Filter Paper Strips Research Articles

Matrix Metalloproteinase-8 And Interleukin-1Β In Gingival Fluid Of Children In The First Three Months Of Orthodontic Treatment With Fixed Appliances

In orthodontic treatment remodeling of periodontal space is concomitant with the movement of teeth. Matrix metalloproteinase-8 and interleukin-1beta are key markers of the initial tissue reaction in the processes of remodeling. The gingival fluid is the medium where changes in the profile and levels of these mediators occur. The AIM of this study was to investigate the levels of matrix metalloproteinase-8 and interleukin-1beta in gingival fluid samples during the first 3 months of orthodontic treatment with fixed appliances in children. Twelve children receiving brackets treatment were included in the study; 48 samples of gingival fluid collected from one representative tooth of these children were measured once before placing the brackets, then at 24 hours, at 1 week, and at 3 months. We measured the amount of gingival fluid and the levels of matrix metalloproteinase-8 and interleukin-1beta. Filter paper strips were used to collect gingival fluid. After eluting them we made a quantitative analysis of the biomarkers, matrix metalloproteinase-8 and interleukin-1beta, using the solid-phase enzyme immunoassay (ELISA). The results showed a slight drop in the levels of both markers compared with baseline values and an increase at three months of orthodontic treatment. A similar tendency was observed in the flow of gingival fluid. Quantitative analysis of matrix metalloproteinase-8 and interleukin-1beta in gingival fluid samples is potentially a non-invasive method by which orthodontists can get information about the remodeling processes in the periodontium during orthodontic treatment thus controlling and limiting them within physiological boundaries.

Electrochemical detection of Pb and Cd in paper-based microfluidic devices

Filter paper strips combined with screen-printed carbon electrodes (SPCE) were used in the assembly of a microfluidic device for detecting Pb(II) and Cd(II) in aqueous samples. The portable microfluidic device (with direct electrochemical detection) was tested for direct quantification of multiple analytes (Pb(II) and Cd(II)) in contaminated aqueous samples without pretreatment. Square wave anodic stripping voltammetric (SWASV) signal was greatly enhanced and displayed excellent analytical performance for Pb(II) and Cd(II) detection (from 0 to 100 ppb) with low limit of detection of 2.0 and 2.3 ppb, respectively. The proposed electrochemical devices also exhibited good selectivity and stability for analyses of real samples of gas dissolved salty soda water and ground water with physical contamination. The device is simple, low-cost, easy-to-fabricate and portable. This analytical device has the possibility of being useful for point-of-care applications in environmental monitoring, public health and food safety.

Gingival crevicular fluid volume evaluation in patients with controlled periodontal disease submitted to orthodontic treatment

BackgroundThis randomized study aimed at evaluating whether orthodontic tooth movement can induce detectable changes in gingival crevicular fluid (GCF) volume in patients with controlled periodontal disease. MethodsTen patients (8 women and 2 men, mean age of 46.2±10.4 years) with controlled periodontal disease and flared incisors were included in the study. Gingival crevicular fluid samples were collected from the mid-palatal and mid-lingual sites of 1 central and 1 lateral incisor of each arch from each patient for a total of 4 individual samples per patient. These sites were selected to represent the pressure side of the applied forces (movement sites). Samples obtained from the arch without the appliance served as controls. Samples were collected at 1 week before orthodontic activation (–7d); right before the orthodontic appliance activation (0); after 1 and 24hours; and after 7, 14, and 21 days of the activation. Filter paper strips were used in combination with a Periotron for GCF volume measurements. All patients received hygiene instructions and a kit containing toothbrush, fluoride dentifrice, and gluconate chlorhexidine 0.12% mouthwash to be used during all experiment. ResultsThere were no statistically significant differences over time in the GCF volume for any samples from the two groups. When the two groups were compared, there were no statistically significant differences in the GCF volume at any time point. ConclusionsThe GCF volume could not be associated to orthodontic movement in teeth with controlled periodontal disease.

