Polypropylene Graft Poly(methyl methacrylate) Graft Poly(N-vinylimidazole) as a Smart Material for pH-Controlled Drug Delivery.

Surface modification of polypropylene (PP) films was achieved using gamma-irradiation-induced grafting to provide an adequate surface capable of carrying glycopeptide antibiotics. The copolymer was obtained following a versatile two-step route; pristine PP was exposed to gamma rays and grafted with methyl methacrylate (MMA), and afterward, the film was grafted with N-vinylimidazole (NVI) by simultaneous irradiation. Characterization included Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), and physicochemical analysis of swelling and contact angle. The new material (PP-g-MMA)-g-NVI was loaded with vancomycin to quantify the release by UV-vis spectrophotometry at different pH. The surface of (PP-g-MMA)-g-NVI exhibited pH-responsiveness and moderate hydrophilicity, which are suitable properties for controlled drug release.

Development of a Physiological Age-Grading System for Nezara viridula (Hemiptera: Pentatomidae).

The southern green stink bug (SGSB), Nezara viridula (L.), is an important agricultural pest in the United States. Limited information is available on the morphology of the female's reproductive system in relation to morphological changes associated with the number of eggs produced and egg masses oviposited. The ability to assess reproductive health and reproductive status based on ovarian morphology (i.e., physiological age-grading) can be an important tool for evaluating field populations and laboratory colonies intended for the application of different management strategies and experimental trials. Thus, the goal of this study was to develop a physiological age-grading system for SGSB. Females aged from 0 to 79 d chronologically randomly selected from laboratory colonies and dissected to assess ovarian morphology. Specific morphological differences in ovarian structures including differentiation of the ovarioles, deposition of yolk in the most proximal follicle, quantity and appearance of follicular relics, expansion of the lateral oviducts, and number of developing follicles per ovariole were related to chronological age, the number of eggs produced and number of egg masses. Based on specific combinations of these morphological characteristics, the continuum of ovarian development was divided into three nulliparous (i.e., 'no eggs'; N1, N2, and N3) and three parous stages (i.e., 'with eggs'; P1, P2, and P3). Direct relationships were noted between number of eggs produced and physiological age with over 7-fold higher number of eggs and 14-fold higher number of egg masses associated with the P2 and P3 stages, respectively.

Lignocellulosic Membranes Grafted with N-Vinylcaprolactam Using Radiation Chemistry: Load and Release Capacity of Vancomycin.

Radiation chemistry presents a unique avenue for developing innovative polymeric materials with desirable properties, eliminating the need for chemical initiators, which can be potentially detrimental, especially in sensitive sectors like medicine. In this investigation, we employed a radiation-induced graft polymerization process with N-vinylcaprolactam (NVCL) to modify lignocellulosic membranes derived from Agave salmiana, commonly known as maguey. The membranes underwent thorough characterization employing diverse techniques, including contact angle measurement, degree of swelling, scanning electron microscopy (SEM), atomic force microscopy (AFM), Fourier-transform infrared-attenuated total reflectance spectroscopy (FTIR-ATR), nuclear magnetic resonance (CP-MAS 13C-NMR), X-ray photoelectron spectroscopy (XPS), and uniaxial tensile mechanical tests. The membranes' ability to load and release an antimicrobial glycopeptide drug was assessed, revealing significant enhancements in both drug loading and sustained release. The grafting of PNVCL contributed to prolonged sustained release by decreasing the drug release rate at temperatures above the LCST. The release profiles were analyzed using the Higuchi, Peppas-Sahlin, and Korsmeyer-Peppas models, suggesting a Fickian transport mechanism as indicated by the Korsmeyer-Peppas model.

Crosslinked Chitosan Films Supplemented with Randia sp. Fruit Extract.

This work proposes the development of a polymer film made up of affordable components for its use as a healthcare material. Chitosan, itaconic acid, and Randia capitata fruit extract (Mexican variation) are the unique ingredients of this biomaterial prospect. Chitosan (from crustacean chitin) is crosslinked with itaconic acid, and in situ added R. capitata fruit extract in a one-pot reaction carried out in water as the sole solvent. Structurally, the film formed is an ionically crosslinked composite characterized by IR spectroscopy and thermal analysis (DSC and TGA); cell viability was also performed in vitro using fibroblasts BALB/3T3. Dry and swollen films were analyzed to determine affinity and stability in water. This chitosan-based hydrogel is designed as a wound dressing due to the combined properties of the chitosan with R. capitata fruit extract, which has potential as bioactive material due to its properties in epithelial regeneration.

