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1.
The progress of modern medicine would be impossible without the use of general anesthetics (GAs). Despite advancements in refining anesthesia approaches, the effects of GAs are not fully reversible upon GA withdrawal. Neurocognitive deficiencies attributed to GA exposure may persist in neonates or endure for weeks to years in the elderly. Human studies on the mechanisms of the long-term adverse effects of GAs are needed to improve the safety of general anesthesia but they are hampered not only by ethical limitations specific to human research, but also by a lack of specific biological markers that can be used in human studies to safely and objectively study such effects. The latter can primarily be attributed to an insufficient understanding of the full range of the biological effects induced by GAs and the molecular mechanisms mediating such effects even in rodents, which are far more extensively studied than any other species. Our most recent experimental findings in rodents suggest that GAs may adversely affect many more people than is currently anticipated. Specifically, we have shown that anesthesia with the commonly used GA sevoflurane induces in exposed animals not only neuroendocrine abnormalities (somatic effects), but also epigenetic reprogramming of germ cells (germ cell effects). The latter may pass the neurobehavioral effects of parental sevoflurane exposure to the offspring, who may be affected even at levels of anesthesia that are not harmful to the exposed parents. The large number of patients who require general anesthesia, the even larger number of their future unexposed offspring whose health may be affected, and a growing number of neurodevelopmental disorders of unknown etiology underscore the translational importance of investigating the intergenerational effects of GAs. In this mini review, we discuss emerging experimental findings on neuroendocrine, epigenetic, and intergenerational effects of GAs.  相似文献   
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Objective

Hypertonic saline (HTS) has potent immune and vascular effects. We assessed recipient pretreatment with HTS on allograft function in a porcine model of heart transplantation and hypothesized that HTS infusion would limit endothelial and left ventricular (LV) dysfunction following transplantation.

Methods

Heart transplants were performed after 6 hours of cold ischemic storage. Recipient pigs were randomized to treatment with or without HTS (7.5% NaCl) before cardiopulmonary bypass (CPB). Using a myograft apparatus, coronary artery endothelial-dependent (Edep) and -independent (Eind) relaxation was assessed. LV performance was determined using pressure-volume loop analysis. Pulmonary interleukin (IL)-2, IL-6, and tumor necrosis factor (TNF)-α expression was measured.

Results

Weaning from CPB and LV performance after transplantation were improved in HTS-treated animals. Successful weaning from CPB was greater in the HTS-treated hearts (8 of 8 vs 2 of 8; P < .05). Mean LV functional recovery was improved in the HTS-treated animals, as assessed by preload recruitable stroke work (65 ± 10% vs 27 ± 10%; P < .001) and end-systolic elastance (55 ± 7% vs 37 ± 4%; P < .001). Treatment with HTS resulted in improved Edep (mean maximum elastance [Emax], 56 ± 5% vs 37 ± 7%; P < .001) and Eind (mean Emax%, 77 ± 6% vs 52 ± 4%; P < .001) vasorelaxation compared with control. Pulmonary expression of IL-2, IL-6, and TNF-α increased following transplantation, whereas HTS therapy attenuated IL production (P < .001). Transplantation increased plasma TNF-α levels and LV TNF-α expression, whereas HTS prevented this up-regulation (P < .001).

Conclusions

Recipient HTS pretreatment preserves allograft vasomotor and LV function, and HTS therapy limits CPB-induced injury. HTS may be a novel recipient intervention to prevent graft dysfunction.  相似文献   
4.
Functional recovery, the goal of treatment, has long been overlooked in the assessment of effectiveness of pharmacological treatments. However, with the recent shift in paradigm, from syndromal–symptomatic recovery to functional recovery, there appears to be a new interest in the definition and evaluation of functional recovery. Since functional recovery lags symptomatic recovery, sometimes by months or years, the attainment of functional recovery will be determined by both efficacy and long-term compliance. Quetiapine, due to its efficacy in both mania and depression, and effect on cognition may lead to improved functioning in patients with bipolar disorder.  相似文献   
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Congenital thoracic ectopic kidney is a very rare developmental anomaly and the rarest form of all ectopic kidneys. It is usually asymptomatic and discovered incidentally on routine chest radiography. Herein we reported the first case of staghorn stone in a thoracic kidney managed successfully by percutaneous nephrolithotomy.  相似文献   
7.
Which patient, which pump?   总被引:1,自引:0,他引:1  
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8.
X-ray fluorescence analysis has been used for measurement of lead in paint for more than a decade. The early systems provided a nondestructive alternative technology to laboratory-based technologies, but were somewhat time consuming and often led to inconclusive results. The procedure required manual substrate correction, multiple measurements, operator's discretion in validating a measurement due to interfering elements and laboratory analysis of inconclusive samples. A new instrument, the RMD LPA-1 system, has been developed based on X-ray fluorescence technology that addresses all of the drawbacks to the older systems. This new system uses a carefully designed and controlled geometry and modern microprocessor technology to automatically provide a rapid quantitative measurement of lead in paint with a 95% confidence level. The improved precision and accuracy achieved with this system are due to geometric enhancements and a mathematical approach which incorporates corrections for both random and systematic errors such as matrix effects and Compton scatter. This technology has been incorporated in a hand-held X-ray fluorescence lead paint analyzer system. A key design philosophy for this system was to maintain a very narrow, task-specific focus, the system was not designed to be an all purpose XRF analyzer, rather it is optimized to meet regulatory requirements of lead paint testing in the most efficient manner. The development of the LPA-1 system is an example of what can be accomplished by listening to the needs and desires of the users, rethinking the design of an existing technique and incorporating modern microprocessor technology.  相似文献   
9.
The sensitivity of non-isotopic in situ hybridization (NISH), particularly on formalin-fixed, paraffin-embedded (FFPE) clinical tissues, has been the subject of controversy. Generally, NISH has been regarded as being less sensitive than radiolabelled procedures, although some reports have contradicted this. Accordingly, tissues from mice which were transgenic for variable amounts of the human alpha-1-antitrypsin gene were used to optimize the NISH procedure and to estimate the sensitivity. This approach showed that prolonged incubation of slides in final substrate resulted in high sensitivity--about 13 kb of target DNA. However, this prolonged incubation crucially depended on achieving minimal non-specific background staining. Many factors affected the degree of background staining, but five were particularly important. First, the method of mounting cut sections onto slides. Second, the length of the probe (ideally less than 400 bp). Third, the procedure for proteolytic digestion. Fourth, the denaturation technique, and fifth, the quality of the dextran sulphate used in the hybridization mix. The optimized protocol showed variable patterns of mRNA distribution in the transgenic mouse livers, while DNA distribution appeared uniform.  相似文献   
10.
Gangrene of Meckel's diverticulum is uncommon and its pre-operative diagnosis is difficult. We report three cases with different presentations--simulating acute appendicitis, intestinal obstruction, and strangulation of the bowel.  相似文献   
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