Mexican Institute of Social Security
Recent publications
Childhood obesity predicts adult obesity and may increase the lifetime risk of adverse health outcomes. Obesity is characterized by oxidative stress that can induce DNA damage; however, studies of childhood and adolescent obesity are scarce. We investigated DNA damage due to obesity in Mexican children using the chromatin dispersion test (CDT). We evaluated DNA damage to peripheral lymphocytes of 32 children grouped according to body mass index as normal weight (controls), overweight and obese groups using guidelines from the Centers for Disease Control (CDC). We found that the greatest DNA damage occurred in cells of obese children compared to normal weight and overweight children. Our findings support preventive action to obviate adverse health outcomes due to obesity.
Objectives We aim to quantify shifts in hospitalisation and mortality and how those were related to the first three phases of the epidemic and individuals’ demographics and health profile among those with a positive test for SARS-CoV-2 treated at the Mexican Social Security Institute’s facilities from March 2020 to October 2021. Design Retrospective observational study using interrupted time series analysis to identify changes in hospitalisation rate and case fatality rate (CFR) by epidemic wave. Setting Data from the Mexican Institute of Social Security’s (IMSS) Online Influenza Epidemiological Surveillance System (SINOLAVE) that include all individuals that sought care at IMSS facilities all over Mexico. Participants All individuals included in the SINOLAVE with a positive PCR or rapid test for SARS-CoV-2. Primary and secondary outcome measures Monthly test positivity rates, hospitalisation rates, CFRs and prevalence of relevant comorbidities by age group. Results From March 2020 to October 2021, the CFR declined between 1% and 3.5%; the declines were significant for those 0–9, 20–29, 30–39, 40–49 and 70 and older. The decline was steep during the first wave and was less steep or was temporarily reversed at the beginning of the second and third waves (changes in the trend of about 0.3% and 3.8%, and between 0.7% and 3.8%, respectively, for some age groups), but then continued to the end of the analytical period. Prevalence of diabetes, hypertension and obesity among patients testing positive also declined—two for most age groups (reductions of up to 10 percentage points for diabetes, 12 percentage points for hypertension and 19 percentage points for obesity). Conclusion Data suggest that the decrease in COVID-19 fatality rate is at least partially explained by a change in the profile of those contracting the disease, that is, a falling proportion of individuals with comorbidities across all age groups.
Introducción: el síndrome de burnout (SBO) y el riesgo elevado de burnout (REBO) representan un riesgo latente en los medicos anestesiólogos, exacerbado por la pandemia Covid-19, esto, debido a la sobrecarga de trabajo, estrés laboral y miedo al contagio entro otros factores. El Maslach Burnout Inventory (MBI) es un instrumento para el diagnóstico, evalúa tres subescalas: despersonalización, desgaste emocional, realización personal. Material y métodos: estudio de encuestas realizados a los medicos adscritos y residentes del servicio de anestesiología del Hospital de Especialidades “La Raza”. La confiabilidad de los ítems del instrumento se realizó mediante el cálculo de alfa de Cronbach. Se construyeron varios modelos de regresión logística para explorar los posibles factores de riesgo para las diferentes sub escalas, SBO y REBO. Resultados: del total de la muestra (N=101) el SBO presento una prevalencia del 18.8% y el REBO de 25.7%. En el analisis univariado para subescala desgaste emocional; TAC OR 1.16, IC95% 0.96 - 1.39, p = 0.10 y UCPC OR 1.14, IC95% 0.9 - 1.43, p = 0.10 fueron significativos, pero, solo TAC OR 1.23, IC95% 1.01 - 1.5, p = 0.03 resulto significativo en modelo multivariado. No existió ninguna otra significancia en los demos modelos (SBO, REBO). Existe buena confiabilidad para las diferentes subescalas de MBI. Conclusión: existe una prevalencia media de REBO en comparación con el SBO (25.7% vs 18.8%) respectivamente.
