Increased Frequency of Giant Miniature End-Plate Potentials at the Neuromuscular Junction in Diabetic Rats

There is a need for research addressing the functional characteristics of the motor end-plate in diabetes to identify mechanisms contributing to neuromuscular dysfunction. Here, we investigated the effect of diabetes on spontaneous acetylcholine release in the rat neuromuscular junction. We studied two randomized groups of male Wistar rats (n = 7 per group, 350 ± 50 g, 12-16 weeks of age): one with streptozotocin-induced experimental diabetes, and a healthy control group without diabetes. After 8 weeks of monitoring after diabetes induction, rats in both groups were anesthetized with pentobarbital. Then, the diaphragm muscle was dissected for electrophysiological recordings of miniature end-plate potentials (MEPPs) using a single electrode located at the region of the muscle end-plate. All experiments were conducted at environmental temperature (20-22 °C) in rat Ringer solution with constant bubbling carbogen (95% O2, 5% CO2). Compared to healthy controls, in the diaphragm neuromuscular end-plate derived from diabetic rats, the MEPPs were higher in amplitude and frequency, and the proportion of giant MEPPs was elevated (7.09% vs. 1.4% in controls). Our results showed that diabetes affected the acetylcholine MEPP pattern and increased the number of giant potentials compared to healthy controls.

Animal models of kidney iron overload and ferroptosis: a review of the literature

In recent years, it has been identified that excess iron contributes to the development of various pathologies and their complications. Kidney diseases do not escape the toxic effects of iron, and ferroptosis is identified as a pathophysiological mechanism that could be a therapeutic target to avoid damage or progression of kidney disease. Ferroptosis is cell death associated with iron-dependent oxidative stress. To study the effects of iron overload (IOL) in the kidney, numerous animal models have been developed. The methodological differences between these models should reflect the IOL-generating mechanisms associated with human IOL diseases. A careful choice of animal model should be considered for translational purposes.

Association between Vaccination Status for COVID-19 and the Risk of Severe Symptoms during the Endemic Phase of the Disease

The global health emergency caused by COVID-19 concluded in May 2023, marking the beginning of an endemic phase. This study aimed to evaluate the association between vaccination status and other patient characteristics and the risk of severe disease during this new endemic period. A nationwide cohort study was conducted in Mexico, where we analyzed data from 646 adults who had received positive confirmation of COVID-19 through PCR testing from May to August 2023. The overall risk of severe symptoms in the study sample was 5.3%. The average time elapsed from the last vaccine shot to symptom onset was over six months in all the immunized groups (1, 2 or 3 vaccine doses). Compared to unvaccinated patients, those with three vaccine doses showed an elevated risk of severe symptoms. Advancing age and various chronic comorbidities (specifically cardiovascular, kidney, and obstructive pulmonary conditions) were associated with a heightened risk of severe COVID-19 manifestations. These findings underscore the ongoing seriousness of COVID-19, even in an endemic phase, underscoring the urgent need for tailored interventions aimed at high-risk patients.

Survival Analysis and Contributing Factors among PCR-Confirmed Adult Inpatients during the Endemic Phase of COVID-19

In May 2023, the global health emergency status of COVID-19 concluded, marking the onset of an endemic era. This study assessed survival rates among PCR-confirmed adult inpatients during this phase and determined contributing factors. Employing a survival analysis approach, this investigation utilized a nationwide Mexican cohort encompassing 152 adult inpatients. Survival rates were computed using the Kaplan-Meier method, and a proportional Cox model identified mortality risk factors. Survival rates remained above 65% on day 14 after admission. Vaccination status, including the number of doses administered, was not significantly associated with fatal outcomes. Chronic kidney disease or a history of immunosuppression (due to any cause) increased mortality risk. Our findings underscore the persistent severity of COVID-19 beyond the global health emergency, emphasizing the necessity for tailored interventions for vulnerable patients.

Evaluating the performance of WHO and CDC case definitions for influenza-like illness in diagnosing influenza during the 2022-2023 flu season in Mexico

OBJECTIVE

This study aimed to evaluate the performance of the World Health Organization (WHO) and Centers for Disease Control and Prevention (CDC) case definitions for influenza-like illness (ILI) in diagnosing influenza during the 2022-2023 flu season in Mexico.

STUDY DESIGN

We conducted a cross-sectional analysis of national epidemiological surveillance data in Mexico, focusing on respiratory viral pathogens.

METHODS

We analyzed data from 6027 non-hospitalized patients between 5 and 65 years old who underwent molecular testing for respiratory viral pathogens. The performance of both case definitions was evaluated in terms of sensitivity, specificity, and the area under the receiver operating characteristic (AUROC) curve.

RESULTS

Overall, the diagnostic accuracy of the evaluated ILI definitions in identifying influenza patients was low, particularly among older patients. When compared to the CDC, the WHO definition had a lower sensitivity but a higher specificity, resulting in a higher AUROC (P = 0.031) for the WHO criteria.

CONCLUSIONS

Our findings suggest that the WHO and CDC ILI case definitions have limited accuracy for diagnosing influenza in non-hospitalized patients and highlight the need for more specific diagnostic tools to improve the detection of influenza cases during the flu season.

Assessing the relationship between energy-related methane emissions and the burden of cardiovascular diseases: a cross-sectional study of 73 countries

The energy industry significantly contributes to anthropogenic methane emissions, which add to global warming and have been linked to an increased risk of cardiovascular diseases (CVD). This study aims to evaluate the relationship between energy-related methane emissions and the burden of CVD, measured in disability-adjusted life years (DALYs), in 2019. We conducted a cross-sectional analysis of datasets from 73 countries across all continents. The analyzed datasets included information from 2019 on environmental energy-related methane emissions, burden of DALYs due to CVD. The age-standardized prevalence of obesity in adults and life expectancy at birth were retrieved. The relationship between the variables of interest was evaluated using multiple linear regression models. In the multiple model, we observed a positive linear association between methane emissions and the log-transformed count of DALYs related to CVD. Specifically, for each unit increase in energy-related methane emissions, the burden of CVD increased by 0.06% (95% CI 0.03-0.09%, p < 0.001). The study suggests that reducing methane emissions from the energy industry could improve public health for those at risk of CVD. Policymakers can use these findings to develop strategies to reduce methane emissions and protect public health.

