Sugarcane productivity correlated with physical-chemical attributes to create soil management zone

The socioeconomic importance of sugar cane in Brazil is unquestionable because it is the raw material for the production of ethanol and sugar. The accurate spatial intervention in the management of the crop, resulting zones of soil management, increases productivity as well as its agricultural yields. The spatial and Person's correlations between sugarcane attributes and physico-chemical attributes of a Typic Tropustalf were studied in the growing season of 2009, in Suzanápolis, State of São Paulo, Brazil (20°28'10'' S lat.; 50°49'20'' W long.), in order to obtain the one that best correlates with agricultural productivity. Thus, the geostatistical grid with 120 sampling points was installed to soil and data collection in a plot of 14.6 ha with second crop sugarcane. Due to their substantial and excellent linear and spatial correlations with the productivity of the sugarcane, the population of plants and the organic matter content of the soil, by evidencing substantial correlations, linear and spatial, with the productivity of sugarcane, were indicators of management zones strongly attached to such productivity.

Vector competence experiments with Rocio virus and three mosquito species from the epidemic zone in Brazil

First-generation progeny of field-collected Psorophora ferox, Aedes scapularis, and Aedes serratus from the Rocio encephalitis epidemic zone in S.Paulo State, Brazil, were tested for vector competency in the laboratory. Psorophora ferox and Ae. scapularis are susceptible to per os infection with Rocio virus and can transmit the virus by bite following a suitable incubation period. Oral ID50S for the two species (10(4.1) and 10(4.3) Vero cell plaque forming units, respectively) did not differ significantly. Infection rates in Ae. serratus never exceeded 36%, and, consequently, an ID50 could not be calculated for this species. It is unlikely that Ae. serratus is an epidemiologically important vector of Rocio virus. The utility of an in vitro feeding technique for demonstrating virus transmission by infected mosquitoes and difficulties encountered in working with uncolonized progeny of field-collected mosquitoes are discussed.

Finding Aedes aegypti in a natural breeding site in an urban zone, Sao Paulo, Southeastern Brazil

ABSTRACT This is the description of how nine Aedes aegypti larvae were found in a natural breeding site in the Pinheiros neighborhood, city of Sao Paulo, SP, Southeastern Brazil. The record was conducted in December 2014, during an entomological surveillance program of dengue virus vectors, with an active search of potential breeding sites, either artificial or natural. Finding Ae. aegypti larvae in a tree hole shows this species’ ability to use both artificial and natural environments as breeding sites and habitats, which points towards the importance of maintaining continuous surveillance on this mosquito in all kinds of water-holding containers.

Immunization aganist hepatitis B in children from endemic zone: evaluation of the antibody response against the DNA recombinant vaccine (Engerix B-20 mcg)

A previous seroepidemiological study in the rural zone of Vargem Alta (ES) SouthEast of Brazil, showed a prevalence of up to 9% of hepatitis B surface antigen (HBsAg) in some areas. One hundred susceptible children aging 1 to 5 years old were selected and immunized with a recombinant DNA hepatitis B vaccine (Smith-Kline 20 mcg) using the 0-1-6 months vaccination schedule. Blood samples were collected at the time of the first vaccine dose (month 0) in order to confirm susceptible individuals and 1,3,6 and 8 months after the first dose , to evaluate the antibody response. Our results showed that two and five months after the second dose, 79% and 88% of children seroconverted respectively, reaching 97% after the third dose. The levels of anti-HBs were calculated in milli International Units/ml (mIU/ml) and demonstrated the markedly increase of protective levels of antibodies after the third dose. These data showed a good immunogenicity of the DNA recombinant hepatitis B vaccine when administered in children of endemic areas.

Effects of tissue handling and processing steps on PCR for detection of Mycobacterium tuberculosis in formalin-fixed paraffin-embedded samples

Development and standardization of reliable methods for detection of Mycobacterium tuberculosis in clinical samples is an important goal in laboratories throughout the world. In this work, lung and spleen fragments from a patient who died with the diagnosis of miliary tuberculosis were used to evaluate the influence of the type of fixative as well as the fixation and paraffin inclusion protocols on PCR performance in paraffin embedded specimens. Tissue fragments were fixed for four h to 48 h, using either 10% non-buffered or 10% buffered formalin, and embedded in pure paraffin or paraffin mixed with bee wax. Specimens were submitted to PCR for amplification of the human beta-actin gene and separately for amplification of the insertion sequence IS6110, specific from the M. tuberculosis complex. Amplification of the beta-actin gene was positive in all samples. No amplicons were generated by PCR-IS6110 when lung tissue fragments were fixed using 10% non-buffered formalin and were embedded in paraffin containing bee wax. In conclusion, combined inhibitory factors interfere in the detection of M. tuberculosis in stored material. It is important to control these inhibitory factors in order to implement molecular diagnosis in pathology laboratories.

