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Association between the accessibility to lethal methods and method-specific suicide rates: An ecological study in Taiwan.

OBJECTIVE: To examine the association between availability of lethal methods of suicide and method-specific suicide rates at the city/ county level in Taiwan. METHOD: Age-adjusted and age-specific suicide rates of 23 cities/counties in Taiwan for the years 1999 to 2003 were calculated. Partial correlation coefficients were used to examine cross-sectional associations between independent variables, i.e., proportion of agricultural population and proportion of households living on the sixth floor or above, and suicide rates by different methods (poisoning by solids/liquids, jumping, and hanging) after adjusting for unemployment rates and prevalence of depression. RESULTS: The partial correlation coefficient was 0.77 (p < .001) for proportion of agricultural population with solids/liquids poisoning suicide rates. It was 0.73 (p < .001) for the proportion of households living on the sixth floor or above with suicide rates by jumping. Correlations between hanging suicide rates and proportion of agricultural population or between hanging suicide rates and proportion of households living on the sixth floor or above were not significant. CONCLUSION: The results showed strong positive associations between access to lethal methods and method-specific suicide rates. Controlling the availability of pesticides and fencing high buildings or installing window guards may be effective measures for suicide prevention.

Adolescent↗

Comparison of the traditional three-tube most probable number method with the Petrifilm, SimPlate, BioSys optical, and Bactometer conductance methods for enumerating Escherichia coli from chicken carcasses and ground beef.

A study was conducted to compare commonly used methods, such as Petrifilm and SimPlate, and the rapid microbiological methods BioSys optical and Bactometer conductance to the standard most probable number (MPN) procedure for enumerating Escherichia coli from poultry carcasses and ground beef. Broiler carcasses and ground beef were evaluated in each of three replicate trials. Five groups of carcasses or ground beef were sampled and analyzed using Petrifilm, SimPlate, BioSys optical, and Bactometer conductance measurements after temperature abuse at 37 degrees C for 0 (Petrifilm and SimPlate only), 2, 4, 6, or 8 h. The correlation coefficients for the regression lines comparing the standard E. coli MPN procedure to Petrifilm and SimPlate for chicken and ground beef, respectively, were as follows: 0.95, 0.94, 0.93, and 0.91. The correlation coefficients for the regression lines comparing the standard E. coli MPN procedure to BioSys optical and Bactometer conductance measurements for chicken and ground beef, respectively, were -0.91, -0.90, -0.93, and -0.96. Although Petrifilm and SimPlate performed well, E. coli could not be enumerated from 16.7 and 10% of samples, respectively, using these methods. The BioSys optical and Bactometer conductance methods performed very well when compared with Petrifilm and SimPlate. Using rapid methods (BioSys optical and Bactometer conductance), results were obtained in 1 to 11 h rather than the 48 h required to conduct Petrifilm or SimPlate or the 5 days required to conduct the MPN procedure. These methods may allow processors to test products and obtain results before shipping, avoiding the cost and loss of reputation associated with a recall or foodborne illness outbreak.

Animals↗

[Development of a simple method for the washout correction of 123I-IMP SPECT and its application to a quantitative rCBF method].

We have developed a simple method to correct the washout of tracer from the brain based on the two-compartment model in brain early SPECT using N-isopropyl-p-[123I]iodoamphetamine (123I-IMP). This correction was applied to a new quantitative method of regional cerebral blood flow (rCBF) in combination with the microsphere method by continuous arterial sampling previously reported. Data acquisition of 123I-IMP early SPECT was started from 35 min after 123I-IMP i.v. injection, and the time activity curve of whole brain on anterior head planar images was monitored immediately after 123I-IMP i.v. injection for the correction of washout of tracer from the brain. The usefulness of this method was evaluated in 12 patients with various brain diseases by comparison with the results obtained from the super-early SPECT at 7-10 min after 123I-IMP i.v. injection. The washout rates in cases of early SPECT corrected by this method ranged from 16.91% to 39.34% with a mean +/- SD of 27.72 +/- 5.44%. The contrast of hypo- to hyperperfusion regions on early SPECT was improved by the correction of the washout, and its intracerebral distribution was similar to the simultaneously obtained super-early SPECT images. These results indicated that the present correction method for the washout was useful for more correct quantification of rCBF.

Brain↗

[Evaluation of two root canal preparation and obturation methods: the Mc Spadden method and the use of ProFile-Thermafil].