Objectives: Exosomes are the smallest of the extracellular vesicles and can contain a variety of different cargos, including nucleic acids, lipids, and proteins. Ultracentrifugation followed by electron microscopy has historically been used for the isolation and visualization of exosomes; Western blot and ELISA have also been used, but these techniques are only semiquantitative and are unable to distinguish different exosome markers in the same sample. To resolve some of these issues, we propose a modification of a bead-based flow cytometry method. Methods: Peripheral blood serum was mixed with a commercial exosome separation reagent and incubated for 30 min at 4°, centrifuged, exosome pellet was isolated and resuspended in PBS. Exosomes were then added to magnetic beads, incubated 18 h, then incubated with exosome-specific antibodies for 1 h. The resulting bead:exosome complexes were centrifuged and then washed, then washed again using a magnetic separator, resuspended in PBS, and analyzed via flow cytometry. Results: Using commercial magnetic beads bound with anti-CD63, our protocol modifies starting conditions, washing steps, and magnetic separation and uses the FSC and SSC determination of the flow cytometer to result in increased yield and identification of the exosome populations of interest. Our modified protocol increased the yield of specific populations approximately 10-fold. Conclusion: The new protocol was used to identify exosomes positive for 2 immune checkpoint ligands in serum-derived exosomes from cervical cancer patients. We suspect that this protocol can also be used for the identification of other exosome proteins since we also quantified the exosome membrane-enriched tetraspanins CD9 and CD81. Identification of proteins rarely expressed in exosomes is complicated in this technique as serum is an inherently dirty source of exosomes, and great care must be taken in the washing and gating of the exosome:bead populations.
The aims of this study were in systemic lupus erythematosus (SLE) patients: 1) to compare the metabolomic profile of insulin resistance (IR) with controls and 2) to correlate the metabolomic profile with other IR surrogates and SLE disease variables and vitamin levels. In this cross-sectional study, serum samples were collected from women with SLE (n= 64) and gender- and age-matched controls (n= 71), which were not diabetic. Serum metabolomic profiling was performed using UPLC-MS-MS (Quantse score). HOMA and QUICKI were carried out. Serum 25(OH)D concentrations were measured by chemiluminescent immunoassay. In women with SLE, the metabolomic Quantose score significantly correlated with HOMA-IR, HOMA2-IR, and QUICKI. Although concentrations of IR metabolites were not different between SLE patients and controls, fasting plasma insulin levels were higher and insulin sensitivity lower in SLE women. Interestingly, the Quantose IR score was significantly correlated with complement C3 levels (r= 0.7; p= 0.001). 25 (OH)D did not correlate with any metabolite or the Quantose IR index. Quantose IR may be a useful tool for IR assessment. There was a possible correlation between the metabolomic profile and complement C3 levels. The implementation of this metabolic strategy may help develop biochemical insight into metabolic disorders in SLE.
There is still a need for safe, efficient, and low-cost coronavirus disease 2019 (COVID-19) vaccines that can stop transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Here we evaluated a vaccine candidate based on a live recombinant Newcastle disease virus (NDV) that expresses a stable version of the spike protein in infected cells as well as on the surface of the viral particle (AVX/COVID-12-HEXAPRO, also known as NDV-HXP-S). This vaccine candidate can be grown in embryonated eggs at a low cost, similar to influenza virus vaccines, and it can also be administered intranasally, potentially to induce mucosal immunity. We evaluated this vaccine candidate in prime-boost regimens via intramuscular, intranasal, or intranasal followed by intramuscular routes in an open-label non-randomized non-placebo-controlled phase I clinical trial in Mexico in 91 volunteers. The primary objective of the trial was to assess vaccine safety, and the secondary objective was to determine the immunogenicity of the different vaccine regimens. In the interim analysis reported here, the vaccine was found to be safe, and the higher doses tested were found to be immunogenic when given intramuscularly or intranasally followed by intramuscular administration, providing the basis for further clinical development of the vaccine candidate. The study is registered under identifier NCT04871737.
Background: Distal radius fractures are very frequent fractures in the world, so it is necessary to establish new rehabilitation strategies. Objective: To determine the effectiveness of tele rehabilitation versus supervised treatment in the functional recovery of patients with distal radius fracture. Method: A randomized clinical trial was conducted that included 91 patients with distal radius fractures grades AO23 A and AO23B, which were randomly assigned to a treatment group, the supervised rehabilitation group received for two weeks a program of 10 treatment sessions and the tele rehabilitation group received through the Moodle platform instructions to carry out the rehabilitation program. Outcome measures (functionality, active range of motion, hand grip strength, quality of life and pain) were measured at the time of admission to rehabilitation and at 1, 3 and 6 months. Results: In both treatment groups at 6 months, statistically significant intragroup differences in functionality were demonstrated, with no intergroup differences. Conclusions: At 6 months, both rehabilitation programs increase functionality, range of motion, quality of life and decrease pain, without statistically significant differences intergroup.
