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S A Almeida

Publications and source records attributed to S A Almeida.

13 recordsLinked to original sources
PubMed2002

[Epidemiological research on dementia in developing countries].

As the world population is ageing, dementia becomes an important public health problem, particularly in developing countries. Epidemiological research in these settings is scarce and present additional methodological difficulties, mainly regarding the socio-cultural adequacy of instruments used to identify cases of dementia. As a result of these concerns the 10/66 Dementia Research Group was founded to fill this gap. This is an international network of investigators, mostly from developing countries, and the group's name was based on the paradox that less than 10% of the population-based studies on dementia are directed to 2/3 or more cases of people with dementia living in developing countries. The aim of the paper is to update data in the literature regarding the differences in dementia prevalence and incidence seen in developed and developing countries.

Dementia↗
PubMed2000

Antireproductive effect of the calcium channel blocker amlodipine in male rats.

The purpose of the present study was to investigate whether treatment of male rats with the calcium antagonist amlodipine, used in the treatment of hypertension and angina, interferes with the reproductive function of male rats. Amlodipine treatment (0.04 mg amlodipine besylate/rat/day for 30 days) decreased plasma follicle-stimulating hormone and testosterone but not luteinizing hormone or prolactin concentrations (measured by double-antibody radioimmuno-assay). A significant reduction (23%) was observed in sperm density (sperm suspension collected from the cauda epididymidis) as well as in the amount of mature spermatids (14%) and Sertoli cells (9%) counted in seminiferous tubule cross-sections (400 x magnification). The results reveal the deleterious effects of subacute amlodipine treatment on the reproductive function of male rats.

Amlodipine↗
PubMed2000

Sexual behavior and fertility of male rats submitted to prolonged immobilization-induced stress.

In order to investigate whether prolonged stress interferes with the onset of sexual behavior at puberty and with fertility at adulthood, prepubertal male Wistar rats (40 days of age) were immobilized 6 h a day for 15 days (up to early puberty) or for 60 days (until sexual maturity). Pubertal stressed rats showed a two-fold increase in the latency for the first mount (probably due to repeated aversive experience in which a change of environment was always followed by immobilization) and a 2.5-fold increase in the frequency of thrusting (indicative of enhanced sexual performance). The apparently stimulatory effect of prolonged stress on the onset of sexual behavior is discussed in terms of increased testosterone level and interference with the complex interchanges between the neurotransmitters/neuropeptides involved in the central control of male sexual activity. Adult stressed animals were mated with normal females, which became pregnant but exhibited a more than two-fold increase in both pre-implantation and post-implantation loss, probably due to a smaller rate of fertilization and/or fertilization with damaged spermatozoa.

Animals↗
PubMed2000

Chronic immobilization-induced stress increases plasma testosterone and delays testicular maturation in pubertal rats.

We investigated whether chronic stress, applied from prepuberty to early puberty, interferes with the spermatogenic and androgenic testicular functions. Male pubertal rats (40 days old) were immobilized 6 h per day for 15 days. Plasma concentrations of corticosterone, prolactin and testosterone were significantly augmented following immobilization, whereas plasma luteinizing hormone decreased and follicle-stimulating hormone was not altered. Acute immobilization (5 min) increased prolactin and testosterone levels in control rats but caused a significantly higher increase in these hormones when superimposed on chronic stress. A lower extent of testicular maturation was observed in pubertal rats immobilized from prepuberty.

Animals↗
PubMed1999

Use of simple measures of physical activity to predict stress fractures in young men undergoing a rigorous physical training program.

Among a population of randomly selected US Marine Corps recruits at Marine Corps Recruit Depot, San Diego, California, the authors developed a screening tool to identify individuals at high risk for lower extremity stress fracture when beginning a rigorous physical training program. The screening tool was developed among 1,286 recruits, then tested and refined among 1,078 additional recruits. The refined algorithm, consisting of five physical activity questions and a 1.5-mi (2.4-km) run time, revealed that 21.6% of "high risk" subjects suffered more than three times as many stress fractures as "low risk" subjects. These data suggest that risk of stress fracture during rigorous physical training is increased by poor physical fitness and low levels of physical activity prior to their entry into the program.

