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Fulltext Aptamer-Antibody Complementation On Multiwalled Carbon Nanotube-Gold Transduced Dielectrode Surfaces To Detect Pandemic Swine Influenza Virus

Wang F, Gopinath SC, Lakshmipriya T

Int J Nanomedicine, 2019;14:8469-8481.
PMID: 31695375 DOI: 10.2147/IJN.S219976

BACKGROUND: A pandemic influenza viral strain, influenza A/California/07/2009 (pdmH1N1), has been considered to be a potential issue that needs to be controlled to avoid the seasonal emergence of mutated strains.
MATERIALS AND METHODS: In this study, aptamer-antibody complementation was implemented on a multiwalled carbon nanotube-gold conjugated sensing surface with a dielectrode to detect pandemic pdmH1N1. Preliminary biomolecular and dielectrode surface analyses were performed by molecular and microscopic methods. A stable anti-pdmH1N1 aptamer sequence interacted with hemagglutinin (HA) and was compared with the antibody interaction. Both aptamer and antibody attachments on the surface as the basic molecule attained the saturation at nanomolar levels.
RESULTS: Aptamers were found to have higher affinity and electric response than antibodies against HA of pdmH1N1. Linear regression with aptamer-HA interaction displays sensitivity in the range of 10 fM, whereas antibody-HA interaction shows a 100-fold lower level (1 pM). When sandwich-based detection of aptamer-HA-antibody and antibody-HA-aptamer was performed, a higher response of current was observed in both cases. Moreover, the detection strategy with aptamer clearly discriminated the closely related HA of influenza B/Tokyo/53/99 and influenza A/Panama/2007/1999 (H3N2).
CONCLUSION: The high performance of the abovementioned detection methods was supported by the apparent specificity and reproducibility by the demonstrated sensing system.

Matched MeSH terms: Hemagglutinin Glycoproteins, Influenza Virus/metabolism
Effects of the ABCB1 C3435T single nucleotide polymorphism on major adverse cardiovascular events in acute coronary syndrome or coronary artery disease patients undergoing percutaneous coronary intervention and treated with clopidogrel: A systematic review and meta-analysis

Biswas M, Rahaman S, Biswas TK, Ibrahim B

Expert Opin Drug Saf, 2020 Dec;19(12):1605-1616.
PMID: 33040624 DOI: 10.1080/14740338.2020.1836152

INTRODUCTION: The effects of the ABCB1 C3435T genetic polymorphism on clopidogrel responses are conflicting and inconclusive especially in patients undergoing percutaneous coronary intervention (PCI). This study examined the pooled risk of major adverse cardiovascular events (MACE) and bleeding events associated with the ABCB1 C3435T polymorphism in acute coronary syndrome or coronary artery disease patients undergoing PCI and treated with clopidogrel.
AREAS COVERED: Literature was searched in different resources for eligible studies. The pooled risk ratio was measured using RevMan software, with p<0.05 (two-sided) set as statistically significant.
EXPERT OPINION: The ABCB1 C3435T homozygous mutant (TT) was associated with significantly increased risk of MACE compared to either wild type genotype (CC) or the combination of wild type and heterozygous genotypes (TT vs. CC: RR 1.33; 95% CI 1.06-1.68; p=0.02; TT vs. CC+CT: RR 1.32; 95% CI 1.10-1.60; p=0.004). Safety outcomes, i.e. bleeding events were not significantly different between the genetic models investigated (TT vs. CC: RR 1.93; 95% CI 0.86-4.35; p=0.11; TT vs. CC+CT: RR 1.36; 95% CI 0.89-2.09; p=0.16; CT+TT vs. CC: RR 1.20; 95% CI 0.59-2.44; p=0.61). It is suggested that ABCB1 C3435T genotype should be tested for ACS/CAD patients undergoing PCI to ensure optimum therapy of clopidogrel.

