RESUMO
The present work analyzes the expression of insulin receptors and theirs related intracellular signaling molecules in partially hepatectomized-diabetic rats. Insulin binding through Scatchard analysis was studied using isolated hepatocytes of Control (Sham-operated), Hepatectomized, Diabetic and Diabetic-Hepatectomized male Wistar rats. In a set of in vivo experiments, the levels of alpha subunit of the insulin receptor, the insulin receptor substrate 1 (IRS-1) and the phosphatidylinositol 3-kinase (PI3K) were determined. [3H]-thymidine incorporation into DNA 24 or 48 h after surgery was assessed in all the experimental groups. Scatchard analysis showed that insulin receptor number was increased in diabetic and in hepatectomized rats in the same extent (64%, with respect to Controls). Diabetic-hepatectomized rats showed a dramatic increase of the receptor concentration (400%) and on the affinity constant (532%). Besides, the insulin receptor expression was increased in the treated groups, being the higher values those of the diabetic-hepatectomized rats. IRS-1 and PI3K showed similar increases. DNA synthesis was not impaired by the diabetes state. In conclusion, increased expression of IR and IRS-1 leads to increased association of PI3K in vivo in diabetic regenerating rats. The enhancement of this pathway may reveal an insulin hyperresponsiveness in these animals.
Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Hepatectomia , Insulina/farmacologia , Regeneração Hepática , Animais , Sítios de Ligação , Ligação Competitiva , Contagem de Células , Sobrevivência Celular , DNA/biossíntese , Diabetes Mellitus Experimental/metabolismo , Hepatócitos/citologia , Hepatócitos/metabolismo , Técnicas In Vitro , Insulina/metabolismo , Proteínas Substratos do Receptor de Insulina , Masculino , Fosfatidilinositol 3-Quinases/metabolismo , Fosfoproteínas/metabolismo , Ratos , Ratos Wistar , Receptor de Insulina/metabolismoRESUMO
OBJECTIVE: This study determined the severity of posttraumatic stress and depressive reactions among Nicaraguan adolescents after Hurricane Mitch and the relationship of these reactions to objective and subjective features of hurricane exposure, death of a family member, forced relocation, and thoughts of revenge. METHOD: Six months after the hurricane, 158 adolescents from three differentially exposed cities were evaluated by using a hurricane exposure questionnaire, the Child Posttraumatic Stress Disorder Reaction Index, and the Depression Self-Rating SCALE: RESULTS: Severe levels of posttraumatic stress and depressive reactions were found among adolescents in the two most heavily affected cities. Severity of posttraumatic stress and depressive reactions and features of objective hurricane-related experiences followed a "dose-of-exposure" pattern that was congruent with the rates of death and destruction across cities. Level of impact (city), objective and subjective features, and thoughts of revenge accounted for 68% of the variance in severity of posttraumatic stress reaction. Severity of posttraumatic stress reaction, death of a family member, and sex accounted for 59% of the variance in severity of depression. CONCLUSIONS: After a category 5 hurricane, adolescents in heavily affected areas with extreme objective and subjective hurricane-related traumatic features of exposure experience severe and chronic posttraumatic stress and comorbid depressive reactions. The recovery of the severely affected Nicaraguan adolescents is vital to the social and economic recovery of a country ravaged by years of political violence and poverty. These findings strongly indicate the need to incorporate public mental health approaches, including systematic screening and trauma/grief-focused interventions, within a comprehensive disaster recovery program.
