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31.
We studied the effect of preoperative hepatocyte transplantation on the prevention of liver failure in cirrhotic rats after hepatic resection. Two groups of Lewis rats were rendered cirrhotic by i.p. injection of 1% dimethylnitrosamine and were subjected to 33% hepatectomy. Two days before the resection, 36 rats in group I received intrasplenic hepatocyte transplantation, and 25 rats in group II were given intrasplenic injection of normal saline as a control. By the end of the third postoperative day, the rats in group I had better survival and a better biochemical profile than those in group II. The liver growth rate and the labeling index of proliferating cell nuclear antigen (PCNA-LI) showed a steady rise in group I. Compared with group II, group I had a significantly lower transforming growth factor (TGF-beta1) level (p < 0.05). We conclude that preoperative intrasplenic hepatocyte transplantation improves survival and facilitates regeneration in cirrhotic rats after hepatic resection.  相似文献   
32.
1 (PGE1) on protecting against hepatic endothelial cell damage and increasing graft viability after cold preservation and reperfusion, using an isolated perfused rat liver (IPRL) model. The grafts were divided into three groups, according to the cold preservation time and PGE1 administration, namely: 4 h preservation (group 1, n = 9), 6 h preservation (group 2, n = 9), and 6 h preservation followed by PGE1 infusion (group 3, n = 9). After cold storage, the grafts were put on the recirculating IPRL system, then reperfused for 120 min at 37°C with oxygenated Krebs-Henseleit buffer containing hyaluronic acid (HA). To examine the function of the sinusoidal endothelial cells and hepatocytes, serial measurements of HA, tumor necrosis factor-α (TNFα), thromboxane B2 (TXB2), acid phosphatase, and conventional parameters in the perfusate were made. After perfusion, the trypan blue exclusion test was performed to assess the presence of any microscopic sinusoidal lining cell damage. In group 3, the bile output and HA clearance were significantly greater, while glutamic oxaloacetic transaminase, glutamic pyruvic transaminase, TNFα, TXB2, and acid phosphatase in the perfusate were significantly lower than in group 2. Histologically, less endothelial cell damage and hepatocyte damage than in group 2 was also confirmed. These results therefore suggest that the improvement of hepatic graft viability by PGE1 administration is mainly due to sinusoidal endothelial cell protection. (Received for publication on Nov. 21, 1996; accepted on Nov. 6, 1998)  相似文献   
33.
The aim of this study was to obtain quantitative iodine-123 brain single-photon emission tomographic (SPET) images with scatter and attenuation correction. We used a triple-headed SPET gamma camera system equipped with fan-beam collimators with a technetium-99m line transmission source placed at one of the focal lines of the fan-beam collimators. Four energy windows were employed for data acquisition: (a) 126–132 keV, (b) 132–143 keV, (c) 143–175 keV and (d) 175–186 keV. A simultaneous transmission-emission computed tomography scan (TCT-ECT) was carried out for a brain phantom containing 123I solution. The triple energy window scatter correction was applied to the 123I ECT data measured by means of the windows (b), (c) and (d) acquired by two detectors. Attenuation maps were reconstructed from 99mTc TCT data measured by means of the windows (a), (b) and (c) acquired by one detector. Chang’s iterative attenuation correction method using the attenuation maps was applied to the 123I ECT images. In the phantom study cross-calibrated SPET values obtained with the simultaneous mode were almost equal to those obtained with the sequential mode, and they were close to the true value, within an error range of 5.5%. In the human study corrected images showed a higher grey-to-white matter count ratio and relatively higher uptake in the cerebellum, basal ganglia and thalamus than uncorrected images. We conclude that this correction method provides improved quantification and quality of SPET images and that the method is clinically practical because it requires only a single scan with a 99mTc external source. Received 6 June and in revised form 27 July 1998  相似文献   
34.
