Paralog editing tunes rice stomatal density to maintain photosynthesis and improve drought tolerance.

Rice (Oryza sativa) is of paramount importance for global nutrition, supplying at least 20% of global calories. However, water scarcity and increased drought severity are anticipated to reduce rice yields globally. We explored stomatal developmental genetics as a mechanism for improving drought resilience in rice while maintaining yield under climate stress. CRISPR/Cas9-mediated knockouts of the positive regulator of stomatal development STOMAGEN and its paralog EPIDERMAL PATTERNING FACTOR-LIKE10 (EPFL10) yielded lines with ∼25% and 80% of wild-type stomatal density, respectively. epfl10 lines with moderate reductions in stomatal density were able to conserve water to similar extents as stomagen lines but did not suffer from the concomitant reductions in stomatal conductance, carbon assimilation, or thermoregulation observed in stomagen knockouts. Moderate reductions in stomatal density achieved by editing EPFL10 present a climate-adaptive approach for safeguarding yield in rice. Editing the paralog of STOMAGEN in other species may provide a means for tuning stomatal density in agriculturally important crops beyond rice.

The Radioprotective Potentials of Silymarin/Silibinin Against Radiotherapy- Induced Toxicities: A Systematic Review of Clinical and Experimental Studies.

BACKGROUND: Although radiotherapy is one of the main cancer treatment modalities, exposing healthy organs/tissues to ionizing radiation during treatment can lead to different adverse effects. In this regard, it has been shown that the use of radioprotective agents may alleviate the ionizing radiation-induced toxicities. OBJECTIVE: The present study aims to review the radioprotective potentials of silymarin/silibinin in the prevention/reduction of ionizing radiation-induced adverse effects on healthy cells/tissues. METHODS: Based on PRISMA guidelines, a comprehensive and systematic search was performed for identifying relevant literature on the "potential protective role of silymarin/silibinin in the treatment of radiotherapy-induced toxicities" in the different electronic databases of Web of Science, PubMed, and Scopus up to April 2022. Four hundred and fifty-five articles were obtained and screened in accordance with the inclusion and exclusion criteria of the current study. Finally, 19 papers were included in this systematic review. RESULTS: The findings revealed that the ionizing radiation-treated groups had reduced survival rates and body weight in comparison with the control groups. It was also found that radiation can induce mild to severe adverse effects on the skin, digestive, hematologic, lymphatic, respiratory, reproductive, and urinary systems. Nevertheless, the administration of silymarin/silibinin could mitigate the ionizing radiation-induced adverse effects in most cases. This herbal agent exerts its radioprotective effects through anti-oxidant, anti-apoptosis, anti-inflammatory activities, and other mechanisms. CONCLUSION: The results of the current systematic review showed that co-treatment of silymarin/silibinin with radiotherapy alleviates the radiotherapy-induced adverse effects in healthy cells/tissues.

Stable nitrogen and oxygen isotope fractionation during precipitation of nitrate salt from saturated solutions.

RATIONALE: Nitrate is an oxyanion similar to CO3 - and thus should undergo stable N and O isotope fractionation during dissolution or precipitation. This process should dominate abiotic soil nitrate processes in hyperarid regions of Earth and possibly Mars. METHODS: The N and O isotope fractionations during the precipitation of nitrate salt from saturated solutions at ~20°C were determined by two methods: rapid precipitation by antisolvent crystallization and slow uninhibited precipitation in a desiccator. In the antisolvent crystallization procedure, increasing volumes of acetone were added to samples of saturated sodium and strontium nitrate solutions to instantaneously precipitate nitrate salt. In the slow procedure (requiring weeks), slow evaporative water loss drove the process. RESULTS: There was little difference between the two procedures. Using a Rayleigh model, the calculated N fractionation (15 εproduct-residual ) ranged from 1.69‰ to 2.77‰, whereas for O, the 18 εproduct-residual values were between 1.27‰ and 4.61‰. The N isotope fractionation between NO3 - and the metal solid is similar to that between C in dissolved CO3 -2 and carbonates. We found that O versus N isotope plots of soil nitrate in a cold/dry Antarctic chronosequence had slopes similar to those from the experiments, revealing abiotic transport. In the Atacama Desert, where the soil nitrates are a mix of biological and tropospheric nitrate, there is an inverse relationship between soil N and O isotopes. These two relationships were compared with the isotope composition of nitrate from Martian meteorite EETA79001. CONCLUSIONS: While the N and O isotope composition of the Martian nitrate is remarkably similar to that of the present Atacama Desert, the interpretation of the slope of the O versus N isotopes remains ambiguous due to the limited number of samples. Additional NO3 samples from Martian meteorites are needed to address the question of abiotic versus biotic alteration of NO3 - on Mars.

