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Tomato is one of the most important fruits worldwide. It is widely consumed due to its sensory and nutritional attributes. However, like many other industrial crops, it is affected by biotic and abiotic stress factors, reducing its metabolic and physiological processes. Tomato plants possess different mechanisms of stress responses in which hormones have a pivotal role. They are responsible for a complex signaling network, where the antioxidant system (enzymatic and non-enzymatic antioxidants) is crucial for avoiding the excessive damage caused by stress factors. In this sense, it seems that hormones such as ethylene, auxins, brassinosteroids, and salicylic, jasmonic, abscisic, and gibberellic acids, play important roles in increasing antioxidant system and reducing oxidative damage caused by different stressors. Although several studies have been conducted on the stress factors, hormones, and primary metabolites of tomato plants, the effect of endogenous and/or exogenous hormones on the secondary metabolism is still poorly studied, which is paramount for tomato growing management and secondary metabolites production. Thus, this review offers an updated overview of both endogenous biosynthesis and exogenous hormone application in the antioxidant system of tomato plants as a response to biotic and abiotic stress factors. [ABSTRACT FROM AUTHOR]

Conflicting results have been obtained through meta-analyses for the role of obesity as a risk factor for adverse outcomes in patients with coronavirus disease-2019 (COVID-19), possibly due to the inclusion of predominantly multimorbid patients with severe COVID-19. Here, we aimed to study obesity alone or in combination with other comorbidities as a risk factor for short-term all-cause mortality and other adverse outcomes in Mexican patients evaluated for suspected COVID-19 in ambulatory units and hospitals in Mexico. We performed a retrospective observational analysis in a national cohort of 71 103 patients from all 32 states of Mexico from the National COVID-19 Epidemiological Surveillance Study. Two statistical models were applied through Cox regression to create survival models and logistic regression models to determine risk of death, hospitalisation, invasive mechanical ventilation, pneumonia and admission to an intensive care unit, conferred by obesity and other comorbidities (diabetes mellitus (DM), chronic obstructive pulmonary disease, asthma, immunosuppression, hypertension, cardiovascular disease and chronic kidney disease). Models were adjusted for other risk factors. From 24 February to 26 April 2020, 71 103 patients were evaluated for suspected COVID-19; 15 529 (21.8%) had a positive test for SARS-CoV-2; 46 960 (66.1%), negative and 8614 (12.1%), pending results. Obesity alone increased adjusted mortality risk in positive patients (hazard ratio (HR) = 2.7, 95% confidence interval (CI) 2.04–2.98), but not in negative and pending-result patients. Obesity combined with other comorbidities further increased risk of death (DM: HR = 2.79, 95% CI 2.04–3.80; immunosuppression: HR = 5.06, 95% CI 2.26–11.41; hypertension: HR = 2.30, 95% CI 1.77–3.01) and other adverse outcomes. In conclusion, obesity is a strong risk factor for short-term mortality and critical illness in Mexican patients with COVID-19; risk increases when obesity is present with other comorbidities. [ABSTRACT FROM AUTHOR]

Most of the existing prediction models for COVID-19 lack validation, are inadequately reported or are at high risk of bias, a reason which has led to discourage their use. Few existing models have the potential to be extensively used by healthcare providers in low-resource settings since many require laboratory and imaging predictors. Therefore, we sought to develop and validate a multivariable prediction model of death in Mexican patients with COVID-19, by using demographic and patient history predictors. We conducted a national retrospective cohort study in two different sets of patients from the Mexican COVID-19 Epidemiologic Surveillance Study. Patients with a positive reverse transcription-polymerase chain reaction for SARS-CoV-2 and complete unduplicated data were eligible. In total, 83 779 patients were included to develop the scoring system through a multivariable Cox regression model; 100 000, to validate the model. Eight predictors (age, sex, diabetes, chronic obstructive pulmonary disease, immunosuppression, hypertension, obesity and chronic kidney disease) were included in the scoring system called PH-Covid19 (range of values: −2 to 25 points). The predictive model has a discrimination of death of 0.8 (95% confidence interval (CI) 0.796–0.804). The PH-Covid19 scoring system was developed and validated in Mexican patients to aid clinicians to stratify patients with COVID-19 at risk of fatal outcomes, allowing for better and efficient use of resources. [ABSTRACT FROM AUTHOR]

Edible films can incorporate antimicrobial extracts to provide microbiological stability on food surfaces. The aim of this study was to evaluate chitosan or starch edible films added by selected concentrations of Mexican oregano (Lippia berlandieri Schauer) essential oil to control anthracnose. Chitosan and starch edible films were formulated with essential oil concentrations of 0.00, 0.25, 0.50, 0.75, 1.00, 2.00, or 4.00%. Mold radial growth was evaluated by modified Gompertz equation. A significant (p < 0.05) change of Gompertz parameters was observed among essential oil concentrations, increasing the lag phase and decreasing radial growth rates as oil concentration increased. [ABSTRACT FROM AUTHOR]