Improved Metal Cation Optosensing Membranes through the Incorporation of Sulphated Polysaccharides.

Optosensing chitosan-based membranes have been applied for the detection of heavy metals, especially in drinking water. The novelty of this study is based on the use of sulphated polysaccharides, in such optosensing membranes, aiming at an improved analytical performance. The sulphated polysaccharides, such as ulvan, fucoidan and chondroitin sulfate, were extracted from by-products and wastes of marine-related activities. The membranes were developed for the analysis of aluminum. The variation in the visible absorbance of the sensor membranes after the contact between the chromophore and the aluminum cation was studied. The membranes containing sulphated polysaccharides showed improved signals when compared to the chitosan-only membrane. As for the detection limits for the membranes containing ulvan, fucoidan and chondroitin sulfate, 0.17 mg L-1, 0.21 mg L-1 and 0.36 mg L-1 were obtained, respectively. The values were much lower than that obtained for the chitosan-only membrane, 0.52 mg L-1, which shows the improvement obtained from the sulphated polysaccharides. The results were obtained with the presence of CTAB in analysis solution, which forms a ternary complex with the aluminum cation and the chromophore. This resulted in an hyperchromic and batochromic shift in the absorption band. When in the presence of this surfactant, the membranes showed lower detection limits and higher selectivity.

Epidemiology, molecular characterisation and antimicrobial susceptibility of Neisseria gonorrhoeae isolates in Madrid, Spain, in 2016.

With the aim to elucidate gonococcal antimicrobial resistance (AMR)-risk factors, we undertook a retrospective analysis of the molecular epidemiology and AMR of 104 Neisseria gonorrhoeae isolates from clinical samples (urethra, rectum, pharynx and cervix) of 94 individuals attending a sexually transmitted infection clinic in Madrid (Spain) from July to October 2016, and explored potential links with socio-demographic, behavioural and clinical factors of patients. Antimicrobial susceptibility was determined by E-tests, and isolates were characterised by N. gonorrhoeae multi-antigen sequence typing. Penicillin resistance was recorded for 15.4% of isolates, and most were susceptible to tetracycline, cefixime and azithromycin; a high incidence of ciprofloxacin resistance (~40%) was found. Isolates were grouped into 51 different sequence types (STs) and 10 genogroups (G), with G2400, ST5441, ST2318, ST12547 and G2992 being the most prevalent. A significant association (P = 0.015) was evident between HIV-positive MSM individuals and having a ciprofloxacin-resistant strain. Likewise, a strong association (P = 0.047) was found between patient age of MSM and carriage of isolates expressing decreased susceptibility to azithromycin. A decrease in the incidence of AMR gonococcal strains and a change in the strain populations previously reported from other parts of Spain were observed. Of note, the prevalent multi-drug resistant genogroup G1407 was represented by only three strains in our study, while the pan-susceptible clones such as ST5441, and ST2318, associated with extragenital body sites were the most prevalent.

Valorization of recurrently discarded fish species in trawler fisheries in North-West Spain.

The progressive elimination of fish discards established by the European Union Council in 2013 has stimulated the valorization of flesh from discarded high-quality species with good protein functional properties but which frequently have excessive fish-bones, fat, strange flavours, soft texture, etc. The present study therefore focuses on valorization of the extracted muscle (minced muscle), from several fish species frequently discarded in north-western Spanish fisheries (Atlantic Ocean): Blue whiting (Micromesistius poutassou), Mackerel (Scomber scombrus), Red scorpionfish (Scorpaena scrofa), Pouting (Trisoreptus luscus) and Gurnard (Trigla spp.). Valorization of these discarded fish resources is a key objective for the survival of the fishery sector in this area. In this regard present study was planned to examine the behaviour of the mince during 6 months of frozen storage by means of physicochemical and sensory analyses, and to test consumer acceptance of three technologically different products (burgers, nuggets and structured fingers) prepared with fish mince from different species. Results indicated that protein aggregation started at the outset of frozen storage but progressed very slowly, with the exception of non-washed blue whiting and red scorpionfish minces. Moreover, during frozen storage lipid oxidation increased in all samples; the increase was with two objectives highest in minced mackerel, a fatty fish, but no rancid flavour was detected. All mince samples presented acceptable physicochemical properties and good sensory acceptability after 6 months of frozen storage. Acceptability of final products made with these minces was high in all cases. Burgers were more acceptable for consumers aged over 40 and fingers and nuggets more for younger people.

