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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.
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.
The purpose of this work is to study the effect of SiO2- and Al2O3-NPs on the microstructure and mechanical properties of the weld bead (WB) created by a process of Submerged Arc Welding (SAW) between two AISI 1025 steel plates. Also it was necessary consider the chemical compositions of slags and burned fluxes, in order to determine the elements that are deposited and contribute in the final microstructure of WB. The welding materials to form each WB were a M12K electrode, a commercial fused flux (CFF) and AISI 1025 steel plates bevelled at 45°. In addition SiO2- or Al2O3-NPs an ethylic alcohol mixture were applied directly to the beveled surfaces, just before the SAW process, which was carried out according to the AWS A5.17 norm. Microstructural and phase changes at the Heat Affected Zone (HAZ) and Welding Zone (WZ) were analysed by metallographic Optical and Scanning Electron Microscopies. The mechanical properties of the WBs were determined through Tensile, Charpy impact and Vickers Hardness tests. By means of metallography of WBs, it was determined that the length of the AF needles increases in 113 and 183 % when adding SiO2- or Al2O3-NPs, respectively. Related to the mechanical properties of the WB, the tensile and yield strength decreases with both additions, SiO2- or Al2O3-NPs. The microhardness at WZ was found to decrease by adding such oxide-NPs. Moreover, the impact energy absorbed by the WBs increases approximately by 83 or 57% due to SiO2- or Al2O3-NPs addition, respectively.
The neurocognitive trajectory in bipolar disorder (BD) is variable, with controversial findings, and most evidence come from cross-sectional studies. We aimed to examine the course of neurocognitive functioning in a sample of euthymic BD patients in comparison with a control group during a 5-year follow-up.
Ninety-nine euthymic bipolar patients and 40 healthy controls were assessed using a comprehensive neurocognitive battery (six neurocognitive domains) at baseline (T1) and then at 5-year follow-up (T2) in a longitudinal study.
No evidence of a progression in neurocognitive dysfunction was found either in cognitive composite index or in any of the neurocognitive domains for the whole cohort. However, there was a negative correlation between number of manic episodes and hospitalisations due to manic episodes and change in neurocognitive composite index (NCI) during the follow-up. Moreover, patients with higher number of manic and hypomanic episodes have a greater decrease in NCI, working memory and visual memory. History of psychotic symptoms was not related to the trajectory of neurocognitive impairment.
Our results suggest that, although the progression of cognitive decline is not a general rule in BD, BD patients who have a greater number of manic or hypomanic episodes may constitute a subgroup characterised by the progression of neurocognitive impairment. Prevention of manic and hypomanic episodes could have a positive impact on the trajectory of cognitive function.
Adults of Hysteromorpha triloba (Rudolpi, 1819), Lutz, 1931 inhabit primarily the intestine of cormorants across the globe, whereas metacercariae have been found in the body cavity of freshwater fishes of the families Cyprinidae, Ictaluridae, Ariidae, Pimelodidae and Catostomidae. In this study, adults and metacercariae identified as H. triloba were collected from the Neotropical cormorant (Nannopterum brasilianus) and from the Mexican tetra fish (Astyanax mexicanus) from the Gulf of Mexico and Pacific Ocean slopes in the Neotropical region. Partial DNA sequences of the mitochondrial gene cytochrome c oxidase subunit I (cox 1) and the internal transcribed spacers (ITS1, 5.8S and ITS2) of nuclear ribosomal DNA were generated for both developmental stages, and were compared with available sequences of H. triloba from the Nearctic region. The genetic divergence between metacercariae and adults of H. triloba from the Neotropical and Nearctic region (Canada) associated with the double-crested cormorant (Nannopterum auritus), ranged from 0 to 5.5% for cox 1 and from 0 to 0.2% for ITS. Phylogenetic analyses inferred with both molecular markers using maximum likelihood and Bayesian inference placed the adults and metacercariae in a single clade, confirming that both stages are conspecific. Our data confirmed that H. triloba is a widely distributed species across the Americas, parasitizing both the Neotropical and Nearctic cormorants in Argentina, Brazil, Venezuela, Mexico, USA and Canada.
