Chronological changes in nonhaemorrhagic brain Infarcts with short T1 in the cerebellum and basal ganglia

Our purpose was to investigate nonhaemorrhagic infarcts with a short T1 in the cerebellum and basal ganglia. We carried out repeat MRI on 12 patients with infarcts in the cerebellum or basal ganglia with a short T1. Cerebellar cortical lesions showed high signal on T1-weighted spin-echo images beginning at 2 weeks, which became prominent from 3 weeks to 2 months, and persisted for as long as 14 months after the ictus. The basal ganglia lesions demonstrated slightly high signal from a week after the ictus, which became more intense thereafter. Signal intensity began to fade gradually after 2 months. High signal could be seen at the periphery until 5 months, and then disappeared, while low or isointense signal, seen in the central portion from day 20, persisted thereafter. Received: 1 February 1999 Accepted: 13 September 1999     

Pulmonary fat embolism syndrome: CT findings in six patients

PURPOSE: Our purpose is to describe the CT findings in pulmonary fat embolism syndrome (FES). METHOD: Chest radiographs and CT scans of six patients with pulmonary FES were reviewed. Initial and follow-up CT findings were noted, and the extent of CT abnormalities was correlated with partial pressure of arterial oxygen (PaO2). RESULTS: Focal areas of consolidation or ground-glass opacity and nodules were seen in all patients, predominantly in the upper lobes of the lungs. Association between these opacities and pulmonary vessels was indicated in three patients. In the lower lobes of all patients, gravity-dependent opacities predominated. Diffuse ground-glass opacity was noted in five patients. Follow-up CT scans showed rapid improvement in three patients, but the gravity-dependent opacity progressed. The extent of CT abnormalities correlated positively with PaO2 (r = 0.8, p < 0.05). CONCLUSION: CT findings reflect the pathophysiology of this syndrome, which differs from that of simple capillary permeability pulmonary edema.     

Thallium-201 SPECT with triple-headed gamma camera for differential diagnosis of small pulmonary nodular lesion 20 mm in diameter or smaller

AIM: Although thallium-201 (201Tl) has been used for the diagnosis of lung cancer, its detectability of small pulmonary nodules is not known. The aim of this study was to evaluate the ability of 201Tl SPECT for the differential diagnosis for the pulmonary nodules 20 mm in diameter or smaller. METHODS: 201Tl SPECT was performed in 31 patients suspected of having primary lung cancer. The final diagnosis was established by histology, and tumor size was 10 to 20 mm in diameter. Twenty of 31 patients had malignant tumors, including squamous cell lung cancer (n = 5), adenocarcinoma (n = 14) and small cell lung cancer (n = 1), but in none of them was there mediastinal lymphnode involvement. RESULTS: Ten of 20 malignant tumors and 1 of 11 benign lesions demonstrated significant 201Tl uptake, so that the positive predictive value, negative predictive value, sensitivity and specificity for the diagnosis of lung cancer were 90.9% (10/11), 50.0% (10/20), 50.0% (10/20) and 90.9% (10/11), respectively. CONCLUSION: These data suggest that sensitivity for detecting lung cancer 20 mm or less in diameter may be insufficient, but even in patients with small pulmonary nodules, a positive 201Tl result is highly predictive of lung cancer.     

Surgical Site Infection Following Surgery for Inflammatory Bowel Disease in Patients with Clean-Contaminated Wounds

Background  It is generally believed that the accompanying conditions in patients with inflammatory bowel disease (IBD) are associated with a high incidence of surgical site infection (SSI), and sometimes these patients are classified as compromised hosts without definitive clinical evidence. The aim of this study was to clarify the impact of IBD on the occurrence and features of SSI in patients with clean-contaminated wounds. Methods  We conducted prospective SSI surveillance of 580 patients with clean-contaminated wounds who underwent surgery between March 2006 and December 2007 using the National Nosocomial Infection Surveillance system. Multivariate analyses using stepwise logistic regression were performed to determine risk factors for SSI. Results  A total of 562 patients with clean-contaminated wounds who underwent surgery for IBD [ulcerative colitis (UC), n = 173; Crohn’s disease (CD), n = 122] or colorectal cancer [(CA), n = 267] were identified for evaluation. SSI was observed in 12.6% of all patients and there was no significant difference in infection rate by type of disease (UC, 14.5%; CD, 13.9%; CA, 10.9%). Multivariate logistic regression analysis yielded an ASA score ≥3 [odds ratio (OR) = 2.04; 95% confidence interval (CI) = 1.06–3.93] and rectal surgery (OR = 2.35; 95% CI = 1.28–4.31) as independent risk factors for SSI. IBD surgery was not an independent risk factor for overall SSI (OR = 1.62; 95% CI = 0.94–2.80). However, there was a significant difference in the incidence of incisional SSI [IBD, 11.9% (UC, 12.7%; CD, 10.7%); CA, 4.9%, p = 0.003]. In the analysis of rectal surgery, the incidence of incisional SSI was 5.3% in CA patients, 12.0% in UC patients, and 26.3% in CD patients. In contrast to overall SSI data, IBD surgery was found to be an independent risk factor for incisional SSI (OR = 2.59; 95% CI = 1.34–5.03). Conclusions  In patients of surgery restricted to clean-contaminated wounds, IBD was shown to be an independent risk factor for incisional SSI. With the use of proper operative procedures and techniques, the incidence of organ/space SSI should not be high in patients who undergo an uncomplicated IBD surgical procedure.     

