Functional synergism of pyoverdine and the S-type pyocins of Pseudomonas aeruginosa / 生物工程学报

Pyocin S2 and S4 in Pseudomonas aeruginosa use the same uptake channels as the pyoverdine does in bacteria, indicating a possible connection between them. In this study, we characterized the single bacterial gene expression distribution of three S-type pyocins (Pys2, PA3866, and PyoS5) and examined the impact of pyocin S2 on bacterial uptake of pyoverdine. The findings demonstrated that the expression of the S-type pyocin genes was highly differentiated in bacterial population under DNAdamage stress. Moreover, exogenous addition of pyocin S2 reduces the bacterial uptake of pyoverdine so that the presence of pyocin S2 prevents the uptake of environmental pyoverdine by non-pyoverdine synthesizing 'cheaters', thereby reducing their resistance to oxidative stress. Furthermore, we discovered that overexpression of the SOS response regulator PrtN in bacteria significantly decreased the expression of genes involved in the synthesis of pyoverdine, significantly decreasing the overall synthesis and exocytosis of pyoverdine. These findings imply a connection between the function of the iron absorption system and the SOS stress response mechanism in bacteria.

Long non-coding RNA LINC01268 promotes cell growth and inhibits cell apoptosis by modulating miR-217/SOS1 axis in acute myeloid leukemia

The aim of this study was to evaluate the pathogenic role of newly identified long non-coding (lnc)-RNA LINCO1268 in acute myeloid leukemia (AML), and investigate its therapeutic potential. The expression level of LINC01268 in AML was measured by quantitative PCR (qPCR). The viability, cell cycle progression, and apoptosis of AML cells were measured by CCK-8 assay and flow cytometry, respectively. The interaction between LINC01268 and miR-217 were predicted by the miRDB website, and then verified by luciferase reporter assay and RNA immunoprecipitation (RIP) assay. The relationship between miR-217 and SOS1 was predicted by TargetScan website, and verified by luciferase reporter assay. LINC01268 was significantly upregulated by 1.6 fold in bone marrow samples of AML patients, which was associated with poor prognosis. LINC01268 was also significantly upregulated in AML cells. LINC01268 knockdown inhibited viability and cell cycle progression but promoted apoptosis of AML cells. Furthermore, LINC01268 functioned as a ceRNA via competitively binding to miR-217, and SOS1 was identified as a target of miR-217. Moreover, LINC01268 positively regulated SOS1 expression to promote AML cell viability and cell cycle progression but inhibited apoptosis via sponging miR-217. LINC01268 promoted cell growth and inhibited cell apoptosis through modulating miR-217/SOS1 axis in AML. This study offers a novel molecular mechanism for a better understanding of the pathology of AML. LINC01268 could be considered as a potential biomarker for the therapy and diagnosis of AML.

Predictores de mortalidad en pacientes con sepsis obstétrica mediante uso de score de sepsis obstétrica y evaluación secuencial de falla orgánica-obstétrica / Predictors of mortality in patients with obstetric sepsis using sepsis obstetric score and sequential organ failure assessment-obstetrics / Preditores de mortalidade em pacientes com sepse obstétrica usando Escore de Sepse Obstétrica e Avaliação Seqüencial de Falha Orgânico-Obstétrica

Resumen: Objetivo: Determinar los predictores de mortalidad en pacientes con sepsis obstétrica mediante score de sepsis obstétrica (SOS) y evaluación secuencial de falla orgánica-obstétrica (SOFA-O). Material y métodos: Se realizó un estudio observacional, retrospectivo, descriptivo, donde se recabaron los datos de pacientes que ingresaron a una Unidad de Cuidados Intensivos de hospitales de segundo nivel, en el periodo 30 de junio de 2015 al 30 de junio de 2017 y que tuvieron diagnóstico de sepsis obstétrica, donde se aplicaron instrumentos mediante escala SOS y SOFA-O, correlacionándose las variables con mortalidad materna. Resultados: De un universo de 284 pacientes que ingresaron a UCI de Hospitales de segundo nivel se seleccionaron 51, quienes tenían criterios de inclusión para sepsis, correlacionándose con variables de escala de SOS y SOFA-O, encontrando como mayor factor de riesgo para el desarrollo de sepsis ser multigesta, tener preeclampsia, anemia, cesárea, mal control prenatal y tener procedimientos invasivos. Las variables cuantitativas relacionadas con muerte materna fueron creatinina, relación PaO2/FiO2, frecuencia cardiaca, lactato, saturación venosa, con un puntaje de SOS mínimo y máximo para muerte materna (7-22) y para SOFA-O (10-18) puntos. Hubo una mortalidad de 7.8% (cuatro pacientes) de la población estudiada. Conclusiones: La incidencia de sepsis obstétrica se encuentra en aumento, por lo que el reconocimiento rápido de ésta y la terapia adecuada impactarán en la supervivencia de la paciente.

