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Fulltext Ophiocordyceps sinensis: a prominent source of bioactive components for alleviating overactive bladder

Li-Yin Pang, Chon-Seng Tan, Szu-Ting Ng, Kuan-Hon Lim, Sue-Mian Then, Ting Kang Nee

Life Sciences, Medicine and Biomedicine, 2020;4(1):0-0.
MyJurnal

Ophiocordyceps sinensis is one of the most sought-after medicinal fungi used to treat various medical conditions such as respiratory diseases, liver and kidney dysfunctions. In China, it is widely used for alleviation of frequent urination where patients treated with O. sinensis have shown improvement in nocturia, which is the most common symptom of overactive bladder (OAB). Many studies have reported its anticancer, anti-inflammatory, anti-oxidative, hypoglycaemic and vasorelaxation properties. These properties are attributable to the presence of bioactive components such as polysaccharides, proteins and nucleosides. This mini-review highlights the medicinal potential of O. sinensis in alleviating OAB, which is a debilitating condition with a profound impact on the quality of life in a high proportion of older people. Four possible mechanisms of action of O. sinensis are suggested. Firstly, the relaxation of bladder smooth muscle through calcium dynamic, production of nitric acid (NO) and adenosine triphosphate (ATP). A second mechanism proposed is through the suppression of micturition reflex. The unequivocal properties of O. sinensis as anti-inflammatory and anti-oxidant, are two other plausible explanations, as both chronic inflammation and accumulation of oxidative stress molecules are associated with OAB exacerbation. With the recent success in cultivation of O. sinensis and the positive results from toxicity studies, a better understanding of its pharmacological actions can be further substantiated, including its use for relieving OAB.
Fulltext Awareness, knowledge & attitude on urinary tract infection among government secondary school students in Shah Alam, Malaysia

Neni Widiasmoro Selamat, Kenneth Paul Martinez, Mohammad Sarimie Nurul Nizam, Gaiyathre Subrain, Eva Tan Lee Yin, Titinun Auamnoy

Malaysian Journal of Medicine and Health Sciences, 2020;16(101):51-57.
MyJurnal

Introduction: A cross-sectional study was conducted to provide preliminary insight of Awareness, Knowledge and Attitude (AKA) assessment on urinary tract infection (UTI) among adolescents which includes the general level of AKA and correlation between the domains as well as the relationship between Total AKA and the sociodemographic factors. Methods: A modified and adapted questionnaire was developed, consisting of socio-demographic questions and AKA domains employing descriptive statistics, linear regression and multiple regression analysis via SPSS Ver- sion 23.0. Results: In general, AKA level was reported as moderate (0.5 ± 0.11). Among the three domains, Knowl- edge (0.70 ± 0.12) risen with the most astounding mean, took after Awareness (0.36 ± 0.22) and Attitude (0.65 ± 0.11). A positive but weak correlation was found between the domains; Awareness and Knowledge is significant at p = 0.034, r = 0.157; R2 = 0.02 and similarly, a weak correlation was also found between Knowledge and Attitude which is significant at p = 0.000, r = 0.411; R2 = 0.17. After covariates adjustment, female gender was found to have the strongest relationship with Total AKA. Conclusion: The general level of Total AKA on UTI is moderate. The AKA domains in this study was found to be positively correlated and female was found to be the best predictor for a better Total AKA on UTI. Thus, these findings provide important information to formulate an effective education interven- tion to improve the AKA on UTI among adolescents.
Fulltext CYTOCHROME OXIDASE I (COI) DIVERGENCE ASSESSMENT OF FAMILY NEMIPTERIDAE FROM MALAYSIAN WATERS

