Long-Lasting Silver Nanoparticles Synthesized with Tagetes erecta and Their Antibacterial Activity against Erwinia amylovora, a Serious Rosaceous Pathogen.

A rapid, eco-friendly, and simple method for the synthesis of long-lasting (2 years) silver nanoparticles (AgNPs) is reported using aqueous leaf and petal extracts of Tagetes erecta L. The particles were characterized using UV-Visible spectrophotometry and the analytical and crystallographic techniques of transmission electron microscopy (TEM). The longevity of the AgNPs was studied using UV-Vis and high-resolution TEM. The antibacterial activity of the particles against Erwinia amylovora was evaluated using the Kirby-Bauer disk diffusion method. The results were analyzed using ANOVA and Tukey's test (p ≤ 0.05). Both the leaf and petal extracts produced AgNPs, but the leaf extract (1 mL) was long-lasting and quasi-spherical (17.64 ± 8.87 nm), with an absorbance of UV-Vis λmax 433 and a crystalline structure (fcc, 111). Phenols, flavonoids, tannins, and terpenoids which are associated with -OH, C=O, and C=C were identified in the extracts and could act as reducing and stabilizing agents. The best antibacterial activity was obtained with a nanoparticle concentration of 50 mg AgNPs L-1. The main contribution of the present research is to present a sustainable method for producing nanoparticles which are stable for 2 years and with antibacterial activity against E. amylovora, one of most threatening pathogens to pear and apple productions.

The Cancer-Protective Potential of Protocatechuic Acid: A Narrative Review.

Cancer is one of the leading causes of death worldwide, making the search for alternatives for its control a critical issue. In this context, exploring alternatives from natural sources, such as certain vegetables containing a variety of secondary metabolites with beneficial effects on the body and that play a crucial role in the fight against cancer, is essential. Among the compounds with the greatest efficacy in controlling this disease, those with antioxidant activity, particularly phenolic com-pounds, stand out. A remarkable example of this group is protocatechuic acid (PCA), which has been the subject of various revealing research on its activities in different areas. These studies sustain that protocatechuic acid has anti-inflammatory, antimutagenic, antidiabetic, antiulcer, antiviral, antifibrogenic, antiallergic, neuroprotective, antibacterial, anticancer, antiosteoporotic, anti-aging, and analgesic properties, in addition to offering protection against metabolic syndrome and con-tributing to the preservation of hepatic, renal, and reproductive functionality. Therefore, this paper aims to review the biological activities of PCA, focusing on its anticancer potential and its in-volvement in the control of various molecular pathways involved in tumor development, sup-porting its option as a promising alternative for cancer treatment.

Perceived instructor presence, interactive tools, student engagement, and satisfaction in hybrid education post-COVID-19 lockdown in Mexico.

Interactive communication platforms have been widely used to support online teaching. However, during the Coronavirus Diseases 2019 (COVID-19) pandemic they gained unprecedented relevance since they allowed educational processes to continue. This study investigated the relationship among interactive communication technology tools, perceived instructor presence, student satisfaction and engagement in hybrid courses post-COVID-19 lockdown. An electronic questionnaire was administered to 1086 students from a public university in Mexico that implemented a hybrid class model using Microsoft Teams after the lockdown. Jamovi and WarpPLS were used to perform confirmatory factor analysis and structural equation modeling. The findings revealed that interactive technological communication tools positively impact the instructor's perceived presence, student satisfaction and engagement. Similarly, commitment significantly positively impacted student satisfaction. The model demonstrated a good fit. The findings were consistent with studies before and during the lockdown. The instructor's perceived presence promotes student engagement and satisfaction, and Microsoft Teams effectively facilitates this presence. These findings suggest that interactive communication tools are and will be significant in educational contexts and modalities. This study provides useful insights for educators, course designers and educational administrators, emphasizing effective communication with students and implementing interactive technological communication tools to enhance hybrid learning in the post-pandemic era.

