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)

Advances in metabolic engineering of Escherichia coli for isoprene biosynthesis / 生物工程学报

As an important industrial chemical, isoprene is mainly used as a precursor for synthetic rubbers. In addition, it also has wide applications in the field of pharmaceutical and chemical intermediates, food, adhesives and aviation fuel. Compared with conventional petrochemical routes, production of isoprene in microbial systems has been the research focus considering environment friendly and sustainable development features. This article summarizes the metabolic pathways and key enzymes of isoprene biosynthesis, reviews current methods and strategies in improving isoprene production of Escherichia coli, and also gives some basic ideas and expectation.

Extracellular signal-regulated kinase signaling pathway regulates the endothelial differentiation of periodontal ligament stem cells / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the effect of extracellular signal-regulated kinase (ERK) signaling pathway on the endothelial differentiation of periodontal ligament stem cells (PDLSC).</p><p><b>METHODS</b>Human PDLSC was cultured in the medium with vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (b-FGF) to induce endothelial differentiation. Endothelial inducing cells was incubated with U0126, a specific p-ERK1/2 inhibitor. PDLSC from one person were randomly divided into four groups: control group, endothelial induced group, endothelial induced+DMSO group and endothelial induced+U0126 group. The protein expression of the p-EKR1/2 was analyzed by Western blotting at 0, 1, 3, 6 and 12 hours during endonthelial induction. The mRNA expressions of CD31, VE-cadherin, and VEGF were detected by quantitative real-time reverse transcriptase polymerase chain reaction (qRT-PCR) after a 7-day induction. The proportion of CD31(+) to VE-cadherin(+) cells was identified by flow cytometry, and the ability of capillary-like tubes formation was detected by Matrigel assay after a 14-day induction. The measurement data were statistically analyzed.</p><p><b>RESULTS</b>Phosphorylated ERK1/2 protein level in PDLSC was increased to 1.24±0.12 and 1.03±0.24 at 1 h and 3 h respectively, during the endothelial induction (P<0.01). The mRNA expressions of CD31 and VEGF in induced+U0126 group were decreased to 0.09±0.18 and 0.49±0.17, which were both significantly different with those in induced group (P<0.05). The proportion of CD31(+) to VE-cadherin(+) cells of induced+U0126 group were decreased to 5.22±0.85 and 3.56±0.87, which were both significantly different with those in induced group (P<0.05). In Matrigel assay, the branching points, tube number and tube length were decreased to 7.0±2.7, 33.5±6.4, and (15 951.0±758.1) pixels, which were all significantly different with those in induced group (P<0.05).</p><p><b>CONCLUSIONS</b>The endothelial differentiation of PDLSC is positively regulated by ERK signaling pathway. Inhibition of ERK1/2 phosphorylation could suppress endothelial differentiation of PDLSC.</p>

Prevalência de dor crônica e sua associação com a situação sociodemográfica e atividade física no lazer em idosos de Florianópolis, Santa Catarina: estudo de base populacional / Prevalence of chronic pain and its association with the sociodemographic situation and physical activity in leisure of elderly in Florianópolis, Santa Catarina: population-based study

OBJETIVO: Estimar a prevalência de dor crônica e sua associação com a situação socioeconômica, demográfica e atividade física no lazer em idosos. MÉTODOS: Este estudo é parte do inquérito epidemiológico e transversal de base populacional e domiciliar EpiFloripa Idoso 2009-2010 realizado com 1.705 idosos (≥ 60 anos), residentes em Florianópolis, Santa Catarina. A partir da resposta afirmativa de dor crônica, foram investigadas as associações com as variáveis obtidas por meio de entrevista estruturada. Realizou-se a estatística descritiva, incluindo cálculos de proporções e intervalos de confiança 95% (IC95%). Na análise bruta e ajustada, empregou-se regressão de Poisson, estimando-se as razões de prevalência, com intervalos de confiança de 95% e valores p ≤ 0,05. RESULTADOS: Dentre os idosos investigados, 29,3% (IC95% 26,5 - 32,2) relataram dor crônica. Na análise ajustada, observou-se que as variáveis sexo feminino, menor escolaridade e pior situação econômica ficaram associadas significativamente com maior prevalência de dor crônica; ser fisicamente ativo no lazer ficou associado significativamente com menor prevalência do desfecho. CONCLUSÕES: Percebe-se que a dor crônica é um agravo que acomete considerável parcela de idosos, havendo desigualdades sociais na sua frequência e sendo beneficamente afetada pela atividade física no lazer. É necessário que políticas públicas de saúde subsidiem programas multidisciplinares de controle da dor incluindo a prática regular de atividade física, voltada especificamente à promoção da saúde do idoso, evitando assim que a dor crônica comprometa a qualidade de vida desta população. .