Assessing the Influence of COVID-19 Vaccination Coverage on Excess Mortality across 178 Countries: A Cross-Sectional Study

The COVID-19 pandemic has had a devastating impact on global health, necessitating urgent and effective strategies to mitigate its consequences. Vaccination programs have been implemented worldwide to combat virus transmission and reduce the disease burden. This study aimed to investigate the relationship between COVID-19 vaccination coverage and all-cause excess mortality in 178 nations during the first two years of the pandemic. Multiple regression analysis, after adjusting for life expectancy at birth, confirmed a significant association between higher vaccination coverage and lower all-cause mortality rates (β = -106.8, 95% CI -175.4 to -38.2, p = 0.002). These findings underscore the importance of vaccination campaigns in reducing overall mortality during the COVID-19 pandemic. Evidence-based decision making and resource allocation can benefit from this information, facilitating the optimization of vaccination strategies for maximal impact on mortality reduction. Further research and continuous monitoring are crucial to understanding the long-term effects of vaccination coverage on population health in the ongoing pandemic.

Respiratory syncytial virus infection: survival experience in a cohort of children inpatients

OBJECTIVE

The objective of this study was to assess the survival experience of children hospitalized with laboratory-confirmed respiratory syncytial virus (RSV) infection due to bronchiolitis.

STUDY DESIGN

This was a nationwide retrospective cohort study conducted in Mexico.

METHODS

We analyzed data from 436 children aged 5 years and younger, with symptom onset between August 2021 and November 2022. The Kaplan-Meier method was used to compute survivor functions and their 95% confidence intervals (CI).

RESULTS

High survival rates were observed, particularly within the first three weeks of hospital admission. The 3-day survival rate was 99.8% (CI 98.4-99.9%), which decreased to 98.9% (CI 96.5-99.7%), 97.5% (CI 91.9-99.3%), 86.7% (CI 48.2-97.2%), and 69.4% (CI 24.2-91.0%) on days 7, 14, 21, and 28 of hospital stay, respectively. We documented a total of 5 fatal outcomes, resulting in a mortality rate of 2.1 (95% CI 0.9-5.1) per 1,000 person-days.

CONCLUSIONS

Our study analyzed a large cohort of pediatric patients with bronchiolitis caused by RSV infection, providing valuable insights into the in-hospital progression of this disease.

Assessing the Relationship between Annual Surface Temperature Changes and the Burden of Dengue: Implications for Climate Change and Global Health Outcomes

Dengue fever remains a significant global health concern, imposing a substantial burden on public health systems worldwide. Recent studies have suggested that climate change, specifically the increase in surface temperatures associated with global warming, may impact the transmission dynamics of dengue. This study aimed to assess the relationship between annual surface temperature changes from 1961 to 2019 and the burden of dengue in 185 countries. The dengue burden was evaluated for 2019 using disability-adjusted life years (DALYs) and the annual rate of change (ARC) in DALY rates assessed from 1990 to 2019. A cross-sectional and ecological analysis was conducted using two publicly available datasets. Regression coefficients (β) and 95% confidence intervals (CI) were used to examine the relationship between annual surface temperature changes and the burden of dengue. The results revealed a significant negative relationship between mean surface temperatures and DALY rates in 2019 (β = -16.9, 95% CI -26.9 to -6.8). Similarly, a significant negative relationship was observed between the temperature variable and the ARC (β = -0.99, 95% CI -1.66 to -0.32). These findings suggest that as temperatures continue to rise, the burden of dengue may globally decrease. The ecology of the vector and variations in seasons, precipitation patterns, and humidity levels may partially contribute to this phenomenon. Our study contributes to the expanding body of evidence regarding the potential implications of climate change for dengue dynamics. It emphasizes the critical importance of addressing climate change as a determinant of global health outcomes.

Assessing the Burden of Dengue during the COVID-19 Pandemic in Mexico

The transmission of the dengue virus in Mexico has historically been high, and its burden during the COVID-19 pandemic is currently not well understood. Our objective was to assess the burden of dengue-related disability-adjusted life years (DALYs) between 2020 and 2022. We conducted a cross-sectional analysis of databases resulting from an epidemiological surveillance of vector-borne diseases and computed DALYs using the protocol of the Global Burden of Disease (GBD) study 2019. Our results showed that there were 218,807 incident cases of dengue during the study period, resulting in 951 deaths. The calculated DALYs (and their 95% confidence intervals) were 8121 (7897-8396), 4733 (4661-4820), and 8461 (8344-8605) in 2020, 2021, and 2022, respectively. The DALY rates (per 100,000) were 6.5 (6.3-6.6), 3.8 (3.7-3.9), and 6.7 (6.6-6.8), respectively. The rates for 2020 and 2022 were similar to the historical mean (6.4, p = 0.884), whereas the rate for 2021 was lower than the mean. Premature mortality (years of life lost, YLL) contributed to 91% of the total burden. Our findings suggest that dengue fever remained a significant cause of disease burden during the COVID-19 pandemic, especially in terms of premature mortality.

Insight into the Burden of Malignant Respiratory Tumors and their Relationship with Smoking Rates and Lead Contamination in Mexico

We aimed to report the results from the Global Burden of Disease Study 2019 related to respiratory malignant tumors (tracheal, bronchial, and lung) in Mexico. We also evaluated the relationship between the burden of these neoplasms and the proportion of daily smokers and total lead emissions in 2019. A cross-sectional analysis of ecological data was performed. The burden of these tumors was 152,189 disability-adjusted life-years (DALYs), and years of life lost (YLL) contributed to 99% of them. The highest DALYs rates (per 100,000) were observed in the states of Sinaloa, Chihuahua, Baja California Sur, Sonora, and Nayarit. We documented a linear relationship between the DALYs rates and the prevalence of daily smokers (β = 8.50, 95% CI 1.58-15.38) and the total lead emissions (tons/year: β = 4.04, 95% CI 0.07-8.01). If later replicated, our study would provide insight into the major relevance of regulating tobacco use and the activities associated with the production of lead dust and other hazardous contaminants.

