Estimation of Aedes aegypti (Diptera: Culicidae) population size and adult male survival in an urban area in Panama

Traditional mosquito control strategies rely heavily on the use of chemical insecticides. However, concerns about the efficiency of traditional control methods, environmental impact and emerging pesticide resistance have highlighted the necessity for developing innovative tools for mosquito control. Some novel strategies, including release of insects carrying a dominant lethal gene (RIDL®), rely on the sustained release of modified male mosquitoes and therefore benefit from a thorough understanding of the biology of the male of the species. In this report we present the results of a mark-release-recapture study aimed at: (i) establishing the survival in the field of laboratory-reared, wild-type male Aedes aegypti and (b) estimating the size of the local adult Ae. aegypti population. The study took place in Panama, a country where recent increases in the incidence and severity of dengue cases have prompted health authorities to evaluate alternative strategies for vector control. Results suggest a life expectancy of 2.3 days for released male mosquitoes (confidence interval: 1.78-2.86). Overall, the male mosquito population was estimated at 58 males/ha (range 12-81 males/ha), which can be extrapolated to an average of 0.64 pupae/person for the study area. The practical implications of these results are discussed.

Genetic improvement and population structure of the Nelore breed in Northern Brazil

The objective of this work was to evaluate the population structure and the genetic and phenotypic progress of Nelore cattle in Northern Brazil. Pedigree information concerning animals born between 1942 and 2006 were analyzed. Population structure was performed using the Endog program. Out of the 140,628 animals studied, 67.7, 14.52 and 3.18% had complete pedigree record of the first, second and third parental generation, respectively. Inbreeding and average relatedness coefficients were low: 0.2 and 0.13%, respectively. However, these parameters may have been underestimated, since information on pedigree was incomplete. The effective number of founders was 370 and the genetic contribution of 10, 50 and 448 most influent ancestors explained 13.2, 28 and 50% of the genetic variability in the population, respectively. The genetic variability for growth traits and population structure demonstrates high probability of increasing productivity through selective breeding. Moreover, management strategies to reduce the currently observed age at first calving and generation intervals are important for Nelore cattle genetic improvement.

Genetic structure and diversity of Copaifera langsdorffii Desf. in Cerrado fragments of the São Paulo State, Brazil

The loss of large areas of Cerrado (Brazilian savanna) in Brazil can lead to reduced biodiversity and to the extinction of species. Therefore, the present study aimed to investigate the genetic fragility of populations of Copaifera langsdorffii Desf exposed to different anthropic conditions in fragments of Cerrado in the state of São Paulo. The study was carried out in two Experimental Stations operated by the Forest Institute (Assis and Itirapina), in one fully protected conservation unit (Pedregulho) and in one private property (Brotas). Analyses were conducted using leaf samples from 353 adult specimens and eight pairs of microsatellite loci. The number of alleles per locus ranged from 13 to 15 in all populations, but the mean number of effective alleles was approximately half this value (7.2 to 9-1). Observed heterozygosity was significant and lower than the expected in all populations. Consequently, all populations deviated from Hardy-Weinberg expected frequencies. Fixation indexes were significant for all populations, with the Pedregulho population having the lowest value (0.189) and Itirapina having the highest (0.283). The analysis of spatial genetic structure detected family structures at distance classes of 20 to 65 m in the populations studied. No clones were detected in the populations. Estimates of effective population size were low, but the area occupied by each population studied was large enough for conservation, medium and long term. Recent reductions or bottlenecks were detected in all four populations. Mean Gst’ (genetic divergence) indicated that most of the variation was within populations. Cluster structure analysis based on the genotypes detected K= 4 clusters with distinct allele frequencies patterns. The genetic differentiation observed among populations is consistent with the hypothesis of genetic and geographic isolation. Therefore, it is essential to adopt conservation strategies that raise the gene flow between fragments.