Global Meningococcal Initiative: guidelines for diagnosis and confirmation of invasive meningococcal disease.

The Global Meningococcal Initiative (GMI) is an international group of scientists and clinicians with recognized expertise in meningococcal disease including microbiology, immunology, epidemiology, public health and vaccinology. The GMI was established to promote the global prevention of meningococcal disease through education, research and international cooperation. The GMI held its second summit meeting in 2013 to discuss the different aspects of existing meningococcal immunization programmes and surveillance systems. Laboratory confirmation and characterization were identified as essential for informing evidence-based vaccine implementation decisions. The relative merits of different confirmatory methodologies and their applications in different resource settings were a key component of the discussions. This paper summarizes the salient issues discussed, with special emphasis on the recommendations made and any deficiencies that were identified.

A new and general model to describe, characterize, quantify and classify the interactive effects of temperature and pH on the activity of enzymes.

We suggest a new and general model to describe the effects of temperature (T) and pH on the catalytic activity of enzymes. Despite the abundance of models to describe those effects, the current proposals are unsatisfactory, except for specific experimental cases in which the interactive mechanism between the two variables does not exist. For both variables, our solution analyses the activated and deactivated phases of an enzyme as phenomena of different nature. The system is described with independent probability functions. The interactive effects between T and pH are introduced with simple auxiliary functions. These functions describe the variations induced by each variable in the parameters that define the effects of the other. The structure of the resulting equation is, in theory and practice, very regular, which facilitates its use, and it is highly descriptive in different scenarios with or without interactive effects. The model was tested on three different enzymatic systems which are specifically designed to produce data for the evaluation of the effect of T and pH on the enzyme activity (A). Afterwards, our model was validated using results from other authors. Briefly, the authors found that: (1) other available models that were compared with our proposal were inefficient and in all cases our model provided the only statistically consistent solution; (2) in four cases, the enzymatic activity could only be explained if interactive effects are accepted; (3) synergy and antagonism concepts for the interaction between T and pH were described and classified; and (4) our solution is universal and independent of the structure of an enzyme and the reaction concerned.

Serogroup W meningococcal disease: global spread and current affect on the Southern Cone in Latin America.

Meningococcal serogroup W strains have been emerging throughout the current century with most of the isolates belonging to the sequence type (ST11)/electrophoretic type (ET37) clonal complex (ST11/E37 CC), particularly since the international outbreak following Hajj 2000. That outbreak appears to have triggered off that trend, contributing to the spread of W ST11/ET37 CC strains globally; however, local strains could be also responsible for increases in the percentage and/or incidence rates of this serogroup in some countries. More recently, unexpected increases in the percentage and incidence rate of W has been noticed in different countries located in the South Cone in Latin America, and W ST11/ET37 CC strains now appear as endemic in the region and an extensive immunization programme with tetravalent conjugate vaccine (covering serogroups A, C, Y and W) has been recently implemented in Chile. It is difficult to ascertain whether we are observing the emergence of W ST11 CC strains in different geographical areas or whether the Hajj 2000 strain is still spreading globally. Several aspects of the evolution of that situation are analysed in this paper, reviewing also the implications in immunization programmes. Closely related with the analysis of this potential evolution, it will be very interesting to monitor the evolution of serogroup W in the African meningitis belt after implementation of the extensive immunization programme with serogroup A conjugate vaccine that is currently underway. More data about carriers, transmission, clonal lineages, etc. are needed for taking decisions (target groups, outbreak control, defining the extent, etc.) to adapt the response strategy with potential interventions with broad coverage vaccines against the emergent serogroup W.

Self-expandable metal stents as a new treatment option for perforated duodenal ulcer.

