Recombinant Dense Granular Protein (GRA5) for Detection of Human Toxoplasmosis by Western Blot

Toxoplasma gondii infects all warm-blooded animals, including humans, causing serious public health problems and great economic loss for the food industry. Commonly used serological tests require costly and hazardous preparation of whole Toxoplasma lysate antigens from tachyzoites. Here, we have evaluated an alternative method for antigen production, which involved a prokaryotic expression system. Specifically, we expressed T. gondii dense granular protein-5 (GRA5) in Escherichia coli and isolated it by affinity purification. The serodiagnostic potential of the purified recombinant GRA5 (rGRA5) was tested through Western blot analysis against 212 human patient serum samples. We found that rGRA5 protein was 100% specific for analysis of toxoplasmosis-negative human sera. Also, rGRA5 was able to detect acute and chronic T. gondii infections (sensitivities of 46.8% and 61.2%, resp.)

Controle de arritmias atriais com período refratário atrial controlado por sensor e mudança automática de modo em pacientes portadores de marcapasso dupla-câmara com sensor de ventilaçao por minuto

Apesar de um longo período refratário atrial pós evento ventricular (PVARP) poder prevenir a ocorrência de taquicardias mediadas pelo marca passo e também o sincronismo inapropriado com arritmias atriais na estimulaçao dupla-câmara (DDD) a limitaçao da freqüência máxima será necessariamente comprometida. Testamos a possibilidade de utilizar um marca passo dupla-câmara com sensor de ventilaçao por minuto (DDDR) e com capacidade de encurtar o PVARP durante o exercício em 13 pacientes com bradicardia (PVARP em repouso = 463 ± 29 ms) a fim de prevenir a limitaçao prematura da freqüência máxima. O teste de esforço em esteira nos modos DDD e DDDR com este PVARP resultou em freqüências máximas de 98 bpm ± 8 bpm e 142 bpm ± 3 bpm respectivamente (P < 0,DDD1). Estes resultados foram obtidos graças à incompetência cronotrópica e à limitaçao da freqüência máxima no modo DDD, ambas contornadas pelo uso do sensor. Com a finalidade de simular arritmias atriais, foi aplicada estimulaçao na parede torácica por 30 segundos, a uma freqüência de 250 bpm e com uma sensibilidade atrial uni polar média de 0,82 mV. No modo DDD, ocorreu uma resposta ventricular irregular (as freqüências com um PVARP de 280 ms e 463 ms ± 29 ms foram respectivamente 92 bpm ± 5 bpm e 66 bpm ± 3 bpm (P < 0,DDD1). No modo DDDR, com um PVARP de 463 ms ± 29 ms, ocorreu uma estimulaçao ventricular regular a 53 bpm ± 2 bpm, devida à mudança de mDDD para VVIR, na presença de eventos repetitivos captados dentro do PVARP. Um paciente desenvolveu fibrilaçao atrial espontânea durante o seguimento, que foi corretamente identificada pelo algoritmo do marcapasso, resultando na mudança de modo de DDDR para WIR e na preservaçao da resposta em freqüência. Em conclusao, o PVARP controlado pelo sensor permite a utilizaçao de um PVARP mais longo durante o repouso, sem comprometer a freqüência máxima durante o exercício. Adicionalmente, ao oferecer em proteçao contra conduçao retrógrada, o PVARP longo e a mudança automática de mDDD também limitam a freqüência durante as arritmias atriais, permitindo uma resposta ventricular de acordo com a demanda fisiológica

Perspectives of vector management in the control and elimination of vector-borne zoonoses

The complex transmission profiles of vector-borne zoonoses (VZB) and vector-borne infections with animal reservoirs (VBIAR) complicate efforts to break the transmission circuit of these infections. To control and eliminate VZB and VBIAR, insecticide application may not be conducted easily in all circumstances, particularly for infections with sylvatic transmission cycle. As a result, alternative approaches have been considered in the vector management against these infections. In this review, we highlighted differences among the environmental, chemical, and biological control approaches in vector management, from the perspectives of VZB and VBIAR. Concerns and knowledge gaps pertaining to the available control approaches were discussed to better understand the prospects of integrating these vector control approaches to synergistically break the transmission of VZB and VBIAR in humans, in line with the integrated vector management (IVM) developed by the World Health Organization (WHO) since 2004

Emerging patterns of genetic diversity in the critically endangered Malayan tiger (Panthera tigris jacksoni)