Surgical treatment of thoracic aortic aneurysm in patients with concomitant coronary artery disease

Objective: Surgical treatment of thoracic aortic surgery in patients with coronary artery disease was investigated. Methods: Between 1990 and April 2003, 330 patients underwent elective thoracic aortic surgery. Fifty-six patients who underwent aortic root reconstruction were excluded and 274 patients were examined. Fifty-four (20%) patients showed concomitant coronary artery disease. Ten had undergone coronary revascularization previously; and 3 underwent coronary revascularization [2 coronary artery bypass grafting (CABG), 1 percutaneous transluminal coronary angioplasty (PTCA)] before aortic surgery. Twenty-three patients underwent elective CABG simultaneously and 2 patients had additional coronary artery bypass because of cardiac ischemia during operation. The number of patients who underwent thoracic aortic surgery including Asc Ao+AVR was 2, hemi arch 1, total arch 15, distal arch 5, distal arch+LV aneurysmectomy 1, and thoracoabdominal Ao 1. Two patients underwent coronary revascularization with arterial grafts and the others with SVG grafts. Results: There was one hospital death (4%). In patients without coronary bypass, 2 patients suffered cardiac ischemic events. Conclusion: Our thoracic aortic operations with concomitant CABG using SVG were overall successful. Our current strategies for thoracic aortic surgery in patients with concomitant coronary artery disease include conducting a dipyridamole myocardial perfusion-imaging test first in patients not at risk of coronary artery disease, and if the test is positive, coronary angiography is performed and aggressive coronary revascularization is conducted where possible.     

Late outcomes after isolated coronary artery bypass grafting for ischemic mitral regurgitation

Objectives: Although ischemic mitral regurgitation (IMR) is one of the most important issues to determine therapeutic strategy for ischemic heart disease, long-term outcome after coronary artery bypass grafting (CABG) for IMR is still unclear. It is also controversial how patients who would benefit from mitral valve (MV) surgery in combination with CABG should be identified. The purpose of this study is to elucidate late outcomes after isolated CABG for moderate IMR and to assess the indication of combined MV surgery. Methods: Two hundred and seventy-nine patients who had grade 2 or 3 IMR preoperatively and underwent isolated CABG between 1980 and 2002 in our institute were enrolled. Mitral regurgitation was assessed by 2-dimensional Doppler echocardiography and left ventriculography. Among them, 84 patients (30.1%) had left ventricular ejection fraction (LVEF) less than 30% and 186 patients (66.7%) had prior inferior myocardial infarction (MI). Results: One hundred and twenty-nine patients (46.2%) remained grade 2 or greater MR early postoperatively. Actuarial survival and freedom from cardiac events, analyzed by the Kaplan-Meier method, were 90.9% and 87.7% at 1 year, 79.2% and 68.8% at 5 years, 54.9% and 49.1% at 10 years and 48.8% and 18.9% at 15 years. Independent predictive risk factors for cardiac events, analyzed by multivariate analysis using the Cox proportional hazard model, were grade 2 or greater MR which remained early postoperatively (p=0.0002), LVEF<30% preoperatively (p=0.0006), no inferior MI preoperatively (p=0.007) and no internal thoracic artery-left anterior descending artery graft (p=0.049). More than a 15% decrease in LVEF at more than 3 years after the operation was seen despite patent bypass grafts in 17.2% of patients who received a late follow-up catheterization, although 41.4% of patients showed an increase or less than 5% decrease in LVEF during this period. Conclusion: Combined MV surgery with CABG for IMR should be considered in patients with poor LVEF or without prior inferior MI.     

Stability and repeat regeneration potential of the engineered liver tissues under the kidney capsule in mice

Liver tissue engineering using hepatocyte transplantation has been proposed as a therapeutic alternative to liver transplantation toward several liver diseases. We have previously reported that stable liver tissue with the potential for liver regeneration can be engineered at extrahepatic sites by transplanting mature hepatocytes into an extracellular matrix. The present study was aimed at assessing the liver tissue persistence after induced regeneration by hepatectomy and repeat regeneration potential induced by repeat hepatectomy. Mouse isolated hepatocytes mixed in EHS extracellular matrix gel were transplanted under both kidney capsules of isogenic mice. The hepatocyte survival persisted for over 25 weeks. In some of the mice, we confirmed that the grafted hepatocytes developed a thin layer of liver tissues under the kidney capsule, determined by specific characteristics of differentiated hepatocytes in cord structures between the capillaries. We then assessed the regenerative potential and persistence of the exogenous liver tissue. To induce liver regeneration, we performed a two-thirds hepatectomy at 70 days after hepatocyte transplantation. Three weeks after this procedure, the engineered liver tissues showed active regeneration, reaching serum marker protein levels of 261 +/- 42% of the prehepatectomy level. We found that the regenerated liver tissue was stably maintained for 100 days (length of the experiment). Repeat regeneration potential was established by performing a repeat hepatectomy (that had been two-thirds hepatectomized at day 70) 60 days after the initial hepatectomy. Again, the regenerated engineered liver tissues showed active regeneration as there was an approximately twofold increase in the serum marker protein levels. The present studies demonstrate that liver tissue, which was recognized as a part of the host naive liver in terms of the regeneration profile, could be engineered at a heterologous site that does not have access to the portal circulation.     