BACKGROUND: In endodontic field different instruments and techniques have been suggested for the preparation and filling or radicular bent canals. The purpose of this study is to compare two different cleaning and canal filling methods: preparation and filling technique, according to Mc Spadden's method, instrument technique and the closing of the canal system according to ProFile-Thermafil method. METHODS: In this study ten molars divided into two groups of five elements each were used. The five molars of the first group were prepared according to the "crown-down" technique with nickel-titanium instruments by NT Engine Files Quantec 2000 series. The 18 canals found out in the five molars have been filled with Pac Mac and gutta-percha preheated. The five molars of the second group have 17 radicular canals which, firstly, have been cleaned with ProFile .04 and .06 taper fitted to a manipulator at 220 revolutions per minute and then filled by Thermafil n. 30 with plastic carrier. All ten molars were X-rayed first, during and after the treatment. All teeth were soaked into polymerised resin, dissected into three different points and observed through Optical Microscope. RESULTS: Both cleaning techniques succeed in being efficient in bent canals. The instruments made by Mc Spadden highlight a greater preservation of canal dentine than the ProFile. In samples of the first group there is an excellent adaptation of multiphase gutta-percha to the canal walls and a correct relationship between the filling material and the apical foramen. In filling with Thermafil the adaptation of gutta-percha inside the radicular canal shows outstanding differences in relation to sections taken into account. Actually, while in portion of the crown the filling can be considered satisfactory towards the canal walls, in apical sections there is a decrease in the quantity of gutta-percha step by step, while a contact of plastic carrier with dentine walls is highlighted. CONCLUSIONS: Wheter in the shaping or in the canal filling phase, the two methods are efficient and conservative towards dental structure at the same time. These methods, have an outstanding reduction in dental weakening and in times of the endodontic treatment performance.

Dental Instruments↗

Selection, validation, standardization, and performance of a designated comparison method for HDL-cholesterol for use in the cholesterol reference method laboratory network.

BACKGROUND: Accurate and precise HDL-cholesterol (HDL-C) measurements are essential for effective application of National Cholesterol Education Program treatment guidelines. The Cholesterol Reference Method Laboratory Network (CRMLN) assists manufacturers of in vitro diagnostic products to establish traceability to the accuracy base. CRMLN sought to implement a designated comparison method (DCM) that overcomes the impracticalities of the expensive and labor-intensive reference method for HDL-C. METHODS: CRMLN evaluated candidate DCMs and selected one that uses 50-kDa dextran sulfate with magnesium ions as the precipitation reagent followed by measurement of cholesterol by the CDC reference method. After validating the method, we transferred it to all CRMLN laboratories and successfully standardized it using CDC frozen serum reference materials. CRMLN laboratories participate in monthly performance evaluations. RESULTS: CRMLN laboratories were able to meet a precision goal, as indicated by SD, of </=0.03 mmol/L (1 mg/dL) 94.4% of the time. They were able to meet a bias goal of </=0.05 mmol/L (2 mg/dL) for HDL-C <1.09 mmol/L (42 mg/dL) 97.3% of the time and a goal of </=3% for HDL-C >/=1.09 mmol/L (42 mg/dL) 95.6% of the time. CRMLN is working to further improve its performance by implementing a bias criterion of 0.03 mmol/L (1 mg/dL) for all HDL-C concentrations. CONCLUSIONS: CRMLN selected, validated, standardized, and implemented a DCM for HDL-C that is accurate, robust, transferable, and practical. The DCM is being used to assist manufacturers in calibrating their products so that ultimately, clinical laboratories using the products will more accurately measure HDL-C.

Cholesterol, HDL↗

[Comparison between the standard MPN method recommended by the American Public Health Association and the Simplate and Petrifilm methods for identification of the coliform group and Escherichia coli in tilapia (Oreochromis sp) originating from aquaculture in fresh water].

We have compared three methods for the detection and quantification of coliforms and E. coli in fish: the conventional three-tube MNP method (APHA), the Simplate Method and the Petrifilm Method. Thirty samples of the tilapia's external surface (skin, gills and fin) produced in an artificial pond were collected. Samples were processed individually in buffered peptone water 1%, then they were diluted and inoculated in Simplate, Petrifilm and LST tubes. Coliforms were isolated from 100% of the samples. The Simplate and 3M Petrifilm results were obtained after 24 h of incubation. The conventional three-tube MNP method showed results only after 96 hours of incubation. Simplate showed better recovery of coliforms and E. coli than 3 M Petrifilm and APHA method (P < 0.05). 3M Petrifilm and APHA were not significantly different for E. coli recovery.

Animals↗

The role of lean body mass as a nutritional index in Chinese peritoneal dialysis patients--comparison of creatinine kinetics method and anthropometric method.

OBJECTIVE: To compare, in Chinese continuous ambulatory peritoneal dialysis (CAPD) patients, the creatinine kinetics method (LBM-CK) and the anthropometric method (LBM-AM) for determining lean body mass (LBM). DESIGN: Single-center cross-sectional study. PATIENTS AND METHODS: We studied 151 unselected CAPD patients (78 males, 73 females). We calculated LBM-CK and LBM-AM using standard formulas. The results of the two methods were then compared by the Bland and Altman method. Dialysis adequacy and other nutritional indices, including total Kt/V, weekly creatinine clearance (CCr), residual glomerular filtration rate (GFR), protein nitrogen appearance (PNA), subjective global assessment (SGA), and serum albumin, were measured simultaneously. RESULTS: The mean age of the patients was 55.6 +/- 12.2 years, and the mean duration of dialysis was 33.6 +/- 28.5 months. The mean body mass index (BMI) was 22.7 +/- 3.7. The average LBM-AM was 43.6 +/- 8.0 kg; the average LBM-CK was 33.0 +/- 9.3 kg. The difference between the calculated LBM-AM and LBM-CK was 10.7 kg, with LBM-AM always giving a higher value; the limits of agreement were -5.8 kg and 27.1 kg. The difference between the two measures correlated with residual GFR (Pearson r = 0.629, p < 0.001). After normalizing for desired body weight, LBM-AM was only modestly correlated with serum albumin level. No correlations were found between overall SGA score or normalized protein nitrogen appearance (nPNA) and LBM-AM or LBM-CK. CONCLUSIONS: In Chinese patients at least, a substantial discrepancy exists between LBM-AM and LBM-CK. The difference is especially marked in patients with significant residual renal function. The optimal method for determining LBM remains obscure in Chinese CAPD patients. Moreover, LBM correlated poorly with other nutritional indices. Multiple parameters should be taken into consideration in an assessment of nutritional status of CAPD patients.

