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111.
Passos XS Costa CR Araújo CR Nascimento ES e Souza LK Fernandes Ode F Sales WS Silva Mdo R 《Mycopathologia》2007,163(3):145-151
In this work, we collect data from surveys of bloodstream Candida isolates performed in Brazil from 1996 to 2004. Besides, we analyzed the species distribution of bloodstream Candida isolates together with potential risk factors for candidemia and the susceptibility profile of these isolates in patients
from Hospital das Clínicas in Goiania city, Brazil. Blood samples were collected in the admission day and on every 7 days,
in the intensive care unit (ICU) of a tertiary hospital. Candida isolates were identified by standard protocols that included germ tube formation, chlamydoconidia production on cornmeal
agar and sugar fermentation and assimilation tests. Data of patients were recorded and analyzed according to age at the time
of diagnosis, gender and presence of potential risk factors. Statistical analysis was used to determine if the time of hospital
permanence increased Candida colonization in ICU patients’ blood. The antifungal susceptibility testing was performed by broth microdilution method according
to document NCCLS/CLSI M27–A2. Among the 345 blood samples cultured, candidemia was recovered in 33 patients, which were isolated
51.5% of Candida non-albicans. Fungemia was associated with long-term hospitalization. Fluconazole, itraconzole, voriconazole and amphotericin B exhibited
a potent activity against all isolates of Candida. Voriconazole MICs were much low for all isolates tested. This work confirms data of increase of Candida non-albicans species in bloodstream in ICU and shows that voriconazole in vitro activity was higher than those of itraconazole, fluconazole and amphotericin B. 相似文献
112.
Neves FO Abreu PA Vasconcellos SA de Morais ZM Romero EC Nascimento AL 《Archives of microbiology》2007,188(5):523-532
This study examined four genes encoding for predicted membrane proteins selected from the genome sequences of Leptospira interrogans. Genes were cloned and the proteins expressed in E. coli. Immunoblotting analysis of the recombinants with sera from early and convalescent phases of a leptospirosis patient showed
that two proteins, namely Lp29 and Lp49, were reactive with serum from both phases of the illness. These data were further
confirmed in enzyme-linked immunosorbent assay using sera from both phases of seventeen confirmed leptospirosis specimens,
suggesting that these proteins are presented to the host immune system during infection. In the early phase, anti-Lp29 IgM
was detected in all sera when microscopic agglutination tests (MAT), the reference method for diagnosis of leptospirosis,
were negative. The gene encoding Lp49 is conserved among five tested leptospiral pathogenic serovars, while Lp29 is present
in serovars that are predominant in urban settings. These recombinant antigens might be valuable for serodiagnosis of both
phases of leptospirosis. 相似文献
113.
Ribeiro ML DaMatta RA Diniz JA de Souza W do Nascimento JL de Carvalho TM 《Fish & shellfish immunology》2007,23(1):178-187
A special interest exists concerning lungfish because they may possess characteristics of the common ancestor of land vertebrates. However, little is known about their blood and inflammatory cells; thus the fine structure, cytochemistry and differential cell counts of coelomic exudate and blood leucocytes were studied in Lepidosiren paradoxa. Blood smear analyses revealed erythrocytes, lymphocytes, monocytes, polymorphonuclear agranulocytes, thrombocytes and three different granulocytes. Blood monocytes and lymphocytes had typical vertebrate morphology. Thrombocytes had large vacuoles filled with a myelin rich structure. The polymorphonuclear agranulocyte had a nucleus morphologically similar to the human neutrophil with no apparent granules. Types I and II granulocytes had eosinophilic granules. Type I granulocytes had round or elongated granules heterogeneous in size, while type II had granules with an electron dense core. Type III granulocyte had many basophilic granules. The order of frequency was: type I granulocyte, followed by lymphocyte, type II granulocyte, monocyte, polymorphonuclear agranulocyte and type III granulocyte. Peroxidase localized mainly at the periphery of the granules from type II granulocytes, while no peroxidase expression was detected in type I granulocytes. Alkaline phosphatase was localized in the granules of type II granulocyte and acid phosphatase cytochemistry also labelled a few vacuoles of polymorphonuclear agranulocyte. About 85% of the coelomic inflammatory exudate cell population was type II granulocyte, 10% polymorphonuclear agranulocyte and 5% macrophages as judged by the nucleus and granule morphology. These results indicate that this lungfish utilises type II granulocytes as its main inflammatory granulocytes and that the polymorphonuclear agranulocyte may also be involved in the inflammatory response. The other two granulocytes appear similar to the mammalian eosinophil and basophil. In summary, this lungfish appears to possess the typical inflammatory granulocytes of teleosts, however, further functional studies are necessary to better understand the polymorphonuclear agranulocyte. 相似文献
114.
