Estudio del efecto citotóxico e irritativo de jabones para la limpieza cutánea / Study of the cytotoxic and irritant effects of skin cleansing soaps

Resumen Introducción: El jabón para el aseo cutáneo es de empleo común entre la población, sin embargo, es posible que cause daño a las células de la piel y modifique la barrera cutánea. Objetivo: Determinar el efecto citotóxico de los jabones en queratinocitos cultivados in vitro y correlacionarlo con la irritación clínica. Método: Se realizó una encuesta para conocer los jabones comerciales más utilizados y su cantidad; posteriormente, se evaluó su citotoxicidad en cultivos de queratinocitos humanos mediante el método de resazurina. Los jabones con mayor y menor citotoxicidad se aplicaron en piel de voluntarios sanos para evaluar su efecto en la barrera cutánea mediante ensayos de colorimetría y pérdida transepidérmica de agua. Resultados: De los jabones analizados, 37 % demostró ser tóxico para los queratinocitos in vitro. El jabón con mayor toxicidad indujo el mayor índice de eritema y pérdida transepidérmica de agua, en comparación con el jabón menos tóxico y el vehículo empleado como solución control. Conclusión: Los jabones comercializados para el aseo cutáneo pueden incluir ingredientes químicos que dañan los queratinocitos humanos y causan irritación subclínica de la barrera cutánea. Su utilización puede agravar dermatosis preexistentes, generar dermatitis xerósica o de contacto irritativa y causar atrofia y dermatoporosis.

Abstract Introduction: The use of soap for skin cleansing is common among the population. However, it is possible that it causes damage to skin cells and disrupts the skin barrier. Objective: To determine the cytotoxic effect of soaps on in vitro-cultured keratinocytes and to correlate it with clinical irritation. Method: A survey was conducted to find out the most widely used commercial soaps and their number. Subsequently, their cytotoxicity was evaluated in human keratinocyte cultures using the resazurin assay. The soaps with the highest and lowest cytotoxicity were applied to the skin of healthy volunteers to assess their effect on the skin barrier using colorimetry and transepidermal water loss (TEWL) assays. Results: Of the analyzed soaps, 37 % were shown to be toxic to keratinocytes in vitro. The soap with the highest toxicity induced the highest rate of erythema and TEWL, in comparison with the least toxic soap and the vehicle used as the control solution. Conclusion: Soaps marketed for skin cleansing can contain chemical ingredients that damage human keratinocytes and cause skin barrier subclinical irritation. Their use can worsen preexisting dermatoses, generate xerotic or irritant contact dermatitis, and cause atrophy and dermatoporosis.

Dermatitis de los bañistas asociada al contacto con la medusa -liriope tetraphylla- en Monte Hermoso, Buenos Aires, Argentina / Sea bathers' dermatitis caused by contact with the medusa -liriope tetraphylla- in Monte Hermoso beach, Buenos Aires, Argentina

Desde el año 2013 es frecuente encontrar a la medusa Liriope tetraphylla en las costas de Monte Hermoso y zonas aledañas de la Provincia de Buenos Aires. En los últimos años se ha podido registrar un número importante de afectados por picaduras de Liriope tetraphylla. Cuando las picaduras son abundantes producen el fenómeno de "tapioca" o "pica- pica", provocando en forma inmediata ardor leve y luego lesiones pápulo-eritema-edematosas con picazón intensa. Las lesiones tienen una distribución específica en zonas de flexión corporal y lugares cubiertos por el traje de baño. El día 15 de febrero de 2015 se registró un "bloom" de L. tetraphylla, con una densidad de 605 individuos/m3, que se vio reflejado en el gran número de personas afectadas que ingresaron el Servicio de Emergencias del Hospital Municipal de Monte Hermoso "Dr. Ramón Carrillo" el día 16 de febrero de 2015. De un número total de 71 pacientes adultos que ingresaron ese día al Servicio, fueron atendidos por dermatitis asociada al contacto con "tapioca" 19 de ellos (26.80%),y de un total de 69 pacientes pediátricos, 49 de ellos (71%) fueron tratados por la misma afección. En el presente trabajo se detallan los síntomas causados por "tapioca" en base a 68 casos tratados. Se describe el tratamiento utilizado y métodos de prevención para las lesiones, así como su relación con el bloom de la especie de aguaviva en cuestión.

Since the summer of 2013 the sea medusa Liriope tetraphylla was found frequently on the shores of Monte Hermoso and nearby beaches in Buenos Aires Province. Recently, there has been a significant number of sea bathers affected by Liriope tetraphylla bites. When the bites are numerous, a phenomenon called "tapioca" or "pica - pica" occurs, thus causing immediate mild burning followed by erythematous-edematous papulas and intense itching. Lesions have a specific distribution in body flexion parts and body areas covered by the bathing suit. In February 15, 2015 there was a L. tetraphylla bloom, recording a density of 605 individuals/m3, that caused a large number of sea bathers to present dermatitis and receive treatment at the Emergency Service of Dr. Ramón Carrillo Hospital in Monte Hermoso. On this day, 19 out of 71 adults (26.80%) and 49 out of 69 children (71%) who were treated at the Emergency Service showed clinical profiles compatible with the contact with the sea medusa. In this work, the symptoms caused by "tapioca" based on 68 cases are described in detail, as well as the medical treatment applied, the preventive methods for medusa bites, and the relation with the medusa bloom.

