Displaying publications 441 - 460 of 587 in total

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  1. Chung ELT, Abdullah FFJ, Marza AD, Saleh WMM, Ibrahim HH, Abba Y, et al.
    Microb Pathog, 2017 Jan;102:89-101.
    PMID: 27894962 DOI: 10.1016/j.micpath.2016.11.015
    The aim of this study was to investigate the clinico-pathology and haemato-biochemistry alterations in buffaloes inoculated with Pasteurella multocida type B:2 immunogen outer membrane protein via subcutaneous and oral routes. Nine buffalo heifers were divided equally into 3 treatment groups. Group 1 was inoculated orally with 10 mL of phosphate buffer saline (PBS); Group 2 and 3 were inoculated with 10 mL of outer membrane protein broth subcutaneously and orally respectively. Group 2 buffaloes showed typical haemorrhagic septicaemia clinical signs and were only able to survive for 72 h of the experiment. However, Group 3 buffaloes were able to survive throughout the stipulated time of 21 days of experiment. There were significant differences (p  0.05) in edema between groups except for the lung. This study was a proof that oral route infection of Pasteurella multocida type B:2 immunogen outer membrane protein can be used to stimulate host cell.
    Matched MeSH terms: Phenotype
  2. Kim WJ, Gupta V, Nishimura M, Makita H, Idolor L, Roa C, et al.
    Int J Tuberc Lung Dis, 2018 07 01;22(7):820-826.
    PMID: 29914609 DOI: 10.5588/ijtld.17.0524
    BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a heterogeneous condition that can differ in its clinical manifestation, structural changes and response to treatment.

    OBJECTIVE: To identify subgroups of COPD with distinct phenotypes, evaluate the distribution of phenotypes in four related regions and calculate the 1-year change in lung function and quality of life according to subgroup.

    METHODS: Using clinical characteristics, we performed factor analysis and hierarchical cluster analysis in a cohort of 1676 COPD patients from 13 Asian cities. We compared the 1-year change in forced expiratory volume in one second (FEV1), modified Medical Research Council dyspnoea scale score, St George's Respiratory Questionnaire (SGRQ) score and exacerbations according to subgroup derived from cluster analysis.

    RESULTS: Factor analysis revealed that body mass index, Charlson comorbidity index, SGRQ total score and FEV1 were principal factors. Using these four factors, cluster analysis identified three distinct subgroups with differing disease severity and symptoms. Among the three subgroups, patients in subgroup 2 (severe disease and more symptoms) had the most frequent exacerbations, most rapid FEV1 decline and greatest decline in SGRQ total score.

    CONCLUSION: Three subgroups with differing severities and symptoms were identified in Asian COPD subjects.