Actividad y discapacidad en pacientes cubanos con artritis reumatoide como factores que influyen en la sexualidad

Introducción: La artritis reumatoide es una enfermedad autoinmune de carácter inflamatorio y crónico. La afectación en la esfera sexual es frecuente, compromete a ambos sexos y se relaciona con factores como el dolor, la discapacidad y el consumo de medicamentos. Esta afectación no ha sido suficientemente abordada en la literatura a pesar de su prevalencia, y en Cuba no se han reportado hasta el momento estudios relacionados sobre este tema de investigación. Objetivo: Determinar el impacto de la artritis reumatoide en la sexualidad y su relación en la actividad y la discapacidad. Métodos: Se realizó un estudio monocéntrico, transversal, descriptivo. Se incluyeron los pacientes con un diagnóstico de artritis reumatoide en el período comprendido de septiembre de 2019 a junio de 2021. Se utilizó el cuestionario Qualisex para evaluar el impacto de la artritis reumatoide en la sexualidad. Resultados: En el estudio doscientos veintiséis pacientes fueron incluidos, la media de edad fue de 53,38 años (DE ± 12,22) el 82,7 % fueron mujeres. Al responder el autocuestionario Qualisex el 73,9 % de los sujetos presentaron afectación en la sexualidad. No se estableció una relación significativa entre la afectación en la esfera sexual y el tiempo de evolución. A diferencia de los niveles altos de actividad y discapacidad. Conclusiones: En la población estudiada se presentó afectación en la sexualidad, no obstante, esta no se relacionó con el tiempo de evolución de la artritis reumatoide. Se encontró asociación entre la actividad de la enfermedad y la capacidad funcional con la afectación en la esfera sexual.

Introduction: Rheumatoid arthritis is a chronic, inflammatory autoimmune disease. Disorders in the sexual sphere is frequent, it affects both sexes and it is related to factors such as pain, disability and medication consumption. This condition has not been sufficiently addressed in the literature despite its prevalence and in Cuba no studies related to the topic under study have been reported to date. Objective: To determine the impact of rheumatoid arthritis on sexuality and its relationship with activity and disability. Methods: A monocentric, cross-sectional and descriptive study was carried out on patients with a diagnosis of rheumatoid arthritis, from September 2019 to June 2021. The Qualisex questionnaire was used to evaluate the impact of rheumatoid arthritis on sexuality. Results: Two hundred twenty-six patients were included, the mean age was 53.38 years (SD ± 12.22) and 82.7% were women. When answering the Qualisex self-questionnaire, 73.9% of the subjects had effects in their sexuality. No significant relationship was established between the involvement in the sexual sphere and the time of evolution. Conclusions: The impact on sexuality in the studied population was not related to the duration of rheumatoid arthritis. On the other hand, an association was found between disease activity and functional capacity with effects in the sexual sphere.

Current perspectives for external control arms in oncology clinical trials: Analysis of EMA approvals 2016-2021.

Leveraging external control data, especially real-world data (RWD), has drawn particular attention in recent years for facilitating oncology clinical development and regulatory decision-making. Medical regulators have published guidance on accelerating the use of RWD and external controls. However, few systematic discussions have been conducted on external controls in cancer drug submissions and regulatory feedback. This study aimed to identify European oncology drug approvals using external control data to demonstrate clinical efficacy. We included 18 eligible submissions employing 24 external controls and then discussed the use of external control, data sources, analysis methods, and regulators' feedback. The external controls have been actively submitted to the European Medical Agency (EMA) recently. We found that 17 % of the EMA-approved cancer drugs in 2016-2021 used external controls, among which 37 % of the cases leveraged RWD. However, nearly one-third of the external controls were not considered supportive evidence by EMA due to limitations regarding heterogeneous patient populations, missing outcome assessment in RWD, and inappropriate statistical analysis. This study highlighted that proper use of external controls requires a careful assessment of clinical settings, data availability, and statistical methodology. For better use of external controls in oncology clinical trials, we recommend: prospective study designs to avoid selection bias, sufficient baseline data to ensure the comparability of study populations, consistent endpoint measurements to enable outcome comparison, robust statistical methodology for comparative analysis, and collaborative efforts of sponsors and regulators to establish regulatory frameworks.

Eco-efficiency assessment of disease-infected shrimp farming in Mexico using environmental impact assessment tools.

