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  1. Tan JS, Teah KM, Hoe VC, Khairuddin A, Sellapan H, Hayati F, et al.
    Ann Med Surg (Lond), 2020 Nov;59:251-253.
    PMID: 33088499 DOI: 10.1016/j.amsu.2020.10.009
    Background: Adult intussusception is a relatively rare clinical entity. The majority of cases of intussusception in adults are due to a pathologic condition that serves as a lead point and requires surgery. Small bowel intussusception is usually caused by benign or malignant neoplasms appearing at the head of the invagination. Inflammatory fibroid polyp (IFP) of the small bowel is an unusual benign neoplastic lesion that has been rarely reported to cause intussusception, especially in the jejunum.

    Case presentation: We present a rare case of adult intussusception who presented with a triad of intestinal obstruction. Computed tomography revealed small bowel intussusception with bowel ischemia. Intraoperatively, she required resection of the small bowel and primary anastomosis. Macroscopic examination revealed a single pedunculated polyp, which is the lead point of intestinal obstruction and confirmed histologically.

    Conclusion: Inflammatory fibroid polyp should be considered as a cause of intussusception among adults with small bowel obstruction.

  2. Cao M, Liu Y, Yuan H, Qiu Y, Xie Q, Yi P, et al.
    J AOAC Int, 2020 Sep 01;103(5):1400-1405.
    PMID: 33241395 DOI: 10.1093/jaoacint/qsaa048
    BACKGROUND: Chewable areca products are popular in Asian countries, including India, Pakistan, Malaysia, and China. The major alkaloids present in areca products are guvacine, arecaidine, guvacoline, and arecoline which cause carcinogenicity and addiction.

    OBJECTIVE: The objective of this study was the quantitative analysis of the alkaloid content of areca chewable products from different countries and regions using HPLC-UV, as well as the benefit of their safety evaluation products.

    METHOD: An HPLC-UV method was established for qualitative and quantitative analyses of 65 batches of areca chewable products from different countries and regions. Additionally, similarity evaluation of chromatographic fingerprints was applied for data analysis.

    RESULTS: These results reveal a significant variation in the levels of areca alkaloids among tested products, specifically guvacoline (0.060-1.216 mg/g), arecoline (0.376-3.592 mg/g), guvacine (0.028-1.184 mg/g), and arecaidine (0.184-1.291 mg/g). There were significant differences in the alkaloid content of areca chewable products from different producing areas.

    CONCLUSIONS: The method will be useful in the safety evaluation of different areca chewable products.

    HIGHLIGHTS: The established HPLC-UV method can be adopted for safety evaluation of areca chewable products from different countries and regions due to its general applicability.

