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Fulltext A retrospective review on successful management of Penicillium marneffei infections in patients with advanced HIV in Hospital Sungai Buloh

Nor-Hayati S, Sahlawati M, Suresh-Kumar C, Lee KC

Med J Malaysia, 2012 Feb;67(1):66-70.
PMID: 22582551 MyJurnal

Penicillium marneffei is a dimorphic fungus which commonly causes a life threatening systemic fungal infection in an immunocompromised host. It has been recognized as an AIDS defining illness in Malaysia since the beginning of the HIV pandemic. The presence of various non specific clinical presentations, especially the characteristic umbilicated papular rashes with central necrosis which lead to significant ill health in immunocompromised patients should alarm clinicians to the possibility of Penicillium marneffei infection and prompt investigations accordingly. Simple investigations like blood culture and fungal staining of the skin scrapping can confirm the diagnosis in the majority of cases. Early treatment with appropriate systemic antifungal for a definite duration will significantly decrease the mortality rate from penicilliosis.
Fulltext Role of Phase-Dependent Dielectric Properties of Alumina Nanoparticles in Electromagnetic-Assisted Enhanced Oil Recovery

Adil M, Lee KC, Zaid HM, Manaka T

Nanomaterials (Basel), 2020 Oct 06;10(10).
PMID: 33036153 DOI: 10.3390/nano10101975

The utilization of metal-oxide nanoparticles in enhanced oil recovery (EOR) has generated considerable research interest to increase the oil recovery. Among these nanoparticles, alumina nanoparticles (Al2O3-NPs) have proved promising in improving the oil recovery mechanism due to their prominent thermal properties. However, more significantly, these nanoparticles, coupled with electromagnetic (EM) waves, can be polarized to reduce water/oil mobility ratio and create disturbances at the oil/nanofluid interface, so that oil can be released from the reservoir rock surfaces and travelled easily to the production well. Moreover, alumina exists in various transition phases (γ, δ, θ, κ, β, η, χ), providing not only different sizes and morphologies but phase-dependent dielectric behavior at the applied EM frequencies. In this research, the oil recovery mechanism under EM fields of varying frequencies was investigated, which involved parameters such as mobility ratio, interfacial tension (IFT) and wettability. The displacement tests were conducted in water-wet sandpacks at 95 °C, by employing crude oil from Tapis. Alumina nanofluids (Al2O3-NFs) of four different phases (α, κ, θ and γ) and particle sizes (25-94.3 nm) were prepared by dispersing 0.01 wt. % NPs in brine (3 wt. % NaCl) together with SDBS as a dispersant. Three sequential injection scenarios were performed in each flooding scheme: (i) preflushes brine as a secondary flooding, (ii) conventional nano/EM-assisted nanofluid flooding, and (iii) postflushes brine to flush NPs. Compared to conventional nanofluid flooding (3.03-11.46% original oil in place/OOIP) as incremental oil recovery, EM-assisted nanofluid flooding provided an increase in oil recovery by approximately 4.12-12.90% of OOIP for different phases of alumina. It was established from these results that the recovery from EM-assisted nanofluid flooding is itself dependent on frequency, which is associated with good dielectric behavior of NPs to formulate the oil recovery mechanism including (i) mobility ratio improvement due to an electrorheological (ER) effect, (ii) interfacial disturbances by the oil droplet deformation, and (iii) wettability alteration by increased surface-free energy.
Characterization of oil-palm trunk residue degradation enzymes derived from the isolated fungus, Penicillium rolfsii c3-2(1) IBRL

Lee KC, Arai T, Ibrahim D, Deng L, Murata Y, Mori Y, et al.

Environ Technol, 2016 Jun;37(12):1550-8.
PMID: 26582429 DOI: 10.1080/09593330.2015.1120786

This study characterizes crude enzymes derived from Penicillium rolfsii c3-2(1) IBRL, a mesophilic fungus isolated from the local soil of Malaysia. Prior to enzyme activity evaluation, P. rolfsii c3-2(1) IBRL was inoculated into a broth medium containing oil-palm trunk residues for the preparation of crude enzymes. Oil-palm trunk residues were optimally hydrolysed at pH5.0 and 50°C. P. rolfsii c3-2(1) IBRL-derived crude enzymes displayed higher thermal stability compared with the commercial enzymes, Celluclast 1.5 L and Acellerase 1500. Moreover, the hydrolysing activities of the P. rolfsii c3-2(1) IBRL-derived crude enzymes (xylan, arabinan, and laminarin) were superior compared to that of Celluclast 1.5 L and Acellerase 1500, and exhibit 2- to 3-fold and 3- to 4-fold higher oil-palm trunk residues-hydrolysing specific activity, respectively. This higher hydrolysis efficiency may be attributed to the weak 'lignin-binding' ability of the P. rolfsii c3-2(1) IBRL-derived enzymes compared to the commercial enzymes.
Evaluation of Enzymatic Deinking of Non-impact Ink Laser-Printed Paper Using Crude Enzyme from Penicillium rolfsii c3-2(1) IBRL

Lee KC, Tong WY, Ibrahim D, Arai T, Murata Y, Mori Y, et al.

