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1.
Proc Natl Acad Sci U S A ; 121(30): e2320378121, 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-39008675

RESUMEN

The neuroscientific examination of music processing in audio-visual contexts offers a valuable framework to assess how auditory information influences the emotional encoding of visual information. Using fMRI during naturalistic film viewing, we investigated the neural mechanisms underlying the effect of music on valence inferences during mental state attribution. Thirty-eight participants watched the same short-film accompanied by systematically controlled consonant or dissonant music. Subjects were instructed to think about the main character's intentions. The results revealed that increasing levels of dissonance led to more negatively valenced inferences, displaying the profound emotional impact of musical dissonance. Crucially, at the neuroscientific level and despite music being the sole manipulation, dissonance evoked the response of the primary visual cortex (V1). Functional/effective connectivity analysis showed a stronger coupling between the auditory ventral stream (AVS) and V1 in response to tonal dissonance and demonstrated the modulation of early visual processing via top-down feedback inputs from the AVS to V1. These V1 signal changes indicate the influence of high-level contextual representations associated with tonal dissonance on early visual cortices, serving to facilitate the emotional interpretation of visual information. Our results highlight the significance of employing systematically controlled music, which can isolate emotional valence from the arousal dimension, to elucidate the brain's sound-to-meaning interface and its distributive crossmodal effects on early visual encoding during naturalistic film viewing.


Asunto(s)
Percepción Auditiva , Emociones , Imagen por Resonancia Magnética , Música , Percepción Visual , Humanos , Música/psicología , Femenino , Masculino , Adulto , Percepción Visual/fisiología , Percepción Auditiva/fisiología , Emociones/fisiología , Adulto Joven , Mapeo Encefálico , Estimulación Acústica , Corteza Visual/fisiología , Corteza Visual/diagnóstico por imagen , Corteza Visual Primaria/fisiología , Estimulación Luminosa/métodos
2.
Cureus ; 16(2): e55089, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38558691

RESUMEN

Background Infection with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can lead to prolonged symptoms post-recovery, commonly known as long-term coronavirus disease 2019 (COVID-19) or "long COVID." Neuropsychiatric consequences of long COVID include cognitive dysfunction and sleep disturbances, which significantly impair daily living. This study aimed to explore the impact of long COVID on cognitive performance and sleep quality in patients receiving outpatient care. Material and methods This study involved a random sample of 138 of 363 patients, corresponding to 38% of the cohort, who tested positive for SARS-CoV-2 via polymerase chain reaction (PCR) between May 2020 and April 2021. These unvaccinated, non-hospitalized individuals, predominantly exhibiting mild disease symptoms, were prospectively assessed 11 months post-positive PCR test. After informed consent, demographic data, memory, and concentration impairment levels were collected through interviews. Participants reporting cognitive symptoms underwent the Mini-Mental State Examination (MMSE), the Montreal Cognitive Assessment (MOCA), and the Pittsburgh Sleep Quality Index. Statistical analyses were conducted, including Student's t-test, Chi-square, Fisher's test, Kruskal-Wallis test, and Pearson correlation coefficient, with a significance threshold set at p<0.05. Results Of the 138 participants, 76 (55.1%) were female and 62 (44.9%) were male. The mean age was 45.9 years (± 13.0), with an average educational attainment of 10.4 years (± 3.7). Roughly 50% of the patients reported significant memory and concentration issues (p<0.001). Thirty-three participants underwent detailed cognitive assessments, revealing a 2:1 female-to-male ratio and a significantly higher prevalence of depression in female participants. Cognitive deficits were diagnosed in five (15.2%) participants via the MMSE and in 26 (78.8%) via the MOCA test, with notable deficits in visuospatial/executive functions, language repeat, and deferred recall (p<0.001). A lower educational level was correlated with higher cognitive deficits (p=0.03). Conclusion The study findings reveal that cognitive impairments, as a consequence of COVID-19, can persist up to 11 months post-infection. The MOCA test proved more effective in diagnosing these deficits and requires adjustments based on educational background. Sleep parameters remained largely unaffected in this cohort, likely attributed to the mild nature of the initial symptoms and the outpatient management of the disease.

