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991.
OBJECTIVES: To evaluate the effectiveness and morbidity of salvage brachytherapy for locally recurrent or persistent prostate cancer after radiotherapy failure. METHODS: In this retrospective study, 49 patients of median age 73.3 years (range 52.9 to 86.9) with biopsy-proven localized prostate cancer underwent interactive transperineal fluoroscopic-guided and biplane ultrasound-guided brachytherapy with either iodine 125 or palladium 103 after prior radiotherapy failure. Post-treatment follow-up was conducted for a median of 64.1 months (range 26.6 to 96.8) and included clinical assessment of disease status, assays of serum prostate-specific antigen (PSA) levels, and documentation of treatment-related symptoms and complications. Determination of biochemical treatment failure was based on two successive rising PSA values above the post-treatment PSA nadir value. RESULTS: The actuarial rate of local prostate cancer control was 98% (95% confidence interval [CI] 94% to 99%). Actuarial disease-specific survival at 3 and 5 years was 89% (95% CI 73% to 96%) and 79% (95% CI 58% to 91%), respectively. At 3 and 5 years, actuarial biochemical disease-free survival was 48% (95% CI 32% to 63%) and 34% (95% CI 17% to 51%), respectively. Post-treatment PSA nadir was found to be a significant predictor of biochemical disease-free survival. Actuarial biochemical disease-free survival of patients who achieved a PSA nadir less than 0.5 ng/mL was 77% (95% CI 53% to 90%) and 56% (95% CI 25% to 78%) at 3 and 5 years, respectively. Of 49 patients, 23 (47%) achieved a post-treatment PSA nadir less than 0.5 ng/mL. The incidence of serious complications after salvage brachytherapy, such as incontinence and rectal complications, was lower than that reported after other types of salvage procedures. CONCLUSIONS: Interactive transperineal fluoroscopic-guided and biplane ultrasound-guided brachytherapy is a novel, potentially curative salvage modality for patients in whom prior radiotherapy failed. In a population of patients with poor prognosis, this modality was associated with a high rate of local prostate cancer control and a 34% actuarial rate of biochemical disease-free survival at 5 years. The incidence of major complications after salvage brachytherapy appears to be lower than that after other potentially curative salvage procedures, such as radical prostatectomy and cryoablation. Salvage brachytherapy warrants further investigation.  相似文献   
992.
OBJECTIVE: To determine the prevalence of common mental disorders (anxiety and depression) and help seeking behaviour in African Caribbeans and white Europeans. DESIGN: Two phase survey in a general population sample. The first phase comprised screening with the 12 item general health questionnaire; the second phase was standardised psychiatric assessment and interview about help seeking. SETTING: People registered with four general practices in central Manchester. PARTICIPANTS: Of 1467 people randomly selected from family health services authority lists, 864 were still resident. 337 African Caribbeans and 275 white Europeans completed the screening phase (response rate 71%); 127 African Caribbeans and 103 white Europeans were interviewed in the second phase. MAIN OUTCOME MEASURES: One month period prevalence of anxiety and depressive disorders in each ethnic group. RESULTS: 13% of African Caribbeans (95% confidence interval 10% to 16%) and 14% (10% to 18%) of white Europeans had one or more disorder. Anxiety disorders were significantly less common among African Caribbeans (3% (1% to 5%) v 9% (6% to 12%) in white Europeans). Depressive disorders were significantly more common among African Caribbean women than white women (difference 8% (1% to 15%)). Medical help seeking was similar in the two groups, but African Caribbeans with mental disorders were more likely to seek additional help from non-medical sources (12/29 v 5/29, P=0.082). CONCLUSIONS: In an inner city setting the prevalence of common mental disorders is similar in these two ethnic groups.  相似文献   
993.
994.
There is ample evidence suggesting (e.g., A. Tesser & S. Rosen, 1975) that people are reluctant to transmit bad news. Research on rumors, on the other hand, suggests that people sometimes are less reluctant to transmit bad news. It is argued that differences between the 2 lines of research include the definitiveness of the consequences of the news and the relationship between communicator and recipient. The influence of these 2 factors on news transmission was investigated in 3 experiments. Results showed that bad news with indefinite consequences was transmitted more often than bad news with definite consequences and that both kinds of bad news were transmitted more often if the recipient was a friend rather than a stranger. Differences in feelings of moral responsibility to transmit the news largely accounted for both effects. The 2 factors did not affect the likelihood of good news transmission. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
995.
