Displaying publications 41 - 60 of 96 in total

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  1. Lee CK, Chan CYW, Gani SMA, Kwan MK
    Eur Spine J, 2017 11;26(11):2951-2960.
    PMID: 28819799 DOI: 10.1007/s00586-017-5266-5
    PURPOSE: This study aimed at studying the accuracy and safety of extra-pedicular screw insertion for dysplastic pedicles in AIS comparing cannulated screw system versus conventional screw system.

    METHODS: 104 AIS patients with 1524 pedicle screws were evaluated using CT scan. 302 screws were inserted in dysplastic pedicles using fluoroscopic guidance technique. 155 screws were inserted using a cannulated system (Group 1), whereas 147 screws were inserted using standard screws (Group 2). The pedicle perforations were assessed using a classification by Rao et al.; G0: no violation; G1: <2 mm perforation; G2: 2-4 mm perforation; and G3: >4 mm perforation). For anterior perforations, the pedicle perforations were assessed using a modified grading system (Grade 0: no violation, Grade 1: less than 4 mm perforation; Grade 2: 4 mm to 6 mm perforation; and Grade 3: more than 6 mm perforation).

    RESULTS: The perforation rate in Group 1 was 4.5% and in Group 2 was 15.6% (p = 0.001). Most of the perforations were anterior perforations (53.3%). The anterior perforation rate in Group 1 was 1.9% compared to 8.8% in Group 2 (p = 0.009). Group 1 has a medial perforation rate of 1.3% compared to Group 2, 6.1% (p = 0.031). The rate of critical pedicle perforation in Group 1 was 2.6% and in Group 2 was 6.8% (p = 0.102). In Group 1, there were no critical medial perforation but there was one G2 lateral perforation, one G2 superior perforation and two G3 anterior perforations. In Group 2, there were three G2 medial perforations, one G2 lateral perforation, one G2 anterior perforation and five G3 anterior perforations.

    CONCLUSION: Usage of cannulated screw system significantly increases the accuracy of pedicle screw insertion in dysplastic pedicles in AIS.

  2. Rahardiyan D, Moko EM, Tan JS, Lee CK
    Enzyme Microb Technol, 2023 Aug;168:110260.
    PMID: 37224591 DOI: 10.1016/j.enzmictec.2023.110260
    Plastic throughout the years is now one of the biggest world commodities and also the largest pollution to have an environmental impact, accumulating in landfills and also leaching into water systems and oceans. Especially with the shift to single-use disposable plastic, evermore positions plastics as the number one novel entity that pollutes the earth. This shift is also consistent in the food packaging industry. Managing plastic waste is still an issue at large, while the process of pyrolysis incineration still requires an obscene amount of energy that also does not resolve the problems with its environmental impact, the cost of mechanical-chemical degradation even outweighs the cost of producing the materials, and biodegradation process is a very slow and long process. Converting to bioplastics is one of the potential solutions to the global plastic issue. This review covers the potentials, limitations, challenges, progress and advancements of bioplastics, especially thermoplastic starch (starch-based bioplastic) in their efforts to replace petroleum plastics in food packaging and smart food packaging, especially for single-use (disposable) food packaging.
  3. Syed IA, Syed Sulaiman SA, Hassali MA, Thiruchelvum K, Lee CK
    Health Expect, 2015 Dec;18(6):2841-52.
    PMID: 25228140 DOI: 10.1111/hex.12268
    BACKGROUND: Understanding patients' knowledge and belief towards disease could play a vital role from an outcome perspective of disease management and HIV/AIDS patients are not exception to that.

    METHODS: Qualitative methodology was used to explore Malaysian HIV/AIDS patients' perspectives on disease and status disclosure. A semi structured interview guide was used to interview the patients and a saturation point was reached after the 13th interview. All interviews were audio-recorded and subjected to a standard content analysis framework.

