oalib

Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99

Submit

Any time

4 ( 1 )

2020 ( 56 )

2019 ( 350 )

2018 ( 410 )

Custom range...

Search Results: 1 - 10 of 217131 matches for " Narcisa Cunha-e-Silva "
All listed articles are free for downloading (OA Articles)
Page 1 /217131
Display every page Item
Cell fractionation of parasitic protozoa: a review
Souza, Wanderley de;Cunha-e-Silva, Narcisa Leal da;
Memórias do Instituto Oswaldo Cruz , 2003, DOI: 10.1590/S0074-02762003000200001
Abstract: cell fractionation, a methodological strategy for obtaining purified organelle preparations, has been applied successfully to parasitic protozoa by a number of investigators. here we present and discuss the work of several groups that have obtained highly purified subcellular fractions from trypanosomatids, apicomplexa and trichomonads, and whose work have added substantially to our knowledge of the cell biology of these parasites.
Cell fractionation of parasitic protozoa: a review
Souza Wanderley de,Cunha-e-Silva Narcisa Leal da
Memórias do Instituto Oswaldo Cruz , 2003,
Abstract: Cell fractionation, a methodological strategy for obtaining purified organelle preparations, has been applied successfully to parasitic protozoa by a number of investigators. Here we present and discuss the work of several groups that have obtained highly purified subcellular fractions from trypanosomatids, Apicomplexa and trichomonads, and whose work have added substantially to our knowledge of the cell biology of these parasites.
Choline acetyltransferase detection in normal and denervated electrocyte from Electrophorus electricus (L.) using a Confocal Scanning Optical Microscopy Analysis
NUNES-TAVARES, NILSON;CUNHA-E-SILVA, NARCISA LEAL;HASSóN-VOLOCH, AíDA;
Anais da Academia Brasileira de Ciências , 2000, DOI: 10.1590/S0001-37652000000300007
Abstract: acetylcholine is the neurotransmitter responsible for the transmission of impulses from cholinergic neurons to cells of innervated tissues. its biosynthesis is catalyzed by the enzyme choline acetyltransferase that is considered to be a phenotypically specific marker for cholinergic system. it is well known that the regulation of choline acetyltransferase activity under physiological and pathological conditions is important for development and neuronal activities of cholinergic functions. we observed the distribution of choline acetyltransferase in sections from the normal and denervated main electric organ sections of electrophorus electricus (l.) by immunofluorescence using a anti-choline acetyltransferase antibody. the animals were submitted to a surgical procedure to remove about 20 nerves and after 30 and 60 days, they were sacrificed. after 30 days, the results from immunohistochemistry demonstrated an increase on the choline acetyltransferase distribution at denervated tissue sections when compared with the sections from the normal contralateral organ. a very similar labeling was observed between normal and denervated tissue sections of the animals after 60 days. however, choline acetyltransferase activity (nmolesach/ min/ mg of protein) in extracts obtained from electrocyte microsomal preparation, estimated by fonnun's method (fonnun 1975), was 70% lower in the denervated extracts.
Choline acetyltransferase detection in normal and denervated electrocyte from Electrophorus electricus (L.) using a Confocal Scanning Optical Microscopy Analysis
NUNES-TAVARES NILSON,CUNHA-E-SILVA NARCISA LEAL,HASSóN-VOLOCH AíDA
Anais da Academia Brasileira de Ciências , 2000,
Abstract: Acetylcholine is the neurotransmitter responsible for the transmission of impulses from cholinergic neurons to cells of innervated tissues. Its biosynthesis is catalyzed by the enzyme Choline acetyltransferase that is considered to be a phenotypically specific marker for cholinergic system. It is well known that the regulation of Choline acetyltransferase activity under physiological and pathological conditions is important for development and neuronal activities of cholinergic functions. We observed the distribution of Choline acetyltransferase in sections from the normal and denervated main electric organ sections of Electrophorus electricus (L.) by immunofluorescence using a anti-Choline acetyltransferase antibody. The animals were submitted to a surgical procedure to remove about 20 nerves and after 30 and 60 days, they were sacrificed. After 30 days, the results from immunohistochemistry demonstrated an increase on the Choline acetyltransferase distribution at denervated tissue sections when compared with the sections from the normal contralateral organ. A very similar labeling was observed between normal and denervated tissue sections of the animals after 60 days. However, Choline acetyltransferase activity (nmolesACh/ min/ mg of protein) in extracts obtained from electrocyte microsomal preparation, estimated by Fonnun's method (Fonnun 1975), was 70% lower in the denervated extracts.
