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61.
Ghrelin improves renal function in mice with ischemic acute renal failure   总被引:1,自引:0,他引:1  
Growth hormone and IGF-1 have been suggested to have tissue-protective effects. Ghrelin is a stomach-derived growth hormone secretagogue. The effects of ghrelin on ischemia/reperfusion-induced renal failure in mice were examined. Ischemic acute renal failure was induced by bilateral renal artery clamping for 45 min and reperfusion for 24 h. Ghrelin (100 microg/kg mouse) or vehicle was injected subcutaneously six times before surgery and three times after surgery every 8 h. Twenty-four hours after reperfusion, the right kidney was isolated and perfused. Acetylcholine (ACh)- and adrenomedullin-induced endothelium-dependent vasorelaxation of renal vessels significantly improved in ghrelin-pretreated mice (%Delta renal perfusion pressure by 10(-7) M ACh -63.5 +/- 3.7 versus -41.2 +/- 5.5%; P < 0.05). This change was associated with significant increases of nitric oxide release in the kidneys of ghrelin-treated mice (10(-7) M ACh 35.5 +/- 5.8 versus 16.9 +/- 3.5 fmol/g kidney per min; P < 0.05). Serum concentration of urea nitrogen (53 +/- 7 versus 87 +/- 15 mg/dl; P < 0.05) and renal injury score were significantly lower in the ghrelin group (2.5 +/- 0.8 versus 5.3 +/- 1.5; P < 0.01). Tubular apoptotic index was significantly lower in the ghrelin group (5 +/- 5 versus 28 +/- 4; P < 0.05). Furthermore, the survival rate after the 60-min ischemic period was higher in the ghrelin group (80 versus 20%; P < 0.05). Ghrelin treatment significantly increased the serum level of IGF-1. However, such renal protective effects of ghrelin on ischemia/reperfusion injury were not observed in insulin receptor substrate-2 knockout mice. These results suggest that ghrelin may protect the kidneys from ischemia/reperfusion injury and that this effect is related to an improvement of endothelial function through an IGF-1-mediated pathway.  相似文献   
62.
In order to obtain tractable aromatic poly(1.3.4-oxadiazoles), the polycondensation of pyridinedicarboxylic dihydrazides has been investigated according to the solution polycondensation procedure using fuming sulfuric acid or polyphosphoric acid as solvent and condensing agent. The resulting polymers were not wholly composed of the 1.3.4-oxadiazole structure, and their molecular weights were rather low (ηsp/c up to 0.18 dl/g). Some properties of the polymers, such as IR- and UV-spectra, solubility, and thermal stability, were compared with those of authentic poly(pyridine-1.3.4-oxadiazoles).  相似文献   
63.
We encountered a case of multiple metastatic brain tumors with simultaneous multiple cerebral hemorrhages. A 45-year-old male suffered from sudden left hemiplegia and was admitted to our hospital. CT scans on admission revealed multiple cerebral hemorrhages with surrounding brain edema in the right frontal lobe, left frontal lobe, right occipital lobe and right basal ganglia. On full-body examination, renal cell carcinoma of the left kidney and multiple metastatic tumors in the lung, liver and vertebral body were identified. We continued conservative therapy, but the patient's condition worsened and he died 36 days later. The autopsy findings indicated that all hemorrhages had occurred in the necrotic tissue associated with the metastatic brain tumors. Simultaneous multiple cerebral hemorrhages caused by metastatic brain tumors are very rare, and the differential diagnosis of cerebral hemorrhage due to metastatic brain tumor and hypertensive cerebral hemorrhage is difficult. The present case indicates that metastatic brain tumor should be taken into consideration in cases with simultaneous multiple intracerebral hemorrhages.  相似文献   
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We have reported that the apparent diffusion coefficient (ADC) was correlated with bone mineral density, but the relation between the restricted diffusion of the water molecules and the trabecular bone structure was unclear. The purpose of our study is to clarify this relationship using two component analyses with an original phantom. With an increase in the interspace area of the simulated trabecular bone, the ADC of the fast component was increased, and the fraction of the fast component was also increased. On the other hand, with an increase in the interspace area of the simulated trabecular bone, the ADC of the slow component was decreased, and the fraction of the slow component was increased. Moreover, the ADC and fraction of the dry vertebral bone agreed with those of the simulated trabecular bone. This result means that our phantoms can reproduce the actual trabecular bone structure, which induces the restricted diffusion. The diffusion of the water molecules was separated into fast and slow components because of the restricted diffusion of the trabecular bone structure. Our original phantom enables analyzing restricted diffusion, and this analytical method obtains more detailed information on trabecular bone structure.  相似文献   
67.