OBJECTIVE: To estimate the prevalence of chronic pain and its association with socioeconomic and demographic status, and leisure physical activity in the elderly population. METHODS: This study is part of an epidemiological cross-sectional population-based household survey called EpiFloripa Elderly 2009-2010, which was conducted with 1,705 elderly individuals (≥ 60 years) residents of Florianópolis, Santa Catarina. From the positive response to chronic pain, the associations with the variables were investigated through a structured interview. Descriptive statistics were conducted, including ratio calculation and 95% confidence intervals. In crude and adjusted analysis, Poisson regression was utilized, estimating prevalence ratios, with 95% confidence intervals and ≤ 0.05 p-values. RESULTS: Among the subjects, 29.3% (IC95% 26.5 - 32.2) reported chronic pain. Adjusted analysis showed that being female, having less years of schooling, and being in worse economic situation were significantly associated with a higher prevalence of chronic pain. Being physically active during leisure time was significantly associated with lower prevalence of the outcome. CONCLUSIONS: Therefore, it is clear that chronic pain affects a considerable amount of elderly individuals. Social inequalities are a harmful influence in these individuals' quality of life, inasmuch as those inequalities increase the frequency with which chronic pain afflicts them. At the same time, physical activity during leisure time decreases chronic pain frequency. It is fundamental that public health policies subsidize multidisciplinary pain management programs, which should include health targeted physical activity for the elderly, thus preventing the decrease in quality of life that chronic pain brings to this population. .

Downregulation of Aquaporin 4 Expression through Extracellular Signal-regulated Kinases1/2 Activation in Cultured Astrocytes Following Scratch-injury / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To investigate the role of extracellular signal-regulated kinase1/2 (ERK1/2) pathway in the regulation of aquaporin 4 (AQP4) expression in cultured astrocytes after scratch-injury.</p><p><b>METHODS</b>The scratch-injury model was produced in cultured astrocytes of rat by a 10-μL plastic pipette tip. The morphological changes of astrocytes and lactate dehydrogenase (LDH) leakages were observed to assess the degree of scratch-injury. AQP4 expression was detected by immunofluorescence staining and Western blot, and phosphorylated-ERK1/2 (p-ERK1/2) expression was determined by Western blot. To explore the effect of ERK1/2 pathway on AQP4 expression in scratch-injured astrocytes, 10 µmol/L U0126 (ERK1/2 inhibitor) was incubated in the medium at 30 min before the scratch-injury in some groups.</p><p><b>RESULTS</b>Increases in LDH leakage were observed at 1, 12, and 24 h after scratch-injury, and AQP4 expression was reduced simultaneously. Decrease in AQP4 expression was associated with a significant increase in ERK1/2 activation. Furthermore, pretreatment with U0126 blocked both ERK1/2 activation and decrease in AQP4 expression induced by scratch-injury.</p><p><b>CONCLUSION</b>These results indicate that ERK1/2 pathway down-regulates AQP4 expression in scratch-injured astrocytes, and ERK1/2 pathway might be a novel therapeutic target in reversing the effects of astrocytes that contribute to traumatic brain edema.</p>

Improving isoprene production by engineered heterologous mevalonate pathway in Escherichia coli / 生物工程学报

Isoprene is an important precursor of synthetic rubber material. In our previous study, metabolic engineered Escherichia coli strain (BW-01) was constructed and used to produce isoprene. Based on the theory of protein budget, using synthetic biology strategies including the increased copy number of genes and rare codons, we regulated the expression of key enzyme to improve isoprene production in Escherichia coli strain. Under shake-flask conditions, isoprene productivity of the engineered strain (BW-07) increased by 73% compared with BW-01, reached 761.1 mg/L. It provides a reference for further studies.

