Canastra Minas Artisanal Cheese is produced in the Brazilian State of Minas Gerais using raw milk, rennet, and pingo, a natural endogenous starter culture (fermented whey) collected from the previous ...day’s production. Due to the use of raw milk, the product can carry microorganisms that may cause foodborne diseases (FBD), including
Staphylococcus aureus
. Genomic characterization of
S. aureus
is an important tool to assess diversity, virulence, antimicrobial resistance, and the potential for causing food poisoning due to enterotoxin production. This study is aimed at exploring the genomic features of
S. aureus
strains isolated from Canastra Minas Artisanal Cheeses. Multilocus sequence typing (MLST) classified these strains as ST1, ST5, and a new profile ST7849 (assigned to the clonal complex CC97). These strains belonged to four spa types: t008, t127, t359, and t992. We identified antimicrobial resistance genes with phenotypic correlation against methicillin (MRSA) and tetracycline. Virulome analysis revealed genes associated with iron uptake, immune evasion, and potential capacity for adherence and biofilm formation. The toxigenic potential included cyto- and exotoxins genes, and all strains presented the genes that encode for Panton-Valentine toxin and hemolysin, and two strains encoded 4 and 8 Staphylococcal enterotoxin (SE) genes. The results revealed the pathogenic potential of the evaluated
S. aureus
strains circulating in the Canastra region, representing a potential risk to public health. This study also provides useful information to monitor and guide the application of control measures to the artisanal dairy food production chain.
This paper describes the preparation of Sodium Polyphosphates Coacervates (NaPC) through the direct addition of different methanol molar fractions to a sodium polyphosphate solution. The presence of ...methanol reduces the dielectric constant medium and it promotes the coacervate formation. Rheology measurement shows that the NaPC viscosity is dependent on a methanol molar fraction, which is caused by the dielectric constant reduction of the water-methanol mixture. Raman spectra for the lyophilized NaPC show that the symmetric P-Ot stretching mode is more sensitive than the symmetric P-Ob stretching mode, due to the approach of the adjacent polyphosphate chains. The 31P NMR spectra also confirm a decrease in the Q2/Q1 ratio because of the methanol content. Besides, we have obtained transparent soft Glass-Materials to melt NaPC at 800 °C.
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•Sodium Coacervates Polyphosphates (NaPC) were prepared.•Methanol reduces the dielectric constant and it leads to coacervation process.•NaPC can be used as soft Glass-Materials precursors.
The increasing demand for fresh fruits and vegetables and for convenience foods is causing an expansion of the market share for minimally processed vegetables. Among the more common pathogenic ...microorganisms that can be transmitted to humans by these products are Listeria monocytogenes, Escherichia coli O157:H7, and Salmonella. The aim of this study was to evaluate the microbial quality of a selection of minimally processed vegetables. A total of 181 samples of minimally processed leafy salads were collected from retailers in the city of Sao Paulo, Brazil. Counts of total coliforms, fecal coliforms, Enterobacteriaceae, psychrotrophic microorganisms, and Salmonella were conducted for 133 samples. L. monocytogenes was assessed in 181 samples using the BAX System and by plating the enrichment broth onto Palcam and Oxford agars. Suspected Listeria colonies were submitted to classical biochemical tests. Populations of psychrotrophic microorganisms >10(6) CFU/g were found in 51% of the 133 samples, and Enterobacteriaceae populations between 10(5) and 10(6) CFU/g were found in 42% of the samples. Fecal coliform concentrations higher than 10(2) CFU/g (Brazilian standard) were found in 97 (73%) of the samples, and Salmonella was detected in 4 (3%) of the samples. Two of the Salmonella-positive samples had <10(2) CFU/g concentrations of fecal coliforms. L. monocytogenes was detected in only 1 (0.6%) of the 181 samples examined. This positive sample was simultaneously detected by both methods. The other Listeria species identified by plating were L. welshimeri (one sample of curly lettuce) and L. innocua (2 samples of watercress). The results indicate that minimally processed vegetables had poor microbiological quality, and these products could be a vehicle for pathogens such as Salmonella and L. monocytogenes.
