Mosquito species occurrence in association with landscape composition in green urban areas / Ocorrência de espécies de mosquitos associada à composição de paisagem em áreas verdes urbanas

Abstract Aedes aegypti prefers densely populated habitats, but has been shown to explore less anthropogenic environments. We investigated composition of the abundance of mosquitoes in forested areas and assessed relationships between species occurrences and different types of land use and land cover at three spatial scales (100m, 500m and 1000m). Mosquitoes were collected from October 2012 to March 2013 using oviposition traps. We collected 4,179 mosquitoes in total including at least 10 species. Aedes albopictus and Limatus durhami were eudominant species, representing 90% of all collected individuals. We found intraspecific differences in response to land use and land cover, and species response patterns were similar at all spatial scales. Ae. albopictus relative abundance was associated with urbanized areas, while Li. durhami, Haemagogus leucocelaenus and Toxorhynchites sp., abundances were associated with native forest. Aedes aegypti were found in five of the eight areas studied, including in an Atlantic forest fragment at a considerable distance from the forest edge (370 m). Aedes aegypti occurrence was not influenced by type of land use or land cover.

Resumo Aedes aegypti tem como habitat preferencial áreas densamente povoadas, mas que tem se mostrado capaz de explorar ambientes menos antropizados. O objetivo desse trabalho foi investigar a abundância de mosquitos em áreas florestadas e avaliar a relação dos diferentes tipos de uso e cobertura do solo, em três escalas de paisagem (buffer de 100m, 500m e 1000m). Os mosquitos foram coletados entre outubro de 2012 a março de 2013 utilizando armadilhas de oviposição. Foram coletados 4,179 culicídeos, de pelo menos 10 espécies, destas, Aedes albopictus e Limatus durhami foram eudominantes, representando 90% do total de indivíduos coletados. As espécies de culicídeos respondem de maneira diversa aos tipos de uso e cobertura do solo, indicando que as afinidades mais evidentes se mantém nas três escalas avaliadas. A abundância relativa de Ae. albopictus se mostrou relacionada às áreas mais urbanizadas, enquanto a de Li. durhami, Haemagogus leucocelaenus e Toxorhynchites sp., à presença da mata nativa. Aedes aegypti esteve presente em cinco das oito áreas estudadas, incluindo um fragmento de Mata Atlântica a uma distância considerável da borda (370m). A ocorrência de Aedes aegypti nas áreas analisadas não demonstrou ser influenciada pelo tipo de uso e cobertura do solo.

Mosquito species occurrence in association with landscape composition in green urban areas.

Aedes aegypti prefers densely populated habitats, but has been shown to explore less anthropogenic environments. We investigated composition of the abundance of mosquitoes in forested areas and assessed relationships between species occurrences and different types of land use and land cover at three spatial scales (100m, 500m and 1000m). Mosquitoes were collected from October 2012 to March 2013 using oviposition traps. We collected 4,179 mosquitoes in total including at least 10 species. Aedes albopictus and Limatus durhami were eudominant species, representing 90% of all collected individuals. We found intraspecific differences in response to land use and land cover, and species response patterns were similar at all spatial scales. Ae. albopictus relative abundance was associated with urbanized areas, while Li. durhami, Haemagogus leucocelaenus and Toxorhynchites sp., abundances were associated with native forest. Aedes aegypti were found in five of the eight areas studied, including in an Atlantic forest fragment at a considerable distance from the forest edge (370 m). Aedes aegypti occurrence was not influenced by type of land use or land cover.

The influence of glutathione modulators on the course of Leishmania major infection in susceptible and resistant mice.

Glutathione (GSH) has an important dual role in parasite-host relationship in Leishmania major infection. Our previous studies showed that both antioxidant systems, glutathione and trypanothione/trypanothione reductase, participate in the protection of Leishmania against the toxic effect of nitrogen-derived reactive species. On the other hand, GSH also is very important to the modulation of the effective immune response, inducting NO production and leishmanicidal activity of macrophages. In the present study, we investigated the role of host GSH during the course of L. major infection, analysing the size of footpad lesions and parasite load from mice treated with two GSH modulators, N-acethyl-l-cysteine (NAC) and buthionine sulphoximine (BSO). Resistant mice treated with BSO, which depletes GSH develop exacerbated lesions, but only harbour higher parasite load in their lesions 2 weeks post-infection. Although the NAC treatment does not affect the footpad lesions development in susceptible BALB/c mice, it significantly reduced the tissue parasitism in the lesions throughout the course of infection. Interestingly, the treatment with BSO did not change the course of L. major infection on susceptible mice when compared with nontreated mice. These results suggest that GSH is an important antioxidant modulator during anti-Leishmania immune response in vivo.

In vitro dissolution studies of sodium diclofenac granules coated with Eudragit L-30D-55 by fluidized-bed system.

The objective of this work was to study the dissolution process of sodium diclofenac granules coated with a polymeric suspension of Eudragit L-30D-55 by fluidized bed. Methacrylic acid-methylmetacrylate copolymer, also known as Eudragit, has been used as a pH sensitive coating material to protect drug substances prior to delivery to the human intestines. The sodium diclofenac granules were prepared by wet granulation technology using microcrystalline cellulose (MICROCEL), sodium diclofenac, and polivinilpirrolidone K-30. The granules coating operation was carried out in a fluidized bed with top spraying by a double-fluid nozzle. The dissolutions studies of the coated granules were performed in triplicate in a dissolution test station according to USP XXIII (1995) "in vitro testing requirements" Method A (paddle method, rotation of 100 RPM and temperature fixed at 37 degrees C). The dissolution mediums were 0.1N HCl solution and a pH 6.8 phosphate buffer solution, following the pH change dissolution procedure specified in USP for enteric-coated articles: 2 h of exposure to 750 mL of 0.1N HCl followed by testing in 1000 mL of pH 6.8 phosphate buffer, the pH being adjusted with 250 mL of 0.2 M tribasic sodium phosphate solution. The released amount of sodium diclofenac was periodically determined by UV spectrophotometry at wavelength of 276 nm, using a spectrophotometer UV-VIS HP 8453. The coated product showed gastric resistance properties confirming the feasibility of the fluidized bed for applying enteric coating in granules and pharmaceutical powders.

