High performance free-standing films by layer-by-layer assembly of graphene flakes and ribbons with natural polymers.

In this work, novel free-standing (FS) films based on chitosan, alginate and graphene oxide (GO) were developed through layer-by-layer assembly. First, GO was synthesized from graphite and multi-walled carbon nanotubes using a modified Hummer's method, yielding oxidized graphene flakes (o-GFs) and oxidized graphene nanoribbons (o-GNRs), respectively, which were then characterized. Then FS films were produced and their morphological, thermal and mechanical properties, as well as the o-GF and o-GNR dispersion along the films were assessed. Their degradation and swelling profiles as well as their biological behavior were evaluated. Graphite and nanotubes were successfully oxidized and exfoliated forming stable suspensions that could be combined with chitosan (CHI) and alginate (ALG) solutions by layer-by-layer processing. The addition of o-GFs and o-GNRs resulted in rougher, hydrophilic FS films with significantly improved mechanical properties relative to CHI/ALG films. The presence of o-GFs or o-GNRs did not affect the thermal stability and the addition of o-GFs resulted in films with enhanced cytocompatibility. The results demonstrate the high potential of the GO reinforced films for biomedical applications, in particular o-GF films, for wound healing, and cardiac and bone engineering applications.

Crescimento, produção de fitomassa e teor de óleo essencial de folhas de capim citronela (Cymbopogon nardus (L. ) Rendle) em cultivo consorciado com algodoeiro colorido no semiárido mineiro / Growth, phytomass yield and essential oil content of leaves of citronella grass [Cymbopogon nardus (L. ) Rendle] intercropping with colored cotton

Avaliou-se o crescimento, a produção e o teor do óleo essencial de dois cortes de capim citronela em cultivo consorciado com algodoeiro colorido no semiárido. Para isso foram utilizados dois sistemas de consórcios (tratamentos): algodão colorido consorciado com capim citronela 3x1 e algodão colorido consorciado com capim citronela 1x1. A variedade de algodão colorido utilizada foi a BRS Rubi e as mudas de capim citronela foram produzidas no Horto de Plantas Medicinais da Unimontes. O delineamento experimental utilizado foi em blocos casualizados com dois tratamentos e 16 repetições. O experimento foi mantido em regime de sequeiro e foi avaliado a altura das plantas de capim citronela. Foram realizadas duas colheitas das folhas de capim citronela, sendo a primeira no momento da colheita da fibra do algodão e a segunda na rebrota do capim, seis meses após. Todas as plantas da parcela foram colhidas e as folhas frescas foram pesadas, no campo, com o auxílio de balança digital. Amostras das folhas colhidas foram retiradas e levadas para secagem em estufa com circulação forçada de ar a 35ºC até atingirem massa constante. Foi verificada a massa seca e posteriormente realizada a extração do óleo essencial pelo método de hidrodestilação em aparelho modificado de Clevenger. Os dados foram submetidos à análise de variância e as médias comparadas pelo teste Skott-Knott (p<0,05). A altura das plantas não diferiu entre os tratamentos nas colheitas. Para a produção de massa fresca e seca houve diferença entre os tratamentos apenas na segunda colheita. Neste caso, as plantas cultivadas em consórcio 1x1 produziram mais do que as do consórcio 3x1. O teor de óleo essencial de capim citronela não variou entre os dois sistemas de consórcio, tanto no primeiro como no segundo corte.

The research was performed to evaluate the growth, production and essential oil content of the two harvests of citronella grass in intercropped with colored cotton in semiarid.For this, was used two system consortium (treatments): colored cotton intercropped with citronella grass 3X1 and colored cotton intercropped with citronella grass 1X1. The variety of colored cotton used was BRS Rubi and the citronella grass seedlings were produced in the Medicinal Plants Garden of Unimontes. The experimental design used was randomized blocks with two treatments and 16 repetitions. The experiment was maintained under rainfed conditions. Was evaluated plant height of citronella grass. Citronella grass leaves were harvested twice: the first was made at harvest of cotton fiber and the second in the grass regrowth, six months later. All plants in the plot were harvested and the fresh leaves were weighed, in the field, with the aid of a digital balance. Samples from leaves harvested were collected and taken for drying in an oven with forced air at 35ºC until reaching constant weight. Dry mass was verified and the performed the extraction of essential oil by hydrodestilation in Clevenger modified apparatus. Data were subjected to analysis of variance and means compared by Skott-Knott test (p<0.05). The plants height did not differ between treatments in harvests. For the production of fresh and dry mass was significant difference between treatments only in the second harvest. In this case the plants cultivated in the consortium 1x1 produced more than in the consortium 3x1. The essential oil content of citronella grass did not vary between the two systems consortium, in the first and the second harvest.

