Displaying publications 1 - 20 of 170 in total

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  1. Yoon SY, Wong SW, Lim J, Ahmad S, Mariapun S, Padmanabhan H, et al.
    J Med Genet, 2022 Mar;59(3):220-229.
    PMID: 33526602 DOI: 10.1136/jmedgenet-2020-107416
    BACKGROUND: Identifying patients with BRCA mutations is clinically important to inform on the potential response to treatment and for risk management of patients and their relatives. However, traditional referral routes may not meet clinical needs, and therefore, mainstreaming cancer genetics has been shown to be effective in some high-income and high health-literacy settings. To date, no study has reported on the feasibility of mainstreaming in low-income and middle-income settings, where the service considerations and health literacy could detrimentally affect the feasibility of mainstreaming.

    METHODS: The Mainstreaming Genetic Counselling for Ovarian Cancer Patients (MaGiC) study is a prospective, two-arm observational study comparing oncologist-led and genetics-led counselling. This study included 790 multiethnic patients with ovarian cancer from 23 sites in Malaysia. We compared the impact of different method of delivery of genetic counselling on the uptake of genetic testing and assessed the feasibility, knowledge and satisfaction of patients with ovarian cancer.

    RESULTS: Oncologists were satisfied with the mainstreaming experience, with 95% indicating a desire to incorporate testing into their clinical practice. The uptake of genetic testing was similar in the mainstreaming and genetics arm (80% and 79%, respectively). Patient satisfaction was high, whereas decision conflict and psychological impact were low in both arms of the study. Notably, decisional conflict, although lower than threshold, was higher for the mainstreaming group compared with the genetics arm. Overall, 13.5% of patients had a pathogenic variant in BRCA1 or BRCA2, and there was no difference between psychosocial measures for carriers in both arms.

    CONCLUSION: The MaGiC study demonstrates that mainstreaming cancer genetics is feasible in low-resource and middle-resource Asian setting and increased coverage for genetic testing.

  2. Xi B, Zong X, Kelishadi R, Litwin M, Hong YM, Poh BK, et al.
    J Clin Endocrinol Metab, 2020 04 01;105(4).
    PMID: 31723976 DOI: 10.1210/clinem/dgz195
    CONTEXT: No universal waist circumference (WC) percentile cutoffs used have been proposed for screening central obesity in children and adolescents.

    OBJECTIVE: To develop international WC percentile cutoffs for children and adolescents with normal weight based on data from 8 countries in different global regions and to examine the relation with cardiovascular risk.

    DESIGN AND SETTING: We used pooled data on WC in 113,453 children and adolescents (males 50.2%) aged 4 to 20 years from 8 countries in different regions (Bulgaria, China, Iran, Korea, Malaysia, Poland, Seychelles, and Switzerland). We calculated WC percentile cutoffs in samples including or excluding children with obesity, overweight, or underweight. WC percentiles were generated using the general additive model for location, scale, and shape (GAMLSS). We also estimated the predictive power of the WC 90th percentile cutoffs to predict cardiovascular risk using receiver operator characteristics curve analysis based on data from 3 countries that had available data (China, Iran, and Korea). We also examined which WC percentiles linked with WC cutoffs for central obesity in adults (at age of 18 years).

    MAIN OUTCOME MEASURE: WC measured based on recommendation by the World Health Organization.

    RESULTS: We validated the performance of the age- and sex-specific 90th percentile WC cutoffs calculated in children and adolescents (6-18 years of age) with normal weight (excluding youth with obesity, overweight, or underweight) by linking the percentile with cardiovascular risk (area under the curve [AUC]: 0.69 for boys; 0.63 for girls). In addition, WC percentile among normal weight children linked relatively well with established WC cutoffs for central obesity in adults (eg, AUC in US adolescents: 0.71 for boys; 0.68 for girls).

    CONCLUSION: The international WC cutoffs developed in this study could be useful to screen central obesity in children and adolescents aged 6 to 18 years and allow direct comparison of WC distributions between populations and over time.

