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Omnidirectional Shape Memory Effect via Lyophilization of PEG Hydrogels

Chen D, Xia X, Wong TW, Bai H, Behl M, Zhao Q, et al.

Macromol Rapid Commun, 2017 Apr;38(7).
PMID: 28196300 DOI: 10.1002/marc.201600746

Device applications of shape memory polymers demand diverse shape changing geometries, which are currently limited to non-omnidirectional movement. This restriction originates from traditional thermomechanical programming methods such as uniaxial, biaxial stretching, bending, or compression. A solvent-modulated programming method is reported to achieve an omnidirectional shape memory behavior. The method utilizes freeze drying of hydrogels of polyethylene glycol networks with a melting transition temperature around 50 °C in their dry state. Such a process creates temporarily fixed macroporosity, which collapses upon heating, leading to significant omnidirectional shrinkage. These shrunken materials can swell in water to form hydrogels again and the omnidirectional programming and recovery can be repeated. The fixity ratio (R f ) and recovery ratio (R r ) can be maintained at 90% and 98% respectively upon shape memory multicycling. The maximum linear recoverable strain, as limited by the maximum swelling, is ≈90%. Amongst various application potentials, one can envision the fabrication of multiphase composites by taking advantages of the omnidirectional shrinkage from a porous polymer to a denser structure.
Angiogenic and wound healing potency of fermented virgin coconut oil: in vitro and in vivo studies

Ibrahim AH, Li H, Al-Rawi SS, Majid ASA, Al-Habib OA, Xia X, et al.

Am J Transl Res, 2017;9(11):4936-4944.
PMID: 29218091

OBJECTIVE: The process of wound healing involves activation of keratinocytes, fibroblasts, endothelial cells, etc. Angiogenesis is crucial during the process of wound healing. Virgin coconut oil is widely utilized in South Asia for various purposes including food, medicinal and industrial applications. This study aimed to evaluate the potency of fermented virgin coconut oil (FVCO) in angiogenesis and wound healing via both in vitro and in vivo assays.
METHODS: Human umbilical vein endothelial (HUVEC), fibroblast (CCD-18) and retinal ganglion (RGC-5) cells were cultured in medium containing different concentrations of FVCO. The proliferation, migration and morphological changes of cells were determined. The angiogenic effect of FVCO was evaluated by rat aortic assay. The therapeutic effect of FVCO on wound healing was further assessed in a wound excision model in Sprague Dawley rats. The expression of phospho-VEGFR2 (vascular endothelial growth factor receptor 2) in HUVECs was detected by Western blot.
RESULTS: FVCO (6 and 12 µg/mL) significantly improved the proliferation of HUVEC, CCD-18 and RGC-5 cells (P < 0.05 or 0.01). FVCO (25 µg/mL) markedly increased the migration ability of CCD-18 and RGC-5 cells (P < 0.05). FVCO did not affect cell morphology as indicated by fluorescein diacetate (FDA), rhodamine 123 and Hoechst staining. FVCO (25, 50 and 100 µg/mL) significantly stimulated the ex vivo blood vessel formation as compared with negative control (P < 0.05). Rats in FVCO group had significantly smaller wound size, higher wound healing percentage, and shorter wound closure time when compared with control group since day 8 (P < 0.05), suggesting that oral FVCO administration notably promoted the wound healing process. FVCO treatment (6 and 12 µg/mL) significantly enhanced the phospho-VEGFR2 expression in HUVECs (P = 0.006 and 0.000, respectively).
CONCLUSION: Our study confirms a high angiogenic and wound healing potency of FVCO that might be mediated by the regulation of VEGF signing pathway.
Fulltext Genome sequence of the hepatitis C virus subtype 6n isolated from malaysia

Ng KT, Lee YM, Al-Darraji HA, Xia X, Takebe Y, Chan KG, et al.

Genome Announc, 2013 Jan;1(1).
PMID: 23409272 DOI: 10.1128/genomeA.00168-12

We report the full genome sequence of hepatitis C virus (HCV) subtype 6n from Kuala Lumpur, Malaysia. Phylogenetic analysis of the isolate 10MYKJ032 suggests that Southeast Asia might be the origin for the HCV subtype 6n and highlights the possible spread of this lineage from Southeast Asia to other regions.
May Measurement Month 2018: an analysis of blood pressure screening results from Malaysia

Chia YC, Ching SM, Devaraj NK, Chew BN, Ooi PB, Mohamed M, et al.

