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141.
Sina V. Jostes Martin Fellermeyer Lena Arévalo Gina E. Merges Glen Kristiansen Daniel Nettersheim Hubert Schorle 《International journal of cancer. Journal international du cancer》2020,146(6):1592-1605
Embryonal carcinomas (ECs) and seminomas are testicular germ cell tumors. ECs display expression of SOX2, while seminomas display expression of SOX17. In somatic differentiation, SOX17 drives endodermal cell fate. However, seminomas lack expression of endoderm markers, but show features of pluripotency. Here, we use chromatin immunoprecipitation sequencing to report and compare the binding pattern of SOX17 in seminoma-like TCam-2 cells to SOX17 in somatic cells and SOX2 in EC-like 2102EP cells. In seminoma-like cells, SOX17 was detected at canonical (SOX2/OCT4), compressed (SOX17/OCT4) and noncomposite SOX motifs. SOX17 regulates TFAP2C, PRDM1 and PRDM14, thereby maintaining latent pluripotency and suppressing somatic differentiation. In contrast, in somatic cells canonical motifs are rarely bound by SOX17. In sum, only 12% of SOX17-binding sites overlap in seminoma-like and somatic cells. This illustrates that binding site choice is highly dynamic and cell type specific. Deletion of SOX17 in seminoma-like cells resulted in loss of pluripotency, marked by a reduction of OCT4 protein level and loss of alkaline phosphatase activity. Furthermore, we found that in EC-like cells SOX2 regulates pluripotency-associated genes, most likely by partnering with OCT4. In conclusion, SOX17 (in seminomas) functionally replaces SOX2 (in ECs) to maintain expression of the pluripotency cluster. 相似文献
142.
The European bee-eater Merops apiaster builds a nest in soil banks comprising a horizontal corridor (159 cm) leading to a 3.4 L nest chamber. An adult and six eggs and/or nestlings occupy this nest for 60 d. Incubation and development are asynchronous. In order to evaluate the gas exchange pattern of the occupied nest, we measured the O2 diffusive conductance of the nest with the ambient environment (GNO2), its internal O2 and CO2 pressures (PNO2 and PNCO2), temperature (TN) and observed the sequences of development and the frequency of parental visits. We also measured the rate of O2 uptake (MO2) of the eggs, nestlings and adults. The GNO2 was 10.9 ml[STPD]/(h.Torr). The PNO2 dropped and the PNCO2 increased during incubation and growth to a maximal change of 24 and 23 Torr, respectively. Maximal MO2 of an egg and a nestling were 5.4 and 146 ml[STPD]/h, respectively. The MO2 of an adult at rest and at TN (27 degrees C) was 90.5 ml[STPD]/h. From clutch size, sequence of nest events, and the above values we have estimated a maximal nest chamber ventilation (VN) of 0.8 L/min necessary to prevent lowering PNO2 to 74 Torr below ambient PO2. This convection is achieved chiefly by the parental feeding visits (up to 40/h). Thus, movement along the corridor convects 1.2 L per visit. 相似文献
143.
Albendazole Therapy in the Treatment of Hydatid Liver Disease 总被引:3,自引:0,他引:3
Hydatid disease, a common health problem in Turkey as in many countries, should be included in the differential diagnosis
of all patients presenting with a cystic mass in the abdominal or thoracic cavity. Previously, surgery had been the main form
of treatment. But with the introduction of preoperative medication with albendazole, treating this disease medically is now
growing in popularity. We report herein the findings of ten patients with two lung and 20 liver hydatid cysts ranging from
3 to 20 cm in diameter, who were successfully treated with medical therapy. Multiple organ involvement and multiple cysts
in an organ are the main indications for medical treatment with albendazole, but the indications should not be limited to
certain situations such as small-sized cysts, since even huge-sized cysts responded well to the therapy in this series.
Received: August 7, 2000 / Accepted: January 9, 2001 相似文献
144.
145.
Uckuyu A Ozcimen EE Sevinc FC Zeyneloglu HB 《Journal of minimally invasive gynecology》2008,15(4):472-475
We wanted to investigate the effect of misoprostol administered vaginally before operative hysteroscopy on cervical dilation, complications, and failure rates in patients who have undergone cesarean section and who have never delivered vaginally. Sixty patients who had undergone cesarean section, who had never delivered vaginally before, and were about to undergo hysteroscopy for various intrauterine lesions were included in this randomized controlled study. Thirty-two patients in the study group were given misoprostol 400 microg, and 28 patients in the control group were given placebo (hexetidine pill) vaginally twice, 6 and 12 hours before the procedure. Primary endpoints were cervical width detected with Hegar dilators and complication and failure rates. Mean cervical width was greater in patients in the study group (6.5 +/- 0.8) than it was in patients in the control group (3.0 +/- 0.6), (p = .0001). Complication and failure rates were lower in patients in the study group (p = .01). Administration of vaginal misoprostol before hysteroscopy proved to be effective in cervical ripening and in reducing complication and failure rates. 相似文献
146.
