Eco-Friendly Design of Chitosan-Based Films with Biodegradable Properties as an Alternative to Low-Density Polyethylene Packaging.

Biopolymer-based films are a promising alternative for the food packaging industry, in which petrochemical-based polymers like low-density polyethylene (LDPE) are commanding attention because of their high pollution levels. In this research, a biopolymer-based film made of chitosan (CS), gelatin (GEL), and glycerol (GLY) was designed. A Response Surface Methodology (RSM) analysis was performed to determine the chitosan, gelatin, and glycerol content that improved the mechanical properties selected as response variables (thickness, tensile strength (TS), and elongation at break (EAB). The content of CS (1.1% w/v), GEL (1.1% w/v), and GLY (0.4% w/v) in the film-forming solution guarantees an optimized film (OPT-F) with a 0.046 ± 0.003 mm thickness, 11.48 ± 1.42 mPa TS, and 2.6 ± 0.3% EAB. The OPT-F was characterized in terms of thermal, optical, and biodegradability properties compared to LDPE films. Thermogravimetric analysis (TGA) revealed that the OPT-F was thermally stable at temperatures below 300 °C, which is relevant to thermal processes in the food industry of packaging. The reduced water solubility (WS) (24.34 ± 2.47%) and the improved biodegradability properties (7.1%) compared with LDPE suggests that the biopolymer-based film obtained has potential applications in the food industry as a novel packaging material and can serve as a basis for the design of bioactive packaging.

CROCuS, a Phase II Study Evaluating the Antiviral Activity, Clinical Outcomes, and Safety of Rilematovir in Children Aged ≥ 28 Days and ≤ 3 Years with Acute Respiratory Tract Infection Due to Respiratory Syncytial Virus.

BACKGROUND: Respiratory syncytial virus (RSV) causes significant morbidity and mortality in children aged ≤ 5 years and adults aged ≥ 60 years worldwide. Despite this, RSV-specific therapeutic options are limited. Rilematovir is an investigational, orally administered inhibitor of RSV fusion protein-mediated viral entry. OBJECTIVE: To establish the antiviral activity, clinical outcomes, safety, and tolerability of rilematovir (low or high dose) in children aged ≥ 28 days and ≤ 3 years with RSV disease. METHODS: CROCuS was a multicenter, international, double-blind, placebo-controlled, randomized, adaptive phase II study, wherein children aged ≥ 28 days and ≤ 3 years with confirmed RSV infection who were either hospitalized (Cohort 1) or treated as outpatients (Cohort 2) were randomized (1:1:1) to receive rilematovir (low or high dose) or placebo. Study treatment was administered daily as an oral suspension from days 1 to 7, with dosing based on weight and age groups. The primary objective was to establish antiviral activity of rilematovir by evaluating the area under the plasma concentration-time curve of RSV viral load in nasal secretions from baseline through day 5. Severity and duration of RSV signs and symptoms and the safety and tolerability of rilematovir were also assessed through day 28 (± 3). RESULTS: In total, 246 patients were randomized, treated, and included in the safety analysis population (Cohort 1: 147; Cohort 2: 99). Of these, 231 were included in the intent-to-treat-infected analysis population (Cohort 1: 138; Cohort 2: 93). In both cohorts, demographics were generally similar across treatment groups. In both cohorts combined, the difference (95% confidence interval) in the mean area under the plasma concentration-time curve of RSV RNA viral load through day 5 was - 1.25 (- 2.672, 0.164) and - 1.23 (- 2.679, 0.227) log10 copies∙days/mL for the rilematovir low-dose group and the rilematovir high-dose group, respectively, when compared with placebo. The estimated Kaplan-Meier median (95% confidence interval) time to resolution of key RSV symptoms in the rilematovir low-dose, rilematovir high-dose, and placebo groups of Cohort 1 was 6.01 (4.24, 7.25), 5.82 (4.03, 8.18), and 7.05 (5.34, 8.97) days, respectively; in Cohort 2, estimates were 6.45 (4.81, 9.70), 6.26 (5.41, 7.84), and 5.85 (3.90, 8.27) days, respectively. A similar incidence of adverse events was reported in patients treated with rilematovir and placebo in Cohort 1 (rilematovir: 61.9%; placebo: 58.0%) and Cohort 2 (rilematovir: 50.8%; placebo: 47.1%), with most reported as grade 1 or 2 and none leading to study discontinuation. The study was terminated prematurely, as the sponsor made a non-safety-related strategic decision to discontinue rilematovir development prior to full recruitment of Cohort 2. CONCLUSIONS: Data from the combined cohort suggest that rilematovir has a small but favorable antiviral effect of indeterminate clinical relevance compared with placebo, as well as a favorable safety profile. Safe and effective therapeutic options for RSV in infants and young children remain an unmet need. CLINICAL TRIAL REGISTRATION: EudraCT Number: 2016-003642-93; ClinicalTrials.gov Identifier: NCT03656510. First posted date: 4 September, 2018.