  3. Lee SH, Yeoh ZX, Sachlin IS, Gazali N, Soelar SA, Foo CY, et al.
    Sci Rep, 2022 02 08;12(1):2111.
    PMID: 35136124 DOI: 10.1038/s41598-022-06029-6
    Alterations in the three chemosensory modalities-smell, taste, and chemesthesis-have been implicated in Coronavirus Disease 2019 (COVID-19), yet emerging data suggest a wide geographic and ethnic variation in the prevalence of these symptoms. Studies on chemosensory disorders in COVID-19 have predominantly focused on Caucasian populations whereas Asians remain understudied. We conducted a nationwide, multicentre cross-sectional study using an online questionnaire on a cohort of RT-PCR-confirmed adult COVID-19 patients in Malaysia between 6 June and 30 November 2020. The aim of our study was to investigate their presenting symptoms and assess their chemosensory function using self-ratings of perceived smell, taste, chemesthesis, and nasal blockage. In this cohort of 498 patients, 41.4% reported smell and/or taste loss when diagnosed with COVID-19, which was the commonest symptom. Blocked nose, loss of appetite, and gastrointestinal disturbances were independent predictors of smell and/or taste loss on multivariate analysis. Self-ratings of chemosensory function revealed a reduction in smell, taste, and chemesthesis across the entire cohort of patients that was more profound among those reporting smell and/or taste loss as their presenting symptom. Perceived nasal obstruction accounted for only a small proportion of changes in smell and taste, but not for chemesthesis, supporting viral disruption of sensorineural mechanisms as the dominant aetiology of chemosensory dysfunction. Our study suggests that chemosensory dysfunction in COVID-19 is more widespread than previously reported among Asians and may be related to the infectivity of viral strains.Study Registration: NMRR-20-934-54803 and NCT04390165.
  4. Abdelhafez MMA, Ahmed KAM, Ahmed NAM, Ismail MH, Daud MNM, Eldiasty AME, et al.
    Afr J Reprod Health, 2024 Mar 31;28(3):122-129.
    PMID: 38583076 DOI: 10.29063/ajrh2024/v28i3.13
    Menopausal hormone therapy (MHT) is known to increase the risk of venous thromboembolism (VTE), which includes deep vein thrombosis, pulmonary embolism, and less frequently cerebral vein thrombosis, but the absolute risk for a given patient is very low. After starting MHT, the risk of VTE seems to be at its highest, declining to the non-HRT user baseline level of risk after stopping. Whether estrogen-only or estrogen-progestin HRT combination is linked to a similar risk of VTE is unclear from the available evidence. The aim of this study is to evaluate the risks of developing VTE in relation to different types as well as different modes of administration of MHT through a database search including PubMed, MEDLINE, Google Scholar, Cochrane Library, and others in order to provide the women carers with the up-to-date and evidence-based guidelines and recommendations while counseling the post-menopausal women enquiring on use of hormonal therapies either to alleviate the menopausal symptoms or to prevent the long-term sequelae of estrogen deficiency.
  5. Chong DW, Jayaraj VJ, Ab Rahim FI, Syed Soffian SS, Azmi MF, Mohd Yusri MY, et al.
    PLoS One, 2024;19(4):e0299659.
    PMID: 38593177 DOI: 10.1371/journal.pone.0299659
    INTRODUCTION: Colorectal cancer is a growing global health concern and the number of reported cases has increased over the years. Early detection through screening is critical to improve outcomes for patients with colorectal cancer. In Malaysia, there is an urgent need to optimize the colorectal cancer screening program as uptake is limited by multiple challenges. This study aims to systematically identify and address gaps in screening service delivery to optimize the Malaysian colorectal cancer screening program.

    METHODS: This study uses a mixed methods design. It focuses primarily on qualitative data to understand processes and strategies and to identify specific areas that can be improved through stakeholder engagement in the screening program. Quantitative data play a dual role in supporting the selection of participants for the qualitative study based on program monitoring data and assessing inequalities in screening and program implementation in healthcare facilities in Malaysia. Meanwhile, literature review identifies existing strategies to improve colorectal cancer screening. Additionally, the knowledge-to-action framework is integrated to ensure that the research findings lead to practical improvements to the colorectal cancer screening program.

    DISCUSSION: Through this complex mix of qualitative and quantitative methods, this study will explore the complex interplay of population- and systems-level factors that influence screening rates. It involves identifying barriers to effective colorectal cancer screening in Malaysia, comparing current strategies with international best practices, and providing evidence-based recommendations to improve the local screening program.

