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91.
We report an 18-month-old boy with the association of pectus excavatum and tetralogy of Fallot (TOF). We successfully performed simultaneous pectus repair using sternal elevation without any prosthetic support and total correction of TOF after a prior modified Blalock-Taussig shunt. Retracting a divided costo-sternal complex with a rectus abdominal flap away from the operative field before the cardiac operation provided excellent surgical exposure. The modified Blalock-Taussig shunt prior to the combined repair prevented life-threatening hypoxic spells during dissection of the deformed sternum and costochondral cartilages before institution of cardiopulmonary bypass.  相似文献   
92.
Several reports claim that portal hypertension after living-donor liver transplantation (LDLT) adversely affects graft function, but few have assessed the impact of portal venous pressure (PVP) on graft regeneration. We divided 32 adult LDLT recipients based on mean PVP during the 1st 3 days after LDLT into a group with a PVP > or = 20 mm of Hg (H Group; n = 17), and a group with a PVP < 20 mm of Hg (L Group; n = 15). Outcome in the H Group was poorer than in the L Group (58.8 vs. 92.9% at 1 year). Peak peripheral hepatocyte growth factor (HGF) during the 1st 2 weeks was higher in the H Group (L: 1,730 pg/mL, H: 3,696 pg/mL; P < .01), whereas peak portal vascular endothelial growth factor (VEGF) level during the 1st week was higher in the L Group (L: 433 pg/mL, H: 92 pg/mL; P < .05). Graft volume (GV) / standard liver volume (SLV) was higher in the H Group (L / H, at 2, 3, and 4 weeks, and at 3 months: 1.02 / 1.24, .916 / 1.16, .98 / 1.27, and .94 / 1.29, respectively; P < .05). Peak serum aspartate aminotransferase, bilirubin levels, and international normalized ratio after LDLT were significantly higher in the H Group, as was mean ascitic fluid volume. In conclusion, early postoperative PVP elevation to 20 mm of Hg or more was associated with rapid graft hypertrophy, higher peripheral blood HGF levels, and lower portal VEGF levels; and with a poor outcome, graft dysfunction with hyperbilirubinemia, coagulopathy, and severe ascites. Adequate liver regeneration requires an adequate increase in portal venous pressure and flow reflected by clearance of HGF and elevated VEGF levels.  相似文献   
93.
We examined the effects of a new inotrope, OPC-8212 (OPC: 2(1H)-quinolinone), on coronary sinus flow (CSF), myocardial oxygen consumption, myocardial lactate extraction ratio (LER), cardiac index (CI) and pulmonary arterial diastolic pressure (PADP) in eleven patients with prior myocardial infarction. Measurements were taken before (control) and 8 hours after administration of OPC (480 mg, p.o.). A cardiac function curve was obtained in each stage with rapid intravenous administration of 500 ml of saline (loaded state) after baseline measurements. There was a significant increase in the cardiac index and decrease in the pulmonary arterial diastolic pressure in the loaded state after OPC. Thus the ventricular function curve was shifted to the left and showed a steep incline, indicating an increased inotropic state. On the other hand, myocardial oxygen consumption and myocardial lactate extraction ratio were unchanged. Thus we concluded that OPC improved cardiac performance without increasing myocardial oxygen consumption.  相似文献   
94.
The carcinogenic activity of endogenously synthesized N-nitrosobis(2-hydroxypropyl)amine(BHP) was investigated in male Wistar rats administered bis(2-hydroxypropyl)amine(BHPA) mixed in powder diet at a concentration of 1%, and sodiumnitrite (SN) dissolved in distilled water at concentrationsof 0.15 and 0.3%, for 94 weeks. Urinary excretion of BHP wasdetected in rats given 1% BHPA and 0.3% SN but not in the groupsreceiving either of these precursors alone. Nasal cavity, lung,esophagus, liver and urinary bladder tumors were found in animalstreated with combinations of 1% BHPA and 0.15 or 0.3% SN, suggestingthat the target organs of the endogenously synthesized BHP aresimilar to those affected when the carcinogen is administeredexogenously. The incidences of nasal cavity and lung tumorsreached 74 and 58% in rats given 1% BHPA and 0.3% SN, respectively.Tumors at sites other than target organs were only found atlevels similar to those previously reported for spontaneoustumors in male Wistars. The present results clearly indicatedthe tumor inducibility of a nhrosatable amine, BHA, throughan endogenous nitrosation by feeding to rats in conjunctionwith nitrite, and provide further suggestive evidence that endogenousnitrosations of environmental nitrosatable amines can be a potentialrisk factor in human cancer development.  相似文献   
95.
Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) protein levels increase in particulate fractions in association with cell death in HEK293 cells, S49 cells, primary thymocytes, PC12 cells, and primary cerebral cortical neuronal cultures. Subcellular fractionation and immunocytochemistry reveal that this increase primarily reflects nuclear translocation. Nuclear GAPDH is tightly bound, resisting extraction by DNase or salt treatment. Treating primary thymocytes, PC12 cells, and primary cortical neurons with antisense but not sense oligonucleotides to GAPDH prevents cell death. Because cell-death-associated nuclear translocation of GAPDH and antisense protection occur in multiple neuronal and nonneuronal systems, we propose that GAPDH is a general mediator of cell death and uses nuclear translocation as a signaling mechanism.  相似文献   
96.
We have previously shown that interleukin (IL)-1beta and tumour necrosis factor (TNF)-alpha mRNA levels in rat alveolar macrophages are increased in by endotoxin (lipopolysaccharide; LPS)- stimulation and further enhanced by culturing with low-Mg2+ medium. We have now investigated the mechanisms of underlying this enhancement by using some specific signal transduction inhibitors. The enhanced elevation of both mRNAs levels was suppressed by pretreatment with TMB-8 (which inhibits calcium release from the endoplasmic reticulum) or dexamethasone (which inhibits nuclear factor [NF]-kappaB and activator protein [AP]-1), but not with verapamil or nifedipine (which inhibits calcium channels). The enhancment of IL-1beta, but not TNF-alpha mRNA levels, was suppressed by pretreatment with W-7 (which inhibits calmodulin), whereas the enhancement of TNF-alpha mRNA levels was suppressed by pretreatment with U73122 (which inhibits phospholipase C). Curcumin (an inhibitor of AP-1), suppressed the increases in both mRNAs induced by low-Mg2+ medium alone, but had no suppressive effect on the levels of either mRNA after LPS-stimulation in low-Mg2+ medium. Pyrrolidine dithiocarbamate (an inhibitor of NF-kappaB) prevented the elevation of TNF-alpha mRNA levels induced by low-Mg2+ medium without LPS-stimulation, but had no suppressive effect on IL-1beta mRNA levels. From these results, we conclude that the enhanced elevation of IL-1beta and TNF-alpha mRNA levels seen in LPS-stimulated alveolar macrophages in low-Mg2+ medium occurs partly via the same, and partly via different, signaling pathways.  相似文献   
97.
Lymphoblastic lymphoma, an aggressive mediastinal mass, is recognized as serious threat to the patient in developing cardiac tamponade or airway obstruction. Surgical procedure is often required to relieve clinical emergency and to establish prompt pathological diagnosis. However, in such a patient, acute respiratory occlusion in the spine position can be a life-threatening complication during general anesthesia. We describe a 17-year-old man whose cardiac tamponade was treated by pericardial-pleural window through a left anterior thoracotomy in the lateral position. The patient recovered from hemodynamic compromise without showing respiratory occlusion during general anesthesia and remained in the lateral position until extubation. Pathological diagnosis was precursor T-lymphoblastic lymphoma. There were no complications attributable to the operative procedure. Further chemotherapy reduced the mediastinal mass in size after two weeks when the patient developed sepsis and died. Lateral position prevents respiratory occlusion during surgical procedure under general anesthesia in the patient of huge anterior mediastinal tumor with airway obstruction.  相似文献   
98.
