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1.
Malays Orthop J ; 17(2): 35-42, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37583520

ABSTRACT

Introduction: To investigate the use of a tubular retractor to provide access to the craniovertebral junction (CVJ) sparing the soft palate with the aim of reducing complications associated with traditional transoral approach but yet allowing adequate decompression of the CVJ. Materials and methods: Twelve consecutive patients with severe myelopathy (JOA-score less than 11) from ventral CVJ compression were operated between 2014-2020 using a tubular retractor assisted transoral decompression. Results: All patients improved neurologically statistically (p=0.02). There were no posterior pharynx wound infections or rhinolalia. There was one case with incomplete removal of the lateral wall of odontoid and one incidental durotomy. Conclusions: A Tubular retractor provides adequate access for decompression of the ventral compression of CVJ. As the tubular retractor pushed away the uvula, soft palate and pillars of the tonsils as it docked on the posterior pharyngeal wall, the traditional complications associated with traditional transoral procedures is completely avoided.

2.
BMC Med Ethics ; 18(1): 6, 2017 Feb 02.
Article in English | MEDLINE | ID: mdl-28148256

ABSTRACT

BACKGROUND: A cross-sectional study to ascertain what the Singapore population would regard as material risk in the anaesthesia consent-taking process and identify demographic factors that predict patient preferences in medical decision-making to tailor a more patient-centered informed consent. METHODS: A survey was performed involving patients 21 years old and above who attended the pre-operative evaluation clinic over a 1-month period in Singapore General Hospital. Questionnaires were administered to assess patients' perception of material risks, by trained interviewers. Patients' demographics were obtained. Mann-Whitney U test and Kruskal-Wallis one-way analysis of variance was used. Statistical significance was taken at p < 0.05. RESULTS: Four hundred fourteen patients were eligible of which 26 refused to participate and 24 were excluded due to language barrier. 364 patients were recruited. A higher level of education (p < 0.007), being employed (p < 0.046) and younger age group (p < 0.003) are factors identified in patients who wanted greater participation in medical decisions. Gender, marital status, type of surgery, and previous surgical history did not affect their level of participation. The complications most patients knew about were Nausea (64.8%), Drowsiness (62.4%) and Surgical Wound Pain (58.8%). Patients ranked Heart Attack (59.3%), Death (53.8%) and Stroke (52.7%) as the most significant risks that they wanted to be informed about in greater detail. Most patients wanted to make a joint decision with the anaesthetist (52.2%), instead of letting the doctor decide (37.1%) or deciding for themselves (10.7%). Discussion with the anaesthetist (61.3%) is the preferred medium of communication compared to reading a pamphlet (23.4%) or watching a video (15.4%). CONCLUSION: Age and educational level can influence medical decision-making. Despite the digital age, most patients still prefer a clinic consult instead of audio-visual multimedia for pre-operative anaesthetic counselling. The local population appears to place greater importance on rare but serious complications compared to common complications. This illustrates the need to contextualize information provided during informed consent to strengthen the doctor-patient relationship.


Subject(s)
Anesthesia/adverse effects , Communication , Decision Making , Informed Consent/standards , Patient Participation , Patient Preference , Age Factors , Anesthesiology , Cross-Sectional Studies , Death , Educational Status , Female , Health Knowledge, Attitudes, Practice , Hospitals , Humans , Male , Myocardial Infarction/etiology , Nausea/etiology , Pain/etiology , Physician-Patient Relations , Risk , Singapore , Sleep Stages , Surveys and Questionnaires
3.
J Chem Phys ; 145(23): 231101, 2016 Dec 21.
Article in English | MEDLINE | ID: mdl-28010076

ABSTRACT

Ion-molecule complexes of the form H+Arn are produced in pulsed-discharge supersonic expansions containing hydrogen and argon. These ions are analyzed and mass-selected in a reflectron spectrometer and studied with infrared laser photodissociation spectroscopy. Infrared spectra for the n = 3-7 complexes are characterized by a series of strong bands in the 900-2200 cm-1 region. Computational studies at the MP2/aug-cc-pVTZ level examine the structures, binding energies, and infrared spectra for these systems. The core ion responsible for the infrared bands is the proton-bound argon dimer, Ar-H+-Ar, which is progressively solvated by the excess argon. Anharmonic vibrational theory is able to reproduce the vibrational structure, identifying it as arising from the asymmetric proton stretch in combination with multiple quanta of the symmetric argon stretch. Successive addition of argon shifts the proton vibration to lower frequencies, as the charge is delocalized over more ligands. The Ar-H+-Ar core ion has a first solvation sphere of five argons.

