Search PubMed⌕ Search

Biomedical subjects

B Munoz

Publications and source records attributed to B Munoz.

At least 19 recordsLinked to original sources
PubMed2006

The association between epilation and corneal opacity among eyes with trachomatous trichiasis.

AIM: To examine the association between epilation and corneal opacity (CO) among trichiasis patients presenting for surgery. METHODS: Cross sectional data from the STAR trial were utilised. Patients presenting for trichiasis surgery in Wolayta Zone, Ethiopia, were evaluated for current trichiasis status. Number of inturned lashes, evidence of epilation, level of entropion, trichiasis duration, and CO were collected. The primary outcome was prevalence of CO, stratified by entropion and epilation status. RESULTS: Approximately 10% of eyes with mild entropion had CO, regardless of epilation status. Among eyes with moderate entropion, epilated eyes were less likely to have CO than non-epilated eyes (21% v 34% p = 0.002). The same association was seen in eyes with severe entropion: 43% of epilated eyes while 74% of non-epilated eyes had CO (p<0.0001). Presence of CO increased with age. Adjusted models showed a protective effect of epilation in eyes with moderate or severe entropion (OR: 0.51; 95% CI: 0.32 to 0.83 and OR: 0.24; 95% CI: 0.13 to 0.45, respectively). Among eyes with mild entropion there was no difference in the prevalence of CO comparing eyes that were epilated with those that were not epilated. CONCLUSION: Entropion was the most significant predictor of CO. Cross sectional associations suggest that epilation may not be helpful for eyes with mild entropion, but may offer protection against CO in eyes with moderate to severe entropion. Epilation should not be a substitute for trichiasis surgery, however, as 43% of eyes with severe entropion that were epilated still had CO.

Corneal Opacity↗
PubMed2005

Characteristics of trichiasis patients presenting for surgery in rural Ethiopia.

AIMS: To determine the characteristics of trichiasis patients presenting for surgery in Wolayta Zone of Ethiopia. METHODS: Patients referred for trichiasis surgery by community health agents were evaluated by trained integrated eye care workers (IECWs) for the presence of trichiasis, locations of inturned lashes, severity of trichiasis, corneal opacity, and visual acuity. RESULTS: 1635 individuals with trichiasis presented for surgery. 82% had bilateral trichiasis; 91% of patients reported trichiasis duration of >2 years. Epilation was practised by over three fourths of the study subjects. A high proportion of patients tested positive for ocular Chlamydia trachomatis at presentation. 17% had monocular blindness and 8% were binocularly blind. Corneal opacity was highly associated with the trichiasis duration and severity and visual loss was associated with corneal opacity. CONCLUSION: Severe trichiasis reflects the magnitude of the trachoma problem in Ethiopia. Visual impairment due to trichiasis is highly associated with disease severity and duration. Early intervention to correct trichiasis before it become severe is recommended to prevent visual impairment.

Adult↗
PubMed2004

Dynamics of {beta}-amyloid reductions in brain, cerebrospinal fluid, and plasma of {beta}-amyloid precursor protein transgenic mice treated with a {gamma}-secretase inhibitor.

gamma-Secretase inhibitors are one promising approach to the development of a therapeutic for Alzheimer's disease (AD). gamma-Secretase inhibitors reduce brain beta-amyloid peptide (Abeta), which is believed to be a major contributor in the etiology of AD. Transgenic mice overexpressing the human beta-amyloid precursor protein (APP) are valuable models to examine the dynamics of Abeta changes with gamma-secretase inhibitors in plaque-free and plaque-bearing animals. BMS-299897 2-[(1R)-1-[[(4-chlorophenyl)sulfony](2,5-difluorophenyl)amino]ethyl]-5-fluorobenzenepropanoic acid, a gamma-secretase inhibitor, showed dose- and time dependent reductions of Abeta in brain, cerebrospinal fluid (CSF), and plasma in young transgenic mice, with a significant correlation between brain and CSF Abeta levels. Because CSF and brain interstitial fluid are distinct compartments in composition and location, this correlation could not be assumed. In contrast, aged transgenic mice with large accumulations of Abeta in plaques showed reductions in CSF Abeta in the absence of measurable changes in plaque Abeta in the brain after up to 2 weeks of treatment. Hence, CSF Abeta levels were a valuable measure of gamma-secretase activity in the central nervous system in either the presence or absence of plaques. Transgenic mice were also used to examine potential side effects due to Notch inhibition. BMS-299897 was 15-fold more effective at preventing the cleavage of APP than of Notch in vitro. No changes in the maturation of CD8(+) thymocytes or of intestinal goblet cells were observed in mice treated with BMS-299897, showing that it is possible for gamma-secretase inhibitors to reduce brain Abeta without causing Notch-mediated toxicity.

