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C Barroso

Publications and source records attributed to C Barroso.

29 records · Page 2Linked to original sources

The meiotic chromosomes of Cebus apella (Cebidae, Platyrrhini).

An analysis of the meiotic chromosomes of Cebus apella (Cebidae, Platyrrhini) has allowed for the visualization of constitutive heterochromatic regions throughout the meiotic cycle and has permitted the identification of four chromosomes in the first and the second divisions. In pachytene nuclei, and in pachytene spreads where synaptonemal complexes were visible, one heterochromatic region was frequently unpaired. No chiasmata were found in heterochromatic regions, and there was no evidence of chiasma terminalization. The role of heterochromatin in homologous pairing and its relationship to chiasma position and number in meiotic configurations were discussed. A comparison was made between bivalent 9 in C. apella and bivalent 21 in man, based on the interspecific homologies between these chromosomes. A similar comparison was made between the Algerian and Asian hedgehogs, where marked differences in the content of constitutive heterochromatin occur in two chromosome pairs.

Animals↗

Silver nitrate: antimicrobial activity related to cytotoxicity in cultured human fibroblasts.

The aims of this study were to ascertain whether silver nitrate (AgNO3) concentrations below those used in clinical practice inhibit bacterial growth, and in parallel study the cytotoxic effects on human fibroblasts. The cytoprotective effects of fetal calf serum (FCS) were also evaluated. The cytotoxic effects of eight different silver nitrate concentrations were determined by assessing mitochondrial activity of viable cells capable of cleaving tetrazolium salts. Antimicrobial activity of AgNO3, range: 7-550 x 10(-5)%, was tested against Staphylococcus aureus, Citrobacter freundii, and Pseudomonas aeruginosa. Silver nitrate concentrations exerting antimicrobial effects were: S. aureus, >70 x 10(-5)%; P. aeruginosa, >/=270 x 10(-5)%, and C. freundii, >/=550 x 10(-5)%. With 2% FCS, the lowest AgNO3 concentration studied (7 x 10(-5)%) showed cytotoxic effects (cell survival 71 +/- 19%) at only 2 h of incubation. Under these conditions AgNO3 cytotoxicity was time- and concentration-dependent in all exposure periods. Cytotoxicity was greatly enhanced causing 76% fibroblast growth inhibition at concentrations of 14 x 10(-5)% and contact time of 2 h. The AgNO3 concentration of 7 x 10(-5)% was also cytotoxic with 5% FCS in the media compared with controls, although cell survival was higher than with 2% FCS. The cytoprotective action of FCS was clearly shown at the concentration of 10% at which AgNO3 cytotoxicity of 7 x 10(-5)% to 28 x 10(-5)% was partially or completely inhibited. Our results show that AgNO3 at concentrations 100-700 times more diluted than that normally used in clinical practice retained effective inhibitory activity against some of the above-mentioned microorganisms. However, even these concentrations are cytotoxic for cultured fibroblasts. Thus, silver nitrate concentrations up to 100 times more diluted can be used, since they possess bacterial growth-inhibiting power, are less cytotoxic and therefore favour wound healing.

Anti-Infective Agents, Local↗

Hispanic women's breast and cervical cancer knowledge, attitudes, and screening behaviors.

PURPOSE: This study examined breast and cervical cancer knowledge, attitudes, and screening behaviors among different Hispanic populations in the United States. DESIGN: Data were collected from a random digit dial telephone survey of 8903 Hispanic adults from eight U.S. sites. Across sites, the average response rate was 83%. SETTING: Data were collected as part of the baseline assessment in a national Hispanic cancer control and prevention intervention study. SUBJECTS: Analysis was restricted to 2239 Hispanic women age 40 and older who were self-identified as either Central American (n = 174), Cuban (n = 279), Mexican American (n = 1550), or Puerto Rican (n = 236). MEASURES: A bilingual survey instrument was used to solicit information on age, education, income, health insurance coverage, language use, U.S.-born status, knowledge of screening guidelines, attitudes toward cancer, and screening participation. Differences in knowledge and attitudes across Hispanic groups were assessed by either chi-square tests or analysis of variance. Logistic regression models assessed the influence of knowledge and attitudes on screening participation. RESULTS: The level of knowledge of guidelines ranged from 58.3% (Mexican Americans) to 71.8% (Cubans) for mammography, and from 41.1% (Puerto Ricans) to 55.6% (Cubans) for Pap smear among the different Hispanic populations. Attitudes also varied, with Mexican Americans and Puerto Ricans having more negative or fatalistic views of cancer than Cuban or Central Americans. Knowledge was significantly related to age, education, income, language preference, and recent screening history. Overall, attitudes were not predictive of mammography and Pap smear behavior. CONCLUSIONS: Factors related to mammography and Pap smear screening vary among the different Hispanic populations. Limitations include the cross-sectional nature of the study, self-reported measures of screening, and the limited assessment of attitudes. The data and diversity of Hispanic groups reinforce the position that ethno-regional characteristics should be clarified and addressed in cancer screening promotion efforts. The practical relationships among knowledge, attitudes, and cancer screening are not altogether clear and require further research.

