RESUMO
Rare earth elements (REE) have unique chemical properties, which allow their use as geochemical tracers. In this context, the present study aims to assess the role of Funil Reservoir on REE biogeochemical behavior. We collected water samples upstream of the reservoir (P-01) in the city of Queluz, inside the reservoir (P-02), and downstream of Funil Reservoir (P-03) in the city of Itatiaia, RJ. In the field, physicochemical parameters were measured using a probe (pH, temperature, electrical conductivity, and dissolved oxygen). In the laboratory, water samples were filtered (0.45 µm) and properly packed until chemical analysis. Chlorophyll a concentrations were determined by a spectrophotometric method and suspended particulate matter (SPM) by a gravimetric method. Ionic concentrations were determined by ion chromatography technique and REE concentrations were determined by ICP-MS. Chlorophyll a concentrations were higher in Funil Reservoir. Ionic concentrations in Queluz (P-01) suggest anthropic contamination. The sum of REE in the dissolved fraction ranged from 2.12 to 12.22 µg L-1. A positive anomaly of La in Queluz indicates anthropic contamination. The observed patterns indicate that Funil Reservoir acts as a biogeochemical barrier, modifying the fluvial transport of REE. Nonetheless, another factor that probably influences REE behavior is the algal bloom that occurs in reservoirs during the rainy season. The seasonal behavior of algae can influence REE biogeochemistry through the incorporation and release of trace metals.
Assuntos
Metais Terras Raras , Poluentes Químicos da Água , Clorofila A/análise , Brasil , Monitoramento Ambiental , Metais Terras Raras/análise , Água/análise , Poluentes Químicos da Água/análiseRESUMO
Cheeses are able to serve as suitable matrices for supplying probiotics to consumers, enabling appropriate conditions for bacteria to survive gastric transit and reach the gut, where they are assumed to promote beneficial processes. The present study aimed to evaluate the microbiological, immunological, and histological changes in the gut of Salmonella Enteritidis-challenged rats fed goat cheese supplemented with the probiotic strain Lactobacillus rhamnosus EM1107. Thirty male albino Wistar rats were randomly distributed into 5 experimental groups with 6 animals each: negative (NC) and positive (PtC) control groups, control goat cheese (CCh), goat cheese added with L. rhamnosus EM1107 (LrCh), and L. rhamnosus EM1107 only (EM1107). All animals, except NC group were challenged with Salmonella Enteritidis (109 cfu in 1 mL of saline through oral gavage). Microbial composition was assessed with high-throughput 16S rRNA sequencing by means of Illumina MiSeq (Illumina, San Diego, CA). Nuclear factor kappa B (NF-κB) from the animal cecum tissue was determined by real-time PCR and interleukins (TNF-α, IL-1ß, IL-10, and IFN-γ) by means of ELISA. Myeloperoxidase and malondialdehyde levels were determined biochemically. The administration of the L. rhamnosus EM1107 probiotic strain, either as a pure culture or added to a cheese matrix, was able to reduce Salmonella colonization in the intestinal lumen and lessen tissue damage compared with rats from PtC group. In addition, the use of cheese for the probiotic strain delivery (LrCh) was associated with a marked shift in the gut microbiota composition toward the increase of beneficial organisms such as Blautia and Lactobacillus and a reduction in NF-κB expression. These findings support our hypothesis that cheeses might be explored as functional matrices for the efficacious delivery of probiotic strains to consumers.
Assuntos
Queijo/microbiologia , Cabras , Intestinos/imunologia , Intestinos/microbiologia , Lacticaseibacillus rhamnosus/metabolismo , Probióticos , Salmonella enteritidis/imunologia , Animais , Ceco/metabolismo , Ceco/microbiologia , Microbioma Gastrointestinal , Masculino , RNA Ribossômico 16S , Ratos , Ratos WistarRESUMO
AIMS: To investigate the effect of heme, cobalt-protoporphyrin IX and tin-protoporphyrin IX (CoPPIX and SnPPIX), macrocyclic structures composed by a tetrapyrrole ring with a central metallic ion, on Dengue Virus (DENV) and Yellow Fever Virus (YFV) infection. METHODS AND RESULTS: Treatment of HepG2 cells with heme, CoPPIX and SnPPIX after DENV infection reduced infectious particles without affecting viral RNA contents in infected cells. The reduction of viral load occurs only with the direct contact of DENV with porphyrins, suggesting a direct effect on viral particles. Previously incubation of DENV and YFV with heme, CoPPIX and SnPPIX resulted in viral particles inactivation in a dose-dependent manner. Biliverdin, a noncyclical porphyrin, was unable to inactivate the viruses tested. Infection of HepG2 cells with porphyrin-pretreated DENV2 results in a reduced or abolished viral protein synthesis, RNA replication and cell death. Treatment of HepG2 or THP-1 cell lineage with heme or CoPPIX after DENV infection with a very low MOI resulted in a decreased DENV replication and protection from death. CONCLUSIONS: Heme, CoPPIX and SnPPIX possess a marked ability to inactivate DENV and YFV, impairing its ability to infect and induce cytopathic effects on target cells. SIGNIFICANCE AND IMPACT OF THE STUDY: These results open the possibility of therapeutic application of porphyrins or their use as models to design new antiviral drugs against DENV and YFV.