  6. Syazwan A, Rafee BM, Hafizan J, Azman A, Nizar A, Izwyn Z, et al.
    PMID: 22570579 DOI: 10.2147/RMHP.S26567
    To meet the current diversified health needs in workplaces, especially in nonindustrial workplaces in developing countries, an indoor air quality (IAQ) component of a participatory occupational safety and health survey should be included.
  7. Tan SY, Poh BK, Chong HX, Ismail MN, Rahman J, Zarina AL, et al.
    Leuk. Res., 2013 Jan;37(1):14-20.
    PMID: 23099236 DOI: 10.1016/j.leukres.2012.09.005
    This study aimed to assess the physical activity levels of pediatric patients with acute leukemia undergoing chemotherapy. Thirty-eight pediatric patients and matched controls, aged 3-12 years old, were measured for weight, height, and other anthropometric parameters. Physical activity was assessed using actical accelerometer and activity log book. Patients recorded significantly lower mean total activity counts (26.2±30.2 cpm vs. 192.2±68.8 cpm; p<0.01) and spent more time in sedentary activities (1301±121 min vs. 1020±101 min; p<0.001) compared to controls. They also achieved fewer 1-5-min bouts of moderate-vigorous physical activity (MVPA) compared to controls (1.50±5.95 vs. 37.38±40.36; p<0.001). In conclusion, patients had lower physical activity level and intensity; and simple exercise intervention programs may be needed to minimize the detrimental effects of prolonged sedentary behaviors.
  8. Sivasampu S, Teh XR, Lim YMF, Ong SM, Ang SH, Husin M, et al.
    Prim Health Care Res Dev, 2020 08 13;21:e27.
    PMID: 32787978 DOI: 10.1017/S1463423620000250
    AIM: This paper describes the study protocol, which aims to evaluate the effectiveness of a multifaceted intervention package called 'Enhanced Primary Healthcare' (EnPHC) on the process of care and intermediate clinical outcomes among patients with Type 2 diabetes mellitus (T2DM) and hypertension. Other outcome measures include patients' experience and healthcare providers' job satisfaction.

    BACKGROUND: In 2014, almost two-thirds of Malaysia's adult population aged 18 years or older had T2DM, hypertension or hypercholesterolaemia. An analysis of health system performance from 2016 to 2018 revealed that the control and management of diabetes and hypertension in Malaysia was suboptimal with almost half of the patients not diagnosed and just one-quarter of patients with diabetes appropriately treated. EnPHC framework aims to improve diagnosis and effective management of T2DM, hypertension or hypercholesterolaemia and their risk factors by increasing prevention, optimising management and improving surveillance of diagnosed patients.

    METHODS: This is a quasi-experimental controlled study which involves 20 intervention and 20 control clinics in two different states in Malaysia, namely Johor and Selangor. The clinics in the two states were matched and randomly allocated to 'intervention' and 'control' arms. The EnPHC framework targets different levels from community to primary healthcare clinics and integrated referral networks.Data are collected via a retrospective chart review (RCR), patient exit survey, healthcare provider survey and an intervention checklist. The data collected are entered into tablet computers which have installed in them an offline survey application. Interrupted time series and difference-in-differences (DiD) analyses will be conducted to report outcomes.

  9. Tan WY, Yusof Khan AHK, Mohd Yaakob MN, Abdul Rashid AM, Loh WC, Baharin J, et al.
    BMC Neurol, 2021 Oct 12;21(1):395.
    PMID: 34641797 DOI: 10.1186/s12883-021-02427-x
    BACKGROUND: Transverse myelitis (TM) is a relatively uncommon condition, and vaccine-associated myelitis is even rarer. Concern regarding neurological complications following vaccination escalated following the report of TM during the safety and efficacy trials of the COVID-19 vaccine.

    CASE PRESENTATION: We report the first case of Longitudinal Extensive Transverse Myelitis (LETM) in Malaysia following administration of the chimpanzee adenovirus-vectored (ChAdOx1 nCoV-19) vaccine. A 25-year-old female presented with bilateral lower limb weakness and inability to walk with a sensory level up to T8 with absent visual symptoms. Urgent gadolinium-enhanced magnetic resonance imaging (MRI) of the spine showed long segment TM over the thoracic region. Cerebrospinal fluid autoantibodies for anti-aquaporin-4 and anti-myelin-oligodendrocyte were negative. A diagnosis of LETM following vaccination was made, and the patient was started on a high dose of intravenous methylprednisolone. The patient eventually made a recovery following treatment.

