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Phytopathogenic fungi Alternaria alternata and Colletotrichum gloeosporioides cause diseases in plant tissues as well as significant postharvest losses. The use of chemical fungicides for their control has negative effects on health and the environment. Secondary metabolites from halophilic bacteria are a promising alternative for new antifungal compounds. In the present study, halophilic bacteria were isolated and characterized from two sites with saline soils called branquizales in Campeche, Mexico. A total of 64 bacteria were isolated. Agrobacterium, Bacillus, Inquilinus, Gracilibacillus, Metabacillus, Neobacillus, Paenibacillus, Priestia, Staphylococcus, Streptomyces and Virgibacillus were among the identified genera. The antifungal potential of the culture supernatant (CS) of 39 halophilic bacteria was investigated against C. gloeosporioides and A. alternata. The bacteria showing the greatest inhibition of mycelial growth corresponded to Bacillus subtilis CPO 4292, Metabacillus sp. CPO 4266, Bacillus sp. CPO 4295 and Bacillus sp. CPO 4279. The CS of Bacillus sp. CPO 4279 exhibited the highest activity and its ethyl acetate extract (AcOEt) inhibited the germination of C. gloeosporioides, with IC50 values of 8,630µg/ml and IC90 of 10,720µg/ml. The organic partition of the AcOEt extract led to three fractions, with acetonitrile (FAcB9) showing the highest antifungal activity, with values exceeding 66%. Halophilic bacteria from 'blanquizales' soils of the genus Bacillus sp. produce metabolites with antifungal properties that inhibit the phytopathogenic fungus C. gloeosporioides.

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BACKGROUND: The awake prone positioning strategy for patients with acute respiratory distress syndrome is a safe, simple and cost-effective technique used to improve hypoxaemia. We aimed to evaluate intubation and mortality risk in patients with coronavirus disease 2019 (COVID-19) who underwent awake prone positioning during hospitalisation. METHODS: In this retrospective, multicentre observational study conducted between 1 May 2020 and 12 June 2020 in 27 hospitals in Mexico and Ecuador, nonintubated patients with COVID-19 managed with awake prone or awake supine positioning were included to evaluate intubation and mortality risk through logistic regression models; multivariable and centre adjustment, propensity score analyses, and E-values were calculated to limit confounding. RESULTS: 827 nonintubated patients with COVID-19 in the awake prone (n=505) and awake supine (n=322) groups were included for analysis. Fewer patients in the awake prone group required endotracheal intubation (23.6% versus 40.4%) or died (19.8% versus 37.3%). Awake prone positioning was a protective factor for intubation even after multivariable adjustment (OR 0.35, 95% CI 0.24-0.52; p<0.0001, E=2.12), which prevailed after propensity score analysis (OR 0.41, 95% CI 0.27-0.62; p<0.0001, E=1.86) and mortality (adjusted OR 0.38, 95% CI 0.26-0.55; p<0.0001, E=2.03). The main variables associated with intubation among awake prone patients were increasing age, lower baseline peripheral arterial oxygen saturation/inspiratory oxygen fraction ratio (P aO2 /F IO2 ) and management with a nonrebreather mask. CONCLUSIONS: Awake prone positioning in hospitalised nonintubated patients with COVID-19 is associated with a lower risk of intubation and mortality.

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Resumen: El uso de la pausa al final de la inspiración (PFI) en ventilación mecánica data de hace más de 50 años y con mayor impulso en la década de los 70, se le atribuye una mejoría en la presión parcial de oxígeno arterial (PaO2) al incrementar la presión media de la vía aérea (Pma), mayor aclaramiento de la presión parcial de dióxido de carbono arterial (PaCO2) y permite la monitorización de la presión meseta (Pmeseta) en la mecánica ventilatoria; sin embargo, los estudios clínicos sobre su uso son escasos y controversiales. En este artículo se abordan los mecanismos fisiológicos, fisiopatológicos y la evidencia sobre el uso de la PFI en ventilación mecánica (VM).

Abstract: The use of the end inspiratory pause (EIP) in mechanical ventilation has been going on for more than 50 years and with greater momentum in the 1970s, an improvement in the partial pressure of arterial oxygen (PaO2) is attributed to the increase mean airway pressure, greater clearance of partial pressure of arterial carbon dioxide and allows monitoring of plateau pressure in ventilatory mechanics; However, the Clinical studies on its use are few and controversial. This article addresses the physiological and pathophysiological mechanisms and the evidence on the use of EIP in mechanical ventilation.

Resumo: A utilização da pausa ao final da inspiração (PFI) na ventilação mecânica remonta a mais de 50 anos e com maior impulso na década de 70, atribui-se uma melhora na pressão parcial de oxigênio arterial (PaO2) pelo aumento da pressão média das vias aéreas (Pma), uma maior depuração da pressão parcial de dióxido de carbono arterial (PaCO2) e permite a monitorização da pressão de platô (Pplateau) na mecânica ventilatória, porém estudos Os dados clínicos sobre seu uso são escassos e controversos. Este artigo aborda os mecanismos fisiológicos e fisiopatológicos e as evidências sobre o uso do PFI na ventilação mecânica (VM).

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The scrotal nerves in the rat were studied electrophysiologically to describe their topographic organization in the skin and in the dorsal roots, and to determine if the electrical properties of these afferents are under the influence of testosterone. There are 2 afferent nerve branches innervating this area, the proximal scrotal branch supplying the proximal half of the scrotum (PSb), and the distal scrotal branch supplying the distal half (DSb). Results showed that afferent axons from PSb enter the spinal cord through the L5 and L6 dorsal roots, and axons from DSb enter the cord through the L6 and S1 dorsal roots. Mechanical stimulation of the scrotal skin exposed 3 dermatome areas, the L5, L6, and S1, with L6 being the longest dermatome with intermingled terminals from PSb and DSb. Decreased levels of testosterone after castration increased the threshold to trigger the activity of scrotal afferents, and the exogenous administration of the hormone reverted it. This effect was similar in the dorsal penile nerve. The decrease in androgen levels produced a reduction in the skin sensory field to mechanical stimuli that was restored after the administration of the hormone. As the scrotal nerves are highly stimulated during copulation in parallel with the dorsal penile nerve, it is suggested that the sensory field of the scrotal skin could be closely related to the modifications in sexual behavior after testosterone manipulation.

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