Effect of knowledge of informal poultry drug prescribers on their attitude and practice toward antimicrobial use, residues, and resistance in Bangladesh

Background and Aim

Informal prescribers (IPs) significantly contribute to the development of antimicrobial resistance and in disseminating pathogens from poultry to humans and other animals through the food chain, posing a serious global health threat. Therefore, this study aimed to assess whether the knowledge of IPs has an impact on their attitude and practice toward antimicrobial use, antibiotic residues, and antimicrobial resistance.

Materials and Methods

In this cross-sectional study, we conducted a pre-tested and questionnaire-based survey to investigate the knowledge, attitude, and practice of IPs in selected parts of the Mymensingh division, Bangladesh. Then, we used the linear regression model test with R-squared (R2) to measure the association between the study variables.

Results

Our investigation revealed that 70% of the IPs knew about antibiotics and 75% had good knowledge about antibiotic resistance, whereas only 50% were aware of withdrawal periods. Informal prescribers also displayed good attitudes toward the use and sale of antibiotics with withdrawal periods and completion of medication (50%). Analysis of their practice on the sale and prescription of antibiotics showed that 70% and 30% of IPs use antibiotics against bacterial infections and other conditions, respectively. Most of them do not consult a veterinarian before selling or prescribing antibiotics, although 80% claim to do so. This is because 75% of IPs gave other options regarding their consultations. However, 95% of IPs uses antibiotics only for therapeutic purposes. Furthermore, only 10% sell antibiotics based on a veterinarian's recommendation. Approximately 45% of IPs use single antibiotics at a time, while the rest use multiple antibiotics, individually or combined. Approximately 15% use antibiotics monthly, while 85% use them whenever the need arises. The knowledge and attitude of IPs are significantly affected by their age (p ≤ 0.025). The district of domicile also impacted their knowledge. Surprisingly, IPs from Jamalpur had significantly better knowledge compared to those from Mymensingh and Sherpur (p ≤ 0.01). The attitude of IPs from Jamalpur and Netrokona also differed significantly (p ≤ 0.001) from that of Mymensingh and Sherpur. The knowledge of IPs influenced their attitude up to 80.5% (r2 = 0.628) and their practice up to 75.4% (r2 = 0.545).

Conclusion

The knowledge of IPs greatly influenced their attitude and practice, while sociodemographics also influenced their knowledge and attitude toward antimicrobial use, antibiotic residues, and antimicrobial resistance.

Novel Ta/chitosan-doped CuO nanorods for catalytic purification of industrial wastewater and antimicrobial applications

Novel tantalum (Ta) and chitosan (CS)-doped CuO nanorods (NRs) were synthesized using a single step co-precipitation route. Different concentrations (2 and 4%) of Ta were used in fixed amounts of CS and CuO to examine their catalytic activity and antimicrobial potential. For critical analysis, synthesized NRs were systematically examined using XRD, FTIR HRTEM, EDS, UV-Vis and PL spectroscopy. The XRD technique revealed the monoclinic structure of CuO while an increase in its crystallite size (from 15.5 to 18.5 nm) was observed upon doping. FTIR spectra were examined to study the functional groups of CuO where peaks at 514 cm-1 and 603 cm-1 confirmed the formation of CuO NRs. PL spectra depicted the charge transfer efficiency of the synthesized samples. The presence of dopants (Ta and CS) and constituent elements (Cu, O) was detected using EDS spectra. Additionally, the pH based catalytic performance of fabricated NRs revealed 99.7% dye degradation of toxic methylene blue (MB) dye in neutral media, 99.4% in basic media and 99.5% in acidic media along with promising antibacterial activities for Gram negative/positive bacteria, respectively upon doping of Ta (4%) into CS/CuO. The adsorption energies of CuO co-doped with CS/Ta led to the creation of stable structures that were investigated theoretically using density functional theory.

Optimized biotransformation of acid-treated water melon peel hydrolyzate into ethanol

Today, global focus of research is to explore the solution of energy crisis and environmental pollution. Like other agricultural countries, bulk quantities of watermelon peels (WMP) are disposed-off in environment as waste in Pakistan and appropriate management of this waste is the need of hour to save environment from pollution. The work emphasizes the role of ethanologenic yeasts to utilize significant sugars present in WMP for low-cost bioethanol fermentation. Dilute hydrochloric acid hydrolysis of WMP was carried out on optimized conditions employing RSM (response surface methodology) following central composite design (CCD). This experimental design is based on optimization of ethanologenesis involving some key independent parameters such as WMP hydrolysate and synthetic media ratio (X1), incubation temperature (X2) and incubation temperature (X3) for maximal ethanol yield exploiting standard (Saccharomyces cerevisiae K7) as well as experimental (Metchnikowia cibodasensisY34) yeasts. The results revealed that maximal ethanol yields obtained from S. cerevisiae K7 was 0.36±0.02 g/g of reducing sugars whereas M. cibodasensisY34, yielded 0.40±0.01 g ethanol/g of reducing sugars. The yeast isolate M. cibodasensisY34 appeared as promising ethanologen and embodies prospective potential for fermentative valorization of WMP-to-bioethanol.