    RESULTS: Understandings and beliefs towards HIV/AIDS and Perspective on disease disclosures were two main themes derived from patients' data. Beliefs towards causes and cure emerged as sub-themes under disease understandings while reasons for disclosure and non-disclosure were resulted as main sub-themes under disease disclosure. Majority of patients apprehended HIV/AIDS and its causes to acceptable extent, there were elements of spirituality and lack of education involved with such understandings. Though beliefs existed that knowing status is better than being ignorant, fear of stigma and discrimination, social consequences and family emotions were found important elements linked to disease non-disclosure.

    CONCLUSIONS: The outcomes provided basic information about patients' perceptions towards disease and status disclosure among HIV/AIDS patients which can help in the designing and improvising existing strategies to enhance disease awareness and acceptance and will also serve as baseline data for future research further focusing on this subject.
  4. Syed IA, Syed Sulaiman SA, Hassali MA, Lee CK
    Health Expect, 2015 Oct;18(5):1363-70.
    PMID: 24010818 DOI: 10.1111/hex.12116
    BACKGROUND: Health-related quality of life (HRQoL) is increasingly recognized as an important outcome and as a complement to traditional biological end points of diseases such as mortality. Unless there is a complete cure available for HIV/AIDS, development and implementation of a reliable and valid cross cultural quality of life measure is necessary to assess not only the physical and medical needs of HIV/AIDS people, but their psychological, social, environmental, and spiritual areas of life.
    METHODS: A qualitative exploration of HIV/AIDS patients' understanding, perceptions and expectations will be carried out with the help of semi structured interview guide by in depth interviews, while quantitative assessment of patient reported adverse drug reactions and their impact on health related quality of life will be carried out by using data collection tool comprising patient demographics, SF-12, Naranjo scale, and a clinical data sheet.
    RESULTS/OUTCOMES: The findings may serve as baseline QOL data of people living with HIV/AIDS in Malaysia and also a source data to aid construction of management plan to improve HIV/AIDS patients' QOL. It will also provide basic information about HIV/AIDS patients' perceptions, expectations and believes towards HIV/AIDS and its treatment which may help in designing strategies to enhance patients' awareness which in turn can help in addressing issues related to compliance and adherence.
    KEYWORDS: HIV/AIDS; adverse drug reactions; patients' perspective; quality of life
  5. Syed IA, Sulaiman SA, Hassali MA, Syed SH, Shan LH, Lee CK
    J Med Virol, 2016 May;88(5):790-7.
    PMID: 26399724 DOI: 10.1002/jmv.24389
    Suboptimal viral suppression and CD4 response to antiretroviral treatment (HAART) is known to cause poor outcomes with the increase cost of treatment. We aimed to assess factors associated with such control among HIV/AIDS patients in Malaysia. Four hundred and six HIV/AIDS patients, using Antiretroviral Therapy (ART) for at least the past three months, treated as outpatients at medication therapy adherence clinics (MTAC) were recruited. CD4 cell counts, viral load readings along with co-variants such as socio-demographic factors, adverse drug reactions, comorbidities, and medication record were obtained. Statistical Package for Social Sciences (SPSS(®) ) version 18 and STATA IC(®) version 12 were used for data analysis. CD4 counts were found highest among those within the age category 41-50 years (390.43 ± 272.28), female (402.64 ± 276.14), other ethnicities (400.20 ± 278.04), and participants with no formal education (414.87 ± 290.90). Patients experiencing adverse effects had a 2.28 (95%CI:1.25-4.18) fold greater risk of poor CD4 control, while patients with comorbidities had 2.46 (95%CI:1.02-5.91) fold greater risk of mild viral suppression. Adverse drug reactions, co-morbidities were found to be significantly associated with poor immunological and virological outcomes in HIV/AIDS patients. However, a comprehensive evaluation is needed to better understand other confounders.
