Locust bean gum hydrogels are bioadhesive and improve indole-3-carbinol cutaneous permeation: influence of the polysaccharide concentration

Abstract The locust bean gum (LBG) is a polysaccharide with thickening, stabilizing and gelling properties and it has been used in the preparation of pharmaceutical formulations. Hydrogels (HGs) are obtained from natural or synthetic materials that present interesting properties for skin application. This study aimed to develop HGs from LBG using indole-3-carbinol (I3C) as an asset model for cutaneous application. HGs were prepared by dispersing LBG (2%, 3% and 4% w/v) directly in cold water. The formulations showed content close to 0.5 mg/g (HPLC) and pH ranging from 7.25 to 7.41 (potentiometry). The spreadability factor (parallel plate method) was inversely proportional to LBG concentration. The rheological evaluation (rotational viscometer) demonstrated a non-Newtonian pseudoplastic flow behavior (Ostwald De Weale model), which is interesting for cutaneous application. The HET-CAM evaluation showed the non-irritating characteristic of the formulations. The bioadhesive potential demonstrated bioadhesion in a concentration-dependent manner. Permeation in human skin using Franz cells showed that the highest LBG concentration improved the skin distribution profile with greater I3C amounts in the viable skin layers. The present study demonstrated the feasibility of preparing HGs with LBG and the formulation with the highest polymer concentration was the most promising to transport active ingredients through the skin.

Atmospheric evaporative demand and water deficit on the ecophysiology of Rubber seedlings

The search for genetic materials resistant to adverse weather conditions has been a major focus in studies on species of economic interest. The objective of the present study was to assess the growth and photosynthesis of rubber seedlings clones under two conditions of atmospheric evaporative demand, characterized by fluctuations in temperature (TEMP) and vapor pressure deficit (VPD), associated to two water regimens. Hevea brasiliensis Muell. Arg (RRIM 600 and FX 3864) clones were assessed in two microclimates, at low (TEMP 21.2 ºC and VPD 0.29 Kpa) and high (TEMP 26.9 ºC and VPD 1.49 Kpa) atmospheric evaporative demand, under two water regimens: water deficit and well-watered. Water deficit 50% water availability was sufficient to reduce the net CO2 assimilation rate, leaf area and total chlorophyll of the clones studied that impacted growth in both microclimates. The effects of water deficit on growth and net carbon assimilation rate were intensified under high atmospheric evaporative demand. However, when comparing the two clones studied, RRIM 600 showed greater growth and photosynthesis without water restriction. The FX 3864 clone, despite the high CO2 assimilation values under high atmospheric demand and without water restriction, showed a reduced growth. The results of this study form an important basis for the selection of genotypes with the potential to develop in adverse climatic conditions. In this sense, the RRIM 600 genotype is recommended as a promising material that would best adapt under adverse climatic conditions.

In vitro skin retention and drug permeation study of Tongluo-Qutong rubber plaster by UPLC/UV/MS/MS

Abstract Tongluo-Qutong rubber plaster (TQRP), a typical Chinese patent medicine that contains 13 different herbal remedies, is widely used in clinical practice for the treatment of cervical spondylosis and osteoarthritis. However, due to a lack of in vitro transdermal studies, the active ingredients of TQRP have not been fully elucidated. This presents a huge obstacle for quality evaluation, pharmacokinetic studies and clinical safety assessment of TQRP. In this work, a UPLC/UV/MS/MS method was established and validated to evaluate five analytes in TQRP. The validation demonstrated linearity (r > 0.99), specificity (no co-eluting peaks at the retention times of the analytes), and precision (RSD < 15%) within acceptable parameters. A skin permeation study was performed to determine the concentrations of drugs delivered to the dermis. The 24-hour cumulative permeation of ferulic acid, aleo-emodin, emodin and piperine were 303.68, 709.31, 671.06 and 25561.01 ng/cm2, respectively. According to the fitting data of the TQRP active components, skin permeation was mainly due to a combination of passive diffusion and drug release after matrix erosion

Force decay evaluation of latex and non-latex orthodontic intraoral elastics: in vivo study

