In Vitro Antimycotic Activity and Structural Damage against Canine Malassezia pachydermatis Strains Caused by Mexican Stingless Bee Propolis.

This work describes the antimycotic activity of propolis from the stingless bees Scaptotrigona mexicana and Tetragonisca angustula, collected from two Mexican regions (Veracruz and Chiapas, respectively), against three clinical isolates and the reference strain ATCC 14522 of Malassezia pachydermatis, the causative agent of canine otitis. The chemical components of the ethanolic extracts of propolis were determined by gas chromatography coupled with mass spectrometry (GC-MS), and sesquiterpenes were the predominant compounds. The antimycotic activity was evaluated by plate microdilution. The induced changes in the yeasts were evaluated by fluorescence microscopy and staining with calcofluor white and propidium iodide. The minimum inhibitory concentration (MIC) was 7.11 mg/mL, and the minimum fungicidal concentration was 21.33 mg/mL for both extracts. The EPPs of Scaptotrigona mexicana and Tetragonisca angustula caused substantial damage to yeast morphology, where the propidium iodide staining of the yeasts treated with both EEPs revealed the penetration of this marker, which indicates the destruction of the cell wall and plasma membrane of the fungi. This result suggests that these types of propolis could be used as alternative treatments for canine external otitis. To the best of our knowledge, this seems to be the first scientific report that has demonstrated structural damage in Malassezia pachydermatis by Mexican stingless bee propolis.

Factors associated with mental health in Peruvian medical students during the COVID-19 pandemic: a multicentre quantitative study.

OBJECTIVE: To assess the mental health status and associated factors of Peruvian medical students during the COVID-19 pandemic. METHODS: Descriptive, multicentre, correlational study that used the "Patient Health Questionnaire-9 (PHQ-9)", the "Generalized Anxiety Disorder-7 (GAD-7)" and the "Impact of Event Scale-Revised (IES-R)" questionnaires to evaluate mental health problems. RESULTS: A total of 1,238 students from 8 Peruvian medical schools participated in the study. Of these, 68.5% were women, and the mean age was 21.4 years. Depressive symptoms were found in 74% of the participants, anxiety symptoms in 57% and distress symptoms in 65%. The variables associated with the development of symptoms of moderate-severe depression, anxiety and distress were: not having family economic stability, being in the first years of medical training, being female, and fearing that their medical training would be delayed and impaired. CONCLUSIONS: In a sample of medical students surveyed during the COVID-19 pandemic, mental health problems were common. The factors associated with mental health reported in this study could be useful in identifying vulnerable medical students who require timely psychosocial support and/or psychiatric care.

Multivariate Prognostic Models for Patients with Stages I and Ii Colon Carcinoma: a Strobe-Compliant Retrospective Cohort Study.

Background: Colorectal cancer is the most frequent gastrointestinal malignancy worldwide. The value of adjuvant treatment is controversial in Stages I and II. Objective: The aim of this study was to construct post-operative prognostic models applicable to patients with stages I-II colon carcinoma (CC). Methods: This is a retrospective cohort study of patients with Stage I-II CC treated over a 25-year period. Exposure was defined as clinical, histopathological, and immunohistochemical factors (including CDX2 and MUC2 expression). Patients were randomly allocated to either a "modeling set" or a "validation set". Factors associated with recurrence, disease-free survival (DFS), and overall survival (OS) were defined in the "modeling set". Their performances were tested in the "validation set". Results: From a total of 556 recruited patients, 339 (61%) were allocated to the "modeling set" and 217 (39%) to the "validation set". Three models explaining recurrence, DFS, and OS were described. Tumor location in the left colon (Hazards ratio [HR] = 1.57; 95% Confidence interval [CI] 0.99-2.48), lymphocyte (HR = 0.46; 96% CI 0.27-0.88) and monocyte (HR = 0.99; 95% CI 0.99-1) counts, neutrophil/platelet ratio (HR = 1.3; 95% CI 0.74-2.3, and HR = 2.3; 95% CI 1.3-4.1; for second and third category, respectively), albumin/monocyte ratio (HR = 0.43; 95% CI 0.21-0.87), and microscopic residual disease after surgery (HR = 8.7; 95% CI 3.1-24) were independently associated with OS. T classification and expression of CDX2 and/or MUC2 were not independently associated with recurrence or prognosis. Conclusion: These models are simple and readily available, and distinguish the risk and prognosis in patients with CC stages I and II; these models require cheaper processes than the use of more sophisticated molecular biology techniques. They may guide either the need for adjuvant therapy versus post-operative surveillance only, as well as aid in the design of clinical trials.

