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We present the kinematic results for the supernova remnant (SNR) CTB 1, obtained with the PUMA equipment of the 2.1-m telescope at San Pedro Mártir National Astronomical Observatory, Baja California, Mexico. The observations were made on the H α line using a Fabry–Perot interferometer. The kinematics derived from the Fabry–Perot velocity cubes allowed us to estimate a kinematic distance for this SNR. We estimate that CTB1 is about 3.8 kpc from the sun, corresponding to a linear diameter of 19 pc, with an expansion velocity of |$286 \rm ~ km ~s^{-1}$|⁠. Additionally, we analyse the diffuse X-ray emission from CTB 1 using data from the XMM–Newton observatory. From the best fits to the spectrum of southwest and northeast regions, we obtained a hot plasma temperature |$\sim 0.1-0.3 ~\rm keV$| with an overabundance in O and Ne and a lower abundance in Fe, which could be caused by a SNR with a stellar progenitor between 10 to |$70 \, \rm {\rm M}_{\odot }$|⁠. The initial energy of the supernova explosion is estimated between (0.6–1.0) × 1050 erg for soft X-ray emission. The X-ray emission also presents a non-thermal component of low surface brightness in the hard X-ray band. Images in radio and X-ray emission allow us to classify CTB 1 as mixed-morphology supernova type. The evolution models show that the cloudy ISM model is the only one that reproduces the mixed morphology type observed in the SNR CTB 1. [ABSTRACT FROM AUTHOR]

Anthropogenic activities are increasing the atmospheric carbon dioxide (CO2); around a third of the CO2 emitted by these activities has been taken up by the ocean. Nevertheless, this marine ecosystem service of regulation remains largely invisible to society, and not enough is known about regional differences and trends in sea-air CO2 fluxes (FCO2), especially in the Southern Hemisphere. The objectives of this work were as follows: first to put values of FCO2 integrated over the exclusive economic zones (EEZ) of five Latin-American countries (Argentina, Brazil, Mexico, Peru, and Venezuela) into perspective regarding total country-level greenhouse gases (GHG) emissions. Second, to assess the variability of two main biological factors affecting FCO2 at marine ecological time series (METS) in these areas. FCO2 over the EEZs were estimated using the NEMO model, and GHG emissions were taken from reports to the UN Framework Convention on Climate Change. For each METS, the variability in phytoplankton biomass (indexed by chlorophyll-a concentration, Chla) and abundance of different cell sizes (phy-size) were analyzed at two time periods (2000–2015 and 2007–2015). Estimates of FCO2 at the analyzed EEZs showed high variability among each other and non-negligible values in the context of greenhouse gas emissions. The trends observed at the METS indicated, in some cases, an increase in Chla (e.g., EPEA-Argentina) and a decrease in others (e.g., IMARPE-Peru). Evidence of increasing populations of small size-phytoplankton was observed (e.g., EPEA-Argentina, Ensenada-Mexico), which would affect the carbon export to the deep ocean. These results highlight the relevance of ocean health and its ecosystem service of regulation when discussing carbon net emissions and budgets. [ABSTRACT FROM AUTHOR]

Rheumatoid arthritis (RA) is an autoimmune inflammatory disease with an increased prevalence in Mexico. Although its etiology is unknown, its development can be influenced by environmental factors such as smoking and viral infections. But among the factors influencing susceptibility, it is the genetic factors that predominate, mainly the HLA-DRB1 genes, and specifically the alleles that have the shared epitope (SE). A transversal study was performed, in which 31 patients (28 women and 3 men) with RA, treated at the autoimmunity clinic of the High Specialty Hospital Ciudad Salud in Tapachula, Chiapas, southern México, were enrolled. Clinical, biochemical, and demographic data were analyzed; ESR (erythrocyte sedimentation rate), CRP (C-reactive protein), RF (rheumatoid factor), and ACPA (anticitrullinated peptide antibody) were recorded. All patients had at least one positive RA biological marker. For HLA alleles frequencies comparison, we enrolled ethnically matched healthy controls in a ratio of 3:1 for 25 cases and 4:1 for 6 cases in order to guarantee the balance between groups regarding the mean of age and proportion of gender (males vs females). HLA-DRB1*04 was found to be significantly increased in patients compared with ethnically matched healthy controls (p 0.0007, OR: 2.8, 95% CI 1.5–5.1); contrarily, DRB1*08 showed a protective effect (p 0.005, OR 0.1). This paper confirmed the involvement of HLA genes on risk determination for RA in a population of Mexican Mestizos from Tapachula, Chiapas. Key Points • HLA-DRB1*04 confirms the increased risk of rheumatoid arthritis. • HLA-DRB1*08 showed a more definite protective effect in southern Mexicans mestizos, a population with more Amerindian ancestry. [ABSTRACT FROM AUTHOR]