Desenvolvimento de epiderme humana reconstruída (RHE) como plataforma de testes in vitro para irritação, sensibilização, dermatite atópica e fotoimunossupressão / Development of a Reconstructed Human Epidermis (RHE) as platform to in vitro assays: irritation, sensitization, atopic dermatitis and photoimmunosuppression

O desenvolvimento de novos modelos de pele e novas metodologias in vitro segue uma tendência mundial na busca pela redução ou substituição de testes em animais. Nesse contexto, kits de epiderme humana reconstruída (RHE) apresentam-se como uma plataforma promissoras para essa proposta e, alguns modelos encontram-se validados para ensaios de irritação e corrosão cutânea in vitro. Entretanto, em países como o Brasil, enfrentam-se questões alfandegárias e perda do material por perecibilidade, dificultando e até impedindo, a importação desses kits para utilização por parte das indústrias e laboratórios nacionais. Em contrapartida, o desenvolvimento de um modelo de RHE apresenta-se como um avanço tecnológico e ganho de autonomia para esses países. Assim, no capítulo 1 explorou-se o desenvolvimento de um modelo nacional de RHE (USP-RHE) que atendesse às exigências internacionais descritas no guia OECD 439. O modelo desenvolvido apresentou uma epiderme bem diferenciada e atendeu aos parâmetros de qualidade (histologia, viabilidade e função barreira) bem como da funcionalidade, a qual é expressa na capacidade de distinção entre irritantes e não irritantes, apresentando 85,7% de especificidade, 100% sensibilidade e 92,3% de acurácia quando comparada com a classificação in vivo obtida pelo ensaio do linfonodo local (LLNA). No capítulo 2, células monocíticas THP-1 em monocamada foram capazes de distinguir entre agentes sensibilizantes e não sensibilizantes por meio da expressão de CD86, CD54 e liberação de IL-8. Após a obtenção de RHE e THP-1 funcionais, um cross-talking foi estabelecido gerando uma RHE imunocompetente. A RHEI distinguiu satisfatoriamente entre agentes sensibilizantes e não sensibilizantes por meio da expressão de CD86 e CD54 na membrana das células THP-1. A liberação de IL-8 também foi avaliada na RHEI, mas, não demonstrou ser um bom indicador para a avaliação de sensibilização, ao contrário de IL-1α, que distinguiu satisfatoriamente agentes sensibilizantes de não-sensibilizantes, mas não foi capaz de hierarquizá-los. No capítulo 3, avaliou-se o papel de interleucinas do tipo Th2 e da depleção de colesterol na membrana plasmática no desenvolvimento de características morfológicas e moleculares da dermatite atópica (DA) in vitro em um modelo de RHE. Os resultados demonstram que o uso de IL-4, IL-13 e IL-25 em combinação com a depleção de colesterol na membrana plasmática mimetiza in vitro, as principais características da DA. No capítulo 4, buscou-se avaliar os efeitos imunossupressores da radiação ultravioleta na RHEI. Os ensaios foram realizados em diferentes períodos de exposição, entretanto, não foi possível observar tais efeitos. Os resultados justificam-se pela ausência da liberação de IL-10 pelo RHE imunocompetente, por exemplo, e demonstram uma limitação do RHE imunocompetente para avaliações de inativação da reposta imune. Neste trabalho, concluímos que foi possível obter uma RHE competitiva, similar aos modelos internacionais validados e que pode ser utilizada como plataforma para ensaios de irritação e sensibilização cutânea, além de ser uma plataforma para estudos da dermatite atópica. No modelo é possível estudar a ativação do sistema imune, o que o torna promissor como uma plataforma para avaliação de resposta imunológica in vitro. Conclui-se, portanto, que os objetivos foram amplamente atendidos além de oferecermos um protocolo de livre acesso para reprodução por outros laboratórios e um modelo para validação futura

The development of new in vitro skin models and new methodologies follows a global trend in search for reductions or replacement of animal testing. In this context, Reconstructed Human Epidermis kits (RHE) are presented as a promising platform in the search for alternative methods to animal use, and some models are validated for skin irritation and corrosion in vitro tests. However, in countries such as Brazil, who face customs issues and loss of material due to perishability, making it challenging and even compromising the importation of these kits for use by industries and laboratories. In contrast, the development of an RHE model is presented as a technological breakthrough and gain of autonomy for these countries. Thus, in Chapter 1 we explored the development of a national model of RHE (USP-RHE) that meet international requirements described in OECD TG 439. The developed model presented a well-differentiated epidermis and met the quality parameters, for instance, histology, viability, and barrier function as well as the functionality expressed in the capacity of screening between irritants and nonirritants, with 85.7 % of specificity, 100 % of sensitivity and 91.7% of accuracy in comparision to in vivo UN GHS classification from Local limph node assay (LLNA). In chapter 2, monocytic THP-1 cell line, as monolayers, were able to distinguish between sensitizers and non-sensitizers by expression of CD86, CD54, and IL-8 release. In this model, functional RHE and THP-1 were used in a cross-talking, and thus an immunocompetent RHE (RHEI) was generated. The RHEI has distinguished satisfactorily between sensitizers and non-sensitizers through CD86 and CD54 expression that was larger and more sensitive in this model. The release of IL-8 was also evaluated in RHEI, however, did not demonstrate to be a good parameter for this evaluation, unlike IL-1α, which satisfactorily distinguished sensitizers from non-sensitizers, but was not able to hierarchize them. In chapter 3, we evaluated the role of Th2-related cytokines and plasma membrane cholesterol depletion (CD) in the development of atopic dermatitis (AD) morphological and molecular characteristics in an in vitro model of RHE. The results showed that combination of IL-4, IL-13 and IL-25 in combination with CD can reproduce the major features of AD in vitro. In Chapter 4, we sought to evaluate the ultraviolet radiation-induced immunosuppressive effects in RHE. The tests were performed at different times. However, it was not possible to observe such effects. The results are justified by the absence of IL-10 release by RHEI, for example, and show a limitation of RHEI for rating inactivation of the immune response. In this work, we conclude that it was possible to obtain a competitive RHE similar to the validated international models that can be used as a platform for irritation and skin sensitization tests, besides being a platform for the study of atopic dermatitis. Using this model is possible to explore the activation of immune system, which makes it promising as a platform for the evaluation of immune response in vitro. We conclude, therefore, that the objectives have been met as well as it is offering an open source protocol for breeding by other laboratories, thus offering the RHE model developed here for future validation tests

