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91.
We have examined 62 prostatic adenocarcinomas by conventional cytogenetic analysis. Most were primary cultures harvested in 14 days or less. The most consistent finding was a normal male diploid karyotype, found in 87% of all cells analyzed, and as the exclusive finding in 19 tumors. Nonrandom chromosomal changes included gain of chromosome 7 and loss of the Y chromosome. In addition, clonal gains of chromosomes 8, 12, and 18, and clonal losses of chromosomes 14 and 19 were noted in individual cases. Two structural clonal aberrations, a 9p+ in one case and a t(Y;22) (q11.2;p12) in another, were also seen. Ten of 62 cultures demonstrated chromosome instability, defined herein as nonclonal gain or loss of chromosomes in more than 10% of the metaphases examined from that culture. In those cases with nonclonal numerical aberrations, loss of chromosomes was more common than gain. The distribution of apparently random numeric abnormalities was similar to that of the clonal abnormalities in that the most frequent nonclonal gain was of chromosome 7 and the most frequent nonclonal loss was of the Y chromosome. Apparently random structural aberrations were observed in less than 1% of all analyzed cells. These included a 4p-,del(3)(q13), and t(1;11). The extent of apparently random aneuploidy suggests that chromosome instability characterizes cultured prostatic adenocarcinomas. An increase in the frequency of nonclonal aberrations may be an indicator of tumor origin in a predominantly diploid cell population. The coexistence of clonally aberrant, nonclonally aberrant, and normal diploid cells in culture may reflect heterogeneity of prostate tumors in vivo.  相似文献   
92.
Photodynamic therapy (PDT) is a clinical approach that utilizes light-activated drugs for the treatment of a variety of pathologic conditions. Human poorly (CNE2) and moderately differentiated (TW0-1) human nasopharyngeal carcinoma (NPC) cells undergo rapid apoptosis when treated with PDT sensitized with Hypocrellin A (HA) and Hypocrellin B (HB). It has been shown that these compounds have a strong photodynamic effect on tumors and viruses. The initiating events of PDT sensitized HA and HB-induced apoptosis are poorly defined. In the current study, we sought to determine whether Fas/FasL upregulation and involvement of mitochondrial events are an early event in HA and HB-treated PDT induced apoptosis. Loss of mitochondrial transmembrane potential, release of cytochrome c, involvement of caspases-8 and -3 and the status caspase-3 specific substrate PARP, were evaluated in PDT treated tumor cells. Photoactivation of HA and HB enhanced both CD95/CD95L expression and induced CD95-signaling dependent cell death in all tumor cell lines studied. CD95/ CD95L expression appeared within 2 h following light activation and appeared to be a primary event in PDT induced apoptosis. Furthermore, these results indicate that release of mitochondrial cytochrome c into the cytoplasm is a secondary event following the activation of initiator caspase-8 preceding caspase-3 activation, cleavage of PARP and DNA fragmentation. Cytochrome c appeared in the cytosol within 2-3 h post PDT. Cleavage of PARP was observed at 3-4 h following PDT and caspase-3 specific inhibitor DEVD-CHO and broad-spectrum caspases inhibitor z-VAD-fmk blocked caspase-3 activation and PARP cleavage suggesting that caspase-3 plays an important role in HA and HB-induced apoptosis.  相似文献   
93.
OBJECTIVES: The objective of this study is to examine whether configural alterations of faces affect early or late processing stages as a function of their familiarity and their level of representation in memory. We then sought to verify whether the structural encoding stage is susceptible to top-down influences. METHODS: Electrophysiologic and behavioral studies were undertaken, during which unknown and familiar faces were presented upright or upside-down with or without feature alterations. The subjects were asked to determine whether the faces were familiar or not. RESULTS: N170 and N360 amplitudes were larger for familiar faces as well as altered ones. A higher degree of familiarity decreased reaction times (RTs) and N360 latencies, but increased N170 latencies, whereas face alterations increased RTs and latencies of both components examined. However, familiarity interacted with altered face configurations only for RTs and the N170. SIGNIFICANCE: In the perceptual stage, familiar faces seem to develop a more elaborate type of processing because of top-down influences linked to the robust nature of their representations in memory. The more elaborate type of processing for familiar faces has advantageous consequences for the following steps of information processing, by facilitating access to structural representations in memory (N360) as well as the final step reflected by RTs. The fact that configural alterations cause different effects for familiar as opposed to unfamiliar faces indicate that these stimuli are processed in a qualitatively different manner and solicit different representations in memory.  相似文献   
94.