    Matched MeSH terms: Phenotype
  3. Ismail NF, Rani AQ, Nik Abdul Malik NM, Boon Hock C, Mohd Azlan SN, Abdul Razak S, et al.
    J Mol Diagn, 2017 03;19(2):265-276.
    PMID: 28087349 DOI: 10.1016/j.jmoldx.2016.10.009
    Tuberous sclerosis complex (TSC) is an autosomal dominant neurocutaneous disorder characterized by tumor growth in multiple organs and caused by mutations in either TSC1 or TSC2 genes. Because of their relatively large genomic sizes, absence of hotspots, and common type of mutations, mutation detection in TSC1 and TSC2 genes has been challenging. We devised a combination of multiple ligation-dependent probe amplification (MLPA) and amplicon sequencing (AS) to simplify the detection strategy, yet we come up with reasonably high detection rate. Thirty-four Malaysian patients diagnosed with TSC were referred to Human Genome Center, Universiti Sains Malaysia. We used a combination of MLPA to detect large copy number changes and AS to detect smaller mutations. TSC1 pathogenic or likely pathogenic mutations were found in 6 patients (18%) and TSC2 in 21 patients (62%), whereas 6 patients (18%) show no mutations and 1 patient (2%) showed only TSC2 missense variant with uncertain significance. Six of the mutations are novel. Our detection strategy costs 81% less and require 1 working week less than the conventional strategy. Confirmatory sequencing using Sanger method on a few representative mutations showed agreement with results of the AS. Combination of MLPA and Illumina MiSeq AS provides a simplified strategy and reasonably high detection rate for TSC1/TSC2 mutation, which suggested application of the strategies into clinical molecular diagnostics.
    Matched MeSH terms: Phenotype
  4. Ang Pei-Shen, Rajesh Ramasamy, Noor Hamidah Hussin, Cheong Soon-Keng, Seow Heng-Fong, Maha Abdullah
    MyJurnal
    Introduction: The phenotype and genotype of cancer cells portray hallmarks of cancer which may
    have clinical value. Cancer cell lines are ideal models to study and confirm these characteristics. We
    previously established two subtracted cDNA libraries with differentially expressed genes from an
    acute myeloid leukaemia patient with poor prognosis (PP) and good prognosis (GP). Objective: To
    compare gene expression of the leukaemia associated genes with selected biological characteristics
    in leukaemia cell lines and normal controls. Methodology: Expression of 28 PP genes associated
    with early fetal/embryonic development, HOX-related genes, hematopoiesis and aerobic glycolysis/
    hypoxia genes and 36 GP genes involved in oxidative phosphorylation, protein synthesis, chromatin
    remodelling and cell motility were examined in B-lymphoid (BV173, Reh and RS4;11) and myeloid
    (HL-60, K562) leukaemia cell lines after 72h in culture as well as peripheral blood mononuclear cells
    from healthy controls (N=5) using semi-quantitative polymerase chain reaction (PCR) method. Cell
    cycle profiles were analysed on flow cytometry while MTT cytotoxicity assay was used to determine
    drug resistance to epirubicin. Results: Genes expressed significantly higher in B-lymphoid leukaemia
    cell lines compared to healthy controls were mostly of the GP library i.e. oxidative phosphorylation
    (3/10), protein synthesis (4/11), chromatin remodelling (3/3) and actin cytoskeleton genes (1/5). Only
    two genes with significant difference were from the PP library. Cancer associated genes, HSPA9 and
    PSPH (GP library) and BCAP31 (PP library) were significantly higher in the B-lymphoid leukemia cell
    lines. No significant difference was observed between myeloid cell lines and healthy controls. This
    may also be due heterogeneity of cell lines studied. PBMC from healthy controls were not in cell cycle.
    G2/M profiles and growth curves showed B-lymphoid cells just reaching plateau after 72 hour culture
    while myeloid cells were declining. IC50 values from cytotoxicity assay revealed myeloid cell lines had
    an average 13-fold higher drug resistance to epirubicin compared to B-lymphoid cell lines. Only CCL1,
    was expressed at least two-fold higher in myeloid compared to B-lymphoid cell lines. In contrast,
    MTRNR2, EEF1A1, PTMA, HLA-DR, C6orf115, PBX3, ENPP4, SELL, and IL3Ra were expressed
    more than 2-fold higher in B-lymphoid compared to myeloid cell lines studied here. Conclusion: Thus,
    B-lymphoid leukaemia cell lines here exhibited active, proliferating characteristics closer to GP genes.
    Higher expression of several genes in B-lymphoid compared to myeloid leukaemia cell lines may be
    useful markers to study biological differences including drug resistance between lineages.
    Matched MeSH terms: Phenotype
  5. Fong MY, Cheong FW, Lau YL
    Parasit Vectors, 2018 Sep 26;11(1):527.
    PMID: 30257710 DOI: 10.1186/s13071-018-3118-8
    BACKGROUND: The merozoite of the zoonotic Plasmodium knowlesi invades human erythrocytes via the binding of its Duffy binding protein (PkDBPαII) to the Duffy antigen on the eythrocytes. The Duffy antigen has two immunologically distinct forms, Fya and Fyb. In this study, the erythrocyte-binding assay was used to quantitatively determine and compare the binding level of PkDBPαII to Fya+/b+ and Fya+/b- human erythrocytes.

