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991.
Birner P Piribauer M Fischer I Gatterbauer B Marosi C Ambros PF Ambros IM Bredel M Oberhuber G Rössler K Budka H Harris AL Hainfellner JA 《Brain pathology (Zurich, Switzerland)》2003,13(2):133-143
No data exist on angiogenic patterns and their prognostic impact in human glioblastoma. Such data are relevant for translation of antiangiogenic therapies into clinical applications. Using immunohistochemistry for CD34, we assessed vascular patterns in 114 primary glioblastomas. Vascular patterns comprised unevenly distributed glomeruloid/garland-like/clustered bizarre vascular formations and evenly distributed delicate capillary-like microvessels ("classic" vascular pattern). The combination of low content of bizarre vascular formations and prominent classic vascular pattern (n=29) was an independent factor for longer survival (p=0.006, Cox regression), as well as postoperative high Karnofsky performance status (p=0.005). In patients with a prominent classic vascular pattern, there was no difference of MIB1 labeling index whereas microvessel density and apoptotic index (TUNEL) were significantly higher as compared to all other patients (p<0.05). In addition, diffuse expression of hypoxia-inducible factor (HIF)-1alpha and strong expression of vascular endothelial growth factor were more common (p<0.05, Chi-square test). FISH revealed loss of chromosomes 1p and 19q only in 1/7 long-time survivors with classic pattern. We conclude that vascular patterns in primary glioblastoma influence clinical outcome and associate with variable expression of angiogenic proteins. Our findings denote for the first time distinct angiogenic subtypes of human glioblastoma which may prove relevant for anti-angiogenic therapy approaches. 相似文献
992.
Virus subversion of the MHC class I peptide-loading complex 总被引:3,自引:0,他引:3
Many viral proteins modulate class I expression, yet, in general, their mechanisms of specific class I recognition are poorly understood. The mK3 protein of gamma(2)-Herpesvirus 68 targets the degradation of nascent class I molecules via the ubiquitin/proteasome pathway. Here, we identify cellular components of the MHC class I assembly machinery, TAP and tapasin, that are required for mK3 function. mK3 failed to regulate class I in TAP- or tapasin-deficient cells, and mK3 interacted with TAP/tapasin, even in the absence of class I. Expression of mK3 resulted in the ubiquitination of TAP/tapasin-associated class I, and mutants of class I incapable of TAP/tapasin interaction were unaffected by mK3. Thus, mK3 subverts TAP/tapasin to specifically target class I molecules for destruction. 相似文献
993.
Entirely automated quantification of human immunodeficiency virus type 1 (HIV-1) RNA in plasma by using the ultrasensitive COBAS AMPLICOR HIV-1 monitor test and RNA purification on the MagNA pure LC instrument 下载免费PDF全文
The ultrasensitive COBAS AMPLICOR HIV-1 Monitor test was complemented with automated RNA purification on the MagNA Pure LC instrument. This enabled entirely automated ultrasensitive assessment of viral loads in human immunodeficiency virus type 1 (HIV-1)-infected individuals. The detection limit of the fully automated assay and the viral load measurements in 80 clinical samples were found to be in good agreement with those of the conventional ultrasensitive COBAS AMPLICOR HIV-1 Monitor test. The fully automated assay showed markedly reduced hands-on time and was found to be suitable for the routine assessment of HIV-1 viral loads in a clinical diagnostic laboratory. 相似文献
994.
Sandmire HF 《Obstetrics and gynecology》2003,101(4):811;author reply 812-811;author reply 813
995.
Valensise H Larciprete G Vasapollo B Novelli GP Menghini S di Pierro G Arduini D 《European journal of obstetrics, gynecology, and reproductive biology》2002,103(2):130-135
OBJECTIVE: The hypothesis was that fasting C-peptide and insulin values, during an oral glucose tolerance test (OGTT), might allow an estimation of the increased risk for gestational hypertension (GH) and fetal macrosomia. STUDY DESIGN: Two-hundred and six consecutive patients were submitted to an OGTT. Thirty-five developed gestational hypertension and 29 delivered large-for-gestational-age (LGA) newborns. Plasma glucose levels (mg/dl) and insulin levels (microU/ml) were measured fasting and after 60, 120 and 180 min C-peptide fasting levels (ng/ml) were also measured. RESULTS: Twenty-five patients were excluded, 181 were enrolled. According to the OGTT, 143 patients were classified as normal, 26 were found affected by gestational diabetes (GD) mellitus, and 12 had impaired gestational glucose tolerance (IGGT). Hypertensive women exhibited higher 60 and 120 min insulin values than the normotensive group (128.3+/-69.9 microU/ml versus 86.2+/-58.3 microU/ml, P<0.05; 104.9+/-66.4 microU/ml versus 78.7+/-56.5 microU/ml, P<0.05).C-peptide cut-off at 2.9 ng/ml resulted predictive for patients delivering large-for-gestational-age newborns (OR=3.42, 95% CI=1.59-7.39). CONCLUSIONS: C-peptide and insulin may be used as indicators of risk for the development of complications in late pregnancy. 相似文献
996.
