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Replacing radioactively labeled probes by nonradioactive ones and detection by chemiluminescence instead of colorimetry allows a nonhazardous handling and offers the possibility of easily reprobing filters in Southwestern analysis. Using the described procedure, we were able to determine the molecular weight of DNA-binding proteins and achieve a high signal-to-noise ratio.
The purpose of the case study was to design an approach involving the clinical use of glycated hemoglobin (GH) in patients with diabetes mellitus (DM). 139 patients with DM, types 1 and 2, were examined. GH was quantified by 4 methods, i.e. immunochemistry, colorimetry, by oxalic and phosphoric acids and by isoelectrofocusing. It was revealed by correlation and regression assays that the GH level made a non-linear bond and depended to a great extent on a daily glucosuria, daily proteinuria, total serum cholesterol, body weight index and disease duration. Whereas no such bond was found for accidental pre- and postprandial glycemias. The conclusion is that, with due respect to a comparative analysis of different techniques applicable to GH quantification, the discussed index still remains a reliable criterion of the profound metabolic conditions, and that argumentative methods must be used in its quantification.
The aim of this prospective clinical study was to analyze graft-enhanced soft tissue healing during the initial phases after tooth extraction. Twenty patients in need of tooth extraction (incisors, canines, and premolars) and implant replacement were included. In patients with multiple extractions, one tooth was randomly selected for treatment. After administration of antibiotics, the selected tooth was gently removed. The socket was completely filled with deproteinized bovine bone mineral integrated in a 10% collagen matrix to fill out the space of the alveolus and support the soft tissue. A biopsy punch with a diameter corresponding to the socket orifice was chosen to harvest a free gingival graft of 2- to 3-mm thickness from the palate. The punched graft was carefully sutured to the deepithelialized soft tissue margins of the socket. One week after graft insertion, 64.3% of the mean graft area was fully integrated, 35.6% was fibrinoid, and 0.1% showed necrotic parts. Three and 6 weeks postsurgery, the mean integrated graft surface increased to 92.3% and 99.7%, respectively. After 6 weeks, a mean of 0.3% of the surface in four grafts showed incomplete wound closure, and no fibrin or necrosis was present. Colorimetry of the graft and adjacent tissue revealed a mean color match of deltaE = 2.91, lower than the critical threshold of 3.7 for intraoral visibility of different colors. This soft tissue punch technique led to successful biologic and esthetic integration of the transplanted graft into the local host tissues.
A new method for fast determining the content of amino acid in Cordyceps sinensis by means of near infrared (NIR) spectroscopy was developed. Colorimetry was first employed to measure the actual content of amino acid in Cordyceps sinensis. BP neural network was introduced to model the quantitative correlations between the NIR spectra and the contents of glycine, arginine and total amino acid. By comparing several preprocessing procedures and wavelength ranges, the optimal models could be obtained in the range of 7501.7-6097.8 cm(-1) and 5453.7-4246.5 cm(-1) with first derivative NIR spectra. Standard errors of prediction set (RMSEP) for glycine, arginine and total amino acid were 0.08, 0.07 and 0.36, respectively. The ultimate experimental results indicated that the proposed artificial neural network model was far superior to those of partial least square regression (PLS) and principal component regression (PCR). As an effective nonlinear multivariate calibration strategy, this paper could offer a new approach to the fast measurement of content of chemical components in traditional Chinese medicine by NIR spectroscopy.
The optical properties of skin and of chromophores orientate and absorbe light. The resulting skin colour can be assessed by visual inspection or by objective methods. Spectrophotometry, tristimulus colorimetry and computerized image analysis are well codified methods. Epidermal melanisation is detected with great sensitivity under ultraviolet light illumination.
The establishment of a method of determining minute amount of inulin on nanogram scale is essential for applying micropuncture technique to kidney research. In this experiment, we modified a classical microanthrone method which was used by Dirks et al. to determine inulin contained in tubular fluid. A spectrophotometer was installed with a special microcuvette to suit the colorimetry of 10 microliters solution. Linear relation between inulin concentration and absorption was observed in the range of inulin concentration from 2 to 32 nl per 10 microliters anthrone reagent. The accuracy of this microanthrone method was evaluated with inulin recovery test, the mean recovery rate being 101.2 +/- 3.5%. Since tubular fluid did not interfere with the determination of inulin, the tubular fluid which contained inulin could be added directly to anthrone reagent in actual practice. The mean single nephron glomerular filtration rate measured with this modified microanthrone method in 21 rats was 34.9 +/- 1.8 nl/min, which coincided well with the values reported in literature. The results indicate that the measurement of inulin with the above-mentioned microanthrone method is reliable and suitable for the micropuncture study.