Aging↗
PubMed2004

Gender equity and trichiasis surgery in the Vietnam and Tanzania national trachoma control programmes.

AIMS: To calculate the gender distribution of trichiasis cases in trachoma communities in Vietnam and Tanzania, and the gender distribution of surgical cases, to determine if women are using surgical services proportional to their needs. METHODS: Population based data from surveys done in Tanzania and Vietnam as part of the national trachoma control programmes were used to determine the rate of trichiasis by gender in the population. Surgical records provided data on the gender ratio of surgical cases. RESULTS: The rates of trichiasis in both countries are from 1.4-fold to sixfold higher in females compared to males. In both countries, the female to male rate of surgery was the same or even higher than the female to male rate of trichiasis in the population. CONCLUSIONS: These data provide assurance of gender equity in the provision and use of trichiasis surgery services in the national programmes of these two countries. Such simple analyses should be used by other programmes to assure gender equity in provision and use of trichiasis surgery services.

Eyelashes↗
PubMed2004

Cataract surgery and subtype in a defined, older population: the SEECAT Project.

AIM: To describe the distribution of cataract subtypes present before surgery among a defined population of older, bilaterally pseudophakic individuals. METHODS: This was a cohort study of bilaterally pseudophakic individuals participating in the Salisbury Eye Evaluation (SEE), and their locally resident siblings. Subjects underwent slit lamp and retroillumination photography and grading using the Wilmer Cataract Grading System. For all individuals determined to be bilaterally pseudophakic, an attempt was made to determine for each eye the type(s) of cataract present before surgery, based on previous SEE photographs (for SEE participants) and/or medical records obtained from the operating ophthalmologist (for both SEE participants and their siblings). RESULTS: The mean age of 223 participants providing data in this study was 78.7 (SD 5.2) years, 19.3% of subjects were black and 60.1% female. The most common surgically removed cataract subtype in this population was pure nuclear (43.5%), followed by nuclear combined with posterior subcapsular cataract (PSC) (20.6%), and nuclear combined with cortical (13.9%); less common types were pure cortical (4.9%), pure PSC (4.5%), and PSC combined with cortical (2.7%). Factors such as sex and source of lens data (study photograph versus clinical record) did not significantly affect the distribution of lens opacity types, while PSC was significantly (p = 0.01) more common among younger people and nuclear cataract was significantly (p = 0.001) more common among white compared to black people. CONCLUSION: Epidemiological studies have suggested that the different subtypes of cataract are associated with different risk factors. As studies begin to identify new prevention strategies for cataract, it would appear likely that different strategies will be efficacious against different types of cataract. In this setting, it will be helpful to know which cataract types are most frequently associated with surgery. Among this older, majority white population, nuclear cataract showed a clear predominance among individuals having undergone surgery in both eyes. This may be contrasted with both clinic and population based studies of younger people, which have generally found PSC cataract to predominate.

Age Distribution↗
PubMed2001

Hormone replacement therapy and lens opacities: the Salisbury Eye Evaluation project.

BACKGROUND: Data suggest a possible protective effect against lens opacity with use of hormone replacement therapy (HRT). However, no agreement exists on which opacity type is affected, and more exploration of the additional role of endogenous estrogen exposure is warranted. OBJECTIVE: To determine whether HRT and the prevalence of different lens opacity types are associated after controlling for endogenous estrogen exposure. DESIGN AND SETTING: Salisbury Eye Evaluation population-based prevalence survey of residents in an eastern US city. PARTICIPANTS: One thousand two hundred thirty-nine women aged 65 through 84 years. MAIN OUTCOME MEASURES: Nuclear, cortical, and posterior subcapsular opacity. RESULTS: We found a protective association between nuclear opacity and current (odds ratio [OR], 0.5; 95% confidence interval [CI], 0.3-0.7) and recent (OR, 0.4; 95% CI, 0.3-0.7) HRT use. Increasing number of births in younger women was also protective (test of trend, P =.05). Past HRT use protected against nuclear opacity only in women who had never been pregnant (OR, 0.2; 95% CI, 0.1-0.7). Past (OR, 0.2; 95% CI, 0.1-0.7) and current (OR, 0.3; 95% CI, 0.1-0.9) HRT use were associated with a lower prevalence of posterior subcapsular opacity. CONCLUSION: A protective association between the use of HRT and nuclear and posterior subcapsular opacities is reported, which should be confirmed in prospective studies.