Primary stenting and drainage has been shown to be an effective and safe way to treat esophageal perforations and anastomotic leaks after gastric bypass surgery. We present a case series of eight patients with perforated duodenal ulcers treated with covered self-expandable metal stents (SEMS). The first two patients received their stents because of postoperative leakage after initial traditional surgical closure. The following six patients had SEMS placed as primary treatment due to co-morbidities or technical surgical difficulties. Endoscopy and stent treatment in these six patients was performed at a median of 3 days (range, 0 - 7 days) after initial symptoms. Six patients had percutaneous abdominal drainage. Early oral intake, 0 - 7 days after stent placement, was possible. All patients except one recovered without complications and were discharged 9 - 36 days after stent placement. This series indicates that primary treatment with SEMS and drainage might be an alternative to surgery in patients with perforated ulcer disease.

Mediterranean diet adherence in individuals with prediabetes and unknown diabetes: the Di@bet.es Study.

BACKGROUND AND AIMS: Mediterranean diet (MedDiet) is causally related to diabetes and is a dietary pattern recommended to individuals with diabetes. We investigated MedDiet adherence in individuals with prediabetes and unknown (PREDM/UKDM) or known diabetes (KDM) compared to those with normal glucose metabolism (NORMAL). METHODS: This was a national, population-based, cross-sectional, cluster-sampling study. MedDiet adherence was scored (MedScore, mean ± SD 24 ± 5) using a qualitative food frequency questionnaire. Logistic regression was used to examine the association between MedScore and PREDM/UKDM or KDM versus control subjects. RESULTS: We evaluated 5,076 individuals. Mean age was 50 years, 57% were female, 826 (582/244) were PREDM/UKDM, 478 were KDM and 3,772 were NORMAL. Mean age increased across MedScore tertiles (46, 51 and 56 years, p < 0.0001). Higher age-adjusted adherence to MedDiet (5-unit increment in the MedScore) was associated with lower and nondifferent odds (OR, 95% CI) of prevalent PREDM/UKDM (0.88, 0.81-0.96, p = 0.001) and KDM (0.97, 0.87-1.07, p = 0.279), respectively, compared to individuals in the NORMAL group. CONCLUSIONS: In a representative sample of the whole Spanish population, MedDiet adherence is independently associated with PREDM/UKDM. Therapeutic intervention may be, in part, responsible for the lack of differences in adherence observed between the KDM and NORMAL groups. However, reverse causation bias cannot be ruled out in cross-sectional studies.

Prevalence of diabetes mellitus and impaired glucose regulation in Spain: the Di@bet.es Study.

AIMS/HYPOTHESIS: The Di@bet.es Study is the first national study in Spain to examine the prevalence of diabetes and impaired glucose regulation. METHODS: A population-based, cross-sectional, cluster sampling study was carried out, with target population being the entire Spanish population. Five thousand and seventy-two participants in 100 clusters (health centres or the equivalent in each region) were randomly selected with a probability proportional to population size. Participation rate was 55.8%. Study variables were a clinical and demographic structured survey, lifestyle survey, physical examination (weight, height, BMI, waist and hip circumference, blood pressure) and OGTT (75 g). RESULTS: Almost 30% of the study population had some carbohydrate disturbance. The overall prevalence of diabetes mellitus adjusted for age and sex was 13.8% (95% CI 12.8, 14.7%), of which about half had unknown diabetes: 6.0% (95% CI 5.4, 6.7%). The age- and sex-adjusted prevalence rates of isolated impaired fasting glucose (IFG), isolated impaired glucose tolerance (IGT) and combined IFG-IGT were 3.4% (95% CI 2.9, 4.0%), 9.2% (95% CI 8.2, 10.2%) and 2.2% (95% CI 1.7, 2.7%), respectively. The prevalence of diabetes and impaired glucose regulation increased significantly with age (p < 0.0001), and was higher in men than in women (p < 0.001). CONCLUSIONS/INTERPRETATION: The Di@bet.es Study shows, for the first time, the prevalence rates of diabetes and impaired glucose regulation in a representative sample of the Spanish population.

Breed differences over time and heritability estimates for production and reproduction traits of dairy goats in the United States.

