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71.

Background

This retrospective study evaluated the surgical learning curve and outcomes of thoracolaparoscopic esophagectomy.

Patients and Methods

The study group comprised a series of 92 patients with preoperatively diagnosed resectable thoracic esophageal cancer. Additionally, the surgical outcomes in 79 esophageal cancer patients receiving open esophagectomies were compared. All patients underwent thoracolaparoscopic esophagectomy in the lateral decubitus position. The short- and long-term outcomes were evaluated, and the surgical learning curve was assessed.

Results

The total operation time was 477.8?±?102.2 min, the thoracoscopic time was 157.9?±?61.3 min, the total blood loss was 554.4?±?280.5 ml, and the number of retrieved lymph nodes was 34.3?±?14.3. Postoperative morbidity was observed in 23 patients. After the surgeon??s first 40 cases, the surgical technique and short-term outcomes were stable. The 5-year disease-specific survival was 66.6% and the 5-year overall survival was 64.6% in patients receiving R0 thoracolaparoscopic esophagectomy. Comparison of 5-year disease-specific survival rate according to tumor?Cnode?Cmetastasis stage between patients receiving R0 thoracolaparoscopic esophagectomy and conventional open esophagectomy showed that there were no significant differences in survival in any stage between the two groups. Loco-regional recurrence was observed in 6 patients, distant recurrence in seven, and combined recurrence in nine after R0 thoracolaparoscopic esophagectomy. There was no significant difference in the pattern of recurrence between the two groups.

