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Biomedical subjects

M C Costa

Publications and source records attributed to M C Costa.

At least 55 records · Page 3Linked to original sources
PubMed1987

The osmosedimentation effect: its application to chemical and biochemical separation.

1. The fundamentals of the osmosedimentation effect are reviewed and its applications to chemical and biochemical separation problems are presented. 2. The osmosedimentation effect (solute sedimentation enhanced by osmotic and reverse-osmotic solvent mass currents spontaneously generated within a vertical dialysis cell) may be described by using standard treatments of non-equilibrium thermodynamics. 3. This effect allows many hitherto unfeasible or very difficult experiments to be performed: polymer and particle MW determination, under gravity or low-speed (1000-5000 rpm) centrifugation; dissolved protein concentration, by low-speed centrifugation; density gradient generation, at low centrifugation speeds; fast separation of fine particles; particle concentration and fractionation, under gravity and low speed centrifugation. 4. Osmocentrifugation methods may be easily implemented in any laboratory, as their requirements are: the availability of standard centrifuges and rotors, inexpensive dialysis cells and cellulose acetate membranes, which can be prepared in the laboratory.

Centrifugation, Density Gradient↗
PubMed1986

Confronting cisternae in human hepatocellular carcinoma.

The Authors report the presence of confronting cisternae (CC) in two cases of poorly differentiated human hepatocellular carcinoma. They are interpreted as a peculiar phenotypical alteration of the tumor cells, probably related to a disturbance of the morphogenesis of nuclear and endoplasmic membranes.

Aged↗
PubMedDate not supplied

An exanthematic disease epidemic associated with coxsackievirus B3 infection in a day care center.

An epidemic of exanthematic illness in a day care center is described. Ten children aged 7 to 13 months were affected by the illness. The exanthem was characterized by nonconfluent macular or maculopapular lesions that appeared on the face, body and limbs. Fifty percent of the infected children had fever of up to 39 degrees C at the beginning of the disease. Coxsackievirus B3 (CB3) was isolated from the stool of one ill child. Paired serum samples were obtained from eight ill children and six of them presented seroconversion to CB3. Antibodies to CB3 were detected at titers higher than 16 in a single serum sample collected from the other two patients. Neutralizing antibodies to CB3 were detected in 71.0% of the contact children.

Antibodies, Viral↗
PubMedDate not supplied

[Epidemiology of dengue in Salvador-Bahia, 1995-1999].

Since 1981, Brazil has registered dengue epidemic and simultaneous circulation of the DEN-1 and DEN-2 serotypes in over 2,700 municipalities. In Salvador- Bahia, located in the Northeastern region of the Country, two epidemic outbreaks occurred in the years of 1995 and 1996, with further endemic spread of the disease. This study analyses the incidence of the virosis within this municipal area, from 1995 to 1999, considering, among other variables, its distribution in the Sanitary Districts and density of Aedes aegypti. Registers of notified cases and the city's Vectorial Control Program were used as data source. The incidence rate of notified cases of dengue in 1995 and 1996, which were 691.4 and 393.5 per 100,000 inhabitants, respectively, decreased to 65 per 100,000 inhabitants in 1998. In the poorer Sanitary Districts, this index reached figures of over 800 per 100,000 inhabitants. The Premise Index for Aedes aegypti reached 54.1% in one of the Districts. Bearing in mind the relevance of the re-emergence of dengue in the world, the authors discuss the possible factors which condition the virus introduction, its epidemiological presentation over the course of four years, and the effectiveness of the vectorial combat (eradication) program.

Adolescent↗
PubMedDate not supplied

Intratypic differentiation of polioviruses isolated from suspected cases of poliomyelitis in Brazil during the period of 1990 to 1993.

This study analyzed 3129 fecal samples derived from 1626 patients with sudden onset acute flaccid paralysis clinically compatible with poliomyelitis. The samples were collected in the period ranging from January 1990 to September 1993 in all regions of Brazil. Among the 1626 cases studied, 196 had isolation of poliovirus. Nevertheless, it was observed that some factors influenced the isolation rate and the intratypic characterization of these polioviruses. No cases of acute flaccid paralysis has been found to be etiologically related with wild polioviruses.

Acute Disease↗
PubMedDate not supplied

[Evaluation of a comprehensive adolescent health care service].

