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961.
Eduardo Massad Annelies Wilder-Smith Raphael Ximenes Marcos Amaku Luis Fernandez Lopez Francisco Antonio Bezerra Coutinho Giovanini Evelim Coelho Jarbas Barbosa da Silva Jr Claudio José Struchiner Marcelo Nascimento Burattini 《Memórias do Instituto Oswaldo Cruz》2014,109(3):394-397
Brazil will host the FIFA World Cup™, the biggest single-event competition in the
world, from June 12-July 13 2014 in 12 cities. This event will draw an estimated
600,000 international visitors. Brazil is endemic for dengue. Hence, attendees of the
2014 event are theoretically at risk for dengue. We calculated the risk of dengue
acquisition to non-immune international travellers to Brazil, depending on the
football match schedules, considering locations and dates of such matches for June
and July 2014. We estimated the average per-capita risk and expected
number of dengue cases for each host-city and each game schedule chosen based on
reported dengue cases to the Brazilian Ministry of Health for the period between
2010-2013. On the average, the expected number of cases among the 600,000 foreigner
tourists during the World Cup is 33, varying from 3-59. Such risk estimates will not
only benefit individual travellers for adequate pre-travel preparations, but also
provide valuable information for public health professionals and policy makers
worldwide. Furthermore, estimates of dengue cases in international travellers during
the World Cup can help to anticipate the theoretical risk for exportation of dengue
into currently non-infected areas. 相似文献
962.
Fernanda Aparecida Nieri-Bastos Marcos Gomes Lopes Paulo Henrique Duarte Can?ado Giselle Ayres Razera Rossa Jo?o Luiz Horácio Faccini Solange Maria Gennari Marcelo Bahia Labruna 《Memórias do Instituto Oswaldo Cruz》2014,109(2):259-261
Adult ticks of the species Amblyomma parvum were collected from the
vegetation in the Pantanal biome (state of Mato Grosso do Sul) and from horses in the
Cerrado biome (state of Piauí) in Brazil. The ticks were
individually tested for rickettsial infection via polymerase chain reaction (PCR)
targeting three rickettsial genes, gltA, ompA and
ompB. Overall, 63.5% (40/63) and 66.7% (2/3) of A.
parvum ticks from Pantanal and Cerrado, respectively, contained
rickettsial DNA, which were all confirmed by DNA sequencing to be 100% identical to
the corresponding fragments of the gltA, ompA and
ompB genes of Candidatus Rickettsia andeanae.
This report is the first to describe Ca. R. andeanae in Brazil. 相似文献
963.
Luiza Pinheiro Carla Ivo Brito Valéria Cataneli Pereira Adilson de Oliveira Carlos Henrique Camargo Maria de Lourdes Ribeiro de Souza da Cunha 《Memórias do Instituto Oswaldo Cruz》2014,109(7):871-878
This study aimed to correlate the presence of ica genes, biofilm
formation and antimicrobial resistance in 107 strains of Staphylococcus
epidermidis isolated from blood cultures. The isolates were analysed to
determine their methicillin resistance, staphylococcal cassette chromosome
mec (SCCmec) type, ica genes
and biofilm formation and the vancomycin minimum inhibitory concentration (MIC) was
measured for isolates and subpopulations growing on vancomycin screen agar. The
mecA gene was detected in 81.3% of the S.
epidermidis isolated and 48.2% carried SCCmec type III.
The complete icaADBC operon was observed in 38.3% of the isolates;
of these, 58.5% produced a biofilm. Furthermore, 47.7% of the isolates grew on
vancomycin screen agar, with an increase in the MIC in 75.9% of the isolates.
Determination of the MIC of subpopulations revealed that 64.7% had an MIC ≥ 4 μg
mL-1, including 15.7% with an MIC of 8 μg mL-1 and 2% with
an MIC of 16 μg mL-1. The presence of the icaADBC operon,
biofilm production and reduced susceptibility to vancomycin were associated with
methicillin resistance. This study reveals a high level of methicillin resistance,
biofilm formation and reduced susceptibility to vancomycin in subpopulations of
S. epidermidis. These findings may explain the selection of
multidrug-resistant isolates in hospital settings and the consequent failure of
antimicrobial treatment. 相似文献
964.