Conclusions

Thoracolaparoscopic esophagectomy for esophageal cancer was technically feasible and oncologically satisfactory, according to the surgical learning curve.  相似文献   
72.
Catamenial pneumothorax is a subclass of secondary spontaneous pneumothorax occurring in women in their third or fourth decade of life. We describe a classic and typical case of this disease. Although it is believed to be rare historically, the recent study showed the much higher prevalence. It is essential to consider this disease in recurrent spontaneous pneumothorax of a middle-aged woman.  相似文献   
73.
BACKGROUND: Pulmonary metastasectomy has become the standard therapy for various metastatic malignancies to the lungs; however, few data have been available about lung metastasectomy for hepatocellular carcinoma. To confirm the role for resection of pulmonary metastases for such tumors, we reviewed our institutional experience. METHODS: Between 1993 and 2005, 12 patients with pulmonary metastases from hepatocellular carcinomas underwent complete pulmonary resection. All patients had undergone curative resection of their primary hepatocellular carcinomas and also had obtained or had obtainable locoregional control of their primaries. Various perioperative variables were investigated retrospectively to analyze the possible prognostic factors for overall survival and pulmonary metastases-free survival after pulmonary metastasectomy. RESULTS: Nine patients were male and three were female (median age, 53 (range, 43-80) years). Overall survival rate after metastasectomy was 80.8%, 57.7%, and 28.9% at 1, 2, and 5 years, respectively. Pulmonary metastases-free survival rate was 64.2%, 32.1%, and 21.4% at 1, 2, and 5 years, respectively. Five patients presented recurrences in the remaining liver before pulmonary metastases, but hepatic recurrences at this interval did not affect an overall survival after pulmonary metastasectomies. Two patients had undergone living-related liver transplantation. The maximum tumor size of the pulmonary metastasis < 3 cm was the only favorable prognostic factor for overall survival (P = 0.0006), whereas there was no significant prognostic factor for pulmonary metastases-free survival. CONCLUSIONS: Pulmonary metastasectomy for hepatocellular carcinoma in selected patients was well justified when the maximum tumor size was <3 cm.  相似文献   
74.
We report a successful complex mitral valve plasty using port access minimally invasive cardiac surgery for congenital mitral regurgitation that presented as an abnormality of the subvalvular apparatus. A 16-year-old male patient received a diagnosis of mitral regurgitation resulting from tethering of the anterior mitral leaflet and posterior mitral leaflet caused by an abnormality in papillary muscle insertion and a hypoplastic chordae tendineae. The posterior leaflet was closely tethered to the tips of the papillary muscle with essentially no chordae tendineae. The flexibility of the leaflet was restored by surgically removing the abnormal chordae, and reconstruction of chordae tendinae of the anterior leaflet was carried out using three loops and of the posterior leaflet using one loop with a loop technique method. As an additional procedure for persistent regurgitation, an edge-to-edge technique to the posterior commissure side was performed, after which the mitral regurgitation disappeared.  相似文献   
75.
BACKGROUND AND OBJECTIVE: Matrix metalloproteinase-2 (MMP-2) degrades both fibrillar collagens and elastin. MMP-2 is secreted as a latent 72-kd proenzyme that must be proteolytically processed to the 62-kd active form. In our laboratory we demonstrated a significant increase of active, matrix-bound MMP-2 in abdominal aortic aneurysmal (AAA) tissue compared with nonaneurysmal aorta with arteriosclerotic occlusive disease and normal aortic tissue. This increase in active MMP-2 is considered to be important in aneurysm pathogenesis, but the mechanism of its activation in aortic tissue is unknown. Membrane type-1 MMP (MT-1 MMP) is known to be an activator of MMP-2. The purpose of this study was to determine MT-1 MMP expression and its involvement in pro-MMP-2 activation in human aneurysmal tissue. METHODS: Infrarenal aortic tissue was obtained during the surgical repair of AAAs or the bypass of aortoiliac occlusive disease, or from nondiseased aorta, and the expression of MT-1 MMP messenger RNA was determined with Northern blot analysis. MT-1 MMP protein was determined with immunoblot and immunohistochemistry. The ability of aortic tissue to activate pro-MMP-2 was analyzed by incubating aortic tissue with exogenous radiolabeled pro-MMP-2. RESULTS: MT-1 MMP messenger RNA and protein are increased in AAA (P <.05) compared with arteriosclerotic occlusive disease and normal aortic tissue. Immunohistochemical analysis localized MT-1 MMP to aortic smooth muscle cells and macrophages in aneurysmal tissue. AAA tissue demonstrated a greater capacity to activate exogenous pro-MMP-2 compared with atherosclerotic and normal aortic tissue (P <.05). CONCLUSION: These studies demonstrate that MT-1 MMP is increased in AAA tissue and suggest that it may be important in AAA pathogenesis through its ability to activate pro-MMP-2  相似文献   
76.
