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991.
Haemophilus influenzae from patients with chronic obstructive pulmonary disease exacerbation induce more inflammation than colonizers 总被引:3,自引:0,他引:3
Chin CL Manzel LJ Lehman EE Humlicek AL Shi L Starner TD Denning GM Murphy TF Sethi S Look DC 《American journal of respiratory and critical care medicine》2005,172(1):85-91
RATIONALE: Airway infection with Haemophilus influenzae causes airway inflammation, and isolation of new strains of this bacteria is associated with increased risk of exacerbations in patients with chronic obstructive pulmonary disease (COPD). OBJECTIVE: To determine whether strains of H. influenzae associated with exacerbations cause more inflammation than strains that colonize the airways of patients with COPD. METHODS: Exacerbation strains of H. influenzae were isolated from patients during exacerbation of clinical symptoms with subsequent development of a homologous serum antibody response and were compared with colonization strains that were not associated with symptom worsening or an antibody response. Bacterial strains were compared using an in vivo mouse model of airway infection and in vitro cell culture model of bacterial adherence and defense gene and signaling pathway activation in primary human airway epithelial cells. RESULTS: H. influenzae associated with exacerbations caused more airway neutrophil recruitment compared with colonization strains in the mouse model of airway bacterial infection. Furthermore, exacerbation strains adhered to epithelial cells in significantly higher numbers and induced more interleukin-8 release after interaction with airway epithelial cells. This effect was likely mediated by increased activation of the nuclear factor-kappaB and p38 mitogen-activated protein kinase signaling pathways. CONCLUSIONS: The results indicate that H. influenzae strains isolated from patients during COPD exacerbations often induce more airway inflammation and likely have differences in virulence compared with colonizing strains. These findings support the concept that bacteria infecting the airway during COPD exacerbations mediate increased airway inflammation and contribute to decreased airway function. 相似文献
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Rajagopalan S Pfenninger D Kehrer C Chakrabarti A Somers E Pavlic R Mukherjee D Brook R D'Alecy LG Kaplan MJ 《Arthritis and rheumatism》2003,48(7):1992-2000
OBJECTIVE: To compare microvascular and macrovascular functions in a cohort of patients with primary and secondary Raynaud's phenomenon (RP) who were matched for demographic, risk factor, and severity profiles. METHODS: Forty patients with primary or secondary RP matched for vascular risk factors and severity scores underwent testing of endothelial function and cold pressor responsiveness of the brachial artery. Microvascular perfusion of the digital vasculature was assessed using laser Doppler fluxmetry in response to reactive hyperemia. Plasma was assayed for endothelin 1 (ET-1), asymmetric dimethylarginine (ADMA), intercellular adhesion molecule 1, vascular cell adhesion molecule 1 (VCAM-1), and monocyte chemoattractant protein 1 (MCP-1). RESULTS: Patients with RP had abnormal vasoconstrictor responses to cold pressor tests (CPT) that were similar in primary and secondary RP. There were no differences in median flow-mediated and nitroglycerin-mediated dilation or CPT of the brachial artery in the 2 populations. Patients with secondary RP were characterized by abnormalities in microvascular responses to reactive hyperemia, with a reduction in area under the curve adjusted for baseline perfusion, but not in time to peak response or peak perfusion ratio. Plasma ET-1, ADMA, VCAM-1, and MCP-1 levels were significantly elevated in secondary RP compared with primary RP. There was a significant negative correlation between ET-1 and ADMA values and measures of microvascular perfusion but not macrovascular endothelial function. CONCLUSION: Secondary RP is characterized by elevations in plasma ET-1 and ADMA levels that may contribute to alterations in cutaneous microvascular function. 相似文献
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Parul Agarwa Bhawna Sharma Amreen Fatima Sanjay Kumar Jain 《Asian Pacific Journal of Tropical Biomedicine》2014,4(3):245-252