Antiadhesion and antibiofilm potential of Fagonia indica from Cholistan desert against clinical multidrug resistant bacteria

High resistance to antimicrobials is associated with biofilm formation responsible for infectious microbes to withstand severe conditions. Therefore, new alternatives are necessary as biofilm inhibitors to control infections. In this study, the antimicrobial and antibiofilm activities of Fagonia indica extracts were evaluated against MDR clinical isolates. The extract exhibited its antibiofilm effect by altering adherence and disintegration of bacterial cell wall. Fagonia indica has antibacterial effect as minimum inhibitory concentration (MIC) values ranging from 125 to 500 µg mL-1 and minimum bactericidal concentration (MBC) value was 500-3000 µg mL-1 against multidrug resistant (MDR) clinical isolates. The extract exhibited its antibiofilm effect by altering adherence and disintegration of bacterial cell wall. Fagonia indica had antibacterial effect as minimum inhibitory concentration (MIC) values ranging from 125 to 500 µg mL-1 and minimum bactericidal concentration (MBC) value was 500-3000 µg mL-1 against MDR isolates. The maximum inhibitory effects of Fagonia indica chloroform extract on biofilm formation was observed on Staphylococcus aureus (71.84%) followed by Klebsiella pneumoniae (70.83%) after 48 hrs showing that inhibition is also time dependent. Our results about bacterial cell protein leakage indicated that MDR isolates treated with chloroform extract of Fagonia indica showed maximum protein leakage of K. pneumoniae (59.14 µg mL-1) followed by S. aureus (56.7 µg mL-1). Cell attachment assays indicated that chloroform extract resulted in a 43.5-53.5% inhibition of cell adherence to a polystyrene surface. Our results revealed that extracts of Fagonia indica significantly inhibited biofilm formation among MDR clinical isolates, therefore, could be applied as antimicrobial agents and cost effective biofilm inhibitor against these MDR isolates.

Novel Ag/cellulose-doped CeO2 quantum dots for efficient dye degradation and bactericidal activity with molecular docking study

In the present study, the novel Ag/cellulose nanocrystal (CNC)-doped CeO₂ quantum dots (QDs) with highly efficient catalytic performance were synthesized using one pot co-precipitation technique, which were then applied in the degradation of methylene blue and ciprofloxacin (MBCF) in wastewater. Catalytic activity against MBCF dye was significantly reduced (99.3%) for (4%) Ag dopant concentration in acidic medium. For Ag/CNC-doped CeO₂ vast inhibition domain of G-ve was significantly confirmed as (5.25-11.70 mm) and (7.15-13.60 mm), while medium- to high-concentration of CNC levels were calculated for G + ve (0.95 nm, 1.65 mm), respectively. Overall, (4%) Ag/CNC-doped CeO₂ revealed significant antimicrobial activity against G-ve relative to G + ve at both concentrations, respectively. Furthermore, in silico molecular docking studies were performed against selected enzyme targets dihydrofolate reductase (DHFR), dihydropteroate synthase (DHPS), and DNA gyrase belonging to folate and nucleic acid biosynthetic pathway, respectively to rationalize possible mechanism behind bactericidal potential of CNC-CeO₂ and Ag/CNC-CeO₂.

Graphene Oxide-Doped MgO Nanostructures for Highly Efficient Dye Degradation and Bactericidal Action

Various concentrations (0.01, 0.03 and 0.05 wt ratios) of graphene oxide (GO) nanosheets were doped into magnesium oxide (MgO) nanostructures using chemical precipitation technique. The objective was to study the effect of GO dopant concentrations on the catalytic and antibacterial behavior of fixed amount of MgO. XRD technique revealed cubic phase of MgO, while its crystalline nature was confirmed through SAED profiles. Functional groups presence and Mg-O (443 cm-1) in fingerprint region was evident with FTIR spectroscopy. Optical properties were recorded via UV-visible spectroscopy with redshift pointing to a decrease in band gap energy from 5.0 to 4.8 eV upon doping. Electron-hole recombination behavior was examined through photoluminescence (PL) spectroscopy. Raman spectra exhibited D band (1338 cm-1) and G band (1598 cm-1) evident to GO doping. Formation of nanostructure with cubic and hexagon morphology was confirmed with TEM, whereas interlayer average d-spacing of 0.23 nm was assessed using HR-TEM. Dopants existence and evaluation of elemental constitution Mg, O were corroborated using EDS technique. Catalytic activity against methyl blue ciprofloxacin (MBCF) was significantly reduced (45%) for higher GO dopant concentration (0.05), whereas bactericidal activity of MgO against E. coli was improved significantly (4.85 mm inhibition zone) upon doping with higher concentration (0.05) of GO, owing to the formation of nanorods.