4.
Int J Lab Hematol ; 38(4): 435-43, 2016 Aug.
Article in English | MEDLINE | ID: mdl-27349818

ABSTRACT

INTRODUCTION: Alpha thalassaemia is a highly prevalent disease globally and is a well-known public health problem in Malaysia. The deletional forms of the mutation are the most common forms found in alpha thalassaemia. The three most common deletional alpha thalassaemia found in this region include --(SEA) deletion, -α(3.7) rightward and -α(4.2) leftward deletions. The prevalence rate of triplication alpha cases such as ααα(anti3.7) and ααα(anti4.2) is not known in Malaysia although it plays a role in exacerbating the clinical phenotypes in beta thalassaemia carriers. Recently, there have been more reported cases of rare alpha thalassaemia mutations due to the advancement of molecular techniques involved in thalassaemia detections. Therefore, it is essential to develop a new method which allows the detection of different alpha thalassaemia mutations including the rare ones simultaneously and accurately. METHODS: The purpose of this study was to design an assay for the detection of triplications, common and rare deletional alpha thalassaemia using droplet digital PCR (ddPCR). RESULTS: This is a quantitative detection method to measure the changes of copy number which can detect deletions, duplications and triplications of the alpha globin gene simultaneously. CONCLUSION: In conclusion, ddPCR is an alternative method for rapid detection of alpha thalassaemia variants in Malaysia.


Subject(s)
High-Throughput Nucleotide Sequencing/methods , Polymerase Chain Reaction/methods , Sequence Deletion , alpha-Thalassemia/genetics , DNA Copy Number Variations , Humans , Malaysia , Molecular Epidemiology , Mutation , Phenotype , Prevalence , alpha-Thalassemia/epidemiology
5.
Genet Mol Res ; 15(2)2016 Apr 07.
Article in English | MEDLINE | ID: mdl-27173219

ABSTRACT

Hemoglobin (Hb) Adana [HBA2: c179G>A (or HBA1); p.Gly60Asp] is a non-deletional α-thalassemia variant found in Malaysia. An improvement in the molecular techniques in recent years has made identification of Hb Adana much easier. For this study, a total of 26 Hb Adana α-thalassemia intermedia and 10 Hb Adana trait blood samples were collected from patients. Common deletional and non-deletional α-thalassemia genotypes were determined using multiplex gap polymerase chain reaction (PCR) and multiplex ARMS PCR techniques. Identification of the Hb Adana location on the α-globin gene was carried out using genomic sequencing and the location of the mutation was confirmed via restriction fragment length polymorphism-PCR. Among the 36 samples, 24 (66.7%) had the -α(3.7)/α(Cd59)α mutation, while the -α(3.7)/α(Cd59)α mutation accounted for 2 samples (5.6%) and the remaining 10 (27.8%) samples were α/α(Cd59)α. All 36 samples were found to have the Hb Adana mutation on the α2-globin gene. The position of the α-globin gene mutation found in our cases was similar to that reported in Indonesia (16%) but not to that in Turkey (0.6%). Our results showed that the Hb Adana mutation was preferentially present in the α2-globin genes in Malays compared to the other ethnicities in Malaysia. Thus, the Malays might have similar ancestry based on the similarities in the Hb Adana position.


Subject(s)
Hemoglobin A/genetics , Hemoglobins, Abnormal/genetics , alpha-Thalassemia/genetics , Humans , Malaysia , Point Mutation , Polymorphism, Restriction Fragment Length , alpha-Thalassemia/ethnology
6.
Intern Med J ; 46(6): 710-6, 2016 Jun.
Article in English | MEDLINE | ID: mdl-27059930

ABSTRACT

BACKGROUND: IgE-mediated allergy to the wheat protein omega-5-gliadin (O5G) is associated with wheat-dependent exercise-induced anaphylaxis (WDEIA), where exercise acts as a cofactor, triggering anaphylaxis after wheat ingestion. The wider application of O5G-specific IgE (sIgE) testing has revealed that the manifestations of O5G allergy extend beyond WDEIA. AIMS: This study documents clinical manifestations in a large series of patients with sIgE to O5G. METHODS: A retrospective clinical audit was performed on adult patients with a positive O5G sIgE (>0.35kU/L) between 2007 and 2013 compared with a group who had negative O5G sIgE. Clinical characteristics and skin prick test (SPT) results were examined. RESULTS: Sixty-seven patients were characterised, 26 of whom presented with food-dependent exercise-induced allergy, whilst others presented with exercise-induced symptoms without apparent food association (16/67), idiopathic anaphylaxis (10/67), food-induced allergic symptoms without exercise (10/67) or recurrent acute urticaria (5/67). Specific IgE to O5G had 91% sensitivity and 92% specificity for wheat-related allergic symptoms. SPT had sensitivity of 92% and specificity of 84%. CONCLUSION: WDEIA is the most common manifestation of O5G allergy, but patients may present with a variety of allergic manifestations, and wheat allergy is not always obvious on history. Non-exercise cofactors or a lack of cofactors were identified in many patients. A distinctive feature of this allergy is that despite regular wheat ingestion, allergic reactions to wheat occur infrequently. Testing for sIgE to O5G should be considered in patients presenting with exercise-induced urticaria/anaphylaxis, idiopathic anaphylaxis and recurrent acute (but not chronic) urticaria.