Maricela Robles-Murguia Nicholas Bloedow Leigh Murray Marcelo Ramalho-Ortig?o 《Memórias do Instituto Oswaldo Cruz》2014,109(8):1064-1069
In sandflies, the absence of the peritrophic matrix (PM) affects the rate of blood
digestion. Also, the kinetics of PM secretion varies according to species. We
previously characterised PpChit1, a midgut-specific chitinase secreted in
Phlebotomus papatasi (PPIS) that is involved in the maturation of the PM
and showed that antibodies against PpChit1 reduce the chitinolytic activity in the
midgut of several sandfly species. Here, sandflies were fed on red blood cells
reconstituted with naïve or anti-PpChit1 sera and assessed for fitness parameters
that included blood digestion, oviposition onset, number of eggs laid, egg bouts,
average number of eggs per bout and survival. In PPIS, anti-PpChit1 led to a one-day
delay in the onset of egg laying, with flies surviving three days longer compared to
the control group. Anti-PpChit1 also had a negative effect on overall ability of
flies to lay eggs, as several gravid females from all three species were unable to
lay any eggs despite having lived longer than control flies. Whereas the longer
survival might be associated with improved haeme scavenging ability by the PM, the
inability of females to lay eggs is possibly linked to changes in PM permeability
affecting nutrient absorption. 相似文献
965.
Henrique D. de Menezes Gabriela B. Rodrigues Simone de Pádua Teixeira Nelson S. Massola Jr. Luciano Bachmann Mark Wainwright Gilberto U. L. Braga 《Applied and environmental microbiology》2014,80(5):1623-1632
The increasing tolerance to currently used fungicides in both clinical and agricultural areas is of great concern. The nonconventional light-based approach of antimicrobial photodynamic treatment (APDT) is a promising alternative to conventional fungicides. We evaluated the effects of APDT with four phenothiazinium derivatives (methylene blue [MB], new methylene blue N [NMBN], toluidine blue O [TBO], and the novel pentacyclic phenothiazinium photosensitizer [PS] S137) on conidia of three fungal species (Colletotrichum acutatum, Colletotrichum gloeosporioides, and Aspergillus nidulans). The efficacy of APDT with each PS was determined, initially, based on photosensitizer MICs. Additionally, the effects of APDT with two selected PSs (NMBN and S137) on survival of conidia were evaluated. The subcellular localization of the PS in C. acutatum conidia was determined. The effects of photodynamic treatments on leaves of the plant host Citrus sinensis were also investigated. APDT with S137 showed the lowest MIC. MICs for S137 were 5 μM for the three fungal species when a fluence of 25 J cm−2 was used. APDT with NMBN (50 μM) and S137 (10 μM) resulted in a reduction in the survival of the conidia of all species of approximately 5 logs with fluences of ≥15 J cm−2. Washing of the conidia before light exposure did not prevent photodynamic inactivation. Both NMBN and S137 accumulated in cytoplasmic structures, such as lipid bodies, of C. acutatum conidia. No damage to orange tree leaves was observed after APDT. 相似文献
966.
Geneviève LeBel Katy Vaillancourt Michel Frenette Marcelo Gottschalk Daniel Grenier 《Applied and environmental microbiology》2014,80(17):5484-5492
Streptococcus suis serotype 2 is known to cause severe infections (meningitis, endocarditis, and septicemia) in pigs and is considered an emerging zoonotic agent. Antibiotics have long been used in the swine industry for disease treatment/prevention and growth promoters. This pattern of utilization resulted in the spread of antibiotic resistance in S. suis worldwide. Interestingly, pigs may harbor S. suis in their tonsils without developing diseases, while North American strains belonging to the sequence type 28 (ST28) are nonvirulent in animal models. Consequently, the aim of this study was to purify and characterize a bacteriocin produced by a nonvirulent strain of S. suis serotype 2, with a view to a potential therapeutic and preventive application. S. suis 90-1330 belonging to ST28 and previously shown to be nonvirulent in an animal model exhibited antibacterial activity toward all S. suis pathogenic isolates tested. The bacteriocin produced by this strain was purified to homogeneity by cationic exchange and reversed-phase fast protein liquid chromatography. Given its properties (molecular mass of <4 kDa, heat, pH and protease stability, and the presence of modified amino acids), the bacteriocin, named suicin 90-1330, belongs to the lantibiotic class. Using a DNA-binding fluorophore, the bacteriocin was found to possess a membrane permeabilization activity. When tested on other swine pathogens, the suicin showed activity against Staphylococcus hyicus and Staphylococcus aureus, whereas it was inactive against all Gram-negative bacteria tested. Amino acid sequencing of the purified bacteriocin showed homology (90.9% identity) with nisin U produced by Streptococcus uberis. The putative gene cluster involved in suicin production was amplified by PCR and sequence analysis revealed the presence of 11 open reading frames, including the structural gene and those required for the modification of amino acids, export, regulation, and immunity. Further studies will evaluate the ability of suicin 90-1330 or the producing strain to prevent experimental S. suis infections in pigs. 相似文献
967.