Appl Biochem Biotechnol, 2017 Jan;181(1):451-463.
PMID: 27596245 DOI: 10.1007/s12010-016-2223-4

Application of microbial enzymes for paper deinking is getting tremendous attention due to the rapidly increasing of waste paper every year. This study reports the deinking efficiency of laser-printed paper by the lignocellulolytic enzyme from Penicillium rolfsii c3-2(1) IBRL strain compared to other enzyme sources as well as commercial available enzymes. High enzymatic deinking efficiency of approximately 82 % on laser-printed paper was obtained by pulp treatment with crude enzyme from P. rolfsii c3-2(1) IBRL. However, this crude enzyme was found to reduce the paper strength properties of the pulp based on the results of tensile, tear and burst indices, most probably due to the cellulose degradation. This was further proven by the low viscosity of paper pulp obtained after enzymatic treatment and increasing of sugar production during the treatment. Balancing to this detrimental effect on paper pulp, high deinking efficiency was achieved within a short period of time, in which the enzymatic treatment was conducted for 30 min that enabled contribution to higher brightness index obtained, thus promoting savings of time and energy consumption, therefore environmental sustainability. Extensive research should be conducted to understand the nature and mechanism of enzymatic deinking process by the crude enzyme from P. rolfsii c3-2(1) IBRL in order to improve paper strength properties.
Chromogenic in situ hybridization technique for detecting porcine circovirus 3 in lung and lymphoid tissues

Tan CY, Lee KC, Chiou MT, Lin CN, Ooi PT

Vet World, 2023;16(7):1444-1450.
PMID: 37621535 DOI: 10.14202/vetworld.2023.1444-1450

BACKGROUND AND AIM: Porcine circovirus 3 (PCV3) was recently reported in Malaysian commercial pig population in 2020 by conventional polymerase chain reaction (PCR), revealing a molecular prevalence of 17.02% in the sampled domestic pig population. This study aims to describe a chromogenic in situ hybridization (ISH) technique using digoxigenin (DIG)-labeled cloned PCV3 open reading frame 1 (ORF1) fragment DNA to detect and localize the PCV3 antigen in formalin-fixed, paraffin-embedded lung, and lymphoid tissue specimens.
MATERIALS AND METHODS: Since PCV3 was mainly detected in lung and lymphoid tissues, we obtained tissue specimens from these organs from the previous Malaysian PCV3 study. Digoxigenin-labeled ISH probes were designed to target a 69 bp region of PCV3 ORF1 spanning from the nucleotide positions (282-350).
RESULTS: Light microscopy analysis revealed that chromogenic staining of PCV3 antigens was visualized within the cytoplasm of pneumocytes and lymphocytes, indicating positive ISH results. The results of molecular detection of PCV3 using PCR and ISH showed a high agreement of 90.91%, including for the negative PCV3 status for all samples.
CONCLUSION: This study reports a chromogenic ISH technique using DIG-labeled probes targeting PCV3 ORF1 to detect PCV3 antigens in lung and lymphoid tissues. Despite the limited availability of PCV3 antibodies, ISH remains relevant for investigating PCV3 replication and pathogenesis and can be used complementarily with PCR for evaluating the localization of antigens in infected tissues.
Efficacy and safety of diphenylcyclopropenone among Chinese patients with steroid resistant and extensive alopecia areata

Luk NM, Chiu LS, Lee KC, Chau CT, Lee VW, Chang M, et al.

J Eur Acad Dermatol Venereol, 2013 Mar;27(3):e400-5.
PMID: 23057682 DOI: 10.1111/jdv.12009

