Occupational Risk Factors for Prostate Cancer: A Meta-analysis

Prostate cancer is the second most common cancer in men worldwide. There are many occupational factors that have been suggested to cause prostate cancer. Our aim was to evaluate the evidence for causality by a literature review of occupational factors. We searched literature in Medline and SCOPUS from 1966 to June 30, 2015 to identify occupational risk factors for prostate cancer. The following risk factors were selected: farmers/agricultural workers, pesticides – whole group, and separately organophosphate and organochlorine pesticides, carbamates and triazines, cadmium, chromium, cutting fluids, acrylonitrile, rubber manufacturing, whole body vibration, shift work, flight personnel, ionizing radiation, and occupational physical activity. For each factor a literature search was performed and presented as meta-analysis of relative risk and heterogeneity (Q and I² index). A total of 168 original studies met the inclusion criteria with 90,688 prostate cancer cases. Significantly increased risks were observed for the following occupational exposures: pesticides (metaRR = 1.15, 95% confidence interval [CI] = 1.01–1.32; I² = 84%), and specifically group of organochlorine pesticides (meta relative risk [metaRR] = 1.08, 95% CI = 1.03–1.14; I² = 0%), chromium (metaRR = 1.19, 95% CI = 1.07–1.34; I² = 31%), shift work (metaRR = 1.25, 95% CI = 1.05–1.49; I² = 78%) and pilots (metaRR = 1.41, 95% CI = 1.02–1.94; I² = 63%) and occupational physical activity in cohort studies (metaRR = 0.87, 95% CI = 0.81–0.94; I² = 0%). The literature review supports a causal association for a few of the previously suggested factors.

Experimental acrylonitrile butadiene styrene and polyamide evisceration implant: a rabbit clinical and histopathology study / Estudo clínico e histopatológico em coelhos eviscerados com utilização de implantes de poliamida e acrilonitrila butadieno estireno

The purpose of this study was to evaluate acrylonitrile butadiene styrene (ABS) and polyamide implants in rabbits submitted to evisceration at the macroscopic and microstructure level and to assess clinical response and histopathological changes as well. For the experimental study implants of 12mm diameter were prepared by rapid prototyping, weighed and the outer and inner surfaces evaluated macroscopically and by electron microscopy. In addition, a compression test was performed and ultrastructural damage was then determined. After evisceration of the left eyeball, nine New Zealand rabbits received ABS implants and nine others received polyamide implants. The animals were assessed daily for 15 days after surgery and every seven days until the end of the study (90 days). Histopathological evaluation was performed at 15, 45 and 90 days after surgery. The ABS implants weighed approximately 0.44g, while the polyamide ones weighed 0.61g. Scanning electron microscopy demonstrated that the ABS implants had regular-sized, equidistant micropores, while the polyamide ones showed micropores of various sizes. The force required to fracture the ABS implant was 14.39 ±0.60 Mpa, while for the polyamide one, it was 16.80 ±1.05 Mpa. Fifteen days after surgery, we observed centripetal tissue infiltration and scarce inflammatory infiltrate. Implants may be used in the filling of anophthalmic cavities, because they are inert, biocompatible and allow tissue integration.(AU)

Avaliou-se a macroscopia, a microestrutura, a resposta clínica e histopatológica de implantes de acrilonitrila butadieno estireno (ABS) e poliamida em coelhos submetidos à evisceração. Para o estudo experimental, os implantes foram elaborados por meio de prototipagem rápida, com 12mm de diâmetro, pesados e tiveram suas superfícies avaliadas macroscopicamente e por microscopia eletrônica de varredura. Adicionalmente, foi realizado ensaio de compressão para determinar a força necessária para fraturar os implantes. Após a evisceração do olho esquerdo, nove coelhos da raça Nova Zelândia receberam implantes de poliamida e nove outros receberam implantes de ABS. Os animais foram avaliados diariamente nos primeiros 15 dias após a cirurgia e a cada sete dias até o fim do período experimental (90 dias). Avaliação histopatológica foi realizada aos 15, 45 e 90 dias após a cirurgia. Os implantes de ABS pesaram 0,44g, e os de poliamida 0,61g. A microscopia eletrônica de varredura demonstrou que os implantes de ABS eram formados por microporos equidistantes, enquanto os de poliamida apresentavam microporos de vários tamanhos. A força necessária para fraturar os implantes de ABS foi de 14.39±0.60 Mpa, enquanto para os de poliamida foi de 16.80±1.05Mpa. Quinze dias após a cirurgia, foi observada infiltração fibrovascular centrípeta. Os implantes podem ser utilizados para correção de cavidades anoftálmicas por se mostrarem inertes, biocompatíveis e permitirem a infiltração tecidual.(AU)