Takotsubo cardiomyopathy (TCM) is a relatively new concept in cardiovascular disease. The clinical symptoms of TCM are similar to those of a myocardial infarction, but both the mechanism and the management of TCM are different from those of myocardial infarction. The cause of TCM is unclear, but it is suggested to occur in conjunction with excessive circulating catecholamines due to stress. Thus, control of the stress reaction and restriction of catecholamine levels are considered important for prevent of TCM onset. We report the dental management of a patient with intellectual disability who had anamnesis of TCM and cardiopulmonary arrest under restraint during a previous dental appointment in another dental clinic. We used intravenous sedation with both midazolam and propofol, by which the excessive hormonal reaction that caused TCM onset and cardiopulmonary arrest was controlled, for dental treatment in our facility. All planned dental treatment was then performed without any problems.  相似文献   
77.
BACKGROUND: Immune regulatory CD4+CD25+ T (regulatory T; Treg) cells play a vital role in the induction and maintenance of self-tolerance. They are essential for the homeostasis of T cells, the prevention of autoimmunity, and the induction of tolerance to allogeneic donor grafts. However, the underlying mechanism of their functions remains mostly elusive. Therefore, we investigated here a crucial role of Treg cells in their response to alloantigen via the programmed death (PD)-1/PD-1 ligand (PD-L1) pathway. METHODS: In vitro mixed lymphocyte reaction (MLR) assay, graft-versus-host disease (GvHD) and a skin transplantation model were used to evaluate the mechanisms of PD-1/PD-L1 pathway. RESULTS: Blockade of the PD-1/PD-L1 pathway using anti-PD-L1 monoclonal antibodies (mAb) is found to inhibit Treg cell's ability to suppress and restore CD4+CD25-T-cell proliferation in vitro. GvHD was lethal after adoptive transfer of allogeneic C57BL/6 (H-2K) spleen cells to NOD/SCID (H-2K) mice unless CD25+ T cells were also included. Strikingly, the suppression of GvHD by CD25+ cells was abrogated by anti-PD-L1 mAb administration. The abrogation of Treg-cell-mediated suppression could also be demonstrated in a Balb/c (H-2K) to B6/Rag-2KO (H-2K) skin-allograft model. CONCLUSIONS: The blockade of the PD-1/PD-L1 pathway abrogates Treg-mediated immunoregulation, thus suggesting that the PD-1/PD-L1 pathway is required for Treg suppression of the alloreactive responses of CD4+CD25-T cells. This finding has important implications for clarifying the mechanisms of allograft rejection and GvHD.  相似文献   
78.
OBJECT: In an attempt to improve peripheral nerve repair, the influence of the addition of reverse end-to-side neurorrhaphy for an injured peripheral nerve was investigated in the rat sciatic nerve transection model. METHODS: Twelve Sprague-Dawley rats were divided into two groups (six rats in each group). In Group I, the right sciatic nerve was cut at a point distal to the gluteal notch and repaired using end-to-end neurorrhaphy with four 10-0 nylon epineurial sutures. In Group II, after performing the same procedure as in Group I, the left sciatic nerve was cut distally and passed through a subcutaneous tunnel to the right side. The proximal stump of the left sciatic nerve was coapted to the epineurial window of the right sciatic nerve distal to the injured point in an end-to-side fashion using 10-0 nylon epineurial sutures. The effects were evaluated using analgesimeter recordings for the hind paw, electrophysiological tests, measurement of the muscle contraction force, a double-labeling technique, weight measurement and histological examination of the gastrocnemius muscle, histological examination of the bilateral sciatic nerves, and immunofluorescent staining. RESULTS: Results from the many tests used to evaluate the reverse end-to-side neurorrhaphy technique indicated that functional recovery of the denervated target organs was promoted by axonal augmentation. CONCLUSIONS: The reverse end-to-side neurorrhaphy technique could be useful in peripheral nerve repair.  相似文献   
79.
80.
OBJECTIVE: A randomized controlled trial was conducted to clarify the effectiveness of intraoperative blood salvage in reducing blood loss. BACKGROUND: Although reduction of central venous pressure (CVP) is thought to decrease blood loss during liver resection, no consistently effective and safe method for obtaining the desired reduction of CVP has been established. METHODS: Living liver donors scheduled to undergo liver graft procurement were randomly assigned to a blood salvage group, in which a blood volume equal to approximately 0.7% of the patient's body weight was collected before the liver transection, or a control group. The surgeons were blinded to the randomization results. The primary outcome measure was blood loss during liver parenchymal division. A multivariate analysis was also performed. RESULTS: Seventy-nine donors were allocated intraoperatively to the blood salvage group (n = 40) or the control group (n = 39). The amount of blood loss during liver transection was significantly smaller in the blood salvage group than in the control group (median loss during transection, 140 mL vs. 230 mL, P = 0.034). The CVP at the beginning of the liver parenchymal division was significantly lower in the blood salvage group than in the control group (median, 5 cm H2O vs. 6 cm H2O, P = 0.005). The results of a multivariate analysis revealed that intraoperative blood salvage offered the advantage of reduced blood loss during liver parenchymal division (adjusted OR, 0.31; 95% CI, 0.11-0.85, P = 0.025). CONCLUSION: Modest intraoperative blood salvage significantly and safely reduced blood loss during hepatic parenchymal transection.  相似文献   
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