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Fulltext Stem cell heterogeneity of mononucleated cells from murine peripheral blood: molecular analysis

Yazid MD, Zainal Ariffin SH, Senafi S, Zainal Ariffin Z, Megat Abdul Wahab R

ScientificWorldJournal, 2011;11:2150-9.
PMID: 22125464 DOI: 10.1100/2011/340278

The main purpose of this paper was to determine the heterogeneity of primary isolated mononucleated cells that originated from the peripheral blood system by observing molecular markers. The isolated cells were cultured in complete medium for 4 to 7 days prior to the separation of different cell types, that is, adherent and suspension. Following a total culture time of 14 days, adherent cells activated the Cd105 gene while suspension cells activated the Sca-1 gene. Both progenitor markers, Cbfa-1 and Ostf-1, were inactivated in both suspension and adherent cells after 14-day culture compared to cells cultured 3 days in designated differentiation medium. In conclusion, molecular analyses showed that primary mononucleated cells are heterogeneous, consisting of hematopoietic stem cells (suspension) and mesenchymal stem cells (adherent) while both cells contained no progenitor cells.

Matched MeSH terms: Antigens, Ly/genetics; Membrane Proteins/genetics; Intracellular Signaling Peptides and Proteins/genetics
Unleashing Breast Cancer Progression: miR-455-5p's Targeting of SOCS3 Drives Proliferation, Migration, and Invasion

Li X, Peng B, Li J, Tian M, He L

Protein Pept Lett, 2023;30(12):992-1000.
PMID: 38013437 DOI: 10.2174/0109298665245603231106050224

OBJECTIVES: We aim to investigate the regulatory mechanisms of miR-455-5p/SOCS3 pathway that underlie the proliferation, migration, and invasion of triple-negative breast cancer (TNBC) cells.
METHODS: Reverse transcription-quantitative PCR (RT-qPCR) was used to detect miR-455-5p expression in breast cancer tissues and cell lines. CCK8 and Transwell assays were conducted to assess the effects of miR-455-5p on breast cancer line proliferation, migration, and invasion. SOCS3 expression level in breast cancer tissues and cell lines was determined by qPCR and western blotting. The targeting relationship between miR-455-5p and SOCS3 was determined by dual luciferase reporter gene assay in different breast cancer cell lines. Finally, the upstream and downstream regulatory association between miR-455-5p and SOCS3 was confirmed in breast cancer cells by CCK8, western blot, and Transwell assays.
RESULTS: MiR-455-5p expression was up-regulated in breast cancer tissues; miR-455-5p regulates TNBC proliferation, migration, and invasion of TNBC. SOCS3 was the direct target of miR-455-5p and was down-regulated in breast cancer. Interference with SOCS3 reversed the inhibitory effect of the miR-455-5p inhibitor on breast cancer cells' malignant potential.
CONCLUSION: MiR-455-5p promotes breast cancer progression by targeting the SOCS3 pathway and may be a potential therapeutic target for breast cancer.

Matched MeSH terms: Cell Movement/genetics; Cell Proliferation/genetics; Suppressor of Cytokine Signaling 3 Protein/genetics
Integrative analysis of chloroplast DNA methylation in a marine alga-Saccharina japonica

Teng L, Han W, Fan X, Zhang X, Xu D, Wang Y, et al.

Plant Mol Biol, 2021 Apr;105(6):611-623.
PMID: 33528753 DOI: 10.1007/s11103-020-01113-9

