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Biomedical subjects

A Escalante

Publications and source records attributed to A Escalante.

At least 19 recordsLinked to original sources
PubMed2004

Lower limb arterial incompressibility and obstruction in rheumatoid arthritis.

BACKGROUND: Despite increased cardiovascular morbidity and mortality in rheumatoid arthritis, the peripheral arteries remain understudied. OBJECTIVE: To examine the lower limb arteries in age and sex matched, non-smoking subjects with and without rheumatoid arthritis. METHODS: The ankle-brachial index (ABI) was measured at the posterior tibial and dorsal pedal arteries. Arteries were classified as obstructed with ABI < or =0.9, normal with ABI >0.9 but < or =1.3, and incompressible with ABI >1.3. Multinomial logistic regression was used to estimate differences in ABI between patients and controls, adjusting for cardiovascular risk factors, rheumatoid arthritis manifestations, inflammation markers, and glucocorticoid dose. RESULTS: 234 patients with rheumatoid arthritis and 102 controls were studied. Among the rheumatoid patients, 66 of 931 arteries (7%) were incompressible and 30 (3%) were obstructed. Among the controls, three of 408 arteries (0.7%) were incompressible (p = 0.002) and four (1%) were obstructed (p = 0.06). At the person level, one or more abnormal arteries occurred among 45 rheumatoid patients (19%), v five controls (5%, p = 0.001). The greater frequency of arterial incompressibility and obstruction in rheumatoid arthritis was independent of age, sex, and cardiovascular risk factors. Adjustment for inflammation markers, joint damage, rheumatoid factor, and glucocorticoid use reduced rheumatoid arthritis v control differences. Most arterial impairments occurred in rheumatoid patients with 20 or more deformed joints. This subgroup had more incompressible (15%, p< or =0.001) and obstructed arteries (6%, p = 0.005) than the controls, independent of covariates. CONCLUSIONS: Peripheral arterial incompressibility and obstruction are increased in rheumatoid arthritis. Their propensity for patients with advanced joint damage suggests shared pathogenic mechanisms.

Adult↗
PubMed2003

Validating a computerized neuropsychological test battery for mixed ethnic lupus patients.

Patients with systemic lupus erythematosus (SLE) often show cognitive impairment on traditional neuropsychological tests; however, many of these tests are unsuitable for use with mixed ethnic populations. Computer-administered cognitive tests are promising, but have not been validated against traditional tests or with predominantly Hispanic samples. We gave 67 lupus patients a computer-administered test battery (Automated Neuropsychological Assessment Metrics--ANAM) and a battery of traditional neuropsychological tests. The two batteries were compared using correlation and multiple regression analyses. All patients were fluent in English, 54% were Hispanic and 13% were bilingual. Non-Hispanic patients were predominantly European American (37%). About 80% of patients were rated as impaired on traditional tests. Hispanics were younger, had less education and more current SLE disease activity than non-Hispanics; but did not differ in lifetime SLE-related organ damage or current steroid use. Hispanics and younger patients were more impaired on many of the traditional tests, while ANAM was not affected by Hispanic ethnicity or education. ANAM tests were moderately correlated with analogous traditional tests. Age and selected ANAM scores accounted for about 60% of the variance in the traditional battery. These results replicate the high prevalence of cognitive deficits in SLE found by others and suggest that computer-administered tests like ANAM may be useful for assessment of cognitive impairment in mixed-ethnic samples. Confounding variables such as age, education, English language fluency and prior experience with tests were identified and need to be controlled statistically or with comparison groups in future studies.

Adult↗
PubMed2002

Neuropsychiatric syndromes in lupus: prevalence using standardized definitions.

