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En Ecuador, en el cultivo de Banano (Musa spp.), la principal enfermedad es la Sigatoka negra, causada por el hongo Mycosphaerella fijiensis Morelet, se caracteriza por tener reproducción sexual y asexual (Paracercospora fijiensis), ocasionando una alta diseminación de esporas dentro de las plantaciones bananeras. La investigación tuvo como objetivo evaluar alternativas de fungicidas protectantes azufrados y microbiológicos, dentro de las combinaciones de fungicidas, como estrategias de control de la Sigatoka negra. Se utilizó un Diseño de bloques Completamente al Azar, conformado por 7 tratamientos y 10 repeticiones, el análisis estadístico se realizó mediante el análisis de varianza ANOVA y los promedios fueron comparados mediante la prueba de Tukey. Las variables evaluadas fueron porcentaje de área foliar afectada y el área bajo la curva del progreso de la enfermedad (ABCPE) durante toda la epidemia, evidenciándose el tratamiento T7 como la mejor estrategia de control frente a la enfermedad. Los resultados sugieren que el azufre elemental 800 gr/Kg a una dosis 3Kg/ha, puede integrarse en las combinaciones de fungicidas, como estrategia de control de la sigatoka negra, obteniendo buenos niveles de control.

This article analyses the history of the Cuban economy over a very long period. Its first part (last edition) was devoted to the period extending from 1492, when the island was “discovered”, to 1898, when the War of Independence ended. This part analyses the development of the economcy during the 20th century until the victory of the Revolution in 1959.

The p53 tumor suppressor is an indispensable regulator of DNA damage responses that accelerates carcinogenesis when mutated. In this report, we uncover a new mechanism by which p53 maintains genomic integrity in the absence of canonical DNA damage response activation. Specifically, loss of p53 dramatically alters chromatin structure at the nuclear periphery, allowing increased transmission of an environmental carcinogen, ultraviolet (UV) radiation, into the nucleus. Genome-wide mapping of UV-induced DNA lesions in p53-deficient primary cells reveals elevated lesion abundance in regions corresponding to locations of high mutation burden in malignant melanomas. These findings uncover a novel role of p53 in the suppression of mutations that contribute to cancer and highlight the critical influence of nuclear architecture in regulating sensitivity to carcinogens., Competing Interests: Competing interests: Authors declare that they have no competing interests.

Environmental pollution caused by petroleum-derived plastics continues to increase annually. Consequently, current research is interested in the search for eco-friendly bacterial polymers. The importance of Bacillus bacteria as producers of polyhydroxyalkanoates (PHAs) has been recognized because of their physiological and genetic qualities. In this study, twenty strains of Bacillus genus PHA producers were isolated. Production was initially evaluated qualitatively to screen the strains, and subsequently, the strain B12 or Bacillus sp. 12GS, with the highest production, was selected through liquid fermentation. Biochemical and molecular identification revealed it as a novel isolate of Bacillus cereus . Production optimization was carried out using the Taguchi methodology, determining the optimal parameters as 30 °C, pH 8, 150 rpm, and 4% inoculum, resulting in 87% and 1.91 g/L of polyhydroxybutyrate (PHB). Kinetic studies demonstrated a higher production within 48 h. The produced biopolymer was analyzed using Fourier-transform infrared spectroscopy (FTIR), confirming the production of short-chain-length (scl) polyhydroxyalkanoate, named PHB, and differential scanning calorimetry (DSC) analysis revealed thermal properties, making it a promising material for various applications. The novel B. cereus isolate exhibited a high %PHB, emphasizing the importance of bioprospecting, study, and characterization for strains with biotechnological potential.

The study's objective was to develop and validate the psychometric properties of two brief pictorial scales to evaluate the roles of bystanders and victims of bullying. A sample of 910 students was considered (49.6%, boys; 50.4%, girls) between the ages of 7 and 13 (M = 10, SD = 1.4). Both instruments present nine pictorial items representing two dimensions: physical bullying (items 1 to 4) and psychological bullying (items 5 to 9). An additional measure of anxiety was used to assess convergent validity. The Confirmatory Factorial Analysis shows that the two-dimensional oblique model, physical bullying and psychological bullying, presents a better fit to the bystander scale data (RMSEA = .040; CFI = .984; SRMR = .033) and in the victim scale (RMSEA = .051; CFI = .978; SRMR = .040) in comparison to other competitor models. From the perspective of the Item Response Theory (IRT), it was found that the items adequately discriminate the levels of the latent variable; therefore, items 1 (physical bullying) and 7 (psychological bullying) are the most accurate on the bystander scale, and items 3 (physical bullying) and 7 (psychological bullying), on the victim scale. It was also found that the degree of difficulty on both scales is lower for the psychological bullying dimension than for the physical bullying dimension. Both instruments demonstrated good psychometric properties; therefore, they can detect school bullying in classrooms.

