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21.
Li Y  Azuma A  Takahashi S  Usuki J  Matsuda K  Aoyama A  Kudoh S 《Chest》2002,122(6):2137-2145
BACKGROUND AND OBJECTIVE: Although the pathogenesis of interstitial pneumonia and pulmonary fibrosis are not well understood, it has been reported that inflammatory cells, especially neutrophils, and the injurious substances produced by them play important roles in the progression of interstitial pneumonia and subsequent fibrosis. Erythromycin and other 14-membered ring macrolides (14-MRMLs) have been reported to improve the survival of patients with diffuse panbronchiolitis by antineutrophil and several other anti-inflammatory mechanisms. The present study was undertaken to investigate the effects of 14-MRMLs on an experimental model of bleomycin-induced acute lung injury and subsequent fibrosis in mice. METHODS: Bleomycin was administered IV to ICR mice. At 28 days after bleomycin injection, fibrotic foci were histologically observed in left lung tissues, and hydroxyproline content in right lung tissues was chemically analyzed. The inhibitory effects of 14-MRMLs were assessed by overall comparison between control (normal saline solution [NS] alone), untreated (bleomycin alone), and treated (bleomycin plus 14-MRMLs) groups. For evaluation of early-phase inflammation, cell populations in BAL fluid and induction of messenger RNA (mRNA) of adhesion molecules (E-selectin, P-selectin, intercellular adhesion molecule 1 [ICAM-1], and vascular cell adhesion molecule 1 [VCAM-1]) in lung tissues were examined at 0 to 13 days after bleomycin treatment. These parameters were also compared with those for the control (NS alone), 14-MRML untreated (bleomycin alone), and 14-MRML pretreated (bleomycin plus 14-MRML pretreated) groups. RESULTS: Bleomycin-induced pulmonary fibrosis was inhibited by erythromycin and other 14-MRMLs on day 28 after bleomycin injection in ICR mice, especially those pretreated with 14-MRMLs. Hydroxyproline content in lung tissues was also decreased in the 14-MRML-pretreated groups. The number of neutrophils in BAL fluid significantly increased, with two peaks at 1 day and 9 days (from 6 to 11 days) after bleomycin administration. 14-MRMLs significantly inhibited both peaks of neutrophil infiltration into the airspace. Changes in mRNA expression of adhesion molecules (E-selectin, P-selectin, ICAM-1, VCAM-1) were associated with leukocyte migration into the airspace. 14-MRMLs clearly inhibited the induction of VCAM-1 mRNA, and tended to attenuate that of ICAM-1 mRNA, but inhibited the induction of neither E-selectin mRNA nor P-selectin mRNA. CONCLUSION: These findings indicate that attenuation of inflammatory cell migration into the airspace by 14-MRMLs, especially of neutrophils and macrophages, resulted in inhibition of lung injury and subsequent fibrosis. 14-MRMLs clearly attenuated the expression of VCAM-1 mRNA during the early phase of bleomycin-induced lung injury, and this might be one mechanism of inhibition of neutrophil and macrophage migration into the airspace by 14-MRMLs. This may be one mechanism of the anti-inflammatory and antifibrotic effects of 14-MRMLs. These findings suggest that prophylactic administration of 14-MRMLs may be clinically efficacious in preventing acute exacerbation of interstitial pneumonia and acute lung injury.  相似文献   
22.
Primary pericardial sarcomas are very rare. A 62-year-old Japanese man presented with cardiac tamponade. Echocardiography, computed tomography and magnetic resonance imaging revealed massive pericardial effusion and a large tumor in the pericardial cavity, attached to the pericardium of the left ventricular posterolateral free wall. Surgical excision of the tumor was performed and histopathological and immunohistochemical examinations identified high-grade myofibroblastic sarcoma. Because of local recurrence soon after surgery, the patient received adjuvant chemotherapy, including doxorubicin and ifosfamide, and subsequent radiotherapy. As of 6 months after completing radiotherapy, the patient was alive and no disease progression or distant metastases were evident. This may be the first report of primary high-grade myofibroblastic sarcoma arising from the pericardium.  相似文献   
23.