We applied an integrative approach using multiple methods to verify cytosine methylation in the chloroplast DNA of the multicellular brown alga Saccharina japonica. Cytosine DNA methylation is a heritable process which plays important roles in regulating development throughout the life cycle of an organism. Although methylation of nuclear DNA has been studied extensively, little is known about the state and role of DNA methylation in chloroplast genomes, especially in marine algae. Here, we have applied an integrated approach encompassing whole-genome bisulfite sequencing, methylated DNA immunoprecipitation, gene co-expression networks and photophysiological analyses to provide evidence for the role of chloroplast DNA methylation in a marine alga, the multicellular brown alga Saccharina japonica. Although the overall methylation level was relatively low in the chloroplast genome of S. japonica, gametophytes exhibited higher methylation levels than sporophytes. Gene-specific bisulfite-cloning sequencing provided additional evidence for the methylation of key photosynthetic genes. Many of them were highly expressed in sporophytes whereas genes involved in transcription, translation and biosynthesis were strongly expressed in gametophytes. Nucleus-encoded photosynthesis genes were co-expressed with their chloroplast-encoded counterparts potentially contributing to the higher photosynthetic performance in sporophytes compared to gametophytes where these co-expression networks were less pronounced. A nucleus-encoded DNA methyltransferase of the DNMT2 family is assumed to be responsible for the methylation of the chloroplast genome because it is predicted to possess a plastid transit peptide.

Matched MeSH terms: Phaeophyta/genetics*; Chloroplasts/genetics; DNA, Chloroplast/genetics*
Nine different glucose-6-phosphate dehydrogenase (G6PD) variants in a Malaysian population with Malay, Chinese, Indian and Orang Asli (aboriginal Malaysian) backgrounds

Wang J, Luo E, Hirai M, Arai M, Abdul-Manan E, Mohamed-Isa Z, et al.

Acta Med Okayama, 2008 Oct;62(5):327-32.
PMID: 18985093

The Malaysian people consist of several ethnic groups including the Malay, the Chinese, the Indian and the Orang Asli (aboriginal Malaysians). We collected blood samples from outpatients of 2 hospitals in the State of Selangor and identified 27 glucose-6-phosphate dehydrogenase (G6PD)-deficient subjects among these ethnic groups. In the Malay, G6PD Viangchan (871GA, 1311CT, IVS11 nt93TC) and G6PD Mahidol (487GA) types, which are common in Cambodia and Myanmar, respectively, were detected. The Malay also had both subtypes of G6PD Mediterranean:the Mediterranean subtype (563CT, 1311CT, IVS11 nt93TC) and the Indo-Pakistan subtype (563CT, 1311C, IVS11 nt93T). In Malaysians of Chinese background, G6PD Kaiping (1388GA), G6PD Canton (1376GT) and G6PD Gaohe (95AG), which are common in China, were detected. Indian Malaysians possessed G6PD Mediterranean (Indo-Pakistan subtype) and G6PD Namoru (208TC), a few cases of which had been reported in Vanuatu and many in India. Our findings indicate that G6PD Namoru occurs in India and flows to Malaysia up to Vanuatu. We also discovered 5 G6PD-deficient cases with 2 nucleotide substitutions of 1311CT and IVS11 nt93TC, but without amino-acid substitution in the G6PD molecule. These results indicate that the Malaysian people have incorporated many ancestors in terms of G6PD variants.

Matched MeSH terms: Glucosephosphate Dehydrogenase/genetics*; Glucosephosphate Dehydrogenase Deficiency/genetics*; Genetic Variation/genetics*
Genetic study of the Paleolithic and Neolithic Southeast Asians

Oota H, Kurosaki K, Pookajorn S, Ishida T, Ueda S

Hum Biol, 2001 Apr;73(2):225-31.
PMID: 11446426

DNA samples were extracted from six prehistoric human remains, found on the Malay Peninsula, dating to the Paleolithic and the Neolithic periods. Nucleotide sequences of mitochondrial DNA were determined by the polymerase chain reaction-direct sequencing method. A phylogenetic tree between prehistoric and present humans was constructed based on the nucleotide sequence data. Mitochondrial DNA phylogenetic relationships and ethnoarchaeological evidence suggest that there is a continuity beetween the pre-Neolithic humans and the present Semang and that the Neolithic humans in this area might be an ancestral group of the Senoi.

Matched MeSH terms: Genetics, Population*; Asian Continental Ancestry Group/genetics*
Why have the peninsular "negritos" remained distinct?

