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We investigated the morphologic changes in the sarcoplasmic reticulum (SR) in acute myocardial ischemia, induced by occlusion of the coronary artery in the canine heart, by freeze-fracture of SR in situ and in vitro, and they were compared to the alterations in Ca++-stimulated ATPase activity and protein composition of the isolated SR. Both SR in situ and the isolated SR exhibited typical intramembranous particles with diameters of 70 to 90 A in freeze-fracture replicas. The intramembranous particle density of the P face in SR in situ was 3,319 +/- 75 (mean +/- SE) per micrometer2 and that in the isolated SR was 2,667 +/- 60; particles were more numerous on the concave (P) face than on the convex (E) face. In ischemia for 30 to 60 min a significant decrease in the number of particles was found in SR in situ, and the corresponding change was noted in the isolated SR. Simultaneous decreases in Ca++-stimulated ATPase activity and the major ATPase protein of the SR were recognized. The close correlation of the changing pattern between the reduction in Ca++-ATPase and that in intramembranous particle density during ischemia supports the suggestion that a large part of the intramembranous particles represent ATPase protein itself. Decrease in the SR membrane particles strongly suggests the degradation of ATPase protein in the process of ischemic myocardial injury.  相似文献   
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We report a case of interstitial cystitis (IC) associated with primary Sjögren's syndrome (SS) successfully controlled with combination therapy of tacrolimus and a corticosteroid. In 2011, a 69-year-old female, who had been diagnosed with primary SS 23 years ago, developed IC and was successfully treated with tacrolimus and prednisolone combination therapy. The mechanism of IC, including the involved autoimmunity, has not been elucidated. Clinical observation studies suggest a potential association between SS and IC. However, IC is currently thought to be underdiagnosed in patients with SS as well as in the general population. Based on our case and others reported previously, IC associated with SS responds well to immunosuppressive therapy. In particular, a combination of a calcineurin inhibitor (tacrolimus or cyclosporine) with a corticosteroid seems to be highly effective. The possibility of IC in patients with SS complaining of lower urinary tract symptoms without features of infection or other identifiable causes should be given attention.  相似文献   
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BACKGROUND Although several techniques for endoscopic ultrasound-guided biliary drainage(EUS-BD)are available at present,an optimal treatment algorithm of EUS-BD has not yet been established.AIM To evaluate the clinical utility of treatment method conversion during single endoscopic sessions for difficult cases in initially planned EUS-BD.METHODS This was a single-center retrospective analysis using a prospectively accumulated database.Patients with biliary obstruction undergoing EUS-BD between May 2008 and April 2016 were included.The primary outcome was to evaluate the improvement in EUS-BD success rates by converting the treatment methods during a single endoscopic session.Secondary outcomes were clarification of the factors leading to the conversion from the initial EUS-BD and the assessment of efficacy and safety of the conversion as judged by technical success,clinical success,and adverse events(AEs).RESULTS A total of 208 patients underwent EUS-BD during the study period.For 18.8%(39/208)of the patients,the treatment methods were converted to another EUSBD technique from the initial plan.Biliary obstruction was caused by pancreatobiliary malignancies,other malignant lesions,biliary stones,and other benign lesions in 22,11,4,and 2 patients,respectively.The reasons for the difficulty with the initial EUS-BD were classified into the following 3 procedures:Target puncture(n=13),guidewire manipulation(n=18),and puncture tract dilation(n=8).Technical success was achieved in 97.4%(38/39)of the cases and clinical success was achieved in 89.5%of patients(34/38).AEs occurred in 10.3%of patients,including bile leakage(n=2),bleeding(n=1),and cholecystitis(n=1).The puncture target and drainage technique were altered in subsequent EUSBD procedures in 25 and 14 patients,respectively.The final technical success rate with 95%CI for all 208 cases was 97.1%(95%CI:93.8%-98.9%),while that of the initially planned EUS-BD was 78.8%(95%CI:72.6%-84.2%).CONCLUSION Among multi-step procedures in EUS-BD,guidewire manipulation appeared to be the most technically challenging.When initially planned EUS-BD is technically difficult,treatment method conversion in a single endoscopic session may result in successful EUS-BD without leading to severe AEs.  相似文献   
