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81.
82.
OBJECTIVES: Synergism between gemcitabine and cisplatin is supported by preclinical and clinical data. The present study explores the efficacy of a biweekly regimen in platinum-resistant/refractory, paclitaxel-pretreated ovarian and peritoneal cancer. METHODS: 50 paclitaxel-pretreated patients with platinum-resistant/refractory ovarian or peritoneal carcinoma who had previously received paclitaxel chemotherapy, were treated with six cycles of gemcitabine 1000 mg/m(2) followed by cisplatin 40 mg/m(2) on days 1 and 15, repeated every 4 weeks. RESULTS: The median platinum-free interval (PFI) was 4 months while the median number of previous treatment lines was 2. Chemotherapy was well tolerated. Objective responses were observed in 31.5% of evaluable patients (n=35). CA125 response was observed in 68% of patients with elevated CA125 (n=41). Median overall survival (OS) was 13.2 months (95% Confidence Interval, CI: 10.2-16.2) while progression-free survival (PFS) was 4.9 months (95%CI: 3.5-6.4). A PFI of less than 3 months was associated with lower objective response rates (15.8% versus 50%, p=0.03). CONCLUSIONS: Biweekly gemcitabine and cisplatin is feasible for patients with platinum-resistant ovarian or peritoneal cancer and is associated with a favorable toxicity profile. In a population with recent exposure to platinum, a PFI of less than 3 months was the major factor influencing response to chemotherapy.  相似文献   
83.
OBJECTIVES: Vascular endothelial growth factors A and B (VEGF-A and VEGF-B) play a major role in angiogenesis and activate VEGF receptor 1 (VEGFR-1). However, the clinicopathologic and clinical value of VEGF-B and VEGFR-1 in invasive breast carcinoma remains unclear. METHODS: We immunohistochemically examined the expression pattern of VEGF-A, VEGF-B and VEGFR-1 in 177 invasive breast carcinomas in relation to clinicopathological parameters, p53, c-erbB2 proteins expression and patients' survival. RESULTS: VEGF-A, VEGF-B and VEGFR-1 were immunodetected predominantly in the cytoplasm of the malignant cells. None of the studied markers correlated with any of the clinicopathological parameters, other than stromal VEGFR-1 which inversely correlated with PR (p=0.021). Cancerous VEGF-A and stromal VEGFR-1 were positively related to p53 (p=0.016 and p=0.033, respectively). Cancerous VEGF-B was positively associated with c-erbB-2 (p=0.045) and was found to exert an unfavorable impact on both disease-free and the overall survival of the node-positive patients (p=0.05 and p=0.029, respectively). Cancerous VEGFR-1 was recognized as being an independent poor prognostic indicator (p=0.037). CONCLUSION: These findings suggest that, while VEGF-B seems to be useful as a prognostic indicator only in node-positive patients, VEGFR-1 may be an independent poor prognosticator in patients with invasive breast carcinoma.  相似文献   
84.
In this article, a novel technique for assessment of obstructive sleep apnea (OSA) during wakefulness is proposed; the technique is based on tracheal breath sound analysis of normal breathing in upright sitting and supine body positions. We recorded tracheal breath sounds of 17 non-apneic individuals and 35 people with various degrees of severity of OSA in supine and upright sitting positions during both nose and mouth breathing at medium flow rate. We calculated the power spectrum, Kurtosis, and Katz fractal dimensions of the recorded signals and used the one-way analysis of variance to select the features, which were statistically significant between the groups. Then, the maximum relevancy minimum redundancy method was used to reduce the number of characteristic features to two. Using the best two selected features, we classified the participant into severe OSA and non-OSA groups as well as non-OSA or mild vs. moderate and severe OSA groups; the results showed more than 91 and 83% accuracy; 85 and 81% specificity; 92 and 95% sensitivity, for the two types of classification, respectively. The results are encouraging for identifying people with OSA and also prediction of OSA severity. Once verified on a larger population, the proposed method offers a simple and non-invasive screening tool for prediction of OSA during wakefulness.  相似文献   
85.