The aortic valve facilitates unidirectional blood flow to the systemic circulation between the left cardiac ventricle and the aorta. The valve's biomechanical function relies on thin leaflets to adequately open and close over the cardiac cycle. A monolayer of valve endothelial cells (VECs) resides on the outer surface of the aortic valve leaflet. Deeper within the leaflet are sublayers of valve interstitial cells (VICs). Valve tissue remodeling involves paracrine signaling between VECs and VICs. Aortic valve calcification can result from abnormal paracrine communication between these two cell types. VECs are known to respond to hemodynamic stimuli, and, specifically, flow abnormalities can induce VEC dysfunction. This dysfunction can subsequently change the phenotype of VICs, leading to aortic valve calcification. However, the relation between VEC-exposed flow oscillations under pulsatile flow to the progression of aortic valve calcification by VICs remains unknown. In this study, we quantified the level of flow oscillations that VECs were exposed to under dynamic culture and then immersed VICs in VEC-conditioned media. We found that VIC-induced calcification was augmented under maximum flow oscillations, wherein the flow was fully forward for half the cardiac cycle period and fully reversed for the other half. We were able to computationally correlate this finding to specific regions of the aortic valve that experience relatively high flow oscillations and that have been shown to be associated with severe calcified deposits. These findings establish a basis for future investigations on engineering calcified human valve tissues and its potential for therapeutic discovery of aortic valve calcification.

Polyhydroxyalkanoates (PHA) are microbially produced biopolymers which are biodegradable and biocompatible. These compounds produced by microorganisms have been described as a potent alternative to synthetic plastics, which are often recalcitrant. Here, we report the draft genome sequence of a PHA-producing Bacillus cereus isolated in our laboratory.

Carcinogenic insult, such as UV light exposure, creates DNA lesions that evolve into mutations if left unrepaired. These resulting mutations can contribute to carcinogenesis and drive malignant phenotypes. Susceptibility to carcinogens (i.e., the propensity to form a carcinogen-induced DNA lesion) is regulated by both genetic and epigenetic factors. Importantly, carcinogen susceptibility is a critical contributor to cancer mutagenesis. It is known that mutations can be prevented by tumor suppressor regulation of DNA damage response pathways; however, their roles carcinogen susceptibility have not yet been reported. In this study, we reveal that the retinoblastoma (RB1) tumor suppressor regulates UV susceptibility across broad regions of the genome. In particular, centromere and telomere-proximal regions exhibit significant increases in UV lesion susceptibility when RB1 is deleted. Several cancer-related genes are located within genomic regions of increased susceptibility, including telomerase reverse transcriptase, TERT , thereby accelerating mutagenic potential in cancers with RB1 pathway alterations. These findings reveal novel genome stability mechanisms of a tumor suppressor and uncover new pathways to accumulate mutations during cancer evolution., (© 2022 Wong et al.)

