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Fulltext Implications of a highly divergent dengue virus strain for cross-neutralization, protection, and vaccine immunity

Chen RE, Smith BK, Errico JM, Gordon DN, Winkler ES, VanBlargan LA, et al.

Cell Host Microbe, 2021 Nov 10;29(11):1634-1648.e5.
PMID: 34610295 DOI: 10.1016/j.chom.2021.09.006

Although divergent dengue viruses (DENVs) have been isolated in insects, nonhuman primates, and humans, their relationships to the four canonical serotypes (DENV 1-4) are poorly understood. One virus isolated from a dengue patient, DKE-121, falls between genotype and serotype levels of sequence divergence to DENV-4. To examine its antigenic relationship to DENV-4, we assessed serum neutralizing and protective activity. Whereas DENV-4-immune mouse sera neutralize DKE-121 infection, DKE-121-immune sera inhibit DENV-4 less efficiently. Passive transfer of DENV-4 or DKE-121-immune sera protects mice against homologous, but not heterologous, DENV-4 or DKE-121 challenge. Antigenic cartography suggests that DENV-4 and DKE-121 are related but antigenically distinct. However, DENV-4 vaccination confers protection against DKE-121 in nonhuman primates, and serum from humans immunized with a tetravalent vaccine neutralize DENV-4 and DKE-121 infection equivalently. As divergent DENV strains, such as DKE-121, may meet criteria for serotype distinction, monitoring their capacity to impact dengue disease and vaccine efficacy appears warranted.

Matched MeSH terms: Antigens, Viral/immunology
Fulltext Transmission routes for nipah virus from Malaysia and Bangladesh

Clayton BA, Middleton D, Bergfeld J, Haining J, Arkinstall R, Wang L, et al.

Emerg Infect Dis, 2012 Dec;18(12):1983-93.
PMID: 23171621 DOI: 10.3201/eid1812.120875

Human infections with Nipah virus in Malaysia and Bangladesh are associated with markedly different patterns of transmission and pathogenicity. To compare the 2 strains, we conducted an in vivo study in which 2 groups of ferrets were oronasally exposed to either the Malaysia or Bangladesh strain of Nipah virus. Viral shedding and tissue tropism were compared between the 2 groups. Over the course of infection, significantly higher levels of viral RNA were recovered from oral secretions of ferrets infected with the Bangladesh strain. Higher levels of oral shedding of the Bangladesh strain of Nipah virus might be a key factor in onward transmission in outbreaks among humans.

Matched MeSH terms: Antigens, Viral/metabolism
Fulltext Intermittent respiratory obstruction secondary to a solitary fibrous tumour

Shashinder S, Kuljit S, Rahmat O, Usha DA, Gopala GK

Med J Malaysia, 2006 Oct;61(4):501-2.
PMID: 17243534 MyJurnal

There have been fourteen cases of solitary fibrous tumour reported as originating from the paranasal sinuses. Here we report a case of solitary fibrous tumour that involved the right nasal cavity with extension into the oropharynx causing stertor and intermittent respiratory obtruction. Histopathology examination revealed the tumuor cells expressed CD34 turnout marker.

Matched MeSH terms: Antigens, CD34
Hev b 5 and Hev b 13 as allergen markers to estimate the allergenic potency of latex gloves

Yeang HY, Arif SA, Raulf-Heimsoth M, Loke YH, Sander I, Sulong SH, et al.

J Allergy Clin Immunol, 2004 Sep;114(3):593-8.
PMID: 15356563 DOI: 10.1016/j.jaci.2004.05.039

BACKGROUND:
Sensitization to natural rubber latex has been linked to proteins from medical latex gloves. Various assays to estimate the amount of residual allergenic proteins extractable from latex gloves to assess their potential exposure hazard have inherent weaknesses.

OBJECTIVE:
This investigation was aimed at developing 2-site immunoenzymetric assays and identifying appropriate protein markers to assess the allergenic potential of latex gloves.

METHODS:
The presence of 6 latex allergens--Hev b 1, 2, 3, 5, 6, and 13--was measured in a cross-section of commercial latex medical gloves by using monoclonal and polyclonal antibody-based 2-site immunoenzymetric assays. The overall allergenic potential of these gloves was assessed by IgE-inhibition assay. Stepwise multiple regression analyses were performed to identify marker allergens that best explained the variation in latex glove allergenicity.