Aged↗
PubMed2001

The prevalence of glaucoma in a population-based study of Hispanic subjects: Proyecto VER.

OBJECTIVE: To determine the prevalence of glaucoma in a population-based sample of Hispanic adults older than 40 years. METHODS: Using 1990 census data for Arizona, groups of persons living in sections of the city in Nogales and Tucson were randomly selected with a probability proportional to the Hispanic population older than 40 years. We tried to recruit all eligible adults in homes with 1 self-described Hispanic adult. Detailed ocular examinations at a local clinic included visual acuity testing, applanation tonometry, gonioscopy, an optic disc evaluation, and a threshold visual field test. Open-angle glaucoma (OAG) was defined using a proposed international system for prevalence surveys, including threshold visual field defect and optic disc damage. Angle-closure glaucoma was defined as bilateral appositional angle closure, combined with optic nerve damage (judged by field and disc as for OAG). RESULTS: Examinations were conducted in 72% (4774/6658) of eligible persons, with a 1.97% prevalence (95% confidence interval, 1.58%-2.36%) of OAG (94 persons). The age-specific OAG prevalence increased nonlinearly from 0.50% in those aged 41 to 49 years to 12.63% in those 80 years and older. Angle-closure glaucoma was detected in 5 persons (0.10%). Sex, blood pressure, and cigarette smoking were not significant OAG risk factors. Only 36 (38%) of the 94 persons with OAG were aware of their OAG before the study. Screening results with an intraocular pressure higher than 22 mm Hg (in the eye with a higher pressure) would miss 80% of the OAG cases. CONCLUSIONS: The prevalence of OAG in Hispanic persons was intermediate between reported values for white and black persons. The prevalence increased more quickly with increasing age than in other ethnic groups. Glaucoma was the leading cause of bilateral blindness.

Adult↗
PubMed2001

Psychometric properties of the 25-item NEI-VFQ in a Hispanic population: Proyecto VER.

PURPOSE: To assess the psychometric properties of the NEI-VFQ-25 in a population-based study of older Hispanic persons living in the United States, explore other demographic factors that affect participant response, and observe the comparability of the Spanish and English versions of the instrument. METHODS: A sample of randomly selected block groups in Tucson and Nogales, Arizona, were selected for study. Participants were interviewed at home; a majority of the interviews were conducted in Spanish. The home interview included questions from the NEI-VFQ-25 and HHANES: Presenting acuity was done using ETDRS methodology, followed by a standardized eye examination by an ophthalmologist. The authors analyzed the internal consistency of the NEI-VFQ-25 responses using Cronbach's alpha coefficient and the construct validity by assessing the relationship between presenting acuity and scale scores, adjusting for age and gender. A second model was also explored to determine whether other demographic variables affected scale scores; differences in reporting between the Spanish and English versions was observed in this model, used in a subset of the population that minimized interviewer effect. RESULTS: Of the 4774 participants in the study, 99.7% had completed questionnaires, not completed by proxy. The highest nonresponse rate occurred in the Driving scale, with 25% of participants not driving for reasons other than problems with vision. Internal consistency was high, with Cronbach alpha ranging between 0.65 and 0.86 for scales with multiple items. Adjusting for age and gender, those with presenting acuity worse than 20/40 scored significantly lower than those with presenting acuity 20/40 or better, for all scales. The demographic variables with the most consistent association across the NEI-VFQ-25 scales were presenting acuity, income, and gender. No significant differences in reporting were found between the Spanish and English versions of the questionnaire in the subset of the population. CONCLUSIONS: In this study of Hispanic people age 40 years or older, the NEI-VFQ-25 was sensitive to presenting acuity and other demographic variables, such as age, gender, and income. The findings from this psychometric analysis provide evidence of the reliability and validity of some of the scales in the 25-item NEI-VFQ when used among people with a range of visual acuity level, providing other explanatory variables are also considered.