LIEW YOU EN, SALWANI ABDULLAH, TAN MIN PAU, MAZLAN ABD GHAFFAR, ALIAS MAN, TUN NURUL AIMI MAT JAAFAR

UMT Journal of Undergraduate Research, 2019;1(1):41-48.
MyJurnal

DNA Barcoding, primarily focusing on cytochrome coxidase subunit I (COI) gene has been appraised as an effective tool for species identification. Nonetheless, species identification based on molecular approach is essential for discrimination of look-alike species. In this study, we focused on the marine fishes Family Nemipteridae, one of the commercially important group distributed within the surrounding seas of Malaysia. Some of the samples were collected during the National Demersal Trawl Survey in the Exclusive Economic Zone of East Coast Peninsular Malaysia by the Department of Fishery Malaysia. A 652bp region of COI was sequenced for 74 individuals from nine putative species. Additional 34 COIsequences from GenBank were also included in this study making the total number of samples analysed to 108 individuals. The averageKimura 2-parameter (K2P) nucleotide divergence was 0.34% among individuals within species and 6.97% within genera. All putative species formed monophyletic clades in both Neighbour-joining (NJ) and Maximum-likelihood (ML) trees. However, there was a potential misidentification in specimen identified as Nemipterus tambuloides,as the specimen did not group with their own taxa. It was genetically grouped in Nemipterus thosaporni clade. This study supports the effectiveness of COIgene in species discrimination of Family Nemipteridae.
Fulltext Knowledge and attitude towards vaccine preventable diseases and vaccination among prospective Malaysian Hajj Pilgrims in Klang Valley, Malaysia

Zhi Han Tan, Fatin Nor Aisyah Mohammed Zamli, Lukman Hariz Mohd Izal, Narcisse Joseph, Nurul Azmawati Mohamed, Syafinaz Amin Nordin

Malaysian Journal of Medicine and Health Sciences, 2020;16(201):2-8.
MyJurnal

Introduction: Hajj is a unique religious mass gathering among Muslims hosted by Kingdom of Saudi Arabia (KSA) annually. It is a fifth pillar that is compulsory to be carried among muslim. Infections due to Neisseria meningitidis, Streptococcus Pneumoniae and Influenza virus are very high among Hajj pilgrims in KSA. Study shows knowledge and attitude towards vaccine preventable disease and vaccination which is very important for the prevention of these infectious diseases. This study aims to determine knowledge and attitude among the prospective Malaysian hajj pilgrims on vaccine preventable disease and vaccination. Method: A cross sectional study was conducted among prospective hajj pilgrims in June 2019. Self-administered questionnaires were given to the respondents through simple random sampling. The socio-demographic characteristics were described using descriptive analysis. Chi-square test was used to analyse the association between the socio-demographic and Malaysian hajj pilgrims’ knowledge and attitude towards the vaccine preventable diseases and vaccination. Results: A total of 135 respondents were recruited in the study. There were statistically significant associations between the knowledge and the highest education level (p=0.01), and also between the knowledge and the occupation (p=0.02) on vaccine preventable disease and vaccination. Conclusion: There is a lack of knowledge among the Malaysian hajj pilgrims about these vaccine preventable diseases and vaccination, especially those who have lower education level and also unemployed. Tabung Haji are highly advised to focus on these group and prepare a special course that focused on these vaccine preventable diseases so that Malaysian Hajj pilgrims will be protected.
Fulltext Detection of Entamoeba histolytica in experimentally induced amoebic liver abscess: comparison of three staining methods

Ning TZ, Kin WW, Mustafa S, Ahmed A, Noordin R, Cheong TG, et al.

Asian Pac J Trop Biomed, 2012 Jan;2(1):61-5.
PMID: 23569836 DOI: 10.1016/S2221-1691(11)60191-3

To compare the efficacy of three different tissue stains, namely haematoxylin and eosin (H&E), periodic-acid Schiff (PAS) and immunohistochemical (IHC) stains for detection of Entamoeba histolytica (E. histolytica) trophozoites in abscessed liver tissues of hamster.
Survival of beneficial microbes in liquid bioformulation and optimization of different carrier materials using RSM technique

Chompa SS, Zuan ATK, Amin AM, Hun TG, Ghazali AHA, Sadeq BM, et al.