We implanted 60 posterior stabilized total knee prostheses (P.F.C. Sigma, DePuy, Warsaw, USA). In 30 cases, we used a CT-free navigation system (Vector Vision, Brain LAB, Heimstetten, Germany), and in 30 matched-paired controls, we used a conventional manual implantation. We compared postoperative long-leg radiographs in the two groups. The results revealed a significant difference in favor of navigation. In addition, we compared the preoperative anteroposterior dimension of the femoral condyle with the postoperative value. While there were no significant differences in the preoperative anteroposterior dimension of the femoral condyle between the two groups, the postoperative value in the navigation group was significantly larger than that of the preoperative value. Therefore, surgeons using navigation systems should guard against the possibility of oversizing when determining the size of the femoral component.
Résumé Nous avons implanté 60 prothèses totales postéro-stabilisées du genou (P.F.C. Sigma, DePuy). Dans 30 cas nous avons utilisé un système de navigation sans scanner (Vector vision R, Laboratoire du Cerveau, Heimstetten, Allemagne) et dans 30 contrôles appairés nous avons utilisé une implantation manuelle habituelle. Nous avons comparé les grandes radiographies postopératoires des membres inférieurs dans les deux groupes. Les résultats ont révélé une différence notable en faveur de la navigation. De plus nous avons comparé la dimension antéro-postérieure du condyle fémoral avant lintervention avec la valeur postopératoire. Tandis quil ny avait pas de différence notable dans la dimension antéro-postérieure préopératoire du condyle fémoral entre les deux groupes, la valeur postopératoire dans le groupe de la navigation était nettement plus grande que la valeur préopératoire. Par conséquent les chirurgiens qui utilisent des systèmes de navigation doivent prendre garde à ne pas implanter un composant fémoral sur-dimensionné.
  相似文献   
35.
Ueda K  Suga K  Kaneda Y  Li TS  Ueda K  Hamano K 《The Annals of thoracic surgery》2004,77(3):1033-7; discussion 1037-8
BACKGROUND: Preoperative localization of the sentinel node basin would guide selective lymph node dissection. We tried to identify these nodal stations with indirect computed tomographic lymphography using a conventional extracellular contrast agent, iopamidol. METHODS: Eleven consecutive patients scheduled to undergo anatomic resection of suspected lung cancer, without lymphadenopathy, were given a peritumoral injection of undiluted iopamidol under computed tomography guidance, and lymphatic migration was assessed by multidetector-row helical computed tomography. RESULTS: There were no complications such as bleeding, pneumothorax, or allergic reactions. Enhanced nodes were detected in all but 1 patient who had diffuse lymph nodal calcification. Enhanced nodes were identified at 32 ipsilateral intrathoracic nodal stations (20 hilar stations and 12 mediastinal stations). The average length of the longer axis of the enhanced nodes was 4.8 mm (range, 3 to 8 mm), and the average attenuation of the enhanced nodes was 132 (range, 46 to 261) Hounsfield units. In 9 patients with confirmed lung cancer, enhanced nodes appeared at 26 nodal stations, and all apparent enhanced nodes were identified as actual lymph nodes at appropriate position during lymphadenectomy. None of the resected lymph nodes had metastatic involvement. CONCLUSIONS: Indirect computed tomographic lymphography with the peritumoral injection of iopamidol effectively depicts the drainage nodes unless they are diffusely calcified. Although further study is required, this method could guide selective lymph node dissection.  相似文献   
36.
