Exposure to heavy metals, antioxidant status, and the interaction of single nucleotide polymorphisms in the genes CAT rs7943316, GSTP1 rs1695, as well as GSTM1 and GSTT1 genes, among workers in occupational settings.

Individuals working in diverse fields are consistently exposed to work-related pollutants that can impact their overall health. The current study investigated the presence of pollutants in seven different occupational groups and their impact on human health. Biochemical and genetic approaches were employed. Heavy metals were determined by ICP-MS technique. Oxidative stress biochemical markers and molecular analysis of the glutathione transferases gene SNPs (GSTT1, GSTM1, GSTP1), catalase (CAT, rs7943316), and superoxide dismutase (SOD, rs17880487) was carried out. The results revealed a significantly higher quantity of Cd among five occupational groups. Catalase, malonaldehyde, and glutathione was significantly dysregulated. Molecular analysis of the gene SNPs suggests a probable relationship between the antioxidants and the phenotypic expression of the CAT, GSTP1, GSTT1, and GSTM1 SNPs. It is concluded that chronic exposure to occupational contaminants like Cd affects human health through oxidative stress in association with some of their gene SNPs.

Determination of cholesterol and triglycerides in serum lipoproteins using flow field-flow fractionation coupled to gas chromatography-mass spectrometry.

Asymmetric flow field flow fractionation (AsFlFFF) was combined with pyrolysis-gas chromatography mass spectrometry for a sized based fractionation and a detailed compositional study of the triglycerides and cholesterol associated with the various lipoprotein subclasses present in human serum. Serum samples were injected in the AsFlFFF instrument and fractionated with a time-delayed exponential decay cross flow program. The fractions collected after AsFlFFF elution were injected into a programmable temperature vaporizer (PTV) GC-injector, containing a fritted liner. A temperature and split-flow program for the PTV injector was optimized for the thermally assisted hydrolysis and methylation of the compounds of interest. The resulting fatty acid and cholesterol methyl esters were separated by GC and characteristic fragment ions were detected by MS. The system was optimized and calibrated with triglyceride and cholesterol standards for quantitative analysis. The possible interference by phospholipids with the quantitative results was investigated and found to be of minor importance. The concentrations and lipoprotein profiles of triglycerides and cholesterol were determined in a pooled serum sample of healthy volunteers and a serum sample of a sepsis patient. The results obtained with the GC-MS approach were compared with those of a previously developed method based on AsFlFFF with a dual enzymatic reaction detection system. A good agreement of the profiles was found, for cholesterol as well as for the triglycerides, even when the GC-MS method quantifies the fatty acids while with the enzymatic reaction method the glycerol concentrations are determined. Total cholesterol and triglyceride concentration values for the serum samples showed good agreement with the results of the standard enzymatic method as used in practice in the university hospital.

Application of flow field-flow fractionation for the characterization of macromolecules of biological interest: a review.

An overview is given of the recent literature on (bio) analytical applications of flow field-flow fractionation (FlFFF). FlFFF is a liquid-phase separation technique that can separate macromolecules and particles according to size. The technique is increasingly used on a routine basis in a variety of application fields. In food analysis, FlFFF is applied to determine the molecular size distribution of starches and modified celluloses, or to study protein aggregation during food processing. In industrial analysis, it is applied for the characterization of polysaccharides that are used as thickeners and dispersing agents. In pharmaceutical and biomedical laboratories, FlFFF is used to monitor the refolding of recombinant proteins, to detect aggregates of antibodies, or to determine the size distribution of drug carrier particles. In environmental studies, FlFFF is used to characterize natural colloids in water streams, and especially to study trace metal distributions over colloidal particles. In this review, first a short discussion of the state of the art in instrumentation is given. Developments in the coupling of FlFFF to various detection modes are then highlighted. Finally, application studies are discussed and ordered according to the type of (bio) macromolecules or bioparticles that are fractionated.

Does the added benefit of ondansetron over dexamethasone, to control post-operative nausea and vomiting, justify the added cost in patients undergoing tonsillectomy and adenotonsillectomy?

OBJECTIVE: To investigate comparative effectiveness of ondansteron and dexamethasone in prophylaxis of PONV in tonsillectomy and adenotonsillectomy patients. METHODS: The study was conducted at Shifa International Hospital Islamabad from 1st January to 30th June 2009, on 60 patients undergoing tonsillectomy or adenotonsillectomy, with their consent. After consecutive alternate sampling, patients were divided into two groups containing 30 patients each. Ondansteron was given in one group, and Dexamethasone in the other group, as anti emetic, at the time of induction. Episodes of PONV were recorded at three specified intervals, i.e., immediate postoperative, 6 hours after surgery and 12 hours after surgery. Data was entered on a pre-designed performa. The data was analyzed in SPSS Version 13.0. RESULTS: Ondansteron Group had a mean age of 12.7 +/- 9.54 years (5-36 years). There were 22 (73.3%) males and 8 (26.7%) females. Dexamethasone Group had a mean age of 14.8 +/- 8.4 years (5-35 years) of whom 18 (60.0%) were males and 12 (40.0%) were females. Overall 6 patients who received ondansetron had PONV compared to 7 patients in the dexamethasone group. This difference was statistically insignificant (p > 0.05). CONCLUSION: Dexamethasone was equally effective in controlling PONV in tonsillectomy and adenotonsillectomy patients. The improved benefit of using ondansetron over dexamethasone, on a regular basis, does not justify the added cost.

