RESUMO
Asthma is a chronic immunological disease related to oxidative stress and chronic inflammation; both processes promote airway remodeling with collagen deposition and matrix thickening, causing pulmonary damage and lost function. This study investigates the immunomodulation of C-phycocyanin (CPC), a natural blue pigment purified from cyanobacteria, as a potential alternative treatment to prevent the remodeling process against asthma. We conducted experiments using ovalbumin (OVA) to induce asthma in Sprague Dawley rats. Animals were divided into five groups: (1) sham + vehicle, (2) sham + CPC, (3) asthma + vehicle, (4) asthma + CPC, and (5) asthma + methylprednisolone (MP). Our findings reveal that asthma promotes hypoxemia, leukocytosis, and pulmonary myeloperoxidase (MPO) activity by increasing lipid peroxidation, reactive oxygen and nitrogen species, inflammation associated with Th2 response, and airway remodeling in the lungs. CPC and MP treatment partially prevented these physiological processes with similar action on the biomarkers evaluated. In conclusion, CPC treatment enhanced the antioxidant defense system, thereby preventing oxidative stress and reducing airway inflammation by regulating pro-inflammatory and anti-inflammatory cytokines, consequently avoiding asthma-induced airway remodeling.
Assuntos
Remodelação das Vias Aéreas , Asma , Modelos Animais de Doenças , Ovalbumina , Estresse Oxidativo , Ficocianina , Ratos Sprague-Dawley , Animais , Ficocianina/farmacologia , Ficocianina/uso terapêutico , Asma/tratamento farmacológico , Asma/metabolismo , Asma/induzido quimicamente , Estresse Oxidativo/efeitos dos fármacos , Ovalbumina/efeitos adversos , Ratos , Remodelação das Vias Aéreas/efeitos dos fármacos , Inflamação/metabolismo , Inflamação/tratamento farmacológico , Masculino , Pulmão/efeitos dos fármacos , Pulmão/patologia , Pulmão/metabolismo , Citocinas/metabolismoRESUMO
Genomics has significantly revolutionized pathogen surveillance, particularly in epidemiological studies, the detection of drug-resistant strains, and disease control. Despite its potential, the representation of Latin American countries in the genomic catalogues of Mycobacterium tuberculosis (Mtb), the bacteria responsible for Tuberculosis (TB), remains limited. In this study, we present a whole genome sequencing (WGS)-based analysis of 85 Mtb clinical strains from 17 Mexican states, providing insights into local adaptations and drug resistance signatures in the region. Our results reveal that the Euro-American lineage (L4) accounts for 94% of our dataset, showing 4.1.2.1 (Haarlem, n = 32), and 4.1.1.3 (X-type, n = 34) sublineages as the most prevalent. We report the presence of the 4.1.1.3 sublineage, which is endemic to Mexico, in six additional locations beyond previous reports. Phenotypic drug resistance tests showed that 34 out of 85 Mtb samples were resistant, exhibiting a variety of resistance profiles to the first-line antibiotics tested. We observed high levels of discrepancy between phenotype and genotype associated with drug resistance in our dataset, including pyrazinamide-monoresistant Mtb strains lacking canonical variants of drug resistance. Expanding the Latin American Mtb genome databases will enhance our understanding of TB epidemiology and potentially provide new avenues for controlling the disease in the region.
Assuntos
Mycobacterium tuberculosis , Tuberculose Resistente a Múltiplos Medicamentos , Tuberculose , Humanos , Mycobacterium tuberculosis/genética , Antituberculosos/uso terapêutico , México/epidemiologia , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Tuberculose/tratamento farmacológico , Genótipo , Genômica , Testes de Sensibilidade Microbiana , Farmacorresistência Bacteriana Múltipla/genéticaRESUMO
The chemical composition of COVID test swabs has not been examined beyond the manufacturer's datasheets. The unprecedented demand for swabs to conduct rapid lateral flow tests and nucleic acid amplification tests led to mass production, including 3D printing platforms. Manufacturing impurities could be present in the swabs and, if so, could pose a risk to human health. We used scanning electron microscopy and energy dispersive X-ray (EDX) spectroscopy to examine the ultrastructure of seven assorted brands of COVID test swabs and to identify and quantify their chemical elements. We detected eight unexpected elements, including transition metals, such as titanium and zirconium, the metalloid silicon, as well as post-transition metals aluminium and gallium, and the non-metal elements sulphur and fluorine. Some of the elements were detected as trace amounts, but for others, the amount was close to reported toxicological thresholds for inhalation routes. Experimental studies have shown that the detrimental effects of unexpected chemical elements include moderate to severe inflammatory states in the exposed epithelium as well as proliferative changes. Given the massive testing still being used in the context of the COVID pandemic, we urge caution in continuing to recommend repeated and frequent testing, particularly of healthy, non-symptomatic, individuals.