Exposure to the ultraviolet (UV) radiation in sunlight creates DNA lesions, which if left unrepaired can induce mutations and contribute to skin cancer. The two most common UV-induced DNA lesions are the cis-syn cyclobutane pyrimidine dimers (CPDs) and pyrimidine (6-4) pyrimidone photoproducts (6-4PPs), both of which can initiate mutations. Interestingly, mutation frequency across the genomes of many cancers is heterogenous with significant increases in heterochromatin. Corresponding increases in UV lesion susceptibility and decreases in repair are observed in heterochromatin versus euchromatin. However, the individual contributions of CPDs and 6-4PPs to mutagenesis have not been systematically examined in specific genomic and epigenomic contexts. In this study, we compared genome-wide maps of 6-4PP and CPD lesion abundances in primary cells and conducted comprehensive analyses to determine the genetic and epigenetic features associated with susceptibility. Overall, we found a high degree of similarity between 6-4PP and CPD formation, with an enrichment of both in heterochromatin regions. However, when examining the relative levels of the two UV lesions, we found that bivalent and Polycomb-repressed chromatin states were uniquely more susceptible to 6-4PPs. Interestingly, when comparing UV susceptibility and repair with melanoma mutation frequency in these regions, disparate patterns were observed in that susceptibility was not always inversely associated with repair and mutation frequency. Functional enrichment analysis hint at mechanisms of negative selection for these regions that are essential for cell viability, immune function and induce cell death when mutated. Ultimately, these results reveal both the similarities and differences between UV-induced lesions that contribute to melanoma., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Lignocellulosic wastes may provide a means to economize polyhydroxybutyrate (PHB) production. This study has proposed the use of Agave durangensis leaves obtained from the artisanal mezcal industry as a novel substrate for this aim. Results revealed an increase in PHB biosynthesis (0.32 g/L) and improvement in %PHB (16.79-19.51%) by Bacillus cereus 4N when A. durangensis leaves used as carbon source were physically pre-treated by ultrasound for 30 min (ADL + US30') and thermally pre-treated (ADL + Q). Chemical analyses and SEM studies revealed compositional and morphological changes when A. durangensis leaves were physically pre-treated. Also, elemental analysis of growth media showed that carbon/nitrogen ratios of 14-21, and low nitrogen, hydrogen, and protein content were well-suited for PHB biosynthesis. Confocal microscopy revealed morphological changes in the bacterial cell and carbonosome structure under the influence of different substrates. Finally, Fourier transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC) analyses showed that homopolymeric PHB with a high thermal-resistance (271.94-272.89 °C) was produced. Therefore, the present study demonstrates the potential use of physically pre-treated A. durangensis leaves to produce PHB. These results promote the development of a circular economy in Mexico, where lignocellulosic wastes can be employed to produce value-added biotechnological products., Competing Interests: Declaration of competing interest None., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Nowadays, there are great research interest in polyhydroxybutyrate (PHB) recovery protocols that reduce the use of organic solvents and efficiently recover this bacterial biopolymer. The present study reports an extraction protocol assisted by ultrasound, which is a rapid protocol that increases the amount of polymeric matter extracted, reduces the cellular digestion step with sodium hypochlorite and eliminates the use of organic solvents. Likewise, characterization studies by Fourier transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance spectroscopy ( 1 H NMR), differential scanning calorimetry (DSC), and X-ray diffraction (XRD) demonstrated that the biopolymer recovered by this protocol is PHB homopolymer with a major thermal-resistance and crystalline properties. Besides, in this study are reported the thermic and crystalline differences between the PHB obtained from the fermentation of complex carbohydrates (agavins) and simple sugars. The biopolymer obtained by this rapid extraction protocol would be suitable for ecological and biomedical applications, due to the low melting temperature, less than 50% crystallinity, and the lack of lipopolysaccharides. Therefore, this extraction protocol might represent an alternative to the traditional protocol based on NaOCl-chloroform and is part of the green trend to improve the PHB production., Competing Interests: Declaration of competing interest None., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Somatic mutations in driver genes may ultimately lead to the development of cancer. Understanding how somatic mutations accumulate in cancer genomes and the underlying factors that generate somatic mutations is therefore crucial for developing novel therapeutic strategies. To understand the interplay between spatial genome organization and specific mutational processes, we studied 3,000 tumor-normal-pair whole-genome datasets from 42 different human cancer types. Our analyses reveal that the change in somatic mutational load in cancer genomes is co-localized with topologically-associating-domain boundaries. Domain boundaries constitute a better proxy to track mutational load change than replication timing measurements. We show that different mutational processes lead to distinct somatic mutation distributions where certain processes generate mutations in active domains, and others generate mutations in inactive domains. Overall, the interplay between three-dimensional genome organization and active mutational processes has a substantial influence on the large-scale mutation-rate variations observed in human cancers.

