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PubMed1983

Formaldehyde-induced fluorescence method for touch preparations from amelanotic melanoma tissues: a simple and rapid method for the demonstration of melanogenic activities of amelanotic melanoma cells.

Touch preparations from four amelanotic melanoma tissue samples were studied with the formaldehyde-induced fluorescence method. Fluorescent amelanotic melanoma cells could easily be detected under a fluorescence microscope. The fluorescence microscopic pictures obtained by the touch-fluorescence method were equally evaluated with those obtained by the classical fluorescence method. The method made it possible to demonstrate the melanogenic activity of amelanotic melanoma cells within 30 min. The routine application of this method to the diagnosis of amelanotic melanoma is suggested.

Fluorescence↗

PubMed1983

Comparative studies on different methods in typing strains of erysipelothrix rhusiopathiae. II. Comments on the methods and type classification tests of E. rhusiopathiae strains.

The tube precipitation method with antigen produced from autoclaved organisms and those produced by CH3COOH extraction and with good antisera have proved to give the best results and should be preferred at least in the routine work. It is a quick method but the results cannot be fixed and later used in documentation. - The paper chromatographic method is very sensitive, makes much work and heavy demands on the clarity of the antigen and serum and reading the test. The results can be fixed and used in documentation. The agar gel diffusion method demands more work than the other methods but the preparation can be stained and stored, the precipitation lines can reveal differences in antigenic structure of different strains. Erysipelas strains world-wide known as standard strains of the individual types have been examined. Some changes in the type classification are recommended. Signs of antigen differences of strains of the same type and mutual antigens in strains of different types can be detected in the results.

Animals↗

PubMed1984

Methods in laboratory investigation. Immunoelectron microscopic methods for demonstration of antigens on normal human melanocytes and other epidermal cells.

Different procedures for fixation and processing were evaluated in order to examine the antigenic profile of melanocytes and other epidermal cells for immunoelectron microscopy. For this purpose the monoclonal antibodies anti-HLA-A, B, C, anti-HLA-DR, anti-T6, and the melanoma-associated monoclonal antibody NKI /C-3 were used as markers. Fixation with periodate-lysine-paraformaldehyde yielded better antigenic and ultrastructural preservation than 3% paraformaldehyde or picric acid-paraformaldehyde did. Skin was further processed by five different methods: (a) 15-micron frozen sections; (b) 75-micron agar-embedded, tissue chopper sections; (c) 15-micron polyethylene glycol-embedded sections; (d) epidermal cells in suspension; and (e) epoxy sections (postembedding staining) were prepared for the immunoperoxidase procedure. Antigenicity was best preserved in the cell suspension method and somewhat less, but with a similar staining distribution, with the first three methods. Staining with the polyethylene glycol-embedded sections was only achieved if they were left free-floating in buffer; no staining was observed when the sections were mounted on glass slides and left to dry overnight at 37 degrees C. Epidermal cells remained unreactive in the postembedding method, even after etching. Ultrastructural preservation of the agar-embedded sections and the cells in suspension was superior to the other preembedding methods. Melanocytes mostly showed moderate staining for HLA-A, B, C and slight staining for the antigen that is recognized by NKI /C-3. The latter was further demonstrated on Langerhans cells and indeterminate cells which also expressed HLA-A, B, C, T6, and HLA-DR antigens.

Antibodies, Monoclonal↗

PubMedDate not supplied

[Method of conformational calculations of large fragments of nucleic acids. IV. Comparative calculations of dinucleotides by the fragment and atom-atom methods].

Calculations of properties of the dinucleotides for the estimation of the accuracy of our method of group-group interactions for conformational calculations of large polynucleotide fragments were performed. Values of the torsional angles for the close and open conformational states which were found by our method differ by no more than 10 degrees from the conformations which were found by the method of atom-atom interactions. Accuracy of the conformational energy calculations by the group-group method was about 0.5-1.5 kcal/mol for close and open conformation states, respectively. The acceleration factor for conformational properties calculations by our group-group interactions method was about (100 N + 14)/(N + 20), where N is the number of monomers in the chain.