Aluminum alloys have increased their use due to the properties such as low density, resistance to corrosion under environmental conditions and mechanical properties. In this work, the alloying elements are immiscible promoting dendrites formation with different phases attributed to zinc and tin. The applied mechanical stresses promoted the modification of the dendrite sizes (interdendritic space) as well as pore sizes and shapes. The microhardness decreased in the ternary Al-Zn-Sn alloy with a subsequent increase caused by microstructural changes after cold work. By XPS, the metallic elements were detected with an aluminum oxide layer.
Members of the genus Uvulifer are distributed worldwide and infect aquatic snails and freshwater fishes as first and second intermediate hosts, respectively, and fish-eating birds (kingfishers) as definitive hosts. Metacercariae of Uvulifer spp. were collected from the fins and skin of 20 species of freshwater fishes in Mexico, Guatemala, Honduras, Nicaragua and Costa Rica, and the adults were recovered from the intestine of kingfishers in four localities of Mexico. The genetic divergence among 76 samples (64 metacercariae and 12 adults) was estimated by sequencing the 28S and 5.8S nuclear genes, as well as the internal transcribed spacers ITS1 and ITS2, and one mitochondrial gene (cox1). Maximum likelihood and Bayesian inference analyses inferred with each dataset showed a high genetic diversity within the genus Uvulifer across Middle America, revealing the existence of four genetic lineages that exhibit some level of host specificity to their second intermediate hosts. The metacercariae of lineage 1 were associated with characids and cyprinids in central and northern Mexico. Metacercariae of lineages 2 and 3 were associated with cichlids distributed widely across Middle America. The lack of adults of these lineages in kingfishers, in lineages 2 and 3, or the fact that just a few adult specimens were recovered, as in lineage 1, prevented a formal description of these species. The metacercariae of lineage 4 were found in poeciliids, across a distribution range comprising Mexico, Guatemala, Honduras and Nicaragua, and the adult was found in the green kingfisher in Mexico. The number of specimens sampled for lineage 4, for both gravid adults and metacercariae, allowed us to describe a new species, Uvulifer spinatus n. sp. We describe the new species herein and we discuss briefly the genetic diversity in Uvulifer spp. and the importance of using DNA sequences to properly characterize parasite diversity.
Leishmaniasis is one of the world's most neglected diseases, and it has a worldwide prevalence of 12 million. There are no effective human vaccines for its prevention, and treatment is hampered by outdated drugs. Therefore, research aiming at the development of new therapeutic tools to fight leishmaniasis remains a crucial goal today. With this purpose in mind, we present 20 arylaminoketone derivatives with a very interesting in vitro and in vivo efficacy against Trypanosoma cruzi that have now been studied against promastigote and amastigote forms of Leishmania infantum, Leishmania donovani and Leishmania braziliensis strains. Six out of the 20 Mannich base-type derivatives showed Selectivity Index between 39 and 2337 times higher in the amastigote form than the reference drug glucantime. These six derivatives affected the parasite infectivity rates; the result was lower parasite infectivity rates than glucantime tested at an IC25 dose. In addition, these derivatives were substantially more active against the three Leishmania species tested than glucantime. The mechanism of action of these compounds has been studied, showing a greater alteration in glucose catabolism and leading to greater levels of iron superoxide dismutase inhibition. These molecules could be potential candidates for leishmaniasis chemotherapy.
The protein kinase R (PKR, also called EIF2AK2) is an interferon-inducible double-stranded RNA protein kinase with multiple effects on cells that plays an active part in the cellular response to numerous types of stress. PKR has been extensively studied and documented for its relevance as an antiviral agent and a cell growth regulator. Recently, the role of PKR related to metabolism, inflammatory processes, cancer and neurodegenerative diseases has gained interest. In this review, we summarise and discuss the involvement of PKR in several cancer signalling pathways and the dual role that this kinase plays in cancer disease. We emphasise the importance of PKR as a molecular target for both conventional chemotherapeutics and emerging treatments based on novel drugs, and its potential as a biomarker and therapeutic target for several pathologies. Finally, we discuss the impact that the recent knowledge regarding PKR involvement in metabolism has in our understanding of the complex processes of cancer and metabolism pathologies, highlighting the translational research establishing the clinical and therapeutic potential of this pleiotropic kinase.