Capsaicin Decreases Kidney Iron Deposits and Increases Hepcidin Levels in Diabetic Rats with Iron Overload: A Preliminary Study

Iron overload (IOL) increases the risk of diabetes mellitus (DM). Capsaicin (CAP), an agonist of transient receptor potential vanilloid-1 (TRPV1), reduces the effects of IOL. We evaluated the effects of chronic CAP administration on hepcidin expression, kidney iron deposits, and urinary biomarkers in a male Wistar rat model with IOL and DM (DM-IOL). IOL was induced with oral administration of iron for 12 weeks and DM was induced with streptozotocin. Four groups were studied: Healthy, DM, DM-IOL, and DM-IOL + CAP (1 mg·kg^-1·day^-1 for 12 weeks). Iron deposits were visualized with Perls tissue staining and a colorimetric assay. Serum hepcidin levels were measured with an enzyme-linked immunosorbent assay. Kidney biomarkers were assayed in 24 h urine samples. In the DM-IOL + CAP group, the total area of iron deposits and the total iron content in kidneys were smaller than those observed in both untreated DM groups. CAP administration significantly increased hepcidin levels in the DM-IOL group. Urinary levels of albumin, cystatin C, and beta-2-microglobulin were similar in all three experimental groups. In conclusion, we showed that in a DM-IOL animal model, CAP reduced renal iron deposits and increased the level of circulating hepcidin.

COVID-19 Pneumonia in Fully Vaccinated Adults during the Dominance of the Omicron Sublineages BA.1.1 and BA.2 in Mexico

Background and Objectives: A nationwide retrospective cohort study was conducted to evaluate the factors associated with the risk of laboratory-confirmed coronavirus disease 2019 (COVID-19)-related pneumonia in fully vaccinated adults during the dominance of the Omicron sublineages in Mexico. Materials and Methods: Fully COVID-19-vaccinated adults with laboratory-positive illness and symptom onset from April to mid-June 2022 were eligible. We computed the eta-squared (η2) to evaluate the effect size of the study sample. The characteristics predicting pneumonia were evaluated through risk ratios (RRs), and the 95% confidence intervals (CIs) were computed through generalized linear models. Results: The data from 35,561 participants were evaluated, and the overall risk of pneumonia was 0.5%. In multiple analyses, patients aged ≥ 60 years old were at increased risk of developing pneumonia (vs. 20−39 years old: RR = 1.031, 95% CI = 1.027−1.034). Chronic pulmonary obstructive disease, type 2 diabetes mellitus, arterial hypertension, chronic kidney disease (any stage), and immunosuppression (any cause) were also associated with a higher pneumonia risk. The η2 of all the variables included in the multiple models was <0.06. Conclusions: Our study suggests that, even when fully COVID-19-vaccinated, older adults and those with chronic conditions were at increased risk of pneumonia during the dominance of the Omicron sublineages BA.1.1 and BA.2.

Activation of Peripheral Cannabinoid Receptors Synergizes the Effect of Systemic Ibuprofen in a Pain Model in Rat

Pharmacological synergism is a current strategy for the treatment of pain. However, few studies have been explored to provide evidence of the possible synergism between a non-steroidal anti-inflammatory drug (NSAID) and a cannabinoid agonist, in order to establish which combinations might be effective to manage pain. The aim of this study was to explore the synergism between ibuprofen (IBU) and the synthetic cannabinoid WIN 55,212-2 (WIN) to improve pain relief by analyzing the degree of participation of the CB₁ and CB₂ cannabinoid receptors in the possible antinociceptive synergism using an experimental model of pain in Wistar rats. First, the effective dose thirty (ED₃₀) of IBU (10, 40, 80, and 160 mg/kg, subcutaneous) and WIN (3, 10, and 30 µg/p, intraplantar) were evaluated in the formalin test. Then, the constant ratio method was used to calculate the doses of IBU and WIN to be administered in combination (COMB) to determine the possible synergism using the isobolographic method. The participation of the CB₁ and CB₂ receptors was explored in the presence of the antagonists AM281 and AM630, respectively. The combination of these drugs produced a supra-additive response with an interaction index of 0.13. In addition, AM281 and AM630 antagonists reversed the synergistic effect in 45% and 76%, respectively, suggesting that both cannabinoid receptors are involved in this synergism, with peripheral receptors playing a relevant role. In conclusion, the combination of IBU + WIN synergism is mainly mediated by the participation of the CB₂ receptor, which can be a good option for the better management of pain relief.

Decreased survival in children inpatients with COVID-19 and antibiotic prescription

Background

The empirical prescription of antibiotics to inpatients with Coronavirus Disease 2019 (COVID-19) is frequent despite uncommon bacterial coinfections. Current knowledge of the effect of antibiotics on the survival of hospitalized children with COVID-19 is limited.

Objective

To characterize the survival experience of children with laboratory-positive COVID-19 in whom antibiotics were prescribed at hospital admission.

Methods

A retrospective cohort study was conducted in Mexico, with children hospitalized due to COVID-19 from March 2020 to December 2021. Data from 1601 patients were analyzed using the Kaplan–Meier method and the log-rank test. We computed hazard ratios (HR) and 95% confidence intervals (CI) to evaluate the effect of the analyzed exposures on disease outcomes.

Results

Antibiotics were prescribed to 13.2% (\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$n$$\end{document}n = 211) of enrolled children and a higher mortality rate [14.9 (95% CI 10.1–19.8) vs. 8.3 (95% CI 6.8–9.8)] per 1000 person-days, \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$p$$\end{document}p < 0.001) was found among them. At any given cut-off, survival functions were lower in antibiotic-positive inpatients (\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$p$$\end{document}p < 0.001). In the multiple model, antibiotic prescription was associated with a 50% increase in the risk of fatal outcome (HR = 1.50, 95% CI 1.01–2.22). A longer interval between illness onset and healthcare-seeking and pneumonia at hospital admission was associated with a poorer prognosis.

