Application Of Test Material Research Articles

Comparison of Remineralization Effect of Casein Phosphopeptide Amorphous Calcium Phosphate and Sodium Fluoride on Enamel Surface after Orthodontic Debonding: An In vitro study

OBJECTIVE: To compare the result of "casein phosphopeptide amorphous calcium phosphate" with "sodium fluoride" (900 ppm) in remineralization of enamel after orthodontic debonding. METHODOLOY: This study was performed on premolars. Teeth were distributed into 3 groups A, B and C. The baseline microhardness of samples was measured. To create artificial demineralization, all samples were dipped in demineralizing solution. Surface microhardness (SMH) was re-measured for demineralization. Then, CPP-ACP was applied on teeth of gp B and NaF (900 ppm) was applied on teeth of gp C for remineralization. All teeth were cycled between deionized water and surface treatment for 12 weeks. The SMH of gp B and gp C was re-measured for remineralization. Paired t-test and Independent t-test were practiced to match MH before and after demineralization while keeping P value < 0.05. One way ANOVA was practiced to match mean difference in baseline MH and after demineralization. RESULTS: The baseline SMH of enamel decrease after demineralization. After application of test materials, mean SMH increased by 230.2 VHN and 207.5 VHN respectively. The %age of SMHR reveal the recovery rate of 41.2% in CPP-ACP and 19.1% in NaF group. CONCLUSION: For treating post orthodontic demineralized lesions, a remineralizing cream having casein phosphopeptide stabilized amorphous calcium phosphate is useful with some mineral and aesthetic improvements. KEYWORDS: Casein Phosphopeptide Amorphous Calcium Phosphate (CPP-ACP), Sodium Fluoride (NaF), Surface Microhardness (SMH), Vickers Hardness Number (VHN), Rmineralization.

Effectiveness evaluation of hemostatic materials in acute exposure <i>in vivo</i>

Aim: comparative assessment of the effectiveness of hemostatic materials in an acute experiment in vivo . Materials and methods. We studied samples of hemostatic materials TachoComb (No. 1), Gelita-Spon Standard (No. 2), Surgicel Fibrillar (No. 3), samples of hemostatic sponges developed jointly with LLC ”Lintex“ (St. Petersburg, Russia) based on sodium carboxymethyl cellulose ( Na-CMC): Na-CMC + Tranexamic acid, pressed (No. 4), Na-CMC + Tranexamic acid, uncompressed (No. 5), Na-CMC pressed (No. 6), Na-CMC uncompressed (No. 7). Rats under general anaesthesia were given a middle laparotomy, and the partial liver resection of the left liver lobe was simulated. The bleeding was stopped by application of test materials. Blood loss volume (blood volume absorbed by one sample), bleeding time were evaluated. We applied nonparametric criterion of Mann-Whitney ( p ≤ 0.05) to determination of reliability of differences. Results . The lowest values of the index ”Bleeding time“ are observed in experimental groups No. 4-No. 7. Among the samples of these groups there are the following statistically significant differences: the values of the samples of group No. 4 are 1.5 times higher than that of sample No. 5; 2.68 times – group No. 6; 2.41 times – groups No. 7. The values of samples of group No. 7 are 1.74 times less than samples of group No. 5 and 4 seconds more than in group No. 6. When comparing blood loss volume in investigated groups, fewer statistically significant differences are observed. But the values of the samples of group No. 2 significantly exceed the values of all experimental groups. Conclusion . The use of a local hemostatic agent based on Na-CMC (with and without the addition of tranexamic acid) in stopping bleeding after the partial liver resection in laboratory animals (rats) is no less than clinically introduced applicational hemostatic agents such as TachoComb, Gelita-Spon Standard and Surgicel Fibrillar.

