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Fulltext Molecular detection of bacterial endosymbionts in acanthamoeba spp.: a preliminary study

Faizah, M. H., Anisah, N., Yusof, S., Noraina, A. R., Adibah, M. R.

Medicine & Health, 2017;12(2):286-292.
MyJurnal

Acanthamoeba spp. merupakan ameba hidup bebas yang biasa ditemui
di persekitaran. Ia merupakan agen penyebab keratitis Acanthamoeba (AK)
dan ensefalitis ameba bergranuloma (GAE). Ameba ini juga mampu menjadi
perumah kepada pelbagai bakteria termasuklah yang bersifat patogenik seperti
Mycobacterium, Legionella dan Staphylococcus aureus rintang metisilin (MRSA).
Berdasarkan maklumat ini, satu kajian dijalankan untuk mengesan kehadiran tiga
bakteria endosimbion berkepentingan perubatan di dalam Acanthamoeba spp. yang
telah dipencilkan dari bolong penghawa dingin yang terdapat di wad and dewan
bedah di Pusat Perubatan Universiti Kebangsaan Malaysia. Kehadiran bakteria
endosimbion ini disaring menggunakan pasangan primer khusus bagi setiap genus
menggunakan reaksi rantai polimerase (PCR) konvensional dan disahkan dengan
analisis penjujukan. Dua puluh sembilan (80.56%) pencilan Acanthamoeba spp.
didapati mengandungi bakteria endosimbion patogenik yang disasarkan dengan
sekurang-kurangnya satu genus bakteria bagi setiap pencilan. Mycobacterium
(82.76 %) adalah bakteria yang paling banyak dikesan, diikuti dengan Legionella sp.
(65.52 %) dan Pseudomonas spp. (62.07 %). Tiada bakteria MRSA dikesan daripada
mana-mana pencilan dalam kajian ini. Dua endosimbion Mycobacterium yang
dikenalpasti telah dikelompokkan ke dalam strain Mycobacterium tuberculosis.
Kami membuat kesimpulan bahawa, kebanyakan Acanthamoeba berpotensi untuk
menjadi perumah bagi pelbagai bakteria patogenik, namun implikasi interaksi ini
terhadap patogenisiti kedua-dua organisma masih kurang jelas dan memerlukan
penyelidikan yang lebih lanjut.
Effect of glyphosate-based herbicide on early life stages of Java medaka (Oryzias javanicus): a potential tropical test fish

Yusof S, Ismail A, Alias MS

Mar Pollut Bull, 2014 Aug 30;85(2):494-8.
PMID: 24731878 DOI: 10.1016/j.marpolbul.2014.03.022

Glyphosate is globally a widely used herbicide, yet there is little information on their toxicity to marine fishes. Java medaka, a small tropical fish native to coastal areas in several Southeast Asian countries, is viewed as a suitable candidate for toxicity test and thus was used for this study. Java medaka adults were cultured in the laboratory and the fertilized eggs of the F2 generation were exposed to different concentrations of glyphosate-based herbicide (100, 200, 300, 400 and 500 ppm) until they hatched. The survival and hatching rates of the embryos, changes in the heart rate and morphological impairments were recorded. Generally, survival and hatching percentage decreased as glyphosate concentration increased. Absence of pectoral fin(s) and cornea, permanently bent tail, irregular shaped abdomen, and cell disruption in the fin, head and abdomen are among the common teratogenic effects observed. Furthermore, risk factor also increased with the increased in glyphosate concentrations.
Fulltext A study of the nature and level of trust between patients and healthcare providers, its dimensions and determinants: a scoping review protocol

Rasiah S, Jaafar S, Yusof S, Ponnudurai G, Chung KPY, Amirthalingam SD

BMJ Open, 2020 Jan 23;10(1):e028061.
PMID: 31980505 DOI: 10.1136/bmjopen-2018-028061