Abstract. Wave-induced extreme water levels in the Puerto Morelos fringing reef lagoon are investigated by means of a phase-resolving non-hydrostatic wave model (SWASH). This model solves the nonlinear shallow water equations including non-hydrostatic pressure. The one-dimensional version of the model is implemented in order to investigate wave transformation in fringing reefs. Firstly, the numerical model is validated with (i) laboratory experiments conducted on a physical model (Demirbilek et al., 2007) and (ii) field observations (Coronado et al., 2007). Numerical results show good agreement with both experimental and field data. The comparison against the physical model results, for energetic wave conditions, indicates that high- and low-frequency wave transformation is well reproduced. Moreover, extreme water-level conditions measured during the passage of Hurricane Ivan in Puerto Morelos are also estimated by the numerical tool. Subsequently, the model is implemented at different along-reef locations in Puerto Morelos. Extreme water levels, wave-induced setup, and infragravity wave energy are estimated inside the reef lagoon for different storm wave conditions (Hs > 2m). The numerical results revealed a strong correlation between the offshore sea-swell wave energy and the setup. In contrast, infragravity waves are shown to be the result of a more complex pattern which heavily relies on the reef geometry. Indeed, the southern end of the reef lagoon provides evidence of resonance excitation, suggesting that the reef barrier may act as either a natural flood protection morphological feature, or as an inundation hazard enhancer depending on the incident wave conditions. [ABSTRACT FROM AUTHOR]

The chigger species Acomatacarus coahuilensis n. sp. (Acariformes: Trombidiformes: Leeuwenhoekiidae) inhabiting the neck scales of the wary spiny lizard Sceloporus cautus Smith, 1938 (Squamata: Iguania: Phrynosomatidae), from Chihuahuan Desert Province, Coahuila, Mexico, is described herein. The new mite species is assigned to the genus AcomatacarusEwing, 1942, based on a palptarsus with 6 branched setae plus the tarsala (ω). This new species can be separated from the other species in this genus mainly based on the combination of the following characters: presence of mastisetae (MTa) on tarsus III and tibiala (φ) on tibia III, subterminala (ζ1), parasubterminala (z), and pretarsala (ζ2) on tarsus I, 2 genualae (σ1-2) on genu I, onychotriches and claw-like empodium of legs I-III, and absence of mastisetae on tibia III. In addition to the new species, the gastrointestinal nematode Skrjabinoptera phrynosoma (Ortlepp, 1922) Schulz, 1927 (Physalopteridae), was also found, which represents a new host record in the wary spiny lizard. This study reports the third species of the genus Acomatacarus recorded from Mexico and the first record of chigger mites and helminth parasites associated with Sc. cautus., (© American Society of Parasitologists 2023.)

HLA is a polymorphic antigen presenter which has provided valuable information on the susceptibility of populations to viruses. Therefore, the study of HLA can reveal specific susceptibility or resistance alleles to severe COVID-19 in an ethnically dependent manner. This pilot study investigated HLA alleles associated with COVID-19 severity in Tapachula, Chiapas, Mexico. A total of 146 Mexican Mestizos were typed for HLA class I and II using PCR-SSP. The patients were classified according to the outcome (death or improvement) and the infection's severity (mild or severe). In addition, a group of exposed uninfected individuals was included. HLA-A*68 was found to be a protective allele against the severe infection and fatal outcome; pC = 0.03, OR = 0.4, 95% CI =0.20-0.86, and pC =0.009, OR = 0.3, 95% CI =0.13-0.71 respectively. HLA-DRB1*03 also appears to be a protective factor against fatal outcome pC = 0.009, OR = 0.1, 95%IC = 0.01-0.66; however, the low frequency of this allele in the studied population limits the statistical power. The severity and fatal outcome of COVID-19 patients in Tapachula, Chiapas depend more on the lack of resistance than susceptibility HLA alleles., (Copyright © 2022 Elsevier Inc. All rights reserved.)