Convolvulus pluricaulis Choisy (C. pluricaulis) is a perennial herb that seems like morning glory. All parts of the herb are known to possess therapeutic benefits. The plant is used locally in Indian and Chinese medicine to cure various diseases. It is used in Ayurvedic formulation for chronic cough, sleeplessness, epilepsy, hallucinations, anxiety etc. Based on the comprehensive review of plant profile, pharmacognosy, phytochemistry, pharmacological and toxicological data on the C. pluricaulis, there will be more opportunities for the future research and development on the herb C. pluricaulis. Information on the C. pluricaulis was collected via electronic search (using Pub Med, SciFinder, Google Scholar and Web of Science) and library search for articles published in peer-reviewed journals. Furthermore, information also was obtained from some local books on ethnopharmacology. This paper covers the literature, primarily pharmacological, from 1985 to the end of 2012. The C. pluricaulis is an important indigenous medicine, which has a long medicinal application for liver disease, epileptic disease, microbial disease, cytotoxic and viral diseases, central nervous system (CNS) disease in Ayurvedic medicine, traditional Chinese medicine and other indigenous medical systems. The isolated metabolites and crude extract have exhibited a wide of in vitro and in vivo pharmacological effect, including CNS depression, anxiolytic, tranquillizing, antidepressant, antistress, neurodegenerative, antiamnesic, antioxidant, hypolipidemic, immunomodulatory, analgesic, antifungal, antibacterial, antidiabetic, antiulcer, anticatatonic, and cardiovascular activity. A chemical study of this plant was then initiated, which led to the isolation of carbohydrats, proteins, alkaloids, fatty acids, steroids, coumarins, flavanoids, and glycosides as active chemicals that bring about its biological effects. A series of pharmacognostical studies of this plant show that it is a herb, its stem and leaves are hairy, more over it has two types of stomata, anisocytic and paracytic. A herb, C. pluricaulis has emerged as a good source of the traditional medicine for the treatment of liver disease, epileptic disease, microbial disease, cytotoxic and viral diseases, and CNS disease. Pharmacological results have validated the use of this species in traditional medicine. All the parts of the herb are known to possess therapeutic benefits. Expansion of research materials would provide more opportunities for the discovery of new bioactive principles from C. pluricaulis. 相似文献
997.
Mihai G Winner MW Raman SV Rajagopalan S Simonetti OP Chung YC 《Journal of magnetic resonance imaging : JMRI》2012,35(2):449-455
Purpose:
To evaluate the use of a T2‐weighted SPACE sequence (T2w‐SPACE) to assess carotid stenosis via several methods and compare its performance with contrast‐enhanced magnetic resonance angiography (ceMRA).Materials and Methods:
Fifteen patients with carotid atherosclerosis underwent dark blood (DB)‐MRI using a 3D turbo spin echo with variable flip angles sequence (T2w‐SPACE) and ceMRA. Images were coregistered and evaluated by two observers. Comparisons were made for luminal diameter, luminal area, degree of luminal stenosis (NASCET: North American Symptomatic Endarterectomy Trial; ECST: European Carotid Surgery Trial, and area stenosis), and vessel wall area. Degree of NASCET stenosis was clinically classified as mild (<50%), moderate (50%–69%), or severe (>69%).Results:
Excellent agreement was seen between ceMRA and T2w‐SPACE and between observers for assessment of lumen diameter, lumen area, vessel wall area, and degree of NASCET stenosis (r > 0.80, P < 0.001). ECST stenosis was consistently higher than NASCET stenosis (48 ± 14% vs. 24 ± 22%, P < 0.001). Area stenosis (72 ± 2%) was significantly higher (P < 0.001) than both ESCT and NASCET stenosis.Conclusion:
DB‐MRI of carotid arteries using T2w‐SPACE is clinically feasible. It provides accurate measurements of lumen size and degree of stenosis in comparison with ceMRA and offers a more reproducible measure of ECST stenosis than ceMRA. J. Magn. Reson. Imaging 2012;449‐455. © 2011 Wiley Periodicals, Inc. 相似文献998.
999.
Sakti Prasad Das Sudhakar Pradhan Shankar Ganesh Pabitra Kumar Sahu Ram Narayan Mohanty Sanjay Kumar Das 《Indian Journal of Orthopaedics》2012,46(2):221-228
Background:
Severe crouch gait in adolescent cerebral palsy is a difficult problem to manage. The patients develop loading of patellofemoral joint, leading to pain, gait deviation, excessive energy expenditure and progressive loss of function. Patella alta and avulsion of patella are the other complications. Different treatment options have been described in the literature to deal with this difficult problem. We evaluated outcome of supracondylar femoral extension osteotomy (SCFEO) and patellar tendon advancement (PTA) in the treatment of crouch gait in patients with cerebral palsy.Materials and Methods:
Fourteen adolescents with crouch gait were operated by SCFEO and PTA. All subjects were evaluated pre and postoperatively. Clinical, radiographic, observational gait analysis and functional measures were included to assess the changes in knee function.Results:
Cases were followed up to 3 years. The patients walked with increased knee extension and improvement in quadriceps muscle strength. Knee pain was decreased and improvements in functional mobility and radiologic improvement were found.Conclusion:
SCFEO and PTA for adolescent crouch gait is effective in improving knee extensor strength, reducing knee pain and improving function. 相似文献1000.