Abstract: Objective: To determine the predictors of mortality in patients with obstetric sepsis using Sepsis Obsessional Score (SOS) and Sequential Organ Failure Assessment-Obstetric (SOFA-O). Material and methods: An observational, retrospective, descriptive study was carried out, where data were collected from patients who entered an intensive care unit of second level hospitals in the period June 30 2015, to June 30 2017, who had a diagnosis of sepsis Obstetric, where SOS and SOFA-O instruments were applied, correlating the variables with maternal mortality. Results: From a universe of 284 patients who entered the ICU of second level hospitals, 51 patients were selected who had inclusion criteria for sepsis, correlating with SOS and SOFA-O scale variables, finding it to be a major risk factor for development of sepsis being multigested, having preeclampsia, anemia, cesarean section, prenatal poor control and having invasive procedures, the quantitative variables related to maternal death were: creatinine, PaO2/FiO2 ratio, heart rate, lactate, venous saturation. With a minimum and maximum SOS score for maternal death (7-22) and SOFA-O (10-18) points. There was a mortality of 7.8% (four patients) of the study population. Conclusions: The incidence of obstetric sepsis is increasing, so rapid recognition and appropriate therapy will impact patient survival.

Resumo: Objetivo: Determinar os preditores de mortalidade em pacientes com sepse obstétrica pelo Escore de Sepse Obstétrica (S.O.S.) e Avaliação Seqüencial de Falha Orgânico-Obstétrica (SOFA-O). Material e métodos: Foi realizado um estudo observacional, retrospectivo, descritivo, onde foram coletados dados de pacientes internados em uma unidade de terapia intensiva no período de 30 de junho de 2015 a 30 de junho de 2017 com diagnóstico de sepse obstétrica, onde foram aplicados instrumentos utilizando escalas S.O.S e SOFA-O, correlacionando as variáveis com a mortalidade materna. Resultados: De um universo de 284 pacientes internados na UTI, foram selecionados 51 pacientes que possuíam critérios de inclusão para sepse, correlacionando com as variáveis S.O.S e SOFA-O, encontrando como um importante fator de risco para o desenvolvimento da sepse ser multigesta, apresentar pré-eclâmpsia, anemia, cesárea, controle pré-natal deficiente e procedimentos invasivos. As variáveis quantitativas relacionadas ao óbito materno foram creatinina, relação PaO2/FiO2, frequência cardíaca, lactato, saturação venosa. Com um escore de S.O.S mínimo e máximo para morte materna (7-22) e para SOFA-O (10-18). Houve uma mortalidade de 7.8% (4 pacientes) da população estudada. Conclusões: A incidência de sepse obstétrica está aumentando, portanto o reconhecimento rápido e a terapia adequada terão impacto na sobrevida do paciente.

Predictores de la mortalidad en pacientes con sepsis obstétrica mediante el uso de una puntuación de sepsis obstétrica y evaluación secuencial de falla orgánica-obstétrica / Predictors of mortality in patients with obstetric sepsis using the Sepsis in Obstetrics Score and Sequential Organ Failure Assessment-Obstetrics / Preditores da mortalidade em pacientes com sepse obstétrica usando escore de sepse obstétrica e evaluação sequencial da falha orgânica obstétrica

Resumen Objetivo Determinar los predictores de mortalidad en pacientes con sepsis obstétrica mediante puntuación de sepsis obstétrica (SOS) y evaluación secuencial de falla orgánica-obstétrica (SOFA-O). Material y métodos Se realizó un estudio observacional, retrospectivo, descriptivo, donde se recabaron los datos de las pacientes que ingresaron a unidades de cuidados intensivos de hospitales de segundo nivel con diagnóstico de sepsis obstétrica en el periodo del 30 de junio de 2015 al 30 de junio de 2017; se aplicaron los instrumentos SOS (sepsis en obstetricia) y SOFA-O (evaluación secuencial de falla orgánica-obstétrica), y se correlacionaron las variables con la mortalidad materna. Resultados De un universo de 284 pacientes que ingresaron a las UCI de hospitales de segundo nivel, se seleccionaron 51 que tenían criterios de inclusión para sepsis, correlacionándose con variables de las escalas SOS y SOFA-O. Se encontró como mayor factor de riesgo para el desarrollo de sepsis ser multigesta, tener preeclampsia, anemia, cesárea, mal control prenatal y haber sido sometida a procedimientos invasivos. Las variables cuantitativas relacionadas con muerte materna fueron creatinina, relación PaO2/FiO2, frecuencia cardiaca, lactato, saturación venosa. El puntaje de SOS mínimo y máximo para muerte materna fue 7-22 y de SOFA-O, 10-18 puntos. Hubo una mortalidad de 7.8% (cuatro pacientes) de la población estudiada. Conclusiones La incidencia de sepsis obstétrica se encuentra en aumento, por lo que su reconocimiento rápido y la terapia adecuada impactarán en la supervivencia de la paciente.

