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91.
Danilo O. Carvalho Andrew R. McKemey Luiza Garziera Renaud Lacroix Christl A. Donnelly Luke Alphey Aldo Malavasi Margareth L. Capurro 《PLoS neglected tropical diseases》2015,9(7)
The increasing burden of dengue, and the relative failure of traditional vector control programs highlight the need to develop new control methods. SIT using self-limiting genetic technology is one such promising method. A self-limiting strain of Aedes aegypti, OX513A, has already reached the stage of field evaluation. Sustained releases of OX513A Ae. aegypti males led to 80% suppression of a target wild Ae. aegypti population in the Cayman Islands in 2010. Here we describe sustained series of field releases of OX513A Ae. aegypti males in a suburb of Juazeiro, Bahia, Brazil. This study spanned over a year and reduced the local Ae. aegypti population by 95% (95% CI: 92.2%-97.5%) based on adult trap data and 81% (95% CI: 74.9-85.2%) based on ovitrap indices compared to the adjacent no-release control area. The mating competitiveness of the released males (0.031; 95% CI: 0.025-0.036) was similar to that estimated in the Cayman trials (0.059; 95% CI: 0.011 – 0.210), indicating that environmental and target-strain differences had little impact on the mating success of the OX513A males. We conclude that sustained release of OX513A males may be an effective and widely useful method for suppression of the key dengue vector Ae. aegypti. The observed level of suppression would likely be sufficient to prevent dengue epidemics in the locality tested and other areas with similar or lower transmission. 相似文献
92.
The photophysiology of turf algal communities was studied in situ on a temperate reef off the coast of South Australia. Algal communities were grown on artificial substrate at depths of 2, 4, and 10 m. To investigate the response of the algal communities to changing light environments in both the short and long term, reciprocal transplantation experiments were conducted among these depths on a seasonal basis. The extent of photoinhibition was assessed every 3 h for the first 2 days following transplantation and then on a daily basis for 16 days after transplantation. Photosynthetic acclimation was assessed using photosynthesis–light curves obtained from transplanted and non‐transplanted turfs after the acclimation period. Transplanted turfs responded very quickly to the light shift. Algae acclimated to low light (10 m depth) were highly susceptible to photoinhibition and photodamage, having greater decreases in maximum and effective quantum yields than turfs from shallower depths. Yield recovery and acclimation usually occurred very rapidly in algae from all depths (3–5 days), but were faster in spring and summer compared with winter. Changes in photosynthetic capacity (across seasons, depths, and after transplantation to a different depth) were accompanied by changes in respiration, so that the ratio of net to gross photosynthetic capacity (Pmnet : Pmgross) remained high and constant over the whole range of light levels. We discuss the possible acclimation strategies of turfs, taking into account the balance between photoacclimation, production, and growth strategy. 相似文献
93.
Seasonal variations in physiological parameters of phytoplankton across the North Atlantic 总被引:1,自引:0,他引:1
Kyewalyanga Margareth N.; Platt Trevor; Sathyendranath Shubha; Lutz Vivian A.; Stuart Venetia 《Journal of plankton research》1998,20(1):17-42
Variations in the shapes of the action and absorption spectra,and the physiological parameters of phytoplankton [B, the biomass(B)-specific initial slope of the photosynthesis-irradiancecurve; the plateau of the curve; m), themaximum quantum yield of photosynthesis], were studied. Datawere collected in the North Atlantic in five biogeochemicalprovinces for two seasons: in fall of 1992 and spring of 1993.Further, some nine independent variables were tested for theirability to predict the physiological parameters, using linearregression analyses. It was found that the parameters were morevariable between seasons than between provinces, although thedifferences in the spectral shapes between provinces were significant.It was also shown that several independent variables (aloneor in combination) were able to predict a significant fractionof the total variance in the parameters. However, the correlationbetween variables and parameters differed unsystematically bothbetween provinces and seasons. The results suggest that predictinga parameter from an independent variable would have to be carriedout at a province level: the relationship changed or disappearedwhen data from two or more provinces were pooled. 相似文献
94.
