Estimate of DMFT index using teeth most affected by dental caries in twelve-year-old children

The objective of the study was to develop regression models to describe the epidemiological profile of dental caries in 12-year-old children in an area of low prevalence of caries. Two distinct random probabilistic samples of schoolchildren (n=1,763) attending public and private schools in Piracicaba, Southeastern Brazil, were studied. Regression models were estimated as a function of the most affected teeth using data collected in 2005 and were validated using a 2001 database. The mean (SD) DMFT index was 1.7 (2.08) in 2001 and the regression equations estimated a DMFT index of 1.67 (1.98), which corresponds to 98.2% of the DMFT index in 2001. The study provided detailed data on the caries profile in 12-year-old children by using an updated analytical approach. Regression models can be an accurate and feasible method that can provide valuable information for the planning and evaluation of oral health services.

Contextual and individual indicators associated with the presence of teeth in adults

OBJECTIVE The objective of this study was to analyze whether socioeconomic conditions and the period of availability of fluoridated water are associated with the number of teeth present.METHODSThis cross-sectional study analyzed data from 1,720 adults between 20 and 59 years of age who resided in Florianópolis, SC, Southern Brazil, in 2009. The outcome investigated was the self-reported number of teeth present. The individual independent variables included gender, age range, skin color, number of years of schooling, and per capita household income. The duration of residence was used as a control variable. The contextual exposures included the period of availability of fluoridated water to the households and the socioeconomic variable for the census tracts, which was created from factor analysis of the tract’s mean income, education level, and percentage of households with treated water. Multilevel logistic regression was performed and inter-level interactions were tested.RESULTS Residents in intermediate and poorer areas and those with fluoridated water available for less time exhibited the presence of fewer teeth compared with those in better socioeconomic conditions and who had fluoridated water available for a longer period (OR = 1.02; 95%CI 1.01;1.02). There was an association between the period of availability of fluoridated water, per capita household income and number of years of education. The proportion of individuals in the poorer and less-educated stratum, which had fewer teeth present, was higher in regions where fluoridated water had been available for less time.CONCLUSIONS Poor socioeconomic conditions and a shorter period of availability of fluoridated water were associated with the probability of having fewer teeth in adulthood. Public policies aimed at reducing socioeconomic inequalities and increasing access to health services such as fluoridation of the water supply may help to reduce tooth loss in the future.

Chronic myocardial damage in experimental T. cruzi infection of a new world primate, Cebus sp. monkey

Eighteen Cebus apella monkeys, (juvenile and adult of both sexes) were inoculated five years ago, with three Trypanosoma cruzi strains (CA1, n = 10; Colombian, n=4 and Tulahuen, n=4), either by conjunctival or intraperitoneal route, once or repeatedly. Parasitological, hematological, serological, enzymatic, radiographic, electro and echocardiographic findings have been peviously published15 and they are similar to those observed in human pathology. The most frequent electrocardiographic alteration was right branch bundle block. Six animals, chosen at random, were sacrificed. Those sacrificed 20 to 25 months post-first inoculation showed focal accumuli of leukocytes with myocytolysis. Foci of diffuse interstitial fibrosis with mild infiltrate of leukocytes among fibers were observed in the animals sacrificed 36 to 47 months post-inoculation. No parasites were seen. The lesions were more prominent in the ventricular walls and the septum. The fact that the infiltrates were predominant in the animals sacrificed at a shorter time after first inoculation and that fibrosis was more severe in those sacrificed at a longer time suggests that there is a progression of the infiltrative lesions to fibrosis, with a leukocytic activity indicative of a chronic phase. These lesions are similar to those described in human chronic Chagas' disease. This would demonstrate that this model is useful in evaluating a progress in the knowledge of the pathogenesis which is still a controversial issue, immunology, immunogenesis and chemotherapeutic agents of the chronic and indeterminate phases of this disease.