Abstract Objective To determine the predictors of mortality in patients with obstetric sepsis using the Sepsis in Obstetrics Score (SOS) and the Sequential Organ Failure Assessment-Obstetrics (SOFA-O). Material and methods An observational, retrospective, descriptive study was carried out, where data were collected from patients who entered intensive care units of second-level hospitals with a diagnosis of obstetric sepsis in the period from June 30, 2015 to June 30, 2017. The SOS and SOFA-O instruments were applied, correlating the variables with maternal mortality. Results From a universe of 284 patients who entered the ICU of second level hospitals, 51 were selected who had inclusion criteria for sepsis, correlating with SOS and SOFA-O variables. We found that major risk factors for the development of sepsis were multigestation, having preeclampsia, anemia, cesarean section, poor prenatal control and been subject of invasive procedures. The quantitative variables related to maternal death were creatinine, PaO2/FiO2 ratio, heart rate, lactate, venous saturation. The minimum and maximum SOS scores for maternal death were 7-22, and SOFA-O, 10-18 points. There was a mortality of 7.8% (four patients) of the study population. Conclusions The incidence of obstetric sepsis is increasing; therefore, rapid recognition and appropriate therapy will impact patient's survival.

Resumo Objetivo Determinar os preditores de mortalidade em pacientes com sepse obstétrica por meio do escore de sepse obstétrica (S.O.S) e Avaliação Sequencial da falha orgânica-obstétrica (SOFA-O). Material e métodos Foi realizado um estudo observacional, retrospectivo e descritivo, onde foram coletados dados de todas as pacientes que ingressaram na unidade de terapia intensiva, no período de 30 de junho de 2015 a 30 de junho de 2017, com diagnóstico de sepse obstétrica, onde foram aplicadas escalas S.O.S e SOFA-O, correlacionando as variáveis com a mortalidade materna. Resultados De um universo de 284 pacientes que ingressaram na UTI, selecionaram-se 51 pacientes que apresentaram critérios de inclusão para sepse, correlacionando-se com variáveis de escala S.O.S e SOFA-O, encontrando como maior fator de risco para desenvolvimento da sepse ser: multigesta, apresentar pré-eclâmpsia, anemia, cesariana, controle pré-natal deficiente e procedimentos invasivos. As variáveis quantitativas relacionadas à morte materna foram: creatinina, relação PaO2/FIO2, freqüência cardíaca, lactato, saturação venosa. Com um escore mínimo e máximo de S.O.S para morte materna 7-22 e SOFA-O 10-18 pontos. Houve uma mortalidade de 7.8% (4 pacientes) da população estudada. Conclusões A incidência de sepse obstétrica está aumentando, de modo que reconhecimento rápido e uma terapia apropriada afetará a sobrevivência do paciente.

Discovery of topAp4 as a new sensing element for TNT detection / 军事医学

Objective To screen the sensing elements for TNT detection in Escherichia coli genome.Methods A genome promoter library with cutting E.coli K-12 MG1655 genome was constructed.Bacterial luciferase luxCDABE was used as a reporter gene during promoter screening.We discovered TNT sensing elements through several rounds of screen-ing.Through analysis of sensitivity, specificity and timeliness, the promoter activity of the elements was evaluated,and the functional sequence of the elements was further confirmed.Results and Conclusion We successfully constructed an E.co-li K-12 MG1655 genome library , from which a TNT sensing element was discovered,which had a good performance in the analysis of sensitivity, specificity and timeliness.In this study, we reported that the topAp4 is a TNT sensing element for the first time.We also verified its excellent promoter activity.

Caracterization of the SOS response in Leptospira interrogans sorovar Copenhageni / Caracterização da resposta SOS em Leptospira interrogans sorovar Copenhageni

Leptospira is a basal genus in an ancient group of bacteria, the spirochetes. The pathogenic species are responsible for leptospirosis, a disease with worldwide distribution and of public health importance in developed tropical countries. L. interrogans serovar Copenhageni is the agent for the majority of human leptospirosis in Brazil. In this work, we used a great variety of experimental approaches to characterize the SOS system in this serovar, to identify its impact in general DNA damage response, as well as to assess the DNA repair toolbox owned by pathogenic and saprophytic leptospires. We identified an additional repressor LexA, acquired by lateral gene transfer, exclusively in serovar Copenhageni. We also observed that UV-C irradiation led to massive death of cells and blockage of cell division in the survivors. Both repressors were active and we identified the sequences responsible for binding to promoters. However, the LexA1 SOS box was redefined after a de novo motif search on LexA1 ChIP-seq enriched sequences. This regulator was able to bind to at least 25 loci in the genome. DNA damage also caused a massive rearrangement of metabolism: increase in expression was observed in transposon and prophage genes, in addition to DNA repair pathways and mutagenesis inducers; on the other hand, motility, general metabolism and almost all virulence genes were repressed. Two induced prophages provided several proteins with useful functions. We also assessed the DNA repair-related genes presented by the three species of Leptospira: the saprophytic L. biflexa, the facultative pathogen L. interrogans and the obligatory pathogen L. borgpetersenii. There are more diversity and redundancy of repair genes in L. interrogans in comparison with the other species. Lateral gene transfer seems to be an important supplier of DNA repair functions. In addition, leptospires share characteristics of both Gram-positives and Gram-negatives bacteria. Representative genes from several different pathways were induced during infection of susceptible mice kidneys, suggesting DNA repair genes are active while causing disease. All these data suggest mobile genetic elements are the major forces in leptospiral evolution. Moreover, during DNA damage response, several SOS-dependent and independent mechanisms are employed to decrease cell growth and virulence in favor of controlled induction of mechanisms involved in genetic variability