The incidence of allergic reactions in patients with chronic renal failure during plasma exchange using fresh frozen plasma is not well known. We retrospectively reviewed 62 patients who underwent plasma exchange between January 2013 and May 2018. The most common indication for plasma exchange was desensitization/preconditioning for kidney transplant (61.3%, 38/62). The incidence of allergic reactions was significantly higher in patients with chronic renal failure than patients without (57.1% vs. 25.0%, P = 0.029). Also, the incidence of allergic reactions tended to be higher in peritoneal dialysis patients (75%, 3/4) than in hemodialysis (58.8%, 10/17) and preemptive kidney transplant (58%, 11/19). These results suggested the relationship of chronic renal failure and the incidence of allergic reactions in patients undergoing therapeutic plasma exchange using fresh frozen plasma.  相似文献   
68.
Right pleural effusion was diagnosed in a 36-year-old woman with right upper quadrant pain and fever. Enhanced pelvic computed tomography performed because of irregular genital bleeding revealed the pelvic inflammatory disease. Upon further questioning, the patient confirmed that she had recently undergone therapy for Chlamydia trachomatis infection. Therefore she was given an injection of tetracycline because we suspected Fitz-Hugh-Curtis syndrome (FHCS), a pelvic inflammatory disease characterized by perihepatitis associated with chlamydial infection. A remarkable clinical response to antibiotics was noted. The right upper quadrant pain was due to perihepatitis, and the final diagnosis was FHCS. Right pleural effusion may be caused by inflammation of the diaphragm associated with perihepatitis. Once chlamydial infection reaches the subphrenic liver, conditions in the closed space between the liver and diaphragm due to inflammatory adhesion may be conductive to chlamydial proliferation. The possibility of FHCS should be considered in patients and carefully distinguished from other abdominal diseases.  相似文献   
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During a 53-month period (March 1994 to August 1998), 48 Corynebacterium striatum isolates recovered from clinical specimens were characterized. The organisms were identified by both phenotypic characteristics and 16S rRNA gene sequence analysis. Thirty-six (75%) were isolated from sputum/bronchial aspirates, 10 (21%) from wound exudates/pus, 1 (2%) from vaginal discharge, and 1 (2%) from an otorrheic specimen. All 48 patients had been hospitalized for treatment of an underlying disease and had received antibiotics previously. The C. striatum isolates were considered pathogenic based on their abundance within polymorphonuclear neutrophils and their dominant growth in culture. Sensitivities of isolates to 11 antibiotics were determined by broth microdilution. MIC90 values of the isolates were 1 microg/mL for vancomycin, 16 microg/mL for penicillin and ampicillin, 32 microg/mL for minocycline, and > or = 32 microg/mL for cephalosporins, imipenem, ofloxacin, and macrolides. Restriction fragment-length polymorphism analysis with pulsed-field gel electrophoresis was used to determine the clonal identity. The pulse-field gel electrophoresis profiles revealed 14 distinct patterns with 20 subtypes. The isolates for the nosocomial outbreaks of C. striatum included 3 types (A, D, and E) with 4 subtypes (A1, A2, D2, and E). All 4 genotypes had broad-spectrum resistance to antimicrobial agents. Furthermore, type E strain isolated from 3 patients in the same ward was sensitive only to vancomycin. We conclude that C. striatum should be considered an emerging multidrug-resistant nosocomial pathogen in patients hospitalized for a prolonged period and/or in immunocompromised patients with such underlying conditions as cerebrovascular disease, pulmonary disease, diabetes, or malignancy.  相似文献   
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