Attractiveness of black Shannon trap for phlebotomines.

A white Shannon-type trap was used for captures of female sand flies in the search for natural infection with flagellates, however, due to its low productivity and as a large number of phlebotomines settled on the researchers' black clothes, we decided to compare the relative attractiveness of black and white Shannon-type traps for sand flies. Several pairs of black and white traps were placed side by side in front of caves in four areas in the Serra da Bodoquena, Bonito county, State of Mato Grosso do Sul, Brazil, for a total of 12 observations and 44 h of capture. The experiment resulted in 889 phlebotomines captured, 801 on the black and 88 on the white trap, representing 13 species. The hourly Williams' means were 8.67 and 1.24, respectively, and the black/white ratio was 7.0:1.0. Lutzomyia almerioi, an anthropophilic species closely associated with caves, was predominant (89%). Only two other species, Nyssomyia whitmani and Psathyromyia punctigeniculata, also anthropophilic, were significantly attracted to the black rather than to the white trap (chi(2) test; p < or = 0.01). The difference between the diversity index of the two traps was not significant at level 0.05. The black trap in these circumstances was much more productive than the white, especially for anthropophilic species.

[Occurrence of canine visceral leishmaniasis in an agricultural settlement in the State of Mato Grosso do Sul, Brazil]. / Ocorrência de leishmaniose visceral canina em assentamento agrícola no Estado de Mato Grosso do Sul, Brasil.

During previous research on phlebotomine fauna in a settlement of the Brazilian National Agrarian Reform Institute (INCRA) on the Bodoquena Range, Mato Grosso do Sul State, Brazil, dogs were observed with clinical aspects suggestive of visceral leishmaniasis. A serological survey to leishmaniasis in 97 dogs, by indirect immunofluorescence test, showed 23 (23.7%) serum positive dogs. Samples of the parasites were identified as Leishmania (Leishmania) chagasi.

Attractiveness of black Shannon trap for phlebotomines

A white Shannon-type trap was used for captures of female sand flies in the search for natural infection with flagellates, however, due to its low productivity and as a large number of phlebotomines settled on the researchers' black clothes, we decided to compare the relative attractiveness of black and white Shannon-type traps for sand flies. Several pairs of black and white traps were placed side by side in front of caves in four areas in the Serra da Bodoquena, Bonito county, State of Mato Grosso do Sul, Brazil, for a total of 12 observations and 44 h of capture. The experiment resulted in 889 phlebotomines captured, 801 on the black and 88 on the white trap, representing 13 species. The hourly Williams' means were 8.67 and 1.24, respectively, and the black/white ratio was 7.0:1.0. Lutzomyia almerioi, an anthropophilic species closely associated with caves, was predominant (89 percent). Only two other species, Nyssomyia whitmani and Psathyromyia punctigeniculata, also anthropophilic, were significantly attracted to the black rather than to the white trap (chi2 test; p <= 0.01). The difference between the diversity index of the two traps was not significant at level 0.05. The black trap in these circumstances was much more productive than the white, especially for anthropophilic species

Ocorrência de leishmaniose visceral canina em assentamento agrícola no Estado de Mato Grosso do Sul, Brasil / Occurrence of canine visceral leishmaniasis in an agricultural settlement in the State of Mato Grosso do Sul, Brazil

During previous research on phlebotomine fauna in a settlement of the Brazilian National Agrarian Reform Institute (INCRA) on the Bodoquena Range, Mato Grosso do Sul State, Brazil, dogs were observed with clinical aspects suggestive of visceral leishmaniasis. A serological survey to leishmaniasis in 97 dogs, by indirect immunofluorescence test, showed 23 (23.7%) serum positive dogs. Samples of the parasites were identified as Leishmania (Leishmania) chagasi.

Durante estudos sobre a fauna flebotomínea em assentamento do Instituto Nacional de Reforma Agrária (INCRA) na Serra da Bodoquena, Estado de Mato Grosso do Sul, Brasil, foram observados cães com manifestações clínicas sugestivas de leishmaniose visceral. Inquérito sorológico para leishmaniose em 97 cães, utilizando reação de imunofluorescência indireta, mostrou 23 (23,7%) soros reagentes. Amostras do parasita foram identificadas como Leishmania (Leishmania) chagasi.