In Spain, the use of annual cover crops is a crop management practice for irrigated vineyards that allows controlling vineyard vigor and yield, which also leads to improve the crop quality. Recently, Cynodon dactylon (bermudagrass) has been reported to infest those cover crops and colonize the grapevine rows, resulting in significant yield and economic losses due to the competition for water and nutrients. From timely unmanned aerial vehicle (UAV) imagery, the objective of this research was to map C. dactylon patches in order to provide an optimized site-specific weed management. A quadrocopter UAV equipped with a point-and-shoot camera was used to collect a set of aerial red-green-blue (RGB) images over a commercial vineyard plot, coinciding with the dormant period of C. dactylon (February 2016). Object-based image analysis (OBIA) techniques were used to develop an innovative algorithm for early discrimination and mapping of C. dactylon, which had the ability to solve the limitation of spectral similarity of this weed with cover crops or bare soil. As a general result, the classified maps of the studied vineyard showed four main classes, i.e. vine, cover crop, C. dactylon and bare soil, with 85% overall accuracy. These weed maps allow developing new strategies for site-specific control of C. dactylon populations in the context of precision viticulture.
As is well known, the corrosion of embedded steel reinforced depends strongly of the concrete resistivity, which is related directly with the water contained into its porous network. Environment plays an important role on resistivity, due to have a direct correspondence with the relative humidity and temperature. In these terms, ingress or output of water is favored or hampered by the environmental parameters, as well as its fluctuations. This work presents a proposal of instrumented system to generate a map of electrical resistivity at concrete samples by using superficial and embedded electrodes. Mathematical analysis of equivalent circuit revealed the importance of the impedance of electrodes utilized, to simplify measures. Concrete samples were exposed to different relative humidity focused to try to obtain the relation between relative humidity and resistivity. An array of two electrodes distributed in a matrix was manufactured to apply a signal of direct current at first electrode and measure the resultant current at second electrode. The system applies a programmed sequence of switch to turn on and turn off to realize measurements over established zone and, in this form, allows identify zones with potentials gradients. Also, do easy the monitoring of concrete resistivity evolution in function of time and humidity conditions.
The Antarctic Roadmap Challenges (ARC) project identified critical requirements to deliver high priority Antarctic research in the 21st century. The ARC project addressed the challenges of enabling technologies, facilitating access, providing logistics and infrastructure, and capitalizing on international co-operation. Technological requirements include: i) innovative automated in situ observing systems, sensors and interoperable platforms (including power demands), ii) realistic and holistic numerical models, iii) enhanced remote sensing and sensors, iv) expanded sample collection and retrieval technologies, and v) greater cyber-infrastructure to process ‘big data’ collection, transmission and analyses while promoting data accessibility. These technologies must be widely available, performance and reliability must be improved and technologies used elsewhere must be applied to the Antarctic. Considerable Antarctic research is field-based, making access to vital geographical targets essential. Future research will require continent- and ocean-wide environmentally responsible access to coastal and interior Antarctica and the Southern Ocean. Year-round access is indispensable. The cost of future Antarctic science is great but there are opportunities for all to participate commensurate with national resources, expertise and interests. The scope of future Antarctic research will necessitate enhanced and inventive interdisciplinary and international collaborations. The full promise of Antarctic science will only be realized if nations act together.
Crystals of Co2CO3(OH)2 have been synthesized under ambient conditions, in contrast to hydrothermal methods reported previously. We have developed a simple but efficient methodology to obtain an initial amorphous phase that evolves to a crystalline cobalt hydroxide carbonate after one week of maturation. X-ray diffraction analysis indicates that this phase crystallizes in the space group P21/a (a = 12.886(6), b = 9.346(3), c = 3.156(1) Å, β = 110.358(6)°). The platelet morphology of Co2CO3(OH)2 agrees with its lamellar crystal structure. High-resolution transmission electron microscopy (HRTEM) reveals that each individual platelet is comprised of nanodomains disoriented with respect to their neighbours. The kinetics and the activation energy (Ea = 6.26 kJ mol–1) of the transformation process have been estimated using the rate constant method. The precipitation of solids leads to a decrease in the cobalt concentration in the solution (∼88%) reaching values of ∼150 ppm, which can be considered a successful reduction from the perspective of water quality. The calcination in air of the synthetized platelets produced exclusively Co3O4. The thermo-X-ray difraction results confirm that Co2CO3(OH)2 is transformed over a small range of temperatures (225–235°C) into pure Co3O4. HRTEM images show that the lamellar nanomorphology is preserved in the Co3O4 phase. Therefore, understanding the crystallization behaviour of Co2CO3(OH)2 can help to minimize environmental problems caused by cobalt pollution and may facilitate the management of methods to obtain phases with specific nanomorphologies used widely in material sciences.
