As comunidades de formigas que vivem em fragmentos de Mata Atlântica rodeados por um ecossistema urbano bem desenvolvido, foram investigadas. Avaliou-se a riqueza, a freqüência de ocorrência das espécies bem como a similaridade entre três áreas da cidade de São Paulo: Parque da Previdência (PP), Reserva Florestal "Armando Salles de Oliveira" (CUASO) e Horto Oswaldo Cruz (HOC). Foram colocadas armadilhas do tipo "pitfall" em locais onde não ocorre visitação pública, durante uma semana, nos meses de março, junho, setembro e dezembro de 2001. Em todos os fragmentos foram coletadas 79 espécies de formigas, pertencentes a nove subfamílias e 32 gêneros. A subfamília Myrmicinae e os gêneros Pheidole e Hypoponera foram os mais ricos. No PP foram registradas 62 espécies, na CUASO 46 e no HOC 43, sendo que PP e CUASO são mais similares entre si. Tal similaridade possivelmente esteja relacionada ao tamanho de ambas as áreas e, também, a uma semelhança nos sítios de nidificação e de alimentação. No geral, a fauna de formigas é generalista, com a presença de alguns gêneros especialistas, como Discothyrea, Acanthognathus, Gnamptogenys, Oxyepoecus e Pyramica; ou de gêneros cujos hábitos alimentares ainda são desconhecidos (Heteroponera e Myrmelachista). A presença de espécies caracteristicamente de áreas domiciliares também foi constatada: Pheidole megacephala Fabricius, 1793, Linepithema humile Mayr, 1868, Wasmannia auropunctata Roger, 1863, Paratrechina fulva Mayr, 1862, P. longicornis Latreille, 1802 e Tapinoma melanocephalum Fabricius, 1793.

In this paper were investigated the ants' communities that inhabit the Atlantic Rainforest fragments surrounded by an urban ecosystem well developed. The richness, the species frequency of occurrence, as well the similarity between the three areas of the city of São Paulo were investigated: Parque da Previdência (PP), Reserva Florestal "Armando Salles de Oliveira" (CUASO) and Horto Oswaldo Cruz (HOC). Pit-fall tramps were put in places where the public visitation is not allowed, during a whole week in the months of March, June, September and December of 2001. Considering the three fragments were collected 79 ant species belonging to nine subfamilies and 32 genera. The biggest species richness was presented by the Subfamily Myrmicinae and the genera Pheidole and Hypoponera. In PP were registered 62 species, in CUASO 46 and in HOC 43. The biggest similarity was found between PP and CUASO and possibly this similarity may be due to the size of both areas and to a similarity between the sites of nesting and feeding. In general, the ants' fauna is generalist, with the presence of some specialists genera as Discothyrea, Acanthognathus, Gnamptogenys, Oxyepoecus and Pyramica or genera that have feeding habits still unknown (Heteroponera and Myrmelachista). The presence of Pheidole megacephala Fabricius, 1793, Linepithema humile Mayr, 1868, Wasmannia auropunctata Roger, 1863, Paratrechina fulva Mayr, 1862, P. longicornis Latreille, 1802 and Tapinoma melanocephalum Fabricius, 1793, species characteristic of household areas, was also observed.

To analyze whether electrocardiographic alterations (ECGA) in patients with antibodies to Trypanosoma cruzi showed a patttern of familial aggregation, a sample of 379 young adults (166 men and 213 women) distributed in sibships, were assessed for the presence of anti-T.cruzi antibodies, and subjected to a complete clinical examination and a standard resting electrocardiogram (ECG). Positive T. cruzi serology was detected in 165 individuals, 48 of them showing an abnormal ECG (overall prevalence 29 por cento). One hundred and eleven seropositive individuals were distributed in 45 sibships, each of them constituted by more than one seropositive sib, with ECGA being present in 34 out of these patients. Seropositive subjects with ECGA were detected in 27 sibships. Since the index case within each sibship is counted exactly once, affected individuals selected at random as propositi were extracted to calculate the prevalence of ECGA among first degree relatives of probands. Abnormal ECGs were recorded in 7 out of 45 sibs yielding a prevalence that did not differ from estimations registered in the general population or seropositive sibs. Data from the present sample show no familial aggregation for the occurrence of ECGA in patients with T.cruzi infection.