Epidemiology of cervical cancer in Colombia / Epidemiología del cáncer cervical en Colombia

Objective. To describe the incidence, mortality, time trends and prognostic factors for cervical cancer in Cali, Colombia, and to review the molecular epidemiological evidence showing that HPV is the major and necessary cause of cervical cancer and the implications of this discovery for primary and secondary prevention. Materials and methods. Incidence rates of cervical cancer during a 45-year period (1962-2007) were estimated based on the population-based cancer registry of Cali and the mortality statistics from the Municipal Health Secretariat of Cali. Prognostic factors were estimated based on relative survival. Review of the molecular epidemiological evidence linking HPV to cervical cancer was focused on the studies carried out in Cali and in other countries. Results. Incidence rates of squamous cell carcinoma (SCC) declined from 120.4 per 100 000 in 1962-1966 to 25.7 in 2003-2007 while those of adenocarcinoma increased from 4.2 to 5.8. Mortality rates for cervical cancer declined from 18.5 in 1984-1988 to 7.0 per 100 000 in 2009-2011. Survival was lower in women over 65 years of age and in clinical stages 3-4. Review of the molecular epidemiological evidence showed that certain types of HPV are the central and necessary cause of cervical cancer. Conclusions. A decline in the incidence and mortality of SCC and an increase in the incidence of adenocarcinoma during a 45-year period was documented in Cali, Colombia.

Objetivos. Describir la tendencia temporal de la incidencia, mortalidad y los factores pronósticos del cáncer de cuello uterino en Cali, Colombia, y revisar la evidencia epidemiológica molecular que muestra que el VPH es la causa principal y necesaria del cáncer cervical y las implicaciones de este descubrimiento para la prevención primaria y secundaria. Material y métodos. Se estimaron las tasas de incidencia de cáncer de cuello uterino durante un periodo de 45 años (1962-2007) con la información del registro poblacional de cáncer de Cali y las de mortalidad con las estadísticas de la Secretaría de Salud Municipal de Cali. Los factores pronósticos se estimaron sobre la base de la supervivencia relativa. La revisión de la evidencia epidemiológica molecular que une el VPH con el cáncer cervical se centró en los estudios llevados a cabo en Cali y en otros países. Resultados. Las tasas de incidencia de carcinoma de células escamosas (SCC) por 100000 se redujeron desde 120.4 en 1962-66 a 25.7 en 2003-07, mientras que las de adenocarcinoma aumentaron desde 4.2 hasta 5.8. Las tasas de mortalidad por cáncer de cuello uterino por 100000 se redujeron desde 18.5 en 1984-88 a 7.0 en 2009-11. La supervivencia fue menor en las mujeres de más de 65 años de edad y en los estadios clínicos 3-4. La revisión de la evidencia epidemiológica molecular mostró que ciertos tipos de VPH son la causa central y necesaria del cáncer cervical. Conclusiones. Se documentó la disminución de la incidencia y la mortalidad por SCC y un aumento en la incidencia de adenocarcinoma durante un periodo de 45 años en Cali, Colombia.

Incidencia, mortalidad y supervivencia al cáncer de próstata en Cali, Colombia, 1962-2011 / Prostate cancer in Cali, Colombia, 1962-2011: incidence, mortality and survival

