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Characterization of phenolic compounds, carotenoids, vitamins and antioxidant activities of selected Malaysian wild edible plants

Wong JY, Matanjun P, Ooi YB, Chia KF

Int J Food Sci Nutr, 2013 Aug;64(5):621-31.
PMID: 23368987 DOI: 10.3109/09637486.2013.763910

This study was carried out to characterize phenolic compounds, carotenoids, vitamins and the antioxidant activity of selected wild edible plants. Plant extracts were purified, and phenolic compounds comprising 11 phenolic acids (hydroxybenzoic acid and hydrocinnamic acid) and 33 flavonoids (including catechin, glycosides and aglycones) were analysed using High Performance Liquid Chromatography - Diode Array Detector (HPLC-DAD). Furthermore, the contents of ascorbic acid and tocopherol ((α and γ tocopherol) and carotenoids (lutein and β-carotene) were also determined. The major phenolics identified consisted of glycosides of flavones (apigenin and luteolin) and flavonols (kaempferol and quercetin). Among the phenolic acids identified after hydrolysis, coumaric acid was the predominant phenolic acid in all the extracts of wild plants. Ascorbic acid [53.8 mg/100 g fresh weight (FW)] and β-carotene (656.5 mg/100 g FW) showed the highest content in the leaf of Heckeria umbellatum. In conclusion, the leaves of H. umbellatum, Aniseia martinicensis and Gonostegia hirta have excellent potential in the future to emerge as functional ingredients.
Glutathione S transferase-theta (GSTT1) genetic polymorphism among Chinese, Malays and Indians in Singapore

Lee EJ, Wong JY, Yeoh PN, Gong NH

Pharmacogenetics, 1995 Oct;5(5):332-4.
PMID: 8563775

Glutathione S-transferase-theta (GSTT1) is subject to a genetic polymorphism where approximately 50% of a Caucasian population are homozygous for the null allele. Because of the possible association of the polymorphism with increased cancer risk in individuals, we genotyped by polymerase chain reaction 187 normal Chinese, 167 normal Malays and 152 normal Indians from Singapore and Malaysia. The proportion of Chinese, Malays and Indians with the null genotype were 58%, 38% and 16% respectively and mirrored previously reported frequencies of the GSTM1 null genotype in these populations. The frequency of the combined GSTM1 and GSTT1 null genotypes among Chinese, Malays and Indians were 37%, 22% and 5% respectively. The similarity with predicted frequencies indicated no interaction between the two genetic polymorphisms.
Frequency of mutant CYP1A1, NAT2 and GSTM1 alleles in normal Indians and Malays

Zhao B, Lee EJ, Wong JY, Yeoh PN, Gong NH

Pharmacogenetics, 1995 Oct;5(5):275-80.
PMID: 8563767

Several xenobiotic metabolizing enzymes, including CYP1A1, NAT2 and GSTM1, are subject to genetic polymorphisms. Because these enzymes are important for the detoxification and/or bioactivation of drugs and carcinogens, these polymorphisms have important implications in therapeutics and cancer susceptibility. The distributions of CYP1A1, NAT2 and GSTM1 genotype frequencies in unrelated individuals of the Indian (n = 139) and Malay (n = 146) populations were characterized by the polymerase chain reaction. The respective allelic frequencies of wild-type and mutant alleles of CYP1A1 were 0.82 and 0.18 for the Indians, and 0.69 and 0.31 for the Malays. The frequencies of wild-type, M1, M2 and M3 of NAT2 among Indians were 0.44, 0.20, 0.32 and 0.04 respectively. The corresponding NAT2 allelic frequencies in Malays were 0.41, 0.12, 0.38 and 0.09. The GSTM1*A allele could not be amplified in 33.1% of Indians and 61.6% of Malays. At least one GSTM1*B allele was detected in 7.2% and 7.5% of the respective populations. The allelic frequencies of CYP1A1, NAT2 and GSTM1 among Malays are similar to previously reported frequencies among Chinese in the region. These findings will be of importance in the determination of cancer risks in these populations.
Efficacy and safety of dihydroartemisinin-piperaquine for treatment of uncomplicated Plasmodium falciparum malaria in endemic countries: meta-analysis of randomised controlled studies

