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We found earlier that NAPA represents an anti-apoptotic protein that promotes resistance to cisplatin in cancer cells by inducing the degradation of the tumor suppressor p53. In the present study, we investigated the cellular mechanism underlying the degradation of p53 by NAPA. Knockdown of NAPA using short-hairpin RNA was shown to induce p53 accumulation and to sensitize HEK293 cells to cisplatin. On the other hand, this sensitization effect was not found in H1299 lung carcinoma cells which lack p53. Expression of exogenous p53 in H1299 cells was increased following knockdown of NAPA and these cells showed increased sensitivity to cisplatin-induced apoptosis. Notably, knockdown of NAPA induced the ubiquitination and degradation of the E3 ubiquitin ligase synoviolin and the accumulation of p53 in unstressed HEK293 cells. Conversely, NAPA overexpression decreased the ubiquitination and degradation of synoviolin, and reduced p53 protein level. Knockdown of NAPA disrupted the interaction between synoviolin and proteins that form the endoplasmic reticulum-associated degradation (ERAD) complex and in turn decreased the ability of this complex to ubiquitinate p53. In addition, knockdown of NAPA induced the activation of the MAPK kinases ERK, JNK and p38, but only inhibition of ERK reduced synoviolin ubiquitination and p53 accumulation. These results indicate that NAPA promotes resistance to cisplatin through synoviolin and the ERAD complex which together induce the degradation of p53 and thus prevent apoptosis. Based on these findings, we propose that the combination of cisplatin and knockdown of NAPA represents a novel and attractive strategy to eradicate p53-sensitive cancer cells.  相似文献   
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The present study investigated the effects of a Neurologic Music Therapy (NMT) sensory-motor rehabilitation technique, Therapeutic Instrumental Music Performance (TIMP) as compared to Traditional Occupational Therapy (TOT), on endurance, self-perceived fatigue, and self-perceived exertion of 35 hospitalized patients in physical rehabilitation. The present study attempted to examine whether an active musical experience such as TIMP with musical cueing (i.e., rhythmic auditory cueing) during physical exercises influences one's perception of pain, fatigue, and exertion. All participants were diagnosed with a neurologic disorder or had recently undergone orthopedic surgery. Investigators measured the effects of TOT and TIMP during upper extremity exercise of the less affected or stronger upper extremity. Results showed no significant difference on endurance measures between the 2 treatment conditions (TIMP and TOT). Statistically significant differences were found between TIMP and TOT when measuring their effects on perceived exertion and perceived fatigue. TIMP resulted in significantly less perception of fatigue and exertion levels than TOT. TIMP can be used foran effective sensory-motor rehabilitation technique to decrease perceived exertion and fatigue level of inpatients in physical rehabilitation.  相似文献   
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Efficient control of cell survival and cell proliferation is critical for the development of neuron cells. Earlier, we observed that growth arrest-specific gene 7 (Gas7) plays a role in controlling neuritogenesis in mammals. In the present study, we report that the Gas7b isoform is involved in controlling growth arrest and apoptosis of neuroblastoma cells in response to various stimuli. Accordingly, knockdown of Gas7b using small-hairpin RNA (shRNA) was shown to reduce apoptosis induced either by serum starvation or by the antineoplastic agents cisplatin and nocodazole in human neuroblastoma SH-SY5Y cells. Gas7b knockdown also enhanced the ability of the treated cells to form clones in response to cisplatin. On the other hand, forced expression of Gas7a or Gas7b isoform in mouse neuroblastoma Neuro2A cells, which express a defective Gas7 gene, rendered the cells proapoptotic and vulnerable to cisplatin-induced apoptosis. In addition, Neuro2A cells that overexpressed Gas7 showed a reduced ability to form clones. Overexpression of Gas7 produced similar but less extensive effects in nonneuronal HEK293 cells. Taken together, our observations suggest that Gas7b is involved not only in neuritogenesis but also in the regulation of neuronal cell death.  相似文献   
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Introduction

There are three different pneumococcal vaccines available for infants, each oriented to a specific set of serotypes. The vaccination of newborns will prevent pneumococcal disease in this vaccinated group via direct effects, and will also affect the non-vaccinated population through indirect or “herd” immunity.

Objective

To develop a model that compares the health and economic consequences between the three vaccines.

Method

We developed a simulation model for an entire population, providing vaccine to children less than 2 years of age. The vaccines varied by serotypes covered and included a 7- (4, 6B, 9V, 14, 18C, 19F and 23F), 10- (1, 4, 5, 6B, 7F, 9V, 14, 18C, 19F and 23F) and 13-valent (1, 3, 4, 5, 6A, 6B, 7F, 9V, 14, 18C, 19A, 19F and 23F) vaccines. The base case was PCV-7, and clinical and economic outcomes were estimated for the vaccinated persons and for other persons through assumptions about a herd effect. By comparison, clinical and economic outcomes for the population were also estimated for the 10 and 13 serotype vaccines.

Results

In the base case (PCV-7), with the seven serotype vaccine, there were 9.38 cases of hospitalized pneumonia, 0.22 cases of meningitis, 3.69 cases of bacteremia, 60.19 cases of otitis media, and 373 cases of pneumonia, per 100,000 persons in the population, at all ages. With the 10-valent vaccine and a herd effect, invasive pneumonia fell to 8.71 cases, meningitis to 0.21 cases, and bacteremia to 3.39 cases. Otitis media fell to 57 cases and pneumonia to 344 cases. There were further reductions with the 13-valent vaccine, with invasive pneumonia falling to 8.37 cases, bacteremia to 3.33 cases, otitis media to 51.9 cases and all-cause pneumonia to 336.2 cases. Among the vaccines evaluated, PCV-13 was associated with the lowest health services costs and the greatest improved health outcomes.

Conclusions

Increased serotype coverage of the 13-valent vaccine is expected to have a substantial public health and economic impact on infectious disease, when considering direct and indirect effects.  相似文献   
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