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131.
BackgroundThe relationship between asthma and ankylosing spondylitis (AS) is controversial. We examined the risk of asthma among AS patients in a nationwide population.MethodsWe conducted a retrospective cohort study using data from the National Health Insurance (NHI) system of Taiwan. The cohort included 5,974 patients newly diagnosed with AS from 2000 to 2010. The date of diagnosis was defined as the index date. A 4-fold of general population without AS was randomly selected frequency matched by age, gender and the index year. The occurrence and hazard ratio (HR) of asthma were estimated by the end of 2011.ResultsThe overall incidence of asthma was 1.74 folds greater in the AS cohort than in the non-AS cohort (8.26 versus 4.74 per 1000 person-years) with a multivariable Cox method measured adjusted HR of 1.54 (95% confidence interval (CI), 1.34–1.76). The adjusted HR of asthma associated with AS was higher in women (1.59; 95% CI, 1.33–1.90), those aged 50–64 years (1.66; 95% CI, 1.31–2.09), or those without comorbidities (1.82; 95% CI, 1.54–2.13).ConclusionPatients with AS are at a higher risk of developing asthma than the general population, regardless of gender and age. The pathophysiology needs further investigation.  相似文献   
132.
133.
The effects of different particle sizes (100–150, 74–100, and <74 μm) of powder of the dried and ground stipe from the monkey head mushroom, Hericium erinaceum, on the immune response and disease resistance of white shrimp, Litopenaeus vannamei, against the pathogen, Vibrio alginolyticus, were examined. Mushroom powder with a particle size of <74 μm had a significantly higher effect on the disease resistance of shrimp compared to particle sizes of >74 μm. Mortality of shrimp after being injected with V. alginolyticus was particle size-dependent, increasing from 66.7% ± 3.3%–93.3% ± 3.3% with diets containing stipe particle sizes of <74 and 100–150 μm, respectively. The mortality of shrimp fed the diet containing <74-μm stipe powder for 28 days was significant lower than that of shrimp fed with the control diet and the diet containing 74–100-μm stipe powder after being challenged by V. alginolyticus. The optimal concentration of the <74-μm mushroom powder for enhancing the immune response and disease resistance of shrimp was 0.2 μg (g shrimp)?1 day?1. No significant change in the total hemocyte count, differential hemocyte count, glutathione reductase, or phagocytic activity was found in shrimp fed the control diet and mushroom powder-containing diet at a level of up to 0.2 μg (g shrimp)?1 day?1. Shrimp fed 0.2 μg (g shrimp)?1 day?1 of a mushroom-containing diet had a significantly higher disease resistance to V. alginolyticus via an increase in phenoloxidase activity, respiratory bursts, superoxide dismutase activity, and glutathione peroxidase activity. Therefore, a diet containing the stipe powder of monkey head mushroom with a particle size <74 μm at a level of 0.2 μg (g shrimp)?1 day?1 was found to enhance the immunity and disease resistance of shrimp.  相似文献   
134.
Liver is the largest organ in the human body, and it regulates many physiological processes. Many studies on liver development in different model organisms have demonstrated that the mechanism of hepatogenesis is conserved in vertebrates. The identification of the genes and regulatory pathways involved in liver formation provides a basis for the diagnosis of liver diseases and therapeutic interventions. Hepatocellular carcinoma is the third leading cause of mortality worldwide. In the last decade, genetic alterations, which include the gain and loss of DNA, as well as mutations and epigenomic changes, have been identified as important factors in liver cancer. Many genetic pathways are dysregulated during carcinogenesis. Here, we review the gene regulatory networks that underlie liver organogenesis and the dysregulation of these pathways in liver cancer. The genes and pathways involved in hepatogenesis and liver cancer are largely conserved between zebrafish and humans, making this an ideal model organism for the study of this disease. A better understanding of liver development may aid in the development of new diagnostic and therapeutic approaches to liver cancer.  相似文献   
135.
Modern spiders spin high-performance silk fibers with a broad range of biological functions, including locomotion, prey capture and protection of developing offspring 1,2. Spiders accomplish these tasks by spinning several distinct fiber types that have diverse mechanical properties. Such specialization of fiber types has occurred through the evolution of different silk-producing glands, which function as small biofactories. These biofactories manufacture and store large quantities of silk proteins for fiber production. Through a complex series of biochemical events, these silk proteins are converted from a liquid into a solid material upon extrusion.Mechanical studies have demonstrated that spider silks are stronger than high-tensile steel 3. Analyses to understand the relationship between the structure and function of spider silk threads have revealed that spider silk consists largely of proteins, or fibroins, that have block repeats within their protein sequences 4. Common molecular signatures that contribute to the incredible tensile strength and extensibility of spider silks are being unraveled through the analyses of translated silk cDNAs. Given the extraordinary material properties of spider silks, research labs across the globe are racing to understand and mimic the spinning process to produce synthetic silk fibers for commercial, military and industrial applications. One of the main challenges to spinning artificial spider silk in the research lab involves a complete understanding of the biochemical processes that occur during extrusion of the fibers from the silk-producing glands.Here we present a method for the isolation of the seven different silk-producing glands from the cobweaving black widow spider, which includes the major and minor ampullate glands [manufactures dragline and scaffolding silk] 5,6, tubuliform [synthesizes egg case silk] 7,8, flagelliform [unknown function in cob-weavers], aggregate [makes glue silk], aciniform [synthesizes prey wrapping and egg case threads] 9 and pyriform [produces attachment disc silk] 10. This approach is based upon anesthetizing the spider with carbon dioxide gas, subsequent separation of the cephalothorax from the abdomen, and microdissection of the abdomen to obtain the silk-producing glands. Following the separation of the different silk-producing glands, these tissues can be used to retrieve different macromolecules for distinct biochemical analyses, including quantitative real-time PCR, northern- and western blotting, mass spectrometry (MS or MS/MS) analyses to identify new silk protein sequences, search for proteins that participate in the silk assembly pathway, or use the intact tissue for cell culture or histological experiments.  相似文献   
136.

