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PURPOSE: The purpose of this study was to determine the role of matrix metalloproteinases (MMP) in Pseudomonas aeruginosa keratitis. METHODS: Gene array and selective real-time PCR examined MMP expression in the cornea of susceptible (C57BL/6, B6) versus resistant (BALB/c) mice before and after infection; zymography tested enzyme activity for MMP-2 and -9. Clinical score, Langerhans cell (LC), and Neutrophil (PMN) quantitation were done in recombinant (r) MMP-9, antibody neutralized, and MMP-9(-/-) mice. The chemotactic potential of MMP-9 was tested in a Boyden chamber assay; light and transmission microscopy and immunostaining for collagen IV and MMP-9 were used to examine the effects and the source of MMP-9 after infection. ELISA was used to assess IL-1beta and MIP-2 levels. RESULTS: Gene array (confirmed by PCR) revealed sixfold more MMP-9, and zymography showed greater enzyme activity in the infected cornea of B6 over BALB/c mice. rMMP-9 injection of BALB/c mice enhanced, whereas MMP-9 antibody neutralization in B6 mice and its absence in MMP-9(-/-) mice decreased corneal disease. MMP-9(-/-) and antibody neutralized mice had fewer LCs in cornea; rMMP-9-treated mice had more. A myeloperoxidase (MPO) assay showed a similar pattern for PMN. MMP-9 was not chemotactic for LC or PMN. The basement membrane was more intact in MMP-9(-/-) over wild-type infected mice and correlated with staining for collagen IV; PMN was a source of MMP-9. IL-1beta and MIP-2 were increased in rMMP-9 but decreased in MMP-9 antibody neutralized and MMP-9(-/-) over control groups. CONCLUSIONS: MMP-9 regulates immune function in cornea by proteolysis, potentiating P. aeruginosa keratitis by degrading collagen IV and upregulating chemotactic cytokines/chemokines IL-1beta and MIP-2.  相似文献   
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OBJECTIVE: This study applied a well-known, recently revised theoretical model of healthcare access and utilization, the Behavioral Model for Vulnerable Populations, to examine the relationship between access to care and utilization of eye care services among a multiethnic, predominately minority sample of residents from low-income public housing. DESIGN: Population-based, cross-sectional survey of community sample. SETTING: Urban Public Housing Communities in Los Angeles County, California. PARTICIPANTS: A geographically defined stratified random sample of 152 residents (86% Latino or African American) 40 years of age and older from three urban public housing communities. RESULTS: Only 62% of our sample of persons 40 years and older had received an eye examination within the past 2 years. Sixty-one percent of participants reported having vision care coverage. Yet, one out of four respondents claimed that no health care provider had ever told them that they needed an eye-examination. Applying multiple logistic regression and controlling for a number of predisposing, enabling, and need-for-care characteristics, the variables 1) receiving advice from health care providers for eye examination (OR = 3.9, p < 0.01), 2) possessing coverage for eye-care (OR = 3.2, p < 0.01), and 3) having regular and continuity of medical care (OR = 2.4, p < 0.01) remained significant predictors of eye-examination within the past 2 years. CONCLUSION: This study documents significantly diminished utilization of eye care services relative to recommended guidelines for a low-income, predominately minority sample of residents from public housing communities. We documented no association between presence of diabetes or hypertension and recency of eye examination. Affordability, continuity, and regular sources of care, as well as receiving physician advice, remain the core factors significantly associated with receiving vision care. These results underscore the need for continued efforts to ensure that the medically underserved minority have access to vision care services. These findings also point toward the urgent need for educational and motivational interventions that encourage health care providers serving underserved communities to promote eye examination, particularly among diabetic patients, hypertensive patients, and other individuals at risk for eye-related disease and complications.  相似文献   
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Lobular capillary hemangioma (LCH or pyogenic granuloma) is a benign vascular proliferation. It has features of a capillary hemangioma with a circumscribed aggregation of capillaries arranged in one or more lobules. It occurs in humans and rarely in animals. The present report describes pathologic findings of a pyogenic granuloma occurence on the mandibular gingiva of a Holstein calf. Grossly, the mass was polyploidy, reddish- to brown-colored, and pedunculated with an ulcerated surface that covered with a layer of white to yellow exudate. Histopathologic examination revealed characteristic lobular proliferation capillaries in a loose stroma. The stroma was formed from numerous fibroblasts, fibrocytes, and slender collagen fibers. It was edematous with scattered of mononuclear cells. Infiltration of neutrophils were visible adjust to the ulcerated area. Remarkable involution was seen after washing with povidone iodine 1%. This tumorlike lesion was diagnosed as LCH based on gross appearance, histopathologic features, and treatment by mouthwash povidone iodine.  相似文献   
