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71.
Femke?DH?Koedijk Birgit?HB?van BenthemEmail author Eliane?MDC?Vrolings Wim?Zuilhof Marianne?AB?van der Sande 《Emerging themes in epidemiology》2014,11(1):12
Background
Men having sex with men (MSM) remain the largest high-risk group involved in on-going transmission of sexually transmitted infections (STI), including HIV, in the Netherlands. As risk behaviour may change with age, it is important to explore potential heterogeneity in risks by age. To improve our understanding of this epidemic, we analysed the prevalence of and risk factors for selected STI in MSM attending STI clinics in the Netherlands by age group.Methods
Analysis of data from the national STI surveillance system for the period 2006–2012. Selected STI were chlamydia, gonorrhoea, infectious syphilis and/or a new HIV infection. Logistic regression was used to identify factors associated with these selected STI and with overall STI positivity. Analyses were done separately for MSM aged younger than 25 years and MSM aged 25 years and older.Results
In young MSM a significant increase in positivity rate was seen over time (p?<?0.01), mainly driven by increasing gonorrhoea diagnoses, while in MSM aged 25 and older a significant decrease was observed (p?<?0.01). In multivariate analyses for young MSM, those who were involved in commercial sex were at higher risk (OR: 1.5, 95% CI: 1.2-1.9). For MSM aged 25 years and older this was not the case. Having a previous negative HIV test was protective among older MSM compared to those not tested for HIV before (OR: 0.8, 95% CI: 0.8-0.8), but not among younger MSM.Conclusions
MSM visiting STI clinics remain a high-risk group for STI infections and transmission, but are not a homogenous group. While in MSM aged older than 25 years, STI positivity rate is decreasing, positivity rate in young MSM increased over time. Therefore specific attention needs to be paid towards targeted counselling and reaching particular MSM sub-groups, taken into account different behavioural profiles.72.
Contraceptive potential of a mifepristone-nomegestrol acetate sequential regimen in women 总被引:1,自引:0,他引:1
Croxatto HB; Salvatierra AM; Fuentealba B; Massai R 《Human reproduction (Oxford, England)》1998,13(12):3297-3302
The effectiveness of a sequential regimen consisting of mifepristone, 10
mg/day for 15 days, followed by nomegestrol acetate (NOMA), 5 mg/day for
the next 13 days, for inhibiting ovulation and maintaining regular bleeding
cycles was assessed in 10 surgically sterilized volunteers who were
followed for one pretreatment and three treated cycles. Hormonal
determinations in blood and urine, ovarian ultrasonography, bleeding
records in all cycles and an endometrial biopsy taken on day 22-25 of the
third treatment cycle were used to monitor the effects of treatment. During
treatment, 24 monophasic (no sustained progesterone rise above 12 nmol/l)
and six biphasic cycles were recorded. Nine follicular ruptures were
detected echographically in these 30 treated cycles, five of which occurred
in monophasic cycles. All follicular ruptures occurred on days 1-7 of NOMA
treatment. Echographic and endocrine features of ovulatory cycles were both
present in only four treated cycles (13.3%). Development of a secretory
endometrium was achieved in all cases, but it was always irregular. Regular
withdrawal bleeding occurred in all subjects and no adverse reactions were
recorded. The ovarian and endometrial effects of this regimen justify
testing its contraceptive effectiveness in phase 2 clinical trials.
相似文献
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75.
Various authors have reported the incidence of the solitary metastatic lesion to range from 25-85% of cases with known cerebral metastasis. In about 20% of these cases, no primary neoplasm is ever identified. The therapeutic alternatives considered depend to a great extent on the histopathology of the tumour. Unfortunately, the difficulty of making a correct diagnosis in this setting is compounded by all of the problems associated with tumour sampling, i.e. the representativeness of the sample, the often miniscule amounts of tissue obtained, mechanical deformation of the sample, etc. This study describes the use of a monoclonal antibody panel in the immunophenotyping of 45 tumours where the differential diagnosis was glioma versus metastatic tumour with no known primary site. The monoclonal antibodies used bound neuroectodermal antigens (UJ13A), cytokeratin (LE61), and epithelial membrane antigens (AUA1), as well as human milk fat globule antigens (HMFG1, HMFG2). The neuroectodermally-derived MAB UJ13A accurately and reproducibly differentiated gliomas and metastatic lesions with one exception. Oat cell carcinomas (n = 5) were positive for both UJ13A and cytokeratin (LE61). There were no cases in which metastatic tumours were positive for UJ13A and negative for cytokeratin. A combination of the LE61 and AUA1 MABs resulted in positive staining in 44/45 (98%) cases. Immunophenotyping made a substantial contribution in 13 cases (29%), and in three cases the MAB panel was responsible for the final diagnosis. The antibody panel described in this study enables primary CNS neoplasms to be accurately distinguished from nonlymphoid metastatic tumours. In addition, a positive diagnosis of carcinoma is made in 98% cases, although identification of the precise organ of origin is not generally possible. 相似文献
76.