Natural antibody--complement dependent neutralization of bovine herpesvirus 4 by human serum 总被引:1,自引:0,他引:1
Machiels B Gillet L Nascimento Brito SD Drion P Delforge C Nizet Y Gianello P Bona C Costes B Markine-Goriaynoff N Vanderplasschen A 《Microbes and infection / Institut Pasteur》2007,9(14-15):1530-1537
In contrast to most gammaherpesviruses, Bovine herpesvirus 4 (BoHV-4) has a broad range of host species both in vitro and in vivo. Several in vitro studies demonstrated that some human cell lines are sensitive or even permissive to BoHV-4. These observations led to the hypothesis that cross-species transmission of BoHV-4 could lead to human infections. In the present study, we investigate the sensitivity of BoHV-4 to neutralization by na?ve human sera in order to determine if humans exhibit innate anti-viral activities against this virus. Our results demonstrate that human sera from na?ve individuals, in contrast to the sera of na?ve subjects from various animal species, neutralize BoHV-4 efficiently. A series of complementary experiments were performed to unravel the mechanism(s) of this neutralization. The data obtained in this study demonstrates that human serum neutralizes BoHV-4 in a complement dependent manner activated by natural antibodies raised against the Galalpha1-3Galbeta1-4GlcNAc-R epitope expressed by bovine cells. 相似文献
115.
A novel leptospiral protein increases ICAM-1 and E-selectin expression in human umbilical vein endothelial cells 总被引:2,自引:0,他引:2
Vieira ML D'Atri LP Schattner M Habarta AM Barbosa AS de Morais ZM Vasconcellos SA Abreu PA Gómez RM Nascimento AL 《FEMS microbiology letters》2007,276(2):172-180
It has been reported previously that activation of vascular endothelium by outer membrane proteins of the spirochetes Borrelia sp. and Treponema sp. resulted in enhanced expression of endothelial cell adhesion molecules. To investigate the role of leptospiral proteins in this process, a predicted lipoprotein encoded by the gene LIC10365 was selected, which belongs to a paralogous family that presents a domain of unknown function, DUF1565. The LIC10365 gene was cloned and the protein expressed in Escherichia coli C43 (DE3) strain using the vector pAE. The recombinant protein tagged with N-terminal hexahistidine was purified by metal-charged chromatography and was used to assess its ability to activate cultured human umbilical vein endothelial cells. The rLIC10365 activated endothelium in such a manner that E-selectin and intercellular adhesion molecule 1 (ICAM-1) became upregulated in a dose-dependent fashion. The LIC10365-encoded protein was identified in vivo in the renal tubules of animal during experimental infection with Leptospira interrogans. Collectively, these results implicate the LIC10365-coding protein of L. interrogans as a potential effector molecule in the promotion of a host inflammatory response. This is the first report of a leptospiral protein capable of up-regulating the expression of endothelial cell adhesion molecules ICAM-1 and E-selectin. 相似文献
116.
Moreno SR Arnobio A De Carvalho JJ Nascimento L Oliveira Timoteo M Olej B Rocha EK Pereira M Bernardo-Filho M Caldas LQ 《Biological research》2007,40(2):131-135
The radiobiocomplexes labeled with technetium-99m (Tc-99m) have been widely used in nuclear medicine in single photon emission computed tomography and in basic research. The aim of this study was to assess the influence of a Nectandra membranacea extract on the bioavailability of the sodium pertechnetate (Na(99m)TcO(4)) radiobiocomplex in rat organs. The animals were treated with a N. membranacea extract (30 mg/ ml), for 6 days. Na(99m)TcO(4) was injected, the organs were isolated and weighed, and the radioactivity was determined in each organ (%ATI/organ). The %ATI/organ was divided by the mass of each organ to calculate the %ATI/g. A significant increase of the %ATI/organ of Na(99m)TcO(4) was observed in muscle and thyroid as well as in the %ATI/g in the heart, kidney and thyroid. These findings could result from the interaction between components of the plant extract and the radiobiocomplex which may influence the uptake Na(99m)TcO(4) in rat organs. Therefore, precaution is suggested in the interpretation of nuclear medicine results in patients using this herb. 相似文献
117.
