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Low glyphosate doses that produce hormesis may alter the susceptibility to herbicides of weeds or enhance their propagation and dispersal. The objective of this work was to evaluate the hormetic effects of glyphosate on the vegetative, phenological and reproductive development in resistant (R) and susceptible (S) Conyza sumatrensis biotypes. The glyphosate resistance level of biotype R was 11.2-fold compared to the S biotype. Glyphosate doses <11.25 g ae ha-1 induced temporary and permanent hormetic effects for the number of leaves, plant height and dry mass accumulation up to 28 d after application in both R and S biotypes. The S biotype required 15-19% fewer thermal units at 1.4 and 2.8 g ae ha-1 glyphosate than untreated plants to reach the bolting stage. Also, this biotype had less thermal units associated with the appearance (1225 vs 1408 units) and opening (1520 vs 1765 units) of the first capitulum than the R biotype. In addition, glyphosate affected reproductive traits of both biotypes compared to their controls, increasing the number of capitulum's and seeds per plant up to 37 and 41% (at 2.8 and 0.7 g ae h-1, respectively) in the S biotype, and by 48 and 114% (both at 5.6 g ae ha-1) in the R biotype. Depending on environmental parameters, glyphosate may or may not cause hormetic effects on the vegetative and phenological development of C. sumatrenis biotypes; however, this herbicide increases the speed and fecundity of reproduction, regardless of the glyphosate susceptibility level, which can alter the population dynamics and glyphosate susceptibility of future generations.

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Glyphosate hormesis, identified as a potential means to enhance crop yields, encounters practical constraints because it is typically assessed through foliar applications. The expression and extend of hormesis in this approach are influenced by unpredictable environmental conditions, highlighting the need to explore alternative glyphosate application methods, such as seed treatment. This study aimed to assess glyphosate hormesis on growth rates and biomass accumulation in seedlings soybean cultivars. Two dose-response experiments [doses from 0 to 2880 g acid equivalent (ae) ha-1], one via foliar and one via seed, were conducted on three soybean cultivars [one non-glyphosate-resistant (NGR) and two glyphosate-resistant (GR, one RR and one RR2)]. In a subsequent experiment, three safe glyphosate doses (0, 90 and 180 g ae ha-1) applied via seed were evaluated on four soybean cultivars (two RR and two RR2). For foliar applications, the range of glyphosate doses increasing growth rates and dry biomass by 12-28 % were 5.6-45 g ae ha-1 for the NGR cultivar, of 45-720 g ae ha-1 for RR and of 11.25-180 g ae ha-1 for RR2. In the seed treatment, biomass increases of 16-60 % occurred at 45-180 g ae ha-1 for the NGR and RR cultivars, and 90-360 g ae ha-1 for RR2. Glyphosate doses of 90 and 180 g ae ha-1, applied via seeds, provided greater growth and biomass accumulation for the RR and RR2 soybean cultivars. Both foliar and seed applications of glyphosate increased growth and biomass accumulation in soybean cultivars, with seed treatments showing greater and more consistent enhancements. These findings propose practical and viable alternative for harnessing glyphosate hormesis to facilitate the early development of soybeans and potentially enhance crop yield.

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Systemic sclerosis (SSc) is an autoimmune disease characterized by systemic inflammation, endothelial dysfunction, generalized fibrosis and high cardiovascular mortality. The evaluation of cardiovascular risk through the visceral adiposity index (VAI) has been helpful due to its direct relationship to the body and visceral fat percentage. We evaluated the influence of body composition and anthropometrics on cardiovascular risk as measured by VAI in healthy controls (HC) and SSc. An analytical cross-sectional study of 66 participants (33 SSc and 33 HC), mean age 52.7 ± 10, 95% women, was conducted from August 2020 to January 2021. Inclusion criteria in cases were consecutive patients with SSc (ACR/EULAR 2013), 63.6% were diffuse cutaneous (dcSS) subtype, and 36.4 were limited cutaneous (lcSS) subtype. HC was matched by age and gender. Serum lipid profiles and InBody anthropometrics were analyzed and compared. We performed descriptive statistics, bivariate analysis with Student's t, or Mann-Whitney U, correlation and chi-square according to the variable type and distribution. Total cholesterol was significantly higher in SSc than HC (345 vs 194, p = < 0.001). The BMI was higher in HC (26.2 vs 28.9, p < 0.001). Kilograms of muscle (19.8 vs 28.9, p < 0.001) and total fat (23.4 vs 28.9, p < 0.001) were lower in SSc patients compared to HC. VAI was similar when BMI < 25, but significantly higher when BMI > 25 in SSc than in HC (3 vs 1.9, p = 0.030). The increase in BMI at overweight or obese in SSc is associated with a significant increase in cardiovascular risk.

