Cytotoxic and genotoxic effects of tambjamine D, an alkaloid isolated from the nudibranch Tambja eliora, on Chinese hamster lung fibroblasts

Marine organisms have been shown to be potential sources of bioactive compounds with pharmaceutical applications. Previous chemical investigation of the nudibranch Tambja eliora led to the isolation of the alkaloid tambjamine D. Tambjamines have been isolated from marine sources and belong to the family of 4-methoxypyrrolic-derived natural products, which display promising immunosuppressive and cytotoxic properties. Their ability to intercalate DNA and their pro-oxidant activity may be related to some of the biological effects of the 4-methoxypyrrolic alkaloids. The aim of the present investigation was to determine the cytotoxic, pro-oxidant and genotoxic properties of tambjamine D in V79 Chinese hamster lung fibroblast cells. Tambjamine D displayed a potent cytotoxic effect in V79 cells (IC50 1.2 mu g/mL) evaluated by the MTT assay. Based on the MTT result, V79 cells were treated with different concentrations of tambjamine D (0.6. 1.2. 2.4 and 4.8 mu g/mL). After 24 h, tambjamine D reduced the number of viable cells in a concentration-dependent way at all concentrations tested. assessed by the trypan blue dye exclusion test. The hemolytic assay showed that the cytotoxic activity of tambjamine D was not related to membrane disruption (EC50 > 100 mu g/mL). Tambjamine D increased the number of apoptotic cells in a concentration-dependent manner at all concentrations tested according to acridine orange/ethidium bromide staining, showing that the alkaloid cytotoxic effect was related to the induction of apoptosis. MTT reduction was stimulated by tambjamine D, which may indicate the generation of reactive oxygen species. Accordingly, treatment of cells with tambjamine D increased nitrite/nitrate at all concentrations and TBARS production starting at the concentration corresponding to the IC50. Tambjamine D, also, induced DNA strand breaks and increased the micronucleus cell frequency as evaluated by comet and micronucleus tests, respectively, at all concentrations evaluated. showing a genotoxic risk induced by tambjamine D. (C) 2008 Elsevier Ireland Ltd. All rights reserved.

Chinese Basic Pension Substitution Rate: A Monte Carlo Demonstration of the Individual Account Model

At the end of 2005, the State Council of China passed ”The Decision on adjusting the Individual Account of Basic Pension System”, which adjusted the individual account in the 1997 basic pension system. In this essay, we will analyze the adjustment above, and use Life Annuity Actuarial Theory to establish the basic pension substitution rate model. Monte Carlo simulation is also used to prove the rationality of the model. Some suggestions are put forward associated with the substitution rate according to the current policy.

A Linguistic Analysis of the Written Production of Second Language Learners : The Variation of Article Usage by Adult Chinese Learners of English

This study aims to test Robertson’s lexical transfer principle, which posits that Chinese learners use demonstratives (particularly this) and the numeral one as markers of definiteness and indefiniteness. This is tested by analysing Chinese learners’ written production collected from the Spoken and Written English Corpus of Chinese Learners 2.0 (SWECCL 2.0). The purpose is to understand the variation of article usage by adult Chinese learners of English. More specifically, the study examines to what extent articles, possessive and demonstrative pronouns are used in Chinese learners’ English and how definite and indefinite articles are used by the Chinese learners. Findings suggest that Robertson’s lexical transfer principle was corroborated by the present study. In addition, Chinese learners prefer to use demonstrative determiners, the possessive determiner our, and the numeral one to perform the function of marking definiteness and indefiniteness. In particular, the learners try to use the demonstrative determiners that and this in the anaphoric function instead of the definite article, and the demonstrative determiner those is frequently used in the cataphoric function. What is more, the learners use the numeral one as a marker of indefiniteness, and it is also used as a marker of definiteness in the anaphoric function. Further, the possessive determiner our is used as a marker of definiteness in larger situation uses referring to something unique. To this end, the study is able to show that the definite article is used to perform the function of marking indefiniteness, and in some particular contexts the definite article functions as a Chinese specifier in Chinese learners’ English. Also, the indefinite article is frequently used in quantifier phrases but is rarely used in other functions. There are three main reasons that may explain why Chinese learners use determiners variously. Firstly, the choice of determiners by Chinese learners is influenced by linguistic contexts. Secondly, because of learning strategies, Chinese learners try to ignore the anaphoric function and cataphoric function that they are not yet ready to process in article usage. Thirdly, interlanguage grammar influences the optionality in the use of articles. 