Bioanálisis predictivo de tolerancia dérmica de cosméticos para bebés in vivo / Predictive bioanalysis of skin tolerance of cosmetics for babies in vivo

Objetivo: prever el riesgo potencial de irritabilidad dérmica de una crema y una loción para bebés, con el fin de obtener el registro sanitario y disminuir la eventualidad de riesgo para la salud. Métodos: se realizó el bioanálisis predictivo de tolerancia dérmica in vivo en conejos, a través de un estudio de tipo exploratorio clínico cualitativo e histopatológico, basado en el enfoque de la ley del Arte para explicar el riesgo/efectividad comparable en humanos. Se aplicó la técnica de exposición aguda simple (prueba parche oclusivo) en seis conejos, por cada producto. Se estimaron los efectos dérmicos mediante una escala de valores que define la probabilidad de inseguridad atribuible por la exposición al cosmético, según prueba de toxicidad dérmica de la Organización para la Cooperación Económica y Desarrollo 2004 (OCED), con ciertas modificaciones por los autores. Resultados: en el bioanálisis se encontró cierta irritabilidad dérmica en la piel de los conejos al aplicarles el cosmético en una dosis única por 92 días. El estudio clínico se complementó con el análisis histopatológico de una muestra de piel irritada y no mostró cambios significativos a los observados. Conclusiones: el bioanálisis clínico e histopatológico permite inferir una irritabilidad dérmica entre insignificante y leve, lo que sugiere la necesidad de mejorar la formulación de los cosméticos estudiados para obtener el registro sanitario, y así alertar tempranamente al productor y a la comunidad de la seguridad y eficacia de los productos(AU)

Objective: to prevent the potential risk of dermal irritability from a cream and a lotion for babies, in order to obtain health registration and to reduce possible health risks. Methods: in vivo predictive bioanalysis of dermal tolerance carried out in rabbits through a qualitative and histopathological clinical exploratory-type study, based on the Lex Artis approach to explain the comparable risk/effectiveness in humans. There was applied the single acute exposure technique (occlusive patch test) in six rabbits to test each product. Dermal effects were then measured in a value scale defining the cosmetic exposure-attributed unsafeness probabilities, according to the dermal toxicity test of the Organization for Economic Cooperation and Development, with some modifications by the authors. Results: the bioanalysis found some dermal irritability in the rabbits' skin after using the single dose of cosmetic for 92 days. The clinical study was supplemented with the histopathological analysis of a sample of irritated skin, without significant changes other than those observed. Conclusions: the clinical and hisopathological analysis showed mild to negligible dermal irritability, which indicates the need for improvements to the formulation of the studied cosmetics in order to obtain the health registration and thus to early advise the manufacturer and the community about the safety and efficacy of products(AU)

Usos y abusos de los gases lacrimógenos y la salud: prevención y manejo / Uses and abuses of teargas and health: prevention and management

Los gases lacrimógenos (GL) son métodos de control de manifestaciones públicas por los órganos represivos, muy utilizados y efectivos globalmente. El objetivo de esta revisión es actualizar información técnica sobre los gases lacrimógenos, añadiendo aspectos más recientes legales, éticos, médicos y preventivos del uso y abuso de estos agentes químicos durante las acciones de las fuerzas policiales y represivas. Las fuentes de información secundarias seleccionadas son portales generales con el buscador Google, académicos (Google académico), PubMed y de las organizaciones gubernamentales y no gubernamentales, también se incluyen hemerotecas de artículos periodísticos sobre su uso desde 2000 hasta 2014. La exposición aguda a (GL) se expresa con manifestaciones clínicas de afección respiratoria, irritación de los ojos y de la piel, requiriendo en la mayoría de los casos medidas generales de atención fuera del hospital. Sin embargo, en casos de personas con co-morbilidades respiratorias, alérgicas, glaucoma y del corazón, acarrean mayores consecuencias que requieren atención médica y hospitalaria. Se han reportado fatalidades relacionadas al uso y abuso de los agentes químicos. Desde el punto de vista de salud pública existe controversia sobre su uso, y definitivamente causan consternación en los afectados y los abusos de su utilización en manifestaciones pacíficas. Se hace un listado de recomendaciones ante exposiciones durante manifestaciones, como prevenir intoxicaciones severas y dar los primeros auxilios...