Estudou-se a associação de níveis plasmáticos de colesterol total, high density lipoprotein (HDL) e fow density lipoprotein (LDL), com o hábito de fumar cigarros, atividade física no trabalho e classe social em amostra aleatória de 238 homens de 18 anos de idade, de Rosario, Argentina. Os fumantes de tabaco negro, que se estavam igualmente representados nas diferentes classes sociais, apresentaram maiores níveis de colesterol total e LDL. O nível de colesterol total foi maior na classe social mais alta, o que se contrapõe com a distribuição dos fumantes por classes sociais. A associação entre atividade física no trabalho e classe social foi negativa e altamente significativa. Contrariamente não se encontraram diferenças significativas nos níveis de lipoproteínas entre os trabalhadores manuais e não manuais. É possível que as diferenças na alimentação por classes sociais ainda prevaleçam sobre o hábito de fumar quanto sua influência sobre os níveis de lipoproteínas em homens jovens.

The association of cigarette smoking, physical activity at work, and social class with total cholesterol and with high and low density lipoprotein cholesterol were examined in a random sample of 238 males, of 18 years of age, of Rosario, Argerntina. The mean (mg/dl) total serum cholesterol of the whole sample was 174.7, the high density lipoprotein cholesterol 52.8, and the low density lipoprotein cholesterol 121.5. Black tobacco consumers, evenly distributed by social class, had higher levels of total and low density lipoprotein cholesterol. Total cholesterol was higher in the high social class, differently from what smokers' distribution by social class, would lead one to expect. While a highly negative association was found between social class and physical activity at work, there were no significant diferences in lipoprotein levels between manual and non-manual workers. It is possible that the nutritional differences by social class still prevail over the smoking habit in their influence on the lipoprotein levels in these subjects.

Estudou-se a associação de níveis plasmáticos de colesterol total, high density lipoprotein (HDL) e fow density lipoprotein (LDL), com o hábito de fumar cigarros, atividade física no trabalho e classe social em amostra aleatória de 238 homens de 18 anos de idade, de Rosario, Argentina. Os fumantes de tabaco negro, que se estavam igualmente representados nas diferentes classes sociais, apresentaram maiores níveis de colesterol total e LDL. O nível de colesterol total foi maior na classe social mais alta, o que se contrapõe com a distribuição dos fumantes por classes sociais. A associação entre atividade física no trabalho e classe social foi negativa e altamente significativa. Contrariamente não se encontraram diferenças significativas nos níveis de lipoproteínas entre os trabalhadores manuais e não manuais. É possível que as diferenças na alimentação por classes sociais ainda prevaleçam sobre o hábito de fumar quanto sua influência sobre os níveis de lipoproteínas em homens jovens.

The association of cigarette smoking, physical activity at work, and social class with total cholesterol and with high and low density lipoprotein cholesterol were examined in a random sample of 238 males, of 18 years of age, of Rosario, Argerntina. The mean (mg/dl) total serum cholesterol of the whole sample was 174.7, the high density lipoprotein cholesterol 52.8, and the low density lipoprotein cholesterol 121.5. Black tobacco consumers, evenly distributed by social class, had higher levels of total and low density lipoprotein cholesterol. Total cholesterol was higher in the high social class, differently from what smokers' distribution by social class, would lead one to expect. While a highly negative association was found between social class and physical activity at work, there were no significant diferences in lipoprotein levels between manual and non-manual workers. It is possible that the nutritional differences by social class still prevail over the smoking habit in their influence on the lipoprotein levels in these subjects.

Rosario, with a million inhabitants, is the second major urban concentration in Argentina and serves as the commercial and industrial center for a large area. In view of the lack of information on the present prevalence of smoking in this area as for the country as a whole, a study was performed on random samples of young people and university students of medicine and economics, as well as on their parents. Information was obtained on their life smoking habits, education and occupation. The prevalence of the habit was higher: a) in men, both in the youngsters and their parents; b) in medical students than in those of the economic sciences; c) in parents with university education. The smoking habit of these subjects and parents was highly associated (p < 0.001) in the sample of young people, although no association was found between the prevalence of smoking among university students and their parents. Peer smoking was the main factor influencing the onset of cigarette smoking given by 69% of the subjects. Knowledge of specific adverse health effects of smoking was poor. Attitudes toward restrictive measures were highly associated (p < 0.001) with the non-smoker category. Based on these findings, we conclude that while there is a need for educational programs for the population in general, the university as a whole and specifically the school of medicine should implement a program to increase knowledge and awareness on this public health problem.

Con el objetivo de conocer la prevalencia del hábito de fumar cigarrillos en los jóvenes, se estudiaron muestras aleatorias de varones de 18 años y de estudiantes universitarios de medicina y de economía, los que respondieron un cuestionario referido al hábito, escolaridad y ocupación propias y de sus padres, así como sus opiniones y motivaciones. La prevalencia del hábito fue mayor en los varones en ambas generaciones, en los estudiantes de medicina que en los de economía, y en los padres con nivel universitario. Se encontró asociación entre el hábito de los jóvenes de la problación general con el de sus padres (p<0.001), pero no entre el de éstos y sus hijos universitarios. Considerando el rol protagónico que los universitarios y en especial los médicos deberían cumplir en la comunidad, surge la necesidad del desarrollo de programas educativos no sólo en las escuelas sino también en la universidad.