Int Microbiol, 2023 Aug 31.
PMID: 37651053 DOI: 10.1007/s10123-023-00423-4

Soil salinity in rice cultivation areas is considered a severely limiting factor that adversely affects the quantity and quality of rice production in wetlands. Recently, the alternative use of salt-tolerant plant growth-promoting rhizobacteria (PGPR) inhabiting extreme saline conditions has gained remarkable attention and had positive effects on soil and crops. Therefore, a study has been initiated to develop a liquid biofertilizer formulation from locally isolated multi-strain salt-tolerant PGPR strains such as Bacillus tequilensis and Bacillus aryabhattai, using glycerol (5 mM), trehalose (10 mM), and polyvinylpyrrolidone (PVP) at 1% as additives to prolong the shelf-life of the bacteria. After 3 months of incubation, the bacterial population in the trehalose-supplemented mixed strain was highest at 9.73×107 CFU/mL, followed by UPMRE6 and UPMRB9 at 9.40×107 CFU/mL and 8.50×107 CFU/mL respectively. The results showed that the optimal trehalose concentration successfully prolonged the shelf-life of bacteria with minimal cell loss. Validation of quadratic optimization by response surface methodology revealed that the cell density of the mixed strain was 4.278×107 log CFU/mL after 24 h. The precision ratio was 99.7% higher than the predicted value in the minimized medium formulation: 0.267 g/mL trehalose, 1% glycerol, at 120 rpm agitation using the data analysis tools of Design Expert software. The population study confirmed the better and longer survival of salt-tolerant PGPR fortified with 10 mM trehalose, which was considered the best liquid biofertilizer formulation. Moreover, the optimized trehalose-glycerol liquid formulation can be used commercially as it is cost-effective.
Silencing of novel TtVtg6-like induced ovarian cell apoptosis in ancient chelicerate Tachypleus tridentatus

Tan K, Waiho K, Tan K, Qiao Y, Lim LS, Yang X, et al.

Biochem Biophys Res Commun, 2023 Oct 30;679:66-74.
PMID: 37673004 DOI: 10.1016/j.bbrc.2023.08.066

Vitellogenin (Vtg) serves as the precursor of yolk protein and exhibits widespread distribution in tissues, including in the ovary of both vertebrates and invertebrates. Vtg plays a critical role in facilitating oocyte maturation and embryonic development following oviposition. In this study, we have successfully elucidated the complete transcript sequence of TtVtg6-like from an ancient chelicerate Tachypleus tridentatus. The TtVtg6-like transcript encompassed a length of 4887 bp and encoded 1629 amino acids residues. Notably, TtVtg6-like was found to contain 25 exons. Furthermore, the molecular weight and isoelectric point of TtVtg6-like were determined to be 191.6 KDa and 6.73, respectively. Subsequent mRNA expression analysis demonstrated the specific expression of TtVtg6-like in ovary and yellow connective tissue. In addition, TtVtg6-like was located and distributed in both ovary and yellow connective tissue. Intriguingly, employing an siRNA approach to silence TtVtg6-like resulted in a decrease in TtVtg6-like transcription levels. Concomitantly, TtVtg6-like silencing led to increase production of ROS, ultimately resulting in DNA damage and cell apoptosis within the ovarian primary cell. The induction of apoptosis ovarian primary cells due to TtVtg6-like silencing was further corroborated through TUNEL assay and flow cytometry analysis. Overall, our findings underscore the significance of TtVtg6-like in ovarian cell development, revealing its potential association with ovarian cell apoptosis. Consequently, the insights gained from this study contribute to the future exploration of vitellogenesis and ovarian development in T. tridentatus.
Growth and protein response of rice plant with plant growth-promoting rhizobacteria inoculations under salt stress conditions

Chompa SS, Zuan ATK, Amin AM, Hun TG, Ghazali AHA, Sadeq BM, et al.