RESUMO
This research study obtained the first morphological description of the Colorado snapper (Lutjanus colorado) larvae assisted by DNA barcoding as a molecular identification tool. Sixteen Lutjanidae larvae were separated from zooplankton samples and selected for this study. A fragment of the mitochondrial gene cytochrome oxidase subunit I (COI) of 658 bp was used in the analyses of intra- and interspecific genetic divergences; a neighbour-joining tree (NJ) of K2P distances was performed with reference sequences of 15 Lutjanidae species from the Northeastern Tropical Pacific. Genetic divergences and the NJ tree identified 16 larvae as L. colorado. Morphological investigations of larvae at different developmental stages were performed; similarities and differences are discussed in comparison to four species described previously for the Northeastern Pacific. Pigmentation patterns were the best diagnostic features, particularly the caudal melanophores, at least up to 12.4 mm body length.
Assuntos
Código de Barras de DNA Taxonômico , Perciformes , Animais , Larva/anatomia & histologia , Colorado , Complexo IV da Cadeia de Transporte de Elétrons/genética , Filogenia , Peixes/genética , Perciformes/genética , Perciformes/metabolismoRESUMO
Mental health disorders are relatively common in the general population and were already an important issue for the healthcare sector before COVID-19. COVID-19, being a worldwide crucial event and evidently a great stressor has increased both the prevalence and incidence of these. Therefore, it is evident that COVID-19 and mental health disorders are closely related. Moreover, several coping strategies exist to endure said disorders such as depression and anxiety, which are used by the population to confront stressors, and healthcare workers are not the exception. This was an analytical cross-sectional study, conducted from August to November 2022, via an online survey. Prevalence and severity of depression, anxiety, and stress were assessed via the DASS-21 test, and coping strategies were assessed via the CSSHW test. The sample consisted of 256 healthcare workers and of those, 133 (52%) were males with a mean age of 40.4 ± 10.35, and 123 (48%) were females with a mean age of 37.28 ± 9.33. Depression was prevalent in 43%, anxiety in 48%, and stress in 29.7%. Comorbidities were a significant risk factor for both depression and anxiety with an OR of 10.9 and 4.18, respectively. The psychiatric background was a risk factor for depression with an OR of 2.17, anxiety with an OR of 2.43, and stress with an OR of 3.58. The age difference was an important factor in the development of depression and anxiety. The maladaptive coping mechanism was prevalent in 90 subjects and was a risk factor for depression (OR of 2.94), anxiety (OR of 4.46) and stress (OR of 3.68). The resolution coping mechanism was a protective factor for depression (OR of 0.35), anxiety (OR of 0.22), and stress (OR of 0.52). This study shows that mental health disorders are highly prevalent among healthcare workers in Mexico and that coping strategies are associated with their prevalence. It also implies that not only occupations, age, and comorbidities might affect mental health, but also the way patients confront reality and the behavior and decisions they take towards stressors.
