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941.
BACKGROUND: Despite recent improvements in the treatments of coronary artery disease (CAD), there are a considerable number of patients who can not receive complete revascularization because of severe or total arterial occlusion. Intramyocardial injection of autologous bone marrow mononuclear cells (ABMMCs) has been shown to induce neovascularization of ischemic myocardium. METHODS AND RESULTS: The study will investigate the safety and feasibility of intramyocardial injections of ABMMCs and test the hypothesis that this treatment would promote neovascularization and improve left ventricular (LV) global and/or regional function in patients with severe CAD who have no other option. ABMMCs (approximately 10(6) cells) will be injected into the area of ischemic myocardium where the coronary artery is not graftable, in combination with bypass surgery to the other coronary branches. Myocardial perfusion and LV global and regional function will be evaluated, based on the micromanometer-tipped catheter method, single-photon emission tomography, and myocardial enhanced and color tissue Doppler echocardiography at baseline and during 12 month follow-up. CONCLUSIONS: This project will demonstrate that intramyocardial injection of ABMMCs with or without coronary artery bypass surgery could be a safe and effective method for therapeutic neovascularization, resulting in an improvement of cardiac function in patients with severe CAD.  相似文献   
942.
BACKGROUND: Multislice computed tomography (MSCT) was used to evaluate coronary artery remodeling in patients with acute coronary syndrome (ACS) and stable angina (SA). METHODS AND RESULTS: MSCT was performed in 31 patients with ACS and 26 patients with SA and intravascular ultrasound (IVUS) was performed in 28 of these 57 patients. In both the MSCT and IVUS analyses, coronary artery remodeling was assessed by the remodeling index (RI): RI >1.10 was defined as positive coronary artery remodeling (PCAR) and RI <0.95 was defined as negative coronary artery remodeling (NCAR). The RI assessed by MSCT closely correlated with that of IVUS (r=0.86, n=28). The vessel area at the region of maximum luminal narrowing was also comparable between the MSCT and IVUS measurements (r=0.92). PCAR was present in 19 patients (61.3%) with ACS, but in none of the patients with SA (p<0.0001). However, NCAR was present in only 1 patient with ACS (3.2%), but was present in 18 patients (62.9%) with SA. The RI was significantly larger in patients with ACS (1.19+/-0.18) than in those with SA (0.89+/-0.10, p<0.0001). CONCLUSION: MSCT accurately assesses coronary artery remodeling.  相似文献   
943.
Role of ischemia in acute pancreatitis   总被引:27,自引:0,他引:27  
Ischemia has been considered to play a role in the development of acute pancreatitis. The aim of this study was to investigate the effect of ischemia, caused by hemorrhagic shock, on cerulein-induced acute pancreatitis in rats. Acute pancreatitis was induced by the intravenous infusion of a supramaximally stimulating dose of cerulein (10 g/kg/hr) for 6 hr. Hemorrhagic shock was induced by the removal of blood until the mean arterial blood pressure reached 35 mm Hg. This level was maintained for 30 min, after which time all the blood was reinfused. Hemorrhagic shock alone induced no morphological change in the pancreas. However, after the induction of hemorrhagic shock in animals treated with cerulein, hemorrhage and parenchymal necrosis were frequently observed in the pancreas. Seven of 20 rats (35%) receiving cerulein plus hemorrhagic shock had died by 48 hr after the start of cerulein infusion, whereas none of the rats in the cerulein or shock group died during this experiment. Cathepsin B activity in the pancreas of the cerulein plus shock group was significantly higher than in the other groups at 48 hr. These results suggest that ischemia may be a contributing factor in the pathogenesis of acute pancreatitis.This study was supported by a grant, Scientific Research B-03454319, from the Ministry of Education, Science and Culture, and a grant from the Ministry of Health and Welfare of Japan  相似文献   
944.

Background

Trinitrobenzenesulfonic acid (TNBS)-induced colitis is one of the most widely used experimental colitis models. However, there is no standard procedure for inducing colitis by TNBS because it is difficult to achieve a uniform distribution of colitis. We have developed a modified method of murine TNBS-induced colitis that involves inhalation anesthesia with sevoflurane combined with both single and repeated TNBS administrations.

