42 research outputs found

    Analysis for genotyping Duffy blood group in inhabitants of Sudan, the Fourth Cataract of the Nile

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    <p>Abstract</p> <p>Background</p> <p>Genetic polymophisms of the Duffy antigen receptor for the chemokines (DARC) gene successfully protected against blood stage infection by <it>Plasmodium vivax </it>infection. The Fy (a-, b-) phenotype is predominant among African populations, particularly those originating from West Africa, and it is rare among non-African populations. The aim of this study was to analyse the frequency of four Duffy blood groups based on SNPs (T-33C, G125A, G298A and C5411T) in two local tribes of Sudanese Arabs, the <it>Shagia </it>and <it>Manasir</it>, which are both from the region of the Fourth Nile cataract in Sudan.</p> <p>Methods</p> <p>An analysis of polymorphisms was performed on 217 individuals (126 representatives of the <it>Shagia </it>tribe and 91 of the <it>Manasir)</it>. Real-time PCR and TaqMan Genotyping Assays were used to study the prevalence of alleles and genotypes.</p> <p>Results</p> <p>The analysis of allelic and genotype frequency in the T-33C polymorphisms demonstrated a significant dominance of the <it>C </it>allele and <it>CC </it>genotype (OR = 0.53 [0.32-0.88]; p = 0.02) in both tribes. The G125A polymorphism is associated with phenotype Fy(a-, b-) and was identified in 83% of <it>Shagia </it>and 77% of <it>Manasir</it>. With regard to G298A polymorphisms, the genotype frequencies were different between the tribes (p = 0,002) and no single <it>AA </it>homozygote was found. Based on four SNPs examined, 20 combinations of genotypes for the <it>Shagia </it>and <it>Manasir </it>tribes were determined. The genotype <it>CC/AA/GG/CT </it>occurred most often in <it>Shagia </it>tribe (45.9%) but was rare in the <it>Manasir </it>tribe (6.6%) (p < 0.001 <it>Shagia </it>versus <it>Manasir</it>). The <it>FY*A<sup>ES </sup></it>allele was identified in both analysed tribes. The presence of individuals with the <it>FY*A/FY*A </it>genotype was demonstrated only in the <it>Shagia </it>tribe.</p> <p>Conclusion</p> <p>This is probably the first report showing genotypically Duffy-negative people who carry both <it>FY*B<sup>ES </sup></it>and <it>FY*A<sup>ES</sup></it>. The identification of the <it>FY*A<sup>ES </sup></it>allele in both tribes may be due to admixture of the non-African genetic background. Taken as a whole, allele and genotype frequencies between the <it>Shagia </it>and the <it>Manasir </it>were statistically different. However, the presence of individuals with the <it>FY*A/FY*A </it>genotype was demonstrated only in the <it>Shagia </it>tribe.</p

    Duffy blood group gene polymorphisms among malaria vivax patients in four areas of the Brazilian Amazon region

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    <p>Abstract</p> <p>Background</p> <p>Duffy blood group polymorphisms are important in areas where <it>Plasmodium vivax </it>predominates, because this molecule acts as a receptor for this protozoan. In the present study, Duffy blood group genotyping in <it>P. vivax </it>malaria patients from four different Brazilian endemic areas is reported, exploring significant associations between blood group variants and susceptibility or resistance to malaria.</p> <p>Methods</p> <p>The <it>P. vivax </it>identification was determined by non-genotypic and genotypic screening tests. The Duffy blood group was genotyped by PCR/RFLP in 330 blood donors and 312 malaria patients from four Brazilian Amazon areas. In order to assess the variables significance and to obtain independence among the proportions, the Fisher's exact test was used.</p> <p>Results</p> <p>The data show a high frequency of the <it>FYA/FYB </it>genotype, followed by <it>FYB/FYB, FYA/FYA</it>, <it>FYA/FYB-33 </it>and <it>FYB/FYB-33</it>. Low frequencies were detected for the <it>FYA/FY</it><sup><it>X</it></sup>, <it>FYB/FY</it><sup><it>X</it></sup>, <it>FYX/FY</it><sup><it>X </it></sup>and <it>FYB-33/FYB-33 </it>genotypes. Negative Duffy genotype (<it>FYB-33/FYB-33</it>) was found in both groups: individuals infected and non-infected (blood donors). No individual carried the <it>FY</it><sup><it>X</it></sup><it>/FYB-33 </it>genotype. Some of the Duffy genotypes frequencies showed significant differences between donors and malaria patients.</p> <p>Conclusion</p> <p>The obtained data suggest that individuals with the <it>FYA/FYB </it>genotype have higher susceptibility to malaria. The presence of the <it>FYB-33 </it>allele may be a selective advantage in the population, reducing the rate of infection by <it>P. vivax </it>in this region. Additional efforts may contribute to better elucidate the physiopathologic differences in this parasite/host relationship in regions endemic for <it>P. vivax </it>malaria, in particular the Brazilian Amazon region.</p

