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Fulltext Range extension of Christisonia scortechinii from mainland Southeast Asia into Borneo, and notes on the distinction between Aeginetia and Christisonia (Orobanchaceae)

van der Ent A, Wong KM

Bot Stud, 2015 Dec;56(1):28.
PMID: 28510837 DOI: 10.1186/s40529-015-0109-3

BACKGROUND: Christisonia is a little-documented and poorly studied root-parasitic genus in the Orobanchaceae occurring in India, China, Indochina and part of the Malesian region. Recent collection of a Christisonia taxon in Kinabalu Park in Sabah, Borneo, taxonomically identical to earlier Sabah collections that have hitherto not been recorded in the literature, led to an assessment of the taxonomic identity of the species against Christisonia scortechinii, C. siamensis, C. sinensis and related species.
RESULTS: Some taxa in China, Indochina, the Malay Peninsula, and the Philippines are morphologically identical to the Borneo taxon except in the number of calyx lobes, but differ by several distinctive characters from other well-distinguished species in the region. Studies of dried herbarium specimens, augmented by photographic images of different stages of fresh flowering material and a scrutiny of available descriptions confirmed that the calyx has two primary lobes in the bud that may separate into 3-5 portions, giving a variable number of apparent lobes in specimen material collected at different localities. This new scrutiny of the calyx also permitted an improved description of the calyx differences that separate Christisonia and the closely related Aeginetia, which have not been clearly elucidated in the past.
CONCLUSIONS: Christisonia scortechinii Prain (Orobanchaceae), the only species that was described as having an initially spathaceous calyx among species of this root-parasitic genus, is newly recorded for Borneo (including Kinabalu Park, where its presence has been overlooked). The range of the species in mainland Southeast Asia, previously extended from Peninsular Malaysia to Thailand and Vietnam, is here further extended to Laos and China. Christisonia wightii Elmer (relevant to the Philippines) and C. sinensis Beck (China) are reduced to synonymy.
Changes in blood pressure after Messenger RNA COVID-19 vaccination

Ch'ng CC, Ong LM, Wong KM

Med J Malaysia, 2022 Nov;77(6):768-770.
PMID: 36448398

The SARS-Cov-2 (COVID-19) vaccination began in Malaysia in March 2021 among frontliners and healthcare workers. Everyone at our hospital received the tozinameran (BNT162b2) Messenger RNA COVID-19 vaccine. Although hypertension has not been mentioned explicitly as an adverse event, concerns were raised after some healthcare staff observed an increase in their blood pressures. In response to that, the hospital began collecting vital signs during second-dose appointments. Vital signs were measured before, immediately after and 15-30 minutes postvaccination. We report our findings from the institution-wide effort to monitor changes in blood pressure among its staff and respond to any possible unwanted events.
Fulltext Anti-methicillin-resistance Staphylococcus aureus (MRSA) compounds from Bauhinia kockiana Korth. And their mechanism of antibacterial activity

Chew YL, Mahadi AM, Wong KM, Goh JK

BMC Complement Altern Med, 2018 Feb 20;18(1):70.
PMID: 29463252 DOI: 10.1186/s12906-018-2137-5

BACKGROUND: Bauhinia kockiana originates from Peninsular Malaysia and it is grown as a garden ornamental plant. Our previous study reported that this plant exhibited fairly strong antioxidant and antimicrobial activities. This paper focused on the assessment of the antibacterial activity of B. kockiana towards methicillin-resistance Staphylococcus aureus (MRSA), to purify and to identify the antibacterial compounds, and to determine the mechanism of antibacterial activity.
METHODS: Antibacterial activity of B. kockiana flower was evaluated qualitatively and quantitatively using disc diffusion assay and microbroth dilution method. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of extracts were examined. Phytochemical analysis was performed to determine the classes of phytochemicals in the extracts. Bioactivity guided isolation was employed to purify the antibacterial agents and identified via various spectroscopy methods. Scanning electron microscopy (SEM) technique was used to evaluate the antibacterial mechanism of extract and compounds isolated.
RESULTS: B. kockiana flower was found to exhibit fairly strong antibacterial activity towards both strains of MRSA bacteria used, MIC varies from 62.5-250 μg/mL. Tannins and flavonoids have been detected in the phytochemical analysis. Gallic acid and its ester derivatives purified from ethyl acetate extract could inhibit MRSA at 250-500 μg/mL. SEM revealed that the cells have undergone plasmolysis upon treatment with the extract and compounds.
CONCLUSION: Tannins and polyphenols are the antibacterial components towards MRSA in B. kockiana. Massive leakage of the cell content observed in treated cells showed that the phytochemicals have changed the properties of the cell membranes. Amphiphilic nature of the compounds exhibited the antibacterial activity towards MRSA via three stages: (1) cell membrane attachment; (2) cell membrane fluidity modification; and (3) cell membrane structure disruption.
Seroprevalence of Pteropine orthoreovirus in humans remain similar after nearly two decades (2001-2002 vs. 2017) in Tioman Island, Malaysia

Leong WJ, Quek XF, Tan HY, Wong KM, Muhammad HS, Mohamed NA, et al.

J Med Virol, 2022 02;94(2):771-775.
PMID: 34708881 DOI: 10.1002/jmv.27422

Pteropine orthoreovirus (PRV) is an emerging zoonotic respiratory virus that can be transmitted from bats to humans. In Malaysia, aside from PRV2P (Pulau virus) being isolated from Pteropus hypomelanus sampled in Tioman Island, PRV3M (Melaka virus), PRV4K (Kampar virus), and PRV7S (Sikamat virus) were all isolated from samples of patients who reported having a disease spectrum from acute respiratory distress to influenza-like illness and sometimes even with enteric symptoms such as diarrhea and abdominal pain. Screening of sera collected from human volunteers on Tioman Island in 2001-2002 demonstrated that 12.8% (14/109) were positive for PRV2P and PRV3M. Taking all these together, we aim to investigate the serological prevalence of PRV (including PRV4K and PRV7S) among Tioman Island inhabitants again with the assumption that the seroprevalence rate will remain nearly similar to the above reported if human exposure to bats is still happening in the island. Using sera collected from human volunteers on the same island in 2017, we demonstrated seroprevalence of 17.8% (28/157) against PRV2P and PRV3M, respectively. Seropositivity of 11.4% among Tioman Island inhabitants against PRV4K and PRV7S, respectively, was described in this study. In addition, the seroprevalence of 89.5% (17/19), 73.6% (14/19), 63.0% (12/19), and 73.6% (14/19) against PRV2P, PRV3M, PRV4K, and PRV7S, respectively, were observed among pteropid bats in the island. We revealed that the seroprevalence of PRV among island inhabitants remains nearly similar after nearly two decades, suggesting that potential spill-over events in bat-human interface areas in the Tioman Island. We are unclear whether such spillover was directly from bats to humans, as suspected for the PRV3M human cases, or from an intermediate host(s) yet to be identified. There is a high possibility of the viruses circulating among the bats as demonstrated by high seroprevalence against PRV in the bats.