AB0176 RISK OF ANTI-CITRULLINATED PEPTIDE ANTIBODIES AND RHEUMATOID FACTOR IN MALE SMOKERS: DATA FROM KUWAIT REGISTRY FOR RHEUMATIC DISEASES (KRRD)

Background:

Smoking has been proposed to be associated with the development of anti-citrullinated peptide antibodies (ACPA) in rheumatoid arthritis (RA) patients.

Objectives:

To study the relationship between smoking and ACPA as well as smoking and RF in patients with RA in Kuwait Registry for Rheumatic Diseases (KRRD).

Methods:

Data on RA patients were extracted from KRRD from four major hospitals from February 2013 through December 2019. As females rarely smoke in Kuwait with a smoking prevalence of 3% in female RA patients in KRRD, females were excluded from the study population to reach the minimum statistical percentage needed to perform chi square test and assess the association between smoking and other variables. Statistical tests were applied where appropriate. Logistic regression was conducted to adjust for possible confounders including age, disease duration, comorbidities, family history of a rheumatic disease, ANA, treatment agents and disease activity and quality of life assessment tools.

Results:

A total of 863 RA male patients were studied with a mean age of 53.9±12.5 years and a mean disease duration 7.3±5.5 years. 652 (75.6%) had positive RF and 624 (72.3%) had positive ACPA. 431 (50%) had at least one comorbidity. 640 (74.2%) were on conventional disease modifying agents (cDMARD’s) and 223 (25.8%) were on biologic therapy. 183 (21.2%) were smokers. After adjustment of other factors, logistic regression showed that smokers were significantly different than non-smokers in terms of a positive ACPA (β=-1.051,p<0.001, odds=4.019) and a positive RF (β=-0.804,p=0.019, odds=2.517).

Conclusion:

Smokers have a higher risk of expressing a positive RF and a positive ACPA in a male population. Smoking should be considered as a possible risk factor for RA and efforts should be done to educate the population to cease smoking to possibly lower that risk.

References:

[1]Benowitz, N.L., 2009. Pharmacology of nicotine: addiction, smoking-induced disease, and therapeutics. Annual review of pharmacology and toxicology, 49, pp.57-71.

[2]Firestein, G.S., 2003. Evolving concepts of rheumatoid arthritis. Nature, 423(6937), p.356.

[3]Heliövaara, M., Aho, K., Aromaa, A., Knekt, P. and Reunanen, A., 1993. Smoking and risk of rheumatoid arthritis. The Journal of rheumatology, 20(11), pp.1830-1835.

[4]Hoy, K. W., 2009. Quantitative Research in Education: A Primer. SAGE. pp. 69-86.

[5]Kerlan-Candon, S., Combe, B., Vincent, R., Clot, J., Pinet, V. and Eliaou, J.F., 2001. HLA-DRB1 gene transcripts in rheumatoid arthritis. Clinical & Experimental Immunology, 124(1), pp.142-149.

[6]Kuada, J., 2012. Research Methodology: A Project Guide for University Students. Samfundslitteratur. pp. 45-56.

[7]Kumar, R., 2010. Research Methodology: A Step-by-Step Guide for Beginners. SAGE. pp. 148-159.

[8]Masdottir, B., Jonsson, T., Manfreðsdóttir, V., Víkingsson, A., Brekkan, Á. and Valdimarsson, H., 2000. Smoking, rheumatoid factor isotypes and severity of rheumatoid arthritis. Rheumatology, 39(11), pp.1202-1205.

[9]Neuman, W., 2009. Understanding research. Boston: Pearson. pp. 230- 255.

Disclosure of Interests:

None declared

THU0556 MISSING DATA AND MULTIPLE IMPUTATION IN RHEUMATOID ARTHRITIS REGISTRIES USING SEQUENTIAL RANDOM FOREST METHOD

Background:

Missing data in clinical epidemiological researches violate the intention to treat principle,

reduce statistical power and can induce bias if they are related to patient’s response to treatment. In multiple imputation (MI), covariates are included in the imputation equation to predict the values of missing data.

Objectives:

To find the best approach to estimate and impute the missing values in Kuwait Registry for Rheumatic Diseases (KRRD) patients data.

Methods:

A number of methods were implemented for dealing with missing data. These includedMultivariate imputation by chained equations(MICE),K-Nearest Neighbors(KNN),Bayesian Principal Component Analysis(BPCA),EM with Bootstrapping(Amelia II),Sequential Random Forest(MissForest) and mean imputation. Choosing the best imputation method was

judged by the minimum scores ofRoot Mean Square Error(RMSE),Mean Absolute Error(MAE) and

Kolmogorov–Smirnov D test statistic(KS) between the imputed datapoints and the original datapoints that were subsequently sat to missing.