OBJECTIVE: The San Antonio Lupus Study of Neuropsychiatric Disease is a longitudinal study designed to characterize the spectrum of and important risk factors for specific neuropsychiatric systemic lupus erythematosus (NPSLE) syndromes. METHODS: Subjects must meet criteria for SLE and must be at least 18 years of age. A standardized medical history, neurologic, rheumatologic, and psychiatric examinations, computerized neuropsychological evaluation, and serologic testing are performed. RESULTS: This report is based on the first 128 subjects (120 women and 8 men) who completed the initial study visit. Data from this initial study visit were evaluated for the prevalence of NPSLE using the American College of Rheumatology case definitions for 19 NPSLE syndromes. One or more NPSLE syndromes were present in 80% of subjects: cerebrovascular disease (2, 2%; ischemic stroke); headaches (73, 57%); mononeuropathy (9, 8%; median 8, ulnar 1); movement disorder (1, 1%; chorea); neuropathy, cranial (2, 2%; trigeminal); polyneuropathy (29, 22%; sensorimotor); seizures (21, 16%; partial); anxiety disorder (27, 24%); major depressive-like episode (37, 28%); mood disorder with depressive features (21, 19%); mood disorder with manic features (3, 3%); mood disorder with mixed features (1, 1%); psychosis (6, 5%). In a subset of 67 patients who received standardized neuropsychological testing, 21% had normal results. In the remainder, the following levels of impairment were seen: 43% mild, 30% moderate, and 6% severe. CONCLUSIONS: The prevalence of NPSLE was high in this cohort of unselected patients with SLE. Headaches, cognitive dysfunction, and psychiatric disorders were the most common NPSLE syndromes seen. These results will be easily comparable to other studies also using standardized diagnostic criteria. However, the lack of ethnicity and language-matched normative neuropsychological data may make comparisons of cognitive dysfunction in SLE populations difficult.

Adult↗
PubMed2001

Lactic acid bacterial diversity in the traditional mexican fermented dough pozol as determined by 16S rDNA sequence analysis.

The lactic acid bacteria diversity of pozol, a Mexican fermented maize dough, was studied using a total DNA extraction and purification procedure and PCR amplification of 16S rDNA for gram-positive and related bacterial groups. Thirty-six clones were obtained and sequenced to 650 nucleotides. These partial sequences were identified by submission to the non-redundant nucleotide database of NCBI. The identified sequences were aligned with reference sequences of the closest related organisms. This analysis indicated that only 14 sequences were unique clones and these were identified as Lactococcus lactis, Streptococcus suis, Lactobacillus plantarum, Lact. casei, Lact. alimentarium, and Lact. delbruekii and Clostridium sp. Two non-ribosomal sequences were also detected. Unlike other environments analyzed with this molecular approach where many unidentified microorganisms are found, the identity of most sequences could be established as lactic acid bacteria, indicating that this is the main group among the gram-positive bacteria in pozol. Use of this molecular method permitted detection of lactic acid bacteria different from those previously isolated and identified by culture techniques

Clostridium↗
PubMed2001

Walking velocity in aged persons: its association with lower extremity joint range of motion.

OBJECTIVE: To measure the association between walking velocity and hip and knee flexion range, ethnic background, anthropometrics, comorbid pathologies, and coimpairments, in a sample of community-dwelling aged persons. METHODS: To reach our objective, we used data from the San Antonio Longitudinal Study of Aging (SALSA), a population-based cohort of Mexican American and European American persons aged 64 to 79. By fitting hierarchical regression models, we measured the variance in the walking velocity over 50 feet explained by hip and knee flexion range, adjusting for the combined influence of demographic and anthropometric variables, coexistent pathologic conditions, impairments, and the examiners who conducted the assessments. RESULTS: The average walking velocity among the 702 subjects for whom data were available was 73.6 meters per minute (range 20 to 121). Bivariate analyses revealed significant associations between walking velocity and age, sex, ethnic background, height, weight, presence of arthritis, diabetes mellitus, stroke, upper leg pain, peripheral vascular disease, left ventricular hypertrophy, and forced expiratory volume at 1 second. The correlation (r) between walking velocity and flexion range of the hip and knee were 0.40 and 0.35, respectively (P < or = 0.001 for each). Multivariate hierarchical models adjusting for demographic and anthropometric characteristics of the subjects, and examiner variation, revealed that hip and knee flexion range explained 6% of the variance in walking velocity. Adjusting for the presence of comorbid conditions and coimpairments reduced the variance attributable to hip and knee flexion range only slightly, to 5%. CONCLUSION: Hip and knee flexion range contribute significantly to walking velocity in the SALSA cohort of community-dwelling aged persons.

