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  1. Loeillet S, Nicolas A
    DNA Repair (Amst), 2023 Jul;127:103514.
    PMID: 37244009 DOI: 10.1016/j.dnarep.2023.103514
    The evolutionarily conserved DNA polymerase delta (Polδ) plays several essential roles in eukaryotic DNA replication and repair, responsible for the synthesis of the lagging-strand, lower replicative mutagenesis via its proof-reading exonuclease activity and synthetizes both strands during break-induced replication. In Saccharomyces cerevisiae, the Polδ protein complex consists of three subunits encoded by the POL3, POL31 and POL32 genes. Surprisingly, in contrast to POL3 and POL31, the POL32 gene deletion was found to be viable but lethal in all other eukaryotes, raising the question to which extent the viability of the POL32 deletion in S. cerevisiae was species specific. To address this issue, we inactivated the POL32 gene in 10 evolutionary close or distant S. cerevisiae strains and found that POL32 was either essential (3 strains including SK1), non-essential (5 strains including the reference S288C strain) or confers a slow-growth phenotype (2 strains). Whole-genome sequencing of S288C/SK1 pol32∆ meiotic segregants identified the lethal/suppressor effect of the single Pol31-C43Y polymorphism. Consistently, the introduction of the Pol31-43C allele in the SK1 and West African (WA) pol32∆ mutants was sufficient to restore cell viability and wild-type growth upon introduction of two copies of POL31-43C in the SK1 haploid strain. Reciprocally, introduction of the SK1 POL31-43Y allele in the S288C pol32∆ mutant was lethal. Sequence analyses of the POL31 polymorphisms in the 1,011 yeasts genome dataset correlates with the strict occurrence of the POL31-43Y allele in the yeast African palm wine clade. Differently, the single Pol31-E400G polymorphism confers pol32∆ lethality in the Malaysian strain. In the yeast two-hybrid assay, we observed a weakened interaction between Pol3 and Pol31-43Y versus Pol31-43C suggesting an insufficient level of the Polδ holoenzyme stability/activity. Thus, the enigmatic non-essentiality of Pol32 in S. cerevisiae results from single Pol31 amino acid polymorphism and is clade rather than species specific.
    Matched MeSH terms: DNA-Directed DNA Polymerase/metabolism
  2. Syamimi Haslan, Lee YH, Goh CT, Ling LT
    Sains Malaysiana, 2018;47:2027-2033.
    Biosensor optik berasaskan hemoglobin (Hb) terpegun pada mikrosfera poli(n-butil akrilat-co-N-akriloksisuksinimida)
    [poli(nBA-NAS)] telah dibangunkan bagi mengesan kepekatan ion nitrit (NO2
    -
    ). Kompleks HEM ferum dalam Hb
    memangkinkan tindak balas penurunan ion NO2
    -
    kepada nitrik oksida (NO) lalu bergabung dengan deoksihemoglobin
    (HbFe2+) membentuk kompleks ferum-nitrosil-hemoglobin (HbFe2+-NO) yang berwarna hijau kekuningan. Spektrofotometer
    pantulan gentian optik digunakan untuk memantau kepekatan ion NO2
    -
    secara kuantitatif berdasarkan perubahan warna
    Hb terpegun pada mikrosfera poliakrilat daripada perang kemerahan ke hijau kekuningan pada panjang gelombang
    pantulan maksimum 668 nm. Pencirian terhadap biosensor nitrit reflektometrik melibatkan ujian kesan pH, kesan
    kepekatan Hb, julat rangsangan linear, kebolehasilan, jangka hayat dan kesan gangguan ion telah dijalankan. Biosensor
    ion NO2
    - optik terbangun memaparkan julat linear dinamik daripada 5 hingga 50 mg mL-1 (R2
    =0.9894) pada pH7.0 dengan
    had pengesanan (LOD) sebanyak 3.3 mg mL-1 dan nilai sisihan piawai relatif (RSD) kebolehasilan biosensor sebanyak
    5.8%. Jangka hayat biosensor optik nitrit tersebut adalah selama 36 hari dan majoriti ion asing yang sering wujud
    bersama ion NO2
    - dalam sampel air semula jadi tidak menunjukkan kesan gangguan yang bererti terhadap penentuan
    ion NO2
    -
    menggunakan biosensor optik terbangun kecuali ion Hg2+, Ag+, Br-
    dan S2-.
    Matched MeSH terms: DNA-Directed DNA Polymerase
  3. Balakrishnan KN, Abdullah AA, Bala JA, Jesse FFA, Abdullah CAC, Noordin MM, et al.
    Infect Genet Evol, 2021 06;90:104783.
    PMID: 33640483 DOI: 10.1016/j.meegid.2021.104783
    OBJECTIVE: This study investigated the suitability of siRNA targeting specific genes that cause inhibition of virus replication in vitro especially for the virus that capable of crossing placenta and we employed a novel transplacental rat cytomegalovirus that mimics infection in human.