Tear gases (TG) are methods for public control used by police forces. The objective of this review is to update technical information about tear gas, adding more recent legal, ethical, medical and preventive aspects of the use and abuse of these chemicals during the actions of the police and repressive forces. Selected secondary sources of information are Google, Academic Google, PubMed and of governmental and non-governmental organizations, also included are newspaper archives about its use from 2000 to 2014. Acute exposure to (GL) is expressed with clinical manifestations of respiratory conditions, irritation of the eyes and skin, requiring in most cases general ambulatory measures of care. However, in persons with respiratory, allergic, glaucoma and heart comorbidities, they carry greater consequences requiring hospital care. Fatalities have been reported related to the use and abuse of chemical agents. From the viewpoint of public health there is a controversy about its use, and definitely cause consternation in the affected in peaceful demonstrations. A list of recommendations is made about how to prevent severe intoxications and give first aid...

Skin irritation and sensitization of swine acellular dermal matrix treated with hyaluronic acid / 中华烧伤杂志

<p><b>OBJECTIVE</b>To evaluate the skin irritation and sensitization potential of the swine acellular dermal matrix treated with hyaluronic acid (SADM-HA).</p><p><b>METHODS</b>(1) Skin irritation test. Twelve New Zealand rabbits were divided into SADM-HA group, allogeneic skin group, and (human) xeno-skin group according to the random number table, with 4 rabbits in each group. Four test sites were designed on the back of each rabbit. Two test sites of each rabbit in the three groups were covered with SADM-HA, allogeneic skin, and xeno-skin, respectively. Another test site was covered with gauze containing 200 g/L sodium dodecyl sulfate solution as positive control. The last test site was covered with gauze containing normal saline as negative control. The primary irritation index and cumulative irritation index of each material were calculated. (2) Skin closed-patch test. Sixty guinea pigs were used. Fifty-four guinea pigs were divided into SADM-HA group, allogeneic skin group, and (human) xeno-skin group according to the random number table, with 18 guinea pigs in each group. Twelve guinea pigs in each of the three groups were correspondingly induced and stimulated by SADM-HA, allogeneic skin, and xeno-skin, with 6 guinea pigs in each group treated with ethanol-soaked gauze to serve as negative control. The remaining 6 guinea pigs were treated with gauze containing 25% α-hexylcinnamaldehyde ethanol solution as positive control. The rating scales of Magnusson and Kligman were used to grade the condition of skin after being treated with above-mentioned materials to evaluate skin sensitivity to them at post stimulation hour 24 and 48. Data were processed with the non-parametric test of independent samples.</p><p><b>RESULTS</b>(1) In the skin irritation test, the primary irritation indexes of the three dressings in SADM-HA group, allogeneic skin group, and xeno-skin group were respectively -0.04, 0.13, and 0.08. The cumulative irritation indexes of the three dressings in SADM-HA group, allogeneic skin group, and xeno-skin group were respectively 0.27, 0.10, and 0.25, which were close to those of negative control within the three groups. The skin irritation of each of the three materials was negligible. (2) In the skin closed-patch test, all scores of the three dressings in SADM-HA group, allogeneic skin group, and xeno-skin group were between 0 and 1. The scores of SADM-HA group and allogeneic skin group were close to those of negative control within the two groups (with U values respectively 188.00 and 90.00, P values both above 0.05). The differences were statistically significant between each material of the three groups and positive control (with U values respectively 19.00, 59.00, 21.50, P values all below 0.01).</p><p><b>CONCLUSIONS</b>The SADM-HA is safe and reliable without skin irritation and sensitization, and it has encouraging prospect in clinical application.</p>

Controle de qualidade e análise sensorial em voluntários de xampu esfoliante com extrato hidroalcoólico de Capsicum frutescens L. (Solanaceae) / Quality control and sensory acceptability of exfoliating shampoo containing hydroethanolic extract of Capsicum frutescens L. (Solanaceae) peppers.

A fitocosmética é um setor em nítido crescimento por se ter verificado reais vantagens na incorporação de produtos vegetais em relação a certos produtos sintéticos em produtos cosméticos. O proposto trabalho foi desenvolvido enfocando-se o uso de xampu com a utilização de microesferas de biopolímero e extrato hidroalcoólico de Capsicum frutescens L., mais popularmente conhecida como pimenta-malagueta, para o tratamento de queda capilar simples (alopecia androgênica). As análises físico-químicas envolveram determinação de cinzas totais, pH, identificação de capsaicina e densidade do xampu, entre outros. Considerando-se os diversos aspectos exigidos para a garantia da qualidade do material botânico, que englobam não somente os aspectos físico-químicos, mas também o microbiológico, realizou-se, tanto no extrato quanto no produto final, a contagem total de micro-organismos, pesquisa de Salmonella sp e Escherichia coli, Staphylococcus aureus e Pseudomonas aeruginosa. Foram realizadas análises sensoriais em voluntários, visando avaliar a qualidade sensorial do produto. Os voluntários avaliaram a amostra segundo questionário aplicado. Para as propriedades avaliadas, as microesferas esfoliantes incorporadas ao xampu mostraram-se ser bem aceitas pelos voluntários, principalmente devido à sensação transmitida pela esfoliação, fazendo com que o extrato hidroalcoólico promova uma maior oxigenação local.