Benjamin G

Hum Biol, 2013 Feb-Jun;85(1-3):445-84.
PMID: 24297237

The primary focus of this article is on the so-called negritos of Peninsular Malaysia and southern Thailand, but attention is also paid to other parts of Southeast Asia. I present a survey of current views on the "negrito" phenotype--is it single or many? If the phenotype is many (as now seems likely), it must have resulted from parallel evolution in the several different regions where it has been claimed to exist. This would suggest (contrary to certain views that have been expressed on the basis of very partial genetic data) that the phenotype originated recently and by biologically well-authenticated processes from within the neighboring populations. Whole-genome and physical-anthropological research currently support this view. Regardless of whether the negrito phenotype is ancient or recent-and to the extent that it retains any valid biological reality (which is worth questioning)-explanations are still needed for its continued distinctiveness. In the Malay Peninsula, a distinctive "Semang" societal pattern followed by most, but not all, so-called negritos may have been responsible for this by shaping familial, breeding, and demographic patterns to suit the two main modes of environmental appropriation that they have followed, probably for some millennia: nomadic foraging in the forest, and facultative dependence on exchange or labor relations with neighboring populations. The known distribution of "negritos" in the Malay Peninsula is limited to areas within relatively easy reach of archaeologically authenticated premodern transpeninsular trading and portage routes, as well as of other non-negrito, Aslian-speaking populations engaged in swidden farming. This suggests that their continued distinctiveness has resulted from a wish to maintain a complementary advantage vis-à-vis other, less specialized populations. Nevertheless, a significant degree of discordance exists between the associated linguistic, societal-tradition, and biological patterns which suggests that other factors have also been at play.

Matched MeSH terms: Genetics, Population*; Asian Continental Ancestry Group/genetics*
Admixture patterns and genetic differentiation in negrito groups from West Malaysia estimated from genome-wide SNP data

Jinam TA, Phipps ME, Saitou N, Hugo Pan-Asian SNP Consortium

Hum Biol, 2013 Feb-Jun;85(1-3):173-88.
PMID: 24297225

Southeast Asia houses various culturally and linguistically diverse ethnic groups. In Malaysia, where the Malay, Chinese, and Indian ethnic groups form the majority, there exist minority groups such as the "negritos" who are believed to be descendants of the earliest settlers of Southeast Asia. Here we report patterns of genetic substructure and admixture in two Malaysian negrito populations (Jehai and Kensiu), using ~50,000 genome-wide single-nucleotide polymorphism (SNP) data. We found traces of recent admixture in both the negrito populations, particularly in the Jehai, with the Malay through principal component analysis and STRUCTURE analysis software, which suggested that the admixture was as recent as one generation ago. We also identified significantly differentiated nonsynonymous SNPs and haplotype blocks related to intracellular transport, metabolic processes, and detection of stimulus. These results highlight the different levels of admixture experienced by the two Malaysian negritos. Delineating admixture and differentiated genomic regions should be of importance in designing and interpretation of molecular anthropology and disease association studies.

Matched MeSH terms: Genetics, Population*; Asian Continental Ancestry Group/genetics*
Molecular analysis of vibrio cholerae strains isolated in Malaysia: public health implications