    METHODS: Six unique siRNAs with three each targeting different regions of IE2 (ie2a, ie2b and ie2c) and DNA polymerase (dpa, dpb and dpc) were prepared and tested for antiviral activities. The efficacy as an antiviral was determined in in-vitro by measuring TCID50 virus titer, severity of virus-induced cytopathic effect (CPE), intracellular viral genome loads by droplet digital PCR, the degree of apoptosis in siRNA-treated cells and relative expression of viral mRNA in infected Rat Embryo Fibroblast (REF) cells.

    FINDINGS: Remarkably, the siRNAs: dpa, dpb and IE2b, significantly reduced virus yield (approximately >90%) compared to control group at day 18 post infection (p.i). Changes in CPE indicated that DNA polymerase siRNAs were capable of protecting cells against CMV infection at day 14 p.i with higher efficiency than GCV (at the concentration of 300 pmol). Gene expression analysis revealed a marked down regulation of the targeted DNA polymerase gene (73.9%, 96.0% and 90.7% for dpa, dpb and dpc siRNA, respectively) and IE2 gene (50.8%, 49.9% and 15.8% for ie2a, ie2b and ie2c siRNA, respectively) when measured by RT-qPCR. Intracellular viral DNA loads showed a significant reduction for all the DNA polymerase siRNAs (dpa: 96%, dpb: 98% and dpc:92) compared to control group (P 