INTRODUCTION: The aim of this scoping review is to systematically search the literature to identify the nature and or level of trust between the patient, the users of health services (eg, clients seeking health promotion and preventive healthcare services) and the individual healthcare providers (doctors, nurses and physiotherapists/ occupational therapists), across public and private healthcare sectors, at all levels of care from primary through secondary to tertiary care. It also aims to identify the factors that influence trust between patients, users of health services (clients) and providers of healthcare at all levels of care from primary care to tertiary care, and across all health sectors (public and private). The study will also identify the tools used to measure trust in the healthcare provider.
METHODS AND ANALYSIS: The scoping review will be conducted based on the methodology developed by Arksey and O'Malley's scoping review methodology, and Levac et al 's methodological enhancement. An experienced information specialist (HM) searched the following databases MEDLINE, EMBASE, the Cochrane Library, Cumulative Index to Nursing and Allied Health Literature. The search terms were both keywords in the title and/or abstract and subject headings (eg, MeSH, EMTREE) as appropriate. Search results were downloaded, imported and stored into a 'Refworks' folder specifically created for reference management. The preliminary search was conducted between 7 December 2017 and 14 December 2017. Quantitative methods using content analysis will be used to categorise study findings on factors associated with trust between patients, clients and healthcare providers. The collection of studies will be also examined for heterogeneity. Qualitative analysis on peer reviewed articles of qualitative interviews and focus group discussion will be conducted; it allows clear identification of themes arising from the data, facilitating prioritisation, higher order abstraction and theory development. A consultation exercise with stakeholders may be incorporated as a knowledge translation component of the scoping study methodology.
ETHICS AND DISSEMINATION: Ethical approval will be obtained for the research project from the Institutional Review Board. The International Medical University will use the findings of this scoping review research to improve the understanding of trust in healthcare, in its endeavour to improve health services delivery in its healthcare clinics and hospitals, and in its teaching and learning curriculum. The findings will also help faculty make evidence based decisions to focus resources and research as well as help to advance the science in this area. Dissemination of the results of the scoping review will be made through peer-reviewed publications, research reports and presentations at conferences and seminars.
Effect of non-meat proteins, soy protein isolate and sodium caseinate, on the textural properties of chicken bologna

Yusof SC, Babji AS

Int J Food Sci Nutr, 1996 Jul;47(4):323-9.
PMID: 8844254

Nine formulations were processed into bologna with different ratios of soy protein isolate (SPI):sodium caseinate (SCA), i.e. 1:1, 1:2.5, 1:5, 5:1, 5:2.5, 5:5, 10:1, 10:2.5 and 10:5. The products were evaluated for yields, emulsion stability, physical measurements (shearforce-kgf and folding test) and taste panel evaluation. Formulations with 5:1 and 5:5 SPI:SCA had lower liquid loss resulting in higher yields while the others had poor emulsion stability and high liquid loss. Firmer texture was exhibited by formulations 1:1, 5:1 and 10:1 SPI:SCA but formulation with 1:1 SPI:SCA showed better gelation followed by 1:2.5, 1:5, 5:1, and 5:2.5. The other formulations had poor gelation and binding properties, especially formulation with 10:5 SPI:SCA. Sensory evaluation was carried out using 30 untrained panelists. Attributes evaluated were aroma, texture, chewiness, juiciness, saltiness, chicken taste and overall acceptance. Formulation with 5:1 SPI:SCA was more acceptable for texture, chicken taste and overall acceptance while formulation with 1:1 SPI:SCA was more acceptable for the chewiness, juiciness and saltiness attributes. There was no significant difference (P > 0.05) in aroma attribute, for all formulations.
Fulltext N-glycosylation and expression in human tissues of the orphan GPR61 receptor

Kozielewicz P, Alomar H, Yusof S, Grafton G, Cooper AJ, Curnow SJ, et al.