High-Throughput Screening Method Using Escherichia coli Keio Mutants for Assessing Primary Damage Mechanism of Antimicrobials.

The Escherichia coli Keio mutant collection has been a tool for assessing the role of specific genes and determining their role in E. coli physiology and uncovering novel functions. In this work, specific mutants in the DNA repair pathways and oxidative stress response were evaluated to identify the primary targets of silver nanoparticles (NPs) and their mechanism of action. The results presented in this work suggest that NPs mainly target DNA via double-strand breaks and base modifications since the recA, uvrC, mutL, and nfo mutants rendered the most susceptible phenotype, rather than involving the oxidative stress response. Concomitantly, during the establishment of the control conditions for each mutant, the katG and sodA mutants showed a hypersensitive phenotype to mitomycin C, an alkylating agent. Thus, we propose that KatG catalase plays a key role as a cellular chaperone, as reported previously for the filamentous fungus Neurospora crassa, a large subunit catalase. The Keio collection mutants may also be a key tool for assessing the resistance mechanism to metallic NPs by using their potential to identify novel pathways involved in the resistance to NPs.

New records of Rhipicephalus linnaei infected by Rickettsia massiliae from Central Mexico.

BACKGROUND: On the American continent, Rhipicephalus sanguineus s.l. comprises two species: Rhipicephalus linnaei and R. sanguineus s.s. Each species has been identified as a potential vector of at least one of five species of pathogenic bacteria of the genus Rickettsia. In particular, Rickettsia massiliae is one of three species with the greatest importance in public health at the continental level. In Mexico, this species is reported exclusively in the Nearctic states of Baja California and Chihuahua. AIM: For this reason, the aim of this work was to provide new records of R. massiliae for the centre of the country derived from active acarological surveillance. MATERIALS AND METHODS: During the period of February-October 2019, 29 dogs from six municipalities in the state of Morelos were sampled. Hosts were visually inspected, and ticks were recovered and identified morphologically and molecularly by amplification of the 16S rDNA gene. Subsequently, five genes from members of the genus Rickettsia were amplified and sequenced. RESULTS: A total of 229 (117♀, 98♂ and 14 N) ticks identified as R. linnaei were recovered, two of which were positive for R. massiliae strains related to those recovered from Argentina and the United States. CONCLUSIONS: This work provides the second record of R. massiliae infecting R. linnaei in Mexico and the Americas, increasing the geographic distribution of this Rickettsia species in the Neotropical region, and providing information on the possible role of R. linnaei as a potential vector of this microorganism.

Surface Functionalization and Escherichia coli Detection Using Surface-Enhanced Raman Spectroscopy Driven by Functional Organic Polymer/Gold Nanofilm-Based Microfluidic Chip.

In this work, a microfluidic prototype based on polymeric materials was developed to monitor surface processes using surface-enhanced Raman spectroscopy (SERS), keeping the reagents free of environmental contamination. The prototype was fabricated on poly(methyl methacrylic acid) (PMMA). A micrometric membrane of a functional organic polymer (FOP) based on p-terphenyl and bromopyruvic acid monomers was formed on the PMMA surface to promote the formation of metal nanoclusters. Au nanosized film was deposited on the FOP membrane to give rise to the SERS effect. A microchannel was formed on another piece of PMMA using micromachining. A representative 3D model of the prototype layer arrangement was built and simulated in COMSOL Multiphysics® to approximate the electric field distribution and calculate the power enhancement factor as the Au film changes over time. The fabrication process was characterized using UV-visible and Raman spectroscopies and XPS. The prototype was tested using a Raman microscope and liquid solutions of cysteamine and Escherichia coli (E. coli). The simulation results demonstrated that the morphological characteristics of the Au layer give rise to the SERS effect, and the power enhancement factor reaches values as high as 8.8 × 105 on the FOP surface. The characterization results showed the formation of the FOP and the Au film on PMMA and the surface functionalization with amine groups. The Raman spectra of the prototype showed temporal evolution as different compounds were deposited on the upper wall of the microchannel. Characteristic peaks associated with these compounds were detected with continuous monitoring over time. This prototype offers many benefits for applications like monitoring biological processes. Some advantages include timely surface evaluation while avoiding environmental harm, decreased use of reagents and samples, minimal interference with the process by measuring, and detecting microorganisms in just 1 h, as demonstrated with the E. coli sample.