Results:

A total of 1,685 rheumatoid arthritis (RA) patients and 10,613 hospital visits were included in the registry. Among them, we found a number of variables that had missing values exceeding 5% of the total values. These included duration of RA (13.0%), smoking history (26.3%), rheumatoid factor (7.93%), anti-citrullinated peptide antibodies (20.5%), anti-nuclear antibodies (20.4%), sicca symptoms (19.2%), family history of a rheumatic disease (28.5%), steroid therapy (5.94%), ESR (5.16%), CRP (22.9%) and SDAI (38.0%), The results showed that among the methods used, MissForest gave the highest level of accuracy to estimate the missing values. It had the least imputation errors for both continuous and categorical variables at each frequency of missingness and it had the smallest prediction differences when the models used imputed laboratory values. In both data sets, MICE had the second least imputation errors and prediction differences, followed by KNN and mean imputation.

Conclusion:

MissForest is a highly accurate method of imputation for missing data in KRRD and outperforms other common imputation techniques in terms of imputation error and maintenance of predictive ability with imputed values in clinical predictive models. This approach can be used in registries to improve the accuracy of data, including the ones for rheumatoid arthritis patients.

References:

[1]Junninen, H.; Niska, H.; Tuppurainen, K.; Ruuskanen, J.; Kolehmainen, M. Methods for imputation of

missing values in air quality data sets.Atmospheric Environment2004,38, 2895–2907.

[2]Norazian, M.N.; Shukri, Y.A.; Azam, R.N.; Al Bakri, A.M.M. Estimation of missing values in air pollution

data using single imputation techniques.ScienceAsia2008,34, 341–345.

[3]Plaia, A.; Bondi, A. Single imputation method of missing values in environmental pollution data sets.

Atmospheric Environment2006,40, 7316–7330.

[4]Kabir, G.; Tesfamariam, S.; Hemsing, J.; Sadiq, R. Handling incomplete and missing data in water network

database using imputation methods.Sustainable and Resilient Infrastructure2019, pp. 1–13.

[5]Di Zio, M.; Guarnera, U.; Luzi, O. Imputation through finite Gaussian mixture models.Computational

Statistics & Data Analysis2007,51, 5305–5316.

Disclosure of Interests:

None declared

P2837Day-case complex left atrial ablation is safe and cost-effective: experience from a UK tertiary centre

Background

Day-case standard catheter ablation is becoming routine. However, patients having complex left atrial ablation for atrial fibrillation (AF) or left atrial tachycardia (LAT) often stay overnight. We have been performing day-case complex left atrial ablation since 2015.

Purpose

To evaluate the safety, efficacy and cost-effectiveness of day-case complex left atrial ablation compared with those who stayed overnight.

Methods

A retrospective analysis of all consecutive complex left atrial ablations performed in a UK tertiary cardiac centre between 2010–2018. Data were collected on baseline parameters, procedure details including mapping technique, ablation strategy, immediate efficacy, and acute complications.

Results

A total of 830 complex left atrial catheter ablations were performed; mean age±SD=60±12 years, 63% male. The majority were AF ablation (n=804, 96.9%), with the rest being LAT/left-atrial flutter. Of the AF cases, 545 were paroxysmal (≤7 days), 212 persistent (>7 days) and 47 long-standing (>1yr); 98% of cases were elective. Pulmonary vein isolation was performed in all; additional LA lines were done in 163, CTI ablation in 129 and CFAEs in 33. 3D-mapping (Carto/Precision)=44.7% (with contact sensing=38.0%), PVAC=18.7%, PVI cryo-balloon=36.6%. Of the cohort 331 (39.9%) were done as day-case. Acute success= 94.9%, acute complications=4.58% (femoral site complications, n=12; pericardial effusion, n=19 (9 needing drain); stroke/cerebral embolus, n=3; phrenic nerve palsy, n=5; first degree heart block, n=1). Comparison of day-case vs non day-case revealed no significant difference in number of complications (Table 1). An overnight stay at out hospital costs £350. During the period of study our institution saved £115.850 (∼140,000 euros).

Day-case vs non day-case ablation Parameters Day-case (n=331) Non day-case (n=499) p-value Mean age ± SD (years) 61.2±11.6 59.1±11.9 0.009 Males (n, %) 205 (61.9%) 321 (64.3%) 0.484 Normal heart (n, %) 243 (73.4%) 383 (76.8%) 0.276 Paroxysmal AF (n, %) 218 (65.9%) 327 (65.5%) 0.928 Fluoroscopy time (mins) 23.8±13.9 27.0±14.5 0.001 Procedure time (mins) 150±89.6 163±68.2 0.025 % with 3D-mapping 30.8% 56.9% <0.001 Acute complications (n, %) 12 (3.63%) 26 (5.21%) 0.285

Conclusions

Day-case complex left atrial cardiac ablation is safe and effective. It is associated with good clinical outcomes and leads to significant cost savings as an overnight stay is not needed.

P5975Diminished LV systolic velocity on tissue Doppler imaging is linked to an amplified risk of lethal arrhythmias independently of LV ejection fraction

Background

Life threatening arrhythmias (LTA) can trigger sudden cardiac death, or provoke implantable cardioverter defibrillator (ICD) discharges that escalate morbidity and mortality. Longitudinal myofibrils predominate in the subendocardium which is uniquely sensitive to arrhythmogenic triggers.

