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Hernia is defined as the protrusion of one or several internal organs through an opening in the cavity that contains them due to a tissue defect, abdominal wall surgery by means of synthetic meshes is the most common method used for hernia repair, however, postsurgical effects can range from some discomfort, to chronic pain and even the reappearance of the hernia due to a poor mechanical adaptability between the synthetic tissue and the host tissue. The knowledge of the mechanical properties of the materials involved in hernia repair is fundamental in the understanding and subsequent solution of this type of problems. In this work, experimental data were obtained by means of uniaxial tensile tests in two perpendicular directions of commercial meshes used in hernia repair. The tests were carried out on the UniVert® machine of the CellScale® brand. Anisotropic mechanical behavior is observed due to the structure of the mesh and the interaction between each of the yarns that make it up. The data found vary with respect to the direction of traction and also has non-linear hyperelastic behavior, so the adjustment of curves was made through a hyperelastic model in the COMSOL Multiphysics® software through the Levenberg-Marquardt Algorithm for the characterization of these materials.
The relationship between epilepsy and the presence of visceral larva migrans caused by Toxocara canis in Mexican children remains uncertain; however, this relationship needs to be elucidated because these parasite larvae can invade the human central nervous system. Accordingly, this study aimed to determine the frequency and specificity of anti-T. canis antibodies in the sera of children with epilepsy to determine the relationship between this parasite and epilepsy. The sera samples of 214 children were examined: 111 children diagnosed with epilepsy and 103 clinically healthy children without neurological disorders. In the sera of each group, the presence and specificity of anti-T. canis and anti-Ascaris lumbricoides antibodies, as well as the cross-reactivity between them, were assessed using enzyme-linked immunosorbent assay and Western blotting analysis. Among the children with epilepsy, 25.2% exhibited seropositivity to T. canis. Cross-reactivity against the A. lumbricoides antigen was present in 46.8% of the children with epilepsy, whereas 11.7% of the children with epilepsy and anti-T. canis antibodies did not exhibit cross-reactivity against this antigen. The Western blotting analysis of the sera from the children with epilepsy demonstrated the presence of T. canis proteins, with molecular weights of 24, 35, 55, 70, 120 and 210 kDa, and A lumbricoides proteins with molecular weights of 70, 80 and 110 kDa. Our results revealed the presence of anti-T. canis antibodies in the children with epilepsy; furthermore, cross-reactivity tests with A. lumbricoides showed the importance of the presence of anti-T. canis antibodies in revealing the relationship between this parasite and epilepsy in children.
Disasters, such as cyclones, create conditions that increase the risk of infectious disease outbreaks. Epidemic forecasts can be valuable for targeting highest risk populations before an outbreak. The two main barriers to routine use of real-time forecasts include scientific and operational challenges. First, accuracy may be limited by availability of data and the uncertainty associated with the inherently stochastic processes that determine when and where outbreaks happen and spread. Second, even if data are available, the appropriate channels of communication may prevent their use for decision making.
In April 2019, only six weeks after Cyclone Idai devastated Mozambique’s central region and sparked a cholera outbreak, Cyclone Kenneth severely damaged northern areas of the country. By June 10, a total of 267 cases of cholera were confirmed, sparking a vaccination campaign. Prior to Kenneth’s landfall, a team of academic researchers, humanitarian responders, and health agencies developed a simple model to forecast areas at highest risk of a cholera outbreak. The model created risk indices for each district using combinations of four metrics: (1) flooding data; (2) previous annual cholera incidence; (3) sensitivity of previous outbreaks to the El Niño-Southern Oscillation cycle; and (4) a diffusion (gravity) model to simulate movement of infected travelers. As information on cases became available, the risk model was continuously updated. A web-based tool was produced, which identified highest risk populations prior to the cyclone and the districts at-risk following the start of the outbreak.