Subject(s)
Allergens/immunology , Anaphylaxis/diagnosis , Antigens, Plant/immunology , Gliadin/immunology , Immunoglobulin E/blood , Wheat Hypersensitivity/diagnosis , Adult , Aged , Aged, 80 and over , Australia , Exercise , Female , Humans , Male , Middle Aged , Retrospective Studies , Sensitivity and Specificity , Skin Tests , Tryptases/blood , Urticaria/etiology , Young Adult
7.
Int J Oral Maxillofac Surg ; 45(4): 507-12, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26711249

ABSTRACT

The purpose of this study was to investigate the ophthalmic clinical findings following surgical reconstruction with autogenous bone grafts of pure blowout fractures. A retrospective review of 211 patients who underwent surgical repair of an orbital fracture between October 1996 and December 2013 was performed. Following data analysis, 60 patients who were followed up over a period of 1 year were included. A solitary floor fracture was present in 38 patients and a floor and a medial wall fracture in 22 patients. Comparing preoperative findings between these two groups, preoperative diplopia and enophthalmos were almost twice as frequent in the group with additional medial wall fractures: diplopia 8% and 14% and enophthalmos 18% and 55%, respectively. One year following surgery there was no diplopia present in either group. In the solitary floor fracture group, 3% still had enophthalmos. It can be concluded that at 1 year following the repair of pure orbital floor fractures using autogenous bone, good functional and aesthetic results can be obtained. In the group with both floor and medial wall fractures, no enophthalmos was found when both walls were reconstructed. When the medial wall was left unoperated, 29% of patients still suffered from enophthalmos after 1 year.


Subject(s)
Bone Transplantation/methods , Orbital Fractures/surgery , Plastic Surgery Procedures/methods , Adolescent , Adult , Aged , Aged, 80 and over , Esthetics , Female , Humans , Male , Middle Aged , Postoperative Complications , Treatment Outcome
8.
Arthritis Rheumatol ; 67(12): 3234-44, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26246178

ABSTRACT

OBJECTIVE: To determine the relationships between systemic sclerosis (SSc)-related autoantibodies, as well as their clinical associations, in a well-characterized Australian patient cohort. METHODS: Serum from 505 Australian SSc patients were analyzed with a commercial line immunoassay (EuroLine; Euroimmun) for autoantibodies to centromere proteins CENP-A and CENP-B, RNA polymerase III (RNAP III; epitopes 11 and 155), the 90-kd nucleolar protein NOR-90, fibrillarin, Th/To, PM/Scl-75, PM/Scl-100, Ku, topoisomerase I (topo I), tripartite motif-containing protein 21/Ro 52, and platelet-derived growth factor receptor. Patient subgroups were identified by hierarchical clustering of the first 2 dimensions of a principal components analysis of quantitative autoantibody scores. Results were compared with detailed clinical data. RESULTS: A total of 449 of the 505 patients were positive for at least 1 autoantibody by immunoblotting. Heatmap visualization of autoantibody scores, along with principal components analysis clustering, demonstrated strong, mutually exclusive relationships between CENP, RNAP III, and topo I. Five patient clusters were identified: CENP, RNAP III strong, RNAP III weak, topo I, and other. Clinical features associated with CENP, RNAP III, and topo I were consistent with previously published reports concerning limited cutaneous and diffuse cutaneous SSc. A novel finding was the statistical separation of RNAP III into 2 clusters. Patients in the RNAP III strong cluster had an increased risk of gastric antral vascular ectasia, but a lower risk of esophageal dysmotility. Patients in the other cluster were more likely to be male and to have a history of smoking and a history of malignancy, but were less likely to have telangiectasia, Raynaud's phenomenon, and joint contractures. CONCLUSION: Five major autoantibody clusters with specific clinical and serologic associations were identified in Australian SSc patients. Subclassification and disease stratification using autoantibodies may have clinical utility, particularly in early disease.