Assuntos
Transtorno Depressivo/epidemiologia , Desastres , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Transtornos de Adaptação/diagnóstico , Transtornos de Adaptação/epidemiologia , Transtornos de Adaptação/psicologia , Adolescente , Fatores Etários , Comorbidade , Transtorno Depressivo/diagnóstico , Transtorno Depressivo/psicologia , Desastres/estatística & dados numéricos , Feminino , Humanos , Acontecimentos que Mudam a Vida , Masculino , Nicarágua/epidemiologia , Probabilidade , Escalas de Graduação Psiquiátrica/estatística & dados numéricos , Análise de Regressão , Índice de Gravidade de Doença , Fatores Sexuais , Transtornos de Estresse Pós-Traumáticos/diagnóstico , Transtornos de Estresse Pós-Traumáticos/psicologiaRESUMO
Age-associated differences in the response of the initiation and promotion of hepatocellular carcinogenesis in the rat were analyzed. Male Wistar rats 5 and 18 months-old were used throughout. They underwent an experimental design of multistage model of hepatocarcinogenesis: hepatic cells were initiated with the complete carcinogen Aflatoxin B1 (0.5mg/Kg b.w.) and the promotion was performed through a combined treatment of proliferation (partial hepatectomy, 65%) and administration of the tumorigenic promoter phenobarbital (0.1% in drinking water for 21 days). After the treatment, rats were sacrificed and the following parameters were determined: activity and subunit composition of the glutathione S-transferase enzyme system, the number of liver preneoplastic foci and the proliferation cell index. The combined treatment (initiation + promotion) lowered the expression of the mu class GST (rGST M1, rGST M2). The inhibition in rGST M2 in old animals (which in basal conditions had already been lower) was significant. On the other hand, the treatment increased the alpha class GST (rGST A, rGST A3). The number of preneoplastic foci was higher in old rats (number of foci/cm(2): 6.9+/-0.3 vs 3.9+/-0.3 in young rats, p< 0.05). The proliferation cell index did not show age-related differences. Because rGST M2 deficiency coexisted with induced expression of alpha class, the livers would be resistant to some toxic insults, being selectively sensitive to potentially genotoxic substances for which M2 is an essential detoxification pathway. The transition to a rGST M2-deficient phenotype during aging could induce higher responsiveness to genotoxic effects, and might favor the likelihood of further progression, indicating a higher susceptibility of aged animals to the development of carcinogenesis.
Assuntos
Envelhecimento/metabolismo , Glutationa Transferase/metabolismo , Neoplasias Hepáticas Experimentais/enzimologia , Aflatoxina B1/toxicidade , Animais , Carcinógenos/toxicidade , Glutationa Transferase/química , Glutationa Transferase/classificação , Imuno-Histoquímica , Neoplasias Hepáticas Experimentais/etiologia , Masculino , Fenobarbital/toxicidade , Lesões Pré-Cancerosas/enzimologia , Lesões Pré-Cancerosas/etiologia , Antígeno Nuclear de Célula em Proliferação/metabolismo , Subunidades Proteicas , Ratos , Ratos WistarRESUMO
In order to know whether IFN alpha prevents in vivo oncogenesis in the very-early-stage cancer cells, we evaluated the action of IFN alpha-2b on preneoplastic foci in rats. Animals were divided into six groups: subjected to an initiation-promotion model of cancer development (G1), treated with IFN alpha-2b during: a) initiation-promotion (G2), b) initiation (G3), promotion (G4); subjected only to an initiation stage (G5) and treated with IFN alpha-2b during this period (G6). The number and area of rGST P-positive foci were reduced and the Apoptotic index was increased in G2, 3 and 6. Bcl-2 and Bcl-XL protein levels were decreased in IFN alpha-2b-treated rats. Increased levels of mitochondrial Bax protein were observed in G2, 3 and 6. In conclusion, preneoplastic hepatocytes in the IFN alpha-2b-treated rats undergo programmed cell death as a result of a significant increase of Bax and its translocation to the mitochondria.
Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Interferon-alfa/farmacologia , Neoplasias Hepáticas/prevenção & controle , Lesões Pré-Cancerosas/prevenção & controle , Animais , Apoptose/fisiologia , Western Blotting , Interferon alfa-2 , Fígado/enzimologia , Fígado/patologia , Masculino , Proteínas Proto-Oncogênicas/análise , Ratos , Ratos Wistar , Proteínas RecombinantesRESUMO
In order to know whether IFN alpha prevents in vivo oncogenesis in the very-early-stage cancer cells, we evaluated the action of IFN alpha-2b on preneoplastic foci in rats. Animals were divided into six groups: subjected to an initiation-promotion model of cancer development (G1), treated with IFN alpha-2b during: a) initiation-promotion (G2), b) initiation (G3), promotion (G4); subjected only to an initiation stage (G5) and treated with IFN alpha-2b during this period (G6). The number and area of rGST P-positive foci were reduced and the Apoptotic index was increased in G2, 3 and 6. Bcl-2 and Bcl-XL protein levels were decreased in IFN alpha-2b-treated rats. Increased levels of mitochondrial Bax protein were observed in G2, 3 and 6. In conclusion, preneoplastic hepatocytes in the IFN alpha-2b-treated rats undergo programmed cell death as a result of a significant increase of Bax and its translocation to the mitochondria.
RESUMO
BACKGROUND/AIMS: Clarification of the role of lipid peroxidation in the onset of liver proliferation has been hampered by the fact that both higher and lower lipid peroxidation have been reported after two-thirds partial hepatectomy. Recently, it has been shown that nitric oxide might be involved in the control of early responses after partial hepatectomy. We analysed the possible involvement of nitric oxide production in lipid peroxidation levels during liver regeneration. METHODS: Sham-operated, hepatectomised and sham and hepatectomised rats pretreated with two inhibitors of oxide nitric synthesis (aminoguanidine or N(G)-monomethyl-L-arginine) were used throughout. Animals were killed at 1, 3, 5 and 15 h after surgery. Cytosolic superoxide dismutase and microsomal-lysosomal catalase activities were measured. Lipid peroxidation levels were measured as thiobarbituric acid-reactive substances and conjugated dienes. Cytosolic nitrate (a stable metabolic product of nitric oxide) was enzymatically determined. Inducible-type nitric oxide synthase (iNOS) was analysed in hepatic cytosol by immunoblotting. DNA synthesis 24 and 48 h after surgery was assessed by [3H]thymidine incorporation. RESULTS: Increased lipid peroxidation was found in total homogenate, cytosol and microsomes. The hepatic cytosolic content of nitrates increased, reaching the highest values at 5 h posthepatectomy. Aminoguanidine or N(G)-monomethyl-L-arginine pretreatment blocked the rise of nitric oxide production and lipid peroxidation levels and decreased the DNA synthesis. The increase in hepatic iNOS protein expression at 5 h after partial hepatectomy disappeared with aminoguanidine pretreatment. CONCLUSIONS: Our experiments suggest that nitric oxide plays a role in the proliferation mechanism, although it is responsible, at least in part, for the enhanced lipid peroxidation.
Assuntos
Peroxidação de Lipídeos/fisiologia , Regeneração Hepática , Fígado/fisiologia , Óxido Nítrico/fisiologia , Animais , Divisão Celular , Fígado/patologia , Masculino , Ratos , Ratos WistarRESUMO
The relationship between asymptomatic shedding of bacterial enteropathogens and the hygiene habits of families who have had a child with typhoid fever (TF) are investigated. The sample was made up of 80 families: 40 families in which one child had had TF (Group A) and 40 in which no children or either of the parents had had a history of TF (Group B). In each group 20 families belonged to a low socioeconomic status (SES) and 20 to a high SES. A structured interview was used to evaluate the SES and the hygiene habits of the child; observations were made to measure the hygiene habits of the family (toilet, kitchen and food preparation) and bacteriological studies (fecal samples and hand markers). Results show that carriers were more frequent in Group A than in Group B. The bacterial species found were significantly more numerous in Group A than in Group B (fecal samples: E. coli, the classic serotypes, Shigella ssp, and hand markers: E. coli). Families of Group A had higher carriage rates than those of Group B. Finally there exists a significantly higher association between inadequate hygiene habits and carrier families. These results show the need to teach specific habits of proper hygiene to the entire population, because the fact of belonging to the high SES does not in itself preclude inadequate hygiene habits.