    Vivax malaria in Mauritania includes infection of a Duffy-negative individual

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    <p>Abstract</p> <p>Background</p> <p>Duffy blood group polymorphisms are important in areas where <it>Plasmodium vivax </it>is present because this surface antigen is thought to act as a key receptor for this parasite. In the present study, Duffy blood group genotyping was performed in febrile uninfected and <it>P. vivax</it>-infected patients living in the city of Nouakchott, Mauritania.</p> <p>Methods</p> <p><it>Plasmodium vivax </it>was identified by real-time PCR. The Duffy blood group genotypes were determined by standard PCR followed by sequencing of the promoter region and exon 2 of the Duffy gene in 277 febrile individuals. Fisher's exact test was performed in order to assess the significance of variables.</p> <p>Results</p> <p>In the Moorish population, a high frequency of the <it>FYB<sup>ES</sup>/FYB<sup>ES </sup></it>genotype was observed in uninfected individuals (27.8%), whereas no <it>P. vivax</it>-infected patient had this genotype. This was followed by a high level of <it>FYA/FYB</it>, <it>FYB/FYB</it>, <it>FYB/FYB<sup>ES </sup></it>and <it>FYA/FYB<sup>ES </sup></it>genotype frequencies, both in the <it>P. vivax</it>-infected and uninfected patients. In other ethnic groups (Poular, Soninke, Wolof), only the <it>FYB<sup>ES</sup>/FYB<sup>ES </sup></it>genotype was found in uninfected patients, whereas the <it>FYA/FYB<sup>ES </sup></it>genotype was observed in two <it>P. vivax</it>-infected patients. In addition, one patient belonging to the Wolof ethnic group presented the <it>FYB<sup>ES</sup>/FYB<sup>ES </sup></it>genotype and was infected by <it>P. vivax</it>.</p> <p>Conclusions</p> <p>This study presents the Duffy blood group polymorphisms in Nouakchott City and demonstrates that in Mauritania, <it>P. vivax </it>is able to infect Duffy-negative patients. Further studies are necessary to identify the process that enables this Duffy-independent <it>P. vivax </it>invasion of human red blood cells.</p

    Artísta Plástica invitada Laura Herrera

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    Para la Revista Alternativa Multicultural La Moviola es muy placentero contar en su edición 102 con la fotógrafa colombiana Laura D. Herrera , quien ha desarrollado una obra fotográfica, donde el equilibrio entre lo arquitectónico y lo poético hacen tránsito. La forma en que Laura ha desarrollado su talento fotográfico, ha sido construida desde la música, la lectura, la pintura, las artes plásticas y la pedagogía . De esta forma Laura D. Herrera, se suma a la nueva generación de fotógrafas colombianas. Este es el texto que ella misma elaboró para su presentación a los lectores de la Revista Alternativa Multicultural La Moviola

    The Impact of China’s 'Fuzzy Logic' Legal System on Chinese AI Development

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    University of Technology Sydney. Faculty of Law.The broad aim of this research is to examine the extent to which Chinese laws and policies on cyber and network security act as a constraint on the emergence of Chinese entrepreneurialism and innovation. This thesis begins by exploring the contradictions and tensions between China’s innovation policies (Internet Plus) and its regulatory restrictions on networks and data (Network Sovereignty), focusing specifically on whether data localisation policies in China’s Cyber Security Law will hinder Chinese firms’ innovation and global reach. The Cyber Security Law (2017) is the doctrinal centrepiece of China’s Network Sovereignty conceptions. More specifically, this thesis focuses on how data localisation laws (as part of Network Sovereignty) affect innovation in artificial intelligence (‘’), a key component of Internet Plus. This is achieved by explaining how these developments (globalised research and development networks, and the increasing use of open-source platforms by leading Chinese AI firms during 2017–19) exacerbated the apparent contradiction between Network Sovereignty and Chinese innovation. It is shown that the drafting of the Cyber Security Law did not anticipate the changing nature of globalised AI innovation. However, the main argument of this thesis is that the deliberate deployment of what the thesis refers to as ‘fuzzy logic’ in drafting the Cyber Security Law allowed regulators subsequently to interpret key terms regarding data in that Law in a fluid and flexible fashion to benefit Chinese innovation. There are still numerous uncertainties surrounding the interplay between Network Sovereignty and innovation in China, which cannot be resolved at this stage. How China’s Cyber Security Law is eventually enforced, in a world of global open innovation in AI, will have a major bearing on Chinese progress as a potential world leader in AI technologies. The documentation in this thesis of the evolution of the Cyber Security Law and associated regulations during the period 2015–19 advances the current law and technology literature regarding the nature of vague legislative decisions in Chinese technology lawmaking. Specifically, the analysis in this thesis of the implementation of the data localisation provisions under the Cyber Security Law using the concepts of fuzzy logic and policy petri dishes adds to the literature on regulatory practice in China. Importantly, this thesis also explains the problematic relationship between open-source platforms and data localisation

    Duffy Antigen/Receptor for Chemokines (DARC): Genotypes in Ashkenazi and Non-Ashkenazi Jews in Israel

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    Duffy genotypes were studied in Ashkenazi and non-Ashkenazi groups in Israel. The prevalence of the genotypes for the known polymorphic FY*A, FY*B, and FY*BGATA- alleles was similar in the two groups. The recently described FY*BG298A and FY*BC265T alleles were also found to be polymorphic. FY*BG298A was significantly more prevalent in the non-Ashkenazi group than in the Ashkenazi group (in 20% and 10% of FY*B, respectively). FY*BC265T, which markedly diminishes the expression of Fyb antigen, was found in 3.5% of FY*B alleles, but only together with FY*BG298A, consistent with previous suggestions that FY*BC265T occurred in the FY*BG298A allele. No difference in Duffy genotype distribution was found between schizophrenic and control groups. Duffy antigens are receptors for chemokines and bind Plasmodium vivax. Study of Duffy genotypes in additional populations might help in elucidating the possible functional significance of Duffy allele polymorphism
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