Genetic characterization of ninety elite soybean cultivars using coefficient of parentage

The objective of this work was to estimate the coefficient of parentage and to understand the genetic structure of 90 elite soybean cultivars, which are adapted to different Brazilian environments. A total of 4,005 coefficients of parentage (f) were obtained and used to group the cultivars by UPGMA method. The constructed dendrogram showed several related cultivar groups which shared similar ancestors and clearly showed the genetic structure of the main Brazilian cultivars. Effective population sizes (Ne) were also estimated for cultivars in different generations. The average f = 0.2124 value, obtained from cultivars classified into four decades according to the release year, suggested effective soybean population sizes of 11 and 13 calculated using arithmetic and weighted means, respectively. The relatively small Ne and the high parentage coefficient support the conclusion that there is a high similarity degree among the main soybean cultivars in Brazil.

Genetic parameters and estimated genetic gains in young rubber tree progenies

The objective of this work was to assess the genetic parameters and to estimate genetic gains in young rubber tree progenies. The experiments were carried out during three years, in a randomized block design, with six replicates and ten plants per plot, in three representative Hevea crop regions of the state of São Paulo, Brazil. Twenty-two progenies were evaluated, from three to five years old, for rubber yield and annual girth growth. Genetic gain was estimated with the multi-effect index (MEI). Selection by progenies means provided greater estimated genetic gain than selection based on individuals, since heritability values of progeny means were greater than the ones of individual heritability, for both evaluated variables, in all the assessment years. The selection of the three best progenies for rubber yield provided a selection gain of 1.28 g per plant. The genetic gains estimated with MEI using data from early assessments (from 3 to 5-year-old) were generally high for annual girth growth and rubber yield. The high genetic gains for annual girth growth in the first year of assessment indicate that progenies can be selected at the beginning of the breeding program. Population effective size was consistent with the three progenies selected, showing that they were not related and that the population genetic variability is ensured. Early selection with the genetic gains estimated by MEI can be made on rubber tree progenies.

Conservação genética de populações de Cryptocarya moschata Nees (Lauraceae) na Mata Atlântica do estado de São Paulo

Através da análise de 18 locos isoenzimáticos polimórficos, foram estimadas as freqüências alélicas referentes a 214 indivíduos adultos de quatro populações naturais de Cryptocarya moschata de duas regiões do estado de São Paulo. Com base nas heterozigosidades observadas e esperadas, foram obtidas estimativas das estatísticas F de Wright. Para fins de comparação, utilizou-se também o método da análise da variância para estimação dos parâmetros correspondentes F = FIT, qP= FST e f = FIS. Os dois métodos forneceram resultados bastante concordantes: IT = 0,142; ST = 0,140; IS = 0,002 e = 0,116; P = 0,123 e = ­0,008, indicando que os indivíduos dentro das populações devem ser panmíticos e que a diversidade entre populações é bastante alta, sendo similar à que se espera para famílias com estruturação de meios-irmãos. Calculando P com as populações tomadas duas a duas, notou-se tendência de P crescer com a distância geográfica o que sugere tendência de isolamento pela distância. O fluxo gênico foi estimado em 0,9 indivíduos por geração, o que corrobora a pronunciada diferenciação populacional encontrada. Devido ao valor negligível encontrado de IS, o tamanho efetivo de variância de cada população é equivalente ao número de indivíduos amostrados. As estratégias de manejo e conservação necessárias para a preservação da alta variabilidade genética intrapopulacional de C. moschata implicam na manutenção de populações com número grande de indivíduos. Além disso, para a preservação da espécie como um todo, a manutenção de muitas populações provavelmente é necessária.

Mating system in Myracrodruon urundeuva (Anarcadiaceae): implications for conservation genetics

The aims of this study were to investigate the mating system of a fragmented population of the dioecious tropical tree Myracrodruon urundeuva Allemão, using five microsatellite loci and the mixed mating and correlated mating models. The study was conducted in the Estação Ecológica de Paulo de Farias (436 ha), where the population occupies about 142 ha. The mating system was estimated using 514 open-pollinated offspring, collected from 30 seed-trees. Estimates of the multilocus outcrossing rate confirm that the species is dioecious (t m = 1.0). Low levels of mating among relatives were detected in the population (1 - t s = 0.020). The estimate of paternity correlation (r p(m)) indicated that offsprings were composed of mixtures of half-sibs and full-sibs, with the latter occurring at a low frequency (average of 0.148). The estimated coancestry coefficient within families (Θ = 0.147) was larger and the effective population size (Ne(v)) was lower (Ne(v) = 2.98) than expected in progenies from panmictic populations (Θ = 0.125, Ne(v) = 4, respectively). In terms of conservation, the results indicate that to retain an effective population size of 150, is necessary to collect seeds from at least 50 seed-trees.

