METHODS: A systematic search was conducted for articles published from January 1990 to December 2009 in PubMed/MEDLINE using terms for malaria and 11 target countries (Bhutan, China, North Korea, Indonesia, Malaysia, Philippines, Solomon Islands, South Korea, Sri Lanka, Thailand and Vanuatu). The references were collated and categorized according to subject, Plasmodium species, and whether they contained original or derivative data.
RESULTS: 2,700 articles published between 1990 and 2009 related to malaria in the target countries. The annual output of malaria-related papers increased linearly whereas the overall biomedical output from these countries grew exponentially. The percentage of malaria-related publications was nearly 3% (111/3741) of all biomedical publications in 1992 and decreased to less than 1% (118/12171; p < 0.001) in 2009. Thailand had the highest absolute output of malaria-related papers (n = 1211), followed by China (n = 609) and Indonesia (n = 346). Solomon Islands and Vanuatu had lower absolute numbers of publications, but both countries had the highest number of publications per capita (1.3 and 2.5 papers/1,000 population). The largest percentage of papers concerned the epidemiology and control of malaria (53%) followed by studies of drugs and drug resistance (47%). There was an increase in the proportion of articles relating to epidemiology, entomology, biology, molecular biology, pathophysiology and diagnostics from the first to the second decade, whereas the percentage of papers on drugs, clinical aspects of malaria, immunology, and social sciences decreased.
CONCLUSIONS: The proportion of malaria-related publications out of the overall biomedical output from the 11 target Asian-Pacific countries is decreasing. The discovery and evaluation of new, safe and effective drugs and vaccines is paramount. In addition the elimination of malaria will require operational research to implement and scale up interventions.
Methods: Each 24-well plate of Vero cells infected with all four DENV serotypes, singly, was subjected to treatments with various doses of AR-12. Following 48 h of incubation, inhibitory efficacies of AR-12 against the different DENV serotypes were evaluated by conducting a virus yield reduction assay whereby DENV RNA copy numbers present in the collected supernatant were quantified using qRT-PCR. The underlying mechanism(s) possibly involved in the compound's inhibitory activities were then investigated by performing molecular docking on several potential target human and DENV protein domains.
Results: The qRT-PCR data demonstrated that DENV-3 was most potently inhibited by AR-12, followed by DENV-1, DENV-2 and DENV-4. Our molecular docking findings suggested that AR-12 possibly exerted its inhibitory effects by interfering with the chaperone activities of heat shock proteins.
Conclusions: These results serve as vital information for the design of future studies involving in vitro mechanistic studies and animal models, aiming to decipher the potential of AR-12 as a potential therapeutic option for DENV infection.
MATERIALS AND METHODS: The 344OH employed in present study was synthesized based on the protocol in previous study. The vascular responses towards the cumulative addition of 344OH were evaluated using in vitro rat aortic rings assays.
KEY FINDINGS: The pEC50 and Rmax values were found to be 4.33 ± 0.05 and 106 ± 3.99%, respectively. Results showed that the vasorelaxation of 344OH were predominated by G-protein-coupled muscarinic- (M3) and β2-adrenergic receptors, followed by PGI2/AC/cAMP- and NO/sGC/cGMP-dependent pathways. It was also identified that 344OH employed voltage-activated- (Kv), calcium-activated- (Kca) and inwardly-rectifying (Kir) potassium channels and act as an antagonist for both VOCC and IP3R while regulating the action potential in the vasculature.
SIGNIFICANCE: The different position of hydroxyl substituent located in A-ring of the stilbenoid backbone in 344OH compared to resveratrol resulted in a significant difference in mechanistic actions that lead to 344OH's fast-acting and less time-dependent vasorelaxation behaviour. This has substantially increased the potential of 344OH to be developed as an effective antihypertensive drug in future. Present findings further strengthen our inferences where the SARs study approach should be carried out as the mainstream methodology in future drug development research.
METHODS: Smaller micro tissues (˂150 μm in diameter) mixed with Matrigel were engrafted subcutaneously into NSG mice to generate the passage 1 (P1) patient-derived xenograft. The micro tumours from P1 patient-derived xenograft were then excised and orthotopically xenografted into another batch of NSG mice to generate a metastatic colorectal cancer patient-derived xenograft, P2. Haematoxylin and eosin and immunohistochemistry staining were performed to compare the characters between patient-derived xenograft tumours and primary tumours.
RESULTS: About 16 out of 18 P1 xenograft models successfully grew a tumour for 50.8 ± 5.1 days (success rate 89.9%). Six out of eight P1 xenograft models originating from metastatic patients successfully grew tumours in the colon and metastasized to liver or lung in the NSG recipients for 60.9 ± 4.5 days (success rate 75%). Histological examination of both P1 and P2 xenografts closely resembled the histological architecture of the original patients' tumours. Immunohistochemical analysis revealed similar biomarker expression levels, including CDH17, Ki-67, active β-catenin, Ki-67 and α smooth muscle actin when compared with the original patients' tumours. The stromal components that support the growth of patient-derived xenograft tumours were of murine origin.
CONCLUSIONS: Metastatic patient-derived xenograft mouse model could be established with shorter time and higher success rate. Although the patient-derived xenograft tumours were supported by the stromal cells of murine origin, they retained the dominant characters of the original patient tumours.