Adolescent↗
PubMed1999

Short versions of the geriatric depression scale: a study of their validity for the diagnosis of a major depressive episode according to ICD-10 and DSM-IV.

OBJECTIVE: To determine the validity of short Geriatric Depression Scale (GDS) versions for the detection of a major depressive episode according to ICD-10 criteria for research and DSM-IV. DESIGN: Cross-sectional evaluation of depressive symptoms in a sample of elderly subjects with short GDS versions. Different GDS cutoff points were used to estimate the sensitivity, specificity, positive predictive value and negative predictive value for the diagnosis of major depressive episode. Internal consistency of the scales was estimated with the Cronbach's alpha coefficient. SETTING: Mental Health Unit for the Elderly of 'Santa Casa' Medical School in São Paulo, Brazil. PARTICIPANTS: Sixty-four consecutive outpatients aged 60 or over who met criteria for depressive disorder (current or in remission). Subjects with severe sensory impairment, aphasia or Mini-Mental State score lower than 10 were excluded from the study. MEASUREMENTS: ICD-10 Checklist of Symptoms, GDS with 15, 10, 4 and 1 items, Montgomery-Asberg Depression Rating Scale (MADRS), ICD-10 diagnostic criteria for research and DSM-IV diagnostic criteria. RESULTS: The use of the cutoff point 4/5 for the GDS-15 produced sensitivity and specificity rates of 92.7% and 65.2% respectively, and positive and negative predictive values of 82.6% and 83.3% respectively when ICD-10 diagnostic criteria for major depressive episode were used as the 'gold standard'. Similarly, rates of 97.0%, 54.8%, 69.6% and 94.4% were found when DSM-IV was the comparing diagnostic criteria. Sensitivity, specificity and positive and negative predictive values for the cutoff point 6/7 were 80.5%, 78. 3%, 86.8% and 69.2% according to ICD-10, and 84.8%, 67.7%, 73.7% and 80.8% respectively according to DSM-IV. Intermediate values were found for the cutoff point 5/6. The best fit for GDS-10 was the cutoff point 4/5, which produced a sensitivity rate of 80.5%, specificity of 78.3%, positive predictive value of 86.8% and negative predictive value of 60.2% according to ICD-10 diagnosis of a major depressive episode. Similarly, rates of 84.8%, 67.7%, 73.7% and 80.8% were found when DSM-IV criteria for major depression were used. GDS-4 cutoff point of 2/3 was associated with a sensitivity rate of 80.5%, specificity of 78.3%, positive predictive value of 86. 8% and negative predictive value of 69.2% when compared to ICD-10. Again, rates of 84.8%, 67.7%, 73.7% and 80.8% respectively were found when the criteria used were based on DSM-IV. GDS-1 had low sensitivity (61.0% and 63.6% for ICD-10 and DSM-IV respectively) and negative predictive value (56.7% and 67.6% for ICD-10 and DSM-IV respectively), suggesting that this question is of limited clinical utility in screening for depression. GDS-15 (rho=0.82), GDS-10 (rho=0.82) and GDS-4 (rho=0.81) scores were highly correlated with subjects' scores on the MADRS. Reliability coefficients were 0.81 for GDS-15, 0.75 for GDS-10 and 0.41 for GDS-4. CONCLUSION: GDS-15, GDS-10 and GDS-4 are good screening instruments for major depression as defined by both the ICD-10 and DSM-IV. The shorter four- and one-item versions are of limited clinical value due to low reliability and failure to monitor the severity of the depressive episode. General practitioners may benefit from the systematic use of short GDS versions to increase detection rates of depression among the elderly. (c) 1999 John Wiley & Sons, Ltd.

Aged↗
PubMed1999

Epidemiological patterns of musculoskeletal injuries and physical training.

