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BACKGROUND: Polymeric electrospun mats have been used as scaffolds in tissue engineering for the development of novel materials due to its characteristics. The usage of synthetic materials has gone in decline due to environmental problems associated with their synthesis and waste disposal. Biomaterials such as biopolymers have been used recently due to good compatibility on biological applications and sustainability. OBJECTIVE: The purpose of this work is to obtain novel materials based on synthetic and natural polymers for applications on tissue engineering. METHODS: Aloe vera mucilage was obtained, chemically characterized, and used as an active compound contained in electrospun mats. Polymeric scaffolds were obtained in single, coaxial and tri-layer structures, characterized and evaluated in cell culture. RESULTS: Mucilage loaded electrospun fibers showed good compatibility due to formation of hydrogen bonds between polymers and biomolecules from its structure, evidenced by FTIR spectra and thermal properties. Cell viability test showed that most of the obtained mats result on viability higher than 75%, resulting in nontoxic materials, ready to be used on scaffolding applications. CONCLUSION: Mucilage containing fibers resulted on materials with potential use on scaffolding applications due to their mechanical performance and cell viability results.

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In this study, the functionality of an elastomer composite material containing polypyrrole (PPy) as a stress sensor was evaluated. The material was prepared using the swelling method by diffusing the pyrrole monomer into the elastomer before polymerization. To achieve adequate diffusion, organic solvents with affinity for the elastomer were used. The resulting materials were characterized by scanning electron microscopy (SEM), surface electrical resistance, and thermal and mechanical properties for application as a stress sensor. The simultaneous change in electrical resistance and tension stress was measured using a digital multimeter with electrodes connected to the jaws of a universal mechanical testing machine. The influence of stress cycles on the piezoresistivity of the composite materials was investigated. The obtained PPy/NBR composite presented a good combination of electrical conductivity and mechanical properties. The strain at break remained with mild variation after coating with PPy.

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This study addresses the fabrication of extruded films using poly(lactic acid) (PLA) and chitosan, with and without maleic anhydride as a compatibilizing agent, for potential applications in disposable food packaging. These films underwent controlled conditions of UV irradiation, water condensation, and temperature variations in an accelerated weathering chamber. The investigation analyzed the effect of different exposure periods on the structural, morphological, mechanical, and thermal properties of the films. It was observed that PLA films exhibited a lower susceptibility to degradation compared to those containing chitosan. Specifically, the pure PLA film showed an increase in elastic modulus and strength during the initial 144 h of exposure, associated with cross-linking induced by UV radiation. On the other hand, film Q2 composed of PLA, chitosan, and maleic anhydride and Q1 without maleic anhydride experienced a tensile strength loss of over 50% after 244 h of exposure. The Q2 film exhibited greater homogeneity, leading to increased resistance to degradation compared to that of Q1. As the degradation time increased, both the Q1 and Q2 films demonstrated a decline in thermal stability. These films also exhibited alterations in crystallinity attributed to the chemo-crystallization process, along with fluctuations in the glass transition temperature and crystallization, particularly at 288 h.

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Photothermal nanocomposite hydrogels are promising materials for remotely triggering drug delivery by near-infrared (NIR) radiation stimuli. In this work, a novel hydrogel based on poly(vinyl alcohol), poly(vinyl methyl ether-alt-maleic acid), poly(vinyl methyl ether), and functionalized multiwalled carbon nanotubes (MWCNT-f) was prepared by the freeze/thaw method. A comparative characterization of materials (with and without MWCNT-f) was carried out by infrared spectroscopy, differential scanning calorimetry, scanning electron microscopy, mechanical assays, swelling kinetics measurements, and photothermal analysis under NIR irradiation. Hydrophilic chemotherapeutic 5-fluorouracil (5-FU) and hydrophobic ibuprofen drugs were independently loaded into hydrogels, and the drug release profiles were obtained under passive and NIR-irradiation conditions. The concentration-dependent cytotoxicity of materials was studied in vitro using noncancerous cells and cancer cells. Notable changes in the microstructure and physicochemical properties of hydrogels were observed by adding a low content (0.2 wt %) of MWCNT-f. The cumulative release amounts of 5-FU and ibuprofen from the hydrogel containing MWCNT-f were significantly increased by 21 and 39%, respectively, through the application of short-term NIR irradiation pulses. Appropriate concentrations of the nanocomposite hydrogel loaded with 5-FU produced cytotoxicity in cancer cells without affecting noncancerous cells. The overall properties of the MWCNT-f-containing hydrogel and its photothermal behavior make it an attractive material to promote the release of hydrophilic and hydrophobic drugs, depending on the treatment requirements.

