Adjunctive Rifampicin Increases Antibiotic Efficacy in Group A Streptococcal Tissue Infection Models.

Biofilm has recently been highlighted as a complicating feature of necrotizing soft tissue infections (NSTI) caused by Streptococcus pyogenes (i.e., group A Streptococcus [GAS]) contributing to a persistence of bacteria in tissue despite prolonged antibiotic therapy. Here, we assessed the standard treatment of benzylpenicillin and clindamycin with or without rifampin in a tissue-like setting. Antibiotic efficacy was evaluated by CFU determination in a human organotypic skin model infected for 24 or 48 h with GAS strains isolated from NSTI patients. Antibiotic effect was also evaluated by microcalorimetric metabolic assessment in in vitro infections of cellular monolayers providing continuous measurements over time. Adjunctive rifampin resulted in enhanced antibiotic efficacy of bacterial clearance in an organotypic skin tissue model, 97.5% versus 93.9% (P = 0.006). Through microcalorimetric measurements, adjunctive rifampin resulted in decreased metabolic activity and extended lag phase for all clinical GAS strains tested (P < 0.05). In addition, a case report is presented of adjunctive rifampin treatment in an NSTI case with persistent GAS tissue infection. The findings of this study demonstrate that adjunctive rifampin enhances clearance of GAS biofilm in an in vitro tissue infection model.

Single nucleotide polymorphism in the neuroplastin locus associates with cortical thickness and intellectual ability in adolescents.

Despite the recognition that cortical thickness is heritable and correlates with intellectual ability in children and adolescents, the genes contributing to individual differences in these traits remain unknown. We conducted a large-scale association study in 1583 adolescents to identify genes affecting cortical thickness. Single-nucleotide polymorphisms (SNPs; n=54,837) within genes whose expression changed between stages of growth and differentiation of a human neural stem cell line were selected for association analyses with average cortical thickness. We identified a variant, rs7171755, associating with thinner cortex in the left hemisphere (P=1.12 × 10(-)(7)), particularly in the frontal and temporal lobes. Localized effects of this SNP on cortical thickness differently affected verbal and nonverbal intellectual abilities. The rs7171755 polymorphism acted in cis to affect expression in the human brain of the synaptic cell adhesion glycoprotein-encoding gene NPTN. We also found that cortical thickness and NPTN expression were on average higher in the right hemisphere, suggesting that asymmetric NPTN expression may render the left hemisphere more sensitive to the effects of NPTN mutations, accounting for the lateralized effect of rs7171755 found in our study. Altogether, our findings support a potential role for regional synaptic dysfunctions in forms of intellectual deficits.

Desmoplastic astrocytoma: new insights into its clinical profile, diagnosis, and treatment.

BACKGROUND: Desmoplastic astrocytoma (DA) is a rare intracranial tumor which usually affects pediatric patients. The aim of this study is to describe the clinical features and management of DA based on a joint analysis of the cases reported in the scientific literature. MATERIAL AND METHODS: A thorough review was carried out, gathering those pathologically proven DAs reported since the first description of this entity. Two new own cases were included in order to illustrate this review. Epidemiological, clinical, radiological, therapeutic, and follow-up data were analyzed with the software SPSS version 20. RESULTS: A total of 52 DAs were recorded. Most cases occurred in the first 2 years of life, although older patients were also reported. Patients mainly presented symptoms and signs of elevated intracranial pressure. According to their radiological features, we were able to classify DAs in four main groups, with distinct differential diagnosis and prognosis. After treatment, 14.2 % of patients presented persistent neurological impairment and the mortality rate was close to 10 %. CONCLUSION: DAs can be diagnosed at any age from birth to adolescence. These neoplasms can show up a wider range of radiological morphologies than previously thought. Surgery represents the treatment of choice for DAs, although chemotherapy can also be useful in the setting of recurrence or progression of the disease. Those DAs lacking classic radiological features, especially type 4 tumors, were linked with a poorer clinical outcome.

Incidence of bacteria of public health interest carried by cockroaches in different food-related environments.