Conclusions

Our results suggest that antibiotic prescription in children hospitalized due to COVID-19 is associated with decreased survival. If later replicated, these findings highlight the need for rational antibiotics in these patients.

Empirical Antibiotic Prescribing in Adult COVID-19 Inpatients over Two Years in Mexico

Background and Objectives: Empirical antibiotic prescribing in patients with coronavirus disease 2019 (COVID-19) has been common even though bacterial coinfections are infrequent. The overuse of antibacterial agents may accelerate the antibiotic resistance crisis. We aimed to evaluate factors predicting empirical antibiotic prescribing to adult COVID-19 inpatients over 2 years (March 2020–February 2021) in Mexico. Materials and Methods: A cross-sectional analysis of a nationwide cohort study was conducted. Hospitalized adults due to laboratory-confirmed COVID-19 were included (n = 214,171). Odds ratios (OR) and 95% confidence intervals (CI), computed by using logistic regression models, were used to evaluate factors predicting empirical antibiotic prescribing. Results: The overall frequency of antibiotic usage was 25.3%. In multiple analysis, the highest risk of antibiotic prescription was documented among patients with pneumonia at hospital admission (OR = 2.20, 95% CI 2.16–2.25). Male patients, those with chronic comorbidities (namely obesity and chronic kidney disease) and longer interval days from symptoms onset to healthcare seeking, were also more likely to receive these drugs. We also documented that, per each elapsed week during the study period, the odds of receiving antibiotic therapy decreased by about 2% (OR = 0.98, 95% CI 0.97–0.99). Conclusion: Our study identified COVID-19 populations at increased risk of receiving empirical antibiotic therapy during the first two years of the pandemic.

Impact on the Nutritional and Functional Status of Older Mexican Adults in the Absence of Recreational Activities due to COVID-19: A Longitudinal Study From 2018 to 2021

A longitudinal study, from 2018 to 2021, identified impacts on the nutritional and functional status of older adults when face-to-face activities at a social assistance center in Mexico were suspended due to the COVID-19 pandemic. A total of 71 older adults were evaluated at three different periods: 18 months prior, three months before the pandemic, and 12 months after the onset of the pandemic. Seventy-one older adults completed follow up. Anthropometric measurements, dietary intake, physical tests, and health screening for malnutrition, dependence, and physical frailty, were evaluated. There was a significant decrease in lean body mass and body water in the older adults assessed, in addition to a significant reduction in the frailty scale and gait speed. Finally, a significant reduction in ingested energy and several nutrients such as protein, and carbohydrates, was found, yet an increase in sugar and cholesterol intake was noted.

COVID-19 vaccines provide better protection against related pneumonia than previous symptomatic infection

Objectives

To compare, in a real-world scenario, the protective effect of vaccination and previous laboratory-confirmed symptomatic infection on the risk of COVID-19 pneumonia.

Methods

A retrospective study was conducted and 46,998 adults with laboratory-confirmed COVID-19 were enrolled. Risk ratios (RRs) and 95% confidence intervals (CIs) were used to evaluate the effect of the evaluated exposures on the risk of pneumonia.

Results

In multiple analysis and after adjusting by reinfection status, vaccinated participants were at reduced risk of developing pneumonia (RR = 0.974, 95% CI 0.965–0.983). The association of having had a previous infection was not significant (RR = 1.001, 95% CI 0.969–1.034).

Conclusion

Our results suggest, and if later replicated, that COVID-19 vaccines provide better protection against pneumonia than previous symptomatic infections. Therefore, offering vaccination to all eligible subjects despite past COVID-19 infections might be relevant to reducing the pandemic-related burden.

Decreased risk of COVID-19 pneumonia in children and adolescents during the Delta variant emergence

Objectives

This study aimed to evaluate factors associated with the risk of COVID-19 pneumonia in children (aged <10 years) and adolescents (aged 10–19 years) before (March 2020–April 2021) and during (May–July 2021) the Delta (B.1.617.2) variant emergence.

Study design

A retrospective and nationwide cohort study was conducted in Mexico.

Methods

Data from 26,961 laboratory-confirmed cases of COVID-19 were analyzed. Risk ratios (RRs) and 95% confidence intervals (CIs) were used to evaluate the association of the evaluated exposures with the risk of COVID-19 pneumonia.

Results

The overall incidence rate of pneumonia was 23.0 per 10,000 person-days, and it was lower during the Delta variant emergence (30.3 vs. 9.4 person-days, p < 0.001). In multiple analysis, a decreased risk of pneumonia was observed among those cases occurring in May 2021 or later (vs. March 2020–April 2021, RR = 0.98, 95% CI 0.97–0.99) and among older patients (RR_{per year} = 0.998, 95% CI 0.996–0.998). Other comorbidities (namely, obesity, chronic kidney disease, diabetes mellitus, immunosuppression, or malignant tumors) were associated with an increased risk of severe COVID-19 manifestations.

Conclusions

Our findings suggest that during the Delta variant emergence, children and adolescent patients were at reduced risk of COVID-19 pneumonia in Mexico. Further research is needed to identify factors determining the observed scenario.

Independent risk factors of COVID-19 pneumonia in vaccinated Mexican adults

Objectives

To evaluate host factors associated with the risk of coronavirus disease 2019 (COVID-19) pneumonia in vaccinated adults.

Methods

A cohort study was conducted in Mexico, and data from 1607 adults with confirmed illness, with a positive history of COVID-19 vaccination, were analyzed. Risk ratios (RR) and 95% confidence intervals (CI) were computed as a measure of the significance of the associations between putative risk factors and the prevalence of COVID-19 pneumonia in vaccinated subjects.

Results

The overall risk of pneumonia was 1.98 per 1000 person-days. In the multiple regression analysis, older subjects, those with a history of smoking (current), obesity, and type 2 diabetes mellitus were at increased risk of pneumonia.

Conclusions

Our results suggest that the effectiveness of COVID-19 vaccines may be reduced in a subset of adults who are older aged, smokers, obese, or have type 2 diabetes mellitus.