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This research outlines the fabrication of polymeric membranes and films of poly(lactic acid) (PLA), prepared via electrospinning and extrusion, respectively. These materials were subsequently coated with polyaniline (PANi) by using the in situ chemical polymerization technique. Scanning electron microscopy micrographs revealed that the best coatings were achieved when 3 and 30 min of contact time with the monomeric solution were used for the membrane and film, respectively. Additionally, Fourier transform infrared spectra, thermogravimetric studies, and contact angle measurements demonstrated proper interaction between PLA and PANi. The findings of these studies suggest that PLA membranes and films can serve as suitable substrates for the deposition of PANi, and the composite materials hold potential for use in environmental remediation applications.

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INTRODUCTION: Endovascular Aortic Repair (EVAR) has become the standard management of Unruptured Infrarenal Abdominal Aortic Aneurysm (UIAAA); however, current evidence is limited and uncertain in our environment compared to Open repair. Our study aimed to determine the survival, short and long-term outcomes of EVAR vs. Open in a Peruvian cohort of UIAAA. METHODS: A single-center observational, analytical, longitudinal study using a retrospective registry of 251 patients treated (EVAR=205 vs Open=46) for UIAAA from 2000 to 2017. Variables considered were baseline, comorbidities, type of treatment, short-term (<30 days) and long-term (<5 years) outcomes, postoperative mortality according to the Vascular Quality Initiative (VQI) Risk Score, survival curves including reoperation-free rate and according to size (<65 mm vs. >65 mm) of long-term UIAAA. All variables were grouped according to the treatment performed (EVAR vs. Open) and we used the descriptive, multivariate, Cox regression, and Kaplan-Meier survival statistical analyses. RESULTS: 251 UIAAA were evaluated and the mean age was 74.5 years [±13.32], smoking, family members with UIAAA, and previous abdominal surgery were the main antecedents. Diabetes mellitus 2 was the main comorbidity; more than 50% of patients with UIAAA had diameters greater than 65 mm (p=0.021). The calculated mortality (VQI) was Open=2.21% vs. EVAR=1.65%. The outcomes in short-term were mortality (Open=2.92% vs. EVAR=0%; p=0.039), blood transfusion >4 Units (Open=72.68% vs. EVAR=17.39%; p=0.021) and overall hospital stay (Open=14 vs. EVAR=5 days; p=0.049. A reduction in mortality (HR 0.76, 95% CI, 0.62-0.96, p=0.045) and readmission for aneurysmal rupture was identified for EVAR (HR 0.81, 95% CI, 0.79-0.85, p=0.031). In long-term outcomes, mortality (Open=3.41% vs. EVAR=19.56%; p=0.047), aneurysmal rupture (Open=0% vs. EVAR 13.04%; p=0.032) and reinterventions (Open=2.43% vs. EVAR=10.86%; p=0.002). An 86% risk of mortality (HR 1.86, 95% CI, 1.32-2.38, p=0.039) and elevated risk of readmission for aneurysmal rupture was identified for EVAR (HR 2.21, 95% CI, 1.98-2.45, p=0.028). At 5 years, survival for Open=93.67% vs. EVAR=80.44% (p=0.043), reintervention-free survival for Open=89.26% vs. EVAR=47.82% (p=0.021), survival for treated IUAAA <65 mm for Open=95.77% vs. EVAR=63.63% (p=0.019) and >65 mm for Open=92.53% vs. EVAR=85.71% (p=0.059). CONCLUSION: EVAR has shown better short-term benefits and survival than Open management; however, the latter still prevails in the long term in our Peruvian UIAAA cohort. Further follow-up studies are required to demonstrate the long-term benefit of EVAR in our population.