Plasma carnitine concentrations in patients undergoing open heart surgery.   总被引:3,自引:0,他引:3  
Carnitine is an essential cofactor for fatty acid (FA) metabolism, the predominant source of ATP in the normal aerobic heart. During myocardial ischemia, FA metabolism is impaired and tissue carnitine levels are depleted. Since the heart cannot synthesize carnitine, plasma carnitine could play an important role in maintaining myocardial carnitine levels during reperfusion. The purpose of this study was to determine the incidence of abnormal plasma carnitine concentrations in open heart surgery. Blood samples were obtained from eleven patients before, immediately after, and two hours after cardiopulmonary bypass (CPB). Total and free carnitine levels were significantly reduced immediately after CPB (p<0.01) and remained depressed until two hours after CPB (p<0.01 vs. pre CPB), while acyl carnitine levels were unchanged over the course of this study. These depressed free carnitine levels might affect cardiac metabolism in the heart after open heart surgery. Carnitine supplement might be a useful adjunct in the therapy after open heart surgery.  相似文献   
99.
A 52 year-old woman noticed general fatigue, polyarthralgia, and muscle weakness of lower extremities in October 2001. In December, she felt difficulty in walking due to muscle weakness. In January 2002, she admitted another hospital because of dyspnea on exertion and edema of lower extremities. Laboratory test revealed leukocytopenia, the elevation of creatine kinase and positive anti-U1-RNP antibodies. Her chest computed tomography (CT) showed severe interstitial pneumonia. Cardiac echogram revealed that she had pericardial effusion and pulmonary hypertension. Then she was transferred to Keio University Hospital and she was diagnosed as having mixed connective tissue disease (MCTD) manifestating myositis, interstitial pneumonia, pulmonary hypertension and pericarditis. Prednisolone (PSL) 60mg daily following to methylprednisolone (mPSL) pulse therapy was begun and her symptoms were gradually improved. In middle of February, she complained of high fever over 39.0 degrees C. Bacterial culture tests were negative and laboratory data indicated pancytopenia and a high level of serum ferritin. Bone marrow aspiration revealed hemophagocytosis in bone marrow specimens and she was diagnosed as having hemophagocytic syndrome associated with MCTD. mPSL pulse therapy was not effective and intermittent cyclophosphamide pulse therapy (IV-CY) was performed resulting in improvement of the symptoms. This case suggested the effectiveness of IV-CY therapy in patients with corticosteroid-resistant HPS associated with connective tissue diseases.  相似文献   
100.
PURPOSE: This study investigated the effect of parathyroid hormone (1-34) [PTH(1-34)] on bone reactions after tibial placement of titanium screw implants into ovariectomized rats. MATERIALS AND METHODS: Twelve-week-old female Wistar rats were divided into 3 groups of 24. The first group (Sham group) was sham-operated; the second group (OVX group) was ovariectomized only; and the third group (PTH group) was subcutaneously administered 30 microg/kg PTH in the dorsal region 3 days per week starting the fourth week after ovariectomy until the end of the experiment. Titanium screw implants were placed in the proximal metaphysis of the tibia of all 3 groups at 168 days after surgery. The animals were killed 7, 14, 28, and 56 days after implantation. Undecalcified sections were prepared and evaluated by light microscopy. Histomorphometric measurements were obtained using a computer-based image analyzer to quantify the unit bone mass around the implant and the rate of implant-bone contact. RESULTS: When PTH administration was started 21 days after ovariectomy, the volume density of bone around implants in the PTH group was almost the same as that of the Sham group throughout the entire observation period. This finding suggests that not only can intermittent human PTH(1-34) administration prevent resorption of newly generated trabeculae around an implant but also it can aid in the recovery of bone volume lost due to ovariectomy. CONCLUSION: When dental implants are applied to jaw bone showing trabecular bone loss, it may be possible to increase bone density around an implant by intermittent human PTH(1-34) administration and thereby improve clinical results.  相似文献   
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