Biological responses of Raw 264.7 macrophage exposed to two strains of Stachybotrys chartarum spores grown on four different wallboard types.

The many benefits of building "green" have motivated the use of sustainable products in the design and execution of the built environment. However, the use of these natural or recycled materials, some of which have been treated with antimicrobials, provides a growth opportunity for microorganisms with the potential to elicit adverse health effects especially in the presence of an antimicrobial. The focus of this research was to determine the effects of Stachybotrys chartarum (strains Houston and 51-11) grown under different conditions on a macrophage cell line (Raw 264.7) using endpoints, including cytotoxicity, and those associated with immunity specifically inflammation and MHC class II expression. The fungi were grown on four different gypsum products, and macrophages were exposed to whole spores of both strains and fragmented spores of strain 51-11. Whole spores of the Houston strain elicited no cytotoxicity with some level of inflammation, while exposure to whole spores of 51-11 caused variable responses depending on the wallboard type supporting the fungal growth. High concentrations of fragmented 51-11 spores primarily resulted in the apoptosis of macrophage with no inflammation. None of the fungal strains caused elevated levels of major histocompatibility complex (MHC) class II expression on the surface of Raw cells. Mycotoxin levels of 51-11 spores from all of the wallboard types measured >250 ng/µL of T2 equivalent toxin based on activity. Collectively, the data demonstrated that all of the wallboard types supported growth of fungi with the ability to elicit harmful biological responses with the potential to negatively impact human health.

Mouth opening limitation and influence of age and surgical location for static fully guided dental implant placement: an observational, cross-sectional clinical study.

The influence of age and region of the mouth was assessed in regard to mouth opening in fully guided implant placement. Ninety patients were included in this study, 30 in each of three age groups (20-34, 35-55, and >55 years). Maximum passive mouth opening was recorded in three locations: incisal, canine, and molar. The minimum distance required to allow the bone drilling sequence through a static fully guided approach was analysed for four implant systems: Straumann, MIS Dentsply, Astra Tech Dentsply, and Dentium. The mean ± standard deviation maximum mouth opening (all 90 patients) was 46.34 ± 7.70 mm, 36.82 ± 5.92 mm, and 30.99 ± 5.40 mm in the incisal, premolar, and molar region, respectively. No significant difference in mouth opening at any of the three locations was found between the age groups (all P > 0.05). However, a correlation was found between increasing age and decreasing average mouth opening in all three mouth regions; each additional 1 year resulted in a mean reduction of 0.13 mm, 0.09 mm, and 0.08 mm in the incisal, premolar, and molar region, respectively. The minimum required mouth opening was most likely to be met for implant placement in the incisal region (98.9% of all patients) and least likely to be met for placement in the molar region, particularly for older patients (as low as 30% of patients). Mouth opening remains a major limitation in fully guided implant surgery, especially in posterior areas and in older patients. The use of some implant systems in the posterior area may be limited to only one in three patients.

Dry thermal resistance of Bacillus anthracis (Sterne) spores and spores of other Bacillus species: implications for biological agent destruction via waste incineration.

AIMS: To obtain needed data on the dry thermal resistance of Bacillus anthracis spores and other Bacillus species for waste incinerator applications. METHODS AND RESULTS: Tests were conducted in a pilot-scale incinerator utilizing biological indicators comprised of spores of Geobacillus stearothermophilus, Bacillus atrophaeus and B. anthracis (Sterne) and embedded in building material bundles. Tests were also conducted in a dry heat oven to determine the destruction kinetics for the same species. In the pilot-scale incinerator tests, B. atrophaeus and G. stearothermophilus demonstrated similar thermal sensitivity, but B. anthracis (Sterne) was less thermally resistant than G. stearothermophilus. For the dry heat oven tests conducted at 175°C, the D-values were 0·4, 0·2 and 0·3 min for B. atrophaeus, B. anthracis (Sterne) and G. stearothermophilus, respectively. CONCLUSIONS: Bacillus anthracis (Sterne) possesses similar or less dry heat resistance compared to B. atrophaeus and G. stearothermophilus. SIGNIFICANCE AND IMPACT OF THE STUDY: Previous studies have demonstrated conditions under which bacterial spores may survive in an incinerator environment. The data from this study may assist in the selection of surrogates or indicator micro-organisms to ensure B. anthracis spores embedded in building materials are completely inactivated in an incinerator.

Mold growth on gypsum wallboard--a summary of three techniques.

Reducing occupant exposure to mold growing on damp gypsum wallboard and controlling mold contamination in the indoor environment was studied through 1) delineation of environmental conditions required to promote and avoid mold growth and 2) efficacy testing of antimicrobial products, specifically cleaners and paints, on gypsum wallboard (GWB) surfaces. The effects of moisture and relative humidity (RH) on mold growth and transport are important in avoiding and eliminating problems. These effects have been demonstrated on GWB and are discussed in this article for use as control guidance. The authors discuss the efficacy of antimicrobial cleaners and paints to remove, eliminate, or control mold growth on GWB. Research to control Stachybotrys chartarum growth using 13 separate antimicrobial cleaners and nine varieties of antimicrobial paint on contaminated GWB was performed in laboratory testing. GWB surfaces were subjected to high RH. GWB control measures are summarized and combined, and the antimicrobial product results are explained.