Naing C, Mak JW, Aung K, Wong JY

Trans R Soc Trop Med Hyg, 2013 Feb;107(2):65-73.
PMID: 23222952 DOI: 10.1093/trstmh/trs019

The present review aimed to synthesise available evidence on the efficacy of dihydroartemisinin-piperaquine (DP) in treating uncomplicated Plasmodium falciparum malaria in people living in malaria-endemic countries by performing a meta-analysis of relevant studies. We searched relevant studies in electronic data bases up to December 2011. Published results from randomised controlled trials (RCTs) comparing efficacy of DP with other artemisinin-based combination therapies (ACTs), or non-ACTs, or placebo were selected. The primary endpoint was 28-day and 42-day treatment failure. We identified 26 RCTs. Many of the studies included in the present review were of high quality. Overall, DP, artesunate-mefloquine (MAS3) and artemether-lumefentrine (AL) were equally effective for reducing the risk of recurrent parasitaemia. The PCR confirmed efficacy of DP (99.5%) and MAS3 (97.7%) at day 28 exceeded 90%; both are efficacious. Comparable efficacy was also found for DP (95.6%) and AL (94.3%). The present review has documented that DP is comparable to other currently used ACTs such as MAS3 and AL in treating uncomplicated falciparum malaria. The better safety profile of DP and once-daily dosage improves adherence and its fixed co-formulation ensures that both drugs are taken together. Our conclusion is that DP has the potential to become a first-line antimalarial drug.
Automated otolith image classification with multiple views: an evaluation on Sciaenidae

Wong JY, Chu C, Chong VC, Dhillon SK, Loh KH

J Fish Biol, 2016 Aug;89(2):1324-44.
PMID: 27364089 DOI: 10.1111/jfb.13039

Combined multiple 2D views (proximal, anterior and ventral aspects) of the sagittal otolith are proposed here as a method to capture shape information for fish classification. Classification performance of single view compared with combined 2D views show improved classification accuracy of the latter, for nine species of Sciaenidae. The effects of shape description methods (shape indices, Procrustes analysis and elliptical Fourier analysis) on classification performance were evaluated. Procrustes analysis and elliptical Fourier analysis perform better than shape indices when single view is considered, but all perform equally well with combined views. A generic content-based image retrieval (CBIR) system that ranks dissimilarity (Procrustes distance) of otolith images was built to search query images without the need for detailed information of side (left or right), aspect (proximal or distal) and direction (positive or negative) of the otolith. Methods for the development of this automated classification system are discussed.
Fulltext Purpura Fulminans: A rare presentation of Streptococcus Pneumoniae infection

Teo HG, Wong JY, Ting TLL

BMJ Case Rep, 2017 Oct 20;2017.
PMID: 29054893 DOI: 10.1136/bcr-2017-221150

A previously healthy man presented with fever for 2 days and rapidly progressive purpuric rash for 1 day. He progressed into hypotension, disseminated intravascular coagulation and refractory shock despite resuscitation and early antibiotic commencement. Blood culture grew Streptococcus pneumoniae This case report highlights the fact that purpura fulminans can be a rare presentation of S. pneumoniae infection as well.
Appropriateness of antimicrobial prescribing in the high-burden emergency department of a tertiary hospital in Malaysia

Koh HP, Ambaras Khan R, Tay SL, Gill MK, Wong JY, Zainuddin MK

Int J Clin Pharm, 2021 Oct;43(5):1337-1344.
PMID: 33677792 DOI: 10.1007/s11096-021-01255-w

Background Appropriate antimicrobial prescribing in the emergency department (ED) is a challenge due to diagnostic uncertainty, time pressure, and clinical inertia. Objective To assess the appropriateness of antimicrobial prescribing in the ED. Setting This study was conducted in the inpatient ED of a tertiary hospital in Malaysia. Method We conducted a 6-month retrospective antimicrobial prescriptions analysis among ED patients who received intravenous antimicrobial. Antimicrobial prescriptions of conveniently selected adult patients were evaluated with the medication appropriateness index. Main outcome measure Appropriateness of antimicrobial prescribing was the primary outcome measure. Results We analysed 310 patients with 326 antimicrobial prescriptions. Ceftriaxone (41.1%, n = 134) and amoxicillin-clavulanate (36.5%, n = 119) were the most common antimicrobials prescribed. Respiratory infections (71.5%, n = 233) was the main indication for antimicrobial therapy in the ED. All antimicrobials prescribed were indicated as per the Malaysian antimicrobial guidelines. The overall rate of inappropriate antimicrobial prescribing was 53.1% (n = 173). Thirty-two (9.8%) antimicrobials were prescribed with inappropriate doses; the majority was related to beta-lactam/beta-lactamase dose (p = 0.002). One hundred and forty-three (43.9%) antimicrobials prescribed had alternatives with similar efficacy but were less costly; which referring to ceftriaxone usage (p
Reduction of central-line-associated bloodstream infection (CLABSI) in resource limited, nonintensive care unit (ICU) settings