Background: Cryptococcosis is the most common mycosis of the central nervous system. It may develop in immunocompetent and immunocompromised patients, the latter representing most cases. The most common presentation of the disease is meningitis, whereas intra-axial lesions in the form of cryptococcoma are less frequent with a greater tendency to present in immunocompetent patients. The presentation of pituitary cryptococcoma is exceptional. To the best of the authors' knowledge, there is only one case published in the medical literature. Observations: The authors present the case of a 30-year-old male without a relevant medical history. He was referred to our center with a pituitary mass on magnetic resonance imaging and panhypopituitarism. The patient underwent endonasal endoscopic transsphenoidal tumor resection, and a histopathological diagnosis of pituitary cryptococcoma was made. Medical management included fluconazole and intravenous amphotericin. Lessons: This case underscores the neurosurgical and medical management of an exceptional clinical presentation of pituitary cryptococcoma in an immunocompetent patient. To the best of the authors' knowledge, there is only one case published in the medical literature. This case provides an invaluable review of the clinical, imaging, and therapeutic considerations regarding this exceptional clinical entity.
Objetivo. Determinar la vacunación como factor protector para hospitalización en paciente con COVID-19 en la cuarta ola de la pandemia. Métodos. Diseño de cohorte retrospectiva en pacientes con COVID-19 durante la cuarta ola (1 enero a 9 febrero de 2022). Grupos expuestos, antecedente de vacuna anti COVID-19 (vacuna de adenovirus modificado genéticamente y vacuna de ácido ribonucleico mensajero), grupo no expuestos, no vacuna. Tamaño de muestra todos los casos del periodo, grupo expuesto (vacuna de adenovirus modificados genéticamente, n=41; vacuna de ácido ribonucleico mensajero, n=105; y grupo no expuesto, n=263. Análisis estadístico, chi cuadrada, riesgo relativo, regresión logística múltiple y cálculo de probabilidad de ocurrencia del evento. Resultados. En una mujer entre 50 y 59 años que no tiene enfermedad crónica degenerativa y que recibió vacuna de adenovirus modificado genéticamente, la probabilidad de hospitalización si presenta COVID-19 es 34,5%; si recibió vacuna de acido ribonucleico mensajero la probabilidad de hospitalización es 1,7% y si no recibió vacuna la probabilidad de hospitalización varía entre 56,6% y 58,9%. Esta misma mujer si presenta enfermedad crónica degenerativa la probabilidad de hospitalización es 50,3% con vacuna de adenovirus modificado genéticamente, 4,4% con vacuna de ácido ribonucleico mensajero, y varía entre 73,4% y 77,2% si no recibió vacuna. Conclusiones. La vacuna anti COVID-19 es un factor protector para hospitalización en pacientes que presentan cuadro agudo de COVID-19.
Objetivo: Identificar la asociación entre obesidad y síntomas de depresión en adolescentes atendidos en una unidad de salud familiar. Materiales y Métodos: Estudio observacional, transversal comparativo en adolescentes mexicanos de 10 a 19 años, se integraron dos grupos de comparación, adolescentes con obesidad y sin obesidad. El tamaño de la muestra fue de 97 adolescentes por cada grupo, se empleó muestreo no probabilístico por cuota. La depresión se evaluó con la versión revisada de la Escala de Depresión del Centro de Estudios Epidemiológicos (CESD-R). El análisis estadístico incluyó promedios, porcentajes, desviaciones estándar, prueba chi cuadrado, razón de momios (RM), e intervalos de confianza para RM. Resultados: En el grupo de adolescentes con obesidad 48,5% presentaron síntomas depresivos y en el grupo de adolescentes sin obesidad 33% también presentaron síntomas depresivos (p=0,02), RM de 1,90 (IC 95%: 1,06-3,41). Conclusiones: Se encontró asociación entre obesidad y síntomas de depresión en adolescentes.