Enhancing Intercultural Communication in Teaching Chinese as a Foreign Language : An Action Research Study

Enhancing Intercultural Communication in Teaching Chinese as a Foreign Language – An Action Research Study Over the past few decades, the rapid development of information communication technology, internationalization and globalization worldwide have required a shift in the focus of Chinese as a foreign language (CFL) towards competence in intercultural communication in which the role of culture in the acquisition of CFL and in the pragmatic use of the language is emphasized and promoted. However, most of the current research in this academic area remains only on a theoretical level. Practical examples, particularly with regard to distance learning/teaching of the Chinese language, are very limited. This motivated the implementation of an action research study which aimed at exploring the possibilities and limitations of integrating Chinese culture and applying intercultural communication theory into a contemporary distance CFL course for beginners. By observing and comparing the performance of subjects in the control and experimental groups, this action research study focuses on exploring three basic areas. Firstly, it discloses the cultural elements which underlie effective daily communication. Secondly, it investigates how students acquire cultural knowledge and develop their ability to competently communicate in the target course. And thirdly, it evaluates how the modified course syllabus could enhance students’ intercultural communicative competence. The findings of the research aim to serve as both a resource and reference for educators and researchers who are interested in carrying out reforms and research in this academic domain.

Obstacles for chinese and brazilian companies in the bilateral trade between China and Brazil

Brasil e a República Popular da China iniciaram a sua relação diplomática em 1974, na época, o comércio entre Brasil e China foi de apenas 17,42 milhões de dólares, 5 anos depois, em 1979, a escala deste comércio bilateral aumentou 12 pastas. Hoje em dia, o comércio bilateral entre a China e o Brasil já contava mais de 57,000 milhões de dólares USD. China tornou-se já o primeiro parceiro comercial do Brasil, e do Brasil em troca torna-se o primeiro parceiro comercial na América Latina. Esta dissertação teve como objetivo compreender os obstáculos para as PME brasileiras e chinesas no comércio entre os dois países e dar recomendações às autoridades públicas e empresas privadas sobre como superá-los. Com uma análise qualitativa, baseada em entrevistas com as empresas chinesas e brasileiras para identificar quais são os obstáculos mais graves para as empresas brasileiras e chinesas para beneficiar mais o comércio bilateral. O estudo feito pela OCDE-APEC em barreiras de internacionalização das PME é usado como um quadro para melhor identificar quais são os obstáculos mais graves no caso das PME brasileiras e chinesas.

How national culture on consumers' decision-making styles: a comparative study among Americans, Brazilians, Chinese, and japanese in the purchase of cell phones.

The influence of the national culture on consumer decision-making styles is investigated using a sample of Americans, Brazilians, Chinese, and Japanese consumers who have purchased a cell phone in the past three years. To make the research possible, a survey was used as a method of data collection. It relates Hofstede’s cultural classification typology with Sproles and Kendall’s consumer style inventory (CSI). The multivariate analysis of variance (MANOVA) results indicate six decision-making styles together with other consumer behavioral characteristics that can be used to distinguish and profile consumers who purchase cell phones. Empirical findings reveal that among Americans, Brazilians, and Japanese; Americans are the most quality conscious, brand conscious, innovative, and hedonistic shoppers; Brazilians are the most loyal, and Japanese, the most confused by overchoice consumers. Conceptual contributions and managerial implications are discussed.

Exploring different social media users from the millennials’ generation: a cross-cultural behavioral analysis of brazilian users of Facebook and chinese users of RenRen

With the increasing importance of digital communication and its distinct characteristics, marketing tools and strategies adopted by companies have changed dramatically. Among the many digital marketing tools and new media channels available for marketers, the phenomenon known as social media is one of the most complex and enigmatic. It has a range that still is quite unexplored and deeply transforms the present view on the promotion mix (Mangold & Faulds, 2009). Conversations among users on social media directly affect their perceptions on products, services and brands. But more than that, a wide range of other subjects can also become topics of conversations on social media. Hit songs, sporting events, celebrity news and even natural disasters and politics are topics that often become viral on the web. Thus, companies must grasp that, and in order to become more interesting and relevant, they must take part in these conversations inserting their brands in these online dynamic dialogues. This paper focuses on how these social interactions are manifested in the web in to two distinct cultures, Brazil and China. By understanding the similarities and differences of these cultures, this study helps firms to better adjust its marketing efforts across regions, targeting and positioning themselves, not only geographically and culturally, but also across different web platforms (Facebook and RenRen). By examining how companies should focus their efforts according to each segment in social media, firms can also maximize its results in communication and mitigate risks. The findings suggest that differences in cultural dimensions in these two countries directly affect their virtual social networking behavior in many dimensions (Identity, Presence, Relationships, Reputation, Groups, Conversations and Sharing). Accordingly, marketing efforts must be tailored to each comportment and expectations.

