Molecular detection of human adenovirus among hospitalized patients with lower respiratory tract infection in Hospital Sungai Buloh, Malaysia

Human adenovirus (HAdV) is one of the common pathogens that are responsible for a wide variety of infectious diseases. There are about 54 different adenovirus serotypes that are responsible for respiratory infections in humans. The prevalence of lower respiratory tract infection (LRTI) - associated with HAdV varies throughout different regions. The prevalence of HAdV in Malaysia is rarely investigated and reported despite severity of infection worldwide. This study was undertaken to identify the HAdV types associated with lower respiratory tract infection (LRTI) in Hospital Sungai Buloh, Malaysia between April 2013 until January 2014, a total of 210 specimens were collected from patients hospitalized with LRTI. Human adenovirus was detected using polymerase chain reaction (PCR). The positive products were sequenced and phylogenetic analysis of the virus was performed. Eighteen of 210 specimens (8.57%) were positive with HAdV infection. Based on the phylogenetic analysis study, HAdV-7 strains were the most common serotype with 11 cases, followed by HAdV-1, HAdV-2 and HAdV-4 with 2 cases each and one case of HAdV-5. The HAdV strains in this study were closely related to strains in Singapore and India. In this study, HAdV infection from LRTI patients in Hospital Sungai Buloh Malaysia were caused by different types of adenovirus mainly HAdV-7. This study will become a reference for further epidemiological study in this country.

Dillenia suffruticosa exhibited antioxidant and cytotoxic activity through induction of apoptosis and G2/M cell cycle arrest

ETHNOPHARMACOLOGICAL RELEVANCE

Dillenia suffruticosa (Family: Dilleniaceae) locally known as Simpoh air has been reported to be used traditionally to treat cancerous growth. Therefore, the present study was attempted to investigate the antioxidant and cytotoxic properties of different parts (root, flower, fruit and leaf) of D. suffruticosa extracts.

METHODS AND MATERIALS

In this study, direct solvent extraction (aqueous and methanol) from different parts of D. suffruticosa (root, flower, fruit and leaf) were carried out. Antioxidant activities of D. suffruticosa extract were determined by using DPPH, ABTS FRAP and β-carotene bleaching assays. Cytotoxicity and cell cycle arrest of the active extract were determined using MTT assay and flow cytometer, respectively. Sequential solvent extraction (hexane, DCM, EtOAc, and MeOH) were also carried out in root of D. suffruticosa to further evaluate the antioxidant and cytotoxic activity of the different solvent extracts.

RESULTS

Methanol (MeOH) root extract showed the highest TPC, antioxidant and cytotoxic activities (especially towards HeLa) compared to others (P<0.05). Based on the results, sequential solvent extraction (hexane, DCM, EtOAc and MeOH) was carried out in the roots of D. suffruticosa. MeOH extract exhibited the highest antioxidant activities among others and significantly correlated (P<0.05) with TPC, suggesting the important contribution of phenolic compounds to its antioxidant activity. On the other hand, the DCM and EtOAc exhibited higher cytotoxic activity to selected cancer cells (HeLa, MCF-7, MDA-MB-231, A549 and HT29) compared to others. In short, there is no established correlation between antioxidant and cytotoxic activities of D. suffruticosa extracts indicating that an agent with high antioxidant activities will not necessarily possesses good cytotoxic activities in return. Qualitative phytochemical screening of D. suffruticosa extracts suggested the presence of saponins, triterpenes, sterols, and polyphenolic compounds which are believed to contribute to the cytotoxic activities.

CONCLUSION

It is suggested that the cytotoxicity of the active extracts in HeLa was due to the induction of apoptosis and cell cycle arrest at G2/M.