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701.
Briefly incubated agar cultures from positive blood cultures were used for antimicrobial susceptibility testing (AST) by Vitek 2. The cultivation time until inoculation was 3.8 h for Gram-positive cocci and 2.4 h for Gram-negative rods. The error rates were low, providing early and reliable AST without additional time or cost expenditure.  相似文献   
702.
703.
Human alpha satellite (AS) sequence domains that currently function as centromeres are typically flanked by layers of evolutionarily older AS that presumably represent the remnants of earlier primate centromeres. Studies on several human chromosomes reveal that these older AS arrays are arranged in an age gradient, with the oldest arrays farthest from the functional centromere and arrays progressively closer to the centromere being progressively younger. The organization of AS on human chromosome 21 (HC21) has not been well-characterized. We have used newly available HC21 sequence data and an HC21p YAC map to determine the size, organization, and location of the AS arrays, and compared them to AS arrays found on other chromosomes. We find that the majority of the HC21 AS sequences are present on the p-arm of the chromosome and are organized into at least five distinct isolated clusters which are distributed over a larger distance from the functional centromere than that typically seen for AS on other chromosomes. Using both phylogenetic and L1 element age estimations, we found that all of the HC21 AS clusters outside the functional centromere are of a similar relatively recent evolutionary origin. HC21 contains none of the ancient AS layers associated with early primate evolution which is present on other chromosomes, possibly due to the fact that the p-arm of HC21 and the other acrocentric chromosomes underwent substantial reorganization about 20 million years ago.  相似文献   
704.
Phagocytes generate nitric oxide (NO) and other reactive oxygen and nitrogen species in large quantities to combat infecting bacteria. Here, we report the surprising observation that in vivo survival of a notorious pathogen-Bacillus anthracis-critically depends on its own NO-synthase (bNOS) activity. Anthrax spores (Sterne strain) deficient in bNOS lose their virulence in an A/J mouse model of systemic infection and exhibit severely compromised survival when germinating within macrophages. The mechanism underlying bNOS-dependent resistance to macrophage killing relies on NO-mediated activation of bacterial catalase and suppression of the damaging Fenton reaction. Our results demonstrate that pathogenic bacteria use their own NO as a key defense against the immune oxidative burst, thereby establishing bNOS as an essential virulence factor. Thus, bNOS represents an attractive antimicrobial target for treatment of anthrax and other infectious diseases.  相似文献   
705.
Cannabis and heavy alcohol use potentially increase HIV transmission by increasing risky drug behaviors. We studied 404 subjects entering treatment for heroin dependence, in St. Petersburg, Russia. We used the HIV Risk Assessment Battery (RAB) drug subscale to measure risky drug behavior. Although all heavy alcohol users had risky drug behaviors, their drug RAB scores did not differ from non-heavy alcohol users in unadjusted or adjusted analyses. Cannabis use was significantly associated with drug RAB scores in unadjusted analyses (mean difference 1.7 points) and analyses adjusted for age, sex, and employment (mean difference 1.3 points). When also adjusting for stimulant use, the impact of cannabis use was attenuated and no longer statistically significant (mean difference 1.1 points). Because of the central role of risky drug behaviors in the Russian HIV epidemic, it is important to understand how the use of multiple substances, including cannabis and alcohol, impacts risky drug behaviors.  相似文献   
706.
Fourier transform infrared microspectroscopy (FTIR-MSP) is potentially a powerful analytical method for identifying the spectral properties of biological activity in cells. The goal of the present research is the implementation of FTIR-MSP to study early spectral changes accompanying malignant transformation of cells. As a model system, cells in culture are infected by the murine sarcoma virus (MuSV), which induces malignant transformation. The spectral measurements are taken at various postinfection time intervals. To follow up systematically the progress of the spectral changes at early stages of cell transformation, it is essential first to determine and validate consistent and significant spectral parameters (biomarkers), which can evidently discriminate between normal and cancerous cells. Early stages of cell transformation are classified by an array of spectral biomarkers utilizing cluster analysis and discriminant classification function techniques. The classifications indicate that the first spectral changes are detectable much earlier than the first morphological signs of cell transformation. Our results point out that the first spectral signs of malignant transformation are observed on the first and third day of postinfection (PI) (for NIH/3T3 and MEF cell cultures, respectively), while the first visible morphological alterations are observed only on the third and seventh day, respectively. These results strongly support the potential of developing FTIR microspectroscopy as a simple, reagent-free method for early detection of malignancy.  相似文献   
707.
Introduction: Controlling blood pressure is a global health priority; single-pill antihypertensive combinations may improve adherence, persistence, and outcomes.