Aims

To compare the usefulness of our newly developed method for inducing murine TNBS-induced colitis with that of conventional intraperitoneal anesthesia.

Methods

TNBS in ethanol was administered to C57BL/6J mice held in an inverted vertical position either under continuous inhalation anesthesia with sevoflurane, in accordance with our newly developed method, or by intraperitoneal injection with 2.5 % avertin, in accordance with the conventional procedure. Body weight change, cytokine profile, and histological findings were examined during the course of colitis.

Results

The dispersion of anesthesia time, TNBS retention time, and nadir weight during the course of colitis was decreased using the newly developed method compared with the conventional procedure. Optimization of the modified TNBS-induced colitis, as evidenced by the predominant expression of Th1 and Th17 cytokines on day 7, was attained by the injection of 2.25 mg TNBS in 55 % ethanol. Regulation of the TNBS retention time using inhalation anesthesia with sevoflurane allowed strict control of the disease severity of TNBS-induced colitis. Using the modified method we were also able to develop a chronic TNBS-induced colitis model by repeated TNBS administration without excessive mortality of the mice.

Conclusions

Our modified method for murine TNBS-induced colitis using continuous inhalation anesthesia with sevoflurane provides a better experimental colitis model following both single and repeated TNBS administrations.  相似文献   
945.
Proteus mirabilis ARS68, which demonstrated a very high level of resistance to various aminoglycosides, was isolated in 2003 from an inpatient in Japan. The aminoglycoside resistance of this strain could not be transferred to recipient strains Escherichia coli CSH-2 and E. coli HB101 by a general conjugation experiment, but E. coli DH5alpha was successfully transformed by electroporation with the plasmid of the parent strain, ARS68, and acquired an unusually high degree of resistance against aminoglycosides. Cloning and sequencing analyses revealed that the presence of a novel 16S rRNA methylase gene, designated rmtC, was responsible for resistance in strain ARS68 and its transformant. The G+C content of rmtC was 41.1%, and the deduced amino acid sequences of the newly identified 16S rRNA methylase, RmtC, shared a relatively low level of identity (< or = 29%) to other plasmid-mediated 16S rRNA methylases, RmtA, RmtB, and ArmA, which have also been identified in pathogenic gram-negative bacilli. Also, RmtC shared a low level of identity (< or = 28%) with the other 16S rRNA methylases found in aminoglycoside-producing actinomycetes. The purified histidine-tagged RmtC clearly showed methyltransferase activity against E. coli 16S rRNA in vitro. rmtC was located downstream of an ISEcp1-like element containing tnpA. Several plasmid-mediated 16S rRNA methylases have been identified in pathogenic gram-negative bacilli belonging to the family Enterobacteriaceae, and some of them are dispersing worldwide. The acceleration of aminoglycoside resistance among gram-negative bacilli by producing plasmid-mediated 16S rRNA methylases, such as RmtC, RmtB, and RmtA, may indeed become an actual clinical hazard in the near future.  相似文献   
946.
947.

Background

Bordetella pertussis infection is a known trigger of atypical hemolytic uremic syndrome (HUS). For patients suspected of having atypical HUS, prompt plasma exchange/infusion (PE/PI) or eculizumab (ECZ) treatment is recommended.

Case presentation

We report a 1-month-old female infant who was admitted with a severe cough and a B. pertussis-positive sputum culture. She was born at 38?weeks gestation and did not have a family history of renal diseases. Hemophagocytic syndrome was suspected and she was transferred to our hospital 17?days after her initial admission. One day later, she developed acute kidney injury and was diagnosed with HUS triggered by B. pertussis infection. Her plasma complement levels were low and her kidney function continued to worsen over the next few days. However, prior to starting ECZ treatment, her kidney function improved spontaneously; she did not receive PE/PI or ECZ. She was discharged 46?days after her initial hospitalization, without complications. A genetic workup revealed no mutations in CFH, CFI, CFB, C3, MCP, THBD, or DGKE.

Conclusions

This case demonstrates that B. pertussis infection-related HUS may resolve spontaneously. The decision to treat during the acute phase is challenging because B. pertussis often affects infants suspected of having atypical HUS. However, ECZ may not be the first treatment option for patients with B. pertussis infection-related HUS unless they show an indicated genetic abnormality; if ECZ is used, early discontinuation should be considered.
  相似文献   
948.