The model prior to Kenneth’s arrival using the metrics of previous incidence, projected flood, and El Niño sensitivity accurately predicted areas at highest risk for cholera. Despite this success, not all data were available at the scale at which the vaccination campaign took place, limiting the model’s utility, and the extent to which the forecasts were used remains unclear. Here, the science behind these forecasts and the organizational structure of this collaborative effort are discussed. The barriers to the routine use of forecasts in crisis settings are highlighted, as well as the potential for flexible teams to rapidly produce actionable insights for decision making using simple modeling tools, both before and during an outbreak.
This study assessed the in vitro anthelmintic (AH) activity of methanol and acetone:water leaf extracts from Annona squamosa, A. muricata and A. reticulata against Haemonchus contortus eggs. The egg hatch test was used to determine the effective concentrations required to inhibit 50% of eggs hatching (EC50). The role of polyphenols on AH activity was measured through bioassays with and without polyvinylpolypyrrolidone (PVPP). Methanolic extracts mainly caused the death of eggs at the morula stage (ovicidal activity). Meanwhile, acetone:water extracts caused egg-hatching failure of developed larvae (larvae failing eclosion (LFE) activity). The lowest EC50 values against H. contortus eggs were observed for the methanolic extracts from A. reticulata and A. muricata (274.2 and 382.9 µg/ml, respectively). From the six extracts evaluated, the methanolic extracts of A. muricata, A. reticulata and A. squamosa showed the highest ovicidal activity, resulting in 98.9%, 92.8% and 95.1% egg mortality, respectively. When the methanolic extract of A. squamosa was incubated with PVPP, its AH activity increased. Similarly, when acetone:water extracts of A. muriata and A. reticulata were incubated with PVPP, their LFE activity increased. Alkaloids were only evident in methanolic extracts, irrespective of PVPP incubation. The presence of acetogenins was not observed. In conclusion, methanolic extracts obtained from leaves of A. muricata, A. reticulata and A. squamosa showed ovicidal activity affecting the morula of H. contortus eggs, with minor LFE activity. Meanwhile, acetone:water extracts showed mostly LFE activity, with a lower proportion of ovicidal activity.
Although executive and other cognitive deficits have been found in patients with borderline personality disorder (BPD), whether these have brain functional correlates has been little studied. This study aimed to examine patterns of task-related activation and de-activation during the performance of a working memory task in patients with the disorder.
Sixty-seven DSM-IV BPD patients and 67 healthy controls underwent fMRI during the performance of the n-back task. Linear models were used to obtain maps of within-group activations and areas of differential activation between the groups.
On corrected whole-brain analysis, there were no activation differences between the BPD patients and the healthy controls during the main 2-back v. baseline contrast, but reduced activation was seen in the precentral cortex bilaterally and the left inferior parietal cortex in the 2-back v. 1-back contrast. The patients showed failure of de-activation affecting the medial frontal cortex and the precuneus, plus in other areas. The changes did not appear to be attributable to previous history of depression, which was present in nearly half the sample.
In this study, there was some, though limited, evidence for lateral frontal hypoactivation in BPD during the performance of an executive task. BPD also appears to be associated with failure of de-activation in key regions of the default mode network.
To provide cross-national data for selected countries of the Americas on service utilization for psychiatric and substance use disorders, the distribution of these services among treatment sectors, treatment adequacy and factors associated with mental health treatment and adequacy of treatment.
Data come from data collected from 6710 adults with 12 month mental disorder surveys across seven surveys in six countries in North (USA), Central (Mexico) and South (Argentina, Brazil, Colombia, Peru) America who were interviewed 2001–2015 as part of the World Health Organization (WHO) World Mental Health (WMH) Surveys. DSM-IV diagnoses were made with the WHO Composite International Diagnostic Interview (CIDI). Interviews also assessed service utilization by the treatment sector, adequacy of treatment received and socio-demographic correlates of treatment.
Little over one in four of respondents with any 12 month DSM-IV/CIDI disorder received any treatment. Although the vast majority (87.1%) of this treatment was minimally adequate, only 35.3% of cases received treatment that met acceptable quality guidelines. Indicators of social-advantage (high education and income) were associated with higher rates of service use and adequacy, but a number of other correlates varied across survey sites.