Multivariate Prognostic Models for Patients with Stages I and Ii Colon Carcinoma: a Strobe-Compliant Retrospective Cohort Study

ABSTRACT Background: Colorectal cancer is the most frequent gastrointestinal malignancy worldwide. The value of adjuvant treatment is controversial in Stages I and II. Objective: The aim of this study was to construct post-operative prognostic models applicable to patients with stages I-II colon carcinoma (CC). Methods: This is a retrospective cohort study of patients with Stage I-II CC treated over a 25-year period. Exposure was defined as clinical, histopathological, and immunohistochemical factors (including CDX2 and MUC2 expression). Patients were randomly allocated to either a "modeling set" or a "validation set". Factors associated with recurrence, disease-free survival (DFS), and overall survival (OS) were defined in the "modeling set". Their performances were tested in the "validation set". Results: From a total of 556 recruited patients, 339 (61%) were allocated to the "modeling set" and 217 (39%) to the "validation set". Three models explaining recurrence, DFS, and OS were described. Tumor location in the left colon (Hazards ratio [HR] = 1.57; 95% Confidence interval [CI] 0.99-2.48), lymphocyte (HR = 0.46; 96% CI 0.27-0.88) and monocyte (HR = 0.99; 95% CI 0.99-1) counts, neutrophil/platelet ratio (HR = 1.3; 95% CI 0.74-2.3, and HR = 2.3; 95% CI 1.3-4.1; for second and third category, respectively), albumin/monocyte ratio (HR = 0.43; 95% CI 0.21-0.87), and microscopic residual disease after surgery (HR = 8.7; 95% CI 3.1-24) were independently associated with OS. T classification and expression of CDX2 and/or MUC2 were not independently associated with recurrence or prognosis. Conclusion: These models are simple and readily available, and distinguish the risk and prognosis in patients with CC stages I and II; these models require cheaper processes than the use of more sophisticated molecular biology techniques. They may guide either the need for adjuvant therapy versus post-operative surveillance only, as well as aid in the design of clinical trials.

Aneurisma del seno de Valsalva roto a la aurícula derecha resuelto con intervencionismo / Rupture of sinus of Valsalva aneurysm to the right atrium resolved with interventionism

Resumen Se presenta un caso de aneurisma del seno de Valsalva derecho roto a la aurícula derecha, que en el transcurso de tres meses desarrolló insuficiencia cardiaca global y fue resuelto del todo por medio de intervencionismo, colocando un dispositivo oclusor en el sitio de la fístula. Se discute su etología, así como las pautas para el diagnóstico clínico y el tratamiento.

Abstract We present a case of a ruptured right sinus of Valsalva aneurysm to the right atrium that developed global heart failure over the course of three months, and which was completely resolved through cardiac catheterism, placing an occlusive device at the site of the fistula. Its ethology is discussed, as well as the guidelines for clinical diagnosis and treatment.

Rupture of sinus of Valsalva aneurysm to the right atrium resolved with interventionism.

We present a case of a ruptured right sinus of Valsalva aneurysm to the right atrium that developed global heart failure over the course of three months, and which was completely resolved through cardiac catheterism, placing an occlusive device at the site of the fistula. Its ethology is discussed, as well as the guidelines for clinical diagnosis and treatment.

Se presenta un caso de aneurisma del seno de Valsalva derecho roto a la aurícula derecha, que en el transcurso de tres meses desarrolló insuficiencia cardiaca global y fue resuelto del todo por medio de intervencionismo, colocando un dispositivo oclusor en el sitio de la fístula. Se discute su etología, así como las pautas para el diagnóstico clínico y el tratamiento.

Ballistic Behavior of Bioinspired Nacre-like Composites.