Background and aims

Ultrasonography is the most frequently used modality in surveillance for HCC among patients with chronic hepatitis C. However, the optimal surveillance interval is still controversial and the usefulness of supplementary tumor marker determination has not been confirmed.

Methods

A total of 243 cases of naive HCC were detected among 1,431 patients with chronic hepatitis C under outpatient-based surveillance. The mode of HCC detection, including ultrasound surveillance interval, was retrospectively examined and the relation between the interval and detected tumor size was analyzed. Tumor volume doubling time was estimated from exponential increase in serum tumor marker levels when applicable.

Results

HCC was first detected by ultrasonography in 221 patients. Ultrasound surveillance interval, ranging between 2 and 8 months, was not correlated with the size of tumor at detection. Patients with cirrhosis were likely to be surveyed at shorter intervals. The size of tumor exceeded 30 mm only in three (1.4%) cases. They were all positive for a biomarker and the estimated tumor doubling time was short. In 14 cases, HCC was first detected by CT indicated by abnormal rise in tumor marker levels despite negative ultrasound findings. In the remaining eight cases, ultrasonography had been replaced by CT as surveillance modality because of excessive obesity or coarseness of liver parenchyma.

Conclusions

Ultrasound surveillance at 6-month intervals was appropriate in general for the detection of HCC at a size smaller than 30 mm. However, in patient with established cirrhosis, more frequent screening would be needed to detect tumors of the same size.  相似文献   
949.
Small bowel adenocarcinoma (SBA) in patients with Crohn's disease (CD) is quite rare, difficult to diagnose without surgery, and has a poor prognosis. Here, we report a 48-year-old man with SBA and a 21-year history of CD who was diagnosed by a combination of positron emission tomography/computed tomography (PET/CT) and double-balloon enteroscopy (DBE). Since the age of 27 years, the patient had been treated for ileal CD and was referred to our hospital with persistent melena. Multiple hepatic tumors were found by CT. PET/CT detected an accumulation spot in the small bowel. DBE revealed an ulcerative tumor in the ileum about 100 cm from the ileocecal valve. An endoscopic forceps biopsy specimen showed poorly differentiated adenocarcinoma. There were some longitudinal ulcer scars near the tumor, and the chronic inflammation in the small bowel appeared to be associated with the cancer development. Previous reports suggest the risk of SBA in patients with CD is higher than in the overall population. Since early diagnosis is extremely difficult in these cases, novel techniques, such as PET/CT and DBE, may be expected to help in making a preoperative diagnosis of the development of SBA in CD.  相似文献   
950.
Recent reports have shown that cardiomyopathy caused by hemochromatosis in severe aplastic anemia is reversible after reduced-intensity allogeneic stem-cell transplantation (RIST). We comprehensively evaluated cardiac and autonomic nerve function to determine whether cardiac dysfunction due to causes other than hemochromatosis is attenuated after RIST. In five patients with cardiac dysfunction before transplant, we analyzed the changes in cardiac and autonomic nerve function after transplant, using electrocardiography (ECG), echocardiography, radionuclide angiography (RNA), serum markers, and heart rate variability (HRV), before and up to 100 days after transplant. There was no significant improvement in cardiac function in any patient and no significant alteration in ECG, echocardiogram, RNA, or serum markers. However, on time-domain analysis of HRV, the SD of normal-to-normal RR intervals (SDNN) and the coefficient of variation of the RR interval (CVRR) decreased significantly 30 and 60 days after transplant (P = 0.04 and 0.01, respectively). Similarly, on frequency-domain analysis of HRV, low and high frequency power (LF and HF) significantly and temporarily decreased (P = 0.003 and 0.03, respectively). Notably, in one patient who had acute heart failure after transplantation, the values of SDNN, CVRR, r-MSSD, LF, and HF at 30 and 60 days after transplantation were the lowest of all the patients. In conclusion, this study suggests that (a) RIST is well-tolerated in patients with cardiac dysfunction, but we cannot expect improvement in cardiac dysfunction due to causes other than hemochromatosis; and (b) monitoring HRV may be useful in predicting cardiac events after RIST.  相似文献   
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