Adult↗

[Dysembryoplastic neuroepithelial tumors].

INTRODUCTION: The dysembryoplastic neuroepithelial tumors tend to occur in young patients, with partial complex partial seizures which is refractory to medical treatment. These are stable lesions, with defined histological features, specially with clinical data corroboration. CLINICAL CASES: The clinical, imagiological, operative, and histopathological data of six patients with proved dysembryoplastic neuroepithelial tumors were reviewed. All patients had seizures with age at onset ranged from 7 to 27 years. Five lesions were located in the temporal lobe and one in the parietal lobe. Common features included cortical to subcortical location, low density in CT-scan, very low signal intensity on T1-weighted images and high signal on T2-weighted images. Calcification occurred in two lesions, and three showed contrast enhancement. Complete resection of the tumor was performed in three cases, and subtotal resection in other three cases. Pathological features included oligodendroglial-like cells, glioneural component, and few cases showed dysplastic cortical disorganization. The postoperative period of follow-up ranged from 2 to 18 months. Four patients were seizure free, two of which had subtotal resection of the lesion. The remaining two patients maintained seizures. CONCLUSIONS: The clinical, imagiological and histopathological data of the six cases presented are generally compatible with those of the reports reviewed by the authors. The imagiological features are nonspecific. Surgical treatment permits histological diagnosis and epilepsy control.

Adolescent↗

[Spontaneous intracranial hypotension].

The authors consider some clinical and radiological aspects of spontaneous intracranial hypotension syndrome, based on the knowledge obtained from three clinical situations. Postural headache was a constant complaint. In all cases, magnetic resonance imaging data obtained was diffuse dural enhancement and, in two cases, bilateral subdural fluid collections. The increasing recognition of this syndrome led to its distinction from meningeal inflammatory or neoplasic conditions, sparing the patient from unnecessary investigation.

Adult↗

[On research concerning abortion in Latin America and studies on women].

"Research on abortion is important for the Latin American women's movements. Rates of illegal abortion seem quite high. Cuba is the only country where abortion is legal. Policies on abortion are closely related to attitudes towards sexuality and women. Contraception has, in addition to health and economic costs, social and psychological costs, therefore unwanted pregnancies are the normal results of behavior that follows a certain rationality. Consequences of abortion depend on a woman's integration in her social network. The Latin American scene has two main differences from industrialized countries: mass poverty and the influence of the Catholic Church. Conditions of poverty affect less the motivation for abortion and more the conditions of its use." (SUMMARY IN ENG)

Abortion, Illegal↗

Dyes, preservatives and salicylates in the induction of food intolerance and/or hypersensitivity in children.

We present 25 patients, aged between 18 and 153 months, with clinical symptoms suggestive of allergy to food antigens. After undergoing exhaustive studies (including case histories, cutaneous tests for reactions to food antigen, peripheral eosinophils, secretory and humoral immunity, determination of total IgE and of specific RAST, exclusion-provocation diets) and without being able to identify an offender, patients were submitted to oral provocation with different food additives (tartrazine, sunset yellow FCF, new coccine, erythrosine, sodium benzoate, 4-methyl hydroxybenzoate and acetylsalicylic acid) after 48 hours of exclusion from their diets of dyes, preservatives and salicylates. The results obtained reflect, at a global level, 57.89% of positivities for dyes, 34.21% for the benzoates and 7.81% for acetyl-salicylic acid. The low incidence of crossed intolerance phenomena should be emphasized (32% of the patients). The disparity of our results with those of other authors could be due to the age of our patients, the clinical patterns they present and the dietary habits of different countries and regions.

Aspirin↗