Assuntos
COVID-19 , Masculino , Feminino , Humanos , Adulto , Pessoa de Meia-Idade , COVID-19/epidemiologia , Estudos Transversais , Saúde Mental , Pandemias , México , SARS-CoV-2 , Depressão/epidemiologia , Estresse Psicológico/epidemiologia , Pessoal de Saúde/psicologia , Adaptação Psicológica , Ansiedade/epidemiologiaRESUMO
This study aimed to determine an optimal dosage of sunflower oil (i.e., Virgin Cooking Oil, VCO) as a rejuvenator for asphalt self-healing purposes, evaluating its effect on the chemical (carbonyl, and sulfoxide functional groups), physical (penetration, softening point, and viscosity), and rheological (dynamic shear modulus, and phase angle) properties of long-term aged (LTA) bitumen. Five concentrations of sunflower oil (VCO) were used: 1%, 2%, 3%, 4%, and 5% vol. of LTA bitumen. VCO was encapsulated in alginate biopolymer under vibrating jet technology using three biopolymer:oil (B:O) mass ratios: 1:1, 1:5, and 1:9. The physical, thermal, and mechanical properties of the capsules were studied, as well as their effect on the physical properties of dense asphalt mixtures. The main results showed that an optimal VCO content of 4% vol. restored the chemical, physical, and rheological properties of LTA bitumen to a short-term ageing (STA) level. VCO capsules with B:O ratios of 1:5 presented good thermal and mechanical stability, with high encapsulation efficiency. Depending on the B:O ratio, the VCO capsule dosage to rejuvenate LTA bitumen and asphalt mixtures varied between 5.03-15.3% wt. and 0.24-0.74% wt., respectively. Finally, the capsule morphology significantly influenced the bulk density of the asphalt mixtures.
RESUMO
Amaranth 11S globulins (Ah11Sn) are an excellent source of essential amino acids; however, there have been no investigations on the characterization of their techno-functional properties at different pH conditions and NaCl concentrations, which are necessary for food formulations. In this work, we report a new two-step purification method for native Ah11Sn with purity levels of ~95%. LC-MS/MS analysis revealed the presence of three different Ah11Sn paralogs named Ah11SB, A11SC, and Ah11SHMW, and their structures were predicted with Alphafold2. We carried out an experimental evaluation of Ah11Sn surface hydrophobicity, solubility, emulsifying properties, and assembly capacity to provide an alternative application of these proteins in food formulations. Ah11Sn showed good surface hydrophobicity, solubility, and emulsifying properties at pH values of 2 and 3. However, the emulsions became unstable at 60 min. The assembly capacity of Ah11Sn evaluated by DLS analysis showed mainly the trimeric assembly (~150-170 kDa). This information is beneficial to exploit and utilize Ah11Sn rationally in food systems.
RESUMO
OBJECTIVE: To determine the incidence of adverse reactions (AR) after the first dose of Pfizer-BioNTech vaccine, and to identify some factors associated with AR. METHOD: A retrospective cohort study was conducted. Data were obtained through an epidemiological survey answered online. Multivariate analyses were performed to identify factors associated with early (< 2 h) and late (≥ 2 h) AR. RESULTS: A total of 2295 health care workers were included; in them, the cumulative incidence of AR was 18.2% (95% confidence interval: 16.6-19.8), where the majority were late (78.2%). The associated factors that increased the risk of early AR were being female (odds ratio [OR]: 2.23, p = 0.002) and belonging to the medical staff (OR: 1.56; p = 0.041). In late AR were being female (OR: 1.94; p < 0.0001); on the other hand, diabetes (OR: 0.46; p = 0.021), asthma (OR: 0.53; p = 0.040) and smoking (OR: 0.44, p = 0.002) were inversely associated factors. Interestingly, history of COVID-19 was not associated with either early or late AR. CONCLUSIONS: The risk of presenting some type of AR due to the Pfizer-BioNTech vaccine in health care workers is < 20%.