The Pros and Cons of Airway Lining Fluid Composition Analysis

The Pros and Cons of Airway Lining Fluid Composition Analysis

External apical root resorption and the release of interleukin-6 in the gingival crevucular fluid induced by a self-ligating system

The aim of this study was to investigate the amount of external apical root resorption (EARR) and the release of interleukin (IL)-6 in the gingival crevicular fluid (GCF) in subjects treated with a low-force low-friction system. Sixty patients were assigned to two groups of thirty patients for each: one group received treatment with self-ligating brackets and the other with conventional ligated edgewise brackets. All patients were treated with extraction of the maxillary first premolars. The EARR of the maxillary central incisors was evaluated on the periapical radiographs and cephalograms, taken before and after orthodontic treatment. The GCF was also collected non-invasively from the mesial and distal sides of central incisors by using filter paper strips before and after orthodontic treatment. Enzyme-linked immunosorbent assay (ELISA) kits were used to determine the IL-6 levels in the GCF samples. A significant difference was found in the amount of EARR between the patients with self-ligating brackets and conventional brackets. The mean amount of EARR was significantly lower for self-ligating brackets than conventional brackets (p < 0.05). The GCF levels of IL-6 for the patients with self-ligating brackets appliance were significantly lower than for those with the conventional brackets (p < 0.05). These results show that the mean amount of EARR and the GCF levels of IL-6 were significantly lower in the patients treated using low-force low-friction appliances than conventional brackets. Therefore, self-ligating brackets may be a useful system for reducing inflammation and EARR.

Charcoal filter paper improves the viability of cryopreserved filamentous ectomycorrhizal and saprotrophic Basidiomycota and Ascomycota

We assessed viability of 18 strains of filamentous ectomycorrhizal and saprotrophic basid-iomycetes and ascomycetes after cryopreservation with a novel technique based on charcoal filter paper strips (CFS). The results indicate that axenic fungal cultures grown on CFS recovered from freezing within a few days, even though none survived cryopreservation by the conventional straw method. Fungal growth on CFS was more vigorous, with morphological differentiations such as rhizomorphs and an increased amount of aerial mycelia compared to the unamended culture media. Accordingly CFS allows the cryopreservation of a wide range of rare and important ectomycorrhizal and saprotrophic fungi, which hitherto were difficult to revive from liquid nitrogen storage with the conventional and widely applied straw technique.

Clinical guidelines for diagnosing and managing ocular manifestations in children with mucopolysaccharidosis

The mucopolysaccharidoses (MPS) are a group of rare lysosomal storage disorders characterized by the accumulation of glycosaminoglycans in several tissues and organs. This accumulation results in an array of clinical manifestations and premature death in severe cases. Ocular problems are very common in children with MPS and may involve the cornea, sclera, trabecular meshwork, retina, optic nerve and also the posterior visual pathways. The aims of this study are to give an overview of ocular problems in MPS and to provide clinical guidelines for paediatric ophthalmologists for early diagnosis and management of ocular manifestations in children with MPS. Diagnostic problems may arise in children with severe corneal clouding, hampering visualization of the fundus. Intraocular pressures may be falsely high, even leading to suspicion and unnecessary pressure-lowering treatment. Simple interventions such as the use of prescription glasses or photochromatic glasses can considerably improve quality of life in children with MPS.

Evaluation of Nobuto Filter Paper Strips for the Detection of Avian Influenza Virus Antibody in Waterfowl

Evaluation of Nobuto Filter Paper Strips for the Detection of Avian Influenza Virus Antibody in Waterfowl

Exploring the Impact of Clinical Anticoagulants on Venous Thrombosis Stability Using a Novel Intravital Murine Model

