Methylenetetrahydrofolate reductase gene C677T and A1298C polymorphisms, plasma homocysteine, folate, and vitamin B12 levels and the extent of coronary artery disease

The question of whether mild hyperhomocysteinemia is a risk factor for coronary artery disease (CAD) has long been debated and is still unclear. We investigated whether there is a link between methylenetetrahydrofolate reductase (MTHFR) gene C677T and A1298C polymorphisms or plasma homocysteine and CAD. This is a case-control study that included 2,121 consecutive patients (cases) with angiographically proved CAD and 617 patients without CAD (controls). MTHFR gene C677T and A1298C polymorphisms, plasma homocysteine, folate, and vitamin B(12) concentrations were determined and coronary angiography was performed in all subjects. The distribution of MTHFR gene C677T genotypes in patients (or controls) was: CC-genotype in 915 cases, 43.1% (266 controls, 43.1%); CT-genotype in 955 cases, 45.0%, (283 controls, 45.9%); and TT-genotype in 251 cases, 11.9% (68 controls, 11.0%) (p = 0.84). The distribution of MTHFR gene A1298C genotypes in patients (or controls) was: AA-genotype in 973 cases, 45.9% (281 controls, 45.5%); AC-genotype in 905 cases, 42.7% (284 controls, 46.0%); and CC-genotype in 243 cases, 11.4% (52 controls, 8.5%) (p = 0.07). Patients with CAD had higher levels of plasma homocysteine (12.9 +/- 5.1 vs 11.9 +/- 4.5 micromol/L, p <0.001) and lower levels of folate (9.5 +/- 3.1 vs 9.9 +/- 3.8 ng/ml, p = 0.008) than controls. After adjustment for other risk factors for CAD, plasma homocysteine (p = 0.89), MTHFR gene C677T (p = 0.38), or A1298C polymorphisms (p = 0.13) were not independent correlates of CAD. This study demonstrated that MTHFR gene C677T or A1298C polymorphisms are not associated with the presence of angiographic CAD. Although there is an apparent association between elevated levels of homocysteine and CAD, this association is not independent of conventional cardiovascular risk factors.     

Reversible airway obstruction in rheumatic mitral valve disease

Lung function was studied in 24 patients with advanced mitral stenosis scheduled for mitral valve replacement (MVR), and revealed an obstructive ventilatory pattern [rewording of this sentence OK] . Forty per cent of the patients had a forced expiratory volume in 1 s (FEV₁)<60% of that predicted in the preoperative period. Twenty-five per cent of those operated upon showed a similar pattern up to 110 weeks postoperatively. A blind study of the effect of placebo and β₂ agonist (salbutamol) inhalation was performed preoperatively and 6 months postoperatively, to evaluate the reversibility of airflow obstruction in these patients, flow volume curve and body plethysmographic measurement of airway resistance (Rex) and intrathoracic gas volume (VTG). Patients in the pre and postoperative period showed a significant difference between the placebo and the β₂ agonist responses for FEV₁, FEV₁ as percentage of FVC (FEV₁% FVC), peak expiratory flow rate (PEFR), flow rate of 50% of expiratory vital capacity ([¨max₅₀), Rex and VTG (P<0.001). We conclude that salbutamol inhalation improves obstructive impairment in patients with MVR pre- and postoperatively.     

Relation between plasma fibroblast growth factor-23, serum fetuin-A levels and coronary artery calcification evaluated by multislice computed tomography in patients with normal kidney function