    CONCLUSION: LETM is a rare but serious adverse reaction following vaccination. Previously reported cases showed an onset of symptoms between 10 to 14 days post-vaccination, suggesting a delayed immunogenic reaction. However, the incidence of myelitis in COVID-19 is much more common, far greater than the risk associated with vaccination.

  10. Swaray S, Y Rafii M, Din Amiruddin M, Firdaus Ismail M, Jamian S, Jalloh M, et al.
    Insects, 2021 Mar 04;12(3).
    PMID: 33806613 DOI: 10.3390/insects12030221
    This study was conducted to assess the Elaeidobius kamerunicus (EK) population density among the biparental dura × pisifera hybrids' palms on deep peat-soil. Twenty-four hybrids derived from 10 genetic sources were used. Variance analysis showed that the EK population density varies between different oil palm hybrids, with a more noticeable variation of a low population mean in the male weevil across the hybrids. The highest weevil population mean/spikelet was attained on the third day of anthesis. The maximum monthly population of EK/spikelet (12.81 ± 0.23) and population density of EK (1846.49 ± 60.69) were recorded in January. Accordingly, 41.67% of the hybrids recorded an EK population density greater than the trial means of 973.68 weevils. Hybrid ECPHP550 had the highest mean of EK/spikelet (10.25 ± 0.11) and the highest population density of EK/palm (1241.39 ± 73.74). The parental mean population was 963.24 weevils and parent Deli-Banting × AVROS recorded the highest EK population density (1173.01). The overall results showed a notable disparity in the EK population among the biparental hybrids. Parental Deli-Banting × AVROS and hybrid ECPHP550 could be more useful to optimize the weevil population for pollination improvements in palm plantations. However, we suggest that volatile production should be included as a desirable trait in oil palm selective breeding.
  11. Ariffin N, Abdullah R, Rashdan Muad M, Lourdes J, Emran NA, Ismail MR, et al.
    Plasmid, 2011 Sep;66(3):136-43.
    PMID: 21827784 DOI: 10.1016/j.plasmid.2011.07.002
    Polyhydroxybutyrate-co-hydroxyvalerate (PHBV) is a polyhydroxyalkanoate (PHA) bioplastic group with thermoplastic properties is thus high in quality and can be degradable. PHBV can be produced by bacteria, but the process is not economically competitive with polymers produced from petrochemicals. To overcome this problem, research on transgenic plants has been carried out as one of the solutions to produce PHBV in economically sound alternative manner. Four different genes encoded with the enzymes necessary to catalyze PHBV are bktB, phaB, phaC and tdcB. All the genes came with modified CaMV 35S promoters (except for the tdcB gene, which was promoted by the native CaMV 35S promoter), nos terminator sequences and plastid sequences in order to target the genes into the plastids. Subcloning resulted in the generation of two different orientations of the tdcB, pLMIN (left) and pRMIN (right), both 17.557 and 19.967 kb in sizes. Both plasmids were transformed in immature embryos (IE) of oil palm via Agrobacterium tumefaciens. Assays of GUS were performed on one-week-old calli and 90% of the calli turned completely blue. This preliminary test showed positive results of integration. Six-months-old calli were harvested and RNA of the calli were isolated. RT-PCR was used to confirm the transient expression of PHBV transgenes in the calli. The bands were 258, 260, 315 and 200 bp in size for bktB, phaB, phaC and tdcB transgenes respectively. The data obtained showed that the bktB, phaB, phaC and tdcB genes were successfully integrated and expressed in the oil palm genome.
  12. Drewnowski A, Mognard E, Gupta S, Ismail MN, Karim NA, Tibère L, et al.
    Nutrients, 2020 May 25;12(5).
    PMID: 32466102 DOI: 10.3390/nu12051530
    Countries in South East Asia are undergoing a nutrition transition, which typically involves a dietary shift from plant to animal proteins. To explore the main drivers of protein consumption, the SCRiPT (Socio Cultural Research in Protein Transition) study recruited a population sample in Malaysia (N = 1604). Participants completed in-person 24 h dietary recalls and socio-demographic surveys. Energy and nutrient intakes were estimated using Nutritionist Pro. A novel recipe-based frequency count coded protein sources as meat (chicken, beef, pork, and mutton), fish, eggs, dairy, and plants (cereals, pulses, tubers). Dietary intakes and frequencies were examined by gender, age, income, education, ethnicity, religion, and family status, using ANOVAs and general linear models. Energy intakes were 1869 kcal/d for men and 1699 kcal/d for women. Protein intakes were 78.5 g/d for men and 72.5 g/d for women. Higher energy and protein intakes were associated with Chinese ethnicity, higher education and incomes. Frequency counts identified plant proteins in 50% of foods, followed by meat (19%), fish (12%), eggs (12%), and dairy (7%). Most frequent source of meat was chicken (16%) rather than pork or beef (1.5% each). In bivariate analyses, animal protein counts were associated with younger age, higher education and incomes. In mutually adjusted multivariate regression models, animal proteins were associated with education and ethnicity; plant proteins were associated with ethnicity and religion. Protein choices in Malaysia involve socio-cultural as well as economic variables.
  13. Balaji R, Lee Siang H, Yaakob O, Koh KK, Adnan FAB, Ismail NB, et al.
    Environ Technol, 2018 May;39(9):1102-1114.
    PMID: 28425309 DOI: 10.1080/09593330.2017.1321691