do Nascimento AM Costa FC Thiemann OH de Oliveira DC 《Zeitschrift für Naturforschung. C, Journal of biosciences》2007,62(5-6):353-356
The dichloromethane extract of Calea uniflora afforded a mixture of two novel chromanones, uniflorol-A (1) and uniflorol-B (2), and one known chromanone, 2,2-dimethyl-6-(1-hydroxyethyl)-chroman-4-one (3). The structures of these compounds were determined by spectroscopic methods. Biological activity of the compounds against Leishmania major promastigotes was evaluated. Mixture of the novel chromanones 1 and 2 showed significant growth inhibition of the parasite in the micrograms per milliliter range. 相似文献
118.
Brain bank of the Brazilian aging brain study group—a milestone reached and more than 1,600 collected brains 总被引:2,自引:0,他引:2
Grinberg LT Ferretti RE Farfel JM Leite R Pasqualucci CA Rosemberg S Nitrini R Saldiva PH Filho WJ;Brazilian Aging Brain Study Group 《Cell and tissue banking》2007,8(2):151-162
INTRODUCTION: Brain banking remains a necessity for the study of aging brain processes and related neurodegenerative diseases. In the present paper, we report the methods applied at and the first results of the Brain Bank of the Brazilian Aging Brain Study Group (BBBABSG) which has two main aims: (1) To collect a large number of brains of elderly comprising non-demented subjects and a large spectrum of pathologies related to aging brain processes, (2) To provide quality material to a multidisciplinar research network unraveling multiple aspects of aging brain processes and related neurodegenerative diseases. METHODS: The subjects are selected from the Sao Paulo Autopsy Service. Brain parts are frozen and fixated. CSF, carotids, kidney, heart and blood are also collected and DNA is extracted. The neuropathological examinations are carried out based on accepted criteria, using immunohistochemistry. Functional status are assessed through a collateral source based on a clinical protocol. Protocols are approved by the local ethics committee and a written informed consent form is obtained. RESULTS: During the first 21 months, 1,602 samples were collected and were classified by Clinical Dementia Rating as CDR0: 65.7%; CDR0.5:12.6%, CDR1:8.2%, CDR2:5.4%, and CDR3:8.1%. On average, the cost for the processing each case stood at 400 US dollars. To date, 14 laboratories have been benefited by the BBBABSG. CONCLUSION: The high percentage of non- demented subjects and the ethnic diversity of this series may be significantly contributive toward aging brain processes and related neurodegenerative diseases understanding since BBBABSG outcomes may provide investigators the answers to some additional questions. 相似文献
119.
E S Nascimento R Figueiró J J Becnel C J P C Araújo-Coutinho 《Revista brasleira de biologia》2007,67(3):519-526
During the studies involving the correlation between the water temperature of the breeding site of Simulium pertinax larvae and the infection prevalence by microsporidia, developed in the Andorinhas river, Magé, RJ, weekly samples of blackfly larvae were taken within a two-year period (2001-2002 and 2003-2004), and it was noticed that the infections by Amblyospora sp. were more prevalent when compared to infections by Polydispyrenia sp. in larvae. It was also observed that the infections do not follow the same pattern, since the genus Amblyospora was recorded almost every month during the study with the exception of December, 2001. In the results of correlation between the environmental water temperature and the microsporidia infection rates, it was observed that for the first period studied, there was a high negative correlation, while during the second period there was absence correlation. On the other hand, the Amblyospora sp. infection rates prove that the correlation was high and significant in the first period, but was not significant in the second sampling period and Polydispyrenia sp. showed absence correlation in both periods. 相似文献
120.
Jesus Ronald Ferreira Santos Ana Nunes Nandyara Bianca dos Santos Jeannie Nascimento Melo Francisco Tiago Vasconcelos 《Systematic parasitology》2022,99(6):761-769
Systematic Parasitology - Nematodes collected from the stomach and large intestine of Rhinoclemmys punctularia (Daudin) from the eastern Amazon, Brazil, are assigned to a new genus, Vogtnema n.... 相似文献