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51.

Background

Biliary atresia (BA) is a cholestatic disease of unknown etiology. It has recently been suggested that graft-vs-host disease caused by microchimerism is an etiology in the development of autoimmune disease. Moreover, the liver is a frequent target organ of graft-vs-host disease. The aim of this study is to identify the presence and extent of maternal microchimerism and to determine whether it plays a role in the etiology of BA.

Methods

The liver biopsy specimens of 6 male patients with BA (BA group) and 6 males with other liver diseases (non-BA group) were assayed for X- and Y-chromosome using fluorescent in situ hybridization. The cells with 2 sex chromosomes in the nuclei were counted. Cells with 1 X- and 1 Y-chromosomes were considered to be host cells, and those with 2 X-chromosome were considered to be of maternal origin.

Results

The frequency of cells with XX chromosomes per 1000 host cells in the BA group and the non-BA group were 3.00 ± 0.75 and 0.99 ± 0.50, respectively (P = .005). Moreover, the age at the time of biopsy did not affect the number of chimeric cells.

Conclusion

The presence of female cells in the liver of male patients with BA was significantly higher than in males with other liver disease. Maternal microchimerism is therefore suggested to contribute to the pathogenesis of BA.  相似文献   
52.
BACKGROUND: Clonidine can effectively reduce pain and/or hypersensitivity. However, the antihypersensitivity effects of clonidine topically applied in cream (CC) have not been investigated. The authors evaluated effects of topical application of CC on pain behaviors and spinal Fos-like immunoreactivity in rats with hypersensitivity. METHODS: Clonidine (30, 100, and 300 microg/g) was prepared in a cream base. In rat models of neuropathic pain, inflammatory pain, and postoperative pain, the authors evaluated effects of CC (0.1 g), topically applied onto the plantar surface of the injured or uninjured paw, on thermal hyperalgesia and mechanical allodynia to von Frey filaments. The authors also evaluated effects of CC on lumbar spinal Fos-like immunoreactivity. RESULTS: In neuropathic rats, CC applied onto the injured paw reduced thermal hyperalgesia and mechanical allodynia dose dependently, whereas CC applied onto the uninjured paw had no effect. The antihypersensitivity effects of CC were antagonized by intraperitoneal yohimbine (10 mg/kg). Further, CC reduced Fos-like immunoreactivity in neuropathic rats. In contrast, CC in a single dose had no effects on hyperalgesia, allodynia, or Fos-like immunoreactivity in rats with inflammatory or postoperative pain. In rats with postoperative pain, CC repeatedly applied for 6 days reduced thermal hyperalgesia, but not mechanical allodynia, in the postoperative days, whereas it had no effects on hyperalgesia or allodynia in those with inflammatory pain. CONCLUSIONS: Topical CC in concentrations examined significantly reduced hypersensitivity and lumbar spinal Fos-like immunoreactivity in rats with neuropathic pain, probably through activation of peripherally located alpha2 adrenoceptors. However, CC was only partially effective and totally ineffective in rats with postoperative pain and inflammatory pain, respectively.  相似文献   
53.
Background. Vascular calcification is an independent determinantof cardiovascular events in maintenance haemodialysis (HD) patients.It is not known whether acute changes of the serum calcium concentrationbefore and after HD (Ca) are associated with the developmentof aortic calcification. Methods. We enrolled 71 patients dialysed with a dialysate with3.0 mEq/l calcium and determined their aortic calcificationindex (ACI) by abdominal computed tomography twice at an intervalof 3 years. To identify the factors contributing to the rateof progression of aortic calcification, we analysed the averagevalues for clinical and laboratory data obtained between thefirst and second evaluations of ACI. Results. The second ACI (mean ± SD: 80.2 ± 63.9)was significantly greater than the first ACI (61.0 ±61.0) after an interval of 35.8 ± 4.2 months. The annualizedchange of ACI (ACI/year) was significantly and directly associatedwith the Ca and C-reactive protein (CRP) (both P < 0.001,P for trend). Stepwise multivariate regression analysis revealedthat ACI/year was positively and independently associated withCRP, presence of diabetes mellitus and Ca, but negatively associatedwith a premenopausal status in women. Similarly, Ca was positivelyand independently associated with ACI/year and the ultrafiltrationrate, but was negatively associated with pre-HD Ca. Conclusion. The increase of serum calcium after HD was relatedto the rate of progression of aortic calcification. Excess calciumis transferred into patients on HD when using a dialysate of3.0 mEq/l calcium. This may be a risk factor for the developmentof vascular calcification.  相似文献   
54.
Background: Clonidine can effectively reduce pain and/or hypersensitivity. However, the antihypersensitivity effects of clonidine topically applied in cream (CC) have not been investigated. The authors evaluated effects of topical application of CC on pain behaviors and spinal Fos-like immunoreactivity in rats with hypersensitivity.

Methods: Clonidine (30, 100, and 300 [mu]g/g) was prepared in a cream base. In rat models of neuropathic pain, inflammatory pain, and postoperative pain, the authors evaluated effects of CC (0.1 g), topically applied onto the plantar surface of the injured or uninjured paw, on thermal hyperalgesia and mechanical allodynia to von Frey filaments. The authors also evaluated effects of CC on lumbar spinal Fos-like immunoreactivity.