Alterations in blink and masseter reflex latencies in older adults with neurocognitive disorder and/or diabetes mellitus

BACKGROUND

Blink and masseter reflexes provide reliable, quantifiable data on the function of the central nervous system: Delayed latencies have been found in patients with neurocognitive disorder (ND) and type 2 diabetes mellitus (T2DM), but this has not been studied in patients with both pathologies.

AIM

To investigate if older adults with ND plus T2DM have prolonged latencies of blink and masseter-reflex and if they were associated with disease progression.

METHODS

This cross-sectional study included 227 older adults (> 60 years) from Colima, Mexico. Neurocognitive disorder was identified by a neuropsychological battery test, and T2DM identified by medical history, fasting glucose, and glycosylated hemoglobin. Latencies in the early reflex (R1), ipsilateral late (R2), and contralateral late (R2c) components of the blink reflex were analyzed for all subjects, and 183 subjects were analyzed for latency of the masseter reflex.

RESULTS

In 20.7% of participants, ND was detected. In 37%, T2DM was detected. Latencies in R1, R2, and R2c were significantly prolonged for groups with ND plus T2DM, ND, and T2DM, compared with the control group (P < 0.0001). The masseter reflex was only prolonged in older adults (regardless of T2DM status) with ND vs controls (P = 0.030). In older adults with ND and without T2DM, the more the cognitive impairment progressed, the more prolonged latencies in R2 and R2c presented (P < 0.01).

CONCLUSION

These findings suggest that blink and masseter reflexes could be used to evaluate possible changes in brainstem circuits in older adults with ND and T2DM.

Survival in influenza virus-related pneumonia by viral subtype: 2016-2020

BACKGROUND

Influenza remains a common cause of morbidity and mortality worldwide, and viral subtype-related differences in disease outcomes have been documented.

OBJECTIVE

To characterize the survival experience of adult inpatients with influenza virus-associated pneumonia by viral subtype during five consecutive flu seasons.

METHOD

We performed a retrospective cohort study; data from 4,678 adults were analyzed using the Kaplan-Meier method. A multivariate Cox proportional hazard regression model was fitted.

RESULTS

The overall in-hospital mortality rate was 25.0 per 1,000 hospital days. The survival probabilities from pneumonia patients went from 93.4% (95% CI 92.6-94.1%) by day three to 43.3% (95% CI 39.2-47.4%) by day 30 from hospital admission. In general, the lowest survival rates were observed in patients with AH1N1 infection. In multiple models, after adjusting for comorbidities and when compared with A non-subtyped virus, pneumonia patients with AH3N2 or B strains had a significantly decreased risk of a non-favorable disease outcome. The association of other strains was not significant.

CONCLUSIONS

Our findings suggest that the survival of inpatients with influenza virus-associated pneumonia varies according to the pathogenic viral subtype; the lowest survival rates were observed in patients with AH1N1 infection. This effect was independent of the patients' gender, age, and the analyzed underlying health conditions.

Symptomatic SARS-COV-2 reinfection: healthcare workers and immunosuppressed individuals at high risk

Background

Knowledge regarding factors predicting the SARS-COV-2 reinfection risk is scarce and it has major implications in public health policies. We aimed to identify factors associated with the risk of symptomatic SARS-COV-2 reinfection.

Methods

We conducted a nationwide retrospective cohort study and 99,993 confirmed cases of COVID-19 were analyzed.

Results

The overall risk of reinfection (28 or more elapsed days between both episodes onset) was 0.21% (incidence density, 2.5 reinfections per 100,000 person-days) and older subjects and those with the mild primary disease were at reduced risk of the event. Healthcare workers and immunosuppressed or renal patients had at greater risk of SARS-COV-2 reinfection.

Conclusions

If replicated in other populations, these results may be useful to prioritize efforts focusing on the reduction of SARS-COV-2 spread and the related burden.

Performance of Antigen-Based Testing as Frontline Diagnosis of Symptomatic COVID-19

Background and Objectives: To evaluate the performance of antigen-based detection tests as the frontline diagnosis of coronavirus disease 2019 (COVID-19). Materials and Methods: We conducted a nationwide retrospective cohort study in Mexico. A cross-sectional analysis of a cohort study was conducted in Mexico and data from 15,408 suspected (all of them symptomatic) cases of COVID-19 were analyzed. The results of antigen-based tests were compared with those obtained by molecular (polymerase chain reaction-based) assays. Results: The antigen-based tests showed sensitivity below 50% and high specificity in all the analyzed age groups. The highest Youden index (J) was observed among adults aged 25-44 years old (45.5, 95% CI 43.7-47.3). Conclusions: We documented the poor performance of serologic techniques as frontline diagnosis of symptomatic COVID-19 and inaccurate results may impact negatively on pandemic progression.

Effectiveness of BNT162b2 COVID-19 Vaccine in Preventing Severe Symptomatic Infection among Healthcare Workers

Background and Objectives: This study aims to evaluate the effectiveness of the BNT162b2 COVID-19 (coronavirus disease 2019) in preventing severe symptomatic laboratory-confirmed infection among healthcare workers in a real-world scenario. Materials and Methods: A cross-sectional analysis of a prospective cohort study was conducted. Subjects with onset illness from January to February 2021 were eligible and classified according to the number of vaccine doses received (single-shot, n = 8; two-shot, n = 12; unvaccinated, n = 290). Results: The vaccine effectiveness against severe illness was 100% in the single and two-shot group. The presented results suggest that vaccination reduces the frequency of severe symptomatic COVID-19 in working-age adults. Conclusions: Efforts focusing on maximizing the number of immunized subjects in the study population may reduce associated economic and social burdens.

COVID-19 mortality among pregnant women in Mexico: A retrospective cohort study

Background

Pregnant women have been classified as at risk for COVID-19 due to previous experience with influenza and other coronaviruses. The objective of this study was to identify risk factors for the complications and death in women of childbearing age and pregnant women with suspected COVID-19.

