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81.

Background/Purpose

Development of indirect inguinal hernia and hydrocele in childhood is readily explained by the persistence of smooth muscle component around the processus vaginalis (PV) after the descent of the testis into the scrotum. The aim of this study was to investigate the expression of smooth muscle myosin heavy chain (SM MHC) isoforms as the markers of smooth muscle cell (SMC) differentiation in childhood inguinal hernia and hydrocele and in age-matched controls.

Methods

The authors analyzed sacs from patients with inguinal hernia (male, 10; female, 10) and hydrocele (n = 10) immunohistochemically using monoclonal antibodies against α-smooth muscle actin, SM1, SM2 and SMemb. Peritoneal samples (male, 5; female, 5) obtained from age-matched patients served as controls. Immunostaining was evaluated with semiquantitative scoring and χ2 test.

Results

The expression pattern of SM MHC isoforms did not differ among sacs obtained from female inguinal hernia when compared with that of controls. However, strong expression of SMemb within the sac walls of male inguinal hernia and SM1 in hydrocele groups were observed.

Conclusions

Our results indicate that SMC differentiation may play an important role in the obliteration of processus vaginalis in male inguinal hernia and hydrocele after the descent of the testis.  相似文献   
82.
Objectives: To report our initial experience with transumbilical laparo‐endoscopic single‐site adrenalectomy for adrenal tumors by using a single port with a multichannel cannula and bent laparoscopic instrumentation. Methods: Between December 2009 and December 2010, 30 patients underwent transumbilical laparo‐endoscopic single‐site adrenalectomy at our hospital. The procedure was carried out for adrenal cortical adenoma in 17 patients, adrenal pheochromocytoma in seven patients and other types of tumors in six patients. A multichannel port, bent laparoscopic instruments and Opti4 laparoscopic electrodes were used in all patients. The intraperitoneal space was approached through the umbilicus. The multichannel port was placed through a 2‐cm incision at the inner edge of the umbilicus. A 5‐mm flexible laparoscope was introduced to maintain an adequate laparoscopic view, and surgical specimens were extracted using an Endocatch bag. Results: All procedures were successfully completed, with only one incision through the umbilicus, and without conversion to a standard laparoscopic approach. Mean operative time was 120.1 ± 34.7 min. Tumor laterality and patient body mass index did not affect surgical morbidity. The initial 15 patients had a significantly longer mean pneumoperitoneum time (95.8 ± 37.5 min) than the last 15 patients (70.5 ± 18.7 min). Only one postoperative complication was observed (postoperative hematoma). Conclusions: A transumbilical approach for laparo‐endoscopic single‐site adrenalectomy is safe and feasible, and it results in superior cosmesis. Improvements in surgical devices might facilitate further development of this approach.  相似文献   
83.

Background

Laparoscopic inguinal hernia repair is associated with a decrease in postoperative pain, shortened hospital stay, earlier return to normal activity, and decrease in chronic pain. Moreover, laparoscopic surgery performed with needlescopic instruments has more advantages than conventional laparoscopic surgery. However, there are few reports of large-scale laparoscopic transabdominal preperitoneal inguinal hernia repair using needlescopic instruments (nTAPP). This report reviews our experiences with 352 nTAPP in 317 patients during the 15-year period from April 1996 to April 2011.

Methods

We performed nTAPP as the method of choice in 88.5% of all patients presenting with inguinal hernia. To perform the nTAPP, 3-mm instruments were used. A 5-mm laparoscope was inserted from the umbilicus, and surgical instruments were inserted through 5- and 3-mm trocars. After reduction of the hernia sac and dissection of the preperitoneal space, we placed polyester mesh or polypropylene soft mesh with staple fixation. The peritoneum was closed with 3–0 silk interrupted sutures.

Results

The mean operative time was 102.9?min for unilateral hernias and 155.8?min for bilateral hernias. There was no conversion to open repair. Forty-three patients (13.6%) used postoperative analgesics, and the mean frequency of use was 0.5 times. Regarding intraoperative complications, we observed one bladder injury, but no bowel injuries or major vessel injuries. Postoperative complications occurred in 32 patients (10.1%). One patient with a retained lipoma required reoperation. There was no incidence of chronic pain or mesh infection. The operative time for experienced surgeons (≥20 repairs) was significantly shorter than that of inexperienced surgeons (<20 repairs; P?Conclusions The nTAPP was a safe and useful technique for inguinal hernia repair. Large prospective, randomized controlled trials will be required to establish the benefit of nTAPP.  相似文献   
84.