PIP: The relationship between asymptomatic shedding of bacterial enteropathogens and the hygiene habits of families who have had a child with typhoid fever (TF) are investigated. The sample was made up of 80 families: 40 in which 1 child had had TF (group A) and 40 in which no children or either of the parents had had a history of TF (group B). In each group, 20 families belonged to a low socioeconomic status (SES) and 20 to a high SES. A structured interview was used to evaluate the SES and hygiene habits of the child; observations were made to measure the hygiene habits of the family (toilet, kitchen, and food preparation) and bacteriological studies (fecal samples and handmarkers). Results show that carriers were more frequent in group A than in group B. The bacterial species found were significantly more numerous in group A than in group B (fecal samples: E. coli, the classic serotypes, Shigella ssp, and handmarkers: E. coli). Families of group A had higher carriage rates than those of group B. Finally, there exists a significantly higher association between inadequate hygiene habits and carrier families. These results show the need to teach specific habits of proper hygiene to the entire population, because of the fact of belonging to the high SES does not itself preclude inadequate hygiene habits. (author's)
Assuntos
Portador Sadio , Família , Higiene , Febre Tifoide/epidemiologia , Adolescente , Adulto , Criança , Pré-Escolar , Chile/epidemiologia , Enterobacteriaceae/isolamento & purificação , Fezes/microbiologia , Hábitos , Humanos , Lactente , Recém-Nascido , Fatores Socioeconômicos , Febre Tifoide/microbiologiaRESUMO
The goal this follow-up study was to relate the mother's marital satisfaction to family health status in a low SES. The random sample was made up of 30 families with children under 7 years old: 15 considered as sick (Group A) and 15 as healthy (Group B). Both group had similar demographic characteristics (age of father and mother, persons per family group and age of children) and SES. Results showed that mothers were those mainly in charge of their family groups. Mothers of Group A were significantly less understanding and more dissatisfied than those of Group B (p < .05 and p < .01). Mothers of Group A had significantly more arguments with their partners than those of Group B (p < .006). Health care was learned less from the child's own mother in group A than in B (p < .05). Health was considered by mothers of Group A as something that "must be taken care of" more than by those of Group B p < .01). The behaviours of mothers in choosing one of the health systems was similar in both groups. Dissatisfied mothers were associated more with sick family members during the 6 month follow-up. It is suggested that the satisfaction of the mother is a factor that needs further investigation because health is managed by mothers is the large majority of families.
Assuntos
Saúde da Família , Mães , Satisfação Pessoal , Criança , Pré-Escolar , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Nível de Saúde , Humanos , Lactente , Recém-Nascido , Masculino , Pobreza , Estudos ProspectivosRESUMO
The socio-cultural factors that might be influencing the normal psychomotor development of the undernourished infant are studied. The sample consisted of 32 mother-infant dyads: 16 having normal DQ (Group A) and 16 having a below normal DQ (Group B) according to Bailey's Test applied to infants who entered a Nutritional Recuperation Center. Results showed that there were some differences in the infants' backgrounds: infants of Group A were the product of a wished-for pregnancy (p less than .05), and were separated less from their mother's side (p less than .007) than was the case in Group B. No differences were found in the socio-cultural and demographic background of the mothers. The infants' external environment was different in aspects observed within the neighborhood: there were fewer negative aspects in Group A than in Group B (p less than .003) and more positive in Group A than in B (p less than .001). The infant's internal environment as related to the mother was also different. Mothers of Group A perceived more affection from their partner (p less than .008), were more sensitive (to feelings of joy and suffering) (p less than .003) and stimulated their infant (p less than .004) more than those of Group B. These results show that the internal and external environments in which the infant with normal and below normal DQ evolves were different between the two groups. This could explain the differences in psychomotor development among undernourished infants belonging to the lower socioeconomic strata.