Nutrient Leaching Loss of Pre-Treated Struvite and Its Application in Sudan Grass Cultivation as an Eco-Friendly and Sustainable Fertilizer Source

Struvite recovered from waste streams is considered as a sustainable alternative to commercial phosphate (P) fertilizers manufactured from P rock. In this study, struvite was recovered from swine wastewater and pre-treated as air-dried material (AM), microwave irradiated material (MM), oven-dried material (OM), and incinerated material (IM) to reduce the moisture content. Based on their solubility and crystalline nature, AM and IM were selected for further experiments. The nutrient leaching loss and fertilizing value of AM and IM were evaluated in comparison to commercial fused superphosphate (FSP) fertilizer. Soil columns were used to quantify ortho-phosphate (O-P) and ammonium nitrogen (NH4-N) leaching in soil from the test materials. Among the test materials, the average leaching rate of O-P for FSP and AM was significantly different from the control and IM (p < 0.05). The average leaching rate of NH4-N among the test materials did not show any significant difference (p > 0.05). Sudan grass growth was examined with standard (urea supplemented) and high (20x, without urea) application of test materials in pot and soil box trials, respectively, to study the fertilizing value AM and IM. There were no significant differences among the test materials, except for the control, in terms of growth rate and fresh and dry matter yield in the pot trials (p > 0.05). When AM, IM, and FSP were applied in increasing amounts (20x) without urea supplement, Sudan grass growth was 50% lower in IM and was found to be significantly different from AM and FSP (p < 0.05). The results suggest that struvite pre-treated as AM could be an effective sustainable and eco-friendly alternative to commercial P fertilizers and thus helps to ensure agricultural sustainability.

Mitragyna speciosa Korth standardized methanol extract induced short-term potentiation of CA1 subfield in rat hippocampal slices

Mitragyna speciosa Korth or ketum or kratom has long been used by local people in Thailand and Malaysia to treat various types of diseases and to boost energy. There is lack of information available on the effect of M. speciosa Korth in learning and memory function, therefore this study was conducted to understand its effect using a cellular model (hippocampus). The objective of this study was to delineate the effect of M. speciosa Korth standardized methanol extract (MS), we used extracellular recording in rat hippocampal slices in vitro. Acute hippocampal slices were prepared from 4 weeks-old male Sprague dawley rats. Field excitatory post-synaptic potentials (fEPSP) were investigated after the application of test materials in concentrations of 0.0001, 0.001, 0.005, 0.01, 0.05 and 0.1% dissolved in 0.1% DMSO. The 50% inhibitory concentration (IC50) of test material was then calculated. Superfusion of MS (all concentrations) produced irreversible fEPSP amplitude reduction with an IC 50 of 0.008%. The same concentration of MS (0.008%) prevented the induction of long-term potentiation (LTP) and induced only short-term potentiation (STP) in CA1 neurons. In the CA1 region of the hippocampus, reduced concentration-dependently glutamatergic transmission and blocked LTP at the IC50.

Radiation prevulcanized natural rubber latex: Cytotoxicity and safety evaluation on animal

Radiation prevulcanized natural rubber latex (RVNRL) was claimed to be more user friendly than natural rubber latex prevulcanized by sulphur curing system. The absence of Type IV allergy inducing chemicals in RVNRL make it a suitable material for manufacturing of many kinds of latex products, especially those come into direct contact with users. This paper reveals and discusses the findings of cytotoxicity test and safety evaluation on animal for RVNRL. The test was done on RVNRL films prepared by coagulant dipping method and RVNRL dipped products produced by latex dipped product manufacturers. Cytotocixity test was carried out on mammalian cell culture American Type Culture Collection CCL 81, Vero. Results indicated that no cytotoxic effect from RVNRL films and products was found on the cell culture. Two animal studies, namely dermal sensitization study and primary skin irritation study, were done on gloves made from RVNRL. Albino white guinea pigs were used as test subjects in dermal sensitization study and results showed no sensitization induced by the application of test material in the guinea pigs. Primary skin irritation study was done on New Zealand white rabbits and results showed that the product tested was not corrosive and was not a primary irritant

Interaction of Hydration, Aging, and Carbon Content of Soil on the Evaporation and Skin Bioavailability of Munition Contaminants