RESULTS:
All 6 latex allergens were detected in at least some of the glove samples. Hev b 5 and Hev b 13 were identified as the marker allergens that combined best to explain the variation in the glove allergenicity. The significant multiple correlation (R=0.855) between these 2 markers and glove allergenic potency forms the basis of an assay to gauge latex glove allergenicity.

CONCLUSION:
The overall allergenic potential of latex gloves can be estimated by using Hev b 5 and Hev b 13 as indicator allergens. The correlation between glove allergenicity and the level of these allergens was maintained for low-protein gloves (<200 microg/g). This estimation of glove allergenicity was superior to that obtained by using total protein readings.

Matched MeSH terms: Antigens, Plant
Expression and purification of the matrix protein of Nipah virus in baculovirus insect cell system

Masoomi Dezfooli S, Tan WS, Tey BT, Ooi CW, Hussain SA

Biotechnol Prog, 2016 Jan-Feb;32(1):171-7.
PMID: 26519022 DOI: 10.1002/btpr.2192

Nipah virus (NiV) causes fatal respiratory illness and encephalitis in humans and animals. The matrix (M) protein of NiV plays an important role in the viral assembly and budding process. Thus, an access to the NiV M protein is vital to the design of viral antigens as diagnostic reagents. In this study, recombinant DNA technology was successfully adopted in the cloning and expression of NiV M protein. A recombinant expression cassette (baculovirus expression vector) was used to encode an N-terminally His-tagged NiV M protein in insect cells. A time-course study demonstrated that the highest yield of recombinant M protein (400-500 μg) was expressed from 107 infected cells 3 days after infection. A single-step purification method based on metal ion affinity chromatography was established to purify the NiV M protein, which successfully yielded a purity level of 95.67% and a purification factor of 3.39. The Western blotting and enzyme-linked immunosorbent assay (ELISA) showed that the purified recombinant M protein (48 kDa) was antigenic and reacted strongly with the serum of a NiV infected pig.

Matched MeSH terms: Antigens, Viral
Enterovirus-Specific Anti-peptide Antibodies

Poh CL, Kirk K, Chua HN, Grollo L

Methods Mol Biol, 2015;1348:341-50.
PMID: 26424285 DOI: 10.1007/978-1-4939-2999-3_29

Enterovirus 71 (EV-71) is the main causative agent of hand, foot, and mouth disease (HFMD) which is generally regarded as a mild childhood disease. In recent years, EV71 has emerged as a significant pathogen capable of causing high mortalities and severe neurological complications in large outbreaks in Asia. A formalin-inactivated EV71 whole virus vaccine has completed phase III trial in China but is currently unavailable clinically. The high cost of manufacturing and supply problems may limit practical implementations in developing countries. Synthetic peptides representing the native primary structure of the viral immunogen which is able to elicit neutralizing antibodies can be made readily and is cost effective. However, it is necessary to conjugate short synthetic peptides to carrier proteins to enhance their immunogenicity. This review describes the production of cross-neutralizing anti-peptide antibodies in response to immunization with synthetic peptides selected from in silico analysis, generation of B-cell epitopes of EV71 conjugated to a promiscuous T-cell epitope from Poliovirus, and evaluation of the neutralizing activities of the anti-peptide antibodies. Besides neutralizing EV71 in vitro, the neutralizing antibodies were cross-reactive against several Enteroviruses including CVA16, CVB4, CVB6, and ECHO13.

Matched MeSH terms: Antigens, Viral
Fulltext Doubly Spliced RNA of Hepatitis B Virus Suppresses Viral Transcription via TATA-Binding Protein and Induces Stress Granule Assembly

Tsai KN, Chong CL, Chou YC, Huang CC, Wang YL, Wang SW, et al.