Matched MeSH terms: P-Glycoproteins/genetics
Fulltext Pharmacogenomics biomarkers for personalized methadone maintenance treatment: The mechanism and its potential use

Ramli FF

Bosn J Basic Med Sci, 2021 Apr 01;21(2):145-154.
PMID: 32841585 DOI: 10.17305/bjbms.2020.4897

Methadone has a wide pharmacokinetic interindividual variability, resulting in unpredicted treatment response. Pharmacogenomic biomarkers seem promising for personalized methadone maintenance treatment. The evidence supports the use of ABCB1 single-nucleotide polymorphism (SNP) 1236C>T with genotypes C/T or C/C (Jewish) and haplotypes AGCTT carrier, AGCGC heterozygote, or non-carrier (Caucasian), which have a predicted lower methadone dose requirement. In contrast, ABCB1 SNP 1236C>T with genotype T/T (Jewish); haplotypes AGCGC homozygote, AGCTT non-carrier (Caucasian), and ABCB1 3435C>T variant carrier; and haplotypes CGT, TTC, and TGT (Han Chinese) have a predicted higher methadone dose. For methadone plasma levels, ABCB1 diplotype non-CGC/TTT (Malay) predicted lower, and diplotype CGC/TTT (Malay), 3435C>T allelic carrier, haplotypes (CGT, TTC, TGT) (Han Chinese) predicted higher methadone levels. In terms of metabolism biomarkers, a lower methadone requirement was related to carriers of CYP2B6 genotypes *4(G/G) and *9(T/T) among Jewish patients, CYP2B6*9 genotype (T/T) and haplotypes (TA/TG); and CYP2C19 (*2/*2,*2/*3, and *3/*3; Han Chinese). Higher methadone dose was observed in CYP2C19*1 allelic carriers (Han Chinese) and CYP2D6 ultrarapid metabolizer (Caucasian). Lower methadone levels were reported in CYP2B6 SNPs, haplotypes TTT, and AGATAA (Han Chinese), CYP2C19 genotype *1/*1 (Han Chinese), allelic carrier *1xN (Caucasian), and CYP3A4 genotype *1/*1 (Caucasian). Carriers of CYP2B6 genotype *6/*6 (Caucasian), CYP2B6 haplotypes ATGCAG and ATGCTG (Han Chinese), and CYP3A4 genotype *1/*1B (Caucasian) had predicted higher methadone plasma levels. Specific pharmacokinetics biomarkers have potential uses for personalized methadone treatment in specific populations.

Matched MeSH terms: P-Glycoproteins/genetics
Aberrant expression of acute-phase reactant proteins in sera and breast lesions of patients with malignant and benign breast tumors

Doustjalali SR, Yusof R, Yip CH, Looi LM, Pillay B, Hashim OH

Electrophoresis, 2004 Jul;25(14):2392-401.
PMID: 15274022

We have analyzed unfractionated sera of newly diagnosed patients (n=10) with breast carcinoma (BC), prior to treatment, and patients (n=5) with fibrocystic disease of the breast (FDB) by two-dimensional gel electrophoresis (2-DE) and silver staining. The patients' 2-DE serum protein profiles obtained were then subjected to image analysis and compared to similar data generated from sera of normal healthy female controls (n=10) of the same range of age. The relative expression of alpha1-antichymotrypsin (ACT), clusterin, and complement factor B was significantly higher in all BC patients as compared to normal controls. However, the expression of alpha1-antitrypsin (AAT) in BC patients was apparently lower than that of the controls. Similar differential expression of ACT was detected in the FDB patients. The aberrant expression of the serum acute-phase proteins of patients with BC and FDB was confirmed by competitive enzyme-linked immunosorbent assay (ELISA). Similar altered proteins expression was also observed from immunohistochemical studies of malignant (n=5) and benign (n=5) breast lesions of the respective patients performed using antisera to the aberrantly expressed proteins. However, the malignant breast lesions were instead positively stained for AAT. The differential expression of the serum proteins was apparently abrogated when a six-month follow-up study was performed on nine of the BC patients subsequent to treatment.

