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11.
12.
Idiopathic pulmonary fibrosis (IPF) is a chronic, fibrosing interstitial lung disease that primarily affects older adults. Median survival after diagnosis is 2–3 years. The clinical course of IPF may include periods of acute deterioration in respiratory function, which are termed acute exacerbations of IPF (AEx-IPF) when a cause cannot be identified. AEx-IPF may represent a sudden acceleration of the underlying disease process of IPF, or a biologically distinct pathological process that is clinically undiagnosed. An AEx-IPF can occur at any time during the course of IPF and may be the presenting manifestation. The incidence of AEx-IPF is hard to establish due to variation in the methodology used to assess AEx-IPF in different studies, but AEx-IPF are believed to occur in between 5 and 10% of patients with IPF every year. Risk factors for AEx-IPF are unclear, but there is evidence that poorer lung function increases the risk of an AEx-IPF and reduces the chances of a patient surviving an AEx-IPF. The presence of comorbidities such as gastroesophageal reflux disease (GERD) and pulmonary hypertension may also increase the risk of an AEx-IPF. AEx-IPF are associated with high morbidity and mortality. Patients who experience an AEx-IPF show a worsened prognosis and AEx-IPF are believed to reflect disease progression in IPF. Current treatments for AEx-IPF have only limited data to support their effectiveness. The latest international treatment guidelines state that supportive care remains the mainstay of treatment for AEx-IPF, but also give a weak recommendation for the treatment of the majority of patients with AEx-IPF with corticosteroids. There is emerging evidence from clinical trials of investigational therapies that chronic treatment of IPF may reduce the incidence of AEx-IPF. Additional clinical trials investigating this are underway.  相似文献   
13.
Acute lung injury (ALI) is a severe pulmonary disease that causes a high number of fatalities worldwide. Studies have shown that FoxA1 expression is upregulated during ALI and may play an important role in ALI by promoting the apoptosis of alveolar type II epithelial cells. However, the mechanism of FoxA1 overexpression in ALI is unclear. In this study, an in vivo murine model of ALI and alveolar type II epithelial cells injury was induced using lipopolysaccharide (LPS). LPS upregulated FoxA1 in the lung tissue of the in vivo ALI model and in LPS-challenged type II epithelial cells. In contrast, miR-17 was significantly downregulated in these models. After miR-17 antagomir injection, the expression of FoxA1 was significantly increased in ALI mice. MiR-17 mimics could significantly inhibit FoxA1 mRNA and protein expression, whereas the miR-17 inhibitor could significantly increase FoxA1 mRNA and protein expression in LPS-induced type II epithelial cells. Thus, our results suggest that the downregulation of miR-17 expression could lead to FoxA1 overexpression in ALI.  相似文献   
14.

Objective

Traditionally, oestrogens were considered to be protective for the cardiovascular system for premenopausal women. Therefore, we conducted a retrospective case–control study to examine the association between endogenous oestrogens and acute myocardial infarction (AMI) risk among postmenopausal women.

Methods

A case–control study was performed among 30 primary AMI patients and 60 control subjects. Baseline characteristics data was collected and endogenous sex hormones levels were determined using chemoluminescence and radioimmunoassay methods. Conditional logistic regression models were developed with adjustment for confounders.

Results

Compared with controls, the circulating oestrone, oestradiol, androstenedione and testosterone levels were significantly higher in AMI patients (P < 0.05) while the sex hormone binding globulin (SHBG) level was lower (P < 0.05). Spearman correlation coefficients showed oestradiol was positively correlated with body mass index (BMI) and waist-to-hip ratio (WHR) in cases, but not in controls. In univariable conditional logistic regression models, oestrone, oestradiol, testosterone, WHR, BMI, diabetes and hypertension were all found to be positively associated with AMI (P < 0.05). After adjusting for these factors, oestradiol (odds ratio (OR) = 4.75; 95 % confidence interval (CI) = 1.07–21.10; P = 0.04) and WHR (OR = 6.46; 95 % CI = 1.09–38.39; P = 0.04) continued to demonstrate strong positive associations with AMI.

