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Drug resistance—arising from the misuse and overuse of antimicrobial agents—is becoming a major concern as new strains of resistant microorganisms are emerging and fewer new antimicrobial drugs are in development. This paper presents an idea of implementing a Real Time Web Based Information System to monitor changes in the antibiotic sensitivity of microorganisms, located at different areas and time periods based on data collected from accredited laboratories. This pattern can be mapped over geographical map of the area and can be interpreted by clinicians/policy makers. The authors demonstrate the use of such information system using cross sectional data obtained from a nasopharyngeal swab survey of 151 children affected with HIV. Such system can aid physicians to improve the choice of antibiotic to be administered using real time data.  相似文献   
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Background

MCPH1 is a proximal regulator of DNA damage response pathway that is involved in recruitment of phosphorylated ATM to double-stranded DNA breaks.

Methods

To understand the importance of MCPH1 and ATM in deregulation of DNA damage response pathway in breast carcinoma, we studied m-RNA expression and genetic/epigenetic alterations of these genes in primary breast carcinoma samples.

Results

Our study revealed reduced expression (mRNA/protein) and high alterations (deletion/methylation) (96 %, 121 of 126) of MCPH1 and ATM. Mutation was, however, rare in inactivation of MCPH1. In immunohistochemical analysis, reduced protein expression of MCPH1, ATM and p-ATM were concordant with their molecular alterations (P = 0.03–0.01). Alterations of MCPH1 and deletion of ATM were significantly high in estrogen/progesterone receptor–negative than estrogen/progesterone receptor–positive breast carcinoma samples compared to early or late age of onset tumors, indicating differences in pathogenesis of the molecular subtypes (P = 0.004–0.01). These genes also showed differential association with tumor stage, grade and lymph node status in different subtypes of breast carcinoma (P = 0.00001–0.01). Their coalterations showed significant association with tumor progression and prognosis (P = 0.003–0.05). Interestingly, patients with alterations of these genes or MCPH1 alone had poor outcome after treatment with DNA-interacting drugs and/or radiation (P = 0.01–0.05).

Conclusions

Inactivation of MCPH1-ATM-associated DNA damage response pathway might have an important role in the development of breast carcinoma with diagnostic, prognostic and therapeutic implications.

  相似文献   
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Synaptobrevins or VAMPs are vesicle-associated membrane proteins, often called v-SNARES, that are important for vesicle transport and fusion at the plasma membrane. Drosophila has two characterized members of this gene family: synaptobrevin (syb) and neuronal synaptobrevin (n-syb). Mutant phenotypes and gene-expression patterns indicate that n-Syb is exclusively neuronal and required only for synaptic vesicle secretion, whereas Syb is ubiquitous and, as shown here, essential for cell viability. When the eye precursor cells were made homozygous for syb(-), the eye failed to develop. In contrast, n-syb(-) eye clones developed appropriately but failed to activate downstream neurons. To determine whether the two proteins are structurally specialized to accomplish these distinct in vivo functions, we have driven the expression of each gene in the absence of the other to look for phenotypic rescue. We find that expression of n-syb during eye development can rescue the cell lethality of the syb mutations, as can rat VAMP2 and cellubrevin. Expression of syb can restore synaptic transmission to n-syb mutants as assayed both by electroretinogram and recordings of excitatory junctional currents at the neuromuscular junction. Therefore, we find that Syb, which usually is not involved in synaptic function, can mediate Ca(2+)-triggered synaptic activity and that no particular specialization of the v-SNARE is required to differentiate synaptic exocytosis from other forms.  相似文献   
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