Phytocosmetics is a sector of the market in rapid growth, since real advantages have been demonstrated in the incorporation of plant products in cosmetics, in place of certain synthetic products. The focus of this study was on the use of shampoo containing microspheres of biopolymer and a hydroalcoholic extract of the fruit of Capsicum frutescens L., more commonly known as chili pepper, for the treatment of hair loss (androgenic alopecia). The physical and chemical analysis included the determination of total ash, pH and density of the shampoo and the identification of capsaicin. Considering the various requirements for quality assurance of the plant material, encompassing not only physicochemical but also microbiological criteria, both the extract and the final product were subjected to a total count of microorganisms and tests for Salmonella sp, Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa. The sensory quality of the product was assessed by a panel of volunteers, who rated the sample of shampoo in response to a questionnaire. For the properties assessed, the exfoliating microspheres incorporated into the shampoo proved to be well tolerated by the volunteers, mainly on account of the feeling conveyed by exfoliation, causing the hydroalcoholic extract to promote greater local oxygenation.

The relationship between cancer and allergy

OBJECTIVE: Review the literature on the relationship between cancer and allergy. METHOD: Study articles indexed in the databases of PubMed, Lilacs, Bireme and Scielo to verify whether there is a relationship among cancer, allergy, allergy skin tests and serum levels of immune markers. RESULTS: Several studies have suggested an inverse association between allergy and cancer, while others have found no relationship between these entities, while still other authors have shown an increased risk of some cancers in allergic patients. The conflicting findings in previous studies are due in part to the method used, such as different definitions and measures for atopy, as well as variations in the control of confounding factors such as smoking and obesity. It is noteworthy that most of the studies were conducted in several countries and with different parameters. CONCLUSION: There is a lower incidence of allergy in patients with cancer, especially colorectal, pancreatic, and glioma.

Introduce a new vitro replacement method of skin irritation test / 中国医疗器械杂志

A series of new replacement methods of skin irritation test such as EpiSkin, EpiDermSIT (updated) and SkinEthicRHE have been validated by ECVAM. Due to it, animals are protected to the full extent. These provide more methods for biological evaluation of medical devices.

Corrositex®, BCOP and HET-CAM as alternative methods to animal experimentation / Corrositex®, BCOP e HET-CAM como métodos alternativos à experimentação animal

Tests in animals are used as models in toxicological and investigative studies. However, such tests have been considered inhumane because they can cause pain and suffering to experimental animals, while these methods can often be subjective. Protests calling for animal protection have questioned the effectiveness of in vivo tests and suggest the introduction of alternative, in vitro methods. International organizations, such as the Interagency Coordinating Committee on the Validation of Alternative Methods (ICCVAM), the National Institute of Health (NIH), the Organization for Economic Co-operation and Development (OECD), that regulate and develop new alternative animal models, have indicated the running of preliminary assays and execution of sequential tests, which consider physical-chemical properties and data of in vitro assays, before performing in vivo studies. Towards this background, the objective of the present article was to select promising alternative methods such as Corrositex®, BCOP and HET-CAM, intended to refine or replace the use of animals and reduce their suffering.

Testes em animais são utilizados como modelos em estudos toxicológicos e de pesquisa. Entretanto, tais testes têm sido considerados desumanos, porque causam dor e sofrimento aos animais experimentais, porquanto estes métodos podem, freqüentemente, ser subjetivos. Protestos clamando pela proteção animal têm questionado a eficácia dos testes in vivo e sugerem a introdução de métodos alternativos in vitro. Organizações internacionais, tais como Comitê de Coordenação Interagências de Métodos de Validação Alternativos (ICCVAM), Instituto Nacional de Saúde (NIH), Organização para Cooperação Econômica e Desenvolvimento (OECD), que regulam e desenvolvem novos métodos alternativos aos modelos animais, indicaram a realização de ensaios preliminares e a execução de testes seqüenciais, que consideram as propriedades físico-químicas e os dados dos ensaios in vitro, antes de efetuarem estudos in vivo. Nessa direção, o objetivo do presente artigo foi selecionar métodos alternativos promissores, tais como Corrositex®, BCOP e HET-CAM, com o intuito de aperfeiçoar ou substituir o uso de animais e reduzir seus sofrimento.

Implementation of a penicillin allergy skin test / Implementação de um teste cutâneo de alergia à penicilina

The penicillin allergy skin testing is the only accurate and reliable test for penicillin hypersensitivity mediated by IgE. It is useful for identifying patients with doubtful history of allergy. Positive test for major and minor determinants presents a positive predictive value of 50 percent and negative predictive value of 99 percent. In Brazil, the Ministry of Health suggests a protocol for in house made reagents, since they are not commercially available. As the referred protocol does not mention some important details about the test procedures, we propose in the present work to implement them, critically evaluating each step in order to allow the protocol establishment at any health service, with quality and safety.