Silver Nanoparticles Loaded on Polyethylene Terephthalate Films Grafted with Chitosan.

Currently, polyethylene terephthalate (PET) is one of the most widely used polymeric materials in different sectors such as medicine, engineering, and food, among others, due to its benefits, including biocompatibility, mechanical resistance, and tolerance to chemicals and/or abrasion. However, despite all these excellent characteristics, it is not capable of preventing the proliferation of microorganisms on its surface. Therefore, providing this property to PET remains a difficult challenge. Fortunately, different strategies can be applied to remove microorganisms from the PET surface. In this work, the surface of the PET film was functionalized with amino groups and later with a dicarboxylic acid, allowing a grafting reaction with chitosan chains. Finally, the chitosan coating was loaded with silver nanoparticles with an average size of 130 ± 37 nm, presenting these materials with an average cell viability of 80%. The characterization of these new PET-based materials showed considerable changes in surface morphology as well as increased surface hydrophilicity without significantly affecting their mechanical properties. In general, the implemented method can open an alternative pathway to design new PET-based materials due to its good cell viability with possible bacteriostatic activity due to the biocidal properties of silver nanoparticles and chitosan.

Gamma rays: An alternative energy source for the preparation of manganese carbonyls-based new materials.

We report on the synthesis of new manganese carbonyls-based materials prepared using gamma-rays radiation (at doses of 10 and 40 kGy) as energy source. Characterization was achieved using nuclear magnetic resonance, infrared spectroscopy, elemental analysis, single-crystal X-ray diffraction, differential scan calorimetry, thermogravimetric analysis, and mass spectrometry. The irradiated materials presented enhanced thermal stability along with formation of spherical shaped microparticles sized around 0.95 µm attested by scanning electron microscopy and energy-dispersive X-ray spectroscopy.

Fostering Strategies to Expand the Consumption of Edible Insects: The Value of a Tripartite Coalition between Academia, Industry, and Government.

Although many insect-based foods are nutritious and often an inexpensive option for human and domesticated animal consumption, there remains a negligible market for such foods in many countries. Several environmental and economic considerations underscore the potential value of insect-based foods, and emerging science suggests that diets incorporating such foods might also convey some genuine health benefits. However, if expanded markets for insect-based foods in cultures naïve to entomophagy are to be pursued, it will be important to develop multifaceted and coordinated strategies to 1) delineate authentic health benefits, 2) explore means of optimizing insect husbandry and food processing, 3) examine cultural barriers to acceptance, 4) formulate workable approaches to marketing, and 5) address relevant food regulations. We sought to construct a multidisciplinary coalition whose goals are to investigate the above-mentioned 5 issues. Eighteen individuals from government, industry, and academia, with collective expertise in the fields of entomology, insect husbandry, human nutrition, sustainable agriculture, entomophagy, consumer product development and marketing, food-processing technologies, food regulatory affairs, and the anthropology of food selection, convened a 1-d summit and formed a tripartite organization to integrate their varied perspectives. Collaborative efforts are underway among members of this coalition to accomplish these multiple goals. Coordinating efforts between accomplished experts in relevant fields of academia, government, and industry will greatly expand our knowledge of and appreciation for the potential benefits of insect-based foodstuffs to individuals, to society, and to the sustainability of the global food supply, and thereby inform us as to how to proceed in a judicious and intelligent manner.

Seroepidemiology of Toxoplasma Gondii Infection in People Applying for Medical Certificates.

Medical certificates are documents that state the health status of a person. This study aimed to determine the seroprevalence and risk factors for Toxoplasma gondii infection in applicants of medical certificates and to investigate seroprevalence association with characteristics of these individuals. We examined 404 applicants in a public health center in Durango City, Mexico for the presence of anti-Toxoplasma IgG and IgM antibodies using enzyme-linked immunoassays. Of the 404 subjects (mean age of 35.94 ± 13.01) studied, 29 (7.2%) were positive for anti-T. gondii IgG antibodies and 9 (31.0%) of them were also positive for anti-T. gondii IgM antibodies. IgG and IgM seropositivities were associated with vision impairment (P = 0.04) and a history of surgery (P = 0.03), respectively. Prevalence of high (>150 IU/ml) IgG antibody levels was associated with hearing impairment (P = 0.03), and histories of lymphadenopathy (P = 0.04) and miscarriages (P = 0.03). Multivariate analysis showed that T. gondii seropositivity was associated with being born out of Durango State (odds ratio [OR] = 4.65; 95% confidence interval [CI]: 1.25-17. 29; P = 0.02) and soil contact (OR = 4.27; 95% CI: 1.71-10.67; P = 0.002) and negatively associated with consumption of sheep meat (OR = 0.12; 95% CI: 0.02-0.65; P = 0.01). These results could be used for the design of optimal preventive measures against toxoplasmosis and its sequelae.