The marine-facultative Aspergillus sp. MEXU 27854, isolated from the Caleta Bay in Acapulco, Guerrero, Mexico, has provided an interesting diversity of secondary metabolites, including a series of rare dioxomorpholines, peptides, and butyrolactones. Here, we report on the genomic data, which consists of 11 contigs (N50~3.95 Mb) with a ~30.75 Mb total length of assembly. Genome annotation resulted in the prediction of 10,822 putative genes. Functional annotation was accomplished by BLAST searching protein sequences with different public databases. Of the predicted genes, 75% were assigned gene ontology terms. From the 67 BGCs identified, ~60% belong to the NRPS and NRPS-like classes. Putative BGCs for the dioxomorpholines and other metabolites were predicted by extensive genome mining. In addition, metabolomic molecular networking analysis allowed the annotation of all isolated compounds and revealed the biosynthetic potential of this fungus. This work represents the first report of whole-genome sequencing and annotation from a marine-facultative fungal strain isolated from Mexico.

Introduction: Systemic lupus erythematosus (SLE) is the prototypic autoimmune disease that disrupts numerous immunity mechanisms with the potential to exert damage to any organ or tissue. Its etiology remains uncertain; however, genetic and environmental factors that differ between populations strongly influence its development. Among the physiopathogenic factors, the genetic ones predominate, notably the major histocompatibility complex (MHC) loci. A high degree of ethnical admixture makes Mexican Mestizos a thoroughly genetically heterogeneous population. Therefore, this study aimed to identify the MHC polymorphisms associated with SLE development in Mexican Mestizos from Southern Mexico and compare them with patients from Mexico City., Method: A transversal study in SLE patients from Tapachula, Chiapas, was conducted. DNA typing of human leukocyte antigens (HLA) classes I and II was performed using single specific primers (SSP). Admixture analysis was performed using the population genetics LEADMIX software., Results: The frequencies of HLA-DRB1*16 and HLA-DQB1*05 were found to have a tendency towards increase in SLE patients, compared to ethnically matched healthy controls. The allele HLA-DRB1*03 seemed to be less associated with SLE in this group of Mexican Mestizos, opposed to other more Caucasian populations. Admixture analysis showed a higher Mayan genetic component in these patients from Chiapas., Conclusions: The genetic susceptibility for SLE differed in two populations of Mexican Mestizos with dissimilar ethnic ancestries. Autochthonous Amerindian alleles, and not the more widely known Caucasian alleles, might be associated with the susceptibility to SLE in Mexican Mestizos from Tapachula, Chiapas. Key Points • Autochthonous Amerindian alleles, such as HLA-DRB1*16, had a tendency to be increased in SLE patients, compared to healthy controls. • SLE susceptibility alleles vary considerably among regions in Mexico, according to the distribution of the indigenous groups. • Ethnic admixture is a key determinant in the genetic susceptibility of SLE., (© 2021. International League of Associations for Rheumatology (ILAR).)

Background: On March 11, 2020, the World Health Organization declared the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) pandemic, and on February 28, Mexico reported its first case. Internationally, cases in newborns are few and the outcomes, in general, are good. There is no certainty of possible vertical transmission, and the presence of the virus in human milk is improbable. The gold standard for diagnosis is the reverse transcription-polymerase chain reaction (RT-PCR) test. We performed a literature review and presented a case of perinatal COVID-19., Clinical Case: We describe the case of a full-term male infant with a birth weight of 3450 g and history of rooming-in with another mother-baby pair, both positive for SARS-CoV-2. On the second day of life, the neonate developed pneumonia, with clinical, X-ray and ultrasound diagnostic confirmation. On the third day of life, RT-PCR was positive for SARS-CoV-2; the mother was also positive but remained asymptomatic. The patient required mechanical ventilation and was transferred to a tertiary level neonatal unit on day 5 of life, where congenital heart disease was ruled out. He evolved satisfactorily with a negative RT-PCR test for SARS-CoV-2 on day 8 and was extubated and discharged on day 21 of life. Telephone follow-up was performed without complications., Conclusions: The present case was classified as horizontal transmission with a short incubation period of COVID-19., (Copyright: © 2021 Permanyer.)