The aim of this study was to determine the incidence of bacteria of public health interest transmitted by cockroaches in different food-related environments. From April to November, cockroaches were trapped in 11 buildings in different urban areas of Western Andalusia (Spain): three hotels, four grocery stores, a catering establishment, a food-industry plant, a health center, and a care home. The presence of a number of bacterial species, including Salmonella, in these food-related environments was confirmed; these species included microorganisms listed in European Union regulations, such as Salmonella spp., Enterobacter sakazakii (Cronobacter spp.), and Escherichia coli. A wide variety of species were isolated, some belonging to different genera that have a significant impact on public health and hygiene, such as Enterobacter and Klebsiella. To ensure adequate elimination of these microorganisms in food-related environments, the control of vectors such as Blattella germanica, Periplaneta americana, and Blatta orientalis, together with a thorough review of hygiene strategies, appears to be fundamental. It is clearly essential to compare the results of hygiene regulations implemented in food-related environments.

Analysis of the Population Dynamics of Whitefly (Bemisia tabaci [Hemiptera: Aleyrodidae]) Under Greenhouse Conditions.

Whiteflies (Bemisia tabaci) represent an insect pest in horticulture. It serves as a vector for transmitting phytopathogens that inhibit the correct development of plants, affecting crop performance. In this research, whitefly population model was proposed to provide a tool that predicts the pest spread within a crop under greenhouse conditions. The analysis, calibration, and validation of the models, based on logistic functions, were implemented for the three stages (egg, nymph, and adult) of the life cycle of this organism. Temperature (°C), relative humidity (%), initial population (number/cm2), and Growing Degree-Day (GDD) were considered as input variables to describe each development stage. The statistical analysis for the model validation included the coefficient of determination (R2), the percentage standard error of prediction (%SEP), the average relative variance (AVR), and the efficiency coefficient (E). The first period for calibration consisted of 43 d (204.3 GDD), and the second period for validation consisted of 36 d (171.1 GDD). The model efficiently predicts the population growth for the egg, nymph, and adult stages since the values of R2 were 0.9856, 0.9918, and 0.9436, and the values of %SEP were 12.4, 11.9, and 75.1% for the egg, nymph, and adult stages, respectively. Moreover, the validation model obtained an R2 of 0.9287 for the egg stage, 0.9645 for the nymph stage, and 0.9884 for the adult stage. Meanwhile, the values of %SEP were 10.38, 16.89, and 32.59% for the egg, nymph, and adult stages, respectively. In both cases, the values suggest an adequate fit for the model.

Comparison between the Vitek Immunodiagnostic Assay System and PCR for the detection of pathogenic microorganisms in an experimental dry sausage during its curing process.

The comparison between the Vitek Immunodiagnostic Assay System (VIDAS) and PCR methods for the detection of the pathogenic microorganisms Salmonella Typhimurium, Listeria monocytogenes, Escherichia coli O157:H7, Clostridium perfringens, and Staphylococcus aureus in salchich6n (a type of Spanish fermented dry sausage) was studied. The automated mini-VIDAS method and the PCR method were used to detect the presence of these microorganisms in 90 samples grouped into six batches (one control batch, and five batches inoculated with Salmonella Typhimurium, L. monocytogenes, E. coli O157:H7, S. aureus, and C. perfringens, respectively). The determinations were carried out on fresh sausage, semicured (14 days), and finished product (28 days of curing). The concordance between both methods was 100%. For salchichón-type sausage samples, both the VIDAS method and PCR (in comparison to traditional methods) permit a significant reduction in the time required for the detection of the pathogens assayed. The absence of Salmonella Typhimurium, E. coli O157:H7, L. monocytogenes, S. aureus, their enterotoxins, and C. perfringens were verified in the control batch. Conversely, for batches inoculated with these pathogens, the results were positive in the fresh sausage up to 14 days of curing and in the finished product; this demonstrated the null or scant influence of the curing conditions and the constitutive lactic acid biota on the pathogens investigated.

Hygienic behavior in the stingless bees Melipona beecheii and Scaptotrigona pectoralis (Hymenoptera: Meliponini).

Hygienic behavior, a trait that may confer resistance to brood diseases in the honey bee Apis mellifera, was studied in two species of stingless bees in Mexico. Eight colonies each of Melipona beecheii and Scaptotrigona pectoralis were tested for hygienic behavior, the removal of dead or diseased brood, by freeze killing a comb of sealed cells containing pupae. Both species detected and removed dead brood. However, removal rates differed between species. In M. beecheii colonies, workers took 2-9 days to remove 100% of the dead brood (4.4 +/- 2.0 days, mean +/- SD), while S. pectoralis removed all dead brood in less than 3 days (2.3 +/- 0.6 days, mean +/- SD). We conclude that hygienic behavior is not unique to A. mellifera, and is not solely an adaptation for the reuse of brood cells as occurs in honey bees but not stingless bees. Although stingless bees do not reuse brood cells, space is limited. The removal of dead brood may be necessary to allow new cells to be constructed in the same place.

