Gel Tubes Research Articles

Impact of Uniform Methods on Interlaboratory Antibody Titration Variability: Antibody Titration and Uniform Methods.

-Substantial variability between different antibody titration methods prompted development and introduction of uniform methods in 2008. -To determine whether uniform methods consistently decrease interlaboratory variation in proficiency testing. -Proficiency testing data for antibody titration between 2009 and 2013 were obtained from the College of American Pathologists. Each laboratory was supplied plasma and red cells to determine anti-A and anti-D antibody titers by their standard method: gel or tube by uniform or other methods at different testing phases (immediate spin and/or room temperature [anti-A], and/or anti-human globulin [AHG: anti-A and anti-D]) with different additives. Interlaboratory variations were compared by analyzing the distribution of titer results by method and phase. -A median of 574 and 1100 responses were reported for anti-A and anti-D antibody titers, respectively, during a 5-year period. The 3 most frequent (median) methods performed for anti-A antibody were uniform tube room temperature (147.5; range, 119-159), uniform tube AHG (143.5; range, 134-150), and other tube AHG (97; range, 82-116); for anti-D antibody, the methods were other tube (451; range, 431-465), uniform tube (404; range, 382-462), and uniform gel (137; range, 121-153). Of the larger reported methods, uniform gel AHG phase for anti-A and anti-D antibodies had the most participants with the same result (mode). For anti-A antibody, 0 of 8 (uniform versus other tube room temperature) and 1 of 8 (uniform versus other tube AHG), and for anti-D antibody, 0 of 8 (uniform versus other tube) and 0 of 8 (uniform versus other gel) proficiency tests showed significant titer variability reduction. -Uniform methods harmonize laboratory techniques but rarely reduce interlaboratory titer variance in comparison with other methods.

Fabrication of Micron-Scale Cylindrical Tubes by Two-Photon Polymerization

Hollow cylindrical tubes grown directly from flat glass substrates as well as spherical glow-discharge-polymer substrates were made using two-photon polymerization. The tube diameters were as small as 10-μm outer diameter and 4- to 5-μm inner diameter, and lengths were as long as 450 μm. Such structures could conceivably be used as fill tubes on inertial confinement fusion capsules. Two resin materials were examined, giving tubes with different flexibilities. One resin was an organic-inorganic hybrid silicon-zirconium sol gel, the second being Ormocomp, a commercially available ultraviolet-curable material. The strength of attachment of the zirconium-based sol gel tubes to their substrates was measured to be around 100 MPa. The times measured to remove uncured resins from high-aspect-ratio tubes during the development process were several hours.

Structural hydrogels

Research on hydrogel systems with structural features has aroused great interests due to its wide range of applications, including actuators, microfluidic units, synthetic adhesives, transplantable tissue organs, and cell scaffolds. This review article describes, with special emphasis, the design and fabrication of structural hydrogels with diversified geometric shapes and dimensions. These hydrogel structures include gradient gel, anisotropic gel, gel patterns, gel wrinkle, gel arrays and gel tubes. Several typical applications of such structural hydrogels are introduced, such as for controlling cell behavior, developing responsive actuators, and designing nature inspired bio-lubrication surface. Some perspectives on future development of structural hydrogel systems are provided.

Preliminary evaluation of a gel tube agglutination major cross-match method in dogs.

A major cross-match gel tube test is available for use in dogs yet has not been clinically evaluated. This study compared cross-match results obtained using the gel tube and the standard tube methods for canine samples. Study 1 included 107 canine sample donor-recipient pairings cross-match tested with the RapidVet-H method gel tube test and compared results with the standard tube method. Additionally, 120 pairings using pooled sera containing anti-canine erythrocyte antibody at various concentrations were tested with leftover blood from a hospital population to assess sensitivity and specificity of the gel tube method in comparison with the standard method. The gel tube method had a good relative specificity of 96.1% in detecting lack of agglutination (compatibility) compared to the standard tube method. Agreement between the 2 methods was moderate. Nine of 107 pairings showed agglutination/incompatibility on either test, too few to allow reliable calculation of relative sensitivity. Fifty percent of the gel tube method results were difficult to interpret due to sample spreading in the reaction and/or negative control tubes. The RapidVet-H method agreed with the standard cross-match method on compatible samples, but detected incompatibility in some sample pairs that were compatible with the standard method. Evaluation using larger numbers of incompatible pairings is needed to assess diagnostic utility. The gel tube method results were difficult to categorize due to sample spreading. Weak agglutination reactions or other factors such as centrifuge model may be responsible.