    Waste heat recovery from shipboard machineries could be a potential source for heat treatment of ballast water. Similar to a shipboard schematic arrangement, a laboratory-scale engine-heat exchanger set-up harvesting waste heat from jacket water and exhaust gases was erected to test the level of species' mortalities. Mortalities were also assessed under experimental conditions for cultured and natural plankton communities at laboratory level. Effect of pump impellers on species' mortalities were also tested. Exposures between 60°C and 70°C for 60 sec resulted in 80-100% mortalities. Mortalities due to pump impeller effects were observed in the range of 70-100% for zooplankton. On the laboratory-scale arrangement, >95% mortalities of phytoplankton, zooplankton and bacteria were recorded. It was demonstrated that the temperature of tropical sea waters used as secondary coolant can be raised to cause species' mortalities, employing engine exhaust gases. The results also indicated that pump impeller effects will enhance species' mortalities. The limitations of the shipboard application of this method would be the large ballast volumes, flow rates and time for treatment.
  14. Hon MK, Mohamad MS, Mohamed Salleh AH, Choon YW, Mohd Daud K, Remli MA, et al.
    Interdiscip Sci, 2019 Mar;11(1):33-44.
    PMID: 30758766 DOI: 10.1007/s12539-019-00324-z
    In recent years, metabolic engineering has gained central attention in numerous fields of science because of its capability to manipulate metabolic pathways in enhancing the expression of target phenotypes. Due to this, many computational approaches that perform genetic manipulation have been developed in the computational biology field. In metabolic engineering, conventional methods have been utilized to upgrade the generation of lactate and succinate in E. coli, although the yields produced are usually way below their theoretical maxima. To overcome the drawbacks  of such conventional methods, development of hybrid algorithm is introduced to obtain an optimal solution by proposing a gene knockout strategy in E. coli which is able to improve the production of lactate and succinate. The objective function of the hybrid algorithm is optimized using a swarm intelligence optimization algorithm and a Simple Constrained Artificial Bee Colony (SCABC) algorithm. The results maximize the production of lactate and succinate by resembling the gene knockout in E. coli. The Flux Balance Analysis (FBA) is integrated in a hybrid algorithm to evaluate the growth rate of E. coli as well as the productions of lactate and succinate. This results in the identification of a gene knockout list that contributes to maximizing the production of lactate and succinate in E. coli.
  15. Wong CY, Tham JS, Foo CN, Ng FL, Shahar S, Zahary MN, et al.
    Biosaf Health, 2023 Feb;5(1):37-44.
    PMID: 36588928 DOI: 10.1016/j.bsheal.2022.12.005
    Vaccination is crucial in controlling the spread of the coronavirus disease 2019 (COVID-19) that triggered the pandemic, but herd immunity can only work with high vaccination coverage in the population. This study aims to measure the COVID-19 knowledge level and determine the factors influencing COVID-19 vaccination intention among university students in Malaysia. A cross-sectional online survey was carried out with 1,274 Malaysian university students in July 2021. Univariate and multivariate analyses were employed to examine the relationships between the study variables. Results showed that the majority of university students had an acceptable level of knowledge of COVID-19. The knowledge, risk perception of COVID-19, social norms, and perceived benefit of COVID-19 vaccination were positively associated with vaccination intention. However, perceived trust in information sources of COVID-19 vaccination and the government's response to COVID-19 did not affect the university students' desire to receive the vaccination. These findings are essential for health policymakers and healthcare providers to implement evidence-based interventions to increase COVID-19 vaccination uptake among university students.
  16. Yahya MM, Ismail MP, Ramanathan S, Kadir MN, Azhar A, Ibrahim NBC, et al.
    Biomedicines, 2023 Feb 11;11(2).
    PMID: 36831061 DOI: 10.3390/biomedicines11020525
    Breast carcinoma is the most common cancer of women in Malaysia. The most common sites of metastasis are the lung, liver, bone and brain. A 45-year-old lady was diagnosed with left invasive breast carcinoma stage IV (T4cN1M1) with axillary lymph nodes and lung metastasis. She was noted to have a cervical mass through imaging, and biopsy showed CIN III. Post chemotherapy, the patient underwent left simple mastectomy with examination under anaesthesia of the cervix, cystoscopy and staging. The cervical histopathological examination (HPE) showed squamous cell carcinoma, and clinical staging was 2A. The breast tissue HPE showed invasive carcinoma with triple receptors positivity. The patient was given tamoxifen and put on concurrent chemoradiotherapy (CCRT) for the cervical cancer. The management of each pathology of this patient involved a multi-disciplinary team that included surgeons, oncologists, gynaecologists, pathologists and radiologists. Due to the complexity of the case with two concurrent cancers, the gene expression profiles may help predict the patient's clinical outcome.
  17. Haque M, Sa B, Majumder MAA, Islam MZ, Othman NSAB, Lutfi SNNB, et al.
    Ann Afr Med, 2018;17(4):183-188.
    PMID: 30588931 DOI: 10.4103/aam.aam_57_17
    BACKGROUND: Empathy is one of the cardinal components for physician-patient relationships, optimal outcomes in patient care, improved patient satisfaction, greater adherence to therapy, and lower malpractice liability. It is also considered an essential quality for health-care professionals to practice medicine. The aim of the present study was to assess the empathy level of medical students of Universiti Pertahanan Nasional Malaysia (UPNM) National Defense University of Malaysia, Kuala Lumpur, Malaysia.