Abstract 1246 Background:Thrombus stability influences the progression of deep vein thrombosis to a potentially fatal pulmonary embolism (PE) event. Anticoagulants are clinically administered to treat venous thrombosis. However, the effect of anticoagulants on thrombus stability remains unknown. Objective:We developed a novel intravital mouse model to explore the hypothesis that administration of clinical anticoagulants would decrease early thrombus stability, thereby potentially increasing PE risk. Methods:The trachea and jugular vein were cannulated, and the femoral vein isolated, in wild type C57/Bl6 female mice. Platelets were labeled in vivo using anti-mouse CD41 Fab fragments conjugated to Alexa Fluor-488. A 1 × 2 mm filter paper strip, saturated in 4% ferric chloride, was applied to the femoral vein for 5 minutes to induce thrombus formation. Wide-field fluorescent microscopy was used to quantify thrombus stability. Stability was related to the number of embolic events and loss of platelet intensity captured downstream of the thrombus at 5, 15, 30, 45, and 60 minutes post thrombus formation. Results:The mean number of embolic events and loss of platelet intensity decreased over time in wild type mice (n = 12). This suggested that thrombus stability increases over time. Anticoagulants were administered via a jugular vein catheter, at 12 minutes post thrombus formation, to assess impact on embolization. The anticoagulants examined were hirudin (8U/g mouse body weight), unfractionated heparin (UFH) (0.1U/g), a covalent antithrombin-heparin complex (ATH) (0.08U/g), and fondaparinux (0.1μg/g). We observed an overall a) increase in the number of embolic events and b) increase in platelet intensity lost over time in mice injected with hirudin (n = 12) and UFH (n = 12) when compared to untreated wild type control mice. The total number of embolic events occurring over one hour substantially increased in the hirudin-treated group (p = 0.09), which was also associated with an overall increase in total platelet intensity (p = 0.08), compared to untreated control mice. In addition, there was an increase in the total number of embolic events compared to the UFH-treated group (p = 0.09). Administration of hirudin, a direct thrombin inhibitor (DTI), and UFH, an indirect thrombin inhibitor, could result in decreased venous thrombus stability. However, it appears that the DTI is associated with greater thrombus instability. In the ATH-treated group (n = 12), an increase in embolic events at 15 minutes was observed, followed by a decrease in embolization. ATH could initially disrupt thrombus stability through inhibition of fibrin-bound thrombin, before acting in a stabilizing manner. Administration of fondaparinux (n = 6), an indirect factor-Xa inhibitor, demonstrated an overall decrease in embolic events and platelet intensity lost over time. When compared to control groups, there was a significant decrease in total number of embolic events and total amount of platelet intensity lost in the fondaparinux group (p < 0.05). Use of a factor-Xa inhibitor appears to enhance thrombus stability more effectively in comparison to direct and indirect thrombin inhibitors. Conclusion:Use of anticoagulants that inhibit thrombin predominantly could decrease early thrombus stability and potentially increase the likelihood of a PE event. Disclosures:No relevant conflicts of interest to declare.

A dye binding method for measurement of total protein in microalgae

Protein is a large component of the standing biomass of algae. The total protein content of algae is difficult to measure because of the problems encountered in extracting all of the protein from the cells. Here we modified an existing protein assay to measure total protein in microalgae cells that involves little or no extraction of protein from the cells. Aliquots of fresh or pretreated cells were spotted onto filter paper strips. After drying, the strips were stained in a 0.1% (w/v) solution of the protein stain Coomassie Brilliant Blue R-250 for 16 to 24 h and then destained. The stained protein spots were cut out from the paper, and dye was eluted in 1% (w/v) sodium dodecyl sulfate (SDS). Absorbance at 600 nm was directly proportional to protein concentration. Cells that were recalcitrant to taking up the dye could be either heated at 80 °C for 10 min in 1% SDS or briefly sonicated for 3 min to facilitate penetration of the dye into the cells. Total protein measured in Chlorella vulgaris using this method compared closely with that measured using the total N method. Total protein concentrations were measured successfully in 12 algal species using this dye binding method.

Gustatory and olfactory dysfunction in older adults: a national probability study

Olfactory and gustatory functions have not been well characterized in older adults in the US. Consequently, their relationships to sociodemographic characteristics, as well as physical and mental health, were studied in a large national probability sample using brief validated tests of chemosensory function. A five-odour identification test and taste-impregnated strips of filter paper (sweet, sour, bitter, and salty) assessed the ability to identify chemosensory stimuli. Severe gustatory dysfunction was more prevalent than severe olfactory dysfunction. Age, education and sex were independently associated with performance on both the olfactory and gustatory identification tasks. Higher scores were associated with female sex, higher level of education, and lower age. Odour identification scores exhibited a positive, albeit weak, correlation with BMI, and food-related odours were better identified than non-food odours. In addition, odour identification performance was also negatively associated with depressive symptoms. These data demonstrate a high prevalence of severe gustatory and, to a somewhat lesser extent, olfactory dysfunction in a population-based sample and demonstrate that even brief tests are capable of detecting correlations between both chemical senses and relevant health measures outside a clinical setting.