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The preparation method of hydrogels has a significant effect on their structural and physicochemical properties. In this report, physically and chemically cross-linked poly(vinyl alcohol) (PVA) networks containing humic acid (HA) were alternatively prepared by autoclaving (AC) and through glutaraldehyde (GA) addition, respectively, for agricultural purposes. PVA/HA hydrogels were comparatively characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, mechanical assays, scanning electron microscopy, swelling kinetics measurements, and water retention tests in soil. AC hydrogels showed a more homogeneous porous microstructure, higher swelling levels, and a better capacity to preserve the humidity of soil than those obtained by adding GA. Both PVA/HA hydrogels exhibited no phytotoxicity on cultivation trials of Sorghum sp., but the plant growth was promoted with the GA-cross-linked network as compared to the effect of the AC sample. The release behavior of urea was modified according to the preparation method of the PVA/HA hydrogels. After 3 days of sustained urea release, 91% of the fertilizer was delivered from the AC hydrogel, whereas a lower amount of 56% was released for the GA-cross-linked hydrogel. Beyond the advantages of applying PVA/HA hydrogels in the agricultural field, an appropriate method of preparing these materials endows them with specific properties according to the requirements of the target crop.

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Betalains are bioactive compounds with attractive antioxidant properties for the food industry, endowing them with potential application in food coatings to maintain quality and extend shelf life. However, they have low stability to factors such as light, temperature, and humidity. An alternative to protect bioactive compounds is nanoencapsulation; one of the most used techniques to produce an encapsulation is coaxial electrospraying. In this research, the preparation and characterization of gelatin-betalain nanoparticles were carried out using the coaxial electrospray technique. Betalains were extracted from pitaya (Stenocereus thurberi) and encapsulated in gelatin. The obtained material was evaluated by SEM, FTIR, TGA, and DSC techniques and for its antioxidant capacity. By SEM, nanoparticles with spherical and monodisperse morphologies were observed, with betalain concentrations of 1 and 3% w/v and average diameters of 864 and 832 µm, respectively. By FTIR, the interaction between betalain and gelatin was observed through amino groups and hydrogen bonds. Likewise, the antioxidant activity of the betalains was maintained at the time of encapsulation, increasing the antioxidant activity as the concentration increased. The results of the DPPH, ABTS, and total phenols methods were 645.4592 µM T/g, 832.8863 ± 0.0110 µM T/g, and 59.8642 ± 0.0279 mg GAE/g for coaxial nanoparticles with 3% betalains, respectively. Therefore, the coaxial electrospray technique was useful for obtaining nanoparticles with good antioxidant properties, and due to the origin of its components and since the use of toxic solvents is not necessary in the technique, the material obtained can be considered food grade with potential application as a coating on functional foods.

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Natural cyclodextrins (CDs) can be formed by 6, 7, or 8 glucose molecules (α-, ß-, and γ-, respectively) linked in a ring, creating a cone shape. Its interior has an affinity for hydrophobic molecules, while the exterior is hydrophilic and can interact with water molecules. This feature has been used to develop active packaging applied to food, interacting with the product or its environment to improve one or more aspects of its quality or safety. It also provides monitoring information when food is optimal for consumption, as intelligent packaging is essential for the consumer and the merchant. Therefore, this review will focus on discerning which packaging is most appropriate for each situation, solubility and toxicological considerations, characterization techniques, effect on the guest properties, and other aspects related to forming the inclusion complex with bioactive molecules applied to packaging.