ABSTRACT Objective: This clinical study was conducted in order to evaluate force decay over time of latex and non-latex orthodontic intraoral elastics. Methods: Patients (n = 15) were evaluated using latex and non-latex elastics in the periods of : 0, 1, 3, 12 and 24 hours. The rubber bands were transferred to the testing machine (EMIC DL-500 MF), and force values were recorded after stretching the elastic to a length of 25mm. Paired t test was applied and analysis of variance (ANOVA) was used to evaluate the variation of force generated. LSD (Fisher's least significant difference) post-hoc test was thus employed. Results: As regards the initial forces (zero time), the values of force for non-latex elastic were slightly higher than for the latex elastic. In the subsequent times, the forces generated by the latex elastic showed higher values. Regarding the material degradation, at the end of 24 hours the highest percentage was observed for non-latex elastic. Conclusions: The latex elastics had a more stable behavior during the studied period, compared with non-latex.

RESUMO Objetivo: o objetivo deste estudo clínico foi avaliar e comparar o comportamento dos elásticos de látex e não látex quanto à perda de força ao longo do tempo. Método: os pacientes (n = 15) foram avaliados usando ambos os tipos de material (látex e não látex) em cada tempo: 0, 1, 3, 12 e 24 horas. Os elásticos foram transferidos para a máquina de ensaios mecânicos (EMIC DL-500 MF) e os valores de força foram registrados após a distensão dos elásticos a uma distância de 25 mm. Foi aplicado o teste t pareado, e a análise de variância (ANOVA) foi realizada para verificar a variação das forças geradas em todos os tempos estudados. Em seguida, o teste post-hoc LSD (Fisher's least significant difference) foi aplicado. Resultados: quanto às forças iniciais (tempo zero), os valores de força dos elásticos não látex foram ligeiramente maiores do que dos elásticos de látex. Nos tempos subsequentes, as forças geradas pelos elásticos de látex apresentaram valores superiores às geradas pelos elásticos não látex. Em relação à degradação do material, ao fim do período de 24 horas, o maior percentual foi observado pelos elásticos não látex. Conclusões: os elásticos de látex apresentaram comportamento mais estável durante o período de estudo, em comparação aos não látex.

Rubber gloves biodegradation by a consortium, mixed culture and pure culture isolated from soil samples

Abstract An increasing production of natural rubber (NR) products has led to major challenges in waste management. In this study, the degradation of rubber latex gloves in a mineral salt medium (MSM) using a bacterial consortium, a mixed culture of the selected bacteria and a pure culture were studied. The highest 18% weight loss of the rubber gloves were detected after incubated with the mixed culture. The increased viable cell counts over incubation time indicated that cells used rubber gloves as sole carbon source leading to the degradation of the polymer. The growth behavior of NR-degrading bacteria on the latex gloves surface was investigated using the scanning electron microscope (SEM). The occurrence of the aldehyde groups in the degradation products was observed by Fourier Transform Infrared Spectroscopy analysis. Rhodococcus pyridinivorans strain F5 gave the highest weight loss of rubber gloves among the isolated strain and posses latex clearing protein encoded by lcp gene. The mixed culture of the selected strains showed the potential in degrading rubber within 30 days and is considered to be used efficiently for rubber product degradation. This is the first report to demonstrate a strong ability to degrade rubber by Rhodococcus pyridinivorans.

Tratamiento de Clase II con Ortodoncia Sistema Damon y gomas intermaxilares en etapas tempranas de tratamiento / Treatment of Class II with Orthodontics Damon System and elastics in early stages of treatment

La técnica ortodóncica de baja fricción utiliza brackets pasivos de autoligado con una serie de arcos superelásticos que mantienen las fuerzas aplicadas sobre las piezas dentarias a nivel de la "biozona o zona fuerza óptima". La utilización de gomas intermaxilares ligeras (2 onzas o 56,68 g) en estos tratamientos, desde etapas iniciales, sobre todo en pacientes en crecimiento, permite obtener resultados muy favorables en cuanto a la resolución de la maloclusión de Clase II. Objetivo: evaluar el tratamiento de Ortodoncia de un paciente Clase II esqueletal con sobremordida, sin realizar exodoncias de premolares y utilizando elásticos intermaxilares en fases iniciales de tratamiento. Materiales y método: se presenta el caso clínico de un paciente de sexo masculino de 11 años, de Clase II esqueletal con sobremordida y apiñamiento dentario anterior superior e inferior moderado, con su diagnóstico y evaluación completos pre y post tratamiento y control y seguimiento al año. El tratamiento se realiza con brackets autoligantes (técnica de Damon). Resultados: se obtiene la corrección completa de la Clase II y la sobremordida, alcanzando los objetivos deseados de estética facial y función, en oclusión y desoclusiones, con buen desarrollo de las basales y conservación de la altura de las corticales alveolares a nivel de los caninos. Conclusión: Mediante los recursos terapéuticos disponibles en la actualidad y evaluando al niño en etapas tempranas, podremos combinar diferentes tratamientos para alcanzar los objetivos propuestos en menor tiempo y con óptimos resultados en una maloclusión de Clase II con sobremordida con biotipo mesofacial (AU)