BIOFILM FORMATION OF Vibrio cholerae ON STAINLESS STEEL USED IN FOOD PROCESSING

Vibrio cholerae represents a significant threat to human health in developing countries. This pathogen forms biofilms which favors its attachment to surfaces and its survival and transmission by water or food. This work evaluated the in vitro biofilm formation of V. cholerae isolated from clinical and environmental sources on stainless steel of the type used in food processing by using the environmental scanning electron microscopy (ESEM). Results showed no cell adhesion at 4 h and scarce surface colonization at 24 h. Biofilms from the environmental strain were observed at 48 h with high cellular aggregations embedded in Vibrio exopolysaccharide (VPS), while less confluence and VPS production with microcolonies of elongated cells were observed in biofilms produced by the clinical strain. At 96 h the biofilms of the environmental strain were released from the surface leaving coccoid cells and residual structures, whereas biofilms of the clinical strain formed highly organized structures such as channels, mushroom-like and pillars. This is the first study that has shown the in vitro ability of V. cholerae to colonize and form biofilms on stainless steel used in food processing.

Epidemiologic studies of chagas' disease in the urban zone of Teresina. State of Piauí, northeastern Brazil

The triatomine species Rhodnius nasutus and Triatoma pseudomaculata were captured on palm trees Orbignya martiana "babaçu ", in the urban zone of Teresina. This kind of palm tree is largely distributed in Piauí State. The predominant species was R. nasutus; the young in stars predominated. The infestation index of palm trees and the infection index of triatomines by flagellates were 96.0 ana 29.1%, respectively. Marsupiais, bats and a rodent were captured in palm trees. The flagellates found in both triatomines ana marsupiais were morphologically and biologically indistinguishable from Trypanosoma cruzi. Forty seven percent (481/1,025) of triatomines were found concentrated in six palm trees where marsupiais circulated. Of the total of 1,025 triatomines 230 (22%) were infected by flagellates and 53.0% (123/230) of these infected triatomines were present in the same six palm trees. No evidence of triatomine domiciliation or human transmission was observed in the houses in the vicinity of palm trees. The results suggest that marsupiais play an important role in the life-cycle of T. cruzi in this region. The natural focus of Chagas' disease, demonstrated in the present study could represent a potential epidemiological threat.

Presence of anti-Toxoplasma antibodies in humans and their cats in the urban zone of Guadalajara

Cats are the definitive hosts of Toxoplasma gondii. Infected cats excrete oocysts in their feces, infecting humans and other animals. The objective of the present study was to determine the presence of anti-Toxoplasma antibodies in cat owners and their pets, and determine if there was a relationship between Toxoplasma infection and humans who live with infected cats. IgG anti-Toxoplasma antibodies in sera of 59 cat owners were determined by enzyme-linked immunosorbent assay (ELISA), in 24 sera from their cats, IgG, IgM, and IgA antibodies were found using Burney's ELISA. Thirty-eight (64%) of 59 cat owners were positive to IgG anti-Toxoplasma. Seropositivity for cats was 70.8% IgG, 8.3% IgM, and 62.5% IgA. Cohabitation with cats infected by T. gondii, feeding with leftovers or raw viscera, and lack of control over how their feces were handled are risk factors conducive for humans to become infected by T. gondii.

First record on Loxosceles laeta (Nicolet, 1849) (Araneae, Sicariidae) in the West Zone of São Paulo City, São Paulo, Brazil, and considerations regarding its geographic distribution

Loxosceles laeta spiders were captured in the West zone of São Paulo City, this being the first record of the specie in this area. Since loxoscelism is an important public health problem in the South region of Brazil, it is necessary to investigate the presence of this spider in São Paulo City.

Seroepidemiology of Trypanosoma cruzi infection in the semiarid rural zone of the State of Rio Grande do Norte, Brazil

INTRODUCTION: A seroepidemiological survey was carried out to evaluate Trypanosoma cruzi infection in an endemic area of the State of Rio Grande do Norte, Brazil, involving rural residents. METHODS: Sixteen municipalities were randomly selected, 15 from the west mesoregion and one from the central, with an estimated population of 83,852 individuals. A total of 1,950 blood samples were collected in the west mesoregion and 390 in Caicó. Anti-T. cruzi antibodies were detected using the Chagatest® ELISA HAI-hemagglutination kits and indirect immunofluorescence. As sera presented indeterminate results, TESAcruzi® western blot was performed to confirm reactivity. RESULTS: An estimated seroprevalence of 6.5% was determined for the west mesoregion and 3.3% for Caicó. Seropositivity rises progressively with the age of individuals, up to 40 years in Caicó and up to 50 years in the west mesoregion. Only educational level and knowledge regarding the triatomine were associated with seropositivity. No seroreactive individuals under 18 years of age were identified. CONCLUSIONS: Infection by T. cruzi remains high and is concentrated in municipalities in the central western area of the west mesoregion; however, evidence suggests a decline in vector transmission in this mesoregion and in Caicó. Epidemiological variables appear not to influence seropositivity, with the exception of education and knowledge concerning the triatomine, among seroreactive individuals from the west mesoregion.