Objectives

The aim of the present study was to evaluate how sociodemographic parameters, lifestyle indicators and intensity of climacteric symptoms affect the quality of life (QOL) of Greek community dwelling middle-aged women.

Study design

This population survey included 1140 middle-aged women aged 45–65 who represented 1% of the whole female population of this age group in Greece, stratified by residential area.

Main outcome measures

Participants were asked to complete a questionnaire concerning sociodemographic and anthropometric parameters, medical history, the Utian quality of life (QOL) scale and the Greene climacteric scale rating menopausal symptoms.

Results

In the univariate analysis, normal body mass index, married status, higher education, employment, good financial status, physical exercise and a high calcium diet were associated with higher total QOL scores (p-value < 0.001). Multivariate regression analysis showed that higher total QOL scores were predicted by being married (separated/divorced/widowed: beta = −3.17, p-value = 0.008), by physical exercise (beta = 4.84 and beta = 4.57 for 1–3 h and >3 h per week respectively, p-value < 0.001) and by a good financial status (beta = 7.05, p-value < 0.001), while a higher score in the Greene scale resulted in lower total QOL scores (beta = −0.77, p-value < 0.001). Women with a better QOL were more health conscious and more probable to have utilized the public health preventive resources.

Conclusions

Menopause as a life event has no effect on the QOL of Greek middle-aged women. On the contrary, the presence and intensity of climacteric symptoms have a negative impact on all aspects of QOL. Marital and financial status, as well as physical exercise, are also significant predictors of QOL.  相似文献   
86.
Comorbidity of cognitive and stress disorders is a common clinical sequel of traumatic brain injury (TBI) that is essentially determined by the site and severity of the insult, but also by the extent of the ensuing neuroinflammatory response. The present study sought to examine the late effects of closed-head TBI on memory function and anxiety in mice, in order to further examine the potential efficacy of an acute anti-inflammatory treatment with minocycline. The mouse model of closed-head injury by mechanical percussion was applied on anesthetized Swiss mice. The treatment protocol included three injections of minocycline (i.p.) at 5 min (90 mg/kg), 3 h and 9 h (45 mg/kg) post-TBI. The Novel Object Recognition Test as well as the Elevated Plus Maze (EPM) and Elevated Zero Maze (EZM) tasks were employed to assess post-TBI memory and anxiety respectively. Our results revealed a recognition memory deficit that was significant up to at least 13 weeks post-TBI. However, neither EPM nor EZM revealed any alteration in post-TBI anxiety levels albeit some mild disinhibition. Most importantly, minocycline was able to attenuate the memory impairment in an effective and lasting manner, highlighting its therapeutic potential in TBI.  相似文献   
87.
Primary congenital glaucoma (PCG) is an autosomal recessive disorder caused predominantly by mutations in the CYP1B1 gene. A total of five frequent single nucleotide polymorphisms (SNPs) have been identified in the coding sequence of CYP1B1: rs10012C>G (p.R48G), rs1056827G>T (p.A119S), rs1056836C>G (p.V432L), rs1056837C>T (p.D449D), and rs1800440A>G (p.N453S). We performed a functional characterization of four common CYP1B1 variants presenting different coding SNP haplotypes (RAVDN, GSLDN, RALDS, and RALDN) and five CYP1B1 mutations reported for PCG patients: c.182G>A (p.G61E), c.608A>G (p.N203S), c.1033_1035del (p.L343del), c.241 T>A (p.Y81N), and c.685G>A (p.E229 K). Each mutation was embedded in its corresponding background SNP haplotype. The common variants revealed variation in enzymatic activity; among them, RAVDN showed the highest activity. Mutants p.G61E, p.N203S, and p.L343del each revealed a residual activity (<10%) of their respective haplotype. The microsomal CYP1B1 abundance relative to total protein also showed variation in common variants and a significant reduction in p.L343del, p.Y81N, and p.E229 K. The free energy of folding (DeltaDeltaG) values suggest that the lower stability