Peptides with biological and technofunctional properties produced by bromelain hydrolysis of proteins from different sources: A review.

Bromelains are cysteine peptidases with endopeptidase action (a subfamily of papains), obtained from different parts of vegetable belonging to the Bromeliaceae family. They have some intrinsic medical activity, but this review is focused on their application (individually or mixed with other proteases) to produce bioactive peptides. When compared to other proteases, perhaps due to the fact that they are commercialized as an extract containing several proteases, the hydrolysates produced by this enzyme tends to have higher bioactivities than other common proteases. The peptides and the intensity of their final properties depend on the substrate protein and reaction conditions, being the degree of hydrolysis a determining parameter (but not always positive or negative). The produced peptides may have diverse activities such as antioxidant, antitumoral, antihypertensive or antimicrobial ones, among others or they may be utilized to improve the organoleptic properties of foods and feeds. Evolution of the use of this enzyme in this application is proposed to be based on a more intense direct application of Bromeliaceae extract, without the cost associated to enzyme purification, and the use of immobilized biocatalysts of the enzyme by simplifying the enzyme recovery and reuse, and also making the sequential hydrolysis using diverse proteases possible.

Tick-associated diseases identified from hunting dogs during the COVID-19 pandemic in a Mayan community in Yucatan, Mexico.

Background: Hunting activity in the Mayan communities has increased due to COVID-19 and domestic dogs have gained more importance. Due to their proximity to humans, domestic dogs are a bridge between tick-borne diseases (TBDs) and humans and their peri-domestic environment. In Mexico, and especially in rural regions, there were not adequate records of TBDs during the SARS-CoV-2 pandemic. Aim: Identify TBD of ticks collected during the COVID-19 pandemic in a rural community. Methods: Tick capture was carried out in March 2021, in Teabo, Yucatan. Ticks were removed using from domestic dogs and placed in ethanol. Collected ticks were morphologically identified and underwent DNA extraction and a partial segment of the mitochondrial 16S-rDNA gene was amplified to corroborate the tick species. The DNA was screened for the presence of Anaplasma spp., Borrelia spp., Ehrlichia spp., and Rickettsia spp. Purified amplification products were submitted for sequencing and the results were compared to those deposited in GenBank using BLAST. Results: We collected 33 ectoparasites, Ixodes affinis, Rhipicephalus sanguineus, Rhipicephalus microplus, and Amblyomma mixtum on 11 hunting dogs. The most frequent ectoparasite was R. sanguineus (66%). We detected the presence of DNA of Rickettsia endosymbiont in I. affinis and Anaplasma platys in R. sanguineus. Rickettsia endosymbiont presented a similarity of 100% with the partial sequence of R. endosymbiont of I. affinis isolate IACACTM001 16S ribosomal RNA gene and the sequence of A. platys had a similarity of 100% with the partial sequence of the isolate 23-33TX 16S ribosomal RNA gene of A. platys from dogs from Texas, USA and with the partial sequence of the isolate L134 16S ribosomal RNA gene of Ehrlichia canis from dogs from Piura, Peru. Conclusion: We confirmed for the first time the presence of A. platys in R. sanguineus and R. endosymbiont in I. affinis ticks from dogs in the state of Yucatan.

Comparison of Climate Change Scenarios of Rhipicephalus sanguineus sensu lato (Latreille 1806) from México and the Boarders with Central America and the United States.