3.
Nutr Hosp ; 41(1): 230-243, 2024 Feb 15.
Artículo en Español | MEDLINE | ID: mdl-38047415

RESUMEN

Introduction: Introduction: intermittent fasting plans propose to limit food intake during specific periods as nutritional therapeutic strategies to treat different metabolic conditions in various clinical entities. However, the heterogeneity between each context of intermittent fasting could generate different results in metabolic parameters. Objective: to evaluate the clinical application of intermittent fasting and to discern whether it offers advantages over other traditional strategies. Methods: structured questions were formulated (PICO), and the methodology followed the guidelines established by the PRISMA 2020 statement. The search was conducted in different databases (PubMed, Cochrane Library and Google Scholar). Results: we found 3,962 articles, of which 56 were finally included; 3,906 articles that did not directly or indirectly answer the structured questions were excluded. Conclusions: compared to conventional diets, the various AI schemes do not generate advantages or disadvantages in terms of weight loss and lipid profile, although in the alternate-day variant there are greater insulin reductions than those observed in the continuous energy restriction. The heterogeneity of the interventions, the populations studied, the comparators, the results, and the type of design make it impossible to extrapolate the effects found in all clinical scenarios and generalize the recommendations.


Introducción: Introducción: los esquemas de ayuno intermitente (AI) proponen limitar la ingestión de alimentos durante periodos específicos. Se han propuesto como estrategia dietoterapéutica para tratar distintas condiciones metabólicas en diversos padecimientos, sin embargo, la heterogeneidad entre cada contexto de ayuno intermitente pudiera generar diferentes resultados en parámetros metabólicos. Objetivo: evaluar la aplicación clínica del ayuno intermitente y discernir si ofrece ventajas sobre otras estrategias tradicionales. Métodos: se formularon preguntas estructuradas (PICO) y la metodología se apegó a las guías establecidas por la declaración PRISMA 2020. Se realizó una búsqueda de literatura científica en las plataformas de PubMed, Cochrane Library y Google Scholar. Resultados: se encontraron 3.962 artículos, de los cuales se incluyeron finalmente 56, eliminando 3.906 trabajos que no contestaban directa o indirectamente las preguntas estructuradas. Conclusiones: frente a las dietas convencionales, los diversos esquemas de AI no generan ventajas ni desventajas en cuanto a pérdida de peso o perfil lipídico, aunque en la variante a días alternos se producen mayores reducciones de insulina a las observadas en la restricción energética continua. La heterogeneidad de las intervenciones y poblaciones estudiadas, así como los comparadores, los desenlaces y el tipo de diseño imposibilitan extrapolar los efectos a todos los escenarios clínicos y generalizar las recomendaciones.


Asunto(s)
Restricción Calórica , Obesidad , Humanos , Restricción Calórica/métodos , Ayuno , Ayuno Intermitente , Dieta
4.
Virology ; 589: 109916, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37925791

RESUMEN

Cross-neutralizing aptamers targeting both HSV-1 and HSV-2 were developed by selecting against the ectodomains of glycoprotein D (gD) from both viruses in parallel as well as sequentially using the SELEX method. Since gD facilitates viral invasion, sterically blocking the host-receptor interaction prevents infection. Candidate aptamers were screened, and lead aptamers were identified that exhibited exceptional neutralizing activity against both viruses in vitro. The specificity of the aptamers was confirmed by comparing their activity to scrambled versions of themselves. Modifications of the lead compounds were tested to define critical motifs to guide development. Stability of the aptamers was increased using phosphorothioate backbone linkages, and 2' methoxy substitutions of terminal and key internal bases. Aptamers were applied in a guinea pig vaginal HSV-2 infection model and found to reduce both the viral load of infected animals and the severity of the resulting disease. These results suggest that cross-neutralizing aptamers can be developed into on-demand antiviral interventions effective against both HSV-1 and HSV-2.


