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101.
We developed a new technique of aortic root repair which may be able to eliminate the potential problem of leaflet damage, resulting from the direct contact of the aortic leaflets with synthetic vascular grafts during systole. This report describes our technique of annuloaortic repair and the operative results. Between February 1995 and October 1998, 13 patients underwent annuloaortic repair. The patients included 8 males and 5 females (mean age 50 years). Four patients had grade IV/IV aortic regurgitation (AR), 5 had III/IV AR, 2 had II/IV AR, and 1 had no AR preoperatively. Regarding the preoperative functional status, 1 patient was classified as New York Heart Association class IV, 5 were class III, 6 class II, and 1 class I. Concomitant cardiovascular procedures were performed in 12 cases. Aortic valvuloplasty or annuloplasty was performed in 7 patients. Both operative and short-term postoperative results with pre- and postoperative echocardiographic findings were studied retrospectively. The mean total cardiopulmonary bypass time was 212 min. The mean aortic cross-clamp time was 130 min. Circulatory arrest was induced in 5 patients. Postoperatively, 7 patients had no AR. Three patients had grade I/IV AR and 3 had grade II/IV AR. Perioperative changes in aortic annulus, mid-sinus portion, and sinotubular junction diameters were determined echocardiographically in 5 patients. The preoperative diameters were 2.7 +/- 0.4, 5.4 +/- 0.5, and 4.7 +/- 1.0 cm, respectively. The postoperative diameters were 2.3 +/- 0.5, 4.2 +/- 0.5, and 3.5 +/- 0.5cm, respectively. Ten patients were class I and 2 were class II. This technique of annuloaortic repair with or without aortic valvuloplasty is applicable to a certain subset of patients with aortic root disease and AR. Both the indications for this procedure and the long-term results should be confirmed.  相似文献   
102.
Abstract:  Tuberculosis remains one of the most serious infections after organ transplantation. Isoniazid prophylaxis for liver transplant recipients with a history of tuberculosis is generally recommended. However, its benefit is controversial because of potential hepatotoxicity of isoniazid. It is crucial to determine appropriate post-transplant managements for the recipients with a history of tuberculosis. The purpose of this study was to investigate the necessity of isoniazid prophylaxis for liver transplant recipients who had a history of tuberculosis. The medical records of 1116 liver transplant recipients were studied, of whom seven had a history of tuberculosis (0.63%). One who underwent living-donor liver transplantation for fulminant hepatic failure was excluded from evaluation because of early death, caused by bacterial sepsis two months after transplantation, although reactivation of tuberculosis was not observed. The median observation period after transplantation was 25.5 months (range 12–82). Reactivation of tuberculosis did not occur in any of these six patients. In conclusion, we could not find rationale for isoniazid prophylaxis in liver transplant recipients with past diagnosis of tuberculosis, when the disease is considered to be inactive. Tuberculosis should be considered as cause of post-transplant infections, and careful post-transplant observations are essential for an early diagnosis.  相似文献   
103.
BACKGROUND: The development of new surgical instruments and devices has facilitated the performance of esophagojejunostomy after total gastrectomy. However, total prevention of dehiscence of anastomoses remains difficult. We introduced a new procedure for esophagojejunostomy using a circular stapler, requiring sacrifice of only a small part of the jejunum. METHODS: The study group comprised 390 consecutive patients who underwent reconstruction by Roux-en-Y esophagojejunostomy, performed with a circular stapler, sacrificing a small part of the jejunum after total gastrectomy. We assessed anastomotic leakage and anastomotic stenosis after surgery. RESULTS: Only 2 patients (0.5%) had leakage and 4 (1.0%) had anastomotic stenosis after reconstruction. All the patients were cured by conservative therapy. CONCLUSIONS: Esophagojejunostomy performed with a circular stapler after total gastrectomy, with sacrifice of only a small part of the jejunum, is a useful and easy procedure, with a leakage rate of 0.5%.  相似文献   
104.
BACKGROUND: Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a potent inducer of apoptosis in a wide variety of tumor cells, while it has no toxicity for the majority of normal cells.Therefore, TRAIL may be a suitable agent for anticancer therapy. We previously reported that a number of pancreatic cancer cell lines show resistance to TRAIL-induced apoptosis via overexpression of XIAP and FLIP. The present study was conducted to further examine TRAIL-based therapeutic strategies by aiming to restore functional apoptotic pathways in resistant pancreatic cancer cells. METHODS: In various pancreatic cancer cell lines, TRAIL-induced apoptosis was evaluated in the presence or absence of an XIAP-inhibitor (Smac peptide). Second, TRAIL-induced apoptosis was evaluated in TRAIL-resistant AsPC-1 cells with or without FLIP antisense. Third, the combined effect of Smac peptide and FLIP antisense was tested, and the activation of apoptosis-related caspases and poly (ADP-ribose) polymerase was evaluated. Finally, TRAIL-induced apoptosis was evaluated in the presence or absence of FLIP antisense and an XIAP inhibitor (embelin). RESULTS: Smac peptide enhanced TRAIL-induced apoptosis in a dose-dependent manner for several pancreatic cancer cell lines, but showed no effect on TRAIL-resistant AsPC-1 cells. Smac peptide alone had no influence on cell viability. TRAIL-induced apoptosis was restored in TRAIL-resistant AsPC-1 cells by exposure to FLIP antisense, which suppressed the expression of FLIP. The effect of TRAIL was augmented by the combination of FLIP antisense and Smac peptide. Similarly, TRAIL-induced apoptosis was restored by the combination of FLIP antisense and embelin. Activation of apoptotic caspases and cleavage of poly (ADP-ribose) polymerase was observed after sensitization of TRAIL-resistant pancreatic cancer cells. CONCLUSIONS: Pancreatic cancer cells gain resistance to TRAIL-induced apoptosis via expression of the antiapoptotic proteins XIAP and FLIP. Smac peptide and FLIP antisense could restore the apoptotic effect of TRAIL. An XIAP inhibitor, embelin, enhanced the effect of TRAIL in the presence of FLIP antisense. These findings may provide useful information for the development of TRAIL-based therapeutic strategies by restoring functional apoptotic pathways in resistant pancreatic cancer cells. In addition, a low molecular weight XIAP inhibitor like embelin could be a lead compound for the development of effective XIAP inhibitors.  相似文献   
105.
An insufficient remnant in extended hepatectomy and small-for-size graft in liver transplantation are critical matters in the field of liver surgery, and reliable and reproducible animal models that can provide clinically relevant and reliable data are needed. We herein describe our detailed surgical procedures for performing 70 % hepatectomy in pigs, and discuss the critical anatomical features, key techniques and pitfalls based on our experience. The porcine liver is divided into four lobes. The right lateral lobe (RLL) accounts for 30 % of the liver volume. Important points, such as selective temporal clamping of the arterial branch, confirmation of a related demarcation line, a two-step process to skeletonize Glisson’s capsules during liver resection and selective ligation of the portal venous branch to the right medial lobe without inducing any subtle injuries to Glisson’s capsules from the RLL to common bile duct, are discussed.  相似文献   
106.