Age Factors↗
PubMed2001

High incidence of cardiovascular events in a rheumatoid arthritis cohort not explained by traditional cardiac risk factors.

OBJECTIVE: To compare the incidence of cardiovascular (CV) events in persons with rheumatoid arthritis (RA) with that in people from the general population, adjusting for traditional CV risk factors. METHODS: Two hundred thirty-six consecutive patients with RA were assessed for the 1-year occurrence of 1) CV-related hospitalizations, including myocardial infarction, stroke or other arterial occlusive events, or arterial revascularization procedures, or 2) CV deaths. Both outcomes were ascertained by medical records or death certificates. For comparison, we used CV events that occurred during an 8-year period among participants in an epidemiologic study of atherosclerosis and CV disease who were ages 25-65 years at study entry. We calculated the age- and sex-stratified incidence rate ratio (IRR) of CV events between the 2 cohorts and used Poisson regression to adjust for age, sex, smoking status, diabetes mellitus, hypercholesterolemia, systolic blood pressure, and body mass index. RESULTS: Of the 236 RA patients, 234 were observed for 252 patient-years, during which 15 CV events occurred. Of these, 7 incident events occurred during the 204 patient-years contributed by patients ages 25-65 years, for an incidence of 3.43 per 100 patient-years. In the comparison cohort, 4,635 community-dwelling persons were followed up for 33,881 person-years, during which 200 new events occurred, for an incidence of 0.59 per 100 person-years. The age- and sex-adjusted IRR of incident CV events associated with RA was 3.96 (95% confidence interval [95% CI] 1.86-8.43). After adjusting for CV risk factors using Poisson regression, the IRR decreased slightly, to 3.17 (95% CI 1.33-6.36). CONCLUSION: The increased incidence of CV events in RA patients is independent of traditional CV risk factors. This suggests that additional mechanisms are responsible for CV disease in RA. Physicians who provide care to individuals with RA should be aware of their increased risk of CV events and implement appropriate diagnostic and therapeutic measures.

Adult↗
PubMed2001

Epidemiology and impact of rheumatic disorders in the United States Hispanic population.

The emergence of a sizable Hispanic population in the US is a relatively recent historical phenomenon, and thus much is still unknown about this group of North Americans. Data from national surveys suggest small differences between Hispanic and non-Hispanic white populations in the age-adjusted prevalence of self-reported arthritic conditions. However, the rate of activity-limitation attributable to arthritis is higher among Hispanic patients. This likely reflects the poorer socioeconomic conditions and lack of health insurance that prevail among Hispanic populations, which may limit their access to rheumatologic care. Osteoporotic vertebral and hip fractures are less frequent, and proximal femoral mineral density is higher, in Hispanic individuals than in non-Hispanic white individuals. The mechanisms for these observations are currently under investigation. There have been no studies of the prevalence of osteoarthritis, rheumatoid arthritis, or systemic lupus erythematosus among Hispanic populations. However, important immunogenetic, clinical, and psychosocial differences between Hispanic and non-Hispanic patients in regard to rheumatoid arthritis and systemic lupus erythematosus have been reported. There is no published information on the prevalence or characteristics of other rheumatic diseases in the US Hispanic population. Emerging evidence suggests considerable underuse of certain health services for arthritis among Hispanic patients, likely due in part to socioeconomic factors. Further research is needed to determine whether biologic, cultural or psychosocial factors contribute to underuse as well. There is clearly a need for data on the prevalence and characteristics of arthritis and other rheumatic and musculoskeletal diseases in this emerging US population.

Arthritis↗
PubMed2000

Recipients of hip replacement for arthritis are less likely to be Hispanic, independent of access to health care and socioeconomic status.