O papel da concentração de nanofibras e da composição da matriz resinosa nas propriedades flexurais de compósitos experimentais baseados em nanofibras / Flexural properties of experimental nanofiber reinforced composite are affected by resin composition and nanofiber/resin ratio

O objetivo do presente estudo foi de avaliar a influência de soluções de resina com diferentes proporções de monômeros e diferentes concentrações em massa de nanofibras nas propriedades flexurais de compósitos resinosos experimentais reforçados com nanofibras de poliacrilonitrila (PAN). Materiais e métodos: Nanofibras de PAN foram produzidas pelo processo de eletrofiação e caraterizadas por teste de tração e microscopia eletrônica de varredura (MEV). Os compósitos experimentais foram produzidos pela infiltração das mantas de nanofibras com diferentes misturas de BisGMA-TEGDMA (BisGMA/TEGDMA: proporções em % massa de 30/70, 50/50, e 70/30). Foram incorporadas diferentes concentrações em massa de nanofibras (de 0% a 8%). Espécimes em forma de barra foram seccionados a partir de blocos do compósito experimental e armazenados em água na temperatura de 37oC por 24h anteriormente à realização dos testes de flexão de três pontos. Foram avaliados a resistência flexural (RF), o módulo flexural (MF) e o trabalho de fratura (TF). Resultados: Os testes de tração das nanofibras de PAN demonstraram um comportamento anisotrópico das mantas de nanofibras. As propriedades mecânicas exibiram maiores valores na direção perpendicular ao eixo de rotação do coletor metálico utilizado na produção das fibras por eletrofiação. Maiores proporções de BisGMA nas misturas de resina resultaram em maiores valores de RF e MF, o que não ocorreu para os valores de TF. A adição de diferentes concentrações de nanofibras não afetou as propriedades de RF e MF em comparação com o grupo controle (resina pura) (p>0.05). No entanto, a adição das nanofibras promoveu um aumento significante do TF, principalmente para as misturas de resina com maior proporção de TEGDMA (p<0,05). Significância: A inclusão de nanofibras de PAN em resinas de modo a formar compósitos resinosos reforçados por nanofibras não afetou negativamente as propriedades flexurais do material e resultou em um aumento significativo da...

The present study had the objectives to evaluate the influence of different resin blends concentrations and nanofibers mass ratio on flexural properties of experimental Poliacrylonitrile (PAN) nanofibers reinforced composite. Materials and Methods: Poliacrylonitrile (PAN) nanofibers mats were produced by electrospinning and characterized by tensile testing and scanning electron microscopy (SEM). Experimental resin-fiber composite beams were manufactured by infiltrating PAN nanofiber meshs with varied concentrations of BisGMA-TEGDMA resin blends (BisGMA/TEGDMA: 30/70, 50/50 and 70/30 weight %). The mass ratio of fiber to resin varied from 0% to 8%. Beams were cured and stored in water at 37oC. Flexural strength (FS), flexural modulus (FM) and work of fracture (WF) were evaluated by three-point bending test after 24 hs storage. Results: The tensile properties of the PAN nanofibers indicated an anisotropic behavior being always higher when tested in a direction perpendicular to the rotation of the collector drum. Except for WF, the other flexural properties (FS and FM) were always higher as the ratio of BisGMA to TEGDMA increased in the neat resin beams. The addition of different ratios of PAN fibers did not affect FS and FM of the composite beams as compared to neat resin beams (p>0.05). However, the addition of fibers significantly increased the WF of the composite beams, and this was more evident for the blends with higher TEGDMA ratios (p<0.05). Significance: The inclusion of PAN nanofibers into resin blends did not negatively affect the properties of the composite and resulted in an increase in toughness that is a desirable property for a candidate material for restorative application.

O papel da concentração de nanofibras e da composição da matriz resinosa nas propriedades flexurais de compósitos experimentais baseados em nanofibras / Flexural properties of experimental nanofiber reinforced composite are affected by resin composition and nanofiber/resin ratio