PURPOSE: The purpose of this study was to identify rates of diagnosis-specific musculoskeletal injuries in U.S. Marine Corps recruits and to examine the association between patterns of physical training and these injuries. METHODS: Subjects were 1,296 randomly selected male Marine recruits, ages 17 to 28 yr, who reported to Marine Corps Recruit Depot San Diego for boot camp training between January 12 and September 14, 1993. Recruits were followed prospectively through 12 wk of training for injury outcomes. Injury patterns were examined in relation to weekly volumes and types of vigorous physical training. RESULTS: The overall injury rate was 39.6% (number of recruits injured/population at risk), with 82% of injuries occurring in the lower extremities. Overuse injuries accounted for 78% of the diagnoses. The most frequent site of injury was the ankle/foot region (34.3% of injuries), followed by the knee (28.1%). Ankle sprains (6.2%, N = 1,143), iliotibial band syndrome (5.3%, N = 1,143), and stress fractures (4.0%, N = 1,296) were the most common diagnoses. Injury rates were highest during the weeks with high total volumes of vigorous physical training and the most hours of running and marching. Weekly injury rates were significantly correlated with hours of vigorous physical training (overuse injuries r = 0.667, P = 0.018; acute injuries r = 0.633, P = 0.027). CONCLUSIONS: The results of this controlled epidemiological investigation indicate that volume of vigorous physical training may be an etiologic factor for exercise-related injuries. The findings also suggest that type of training, particularly running, and abrupt increases in training volume may further contribute to injury risk.

Adolescent↗
PubMed1999

Gender differences in musculoskeletal injury rates: a function of symptom reporting?

PURPOSE: This study determined gender differences in voluntary reporting of lower extremity musculoskeletal injuries among U.S, Marine Corps (USMC) recruits, and it examined the association between these differences and the higher injury rates typically found among women trainees. METHODS: Subjects were 176 male and 241 female enlisted USMC recruits who were followed prospectively through 11 wk (men) and 12 wk (women) of boot camp training. Reported injuries were measured by medical record reviews. Unreported injuries were determined by a questionnaire and a medical examination administered at the completion of training. RESULTS: Among female recruits the most commonly reported injuries were patellofemoral syndrome (10.0% of subjects), ankle sprain (9.1%), and iliotibial band syndrome (5.8%); the most common unreported injuries were patellofemoral syndrome (2.1%), metatarsalgia (1.7%), and unspecified knee pain (1.7%). Among male recruits iliotibial band syndrome (4.0% of subjects), ankle sprain (2.8%), and Achilles tendinitis/bursitis (2.8%) were the most frequently reported injuries; shin splints (4.6%), iliotibial band syndrome (4.0%), and ankle sprain (2.8%) were the most common unreported diagnoses. Female recruits were more likely to have a reported injury than male recruits (44.0% vs 25.6%, relative risk (RR) = 1.72, 95% confidence interval (CI) 1.29-2.30), but they were less likely to have an unreported injury (11.6% vs 23.9%, RR = 0.49, 95% CI 0.31-0.75). When both reported and unreported injuries were measured, total injury rates were high for both sexes (53.5% women, 45.5% men, RR = 1.18, 95% CI 0.96-1.44), but the difference between the rates was not statistically significant. CONCLUSIONS: Our results indicate that the higher injury rates often found in female military trainees may be explained by gender differences in symptom reporting.

Adolescent↗
PubMed1999

[Reliability of the Brazilian version of the ++abbreviated form of Geriatric Depression Scale (GDS) short form].

Depression is a frequent health problem in old age, although the detection of such cases in clinical practice is often difficult. The systematic use of depression rating scales may increase diagnostic rates of depression amongst the elderly. This study aimed to assess the test-retest reliability of short versions of the Geriatric Depression Scale (GDS) with 1, 4, 10, and 15 items. Sixty-four consecutive patients aged 60 or over attending the outpatient clinic for the elderly (UNID) at the Department of Mental Health of Santa Casa of São Paulo were recruited for the study between February and May 1998. All subjects fulfilled criteria for the diagnosis of a depressive disorder (current or in remission) according to ICD-10, and had Mini Mental State scores greater than 10. They were evaluated twice in 48 to 72 hours with the GDS-15. Fifty-one patients completed both assessments. Agreement between scores for individual items was evaluated with Kappa statistic. Kappa coefficients ranged from 0.04 to 0.49, indicating that there was much variation within individual items. Total GDS-15 scores were reasonably stable, as assessed by paired Wilcoxon (z = 1.60, p = 0.109), Spearman correlation coefficient (rho = 0.86, p < 0.001), and weighted Kappa (Kappa = 0.64). The same pattern was also observed for the total scores of the GDS-10 on the paired Wilcoxon (z = 0.85, p = 0.402), Spearman correlation coefficient (rho = 0.81, p < 0.001), and weighted Kappa (Kappa = 0.60). Total score for the GDS-4 showed significant changes from test to retest (z = 3.75, p < 0.001; rho = 0.56, p < 0.001; Kappa = 0.37). These results indicate that the short GDS versions with 1 and 4 items are unreliable for use in clinical practice. In contrast, the GDS with 10 and 15 items produced consistent results in the assessment of elderly patients when total scores were used as clinical guidelines.