Rhombohedral R3c to orthorhombic Pnma phase transition induced by Y-doping in BiFeO3.

In this work we study, by means of ab initio calculations, the structural, electronic and magnetic properties of Y-doped BiFeO3 compounds. We determine that there is a morphotropic phase boundary at an yttrium concentration of [Formula: see text], where the structure changes from R3c to Pnma. This structural transition is driven by the chemical pressure induced by the dopant. By analyzing the evolution of the oxygen octahedral tilts we find an enhanced antiferrodistortive distortion when increasing the Y-doping, together with a reduction of the ferroelectric distorsion, that gives rise to a smaller value of the electric polarization. These cooperative effects should lead to a larger canting of the Fe magnetic moments and to a larger ferromagnetic response in the R3c phase, as it is observed in the experiments.

Behaviour of the constitutive biota of two types of Spanish dry-sausages ripened in a pilot-scale chamber.

The behaviour of the constitutive biota in eighty four samples belonging to two different types of Spanish dry-cured sausages during the ripening process in a pilot-scale chamber was investigated. Samples were analyzed in three stages during production: fresh product, first drying stage and finished product. Lactic acid bacteria (LAB) and Coagulase-negative cocci (CNC) were identified by the API system. In general, evolution of LAB and CNC during the ripening process of Spanish dry-cured sausages increased during the first days after which numbers of these organisms remained stable. Pediococcus pentosaceus and Staphylococcus xylosus, were the dominant species. Lactobacillus plantarum, Staphylococcus saprophyticus Staphylococcus simulans and Kocuria varians were also present. The results obtained show that the ripening process in a pilot-scale chamber under controlled conditions contributes to a more homogeneous behaviour of the constitutive biota, in comparison with commercial production standards.

Influence of a test preservative on sponge cakes under different storage conditions.

A study was performed on 240 samples, divided into four batches, of sponge cakes baked following their industrial recipe to which different concentrations of a test preservative, mainly lactic acid and propylene glycol, were added. Each batch was submitted to three different temperature and relative humidity conditions. The counts of mesophilic aerobic bacteria, enterobacteria, enterococci, staphylococci, clostridia, lactic acid bacteria, and yeasts were less than 1 log CFU/g in all the batches studied and throughout the 120 days of study. Depending on batches and conditions, the mold counts were between less than 1 and 6.40 log CFU/g. Aspergillus, Eurotium, Penicillium, and Wallemia were detected and were potentially toxigenic in two cases. The test preservative added at 18 g/kg produced the greatest preserving effect, prolonging the product's shelf life by more than 4 months and showing itself to be effective at the other concentrations, especially at 15 degrees C and at 80 and 51% relative humidity.

Introduction of cyclofem once-a-month injectable contraceptive in Mexico.

A large introductory study of Cyclofem, a once-a-month injectable contraceptive, was conducted in three Mexican provinces. A total of 3457 healthy women participated: 640 women from rural areas (community-based component) and 2817 women from urban and suburban areas (health center-based component). A total of 20,316 women-months of treatment experience were accumulated during a one year period. Cyclofem proved its use-effectiveness (pregnancy rate of 0.03%) and its safety under routine service conditions of family planning facilities in Mexico. The overall life table continuation rate at 1 year was 26.1%. Higher continuation rates were observed in the community-based component (36.6%) as compared to the health center component (23.7%). The most common reason for method discontinuation was change of address. Only 15% of the discontinuations were attributable to the injectable contraceptive method, with the overall 1 year discontinuation rate for bleeding problems (including amenorrhea) was < 11%. These observations underscore the importance of appropriate counseling and follow-up measures, providing convenient access to repeat injections, and other service delivery issues related to continuation of Cyclofem. The results of this trial have once again demonstrated that Cyclofem is a highly effective method with an acceptable side effect profile. In addition, the study provided the elements for its approval by local health authorities and its inclusion into the Ministry of Health Family Planning Program.