To aid in improvement of breeding programs for production and reproduction traits of US dairy goats, breed differences over time were documented and genetic parameters were estimated. Data were from herds with ≥2 breeds (Alpine, LaMancha, Nubian, Oberhasli, Saanen, or Toggenburg), but only purebred data were analyzed. Three kidding periods were examined: 1976 through 1984, 1985 through 1994, and 1995 through 2005. Univariate repeatability mixed models were used to estimate least squares means by kidding period-breed and genetic parameters for milk, fat, and protein yields, combined fat and protein yield, fat and protein percentages, protein:fat ratio, age at first kidding, and kidding interval. Trends across kidding periods were favorable for most yield traits for all breeds but generally unfavorable for reproduction traits. Saanens had the highest milk (1,063 to 1,125 kg) and protein yields (31 to 33 kg). Nubians had the highest fat yields (37 to 40 kg) and lowest milk yields (791 to 851 kg). Oberhaslis had the lowest fat (31 to 33 kg) and protein (23 to 27 kg) yields. Alpines had the largest increase in milk yield (7.4%); Oberhaslis had the largest increase in protein (17.4%) and combined fat and protein (13.2%) yields. Combined fat and protein yield was higher for Nubians, Saanens, and Alpines (65 to 72 kg) than for LaManchas, Toggenburgs, and Oberhaslis (53 to 67 kg). Nubians had the highest fat (4.7 to 4.8%) and protein (3.6 to 3.8%) percentages. Only Nubians increased in fat percentage (2.1%); protein percentage increased most for Toggenburgs (7.4%) and Alpines (7.1%). Protein:fat ratio was highest for Toggenburgs (0.84 to 0.89) and lowest for Nubians (0.76 to 0.81), but Nubians had the largest increase in protein:fat ratio (6.6%). Saanens were oldest at first kidding (509 to 589 d), and Toggenburgs and LaManchas generally were youngest (435 to 545 d); age at first kidding increased most for Alpines (21.8%) and LaManchas (21.6%). Kidding intervals generally were shorter for Oberhaslis, LaManchas, and Nubians (350 to 377 d) than for Toggenburgs, Alpines, and Saanens (373 to 387 d). Kidding interval increased most for Nubians (3.9%) and Saanens (3.8%) and decreased only for Oberhaslis (5.4%). Heritability estimates across breeds were 0.35 for milk and fat yields, 0.37 for protein yield and protein:fat ratio, 0.36 for combined fat and protein yield, 0.52 for fat percentage, 0.54 for protein percentage, 0.23 for age at first kidding, and 0.05 for kidding interval. Genetic selection within breed is feasible for production and reproduction traits of US dairy goats.

Comparison of growth performance, carcass components, and meat quality between Mos rooster (Galician indigenous breed) and Sasso T-44 line slaughtered at 10 months.

The aim of this research was to make a full study of the meat from Mos-breed roosters (Spanish indigenous chicken). To achieve this purpose, the type of breed (Mos vs. a hybrid line, Sasso T-44) and the effect of finishing treatment in the last month (corn vs. commercial fodder) on growth performance, carcass and meat quality (physicochemical and textural traits), fatty and amino acid profile, and sensorial description were studied. The finishing feeding effect did not modify the growth, but the differences between genotypes were statistically significant (P < 0.05), in where Sasso T-44 was the genotype that generated the best growths and associated parameters. With regard to carcass characteristics, no significant influences of finishing feeding treatment (P > 0.05) were found, and carcass weight clearly differed between genotypes due to the lower growth rate of Mos roosters. Drumstick, thigh, and wing percentages were greater in Mos breed than in Sasso T-44 birds, whereas breast (15.2%), that is the most highly valued piece of the chicken, was similar for both genotypes. Significant differences in pH, protein, and ash content between genotypes have been found, whereas finishing feeding treatment had an effect on myoglobin and redness index (P < 0.01), showing meat from roosters fed with corn had a higher luminosity. Despite the fact of the slaughtered age of birds, values of shear force were slightly higher than 2 kg (2.11 kg) for both genotypes, thus it can be classified as very tender meat. Mos breed showed a higher percentage of polyunsaturated fatty acids (25.90 vs. 22.74; P < 0.001) and a lower percentage of monounsaturated fatty acids (35.14 vs. 38.95; P < 0.001) than Sasso T-44 chicken muscles. Surprisingly, birds finishing with the corn diet (2 times higher in linolenic acid than fodder) did not increase their polyunsaturated fatty acid level in the breast, obtaining in the Mos breed a polyunsaturated to saturated fatty acid ratio of 0.69. The amino acid profile of the indigenous-breed breast was not similar to that of the commercial-strain breast; besides, finishing feeding treatment had more of an effect on amino acid profile, affecting the majority of amino acids, with the exception of phenylalanine and threonine.