O objetivo do presente estudo foi de avaliar a influência de soluções de resina com diferentes proporções de monômeros e diferentes concentrações em massa de nanofibras nas propriedades flexurais de compósitos resinosos experimentais reforçados com nanofibras de poliacrilonitrila (PAN). Materiais e métodos: Nanofibras de PAN foram produzidas pelo processo de eletrofiação e caraterizadas por teste de tração e microscopia eletrônica de varredura (MEV). Os compósitos experimentais foram produzidos pela infiltração das mantas de nanofibras com diferentes misturas de BisGMA-TEGDMA (BisGMA/TEGDMA: proporções em % massa de 30/70, 50/50, e 70/30). Foram incorporadas diferentes concentrações em massa de nanofibras (de 0% a 8%). Espécimes em forma de barra foram seccionados a partir de blocos do compósito experimental e armazenados em água na temperatura de 37oC por 24h anteriormente à realização dos testes de flexão de três pontos. Foram avaliados a resistência flexural (RF), o módulo flexural (MF) e o trabalho de fratura (TF). Resultados: Os testes de tração das nanofibras de PAN demonstraram um comportamento anisotrópico das mantas de nanofibras. As propriedades mecânicas exibiram maiores valores na direção perpendicular ao eixo de rotação do coletor metálico utilizado na produção das fibras por eletrofiação. Maiores proporções de BisGMA nas misturas de resina resultaram em maiores valores de RF e MF, o que não ocorreu para os valores de TF. A adição de diferentes concentrações de nanofibras não afetou as propriedades de RF e MF em comparação com o grupo controle (resina pura) (p>0.05). No entanto, a adição das nanofibras promoveu um aumento significante do TF, principalmente para as misturas de resina com maior proporção de TEGDMA (p<0,05). Significância: A inclusão de nanofibras de PAN em resinas de modo a formar compósitos resinosos reforçados por nanofibras não afetou negativamente as propriedades flexurais do material e resultou em um aumento significativo da...

The present study had the objectives to evaluate the influence of different resin blends concentrations and nanofibers mass ratio on flexural properties of experimental Poliacrylonitrile (PAN) nanofibers reinforced composite. Materials and Methods: Poliacrylonitrile (PAN) nanofibers mats were produced by electrospinning and characterized by tensile testing and scanning electron microscopy (SEM). Experimental resin-fiber composite beams were manufactured by infiltrating PAN nanofiber meshs with varied concentrations of BisGMA-TEGDMA resin blends (BisGMA/TEGDMA: 30/70, 50/50 and 70/30 weight %). The mass ratio of fiber to resin varied from 0% to 8%. Beams were cured and stored in water at 37oC. Flexural strength (FS), flexural modulus (FM) and work of fracture (WF) were evaluated by three-point bending test after 24 hs storage. Results: The tensile properties of the PAN nanofibers indicated an anisotropic behavior being always higher when tested in a direction perpendicular to the rotation of the collector drum. Except for WF, the other flexural properties (FS and FM) were always higher as the ratio of BisGMA to TEGDMA increased in the neat resin beams. The addition of different ratios of PAN fibers did not affect FS and FM of the composite beams as compared to neat resin beams (p>0.05). However, the addition of fibers significantly increased the WF of the composite beams, and this was more evident for the blends with higher TEGDMA ratios (p<0.05). Significance: The inclusion of PAN nanofibers into resin blends did not negatively affect the properties of the composite and resulted in an increase in toughness that is a desirable property for a candidate material for restorative application.

The effects of acrylonitrile on T lymphocyte subsets and expression of toll-like receptor 4 in rats / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To explore the effects of acrylonitrile on T lymphocyte subsets, expression of toll-like receptor 4 and related cytokines in rats.</p><p><b>METHODS</b>Sixty-four Sprague-Dawley rats were randomly divided into 4 female groups and 4 male groups, and there were 8 rats in each group. Rats in each group were respectively given a single dose of 0, 5, 10 and 20 mg/kg acrylonitrile by gavage, once a day, 5 days a week, for 13 weeks. Blood and spleen T lymphocyte subsets was detected by flow cytometry, the mRNA expression of TLR4, IL-1β and TNF-α was analyzed by real-time quantitative PCR, the protein expression of TLR4 was evaluated by Western blot.</p><p><b>RESULTS</b>Compared with control group, the percentages of blood CD3, CD4 T cells in 20 mg/kg female group and CD4/CD8 ratio in 5, 10 and 20 mg/kg female groups was significantly decreased, CD8 T cells in 20 mg/kg group was significantly increased (P < 0.05 or P < 0.01), blood CD3 T cells in 5 mg/kg male group, CD4 T cells and CD4/CD8 ratio in 20 mg/kg male groups were lower than that of control group, CD8 T cells in 20 mg/kg make group was significantly in oreased (P < 0.05 or P < 0.01). Spleen CD4, CD8 T lymphocyte percentages and CD4/CD8 ratio in 20 mg/kg female group decreased significantly, CD8 T cells in 20 mg/kg male group was significantly increased (P < 0.05 or P < 0.01), spleen CD3, CD4, CD8 T cells in 20 mg/kg male group and CD4/CD8 ratio in 10, 20 mg/kg male groups was also significantly decreased, CD3 T cells in 20 mg/kg and CD8 T cells in 10, 20 mg/kg male groups were significantly increased (P < 0.05 or P < 0.01) (TLR4 mRNA was lower expressed in 5, 10 and 20 mg/kg male groups and 10 mg/kg female group (P < 0.05 or P < 0.01), and TLR4 protein in 5 mg/kg female group and 20 mg/kg male group was significantly lower than control group (P < 0.05). The expression level of IL-1β mRNA was significantly decreased in 5, 10 and 20 mg/kg female group and 5, 10 mg/kg male group (P < 0.05 or P < 0.01), TNF-α mRNA was lower expressed in 10, 20 mg/kg female groups and 5, 10 mg/kg male groups (P < 0.01).</p><p><b>CONCLUSION</b>Acrylonitrile may lead to the changes of CD3, CD4, CD8 T lymphocyte percentages and CD4/CD8 ratio in rat blood and spleen, and also significantly effected the expression level of TLR4 mRNA and protein together with the secretion of IL-1β, TNF-α. This may cause effects on the cellular immune function.</p>