    RESULTS: In the erythrocyte-binding assay, binding level was determined by scoring the number of rosettes that were formed by erythrocytes surrounding transfected mammalian COS-7 cells which expressed PkDBPαII. The assay result revealed a significant difference in the binding level. The number of rosettes scored for Fya+/b+ was 1.64-fold higher than that of Fya+/b- (155.50 ± 34.32 and 94.75 ± 23.16 rosettes, respectively; t(6) = -2.935, P = 0.026).

    CONCLUSIONS: The erythrocyte-binding assay provided a simple approach to quantitatively determine the binding level of PkDBPαII to the erythrocyte Duffy antigen. Using this assay, PkDBPαII was found to display higher binding to Fya+/b+ erythrocytes than to Fya+/b- erythrocytes.

    Matched MeSH terms: Phenotype
  6. Tan HT, Hagner S, Ruchti F, Radzikowska U, Tan G, Altunbulakli C, et al.
    Allergy, 2019 02;74(2):294-307.
    PMID: 30267575 DOI: 10.1111/all.13619
    BACKGROUND: Asthma is a chronic respiratory disease with marked clinical and pathophysiological heterogeneity. Specific pathways are thought to be involved in the pathomechanisms of different inflammatory phenotypes of asthma; however, direct in vivo comparison has not been performed.

    METHODS: We developed mouse models representing three different phenotypes of allergic airway inflammation-eosinophilic, mixed, and neutrophilic asthma via different methods of house dust mite sensitization and challenge. Transcriptomic analysis of the lungs, followed by the RT-PCR, western blot, and confocal microscopy, was performed. Primary human bronchial epithelial cells cultured in air-liquid interface were used to study the mechanisms revealed in the in vivo models.

    RESULTS: By whole-genome transcriptome profiling of the lung, we found that airway tight junction (TJ), mucin, and inflammasome-related genes are differentially expressed in these distinct phenotypes. Further analysis of proteins from these families revealed that Zo-1 and Cldn18 were downregulated in all phenotypes, while increased Cldn4 expression was characteristic for neutrophilic airway inflammation. Mucins Clca1 (Gob5) and Muc5ac were upregulated in eosinophilic and even more in neutrophilic phenotype. Increased expression of inflammasome-related molecules such as Nlrp3, Nlrc4, Casp-1, and IL-1β was characteristic for neutrophilic asthma. In addition, we showed that inflammasome/Th17/neutrophilic axis cytokine-IL-1β-may transiently impair epithelial barrier function, while IL-1β and IL-17 increase mucin expressions in primary human bronchial epithelial cells.

    CONCLUSION: Our findings suggest that differential expression of TJ, mucin, and inflammasome-related molecules in distinct inflammatory phenotypes of asthma may be linked to pathophysiology and might reflect the differences observed in the clinic.

    Matched MeSH terms: Phenotype
  7. Loo CH, Tan WC, Tang JJ, Khor YH, Manikam MT, Low DE, et al.
    Int J Dermatol, 2018 Dec;57(12):1454-1463.
    PMID: 30182482 DOI: 10.1111/ijd.14210
    BACKGROUND: Hidradenitis suppurativa (HS) is a chronic, recurrent, inflammatory disorder of follicular occlusion, resulting in abscesses with tunnel formation and severe scarring. Our objectives were to identify the clinical patterns and the prevalence of metabolic syndrome (MetS) among our HS patients and to determine the role of ultrasonography in the clinical assessment of HS.

    METHODS: This was a cross-sectional study carried out from September 2016 to August 2017 at three tertiary hospitals in Northern Peninsular Malaysia.