In recent years, augmented renal clearance (ARC), in which renal function is excessively enhanced, has been reported, and its influence on β-lactam antibiotics has been investigated. In this study, we aimed to determine the optimum population pharmacokinetic model of meropenem in patients with sepsis with ARC, and evaluated dosing regimens based on renal function. Seventeen subjects (6 with ARC and 11 without) were enrolled in this study. Predicted meropenem concentrations were evaluated for bias and precision using the Bland–Altman method. To examine the dosing regimen, Monte Carlo simulation was performed to calculate the cumulative fraction of response (CFR). In patients with ARC, the bias (average of the predicted value and measured value residuals) of models constructed by Crandon et al. (2011), Roberts et al. (2009), and Jaruratanasirikul et al. (2015) were 5.96 μg/mL, 10.91 μg/mL, and 4.41 μg/mL, respectively. Following 2 g meropenem every 8 h (180 min infusion), CFR ≥ 90%, a criterion of success for empirical therapy, was achieved, even with creatinine clearance of 130–250 mL/min. For patients with sepsis and ARC, the model of Jaruratanasirikul et al. showed the highest degree of accuracy and precision and confirmed the efficacy of the meropenem dosing regimen in this patient population.  相似文献   
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A 55-year-old woman with a history of right hepatic lobectomy via a Benz incision presented for evaluation of a new abdominal bulge in the right upper quadrant. We diagnosed an incisional hernia, but because we could neither reduce the hernia contents nor locate the orifice, we performed a laparoscopic evaluation. Laparoscopy revealed subcostal herniation of the greater omentum via a 2-cm defect on the caudal side of the right ribs, which we repaired using a Ventralex ST Hernia Patch. Laparoscopic placement of this mesh with straps allowed for reliable deployment, fixation, and confirmation of defect closure, including the cranial aspect—often a major challenge in subcostal hernia repair.  相似文献   
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Effects of vitamin K(2) (menatetrenone) and alendronate on bone mineral content and bone mechanical property in rats fed a low-magnesium diet. Recent clinical studies have shown that the occurrence of new fractures does not always depend on bone mineral density. Therefore bone quality has become an important issue in osteoporosis research. No animal model for evaluating bone quality has been established. In this study, we found that the treatment of rats with a low-magnesium (Mg) diet reduced their bone strength without decreasing bone mineral content (BMC), so the low Mg diet model is considered to be a good model for examining bone quality. Using this model, we investigated the effects of vitamin K(2) (V.K(2)) and alendronate (ALN). V.K(2) increased maximum load and elastic modulus without influencing BMC. ALN increased maximum load with increasing BMC. By using Fourier transform infrared microscopic analysis, the low-Mg diet treatment increased the mineral/matrix ratio of bones, and V.K(2) suppressed the increase in this ratio. These findings suggest that the mineral/matrix ratio may be a factor involved in bone quality, and that V.K(2) may improve bone quality.  相似文献   
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Matrix metalloproteinases (MMPs) that are secreted by activated T cells play a significant role in degradation of the extracellular matrix around the blood vessels and facilitate autoimmune neuroinflammation; however, it remains unclear how MMPs act in lesion formation and whether MMP‐targeted therapies are effective in disease suppression. In the present study, we attempted to treat experimental autoimmune encephalomyelitis (EAE) by administration of small interfering RNAs (siRNAs) for MMP‐2, MMP‐9, and minocycline, all of which have MMP‐inhibiting functions. Minocycline, but not siRNAs, significantly suppressed disease development. In situ zymography revealed that gelatinase activities were almost completely suppressed in the spinal cords of minocycline‐treated animals, while significant gelatinase activities were measured in the EAE lesions of control animals. However, MMP‐2 and MMP‐9 mRNAs and proteins in the spinal cords of treated rats were unexpectedly upregulated. At the same time, mRNA for tissue inhibitors of MMPs (TIMP)‐1 and ‐2 were also upregulated. The EnzChek Gelatinase/Collagenase assay using tissue containing native MMPs and TIMPs demonstrated that gelatinase activity levels in the spinal cords of treated rats were suppressed to the same level as those in normal spinal cord tissues. Finally, double immunofluorescent staining demonstrated that MMP‐9 immunoreactivities of treated rats were almost the same as those of control rats and that MMP‐9 and TIMP‐1 immunoreactivities were colocalized in the spinal cord. These findings suggest that minocycline administration does not suppress MMPs at mRNA and protein levels but that it suppresses gelatinase activities by upregulating TIMPs. Thus, MMP‐targeted therapies should be designed after the mechanisms of candidate drugs have been considered.  相似文献   
30.
BackgroundFew studies have investigated right atrial (RA) remodeling in heart failure (HF) with preserved ejection fraction (HFpEF). This study sought to characterize the RA remodeling in HFpEF and to determine its prognostic significance.Methods and ResultsPatients with HFpEF were classified based on the presence of RA enlargement (RA volume index >39 mL/m2 in men and >33 mL/m2 in women). Compared with patients with normal RA size (n = 234), patients with RA dilation (n = 67) showed a higher prevalence of atrial fibrillation (AF), worse right ventricular systolic function, more severe pulmonary hypertension, and a greater prevalence of mild tricuspid regurgitation, as well as impaired RA reservoir function, with increased hepatobiliary enzyme levels. AF was strongly associated with the presence of RA dilation (odds ratio [OR] 10.2, 95% confidence interval [CI] 4.00–26.1 in current AF vs no AF and odds ratio 3.38, 95% CI 1.26–9.07, earlier AF vs no AF). Patients with RA dilation had more than a two-fold increased risk of composite outcomes of all-cause mortality or HF hospitalization (adjusted hazard ratio 2.01, 95% CI 1.09–3.70, P = .02). The presence of RA dilation also displayed an additive prognostic value over left atrial dilation alone.ConclusionsThese data demonstrate that HFpEF with RA remodeling is associated with distinct echocardiographic features characterizing advanced right heart dysfunction with an increased risk of adverse outcomes.  相似文献   
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