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This study focused on the quality loss inhibition of fish muscle during refrigerated storage. Two parallel experiments were carried out that were focused on the employment of pitaya (Stenocereus thurberi) extracts in biodegradable packing films. On the one hand, a pitaya-gelatin film was employed for hake (Merluccius merluccius) muscle storage. On the other hand, a pitaya-polylactic acid (PLA) film was used for Atlantic mackerel (Scomber scombrus) muscle storage. In both experiments, fish-packing systems were stored at 4 °C for 8 days. Quality loss was determined by lipid damage and microbial activity development. The presence of the pitaya extract led to an inhibitory effect (p < 0.05) on peroxide, fluorescent compound, and free fatty acid (FFA) values in the gelatin-hake system and to a lower (p < 0.05) formation of thiobarbituric acid reactive substances, fluorescent compounds, and FFAs in the PLA-mackerel system. Additionally, the inclusion of pitaya extracts in the packing films slowed down (p < 0.05) the growth of aerobes, anaerobes, psychrotrophs, and proteolytic bacteria in the case of the pitaya-gelatin films and of aerobes, anaerobes, and proteolytic bacteria in the case of pitaya-PLA films. The current preservative effects are explained on the basis of the preservative compound presence (betalains and phenolic compounds) in the pitaya extracts.

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Introducción: La detección del virus SARS-CoV-2, agente causal de la COVID-19, es determinante para disminuir la propagación de la actual pandemia. Si bien el procedimiento de elección es la determinación del ácido nucleico del virus mediante la reacción en cadena de la polimerasa, también es necesario disponer de pruebas rápidas, con alta sensibilidad y precisión. Objetivo: Analizar la validez diagnóstica de un ensayo rápido de antígeno SARS-CoV-2, utilizado para la detección de la COVID-19 en el policlínico "5 de Septiembre" del municipio Playa. Material y Métodos: Se realizó un estudio analítico de corte transversal con 590 pacientes atendidos en la consulta de infecciones respiratorias agudas, en el período de enero a agosto de 2021. La determinación de antígeno SARS-CoV-2 se realizó con un ensayo rápido y la confirmación se hizo mediante la reacción en cadena de la polimerasa. Resultados: La prueba rápida de antígeno tuvo una elevada sensibilidad (98,19 %) y especificidad (92,39 %). La concordancia de los resultados obtenidos entre ambas pruebas fue elevada (0,868). Las sintomatologías más frecuentes reportadas, fueron, cefalea (51,69 %), fiebre (39,15 %), tos (37,16 %), pérdida del gusto/olfato (34,06 %) y rinorrea (30,16 %). Conclusiones: El ensayo rápido de antígeno del SARS-CoV-2 usado para la detección de la COVID-19 demostró validez y puede ser utilizado para el diagnóstico de la enfermedad. Las sintomatologías cefalea, fiebre, tos, pérdida del gusto/olfato y rinorrea fueron las más frecuentes, reportadas en más de 30 de los casos.

Introduction: The detection of the SARS-CoV-2 virus, the causal agent of COVID-19, is decisive to reduce the spread of the current pandemic. Although the procedure of choice is the determination of the nucleic acid of the virus using the polymerase chain reaction, the availability of rapid, highly sensitive, and accurate tests is also necessary. Objective: To analyze the diagnostic validity of a SARS-CoV-2 antigen rapid diagnostic test for the detection of COVID-19 in the "5 de Septiembre" Polyclinic in Playa municipality. Material and Methods: A cross-sectional analytical study was carried out on 590 patients seen in the acute respiratory infections consulting room in the period from January to August 2021. The detection of the SARS-CoV-2 antigen was performed using a rapid test and it was confirmed by polymerase chain reaction. Results: The rapid antigen test had a high sensitivity (98.19%) and specificity (92.39%). The concordance of the results obtained from both tests was high (0.868). The most frequent reported symptoms were headache (51.69%), fever (39.15%), cough (37.16%), loss of taste/smell (34.06%), and runny nose (30.16%). Conclusions: The SARS-CoV-2 antigen rapid diagnostic test used for the detection of COVID-19 is valid and can be used in the diagnosis of the disease. Symptoms such as headache, fever, cough, loss of taste/smell, and runny nose were the most frequently reported in more than 30% of cases.