Subject(s)
Autoantibodies/immunology , Scleroderma, Systemic/immunology , Aged , Antigens, Nuclear/immunology , Australia , Autoantigens/immunology , Centromere Protein A , Centromere Protein B/immunology , Chromosomal Proteins, Non-Histone/immunology , Cohort Studies , Contracture/etiology , Contracture/immunology , DNA Topoisomerases, Type I/immunology , DNA-Binding Proteins/immunology , Esophageal Motility Disorders/etiology , Esophageal Motility Disorders/immunology , Exoribonucleases/immunology , Exosome Multienzyme Ribonuclease Complex/immunology , Female , Gastric Antral Vascular Ectasia/etiology , Gastric Antral Vascular Ectasia/immunology , Humans , Immunoblotting , Ku Autoantigen , Male , Middle Aged , Neoplasms/epidemiology , Pol1 Transcription Initiation Complex Proteins/immunology , Principal Component Analysis , RNA Polymerase III/immunology , RNA-Binding Proteins/immunology , Raynaud Disease/etiology , Raynaud Disease/immunology , Receptors, Platelet-Derived Growth Factor/immunology , Ribonucleoproteins/immunology , Scleroderma, Systemic/complications , Scleroderma, Systemic/epidemiology , Sex Factors , Smoking/epidemiology , Telangiectasis/etiology , Telangiectasis/immunology
9.
BMJ Open ; 5(7): e007648, 2015 Jul 22.
Article in English | MEDLINE | ID: mdl-26201722

ABSTRACT

OBJECTIVES: Single nucleotide polymorphism (SNP) with a mutation can be used to identify the presence of the paternally-inherited wild-type or mutant allele as result of the inheritance of either allele in the fetus and allows the prediction of the fetal genotype. This study aims to identify paternal SNPs located at the flanking regions upstream or downstream from the ß-globin gene mutations at CD41/42 (HBB:c.127_130delCTTT), IVS1-5 (HBB:c.92+5G>C) and IVS2-654 (HBB:c.316-197C>T) using free-circulating fetal DNA. SETTING: Haematology Lab, Department of Biomedical Science, University of Malaya. PARTICIPANTS: Eight couples characterised as ß-thalassaemia carriers where both partners posed the same ß-globin gene mutations at CD41/42, IVS1-5 and IVS2-654, were recruited in this study. OUTCOME MEASURES: Genotyping was performed by allele specific-PCR and the locations of SNPs were identified after sequencing alignment. RESULTS: Genotype analysis revealed that at least one paternal SNP was present for each of the couples. Amplification on free-circulating DNA revealed that the paternal mutant allele of SNP was present in three fcDNA. Thus, the fetuses may be ß-thalassaemia carriers or ß-thalassaemia major. Paternal wild-type alleles of SNP were present in the remaining five fcDNA samples, thus indicating that the fetal genotypes would not be homozygous mutants. CONCLUSIONS: This preliminary research demonstrates that paternal allele of SNP can be used as a non-invasive prenatal diagnosis approach for at-risk couples to determine the ß-thalassaemia status of the fetus.


Subject(s)
DNA, Intergenic/genetics , DNA/analysis , Fetus/metabolism , Prenatal Diagnosis/methods , beta-Globins/genetics , beta-Thalassemia/diagnosis , Female , Genetic Carrier Screening , Homozygote , Humans , Male , Polymorphism, Single Nucleotide , Pregnancy , beta-Thalassemia/genetics
10.
Int J Lab Hematol ; 37(1): 79-89, 2015 Feb.
Article in English | MEDLINE | ID: mdl-24725998

ABSTRACT

INTRODUCTION: In Malaysia, ß-thalassaemia is a common inherited blood disorder in haemoglobin synthesis with a carrier rate of 4.5%. Currently, PCR-incorporating techniques such as amplification refractory mutation system (ARMS) or reverse dot blot hybridization (RDBH) are used in ß-thalassaemia mutation detection. ARMS allows single-mutation identification using two reactions, one for wild type and another for mutant alleles. RDBH requires probe immobilization and optimization of hybridization and washing temperatures which is time consuming. The aim of our study was to investigate whether ß-thalassaemia mutations can be identified in samples with low DNA concentrations. METHODS: Genotype identification of common ß-thalassaemia mutations in Malays was carried out using Taqman genotyping assays. RESULTS: Results show that the Taqman assays allow mutation detection with DNA template concentrations as low as 2-100 ng. In addition, consistent reproducibility was observed in the Taqman assays when repeated eight times and at different time intervals. CONCLUSION: The developed sensitive Taqman assays allow molecular characterization of ß-thalassaemia mutations in samples with low DNA concentrations. The Taqman genotyping assays have potential as a diagnostic tool for foetal blood, chorionic villi or pre-implantation genetic diagnosis where DNA is limited and precious.