    RESULTS: A total of 62 patients were recruited, 83.9% of whom were male. The mean age was 29.2 with the median age of onset at 18 years old. The median duration of delay in diagnosis was 3 years. A quarter of them had positive family history. Nearly three-quarters were overweight and obese. About 12/62 (19.4%) had MetS, and it was comparable to healthy controls (15/62, 24.2%). HS patients had a significant higher risk of low-high-density lipoprotein (HDL) and obesity. Based on Hurley staging, 15/62 (24.2%) were in stage I, 38/62 (61.3%) and 9/62 (14.5%) in stages II and III, respectively. However, sonographic scoring showed 50% had severe stage of disease, and 56.9% of the patients had subclinical lesions. There was only a fair agreement between ultrasonography and Hurley staging of disease severity (k = 0.25; P = 0.004).

    CONCLUSION: There was a male preponderance among HS patients in Northern Peninsular Malaysia with early age of onset and more severe disease. Only one-fifth had MetS, but they had significantly higher risks of obesity and low HDL. Ultrasonography examination was useful to detect subclinical lesions and providing a better understanding on disease severity.

    Matched MeSH terms: Phenotype
  8. Cheng CK, Bakar HA, Gollasch M, Huang Y
    Cardiovasc Drugs Ther, 2018 10;32(5):481-502.
    PMID: 30171461 DOI: 10.1007/s10557-018-6820-z
    Perivascular adipose tissue (PVAT) refers to the local aggregate of adipose tissue surrounding the vascular tree, exhibiting phenotypes from white to brown and beige adipocytes. Although PVAT has long been regarded as simply a structural unit providing mechanical support to vasculature, it is now gaining reputation as an integral endocrine/paracrine component, in addition to the well-established modulator endothelium, in regulating vascular tone. Since the discovery of anti-contractile effect of PVAT in 1991, the use of multiple rodent models of reduced amounts of PVAT has revealed its regulatory role in vascular remodeling and cardiovascular implications, including atherosclerosis. PVAT does not only release PVAT-derived relaxing factors (PVRFs) to activate multiple subsets of endothelial and vascular smooth muscle potassium channels and anti-inflammatory signals in the vasculature, but it does also provide an interface for neuron-adipocyte interactions in the vascular wall to regulate arterial vascular tone. In this review, we outline our current understanding towards PVAT and attempt to provide hints about future studies that can sharpen the therapeutic potential of PVAT against cardiovascular diseases and their complications.
    Matched MeSH terms: Phenotype
  9. Tay CG, Fong CY, Li L, Ganesan V, Teh CM, Gan CS, et al.
    J Clin Neurosci, 2020 Feb;72:468-471.
    PMID: 31831253 DOI: 10.1016/j.jocn.2019.12.007
    Congenital myasthenic syndrome (CMS) is a heterogeneous group of inherited disorder which does not associate with anti-acetylcholine receptor (AChR) antibody. The presence of AChR autoantibody is pathogenic and highly sensitive and specific for autoimmune myasthenia gravis (MG). We describe 2 children from unrelated families who presented with hypotonia, ptosis and fatigability in early infancy with anti-AChR antibodies detected via ELISA on 2 separate occasions in the sera. Both were treated as refractory autoimmune MG due to poor clinical response to acetylcholinesterase inhibitor and immunotherapy. In view of the atypical clinical features, genetic studies of CMS were performed and both were confirmed to have novel pathogenic mutations in the COLQ gene. To the best of our knowledge, the presence of anti-AChR antibody in COLQ-related CMS has never been reported in the literature. The clinical presentation of early onset phenotype, and refractoriness to acetylcholinesterase inhibitor and immunotherapy should prompt CMS as a differential diagnosis.
    Matched MeSH terms: Phenotype
  10. Ma B, Khazali A, Shao H, Jiang Y, Wells A
    Cell Commun Signal, 2019 12 12;17(1):164.
    PMID: 31831069 DOI: 10.1186/s12964-019-0489-1
    BACKGROUND: Carcinoma cells shift between epithelial and mesenchymal phenotypes during cancer progression, as defined by surface presentation of the cell-cell cohesion molecule E-cadherin, affecting dissemination, progression and therapy responsiveness. Concomitant with the loss of E-cadherin during the mesenchymal transition, the predominant receptor isoform for ELR-negative CXC ligands shifts from CXCR3-B to CXCR3-A which turns this classical G-protein coupled receptor from an inhibitor to an activator of cell migration, thus promoting tumor cell invasiveness. We proposed that CXCR3 was not just a coordinately changed receptor but actually a regulator of the cell phenotype.