Is what you say what you do? Analyzing and comparing the effect of buyer-supplier relationship in the Brazilian and Chinese supplier selection criteria

Choosing properly and efficiently a supplier has been challenging practitioners and academics since 1960’s. Since then, countless studies had been performed and relevant changes in the business scenario were considered such as global sourcing, quality-orientation, just-in-time practices. It is almost consensus that quality should be the selection driver, however, some polemical findings questioned this general agreement. Therefore, one of the objectives of the study was to identify the supplier selection criteria and bring this discussion back again. Moreover, Dickson (1966) suggested existing business relationship as selection criterion, then it was reviewed the importance of business relationship for the company and noted a set of potential negative effects that could rise from it. By considering these side effects of relationship, this research aimed to investigate how the relationship could influence the supplier selection and how its harmful effects could affect the selection process. The impact of this phenomenon was investigated cross-nationally. The research strategy adopted was a controlled experiment via vignette combined with discrete choice analysis. The data collections were performed in China and Brazil. By examining the results, it could be drawn five major findings. First, when purchasers were asked to declare their supplier selection priorities, quality was stated as the most important independently of country and relationship. This result was consistent with diverse studies since 60’s. However, when purchasers were exposed to a multi-criteria trade-off situation, their actual selection priorities deviate from what they had declared. In the actual decision-making without influence of buyer-supplier relationship, Brazilian purchasers focused on price and Chinese buyers prioritized delivery then price. This observation reinforced some controversial prior studies of Verma & Pullman (1998) and Hirakubo & Kublin (1998). Second, through the introduction of the buyer-supplier relationship (operationalized via relational capital) in the supplier selection process, this research extended the existing studies and found that Brazilian buyers still focused on price. The relationship became just another criterion for supplier selection such as quality and delivery. However, from the Chinese sample, the results suggested that quality was totally discarded and the decision was majorly made through price and relationship. The third finding suggested that relational capital could legitimate the quality and sustainability of the supplier and replaces these selection criteria and made the decisional task less complex. Additionally, with the relational capital, the decision-makings were associated to few biases such as availability cognition, commitment, confirmatory and perceived biases. By analyzing the purchasers’ behavior, relational capital inducted buyers of both countries to relax in their purchasing requirements (quality, delivery and sustainability) leading to potential negative effects. In the Brazilian sample, the phenomenon of willing to pay a higher price for a lower quality offer demonstrated to be a potential counterproductive and suboptimal decision. Finally, the last finding was associated to the cultural effect on the buyers’ decisions. From the outcome, it is possible to observe that if a purchaser’s cultural background is more relation-oriented, the more he will tend to use relational capital as a decision heuristic, thus, the purchaser will be more susceptible to the potential relationship’s side effects

Main obstacles in the business environment affecting firm growth: a comparative analysis between Chinese and Brazilian SMEs

Usando dados do Banco Mundial, esta dissertação analisa as semelhanças e diferenças entre os obstáculos enfrentados pelas micro, pequenas e médias empresas (MSME) no Brasil e na China. Realizamos tanto uma análise comparativa entre os dos países como uma análise de clusters para confrontar os dados subjetivos e objetivos recolhidos, de modo a identificar o desempenho das empresas, levando em consideração as características dos países e o ambiente de negócios.

Genotoxicity and cytotoxicity of glass ionomer cements on Chinese hamster ovary (CHO) cells

Glass ionomer cements are widely used in dentistry as restorative materials and adhesives for composite restorations. However, the results of genotoxicity studies using these materials are inconclusive in literature. The goal of this study was to examine the genotoxic and cytotoxic potential of three different glass ionomer cements available commercially (Ketac Cem, Ketac Molar and Vitrebond) by the single cell gel (comet) assay and trypan blue exclusion test, respectively. For this, such materials were exposed to Chinese hamster ovary (CHO) cells in vitro for 1 h at 37 degrees C. Data were assessed by Kruskall-Wallis nonparametric test. The results showed that the powder from Ketac Molar displayed genotoxicity only in the maximum concentration evaluated (100 mu g/mL). In the same way, the liquid from Vitrebond at 0.1% dilution caused an increase of DNA injury. Significant differences (P < 0.05) in cytotoxicity provoked by all powders tested of glass ionomer cements were observed for exposure at 1000 mu g/mL concentration. With respect to liquids of glass ionomer cements evaluated, the major toxic effect on cell viability was produced at 10%, beginning at the dilution of 0.5% for Vitrebond. Taken together, we conclude that some components of glass ionomer cements show both genotoxic and cytotoxic effects.

Genotoxicity of antimicrobial endodontic compounds by single cell gel (comet) assay in Chinese hamster ovary (CHO) cells

Objective. In the current study, the potential DNA damage associated with exposure to a number of antimicrobial endodontic compounds was assessed by the single cell gel (comet) assay in vitro.Study design. Chinese hamster ovary (CHO) cells were exposed to formocresol, paramonochlorophenol, calcium hydroxide, or chlorhexidine at final concentration ranging from 0.01% to 1%.Results. Formocresol, paramonochlorophenol, and calcium hydroxide, as well as chlorhexidine in all concentrations tested did not contribute to the DNA damage.Conclusion. These findings are clinically relevant since they represent an important contribution to the correct evaluation of the potential health risk associated with exposure to dental agents.

Type-4 esophageal hiatal hernia in a Chinese Shar-pei dog

Thoracic radiography of a 3-month-old, female Chinese Shar-pei revealed an esophageal hiatal hernia with stomach, liver, and small intestine displaced into the thorax. Three days after the surgical correction, the dog developed ileal intussusception and was reoperated. Recovery was uncomplicated and the dog was asymptomatic 16 months after surgery.