    Study site: Medication therapy adherence clinic, Hospital Sungai Buloh, Selangor, Malaysia
  6. Hansen-Algenstaedt N, Chiu CK, Chan CY, Lee CK, Schaefer C, Kwan MK
    Spine (Phila Pa 1976), 2015 Sep 1;40(17):E954-63.
    PMID: 25929207 DOI: 10.1097/BRS.0000000000000958
    Retrospective study.
  7. Nissapatorn V, Lee CK, Cho SM, Rohela M, Anuar AK, Quek KF, et al.
    PMID: 19238664
    Three hundred and one sera of HIV/AIDS patients were tested for anti-Toxoplasma IgG antibody by ELISA technique. The seroprevalence of toxoplasmosis was 41.2% (95% CI: 35.5-46.9) in HIV/AIDS patients. The seroprevalence was significantly higher in the Malay (57.9%) than the Chinese (38.7%), followed by the Indian patients (29.6%) (p<0.05). No possible risk factor, such as contact with cats, consumption of uncooked meat, and history of blood transfusions was found to have any significant association with the presence of anti-Toxoplasma antibody in the study sample (p>0.05). Multivariate analysis was employed to find any association between Toxoplasma seroprevalence and a single subject having single or multiple risk factors. It was found that the association was not statistically significant (p>0.05). Among the HIV/AIDS study samples, 124 (41.2%) samples were found to have positive anti-Toxoplasma antibody, the association between the presence of anti-Toxoplasma antibody and CD4 cell count was determined but no statistically significant association was found (p>0.05). During the study period, only one case of active CNS toxoplasmosis was registered and the diagnostic criteria included: clinical presentations, CT scan finding, serological evidence of anti-Toxoplasma IgG antibody, and respose to anti-Toxoplasma therapy.
  8. Tan JS, Abbasiliasi S, Lalung J, Tam YJ, Murugan P, Lee CK
    Prep Biochem Biotechnol, 2021;51(3):260-266.
    PMID: 32876520 DOI: 10.1080/10826068.2020.1808793
    This study aimed at purification of phycocyanin (PC) from Phormidium tergestinum using an aqueous two-phase system (ATPS) comprised of polyethylene glycol (PEG) and salts. The partitioning efficiency of PC in ATPS and the effect of phase composition, pH, crude loading, and neutral salts on purification factor and yield were investigated. Results showed that PC was selectively partitioned toward bottom phase of the system containing potassium phosphate. Under optimum conditions of 20% (w/w) PEG 4000, 10% (w/w) potassium phosphate, 20% (v/v) crude load at pH 7, with addition of 0.5% (w/w) NaCl, PC from P. tergestinum was partially purified up to 5.34-fold with a yield of 87.8%. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed that the molecular weight of PC was ∼19 kDa. Results from this study demonstrated ATPS could be used as a potential approach for the purification of PC from P. tergestinum.
  9. Fatin AM, Mathana Sundram TK, Tan SSE, Seghayat MS, Lee CK, Rehman N, et al.
    Skin Res Technol, 2020 Jul;26(4):564-570.
    PMID: 31916334 DOI: 10.1111/srt.12831
    INTRODUCTION: Periorbital hyperpigmentation (POH) is among the commonest esthetic and dermatological complaints. Despite its frequency, there are inadequate information detailing its incidence and prevalence. This subsequently leads to lack of comprehensive POH classification and stratification of impact on an individual's general well'being. Malaysia, a multiracial country with an expansive expatriate population, provides a unique opportunity to identify demographics of POH and subsequently attempts to group this esthetic and dermatological entity.

