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91.
Scuracchio P Vieira SD Dourado DA Bueno LM Colella R Ramos-Sanchez EM Lima GF Inoue J Sanchez MC Di Santi SM 《Revista do Instituto de Medicina Tropical de S?o Paulo》2011,53(1):55-59
Malaria in Brazil is endemic in the Amazon region, but autochthonous cases with low parasitaemia occur in the Atlantic Forest area of the country. According to Brazilian legislation no test is mandatory for blood donors from non-endemic areas. However if they have traveled to malaria transmission regions they are deferred for six months before they can donate. This report describes a transfusion-transmitted malaria case in Sao Paulo, Brazil, where one recipient received infected blood and developed the disease. He lived in Sao Paulo and had no previous transfusion or trips to endemic areas, including those of low endemicity, such as Atlantic Forest. Thick blood smears confirmed Plasmodium malariae. All donors lived in Sao Paulo and one of them (Donor 045-0) showed positive hemoscopy and PCR. This asymptomatic donor had traveled to Juquia, in the Atlantic Forest area of S ao Paulo State, where sporadic cases of autochthonous malaria are described. DNA assay revealed P. malariae in the donor's (Donor 045-0) blood. Serum archives of the recipient and of all blood donors were analyzed by ELISA using both P. vivax and P. falciparum antigens, and IFAT with P. malariae. Donor 045-0's serum was P. malariae IFAT positive and the P. vivax ELISA was reactive. In addition, two out of 44 donors' archive sera were also P. vivax ELISA reactive. All sera were P. falciparum ELISA negative. This case suggests the need of reviewing donor selection criteria and deferral strategies to prevent possible cases of transfusion-transmitted malaria. 相似文献
92.
93.
S. Pelo R. Boniello A. Moro G. Gasparini P.F. Amoroso 《International journal of oral and maxillofacial surgery》2010,39(3):227-234
Extensive resorption of the mandible increases the interarch space and rehabilitation with traditional dentures is often unsatisfactory due to the superficialization of intraoral muscles. A study of 19 patients who underwent augmentation of an atrophic mandible using a bilateral two-step osteotomy and interpositional bone graft technique is presented. Three horizontal bone cuts (one in the intraforamina and two in the molar region) were made and jointed together by two short vertical bone cuts mesialy to the mental nerve. The cranial fragment was lifted and the iliac bone graft was interposed recreating the correct intermaxillary relationship. A broad vascular pedicle was maintained during surgery, ensuring nutrition from the lingual side, essential to reduce resorption of the bone graft and cranial fragment. 141 Biomet 3i Osseotite® implants were placed. Patients were rehabilitated with a full-arch implant-supported fixed prosthesis or an implant-supported overdenture. This clinical study describes the resorption process over a 4 year follow-up. 3 of 19 suffered from persistent neurosensitive disturbances. In conclusion, bilateral two-step osteotomy in association with interpositional bone graft is a reliable surgical means to recreate the anatomical morphology of the mandible. 相似文献
94.
Claire Valiente Moro Jean Thioulouse Claude Chauve Philippe Normand Lionel Zenner 《Research in microbiology》2009,160(1):63-70
Dermanyssus gallinae (Arthropoda, Mesostigmata) is suspected to be involved in the transmission of a wide variety of pathogens, but nothing is known about its associated non-pathogenic bacterial community. To address this question, we examined the composition of bacterial communities in D. gallinae collected from standard poultry farms in Brittany, France. Genetic fingerprints of bacterial communities were generated by temporal temperature gradient gel electrophoresis (TTGE) separation of individual polymerase chain reaction (PCR)-amplified 16S rRNA gene fragments, followed by DNA sequence analysis. Most of the sequences belonged to the Proteobacteria and Firmicute phyla, with a majority of sequences corresponding to the Enterobacteriales order and the Staphylococcus genus. By using statistical analysis, we showed differences in biodiversity between poultry farms. We also determined the major phylotypes that compose the characteristic microbiota associated with D. gallinae. Saprophytes, opportunistic pathogens and pathogenic agents such as Pasteurella multocida, Erysipelothrix rhusiopathiae and sequences close to the genus Aerococcus were identified. Endosymbionts such as Schineria sp., Spiroplasma sp. Anistosticta, “Candidatus Cardinium hertigii” and Rickettsiella sp. were also present in the subdominant bacterial community. Identification of potential targets within the symbiont community may be considered in the future as a means of ectoparasite control. 相似文献
95.
Allogeneic bone marrow transplant (BMT) or hematopoietic stem cell transplant (HSCT) is one of the most arduous cancer treatments to endure and is therefore likely to have more long-term sequelae. The aim of this article is to discuss and analyze the results of international scientific articles on the psychological impact of HSCT, based on psychoanalytic concepts. We focus on the concepts of psychosocial distress, quality of life (QOL), posttraumatic stress disorder (PTSD) and posttraumatic growth (PTG). 相似文献
96.