Lack of correlation between results of ABO-incompatible living kidney transplantation and anti-ABO blood type antibody titers under our current immunosuppression

In this study, we examined the impact of preoperative anti-A/B antibody titers on the results of ABO-incompatible living kidney transplantation (LKT). In all, 167 recipients underwent ABO-incompatible LKT at our institution between 1989 and 2002. These patients were subdivided into those transplanted under cyclosporine with azathioprine or mizoribine (Group 1, n=78) and those transplanted under tacrolimus or mycophenolate mofetil (Group 2, n=89). Overall patient survival at 5 and 10 years was 93.8% and 88.0%, respectively. Overall graft survival at 5 and 10 years was 76.9% and 55.9%, respectively. Graft survival in the patients with anti-A/B IgG titers over 1:128 was significantly lower in group 1, whereas no significant correlation between the anti-A/B IgG titers and graft survival was found in group 2. In conclusion, no correlation between anti-A/B antibody titers and the results of ABO-incompatible LKT was seen after tacrolimus or mycophenolate mofetil application.     

Analysis of risk factors for the development of gallstones after gastrectomy

BACKGROUND: The incidence of gallstones is higher in people who have undergone gastrectomy than in the general population, but the cause of this is unknown. METHODS: Between January 1992 and January 2003, 749 patients underwent ultrasonography of the gallbladder after gastrectomy for gastric cancer. A total of 2327 examinations were carried out. The incidence of gallstones was compared in subgroups of patients classified according to the type of reconstruction, extent of gastrectomy, whether the duodenum was excluded and type of lymph node dissection. RESULTS: The incidence of gallstones was significantly higher after total compared with partial gastrectomy (27.9 versus 7.8 per cent at 5 years; P < 0.001). Reconstruction with duodenal exclusion was associated with a significantly higher incidence than non-exclusion (25.1 versus 8.2 per cent at 5 years; P < 0.001). Patients who had lymph node dissection in the hepatoduodenal ligament had a significantly higher incidence of gallstones than those who did not (28.2 versus 7.5 per cent at 5 years; P < 0.001). In multivariate analysis that included type of reconstruction and lymph node dissection, lymph node dissection in the hepatoduodenal ligament was identified as the most significant risk factor for gallstone development (odds ratio 3.66 (95 per cent confidence interval 2.16 to 6.22); P < 0.001). CONCLUSION: Lymph node dissection in the hepatoduodenal ligament, total gastrectomy and exclusion of the duodenum are risk factors for gallstones after gastrectomy.     

Function of the vascular endothelial growth factor receptors Flt-1 and Flk-1/KDR in the alloimmune response in vivo

BACKGROUND: We have recently reported that vascular endothelial growth factor (VEGF) functions as a proinflammatory cytokine to regulate the trafficking of leukocytes into allografts in the early posttransplant period. VEGF binds two major VEGF receptors: VEGFR-1 (flt-1) and VEGFR-2 (flk-1/KDR). Here, we wished to investigate the expression and function of VEGF receptors in the process of acute allograft rejection in vivo. METHODS: We performed fully MHC-mismatched C57BL/6 (H-2b) into BALB/c (H-2d) vascularized heterotopic murine cardiac transplants and we examined the expression of VEGF and VEGF receptors by immunohistochemistry during acute allograft rejection. Next, we treated mice with specific neutralizing monoclonal antibodies against murine VEGFR-1 and VEGFR-2 and examined their effect on the development of acute allograft rejection by histology and by analysis of graft survival. The intragraft expression of cytokines and chemokines were also evaluated by quantitative real-time PCR analysis. RESULTS: The expression of VEGF, VEGFR-1 and VEGFR-2 were significantly up-regulated during allograft rejection as compared to isografts. Administration of either anti-VEGFR-1 or anti-VEGFR-2 alone failed to inhibit allograft rejection. However, coadministration of both antibodies together inhibited leukocyte infiltration of allografts and prolonged allograft survival. Furthermore, the effect of VEGFR blockade was associated with the downregulation of intragraft cytokine and chemokine expression. CONCLUSIONS: Our data suggest that VEGF-VEGFR interactions function in the alloimmune response in vivo. Targeting VEGFRs may represent a novel therapy to protect allografts following clinical transplantation.