Biopolymeric Fibrous Aerogels: The Sustainable Alternative for Water Remediation.

The increment in water pollution due to the massive development in the industrial sector is a worldwide concern due to its impact on the environment and human health. Therefore, the development of new and sustainable alternatives for water remediation is needed. In this context, aerogels present high porosity, low density, and a remarkable adsorption capacity, making them candidates for remediation applications demonstrating high efficiency in removing pollutants from the air, soil, and water. Specifically, polymer-based aerogels could be modified in their high surface area to integrate functional groups, decrease their hydrophilicity, or increase their lipophilicity, among other variations, expanding and enhancing their efficiency as adsorbents for the removal of various pollutants in water. The aerogels based on natural polymers such as cellulose, chitosan, or alginate processed by different techniques presented high adsorption capacities, efficacy in oil/water separation and dye removal, and excellent recyclability after several cycles. Although there are different reviews based on aerogels, this work gives an overview of just the natural biopolymers employed to elaborate aerogels as an eco-friendly and renewable alternative. In addition, here we show the synthesis methods and applications in water cleaning from pollutants such as dyes, oil, and pharmaceuticals, providing novel information for the future development of biopolymeric-based aerogel.

Fast cyclical-decellularized trachea as a natural 3D scaffold for organ engineering.

Commonly reported decellularization protocols for trachea may take up from several weeks to months in order to remove the cellular materials. Two years ago, we significantly reduced the time of decellularization trachea process using trypsin. Despite the positive outcome, the protocol was useful to produce 5 cm graft length, an unsuitable length graft for most patients with tracheal disorders. In this work we improved the decellularization procedure for longer sections up to 10 cm without considerable extension in the necessary time process (2 weeks). Herein, for the first time, we completely describe and characterize the process for pig tracheal bioactive scaffolds. Histological and molecular biology analysis demonstrated effective removal of cellular components and nuclear material, which was also confirmed by the Immunohistochemical (IHC) analysis of the major histocompatibility complexes (MHCs) and DNA stain by 4'-6-diamidino-2-phenylindole (DAPI). The images and data obtained from scanning electron microscopy (SEM) and thermal analysis showed conservation of the hierarchical structures of the tracheal extracellular matrix (ECM), the biomechanical tests showed that decellularization approach did not lead to a significant alteration on the mechanical properties. In this paper, we demonstrate that the proposed cyclical-decellularization protocol allowed us to obtain a non-immunological 10 cm natural tracheal scaffold according to the in vivo immunological assessment. Furthermore, the recellularization of the matrix was successfully achieved by demonstrating first-stage cellular differentiation from stem cells to chondrocytes expressed by the SOX9 transcription factor; this organ-engineered tracheal matrix has the potential to act as a suitable template for organ regeneration.

Effect of Ions Released and pH of Two Glass Ionomer Cements in Human Gingival Fibroblasts / Efecto de la liberación de iones y pH de dos cementos de ionómero de vidrio en fibroblastos gingivales humanos

Abstract 20. Conventional glass ionomer cements are used as dental provisional restorative materials, which present several advantages such as adhesion to the tooth mineral phase among others. On the other hand, the knowledge about biological property of glass ionomers shows various approaches and results. In this work, it was studied the in vitro biological response of human gingival fibroblasts in contact with commercial cements of glass ionomer: Mirafil® and Ionglass® and with their extracts, according to ISO 10993. The extracts of the cements, in which the cells were cultured, were adjusted at different concentrations ranging 0.1% to 100%. The cellular metabolic activity of gingival fibroblasts was measured using the Alamar Blue® reagent. The results showed a significant effect on the cellular metabolic activity correlated with the concentration of liberated ions (Al³+ and Ca²+) for both ionomers, as well as the pH variations of the culture media. This could mean that the cellular metabolic activity is substantially influenced by ions and pH of the cell culture.