Breed effect between Mos rooster (Galician indigenous breed) and Sasso T-44 line and finishing feed effect of commercial fodder or corn.

The aim of this research was to study the Mos rooster breed growth performance, carcass, and meat quality. The breed effect (Mos vs. Sasso T-44) and finishing feed in the last month (fodder vs. corn) on animal growth, carcass characteristics, meat quality, and fatty and amino acid profiles were studied using a randomized block design with initial weight as covariance. In total, 80 roosters (n = 30 of Sasso T-44 line and n = 50 of Mos breed) were used. They were separated by breed and allocated to 2 feeding treatment groups (concentrate and corn). Each feeding treatment group consisted of 15 and 25 roosters, for Sasso T-44 line and Mos breed, respectively. Finishing feeding did not affect growth parameters in the 2 genotypes of rooster tested (P > 0.05). Nonetheless, the comparison between both types of roosters led to significant differences in growth parameters (P < 0.05). Regarding carcass characteristics, no significant influences of finishing feeding treatment (P > 0.05) were found, and as expected, carcass weight clearly differed between genotypes due to the lower growth rate of Mos roosters. However, drumstick, thigh, and wing percentages were greater in the Mos breed than in the hybrid line. In color instrumental traits, roosters feeding with corn showed breast meat with significantly (P < 0.001) higher a* and b* values than those of cocks feeding with commercial fodder. Values of shear force were less than 2 kg for both genotypes, thus it can be classified as very tender meat. Finishing with corn significantly increased (P < 0.001) the polyunsaturated fatty acid content in the breast; the Mos breed had a polyunsaturated to saturated fatty acid ratio of 0.73. The amino acid profile of the indigenous breed was not similar to that of the commercial strain. Finishing feeding treatment had a greater influence than breed effect on amino acid profile.

[Reproductive biology of Anisotremus interruptus (Perciformes: Haemulidae) in the Mexican Central Pacific]. / Biología reproductiva de Anisotremus interruptus (perciformes: Haemulidae) en el Pacífico central mexicano.

Anisotremus interruptus is a widely distributed and commercially important species in the Eastern Pacific. A multi-year research on the reproduction of this species was carried out in coastal waters of Jalisco, Mexico. For this purpose, monthly samples were gathered with gillnets of different mesh sizes from 1998-2008. A total of 1090 individuals were collected with a total length range between 15.6-61.0cm. Significant differences from expected 1:1 ratio were found for sex ratios in the total sample and for each size class, but not when comparisons among months and years were done. Temporal variations of the gonadosomatic index and proportions of maturation stages suggest that the main reproductive period is from February to May, although some less intensive spawning events were observed in other months. Seven stages of oocytes development were identified. Oocytes in different stages of development were identified in ovaries classified as mature, suggesting an asynchronic type of gonad development. Mean maturation length (L50) was 31.0 for females and 29.7cm for males. The internal organization of testes is of lobular type.

Study of the immunologic response of marine-derived collagen and gelatin extracts for tissue engineering applications.