Venom production by africanized honeybees (Apis mellifera) and africanized-european hybrids

This study used 15 beehives: five with Africanized queens sisters (Apis mellifera), five with Italian queens sisters (Apis mellifera ligustica), and five with Carniolan queens sisters (Apis meliifera carnica). The queens were fertilized naturally. This experiment was performed in the apiary of the Botucatu School of Veterinary Medicine and Animal Husbandry, UNESP, State of Säo Paulo, Brazil. The following data were obtained from the foraging bees: venom quantity in reservoir, 0.117ñ0.015, 0.139ñ0.020, and 0.147ñ0.024 (mg); venom quantity liberated in extraction apparatus, 0.073ñ0.012, 0.057ñ0.011 and 0.059ñ0.013 (mg); and sting electro stimulus threshold (volts), 10.75ñ1.37, 15.11ñ2.00, and 15.01ñ1.63 for Africanized, Italian x Africanized and Carniolan x Africanized, respectively. The Africanized honeybees possess less venom in reservoir than the European hybrids (Carniolan and Italian). However, they liberated a larger quantity of venom in the extraction apparatus and required lower electro stimulus threshold to promote stinging.

[Study of the phlebotomines (Diptera, Psychodidae), in area of cutaneous leishmaniasis in the State of Mato Grosso do Sul, Brazil]. / Estudo dos flebotomíneos (Diptera, Pychodidae), em área de leishmaniose tegumentar, no Estado de Mato Grosso do Sul, Brasil.

Studies of the phlebotomine sandflies on the Boa Sorte farm, Corguinho country, State of Mato Grosso do Sul, Central-West region of Brazil, were carried out, with the object of identifying local fauna and a cutaneous leishmaniasis vector. At the beginning of the studies, several types of primitive vegetation covering: gallery forest, forest slopes and the cerrados: s. str. and tropical xeromorphic semideciduous broadleaf forest, locally denominated "croa", existed. Four months after the beginning of the studies, a fire destroyed a significant part of the cerrados. Captures were made during the interval from July/91 to June/93, with a CDC trap, weekly, at 10 ecotopes: in the soil of forest slopes; in the soil and canopy of cerrado s. str., "croa" and gallery forest; in the peridomicile, in hen house and pigpen and in a storage shed. A Shannon's trap was used, monthly, from 18:00-24:00 hours, in the gallery forest and "croa". Human bait was used, monthly, for 24 hours, from June/91 to September/92. An investigation into natural infection in female phlebotomines was made through the dissection of specimens captured in the Shannon's trap and on human bait. The captures with CDC totalled in 2,281 specimens of 26 species: 2 of Brumptomyia and 24 of Lutzomyia. The "croa" was the environment that contributed with the greatest number of specimens and presented the largest diversity, together with the forest slope. L, withmani was the most abundant species captured with CDC, in all the ecotopes (Standardized abundance index = 0.991). However, in the storage shed its frequency was the lowest. This species presented a prevalence of 96.0% in the Shannon's trap and on human bait (3,265 and 516 specimens, respectively). It was the most frequent in the cold and dry periods. It presented almost exclusively nocturnal activity, with its peak at 18:00-19:00 hours and an infection rate by flagellates of 0.16% (613 females dissected). On the basis of its behavior, this species was incriminated as the probable vector of the cutaneous leishmaniasis in the area, which had extradomicilary transmission. L. lenti, the second most abundant species, is not anthropophilic. The phlebotomine fauna is presented by environment.

[Epidemiologic study on tegumentary leishmaniasis in the municipality of Corguinho, Mato Grosso do Sul -- Studies in the human population]. / Estudo epidemiológico sobre leishmaniose tegumentar (LT) no município de Corguinho, Mato Grosso do Sul-Estudos na população humana.

A study on the resident population of 150 inhabitants of Boa Sorte in the Municipality of Corguinho, Mato Grosso do Sul State, Brazil was made, from March 1991 to March 1994, to establish the prevalence of South American Cutaneous Leishmaniasis (SACL), and to characterize the affected population, in an area of recent transmission. Twelve of the inhabitants showed lesions suspected to be SACL, and in 8 cases it was possible to confirm this by biopsy and parasitology. The mucosal form was found in one patient only, the rest showed the following cutaneous forms: ulcerated (3), ulcero-verrucose (1), hyperkeratotic ulcer (1), infiltrated maccule (1), nodule with florid regional adenopathy (1). All patients reacted favorably to treatment with glucantime, with lesion scarring. Side-effects were rare. The parasite isolated from all patients was identified as Leishmania (Viannia) braziliensis. The Montenegro skin test, applied to the 150 inhabitants, showed 32 reactive ones. Of these, six were carriers of the disease, 21 showed sequelae suggestive of the disease and five showed no signs of infection. The age grouping of the cohort ranged from 22 to 78 years, 75% being male. To date, transmission is suspected to be in the peridomicile.