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INTRODUCTION: There is currently no universal and uniform pattern of peripheral arterial disease (PAD) in the lower limbs; however, it is influenced by various cardiovascular factors of the individual. The objective of this study was to identify the arteriographic patterns of PAD in the lower limbs according to cardiovascular factors in a Peruvian cohort of patients. METHODS: This is an analytical, observational, and retrospective study. The arteriographic patterns of PAD in the aortoiliac segment were analyzed with the TransAtlantic InterSociety Consensus (TASC-II) score and the Global Anatomic Staging System (GLASS) for the femoropopliteal (FP), infraopopliteal (IP), and pedial (P) segments in a Peruvian cohort from January 2018 to May 2021. RESULTS: 595 patients (833 extremities) were analyzed with a mean age of 67.54 ± 16.39 years, and the main cardiovascular factor was diabetes (65.04%). The patients older than 65 years with GLASS FP 4 (p = 0.042), IP 0 (p = 0.004), and P2 (p = 0.047) presented significant findings: in men and women with GLASS IP 4 (p = 0.031) and P 2 (p = 0.045); diabetes with TASC-II A (p = 0.031), GLASS FP 4 (p = 0.038), IP 4 (p = 0.009), and P2 (p = 0.003); dyslipidemia with TASC-II D (p = 0.027), GLASS FP 4 (p = 0.038), IP 0 (p = 0.009), and P0 (p = 0.003); smoking with TASC-II D (p = 0.001), GLASS FP 4 (p = 0.049) and IP 0 (p = 0.008); chronic coronary disease with GLASS IP 4 (p = 0.049) and P2 (p = 0.037); chronic kidney disease with GLASS FP 4 (p=0.047), IP 4 (p = 0.004), and P2 (p = 0.016); and previous amputation history with GLASS IP 4 (p = 0.015) and P2 (p = 0.039). The most frequent arteriographic pattern of PAD in the lower limbs of our cohort was TASC-II A, GLASS FP 0 and 4, IP 0, and P2 (p = 0.047). CONCLUSION: Our work will allow the limb salvage teams to understand the behavior of PAD affectation in the population of our environment, allowing a timely control of cardiovascular risk factors, adequate revascularization planning, and a significant reduction in the risk of loss of limb.

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The objective of this paper was to report the effect of ionic liquids (ILs) in the elaboration of nanofibers of cellulose bagasse from Agave tequilana Weber var. azul by the electrospinning method. The ILs used were 1-butyl-3-methylimidazolium chloride (BMIMCl), and DMSO was added as co-solvent. To observe the effect of ILs, this solvent was compared with the organic solvent TriFluorAcetic acid (TFA). The nanofibers were characterized by transmission electron microscopy (TEM), X-ray, Fourier transform-infrared using attenuated total reflection (FTIR-ATR) spectroscopy, and thermogravimetric analysis (TGA). TEM showed different diameters (ranging from 35 to 76 nm) of cellulose nanofibers with ILs (CN ILs). According to X-ray diffraction, a notable decrease of the crystalline structure of cellulose treated with ILs was observed, while FTIR-ATR showed two bands that exhibit the physical interaction between cellulose nanofibers and ILs. TGA revealed that CN ILs exhibit enhanced thermal properties due to low or null cellulose crystallinity. CN ILs showed better characteristics in all analyses than nanofibers elaborated with TFA organic solvent. Therefore, CN ILs provide new alternatives for cellulose bagasse. Due to their small particle size, CN ILs could have several applications, including in food, pharmaceutical, textile, and material areas, among others.