The low friction orthodontic technique uses passive self-ligating brackets with a series of superelastic arches that maintain the forces applied to the dental pieces at the "Biozone or Optimal Force Zone". The use of inter maxillary light elastics (2 ounces or 56.68 yr.) from the initial stages in growing patients, yields very favorable results in terms of correction of Class II malocclusion. Objective: To assess the orthodontic treatment of a skeletal Class II patient with overbite, without extraction of premolars and using elastic in the early stages of treatment. Materials and methods: an 11 year old male skeletal Class II patient with overbite and moderate crowding in upper and lower anterior teeth, with complete diagnostic and evaluation before and after treatment and with annual control. For the treatment, self-ligating brackets (Damon technique) were employed. The results: Total correction of Class II condition and overbite was obtained. The desired goals of facial aesthetics and correct function were attained in occlusion and desocclusion, as well as development of the osseous basis and conservation of the canine alveolar cortical height. Conclusion: Through the employment of therapeutic resources available at present and following up the child through his developmental stages, it is possible to combine different treatments to achieve the proposed objectives in a shorter time with excellent results in mesofacial type patients with Class II malocclusion and deep overbite (AU)

El camino del caucho / The way of the rubber

Resumen Las investigaciones de Markham, primero, y luego de Spruce, llevadas a cabo en medio de múltiples peligros, internándose en selvas espesas, vadeando salvajes ríos y enfrentando nativos muchas veces hostiles, permitieron conocer el ciclo de vida del árbol del caucho para el traslado de sus semillas, su aclimatación en Asia y cultivo a nivel industrial. Indudablemente ellos fueron los héroes de esta epopeya al hacer esta investigación venturosa, pero los sabios son modestos y callados, de manera que la gloria se la llevó un empresario decidido y de pocos escrúpulos cual Wickham. En cuanto a Brasil, como buena nación latinoamericana, pecó de ingenuidad, improvisación y negligencia, dejándose arrebatar una inimaginable fortuna: el monopolio del caucho. Creemos que las múltiples aplicaciones médicas del caucho, haciendo menos dolorosos los exámenes y procedimientos, pudieran ser de interés para nuestros colegas.

Investigations first by Markham, and then by Spruce, performed in the middle of multiple risks, in the deep of dense jungle, through the wild rivers and facing up natives many times hostile, brought the knowledge of the life cycle of Hevea brasiliensis, the rubber's tree, necessary for take its seeds to Asia, its adaptation to this continent and its culture at industrial level. Undoubtedly these men were the heroes of this history, but they were wise, modest and quite people, so the glory was for an entrepreneur decided and of scare scruples, like Wickham. And Brazil, as a good Latin American nation, sinned of naivety, improvidence and negligence, allowing itself the lost of an unimaginable fortune: the monopoly of the rubber. Because the many applications of rubber in medical practice, the history of this tree may interest our colleagues.

Interacción de la glucosa con espesantes utilizados en el control de la disfagia orofaríngea / Glucose interaction with thickeners used in dysphagy oropharyngeal control / Interação da glicose com espessantes utilizados no controle da disfagia orofaríngea