Indicadores biológicos en los procesos de esterilización / Biological indicators in sterilization process

El objetivo de este estudio fue determinar la frecuencia del uso de indicadores biológicos de esterilidad en las Centrales de Equipos y Esterilización de los Hospitales de Oncología, Pediatría y Especialidades del Centro Médico Nacional Siglo XXI. El diseño fue una serie de casos. Fueron incluidos todos los procesos de purificación en esterilizadores de vapor o gas óxido de etileno, durante un periodo de seis meses. Las variables analizadas fueron el número de cargas, tipo de esterilización e indicador utilizado. El promedio diario de cargas de esterilización en el Hospital de Oncología fue de 7.72, en Pediatría 10.92 y en Especialidades 8.26. La esterilización por vapor es el método más utilizado (más de 90%). El uso de los indicadores biológicos fue bajo a pesar de que ofrecen doble factor de seguridad para verificar la eficacia del proceso: 32% en Pediatría, 4% en Especialidades y 3% en Oncología.

The objectives were to assess the amount, type and sterility indicators in the sterilization process. Design: series of cases. Study site: Central Equipment and Sterilization Service at the Oncology, Pediatrics and Specialties Hospitals of the 21st Century National Medical Center Mexican Institute of Social Security (IMSS), Mexico City, Mexico. Material and methods: all sterilization processes, whether vapor of ethylene oxide gas sterilizes were studied during a six-month period from three hospitals at the National Medical Center. Variables analyzed: number of loads, sterilize processes and indicator of sterility used. Results: the daily average sterilization loads were: Oncology 7.72, Pediatrics 10.92, Specialties 8.26. The vapor sterilize method was the type most frequently used (>90%). The percentage of utilization of the biological indicators of sterility showed: 32% pediatrics, 4% specialties and oncology 3%. Conclusions: in spite of the fact that the sterilization indicators are twice as safe, they are underused.

Lesiones endoteliales en quemaduras corneales / Endothelial injuries in corneal burnings

Las quemaduras corneales pueden presentarse por varios agentes químicos tanto ácidos como alcalinos o por agentes térmicos, las lesiones microscópicas se pueden valorar por los signos clínicos y la clasificiación de Huges-Roper-Hall, pero las lesiones microscópicas de los tejidos, en especial del endotelio corneal, no son valorables por este medio, por lo que la microscopía especular sería muy útil en estos casos. Se incluyeron a todos los pacientes con quemaduras unioculares, se les realizó microscopía especular en ambos ojos y se relacionó el grado de quemadura con las alteraciones endoteliales encontradas. Los cambios celulares encontrados fueron disminución de la densidad celular que es directamente proporcional a la disminución del porcentaje de hexagonalidad y esto a su vez presentó un agrandamiento celular y espacios intercelulares amplios

Técnicas anestésicas utilizadas para la cirugía de pacientes con cáncer de colon y/o recto / Anesthetic techniques for colon and rectum cancer patients

Antecedentes: En el hospital de oncología del CMN S XXI, los carcinomas de estómago, colon y recta son las neoplasias más frecuentes del tubo digestivo. Su tratamiento es quirúrgico, por tanto requieren manejo anestésico. Objetivo: analizar la experiencia sobre las técnicas anestésicas utilizadas en una población con cáncer colorrectal. Material y métodos: Serie de casos, 380 expedientes revisados para conocer las variables generales de la población y de la técnica anestésica utilizada. Resultados: 201 hombres y 179 mujeres, con una edad promedio de 56-59 años. El RAQ (ASA) fue I=19, II=10, III=147, IV=4, los niveles preoperatorios de proteínas plasmáticas, hemoglobina y hematocrito fueron normales. La mediana de la hemorragia intraoperatoria fue de 300 ml (rango 50-3500). El tiempo anestésico fue de 271.25 ñ 116.40 (rango 55-388). Las técnicas anestésicas fueron: anestesia general 357, espinal 16 y combinada en 7 pacientes. Conclusiones: En la cirugía por cáncer colorrectal la técnica anestésica más utilizada fue la anestesia general balanceada por el tiempo quirúrgico y la extensión del procedimiento quirúrgico