OBJETIVO: Determinar la incidencia de reacciones adversas (RA) tras la primera dosis de la vacuna Pfizer-BioNTech e identificar algunos factores asociados con ellas. MÉTODO: Se realizó un estudio de cohorte retrospectiva. Los datos fueron obtenidos mediante una encuesta epidemiológica contestada en línea. Se realizaron análisis multivariados para identificar factores asociados con las RA tempranas (< 2 h) y tardías (≥ 2 h). RESULTADOS: Se incluyeron 2295 trabajadores de la salud; en ellos, la incidencia acumulada de RA fue del 18.2% (intervalo de confianza del 95%: 16.6-19.8%) y la mayoría fueron tardías (78.2%). Las RA tempranas más frecuentes fueron dolor local, cefalea y mareo; en las tardías fueron dolor local, cefalea y fatiga. No se documentaron casos de anafilaxia; sin embargo, en el grupo de RA tempranas y tardías hubo un caso y tres casos, respectivamente, con síntomas sistémicos que afectaron a dos órganos diferentes. Los factores asociados que incrementaron el riesgo de RA tempranas fueron ser mujer (odds ratio [OR]: 2.23; p = 0.002) y pertenecer al personal médico (OR: 1.56; p = 0.041). En las RA tardías fue ser mujer (OR: 1.94; p < 0.0001); por su parte, la diabetes (OR: 0.46; p = 0.021), el asma (OR: 0.53; p = 0.040) y el tabaquismo (OR: 0.44; p = 0.002) fueron factores asociados inversamente. Es interesante que la historia de COVID-19 no se asoció con RA tempranas ni tardías. CONCLUSIONES: El riesgo de presentar algún tipo de RA debido a la vacuna Pfizer-BioNTech en trabajadores de la salud es < 20%.
Assuntos
COVID-19 , Diabetes Mellitus , Humanos , Feminino , Masculino , Estudos Retrospectivos , COVID-19/epidemiologia , COVID-19/prevenção & controle , Fumar/efeitos adversos , Fumar/epidemiologia , IncidênciaRESUMO
BACKGROUND AND AIMS: Triglycerides are the initiators of the metabolic changes that lead to atherogenic dyslipidemia (AD). The APOA5 and APOA1 genes are involved in the response and metabolism of serum lipids and lipoproteins, where single nucleotide polymorphisms (SNP) rs662799 (promoter region) and rs5070 (intronic region) have been associated with the susceptibility to dyslipidemia. Until now, few studies evaluate the association of these polymorphisms with the presentation of hypertriglyceridemia and AD among Mexican children. Therefore, the objective was to determine the association between rs662799 and rs5070 with hypertriglyceridemia and AD in a pediatric population of southeastern Mexico. MATERIALS AND METHODS: A case-control analysis was performed including 268 infants aged 2-16 years, anthropometric, clinical variables, and serum lipid profiles were analyzed. DNA was extracted from blood samples and genotyping of polymorphisms was executed with the TaqMan SNP genotyping assay. Allele and genotypic frequencies were calculated. For genetic association analysis, logistic regression models were fitted according to models of inheritance. RESULTS: The SNP rs662799 (C) was significantly associated with hypertriglyceridemia in the overdominant model (OR=3.89, p=0.001) and AD in the dominant model (OR=4.01, p=0.001). The SNP rs5070 (T) has a protective effect against hypertriglyceridemia in the additive risk model (OR=0.68, p=0.03). CONCLUSION: Polymorphism rs662799 was significantly associated with cases of hypertriglyceridemia and AD in minors in southeastern Mexico. On the other hand, rs5070 polymorphism was not associated with cases of hypertriglyceridemia or AD.
Assuntos
Aterosclerose , Dislipidemias , Hipertrigliceridemia , Humanos , Criança , México , Apolipoproteína A-V/genética , Genótipo , Hipertrigliceridemia/genética , Polimorfismo de Nucleotídeo Único , Aterosclerose/genética , Dislipidemias/genética , Predisposição Genética para Doença , Frequência do Gene , TriglicerídeosRESUMO
This study evaluated the effect of two encapsulation methods (i.e., dropping funnel and syringe pump), two concentrations of the alginate-based encapsulating material (2%, and 3%), and three oils as bitumen rejuvenators (virgin sunflower oil, waste cooking oil, and virgin engine oil) on the morphological, physical, chemical, thermal, and mechanical properties of encapsulated rejuvenators for asphalt self-healing purposes. A general factorial design 2 × 2 × 3 was proposed to design 12 different Ca-alginate capsules. Significant differences on the morphological, physical, and mechanical properties of the capsules were analysed by three-way ANOVA and Tukey HSD Post Hoc analyses. The effect of the type of oil on the self-healing capacity of cracked bitumen samples was also evaluated. The main results showed that the design parameters and their interactions significantly affected the morphological, physical, and mechanical properties of the capsules. Capsules synthesised via syringe pump method, with virgin cooking oil and 2% alginate was the most appropriate for asphalt self-healing purposes since its uniform morphology, encapsulation efficiency up to 80%, thermal degradation below 5% wt., and compressive strength above the reference asphalt compaction load of 10 N. Finally, the healing tests showed that virgin cooking oil can be potentially used as a rejuvenator to promote asphalt crack-healing.
