Colorimetry ; Humans ; Technology, Dental ; methods

Colorimetry ; methods ; Humans ; Manganese ; urine ; Potassium Permanganate

OBJECTIVETo develop a new color matching method in dentistry by application of digital photography.

METHODSDigital photographs were obtained of Vitapan 3D-Master shade guide and natural teeth under the same condition, the L*a*b* values of each digital photography were assessed and analyzed by Photoshop CS4.

RESULTSThe Vitapan 3D-Master shade guide was divided into 5 groups, the L* values were similar in each group, but decreased from group 1 to 5. The a* values of L1.5 and L2.5 were minimum, R1.5 and R2.5 were maximum and M1-M3 were intermediate. Compared with Vitapan 3D-Master shade guide, the L*a*b* values of natural teeth were higher.

CONCLUSIONDigital photography can basically reflect the color of Vitapan 3D-Master shade guide, and provides a reference for color matching in dentistry.

Adult ; Color ; Colorimetry ; methods ; Humans ; Photography, Dental ; methods ; Prosthesis Coloring

The cytotoxicity of medical ultrasonic couplant was tested by MTT assay and agar overlay test. By MTT assay, when the inoculum density was high, the cytotoxicity level was low, or vice versa. The cytotoxicity grade tested by agar overlay was not accord to MTT assay's too. MTT assay is suitable to test the cytotoxicity of medical ultrasonic couplant because it is quantitative and more sensitive, however, the experimental condition and the preparative method of extraction should be determined.
Animals ; Cell Line ; Colorimetry ; Cytotoxicity Tests, Immunologic ; methods ; Mice ; Ultrasonics

The biochemical analysis of urine is an important inspection and diagnosis method in hospitals. The conventional method of urine analysis covers mainly colorimetric visual appraisement and automation detection, in which the colorimetric visual appraisement technique has been superseded basically, and the automation detection method is adopted in hospital; moreover, the price of urine biochemical analyzer on market is around twenty thousand RMB yuan (Y), which is hard to enter into ordinary families. It is known that computer vision system is not subject to the physiological and psychological influence of person, its appraisement standard is objective and steady. Therefore, according to the color theory, we have established a computer vision system, which can carry through collection, management, display, and appraisement of color difference between the color of standard threshold value and the color of urine test paper after reaction with urine liquid, and then the level of an illness can be judged accurately. In this paper, we introduce the Urine Test Biochemical Analysis method, which is new and can be popularized in families. Experimental result shows that this test method is easy-to-use and cost-effective. It can realize the monitoring of a whole course and can find extensive applications.
Automation ; Colorimetry ; methods ; Diagnosis, Computer-Assisted ; Humans ; Signal Processing, Computer-Assisted ; Urinalysis ; methods

BACKGROUND: The ammonia contained in tobacco fillers and mainstream and sidestream cigarette smoke accelerates nicotine dependence in cigarette smokers. Ammonia has been included in the non-exhaustive priority list of 39 tobacco components and emissions of cigarette published by the World Health Organization (WHO) Study Group on Tobacco Product Regulation. The development of a simple ammonia detection method will contribute to the establishment of tobacco product regulation under tobacco control policies and allow surveys to be conducted, even by laboratories with small research budgets. METHODS: We developed a simple colorimetric method based on the salicylate-chlorine reaction and absorption spectrometry with two reagents (sodium nitroprusside and sodium dichloroisocyanurate). To compare this method to conventional ion chromatography, we analyzed the ammonia levels in tobacco fillers extracted from 35 Japanese commercially marketed cigarette brands manufactured by four tobacco companies (Japan Tobacco (JT) Inc., British American Tobacco (BAT), Philip Morris Japan, and Natural American Spirit). We also analyzed the ammonia levels in the sidestream smoke from cigarettes of the brands that were found to contain high or low tobacco filler ammonia levels. RESULTS: The ammonia levels in the reference cigarette (3R4F) measured by our method and ion chromatography were similar and comparable to previously reported levels. The ammonia levels in tobacco fillers extracted from 35 cigarette brands ranged from 0.25 to 1.58 mg/g. The mean ammonia level of JT cigarette brands was significantly higher (0.83 ± 0.28 mg/g) than that of Natural American Spirit cigarette brands (0.30 ± 0.08 mg/g) and lower than those in the other two cigarette brands (1.11 ± 0.19 mg/g for BAT and 1.24 ± 0.15 mg/g for Philip Morris) (p < 0.001 by Bonferroni test). The ammonia levels in the sidestream smoke of CABIN, Marlboro Black Menthol, American Spirit Light, and Seven Stars were 5.89 ± 0.28, 5.23 ± 0.12, 6.92 ± 0.56, and 4.14 ± 0.19 mg/cigarette, respectively. The ammonia levels were higher in sidestream smoke than in tobacco filler. CONCLUSIONS Our simple colorimetric could be used to analyze ammonia in tobacco fillers and sidestream smoke. There were significant differences between the ammonia levels of the 35 commercially marketed cigarette brands in Japan manufactured by four tobacco manufacturers. Over 90% of the ammonia in sidestream smoke was in gaseous phase.
Ammonia ; analysis ; Colorimetry ; methods ; Japan ; Smoke ; analysis ; Spectrophotometry ; methods ; Tobacco ; chemistry ; Tobacco Products ; analysis