In America, the presence of Rhipicephalus sanguineus sensu stricto and Rhipicephalus linnaei has been confirmed. Both species are found in sympatry in the southern United States, northern Mexico, southern Brazil, and Argentina. The objective of this work is to evaluate the projection of the potential distribution of the ecological niche of Rhipicephalus sanguineus sensu lato in two climate change scenarios in Mexico and the border with Central America and the United States. Initially, a database of personal collections of the authors, GBIF, Institute of Epidemiological Diagnosis and Reference, and scientific articles was built. The ENMs were projected for the current period and two future scenarios: RCP and SSP used for the kuenm R package, the ecological niche of R. sanguineus s.l. It is distributed throughout the Mexico and Texas (United States), along with the border areas between Central America, Mexico, and the United States. Finally, it is observed that the ecological niche of R. sanguineus s.l. in the current period coincides in three degrees with the routes of human migration. Based on this information, and mainly on the flow of migrants from Central America to the United States, the risk of a greater gene flow in this area increases, so the risk relating to this border is a latent point that must be analyzed.

A story of a lone star tick: an imported case of Amblyomma americanum (Linnaeus, 1758) infected with Rickettsia amblyommatis that parasitized a US traveler returning to Mexico.

In this study, we report the presence of a female Amblyomma americanum tick attached to a former resident of the East Coast of the United States who moved to Mexico city. The amplification and sequencing of gene fragments of the 16S-rDNA and cytochrome c oxidase subunit 1 corroborated the identification of the species of the tick. Additionally, the presence of DNA of Rickettsia amblyommatis was confirmed. This work is the first report of an exotic tick of the genus Amblyomma in a traveler from the US to Mexico and represents the second record of an imported tick attached to humans in Mexico.

Sargassum natans I Algae: An Alternative for a Greener Approach for the Synthesis of ZnO Nanostructures with Biological and Environmental Applications.

In this work, the influence of the Sargassum natans I alga extract on the morphological characteristics of synthesized ZnO nanostructures, with potential biological and environmental applications, was evaluated. For this purpose, different ZnO geometries were synthesized by the co-precipitation method, using Sargassum natans I alga extract as stabilizing agent. Four extract volumes (5, 10, 20, and 50 mL) were evaluated to obtain the different nanostructures. Moreover, a sample by chemical synthesis, without the addition of extract, was prepared. The characterization of the ZnO samples was carried out by UV-Vis spectroscopy, FT-IR spectroscopy, X-ray diffraction, and scanning electron microscopy. The results showed that the Sargassum alga extract has a fundamental role in the stabilization process of the ZnO nanoparticles. In addition, it was shown that the increase in the Sargassum alga extract leads to preferential growth and arrangement, obtaining well-defined shaped particles. ZnO nanostructures demonstrated significant anti-inflammatory response by the in vitro egg albumin protein denaturation for biological purposes. Additionally, quantitative antibacterial analysis (AA) showed that the ZnO nanostructures synthesized with 10 and 20 mL of extract demonstrated high AA against Gram (+) S. aureus and moderate AA behavior against Gram (-) P. aeruginosa, depending on the ZnO arrangement induced by the Sargassum natans I alga extract and the nanoparticles' concentration (ca. 3200 µg/mL). Additionally, ZnO samples were evaluated as photocatalytic materials through the degradation of organic dyes. Complete degradation of both methyl violet and malachite green were achieved using the ZnO sample synthesized with 50 mL of extract. In all cases, the well-defined morphology of ZnO induced by the Sargassum natans I alga extract played a key role in the combined biological/environmental performance.

Compra compulsiva: revisión bibliométrica de la productividad científica desde 1985 hasta 2020 / Compulsive buying: Bibliometric review of scientific productivity from 1985 to 2020

Resumen En la sociedad de consumo, los deseos se transforman en necesidades y esto incide en la emergencia de compra compulsiva y sus efectos negativos a nivel personal y social. Por ello se requiere un esfuerzo de análisis y síntesis sobre el conocimiento científico existente, que mejore la comprensión del área. El objetivo es analizar el desarrollo de la producción científica sobre la compra compulsiva. Los criterios de inclusión fueron: artículos empíricos individuales y revisiones, que abarcaran hasta el año 2020 y sin sesgos de idioma. Se trabajó con las bases de datos Web of Science, Scopus y PsycINFO. Mediante un análisis bibliométrico -con criterios PRISMA- y utilizando el gestor de referencias EndNote X9, se localizaron 971 publicaciones. Los resultados señalan: un aumento de la productividad desde 2005; el inglés es el idioma prevalente de las publicaciones; EE. UU. es el país con mayor productividad; la palabra clave más frecuente es compulsive buying. Se identifican tres equipos de investigación principales del fenómeno y se elaboró un análisis de contenido de sus publicaciones. Se realizó un reporte de los artículos más citados de las bases. Se concluye que existe poca precisión investigativa sobre la compra compulsiva pese al incremento de productividad anual.