Iyer L, Vadivelu J

Asia Pac J Public Health, 2006;18(3):33-41.
PMID: 17153080

The genetic diversity or clonality among Vibrio cholerae O1, O139 and non-O1/ non-O139 of clinical and environmental origin using ribotyping and PFGE was performed in order to ascertain the public health implications of the different genotypes circulating within the Malaysian environment. Using an in-house typing scheme, of the 214 strains included, 202 strains were isolated locally between 1992 and 1998, seven were obtained from Bangladesh and five were reference strains. Amongst the 176 El Tor O1 strains, 152 clinical strains demonstrated five ribotypes--E1a, E1b, E2a, E3 and E1c. E1b was the most predominant ribotype demonstrated by 84% of the El Tor O1 strains and was present in all years demonstrating that this strain was intrinsic to Malaysia. PFGE analysis of these strains demonstrated minimal variation amongst the 15 PFGE profiles obtained. Ribotpye E2a amongst five clinical and two environmental O1 strains, were from one location and had previously been reported in Indonesia and the Philippines, thus demonstrating strong evidence that these strains may have been imported into Malaysia. Among Vibrio cholerae O139 strains, 91.7% were of ribotype A1a similar to the original O139, while two others were of ribotype A1b and one of A1e, corresponding to ribotypes 1, 2 and 3 of Dalsgaard and colleagues' scheme for O139 strains. PFGE analysis demonstrated that 89% of ribotype A1a could be differentiated into three PFGE genotypes which were very closely related. The eight non-O1/non-O139 serogroup strains were heterogeneous in both ribotype and PFGE patterns.

Matched MeSH terms: DNA, Bacterial/genetics; RNA, Ribosomal/genetics; Vibrio cholerae/genetics*
A comparison of the VP1, VP2, and VP4 regions for molecular typing of human enteroviruses

Perera D, Shimizu H, Yoshida H, Tu PV, Ishiko H, McMinn PC, et al.

J Med Virol, 2010 Apr;82(4):649-57.
PMID: 20166171 DOI: 10.1002/jmv.21652

The VP4, VP2, and VP1 gene regions were evaluated for their usefulness in typing human enteroviruses. Three published RT-PCR primers sets targeting separately these three gene regions were used. Initially, from a total of 86 field isolates (36 HEV-A, 40 HEV-B, and 10 HEV-C) tested, 100% concordance in HEV-A was identified from all three gene regions (VP4, VP2, and VP1). However, for HEV-B and HEV-C viruses, only the VP2 and VP1 regions, and not VP4, showed 100% concordance in typing these viruses. To evaluate further the usefulness of VP4 in typing HEV-A enteroviruses, 55 Japanese and 203 published paired VP4 and VP1 nucleotide sequences were also examined. In each case, typing by VP4 was 100% in concordance with typing using VP1. Given these results, it is proposed that for HEV-A enteroviruses, all three gene regions (VP4, VP2, and VP1), would be useful for typing these viruses. These options would enhance the capability of laboratories in identifying these viruses and would greatly help in outbreaks of hand, foot, and mouth disease.

Matched MeSH terms: Enterovirus/genetics*; Viral Structural Proteins/genetics*; DNA Primers/genetics
Fulltext Human TGF-β1 deficiency causes severe inflammatory bowel disease and encephalopathy

Kotlarz D, Marquardt B, Barøy T, Lee WS, Konnikova L, Hollizeck S, et al.

Nat Genet, 2018 Mar;50(3):344-348.
PMID: 29483653 DOI: 10.1038/s41588-018-0063-6

Transforming growth factor (TGF)-β1 (encoded by TGFB1) is the prototypic member of the TGF-β family of 33 proteins that orchestrate embryogenesis, development and tissue homeostasis1,2. Following its discovery 3 , enormous interest and numerous controversies have emerged about the role of TGF-β in coordinating the balance of pro- and anti-oncogenic properties4,5, pro- and anti-inflammatory effects 6 , or pro- and anti-fibrinogenic characteristics 7 . Here we describe three individuals from two pedigrees with biallelic loss-of-function mutations in the TGFB1 gene who presented with severe infantile inflammatory bowel disease (IBD) and central nervous system (CNS) disease associated with epilepsy, brain atrophy and posterior leukoencephalopathy. The proteins encoded by the mutated TGFB1 alleles were characterized by impaired secretion, function or stability of the TGF-β1-LAP complex, which is suggestive of perturbed bioavailability of TGF-β1. Our study shows that TGF-β1 has a critical and nonredundant role in the development and homeostasis of intestinal immunity and the CNS in humans.