Southeast Asia experiences some of the highest deforestation in the world. Loss of tropical forest typically leads to widespread habitat fragmentation, with detrimental effects on dispersal ability and gene flow—particularly for large carnivores. We conducted mtDNA and microsatellite analysis to assess—for the first time—contemporary patterns of genetic diversity in the Malayan tiger. We collected 295 suspected carnivore samples in Peninsular Malaysia, from which we identified 26 as originating from tiger using 16 polymorphic microsatellite loci, comprising 22 individual tigers. Despite limitations of the study, our findings suggest tiger subpopulations in the north of the peninsula maintain some genetic connectivity and migration between two putative geographic subpopulations in the Main Range and Greater Taman Negara, with negligible population segregation due to dispersal barriers such as road infrastructure. We identified consistently lower levels of genetic diversity in tigers in the Greater Taman Negara region compared to tigers in the Main Range and small but emerging differences in nuclear and mitochondrial genetic diversity. Our mtDNA haplotype and nuclear DNA analyses suggest the levels of genetic diversity in Malayan tigers may be amongst some of the lowest of the surviving tiger subspecies, though the study is limited both in scale and genomic loci. Our findings are consistent with an expected lag between the rapid decline of tigers in Peninsular Malaysia by over 95% in the last 70 years and observed differences in their levels of genetic diversity

TSPYL2 Is Important for G1 Checkpoint Maintenance upon DNA Damage

Nucleosome assembly proteins play important roles in chromatin remodeling, which determines gene expression, cell proliferation and terminal differentiation. Testis specific protein, Y-encoded-like 2 (TSPYL2) is a nucleosome assembly protein expressed in neuronal precursors and mature neurons. Previous studies have shown that TSPYL2 binds cyclin B and inhibits cell proliferation in cultured cells suggesting a role in cell cycle regulation. To investigate the physiological significance of TSPYL2 in the control of cell cycle, we generated mice with targeted disruption of Tspyl2. These mutant mice appear grossly normal, have normal life span and do not exhibit increased tumor incidence. To define the role of TSPYL2 in DNA repair, checkpoint arrest and apoptosis, primary embryonic fibroblasts and thymocytes from Tspyl2 deficient mice were isolated and examined under unperturbed and stressed conditions. We show that mutant fibroblasts are impaired in G1 arrest under the situation of DNA damage induced by gamma irradiation. This is mainly attributed to the defective activation of p21 transcription despite proper p53 protein accumulation, suggesting that TSPYL2 is additionally required for p21 induction. TSPYL2 serves a biological role in maintaining the G1 checkpoint under stress condition

Evaluation of Toxoplasma gondii-recombinant dense granular protein (GRA2) for serodiagnosis by western blot

Abstract Toxoplasma gondii infects all warm-blooded animals including humans, causing serious public health problems and great economic loss in the food industry. Commonly used serological tests involve preparation of whole Toxoplasma lysate antigens from tachyzoites which are costly and hazardous. An alternative method for better antigen production involving the prokaryotic expression system was therefore used in this study. Recombinant dense granular protein, GRA2, was successfully cloned, expressed, and purified in Escherichia coli, BL21 (DE3) pLysS. The potential of this purified antigen for diagnosis of human infections was evaluated through western blot analysis against 100 human serum samples. Results showed that the rGRA2 protein has 100 and 61.5 % sensitivity towards acute and chronic infection, respectively, in T. gondii-infected humans, indicating that this protein is useful in differentiating present and past infections. Therefore, it is suitable to be used as a sensitive and specific molecular marker for the serodiagnosis of Toxoplasma infection in both humans and animals

Recombinant Dense Granular Protein (GRA5) for Detection of Human Toxoplasmosis by Western Blot

Toxoplasma gondii infects all warm-blooded animals, including humans, causing serious public health problems and great economic loss for the food industry. Commonly used serological tests require costly and hazardous preparation of whole Toxoplasma lysate antigens from tachyzoites. Here, we have evaluated an alternative method for antigen production, which involved a prokaryotic expression system. Specifically, we expressed T. gondii dense granular protein-5 (GRA5) in Escherichia coli and isolated it by affinity purification. The serodiagnostic potential of the purified recombinant GRA5 (rGRA5) was tested through Western blot analysis against 212 human patient serum samples. We found that rGRA5 protein was 100% specific for analysis of toxoplasmosis-negative human sera. Also, rGRA5 was able to detect acute and chronic T. gondii infections (sensitivities of 46.8% and 61.2%, resp.)

An Evaluation of Corporate Governance Characteristics and Corporate Performance between Government-Linked Companies (GLCs) in Malaysia and Singapore: A Panel Data Analysis

This research seeks to investigate whether corporate governance contributes to the Government-link public listed companies’ performance in Malaysia and Singapore. A sample consisting of 20 Malaysian Government-linked public listed companies and 20 Singaporean Government-linked public listed companies were selected. The research timeframe covers from 2012 to 2017. Findings revealed that except for board meetings and independent directors, 4 other independent variables were statistically significant in affecting the Malaysian and Singaporean government-link public listed companies’ performance. Directors’ ownership had a significant negative impact on ROA and ROE in Malaysia but had no impact in Singapore. Board meetings and independent directors had no impact towards firm performance in both countries. Board size had positive and significant impact on ROE in Singapore. Number of women directors was significantly negatively related to Tobin’s Q, ROA and ROE. Leverage level was significantly negatively related to all firm performance’s measures in Malaysia, while only significantly related to Tobin’s Q in Singapore