PIP: The effectiveness and continuation rates associated with the once-a-month injectable contraceptive Cyclofem were investigated in an introductory trial conducted in three Mexican provinces (Sinaloa, Guanajuato, and Veracruz). Cyclofem contains 25 mg of medroxyprogesterone acetate and 5 mg of estradiol cypionate. A total of 3457 women (640 women from rural communities and 2817 from urban and suburban family planning centers) were enrolled and 20,316 woman-months of treatment experience were accumulated during the 12-month study period. The mean age of study participants was 23.6 years; 70% had previously used at least one contraceptive method. There was only one pregnancy (rate, 0.03%). The overall life-table continuation rate at 1 year was 26.1%, but this rate was higher in the community-based group (36.9%) than in the health center group (22.4%). This discrepancy is presumed to reflect the greater access of clinic clients to other contraception options. Continuation was highest among women 30-34 years of age, those with low levels of education, women with five or more children, and those who did not want more children. Only 14% of discontinuations were method-related. The 1-year discontinuation rate for bleeding problems, including amenorrhea, was 10.2%. These findings indicate Cyclofem is a safe, effective method appropriate for inclusion in Mexico's Ministry of Health Family Planning Program.

Evaluation of petrifilm series 2000 as a possible rapid method to count coliforms in foods.

This research note is a preliminary comparison between the Petrifilm 2000 method and a widely used traditional enumeration method (on violet red bile agar); six batches of different foods (egg, frozen green beans, fresh sausage, a bakery product, raw minced meat, and raw milk) were studied. The reliability of the presumptive counts taken at 10, 12, and 14 h of incubation using this method was also verified by comparing the counts with the total confirmed counts at 24 h. In all the batches studied, results obtained with Petrifilm 2000 presented a close correlation to those obtained using violet red bile agar (r = 0.860) and greater sensitivity (93.33% of the samples displayed higher counts on Petrifilm 2000), showing that this method is a reliable and efficient alternative. The count taken at 10-h incubation is of clear interest as an early indicator of results in microbiological food control, since it accounted for 90% of the final count in all the batches analyzed. Counts taken at 12 and 14 h bore a greater similarity to those taken at 24 h. The Petrifilm 2000 method provides results in less than 12 h of incubation, making it a possible rapid method that adapts perfectly to hazard analysis critical control point system by enabling the microbiological quality control of the processing.

Occurrence and behavior of Enterobacteriaceae and enterococci in mediterranean dry sausages during ripening in a Pilot-Scale chamber.

The occurrence and evolution of Enterobacteriaceae, coliforms, Escherichia coli, and enterococci in 252 samples of six types of Mediterranean dry-ripened sausages during maturation was investigated. The changes of the pH values were also recorded. Samples were analyzed in three steps of the ripening process: fresh product, first drying stage, and finished product. In all six sausages, Enterobacteriaceae, coliforms, and E. coli counts were characterized by high initial concentrations that significantly decreased during ripening. However, the initial counts of enterococci remained stable throughout the experiments in all sausages types. The average pH values of finished sausages ranged from 4.54 to 5.31.

Population dynamics of the constitutive biota of French dry sausages in a pilot-scale ripening chamber.

The population dynamic of constitutive biota on 84 samples belonging to two different types of French fermented dry sausages during the ripening process in a pilot-scale ripening chamber was investigated. Samples were analyzed in three steps of their production: fresh product, first drying stage, and finished product. In addition, 180 strains of lactic acid bacteria were identified using a miniaturized biochemical procedure of characterization. In general, the number of lactic acid bacteria that evolved during the ripening process of French dry sausages increased during the first days of the process after which the number of these organisms remained constant at approximately 8 log CFU/g. Lactobacillus sakei and Pediococcus pentosaceus, bacteria added as starter, were the dominant species. Pediococcus urinaeequi, Pediococcus acidilactici, and particularly Lactobacillus curvatus were also present. Finally, we have to take into account that the controlled conditions of the pilot plant generally contribute to the homogenization of the behavior of the starter biota.

Microbiological quality of terrestrial gastropods prepared for human consumption.

Hygienic quality was investigated in 60 samples of ready-to-eat snails (Helix lactea, Helix nemoralis, and Helix hortensis) obtained from 30 in-season street stalls and 30 catering establishments (bars) in Córdoba. In accordance with Spanish legislation regarding hygiene in the preparation, distribution, and sale of prepared foods, counts were obtained for total mesophilic aerobic bacteria, coliforms, total Enterobacteriaceae, Escherichia coli, Salmonella, and Staphylococcus aureus. The results obtained showed that 33.3, 20.0, and 13.3% of the samples from stalls and 73.3, 53.3, and 6.7% of the samples from bars did not comply with the regulations with respect to the control of total mesophilic aerobic bacteria, Enterobacteriaceae, and Staphylococcus aureus, respectively. Coliforms were found in 53.3% of the samples from the bars (mean, 2.1 CFU/g) and in 33.3% of the stalls (mean, 1.1 CFU/g). Salmonella was not detected.