The authors evaluate the Adolescent Health Clinic in the Emaús community in Belém, Pará, Brazil with regard to coverage, adequacy, accessibility, and utilization for the period 1994 to 1996. Coverage was calculated on the basis of clinical records and information collected from the target population. Adequacy was analyzed by comparing the service performance with goals established by PAHO/WHO for this kind of institution. Accessibility and utilization patterns were evaluated from information obtained by a population-based survey among adolescents living in the area. Results showed: a good degree of program adequacy vis-à-vis the final purpose, although some adjustments are needed, especially in human resources; lack of barriers to user access; reasonable coverage, despite the low proportion of consultations by adolescents; and utilization pattern compatible with the service provision profile, mainly directed towards curative and individual care. Recommendations are made to revise the hegemonic health care model to emphasize preventive, collective, and educational activities.

Adolescent↗
PubMedDate not supplied

[Infant mortality and living conditions: the reproduction of social inequalities in health during the 1990s].

An ecological study was conducted to determine the infant mortality trend from 1991 to 1997 and to analyze its relationship to living conditions in Salvador, Bahia State, Brazil. Inequality patterns in infant death were analyzed by spatial distribution and a compound socioeconomic index. The data showed a decline in the infant mortality rate, with neonatal deaths and perinatal causes playing a growing role. Despite this overall trend, the infant mortality rate increased in 1992, and it was only in 1997 that it returned to the 1991 level. This fact was interpreted as related to worsening living conditions during that period. Spatial distribution highlights the persistence of health inequalities; education was the variable with the most significant correlation rate. When distributed according to the living conditions index (LCI), both the infant mortality rate and proportional infant mortality showed a linear increase from the intermediate stratum (20.4 per mil ) to the lowest (29.3 per mil ) and from the highest stratum (5.3%) to the lowest (13.3%), respectively. The authors conclude that despite the reduction in the total infant mortality rate, the persistence of social inequalities and a social process that hinders improvement of living conditions are responsible for the inequalities observed in infant mortality.

Brazil↗
PubMedDate not supplied

[Topical fluoride in the reduction of dental caries in adolescents in Salvador, BA, 1996].

The aim of this paper was to investigate the experience of dental caries in a population of young adults from Salvador--BA, and to associate the prevalence of caries with the utilization of topical fluoride. A cross-sectional study was carried out with a sample of 493 persons aged 12-20 years, from Salvador--BA. Data were obtained from interviews and clinical examinations and they were analyzed through backward logistic regression. The DMFT was 4.44 (SD 3.71), and, for subjects aging 12-13 years, it was 2.72 (SD 2.75). A hundred and forty adolescents reported that they had participated in oral health programs (30%), and the majority felt that they were unable to maintain their own oral health. Topical fluoride was not a significant factor in the decrease of the prevalence of caries among these young adults (RP = 0.9). There was a decline in dental caries in this group. However, it is necessary to review the surgical-restorative model of dental practice in order to achieve better results in the promotion of oral health.

Adolescent↗
PubMedDate not supplied

[Mother-infant indicators in adolescence and youth: socio-demographic, prenatal, delivery and newborns]

OBJECTIVE: To identify characteristics and associations between maternal age and gestation, delivery, and livebirths of adolescent and young adult mothers in the city of Feira de Santana, state of Bahia, Brazil. METHODS: We carried out a cross-sectional, epidemiological study with a population of livebirths and adolescent mothers (aged 10-16 and 17-19 years) and young adult mothers (aged 20-24 years). The information were obtained from the Livebirths Information System (SINASC-1998) for a total of 5,279 livebirths. Study variables were classified into socio-demographic factors (age, schooling of the mother, sex of the newborn) and related to term, delivery, gestational age, birth weight, and Apgar score. Data were processed using prevalence ratio and multivariate analysis. Logistic regression was used to control confounding factors (prenatal and gestational age) and to establish an association between maternal age and birth weight. RESULTS: In 1998, 21.6% of all livebirths in the city of Feira de Santana were from adolescent mothers; out of these mothers, 51.2% had not finished junior high or elementary school. Prevalence ratio and adjusted odds ratio for the 10-16 years of age group indicated increased prevalence of illiteracy, no prenatal examination, and low birth weight and a low prevalence of adequate weight of the newborn in comparison to other age groups studied. Logistic regression showed a positive association between maternal age and low birth weight. We also observed that the SINASC database lacked information in many different fields. CONCLUSIONS: Our results indicated, for adolescent mothers, a high prevalence of livebirths and low schooling. Also, especially for the 10-16 years of age group, we observed increased risks for illiteracy, no prenatal examinations, low birth weight, and inadequate weight of the newborn in comparison to other age groups.