OBJECTIVE: To compare the proportion of Hispanics among recipients of hip replacements for primary articular disorders, recipients of knee replacements for the same reason, and persons hospitalized for other reasons. METHODS: Twelve of the 17 accredited hospitals in Bexar County, Texas, in which hip or knee replacement surgery is performed permitted us to review their medical records. From 1993 through 1995, 3,100 elective, non-fracture-related, hip or knee replacements were performed. These individuals were matched by age, sex, hospital, and month of admission with 4,604 persons hospitalized for other reasons. Age, sex, ethnic background, type of medical insurance, median household income by zip code of residence, joint replaced, and surgical diagnosis were abstracted from the medical records. The validity of variables abstracted from the medical records was tested by comparison with self-report data in 115 patients interviewed prior to elective hip or knee replacement surgery. RESULTS: During the study period, 2,275 subjects had a total knee replacement and 825 had a total hip replacement. Recipients of hip replacements were significantly less likely to be Hispanic than were recipients of knee replacements (19.5% versus 29.9%; odds ratio [OR] 0.57, 95% confidence interval [95% CI] 0.46-0.71; P < or = 0.001) or persons hospitalized for other reasons (29.4% Hispanic; OR 0.67, 95% CI 0.55-0.81). The under-representation of Hispanics was more pronounced among persons undergoing hip replacement for osteoarthritis compared with recipients of knee replacements for the same disease (OR 0.48, 95% CI 0.37-0.62). This pattern persisted after adjusting for age, sex, type of medical insurance, and median household income by the zip code of residence. Concordance between medical records and self-report data on ethnic background was high (kappa = 0.93). CONCLUSION: Recipients of hip replacement are less likely to be Hispanic than are other hospitalized persons with a similar level of access to care. The reasons for this under-representation probably involve factors in addition to lack of access to health care and low socioeconomic status. Further research is needed to understand the nature of such factors.

Arthritis↗
PubMed2000

Symptoms of depression and psychological distress among Hispanics with rheumatoid arthritis.

OBJECTIVE: To explore the roles played by Hispanic ethnic background and acculturation to the mainstream English language culture of the United States in the depressive symptoms and mental health of rheumatoid arthritis (RA) patients. METHODS: Members of a consecutive cohort of patients with RA were studied cross-sectionally. All underwent a comprehensive clinical and psychosocial evaluation. Depressive symptoms were measured with the Center for Epidemiologic Studies Depression Scale (CES-D), and psychological distress was measured with the Medical Outcomes Study Short Form 36 (SF-36) mental health scale. RESULTS: Two hundred thirty-six patients were studied. Women had significantly higher median CES-D scores than men (19 versus 14, P = 0.0004), Hispanics scored higher than non-Hispanics (14 versus 8, P = 0.0002), and foreign-born scored higher than US-born patients (14 versus 10, P = 0.009). Compared with those who were fully acculturated, patients who were partially acculturated were more likely to have a score > or = 16 on the RA-adjusted CES-D (odds ratio [OR] = 1.79, 95% confidence interval [95% CI] 1.37 to 2.35, P < or = 0.001). Among unacculturated patients, the likelihood of a score > or = 16 increased 6-fold (OR = 6.68; 95% CI 3.50 to 12.72; P < or = 0.001). A similar, inverse pattern was observed for the SF-36 mental health scale. In multivariate models accounting for age, sex, education, income, articular pain, deformity, and the level of disability, low acculturation was independently associated with high depressive symptoms, and a Hispanic background was independently associated with lower SF-36 mental health. CONCLUSIONS: In this consecutive series of RA patients, Hispanics, particularly those who are not fully acculturated to the mainstream Anglo society, had more depressive symptoms and psychological distress than did non-Hispanics.

Acculturation↗
PubMed2000

Modeling impairment: using the disablement process as a framework to evaluate determinants of hip and knee flexion.