Water plays a key role in enhancing the permeability of human skin to many substances. To further understand its ability to potentially increase the bioavailabililty of soil contaminants, artificial sweat was applied to excised pig skin prior to dosing with munition-contaminated soils. Skin was mounted in chambers to allow simultaneous measurement of evaporation and penetration and to control air flow, which changed the dwell time of skin surface water within a l-h period post application of test materials. Additional variables included type of compound, aging of spiked soil samples, and carbon content of soil. To this end, the evaporation and skin penetration of C-14 labeled hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), 2,6-dinitrotoluene (26DNT), and 2,4,6-trinitrotoluene (TNT) were determined from two soil types, Yolo, having 1.2% carbon, and Tinker, having 9.5% carbon. RDX soil samples aged 27 mo and 62 mo were compared to freshly spiked soils samples. Similarly, 26DNT samples aged 35–36 mo and TNT samples aged 18 mo were compared to freshly spiked samples. Approximately 10 μg/cm2 of radiolabeled compound was applied in 10 mg/cm2 of soil. Radiolabel recovered from the dermis and tissue culture media (receptor fluid) was summed to determine percent absorption from the soils. Radiolabel recovered from vapor traps determined evaporation. Mean skin absorption of all compounds was higher for low-carbon soil, regardless of soil age and skin surface water as affected by air flow conditions. For 26DNT, a simultaneous increase in evaporation and penetration with conditions that favored enhanced soil hydration of freshly prepared samples was consistent with a mechanism that involved water displacement of 26DNT from its binding sites. A mean penetration of 17.5 ± 3.6% was observed for 26DNT in low-carbon soil, which approached the value previously reported for acetone vehicle (24 ± 6%). 26DNT penetration was reduced to 0.35% under dryer conditions and to 0.08% when no sweat was applied. When soil hydration conditions were not varied from cell to cell, air flow that favored a longer water dwell time increased penetration, but not evaporation, consistent with a mechanism of enhanced skin permeability from a higher hydration state of the stratum corneum. Profiles of 26DNT penetration versus air flow conditions were exponential for freshly prepared soil samples, suggesting strong and weak binding sites; corresponding profiles of 26DNT penetration from aged samples were linear, suggesting a conversion of weak to strong binding sites. Absorption and evaporation was less than 5% for TNT and less than 1% for RDX, regardless of soil type and age. Fresh preparations of RDX in Tinker soil and aged samples of TNT in Yolo soil showed a significant decrease in skin absorption with loss of surface moisture. The penetration rate of radiolabel into the receptor fluid was highest during the 1–2 h interval after dosing with 26DNT or TNT. High-performance liquid chromatography (HPLC) analysis of 26DNT in receptor fluid at maximum flux indicated no metabolism or breakdown. For TNT, however, extensive conversion to monoamino derivatives and other metabolites was observed. Relatively little radioactivity was found in the dermis after 26DNT and TNT applications, and dermal extracts were therefore not analyzed by HPLC. RDX was not sufficiently absorbed from soils to allow HPLC analysis. This study has practical significance, as the use of water for dust control at remediation sites may have the unintended effect of increasing volatilization and subsequent absorption of soil contaminants. Soil in contact with sweaty skin may give the same result. Skin absorption of 26DNT from soil was over 50-fold higher than the value for dryer skin and over 200-fold higher than the value obtained when there was no sweat application. While the hydration effect was less dramatic for RDX and TNT, soil contaminants more closely matching the physical properties of 26DNT may be similarly affected by hydration.

The Effects of Vehicles on the Human Dermal Irritation Potentials of Allyl Esters

Allyl esters, frequently used in the fragrance industry, often contain a certain percentage of free allyl alcohol. Allyl alcohol is known to have a potential for delayed skin irritation. Also present in the finished product are different solvent systems, or vehicles, which are used to deliver the fragrances based upon their intended application. This study was conducted to determine whether different vehicles affect the skin irritation potential of five different allyl esters. The allyl esters tested were allyl amyl glycolate, allyl caproate, allyl (cyclohexyloxy)acetate, allyl cyclohexylpropionate, and allyl phenoxyacetate in the vehicles diethyl phthalate, 3:1 diethyl phthalate:ethanol, and 1:3 diethyl phthalate:ethanol at concentrations of 0.1%, 0.5%, 1.0%, and 2.0% (w/w). A modified cumulative irritation test was conducted in 129 human subjects. Test materials (0.3 ml) were applied under occlusion to skin sites on the back for 1 day (24 h) using Hill Top chambers. Irritation was assessed at 1, 2, 4, and 5 days following application of test materials. Cumulative irritation scores varied considerably among test materials. There were no delayed irritation observations. The highest irritation scores were observed at the 2.0% concentration for all test materials. The irritation scores for allyl amyl glycolate, allyl (cyclohexyloxy)acetate, and allyl phenoxyacetate were highest in 1:3 diethyl phthalate:ethanol, thus the resulting calculated no-observed-effect levels, 0.12%, 0.03%, and 0%, respectively, were much lower for this vehicle compared to the diethyl phthalate vehicle, 0.33%, 0.26%, 0.25%, respectively. These data showed a trend for lower concentration thresholds to induce irritation when higher levels of ethanol were used in the vehicle.