Activities of Daily Living↗
PubMed2000

Resin activation capture technology: libraries from stabilized acyl-pyridinium on solid support.

REsin Activation/Capture APproach or REACAP Technology, a novel approach to the synthesis of compound libraries, capitalizes on the formation and retention of a resin-bound reactive intermediate, which can be subsequently transformed into a stable, covalently attached molecule. Any unreacted "reactive intermediate" is quenched and removed from the resin upon work-up, leaving only the desired product on the solid support. In contrast to more traditional solid-supported chemistry that must address issues such as resin-loading, capping of unreactive functionalized moieties, and reaction yields, REACAP offers an attractive alternative with the focus more on the purity of the released products and less on yield. In an endeavor to generate truly non-peptide leads, we describe herein the synthesis of N-acyl-2-substituted-dihydro-4-pyridones, dihydro-4-pyridones, 4-ketopiperidines, tetrahydropyridines, and 2-acyl-3,7,8-substituted-5-oxo-2-azabicyclo[2.2.2]octane and triaza analogs using REACAP Technology.

Databases as Topic↗
PubMed1999

Determination of risk factor associations with questionnaire outcomes: a methods case study.

Increasingly in biomedical studies, health status is inferred through a series of questionnaire item responses. Challenges for analyzing associations between such responses and risk factors include multiplicity-many indicators must be combined to derive summary statements about health status, and measurement error-persons' self-report fluctuates due to causes other than substantive health changes. In order to deal with these challenges, the authors propose a strategy which comprises three methods: 1) score the item responses, then regress the score on predictors; 2) regress each item response on predictors, accounting for within-person associations; and 3) summarize and analyze the item responses jointly, using a latent variable model. The authors develop modeling and diagnostic procedures for method 3. They then show how the three-method analytic strategy can be used to solve the problem of determining which aspects of vision are associated with self-reported functioning in activities that require seeing at a distance. They demonstrate that methods 2 and 3 illuminate basic findings from method 1 by adding specificity, describing patterns as well as severities of health impairments, and identifying isolated items that relate to risk factors differentially than others. They conclude that the three-method strategy specifies how risk factors determine questionnaire-based health outcomes substantially better than any of the methods in isolation.

Activities of Daily Living↗
PubMed1999

Characteristics of discrepancies between self-reported visual function and measured reading speed. Salisbury Eye Evaluation Project Team.

PURPOSE: Visual impairment is a risk factor for morbidity in the elderly and is often screened for by self-report. This study evaluates whether there are subsets for whom there is a discrepancy between self-reported and measured function. METHODS: The prevalence of a discrepancy between self-reported difficulty reading a newspaper and measured reading speed was determined in 2520 community-based men and women, aged 65 to 84 years, and the discrepant group characterized by polychotomous regression. RESULTS: Of subjects who reported minimal difficulty reading a newspaper, 10.8% (227/2107) read newsprint-sized text (0.21 degrees) more slowly than 80 words/min, a level previously shown to be necessary for sustained reading. Poor visual acuity, presence of psychiatric symptoms, and less satisfaction with vision were associated with being in the group that read slowly and reported difficulty with reading. Better cognition, better visual acuity, more years of education, white race, and fewer psychiatric symptoms were associated with being in the group that read more quickly and reported minimal difficulty. When reading the text size at which subjects read their fastest, only 2.6% of those with minimal difficulty remained discrepant. These individuals were more likely to have less education, be male, be African American, and have poorer cognitive status than those who did not remain discrepant. CONCLUSIONS: A subset of the elderly population have a substantial discrepancy between self-reported reading difficulty and measured reading speed. In some, this discrepancy may be based on underlying expectations and experiences, and in others it may represent a transition from no visual impairment to visual impairment.

Aged↗
PubMed1999

Digital image capture and automated analysis of posterior capsular opacification.