J Virol, 2015 Nov;89(22):11406-19.
PMID: 26339052 DOI: 10.1128/JVI.00949-15

The risk of liver cancer in patients infected with the hepatitis B virus (HBV) and their clinical response to interferon alpha therapy vary based on the HBV genotype. The mechanisms underlying these differences in HBV pathogenesis remain unclear. In HepG2 cells transfected with a mutant HBV(G2335A) expression plasmid that does not transcribe the 2.2-kb doubly spliced RNA (2.2DS-RNA) expressed by wild-type HBV genotype A, the level of HBV pregenomic RNA (pgRNA) was higher than that in cells transfected with an HBV genotype A expression plasmid. By using cotransfection with HBV genotype D and 2.2DS-RNA expression plasmids, we found that a reduction of pgRNA was observed in the cells even in the presence of small amounts of the 2.2DS-RNA plasmid. Moreover, ectopic expression of 2.2DS-RNA in the HBV-producing cell line 1.3ES2 reduced the expression of pgRNA. Further analysis showed that exogenously transcribed 2.2DS-RNA inhibited a reconstituted transcription in vitro. In Huh7 cells ectopically expressing 2.2DS-RNA, RNA immunoprecipitation revealed that 2.2DS-RNA interacted with the TATA-binding protein (TBP) and that nucleotides 432 to 832 of 2.2DS-RNA were required for efficient TBP binding. Immunofluorescence experiments showed that 2.2DS-RNA colocalized with cytoplasmic TBP and the stress granule components, G3BP and poly(A)-binding protein 1 (PABP1), in Huh7 cells. In conclusion, our study reveals that 2.2DS-RNA acts as a repressor of HBV transcription through an interaction with TBP that induces stress granule formation. The expression of 2.2DS-RNA may be one of the viral factors involved in viral replication, which may underlie differences in clinical outcomes of liver disease and responses to interferon alpha therapy between patients infected with different HBV genotypes.

Matched MeSH terms: Hepatitis B e Antigens/metabolism; Hepatitis B Surface Antigens/metabolism
Fulltext Evaluation of Immunoprotection Conferred by the Subunit Vaccines of GRA2 and GRA5 against Acute Toxoplasmosis in BALB/c Mice

Ching XT, Fong MY, Lau YL

Front Microbiol, 2016;7:609.
PMID: 27199938 DOI: 10.3389/fmicb.2016.00609

Toxoplasmosis is a foodborne disease caused by Toxoplasma gondii, an obligate intracellular parasite. Severe symptoms occur in the immunocompromised patients and pregnant women leading to fatality and abortions respectively. Vaccination development is essential to control the disease. The T. gondii dense granule antigen 2 and 5 (GRA2 and GRA5) have been targeted in this study because these proteins are essential to the development of parasitophorous vacuole (PV), a specialized compartment formed within the infected host cell. PV is resistance to host cell endosomes and lysosomes thereby protecting the invaded parasite. Recombinant dense granular proteins, GRA2 (rGRA2) and GRA5 (rGRA5) were cloned, expressed, and purified in Escherichia coli, BL21 (DE3) pLysS. The potential of these purified antigens as subunit vaccine candidates against toxoplasmosis were evaluated through subcutaneous injection of BALB/c mice followed by immunological characterization (humoral- and cellular-mediated) and lethal challenge against virulent T. gondii RH strain in BALB/c mice. Results obtained demonstrated that rGRA2 and rGRA5 elicited humoral and cellular-mediated immunity in the mice. High level of IgG antibody was produced with the isotype IgG2a/IgG1 ratio of ≈0.87 (p < 0.001). Significant increase (p < 0.05) in the level of four cytokines (IFN-γ, IL-2, IL-4, and IL-10) was obtained. The antibody and cytokine results suggest that a mix mode of Th1/Th2-immunity was elicited with predominant Th1-immune response inducing partial protection against T. gondii acute infection in BALB/c mice. Our findings indicated that both GRA2 and GRA5 are potential candidates for vaccine development against T. gondii acute infection.