Objective To examine the correlation of plasma fibroblast growth factor (FGF)‐23 and serum fetuin A levels with the coronary artery calcification score (CACS) in patients with normal kidney function. Background Vascular calcification is an active process that may be aggravated by hyperphosphataemia and hypercalcaemia. FGF‐23 and human fetuin‐A have been associated with calcifying arteriosclerosis in renal failure. Plasma FGF‐23 was identified as an independent factor negatively associated with peripheral vascular calcification. Fetuin‐A acts as a systemic inhibitor of ectopic calcification in dialysis patients and can be correlated to the survival of these patients. Very few data exists on the role of FGF‐23 and fetuin‐A in coronary calcification of patients without impaired kidney function. Materials and methods Sixty‐four patients, 21 females and 43 males, were subjected to 64‐slice coronary computed tomography (CT) to evaluate coronary artery calcification (CAC). Plasma intact FGF‐23 was determined by ELISA. Serum fetuin‐A concentration were evaluated nephelometrically. Results Mean plasma FGF‐23 level was 20·4 ± 9·1 pg/ml and serum fetuin‐A was 0·46 ± 0·09 g/l. There was no correlation between FGF‐23 (P = 0·777) and fetuin‐A (P = 0·767) levels and the CACS. No correlation was found between the presence of noncalcified plaques and coronary artery stenosis (CAS) ≥  50%, and FGF‐23 (P = 0·313 and P = 0·775) and fetuin‐A levels (P = 0·601 and P = 0·659). Conclusion Plasma intact FGF‐23 and serum fetuin‐A concentration do not correlate with the CACS, the grade of stenosis or presence of noncalcified plaques of the coronary arteries in patients with normal kidney function.     

Short communication: use of a recombinant antigen-based ELISA to determine prevalence of brugian filariasis among Malaysian schoolchildren near Pasir Mas,Kelantan-Thailand border

Brugian filariasis infects 13 million people in Asia. The routine prevalence survey method using night thick blood smear is not sensitive enough to reflect the actual infection prevalence. In 1997-2001, only three microfilaraemic cases (of 5601 individuals screened; 0.05%) were reported in Pasir Mas, a district in Kelantan (Malaysia), which shares a border with Thailand. We therefore investigated the infection prevalence in this district by employing a sensitive and specific serological assay (Brugia-Elisa). This test is based on detection of specific IgG4 antibody against a Brugia malayi recombinant antigen. A total of 5138 children, aged 7-12 years, from 16 primary schools, were tested. Eighteen pupils in eight schools, located in five subdistricts, tested positive, giving an overall prevalence rate of 0.35%. Infection in these children is significant as they represent more recent cases. These subdistricts should be included in the national filariasis elimination programme.     

Age is not a predictor of patent foramen ovale with right-to-left shunt in patients with cerebral ischemic events

BACKGROUND: Patent foramen ovale (PFO) with or without atrial septal aneurysm (ASA) is highly associated with cerebral ischemic events in young patients. The prevalence of PFO and ASA in elderly patients with cerebral ischemic events is not well described. OBJECTIVE: Our study is to evaluate the frequencies of PFO with right-to-left shunt (RLS) and ASA in elderly patients and to determine whether age is a predictor of flow-reversed PFO with RLS in cerebral ischemic events. METHODS: A prospective registry for all consecutive patients with cerebral ischemic events who were evaluated by transesophageal echocardiography (TEE) for the detection of possible cardiac source of embolization was established and maintained in a university hospital. Patients' demographics including age, gender, ethnic origin, cerebrovascular risk factors, and all positive TEE data were collected from July 2000 to August 2001 for statistical analysis. A univariate and multivariate stepwise logistic regression analysis was performed. RESULTS: In older patients the prevalence of PFO with RLS, PFO, and ASA was 25/118 (20%), 28/118 (24%), and 38/118 (32%), respectively, as opposed to younger patients, in whom it was 35/119 (30%), 39/119 (33%), and 38/119 (32%), respectively. Older patients had higher frequencies of hypertension (59; 69%), CAD (25; 21%), and prior history of stroke (23; 20%) as opposed to younger patients. Younger age (<60 years), gender, smoking history, hypertension, hyperlipidemia, CAD, and prior history of stroke were not associated with higher prevalence of PFO with RLS. Patent foramen ovale was associated with ASA (P < 0.001) and LVH (P < 0.019) in patients with TIA and stroke. In multivariate analysis only ASA (P < 0.001) remained significant with PFO, with RLS controlling for age, gender, and LVH. CONCLUSIONS: PFO with RLS and ASA are frequently present in elderly stroke and/or TIA patients and age is not a predictor for PFO. Transesophageal echocardiography should be considered for all stroke and/or TIA patients irrespective of their age.     