Mexico ranks second in shrimp (Litopenaeus vannamei) production of in Latin America with significant annual growth, however, during 2011 shrimp production fell by almost 50 % due to the presence of the white spot syndrome virus (WSSV). In this context, a life cycle analysis (LCA) and data envelopment analysis (DEA) were performed on 76 commercial farms severely affected by the presence of WSSV in northwestern Mexico. The application of this combined methodology allowed a detailed quantification of different environmental impact categories. During the presence of WSSV, there was a negative effect on the feed conversion ratio (FCR) (>40 %), higher consumption of seawater (38 %), and energy (38 %). Consequently, operational outputs related to the discharge of nitrogen and phosphorus increased by 60 and 57 %, respectively. Similarly, CO2 emissions, increased by 38 % relative to a typical year of production. Overall, the main critical points in the impact categories analyzed are related to food (98 %), use of diesel (23 %), and rearing (24 %), dominating pollutants emissions in all categories. Consequently, an improvement scenario was evaluated related to innovation in the formulation of foods supplied with immunostimulants, which confer protection against pathogenic microorganisms. This scenario lead to a reduction environmental impact of about 82 %. The results of this analysis will be a useful resource in the design of mitigation strategies with innovation processes that allow maintaining yields for shrimp producers in this region and at the same time reduce the environmental impacts generated.

Amphipterygium adstringens (Schltdl.) Schiede ex Standl (Anacardiaceae): An Endemic Plant with Relevant Pharmacological Properties.

Diseases, such as cancer, peptic ulcers, and diabetes, as well as those caused by drug-resistant infectious agents are examples of some of the world's major public health problems. Amphipterygium adstringens (Schltdl.) Schiede ex Standl is an endemic tree to Mexico. Its stem bark has been used medicinally since pre-Hispanic times, but in recent decades it has been scientifically proven that it has properties that help counteract some diseases; extracts with organic solvents of the plant are outstanding for their anticancer, gastroprotective, and antimicrobial properties; terpenes and long-chain phenols have been identified as the main active compounds. Currently, overharvesting is causing a sharp reduction in natural populations due to an increase in demand for the stem bark by people seeking to improve their health and by national and transnational companies seeking to market it. Because of the growing interest of the world population and the scientific community, we reviewed recent studies on the bioactive properties of A. adstringens. Through the orderly and critical compendium of the current knowledge of A. adstringens, we provide a reference for future studies aimed at the rational use and protection of this valuable endemic natural resource.

Endogenous Hormone Profile and Sugars Display Differential Distribution in Leaves and Pseudobulbs of Laelia anceps Plants Induced and Non-Induced to Flowering by Exogenous Gibberellic Acid.

A profile of endogenous hormones and sugars in leaves and pseudobulbs of Laelia anceps subsp. anceps (Orchidaceae) plants induced and non-induced to flowering by the effect of different doses of exogenous gibberellic acid (GA3), considering the current and back growth structures (CGS and BGS), were investigated. A factorial experiment with five doses of GA3 and two growth structures was designed. Adult plants with undifferentiated vegetative buds were selected and sprayed with doses of 0, 400, 600, 800, and 1000 mg GA3 L-1. The main results showed a strong interaction between GA3 dose and growth structures, which promoted the highest kinetin (KIN) concentration in CGS. Exogenous GA3 increased endogenous GA3 in leaves and pseudobulbs induced (I-Leaf and I-PSB) and non-induced (NI-Leaf and NI-PSB) to flowering. For sugar concentration, the 400 mg L-1 GA3 dose promotes significant interaction with the CGS in NI-PSB. In general, the hormone profile revealed opposite balances of endogenous hormone concentrations for KIN, zeatin (ZEA), trans-zeatin (T-ZEA), indoleacetic acid (IAA), indole-3-butyric acid (IBA) and GA3, not only for growth structures but also for vegetative organs analyzed, depending on whether the plants were induced or not induced to flowering, with the highest concentration of endogenous hormones in pseudobulbs. Likewise, different sugar concentration balances were observed. These balances of both endogenous hormones and sugars are likely to be involved in the flowering of L. anceps.