Subject(s)
Mutation , Real-Time Polymerase Chain Reaction , beta-Globins/genetics , beta-Thalassemia/diagnosis , beta-Thalassemia/genetics , Alleles , Genotype , Genotyping Techniques , Humans , Malaysia , Real-Time Polymerase Chain Reaction/methods , Real-Time Polymerase Chain Reaction/standards , Reproducibility of Results , Sensitivity and Specificity
11.
Br J Anaesth ; 114(1): 63-9, 2015 Jan.
Article in English | MEDLINE | ID: mdl-24980424

ABSTRACT

BACKGROUND: The ideal thromboprophylaxis in patients at risk of bleeding is uncertain. This retrospective cohort study assessed the risk factors for complications after using retrievable inferior vena cava (IVC) filters for primary or secondary thromboembolism prophylaxis in patients after major trauma. METHODS: Using data from radiology, trauma and death registries, the incidence of and risk factors for subsequent deep venous thrombosis (DVT), venous thromboembolism (VTE), and mechanical complications related to retrievable IVC filters in patients, admitted between 2007 and 2012, were assessed in a single trauma centre. RESULTS: Of the 2940 major trauma patients admitted during the study period, a retrievable IVC filter was used in 223 patients (7.6%). Thirty-six patients (16%) developed DVT or VTE subsequent to placement of IVC filters (median 20 days, interquartile range 9-33), including 27 with lower limb (DVT), 8 upper limb DVT, and 4 pulmonary embolism. A high Injury Severity Score, tibial/fibular fractures, and a delay in initiating pharmacological thromboprophylaxis after insertion of the filters (14 vs 7 days, P=0.001) were significant risk factors. Thirty patients were lost to follow-up (13%) and their filters were not retrieved. Mechanical complications-including filters adherent to the wall of IVC (4.9%), IVC thrombus (4.0%), and displaced or tilted filters (2.2%)-were common when the filters were left in situ for >50 days. CONCLUSIONS: A delay in initiating pharmacological thromboprophylaxis or filter removal were associated with an increased risk of subsequent DVT, VTE, and mechanical complications of retrievable IVC filters in patients after major trauma.


Subject(s)
Device Removal/adverse effects , Pulmonary Embolism/epidemiology , Vena Cava Filters/adverse effects , Venous Thromboembolism/epidemiology , Venous Thrombosis/epidemiology , Wounds and Injuries/epidemiology , Adult , Cohort Studies , Comorbidity , Equipment Failure , Female , Follow-Up Studies , Humans , Male , Middle Aged , Pulmonary Embolism/etiology , Retrospective Studies , Risk Factors , Severity of Illness Index , Time Factors , Venous Thromboembolism/etiology , Venous Thrombosis/etiology , Western Australia/epidemiology , Wounds and Injuries/surgery , Young Adult
12.
Anaesth Intensive Care ; 41(3): 322-7, 2013 May.
Article in English | MEDLINE | ID: mdl-23659393

ABSTRACT

Thrombocytopenia or an abnormal coagulation profile is not rare in hospitalised patients who have symptoms consistent with acute pulmonary embolism (PE). Theoretically, coagulopathy is more likely to occur in patients with pneumonia than acute PE. This study aimed to assess whether the presence of coagulopathy could be used to exclude acute PE in patients with symptoms and signs consistent with acute PE. In this study, a significant coagulopathy was defined as a platelet count <100×10(9)/l, an international normalised ratio >1.5, or activated partial thromboplastin time >50 seconds. Patients treated with systemic anticoagulants prior to computed tomography pulmonary angiography were excluded. Of the 986 consecutive patients who required computed tomography pulmonary angiography to exclude acute PE over a four-month period in five hospitals in Western Australia, acute PE was confirmed in 149 patients (15.1%). The incidence of coagulopathy was not significantly different between those with and without acute PE (4 vs 7%, respectively; P=0.161) and between those with and without pneumonia (8 vs 7%, respectively; P=0.505). Positive and negative likelihood ratios of coagulopathy in differentiating acute PE or pneumonia were both unsatisfactory. As a continuous predictor, platelet counts, international normalised ratio, activated partial thromboplastin time and plasma fibrinogen concentrations were also not useful in differentiating between acute PE and other pulmonary pathologies (areas under the receiver operating characteristic curve were all close to 0.5). In conclusion, the presence of significant acquired coagulopathy cannot be used to suggest pneumonia or exclude symptomatic acute PE when the prevalence or pre-test probability of acute PE is not low.