Background

Laparoscopy-assisted gastrectomy (LAG) is becoming widely used for early gastric cancer. However, how the curability and long-term prognosis of LAG and open gastrectomy (OG) for early and advanced gastric cancer compare remains unclear. This study assessed short- and long-term outcomes after LAG with lymph node dissection in early and advanced gastric cancer.

Methods

A total of 332 patients who underwent LAG or OG for early and advanced gastric cancer from January 2001 through December 2010 were reviewed retrospectively. The mean operating time, estimated mean blood loss, number of dissected lymph nodes, and survival rates were compared between LAG and OG for early and advanced gastric cancer.

Results

Overall, 47.6% (158/332) of patients underwent LAG; D1, D1+ lymph node dissection was carried out in 77.2%, with D2 dissection in 22.8%. Only one patient required conversion to OG. Comparing LAG and OG with D1, D1+ lymph node dissection for early gastric cancer (EGC), mean operating time was significantly longer, estimated mean blood loss was significantly smaller, and the average number of retrieved lymph nodes was significantly greater with LAG. The rate of specific postoperative morbidity was 17.2% for LAG patients and 25.0% for OG patients, with no postoperative mortality. Survival and recurrence rates were not significantly different. Comparing LAG and OG with D2 lymph node dissection for advanced gastric cancer (AGC), mean operating time was significantly longer and estimated mean blood loss was significantly smaller with LAG, while the average number of retrieved lymph nodes, specific postoperative morbidity and mortality, and survival and recurrence rates were not significantly different.

Conclusions

LAG with D1, D1+ lymph node dissection for EGC is safe and equivalent to open gastrectomy in curability. Moreover, LAG with D2 lymph node dissection for AGC is comparable to OG with D2 lymph node dissection with regard to short- and long-term results.  相似文献   
85.
Blood compatibility of a ventricular assist device (VAD) depends on the dynamics of blood flow. The focus in most previous studies was on blood flow in the VAD. However, the tip shape and position of the VAD inflow cannula influence the dynamics of intraventricular blood flow and thus thrombus formation in the ventricle. In this study, blood flow in the left ventricle (LV) under support with a catheter-type continuous flow blood pump was investigated. The flow field was analyzed both numerically and experimentally to investigate the effects of catheter tip shape and its insertion depth on intraventricular flow patterns. A computational model of the LV cavity with a simplified shape was constructed using computer-aided design software. Models of catheters with three different tip shapes were constructed and each was integrated to the LV model. In addition, three variations of insertion depth were prepared for all models. The fully supported intraventricular flow field was calculated by computational fluid dynamics (CFD). A transparent LV model made of silicone was also fabricated to analyze the intraventricular flow field by the particle image velocimetry technique. A mock circulation loop was constructed and water containing tracer particles was circulated in the loop. The motion of particles in the LV model was recorded with a digital high-speed video camera and analyzed to reveal the flow field. The results of numerical and experimental analyses indicated the formation of two large vortices in the bisector plane of the mitral and aortic valve planes. The shape and positioning of the catheter tip affected the flow distribution in the LV, and some of these combinations elongated the upper vortex toward the ventricular apex. Assessment based on average wall shear stress on the LV wall indicated that the flow distribution improved the washout effect. The flow patterns obtained from flow visualization coincided with those calculated by CFD analysis. Through these comparisons, the numerical analysis was validated. In conclusion, results of these numerical and experimental analyses of flow field in the LV cavity provide useful information when designing catheter-type VADs.  相似文献   
86.

Purpose

This study was undertaken to elucidate the clinicopathological characteristics and surgical outcome of the periductal infiltrating (PI) type of intrahepatic cholangiocarcinoma (ICC), which is a distinct macroscopic type of ICC arising from the second-order of the intrahepatic bile ducts without apparent invasion of the surrounding liver parenchyma.

Methods

All patients with the PI type of ICC were identified from a database of patients with intrahepatic cholangiocellular carcinoma that underwent surgical resection between 1983 and 2009. The clinicopathological data of these patients were analyzed retrospectively.