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The chorioallantoic membrane (CAM) can be used as a valuable research tool to examine tumors. The CAM can be used to investigate processes such as migration, invasion, and angiogenesis and to assess novel antitumor drugs. The CAM can be used to establish tumors in a straightforward, rapid, and cost-effective manner via xenotransplantation of cells or tumor tissues with reproducible results; furthermore, the use of the CAM adheres to the three "R" principle, i.e., replace, reduce, and refine. To achieve successful tumor establishment and survival, several technical aspects should be taken into consideration. The complexity and heterogeneity of diseases including neuroblastoma and cancers in general and their impact on human health highlight the importance of preclinical models that help us describe tumor-specific biological processes. These models will not only help in understanding tumor biology, but also allow clinicians to explore therapeutic alternatives that will improve current treatment strategies. In this review, we summarize the technical characteristics as well as the main findings regarding the use of this model to study neuroblastoma for angiogenesis, metastasis, drug sensitivity, and drug resistance.

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Resumen El vólvulo de sigmoides ocurre como resultado de una torsión del eje mesentérico colónico, cuenta con una etiología multifactorial y controvertida, de fisiopatología no clara aún. Presenta un cuadro clínico de inicio inespecífico y posteriores signos y síntomas de oclusión intestinal; su diagnóstico se establece mediante tomografía computarizada, con una sensibilidad y especificidad mayor al 90%. El manejo dependerá de la condición clínica del paciente. Caso clínico: Hombre de 29 años con antecedente de síndrome de Asperger. Refirió que desde 7 días previos a su ingreso presentó dolor tipo cólico difuso, asociado a distensión abdominal e intolerancia a la vía oral. Acudió a valoración hospitalaria donde se realizóa tomografía computarizada con niveles hidroaéreos, torsión de arteria mesentérica inferior de aspecto de torbellino. Se realizó laparotomía exploradora a través de la cual se encontró sigmoides dilatado y volvulado, con perforación en la unión rectosigmoidea; se realizó sigmoidectomía con colorectoanastomosis. Al quinto día presentó datos de respuesta inflamatoria con abdomen agudo, por lo que ingresó a laparotomía exploradora donde se encontró dehiscencia de anastomosis; se realizó procedimiento de Hartmann. El paciente presentó choque séptico y falleció a las 24 horas del postquirúrgico. Discusión: La presentación de vólvulo sigmoides generalmente se presenta en personas mayores de 70 años, pocos casos se describen en personas jóvenes y están relacionados con enfermedad de dismotilidad intestinal. El paciente no contaba con factores predisponentes, el diagnóstico se estableció con imágenes características de la enfermedad, como la imagen en torbellino, se decidió manejo quirúrgico con la realización de resección con colorectoanastomosis. Conclusión: La oclusión intestinal por vólvulo sigmoides es una patología infrecuente en jóvenes y de clínica inespecífica. Ante un paciente que presente datos de oclusión intestinal deberá ser abordado de manera apropiada, sobre todo en pacientes en quienes hayan debutado con una clínica insidiosa y persistente de dolor abdominal secundario a oclusión intestinal, sean jóvenes con o sin factores de riesgo.