Assuntos
Desenvolvimento Infantil , Transtornos da Nutrição do Lactente/complicações , Pré-Escolar , Chile , Escolaridade , Feminino , Humanos , Lactente , Masculino , Relações Mãe-Filho , Projetos Piloto , Gravidez , Transtornos Psicomotores/etiologia , Fatores SocioeconômicosRESUMO
We studied the relation of habits related to the fecal-oral cycle and incidence of typhoid fever in children attending the school system for 1 to 2 years and in their families. The goal was to identify a predictor to detect families at risk for typhoid fever. A sample of 80 school-mother dyads, 40 of high and 40 of low socio-economic status was studied. 20 children in each group had had typhoid fever. Logistic regression analysis allowed to identify dirty edges of the toilet bowl and nail eating habits as highly specific (97%) and sensitive (82%) index of risk. The predictor held both in high and low socio-economic groups and could be used to identify families at risk of developing typhoid fever.
Assuntos
Hábitos , Higiene , Febre Tifoide/transmissão , Adulto , Criança , Chile , Família , Feminino , Humanos , Masculino , Análise de Regressão , Fatores de Risco , Fatores Socioeconômicos , Febre Tifoide/prevenção & controleAssuntos
Características Culturais , Cultura , Pais , Psicologia do Adolescente , Adolescente , Criança , Chile , Feminino , Humanos , Masculino , Permissividade , Puberdade/psicologia , Punição , Educação Sexual , Fatores SocioeconômicosRESUMO
The objective of this study was to compare the sociocultural characteristics of pregnant adolescents of low SES with a nonpregnant adolescent group from the same area of Santiago, Chile. The sample was composed of 229 adolescents, 129 of whom were pregnant for the first time (group A), and 100 who were not pregnant (group B). Each pregnant girl was matched with a nonpregnant girl of the same age and from the same neighborhood. Several differences between the groups were found. Group A had less schooling, a lower level of aspirations, and tended to live in "the present." In addition, norms of behavior were more permissive, they did not practice any religion, and their peer group had more liberal attitudes. The importance of breaking these patterns in order to prevent adolescent pregnancy is discussed.
PIP: The objective of this study was to compare the sociocultural characteristics of pregnant adolescents of low socioeconomic status with a nonpregnant adolescent group from the same area of Santiago, Chile. The sample was composed of 229 adolescents, 129 of whom were pregnant for the 1st time (group A), and 100 who were not pregnant (group B). Each pregnant girl was matched with a nonpregnant girl of the same age and from the same neighborhood. Several differences between the groups were found. Group A had less schooling. It was found that the IQ of pregnant adolescents is significantly lower than that of the nonpregnant. A lower level of aspirations was also found in group A. If a girl in group A tries to improve her economic situation, which has futher deteriorated as a result of her pregnancy, she often has to do it without the help of the child's father. Group A also tended to live in the present. Further, adolescents of medium to low socioeconomic status not only leave the school system early, but live with unstable families which provide less psychosocial stimulation and an excess of free time. In addition, norms of behavior were more permissive, they did not practice any religion, and their peer group had more liberal attitudes. In sum, the pregnant adolescents are caught in a vicious cycle which must be broken by preventive actions. 1 form of such action could be specialized attention in health centers which would concentratete on all of the physical and mental health problems associated with adolescents. Another method of preventing adolescent pregnancy is to provide information about the responsibilities of becoming a parent.
Assuntos
Características Culturais , Cultura , Países em Desenvolvimento , Gravidez na Adolescência , Fatores Socioeconômicos , Adolescente , Chile , Feminino , Humanos , Grupo Associado , Gravidez , Ajustamento Social , Valores SociaisAssuntos
Cardiopatias Congênitas/epidemiologia , Chile , Feminino , Seguimentos , Humanos , Recém-Nascido , MasculinoRESUMO
The purpose of this study was to determine the degree of knowledge on food and nutrition in students graduating from high school in the Metropolitan Area of Santiago. The sample included 272 students of both sexes and type of school (public and private) and from high, medium and low socioeconomic level (SEL), measured through the Graffar Modified Scale. The degree of knowledge on food and nutrition was measured through a test of 48 items based on curriculum program objectives. The test covered three areas: Area 1, Food and Requirements; Area 2, Food, Personal and Environmental Hygiene, and Area 3, Nutritional Physiology. Students showed a good achievement of the food and nutrition objectives that are considered essential for obtaining and adequate nutrition and health status. Students from high SEL registered a significantly higher degree of knowledge on food and nutrition than students from other strata (p less than 0.001). However, sex and type of school had no effect on the degree of food and nutrition knowledge. This study is a contribution to the better understanding of factors affecting the food and nutrition knowledge, and provides good foundations for further studies.
