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71.

Objective

To analyse for the first time the response of the corticotroph-type and the melanotroph-type pituitary proopiomelanocortin (POMC) system with regard to in-vitro fertilisation (IVF) treatment using self-developed highly specific non-cross-reacting radioimmunoassay.

Study design

Setting: University hospital. Patients: A total of 28 patients undergoing IVF oocyte retrieval. Cross sectional exploratory study, one factorial design with repeated measurements on one factor, non-parametric tests. Blood was collected before anaesthesia (tA) (n = 28) and immediately after oocyte retrieval (tB) (n = 28). Main outcome measure(s): β-endorphin immunoreactive material (IRM), acetyl-N-β-endorphin IRM, β-lipotropin IRM, ACTH, cortisol, estradiol, progesterone, prolactin, luteinizing hormone, and follicle-stimulating hormone. For determination of authentic β-endorphin [β-endorphin (1–31)] a highly specific two-site fluid phase immunoprecipitation radioimmunoassay was developed, which did not cross-react with any β-endorphin derivative or any other opioid peptide tested.

Results

No response of acetyl-N-β-endorphin IRM and of authentic β-endorphin (1–31) was observed to oocyte retrieval in contrast to a significant increase of corticotroph-type proopiomelanocortin derivatives. A significant rise in prolactin plasma concentration indicates a pronounced lactotroph response to oocyte retrieval stress. No significant correlation between POMC derivates and prolactin and between POMC derivatives and gonadotropins or sexual steroids except for ACTH and progesterone and for β-endorphin IRM and estradiol was observed.