Poh KW, Ngan CH, Wong JY, Ng TK, Mohd Noor N

Int J Health Care Qual Assur, 2020 Feb 25;ahead-of-print(ahead-of-print).
PMID: 32108452 DOI: 10.1108/IJHCQA-11-2019-0195

PURPOSE: There was limited study available on successful intervention for central-line-associated bloodstream infection (CLABSI) done at nonintensive care unit (ICU) and resources-limited setting. The objective of this study was to design, implement and evaluate a strategy to reduce CLABSI rate in non-ICU settings at general medical wards of Hospital Tuanku Ja'afar Seremban.
DESIGN/METHODOLOGY/APPROACH: Preinterventional study was conducted in one-month period of January 2019, followed by intervention period from February to March 2019. Postintervention study was conducted from April to July 2019. The CLABSI rates were compared between pre and postintervention periods. A multifaceted intervention bundle was implemented, which comprised (1) educational program for healthcare workers, (2) weekly audit and feedback and (3) implementation of central line bundle of care.
FINDINGS: There was a significant overall reduction of CLABSI rate between preintervention and postintervention period [incidence rate ratio (IRR) of 0.06 (95 percent CI, 0.01-0.33; P = 0.001)].
PRACTICAL IMPLICATIONS: CLABSI rates were reduced by a multifaceted intervention bundle, even in non-ICU and resource-limited setting. This includes a preinterventional study to identify the risk factors followed by a local adaption of the recommended care bundles. This study recommends resources-limited hospitals to design a strategy that is suitable for their own local setting to reduce CLABSI.
ORIGINALITY/VALUE: This study demonstrated the feasibility of a multifaceted intervention bundle that was locally adapted with an evidence-based approach to reduce CLABSI rate in non-ICU and resource-limited setting.
The effects of Euphorbia hirta on the ultrastructure of the murine liver, kidney and aorta

Wong JY, Chen YS, Chakravarthi S, Judson JP, L SR, Er HM

Exp Ther Med, 2013 Nov;6(5):1247-1250.
PMID: 24223653

Euphorbia hirta is widely used in traditional remedies and has been used cross-culturally for generations against maladies such as asthma, skin ailments and hypertension. Previous studies have demonstrated that Euphorbia hirta has antibacterial activity, and have also indicated certain antimolluscidal, antimalarial and anti-inflammatory properties, the latter of which have been suggested to be more pronounced than those of the rheumatological drug, etanercept. To date, no studies have identified the anatomical effects of this herb on the organs of test animals. This study aimed to identify the effects of Euphorbia hirta on the ultrastructure of the murine liver, kidney and aorta. A total of 32 adult male Sprague-Dawley rats were divided into four groups; three groups were fed with aqueous extracts of Euphorbia hirta at doses of 1, 10 and 50 mg/kg, respectively, every alternate day for 50 days, while one group served as a control. The animals were later sacrificed and the liver, kidney and aorta harvested for examination by electron microscopy. The aorta showed no ultrastructural changes across the groups. Renal and hepatic tissue from the treated groups demonstrated dose-dependent injuries, which showed architectural damage beginning in the nuclei and spreading outwards. Taking into consideration the properties of Euphorbia hirta that have been described in previous studies, in addition to the results from the present study, it appears that the herb may exhibit similar effects to those of the quinolone group of antibiotics. Further in-depth investigations are required into the potential effects of Euphorbia hirta, deleterious and otherwise.
Fulltext Gastroprotective Effects of Lion's Mane Mushroom Hericium erinaceus (Bull.:Fr.) Pers. (Aphyllophoromycetideae) Extract against Ethanol-Induced Ulcer in Rats

Wong JY, Abdulla MA, Raman J, Phan CW, Kuppusamy UR, Golbabapour S, et al.