Matched MeSH terms: Glycoproteins/metabolism
Fulltext Serum Wisteria floribunda agglutinin-positive Mac-2 binding protein in non-alcoholic fatty liver disease

Lai LL, Chan WK, Sthaneshwar P, Nik Mustapha NR, Goh KL, Mahadeva S

PLoS One, 2017;12(4):e0174982.
PMID: 28369100 DOI: 10.1371/journal.pone.0174982

Wisteria floribunda agglutinin-positive Mac-2 binding protein (WFA+-M2BP) has been suggested to be useful for the assessment of disease severity in non-alcoholic fatty liver disease (NAFLD). Consecutive adult NAFLD patients who had a liver biopsy were included. Serum WFA+-M2BP level was measured using a lectin-antibody sandwich immunoassay using a chemiluminescence enzyme immunoassay machine (HISCL-5000, Sysmex, Kobe, Japan). The measured levels were indexed using the following equation: Cut-off index (COI) = ([WFA+-M2BP]sample-[WFA+-M2BP]NC) / ([WFA+-M2BP]PC-[WFA+-M2BP]NC), where PC = positive control and NC = negative control. Histopathological examination of liver biopsy specimen was reported according to Non-Alcoholic Steatohepatitis (NASH) Clinical Research Network Scoring System. Data for 220 cases were analyzed. The AUROC of the COI for the diagnosis of NASH was 0.65. The AUROC of the COI for the diagnosis of steatosis grade ≥2 and 3 was 0.64 and 0.53, respectively. The AUROC of the COI for the diagnosis of lobular inflammation grade ≥1, ≥2 and 3 was 0.57, 0.68 and 0.59, respectively. The AUROC of the COI for the diagnosis of hepatocyte ballooning grade ≥1 and 2 was 0.64 and 0.65, respectively. The AUROC of the COI for the diagnosis of fibrosis stage ≥1, ≥2, ≥3 and 4 was 0.61, 0.71, 0.74 and 0.84, respectively. Out of the 220 cases, 152 cases were the same 76 patients who had a repeat liver biopsy after 48 weeks of intervention. The AUROC of the change in the COI to detect improvement in steatosis, lobular inflammation, hepatocyte ballooning and fibrosis was 0.57, 0.54, 0.59 and 0.52, respectively. In conclusion, serum WFA+-M2BP was most useful for the diagnosis of significant fibrosis, advanced fibrosis and cirrhosis in NAFLD patients. However, it was less useful for differentiating NASH from non-NASH, and for diagnosis and follow-up of the individual histopathological components of NASH.

Matched MeSH terms: Membrane Glycoproteins/blood*
Antidiabetic effects of Brucea javanica seeds in type 2 diabetic rats

Ablat A, Halabi MF, Mohamad J, Hasnan MH, Hazni H, Teh SH, et al.

BMC Complement Altern Med, 2017 Feb 06;17(1):94.
PMID: 28166749 DOI: 10.1186/s12906-017-1610-x

Brucea javanica (B. javanica) seeds, also known as "Melada pahit" in Indo-Malay region are traditionally used to treat diabetes. The objective of this study was to determine antidiabetic, antioxidant and anti-inflammatory effects of B. javanica seeds on nicotinamide (NA)-streptozotocin (STZ) induced type 2 diabetic (T2D) rats and to analyze its chemical composition that correlate with their pharmacological activities.

Matched MeSH terms: Glycoproteins/drug effects*
Fulltext Aberrant monocyte responses predict and characterize dengue virus infection in individuals with severe disease

Yong YK, Tan HY, Jen SH, Shankar EM, Natkunam SK, Sathar J, et al.