Leptospira é um gênero basal em um grupo já considerado um dos mais ancestrais, as espiroquetas. As espécies patogênicas são responsáveis pela leptospirose, uma doença presente em todo o mundo e de principal importância em países tropicais em desenvolvimento. L. interrogans sorovar Copenhageni é o agente da maior parte dos casos no Brasil. Nesse trabalho, utilizamos diversas abordagens experimentais para caracterizar o sistema SOS nesse sorovar, identificar seu impacto na resposta geral a danos no DNA, assim como avaliar as funções de reparo de DNA disponíveis em leptospiras patogênicas e saprofíticas. Identificamos um repressor LexA adicional, adquirido por transferência horizontal e exclusivo do sorovar Copenhageni. Observamos também que irradiação por UV-C causou significativa morte celular e bloqueio da divisão celular dos sobreviventes. Ambos os repressores são ativos e identificamos as sequências que utilizam para se ligar aos promotores dos genes regulados. Entretanto, o SOS box de LexA1 foi redefinido após uma busca de novo por motivos enriquecidos nas sequências recuperadas por ChIP-seq. Esse regulador ligou-se ao menos a 25 locais do genoma. A maioria desses alvos teve aumento de expressão após UV-C. Danos no DNA também causaram um importante rearranjo metabólico: houve aumento de expressão em transposons e profagos, além de indutores de mutagênese e vias de reparo; por outro lado, mobilidade, crescimento celular e quase todos os fatores de virulência foram reprimidos. Dois profagos induzidos durante essa resposta, possivelmente proporcionam algumas proteínas de funções importantes. Nós também avaliamos a presença de genes envolvidos no reparo de DNA em três espécies de leptospira: L. biflexa, L. interrogans e L. borgpetersenii. L. interrogans é a espécie com maior diversidade e redundância de genes de reparo. Além disso, transferência horizontal parece ser um importante fornecedor de funções de reparo nesse gênero. Leptospiras também apresentam genes característicos tanto de bactérias Gram-positivas quanto Gram-negativas. Genes representando diferentes vias de reparo foram induzidos durante infecção em modelo animal, sugerindo que essas vias estão ativas no curso da doença. Todos esses dados, em conjunto, sugerem que elementos genéticos móveis são de extrema importância na evolução do gênero e das vias de reparo. Assim, durante a resposta a danos no DNA, diversos mecanismos dependentes e independentes de SOS são empregados para frear o crescimento celular e virulência em favor da indução controlada de mecanismos para aumentar variabilidade genética

Tecnología de información y comunicación y su aplicación en la educación / Information and communications technologies and their application in education

La presente revisión se realizó con el objetivo de describir los aspectos que puedan ser de ayuda para comprender la importancia de las tecnologías de información y comunicación en el campo de la educación. Se describen el concepto y las características generales de las TIC así como su utilización en el campo de la educación. Se destaca la posibilidad de desarrollar la educación a distancia, con sus, hasta ahora, insuperables ventajas, así como sus eventuales desventajas. Se señalan algunas iniciativas nacionales en este sentido y se destaca la aplicación de las tecnologías en educación en salud(AU)

This review was conducted with the objective of describing the aspects that may be of help to understand the importance of the technologies of information and communication in the field of education. Describes the concept and the general characteristics of ICT as well as their use in the field of education. Highlights the possibility of developing distance education, with its, so far, insurmountable advantages, as well as their possible disadvantages. National initiatives in this regard are designated and highlights the application of technologies in health education(AU)

Uso del balón sos bakri en atonía uterina: serie de casos en un hospital universitario de tercer nivel / SOS bakri balloon use in uterine inertia. number of cases in a university tertiary hospital

Objetivo: Describir el uso del balón SOS Bakri en el tratamiento de la hemorragia posparto vaginal por atonía uterina después de la falla del tratamiento médico. Métodos: Se presenta una serie de 15 pacientes con hemorragia posparto vaginal por atonía uterina, tratadas satisfactoriamente con taponamiento uterino con balón SOS Bakri luego de no responder a tratamiento médico ni a masaje uterino. Resultados: La edad promedio de las pacientes fue 22,7 (± 6,8) años. La edad gestacional promedio fue 36,3 (± 2,6) semanas. El balón se insertó en los primeros 30 minutos del diagnóstico de la atonía uterina. El tiempo total que permaneció el balón en útero fue de 13,6 (± 6,1) horas. La pérdida hemática posterior a la colocación del balón fue en total 265,3 (± 258,1) cm3. El balón SOS Bakri fue efectivo en 100 % de las pacientes. Ninguna de las pacientes ameritó histerectomía. Conclusiones: El balón SOS Bakri es una alternativa eficaz mínimamente invasiva, económica y de fácil acceso en la terapéutica de la AU que no responde al tratamiento médico.