    METHODS: Immunoblotting, immunofluorescence, quantitative real-time PCR and flow cytometry assays investigated the expression of E-cadherin and CXCR3 isoforms. Intrasplenic inoculation of human prostate cancer (PCa) cells with spontaneous metastasis to the liver analyzed E-cadherin and CXCR3-B expression during cancer progression in vivo.

    RESULTS: We found reciprocal regulation of E-cadherin and CXCR3 isoforms. E-cadherin surface expression promoted CXCR3-B presentation on the cell membrane, and to a lesser extent increased its mRNA and total protein levels. In turn, forced expression of CXCR3-A reduced E-cadherin expression level, whereas CXCR3-B increased E-cadherin in PCa. Meanwhile, a positive correlation of E-cadherin and CXCR3-B expression was found both in experimental PCa liver micro-metastases and patients' tissue.

    CONCLUSIONS: CXCR3-B and E-cadherin positively correlated in vitro and in vivo in PCa cells and liver metastases, whereas CXCR3-A negatively regulated E-cadherin expression. These results suggest that CXCR3 isoforms may play important roles in cancer progression and dissemination via diametrically regulating tumor's phenotype.

    Matched MeSH terms: Phenotype
  11. Williams M, Valayannopoulos V, Altassan R, Chung WK, Heijboer AC, Keng WT, et al.
    J Inherit Metab Dis, 2019 01;42(1):147-158.
    PMID: 30740741 DOI: 10.1002/jimd.12036
    BACKGROUND: Transaldolase deficiency (TALDO-D) is a rare autosomal recessive inborn error of the pentose phosphate pathway. Since its first description in 2001, several case reports have been published, but there has been no comprehensive overview of phenotype, genotype, and phenotype-genotype correlation.

    METHODS: We performed a retrospective questionnaire and literature study of clinical, biochemical, and molecular data of 34 patients from 25 families with proven TALDO-D. In some patients, endocrine abnormalities have been found. To further evaluate these abnormalities, we performed biochemical investigations on blood of 14 patients.

    RESULTS AND CONCLUSIONS: Most patients (n = 22) had an early-onset presentation (prenatally or before 1 month of age); 12 patients had a late-onset presentation (3 months to 9 years). Main presenting symptoms were intrauterine growth restriction, dysmorphic facial features, congenital heart disease, anemia, thrombocytopenia, and hepato(spleno)megaly. An older sib of two affected patients was asymptomatic until the age of 9 years, and only after molecular diagnosis was hepatomegaly noted. In some patients, there was gonadal dysfunction with low levels of testosterone and secondary luteinizing hormone (LH) and follicle-stimulating hormone (FSH) abnormalities later in life. This overview provides information that can be helpful for managing patients and counseling families regarding prognosis. Diagnostic guidelines, possible genotype-phenotype correlations, treatment options, and pathophysiological disease mechanisms are proposed.

