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Tikki Pang

Publications and source records attributed to Tikki Pang.

At least 37 records · Page 2Linked to original sources
PubMed2003

Vaccines for the prevention of neglected diseases--dengue fever.

Dengue and dengue hemorrhagic fever have spread to all tropical areas of the developing world, but still remain largely neglected diseases. Several promising vaccine candidates in the form of live attenuated and chimeric vaccines have been developed and are currently in human clinical trials. However, significant practical, logistic, and scientific challenges remain before these vaccines can widely and safely be applied to vulnerable populations. Vector control, community education and public health measures must be pursued in parallel with vaccine development.

Dengue↗
PubMed2003

Mimotopes of the Vi antigen of Salmonella enterica serovar typhi identified from phage display peptide library.

The capsular polysaccharide Vi antigen (ViCPS) is an essential virulence factor and also a protective antigen of Salmonella enterica serovar Typhi. A random 12-mer phage-displayed peptide library was used to identify mimotopes (epitope analogues) of this antigen by panning against a ViCPS-specific monoclonal antibody (MAb) ATVi. Approximately 75% of the phage clones selected in the fourth round carried the peptide sequence TSHHDSHGLHRV, and the rest of the clones harbored ENHSPVNIAHKL and other related sequences. These two sequences were also obtained in a similar panning process by using pooled sera from patients with a confirmed diagnosis of typhoid fever, suggesting they mimic immunodominant epitopes of ViCPS antigens. Binding of MAb ATVi to the mimotopes was specifically blocked by ViCPS, indicating that they interact with the same binding site (paratope) of the MAb. Data and reagents generated in this study have important implications for the development of peptide-base diagnostic tests and peptide vaccines and may also provide a better understanding of the pathogenesis of typhoid fever.

Amino Acid Sequence↗
PubMed2003

Impact of pharmacogenomics on neglected diseases of the developing world.

Pharmacogenomics promises to have an important impact on the major health problems of the developing world, especially on neglected infectious diseases such as malaria, tuberculosis, and HIV/AIDS. Its capacity to identify new targets for drug development, together with its potential application in identifying populations who will respond favorably to a particular drug, gives it a unique place as a technology to bridge the genomics divide between rich and poor nations. To realize its true potential, however, significant scientific, legal, ethical, political, and economic challenges need to be overcome. For this to occur, an innovative global approach based on strong collaboration between industry, academia, non-governmental, and international organizations will be required. Simultaneously, more equitable and active participation from developing country researchers themselves is critical in overcoming these challenges.

Communicable Diseases↗
PubMed2002

Increasing genetic diversity of Salmonella enterica serovar typhi isolates from papua new guinea over the period from 1992 to 1999.

Pulsed-field gel electrophoresis (PFGE) of XbaI-digested chromosomal DNA was performed on 133 strains of Salmonella enterica serovar Typhi obtained from Papua New Guinea, with the objective of assessing the temporal variation of these strains. Fifty-two strains that were isolated in 1992 and 1994 were of one phage type, D2, and only two predominant PFGE profiles, X1 and X2, were present. Another 81 strains isolated between 1997 and 1999 have shown divergence, with four new phage types, UVS I (n = 63), UVS (n = 5), VNS (n = 4), and D1 (n = 9), and more genetic variability as evidenced by the multiple and new PFGE XbaI profiles (21 profiles; Dice coefficient, F = 0.71 to 0.97). The two profiles X1 and X2 have remained the stable, dominant subtypes since 1992. Cluster analysis based on the unweighted pair group method using arithmetic averages algorithm identifies two main clusters (at 87% similarity), indicating that the divergence of the PFGE subtypes was probably derived from some genomic mutations of the X1 and X2 subtypes. The majority of isolates were from patients with mild and moderate typhoid fever and had various XbaI profiles. A single isolate from a patient with fatal typhoid fever had a unique X11 profile, while four of six isolates from patients with severe typhoid fever had the X1 pattern. In addition, 12 paired serovar Typhi isolates recovered from the blood and fecal swabs of individual patients exhibited similar PFGE patterns, while in another 11 individuals paired isolates exhibited different PFGE patterns. Three pairs of isolates recovered from three individuals had different phage types and PFGE patterns, indicating infection with multiple strains. The study reiterates the usefulness of PFGE in assessing the genetic diversity of S. enterica serovar Typhi for both long-term epidemiology and in vivo stability and instability within an individual patient.

Bacteriophage Typing↗
PubMed2002

Characterization of Salmonella serovars by PCR-single-strand conformation polymorphism analysis.

PCR-restriction fragment length polymorphism (PCR-RFLP) and PCR-single-strand conformation polymorphism (PCR-SSCP) analyses were carried out on the 1.6-kb groEL gene from 41 strains of 10 different Salmonella serovars. Three HaeIII RFLP profiles were recognized, but no discrimination between the serovars could be achieved by this technique. However, PCR-SSCP analysis of the groEL genes of various Salmonella serovars produced 14 SSCP profiles, indicating the potential of this technique to differentiate different Salmonella serovars (interserovar differentiation). Moreover, PCR-SSCP could differentiate strains within a subset of serovars (intraserovar discrimination), as three SSCP profiles were produced for the 11 Salmonella enterica serovar Enteritidis strains, and two SSCP profiles were generated for the 7 S. enterica serovar Infantis and five S. enterica serovar Newport strains. PCR-SSCP has the potential to complement classical typing methods such as serotyping and phage typing for the typing of Salmonella serovars due to its rapidity, simplicity, and typeability.

Bacterial Typing Techniques↗
PubMed2002

The impact of genomics on global health.

Ensuring that advances in genomics are applied to the health improvement of people living in developing countries is an important contemporary challenge. In the near term, such advances are likely to alleviate infectious diseases, with longer-term benefits envisaged for chronic disorders. To ensure that benefits are shared by developing countries, attention must be paid to complex ethical, legal, social, and economic issues, as well as to public education and engagement. Creative and equitable international mechanisms and goodwill are needed to turn high hopes into reality and allow the use of genomics to reduce health inequities between rich and poor nations.

Chronic Disease↗
PubMedDate not supplied

Overcoming health-systems constraints to achieve the Millennium Development Goals.

Effective interventions exist for many priority health problems in low income countries; prices are falling, and funds are increasing. However, progress towards agreed health goals remains slow. There is increasing consensus that stronger health systems are key to achieving improved health outcomes. There is much less agreement on quite how to strengthen them. Part of the challenge is to get existing and emerging knowledge about more (and less) effective strategies into practice. The evidence base also remains remarkably weak, partly because health-systems research has an image problem. The forthcoming Ministerial Summit on Health Research seeks to help define a learning agenda for health systems, so that by 2015, substantial progress will have been made to reducing the system constraints to achieving the MDGs.

Delivery of Health Care↗