    Matched MeSH terms: DNA-Directed DNA Polymerase/genetics; DNA-Directed DNA Polymerase/pharmacology
  4. Grismer, Lee L., Wood, Perry Lee Jr., Grismer, Jesse Leland
    Trop Life Sci Res, 2009;20(1):-.
    MyJurnal
    A new species of small, insular, forest floor skink, Sphenomorphus perhentianensis sp. nov., is described from Pulau Perhentian Besar of the Perhentian Archipelago, Peninsular Malaysia. This species is differentiated from all other 36 Sundaland species of Sphenomorphus based on a unique collection of morphological and colour pattern characteristics. These unique characteristics include a snout-vent length of 30.0 mm, 29 midbody scale rows, smooth as opposed to striated dorsal scales, 65 paravertebrals, 61 ventrals, 4 supraoculars, parietals contacting the posterior-most supraocular, 1 medially projecting superciliary scale, 2 loreals, 6 supralabials and infralabials, 10 lamellae beneath the fourth toe, smooth subdigital lamellae, enlarged preanal scales, no body bands, a dark brown, diffuse, dorsolateral stripe extending to just past the axilla, a cream coloured dorsolateral stripe on the nape and anterior-most portion of the body, and no cream coloured postorbital stripe. The discovery of a second endemic reptile in the Perhentian Archipelago underscores the unrealized biodiversity of its herpetofauna. Additional works will describe two additional species from the Perhentian Archipelago.
    Matched MeSH terms: DNA-Directed DNA Polymerase
  5. Ton SH, Lopez CG, Hasnah H
    PMID: 483004
    A study of Kuala Lumpur blood donors for HBsAG, anti-HBc and DNA polymeraes showed that 5.5% in the sample population was positive for HBsAG, 50.1% for anti-HBc and 10.1% for DNA polymerase activity. There was no significant difference of the HBsAG among the Malay, Chinese and Indian groups. However, a significant difference was observed for the anti-HBc and DNA polymerase activity between the Indian and the Malay/Chinese groups. Both analysis were significantly lower in the Indians but there was no significant difference between the Chinese and the Malays.
    Matched MeSH terms: DNA-Directed DNA Polymerase/blood*
  6. Thavoncharoensub N, Maruyama K, Heh CH, Hoong Leong K, Shi H, Shigematsu Y, et al.
    PMID: 30929604 DOI: 10.1080/15257770.2019.1586919
    8-OxodGTP is generated by the reaction between dGTP and reactive oxygen species and a considered mutagenic nucleotide. It can be incorporated into the duplex DNA during replication processes by the DNA polymerase, and thus the repair enzyme removes oxodGTP from the nucleotide pools in living cells. On the other hand, the γ-modified triphosphates show interesting properties for use as biological tools. Therefore, the γ-N-pyrenylalkyl-oxodGTP derivatives were synthesized and their effect on the enzymatic reactions were evaluated. The γ-N-pyrenylmethyl-oxodGTP was found to be accepted by the DNA polymerase just like oxodGTP, but showed a competitive inhibition property for the human oxodGTPase.
    Matched MeSH terms: DNA-Directed DNA Polymerase/chemistry
  7. Mohd Safwan Ibrahim, Ahmad Azuhairi Ariffin, Sri Ganesh Muthiah
    MyJurnal
    Introduction: Workers in health sector are exposed 5 times more workplace violence as compared to workers in other sectors. Their consequences can range from mild to severe, affecting the victim, quality of services and orga-nization. The objective is to evaluate the effectiveness of educational intervention on workplace violence among healthcare workers in health clinics. Methods: This study is a single blinded cluster randomized trial to see the ef-fectiveness of education intervention on coping with workplace violence involving 10 cluster clinics with total 82 respondents in each control and intervention group. Data was collected using pretested questionnaire at baseline, 1-month and 6-months post intervention. The analysis used were descriptive, compared mean at baseline, repeated measures of variance and Mixed Model. Results: Response rate 94% at 1-month due to loss to follow up. Majority of the respondents were female (82.3%), and Malays (83.5%). The prevalence of workplace violence was 27.4% and mostly involved psychological violence (95.6%). There were no significant different between control and interven-tion group characteristic at baseline. Repeated measures MANOVA test was conducted to test intervention effect on dependent variables. The results until 1-month time showed significant difference between intervention and control group on combination of the dependent variables over time in coping (F(1,162)=9.51, p=0.002, and η2=0.06), knowledge (F(1,162)=10.47, p=0.001, and η2=0.061) and confidence (F(1,162)=15.65, p
    Matched MeSH terms: DNA-Directed DNA Polymerase
  8. Rashid AA, Ghazali SS, Mohamad I, Mawardi M, Musa H, Roslan D
    PLoS One, 2020;15(7):e0235685.
    PMID: 32678838 DOI: 10.1371/journal.pone.0235685
    INTRODUCTION: House Officer (HO) Preparatory Courses in Malaysia are designed to prepare medical graduates to work as a HO. The courses are designed to address the issues related to lack of confidence and readiness to work, which could lead to stress and HO dropping out of work. The modules focus on how to prepare medical graduates into the real-life working scenario. Hence, we determined the effectiveness of a HO Preparatory Course on the level of confidence and readiness to work among medical graduates.

    METHODOLOGY: A quasi-experimental study was conducted at three time-points (pre-intervention, post-intervention and one-month after working as a HO) on the level of confidence and readiness of medical graduates. The intervention was the Medicorp module, which included information and training needed for the HO such as common clinical cases in the wards, case referrals, experience sharing and hands on clinical training. We recruited eligible participants undergoing the course between April-November 2018. The adapted IMU Student Competency Survey was used to measure the confidence and readiness levels, which were scored from a Likert scale of 1-5. The higher score indicated higher levels of confidence or readiness.

    RESULTS: A total of 239 participants were recruited at baseline (90% response rate). They were mostly female (77.8%), Malays (79.1%), single (90.0%), graduated overseas (73.6%), in 2018 (65.3%). The mean (SE) confidence scores significantly increased from 2.18 (1.00) pre-course to 3.50 (0.75) immediately after course and 3.79 (0.92) after one-month of work (p <0.001, η2 = 0.710). The mean (SE) readiness scores at pre-course, immediately and one-month post work were 2.36 (1.03), 3.46(0.78) and 3.70(0.90), respectively (p< 0.001, η2 = 0.612).

    CONCLUSION: The HO Preparatory Course module was effective in increasing levels of confidence and readiness for medical graduates, most of whom are overseas graduates; namely Egypt, Russia and Indonesia.