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This study describes the preparation and characterization of eggplant peel extract-loaded electrospun gelatin nanofiber and study of its in vitro release. Results obtained by scanning electron microscopy (SEM) and transmission electronic microscopy (TEM) micrograph revealed that eggplant peel extract-loaded electrospun gelatin nanofiber is in nanometric range with an average diameter 606.7 ± 184.5 and 643.6 ± 186.7 nm for 20 and 33.3 mg mL-1 of extract addition, respectively. Moreover, the incorporation of extract improved morphology by being smooth, homogeneous, and without account formation compared to nanofibers without extract (control). Fourier transform-infrared (FT-IR) spectra indicated that interaction exists between electrospun gelatin nanofiber and eggplant peel extract by hydrogen bond interactions, mainly. Electrospun gelatin nanofibers showed encapsulation efficiency greater than 90% of extract and a maximum release of 95 and 80% for the medium at pH 1.5 and 7.5, respectively. Therefore, the electrospinning technique is a good alternative for the conservation of bioactive compounds present in the eggplant peel through electrospun gelatin nanofiber.

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The aim of this work was to use glycerol (Gly) and sorbitol (Sor) as plasticizers with oxidized starch potato (OS) to produce biodegradable and environmentally friendly films, and to demonstrate the resulting physicochemical and functional viability without subtracting the organoleptic characteristics of the food. Analyses by water vapor permeability (WVP), attenuated total reflection Fourier transform infrared spectra (ATR-FTIR), scanning electron microscopy (SEM), tensile strength (TS), and transparency (UV) showed that the best film result was with 1.5 g of Gly and 2.0 g of Sor, conferred shine, elasticity 19.42 ± 6.20%, and mechanical support. The starch oxidized to 2.5%, contributing a greater transparency of 0.33 ± 0.12 and solubility of 78.90 ± 0.94%, as well as less permeability to water vapor 6.22 ± 0.38 gmm-2 d-1 kPa-1. The films obtained provide an alternative for use in food due to their organic compounds, excellent visual presentation, and barrier characteristics that maintain their integrity and, therefore, their functionality.

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The SAFARI technique or Subintimal Arterial Flossing with Antegrade-Retrograde Intervention is an endovascular procedure that allows recanalization of Chronic Total Occlusive (CTO) lesions when conventional subintimal angioplasty is unsuccessful. Retrograde access is usually obtained through the popliteal, anterior tibial, dorsalis pedis artery, or posterior tibial arteries and may potentially provide more options for endovascular interventions in limb salvage. The case of an 81-year-old man with a history of uncontrolled hypertension, diabetes mellitus, and dyslipidemia is presented. He presented with a cutaneous ulcer on the right lower limb with torpid evolution and poor healing. The Doppler ultrasound and arteriographic study revealed a CTO lesion of the popliteal artery that was not a candidate for antegrade endovascular revascularization, but was successfully treated using the SAFARI technique. The patient had no perioperative complications, the wound showed better healing, and he was discharged with an indication of daily dressings and control by an external outpatient clinic.

A técnica SAFARI, ou Subintimal Arterial Flossing with Antegrade-Retrograde Intervention, é um procedimento endovascular que permite a recanalização de lesões por oclusão total crônica (OTC) em caso de fracasso da angioplastia subintimal convencional. O acesso retrógrado é geralmente obtido através da artéria poplítea, tibial anterior, pediosa ou tibial posterior e pode fornecer mais alternativas de intervenções endovasculares para o salvamento do membro. É apresentado o caso de um homem de 81 anos com histórico de hipertenção não controlada, diabetes melito e dislipidemia. Ele apresentava uma lesão ulcerativa cutânea no membro inferior direito com evolução tórpida e má cicatrização. O ultrassom Doppler e o estudo arteriográfico revelaram uma lesão por OTC na artéria poplítea. O paciente não era candidato a revascularização endovascular anterógrada; sendo assim, esta foi realizada com successo utilizando a técnica SAFARI. O paciente não apresentou complicações perioperatórias e recebeu alta com indicação de cuidados diários com a ferida e controle em um ambulatório externo. Além disso, a ferida apresentou melhor cicatrização.

