3-Methyl-2-benzothiazolinone hydrazone and 3-dimethylamino benzoic acid as substrates for the development of polyphenoloxidase and phenoloxidase activity by zymograms.

In the present study, a sequential staining process of polyphenoloxidase and phenoloxidase enzymes was designed by the zymography technique. As a first step, electrophoresis was carried out under native conditions, and later, first staining was carried out with a revealing solution of 3-methyl-2-benzothiazoline hydrazone (MBTH)-3-dimethylamino benzoic acid (DMAB) that allowed the visualization of polyphenoloxidase enzymes, and later and using the same gel, we proceeded to the differential staining of phenoloxidase, adding a solution of H2O2. The technique was standardized using commercial enzymes of laccase (T. versicolor) and horseradish. The technique was used to identify polyphenoloxidases (laccases) and phenoloxidases (lignin peroxidase) of crude extracts obtained from the growth of the basidiomycete Lentinus strigosus on Pinus radiata. The technique showed great sensitivity to detect the different enzymatic activities (1.56 Activity Unit/mL minimum) in the same gel without interference between the enzymes and the solutions used. On the other hand, the efficiency of the technique was compared with the substrates that are commonly used for the detection of this type of activities such as 2,2'-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) and guaiacol, observing greater sensitivity and minimal interference, so that the present method will allow in the same gel, and visualize polyphenoloxidase and phenoloxidase activities simultaneously facilitating expression studies.

Photocatalytic behavior for the phenol degradation of ZnAl layered double hydroxide functionalized with SDS.

Functionalized ZnAl layered double hydroxide based photocatalyst was obtained by the addition of sodium dodecyl sulfate (SDS) during the synthesis by the coprecipitation method, and further calcination at 400 °C. Bare and modified materials were characterized by X-ray diffraction, nitrogen adsorption-desorption, IR, UV-Vis, EPR and XPS spectroscopies, SEM and HRTEM. The synthesized material was evaluated in the photodegradation of phenol in a 40 ppm aqueous solution (4.25 × 10-4 mol of phenol/L), under UV light irradiation. An increasing in the degradation of phenol from 62 to 95%, and from 62 to 82% in the mineralization of phenol was obtained using SDS functionalized ZnAl LDH, in comparison with the unmodified material. This increase could be attributed to the presence of sulfate radicals, confirmed by the EPR study.

Isolation and Selection of Streptomyces Species from Semi-arid Agricultural Soils and Their Potential as Producers of Xylanases and Cellulases.

The Mezquital Valley (MV), Mexico, is a semi-arid region whose main economic activity is agriculture, this zone is characterized by the use of wastewater for crop irrigation. This condition has increased the amount nutrients in soils, organic carbon content and native microorganisms. The Streptomyces species are a group of saprophytic bacteria that represent between 20 and 60% of the total microbial population in soils, capable of producing metabolites of commercial importance. In this work, Streptomyces species were isolated from agricultural soils of the MV and was evaluated the production of endoglucanases (CMCase) and xylanases (Xyl) in Solid-State Cultivation (SSC). From soil samples, 73 possible strains of Streptomyces species were isolated for their ability to produce CMCase and Xyl in SSC. The study also included its characterization by morphological characteristics. Of the isolated microorganisms, 38 strains were selected as strong enzyme producers according to the measurement of the halo generated in plate and by growth on barley straw as only carbon source. Two different sizes of barley straw particle were tested, finding that the greatest enzymatic activity was observed in particle size 12. Three strains of Streptomyces species were chosen which presented the best catalytic capacities, a maximum of 100.69 AU Xyl/gram dry matter (gdm), 82 AU Xyl/gdm and 26.02 AU CMCase/gdm for strains 30, 28 and 12, respectively. The strains were identified by ribosomal gen16s sequence and identified as S. flavogriseus, S. virginiae and S. griseoaurantiacus. It is the first report of endogluconase and xylanolytic activity by S. virginiae isolated from a semi-arid soil.

Use of barley straw as a support for the production of conidiospores of Trichoderma harzianum.

In this work was to evaluate the conidiospores production of Trichoderma harzianum using barley straw as substrate. Four growth conditions were used; washed and unwashed barley straw and washed and unwashed barley straw supplemented with mineral salts. The highest spore production was observed when washed barley straw supplemented with mineral salts with 1.56 × 1010 conidiospores/gram of dry matter (gdm) at 216 h of cultivation was used. The effect of substrate moisture on spore production was studied, three initial moisture levels of the substrate were tested and it was observed that a humidity of 80 % of the substrate improves the production of conidiospores reaching a concentration of 2.35 × 1010 conidiospores/gdm at 136 h. Finally, conidiospores viability was evaluated for 12 months by keeping them on the conidia and substrate, and viability of 71 % of the conidiospores was observed, so this maintenance method is an excellent means of conserving the conidiospores viability.