Laceración del canalículo lagrimal: experiencia de la Fundación Hospital "Nuestra Señora de la Luz" 1988-1998 / Canicular laceration: experience in the Fundación Hospital \"Nuestra Señora de la Luz\". 1988-1998

Para conocer la casuística de lesiones canaliculares en la Fundación Hospital "Nuestra Señora de la Luz" en los últimos 10 años, y determinar el tiempo adecuado de permanencia del implante, se realizó una investigación retrospectiva y descriptiva en la que se seleccionaron 93 expedientes que incluían diagnóstico de lesión canalicular. Sesenta y tres pacientes fueron sometidos a dacriointubación bicanalicular; se utilizó la modalidad anular en 10 casos y la nasal en 53 con tubo de silicona. La extracción del tubo se documentó en 41 casos, 30 programadas y 11 accidentales. El 60 por ciento de los casos de herida palpebral se han acompañado de lesión canalicular, y su manejo es similar al reportado en la literatura actual, obteniendo buenos resultados. El tubo puede permanecer por 6 meses o más dependiendo de la evolución, y su retiro a partir de las 6 semanas.

Evaluación experimental de un inmunógeno de Pasteurella heamolytica en corderos / Experimental evaluation of Pasteurella haemolytica immunogen in lambs

Se evaluó el efecto de la inoculación de cordero con bacterias vivas y citotoxina de Pasteurella heamolytica al desafío. Se utilizaron 40 corderos distribuidos al azar en 4 grupos. l grupo 1 (lote testigo) se le inoculò, por vía subcutánea, sólo medio de cultivo; el grupo 2 fue inmunizado con cultivo vivo de P. Haemolyticaserotipo Al por vía subcutánea; el grupo 3 recibío el mismo inmunógeno por vía intradérmica y el grupo 4 con citotoxina de P. Heamolytica por vía subcutanea más adyuvante completo de Freund. Los animales fueron expuestos al virus de P13 y desafiados una semana después con una cepa de P. Heamolytica Al. fueron sacrificados para la evaluación del daño pulmonar. Los animales del grupo testigo mostraron fiebre después del desafío bacteriano. Los títulos de anticuerpos anticápsula y antitotoxina fueron más altos para los grupos inmunizados. comparados con el grupo testigo (P < 0.05). Las lesiones en pulmón fueron más severas para el grupo testigo (P < 0.05), sin diferncia significativa entre las diversas vías de inmunización. Según los resultados obtenidos, se puede considerar que la protección conferida por la inmunización con P. heamolytica así como con citotoxina, es eficiente para reducir en forma considerable las lesiones pulmonares ocacionadas por esta bacteria experimentalmente. Asimismo, se demostró la inocuidad de los inmunogenos por ausencia de reacciones posvacunales.

Carcinoma colorectal, incidencia transfusional transanestésica / Colorectal carcinoma: transanesthetic incidence of transfusions

El objetivo del presente trabajo fue determinar la incidencia transfusional transanestésica en pacientes oncológicos con carcinoma colorrectal sometidos a cirugía resectiva. Diseño: Serie de casos. Lugar: Departamento de Anestesiología Hospital de Oncología, CMN siglo XXI, IMSS. México, D.F. Pacientes: se revisaron 322 expedientes clínicos de pacientes con cáncer colorrectal y cirugía resectiva (colectomías). Las variables analizadas fueron: hemoglobina, hemotocrito pre y postoperatorias, sangrado, transfusión de algún componente sanguíneo durante el periodo transoperatorio y tiempo quirúrgico. Resultados: Solo 268 expedientes tuvieron la información transfunsional requerida. El sangrado promedio por cirugía fue 13.10 por ciento del volumen sanguíneo circulante. Del total de pacientes estudiados 57 por ciento fue transfundido con algún componente sanguíneo. Conclusiones: La incidencia transfunsional fue mayor a la esperada en relación al sangrado quirúrgico, condición que puede afectar el pronóstico de la neoplasia sobre la recurrencia tumoral o supervivencia