Objectives

To test the hypothesis that mitral annular systolic velocity (S'), a tissue Doppler index of LV long-axis systolic function, might predict lethal arrhythmias irrespective of LVEF.

Methods

We analysed data from diverse ICD and cardiac resynchronization therapy defibrillator (CRT-D) patients at 2 London centres. Channelopathies were excluded. S' was averaged from medial and lateral mitral annuli velocities. Primary outcome was time to sustained ventricular tachycardia (VT) or fibrillation (VF) needing device therapy.

Results

In 302 patients (mean age 68 years, LVEF 32%, 77% male, 52% ischemic, 35% primary prevention, and 53% CRT-D), median S' was 5.1 (IQR: 4.0–6.2) cm/s and lower in CRT-D than ICD subjects. After a median follow-up of 15 months, 56 (19%) subjects had LTA and those who did had a lower S' than those who did not (4.6±1.4 cm/s vs. 5.4±1.7 cm/s, P=0.003-Fig A). Each 1cm/s lower S' correlated to a 43% increased risk of LTA (HR: 0.70, 95% CI: 0.57–0.87, P=0.001) independently of age, gender, β-blocker use, centre, ICD use and LVEF. Adding S' to the baseline model improved net reclassification (P=0.02) implying incremental utility (Fig B). An S' ≤5.6cm/s was the best cut-off, conferring a 2.4-fold higher LTA risk than an S'>5.6 cm/s (95% CI: 1.17–4.37, P=0.02–Fig C).

Conclusion

A lower S' forecasts an enhanced probability of LTA in cardiac device recipients irrespective of LVEF, and could be used to titrate medical, device and ablative therapies to mitigate future arrhythmic risk.

P6561Diagnostic yield of implantable loop recorders: a comparison of arrhythmia nurse specialists versus clinicians

Background

Implantable loop recorders (ILR) are recommended in guidelines to determine symptom-rhythm correlation. Arrhythmia Nurse Specialists (ANS) play a critical role in the assessment of such patients. Their effectiveness at risk stratification for ILR implantation is unknown. The ESC 2018 Syncope guidelines recommend more research in this field.

Aim

To evaluate the diagnostic yield of consecutive ILR implants at a tertiary centre over a 2year period and compare ANS versus Clinicians.

Methods

A retrospective study of all patients undergoing ILR implant between April 2016 and April 2018. Data collected included baseline patient demographics, referral source and management changes made by ILR findings.

Results

305 patients had an ILR; median age was 71yrs (interquartile range 52–81), 55% male. Median follow-up time was 15months. Referrals were from general cardiology (GC) = 98 (32%), electrophysiology (EP) = 105 (34%), and ANS-led syncope clinic = 102 (34%). Indications for ILR implant were syncope = 203 (65.9%), palpitation = 21 (6.9%), pre-syncope = 16 (5.2%), cryptogenic stroke = 35 (11.5%) and others 7 (8.9%) (falls, channelopathies). Of the entire cohort, 102 (34.0%) experienced arrhythmias recorded on the ILR that resulted in a change of management. This included: pacemaker implant = 49 (16.1%), complex-device implant = 7 (2.3%), AF=28 (9.2%), SVT=14 (4.6%), VT=1 (0.3%). Of those with a syncope indication (n=203), findings on ILR altered management in 73patients (36.0%) over a median follow-up of 18months; a pacing indication in this syncope group was present in 44 (21.9%) patients (median time to diagnosis: 2.7 months) with 24 receiving a pacemaker indication within 3 months of ILR insertion. ANS had a higher pacemaker implant rate. Overall, an ILR resulted in a diagnostic yield of 34.1% (n=104). Specialist nurse referral resulted in an overall greater trend towards change of management in 38.2% of patients compared with GC (32.7%) and EP (31.0%) (p=0.593 nurse vs. consultant).

Conclusion

The overall diagnostic yield of ILR insertion was 34% in our study. ANS had a trend towards a greater diagnostic yield compared with clinicians, and significantly more pacemaker indications. Our data suggests that ANS patient selection for ILR insertion are at least comparable to clinicians.

Abnormalities of age-related T cell senescence in Parkinson's disease

BACKGROUND

A wealth of evidence implicates both central and peripheral immune changes as contributing to the pathogenesis of Parkinson's disease (PD). It is critical to better understand this aspect of PD given that it is a tractable target for disease-modifying therapy. Age-related changes are known to occur in the immune system (immunosenescence) and might be of particular relevance in PD given that its prevalence rises with increasing age. We therefore sought to investigate this with respect to T cell replicative senescence, a key immune component of human ageing.

METHODS

Peripheral blood mononuclear cells were extracted from blood samples from 41 patients with mild PD (Hoehn and Yahr stages 1-2, mean (SD) disease duration 4.3 (1.2) years) and 41 age- and gender-matched controls. Immunophenotyping was performed with flow cytometry using markers of T lymphocyte activation and senescence (CD3, CD4, CD8, HLA-DR, CD38, CD28, CCR7, CD45RA, CD57, CD31). Cytomegalovirus (CMV) serology was measured given its proposed relevance in driving T cell senescence.