Resumen 24. Los cementos de ionómero de vidrio convencionales se utilizan como materiales de restauración provisional para uso dental, los cuales presentan varias ventajas como la adhesión a la fase mineral de los dientes. Por otro lado, las propiedades biológicas de los ionómeros de vidrio muestran diversos enfoques y resultados. En éste trabajo se estudió la respuesta biológica in vitro de fibroblastos gingivales humanos en contacto con cementos comerciales de ionómero de vidrio: Mirafil® e Ionglass® y con sus respectivos extractos según la norma ISO 10993. Los extractos de los cementos en los que se cultivaron las células estaban en diferentes concentraciones: de 0.1% a 100%. La actividad metabólica celular se midió usando el reactivo Alamar Blue®. Los resultados mostraron un efecto significativo sobre la actividad metabólica celular correlacionada con la concentración de iones liberados (Al³+ y Ca²+) para ambos ionómeros, así como las variaciones de pH de los medios de cultivo. Ello podria explicar la influencia por los iones y el pH del cultivo celular en la actividad metabólica celular.

[Bone loss treatment, pseudoarthrosis, arthrodesis and benign tumors using xenoimplant: clinical study].

BACKGROUND: Bone loss as a result of arthrodesis, pseudarthrosis, benign tumors and bone defects was treated using a xenoimplant (Nukbone). METHODS: The effectiveness of the material was evaluated through a longitudinal and observational study at the Hospital Regional "General Ignacio Zaragoza" (HRGIZ) ISSSTE. The Mexican xenoimplant is a patent of the National Autonomous University of Mexico (UNAM). RESULTS: Fifty two patients were considered regardless of age or gender. Of these patients, 28 were male and 24 female. Average age of the patients was 47.7 years (9-84 years). Twenty eight patients had arthrodesis, 16 were treated with pseudarthrosis, three patients had benign tumors and five patients presented bone defects, which were implanted with Nukbone at the site and was the correct treatment for the problem. The xenoimplant is fully integrated during a period of 3-18 months, depending on the size of the pathology and the region where it was placed. Fracture healing was evaluated radiographically according to the classification of Montoya. No patient had clinical signs of rejection. CONCLUSIONS: In Mexico, bony xenoimplants (osseous) have been used, all of foreign origin due to the high degree of technological dependence in this country. In this study we describe the use, for the first time, of a Mexican xenoimplant with a patent from the Universidad Nacional Autónoma de México (UNAM). The Mexican xenoimplant is biocompatible and can be adapted to treat pathologies where bony (osseous) material is needed.

Tratamiento de pérdidas óseas, pseudoartrosis, artrodesis y tumores óseos benignos con un xenoimplante mexicano (estudio clínico) / Bone loss treatment, pseudoarthrosis, arthrodesis and benign tumors using xenoimplant: clinical study

Objetivo: Se trataron pérdidas óseas, artrodesis, pseudoartrosis, tumores benignos y defectos óseos con un xenoimplante. Material y métodos: Se evaluó la eficacia del material mediante un estudio observacional y longitudinal en el Hospital Regional “General Ignacio Zaragoza” del ISSSTE. Resultados: Fueron considerados 52 pacientes, 28 masculinos y 24 femeninos, de los cuales a 28 se les practicó artrodesis, 16 fueron tratados por pseudoartrosis, tres presentaron tumores óseos benignos y cinco defectos óseos, a los cuales se les colocó el xenoimplante en el sitio y forma adecuada según el problema por tratar. El promedio de edad de los pacientes fue de 47.7 años, con un rango de nueve a 84 años. Se presentó consolidación ósea entre los tres y ocho meses después de la cirugía; el xenoimplante se integró totalmente en un periodo de tres a 18 meses dependiendo del tamaño de la patología y la región donde fue colocado. La consolidación ósea fue valorada radiográficamente de acuerdo con la clasificación de Montoya. Ningún paciente presentó signos clínicos de rechazo. Conclusiones: En México se han empleado xenoimplantes óseos de origen extranjero debido a la gran dependencia tecnológica del país. Por primera vez se utiliza un xenoimplante producido en el país y cuya patente es de la Universidad Nacional Autónoma de México. El xenoimplante Nukbone® fue biocompatible y resultó adecuado para tratar patologías donde se requiere aporte óseo.

