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31.
32.
PurposeWe evaluated the prognostic value of 10 putative tumor markers by immunohistochemistry in a large multi-institutional cohort of patients with locally advanced urothelial cancer of the bladder (UCB) with the aim to validate their clinical value and to harmonize protocols for their evaluation.Materials and MethodsPrimary tumor specimens from 576 patients with pathologic (p)T3 UCB were collected from 24 institutions in North America and Europe. Three replicate 0.6-mm core diameter samples were collected for the construction of a tissue microarray (TMA). Immunohistochemistry (IHC) for 10 previously described tumor markers was performed and scored at 3 laboratories independently according to a standardized protocol. Associations between marker positivity and freedom from recurrence (FFR) or overall survival (OS) were analyzed separately for each individual laboratory using Cox regression analysis.ResultsThe overall agreement of the IHC scoring among laboratories was poor. Correlation among the 3 laboratories varied across the 10 markers. There was generally a lack of association between the individual markers and FFR or OS. The number of altered cell cycle regulators (p53, Rb, and p21) was associated with increased risk of cancer recurrence (P < 0.032). There was no clear pattern in the relationship between the percentage of markers altered in an 8-marker panel and FFR or OS.ConclusionsThis large international TMA of locally advanced (pT3) UCB suggests that altered expression of p53, Rb, and p21 is associated with worse outcome. However this study also highlights limitations in the reproducibility of IHC even in the most expert hands.  相似文献   
33.
This study evaluated functionalized dextran-derived hydrogels as BMP carriers using both in vitro and in vivo models. In vitro release kinetics indicated that dextran-derived hydrogels could retain rhBMP-2 growth factor in a variable manner depending on their functionalization ratio. The potential of these hydrogels when combined with extracted bovine BMP to enhance the bone formation was evaluated in a rat ectopic model. The largest osteoinduction was found when using hydrogels exhibiting the highest growth factor retention capacity. In addition, some implanted hydrogels demonstrated a capacity to induce an in-vivo calcification certainly related to their chemical composition. These properties make these materials interesting osteoconductive BMP carriers, allowing to decrease the amount of implanted factor required for bone regeneration.  相似文献   
34.
Symptoms of posttraumatic stress disorder (PTSD), psychosis, general psychopathology, role functioning, violence potential, and cognitive and emotional aspects of psychotic states were compared in three groups of veterans. Groups were defined on the basis of their DSM-IV diagnoses: Psychotic disorder and war-related PTSD, war-related PTSD without psychotic symptoms, and psychotic disorder without PTSD. Veterans with PTSD and a comorbid psychotic disorder showed significantly higher levels of positive symptoms of psychosis, general psychopathology, paranoia, and violent thoughts, feelings, and behaviors than the other two groups. These data show that patients with comorbid PTSD and psychotic disorder show levels of cognitive, emotional, and behavioral disturbance that far exceed the levels of disturbance seen in patients with PTSD without psychosis or in patients with psychotic disorder.  相似文献   
35.
The topographic and cellular distribution of the neurotensin-hydrolysing neutral metalloendopeptidase 24.16 (EC 3.4.24.16) was examined by light and electron microscopic immunohistochemistry in adult rat mesencephalon. Light microscopic immunoradioautography revealed a ubiquitous distribution of the enzyme throughout the midbrain with a relative enrichment of grey matter areas including the substantia nigra, ventral tegmental area, interfascicular nucleus, interpeduncular nucleus, rostral and caudal linear raphe nuclei, central grey and superficial grey of the superior colliculus. Peroxidase - antiperoxidase immunocytochemistry revealed two distinct cellular patterns of immunostaining: (1) weakly labelled neuronal perikarya more or less uniformly distributed throughout the grey matter, and (2) intensely immunoreactive glial cells heterogeneously distributed across the mesencephalon. Areas exhibiting dense concentrations of endopeptidase 24.16-containing glial cells corresponded to those displaying enhanced immunoreactivity in immunoradioautographs, suggesting that a major proportion of brain endopeptidase 24.16 is associated with glia. Electron microscopic examination of the substantia nigra and ventral tegmental area confirmed the association of the enzyme with a subpopulation of neurons and allowed identification of labelled glial cells as protoplasmic astrocytes. In neurons, endopeptidase 24.16 immunoreactivity was distributed heterogeneously within the cytoplasm of perikarya, dendrites and axons. Reaction product was also characteristically associated with restricted zones of the plasma membrane and underlying neuroplasm. In astrocytes, endopeptidase 24.16 immunostaining was densely and uniformly distributed throughout the cytoplasm of cell bodies and processes. Many of these processes were in direct contact with endopeptidase 24.16-immunopositive neuronal elements. The present results demonstrate that within the midbrain, endopeptidase 24.16 is both intracytoplasmic and membrane-associated in neurons and predominantly intracytoplasmic in glia. The presence of a large number of immunostained elements within areas of the midbrain known to display high levels of neurotensin and/or neurotensin receptors, together with the demonstrated catabolic activity of the enzyme on neurotensin in vitro, is consistent with a role of endopeptidase 24.16 in the functional inactivation of endogenous neurotensin in this region of the brain.  相似文献   
36.
: Accelerated fractionation was used to shorten overall treatment time to increase locoregional control and cause-specific survival.

: Eighty-eight patients with cancer of the esophagus ineligible for surgery were entered in the study between 1986 and 1993. Neoadjuvant chemotherapy was given to 64% of patients. Accelerated radiotherapy using the concomitant boost technique delivered a median dose of 65 Gy in a median overall treatment time of 32 days.