    Matched MeSH terms: Phenotype
  12. Ripen AM, Chiow MY, Rama Rao PR, Mohamad SB
    Front Immunol, 2021;12:778133.
    PMID: 34804071 DOI: 10.3389/fimmu.2021.778133
    Blended phenotypes exhibited by a patient may present a challenge to the establishment of diagnosis. In this study, we report a seven-year-old Murut girl with unusual features of Williams-Beuren syndrome (WBS), including recurrent infections and skin abscesses. Considering the possibility of a second genetic disorder, a mutation screening for genes associated with inborn errors of immunity (IEI) was conducted using whole exome sequencing (WES). Analysis of copy number variations (CNVs) from the exome data revealed a 1.53Mb heterozygous deletion on chromosome 7q11.23, corresponding to the known WBS. We also identified a biallelic loss of NCF1, which indicated autosomal recessive chronic granulomatous disease (CGD). Dihydrorhodamine (DHR) flow cytometric assay demonstrated abnormally low neutrophil oxidative burst activity. Coamplification of NCF1 and its pseudogenes identified a GT-deletion (ΔGT) at the start of exon 2 in NCF1 (NM_000265.7: c.75_76delGT: p.Tyr26Hisfs*26). Estimation of NCF1-to-NCF1 pseudogenes ratio using ΔGT and 20-bp gene scans affirmed nil copies of NCF1 in the patient. While the father had a normal ratio of 2:4, the mother had a ratio of 1:5, implicating the carrier of ΔGT-containing NCF1. Discovery of a 7q11.23 deletion involving one NCF1 allele and a ΔGT in the second NCF1 allele explained the coexistence of WBS and CGD in our patient. This study highlights the capability of WES to establish a molecular diagnosis for a case with blended phenotypes, enabling the provision of appropriate prophylactic treatment.
    Matched MeSH terms: Phenotype
  13. Hawkins BR, Simons MJ, Goh EH, Chia KB, Shanmugaratnam K
    Int J Cancer, 1974 Jan 15;13(1):116-21.
    PMID: 4206461 DOI: 10.1002/ijc.2910130113
    Matched MeSH terms: Phenotype
  14. Basri NI, Soon CH, Ali A, Abdul Ghani NA, Zainuddin AA
    Horm Mol Biol Clin Investig, 2021 Mar 08;42(3):325-328.
    PMID: 33675193 DOI: 10.1515/hmbci-2021-0001
    OBJECTIVES: We compared cases of phenotypic female patients who presented with male karyotype and underwent prophylactic gonadectomy.

    CASE PRESENTATION: Five patients with female phenotypes presented in early adulthood with primary amenorrhoea with varying degrees of puberty. One was tall with breast development. Another was very short with clitoromegaly and multiple co-morbidities. The other three had no secondary sexual characteristics. They were examined, after which hormonal profile, karyotyping, ultrasound examination and magnetic resonance imaging were done to assess the site of gonads. Gonadectomy was performed once their 46 XY karyotype was confirmed. Results of histopathological examination of their gonads ranged from dysgenetic gonads to having testicular tissues and malignancy.

    CONCLUSION: Female patients with 46 XY karyotypes require prophylactic gonadectomy performed at different timings depending on diagnosis due to the malignancy risk. Pre-operative assessment is essential to locate the gonads prior to surgery.