Int Microbiol, 2024 Jan 03.
PMID: 38172302 DOI: 10.1007/s10123-023-00469-4

Soil salinity has been one of the significant barriers to improving rice production and quality. According to reports, Bacillus spp. can be utilized to boost plant development in saline soil, although the molecular mechanisms behind the interaction of microbes towards salt stress are not fully known. Variations in rice plant protein expression in response to salt stress and plant growth-promoting rhizobacteria (PGPR) inoculations were investigated using a proteomic method and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Findings revealed that 54 salt-responsive proteins were identified by mass spectrometry analysis (LC-MS/MS) with the Bacillus spp. interaction, and the proteins were functionally classified as gene ontology. The initial study showed that all proteins were labeled by mass spectrometry analysis (LC-MS/MS) with Bacillus spp. interaction; the proteins were functionally classified into six groups. Approximately 18 identified proteins (up-regulated, 13; down-regulated, 5) were involved in the photosynthetic process. An increase in the expression of eight up-regulated and two down-regulated proteins in protein synthesis known as chaperones, such as the 60 kDa chaperonin, the 70 kDa heat shock protein BIP, and calreticulin, was involved in rice plant stress tolerance. Several proteins involved in protein metabolism and signaling pathways also experienced significant changes in their expression. The results revealed that phytohormones regulated the manifestation of various chaperones and protein abundance and that protein synthesis played a significant role in regulating salt stress. This study also described how chaperones regulate rice salt stress, their different subcellular localizations, and the activity of chaperones.
Fulltext Treatment outcomes of sofosbuvir/velpatasvir/voxilaprevir among NS5A inhibitor-experienced patients with hepatitis C: Real-world data from a multicenter Asian registry

Wong YJ, Kumar R, Kumar R, Tan J, Liu CH, Hui VK, et al.

J Gastroenterol Hepatol, 2022 Aug;37(8):1642-1644.
PMID: 35723645 DOI: 10.1111/jgh.15918
Fulltext Utilization of acid pre-treated coconut dregs as a substrate for production of detergent compatible lipase by Bacillus stratosphericus

Mohd Zin NB, Mohamad Yusof B, Oslan SN, Wasoh H, Tan JS, Ariff AB, et al.

AMB Express, 2017 Dec;7(1):131.
PMID: 28651380 DOI: 10.1186/s13568-017-0433-y

In recent years, many efforts have been directed to explore the methods to reduce the production costs of industrial lipase by improving the yield and the use of low-cost agricultural wastes. Coconut dregs, which is a lignocellulosic by-product from coconut oil and milk processing plants, is rich in cellulose (36%) and crude fat (9%). A newly isolated Bacillus stratosphericus has been demonstrated to perform cellulose hydrolysis on coconut dregs producing fermentable sugars. The highest extracellular lipase activity of 140 U/mL has been achieved in submerged fermentation with acid pre-treated coconut dregs. The lipase was found to be active over a wide range of temperatures and pHs. The activity of lipase can be generally increased by the presence of detergent ingredients such as Tween-80, cetyltrimethylammonium bromide, hydrogen peroxide and phosphate per sulphate. The great compatibility of lipase in commercial detergents has also underlined its potential as an additive ingredient in biodetergent formulations.
VP1 residues around the five-fold axis of enterovirus A71 mediate heparan sulfate interaction