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A 24-h urinary protein is a standard way to diagnose lupus nephritis. Assessment of protein–creatinine (Pr–Cr) ratio in morning spot urine is a valuable method in diabetic patients but not use in systemic lupus erythematous (SLE) patients routinely. In this study Pr–Cr ratio in spot urine was compare with 24-h urine protein; if they have valuable correlation we can use this test instead of 24-h urinary protein. The aim of this study was to evaluate the correlation of spot urine Pr–Cr ratio for prediction of significant proteinuria (≥300 mg/24 h) in patients with SLE. A cross-section study was conducted in 74 hospitalized women with SLE. The correlation between Pr–Cr in first morning urine specimens and urinary protein excretion in 24-h collections were analyzed. Correlation between Pr–Cr ratio in spot morning urine specimens and urinary protein excretion in 24-h collections was significant (P < 0.0001, r = 0.83). A high correlation and precision of agreement were demonstrated between the two methods of assessment proteinuria in lupus patients. The difference between the two methods was less than the biological variability in the protein excretion and its measurement, enabling the methods to be used interchangeably creatinine ratio in spot morning urine samples is a precise indicator of proteinuria in patients with lupus nephritis and represents a simple and inexpensive procedure in establishing severity of proteinuria in patients with SLE.  相似文献   
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OBJECTIVES: To determine the prevalence and correlates of HIV-1 infection among community-based injecting drug users (IDUs) in Tehran, Iran. METHODS: In October 2004, 213 IDUs were recruited from a drop-in center and its neighboring parks and streets in Tehran. Participants were interviewed using a structured questionnaire regarding their sociodemographics and HIV risk characteristics, and specimens of oral mucosal transudate were collected and tested for HIV-1 antibodies. Data were analyzed using chi and multiple logistic regression to estimate odds ratios (OR) and 95% confidence intervals (CI). RESULTS: The prevalence of HIV-1 infection was 23.2% (48 of 207) among male injecting drug users. In the multivariable analysis, a history of shared drug injection inside prison (OR, 2.45; 95% CI, 1.01-5.97) and that of multiple incarcerations (OR, 3.13; 95% CI, 1.08-9.09) were associated with significantly higher prevalence of HIV-1 infection. CONCLUSIONS: The prevalence of HIV-1 infection has reached an alarming level among IDUs in Tehran, with incarceration-related exposures revealed to be the main correlates of HIV-1 infection. Urgent and comprehensive harm reduction programs for drug users in prison and those in the community in Tehran are of prime importance to prevent further transmission of HIV infection.  相似文献   
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We determined the frequency of clinical thyroid ophthalmopathy in Iranian patients. This cross-sectional study was performed at the Endocrinology Institute of Tehran University of Medical Sciences. All patients with documented thyroid disorders from September 2003 to July 2005 were recruited. Eye examinations included evaluation of soft tissue changes, measurement of proptosis, lid width, lagophthalmos, evaluation of eye muscle function, and determination of visual acuity. The activity of ophthalmopathy was scored according to the NOSPECS scale. Among 851 visited patients, 303 cases had thyroid eye disease (TED). The nature of the ophthalmopathy breaks down as follows: 53.4% were hypothyroid (9.3% Hashimoto disease), 5.5% euthyroid and 41.1% had Graves' disease. The prevalence of TED in males was 60% which was nearly 2 times the prevalence of TED in females. There was a significant relationship between presentation of TED and active smoking of the patients (P<0.0001) while no significant relationship with passive smoking was obtained (P=0.181). The most common clinical sign of TED in descending order respectively were proptosis with 63.4%, soft tissue involvement (40.9%), extraocular muscle involvement (22.1%), corneal involvement (12.9%) and optic nerve dysfunction (6.3%). Myasthenia gravis occurred in only 2 patients. In the logistic regression, occurrence of TED was influenced by cardiovascular disease (OR=5.346), Graves' disease (OR=47.507), radioiodine therapy (OR=2.590), and anti-thyroid medications (OR=0.650). Thyroid ophtalmopathy (orbitopathy) is a matter of important health concern among patients with thyroid disorder. Since TED occurred with a high prevalence in all thyroid states, a close collaboration between endocrinologists and ophthalmologists along with timely referrals of patients with any eye complaint is deemed necessary. Also smoking was the most important risk factor for developing TED. Therefore, it is advisable to raise awareness and to strongly encourage smokers with thyroid disorders to quit smoking.  相似文献   
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We compared the prevalence of exposure to violence across different types of alcohol consumed and the association between the type of alcohol consumed and exposure to violence. A cross-sectional analysis of data collected from a sample of 295 Emergency Department (ED) patients identified as having an alcohol problem. Outcome measure include exposure to violence, and the main study predictor was “type of alcoholic drink” including: malt liquor beer (MLB), regular beer, wine cooler, wine, fortified wine or hard liquor. Using logistic regression analysis, ED patients who drank MLB in combination with other types of alcohol increased their odds of being both threatened and physically attacked by 8.5 compared to ED patients who drank other types of alcohol. Being female increased the odds of being both threatened and physically attacked by 2.5 and using illicit drugs increased the odds by 3.8. Analysis of covariance and estimated marginal means revealed that ED patients who only drank MLB had a higher exposure to violence compared to non-MLB drinkers, and that female illicit drug users who drank MLB in combination with other types of alcohol had the highest exposure to violence. MLB was identified as a predictor of the amount of exposure to violence and in particular, that the use of malt liquor beer in combination with other types of alcohol increased the risk of being both threatened and physically attacked. Implications for ED and community interventions are suggested.  相似文献   
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