Use of Lactobacillus acidophilus and Lactobacillus casei for a potential probiotic legume-based fermented product using pigeon pea (Cajanus cajan).

The aim of the present study was to evaluate the use of pigeon pea (Cajanus cajan) as an appropriate substrate in the production of a legume-based fermented product with Lactobacillus acidophilus ATCC 314 or Lactobacillus casei ATCC 393 and then to ascertain the effects of the addition of ingredients such as powdered milk and banana or strawberry sauce. The products were analyzed for viable cell counts, pH, and sensory attributes during product manufacture and throughout the refrigerated storage period at 3, 7, 14, 21, and 28 days. Nine types of products were produced. At the end of the storage period, the viability of L. acidophilus was above 7 log CFU/g in the presence of milk and 20% sucrose fruit sauce. For products with L. casei, the lack of ingredients such as milk caused no significant loss in viability; however, a high concentration of sucrose in the fruit sauce was an important factor in maintaining a high L. casei population. L. casei had high viability and good sensory attributes. Both strains could be considered suitable for a pigeon pea-based fermented potential probiotic product and a low-cost protein source.

Bactometer system versus traditional methods for monitoring bacteria populations in salchichón during its ripening process.

The performance of the Bactometer system (an impedimetric microbial monitoring system) compared with traditional methods (microbial colony counts) for monitoring bacterial populations (lactic acid bacteria [LAB], Enterobacteriaceae, and coliforms) was studied in 90 samples of an experimental salchichón (a type of Spanish ripened dry sausage) during its ripening process. The population quantitations were carried out with fresh sausage, semiripened sausage (14 days of ripening), and finished product (28 days of ripening). The results showed a high correlation between the traditional microbial colony count (in CFU per gram) and the impedance detection time: -0.98, -0.97, and -0.94 for coliforms, Enterobacteriaceae, and LAB, respectively (P < 0.01). Considering the results obtained with regard to the enumeration of populations of Enterobacteriaceae, coliforms, and LAB in salchichón during its ripening process, the advantages of impedance with respect to plate counts for monitoring the microbial dynamics of ripening processes are notable, especially in its time-saving aspects: between 19 and 21 h in the case of Enterobacteriaceae, between 7 and 20 h for coliforms, and between 32 and 46 h for LAB.

Proteolytic activity of lactic acid bacteria strains and fungal biota for potential use as starter cultures in dry-cured ham.

During the processing of dry-cured meat products, sarcoplasmic and myofibrillar proteins undergo proteolysis, which has a marked effect on product flavor. Microbial proteolytic activity is due to the action of mostly lactic acid bacteria (LAB) and to a lesser extent micrococci. The proteolytic capacity of molds in various meat products is of interest to meat processors in the Mediterranean area. Eleven LAB and mold strains from different commercial origins were tested for proteolytic activity against pork myosin, with a view to possible use of these strains as starter cultures for Iberian dry-cured ham. Proteolytic activity was tested by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The LAB strains with the highest proteolytic activity were Lactobacillus plantarum (L115), Pediococcus pentosaceus (Saga P TM), and Lactobacillus acidophilus (FARGO 606 TM). The best fungal candidate was Penicillium nalgiovense LEM 50I followed by Penicillium digitatum, Debaryomyces hansenii, and Penicillium chrysogenum.

Influence of low concentrations of an acid preservative on sponge cakes under different storage conditions.

In a previous study, we demonstrated the efficiency of an acid test preservative at concentrations higher than 10 g/kg of product. The aim of the current study has been to assay, in a pilot plant, a preservative at lower and different doses than tested in the aforementioned study, in contrast with different storage temperature and relative humidity (RH) conditions and to check the possibilities of the growth of molds with a toxigenic capacity. The effect of the test preservative is not demonstrable at very low concentrations, as occurs in batch 2. In this case, the influence of the other storage parameters, temperature and RH, has a mixed effect, which makes it difficult to draw conclusions about the convenience of the preservative. In our opinion, the minimal concentration of the test preservative to reach readable results is 4 g/kg, but it is not enough to guarantee a longer shelf life. Regarding the mycotoxigenic study, the majority of molds obtained in the isolations from the cakes after their macroscopic identification corresponded to the genera Aspergillus and Penicillium. Only 5 turned out to be mycotoxigenic, with citrinin and viridicatumtoxin being detected.