This study aimed to analyze the biochemical, histological, and gene expression alterations produced in a hepatocarcinogenesis model induced by the chronic administration of diethylnitrosamine (DEN) and 2-acetylaminofluorene (2-AAF) in Wistar rats. Thirteen rats weighing 180 to 200 g were divided into two groups: control and treated. Rats in the treated group were administered an intraperitoneal (i.p.) injection of DEN (50 mg/kg/week) and an intragastric (i.g.) dose of 2-AAF (25 mg/kg/week) for 18 weeks. The treated group had significant increases in their total cholesterol, HDL-C, AST, ALT, ALKP, and GGT levels. Furthermore, a histological analysis showed the loss of normal liver architecture with nuclear pleomorphism in the hepatocytes, atypical mitosis, and fibrous septa that were distributed between the portal triads and collagen fibers through the hepatic sinusoids. The gene expressions of 24 genes related to fibrosis, inflammation, apoptosis, cell growth, angiogenesis, lipid metabolism, and alpha-fetoprotein (AFP) were analyzed; only TGFβ, COL1α1, CYP2E1, CAT, SOD, IL6, TNF-α, and ALB showed significant differences when both groups were compared. Additionally, lung histopathological alterations were found in the treated group, suggesting metastasis. In this model, the chronic administration of DEN+2-AAF induces characteristic alterations of hepatocellular carcinoma in Wistar rats without AFP gene expression changes, highlighting different signatures in hepatocellular carcinoma heterogeneity.
Dementia is a multifactorial disease in which environmental, lifestyle, and genetic factors intervene. Population studies have been used in looking for the susceptibility genes for this disease. Since the activity of dopamine b hydroxylase (DβH) is reduced in the hippocampus and neocortex in the brain, changes in the physiological status of dopamine have been reported in Alzheimer’s disease (AD) induced by this enzyme. Therefore, DBH polymorphisms have been associated with susceptibility to some neurological diseases such as AD, but few studies have investigated the relationship between these polymorphisms with other types of dementia, especially in Mexican populations. The aim of this study was to evaluate the association between single-nucleotide polymorphism (SNP) in the dopamine b-hydroxylase (DBH gene (rs1611115) and their interactions with environmental factors and the dementia risk. We examined the genotype of the gene DBH (rs1611115) polymorphism in patients with dementia and healthy. The interaction and the impact of DBH (rs1611115) polymorphism on dementia were examined through multifactor dimensionality reduction (MDR) analysis, and the results were verified by the Chi-square test. Hardy–Weinberg equilibrium (HWE) was also checked by the Chi-square test. The relative risk was expressed by odds ratio (OR) and 95%. A total of 221 dementia patients and 534 controls met the inclusion criteria of MDR analyses. The results of the MDR analysis showed that the development of dementia was positively correlated with interaction between the TT genotype of the DBH1 locus rs1611115 TT and diabetes, hypertension, and alcohol consumption (OR = 6.5: 95% CI = 4.5–9.5), originating further cognitive damage. These findings provide insight into the positive correlation between the metabolism and cardiovascular disorders and the presence of the T allele by means of a recessive model of DBH rs1611115 polymorphism with the suspensibility of dementia.
Infection of epithelial cells with high-risk HPV (HR-HPV) types, followed by expression of virus oncogenic proteins (E5, E6, and E7), leads to genomic imbalance, suppression of tumor inhibitors, and induction of oncogenes. Low-risk HPV (LR-HPV) may slow the rate at which cervical cancer spreads to an invasive stage since co-infection with LR-HPV is linked to a decreased risk of future invasive cancer than infection with HR-HPV alone. We then propose that cancer-progressing changes may be distinguished through identifying the functional differences between LR-HPV and HR-HPV. Lentiviral strategies were followed to establish HaCaT cells with constitutive expression of HPV oncogenes. RNAseq experiments were designed to analyze the transcriptome modulations caused by each of the E5, E6, and E7 oncogenes of HPV-16 and HPV-84 in HaCaT cells. We identified enhanced RNA degradation, spliceosome, and RNA polymerase pathways related to mRNA processing. ATTS (alternative transcription termination site) was discovered to be more prevalent in cells with HPV-16E5 than HPV-84E5. In HPV-16E6-infected cells, ATTS gain was significantly higher than ATTS loss. Cells with HPV-16E7 had more isoforms with intron retention (IR) than those with HPV-84E7. We identified switches in ADAM10, CLSPN, and RNPS1 that led to greater expression of the coding isoforms in HR-HPV. The results of this work highlight differences between LR-HPV and HR-HPV in mRNA processing. Moreover, crucial cervical cancer-related switch events were detected.