Juan Casado Flores Montserrat Nieto Moro Sonsoles Berrón Raquel Jiménez Julio Casal 《European journal of pediatrics》2010,169(5):581-584
Pleural effusion is increasingly reported in children. Standard culture of blood or pleural fluid is frequently negative and
molecular diagnosis by polymerase chain reaction is not available in all hospitals. The Binax NOW Streptococcus pneumoniae Antigen test (Binax, Portland, USA) is a rapid immunochromatographic test (ICT) for the detection of the C polysaccharide
antigen. We evaluated the Binax NOW test on the pleural fluid of 73 children hospitalized with pleural effusion over a period
of 4 years. In our sample, the sensitivity and specificity of ICT were high (88% and 71%, respectively), with a positive predictive
value of 96%. Detection of the pneumococcal antigen in pleural fluid by ICT is easy and quick, and enables us to identify
the pneumococcal origin of the effusion, thus, making the treatment of complicated pneumonia suitably and early. 相似文献
97.
CK2 is a pleiotropic, ubiquitous, and constitutively active protein kinase (PK), with both cytosolic and nuclear localization in most mammalian cells. The holoenzyme is generally composed of two catalytic (α and/or α′) and two regulatory (β) subunits, but the free α/α′ subunits are catalytically active by themselves and can be present in cells under some circumstances. CK2 catalyzes the phosphorylation of more than 300 substrates characterized by multiple acidic residues surrounding the phosphor‐acceptor amino acid, and, consequently, it plays a key role in several physiological and pathological processes. But how can one kinase orchestrate all these tasks faithfully? How is it possible that one kinase can, despite all pleiotropic characteristics of PKs in general, be involved in so many different biochemical events? Is CK2 a druggable target? Several questions are still to be clearly answered, and this review is an occasion for a fruitful discussion. © 2009 Wiley Periodicals, Inc. Med Res Rev, 30, No. 3, 419–462, 2010 相似文献
98.
Vanessa C Borges Gabriele Dadalt Lucielli Savegnago Angélica V Moro Joao B T Rocha Cristina W Nogueira 《Toxicology in vitro》2007,21(3):387-391
Organochalcogens are important intermediates and useful reagents in organic synthesis. Recent data from our laboratory demonstrated that bis and tris-selenide alkene derivatives are attractive synthetic targets because of their chemio-, regio- and stereo-selective reactions. Since the erythrocytic delta-aminolevulinate dehydratase (delta-ALA-D) activity could be an important indicator of toxicity, this report investigated bis and tris-selenide alkene derivatives effects on blood delta-ALA-D in vitro. To investigate the mechanisms by which these compounds inhibit human blood delta-ALA-D activity, a thiol reducing agent or zinc chloride were used. 1,2-Bis-selenide alkene derivatives 1a (R=4-MeOC(6)H(4)), 1b (R=4-ClC(6)H(4)) and 1c (R=2,4,6-Me(3)C(6)H(2)) did not inhibit human blood delta-ALA-D activity. 1,1,2-Tris-selenide alkene derivative 2a (R=C(6)H(5)) was the most potent delta-ALA-D inhibitor. Compounds 2b (R=4-MeOC(6)H(4)) and 2c (R=4-ClC(6)H(4)) displayed similar inhibitory potency towards delta-ALA-D activity. Dithiothreitol, a hydrophobic SH-reducing agent, was able to restore and to protect delta-ALA-D activity inhibited by tris-selenide alkene derivatives. Conversely, ZnCl(2) did not alter the enzyme inhibition induced by tris-selenide alkene derivatives. From these findings we suggest that 1,1,2-tris-selenide alkene derivatives inhibited delta-ALA-D activity by an interaction with essential sulfhydryl groups for the enzyme activity. 相似文献
99.
100.
Chromatin restricts the accessibility of DNA to regulatory factors; its remodeling over the regulatory regions contributes to the control of gene expression. An increasing number of evidence links defects in chromatin remodeling machinery and cancer. Our aim is to elucidate the role of chromatin structure in the control of the expression of hormone-induced genes in breast cell lines estrogen-dependent or -independent for growth. Mammary tumor growth is controlled by steroid hormones via their nuclear receptor and by growth factors via tyrosine kinase receptors. 50 % of these tumors elude to hormonal control. This limits the anti-estrogen therapy. As a model, we have analyzed in several cell lines the chromatin organization of the regulatory regions of two genes, pS2 that is associated with a good prognostic, and cathepsin D (catD) that is a bad prognostic marker. The expression of the two genes is estrogen-regulated in estrogen-dependent cell line MCF7. In contrast in the hormone-independent cell line MDA MB 231, pS2 is not expressed and catD is constitutively expressed. Within the regulatory regions of pS2 gene, we have localized two regions that undergo a hormone-dependent change in chromatin structure in MCF7 cells but not in MDA MB 231. The lack of chromatin remodeling in MDA MB 231 cells is not due to the absence of expression of the estrogen receptor in the cell line. The expression of pS2 gene can be correlated with chromatin remodeling over the regulatory regions of pS2 gene. In contrast catD regulatory regions did not display hormone-dependent changes in chromatin structure, suggesting that hormone regulation takes place within regions with a constitutively open chromatin structure. 相似文献