Com o objetivo de conhecer a prevalência de hábito de fumar cigarros entre os jovens, estudaram-se amostras aleatórias de homens de 18 anos e de estudantes universitários de medicina e de economia, que responderam um questionário sobre o hábito, escolaridade e ocupação, próprios e de seus pais. A prevalência do hábito de fumar foi maior nos homens de ambas as gerações, nos estudantes de medicina, que nos de economia, e nos pais com educação universitária. Achou-se associação entre o hábito dos jovens representativos da população geral (p < 0,001), mas não entre o dos progenitores e de seus filhos universitários. Visto a participação fundamental que os universitários, em especial os médicos, deveriam ter na comunidade, surge a necessidade de programas educativos, não só nas escolas mas também nas universidades.

Com o objetivo de conhecer a prevalência de hábito de fumar cigarros entre os jovens, estudaram-se amostras aleatórias de homens de 18 anos e de estudantes universitários de medicina e de economia, que responderam um questionário sobre o hábito, escolaridade e ocupação, próprios e de seus pais. A prevalência do hábito de fumar foi maior nos homens de ambas as gerações, nos estudantes de medicina, que nos de economia, e nos pais com educação universitária. Achou-se associação entre o hábito dos jovens representativos da população geral (p < 0,001), mas não entre o dos progenitores e de seus filhos universitários. Visto a participação fundamental que os universitários, em especial os médicos, deveriam ter na comunidade, surge a necessidade de programas educativos, não só nas escolas mas também nas universidades.

Rosario, with a million inhabitants, is the second major urban concentration in Argentina and serves as the commercial and industrial center for a large area. In view of the lack of information on the present prevalence of smoking in this area as for the country as a whole, a study was performed on random samples of young people and university students of medicine and economics, as well as on their parents. Information was obtained on their life smoking habits, education and occupation. The prevalence of the habit was higher: a) in men, both in the youngsters and their parents; b) in medical students than in those of the economic sciences; c) in parents with university education. The smoking habit of these subjects and parents was highly associated (p < 0.001) in the sample of young people, although no association was found between the prevalence of smoking among university students and their parents. Peer smoking was the main factor influencing the onset of cigarette smoking given by 69% of the subjects. Knowledge of specific adverse health effects of smoking was poor. Attitudes toward restrictive measures were highly associated (p < 0.001) with the non-smoker category. Based on these findings, we conclude that while there is a need for educational programs for the population in general, the university as a whole and specifically the school of medicine should implement a program to increase knowledge and awareness on this public health problem.

Con el objetivo de conocer la prevalencia del hábito de fumar cigarrillos en los jóvenes, se estudiaron muestras aleatorias de varones de 18 años y de estudiantes universitarios de medicina y de economía, los que respondieron un cuestionario referido al hábito, escolaridad y ocupación propias y de sus padres, así como sus opiniones y motivaciones. La prevalencia del hábito fue mayor en los varones en ambas generaciones, en los estudiantes de medicina que en los de economía, y en los padres con nivel universitario. Se encontró asociación entre el hábito de los jóvenes de la problación general con el de sus padres (p<0.001), pero no entre el de éstos y sus hijos universitarios. Considerando el rol protagónico que los universitarios y en especial los médicos deberían cumplir en la comunidad, surge la necesidad del desarrollo de programas educativos no sólo en las escuelas sino también en la universidad.

The present study was undertaken in order to demonstrate that reinfection could modify parasitemia, serum antibodies, electrocardiographic patterns and/or myocardial lesions already observed in a rat model. Experimental groups IG: rats infected at weaning with 1 x 10(6) T. cruzi; RG: same as IG plus reinoculations each 30 days until completion on day 150; IG1: 51 day old infected rats; C: controls. A high parasitemia was detected in IG and RG until day 20 showing a tendency to become negative on day 30. No parasites were observed in RG after the first reinoculation which could not be attributed to the old age of the host since there was no parasitemia in IG1. Xenodiagnoses were negative in all three groups. Serum antibodies were not significantly modified in RG in comparison with IG, except for 7S antibodies, since RG showed higher titres in some days under study. No distinct patterns of basal ECG were observed in infected rats. The ajmalina test reduced the heart rate (HR) showing no treatment dependance. The PR, QaT and QRS were significantly lengthened in all groups regarding the basal one (p < 0.05), except for the QaT in C. Besides, the PR and QaT alterations were greater in the infected rats (p< 0.05). There was also present a wide variety of electric axis orientations, regarding the basal value, accompanied by morphological changes more evident in the RG. The incidence of cardiac lesions histologically detected in the infected group was significantly higher than in C (p < 0.01). It can be concluded that reinfection, neither produce the onset of acute initial disorders nor modify the type or degree of cardiac lesion histologically observed. The ajmaline test showed ECG alterations compatible with a mild myocardial damage in infected rats, whereas a major compromise was assessed in the reinfected group.