Subject(s)
Blood Coagulation Disorders/blood , Pulmonary Embolism/diagnosis , Acute Disease , Aged , Angiography , Blood Coagulation Disorders/mortality , Cohort Studies , Female , Fibrin Fibrinogen Degradation Products/analysis , Humans , International Normalized Ratio , Male , Middle Aged , Partial Thromboplastin Time , Platelet Count , Pulmonary Embolism/mortality , Retrospective Studies , Tomography, X-Ray Computed
13.
Genet Mol Res ; 12(3): 2409-15, 2013 Jul 15.
Article in English | MEDLINE | ID: mdl-23479149

ABSTRACT

Beta-thalassemia is a life-threatening inherited blood disorder. Rapid characterization of ß-globin gene mutations is necessary because of the high frequency of Malaysian ß-thalassemia carriers. A combination real-time polymerase chain reaction genotyping assay using TaqMan probes was developed to confirm ß-globin gene mutations. In this study, primers and probes were designed to specifically identify 8 common ß-thalassemia mutations in the Malaysian Malay and Chinese ethnic groups using the Primer Express software. "Blind tests" using DNA samples from healthy individuals and ß-thalassemia patients with different genotypes were performed to determine the specificity and sensitivity of this newly designed assay. Our results showed 100% sensitivity and specificity for this novel assay. In conclusion, the TaqMan genotyping assay is a straightforward assay that allows detection of ß-globin gene mutations in less than 40 min. The simplicity and reproducibility of the TaqMan genotyping assay permit its use in laboratories as a rapid and cost-effective diagnostic tool for confirmation of common ß-thalassemia mutations in Malaysia.


Subject(s)
Asian People/genetics , Genotyping Techniques/methods , Mutation , beta-Thalassemia/genetics , Asian People/ethnology , Case-Control Studies , Haptoglobins/genetics , Humans , Malaysia , Polymerase Chain Reaction/methods , Sensitivity and Specificity , Single-Blind Method , beta-Thalassemia/ethnology
14.
West Indian Med J ; 61(6): 569-73, 2012 Sep.
Article in English | MEDLINE | ID: mdl-23441349

ABSTRACT

OBJECTIVE: To determine the activity of paraoxonase 1 (PON1) in keratoconus in a Malaysian population in comparison with non-keratoconic subjects. METHODS: Clinical eye examinations were performed on patients with keratoconus and non-keratoconic subjects after questionnaires were completed. Blood samples were collected and subjected to spectrophotometric analysis of paraoxonase and diazoxonase activities for the determination of the status of PON1 of every individual. RESULTS: Of the 11 keratoconic patients and 55 non-keratoconic control samples collected, eight patients of Indian ethnicity were keratoconic (73%), whereas 33 non-Indians were non-keratoconic (60%; p = 0.047). Paraoxonase activity was lower in Indians compared to the non-Indians ie Malays and Chinese (p = 0.008). Keratoconic subjects had a lower paraoxonase activity compared to non-keratoconics (p = 0.038). CONCLUSIONS: The reduced paraoxonase activity in keratoconic patients suggests that the keratoconic corneas were more susceptible to oxidative stress. Reduced paraoxonase activity and keratoconus status appears to be associated with ethnicity.


Subject(s)
Aryldialkylphosphatase/blood , Keratoconus/enzymology , Adolescent , Adult , Aryldialkylphosphatase/genetics , Asian People , Case-Control Studies , Female , Genotype , Humans , Keratoconus/ethnology , Keratoconus/genetics , Male , Middle Aged , Polymorphism, Genetic , White People , Young Adult
15.
West Indian Med J ; 60(1): 3-8, 2011 Jan.
Article in English | MEDLINE | ID: mdl-21809703

ABSTRACT

Beta-thalassaemia major causes severe anaemia and patients with it may be transfusion-dependent for life. Regular blood transfusions cause iron-overload that leads to oxidative damage which can hasten mortality. The objective of this research was to study the oxidant-antioxidant indices in beta-thalassaemia major patients at the University of Malaya Medical Centre (UMMC) who were on desferrioxamine-chelation or without chelation therapy. Blood was collected from 39 Chinese patients and 20 controls. Plasma and peripheral blood mononuclear cell lysates (PBMC) were extracted and biochemical tests to evaluate oxidative stress were performed. Oxidative stress was evident in these patients as advanced oxidized protein products (AOPP) and lipid hydroperoxides were elevated, whereas glutathione peroxidase activity and the ferric reducing antioxidant power (FRAP) were reduced. The catalase activity in the patients' PBMC was elevated, possibly as a compensatory mechanism for the reduced glutathione peroxidase activity in both red blood cells and PBMC. The lower FRAP and higher AOPP levels in the non-chelated patients compared with the chelated patients were indicative of a lower oxidative stress level in the chelated patients. The ferritin levels in the chelated and non-chelated patients were high and the mean levels of liver enzyme activities in the majority of patients were elevated regardless of chelation therapy. In conclusion, this study indicates that desferrioxamine chelation therapy does not normalize ferritin level but attenuates oxidative damage and improves total antioxidant level in Malaysian Chinese beta-thalassaemia major patients.