Matched MeSH terms: Antigens, Viral, Tumor
Amino acid sequence similarity of Hev b 3 to two previously reported 27- and 23-kDa latex proteins allergenic to spina bifida patients

Yeang HY, Ward MA, Zamri AS, Dennis MS, Light DR

Allergy, 1998 May;53(5):513-9.
PMID: 9636811

Separate studies have reported spina bifida patients to be especially allergic to proteins of 27 and 23 kDa found in the serum of centrifuged natural rubber latex. An insoluble latex protein located on the surface of small rubber particles, Hev b 3, has similarly been found to be allergenic to spina bifida patients. In this study, internal amino acid sequences of Hev b 3 showed similarity to the published sequences for the 27- and 23-kDa latex proteins. The latter allergens are hence identified as Hev b 3. Determination of the molecular weight of Hev b 3 revealed various species of 22-23 kDa. The consistent gaps of about 266 Da observed between various forms of the intact protein suggest that the protein undergoes post-translational modification. To determine whether Hev b 3 also occurs in a soluble form in the latex serum, its presence in molecular-filtered serum was checked by ELISA and Western blot. The results showed Hev b 3 to be largely absent in the C-serum from fresh latex. The protein is therefore insoluble in its native state. However, a small amount of the solubilized protein was detected in ammonia-stabilized latex (commonly used in the manufacture of latex products).

Matched MeSH terms: Antigens, Plant
Fulltext IgM capture ELISA for detection of IgM antibodies to dengue virus: comparison of 2 formats using hemagglutinins and cell culture derived antigens

Cardosa MJ, Tio PH, Nimmannitya S, Nisalak A, Innis B

Southeast Asian J. Trop. Med. Public Health, 1992 Dec;23(4):726-9.
PMID: 1298081

The highly sensitive AFRIMS format IgM capture ELISA for the diagnosis of dengue virus infections requires the use of mouse brain derived hemagglutinins and consequently also the use of 20% acetone extracted normal human serum to eliminate high background. These reagents are not always easily available and we have thus compared the AFRIMS format with another published format which uses cell culture derived antigens (culture fluid, CF, format) in order to determine if it is reasonable to use cell culture derived antigens in situations where hemagglutinins and normal human serum are difficult to obtain. The study shows that using AFRIMS results as the reference point, the CF format described here has a sensitivity of 90% and a specificity of 96%.

Matched MeSH terms: Antigens, Viral
Comparison of two IgG4 assay formats (ELISA and rapid dipstick test) for detection of brugian filariasis

Noordin R, Shenoy RK, Rahman RA

Southeast Asian J. Trop. Med. Public Health, 2003 Dec;34(4):768-70.
PMID: 15115085

Brugia malayi infection is endemic in several Asian countries. Filaria-specific IgG4 antibody detection based on BmR1 recombinant antigen has been shown to be sensitive and specific for the diagnosis of brugian filariasis. Two formats of the test has been reported ie indirect ELISA (BE) and rapid dipstick test (BR). Since different test formats use different amounts of sample and reagents which may affect its sensitivity and specificity, this study was performed to compare these two test formats in the detection of B. malayi. A total of 264 blinded serum samples from India and Malaysia were employed. Group 1 comprised 164 samples from actively infected individuals and group 2 comprised 100 samples from filaria non-endemic areas. Sensitivity was 96.3% (158/164) and 90.8% (149/164) for rapid test and ELISA respectively; chi-square p=0.00. Both test formats demonstrated 100% specificity. Therefore the rapid test format was equally specific but more sensitive than the ELISA format. The ELISA format would be able to demonstrate decline in IgG4 titer post-treatment while the rapid test would be very useful for screening and diagnosis in the field.

Matched MeSH terms: Antigens, Helminth
Fulltext Sensitized-erythrocyte-lysis (SEL) test as an epidemiological tool for human leptospirosis serological surveys

Tan DS

Bull World Health Organ, 1969;40(6):899-902.
PMID: 5307602

Epidemiological studies of human leptospirosis have generally been limited to countries with specialized laboratories employing the microscopic-agglutination (MA) test. The sensitized-erythrocyte-lysis (SEL) test is much simpler for routine hospital laboratories to carry out and it has been found valuable in the diagnosis of human leptospirosis. This paper reports the results of studies of the SEL test as an epidemiological tool in serological surveys.The results showed that the significant SEL titre was 1:80 and that the sensitivity of the test depended possibly on the antigen preparation and the amount of complement used. Most of the SEL antibodies were found to persist at significant titres for about 1 year after active infection, but less than half persisted longer than that. The SEL test is therefore useful for detecting recent infections and for indicating that stability of leptospirosis in an area.The endemicity of leptospirosis in West Malaysia was confirmed by the SEL test, based on the employment of 1:80 as the significant titre.