Abstract Sigmoid volvulus occurs due to a torsion of the colonic mesenteric axis, it has a multifactorial and controversial etiology, and its pathophysiology is not yet clear. Presenting a clinical picture of non-specific onset and later signs and symptoms of intestinal occlusion, its diagnosis is established with computed tomography with a sensitivity and specificity greater than 90%. Management will depend on the clinical condition of the patient. Clinical case: A 29-year-old man with a history of Asperger syndrome. He referred 7 days prior to admission with diffuse cramping pain, associated with abdominal distension and oral intolerance. He went to the hospital for evaluation where a computed tomography was performed with air-fluid levels, torsion of the inferior mesenteric artery with a whirlwind appearance. Exploratory laparotomy was performed, finding a dilated and volvulated sigmoid with perforation at the rectosigmoid junction. A sigmoidectomy with colorectal anastomosis was performed. On the fifth day, he presented data of inflammatory response with acute abdomen, entering exploratory laparotomy finding anastomosis dehiscence, Hartmann procedure was performed. The patient presented septic shock, died 24 hours after surgery. Discussion: The presentation of sigmoid volvulus generally occurs in people older than 70 years, few cases are described in young people and are related to intestinal dysmotility disease, the patient did not have predisposing factors, the diagnosis is established with characteristic images of the disease such as whirlwind image, surgical management is decided by performing resection with colorectal anastomosis. Conclusion: Intestinal occlusion due to sigmoid volvulus is an infrequent pathology in young people and with non-specific symptoms. When faced with a patient presenting evidence of intestinal occlusion, this should be appropriately addressed, especially in patients who have debuted with insidious and persistent symptoms of abdominal pain secondary to intestinal occlusion, whether they are young with or without risk factors.

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The characterization of the mechanisms conferring resistance to herbicides in weeds is essential for developing effective management programs. This study was focused on characterizing the resistance level and the main mechanisms that confer resistance to glyphosate in a resistant (R) Steinchisma laxum population collected in a Colombian rice field in 2020. The R population exhibited 11.2 times higher resistance compared to a susceptible (S) population. Non-target site resistance (NTSR) mechanisms that reduced absorption and impaired translocation and glyphosate metabolism were not involved in the resistance to glyphosate in the R population. Evaluating the target site resistance mechanisms by means of enzymatic activity assays and EPSPS (5-enolpyruvylshikimate-3-phosphate synthase) gene sequencing, the mutation Pro106Ser was found in R plants of S. laxum. These findings are crucial for managing the spread of S. laxum resistance in Colombia. To effectively control S. laxum in the future, it is imperative that farmers use herbicides with different mechanisms of action in addition to glyphosate and adopt Integrate Management Programs to control weeds in rice fields of the central valleys of Colombia.

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Background: The Disability of the Arm, Shoulder and Hand (DASH) questionnaire assesses the impact of upper extremity disorders on quality of life. However, its use in the Mexican population has not been formally validated. Objective: To conduct a cultural adaptation and validation of the DASH questionnaire to evaluate the perspective of patients with neurogenic disorders of the upper extremity regarding the impact on their quality of life. Method: We performed an adaptation of the Spanish version of the DASH questionnaire to the Mexican vocabulary and applied it to 478 volunteers. Ceiling effect, floor effect, item-total correlation, descriptive statistics of items and total score, internal consistency, precision, cross-sectional and longitudinal validity were estimated by comparing healthy controls and affected individuals with different disability levels. Results: Our DASH questionnaire version was equivalent to those previously approved and showed homogeneity of the items with respect to the total value of the questionnaire (Cronbach's alpha > 0.96). In addition, it showed an accuracy of 7.25 points and the crosssectional and longitudinal validity was documented with significant differences between groups and subgroups with distinct disability levels. Conclusions: The DASH questionnaire can be used with a high level of confidence in the Mexican population.