The rdh bandage: hemostasis and survival in a lethal aortotomy hemorrhage model

Background The Rapid Deployment Hemostat (RDH) Bandage has been designed in collaboration with the Office of Naval Research for the treatment of bleeding because of extremity trauma. It is intended as both a battlefield and civilian severe trauma wound dressing. It consists of a specific formulation of Marine Polymer Technologies' proprietary hemostatic polymer poly-N-acetyl glucosamine, and has received FDA clearance. This study compares the hemostatic capabilities of the RDH Bandage with the standard U.S Army First Aid Field Bandage (AFAFB), utilizing a controlled lethal aortotomy model of hemorrhage. Materials and methods Aortic punch wounds 4 mm in diameter were made in the abdominal aortas of female Yorkshire White swine, and were allowed to bleed for 5 s before application of test materials. Test hemostats were applied to the wound with manual compression for 10 min. Total loss of blood was determined in each experiment. Bandages were removed at the end of 2 h, for those animals that survived, and the onset of re-bleeding was observed. Animals were monitored for an additional 30 min to assess survival following bandage removal. Hemostatic efficacy was judged by the total loss of blood, and the survival of the animals. Results Eighty percent of the animals treated with the RDH Bandage survived the study through the entire protocol, whereas only 40% of those treated with the Army First Aid Field Bandage survived the removal of manual compression step, and none survived following the removal of bandage after the 2 h observation/monitoring period. The average blood loss for the RDH Bandage treated animals was 234 ml, and the average blood loss for the Army First Aid Field Bandage treated animals was 1071 ml, through the observation/monitoring period. Conclusions The RDH Bandage is significantly superior to the standard issue U.S. Army First Aid Field Bandage in the control of hemorrhage in a lethal swine abdominal aortotomy hemorrhage model, resulting in decreased blood loss and increased survival.

Skin carcinogenicity of condensed asphalt roofing fumes and their fractions following dermal application to mice.

Condensed roofing asphalt fumes, generated at 316 degrees C, were collected by cold trap condensation and fractionated by preparative high performance liquid chromatography. Chemical classes in each of the fractions (A-E) were identified by gas chromatography/mass spectroscopy. The fractions, various combinations of fractions, the raw and heated asphalt, the neat asphalt fume and the reconstituted asphalt were tested for carcinogenicity, and three fractions were tested for cocarcinogenicity and tumor promotion with benzo[a]pyrene (BaP). The skin application carcinogenesis bioassay was conducted by twice weekly application of test materials in 0.05 ml of acetone/cyclohexane (1:1) for 104 weeks to 40 groups of male C3H/HeJ mice (30/group). Fractions were applied at a mass in proportion to their amount in the neat asphalt fumes. In addition, the neat asphalt fume was tested on Sencar mice to determine if this strain was more susceptible to the carcinogenic effects of the fumes. Condensed neat asphalt fumes produced similar and statistically significant increased tumor yields of papillomas and carcinomas in both strains as compared to respective vehicle controls. Recombination of all fractions resulted in a tumor response similar to neat asphalt fumes. Among individual fractions, C was most potent, followed by B. The other single fractions were without significant tumorigenic activity. Combinations containing fractions B and C were most active among the mixtures that were assayed and no evidence of enhancement of tumorigenesis in the mixtures was found. No significant cocarcinogenic or tumor promoting activity was observed with fractions A, D, or E and BaP. Raw unheated asphalt produced a few tumors in C3H mice, but no tumors were seen when raw asphalt heated to 316 degrees C, with the fumes permitted to escape, was applied.