J Transl Med, 2017 05 31;15(1):121.
PMID: 28569153 DOI: 10.1186/s12967-017-1226-4

BACKGROUND: Currently, several assays can diagnose acute dengue infection. However, none of these assays can predict the severity of the disease. Biomarkers that predicts the likelihood that a dengue patient will develop a severe form of the disease could permit more efficient patient triage and allows better supportive care for the individual in need, especially during dengue outbreaks.
METHODS: We measured 20 plasma markers i.e. IFN-γ, IL-10, granzyme-B, CX3CL1, IP-10, RANTES, CXCL8, CXCL6, VCAM, ICAM, VEGF, HGF, sCD25, IL-18, LBP, sCD14, sCD163, MIF, MCP-1 and MIP-1β in 141 dengue patients in over 230 specimens and correlate the levels of these plasma markers with the development of dengue without warning signs (DWS-), dengue with warning signs (DWS+) and severe dengue (SD).
RESULTS: Our results show that the elevation of plasma levels of IL-18 at both febrile and defervescence phase was significantly associated with DWS+ and SD; whilst increase of sCD14 and LBP at febrile phase were associated with severity of dengue disease. By using receiver operating characteristic (ROC) analysis, the IL-18, LBP and sCD14 were significantly predicted the development of more severe form of dengue disease (DWS+/SD) (AUC = 0.768, P

Matched MeSH terms: Membrane Glycoproteins/blood
Fulltext Co-administration of avian influenza virus H5 plasmid DNA with chicken IL-15 and IL-18 enhanced chickens immune responses

Lim KL, Jazayeri SD, Yeap SK, Alitheen NB, Bejo MH, Ideris A, et al.

BMC Vet Res, 2012;8:132.
PMID: 22866758 DOI: 10.1186/1746-6148-8-132

DNA vaccines offer several advantages over conventional vaccines in the development of effective vaccines against avian influenza virus (AIV). However, one of the limitations of the DNA vaccine in poultry is that it induces poor immune responses. In this study, chicken interleukin (IL) -15 and IL-18 were used as genetic adjuvants to improve the immune responses induced from the H5 DNA vaccination in chickens. The immunogenicity of the recombinant plasmid DNA was analyzed based on the antibody production, T cell responses and cytokine production, following inoculation in 1-day-old (Trial 1) and 14-day-old (Trial 2) specific-pathogen-free chickens. Hence, the purpose of the present study was to explore the role of chicken IL-15 and IL-18 as adjuvants following the vaccination of chickens with the H5 DNA vaccine.

Matched MeSH terms: Hemagglutinin Glycoproteins, Influenza Virus/immunology*
Identification of a functional variant in SPLUNC1 associated with nasopharyngeal carcinoma susceptibility among Malaysian Chinese

Yew PY, Mushiroda T, Kiyotani K, Govindasamy GK, Yap LF, Teo SH, et al.

Mol Carcinog, 2012 Oct;51 Suppl 1:E74-82.
PMID: 22213098 DOI: 10.1002/mc.21857

Nasopharyngeal carcinoma (NPC) is a multifactorial and polygenic disease with high incidence in Asian countries. Epstein-Barr virus infection, environmental and genetic factors are believed to be involved in the tumorigenesis of NPC. The association of single nucleotide polymorphisms (SNPs) in LPLUNC1 and SPLUNC1 genes with NPC was investigated by performing a two-stage case control association study in a Malaysian Chinese population. The initial screening consisted of 81 NPC patients and 147 healthy controls while the replication study consisted of 366 NPC patients and 340 healthy controls. The combined analysis showed that a SNP (rs2752903) of SPLUNC1 was significantly associated with the risk of NPC (combined P = 0.00032, odds ratio = 1.62, 95% confidence interval = 1.25-2.11). In the subsequent dense fine mapping of SPLUNC1 locus, 36 SNPs in strong linkage disequilibrium with rs2752903 (r(2) ≥ 0.85) were associated with NPC susceptibility. Screening of these variants by electrophoretic mobility shift and luciferase reporter assays showed that rs1407019 located in intron 3 (r(2) = 0.994 with rs2752903) caused allelic difference in the binding of specificity protein 1 (Sp1) transcription factor and affected luciferase activity. This SNP may consequently alter the expression of SPLUNC1 in the epithelial cells. In summary, our study suggested that rs1407019 in intronic enhancer of SPLUNC1 is associated with NPC susceptibility in which its A allele confers an increased risk of NPC in the Malaysian Chinese population.