Structural properties of mixed saliva were studied in 30 persons 16-18 years of age divided into 3 groups (10 persons in each) according to different levels of tooth resistance to caries -- 1st with high level of resistance (DMFT=0), 2nd with medium level of resistance (DMFT=4.3+/-0.82), 3rd with low level of resistance (DMFT=6.6+/-0.92). The difference between DMFT figures in groups 2 and 3 was insignificant. In salivary filtrate (collected in the rest conditions and after 5 g sugar load) pH (by potentiometry) and optical density (by photoelectric colorimetry) were determined. 60 saliva samples were collected and 240 determinations were made. In was found that 5 g sugar intake led to structural changes of oral fluid in all groups with different levels of tooth resistance to caries. But in persons with 0 caries incidence the oral fluid micelle resistance and saliva mineralizing capacity were higher than in persons with medium and low resistance to caries. The received data may be used for revelation of oral mineral homeostasis mechanisms and forecasting pathology arising in cases of its disturbance and for planning preventive and curative measures with consideration of their corrections depending upon the level of the individual resistance to caries.
The effect of complexation between cyanidin (extracted from maize seedling roots) and cadmium ions was established in solution on the basis of absorption spectroscopy and colorimetry data. Spectral parameters for identification of the pigment added to the metal has been established.
OBJECTIVE: This study was conducted to obtain the ranking order of a 29-tab (including three "bleaching tabs") Vita Shade Guide for perceived "whiteness" by untrained assessors, and to compare this ranking with both the shade guide manufacturer's rank order and a colorimetrically derived rank order. METHODOLOGY: A total of 85 people, not trained in color assessment by shade guides, were asked to rank order the tabs of a Vitapan 3D Master shade guide for perceived "whiteness" under standardized lighting conditions. A whiteness ranking was also obtained colorimetrically using a Minolta CM-2600d spectrophotometer calibrated to give CIE whiteness values. The data were analysed using means, standard deviations, and standard errors. RESULTS: The assessors varied more in their rankings for darker shades than the lighter ones. The order derived by the assessors and the colorimetry order did not match well with the manufacturer's order, especially toward the darker shades. CONCLUSION: For use in studies of whitening products, a new order of the Vitapan 3D Master shade guide tabs has been developed in relation to whiteness.
Previous studies have demonstrated the suitability of image analysis of tetrazolium-stained colonies to assess growth and drug sensitivity of human tumor cells cultivated in soft agar culture. In the present study, the potential utility of colorimetric analysis to expedite experimental drug evaluations using human tumor cell lines was investigated. The same culture dishes were assessed by image analysis and by formazan colorimetry for purposes of comparing multiple methods of measuring growth as well as growth inhibition. Replicate cultures treated with 2-(p-iodonitrophenyl)-3-p-nitrophenyl-5-phenyltetrazolium chloride or 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide exhibited nearly identical colony count and volume indices as well as excellent correlation in colorimetric end points. Colony-forming unit volume analysis versus colorimetric assessment of the same cultures following dimethyl sulfoxide extraction of protamine sulfate-rinsed, dried soft agar cultures exhibited excellent linear correlation for both growth (Pearson r ranging from 0.95 to 1.00) and drug sensitivity (Pearson r ranging from 0.90 to 0.99, and Spearman r ranging from 0.82 to 0.97) and similar drug sensitivity profiles. Results of the current investigation indicate that end points of soft agar culture remain stable for a period of at least 2 weeks following assay termination. In addition, a colorimetric detection range of 1.3-2.2 log units permits determinations of survival levels ranging from 100 to 5% of respective control levels. Colorimetric analysis is anticipated to expedite soft agar colony formation assay evaluations (a) by reducing the need to use the more rigorous and time-consuming image analysis procedures to measure activity in preliminary drug sensitivity assays and (b) by permitting the determination of effective concentration ranges of new experimental agents for subsequent, more detailed investigations.
OBJECTIVE: To detect the polysaccharides content of tissue culturing seedlings on Dendrobium candidium under special sound wave stimulation. METHODS: The content of polysaccharides was detected by phenol-vitriol colorimetry method. RESULTS: The polysaccharides content of the groups stimulated continuously for 24d was higher obviously than the content of the control groups. CONCLUSION: The stimulation of the special sound wave promoted markedly the synthesis of polysaccharides in D. candidium. It may affect obviously the metabolic pathway of polysaccharides in D. candidium.