Glucose-Driven Fuel Cell Constructed from Enzymes and Filter Paper

A glucose-driven enzymatic filter-paper fuel cell is described. A strip of filter paper coated with carbon nanotubes and the glucose oxidase enzyme functions as the anode of the enzyme fuel cell. Another strip of filter paper coated with carbon nanotubes and the laccase enzyme functions as the cathode. Between the anode and the cathode, a third strip of filter paper is placed that holds the glucose, which is the fuel, and that allows the transport of ions. The design of the cell is simple, and all the materials used for the construction are readily available and biocompatible. The cell utilizes the oxidation of glucose to generate electricity and is useful to demonstrate how chemical energy can be converted to electrical energy.

Immobilized pH gradient-driven paper-based IEF: a new method for fractionating complex peptide mixtures before MS analysis

IntroductionThe vast difference in the abundance of different proteins in biological samples limits the determination of the complete proteome of a cell type, requiring fractionation of proteins and peptides before MS analysis.MethodsWe present a method consisting of electrophoresis of complex mixtures of peptides using a strip of filter paper cut into 20 sections laid end to end over a 24-cm-long IPG strip, the pH gradient of which would drive the electrophoresis. Peptides absorbed onto individual paper pads after electrophoresis are subsequently recovered into a buffer solution, thus dividing a complex peptide mixture according to pI into 20 liquid fractions. This paper-based IEF method (PIEF) was compared side-by-side with a similar but liquid-based Offgel electrophoresis (OGE) by analyzing iTRAQ-labeled peptide mixtures of membrane proteins from four different cell types.ResultsPIEF outperformed OGE in resolving acidic peptides, whereas OGE did a better job in recovering relatively basic peptides. OGE and PIEF were quite comparable in their coverage, identifying almost equal number of distinct proteins (PIEF =1174; OGE = 1080). Interestingly, however, only 675 were identified by both of them, each method identifying many unique proteins (PIEF = 499; OGE = 415). Thus, the two methods uncovered almost 40% more proteins compared to what is obtained by only one method. Conclusion: This initial investigation demonstrates the technical feasibility of PIEF for complementing OGE. PIEF uses standard IPG IEF equipment, requires no specialized apparatus (e.g., OGE fractionator) and may be integrated into peptide mapping strategies for clinical samples.

Resistência ao jejum de Rhodnius stali Lent, Jurberg &amp; Galvão, 1993 (Hemiptera, Reduviidae, Triatominae) em condições de laboratório

The objective of this study was to evaluate the resistance of Rhodnius stali Lent, Jurberg & Galvao, 1993 to food deprivation under laboratory conditions at mean environmental temperature and humidity rates. Recently laid eggs from previously separated pairs were transferred to 50 mL propylene assay tubes with screw caps wrapped with filter paper. A strip of filter paper was included inside to increase the insects' contact area and remove excess humidity. Specimens were isolated, identified, and observed after hatching until they died, having received only one feeding. The mean resistance to food deprivation was 23.45 ± 6.42; 40.52 ± 22.57; 70.39 ± 38.46; 119.6 ± 51.44, and 160.0 ± 49.44 days for the 1st to 5th stages, respectively. Adult males resisted for 52.65 ± 12.16 days, and females resisted for 46.50 ± 18.05 days.

Thrombotic distal middle cerebral artery occlusion produced by topical FeCl(3) application: a novel model suitable for intravital microscopy and thrombolysis studies.

Intravital or multiphoton microscopy and laser-speckle imaging have become popular because they allow live monitoring of several processes during cerebral ischemia. Available rodent models have limitations for these experiments; e.g., filament occlusion of the proximal middle cerebral artery (MCA) is difficult to perform under a microscope, whereas distal occlusion methods may damage the MCA and the peri-arterial cortex. We found that placement of a 10% FeCl(3)-soaked filter paper strip (0.3 × 1 mm(2)) on the duramater over the trunk of the distal MCA through a cranial window for 3 minutes induced intraarterial thrombus without damaging the peri-arterial cortex in the mouse. This caused a rapid regional cerebral blood flow decrease within 10 minutes and total occlusion of the MCA segment under the filter paper in 17±2 minutes, which resulted in a typical cortical infarct of 27±4 mm(3) at 24 hours and moderate sensorimotor deficits. There was no significant hemispheric swelling or hemorrhage or mortality at 24 hours. Reperfusion was obtained in half of the mice with tissue plasminogen activator, which allowed live monitoring of clot lysis along with restoration of tissue perfusion and MCA flow. In conclusion, this relatively simple and noninvasive stroke model is easy to perform under a microscope, making it suitable for live imaging and thrombolysis studies.