Estudo da atividade biológica de adutos Morita-Baylis-Hillman sobre Trypanosoma cruzi / Study of the biological activity of Morita-Baylis-Hillman adducts against Trypanosoma cruzi

A doença de Chagas, causada pelo protozoário hemoflagelado Trypanosoma cruzi, consiste em um grave problema de saúde pública na América Latina, com cerca de 7 a 8 milhões de pessoas infectadas. O benznidazol é atualmente o único fármaco disponível para o tratamento, apresentando boa atividade na fase aguda, mas com eficácia questionada na fase crônica, além de apresentar severos efeitos colaterais e longo período de tratamento. Tendo em vista a sua fácil síntese e baixo custo, adutos aromáticos oriundos da reação Morita-Baylis-Hillman têm sido considerados promissores como quimioterápicos. Neste sentido, foi avaliada a atividade tripanocida e citotóxica de seis adutos Morita-Baylis-Hillman. Para analisar possíveis efeitos dos adutos sobre estruturas específicas do protozoário foi utilizado a microscopia confocal a laser, através da marcação com Rodamina 123, MitoSOXT, Laranja de Acridina e Kit Live/Dead(R). As alterações morfológicas em parasitas submetidos ao tratamento foram acompanhadas por microscopia eletrônica de transmissão. Nossos resultados mostraram que todos os compostos foram capazes de inibir o crescimento de formas epimastigotas e causaram uma diminuição da viabilidade em formas tripomastigotas, apresentando uma moderada citotoxicidade para células de mamíferos. Os adutos MBH1, MBH2, MBH5 e MBH7 também foram efetivos em inibir a infecção de macrófagos e diminuir a viabilidade das formas amastigotas. Os compostos não foram capazes de alterar os níveis de produção do óxido nítrico em macrófagos. Análises pela microscopia confocal e microscopia eletrônica de transmissão (MET) apontam a mitocôndria como principal alvo intracelular destes compostos. Alterações compatíveis com a perda da viabilidade e morte celular por necrose e autofagia foram observadas por MET. Os resultados obtidos neste trabalho colocam os adutos Morita -Baylis-Hillman em evidência como agentes promissores para o tratamento da tripanossomíase americana.

Portable gas chromatography for determining airborne acrylonitrile in workplaces / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To establish a method for rapid determination of airborne acrylonitrile using a portable gas chromatograph.</p><p><b>METHODS</b>A single standard sample of acrylonitrile was prepared in a laboratory and sampled by the built-in constant flow pump of the portable gas chromatograph. The sample was then preconcentrated by the preconcentrator, thermally desorbed, separated by capillary columns, and detected by a micro argon ionization detector to determine the retention time. Retention time was then used to perform qualitative analysis. Under the set condition of gas chromatography, the external standard method was used to create a standard curve for quantitative analysis of acrylonitrile.</p><p><b>RESULTS</b>The linear range of acrylonitrile on the portable gas chromatograph was 0.25 to 3.00 mg/m(3). The regression equation was y = 10(-5) x-0.0275, r = 0.9977. The limit of detection was 0.005 mg/m(3), and the lower limit of quantification was 0.25 mg/m(3). The relative standard deviation was lower than 7.09%, and the degree of accuracy was 91.09-105.54%.</p><p><b>CONCLUSION</b>Portable gas chromatography is a simple, repeatable, and accurate method for rapid determination of airborne acrylonitrile.</p>

Avaliação da atividade biológica de adutos derivados da reação morita-baylis-hillman sobre Trypanosoma cruzi: uma abordagem molecular, citoquímica e ultraestrutural / Biological activity evaluation of morita-baylis-hillman adducts against Trypanosoma cruzi: a molecular, cytochemical and ultrastructural approach