Tan CW, Sam IC, Lee VS, Wong HV, Chan YF

Virology, 2017 01 15;501:79-87.
PMID: 27875780 DOI: 10.1016/j.virol.2016.11.009

Enterovirus A71 (EV-A71) is a neurotropic enterovirus that uses heparan sulfate as an attachment receptor. The molecular determinants of EV-A71-heparan sulfate interaction are unknown. With In silico heparin docking and mutagenesis of all possible lysine residues in VP1, we identified that K162, K242 and K244 are responsible for heparin interaction and inhibition. EV-A71 mutants with K242A and K244A rapidly acquired compensatory mutations, T100K or E98A, and Q145R-T237N respectively, which restored the heparin-binding phenotype. Both VP1-98 and VP1-145 modulates heparin binding. Heparin-binding phenotype was completely abolished with VP1-E98-E145, but was restored by an E98K or E145Q substitution. During cell culture adaptation, EV-A71 rapidly acquired K98 or Q/G145 to restore the heparin-binding phenotype. Together with next-generation sequencing analysis, our results implied that EV-A71 has high genetic plasticity by modulating positively-charged residues at the five-fold axis during in vitro heparin adaptation. Our finding has impact on EV-A71 vaccine production, evolutionary studies and pathogenesis.
Fulltext Anti-neuroinflammatory Activity of Elephantopus scaber L. via Activation of Nrf2/HO-1 Signaling and Inhibition of p38 MAPK Pathway in LPS-Induced Microglia BV-2 Cells

Chan CK, Tan LT, Andy SN, Kamarudin MNA, Goh BH, Kadir HA

Front Pharmacol, 2017;8:397.
PMID: 28680404 DOI: 10.3389/fphar.2017.00397

Elephantopus scaber L. (family: Asteraceae) has been traditionally utilized as a folkloric medicine and scientifically shown to exhibit anti-inflammatory activities in various in vivo inflammatory models. Given the lack of study on the effect of E. scaber in neuroinflammation, this study aimed to investigate the anti-neuroinflammatory effect and the underlying mechanisms of ethyl acetate fraction from the leaves of E. scaber (ESEAF) on the release of pro-inflammatory mediators in lipopolysaccharide (LPS)-induced microglia cells (BV-2). Present findings showed that ESEAF markedly attenuated the translocation of NF-κB to nucleus concomitantly with the significant mitigation on the LPS-induced production of NO, iNOS, COX-2, PGE2, IL-1β, and TNF-α. These inflammatory responses were reduced via the inhibition of p38. Besides, ESEAF was shown to possess antioxidant activities evident by the DPPH and SOD scavenging activities. The intracellular catalase enzyme activity was enhanced by ESEAF in the LPS-stimulated BV-2 cells. Furthermore, the formation of ROS induced by LPS in BV-2 cells was reduced upon the exposure to ESEAF. Intriguingly, the reduction of ROS was found in concerted with the activation of Nrf2 and HO-1. It is conceivable that the activation promotes the scavenging power of antioxidant enzymes as well as to ameliorate the inflammatory response in LPS-stimulated BV-2 cells. Finally, the safety profile analysis through oral administration of ESEAF at 2000 mg/kg did not result in any mortalities, adverse effects nor histopathologic abnormalities of organs in mice. Taken altogether, the cumulative findings suggested that ESEAF holds the potential to develop as nutraceutical for the intervention of neuroinflammatory disorders.
Overview of Signaling Mechanism Pathways Employed by BPAid in Vasodilatory Activity

Loh YC, Tan CS, Ch'ng YS, Ahmad M, Ng CH, Yam MF

J Med Food, 2017 Dec;20(12):1201-1213.
PMID: 28953423 DOI: 10.1089/jmf.2017.3958

Hypertension, one of the famous "silent killers" that can attack people at any age, is a current hot topic among scientists due to multiple syndromic behavior and concomitant diseases. The new scientific-based Traditional Chinese Medicine (TCM) formulation approach was used in a previous study by combining five TCM herbs, including Gastrodia elata Bl., Uncaria rhynchophylla (Miq.) Miq. ex Havil., Pueraria thomsonii Benth., Panax notoginseng (Burk.) F.H. Chen, and Alisma orientalis (Sam.) Juzep in optimized ratio (named BPAid). The objective of the present study was to evaluate the mechanism pathways employed by BPAid for vasodilatory effect with the use of an in vitro isolated aortic rings assay. Interestingly, all the mechanisms investigated were involved in the BPAid's vasodilation activity in which the majority contributed through the nitric oxide/soluble guanylyl cyclase/cyclic guanosine monophosphate (NO/sGC/cGMP) pathways, followed by prostacyclin (PGI2), β2-adrenergic, and M3-receptors pathways. Furthermore, the BPAid appeared to manage vascular tone by regulating action potential through potassium and both voltage-operated calcium channel and inositol triphosphate receptor (IP3R) pathways. The results obtained has confirmed the expected outcome that the benefits of TCM herbs in BPAid can meet the criteria of counteracting multiple signaling mechanism pathways involved in the etiology of hypertension. In addition to this study, the fingerprints and chemical properties of BPAid was identified by using tri-step Fourier transform infrared spectroscopy and compared with its derivatives. The results obtained suggested that the majority of the vasodilatory effects exerted by BPAid were attributed to the presence of saponins and aromatic ring-containing vasoactive compounds.
Fulltext Properties of Foamed Mortar Prepared with Granulated Blast-Furnace Slag