Abstract In the consumer society, desires are transformed into needs and this affects the emergence of compulsive buying and its negative effects on a personal and social level. For this reason, an analysis and synthesis effort is required on the existing scientific knowledge, which improves the understanding of the area. The objective is to analyze the development of scientific production on compulsive buying. The inclusion criteria were: individual empirical articles and reviews, covering up to the year 2020 and without language bias. The databases Web of Science, Scopus and PsycINFO were used. Through a bibliometric analysis -with PRISMA criteria- and using the EndNote X9 reference manager, 971 publications were located. The results indicate: an increase in productivity since 2005; English is the prevailing language of the publications; USA is the country with the highest productivity; the most frequent keyword is compulsive buying. Three main research teams on the phenomenon were identified and a content analysis of their publications was made. A report of the most cited articles of the databases was made. It is concluded that there is little investigative precision on compulsive buying despite the increase in annual productivity.

Actividades de descanso y dificultades para su realización en estudiantes de medicina de la Universidad del Cauca, Colombia, durante la pandemia por SARS-COV-2 / Rest activities and the difficulties for their performance in medical students at the Universidad del Cauca, Colombia, during the SARS-COV-2 pandemic

Introducción: un descanso adecuado determina el estado de ánimo y desempeño durante las actividades diarias, así como la salud mental y éxito académico de un estudiante de medicina, quien posee alta carga académica. Por esto, conocer qué actividades practican, así como las dificultades en las mismas orienta un abordaje que permita su adecuada ejecución. Objetivo: describir las actividades de descanso y las dificultades para su realización durante la jornada académica de los estudiantes de medicina de la universidad del Cauca en tiempos de pandemia por SARS-CoV-2. Materiales y métodos: estudio descriptivo, transversal realizado en 230 estudiantes de medicina de la Universidad del Cauca, seleccionados con un muestreo probabilístico bietápico a quienes se les aplicó una encuesta virtual de 108 preguntas que abordó aspectos sociodemográficos y cada uno de los componentes del descanso y estilos de vida. Resultados: el 99.1% de estudiantes practican actividades de ocio. El 29.5% de ellos realizan sesiones de relajación. La actividad física estuvo presente en un 63.3%. La mayor parte de las actividades aumentaron durante el confinamiento. Las principales dificultades para su ejecución fueron la falta de tiempo y espacios físicos adecuados. Conclusiones: las actividades de ocio fueron las más encontradas en esta población, este resultado contribuye a la búsqueda de planes de mejoramiento asociados al bienestar estudiantil. Hace falta evaluar el estrés y más aspectos sobre salud mental, nuevos estudios podrían enfocarse en este aspecto de suma importancia en estudiantes de medicina.

Summary Introduction: Adequate rest determines the mood and performance during daily activities, as well as the mental health and academic success of a medical student with a high academic load. Therefore, knowing what activities they engage in, as well as the difficulties to execute them, provides an approach that permits their accomplishment properly. Objective: To describe the rest activities and the difficul- ties in performing them during the academic day of medical students at the Universidad del Cauca in times of the SARS-CoV-2 pandemic. Materials and methods: A descriptive, cross-sectional study was conducted among 230 medical students of the Universidad del Cauca, selected with a two-stage probabilistic sampling, who were administered an online survey of 108 questions that addressed socio-demo- graphic aspects and each of the components of rest and lifestyles. Results: 99.1% of students undertake leisure activities. 29.5% of them do relaxation sessions. Physical exercise was present in 63.3%. Most of the activities increased during confinement. The main difficulties for their execution were the lack of time and adequate physical spaces. Conclusions: Leisure activities were the most frequently encountered in this population. Knowing the difficulties perceived by the students contributes to the exploration for improvement plans associated with student wellbeing. There is a need to assess stress and more aspects of mental health, new studies could focus on this aspect of utmost importance in medical students.

