Biomedical subjects

I S Santos

Publications and source records attributed to I S Santos.

9 recordsLinked to original sources

PubMed2000

Nicotinic modulation in an animal model of a form of associative learning impaired in Alzheimer's disease.

Eyeblink classical conditioning is a widely used associative learning paradigm that has striking behavioral and neurobiological parallels between humans and other mammals. Eyeblink conditioning is impaired in older organisms, and patients with Alzheimer's disease (AD) are impaired beyond the normal aging deficit. The cholinergic system is of demonstrated involvement in eyeblink conditioning. Blockade of nicotinic cholinergic receptors with mecamylamine prolonged acquisition of conditioned responses (CRs) in young adult rabbits, and the nicotinic agonist, GTS-21 ameliorated conditioning deficits in older rabbits. Galantamine induces allosteric modulation of nicotinic cholinergic receptors to increase acetylcholine release as well as acting as an acetylcholinesterase inhibitor. Galantamine doses of 0.0, 1.0, 2.0, 3.0, and 4.0 mg/kg were tested in ten daily sessions in 40 retired breeder rabbits (mean age = 29 months) in the 750 ms delay conditioning paradigm. A dose of 3 mg/kg galantamine was effective in improving conditioning in older rabbits, enabling them to achieve learning criterion rapidly and to produce a very high percentage of CRs. Control tests of rabbits in explicitly unpaired conditions demonstrated that non-associative factors could not account for the results. The efficacy of galantamine in a learning paradigm that shows severe impairment in AD indicates that the drug may be effective as a cognition-enhancer in AD.

Age Factors↗

PubMed2000

[Criteria for choosing health care facilities for prenatal care in Pelotas, RS, Brazil].

OBJECTIVE: To describe the prenatal care delivered to a representative sample of mothers, identifying the health care facility they attended and to explore the reasons that led them to choose that specific health facility. METHOD: A cross-sectional study was conducted at four maternity hospitals in Pelotas, in Southern Brazil, from March to April 1997. A total of 401 mothers were interviewed at the hospital, immediately after delivery. RESULTS: The majority of mothers (51%) were followed up at a primary health care facility (PHCF). The main reported reason for choosing a PHCF was its geographic accessibility (46.8%). For 85% of the mothers, the nearest health service was a PHCF. However, 52.2% of them did not attend the consultations at this setting mainly because of a supposed low quality care (37.4%). Except for immunization with tetanus toxoids, all other usual prenatal care procedures recommended by the local health ministry, including promotion of breastfeeding, were performed less frequently at the PHCF than in other health care settings. CONCLUSION: Given the high coverage of the public prenatal care program, efforts should be made to improve the quality of care delivered to pregnant women, mainly by encouraging health professionals, especially doctors, to follow the established guidelines.

Adolescent↗

PubMed1999

Impact of breast feeding on admission for pneumonia during postneonatal period in Brazil: nested case-control study.

OBJECTIVE: To determine whether breast feeding protects infants against pneumonia and whether the protection varies with age. DESIGN: Nested case-control study. SETTING: Pelotas, southern Brazil. SUBJECTS: Cases were 152 infants aged 28-364 days who had been admitted to hospital for pneumonia. Controls were 2391 cases in a population based case-control study. MAIN OUTCOME MEASURE: Odds ratio of admission for pneumonia according to type of milk consumed (breast milk alone, breast and formula milk, or formula milk and other fluids only), use of fluid supplements apart from formula milk, and use of solid supplements. RESULTS: Infants who were not being breast fed were 17 times more likely than those being breast fed without formula milk to be admitted to hospital for pneumonia (95% confidence interval 7.7 to 36.0). This relative risk was 61 (19.0 to 195.5) for children under 3 months old, decreasing to 10 (2.8 to 36. 2) thereafter. Supplementation with solids was associated with a relative risk of 13.4 (7.6 to 23.5) for all infants and 175 (21.8 to 1405.1) for those under 3 months old. CONCLUSION: Breast feeding protects young children against pneumonia, especially in the first months of life. These results may be used for targeting intervention campaigns at the most vulnerable age groups.

Brazil↗

PubMed1998

Caffeine intake and low birth weight: a population-based case-control study.

The authors conducted a matched case-control study to investigate the effects of caffeine intake during pregnancy on birth weight. From January to November 1992, in the first 24 hours after delivery, 1,205 mothers (401 cases and 804 controls) were interviewed and their newborns were examined to assess birth weight and gestational age by means of the method of Capurro et al. (J Pediatr 1978;93:120-2). The cases were children with birth weight < 2,500 g and gestational age > or = 28 weeks. Cases and controls were matched for time of birth and hospital of delivery and were recruited from the four maternity hospitals in Pelotas, southern Brazil. Daily maternal caffeine intake during pregnancy for each trimester was estimated. To assess caffeine intake, 10% of the mothers were reinterviewed at their households and samples of reported information on drip coffee and maté (a caffeine-containing drink widely used in South America) were collected and sent to the laboratory for caffeine determination through liquid chromatography. When instant coffee was reported, the weight of powder was measured using a portable scale, and caffeine intake was estimated from a reference table. Caffeine intake from tea, chocolate, soft drinks, and medicines was estimated from a reference table. Analyses were performed by conditional logistic regression. Crude analyses showed no effect of caffeine on low birth weight, preterm births or intrauterine growth retardation. The results did not change after allowing for confounders.