Introduction: To recognise the relationship between the needle tip and the median nerve during peripheral nerve block is of interest to avoid neural damage. However, signs of intraneural injection are not clearly established. The aim of this study was to define the changes observed in the peripheral nerve after the intraneural or perineural administration of 1ml of solution., Material and Methods: Ultrasound guided median nerve blocks were performed in the forearm of 10 fresh cadavers on 60 occasions (3 per forearm). They were randomised into the intraneural (n=30) or perineural (n=30) location of the needle tip, after the consensus of location by 7 specialists. After 1ml of solution was injected an evaluation was made of the changes in the cross-sectional area of the nerve, as well as the displacement along the nerve., Results: The cross-sectional area of the median nerve was increased in both groups, however, the increase was significantly higher in the intraneural group (perineural 0.007±0.013cm2 vs. intraneural 0.032±0.021cm2, P<.0001). An increase of more than 27% of the area ensures an intraneural injection in the median nerve according to the ROC curve analysis. Both proximal and distal diffusion were observed more frequently in the intraneural group (proximal: 86% vs 14%, P<.0001, Distal: 43% vs 4%, P<.0001)., Conclusions: Based on this experimental study, it is concluded that the injection of a small volume (1ml) allows to discriminate the disposition of the intraneural vs perineural needle in a high percentage of cases. Therefore, it is suggested that this "dose test" should be considered in the safety algorithms if it is required to reduce the incidence of intraneural injection., (Copyright © 2018 Sociedad Española de Anestesiología, Reanimación y Terapéutica del Dolor. Publicado por Elsevier España, S.L.U. All rights reserved.)

The development of many sporadic cancers is directly initiated by carcinogen exposure. Carcinogens induce malignancies by creating DNA lesions (i.e., adducts) that can result in mutations if left unrepaired. Despite this knowledge, there has been remarkably little investigation into the regulation of susceptibility to acquire DNA lesions. In this study, we present the first quantitative human genome-wide map of DNA lesions induced by ultraviolet (UV) radiation, the ubiquitous carcinogen in sunlight that causes skin cancer. Remarkably, the pattern of carcinogen susceptibility across the genome of primary cells significantly reflects mutation frequency in malignant melanoma. Surprisingly, DNase-accessible euchromatin is protected from UV, while lamina-associated heterochromatin at the nuclear periphery is vulnerable. Many cancer driver genes have an intrinsic increase in carcinogen susceptibility, including the BRAF oncogene that has the highest mutation frequency in melanoma. These findings provide a genome-wide snapshot of DNA injuries at the earliest stage of carcinogenesis. Furthermore, they identify carcinogen susceptibility as an origin of genome instability that is regulated by nuclear architecture and mirrors mutagenesis in cancer., (© 2017 The Authors.)

Objective: This study was conducted to determine whether β-blocker (BB) therapy is associated with abdominal aortic aneurysm (AAA) sac regression after endovascular abdominal aortic repair (EVAR)., Methods: A total of 198 patients (mean age, 76 years) who underwent EVAR were analyzed (104 in the BB group and 94 in the non-BB group). The primary end point was the incidence of AAA sac regression at 1 and 2 years., Results: Hypertension, coronary artery disease, and hyperlipidemia were more common in the BB group. The BB group was also more likely to have been prescribed an aspirin and a statin than the non-BB group. The length of proximal neck was significantly longer in the non-BB group than in the BB group. All study patients were monitored for at least 1 year after EVAR, and 2-year follow-up was available in 104 patients (52.5%). There was no statistically significant difference in the incidence of aneurysm sac regression in either group at 1 year (52.1% in the non-BB group vs 45.2% in the BB group; P = .330) and 2 years (58.5% in the non-BB group vs 64.7% in the BB group; P = .515). The difference of the change of AAA maximum diameter between two groups did not reach statistical significance at 1 year (-6.0 ± 7.0 mm in the non-BB group vs -5.5 ± 8.1 mm in the BB group; P = .644) and 2 years (-9.0 ± 10.5 mm in the non-BB group vs -9.0 ± 10.0 mm in the BB group; P = .977). BB therapy was not associated with increased odds of AAA sac regression. The effect of third-generation BBs on AAA sac regression was not significant., Conclusions: BB therapy had no effect on AAA sac regression. At the present time, there is insufficient evidence to recommend BB therapy for the purpose of AAA sac regression., (Copyright © 2016 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.)