Background

Renal inulin clearance is the gold standard for evaluation of kidney function, but is compromised by problems of collecting urine samples in children, especially those <6 years or with a bladder dysfunction. Therefore, we should utilize the serum cystatin C (cysC)-based estimated glomerular filtration rate (eGFR) for measuring serum cysC. The purpose of the present study is to determine the applicability of the new serum cysC-based eGFR in Japanese children and adolescents, including infants with chronic kidney disease (CKD), for evaluation of renal function.

Methods

Inulin clearance and standardized serum cysC level determined by the colloidal gold immunoassay were measured in 135 pediatric CKD patients between the ages of 1 month and 18 years with no underlying disease that affects renal function except CKD, to determine serum cysC-based eGFR in Japanese children and adolescents.

Results

We showed the inulin clearance by expression of 1/serum cysC in pediatric CKD patients, which resulted in the equation: inulin GFR (mL/min/1.73 m2) = 104.1 × 1/serum cysC (mg/L) ? 7.80. We also validated the cysC-based eGFR formula for Japanese adults. eGFR values obtained with the adult formula significantly underestimated GFR by approximately 8 % in children with CKD.

Conclusion

We determined the new cysC-based eGFR formula is useful for clinical screening of renal function in Japanese children and adolescents, including infants.  相似文献   
107.

Purpose

The role of gastrectomy for patients with positive peritoneal cytology, but a negative macroscopic peritoneal implant (P?/cy+), remains unclear. The aim of this study was to evaluate laparoscopic gastrectomy for P?/cy+ patients.

Methods

This study reviewed a prospectively maintained gastric cancer database of gastric-cancer patients those underwent surgical resection. P?/cy+ gastric cancer that had invaded the subserosa, or deeper layers, of the stomach wall without distant organ metastases was considered operable in this institution. P?/cy+ patients underwent either open or laparoscopic gastrectomy with D2 lymphadenectomy. The short-term results were examined to assess differences in outcome between the two groups.

Results

Eighteen P?/cy+ patients without distant organ metastases underwent surgery between 2000 and 2010. Laparoscopic gastrectomy was performed in nine patients and open gastrectomy in nine patients. The estimated blood loss was significantly smaller, the resumption of food intake earlier, and the length of postoperative hospital stay shorter in the patients that underwent laparoscopic gastrectomy than in the patients that underwent open gastrectomy. There were no significant differences in the 2-year survival rates between the groups.