In this paper, the ballistic performance of a multilayered composite inspired by the structural characteristics of nacre is numerically investigated using finite element (FE) simulations. Nacre is a natural composite material found in the shells of some marine mollusks, which has remarkable toughness due to its hierarchical layered structure. The bioinspired nacre-like composites investigated here were made of five wavy aluminum alloy 7075-T651 (AA7075) layers composed of ~1.1-mm thick square tablets bonded together with toughened epoxy resin. Two composite configurations with continuous layers (either wavy or flat) were also studied. The ballistic performance of the composite plates was compared to that of a bulk monolithic AA7075 plate. The ballistic impact was simulated in the 300-600 m/s range using two types of spherical projectiles, i.e., rigid and elastoplastic. The results showed that the nacre plate exhibited improved ballistic performance compared to the bulk plate and the plates with continuous layers. The structural design of the nacre plate improved the ballistic performance by producing a more ductile failure and enabling localized energy absorption via the plastic deformation of the tablets and the globalized energy dissipation due to interface debonding and friction. All the plate configurations exhibited a better ballistic performance when impacted by an elastoplastic projectile compared to a rigid one, which is explained by the projectile plastic deformation absorbing some of the impact energy and the enlarged contact area between the projectile and the plates producing more energy absorption by the plates.

Functionalized Metal Nanoparticles in Cancer Therapy.

Currently, there are many studies on the application of nanotechnology in therapy. Metallic nanoparticles are promising nanomaterials in cancer therapy; however, functionalization of these nanoparticles with biomolecules has become relevant as their effect on cancer cells is considerably increased by photothermal and photodynamic therapies, drug nanocarriers, and specificity by antibodies, resulting in new therapies that are more specific against different types of cancer. This review describes studies on the effect of functionalized palladium, gold, silver and platinum nanoparticles in the treatment of cancer, these nanoparticles themselves show an anticancer effect. This effect is further enhanced when the NPs are functionalized with either antibodies, DNA, RNA, peptides, proteins, or folic acid and other molecules. These NPs can penetrate the cell and accumulate in the tumor tissue, resulting in a cytotoxic effect through the generation of ROS, the induction of apoptosis, cell cycle arrest, DNA fragmentation, and a photothermal effect. NP-based therapy is a new strategy that can be used synergistically with chemotherapy and radiotherapy to achieve more effective therapies and reduce side effects.

Factors associated with suicidal ideation among medical students during the initial phase of the COVID-19 pandemic in Peru: A multicenter study.

We aimed to describe the prevalence and factors associated with suicidal ideation in a sample of 1238 medical students from different medical schools in Peru based on question 9 of the Patient Health Questionnaire (PHQ-9). Our results revealed that 17.9% of the participants had suicidal ideation. Furthermore, using logistic regression, we found that not practicing any religion, the presence of clinically significant depression, and the presence of clinically significant anxiety were statistically related to the presence of suicidal ideation. Our results indicate that suicidal ideation was highly prevalent in the sample of medical students studied.

Use of ivermectin and factors associated with the prevention and/or treatment of COVID-19: a cross-sectional online survey in the province of Chincha, Peru.

Background: Peru has reported one of the highest mortality rates from COVID-19 worldwide. The Chincha province has been one of the most affected regions in Peru and the leading promoter of the use of ivermectin for the treatment of COVID-19. Therefore, our study aimed to evaluate the frequency of use and factors associated with the use of ivermectin for COVID-19 in Chincha. Methods: A cross-sectional study was conducted during the second wave of COVID-19 in Peru. For statistical analyses, frequencies and percentages were reported. Prevalence ratios (PR) with a 95% confidence interval (CI), and a p-value of 0.05 were used to determine statistical significance. SPSS version 22 (IBM Corp) program was used for the analyses. Results: A total of 432 participants were included in the study. A total of 67.6% (n = 292) of the participants used ivermectin during the COVID-19 pandemic. Of these, 20.20% (n=59) of the people used ivermectin for prophylactic purposes only, while 41.79% (n=122) used it as treatment for COVID-19 only, and 38.01% (n=111) used it for both reasons. The consumption of ivermectin was associated with being 50 years or older (PR:1.27, 95% CI:1.04-1.54), having a technical education level (PR:1.16, 95% CI:1.01-1.34), having had symptoms of COVID-19 with negative/no diagnosis (PR: 1.28, 95% CI: 1.07-1.53) or positive diagnosis (PR:1.38, 95% CI:1.18-1.61), or having had contact with infected people (PR:1.45, 95% CI:1.06-1.98). Conclusions: Most people in Chincha used ivermectin during the second wave of the COVID-19 pandemic. The main factors associated with the use of ivermectin for the prevention/treatment of COVID-19 were age ≥50 years, having a technical education level, having had symptoms with negative/no diagnosis or positive diagnosis, and contact with people infected with SARS-CoV-2.