Dinucleoside Phosphates↗

PubMed1984

Clinical evaluation of a fully automated chromogenic method for prothrombin time compared with a conventional coagulation method.

The clinical usefulness of a chromogenic method for prothrombin time (PT) determination has been assessed in a wide range of clinical conditions, and it is compared with the conventional clotting method for PT. The new method appears to be as sensitive as the clotting PT to deficiencies of clotting factors of the extrinsic and common pathway, except for fibrinogen. Patients with proven liver disease were correctly diagnosed with a prevalence of abnormal results comparable to that by the clotting PT. Results by the two methods correlated highly (r = 0.96) for normal and congenitally deficient plasmas as well as for plasmas from patients on oral anticoagulant treatment (r = 0.95). High reproducibility (between-assay CV less than 3%) and easy adaptation to centrifugal analyzers make it a suitable candidate to replace the conventional method.

Adolescent↗

PubMed1981

[Quantitative estimation of potentiating or inhibitory effects of similarly acting drugs in combination. Advantages of a dose-response curve method over the isoboles-method (author's transl)].

Experimental effects of two synergistically acting drugs in combination can be compared with theoretical additive effects by means of various methods. In this paper a new method has been extended and analyzed for its advantages over the isoboles method. The main advantages of the new method are the simplicity of the experimental technique of combination-experiments, the evaluation in terms of dose-response curves and the adequate quantitative determination of non-additive combination effects. The method allows the evaluation of the mode of action of effects brought about in combination, e.g., in functional and sequential potentiation.

Dose-Response Relationship, Drug↗

PubMed1981

Automated Jendrassik-Grof method for measurement of bilirubin in serum with the Greiner Selective Analyzer (GSA II D), and comparison with the method involving diazotized 2,4-dichloroaniline.

We automated the Jendrassik-Grof method for measurement of bilirubin with the Greiner Selective Analyzer GSA II D. Comparison with the manual Jendrassik-Grof method showed a highly significant correlation coefficient of 0.994 for total and 0.980 for "direct" bilirubin measurement. The automated method showed good precision and was linear to 667 mu mol/L, the highest concentration tested. Addition of hemolysate caused a greater effect on the measurement of direct bilirubin than on total bilirubin. The inhibitory effect on measurement of total bilirubin, though small, was statistically significant at hemoglobin concentrations greater than 2 g/L. Comparison with the method involving diazotized 2,4-dichloroaniline showed the Jendrassik-Grof method to be relatively less affected by hemolysis and turbidity in the measurement of total bilirubin.

Autoanalysis↗

PubMedDate not supplied

Delay method of implantation enhances implant-bone binding: a comparison with the conventional method.

This report compares the conventional and delay methods of implantation, evaluating the bone formation around a dense apatite implant. In the conventional method, the implant is placed immediately after the cavity is prepared. In the delay technique, the implant is placed 2 weeks after preparation. This study found that many new thin trabeculae and capillaries formed around the cavity during the delay period, while none had formed at the time of implantation using the conventional method. The delay method showed earlier and wider bone formation, and less surrounding fibrous encapsulation. These results indicate that the delay technique can be an efficient method for establishing good bone binding.

Animals↗

PubMedDate not supplied

Comparison of Chemstrip bG visual blood glucose method with Accu-Chek III monitor method for measuring blood glucose in broiler chicks.

The purposes of this study were to 1) measure blood glucose values in a flock of broiler chicks tentatively diagnosed as having spiking mortality syndrome (SMS), and 2) compare the blood glucose values using two methods: the Chemstrip bG visual method and the Chemstrip bG Accu-Chek III monitor method. Results indicated that Chemstrip bG reagent test strips can be used successfully to assay blood glucose values in chicks with SMS and that these strips will detect hypoglycemia when hypoglycemia is present. Readings obtained by the visual method were as reliable as those obtained by the more expensive and time-consuming digital electronic monitor method. Blood glucose values were lowest in the chicks with the most severe clinical signs. Malassimilation is a differential diagnosis for hypoglycemia among neonatal mammals, and blood glucose values are lower in inappetent or starving chicks. Therefore, the hypothesis that gastrointestinal or endocrine disease could be major etiologies of hypoglycemia and spiking mortality should be investigated.

