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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.
Before weaning, breast milk is the physiological form of neonatal nutrition, providing pups with all nutrient requirements. Maternal low-protein diet (LPD) during pregnancy and lactation induces adverse changes in key maternal organs, which have negative effects on pup development. We studied the effects of maternal LPD on liver weight, mammary gland (MG) cell differentiation, milk composition and production and pup development throughout lactation. We fed rats with control (C) or LPD (R) during pregnancy and lactation. At 7 d early, 14 d mid and 21 d late lactation stages, maternal biochemical parameters, body, liver and MG weights were analysed. MG cell differentiation was analysed by haematoxylin and eosin staining; milk nutrient composition and production were studied; pup body, liver and brain weights, hippocampal arachidonic acid (AA) and DHA were quantified. Results showed lower body and liver weights, minor MG cell differentiation and lower serum insulin and TAG in R compared with C. R milk contained less protein and higher AA at early and mid stages compared with C. R pup milk and fat intake were lower at all stages. R protein intake at early and mid stages and DHA intake at mid and late stages were lower compared with C. In R pups, lower body, liver and brain weights were associated with decreased hippocampal AA and DHA. We conclude that maternal LPD impairs liver and MG function and induces significant changes in maternal milk composition, pup milk intake and organ development.
We studied the genetic diversity and the population structure of human isolates of Histoplasma capsulatum, the causative agent of histoplasmosis, using a randomly amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR) assay to identify associations with the geographic distribution of isolates from Mexico, Guatemala, Colombia and Argentina. The RAPD-PCR pattern analyses revealed the genetic diversity by estimating the percentage of polymorphic loci, effective number of alleles, Shannon's index and heterozygosity. Population structure was identified by the index of association (IA) test. Thirty-seven isolates were studied and clustered into three groups by the unweighted pair-group method with arithmetic mean (UPGMA). Group I contained five subgroups based on geographic origin. The consistency of the UPGMA dendrogram was estimated by the cophenetic correlation coefficient (CCCr = 0.94, P = 0.001). Isolates from Mexico and Colombia presented higher genetic diversity than isolates from Argentina. Isolates from Guatemala grouped together with the reference strains from the United States of America and Panama. The IA values suggest the presence of a clonal population structure in the Argentinian H. capsulatum isolates and also validate the presence of recombining populations in the Colombian and Mexican isolates. These data contribute to the knowledge on the molecular epidemiology of histoplasmosis in Latin America.
The objective of this study was to determine the serotype distribution and antibiotic resistance of invasive pneumococcal disease (IPD) strains in children from Lima, Peru, before and after the introduction of the 7-valent pneumococcal conjugate vaccine (PCV7), which was introduced in the national immunisation program on 2009. We conducted a prospective, multicentre, passive surveillance IPD study during 2006–2008 and 2009–2011, before and right after the introduction of PCV7 in Peru. The study was performed in 11 hospitals and five private laboratories in Lima, Peru, in patients <18 years old, with sterile site cultures yielding Streptococcus pneumoniae. In total 159 S. pneumoniae isolates were recovered. There was a decrease in the incidence of IPD in children <2 years old after the introduction of PCV7 (18.4/100 000 vs. 5.1/100 000, P = 0.004). Meningitis cases decreased significantly in the second period (P = 0.036) as well as the overall case fatality rate (P = 0.025), including a decreased case fatality rate of pneumonia (16.3% to 0%, P = 0.04). PCV7 serotypes showed a downward trend. Vaccine-preventable serotypes caused 78.9% of IPD cases, mainly 14, 6B, 5, 19F and 23F. A non-significant increase in erythromycin resistance was reported. Our findings suggest that the introduction of PCV7 led to a significant decrease of IPD in children under 2 years old and in the overall case fatality rate.
This work presents the synthesis of selenium-based nanoparticles via microwave-assisted heating and their subsequent characterization using UV-vis Spectroscopy (UV-Vis), high-resolution transmission electron microscopy (HRTEM), and energy-dispersive X-ray spectroscopy (EDX), techniques. Ongoing research includes the study of the nanoparticles capacity to generate reactive oxygen species (ROS).
This research evidences the impact of Materials Science and Engineering Clubs as an outreach effort to expand the education and training required for a competitive Nanotechnology workforce beyond traditional STEM areas. An engineering perception questionnaire was implemented as a pre-test/post-test to track student perceptions and goals throughout the academic year to identify trends amongst gender and school level groups. Findings (107 students) show a perceived increase in student knowledge and interest for different fields of study, based on pre/post-test responses, with differences amongst gender and school level groups (middle school and high school). Also, significant differences in students’ aspirations for higher education degree were found among school level and gender. Results show that over 20% of participants increased their aspirations to higher education degrees and their interests in pursuing STEM degrees at end of the academic year. Specific findings on engineering perceptions and perceived level of knowledge and interest in science, engineering, materials, and nanotechnology as a result of club participation and student’s educational aspirations, expectations and future study plans are discussed along with implications for future STEM education.