Apple, Codling Moth Control, 1985

Abstract Test materials were applied to individual 7-year-old trees as single units replicated 4 times in a randomized complete block design. Trees were sprayed by handgun to run-off using a 7 gpm John Bean sprayer operating at 350 psi at about 400 gpa. The application of test materials was timed according to phenology data provided by Washington State Extension Service (see WSU Extension Bulletin 1072). The insect growth regulators F4999 and Dimilin were applied at the onset of laying at 43 degree-days (base 50°F) from first moth catch (Biofix). The first Guthion treatment was applied at the start of egg hatch at 226 degree-days from Biofix. Treatments were evaluated by examining 50 fruit per replication at harvest on 25 Sept for worm stings and entries. Average monthly temperatures were: May 56.7°F, Jun 61.8°F, Jul 71.6°F, Aug 64.3°F, Sep 55.2°F. Monthly rainfall in inches was: May 0.48, Jun 2.13, Jul 0.1, Aug 0.56, Sept 2.91.

Citrus Red Mite Pesticide Efficacy Tests in Riverside, 1985

Abstract Acaricides were tested for control of citrus red mite populations in Riverside, CA. A completely-randomized design was used with 8 single-tree replicates per treatment. Trees were assigned to treatments based on precount densities to minimize within-treatment variation prior to the application of test materials. Applications were made on 22 and 23 Apr when mite densities were moderately high. Materials were applied with a handgun at 450 psi (ca 10 gal/tree, 1000 gpa) using a John Bean sprayer. Counts of live, adult female mites from two 4-leaf terminals per tree quadrant (total of 32 leaves per tree) were made weekly until mite populations naturally declined due to the onset of high (>37°C) daily temperatures in late May.

Sensitized bean first internode bioassay for auxins and brassinosteroids

The bean first internode bioassay ofMeudt andBennett (Physiol. Plant.44: 422–428, 1978) is based on the curvature of bean internode sections after unilateral application of test material near to their base. The test was also used for estimation of biological activity of brassinosteroids which enhance the effect of auxin. Sensitivity of the assay to both IAA and 24-epibrassinolide was increased 1000 and 100 times, respectively, when internode sections were incubated in morphologically inversed position. Under these conditions test material was applied to the young auxin-sensitive morphologically apical internode tissues and auxin was basipetally translocated to the zone of curvature. Using this bioassay as little as 10 fmol of IAA and 1 pmol of 24-epibrassinolide can be estimated.

Apple, Late Season Control of The Leafroller Complex, 1982

Abstract Mature York trees on semi-dwarf rootstocks were selected early in the growing season for this test. Imidan 50W was applied in the first 5 cover sprays at 3 lb/A in 100 gal water with a conventional airblast sprayer. Test materials were applied on Aug 19 and Sep 2 when late season leafrollers were active. Sprays were applied to runoff using a Bean 35 gal/min hydraulic sprayer operating at 400 psi. Mite populations were evaluated on Jul 19 and found to be at low levels. An Aug 30 evaluation, following the first application of test materials, showed mites to be increasing slightly, but not to critical levels for this date. Fruit evaluations were made at harvest, Oct 11. Fifty fruit from each of the four replicates per treatment and examined for leaf-roller injury. The injuries were categorized as having occurred early (1st generation) or late in the season following commencement of the test.

Dwarf Evergreen Euonymus, Hemispherical Scale Control, 1979

Abstract Thirty six 8-10 inch tall, container-grown dwarf evergreen euonymus, heavily infested with hemispherical scale (300-400 per 2 inch section of growing tip), were selected for treatment. Test plants were growing in 6 inch pots. All stages of hemispherical scale were present. A single application of test materials was made out-of-doors Jun 18'79. Chevron spray sticker was added to all treatments at the rate of 2.4 ml/gal of spray mixture. Plants were sprayed to run-off using compressed air sprayers. Treatments were replicated 3 times, one plant constituting a replication. Plants were allowed to dry and then were returned to a plastic greenhouse. Mortality was determined Jul 3'79 by counting 100 individuals per plant. Counts were made with the use of a stereo-microscope by examining each scale insect and scoring it as living if normally-colored and full-bodied or dead if it was discolored and shriveled or dried.

A Portable ULV System for Aerial Application of Test Materials to Small Plots

A Portable ULV System for Aerial Application of Test Materials to Small Plots