OBJECTIVE: To minimize the neurological complications following cardiovascular surgery, it is essential to prevent an occurrence of cerebrovascular embolism and to detect and solve cerebral malperfusion without delay in the operating theater. Although we have introduced near-infrared spectroscopy (NIRS) monitoring for the purpose of detecting cerebral malperfusion, no criterion has been available. We searched for this criterion by examining the relationship of sustained drop in the regional oxygen saturation (rSO2) of the frontal lobes to the occurrence of neurological events. METHODS: The 59 consecutive patients undergoing aortic surgery with selective cerebral perfusion (SCP) were examined. The rSO2 was monitored throughout the surgery and the durations of drops in rSO2 to below 55% and those below 60% were determined for each patient. The durations of rSO2 drop and other surgery-related parameters were compared between the patients in whom neurological events occurred and those without such events. RESULTS: A total of 16 cases (27.1%) presented with neurological events. Newly developed cerebral infarction was documented in 6 of these 16 cases. Operation time and the durations for which rSO2 dropped were significantly longer for the 16 patients with neurological events than for the 43 patients without events (Op time: 546.8 versus 448.1 min, P=0.0064; rSO2 below 60%: 141.2 versus 49.8 min, P=0.0032; rSO2 below 55%: 66.6 versus 10.6 min, P=0.0011), while there was no significant difference in age, bypass time, aortic clamping time, SCP time, and circulatory arrest time between the two groups. In the 3 patients with infarcts suggestive to hypoperfusion, sustained decrease in rSO2 was observed, while it was not significant in the remaining 3 patients with infarcts suggestive to embolism. Among the 53 patients without infarction, transient neurological events occurred more frequently in patients with sustained drop in rSO2 below 55% for over 5 min (44.4% versus 5.7%, P=0.0014). CONCLUSIONS: A sustained drop in rSO2 during aortic surgery is closely related to the occurrence of neurological events following surgery. We recommend that recovery of drop in rSO2 below 55% should be addressed without delay. However, use of NIRS is limited for detecting embolic events or hypoperfusion in the basilar region.  相似文献   
37.
A 41-year-old male patient with hepatitis B underwent right tri-segmentectomy and total caudate lobectomy for a huge hepatocellular carcinoma associated with complete occlusion of the inferior vena cava with thrombosis of the infrahepatic inferior vena cava due to tumor compression. Five months later, he was readmitted for ascites and hyperbilirubinemia. Venography revealed stenosis and tortuosity of the left hepatic vein and the inferior vena cava, for which balloon angioplasty of the left hepatic vein and the inferior vena cava was performed using an 8-mm and 10-mm balloon, respectively. The left hepatic venous pressure decreased from 65 mmHg to 25 mmHg after dilatation. The patient made a satisfactory recovery thereafter and remains well with normal liver functions and without ascites. Balloon angioplasty may be useful for liver failure due to hepatic vein stenosis after hepatic resection.  相似文献   
38.
BACKGROUND: Endoscopic thoracic sympathectomy has been considered an effective treatment for palmar hyperhidrosis. However, the extent of resection has not been determined in terms of efficacy and complications. We compared the efficacy and complications of 2-ganglion and single-ganglion resection in patients with palmar hyperhidrosis. METHODS: From 1995 to 2000, 75 patients underwent resection of thoracic ganglion T2 and T3. From 2000 to 2003, 67 patients underwent resection of only the T2 ganglion. Eighty of the 142 patients (56%) answered a detailed questionnaire, the results of which were analyzed. RESULTS: Gender, age, family history, and distribution of sweating were similar in both groups. Recurrence rates 1 and 2 years after endoscopic thoracic ganglionectomy were between 0% and 3% in T2 and T3 resection, and between 15% and 19% in T2 resection only. In the combined T2 and T3 resection group, 100% of patients noticed compensatory sweating; in T2 resection, 90% of patients noticed compensatory sweating. As for rates of satisfaction, T2 and T3 resection was superior to T2 resection. CONCLUSIONS: High recurrence rates of palmar hyperhidrosis after single-ganglion resection are reported in the present study. Two-ganglion resection is a superior surgical method to prevent recurrence of palmar hyperhidrosis.  相似文献   
39.