Methods

This retrospective cohort study was conducted from the beginning of the epidemic in Mexico until May 25, 2020. All women of childbearing age (13-49 years) from the open national COVID-19 database from the Ministry of Health of Mexico were considered for eligibility. SARS-COV-2 infection was confirmed or ruled out by RT-qPCR. We performed a bivariate and multivariable analysis to estimate mortality risk.

Results

Ten (2.2%) pregnant women with confirmed COVID-19 died. Positive pregnant patients did not have a higher risk of complications (admission to the ICU, pneumonia, or requirement for mechanical ventilation) or death than the controls. In the multivariate analysis, only history of diabetes and chronic kidney disease remained independently associated with death in the positive cohort. Seven (0.6%) pregnant women with a negative test died. In bivariate analysis, pregnant patients with a positive test had a higher risk of death than pregnant patients with a negative test (relative risk (RR) = 3.87, 95% confidence interval (CI) = 1.48-10.12), but no higher risk was found than in non-pregnant women with a positive test (RR = 0.82, 95% CI = 0.44-1.53), and 60-day mortality did not significantly differ among pregnant patients with or without a positive test (hazard ratio (HR) = 0.40, 95% CI = 0.12-1.30) or between COVID-19-positive patients who were pregnant or not pregnant (HR = 0.74, 95% CI = 0.35-1.56).

Conclusions

Pregnant patients do not have a greater risk of complications or death from COVID-19 than non-pregnant patients. The presence of diabetes mellitus and chronic disease increases the risk of death in women of childbearing age, but not specifically in pregnant patients.

Male gender and kidney illness are associated with an increased risk of severe laboratory-confirmed coronavirus disease

BACKGROUND

To identify factors predicting severe coronavirus disease 2019 (COVID-19) in adolescent and adult patients with laboratory-positive (quantitative reverse-transcription polymerase chain reaction) infection.

METHOD

A retrospective cohort study took place, and data from 740 subjects, from all 32 states of Mexico, were analyzed. The association between the studied factors and severe (dyspnea requiring hospital admission) COVID-19 was evaluated through risk ratios (RRs) and 95% confidence intervals (CIs).

RESULTS

Severe illness was documented in 28% of participants. In multiple analysis, male gender (RR = 1.13, 95% CI 1.06-1.20), advanced age ([reference: 15-29 years old] 30-44, RR = 1.02, 95% CI 0.94-1.11; 45-59, RR = 1.26, 95% CI 1.15-1.38; 60 years or older, RR = 1.44, 95% CI 1.29-1.60), chronic kidney disease (RR = 1.31, 95% CI 1.04-1.64) and thoracic pain (RR = 1.16, 95% CI 1.10-1.24) were associated with an increased risk of severe disease.

CONCLUSIONS

To the best of our knowledge, this is the first study evaluating predictors of COVID-19 severity in a large subset of the Latin-American population. Male gender and kidney illness were independently associated with the risk of severe COVID-19. These results may be useful for health care protocols for the early detection and management of patients that may benefit from opportune and specialized supportive medical treatment.

Anthropometric and dietary differences among Mexican older adults with and without adequate body image perception

OBJECTIVE

We compared anthropometric and dietary indicators between groups of older Mexican adults with accurate or inaccurate body image perception (BIP).

METHODS

A cross-sectional study was carried out with 201 older adults (age ≥ 60 years) of both sexes who completed the Stunkard scale for BIP, which consists of nine silhouettes with an equivalent of body mass index (BMI) status, then, the accuracy with their real BMI was calculated and reported energy and macronutrient intake through a 24-h dietary recall directed by different geriatric centers in Colima, Mexico. Basic anthropometry and bioelectrical impedance analyses were performed.

RESULTS

We found that 71.1% of the older adults had inaccurate BIP; 66.6% underestimated their body mass and 4.5% overestimated their body mass, the other 28.9% hat accurate BIP. The overall concordance between the real nutritional status and BIP was poor (kappa coefficient = 0.03). The inaccurate BIP group had a significantly higher mean body mass index, body fat percentage, muscle mass, and arm and calf circumference compared to the accurate BIP group (p < .001); only 4.3% of the older adults who were overweight and 6.2% who were obese had an accurate BIP. Regarding dietary consumption, we found significant differences only in energy and carbohydrate intake between the two groups. Finally, excess body fat was associated with an inaccurate BIP (OR: 2.8, 95% CI: 1.5-5.5).

CONCLUSION

In older adults, an inaccurate BIP is generally associated with high anthropometric values and less than adequate dietary intake.

Gestational Diabetes Triggers Oxidative Stress in Hippocampus and Cerebral Cortex and Cognitive Behavior Modifications in Rat Offspring: Age- and Sex-Dependent Effects

Gestational diabetes (GD) has been linked with an increased risk of developing metabolic disorders and behavioral abnormalities in the offspring. Oxidative stress is strongly associated with neurodegeneration and cognitive disruption. In the offspring brains in a GD experimental rat model, increased oxidative stress in the prenatal and postnatal stages was reported. However, long-term alterations to offspring behavior and oxidative stress, caused by changes in the cerebral cortex and hippocampus, remain unclear. In this study, we evaluated the effect of GD on young and adult male and female rat offspring in metabolic parameters, cognitive behavior, and oxidative stress. GD was induced using streptozotocin in dams. Next, the offspring were evaluated at two and six months of age. Anxiety-like behavior was evaluated using the elevated plus maze and open field maze; spatial learning and short-term memory were evaluated using the Morris water maze and radial maze, respectively. We determined oxidative stress biomarkers (reactive oxygen species (ROS), lipid peroxidation and glutathione status) and antioxidant enzymes (superoxide dismutase and catalase) in the brain of offspring. We observed that male GD offspring showed a reduced level of anxiety at both ages as they spent less time in the closed arms of the elevated plus maze at adult age ((P = 0.019, d = 1.083 ( size effect)) and spent more time in the open area of an open field (P = 0.0412, d = 0.743) when young and adult age (P = 0.018, d = 0.65). Adult female GD offspring showed a reduced level of anxiety (P = 0.036; d = 0.966), and young female GD offspring showed a deficiency in spatial learning (P = 0.0291 vs. control, d = 3.207). Adult male GD offspring showed a deficiency in short-term memory (P = 0.017, d = 1.795). We found an increase in ROS and lipid peroxidation, a disruption in the glutathione status, and decreased activity of catalase and superoxide dismutase (P < 0.05 vs. control, d > 1.0), in the cerebral cortex and hippocampus of male and female GD offspring. GD altered metabolism; male offspring of both ages and adult females showed a high level of triglycerides and a lower level of high-density lipoprotein-cholesterol (P < 0.05 vs. control, d > 1.0). Young and adult female offspring displayed higher insulin levels (P < 0.05, d > 1.0). These results suggest that gestational diabetes modifies oxidative stress and cognitive behavior in an age- and sex-dependent manner.