Gastric acid secretion response in the Cebus apella: a monkey model of chronic Chagas disease

The objective was to study the secretory pattern, both basal and stimulated either by histamine (0.1 mg/kg) or pentagastrin (64 ug/kg) in eighteen Cebus apella monkeys chronically infected with different T. cruzi strains (CA1, n=10; Colombian, n=4 and Tulahuen, n=4) and to describe the morphological findings in the gastrointestinal tract in twelve infected (6 sacrificed and 6 spontaneously dead) and four healthy monkeys. All infected monkeys and 35 healthy ones were evaluated by contrast X-ray examination. No differences were observed in basal acid output between control and infected groups. Animals infected with the Tulahuen and Colombian strains showed significant lower values of peak acid output in response to histamine or pentagastrin (p<0.01 and p<0.05 respectively; "t" test) in comparison to the controls. Barium contrast studies showed enlargement and dilatation of the colon in three infected animals. Histopathological lesions were seen in 75% of the autopsied animals either in colon alone (33%) or both, in colon and esophagus (42%). The normal secretion observed in the CA1 infected group could be due to a lower virulence of the strain, a lower esophagic tropism or the necessity of a longer post-infection time to cause lesions.

A preliminary investigation on the gastrointestinal helminths of the Barbados green monkey, Cercopithecus aethiops sabaeus

Faecal samples were collected from fifty three freshly captured monkeys which were kept at the Barbados Primate Research Centre and Wildlife Reserve (BPRCWR). Examination of these samples for gastrointestinal helminths using the zinc sulphate floatation method revealed an overall infection rate of 88.7%.The parasites observed included Strongyloides (62.4%), Physaloptera (58.5%), Trichuris (52.8%), Hookworm (34.0%), Oesophagostomum (30.2%), Trichostrongylus (3.8%) and Ascaris (5.7%). No significant differences in overall prevalence were observed according to sex or age. Polyparasitism appeared to be common as it was observed in 92.5% of all monkeys examined. It is concluded that these monkeys could act as reservoirs of some of the parasites which can infect man.

Susceptibility of Cebus apella monkey (Primates: Cebidae) to experimental Leishmania (L.) infantum chagasi-infection

In Amazonian Brazil, the Cebus apella monkey (Primates: Cebidae) has been associated with the enzootic cycle of Leishmania (V.) shawi, a dermotropic parasite causing American cutaneous leishmaniasis (ACL). It has also been successfully used as animal model for studying cutaneous leishmaniasis. In this work, there has been investigated its susceptibility to experimental Leishmania (L.) infantum chagasi-infection, the etiologic agent of American visceral leishmaniasis (AVL). There were used ten C. apella specimens, eight adult and two young, four males and six females, all born and raised in captivity. Two experimental infection protocols were performed: i) six monkeys were inoculated, intra-dermal via (ID), into the base of the tail with 2 x 10(6) promastigotes forms from the stationary phase culture medium; ii) other four monkeys were inoculated with 3 x 10(7) amastigotes forms from the visceral infection of infected hamsters by two different via: a) two by intravenous via (IV) and, b) other two by intra-peritoneal via (IP). The parameters of infection evaluation included: a) clinical: physical exam of abdomen, weigh and body temperature; b) parasitological: needle aspiration of the bone-marrow for searching of amastigotes (Giemsa-stained smears) and promastigotes forms (culture medium); c) immunological: Indirect fluorescence antibody test (IFAT) and, Delayed-type hypersensitivity (DTH). In the six monkeys ID inoculated (promastigotes forms) all parameters of infection evaluation were negative during the 12 months period of follow-up. Among the four monkeys inoculated with amastigotes forms, two IV inoculated showed the parasite in the bone-marrow from the first toward to the sixth month p.i. and following that they cleared the infection, whereas the other two IP inoculated were totally negative. These four monkeys showed specific IgG-antibody response since the third month p.i. (IP: 1/80 and IV: 1/320 IgG) toward to the 12th month (IP: 1/160 and IV: 1/5120). The DTH-conversion occurred in only one IV inoculated monkey with a strong (30 mm) skin reaction. Considering these results, we do not encourage the use of C. apella monkey as animal model for studying the AVL.