Stability of Routine Biochemical Analytes in Whole Blood and Plasma From Lithium Heparin Gel Tubes During 6-hr Storage.

The stability of biochemical analytes has already been investigated, but results strongly differ depending on parameters, methodologies, and sample storage times. We investigated the stability for many biochemical parameters after different storage times of both whole blood and plasma, in order to define acceptable pre- and postcentrifugation delays in hospital laboratories. Twenty-four analytes were measured (Modular® Roche analyzer) in plasma obtained from blood collected into lithium heparin gel tubes, after 2-6 hr of storage at room temperature either before (n = 28: stability in whole blood) or after (n = 21: stability in plasma) centrifugation. Variations in concentrations were expressed as mean bias from baseline, using the analytical change limit (ACL%) or the reference change value (RCV%) as acceptance limit. In tubes stored before centrifugation, mean plasma concentrations significantly decreased after 3 hr for phosphorus (-6.1% [95% CI: -7.4 to -4.7%]; ACL 4.62%) and lactate dehydrogenase (LDH; -5.7% [95% CI: -7.4 to -4.1%]; ACL 5.17%), and slightly decreased after 6 hr for potassium (-2.9% [95% CI: -5.3 to -0.5%]; ACL 4.13%). In plasma stored after centrifugation, mean concentrations decreased after 6 hr for bicarbonates (-19.7% [95% CI: -22.9 to -16.5%]; ACL 15.4%), and moderately increased after 4 hr for LDH (+6.0% [95% CI: +4.3 to +7.6%]; ACL 5.17%). Based on RCV, all the analytes can be considered stable up to 6 hr, whether before or after centrifugation. This study proposes acceptable delays for most biochemical tests on lithium heparin gel tubes arriving at the laboratory or needing to be reanalyzed.

Antibody Titers Study in Group O Blood Donors: Tube and Column Agglutination Techniques

Background: O blood group transfusions to patients of all blood groups has continued since long. Clinical significance of ABO antibody titre in ABO-I kidney transplantation is well known. Few studies done on group O blood/ apheresis donations, for detecting ABO antibody titers in collected plasma components. The passively acquired antibodies may destroy recipient’s own red cells and tissue grafts, cause acute hemolysis, hemoglobinemia, jaundice, progressive anemia, spontaneous agglutination, positive direct antiglobulin test and increased osmotic fragility of the patient’s red cells. Objective: To evaluate agglutinin levels in group O blood donations. Group O donor population, randomly selected and titrated using tube technique and gel card technique to identify titer levels for Anti A, Anti B, Anti AB antibodies. Both IgM and IgG titer levels evaluated. Methods: Plasma samples from 200 randomly selected blood group O donors were tested by ABO antibody titration using conventional tube technique and AHG gel card column agglutination technique (CAT). ABO antibody levels categorized as those higher than 16 and those lower than 16. After treatment with Dithiothretiol (DTT) for characterization of only IgG class, titres levels were again tested in same O group blood/apheresis donors. Statistical analyses performed using various tests. Results: Males constituted 88% of O group donors studied and 12% were females. ABO antibody titer categorized as 0 to ≤16 and titer >16 for both IgM and IgG antibody for Anti A, Anti B and Anti AB. Both test tube and CAT used for testing. Estimates of prevalence of titers by CAT: Anti A IgM ≤ 16 in 62%; >16 in 38% (p-value 16 in 68% (p-value 16 in 31% (p-value 16 in 65% (p-value 16 in 70% (p-value 16 in 73% (p-value 16 in 56% (p-value 16 in 56% (p-value 16 in 49% (p-value 16 in 64% (p-value 16 in 66% (p-value 16 in 96% (p-value < 0.001). No significant co-relation found between age and titer or gender and titer, by both technologies. Mean anti-A and anti-B and anti-AB titers in group O plasma were, respectively,163.28,113.42 and 166.77 for IgM antibody and 174.50,152.98 and 311.63 for IgG antibody by tube method and 34.01,33.30 and 63.77 for IgM Antibody,108.41,103.10 and 272.46 for IgG antibody by CAT (p < 0.0001). Conclusion: Study confirms that titration of ABO antibodies in blood banks will increase safety in non-identical ABO transfusions and transplants. No significant correlation established between titer and age or titer and gender.