Zhao X, Lim SK, Tan CS, Li B, Ling TC, Huang R, et al.

Materials (Basel), 2015 Jan 30;8(2):462-473.
PMID: 28787950 DOI: 10.3390/ma8020462

Foamed mortar with a density of 1300 kg/m³ was prepared. In the initial laboratory trials, water-to-cement (w/c) ratios ranging from 0.54 to 0.64 were tested to determine the optimal value for foamed mortar corresponding to the highest compressive strength without compromising its fresh state properties. With the obtained optimal w/c ratio of 0.56, two types of foamed mortar were prepared, namely cement-foamed mortar (CFM) and slag-foamed mortar (SFM, 50% cement was replaced by slag weight). Four different curing conditions were adopted for both types of foamed mortar to assess their compressive strength, ultrasonic pulse velocity (UPV) and thermal insulation performance. The test results indicated that utilizing 50% of slag as cement replacement in the production of foamed mortar improved the compressive strength, UPV and thermal insulation properties. Additionally, the initial water curing of seven days gained higher compressive strength and increased UPV values as compared to the air cured and natural weather curing samples. However, this positive effect was more pronounced in the case of compressive strength than in the UPV and thermal conductivity of foamed mortar.
Fulltext Surface Characteristics and Catalytic Activity of Copper Deposited Porous Silicon Powder

Halim MYA, Tan WL, Bakar NHHA, Bakar MA

Materials (Basel), 2014 Dec 04;7(12):7737-7751.
PMID: 28788272 DOI: 10.3390/ma7127737

Porous structured silicon or porous silicon (PS) powder was prepared by chemical etching of silicon powder in an etchant solution of HF: HNO₃: H₂O (1:3:5 v/v). An immersion time of 4 min was sufficient for depositing Cu metal from an aqueous solution of CuSO₄ in the presence of HF. Scanning electron microscopy (SEM) analysis revealed that the Cu particles aggregated upon an increase in metal content from 3.3 wt% to 9.8 wt%. H₂-temperature programmed reduction (H₂-TPR) profiles reveal that re-oxidation of the Cu particles occurs after deposition. Furthermore, the profiles denote the existence of various sizes of Cu metal on the PS. The Cu-PS powders show excellent catalytic reduction on the p-nitrophenol regardless of the Cu loadings.
Dilute sulfuric acid hydrolysis of red macroalgae Eucheuma denticulatum with microwave-assisted heating for biochar production and sugar recovery

Teh YY, Lee KT, Chen WH, Lin SC, Sheen HK, Tan IS

Bioresour Technol, 2017 Dec;246:20-27.
PMID: 28781203 DOI: 10.1016/j.biortech.2017.07.101