La disfagia se define como un trastorno de la deglución caracterizado por una dificultad en la preparación oral del bolo alimenticio o en el desplazamiento del alimento desde la boca hasta al estómago. Se asocia con la cuarta causa de muerte más frecuente en adultos mayores y se identifica como un agente contribuyente a la malnutrición. Los alimentos destinados a las personas que padecen disfagia son preparados con productos que modifican la viscosidad de forma que al ser ingeridos puedan ser más seguros. En el presente trabajo se pretende establecer la interacción entre la glucosa y tres espesantes comerciales de origen vegetal (dos a base de almidón y un tercero constituido por una mezcla de maltdextrina, goma xantana y goma guar) a efectos de identificar el más adecuado para uso en dietas de pacientes con disfagia orofaríngea, en las condiciones ensayadas. Para ello se determina el grado de estabilidad que presentan en función del tiempo de reposo (0, 24 horas) y su comportamiento en el intervalo de temperatura comprendido entre 25 y 50 °C. Se han estudiado concentraciones de espesante hasta el máximo del 6% en combinación con 5 concentraciones de glucosa hasta un máximo de 27%. Se constata la interacción conjunta de la goma xantana, la goma guar y la maltodextrina con la glucosa. Estos espesantes, potencialmente aptos para regular el grado de consistencia de productos alimentarios destinados a la alimentación de pacientes con disfagia orofaríngea, presentan un proceso de hidratación lento que, además, se ve agravado por la interacción de la glucosa.

Dysphagia is defined as a swallowing disorder characterized by a difficulty in the alimentary bolus preparation or in food displacement from the mouth to the stomach. It is the fourth cause of death in adults and it is identified as a malnutrition agent. Food destined to individuals with dysphagia is prepared with products which modify their viscosity to make them safer to swallow. The present job tries to establish an interaction between glucose and three commercial thickeners of vegetal origin (two from starch and a third one made from a mix of maltodextrin, xanthan gum and guar gum in order to identify the most suitable one to be used in diets of patients with oropharyngeal dysphagia on the tested conditions. The stability degree in concordance with the time relation (0-24 hours) and its performance on the gap temperature between 25 and 50 ºC is determined. Tests have been done with thickener concentrations up to a maximum of 6% in combination with 5 glucose concentration up to a maximum of 27%. The common interaction of xanthan gum, guar gum and maltodextrin with glucose is found. Those thickeners potentially suitable to regulate the consistency degree of food products destined to the nourishment of patients with oropharyngeal dysphagia show a slow hydration process which is also aggravated by the glucose interaction.

A disfagia é definida como um distúrbio de deglutição caracterizado por uma dificuldade na preparação do bolo alimentar ou na passagem do alimento da boca até o estômago. Associa-se à quarta causa de morte mais frequente em adultos idosos e é identificada como um agente que contribui à má nutrição. Alimentos destinados a pessoas que sofrem de disfagia são preparados com produtos que modificam a viscosidade de forma que ao serem ingeridos possam ser mais seguros. O presente trabalho visa a estabelecer a interação entre a glicose e três espessantes comerciais de origem vegetal (dois com base de amido e um terceiro feito a partir de uma mistura de maltodextrina, goma xantana e goma guar) a fim de identificar o mais adequado, para ser utilizado em dietas de pacientes com disfagia orofaríngea nas condições testadas. Para isso é determinado o grau de estabilidade que apresenta em função do tempo de repouso (0-24 horas) e seu desempenho no intervalo de temperatura compreendido entre 25 e 50 °C. Concentrações de espessantes foram estudadas até o máximo de 6% em combinação com 5 concentrações de glicose até um máximo de 27%. Pode ser encontrada a interação conjunta da goma xantana, a goma guar e a maltodextrina com a glicose. Estes espessantes, potencialmente adequados para regular o grau de consistência de produtos alimentares destinados à alimentação de pacientes com disfagia orofaríngea, apresentam um processo de hidratação lento que, além disso, é agravado pela interação da glicose.

Evaluation of the inflammatory response induced by different materials in the treatment of perianal fistulas: experimental study in rats / Avaliação da resposta inflamatória produzida por diferentes materiais utilizados como sedenho no tratamento de fístulas perianais: estudo experimental em ratos

The medical literature has no study evaluating the effectiveness of different materials used as setons in the treatment of perianal fistulas; therefore, there is no evidence of availability of a more effective material than others for this purpose. Objective: To evaluate the inflammatory response induced by different materials used as seton in perianal fistulas in rats. Method: Thirty Wistar rats, which were initially submitted for the construction of a perianal fistula by passing transfixing steel wire into the anal canal, were used. The rats were kept for 30 days; after this period, and with confirmation of the formation of the perianal fistula, the setons were introduced (10 rats - cotton thread #0; 10 rats - rubber; and 10 rats - silastic); after 30 days the animals were euthanized, and then the area of the fistula repaired by the seton was resected, and the material retrieved was submitted to histological analysis. The results were analyzed statistically. Results: The mean degree of inflammatory process observed by histological analysis after 30 days was 2.3 for the cotton group; 1 for the rubber group; and 1.2 for the silastic group. Conclusion: A greater inflammatory response was observed in the group treated with a cotton seton. In the remaining groups, a lower inflammatory response, with equal intensity for rubber and silastic-treated rats, was noted.