Objective: To describe the use of SOS Bakri Balloon in the treatment of postpartum hemorrhage after unsuccessful medical treatment of uterine atony. Method: We describe a case series of 15 patients with severe uterine atony after vaginal delivery that were successfully managed with SOS Bakri balloon after failed uterine massage and medical treatment. Results: The mean patient age was 22.7 (± 6.8) years. The mean gestational age was 36.3 (± 2.6) weeks. The balloon was inserted within 30 minutes of diagnosis of uterine atony. The mean length of balloon placement was 13.6 (± 6.1) hours. The mean total blood loss post balloon insertion was of 265.3 (± 258.1) cm3. The SOS Bakri balloon was effective 100 % of the time. None of the patient required hysterectomy. Conclusion: Insertion of SOS Bakri balloon is a simple conservative live saving alternative in the management of postpartum uterine atony.

Application of SOS/umu in screening cytoprotectors of plants against mitomycin C-induced genotoxic damage / 中草药

Objective: To establish a system and method for screening plant extract against mitomycin C-induced genotoxic damage. Methods: Salmonella typhimurium TA1535/pSK1002 and acute toxicity experiment of mice were used, and the effects of the extracts from ten plants, Chrysanthemis Flos, Allii Bulbus, Zingiberis Rhizoma Recens, Ginkgo Folium, Ginseng Radix et Rhizoma, Vitis Viniferae Semen, Gemmae Camelliae Sinensis Folium, Ganoderma, Acanthopanacis Senticosi Radix et Rhizoma seu Caulis, and Sojae Semen, and the extract combinations on mitomycin C-induced genotoxic damage were observed by SOS/umu test. Results: Significantly protective effects of five extracts, including the extracts from Allii Bulbus, Vitis Vindferae Semen, Gemmae Camelliae Sinensis Folium, Acanthopanacis Senticosi Radix et Rhizoma seu Caulis, and Sojae Semen against mitomycin C-induced genotoxicity were observed. Acanthopanacis Senticosi Radix et Rhizoma seu Caulis extract (1.5 g/L) could inhibit the mitomycin C-induced genotoxicity (67.12%). Combinations of any two extracts showed higher antimutagenic capacity than any single one. Among all the combinations, Acanthopanacis Senticosi Radix et Rhizoma seu Caulis-Gemmae Camelliae Sinensis Folium and Acanthopanacis Senticosi Radix et Rhizoma seu Caulis-Vitis Viniferae Semen showed the highest activity, and the inhibition rate of the former against the mitomycin C-induced genotoxicity was 83.2%. In vivo tests showed that Acanthopanacis Senticosi Radix et Rhizoma seu Caulis- Gemmae Camelliae Sinensis Folium could significantly decrease the micronucleus rate and sperm abnormality rate of mice induced by mitomycin C and also increase the thymus indexes. Conclusion: Based on the results, it is clearly proved that the SOS/umu is not only a useful and convenient way to evaluate the antimutagenic ability of plant extracts, but also could be used as a kind of rapid screening model for cytoprotector with high throughput screening of candidate extracts or compounds.

The RecX protein interacts with the RecA protein and modulates its activity in Herbaspirillum seropedicae

DNA repair is crucial to the survival of all organisms. The bacterial RecA protein is a central component in the SOS response and in recombinational and SOS DNA repairs. The RecX protein has been characterized as a negative modulator of RecA activity in many bacteria. The recA and recX genes of Herbaspirillum seropedicae constitute a single operon, and evidence suggests that RecX participates in SOS repair. In the present study, we show that the H. seropedicae RecX protein (RecX Hs) can interact with the H. seropedicaeRecA protein (RecA Hs) and that RecA Hs possesses ATP binding, ATP hydrolyzing and DNA strand exchange activities. RecX Hs inhibited 90% of the RecA Hs DNA strand exchange activity even when present in a 50-fold lower molar concentration than RecA Hs. RecA Hs ATP binding was not affected by the addition of RecX, but the ATPase activity was reduced. When RecX Hs was present before the formation of RecA filaments (RecA-ssDNA), inhibition of ATPase activity was substantially reduced and excess ssDNA also partially suppressed this inhibition. The results suggest that the RecX Hs protein negatively modulates the RecA Hs activities by protein-protein interactions and also by DNA-protein interactions.

Efeitos genotóxicos e indução do SOS em mutantes derivados de Escherichia coli K-12 durante o processo de interação com superfícies bióticas e abióticas / Genotoxic and SOS induction in mutants derived from Escherichia coli K-12 during the process of interaction with biotic and abiotic surfaces