Elders often present to health care providers with multiple inter-related conditions that determine an individual's ability to function. The disablement process provides a generalized sociomedical framework for investigating the complex pathways from chronic disease to disability. At each stage of the main pathway, associations may exist among primary physical factors and modifying variables that ultimately have downstream effects on the progression toward disability. The purpose of the present analysis is to examine the inter-relationships between a cohesive set of variables primarily at the level of impairment that may affect hip and knee flexion range of motion (ROM). The San Antonio Longitudinal Study of Aging enrolled 833 community dwelling Mexican (MA) and European American (EA) elders aged 64-78 years between 1992 and 1996. Of these, 647 had complete data from both a home-based and performance-based battery of assessments for these analyses. Concerning impairments, hip ROM was measured using an inclinometer, and knee ROM using a goniometer. Pain location and intensity were assessed using the McGill Pain Questionnaire. Peripheral vascular disease was assessed using doppler brachial and ankle systolic blood pressures. Ankle and knee reflexes, and vibratory sensation were assessed by a standardized neurological examination. As to diseases, diabetes was assessed using a combination of blood glucose levels and self-report, and arthritis by self-report. Concerning modifying variables, height and weight were directly measured and used to calculate BMI. Activity level was assessed with the Minnesota Leisure Time Questionnaire. Analgesic use was assessed by direct observation of medications taken within the past two weeks. We used structural equation modeling to test associations between the variables that were specified a priori. These analyses demonstrate the central role of BMI as a determinant of hip and knee flexion ROM. For an increase in level of BMI, the coefficients [SEM] for changes in levels of hip and knee ROM were -0.38 [0.05] and -0.26 [0.05], respectively. A higher BMI resulted in lower hip and knee ROM. BMI was also directly associated with prevalent diabetes (0.10 [0.05]) and arthritis (0.17 [0.05]). However, after adjustment for BMI, diabetes and arthritis did not have direct independent associations with either hip or knee ROM. BMI was also indirectly associated with knee, but not hip, ROM through paths including lower-leg pain, pain intensity, and neurosensory impairments. Diabetes had an indirect association with hip, but not knee ROM, through a path including peripheral vascular disease. In conclusion, BMI is a primary direct determinant of hip and knee ROM. The paths by which diabetes and arthritis lead to physical disability may be mediated, in part, at the level of impairment by BMI's association with joint range of motion. Interventions designed to decrease the impact of diabetes and arthritis on disability should track changes in BMI and joint ROM to measure the paths that account for the intervention's success. The observed associations suggest that interventions targeted to decrease BMI itself may lead to improved function in part through improved joint ROM.

Aged↗
PubMed2000

Prevalence of point mutations in the dihydrofolate reductase and dihydropteroate synthetase genes of Plasmodium falciparum isolates from India and Thailand: a molecular epidemiologic study.

Pyrimethamine-sulfadoxine (PS) is used as a second-line treatment for P. falciparum malaria patients who fail to respond to chloroquine. Resistance to these drugs has been shown to encode with point mutations in dihydrofolate reductase (DHFR) and dihydropteroate synthetase (DHPS) genes. Our aim was to assess the comparative rate of point mutation occurring in DHFR and DHPS genes among P. falciparum isolates from India and Thailand where the use of PS is at a different rate. We used the mutation-specific polymerase chain reaction (PCR) technique and mutation-specific restriction digestion to determine the prevalence of DHFR and DHPS gene mutations at codons 16, 51, 59, 108, 164 and at 436, 437, 581 and 613, respectively. In the 89 clinical isolates from India, in the case of the DHFR gene, we found 71 of S108N, 10 of N51I, 28 of C59R and four of I164L types. Among the 50 isolates from Thailand the rate of point mutations in the DHFR gene was higher at four codon positions. We found 47 of S108N, 18 of N51I, 23 of C59R and 12 of I164L types. None of the isolates from either country possessed the paired mutations S108T and A16V. Mutations of the DHPS gene were less frequent among the Indian isolates: 4.5% showed DHPS gene mutation, two of S436F, A437G, A613T and two of S436F, A613T; whereas 66% (33/50) of the Thai isolates had mutated at codons 436, 437, 581 and 613 which include 13 of S436F, 15 of A437G, 19 of A581G and 25 of A613S/T, ranging from single to quadruple mutant types. Among the Indian isolates, DHFR point mutations were very frequent and 85/89 had a wild type DHPS genetic profile. The pattern of mutations in the samples from Thailand was different, as most were associated with point mutations in DHFR and DHPS genes.

Adolescent↗
PubMed2000

Overview of some biomedical research projects in tropical medicine conducted at the Instituto Venezolano de Investigaciones Cientificas.