Asunto(s)
Aptámeros de Nucleótidos , Herpesvirus Humano 1 , Femenino , Animales , Cobayas , Herpesvirus Humano 2/genética , Herpesvirus Humano 1/genética , Proteínas del Envoltorio Viral/genética , Anticuerpos Antivirales
5.
BMJ Open ; 13(11): e077322, 2023 11 06.
Artículo en Inglés | MEDLINE | ID: mdl-37931967

RESUMEN

INTRODUCTION: Nearly 30 000 Mexican women develop breast cancer annually, frequently presenting unmet supportive care needs. In high-income countries, incorporating electronic patient-reported outcomes (ePROs) into cancer care has demonstrated potential for increasing patient-centred care and reducing unmet needs. No such ePRO interventions have been implemented in Mexico. This paper presents the study protocol for designing and evaluating an ePRO digital health application combined with proactive follow-up by nurses. METHODS AND ANALYSIS: We designed a two-component intervention for women receiving breast cancer treatment: a responsive web application for monitoring ePROs and clinical algorithms guiding proactive follow-up by nurses. We will conduct a pilot test of the intervention with 50 patients with breast cancer for 6 weeks to assess feasibility and adjust the application. We will conduct a parallel arm randomised controlled trial assigning 205 patients each to intervention and control in one of Mexico's largest public oncology hospitals. The intervention will be provided for 6 months, with additional 3 months of post-intervention observation. The control group will receive usual healthcare and a list of breast cancer information sources. Women diagnosed with stages I, II or III breast cancer who initiate chemotherapy and/or radiotherapy will be invited to participate. The primary study outcome will be supportive care needs; secondary outcomes include global quality of life and breast symptoms. Information on the outcomes will be obtained through web-based self-administered questionnaires collected at baseline, 1, 3, 6 and 9 months. ETHICS AND DISSEMINATION: The National Research and Ethics Committees of the Mexican Institute of Social Security approved the study (R-2021-785-059). Participants will sign an informed consent form prior to their inclusion. Findings will be disseminated through a policy brief to the local authorities, a webinar for patients, publications in peer-reviewed journals and presentations at national and international conferences. TRIAL REGISTRATION NUMBER: NCT05925257.


Asunto(s)
Neoplasias de la Mama , Humanos , Femenino , Calidad de Vida , México , Estudios de Seguimiento , Atención a la Salud , Ensayos Clínicos Controlados Aleatorios como Asunto
6.
Angew Chem Int Ed Engl ; 62(51): e202314659, 2023 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-37934031

RESUMEN

We here report the organocatalytic and temperature-controlled depolymerization of biobased poly(limonene carbonate) providing access to its trans-configured cyclic carbonate as the major product. The base TBD (1,5,7-triazabicyclo[4.4.0]dec-5-ene) offers a unique opportunity to break down polycarbonates via end-group activation or main chain scission pathways as supported by various controls and computational analysis. These energetically competitive processes represent an unprecedented divergent approach to polycarbonate recycling. The trans limonene carbonate can be converted back to its polycarbonate via ring-opening polymerization using the same organocatalyst in the presence of an alcohol initiator, offering thus a potential circular and practical route for polycarbonate recycling.

7.
Antiviral Res ; 219: 105733, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37858763

RESUMEN

Herpes is a contagious life-long infection with persistently high incidence and prevalence, causing significant disease worldwide. Current therapies have efficacy against active HSV infections but no impact on the latent viral reservoir in neurons. Thus, despite treatment, disease recurs from latency and the infectious potential remains unaffected within patients. Here, efficacy of the helicase-primase inhibitor (HPI) IM-250 against chronic neuronal HSV infections utilizing two classic herpes in vivo latency/reactivation animal models (intravaginal guinea pig HSV-2 infection model and ocular mouse HSV-1 infection model) is presented. Intermittent therapy of infected animals with 4-7 cycles of IM-250 during latency silences subsequent recurrences analyzed up to 6 months. In contrast to common experience, our studies show that the latent reservoir is indeed accessible to antiviral therapy altering the latent viral reservoir such that reactivation frequency can be reduced significantly by prior IM-250 treatment. We provide evidence that antiviral treatment during HSV latency can reduce future reactivation from the latent reservoir, supporting a conceptual shift in the antiviral field, and reframing what is achievable with respect to therapy of latent neuronal HSV infections.