Experiencias y creencias de madres sobre la lactancia materna exclusiva en una región de México / Experiences and beliefs of mothers about exclusive breastfeeding in a region of Mexico

Objetivo: explorar las experiencias y creencias sobre la lactancia materna exclusiva de madres que acuden a consulta nutricional a un hospital público. Método: se llevó a cabo un estudio cualitativo en la ciudad de Soledad de Graciano Sánchez, México. Participaron 31 madres lactantes en cuatro grupos focales. Se realizó análisis de contenido convencional. Resultados: las participantes reconocen la lactancia materna como la alimentación ideal para sus hijos, no obstante, señalan carencias de información en materia de lactancia y abogan por una orientación más completa y veraz. Diversas circunstancias comprometen el amamantamiento y hacen la lactancia poco placentera en términos de sensación física. Las mujeres resaltan el papel de la madre y abuela como principal fuente de apoyo e información a diferencia del personal de salud. Consideraciones finales: la educación en lactancia humana debe fortalecerse. El personal sanitario debe incrementar su papel y presencia para promover la lactancia materna exclusiva.

Objetivo: explorar as experiências e crenças sobre a amamentação exclusiva de mães que chegam a um hospital público para consulta nutricional. Método: um estudo qualitativo foi realizado na cidade de Soledad de Graciano Sánchez, no México. 31 mães lactantes participaram de quatro grupos focais. A análise do conteúdo convencional foi realizada. Resultados: os participantes reconhecem a amamentação como a dieta ideal para seus filhos, no entanto, apontam a falta de informação sobre a amamentação e defendem uma orientação mais completa e verdadeira. Diversas circunstâncias comprometem a amamentação e tornam a amamentação desagradável em termos de sensação física.As mulheres destacam o papel da mãe e da avó como principal fonte de apoio e informação, diferentemente do pessoal de saúde. Considerações finais: a educação em lactação humana deve ser fortalecida. O pessoal de saúde deve aumentar seu papel e presença para promover o aleitamento materno exclusivo.

Objective: explore the experiences and beliefs about exclusive breastfeeding of mothers who come to a public hospital for nutritional consultation. Methods: a qualitative study was carried out in the city of Soledad de Graciano Sánchez, Mexico. 31 lactating mothers participated in four focus groups. Analysis of conventional content was carried out. Results: the participants recognize breastfeeding as the ideal diet for their children, however, they point out the lack of information on breastfeeding and they advocate a more complete and truthful orientation. Various circumstances compromise breastfeeding and make breastfeeding unpleasant in terms of physical sensation. Women highlight the role of the mother and grandmother as the main source of support and information unlike the health personnel. Final consideration: the education in human lactation should be strengthened. Health personnel should increase their role and presence to promote exclusive breastfeeding.

Thermoluminescent dosimetry in veterinary diagnostic radiology.

This paper presents the results of Environmental and Personnel Dosimetry made in a radiology area of a veterinary hospital. Dosimetry was realized using thermoluminescent (TL) materials. Environmental Dosimetry results show that areas closer to the X-ray equipment are safe. Personnel Dosimetry shows important measurements of daily workday in some persons near to the limit established by ICRP. TL results of radiation measurement suggest TLDs are good candidates as a dosimeter to radiation dosimetry in veterinary radiology.

Screening for thermotolerant ligninolytic fungi with laccase, lipase, and protease activity isolated in Mexico.