    OBJECTIVE: This study aims to develop a new and clinically relevant POH classification system and to measure impact on quality of life of POH individuals.

    METHODS: One hundred patients with POH were enrolled, of which all underwent clinical assessment by a clinician. Objective assessment with mexameter and digital analysis were performed. All recruited patients also completed a questionnaire based on dermatology life quality index (DLQI).

    RESULTS: Assessments noted the commonest type of POH among the subjects was vascular (51%) with the least being pigmentary (6%). The location of POH majority involved both the upper and lower eyelids (65%). DLQI scoring shows that a majority (58%) did not disrupt their quality of life.

    CONCLUSION: Vascular type POH was the frequent most form observed, and involvement tends to occur on both eyelids. A majority of noted that POH does not affect they QOL, but the due consideration must be given in those whom are moderately and minimally affected. A thorough and comprehensive holistic approach is required in managing POH despite its focal presentation as it does affect a patient's quality of life.

  10. Tay ST, Wong PL, Chiu CK, Tang SN, Lee JL, Hamdan NW, et al.
    Eur Rev Med Pharmacol Sci, 2021 01;25(2):605-608.
    PMID: 33577013 DOI: 10.26355/eurrev_202101_24618
    OBJECTIVE: Nocardia kroppenstedtii was isolated from the spinal vertebral abscess of a 78-year-old patient presenting with mid-thoracic pain and bilateral lower limb weakness and numbness. The patient was on long-term immunosuppressive therapy with steroids for underlying autoimmune hemolytic anemia. Investigations showed a T5 pathological fracture and vertebra plana with the erosion of the superior and inferior endplates. There was evidence of paraspinal collection from the T4-T6 vertebrae with an extension into the spinal canal. Analysis of Nocardia 16S rRNA (99.9%, 1395/1396 nt) and secA1 gene (99.5%, 429/431 nt) fragments showed the highest sequence similarity with Nocardia kroppenstedtii type strain (DQ157924), and next with Nocardia farcinica (Z36936). The patient was treated with intravenous carbapenem and oral trimethoprim-sulfamethoxazole for four weeks, followed by another six months of oral trimethoprim-sulfamethoxazole. Despite the improvement of neurological deficits, the patient required assistive devices to ambulate at discharge. This study reports the first isolation of N. kroppenstedtii from the spinal vertebral abscess of a patient from Asia. Infections caused by N. kroppenstedtii may be underdiagnosed as the bacterium can be misidentified as N. farcinica in the absence of molecular tests in the clinical laboratory.
  11. Deepak AS, Ong JY, Choon D, Lee CK, Chiu CK, Chan C, et al.
    Malays Orthop J, 2017 Mar;11(1):41-46.
    PMID: 28435573 MyJurnal DOI: 10.5704/MOJ.1703.018
    INTRODUCTION: There is no large population size study on school screening for scoliosis in Malaysia. This study is aimed to determine the prevalence rate and positive predictive value (PPV) of screening programme for adolescent idiopathic scoliosis.

    MATERIALS AND METHODS: A total of 8966 voluntary school students aged 13-15 years old were recruited for scoliosis screening. Screening was done by measuring the angle of trunk rotation (ATR) on forward bending test (FBT) using a scoliometer. ATR of 5 degrees or more was considered positive. Positively screened students had standard radiographs done for measurement of the Cobb angle. Cobb angle of >10° was used to diagnose scoliosis. The percentage of radiological assessment referral, prevalence rate and PPV of scoliosis were then calculated.

    RESULTS: Percentage of radiological assessment referral (ATR >5°) was 4.2% (182/4381) for male and 5.0% (228/4585) for female. Only 38.0% of those with ATR >5° presented for further radiological assessment. The adjusted prevalence rate was 2.55% for Cobb angle >10°, 0.59% for >20° and 0.12% for >40°. The PPV is 55.8% for Cobb angle >10°, 12.8% for >20° and 2.6% for > 40°.

    CONCLUSIONS: This is the largest study of school scoliosis screening in Malaysia. The prevalence rate of scoliosis was 2.55%. The positive predictive value was 55.8%, which is adequate to suggest that the school scoliosis screening programme did play a role in early detection of scoliosis. However, a cost effectiveness analysis will be needed to firmly determine its efficacy.

  12. Choong CL, Wong HS, Lee FY, Lee CK, Kho JV, Lai YX, et al.
    Transplant Proc, 2018 Oct;50(8):2515-2520.
    PMID: 30316389 DOI: 10.1016/j.transproceed.2018.04.024
    BACKGROUND: Inhibition of calcineurin inhibitor (CNI) metabolism with diltiazem reduces the dose of tacrolimus required to achieve its therapeutic blood concentration in kidney transplant recipients (KTRs). This cost-savings maneuver is practiced in several countries, including Malaysia, but the actual impacts of diltiazem on tacrolimus blood concentration, dose-response relationship, cost-savings, and safety aspects are unknown.