This study aims to produce biochar and sugars from a macroalga Eucheuma denticulatum using dilute sulfuric acid hydrolysis along with microwave-assisted heating. The reactions were operated at sulfuric acid concentrations of 0.1 and 0.2M, reaction temperatures of 150-170°C and a heating time of 10min. Compared to the raw macroalga, biochar qualities were improved with increased carbon content and lower ash and moisture contents. The calorific value of the biochar could be intensified up to 45%, and 39% of energy yield was recovered. Apart from producing biochar, the highest total reducing sugars were 51.47g/L (74.84% yield) along with a low by-product 5-HMF of 0.20g/L, when the biomass was treated under the optimum conditions at 160°C with 0.1M H2SO4. Thus, this study demonstrated that macroalgae could be potentially used as biomass feedstock under microwave-assisted acid hydrolysis for the production of biofuel and value-added products.
Fulltext Fabrication and Compressive Properties of Low to Medium Porosity Closed-Cell Porous Aluminum Using PMMA Space Holder Technique

Jamal NA, Tan AW, Yusof F, Katsuyoshi K, Hisashi I, Singh S, et al.

Materials (Basel), 2016 Mar 30;9(4).
PMID: 28773377 DOI: 10.3390/ma9040254

In recent years, closed-cell porous Aluminum (Al) has drawn increasing attention, particularly in the applications requiring reduced weight and energy absorption capability such as in the automotive and aerospace industries. In the present work, porous Al with closed-cell structure was successfully fabricated by powder metallurgy technique using PMMA as a space holder. The effects of the amount of PMMA powder on the porosity, density, microstructure and compressive behaviors of the porous specimens were systematically evaluated. The results showed that closed-cell porous Al having different porosities (12%-32%) and densities (1.6478 g/cm³, 1.5125 g/cm³ and 1.305 g/cm³) could be produced by varying the amount of PMMA (20-30 wt %). Meanwhile, the compressive behavior results demonstrated that the plateau stress decreased and the energy absorption capacity increased with increasing amount of PMMA. However, the maximum energy absorption capacity was achieved in the closed-cell porous Al with the addition of 25 wt % PMMA. Therefore, fabrication of closed-cell porous Al using 25 wt % PMMA is considered as the optimal condition in the present study since the resultant closed-cell porous Al possessed good combinations of porosity, density and plateau stress, as well as energy absorption capacity.
Fulltext Added Value of Digital Breast Tomosynthesis Combined with Digital Mammography According to Reader Agreement: Changes in BI-RADS Rate and Follow-Up Management

Galati F, Marzocca F, Bassetti E, Luciani ML, Tan S, Catalano C, et al.

Breast care (Basel, Switzerland), 2017 Sep;12(4):218-222.
PMID: 29070984 DOI: 10.1159/000477537

BACKGROUND: The aim of this study was to evaluate the added value of digital breast tomosynthesis (DBT) when combined with digital mammography (DM) in BI-RADS assessment and follow-up management.
METHODS: From February 2014 to January 2015, 214 patients underwent DM and DBT, acquired with a Siemens Mammomat Inspiration unit. 2 expert readers independently reviewed the studies in 2 steps: DM and DM+DBT, according to BI-RADS rate. Patients with BI-RADS 0, 3, 4, and 5 were recalled for work-up. Inter-reader agreement for BI-RADS rate and work-up rate were evaluated using Cohen's kappa.
RESULTS: Inter-reader agreement (κ value) for BI-RADS classification was 0.58 for DM and 0.8 for DM+DBT. DM+DBT increased the number of BI-RADS 1, 2, 4, 5 and reduced the number of BI-RADS 0 and 3 for both readers compared to DM alone. Regarding work-up rate agreement, κ was poor for DM and substantial (0.7) for DM+DBT. DM+DBT also reduced the work-up rate for both Reader 1 and Reader 2.
CONCLUSION: DM+DBT increased the number of negative and benign cases (BI-RADS 1 and 2) and suspicious and malignant cases (BI-RADS 4 and 5), while it reduced the number of BI-RADS 0 and 3. DM+DBT also improved inter-reader agreement and reduced the overall recall for additional imaging or short-interval follow-up.
LAT is essential for the mast cell stabilising effect of tHGA in IgE-mediated mast cell activation

Tan JW, Israf DA, Md Hashim NF, Cheah YK, Harith HH, Shaari K, et al.