Control of fire was a hallmark of developing human cognition and an essential technology for the colonisation of cooler latitudes. In Europe, the earliest evidence comes from recent work at the site of Cueva Negra del Estrecho del Río Quípar in south-eastern Spain. Charred and calcined bone and thermally altered chert were recovered from a deep, 0.8-million-year-old sedimentary deposit. A combination of analyses indicated that these had been heated to 400–600°C, compatible with burning. Inspection of the sediment and hydroxyapatite also suggests combustion and degradation of the bone. The results provide new insight into Early Palaeolithic use of fire and its significance for human evolution.
Illegal killing/taking of birds is a growing concern across the Mediterranean. However, there are few quantitative data on the species and countries involved. We assessed numbers of individual birds of each species killed/taken illegally in each Mediterranean country per year, using a diverse range of data sources and incorporating expert knowledge. We estimated that 11–36 million individuals per year may be killed/taken illegally in the region, many of them on migration. In each of Cyprus, Egypt, Italy, Lebanon and Syria, more than two million birds may be killed/taken on average each year. For species such as Blackcap Sylvia atricapilla, Common Quail Coturnix coturnix, Eurasian Chaffinch Fringilla coelebs, House Sparrow Passer domesticus and Song Thrush Turdus philomelos, more than one million individuals of each species are estimated to be killed/taken illegally on average every year. Several species of global conservation concern are also reported to be killed/taken illegally in substantial numbers: Eurasian Curlew Numenius arquata, Ferruginous Duck Aythya nyroca and Rock Partridge Alectoris graeca. Birds in the Mediterranean are illegally killed/taken primarily for food, sport and for use as cage-birds or decoys. At the 20 worst locations with the highest reported numbers, 7.9 million individuals may be illegally killed/taken per year, representing 34% of the mean estimated annual regional total number of birds illegally killed/taken for all species combined. Our study highlighted the paucity of data on illegal killing/taking of birds. Monitoring schemes which use systematic sampling protocols are needed to generate increasingly robust data on trends in illegal killing/taking over time and help stakeholders prioritise conservation actions to address this international conservation problem. Large numbers of birds are also hunted legally in the region, but specific totals are generally unavailable. Such data, in combination with improved estimates for illegal killing/taking, are needed for robustly assessing the sustainability of exploitation of birds.
Although extrarenal manifestations of haemolytic–uraemic syndrome are not frequent, myocardial dysfunction should be given special consideration because of the importance of proper early haemodynamic management and potential complications. We report the case of a 21-month-old child with haemolytic–uraemic syndrome who developed clinical signs of poor myocardial function with depressed myocardial function noted by bedside echocardiography and significant elevation of biomarkers. Early intervention and supportive treatment for the patient were crucial during the acute phase of cardiac failure, and repeated monitoring of biomarkers and ecocardiography were useful diagnostic tools that provided relevant information throughout the patient’s evolution.
Stratigraphy, geochemistry and radiocarbon dating of a succession of sediment in the Santiaguillo Basin (central-northern Mexico) help reconstruct the millennial-scale dynamics of hydrological variability that occurred in the southern part of western subtropical North America since the late last glacial. Runoff was generally above average during the late last glacial from ~ 27 to 18 ka. Following this interval, runoff decreased and deposition of authigenic carbonate and aeolian transported sediment increased until ~ 4 ka. Heinrich 1 and 2, and Younger Dryas were intervals of reduced runoff and increased aeolian activity. The wetter climate of central-northern Mexico and arid conditions in north–northwestern Mexico during the late last glacial were probably related to formation of tropical cyclones in the eastern North Pacific during the autumn with restricted rainfall swaths and an absent/weaker North American Monsoon. Enhanced North American Monsoon and tropical cyclones with expanded rainfall swaths brought more summer and autumn precipitation to a broader region extending from the central-northern Mexico to the continental interiors of southwestern US during the early Holocene.