Background  In perioperative management of hepatic resection for hepatocellular carcinoma, excessive blood loss and blood transfusion greatly influence postoperative complications and prognosis of the patients. We evaluated the influence of blood products use on postoperative recurrence and prognosis of patients with hepatocellular carcinoma. Methods  The subjects were 66 patients who underwent elective hepatic resection for hepatocellular carcinoma without concomitant microwave or radiofrequency ablation therapy nor other malignancies between January 2001 and June 2006. We retrospectively investigated the influence of the use of blood products including red cell concentration and fresh frozen plasma on recurrence of hepatocellular carcinoma and overall survival. Results  In multivariate analysis, the dose of blood products transfusion was a significant predictor of disease-free and overall survival. Both disease-free and overall survival rates of those who were given blood products were significantly worse than those who did not receive. On the other hand, in univariate analysis of disease-free and overall survival after hepatic resection and clinical variables, the amount of blood loss was not a significant predictor of recurrence or death. Conclusion  Transfusion of blood products is associated with increased recurrence rate and worse survival after elective hepatic resection for patients with hepatocellular carcinoma.  相似文献   
40.

OBJECTIVE

Phosphorylation of two members of the TBC1 domain family of proteins, Akt substrate of 160 kDa (AS160, also known as TBC1D4) and TBC1D1, has been implicated in the regulation of glucose transport in skeletal muscle. Insulin-stimulated phosphorylation (measured using the phospho-Akt substrate [PAS] antibody) of AS160 and TBC1D1 appears to occur in an Akt-dependent manner, but the kinases responsible for contraction-stimulated PAS-AS160 and PAS-TBC1D1 remain unclear. AMP-activated protein kinase (AMPK) and Akt, both activated by contraction, can each phosphorylate AS160 and TBC1D1 in cell-free assays.

RESEARCH DESIGN AND METHODS

To evaluate the roles of AMPK and Akt on insulin- or contraction-stimulated PAS-AS160, PAS-TBC1D1, and glucose transport, rat epitrochlearis was incubated with and without compound C (inhibitor of AMPK) or Wortmannin (inhibitor of phosphatidylinositol [PI] 3-kinase, which is upstream of Akt) before and during insulin stimulation or contraction.

RESULTS

Insulin-stimulated glucose transport and phosphorylation of both AS160 and TBC1D1 were completely inhibited by Wortmannin. Wortmannin eliminated contraction stimulation of phospho-Ser21/9glycogen synthase kinase 3α/β (pGSK3; Akt substrate) and PAS-AS160 but did not significantly alter pAMPK, phospho-Ser79acetyl CoA carboxylase (pACC; AMPK substrate), PAS-TBC1D1, or glucose transport in contraction-stimulated muscle. Compound C completely inhibited contraction-stimulated pACC and PAS-TBC1D1 and partially blocked glucose transport, but it did not significantly alter pAkt, pGSK3, or PAS-AS160.

CONCLUSIONS

These data suggest that 1) insulin stimulates glucose transport and phosphorylation of AS160 and TBC1D1 in a PI 3-kinase/Akt–dependent manner, 2) contraction stimulates PAS-AS160 (but not PAS-TBC1D1 or glucose transport) in a PI 3-kinase/Akt–dependent manner, and 3) contraction stimulates PAS-TBC1D1 and glucose transport (but not PAS-AS160) in an AMPK-dependent manner.Insulin and contractile activity, the two most important physiological stimuli that increase glucose transport in skeletal muscle, can each induce the translocation of GLUT4 glucose transporters from the cell''s interior to its surface membranes (1,2). However, they regulate glucose transport via distinct signaling pathways (3). Insulin-stimulated glucose transport requires phosphatidylinositol (PI) 3-kinase activation, which leads to Akt activation without stimulating AMP-activated protein kinase (AMPK) (36). A great deal of evidence suggests that contraction stimulates glucose transport by a mechanism independent of PI 3-kinase/Akt (710) and attributable to the effects of multiple inputs, with AMPK- and calcium-mediated processes being major factors (11,12).In 3T3-L1 adipocytes, insulin stimulates phosphorylation of Akt substrate of 160 kDa (AS160; also called TBC1D4) in an Akt-dependent manner