Conclusion

IVF treatment stress led to significant corticotroph-type POMC and lactotroph responses, but not to responses of authentic β-endorphin or melanotroph-type POMC in women undergoing oocyte retrieval.  相似文献   
72.
OBJECTIVES: Ovarian cancers still remain a significant worldwide epidemiological problem. The vast majority of newly diagnosed cases are in advanced clinical stages, and the five-year survival rate in all clinical stages amounts up to less than fifty percent. A better understanding of the biology of ovarian cancer can bring us closer to successful treatment and recovery. The aim of this study was to evaluate the expression of luteinizing hormone (LH)/human chorionic gonadotropin (hCG) receptor (LH/hCGR) and the expression of hCG protein in the ovarian cancer tissue. MATERIALS: Histologically proven primary ovarian cancer samples (n=20) were obtained from women undergoing gynecologic surgery. Frozen sections of ovarian cancer tissues were evaluated by means of indirect immunofluorescence. RESULTS: The expression of hCG protein was ubiquitous throughout all samples, while LH/hCGR was detected in only sixty percent of samples. Co-expression of LH/hCGR and hCG protein was detected in some individual cells in tumor tissue. Some cancer cells expressed only hCG protein, but not LH/hCGR. CONCLUSIONS: Expression of LH/hCG receptor is a characteristic feature of various histological types of ovarian cancer. Co-expression of LH/hCGR and hCG protein in individual cancer cells may point to an autocrine or paracrine mechanism of _hCG activity in the tumor microenvironment. Further studies are needed to evaluate LH/hCGR and hCG protein function in the course of neoplastic development.  相似文献   
73.
Pregnancy offers a unique opportunity for the early diagnosis of cervical cancer, due to the fact that pregnant patients have many possibilities of gynecological and cytological examinations. There is much evidence that pregnant women have two to three-fold higher chance of having preneoplastic lesions and early, operable stages of disease diagnosed. The preneoplastic lesions do not require any intervention during pregnancy. However, precise, serial colposcopic examinations, completed by biopsy if necessary, must be seriously considered in order to exclude invasive cancer. The only indication for conization during pregnancy is to rule out or confirm microinvasive or invasive cancer, provided such diagnose can change the time and the way of delivery. Invasive cervical cancer diagnose is frequently associated with difficult medical and ethical decisions. The most proper approach should be considered, taking into account the benefit of the mother and the child. The decision is easier in the early stage of cancer, because it has been proven that six- to twelve-week delay of the beginning of the therapy does not deteriorate the cancer outcome but it enables the fetus to acquire sufficient lung maturity. Advanced carcinoma of the cervix forces us to take prompt therapeutic decisions. Both, the continuation of the pregnancy and the administration of neoadjuvant chemotherapy are still possible.  相似文献   
74.
Mediastinal emphysema and subcutaneous emphysema are rare complications of labor. We have described a case of mediastinal and subcutaneous emphysema, observed in the II stage of labor in otherwise healthy primigravida. The diagnosis was confirmed clinically and by X-ray, and endoscopies examination in District Hospital and in Clinical Department of Surgery. The etiology of this condition was not established. The mediastinal and subcutaneous emphysema, disappeared spontaneously which was confirmed by check-up after 3 months.  相似文献   
75.
OBJECTIVE: Well-known natural unspecific antimicrobial factors acting in the vagina are additionally reinforced during menstrual bleeding by hemocidins--a recently discovered novel class of microbicidal peptides generated proteolytically from hemoglobin. The aim of the presented research was to investigate the relation between the average length of menstrual bleeding and the frequency of urogenital infections. We expected that the shorter menstrual bleeding might increase the risk of urogenital infections because is synonymous with the shorter period of exposition on bactericidal action of hemocidins. STUDY DESIGN: The study contains statistical analysis of an average declared length of menstrual bleeding in the group of 267 young, sexually active women with the symptoms of urogenital infections. The control group consisted of 300 young healthy women. RESULTS: The length of menstrual bleeding in the group of patients with urogenital infections (average 4.35 days) was statistically significantly shorter than in the control group (average 4.95 days). The average length of the menstrual cycle was equal and counted ca. 28 days in both groups. CONCLUSION: The length of menstrual bleeding seems to be a significant factor in the vaginal ecology maintenance.  相似文献   
76.
The process of foaming poly(caprolactone)-based composite materials using supercritical carbon dioxide was analyzed, especially in terms of the biocompatibility of the resultant materials. The influence of foaming process conditions and composite material properties on the functional properties of polymer solid foams, intended for artificial scaffolds for bone cell culture, was investigated. The relationship between wettability (contact angle) and water absorption rate as a result of the application of variable conditions for the production of porous structures was presented. For the evaluation of potential cytotoxicity, the MTT and PrestoBlue tests were carried out, and animal cells (mouse fibroblasts) were cultured on the materials for nine days. There was no toxic effect of composite materials made of poly(caprolactone) containing porogen particles: hydroxyapatite, crystalline nanocellulose, and graphene oxide on cells. The desired effect of the porogens used in the foaming process on the affinity of cells to the resultant material was demonstrated. The tested materials have been shown to be biocompatible and suitable for applications in biomedical engineering.  相似文献   
77.
Glulam beams are increasingly used in the construction industry because of their high strength and the possibility of using round timber with smaller cross-sections. The load-bearing capacity of beams is strongly related to the quality of the outer layers and, in the case of wood, especially the tension zones. For these reasons, this study decided to replace the outer lamella with tensile plywood. The produced beams were subjected to static bending strength and modulus of elasticity evaluation. It was shown that the best static bending strength values were obtained for beams containing plywood in the tension layer. However, the change in structure in the tension zone of beams made of glued laminated timber results not only in an increase in the load capacity of elements produced in this way but also in a decrease in the range/range of the obtained results of bending strength. This way of modifying the construction of glued laminated beams allows a more rational use of available pine timber.  相似文献   
78.
BackgroundPlatelets play a vital role in the neoplastic process. Platelet parameters are hence an important source of information concerning ongoing neoplastic disease. The aim of the study is to assess the impact of selected platelet parameters on the survival of patients with non-small cell lung cancer (NSCLC).MethodsThe study included 532 (174 female and 358 male) patients aged 36–84 years (mean age 63.6 years) operated on due to NSCLC, staged IA–IIIA. Before the operation, all patients received a blood morphology test. The following parameters were subjected to statistical analysis: platelet count, mean platelet volume (MPV) parameter, platelet distribution width (PDW) parameter, platelet-to-lymphocyte ratio (PLR) and systemic immune-inflammation (SII) index. These findings were compared with the clinical data of the patients, and the probability of overall survival was analyzed.ResultsThe univariate analysis revealed a correspondence between PDW, MPV, PLR and SII index and patient survival. The multivariate analysis including patient clinical data found the following factors to have negative prognostic value for patients operated on due to NSCLC: male sex, advancement stage of neoplastic disease and Charlson Comorbidity Index (CCI) above 4, and PLR >144.ConclusionsPDW value, PLR and SII index are independent prognostic factors. In the multi-factor model, male sex, the advancement stage of the neoplastic disease, CCI above 4 and PLR lower than 144 had the greatest prognostic value.  相似文献   
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