Assuntos
Antivirais/farmacologia , Vírus da Dengue/efeitos dos fármacos , Dengue/virologia , Heme/farmacologia , Metaloporfirinas/farmacologia , Protoporfirinas/farmacologia , Febre Amarela/virologia , Vírus da Febre Amarela/efeitos dos fármacos , Antivirais/química , Dengue/tratamento farmacológico , Vírus da Dengue/genética , Vírus da Dengue/fisiologia , Heme/química , Humanos , Metaloporfirinas/química , Protoporfirinas/química , RNA Viral/genética , Inativação de Vírus/efeitos dos fármacos , Febre Amarela/tratamento farmacológico , Vírus da Febre Amarela/genética , Vírus da Febre Amarela/fisiologiaRESUMO
AIM: To assess the immediate influence of dentine bonding systems (DBS) associated with 2% chlorhexidine digluconate (CHX) on glass-fibre post-bond strength to root dentine, in terms of coronal, middle and apical thirds. METHODOLOGY: Sixty bovine roots were root filled and randomly assigned to 1 of 6 groups (n = 10): SBMP (3-step etch-and-rinse system, Scotchbond Multi-Purpose), SB (2-step etch-and-rinse system, Single Bond 2), SE (2-step self-etching system, Clearfil SE Bond) and SBMP-CHX, SB-CHX and SE-CHX, respectively, associated with CHX. For all groups, a glass-fibre post was luted with a dual-cure resin cement, RelyX ARC. After 7-day storage, specimens were subjected to the push-out test. Failure modes were analysed under optical microscopy (40x). Bond strength values were statistically analysed by two-way anova and Bonferroni tests (P < 0.05). RESULTS: The effect of DBS was significant (P < 0.05), and SE reached higher bond strength in comparison with the other DBS tested. CHX association did not show improvement with any DBS (P > 0.05); rather, it negatively affected SE, which was detected for all thirds. There was no difference between thirds (P > 0.05), except for the SE-CHX, which presented lower values for the apical third (P < 0.05). Adhesive cement/dentine adhesive failure was predominant for all groups. CHX did not influence the failure mode for any DBS (P > 0.05). CONCLUSIONS: The performance of the dentine bonding systems was material dependent. CHX did not improve immediate bond strength; however, CHX negatively affected the bond strength of the self-etching system, especially in the third apical.
Assuntos
Anti-Infecciosos Locais/química , Clorexidina/análogos & derivados , Colagem Dentária , Materiais Dentários/química , Cavidade Pulpar/ultraestrutura , Dentina/ultraestrutura , Vidro/química , Técnica para Retentor Intrarradicular/instrumentação , Condicionamento Ácido do Dente/métodos , Animais , Bis-Fenol A-Glicidil Metacrilato/química , Bovinos , Clorexidina/química , Cimentos Dentários/química , Análise do Estresse Dentário/instrumentação , Adesivos Dentinários/química , Polietilenoglicóis/química , Ácidos Polimetacrílicos/química , Distribuição Aleatória , Cimentos de Resina/química , Autocura de Resinas Dentárias , Estresse Mecânico , Fatores de Tempo , Ápice Dentário/ultraestruturaRESUMO
ABSTRACT To evaluate the population fluctuation of Mezium americanum (Coleoptera: Ptinidae) two monitoring methods were used: the tube trap and the sandwich trap. The experiment took place in the period from April 2002 to March of 2003, in an aviary of the Conjunto Agrotécnico Visconde da Graça (CAVG), located in Pelotas, Rio Grande do Sul, Brazil. In that period 367 specimens of M. americanum were captured, the period of greatest occurrence being in the month of February (121), when the monthly mean temperature was 24.7º C, while the least occurrence was in the months of July and September (01) with monthly mean temperature around 13.8º C. The coleopteron was absent in only 3 of the 12 months of collection, demonstrating the potential importance of this species in aviaries.
RESUMO Para avaliar a flutuação populacional de Mezium americanum (Coleoptera: Ptinidae) foram utilizados dois métodos de monitoramento, armadilha do tipo tubo e do tipo sanduíche. O experimento foi realizado no período de abril de 2002 a março de 2003, em aviário do Conjunto Agrotécnico Visconde da Graça (CAVG), localizado em Pelotas, Rio Grande do Sul, Brasil. Nesse período foram capturados 367 exemplares de M. americanum, sendo o período de maior ocorrência no mês de fevereiro (121), quando a temperatura média mensal foi de 24,7º C e a menor ocorrência se deu nos meses de julho e setembro (1), com temperatura média mensal em torno de 13,8º C. O coleóptero não esteve presente em apenas três dos 12 meses de coleta, demonstrando a potencial importância desta espécie em aviários.
RESUMO
Os autores estudaram na Enfermaria 34 da Santa Casa de Misericordia de Porto Alegre durante o periodo de 1o. de setembro de 1980 a 31 de agosto de 1981, a incidencia de infeccao hospitalar e comunitaria; os principais agentes destas infeccoes: a localizacao dos mesmos e a sensibilidade bacteriana aos principais antibioticos usados