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91.
92.
We present a case of cystic meningioma accompanied by hemorrhage in the cyst and adjacent subarachnoid space that occurred while preoperative embolization in feeders of the tumor was being applied. The possible reason for the hemorrhage was the sudden dynamic changes in blood flow triggered by the embolization. The changes could have caused multiple ruptures of pathologic small vessels. We recommend that preoperative embolization should be used cautiously in treating cystic meningiomas because of a possible increase in bleeding from pathologic weak vessels.  相似文献   
93.
BACKGROUND: We investigated heterotopic hepatocyte transplantation on biodegradable polymers as a potential treatment for end-stage liver disease. The primary problem has been insufficient engraftment of transplanted cells partly because of insufficient vascularization. Increasing vascularization through locally delivered angiogenic factors may increase angiogenesis and hepatocyte engraftment. METHODS: We studied the effect of local delivery of basic fibroblast growth factor (bFGF) on angiogenesis and hepatocyte engraftment within tissue-engineered liver constructs. Poly-l-lactic acid discs were fabricated and coated with either a mixture of saline, sucralfate, and Hydron (control group) or bFGF, sucralfate, and Hydron (bFGF group). bFGF release from polymers in vitro was tested using an ELISA. Hepatocytes were isolated from Lewis rats, seeded on control (n=9) or bFGF (n=11) polymers, and implanted into the small bowel mesentery of syngeneic animals. Specimens were harvested after 2 weeks and analyzed for hepatocyte engraftment. Microvascular density was compared between control (n=6) and bFGF groups (n=5). RESULTS: Three hundred twenty-three thousandths of a microgram of bFGF were incorporated per polymer. Greater than 99% of the bFGF was released into solution by 72 hr in vitro. Two weeks after implantation, microvascular density, as measured by capillaries per high-powered field (c/hpf), was significantly greater in the bFGF group (43.8 c/hpf), compared with the control group (30.5 c/hpf; P<0.005). Specimens from the bFGF group (mean engraftment, 61,355 microm2) showed a 2.5-fold increase in hepatocyte engraftment as compared with control (24,197 microm2; P<0.002). CONCLUSIONS: The angiogenic growth factor bFGF can be incorporated into degradable polymers used as delivery devices for hepatocyte transplantation. Implantation of these devices increases angiogenesis into the device and increases hepatocyte engraftment.  相似文献   
94.
BACKGROUND: Postoperative liver failure is a life-threatening complication after hepatic resection. Because of recent advances in liver surgery technique and a more stringent patient selection, mortality after hepatic resection has steadily decreased, but its incidence still ranges from 10% to 20%. The factors linked to postoperative liver failure in major hepatic resection in the modern era should be reevaluated. STUDY DESIGN: Of 80 patients with viral markers (hepatitis C viral antibody or hepatitis B surface antigen) who underwent major hepatic resections (no less than bisegmentectomies) for hepatocellular carcinoma between 1990 and 1996, 7 patients (8.8%) died of postoperative liver failure within 6 months after hepatectomy. The cause of liver failure was analyzed based on both the preoperative data and the intraoperative findings. In addition, since all the patients who died of liver failure underwent a right hepatic lobectomy, a further data analysis was also done in 47 patients who underwent a right lobectomy of the liver. A volumetric analysis by CT was then done to evaluate the remnant liver volume. RESULTS: Between the patients with liver failure and those without liver failure who underwent a right lobectomy, there were no significant differences in preoperative data or intraoperative findings. Volumetric analysis revealed that the remnant liver volume of patients who died of liver failure was significantly smaller than that of patients who lived (p = 0.008). The incidence of liver failure in patients with a remnant liver volume of less than 250 mL/m2 was 7 of 20 (38%), while it was 0 of 27 in patients with a liver volume of no less than 250 mL/m2 (p = 0.0012). The only significant risk factor for liver failure in patients with a remnant liver volume of less than 250 mL/m2 was diabetes mellitus (p = 0.0072). CONCLUSIONS: The expected remnant liver volume appears to be a good predictor for liver failure in patients who undergo a right lobectomy of the liver. In patients with diabetes mellitus and an expected remnant liver volume of less than 250 mL/m2, a major hepatectomy should be avoided. Careful patient selection based on volumetric analysis in major hepatectomy cases could help prevent the occurrence of postoperative liver failure.  相似文献   
95.
96.
Adult T cell leukaemia/lymphoma (ATL) is a human T cell leukaemia virus type‐I (HTLV‐I)‐infected T cell malignancy with poor prognosis. We herein developed a novel therapeutic vaccine designed to augment an HTLV‐I Tax‐specific cytotoxic T lymphocyte (CTL) response that has been implicated in anti‐ATL effects, and conducted a pilot study to investigate its safety and efficacy. Three previously treated ATL patients, classified as intermediate‐ to high‐risk, were subcutaneously administered with the vaccine, consisting of autologous dendritic cells (DCs) pulsed with Tax peptides corresponding to the CTL epitopes. In all patients, the performance status improved after vaccination without severe adverse events, and Tax‐specific CTL responses were observed with peaks at 16–20 weeks. Two patients achieved partial remission in the first 8 weeks, one of whom later achieved complete remission, maintaining their remission status without any additional chemotherapy 24 and 19 months after vaccination, respectively. The third patient, whose tumour cells lacked the ability to express Tax at biopsy, obtained stable disease in the first 8 weeks and later developed slowly progressive disease although additional therapy was not required for 14 months. The clinical outcomes of this pilot study indicate that the Tax peptide‐pulsed DC vaccine is a safe and promising immunotherapy for ATL.  相似文献   
97.
We aimed to investigate the correlation of graft flow measurements between transit-time flow measurement (TTFM) during coronary artery bypass grafting (CABG) surgery and dynamic cardiac CT after the surgery.Fourteen patients underwent CABG with TTFM and postoperative dynamic cardiac CT; 11 internal thoracic artery (ITA) grafts and 15 saphenous venous grafts (SVGs) were included for analysis. Pearsons correlation analysis was performed for the comparisons of the TTFM and cardiac dynamic CT flow parameters.TTFM was not significantly correlated with the CT flow of the ITA grafts (r = −0.23, P = .49), but it had a very strong correlation with the CT flow of the SVGs (r = 0.83, P < .01).In patients who underwent CABG surgery, dynamic cardiac CT enabled quantitative evaluation of SVG flow, with good correlation with TTFM.  相似文献   
98.