BACKGROUND: Bone loss as a result of arthrodesis, pseudarthrosis, benign tumors and bone defects was treated using a xenoimplant (Nukbone). METHODS: The effectiveness of the material was evaluated through a longitudinal and observational study at the Hospital Regional "General Ignacio Zaragoza" (HRGIZ) ISSSTE. The Mexican xenoimplant is a patent of the National Autonomous University of Mexico (UNAM). RESULTS: Fifty two patients were considered regardless of age or gender. Of these patients, 28 were male and 24 female. Average age of the patients was 47.7 years (9-84 years). Twenty eight patients had arthrodesis, 16 were treated with pseudarthrosis, three patients had benign tumors and five patients presented bone defects, which were implanted with Nukbone at the site and was the correct treatment for the problem. The xenoimplant is fully integrated during a period of 3-18 months, depending on the size of the pathology and the region where it was placed. Fracture healing was evaluated radiographically according to the classification of Montoya. No patient had clinical signs of rejection. CONCLUSIONS: In Mexico, bony xenoimplants (osseous) have been used, all of foreign origin due to the high degree of technological dependence in this country. In this study we describe the use, for the first time, of a Mexican xenoimplant with a patent from the Universidad Nacional Autónoma de México (UNAM). The Mexican xenoimplant is biocompatible and can be adapted to treat pathologies where bony (osseous) material is needed.

[Mexican ceramic material for skin healing]. / Cerámicas mexicanas para cicatrización de piel.

Sixty female Wistar rats were employed and divided into three experimental groups of 20 rats each. Groups were evaluated at 15, 30, and the last at 45 days after surgery. Each group was divided into four sets of five rats each. All rats were subjected to surgery; an incision of 2 x 2 cm was done on the back of each animal, removing tissue until reaching muscular fascia, where the material was applied. Nitro-furazone was employed as positive control. Test materials were AlPO added with 0.55% wt of Zn; 0.30% wt of Ca(OH)2, and AlPO added with 0.55% wt of Zn and 0.66% wt of Ca(OH)2. Finally, as negative control no material was used. The object of this work was in the first place obtension of test materials and to evaluate the healing skin process in rats using AlPO enriched with Zn and Ca(OH)2; as indicated previously. Obtained materials were characterized employing XRD. Histologic studies tested showed that best healing process of dermal tissue corresponded to rats treated with AlPO added with 0.55% wt of Zn and 0.30% wt of Ca(OH)2. Use of AlPO ceramics to repair skin has not been reported previously.

Cerámicas mexicanas para cicatrización de piel / Mexican Ceramic Material for Skin Healing

Se utilizaron 60 ratas Wistar, que fueron evaluadas a los 15, 30 y 45 días después de la cirugía. Se quitó un cuadro de piel del lomo del animal, removiendo la epidermis y la dermis hasta alcanzar la fascia muscular donde se aplicó el material de experimentación. Se usó Nitrofurazona como control positivo y ningún material como control negativo. Los materiales a probar fueron fosfatos de aluminio a los que se agregó: 0.55% en peso de Zn y 0.30% en peso de Ca(0H)2 siendo éste el material A, y 0.55% en peso de Zn y 0.66% en peso de Ca(0H)2 el material B. Se trataron cinco ratas con cada material. Los objetivos del trabajo fueron la obtención de las cerámicas a probar y la evaluación de su efecto sobre el proceso de cicatrización de piel de ratas. Los materiales obtenidos fueron caracterizados con DRX. Estudios histopatológicos probaron que los mejores procesos de cicatrización de la piel se observaron en las ratas tratadas con el material A. El uso de las cerámicas AlPO para cicatrización de piel no ha sido reportado antes.