Cerebrospinal fluid shunt survival and etiology of failures: a seven-year institutional experience 总被引:15,自引:0,他引:15
McGirt MJ Leveque JC Wellons JC Villavicencio AT Hopkins JS Fuchs HE George TM 《Pediatric neurosurgery》2002,36(5):248-255
BACKGROUND: Innovations in shunt technology and neuroendoscopy have been increasingly applied to shunt management. However, the relative life span of shunts and the etiology of shunt failure have not been characterized recently. METHODS: We reviewed the records of all shunting procedures at our institution between January 1992 and December 1998. Independent predictors of shunt failure were analyzed via multivariate Cox regression analysis in 836 shunting procedures. Independent predictors of the etiology of failure (infection, proximal obstruction, distal malfunction) were analyzed via multivariate logistic regression analysis in the 383 shunts which failed. RESULTS: A total of 353 pediatric patients underwent 308 shunt placements and 528 revisions. The risk (hazard ratio; HR) of shunt failure decreased as a function of time in both primary placements and revised shunts. In failed shunts, the odds of infection decreased 4-fold per year of shunt function, while the odds of distal malfunction increased 1.45-fold per year. Increasing number of shunt revisions (HR 1.31, p < 0.05), decreasing patient age in years (HR 1.04, p < 0.001), gestational age <40 weeks (HR 2.15, p < 0.001) but not the etiology of hydrocephalus were associated with an increased risk of shunt failure. Revisions versus primary placements, Dandy-Walker cysts and gestational age <40 weeks were independently associated with proximal, distal and infectious causes of failure, respectively. CONCLUSIONS: The long-term shunt revision rates observed here are similar to those reported over the past 2 decades. Shunt life span remains poorer in shunt revisions and in younger patients. Patient characteristics may suggest a specific risk and mechanism of failure, aiding in the long-term management of shunted hydrocephalus. 相似文献
997.
Disruption of the endometrial-myometrial border during pregnancy as a risk factor for adenomyosis 总被引:3,自引:0,他引:3
Curtis KM Hillis SD Marchbanks PA Peterson HB 《American journal of obstetrics and gynecology》2002,187(3):543-544
We assessed surgical disruption of the endometrial-myometrial border during pregnancy as a risk factor for adenomyosis in a cohort of 1850 women undergoing hysterectomy during 1978 to 1981. Women who had 3 or more abortions when sharp curettage was common were at increased risk for adenomyosis; women who had curettage procedures or cesarean deliveries were not. 相似文献
998.
Autofluorescence spectroscopy for the diagnosis of cervical intraepithelial neoplasia 总被引:2,自引:0,他引:2
Weingandt H Stepp H Baumgartner R Diebold J Xiang W Hillemanns P 《BJOG : an international journal of obstetrics and gynaecology》2002,109(8):947-951
Objective To assess the feasibility of autofluorescence spectroscopy in the diagnosis of cervical intraepithelial neoplasia (CIN) using broadband light excitation.
Design Feasibility study.
Setting Colposcopy clinic of an university hospital.
Population Sixty-eight patients at risk for CIN.
Methods After excitation with a broadband light between 375 and 440 nm, spectral distribution of native tissue fluorescence (autofluorescence) was acquired from 685 cervical sites for the localisation and differentiation of CIN, and compared with colposcopically directed biopsy and human papillomavirus (HPV) DNA testing.
Main outcome measure Detection of CIN.