A medical device-grade T1 and ECV phantom for global T1 mapping quality assurance-the T1 Mapping and ECV Standardization in cardiovascular magnetic resonance (T1MES) program.

BackgroundT1 mapping and extracellular volume (ECV) have the potential to guide patient care and serve as surrogate end-points in clinical trials, but measurements differ between cardiovascular magnetic resonance (CMR) scanners and pulse sequences. To help deliver T1 mapping to global clinical care, we developed a phantom-based quality assurance (QA) system for verification of measurement stability over time at individual sites, with further aims of generalization of results across sites, vendor systems, software versions and imaging sequences. We thus created T1MES: The T1 Mapping and ECV Standardization Program.MethodsA design collaboration consisting of a specialist MRI small-medium enterprise, clinicians, physicists and national metrology institutes was formed. A phantom was designed covering clinically relevant ranges of T1 and T2 in blood and myocardium, pre and post-contrast, for 1.5 T and 3 T. Reproducible mass manufacture was established. The device received regulatory clearance by the Food and Drug Administration (FDA) and Conformité Européene (CE) marking.ResultsThe T1MES phantom is an agarose gel-based phantom using nickel chloride as the paramagnetic relaxation modifier. It was reproducibly specified and mass-produced with a rigorously repeatable process. Each phantom contains nine differently-doped agarose gel tubes embedded in a gel/beads matrix. Phantoms were free of air bubbles and susceptibility artifacts at both field strengths and T1 maps were free from off-resonance artifacts. The incorporation of high-density polyethylene beads in the main gel fill was effective at flattening the B1 field. T1 and T2 values measured in T1MES showed coefficients of variation of 1 % or less between repeat scans indicating good short-term reproducibility. Temperature dependency experiments confirmed that over the range 15–30 °C the short-T1 tubes were more stable with temperature than the long-T1 tubes. A batch of 69 phantoms was mass-produced with random sampling of ten of these showing coefficients of variations for T1 of 0.64 ± 0.45 % and 0.49 ± 0.34 % at 1.5 T and 3 T respectively.ConclusionThe T1MES program has developed a T1 mapping phantom to CE/FDA manufacturing standards. An initial 69 phantoms with a multi-vendor user manual are now being scanned fortnightly in centers worldwide. Future results will explore T1 mapping sequences, platform performance, stability and the potential for standardization.Electronic supplementary materialThe online version of this article (doi:10.1186/s12968-016-0280-z) contains supplementary material, which is available to authorized users.

Sampling and Analytical Method for Alpha-Dicarbonyl Flavoring Compounds via Derivatization with o-Phenylenediamine and Analysis Using GC-NPD.

A novel methodology is described for the sampling and analysis of diacetyl, 2,3-pentanedione, 2,3-hexanedione, and 2,3-heptanedione. These analytes were collected on o-phenylenediamine-treated silica gel tubes and quantitatively recovered as the corresponding quinoxaline derivatives. After derivatization, the sorbent was desorbed in 3 mL of ethanol solvent and analyzed using gas chromatography/nitrogen-phosphorous detection (GC/NPD). The limits of detection (LOD) achieved for each analyte were determined to be in the range of 5–10 nanograms/sample. Evaluation of the on-tube derivatization procedure indicated that it is unaffected by humidities ranging from 20% to 80% and that the derivatization procedure was quantitative for analyte concentrations ranging from 0.1 μg to approximately 500 μg per sample. Storage stability studies indicated that the derivatives were stable for 30 days when stored at both ambient and refrigerated temperatures. Additional studies showed that the quinoxaline derivatives were quantitatively recovered when sampling up to a total volume of 72 L at a sampling rate of 50 cc/min. This method will be important to evaluate and monitor worker exposures in the food and flavoring industry. Samples can be collected over an 8-hour shift with up to 288 L total volume collected regardless of time, sampling rate, and/or the effects of humidity.