Arrestin-2 Differentially Regulates PAR4 and ADP Receptor Signaling in Platelets

Arrestins can facilitate desensitization or signaling by G protein-coupled receptors (GPCR) in many cells, but their roles in platelets remain uncharacterized. Because of recent reports that arrestins can serve as scaffolds to recruit phosphatidylinositol-3 kinases (PI3K)s to GPCRs, we sought to determine whether arrestins regulate PI3K-dependent Akt signaling in platelets, with consequences for thrombosis. Co-immunoprecipitation experiments demonstrate that arrestin-2 associates with p85 PI3Kα/β subunits in thrombin-stimulated platelets, but not resting cells. The association is inhibited by inhibitors of P2Y12 and Src family kinases (SFKs). The function of arrestin-2 in platelets is agonist-specific, as PAR4-dependent Akt phosphorylation and fibrinogen binding were reduced in arrestin-2 knock-out platelets compared with WT controls, but ADP-stimulated signaling to Akt and fibrinogen binding were unaffected. ADP receptors regulate arrestin recruitment to PAR4, because co-immunoprecipitates of arrestin-2 with PAR4 are disrupted by inhibitors of P2Y1 or P2Y12. P2Y1 may regulate arrestin-2 recruitment to PAR4 through protein kinase C (PKC) activation, whereas P2Y12 directly interacts with PAR4 and therefore, may help to recruit arrestin-2 to PAR4. Finally, arrestin2(-/-) mice are less sensitive to ferric chloride-induced thrombosis than WT mice, suggesting that arrestin-2 can regulate thrombus formation in vivo. In conclusion, arrestin-2 regulates PAR4-dependent signaling pathways, but not responses to ADP alone, and contributes to thrombus formation in vivo.

FILTER-PAPER BLOOD SAMPLES FOR ELISA DETECTION OF BRUCELLA ANTIBODIES IN CARIBOU

We evaluated blood collected on Nobuto filter-paper (FP) strips for use in detecting Brucella spp. antibodies in caribou. Whole blood (for serum) and blood-saturated FP strips were obtained from 185 killed arctic caribou (Rangifer tarandus groenlandicus). Sample pairs (serum and FP eluates) were simultaneously tested in duplicate using competitive enzyme-linked immunosorbent assay (c-ELISA) and indirect ELISA (i-ELISA) for Brucella spp. Prior work based on isolation of Brucella spp. revealed sensitivity (SE) and specificity (SP) of 100% and 99%, respectively, for both these serum assays in caribou. Infection status of the animals in the current study was unknown but recent sampling had revealed clinical brucellosis and >40% Brucella antibody prevalence in the herd. To assess the performance of FP relative to serum in these assays, serum was used as the putative gold standard. On both assays, the findings for duplicate runs (A and B) were similar. For c-ELISA run A, the FP Brucella prevalence (47%) was lower than serum prevalence (52%), with SE 89% (95% confidence interval [CI]: 82-95%) and SP 99% (97-100%). For i-ELISA run A, serum and FP Brucella prevalence rates were identical (43%), and the SE and SP of FP testing were 100% and 99% (97-100%), respectively. The findings suggest better FP test performance with i-ELISA than with c-ELISA; however, i-ELISA does not distinguish cross-reacting antibodies induced by Brucella vaccination or exposure to certain other Gram-negative pathogens. Results for duplicate FP eluates (prepared using separate FP strips from each animal) were strongly correlated for both protocols (r=0.996 and 0.999 for c-ELISA and i-ELISA, respectively), indicating minimal variability among FPs from any individual caribou. Dried caribou FP blood samples stored for 2 mo at room temperature are comparable with serum for use in Brucella spp. c-ELISA and i-ELISA. Hunter-based FP sampling can facilitate detection of disease exposure in remote regions and under adverse conditions, and can expand wildlife disease surveillance across temporospatial scales.