Matched MeSH terms: Glycoproteins/genetics*
Differential expression of canonical and non-canonical Wnt ligands in ameloblastoma

Siar CH, Nagatsuka H, Han PP, Buery RR, Tsujigiwa H, Nakano K, et al.

J Oral Pathol Med, 2012 Apr;41(4):332-9.
PMID: 22077561 DOI: 10.1111/j.1600-0714.2011.01104.x

Canonical and non-canonical Wnt signaling pathways modulate diverse cellular processes during embryogenesis and post-natally. Their deregulations have been implicated in cancer development and progression. Wnt signaling is essential for odontogenesis. The ameloblastoma is an odontogenic epithelial neoplasm of enamel organ origin. Altered expressions of Wnts-1, -2, -5a, and -10a are detected in this tumor. The activity of other Wnt members remains unclarified.

Matched MeSH terms: Glycoproteins/genetics
Neonatal dexamethasone exposure down-regulates GnRH expression through the GnIH pathway in female mice

Soga T, Dalpatadu SL, Wong DW, Parhar IS

Neuroscience, 2012 Aug 30;218:56-64.
PMID: 22626647 DOI: 10.1016/j.neuroscience.2012.05.023

Synthetic glucocorticoid (dexamethasone; DEX) treatment during the neonatal stage is known to affect reproductive activity. However, it is still unknown whether neonatal stress activates gonadotropin-inhibitory hormone (GnIH) synthesizing cells in the dorsomedial hypothalamus (DMH), which could have pronounced suppressive action on gonadotropin-releasing hormone (GnRH) neurons, leading to delayed pubertal onset. This study was designed to determine the effect of neonatal DEX (1.0mg/kg) exposure on reproductive maturation. Therefore, GnRH, GnIH and GnIH receptors, G-protein coupled receptors (GPR) 147 and GPR74 mRNA levels were measured using quantitative real-time PCR in female mice at postnatal (P) days 21, 30 and in estrus stage mice, aged between P45-50. DEX-treated females of P45-50 had delayed vaginal opening, and irregular estrus cycles and lower GnRH expression in the preoptic area (POA) when compared with age-matched controls. The expression levels of GPR147 and GPR74 mRNA in the POA increased significantly in DEX-treated female mice of P21 and P45-50 compared to controls. In addition, GPR147 and GPR74 mRNA expression was observed in laser captured single GnRH neurons in the POA. Although there was no difference in GnIH mRNA expression in the DMH, immunostained GnIH cell numbers in the DMH increased in DEX-treated females of P45-50 compared to controls. Taken together, the results show that the delayed pubertal onset could be due to the inhibition of GnRH gene expression after neonatal DEX treatment, which may be accounted for in part by the inhibitory signals from the up-regulated GnIH-GnIH receptor pathway to the POA.

Matched MeSH terms: Glycoproteins/metabolism*
Fulltext Identification of MYOC gene mutation and polymorphism in a large Malay family with juvenile-onset open angle glaucoma

Mimivati Z, Nurliza K, Marini M, Liza-Sharmini A

Mol Vis, 2014;20:714-23.
PMID: 24883016

PURPOSE:
To screen for mutations in the coding region of the myocilin (MYOC) gene in a large Malay family with juvenile-onset open angle glaucoma (JOAG).

METHODS:
A total of 122 family members were thoroughly examined and screened for JOAG. Venipuncture was conducted. Genomic DNA was extracted from peripheral blood leukocytes. The presence of a mutation and a polymorphism was ascertained with PCR amplification followed by the direct sequencing technique.

RESULTS:
Thirty-two of the 122 screened family members were identified to have JOAG (11 new cases and 21 known cases). An autosomal dominant inheritance pattern with incomplete penetrance was observed. A C→A substitution at position 1440 in exon 3 that changes asparagine (AAC) to lysine (AAA) was identified in affected family members except two probands (III:5 and IV:6). Six probands were identified as having the Asn480Lys mutation but have not developed the disease yet. An intronic polymorphism IVS2 730 +35 G>A was also identified. There was a significant association between Asn480Lys (p<0.001) and IVS2 730+35G>A (p<0.001) in the affected and unaffected probands in this family.