Trypanosoma cruzi Epimastigotes Are Able to Store and Mobilize High Amounts of Cholesterol in Reservosome Lipid Inclusions
Miria G. Pereira, Ernesto S. Nakayasu, Celso Sant'Anna, Nuccia N. T. De Cicco, Georgia C. Atella, Wanderley de Souza, Igor C. Almeida, Narcisa Cunha-e-Silva
PLOS ONE , 2011, DOI: 10.1371/journal.pone.0022359
Abstract: Background Reservosomes are lysosome-related organelles found in Trypanosoma cruzi epimastigotes. They represent the last step in epimastigote endocytic route, accumulating a set of proteins and enzymes related to protein digestion and lipid metabolism. The reservosome matrix contains planar membranes, vesicles and lipid inclusions. Some of the latter may assume rectangular or sword-shaped crystalloid forms surrounded by a phospholipid monolayer, resembling the cholesterol crystals in foam cells. Methodology/Principal Findings Using Nile Red fluorimetry and fluorescence microscopy, as well as electron microscopy, we have established a direct correlation between serum concentration in culture medium and the presence of crystalloid lipid inclusions. Starting from a reservosome purified fraction, we have developed a fractionation protocol to isolate lipid inclusions. Gas-chromatography mass-spectrometry (GC-MS) analysis revealed that lipid inclusions are composed mainly by cholesterol and cholesterol esters. Moreover, when the parasites with crystalloid lipid-loaded reservosomes were maintained in serum free medium for 48 hours the inclusions disappeared almost completely, including the sword shaped ones. Conclusions/Significance Taken together, our results suggest that epimastigote forms of T. cruzi store high amounts of neutral lipids from extracellular medium, mostly cholesterol or cholesterol esters inside reservosomes. Interestingly, the parasites are able to disassemble the reservosome cholesterol crystalloid inclusions when submitted to serum starvation.
CONTROLE DE QUALIDADE DE IMATUROS DE Cochliomyia macellaria (FABRICIUS) (DIPTERA: CALLIPHORIDAE) EM ESTOQUES
CUNHA-E-SILVA,SANDRA LUCIA; MILWARD-DE-AZEVEDO,ELIANE M.V.;
Parasitología al día , 1999, DOI: 10.4067/S0716-07201999000100004
Abstract: quality control of cochliomyia macellaria (fabricius) (diptera: calliphoridae) imatures in colony quality control of cochliomyia macellaria (fabricius) (diptera: calliphoridae) larvae and pupae in colony was observed during eight consecutive generations. a diet consisting of decomposing horse flesh was used, and the relation of 0.02 g egg mass/ 200 g diet was established. the larval and pupal viability at 27 oc and 30 oc temperature, 65 ± 10% ur and 14 h photofase, respectively, were greater than 80%. the egg to pupae period and the body mass of postfeeding larvae variation were 4.7-7.0 days and 59.40-70.30 mg, respectively. the emergence ocurred 8.0-12.0 days after the neolarvae innoculation in diet. the study has not show a linear relation between the analised characteristic and monitored generations
Estudo comparado do desenvolvimento de dois morfotipos larvais de Cochliomyia macellaria (Fabricius) (Diptera, Calliphoridae)
Cunha-e-Silva, Sandra L.;Milward-de-Azevedo, Eliane M.V.;
Revista Brasileira de Zoologia , 1992, DOI: 10.1590/S0101-81751992000200003