Role of Micronutrients and Gut Microbiota-Derived Metabolites in COVID-19 Recovery.

A balanced and varied diet provides diverse beneficial effects on health, such as adequate micronutrient availability and a gut microbiome in homeostasis. Besides their participation in biochemical processes as cofactors and coenzymes, vitamins and minerals have an immunoregulatory function; meanwhile, gut microbiota and its metabolites coordinate directly and indirectly the cell response through the interaction with the host receptors. Malnourishment is a crucial risk factor for several pathologies, and its involvement during the Coronavirus Disease 2019 pandemic has been reported. This pandemic has caused a significant decline in the worldwide population, especially those with chronic diseases, reduced physical activity, and elder age. Diet and gut microbiota composition are probable causes for this susceptibility, and its supplementation can play a role in reestablishing microbial homeostasis and improving immunity response against Coronavirus Disease 2019 infection and recovery. This study reviews the role of micronutrients and microbiomes in the risk of infection, the severity of disease, and the Coronavirus Disease 2019 sequelae.

Tensile Behavior of 3D Printed Polylactic Acid (PLA) Based Composites Reinforced with Natural Fiber.

Natural fiber-reinforced composite (NFRC) filaments for 3D printing were fabricated using polylactic acid (PLA) reinforced with 1-5 wt% henequen flour comprising particles with sizes between 90-250 µm. The flour was obtained from natural henequen fibers. NFRCs and pristine PLA specimens were printed with a 0° raster angle for tension tests. The results showed that the NFRCs' measured density, porosity, and degree of crystallinity increased with flour content. The tensile tests showed that the NFRC Young's modulus was lower than that of the printed pristine PLA. For 1 wt% flour content, the NFRCs' maximum stress and strain to failure were higher than those of the printed PLA, which was attributed to the henequen fibers acting as reinforcement and delaying crack growth. However, for 2 wt% and higher flour contents, the NFRCs' maximum stress was lower than that of the printed PLA. Microscopic characterization after testing showed an increase in voids and defects, with the increase in flour content attributed to particle agglomeration. For 1 wt% flour content, the NFRCs were also printed with raster angles of ±45° and 90° for comparison; the highest tensile properties were obtained with a 0° raster angle. Finally, adding 3 wt% content of maleic anhydride to the NFRC with 1 wt% flour content slightly increased the maximum stress. The results presented herein warrant further research to fully understand the mechanical properties of printed NFRCs made of PLA reinforced with natural henequen fibers.

LKB-1 Expression and High-Risk Histopathology are Independent Prognostic Factors for Patients with Oral Cavity Carcinoma.

BACKGROUND: The expression of liver kinase B1 (LKB-1) has been associated with prognosis in squamous cell carcinoma of the oral cavity (SCCOC). This study aimed to define the prognostic role of LKB-1 expression for patients with SCCOC and the suitability of its integration into a multivariate prognostic model. METHODS: A retrospective cohort study of patients with SCCOC was conducted in a cancer center. Expression of LKB-1 was evaluated by immunohistochemistry, and multivariate analysis defined prognostic factors associated with recurrence, recurrence-free survival (RFS), and overall survival (OS). The logistic regression model was used to construct a predictive computer software program. RESULTS: Of the 201 patients in this study, 104 (51.7%) experienced recurrence of their disease. Lower expression of LKB-1, high-risk histopathology, and advanced tumor-node-metastasis (TNM) stages were independent factors via multivariate analysis associated with the increased recurrence risk, poor RFS, and poor OS. If lack of LKB-1 expression is considered the reference category, the factors independently associated with recurrence were low (odds ratio [OR], 0.157; 95% confidence interval [CI], 0.044-0.557), intermediate (OR, 0.073; 95% CI, 0.017-0.319), and intense (OR, 0.047; 95% CI, 0.007-0.304) expression of LKB-1. This model permitted construction of a computer software program capable of prediction with receiver operating characteristic analysis (area under the curve, 0.925) and led to the definition of five prognostic groups with a biologic gradient. CONCLUSION: These results suggest that LKB-1 expression in patients with SCCOC is of robust prognostic value and complements the TNM staging system. The proposed model requires external validation in prospective observational studies.