[Obstetric complications of dengue and chikungunya in the pregnant patient: case-control study]

BACKGROUND

Dengue and chikungunya infections are transmitted by the Aedes aegypti vector; they can affect the pregnant woman and her gestation product.

OBJECTIVE

To identify if dengue and chikungunya infections during pregnancy are factors associated with the presence of obstetric complications, in Colima, Mexico.

METHODS

We included in this study 45 patients with obstetric complications and 90 without complications, selected by a two-stage sampling. We collected the sociodemographic, anthropometric, gynecological, and obstetric complications’ data. Descriptive statistics, non-parametric significance tests and crude and adjusted risk estimates (odds ratio [OR] and 95% confidence intervals [95% CI]) were calculated.

RESULTS

Out of 135 patients included, 15 had a diagnosis of dengue and 20 of chikungunya. There were obstetric complications in 60% of infected patients with chikungunya, 46.7% with dengue and 26% of non-infected (p = 0.007). Chikungunya infection (adjusted OR = 1.6) and antecedents of abortion and cesarean section (adjusted OR = 2.2) were independent risk factors associated with the presence of complications. Dengue had an adjusted OR = 1.3 without a statistically significant difference.

CONCLUSIONS

Chikungunya infection and antecedents of abortion and cesarean section are risk factors associated with obstetric complications. Their timely detection is a priority as a preventive strategy.

The Comparative Effect of Nopal and Mucilage in Metabolic Parameters in Rats with a High-Fructose Diet

Nopal is used in Mexico as both food and traditional medicine for metabolic diseases. Our aim was to analyze the effect of the chronic administration of mucilage fiber extracted from nopal (Opuntia ficus indica; 500 mg/kg body weight per day) on male Wistar rats on a high-fructose diet (HFD). After which three groups were administered one of the following for 30 days: whole-fresh nopal mixed in water, mucilage, and control. Metabolic and hemodynamic parameters (triglycerides, cholesterol, fasting glucose, oral glucose tolerance test, blood pressure, and abdominal circumference) were determined. Rats administered nopal and mucilage had lower levels of triglycerides and diastolic arterial pressure than control, but only nopal had significant differences. Furthermore, systolic and diastolic pressure were higher in the control group. Thus, whole nopal and mucilage improve metabolic parameters in rats fed a HFD.

Effects of Moringa oleifera leaf powder on metabolic syndrome induced in male Wistar rats: a preliminary study

Objective To evaluate the preventive effects of Moringa oleifera on metabolic syndrome (MS) in male Wistar rats. Methods MS was induced by feeding rats a high-fat diet and drinking water containing 10% fructose for 6 weeks. In the preventive group, M. oleifera was orally administered for 3 weeks prior to the induction of MS, while in the treatment group, M. oleifera was administered for 3 weeks after the onset of MS. The treatment groups were compared with a control group of untreated rats with induced MS. Fasting glucose, oral glucose tolerance, insulin tolerance, total cholesterol, triglycerides, abdominal circumference, and systolic and diastolic blood pressure were measured before and after MS induction and/or M. oleifera treatment. Results After the induction of MS, the control group had higher fasting glucose levels than the preventive group. No significant differences were observed in insulin tolerance, oral glucose tolerance, cholesterol, triglycerides, abdominal circumference, or systolic or diastolic blood pressure. Compared with untreated controls, rats in the treatment group had significantly improved glucose tolerance, triglycerides, and abdominal circumference. Conclusions M. oleifera treatment attenuates MS in Wistar rats.

[Associated factors with sarcopenia among Mexican elderly: 2012 National Health and Nutrition Survey]

BACKGROUND

Sarcopenia involves the loss of skeletal muscle mass and age-related functionality; it diminishes physical independence, health and quality of life. In 2016 it was added to the International Classification of Diseases (ICD-10). Information about the frequency of sarcopenia among Mexican older adults is scarce. The objective was to analyze associated factors with sarcopenia in Mexican older adults through the 2012 National Health and Nutrition Survey data.

METHODS

Cross-sectional study which included subjects of 60 years of age or more with simultaneous information on health and anthropometry questionnaires from the 2012 National Health and Nutrition Survey. Sarcopenia was diagnosed through a gait speed test and calf circumference. It was assessed the prevalence of sarcopenia and its association with sociodemographic characteristics and variables related to health, tobacco use and alcohol consumption. The analysis was performed with SPSS v. 16.

RESULTS

We analyzed a sample of 5046 older adults who represented 7 439 686 older adults nationwide. Among subjects 53.9% (n = 2718) were women (mean age 69.92 ± 7.56 years) and 46.1% (n = 2328), men (mean age 70.43 ± 7.73 years). Prevalence of presarcopenia was 8.70% and sarcopenia, 13.30%.

CONCLUSION

Sarcopenia was more prevalent in women and it increases with age. It has a significant relationship with falls, cognitive impairment, central obesity and high levels of marginalization.

The Effects of Dietary Iron and Capsaicin on Hemoglobin, Blood Glucose, Insulin Tolerance, Cholesterol, and Triglycerides, in Healthy and Diabetic Wistar Rats

Objective

Our aim was to assess the effects of dietary iron, and the compound capsaicin, on hemoglobin as well as metabolic indicators including blood glucose, cholesterol, triglycerides, insulin, and glucose tolerance.