Não foram encontrados na literatura médica estudos que avaliassem a eficácia dos diferentes materiais utilizados como sedenho no tratamento de fístulas perianais, portanto, não havendo evidências de que haja um material mais eficaz do que outro para esta finalidade. Objetivo: avaliar a resposta inflamatória induzida por diferentes materiais utilizados como sedenhos em fístulas perianais em ratos. Método: foram utilizados 30 ratos Wistar, os quais foram inicialmente submetidos à criação de fístula perianal pela passagem de fio de aço transfixante no canal anal, mantido por 30 dias; após este período, confirmada a formação de fístula perianal, foram introduzidos os sedenhos (10 ratos - fio de algodão zero, 10 ratos - borracha e 10 ratos - silastic); após 30 dias os animais foram submetidos a eutanásia, ressecando-se a área da fístula reparada pelo sedenho, submetendo-se este material à análise histológica. Os resultados foram submetidos a tratamento estatístico. Resultados: a média do grau de processo inflamatório observado pela análise histológica após 30 dias foi de 2,3 para o grupo de sedenho de algodão; de 1 para o grupo de sedenho de borracha e 1,2 para o grupo silastic. Conclusão: Houve maior resposta inflamatória no grupo tratado com sedenho de algodão. Houve resposta inflamatória menor e de igual intensidade nos animais tratados por sedenho de borracha e silastic.

Novel sustained-release of Stryphnodendron obovatum leaves extract using natural rubber latex as carrier

Natural rubber latex biomembranes (NRL), obtained from rubber tree Hevea brasiliensis (Willd. ex A. Juss.) Mull. Arg., have been used as sustained drug release of drugs and plant extracts with medicinal properties. The Stryphnodendron obovatum Bench (Fabaceae), popularly known as "barbatimão" has anti-inflammatory and healing properties already described in literature. Thus, the aim of this work were to study the release behavior of the hydroethanolic extract from the leaves of S. obovatum loaded in the NRL by ultraviolet­visible spectroscopy (UV-VIS). The release followed a biexponential pattern and the mechanism of release was Super Case II (n > 1). FTIR analyses did not show reaction between NRL and extract, only intermolecular interaction. From SEM was possible to observe the extract at the surface, responsible for the initial fast release, which the concentrations at 5.0 mg/mL released 2.4% and at 0.1 mg/mL released 96.8%; both reached the plateau in 7 days.

Influence of different beverages on the force degradation of intermaxillary elastics: an in vitro study

Objective: The aim of this study was to evaluate in vitro the effects of frequently ingested beverages on force degradation of intermaxillary elastics. Material and Methods: One hundred and eighty 1/4-inch intermaxillary elastics (TP Orthodontics) were immersed into six different beverages: (1) Coca-Cola®; (2) Beer; (3) Orange juice; (4) Red wine; (5) Coffee and (6) artificial saliva (control). The period of immersion was 15 min for the first and second cycles and 30 min for the third to fifth cycles. Tensile forces were read in a tensile testing machine before and after the five immersion cycles. One-way repeated measures ANOVA was used to identify significant differences. Results: Force degradation was seen in all evaluated groups and at all observation periods (p<0.05). A greater degree of degradation was present at the initial periods, decreasing gradually over time. However, no statistically significant differences were seen among groups at the same periods, showing that different groups behaved similarly. Conclusion: The chemical nature of the evaluated beverages was not able to influence the degree of force degradation at all observation periods.

Sutura elástica para tratamento de grandes feridas / Elastic sutures for the treatment of extensive wounds

O fechamento de grandes feridas continua sendo um importante desafio para o cirurgião plástico. O objetivo deste artigo é a divulgação da sutura elástica como uma técnica eficaz para o fechamento de grandes feridas. Foram incluídos no estudo 14 pacientes portadores de grandes lesões decorrentes de traumas diversos em membros inferiores. O fechamento completo das feridas foi obtido por procedimento dividido em duas etapas, sendo a primeira representada por aproximação das bordas opostas da ferida por meio de tiras circulares elásticas de borracha e a segunda, realizada alguns dias após, com a retirada das tiras elásticas, seguida de sutura simples com fio mononáilon. A sutura elástica demonstrou ser uma técnica segura, funcionalmente eficaz, de fácil execução e de baixo custo para fechamento de grandes feridas, evitando áreas doadoras, como nos enxertos de pele.