RESULTS

Markers of replicative senescence in the CD8+ population were strikingly reduced in PD cases versus controls (reduced CD57 expression (p = 0.005), reduced percentage of 'late differentiated' CD57_loCD28_hi cells (p = 0.007) and 'TEMRA' cells (p = 0.042)), whilst expression of activation markers (CD28) was increased (p = 0.005). This was not driven by differences in CMV seropositivity. No significant changes were observed in the CD4 population.

CONCLUSIONS

This study demonstrates for the first time that the peripheral immune profile in PD is distinctly atypical for an older population, with a lack of the CD8+ T cell replicative senescence which characterises normal ageing. This suggests that 'abnormal' immune ageing may contribute to the development of PD, and markers of T cell senescence warrant further investigation as potential biomarkers in this condition.

Is foliar spray of proline sufficient for mitigation of salt stress in Brassica juncea cultivars?

The effects of foliar application of proline (20 mM) on growth, physio-biochemical, and yield parameters were assessed in two Brassica juncea (L.) Czern & Coss cultivars, namely, Varuna and RH-30, at different levels (2.8, 4.2, or 5.6 dsm(-1)) of NaCl in soil. At 29 days after sowing (DAS), plants were sprayed with either 20 mM proline or water in the presence or absence of NaCl stress. The NaCl negatively affected parameters related to growth, photosynthesis, and yield in both varieties but more in RH-30 than in Varuna. Exogenous application of proline counteracted the effects of salt stress in Varuna only, by increasing the antioxidative capacity of the plants. Moreover, proline was not effective in alleviating the detrimental effects of higher salt concentrations on the studied parameters. Proline application to unstressed plants increased growth, photosynthesis, and yield parameters in both varieties; however, the effects were more prominent in Varuna than in RH-30.

Automated retinal vessel recognition and measurements on large datasets

The characteristics of the retinal vascular network have been prospectively associated with many systemic and vascular diseases. QUARTZ is a fully automated software that has been developed to localize and quantify the morphological characteristics of blood vessels in retinal images for use in epidemiological studies. This software was used to analyse a dataset containing 16,000 retinal images from the EPIC-Norfolk cohort study. The objective of this paper is to both assess the suitability of this dataset for computational analysis and to further evaluate the QUARTZ software.

Cross-sectional associations between different measures of obesity and muscle strength in men and women in a British cohort study

OBJECTIVES

The relationship between obesity and grip strength, a key indicator of sarcopenia, has been inconsistently reported. We aimed to examine associations between grip strength and both body mass index (BMI), a clinical indicator of total adiposity, and waist circumference (WC), an indicator of central adiposity.

DESIGN

Cross-sectional study.

SETTING AND PARTICIPANTS

Data collected from 8,441 men and women, aged 48-92 years old, who attended the third health examination of the European Prospective Investigation into Cancer-Norfolk study was used.

MEASUREMENTS

Maximum grip strength (Smedley dynamometer), BMI (weight/height2) and WC (measured at the natural waist) were ascertained at a research clinic. The associations between grip strength and adiposity measures were explored using linear regression with adjustment for age, height, social class, physical activity, prevalent disease, smoking status and alcohol intake.

RESULTS

Men and women were examined separately and those in the upper quartile of BMI were 2.70kg (95%CI 2.07, 3.33) and 1.46kg (95%CI 1.05, 1.86) stronger respectively than those in the bottom quartile (P trends <0.001). Grip strength also increased weakly with increasing WC. However, including both BMI and WC in the same regression model revealed an inverse association between grip strength and WC, whilst the previously observed association with BMI strengthened. For every 10cm increase in WC, grip strength was 3.56kg (95%CI 3.04, 4.08) lower in men and 1.00kg (95%CI 0.74, 1.24) lower in women.

CONCLUSIONS

Larger overall body mass, indicated by higher BMI, is associated with stronger grip strength but high WC, a clinical indicator of central obesity, is associated with lower grip strength. Abdominal fat is the most metabolically active adipose tissue and this provides a clue to potential mechanisms underlying relationships between fat and skeletal muscle. Additionally, it reinforces the recommendation to measure WC in clinical practice, especially when BMI is below obese ranges.