Matched MeSH terms: Brain Diseases/genetics*; Inflammatory Bowel Diseases/genetics*; Transforming Growth Factor beta1/genetics*
Acid alpha-glucosidase in Malaysians. Population studies and the occurrence of a new variant

Teng YS, Tan SG

Hum Hered, 1979;29(1):2-4.
PMID: 367946

Acid alpha-glucosidase from the placenta was electrophoretically surveyed in a total of 633 Malaysians, 236 of Malay, 261 of Chinese and 136 of Indian ancestries. A new variant, alpha-glucosidase 3-1 was observed in 1 Malay and 3 Indians. A polymorphism for this enzyme was observed among Indians, but in Chinese and Malays variants are rare. Phenotype 2-1 was observed once in a Chinese and once in a Malay.

Matched MeSH terms: alpha-Glucosidases/genetics*; Glucosidases/genetics*; Isoenzymes/genetics*
HLA-DQ alpha genotype and allele frequencies in Malays, Chinese, and Indians in the Malaysian population

Koh CL, Benjamin DG

Hum Hered, 1994 May-Jun;44(3):150-5.
PMID: 8039798

The HLA-DQ alpha genotype and allele frequencies in 130 Malays, 125 Chinese, and 137 Indians in the Malaysian population were determined using a commercial HLA-DQ alpha DNA amplification and typing kit which distinguishes 6 alleles (DQA1.1, DQA1.2, DQA1.3, DQA2, DQA3, and DQA4) and 21 possible genotypes at this locus. All 21 genotypes were encountered in the Malay and Indian samples, but DQA1.1,DQA1.3 and DQA2,DQA2 genotypes were absent in the Chinese sample. In all three ethnic groups, the numbers observed for the various DQ alpha genotypes were in accordance with those expected from Hardy-Weinberg equilibrium. The allele frequencies observed in these three groups were significantly different to allow them to be distinguished as distinct populations. For the Malays, Chinese, and Indians, heterozygosity values at this locus were 0.77, 0.77, and 0.83, respectively, and values of the power of discrimination were 0.91, 0.90, and 0.94, respectively. These population data will enable the HLA-DQ alpha locus to be used as a marker in forensic identity testing in Malaysia.

Matched MeSH terms: Ethnic Groups/genetics; Gene Frequency/genetics*; HLA-DQ Antigens/genetics*
Apolipoprotein A-IV polymorphism in Singapore ethnic groups

Saha N

Hum Hered, 1991;41(1):47-52.
PMID: 2050382

A total of 627 subjects comprising 455 Chinese, 127 Dravidian Indians and 45 Malays were investigated for serum Apo A-IV polymorphism. The frequency of Apo A-IV*2 was found to be significantly higher (p less than 0.001) in Indians (0.043) compared to that in the Chinese (0.010) and Malays (0.011). The frequency of A-IV*3 was found to be around 0.02 in all the ethnic groups. A low frequency of A-IV*4 (less than 0.01) was observed in the Chinese and Indians. The phenotypic distribution of Apo A-IV was at Hardy-Weinberg equilibrium in the three ethnic groups.

Matched MeSH terms: Apolipoproteins A/genetics*; European Continental Ancestry Group/genetics; Asian Continental Ancestry Group/genetics
Fulltext Utilization of Small RNA Genes to Distinguish Vibrio cholerae Biotypes via Multiplex Polymerase Chain Reaction

Ahmed SA, Raabe CA, Cheah HL, Hoe CH, Rozhdestvensky TS, Tang TH

Am J Trop Med Hyg, 2019 Jun;100(6):1328-1334.
PMID: 30963989 DOI: 10.4269/ajtmh.18-0525