Introduction

Abnormal body temperatures (Tb) are frequently seen in patients with severe sepsis. However, the relationship between Tb abnormalities and the severity of disease is not clear. This study investigated the impact of Tb on disease severity and outcomes in patients with severe sepsis.

Methods

We enrolled 624 patients with severe sepsis and grouped them into 6 categories according to their Tb at the time of enrollment. The temperature categories (≤35.5°C, 35.6–36.5°C, 36.6–37.5°C, 37.6–38.5°C, 38.6–39.5°C, ≥39.6°C) were based on the temperature data of the Acute Physiology and Chronic Health Evaluation II (APACHE II) scoring. We compared patient characteristics, physiological data, and mortality between groups.

Results

Patients with Tb of ≤36.5°C had significantly worse sequential organ failure assessment (SOFA) scores when compared with patients with Tb >37.5°C on the day of enrollment. Scores for APACHE II were also higher in patients with Tb ≤35.5°C when compared with patients with Tb >36.5°C. The 28-day and hospital mortality was significantly higher in patients with Tb ≤36.5°C. The difference in mortality rate was especially noticeable when patients with Tb ≤35.5°C were compared with patients who had Tb of >36.5°C. Although mortality did not relate to Tb ranges of ≥37.6°C as compared to reference range of 36.6–37.5°C, relative risk for 28-day mortality was significantly greater in patients with 35.6–36.5°C and ≤35.5°C (odds ratio; 2.032, 3.096, respectively). When patients were divided into groups based on the presence (≤36.5°C, n = 160) or absence (>36.5°C, n = 464) of hypothermia, disseminated intravascular coagulation (DIC) as well as SOFA and APACHE II scores were significantly higher in patients with hypothermia. Patients with hypothermia had significantly higher 28-day and hospital mortality rates than those without hypothermia (38.1% vs. 17.9% and 49.4% vs. 22.6%, respectively). The presence of hypothermia was an independent predictor of 28-day mortality, and the differences between patients with and without hypothermia were observed irrespective of the presence of septic shock.

Conclusions

In patients with severe sepsis, hypothermia (Tb ≤36.5°C) was associated with increased mortality and organ failure, irrespective of the presence of septic shock.

Trial registration

UMIN-CTR ID UMIN000008195  相似文献   
99.
100.
AIM: To examine whether lysophosphatidic acid (LPA) induces phosphorylation of c-Met and epidermal growth factor receptor (EGFR), both of which have been proposed as prognostic markers of colorectal cancer, and whether LPA induces cyclooxygenase-2 (COX-2) expression in human colon cancer cells. METHODS: Using a human colon cancer cell line, LoVo cells, we performed immunoprecipitation analysis, followed by Western blot analysis. We also examined whether LPA induced COX-2 expression, by Western blot analysis. RESULTS: Immunoprecipitation analysis revealed that 10 umol/L LPA induced tyrosine phosphorylation of c-Met and EGFR in LoVo cells within a few minutes. We found that c-Met tyrosine phosphorylation induced by LPA was not attenuated by pertussis toxin or a matrix metalloproteinase inhibitor, in marked contrast to the results for EGFR. In addition, 0.2-40 umol/L LPA induced COX-2 expression in a dose-dependent manner. CONCLUSION: Our results suggest that LPA acts upstream of various receptor tyrosine kinases (RTKs) and COX-2, and thus may act as a potent stimulator of colorectal cancer.  相似文献   
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