CONCLUSIONS:
The Asn480Lys mutation and the IVS2 730+35 G>A polymorphism increased susceptibility to JOAG in this large Malay pedigree. Identifying the MYOC mutations and polymorphisms is important for providing presymptomatic molecular diagnosis.

Matched MeSH terms: Glycoproteins/genetics*
Cold adaptation improves the growth of seasonal influenza B vaccine viruses

Kim H, Schoofs P, Anderson DA, Tannock GA, Rockman SP

Vaccine, 2014 May 1;32(21):2474-9.
PMID: 24631096 DOI: 10.1016/j.vaccine.2014.02.079

Gene reassortment has proved useful in improving yields of influenza A antigens of egg-based inactivated vaccines, but similar approaches have been difficult with influenza B antigens. Current regulations for influenza vaccine seed viruses limit the number of egg passages and as a result resultant yields from influenza B vaccine seed viruses are frequently inconsistent. Therefore, reliable approaches to enhance yields of influenza B vaccine seed viruses are required for efficient vaccine manufacture. In the present study three stable cold-adapted (ca) mutants, caF, caM and caB derived from seasonal epidemic strains, B/Florida/4/2006, B/Malaysia/2506/2004 and B/Brisbane/60/2008 were prepared, which produced high hemagglutinin antigen yields and also increased viral yields of reassortants possessing the desired 6:2 gene constellation. The results demonstrate that consistent improvements in yields of influenza B viruses can be obtained by cold adaptation following extended passage. Taken together, the three ca viruses were shown to have potential as donor viruses for the preparation of high-yielding influenza B vaccine viruses by reassortment.

Matched MeSH terms: Hemagglutinin Glycoproteins, Influenza Virus/isolation & purification
Fulltext Inhibitory effects of phylligenin and quebrachitol isolated from Mitrephora vulpina on platelet activating factor receptor binding and platelet aggregation

Moharam BA, Jantan I, Jalil J, Shaari K

Molecules, 2010 Nov 03;15(11):7840-8.
PMID: 21060292 DOI: 10.3390/molecules15117840

Phylligenine, together with quebrachitol, stigmasterol and two aporphine alkaloids--oxoputerine and liriodenine--were isolated from the twigs of Mitrephora vulpina C.E.C. Fisch. They were evaluated for their ability to inhibit platelet activating factor (PAF) receptor binding to rabbit platelets using 3H-PAF as a ligand and their antiplatelet aggregation effect in human whole blood induced by arachidonic acid (AA), collagen and adenosine diphosphate (ADP). Of all the compounds tested, phylligenin and quebrachitol exhibited potent and concentration-dependent inhibitory effects on PAF receptor binding, with IC(50) values of 13.1 and 42.2 µM, respectively. The IC(50) value of phylligenin was comparable to that of cedrol (10.2 µM), a potent PAF antagonist. Phylligenin also showed strong dose-dependent inhibitory activity on platelet aggregation induced by AA and ADP.

Matched MeSH terms: Platelet Membrane Glycoproteins/metabolism*
Fulltext Molecular analysis of 2009 pandemic influenza A(H1N1) in Malaysia associated with mild and severe infections

Balraj P, Sidek H, Suppiah J, Khoo AS, Saat Z

Malays J Pathol, 2011 Jun;33(1):7-12.
PMID: 21874745 MyJurnal

The 2009 pandemic influenza A(H1N1) was first detected in Malaysia in May 2009. It quickly spread in the general population and contributed to a number of influenza-like illness. The objective of the study is to characterize genetic changes in early Malaysian isolates of mild and severe illness of the novel influenza, and to compare sequences of viruses circulating in Malaysia to those in other countries between May to September 2009. Viral isolates of 56 mild cases and 10 severe (intensive care unit or fatal) cases were sequenced for haemagglutinin (HA) and neuraminidase (NA). Genome sequencing of the viral RNA was conducted on 5 isolates (3 were from fatal cases). Highly conserved sequences with few sporadic variations were identified in HA and NA. E374K and D222N were identified in 2 viral isolates from patients with severe illness. Phylogenetic analysis showed close genetic relatedness to the vaccine strain A/California/07/09 and other isolates circulating worldwide during the same period. Sporadic variations were identified in the viral isolates, however a larger sample size is required to make associations with disease severity.