The Instituto Venezolano de Investigaciones Cientificas (IVIC) is a government-funded multidisciplinary academic institution dedicated to research, development and technology in many areas of knowledge. Biomedical projects and publications comprise about 40% of the total at IVIC. In this article, we present an overview of some selected research and development projects conducted at IVIC which we believe contain new and important aspects related to malaria, ancylostomiasis, dengue fever, leishmaniasis and tuberculosis. Other projects considered of interest in the general area of tropical medicine are briefly described. This article was prepared as a small contribution to honor and commemorate the centenary of the Instituto Oswaldo Cruz.

Academies and Institutes↗
PubMed1999

Determinants of hip and knee flexion range: results from the San Antonio Longitudinal Study of Aging.

OBJECTIVE: We analyzed data from the San Antonio Longitudinal Study of Aging, a neighborhood-based study of community-dwelling elderly people, to identify factors that determine the flexion range (FR) of hips and knees. METHODS: The FR of hips and knees was measured in a cohort of 687 subjects aged 65 to 79 years. We used multivariate models to examine the associations among the FR of hips and knees, and between these and age, gender, ethnicity, body mass index (BMI), pain and its location, self-reported arthritis, and diabetes mellitus. The functional relevance of hip and knee FR was tested by measuring its association with 50-foot walking velocity. RESULTS: More than 90 degrees of flexion in both hips and both knees was observed in 619 subjects (90.1%). Correlations among the FR of hips and knees ranged from 0.54 to 0.80 (P < 0.001 for Spearman r values). Multivariate analysis revealed a pattern of significant associations between each of the joints and its contralateral mate and ipsilateral partner joints that was consistent for both hips and both knees. Using each individual joint as the unit of analysis, the following variables were independently associated with hip or knee FR in multivariate models: rising BMI and female sex with reduced FR of both hips and knees, a Mexican American ethnic background with decreased hip FR, and knee pain with decreased knee FR. The functional importance of the FR of these two important joints was supported by its significant association with walking velocity in a model that adjusted for age, gender, ethnic background, BMI, and hip or knee pain. CONCLUSIONS: Most community-dwelling elderly people have a FR of hips and knees that can be considered functional. The ipsilateral and contralateral hip or knee are significant independent determinants of the FR of each of these joints. Obesity, a health problem potentially amenable to preventive and therapeutic interventions, is a factor significantly associated with decreased FR of hips and knees.

Aged↗
PubMed1999

HLA-DRB1 alleles associated with susceptibility or resistance to rheumatoid arthritis, articular deformities, and disability in Mexican Americans.

OBJECTIVE: To study the genetics (HLA-DRB1 allele associations) of rheumatoid arthritis (RA) susceptibility and severity among Mexican Americans, an important, but understudied, US population. METHODS: HLA-DRB1 alleles were compared between 141 Mexican American patients with RA and 54 unrelated Mexican Americans without RA, and the association of these alleles with articular deformities and disability was examined. HLA-DRB1 alleles were typed using polymerase chain reaction-sequence-specific primer amplification and were classified according to the 1996 World Health Organization nomenclature. RESULTS: Of the 141 patients, 105 (74%) had at least 1 copy of the shared epitope (SE) sequence, compared with 29 (54%) of the 54 controls (P = 0.007). A significant gene-dose effect was observed, with 31 patients (22%) being homozygous for the SE compared with 1 (2%) of the controls (P = 0.004). In terms of disease severity, only 3% of RA patients who were "null" for the SE were outliers in the rate of development of articular deformities, compared with 10% of heterozygotes and 27% of homozygotes (P = 0.002). Patients who were DRB1*08 positive had significantly fewer deformities per year of disease and a slower rate of development of disability than did patients with other DRB1 alleles. CONCLUSION: HLA-DRB1 alleles containing the SE are associated with susceptibility to RA in Mexican Americans, and may also be associated with a more rapid development of articular deformities and disability. HLA-DRB1*08 appears to have a protective influence on RA susceptibility and disease severity in Mexican Americans.

Adult↗
PubMed1999

How much disability in rheumatoid arthritis is explained by rheumatoid arthritis?