These results shed light on an enormous public health problem involving under-treatment of common mental disorders, although the problem is most extreme among people with social disadvantage. Promoting services that are more accessible, especially for those with few resources, is urgently needed.
First-degree relatives of patients with psychotic disorder have higher levels of polygenic risk (PRS) for schizophrenia and higher levels of intermediate phenotypes.
We conducted, using two different samples for discovery (n = 336 controls and 649 siblings of patients with psychotic disorder) and replication (n = 1208 controls and 1106 siblings), an analysis of association between PRS on the one hand and psychopathological and cognitive intermediate phenotypes of schizophrenia on the other in a sample at average genetic risk (healthy controls) and a sample at higher than average risk (healthy siblings of patients). Two subthreshold psychosis phenotypes, as well as a standardised measure of cognitive ability, based on a short version of the WAIS-III short form, were used. In addition, a measure of jumping to conclusion bias (replication sample only) was tested for association with PRS.
In both discovery and replication sample, evidence for an association between PRS and subthreshold psychosis phenotypes was observed in the relatives of patients, whereas in the controls no association was observed. Jumping to conclusion bias was similarly only associated with PRS in the sibling group. Cognitive ability was weakly negatively and non-significantly associated with PRS in both the sibling and the control group.
The degree of endophenotypic expression of schizophrenia polygenic risk depends on having a sibling with psychotic disorder, suggestive of underlying gene–environment interaction. Cognitive biases may better index genetic risk of disorder than traditional measures of neurocognition, which instead may reflect the population distribution of cognitive ability impacting the prognosis of psychotic disorder.
Asian Americans constitute 5% of the U.S. population. Their willingness to participate in research is important to examine because it influences participation rates and the representativeness of study results.
A total of 17,339 community members participated from six diverse Clinical and Translational Award (CTSA) sites. Community members were asked about their willingness to volunteer for eight different types of health research, their expectation of monetary compensation for research participation, their trust in research and researchers, their preferred language to receive health information, and their socio-demographic background. We examined Asian Americans’ willingness to participate in various types of health research studies and compared their perceptions with other racial/ethnic groups (i.e., Asian n = 485; African-American n = 9516; Hispanic/Latino n = 1889; Caucasian n = 4760; and other minority n = 689).
Compared to all other racial/ethnic groups, Asian Americans were less willing to participate in all eight types of health research. However, Asian Americans reported a lower amount of fair compensation for research participation than African-Americans and Hispanics/Latinos but were as likely to trust researchers as all other racial/ethnic groups.
Asian Americans are less willing to participate in health research than other racial/ethnic groups, and this difference is not due to dissatisfaction with research compensation or lower trust in researchers. Lack of trust in research and language barriers should be addressed to improve representativeness and generalizability of all populations in research.
Earlier activities on health technology assessment (HTA) started in Spain around 1984, with the creation of a National Advisory Board on HTA, and the development of national and regional HTA organizations in the early 1990s. In 2012, the Spanish Health Ministry established the Spanish Network for Health Technology Assessment of the National Health System (RedETS); funded at national level and including all public HTA organizations at national and regional levels. RedETSis focused on the assessment of nondrug health technologies to inform the revision (approval and funding or disinvestment) of the Benefit Portfolio of the Spanish NHS. In parallel with European Network for Health Technology Assessment (EUnetHTA), RedETS has been setting-up and sharing common procedures and methodological guidelines to ensure effective cooperation and mutual recognition of the scientific and technical production in HTA. The output of RedETS is fifty to sixty annual reports, including the production of full HTA reports, Clinical Practice Guidelines, methodological guidance reports, relative effectiveness assessments, tools to support shared decision making between patients and healthcare professionals, and monitoring studies. The HTA assessments requested by the Regional Health Authorities are the biggest component of the annual RedETS working plan. These assessment needs are identified according to a yearly process and prioritized by a Commission composed of representatives from all Spanish regions with the aid of the PRITEC tool. The objectives of this study are to report and update the normative and organizational state of HTA in Spain; describing noteworthy advances witnessed over the past 10 years, as well as discussing existing challenges.