Seeding the Self-Assembly of DNA Origamis at Surfaces.

Unlike supramolecular self-assembly methods that can organize many distinct components into designer shapes in a homogeneous solution (e.g., DNA origami), only relatively simple, symmetric structures consisting of a few distinct components have been self-assembled at solid surfaces. As the self-assembly process is confined to the surface/interface by mostly nonspecific attractive interactions, an open question is how these interfacial interactions affect multicomponent self-assembly. To gain a mechanistic understanding of the roles of the surface environment in DNA origami self-assembly, here we studied the oligonucleotide-assisted folding of a long single-stranded DNA (ssDNA scaffold) that was end-tethered to a dynamic surface, which could actively regulate the DNA-surface interactions. The results showed that even weak surface attractions can lead to defective structures by inhibiting the merging of multiple domains into complete structures. A combination of surface anchoring and deliberate regulation of DNA-surface interactions allowed us to depart from the existing paradigm of surface confinement via nonspecific interactions and enabled DNA origami folding to proceed in a solution-like environment. Importantly, our strategy retains the key advantages of surface-mediated self-assembly. For example, surface-anchored oligonucleotides could sequence-specifically initiate the growth of DNA origamis of specific sizes and shapes. Our work enables information to be encoded into a surface and expressed into complex DNA surface architectures for potential nanoelectronic and nanophotonic applications. In addition, our approach to surface confinement may facilitate the 2D self-assembly of other molecular components, such as proteins, as maintaining conformational freedom may be a general challenge in the self-assembly of complex structures at surfaces.

Clinical implications of convergent procoagulant toxicity and differential antivenom efficacy in Australian elapid snake venoms.

Australian elapid snakes are some of the most venomous snakes in the world and are unique among venomous snakes in having mutated forms of the blood clotting factor X in an activated form (FXa) as a key venom component. In human bite victims, an overdose of this activated clotting enzyme results in the systemic consumption of fibrinogen due to the large amounts of endogenous thrombin generated by the conversion of prothrombin to thrombin by venom FXa. Within Australian elapids, such procoagulant venom is currently known from the tiger snake clade (Hoplocephalus, Notechis, Paroplocephalus, and Tropidechis species), brown/taipan (Oxyuranus and Pseudonaja species) clade, and the red-bellied black snake Pseudechis porphyriacus. We used a STA-R Max coagulation analyser and TEG5000 thromboelastographers to test 47 Australian elapid venoms from 19 genera against human plasma in vitro. In addition to activity being confirmed in the two clades above, FXa-driven potent procoagulant activity was found in four additional genera (Cryptophis, Demansia, Hemiaspis, and Suta). Ontogenetic changes in procoagulant function was also identified as a feature of Suta punctata venom. Phylogenetic analysis of FX sequences confirmed that snake venom FXa toxins evolved only once, that the potency of these toxins against human plasma has increased in a stepwise fashion, and that multiple convergent amplifications of procoagulant activity within Australian elapid snakes have occurred. Cofactor dependence tests revealed all procoagulant venoms in our study, except those of the tiger snake clade, to be highly calcium-dependent, whereas phospholipid dependence was less of a feature but still displayed significant variation between venoms. Antivenom testing using CSL Tiger Snake Antivenom showed broad but differential cross-reactivity against procoagulant venoms, with P. porphyriacus and S. punctata extremely well neutralised but with Cryptophis, Demansia, and Hemiaspis less well-neutralised. The relative variation was not in accordance to genetic relatedness of the species used in antivenom production (Notechis scutatus), which underscores a fundamental principle that the rapid evolution characteristic of venoms results in organismal phylogeny being a poor predictor of antivenom efficacy. Our results have direct and immediate implications for the design of clinical management plans in the event of snakebite by such lesser known Australian elapid snake species that have been revealed in this study to be as potent as the better studied, and proven lethal, species.

Ablación de fibrilación auricular, ictus y hemorragia digestiva: desenlace fatal / Atrial fibrillation ablation, stroke, and hematemesis: fatal outcome

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Differential procoagulant effects of saw-scaled viper (Serpentes: Viperidae: Echis) snake venoms on human plasma and the narrow taxonomic ranges of antivenom efficacies.