  3. Oslan SNH, Tan JS, Abbasiliasi S, Ziad Sulaiman A, Saad MZ, Halim M, et al.
    Microorganisms, 2020 Oct 24;8(11).
    PMID: 33114463 DOI: 10.3390/microorganisms8111654
    Growth of mutant gdhA Pasteurella multocida B:2 was inhibited by the accumulation of a by-product, namely ammonium in the culture medium during fermentation. The removal of this by-product during the cultivation of mutant gdhA P. multocida B:2 in a 2 L stirred-tank bioreactor integrated with an internal column using cation-exchange adsorption resin for the improvement of cell viability was studied. Different types of bioreactor system (dispersed and internal) with resins were successfully used for ammonium removal at different agitation speeds. The cultivation in a bioreactor integrated with an internal column demonstrated a significant improvement in growth performance of mutant gdhA P. multocida B:2 (1.05 × 1011 cfu/mL), which was 1.6-fold and 8.4-fold as compared to cultivation with dispersed resin (7.2 × 1010 cfu/mL) and cultivation without resin (1.25 × 1010 cfu/mL), respectively. The accumulation of ammonium in culture medium without resin (801 mg/L) was 1.24-fold and 1.37-fold higher than culture with dispersed resin (642.50 mg/L) and culture in the bioreactor integrated with internal adsorption (586.50 mg/L), respectively. Results from this study demonstrated that cultivation in a bioreactor integrated with the internal adsorption column in order to remove ammonium could reduce the inhibitory effect of this by-product and improve the growth performance of mutant gdhA P. multocida B:2.
  4. Wong CL, Yong CY, Muhamad A, Syahir A, Omar AR, Sieo CC, et al.
    Appl Microbiol Biotechnol, 2018 May;102(9):4131-4142.
    PMID: 29564523 DOI: 10.1007/s00253-018-8921-9
    Foot-and-mouth disease (FMD) is a major threat to the livestock industry worldwide. Despite constant surveillance and effective vaccination, the perpetual mutations of the foot-and-mouth disease virus (FMDV) pose a huge challenge to FMD diagnosis. The immunodominant region of the FMDV VP1 protein (residues 131-170) displayed on phage T7 has been used to detect anti-FMDV in bovine sera. In the present study, the functional epitope was further delineated using amino acid sequence alignment, homology modelling and phage display. Two highly conserved regions (VP1145-152 and VP1159-170) were identified among different FMDV serotypes. The coding regions of these two epitopes were fused separately to the T7 genome and displayed on the phage particles. Interestingly, chimeric phage displaying the VP1159-170 epitope demonstrated a higher antigenicity than that displaying the VP1131-170 epitope. By contrast, phage T7 displaying the VP1145-152 epitope did not react significantly with the anti-FMDV antibodies in vaccinated bovine sera. This study has successfully identified a smaller functional epitope, VP1159-170, located at the C-terminal end of the structural VP1 protein. The phage T7 displaying this shorter epitope is a promising diagnostic reagent to detect anti-FMDV antibodies in vaccinated animals.
  5. Chung WH, Tan RL, Chiu CK, Kwan MK, Chan C
    Malays Orthop J, 2020 Nov;14(3):170-173.
    PMID: 33403080 DOI: 10.5704/MOJ.2011.027
    Delayed post-operative spinal epidural haematoma (DPSEH) is diagnosed when the onset of symptoms is more than three days from the index surgery. DPSEH is a rare but serious complication of spinal surgery. Missed diagnosis will result in irreversible neurological deficit which may lead to permanent disabilities. We report two cases of DPSEH who presented with worsening neurological deficit four days after the index surgery. Magnetic resonance imaging (MRI) showed the presence of an epidural haematoma compressing the spinal cord. Surgical evacuation of haematoma were performed for both patients. Both patients experienced neurological improvement. Surgeons should have high index of suspicion to identify delayed onset of spinal epidural haematoma (SEH) and timely intervention should be taken to avoid irreversible neurological damage.
  6. Liew PS, Tan TH, Wong YC, Sim EUH, Lee CW, Narayanan K
    ACS Synth Biol, 2020 04 17;9(4):804-813.
    PMID: 32196315 DOI: 10.1021/acssynbio.9b00478
    TelN and tos are a unique DNA linearization unit isolated from bacteriophage N15. While being transferable, the TelN cleaving-rejoining activities remained stable to function on tos in both bacterial and mammalian environments. However, TelN contribution in linear plasmid replication in mammalian cells remains unknown. Herein, we investigated the association of TelN in linear tos-containing DNA (tos-DNA) replication in mammalian cells. Additionally, the mammalian origin of replication (ori) that is well-known to initiate the replication event of plasmid vectors was also studied. In doing so, we identified that both TelN and mammalian initiation sites were essential for the replication of linear tos-DNA, determined by using methylation sensitive DpnI/MboI digestion and polymerase chain reaction (PCR) amplification approaches. Furthermore, we engineered the linear tos-DNA to be able to retain in mammalian cells using S/MAR technology. The resulting S/MAR containing tos-DNA was robust for at least 15 days, with (1) continuous tos-DNA replication, (2) correct splicing of gene transcripts, and (3) stable exogenous gene expression that was statistically comparable to the endogenous gene expression level. Understanding the activities of TelN and tos in mammalian cells can potentially provide insights for adapting this simple DNA linearization unit in developing novel genetic engineering tools, especially to the eukaryotic telomere/telomerase study.
  7. Lim KS, Hills MD, Choo WY, Wong MH, Wu C, Tan CT
    Epilepsy Res, 2013 Oct;106(3):433-9.
    PMID: 23886655 DOI: 10.1016/j.eplepsyres.2013.06.014
    INTRODUCTION: There is a lack of study comparing the attitudes toward epilepsy between the teachers and general population, teachers and students, using a similar quantitative scale.
    METHODS: This study was performed in one primary and one secondary school in Kuala Lumpur, Malaysia, using the Public Attitudes Toward Epilepsy (PATE) scale.
    RESULTS: A total of 186 teachers aged 39.6±10.4 years completed the questionnaire. The mean scores in both personal and general domains of PATE scale were significantly better in the teachers, comparing to the scores in the secondary and college students reported in previous study (Lim et al., 2013; p<0.001 and <0.05, respectively). The mean scores in personal domain was significantly better in the teachers, comparing to the general population reported by Lim et al. (2012; p<0.001). This hold true when comparing teachers with general population with tertiary education, suggesting that the better attitude is specific to the job, rather than tertiary education generally. Subanalysis showed that the attitudes of teachers were significantly better than the general population and the students related to employment and social life, but were equally negative on issues directly related to education, such as placing children with epilepsy in regular classes.
    CONCLUSION: Teachers had more positive attitudes toward epilepsy as compared with the general population with tertiary education. Attitude to epilepsy may differ specific to types of work.
  8. Ting CY, Teh GC, Yu KL, Alias H, Tan HM, Wong LP
    Support Care Cancer, 2020 Apr;28(4):1703-1715.
    PMID: 31292755 DOI: 10.1007/s00520-019-04975-y
    PURPOSE: This study examined the prevalence of financial toxicity (FT) and associated factors among urologic cancer patients. The association between FT and health-related quality of life (HRQoL) was also investigated.