Novel translucent monolithic zirconia fixed restorations in the esthetic zone.

Novel translucent monolithic zirconia has improved optical properties, and it may fulfill patient's esthetic demands and overcome the chipping risk of bilayer metal-ceramic restorations. New zirconia's microstructures allow us to mimic natural teeth.

Dietary Use of Methionine Sources and Bacillus amyloliquefaciens CECT 5940 Influences Growth Performance, Hepatopancreatic Histology, Digestion, Immunity, and Digestive Microbiota of Litopenaeus vannamei Fed Reduced Fishmeal Diets.

An 8-week feeding trial investigated the effect of Fishmeal (FM) replacement by soybean meal (SBM) and poultry by-product meal (PBM) in diets supplemented with DL-Met, MET-MET (AQUAVI®), Bacillus amyloliquefaciens CECT 5940 (ECOBIOL®) and their combinations on growth performance and health of juvenile Litopenaeus vannamei. A total of six experimental diets were formulated according to L. vannamei nutritional requirements. A total of 480 shrimp (0.30 ± 0.04 g) were randomly distributed into 24 tanks (4 repetitions/each diet, 20 shrimp/tank). Shrimp were fed with control diet (CD; 200 g/Kg fishmeal) and five diets with 50% FM replacement supplemented with different methionine sources, probiotic (B. amyloliquefaciens CECT 5940) and their combinations: D1 (0.13% DL-MET), D2 (0.06% MET-MET), D3 (0.19% MET-MET), D4 (0.13% DL-MET plus 0.10% B. amyloliquefaciens CECT 5940 and D5 (0.06% MET-MET plus 0.10% B. amyloliquefaciens CECT 5940). Shrimp fed D3 and D5 had significantly higher final, weekly weight gain, and final biomass compared to shrimp fed CD (p < 0.05). Shrimp fed D2 to D5 increased the hepatopancreas epithelial cell height (p < 0.05). Digestive enzymatic activities were significantly increased in shrimp hepatopancreas' fed D3 (p < 0.05). Meanwhile, shrimp fed D1 had significant downregulation of immune-related genes (p < 0.05). Moreover, shrimp fed D3 and D5 increased the abundance of beneficial prokaryotic microorganisms such as Pseudoalteromonas and Demequina related to carbohydrate metabolism and immune stimulation. Also, shrimp fed D3 and D5 increased the abundance of beneficial eukaryotic microorganism as Aurantiochytrium and Aplanochytrium were related to eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) production which plays a role in growth promoting or boosting the immunity of aquatic organisms. Therefore, fishmeal could be partially substituted up to 50% by SBM and PBM in diets supplemented with 0.19% MET-MET (AQUAVI®) or 0.06% MET-MET (AQUAVI®) plus 0.10% B. amyloliquefaciens CECT 5940 (ECOBIOL®) and improve the productive performance, health, and immunity of white shrimp. Further research is necessary to investigate synergistic effects of amino acids and probiotics in farmed shrimp diets, as well as to evaluate how SBM and PBM influence the fatty acid composition of reduced fishmeal diets and shrimp muscle quality. Nevertheless, this information could be interesting to develop low fishmeal feeds for aquaculture without affecting the growth and welfare of aquatic organisms.

Chayote Fruit (Sechium edule var. virens levis) Development and the Effect of Growth Regulators on Seed Germination.

The chayote fruit is a nontraditional vegetable belonging to the Cucurbitaceae family. The fruit has an endocarpic recalcitrant seed that emerges postharvest, drastically shortening its shelf life. In this study, the changes during fruit and seed development before and after harvest (ah) are reported. Additionally, in order to investigate how growth regulators (GRs) affect seed germination, 2-cloroethylphosphonic acid (CPA) (200 µL L-1), gibberellic acid (GA3) (100 and 200 mg L-1), auxin (2,4-D) (0.5 and 1.0 mM), and abscisic acid (ABA) (0.5 and 1.0 mM) were applied after harvest. The results showed that the chayote fruit reached horticultural maturity at 21 days after anthesis, with a sigmoid trend: phase I featured slow growth and high transpiration; in phase II, growth was accelerated and accumulation of endosperm was observed; and in phase III, both growth rate and transpiration were reduced, soluble sugars increased, and the seed showed 25% cotyledon development. At day 13 ah, CPA, GA3, and 2,4-D (0.5 mM) increased seed germination, with values between 10 and 15 mm of the embryonary axis, and the treatments with 2,4-D (1 mM) and ABA (0.5 and 1.0 mM) retarded their growth (2-6 mm). This research allowed us to reveal the phenological phases and the shelf life of the chayote fruit, as well as the results of possible postharvest treatment with GRs; our results suggest that strategies to delay viviparism and prolong the shelf life of the fruit should be applied before 10 days ah, when the embryonic axis of the seed has not developed.