Results The evaluation of spectral measurements revealed significantly lower autofluorescence values for CIN 3 lesions compared with normal tissue ( P < 0.001 ), and compared with CIN 1 or CIN 2 ( P < 0.002 ). High grade CIN lesions (CIN 2/3) presented with a significant reduced autofluorescence compared with CIN 1 ( P < 0.002 ). Patients with a positive HPV DNA testing showed a significantly lower autofluorescence than patients tested negative for HPV DNA ( P < 0.05 ). Severe inflammation such as chronic cervicitis may lead to false positive results.
Conclusions Autofluorescence spectroscopy represents an interesting approach for the detection of cervical neoplasia. Using an excitation wavelength band between 375 and 440 nm, significant differences between normal and precancerous lesions of the cervix can be seen. 相似文献
Design Feasibility study.
Setting Colposcopy clinic of an university hospital.
Population Sixty-eight patients at risk for CIN.
Methods After excitation with a broadband light between 375 and 440 nm, spectral distribution of native tissue fluorescence (autofluorescence) was acquired from 685 cervical sites for the localisation and differentiation of CIN, and compared with colposcopically directed biopsy and human papillomavirus (HPV) DNA testing.
Main outcome measure Detection of CIN.
Results The evaluation of spectral measurements revealed significantly lower autofluorescence values for CIN 3 lesions compared with normal tissue ( P < 0.001 ), and compared with CIN 1 or CIN 2 ( P < 0.002 ). High grade CIN lesions (CIN 2/3) presented with a significant reduced autofluorescence compared with CIN 1 ( P < 0.002 ). Patients with a positive HPV DNA testing showed a significantly lower autofluorescence than patients tested negative for HPV DNA ( P < 0.05 ). Severe inflammation such as chronic cervicitis may lead to false positive results.
Conclusions Autofluorescence spectroscopy represents an interesting approach for the detection of cervical neoplasia. Using an excitation wavelength band between 375 and 440 nm, significant differences between normal and precancerous lesions of the cervix can be seen. 相似文献
999.
Schneckenburger H Hendinger A Sailer R Strauss WS Schmitt M 《Journal of biomedical optics》2002,7(3):410-416
The plasma membrane of Chinese hamster ovary cells was made permeable using the focused beam of an argon ion laser (488 nm) and phenol red as a light absorbing dye. Small circular dark spots on the cell surface appeared immediately after laser irradiation and disappeared within about 5 min. They were related to transient changes in membrane properties, which could be visualized using the fluorescent marker laurdan, and were probably due to a local increase in temperature. According to a colony forming assay, cell viability was maintained by using light doses up to 2.5 MJ/cm(2) applied for 1 s. In addition to measurements of the efflux of the cytoplasmic marker calcein, cell transfection using a green fluorescent protein (GFP) coding plasmid was studied: brightly fluorescent GFP with an emission maximum around 510 nm was observed within part of the cells after 24 h. The transfection rates after laser irradiation were around 30% for younger subcultures and less than 10% for aging cells. This may be due to age dependent changes in the phase transition of membrane lipids from gel phase to liquid crystalline phase. High transfection rates, visual control and universality towards various cell lines are possibly the main advantages of laser-assisted optoporation in comparison with presently existing methods of cell transfection. 相似文献
1000.
Baldock PA Sainsbury A Couzens M Enriquez RF Thomas GP Gardiner EM Herzog H 《The Journal of clinical investigation》2002,109(7):915-921
Neuropeptide Y (NPY) is a downstream modulator of leptin action, possibly at the level of the arcuate nucleus where NPY neurons are known to express both leptin receptors and Y2 receptors. In addition to the well-described role of NPY and leptin in energy balance and obesity, intracerebroventricular administration of NPY or leptin also causes bone loss. Here we show that Y2 receptor-deficient mice have a twofold increase in trabecular bone volume as well as greater trabecular number and thickness compared with control mice. We also demonstrate that central Y2 receptors are crucial for this process, since selective deletion of hypothalamic Y2 receptors in mature conditional Y2 knockout mice results in an identical increase in trabecular bone volume within 5 weeks. This hypothalamus-specific Y2 receptor deletion stimulates osteoblast activity and increases the rate of bone mineralization and formation, with no effect on osteoblast or osteoclast surface measurements. The lack of any changes in plasma total calcium, leptinemia, or hypothalamo-pituitary-corticotropic, -thyrotropic, -somatotropic, or -gonadotropic output suggests that Y2 receptors do not modulate bone formation by humoral mechanisms, and that alteration of autonomic function through hypothalamic Y2 receptors may play a key role in a major central regulatory circuit of bone formation. 相似文献