A doença de Chagas, causada pelo protozoário Trypanosoma cruzi, é um importante problema de saúde pública na América Latina, com cerca de 7,6 milhões de pessoas infectadas. O benznidazol e o nifurtimox são os únicos fármacos disponíveis para o tratamento, e além de apresentarem sérios efeitos colaterais, a sua eficácia na fase crônica da doença ainda é controversa. Neste sentido, nós sintetizamos o aduto Morita-Baylis-Hillman 3-hidroxi-2-metileno-3-(4-nitrofenilpropanonitrilo) (MBHA 3) e avaliamos sua atividade biológica sobre o T. cruzi. O MBHA 3 inibiu fortemente o crescimento das formas epimastigotas, com IC(50) / 72h de 28,5 µM e causou intensa lise de tripomastigotas, com IC(50)/ 24h de 25,5 µM. A análise ultraestrutural mostrou alterações morfológicas significantes, como arredondamento do corpo celular e desorganização intracelular. Alterações indicativas de apoptose, autofagia ou necrose também foram observadas nas células mais afetadas. A fim de melhor compreender o mecanismo envolvido na morte celular induzida pelo composto, nós utilizamos a microscopia confocal e a citometria de fluxo aliadas a sondas fluorescentes, como anexina-V (AV)/ iodeto de propídio (IP); Calceína-AM (CA)/ homodímero de etídio (HE); laranja de acridina (LA) e rodamina 123. O tratamento com 6 e 12 µg/ mL revelou uma alta porcentagem de células viáveis pela CA/ HE, mas também induziu alterações mitocondriais e aumento da marcação com a LA, sugerindo que um processo de morte celular programada (MCP) por autofagia poderia estar ocorrendo. Por outro lado, o tratamento com 24 µg/ mL levou à perda de viabilidade celular com danos excessivos sobre a membrana plasmática e mitocondrial e fragmentação inespecífica do DNA. Em conclusão, nossos achados sugerem que o MBHA 3, em alta concentração, induz MCP por necrose em T. cruzi.

The effects of acrylonitrile on cell apoptosis, proliferation and related genes expression of rat normal and tumor glial cells / 中华预防医学杂志

<p><b>OBJECTIVE</b>To study the effect of acrylonitrile (ACN) to cell growth, apoptosis, proliferation and related gene expression of rat normal glial cells (DI TNC1) and tumor glial cells (C6).</p><p><b>METHODS</b>The concentration of ACN on DI TNC1 and C6 were 25, 50 and 75 microg/ml. For cell growth, proliferation and apoptosis assay, the treated time was 24 hours, for microarray assay, the treated time was 4 and 24 hours.</p><p><b>RESULTS</b>After treatment of DI TNC1 cell with 25,50 and 75 microg/ml ACN, the DNA synthesis index were decreased 93.1%, 81.3% and 74.9% as compared to control respectively, the apoptosis index was increased 118%, 122% and 143% as compared to controls respectively. The DNA synthesis and apoptosis indexes of C6 cell showed no change after treatment with ACN. The cell cycle and apoptosis pathway related genes, such as cyclin and p53, also showed changes after treatment with ACN.</p><p><b>CONCLUSION</b>ACN inhibited the cell proliferation of DI TNC1, induced the apoptosis of DI TNC1 and had no effect on cell proliferation and apoptosis of C6 cells, and the related regulation gene expression changes further confirmed the results.</p>

Hesperidin, an antioxidant flavonoid, prevents acrylonitrile-induced oxidative stress in rat brain

Acrylonitrile [ACN] is a volatile, toxic liquid used as a monomer in the manufacture of synthetic rubber, styrene plastics, acrylic fiber and adhesives. ACN is a potent neurotoxin. A role for free radical-mediated lipid peroxidation in the toxicity of ACN has been suggested. We examined the ability of hesperidin, an antioxidant flavonoid, to attenuate ACN-induced alterations in lipid peroxidation in rat brains. The daily oral administration of ACN to male albino rats in a dose of 50 mg/kg bwt for a period of 28 days produced a significant elevation in brain lipid peroxides measured as malondialdehyde [MDA] amounting to 107%, accompanied by a marked decrease in brain reduced glutathione [GSH] content reaching 63%. In addition, ACN administration resulted in significant reductions in the enzymatic antioxidant parameters of brain; superoxide dismutase [SOD], catalase [CAT], glutathione peroxidase [GSH-Px] and glutathione-S-transferase [GST] recording 43%, 64%, 52% and 43%, respectively. On the other hand, pretreatment with hesperidin and its co-administration with ACN once daily in a dose of 200 mg/kg bwt, i.p. for 28 days ameliorated ACN-induced alterations in brain lipid peroxidation. These results suggest that hesperidin may have a beneficial role against ACN-induced oxidative stress in brain; an effect that is mainly attributed to the antioxidant property of hesperidin