Eliane A Fávaro Adriano Mondini Margareth R Dibo Angelita A C Barbosa Alvaro E Eiras Francisco Chiaravalloti Neto 《Journal of vector ecology》2008,33(1):8-16
We compared the presence and mean number of eggs from oviposition traps with the mean number of Aedes aegypti females captured by manual aspirators and by MosquiTRAPs to determine the sensitivity of each method and to standardize each indicator. The collections of adults and eggs were performed over 23 weeks in six neighborhoods of Mirassol, state of S?o Paulo, Brazil. A better assessment of indicators required larger number of MosquiTRAPs, but to quantify the number of females per house, one trap was sufficient. The sensitivities of MosquiTRAPs and manual aspirations to detect the presence of A. aegypti females were similar, but were lower compared to oviposition traps. The correlation coefficients between the number of females captured by MosquiTRAPs and manual aspirations and the number of eggs from oviposition traps were low, which may be a consequence of each method showing different stages of the mosquito life cycle. 相似文献
95.
Gallo MB Marques AS Vieira PC da Silva MF Fernandes JB Silva M Guido RV Oliva G Thiemann OH Albuquerque S Fairlamb AH 《Zeitschrift für Naturforschung. C, Journal of biosciences》2008,63(5-6):371-382
Hexanic, methanolic, and hydroalcoholic extracts, and 34 isolated compounds from Vitex polygama Cham. (Lamiaceae, formely Verbenaceae) and Siphoneugena densiflora O. Berg (Myrtaceae) were screened for their trypanocidal effects on bloodstream forms of Trypanosoma cruzi and T brucei, as well as for their enzymatic inhibitory activities on glycosomal glyceraldehyde-3-phosphate dehydrogenase (gGAPDH) and trypanothione reductase (TR) enzymes from T cruzi and adeninephosphoribosyl transferase (APRT) enzyme from Leishmania tarentolae. In general, polar extracts displayed strong effects and some of the tested compounds have shown good results in comparison to positive controls of the bioassays. 相似文献
96.
Carlos André Nunes Jatobá Adriana Augusto de Rezende Sarah Jane de Paiva Rodrigues Maria Margareth de Almeida Câmara Maria das Graças Almeida Francisco Freire-Neto Luiz Reginaldo Menezes da Rocha Aldo Cunha da Medeiros José Brandão-Neto Maria Célia de Carvalho Formiga Ítalo Medeiros de Azevedo Ana Maria de Oliveira Ramos 《Biometals》2008,21(2):171-178
Tamoxifen (TX), a drug used in the treatment of breast cancer, may cause hepatic changes in some patients. The consequences
of its use on the liver tissues of rats with or without diabetes mellitus (DM) have not been fully explored. The purpose of
this study was to evaluate the correlation between plasma hepatic enzyme levels and the presence of iron overload in the hepatic
tissue of female Wistar rats with or without streptozotocin-induced DM and using TX. Female rats were studied in control groups:
C-0 (non-drug users), C-V (sorbitol vehicle only) and C-TX (using TX). DM (diabetic non-drug users) and DM-TX (diabetics using
TX) were the test groups. Sixty days after induced DM, blood samples were collected for glucose, alanine aminotransferase
(ALT), aspartate aminotransferase (AST) alkaline phosphatase (ALP) and bilirubin measures. Hepatic fragments were processed
and stained with hematoxylin and eosin, Masson’s trichrome, Perls. The hepatic iron content was quantified by atomic absorption
spectrometry. AST, ALT and ALP levels were significantly elevated in the DM and DM-TX groups, with unchanged bilirubin levels.
Liver iron overload using Perls stain and atomic absorption spectrometry were observed exclusively in groups C-TX and DM-TX.
There was positive correlation between AST, ALT and ALP levels and microscopic hepatic siderosis intensity in group DM-TX.