Assuntos
Ciências da Nutrição/educação , Estudantes , Adolescente , Chile , Avaliação Educacional , Feminino , Humanos , Masculino , Fatores Sexuais , Fatores SocioeconômicosRESUMO
The aim of this study was to evaluate the degree of knowledge on food and nutrition in students graduating from Basic Education in the Metropolitan Area of Santiago, Chile. A random sample of 249 students of both sexes (1:1) from public and non-public schools (1:1) and from high, medium and low socioeconomic level (SEL), was selected. SEL was measured through the Graffar Modified Scale, and the degree of knowledge on food and nutrition was evaluated through a standardized test of 29 multiple choice items, based on the objectives of the curriculum program. The test was divided in two areas: Area 1, which contemplated Food and Requirements and Area 2, Food, Personal and Environmental Hygiene. Data were analyzed by chi-square procedure, comparing students who obtained sufficient knowledge (greater than or equal to 50% of correct answers) with those who obtained insufficient knowledge (less than 50% of correct answers). Results of the study indicated that 39.8% of students registered sufficient knowledge, 31.3% and 65.9% in Area 1 and 2, respectively. According to SEL, 62.1% and 12.3% of students from high and low SEL, respectively, registered sufficient knowledge (p less than 0.001), and the same effect was observed in Areas 1 and 2. In relation to sex, 46.3% of females and 33.3% of males registered sufficient knowledge (p less than 0.05), fact which was confirmed in both areas of the test. No significant differences were registered in the degree of knowledge on food and nutrition of students from public and non-public schools. It is therefore concluded that the degree of knowledge on food and nutrition in students graduating from Basic Education differs significantly according to SEL and, sex. This study represents a basic contribution to the better understanding of factors affecting the degree of knowledge on food and nutrition in students graduating from Basic Education in Santiago, Chile, and may serve as base-line for further studies on the subject.
Assuntos
Ciências da Nutrição/educação , Estudantes , Adolescente , Adulto , Criança , Chile , Feminino , Humanos , Masculino , Estudos de Amostragem , Fatores Sexuais , Fatores SocioeconômicosRESUMO
An anthropometric assessment of the nutritional status and growth of students graduating from Basic (8th grade) and Secondary (4th grade) Education was carried out. A group sample of 522 students from the Metropolitan Area of Santiago, Chile, was randomly selected. The same number of students by sex, dependency (public and private schools) from high, medium and low socioeconomic levels (SEL) was chosen. SEL was measured through the Graffar Modified Scale, and the percentage of weight for age (% W/A), height/age (% H/A) and weight/height (% W/H) were evaluated in accordance with the National Center for Health Statistics (NCHS) reference pattern. The % adequacy of head circumference/age (% HC/A) was determined by the Tanner Tables, and the % of upper to lower segment ratio (% US/LS), by the Tables of Muzzo et al. Results revealed that the % of W/A and of H/A were diminished in students of both sexes, while the % of UP/LS, was increased in males of low SEL, from Basic Education; this impact is lost in males graduating from Secondary Education and persists only in the LSE females. No differences in the nutritional status (% W/H) of students according to SEL, were found. Females registered values over 110% of the WHO standard, a finding suggesting a high prevalence of overweight and obesity. We conclude that there is a growth retardation in students graduating from 8th Basic Grade, which persists only in females from 4th grade of Secondary Education. This finding indicates that, in addition to possible environmental factors, other factors, probably of genetic order, also influence the latter. Overweight and obesity, therefore, constitute an important problem that merits measures of preventive nature directed to avoid future consequences.