Materials and Methods

Our animal model was the Wistar rat, fed a chow diet, with or without experimentally induced diabetes. Diabetic males were fed control, low, or high-iron diets, the latter, with or without capsaicin. Healthy rats were fed identical diets, but without the capsaicin supplement. We then measured the parameters listed above, using the Student t-test and ANOVA, to compare groups.

Results

Healthy rats fed a low-iron diet exhibited significantly reduced total cholesterol and triglyceride levels, compared with rats fed a control diet. Significantly reduced blood lipid was also provoked by low dietary iron in diabetic rats, compared with those fed a control diet. Insulin, and glucose tolerance was only improved in healthy rats fed the low-iron diet. Significant increases in total cholesterol were found in diabetic rats fed a high-iron diet, compared with healthy rats fed the same diet, although no statistical differences were found for triglycerides. Hemoglobin levels, which were not statistically different in diabetic versus healthy rats fed the high-iron diet, fell when capsaicin was added. Capsaicin also provoked a fall in the level of cholesterol and triglycerides in diabetic animals, versus diabetics fed with the high iron diet alone. In conclusion, low levels of dietary iron reduced levels of serum triglycerides, hemoglobin, and cholesterol, and significantly improved insulin, and glucose tolerance in healthy rats. In contrast, a high-iron diet increased cholesterol significantly, with no significant changes to triglyceride concentrations. The addition of capsaicin to the high-iron diet (for diabetic rats) further reduced levels of hemoglobin, cholesterol, and triglycerides. These results suggest that capsaicin, may be suitable for the treatment of elevated hemoglobin, in patients.

Models Predictive of Metabolic Syndrome Components in Obese Pediatric Patients

BACKGROUND AND AIMS

Components of metabolic syndrome (MetS) are complications caused by abdominal obesity and insulin resistance (IR). Diagnosis of MetS by clinical indicators could help to identify patients at risk of cardiovascular disease and type 2 diabetes. We undertook this study to propose predictive indicators of MetS in obese children and adolescents.

METHODS

A cross-sectional study was carried out. After obtaining informed consent and the registration of the study with an institutional research committee, 172 obese patients from an Obesity Clinic, aged 6-15 years, were included. Variables included were waist circumference (WC), glucose, high-density lipoprotein (HDL), triglycerides (TGL), blood pressure, insulin resistance (by homeostatic model assessment HOMA-index), acanthosis nigricans (AN), uric acid, serum glutamic oxaloacetic transaminase (GOT) and alanine transaminase, and hepatic sonogram. International standards for age and sex variables were used. Multivariate analysis was applied.

RESULTS

Variables predicted components of MetS in children: HOMA-IR (insulin resistance by HOMA index) was increased by 2.4 in hepatic steatosis, by 0.6 for each unit of SUA (serum uric acid), and by 0.009 for every mg/dL of triglycerides. In adolescents, every cm of waist circumference increased systolic blood pressure by 0.6 mmHg, and each unit of SUA increased it by 2.9 mmHg.

CONCLUSIONS

Serum uric acid and waist circumference are useful and accessible variables that can predict an increased risk of cardiovascular disease in obese pediatric patients.

Presence and colocalization of type-1 cannabinoid receptors with acetylcholine receptors in the motor end-plate of twitch skeletal muscle fibers in the frog

Using polyclonal and monoclonal antibodies to visualize under a confocal microscope type-1 cannabinoid receptors (CB1) and acetylcholine (ACh) receptors, respectively, or α-bungarotoxin conjugated to Alexa-Fluor 555 for Ach receptors, we found that they colocalize on twitch muscle fibers in the frog (Rana pipiens). We show that both the CB1 and ACh receptors are present on the fast skeletal muscle motor end-plate. The CB1 receptor is present along the entire membrane of the muscle fiber, whereas the ACh receptor is expressed primarily at the motor end-plate. Analysis of the colocalization produced a cross-correlation coefficient of 0.519 ± 0.021 (n = 9) for both receptors at the muscle motor end-plate. This study suggests a close proximity between these two types of receptor proteins and that they could interact. CB1 could function at some stage of excitation-contraction coupling in these muscle fibers. However, further investigation is needed in order to clarify these issues.

Cannabinoid receptor type 1 activation by arachidonylcyclopropylamide in rat aortic rings causes vasorelaxation involving calcium-activated potassium channel subunit alpha-1 and calcium channel, voltage-dependent, L type, alpha 1C subunit

Cannabinoids are key regulators of vascular tone, some of the mechanisms involved include the activation of cannabinoid receptor types 1 and 2 (CB); the transient receptor potential cation channel, subfamily V, member 1 (TRPV1); and non-(CB(1))/non-CB2 receptors. Here, we used the potent, selective CB(1) agonist arachidonylcyclopropylamide (ACPA) to elucidate the mechanism underlying vascular tone regulation. Immunohistochemistry and confocal microscopy revealed that CB(1) was expressed in smooth muscle and endothelial cells in rat aorta. We performed isometric tension recordings in aortic rings that had been pre-contracted with phenylephrine. In these conditions, ACPA caused vasorelaxation in an endothelium-independent manner. To confirm that the effect of ACPA was mediated by CB(1) receptor, we repeated the experiment after blocking these receptors with a selective antagonist, AM281. In these conditions, ACPA did not cause vasorelaxation. We explored the role of K(+) channels in the effect of ACPA by applying high-K(+) solution to induce contraction in aortic rings. In these conditions, the ACPA-induced vasorelaxation was about half that observed with phenylephrine-induced contraction. Thus, K(+) channels were involved in the ACPA effect. Furthermore, the vasorelaxation effect was similarly reduced when we specifically blocked calcium-activated potassium channel subunit alpha-1 (KCa1.1) (MaxiK; BKCa) prior to adding ACPA. Finally, ACPA-induced vasorelaxation was also diminished when we specifically blocked the calcium channel, voltage-dependent, L type, alpha 1C subunit (Ca(v)1.2). These results showed that ACPA activation of CB(1) in smooth muscle caused vasorelaxation of aortic rings through a mechanism involving the activation of K(Ca)1.1 and the inhibition of Ca(v)1.2.