Animals↗

PubMed1993

[Clinical assessment of serum intestine type alkaline phosphatase using Japan Society of Clinical Chemistry (JSCC) recommended method--assessment of JSCC recommended method followed by indoxylphosphate staining].

We assessed a clinical usefulness of JSCC (Japan Society of Clinical Chemistry) recommended method for the measurement of serum alkaline phosphatase. The recommended method is completely correlated both in the liver-bone and intestine isoenzymes with Kind-King method recommended by the expert panel of liver function tests in Japanese Society of Gastroenterology. On the other hand, mixed tests of liver-bone and intestine isoenzyme completely show the full recovery at any combinations of both enzymes using indoxylphosphate isoenzyme staining method. These results indicated that the quantitative analysis of blood alkaline phosphatase is possible employing the combination of JSCC recommended and indoxylphosphate staining methods. Employing these combinations, we could effectively assess the pathophysiological significance of intestine alkaline phosphatase appeared in liver cirrhosis and portal hypertension.

Alkaline Phosphatase↗

PubMed1995

Polyethylene glycol method is superior to ammonium sulfate and protein-A sepharose-4B method in fractionating thyroid stimulating immunoglobulin in Graves' disease.

BACKGROUND: The purpose of this study is to compare the performance of three methods, i.e., ammonium sulfate, polyethylene glycol (PEG) and protein A sepharose 4B in fractionation of thyroid stimulating immunoglobulin. METHODS: Twelve patients with Graves' disease and twelve age-, sex-matched normal controls were recruited. 0.9 ml of saturated ammonium sulfate was added slowly to 1.1 ml of sera of all subjects and was stirred until reaching 45% saturation. The precipitation was allowed to form at 4 degrees C overnight. The solution was centrifuged at 10,000 x g for 5 minutes. The precipitate was washed twice with 45% ammonium sulfate, dissolved in 0.55 ml of distilled water equal to half of the initial volume of the serum and dialyzed against 200 volumes of phosphate-buffered saline (PBS) for 48 hours. Another 0.5 ml of serum sample from the same patients was mixed with 1.5 ml of 20% polyethylene, followed by centrifugation at 2,800 g for 20 minutes. The pellet was dissolved in 0.6 ml of Hanks' medium without NaCl containing 1.5% bovine serum albumin, 20mM HEPES: 1 ml of sera was applied to 0.75 g of protein A sepharose-4B in PBS buffer and eluted with glycine, pH 2.3. By adding immunoglobulin (Ig) from the different methods to the FRTL-5 tissue culture, we determined the cAMP generation. RESULTS: Patients with Graves' disease were found to have higher serum thyroxine and triiodothyronine concentrations (p < 0.001) and significantly higher free thyroxine concentration than normal subjects. Ig elicited stronger response in cyclic AMP generation when prepared with PEG method, as compared with the other two methods (p < 0.001). With sepharose-4B Ig preparation, 10 out 12 patients (83.33%) showed positive thyroid stimulating immunoglobulin (TSI) while with ammonium sulfate precipitation, nine out 12 patients (75%) showed positive TSI. On the other hand, all patients showed positive TSI with PEG precipitation. When the degree of thyrotoxicosis was classified in terms of thyroid hormone concentrations, there was no correlation between TSI titers and thyroid hormone concentration. CONCLUSIONS: Polyethylene glycol is superior to both ammonium sulfate and protein A sepharose-4B in fractionating TSI in terms of sensitivity and convenience in operation.

Adult↗

PubMed1993

Genetico-mathematical analysis of the inheritance pattern of peptic ulcer disease. II. Method of simple registration. Assessment of the direct methods of Weinberg.