Mating system parameters in a high density population of andirobas in the Amazon forest

The objective of this work was to estimate the mating system parameters of a andiroba (Carapa guianensis) population using microsatellite markers and the mixed and correlated mating models. Twelve open‑pollinated progeny arrays of 15 individuals were sampled in an area with C. guianensis estimated density of 25.7 trees per hectare. Overall, the species has a mixed reproductive system, with a predominance of outcrossing. The multilocus outcrossing rate (t m = 0.862) was significantly lower than the unity, indicating that self‑pollination occurred. The rate of biparental inbreeding was substantial (t m ‑ t s = 0.134) and significantly different from zero. The correlation of selfing within progenies was high (r s = 0.635), indicating variation in the individual outcrossing rate. Consistent with this result, the estimate of the individual outcrossing rate ranged from 0.598 to 0.978. The multilocus correlation of paternity was low (r p(m) = 0.081), but significantly different from zero, suggesting that the progenies contain full‑sibs. The coancestry within progenies (Θ = 0.185) was higher and the variance effective size (Ne(v) = 2.7) was lower than expected for true half‑sib progenies (Θ = 0.125; Ne(v) = 4). These results suggest that, in order to maintain a minimum effective size of 150 individuals for breeding, genetic conservation, and environmental reforestation programs, seeds from at least 56 trees must be collected.

The population of Brazil

In 1970 the population of Brazil with 94,508,554 inhabitants was extreme youth, since 42.67% was composed of children under 14 years old. In that year the proportion of female was 50.2%. The population density increased from 1.17 inhabitants /km² in 1872 to 11.18 in 1970, and in this last year the range was 1.03 in the North region and 43.90 in the South-East region. The urban population increased from 31.24% in 1940 to 55.98% in 1970 and for the first time the rural population was smaller than the urban population. In 1950 concerning with marital status 39% of the population 15 years old and over was single and 54% married. In 1970 this rate was respectively 35.4% and 56.6%. The population economically inactive increased from 49.17% in 1940 to 52.24% in 1970. The literacy ratio increased from 43% in 1940, to 48% in 1950 and 68.04% in 1970. The crude birth rate was 43/1000 live births in 1950 and fell to 37.7/1000 in 1970. The fertility rate decreased from 179.3/1000 women (15-49 years old} to 156.7/1000 in 1960/70. The crude death rate decreased from 20.60/1000 inhabitants in 1940/50 to 9.4/1000 in 1960/70. The infant mortality rate still remains high: 171/1000 live births in 1940/50 and 170/1000 in 1971. Concerning with the size of the cities, 8 in 1940 had 100,000 or more inhabitants and in 1970 this number increased to 94 cities. The population growth increased from 2.38% in 1940/50, to 2.99% in 1950/60 and 2.83% in 1960./70. Brazil is the first country in population size in Latin America and the eighth in the world. Concerning his area, Brazil is the fifth country in size.

Evaluation of dog population in an urban area of Southeastern Brazil

Planning control programs, for diseases such as rabies requires information on the size and structure of the dog and cat population. In order to evaluate the dog population of the urban area of Araçatuba city, S. Paulo State, Brazil, a survey was conducted using a questionnaire to interview members of households. Eighty-eight districts were visited (37,778 houses) and the interview was possible at 77.93% of these. Human population size evaluated was 113,157 inhabitants. Houses that owned animals represented 55.2%, 26,926 of the animals concerned were dogs and 5,755 were cats. Of the dogs, 56.64% were 1-4 year olds and males represented 56.2% of the total population. Dog: person ratio was estimated at 2.8 dogs to every 10 persons, almost 3 times the ratio hitherto estimated and used in the planning of rabies vaccination campaigns.

