 12 months after the initial diagnosis. This case report was used as support to review the actual expert recommendations for the search of an occult malignancy in presence of DM or PM.

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We show here that the alpha, beta, and gamma isotypes of peroxisome proliferator-activated receptor (PPAR) are expressed in the mouse epidermis during fetal development and that they disappear progressively from the interfollicular epithelium after birth. Interestingly, PPARalpha and beta expression is reactivated in the adult epidermis after various stimuli, resulting in keratinocyte proliferation and differentiation such as tetradecanoylphorbol acetate topical application, hair plucking, or skin wound healing. Using PPARalpha, beta, and gamma mutant mice, we demonstrate that PPARalpha and beta are important for the rapid epithelialization of a skin wound and that each of them plays a specific role in this process. PPARalpha is mainly involved in the early inflammation phase of the healing, whereas PPARbeta is implicated in the control of keratinocyte proliferation. In addition and very interestingly, PPARbeta mutant primary keratinocytes show impaired adhesion and migration properties. Thus, the findings presented here reveal unpredicted roles for PPARalpha and beta in adult mouse epidermal repair.

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Gonadotropin hormones undergo important dynamic changes during life. Their rise during puberty stimulates gonadal steroid secretion, triggering the development of secondary sexual characteristics and the acquisition of fertility. The full spectrum of possible mutations and polymorphisms in the human gonadotropins and in their receptor genes has been described in recent years. Patients harboring these mutations display a very wide range of phenotypes affecting all aspects of the reproductive axis. An important insight provided by the careful study of these patients lies in the striking gender differences in the phenotypes associated with a given mutation. As a result, the careful study of these rare patients has allowed us to better define the respective roles of luteinizing hormone and follicle-stimulating hormone in normal human pubertal development and in the achievement of full fertility potential in either males or females. In this work, we describe briefly the known mutations in the genes for both gonadotropins and their receptors, and discuss their genotype/phenotype correlations in light of these important gender differences.

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Cervical lymph nodes biopsies from 31 HIV positive patients (with or without AIDS) were studied by histologic methods and immunohistochemistry (StreptABC staining of paraffin sections) to identify cellular and extracellular matrix components. The results were the following: (1) the biopsies were included in the stages of follicular hyperplasia without fragmentation FH-FF (4 cases); follicular hyperplasia with follicular fragmentation FH+FF (16 cases); follicular involution FI (6 cases) and diffuse pattern DP (5 cases); (2) the most important alteration was the germinal centers disruption due to follicle lysis, which began in the light zone; (3) there was coincidence between intrafollicular hemorrhages and segmental hyaline mycroangiopathy; (4) during the progression of the disease occurred: (a) an increase in the number of mast cells, CD68+ and Mac387+ macrophages; (b) a diffuse augment of collagen III, elastic fibers, laminin, fibronectin and proteoglycans; (c) maintenance of Factor VIII - related antigens in the vascular endothelial cells, with decrease in the expression of Ulex-Europeus I lectin. Follicular hyperplasia (FH-FF or FH+FF) was the most common histologic pattern recognized in the lymph nodes of patients without AIDS and follicular involution and difuse pattern were seen in those who had AIDS. The results indicate that the lymph node biopsies may provide important information about the evolutive stage of the disease and its prognosis.

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Trisomy-21 (Down syndrome) is the most frequent chromosomal abnorm- ality but only one third of cases would be detected by amniocentesis based on maternal age alone. Serum screening tests in the early second trimester increase the detec- tion rate to 60-65%, and more recently it was found that such screening was also possible in the first trimester by quantifying a diffe- rent panel of markers. The concen- trations of these placental proteins are strongly dependent on gestatio- nal age; thus control medians must be established and precise dating is essential. Serum chorionic gonado- trophin (HCG) levels were recently found to be increased in IVF preg- nancies compared to spontaneous gestations, leading to a falsely ele- vated trisomy screening risk. The aim of this preliminary study was to find out whether, in the first-trime- ster screening, the markers similarly differed between IVF and spontane- ous pregnancies which would call for the establishment of separate normal medians for IVF patients. We compared 24 pregnancies ob- tained after ovarian stimulation and IVF with six women after thawed embryo transfer (unstimulated cycle) and 63 gestation- and maternal-age matched spontaneously pregnant controls. A single serum was ob- tained between 6 and 16 weeks of gestation and various placental protein levels determined by im- munometric assays. Serum levels of pregnancy-associated plasma protein A (PAPP-A), which is the major marker in the first-trimes- ter screening test, were reduced in IVF pregnancies: after 9 weeks of gestation, multiples of median (MoMs) ranged between 0.23 and 3.58 (logarithmic mean 0.743). For the frozen/thawed transfers, this value was 1.08. In the 9-12 week group containing 6 cases of IVF, three thawed transfers and 25 con- trols, PAPP-A was significantly redu- ced in the stimulated compared to the nonstimulated cycles. In the late first and early second trimester the difference was not significant in our small group but the trend persisted. Pregnancies after IVF will thus show an increased incidence of false positive results in fetal trisomy-21 screening, and special medians should be established for these pati- ents.

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BACKGROUND & AIMS: The follicle-associated epithelium (FAE) that overlies Peyer's patches (PPs) exhibits distinct features compared with the adjacent villus epithelium. Besides the presence of antigen-sampling membranous M cells and the down-regulation of digestive functions, it constitutively expresses the chemokine CCL20. The mechanisms that induce FAE differentiation and CCL20 expression are poorly understood. The aim of this work was to test whether lymphotoxin beta receptor signaling (LTbetaR), which plays a central role in PPs' organogenesis, mediates CCL20 gene expression in intestinal epithelial cells. METHODS: CCL20, lymphotoxin beta (LTbeta) and LTbetaR expression were monitored during embryonic development by in situ hybridization of mouse intestine. The human intestinal epithelial cell line T84 was used to study CCL20 expression following LTalpha(1)/beta(2) stimulation. In vivo CCL20 expression following agonistic anti-LTbetaR antibody treatment was studied by laser microdissection and quantitative RT-PCR. RESULTS: CCL20 was expressed in the FAE before birth at the time when the first hematopoietic CD4(+)CD3(-) appeared in the PP anlage. LTbetaR was expressed in the epithelium during PP organogenesis, making it a putative target for LTalpha(1)beta(2)signals. In vitro, CCL20 was induced in T84 cells upon LTbetaR signaling, either using an agonistic ligand or anti-LTbeta receptor agonistic antibody. LTalpha(1)beta(2)-induced CCL20 expression was found to be NF-kappaB dependent. LTbetaR signaling up-regulated CCL20 expression in the small intestinal epithelium in vivo. CONCLUSIONS: Our results show that LTbetaR signaling induces CCL20 expression in intestinal epithelial cells, suggesting that this pathway triggers constitutive production of CCL20 in the FAE.