Effect of carotid artery ligation and infusion of fluosol FC-43 emulsion on brain surface oxygen tensions 总被引:1,自引:0,他引:1
J R Laycock H B Coakham I A Silver F J Walters 《Stroke; a journal of cerebral circulation》1986,17(6):1242-1246
In eight rabbits, the common carotid artery was ligated and multiple estimations of brain surface oxygen tension performed using a seven barrelled mini-electrode. In five rabbits ligation of the carotid artery resulted in impairment of cortical oxygenation. The remaining three rabbits showed no impairment in the supply of oxygen to the cerebral cortex after carotid occlusion. In the five rabbits who displayed a reduction in oxygen supply after carotid ligation, ventilation with 33% oxygen after the infusion of 15 ml/kg of Fluosol FC-43 produced an improvement in cortical oxygenation in only three of the five rabbits. When these animals were ventilated with 100% oxygen after carotid ligation and Fluosol infusion, oxygen supply in all five was commensurate with or greater than that during control conditions. 相似文献
77.
V. Papanastassiou B. L. Pizer H. B. Coakham J. Bullimore T. Zananiri J. T. Kemshead 《British journal of cancer》1993,67(1):144-151
A pilot study was undertaken to determine the feasibility of infusing 131I labelled monoclonal antibodies (MoAbs) into either the cavity remaining after resection of malignant glioma or into glioma cysts. Of the seven patients recruited into the study, two had cystic lesions and five resection cavities. Six of the seven were treated after relapse from primary therapy. All patients apart from one, were given a single injection of 131I conjugated to a MoAb (ERIC-1) recognising the human neural cell adhesion molecule (NCAM). One patient received a further injection of 131I-MoAb after regrowth of their disease. Pharmacokinetic studies revealed that the MoAb remained predominantly in the tumour cavity with little leakage into the systemic compartment. This resulted in a high calculated dose of radiation being delivered to the tumour cells either lining or within close proximity to the cavity/cyst wall. In such a small study, it is not possible to determine accurately response rates, but individual patient responses were observed. This, along with the low toxicity noted, demonstrates the feasibility of using 131I-MoAbs in this way. With 131I, radiation dose is deposited in tissue to a depth of 1 mm from the source. The possibility of applying isotopes such as 90Yttrium which will irradiate tumour/tissue to a greater depth (6 mm) is discussed in context with the biology of glioma infiltration into normal brain parenchyma. 相似文献
78.
Sergi K. Obukhov Martin J. Gennie Alison L. Tutt John T. Kemshead Hugh B. Coakham Peter C. Beverley 《Journal of neuro-oncology》1992,13(3):203-210
The ability of IL-2 stimulated mononuclear cells to kill the human glioblastoma cell line U251 has been investigated. Highest cytotoxic activity was generated in low cell density cultures incubated for 15 days with 250–1000 U/ml IL-2. Sub-optimal killing was noted, with cells only exposed to IL-2 for three days. Under the latter conditions, bispecific monoclonal antibodies (MoAbs) of either anti-CD3 or anti-CD16 and an anti-NCAM MoAb stimulated LAK cell activity markedly. Anti-CD16 conjugates were found more effective than anti-CD3 and (Fab)2 constructs more efficacious than those made with whole Ig molecules. Maximal stimulation of LAK cell activity was noted with bispecific MoAbs. Little effect was observed with either single or mixtures of monomeric MoAbs. Furthermore, no effect of bispecific MoAbs was observed when target cells lacked expression of NCAM. These results could be of clinical importance as it is not always feasible to screen LAK cells for optimal activity before administration to patients. Whilst bispecific MoAbs have no effect on optimally stimulated LAK cells, they are not inhibitory and can stimulate killing under sub-optimal IL-2 stimulation. 相似文献
79.
P J Darbyshire S P Bourne P M Allan J Berry A Oakhill J T Kemshead H B Coakham 《Cancer》1987,59(4):726-730
A panel of monoclonal antibodies including antibodies against neuroectodermal antigens, (UJ13A, UJ127.11, UJ181.4), leukocytes (2D1), intermediate filament antigens cytokeratin (LE61), Vimentin, Desmin (Labsystems, Helsinki, Finland), myoglobin, and neurofilament (155) antigens were assessed for their use as an adjunct to light microscopy in pediatric pathology, with particular emphasis on the "small round cell" tumors. One hundred thirty-four tumors were studied using immunofluorescence and immunoperoxidase techniques. The differentiation of neuroblastoma from lymphoma proved to have a clear-cut immunologic profile, as did the rhabdomyosarcomas, which showed consistent positivity with neuroectodermal antibody UJ13A and in positive binding with antidesmin. Ewing's sarcoma did not give a clear immunohistologic pattern with these antibodies. This panel was shown to have been a valuable aid to diagnosis in 12% of cases studied. The future use of such a panel for routine diagnostic use is discussed, but it is emphasized that the binding pattern of these tumors is often heterogeneous, and examination in conjunction with conventional histology is essential if the correct conclusions are to be made. 相似文献
80.