PURPOSE: To develop and validate a digital imaging and analysis technique for assessing the extent of posterior capsular opacification after cataract surgery. METHODS: Retroillumination images of the posterior capsule were obtained by using a digital camera mounted on a slit lamp. The images were analyzed using an available image analysis software program. The image acquisition and analysis techniques were tested for face validity, reproducibility, and the ability to detect progression of capsular opacity over time. RESULTS: Digital retroillumination images were obtained without patient discomfort. Automated analysis of images correlated well with clinical grading both at slit lamp examination and when looking at the images themselves (Spearman's correlation coefficient >0.7). Analysis of images taken at different times showed high reproducibility (intraclass correlation >0.9), and the system was able to identify progression of capsular opacity over a 2-year period with a mean increase of 15.8% in progressors versus an increase of 0.6% in nonprogressors (P < 0.05). CONCLUSIONS: Digital retroillumination images of the posterior capsule can be obtained reliably, and automated analyses correlate well with clinical assessment. The system presented here uses commercially available instruments and software, and it is practical for use in longitudinal studies of posterior capsule opacification. It is reliable, easy to use, and can detect small changes in the percentage area covered by posterior capsule opacification over time.

Cataract↗
PubMed1999

Self-reported assessment of visual function in a population-based study: the SEE project. Salisbury Eye Evaluation.

PURPOSE: To report on the usefulness of the Activities of Daily Vision Scale (ADVS) questionnaire for assessing visual functioning, a population-based sample of elderly Americans. METHODS: The ADVS questionnaire was administered to a population-based sample of 2520 community-dwelling individuals 65 to 84 years of age in Salisbury, MD. Items and subscales were evaluated for internal consistency, item discrimination, and content validity. Published subscale groupings and item associations in our population were compared for coherence using correlation, factor, and cluster analyses. Whole-sample and race- and gender-specific analyses were conducted. External validity was explored by regressing ADVS scores on standard psychophysical vision measures. RESULTS: ADVS scores were skewed to high visual functioning levels; approximately 60% of the population had function scores of 95 or better (of a possible 100). The overall, night driving, and near vision scales were internally consistent and had strong item-subscale associations; the day driving and glare subscales were not acceptable regarding these properties. The far vision subscale was acceptably scalable but only weakly differentiated from the other subscales. Overall, night driving, near vision, and far vision scores were all statistically and independently associated with multiple psychophysical vision measures. Findings were consistent across race and gender subgroups. CONCLUSIONS: As assessed by the ADVS, reported visual functioning is high in our representative older population. The overall scale and selected subscales effectively distinguish persons along a spectrum of ability. They correlate with measures of visual impairment in a reasonable way and thus hold promise for risk factor investigations. The published day driving and glare subscales should be examined for relevance and consistency before being applied in population-based settings. Methods specific to population-based settings should be investigated for their ability to better elicit additional visual function dimensions and early visual disability.

Activities of Daily Living↗
PubMed1998

Prevalence of symptoms of dry mouth and their relationship to saliva production in community dwelling elderly: the SEE project. Salisbury Eye Evaluation.

OBJECTIVE: To estimate the prevalence of dry mouth symptoms and their correlation with saliva production in a population based sample of elderly people in the United States. METHODS: Two dry mouth questions were administered to and a modified Saxon test was performed in participants in a population based prevalence survey conducted among 2520 noninstitutionalized community dwelling residents of Salisbury, Maryland, aged 65-84 years. RESULTS: Seventeen percent reported having either dryness of mouth or waking at night feeling dryness in the mouth and needing to drink fluids often or all the time; 10.7% noted the former and 11.5% the latter. The prevalence of dry mouth symptoms increased with increasing age, was greater in women than men, and was greater in whites than blacks. The mean (SD) amount of saliva production was 2.38 (1.00) g/min; mean saliva production decreased with increasing age and was lower in women than men; no difference was noted by race. Persons with dry mouth symptom either often or all the time had significantly lower salivary production, even after adjustment for age and sex. CONCLUSION: Symptoms of dry mouth are common in the community dwelling elderly population, especially in white women, and correlate with decreased salivary production.

Age Factors↗
PubMed1997

Incidence estimates of late stages of trachoma among women in a hyperendemic area of central Tanzania.