Antecedentes: El cuestionario de discapacidad de brazo, hombro y mano (DASH, Disabilities of the Arm, Shoulder and Hand) mide el impacto de patologías del miembro superior en la calidad de vida. Sin embargo, su uso en la población mexicana no ha sido formalmente validado. Objetivo: Realizar la adaptación cultural y validación del cuestionario DASH para conocer la perspectiva de pacientes con trastornos neurogénicos del miembro superior respecto al impacto en su calidad de vida. Método: Se realizó una adaptación al vocabulario mexicano de la versión española del cuestionario DASH y se aplicó en 478 voluntarios. Se estimaron el efecto techo, el efecto suelo, la correlación ítem-total, las medidas de tendencia central de ítems y el puntaje total, la consistencia interna, la precisión y la validez transversal y longitudinal mediante la comparación de individuos sanos y enfermos con diferente nivel de discapacidad. Resultados: Nuestra versión del cuestionario DASH resultó equivalente a las previamente aprobadas y mostró homogeneidad de los ítems respecto al valor total del cuestionario (alfa de Cronbach > 0.96). Además, tuvo una precisión de 7.25 puntos y se documentó la validez transversal y longitudinal con diferencias significativas entre grupos y subgrupos con diferente nivel de discapacidad. Conclusiones: El cuestionario DASH puede ser empleado con un nivel de confianza alto en la población mexicana.

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Herbicide-resistant weeds have been identified and recorded on every continent where croplands are available. Despite the diversity of weed communities, it is of interest how selection has led to the same consequences in distant regions. Brassica rapa is a widespread naturalized weed that is found throughout temperate North and South America, and it is a frequent weed among winter cereal crops in Argentina and in Mexico. Broadleaf weed control is based on glyphosate that is used prior to sowing and sulfonylureas or mimic auxin herbicides that are used once the weeds have already emerged. This study was aimed at determining whether a convergent phenotypic adaptation to multiple herbicides had occurred in B. rapa populations from Mexico and Argentina by comparing the herbicide sensitivity to inhibitors of the acetolactate synthase (ALS), 5-enolpyruvylshikimate-3-phosphate (EPSPS), and auxin mimics. Five B. rapa populations were analyzed from seeds collected in wheat fields in Argentina (Ar1 and Ar2) and barley fields in Mexico (Mx1, Mx2 and MxS). Mx1, Mx2, and Ar1 populations presented multiple resistance to ALS- and EPSPS-inhibitors and to auxin mimics (2,4-D, MCPA, and fluroxypyr), while the Ar2 population showed resistance only to ALS-inhibitors and glyphosate. Resistance factors ranged from 947 to 4069 for tribenuron-methyl, from 1.5 to 9.4 for 2,4-D, and from 2.7 to 42 for glyphosate. These were consistent with ALS activity, ethylene production, and shikimate accumulation analyses in response to tribenuron-methyl, 2,4-D, and glyphosate, respectively. These results fully support the evolution of the multiple- and cross-herbicide resistance to glyphosate, ALS-inhibitors, and auxinic herbicides in B. rapa populations from Mexico and Argentina.

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Heavy metal pollution is a worldwide environmental and human health problem. Prosopis laevigata is a hyperaccumulator legume that bioaccumulates Pb, Cu and Zn. With interest in designing phytoremediation strategies for sites contaminated with heavy metals, we isolated and characterized endophytic fungi from the roots of P. laevigata growing on mine tailings located in Morelos, Mexico. Ten endophytic isolates were selected by morphological discrimination and a preliminary minimum inhibitory concentration was determined for zinc, lead and copper. A novel strain of Aspergillus closest to Aspergillus luchuensis was determined to be a metallophile and presented a marked tolerance to high concentrations of Cu, Zn and Pb, so it was further investigated for removal of metals and promotion of plant growth under greenhouse conditions. The control substrate with fungi promoted larger size characters in P. laevigata individuals in comparison with the other treatments, demonstrating that A. luchuensis strain C7 is a growth-promoting agent for P. laevigata individuals. The fungus favors the translocation of metals from roots to leaves in P. laevigata, promoting an increased Cu translocation. This new A. luchuensis strain showed endophytic character and plant growth-promotion activity, high metal tolerance, and an ability to increase copper translocation. We propose it as a novel, effective and sustainable bioremediation strategy for copper-polluted soils.