Saw-scaled vipers (genus Echis) are one of the leading causes of snakebite morbidity and mortality in parts of Sub-Saharan Africa, the Middle East, and vast regions of Asia, constituting a public health burden exceeding that of almost any other snake genus globally. Venom-induced consumption coagulopathy, owing to the action of potent procoagulant toxins, is one of the most relevant clinical manifestations of envenomings by Echis spp. Clinical experience and prior studies examining a limited range of venoms and restricted antivenoms have demonstrated for some antivenoms an extreme lack of antivenom cross-reactivity between different species of this genus, sometimes resulting in catastrophic treatment failure. This study undertook the most comprehensive testing of Echis venom effects upon the coagulation of human plasma, and also the broadest examination of antivenom potency and cross-reactivity, to-date. 10 Echis species/populations and four antivenoms (two African, two Asian) were studied. The results indicate that the venoms are, in general, potently procoagulant but that the relative dependence on calcium or phospholipid cofactors is highly variable. Additionally, three out of the four antivenoms tested demonstrated only a very narrow taxonomic range of effectiveness in preventing coagulopathy, with only the SAIMR antivenom displaying significant levels of cross-reactivity. These results were in conflict with previous studies using prolonged preincubation of antivenom with venom to suggest effective cross-reactivity levels for the ICP Echi-Tab antivenom. These findings both inform upon potential clinical effects of envenomation in humans and highlight the extreme limitations of available treatment. It is hoped that this will spur efforts into the development of antivenoms with more comprehensive coverage for bites not only from wild snakes but also from specimens widely kept in zoological collections.

Cambios de comportamiento, uso y beneficios de un programa comunitario para la promoción de la actividad física / Behavioral changes, used and benefits of a community program for the promotion in physical activity / Mudanças de comportamento, uso e benefícios de um programa comunitário para a promoção da atividade física

Objetivo: Determinar el cambio de comportamiento frente a la actividad física y las características relacionadas con el uso y los beneficios del Centro Local de Actividad Física (CLAF), en la población de la localidad de Santa Fe de la ciudad de Bogotá. Materiales y métodos: Se realizó un estudio longitudinal de antes y después, donde se evaluó, al ingreso y a los tres meses de estar en el programa de intervención en actividad física del CLAF, el cambio de comportamiento frente a la actividad física de los usuarios. Los criterios de inclusión fueron: ser usuario activo del CLAF, tener edad de entre 15 y 65 años y manifestar voluntariamente su participación en el estudio. El criterio de exclusión era: diligenciamiento incompleto de los instrumentos de medición utilizados. Del marco muestral del usuarios del CLAF, se seleccionaron n= 55 sujetos que cumplieron los criterios de selección. Para la recolección de la información se diseñó un cuestionario que contenía los estadios de cambio de comportamiento frente a la actividad física; también se realizó una encuesta semiestructurada donde se determinaron características acerca de los beneficios y uso del CLAF. Resultados: El total de los participantes del estudio fue n= 55, el promedio de edad fue 40.4 ± 15.3 años, con una mínima de 15 y una máxima de 64 años; el 83.6% fueron mujeres. El 78.2% desconoce el propósito del Centro Local de Actividad Física. La estrategia de divulgación que más llegó al grupo fue la de tipo verbal con un 58.2%. El tiempo de vinculación al CLAF de más frecuencia en el grupo evaluado fue de 1 a 6 meses, con un 36.4%. La motivación para asistir regularmente al CLAF, en la mayoría, fue la de mejorar la salud física y/o mental, con un 74.5%. El 89.1% estaría dispuesto a recomendar a otras personas el uso del CLAF. Un 81.8% de la población realizaba actividad física por más de 150 min/semana a intensidad moderada. Post intervención del CLAF, en los sujetos del estudio se evidenciaron cambios significativos en el nivel de actividad física (p<0.001, Test de Wilcoxon) y en el estado de comportamiento (p<0.001, Test de Wilcoxon).

Objective: To determine the change of behavior in physical activity and the characteristics associated with the use and benefits of Local Physical Activity Center (CLAF) in the population of the town of Santa Fe de Bogota. Materials and methods: We conducted a longitudinal study before and after, which was assessed at admission and 3 months in the intervention program CLAF physical activity, behavior change compared to the physical activity of users. Inclusion criteria: were being active user of CLAF, aged between 15 and 65 years and voluntarily express their participation in the study. Exclusion criteria: Fill incomplete measurement instruments used. The sampling frame of CLAF users, we selected n=55 subjects. To gather information, a questionnaire, which contained the behavioral stages of change, also conducted a survey which determined semistructured features about the benefits and use of CLAF. Results: The total study participants was n = 55, mean age was 40.4 ± 15.3 years, with a minimum 15 and maximum of 64 years, 83.6% were women. 78.2% do not know the purpose of the Local Centre for Physical Activity. The outreach strategy that most came to the group was 58.2 with a verbal type. The time for links to CLAF more frequently in the group evaluated was 1 to 6 months 36.4. The motivation to regularly attend the CLAF in the majority was to improve the physical and / or a 74.5% mental. 89.1% would be willing to recommend to others the use of CLAF. A 81.8% of the population physical activity performed by more than 150 min / wk at moderate intensity; Post CLAF intervention in the subjects showed positive changes in the level of physical activity (p<0.001, Test de Wilcoxon) and behavioral state (p<0.001, Test de Wilcoxon).