FEBS Open Bio, 2017 12;7(12):1982-1993.
PMID: 29226084 DOI: 10.1002/2211-5463.12339

A number of members of the G protein-coupled receptor class of cell surface receptors are 'orphans' with no known endogenous ligand. One of these orphan receptors is GPR61; there are little data about its expression in human cells and tissues. In this study, we investigated the post-translational modification of GPR61 by N-glycosylation at an identified consensus N-glycosylation site (N12) and the impact of this modification upon the subcellular expression of the protein. The N-glycosylation inhibitor tunicamycin reduced the apparent molecular weight of immunoreactivity associated with myc-tagged GPR61 by 1-2 kDa, which was comparable to the evident molecular weight of the myc-tagged N12S GPR61 mutant with disrupted consensus N-glycosylation site. Analysis of GPR61 expression demonstrated that tunicamycin treatment reduced considerably heterologous expression of GPR61 in the cell membrane despite the N12S GPR61 mutant being readily expressed at the cell surface. These results demonstrate that GPR61 is subject to N-glycosylation but suggest this is not a prerequisite for cell surface expression, although N-glycosylation of other proteins may be important for cell membrane expression of GPR61. Expression of GPR61 protein was demonstrated at the cellular level in human hippocampus and human peripheral blood mononuclear cells. In the latter, there was a significantly higher expression of GPR61 in the Th17 cell subset in comparison with resting CD4+ cells, which may point toward a potential role for the GPR61 receptor in autoimmune diseases. This is the first report that GPR61 protein is subject to post-translational modification and is expressed in immune cell subsets and the hippocampus. These findings will help guide studies to investigate the function of GPR61.
Clinical features of allergic rhinitis and skin prick test analysis based on the ARIA classification: a preliminary study in Malaysia

Asha'ari ZA, Yusof S, Ismail R, Che Hussin CM

Ann Acad Med Singap, 2010 Aug;39(8):619-24.
PMID: 20838703

INTRODUCTION: Allergic rhinitis (AR) is a prevalent disease worldwide but is still underdiagnosed in many parts of Asia. We studied the clinical profiles of AR patients in our community based on the new ARIA classification and investigated the aetiological allergens using a skin prick test.
MATERIALS AND METHODS: In 2008, 142 newly diagnosed patients with AR were seen and underwent skin prick testing with 90 patients completing the study.
RESULTS: Intermittent mild and moderate/severe AR were evident in 10% and 21.1% of the patients, while persistent mild and moderate/severe were seen in 20% and 48.9%, respectively. Rhinitis and asthma co-morbidity occurred in 28.8% with asthma incidence significantly higher in persistent AR (P = 0.002). There was no significant association between AR severity, city living and asthma co-morbidity. Nasal itchiness and sneezing were the main presenting complaints and were more common in intermittent AR (P <0.05). Sleep disturbance was associated with moderate-severe AR (P <0.05). Polypoidal mucosa was associated with asthma co-morbidity (P <0.05). Monosensitivity reaction occurred in 12.2% of patients and was associated with fungi sensitivity (P <0.05). Majority of patients were oligosensitive (52.8%) and polysensitive (34.4%) and were significantly associated with moderate-severe persistent AR (P <0.01). The highest positive skin prick reaction and the largest average wheal diameter were for the house dust mites and cat allergen (P <0.05).
CONCLUSION: Our results reflected the AR profiles in our country, which was comparable with typical profiles of the neighbouring country and other Mediterranean countries with a similar temperate climate.
Fulltext Intestinal parasitic infections in man: a review