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Hyperglycemia during gestation can disrupt fetal heart development and increase postnatal cardiovascular disease risk. It is therefore imperative to identify early biomarkers of hyperglycemia during gestation-induced fetal heart damage and elucidate the underlying molecular pathomechanisms. Clinical investigations of diabetic adults with heart dysfunction and transgenic mouse studies have revealed that overexpression or increased expression of TNNI3K, a heart-specific kinase that binds troponin cardiac I, may contribute to abnormal cardiac remodeling, ventricular hypertrophy, and heart failure. Optimal heart function also depends on the precise organization of contractile and excitable tissues conferred by intercellular occlusive, adherent, and communicating junctions. The current study evaluated changes in embryonic heart development and the expression levels of sarcomeric proteins (troponin I, desmin, and TNNI3K), junctional proteins, glucose transporter-1, and Ki-67 under fetal hyperglycemia. Stage 22HH Gallus domesticus embryos were randomly divided into two groups: a hyperglycemia (HG) group, in which individual embryos were injected with 30 mmol/L glucose solution every 24 h for 10 days, and a no-treatment (NT) control group, in which individual embryos were injected with physiological saline every 24 h for 10 days (stage 36HH). Embryonic blood glucose, height, and weight, as well as heart size, were measured periodically during treatment, followed by histopathological analysis and estimation of sarcomeric and junctional protein expression by western blotting and immunostaining. Hyperglycemic embryos demonstrated delayed heart maturation, with histopathological analysis revealing reduced left and right ventricular wall thickness (-39% and -35% vs. NT). Immunoexpression levels of TNNI3K and troponin 1 increased (by 37% and 39%, respectively), and desmin immunofluorescence reduced (by 23%). Embryo-fetal hyperglycemia may trigger an increase in the expression levels of TNNI3K and troponin I, as well as dysfunction of occlusive and adherent junctions, ultimately inducing abnormal cardiac remodeling.

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Floating natives (Eichhornia crassipes and Pistia stratiotes) and emergent exotic invasives (Hedychium coronarium and Urochloa arrecta) macrophytes grow as aquatic weeds in both natural and artificial floodplain areas in Brazil, where the chemical control should be researched. The herbicides glyphosate and saflufenacil, alone or mixed, were tested for weed control under simulated floodplain condition in mesocosms. Glyphosate (1,440 g ha-1), saflufenacil (120 g ha-1), or glyphosate (1,440 g ha-1) + saflufenacil (42, 84, and 168 g ha-1) were applied firstly; and 75 days after treatment (DAT), glyphosate (1,680 g ha-1) was applied as a follow-up treatment to control plant regrowth. An herbicide-free check was also used. Echhinornia crassipes was the species most susceptible to the different herbicides. Saflufenacil alone presented the lowest control on the macrophytes (≤45%) from 7 to 75 DAT, and in most cases they presented high regrowth rates, i.e., this herbicide was the least effective treatment in reducing the dry mass production of the macrophyte community. Glyphosate alone presented low efficacy to control H. coronarium (30-65%), but for the other macrophytes, it presented control peaks ≥90%, maintaining control levels ≥50% until 75 DAT. Glyphosate + saflufenacil, regardless rate of saflufenacil, caused similar damage to glyphosate in E. crassipes and P. stratiotes; however, in U. arrecta it caused 20-30% less injury. In contrast, these treatments provided the best control of H. coronarium. The complementary application of glyphosate was essential to improve the level of control of the first application, after plant regrowth.

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Despite the extensive information available on the different genetic, epigenetic, and molecular features of cardiogenesis, the origin of congenital heart defects remains unknown. Most genetic and molecular studies have been conducted outside the context of the progressive anatomical and histological changes in the embryonic heart, which is one of the reasons for the limited knowledge of the origins of congenital heart diseases. We integrated the findings of descriptive studies on human embryos and experimental studies on chick, rat, and mouse embryos. This research is based on the new dynamic concept of heart development and the existence of two heart fields. The first field corresponds to the straight heart tube, into which splanchnic mesodermal cells from the second heart field are gradually recruited. The overall aim was to create a new vision for the analysis, diagnosis, and regionalized classification of congenital defects of the heart and great arteries. In addition to highlighting the importance of genetic factors in the development of congenital heart disease, this study provides new insights into the composition of the straight heart tube, the processes of twisting and folding, and the fate of the conus in the development of the right ventricle and its outflow tract. The new vision, based on in vivo labeling and cell tracking and enhanced by models such as gastruloids and organoids, has contributed to a better understanding of important errors in cardiac morphogenesis, which may lead to several congenital heart diseases.