Results

Sixteen of 203 patients (7.9%) had the PI type of ICC. The median survival was 7.7?years with 5-year survival rate of 62.1%. The PI type of ICC showed a significantly better survival than the mass-forming (MF) type (P?=?0.0293) or MF plus PI type of ICC (P?=?0.0001). Microscopic examinations showed intrahepatic metastasis to be absent in all the patients with PI type ICC. The incidence of intrahepatic metastases in patients with PI type was significantly lower in comparison to that of patients with MF type (P?=?0.0030) and MF plus PI type (P?=?0.0533), respectively.

Conclusion

Surgery could therefore provide a favorable outcome in patients with the PI type of ICC, probably due to its lower incidence of intrahepatic metastases.  相似文献   
87.
Kosugi C  Saito N  Kimata Y  Ono M  Sugito M  Ito M  Sato K  Koda K  Miyazaki M 《Surgery》2005,137(3):329-336
BACKGROUND: We investigated the correlation between operative procedures for rectal carcinoma and postoperative rectovaginal fistulas (RVF), and treatment for RVF. METHODS: The medical records of 161 female patients with rectal carcinoma were examined retrospectively with respect to the cause, incidence, and methods of treatment for RVF occurring after rectal cancer operations, and to the outcomes of gluteal-fold flap repairs for RVF. RESULTS: Of the 161 patients, 16 developed RVF clinically. The incidence of RVF was significantly higher in patients who were anastomosed by the double stapling technique (DST) and had concomitant resection of the vaginal wall. No statistical difference was found between the established diverting ostomy group and the no-stoma group. Six patients recovered by the establishment of a diverting ostomy only. The gluteal-fold flap technique was performed for 5 patients. No RVF recurrences were noted in these 5 patients. CONCLUSIONS: The incidence of RVF was higher in the patients who were anastomosed by DST or had concomitant resection of the vaginal wall. Although some RVFs heal with only fecal diversion, for patients in whom RVF is caused by involvement of the vaginal wall in the circular staple or intersphincteric resection, good results are obtained with the gluteal-fold flap repair technique.  相似文献   
88.
BACKGROUND: Parathyroid hormone-related protein (PTHrP) is produced by cancer cells and has been suggested to be responsible for malignancy-associated hypercalcemia and osteolysis after bone metatsases. Therefore, PTHrP is a promising target in the treatment of metastatic prostate cancer. METHODS: Seven PTHrP-derived peptides were prepared based on the HLA-A2 binding motif. These peptide candidates were screened by their ability to induce peptide-specific cytotoxic T lymphocytes (CTLs), and their ability to be recognized by immunoglobulin G (IgG). RESULTS: Both the PTHrP59-67 and PTHrP42-51 peptides were found to efficiently induce peptide-specific CTLs from peripheral blood mononuclear cells of HLA-A2+ prostate cancer patients with several HLA-A2 subtypes. These CTLs showed HLA-A2-restricted cytotoxicity toward prostate cancer cells. IgG reactive to the PTHrP42-51 peptide was frequently detected in prostate cancer patients. CONCLUSIONS: These results indicate that these two new PTHrP peptides will be useful in the peptide-based immunotherapy of HLA-A2+ prostate cancer patients, especially those with bone metastases.  相似文献   
89.
90.

Objectives

To evaluate postmortem changes of the aorta on postmortem computed tomography (CT) in comparison with those on antemortem CT obtained in the same patients.

Materials and Methods

We studied 57 consecutive patients who had undergone antemortem CT, postmortem CT, and pathological autopsy in our tertiary care hospital between April 2009 and December 2010. Postmortem CT was performed within 20 h after death, followed by pathological autopsy. Pathological autopsy confirmed the absence of cardiovascular disease such as aortic aneurysm, aortic dissection, or Marfan syndrome in all patients. Aortic wall thickness and aortic cross-sectional areas were measured on both antemortem CT and postmortem CT. Difference in aortic wall thickness between antemortem CT with and without contrast medium, and between antemortem CT and postmortem CT, and in cross-sectional area of the aortic wall between antemortem CT and postmortem CT was evaluated statistically.

Results

No significant difference in aortic wall thickness was observed on antemortem CT in comparison of contrasted and non-contrasted images. The aortic wall was significantly thicker on postmortem CT than on antemortem CT (p?Conclusion This is the first longitudinal study to confirm greater thickness of the aortic wall on postmortem images compared with antemortem images in the same patients and to show no change in cross-sectional area of the aortic wall between before and after death.  相似文献   
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