Anti-Virulence Properties of Plant Species: Correlation between In Vitro Activity and Efficacy in a Murine Model of Bacterial Infection.

Several plant extracts exhibit anti-virulence properties due to the interruption of bacterial quorum sensing (QS). However, studies on their effects at the preclinical level are scarce. Here, we used a murine model of abscess/necrosis induced by Pseudomonas aeruginosa to evaluate the anti-pathogenic efficacy of 24 plant extracts at a sub-inhibitory concentration. We analyzed their ability to inhibit QS-regulated virulence factors such as swarming, pyocyanin production, and secretion of the ExoU toxin via the type III secretion system (T3SS). Five of the seven extracts with the best anti-pathogenic activity reduced ExoU secretion, and the extracts of Diphysa americana and Hibiscus sabdariffa were identified as the most active. Therefore, the abscess/necrosis model allows identification of plant extracts that have the capacity to reduce pathogenicity of P. aeruginosa. Furthermore, we evaluated the activity of the plant extracts on Chromobacterium violaceum. T3SS (ΔescU) and QS (ΔcviI) mutant strains were assessed in both the abscess/necrosis and sepsis models. Only the ΔescU strain had lower pathogenicity in the animal models, although no activity of plant extracts was observed. These results demonstrate differences between the anti-virulence activity recorded in vitro and pathogenicity in vivo and between the roles of QS and T3S systems as virulence determinants.

Diagnostic concordance of pathological methods and reports of hematopathologists compared to local nonspecialized pathologists in the diagnosis of lymphoma in Mexico.

OBJECTIVES: To assess the concordance between lymphoma diagnoses made via tissue biopsy by local pathologists and also to assess the after review of these specimens by more specialized hematopathologists. METHODS: A prospective, non-interventional and multicenter study was conducted at seven sites in Mexico from January 2017 to October 2017. Eligible biopsies were sampled from patients with a previous diagnosis of lymphoma on lymph node biopsy or a diagnosis of extranodal lymphoma, with adequate amount and tissue preservation for the review analysis. The biopsy tissues reviewed by local pathologists were also reviewed by hematopathologists participating in the study. The concordance in diagnosis results was classified into three categories: diagnostic agreement, minor discrepancy and major discrepancy. RESULTS: Out of 111 samples received, 105 samples met the eligibility criteria and were included for full analysis. The median patient age (range) was 54 (16-94) years. A diagnostic agreement was observed in 23 (21.9%) biopsies, minor discrepancies were observed in 32 (30.5%) biopsies and major discrepancies were observed in 50 (47.6%) biopsies. Diagnostic concordance varied across the seven study sites; the rate of major discrepancies ranged from 0% to 100% and the rate of diagnostic agreement ranged from 0% to 81.8%. Out of the 105 reviewed biopsies, a total of 89 cases were diagnosed as lymphoma by hematopathologists. CONCLUSIONS: This study showed that major discrepancies were observed following the review by hematopathologists compared with that of the local pathologist's initial diagnosis in nearly one-half cases. In addition, there was a wide variation in the percentage of diagnostic agreements and discrepancies among different study sites.

Bioprospecting of Sechium spp. varieties for the selection of characters with pharmacological activity.