The diarrheal disease "cholera" is caused by Vibrio cholerae, and is primarily confined to endemic regions, mostly in Africa and Asia. It is punctuated by outbreaks and creates severe challenges to public health. The disease-causing strains are most-often members of serogroups O1 and O139. PCR-based methods allow rapid diagnosis of these pathogens, including the identification of their biotypes. However, this necessitates the selection of specific target sequences to differentiate even the closely related biotypes of V. cholerae. Oligonucleotides for selective amplification of small RNA (sRNA) genes that are specific to these V. cholerae subtypes were designed. The resulting multiplex PCR assay was validated using V. cholerae cultures (i.e., 19 V. cholerae and 22 non-V. cholerae isolates) and spiked stool samples. The validation using V. cholerae cultures and spiked stool suspensions revealed detection limits of 10-100 pg DNA per reaction and 1.5 cells/mL suspension, respectively. The multiplex PCR assay that targets sRNA genes for amplification enables the sensitive and specific detection, as well as the differentiation of V. cholerae-O1 classical, O1 El Tor, and O139 biotypes. Most importantly, the assay enables fast and cheaper diagnosis compared with classic culture-based methods.

Matched MeSH terms: DNA, Bacterial/genetics; RNA, Bacterial/genetics*; Vibrio cholerae/genetics*
Fulltext Laboratory-Based Surveillance and Molecular Characterization of Dengue Viruses in Taiwan, 2014

Chang SF, Yang CF, Hsu TC, Su CL, Lin CC, Shu PY

Am J Trop Med Hyg, 2016 Apr;94(4):804-11.
PMID: 26880779 DOI: 10.4269/ajtmh.15-0534

We present the results of a laboratory-based surveillance of dengue in Taiwan in 2014. A total of 240 imported dengue cases were identified. The patients had arrived from 16 countries, and Malaysia, Indonesia, the Philippines, and China were the most frequent importing countries. Phylogenetic analyses showed that genotype I of dengue virus type 1 (DENV-1) and the cosmopolitan genotype of DENV-2 were the predominant DENV strains circulating in southeast Asia. The 2014 dengue epidemic was the largest ever to occur in Taiwan since World War II, and there were 15,492 laboratory-confirmed indigenous dengue cases. Phylogenetic analysis showed that the explosive dengue epidemic in southern Taiwan was caused by a DENV-1 strain of genotype I imported from Indonesia. There were several possible causes of this outbreak, including delayed notification of the outbreak, limited staff and resources for control measures, abnormal weather conditions, and a serious gas pipeline explosion in the dengue hot spot areas in Kaohsiung City. However, the results of this surveillance indicated that both active and passive surveillance systems should be strengthened so appropriate public health measures can be taken promptly to prevent large-scale dengue outbreaks.

Matched MeSH terms: Dengue Virus/genetics*; Viral Envelope Proteins/genetics; Genome, Viral/genetics
Fulltext Loop-Mediated Isothermal Amplification Assay for Identification of Five Human Plasmodium Species in Malaysia

Lau YL, Lai MY, Fong MY, Jelip J, Mahmud R

Am J Trop Med Hyg, 2016 Feb;94(2):336-339.
PMID: 26598573 DOI: 10.4269/ajtmh.15-0569

The lack of rapid, affordable, and accurate diagnostic tests represents the primary hurdle affecting malaria surveillance in resource- and expertise-limited areas. Loop-mediated isothermal amplification (LAMP) is a sensitive, rapid, and cheap diagnostic method. Five species-specific LAMP assays were developed based on 18S rRNA gene. Sensitivity and specificity of LAMP results were calculated as compared with microscopic examination and nested polymerase chain reaction. LAMP reactions were highly sensitive with the detection limit of one copy for Plasmodium vivax, Plasmodium falciparum, and Plasmodium malariae and 10 copies for Plasmodium knowlesi and Plasmodium ovale. LAMP positively detected all human malaria species in all positive samples (N = 134; sensitivity = 100%) within 35 minutes. All negative samples were not amplified by LAMP (N = 67; specificity = 100%). LAMP successfully detected two samples with very low parasitemia. LAMP may offer a rapid, simple, and reliable test for the diagnosis of malaria in areas where malaria is prevalent.