The suture of extensive wounds remains a major challenge for plastic surgeons. The objective of this article is to promote use of elastic sutures as an effective procedure for the closure of extensive wounds. Fourteen patients presenting with extensive wounds caused by trauma in the lower limbs were included in the study. The entire wound was sutured in each patient with a two-step procedure. In the first step, the opposite edges of the wound were approximated using rubber circular elastic bands. In the second step, carried out a few days later, the elastic bands were removed, followed by a simple suture with monofilament nylon thread. Placement of elastic sutures proved to be a safe, functionally effective, easy-to-perform, and low-cost procedure for the closure of extensive wounds without using donor areas as skin grafts.

Biodegradation of a blended starch/natural rubber foam biopolymer and rubber gloves by Streptomyces coelicolor CH13

Background: The growing problem of environmental pollution caused by synthetic plastics has led to the search for alternative materials such as biodegradable plastics. Of the biopolymers presently under development, starch/natural rubber is one promising alternative. Several species of bacteria and fungi are capable of degrading natural rubber and many can degrade starch. Results: Streptomyces coelicolor CH13 was isolated from soil according to its ability to produce translucent halos on a mineral salts medium, MSM, supplemented with natural rubber and to degrade starch. Scanning electron microscope studies showed that it colonized the surfaces of strips of a new starch/natural rubber biopolymer and rubber gloves and caused degradation by forming holes, and surface degradation. Starch was completely removed and polyisoprene chains were broken down to produce aldehyde and/or carbonyl groups. After 6 weeks of cultivation with strips of the polymers in MSM, S. coelicolor CH13 reduced the weight of the starch/NR biopolymer by 92 percent and that of the rubber gloves by 14.3 percent. Conclusions: This study indicated that this bacterium causes the biodegradation of the new biopolymer and natural rubber and confirms that this new biopolymer can be degraded in the environment and would be suitable as a ‘green plastic’ derived from natural sources.

Fundamentos sobre o conhecimento dos aditivos químicos presentes nas luvas de borracha / Fundamentals of the knowledge about chemical additives present in rubber gloves

FUNDAMENTOS: Uma das causas mais frequentes de dermatite de contato alérgica, de origem ocupacional, são os aditivos da borracha, presentes nos Equipamentos de Proteção Individual. Os aditivos das luvas natural e sintética mais alergênicos são tiurams, mercaptos e carbamatos. OBJETIVO: levantar o nível de conhecimento em relação aos aditivos químicos utilizados na fabricação das luvas de borracha sintética. MÉTODOS: Foi aplicado um questionário aberto a profissionais que trabalham com fabricação, pesquisa, prescrição e comercialização das luvas. Foi adotado o método de pesquisa qualitativa. RESULTADOS: Foram entrevistadas 30 pessoas: 4 pesquisadores na área de Medicina do Trabalho, 5 médicos do Trabalho, 2 técnicos de segurança do Trabalho, 1 médico do sindicato de trabalhadores da borracha, 1 engenheiro de Segurança do Trabalho, 1 engenheira de Produção do setor de fabricação de luvas de borracha, 4 empresários importadores de luvas, 1 empresário fabricante de luvas, 3 empresários que comercializavam Equipamentos de Proteção Individual, 3 vendedores de lojas de Equipamentos de Proteção Individual, 2 empresários de lojas que comercializavam produtos para alérgicos e 3 dermatologistas. CONCLUSÃO: O conhecimento da composição química das luvas é pequeno. A rotulagem das luvas, com a descrição da composição química, facilitaria a escolha do melhor tipo de luva para cada pessoa. Esta ação, de baixo custo para as empresas, seria um ganho, do ponto de vista da saúde pública, e teria grande repercussão nos usuários de luvas de borracha.