Bacteriocins produced by lactic acid bacteria are gaining increased importance due to their activity against undesirable microorganisms in foods. In this study, a concentrated acid extract of a ...culture of Lactobacillus sakei subsp. sakei 2a, a bacteriocinogenic strain isolated from a Brazilian pork product, was purified by cation exchange and reversed-phase chromatographic methods. The amino acid sequences of the active antimicrobial compounds determined by Edman degradation were compared to known protein sequences using the BLAST-P software. Three different antimicrobial compounds were obtained, P1, P2 and P3, and mass spectrometry indicated molecular masses of 4.4, 6.8 and 9.5 kDa, respectively. P1 corresponds to classical sakacin P, P2 is identical to the 30S ribosomal protein S21 of L. sakei subsp. sakei 23 K, and P3 is identical to a histone-like DNA-binding protein HV produced by L. sakei subsp. sakei 23 K. Total genomic DNA was extracted and used as target DNA for PCR amplification of the genes sak, lis and his involved in the synthesis of P1, P2 and P3. The fragments were cloned in pET28b expression vector and the resulting plasmids transformed in E. coli KRX competent cells. The transformants were active against Listeria monocytogenes, indicating that the activity of the classical sakacin P produced by L. sakei 2a can be complemented by other antimicrobial proteins.
Purpose The aim of the present study was to perform a systematic review of the literature on the effect of different insoles on postural balance. Subjects and Methods A systematic review was ...conducted of four databases. The papers retrieved were evaluated based on the following inclusion criteria: 1) design: controlled clinical trial; 2) intervention: insole; 3) outcome: change in static postural balance; and 4) year of publication: 2005 to 2012. Results Twelve controlled trials were found comparing the effects of different insoles on postural balance. The papers had methodological quality scores of 3 or 4 on the PEDro scale. Conclusion Insoles have benefits that favor better postural balance and control.
Rhinobatos percellens, Rhinobatos horkelli and Zapteryx brevirostris, known as guitarfish, are commonly found inshore and caught by trawl nets. Recently, these species have been suffering sharp ...population declines. One of the main impediments to the development of conservation plans is the lack of information related to each species catch. Gathering this information is made more difficult by the fishermen's practice of removing parts of the animals before landing, as well as the morphological similarities among the three species. To address these issues, this work presents multiplex-PCR protocols that were developed to distinguish among these species using their genetic characteristics.
The morphology of the eggs and miracidia of Eurytrema coelomaticum was analyzed. The eggshell presented different composition according to the maturation stage of the egg, as seen by distinct ...birefringence after polarized light microscopic analysis. Detailed morphology of the brownish eggs, measuring 44.97±3.83 (38.67 - 51.40) μm in length and 30.71±2.54 (25.79 -34.47) μm in width, and the different electrondensities of the inner, middle and outer layers of the eggs were determined using light (bright field and DIC) and electronic microscopy (scanning and transmission). The morphometry of the eggs is in accordance to those measures presented in previous studies. The miracidia were observed using light microscopy, inside and outside the egg. It was possible to observe the terebratorium at the anterior end of the body, the ciliated epidermal plates, placed according the formula E=2E₁ + 2E₂, and the interepidermal ridge, but eyespots were not observed. The excretory vesicle was laterally placed in the posterior middle of the body and the germ balls were observed. The miracidium inside the egg was observed by routine techniques, but the miracidium was not well preserved. Thus, the eggs were processed using high pressure-freeze substitution technique and reasonable preservation was achieved. The cilia covering the larval body, with a typical ciliary organization, the terebratorium with folds and the junction of the epidermal ciliated cell with the larval body were seen. For the first time detailed information on the eggs and miracidia of E. coelomaticum is given, which can be the basis for new studies.
Intrauterine growth restriction (IUGR) can induce deleterious changes in the modulatory ability of the vascular endothelium, contributing to an increased risk of developing cardiovascular diseases in ...the long term. However, the mechanisms involved are not fully understood. Emerging evidence has suggested the potential role of endothelial progenitor cells (EPCs) in vascular health and repair. Therefore, we aimed to evaluate the effects of IUGR on vascular reactivity and EPCs derived from the peripheral blood (PB) and bone marrow (BM) in vitro. Pregnant Wistar rats were fed an ad libitum diet (control group) or 50% of the ad libitum diet (restricted group) throughout gestation. We determined vascular reactivity, nitric oxide (NO) concentration, and endothelial nitric oxide synthase (eNOS) protein expression by evaluating the thoracic aorta of adult male offspring from both groups (aged: 19-20 weeks). Moreover, the amount, functional capacity, and senescence of EPCs were assessed in vitro. Our results indicated that IUGR reduced vasodilation via acetylcholine in aorta rings, decreased NO levels, and increased eNOS phosphorylation at Thr495. The amount of EPCs was similar between both groups; however, IUGR decreased the functional capacity of EPCs from the PB and BM. Furthermore, the senescence process was accelerated in BM-derived EPCs from IUGR rats. In summary, our findings demonstrated the deleterious changes in EPCs from IUGR rats, such as reduced EPC function and accelerated senescence in vitro. These findings may contribute towards elucidating the possible mechanisms involved in endothelial dysfunction induced by fetal programming.
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