Habitat preferences, diet, feeding strategy and social organization of the black spider monkey [Ateles paniscus paniscus Linnaeus 1758] in Surinam

A Socioecological Field Study.This monograph reports on a 26 month socioecological study of black spider monkeys (Ateles paniscus paniscus)in the Raleigh-vallen — Voltzberg Nature Reserve, Surinam. It recognizes the fundamental importance of food to the behavior and the regulation of population density fox this primate. It clarifies the complex temporal and spatial effects of tropical rain forest food sources on the behavior of a group of spider monkeys, concentrating on food category, food plant identity and phenology, and quantity, density and dispersion of the most important food sources. In addition, the present study describes habitat choice, optimal feeding strategy and sexual behavior of the spider monkey, and discusses implications of diet for social behavior. This study is also fundamental to conservation. Specialized in eating mature fruits, the spider monkey is a very important dispersal agent for many trees and lianes, particularly canopy species. However, the spider monkey is probably the most vulnerable monkey species in Surinam and it is disappearing rapidly throughout the remainder of its range. Unfortunately, it is large and noisy and can be easily tracked and hunted. It is largely restricted to undisturbed high forest, and consequently habitat destruction has more effect on it than on most other species. Together with its slow reproductive rate (a female gives birth only once every four or five years), this means that the species is poorly adapted to recover from exploitation. In order to implement proper measures for conservation, data on forest type preferences, diet and social behavior of the species, or on closely related species, in undisturbed areas, such as the one described in this monograph, are essential tools for assessing the potential of proposed protected areas.

Histological study of capuchin monkey (Cebus apella) ovarian follicles

The present study aimed to obtain quanti-qualitative data about the follicular ovarian population in Cebus apella females. Seven ovaries were obtained from 4 C. apella adult females. The ovaries were subjected to light microscopy. The number of preantral and antral follicles for each ovary was estimated using the Fractionator method. The preantral follicles were classified into primordial, transitional, primary and secondary follicles. Antral follicles were those that presented an antral cavity. All counted follicles were classified as normal or degenerated. The diameter of the follicles, oocytes and their nuclei were determined to accompany the follicular development. All results were represented as mean ± SE. The number of preantral follicles was 56,938 ± 21,888 and 49,133 ± 26,896 for the right and left ovaries, respectively. The percentage of normal follicles was 80 ± 4.95%. The follicular diameter ranged from 22 ± 0.5 µm to 61.2 ± 4.0 µm. Regarding the antral follicles, the number of normal and degenerate follicles per ovary were 60.0 ± 19.0 and 3 ± 1.8 follicles, respectively. The antral follicular diameter was 514.4 + 56.6 µm. In conclusion, the information obtained in this study can be used as a parameter for subsequent in vivo or in vitro studies about folliculogenesis in non-human neotropical primates of the C. apella species.

The effects of introducing the Amazonian squirrel monkey on the behavior of the northeast marmoset

The squirrel monkey Saimiri sciureus, an endemic primate of the Amazonian Basin, has been introduced in many localities of the Atlantic Forest biome. Introduced exotic species gain a competitive advantage in their new environment because of a lack of natural predators, competitors or diseases. This advantage can result in a reduction in the resources for the endemic species. The aims of this work were to evaluate the level of adaptation, and monitor the forms of interaction and the impact caused by S. sciureus on the behavior of the native species Callithrix jacchus in the Saltinho Biological Reserve, Tamandaré, Pernambuco, Brazil. The behavior was assessed by use of scan sampling method, every 5 min. A total of 382 h (191 h or 2,292 scans per group) of time sampling was performed. Sixteen interactions were recorded. The interaction index was low and represented 2.4% of the total observation time. Interactions were significantly higher during the dry season (58.5%) relative to the rainy season (41.5%). Callithrix jacchus was intolerant to the presence of S. sciureus and the last one was more tolerant during the interactions. In the presence of S. sciureus, C. jacchus eating, foraging, resting, socializing, and self-grooming behaviors were reduced while alertness was increased. Territorial behavior showed no significant difference. In the presence of S. sciureus, on average, the group of marmosets assembled at a higher layer of the forest stratum. The results might indicate a negative effect of S. sciureus on the native species, C. jacchus.