    METHODS: This was a cross-sectional study conducted in 2017 which recruited medical students of UPNM. The Empathy Quotient, a self-reported questionnaire, was utilized for data collection. The total empathy score of the questionnaire is 80.

    RESULTS: Majority of the respondents were male (60.9%), year-V students (26.6%), Malay (70.5%), and cadet officer (69.6%). The overall mean score achieved by the respondents was 36.76 ± 9.18, and 74.4% of the respondents scored more than 30. The empathy scores of the students were significantly affected by the gender (t = 2.371; df = 205; P < 0.05), year of study (F = 2.553; df = 4/202; P < 0.05), and examination grades (F = 3.488; df = 2/204; P < 0.05). The findings showed that female students are more empathetic than their male counterparts. Further, the post hoc Tukey test analysis revealed that Year-V students are more empathetic than their junior counterparts and students who got highest grade are more empathetic.

    CONCLUSIONS: To improve the empathy level of the UPNM medical students, appropriate educational strategies and interventions should be designed and implemented in the curriculum to inculcate, maintain, and enhance empathy.

  18. Nevame AYM, Xia L, Nchongboh CG, Hasan MM, Alam MA, Yongbo L, et al.
    Biomed Res Int, 2018;2018:8120281.
    PMID: 30105248 DOI: 10.1155/2018/8120281
    Tomato yellow leaf curl virus (TYLCV) responsible for tomato yellow leaf curl disease (TYLCD) causes a substantial decrease in tomato (Solanum lycopersicum L.) yield worldwide. The use of resistant variety as a sustainable management strategy has been advocated. Tremendous progress has been made in genetically characterizing the resistance genes (R gene) in tomato. Breeding tomato for TYLCV resistance has been based mostly on Ty-3 as a race-specific resistance gene by introgression originating from wild tomato species relatives. Improvement or development of a cultivar is achievable through the use of marker-assisted selection (MAS). Therefore, precise and easy use of gene-targeted markers would be of significant importance for selection in breeding programs. The present study was undertaken to develop a new marker based on Ty-3 gene sequence that can be used for MAS in TYLCV resistant tomato breeding program. The new developed marker was named ACY. The reliability and accuracy of ACY were evaluated against those of Ty-3 linked marker P6-25 through screening of commercial resistant and susceptible tomato hybrids, and genetic segregation using F2 population derived from a commercial resistant hybrid AG208. With the use of bioinformatics and DNA sequencing analysis tools, deletion of 10 nucleotides was observed in Ty-3 gene sequence for susceptible tomato variety. ACY is a co-dominant indel-based marker that produced clear and strong polymorphic band patterns for resistant plant distinguishing it from its susceptible counterpart. The obtained result correlates with 3:1 segregation ratio of single resistant dominant gene inheritance, which depicted ACY as gene-tag functional marker. This marker is currently in use for screening 968 hybrids varieties and one thousand breeding lines of tomato varieties stocked in Jiangsu Green Port Modern Agriculture Development Company (Green Port). So far, ACY has been used to identify 56 hybrids and 51 breeding lines. These newly detected breeding lines were regarded as potential source of resistance for tomato breeding. This work exploited the sequence of Ty-3 and subsequently contributed to the development of molecular marker ACY to aid phenotypic selection. We thus recommend this marker to breeders, which is suitable for marker-assisted selection in tomato.