Results: In neuropathic rats, CC applied onto the injured paw reduced thermal hyperalgesia and mechanical allodynia dose dependently, whereas CC applied onto the uninjured paw had no effect. The antihypersensitivity effects of CC were antagonized by intraperitoneal yohimbine (10 mg/kg). Further, CC reduced Fos-like immunoreactivity in neuropathic rats. In contrast, CC in a single dose had no effects on hyperalgesia, allodynia, or Fos-like immunoreactivity in rats with inflammatory or postoperative pain. In rats with postoperative pain, CC repeatedly applied for 6 days reduced thermal hyperalgesia, but not mechanical allodynia, in the postoperative days, whereas it had no effects on hyperalgesia or allodynia in those with inflammatory pain.  相似文献   

55.
Laparoscopic spleen-preserving distal pancreatectomy (LSDP) with conservation of the splenic vessels is gaining acceptance as a reliable treatment for selected patients with low-grade malignant tumors of the pancreas in adults. The operation requires advanced laparoscopic skills to safely divide the fine branches of the splenic vessels. Laparoscopic spleen-preserving distal pancreatectomy with conservation of splenic vessels is rarely reported in children. We describe a 12-year-old girl with solid pseudopapillary tumor in the body of the pancreas that was successfully treated with LSDP, preserving the splenic vessels. The postoperative course was uneventful, and the functional and aesthetic results were satisfactory. Laparoscopic spleen-preserving distal pancreatectomy with conservation of splenic vessels may be a safe and feasible treatment option for children with pancreatic disease.  相似文献   
56.

Background  

Chronic kidney disease (CKD) is a health-related quality-of-life (HRQOL) deteriorating disease which is not only a public health but also a socioeconomic problem. Interest in developing cost-effective interventions to control CKD has increased. The aim of this study was to measure HRQOL in terms of quality-adjustment weights for cost-effectiveness analysis using EQ-5D in patients with CKD. The relationships between the measured HRQOL and clinical indices/complications were also analyzed.  相似文献   
57.
Liposome‐encapsulated hemoglobin (LEH) is protective early after brain ischemia in rats and nonhuman primates, but it remains unclear whether the protection persists and confers any benefits beyond the acute phase of brain ischemia and reperfusion. Ten monkeys underwent middle cerebral artery occlusion, received LEH (2 mL/kg, n = 5) or saline (2 mL/kg, n = 5) 5 min later, and reperfusion 3 h later. Positron emission tomography studies were repeated for the cerebral metabolic rate of O2 (CMRO2) as well as glucose (CMRglc) up to 8 days after reperfusion, when the animals were euthanized for morphological studies. There was no difference in O2 metabolism until 3 h after reperfusion, when CMRO2 was significantly better preserved in the cortex, but not in basal ganglia, on Day 0 in LEH‐treated monkeys. The extent of cortical infarction (saline 68 ± 10% vs. LEH 38 ± 9%, P < 0.05) and CMRO2 (mild suppression: saline 34 ± 10% vs. LEH 14 ± 4%, P < 0.05) remained significantly better preserved 8 days later, when CMRglc showed a similar pattern of cortical protection (mild suppression: saline 49 ± 15% vs. LEH 37 ± 4%, P < 0.05) in LEH‐treated monkeys, together with regained body weight. Somatic weight control, morphological integrity, CMRO2, and CMRglc were better preserved immediately, as well as 8 days after occlusion and reperfusion of the middle cerebral artery in monkeys receiving LEH early after onset of ischemia.  相似文献   
58.
59.
PURPOSE: To evaluate the long-term effect of vitrectomy with or without arteriovenous sheathotomy for macular edema secondary to branch retinal vein occlusion (BRVO). METHODS: The study was a prospective, randomized, comparative, interventional case series of 36 patients (36 eyes) who underwent pars plana vitrectomy with or without arteriovenous sheathotomy for macular edema due to BRVO of 相似文献   
60.
Gastrinoma is a rare endocrine tumor that is frequently associated with liver metastasis. The liver metastasis is usually seen simultaneously or soon after a primary operation. A 47-year-old woman who had had a total gastrectomy 20 years earlier developed liver metastasis. An interval of this length between surgery and metastasis is extremely rare. The total gastrectomy prevented the patient from developing the usual symptoms of hypergastrinemia that would have enabled early diagnosis of the metastasis. Laboratory examinations on admission revealed a high serum gastrin concentration (1500 pg/ml). Computed tomography showed an irregularly enhanced mass lesion with an uneven, low-density central area in the right anterior inferior segment of the liver. An extended right hepatectomy was performed. Intraoperative ultrasonography showed no abnormalities in the remnant pancreas. Examination of the cut surface of the specimen revealed a yellow, firm, elastic tumor, 55 mm in diameter. The interior of the tumor appeared necrotic. Histopathologically, the tumor was composed of cells with hyperchromatic, dysplastic nuclei arranged in a trabecular pattern with nest formation. Gastrin staining was positive. A histologic diagnosis of metastatic gastrinoma was made. The patient's gastrin concentration returned to normal and she was well at 2-year follow-up. Received: August 19, 1999 / Accepted: January 28, 2000  相似文献   
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