The inheritance pattern of ulcer disease was analyzed by means of the method of simple registration. We also studied comparatively and assessed all direct methods of Weinberg using the coefficients of genetic proportion calculated by them as a criterion at complete inclusion of the investigated groups. 351 probands' families were studied: 57 with type II and 27 with type III gastric ulcer disease and 267 with duodenal ulcer disease. Gastric ulcer types were determined according to the classification of H. Johnson. The coefficient of genetic proportion in the cases of duodenal ulcer disease was additionally calculated according to the type of patients' familial pre-disposition. The coefficient of genetic proportion was found to acquire identical values for all groups studied without exception when calculated on the basis of one proband in a family (y = 1) both by the method of probands and the method of simple registration. The segregation coefficient values obtained using the direct methods of Weinberg do not support the hypothesis of monogenic transmission pattern either of the ulcer disease as a whole or of its different varieties.

Female↗

PubMed1994

[Trichinellosis in slaughtered and wild animals in Switzerland using a digestion method and a serologic method (E/S-ELISA)].

For many decades trichinellosis has not been reported among Swiss domestic pigs. Considering the fact that Trichinella occurs in a sylvatic cycle in Switzerland, a study was designed to reevaluate the present epidemiologic situation by investigating 10,904 fattening pigs, 218 pigs with free access to pasturage or being kept on an alp, 104 domestic boars, 106 horses, 44 wild boars and 538 foxes using a direct and an indirect diagnostic technique (digestion method and serology with ELISA and an excretory/secretory antigen, respectively). The digestion method was performed according to EC-guidelines. Furthermore, 25,239 sera originating from a Swiss sow-serum bank were tested retrospectively for anti-Trichinella antibodies. Trichinella was not detectable in all domestic pigs using the digestion method. Serologically, 3 fattening pigs (0.027%) and 9 sows (0.036%) demonstrated weak antibody reactivities against the Trichinella E/S-antigen. Based upon statistical calculations for the negative-positive threshold, these antibody-reactions were considered to be within the normal range of variability of the test. Although statistically restricted, the results of the present study indicate the absence of Trichinella within the Swiss pig population. Based upon the rational applicability of the ELISA and its diagnostic sensitivity and specificity, this test appears as the most suitable method to perform large-scale screenings among slaughter pigs. Pigs with free access to pasturage and boars were all parasitologically and serologically negative for Trichinella. The digestion method showed that horses and wild boars were all parasitologically negative, whereas 1.3% of the foxes were positive for Trichinella larvae.

Abattoirs↗

PubMed1993

[A basic study on a highly sensitive automated method for hypercoagulable state in plasma, fluorogenic prothrombin time (FPT) method].

A highly sensitive automated method, fluorogenic prothrombin time (FPT) method, was developed by a combination of a fluorogenic peptide substrate for thrombin and a centrifugal autoanalyzer (Cobas Bio). Using plasmas from stroke patients, we showed that the second reagent containing fluorogenic peptide substrate should be mixed after the first reagent containing tissue factor and plasma were mixed, that is, two steps method, in order to detect hypercoagulable state. When the first and the second reagent were mixed with plasma at the same time, that is, one step method, FPT was not sensitive to hypercoagulable state. We also showed that patient plasmas should be stored at -80 degrees C and subjected to FPT analysis immediately after thawing, not leaving at 4 degrees C or room temperature. Good correlation was observed on FPT of stroke patients using human tissue factor and bovine tissue factor. Another fluorogenic method was developed by the same principle for the evaluation of factors X and VII concentrations in plasma using deficient plasma of factor X or factor VII. Good correlation was observed on factors X and VII concentrations of stroke patients using human tissue factor and bovine tissue factor.

Blood Coagulation Tests↗

PubMed1993

A method for the preparation of DNA from calf thymus nuclei in maximum purity and yield, analysis of this DNA compared with that obtained by other methods.