Resin-Dentin Bonding Interface: Mechanisms of Degradation and Strategies for Stabilization of the Hybrid Layer.

Several studies have shown that the dentin-resin interface is unstable due to poor infiltration of resin monomers into the demineralized dentin matrix. This phenomenon is related to the incomplete infiltration of the adhesive system into the network of exposed collagen fibrils, mainly due to the difficulty of displacement and subsequent replacement of trapped water between interfibrillar spaces, avoiding adequate hybridization within the network of collagen fibrils. Thus, unprotected fibrils are exposed to undergo denaturation and are susceptible to cyclic fatigue rupture after being subjected to repetitive loads during function. The aqueous inclusions within the hybrid layer serve as a functional medium for the hydrolysis of the resin matrix, giving rise to the activity of esterases and collagenolytic enzymes, such as matrix metalloproteinases, which play a fundamental role in the degradation process of the hybrid layer. Achieving better interdiffusion of the adhesive system in the network of collagen fibrils and the substrate stability in the hybrid layer through different strategies are key events for the interfacial microstructure to adequately function. Hence, it is important to review the factors related to the mechanisms of degradation and stabilization of the hybrid layer to support the implementation of new materials and techniques in the future. The enzymatic degradation of collagen matrix, together with resin leaching, has led to seeking strategies that inhibit the endogenous proteases, cross-linking the denudated collagen fibrils and improving the adhesive penetration removing water from the interface. Some of dentin treatments have yielded promising results and require more research to be validated. A longer durability of adhesive restorations could resolve a variety of clinical problems, such as microleakage, recurrent caries, postoperative sensitivity, and restoration integrity.

Testing antimicrobial paint efficacy on gypsum wallboard contaminated with Stachybotrys chartarum.

The goal of this research was to reduce occupant exposure to indoor mold through the efficacy testing of antimicrobial paints. An accepted method for handling Stachybotrys chartarum-contaminated gypsum wallboard (GWB) is removal and replacement. This practice is also recommended for water-damaged or mold-contaminated GWB but is not always followed completely. The efficacy of antimicrobial paints to eliminate or control mold regrowth on surfaces can be tested easily on nonporous surfaces. The testing of antimicrobial efficacy on porous surfaces found in the indoor environment, such as gypsum wallboard, can be more complicated and prone to incorrect conclusions regarding residual organisms. The mold S. chartarum has been studied for toxin production and its occurrence in water-damaged buildings. Research to control its growth using seven different antimicrobial paints and two commonly used paints on contaminated, common gypsum wallboard was performed in laboratory testing at high relative humidity. The results indicate differences in antimicrobial efficacy for the period of testing, and that proper cleaning and resurfacing of GWB with an antimicrobial paint can be an option in those unique circumstances when removal may not be possible.

[A brief history of marijuana in the western world]. / Breve historia sobre la marihuana en Occidente.

Marijuana is a substance with a long and controversial history. At different times in its history, which goes back over 5,000 years, this plant has been used for different purposes, ranging from recreational and leisure to its use in the treatment of several diseases or to offer relief in processes that entail a certain type of malaise, and including its consideration as a means of relaxation and meditation. Although it was supposed that the roots of marijuana lay in Central America, it is now known that this is but an urban legend with little credibility and that its origins can be found recorded in Chinese medical references dating back to the year 2737 BC. Although this plant was not originally from Central America, it has aroused interest around the world, and above all in Mexico. It is in this country where the use of cannabis has gone from applications in textiles and medicine to its free sale, the bans on its use due to political and social pressures, its tolerance and, recently, its decriminalisation for recreational and medicinal use. Unfortunately there are few references on the history of this plant in Mexico, and thus we have considered it interesting to present some data about the generalities of marijuana, a brief history in the world, the development of decriminalisation in North America, its medicinal uses and its course through Mexico to the present day.

TITLE: Breve historia sobre la marihuana en Occidente.La marihuana es una sustancia con una extensa y controvertida historia. A lo largo del tiempo, esta planta, y desde hace mas de 5.000 años, ha sido utilizada para diferentes fines, que van desde el uso ludico y recreativo, pasando por un medio de relajacion y meditacion, hasta su uso en el tratamiento de varias enfermedades o el alivio de procesos vinculados a cierto tipo de malestares. Aunque se supuso que la marihuana tenia su origen en Mesoamerica, ahora se sabe que es solo una leyenda urbana de poca credibilidad y que sus origenes los podemos registrar en referencias medicas chinas datadas alrededor del año 2737 a. de C. Si bien esta planta no tiene un origen mesoamericano, si ha generado interes en el mundo, y sobre todo en Mexico. Es en este pais donde el uso del cannabis ha ido desde intereses textiles y medicinales hasta el consumo ludico, pasando por su venta libre, la prohibicion por presiones politicas y sociales, su tolerancia y, recientemente, su despenalizacion para uso ludico y medicinal. Desgraciadamente existen pocas referencias de la historia de esta planta en Mexico, por lo que ha sido de nuestro interes presentar algunos datos sobre las generalidades de la marihuana, una breve historia en el mundo, el desarrollo de la despenalizacion en Norteamerica, sus usos medicinales y su paso por Mexico hasta nuestros dias.