RESUMO
Legumes are an essential source of nutrients that complement energy and protein requirements in the human diet. They also contribute to the intake of bioactive compounds such as polyphenols, whose content can vary depending on cultivars and genotypes. We conducted a comparative proteomics and metabolomics study to determine if there were significant variations in relevant nutraceutical compounds in the five genotypes of Kabuli-type chickpea grains. We performed an isobaric tandem mass tag (TMT) couple to synchronous precursor selection (SPS)-MS3 method along with a targeted and untargeted metabolomics approach based on accurate mass spectrometry. We observed an association between the overproduction of proteins involved in starch, lipid, and amino acid metabolism with gibberellin accumulation in large grains. In contrast, we visualized the over-accumulation of proteins associated with water deprivation in small grains. It was possible to visualize in small grains the over-accumulation of some phenolics such as vanillin, salicylic acid, protocatechuic acid, 4-coumaric acid, 4-hydroxybenzoic acid, vanillic acid, ferulic acid, and kaempferol 3-O-glucoside as well as the amino acid l-phenylalanine. The activated phenolic pathway was associated with the higher antioxidant capacity of small grains. Small grains consumption could be advantageous due to their nutraceutical properties.
RESUMO
Background: Data on abortion procedures costs are scarce in low- and middle-income countries. In Mexico, the only known study was conducted more than a decade ago, with data from years before the abortion legislation. This study estimated the costs, from the health system's perspective, of surgical and medical abortion methods commonly used by women who undergo first-trimester abortion in Mexico. Methods: Data were collected on staff time, salaries, medications, consumables, equipment, imaging, and lab studies, at 5 public general hospitals. A bottom-up micro-costing approach was used. Results: Surgical abortion costs were US$201 for manual vacuum aspiration and US$298 for sharp curettage. The cost of medical abortion with misoprostol was US$85. The use of cervical ripening increases the costs by up to 18%. Staff comprised up to 72% of total costs in surgical abortions. Hospitalization was the area where most of the spending occurred, due to the staff and post-surgical surveillance required. Conclusions: Our estimates reflect the costs of "real-life" implementation and highlight the impact on costs of the overuse of resources not routinely recommended by clinical guidelines, such as cervical ripening for surgical abortion. This information will help decision-makers to generate policies that contribute to more efficient use of resources.
RESUMO
Nitrate/nitrite-dependent anaerobic oxidation of methane (N-AOM) is a metabolic process recently discovered and partially characterized in terms of the microorganisms and pathways involved. The N-AOM process can be a powerful tool for mitigating the impacts of greenhouse gas emissions from wastewater treatment plants by coupling the reduction of nitrate or nitrite with the oxidation of residual dissolved methane. Besides specific anaerobic methanotrophs such as bacteria members of the phylum NC10 and archaea belonging to the lineage ANME-2d, recent reports suggested that other methane-oxidizing bacteria in syntrophy with denitrifiers can also perform the N-AOM process, which facilitates the application of this metabolic process for the oxidation of residual methane under realistic scenarios. This work constitutes a state-of-art review that includes the fundamentals of the N-AOM process, new information on process microbiology, bioreactor configurations, and operating conditions for process implementation in WWTP. Potential advantages of the N-AOM process over aerobic methanotrophic biotechnologies are presented, including the potential interrelation of the N-AOM with other nitrogen removal processes within the WWTP, such as the anaerobic ammonium oxidation. This work also addressed the challenges of this biotechnology towards its application at full scale, identifying and discussing critical research niches.