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Abstract Introduction: Despite extensive science-based conservation policy recommendations, with fewer than 20 individuals remaining, the vaquita (Phocoena sinus) -endemic to the Gulf of California- is the world's most endangered marine mammal due to incidental catch in fishing nets and whether it can recover is unclear. Objective: Assess expectations for vaquita over the next two decades. Methods: We identified factors affecting the vaquita, constructed life tables, derived demographic parameters for different scenarios and conducted a population viability analysis using stochastic age-structured matrix Leslie models. Results: Analytical results indicate that the vaquita net growth rate is particularly sensitive to juvenile survival. We find that intensive, ongoing bycatch in gillnets used to poach totoaba (Totoaba macdonaldi) over the past decade brought the vaquita population to its current critically low size. Currently this seems to be exacerbated by demographic stochasticity and a potential Allee effect. Conclusions: If totoaba poaching is eliminated immediately, demographically, vaquita can recover; its long-term survival will depend on its uncertain genetic status, although a recent study found encouraging results in this regard.

Resumen Introducción: Pese a las acciones de conservación basadas en la ciencia y las políticas recomendadas, con menos de 20 individuos sobrevivientes, la vaquita (Phocoena sinus) -endémica del Golfo de California- es el mamífero marino más amenazado del mundo debido a su muerte incidental en redes de pesca; una pregunta relevante es si su población se puede recuperar. Objetivo: Evaluar las expectativas para la vaquita marina durante los próximos 20 años. Métodos: Identificamos los factores que afectan a la vaquita marina, construimos tablas de vida, derivamos parámetros demográficos para diferentes escenarios y realizamos un análisis de viabilidad poblacional utilizando matrices estocásticas de Leslie, estructuradas por edad. Resultados: La tasa de crecimiento neto de la vaquita es muy sensible a la supervivencia de los juveniles. Encontramos que la captura incidental intensiva y continua en redes de enmalle para la pesca furtiva de totoaba (Totoaba macdonaldi) durante la última década llevó a la población de vaquitas a su actual estado crítico. Esto parece agravarse por la estocasticidad demográfica y un potencial efecto Allee. Conclusiones: Si la pesca furtiva de totoaba se elimina de inmediato, demográficamente la vaquita puede recuperarse; su supervivencia a largo plazo dependerá de su incierto estatus genético, aunque los resultados de un estudio reciente son alentadores en este sentido.

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Silver nanoparticles have high potential for application in food industry, as they have the ability to inhibit a wide range of bacteria of pathogenic and spoilage origin. They can be obtained from different methods classified in physical and chemical and which are aggressive with the environment since they produce toxic waste. Nowadays, environmentally friendly methods such as green synthesis can be used, through the use of agri-food waste. The use of these wastes is a more sustainable method, because it reduces the environmental pollution, at the same time that silver nanoparticles are obtained. The aim of the present study is the green synthesis of silver nanoparticles using safflower (Carthamus tinctorius L.) aqueous extract from waste and its antibacterial activity on Staphylococcus aureus (Gram positive) and Pseudomonas fluorescens (Gram negative). The analyses by TEM showed that the as-synthesized silver nanoparticles were uniform and spherical particles with an average diameter of 8.67 ± 4.7 nm and confirmed by SEM. The electron diffraction and TEM analyses showed the characteristic crystallinity of silver nanoparticles. FTIR spectroscopy confirmed that various functional groups were responsible for reducing and stabilizing during the biosynthesis process. Nanoparticles inhibited the growth of both types of bacteria from the lowest concentration evaluated (0.9 µg/mL). We conclude that silver nanoparticles synthesized in the present study have potential application as antibacterial agents in food and medicine industry.