    Matched MeSH terms: DNA-Directed DNA Polymerase
  9. Vilcek S, Stadejek T, Ballagi-Pordány A, Lowings JP, Paton DJ, Belák S
    Virus Res, 1996 Aug;43(2):137-47.
    PMID: 8864203
    The genetic variability of classical swine fever virus was studied by comparative nucleotide sequence analysis of 76 virus isolates, collected during a half century from three continents. Parts of the E2 (gp55) and the polymerase gene coding regions of the viral genome were amplified by RT-PCR and DNA fragments of 254 and 207 bp, respectively, were sequenced. The comparative sequence analysis of the E2 region revealed two main phylogenetic groups of CSFV, indicating that the virus apparently evolved from two ancestor nodes. Group I (represented by Brescia strain) consisted of old and recent American and Asian viruses, as well as old English isolates from the 1950s. This group was subdivided into three subgroups, termed I.A-I.C. Group II (represented by Alfort strain) consisted of relatively recent isolates from Europe, together with strain Osaka, which was isolated in Japan from a pig of European origin. Based on genetic distances the group was divided into subgroups II.A and II.B. Malaysian isolates were branched into both groups, indicating multiple origins for contemporaneous outbreaks in that country. All ten vaccine strains tested were branched in group I, implying a common ancestor. The Japanese Kanagawa strain, isolated in 1974, and the British Congenital Tremor strain from 1964 were the most distinct variants of CSFV in our collection. The comparison of the nucleotide sequences of the polymerase coding region of 32 European strains distinguished subgroups II.A and II.B which were similar to the corresponding subgroups of the E2 phylogenetic tree. Thus, the results revealed that the E2 region and the polymerase coding regions seem to be appropriate for the grouping of CSFV isolates from all over the world, distinguishing two major groups of the virus. The reliability of these regions for phylogenetic analysis is indicated by the similarity of the results obtained from the two separate parts of the CSFV genome.
    Matched MeSH terms: DNA-Directed DNA Polymerase/genetics*
  10. Balakrishnan KN, Abdullah AA, Bala JA, Jesse FFA, Abdullah CAC, Noordin MM, et al.
    Virol J, 2020 Oct 27;17(1):164.
    PMID: 33109247 DOI: 10.1186/s12985-020-01436-5
    BACKGROUND: Cytomegalovirus (CMV) is an opportunistic pathogen that causes severe complications in congenitally infected newborns and non-immunocompetent individuals. Developing an effective vaccine is a major public health priority and current drugs are fronting resistance and side effects on recipients. In the present study, with the aim of exploring new strategies to counteract CMV replication, several anti-CMV siRNAs targeting IE2 and DNA polymerase gene regions were characterized and used as in combinations for antiviral therapy.

    METHODS: The rat embryo fibroblast (REF) cells were transfected with multi siRNA before infecting with CMV strain ALL-03. Viral growth inhibition was measured by tissue culture infectious dose (TCID50), cytopathic effect (CPE) and droplet digital PCR (ddPCR) while IE2 and DNA polymerase gene knockdown was determined by real-time PCR. Ganciclovir was deployed as a control to benchmark the efficacy of antiviral activities of respective individual siRNAs.

    RESULTS: There was no significant cytotoxicity encountered for all the combinations of siRNAs on REF cells analyzed by MTT colorimetric assay (P > 0.05). Cytopathic effects (CPE) in cells infected by RCMV ALL-03 had developed significantly less and at much slower rate compared to control group. The expression of targeted genes was downregulated successfully resulted in significant reduction (P DNA copies (dpb + dpc: 79%, 68%; dpb + ie2b: 68%, 60%; dpb + dpc + ie2b: 48%, 42%). Flow cytometry analysis showed a greater percentage of viable and early apoptosis of combined siRNAs-treated cells compared to control group. Notably, the siRNAs targeting gene regions were sequenced and mutations were not encountered, thereby avoiding the formation of mutant with potential resistant viruses.

    CONCLUSIONS: In conclusion. The study demonstrated a tremendous promise of innovative approach with the deployment of combined siRNAs targeting at several genes simultaneously with the aim to control CMV replication in host cells.

    Matched MeSH terms: DNA-Directed DNA Polymerase
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