    METHODS: This retrospective study was performed on all KTRs ≥18 years of age at our center from January 1, 2006 to December 31, 2015, who were prescribed diltiazem as tacrolimus-sparing agent. Blood tacrolimus trough level (TacC0) and other relevant clinical data for 70 eligible KTRs were reviewed.

    RESULTS: The dose of 1 mg tacrolimus resulted in a median TacC0 of 0.83 ± 0.52 ng/mL. With the introduction of a 90-mg/d dose diltiazem, there was a significant TacC0 increase to 1.39 ± 1.31 ng/mL/mg tacrolimus (P < .01). A further 90-mg increase in diltiazem to 180 mg/d resulted in a further increase of TacC0 to 1.66 ± 2.58 ng/mL/mg tacrolimus (P = .01). After this, despite a progressive increment of every 90-mg/d dose diltiazem to 270 mg/d and 360 mg/d, there was no further increment in TacC0 (1.44 ± 1.15 ng/mL/mg tacrolimus and 1.24 ± 0.94 ng/mL/mg tacrolimus, respectively [P < .01]). Addition of 180 mg/d diltiazem reduced the required tacrolimus dose to 4 mg/d, resulting in a cost-savings of USD 2045.92 per year (per patient) at our center. Adverse effects reported within 3 months of diltiazem introduction were bradycardia (1.4%) and postural hypotension (1.4%), which resolved after diltiazem dose reduction.

    CONCLUSION: Coadministration of tacrolimus and diltiazem in KTRs appeared to be safe and resulted in a TacC0 increment until reaching a 180-mg/d total diltiazem dose, at which point it began to decrease. This approach will result in a marked savings in immunosuppression costs among KTRs in Malaysia.

  13. Suppiah TSS, Sundram TKM, Tan ESS, Lee CK, Bustami NA, Tan CK
    Asia Pac J Clin Nutr, 2018 10 3;27(5):1141-1145.
    PMID: 30272862 DOI: 10.6133/apjcn.072018.01
    BACKGROUND AND OBJECTIVES: Acne vulgaris is a common skin condition among adolescents and young adults. Its relationship with the dietary intake is highly debatable and equivocal. This study aimed to identify the association between acne vulgaris and dietary intake among Malaysians.

    METHODS AND STUDY DESIGN: A case-control study was conducted involving 57 acne vulgaris patients and 57 age-, gender- and ethnicity-matched controls. All participants were aged 14 and above. The Comprehensive Acne Severity Scale (CASS) was used to categorise patients (grades 2 to 5) and controls (grades 0 to 1). Information such as the demographics, family history, smoking habits and dietary intake were collected using a self-administered questionnaire.

    RESULTS: In the patient arm, the gender ratio of male to female was 1.5:1. 43 patients (75.4%) had a family history of acne vulgaris. No significant association was found for acne in patients with a history of smoking. Milk consumption was significantly higher in patients (63.2%, n=36) versus controls (43.9%, n=25), (OR=2.19, p<0.05). In addition, chocolate consumption was also significantly higher in patients (43.9%, n=25) versus controls (24.6%, n=14), (OR=2.4, p<0.05). No significant association was found with the intakes of sweets, potatoes, chips, nuts, yoghurt, ice-cream or carbonated drinks.

    CONCLUSIONS: Dietary intake of milk and chocolate may play a role in acne vulgaris. Prospective cohort and intervention studies are recommended to explore whether a causal relationship might obtain.

  14. Ng ZJ, Zarin MA, Lee CK, Phapugrangkul P, Tan JS
    Arch Oral Biol, 2020 Feb;110:104617.
    PMID: 31794906 DOI: 10.1016/j.archoralbio.2019.104617
    Streptococcus mutans and Candida albicans are the main oral pathogens which contribute to dental caries that affects all ages of human being.

    OBJECTIVES: This study focuses on the potential of crude cell free supernatant (CCFS) from lactic acid bacteria (LAB) to inhibit of the growth of S. mutans UKMCC 1019.