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A series of novel 1-N-α-d-glucopyranosyl-1H-1,2,3-triazole xanthines was synthesized from azido sugars (glucose, galactose, and lactose) and propargyl xanthines (theophylline and theobromine) using a typical copper (I)-catalyzed azide-alkyne 1,3-dipolar cycloaddition. The corrosion inhibition activities of these new carbohydrate-xanthine compounds were evaluated by studying the corrosion of API 5 L X70 steel in a 1 M HCl medium. The results showed that, at 10 ppm, a 90% inhibition efficiency was reached by electrochemical impedance spectroscopy. The inhibitory efficiency of these molecules is explained by means of quantum chemical calculations of the protonated species with the solvent effect, which seems to better represent the actual situation of the experimental conditions. Some quantum chemical parameters were analyzed to characterize the inhibition performance of the tested molecules.

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In the present study, the nematicidal and acaricidal activity of three Enterobacter endophytic strains isolated from Mimosa pudica nodules was evaluated. The percentages of mortality of Enterobacter NOD4 against Panagrellus redivivus was 81.2%, and against Nacobbus aberrans 70.1%, Enterobacter NOD8 72.4% and 62.5%, and Enterobacter NOD10 64.8% and 58.7%, respectively. While against the Tyrophagus putrescentiae mite, the mortality percentages were 68.2% due to Enterobacter NOD4, 64.3% due to Enterobacter NOD8 and 77.8% due to Enterobacter NOD10. On the other hand, the ability of the three Enterobacter strains to produce indole acetic acid and phosphate solubilization, characteristics related to plant growth-promoting bacteria, was detected. Bioinformatic analysis of the genomes showed the presence of genes related to IAA production, phosphate solubilization, and nitrogen fixation. Phylogenetic analyzes of the recA gene, phylogenomics, and average nucleotide identity (ANI) allowed us to identify the strain Enterobacter NOD8 related to E. mori and Enterobacter NOD10 as E. asburiae, while Enterobacter NOD4 was identified as a possible new species of this species. The plant growth-promoting, acaricidal and nematicidal activity of the three Enterobacter strains makes them a potential agent to include in biocontrol alternatives and as growth-promoting bacteria in crops of agricultural interest.

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Fortunately, we live in the era of evidence-based medicine. The progress that we had in the treatment of cancer and the decrease of futile and unnecessary procedures previously performed is undeniable. Nowadays, although, it seems that we are tending to the other extreme: trying to justify not performing procedures or invasive treatments in the name of the 'Death with Dignity'.

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Manuscript symbols can be stored, recognized and retrieved from an entropic digital memory that is associative and distributed but yet declarative; memory retrieval is a constructive operation, memory cues to objects not contained in the memory are rejected directly without search, and memory operations can be performed through parallel computations. Manuscript symbols, both letters and numerals, are represented in Associative Memory Registers that have an associated entropy. The memory recognition operation obeys an entropy trade-off between precision and recall, and the entropy level impacts on the quality of the objects recovered through the memory retrieval operation. The present proposal is contrasted in several dimensions with neural networks models of associative memory. We discuss the operational characteristics of the entropic associative memory for retrieving objects with both complete and incomplete information, such as severe occlusions. The experiments reported in this paper add evidence on the potential of this framework for developing practical applications and computational models of natural memory.

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OBJECTIVE: Several controversies remain on conservative management of cervical cancer. Our aim was to develop a consensus recommendation on important and novel topics of fertility-sparing treatment of cervical cancer. METHODS: The consensus was sponsored by the Brazilian Society of Surgical Oncology (BSSO) from March 2020 to September 2020 and included a multidisciplinary team of 55 specialists. A total of 21 questions were addressed and they were assigned to specialists' groups that reviewed the literature and drafted preliminary recommendations. Further, the coordinators evaluated the recommendations that were classified by the level of evidence, and finally, they were voted by all participants. RESULTS: The questions included controversial topics on tumor assessment, surgical treatment, and surveillance in conservative management of cervical cancer. The two topics with lower agreement rates were the role of minimally invasive approach in radical trachelectomy and parametrial preservation. Additionally, only three recommendations had <90% of agreement (fertility preservation in Stage Ib2, anti-stenosis device, and uterine transposition). CONCLUSIONS: As very few clinical trials have been developed in surgery for cervical cancer, most recommendations were supported by low levels of evidence. We addressed important and novel topics in conservative management of cervical cancer and our study may contribute to literature.