    METHODS: A total of 429 respondents diagnosed with urologic cancers (prostate cancer, bladder and renal cancer) from Sarawak General Hospital and Subang Jaya Medical Centre in Malaysia were interviewed using a structured questionnaire. Objective and subjective FT were measured by catastrophic health expenditure (healthcare-cost-to-income ratio greater than 40%) and the Personal Financial Well-being Scale, respectively. HRQoL was measured with the Functional Assessment of Cancer Therapy - General 7 Items scale.

    RESULTS: Objective and subjective FT were experienced by 16.1 and 47.3% of the respondents, respectively. Respondents who sought treatment at a private hospital and had out-of-pocket health expenditures were more likely to experience objective FT, after adjustment for covariates. Respondents who were female and had a monthly household income less than MYR 5000 were more likely to experience average to high subjective FT. Greater objective FT (OR = 2.75, 95% CI 1.09-6.95) and subjective FT (OR = 4.68, 95% CI 2.63-8.30) were associated with poor HRQoL.

    CONCLUSIONS: The significant association between both objective and subjective FT and HRQoL highlights the importance of reducing FT among urologic cancer patients. Subjective FT was found to have a greater negative impact on HRQoL.

  9. Chek MF, Kim SY, Mori T, Tan HT, Sudesh K, Hakoshima T
    iScience, 2020 May 22;23(5):101084.
    PMID: 32388399 DOI: 10.1016/j.isci.2020.101084
    Biodegradable polyester polyhydroxyalkanoate (PHA) is a promising bioplastic material for industrial use as a replacement for petroleum-based plastics. PHA synthase PhaC forms an active dimer to polymerize acyl moieties from the substrate acyl-coenzyme A (CoA) into PHA polymers. Here we present the crystal structure of the catalytic domain of PhaC from Chromobacterium sp. USM2, bound to CoA. The structure reveals an asymmetric dimer, in which one protomer adopts an open conformation bound to CoA, whereas the other adopts a closed conformation in a CoA-free form. The open conformation is stabilized by the asymmetric dimerization and enables PhaC to accommodate CoA and also to create the product egress path. The bound CoA molecule has its β-mercaptoethanolamine moiety extended into the active site with the terminal SH group close to active center Cys291, enabling formation of the reaction intermediate by acylation of Cys291.
  10. Tan MH, Austin CM, Hammer MP, Lee YP, Croft LJ, Gan HM
    Gigascience, 2018 03 01;7(3):1-6.
    PMID: 29342277 DOI: 10.1093/gigascience/gix137
    Background: Some of the most widely recognized coral reef fishes are clownfish or anemonefish, members of the family Pomacentridae (subfamily: Amphiprioninae). They are popular aquarium species due to their bright colours, adaptability to captivity, and fascinating behavior. Their breeding biology (sequential hermaphrodites) and symbiotic mutualism with sea anemones have attracted much scientific interest. Moreover, there are some curious geographic-based phenotypes that warrant investigation. Leveraging on the advancement in Nanopore long read technology, we report the first hybrid assembly of the clown anemonefish (Amphiprion ocellaris) genome utilizing Illumina and Nanopore reads, further demonstrating the substantial impact of modest long read sequencing data sets on improving genome assembly statistics.