Assuntos
Gases de Efeito Estufa , Purificação da Água , Anaerobiose , Archaea/metabolismo , Reatores Biológicos , Gases de Efeito Estufa/metabolismo , Metano/metabolismo , Nitratos/metabolismo , Nitritos , OxirreduçãoRESUMO
Proteomics is an essential tool to uncover the regulatory processes of fruit biology. In fruits with high proteolytic activity, the inhibition of endogenous proteases is key for successful protein extraction. In this chapter, we describe an efficient protocol for total protein extraction to deal with this inconvenience using pineapple pulp as an example. We corroborated the efficacy of our protein extraction protocols by carrying out nano LC-MS/MS analyses using a highly sensitive hybrid mass spectrometer. In doing so, we were able to identify over 3000 proteins in pineapple pulp. Our contribution paves the way for massive comparative proteomics scrutiny in pineapple fruits, as well as others plant tissues with high protease activity such as papaya, fig, and kiwi fruits.
Assuntos
Ananas , Proteômica , Frutas/metabolismo , Peptídeo Hidrolases , Proteínas de Plantas/metabolismo , Proteômica/métodos , Espectrometria de Massas em TandemRESUMO
Reportes actuales sugieren que el antecedente de infección por SARS - CoV-2 y completar un esquema de vacunación otorga mayor protección contra la presentación sintomática de COVID -19. Se comparó el riesgo de enfermar de COVID -19 entre el personal de salud con esquema completo de vacuna contra SARS - CoV-2 BNT162b2 y el antecedente de infección por SARS - CoV-2. Estudio de cohorte histórica en 1874 trabajadores de la salud del Nuevo Hospital Civil de Guadalajara inmunizados con la vacuna BNT162b2 entre enero y marzo de 2021. Después de seis meses de seguimiento, el grupo de no expuestos (sin antecedente de infección) fue de 1397 y el grupo expuesto (con antecedente de infección), de 477 sujetos. La incidencia de infección por SARS - CoV-2 fue de 39 casos. El riesgo de infección en la cohorte posterior a la inmunización fue de 0,021. El grupo de inmunización híbrida presentó un riesgo menor de infección comparado con el grupo de inmunización artificial (0,015 y 0,243). La inmunización híbrida contribuyó a una reducción del riesgo atribuible a la población de 0,003 (R0 0,024; Rp 0,020). La hospitalización se presentó en el 7,69 % de los casos confirmados con SARS - CoV-2. El riesgo de hospitalización en inmunización híbrida es de 0,210 y de 0,143 en el grupo de inmunización artificial (RR 1,46 IC95 % 0,13 -16,11). Se llegó a la conclusión que la inmunización híbrida podría contribuir a reducir el riesgo de infección por SARS - CoV-2, potenciando la inmunidad generada por la vacuna contra COVID -19
Current reports suggest that a history of SARS - CoV-2 infection and completing a vaccination schedule provides greater protection against the symptomatic presentation of COVID -19. The risk of becoming ill with COVID -19 was compared between health personnel with a complete SARS - CoV-2 BNT162b2 vaccine schedule and a history of SARS - CoV-2 infection. Historical cohort study in 1874 health workers of the New Civil Hospital of Guadalajara immunized with the BNT162b2 vaccine between January and March 2021. After six months of follow-up, the non-exposed group (without a history of infection) was 1397 and the exposed group (with a history of infection), of 477 subjects. The incidence of SARS - CoV-2 infection was 39 cases. The risk of infection in the post-immunization cohort was 0.021. The hybrid immunization group had a lower risk of infection compared to the artificial immunization group (0.015 and 0.243). Hybrid immunization contributed to a population-attributable risk reduction of 0.003 (R0 0.024, Rp 0.020). Hospitalization occurred in 7.69% of confirmed cases with SARS - CoV-2. The risk of hospitalization in hybrid immunization is 0.210 and 0.143 in the artificial immunization group (RR 1.46 CI95% 0.13 -16.11). It was concluded that hybrid immunization could help reduce the risk of SARS - CoV-2 infection, enhancing the immunity generated by the vaccine against COVID -19
Assuntos
Imunização , Pessoal de Saúde , Síndrome Respiratória Aguda Grave , El Salvador , Vacina BNT162 , InfecçõesRESUMO
In this study, we analyzed the sequences of SARS-CoV-2 isolates of the Delta variant in Mexico, which has completely replaced other previously circulating variants in the country due to its transmission advantage. Among all the Delta sublineages that were detected, 81.5 % were classified as AY.20, AY.26, and AY.100. According to publicly available data, these only reached a world prevalence of less than 1%, suggesting a possible Mexican origin. The signature mutations of these sublineages are described herein, and phylogenetic analyses and haplotype networks are used to track their spread across the country. Other frequently detected sublineages include AY.3, AY.62, AY.103, and AY.113. Over time, the main sublineages showed different geographical distributions, with AY.20 predominant in Central Mexico, AY.26 in the North, and AY.100 in the Northwest and South/Southeast. This work describes the circulation, from May to November 2021, of the primary sublineages of the Delta variant associated with the third wave of the COVID-19 pandemic in Mexico and highlights the importance of SARS-CoV-2 genomic surveillance for the timely identification of emerging variants that may impact public health.