Norhayati M, Fatmah MS, Yusof S, Edariah AB

Med J Malaysia, 2003 Jun;58(2):296-305; quiz 306.
PMID: 14569755

Intestinal parasites of importance to man are Enterobius vermicularis, the soil-transmitted helminthes (STH)--Ascaris lumbricoides Tricburis trichiura, bookworms (Necator americans/Ancylostoma duodenale) and Strongyloides stercoralis and the protozoa Entamoeba histolytica and Giardia duodenalis. Other protozoa such as Cryptosporidium sp. and Isopora sp. are becoming important in causing prolonged diarrhea in immunocompromised patients. It is estimated that almost 1 billion, 500 million and 900 million people worldwide are infected by the major nematode species--A. lumbricoides, T. trichiura and hookworms respectively. Most of the infections are endemic and widely distributed throughout poor and socio-economically deprived communities in the tropics and subtropics. Environmental, socio-economic, demographic and health-related behavior is known to influence the transmission and distribution of these infections. In giardiasis, one study indicates that age < or = 12 years and the presence of family members infected with Giardia were risk factors for infection. Most of the infections occur in children and both genders are equally affected. Epidemiological studies of STH infections have shown that the prevalence and intensity of infection are highest among children 4-15 years of age. The frequency of distribution of STH infections is over-dispersed and highly aggregated. areas reinfection can occur as early as 2 months post-treatment, and by 4 months, almost half of the population treated become reinfected. By 6 months the intensity of infection was similar to pretreatment level.
Fulltext Interactions between marine megafauna and plastic pollution in Southeast Asia

Omeyer LCM, Duncan EM, Abreo NAS, Acebes JMV, AngSinco-Jimenez LA, Anuar ST, et al.

Sci Total Environ, 2023 May 20;874:162502.
PMID: 36868274 DOI: 10.1016/j.scitotenv.2023.162502

Southeast (SE) Asia is a highly biodiverse region, yet it is also estimated to cumulatively contribute a third of the total global marine plastic pollution. This threat is known to have adverse impacts on marine megafauna, however, understanding of its impacts has recently been highlighted as a priority for research in the region. To address this knowledge gap, a structured literature review was conducted for species of cartilaginous fishes, marine mammals, marine reptiles, and seabirds present in SE Asia, collating cases on a global scale to allow for comparison, coupled with a regional expert elicitation to gather additional published and grey literature cases which would have been omitted during the structured literature review. Of the 380 marine megafauna species present in SE Asia, but also studied elsewhere, we found that 9.1 % and 4.5 % of all publications documenting plastic entanglement (n = 55) and ingestion (n = 291) were conducted in SE Asian countries. At the species level, published cases of entanglement from SE Asian countries were available for 10 % or less of species within each taxonomic group. Additionally, published ingestion cases were available primarily for marine mammals and were lacking entirely for seabirds in the region. The regional expert elicitation led to entanglement and ingestion cases from SE Asian countries being documented in 10 and 15 additional species respectively, highlighting the utility of a broader approach to data synthesis. While the scale of the plastic pollution in SE Asia is of particular concern for marine ecosystems, knowledge of its interactions and impacts on marine megafauna lags behind other areas of the world, even after the inclusion of a regional expert elicitation. Additional funding to help collate baseline data are critically needed to inform policy and solutions towards limiting the interactions of marine megafauna and plastic pollution in SE Asia.
Solid-phase microextraction for determining twelve orange flavour compounds in a model beverage emulsion