Areas covered: A novel combination of perindopril arginine and amlodipine besylate was recently approved. A systematic review of the literature revealed its most common adverse effects as: peripheral edema (depending on the dose of amlodipine, but attenuated by perindopril), cough, dizziness and hypotension. Dose-dependent hyperkalemia, impairment of renal function (especially in renovascular hypertension), angioedema, and teratogenicity were derived from experience with other ACE-inhibitors.

Expert opinion: Substantial clinical trial experience with amlodipine or perindopril suggests that these two agents effectively lower blood pressure, and can reduce the risk of major adverse cardiovascular events, as in the Anglo-Scandinavian Cardiac Outcomes Trial. The incidence of adverse effects reported in clinical trials is lower than expected, likely due to exclusion of subjects previously exposed to its components; the nature of open-label, uncontrolled observational studies; and difficulty in recognizing and measuring cough and pedal edema. This new formulation of perindopril arginine protects its ethyl ester, without requiring physical separation from amlodipine in a single tablet, and is less hygroscopic than perindopril erbumine. These and other attributes may make this combination an attractive addition to the antihypertensive armamentarium.  相似文献   

708.

Background

Papillary renal cell carcinoma (PRCC) is a rare subset of RCC. The Cancer Genome Atlas (TCGA) data largely reflect localized disease, and there are limited data for advanced PRCC.

Objective

To characterize the frequency of genomic alterations (GAs) in patients with advanced PRCC for whom comprehensive genomic profiling (CGP) was performed in the context of routine clinical care.

Design, setting, and participants

Formalin-fixed, paraffin-embedded tissue was obtained for 169 consecutive patients with confirmed PRCC. DNA was extracted and comprehensive genomic profiling was performed in a certified central laboratory.

Measurements

Hybrid-capture, adaptor ligation-based libraries of up to 315 genes were sequenced to a median coverage of 648×. All classes of GAs were identified, including substitutions, insertions/deletions, copy number alterations, and rearrangements.

Results and limitations

From 169 patients, either primary tumor tissue (102 patients, 60%) or metastatic tissue (67 patients, 40%) was collected. In patients with type 1 PRCC, commonly altered genes were MET (33%; 8 activating mutations, 5 amplifications at > 6 copies), TERT (30%), CDKN2A/B (13%), and EGFR (8%). In patients with type 2 PRCC, commonly altered genes were CDKN2A/B (18%), TERT (18%), NF2 (13%), and FH (13%); MET GAs (5 mutations, 3 amplifications) were observed in 7% of type 2 cases. Notable differences from TCGA data include higher frequencies of MET, NF2, and CDKN2A/B GAs, association of alterations in SWI/SNF complex genes with type 2 PRCC, and observation of frequent CDKN2A/B alterations in both type 1 and type 2 disease.

Conclusions

Both the current study and the TCGA experience represent similarly sized cohorts of patients with PRCC. Key differences in GA frequency probably underscore the marked difference in stage distribution between these data sets. These results may inform planned precision medicine trials for metastatic PRCC.

Patient summary

Papillary renal cell carcinoma (PRCC) is a rare subtype of kidney cancer, and understanding of the biology of advanced PRCC is limited. This report highlights some of the unique biologic features of PRCC that may inform on future use of targeted therapies for the treatment of metastatic disease.  相似文献   
709.
AIM:To determine the effectiveness of using multidetector computed tomography(MDCT)data in preoperative planning of robot-assisted surgery.METHODS:Fourteen patients indicated for surgery underwent MDCT using 64 and 256-slice MDCT.Before the examination,a specially constructed navigation net was placed on the patient’s anterior abdominal wall.Processing of MDCT data was performed on a Brilliance Workspace 4(Philips).Virtual vectors that imitate robotic and assistant ports were placed on the anterior abdominal wall of the 3D model of the patient,considering the individual anatomy of the patient and the technical capabilities of robotic arms.Sites for location of the ports were directed by projection on the roentgen-positive tags of the navigation net.RESULTS:There were no complications observed during surgery or in the post-operative period.We were able to reduce robotic arm interference during surgery.The surgical area was optimal for robotic and assistant manipulators without any need for reinstallation of the trocars.CONCLUSION:This method allows modeling of the main steps in robot-assisted intervention,optimizing operation of the manipulator and lowering the risk of injuries to internal organs.  相似文献   
710.
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