Diagnostic Efficacy of HbA1c in Diagnosis of Diabetes Mellitus in a Bangladesh Population

American Diabetic Association (ADA) affirms HbA1c with cut off value of 6.5% as a diagnostic criteria of diabetes mellitus. World Health Organization (WHO) also supports but recommended that a value <6.5% does not exclude diabetes which is diagnosed by glucose test. The aim of this study was to evaluate the diagnostic efficacy of HbA1c in terms of sensitivity, specificity, positive and negative predictive value and accuracy in a selected group of Bangladeshi subjects. This cross-sectional study included 761 adult Bangladeshi subjects of both sex attending the outdoor in a tertiary healthcare center during the period of September 2009 to September 2010. Fasting, postprandial (2 hours after glucose load) plasma glucose and HbA1c were measured. Diabetes is defined according to HbA1c and plasma glucose. Sensitivity, specificity, positive and negative predictive value of HbA1c were 90.00% (CI 86.48-92.86%), 76.21% (CI 71.68-80.35%), 78.17% (CI 73.94-82.00%) and 88.96% (CI 85.10-92.10%) respectively. Accuracy was 82.92% with odds ratio (OR) 28.84 (CI 19.10-43.54%); p < 0.001. Though HbA1c revealed remarkable diagnostic efficacy and ease of performance, still it can not over rule the role of plasma glucose in diagnosis of diabetes mellitus. DOI: http://dx.doi.org/10.3329/bmj.v41i1.18785 Bangladesh Medical Journal 2012 Vol. 41 No. 1; 53-54

The association between social stress and global cognitive function in a population-based study: the European Prospective Investigation into Cancer (EPIC)-Norfolk study

BACKGROUND

Stress is thought to exert both positive and negative effects on cognition, but the precise cognitive effects of social stress and individuals' response to stress remain unclear. We aimed to investigate the association between different measures of social stress and cognitive function in a middle- to older-aged population using data from the European Prospective Investigation into Cancer (EPIC)-Norfolk study.

METHOD

Participants completed a comprehensive assessment of lifetime social adversity between 1993 and 1997 and the short form of the Mini Mental State Examination (SF-MMSE), an assessment of global cognitive function, during the third health check between 2004 and 2011 (a median of 10.5 years later). A low MMSE score was defined as a score in the bottom quartile (20-26).

RESULTS

Completed MMSE scores and stress measures were available for 5129 participants aged 48-90 years. Participants who reported that their lives had been more stressful over the previous 10 years were significantly more likely to have low MMSE scores [odds ratio (OR) 1.14, 95% confidence interval (CI) 1.04-1.24 per unit increase in perceived stress], independently of sociodemographic factors, physical and emotional health. The effects were restricted to the highest level of stress and the association was stronger among participants with a lower educational level. Adaptation following life event experiences also seemed to be associated with MMSE scores after adjusting for sociodemographic factors, but the association was attenuated with further adjustment.

CONCLUSIONS

In this generally high-functioning population, individuals' interpretations and responses to stressful events, rather than the events themselves, were associated with cognitive function.

Nickel: an overview of uptake, essentiality and toxicity in plants

Nickel even though recognized as a trace element, its metabolism is very decisive for certain enzyme activities, maintaining proper cellular redox state and various other biochemical, physiological and growth responses. Study of the aspects related with uptake, transport and distributive localization of Ni is very important in various cellular metabolic processes particularly under increased nitrogen metabolism. This review article, in core, encompasses the dual behavior of Ni in plants emphasizing its systemic partitioning, essentiality and ill effects. However, the core mechanism of molecules involved and the successive physiological conditions required starting from the soil absorption, neutralization and toxicity generated is still elusive, and varies among the plants.

Quantitative structure activity relationship and risk analysis of some heavy metal residues in the milk of cattle and goat

Milk of cattle and goat was collected from various localities of Faisalabad, Pakistan. Heavy metal concentration in milk was determined by atomic absorption spectrophotometer. Milk from both of the species was found richly contaminated with cadmium (Cd), chromium (Cr), nickel (Ni), and lead (Pb). Lead concentration in the milk of goat was significantly higher as compared to cattle milk. Quantitative structure activity relationship (QSAR) models were suggested to predict the residues of unknown heavy metals in the milk of cattle and goat using their known physicochemical properties such as molecular weight (MW), melting point (MP), and boiling point (BP) as well as the milk characteristics such as pH, % fat, and specific gravity (SG) of both of these species. The analysis revealed good correlation coefficients ( R2 = 0.759) and ( R2 = 0.876) for cattle and goat QSAR models, respectively. This analysis indicates the need to construct species specific QSAR models for residue prediction. The coefficients for SG for the studied metals were higher in both cattle and goat milk. This suggests that SG is a better determinant for heavy metal residue prediction in the milk of these animals. Risk analysis was conducted based upon the determined heavy metal residues and their provisional tolerable daily intakes. The daily intake of Cd, Cr, and Pb was found to be 1.6, 27, and 116 times higher, respectively, in cattle milk and 1.8, 29, 262 times higher respectively, in goat milk. This intake of heavy metal contaminated milk might pose health hazards to humans in this locality.

Cadmium: toxicity and tolerance in plants

Of all the non-essential heavy metals, cadmium (Cd) is perhaps the metal which has attracted the most attention in soil science and plant nutrition due to its potential toxicity to humans, and also its relative mobility in the soil-plant system. This review summarizes the toxic symptoms of Cd in plants (i.e. growth retardation, alterations of photosynthesis, stomatal movement, enzymatic activities, water relations, interferences with mineral uptake, protein metabolism, membrane functioning, etc.) but also includes the mechanisms of cadmium uptake, translocation and deposition. Moreover, it also throws light on chelation, including identification of Cd ligands present in cytosol and vascular tissue. Cadmium-induced oxidative stress is also considered as one of the most widely studied topics in this review.

