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BACKGROUND: The A to C transversion in the promoter region of the gene encoding leukotriene C4 synthase (LTC4S) is proposed to be associated with the development of aspirin-induced asthma (AIA). OBJECTIVE: We investigated the frequency of the polymorphism in Japanese population and its association with clinical characteristics and cysteinyl leukotriene production. METHODS: Genotyping of LTC4S gene promoter was performed on 60 patients with AIA, 100 patients with aspirin-tolerant asthma (ATA), and 110 control subjects. We assessed the basal levels of urinary LTE4, the increment of urinary LTE4 on venous aspirin challenge, and LTC4S activity in peripheral blood eosinophils. RESULTS: The frequency of the variant C allele was significantly higher in patients with AIA (frequency of allele [q] = 0.192) than in patients with ATA (q = 0.110, P =.042). Variant C-allelic carriers experienced asthma at a significantly younger age (31.8 +/- 2.9 years [mean +/- SEM]) than wild-type A homozygotes (41.3 +/- 2.2 years, P =.007). Basal levels of LTE4 and the increment of urinary LTE4 on venous aspirin challenge did not show a difference between wild-type A homozygotes and variant C-allelic carriers. There was no relationship between the polymorphism and the LTC4S activity in eosinophils, although LTC4S activities were significantly higher in patients with AIA than in patients with ATA. CONCLUSION: Our findings reveal the lack of functionality of the polymorphism in the LTC4S gene, whereas this polymorphism might have some effect on the development of AIA, probably in linkage disequilibrium with another causatively important mutation.  相似文献   
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Clinicopathological data on seven instances of primary intestinal myopathy in children are reported. The ages of the patients ranged from eleven months to thirteen years. A persistent intestinal obstruction was the main and constant clinical feature. An ineffective intestinal propulsion was documented on manometric studies. Various urological abnormalities were present in three cases. One patient died and six survive but are dependent on enteral and parenteral nutrition. The morphological findings consisted of degenerative changes involving the muscular layers of the intestinal wall. These changes varied from cytoplasmic vacuolation to definite atrophy and disappearance of the muscular fibers. An extensive interstitial fibrosis underlined these atrophic changes in the late stages of the disease. A familial history was identified in three cases, one consistent with an autosomal dominant transmission.  相似文献   
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We report a case of intermittent complete left bundle branch block (CLBBB) which occurred during general anesthesia. An 83-year-old female was scheduled for upper lobectomy of the right lung under general anesthesia. Her preoperative 12-lead ECG showed atrial fibrillation and ST-depression in V4-6. Anesthesia was induced with propofol and pentazocine, and maintained with 0.5-1.5% isoflurane, 0-50% nitrous oxide in oxygen under close monitoring and appropriate respiratory management. The operation was performed uneventfully. Several minutes after the end of surgery, on converting her into the supine position from the left lateral decubitus position, widened QRS complexes, later diagnosed as CLBBB, appeared on ECG. At that time, heart rate was 92 beats x min(-1). After the administration of esmolol hydrochloride, heart rate decreased rapidly in a few minutes and ECG returned to normal conduction from CLBBB. We diagnosed this as rate-dependent intermittent CLBBB. Although intermittent CLBBB continued until the next day, the patient was asymptomatic and cardiac enzymes were within normal ranges. The intermittent CLBBB, which occasionally occurs during anesthesia, makes the diagnosis of myocardial ischemia and acute myocardial infarction difficult. The present case suggests that esmolol can be used effectively and safely to distinguish CLBBB as a benign disorder from myocardial ischemia in a patient with CLBBB.  相似文献   
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Purpose

Image-guided surgery (IGS) for otological procedures requires minimal invasiveness and a high degree of accuracy. We have recently developed a noninvasive registration method, the Surface Template-Assisted Marker Positioning (STAMP) method, which uses a rigid template of the surface of the temporal bone. However, the STAMP method is not applicable when the bony surface is not exposed, such as in endoscopic surgery. Thus, we extended our research to apply the STAMP method onto the skin and tested its feasibility in this study.

Methods

We designed a phantom made of a rigid box and soft material for the study. The target registration error (TRE) was measured at preset measuring points in the phantom. We modified the STAMP method to be applicable for use on the skin around the ears (S-STAMP). The same phantom was also registered using the conventional, manually scanned surface matching method. We compared the TRE after the different registration methods.

Results

The TRE after the S-STAMP registration method was significantly smaller than that of the conventional surface matching method at all error measurement points in the phantom. However, the TRE after the S-STAMP registration method was significantly larger than that of paired point registration using invasive fiducial markers.

Conclusions

The S-STAMP method using a rigid template on the soft surface yields a significantly smaller TRE than that of conventional, manually scanned surface matching registration. This strategy provides an alternative option to improve the accuracy of IGS without loading patients with additional invasive procedures.
  相似文献   
1000.
HIV-1 infection is often complicated by the dysfunction of central nervous system (CNS). Degenerative neuronal changes as well as neuronal loss have been documented in individuals with acquired immunodeficiency syndrome. Feline immunodeficiency virus (FIV) causes similar CNS manifestation and FIV infected cats provide an animal model for human immunodeficiency virus infection in humans. In this study, we examined the brain of FIV-infected cats and controls with immunohistochemical techniques using antibodies to microtubule-associated protein 2 (MAP-2) and glutamic acid decarboxylase (GAD). We found a significant decrease in expression of MAP-2 and GAD in neurons of infected animals compared to controls. In contrast, the expression of neurofilaments and glial fibrillary acidic protein was rather increased. The changes observed in the brain were similar to those seen in humans undergoing the normal aging process as well as those suffering from neurological diseases like Alzheimer's disease and other dementing disorders. These changes in the feline brain give insight into the deleterious effects of FIV on the CNS.  相似文献   
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