Matched MeSH terms: Antigens
Fulltext Combination expression of Gα12 and MAGED4B associated with poor prognosis in OSCC

Wan NurHazirah Wan Ahmad Kamil, Zuraiza Mohamad Zaini, Anand Ramanathan, Thomas Abraham, Rosnah Mohd Zain

Malaysian Journal of Medicine and Health Sciences, 2019;15(108):47-47.
MyJurnal

Introduction: Oral squamous cell carcinoma (OSCC) is a major health problem worldwide. The overall survival rate remains at 50% despite numerous studies and various treatment modalities in OSCC. The presence of lymph node metastasis in OSCC is well established as an independent prognostic factor. This present study aims to investigate the association of four tumour antigens; FJX-1, GNα12, IFITM3 and MAGED4B with the sociodemographic and clinicopathological parameters of OSCC. The potential use of these markers as a prognostic indicator of patient sur-vival and lymph node metastasis in OSCC was explored. Methods: 35 cases of OSCC with available formalin-fixed paraffin-embedded (FFPE) specimens involving the tongue, buccal mucosa, gingiva, alveolus and floor of mouth were evaluated by immunohistochemistry for FJX-1, GNA12, IFITM3 and MAGED4B expression. Assessment of the expression of these tumour antigens was based on the cellular sub-site, intensity and percentage of staining in the OSCC samples. Results: The expression of all four tumour markers were expressed in all samples (n=35) but none statistically associated with any clinicopathological or socio-demographic parameters. Survival analysis using Kaplan-Meier test showed high expression of GNA12, IFITM3 and MAGED4B individually with poor prognosis in OSCC patients. A combination of markers, GNA12 and MAGED4B demonstrated a significant association with pa-tient survival in OSCC (p=0.014). Multivariate analysis after adjustment for selected socio-demographic factors (age, gender, risk habits and sub-sites of the oral cavity) revealed that high expression of both MAGED4B and GNA12 remained as an independent prognostic factor for poor prognosis in OSCC (HRR =5.231, 95% CI 1.601,17.084; p=0.006). Conclusion: We concluded that high combined expression of both marker (Gα12 and mAGED4B) might be used as an independent prognostic indicator in OSCC.

Matched MeSH terms: Antigens, Neoplasm
Fulltext Experimental exposure of Burkholderia pseudomallei crude culture filtrate upregulates PD-1 on T lymphocytes

Menon N, Mariappan V, Vellasamy KM, Samudi C, See JX, Ganesh PS, et al.

Access Microbiol, 2020;2(5):acmi000110.
PMID: 32974575 DOI: 10.1099/acmi.0.000110

Burkholderia pseudomallei is the causative agent for melioidosis. Because of its intracellular nature, the bacterium is capable of replicating within a plethora of eukaryotic cell lines. B. pseudomallei can remain dormant within host cells without symptoms for years, causing recrudescent infections. Here, we investigated the pathogenesis mechanism behind the suppression of T cell responses by B. pseudomallei . Peripheral blood mononuclear cells (1×106 cells/well) isolated by Ficoll Paque (Sigma-Aldrich) density gradient centrifugation were incubated with optimized concentrations of bacterial crude culture filtrate antigens (CFAs) (10 ug ml-1) and heat-killed bacteria [1 : 10 multiplicity of infection (m.o.i.)]. Following incubation, cells were investigated for surface expression of coinhibitory molecules by flow cytometry. We found that B. pseudomallei induced the upregulation of programmed death 1 (PD-1), a molecule responsible for T cell exhaustion, on T cells in vitro following exposure to crude CFAs of B. pseudomallei . This upregulation of PD-1 probably contributes to poor immune surveillance and disease pathogenesis.