The resumption of consumption: a review on tuberculosis

Among all infectious diseases that afflict humans, tuberculosis (TB) remains the deadliest. At present, epidemiologists estimate that one-third of the world population is infected with tubercle bacilli, which is responsible for 8 to 10 million new cases of TB and 3 million deaths annually throughout the world. Approximately 95% of new cases and 98% of deaths occur in developing nations, generally due to the few resources available to ensure proper treatment and where human immunodeficiency virus (HIV) infections are common. In 1882, Dr Robert Koch identified an acid-fast bacterium, Mycobacterium tuberculosis, as the causative agent of TB. Thirty-nine years later, BCG vaccine was introduced for human use, and became the most widely used prophylactic strategy to fight TB in the world. The discovery of the properties of first-line antimycobacterial drugs in the past century yielded effective chemotherapies, which considerably decreased TB mortality rates worldwide. The later introduction of some additional drugs to the arsenal used to treat TB seemed to provide an adequate number of effective antimicrobial agents. The modern, standard short-course therapy for TB recommended by the World Health Organization is based on a four-drug regimen that must be strictly followed to prevent drug resistance acquisition, and relies on direct observation of patient compliance to ensure effective treatment. Mycobacteria show a high degree of intrinsic resistance to most antibiotics and chemotherapeutic agents due to the low permeability of its cell wall. Nevertheless, the cell wall barrier alone cannot produce significant levels of drug resistance. M. tuberculosis mutants resistant to any single drug are naturally present in any large bacterial population, irrespective of exposure to drugs. The frequency of mutants resistant to rifampicin and isoniazid, the two principal antimycobacterial drugs currently in use, is relatively high and, therefore, the large extra-cellular population of actively metabolizing and rapidly growing tubercle bacilli in cavitary lesions will contain organisms which are resistant to a single drug. Consequently, monotherapy or improperly administered two-drug therapies will select for drug-resistant mutants that may lead to drug resistance in the entire bacterial population. Thereby, despite the availability of effective chemotherapy and the moderately protective vaccine, new anti-TB agents are urgently needed to decrease the global incidence of TB. The resumption of TB, mainly caused by the emergence of multidrug-resistant (MDR) and extensively drug-resistant (XDR) strains and HIV epidemics, led to an increased need to understand the molecular mechanisms of drug action and drug resistance, which should provide significant insight into the development of newer compounds. The latter should be effective to combat both drug-susceptible and MDR/XDR-TB.

Cannibalism studies on eggs and newly hatched caterpillars in a wild population of Ascia monuste (Godart) (Lepidoptera, Pieridae)

Ascia monuste (Godart), also known as cabbage caterpillar, is considered herbivorous and specialist in Brassicaceae; however, it performs cannibalism. Experiments carried out in this work aimed to quantify the cannibalism occurrence in A. monuste, to verify whether cannibalism interferes in the species performance and to check whether cannibalism is influenced by the population size. The parameters used in order to evaluate the performance were time of development, adults weight and size, fecundity, oviposition and survival rate. Cannibalism occurred in all larval instars. There was a tendency to increase the cannibalism practice as the number of co-specific increased (potential preys). Cannibalism was more intense in larvae at the end of larval development. Generally, cannibalism did not interfere in the population performance. The most probable hypothesis for the occurrence of cannibalism in the conditions here studied would be the hypothesis of cannibalism as having the function of population control.