Conclusion

Laparoscopic gastrectomy for P?/cy+ patients is a minimally invasive and safe oncologic procedure with good short-term results.  相似文献   
108.
We investigated the antiarrhythmic effect of beta-blocking agents. Using 35 anesthetized dogs, the chest was opened and the left anterior descending coronary artery (LAD) was ligated for 30 min and the ventricular multiple response threshold (VMRT) was observed in the time course. The dogs were divided into five groups premedicated intravenously ten min before LAD ligation with either isotonic saline (the control group), D,L-propranolol (0.5 mg/kg), D-propranolol (0.5 mg/kg), D,L-pindolol (0.1 mg/kg), or D,L-acebutolol (2.5 mg/kg). Thirty min after ligation, myocardial mitochondria were prepared from the ischemic and the non-ischemic areas, and then the content of mitochondrial long-chain acyl-CoA and Ca++-binding activity were measured. The value of VMRT 1.59 +/- 0.21 mA before ligation decreased to 0.99 +/- 0.13 mA 30 min after ligation. Content of acyl-CoA in mitochondria from the ischemic area increased significantly compared to those from the non-ischemic area. Mitochondrial Ca++-binding activity in the ischemic area decreased significantly compared to that in the non-ischemic area. Each administration of three beta-blocking agents prevented the decreases in VMRT and Ca++-binding activity and excessive accumulation of acyl-CoA; D-propranolol had no effect. These results suggest that the antiarrhythmic action of beta-blocking agents is based, at least in part, on the protection from decrease in Ca++-binding activity due to mitochondrial dysfunction induced by the excessive accumulation of long-chain acyl-CoA in mitochondria.  相似文献   
109.
The effect of Coenzyme Q10 on reperfusion injury in canine myocardium   总被引:2,自引:0,他引:2  
The mechanism of mitochondrial damage during reperfusion injury of ischemic myocardium was studied using mongrel dogs in vivo and isolated mitochondria in vitro. Seventy-seven adult dogs were divided into three groups: the control group (n = 38), the Coenzyme Q10 (CoQ10)-5 mg group (n = 24), and the CoQ10-15 mg group (n = 15). In the control group, the left anterior descending coronary artery (LAD) of the dog was occluded for 15 min followed by 5 min of reperfusion after 40 min of premedication with physiological saline. In both CoQ10 groups, 5 mg/kg or 15 mg/kg of CoQ10 was infused intravenously for 20 min and then physiological saline was administered for 20 min before 15 min occlusion of the LAD. Subsequently, reperfusion was allowed for 5 min. Each group was further divided into two subgroups depending on the presence (arrhythmia group) or the absence (non-arrhythmia group) of ventricular arrhythmias. Immediately after 15 min occlusion, myocardial samples were taken from the normal and reperfused areas to measure CoQ10 content of myocardium. Heart mitochondria were prepared after 5 min of reperfusion from both areas. Arrhythmias appeared in 12 of 38 dogs in the control group (32%), two of 24 dogs in the CoQ10-5 mg group (8%) and none of 15 dogs in the CoQ10-15 mg group (0%). Premedication with CoQ10 increased tissue CoQ10 content in a dose-dependent manner. In the CoQ10-5 mg group, the increase in CoQ10 content of dogs with reperfusion arrhythmias was relatively less than that of dogs without reperfusion arrhythmias. In each group, mitochondrial function was decreased in the arrhythmia group compared to that of the non-arrhythmia group. The increase in free fatty acid (FFA) content and the decrease in phospholipid content were also observed in mitochondria from the reperfused area of each arrhythmia group. The increase in FFA and mitochondrial dysfunction were induced by the incubation of mitochondria in vitro with phospholipase (PLase) A2 or PLase C, and protected by the addition of CoQ10. These results suggest that PLase plays an important role in the development of mitochondrial damage associated with reperfusion.  相似文献   
110.
Introduction: A new method to evaluate whole plantar nerve conduction with disposable strip electrodes (DSEs) is described. Methods: Whole plantar compound nerve action potentials (CNAPs) were recorded at the ankle. DSEs were attached to the sole for simultaneous stimulation of medial and lateral plantar nerves. We also conducted medial plantar nerve conduction studies using an established method and compared the findings. Results: Whole plantar CNAPs were recorded bilaterally from 32 healthy volunteers. Mean baseline to peak amplitude for CNAPs was 26.9 ± 11.8 μV, and mean maximum conduction velocity was 65.8 ± 8.3 m/s. The mean amplitude of CNAPs obtained by our method was 58.2% higher than that of CNAPs obtained by the Saeed method (26.9 μV vs. 17.0 μV; P < 0.0001). Conclusions: The higher mean amplitude of whole plantar CNAPs obtained by our method suggests that it enables CNAPs to be obtained easily, even in elderly people. Muscle Nerve 53: 209–213, 2016  相似文献   
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