Biological invasion is one of the main threats to native biodiversity. For a species to become invasive, it must be voluntarily or involuntarily introduced by humans into a nonnative habitat. Mammals were among first taxa to be introduced worldwide for game, meat, and labor, yet the number of species introduced in the Neotropics remains unknown. In this data set, we make available occurrence and abundance data on mammal species that (1) transposed a geographical barrier and (2) were voluntarily or involuntarily introduced by humans into the Neotropics. Our data set is composed of 73,738 historical and current georeferenced records on alien mammal species of which around 96% correspond to occurrence data on 77 species belonging to eight orders and 26 families. Data cover 26 continental countries in the Neotropics, ranging from Mexico and its frontier regions (southern Florida and coastal-central Florida in the southeast United States) to Argentina, Paraguay, Chile, and Uruguay, and the 13 countries of Caribbean islands. Our data set also includes neotropical species (e.g., Callithrix sp., Myocastor coypus, Nasua nasua) considered alien in particular areas of Neotropics. The most numerous species in terms of records are from Bos sp. (n = 37,782), Sus scrofa (n = 6,730), and Canis familiaris (n = 10,084); 17 species were represented by only one record (e.g., Syncerus caffer, Cervus timorensis, Cervus unicolor, Canis latrans). Primates have the highest number of species in the data set (n = 20 species), partly because of uncertainties regarding taxonomic identification of the genera Callithrix, which includes the species Callithrix aurita, Callithrix flaviceps, Callithrix geoffroyi, Callithrix jacchus, Callithrix kuhlii, Callithrix penicillata, and their hybrids. This unique data set will be a valuable source of information on invasion risk assessments, biodiversity redistribution and conservation-related research. There are no copyright restrictions. Please cite this data paper when using the data in publications. We also request that researchers and teachers inform us on how they are using the data., (© 2020 The Authors. Ecology © 2020 The Ecological Society of America.)

Human papillomavirus (HPV) infections are associated with the development of anogenital lesions in men. There are no reports describing the distribution of non-α HPV types in the anal canal of a sexually diverse group of men. The HPV Infection in Men (HIM) Study is a multicentre study on the natural history of HPV infection in Brazil, Mexico, and the USA. At baseline, 12% of anal canal PCR HPV-positive specimens were not typed by the Roche Linear Array, and were considered to be unclassified. Our goals were to characterize HPVs among these unclassified specimens at baseline, and to assess associations with participant socio-demographic and behavioural characteristics. Unclassified HPVs were typed by sequencing of amplified PGMY09/11 products or cloning of PGMY/GP + nested amplicons followed by sequencing. Further analysis was conducted with FAP primers. Of men with unclassified HPV in the anal canal, most (89.1%) were men who have sex with women. Readable sequences were produced for 62.8% of unclassified specimens, of which 75.2% were characterized HPV types. Eighteen, 26 and three different α-HPV, β-HPV and γ-HPV types were detected, respectively. α-HPVs were more commonly detected among young men (18-30 years) than among older men (45-70 years), whereas β-HPVs were more frequent among mid-adult men (31-44 years). β-HPVs were more common among heterosexual men (85.0%) than among non-heterosexual men. All β-HPVs detected among non-heterosexual men were β2-HPV types. The high prevalence of β-HPV in the anal canal of men who do not report receptive anal sex is suggestive of other forms of transmission that do not involve penile-anal intercourse., (Copyright © 2015 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.)