Influence of the collection tube on metabolomic changes in serum and plasma

Major threats in metabolomics clinical research are biases in sampling and preparation of biological samples. Bias in sample collection is a frequently forgotten aspect responsible for uncontrolled errors in metabolomics analysis. There is a great diversity of blood collection tubes for sampling serum or plasma, which are widely used in metabolomics analysis. Most of the existing studies dealing with the influence of blood collection on metabolomics analysis have been restricted to comparison between plasma and serum. However, polymeric gel tubes, which are frequently proposed to accelerate the separation of serum and plasma, have not been studied. In the present research, samples of serum or plasma collected in polymeric gel tubes were compared with those taken in conventional tubes from a metabolomics perspective using an untargeted GC–TOF/MS approach. The main differences between serum and plasma collected in conventional tubes affected to critical pathways such as the citric acid cycle, metabolism of amino acids, fructose and mannose metabolism and that of glycerolipids, and pentose and glucuronate interconversion. On the other hand, the polymeric gel only promoted differences at the metabolite level in serum since no critical differences were observed between plasma collected with EDTA tubes and polymeric gel tubes. Thus, the main changes were attributable to serum collected in gel and affected to the metabolism of amino acids such as alanine, proline and threonine, the glycerolipids metabolism, and two primary metabolites such as aconitic acid and lactic acid. Therefore, these metabolite changes should be taken into account in planning an experimental protocol for metabolomics analysis.

Trial of improved practices approach to explore the acceptability and feasibility of different modes of chlorhexidine application for neonatal cord care in Pemba, Tanzania.

BackgroundInfections are responsible for 30–40 % of 4 million neonatal deaths annually. Use of chlorhexidine (CHX), a broad-spectrum topical antiseptic with strong residual activity, for umbilical cord cleansing has been shown to reduce infections during the neonatal period. However, the challenge remains with regard to selection of best mode of CHX delivery. As a part of formative research, we undertook a qualitative study in Pemba Island as a pilot to explore the attitudes; beliefs and practices of the community and health workers related to delivery, newborn and cord care. During the second phase of formative research, we used Trials of Improved Practices (TIPs) methodology to explore the acceptance and impediments, for the three possible modes of chlorhexidine application- 100 ml bottle with cotton swab, 10 ml single use dropper bottle and 3 g single application squeeze tube containing gel, as an umbilical cord care intervention.MethodsIn this pilot study, 204 mother-newborn pairs were enrolled from hospital and community setting in Pemba, Tanzania using a randomized three period crossover design. Mothers/guardians, Trained Birth Attendants (TBA)/ medical staff and community health workers (CHWs) were requested to try three different modes of CHX application for cord cleaning. All participants were demonstrated the method of cord cleaning using all three modes of delivery; each delivery mode was used for 3 days and an interview was conducted on day 10 to collect summary of their experience. Acceptance and preference scores were calculated based on feedback from the participants.ResultsOf 204 mother-newborn pairs, 27 were lost to follow up. 177 mothers performed the intervention and applied CHX to the newborn cord for all 9 days. Mothers rated 10 ml dropper bottle (49.7 %) as most convenient in terms of ease and application. They selected 10 ml dropper bottle (44.6 %) as their first choice; gel tube (33.9 %) and 100 ml bottle (21.5 %) as their second and third choice. TBAs, medical staff and CHWs also preferred 10 ml dropper bottle (43.3 %) over 100 ml bottle (12.9 %) and gel (38.8 %).ConclusionsOverall acceptability of CHX application for cord cleansing was high. 10 ml single use dropper bottle was given highest preference for CHX application. An understanding of the attitudes, beliefs and cultural practices in the community and selection of the most acceptable mode of CHX delivery is essential to the design and implementation of the intervention trials examining the efficacy of CHX cord care in reducing neonatal mortality and subsequent implementation in the programs.Trial registrationClinicalTrials.gov NCT01528852 Registered February 3, 2012

Comparison of the clinical effects and complications of two operation methods for lacrimal duct obstruction

Objective To compare the clinical efficacy and complications of probing of lacrimal passages combined with retrograde intubation of Y shape silicone tube with or without Ofloxacin eye gel on treating lacrimal duct obstruction. Methods Eighty eyes of 75 cases of lacrimal duct obstruction who underwent surgeries in our hospital from 2012 to 2013 were investigated retrospectively.The success rate and complications of two operation methods were compared. Results All the patients were followed up for 3 months. The success rate of probing of lacrimal passages combined with retrograde intubation of Y shape silicone tube and Ofloxacin eye gel was higher than that of Y shape silicone tube intubation only, and the difference was statistically significant (χ2=4.694 P=0.03). It also significantly reduced the complications. Conclusion The probing of lacrimal passages combined with retrograde intubation of Y shape silicone tube and Ofloxacin eye gel can significantly reduce the early operative complications, and improve the success rate. Key words: Obstruction, lacrimal duct; Stentl, lacrimal duct; Intubation retrograde; Ofloxacin eye gel