Planktonic ciliates Choreotrichida and Strombidiida from the inner zone of Bahía Blanca Estuary, Argentina

Seven species of aloricate planktonic ciliates were identified using protargol staining. Choreotrichida: Strombidinopsidae, Strombidinopsis elongata Song & Bradbury, 1998; Strobiliidae, Strobilidium epacrum Lynn & Montagnes, 1988 and Strombidiida: Strombidiidae, Strombidium capitatum (Leegaard, 1915) Kahl, 1932; S. emergens (Leegaard, 1915) Kahl, 1932; S. acutum Leegaard, 1915; S. dalum Lynn, Montagnes & Small, 1988 and Cyrtostrombidium longisomum Lynn & Gilron, 1993; they were collected from the inner zone of the Bahía Blanca estuary in the southern region of the Buenos Aires province, Argentina. These species represent new records to South America (Argentina).

Abundance and species composition of planktonic Ciliophora from the wastewater discharge zone in the Bahía Blanca Estuary, Argentina

The specific composition and abundance variation of the ciliate community from a wastewater discharge zone in the Bahía Blanca estuary, Argentina, were studied all throughout a year, from June 1995 to May 1996. The polluted area exhibited high values of particulate organic matter and nutrients, particularly phosphates. Aloricate ciliates were represented by 15 species belonging to the genera Strombidium Claparède & Lachmann, 1859; Strombidinopsis Kent, 1881; Cyrtostrombidium Lynn & Gilron, 1993; Strobilidium Schewiakoff, 1983; Lohmmanniella Leegaard, 1915 and Tontonia Fauré-Fremiet, 1914. Tintinnids were represented by nine species belonging to the genera Tintinnidium Kent, 1881, Tintinnopsis Stein, 1867 and Codonellopsis Jörgensen, 1924. The total abundance of aloricate ciliates reached a peak of 1,800 ind. 1-1 and the total abundance of tintinnids reached a peak of 9,400 ind. 1-1. Tintinnidium balechi Barría de Cao, 1981 was the most abundant ciliate in the community. Considerations on the presence and abundance of ciliates are made in relation to physicochemical and biochemical parameters.

Hydroids (Cnidaria, Hydrozoa) of the intertidal zone of Governador and Paquetá islands, Guanabara Bay, Rio de Janeiro, Brazil

During six consecutive months, sampling were made at three points located on Governador Island and three on Paquetá Island in Guanabara Bay, Rio de Janeiro, Brazil. Material was collected from dock pilings and rocks in the intertidal zone. In these samples, five species belonging to three families, Corynidae, Kirchenpaueriidae and Campanulariidae, were identified. The campanulariid species Obelia dichotoma Linnaeus, 1758, dominated at nearly all points sampled. The small number of species obtained in this survey is attributed to the intense pollution in the bay, which borders the second-largest industrial complex and the second-largest demographic center of Brazil.

Mollusks: how are they arranged in the rocky intertidal zone?

Mollusks occupy different kinds of environments, including the intertidal zone. The present study investigated the spatial distribution of mollusks on beach rocks of the intertidal zone of Pacheco Beach in the state of Ceará, Brazil. Sampling occurred from August 2006 to September 2007. Across two transects, six samples of 0.25 m² were collected monthly in gaps of 30 m (0 m, 30 m, 60 m, 90 m, 120 m and 150 m). The mollusks were counted in field, and samples of sediment and algae were taken for further analysis. A total of 74,515 individuals were found and classified into 67 species, 52 genera and 39 families. Gastropods were predominant, corresponding to 73.1% of the species, followed by bivalves (22.4%) and chitons (4.5%). Caecum ryssotitum de Folin, 1867 was the most abundant taxon, representing 68.8% of total specimen findings. In general, species were mostly found in Middle Littoral zone (samples 60 m and 90 m), suggesting that the greater number of microenvironments available in this area may contribute to establishment and survival.

Hatching and larval export of the intertidal crab Neohelice granulata in Mar Chiquita coastal lagoon, Argentina

Synchronization in the events of the reproductive cycle in female Neohelice granulata Dana, 1851 were studied from samples taken weekly and biweekly from September to December 2006 in the Laguna Mar Chiquita. The timing and larval hatching and synchronicity were inferred from numbers of ovigerous females and observing the stages of embryonic development. Synchronization in larval hatching also was observed in females in experiments in dark for a period of 48 hours, at three different salinities (10, 23 and 33 ppm). In addition plankton sampling were performed in order to study larval exportation at the field and its link to the tidal and light/dark cycles. We found that ovigerous females of N. granulata have a marked synchronization in embryonic development which results in that most of berried females are close to hatching within a period of maximum tidal range (days). Within this period, there is a synchronization of hatching at a time scale of hours, governed by environmental conditions. The salinity range used in this study (10-32‰) did not affect hatching synchronicity neither time to hatch. Hatching was synchronized according to endogenous rhythms governed mainly by the tidal cycle and secondarily by the breadth of it. It is also conditioned by the light-dark cycle through an exogenous cycle, so that the hatchings would occur mostly at night high tides.