O teste cutâneo para alergia imediata a penicilina é o único teste validado internacionalmente, sendo que sua grande utilidade reside na avaliação de pacientes com história positiva de alergia a penicilina. O teste positivo para determinantes principais e secundários da penicilina apresenta um valor preditivo positivo de 50 por cento e valor preditivo negativo de 99 por cento. Em nosso meio, o Ministério de Saúde disponibiliza um protocolo para o preparo dos reagentes, uma vez que os mesmos não estão disponíveis comercialmente. Como o referido protocolo não apresenta maiores detalhes sobre o cuidado relativo às etapas de preparo das soluções, bem como faltam algumas considerações no que tange a realização do teste, propusemo-nos no presente trabalho operacionalizar o teste, avaliando de forma crítica e minuciosa cada etapa, de forma que outros profissionais possam reproduzi-lo de maneira mais segura e eficaz.

Changes of nitric oxide after trichloroethylene irritation in hairless mice skin and protection of ginkgo biloba extract and vitamin E / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To study the changes of nitric oxide (NO) in the BALB/c hairless mice skin after trichloroethylene (TCE) irritation and the protection of ginkgo biloba extract (GbE) and vitamin E (VE).</p><p><b>METHODS</b>132 BALB/c hairless mice were randomly divided into blank control group, solvent group (olive oil), TCE groups (20%TCE, 40%TCE, 80%TCE and 100%TCE), GbE groups (0.1%GbE, 1%GbE and 10%GbE) and VE groups (5%VE, 10% VE and 20% VE), with 11 animals in each group, 5 for acute irritation test and 6 for the cumulative irritation test. The skin irritation was observed, and the levels of NO in the dorsal skin of BALB/C hairless mice were detected. The kit of NO was used to detect the levels of NO in the dorsal skin of BALB/c hairless mice.</p><p><b>RESULTS</b>(1) The skin presented erythema and edema after TCE irritation both in acute irritation and cumulative irritation test and the skin inflammation showed time-dose effect relationship; the mice skin was protected in GbE or VE groups. (2) In the acute stimulation test, the levels of NO in 80%TCE group (69.895 +/- 9.605 micromol/mg pro) and 100%TCE group (77.273 +/- 9.290 micromol/mg pro) were significantly different compared with blank control group and solvent control group (P < 0.05 or P < 0.01). In the protection group, the NO level were reduced, with the statistically significant differences. (3) In acute irritation test, the levels of NO in 80%TCE group (60.362 +/- 9.817 micromol/mg pro) and 100%TCE group (68.027 +/- 9.354 micromol/mg pro) were significantly different compared with blank control group and solvent control group, (P < 0.05 or P < 0.01); In the protection group, 1% GbE, 10% GbE, 10% VE and 20%VE could reduce the levels of NO, with statistically significant differences.</p><p><b>CONCLUSION</b>TCE can produce the irritation on the dorsal skin of BALB/c hairless mice and induce the significant increase of the NO levels. GbE and VE can protect the skin from TCE irritation damage.</p>

Mechanisms and effects of biosynthesis and apoptosis in repair of full-thickness skin defect with collagen-chitosan dermal stent / 中华整形外科杂志

<p><b>OBJECTIVE</b>To investigate biosynthetic and apoptotic mechanisms in repair of full thickness skin defect with collagen-chitosan porous scaffold transplantation, and to determinate differences between wound repair with the scaffold transplantation and scar healing without the scaffold transplantation.</p><p><b>METHODS</b>The full thickness skin defects were made on 10 Bama miniature pigs and the bilayer dermal equivalent (BDE) composed of collagen-chitosan porous scaffold and silicone membrane was transplanted on wounds. Surfaces of wounds were observed at 1, 2, and 3 weeks after the BDE transplantation, and so were done the wound repairs after epidermis had been grafted for 2 weeks on surface of the scaffold which had been transplanted on skin defect wounds for 2 weeks. At the same time, TGF-beta1 expressions, apoptosis and self collagen replacement of scaffolds in wounds were detected in situ by immunohistochemical staining, terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end labeling (TUNEL) and picrosirius red polarized light. Wounds without scaffold transplantation were studied as control.</p><p><b>RESULTS</b>1) Wounds with the scaffold transplantation were different from granulation tissue. 2) The peak of TGF-beta1 expression in the scaffold wounds was from 1 to 2 weeks after BDE transplantation, and TGF-beta1 expressions decreased continuously from 3 to 4 weeks. TGF-beta1 expressions increased continuously in the control wounds from 1 to 3 weeks and decreased on 4 weeks. TGF-beta1 expressions in the scaffold wounds on 1st and 2nd week were significantly higher than those in the corresponding control wounds, whereas, TGF-beta1 expressions in the scaffold wounds on 3rd and 4th week were significantly lower than those in the corresponding control wounds. 3) Apoptosis increased continuously in the scaffold wounds from 2 to 4 weeks after BDE transplantation, and so did in the control wounds from 3 to 4 weeks. However, apoptosis signals in the scaffold wounds on 2nd, 3rd, and 4th week after BDE transplantation were significantly more than those in the corresponding control wounds, and there was no difference between apoptosis signals in the scaffold wounds on 1st week after BDE transplantation and those in the corresponding control wounds. 4) Observation by picrosirius red polarized light method: self collagen began to synthesize in the scaffold wounds on 1st week after BDE transplantation, and scaffolds had been replaced by self collagen from 2 to 3 weeks after BDE transplantation.</p><p><b>CONCLUSIONS</b>Collagen-chitosan porous scaffold plays a very important role in wound healing of full thickness skin defect. The mechanisms of wound repair by dermal scaffold are different from those by granulation and scar healing. It has a good future in repairing skin defect.</p>