Municipal water disinfection systems in some areas are not always able to meet water consumer needs, such as ensuring distributed water quality, because household water management can be a contributing factor in water re-contamination. This fact is related to the storage options that are common in places where water is scarce or is distributed over limited time periods. The aim of this study is to assess the removal capacity of a multiple-barrier water disinfection device for protozoa, bacteria, and viruses. Water samples were taken from households in Mexico City and spiked with a known amount of protozoa (Giardia cyst, Cryptosporidium oocyst), bacteria (Escherichia coli), and viruses (rotavirus, adenovirus, F-specific ribonucleic acid (FRNA) coliphage). Each inoculated sample was processed through a multiple-barrier device. The efficiency of the multiple-barrier device to remove E. coli was close to 100%, and more than 87% of Cryptosporidium oocysts and more than 98% of Giardia cysts were removed. Close to 100% of coliphages were removed, 99.6% of the adenovirus was removed, and the rotavirus was almost totally removed. An effect of site by zone was detected; this observation is important because the water characteristics could indicate the efficiency of the multiple-barrier disinfection device.

Identifying factors associated with condyloma are necessary for prevention efforts. Risk factors for incident condyloma were examined in a cohort of 2487 men from the United States, Brazil, and Mexico and were followed up every 6 months (median, 17.9 months). Factors strongly associated with condyloma were incident infection with human papillomavirus (HPV) types 6 and 11 (hazard ratio [HR], 12.42 [95% confidence interval {CI}, 3.78-40.77]), age (HR, 0.43 [95% CI, .26-.77]; 45-70 vs 18-30 years), high lifetime number of female partners (HR, 5.69 [95% CI, 1.80-17.97]; ≥21 vs 0 partners), and number of male partners (HR, 4.53 [95% CI, 1.68-12.20]; ≥3 vs 0 partners). The results suggest that HPV types 6 and 11 and recent sexual behavior are strongly associated with incident condyloma.

Male sexual behavior influences the rates of cervical dysplasia and invasive cervical cancer, as well as male human papillomavirus (HPV) infection and disease. Unfortunately, little is known regarding male HPV type distribution by age and across countries. In samples combined from the coronal sulcus, glans penis, shaft, and scrotum of 1,160 men from Brazil, Mexico, and the United States, overall HPV prevalence was 65.2%, with 12.0% oncogenic types only, 20.7% nononcogenic types only, 17.8% both oncogenic and nononcogenic, and 14.7% unclassified infections. Multiple HPV types were detected in 25.7% of study participants. HPV prevalence was higher in Brazil (72.3%) than in the United States (61.3%) and Mexico (61.9%). HPV16 (6.5%), HPV51 (5.3%), and HPV59 (5.3%) were the most commonly detected oncogenic infections, and HPV84 (7.7%), HPV62 (7.3%), and HPV6 (6.6%) were the most commonly detected nononcogenic infections. Overall HPV prevalence was not associated with age. However, significant associations with age were observed when specific categories of HPV, nononcogenic, and unclassified HPV infections were considered. Studies of HPV type distribution among a broad age range of men from multiple countries is needed to fill the information gap internationally with respect to our knowledge of HPV infection in men.

Objective: To identify risk factors associated to surgical site infection (SSI) in newborns., Design: Case-control study. Site. Neonatal intensive care unit (NICU), Hospital de Pediatría, Centro Medico Nacional SXXI, IMSS., Patients: 279 patients were included (125 cases and 154 controls)., Data: Gestational age, birth weight, previous infection, hospital stay, type of surgery, surgical drains, length of surgical procedure, bleeding during surgery, surgical site classification, serum albumin, classification of infection and surgeon performing the procedure., Results: Five independent factors associated to SSI were identified: surgical reinterventions (OR = 13.6, CI 95% = 4.3-42.7); length of surgery > 60 minutes (OR = 3.0, CI 95% = 1.4-6.3); preoperative stay > 5 days (OR = 2.8, CI 95% = 1.3-5.6); consultant surgeon (OR = 2.7, CI 95% = 1.3-5.3), and previous systemic infection (OR = 2.1, CI 95% = 1.1-4.3). Lethality was 8.2% (n = 23), 74% in the group of cases (n = 17)., Conclusions: Factors associated to SSI are mainly related to the characteristics of surgery and those of the patient. Lethality was low, but most of deaths were in the group of cases.