Journal Article↗
PubMedDate not supplied

[Nutritional approach in pregnant and nursing adolescents: basic strategy to prevent risks]

OBJECTIVE: To present the different factors that can interfere in the neonatal evolution and results, as well as the approach strategic nutritional aspects in health promotion and attention of pregnant nursing adolescents. METHOD: National and international literature provided with subsidies to discuss and summarize practical and relevant aspects for the clinical assistance of pregnant and nursing adolescents, especially the lower age group. RESULTS: The approach to pregnant adolescents requires evaluation of parameters of clinical, nutritional, and psychosocial risk. Among the very young adolescents, in addition to those parameters, their gynecological age and physical growth stage are also relevant. The nutritional evaluation and the dietary orientation of the pregnant and nursing adolescents constitute support steps in health promotion and attention, preventing risks such as malnutrition, anemia, vitamin deficiency, in addition to low intrauterine growth, low birth weight and postnatal undernourishment. CONCLUSION: The complexity of the factors interfering in the course of precocious pregnancy requires deep knowledge of the problem by the health staff in order to be able to effectively to intervene in more critical and prior aspects of the health support for this risk group.

Journal Article↗
PubMedDate not supplied

[Challenges in the approach to adolescents: confidentiality and contraceptive orientation]

OBJECTIVE: The article has the purpose of presenting some questions related to professional ethics and juridical aspects of the approach to sexuality in adolescence, as well as of offering a practical review of the approach and contraceptive methods used by adolescents.METHODS: The bibliographic review encloses national and international literature, as well as juridical orientation in specific questions related to Child and Adolescent Statute and Brazilian Penal Code.RESULTS: Among the aspects of the approach to adolescents, confidentiality is distinguished as one of the most important strategies, mainly when the topic is associated to questions related to sexuality. In Brazil, although adolescents have been contributing in an effective way to the increase in the fecundity rate, there is, legally speaking, a hiatus concerning the guarantee of the rights of adolescents and professionals in exercise of contraceptive practice.CONCLUSIONS: The challenge for the health professionals, particularly the pediatricians who deal with adolescents, is to collaborate on the consolidation of rules which regulate the orientation in reproductive health for adolescents, once Brazilian Penal Code is anachronous concerning the reality of sexual behavior and its possible consequences.

Journal Article↗
PubMedDate not supplied

[Psychosocial and sexual aspects of pregnant adolescents at Belém-Pará].

Pregnancy is a major factor that modifies psychosocial aspects of the adolescents. A study with 120 pregnant adolescents aged 12 to 18 years, without regarding gestational age, was carried out at Prenatal Risk Program in the Secretaria Estadual de Saúde, Belém-Pará, from 10/1991 to 04/1992. At the first encounter, it was made an approach of psychosocial and sexual subjects, with the following results: onset of menarche primarily between 12-13 years old (median 12.2 years old); beginning of sexual practice at 14 years old in 50.9% of the adolescents. 56.6% were pregnant at 16 years old. Most of the adolescents (98.4%) first had sexual intercourse with their boy friends and by their own wish (72.5%). In one year of loving affair, 67.5% of the adolescents have already begun sexual activities, this attitude more prevalent among the younger(79.4%). Adolescents had learned about sexuality mainly from mates (65.1%). Although 55.9% of the adolescents were aware of some contraceptive method, just 13.3% of them used one. The majority of the pregnant adolescents (96.7%) were financially supported by their families. Respectively, 30.3% and 32.1% of these girls left school before or during pregnancy. The risk factors that may contribute to an early and unintended pregnancy among adolescents, specially the younger ones, were pointed out: little information about sex and contraceptive methods, limited practice on their use and a high rate of precocious sexual activities.

English Abstract↗
PubMedDate not supplied

[Decline and social inequalities of infant mortality caused by diarrhea].

This ecological study describes the temporal trend from 1977 to 1998, and spatial patterns of infant mortality from diarrhea in the city of Salvador, Bahia State, Brazil. The annual proportional of infant mortality and specific-cause mortality rate were estimated. Spatial units of geographical zones within the city's urban area were utilized for administrative purposes, which were aggregated according to quartile of living conditions indicators. Over the study period, the diarrhea-induced infant mortality rate decreased 91.9%. The mortality risk from diarrhea in the lowest living condition strata was 90% greater than in the highest conditions. Also, infant mortality due to diarrhea increases proportionally as living conditions worsen, which necessitates a review of the control policies concerning this important public health problem. Although the infant mortality rate declined during the study period, social inequalities related to infant mortality due to diarrhea persist, reflecting a continuing poor social development.

Brazil↗