Endocrine integration of fetal ovaries grafted under kidney capsule of unilaterally or bilaterally orchidectomized male hamster / Integración endocrina de ovarios fetales trasplantados bajo la cápsula renal de hámster machos uni o bilateralmente castrados

Mammalian ovary development undergoes important changes during the perinatal period, moment when follicles are assembled and start to develop in a process not well known, involving endocrine and paracrine factors. In order to investigate the effect of two different hormonal environments on the early development of the ovary, we used an autologous transplant model in which Syrian hamster fetal ovaries were grafted under the kidney capsule of males hosts previously unilaterally or bilaterally orchidectomized. After 35 days of graft, ovaries and kidney parenchyme of the host male did not present signs of rejection. Ovaries contained primordial, primary follicles, secondary follicles and few tertiary follicles with morphological features similar to ovaries of control females of 35 days of age. Healthy primary and secondary follicles of experimental groups had frequency distribution and size similar to control ovaries but tertiary follicles were scarce in control as well as in grafts where they were mainly atretic. PCNA, marker of proliferation, was immuno detected in granulosa cells of growing follicles and the marker of apoptosis, Caspase 3 active, was evident mainly in secondary follicles. Immunoreactivity for steroidogenic proteins, StAR, 3-bHSD and aromatase detected in the follicular wall cells and the decreased serum levels of FSH without important changes in testosterone in bilateral orchidectomized males that received ovarian graft, and testosterone decreased without changes in FSH levels in unilateral orchidectomized males (UO) with ovarian graft, all together suggest the effect of steroid hormones produced by the ovary. In conclusion, the experimental model of autologous transplant presents evidence of early ovary development under the kidney capsule and its functional integration to the endocrine axis of the host male.

El desarrollo del ovario en mamíferos sufre importantes cambios durante el periodo perinatal, momento en el cual los folículos se ensamblan y comienzan a desarrollarse en un proceso no muy dilucidado que involucra señales endocrinas y paracrinas. Con el objetivo de investigar el efecto de dos ambientes hormonales sobre el desarrollo temprano del ovario de hamster, usamos un modelo de trasplante autólogo en el que ovarios fetales fueron trasplantados bajo la cápsula renal de machos receptores previamente castrados y hemicastrados. Después de 35 días de trasplante, los ovarios y el parénquima renal de los machos receptores no presentaron señales de rechazo. El ovario presentó folículos primordiales, primarios, secundarios y algunos folículos terciarios con características morfológicas similares a los ovarios de hembras controles de 35 días de edad. Folículos primarios y secundarios sanos de ambos grupos experimentales se encontraron en frecuencia y tamaño similar al de ovarios controles, los folículos terciarios fueron escasos tanto en controles como en ovarios trasplantados, siendo en éstos principalmente atrésicos. PCNA, un marcador de proliferación celular, fue detectado por inmunohistoquímica en células granulosas de folículos en crecimiento, mientras que caspasa 3 activa, un marcador de apoptosis, fue evidente en folículos secundarios. Por otra parte, inmunoreactividad para proteínas esteroidogénicas, StAR, 3-bHSD y aromatasa, fue detectada en la pared folicular. Esta observación, junto a la disminución de niveles séricos de FSH, sin cambios importantes en los niveles de testosterona en machos castrados que recibieron trasplantes ováricos, y la disminución en los niveles de testosterona sin cambios en los niveles de FSH en machos hemicastrados con trasplantes ováricos, sugiere que el ovario no solo produce hormonas esteroidales sino que además éstas modifican los niveles hormonales del macho receptor del trasplante. En conclusión, este modelo de trasplante autólogo agrega información del desarrollo ovárico temprano cuando éste se desarrolla bajo la cápsula renal de machos entregando evidencia de la integración funcional del ovario trasplantado al eje endocrino de los machos receptores.