  19. Md Zali AZ, Ja'afar Y, Paramisparan K, Ismail SI, Saad N, Mohd Hata E, et al.
    Plant Dis, 2022 Jun 24.
    PMID: 35748735 DOI: 10.1094/PDIS-03-22-0650-PDN
    Rice (Oryza sativa) is a staple food for most of the world's populations, particularly in Asia (Gumma et al. 2011). The rice sector provides Malaysians with a food supply, food sufficiency, and income for growers (Man et al. 2009). From January to February 2022, panicle samples showing symptoms of bacterial panicle blight (BPB) disease, including reddish-brown, linear lesions with indistinct margins on flag-leaf sheaths and blighted, upright, grayish straw-colored florets with sterile and aborted grains on panicles were collected in granary areas in Sekinchan, Selangor, Malaysia with 90% disease incidence in fields. Surface-sterilization of infected leaf tissue was performed using 75% ethanol and 1% sodium hypochlorite, followed by rinsing three times in sterilized water. Leaf tissue was macerated in sterilized water and aliquots were spread on King's B agar medium, then cultured for 24 h to 48 h at 35 °C. All isolated bacteria were Gram-negative rods, positive for catalase and gelatinase but negative for indole, oxidase and hydrogen sulfide (H2S), and utilized sucrose, inositol, mannitol, glucose, and citrate. Colonies were circular and smooth-margined, producing a diffusible yellowish-green pigment on King's B agar medium, which are characteristics of Burkholderia species (Keith et al. 2005). Five representative isolates (UPMBG7, UPMBG8, UPMBG9, UPMBG15, UPMBG17) were selected for molecular and pathogenicity tests. PCR using specific primers targeting the gyrB gene for molecular characterization was performed, and the ∼470 bp amplicons were sequenced (Maeda et al. 2006) and deposited in GenBank (OM824438 to OM824442). A BLASTn analysis revealed that the five isolates were 99% identical to the B. gladioli reference strains MAFF 302533, GRBB15041, and LMG19584 in GenBank (AB190628, KX638432, and AB220898). A phylogenetic tree using Maximum-likelihood analysis of the gyrB gene sequences showed that the five isolates were 99% identical to B. gladioli reference strains (AB190628, KX638432, and AB220898). To verify the identification of these isolates, the 16S rDNA gene was amplified using 16SF/16SR primers (Ramachandran et al. 2021), producing ~1,400 bp amplicons. The resulting sequences of the five isolates (OM869953 to OM869957) were 98% identical to the reference strains of B. gladioli (NR113629 and NR117553). To confirm pathogenicity, 10 ml suspensions of the five isolates at of 108 CFU/ml were inoculated into the panicles and crowns of 75-day-old rice seedlings of local rice varieties MR269 and MR219 grown in a glasshouse with temperatures ranging from 37 °C to 41 °C (Nandakumar et al. 2009). Control rice seedlings were inoculated with sterilized water. All isolates produced BPB disease symptoms like those originally found in the rice fields at four weeks after inoculation. Control seedlings remained asymptomatic. To fulfill Koch's postulates, the bacteria were reisolated from symptomatic panicles and were confirmed as B. gladioli by sequence analysis of the gyrB and 16S rDNA genes. To our knowledge, this is the first report of B. gladioli causing BPB disease of rice in Malaysia. Since BPB disease causes a significant threat to the rice industry, it is crucial to investigate the diversity of this destructive pathogen for effective disease management strategies in Malaysia.
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