The Essence of Accommodating Older Adults into the Social Care Sector in Malaysia

Population ageing puts pressure on the workforce and increase the demands for aged workforce. The demographic shifts have made the issue of healthier workers, especially those of advanced age and physically related job scopes, a fundamental aspect to employing older workers. Hence, this study aimed to explore the best practices to employ older adults into the social care sector. The social care sector was chosen in view of the nature of job and declining demand among younger workers. A qualitative study was conducted involving series of focus group discussions (FGD) with social care workers of long-term care centers in the peninsular Malaysia. Data was collected using a validated and pre-tested semi-structured interview protocol. Each focus group discussions and in-depth interviews were lasted between 45 min to 1 h. A total of 57 workers were consented for the study which was divided into young and old workers based on the mean age of 41.43 [SD ± 9.97] years old. The content of the interviews was transcribed verbatim and thematic analysis was performed to inductively identify the coding and themes within the data related to the challenges employing older workers into the social care sector. Three categories of coding were identified (individual, environmental and management factors), leading to the identification of two important themes which are healthy workplace and work autonomy. The findings indicate the needs for work culture transformations to cultivate healthy working environment and freedom of speech particularly among the older workers.     

Nebulin (NEB) mutations in a childhood onset distal myopathy with rods and cores uncovered by next generation sequencing

Recessive nebulin (NEB) mutations are a common cause of nemaline myopathy (NM), typically characterized by generalized weakness of early-onset and nemaline rods on muscle biopsy. Exceptional adult cases with additional cores and an isolated distal weakness have been reported. The large NEB gene with 183 exons has been an obstacle for the genetic work-up. Here we report a childhood-onset case with distal weakness and a core-rod myopathy, associated with recessive NEB mutations identified by next generation sequencing (NGS). This 6-year-old boy presented with a history of gross-motor difficulties following a normal early development. He had distal leg weakness with bilateral foot drop, as well as axial muscle weakness, scoliosis and spinal rigidity; additionally he required nocturnal respiratory support. Muscle magnetic resonance (MR) imaging showed distal involvement in the medial and anterior compartment of the lower leg. A muscle biopsy featured both rods and cores. Initial targeted testing identified a heterozygous Nebulin exon 55 deletion. Further analysis using NGS revealed a frameshifting 4 bp duplication, c.24372_24375dup (P.Val8126fs), on the opposite allele. This case illustrates that NEB mutations can cause childhood onset distal NM, with additional cores on muscle biopsy and proves the diagnostic utility of NGS for myopathies, particularly when large genes are implicated.     

RyR1 Deficiency in Congenital Myopathies Disrupts Excitation–Contraction Coupling

In skeletal muscle, excitation–contraction (EC) coupling is the process whereby the voltage‐gated dihydropyridine receptor (DHPR) located on the transverse tubules activates calcium release from the sarcoplasmic reticulum by activating ryanodine receptor (RyR1) Ca²⁺ channels located on the terminal cisternae. This subcellular membrane specialization is necessary for proper intracellular signaling and any alterations in its architecture may lead to neuromuscular disorders. In this study, we present evidence that patients with recessive RYR1‐related congenital myopathies due to primary RyR1 deficiency also exhibit downregulation of the alfa 1 subunit of the DHPR and show disruption of the spatial organization of the EC coupling machinery. We created a cellular RyR1 knockdown model using immortalized human myoblasts transfected with RyR1 siRNA and confirm that knocking down RyR1 concomitantly downregulates not only the DHPR but also the expression of other proteins involved in EC coupling. Unexpectedly, this was paralleled by the upregulation of inositol‐1,4,5‐triphosphate receptors; functionally however, upregulation of the latter Ca²⁺ channels did not compensate for the lack of RyR1‐mediated Ca²⁺ release. These results indicate that in some patients, RyR1 deficiency concomitantly alters the expression pattern of several proteins involved in calcium homeostasis and that this may influence the manifestation of these diseases.