The host immunologic response to a specific material is a critical aspect when considering it for clinical implementation. Collagen and gelatin extracted from marine sources have been proposed as biomaterials for tissue engineering applications, but there is a lack of information in the literature about their immunogenicity. In this work, we evaluated the immune response to collagen and/or gelatin from blue shark and codfish, previously extracted and characterized. After endotoxin evaluation, bone marrow-derived macrophages were exposed to the materials and a panel of pro- and anti-inflammatory cytokines were evaluated both for protein quantification and gene expression. Then, the impact of those materials in the host was evaluated through peritoneal injection in C57BL/6 mice. The results suggested shark collagen as the less immunogenic material, inducing low expression of pro-inflammatory cytokines as well as inducible nitric oxide synthase (encoded by Nos2) and high expression of Arginase 1 (encoded by Arg1). Although shark gelatin appeared to be the material with higher pro-inflammatory expression, it also presents a high expression of IL-10 (anti-inflammatory cytokine) and Arginase (both markers for M2-like macrophages). When injected in the peritoneal cavity of mice, our materials demonstrated a transient recruitment of neutrophil, being almost non-existent after 24 hours of injection. Based on these findings, the studied collagenous materials can be considered interesting biomaterial candidates for regenerative medicine as they may induce an activation of the M2-like macrophage population, which is involved in suppressing the inflammatory processes promoting tissue remodeling. STATEMENT OF SIGNIFICANCE: Marine-origin biomaterials are emerging in the biomedical arena, namely the ones based in marine-derived collagen/gelatin proposed as cell templates for tissue regeneration. Nevertheless, although the major cause of implant rejection in clinical practice is the host's negative immune response, there is a lack of information in the literature about the immunological impact of these marine collagenous materials. This work aims to contribute with knowledge about the immunologic response to collagen/gelatin extracted from blue shark and codfish skins. The results demonstrated that despite some differences observed, all the materials can induce a macrophage phenotype related with anti-inflammation resolution and then act as immuno-modulators and anti-inflammatory inducible materials.

Assessment of the in vitro kinetic activity of caspofungin against Candida glabrata.

Echinocandins have become the drug of choice in infections caused by Candida glabrata. The objective of this study was to evaluate the in vitro activity of caspofungin alone and in combination against C. glabrata. In vitro assays demonstrated that caspofungin alone showed excellent fungicidal activity against C. glabrata, including fluconazole-resistant strains. The combination of caspofungin and azole antifungals showed potential synergy against C. glabrata. Overall, caspofungin demonstrated excellent in vitro activity, alone and in combination, against strains of C. glabrata.

Short communication: genetic and environmental relationships between milk yield and kidding interval in dairy goats.

First-parity 305-d milk yield and intervals between first and second kiddings from 1975 through 2005 were analyzed to estimate genetic and environmental parameters for United States Alpine, LaMancha, Nubian, Saanen, and Toggenburg dairy goats. The data set included 43,612 does with first-parity milk yield and 25,863 does with first kidding interval. Parameters were estimated by REML using bivariate mixed models within and across breeds. Fixed effects were month and herd-year of kidding within breed and month and breed-herd-year of kidding across breeds. Random effects were animal and residual. The heritability estimate for first-parity milk yield was 0.36+/-0.01 across breeds and ranged from 0.35 to 0.38 within breed; heritability for first kidding interval was 0.05+/-0.01 across breeds and ranged from 0.00 to 0.15 within breed. The estimate of the genetic correlation between first-parity milk yield and first kidding interval was positive (unfavorable) across breeds (0.35+/-0.09). Estimates of environmental correlations within and across breeds were positive (0.16-0.25). The presence of unfavorable genetic relationships between milk yield and kidding interval indicates a need to include reproductive performance as a selection criterion.

[Trophic interactions of the six most abundant fish species in the artisanal fishery in two bays, central Mexican Pacific]. / Interacciones tróficas de las seis especies de peces más abundantes en la pesquería artesanal en dos bahías del Pacífico Central Mexicano.

We surveyed the trophic components in six species of Bahía de Navidad and Bahía de Chamela: Microlepidotus brevipinnis, Caranx caballus, Haemulon flaviguttatum, Lutjanus guttatus, L. argentiventris and Mulloidichthys dentatus. Two main seasonal periods were considered: 1) North Equatorial Counter Current NECC period influence (T1) and 2) California Current CC period influence (T2). In Bahía de Navidad 78 prey taxa were identified in the stomachs. From July to December (T1), 64 prey taxa were found, and from January to June (T2), 45 prey items. In Bahía de Chamela 93 prey items were identified; 74 during T1 and 60 during T2. The highest prey number was found in the stomachs of M. dentatus during T1 in Bahía de Navidad and the lowest prey number (7) was recorded in H. flaviguttatum in Bahía de Navidad in the same period. Crustaceans were the most frequently recorded prey items, followed by fishes, mollusks, polychaetes, and echinoderms in both seasonal periods and sites. The six fish species studied are considered as specialist feeders due the low values of the niche breadth index. There was little similarity among the diets.

From the limits of the classical model of sensitometric curves to a realistic model based on the percolation theory for GafChromic EBT films.