    DESIGN: A total of 61 CCFS from LAB strains were screened for their inhibitory ability against S. mutans UKMCC 1019 by broth microdilution method. The selected LAB with highest antimicrobial activity was identified and its CCFS was characterized for pH stability, temperature tolerance, enzyme sensitivity, metabolism of carbohydrates, enzymatic activities and antimicrobial activity against S. mutans UKMCC 1019 and C. albicans UKMCC 3001 by well diffusion assay. The effect of CCFS on cell structure of S. mutans UKMCC 1019 was observed under transmission electron microscopy (TEM).

    RESULTS: The CCFS from isolate CC2 from Kimchi showed the highest inhibition against S. mutans UKMCC 1019, which was 76.46 % or 4406.08 mm2/mL and it was identified to be most closely related to Enterococcus faecium DSM 20477 based on 16 s rRNA sequencing. The CCFS of E. faecium DSM 20477 had high tolerance to acidic and alkaline environment as well as high temperature. It also shows high antifungal activities against C. albicans UKMCC 3001 with 2362.56 mm2/mL. Under TEM, the cell walls and the cytoplasm membrane of S. mutans UKMCC 1019 were disrupted by the antimicrobial substance, causing cell lysis.

    CONCLUSIONS: Hence, the CCFS from E. faecium DSM 20477 is a potential bacteriocin in future for the treatment of dental caries.

  15. Lee JHM, Loo CH, Tan WC, Lee CK, Jamil A, Khor YH
    Dermatol Ther, 2022 Jan;35(1):e15203.
    PMID: 34779102 DOI: 10.1111/dth.15203
    Methotrexate (MTX) is a first-line systemic psoriasis therapy with risk of liver fibrosis. Noninvasive tools for liver fibrosis screening are Fibroscan®, Fibrosis-4 (FIB-4) index, and aspartate aminotransferase-to-platelet ratio (APRI) index. To compare Fibroscan®, FIB-4, and APRI in detecting fibrosis, determine association of fibrosis with MTX cumulative dose, and explore risk factors for fibrosis. A case-control study involving psoriasis patients aged ≥18 years with MTX cumulative dose ≥1 g, with age and sex-matched MTX naïve psoriasis patients was performed. Noninvasive tools were used to assess liver fibrosis. Sixty-one patients on MTX and 54 controls participated. Fibroscan® detected fibrosis in 22 (36.1%) patients on MTX compared to 11 (19.6%) controls (p = 0.05). FIB-4 predicted fibrosis in 13 (21.3%) patients on MTX and in 10 (17.9%) controls (p = 0.64) while APRI diagnosed 7 (11.5%) versus 7 (12.5%), p = 0.65. No significant correlation between Fibroscan® assessed liver stiffness and MTX cumulative dose (p = 0.47). Independent risk factors for liver fibrosis were MTX use with raised alanine aminotransferase (OR = 68.56, 95% CI 8.26; 568.86, p 
  16. Mohd Zain NF, Paramasivam M, Tan JS, Lim V, Lee CK
    Biotechnol Prog, 2021 01;37(1):e3077.
    PMID: 32894656 DOI: 10.1002/btpr.3077
    The feasibility of using waste glycerol from the biodiesel industry for biosynthesis of polyhydroxyalkanoate (PHA) by Burkholderia cepacia BPT1213 was evaluated. Culture conditions were optimized by growing B. cepacia BPT1213 in mineral salt medium supplemented with 2% waste glycerol in a 2.5 L bioreactor. Response surface methodology was used to determine the influence of aeration rate (0.6-1.8 vvm), agitation speed (100-300 rpm), and cultivation period (48-72 hr) on PHA production. The optimum conditions for the growth and PHA accumulation were 1.5 vvm, 300 rpm, and 72 hr, with predicted values of 5.08 g/L cell dry weight (CDW), 66.07% PHA content, and 3.35 g/L total PHA concentration. Using these conditions, the experimental system produced 5.63 g/L of CDW with 64.00% wt/wt PHA content, which is threefold higher PHA concentration (3.60 g/L) compared to the non-optimized conditions. The melting temperature (Tm ) of purified PHA was 173.45 ± 1.05°C. In conclusion, the statistical approach was significantly increased the PHA production using waste glycerol as the sole carbon source.
  17. Ahmed SI, Syed Sulaiman SA, Hassali MA, Thiruchelvam K, Hasan SS, Lee CK
    J Infect Prev, 2017 Sep;18(5):242-247.
    PMID: 29317901 DOI: 10.1177/1757177416689723
    Background: Understanding patients' perspective towards HIV screening in Malaysia is pivotal to explore challenges faced by these individuals. This would be beneficial for developing local plans to improve the health-seeking behaviours among population at risk of HIV/AIDS.