A célula epitelial é o primeiro contato entre os micro-organismos e o hospedeiro. Essa interação pode levar a produção de diversas citocinas, quimiocinas, moléculas inflamatórias e também estimular a geração de espécies reativas de oxigênio (ERO). Neste trabalho avaliamos se a interação com as células HEp-2 poderia ser genotóxica para os mutantes derivados de Escherichia coli K-12 deficientes em algumas enzimas que fazem parte do sistema de reparo por excisão de base (BER). Além disto, avaliamos a expressão do sistema SOS, que é induzido pela presença de danos no genoma bacteriano. Os resultados obtidos mostraram a presença de filamentos, na interação com células HEp-2, principalmente, no mutante xthA (BW9091) e no triplo mutante xthA nfo nth (BW535). Quando a interação foi quantificada na ausência da D-manose, observamos um aumento das bactérias aderidas. Além disto, a quantidade e o tamanho dos filamentos também aumentaram, mostrando que as adesinas manose-sensíveis estavam envolvidas na filamentação bacteriana. Para comprovar se o aumento da filamentação observada neste ensaio foram uma consequência da indução do sistema SOS, desencadeada pela interação com as células HEp-2, quantificamos a expressão do SOS, na presença e na ausência da D-manose. De fato, observamos que a indução do SOS na ausência da D-manose foi maior, quando comparada, com o ensaio realizado na presença de D-manose. Além disto, observamos que a ausência de xthA foi importante para o aumento da filamentação observada na ausência de D-manose. Diante destes resultados, verificamos se a resposta de filamentação ocorreria quando as bactérias interagiam com uma superfície abiótica como o vidro. Observamos também inúmeros filamentos nos mutantes BER, BW9091 e BW535, quando comparados a cepa selvagem AB1157. Essa filamentação foi associada à indução do SOS, em resposta a interação das bactérias com o vidro...

The epithelial cell is the first contact between microorganisms and host. This interaction results in production of several cytokines, chemokines, and inflammatory molecules by epithelial cells and also stimulate the generation of reactive oxygen species (ROS). In the present study, we have evaluated whether the interaction to HEp-2 cells causes genotoxicity to mutants derived from Escherichia coli K-12 deficient in some enzymes that are part of the system of base excision repair (BER). Moreover, we measured the expression of SOS system, which is induced by the presence of damage to the bacterial genome. Our results showed mainly presence of filamentous bacterial growth in xthA mutant (BW9091) and triple xthA nfo nth mutant (BW535) when submitted to HEp-2 cells interaction assays. When experiments were performed in the absence of mannose, data showed enhanced interaction of viable bacteria to HEp-2 cells for all strains tested. Furthermore, the removal of D-mannose resulted in an increase in both number and size of bacterial filamentous forms, indicating the involvement of mannose-sensitive adhesins in the filamentation of these strains. In order to verify whether the increased filamentation growth in this assay was a consequence of SOS induction, triggered by interaction to HEp-2 cells, we measured expression of SOS in the presence and absence of D-mannose. Indeed, we observed higher expression of SOS response in the absence of mannose than in experiments performed in the presence of D-mannose. Moreover, we observed that the absence of xthA was important to filamentation increasing in absence of D-mannose. Based on these results, we verified if interaction to abiotic surfaces, like glass, could lead to filamentation of these strains. We also observed numerous filaments in BER mutants, BW9091 and BW535, when compared to wild-type strain AB1157. The filamentation observed was a consequence of SOS induction, triggered by attachment to the glass surface...

Chemical composition and antigenotoxic properties of Lippia alba essential oils

The present work evaluated the chemical composition and the DNA protective effect of the essential oils (EOs) from Lippia alba against bleomycin-induced genotoxicity. EO constituents were determined by Gas Chromatography/Mass Spectrometric (GC-MS) analysis. The major compounds encountered being citral (33 percent geranial and 25 percent neral), geraniol (7 percent) and trans-β-caryophyllene (7 percent) for L. alba specimen COL512077, and carvone (38 percent), limonene (33 percent) and bicyclosesquiphellandrene (8 percent) for the other, COL512078. The genotoxicity and antigenotoxicity of EO and the compounds citral, carvone and limonene, were assayed using the SOS Chromotest in Escherichia coli. The EOs were not genotoxic in the SOS chromotest, but one of the major compound (limonene) showed genotoxicity at doses between 97 and 1549 mM. Both EOs protected bacterial cells against bleomycin-induced genotoxicity. Antigenotoxicity in the two L. alba chemotypes was related to the major compounds, citral and carvone, respectively. The results were discussed in relation to the chemopreventive potential of L. alba EOs and its major compounds.

Citotoxicidad de extracto acuoso de corteza de Manguifera indica L (Vimang®) en Escherichia coli y linfocitos humanos / Cytotoxicity of the aqueous extract from the Manguifera indica L (Vimang®) in Escherichia coli and human lymphocytes

Vimang® es un producto de origen natural que se obtiene del árbol del mango (Manguifera indica L. familia Anacardiaceae). Este compuesto ha sido clasificado como antioxidante, inmunomodulador, etc. Por ello, resulta importante conocer su potencial citotóxico. OBJETIVOS: evaluar la citotoxicidad de un extracto acuoso del Vimang®. MÉTODOS: se emplearon los modelos procariótico (Escherichia coli, cepa PQ37) y eucariótico (eritrocitos humanos), se realizaron curvas de supervivencia celular con la cepa PQ37 (con activación metabólica y sin esta); así como se cuantificaron los niveles de la actividad fosfatasa alcalina (mediante la realización del SOS Chromotest). Posteriormente, se desarrolló el ensayo de inhibición de la actividad mitocondrial en eritrocitos. Las concentraciones de Vimang® estudiadas fueron: 50, 250, 500 y 1 000 mg de extracto liofilizado/mL. RESULTADOS: el ensayo procariótico indicó que, en ausencia de fracción S9, el Vimang® diminuye significativamente la viabilidad celular cuando se aplica a concentración igual o superior que 500 mg/mL. Sin embargo, la presencia de activación metabólica podría ocasionar una biotransformación de los componentes del Vimang® que conduce a la no citotoxicidad del producto en el rango de concentraciones analizado. El análisis de los niveles de fosfatasa alcalina cuantificados en presencia del Vimang®; sugirió que la citotoxicidad detectada en E. coli PQ37 no parece estar relacionada con la inhibición de la síntesis proteica. En el caso del ensayo eucariótico empleado y las concentraciones ensayadas, la supervivencia celular de los eritrocitos (en presencia de Vimang®)no disminuyó de forma significativa en relación con los controles correspondientes. CONCLUSIONES: el Vimang® es citotóxico para la cepa PQ37 de Escherichia coli...

