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Silver‐Russell syndrome (SRS) is characterized by prenatal and postnatal growth retardation with morphologic anomalies. Maternal uniparental disomy 7 has been reported in some SRS patients. PEG1/MEST is an imprinted gene on chromosome 7q32 that is expressed only from the paternal allele and is a candidate gene for SRS. To clarify its biological function and role in SRS, we screened PEG1/MEST abnormalities in 15 SRS patients from various standpoints. In the lymphocytes of SRS patients, no aberrant expression patterns of two splice variants (α and β) of PEG1/MEST were detected when they were compared with normal samples. Direct sequence analysis failed to detect any mutations in the PEG1/MEST α coding region, and there were no significant mutations in the 5′‐flanking upstream region containing the predicted promoter and the highly conserved human/mouse genomic region. Differential methylation patterns of the CpG island for PEG1/MEST α were normally maintained and resulted in the same pattern as in the normal control, suggesting that there was no loss of imprinting. These findings suggest that PEG1/MEST can be excluded as a major determinant of SRS. © 2001 Wiley‐Liss, Inc.  相似文献   
3.
Three lipopeptides, ciliatamides A-C ( 1- 3), were isolated from the deep-sea sponge Aaptos ciliata, and their structures were elucidated on the basis of spectroscopic and chemical methods. Ciliatamides A ( 1) and B ( 2) were found to be antileishmanial, while 2 also exhibited marginal cytotoxicity to HeLa cells.  相似文献   
4.
 There has been little information regarding the pharmacokinetics of antithyroid drugs in patients with endstage renal disease (ESRD). We report here the pharmacokinetics and dialyzability of the antithyroid drug thiamazole in a chronic hemodialysis patient with hyperthyroidism. The patient was a 46-year-old woman who complained of palpitations 3 years after starting chronic hemodialysis therapy, followed by several episodes of pulmonary edema. A diagnosis of hyperthyroidism due to Graves' disease was confirmed by a laboratory test for thyroid function and anti-thyroid-stimulating hormone (TSH) receptor antibodies. The plasma concentration of thiamazole was measured before and at 1, 3, 4, 5, 6, and 24 h after administration of the drug. The dialyzability of the drug was investigated during hemodialysis therapy. On the non-dialysis day, the serum half-life of thiamazole (6.4 h) was similar to that in healthy subjects (4–6 h). Further, thiamazole was removed via the dialyzer during dialysis therapy. The initial dose of thiamazole was set at 15 mg/day for the patient. Free thyroid hormone levels began to decrease 2 weeks after the initiation of thiamazole, followed by the normalization of the values after 1 month. The patient's symptoms also subsided. Several confirmations of the concentration of thiamazole in the plasma in the morning on the first dialysis day of the week did not disclose a trend of accumulation in the blood. Although this is a single case report, it is suggested that thiamazole can be used for patients with ESRD. Careful monitoring of thyroid function, however, is recommended, because the intrathyroid action of thiamazole in uremia is unknown. Received: September 20, 2001 / Accepted: May 20, 2002  相似文献   
5.
The laparoscopic approach to pancreatectomy entails a number of restrictions in performing major pancreatic surgery. This report describes a hand-assisted laparoscopic total pancreatectomy performed for a main duct intraductal papillary mucinous neoplasm of the pancreas. Dissection of the gastroduodenal artery and splenic artery, and the transection of the duodenum were done through the midline mini-laparotomy, while mobilization of the spleen and the pancreatic tail and body, and Kocher’s maneuver were performed using the hand-assisted laparoscopic approach. Furthermore, dissection of lymph nodes in the hepatoduodenal ligament, removal of the gallbladder, division of the hepatic duct, tunneling of the pancreas, and dissection of the pancreas from the superior mesenteric vein and superior mesenteric artery were possible to perform safely under a pure laparoscopic technique with an excellent laparoscopic view. The reconstruction procedures were performed through the mini-laparotomy. The hand-assisted laparoscopic total pancreatectomy should be considered for the treatment of selected patients because it has various advantages as one type of minimally invasive surgery.  相似文献   
6.