    Matched MeSH terms: Phenotype
  15. van Prooije T, Ibrahim NM, Azmin S, van de Warrenburg B
    Parkinsonism Relat Disord, 2021 11;92:112-118.
    PMID: 34711523 DOI: 10.1016/j.parkreldis.2021.10.023
    This paper reviews and summarizes three main aspects of spinocerebellar ataxias (SCA) in the Asian population. First, epidemiological studies were comprehensively reviewed. Overall, the most common subtypes include SCA1, SCA2, SCA3, and SCA6, but there are large differences in the relative prevalence of these and other SCA subtypes between Asian countries. Some subtypes such as SCA12 and SCA31 are rather specific to certain Asian populations. Second, we summarized distinctive phenotypic manifestations of SCA patients of Asian origin, for example a frequent co-occurrence of parkinsonism in some SCA subtypes. Lastly, we have conducted an exploratory survey study to map SCA-specific expertise, resources, and management in various Asian countries. This showed large differences in accessibility, genetic testing facilities, and treatment options between lower and higher income Asian countries. Currently, many Asian SCA patients remain without a final genetic diagnosis. Lack of prevalence data on SCA, lack of patient registries, and insufficient access to genetic testing facilities hamper a wider understanding of these diseases in several (particularly lower income) Asian countries.
    Matched MeSH terms: Phenotype
  16. Goh LL, Lim CW, Sim WC, Toh LX, Leong KP
    PLoS One, 2017;12(1):e0169233.
    PMID: 28046094 DOI: 10.1371/journal.pone.0169233
    BACKGROUND: Genetic determinants of drug response remain stable throughout life and offer great promise to patient-tailored drug therapy. The adoption of pharmacogenetic (PGx) testing in patient care requires accurate, cost effective and rapid genotyping with clear guidance on the use of the results. Hence, we evaluated a 32 SNPs panel for implementing PGx testing in clinical laboratories.

    METHODS: We designed a 32-SNP panel for PGx testing in clinical laboratories. The variants were selected using the clinical annotations of the Pharmacogenomics Knowledgebase (PharmGKB) and include polymorphisms of CYP2C9, CYP2C19, CYP2D6, CYP3A5 and VKORC1 genes. The CYP2D6 gene allele quantification was determined simultaneously with TaqMan copy number assays targeting intron 2 and exon 9 regions. The genotyping results showed high call rate accuracy according to concordance with genotypes identified by independent analyses on Sequenome massarray and droplet digital PCR. Furthermore, 506 genomic samples across three major ethnic groups of Singapore (Malay, Indian and Chinese) were analysed on our workflow.

    RESULTS: We found that 98% of our study subjects carry one or more CPIC actionable variants. The major alleles detected include CYP2C9*3, CYP2C19*2, CYP2D6*10, CYP2D6*36, CYP2D6*41, CYP3A5*3 and VKORC1*2. These translate into a high percentage of intermediate (IM) and poor metabolizer (PM) phenotypes for these genes in our population.

    CONCLUSION: Genotyping may be useful to identify patients who are prone to drug toxicity with standard doses of drug therapy in our population. The simplicity and robustness of this PGx panel is highly suitable for use in a clinical laboratory.

    Matched MeSH terms: Phenotype
  17. Zaw MT, Emran NA, Ibrahim MY, Suleiman M, Awang Mohd TA, Yusuff AS, et al.
    J Microbiol Immunol Infect, 2019 Aug;52(4):563-570.
    PMID: 29428381 DOI: 10.1016/j.jmii.2018.01.003
    BACKGROUND: Cholera is an important health problem in Sabah, a Malaysian state in northern Borneo; however, Vibrio cholerae in Sabah have never been characterized. Since 2002, serogroup O1 strains having the traits of both classical and El Tor biotype, designated as atypical El Tor biotype, have been increasingly reported as the cause of cholera worldwide. These variants are believed to produce clinically more severe disease like classical strains.

    PURPOSE: The purpose of this study is to investigate the genetic diversity of V.cholerae in Sabah and whether V.cholerae in Sabah belong to atypical El Tor biotype.

    METHODS: ERIC-PCR, a DNA fingerprinting method for bacterial pathogens based on the enterobacterial repetitive intergenic consensus sequence, was used to study the genetic diversity of 65 clinical V.cholerae O1 isolates from 3 districts (Kudat, Beluran, Sandakan) in Sabah and one environmental isolate from coastal sea water in Kudat district. In addition, we studied the biotype-specific genetic traits in these isolates to establish their biotype.

    RESULTS: Different fingerprint patterns were seen in isolates from these three districts but one of the patterns was seen in more than one district. Clinical isolates and environmental isolate have different patterns. In addition, Sabah isolates harbor genetic traits specific to both classical biotype (ctxB-1, rstRCla) and El Tor biotype (rstRET, rstC, tcpAET, rtxC, VC2346).