Purpose: To determine whether statin therapy is associated with abdominal aortic aneurysm (AAA) sac regression after endovascular aneurysm repair (EVAR)., Materials and Methods: A total of 109 patients treated with EVAR were retrospectively analyzed (no-statin group, n = 45; statin group, n = 64). The primary endpoint was the incidence of AAA sac regression. To investigate independent predictors of AAA sac regression, regression analysis was performed. The mean age was 74 years (range, 55-90 y), and 87.2% of patients were men., Results: The no-statin group had higher rates of AAA sac regression than the statin group at 1 year (no-statin group, 66.7%; statin group, 45.3%; P = .028). The incidence of AAA sac regression increased over time in the statin group, and no statistical difference was seen between the two groups at 2 years (no-statin group, 66.7%; statin group, 57.8%; P = .350). The difference between the changes in maximum AAA diameter was significant between groups at 1 year (no-statin group vs statin group, -4.9 mm ± 5.9; P = .041), but the difference did not reach statistical significance at 2 years (no-statin group, -10.0 mm ± 10.1; statin group, -8.0 mm ± 9.6; P = .306). Statin therapy was not associated with AAA sac regression on univariate (odds ratio [OR], 0.685; 95% confidence interval [CI], 0.310-1.516; P = .351) and multivariate analyses (OR, 0.617; 95% CI, 0.215-1.772; P = .369)., Conclusions: Statin therapy had no effect on AAA sac regression at 2 years. There is insufficient evidence to recommend statin therapy for AAA sac regression., (Copyright © 2016 SIR. Published by Elsevier Inc. All rights reserved.)

Objective: We investigated whether successful revascularization of total occlusion of a large lower-extremity artery is associated with improvement of left ventricular (LV) diastolic function., Background: Total occlusion of a large lower-extremity artery might affect the systemic vascular resistance and increase the afterload, because the left ventricle must work harder to eject blood into a smaller vascular bed. Chronic elevation of afterload is a cause of LV diastolic dysfunction., Methods: This is a single-center retrospective analysis of 20 patients (10 men, age 69.6 ± 12.3 years) with chronic total occlusions (CTOs) of the aorto-iliac and femoropopliteal segments who underwent a successful endovascular revascularization. Baseline and postprocedural evaluation of diastolic function was performed, and the primary endpoint was improvement in LV diastolic function, which was defined as any decrease of the baseline E/E' ratio or any increase of the baseline E' velocity after the index procedure., Results: There was a significant effect of successful revascularization on the E/A ratio (from 1.5 ± 1.1 to 1.0 ± 0.3; P=.046) because of a significant increase of A velocity (from 86.3 ± 30.4 cm/s to 98.3 ± 21.8 cm/s; P=.03). The E' velocity (from 7.4 ± 2.0 cm/s to 8.3 ± 2.3 cm/s; P=.07) did not show a significant increase, but there was a significant reduction in E/E' ratio (from 14.6 ± 3.9 to 12.4 ± 3.3; P=.02). Logistic regression analysis did not identify possible predictors of improvement in LV diastolic function., Conclusion: Our results showed that a successful revascularization was associated with improvement in the echocardiographic parameters of LV diastolic function in patients with CTO of large lower-extremity artery, and these changes may be related to the afterload reduction.

Purpose: To determine whether statin therapy is associated with reduced restenosis following nitinol stent implantation for de novo femoropopliteal artery disease., Materials and Methods: A total of 135 limbs in 135 patients (mean age, 72 y) implanted with nitinol stents in femoropopliteal occlusions were analyzed (statin arm, n = 91; nonstatin arm, n = 44). The patients were treated with one type of nitinol stent., Results: At baseline, lesions and procedural characteristics were comparable between groups, except that the statin group had more hypertension, coronary artery disease, and hyperlipidemia. There were significant differences in the incidence of binary restenosis between groups at 1 year (45.5% for nonstatin group vs 28.6% for statin group; P = .05) and 2 years (56.8% for nonstatin group vs 38.5% for statin group; P = .04). Primary patency rates at 1 year were 50.5% in the nonstatin group and 72.5% in the statin group (P = .01). Two-year target lesion revascularization rates were 54.5% in the nonstatin group and 35.2% in the statin group (P = .03). On univariate analysis, statin therapy was associated with decreased relative risk of binary restenosis at 1 year (odds ratio [OR], 0.480; 95% confidence interval [CI], 0.227-1.014; P = .050). On multivariate analysis, statin therapy did not significantly affect the odds of binary restenosis (OR, 0.415; 95% CI, 0.071-2.437; P = .330)., Conclusions: The incidence of binary restenosis was significantly lower in the statin group than in the nonstatin group following nitinol stent implantation for de novo femoropopliteal artery disease., (Copyright © 2016 SIR. Published by Elsevier Inc. All rights reserved.)