    Results: We generated 43 Gb of short Illumina reads and 9 Gb of long Nanopore reads, representing approximate genome coverage of 54× and 11×, respectively, based on the range of estimated k-mer-predicted genome sizes of between 791 and 967 Mbp. The final assembled genome is contained in 6404 scaffolds with an accumulated length of 880 Mb (96.3% BUSCO-calculated genome completeness). Compared with the Illumina-only assembly, the hybrid approach generated 94% fewer scaffolds with an 18-fold increase in N50 length (401 kb) and increased the genome completeness by an additional 16%. A total of 27 240 high-quality protein-coding genes were predicted from the clown anemonefish, 26 211 (96%) of which were annotated functionally with information from either sequence homology or protein signature searches.

    Conclusions: We present the first genome of any anemonefish and demonstrate the value of low coverage (∼11×) long Nanopore read sequencing in improving both genome assembly contiguity and completeness. The near-complete assembly of the A. ocellaris genome will be an invaluable molecular resource for supporting a range of genetic, genomic, and phylogenetic studies specifically for clownfish and more generally for other related fish species of the family Pomacentridae.

  11. Yip CH, Taib NA, Tan GH, Ng KL, Yoong BK, Choo WY
    World J Surg, 2009 Jan;33(1):54-7.
    PMID: 18958521 DOI: 10.1007/s00268-008-9782-7
    Axillary nodal status is one of the most important prognostic factors in breast cancer. In the present study we used it to determine the predictors of axillary lymph node metastases in breast cancer and to determine if there is a group of patients in whom minimal axillary surgery is indicated.
  12. Tan CK, Said S, Rajandram R, Wang Z, Roslani AC, Chin KF
    World J Surg, 2016 08;40(8):1985-92.
    PMID: 27098538 DOI: 10.1007/s00268-016-3499-9
    INTRODUCTION: Disruption of normal gut function is a common side effect post abdominal surgery. It may result in reduced tolerance to oral nutrition and progress to postoperative ileus. Microbial cell preparation is beneficial as a pre-surgical nutritional supplement to aid in bowel recovery and promote the return of normal gut function following abdominal surgery. The aim of this study was to evaluate the efficacy of pre-surgical administration of microbial cell preparation in promoting the return of normal gut function.

    METHOD: The study is a randomized, double-blind, placebo-controlled trial. In total, 40 patients were recruited. Patients were randomized to receive either microbial cell preparation (n = 20) or placebo (n = 20) for 7 days prior to elective surgery. The primary end point was the time to return of normal gut function, while the secondary end point was the duration of hospital stay.

    RESULTS: The treatment group demonstrated significantly faster return of normal gut function with a median of 108.5 h (80-250 h) which was 48 h earlier than the placebo group at a median of 156.5 h (94-220 h), p = 0.022. The duration of hospital stay in the treatment group was also shorter at a median of 6.5 days (4-30 days), in comparison to the placebo group at 13 days (5-25 days), p = 0.012.

    CONCLUSION: Pre-surgical administration of microbial cell preparation promotes the return of normal gut function in patients after colorectal cancer surgery, thus associated with faster recovery and shorter duration of hospital stay.

  13. Yu Z, Liu J, Tan CSY, Scherman OA, Abell C
    Angew Chem Int Ed Engl, 2018 03 12;57(12):3079-3083.
    PMID: 29377541 DOI: 10.1002/anie.201711522
    The ability to construct self-healing scaffolds that are injectable and capable of forming a designed morphology offers the possibility to engineer sustainable materials. Herein, we introduce supramolecular nested microbeads that can be used as building blocks to construct macroscopic self-healing scaffolds. The core-shell microbeads remain in an "inert" state owing to the isolation of a pair of complementary polymers in a form that can be stored as an aqueous suspension. An annealing process after injection effectively induces the re-construction of the microbead units, leading to supramolecular gelation in a preconfigured shape. The resulting macroscopic scaffold is dynamically stable, displaying self-recovery in a self-healing electronic conductor. This strategy of using the supramolecular assembled nested microbeads as building blocks represents an alternative to injectable hydrogel systems, and shows promise in the field of structural biomaterials and flexible electronics.
  14. Krause HG, Wong V, Ng SK, Tan GI, Goh JTW
    Aust N Z J Obstet Gynaecol, 2019 08;59(4):585-589.
    PMID: 31146301 DOI: 10.1111/ajo.12990
    BACKGROUND: While pelvic floor ultrasound is commonly utilised in high-resource locations, our understanding of pelvic floor characteristics in women suffering with obstetric fistula and unrepaired fourth degree obstetric tears in low-resource areas is limited.