Evid Based Complement Alternat Med, 2013;2013:492976.
PMID: 24302966 DOI: 10.1155/2013/492976

Hericium erinaceus is a famous tonic in oriental medicine. The gastroprotective effects of aqueous extract of H. erinaceus against ethanol-induced ulcers in Sprague Dawley rats were investigated. The possible involvements of lipid peroxidation, superoxide dismutase, and catalase were also investigated. Acute toxicity study was performed. The effects of aqueous extract of H. erinaceus on the ulcer areas, ulcer inhibition, gastric wall mucus, gross and histological gastric lesions, antioxidant levels, and malondialdehyde (MDA) contents were evaluated in ethanol-induced ulcer in vivo. In acute toxicity study, a high dose of 5 g/kg did not manifest any toxicological signs in rats. The extract promoted ulcer protection as ascertained by a significant reduction of the ulcer area. Furthermore, it exhibited a significant protection activity against gastric mucosal injury by preventing the depletion of antioxidant enzymes. The level of MDA was also limited in rat stomach tissues when compared with the ulcer control group. Immunohistochemistry showed upregulation of HSP70 protein and downregulation of BAX protein in rats pretreated with the extract. The aqueous extract of H. erinaceus protected gastric mucosa in our in vivo model. It is speculated that the bioactive compounds present in the extract may play a major role in gastroprotective activity.
Fulltext Clinical role of intrarenal venous flow patterns in decompensated heart failure with worsening renal function

Poh KW, Ngan CH, Tan SN, Burhan AA, Wong JY, Er CK, et al.

Ultrasound, 2023 May;31(2):119-125.
PMID: 37144225 DOI: 10.1177/1742271X221124467

INTRODUCTION: The clinical implication of intrarenal venous flow patterns in decompensated heart failure with worsening renal function is unknown. We aimed to study the relationship between intrarenal venous flow patterns, inferior vena cava volume status, caval index, clinical degree of congestion and the renal outcome in patients with decompensated heart failure and worsening renal function. Secondary objectives were to study the combined endpoint of readmission and mortality rate within 30 days (after the last scan) among intrarenal venous flow patterns and the effect of congestion status on the renal outcome.
METHODS: Twenty-three patients admitted for decompensated heart failure (ejection fraction ⩽40%) with worsening renal function (absolute increase in serum creatinine of 26.5 µmol/L or ⩾1.5-fold increment from baseline) were enrolled in this study. A total of 64 scans were performed. Patients were visited on day 0, 2, 4 and 7 (or earlier if discharged). Patients were called 30 days after discharge to evaluate readmission or mortality. Intrarenal venous flow patterns were ranked from continuous, interrupted, biphasic, to monophasic. Clinical congestion was scored from 0 to 7.
RESULTS: Intrarenal venous flow patterns had statistically significant positive correlations with inferior vena cava volume status (Spearman's ρ, 0.51; p
Vesicular Systems Containing Curcumin and Their Applications in Respiratory Disorders - A Mini Review

Chellappan DK, Hansbro PM, Dua K, Hsu A, Gupta G, Ng ZY, et al.

Pharm Nanotechnol, 2017;5(4):250-254.
PMID: 28786351 DOI: 10.2174/2211738505666170808094635

BACKGROUND: Vesicular systems like nanotechnology and liposomes are gaining tremendous attention lately in the field of respiratory diseases. These formulations enhance bioavailability of the drug candidate, which could be achieved through a novel drug delivery mechanism. Moreover, the therapeutic potential achieved through these systems is highly controllable over long durations of time providing better efficacy and patient compliance.
OBJECTIVE: The objective of this paper is to review the recent literature on vesicular drug delivery systems containing curcumin.
METHODS: We have collated and summarized various recent attempts made to develop different controlled release drug delivery systems containing curcumin which would be of great interest for herbal, formulation and biological scientists. There are several vesicular nanotechnological techniques involving curcumin which have been studied recently, targeting pulmonary diseases.
RESULTS: Different vesicular systems containing curcumin are being studied for their therapeutic potential in different respiratory diseases. There has been a renewed interest in formulations containing curcumin recently, primarily owing to the broad spectrum therapeutic potential of this miracle substance. Various types of formulations, containing curcumin, targeting different bodily systems have recently emerged and, nevertheless, the search for newer frontiers with this drug goes on.
CONCLUSION: This mini review, in this direction, tries to highlight the key research interventions employing vesicular systems of drug delivery with curcumin.
Seroprevalence of Leptospirosis in Working Dogs

Lau SF, Wong JY, Khor KH, Roslan MA, Abdul Rahman MS, Bejo SK, et al.