A comparison of fluoride-oxalate and plain (serum gel) tube on glucose measurement

A continuing problem in the accurate measurement of glucose is its decline in concentration due to erythrocytic glycolysis after sampling, transport and processing. Eliminating this problem requires the use of an anti-glycolytic agent that can be added to the sampling tubes without altering cellular integrity while measuring blood glucose. This study was therefore conducted to compare fluorideoxalate and plain tube on glucose measurement at the Komfo Anokye Teaching Hospital. A total of 100 subjects were recruited from an adult population at the Komfo Anokye Teaching Hospital. Six milliliters of venous blood sample was collected from each patient and 1ml each was dispensed into three separate fluoride-oxalate and plain tubes and were centrifuged at different time intervals to obtain plasma and serum respectively. 1%, 4% and 8% of the subjects presented with hypoglycaemia at immediate, after 1 hour and 2 hours fluoride-oxalate while that of plain tubes were 3%, 6% and 14% respectively. 58%, 53% and 49% of the subjects presented with hyperglycaemia at immediate, after 1 hour and 2 hours for fluoride-oxalate while that of plain tubes were 58%, 49% and 47%. Decrease in glucose concentration after 1 hour and 2 hours in fluoride-oxalate tubes were 6.5% and 13% respectively while those in plain tubes were 8.9% and 16.7%. Though, fluoride-oxalate does not completely inhibit erythrocytic glycolysis within two hours, its effect when left on the bench at different time intervals does not show a significant change in test results. Plain tubes however show significant change in test results at different time intervals since they do not contain any antiglycolytic agents needed to preserve blood glucose.Keywords: Glucose estimation, preservative, serum gel, glucose oxidase, Ghana

Comparation of microcolumn gel test and tube anti-globulin test with IgG anti A(B)of pregnant women

Objective Compared study on microcolumn gel test(MGT)and tube anti-globulin test(TAT)in the detection of pregnant women IgG anti A(B)in the application of antibody and evaluate the application value of MGT in the prediction of HDN. Methods Choosed blood samples of 443 cases of O blood type pregnant women whose husband were not O blood type as the research object. Every specimen were tested by MGT method and TAT method, and the data were treated statistically. Results The positive rate of MGT method and TAT method were: 30%and 12.5% which had statistical significance(χ2=15.95,P<0.05). The difference was significant in positive cases titer distribution(t=15.13,P<0.01). Conclusion The micro column gel method is rapid, simple, sensitive and repeatable compared of tube anti-globulin test(TAT). Key words: IgG anti A(B); Microcolumn gel test; Tube anti-globulin test

Human papillomavirus (HPV) contamination of gynaecological equipment

ObjectiveThe gynaecological environment can become contaminated by human papillomavirus (HPV) from healthcare workers’ hands and gloves. This study aimed to assess the presence of HPV on frequently used equipment in...

Comparison of a direct enzymatic assay and polyacrylamide tube gel electrophoresis for measurement of small, dense low-density lipoprotein cholesterol.

Comparison of a direct enzymatic assay and polyacrylamide tube gel electrophoresis for measurement of small, dense low-density lipoprotein cholesterol.

Angiogenesis stimulated by novel nanoscale bioactive glasses

The ability of biomaterials to induce rapid vascular formation is critical in tissue regeneration. Combining recombinant angiogenic growth factors with bioengineered constructs have proven to be difficult due to several issues, including the instability of recombinant proteins, the need for sustained delivery and the dosage of factors. New formulations of bioactive glass, 58S nanosized bioactive glass (58S-NBG), have been reported to enhance wound healing in animal models better than the first generation of 45S5 Bioglass. Therefore, we investigated the effects of extracts of 58S-NBG and 80S-NBG on cultures of human umbilical vein endothelial cells (HUVECs). Cell viability was assessed by MTS assay. In vitro angiogenesis was measured using an ECM gel tube formation assay, and levels of mRNAs for five angiogenic related genes were measured by qRT-PCR. Extracts of 58S-NBG and 80S-NBG stimulated the proliferation of HUVECs, accelerated cell migration, up-regulated expression of the vascular endothelial growth factor, basic fibroblast growth factor, their receptors, and endothelial nitric oxide synthase, resulting in enhanced tube formation in vitro. The enhanced angiogenic response correlated with increased levels of Ca and Si in the extracts of 58S-NBG and 80S-NBG. The ability of 58S-NBG and 80S-NBG to stimulate angiogenesis in vitro provides alternative approaches for stimulating neovascularization of tissue-engineered constructs.