Objetivo. Analizar la tendencia de las tasas de incidencia, mortalidad y supervivencia al cáncer de próstata (CP) en el periodo 1962-2011. Material y métodos. Con base en el Registro Poblacional de Cáncer en Cali (Colombia) y los registros de mortalidad de la Secretaría de Salud Pública Municipal se analizaron las tendencias de las tasas de incidencia, mortalidad y supervivencia por CP en Cali durante el periodo 1962-2011. Resultados. La incidencia de cáncer de próstata aumentó vertiginosamente entre 1986 y 2002 (Annual Percent Change APC 6.2%) y se estabilizó posteriormente. La mortalidad disminuyó desde 1997 en los mayores de 70 años, mientras que en el grupo de 50-69 años fue a partir de 1981. La supervivencia relativa a cinco años fue 69.8% (IC95% 67.5-72.0) y se asoció de manera significativa con la edad, periodo de diagnóstico y estrato socioeconómico. Conclusión. El incremento en la incidencia del CP coincide temporalmente con la implementación del antígeno específico de próstata (PSA por sus siglas en inglés) en Cali; hay evidencia de mejoría en la supervivencia en el CP y disminución en su mortalidad.

Objective. To analyze the trend in prostate cancer survival, incidence and mortality rates in Cali, Colombia from 1962 to 2011. Materials and methods. Based on the Cancer Registry of Cali, Colombia and the mortality registry of the City's Public Health Secretary, incidence, mortality age-standardized rates and relative survival were calculated during 1962-2011. Results. Prostate cancer incidence rates increased sharply between 1986 and 2002 (APC: 6.21%) and then leveled off. Mortality diminished in 1997 in men older than 70 years-old while in men aged 50-69 years declined since 1981. The 5-year-relative-survival was 69.8% (CI95% 67.5-72.0) and it was significantly associated with age, quinquennial period of diagnosis and socioeconomic strata. Conclusion. The increase in incidence rates of prostate cancer in time coincides with the implementation of the PSA in Cali. There is evidence of improvement in prostate cancer survival, and decreased prostate cancer mortality.

Incidencia, mortalidad y supervivencia por cáncer colorrectal en Cali, Colombia, 1962-2012 / Colorectal cancer incidence, mortality and survival in Cali, Colombia, 1962-2012

Objetivo. Estudiar el comportamiento del cáncer colorrectal (CCR) en Cali, Colombia, durante el periodo 1962-2012, utilizando la información del Registro Poblacional de Cáncer de Cali y de la Secretaría de Salud Municipal de Cali. Material y métodos. Análisis ecológico de series de tiempo para estudiar la tendencia de las tasas de incidencia (1962-2007) y mortalidad por CCR (1984-2012); y un análisis de supervivencia de la serie de casos de CCR registrados en Cali entre 1995-2004. La tendencia temporal de las tasas de incidencia (TIEE) y mortalidad (TMEE) estandarizadas por edad se estudió mediante el cambio medio anual (APC por sus siglas en inglés). Se estimó la supervivencia relativa a cinco años y se hizo un análisis múltiple mediante el modelo de regresión de riesgos proporcionales de Cox. Resultados. Durante el periodo 1962-2007, las TIEE de CCR aumentaron en los hombres y mujeres residentes en Cali; APC= 2.6 (IC95% 2.2-3.0) y APC= 2.2% (IC95% 1.8-2.7), respectivamente. Entre 1984-2012 las TMEE permanecieron estables en las mujeres y en los hombres aumentaron en todos los grupos de edad; APC=1.8 (IC95% 0.8-2.8). La supervivencia relativa a cinco años fue independiente del sexo y aumentó de 29.7% en 1995-1999 a 39.8% durante 2000-2004. El riesgo de morir por CCR fue mayor en las personas de estratos socioeconómicos (ESE) bajos frente a los ESE altos, HR= 2.1 (IC95% 1.7-2.6); en los mayores de 70 años frente a los <50, HR= 2.4 (IC95% 1.9-2.9) y en el periodo 1995-1999 frente al 2000-2004 HR=1.5 (IC95% 1.3-1.7). Conclusión. El cáncer de colon y recto está ocupando un lugar preponderante entre los cánceres de mayor importancia en Cali, Colombia.