OBJECTIVETo analyze the limitation of currently used shade guide systems comparing with color range of nature teeth.

METHODSDigital pictures of shade guide systems A (VITAPAN Classic), B (VINTAGE Halo), C (3D-MASTER), and 322 central incisors were taken under the same condition as light source of D65 with the observation method of d/0 degrees. The data obtained from nature tooth color were compared with the color range of three shade guide systems mentioned above in items of L * a * b */C * H degrees.

RESULTSThe normal chroma value (95%) of the natural teeth were L* 61.631-73.250, a * -0.719-1.879, and b * 8.701-17.790. Natural tooth colors were different from those of the shade guide system A which color range was narrower, short of red hue, higher values, and unevenly distribution of saturation. On the other hand, the range of red hue increased in shade guide system B while its saturation was slightly high. The color range of shade guide system C was greatest among the three shade guide systems. The saturation and value of shade guide system C covered all varieties of nature teeth measured in this research, but it still lacked red hue comparing to the nature teeth.

CONCLUSIONSComparing the color range of nature teeth, the shade guide systems used in clinic have uneven hue distribution and cannot cover all colors of nature teeth. Generally, all the shade guide systems are lack of the hues which are named under the category of red tone.

Adult ; Colorimetry ; methods ; Dental Prosthesis Design ; Female ; Humans ; Incisor ; Male ; Prosthesis Coloring ; Young Adult

A simplified colorimetric method for measurement of the levels of glycosylation of proteins was developed by a modification of an existing method. Employing this method, the extent of nonenzymatic glycosylation of apolipoprotein B subspecies(B-100, B-74, B-26), LDL, VLDL and total serum proteins in human plasma obtained from patients with diabetes mellitus and control subjects was compared. Plasma LDL (1.019 < d < 1.063) and VLDL(d < 1.006) were separated using the sequential ultracentrifugation method, and the subspecies of apolipoprotein B were isolated by extracting them from polyacrylamide gels after they were separated by preparative SDS-polyacrylamide gel electrophoresis. Increases in the level of glycosylation of serum proteins, LDL, VLDL, and apo B subspecies obtained from diabetic patients were observed. Among them, the increases of glycosylated LDL and apo B-26 were most significant (p < .001). Also, good correlations were found between glycosylations of apo B-26 and LDL (r=.88), and glycosylation of LDL and LDL cholesterol level(r=.79). The results also showed an excellent correlation between levels of HbA1c and glycosylated apo B-26(r=.93).
Adult ; Colorimetry/methods* ; Diabetes Mellitus, Non-Insulin-Dependent/blood* ; Glycosylation ; Human ; Lipoproteins, LDL/blood*

Bacterial Infections ; diagnosis ; urine ; Colorimetry ; Female ; Humans ; Male ; Middle Aged ; Peritonitis ; diagnosis ; urine ; Urinalysis ; methods

OBJECTIVETo prepare the low molecular weight chitosan (LMWC) and establish the method for quality control.

METHODUse enzymatic degradation to prepare LMWC with chitosan, and separate by ultrafiltration; the molecular weight and purity were determined by gel permeation chromatography (GPC) and colorimetry respectively.

RESULTLMWC was prepared by control the hours of enzymatic degradation and ultrafiltered through filter with cutoff molecular of 10K Dalton and 50 K dalton; the average molecular weight was 20 K dalton and the purity was (96.60 +/- 1.56)%.

CONCLUSIONThe condition of enzymatic degradation is geniality and easy to control, LMWCs with different molecular weight can separate by ultrafiltration efficiently; the quality of LMWC can control with gel permeation chromatography (GPC) and colorimetry.

Cellulase ; metabolism ; Chitosan ; chemistry ; Chromatography, Gel ; Colorimetry ; Hydrolysis ; Molecular Weight ; Quality Control ; Technology, Pharmaceutical ; methods