Objetivo: Determinar a mudança de comportamento frente á atividade física e as características relacionadas com o uso e os benefícios do Centro Local de Atividade Física (CLAF), na população da localidade de Santa Fe da cidade de Bogotá. Materiais e métodos: Realizou-se um estudo longitudinal de antes e depois, onde se avaliou, ao ingresso e aos três meses de estar no programa de intervenção em atividade física do CLAF, a mudança de comportamento a atividade física dos usuários. Os critérios de inclusão foram: ser usuário ativo do CLAF, ter idade entre 15 e 65 anos, e manifestar voluntariamente sua participação no estudo. O critério de exclusão era: preenchimento incompleto dos instrumentos de medição utilizados. Da base de amostragem dos usuários do CLAF, se selecionaram n= 55 sujeitos que cumpriram os critérios de seleção. Para a colheita da informação desenho-se um questionário que continha os estádios de mudança de comportamento frente á atividade física; também se realizou uma enquete semi-estruturada onde se determinaram características com respeito aos benefícios e uso do CLAF. Resultados: O total dos participantes do estudo foi n= 55, a média de idade foi 40.4 ± 15.3 anos, com uma mínima de 15 e uma máxima de 64 anos; o 83,6% foram mulheres. O 78,2% desconhece o propósito do Centro Local de Atividade Física. A estratégia de divulgação que funcionou com o grupo foi a de tipo verbal com um 58,2%. O tempo de vinculação ao CLAF de maior freqüência no grupo avaliado foi de 1 a 6 meses, com um 36,4%. A motivação para assistir regularmente ao CLAF, na maioria, foi a de melhorar a saúde física e/ou mental, com um 74,5%. O 89,1% estaria disposto a recomendar a outras pessoas o uso do CLAF. Um 81,8% da população realizava atividade física por mais de 150 min./semana a intensidade moderada. Pós-ão do CLAF, nos sujeitos de estudo se evidenciaram mudanças significativas no nível de atividade física (p<0.001, Test de Wilcoxon) e no estado de comportamento (p<0.001, Test de Wilcoxon).

Cambios en el LAG de acomodación al emplear estímulos visuales de diferentes tamaños / Changes in LAG of accommodation by using different sizes visual stimulus

La medición de la respuesta acomodativa (LAG de acomodación) tiene gran importancia clínica, puesto que ayuda en el diagnóstico de las disfunciones del sistema de vergencias y acomodativas. Sin embargo,en la forma como es evaluado clínicamente no se ha estandarizado cuál debe ser el tamaño del objeto que se observa. Objetivo: determinar los cambios en el LAG de acomodación con estímulos de diferentes tamaños. Metodología: se realizó un estudio cuasiexperimental con 134 personas (269 ojos), seleccionadas según el cumplimiento de criterios de inclusión y exclusión, que fueron expuestas a diferentes tamaños de estímulos acomodativos para determinar cambios en la respuesta acomodativa con la retinoscopía de Nott. Resultados: no se encontró variación significativa cuando el estímulo fueron letras o dibujo(límites de acuerdo ±0,14 D). Cuando la luz se utilizó como estimulo, generó una variación clínica y estadísticamente significativa (límites de acuerdo 95% 0,03 - 0,34). Conclusiones: se debe evaluar el LAG de acomodación o realizar una retinoscopía dinámica (Merchán, 1966), con puntos de fijación,como letras o figuras acordes a la edad y nivel de atención del sujeto.

The assess LAG of accommodation has clinical significance,since they help in the diagnosis of system failures and accommodative vergence. However there is no standardized clinical evaluation which should be the size of the object being observed. Objective:to Determine changes in the LAG of accommodation with stimuli of different sizes. Methods: We performed a quasi-experimental study, where exposure was developed at different sizes of stimulus and accommodative response was measured on a group of patients, 134 individuals (269 eyes), selected according to the following inclusion and exclusion criteria. Results: It wasn´t found a significant variation, when the stimulus is figure or drawing (limits of agreement ± 0.14 D), whereas when light was usedas stimulus produces statistically and clinically significant change (limits of agreement 0.03 to 0.34).Conclusions: Should be evaluated LAG accommodation or make a dynamic retinoscopy (Merchán), with attachment points as letters or figures appropriate age and level of attention from the subject.