Mirhosseini H, Tan CP, Yusof S, Hamid NS

Phytochem Anal, 2008 Sep-Oct;19(5):429-37.
PMID: 18435528 DOI: 10.1002/pca.1068

Solid-phase microextraction (SPME) coupled to gas chromatography has been applied for the headspace analysis (HS) of 12 target flavour compounds in a model orange beverage emulsion. The main volatile flavour compounds studied were: acetaldehyde, ethyl acetate, alpha-pinene, ethyl butyrate, beta-pinene, myrcene, limonene, gamma-terpinene, octanal, decanal, linalool and citral (neral plus geranial). After screening the fibre type, the effect of other HS-SPME variables such as adsorption temperature (25-55 degrees C), extraction time (10-40 min), sample concentration (1-100% w/w), sample amount (5-10 g) and salt amount (0-30% w/w) were determined using a two-level fractional factorial design (2(5-2)) that was expanded further to a central composite design. It was found that an extraction process using a carboxen-polydimethylsiloxane fibre coating at 15 masculineC for 50 min with 5 g of diluted emulsion 1% (w/w) and 30% (w/w) of sodium chloride under stirring mode resulted in the highest HS extraction efficiency. For all volatile flavour compounds, the linearity values were accurate in the concentration ranges studied (r(2) > 0.97). Average recoveries that ranged from 90.3 to 124.8% showed a good accuracy for the optimised method. The relative standard deviation for six replicates of all volatile flavour compounds was found to be less than 15%. For all volatile flavour compounds, the limit of detection ranged from 0.20 to 1.69 mg/L.
Acute toxicity test of copper pyrithione on Javanese medaka and the behavioural stress symptoms

Mohamat-Yusuff F, Sarah-Nabila AG, Zulkifli SZ, Azmai MNA, Ibrahim WNW, Yusof S, et al.

Mar Pollut Bull, 2018 Feb;127:150-153.
PMID: 29475647 DOI: 10.1016/j.marpolbul.2017.11.046

This study was conducted to investigate the median lethal concentration (LC50) of copper pyrithione (CuPT) at 96-hr exposure on adult Javanese medaka (Oryzias javanicus) in revealing toxicological effects of CuPT contamination in the tropical area. Wild stock fishes were acclimatized for 14-days prior analysis. Triplicate of test tanks for seven test concentrations were placed with ten fishes each, this includes two control tanks. The behaviour of the tested fishes was manually observed through a camera. The LC50 of CuPT at 96-h was found to be 16.58mg/L. Tested fishes swam slowly in vertical movement and swam fast towards food during feeding time as the sign of stress behaviour. Meanwhile, fishes in the two control groups swam actively in a horizontal manner and no excitement during feeding time. No mortality in control groups. Results indicate CuPT to be toxic to Javanese medaka at low concentration and caused behavioural stress.
Fulltext Epidemiological screening of lymphatic filariasis among immigrants using dipstick colloidal dye immunoassay

Wan Omar A, Sulaiman O, Yusof S, Ismail G, Fatmah MS, Rahmah N, et al.

Malays J Med Sci, 2001 Jul;8(2):19-24.
PMID: 22893756

We have recently reported that a dipstick colloidal dye immunoassay (DIA) that detect parasite antigens in human serum is sensitive and specific for the diagnosis of active infection of lymphatic filariasis. Rabbit polyclonal antibodies (RbBmCAg) labelled with a commercial dye, palanil navy blue was used to detect filarial antigenemia among Indonesian and Bangladeshi immigrant workers (N= 630) at oil palm estates at Hulu Trengganu District, Peninsular Malaysia. Microfilaremia with Brugia malayi were detected in 51 (8.10 %) individuals, of which 42 (6.67 %) were among the Indonesians and 9 (1.98 %) among the Bangladeshis. Microfilaremia with Wuchereria bancrofti were detected in 33 (5.24 %) individuals of which 15 (2.38 %) were among the Indonesians and 18 (2.86 %) among the Bangladeshis workers. The DIA detected 96 (15.24 %) antigenemic cases which comprise of all the microfilaremic cases and 15 (2.38 %) amicrofilaremic cases. The amicrofilaremic cases with filarial antigenemia consisted of 9 (1. 43 %) Indonesians and 6 (0.95%) Bangladeshis. We have used 6 ul of the RbBmCAg and diluted (1:10) patients' sera per dipstick which make the DIA reagent conservative. The DIA is a rapid test and can be read in approximate 2 hours.. Additionally, coloured dots developed in the DIA can be qualitatively assessed visually for intensity. The DIA does not require sophisticated equipment or radioactivity, and therefore suitable for field application.
Lactobacilli reduce recurrences of vaginal candidiasis in pregnant women: a randomized, double-blind, placebo-controlled study

Ang XY, Chung FY, Lee BK, Azhar SNA, Sany S, Roslan NS, et al.