Top Companion Anim Med, 2017 Dec;32(4):121-125.
PMID: 29525230 DOI: 10.1053/j.tcam.2017.12.001

Working dogs are canine animals that have been trained to assist human beings in carrying out various tasks. They help in guarding property, performing rescues, assisting the visually impaired or physically handicapped, searching for drugs, explosives, and others. Leptospirosis is one of the most widespread zoonotic diseases in the world and a commonly occurring disease of the tropics and subtropics. In Malaysia, all working dogs are normally vaccinated with serovars, Pomona, Icterohaemorrhagiae, Canicola, and Grippotyphosa based on protocols recommended from other countries. The duration of immunity in vaccinated dogs for Leptospira can last up to 13 months; however, there is no full crossprotection between the different serovars. Five representative canine units from different government agencies in Malaysia (n = 96 dogs) were recruited in this study. For detection, the microscopic agglutination test was performed by incubating the serum from dogs with various serovars of leptospires, namely, Icterohaemorrhagiae, Canicola, Pomona, Grippotyphosa, Australis, Bataviae, Javanica, Tarassovi, Hebdomadis, Lai, and Pyrogenes. The plasma obtained was used for polymerase chain reaction (PCR) analysis, for the detection of 16S rRNA, and lipL 32 genes of Leptospira. Out of the 96 dogs sampled, only 3 dogs were positive toward serovars, Australis, Bataviae, and Javanica, based on the cutoff point at 1:80. The seroprevalence of canine leptospirosis in this population was 3.1% (n = 3/96). However, all 96 blood samples of working dogs tested negative for both pathogenic and nonpathogenic Leptospira genes. The results revealed that, by vaccination alone, working dogs were not fully protected against leptospirosis and could pose a risk to dog handlers. A preventative and control protocol for leptospirosis is warranted, and its implementation should be monitored and improved accordingly from time to time, in order to maintain a healthy condition in both working dogs and their handlers.
Immunological axis of curcumin-loaded vesicular drug delivery systems

Chellappan DK, Ng ZY, Wong JY, Hsu A, Wark P, Hansbro N, et al.

Future Med Chem, 2018 04 01;10(8):839-844.
PMID: 29620416 DOI: 10.4155/fmc-2017-0245

Several vesicular systems loaded with curcumin have found their way in the therapeutic applications of several diseases, primarily acting through their immunological pathways. Such systems use particles at a nanoscale range, bringing about their intended use through a range of complex mechanisms. Apart from delivering drug substances into target tissues, these vesicular systems also effectively overcome problems like insolubility and unequal drug distribution. Several mechanisms are explored lately by different workers, and interest over vesicular curcumin has been renewed in the past decade. This commentary discusses several immunological targets in which curcumin is employed in a vesicular form.
Assessing the potential of liposomes loaded with curcumin as a therapeutic intervention in asthma

Ng ZY, Wong JY, Panneerselvam J, Madheswaran T, Kumar P, Pillay V, et al.

Colloids Surf B Biointerfaces, 2018 Dec 01;172:51-59.
PMID: 30134219 DOI: 10.1016/j.colsurfb.2018.08.027