Primatology in southern Brazil: a transdisciplinary approach to the conservation of the brown-howler-monkey Alouatta guariba clamitans (Primates, Atelidae)

Human interventions in natural environments are the main cause of biodiversity loss worldwide. The situation is not different in southern Brazil, home of five primate species. Although some earlier studies exist, studies on the primates of this region began to be consistently carried out in the 1980s and have continued since then. In addition to important initiatives to study and protect the highly endangered Leontopithecus caissara Lorrini & Persson, 1990 and Brachyteles arachnoides E. Geoffroy, 1806, other species, including locally threatened ones, have been the focus of research, management, and protection initiatives. Since 1993, the urban monkeys program (PMU, Programa Macacos Urbanos) has surveyed the distribution and assessed threats to populations of Alouatta guariba clamitans (Cabrera, 1940) in Porto Alegre and vicinity. PMU has developed conservation strategies on four fronts: (1) scientific research on biology and ecology, providing basic knowledge to support all other activities of the group; (2) conservation education, which emphasizes educational presentations and long-term projects in schools near howler populations, based on the flagship species approach; (3) management, analyzing conflicts involving howlers and human communities, focusing on mitigating these problems and on appropriate relocation of injured or at-risk individuals; and finally, (4) Public Policies aimed at reducing and/or preventing the impact of urban expansion, contributing to create protected areas and to strengthen environmental laws. These different approaches have contributed to protect howler monkey populations over the short term, indicating that working collectively and acting on diversified and interrelated fronts are essential to achieve conservation goals. The synergistic results of these approaches and their relationship to the prospects for primatology in southern Brazil are presented in this review.

Polymorphism in Trypomastigotes of Trypanosoma (Megatrypanum) minasense in the blood of experimentally infected squirrel monkey and marmosets

Experimental infections by Trypanosoma (Megatrypanum) minasense were performed in primates - Saimiri sciureus and Callithrix penicillata - with the objective of searching for morphological variations of the blood trypomastigotes with respect to hosts and time of infection. We carried out morphological and morphometric analysis of blood trypomastigotes. Illustrations are given. Both the squirrel monkey and marmoset became infected after the injection of blood trypomastigotes of T. minasense , although the parasitaemia were briefer in the squirrel monkey. The parasites detected in the later host were narrower and shorter than those found in the inoculated marmoset. In the marmoset, the blood stream parasites derived from culture metacyclic trypomastigotes were considerably smaller than those derived from the inoculation of infected blood. Stronger evidence of polymorphism was found when, at the same time of infection, the blood trypomastigotes found in squirrel monkey had smaller length, body width and the distance from posterior end of the body to the kinetoplast almost four times smaller than the parasite found in the marmoset. Therefore, conflicting results on morphology and morphometry of T. minasense obtained by previous investigators could be due to polymorphism.

Aotus infulatus monkey is susceptible to Plasmodium falciparum infection and may constitute an alternative experimental model for malaria

Aotus is one of the WHO-recommended primate models for studies in malaria, and several species can be infected with Plasmodium falciparum or P. vivax. Here we describe the successful infection of the species A. infulatus from eastern Amazon with blood stages of P. falciparum. Both intact and splenectomized animals were susceptible to infection; the intact ones were able to keep parasitemias at lower levels for several days, but developed complications such as severe anemia; splenectomized monkeys developed higher parasitemias but no major complications. We conclude that A. infulatus is susceptible to P. falciparum infection and may represent an alternative model for studies in malaria.

Study of the safety, immunogenicity and efficacy of attenuated and killed Leishmania (Leishmania) major vaccines in a rhesus monkey (Macaca mulatta) model of the human disease

We have compared the efficacy of two Leishmania (Leishmania) major vaccines, one genetically attenuated (DHFR-TS deficient organisms), the other inactivated [autoclaved promastigotes (ALM) with bacillus Calmete-Guérin (BCG)], in protecting rhesus macaques (Macaca mulatta) against infection with virulent L. (L.) major. Positive antigen-specific recall proliferative response was observed in vaccinees (79% in attenuated parasite-vaccinated monkeys, versus 75% in ALM-plus-BCG-vaccinated animals), although none of these animals exhibited either augmented in vitro gamma interferon (IFN-g) production or positive delayed-type hypersensitivity (DTH) response to the leishmanin skin test prior to the challenge. Following challenge, there were significant differences in blastogenic responses (p < 0.05) between attenuated-vaccinated monkeys and naïve controls. In both vaccinated groups very low levels of antibody were found before challenge, which increased after infective challenge. Protective immunity did not follow vaccination, in that monkeys exhibited skin lesion at the site of challenge in all the groups. The most striking result was the lack of pathogenicity of the attenuated parasite, which persisted in infected animals for up to three months, but were incapable of causing disease under the conditions employed. We concluded that both vaccine protocols used in this study are safe in primates, but require further improvement for vaccine application.