Cultural adaptation and validation of the COPCORD questionnaire for the detection of rheumatic diseases in the indigenous Misak population

Introduction: The objective was to adapt and valídate in a culturally sensitive way the methodology of the community-oriented programme for the control of rheumatic diseases (COPCORD) in the indigenous Misak community of Colombia. Material and methods: A culturally sensitive validation of the COPCORD questionnaire in Spanish was carried out, translating into the nam trik wam language used by the Misak community of Guambia town. It was adapted to the context of this population and later a back-translation to Spanish was carried out. Finally, it was validated applying the survey with the support of bilingual translators. Participants with pain, stiffness or swelling in any joint in the previous 7 days and/or at any time in life were evaluated by physicians and physiotherapists and were then, upon confirming the diagnosis of a musculoskeletal disorder, subsequently examined by a rheumatologist. Results: In this population (n = 106), 58.5% were women with an average age of 45.5 years. In the last 7 days, 51 subjects (48.1%) reported having musculoskeletal pain and 7 (44.3%) reported pain at some time in their life. Of those who received treatment, 53.1% reported using traditional medicine, 34.4% homeopathic treatment, and 25% allopathic treatment. The COPCORD Misak demonstrated an adequate capacity to detect musculoskeletal disorders, with a sensitivity of 63.3% and a specificity of 80.3%, with a positive likelihood ratio of 3.2, and area under the curve of.71. Conclusion: The COPCORD methodology is a valid screening tool to detect musculoskeletal disorders in the Misak community.

Introducción: El objetivo fue adaptar y validar, de forma culturalmente sensible, la metodología del Programa orientado a la comunidad para el control de enfermedades reumáticas (COPCORD) en la comunidad indígena misak de Colombia. Material y métodos: Se realizó una validación culturalmente sensible del cuestionario Copcord en español, que se tradujo al nam trik wam, lengua usada por el pueblo misak del resguardo de Guambia. El cuestionario se adecuó al contexto de esta población y posteriormente se llevó a cabo una retrotraducción al español. Por último, se validó aplicando la encuesta con el apoyo de traductores bilingües. Los participantes con dolor, rigidez o hinchazón en cualquier articulación en los siete días previos, o en cualquier momento de la vida, fueron evaluados por médicos y fisioterapeutas. Al confirmarse el diagnóstico de una enfermedad musculoesquelética los participantes eran examinados por un reumatólogo. Resultados: De la población estudiada (n = 106) el 58,5% fueron mujeres, con una edad promedio de 45,4 arios. En los últimos siete días, 51 sujetos (48,1%) informaron tener dolor musculoesquelético y siete (44,3%) refirieron dolor en algún momento de su vida. Quienes recibieron tratamiento reportaron el uso de medicamentos tradicionales en un 53,1% de los casos, homeopáticos en el 34,4% y alopáticos en el 25%. El cuestionario COPCORD Misak demostró una adecuada capacidad para detectar los trastornos musculoesqueléticos, con una sensibilidad del 63,3%, una especificidad del 80,3%, una razón de verosimilitud positiva de 3,2 y un área bajo la curva de 0,71. Conclusión: La metodología COPCORD es una herramienta válida de cribado de enfermedades musculoesqueléticas en el pueblo misak.

Antibacterial and Anti-Inflammatory Properties of ZnO Nanoparticles Synthesized by a Green Method Using Sargassum Extracts.

The present work shows the synthesis of ZnO nanoparticles through a green method, using sargassum extracts, which provide the reducing and stabilizing compounds. The conditions of the medium in which the reaction was carried out was evaluated, that is, magnetic stirring, ultrasound assisted, and resting condition. UV-Vis, FTIR spectroscopy, and X-ray diffraction results confirmed the synthesis of ZnO with nanometric crystal size. The scanning electron microscopy analysis showed that the morphology and size of the particles depends on the synthesis condition used. It obtained particles between 20 and 200 nm in the sample without agitation, while the samples with stirring and ultrasound were 80 nm and 100 nm, respectively. ZnO nanoparticles showed antibacterial activity against Gram-positive S. aureus and Gram-negative P. aeruginosa. A quantitative analysis was performed by varying the concentration of ZnO nanoparticles. In all cases, the antibacterial activity against Gram-positives was greater than against Gram-negatives. Ultrasound-assisted ZnO nanoparticles showed the highest activity, around 99% and 80% for S. aureus and P. aeruginosa, respectively. Similar results were obtained in the study of the anti-inflammatory activity of ZnO nanoparticles; the ultrasound-assisted sample exhibited the highest percentage (93%), even above that shown by diclofenac, which was used as a reference. Therefore, the ZnO nanoparticles synthesized with sargassum extracts have properties that can be used safely and efficiently in the field of biomedicine.