Asunto(s)
Herpes Simple , Herpesvirus Humano 1 , Humanos , Animales , Ratones , Cobayas , ADN Primasa , Latencia del Virus/fisiología , Herpes Simple/tratamiento farmacológico , Herpesvirus Humano 1/fisiología , Modelos Animales de Enfermedad , Antivirales/farmacología , Antivirales/uso terapéutico
8.
Medicina (Kaunas) ; 59(8)2023 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-37629742

RESUMEN

Background: Glycation products have been linked to decreased bone mineral density (BMD) in a number of clinical settings. This study examined the correlation between early glycation products (HbA1c and glycated albumin (ALB-g)) and advanced glycation end products (pentosidine (PTD)) with BMD in two groups of participants: those with type 2 diabetes mellitus (DM2) and those without diabetes or any other comorbidities (noDM). All of the participants had resided in southeastern Mexico for a minimum of 10 years. Material and Methods: This study included 204 participants: 112 (55%) with DM2 and 92 (45%) healthy subjects. We utilized dual X-ray absorptiometry (DXA) to measure both the total and segment-specific BMD and adipose mass. In addition, the fasting blood glucose, HbA1c, PTD, and ALB-g parameters were measured. Correlation and logistic regression analyses were conducted. Results: There was an inverse correlation between PTD and BMD in all anatomical regions among postmenopausal women (PMW) in the DM2 group, whereas in non-PMW, only the waist-to-height ratio was statistically significant. A negative correlation was observed between HbA1c levels and BMD in the arms and legs of DM2 individuals. However, in the noDM group, a negative correlation was found between HbA1c levels and BMD in the pelvis, while a positive association was observed between HbA1c and indicators of adipose tissue. ALB-g, demonstrated a negative correlation with fat mass. After performing binary logistic regressions, the following odds ratios (OR) for osteopenia/osteoporosis risk were determined: PTD OR 1.1 (p = 0.047) for DM2 PMW, HbA1c OR 1.4 (p = 0.048), and fat mass content OR 1.011 (p = 0.023) for the entire sample. Conclusions: Glycation products are associated with BMD differentially depending on the analyzed anatomical segment, but PTD, HbA1c, and fat mass are significant predictors of low bone mass. In prospective studies, this association could be determined using other techniques involving three-dimensional analysis of bone architecture to evaluate bone architecture.


Asunto(s)
Diabetes Mellitus Tipo 2 , Femenino , Humanos , Diabetes Mellitus Tipo 2/complicaciones , Densidad Ósea , Reacción de Maillard , Estudios Transversales , México/epidemiología , Hemoglobina Glucada , Estudios Prospectivos , Albúminas
9.
Sensors (Basel) ; 23(11)2023 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-37300066

RESUMEN

Eye blink artifacts in electroencephalographic (EEG) signals have been used in multiple applications as an effective method for human-computer interaction. Hence, an effective and low-cost blinking detection method would be an invaluable aid for the development of this technology. A configurable hardware algorithm, described using hardware description language, for eye blink detection based on EEG signals from a one-channel brain-computer interface (BCI) headset was developed and implemented, showing better performance in terms of effectiveness and detection time than manufacturer-provided software.


Asunto(s)
Parpadeo , Interfaces Cerebro-Computador , Humanos , Procesamiento de Señales Asistido por Computador , Electroencefalografía/métodos , Algoritmos , Computadores , Artefactos
10.
Macromol Rapid Commun ; 44(15): e2300132, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37191109

RESUMEN

Six acrylamide resins, derived from l-phenylalanine and l-leucine, are designed for application in digital light processing (DLP) printers to obtain biodegradable thermoset polymers. The acrylamide copolymers are prepared under light irradiation at 405 nm and thermal post-curing processes. Low molecular weight poly(ethylene glycol)diacrylate (PEGDA) and N,N-dimethylacrylamide (DMAM), both liquid resins, are used as co-monomers and diluents for the amino acid-derived acrylamide solubilization. The presence of two phenylalanine units and two ester groups in the acrylamide monomer accuses a fast degradation rate in hydrolytic medium in 90 days. The residual products leached in the aqueous media prove to be non-cytotoxic, when 3D-printed samples are cultured with osteoblast cells (MG63), which represents an advantage for the safe disposal of printer waste materials. The scaled-up pieces derived from l-phenylalanine and diethylene glycol, as amino acid-derived acrylamide (named compound C), PEGDA and DMAM, present high dimensional stability after DLP printing of complex structures used as testing samples. Layers of 50 µm of thickness are well cohesive having isotropic behavior, as demonstrated with tensile-strain measurements performed in X-Y-Z (plane) directions. The compound C, which contains phenylalanine amino acid, reveals a promising potential to replace non-biodegradable acrylate polymers used in prototyping systems.