968.
Vanessa Faria Cortes Izabela Matos Ribeiro Hector Barrabin Marcelo Alves-Ferreira Carlos Frederico Leite Fontes 《Archives of biochemistry and biophysics》2011,(1):75
FXYD2 is a regulatory peptide associated with the α-subunit of the kidney Na,K-ATPase. FXYD2 can be phosphorylated by PKA, and its phosphorylation activates Na,K-ATPase. Here we show that FXYD2 is phosphorylated by PKC (PKC-FXYD2-P), by PKA (PKA-FXYD2-P) or by PKA and PKC simultaneously (FXYD2-P2) modulating both the erythrocyte Na,K-ATPase and the plasma membrane Ca2+-ATPase (PMCA). In erythrocyte ghosts, the addition of PKA-FXYD2-P activated Na,K-ATPase by 80%, while non-phosphorylated FXYD2 (np) activated only 55%. The addition of np FXYD2 did not affect PMCA basal activity, but FXYD2-P2 increased the basal PMCA activity by up to 200%. Calmodulin-activated PMCA activity was increased by np FXYD2 (3-fold) or FXYD2-P2 (2.5-fold). However, PKC-FXYD2-P increased PMCA activity only by 50%. In contrast, when PMCA was treated with PKA-FXYD2-P, the ATPase activity was inhibited by 50%. The effect of all forms of FXYD2-P on calcium uptake from PMCA resembled the pattern observed in ATP hydrolysis. Our results suggest that the FXYD2 anchoring site could be conserved among the P-ATPase family permitting cross regulation. The effects of FXYD2 on calcium uptake and calcium-stimulated ATP hydrolysis suggest a novel role for FXYD2 on PMCA. 相似文献
969.
Binker MG Binker-Cosen AA Gaisano HY de Cosen RH Cosen-Binker LI 《Biochemical and biophysical research communications》2011,(1):140-145
Post-translational acetylation is an important molecular regulatory mechanism affecting the biological activity of proteins. Polypeptide GalNAc transferases (ppGalNAc-Ts) are a family of enzymes that catalyze initiation of mucin-type O-glycosylation. All ppGalNAc-Ts in mammals are type II transmembrane proteins having a Golgi lumenal region that contains a catalytic domain with glycosyltransferase activity, and a C-terminal R-type (“ricin-like”) lectin domain. We investigated the effect of acetylation on catalytic activity of glycosyltransferase, and on fine carbohydrate-binding specificity of the R-type lectin domain of ppGalNAc-T2. Acetylation effect on ppGalNAc-T2 biological activity in vitro was studied using a purified human recombinant ppGalNAc-T2. Mass spectrometric analysis of acetylated ppGalNAc-T2 revealed seven acetylated amino acids (K103, S109, K111, K363, S373, K521, and S529); the first five are located in the catalytic domain. Specific glycosyltransferase activity of ppGalNAc-T2 was reduced 95% by acetylation. The last two amino acids, K521 and S529, are located in the lectin domain, and their acetylation results in alteration of the carbohydrate-binding ability of ppGalNAc-T2. Direct binding assays showed that acetylation of ppGalNAc-T2 enhances the recognition to αGalNAc residue of MUC1αGalNAc, while competitive assays showed that acetylation modifies the fine GalNAc-binding form of the lectin domain. Taken together, these findings clearly indicate that biological activity (catalytic capacity and glycan-binding ability) of ppGalNAc-T2 is regulated by acetylation. 相似文献
970.
Bezerra EH Rocha BA Nagano CS Bezerra Gde A Moura TR Bezerra MJ Benevides RG Sampaio AH Assreuy AM Delatorre P Cavada BS 《Biochemical and biophysical research communications》2011,(4):566-570
Diocleinae lectins are highly homologous in their primary structure which features metal binding sites and a carbohydrate recognition domain (CRD). Differences in the biological activity of legume lectins have been widely investigated using hemagglutination inhibition assays, isothermal titration microcalorimetry and co-crystallization with mono- and oligosaccharides. Here we report a new lectin crystal structure (ConBr) extracted from seeds of Canavalia brasiliensis, predict dimannoside binding by docking, identify the α-aminobutyric acid (Abu) binding pocket and compare the CRD of ConBr to that of homologous lectins. Based on the hypothesis that the carbohydrate affinity of lectins depends on CRD configuration, the relationship between tridimensional structure and endothelial NO synthase activation was used to clarify differences in biological activity. Our study established a correlation between the position of CRD amino acid side chains and the stimulation of NO release from endothelium. 相似文献