Molecular detection of Rickettsia felis in fleas and ticks collected from dogs and cats of Puebla, Mexico.

Fleas and ticks represent the two main groups of ectoparasites that infest companion animals. In particular, the flea Ctenocephalides felis felis and several members of the Rhipicephalus sanguineus complex are the main vectors of a wide range of pathogens on the American continent. They are competent vectors for several members of the genus Rickettsia, which encompass at least 15 pathogenic obligate intracellular bacteria that colonize the endothelial cells of vertebrates. In Mexico, 10 species of Rickettsia belonging to three groups have been detected in six species of ectoparasites from dogs in 9 of the 32 states of the country. However, in some larger regions of the country, active epidemiological surveillance has not been carried out. For this reason, the aim of this study was to identify the presence of members of the genus Rickettsia in fleas and ticks of dogs and cats in the state of Puebla, Mexico. A cross-sectional study was carried out to collect ectoparasites of dogs and cats during August to November 2019. Samples were fixed in 70% ethanol and examined to identify the presence of Rickettsia DNA by the amplification and sequencing of specific fragments of the gltA and ompB genes using conventional PCR. The recovered sequences were compared with those deposited in GenBank, and phylogenetic analyses were carried out to identify the position of the pathogens detected with respect to the valid species previously reported worldwide. Additionally, ecological parameters of the ectoparasite infestations were also calculated. We recovered 196 ectoparasites belonging to two species, 33 C. felis felis and 163 R. sanguineus s.l. (Rhipicephalus linnaei), parasitizing 46 hosts (42 dogs and 4 cats) in 11 localities of the state of Puebla. We detected the presence of Rickettsia felis in three pools of C. felis felis, and five from R. sanguineus s.l. Our work provides the first record of R. felis in hard ticks of Mexico and Central America, with new collection localities for this pathogen in central Mexico.

A story of a lone star tick: an imported case of Amblyomma americanum (Linnaeus, 1758) infected with Rickettsia amblyommatis that parasitized a US traveler returning to Mexico

ABSTRACT In this study, we report the presence of a female Amblyomma americanum tick attached to a former resident of the East Coast of the United States who moved to Mexico city. The amplification and sequencing of gene fragments of the 16S-rDNA and cytochrome c oxidase subunit 1 corroborated the identification of the species of the tick. Additionally, the presence of DNA of Rickettsia amblyommatis was confirmed. This work is the first report of an exotic tick of the genus Amblyomma in a traveler from the US to Mexico and represents the second record of an imported tick attached to humans in Mexico.

Enhancement of Heat and Mass Transfer in the DCMD Process Using UV-Assisted 1-Hexene-Grafted PP Membranes.

The two main challenges for industrial application of membrane distillation (MD) are mitigation of temperature polarization and reduction of high-energy consumption. Despite the development of advanced materials and the configuration improvements of MD units, membrane surface modification is still one of the alternatives to overcome temperature polarization and improve membrane performance. This work reports a novel and simple method to modify the physical and chemical properties of the polypropylene membrane in order to improve its performance in direct contact membrane distillation (DCMD). The membrane was grafted by polymerization with 1-hexene, UV irradiation, and benzophenone as a photoinitiator. A grafting degree of up to 41% was obtained under UV irradiation for 4 h. The performance of the modified membrane in DCMD was evaluated at different temperatures and salt concentrations in the feed. First, it was found that there was an increase of the vapor permeate flux in the MD process within the range of tested temperatures and salt concentrations. The results were analyzed in terms of the physical properties of the membrane, the transport phenomena, and the thermal efficiency of the process. Theoretical analysis of the results indicated that grafting increased the transfer coefficients of mass and heat of the membrane. Hence, it improved the membrane performance and the thermal efficiency of the DCMD process.