    AIMS: This study aimed to assess the pelvic floor ultrasound characteristics of Ugandan women suffering with obstetric fistula, unrepaired fourth degree obstetric tears and pelvic organ prolapse, and determine whether obstructed labour resulting in obstetric fistula causes more levator muscle defects compared to parous women without a history of obstructed labour.

    MATERIALS AND METHODS: This was a prospective study in western Uganda assessing 82 women with obstetric fistula, unrepaired fourth degree obstetric tears and pelvic organ prolapse with a pelvic floor ultrasound scan.

    RESULTS: Demographic characteristics were significantly different, with women suffering pelvic organ prolapse being older and more parous. Hiatal area on Valsalva was significantly smaller in the obstetric fistula group (mean 21.45 cm2 ) compared to non-obstetric fistula group (unrepaired fourth degree obstetric tears and pelvic organ prolapse; mean 30.44 cm2 ); a mean difference of 9.0 cm2 (95% CI: 5.4-12.6 cm2 , P 

  15. Tan DC, Idris KI, Kassim NK, Lim PC, Safinar Ismail I, Hamid M, et al.
    Pharm Biol, 2019 Dec;57(1):345-354.
    PMID: 31185767 DOI: 10.1080/13880209.2019.1610462
    Context:Paederia foetida L. (Rubiaceae) is an edible plant distributed in Asian countries including Malaysia. Fresh leaves have been traditionally used as a remedy for indigestion and diarrhea. Several phytochemical studies of the leaves have been documented, but there are few reports on twigs. Objective: This study investigates the enzyme inhibition of P. foetida twig extracts and compound isolated from them. In addition, in silico molecular docking of scopoletin was investigated. Materials and methods: Plants were obtained from two locations in Malaysia, Johor (PFJ) and Pahang (PFP). Hexane, chloroform and methanol extracts along with isolated compound (scopoletin) were evaluated for their enzyme inhibition activities (10,000-0.000016 µg/mL). The separation and identification of bio-active compounds were carried out using column chromatography and spectroscopic techniques, respectively. In silico molecular docking of scopoletin with receptors (α-amylase and α-glucosidase) was carried out using AutoDock 4.2. Results: The IC50 values of α-amylase and α-glucosidase inhibition activity of PFJ chloroform extract were 9.60 and 245.6 µg/mL, respectively. PFP chloroform extract exhibited α-amylase and α-glucosidase inhibition activity (IC50 = 14.83 and 257.2 µg/mL, respectively). The α-amylase and α-glucosidase inhibitory activity of scopoletin from both locations had IC50 values of 0.052 and 0.057 µM, respectively. Discussion and conclusions: Separation of PFJ chloroform extract afforded scopoletin (1), stigmasterol (2) and γ-sitosterol (3) and the PFP chloroform extract yielded (1), (2), (3) and ergost-5-en-3-ol (4). Scopoletin was isolated from this species for the first time. In silico calculations gave a binding energy between scopoletin and α-amylase of -6.03 kcal/mol.
  16. Wong TH, Tan TH, George UR, Kow KS, Liam CK
    Med J Malaysia, 2019 Jun;74(3):250-256.
    PMID: 31256186
    BACKGROUND: Lung cancer is one of the leading causes of cancer-related mortality worldwide. Pulmonary nodules are commonly encountered in clinical practice because of the recent implementation of low-dose CT lung screening programme, incidental finding on cardiac CT or CT for nonthoracic related disease. 18F-FDG PET-CT plays an important role in the management of pulmonary nodules.

    METHODS: In this pictorial review, we present six different scenarios of using 18F-FDG PET-CT in the management of suspicious pulmonary nodule or mass. The advantages and limitations of 18F-FDG PET-CT and Herder model are discussed.

    RESULTS: 18F-FDG PET-CT with risk assessment using Herder model provides added value in characterising indeterminate pulmonary nodules. Besides, 18F-FDG PET-CT is valuable to guide the site of biopsy and provide accurate staging of lung cancer.

    CONCLUSION: To further improve its diagnostic accuracy, careful history taking, and CT morphological evaluation should be taken into consideration when interpreting 18FFDG PET-CT findings in patients with these nodules.