Vimang® is a product of natural origin obtained from the mango tree (Manguifera indica L. Anacardiaceae family. This compound has been classified as antioxidant, immunomodulation agent, etc. Thus, it is important to know its cytotoxic potential. OBJECTIVES: to assess the cytotoxicity of a aqueous extract of Vimang®. METHODS: the prokaryotic (PQ37 strain-Escherichia coli and eukaryotic (human erutjrocytes) models and cellular survival curves with PQ37 strain (with and without metabolic activation) were made and the levels of alkaline phosphatase were quantified (by Chromotest SOS test). Later, a trial of mitochondria activity was developed in erythrocytes. The concentrations of study Vimang® were: 50, 250, 500 and 1 000 µg of lyophilized/mL extract. RESULTS: the prokaryotic trial indicated that, in absence of S9, Vimang® decrease significantly the cell viability when it is applied at a concentration similar o higher than 500 µg/mL. However, the presence of a metabolic activation could to cause a biotransformation of the Vimang's® components leading to the no-cytotoxicity of product within the study concentration rank. Analysis of alkaline phosphatase levels quantified in presence of Vimang® suggested that the cytotoxicity detected in PQ37 Escherichia coli apparently isn't related to protein synthesis inhibition. In the case of the eukaryotic trial used and the assayed concentrations, the cell survival of erythrocytes (in presence of Vimang® not decreased significantly in relation to the corresponding controls. CONCLUSIONS: Vimang® is cytotoxic for the PQ37 strain of E.coli when it is applied at a concentration similar or higher than 500 µg/mL. This effect is not observed in these cells neither when a metabolic activation is applied nor in the human erythrocytes for the conditions reported in present paper

The self-concept and personality of the children in the SOS children village / 中华行为医学与脑科学杂志

Objective To study the characteristics of self-concept and personality in the SOS children vil-lage's children. Methods Sixty-one children from SOS children village, sixty-one children with single parent and sixty-one children in intact family, matched with the SOS children in gender and age, were assessed by Piers-Harris children's self-concept Scale(PHCSS), Eysenck Personality Questionnaire for Children (EPQ) and general status questionnaire. Result In the PHCSS, the scores on behavior, body of color and attribute, blessedness and satisfac-tion and the total score of boys in the SOS group were lower than those in the intact family group's ((10.69± 2.74) vs (12.57±2.36),P=0.013;(6.51±2.63) vs (8.29±2.75), P=0.011;(6.54±1.93) vs (7.97± 1.60), P=0.004; (48.09±10.88) vs (55.86±10.11), P=0.007)). The E scale's score of the SOS group's girls was lower than that in the intact group (P=0.004). Children's self-concept status was related with their learning environment, family structure, parent' s learning expectation, daily communication, personality, number of good friends and academic performance (-0.566 < r < 0.395). Conclusions The self-concept status of girls in the SOS children village show lower level. The personality of boys in the SOS children village tend to be introver-sive and stable. Children's self-concept status was related with the factors of their personality, life environment,family structure,et al.

Site-Specific Mutagenesis in Escherichia coli by Bulky Exocyclic Amino-Substituted Guanine and Adenine Derivatives in Double-Stranded or Gapped Plasmids / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: 7-Bromomethylbenz[alpha]anthracene is a known mutagen and carcinogen. The mutagenic potency of its two major DNA adducts, i.e., N2-(benz[alpha]anthracen-7-ylmethyl)-2'-deoxyguanosine (b[alpha]a2G) and N6-(benz[alpha]anthracen-7-ylmethyl)-2'-deoxyadenosine (b[alpha]a6A), as well as the simpler benzylated analogs, N2-benzyl-2'-deoxyguanosine (bn2G) and N6-benzyl-2'-deoxyadenosine (bn6A), were determined in E. coli. MATERIALS AND METHODS: Double-stranded and gapped plasmid vectors were used to determine the mutagenicity of b[alpha]a2G, b[alpha]a6A, bn2G and bn6A in E. coli. The four, suitably protected, bulky exocyclic amino-substituted adducts were incorporated into 16-base oligodeoxyribonucleotides, in place of normal guanine or adenine residues, which form part of the ATG initiation codon for the lacZ' alpha-complementation gene. The site-specifically modified oligodeoxyribonucleotides were then incorporated into double-stranded plasmids, which contained uracil residues in the complementary strand in the vicinity of the initiation codon. The uracil residues lead to the creation of a gap in the complementary strand due to the actions of E. coli uracil-DNA glycosylase and AP endonuclease. Following the transfection of these plasmid vectors into E. coli strain GP102, a lacZ alpha complementing version of the parent strain AB1157, their propensity to induce mutation was investigated. RESULTS: The percentages of mutant colonies produced by the four modified nucleosides, in both the double-stranded and gapped plasmid vectors, were not significantly different from those produced by the unmodified plasmids. The mutagenicities of the b[alpha]a2G and b[alpha]a6A were extremely low, and a totally unexpected result, whereas, those of the bn2G and bn6A were undetectable. CONCLUSION: In this E. coli site-specific mutagenesis system, these bulky aralkylated adducts exhibited no significant mutagenicities, either with or without SOS induction.

