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.
OBJECTIVES: The study was undertaken to evaluate the possibility to isolate bacteriolytic bacteriophages against S.aureus from raw sewage water and examine their efficacy as antimicrobial agents in vitro.
METHODS: Bacteriophages were isolated from the raw sewage using the agar overlay method. Isolated bacteriophages were plaque purified to obtain homogenous bacteriophage isolates. The host range of the bacteriophages was determined using the spot test assay against the 25 MRSA and 36 MSSA isolates obtained from the Sarawak General Hospital. Staphylococcus saprophyticus, Staphylococcus sciuri and Staphylococcus xylosus were included as non-SA controls. The identity of the bacteriophages was identified via Transmission Electron Microscopy and genomic size analysis. Their stability at different pH and temperature were elucidated.
RESULTS: A total of 10 lytic bacteriophages infecting S.aureus were isolated and two of them namely ΦNUSA-1 and ΦNUSA-10 from the family of Myoviridae and Siphoviridae respectively exhibited exceptionally broad host range against >80% of MRSA and MSSA tested. Both bacteriophages were specific to S.aureus and stable at both physiologic pH and temperature.
CONCLUSION: This study demonstrated the abundance of S.aureus specific bacteriophages in raw sewage. Their high virulence against both MSSA and MRSA is an excellent antimicrobial characteristic which can be exploited for bacteriophage therapy against MRSA.
Methods: This study investigated the cytotoxic effect of the venom from Trimeresurus purpureomaculatus, the mangrove pit viper (also known as shore pit viper) which is native in Malaysia, across a panel of human cancer cell lines from breast, lung, colon and prostate as well as the corresponding normal cell lines of each tissue.
Results: The venom exhibited dose-dependent cytotoxic activities on all cell lines tested, with median inhibition concentrations (IC50) ranging from 0.42 to 6.98 µg/mL. The venom has a high selectivity index (SI = 14.54) on breast cancer cell line (MCF7), indicating that it is significantly more cytotoxic toward the cancer than to normal cell lines. Furthermore, the venom was fractionated using C18 reversed-phase high-performance liquid chromatography and the anticancer effect of each protein fraction was examined. Fraction 1 that contains a hydrophilic low molecular weight (approximately 7.5 kDa) protein was found to be the most cytotoxic and selective toward the breast cancer cell line (MCF7). The protein was identified using liquid chromatography-tandem mass spectrometry as a venom disintegrin, termed purpureomaculin in this study.
Conclusion: Taken together, the findings revealed the potent and selective cytotoxicity of a disintegrin protein isolated from the Malaysian T. purpureomaculatus venom and suggested its anticancer potential in drug discovery.
OBJECTIVES: Pioneering research on molecular mechanisms underlying the viral transmission, molecular pathogenicity, and potential treatments will be highlighted in this review. The development of antiviral drugs specific to SARS-CoV-2 is a complicated and tedious process. To accelerate scientific discoveries and advancement, researchers are consolidating available data from associated coronaviruses into a single pipeline, which can be readily made available to vaccine developers.
METHODS: In order to find studies evaluating the COVID-19 virus epidemiology, repurposed drugs and potential vaccines, web searches and bibliographical bases have been used with keywords that matches the content of this review.
RESULTS: The published results of SARS-CoV-2 structures and interactomics have been used to identify potential therapeutic candidates. We illustrate recent publications on SARS-CoV-2, concerning its molecular, epidemiological, and clinical characteristics, and focus on innovative diagnostics technologies in the production pipeline. This objective of this review is to enhance the comprehension of the unique characteristics of SARS-CoV-2 and strengthen future control measures.
Lay Summary: An innovative analysis is evaluating the nature of the COVID-19 pandemic. The aim is to increase knowledge of possible viral detection methods, which highlights several new technology limitations and advantages. We have assessed some drugs currently for patients (Lopinavir, Ritonavir, Anakinra and Interferon beta 1a), as the feasibility of COVID-19 specific antivirals is not presently known. The study explores the race toward vaccine development and highlights some significant trials and candidates in various clinical phases. This research addresses critical knowledge gaps by identifying repurposed drugs currently under clinical trials. Findings will be fed back rapidly to the researchers interested in COVID 19 and support the evidence and potential of possible therapeutics and small molecules with their mode of action.