  17. Lee WJ, Tan CP, Sulaiman R, Hee YY, Chong GH
    Food Chem, 2020 Jan 30;304:125427.
    PMID: 31494501 DOI: 10.1016/j.foodchem.2019.125427
    Solution-enhanced dispersion by supercritical carbon dioxide (SEDS) and spray drying (SD) were used to microencapsulate red palm oil (RPO) to prolong the functionality of carotenes and vitamin E. The protective effects provided by SEDS and SD were evaluated in terms of the oxidative stability (65 °C for 35 days), fatty acid compositions, color change and degradation kinetics of carotenes and vitamin E (25 °C, 45 °C, 65 °C, and 85 °C for up to 198 days). SEDS microcapsules (SEDS-M) were the most oxidatively stable (total oxidation (Totox): 26.5), followed by SD microcapsules (SD-M) (34.9) and RPO (56.7). Degradation of carotenes and vitamin E fitted well a first-order kinetic model (average absolute relative deviation = 2-16%). SEDS-M offered better protection to vitamin E (Ea = 36 kJ/mol), whereas SD-M provided better protection for α + β carotene (Ea = 29 kJ/mol). Overall, encapsulation protected RPO during storage, with SEDS-microencapsulated RPO performing better than SD-microencapsulated RPO.
  18. Lau ET, Tan SH, Antwertinger YJ, Hall T, Nissen LM
    J Pain Res, 2019;12:2441-2455.
    PMID: 31496787 DOI: 10.2147/JPR.S199017
    Background: People living with persistent pain in Australia often cannot access adequate care to manage their pain. Therefore, as the most accessible healthcare professionals, community pharmacists have an important role to play in helping to improve patient outcomes. Hence, it is important to investigate patient needs and expectations in terms of counseling interactions with pharmacists, along with pharmacists' approach to counseling interactions with these patients.

    Method: The nature of patient-pharmacist counseling interactions was explored with seven patients (one focus group), and 10 practicing pharmacists (two focus groups, three semi-structured interviews). The themes identified informed the development of an online survey that was advertised online to patients and pharmacists across Australia.

    Results: A total of 95 patients and 208 pharmacists completed the survey. Overall, more than half of patients (77/95) were satisfied with the care provided by their pharmacist, but only a third (71/205) of pharmacists were satisfied with the care they provided to patients. The majority of patients (67/94) reported that pharmacists provided good information about medications. This aligned with pharmacists' responses, as most reported focusing on medication side effects (118/188) and instructions for taking pain medication (93/183) during patient interactions. However, when asked about empathy and rapport from pharmacists, only half to two-thirds (48-61/95) of patients expressed positive views. Overall, half of the patients (39/75) wanted a caring, empathetic, respectful, and private conversation with the pharmacist, and nearly half (40/89) perceived the pharmacist's role as providing (new) information on alternative pharmacological and non-pharmacological therapies, including general advice on pain management.

    Conclusion: There was a disparity in the nature of the interaction and information that patients wanted from pharmacists, compared to what was provided by pharmacists. Training and education may help pharmacists to better engage in patient-centered care when interacting with people living with persistent pain, thereby improving health outcomes for these patients.

  19. Devasvaran K, Tan JJ, Ng CT, Fong LY, Yong YK
    Oxid Med Cell Longev, 2019;2019:1202676.
    PMID: 31531177 DOI: 10.1155/2019/1202676
    Malaysian Tualang honey (TH) is a known therapeutic honey extracted from the honeycombs of the Tualang tree (Koompassia excelsa) and has been reported for its antioxidant, anti-inflammatory, antiproliferative, and wound healing properties. However, the possible vascular protective effect of TH against oxidative stress remains unclear. In this study, the effects of TH on hydrogen peroxide- (H2O2-) elicited vascular hyperpermeability in human umbilical vein endothelial cells (HUVECs) and Balb/c mice were evaluated. Our data showed that TH concentrations ranging from 0.01% to 1.00% showed no cytotoxic effect to HUVECs. Induction with 0.5 mM H2O2 was found to increase HUVEC permeability, but the effect was significantly reversed attenuated by TH (p < 0.05), of which the permeability with the highest inhibition peaked at 0.1%. In Balb/c mice, TH (0.5 g/kg-1.5 g/kg) significantly (p < 0.05) reduced H2O2 (0.3%)-induced albumin-bound Evans blue leak, in a dose-dependent manner. Immunofluorescence staining confirmed that TH reduced actin stress fiber formation while increasing cortical actin formation and colocalization of caveolin-1 and β-catenin in HUVECs. Signaling studies showed that HUVECs pretreated with TH significantly (p < 0.05) decreased intracellular calcium release, while sustaining the level of cAMP when challenged with H2O2. These results suggested that TH could inhibit H2O2-induced vascular hyperpermeability in vitro and in vivo by suppression of adherence junction protein redistribution via calcium and cAMP, which could have a therapeutic potential for diseases related to the increase of both oxidant and vascular permeability.
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