Method for evaluating mold growth on ceiling tile.

A method to extract mold spores from porous ceiling tiles was developed using a masticator blender. Ceiling tiles were inoculated and analyzed using four species of mold. Statistical analysis comparing results obtained by masticator extraction and the swab method was performed. The masticator method was demonstrated as efficient for bulk sampling of ceiling tiles.

Respiratory failure and death following acute inhalation of mercury vapor. A clinical and histologic perspective.

A family of four was exposed to toxic levels of mercury vapor while attempting to extract silver from mercury amalgam. All four suffered respiratory failure and subsequent death despite chelation therapy with dimercaprol. Histologic findings at autopsy were similar in all four cases demonstrating a progression of acute lung injury that appeared related to postexposure day survival. There were no clinical signs of extrapulmonary manifestations despite toxic serum mercury levels. Although serum mercury levels decreased in response to the mercury chelating agent dimercaprol, serum levels remained in the toxic range and no clinical response was observed. Acute inhalational exposure to high concentrations of mercury vapor causes pneumonitis that can lead to respiratory failure and death. This continues to be a health hazard in both the workplace and the home environment.

Enzyme activities and substrate degradation during white rot fungi growth on sugar-cane straw in a solid state fermentation.

Two strains of Pleurotus spp., grown in solid state fermentation on sugar-cane straw, degraded the dry matter by 50% after 60 days. The rate of substrate consumption and the dry weight of fruiting bodies decreased in consecutive flushings. Both strains vigorously attacked hemicellulose (80% of total degradation) and lignin (70%). Fruiting bodies were rich in protein and lipids, and had a low content of carbohydrates and ash.

Bioconversion of sugar cane crop residues with white-rot fungiPleurotus sp.

Four mushroom strains ofPleurotus spp. were cultivated on sugar cane crop residues for 30 days at 26°C. Biochemical changes affected the substrate as a result of fungal growth, in terms of nitrogen, lignin, cellulose and hemicellulose contents. All strains showed a strong ligninolytic activity together with variable cellulolytic and xylanolytic action.Pleurotus sajor-caju attacked lignin and cellulose at the same rate, showing a degradation of 47% and 55%, respectively. A better balance was shown by theP. ostreatus-P. pulmonarius hybrid, which exhibited the poorest cellulolytic action (39%) and the highest ligninolytic activity (67%). The average composition of mushroom fruit bodies, in terms of nitrogen, carbohydrates, fats and amino acid profiles, was determined. Crude protein and total carbohydrate varied from 23% to 33% and 36% to 68% of dry matter, respectively. Fat ranged from 3.3% to 4.7% and amino acid content from 12.2% to 22.2%. Slight evidence for a nitrogen fixing capability was encountered in the substrate to fruit body balance.

Reconstrucción facial con colgajos locales / Facial reconstruction with local flaps

Este trabajo tiene como objetivo conocer la evolución clínica de pacientes sometidos a reconstrucciones faciales con empleo de colgajos locales. Estudio prospectivo, descriptivo y observacional, diseño no experimental. Se presentan cuatro (4) casos clínicos, pacientes masculinos, a dos (2), se les diagnóstica mediante biopsia Carcinoma Basocelular, a uno (1) Carcinoma Espinocelular y al otro Carcinoma Epidermoide, se les practica excéresis de las lesiones que presentan y posteriormente en el mismo acto quirúrgico, se realiza colocación de colgajos, utilizando para ésto piel y en un caso músculo, de diferentes regiones de la cara. Evolución funcional y estética satisfactoria.

Quemaduras: rutina de atención quirúrgica / Burns: routine surgical care

La destrucción de los tegumentos, incluso en los tejidos subyacentes, bajo el efecto de un agente térmico, eléctrico, químico o radioactivo; está en relación con la extensión y profundidad de la lesión nos lleva como definición a una patología extremadamente grave y compleja. Presentamos de manera sucinta la incidencia de quemaduras, rutina de atención al quemado y el resultado de aplicación de esta rutina en el Instituto Autónomo Hospital Universitario de Los Andes, Hospital tipo IV, situado en Mérida Edo. Mérida desde el 2000 hasta el 2006 y que por su área de atención, nuestro Servicio está comprometido en el manejo quirúrgico de estas lesiones, sin embargo aun teniendo la necesidad de poseer un área especial para la atención de los pacientes quemados, no contamos con dicha infraestructura.