This study was designed to find out whether a person’s relationship with his voices and the negative affect he suffers from are mediated by beliefs about the voices. Research done to date shows contradictory results (Sorrell, Hayward, & Meddings, 2010, Vaughan & Fowler, 2004). A cross-sectional study was done to study the associations among variables, and a multiple mediation model (Preacher & Hayes, 2008) in which the beliefs about voices were the mediating variables was tested. Sixty subjects who heard voices participated. The VAY (Hayward, Denney, Vaughan, & Fowler, 2008), BAVQ (Chadwick & Birchwood, 1995), BAI (Beck & Steer, 1993) and BDI-II (Beck, Steer & Brown, 1996) were given. We found a significant positive correlation between perception of voices as dominant and intrusive and maintaining a position of distance from them on one hand, and negative affect [anxiety (r = .57, p < .001; r = .40, p < .001; r = .34, p < .01 respectively) and depression (r = .58, p < .001; r = .37, p < .01; r = .38, p < .001 respectively)] on the other. We also found that beliefs of malevolence and omnipotence mediated between relating style and negative affect (anxiety and depression). The theoretical implications of the results and clinical implications of the mediating relationships found are discussed.
Organic films with a thickness of few nanometers are potentially useful components in many practical and commercial applications such as sensors, detectors, displays and electronic circuit components. In this context, the Langmuir-Blodgett (LB) method is one the most promising techniques for preparing these films.
In this work, we report the synthesis and characterization of three new amphiphilic organometallic compounds with ferrocene units, which consist of one ferrocenyl aminocarbene with the general formula FcC=Cr(CO)5NH(CH2)15CH3, and two ferrocenyl amides with the general formula FcC=MNH(CH2)15CH3 where M = S or Se. These new derivatives have been synthesized to study the influence of long alkyl side chain and the hydrophilic head on the film organization behavior at the air-water interface.
The Langmuir-Blodgett (LB) technique was focused for building ordered nanostructures in molecular assemblies of ferrocenyl derivatives, which are apt to form a stable and transferable monolayer film. The π-A isotherm, hysteresis, Brewster angle microscopy (BAM) and film stability were used to characterize the behavior of a monolayer film at the air-water interface. Z- type LB films were prepared from molecular monolayers which were transferred onto glass substrates. These films were characterized by atomic force microscopy (AFM), UV-Visible spectra and X-ray diffraction (DRX) techniques.
The aim of the present study was to analyse demographic and clinical characteristics, as well as psychiatric diagnoses to identify gender differences in patients with attempted suicide in a Mexican population.
Between September 2010 and September 2012, 140 suicide attempts were documented in the Department of Psychiatry at the General Hospital of Comalcalco (Hospital General de Comalcalco in Spanish) in Tabasco, Mexico. Diagnoses were established using the DSM-IV questionnaire in which Axis I and II were considered. The Suicide Intent Scale was also applied.
In our sample, 63.6% were females and 36.4% males. With regard to socio-demographic characteristics, the predominant marital status in males was single, and in females married (χ2=5.93, df=2, p=0.05). In occupation the male group was mainly unemployed and housewife in females (χ2=55.51, df=4, p<0.001). Male subjects were more likely to consume alcohol (χ2=20.40, df=1, p≤0.001), cannabis (χ2=16.62, df=1, p≤0.001) or tobacco. The prevalence of psychiatric diagnosis was significantly different because, the male group was mainly diagnosed with substance-related disorders, whereas female participants showed a prevalence of stress-related disorders (χ2=34.17, gl=4, p=0.0001).
Our results provide evidence that the characteristics of suicide attempt are different by gender in the Mexican population. Interventions are necessary for the development of prevention strategies that may lead to a reduction in suicidal behaviour. These preventive activities should consider the occupation for the female group and consumption of alcohol, cannabis or tobacco in the male group.