Objective. To study the colorectal cancer (CRC) behavior in Cali, Colombia, during the 1963-2012 period using data from the Population-based Cancer Registry of Cali and the Municipal Health Secretariat of Cali. Materials and methods. An ecological time series analysis to study the CRC incidence (1962-2007) and mortality (1984-2012) rate trends; and a survival analysis of CRC cases registered in Cali between 1995 and 2004 were conducted. The age-standardized temporal trend of incidence (I-ASR) and mortality (M-ASR) rates were studied using an annual percent change (APC). The 5-year relative survival was estimated and a multivariate analysis was performed using the Cox proportional hazard regression model. Results. During the 1962-2007 period, CRC TTIR increased in men and women living in Cali [APC= 2.6 (95% CI 2.2-3.0) and APC= 2.2% (95% CI 1.8-2.7), respectively]. In the 1984-2012 period, the TTMR remained stable in women but increased in men in all age groups [APC= 1.8 (95% CI 0.8-2.8)]. The 5-year relative survival was independent of sex and increased from 29.7% in 1995-1999 to 39.8% in 2000-2004. The risk of dying from CRC was higher in people of lower socio-economic status (SES) vs higher SES [HR= 2.1 (95% CI: 1.7-2.6)], among people older than 70 years of age vs younger than 50 years [HR= 2.4 (95% CI: 1.9-2.9)], and for the 1995-1999 period vs 2000-2004 period [HR= 1.5 (95% CI 1.3-1.7)]. Conclusion. CRC is beginning to take a prominent place among the most important cancers in Cali, Colombia.

Cost analysis of different cervical cancer screening strategies in Mexico / Análisis de costos de distintas estrategias de tamizaje para cáncer cervical en México

Objective. To compare the costs and number of undetected cases of four cervical cancer screening strategies (CCSS) in Mexico. Materials and methods. We estimated the costs and outcomes of the following CCSS: a) conventional Papanicolaou smear (Pap) alone; b) high-risk human papilloma virus testing (HR-HPV) as primary screening with Pap as reflex triage; c) HR-HPV as primary screening with HPV-16/18 typing, liquid-based cytology (LBC) and immunostaining for p16/Ki67 testing as reflex triage, and d) co-testing with HR-HPV and LBC with HPV-16/18 typing and immunostaining for p16/Ki67 as reflex triage. The outcome of interest was high-grade cervical lesions or cervical cancer. Results. HR-HPV testing, HPV typing, LBC testing and immunostaining is the best alternative because it is the least expensive option with an acceptable number of missed cases. Conclusions. The opportunity costs of a poor quality CCSS is many false negatives. Combining multiple tests may be a more cost-effective way to screen for cervical cancer in Mexico.

Objetivo. Comparar los costos y los casos no detectados de cuatro estrategias de tamizaje de cáncer cervical (ETCC) en México. Material y métodos. Se estimaron los costos y resultados en salud de las siguientes ETCC: a) citología convencional como único procedimiento de tamizaje; b) detección de virus del papiloma humano de alto riesgo (VPH-AR) como tamizaje primario y citología convencional como procedimiento de triage; c) detección de VPH-AR como tamizaje primario y tipificación de VPH-16/18, citología en base líquida e inmunotinción para p16/Ki67 como procedimientos de triage, y d) evaluación conjunta con VPH-AR y citología en base líquida como tamizaje primario y tipificación de VPH-16/18 e inmunotinción para p16/Ki67 como procedimientos de triage. El resultado en salud analizado fueron los casos de neoplasia intraepitelial cervical (CIN 2/3) o cáncer cervical detectados. Resultados. La ETCC basada en la detección de VPH-AR como prueba primaria y seguida de la tipificación de VPH-16/18, la citología en base líquida y la inmunotinción para p16/Ki67 como procedimientos de triage es la mejor alternativa, ya que es la menos costosa y la que tuvo un nivel aceptable de casos perdidos. Conclusiones. El costo de oportunidad de una ETCC de mala calidad es un alto número de falsos negativos. La combinación seriada de varias pruebas de tamizaje y triage puede ser una alternativa costo-efectiva para la detección oportuna de cáncer cervical en México.