OBJECTIVE: To measure the proportion of disability explained by disease manifestations compared with nondisease factors in rheumatoid arthritis (RA). METHODS: A hypothetical model of the disablement process specific for RA was constructed using the demographic, sociocultural, and clinical characteristics of a consecutive cohort of RA patients. Disability was measured with the modified Health Assessment Questionnaire (M-HAQ) and the physical function scale of the Medical Outcomes Study Short Form 36 (SF-36) questionnaire. Independent variables, grouped according to their position in the RA disablement process model, were sequentially entered in a series of hierarchical regression models. The proportion of variance in disability explained by each group of variables was measured by the group's incremental R2. RESULTS: The overall proportion of disability explained by the full model was 59%. Factors in the main disease-disability pathway explained 33%, of which 3% was explained by disease duration, 5% by the Westergren erythrocyte sedimentation rate, 14% by articular signs and symptoms, and 11% by performance-based functional limitations. External modifiers and contextual variables explained 26% of the variance in disability, of which age and sex accounted for 2%, formal education 4%, psychological status 17%, and symptoms of depression 3%. CONCLUSION: Both the main disease-disability pathway and factors external to this pathway contribute significantly to disability in RA. These findings provide evidence of the relative influence of psychosocial factors, compared with disease manifestations, on the disability of patients with RA.

Adult↗
PubMed1999

Cross-cultural equivalence of a brief helplessness scale for Spanish-speaking rheumatology patients in the United States.

OBJECTIVE: To show evidence of the cross-cultural equivalence between the original English version of a 5-item scale for measuring helplessness and a translated Spanish version. METHODS: English and Spanish versions of the 5 items that constitute the helplessness factor of the Rheumatology Attitudes Index were tested in 3 separate groups of patients: 1) 20 bilingual rheumatology patients; 2) 100 consecutive English- and 50 consecutive Spanish-speaking monolingual rheumatology patients; and 3) 192 English- and 44 Spanish-speaking patients with rheumatoid arthritis who were consecutively enrolled in a cohort to study disease outcomes. English-Spanish concordance among bilingual subjects was measured using intraclass correlation coefficients (ICC). Internal consistency was measured by Cronbach's coefficient alpha. Associations between the helplessness scale and variables measured simultaneously in English- and Spanish-speaking patients were measured by correlation analysis. RESULTS: Agreement between the English and Spanish versions of the helplessness scale among bilingual subjects was excellent (ICC = 0.87), and internal consistency among monolingual subjects was acceptable (coefficient alpha = 0.73 in English and 0.87 in Spanish). The correlation between helplessness and most other measured variables was of similar size and direction in English as in Spanish (10-point pain scale r = -0.53 and -0.52; modified Health Assessment Questionnaire physical disability r = -0.45 and -0.43; self-assessed joint count r = 0.36 and 0.36; Medical Outcomes Study Short Form 36 [SF-36] physical function r = 0.37 and 0.39; SF-36 mental health r = 0.27 and 0.35; Center for Epidemiological Studies Depression scale r = -0.37 and -0.33, respectively). CONCLUSION: The evidence shown supports the cross-cultural equivalence between the original 5-item helplessness scale developed in English and our translated Spanish version.

Activities of Daily Living↗
PubMed1999

Genetic diversity within Cryptosporidium parvum and related Cryptosporidium species.

To assess the genetic diversity in Cryptosporidium parvum, we have sequenced the small subunit (SSU) rRNA gene of seven Cryptosporidium spp., various isolates of C. parvum from eight hosts, and a Cryptosporidium isolate from a desert monitor. Phylogenetic analysis of the SSU rRNA sequences confirmed the multispecies nature of the genus Cryptosporidium, with at least four distinct species (C. parvum, C. baileyi, C. muris, and C. serpentis). Other species previously defined by biologic characteristics, including C. wrairi, C. meleagridis, and C. felis, and the desert monitor isolate, clustered together or within C. parvum. Extensive genetic diversities were present among C. parvum isolates from humans, calves, pigs, dogs, mice, ferrets, marsupials, and a monkey. In general, specific genotypes were associated with specific host species. A PCR-restriction fragment length polymorphism technique previously developed by us could differentiate most Cryptosporidium spp. and C. parvum genotypes, but sequence analysis of the PCR product was needed to differentiate C. wrairi and C. meleagridis from some of the C. parvum genotypes. These results indicate a need for revision in the taxonomy and assessment of the zoonotic potential of some animal C. parvum isolates.

Animals↗