Curcumin a component of turmeric, which is derived from Curcuma longa is used as a colouring agent and as a dietary spice for centuries. Extensive studies have been done on the anti-inflammatory activity of curcumin along with its molecular mechanism involving different signalling pathways. However, the physicochemical and biological properties such as poor solubility and rapid metabolism of curcumin have led to low bioavailability and hence limits its application. Current therapies for asthma such as bronchodilators and inhaled corticosteroids (ICS) are aimed at controlling disease symptoms and prevent asthma exacerbation. However, this approach requires lifetime therapy and is associated with a constellation of side effects. This creates a clear unmet medical need and there is an urgent demand for new and more-effective treatments. The present study is aimed to formulate liposomes containing curcumin and evaluate for its anti-inflammatory effects on lipopolysaccharide (LPS)-induced inflammation on BCi-NS1.1 cell line. Curcumin and salbutamol liposomes were formulated using lipid hydration method. The prepared liposomes were characterized in terms of particle size, zeta potential, encapsulation efficiency and in-vitro release profile. The liposomes were tested on BCI-NS1.1 cell line to evaluate its anti-inflammatory properties. The various pro-inflammatory markers studied were Interleukin-6 (IL-6), Interleukin-8 (IL-8), Interleukin-1β (IL-1β) and Tumour Necrosis Factor-a (TNF-a). Additionally, molecular mechanics simulations were used to elucidate the positioning, energy minimization, and aqueous dispersion of the liposomal architecture involving lecithin and curcumin. The prepared curcumin formulation showed an average size and zeta potential of 271.3 ± 3.06 nm and -61.0 mV, respectively. The drug encapsulation efficiency of liposomal curcumin is 81.1%. Both curcumin-loaded liposomes formulation (1 μg/mL, 5 μg/mL) resulted in significant (p
Biological sex modifies aldosterone's secretion at a cellular level

Gholami SK, Tay CS, Lee JM, Zagoren E, Maris SA, Wong JY, et al.

J Endocrinol, 2021 11 24;252(1):1-13.
PMID: 34643545 DOI: 10.1530/JOE-21-0126

Inconsistencies have been reported on the effect of sex on aldosterone (ALDO) levels leading to clinical confusion. The reasons for these inconsistencies are uncertain but include estrogen and/or its receptor modulating target gene responses to mineralocorticoid receptor activation and ALDO secretagogues' levels. This study's goal was to determine whether ALDO's biosynthesis also differed by sex. Two approaches were used. First, plasma renin activity and aldosterone were measured in rats. Both were significantly higher in males. Secondly, using rat zona glomerulosa (ZG) cells, we assessed three ex vivo areas: (1) activity/levels of early steps in ALDO's biosynthesis (StAR and CYP11A1); (2) activity/levels of a late step (CYP11B2); and (3) the status of the mineralocorticoid receptor (MR)-mediated, ultrashort feedback loop. Females had higher expression of CYP11A1 and StAR and increased CYP11A1 activity (increased pregnenolone/corticosterone levels) but did not differ in CYP11B2 expression or activity (ALDO levels). Activating the ZG's MR (thereby activating the ultrashort feedback loop) reduced CYP11B2's activity similarly in both sexes. Exvivo, these molecular effects were accompanied, in females, by lower ALDO basally but higher ALDO with angiotensin II stimulation. In conclusion, we documented that not only was there a sex-mediated difference in the activity of ALDO's biosynthesis but also these differences at the molecular level help explain the variable reports on ALDO's circulating levels. Basally, both in vivo and ex vivo, males had higher ALDO levels, likely secondary to higher ALDO secretagogue levels. However, in response to acute stimulation, ALDO levels are higher in females because of the greater levels and/or activity of their StAR/CYP11A1.
Current attempts to implement microRNA-based diagnostics and therapy in cardiovascular and metabolic disease: a promising future

Thanikachalam PV, Ramamurthy S, Wong ZW, Koo BJ, Wong JY, Abdullah MF, et al.

Drug Discov Today, 2018 Mar;23(3):460-480.
PMID: 29107764 DOI: 10.1016/j.drudis.2017.10.020

MicroRNAs (miRNAs) are small, noncoding RNAs regulating gene expression at the post-translational level. miRNA-based therapeutic agents are important because of the functionality of miRNAs in regulating lipid and glucose metabolism and their role in the pathogenesis of metabolic disorders such as diabetes and obesity, where dysregulation leads to disease; they are also important in angiogenesis. miRNAs additionally serve as biomarkers in the diagnosis, prognosis and risk assessment of disease and in monitoring the response to treatment. Here, we provide a brief overview of progress in miRNA-based therapeutics in the preclinical and clinical setting and highlight the novel outcomes and opportunities in the diagnosis and treatment of metabolic conditions. In addition, we present the role of miRNAs in stem cell therapy which could have great potential in regenerative medicine.

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