Subject(s)
Chelation Therapy/methods , Deferoxamine/therapeutic use , Ferritins/blood , Siderophores/therapeutic use , beta-Thalassemia/blood , beta-Thalassemia/drug therapy , Adolescent , Analysis of Variance , Case-Control Studies , Child , China/ethnology , Female , Glutathione Peroxidase/blood , Humans , Lipid Peroxides/blood , Malaysia , Male , Oxidative Stress/drug effects , Xanthine Oxidase/blood , beta-Thalassemia/enzymology
16.
Br J Anaesth ; 106(4): 528-36, 2011 Apr.
Article in English | MEDLINE | ID: mdl-21335622

ABSTRACT

BACKGROUND: The role of corticosteroids in severe sepsis and pneumonia remains controversial. This study described the use of L'Abbé and pooled calibration plots to assess the relationship between severity of illness and effectiveness of corticosteroids for severe sepsis. METHODS: Randomized controlled trials (RCTs) comparing corticosteroids and placebo from Cochrane Controlled Trial Register, MEDLINE, and EMBASE databases were retrieved. The observed and predicted mortality rates of the placebo groups were used as a measure of the severity of illness of the patients in L'Abbé and calibration plots. RESULTS: A total of 1089 patients from 10 RCTs fulfilled the inclusion criteria and were subject to further analysis. L'Abbé and calibration plots did not suggest significant interactions between the effectiveness of corticosteroids and severity of illness. The pooled calibration plot suggested that the mortality rates of the placebo groups from three studies were higher than predicted. After excluding these studies in the meta-analysis, there was a reduction in the point estimate of benefit of corticosteroids on mortality [odds ratio (OR) 0.97, 95% confidence interval (CI): 0.71-1.33, P=0.87 by a fixed-effect model, P=0.59 by a random-effects model vs OR 0.85, 95% CI: 0.66-1.10%]. CONCLUSIONS: The pooled calibration plot suggested that there were excessive deaths in the placebo groups of some RCTs that could explain the apparent benefit of corticosteroids on mortality of patients with severe sepsis. L'Abbé and pooled calibration plots might be useful as adjuncts to assess interactions between severity of illness and effectiveness of an intervention.


Subject(s)
Glucocorticoids/therapeutic use , Sepsis/drug therapy , Severity of Illness Index , Adult , Aged , Humans , Middle Aged , Pneumonia/drug therapy , Randomized Controlled Trials as Topic , Sepsis/mortality , Treatment Outcome , Young Adult
17.
Med J Malaysia ; 66(5): 429-34, 2011 Dec.
Article in English | MEDLINE | ID: mdl-22390095

ABSTRACT

Detection and quantification of Hb subtypes of human blood is integral to presumptive identification of thalassaemias. It has been used in neonatal screening of thalassaemia and Hb variants. The use of discarded red blood cells following processing of the cord blood for stem cells provides readily available diagnostic material for thalassaemia screening. In this study, we determined the range of Hb subtypes in 195 consecutive cord blood samples collected for cord blood banking. The 'cord blood samples' analysed were those of the remaining red blood cells after the cord blood was processed for stem cell storage. Quantification of Hb subtypes by high performance liquid chromatography (HPLC) was done on BioRad Variant II Hb testing system. Only 73 (36.5%) of the samples could be analyzed neat without dilution. With a 1:300 dilution with wash solution the acceptable area as recommended by the manufacturer for reading of a C-gram within the 1 to 3 million ranges were achieved in all. Eighteen (9%) 12 showed classical Hb Barts (y4) prerun peaks were confirmed by Sebia Hydrasys automated Hb gel electrophoresis and quantified by Sebia Capillarys 2 capillary electrophoresis. Only 1 (0.5%) was presumptively identified with HbH disease. Due to the limited number of samples no beta-thalassaemia major, Hb E beta-thalassaemia and Hb Barts hydrops fetalis were found. The HPLC assay was possible at a cost US$ 5 per sample and a turnover time of 10 samples per hour without technical difficulties. This study reports an effective and valuable protocol for thalassaemia screening in red blood cells which would otherwise be discarded during cord blood processing. Cord blood with severe and intermediate forms of thalassaemia can be preselected and not stored.