Dieta y cáncer gástrico en México y en el mundo / Diet and gastric cancer in Mexico and in the world

El cáncer gástrico (CG) es la cuarta causa de muerte por cáncer a nivel global. La dieta y el consumo de alcohol y tabaco, además de la infección por Helicobacter pylori determinan un gran número de casos de esta neoplasia. Algunos alimentos contienen sustancias que podrían influir en el proceso de carcinogénesis gástrica, aunque los mecanismos subyacentes no están completamente dilucidados. En México y el mundo, la disminución en el consumo de frutas, vegetales no feculentos y allium, leguminosas y alimentos fuente de selenio, así como el aumento en el consumo de sal, alimentos salados, salmuera y ahumados, chile, carnes procesadas y asadas o a la parrilla se han asociado respectivamente con un aumento de riesgo de CG. Con la evidencia disponible, se podrían desarrollar y evaluar programas para la prevención y control del CG.

Gastric cancer (GC) is the fourt leading cause of cancer death at global level. Diet, alcohol and tobacco, in addition to Helicobacter pylori infection, account for a large number of cases. Some substances contained in foods may influence GC carcinogenesis process; however, the underlying mechanisms have not been fully elucidated. In Mexico and worldwide, a low intake of fruits, non-starchy and allium vegetables, pulses, and foods containing selenium, as well as high intake of salt, salty, salted and smoked foods, chili pepper, processed and grilled/barbecued meats, have been respectively associated with an increased risk of GC. Based on the available evidence, programs for GC prevention and control could be developed and evaluated.

Method development and validation for determining 1,3-butadiene in human blood by gas chromatography-mass spectrometry and head-space gas chromatography / 法医学杂志

To develop a simple, validated method for identifying and quantifying 1,3-butadiene (BD) in human blood by gas chromatography-mass spectrometry (GC-MS) and head-space gas chromatography (HS-GC). BD was identified by GC-MS and HS-GC, and quantified by HS-GC. The method showed that BD had a good linearity from 50 to 500 microg/mL (r > 0.99). The limits of detection and quantification were 10 microg/mL and 50 microg/mL, respectively. Both the intra-day precision and inter-day precision were < 6.08%, and the accuracy was 96.98%-103.81%. The method was applied to an actual case, and the concentration of BD in the case was 242 microg/mL in human blood. This simple method is found to be useful for the routine forensic analysis of acute exposure to BD.

Regulation of isoprenoid pathway for enhanced production of linalool in Saccharomyces cerevisiae / 生物工程学报

Linalool is an important monoterpene, and widely used in food, pharmaceutical and cosmetic industry. The low concentration in plants and the difficulties in extraction restrict its large scale production. Saccharomyces cerevisiae can provide the monoterpene precursor, geranyl diphosphate (GPP) through its endogenous isoprenoid pathway. Therefore, it could be used as the host for monoterpene production. However, the weak metabolic flux through the isoprenoid pathway leads to the insufficient supply of GPP, and results in low monoterpene productivity. In order to increase the metabolic flux, we constructed the integrated expression plasmid pRS305-tHMG1 and free expression plasmid pYLIS-IDI1 to enhance the expression levels of isopentenyl diphosphate isomerase (IDI1) and a truncated 3-hydroxyl-3-methylglutaryl-CoA reductase gene (tHMG1). The two plasmids were separately transformed into S. cerevisiae CEN.PK2-1C, resulting in strains LS01 and LS02. The plasmid pYLIS-IDI1 was further transformed into strain LS01, resulting in strain LS03. GC-MS analysis showed that the linalool concentration was increased by 1.3 times and reached (127.71 +/- 7.68) microg/L. In conclusion, enhancement of the supply of GPP precursors through the regulation of isoprenoid pathway could increase the linalool production in S. cerevisiae.