OBJECTIVES/SPECIFIC AIMS: The aims of this study are (1) to develop and characterize a novel nonhuman primate model of pneumococcal pneumonia that mimics human disease; and (2) determine whether Streptococcus pneumoniae can: (a) translocate to the heart, (b) cause adverse cardiac events, (c) induce cardiomyocyte death, and (d) lead to scar formation during severe pneumonia in baboons. METHODS/STUDY POPULATION: Six adult baboons (Papio cynocephalus) were surgically tethered to a monitoring system to continuously assess their heart rate, temperature, and electrocardiogram (ECG). A baseline transthoracic echocardiogram, 12-lead ECG, serum troponin-I levels, brain natriuretic peptide, and heart-type fatty acid binding protein (HFABP) levels were obtained before infection and at the end of the experiment to determine cardiovascular damage during pneumococcal pneumonia. Animals were challenged with 108 colony-forming units of S. pneumoniae in the right middle lobe using flexible bronchoscopy. Three baboons were rescued with ampicillin therapy (80 mg/kg/d) after the development of pneumonia. Cardiac damage was confirmed by examination of tissue sections using immunohistochemistry as well as electron and fluorescence microscopy. Western-blots and tissue staining were used to determine the presence of necroptosis (RIP3 and pMLKL) and apoptosis (Caspase-3) in the cardiac tissue. Cytokine and chemokine levels in the heart tissue were determined using Luminex technology. RESULTS/ANTICIPATED RESULTS: Four males (57%) and three (43%) females were challenged. The median age of all baboons was 11 (IQR, 10-19) years old, which corresponds to a middle-aged human. Infected baboons consistently developed severe pneumonia. All animals developed systemic inflammatory response syndrome with tachycardia, tachypnea, fever, and leukocytosis. Infection was characterized by initial leukocytosis followed by severe leukopenia on day 3 postinoculation. Non-specific ischemic alterations by ECG (ST segment and T-wave flattering) and in the premortem echocardiogram were observed. The median (IQR) levels of troponin I and HFABP at the end of the experiment were 3550 ng/mL (1717–5383) and 916.9 ng/mL (520.8–1323), respectively. Severe cardiomyopathy was observed using TEM and H&E stains in animals with severe pneumonia. Necroptosis was detected in cardiomyocytes of infected animals by the presence of pMLKL and RIP3 in cardiac tissues. Signs of cardiac remodeling indicated by disorganized collagen deposition was present in rescued animals but not in the other animals. DISCUSSION/SIGNIFICANCE OF IMPACT: We confirmed that baboons experience cardiac injury during severe pneumococcal pneumonia that is characterized by myocardial invasion, activation of necroptosis, and tissue remodeling in animals rescued by antimicrobial therapy. Cardiac damage by invading pneumococci may explain why adverse cardiac events that occur during and after pneumococcal pneumonia in adult human patients.
A working group was held during the 2017 National Adaptation Forum to build collaborative capacity on issues related to Tribal agriculture and natural resource management in a changing climate. We developed three synthetic themes from these discussions and dialogue to highlight on-going opportunities, but also demonstrate areas for continued engagement with Tribes related to effective agricultural and natural resource management. We hope this forum demonstrates the critical importance of partnerships, and motivates further coordination and collaboration among Tribes, universities and Federal agencies.
Exposure to prenatal hypoxia in rats leads to intrauterine growth restriction (IUGR), decreases fetal cardiomyocyte proliferation and increases the risk to develop cardiovascular diseases (CVD) later in life. The tumor necrosis factor-related weak inducer of apoptosis (TWEAK) induces cardiomyocyte proliferation through activation of the fibroblast growth factor-inducible molecule 14 (Fn-14) receptor. The TWEAK/Fn-14 pathway becomes quiescent shortly after birth, however, it becomes upregulated with CVD; suggesting that it could be a link between the increased susceptibility to CVD in pregnancies complicated by hypoxia/IUGR. We hypothesized that offspring exposed to prenatal hypoxia will exhibit reduced cardiomyocyte proliferation due to reduced Fn-14 expression and that the TWEAK/Fn-14 pathway will be expressed in those adult offspring. We exposed pregnant Sprague Dawley rats to control (21% oxygen) or hypoxic (11% oxygen) conditions from gestational days 15 to 21. Ventricular cardiomyocytes were isolated from male and female, control and hypoxic offspring at postnatal day 1. Proliferation was assessed in the presence or absence of r-TWEAK (72 h, 100 ng/ml). Prenatal hypoxia was not associated with differences in Fn-14 protein expression in either male or female offspring. Cardiomyocytes from prenatal hypoxic male, but not female, offspring had decreased proliferation compared with controls. Addition of r-TWEAK increased cardiomyocyte proliferation in all offspring. In adult offspring of all groups, the TWEAK/Fn-14 pathway was not detectable. Cardiomyocyte proliferation was reduced in only male offspring exposed to prenatal hypoxia but this was not due to changes in the Fn-14 pathway. Studies addressing other pathways associated with CVD and prenatal hypoxia are needed.
