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71.
BACKGROUND: Flush perfusion with low-potassium dextran is the standard strategy in clinical lung preservation. Despite improved outcome, endothelial cell injury and surfactant dysfunction remain a significant problem after lung transplantation. The radical scavenger glutathione has been shown to be responsible for the efficacy of Celsior solution in lung preservation. We tested the hypothesis that the addition of glutathione to low-potassium dextran might further improve graft function by ameliorating ischemia-reperfusion injury. METHODS: In 12 domestic pigs, lungs were flush preserved with either low-potassium dextran (n = 6) or low-potassium dextran supplemented by 5 mmol glutathione (n = 6). Left single lung transplantation was performed after 24-hour storage in low-potassium dextran at 8 degrees C. After 15 minutes of reperfusion the right main bronchus and pulmonary artery were crossclamped. Hemodynamic and respiratory measures were recorded in 30-minute intervals for a total observation period of 7 hours. Bronchoalveolar lavage fluid was obtained from the native lung and 2 hours after reperfusion from the graft. Bronchoalveolar lavage fluid and surfactant composition, and surfactant function analyses were performed. Neutrophil sequestration was assessed by myeloperoxidase activity assay. Tissue water content was calculated from wet/dry weight ratios at the end of the experiment. RESULTS: In the low-potassium dextran group, 2 animals died during reperfusion. After reperfusion, pulmonary vascular resistance (P = .01) and pulmonary artery pressure remained lower in the glutathione/low-potassium dextran group, which was associated with a higher cardiac output (P = .05) in this group. Also, the oxygenation index at the end of the observation period was higher in the glutathione/low-potassium dextran group compared with the low-potassium dextran group (430 +/- 130 vs 338 +/- 184, respectively; P < .05). The graft water content representing postreperfusion lung edema was not different between the 2 study groups. Alteration of surfactant was less in the glutathione/low-potassium dextran group with a significantly decreased small to large aggregate ratio (P = .03) versus low-potassium dextran group. Myeloperoxidase activity was twice as high in the low-potassium dextran group when compared with the glutathione/low-potassium dextran group (glutathione/low-potassium dextran: 134 +/- 110 mU/g vs low-potassium dextran: 274 +/- 168 mU/g, P = .07). CONCLUSION: The addition of glutathione to low-potassium dextran preservation solution reveals beneficial effects on vascular function and surfactant composition in transplanted lungs. Therefore, glutathione ameliorates ischemia-reperfusion injury in a preclinical model of lung transplantation. Future studies are needed to evaluate this promising modification in clinical lung transplantation.  相似文献   
72.
OBJECTIVE: Condylus occipitalis is presented in postmortem anatomic studies. There is no clinical study in the literature. Myelopathy due to anomalies of the craniovertebral junction is rare in neurosurgical practices. To our knowledge, myelopathy due to condylus occipitalis has not been reported before. Deaths of two cases were previously reported, but these were not live cases. METHODS: We describe the case of a 40-year-old woman presenting with progressive myelopathy related to condylus occipitalis located in the anterior foramen magnum region. RESULTS: Magnetic resonance imaging and computed tomography showed the condylus occipitalis, marked stenosis of the spinal canal at the level of the atlas, with cord compression and evidence of myelopathy. We performed posterior decompression without fusion and duraplasty. Because the cervicomedullary compression syndrome was not resolved, a transoral decompression could not be done owing to pulmonary insufficiency. CONCLUSIONS: This unique clinical article (a live case), not anatomic, presents a very rare abnormality of the craniovertebral junction. Myelopathy is a very important complication of this congenital craniovertebral junction abnormality. Posterior decompression seems not to be effective for myelopathy due to condylus occipitalis. In our opinion, anterior decompression is needed in this condition. A larger series will be needed to better define its role in the management of this anomaly.  相似文献   
73.
Purpose Intraperitoneal chemotherapy (IPCT) delivers higher local concentrations of cytotoxic drugs than intravenous (IV) chemotherapy, but it can adversely affect the healing of intestinal anastomoses if given in the early postoperative period. Intestinal anastomotic leakage is a serious surgical complication. Experimental and clinical studies have shown that the local administration of granulocyte macrophage-colony stimulating factor (GM-CSF) improves would healing. Therefore, we evaluated the effects of locally applied GM-CSF on anastomotic wound healing in rats treated with intraperitoneal mitomycin-C immediately after surgery.Methods We performed colon anastomoses in albino rats, which were then divided into three treatment groups. Group A was a control group that received no treatment, Group B was given intraperitoneal mitomycin-C postoperatively, and Group C was given intraperitoneal mitomycin-C with a local injection of GM-CSF postoperatively. We measured bursting pressures and hydroxyproline content, and histologically examined the resected anastomoses on postoperative day (POD) 3.Results Anastomotic healing was impaired after intraperitoneal mitomycin-C, but this was overcome by the injection of GM-CSF into the perianastomotic area.Conclusion Local GM-CSF administration counteracts the detrimental effects of intraperitoneal mitomycin-C treatment on intestinal anastomoses in rats.  相似文献   
74.
75.