Potential protective effect of grape seed extract against acrylonitrile-induced mutagenicity in rats

Acrylonitrile [ACN], an environmental toxic pollutant, has been detected in drinking water, food products and occupational environment. ACN is reported as a potent in vivo and in vitro mutagen and carcinogen in human and experimental animals. Grape seed proanthocyanidine extract [GSE] is a highly bioavailable biologically active polyphenolic bioflavonoid. It is a potent antioxidant posses a broad spectrum of pharmacological and therapeutic activities against free radicals, DNA damage and oxidative stress. The objective of the present study was to investigate the possible in vivo protective effects of GSE against ACN-induced micronucleus and chromosomal aberrations in male rats. Animals were exposed to a single s/c dose of ACN [115 mg/kg body weight]. Another two groups of animals were pretreated with GSE in a dose of 100 and 200 mg/kg body weight orally for seven consecutive days prior to ACN administration [single s/c dose of 115 mg/kg body weight]. The animals were subjected to cytogenetic analysis in bone marrow by micronucleus induction and chromosomal aberrations assays. The present results indicate that ACN significantly induced micronuclei and chromosomal aberrations. Pretreatment with GSE significantly improved these mutagenic effects in a dose related manner

Application of micronucleus test of buccal mucosal cells in assessing the genetic damage of workers exposed to acrylonitrile / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To investigate the application of micronucleus test of buccal mucosal cells in monitoring the genetic effect of acrylonitrile in the population exposed to the acrylonitrile.</p><p><b>METHODS</b>Forty-one healthy male workers in a chemical factory in Shanghai were selected as the low concentration acrylonitrile exposed group while forty-seven healthy male workers in an acrylonitrile factory in Shanghai were selected as the intermediate concentration acrylonitrile exposed group. At the same time, thirty-one male workers who had no toxicant exposure and lived in the same community were selected as the control group. The micronucleus test in buccal mucosal cells and lymphocytes were used respectively for assessing the genetic damage status of these men.</p><p><b>RESULTS</b>The rate of micronucleus in buccal mucosal cells in both acrylonitrile groups (the low concentration group: 3.68% +/- 2.72%; the intermediate concentration group: 4.00% +/- 2.38%) was significantly higher than that in the control group (2.03% +/- 2.20%) (P < 0.05). The rate of micronucleus in the intermediate concentration group (4.23% +/- 3.34%) was significantly higher than that in the control group (2.48% +/- 1.46%) (P < 0.05). There was the correlation between the micronucleus test of buccal mucosal cells and the micronucleus test of the lymphocytes in the peripheral blood in the acrylonitrile exposed population (r = 0.299-0.359, P < 0.05).</p><p><b>CONCLUSION</b>The micronucleus test of buccal mucosal cells replacing the micronucleus test of the lymphocytes in the peripheral blood can be used as one of the screening indexes in the surveillance of the genetic damage in the acrylonitrile exposed population.</p>

Effects of acrylonitrile on the activities of antioxidant enzymes and levels of lipid peroxidation in rat testes / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To explore the mechanism of male reproductive toxicity induced by acrylonitrile (ACN).</p><p><b>METHODS</b>Male Sprague-Dawley rats were daily administrated ACN by intraperitoneal injection 5 times a week for 13 weeks at the dose of 0, 7.5, 15.0 and 30.0 mg/kg body weight, respectively. The rats were sacrificed and testes were removed at the end of 4, 8, 13 or 15 weeks, respectively. The activities of glutathione peroxidase (GSH-Px), superoxide dismutase (SOD) and glutathione S-transferase (GST) and the levels of glutathione (GSH) and malonaldehyde (MDA) were detected in testes.</p><p><b>RESULTS</b>Following ACN treatment of 4 weeks, the levels of GSH in ACN 15.0 mg/kg and 30.0 mg/kg group were (7.44 +/- 0.77) mg/g pro and (6.95 +/- 0.77) mg/g pro respectively, and the activity of GSH-Px was (70.89 +/- 4.01) U/mg pro in 30.0 mg/kg group, all of which were significantly higher than the control group (P < 0.05, P < 0.01). After 8 weeks, the levels of GSH decreased to (2.50 +/- 0.94) mg/g pro in ACN 30.0 mg/kg group (P < 0.01); the activities of SOD increased to (102.08 +/- 16.08) NU/mg pro and (113.30 +/- 17.20) NU/mg pro in ACN 15.0 mg/kg and 30.0 mg/kg group (P < 0.01). After 13 weeks, the levels of GSH declined in ACN 15.0 mg/kg and 30.0 mg/kg group, and the activities of GST decreased in ACN 30.0 mg/kg group, and of GSH-Px decreased in both doses group. However, the level of MDA [(0.68 +/- 0.16) nmol/mg pro] were significantly higher in 30.0 mg/kg group than that in control group [(0.38 +/- 0.12) nmol/mg pro] (P < 0.01). 2 weeks after stopping ACN treatment, the level of GSH restored to normal but the levels of MDA or the activity of GSH-Px in 30.0 mg/kg group were still higher or lower respectively than those of control (P < 0.05).</p><p><b>CONCLUSION</b>ACN may impair the balance of antioxidant system, thus induce lipid peroxidation damage to rat testes.</p>

