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.

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.

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.

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.

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.

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.

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.

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.

Differentiation of Clostridium perfringens and Clostridium botulinum from non-toxigenic clostridia, isolated from prepared and frozen foods by PCR-DAN based methods

During the elaboration process of prepared and frozen foods, Clostridium sp. have been reported. From those microorganisms, C. perfringens and C. botulinum may pose a high risk for the consumers. To avoid these pathogenic organisms an HACCP program should be implemented, but in addition sensitive and moderately time consuming microbiological methods for monitoring C. perfringens and C. boulinum should be established. In this work, an RFLP analysis of the 16S rDNA will be developed to differentiate C. perfringens from other Clostridium sp. In addition, a PCR protocol, will be assayed to detect C. botulinum. Both two methods will be compared with biochemical characterization by API system. The restriction analysis of the 16S rDNA with Taq I and Rsa I showed at least the same sensitivity to differentiate C. perfringens from clostridial isolates as biochemical identification. However, the former method takes only 8-10 h of analysis as compared with 24-48 h required for biochemical characterization. With the specific PCR protocol to detect C. botulinum a band of 1.1 kbp was obtained derived from the specific amplification of BoNT genes, taking 6-8 h for analysis. Both two molecular DNA based methods should be considered as verification techniques of pathogenic clostridia in the HACCP program.

Effect of modified atmosphere packaging on the shelf life of sliced wheat flour bread

The application of modified atmospheres packaging (MAP) of sliced bread with different aw, moisture content and pH values, with or without preservative added (calcium propionate) and at different storage temperatures, has been studied with the aim of establishing the effect of MAP on the shelf-life of the selected product. Four atmospheres were tested per batch: 100% N2, 20% CO2/80% N2, 50% CO2/50% N2 and a standard air control. In samples without added preservative in CO2:N2 (50:50), the increases in shelf life were 117% and 158% at 22-25 degrees C and 15-20 degrees C, respectively. In samples with added preservative in 100% N2, shelf life was increased by 116%. Samples with added preservative in 20% CO2:80% N2 increased shelf life by 150% and 131% at 22-25 degrees C and 15-20 degrees C, respectively. By increasing the CO2 concentration to 50%, the increases in shelf life of the samples with added preservative were 167% and 195% at 22-25 degrees C and 15-20 degrees C, respectively.

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.

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.

Aflatoxin-Producing Strains of Aspergillus flavus Isolated from Cheese

Contamination by fungi of the genus Aspergillus with special reference to the possible detection of aflatoxin-producing strains of Aspergillus flavus was studied in 52 samples of commercial cheeses made with different types of milk (8 of cow's milk, 12 of ewe's milk, 13 of goat's milk, and 19 of milk mixtures of various species: cow, ewe, and goat) produced in Southern Spain. The frequency of appearance of various species of Aspergillus , A. glaucus , A. niger , A. nidulans , A. sulphureus , A. Terreus , and A. flavus , in the different types of cheese was determined. In 4 (2 of goat's milk cheese and 2 of cheeses made with milk from various species) out of 52 samples (7.69%), aflatoxin-producing strains of A. flavus were detected.

Occurrence of Aflatoxin M1 in Cheeses from the South of Spain

Thirty-five samples of commercial cheeses, 9 fresh, 9 semicured or semiripened and 17 ripened made with different types of milk (cow, ewe, goat and mixtures of milk of various species) produced in the South of Spain were analyzed for the presence of aflatoxin M₁ (AFM₁) by high-performance liquid chromatography, In 16 of the 35 samples (45.71%) the presence of AFM₁ was detected in concentrations ranging between 20 and 200 ng/g of cheese, In the positive cases, the mean levels of AFM₁ were 105.33 ng/g in ripened cheeses, 73.80 ng/g in semiripened cheeses and 42.60 ng/g in fresh cheeses.

Population Dynamics of Constitutive Microbiota in BAT Type Fermented Milk Products

Seventy samples from two batches of commercially produced fermented milk were analyzed for constitutive microbiota. Five samples were tested on the day of collection and the others analyzed after 10, 17, 24, 28, 31 and 36 days of storage at 7°C. M₁₇ agar was used to enumerate Streptococcus salivarius subsp. thermophilus . MRS (de Man, Rogosa, Sharpe) agar was used to enumerate Lactobacillus acidophilus . For the enumeration of Bifidobacterium spp. MRS agar to which antibiotic substances were added was used. In the case of Batch A, streptococci, lactobacilli and bifidobacteria were initially present at levels of 231.2 × 10⁶, 0.677× 10⁶ and 1.558 × 10⁶, respectively. The initial pH of 4.48 decreased to 4.12 after 24 days. For Batch B, streptococci, lactobacilli and bifidobacteria were initially present at levels of 858 × 10⁶, 190.7 × 10⁶ and 1.644 × 10⁶, respectively. The initial pH of 4.23 decreased to 4.07 and 3.84 after 24 and 36 days, respectively. The fall in the counts throughout refrigerated storage time showed some irregularities which, in our opinion, indicate a lack of control over the ecological aspects which affect the interrelation between the microorganisms involved. The statistical significance of the differences between the different trials was established throughout the time.

Survival of Constitutive Microflora in Commercially Fermented Milk Containing Bifidobacteria During Refrigerated Storage

The survival of constitutive microflora was studied in one batch (n = 50) of fermented milk containing bifidobacteria produced in Spain during storage at 7°C. Levels of Streptococcus salivarius subsp. thermophilus , Lactobacillus delbrueckii subsp. bulgaricus , and Bifidobacterium spp. and the pH of the product were determined on the day of collection and after 10, 17, 24, 28, 31, 36, 42, 51, and 84 d of storage. Initial populations of streptococci, lactobacilli, and bifidobacteria were 2.6 × 10⁸, 5.1 × 10⁷, and 7.4 × 10⁶ CFU/g, respectively. The S. salivarius subsp. thermophilus population increased slightly after 10 d and then decreased during further refrigerated storage. Numbers of Bifidobacterium and L. delbrueckii subsp. bulgaricus decreased faster during storage. After 24 d (the reported shelf life of the product), levels of streptococci decreased only 10.7% as compared to decreases of 85.4 and 92.6% for lactobacilli and bifidobacteria, respectively. The pH values were between 4.57 and 3.81.

Microbiological quality of French yogurts commercialized in Spain

The microbiological quality has been evaluated in 6 batches of yogurt (plain, flavoured and fruit-added) produced commercially in France and purchased in Spain. The essential microflora: Streptococcus salivarius subsp. thermophilus and Lactobacillus delbrueckii subsp. bulgaricus, and contaminants (coliform bacteria, yeasts and molds) were checked. The pH was also measured. The totality of the samples tested fulfilled French and Spanish regulation with respect to the presence of viable yogurt organisms. Likewise, in 100% of the yogurts, counts of contaminants were under 10 cfu/g. The pH ranged between 3.92 and 4.19.

Contaminating Mycoflora in Fermented Milk

The isolation, enumeration, and identification of yeasts and molds were carried out in 20 samples of commercial fermented milk containing bifidobacteria produced in Spain. Thirty percent of the samples yielded yeast counts of 10²/g or higher and 40% gave mold counts of 10/g or higher. In the nine samples in which the presence of yeasts was detected, Torulopsis Candida was the only species identified. A total of five molds was isolated and identified as belonging to the genera Aspergillus , Penicillium , Mirothecium , Paecylomices , and Mycogene . In two samples (10%), Aspergillus flavus (group) was detected.