J Appl Microbiol, 2021 May 22.
PMID: 34022103 DOI: 10.1111/jam.15158

AIMS: The aim of this study was to investigate the effects of lactobacilli strains in preventing the recurrences of vaginal candidiasis (VC) in 78 pregnant women with VC (lactobacilli, n = 39; placebo, n = 39) and the potential benefits on quality of life.
METHODS AND RESULTS: The lactobacilli putative probiotic (SynForU-HerCare; two capsules/day of 9·5 log CFU per capsule) or placebo was administered for 8-weeks in a randomized, double-blind, placebo-controlled study. Subjects were assessed for vaginal and gut health conditions at baseline, week-4 and week-8 via questionnaires. The vulvovaginal symptom questionnaire not only covered aspects pertaining to vulvovaginal symptoms but also the quality of life impacts such as emotional, social and sexual. The administration of lactobacilli reduced symptoms of irritation (P = 0·023) and discharge (P = 0·011) starting week-4 and continued after week-8 (P
Lactobacillus probiotics restore vaginal and gut microbiota of pregnant women with vaginal candidiasis

Ang XY, Roslan NS, Ahmad N, Yusof SM, Abdullah N, Nik Ab Rahman NN, et al.

Benef Microbes, 2023 Nov 23;14(5):421-431.
PMID: 38350486 DOI: 10.1163/18762891-20220103

The development of probiotics has now included the areas along the gut-vaginal axis. We thus aimed to investigate the effects of lactobacilli probiotic to modulate and restore vaginal and gut microbiota of pregnant women with vaginal candidiasis (VC). A randomised, double-blind and placebo-controlled study was performed in 78 pregnant women with VC. Patients were randomised to either the probiotic (SynForU-HerCare) or placebo which were administered at baseline and continued for 8-weeks (two capsules/day of 9.5 log cfu/capsule). Microbiota profiles were assessed at time points of weeks-0, 4 and 8 for high vaginal swab and faecal samples. Shannon diversity index showed that after 8-weeks amid VC, a shift in microbial community compositional changes occurred in the high vaginal region at both genus (P=0.025) and species (P=0.044) levels, where the administration of probiotic prevented such a shift. These changes were mainly attributed to a decreased in abundance of Lactobacillus (P=0.042) accompanied by increased abundance of Prevotella (P=0.002) and Atopobium (P=0.002) in the placebo group while the probiotic group remained unchanged over time. The administration of probiotics also prevented a reduced abundance of faecal phylum Firmicutes after 8-weeks as seen in the placebo group (P<0.0001), which also showed reduction at subsequent taxonomic levels of class, family, genera and species. VC has not only altered the microbiota of vagina regions but also gut microbiota profiles, causing lessening of gut microbiota that are crucial for gut nutrient availability, protection and immunity. The administration of lactobacilli probiotics has prevented such a shift, leading to better modulated gut and vaginal microenvironment amid VC. The study was registered at ClinicalTrials.gov: identifier number NCT03940612.
Fulltext Coronary heart disease mortality in peninsular Malaysia

Yusof SM, Margetts BM

Med J Malaysia, 1995 Jun;50(2):194-6.
PMID: 7565197
Fulltext Marine polychaete Namalycastis sp. extracts enhance proliferation and regeneration of mice 3T3 fibroblast and MCR-5 human fibroblast cells

Ghazaly MM, Lee GE, Shaipulah NFM, Ibrahim YS, Mohammed A

Saudi J Biol Sci, 2024 Jan;31(1):103883.
PMID: 38125737 DOI: 10.1016/j.sjbs.2023.103883