Asunto(s)
Acrilamida , Aminoácidos , Impresión Tridimensional , Polímeros , Fenilalanina
11.
Viruses ; 14(11)2022 10 22.
Artículo en Inglés | MEDLINE | ID: mdl-36366414

RESUMEN

Herpes simplex virus 1 and 2 infections cause high unmet disease burdens worldwide. Mainly HSV-2 causes persistent sexually transmitted disease, fatal neonatal disease and increased transmission of HIV/AIDS. Thus, there is an urgent requirement to develop effective vaccines. We developed nucleic acid vaccines encoding a novel virus entry complex stabilising cell membrane fusion, 'virus-like membranes', VLM. Two dose intramuscular immunisations using DNA expression plasmids in a guinea pig model gave 100% protection against acute disease and significantly reduced virus replication after virus intravaginal challenge. There was also reduced establishment of latency within the dorsal root ganglia and spinal cord, but recurrent disease and recurrent virus shedding remained. To increase cellular immunity and protect against recurrent disease, cDNA encoding an inhibitor of chemokine receptors on T regulatory cells was added and compared to chemokine CCL5 effects. Immunisation including this novel human chemokine gene, newly defined splice variant from an endogenous virus genome, 'virokine immune therapeutic', VIT, protected most guinea pigs from recurrent disease and reduced recurrent virus shedding distinct from a gD protein vaccine similar to that previously evaluated in clinical trials. All DNA vaccines induced significant neutralising antibodies and warrant evaluation for new therapeutic treatments.


Asunto(s)
Herpes Genital , Vacunas de ADN , Recién Nacido , Cobayas , Humanos , Animales , Herpesvirus Humano 2/genética , Vacunas de ADN/genética , Internalización del Virus , Proteínas del Envoltorio Viral/genética , Inmunización , Quimiocinas , Modelos Animales de Enfermedad , Anticuerpos Antivirales
12.
Rev. méd. Chile ; 150(11): 1484-1492, nov. 2022. ilus, graf, tab
Artículo en Inglés | LILACS | ID: biblio-1442059

RESUMEN

BACKGROUND: COVID-19 patients may experience Long-lasting symptoms from weeks to even months. AIM: To evaluate long-term cognitive impairment based on the severity of symptoms of COVID-19 infection in a primary health system setting. Material and Methods: From a database of 363 patients, 83 cases aged 47 ± 15 years, (58% females) were selected from June to August 2020. In patients who survived the virus, 24 infection-related symptoms were collected to create three severity clusters (mild, moderate, and severe). The follow-up time was at least seven months. Comparing the first two clusters with the severe cluster, the existence of brain fog and risk factors (obesity, hypertension, diabetes, chronic lung disease, and hypothyroidism) were analyzed. RESULTS: Thirty-one patients (37%) had persistent symptoms lasting up to 240 days. Fifty-one patients (61%) experienced brain fog. Concentration was affected by symptom severity (odds ratio [OR] 3.63, 95% confidence interval [CI] 1.26-10.46, p = 0.02). Short- or long-term memory loss was not affected. Moreover, symptom severity was related to brain fog (OR 3.16, 95% CI 1.05-9.51, p = 0.04). Patients with persistent symptoms had a concentration impairment associated with severity patterns (OR 24.3, 95% CI 1.73-340.11, p = 0.03). Conclusions: Brain fog is associated with symptom severity in COVID-19 survivors and lasts for more than eight months.


ANTECEDENTES: Los pacientes que han tenido COVID-19 pueden experimentar síntomas persistentes que duran semanas a meses. OBJETIVO: Evaluar el deterioro cognitivo a largo plazo en función de la severidad de los síntomas de la infección por COVID-19, en un escenario de sistema primario de salud. Material y Métodos: De una base de datos de 363 pacientes se seleccionaron 83 casos de 47 ± 15 años (58% mujeres), de junio-agosto de 2020. Se recopilaron 24 síntomas relacionados con la infección, creando tres grupos (leve, moderado y severo), en pacientes que padecieron y sobreviven al virus. El tiempo de seguimiento fue de al menos siete meses. La existencia de niebla cerebral y de factores de riesgo (obesidad, hipertensión, diabetes, enfermedad pulmonar crónica e hipotiroidismo) se comparó los dos grupos de severidad más bajos con el nivel superior. RESULTADOS: Treinta y un pacientes (37%) tuvieron síntomas prolongados con una duración de hasta 240 días. Cincuenta y un pacientes (61%) mostraron niebla cerebral. El deterioro de la concentración fue afectado por la severidad (Razón de riesgo (RR) = 3,63, Intervalos de confianza (IC) 95%: 1,26-10,46, p = 0,02). La pérdida de memoria a corto o largo plazo no fue afectada. El grupo con mayor severidad se asoció a niebla cerebral (RR = 3,16, IC95%: 1,05-9,51, p = 0,04). Los portadores de síntomas prolongados tuvieron una alteración de la concentración asociado a severidad (RR: 3,16, IC95%: 1,05-9,51, p= 0,04). Conclusiones: La niebla cerebral está relacionada con la severidad de los síntomas en supervivientes de COVID-19 permaneciendo por más de ocho meses.