Beverages↗

PubMed1997

[Hospitalization due to pneumonia: the influence of socioeconomic and pregnancy factors in a cohort of children in Southern Brazil].

OBJECTIVE: To investigate the influence of socioeconomic and gestational factors on admission due to pneumonia in the post-neonatal period. METHODOLOGY: Cohort. Children born in the city Pelotas, Brazil, in 1993. Cases were children admitted to hospital for 24 hours or more, between the ages of 28 and 364 days, with a diagnosis of pneumonia. RESULTS: Of the 5,304 children in the cohort, 152 (2.9%) were hospitalized with pneumonia. The positive predictive value of the clinical diagnosis compared to the radiological assessment was 76%. Analysis by conditional logistic regression showed that social class and maternal schooling were strongly inversely associated with pneumonia Children of adolescent mothers were twice as likely to be admitted. The relative risk for children whose mothers were of parity three or greater was 2.8 relative to primiparae. Maternal weight gain during pregnancy of less than 10 kg was associated with a 40% increase in risk. CONCLUSION: Socioeconomic factors were important determinants of pneumonia admissions. Maternal age, parity and weight gain were also significant risk factors.

Brazil↗

PubMedDate not supplied

Caffeine intake and pregnancy outcomes: a meta-analytic review.

Epidemiological publications on the relationship of caffeine to birth weight and duration of human pregnancy, from 1966 to 1995, were searched through Medline. Each study was treated as the stratification variable, and its weight average was proportional to the inverse of its variance. Twenty-six studies were located. Among the twenty-two studies on birth weight, eleven were on mean birth weight, nine on low birth weight (LBW), and four on intrauterine growth retardation (IUGR). Combined analysis of mean birth weight study results showed a significant decrease in birth weight of nearly 43g among newborns of the heaviest caffeine-consuming mothers. LBW, IUGR, and preterm delivery displayed significant homogeneity in the test results, indicating that a pooled estimate should not be taken as na adequate measure. The high heterogeneity of the available literature on the effects of caffeine on LBW, IUGR, and preterm delivery prevents estimation of reliable pooled estimates through meta-analysis. Further assessment of caffeine intake during pregnancy is needed in future research.

Birth Weight↗

PubMedDate not supplied

[Adults without caries: a case-control study about knowledge, attitudes and preventive practices].

The purpose of this article was to investigate the effect of personal awareness and attitudes, the dentist's role, oral hygiene habits, and fluoride use on total absence of caries in adults, using a case-control study, matched for sex and age with undergraduate students from two private Brazilian universities. Crude analysis using conditional logistic regression failed to show any effect for the related variables regarding fluoride use and oral hygiene habits (p > 0.20). Use of dental floss was the only exception in this set. It appeared as a risk factor, since individuals who stated not flossing presented a crude odds ratio (OR) of 0.70, or 0.73 when adjusted for regular visits to the dentist. The effect for regular visits to the dentist was that of a risk. Those with a history of caries presented a crude odds ratio of 1.55; after adjusting for dental floss use, the risk was slightly higher (OR = 1.67). Oral hygiene habits, contrary to the formulated hypothesis, did not display the expected protective effect. Likewise, fluoride use was not significantly associated with absence of caries. Individuals with a history of caries were used to visiting more professionals, confirming the formulated hypothesis for this variable. Nevertheless, it is still intriguing that some people fail to develop caries, even they report not practicing measures considered ideal for oral health.

Adult↗

PubMedDate not supplied

[Prenatal care at the primary health care level: an assessment of the structure and process].

With the aim of describing the structure and process by which prenatal care is provided at the primary health care level in the city of Pelotas in southern Brazil, a descriptive cross-sectional study was conducted. All 31 urban health care facilities were visited and their structure analyzed. A total of 839 prenatal records from mothers who delivered in the six months prior to the beginning of the study were reviewed. The structure as a whole was classified as poor (only 70% of standard parameters were present), mainly due to deficiencies in the physical plant. Process assessment showed low coverage (53%) and an average of 5.3 visits. Only 37% of patient records showed adequate results (Kessner Index). Adding laboratory test results and routine procedures as complementary criteria, 31% and 5% of the records scored as adequate, respectively. In summary, overall quality of prenatal care provided at the primary health care level in Pelotas is poor. Mechanisms to increase staff adherence to both procedures and program logistics need to be developed.

Adolescent↗

PubMedDate not supplied

[Epidemiology of polydactylies: a case-control study in the population of Pelotas-RS]

OBJECTIVE: To identify and compare cases of isolated polydactyly with healthy newborns regarding familial and maternal characteristics. METHODS: We conducted this hospital-based case-control study from 1990 to 1998. We collected data in interviews with mothers of cases and controls during the post-delivery period. Cases were defined as newborns presenting an extra or a bifid digit in hands and/or feet. Controls were the four healthy newborns that were born after the case, at the same hospital. Information was gathered on type of polydactyly, gender and birthweight, twin pregnancy, parental consanguinity, ethnicity. RESULTS: African ancestry and positive family history of congenital malformation, especially polydactyly, were significantly associated with the occurrence of this type of congenital anomaly (crude OR of 3.3; 10.0; and 55.0, respectively). CONCLUSION: Isolated polydactyly was one of the most frequent malformations found in the studied population. The findings associated with black African ancestry confirm the data presented in the literature. Studies conducted on this same population, with a larger population of patients with this type of malformation, could investigate this association better and justify the results presented here.

Journal Article↗