    Methods: A qualitative research methodology was adopted to explore HIV/AIDS patients' views about disease screening. A semi-structured interview guide was used for in-depth patient interviews. All interviews were audio-recorded and were subjected to a standard content analysis framework for data analysis.

    Results: Most patients were positive about screening and the value of knowing about their status early. However, fear of social stigma, discrimination, lack of support system and lack of public understanding were identified as major concerns affecting their willingness to be screened. They were concerned about mandatory screening being implemented without improvement in support system and public education.

    Conclusions: Reluctance to seek HIV screening is an important factor contributing to transmission in developing countries. In the Malaysian context, efforts should be made to strengthen screening strategies especially in the most-at-risk populations to monitor the epidemic and target prevention strategies.

    Practice implications: In a multicultural context, HIV preventive strategies must include disease awareness, including measure to tackle barriers towards screening.

  18. Wang H, Li H, Lee CK, Mat Nanyan NS, Tay GS
    Polymers (Basel), 2022 Nov 22;14(23).
    PMID: 36501454 DOI: 10.3390/polym14235059
    Polyester is a kind of polymer composed of ester bond-linked polybasic acids and polyol. This type of polymer has a wide range of applications in various industries, such as automotive, furniture, coatings, packaging, and biomedical. The traditional process of synthesizing polyester mainly uses metal catalyst polymerization under high-temperature. This condition may have problems with metal residue and undesired side reactions. As an alternative, enzyme-catalyzed polymerization is evolving rapidly due to the metal-free residue, satisfactory biocompatibility, and mild reaction conditions. This article presented the reaction modes of enzyme-catalyzed ring-opening polymerization and enzyme-catalyzed polycondensation and their combinations, respectively. In addition, the article also summarized how lipase-catalyzed the polymerization of polyester, which includes (i) the distinctive features of lipase, (ii) the lipase-catalyzed polymerization and its mechanism, and (iii) the lipase stability under organic solvent and high-temperature conditions. In addition, this article also focused on the advantages and disadvantages of enzyme-catalyzed polyester synthesis under different solvent systems, including organic solvent systems, solvent-free systems, and green solvent systems. The challenges of enzyme optimization and process equipment innovation for further industrialization of enzyme-catalyzed polyester synthesis were also discussed in this article.
  19. Ali S, Tan SC, Lee CK, Yusoff Z, Haque MR, Mylonas A, et al.
    Sensors (Basel), 2023 Nov 02;23(21).
    PMID: 37960622 DOI: 10.3390/s23218922
    Software-Defined Networking (SDN), which is used in Industrial Internet of Things, uses a controller as its "network brain" located at the control plane. This uniquely distinguishes it from the traditional networking paradigms because it provides a global view of the entire network. In SDN, the controller can become a single point of failure, which may cause the whole network service to be compromised. Also, data packet transmission between controllers and switches could be impaired by natural disasters, causing hardware malfunctioning or Distributed Denial of Service (DDoS) attacks. Thus, SDN controllers are vulnerable to both hardware and software failures. To overcome this single point of failure in SDN, this paper proposes an attack-aware logical link assignment (AALLA) mathematical model with the ultimate aim of restoring the SDN network by using logical link assignment from switches to the cluster (backup) controllers. We formulate the AALLA model in integer linear programming (ILP), which restores the disrupted SDN network availability by assigning the logical links to the cluster (backup) controllers. More precisely, given a set of switches that are managed by the controller(s), this model simultaneously determines the optimal cost for controllers, links, and switches.
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