The objective of this multidisciplinary clinical investigation was to test whether amocarzine was absorbed effectively and safely in patients of two races and either sex infected with Onchocerca volvulus while living in the holoendemic area of Esmeraldas Province, Ecuador. The prerequisite for a systemic onchocercacidal effect is the regular absorption of orally administered amocarzine. Single dosing after overnight fasting proved to produce irregular absorption of amocarzine, although some microfilaricidal effect was achieved. A pilot study with repeated low dose and postprandial administration of amocarzine showed a regular and predictable absorption with acceptable tolerability and a microfilaricidal effect lasting up to one year post-therapy. Since amocarzine and its major N-oxide metabolite are coloured agents, urine colorimetry was used to assess the urinary excretion of the N-oxide qualitatively. For the postprandial drug regimens plasma concentrations of amocarzine and its metabolite were determined at two selected time points in patients of two races and either sex; the results showed no major differences. Excision of onchocercal nodules was performed four months post-therapy. The pooled results of the histologic analysis of 100 patients with the same drug regimen read under blinded condition showed that 65% of the adult female worms were dead, 20% necrobiotic and 15% alive. The male worms were fewer and mainly necrobiotic. Control worm populations in Esmeraldas without chemotherapy showed that on the average 81.5% were alive and 18.5% dead. Amocarzine was also microfilaricidal producing a reduction of skin dwelling microfilariae to about 10% of the initial value within the first week after start of therapy and lasting for half a year at a 20% level. The reduction of ocular microfilarial was slower and reached 35-40% after one year. The general tolerability was acceptable to good. Reversible dermal reactions were usually mild and peaked as a rash in 57% of the patients on day 6. No prohibitive ocular intolerance was observed. Mild and reversible dizziness peaked on day 4 in 74% of patients. A positive reversible Romberg sign was found in 12 patients on day 4. Amocarzine, the first oral micro- and macrofilaricidal agent administered as a low dose repeat regimen (3 mg/kg twice daily and postprandial for three consecutive days) can be recommended for oral onchocercacidal therapy in adult patients. Clinical trials in juveniles should be encouraged.
A study of the chemical changes of phospholipid in crude and fried semen Dolichos Lablab was carried out by molybdenum blue colorimetry and TLC scanning. The result shows that both the total phospholipid contents and the molar fraction of phosphatidylcholine in the fried samples are decreased as compared with the crude ones.
The determination of calcium, phosphorus, and magnesium in cheese was collaboratively studied. The sample is dried and ashed and the residue is dissolved in an acidified aqueous solution. Calcium and magnesium are determined by atomic absorption spectrophotometry and phosphorus is determined by colorimetry. The study was repeated 3 times because of high within- and between-laboratory relative standard deviations (RSDr and RSDR, respectively). Poor precision in the first 2 studies was caused by a number of factors, including use of contaminated glassware, improperly maintained instruments, and impure reagents as standards. In each study, 5 varieties of cheese were distributed as 10 blind duplicate samples along with a practice sample. Thirteen laboratories participated in the third study, which was generally problem-free. The range of results and the average RSDr and RSDR found in the cheeses were: calcium, 608-1107 mg/100 g. 1.5%, 2.6%; magnesium, 23.9-50.6 mg/100 g, 2.8%, 3.8%; phosphorus, 444-695 mg/100 g, 1.2%, 1.6%. The method has been adopted official first action by AOAC.
The contents of histamine in processed Phytolacca americana has been determined by colorimetry. The result shows that the contents tend to decrease by 23.3% when the herb is shredded, but get a bit higher again when fried with vinegar. The method may be useful in the quality control of the herb.
Using the enzymes terminal deoxyribonucleotidyltransferase (EC 2.7.7.31) and polynucleotide phosphorylase (EC 2.7.7.8), we constructed polyriboadenylic acid tracts, approximately 8000 AMP residues long, attached to the 3'-terminus of a synthetic deoxynucleotide. The polyadenylated DNA, termed the "signal strand", was used in a displacement-type nucleic acid probe assay (see pp 1631-6, this issue). A probe-signal strand complex was made by hybridizing the signal strand to a deoxycytidylate-terminal probe DNA. The probe-signal strand complex was immobilized on an oligo (dG)-cellulose support and subsequently displaced from the immobilized hybrid complex with various amounts of analyte DNA. After the displacement procedure, the polyadenylate tracts were converted to ATP by the combined action of polynucleotide phosphorylase and pyruvate kinase. ATP was quantified by a bioluminescence assay with luciferase from Photinus pyralis. Displacement events were also quantified with biotinylated signal strand bound to avidin-conjugated horseradish peroxidase. Such enzyme-amplified assays offer considerable versatility: they may be coupled to a variety of detection systems including colorimetry, fluorimetry, and luminometry.
This method for the rapid colorimetry of cyanide in blood, applicable to patients exposed to toxic levels of cyanide, is based on the König reaction, which produces a chromophore from cyanide as well as thiocyanate. The latter compound, normally present in blood, is confined to plasma. Thus, its interference with determination of cyanide was eliminated by performing the assay on the erythrocytes, which contain most of the blood cyanide. Furthermore, cyanide was trapped in the erythrocytes and stabilized during the initial washing steps by conversion of hemoglobin to methemoglobin with inorganic nitrite.
Chemiluminescence analysis, with flow injection, is used for the determination of vitamin B12 by means of the luminol hydrogen peroxide system. The linear range is 3 orders of magnitude and the detection limits is 10 ppb. All samples were analyzed by both this method and colorimetry and some comparison between these two methods was made as well. Because of its sensitivity, it can be used as a convenient, and rapid method for clinical drug analysis.