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The reliability of a loop-mediated isothermal amplification (LAMP) method for the detection of human herpesvirus 8 (HHV-8) DNA was evaluated. Although LAMP products were produced with the DNA sample extracted from BCP-1 cells, LAMP products were not produced with the DNAs from seven other human herpesviruses. The detection limit of the HHV-8 LAMP method was 100 copies of target sequence/tube. To determine whether the HHV-8 LAMP method could be used to quantify viral DNA, threshold times, which are defined as the time (in s) it takes to reach the threshold turbidity level (0.1), were measured for the amplification of serial dilutions of a DNA plasmid containing the target sequence. The standard curve possessed a correlation coefficient of 0.9428 with a slope of -84.079 and y-intercept value of 1936.2. Additionally, an attempt was made to detect viral DNA in 17 specimens collected from Kaposi's sarcomas and two cell lines obtained from primary effusion lymphomas. HHV-8 DNA was detected in 14 of the 17 Kaposi's sarcoma tissue samples and both of the primary effusion lymphoma cell lines. Viral DNA was not detected in HHV-8 LAMP-negative samples using the real-time PCR method.  相似文献   
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CONTEXT: Mouse knockout models have clearly demonstrated the critical importance of IGF-I and IGF receptor type 1 (IGF-IR) for embryonic growth as well as postnatal growth. OBJECTIVE: We hypothesized that mutations of IGF-IR gene might predispose to short stature in children born with intrauterine growth retardation (IUGR). PATIENTS: Twenty-four children with unexplained IUGR (birth weight < -1.5 SD) and short stature (<-2.0 SD) were screened for abnormalities of the IGF-IR gene. METHODS: Direct DNA sequencing was used to identify IGF-IR gene mutations. Unprocessed IGF-IR proreceptor in fibroblasts was detected by immunoblot analysis. Functions of mutated IGF-IR in fibroblasts were evaluated by IGF-I binding, and IGF-I-stimulated DNA synthesis and beta-subunit autophosphorylation. RESULTS: We found the following results: 1) a heterozygous mutation (R709Q) changing the cleavage site from Arg-Lys-Arg-Arg to Arg-Lys-Gln-Arg was identified in a 6-yr-old Japanese girl (case 1) and her mother who also had IUGR with short stature (case 2); 2) fibroblasts from case 2 contained more IGF-IR proreceptor protein (189 +/- 26% of normal) and less mature beta-subunit protein (63 +/- 12%); 3) [125I]IGF-I binding to fibroblasts from case 2 was reduced, compared with normal control (0.61 +/- 0.16 x 10(6) vs. 1.14 +/- 0.12 x 10(6) sites per cell; P < 0.05); and 4) both IGF-I-stimulated [3H]thymidine incorporation and IGF-IR beta-subunit autophosphorylation were low in fibroblasts from case 2, compared with those of control (P < 0.05). CONCLUSIONS: These findings strongly suggest that this mutation leads to failure of processing of the IGF-IR proreceptor to mature IGF-IR and causes short stature and IUGR.  相似文献   
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An 81-year-old man was admitted to the hospital with a severe sore throat and a low grade fever. A chest radiograph showed bilateral diffuse reticulonodular shadows. By fluorescent stain for mycobacteria, his sputum smear showed acid-fast bacteria. The initial polymerase chain reaction (PCR) of his sputum revealed Mycobacterium intracellulare (M. intracellulare), but not Mycobacterium tuberculosis (M. tuberculosis). However, a repeat PCR was performed because M. tuberculosis could not be ruled out due to his clinical symptoms and chest imaging. The second PCR detected both M. intracellulare and M. tuberculosis. From the standpoint of infection control, this case illustrates the possibility that M. tuberculosis could be a threat if a second PCR is not done. While PCR is a useful exam for diagnosing M. tuberculosis, it can produce false negative results. Therefore, for diagnosing tuberculosis, particularly in a case such as the present case, a second PCR, which is not normally necessary, should be done.  相似文献   
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