The Nereidid worm is a marine polychaete commonly found near the Nipa palm (Nypa fructicans) along the mangrove estuary. Recently, many usages have been documented for this polychaete family. Nevertheless, the true potentials of these marine worms, especially Namalycastis sp., from the medical perspective are still unknown. The current study investigated the cytotoxicity effect of Namalycastis sp. crude extracts on mice 3T3 fibroblast cells and human lung MRC-5 fibroblast cells. Thirteen concentrations (2, 4, 8, 16, 31, 63 µg/mL and 0.1, 0.3, 0.5, 1, 2, 4, 8 mg/mL) of the extracts were used as a treatment for 24 h, and cell viability was measured via the MTT assay. None of the 13 concentrations of Namalycastis sp. crude extracts showed cytotoxicity effects on the cell types investigated. However, based on the live images captured by the IncuCyte™ imaging system, the cells treated with Namalycastis sp. crude extracts showed an increased proliferation and growth rate in less than 10 h Furthermore, the extract concentration of 8 µg/mL induced the highest cell proliferation rate whereas 8 mg/mL led to the lowest cell proliferation rate following the treatment. Overall, Namalycastis sp. crude extracts were non-toxic on mice and human cells within the tested concentrations set. Still, it increased cell viability and proliferation compared with the control. This finding could pave the way for an alternative therapeutic strategy to treat debilitating disorders such as ageing, cardiovascular diseases, and neurodegenerative diseases.
Fulltext A case of trauma related Acanthamoeba keratitis

Kamel AG, Faridah H, Yusof S, Norazah A, Nakisah MA

Trop Biomed, 2004 Dec;21(2):135-8.
PMID: 16493405 MyJurnal

Acanthamoeba is an uncommon cause of keratitis but one of the most severe because of the prolonged and painful course of the disease and poor visual outcome. Although contact lens use is the principal risk factor, about 10% of cases occur following trauma and exposure to contaminated soil or water. Two cases of Acanthamoeba keratitis involving women contact lens wearers have previously been reported in Malaysia but this is the first time, a non contact lens related Acanthamoeba keratitis is reported. The case involved a 28 year old Indonesian male construction worker who had a trauma of the right eye during work. His eye was struck by sand and dust particles after which he quickly washed with water from an open tank at the construction site. He experienced pain, redness, glaring and blurring of vision of the right eye three days later. The diagnosis was missed at initial presentation but culture of the corneal scraping had proven Acanthamoeba as the aetiological agent. The history and clinical findings of this trauma related Acanthamoeba keratitis are briefly discussed.
A method based on impedance spectroscopy to determine transport properties of polymer electrolytes

Arof AK, Amirudin S, Yusof SZ, Noor IM

Phys Chem Chem Phys, 2014 Feb 7;16(5):1856-67.
PMID: 24326909 DOI: 10.1039/c3cp53830c

In this work, we introduce a method based on impedance spectroscopy and the equations developed to evaluate, with a good degree of accuracy, the number density, mobility and diffusion coefficient of mobile ions. Nyquist plots of electrolytes based on poly(acrylonitrile) or PAN and methyl cellulose (MC) incorporated with lithium bis(oxalato)borate have been established from impedance measurements. Equivalent circuits based on a resistor and "leaky capacitor(s)" have been determined and the relevant impedance equations derived. The values of the parameters required in the equation are obtained from the Nyquist plots and the parameters that cannot be obtained from the respective plots have been obtained by trial and error in order to fit the Nyquist plots. The transport parameters are calculated using the developed equations and the results have been compared with those obtained from the broadband dielectric response (BDR) method. Finally, Fourier transform infrared (FTIR) spectroscopy has been used to verify the results obtained from the two approaches at room and elevated temperatures.
Fulltext Isolation of Acanthamoeba sp. from conjunctival sac of healthy individuals using swab