Eur Heart J Suppl, 2020 Aug;22(Suppl H):H83-H85.
PMID: 32884479 DOI: 10.1093/eurheartj/suaa035

Hypertension continues to be the top global killer, contributing to over 10 million deaths annually. As prevalence and unawareness of hypertension remain high in Malaysia, this study was aimed to screen more individuals to identify those with undiagnosed hypertension. Respondents aged ≥18 years were recruited through opportunistic sampling at various screening sites including health clinics, hospitals, student health centres, universities, community halls, shopping malls, as well as through other health screening campaigns. Each respondent completed a questionnaire on socio-demographic, environmental, and lifestyle data. Anthropometric measurements as well as three blood pressure (BP) measurements were obtained from all participants. Hypertension was defined as a systolic BP ≥140 mmHg and/or diastolic BP ≥90 mmHg or taking antihypertensive medication. The total number of participants was 4866. The mean age of the participants was 39.8 (17.6) years with 61.1% female participants. Of the 4866 participants, 1405 (28.9%) had hypertension. The proportion of those aware of their hypertension status was 76.3% (1073/1405). The proportion of those with hypertension on medication was 71% (998/1405). Of those receiving antihypertensive treatment, 62.4% (623/998) had controlled BP. The proportion of hypertension in this study was 28.9%. The awareness rate of 76.3% compares favourably to a previously reported national level of 43.2%. Hence, BP screening programmes may be effective at increasing awareness and should be conducted annually.
Fulltext May Measurement Month 2017 blood pressure screening: findings from Malaysia-South-East Asia and Australasia

Chia YC, Ching SM, Chew BN, Devaraj NK, Siti Suhaila MY, Tay CL, et al.

Eur Heart J Suppl, 2019 Apr;21(Suppl D):D77-D79.
PMID: 31043885 DOI: 10.1093/eurheartj/suz061

Elevated blood pressure (BP) is a growing burden worldwide, leading to over 10 million deaths each year. However there are still many individuals, particularly in many countries in Asia, who have poor BP control. In Malaysia, less than two-fifths have achieved BP control. We participated in BP screening in Malaysia in conjunction with the May Measurement Month 2017 (MMM17), a global initiative by the International Society of Hypertension (ISH) aimed at screening more individuals for earlier detection of hypertension. A nationwide screening of adults aged ≥18 was carried out through health campaigns at clinics, hospitals, during family day events, and charity runs from 1 April 2017 to 31 May 2017 in 42 centres. We used the detailed protocol provided by ISH for data collection. A total of 4116 individuals were screened during MMM17. After multiple imputation, 32.4% (n = 1317/4059) had hypertension. Out of this, 63.9% (842/1317) of those with hypertension were on treatment. Of individuals receiving antihypertensive medication with an imputed BP, 59.5% (n = 496/834) of them had controlled BP. MMM17 was the largest organized BP screening campaign undertaken by health professionals in Malaysia. This study identified that 32.4% of screened individuals had hypertension and 59.5% individuals with treated hypertension had achieved BP control.
Fulltext The wheat Sr22, Sr33, Sr35 and Sr45 genes confer resistance against stem rust in barley

Hatta MAM, Arora S, Ghosh S, Matny O, Smedley MA, Yu G, et al.

Plant Biotechnol J, 2021 Feb;19(2):273-284.
PMID: 32744350 DOI: 10.1111/pbi.13460

In the last 20 years, stem rust caused by the fungus Puccinia graminis f. sp. tritici (Pgt), has re-emerged as a major threat to wheat and barley production in Africa and Europe. In contrast to wheat with 60 designated stem rust (Sr) resistance genes, barley's genetic variation for stem rust resistance is very narrow with only ten resistance genes genetically identified. Of these, only one complex locus consisting of three genes is effective against TTKSK, a widely virulent Pgt race of the Ug99 tribe which emerged in Uganda in 1999 and has since spread to much of East Africa and parts of the Middle East. The objective of this study was to assess the functionality, in barley, of cloned wheat Sr genes effective against race TTKSK. Sr22, Sr33, Sr35 and Sr45 were transformed into barley cv. Golden Promise using Agrobacterium-mediated transformation. All four genes were found to confer effective stem rust resistance. The barley transgenics remained susceptible to the barley leaf rust pathogen Puccinia hordei, indicating that the resistance conferred by these wheat Sr genes was specific for Pgt. Furthermore, these transgenic plants did not display significant adverse agronomic effects in the absence of disease. Cloned Sr genes from wheat are therefore a potential source of resistance against wheat stem rust in barley.