Objectives

We examined the charges, their variability, and respective payer group for diagnosis and treatment of the ten most common outpatient conditions presenting to the Emergency department (ED).

Methods

We conducted a cross-sectional study of the 2006–2008 Medical Expenditure Panel Survey. Analysis was limited to outpatient visits with non-elderly, adult (years 18–64) patients with a single discharge diagnosis.

Results

We studied 8,303 ED encounters, representing 76.6 million visits. Median charges ranged from $740 (95% CI $651–$817) for an upper respiratory infection to $3437 (95% CI $2917–$3877) for a kidney stone. The median charge for all ten outpatient conditions in the ED was $1233 (95% CI $1199– $1268), with a high degree of charge variability. All diagnoses had an interquartile range (IQR) greater than $800 with 60% of IQRs greater than $1550.

Conclusion

Emergency department charges for common conditions are expensive with high charge variability. Greater acute care charge transparency will at least allow patients and providers to be aware of the emergency department charges patients may face in the current health care system.  相似文献   
137.

Background

Evidence about the efficacy and safety of statin treatment in high-risk patients with hypercholesterolemia is available for some populations, but not for ethnic Chinese. To test the hypothesis that treatment with pitavastatin (2 mg/day) is not inferior to treatment with atorvastatin (10 mg/day) for reducing low-density lipoprotein cholesterol (LDL-C), a 12-week multicenter collaborative randomized parallel-group comparative study of high-risk ethnic Chinese patients with hypercholesterolemia was conducted in Taiwan. In addition, the effects on other lipid parameters, inflammatory markers, insulin-resistance-associated biomarkers and safety were evaluated.

Methods and Results

Between July 2011 and April 2012, 251 patients were screened, 225 (mean age: 58.7 ± 8.6; women 38.2% [86/225]) were randomized and treated with pitavastatin (n = 112) or atorvastatin (n = 113) for 12 weeks. Baseline characteristics in both groups were similar, but after 12 weeks of treatment, LDL-C levels were significantly lower: pitavastatin group = −35.0 ± 14.1% and atorvastatin group = −38.4 ± 12.8% (both: p < 0.001). For the subgroup with diabetes mellitus (DM) (n = 125), LDL-C levels (−37.1 ± 12.9% vs. −38.0 ± 13.1%, p = 0.62) were similarly lowered after either pitavastatin (n = 63) or atorvastatin (n = 62) treatment. Triglycerides, non-high density lipoprotein cholesterol, and apoprotein B were similarly and significantly lower in both treatment groups. In non-lipid profiles, HOMA-IR and insulin levels were higher to a similar degree in both statin groups. Hemoglobin A1C was significantly (p = 0.001) higher in the atorvastatin group but not in the pitavastatin group. Both statins were well tolerated, and both groups had a similar low incidence of treatment-emergent adverse events.

Conclusion

Both pitavastatin (2 mg/day) and atorvastatin (10 mg/day) were well tolerated, lowered LDL-C, and improved the lipid profile to a comparable degree in high-risk Taiwanese patients with hypercholesterolemia.