Anisah N, Amal H, Kamel AG, Yusof S, Noraina AR, Norhayati M

Trop Biomed, 2005 Jun;22(1):11-4.
PMID: 16880749 MyJurnal

Is Acanthamoeba sp. normally found in the eyes? A study was carried out to establish the possibility of Acanthamoeba sp. as a part of the normal conjunctival flora. Conjunctiva swabbing were carried out in 286 healthy Orang Asli school children using sterile cotton swab. The swab was then inoculated onto non-nutrient agar (NN-A). Heat killed Escherichia coli that was used as food source for the growth of the amoebae was pipetted onto and away from the smear. The plates were incubated at 30 degrees C and examined daily using an inverted microscope for 14 days. Morphology of the trophozoites and cysts of the amoebae were used as the taxonomic criteria for identification. Positive-controls and negative-controls were done to check for the consistency of the technique used and monitoring of contamination respectively. None of the conjunctiva swab cultured was positive for Acanthamoeba sp. This finding may indicate that Acanthamoeba sp. is not part of normal conjunctival flora or conjunctiva swab is an insensitive technique to isolate the organism. However, a more extensive research is needed to investigate these possibilities.
Effect of maturity on chlorophyll, tannin, color, and polyphenol oxidase (PPO) activity of sugarcane juice (Saccharum officinarum Var. Yellow Cane)

Qudsieh HY, Yusof S, Osman A, Rahman RA

J Agric Food Chem, 2002 Mar 13;50(6):1615-8.
PMID: 11879045

A study was conducted to determine the effect of sugarcane maturation on the contents of chlorophyll, tannin, and polyphenol oxidase (PPO) activity and on color change of sugarcane juice. The maturation period of the cane studied was between 3 and 10 months after planting. Different parts of the cane, namely, the top, middle, and bottom portions, were analyzed. Results obtained indicated that there were significant (P < 0.01) decreases in total chlorophyll a and b and tannin contents during maturity followed by slower rates of decrease of both parameters at the end of maturity stages. There were no significant differences (P > 0.05) in chlorophyll and tannin contents between the middle and bottom portions. On the other hand, the top portion of the stem had a significantly (P < 0.01) lower concentration of chlorophyll and a significantly (P < 0.01) higher content of tannin. PPO activity of sugarcane juice was determined using chlorogenic acid as a substrate. There was a highly significant difference (P < 0.01) in PPO activity of cane juice during maturity. PPO activity was high at the early development stage, decreased during maturation, and then remained relatively constant at the end of maturity. PPO activity was higher when chlorogenic acid was used as substrate. There were also significant differences (P < 0.01) in juice color (L*, a*, b* values) from different portions at different maturity stages. At the early stages, the color of extracted juice was dark, and then the juice turned to yellowish green during maturity. The decrease in green color or the increase in the yellow color could be associated with the decline in chlorophyll. The overall color change (DeltaE) at maturity indicated that the color of the middle and bottom portions was lower than that of the top portion.
Potential immunosuppressive and antiinflammatory activities of Malaysian medicinal plants characterized by reduced cell surface expression of cell adhesion molecules

Tanaka S, Yoichi S, Ao L, Matumoto M, Morimoto K, Akimoto N, et al.

Phytother Res, 2001 Dec;15(8):681-6.
PMID: 11746860

In the search for agents effective against immune-mediated disorders and inflammation, we have screened Malaysian medicinal plants for the ability to inhibit the expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) on the surface of murine endothelial cells (F-2), and mouse myeloid leukaemia cells (M1), respectively. Of 41 kinds (29 species, 24 genera, 16 families) of Malaysian plants tested, 10 and 19 plant samples significantly downregulated the expression of ICAM-1 and VCAM-1, respectively. Bioassay-directed fractionation of an extract prepared from the bark of Goniothalamus andersonii showed that its ingredients, goniothalamin (1) and goniodiol (2) inhibited the cell surface expression of both ICAM-1 and VCAM-1. The present results suggest that Malaysian medicinal plants may be abundant natural resources for immunosuppressive and antiinflammatory substances.

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