BACKGROUNDS: One of the most frequent causes of allergic contact dermatitis of occupational origin are rubber additives, which are present in Personal Protective Equipment (PPE). The most allergenic additives of natural and synthetic gloves are thiurams, carbamates and mercapto group. OBJECTIVE: To investigate the state of knowledge about the chemical additives used in the manufacture of synthetic rubber gloves. METHODS: This was a qualitative research study in which professionals working in the manufacture, research, prescription and commercialization of gloves answered an open questionnaire. RESULTS: 30 individuals were interviewed: 4 researchers in occupational medicine, 5 occupational physicians, 2 occupational safety technicians, a rubber workers' union physician, an occupational safety engineer, a pro duction engineer of rubber gloves, 4 importers of gloves, a manufacturer of gloves, 3 businessmen who sell PPE, 3 salesclerks working in stores that sell PPE, 2 businessmen who own stores that sell products for allergic indivi duals, and 3 dermatologists. CONCLUSION: Knowledge of the chemical composition of rubber gloves is scant. The labeling of gloves, with the description of their chemical composition, would facilitate choosing the best type of glove for each person. This low-cost action to businesses would be a gain from the standpoint of public health, with huge repercussions for users of rubber gloves.

Trajetória e memórias sobre a saúde de soldados da borracha em seringais do Acre / Trajectories and memories of rubber soldiers health in rubber tree extraction in Acre

O Acre testemunhou dois momentos históricos fundamentais para a sua colonização, ambos relacionados à extração da borracha, sendo o segundo patrocinado pelos Estados Unidos da América que, na Segunda Guerra Mundial, através dos Acordos de Washington, encontrou, no Brasil, a fonte do látex, matéria prima necessária para a produção bélica, uma vez que a Malásia, fornecedora, até então, não mais o fazia por imposição do governo japonês, que tomou seus campos de produção. Esse processo migratório campanhista levou aos seringais amazônicos, no início da década de 40 do século passado, mais de 75 mil jovens, que trocaram a seca do sertão nordestino pela úmida e tropical Floresta Amazônica, enfrentando dificuldades de adaptação dramáticas, atestadas pela morte de cerca de 25 mil Soldados da Borracha, ao final da guerra. O objetivo foi o de resgatar as memórias e histórias sobre o cuidado da saúde desses brasileiros que foram submetidos a vulnerabilidades e traumas culturais, sociais, familiares e de saúde, em prol de acordo que rendeu ao governo brasileiro pouco mais que o Banco da Amazônia e a Usina de Aço de Volta Redonda (RJ). O estudo foi quali-quantitativo, através de entrevistas, gravadas e transcritas, de trabalhadores procedentes do Nordeste que atuaram nos seringais da Amazônia, e que migraram para a capital do Acre, Rio Branco, entre as décadas de 40 e 60. Para análise das entrevistas foi utilizada a técnica do Discurso do Sujeito Coletivo,por meio do programa QualiQuantiSoft®. Os relatos mostraram situações de desamparo e descreveram a luta pela sobrevivência diante das adversidades desses homens e mulheres que, se hoje estão disponíveis para relatar esses fatos, provavelmente ainda o fazem por terem se transformado, em algum momento logo após a chegada, em amazônidas.

Evaluation of the in vitro biocompatibility of orthodontic elastics

Aim: Latex has been extensively used in orthodontics since the advent of the specialty. Natural latex does not fall into the category of materials known to be entirely inoffensive. The objective of the present in vitro study is to test the hypothesis that there is no difference in the cytotoxicity between natural latex elastics of different colors. Methods: The present article compared different latex intra-oral elastics (5/16 = 7.9 mm, mean load). The samples were divided into six groups of 15 elastics according to their manufacturer: Groups N, Y, V, R, G and P (Uniden, natural latex elastics and colored elastics, namely, yellow, violet, red, green and pink, respectively).Cytotoxicity assays were performed by using cell culture medium containing cells from mouse fibroblast cell line L929. The cytotoxicity was evaluated by using the “dye-uptake” test, which was employed at two different moments (1 and 24 h). Data were compared by ANOVA and Tukey’s test (P < 0.05). Results: There was statisticallysignificant difference (P < 0.05) between the groups N, Y, V, R, G, P and the cell control at 1 h. After 24 h, a decrease in cell viability was observed in all groups. There was statistically significant difference (P < 0.05) between all test elastics groups and the cell control at 24 h. No statistically significant difference (P >0.05) was found among the test elastics groups at 24 h. Conclusion: Latex elastics from natural, yellow, violet and red colors induced a lowest amount of cell lysis compared to the elastics green and pink colors at 1 h, all latex elastics were found to be highly cytotoxic, regardless of their color at 24 h.