Genetic Safety Study of Chlorpromazine / 신경정신의학

OBJECT: The aim of this study is to determine whether exposure to chlorpromazine causes mutagenicity and genetic disorders. METHOD: Ames (Salmonella typhimurium) test and Rec assay (Bacillus subtilis) were used as indicators for DNA damage. Furthermore, the levels of umu operon expression by measuring the beta-galactosidase activity were monitered with the SOS umu test using S. typhimurium 1535 containing plasmid pSK1002. And the host-mediated assay was used to investigate the muta-genicity of chlorpromazine after the activation with in vivo metabolic systems. RESULTS: From the results, chlorpromazine did not affect DNA of S. typhimurium and B. subtilis strains and showed no mutagenicity at the all concentrations tested. These phenomena was also similar to that after metabolic activation of chlorpromazine in in vivo system. CONCLUSION: These results suggested that chlorpromazine did not show the mutagenicity and genotoxicity by four different methods used in this study.

Genotoxic effect of alkaloids

Because of the increase use of alkaloids in general medical practice in recent years, it is of interest to determine genotoxic, mutagenic and recombinogenic response to different groups of alkaloids in prokaryotic and eucaryotic organisms. Reserpine, boldine and chelerythrine did not show genotoxicity response in the SOS-Chromotest whereas skimmianine showed genotixicity in the presence of a metabolic activation mixture. Voacristine isolated fromthe leaves of Ervatamia coronaria shows in vivo cytostatic and mutagenic effects in Saccharomyces cerevisiae hapioids cells. The Rauwolfia alkaloid (reserpine) was not able to induce reverse mutation and recombinational mitotic events (crossing-over and gene conversion) in yeast diploid strain XS2316.

Isolation and Identification of Antimutagenic Constituents in Hotbed Chives / 第二军医大学学报

Fresh hotbed chives solutions were extracted respectively by ether, acetic ether and n-butyl alcohol and protein constituents and non-protein constituents were obtained. Ether extractions (non-protein constituents) had the strongest antirriutagenic effects by the SOS chromotest Non-protein constituents of hotbed chives were analysed further by gas chromatography-mass spectrum and 30 chemical substances were isolated and identified. Their antimutagenic substances may be dimethyl disulfide, 4-methyl-2-pyridinethione, di-2-propenyl trisulfide, 3-(allylthio)-propionic acid.

Antimutagenic Mechanisms of Hotbed Chives, Fragrant-Flowered Garlic and Garlic Leaves / 第二军医大学学报

In the present paper, antimutagenic mechanisms of hotbed chives, fragrant-flowered garlic and garlic leaves were investigated by the SOS Chromotest The results showed that these vegetables could inhibit the SOS respones induced by temperature (42℃) in E coli GW1060 and GW11M (rec 441 (tif)), but they could not act on SOS network gene expression in E. coli GW2707 (lexA::Tn5), so one of their antimutagenic mechanisms is inhibitory effect on cleavage of lexA by RecA protease. Desmutagenic test results indicate that some aqueous extractions of the three vegatables can inactivate mutagens outside cells.

Antimutagenic Effects of 17 Compounds / 第二军医大学学报

The inhibitory and antimutagenic effects of 17 compounds, cysteine (1), cinnamic acid (2), rutin (3), tannic acid (4), germanium dioxide (5), fluro uracil (6), sodium copper chlorophylline (7), B-sitosterol (8), vitamin C (9), coumarin (10), vitamin E (11), L-glutathione (oxidized form) (12), L-glutathione (reduced form) (13), sodium selenile (14), organic germanium (15), L-methioine (16) and proline (17) on the SOS response induced by N-methyl-N'-nitro-N-nitrosoguanidine, niethly muthanesulfonate, benzo (a)pyrine and UV were studied by using SOS chromotest. The results showed that compounds 1~15 revealed inhibitory effects, and compounds 2~8 and 10-11 revealed antimutagenic effects. It was demonstrated that cinnamic acid is the best antimutagen among 17 compounds. Cinnamic acid has not only inhibitory effect but also antimutagenic activity towards a wide variety of mutagens/carcinogens. The modes, specificity and end point of action of antimutagens are discussed.