Arístides A. Pochettino María Belén Hapon Silvana M. Biolatto María José Madariaga Graciela A. Jahn Cintia N. Konjuh 《Drug and chemical toxicology》2016,39(4):392-399
The herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) is used on a wide variety of terrestrial and aquatic broadleaf weeds. 2,4-D has been shown to produce a wide range of adverse effects on animal and human health. The aim of the current study was to evaluate the effects of pre- and postnatal exposure to 2,4-D on rat ventral prostate (VP). Pregnant rats were exposed daily to oral doses of 70?mg/kg/day of 2,4-D from 16 days of gestation up to 23 days after delivery. Then, the treated groups (n?=?8) were fed with a 2,4-D added diet until sacrificed by decapitation on postnatal day (PND) 45, 60, or 90. Morphometric studies were performed and androgen receptor (AR) protein levels in the VP were determined. AR, insulin-like growth factor-I (IGF-1) and insulin-like growth factor-I receptor (IGF-1R) mRNA expression in the VP along with testosterone (T), dihydroxytestosterone (DHT), growth hormone (GH) and IGF-1 serum levels were also determined to ascertain whether these parameters were differentially affected. Results of this study showed that 2,4-D exposure during gestation and until adulthood altered development of the prostate gland in male rats, delaying it at early ages while increasing its size in adults, indicate that 2,4-D could behave as endocrine disruptors (EDs). 相似文献
147.
M. Bulló R. Casas M.P. Portillo J. Basora R. Estruch A. García-Arellano A. Lasa M. Juanola-Falgarona F. Arós J. Salas-Salvadó 《Nutrition, metabolism, and cardiovascular diseases : NMCD》2013,23(5):443-450
Background and AimsEpidemiological and clinical studies suggest that low-glycemic index diets could protect against weight gain. However, the relationship between these diets and adipokines or inflammatory markers is unclear. In the present study we examine how the dietary glycemic index (GI) and dietary glycemic load (GL) are associated with several adipokines and related metabolic risk markers of obesity and diabetes in a cross-sectional and longitudinal manner.Methods and Results511 elderly community-dwelling men and women at high cardiovascular risk were recruited for the PREDIMED trial. Dietary data were collected at baseline and after 1 year of follow-up. The GI and GL were calculated. Plasma leptin, adiponectin and other metabolic risk markers were measured at baseline and after 1 year. At baseline, subjects in the highest quartiles of GI showed significantly higher levels of TNF and IL-6 than those in the lowest quartiles. Dietary GI index was negatively related to plasma leptin and adiponectin levels. After 1 year of follow-up, subjects with a higher increase in dietary GI or GL showed a greater reduction in leptin and adiponectin plasma levels. There was no association between GI or GL and the other metabolic markers measured.ConclusionOur results suggest that the consumption of high-GI or high-GL diets may modulate plasma concentrations of leptin and adiponectin, both adipostatic molecules implicated in energy balance and cardiometabolic risk. 相似文献
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150.
Norberto Arístides Mezzadri Alexandra Catalina Mandry Diego Luis Sinagra Jorge Eduardo Falco Juan Manuel Fernández Vila 《Cirugía espa?ola》2010,87(5):306-311
BackgroundMalignant primary or secondary adrenal tumours are uncommon. For most of them early surgery with adrenalectomy is the only means of cure. Although controversy exists on this issue, the increasing experience in laparoscopic surgery extends the indication for laparoscopic adrenalectomy to potentially malignant and to metastatic adrenal tumours. Our aim was to evaluate the technical feasibility of laparoscopic adrenalectomy for malignant neoplasias, describing the results of our consecutive series of patients.Material and methodsWe retrospectively analysed 13 patients who underwent laparoscopic adrenalectomy for malignant neoplasia between March 1999 and June 2009, at the Hospital de Clínicas of the Universidad of Buenos Aires and at the Hospital Alemán of Buenos Aires. A transperitoneal laparoscopic approach was used in all patients. The mean follow up was 37.9 months (2–84).ResultsThirteen laparoscopic adrenalectomies were performed due to malignant neoplasia. Mean age was 55.2+12 years. The relationship between male and female was 10/3. Five patients had an adrenal carcinoma, 1 patient a malignant phaeochromocytoma, and 7 patients had metastatic tumours. Three patients required conversion to laparotomy. Average operation time was 146.4 min. There were two perioperative complications and no mortality. Average length of hospital stay was 4.6 days (1–35). The survival at 3 years was 46%. The cause of death was the underlying disease in all cases.ConclusionLaparoscopic adrenalectomy is a reasonable technique for malignant adrenal tumours, when the open oncological resection can be reproduced by the laparoscopic approach. 相似文献