Bioprospecting identifies new sources of compounds with actual or potential economic value that come from biodiversity. An analysis was performed regarding bioprospecting purposes in ten genotypes of Sechium spp., through a meta-analysis of 20 information sources considering different variables: five morphological, 19 biochemical, anti-proliferative activity of extracts on five malignant cell lines, and 188 polymorphic bands of amplified fragment length polymorphisms, were used in order to identify the most relevant variables for the design of genetic interbreeding. Significant relationships between morphological and biochemical characters and anti-proliferative activity in cell lines were obtained, with five principal components for principal component analysis (SAS/ETS); variables were identified with a statistical significance (< 0.7 and Pearson values ≥ 0.7), with 80.81% of the accumulation of genetic variation and 110 genetic bands. Thirty-nine (39) variables were recovered using NTSYSpc software where 30 showed a Pearson correlation (> 0.5) and nine variables (< 0.05), Finally, using a cladistics analysis approach highlighted 65 genetic bands, in addition to color of the fruit, presence of thorns, bitter flavor, piriform and oblong shape, and also content of chlorophylls a and b, presence of cucurbitacins, and the IC50 effect of chayote extracts on the four cell lines.

Polycyclic Aromatic Hydrocarbon-DNA Adducts in Gulf of Mexico Sperm Whale Skin Biopsies Collected in 2012.

The northern Gulf of Mexico has a long history of polycyclic aromatic hydrocarbon (PAH) contamination from anthropogenic activities, natural oil seepages, and the 2010 Deepwater Horizon explosion and oil spill. The continental shelf of the same area is a known breeding ground for sperm whales (Physeter macrocephalus). To evaluate PAH-DNA damage, a biomarker for potential cancer risk, we compared skin biopsies collected from Gulf of Mexico sperm whales in 2012 with skin biopsies collected from sperm whales in areas of the Pacific Ocean in 1999-2001. All samples were obtained by crossbow and comprised both epidermis and subcutaneous blubber. To evaluate exposure, 7 carcinogenic PAHs were analyzed in lipids extracted from Pacific Ocean sperm whale blubber, pooled by sex, and location. To evaluate PAH-DNA damage, portions of all tissue samples were formalin-fixed, paraffin-embedded, sectioned, and examined for PAH-DNA adducts by immunohistochemistry (IHC) using an antiserum elicited against benzo[a]pyrene-modified DNA, which crossreacts with several high molecular weight carcinogenic PAHs bound to DNA. The IHC showed widespread epidermal nuclear localization of PAH-DNA adducts in the Gulf of Mexico whales (n = 15) but not in the Pacific Ocean whales (n = 4). A standard semiquantitative scoring system revealed significantly higher PAH-DNA adducts in the Gulf of Mexico whales compared to the whales from the Pacific Ocean study (p = .0002).

MOOC Learning Assessment in Clinical Settings: Analysis from Quality Dimensions.

Online learning is becoming a fundamental modality of learning in medical education, and can be of great help during global crisis like the current COVID-19 pandemic. The MOOC (massive open online course) mode of e-learning is increasing its penetration worldwide, as a valid teaching approach to reach large populations. A major challenge in clinical education is the assessment of medical students and residents in clinical settings, and there is substantial evidence that the current situation requires improvement. The goal of this study was to evaluate the quality dimensions of a MOOC titled "Learning assessment in clinical settings," developed by three Mexican universities in the Coursera platform. A mixed-method study design was used to assess the quality dimensions of the MOOC in two phases: pilot and implementation. The best-rated aspects were learning resources and pedagogical perspective, and those with opportunity for improvement were collaboration and time management. Assessment might be learned through a MOOC format, especially for participants willing to engage with educational technology and self-direction.

Natural Bioactive Compounds of Sechium spp. for Therapeutic and Nutraceutical Supplements.

Natural products are in great demand because certain secondary metabolites (SMs) are sources of antioxidants, flavorings, active substances, or anticancer agents with less aggressiveness and selectivity, among which triterpenes and flavonoids are of importance because they inhibit carcinogenesis. For Sechium spp. P. Br. (chayotes), there is scientific evidence of antiproliferative activity that has occurred when cancer cell lines have been treated with this fruit. In order to compare future therapeutic designs and identify new and ancestral characteristics, triterpenes and flavonoids were determined in contrasting Sechium genotypes. The obtained data were analyzed via a cladistics approach, with the aim of identifying the characteristics and state of phytochemicals and genetic variables. The concentrations of flavonoids and triterpenes were determined, and a more complex composition of secondary metabolites was found in the wild types as compared to their domesticated genotypes. Bitter fruits contained a higher number of SMs, followed by those with a neutral and sweet flavor. A cladogram showed the differentiation of the three groups based on the flavor of the fruits. The diversity of SMs decreases in evolutionary terms, in response to domestication and environmental adaptation. Therefore, genotypes can be feasibly selected based on fruit flavor for gross-breeding, and cytotoxicity can be reduced without losing possible therapeutic effects.