Asunto(s)
Humanos , Masculino , Femenino , Diabetes Mellitus , COVID-19 , Hipertensión , Encéfalo , Factores de Riesgo
13.
Vaccine ; 40(42): 6093-6099, 2022 10 06.
Artículo en Inglés | MEDLINE | ID: mdl-36114130

RESUMEN

Herpes simplex virus type 1 and 2 (HSV-1 and HSV-2 respectively) cause life-long latent infections resulting in recurrent orofacial and genital blisters or sores. Ensued disease can be painful and may lead to significant mental anguish of infected individuals. Currently, there are no FDA-approved vaccines for either prophylactic or therapeutic use, and recent clinical trials of subunit vaccines failed to achieve endpoints goals. Development of a safe live-attenuated herpes simplex vaccine may provide the antigenic breadth to ultimately protect individuals from acquiring HSV disease. We have previously shown that prophylactic use of the non-neurotropic live attenuated HSV-1 vaccine, VC-2, provides potent and durable protection from genital HSV-2 disease in the guinea pig model. Here, we investigated the effects of intradermal administration as well as the deletion of the viral glycoprotein G (gG) on the efficacy of prophylactic vaccination. Vaccination with either VC-2, VC-2 gG null, or gD2 MPL/Alum offered robust protection from acute disease regardless of route of vaccination. However, both the VC-2 gG-null and the ID vaccination route were more effective compared to the parent VC2 administered by the IM route. Specifically, the VC-2 gG-null administered ID, reduced HSV-2 vaginal replication on day 2 and day 4 as well as mean recurrent lesion scores more effectively than VC2 administered IM. Most importantly, only VC-2 gG null IM and VC-2 ID significantly reduced the frequency of recurrent shedding, the most likely source for virus transmission. Similarly, while all vaccinated groups demonstrated a significant reduction in the number of animals testing PCR-positive for HSV-2 in their dorsal root ganglia following challenge only VC2 ID vaccinated animals demonstrated a significant reduction in DRG viral load. All vaccinations induced neutralizing antibodies to HSV-2 MS when compared to unvaccinated guinea pigs. Therefore, further investigation of VC-2 gG null delivered ID is warranted.


Asunto(s)
Herpes Genital , Vacunas contra el Virus del Herpes Simple , Herpes Simple , Herpesvirus Humano 1 , Animales , Anticuerpos Neutralizantes , Anticuerpos Antivirales , Femenino , Glicoproteínas , Cobayas , Herpes Genital/prevención & control , Herpes Simple/prevención & control , Herpesvirus Humano 1/genética , Herpesvirus Humano 2/genética , Vacunación , Vacunas Atenuadas , Vacunas de Subunidad , Proteínas del Envoltorio Viral/genética
14.
ACS Sustain Chem Eng ; 10(8): 2708-2719, 2022 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-35360277

RESUMEN

In the area of coating development, it is extremely difficult to find a substitute for bisphenol A diglycidyl ether (DGEBA), the classical petroleum-based raw material used for the formulation of epoxy thermosets. This epoxy resin offers fast curing reaction with several hardeners and the best thermal and chemical resistance properties for applications in coatings and adhesive technologies. In this work, a new biobased epoxy, derived from poly(limonene carbonate) oxide (PLCO), was combined with polyetheramine and polyamineamide curing agents, offering a spectrum of thermal and mechanical properties, superior to DGEBA-based thermosets. The best formulation was found to be a combination of PLCO and a commercial curing agent (Jeffamine) in a stoichiometric 1:1 ratio. Although PLCO is a solid due to its high molecular weight, it was possible to create a two-component partially biobased epoxy paint without the need of volatile organic compounds (i.e., solvent-free formulation), intended for use in coating technology to partially replace DGEBA-based thermosets.