The State of Hidalgo (Mexico) has a large area of forests known as the Huasteca Hidalguense, with a large variety of microorganisms inhabiting it. They represent an important resource from the ecological and technological point of view because they can be used in a broad variety of industrial processes. Due to the climatic conditions of this region, fungi inhabiting it must be thermophile or, at least, thermotolerant, as temperatures can be higher than 45°C in the summer, declining to 20°C in the winter. Use of ligninolytic fungi relies on their capacity to produce enzymes of industrial interest, a topic that has been under continuous research by academic and industrial investigators. Among the most important enzymes are proteases that are widely used due to their biotechnological applications with a high economic impact. Other enzymes, laccases, peroxidases, and lipases are of interest for the industries of the state of Hidalgo, especially in the textile industry, specifically in effluent processing. Fungi (n=156) were collected in the Huasteca Hidalguense, of which 100 were isolated in potato-dextrose-agar covered plates and maintained in tilted tubes. Afterwards, enzymatic activity (laccase, protease and lipase) was determined in the plates. The purpose was to select those fungi with the highest potential for biotechnological applications. Fungi generally grew at either 30°C or 37°C, and for some isolates enzymatic activities were detected at this higher temperature. Results are presented as the relation between enzymatic activity and growth rate: 60 fungi presented laccase activity, 49 had lipase activity, and none had protease activity. In most cases, enzymatic activity was higher than the growth rate, indicating that the isolated fungi have a great biotechnological potential. Statistical analysis revealed that isolates 31 (Trametes) and 8.1 (unidentified) have a larger potential to be studied as laccase-producing fungi. On the other hand, isolates 144.2 (Fomes), 154 (Trametes), and 147.2 (Pycnoporus) are of interest as lipase activity producers, an activity scarcely studied in this type of microorganisms.

Frozen allogeneic human epidermal cultured sheets for the cure of complicated leg ulcers.

BACKGROUND: Skin ulcers due to venous stasis or diabetes are common among the elderly and are difficult to treat. Repeated applications of cell-based products have been reported to result in cure or improvement of leg ulcers of small size in a fraction of patients. OBJECTIVE: To examine the effects of frozen human allogeneic epidermal cultures for the treatment of acute and chronic ulcers. METHODS: We treated a series of 10 consecutive patients with leg ulcers of different etiology and duration with frozen human allogeneic epidermal cultures stored frozen and thawed for 5-10 minutes at room temperature before application. Three patients had ulcers with exposed Achilles or extensor tendon. The ulcers treated were as large as 160 cm2 in area and of up to 20-years' duration. After preliminary preparation of the wounds by debridement to remove necrotic tissue and application of silver sulfadiazine to control infection, thawed cultures were applied biweekly from 2 to 15 times depending on the size and complexity of the ulcer. RESULTS: All ulcers healed, including those with tendon exposure. After the first few applications, granulation tissue formed in the ulcer bed and on exposed tendons, and epidermal healing took place through proliferation and migration of cells from the margins of the wound. The time required for complete healing ranged from 1 to 31 weeks after the first application. CONCLUSION: The use of frozen human allogeneic epidermal cultures is a safe and effective treatment for venous or diabetic ulcers, even those with tendon exposure. It seems possible that any leg ulcer will be amenable to successful treatment by this method.

Neovagina with cultured allogenic epidermal sheets.

Several materials have been used in neovagina construction, but most of them show some kind of drawback. This is the report of a case in which cultured allogenic epidermal sheets were used instead of skin grafting for a McIndoe procedure.

Autoinjertos de piel obtenidos por el cultivo in vitro de celulas epidérmicas / In vitro cultivated skin autograts

El paciente extensamente quemado se encuentra en riesgo de infección y muerte por falta de cubierta cutánea siendo el índice de mortalidad hasta de un 80% o mayor en los casos en que las quemaduras ocupan más del 60 al 70% de la superficie corporal total. Se ha tratado de producir, por diversos procedimientos, cubierta cutánea suficiente para estos pacientes qquemados; entre estos procedimientos se ha recurrido al cultivo in vitro de células epidérmicas. Uno de los más adecuados ha sido el reportado por Rheinwald y Green (Cell 6: 331-343, 1975), que permite la formación, en cultivo, de epitelios estratificados de manera similar a la epidermis (Gren et al, PNAS-USA. 76: 5665-5668, 1979). En este trabajo reportamos, en México, un primer caso de epidermis cultivada in vitro para el autoinjerto en un niño que sufrió quemaduras por líquidos en ebullición en diversas partes del cuerpo. Se tomó del mismo paciente, una pequeña biopsia (2-3 cm) de piel no dañada a partir de la cual se cultivaron las células epidérmicas, que en dos períodos de una semana y media cada uno, formaron epitelios estratificados que se despegaron del recipiente del cultivo y se trasplantaron a una área cruenta de tercer grado del muslo derecho, de aproximadamente 150 cm de superficie. Los epitelios cultivos se integraron al lecho receptor en 8 a 10 días y formaron una epidermis de características similares a la que se produce por epitelización espontánea. Los autoinjertos obtenidos por medio del cultivo in vitro de células epidérmicas pueden ser una terapia definitiva para el paciente extensamente qquemado para quien es fundamental la formación de epidermis. Es de esperar que el epitelio cultivado para el autoinjerto o el aloinjerto llegue a formar parte del tratamiento rutinario en pacientes qquemados con otros daños epidérmicos