Toxicidad aguda oral y ensayos de irritación de extractos acuoso e hidroalcohólico de Momordica charantia L / Acute oral toxicity and irritation tests in aqueous hydroalcoholic extracts from Momordica charantia L

Fundamentación: los extractos de Momordica charantia L. poseen potencial terapéutico avalado científicamente que posibilita el empleo de esta planta en diversas enfermedades, sobre todo en la diabetes, por lo que caracterizar su potencial tóxico es de gran importancia para avalar el empleo de esta planta como agente terapéutico. Objetivos: realizar los estudios de toxicidad aguda oral e irritación ocular y dérmica a extractos acuoso e hidroalcohólico de M. charantia, con la finalidad de caracterizar su potencial toxicológico agudo. Métodos: el ensayo de toxicidad aguda oral se llevó a cabo en ratas Wistar hembras mediante el método de las clases tóxicas agudas, con la dosis máxima de 2 000 mg/kg. Los ensayos de irritación dérmica y ocular se llevaron a cabo en conejos Nueva Zelanda siguiendo los métodos descritos en las normas OECD 404 y 405. Resultados: la evaluación del extracto hidroalcohólico de M. charantia en el ensayo de toxicidad aguda mostró signos tóxicos por causa de la presencia de etanol en el extracto y una ligera disminución del peso corporal que no fue significativa. La administración del extracto acuoso no provocó signos tóxicos ni mortalidad. Ambos extractos se clasificaron en categoría 5 para ubicarse en el rango de toxicidad de una DL50> 2 000 mg/kg. En el ensayo de irritación dérmica y ocular se clasificaron los extractos como no irritantes. Conclusiones: los extractos evaluados mostraron un bajo potencial tóxico agudo tanto por vía oral como tópica.

Rationale: Momordica charantia L. extracts have scientifically-endorsed therapeutical potentialities that make the use of this plant possible in several diseases, mainly for diabetes, so characterizing its toxic potential is of great significance to support this plant as a therapeutical agent. Objectives: to conduct acute oral toxicity and ocular and dermal irritation studies on aqueous hydroalcoholic extracts from M. charantia, with the aim of characterizing its acute toxicological potential. Methods: Acute oral toxicity test was applied to female Wistar rats through acute toxic class method, with maximum dose of 2000 mg/kg. Ocular/dermal irritation tests were made in New Zealand rabbits, following the described methods in OECD standards 404 and 405. Results: the evaluation of M. charantia hydroalcoholic extract in the acute toxicity test showed toxic signs due to ethanol in the extract and a minimum bodyweight reduction that was not significant. The administration of water extract elicited neither toxic signs nor mortality. Both extracts were classified into category 5 within the range of toxicity of DL50> 2 000 mg/kg. The dermal/ocular irritation test indicated that the studied extracts were not irritating. Conclusions: The evaluated extracts showed low acute toxic potential for both oral and topical administration.

Aeroallergen spectrum of 387 patients with allergic rhinitis in Changsha area / 临床耳鼻咽喉头颈外科杂志

OBJECTIVE@#To investigate aeroallergen spectrum of patients with allergic rhinitis in Changsha area and analyze its related factors.@*METHOD@#Skin prick test was carried out in 463 cases with allergic rhinitis using 13 inhaled allergens, and detailed history was collected in all cases.@*RESULT@#Three hundred and eighty-seven cases (83.6%) showed positive reaction to at least one allergen of 13 allergens. The most common allergens found in patients were Dermatophagoides farinae and Dermatophagoides pteronyssinus, followed by tropical mite, Periplaneta americana, Blattella germanica and dog hair. The rate of positive reaction to only one specie allergen were 51.9%, and most of them were positive reaction to mites (49.6%). The degree of positive reaction was significantly related to family history, asthma, age and housing environment.@*CONCLUSION@#The major allergen of allergic rhinitis is mite, and the degree of positive reaction relates to genetics, asthma, age and housing environment.

Biological evaluation of new percutaneous implanting materials / 生物医学工程学杂志

According to ISO 10993 standard series, the biological safety of surface modified pure titanium was studied as a percutaneous device by the test of cytotoxicity in vitro, as well as by the tests of irritation and sensitization. The result from the examination of cytotoxicity in vitro was negative, the skin irritation response was negligible, and the result of test on skin sensitization in guinea pigs was also negligible. So the surface modified pure titanium in this study can be safely used as percutaneous implanting materials.

The pH of commercially available rinse-off products in Sri Lanka and their effect on skin pH.

INTRODUCTION: Initially linked to antimicrobial function, the acidic skin pH plays a key role in permeability barrier homeostasis and integrity of the stratum corneum. Barrier recovery is delayed when acutely perturbed skin sites are exposed to a neutral pH. OBJECTIVE: To evaluate the pH of commercially available rinse-off products in Sri Lanka, and the effect of detergent rinses on skin pH and its recovery rate. METHODS: The pH of 18 rinse-off products was determined using pH indicator paper and a pH meter. The effect of an alkaline (pH 9) and an acid (pH 5.5) rinse-off product on the hand skin pH was compared in 48 healthy volunteers after single and multiple applications. The skin pH of the dorsum of hands was measured in nurses before (n = 131) and during (n = 40) a duty shift that involved frequent hand washing using alkaline soap. RESULTS: Soaps available in Sri Lanka have a pH of 9.1-10.5. The pH of syndets and cleansers range from 5.5-7.0. Five minutes after hand washing, the mean skin pH increased by 1.7 +/- SD 0.5 pH units with alkaline soap, and by 0.8 +/- SD 0.4 pH units with acidic cleanser (p < 0.0001). Recovery of pH was slower when alkaline soap was used. The increase in skin pH was significantly greater when hands were repetitively washed with alkaline soap (p < 0.0001). The mean skin pH values of nurses before (4.9 +/- SD 0.4) and during (5.7 +/- SD 0.7) the work shift were significantly different (p < 0.0001). CONCLUSIONS: Alkalinisation with rinse-off products increases the skin pH with potential functional and clinical implications.

