RAW TROPICAL OYSTERS AS VEHICLES FOR MULTIDRUG-RESISTANT Vibrio parahaemolyticus

The following study aimed to determine the antimicrobial susceptibility profile of Vibrio parahaemolyticus strains from fresh and frozen oysters Crassostrea rhizophorae sold in Fortaleza-Brazil. An antibiogram was performed on 87 isolates using nine antibiotics: gentamicin (Gen 10 µg), ampicillin (Amp 10 µg), penicillin G (Pen 10U), ciprofloxacin (Cip 5 µg), chloramphenicol (Chl 30 µg), nalidixic acid (Nal 30 µg), tetracycline (Tet 30 µg), vancomycin (Van 30 µg) and erythromycin (Ery 15 µg). All strains were resistant to at least one antibiotic, and 85 (97.7%) were multi-resistant, with predominance of the Van+ Pen+Amp resistance profile (n = 46). Plasmid resistance to Pen, Amp and Ery was detected. Thus, the risk that raw oyster consumption poses to the health of consumers is highlighted, due to the fact that these bivalves may host antibacterial-resistant microorganisms.

Biomass accumulation, photochemical efficiency of photosystem II, nutrient contents and nitrate reductase activity in young rosewood plants (Aniba rosaeodora Ducke) submitted to different NO3-:NH4+ ratios

The rosewood (Aniba rosaeodora Ducke) is a native tree species of Amazon rainforest growing naturally in acidic forest soils with reduced redox potential. However, this species can also been found growing in forest gaps containing oxide soils. Variations in the forms of mineral nitrogen (NO3- or NH4+) may be predicted in these different edaphic conditions. Considering that possibility, an experiment was carried out to analyze the effects of different NO3-:NH4+ ratios on the growth performance, mineral composition, chloroplastid pigment contents, photochemical efficiency photosystem II (PSII), and nitrate redutase activity (RN, E.C.1.6.6.1) on A. rosaeodora seedlings. Nine-month-old seedlings were grown in pots with a washed sand capacity of 7.5 kg and submitted to different NO3-:NH4+ ratios (T1 = 0:100%, T2 = 25:75%, T3 = 50:50%, T4 = 75:25%, and T5 = 100:0%). The lowest relative growth rate was observed when the NO3-:NH4+ ratio was equal to 0:100%. In general, high concentrations of NO3- rather than NH4+ favored a greater nutrient accumulation in different parts of the plant. For the chloroplastid pigment, the highest Chl a, Chl b, Chl tot, Chl a/b and Chl tot/Cx+c contents were found in the treatment with 75:25% of NO3-:NH4+, and for Chl b and Cx+c it was observed no difference. In addition, there was a higher photochemical efficiency of PSII (Fv/Fm) when high NO3- concentrations were used. A linear and positive response for the nitrate reductase activity was recorded when the nitrate content increased on the culture substrate. Our results suggest that A. rosaeodora seedlings have a better growth performance when the NO3- concentrations in the culture substrate were higher than the NH4+ concentrations.

Resistance of Plamodium falciparum to Antimalarial Drugs in Zaragoza (Antioquia, Colombia), 1998

Plasmodium falciparum sensitivity to chloroquine (CHL), amodiaquine (AMO) and sulfadoxine/pyrimethamine (SDX/PYR) was assessed in vivo and in vitro in a representative sample from the population of Zaragoza in El Bajo Cauca region (Antioquia-Colombia). There were 94 patients with P. falciparum evaluated. For the in vivo test the patients were followed by clinical examination and microscopy, during 7 days. The in vitro test was performed following the recommendations of the World Health Organization. The in vivo prevalence of resistance to CHL was 67%, to AMO 3% and to SDX/PYR 9%. The in vitro test showed sensitivity to all antimalarials evaluated. Concordance for CHL between the in vivo and in vitro tests was 33%. For AMO and SDX/PYR, the concordance was 100%. We conclude that a high percentage of patients are resistant to CHL (in vivo). A high rate of intestinal parasitism might explain in part, the differences observed between the in vivo and the in vitro results. Therefore, new policies and treatment regimens should be proposed for the treatment of the infection in the region. Nationwide studies assessing the degree of resistance are needed.