Effects of acrylonitrile in drinking water on monoamine neurotransmitters and its metabolites in male rat brains / 中华预防医学杂志

<p><b>OBJECTIVES</b>To elucidate the possible involvement of monoamine neurotransmitters in the development of neurobehavioral damage produced by acrylonitrile in drinking water in male rat brains.</p><p><b>METHODS</b>Totally 30 male SD rats were randomly divided into three groups, the control group (n = 10), low dosage group (n = 10), and high dosage group (n = 10), which were respectively administered 0 mg/L, 50 mg/L, 200 mg/L acrylonitrile (AN) in drinking water. The treatment was lasted for 12 weeks. Seven animals were randomly selected from each group for determination of monoamine neurotransmitters in striatum and cerebellum by high performance liquid chromatography with electrochemical detector and activities of monoamine oxidase in cortex.</p><p><b>RESULTS</b>The contents of dopamine in the striatum of low and high dosage groups were decreased to (2.2 +/- 0.7) and (3.2 +/- 2.0) microg/g wet tissue, respectively, and compared with that of control group (9.0 +/- 4.2) microg/g wet tissue, the differences were statistically significant. There were no statistical differences among the contents of dopamine in the cerebellum of all rats, and the levels of 3,4-dihydroxyphenylacetic acid (DOPAC), the major metabolite of dopamine in the cerebellum were (186 +/- 41), (245 +/- 90) and (115 +/- 65) ng/g wet tissue in the control, low and high dosage groups, respectively and in low-dosage group they were significantly higher than those in other groups. There was dosage-dependently decreasing of the contents of serotonin of striatum in the control (249 +/- 34) ng/g wet tissue, low dosage (155 +/- 95) ng/g wet tissue and high dosage groups (128 +/- 101) ng/g wet tissue.</p><p><b>CONCLUSION</b>This study underlines the importance of alterations in the monoamine neurotransmitters system as a possible causative mechanism behind the behavioural and functional changes produced by acrylonitrile.</p>

A Stereotactic Device for Gamma Knife Irradiation to Cell Lines

OBJECTIVE: The purpose of this work is to build a well-plate holder for in vitro gamma knife irradiation to cell lines and to verify its validity. METHODS: A well-plate holder for gamma ray irradiation to cell lines using gamma knife was made of acrylonitrile. Inside the holder, a hexahedral space was excavated to hold well plates. The actual radiation dose to cell lines was obtained by comparing the relative dose of the holder with the gamma knife quality assurance standard phantom. All parameters necessary for cell line irradiation were calculated using the commercial software, Leksell Gamma Plan(R) v5.32. Dose distribution was drawn to six and ninety-six wells to search for optimal parameters for cell line irradiation. RESULTS: The dose rate at the center of the well-plate holder was 94+/-4% of the standard phantom and resulting absolute dose at the central area was 2.1+/-0.1Gy/min. The dose distributions of our phantom was the same as that of the standard phantom in qualitative comparison using an image analyzing software. Appropriate isodose lines which fit with the practical situation were obtained with the 18mm collimator of the Gamma knife. CONCLUSION: Our results show that a well-plate holder for gamma knife irradiation is confident and accurate. It can be used for the study of in vitro cellular effects by gamma knife irradiation in the future.

Study on mitochondrial DNA damage in peripheral blood nucleate cells of the workers exposed to acrylonitrile / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To study the potential aging effect on workers exposed to acrylonitrile (ACN).</p><p><b>METHODS</b>The deletion rates of mitochondrial DNA (mtDNA) in peripheral blood nucleate cells of 47 exposed workers and 47 non-exposed workers (as control), as well as 12 old people and 12 young people were measured with polymerase chain reaction (PCR).</p><p><b>RESULTS</b>The positive rates of mtDNA deletion in peripheral blood nucleate cells were 17.02% in the workers exposed to ACN and 25.00% in group of old people. However, the mtDNA deletion was not detected in the control group and young people.</p><p><b>CONCLUSIONS</b>ACN could induce mtDNA deletion in peripheral blood nucleate cells of the exposed workers. There may be a potential molecular effect of occupational ACN exposure on workers' aging.</p>