Matched MeSH terms: Plasmodium/genetics*; RNA, Ribosomal, 18S/genetics; RNA, Protozoan/genetics
Fulltext Diversity and Evolutionary Histories of Human Coronaviruses NL63 and 229E Associated with Acute Upper Respiratory Tract Symptoms in Kuala Lumpur, Malaysia

Al-Khannaq MN, Ng KT, Oong XY, Pang YK, Takebe Y, Chook JB, et al.

Am J Trop Med Hyg, 2016 05 04;94(5):1058-64.
PMID: 26928836 DOI: 10.4269/ajtmh.15-0810

The human alphacoronaviruses HCoV-NL63 and HCoV-229E are commonly associated with upper respiratory tract infections (URTI). Information on their molecular epidemiology and evolutionary dynamics in the tropical region of southeast Asia however is limited. Here, we analyzed the phylogenetic, temporal distribution, population history, and clinical manifestations among patients infected with HCoV-NL63 and HCoV-229E. Nasopharyngeal swabs were collected from 2,060 consenting adults presented with acute URTI symptoms in Kuala Lumpur, Malaysia, between 2012 and 2013. The presence of HCoV-NL63 and HCoV-229E was detected using multiplex polymerase chain reaction (PCR). The spike glycoprotein, nucleocapsid, and 1a genes were sequenced for phylogenetic reconstruction and Bayesian coalescent inference. A total of 68/2,060 (3.3%) subjects were positive for human alphacoronavirus; HCoV-NL63 and HCoV-229E were detected in 45 (2.2%) and 23 (1.1%) patients, respectively. A peak in the number of HCoV-NL63 infections was recorded between June and October 2012. Phylogenetic inference revealed that 62.8% of HCoV-NL63 infections belonged to genotype B, 37.2% was genotype C, while all HCoV-229E sequences were clustered within group 4. Molecular dating analysis indicated that the origin of HCoV-NL63 was dated to 1921, before it diverged into genotype A (1975), genotype B (1996), and genotype C (2003). The root of the HCoV-229E tree was dated to 1955, before it diverged into groups 1-4 between the 1970s and 1990s. The study described the seasonality, molecular diversity, and evolutionary dynamics of human alphacoronavirus infections in a tropical region.

Matched MeSH terms: Viral Proteins/genetics; Coronavirus 229E, Human/genetics*; Coronavirus NL63, Human/genetics*
Fulltext Evaluation of Pichia pastoris-expressed recombinant rhoptry protein 2 of Toxoplasma gondii for its application in diagnosis of toxoplasmosis

Chang PY, Fong MY, Nissapatorn V, Lau YL

Am J Trop Med Hyg, 2011 Sep;85(3):485-9.
PMID: 21896809 DOI: 10.4269/ajtmh.2011.11-0351

Rhoptry protein 2 (ROP2) of Toxoplasma gondii is a rhoptry-secreted protein that plays a critical role in parasitophorous vacuole membrane formation during invasion. In previous studies, ROP2 has been shown to be efficient in triggering humoral and cell-mediated responses. High immunogenicity of ROP2 makes it a potential candidate for diagnosis and vaccination against toxoplasmosis. In this study, the ROP2 gene was cloned into pPICZα A expression vector and extracellularly expressed in the yeast Pichia pastoris, which has numerous advantages over other expression systems for eukaryotic proteins expression. The effectiveness of the secreted recombinant ROP2 as a diagnosis agent was assessed by Western Blot with 200 human serum samples. Recombinant ROP2 reacted with toxoplasmosis-positive human serum samples and yielded an overall sensitivity of 90% and specificity of 95%. However, recombinant ROP2 is a better marker for detection of IgG (91.7%) rather than IgM (80%).