Associação de urticária de contato e dermatite alérgica de contato à borracha / Association of contact urticaria and allergic contact dermatitis to rubber

Apresenta-se o caso de uma profissional da área da saúde que desenvolveu reação de hipersensibilidade dos tipos I e IV à borracha. O quadro clínico mostrava dermatite eczematosa no dorso das mãos. O teste de contato foi positivo para o grupo tiuram, assim como o teste aberto com fragmento de luva após exposição de 20 minutos. A dosagem de IgE sérica (Rast) mostrou-se relevante. As reações aos alérgenos da borracha são frequentes entre os profissionais da saúde, devido ao contato constante com esse material.

We present a case of a healthcare professional that developed type I and IV hypersensitivity reactions to rubber. During the clinical examination the patient showed eczematous dermatitis of the hands. The patch test was positive for thiuram group and an open test with a piece of glove was positive after 20 minutes of exposure. Allergen-specific IgE test (RAST) was relevant. Reactions to rubber allergens are frequent among healthcare professionals due to constant contact with this material.

Planta piloto de um processo eletrolítico em indústria de aditivos para borracha / Pilot plant of an electrolytic process in a rubber additive industry

O efluente de uma indústria produtora de aditivos para borracha foi submetido a um tratamento eletrolítico em vários tempos de eletrólises objetivando principalmente a diminuição da cor do efluente industrial e melhora nos parâmetros preconizados pela legislação brasileira de águas. O tratamento eletrolítico foi construído em uma planta piloto logo após o tratamento físico-químico e biológico realizado pela indústria química. O efluente, após passar pelo tratamento convencional da empresa, apresentou cor marrom e bastante turva, 1592 mg/L de demanda química de oxigênio (DQO), 873 mg/L de demanda bioquímica de oxigênio (DBO) e 1,30 mg/L de ferro solúvel. Após 60 min de eletrólise, este efluente estava incolor, possuía 1004 mg/L de DQO, 593 mg/L de DBO e 0,66 mg/L de ferro solúvel...

Color and characterization of an industry effluent was studied through electrolytic process at various times, before and after it has passed by the treatment process of the industry. A pilot system for electrolyte treatment was installed in the final effluent. After the electrolysis, it was examined for color and the other parameters of the Brazilian regulations (Article 18, CONAMA 357). The non-electrolysed effluent had brown color and rather cloudy, 1592 mg/L of COD, 873 mg/L of BOD, 1.30 mg/L of soluble iron. After 60 minutes of electrolysis, the effluent was colorless, had 1004 mg/Lof COD, 593 mg/L of BOD and 0.66 mg/L of soluble iron. The electrolyzed effluent could be used again by the industry reducing the use of tap water...

Selection of sulfur oxidizing bacterium for sulfide removal in sulfate rich wastewater to enhance biogas production

Sulfur oxidizing bacteria (SOB) were isolated and tested in order to remove sulfide from high sulfate wastewater to reduce the amount of hydrogen sulfide (H2S) in the produced biogas. A promising SOB isolate, designated as isolate T307, was selected due to its best sulfide removal (86.7 percent) in the effluent of a sulfate reduction reactor (SRR) over a 24 hrs incubation. The bacterium was able to grow better as a mixotroph (yeast extract as a carbon source) than as a chemolithoautotroph. In addition, as a heterotroph, the bacterium grew well with yeast extract and peptone. Based on partial 16S rRNA gene sequence, the isolated T307 was an Alcaligenes sp. and was able to convert most of sulfide species (total sulfide: TS; dissolved sulfide: DS and H2S) into elemental sulfur or sulfate over a 20 hrs period of cultivation by controlling the speed of shaking. In a biogas reactor set, after pre-treating a sulfide medium with Alcaligenes sp. T307 there was a much higher specific yield of CH4 (238 ml CH4 g-1COD removed) and more biogas (154 ml L-1 d-1) was produced with the biogas containing more methane (48.1 percent CH4, 51.5 percent CO2 and 0.41 percent H2S) in comparison to a control with a specific yield of CH4, (72 ml CH4 g-1COD removed) 86 ml L-1 d-1 biogas produced with a composition of 35.5 percent CH4, 63.7 percent CO2 and 0.86 percent H2S.