Study on production of acrylamide by microbial method (II)--enzyme catalytic kinetics and de-active dynamics of nitrile hydratase / 生物工程学报

The hydration reaction by microbial method is the crisis of the procedure of acrylamide production from acrylonitrile. This research studied the enzyme catalytic kinetics and de-active kinetics of nitrile hydratase in the type of free cell. Firstly, the effects of the concentration of cells, the temperature, pH value, the concentration of acrylonitrile and the concentration of acrylamide on the activity of nitrile hydratase was investigated. The result is that the temperature and the concentration of acrylamide are the most important among these factors. The activity of the nitrile hydratase was 5659 u/mL (broth) at 28 degrees C; the counterpart was only 663 u/mL (broth) at 5 degrees C. And the activity of NHase in solution of 45% acrylamide was just about half of that in solution of 5% acrylamide. After study on the relation of temperature and the reaction speed, It was found that the activation energy of the hydration of NHase was 65.57 kJ.mol-1. This paper studied the effects of concentration of cells, temperature, pH value, concentrations of acrylonitrile and acrylamide on the deactivation of Nhase, as well as the related enzyme de-active kinetics. The result also showed that the temperature and the concentration of acrylamide are the most important among these factors. In solution of 35% acrylamide, the residual activity was about 0% of the original value after 55 h; but in solution of 10% acrylamide, after the same period of time, the residual activity was 50% of the original one. It was also found that the concentration of acrylonitrile had little effect on the stability of NHase. The coefficient of deactivation at 28 degrees C was 21.77 times of the one at 5 degrees C. Correlating the temperature and the coefficient of deactivation, the activation energy of the de-active reaction was found to be 92.28 kJ.mol-1.

A Case of Cyanide Poisoning Caused by Acrylonitrile Inhalation

Acrylonitrile is most commonly used aliphatic nitrile compounds characterized by the structural formula R-C=N and used mossy to make acrylic fibers, plastics, synthetic rubber, and wall coverings. In recent, because of its extensive usage and the rapid expansion of the chemical industry, many poisonings have been reported and many studies on its health effects have been performed. Acute toxicity resembles cyanide poisoning and results mainly in effects on the nervous system. High exposure also can cause temporary damage to red blood cells and the liver and can cause lead to death. Because long-term occupational exposure to the acrylonitrile has been with cancer in humans, the U.S EPA classifies acrylonitrile as probable carcinogen. For this reason, The federal government has developed regulations and advisories to protect individuals firm the potential health effects of acylonitrile in the environment, but there are few studies, case reports and regulations of the government in our country. We experienced acute poisoning caused by acrylonitrile inhalation that occurred in an industrial accident. So, we report this case with literature reveiw.

Estudo antômico do retalho lateral do braço / Anatomical study of the lateral arm flap

Com o objetivo de estudar a anatomia do retalho lateral do braço, foram realizadas dissecçoes de 45 membros superiores direitos de 45 cadáveres. A idade variou de 25 a 81 anos. Todos eram do sexo masculino. Eles foram divididos em três grupos de estudo, de acordo com a metodologia empregada, que variou conforme a soluçao contrastante: azul de metileno, vinil/tinta e óxido de chumbo. Os dados obtidos foram relacionados com valores antropométricos individuais. As dimensoes do retalho, emergência do primeiro vaso septal, perfuraçao do septo intermuscular lateral pelo feixe vasculonervoso puderam ser estimuladas por meio de adequaçoes cujas variáveis eram o comprimento e perímetro do braço. Presença de anastomose vascular distal do retalho, da artéria colateral radial posterior com a artéria residual, foi constatada em apenas 10 por cento dos casos estudados. Presença de pedículo vascular duplicado ao nível da perfuraçao do septo intermuscular lateral do braço foi observada em 10 por cento dos casos; contudo, apenas um único pedículo nutria o retalho. Registrou-se divisao constante da artéria colateral em anterior e posterior, divisao da artéria colateral radial posterior em dois ramos em 100 por cento dos casos, com um ramo para porçao distal do úmero e músculos tríceps. O nervo cutâneo lateral inferior do braço perfurou o tríceps em 30 por cento dos casos. O diâmetro da artéria colateral radial ao nível da perfuraçao do septo intermuscular lateral do braço mediu em média 1,5mm. O padrao fasciocutâneo do retalho mostrou ser constante. Concluiu-se da presença de variaçoes da anatomia vascular e trajeto do nervo cutâneo lateral inferior do braço, que a estimativa das dimensoes do retalho deve considerar dados antropométricos individuais; o padrao fasciocutâneo e a vascularizaçao do segmento ósseo do úmero e músculo tríceps garantem a utilizaçao do retalho do braço em sua forma composta.