Integrated Management of Childhood Illness: efficiency of primary health in Northeast Brazil

OBJECTIVE: The Integrated Management of Childhood Illness is a strategy designed to address major causes of child mortality. The aim of this study was to assess the impact of the strategy on the quality of child health care provided at primary facilities. METHODS: Child health quality of care and costs were compared in four states in Northeastern Brazil, in 2001. There were studied 48 health facilities considered to have had stable strategy implementation at least two years before the start of study, with 48 matched comparison facilities in the same states. A single measure of correct management of sick children was used to assess care provided to all sick children. Costs included all resources at the national, state, local and facility levels associated with child health care. RESULTS: Facilities providing strategy-based care had significantly better management of sick children at no additional cost to municipalities relative to the comparison municipalities. At strategy facilities 72% of children were correctly managed compared with 56% in comparison facilities (p=0.001). The cost per child managed correctly was US$13.20 versus US$21.05 in the strategy and comparison municipalities, respectively, after standardization for population size. CONCLUSIONS: The strategy improves the efficiency of primary facilities in Northeastern Brazil. It leads to better health outcomes at no extra cost.

The occurrence of the Asian Clam Corbicula fluminea in the lowe amazon basin

This paper records for the first time the presence of Corbicula fluminea (Philipi, 1844) in the Brazilian Amazon Basin. This exotic bivalve was found in localities on the Amazonas, Pará and Tocantins rivers. Density and population size structure were measured in some localities. Mean density is between 6.66 and 7.3 individuals m-2. Population size structure and the dates of the first records suggest that the introductions may have occurred between 1997 and 1998. The introductions may have been mediated by ocean-going vessels visiting the ports of Manaus and Belém. The potential impact of the invasion on native freshwater bivalves is discussed along with the need for monitoring and prevention of further introductions of non-indigenous bivalves in Brazil.

Reticulo-endotheliomatose maligna

A spindle-cell sarcoma (fig. 5) apparently originating from the dura (fig. 4) was found at the autopsy of a male, mulato, 17 years of age. The bones of the skull (occipital and both parietals) were penetrated and destroyed (fig. 1 and 2). The nervous tissue was not penetrated, the only change in the brain being a depressed area where the tumor was included. Metastatic nodules were found in the liver (fig. 3),hepatic lymphnodes (fig. 14), spleen (fig. 12) and suprarenal bodies (fig. 15). The structure, however, in all those different locations was that of a typical endothelioma (figs. 8, 11 and 13). The cells are of large and moderate size, of polyhedral form, with vesicular nuclei, diminutive nucleoli and clear cytoplasm. (Figs. 6 and 8). They are arranged about a central lumen which represents a rudimentary vessel (figs. 9 and 13). Other areas are composed of cells without concentric arrangement (figs. 4 and 10). In small areas, the colums of liver cells are marginated in one side by typical sinusoids, while in the other side tumor cells arranged about a narrow lumen are seen suggesting a pathological (neoplastic) sinusoid (figs. 7 and 9). The case is considered as a multiple diffuse endothelioma. The origin of the tumor is referred to the reticulo-endothelial apparatus of the liver, the spleen, the suprarenal bodies and the lymph nodes, the structure being rather uniform in those organs. In the dura, the endothelioma reproduces the structure and presents the general character of a fibroblastic sarcoma; in some places, however, the structure of endothelioma could be found (fig.6). It corresponds to the reticulo-endotheliomatosis maligna according to Puhr's grouping of progressive changes in the reticulo-endothelial apparatus which is a follows: 1. HYPERPLASTIC - 1. Mnnocytic leukemia. 2. a) Aleukemic reticulosis (Goldschmid and Isaac). b) Idiopathic sarcoma of skin (Kaposi). c) Cutaneous sarcoid (Spiegler). 3. Secretory reticulosis. a) Gaucher's disease. b) Generalized xanthomatosis. c) Spleno-hepatomegaly with lipoidic cells (Pick). II. BLASTOMATOSUS OR NEOPLASTIC - 1. Benign - a) Circumscribed tumors. a) Epulis sarcomatosa; b) Benign giant-cells sarcoma of the bone - marrow of long bones. b) Generalized brown tumors of osteitis fibrosa. 2. Malignant - a) Circumscribed haemangio - endothelioma (reticulo- endothelioma (maligum). of {liver, spleen, bone-marrow. b) Generalized haemangio-endotheliomatosis (reticulo-endotheliomatosis maligna) (Grabowski).