Polymers can be treated with an ozone/oxygen mixture to create peroxide and hydroperoxide groups on the polymer chain. These heat-sensitive functional groups can serve to initiate radical polymerization of vinyl monomers to form graft copolymers. The efficiency and the decomposition rate constant of an ozonized ethylene-vinyl acetate copolymer (EVA) are determined using the polymerization rate of styrene. The thermal polymerization of styrene is studied in the presence of non-ozonized EVA. The thermal polymerization has no effect on the polymerization of styrene at the beginning of the reaction. Transfer reactions between the growing polystyrene radical and the EVA chain are negligible. The activation energy of the decomposition rate of ozonized EVA is calculated and reaches 46 kJ/mol. The entropy variation of the decomposition reaction is also calculated. The result obtained shows an important decrease (?45 cal · mol?1 · K?1) of the entropy which is opposite to the common behaviour (?6 to +13 cal · mol?1 · K?1) expected. The efficiency observed for the ozonized polymers is low and reaches only 20% at 100°C, this can be explained by the lack of mobility of the created radicals.  相似文献   
95.
Elrefaei M  El-Sheikh N  Kamal K  Cao H 《Immunology》2003,110(4):513-518
Factors that influence the generation and maintenance of memory CD8+ T cells are not fully understood. The homeostasis of memory T cells is highly dynamic and tightly regulated by various stimuli, including cytokines and antigen-major histocompatibility complex ligands. We characterized the hepatitis C virus (HCV)-specific CD8+ T-cell responses in a cohort of HCV-infected individuals with or without Schistosoma mansoni co-infection from Egypt. We observed a significantly decreased CD27- CD28- (late differentiated) memory T-cell population in the HCV co-infected individuals compared to those with HCV infection alone. In contrast, there was no significant difference in the CD27+ CD28+ (early differentiated) memory T cells between the two groups. Analysis of human cytomegalovirus-specific CD8+ T-cell responses in the same individuals failed to reveal a similar pattern of altered memory T-cell differentiation. Thus, S. mansoni co-infection targets a specific subset of memory CD8+ T cells in HCV infection.  相似文献   
96.
Free-roaming camels, especially those crossing national borders, pose a high risk for spreading Middle East respiratory syndrome coronavirus (MERS-CoV). To prevent outbreaks, active surveillance is necessary. We found that a high percentage of dromedaries in Tunisia are MERS-CoV seropositive (80.4%) or actively infected (19.8%), indicating extensive MERS-CoV circulation in Northern Africa.  相似文献   
97.