BACKGROUND: Topical immunotherapy has recently been found useful in the treatment of chronic and extensive Alopecia Areata (AA).
OBJECTIVE: To evaluate the efficacy and safety of diphenylcyclopropenone (DPCP) use among Chinese patients with steroid resistant and extensive AA in our institute.
METHODS: The medical records of 31 Chinese patients treated with DPCP were analysed retrospectively. The efficacy, adverse effects, and relapse rate of DPCP treatment were reviewed.
RESULTS: Thirty-one (16 male, 15 female) Chinese patients with extensive, steroid resistant Alopecia Areata and a mean age of 28.9 years (SE 10.4) were treated. The mean age of onset was 17.8 years (SE 8.8) with an average disease duration of 11.2 years (SE 7.7). Ten patients had a history of atopy and 4 had a history of thyroid disease. Nail changes were found in 14 patients and a family history of AA was found in 2 patients. Thirteen patients (41.9%) had experienced total hair loss. Two patients abandoned the treatment due to severe side effects. Of the remaining 29 patients, 4 (13.8%), 7 (24.1%), 5 (17.2%), and 13 (44.8%) achieved >90% complete response, >50-90% partial response, >10-50% minimal response, and <10% no response hair regrowth, respectively. Adverse effects included pruritus, erythema, vesiculation, scaling, cervical lymphadenopathy, dyspigmentation and urticarial reactions. Relapse occurred (>25% hair loss) in 69.23% of patients after 18 months of follow up.
CONCLUSIONS: DPCP is an effective and tolerable treatment for Chinese patients with extensive, steroid resistant AA.
Fulltext Homalomena pineodora essential oil nanoparticle inhibits diabetic wound pathogens

Rozman NAS, Tong WY, Leong CR, Anuar MR, Karim S, Ong SK, et al.

Sci Rep, 2020 02 24;10(1):3307.
PMID: 32094395 DOI: 10.1038/s41598-020-60364-0

Essential oil of Homalomena pineodora inhibits diabetic pathogens; however, the activity was not sustainable when applied as wound dressing. This study aims to synthesise the essential oil nanoparticle using chitosan. The nanoparticles were synthesised with ion gelation method, confirmed by spectroscopic analysis. The spherical nanoparticles display a size of 70 nm, with strong surface charge of +24.10 mV. The nanoparticles showed an initial burst release followed by a slow release pattern for 72 h, following the first order of kinetic. The release behaviour was ideal for wound dressing. The antimicrobial activity was broad spectrum. The formation of nanoparticle enhanced the antimicrobial efficacy of the essential oil. The nanoparticle also showed a concentration-dependent killing behaviour on time-kill assay. In the 3D collagen wound models, the nanoparticles reduced the microbial growth by 60-80%. In conclusion, H. pineodora nanoparticles showed pharmaceutical potential in inhibiting microbial growth on diabetic ulcers.
Fulltext Toward Sustainable Environmental Quality: Priority Research Questions for Asia

Leung KMY, Yeung KWY, You J, Choi K, Zhang X, Smith R, et al.

Environ Toxicol Chem, 2020 Aug;39(8):1485-1505.
PMID: 32474951 DOI: 10.1002/etc.4788

Environmental and human health challenges are pronounced in Asia, an exceptionally diverse and complex region where influences of global megatrends are extensive and numerous stresses to environmental quality exist. Identifying priorities necessary to engage grand challenges can be facilitated through horizon scanning exercises, and to this end we identified and examined 23 priority research questions needed to advance toward more sustainable environmental quality in Asia, as part of the Global Horizon Scanning Project. Advances in environmental toxicology, environmental chemistry, biological monitoring, and risk-assessment methodologies are necessary to address the adverse impacts of environmental stressors on ecosystem services and biodiversity, with Asia being home to numerous biodiversity hotspots. Intersections of the food-energy-water nexus are profound in Asia; innovative and aggressive technologies are necessary to provide clean water, ensure food safety, and stimulate energy efficiency, while improving ecological integrity and addressing legacy and emerging threats to public health and the environment, particularly with increased aquaculture production. Asia is the largest chemical-producing continent globally. Accordingly, sustainable and green chemistry and engineering present decided opportunities to stimulate innovation and realize a number of the United Nations Sustainable Development Goals. Engaging the priority research questions identified herein will require transdisciplinary coordination through existing and nontraditional partnerships within and among countries and sectors. Answering these questions will not be easy but is necessary to achieve more sustainable environmental quality in Asia. Environ Toxicol Chem 2020;39:1485-1505. © 2020 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.
Asian Pacific Association for the Study of the Liver clinical practice guidelines on liver transplantation

Kim DS, Yoon YI, Kim BK, Choudhury A, Kulkarni A, Park JY, et al.

Hepatol Int, 2024 Apr;18(2):299-383.
PMID: 38416312 DOI: 10.1007/s12072-023-10629-3

Liver transplantation is a highly complex and challenging field of clinical practice. Although it was originally developed in western countries, it has been further advanced in Asian countries through the use of living donor liver transplantation. This method of transplantation is the only available option in many countries in the Asia-Pacific region due to the lack of deceased organ donation. As a result of this clinical situation, there is a growing need for guidelines that are specific to the Asia-Pacific region. These guidelines provide comprehensive recommendations for evidence-based management throughout the entire process of liver transplantation, covering both deceased and living donor liver transplantation. In addition, the development of these guidelines has been a collaborative effort between medical professionals from various countries in the region. This has allowed for the inclusion of diverse perspectives and experiences, leading to a more comprehensive and effective set of guidelines.