Abstract: the possible dissimilitudes relating to the duration of the egg incubation period and larval stage of cochliomyia macellaria (fab., 1775) from offsprings of females from larvae with and without pigmentation on malpighi tubules, morphotype 1 and 2, respectively, was questioned. the experiment was conducted in climatized chamber regulated at 30oc, 65±10% rh and 14 hour photophase. no significant difference was observed on average duration of first and second larval instars berween the two morphotypes, taking into account not only the conventional interpretation for the reading of different development phases of the larval stages (morphotype 1:11.0 and 11.9 hours and morphotype 2:11.7 and 12.7 hours for first and second instars, respectively), but also the reading made through the interpretation preconized by snodgrass & hinton (morphotype 1:10.3 and 9.6 hours and morphotype 2:9.8 and 10.8 hours for the first and second instars, respectively). the incubation period was significantly longer for eggs posited by females from non-pigmented larvae.
Aspectos da biologia da reprodu??o e longevidade de Cochliomyia macellaria (Fabricius) (Diptera, Calliphoridae), em condi??es experimentais. I. casais agrupados
Cunha-e-Silva, Sandra Lucia;Milward-de-Azevedo, Eliane M.V;
Revista Brasileira de Zoologia , 1996, DOI: 10.1590/S0101-81751996000400010
Abstract: in the present study we estimed the longevity and reproductive potential of cochliomyia macellaria (fabricius, 1775), in different densities of grouped pairs, as a function of time of collection. the study was divided into two phases and conducted in an incubator regulated at 27oc, 65±10% rh and 14 hours photoperiod. forty and 20 pairs/replication were used, corresponding to the third and fourth generation originating from a laboratory colony. egg masses were collected at 8:00 and 17:00 hours daily. the results obtained were influenced by the variables established. the ovipositing peak occurred 20 days after the emergence of females belonging to the third generation. this peak occurred earlier in fourth generation females, i.e., 11 days after imago emergence. these peaks corresponded to a total of 0,30 and 0,23g of egg masses, respectively. the survival curves for adults were estimated by the weibull method.
CONTROLE DE QUALIDADE DE IMATUROS DE Cochliomyia macellaria (FABRICIUS) (DIPTERA: CALLIPHORIDAE) EM ESTOQUES
SANDRA LUCIA CUNHA-E-SILVA,ELIANE M.V. MILWARD-DE-AZEVEDO
Parasitología al día , 1999,
Abstract: RESUMO O controle de qualidade de larvas e pupas de Cochliomyia macellaria (Fabricius) (Diptera: Calliphoridae), mantidas em estoques, foi monitorado durante oito gera es consecutivas. Uma dieta consistindo de carne eqüina putrefata foi utilizada, estabelecendo-se a rela o de 0.02 g de massa de ovos / 200 g de dieta. A taxa de sobrevivência larval e pupal a 27 oC e 30 oC de temperatura, 65 ± 10% UR e 14 h de fotofase, respectivamente, foi superior a 80%. O período de ovo a pupa e a massa corporal de larvas pós-alimentadas oscilou entre 4.7-7.0 dias e 59.40-70.30 mg, respectivamente. A emergência ocorreu 8.0-12.0 dias após a inocula o das neolarvas na dieta. O estudo n o sugeriu uma rela o linear entre as características analisadas e as gera es monitoradas. QUALITY CONTROL OF Cochliomyia macellaria (FABRICIUS) (DIPTERA: CALLIPHORIDAE) IMATURES IN COLONY Quality control of Cochliomyia macellaria (Fabricius) (Diptera: Calliphoridae) larvae and pupae in colony was observed during eight consecutive generations. A diet consisting of decomposing horse flesh was used, and the relation of 0.02 g egg mass/ 200 g diet was established. The larval and pupal viability at 27 oC and 30 oC temperature, 65 ± 10% UR and 14 h photofase, respectively, were greater than 80%. The egg to pupae period and the body mass of postfeeding larvae variation were 4.7-7.0 days and 59.40-70.30 mg, respectively. The emergence ocurred 8.0-12.0 days after the neolarvae innoculation in diet. The study has not show a linear relation between the analised characteristic and monitored generations
Two special organelles found in Trypanosoma cruzi
SOUZA, WANDERLEY DE;CARREIRO, ISABEL PORTO;MIRANDA, KILDARE;SILVA, NARCISA L. CUNHA E;
Anais da Academia Brasileira de Ciências , 2000, DOI: 10.1590/S0001-37652000000300016
Abstract: we review here two unique organelles from trypanosoma cruzi. one of them is the acidocalcisome, cytoplasmic vacuoles containing a very high ca2+ concentration and a ca2+ - h+ translocating atpase activity, present in all trypanosomatids. the other organelle is the reservosome, site of accumulation of endocytosed macromolecules, very rich in cysteine proteinase, that is present only in epimastigote forms of trypanosomes belonging to the schyzotrypanum sub-genus.
Page 1 /217131
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.