Background Previously, we reported lower RSK4 mRNA and protein levels in malignant ovarian tumors compared to normal and benign ovarian tissues. Also, we observed a significant inverse correlation between the advanced ovarian cancer stages and RSK4 mRNA levels. We did not investigate the mechanisms involved in RSK4-reduced expression in ovarian cancer. Thus, this study investigates whether RSK4 promoter methylation in ovarian cancer tissues is responsible for its low expression. Additionally, the reactivation of RSK4 expression and its effect was studied in ovarian cancer cell lines. Methods and results RSK4 promoter methylation percentage in malignant and benign ovarian tumors and normal ovary tissues was determined by combined bisulfite restriction analysis. The reactivation of RSK4 expression by decitabine treatment was studied in OVCAR3, SKOV3, TOV-112D, and TOV-21G cells by Western blotting. Cell proliferation was determined by XTT. A significantly high methylation percentage of the RSK4 promoter was observed among malignant and benign ovarian tumors but not in normal ovarian tissue. RSK4 promoter methylation was not associated with age, histological subtype, or stages of ovarian cancer. RSK4 promoter methylation correlates weakly but not significantly with RSK4 protein expression. No correlation was shown between RSK4 methylation and RSK4 mRNA expression. Decitabine induces RSK4 reactivation in all cell lines. However, cell proliferation was reduced only in TOV-112D cells. Conclusion These data indicate that although RSK4 promoter methylation is increased in malignant ovarian tumors, this mechanism is unlikely to regulate its expression in ovarian cancer. RSK4 reactivation reduced cell proliferation only in the endometroid histological subtype.
Objectives: The aim of this study was thus to evaluate the effect of Cr supplementation on morphological changes and expression of pro-inflammatory cytokines in the hippocampus and on developmental parameters. Methods: Male Wistar rat pups were submitted to an experimental model of CP. Cr was administered via gavage from the 21st to the 28th postnatal day, and in water after the 28th, until the end of the experiment. Body weight (BW), food consumption (FC), muscle strength, and locomotion were evaluated. Expression of interleukin-1β (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor α (TNF-α) were assessed in the hippocampus by quantitative real-time polymerase chain reaction. Iba1 immunoreactivity was assessed by immunocytochemistry in the hippocampal hilus. Results: Experimental CP caused increased density and activation of microglial cells, and overexpression of IL-6. The rats with CP also presented abnormal BW development and impairment of strength and locomotion. Cr supplementation was able to reverse the overexpression of IL-6 in the hippocampus and mitigate the impairments observed in BW, strength, and locomotion. Discussion: Future studies should evaluate other neurobiological characteristics, including changes in neural precursor cells and other cytokines, both pro- and anti-inflammatory.
Introduction: Peritoneal dialysis (PD) guidelines recommend a 14-day break-in period after catheter placement, yet this period could be shortened with new insertion techniques. Methods: We conducted a prospective cohort study to compare percutaneous vs. surgical catheter insertion in a newly established PD program. The break-in period was intentionally shortened to <24 h to start PD almost immediately. Results: We included 223 subjects who underwent percutaneous (34%) or surgical (66%) catheter placement. Compared to the surgical group, the percutaneous group had a higher proportion of early dialysis initiation within 24 h (97% vs. 8%, p < 0.001), similar successful initiation rates (87% vs. 92%, p = 0.34), and shorter lengths of stay (12 [9-18] vs. 18 [14-22] days, p < 0.001). Percutaneous insertion increased the likelihood of successful PD initiation within 24 h (OR 74, 95% CI 31-182), without increasing major complications. Conclusion: Percutaneous placement could represent a cost-effective and efficient technique to shorten break-in periods.