Comparative study of the mouthparts of males and females of Lutzomyia migonei (Diptera: Psychodidae) by scanning electron microscopy.

The mouthparts of both males and females of Lutzomyia migonei França were compared by scanning electron microscopy (SEM) and light microscopy (LM), and their structures are herein described. Mandibles are present in both sexes but in males they are reduced and, in contrast to females, no teeth were observed. As in females, the laciniae in males are highly sclerotized, but the number of lateral teeth are reduced and retrorse teeth are absent. Only females possess teeth at the tip of the hypopharynx, whereas in males they are substituted by spicula. Except for the length from the junction with the hypopharynx to the tip, which is shorter in males than in females, the labrum is similar in both sexes in terms of form and sensilla. On the labrum of males sensilla could be detected similar to the apical sensilla of females which play a role in the identification of blood.

Contribution to the sand fly fauna (Diptera: Phlebotominae) of Rio Grande do Sul, Brazil and Leishmania (Viannia) infections.

American cutaneous leishmaniasis (ACL) is endemic in the State of Rio Grande do Sul, Brazil. As reports of nearby hospitals suggest, the Parque Estadual do Turvo seems to serve as a source for the disease. During three months from November 1996 to February 1997 we collected, in this park, 2,228 sandflies (10 Lutzomyia species and 2 6species). We applied the polymerase chain reaction to 920 females which belong to the following species: Lutzomyia migonei, Lu. pessoai, Lu. fischeri, Lu. misionensis, Lu. lanei, Lu. neivai, Lu. shannoni, and Lu. monticola, in an attempt to verify natural infection by Leishmania (Viannia), the causative agent of ACL. Le. (Viannia) infections were demonstrated by DNA amplification from two Lu. pessoai and one Lu. misionensis female. Lu. pessoai have been found with leptomonas in the gut believed to be Le. (V.) braziliensis in other endemic areas of northeastern and southeastern Brazil. However, Lu. misionensis has never been found carrying a natural infection of Le. (Viannia).

Limiting factors in successful preservation of cadaveric kidneys with ischemia time exceeding 50 hours.

The results of 61 cadaveric allografts preserved for 30 to 76 hours were analyzed to determine the effect of cold ischemia time, the method of preservation, and the type of immunosuppression on early graft viability and long-term graft survival. Preservation in cold storage up to 50 hours gave a low incidence of nonfunction (4%) and of posttransplant dialysis (20%) and a high rate of function both at 1 month (96%) and at 2 years (60%). Cold ischemia time greater than 50 hours caused a significantly increased need for dialysis (58%) but without appreciable difference in graft function at 1 month or at 2 years. Preservation by machine had no advantage over preservation by simple cold storage when the cold ischemia time was less than 50 hours. When cold ischemia time exceeded 50 hours, machine preservation was associated with a significantly reduced incidence of posttransplant dialysis but without significant differences in long-term function at 2 years. With up to 50 hours of cold ischemia and providing there was no ATN, CsA had little nephrotoxicity and gave excellent graft function at 1 month and at 2 years. However, the nephrotoxicity of CsA was markedly increased when the preservation interval exceeded 50 hours, resulting in a significantly increased rate of primary nonfunction and the need for dialysis with a significant decrease in graft function at 1 month and at 2 years. The nephrotoxicity of CsA was considerably decreased or eliminated without affecting its powerful immunosuppressive property when initial immunosuppression was begun with azathioprine with sequential conversion to CsA when graft function was fully established. It is recommended that when cold ischemia is long or when there is ATN, CsA should be used as a sequential therapy to azathioprine after graft diuresis or, alternatively, in much smaller doses as part of a combination therapy with azathioprine.

The place of Sugiura operation for portal hypertension and bleeding esophageal varices.

Fifty patients with portal hypertension and bleeding varices aged 10 months to 72 years were treated with a modified Sugiura, nonshunt operation (n = 26) or shunting procedures (n = 24) in accordance with the following predetermined therapeutic protocol: after resuscitation and diagnostic endoscopy, an emergency mesocaval shunt procedure was carried out if bleeding could not be stopped (group 1, n = 10). When bleeding could be stopped, the patients underwent full investigation and were then treated with either the distal splenorenal (DSR) shunt if the criteria of Warren were satisfied (group 2, n = 14) or with a modified Sugiura procedure in all other circumstances (group 3, n = 26). Patients were evaluated at 1.5 to 6 years. The rates for operative deaths, recurrent hemorrhage, encephalopathy, late deaths, and actuarial patient survival at 6 years were as follows: 20%, 30%, 30%, 20%, and 60% for group 1; 14.3%, 14.3%, 14.3%, 7.2%, and 79% for group 2; and 7.7%, 3.4%, 0%, 0%, and 93% for group 3, respectively. Within 3 months after the Sugiura operation, varices disappeared in 95% of patients and hypersplenism was relieved in all. Major complications were gastric and esophageal leaks in two patients (fatal in one) and temporary dysphagia in six. We conclude that the modified Sugiura nonshunt operation is probably the preferable treatment for variceal hemorrhage in the nonalcoholic patient because it is effective in arresting hemorrhage, has low operative mortality, low recurrence rate, no encephalopathy, and excellent survival rates.