Matched MeSH terms: Antigens, Bacterial
Fulltext Prevalence of Red Blood Cell Alloimmunization among Transfused Chronic Kidney Disease Patients in Hospital Universiti Sains Malaysia

Yusoff SM, Bahar R, Hassan MN, Noor NHM, Ramli M, Shafii NF

Oman Med J, 2020 Sep;35(5):e177.
PMID: 33083035 DOI: 10.5001/omj.2020.95

Objectives: Red blood cell (RBC) immunization is a common complication in blood transfusion recipients. Patients with chronic kidney disease (CKD) eventually develop anemia, which is multifactorial, and requires regular blood transfusions, which exposes patients to the development of RBC antibodies. We sought to determine the prevalence and specificity patterns of RBC immunization and its risk factors among transfused CKD patients.
Methods: We conducted a cross-sectional study over one year from January to December 2018 in the Transfusion Medicine Unit, Hospital Universiti Sains Malaysia. A total of 249 samples were recruited from CKD patients who received a blood transfusion (at least one-pint), which only match for ABO and Rh(D) antigen. The serum was screened for the presence of the RBC antibody using the gel agglutination technique (Diamed gel cards). Samples with positive antibody screening were subjected to antibody identification.
Results: Of the 249 transfused CKD patients, 31 (12.4%) developed RBC immunization. Thirty (12%) were alloimmunized, and one (0.4%) was autoimmunized. Anti-Mia was the most common antibody (n = 14, 46.7%) among alloantibodies, followed by anti-E (n = 7, 23.3%). There was a significant association between pregnancy history with the development of antibodies whereas, no significant association was found between sociodemographic background, stage of CKD, hemodialysis status, underlying medical illness, and number of packed cell transfusions with the development of RBC antibodies.
Conclusions: One-eighth of our patient cohort had RBC alloimmunization, and the risk was increased in patients with a history of pregnancy. We propose Rhesus RBC phenotyping and to supply blood match Rhesus antigen in CKD patients, especially patients of reproductive age.

Matched MeSH terms: Blood Group Antigens
Fulltext Buccal swab as a suitable source of genomic DNA for screening of selected human leukocyte antigen (HLA) alleles

Vivek Prasad, Lam Yan Shim, Sethu Thakachy Subha, Fazlina Nordin, Maha Abdullah

Malaysian Journal of Medicine and Health Sciences, 2019;15(108):46-46.
MyJurnal

Introduction: Human leukocyte antigens (HLA) are a group of unique transmembrane glycoproteins that are ex-pressed on the surface of virtually all types of cells within the human body. These molecules are encoded by a set of highly polymorphic gene sequences known also as the major histocompatibility complex (MHC) and play an essential role in the presentation of antigenic peptides to immune cells for recognition and response. In recent years, various HLA alleles have been found to be associated with different autoimmune and inflammatory diseases such as rheumatoid arthritis, systemic lupus erythematosus (SLE) and allergic rhinitis. Identification of these alleles via HLA typing is necessary for initial screening and diagnosis purposes. Besides that, HLA typing is also used to determine compatibility matching between a donor and a recipient for tissue/organ transplantations in order to prevent graft rejection. Therefore, good quality and quantity of genomic DNA is required. In most scenarios, peripheral blood is chosen as the most reliable source of DNA for analysis, however this approach is seen as invasive and may cause pain and anxiety among the patients, particularly young children and weak subjects. Hence, derivation of genomic DNA from buccal cells as an alternative source material is becoming increasingly popular, especially in PCR-based genetic assays. Some of the most commonly described methods to collect buccal cells include using oral swabs, cytological brushes, mouthwashes and treated cards. Each technique yields varying quantities of DNA with diverse purity levels. In this study, we aim to evaluate the amount and purity of genomic DNA extracted from buccal swabs and brushes as well as blood for screening of selected HLA class II alleles. Methods: Cheek cell samples were col-lected using sterile foam tipped buccal swabs (Whatman) and buccal collection brushes (Gentra Puregene) whereas peripheral blood samples were withdrawn following routine venipuncture techniques. All samples were subjected to DNA extraction according to modified commercial kit protocols. Screening of selected HLA-DRB1 alleles was con-ducted via PCR with sequence-specific primers as established by Bunce et al. 1995. Results: There was no significant difference (p > 0.05) in the total DNA yield obtained from blood and buccal swab samples, which were 17.57μg (± 8.66) and 13.28μg (± 4.81), respectively. All samples exhibited similar 260/280 ratios of about ~1.80 (p > 0.05). However, buccal brush samples contributed the least amount of DNA (0.29μg, ± 0.12) compared to other sources (p < 0.05). The pure genomic DNA isolated from both blood and buccal swab samples were successfully typed for low resolution HLA-DRB1 alleles. Conclusion: Buccal swabs provide good quantity and quality of DNA for screening of HLA alleles with high accuracy and thus can be utilized as a non-invasive substitute for venipuncture.