on sites identifiable by the phospho-Akt substrate (PAS) antibody (13,14). AS160 includes a Rab GTPase-activating protein domain (RabGAP) that inhibits Rab proteins involved in regulating vesicular traffic (15). The insulin-mediated increase in PAS phosphorylation of AS160 (PAS-AS160) appears to inhibit RabGAP activity, thereby allowing GLUT4 to be recruited to surface membranes and elevate glucose transport (1417). In skeletal muscle, insulin or contraction results in elevated PAS-AS160 (18,19), and AS160 phosphorylation appears to regulate glucose transport (20).Recently, TBC1D1, a RabGAP protein paralog to AS160, was also shown to become PAS-phosphorylated (PAS-TBC1D1) in response to insulin in an Akt-dependent manner (21). However, whereas AS160 knockdown in 3T3-L1 adipocytes resulted in elevated basal cell-surface GLUT4 (17,22), TBC1D1 knockdown had no effect on basal cell-surface GLUT4 in 3T3-L1 cells (23). TBC1D1 protein is only ∼5% as abundant as AS160 protein in 3T3-L1 adipocytes, which may explain why TBC1D1 does not appear to play a major role in regulating glucose transport in these cells (23). TBC1D1 protein abundance is much greater in skeletal muscle versus adipose tissue (24), and silencing TBC1D1 in L6 myotubes resulted in increased basal cell-surface GLUT4 (25), supporting the idea that TBC1D1 inhibits GLUT4 translocation in the basal state. However, in contrast to the results for L6 cells with AS160 knockdown (which did not alter the insulin-stimulated net increase in cell-surface GLUT4), silencing TBC1D1 in L6 cells resulted in greater insulin-induced GLUT4 translocation versus control cells (25). In other words, TBC1D1 knockdown allowed insulin to induce a greater amount of GLUT4 translocation than in cells that express TBC1D1. These findings suggest that at least a portion of the inhibitory effects of TBC1D1 on GLUT4 may not be restrained by insulin. However, they do not eliminate the possibility that TBC1D1 can regulate an insulin-independent increase in glucose transport (e.g., with contraction). PAS-TBC1D1 is elevated in response to contraction in rodent skeletal muscle (19,24). Therefore, it seems possible that PAS-TBC1D1 may play a role in mediating contraction-stimulated glucose transport.Experiments using purified Akt or AMPK demonstrated that each kinase can phosphorylate both AS160 and TBC1D1 in cell-free assays (26,27). Considerable evidence indicates that the insulin-stimulated increase in PAS-AS160 is Akt dependent in skeletal muscle (18,28), and increased AS160 phosphorylation appears to be important for the full effect of insulin on glucose transport (20). However, the specific kinases responsible for contraction-stimulated PAS-AS160 need to be clarified because: 1) Wortmannin can completely inhibit the contraction-stimulated increase in PAS-AS160 in rat skeletal muscle, suggesting that Akt is responsible for the increased PAS-phosphorylation of AS160 during contraction (18), but 2) muscles from mice with genetically disrupted AMPK versus wild-type littermates had reduced contraction-stimulated increase in immunoreactivity toward PAS antibody at ∼160 kDa (PAS-160) (28,29).The primary aim of this study was to elucidate the contributions of Akt and AMPK on increases in PAS-AS160 and PAS-TBC1D1 in skeletal muscle stimulated by insulin or contraction. The PI 3-kinase inhibitor Wortmannin was used to prevent Akt activation (without altering AMPK activation), and compound C, a potent AMPK inhibitor (30), was used to prevent AMPK activation (without altering Akt activation). A secondary aim was to determine whether inhibition of insulin- or contraction-stimulated increases in PAS-AS160 or PAS-TBC1D1 was accompanied by attenuated insulin- or contraction-stimulated glucose transport. We hypothesized that in isolated rat epitrochlearis muscle: 1) Akt-dependent mechanisms are essential for the insulin-stimulated increases in glucose transport and phosphorylation of AS160 and TBC1D1; 2) Akt-dependent (but not AMPK-dependent) mechanisms are essential for contraction-stimulated increases in PAS-AS160, but not glucose transport; and 3) AMPK-dependent (but not Akt-dependent) mechanisms are essential for contraction-stimulated increases in PAS-TBC1D1 (but not PAS-AS160) and glucose transport.  相似文献   
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