Subject(s)
Erythrocytes , Neonatal Screening/methods , Thalassemia/diagnosis , Chromatography, High Pressure Liquid , Electrophoresis/methods , Feasibility Studies , Fetal Blood , Humans , Infant, Newborn , Neonatal Screening/instrumentation , Thalassemia/blood
18.
Anaesthesia ; 64(12): 1342-52, 2009 Dec.
Article in English | MEDLINE | ID: mdl-19849681

ABSTRACT

This meta-analysis examined the benefits of using remifentanil as a sedative agent in critically ill patients. A total of 11 randomised controlled trials, comparing remifentanil with another opioid or hypnotic agent in 1067 critically ill adult patients, were identified from the Cochrane controlled trials register and EMBASE and MEDLINE databases, and subjected to meta-analysis. Remifentanil was associated with a reduction in the time to tracheal extubation after cessation of sedation (weighted-mean-difference -2.04 h (95% CI -0.39 to -3.69 h); p = 0.02). Remifentanil was, however, not associated with a significant reduction in mortality (relative risk 1.01 (95% CI 0.67-1.52); p = 0.96), duration of mechanical ventilation, length of intensive care unit stay, and risk of agitation (relative risk 1.08 (95% CI 0.64-1.82); p = 0.77) when compared to an alternative sedative or analgesic agent. The current evidence does not support the routine use of remifentanil as a sedative agent in critically ill adult patients.


Subject(s)
Conscious Sedation/methods , Critical Illness/therapy , Hypnotics and Sedatives , Piperidines , Adult , Humans , Randomized Controlled Trials as Topic/methods , Remifentanil
19.
Community Genet ; 11(3): 129-34, 2008.
Article in English | MEDLINE | ID: mdl-18376108

ABSTRACT

BACKGROUND/AIMS: Individuals with double heterozygosity for alpha- and beta-thalassaemia and heterozygous beta-thalassaemia show a similar haematological picture. Co-inheritance of alpha- and beta-thalassaemia in both partners may result in pregnancies with either Hb Bart's hydrops foetalis or beta-thalassaemia major, or pregnancies with both disorders. METHODS: The co-inheritance of alpha-thalassaemia in 322 beta-thalassaemia carriers in Malaysia was studied. RESULTS: The frequency of alpha-thalassaemia in the beta-thalassaemia carriers was 12.7% (41/322), with a carrier frequency of 7.8% for the SEA deletion, 3.7% for the -alpha(3.7) deletion, 0.9% for Hb Constant Spring and 0.3% for the -alpha(4.2) deletion. CONCLUSION: Double heterozygosity for alpha- and beta-thalassaemia was confirmed in 5 out of the 41 couples and the risk of the fatal condition Hb Bart's hydrops foetalis was confirmed in two of these couples. Detection of the Southeast Asian (SEA) deletion in the Malaysian Malays in this study confirms that Hb Bart's hydrops foetalis can occur in this ethnic group. Results of this study have provided new information on the frequency and different types of alpha-thalassaemia (--(SEA), -alpha(3.7) and -alpha(4.2) deletions, Hb Constant Spring) in Malaysian beta-thalassaemia carriers.


Subject(s)
alpha-Thalassemia/genetics , beta-Thalassemia/genetics , Asian People/genetics , China/ethnology , Female , Genetic Linkage , Heterozygote , Humans , India/ethnology , Inheritance Patterns/genetics , Malaysia/epidemiology , Male , Pregnancy , Prenatal Diagnosis , Retrospective Studies , alpha-Thalassemia/diagnosis , alpha-Thalassemia/ethnology , beta-Thalassemia/diagnosis , beta-Thalassemia/ethnology
20.
Med J Malaysia ; 61(2): 217-20, 2006 Jun.
Article in English | MEDLINE | ID: mdl-16898315

ABSTRACT

Thalassaemia is an inherited blood disorder and is a significant public health problem in Malaysia, with many not knowing they carry the gene for thalassaemia. The two major forms are alpha and beta thalassaemia. An individual can co-inherit both the alpha and beta thalassaemia genes. This study determined the frequency of concurrent carriers of alpha thalassaemia in 231 beta thalassaemia carriers. Gap-PCR was done on extracted DNA of the beta thalassaemia samples to check for alpha thalassaemia 1 molecular defect. Eight (3.5%) samples were found to have concurrently inherited the alpha thalassaemia 1 (- -SEA) deletion. The significant carrier rate for alpha thalassaemia 1 indicates the need for the implementation of DNA analysis to complement thalassaemia screening in high risk populations.


Subject(s)
DNA/analysis , Genetic Testing/methods , alpha-Thalassemia/epidemiology , beta-Thalassemia/epidemiology , Chromatography, High Pressure Liquid , Genetic Predisposition to Disease , Hemoglobins/metabolism , Humans , Malaysia/epidemiology , Polymerase Chain Reaction , Prevalence , alpha-Thalassemia/complications , alpha-Thalassemia/genetics , beta-Thalassemia/complications , beta-Thalassemia/genetics
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