Matched MeSH terms: HLA Antigens
Fulltext Increasing the percentage of appropriate tests conducted in the serology laboratory, Hospital Sultanah Nur Zahirah

Azlina Yahya, Osama Abdul Nasir

Q Bulletin, 2019;1(28):36-44.
MyJurnal

Wastage due to unnecessary laboratory test requests is a major problem in government hospitals because they have cost implications. Although screening of infectious marker tests such as Human Immunodeficiency Virus (HIV), Hepatitis B surface Antigen (HBsAg), Hepatitis B antibody (AHBS) and Hepatitis C Virus (HCV)) before testing have been put in place, inappropriate tests were still being carried out in the Serology laboratory, which resulted in wasted human resources and reagents, increased workload and increased maintenance costs. Based on the verification studies using the Laboratory Information System (LIS), we observed only 70% of the tests followed the ordering guidelines or test specifications. Thus, we aim to increase the standard to more than 95% of the infectious marker test requests which were appropriate according to a few guidelines.
A cross-sectional study was conducted for all infectious marker tests received at Serology Laboratory from January 2015 to June 2016 to verify the problem. A workplace audit and questionnaire survey on the staff were carried out to gain more information. Low level of knowledge, unavailability of standardised guidelines for quick and easy reference, lack of staff and inefficient work processes were among the main contributing factors. Empowering new staff to screen specimens, developing simple and informative screening guidelines, providing adequate trays and refrigerators for screening purposes and strengthening and developing a more effective process of care were the strategies taken during this study.
The appropriate tests carried out from July to September 2015, October to December 2015, January to March 2016 and April to June 2016 were 99%, 98.80%, 99.50%, 98.90% respectively. During the same period, 711, 411, 710 and 768 tests were rejected. We monitored the performance and managed to achieve 100% appropriate testing for the period of July 2016 to June 2018 and an estimation of MYR 73,437.50 cost saving was achieve

Matched MeSH terms: Hepatitis B Surface Antigens
microRNA-548m suppresses cell migration and invasion by targeting aryl hydrocarbon receptor in breast cancer cells

Nor WMFSBW, Chung I, Said NABM

Oncol Res, 2020 Oct 27.
PMID: 33109304 DOI: 10.3727/096504020X16037933185170

Breast cancer is the most commonly diagnosed cancer among women and one of the leading causes of cancer mortality worldwide, in which the most severe form happens when it metastasizes to other regions of the body. Metastasis is responsible for most treatment failures in advanced breast cancer. Epithelial-mesenchymal transition (EMT) plays a significant role in promoting metastatic processes in breast cancer. MicroRNAs (miRNAs) are highly conserved endogenous short non-coding RNAs that play a role in regulating a broad range of biological processes, including cancer initiation and development, by functioning as tumor promoters or tumor suppressors. Expression of miR-548m has been found in various types of cancers, but the biological function and molecular mechanisms of miR-548m in cancers have not been fully studied. Here, we demonstrated the role of miR-548m in modulating EMT in the breast cancer cell lines MDA-MB-231 and MCF-7. Expression data for primary breast cancer obtained from NCBI GEO datasets showed that miR-548m expression was downregulated in breast cancer patients compared with healthy group. We hypothesize that miR-548m acts as a tumor suppressor in breast cancer. Overexpression of miR-548m in both cell lines increased E-cadherin expression and decreased the EMT-associated transcription factors SNAI1, SNAI2, ZEB1 and ZEB2, as well as MMP9 expression. Consequently, migration and invasion capabilities of both MDA-MB-231 and MCF-7 cells were significantly inhibited in miR-548m-overexpressing cells. Analysis of 1059 putative target genes of miR-548m revealed common pathways involving both tight junction and the mTOR signaling pathway, which has potential impacts on cell migration and invasion. Furthermore, this study identified aryl hydrocarbon receptor (AHR) as a direct target of miR-548m in breast cancer cells. Taken together, our findings suggest a novel function of miR-548m in reversing the EMT of breast cancer by reducing their migratory and invasive potentials, at least in part via targeting AHR expression.