15.
Rev. Fac. Med. Hum ; 22(2): 252-257, Abril.- Jun. 2022.
Artículo en Inglés, Español | LILACS-Express | LILACS | ID: biblio-1371494

RESUMEN

Introducción: El melanoma es un problema de salud pública, representa 4% de los tumores malignos de la piel y es responsable de 80% de las muertes por este tipo de neoplasias. Objetivo: presentar la respuesta a Temozolomida en pacientes con melanoma metastásico. Métodos: Estudio descriptivo, transversal. Se analizó la respuesta clínica de pacientes con melanoma metastásico, manejados con Temozolomida 200 mg/m2 una vez al día, durante 5 días cada 28 días. Los factores de riesgo analizados fueron: variedad histológica, región topográfica de lesión primaria, metástasis, ulceración y Breslow. Se utilizó estadística descriptiva, para normalidad Kolmogorov-Smirnoff, t de Student, así como regresión logística binaria. Resultados: Fueron 51 expedientes, 47 cumplieron con los criterios; 25 hombres, 22 mujeres, edad media 54.45, mínima 22, máxima 85 años, Se obtuvo una respuesta completa en 3(6.3%), respuesta parcial 7(14.8%), enfermedad estable en 10(21%) y progresión de la enfermedad en 27(57.44%) pacientes. La presencia de ulceración se asocia a mayor índice de Breslow, y como resultado, mayor riesgo de progresión de la enfermedad. Conclusiones: Temozolomida como monoterapia es un tratamiento que presenta bajas tasas de respuesta completa y respuesta parcial, mostrando mejores resultados en pacientes con metástasis ganglionares.


Introduction.Melanoma is a public health problem; it represents 4% of malignant skin tumors and is responsible for 80% of deaths from this type of neoplasm. Objective: Show the response to Temozolomide in patients with metastatic melanoma. Methods: Descriptive, cross-sectional study. The clinical response of patients with metastatic melanoma, managed with Temozolomide 200 mg/m2 once a day was analyzed for 5 days every 28 days. The risk factors analyzed were: histological variety, topographic region of the primary lesion, metastasis, ulceration, and Breslow. Descriptive statistics were used for normality Kolmogorov-Smirnoff, Student's t-test, and binary logistic regression. Results: There were 51 les, 47 met the criteria; 25 men, 22 women, mean age 54.45, minimum 22, maximum 85 years, Complete response was obtained in 3 (6.3%), partial response in 7 (14.8%), stable disease in 10 (21%) and disease progression in 27 (57.44%) patients. The presence of ulceration is associated with a higher Breslow index and, as a result, a higher risk of disease progression. Conclusions: Temozolomide as monotherapy is a treatment that presents low rates of complete response and partial response, showing better results in patients with lymph node metastases.

16.
ChemSusChem ; 15(7): e202102624, 2022 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-35189036

RESUMEN

Biobased epoxy-derived raw materials will be essential for future coating and adhesive designs in industry. Here, a facile approach is reported towards the incorporation of limonene into an epoxy-functionalized polycarbonate and its crosslinking with a polyamine curing agent to obtain a thermoset material. For the first time, a solvent-borne adhesive with excellent film-forming, mechanical and adhesion strength properties is described.


Asunto(s)
Adhesivos , Resinas Epoxi , Plásticos , Solventes
17.
Rev Med Chil ; 150(11): 1484-1492, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37358174