24-Epibrassinolide protects against the stress generated by salinity and nickel in Brassica juncea

The plants of Brassica juncea (L) were grown in the presence of NaCl and/or NiCl2 and were sprayed with 1muM of 24-epibrassinolide (EBL) at 15 days after sowing (DAS) and were sampled at 30 DAS. The plants exposed to NaCl and/or NiCl2 exhibited a significant decline in growth, the level of pigments and photosynthetic parameters. However, the follow up treatment with EBL detoxified the stress generated by NaCl and/or NiCl2 and significantly improved the above parameters. The NaCl and/or NiCl2 increased electrolyte leakage and lipid peroxidation, and decreased the membrane stability index (MSI) and relative water content. However, the EBL treatment in absence of the stress improved the MSI and relative water content but could not influence electrolyte leakage and lipid peroxidation. The antioxidative enzymes and the level of proline exhibited a significant increase in response to EBL as well as to NaCl and/or NiCl2 stress.

28-homobrassinolide protects chickpea (Cicer arietinum) from cadmium toxicity by stimulating antioxidants

In the present experiment the seeds of Cicer arietinum (L.) cv. Uday were inoculated with specific Rhizobium grown in sandy loam soil and were allowed to grow for 15 days. At this stage, the seedlings were supplied with 0, 50, 100 or 150 microM of cadmium in the form of cadmium chloride and sprayed with 0.01 microM of 28-homobrassinolide (HBL) at 30-day stage. The data indicated that plant fresh and dry mass, number of nodules, their fresh and dry mass, leghemoglobin content, nitrogen and carbohydrate content in the nodules, leaf chlorophyll content, nitrate reductase and carbonic anhydrase activities decreased proportionately with the increasing concentrations of cadmium but the content of proline and the activities of catalase, peroxidase and superoxide dismutase increased. The ill effect, generated by cadmium, was overcome if the stressed plants were sprayed with HBL.

Selective inhibition of MEK1/2 reveals a differential requirement for ERK1/2 signalling in the regulation of HIF-1 in response to hypoxia and IGF-1

The transcription factor hypoxia-inducible factor 1 (HIF-1) plays a pivotal role in tumour growth and progression, and HIF-1 is regulated through a number of signalling pathways. Here, we investigated the involvement of the mitogen-activated protein kinase (MAPK) signalling pathway in HIF-1 regulation. We found that overexpression of wild-type (WT) extracellular signal regulated protein kinase 1 (ERK1) greatly potentiated HIF-1 activation in hypoxia and HIF-1alpha induced in response to insulin growth-like factor 1 (IGF-1). Conversely, treatment of tumour cells with the MEK1/2 inhibitors PD98059 or U0216, or expression of a dominant-negative form of ERK1 blocked HIF-1 activation in hypoxia without affecting HIF-1alpha induction, localization or binding of HIF-1beta. Interestingly however, the highly selective MEK1/2 inhibitor PD184352 did not inhibit HIF-1 activity or vascular endothelial growth factor (VEGF) induced in response to hypoxia but blocked HIF-1alpha protein and HIF-1 activity induced by IGF-1 stimulation without affecting HIF-1alpha mRNA levels. Finally, we found that ERK5 phosphorylation status was not significantly affected by hypoxia in the presence or absence of PD184352. Taken together, our data suggest that although ERK1/2 signalling is important for HIF-1alpha induction and HIF-1 activity in response to IGF-1, it is dispensable for the induction of HIF-1alpha and activation of HIF-1 in response to hypoxia.

Acute myocardial infarction following sildenafil intake in a nitrate-free patient without previous history of coronary artery disease

OBJECTIVE

To report the occurrence of acute myocardial infarction (MI) associated with the intake of oral sildenafil (Viagra) in a nitrate-free patient without previous history of coronary artery disease.

CASE PRESENTATION AND INTERVENTION

A 50-year-old manual laborer was admitted to the hospital with acute inferoposterior wall MI occurring approximately 30 min after taking oral sildenafil 50 mg. This occurred before any attempted sexual activity. Subsequent angiography showed a 70% stenotic lesion in the midsegment of the dominant circumflex artery. The Naranjo scale indicated that sildenafil was a probable cause of MI.

CONCLUSION

This report shows a rare sildenafil-associated MI in a nitrate-free patient without a previous history of coronary artery disease.

Effect of salicylic acid on growth and enzyme activities of wheat seedlings

grains of wheat (Triticum aestivumL. cv. Raj-3077) were soaked in 0, 10-5, 10-4or 10-3 M aqueous solutions of salicylic acid (SA) for 3, 6 or 9 h. The seedlings raised from grains pre-treated with 10-5 M SA possessed significantly higher leaf number, fresh and dry mass per plant, and nitrate reductase and carbonic anhydrase activities 30 and 40 days after sowing. However, 10-3 M SA reduced all the above-mentioned parameters.