BackgroundDuctal prostate adenocarcinoma (DAC) is a rare, aggressive, histologic variant of prostate cancer that is treated with conventional therapies, similar to high-risk prostate adenocarcinoma (PAC).ObjectiveTo assess the outcomes of men undergoing definitive therapy for DAC or high-risk PAC and to explore the effects of androgen deprivation therapy (ADT) in improving the outcomes of DAC.Design, setting, and participantsA single-center retrospective review of all patients with cT1–4/N0–1 DAC from 2005 to 2018 was performed. Those undergoing radical prostatectomy (RP) or radiotherapy (RTx) for DAC were compared with cohorts of high-risk PAC patients.Outcome measurements and statistical analysisMetastasis-free survival (MFS) and overall survival (OS) rates were analyzed using Kaplan-Meier and Cox regression models.Results and limitationsA total of 228 men with DAC were identified; 163 underwent RP, 34 underwent RTx, and 31 had neoadjuvant therapy prior to RP. In this study, 163 DAC patients and 155 PAC patients undergoing RP were compared. Similarly, 34 DAC patients and 74 PAC patients undergoing RTx were compared. DAC patients undergoing RP or RTx had worse 5-yr MFS (75% vs 95% and 62% vs 93%, respectively, p < 0.001) and 5-yr OS (88% vs 97% and 82% vs 100%, respectively, p < 0.05) compared with PAC patients. In the 76 men who received adjuvant/salvage ADT after RP, DAC also had worse MFS and OS than PAC (p < 0.01). A genomic analysis revealed that 10/11 (91%) DACs treated with ADT had intrinsic upregulation of androgen-resistant pathways. Further, none of the DAC patients (0/15) who received only neoadjuvant ADT prior to RP had any pathologic downgrading. The retrospective nature was a limitation.ConclusionsMen undergoing RP or RTx for DAC had worse outcomes than PAC patients, regardless of the treatment modality. Upregulation of several intrinsic resistance pathways in DAC rendered ADT less effective. Further evaluation of the underlying biology of DAC with clinical trials is needed.Patient summaryThis study demonstrated worse outcomes among patients with ductal adenocarcinoma of the prostate than among high-grade prostate adenocarcinoma patients, regardless of the treatment modality.  相似文献   
98.
Avanafil is a highly selective and potent oral phosphodiesterase type 5 inhibitor. However, its impact on the soluble markers of endothelial function has not been investigated yet. This study was conducted to assess the effect of daily avanafil on the endothelial markers' serum level and erectile function in patients with erectile dysfunction. In this work, we randomly divided 140 males with erectile dysfunction and other diseases commonly associated with endothelial dysfunction like diabetes mellitus, hypertension and dyslipidaemia into two equal groups: treatment group, treated with 50mg daily oral avanafil, and control group, treated with placebo. The International Index of Erectile Function-5 score and the serum levels of nitric oxide, cyclic guanosine monophosphate and endothelin-1 as markers of endothelial function were measured at baseline and after four weeks of treatment in both groups. At the end of treatment period, those randomised to avanafil achieved statistically significant improvement in erectile function, nitric oxide, cyclic guanosine monophosphate and endothelin-1 levels from baseline versus placebo regardless the type and duration of associated comorbidity as well as the duration and severity of erectile dysfunction. These results permitted us to suggest that daily avanafil can improve the impaired endothelial function associated with the erectile dysfunction.  相似文献   
99.
In this study, we investigated the prevalence of sexual dysfunction among males with advanced chronic kidney disease and the effect of treating hyperprolactinemia among these patients. In this prospective study, patients were assessed with history, physical examination, hormonal assessment, and two questionnaires, IIEF and AIPE. Patients with hyperprolactinemia received treatment with cabergoline 0.5 mg once per week for 6 months and were re-evaluated. A total of 102 patients were included in this study, 75 (73.53%) were on hemodialysis, 13 (12.75%) on peritoneal dialysis and 14 (13.73%) on medical treatment alone. Ninety (88.24%) patients had premature ejaculation, 85 (83.33%) had anything from mild-to-moderate-to-severe erectile dysfunction. The incidence of hypogonadism and hyperprolactinemia was 34.4%. Patients treated with cabergoline (n = 26) showed a significant increase in LH levels (p = .003) and a significant decrease in prolactin levels (p = .003). Testosterone levels and the incidence of erectile dysfunction or premature ejaculation did not improve significantly. There is a high incidence of sexual dysfunction among patients. Treatment of hyperprolactinemia is effective in correcting prolactin levels, but does not improve erectile dysfunction or premature ejaculation. Therefore, treating hyperprolactinemia is not an overall effective treatment for erectile dysfunction in these patients.  相似文献   
100.
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