Conservative approach in a patient with multiple radiolucent periapical lesions using endodontics and surgery

Case report of a 43- year old male patient with multiple periapical radiolucent lesions caused by endodontic failure in teeth supporting a metalloceramic prosthetic rehabilitation, who came to the clinic to assess the possibility of keeping his teeth. After clinical and radiological examination with periapical x-rays and cone beam computer tomography (CBCT), we decided to use a combined endodontic-surgical approach. Clinical evolution was favourable, and the radiographic and tomographic controls showed complete healing of the periapical radiolucent lesions. Endodontic retreatment combined with periapical microsurgery are effective tools for conservative treatment of teeth with periapical lesions caused by endodontic failures. (AU)

Análisis de la generación de conocimiento en la Reserva de la Biosfera El Cielo, México y la vinculación con su programa de manejo / Analysis of knowledge generation in the El Cielo Biosphere Reserve, Mexico, and the link to its management program

Resumen La generación, sistematización y transferencia del conocimiento sobre la biodiversidad es un insumo fundamental para su conservación y la inclusión de la comunidad. La Reserva de la Biosfera de El Cielo (RBC), Tamaulipas, México es un área natural protegida por las características de sus recursos bióticos y abióticos. El objetivo de esta investigación fue caracterizar el estado actual del conocimiento generado sobre la Reserva de la Biosfera el Cielo y determinar su relación con su programa de manejo. Se realizó una búsqueda, clasificación y revisión cualitativa y cuantitativa de las fuentes primarias existentes en las bases de datos de Web of Science, Scopus y Redalyc. Esta información se contrastó con el contenido del Programa de Manejo de la RBC. Los resultados muestran asociación indirecta entre publicaciones y programa de manejo, con ausencia de publicaciones en los subprogramas de cultura, comunicación y gestión, así como la necesidad de sistematizar los temas abordados. El principal logro obtenido en este trabajo es la integración, mapeo y sistematización de publicaciones, lo que establece una línea base para estudios futuros. El conocimiento existente sobre la RBC publicado en revistas científicas, se elaboró desde un enfoque disciplinar en el campo de la biología. Existe evidencia de que fue utilizado para elaborar su más reciente programa de manejo y que impacta al menos en el 20 % de las acciones comprendidas en el documento; sin embargo, el proceso para la transferencia del conocimiento fue indirecto y se requieren nuevos enfoques transdisciplinares para abordar la problemática socio-ecológica existente.

Abstract The generation, systematization and knowledge transfer about biodiversity is a fundamental input for its conservation and the inclusion of the community. El Cielo Biosphere Reserve (ECBR) in Tamaulipas, Mexico, is a natural area protected due to the characteristics of its biotic and abiotic resources. The objective of this research was to characterize the current state of the generated knowledge about El Cielo Biosphere Reserve and its relationship with its management program. A qualitative and quantitative search, classification, and review of the primary sources in the Web of Science, Scopus, and Redalyc databases was performed. This information was contrasted with the content of the ECBR Management Program. Results show an indirect association between publications and the management program with the absence of publications in the culture, communication, and management subprograms. The need to systematize the addressed topics was also evident. The main achievement of this work is the integration, mapping, and systematization of publications, which establishes a baseline for future studies. The existing knowledge about ECBR, published in scientific journals, was conducted from a disciplinary approach in the field of Biology. There is evidence that it was used to prepare its most recent management program and that it impacts at least 20% of the actions included in the document. However, the process for the transfer of knowledge was indirect, and new transdisciplinary approaches are required to address the existing socio-ecological problems.