Conclusions

A higher level of oestradiol was potentially associated with primary AMI risk among postmenopausal women.  相似文献   
15.
Hyptis pectinata L. Poit (Lamiaceae) is known popularly in Brazil as “sambacaita” or “canudinho” and is used in the treatment of inflammations, bacterial infections and ache. The antinociceptive activity of the volatile oils of six genotypes, at doses of 100, 200 and 400 mg/kg body wt., were investigated using abdominal writhe models induced by acetic acid and hot plate tests. The volatile oils of all the genotypes are composed mainly of sesquiterpenoids. All the genotypes showed antinociceptive effects in both models used; the SAM002 genotype showed the major inhibitory effect at dose of 100 mg/kg body wt. These results suggest that the volatile oil of H. pectinata has peripheral (writhe reduction) and central (time delay of thermal reaction) effects. These observations indicate that H. pectinata may be useful as an analgesic drug.  相似文献   
16.
Netherlands Heart Journal - The current standard of care for acute atrial fibrillation (AF) focuses primarily on immediate restoration of sinus rhythm by cardioversion, although AF often terminates...  相似文献   
17.
Tissue nonspecific alkaline phosphatase (TNAP) has a well established role in bone homeostasis and in hepatic/biliary conditions. In addition, TNAP is expressed in the inflamed intestine and is relevant to T and B lymphocyte function. TNAP KO mice are only viable for a few days, but TNAP+/? haplodeficient mice are viable. Acute pancreatitis was induced by repeated caerulein injection in WT and TNAP+/? mice. TNAP+/? mice presented an increased expression of Cxcl2, Ccl2, Selplg (P-selectin ligand), Il6 and Il1b in the pancreas. Freshly isolated acinar cells showed a dramatic upregulation of Cxcl1, Cxcl2, Ccl2, Il6, Selpg or Bax in both pancreatitis groups. TNAP+/? cells displayed a 2-fold higher expression of Cxcl2, and a smaller increase in Il6. These findings could be partly replicated by in vitro treatment of primary acinar cells with caerulein. Furthermore, the proinflammatory effect on acinar cells could be partially reproduced in wild type cells treated with the TNAP inhibitor levamisole. TNAP mRNA levels were also markedly upregulated by pancreatitis in acinar cells. Neutrophil infiltration (MRP8+ cells) and activation (IL-6 and TNF production in LPS treated primary neutrophils) were increased in TNAP+/? vs WT mice. Neutrophil depletion greatly attenuated inflammation, indicating that this cell type is mainly responsible for the higher inflammatory status of TNAP+/? mice. In conclusion, our results show that altered TNAP expression results in heightened pancreatic inflammation, which may be explained by an augmented response of neutrophils and by a higher sensitivity of acinar cells to caerulein injury.  相似文献   
18.
As part of our ongoing efforts to develop reversible inhibitors of LSD1, we identified a series of 4-(pyrrolidin-3-yl)benzonitrile derivatives that act as successful scaffold-hops of the literature inhibitor GSK-690. The most active compound, 21g, demonstrated a Kd value of 22 nM and a biochemical IC50 of 57 nM. In addition, this compound displayed improved selectivity over the hERG ion channel compared to GSK-690, and no activity against the related enzymes MAO-A and B. In human THP-1 acute myeloid leukaemia cells, 21g was found to increase the expression of the surrogate cellular biomarker CD86. This work further demonstrates the versatility of scaffold-hopping as a method to develop structurally diverse, potent inhibitors of LSD1.  相似文献   
19.
CD8+ T cell responses are important for recognizing and resolving viral infections. To better understand the selection and hierarchy of virus-specific T cell responses, we compared the T cell receptor (TCR) clonotype in parent and hybrid strains of respiratory syncytial virus-infected mice. K(d)M2(82-90) (SYIGSINNI) in BALB/c and D(b)M(187-195) (NAITNAKII) in C57Bl/6 are both dominant epitopes in parent strains but assume a distinct hierarchy, with K(d)M2(82-90) dominant to D(b)M(187-195) in hybrid CB6F1/J mice. The dominant K(d)M2(82-90) response is relatively public and is restricted primarily to the highly prevalent Vβ13.2 in BALB/c and hybrid mice, whereas D(b)M(187-195) responses in C57BL/6 mice are relatively private and involve multiple Vβ subtypes, some of which are lost in hybrids. A significant frequency of TCR CDR3 sequences in the D(b)M(187-195) response have a distinct "(D/E)WG" motif formed by a limited number of recombination strategies. Modeling of the dominant epitope suggested a flat, featureless structure, but D(b)M(187-195) showed a distinctive structure formed by Lys(7). The data suggest that common recombination events in prevalent Vβ genes may provide a numerical advantage in the T cell response and that distinct epitope structures may impose more limited options for successful TCR selection. Defining how epitope structure is interpreted to inform T cell function will improve the design of future gene-based vaccines.  相似文献   
20.
目的:探讨经皮肾微造瘘术后Ⅱ期经皮输尿管镜治疗输尿管上段结石致孤立肾急性肾功能衰竭的安全性与有效性。方法:从2004年7月~2009年5月,利用经皮肾微造瘘建立经皮肾通道,引流1周后肾功能明显好转,再行经皮肾输尿管镜碎石治疗孤立肾输尿管上段结石。结果:16例患者中,所有患者均为单通道取石,结石清除率例(81.2%),未出现高热、出血等并发症。术后1月复查13例无结石残留。结论:微创经皮输尿管镜分期治疗输尿管上段结石致孤立肾急性肾功能衰竭是安全、有效的,同传统经皮肾镜相比,具有对病人创伤小,易恢复等优点。  相似文献   
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