The study of human skin irritation of a novel herbal skin care product and ingredients by human single closed patch testing.

BACKGROUND: The Government Pharmaceutical Organization of Thailand (GPO) has developed many products using liposome nanotechnology and Thai herbal extracts. OBJECTIVE: Evaluate the irritation potential of GPO products on human skin using the single application closed patch test under occlusion. The authors also studied the moisturizing efficacy of a commercial curmin extract cream (GPO curmin cream). MATERIAL AND METHOD: Thirty-six female volunteers were tested with 12 test materials developed by GPO including liposome, curmin extract: tetrahydrocurcuminoids (THC), and commercial curmin cream. Two and a half percent sodium dodecyl sulfate (SDS) was used as positive control. Standard Finn chambers on Scanpor tape with webril cotton were used as occlusive patch test devices. Cutaneous irritation responses were graded after patch removal and the incidence of irritation compared to the positive control was used for evaluation. Corneometer was used to measure skin hydration before and after application of curmin cream. RESULTS: All volunteers completed the present study. The skin irritation effects from the test materials were significantly lower (p-value < 0.001, McNemar statistic test) than the positive control. Measurement of skin hydration after twice daily application of GPO curmin cream was significantly higher (p-value < 0.001, paired t-test) than the control skin. CONCLUSION: The test materials and finished products developed by the GPO are not likely to induce skin irritation under normal conditions of use. Furthermore, twice-daily application of the commercial GPO curmin cream can significantly increase skin hydration.

Determinação da segurança biológica do xampu de cetoconazol: teste de irritação ocular e avaliação do potencial de citotoxicidade in vitro / Determination of the biological reactivity of ketoconazole in shampoo: draize eye test and cytotoxity test

Cetoconazol é um agente antifúngico, que pode ser incorporado em diferentes formas farmacêuticas, como, por exemplo, xampus e cremes. O objetivo do trabalho foi avaliar a segurança biológica in vivo (teste de irritação ocular) e in vitro (teste de citotoxicidade) do xampu de cetoconazol degradado sob ação da luz. Para tanto, a formulação foi exposta à radiação UV-C (254 nm) e foram empregados dois métodos para a determinação quantitativa do cetoconazol: CLAE e ensaio microbiológico. Os resultados demonstraram alteração do cetoconazol em presença da luz - presença de picos secundários no cromatograma e diminuição da atividade antifúngica - entretanto, não demonstraram alteração na segurança biológica entre xampu de cetoconazol e xampu de cetoconazol contendo produtos de degradação.

Ketoconazole is an antifungal agent and can be incorporated into several dosage forms, as an example it could be mentioned shampoos and creams. The aim of this work was to assess the biological reactivity in vivo (Draize eye test) and in vitro (cytotoxity test) of ketoconazole in shampoo degradeted under action of light. The formulation was exposed to UV-C (254 nm) radiation and two methods were used for the quantitative determination of ketoconazole: HPLC and microbiological assay. The results showed alteration in ketoconazole in presence of light - secondary peaks in chromatogram and decrease in antifungal activity - however, no alteration on the biological reactivity between ketoconazole shampoo and ketoconazole shampoo containing degradation products was observed.

Toxicity evaluation of chicken calamus keratin conduit as a tissue-engineering scaffold biomaterial / 南方医科大学学报

<p><b>OBJECTIVE</b>To evaluate the toxicity of chicken calamus keratin (CCK) conduit as a tissue-engineered scaffold material.</p><p><b>METHODS</b>The chemical composition of the leaching solution of CCK was determined by means of ultraviolet spectrometry, and the toxic effects of the solution was evaluated by skin sensitization test in rats, intracutaneous stimulation test in rabbits, acute systemic toxicity test in mice, and cytotoxicity test in L929 cells.</p><p><b>RESULTS</b>The leaching solution of CCK consisted mainly of middle-molecular-weight peptides with a small quantity of macromolecular proteins. Skin sensitization test in rats showed that application of the CCK leaching solution caused no obvious skin reddening, regional edema, or skin necrosis. Intracutaneous injection of the leaching solution in rabbits did not induce obvious skin stimulation manifested by intradermal erythema or edema. In acute systemic toxic test, administration of the leaching solution in mice caused no death, organ dysfunction, cyanosis, tremor, severe peritoneal irritation, ptosis, or dyspnoea. In vitro cytotoxicity test indicated that the cell toxicity of the CCK leaching solution was approximately at 0 level.</p><p><b>CONCLUSION</b>CCK contained in the treated chicken calamus easily undergoes hydrolysis to release mainly some peptides which do not induce obvious toxic effects, suggesting the safe potential applications of CCK conduit as a tissue-engineering biomaterial.</p>