Tape-guided living donor left hepatectomy   总被引:5,自引:0,他引:5  
A procedure of tape-guided living donor left hepatectomy is described. A tape was placed along the anterior wall of the inferior vena cava for left liver with caudate lobe, and along Arantius' ligament for left liver without caudate lobe. The final step of liver transection was applied by dividing the liver parenchyma under tape guidance. This procedure contributed to safe and accurate anatomic procurement of left liver grafts in living donor hepatectomy.  相似文献   
7.
Vascular calcification (VC) is a life-threatening complication of CKD. Severe protein restriction causes a shortage of essential amino acids, and exacerbates VC in rats. Therefore, we investigated the effects of dietary l-lysine, the first-limiting amino acid of cereal grains, on VC. Male Sprague-Dawley rats at age 13 weeks were divided randomly into four groups: low-protein (LP) diet (group LP), LP diet+adenine (group Ade), LP diet+adenine+glycine (group Gly) as a control amino acid group, and LP diet+adenine+l-lysine·HCl (group Lys). At age 18 weeks, group LP had no VC, whereas groups Ade and Gly had comparable levels of severe VC. l-Lysine supplementation almost completely ameliorated VC. Physical parameters and serum creatinine, urea nitrogen, and phosphate did not differ among groups Ade, Gly, and Lys. Notably, serum calcium in group Lys was slightly but significantly higher than in groups Ade and Gly. Dietary l-lysine strongly suppressed plasma intact parathyroid hormone in adenine rats and supported a proper bone-vascular axis. The conserved orientation of the femoral apatite in group Lys also evidenced the bone-protective effects of l-lysine. Dietary l-lysine elevated plasma alanine, proline, arginine, and homoarginine but not lysine. Analyses in vitro demonstrated that alanine and proline inhibit apoptosis of cultured vascular smooth muscle cells, and that arginine and homoarginine attenuate mineral precipitations in a supersaturated calcium/phosphate solution. In conclusion, dietary supplementation of l-lysine ameliorated VC by modifying key pathways that exacerbate VC.Medial vascular calcification is common in aging, diabetes, and CKD.14 Because the presence of vascular calcification is strongly associated with increased cardiovascular morbidity and mortality, several studies in both animals and humans have sought ways to reduce the extent of vascular calcification.510 However, satisfactory therapies have not yet been established.11Adenine-induced renal failure is one of the commonly used animal models for studying the development of vascular calcification, but the prevalence of vascular calcification in this model is not very high. Indeed, Price et al. reported that vascular calcification was detected in only 30% of rats with adenine-induced chronic renal failure (adenine rats) fed a normal-protein diet.5 These authors speculated that consistent vascular calcification might require a longer period of adenine feeding. On the basis of this idea, they designed a low-protein (LP) diet in an attempt to reduce the nitrogen load and thus enable the rats to thrive on the adenine diet for longer periods. As a result of this attempt, Price et al. unexpectedly found that adenine rats fed a LP diet had extensive vascular calcification without a longer feeding period.5 All 13 adenine rats fed the LP diet had uniform alizarin red staining of the aorta, whereas only 3 of the 11 adenine rats fed a normal-protein diet had partial calcification.5 These findings indicated that dietary protein deficiency correlates with the extent of vascular calcification.Proteins are usually made from 20 kinds of amino acids. On the basis of nutritional requirements, these amino acids can be divided into two groups: essential amino acids (EAAs) and non-EAAs. Because restriction of dietary protein results in a shortage of EAAs, the level of dietary EAAs may be relevant to the extent of vascular calcification. Among nine EAAs, this study focused on l-lysine (l-Lys) based on the following three reasons. First, l-Lys is the first-limiting amino acid in most cereal grains.12 Second, the safety of l-Lys supplementation has been verified in the area of animal husbandry. l-Lys has long been added to feed grains in order to improve the utility of feed proteins.13 Third, several studies have demonstrated that dietary supplementation with l-Lys protects bones from osteoporosis, a pathologic condition that often coexists with vascular calcification.14,15 These points prompted us to hypothesize that supplementation with l-Lys would ameliorate vascular calcification. Therefore, in this study, we tested this hypothesis using adenine rats.  相似文献   
8.