The predictors of difficult tracheal intubations in patients undergoing thyroid surgery for euthyroid goitre.

OBJECTIVE: To evaluate the influence of goitre on anatomic features and the correlation of these changes with difficulty in intubation. METHODS: A questionnaire was employed to assess 139 patients scheduled for elective surgery of euthyroid goitre to predict the potential of difficult intubation. These measurements were later correlated with the patients who eventually had difficult intubations. Neck circumference, mouth width, lip test, sternomental distance, thymomental distance, Mallampati score and laryngeal palpation were evaluated. RESULTS: All predictors were found to be significant as single predictors but on logistic regression analysis it was found that the circumference of the neck alone, was the independent predictor for difficult intubation. CONCLUSION: Neck thickness in patients with goitre is a significant predictor of difficult intubation and should be used in preoperative assessment to anticipate difficult intubations.

Fractionation of human serum lipoproteins and simultaneous enzymatic determination of cholesterol and triglycerides.

A method based on Asymmetric Flow Field-Flow Fractionation (AF4) was developed to separate different types of lipoproteins from human serum. The emphasis in the method optimization was on the possibilities to characterize the largest lipoprotein fractions (LDL and VLDL), which is usually not possible with the size-exclusion chromatography methods applied in routine analysis. Different channel geometries and flow programs were tested and compared. The use of a short fractionation channel was shown to give less sample dilution at the same fractionation power compared to a conventional, long channel. Different size selectivities were obtained with an exponential decay and a linear cross flow program. The ratio of the UV absorption signal to the light scattering signal was used to validate the relation between retention time and size of the fractionated particles. An experimental setup was developed for the simultaneous determination of the cholesterol and triglycerides distribution over the lipoprotein fractions, based on enzymatic reactions followed by UV detection at 500 nm. Coiled and knitted PTFE tubing reactors were compared. An improved peak sharpness and sensitivity were observed with the knitted tubing reactor. After optimization of the experimental conditions a satisfactory linearity and precision (2-3% rsd for cholesterol and 5-6% rsd for triglycerides) were obtained. Finally, serum samples, a pooled sample from healthy volunteers and samples of sepsis patients, were analyzed with the method developed. Lipoprotein fractionation and cholesterol and triglyceride distributions could be correlated with the clinical background of the samples.

Association between oestrogen receptor alpha gene polymorphism and mortality in female end-stage renal disease patients.

BACKGROUND: In the general population, genetic variations in the oestrogen receptor alpha (ERalpha) gene may influence lipid abnormalities, cardiovascular disease (CVD), and mortality, but this has not previously been studied in end-stage renal disease (ESRD) patients. METHODS: A total of 227 ESRD (141 men and 86 women) patients starting renal replacement therapy (RRT) were genotyped for three ERalpha gene polymorphisms (Ser10Ser, PvuII and XbaI) and the associations between these polymorphisms and clinical and laboratory parameters and survival were analysed. Patients were followed for a median period of 55 months (range 1-126 months). RESULTS: The PvuII and XbaI polymorphisms were not associated with any of the clinical parameters. The ERalpha Ser10Ser CC genotype was present in 24 (28%) of the female and in 37 (26%) of the male patients. When comparing the CC genotype with the CT and TT genotypes, there were significant differences in lipid levels and inflammatory marker levels, especially in female patients. In female patients, the CC genotype was associated with lower prevalence of protein energy wasting (PEW) (17.4% vs 43.1%; P=0.03), lower median serum triglyceride (1.7 vs 2.1 mmol/l; P=0.001), higher median serum albumin (34.0 vs 32.5 g/l; P=0.03) and lower median high sensitivity-CRP (hsCRP) (2.2 vs 5.5 mg/l; P=0.03) levels compared with the CT plus TT genotypes. In male patients only HDL-cholesterol and ApoA levels were associated with this polymorphism. Whereas this polymorphism did not influence survival in males, the mortality was lower in female patients with the CC genotype (Kaplan-Meier; Log-rank 2.2, P=0.02). Moreover, female patients with the CT plus TT genotypes had a borderline significant increased relative risk (Cox hazard model; 6.6, 95% CI: 0.87-49.9 P=0.06) of death as compared with those with the CC genotype, even after adjustment for age and prevalence of CVD. CONCLUSIONS: Female, but not male ESRD patients with the ERalpha Ser10Ser CC genotype had lower prevalence of PEW, lower serum triglyceride, higher serum albumin and lower hsCRP levels. As this genotype was associated with a significantly decreased risk of all-cause death during the initial years of RRT, its protective properties need further study.