Biochem Pharmacol, 2017 Nov 15;144:132-148.
PMID: 28813645 DOI: 10.1016/j.bcp.2017.08.010

Mast cells play a central role in the pathogenesis of allergic reaction. Activation of mast cells by antigens is strictly dependent on the influx of extracellular calcium that involves a complex interaction between signalling molecules located within the cells. We have previously reported that tHGA, an active compound originally isolated from a local shrub known as Melicope ptelefolia, prevented IgE-mediated mast cell activation and passive systemic anaphylaxis by suppressing the release of interleukin-4 (IL-4) and tumour necrosis factor (TNF)-α from activated rat basophilic leukaemia (RBL)-2H3 cells. However, the mechanism of action (MOA) as well as the molecular target underlying the mast cell stabilising effect of tHGA has not been previously investigated. In this study, DNP-IgE-sensitised RBL-2H3 cells were pre-treated with tHGA before challenged with DNP-BSA. To dissect the MOA of tHGA in IgE-mediated mast cell activation, the effect of tHGA on the transcription of IL-4 and TNF-α mRNA was determined using Real Time-Polymerase Chain Reaction (qPCR) followed by Calcium Influx Assay to confirm the involvement of calcium in the activation of mast cells. The protein lysates were analysed by using Western Blot to determine the effect of tHGA on various important signalling molecules in the LAT-PLCγ-MAPK and PI3K-NFκB pathways. In order to identify the molecular target of tHGA in IgE-mediated mast cell activation, the LAT and LAT2 genes in RBL-2H3 cells were knocked-down by using RNA interference to establish a LAT/LAT2 competition model. The results showed that tHGA inhibited the transcription of IL-4 and TNF-α as a result of the suppression of calcium influx in activated RBL-2H3 cells. The results from Western Blot revealed that tHGA primarily inhibited the LAT-PLCγ-MAPK pathway with partial inhibition on the PI3K-p65 pathway without affecting Syk. The results from RNAi further demonstrated that tHGA failed to inhibit the release of mediators associated with mast cell degranulation under the LAT/LAT2 competition model in the absence of LAT. Collectively, this study concluded that the molecular target of tHGA could be LAT and may provide a basis for the development of a mast cell stabiliser which targets LAT.
Stigmasterol: An adjuvant for beta lactam antibiotics against beta-lactamase positive clinical isolates

Yenn TW, Arslan Khan M, Amiera Syuhada N, Chean Ring L, Ibrahim D, Tan WN

Steroids, 2017 Dec;128:68-71.
PMID: 29104098 DOI: 10.1016/j.steroids.2017.10.016

The emergence of beta lactamase producing bacterial strains eliminated the use of beta lactam antibiotics as chemotherapeutic alternative. Beta lactam antibiotics can be coupled with non-antibiotic adjuvants to combat these multidrug resistant strains. We study the synergistic antibiotic effect of stigmasterol as adjuvant of ampicillin against clinical isolates. Ampicillin was used in this study as a beta lactam antibiotic model. All test bacteria were beta lactamase producing clinical isolates. The combination showed significantly better antibiotic activity on all bacteria tested. The two test substances have synergistic antibiotic activity, and the effect was observed in both Gram positive and Gram negative bacteria. The synergistic antibiotic effect of stigmasterol and ampicillin was evident by the low fractional inhibitory concentration (FIC) index on Checkerboard Assay. The results suggest that the combination of ampicillin and stigmasterol acts additively in the treatment of infections caused by beta-lactamase producing pathogens. In bacterial growth reduction assay, ampicillin and stigmasterol alone exhibited very weak inhibitory effect on the bacterial growth, relative to ethanol control. Comparatively, combination of stigmasterol-ampicillin greatly reduced the colony counts at least by 98.7%. In conclusion, we found synergistic effects of stigmasterol and ampicillin against beta lactamase producing clinical isolates. This finding is important as it shows potential application of stigmasterol as an antibiotic adjuvant.

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