BACKGROUND: Infection is a constant threat for the living-donor liver transplantation (LDLT) recipients, although little information is available on the occurrence of infection in such patients. METHODS: One hundred and thirteen consecutive LDLT recipients were prospectively followed for the presence of surgical site infections (SSIs) defined by CDC from April 2001 to March 2002. Risk factors for SSIs were evaluated by univariate and multivariate analysis. RESULTS: Of the 113 LDLT recipients, 42 (37%) developed 57 episodes of SSIs (21 intraabdominal abscess, 20 peritonitis, 8 cholangitis, and 9 wound). Of the 57 episodes, 29 (51%) had secondary bacteremia in 19 patients. Causative pathogens, including 17 episodes of polymicrobial infections, were 37 gram-positive cocci (17 Staphylococcus aureus, 16 Enterococcus spp., and 4 others), 40 gram-negative rods (25 Enterobacteriaceae, 13 Pseudomonas aeruginosa, and 4 others), and 2 Candida albicans. Univariate analysis revealed that ABO incompatibility and repeat surgery were associated with the development of SSIs. Also, univariate analysis revealed that adult recipients, ABO incompatibility, total operation duration, repeat surgery, and NNIS risk index were associated with secondary bacteremia. Multivariate analysis revealed that ABO incompatibility (OR: 14.0; 95% CI, 2.52-77.2) and repeat surgery (OR: 9.29; 95% CI, 2.00-43.1) were independently associated with secondary bacteremia. Eleven of the 42 cases (26%) who developed SSIs died. Of these 11 cases, 5 (45%) developed secondary bacteremia within 30 days before death. CONCLUSION: SSIs occurred in 37% of LDLT recipients. ABO incompatibility and repeat surgery increased the risk of developing SSIs with secondary bacteremia, which correlated with poor prognosis.  相似文献   
9.
Intraductal papillary mucinous neoplasm (IPMN) of the pancreas showed significantly less aggressive pathologic features compared with common pancreatic cancer. Therefore, several organ-preserving techniques, including duodenum-preserving pancreatic head resection, have been advocated in surgical procedures for IPMN. We describe a surgical technique of superior head resection of the pancreas with inferior branch preservation followed by a gastric wall-covering method for the prevention of pancreatic leakage in patients with IPMN of the pancreas head.  相似文献   
10.
Background/Purpose  While lipiodolized transarterial chemoembolization (lip-TACE) is effective for treating unresectable hepatocellular carcinoma (HCC), its effect for treating recurrent HCC after curative liver resection needs to be clarified. Methods  Of 163 patients who had undergone curative liver resection between 1992 and December 2003, 65 patients (39.8%) had recurrent HCC in the liver without extrahepatic recurrence and were indicated for lip-TACE. The overall survival rate after lip-TACE was calculated, and its correlation with factors such as the histology of the primary HCC and background noncancerous tissue were analyzed. Results  The overall survival rates after lip-TACE after the detection of the first recurrent HCC were 82.6%, 44.5%, and 24.8% at 1, 3, and 5 years, respectively. The factors affecting patient survival after lip-TACE were microscopic portal venous involvement of HCC at liver resection, grade of inflammation in the noncancerous liver parenchyma, and recurrence within 1 year after the initial liver resection. Multivariate analysis showed that the period between the resection and first recurrence had the highest hazard ratio. Conclusions  Lip-TACE is a reasonable procedure for treating recurrent HCC in selected patients who are not eligible for hepatic re-resection. When HCC recurred within 1 year from the primary liver resection, the effect of lip-TACE on patient survival was limited.  相似文献   
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