The initial outgrowth of peripheral axons in developing embryos is thought to occur independently of neurotrophins. However, the degree to which peripheral neurons can extend axons and elaborate axonal arborizations in the absence of these molecules has not been studied directly because of exquisite survival requirements for neurotrophins at early developmental stages. We show here that embryonic sensory neurons from BAX-deficient mice survived indefinitely in the absence of neurotrophins, even in highly dissociated cultures, allowing assessment of cell autonomous axon outgrowth. At embryonic day 11 (E11)-E13, stages of rapid axon growth toward targets in vivo, Bax-/- sensory neurons cultured without neurotrophins were almost invariably unipolar and extended only a rudimentary axon. Addition of neurotrophins caused outgrowth of a second axon and a marked, dose-dependent elongation of both processes. Surprisingly, morphological responses to individual neurotrophins differed substantially. Neurotrophin-3 (NT-3) supported striking terminal arborization of subsets of Bax-/- neurons, whereas NGF produced predominantly axon elongation in a different subset. We conclude that axon growth in vitro is neurotrophin dependent from the earliest stages of sensory neuron development. Furthermore, neurotrophins support the appearance of distinct axonal morphologies that characterize different sensory neuron subpopulations.  相似文献   
996.
BACKGROUND: Inhibition of apoptosis, or programmed cell death, may be critical both in the development of cancer and in determining response to therapy. The authors examined the expression of two related apoptotic inhibitors, Bcl-2 and Bcl-xL, in pretreatment biopsies from a series of 42 patients with squamous cell carcinoma of the head and neck. The observed pattern of apoptotic inhibitor expression was compared with that of the p53 gene product, another factor implicated in carcinogenesis and therapeutic responsiveness. METHODS: Formalin fixed, paraffin embedded tumor biopsies from 42 patients with locally advanced squamous cell carcinoma of the head and neck were analyzed by immunohistochemistry using antibodies specific for Bcl-xL, Bcl-2, and p53. Measures of clinical outcome, including disease specific survival and overall survival, were compared among the groups. RESULTS: The majority of the tumors demonstrated enhanced expression of either Bcl-2 or Bcl-xL compared with surrounding normal epithelium. Fifty-two percent of the tumors had up-regulated Bcl-xL, and 17% had up-regulated Bcl-2. There was no overlap between these groups. Expression of Bcl-2, but not Bcl-xL, was correlated with improved disease specific survival. Immunohistochemically detectable p53 expression (48% of tumors) was not found to correlate with expression of either Bcl-xL or Bcl-2 and, in this series, was not a predictor of clinical outcome. CONCLUSIONS: These results suggest that disruption of apoptotic control pathways is an important event in the evolution of squamous cell carcinoma of the head and neck. A common mechanism for this disruption involves overexpression of Bcl-xL, Patients whose tumors demonstrate Bcl-2 positivity, even with locoregionally advanced disease, appear to have a high likelihood of cure with aggressive combined modality therapy and may be treated successfully with less toxic therapy.  相似文献   
997.
Geminiviruses are plant viruses with circular single-stranded DNA (ssDNA) genomes encapsidated in double icosahedral particles. Tomato leaf curl geminivirus (ToLCV) requires coat protein (CP) for the accumulation of ssDNA in protoplasts and in plants but not for systemic infection and symptom development in plants. In the absence of CP, infected protoplasts accumulate reduced levels of ssDNA and increased amounts of double-stranded DNA (dsDNA), compared to accumulation in the presence of wild-type virus. To determine whether the gene 5 protein (g5p), a ssDNA binding protein from Escherichia coli phage M13, could restore the accumulation of ssDNA, ToLCV that lacked the CP gene was modified to express g5p or g5p fused to the N-terminal 66 amino acids of CP (CP66:6G:g5). The modified viruses led to the accumulation of wild-type levels of ssDNA and high levels of dsDNA. The accumulation of ssDNA was apparently due to stable binding of g5p to viral ssDNA. The high levels of dsDNA accumulation during infections with the modified viruses suggested a direct role for CP in viral DNA replication. ToLCV that produced the CP66:6G:g5 protein did not spread efficiently in Nicotiana benthamiana plants, and inoculated plants developed only very mild symptoms. In infected protoplasts, the CP66:6G:g5 protein was immunolocalized to nuclei. We propose that the fusion protein interferes with the function of the BV1 movement protein and thereby prevents spread of the infection.  相似文献   
998.