PURPOSE: Modern radiotherapy uses complex treatments that necessitate more complex quality assurance procedures. As a continuous medium, GafChromic EBT films offer suitable features for such verification. However, its sensitometric curve is not fully understood in terms of classical theoretical models. In fact, measured optical densities and those predicted by the classical models differ significantly. This difference increases systematically with wider dose ranges. Thus, achieving the accuracy required for intensity-modulated radiotherapy (IMRT) by classical methods is not possible, plecluding their use. As a result, experimental parametrizations, such as polynomial fits, are replacing phenomenological expressions in modern investigations. This article focuses on identifying new theoretical ways to describe sensitometric curves and on evaluating the quality of fit for experimental data based on four proposed models. METHODS: A whole mathematical formalism starting with a geometrical version of the classical theory is used to develop new expressions for the sensitometric curves. General results from the percolation theory are also used. A flat-bed-scanner-based method was chosen for the film analysis. Different tests were performed, such as consistency of the numeric results for the proposed model and double examination using data from independent researchers. RESULTS: Results show that the percolation-theory-based model provides the best theoretical explanation for the sensitometric behavior of GafChromic films. The different sizes of active centers or monomer crystals of the film are the basis of this model, allowing acquisition of information about the internal structure of the films. Values for the mean size of the active centers were obtained in accordance with technical specifications. In this model, the dynamics of the interaction between the active centers of GafChromic film and radiation is also characterized by means of its interaction cross-section value. CONCLUSIONS: The percolation model fulfills the accuracy requirements for quality-control procedures when large ranges of doses are used and offers a physical explanation for the film response.

Comparison of real-time PCR methods for quantification of European hake (Merluccius merluccius) in processed food samples.

The quantification of species in commercial products is limited by analytical shortcomings, as most of them provide semiquantitative results. An exception is real-time PCR, which can provide quantitative results using hybridization probes. In the present work, this technique has been applied to the absolute, absolute-relative and relative quantification of the most valued hake species in European markets, Merluccius merluccius (European Hake). The best quantification results for this species in binary mixtures with non-target species (Merluccius capensis) and using a species-specific real-time PCR MMER_VIC system was achieved using a relative quantification approach (MLL as reference system). Absolute quantification using the MLL nuclear system has been demonstrated as appropriate for the quantification of the Merluccius genus in food model samples. This study reveals the impact of different reference systems (MLL and HAKE) in the absolute-relative and relative quantification approaches, showing that the nuclear MLL system performed better than the mitochondrial HAKE system.

[From a pathogen's genome to an effective vaccine: the four-component meningococcal serogroup B vaccine]. / Del genoma de un patógeno a una vacuna efectiva: la vacuna de cuatro componentes frente a los meningococos del serogrupo B.

Invasive meningococcal disease (IMD), caused by the bacterium Neisseria meningitidis, entails significant mortality and morbidity. Disease incidence is highest in infants <1 year and young children globally. In Europe, N. meningitidis serogroup B is responsible for over 50% of overall IMD cases, whereas the majority of IMD cases in Latin America is caused either by serogroup B or C. The development of an effective vaccine against serogroup B has challenged the researchers for over half a century. Serogroup B capsular polysaccharide was an inappropriate vaccine antigen, and the success of outer membrane vesicle (OMV) vaccines was restricted to homologous bacterial strains. Reverse vaccinology led to the development of a 4-component meningococcal vaccine including three novel antigens, and OMVs (4CMenB). Each vaccine component has a different target. 4CMenB has been authorised based on its immunogenicity and safety data because the low disease incidence precluded formal clinical efficacy studies. Human serum bactericidal antibody (hSBA) assay tests functional antibodies in the serum of vaccinated individuals (i.e. the vaccine immunogenicity), and is the accepted correlate of protection. Vaccine strain coverage has been assessed both through hSBA assays and a more conservative method named Meningococcal Antigen Typing System (MATS). Effectiveness data of 4CMenB have been collected in the field since 2013. The vaccine proved effective in outbreak control in North America, and recent data from the introduction of the vaccine in the United Kingdom infant national immunisation programme reveal a vaccine effectiveness of 82.9% for the first two doses, with an acceptable safety profile.