El objetivo de este trabajo fue comprobar si una de las variables medio-ambientales, la reinfección, puede modificar el comportamiento observado en un modelo de rata a nivel de parasitemia, anticuerpos séricos, manifestaciones electrocardiográficas y/o lesión miocárdica. Los grupos experimentales fueron: GI: ratas infectadas al destete con 1 x 10(6) T. cruzi; GR: igual a GI más reinfecciones cada 30 días hasta los 150 días post-infección inicial (p.i.i.); GI1 ratas de 51 días infectadas; GT: testigos. Se detectó parasitemia alta en GI y GR hasta los 20 días p.i.i. tendiendo a negativizarse al día 30. En GR no se observaron parásitos despúes del primer reinóculo, resistencia que no es debida sólo a la mayor edad del huésped pués hubo parasitemia en GI1. Los xenodiagnósticos fueron negativos en los tres grupos. Los anticuerpos séricos no se modificaron significativamente en GR respecto de GI, salvo en los anticuerpos 7S, pues los del GR presentaron títulos superiores en algunos de los días estudiados. Los ECG basales no mostraron cambios distintivos en las ratas infectadas. La prueba de ajmalina mostró una disminución de la FC independiente del tratamiento; el PR, QaT y QRS se prolongaron significativamente en todos los grupos respecto del basal (p < 0.05), salvo el QaT en el GT; además, el cambio de PR y QaT fue mayor en los infectados (p < 0.05). En los grupos infectados hubo también una amplia variación en la orientación del eje eléctrico respecto del valor basal, acompañado de cambios morfológicos más manifiestos en GR. La proporción de lesión cardíaca detectada histológicamente en los grupos infectados, fue significativamente superior a la del GT (p < 0.01). Se concluye que la reinfección no reproduce el cuadro agudo inicial y no modifica el tipo y grado de lesión cardíaca observada histológicamete. La prueba de ajmalina muestra cambios electrocardiográficos compatibles con daño miocárdico incipiente en las ratas infectadas y sugieren mayor compromiso en el grupo reinfectado.

The experimental arthritis produced in rats which had been infected at weaning with Trypanosoma cruzi was studied 90 days after inoculation. Focal arthritis was induced by injecting 0.1 ml of Freund complete adjuvant in one hind foot-pac of inbred previously treated animals and controls. To measure different degrees of foot-pad inflammation and swelling a semi quantitative scale was used. Furthermore, a histopathological study of heart and joints was performed 180 days after T. cruzi inoculation. The joint injury in the T. cruzi group was significantly smaller than in the controls, during the acute period (p < 0.001). Histopathologic observations showed local tissue inflammatory infiltration with lymphocytes, plasma cells and macrophages. These pathological changes observed in treated animals were also smaller than in the controls, (p < 0.001). It is postulated that in chagasic rats the less severe arthritis could be due to an antigenic competition or immunosuppressive mechanisms present in infected animals.

Se estudió la evolución de la artritis por adyuvante en ratas que habían sido infectadas previamente con Trypanosoma cruzi, con el objeto de evaluar su competencia inmunológica a través de la respuesta artrítica. La artritis por adyuvante se indujo en ratas adultas, endocriadas de ambos sexos, con 0.1 mi de adyuvante completo de Freund en la almohadilla plantar, en 2 lotes: a) inyectadas 90 días antes con 1 x 10(6) T. cruzi y b) testigos normales simultáneos. Se midieron, la lesión artrítica macroscópicamente con una escala semicuantitativa, y con microscopía óptica la histopatología de la lesión local y la del corazón, a los 180 días post-infecoión. La magnitud de las lesiones artríticas en las ratas con T. cruzi fue significativamente menor (p < 0.001) que la de los testigos, en todo el período. El infiltrado inflamatorio local, formado por linfocitos, plasmocitos y macrófagos fue significativamente menor (p < 0.001) en las ratas chagásicas, con respecto al de los testigos. Se postula que en las ratas que recibieron T. cruzi la respuesta artrítica menor podría deberse a una competición antigénica con los determinantes del parásito o a mecanismos inmunosupresores que interfieren en la producción de la entidad experimental.