Background: The pathogenic model guides the study of risk factors for the disease; the salutogenic model guides the study of health assets, focused on problem solving, the ability of people to use their available resources and perceive their lives as coherent, structured and understandable. Its central element is the sense of coherence (SOC). The relationship of SOC with different phases of diabetes has been demonstrated, but not in diabetic debutants. Objective: To evaluate the magnitude of the association of SOC between type 2 diabetes mellitus (T2DM) debutants and absentees in people detected in the PREVENIMSS module. Material and methods: case-control design. Cases were T2DM debutants with fasting plasma glucose ≥ 126 mg/dL; controls, people with plasma glucose < 100 mg/dL. Sample size was estimated for independent groups (101 cases and 202 controls) in which the SOC-29 questionnaire was administered; socio-demographic data was recorded and their file was reviewed. Reliability of SOC-29 was analyzed; univariate analysis, chi-squared and binary logistic regression were used to estimate association and odds ratio (OR). Results: T2DM debutants were 5 times more likely to achieve a low SOC score than patients without T2DM (p = 0.002; OR: 5.31, 95% confidence interval: 1.81-15.53). Conclusions: High sense of coherence is an asset for the health of T2DM debutants; it is proposed to incorporate this topic into the DIABETIMSS program.
Background: Diabetic retinopathy is a progressive disfunction of blood vessels of the retina secondary to chronic hyperglycemia. There are several treatments, out of which panretinal photocoagulation (PRP) stands out. Objective: To compare the level of pain in patients undergoing PRP with different impulse. Material and methods: Comparative, cross-sectional study that compared the level of pain in patients undergoing PRP with a 50-millisecond pulse (group A) versus conventional 200 milliseconds pulse (group B). Mann-Whitney U test was used. Results: There were 26 patients, 12 (46.16%) female and 14 (53.84%) males. The median age was 58.73 ± 7.31 (40-75) years. 40 eyes were studied, 18 (45%) right and 22 (55%) left. The mean level of glycated hemoglobin was 8.15 ± 1.08 (6.5-12) %. The mean laser power was 297 ± 53.61 (200-380) and 214.5 ± 41.73 (170-320) milliwatts; the mean fluence was 18.85 ± 5.28 (12-28) J/cm2 and 65.9 ± 12.87 (52-98) J/cm2; the mean level of pain was 3.1 ± 1.33 (1-5) and 7.5 ± 1.23 (6-10) points for group A and B, respectively, and there was statistically significant difference (p ˂ 0.001) in the level of pain. There were no complications in any group. Conclusion: The application of retinal 50-millisecond pulse PRP causes less pain and side effects than 200-millisecond pulse PRP.
Background: acute pulmonary embolism (APE) is a complex and potentially deadly entity, with a variable clinical course, considered the third cardiovascular cause of death. Its management varies according to the stratified risk from anticoagulation to reperfusion therapy, suggesting systemic thrombolysis as a first-choice strategy; however, in a large group of patients their use will be contraindicated, discouraged or will have failed, thus recommending as options in such cases endovascular therapies or surgical embolectomy. With the presentation of 3 clinical cases and a review of the literature, we seek to communicate our initial experience in the use of ultrasound-accelerated thrombolysis with the EKOS system and to investigate key elements for its understanding and application. Clinical cases: the cases of 3 patients with APE of high and intermediate risk with contraindications for systemic thrombolysis taken to accelerated thrombolysis therapy by ultrasound are discussed. They presented adequate clinical and hemodynamic evolution in the short term, achieving a rapid decrease in thrombolysis, systolic and mean pulmonary arterial pressure, improvement of right ventricular function and reduction of thrombotic burden. Conclusion: Ultrasound-accelerated thrombolysis is a novel pharmaco-mechanical therapy that combines the emission of ultrasonic waves with the infusion of a local thrombolytic agent, a strategy that, according to different trials and clinical registries, has a high success rate and a good safety profile.
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1,910 members
Jose Guzman-Esquivel
  • Departament of Clinical Epidemiology Research
Guadalupe García-Elorriaga
  • External member of the Ethics Committee and research.
Maricruz Anaya
  • Centro de Investigación Biomedica de Oriente
Eunice López
  • Unidad de Investigación Médica en Medicina Reproductiva
Baldomero gonzalez virla
Mexico City, Mexico