Effects of U0126 on growth and activation of mitogen-activated protein kinases in Aspergillus fumigatus / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Invasive aspergillosis (IA), which is mainly caused by Aspergillus fumigatus (A. fumigatus), is a major cause of morbidity and mortality in immunocompromised patients. Despite considerable progress in currently available antifungals the mortality still remains high in critically ill patients. U0126 which is a highly selective inhibitor of MEK1 and MEK2 in the RAF/MEK/ERK pathway in mammalian cells has been demonstrated to have an anti-proliferative role in cancer cells. The purpose of this study was to explore the role of U0126 on growth inhibition and activation of mitogen-activated protein kinases (MAPKs) in A. fumigatus.</p><p><b>METHODS</b>Germination percentage and hyphae growth in A. fumigatus treated with U0126 were observed and compared with untreated controls. Western blotting analysis was used to detect changes in activation of SakA, MpkA and MpkB.</p><p><b>RESULTS</b>U0126 inhibited germination and hyphae growth in A. fumigatus and enhanced the phosphorylation of SakA and MpkA under oxidative stress. U0126 at 10 µmol/L did not block the activation of MpkB during nitrogen starvation stress.</p><p><b>CONCLUSION</b>U0126 shows promise as an antifungal candidate and the MAPK pathway may be a possible antifungal drug target for A. fumigatus.</p>

Efficacy of combination treatment of the inhibitor of phosphatidyl inositol-3-kinase/protein kinase B pathway BEZ235 and the inhibitor of extracellular regulated protein kinase/mitogen-activated protein kinase pathway U0126 in a tumor cell model / 中国医学科学院学报

<p><b>OBJECTIVE</b>To study the inhibitory effect of the dual usage of BEZ235 and U0126, the inhibitor of phosphatidyl inositol-3-kinase/protein kinase B pathway and extracellular regulated proteinkinase/mitogen-activated protein kinase pathway, respectively, on cell proliferation.</p><p><b>METHODS</b>Phosphatase and tensin homolog knockout mouse embryonic fibroblast (PTEN-/-MEF) cell lines were used as the cellular model for malignant tumors. BEZ235, the dual inhibitor of phosphatidyl inositol-3-kinase and mammalian target of rapamycin, and U0126, the inhibitor of mitogen-activated protein kinase were used to treat the cells individually and in a combination manner. The inhibitory effects to cell proliferation were monitored by MTT.</p><p><b>RESULTS</b>Both BEZ235 and U0126 suppressed PTEN knockout cell proliferation, and their half inhibitory concentrations were 6.257 nmol/L and 22.85 μmol/L, respectively. However, the combination treatment of the two drugs showed antagonistic rather than synergistic effect on cell proliferation.</p><p><b>CONCLUSION</b>BEZ235 and U0126 are not suitable for a combined target therapy regimen.</p>

EGFR-ERK signaling pathway down-regulates miRNA-145 in lung cancer cells / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To investigate the relationship between EGFR activation and down-regulation of miRNA-145 in lung cancer.</p><p><b>METHODS</b>Normal human lung epithelia cell line (BEAS-2B), human lung adenocarcinoma cell lines with wild-type EGFR (A549 and H292) and human lung adenocarcinoma cell lines with EGFR mutation (H1975 and H1650) were chosen in this study. The levels of miRNA-145 and p-EGFR were determined by quantitative real-time PCR (qRT-PCR) and Western blotting, respectively, and the relationship between p-EGFR and miRNA-145 levels was analyzed. The miRNA-145 levels were determined by qRT-PCR after activating EGFR with EGF or blocking EGFR signal pathway with AG1478. In addition, ERK1/2 inhibitor U0126 was used to inhibit ERK1/2 activation and then the expression of miRNA-145 was detected.</p><p><b>RESULTS</b>The miRNA-145 levels were closely negatively related with p-EGFR in lung cancer cells (r = -0.926, P = 0.024). EGF down-regulated miRNA-145 expression, particularly in BEAS-2B cells (53.0%; t = 30.993, P = 0.001) and A549 cells (42.6%; t = 14.326, P = 0.005).The miRNA-145 was up-regulated after inhibiting p-EGFR with AG1478, and significantly enhanced by 67.5% in H1975 cells when treated with AG1478 (t = 8.269, P = 0.014). The ERK1/2 signal pathway was activated by p-EGFR. U0126 restored the miRNA-145 down-regulation induced by EGFR-activation in lung cancer cells.</p><p><b>CONCLUSION</b>The activation of EGFR down-regulates miRNA-145 expression through ERK1/2 in lung cancer cells.</p>