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A study of 250 commercial drugs to act as corrosion inhibitors on steel has been developed by applying the quantitative structure-activity relationship (QSAR) paradigm. Hard-soft acid-base (HSAB) descriptors were used to establish a mathematical model to predict the corrosion inhibition efficiency (IE%) of several commercial drugs on steel surfaces. These descriptors were calculated through third-order density-functional tight binding (DFTB) methods. The mathematical modeling was carried out through autoregressive with exogenous inputs (ARX) framework and tested by fivefold cross-validation. Another set of drugs was used as an external validation, obtaining SD, RMSE, and MSE, obtaining 6.76%, 3.89%, 7.03%, and 49.47%, respectively. With a predicted value of IE% = 87.51%, lidocaine was selected to perform a final comparison with experimental results. By the first time, this drug obtained a maximum IE%, determined experimentally by electrochemical impedance spectroscopy measurements at 100 ppm concentration, of about 92.5%, which stands within limits of 1 SD from the predicted ARX model value. From the qualitative perspective, several potential trends have emerged from the estimated values. Among them, macrolides, alkaloids from Rauwolfia species, cephalosporin, and rifamycin antibiotics are expected to exhibit high IE% on steel surfaces. Additionally, IE% increases as the energy of HOMO decreases. The highest efficiency is obtained in case of the molecules with the highest ω and ΔN values. The most efficient drugs are found with pKa ranging from 1.70 to 9.46. The drugs recurrently exhibit aromatic rings, carbonyl, and hydroxyl groups with the highest IE% values.

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Atta and Acromyrmex are the main genera of leaf-cutting ants present in North and South America, causing extensive damage to agroforestry. Control of the ants requires high handling costs with few effective methods available to decrease the losses. The symbiosis between the leaf-cutting ants and the fungus Leucoagaricus gongylophorus is essential for ant nest survival. Therefore, L. gongylophorus may be a key target in controlling leaf-cutting ants, since its reduction may cause an imbalance in the symbiosis necessary to maintain the nest. Among the options for natural fungal control, plant species are considered important sources of compounds belonging to several classes of natural products that show potential as antifungal agents. This review also presents studies that establish that the antagonist fungi from the Escovopsis and Trichoderma genera effectively reduce the development of L. gongylophorus. The development of nanostructured delivery systems, which have shown advantages over conventional formulations, is suggested for ant control; no commercial nanotechnology-based product has yet been developed, and this appears to be a new approach for future studies.

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The corrosion inhibition of 5-O-ß-D-glucopyranosyl-7-methoxy-3',4'-dihydroxy-4-phenylcoumarin (4-PC) in AISI 1018 steel immersed in 3% NaCl + CO2 was studied by electrochemical impedance spectroscopy (EIS). The results showed that, at just 10 ppm, 4-PC exerted protection against corrosion with Õ² = 90% and 97% at 100 rpm. At static conditions, the polarization curves indicated that, at 5 ppm, the inhibitor presented anodic behavior, while at 10 and 50 ppm, there was a cathodic-type inhibitor. The inhibitor adsorption was demonstrated to be chemisorption, according to the Langmuir isotherm for 100 and 500 rpm. By means of SEM-EDS, the corrosion inhibition was demonstrated, as well as the fact that the organic compound was effective for up to 72 h of immersion. At static conditions, dispersion-corrected density functional theory results reveal that the chemical bonds established by the phenyl group of 4-PC are responsible of the chemisorption on the steel surface. According with Fukui reactivity indices, the molecules adsorbed on the metal surface provide a protective cover against nucleophilic and electrophilic attacks, pointing to the corrosion inhibition properties of 4-PC.

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