Matched MeSH terms: Antigens, CD
Fulltext Reticulocyte haemoglobin as a biomarker for the detection of iron deficiency anaemia in haemodialysis patients on recombinant human erythropoietin

Jamian, E., Sanip, Z., Ramli, M., Mohd Daud, K., Mohamad, S., Hassan, R.

Journal of Biomedical and Clinical Sciences, 2018;3(2):29-34.
MyJurnal

Iron deficiency anaemia (IDA) frequently occurs in haemodialysis
(HD) patients undergoing recombinant human erythropoietin (rHuEPO)
therapy and is commonly associated with rHuEPO hypo-responsiveness.
However, the conventional iron indices are inadequate to exhibit the status or
utilisation of iron during erythropoiesis. The aim of this study was to elucidate
the accuracy and usefulness of the reticulocyte haemoglobin (RET-He) test
for diagnosing IDA in HD patients undergoing rHuEPO therapy. Methods: In
this cross-sectional study, fifty-five blood samples of HD patients on rHuEPO
therapy were collected and analysed for haematological and biochemical
parameters. A receiver operating characteristics curve was also plotted for
sensitivity and specificity analysis. IDA detection rates by RET-He, soluble
transferrin receptor (sTfR) and serum ferritin were 63.64%, 3.64% and 0%,
respectively. RET-He level was significantly correlated with sTfR level, mean
cell volume, mean cell haemoglobin level and the transferrin receptor-ferritin
index. The sensitivity and specificity of RET-He in detecting IDA were 78.3%
and 92.0%, respectively, with an area under the curve of 0.864. IDA was more
frequently detected by RET-He than by ferritin or sTfR in HD patients
undergoing rHuEPO therapy. The RET-He level also showed higher sensitivity
and specificity for the iron status in these patients. Therefore, RET-He is a
useful biomarker for the detection of IDA in HD patients undergoing rHuEPO
therapy.

Matched MeSH terms: Antigens, CD
Evaluation of wound healing activity of plumbagin in diabetic rats

Shao Y, Dang M, Lin Y, Xue F

Life Sci, 2019 Aug 15;231:116422.
PMID: 31059689 DOI: 10.1016/j.lfs.2019.04.048

This study was performed to evaluate the antidiabetic and wound healing activity of plumbagin in diabetic rats by macroscopical, biochemical, histological, immunohistochemical and molecular methods. Percentage of wound closure and contraction was delayed in diabetic rats when compared to non-diabetic group. There was significant reduction in period of epithelialization, collagen and protein content. Serum insulin level was significantly lowered together with increase in glucose level in diabetic rats. Lipid levels were increased significantly with concomitant decrease in HDL level. The mRNA levels of Nrf2, collagen-1, TGF-β and α-SMA were significantly lowered whereas Keap-1 levels were increased in diabetic rats. The level of lipid peroxides was increased while the levels of antioxidants were lowered significantly. ELISA results reveal upregulated levels of inflammatory markers. Western blot result shows upregulated levels of CD68 and CD163 proteins in wound area of diabetic rats. Histopathological observation revealed increased inflammatory cells infiltration in diabetic control. Immunofluorescent staining and immunohistochemical analysis also displayed delayed wound healing in diabetic groups. Diabetic rats treated with 10% and 20% plumbagin showed increased epithelialization, collagen deposition, increased serum insulin level and increased antioxidant status. Lipid peroxides and lipid levels were lowered significantly with increase in HDL level. Inflammatory markers were lowered, and growth factors expressions were increased markedly. Thus, the results of the study indicated that plumbagin administration could improve wound healing activity and could serve as a potent antidiabetic and anti-inflammatory agent.

Matched MeSH terms: Antigens, CD

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