Aged↗
PubMed1998

Chronic intermittent immobilization of male rats throughout sexual development: a stress protocol.

A stress protocol--6 h of daily immobilization--was applied throughout male rat sexual development. Immobilization caused a small reduction in food intake and body weight gain whereas pair-fed animals had a marginal decrease only in body weight gain. Stress, confirmed by increased plasma adrenocorticotrophic hormone (ACTH) and corticosterone, caused a decrease in plasma luteinizing hormone (LH) after 15 and 60 days of immobilization and in plasma testosterone after 60 days, but produced an opposite androgenic response in pubertal animals (15 days of immobilization). A persumed sympathetic over-stimulation is suggested to account for increased testosterone levels in pubertal stressed rats.

Adrenocorticotropic Hormone↗
PubMed1998

Decreased spermatogenic and androgenic testicular functions in adult rats submitted to immobilization-induced stress from prepuberty.

We investigated whether chronic stress applied from prepuberty to full sexual maturity interferes with spermatogenic and androgenic testicular functions. Male Wistar rats (40 days old) were immobilized 6 h a day for 60 days. Following immobilization, plasma concentrations of corticosterone and prolactin increased 135% and 48%, respectively, while plasma luteinizing hormone and testosterone presented a significant decrease of 29% and 37%, respectively. Plasma concentration of follicle-stimulating hormone was not altered in stressed rats. Chronic stress reduced the amount of mature spermatids in the testis by 16% and the spermatozoon concentration in the cauda epididymidis by 32%. A 17% reduction in weight and a 42% decrease in DNA content were observed in the seminal vesicle of immobilized rats but not in its fructose content. The growth and secretory activity of the ventral prostate were not altered by chronic stress.

Androgens↗
PubMed1996

Sexual development of hypernatriophilic male rats up to puberty.

The sexual development of normonatriophilic (Normo) and hypernatriophilic (Hyper) male Wistar rats was compared from 30 to 60 days of age (N = 8-10 per group) with emphasis on the onset of puberty. Hyper rats (more than 5 ml of saline a day in a situation of free access to tap water and 1.5% NaCl) had a 20-39% body weight reduction and a 22-29% testicular growth rate decrease compared to Normo rats. Plasma testosterone (ng/ml) of Normo rats increased from 0.29 +/- 0.02 at 30 days to 1.42 +/- 0.18 at 50 days, decreasing to 0.87 +/- 0.15 at 60 days of age, with no significant difference compared to Hyper animals. Plasma concentration (ng/ml) of luteinizing hormone (LH) was significantly lower in Hyper (0.21 +/- 0.03) than in Normo (0.43 +/- 0.06) rats at 40 days. At 30 days, plasma follicle stimulating hormone (FSH) levels (ng/ml) were significantly higher in Hyper (18.9 +/- 1.3) than in Normo (15.6 +/- 0.5) rats. It is possible that increased levels of FSH compensated for a reduced amount of LH, thus allowing similar testosterone production by Hyper and Normo rats. At 30 days, testis maturation was higher in Hyper rats, as indicated by a 22% increase in tubular cross-sections with young spermatids. At 50 days, spermatogenesis progressed to the production of mature spermatids (onset of puberty) and Hyper rats exhibited an 18.7% lower rate of testis maturation. Testis maturation was similar in Hyper and Normo rats at 60 days.

Animals↗