Sixty female Wistar rats were employed and divided into three experimental groups of 20 rats each. Groups were evaluated at 15, 30, and the last at 45 days after surgery. Each group was divided into four sets of five rats each. All rats were subjected to surgery; an incision of 2 x 2cm was done on the back of each animal, removing tissue until reaching muscular fascia, where the material was applied. Nitro-furazone was employed as positive control. Test materials were AlPO added with 0.55% wt of Zn; 0.30% wt of Ca(OH)2 and AlPO added with 0.55% wt of Zn and 0.66% wt of Ca(0H)2. Finally, as negative control no material was used. The object of this work was in the first place obtension of test materials and to evaluate the healing skin process in rats using AlPO enriched with Zn and Ca(0H)2; as indicated previously. Obtained materials were characterized employing XRD. Histologic studies tested showed that best healing process of dermal tissue corresponded to rats treated with AlPO added with 0.55% wt of Zn and 0.30% wt of Ca(OH)2. Use of AlPO ceramics to repair skin has not been reported previously.

Evaluación radiográfica de implantes de zinalco en fémur de perros / Radiographic evaluation of zinalco implants (80 percent Zn - 18 percent Al - 2 percent Cu), zinalco coated with titanium nitride and stainles steel 316L in dogs femur

Este trabajo es la búsqueda de nuevas alternativas para probar materiales con aplicaciones médicas. Se emplearon cuatro perros mestizos a los que se les implantaron cilindros de zinalco y acero 3l6L en los tercios proximal y distal del fémur izquierdo, respectivamente. El propósito fue evaluar la biocompatibilidad de estos materiales desde el punto de vista clínico, para lo cual se llevó a cabo el estudio radiográfico previo y posterior a la cirugía a los 30, 60, 90 y 120 días, evaluándose la densidad ósea, el rechazo al implante, signos de metalosis y reacción perióstica. En todos los casos hubo formación de hueso adyacente a los implantes, observada radiográficamente por reacción perióstica laminar, endostitis y esclerosis del canal medular. No se observaron reacciones periósticas severas e irregulares ni reabsorción ósea. No hubo evidencias de rechazo en los perros implantados a los 120 días de implantación de los materiales evaluados

Estudio preliminar de la biocompatibilidad de la aleación zinalco / Preliminary study of Zinalco alloy biocompatibility

Hasta ahora las aleaciones a base de zinc y aluminio no han sido consideradas para uso médico por su baja resistencia a la corrosión; sin embargo, la aleación zinalco, de desarrollo reciente, posee gran resistencia mecánica y a la corrosión, por lo que ha sido de interés probar su biocompatibilidad para ser usada como material de implante. En este trabajo se estudia la respuesta del tejido aledaño a implantes de zinalco de 8 x 4 x 1 mm colocados tanto en forma subcutánea (Sc) como intermuscular (Im) en ratas hembras Wistar, usando como variables testigo, las obtenidas de ratas no implantadas (T). La respuesta clínica de los animales fue evaluada por dos observadores independientes. Al final de cada periodo se sacrificaron 4 animales con implantación Sc, 4 con implante Im y 2 ratas T, con sobredosis anestésica. Previo al sacrificio, se tomaron muestras sanguíneas de ellas para determinar la concentración de Zn A1 y Cu por el método de espectroscopia de absorción atómica (EAA). Desde el punto de vista clínico los animales mostraron una respuesta inflamatoria normal; los niveles de los metales en la sangre de las ratas implantadas no presentaron diferencias significativas en las medidas promedio obtenidas con respecto a las testigo. En el estudio histopatológico se observó neoformación de vasos sanquíneos, presencia de material amorfo aparentemente procedente del implante, mismo que se encuentra rodeado de tejido fibroso denso irregular infiltrado por leucocitos mononucleares. La reacción fue más severa en los implantes subcutáneos que en los intermusculares. Finalmente, en órganos perenquimatosos no se observó alteración