In the preparation of calf thymus DNA, a method (1) was developed to yield DNA in maximum yield and purity, with a minimum of shear degradation, which differed in three respects from those used in standard preparations: 1) use of calf thymus nuclei rather than whole tissue as a source of the DNA; 2) use of initial Pronase, then on the next cycle RNAase + Pronase digestions; 3) use of optimal concentrations of reagents to precipitate denatured proteins in the purification cycles. The optimal reagent concentrations were determined in tests by changing each variable one at a time to be 3M NaCl, 3% sarcosyl. The purification cycles consisted of adjustment of DNA solution in buffer to 3M NaCl-3% sarcosyl, centrifugation, alcohol precipitation, and redissolving DNA fibers in buffer. The DNA from nuclei, digested with Pronase then with RNAase + Pronase was then subjected to five additional purification cycles. The purified DNA thus obtained (N-DNA) had a protein content of 0.64%. When purified calf thymus nuclei are subjected directly to salt-sarcosyl purification cycles, the initial protein content is about 21%, but after the second cycle the percentages of protein fell off in subsequent cycles in a parallel manner as compared to the DNA obtained by the Blin and Stafford method (2) and then subjected to NaCl-sarcosyl purification. The degree of purity obtained by these purification methods was appreciably greater than obtained for a modified method of Gross-Bellard et al. (3). Two portions of DNA purified by this method were analyzed: 1) dialyzed 11 times after the Proteinase K digestion, and 2) dialyzed 6 times. Portion 1) gave a protein content of 0.96% and a yield of 0.135% (g/100 g tissue). Portion 2) gave a protein content of 1.34% and a yield of 0.133%.

Animals↗

PubMed1993

Candidate reference methods for determining target values for cholesterol, creatinine, uric acid, and glucose in external quality assessment and internal accuracy control. II. Method transfer.

We describe the testing of transferability of candidate Reference Methods developed by INSTAND for cholesterol, creatinine, uric acid, and glucose. The methods are based on isotope dilution-gas chromatography--mass spectrometry. The study consisted of two parts: setup of the methods and self-evaluation for readiness in the collaborating laboratory, followed by independent measurements in parallel with INSTAND. Criteria used for judging the transferability and general reliability of the candidate Reference Methods were: the accuracy and precision of the collaborating laboratory and the agreement between the two laboratories. The accuracy was judged from the results on the Standard Reference Material 909 from the National Institute of Standards and Technology. For all analytes except glucose the bias from the certified value was < 0.7%. The mean intralaboratory imprecision ranged from 0.66% to 1.24%. The agreement between the results was tested by an advanced linear-regression analysis and Student's t-test. In general, the results demonstrate that the candidate Reference Methods developed by INSTAND can be successfully transferred without loss of their inherent precision and accuracy.

Blood Glucose↗

PubMed1996

[A quantitative study of regional cerebral blood flow in patients with dementia of Alzheimer type using single photon emission computed tomography--clinical application of the IMP autoradiographic method (IMP ARG method)].

We quantitatively measured regional cerebral blood flow (rCBF) in 37 patients with dementia of Alzheimer type (DAT) to investigate the clinical utilities of the N-isopropyl-p-[123I]iodoamphetamine autoradiographic method (IMP ARG method) that is a quantitative method more simplified and less invasive for IMP-SPECT developed by Iida et al. A given standard input function and a given value of distribution volume (Vd) used for the rCBF measurement of this method were calculated from the dynamic study by six normal volunteers. Mean values [SD] of rCBF (ml/ 100 g/min) in the Cerebral Cortex were 49.0 [6.0] in the controls (n = 20), 42.6 [5.9] in mild DAT group (n = 14), 36.7 [5.5] in moderate DAT group (n = 12), and 26.4 [7.5] in severe DAT group (n = 11), respectively. These values were significantly different between each neighboring group. Moreover, the correlations between the score by the Hasegawa dementia scale (HDS-R) and each rCBF were significant in the temporal, parietal, and frontal cortex. These findings suggest that the rCBF measurement in IMP-SPECT using this method is useful for the diagnosis of the clinical severity in patients with DAT.

Aged↗

PubMed1977

[Assessment of bacterial counts in the meat-processing industry. III. The Stomacher method and the spiral plate method].

Two aids in the assessment of bacterial counts were evaluated. The Colworth-Stomacher technique is a reliable alternative to the relatively more expensive and more labour-intensive blendor method of homogenizing meat. In the suspensions obtained by the two methods, equally high bacterial counts were observed. The Spiral plate method provides equally high numbers of bacteria as does the pour-plate method, and reproducibility of the results is identical. In counting the total number of aerobic bacteria, the two methods show a very high correlation: r = 0.99.

Animals↗