Trial Registration

ClinicalTrials.gov NCT01386853 http://clinicaltrials.gov/ct2/show/NCT01386853?term=NCT01386853&rank=1  相似文献   
138.
In adult canines following major lung resection, the remaining lobes expand asymmetrically, associated with alveolar tissue regrowth, remodeling, and progressive functional compensation over many months. To permit noninvasive longitudinal assessment of regional growth and function, we performed serial high-resolution computed tomography (HRCT) on six male dogs (~9 mo old, 25.0 ± 4.5 kg, ±SD) at 15 and 30 cmH(2)O transpulmonary pressure (Ptp) before resection (PRE) and 3 and 15 mo postresection (POST3 and POST15, respectively) of 65-70% of lung units. At POST3, lobar air volume increased 83-148% and tissue (including microvascular blood) volume 120-234% above PRE values without further changes at POST15. Lobar-specific compliance (Cs) increased 52-137% from PRE to POST3 and 28-79% from POST3 to POST15. Inflation-related parenchyma strain and shear were estimated by detailed registration of corresponding anatomical features at each Ptp. Within each lobe, regional displacement was most pronounced at the caudal region, whereas strain was pronounced in the periphery. Regional three-dimensional strain magnitudes increased heterogeneously from PRE to POST3, with further medial-lateral increases from POST3 to POST15. Lobar principal strains (PSs) were unchanged or modestly elevated postresection; changes in lobar maximum PS correlated inversely with changes in lobar air and tissue volumes. Lobar shear distortion increased in coronal and transverse planes at POST3 without further changes thereafter. These results establish a novel use of functional HRCT to map heterogeneous regional deformation during compensatory lung growth and illustrate a stimulus-response feedback loop whereby postresection mechanical stress initiates differential lobar regrowth and sustained remodeling, which in turn, relieves parenchyma stress and strain, resulting in progressive increases in lobar Cs and a delayed increase in whole lung Cs.  相似文献   
139.
In adult dogs following right pneumonectomy (PNX) and receiving all-trans-retinoic acid (RA) supplementation for 4 mo, we found modestly enhanced alveolar-capillary growth in the remaining lung without enhanced resting lung function (J Appl Physiol 96: 1080-1089 and 96: 1090-1096, 2004). Since alveolar remodeling progresses beyond this period and the lipid-soluble RA continues to be released from tissue stores, we hypothesized that RA supplementation may exert additional long-term effects. To examine this issue, adult male litter-matched foxhounds underwent right PNX followed by RA supplementation (2 mg/kg po 4 days/wk, n = 6) or placebo (n = 4) for 4 mo. Cardiopulmonary function was measured at rest and during exercise at 4 and 20 mo post-PNX. The remaining lung was fixed under a constant airway pressure for morphometric analysis. Comparing RA treatment to placebo controls, there were no differences in aerobic capacity, cardiopulmonary function, or lung volume at rest or exercise. Alveolar-capillary basal lamina thickness and mean harmonic thickness of air-blood diffusion barrier were 23-29% higher. The prevalence of double-capillary profiles remained 82% higher. Absolute volumes of septal interstitium, collagen fibers, cells, and matrix were 32% higher; the relative volumes of other septal components and alveolar-capillary surface areas expressed as ratios to control values were up to 24% higher. Thus RA supplementation following right PNX modestly and persistently enhanced long-term alveolar-capillary structural dimensions, especially the deposition of interstitial and connective tissue elements, in such a way that caused a net increase in barrier resistance to diffusion without improving lung mechanics or gas exchange.  相似文献   
140.
The mammalian diaphragm is composed of two separate muscles (costal and crural) connected by a central tendon that serves as a piston head for drawing air into the lungs. The two muscles are described as having different embryological origins, segmental innervations, and mechanical functions [De Troyer A, Sampson M, Sigrist S, and Macklem PT. Science 213: 237-238, 1981; De Troyer A, Sampson M, Sigrist S, and Macklem PT. J Appl Physiol 53: 30-39, 1982]. On the basis of regional blood flow measurements, the two muscles appear to be nonuniformly recruited at rest, but we anticipated that the two muscles would become uniformly recruited at heavy exercise to efficiently support the high energy requirements of ventilation. We used fluorescent microspheres to measure regional blood flow within the two muscles as an index of muscle recruitment from rest to heavy treadmill exercise in well-trained foxhounds. However, the heterogeneity of blood flow at rest persisted as exercise workloads were increased. Blood flow per gram of muscle remained twofold greater in ventral than dorsal regions of both muscles from rest to heavy exercise. This pattern was matched by a twofold greater regional mechanical advantage in ventral than dorsal regions of the two muscles measured anatomically. Hence blood flow was preferentially and efficiently distributed to those regions capable of generating the greatest inspiratory power independent of muscle mass. The two muscles were recruited from rest to heavy exercise as a single functional unit, not as two muscles under separate control.  相似文献   
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