Ni–Pt polyhedral nanoparticles were synthesized through a thermochemical route by the hot-injection method using Oleylamine (Oam) and Oleic acid (Oac) solvents as simultaneous stabilizing and reducing agents. Several syntheses were performed to study the effect of the hot-injection temperature on nanoparticle size distribution. Results revealed that the injection of precursors in a mixture of Oam and Oac at 180 °C produced paramagnetic nanoparticles with an approximate size of 27 nm; these particles have uniformly defined polyhedral structures and show greater Pt accumulation on the edges and corners. Ni–Pt polyhedral nanoparticles with larger sizes and high polydispersity were obtained as the injection temperature was increased closer to the reduction temperature.
We present radiocarbon (14C) in tree rings from Mexico City and a reconstruction of fossil CO2 concentrations for the last five decades, as part of a research program to understand the 14C dynamics in this complex urban area. Background values were established by 14C concentrations in tree rings from a nearby clean area. Agreement between background and NH-zone 2 values indicate Taxodium mucronatum is a good biomonitor for annual atmospheric 14C variations. Values for the urban tree rings were significantly lower than background values, indicating a 14C depletion from fossil CO2 emissions. There is an increasing trend of fossil CO2 between 1960 and 1990, in agreement with the population growth and the increasing demand for fossil fuels in Mexico City. Between 1990 and 2000, there is an apparent decrease in fossil CO2 concentration, increasing again after 2000. The decrease in 2000, despite being of the same magnitude as the overall uncertainty, may reflect environmental policies that improved the energy efficiency and reduced CO2 emissions in the area. The increase in fossil CO2 concentration between 2000 and 2010 may be attributable to the significant growth of motor vehicle usage in Mexico City, which made transportation the main energy-demanding and -emitting sector.
TAOS II is a next-generation occultation survey with the goal of measuring the size distribution of the small end of the Kuiper Belt (objects with diameters 0.5–30 km). Such objects have magnitudes r > 30, and are thus undetectable by direct imaging. The project will operate three telescopes at San Pedro Mártir Observatory in Baja California, México. Each telescope will be equipped with a custom-built camera comprised of a focal-plane array of CMOS imagers. The cameras will be capable of reading out image data from 10,000 stars at a cadence of 20 Hz. The telescopes will monitor the same set of stars simultaneously to search for coincident occultation detections, thus minimising the false-positive rate. This talk described the project, and reported on the progress of the development of the survey infrastructure.
Using the liquid phase epitaxy technique (LPE) Ga0.86In0.14As0.13Sb0.87 layers lattice-matched to (100) Te-GaSb have been deposited, which were intentionally doped with Te and Zn in a wide range. The Raman spectra show that the layers become more defective as the dopant molar fraction is increased. Two main vibrational bands are observed in the Raman spectra centred at 230 and 245 cm-1 that depend strongly on the Te (Zn) molar concentration, which are assigned to the vibrational modes GaAs-like and to (GaSb+InAs)-like mixture. The low-temperature photoluminescence of n (p)-type GaInAsSb was obtained as a function of Te (Zn) concentration added to the melt solution. The photoluminescence was interpreted taking into account nonparabolicity of the conduction (valence) band. It is shown that the band-to-band radiative transition energy can be used to estimate the free carrier concentration in GaInAsSb, for a wide range of doping concentration.
This paper summarizes the first tool that is able to predict Ground Level Enhancements (GLE). It makes real-time predictions of the occurrence of GLE events from the analysis of soft X-ray and differential proton flux measured by the GOES satellite network. Before the development of this tool, space weather systems have been warning users about evolving GLE events by processing neutron measurements recorded on ground level. This tool, called HESPERIA UMASEP-500, can predict GLE events before the detection by any neutron monitor (NM) station. The prediction performance measured for the period from 1986 to 2016 is presented for two consecutive periods, because of their notable difference in performance. For the 2000-2016 period, this prediction tool obtained a probability of detection (POD) of 53.8% (7 of 13 GLE events), a false alarm ratio (FAR) of 30.0%, and average warning times (AWT) of 8 min and 15 min with respect to the first NM station’s alert and the GLE Alert Plus warning, respectively. This project has received funding from the European Union’s Horizon 2020 research and innovation programme under agreement No 637324.