Matched MeSH terms: Hemagglutinin Glycoproteins, Influenza Virus/genetics*
Fulltext Antiplatelet aggregation and platelet activating factor (PAF) receptor antagonistic activities of the essential oils of five Goniothalamus species

Moharam BA, Jantan I, Ahmad Fb, Jalil J

Molecules, 2010 Aug;15(8):5124-38.
PMID: 20714290 DOI: 10.3390/molecules15085124

Nine essential oils, hydrodistilled from different parts of five Goniothalamus species (G. velutinus Airy-Shaw, G. woodii Merr., G. clemensii Ban, G. tapis Miq. and G. tapisoides Mat Salleh) were evaluated for their ability to inhibit platelet aggregation in human whole blood using an electrical impedance method and their inhibitory effects on platelet activating factor (PAF) receptor binding with rabbit platelets using 3H-PAF as a ligand. The chemical composition of the oils was analyzed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). The bark oil of G. velutinus was the most effective sample as it inhibited both arachidonic acid (AA) and ADP-induced platelet aggregation with IC(50) values of 93.6 and 87.7 microg/mL, respectively. Among the studied oils, the bark oils of G. clemensii, G. woodii, G. velutinus and the root oil of G. tapis showed significant inhibitory effects on PAF receptor binding, with IC(50 )values ranging from 3.5 to 10.5 microg/mL. The strong PAF antagonistic activity of the active oils is related to their high contents of sesquiterpenes and sesquiterpenoids, and the individual components in the oils could possibly produce a synergistic effect in the overall antiplatelet activity of the oils.

Matched MeSH terms: Platelet Membrane Glycoproteins/antagonists & inhibitors*
Fulltext Identification of the progenitors of Indonesian and Vietnamese avian influenza A (H5N1) viruses from southern China

Wang J, Vijaykrishna D, Duan L, Bahl J, Zhang JX, Webster RG, et al.

J Virol, 2008 Apr;82(7):3405-14.
PMID: 18216109 DOI: 10.1128/JVI.02468-07

The transmission of highly pathogenic avian influenza H5N1 virus to Southeast Asian countries triggered the first major outbreak and transmission wave in late 2003, accelerating the pandemic threat to the world. Due to the lack of influenza surveillance prior to these outbreaks, the genetic diversity and the transmission pathways of H5N1 viruses from this period remain undefined. To determine the possible source of the wave 1 H5N1 viruses, we recently conducted further sequencing and analysis of samples collected in live-poultry markets from Guangdong, Hunan, and Yunnan in southern China from 2001 to 2004. Phylogenetic analysis of the hemagglutinin and neuraminidase genes of 73 H5N1 isolates from this period revealed a greater genetic diversity in southern China than previously reported. Moreover, results show that eight viruses isolated from Yunnan in 2002 and 2003 were most closely related to the clade 1 virus sublineage from Vietnam, Thailand, and Malaysia, while two viruses from Hunan in 2002 and 2003 were most closely related to viruses from Indonesia (clade 2.1). Further phylogenetic analyses of the six internal genes showed that all 10 of those viruses maintained similar phylogenetic relationships as the surface genes. The 10 progenitor viruses were genotype Z and shared high similarity (>/=99%) with their corresponding descendant viruses in most gene segments. These results suggest a direct transmission link for H5N1 viruses between Yunnan and Vietnam and also between Hunan and Indonesia during 2002 and 2003. Poultry trade may be responsible for virus introduction to Vietnam, while the transmission route from Hunan to Indonesia remains unclear.