Assuntos
COVID-19 , SARS-CoV-2 , COVID-19/epidemiologia , Humanos , México/epidemiologia , Pandemias , Filogenia , SARS-CoV-2/genéticaRESUMO
Asphalt pavements and bituminous composites are majorly damaged by bitumen aging and fatigue cracking by traffic load. To add, maintenance and reparation of asphalt pavements is expensive and also releases significant amounts of greenhouse gases. These issues can be mitigated by promoting asphalt self-healing mechanisms with encapsulated rejuvenators. The ability of the required microcapsules to be resilient against high temperatures, oxidation, and mechanical stress is essential to promote such self-healing behavior without compromising the field performance of the asphalt pavement. This work proposes, for the first time, the use of extremely resistant biobased spores for the encapsulation of recycled oil-based rejuvenators to produce more resilient self-healing pavements. Spore encapsulants were obtained from natural spores (Lycopodium clavatum) by applying different chemical treatments, which enabled the selection of the best morphologically intact and clean spore encapsulant. The physical, morphological, and physicochemical changes were examined using fluorescence images, ATR-FTIR, SEM, size distribution, XRD, TGA and DSC analyses. Sunflower oil was used as the encapsulated rejuvenator with an optimal sol colloidal mixture for sporopollenin-oil of 1:5 (gram-to-gram). Vacuum, passive, and centrifugal encapsulation techniques were tested for loading the rejuvenator inside the clean spores and for selecting the best encapsulation technology. The encapsulation efficiency and the profiles of the accelerated release of the rejuvenator from the loaded spores over time were studied, and these processes were visualized with optical and inverted fluorescence microscopy. Vacuum encapsulation was identified as the best loading technique with an encapsulation efficiency of 93.02 ± 3.71%. The rejuvenator was successfully encapsulated into the clean spores, as observed by optical and SEM morphologies. In agreement with the TGA and DSC, the microcapsules were stable up to 204 °C. Finally, a self-healing test was conducted through fluorescence tests to demonstrate how these biobased spore microcapsules completely heal a crack into an aged bitumen sample in 50 min.
RESUMO
ABSTRACT Background: Asthma does not appear to be a risk factor for developing COVID-19. Objective: The objective of the study was to analyze the role of asthma as a factor associated with COVID-19 among healthcare workers (HW). Methods: A cross-sectional study was conducted in HW from a Mexican hospital. Data were obtained through an epidemiological survey that included age, sex, and history of COVID-19. Multivariate logistic regression analysis was performed to identify factors associated with COVID-19. Results: In total, 2295 HW were included (63.1% women; mean age 39.1 years); and 1550 (67.5%) were medical personnel. The prevalence of asthma in HW with COVID-19 was 8.3%; for the group without COVID-19, the prevalence was 5.3% (p = 0.011). The multivariate analyses suggested that asthma was associated with COVID-19 (OR 1.59, p = 0.007). Conclusion: Our study suggests that asthma could be a factor associated with COVID-19 in HW.