BACKGROUND: Early diagnosis of mesenteric ischemia can be life saving. The aim of this study is to investigate the time-dependent diagnostic value of plasma D-dimer and other ancillary laboratory evaluations such as creatine phosphokinase, lactic dehydrogenase, aspartate aminotransferase, alanine aminotransferase, amylase, and leukocyte count in an experimental superior mesenteric arterial occlusion (SMA-O) model in rats. METHODS: Forty male Wistar-Albino rats were separated into 4 groups: 2-, 4-, 6-, and 12-hour SMA-O groups. After laparotomy, the SMA was identified and ligated for 2, 4, 6 and 12 h in the 4 respective study groups. Blood samples were taken for laboratory tests 2 h after laparotomy in the control group and at the end of the ischemic period in the study groups. RESULTS: The longer the duration of mesenteric ischemia, the higher were the serum D-dimer levels in the study groups, and statistical significance was obtained at 2 h (p = 0.021). Sensitivity, positive predictive value, negative predictive value, and accuracy of the relation were 88.8, 88.8, 100 and 90%, respectively. Leukocyte count was significantly higher than controls after 12 h. No other laboratory parameter correlated positively with the duration of mesenteric ischemia. CONCLUSION: Serum D-dimer measurements may be a valuable diagnostic parameter in the early diagnosis of mesenteric ischemia.  相似文献   
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77.
OBJECTIVE: The aim of the present study was to document the serum IL-18 levels in patients with pulmonary tuberculosis (P-TB), extrapulmonary tuberculosis (EP-TB), pneumonia, lung cancer and in healthy controls, and to investigate whether it may assist in the differential diagnosis of P-TB. METHODOLOGY: A total of 116 patients were included in the study. The study population consisted of patients with P-TB, EP-TB, pneumonia and lung cancer and controls. P-TB patients were graded according to sputum positivity and extent of disease. Serum levels of IL-18 (ELISA) were compared between groups and with other clinical measures of disease. RESULTS: Compared with the controls, all groups of patients had increased serum levels of IL-18. The highest mean concentration of IL-18 was observed in P-TB. Serum levels of IL-18 in the patients with P-TB correlated well with the extent of disease. CONCLUSIONS: Although increased serum levels of IL-18 were not specific for TB, the increased levels may favour active TB in radiologically advanced disease where CXR findings are difficult to interpret, and sputum smears or cultures are not helpful.  相似文献   
78.
Reactive oxygen species play a role during brain injury due to closed head trauma. Enzymatic or nonenzymatic antioxidants may protect brain tissue against oxidative damage. The present study was performed to assess the changes of endogenous indices of oxidative stress in serum from rats subjected to head trauma and whether treatment with propofol and/or erythropoietin (EPO) modifies the levels of endogenous indices of oxidative stress. For these purposes, female Wistar Albino rats were divided into five groups: non-traumatic sham group, trauma performed control, trauma with propofol (i.p.), trauma with EPO (i.p.) and trauma with propofol and EPO performed study groups. At the end of the experimental procedure, blood was taken by cardiac puncture to determine superoxide dismutase (SOD) and xanthine oxidase (XO) activities as well as malondialdehyde (MDA) and nitric oxide (NO) levels in serum. Serum MDA level of control traumatic brain injury (TBI) group was significantly higher than sham operation group (p<0.012). Serum MDA levels in propofol, EPO and propofol+EPO groups were found to be decreased in comparison with control group (p<0.039, p<0.030 and p<0.018, respectively). Serum NO level was found to be increased in TBI group, but difference was not statistically significant when compared to sham-operated group (p=0.092). Propofol, EPO and propofol+EPO administration efficiently reduced serum NO levels to reach sham-operated group (p<0.002, p<0.001 and p<0.015, respectively). These results suggested that acute administration of both propofol and EPO altered the indices of oxidative stress similarly against brain injury due to trauma.  相似文献   
79.
An 18-year-old female patient suffering from a painful right-sided neck mass was admitted to our emergency service. Computed tomography of the neck revealed thrombosis of the right internal jugular vein. Computed tomography of the chest indicated septic pulmonary emboli in both lungs. Blood and oropharyngeal cultures showed proteus that was sensitive to cefepime and amicasin. Chemotherapy was administered for 12 days, however, her complaints continued with fulminant progression. An urgent decompression and excessive debridement were performed. Although Lemierre syndrome is a well-known cause of internal jugular vein thrombosis, association with proteus culture is very rare.  相似文献   
80.
Purpose To determine the optimal timing of surgery after adriamycin treatment, we investigated the time-related effect of adriamycin on wound healing over a long period.Methods We divided 119 female Sprague-Dawley rats into seven treatment groups. Group 1 was subjected to laparatomy only. All the other groups were given 8mg/kg adriamycin intravenously followed by laparotomy on the same day (group 2), 7 days later (group 3), 14 days later (group 4), 21 days later (group 5), 28 days later (group 6), or 35 days later (group 7). On postoperative day 7, the sutures were removed, abdominal bursting pressure was measured, and tissue samples were taken for histopathological evaluation and analysis of hydro-xyproline content.Results Bursting pressures were significantly lower in groups 3, 4, 5, and 6 than in group 1. The hydroxyproline content and histopathological evaluation supported these findings.Conclusions Our results showed that the optimal timing for surgery after adriamycin treatment is before the 7th day or after the 35th day. If surgery is performed between these days, there is a high risk of impaired wound healing.A preliminary study on this subject was accepted as a poster presentation at the Congress of the European Surgical Society of Oncology (ESSO) in 2002  相似文献   
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