Human papillomavirus infection and its association with cervical dysplasia in Ecuadorian women attending a private cancer screening clinic

Women living in Latin American countries bear a disproportionate burden of cervical cancer, a condition caused by infection with the human papillomavirus (HPV). We performed a study in Santa Elena, Guayas (currently Santa Elena Province), Ecuador, to determine how often HPV could be detected in women attending a private cancer screening clinic. Participants underwent a Pap test, and vaginal and cervical swabs were performed for HPV testing by the polymerase chain reaction (PCR). Each participant completed a verbally administered survey. The mean age of 302 participants was 37.7 years (range 18 to 78 years). The majorityof cervical and vaginal specimens contained sufficient DNA to perform PCR. Overall, 24.2% of the participants had either a cervical or vaginal swab that tested positive for HPV. In general, there was a good correlation between the HPV types detected in the cervical and vaginal swabs from the participants, but vaginal swabs were more likely to contain HPV DNA than were cervical swabs. The high-risk HPV types 16, 52, 58, and 59 and the low-risk HPV types 62, 71, 72, and 83 were the most frequently detected HPV types. The number of lifetime sexual partners was positively associated with detection of any HPV type, detection of oncogenic HPV, and abnormal Pap smears. Further studies are needed to determine if these results are representative of all Ecuadorian women and to determine if cervical cancers in Ecuadorian women are caused by the same HPV types found in the swab specimens obtained in this study.

Noroviruses associated with acute gastroenteritis in a children's day care facility in Rio de Janeiro, Brazil

Noroviruses (Norwalk-like viruses) are an important cause of gastroenteritis worldwide. They are the most common cause of outbreaks of gastroenteritis in the adult population and occur in nursing homes for the elderly, geriatric wards, medical wards, and in hotel and restaurant settings. Food-borne outbreaks have also occurred following consumption of contaminated oysters. This study describes the application of a reverse transcription-polymerase chain reaction (RT-PCR) assay using random primers (PdN6) and specific Ni and E3 primers, directed at a small region of the RNA-dependent RNA polymerase-coding region of the norovirus genome, and DNA sequencing for the detection and preliminary characterisation of noroviruses in outbreaks of gastroenteritis in children in Brazil. The outbreak samples were collected from children <5 years of age at the Bertha Lutz children's day care facility at Oswaldo Cruz Foundation (Fiocruz), Rio de Janeiro, that occurred between 1996 and 1998, where no pathogen had been identified. At the Bertha Lutz day care center facility, only Fiocruz's employee children are provided for, and they come from different social, economic and cultural backgrounds. Three distinct genogroup II strains were detected in three outbreaks in 1997/98 and were most closely related to genotypes GII-3 (Mexico virus) and GII-4 (Grimsby virus), both of which have been detected in paediatric and adult outbreaks of gastroenteritis worldwide.

GPI-anchored proteins and detergent-resistant membrane domains

Glycosylphosphatidylinositol (GPI)-anchored proteins are expressed on the apical surface of polarized epithelial cells. The anchor may act as an apical sorting signal by associating with clusters or rafts of apically directed glycosphingolipids (GLS). We have previously shown that endogenous GPI-anchored proteins and stably transfected placental alkaline phosphatase (PLAP) can be isolated from detergent lysates of cultured epithelial cells in association with a detergent-insoluble membrane that is rich in GSL. Here, we investigate the behavior of a hybrid GPI-anchored protein, GThy, that contains the ectodomain of the vesicular stomatitis virus glycoprotein (VSV-G) and a GPI-anchor from the Thy1 protein. We have previously shown that GThy is efficiently (85-90 percent) targeted to the apical surface of MDCK cells. Here we show that the protein also becomes insoluble in Triton X-100 as it moves through the secretory pathway of these cells. However, the degree of Triton X-100 insolubility is never as great as that seen for PLAP. This may result from the fact that it is an engineered protein, as the same behavior has been reported for another hybrid GPI-anchored protein. In addition, GThy is rapidly lost from MDCK cells by release into the media, with a t1/2 of about 50 min. This turnorver appears to be mediated by a cell-surface protease that may recognize viral glycoproteins