Toxoplasma gondii infection induces lipid metabolism alterations in the murine host

Host lipids have been implicated in the pathogenesis of Toxoplasma gondiiinfection. To determine if Toxoplasmainfection influences the lipid status in the normal host, we assessed serum lipids of Swiss-Webster mice during infection with the BGD-1 strain (type-2) at a series of time points. Mice were bled at days zero and 42 post-infection, and subgroups were additionally bled on alternating weeks (model 1), or sacrificed at days zero, 14 and 42 (model 2) for the measurement of total cholesterol (Chl), high density lipoproteins (HDL), low density lipoproteins (LDL) and triglycerides and adiponectin. At day 42, brains were harvested for cyst enumeration. A significant decrease (p = 0.02) in HDL and total Chl was first noted in infected vs. control mice at day 14 and persisted to day 42 (p = 0.013). Conversely, LDL was unaltered until day 42, when it increased (p = 0.043). Serum LDL levels at day 42 correlated only with cyst counts of above 300 (found in 44% mice), while the change in HDL between days zero and 42 correlated with both the overall mean cyst count (p = 0.041) and cyst counts above 300 (p = 0.044). Calculated per cyst, this decrease in HDL in individual animals ranged from 0.1-17 µmol/L, with a mean of 2.43 ± 4.14 µmol/L. Serum adiponectin levels remained similar between infected and control mice throughout the experiment.

Avaliação de furanocumarinas como inibidores da fotossíntese através de ensaios de fluorescência da clorofila a

The evaluations of Chorophyll a fluorescence emitted by superior plants carry structural information and photosynthetic apparatus function. Quantitative analysis apparatus of fluorescence kinetic were measured by energy flows (ABS), (TR), (ET) and (DI), known as phenomenological phenomena of OJIP test. Four furocoumarins were isolated from Ruta graveolens (Rutaceae), and chorophyll a (Chl a) fluorescence assays were performed with these compounds to evaluate the photosynthesis inhibition potential. This test was realized in spinach`s leaf discs and in Lolium perenne leaves. The results indicated the herbicide potential mainly for bergapten and chalepin.

Chloroplastid pigment contents and chlorophyll a fluorescence in Amazonian tropical three species

Plants react to changes in light and hydrological conditions in terms of quantity and composition of chloroplastidic pigments, which affects the photosynthetic properties and consequently the accumulation of plant biomass. Thus, the chloroplastidic pigment concentration and chlorophyll a fluorescence of three Amazonian species (Bertholletia excelsa, Carapa guianensis e Dipteryx odorata) were investigated in sun and shade leaves form the tree crown collected during two distinct periods of precipitation (dry and rainy seasons). Pigment contents were determined by spectrophotometry and fluorescence variables were determined using a portable fluorometer. The results demonstrated that the species showed high concentrations of Chl a, Chl b e Chl total during the wet season in relation to the dry season, especially in shade leaves. A higher concentration of carotenoids was found in B. excelsa, when compared with leaves of C. guianensis and D. odorata. In leaves of B. excelsa and D. odorata no significant difference was found in relation to the photochemistry of photosystem II (Fv/Fm) between the wet and dry seasons. In conclusion, the three species react differently to variations in the light and precipitation conditions regarding light capture, aspects that might be considered in the management of forest plantations.

Resistência antimicrobiana de Pseudomonas aeruginosa isolados de pescado e de cortes e de miúdos de frango

Pseudomonas aeruginosa isolados de peixes de água doce e de frangos foram submetidos ao teste de suscetibilidade aos antimicrobianos utilizando quatorze drogas, com o objetivo de determinar e confrontar os padrões de suscetibilidade deste microrganismo. As cepas oriundas de peixes pertenciam à coleção do Laboratório de Bacterioses/IV/UFRRJ. Para o isolamento das cepas, foram selecionados miúdos (fígado) e cortes (coxa e sobrecoxa) de frangos adquiridos em estabelecimentos comerciais no município do Rio de Janeiro. A metodologia de isolamento incluiu o enriquecimento em água peptonada, seguido de semeadura em Agar EMB e Agar GSP. Para as cepas oriundas de peixes, procedeu-se à reativação em água peptonada, seguida de reisolamento em Agar EMB. Colônias sugestivas foram transferidas para Agar TSI e LIA para avaliação das características metabólicas. A capacidade de produção de pigmento verde-azulado foi avaliada em Agar Mueller-Hinton e a da enzima citocromo-oxidase, em Agar Nutriente. O teste de suscetibilidade a antimicrobianos realizado nas 63 cepas revelou maiores percentuais de resistência para NAL e NIT (96,8%), TCY (93,6%), AMC (92,1%), CHL (90,5%) e SXT (85,7%), destacando-se a multirresistência dos isolados. A totalidade das cepas oriundas de frangos apresentou sensibilidade a CAZ e IPM e nos isolados de peixes a ATM, CAZ, IPM e AMK.