Matched MeSH terms: Membrane Proteins/genetics; Toxoplasma/genetics; Protozoan Proteins/genetics
Overexpression of rice High-affinity Potassium Transporter gene OsHKT1;5 improves salinity and drought tolerance in Arabidopsis

Ullah MA, Abdullah-Zawawi MR, Razalli II, Sukiran NL, Uddin MI, Zainal Z

Mol Biol Rep, 2024 Dec 07;52(1):40.
PMID: 39644345 DOI: 10.1007/s11033-024-10130-6

BACKGROUND: Rice is subjected to various environmental stresses, resulting in significant production losses. Abiotic stresses, particularly drought and salinity, are the leading causes of plant damage worldwide. The High-affinity Potassium Transporter (HKT) gene family plays an important role in enhancing crop stress tolerance by regulating physiological and enzymatic functions.
METHODS AND RESULTS: This study investigates the effect of overexpressing the rice HKT1;5 gene in Arabidopsis thaliana on its tolerance to salinity and drought. The OsHKT1;5 gene was introduced into Arabidopsis under the control of 35 S promoter of CaMV via floral dip transformation method. PCR confirmed the integration of the transgene into the Arabidopsis genome, while qPCR analysis showed its expression. Three transgenic lines of OsHKT1;5 were used for stress treatment and phenotypic studies. The overexpressed lines showed considerably higher germination rates, increased leaf counts, greater fresh and dry weights of the roots and shoots, higher chlorophyll contents, longer root lengths, and reduced Na+ levels together with increased K+ ions levels after salt and drought treatments, in comparison to wild-type plants. Furthermore, overexpressed lines exhibited higher antioxidant levels than wild-type plants under salinity and drought conditions. In addition, transgenic lines showed higher expression levels of the OsHKT1;5 gene in both roots and shoots compared to wild-type plants.
CONCLUSIONS: In conclusion, this study revealed OsHKT1;5 as a promising candidate for enhancing tolerance to salinity and drought stresses in rice, marking a significant step toward developing a new rice variety with improved abiotic stress tolerance.

Matched MeSH terms: Plant Roots/genetics; Germination/genetics; Cation Transport Proteins/genetics
Shallow shotgun sequencing of healthcare waste reveals plastic-eating bacteria with broad-spectrum antibiotic resistance genes

Siew SW, Khairi MHF, Hamid NA, Asras MFF, Ahmad HF

Environ Pollut, 2025 Jan 01;364(Pt 1):125330.
PMID: 39551377 DOI: 10.1016/j.envpol.2024.125330

The burgeoning crises of antimicrobial resistance and plastic pollution are converging in healthcare settings, presenting a complex challenge to global health. This study investigates the microbial populations in healthcare waste to understand the extent of antimicrobial resistance and the potential for plastic degradation by bacteria. Our metagenomic analysis, using both amplicon and shallow shotgun sequencing, provided a comprehensive view of the taxonomic diversity and functional capacity of the microbial consortia. The viable bacteria in healthcare waste samples were analyzed employing full-length 16S rRNA sequencing, revealing a diverse bacterial community dominated by Firmicutes and Proteobacteria phyla. Notably, Proteus mirabilis VFC3/3 and Pseudomonas sp. VFA2/3 were detected, while Stenotrophomonas maltophilia VFV3/2 surfaced as the predominant species, holding implications for the spread of hospital-acquired infections and antimicrobial resistance. Antibiotic susceptibility testing identified multidrug-resistant strains conferring antimicrobial genes, including the broad-spectrum antibiotic carbapenem, underscoring the critical need for improved waste management and infection control measures. Remarkably, we found genes linked to the breakdown of plastic that encoded for enzymes of the esterase, depolymerase, and oxidoreductase classes. This suggests that specific bacteria found in medical waste may be able to reduce the amount of plastic pollution that comes from biological and medical waste. The information is helpful in formulating strategies to counter the combined problems of environmental pollution and antibiotic resistance. This study emphasises the importance of monitoring microbial communities in hospital waste in order to influence waste management procedures and public health policy. The findings highlight the need for a multidisciplinary approach to mitigate the risks associated with antimicrobial resistance and plastic waste, especially in hospital settings where they intersect most acutely.

Matched MeSH terms: Drug Resistance, Microbial/genetics; RNA, Ribosomal, 16S/genetics; Drug Resistance, Bacterial/genetics

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