Objective: To determine whether supervision and self-assessment activities can improve doctor-patient communication., Setting and Participants: Six supervisors, 60 doctors in their last year of training, and 232 primary health care patients at rural health clinics in Michoacan, Mexico., Design: The main evaluation compared post-intervention measures in control and intervention groups. A small panel study also examined changes from baseline to post-intervention rounds in both groups., Intervention: Over a 4-month period, specially trained supervisors added 1 hour of supervision on interpersonal communication and counseling (IPC/C) to regular site visits. Doctors, who had received prior IPC/C training, periodically audiotaped and assessed their own consultations., Main Outcome Measures: These comprised frequency of doctors' facilitative communication, doctors' biomedical information-giving, and patients' active communication., Results: The performance of all doctors improved markedly over the study period, but gains in facilitative communication and information-giving were significantly greater in the intervention than the control group. No single component of the intervention was responsible for the improvement; it resulted from the combination of activities. The doctors appreciated the more supportive relationship with supervisors that resulted from the intervention and found listening to themselves on audiotape a powerful, although initially stressful, experience., Conclusion: Supportive supervision and self-assessment activities can reinforce IPC/C training, prompt reflection and learning, and help novice doctors improve their interpersonal communication skills.

Objective: To report survival of newborns with congenital heart disease who underwent cardiac surgery during neonatal period., Design: Descriptive, ambispective., Setting: Neonatal Intensive Care Unit (NICU), Hospital de Pediatría, Centro Médico Nacional Siglo XXI., Patients: We studied 74 newborns with congenital heart defects who underwent corrective surgery, palliative surgery or interventional techniques and received preoperative and postoperative care in NICU. Premature patients with patent ductus arteriosus were excluded., Results: The following median values were found: birth weight was 2,862 g, gestational age was 39 weeks, onset of symptoms was 1 day, age at surgery was 14.5 days and postoperative hospital stay was 9 days. Most frequent congenital heart defects were single-ventricle, transposition of the great arteries and hypoplastic right heart. Fifty percent of surgeries were corrective, 46% were palliative and 4% were interventional techniques. Global survival was 51%, for curative surgery was 43% and for palliative surgery was 58%. Only 3 patients underwent interventional cardiology, 2 of them died (survival 33%)., Conclusions: Global survival in newborns who underwent cardiac surgery is lower in comparison with other studies. Survival is higher in children with palliative surgery in comparison with those who underwent corrective surgery.

Objective: To analyze an outbreak of Serratia marcescens in a neonatal intensive care unit and identify the risk factors associated to the development of infection., Material and Methods: It was a case-control study from March to July 1995. Factors included were age, sex, intravascular devices, nebulizers, mechanical ventilation, use of total parenteral nutrition (TPN), underlying diseases, surgical interventions, tubes, previous antimicrobial treatment and days of exposure. The associations were explored using the odds ratio., Results: 24 cases and 30 controls were included. In the univariate analysis the significant risk factors (OR,IC) were use of central venous catheter (4.57, 1.01-23.5), days of use of TPN (4.38, 1.03-16.5), days of previous antimicrobial treatment (4.87, 1.60-22) and days of exposure (2.7, 2.65-27.6). In the multivariate analysis the significant risk factors were previous antimicrobial treatment (3.98, 2.36-18.2), days of previous antimicrobial treatment (6.76, 3.02-24.6) and days of use of TPN (4.87, 1.67-15.6)., Conclusions: The significant risk factors in our study were previous antimicrobial treatment, days of antimicrobial and days of use of TPN.

We analyzed 56 cases of children with diagnosis of poisoning, which were attendant at the pediatric emergency room at "Dr. Manuel Gea Gonzalez" General Hospital, during a period between October 1st 1987 and September 31st, 1988. A greater incidence among infants below 5 years of age was observed, 16.07% of these were newborn infants. Male infants were the most affected. The most frequent causes were iatrogenic and accidental incidents. Only 4 cases of suicide attempt was reported. Medically prescribed drugs were the most frequent cause of poisoning. Of these, anticholinergic agents were the number one cause. Among other types of agents, a relatively high incidence of mushroom poisoning was observed. General death rate was 10.71%. Through a survey answered by 400 physicians, we studied their knowledge of basic concepts of toxicology, commercial names, doses and side effects of certain drugs; 24% of these were pediatricians, and the rest were general physicians. This survey reveals adequate knowledge of commercial names of drugs, but poor knowledge of basic toxicology, doses and side effects of these drugs.