of the mutants is one key property leading to the experimentally observed lower protein abundance. Our new measure of relative enzymatic activity (U/mg total protein), which combines activity and abundance values, was significantly lower for all five mutations compared to the corresponding background haplotype. We classified p.Y81N and p.E229 K not as mutations but as hypomorphic alleles, since their relative activity values are intermediate between bona fide mutations and the common variant with the lowest activity (RALDS). We propose that CYP1B1 mutations can act by either reducing enzymatic activity (p.G61E and p.N203S), reducing the abundance of the enzyme (p.Y81N and p.E229 K), or both (p.L343del).  相似文献   
88.
The aim of the present study was to investigate the putative cooperative effects of transforming growth factor beta (TGF-beta) and glial cell line-derived neurotrophic factor (GDNF) family ligands in the differentiation of midbrain progenitors toward a dopaminergic phenotype. Therefore, a mouse midbrain embryonic day (E) 12 neurospheres culture was used as an experimental model. We show that neurturin and persephin (PSPN), but not GDNF, are capable of transient induction of dopaminergic neurons in vitro. This process, however, requires the presence of endogenous TGF-beta. In contrast, after 8 days in vitro GDNF rescued the TGF-beta neutralization-dependent loss of the TH-positive cells. In vivo, at E14.5, no apparent phenotype concerning dopaminergic neurons was observed in Tgf-beta2(-/-)/gdnf(-/-) double mutant mice. In vitro, combined TGF-beta/PSPN treatment achieved a yield of approximately 20% TH-positive cells that were less vulnerable against 1-methyl-4-phenyl pyridinium ion toxicity. The underlying TGF-beta/PSPN differentiation signaling is receptor-mediated, involving p38 mitogen-activated protein kinase and phosphatidylinositol 3-kinase pathways. These results indicate that phenotype induction and survival of fully differentiated neurons are accomplished through distinct pathways and individual factor requirement. TGF-beta is required for the induction of dopaminergic neurons, whereas GDNF is required for regulating and/or maintaining a differentiated neuronal phenotype. Moreover, this study suggests that the combination of TGF-beta with PSPN is a potent inductive cocktail for the generation of dopaminergic neurons that should be considered in tissue engineering and cell replacement therapies for Parkinson's disease.  相似文献   
89.
90.
Tzelepi V, Karlou M, Wen S, Hoang A, Logothetis C, Troncoso P & Efstathiou E
(2011) Histopathology 58, 1037–1047
Expression of hedgehog pathway components in prostate carcinoma microenvironment: shifting the balance towards autocrine signalling Aims: The hedgehog (Hh) signalling pathway has been implicated in the pathogenesis and aggressiveness of prostate cancer through epithelial–mesenchymal interactions. The aim of this study was to elucidate the cell‐type partitioned expression of the Hh pathway biomarkers in the non‐neoplastic and tumour microenvironments and to correlate it with the grade and stage of prostate cancer. Methods and results: Expression of the Hh pathway components (Shh, Smo, Ptch, Gli1) in the microenvironment of non‐neoplastic peripheral zone (n = 119), hormone‐naive primary prostate carcinoma (n = 141) and castrate‐resistant bone marrow metastases (n = 53) was analysed using immunohistochemistry in tissue microarrays and bone marrow sections. Results showed that epithelial Shh, Smo and Ptch expression was up‐regulated, whereas stromal Smo, Ptch, and Gli1 expression was down‐regulated in prostate carcinomas compared to non‐neoplastic peripheral zone tissue. Ptch expression was modulated further in high‐grade and high‐stage primary tumours and in bone marrow metastases. Hh signalling correlated with ki67 and vascular endothelial growth factor (VEGF) but not with CD31 expression. Conclusion: Our results highlight the importance of Hh‐mediated epithelial–mesenchymal interactions in the non‐neoplastic prostate and imply that shifting the balance from paracrine towards autocrine signalling is important in the pathogenesis and progression of prostate carcinoma.  相似文献   
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