Psychometric properties of the Spanish version of the fear of COVID-19 scale in Peruvian medical students.

The Coronavirus Disease 2019 (COVID-19) pandemic continues to produce significant emotional consequences at the individual, community, societal, and global levels. This study describes the psychometric properties of the Spanish version of the Fear of COVID-19 Scale (FCV-19S) in Peruvian medical students. Data were collected by a convenience sampling method, resulting in a total of 1238 medical students from different medical schools in Peru. Our analyses suggest that a two-factor model explains the underlying two-dimensional structure of the FCV-19S. The results indicated that the Spanish version of the FCV-19S scale was found to have adequate psychometric properties.

Sobrevida de un paciente adulto mayor con cáncer de pulmón, tratado con quimioterapia de primera línea

RESUMEN Introducción: El cáncer de pulmón está afectando cada vez más a la población de adultos mayores, a medida que la expectativa de vida aumenta. Sin embargo, es difícil establecer la eficacia de la quimioterapia y el pronóstico de estos pacientes es grave. Objetivo: Presentar un caso de paciente adulto mayor con cáncer de pulmón avanzado de células no pequeñas, con una prolongada sobrevida que recibió solamente quimioterapia de primera línea. Caso clínico: Paciente no fumador, de 71 años, diagnosticado con cáncer de pulmón de células no pequeñas avanzado, del subtipo adenocarcinoma, con compromiso pleural. Inició tratamiento con carboplatino 5 AUC y gemcitabina 1,1 g. En el noveno ciclo, se encontró reducción de los nódulos pulmonares, pero también metástasis en el nivel D6-D7. Inició la segunda línea de tratamiento con carboplatino 5,4 AUC, paclitaxel 200 mg y ácido zolendrónico en dosis de 4,0 mg. Debido a eventos adversos, el tratamiento fue cambiado a vinorelbina 2,5 g y ácido zolendrónico 4,0 mg. Tras dos ciclos, el paciente fallece, alcanzando 21 meses de sobrevida global, solo con quimioterapia. Conclusión: El tratamiento del paciente adulto mayor con cáncer de pulmón es complejo. En el presente esquema de quimioterapia, el paciente pudo alcanzar 21 meses de sobrevida global, a pesar de que no fue caracterizado molecularmente.

ABSTRACT Introduction: Lung cancer is taking an increasing toll on the older population as life expectancy increases. However, the efficacy of chemotherapy is difficult to establish and the prognosis of these patients is severe. Objective: Report a case of an older adult patient with advanced non-small cell lung cancer with prolonged survival who received only first-line chemotherapy. Case report: A 71-year-old non-smoker patient diagnosed with advanced non-small cell lung cancer, adenocarcinoma subtype, with pleural involvement. He started treatment with carboplatin 5 AUC and gemcitabine 1,1 g. In the ninth cycle, reduction of pulmonary nodules was found, but he also had metastases at the D6-D7 level. He started the second line of treatment with carboplatin 5,4 AUC, paclitaxel 200 mg and zolendronic acid at a dose of 4,0 mg. Due to adverse events, the treatment was changed to vinorelbine 2,5 g and zolendronic acid 4.0 mg. After two cycles, the patient died, reaching 21 months of overall survival, only with chemotherapy. Conclusion: The treatment of the older adult patient with lung cancer is challenging. In the present chemotherapy treatment, the patient was able to achieve 21 months of overall survival, despite the fact that he was not molecularly characterized.