Factors influencing glutamate uptake by astrocytes may indirectly influence neuronal survival. Elevated extracellular glutamate may be excitotoxic or may exacerbate neurodegeneration in various neurological diseases. By using a cell culture model, we have investigated the influence of astrocytic prion protein (PrPc) expression on glutamate uptake. Type 1 astrocytes expressing PrPc have a higher rate of Na+-dependent glutamate uptake than PrPc-deficient type 1 astrocytes. This difference is exacerbated when serum free media is used to culture the astrocytes. Further analysis suggested that a decrease in substrate affinity is responsible for the sensitivity of PrP-deficient astrocytic glutamate uptake to culture conditions. PrPc has been shown to bind copper. Greater sensitivity of cells to copper concentrations may be responsible for the decreased substrate affinity observed. PrPc-deficient cerebellar cells are more sensitive to glutamate toxicity in the presence of copper. These results show that glutamate uptake from astrocytes is dependent on PrPc expression which in turn may be related to copper metabolism.  相似文献   
999.
The tomato Cf-4 and Cf-9 genes map at a genetically complex locus on the short arm of chromosome 1 and confer resistance against Cladosporium fulvum through recognition of different pathogen-encoded avirulence determinants. Cf-4 and Cf-9 are members of a large gene family (Hcr9s, Homologues of Cladosporium fulvum resistance gene Cf-9), some of which encode additional distinct recognition specificities. A genetic analysis of the majority of Hcr9s suggests that their distribution is spatially restricted to the short arm of chromosome 1. Two loci of clustered Hcr9 genes have been analyzed physically that mapped distal (Northern Lights) and proximal (Southern Cross) to the Cf-4/9 locus (Milky Way). Sequence homologies between intergenic regions at Southern Cross and Milky Way indicate local Hcr9 duplication preceded cluster multiplication. The multiplication of clusters involved DNA flanking Hcr9 sequences as indicated by conserved lipoxygenase sequences at Southern Cross and Milky Way. The similar spatial distribution of Hcr9 clusters in different Lycopersicon spp. suggests Hcr9 cluster multiplication preceded speciation.  相似文献   
1000.
The prenyltransferase undecaprenyl pyrophosphate synthetase (di-trans,poly-cis-decaprenylcistransferase; EC 2.5.1.31) was purified from the soluble fraction of Escherichia coli by TSK-DEAE, ceramic hydroxyapatite, TSK-ether, Superdex 200, and heparin-Actigel chromatography. The protein was labeled with the photolabile analogue of the farnesyl pyrophosphate analogue (E, E)-[1-3H]-(2-diazo-3-trifluoropropionyloxy)geranyl diphosphate and was detected on a sodium dodecyl sulfate-polyacrylamide gel as a protein with an apparent molecular mass of 29 kDa. This protein band was cut out from the gel, trypsin digested, and subjected to matrix-assisted laser desorption ionization mass spectrometric analysis. Comparison of the experimental data with computer-simulated trypsin digest data for all E. coli proteins yielded a single match with a protein of unassigned function (SWISS-PROT Q47675; YAES_ECOLI). Sequences with strong similarity indicative of homology to this protein were identified in 25 bacterial species, in Saccharomyces cerevisiae, and in Caenorhabditis elegans. The homologous genes (uppS) were cloned from E. coli, Haemophilus influenzae, and Streptococcus pneumoniae, expressed in E. coli as amino-terminal His-tagged fusion proteins, and purified over a Ni2+ affinity column. An untagged version of the E. coli uppS gene was also cloned and expressed, and the protein purified in two chromatographic steps. We were able to detect Upp synthetase activity for all purified enzymes. Further, biochemical characterization revealed no differences between the recombinant untagged E. coli Upp synthetase and the three His-tagged fusion proteins. All enzymes were absolutely Triton X-100 and MgCl2 dependent. With the use of a regulatable gene disruption system, we demonstrated that uppS is essential for growth in S. pneumoniae R6.  相似文献   
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