The predominantly carbonate nature of the mountains near the coast of Málaga and Marbella (Costa del Sol, southern Spain) and the presence of springs have favored the formation of travertine buildups during the Quaternary. The geomorphic characteristics of the slopes and the location of the springs have determined the development of three types of travertine growths: (1) spring travertines, located preferentially on the south mountainside, where the slope is steepest; (2) pool-dam-cascade travertines, which form along the north and east edges, far from the carbonate relief and with a gentler slope; and (3) river-valley travertines, formed in the courses of the springs of any sector. Field observations combined with new amino acid racemization (AAR) dating of Helicidae gastropods show that most of the travertine formations are polyphasic and that their development was interrupted by stages of erosion and incision. Five stages of travertine development are evident, most of which are related to warm, moist episodes corresponding to marine oxygen isotope stages (MIS) 7, 5, 3, and 1, although local travertine growth also occurred during MIS 6 and during the transition from MIS 3 to 2.
The aim of this study was to develop a feasible and effective strategy to involve patients in the Spanish Network of Agencies of Health Technology Assessment (RedETS).
The framework for patient involvement (PI) in the assessment activities and processes of RedETS were developed through a research project that included: (i) a systematic search of the international literature describing a strategy and/or a methodology linking health technology assessment (HTA) and PI; (ii) a qualitative study through interviews with RedETS members to analyze the perceptions of PI among HTA managers in the Spanish context; (iii) a Delphi consultation with three large platforms of patients, carers and consumer organizations in Spain about their perspectives of PI; (iv) a consensus process with the members of the RedETS Governing Council to define the final strategy.
Three main themes were identified in the literature and Web site review: (i) PI methods for the different HTA phases; (ii) Participant definition and selection; (iii) Resources needed. A three-step implementation strategy was proposed: (i) short-term actions: piloting and testing patient participation in HTA and building patients' capacity; (ii) medium-term actions: broadening the participation of patients, and building internal capacity; (iii) long-term actions: consolidating and mainstreaming patient involvement
Patient participation can be incorporated into almost all the HTA phases and products with greater or lesser degrees of difficulty. However, a progressive implementation strategy is suggested for a feasible PI process.
Obtention of titanium (Ti)- and titanium dioxide (TiO2)–based nanocomposites is of great interest for biological nanomaterial applications, including for dental implants. Their mechanical properties can be improved by use of hydroxyapatite (HA) and chitosan through their biological anchorage with osseointegration and antibacterial activity. Electrochemical methods were chosen to obtain these composites in a quick and controllable way. In this work, electrochemical synthesis in one (alternated potential) or two steps (alternated or constant potential) was successfully applied. The single step (SS) obtained TiO2 + HA sample had different optical properties, as shown using ultraviolet–visible spectrometry, and the HA phase formation was proved using Raman spectroscopy. Thereby, SS_TiO2 + HA increased the corrosion resistance of titanium in artificial saliva medium, as shown by linear polarization and electrochemical impedance spectroscopy results. When using chitosan, the samples showed two corrosion interfaces, indicating its dissolution in human medium. These results indicate that the samples are excellent materials for dental implants.
In this work we apply high-resolution X-ray diffractometry to the study of InGaAs/GaAs multiple quantum well structures on (001) and(lll)B GaAs substrates. The samples consisted of p-i-n diodes with a multiple quantum well embedded in the i-region and were simultaneously grown on (001) and (111)B substrates by molecular beam epitaxy. For the characterization we have used symmetric and asymmetric reflections at different azimuthal positions. The interpretation of the diffraction profiles has been possible thanks to our recently developed simulation model, which allows the calculation of any reflection regardless of the substrate orientation. X-ray results about composition and thickness are very similar in the samples simultaneously grown on both orientations as expected from our specific growth conditions. The information obtained from X-ray characterization is consistent with the results of photoluminescence and photocurrent measurements within the experimental uncertainty of the techniques. In (lll)B samples, X-ray diffractometry provides structural information which cannot be easily obtained from optical characterization techniques.