The purpose of this study is to estimate 5-year incidences of conjunctival scarring and trichiasis, and 10-year incidence of corneal opacities due to trachoma, using prevalence data from a population sample of 6038 women living in a trachoma-hyperendemic area of central Tanzania. Previous surveys have documented the age-specific prevalence of scarring, trichiasis, and corneal opacities in women in hyperendemic areas. Using the age-stratified prevalences of these different clinical signs, corresponding incidence rates were estimated. Transition rates from one sign to the next were also obtained by restricting the risk group to only women with a specific trachoma sign. Thus, the 5-year incidence of trichiasis among women with conjunctival scarring, and the 10-year incidence of corneal opacities among women with trichiasis were estimated. Incidences of all the signs markedly increased with age. For scarring, 5-year incidence rates increased from 3.1% in the 15-19 age category to 14.3% for women between 55 and 59 years. The 5-year incidence of trichiasis ranged from 0.3% in the 15-19 age category to 7.5% in the age group 55-59. Corneal opacities due to trachoma were highest in the age group 45-54; the 10-year incidence increased to 2.8%. The 5-year incidence of trichiasis among only women with scars increased from 3.2% in the 15-19 age group to 15.1% in women in the 55-59 age group. Once trichiasis is present, almost one-third of the women below 35 and more than 40% of the women older than 45 will develop corneal opacities in a 10-year interval. These estimates are important in understanding the dynamics of progression of trachoma from conjunctival scarring to the potentially blinding signs of trichiasis and corneal opacities. They provide important information for planning adequate services in areas where trachoma is endemic and surgery for trichiasis is a key factor to avoid blindness from trachoma. They also provide clues to the pathogenesis that may be useful in the development of new methods of control.

Adolescent↗
PubMed1997

Assessing functional status: correlation between performance on tasks conducted in a clinic setting and performance on the same task conducted at home. The Salisbury Eye Evaluation Project Team.

BACKGROUND: Many studies of functional status in elderly people use performance-based measures. There is an underlying assumption that these measures reflect, at least for some tasks, functional abilities in everyday tasks carried out at home. The purpose of this study was to determine the correlation between tasks carried out in the clinic and at home, and the role of visual impairment in performance at either setting. METHODS: We compared the performance of 97 participants in the Salisbury Eye Evaluation (SEE) project at the clinic and at home on eight different tasks: semitandem stand, functional reach, stair climb and descend, inserting a plug, looking up and dialing a telephone number, and reading. RESULTS: The correlations were good for all tasks, with coefficients ranging from .52 to .86. Those with visual impairment were slightly more likely to perform better at home compared to the clinic, although the differences were statistically significant only for the reading task. The most important predictor of performance on any task in the home was performance on the task at the clinic, even after adjusting for age, race, sex, education, and visual impairment. Educational level and visual impairment were consistent predictors of performance in the home for most tests. CONCLUSIONS: We conclude that performances on standardized tasks in the clinic setting do correlate with similar tasks performed in the home, although the relationship is complicated in the presence of visual impairment.

Aged↗
PubMed1997

Function and visual impairment in a population-based study of older adults. The SEE project. Salisbury Eye Evaluation.

PURPOSE: The Salisbury Eye Evaluation (SEE) project investigates the impact of vision on functional status in a population-based sample of elderly persons. The prevalence of self-reports of functional status and the association with visual acuity loss are described. METHODS: A random sample of men and women 65 to 84 years of age from Salisbury, Maryland were recruited for home interviews and clinic examinations. Of the eligible sample, 78% responded to the home questionnaire and 65% responded to the questionnaire and the clinic examination. Binocular visual acuity of each person was measured using ETDRS charts and protocols. Questions were asked concerning activities of daily living, instrumental activities of daily living, physical function, social interaction, and activities of daily vision. Analyses of the association of presenting visual acuity worse than 20/40 with the measures of function were carried out and adjusted for age, race, and sex. RESULTS: All measures of functional status showed a decline with age; women and blacks were more likely to report difficulties. The age-adjusted proportions of those with visual impairment were not significantly different between men and women (7.2% versus 6.7%; P = 0.60). Black persons had almost twice the rate (10.4%) of white persons (5.6%; P < 0.001). Age, race, gender, and visual impairment were all significantly related to declines in functional status in multivariate models. CONCLUSIONS: Data on functional status in the project population were similar to national data and confirmed higher rates of disability in women and blacks. Binocular visual acuity worse than 20/40 appeared to have an impact on all the self-report measures of functional status. Further analyses on the interaction of vision with other comorbid conditions on function status clearly are indicated.

Activities of Daily Living↗