Evaluation of Nobuto Filter Paper Strips for the Detection of Avian Influenza Virus Antibody in Waterfowl

The utility of using Nobuto paper strips for the detection of avian influenza antibodies was examined in mallards (Anas platyrhynchos) experimentally infected with low pathogenic avian influenza viruses. Blood was collected 2 wk after infection and was preserved either as serum or whole blood absorbed onto Nobuto strips. Analysis of samples using a commercially available blocking enzyme-linked immunosorbent assay revealed comparable results (> or = 96% sensitivity for all methods) between sera stored at -30 C and the Nobuto strip preservation method even when the Nobuto strips were stored up to 3 mo at room temperature (RT). Significant differences were detected in the ratio of sample absorbance to negative control absorbance for Nobuto strips stored at RT compared with sera stored at -30 C, although these differences did not affect the ability of the test to reliably detect positive and negative samples. Nobuto strips are a convenient and sensitive alternative to the collection of serum samples when maintaining appropriate storage temperatures is difficult.

The Expression &lt;i&gt;In Vitro&lt;/i&gt; and Application on Cellulose Degradation of LeEXP2

Cellulosic ethanol has become a hotspot in recent years. However, its crystal structure makes the efficiency of cellulosic degradation by cellulase very low. Traditional ways to disrupt of connection between microfiber consumes a deal of energy and would pollute the environment as well. Plant expansin is known to loosen the plant cell wall, and might provide a synergistic effect on the activities of cellulase. Whereas, the expression level of expansin in plants has been a limit to the functional study and application in cellulose degradation. Thus, it is essential to screen expansin proteins for biomass deconstruction and express them effectively in vitro. Therefore, we cloned expansin gene LeEXP2 from tomato leaves and obtained recombinant Pichia yeast strains integrated with LeEXP2 gene. When incubated in the same culture condition, recombinant strains can secrete the LeEXP2 protein to extracellular medium, while wild-type strain cannot. Preliminary cellulose degradation experiment confirmed that the secreted protein had synergistic the effect of cellulose hydrolysis by cellulase. The experiments of extension strength of filter-paper strips shows that LeEXP2 has a texture-loosening effect on the filter paper, which might make cellulase prone to access cellulose. Above data suggests that LeEXP2 could be expressed effectively in vitro and might become a kind of potential biochemical agent applied in cellulosic biomass conversion for bioenergy production.

Receptor activator of nuclear factor kappa B ligand (RANKL) levels in peri-implant crevicular fluid.

Receptor activator of nuclear factor kappa B ligand (RANKL) is one of the key cytokines in the induction of osteoclastogenesis both in vitro and in vivo. Several reports indicated the presence of sRANKL in gingival crevicular fluid of patients with periodontal diseases. To determine the presence of RANKL in peri-implant crevicular fluid samples of implants with peri-implantitis, peri-implant mucositis and healthy controls. In this study, 40 implants were categorized as clinically healthy, peri-implant mucositis and peri-implantitis according to the clinical and radiographic findings. Filter paper strips were used to collect peri-implant crevicular fluid for 30 seconds in the base of the crevice/pocket. Peri-implant crevicular fluid (PICF) samples were obtained from buccal and lingual aspects of implants. Plaque index, probing depth, gingival index and bleeding on probing were recorded at six sites per implant. Enzyme-linked immunosorbent assay (ELISA) was performed to determine the PICF levels of sRANKL. There were no statistically significant differences in sRANKL concentration between healthy group, peri-implant mucositis and periimplantitis (p=0.12). There were also no statistical correlation between the concentration of sRANKL and probing pocket depth (R=0.051, p=0.65), or any of the other clinical regarding (p>0.05). No differences between the mean sRANKL concentration in the buccal and lingual sites were found (p=0.693). Our results may suggest that peri-implant crevicular fluid analysis of sRANKL in conjunction with some other osteoclastogenic mediators could be further investigated in further well-designed prospective longitudinal studies on a larger-scale sample size in the evaluation of dental implants.