: The 3-year acturial local control rate in patients with T1, T2, and T3 tumors was 71%, 42%,and 33%, respectively. The 3-year cause-specific survival rates were 40%, 22%, and 6%, respectively. Sixteen percent of patients experienced Grafe 3 esophagitis. Late toxicity included esophageal stenosis and pulmonary fibrosis in 8% and 9% of the patients, respectively. Multivariate analysis demonstrated that T stage and overall treatment time were prognostic factors for cause-specific survival. T stage and neoadjuvant chemotherapy were independent prognostic factors for locoregional control.

: These findings suggest that accelerated giben in an overall treatment time of <35 days might be beneficial for easy-stage cancer of the esophagus. Neoadjuvant chemotherapy is not recommended, as it was a significant adverse prognostic factor in the multivariate analysis for local control. Accelerated fractionation can be carried out with modeate acure and late toxicity.  相似文献   

37.
Glucocorticoids are the consensus treatment for the prevention of respiratory distress in preterm infants, but there is evidence for increased incidence of neurodevelopmental disorders as a result of their administration. We administered dexamethasone (Dex) to developing rats at doses below or within the range of those used clinically, evaluating the effects on forebrain development with exposure in three different stages: gestational days 17-19, postnatal days 1-3, or postnatal days 7-9. At 24 h after the last dose, we evaluated biomarkers of neural cell acquisition and growth, synaptic development, neurotransmitter receptor expression, and synaptic signaling mediated by adenylyl cyclase (AC). Dex impaired the acquisition of neural cells, with a peak effect when given in the immediate postnatal period. In association with this defect, Dex also elicited biphasic effects on cholinergic presynaptic development, promoting synaptic maturation at a dose (0.05 mg/kg) well below those used therapeutically, whereas the effect was diminished or lost when doses were increased to 0.2 or 0.8 mg/kg. Dex given postnatally also disrupted the expression of adrenergic receptors known to participate in neurotrophic modeling of the developing brain and evoked massive induction of AC activity. As a consequence, disparate receptor inputs all produced cyclic AMP overproduction, a likely contributor to disrupted patterns of cell replication, differentiation, and apoptosis. Superimposed on the heterologous AC induction, Dex impaired specific receptor-mediated cholinergic and adrenergic signals. These results indicate that, during a critical developmental period, Dex administration leads to widespread interference with forebrain development, likely contributing to eventual, adverse neurobehavioral outcomes.  相似文献   
38.
PURPOSE: Evaluate efficacy and toxicity of bortezomib in patients with relapsed or refractory B-cell non-Hodgkin's lymphoma. PATIENTS AND METHODS: Patients were stratified, based on preclinical data, into arm A (mantle-cell lymphoma) or arm B (other B-cell lymphomas) without limitation in number of prior therapies. Bortezomib was administered as an intravenous push (1.5 mg/m2) on days 1, 4, 8, and 11 every 21 days for a maximum of six cycles. RESULTS: Sixty patients with a median number of prior therapies of 3.5 (range, one to 12 therapies) were enrolled; 33 patients were in arm A and 27 were in arm B, including 12 diffuse large B-cell lymphomas, five follicular lymphomas (FL), three transformed FLs, four small lymphocytic lymphomas (SLL), two Waldenstrom's macroglobulinemias (WM), and one marginal zone lymphoma. In arm A, 12 of 29 assessable patients responded (six complete responses [CR] and six partial responses [PR]) for an overall response rate (ORR) of 41% (95% CI, 24% to 61%), and a median time to progression not reached yet, with a median follow-up of 9.3 months (range, 1.7 to 24 months). In arm B, four of 21 assessable patients responded (one SLL patient had a CR, one FL patient had a CR unconfirmed, one diffuse large B-cell lymphoma patient had a PR, and one WM patient had a PR) for an ORR of 19% (95% CI, 5% to 42%). Grade 3 toxicity included thrombocytopenia (47%), gastrointestinal (20%), fatigue (13%), neutropenia (10%), and peripheral neuropathy (5%). Grade 4 toxicity occurred in nine patients (15%), and three deaths from progression of disease occurred within 30 days of withdrawal from study. CONCLUSION: Bortezomib showed promising activity in relapsed mantle-cell lymphoma and encouraging results in other B-cell lymphomas. Future studies will explore bortezomib in combination with other cytotoxic or biologic agents.  相似文献   
39.
40.
West Nile encephalitis emerged in 1999 in the United States, then rapidly spread through the North American continent causing severe disease in human and horses. Since then, outbreaks appeared in Europe, and in 2012, the United States experienced a new severe outbreak reporting a total of 5,387 cases of West Nile virus (WNV) disease in humans, including 243 deaths. So far, no human vaccine is available to control new WNV outbreaks and to avoid worldwide spreading. In this review, we discuss the state-of-the-art of West Nile vaccine development and the potential of a novel safe and effective approach based on recombinant live attenuated measles virus (MV) vaccine. MV vaccine is a live attenuated negative-stranded RNA virus proven as one of the safest, most stable and effective human vaccines. We previously described a vector derived from the Schwarz MV vaccine strain that stably expresses antigens from emerging arboviruses, such as dengue, West Nile or chikungunya viruses, and is strongly immunogenic in animal models, even in the presence of MV pre-existing immunity. A single administration of a recombinant MV vaccine expressing the secreted form of WNV envelope glycoprotein elicited protective immunity in mice and non-human primates as early as two weeks after immunization, indicating its potential as a human vaccine.  相似文献   
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