Three sizes of beads 1, 2 and 3 mm of chitosan and poly (vinyl alcohol) were generated and crosslinked with ethylene glycol diglycidyl ether. The modification was carried out using a glass reactor, in which the beads were exposed to the glow discharge plasma (GDP). The adsorption experiments were carried out in triplicate at 30 °C, 200 rpm, 72 h at different pH values in the range between 2 and 7. The concentrations of the dye in the supernatants were determined by UV-vis spectrophotometry. The 1 mm beads with and without modification, as well as those adsorbed and without adsorbing were characterized by FTIR and SEM. A higher and constant adsorption capacity was observed using modified beads (814, 857 and 1509 mg/g for the 3, 2 and 1 mm beads, respectively). For unmodified beads the adsorption capacity decreased when the initial pH value was increased. This makes the beads modified by GDP a robust material with respect to pH variation and a good candidate to be used in the removal of synthetic dyes.
The aim of the present research was to evaluate pectin-gelatine and pectin-collagen polymeric compounds as encapsulating and releasing matrices for whey active peptides with antioxidant properties. Active peptides were obtained by hydrolysis of whey proteins with thermolysin and proteinase enzymes from B. subtilis. The hydrolysates were fractioned and encapsulated in the pectin composite matrices to obtain particles loaded with active whey peptides. The composite particles were analysed by SEM and IR techniques. In addition, they were also tested under simulated gastric conditions to evaluate the encapsulation efficiency and delivering power of the composite materials. The results showed that both encapsulation particles were excellent supports, because they retained to-the peptides and maintained their antioxidant activity during the simulated gastric process (120 min). However, the pectin gelatine particles were digested faster than those of pectin-collagen. The peptides from-encapsulated in pectin-gelatine were released within this time, showing an increment in the-antioxidant activity. Peptides from gelatine protein were also released by the gastric enzymes, and thus also they contributed to the antioxidant activity; in addition to the whey peptides.
This research shows the development of alternative Cu-based materials for applications where enhanced thermal properties are desired. Cu/AlN composites were fabricated from mixtures of pure Cu and copper plated AlN-Cu composite powders. The ceramic phase was added in amounts of 10, 20 and 30 vol.% and the mixtures sintered by pulsed electric current sintering process (PECS). The results showed that the AlN particles are homogeneously distributed in the copper matrix and that the true contacts between hard particles are reduced because of the deposited copper on their surfaces, improving the connectivity of the matrix phase and bonding at the metal-ceramic interface. The relative density of the Cu/AlN composites was major than 97% in all cases. Thermal conductivity of the composites was high and decreased with the ceramic content from 359 to 194 W/mK, for 10 and 30% AlN, respectively. The coefficient of thermal expansion followed a lineal behavior with temperature and is also reduced with the ceramic content.
Despite intensive research during the last few decades, understanding of ecological and physiological factors related to haemosporidian infections in birds is still fragmentary. Since more model organisms are needed in order to understand these infections in the wild, we analysed avian haemosporidian infections in the rufous-collared sparrow (Zonotrichia capensis, Emberizidae) in a dry forest of the Ecuadorian Andes. Parasite diversity was screened using molecular and morphological approaches. By molecular diagnosis, we identified three linages that were phylogenetically placed in the context of molecular haemosporidian diversity and associated with a morphospecies. By microscopy, we identified five described morphospecies and one additional undescribed morphospecies. We found that avian haemosporidian prevalence on the study site was 76.3%. Additionally, we used a series of generalized linear models to explore the potential relationship of parasite prevalence and parasitaemia with a set of variables related to physiological and environmental conditions. Although our results revealed associations of haemosporidian infections with precipitation, age and sampling site, the models only explained a small fraction of the variation.