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Vascular wilt, caused by the pathogen Fusarium oxysporum f. sp. physali (Foph), is a major disease of cape gooseberry (Physalis peruviana L.) in Andean countries. Despite the economic losses caused by this disease, there are few studies related to molecular mechanisms in the P. peruviana-Foph pathosystem as a useful tool for crop improvement. This study evaluates eight candidate genes associated with this pathosystem, using real-time quantitative PCR (RT-qPCR). The genes were identified and selected from 1,653 differentially expressed genes (DEGs) derived from RNA-Seq analysis and from a previous genome-wide association study (GWAS) of this plant-pathogen interaction. Based on the RT-qPCR analysis, the tubuline (TUB) reference gene was selected for its highly stable expression in cape gooseberry. The RT-qPCR validation of the candidate genes revealed the biological variation in their expression according to their known biological function. Three genes related to the first line of resistance/defense responses were highly expressed earlier during infection in a susceptible genotype, while three others were overexpressed later, mostly in the tolerant genotype. These genes are mainly involved in signaling pathways after pathogen recognition, mediated by hormones such as ethylene and salicylic acid. This study provided the first insight to uncover the molecular mechanism from the P. peruviana-Foph pathosystem. The genes validated here have important implications in the disease progress and allow a better understanding of the defense response in cape gooseberry at the molecular level. Derived molecular markers from these genes could facilitate the identification of tolerant/susceptible genotypes for use in breeding schemes.

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Introducción: El neumomediastino es una patología poco frecuente y rara. Las manifestaciones radiológicas típicas en los pacientes en neumonía por SARS-CoV-2 consiste en la presencia de opacidades pulmonares bilaterales, de distribución periférica. En una reciente serie de pacientes con COVID-19 indica que el 1% de los pacientes pueden desarrollar neumomediastino espontáneo como complicación, generalmente es de curso benigno y no se aclara aún que ello puede suponer un indicador de agravamiento. Caso Clínico: Se trata de un paciente varón de 43 años que presentó un tiempo de enfermedad de 15 días caracterizado por dolor faríngeo, fiebre, dolor torácico y dificultad respiratoria, recibiendo múltiples esquemas de tratamiento tanto antiviral y antibióticos sin respuesta, por lo que acudió al Hospital Rebagliati donde se le encontró insuficiencia respiratoria, hipoxemia y sepsis. Su tomografía fue compatible con infiltrado en vidrio deslustrado, áreas de consolidación pulmonar bilateral y neumomediastino. No requirió tratamiento quirúrgico y evolucionó favorablemente a la neumonía con disminución de marcadores inflamatorios y remisión de neumomediastino en control tomográfico. Conclusión: Este reporte resalta que en la infección por COVID-19 las complicaciones pulmonares a tener en cuenta son la neumonía bilateral, coinfección bacteriana, sepsis y neumomediastino espontáneo.

Introduction: Pneumomediastinum is an infrequent and rare pathology. The typical radiological manifestations in patients with SARS-CoV-2 pneumonia consist of the presence of bilateral pulmonary opacities, of peripheral distribution. In a recent series of patients with COVID-19, it indicates that 1% of patients can develop spontaneous pneumomediastinum as a complication, it is generally benign and it is not yet clear that this may be an indicator of worsening. Clinical Case: This is a 43-year-old male patient who presented a 15-day illness characterized by pharyngeal pain, fever, chest pain and respiratory distress, receiving multiple antiviral and antibiotic treatment schemes without response, for which he attended to Rebagliati Hospital where he was found respiratory failure, hypoxemia and sepsis. His tomography was compatible with ground glass infiltrate, areas of bilateral lung consolidation, and pneumomediastinum. It did not require surgical treatment and it evolved favorably to pneumonia with a decrease in inflammatory markers and remission of pneumomediastinum in tomographic control. Conclusion: This report highlights that in COVID-19 infection the pulmonary complications to take into account are bilateral pneumonia, bacterial coinfection, sepsis and spontaneous pneumomediastinum.