In conclusion, TX administration is associated with liver siderosis in diabetic and non-diabetic rats. In addition, TX induced
liver iron overload with unaltered hepatic function in non-diabetic rats and may be a useful tool for investigating the biological
control of iron metabolism. 相似文献
97.
Dibo MR Chierotti AP Ferrari MS Mendonça AL Chiaravalloti Neto F 《Memórias do Instituto Oswaldo Cruz》2008,103(6):554-560
The purpose of this study was to examine the relationship between Aedes aegypti egg and adult density indices, dengue fever and climate in Mirassol, state of S?o Paulo, Brazil, between November 2004-November 2005. Weekly collections of adults and eggs were made using, respectively, manual aspirators and oviposition traps that produced four entomological indices (positivity and average of females and eggs). Weekly incidence coefficients were calculated based on dengue cases. Each week, the data obtained from entomological indices were related to each other, dengue, and climate variables. The first index to show an association with dengue transmission was the female average, followed by female positivity and egg average. Egg positivity did not show a relationship with risk for dengue, but was sensitive to identifying the presence of the vector, principally in dry seasons. The relationship between climatic factors, the vector and the disease found in this study can be widely employed in planning and undertaking dengue surveillance and control activities, but it is a tool that has not been considered by the authorities responsible for controlling the disease. In fact, this relationship permits the use of information about climate for early detection of epidemics and for establishing more effective prevention strategies than currently exist. 相似文献
98.
Ewa Markiewicz Rachel Venables Mauricio-Alvarez-Reyes Roy Quinlan Margareth Dorobek Irena Hausmanowa-Petrucewicz Christopher Hutchison 《Journal of structural biology》2002,140(1-3)
Emery–Dreifuss muscular dystrophy (EDMD) is caused by mutations in the gene encoding the nuclear membrane protein emerin (X-linked EDMD) or in the gene encoding lamins A/C (autosomal dominant EDMD). One hypothesis explaining the disease suggests that the mutations lead to weakness of the nuclear lamina. To test this hypothesis we investigated lamin solubility and distribution in skin fibroblasts from X-EDMD patients. Using in situ extraction of cells and immunofluorescence microscopy or biochemical fractionation and immunoblotting, we found that all lamin subtypes displayed increased solubility properties in fibroblasts from X-EDMD patients compared to normal individuals. Lamin and emerin solubility was mildly increased in fibroblasts from an X-EDMD carrier. Biochemical fractionation and immunoblotting also indicated that lamin C but no other lamin became redistributed from the nuclear lamina to the nucleoplasm in X-EDMD fibroblasts. Indirect immunofluorescence and confocal microscopy studies using lamin A- and lamin C-specific antibodies confirmed that lamin C but not lamin A became redistributed to the nucleoplasm. Interestingly, the lamin A/C binding protein LAP2α was also mislocalized in X-EDMD fibroblasts. 相似文献
99.
Marinho CR Barbosa LS de Azevedo AC Queiroz MM Valgode MA Coelho VM 《Memórias do Instituto Oswaldo Cruz》2003,98(7):937-938
The aim of this note was to record for the first time the finding of Hemilucilia segmentaria acting as biological vector of Dermatobia hominis, during a study of the diversity of Calliphoridae at Reserva Biol gica do Tinguá, Rio de Janeiro, Brazil. The insects were captured using traps baited with chicken vicera, for a period of 28-30 h twice per month. In the period of one year, 1987 insects were collected, 7.5% of which belonged to the H. segmentaria; of these a female was captured in May 2001, carrying a mass of 20 eggs on the left side of its abdomen. 相似文献
100.
Evans Blue as a Simple Method to Discriminate Mosquitoes’ Feeding Choice on Small Laboratory Animals
Ceres Maciel André Fujita Daniele I. Gueroni Anderson D. Ramos Margareth L. Capurro Anderson Sá-Nunes 《PloS one》2014,9(10)