    CONCLUSION: This study revealed that V.cholerae in Sabah were genetically diverse and were atypical El Tor strains. Fingerprint patterns of these isolates will be useful in tracing the origin of this pathogen in the future.

    Matched MeSH terms: Phenotype
  18. van Velzen R, Holmer R, Bu F, Rutten L, van Zeijl A, Liu W, et al.
    Proc Natl Acad Sci U S A, 2018 May 15;115(20):E4700-E4709.
    PMID: 29717040 DOI: 10.1073/pnas.1721395115
    Nodules harboring nitrogen-fixing rhizobia are a well-known trait of legumes, but nodules also occur in other plant lineages, with rhizobia or the actinomycete Frankia as microsymbiont. It is generally assumed that nodulation evolved independently multiple times. However, molecular-genetic support for this hypothesis is lacking, as the genetic changes underlying nodule evolution remain elusive. We conducted genetic and comparative genomics studies by using Parasponia species (Cannabaceae), the only nonlegumes that can establish nitrogen-fixing nodules with rhizobium. Intergeneric crosses between Parasponia andersonii and its nonnodulating relative Trema tomentosa demonstrated that nodule organogenesis, but not intracellular infection, is a dominant genetic trait. Comparative transcriptomics of P. andersonii and the legume Medicago truncatula revealed utilization of at least 290 orthologous symbiosis genes in nodules. Among these are key genes that, in legumes, are essential for nodulation, including NODULE INCEPTION (NIN) and RHIZOBIUM-DIRECTED POLAR GROWTH (RPG). Comparative analysis of genomes from three Parasponia species and related nonnodulating plant species show evidence of parallel loss in nonnodulating species of putative orthologs of NIN, RPG, and NOD FACTOR PERCEPTION Parallel loss of these symbiosis genes indicates that these nonnodulating lineages lost the potential to nodulate. Taken together, our results challenge the view that nodulation evolved in parallel and raises the possibility that nodulation originated ∼100 Mya in a common ancestor of all nodulating plant species, but was subsequently lost in many descendant lineages. This will have profound implications for translational approaches aimed at engineering nitrogen-fixing nodules in crop plants.
    Matched MeSH terms: Phenotype
  19. Chen CH, Shimada T, Elhadi N, Radu S, Nishibuchi M
    Appl Environ Microbiol, 2004 Apr;70(4):1964-72.
    PMID: 15066786
    Of 97 strains of Vibrio cholerae isolated from various seafoods in Malaysia in 1998 and 1999, 20 strains carried the ctx gene and produced cholera toxin. Fourteen, one, and five of these toxigenic strains belonged to the O139, O1 Ogawa, and rough serotypes, respectively. The rough strains had the rfb gene of the O1 serotype. The toxigenic strains varied in their biochemical characteristics, the amount of cholera toxin produced, their antibiograms, and the presence or absence of the pTLC plasmid sequence. DNA fingerprinting analysis by arbitrarily primed PCR, ribotyping, and a pulsed-field gel electrophoresis method classified the toxigenic strains into 3, 7, and 10 types, respectively. The relatedness of these toxigenic strains to clinical strains isolated in other countries and from international travelers was examined by using a dendrogram constructed from the pulsed-field gel electrophoresis profiles. The results of the examination of the antibiogram and the possession of the toxin-linked cryptic plasmid were consistent with the dendrogram-based relatedness: the O139 strains isolated from Malaysian seafoods could be separated into two groups that appear to have been introduced from the Bengal area independently. The rough strains of Malaysian seafood origin formed one group and belonged to a cluster unique to the Thailand-Malaysia-Laos region, and this group may have persisted in this area for a long period. The single O1 Ogawa strain detected in Malaysian seafood appears to have an origin and route of introduction different from those of the O139 and the rough strains.
    Matched MeSH terms: Phenotype
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