Matched MeSH terms: Hemagglutinin Glycoproteins, Influenza Virus/genetics
Molecular epidemiology of rabies in Vietnam

Yamagata J, Ahmed K, Khawplod P, Mannen K, Xuyen DK, Loi HH, et al.

Microbiol. Immunol., 2007;51(9):833-40.
PMID: 17895600

The present study was done to determine the molecular epidemiology of rabies virus (RV) in Vietnam. The nucleoprotein (N) and glycoprotein (G) genes of RVs were amplified from the brains of ten rabid dogs of Ho Chi Minh City, Vietnam. The nucleotide sequences of these genes were compared with those of other Asian strains to find the possible relationship among them. Phylogenetic analysis revealed that the Asian N gene segregated into three main branches, namely South-East Asia 1 (SEA 1), South-East Asia 2 (SEA 2) and Indian subcontinent (ISC) genotypes. The SEA 1 genotype comprised RVs from Malaysia, Vietnam and Thailand. The SEA 2 genotype contained strains from the Philippines, and the ISC genotype comprised strains from Sri Lanka and India. Phylogenetically G genes of RVs from Vietnam and Thailand were clustered together. Our study suggests that Vietnamese and Thai RVs are closely related and might have originated from a common ancestor.

Matched MeSH terms: Glycoproteins/genetics
Platelet-activating factor (PAF) receptor binding antagonist activity of the methanol extracts and isolated flavonoids from Chromolaena odorata (L.) King and Robinson

Ling SK, Pisar MM, Man S

Biol Pharm Bull, 2007 Jun;30(6):1150-2.
PMID: 17541171

The leaf, stem and root extracts of Chromolaena odorata were evaluated for their effect on platelet-activating factor (PAF) receptor binding on rabbit platelets using 3H-PAF as a ligand. The leaf extract demonstrated high PAF receptor binding inhibitory activity of 79.2+/-2.1% at 18.2 microg/ml. A total of eleven flavonoids were subsequently isolated from the active leaf extract and evaluated for their effects on PAF receptor binding. Eight of the flavonoids exhibited >50% inhibition on the binding activity at 18.2 microg/ml. These flavonoids were identified as eriodictyol 7,4'-dimethyl ether, quercetin 7,4'-methyl ether, naringenin 4'-methyl ether, kaempferol 4'-methyl ether, kaempferol 3-O-rutinoside, taxifolin 4'-methyl ether, taxifolin 7-methyl ether and quercetin 4'-methyl ether. Their IC50 values ranged from 19.5 to 62.1 microM.

Matched MeSH terms: Platelet Membrane Glycoproteins/antagonists & inhibitors*
Fulltext Progress and challenges toward the development of vaccines against avian infectious bronchitis

Bande F, Arshad SS, Bejo MH, Moeini H, Omar AR

J Immunol Res, 2015;2015:424860.
PMID: 25954763 DOI: 10.1155/2015/424860

Avian infectious bronchitis (IB) is a widely distributed poultry disease that has huge economic impact on poultry industry. The continuous emergence of new IBV genotypes and lack of cross protection among different IBV genotypes have been an important challenge. Although live attenuated IB vaccines remarkably induce potent immune response, the potential risk of reversion to virulence, neutralization by the maternal antibodies, and recombination and mutation events are important concern on their usage. On the other hand, inactivated vaccines induce a weaker immune response and may require multiple dosing and/or the use of adjuvants that probably have potential safety risks and increased economic burdens. Consequently, alternative IB vaccines are widely sought. Recent advances in recombinant DNA technology have resulted in experimental IB vaccines that show promise in antibody and T-cells responses, comparable to live attenuated vaccines. Recombinant DNA vaccines have also been enhanced to target multiple serotypes and their efficacy has been improved using delivery vectors, nanoadjuvants, and in ovo vaccination approaches. Although most recombinant IB DNA vaccines are yet to be licensed, it is expected that these types of vaccines may hold sway as future vaccines for inducing a cross protection against multiple IBV serotypes.

Matched MeSH terms: Glycoproteins/immunology

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