RESUMEN

BACKGROUND: COVID-19 patients may experience Long-lasting symptoms from weeks to even months. AIM: To evaluate long-term cognitive impairment based on the severity of symptoms of COVID-19 infection in a primary health system setting. MATERIAL AND METHODS: From a database of 363 patients, 83 cases aged 47 ± 15 years, (58% females) were selected from June to August 2020. In patients who survived the virus, 24 infection-related symptoms were collected to create three severity clusters (mild, moderate, and severe). The follow-up time was at least seven months. Comparing the first two clusters with the severe cluster, the existence of brain fog and risk factors (obesity, hypertension, diabetes, chronic lung disease, and hypothyroidism) were analyzed. RESULTS: Thirty-one patients (37%) had persistent symptoms lasting up to 240 days. Fifty-one patients (61%) experienced brain fog. Concentration was affected by symptom severity (odds ratio [OR] 3.63, 95% confidence interval [CI] 1.26-10.46, p = 0.02). Short- or long-term memory loss was not affected. Moreover, symptom severity was related to brain fog (OR 3.16, 95% CI 1.05-9.51, p = 0.04). Patients with persistent symptoms had a concentration impairment associated with severity patterns (OR 24.3, 95% CI 1.73-340.11, p = 0.03). CONCLUSIONS: Brain fog is associated with symptom severity in COVID-19 survivors and lasts for more than eight months.


Asunto(s)
COVID-19 , Diabetes Mellitus , Hipertensión , Femenino , Humanos , Masculino , Factores de Riesgo , Encéfalo
18.
Comput Ind Eng ; 161: 107591, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34511709

RESUMEN

Governments have been challenged to provide timely medical care to face the COVID-19 pandemic. The aim of this research is to propose a novel inventory pooling model to help determine order sizes and safety inventories in local hospital warehouses. The current study attempts to portray the availability of pharmaceutical items in public hospitals facing COVID-19 challenges. Different from previous studies, this research builds upon the consecrated theory of inventory pooling, extending it to pandemic circumstances where the intractability of kurtosis and skewness in inventory models are critical issues for making sure that medicines have high availability at a low cost. These effects on the total cost of inventory are explored and compared to a supply system with no consolidation. A continuous-review model is assumed with allocation rules for centralization and regular transshipment given different skewness and kurtosis structures for the demand, describing them by the copula method. This method models a multivariate demand considering that the marginal distributions of the demand can be specified by the Generalized Additive Model for Location, Scale and Shape, which offers advantages to model demands considering virtually any marginal statistical distribution. Numerical simulations and an illustrative example show that distributions of demands with more negative skewness and high kurtosis favor to a greater extent obtaining lower total costs with regular supply transshipment systems. Our study points out important considerations for supply chain decision makers when having demands with skewness and kurtosis patterns.

19.
Org Lett ; 23(16): 6429-6434, 2021 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-34346687

RESUMEN

In the course of upscaling the synthesis of enantiopure aryliodine precatalysts, we detected an unreported meso form of the catalysts for the first time. A new scalable route was developed to avoid epimerization of the lactamide arms, providing syntheses of the precatalysts that are both more effective and much less time-consuming. The catalysts obtained with these synthetic procedures have been employed in some published reactions, reaching the maximum ee ever reported.

20.
Sensors (Basel) ; 21(16)2021 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-34450924

RESUMEN

(1) Goals: The purpose of this study was to analyze the feasibility of using the information obtained from a one-channel electro-encephalography (EEG) signal to control a mouse pointer. We used a low-cost headset, with one dry sensor placed at the FP1 position, to steer a mouse pointer and make selections through a combination of the user's attention level with the detection of voluntary blinks. There are two types of cursor movements: spinning and linear displacement. A sequence of blinks allows for switching between these movement types, while the attention level modulates the cursor's speed. The influence of the attention level on performance was studied. Additionally, Fitts' model and the evolution of the emotional states of participants, among other trajectory indicators, were analyzed. (2) Methods: Twenty participants distributed into two groups (Attention and No-Attention) performed three runs, on different days, in which 40 targets had to be reached and selected. Target positions and distances from the cursor's initial position were chosen, providing eight different indices of difficulty (IDs). A self-assessment manikin (SAM) test and a final survey provided information about the system's usability and the emotions of participants during the experiment. (3) Results: The performance was similar to some brain-computer interface (BCI) solutions found in the literature, with an averaged information transfer rate (ITR) of 7 bits/min. Concerning the cursor navigation, some trajectory indicators showed our proposed approach to be as good as common pointing devices, such as joysticks, trackballs, and so on. Only one of the 20 participants reported difficulty in managing the cursor and, according to the tests, most of them assessed the experience positively. Movement times and hit rates were significantly better for participants belonging to the attention group. (4) Conclusions: The proposed approach is a feasible low-cost solution to manage a mouse pointer.


Asunto(s)
Interfaces Cerebro-Computador , Atención , Electroencefalografía , Humanos , Movimiento
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