Is There a Place for Family-centered Cesarean Delivery during Placenta Accreta Spectrum Treatment? / Existe um lugar para cesariana centrada na família durante o tratamento do espectro da placenta acreta?

ABSTRACT Objective Placenta accreta spectrum (PAS) is a cause of massive obstetric hemorrhage and maternal mortality. The application of family-centered delivery techniques (FCDTs) during surgery to treat this disease is infrequent. We evaluate the implementation of FCDTs during PAS surgeries. Methods This was a prospective, descriptive study that included PAS patients undergoing surgical management over a 12-month period. The patients were divided according to whether FCDTs were applied (group 1) or not (group 2), and the clinical outcomes were measured. In addition, hospital anesthesiologists were surveyed to evaluate their opinions regarding the implementation of FCDTs during the surgical management of PAS. Results Thirteen patients with PAS were included. The implementation of FCDTs during birth was possible in 53.8% of the patients. The presence of a companion during surgery and skin-to-skin contact did not hinder interdisciplinary management in any case. Conclusion Implementation of FCDTs during PAS care is possible in selected patients at centers with experience in managing this disease.

Resumo Objetivo O espectro da placenta acreta (do inglês placenta accreta spectrum - PAS) é causa de hemorragia obstétrica maciça e mortalidade materna. A aplicação de técnicas de parto centrado na família (do inglês family-centered delivery techniques - FCDTs) durante a cirurgia para tratar esta doença é pouco frequente. Avaliamos a implementação das FCDTs durante as cirurgias do PAS. Métodos Estudo prospectivo e descritivo que incluiu pacientes com PAS submetidos a tratamento cirúrgico durante um período de 12 meses. Os pacientes foram divididos de acordo com a aplicação de FCDTs (grupo 1) ou não (grupo 2), e os resultados clínicos foram medidos. Além disso, anestesiologistas hospitalares foram entrevistados para avaliar suas opiniões sobre a implementação das FCDTs durante o manejo cirúrgico do PAS. Resultados Foram incluídos 13 pacientes com PAS. A implementação de FCDTs durante o parto foi possível em 53,8% das pacientes. A presença do acompanhante durante a cirurgia e o contato pele a pele não prejudicou o manejo interdisciplinar em nenhum caso. Conclusão A implementação de FCDTs durante o atendimento do PAS é possível em pacientes selecionados em centros com experiência no manejo dessa doença.

Primer registro de un caso de loxoscelismo cutáneo ocasionado por mordedura de araña violinista (Loxosceles yucatana) en Yucatán, México / First record of a case of cutaneous loxoscelism caused by violin spider (Loxosceles yucatana) bite in Yucatan, Mexico

El loxoscelismo es ocasionado cuando el veneno dermonecrótico producido por las arañas del género Loxosceles, conocidas como «arañas violinistas», ingresa al organismo de una persona a través de su mordida. En México ocurre un subregistro de los casos de loxoscelismo por la ausencia de pruebas de laboratorio para su diagnóstico y la dificultad del cuadro clínico. El objetivo de este trabajo es describir un caso de loxoscelismo cutáneo ocasionado por mordedura de Loxosceles yucatana en un residente de Yucatán, México. El loxoscelismo cutáneo es el tipo más frecuente y menos severo. El presente caso se diagnosticó por medio de la sintomatología registrada en la historia clínica, la lesión inicial y la identificación de arañas L. yucatana. Este trabajo representa la primera descripción de un caso de loxoscelismo cutáneo con resolución favorable en Yucatán.

Loxoscelism occurs when the dermonecrotic venom produced by spiders of the genus Loxosceles, known as "violin spiders," enters a person's organism through their bite. In Mexico there is an underreporting of loxoscelism cases due to the absence of laboratory tests for its diagnosis and the complexity of the clinical picture. The aim of this paper is to describe a case of cutaneous loxoscelism caused by the bite of Loxosceles yucatana in a resident of Yucatan, Mexico. Cutaneous loxoscelism is the most frequent and less severe type. This case was diagnosed by means of the symptomatology registered in the medical records, the initial lesion, and the identification of L. yucatana spiders. This study represents the first description of a case of cutaneous loxoscelism with favorable outcome in Yucatan.