Observations of carbon export by small sinking particles in the upper mesopelagic

Carbon and nutrients are transported out of the surface ocean and sequestered at depth by sinking particles. Sinking particle sizes span many orders of magnitude and the relative influence of small particles on carbon export compared to large particles has not been resolved. To determine the influence of particle size on carbon export, the flux of both small (11–64μm) and large (>64μm) particles in the upper mesopelagic was examined during 5 cruises of the Bermuda Atlantic Time Series (BATS) in the Sargasso Sea using neutrally buoyant sediment traps mounted with tubes containing polyacrylamide gel layers and tubes containing a poisoned brine layer. Particles were also collected in surface-tethered, free-floating traps at higher carbon flux locations in the tropical and subtropical South Atlantic Ocean. Particle sizes spanning three orders of magnitude were resolved in gel samples, included sinking particles as small as 11μm. At BATS, the number flux of small particles tended to increase with depth, whereas the number flux of large particles tended to decrease with depth. The carbon content of different sized particles could not be modeled by a single set of parameters because the particle composition varied across locations and over time. The modeled carbon flux by small particles at BATS, including all samples and depths, was 39±20% of the modeled total carbon flux, and the percentage increased with depth in 4 out of the 5months sampled. These results indicate that small particles (<64μm) are actively settling in the water column and are an important contributor to carbon flux throughout the mesopelagic. Observations and models that overlook these particles will underestimate the vertical flux of organic matter in the ocean.

Native GELFrEE: A New Separation Technique for Biomolecular Assemblies

The cadre of protein complexes in cells performs an array of functions necessary for life. Their varied structures are foundational to their ability to perform biological functions, lending great import to the elucidation of complex composition and dynamics. Native separation techniques that are operative on low sample amounts and provide high resolution are necessary to gain valuable data on endogenous complexes. Here, we detail and optimize the use of tube gel separations to produce samples proven compatible with native, multistage mass spectrometry (nMS/MS). We find that a continuous system (i.e., no stacking gel) with a gradient in its extent of cross-linking and use of the clear native buffer system performs well for both fractionation and native mass spectrometry of heart extracts and a fungal secretome. This integrated advance in separations and nMS/MS offers the prospect of untargeted proteomics at the next hierarchical level of protein organization in biology.

Small-dense LDL/large-buoyant LDL ratio associates with the metabolic syndrome

ObjectiveHeterogeneous particles of intermediate-density lipoprotein (IDL) and low-density lipoprotein (LDL) vary in atherogenesis. We investigated the association between the metabolic syndrome (MetS) score and lipoprotein subclasses. Design and methodsA total of 260 outpatients were scored into six groups, based on their number of MetS components. Lipoprotein subclass determined by polyacrylamide tube gel electrophoresis separates IDL particles into three midbands (MID-A to C) and LDL into larger-buoyant (LDL1 and LDL2) and small-dense LDL (LDL3 to LDL6). ResultsMean concentrations of VLDL, MIDC, LDL2, and LDL3 to LDL6 positively correlated with increasing MetS score, but those of MIDA, LDL1 and HDL-C inversely correlated. LDL2 and LDL3 to LDL6 increased while MIDA and LDL1 decreased with increasing visceral fat, HOMA-IR, and triglycerides, with a reverse pattern for HDL-C. MIDB and MIDC were unchanged. By logistic regression, LDL1 and LDL3 to LDL6 significantly associates with the MetS score (odds ratio=0.957 and 1.077, respectively). The ratio of (LDL3 to LDL6)/LDL1 in the presence of HDL-C, showed the strongest association with MetS. ConclusionsRespective subpopulations of IDL and LDL particles can vary in their ability to identify MetS. Because of the most strongly associated with MetS, (LDL3 to LDL6)/LDL1 ratio is proposed as an excellent marker for evaluating lipid metabolic status in patient with MetS.

Method validation for methanol quantification present in working places

Given the widespread use of methanol by different industry sectors and high toxicity associated with this substance, it is necessary to use an analytical method able to determine in a sensitive, precise and accurate levels of methanol in the air of working environments. Based on the methodology established by the National Institute for Occupational Safety and Health (NIOSH), it was validated a methodology for determination of methanol in silica gel tubes which had demonstrated its effectiveness based on the participation of the international collaborative program sponsored by the American Industrial Hygiene Association (AIHA).