Anthropometry↗

Comparison of a nested polymerase chain reaction--restriction fragment length polymorphism method, the PATH antigen detection method, and microscopy for the detection and identification of malaria parasites.

A nested polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method, the PATH antigen detection method, and light microscopy were compared for their capacity to detect and identify Plasmodium species. One hundred and thirty-six blood specimens obtained from patients suspected of having malaria were examined by each of the three methods. Forty-four specimens were positive for malaria using microscopy as the "gold standard". The sensitivity for nested PCR was 100%, and the specificity was 98%. For the detection of Plasmodium falciparum, the antigen detection method had a sensitivity of 100% and a specificity of 97%. Species identification obtained using PCR-RFLP was identical or superior to light microscopy in 42 cases (96%). Although the nested PCR-RFLP method was more sensitive and specific, the rapid turnaround time and high sensitivity of the antigen detection method makes it a useful adjunct to standard microscopy.

Animals↗

Quality control including validation in dietary surveys of elderly subjects. The validation of a dietary history method (the SENECA-method) used in the 1914-population study in Glostrup of Danish men and women aged 80 years.

BACKGROUND: Quality control including validation in dietary surveys is needed to reduce and detect errors which would lead to an attenuated scientific foundation for the diet-disease relationship. Especially studies in the elderly are needed because of limited knowledge of reference values, cut-off values etc. OBJECTIVE: To validate a modified dietary history method (the SENECA-method) in elderly subjects. DESIGN: A survey of Danish men and women aged 80 years, who participated in the 1914-population study in Glostrup. SUBJECTS AND METHOD: A pilot study (n = 34) validated the dietary history against 24-h urine collections; a main study (n = 240) compared dietary history with a 3-day estimated food record. RESULTS: Protein intake from dietary history was 10% higher than calculated protein intake from 24-h urine collections. Differences in intakes of energy and macronutrients between dietary history and 3-day food record were generally small and non-significant, and there was good agreement between the methods in classifying nutrient intakes into same tertiles. A Bland & Altman plot indicated increasing differences in energy intake between methods with increased energy intake. Evidence for under-reporting of energy intake and/or over-reporting of the physical activity level was further made plausible when physical activity ratio was compared to recognized cut-off limits. CONCLUSIONS: The modified dietary history method can be used to estimate dietary intake in 80 year old subjects, but some degree of misreporting, especially under-reporting, appears to be present. Keeping this in mind it is, however, possible to analyse dietary intake against other survey data.

Aged↗

The AMeX method: a multipurpose tissue-processing and paraffin-embedding method. Extraction of protein and application to immunoblotting.

The authors have previously reported a new fixation and paraffin-embedding method (the AMeX method), which preserves many antigens as well as high molecular-weight DNA and RNA that are normally destroyed by the routine formalin fixation and paraffin-embedding process. In the present study, the authors analyzed the preservation of protein suitable for sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblotting in tissue fixed by the AMeX method. The method used for extraction of protein from AMeX-processed tissue sections after deparaffinization was the same as that for extraction from fresh tissues. The total amount of protein extracted from 50-mg (wet weight) AMeX-processed mouse liver tissue was the same as that from fresh tissue. The electrophoretic mobility and staining intensity of protein on SDS-polyacrylamide gel, and the immunoblotting pattern and staining intensity with several antibodies, were identical for both AMeX-processed and fresh tissue. Degradation of protein was minimal for storage periods of 2 years in paraffin block. The authors also showed that pellets of cultured cells can be processed by this method for immunologic analysis. This new fixation and paraffin-embedding method is a useful tool for obtaining information on correlations between morphologic features and immunochemical and molecular biological data.

Animals↗

[Counting efficacies of the CFU-enumerating method and microscopic counting method for mycobacteria located in cultured macrophages].

I compared counting efficacies of CFU-enumerating method for the number of mycobacteria (Mycobacterium intracellulare and M. fortuitum) locating in cultured macrophages with that of microscopic counting method. Zymosan A-induced macrophages from ddY mice were infected with either M. intracellulare or M. fortuitum by incubation in 10% FBS-RPMI 1640 medium containing the organisms for 1 hr, thereafter thoroughly washed to remove extracellular bacilli, and cultured for 3 to 5 days. At intervals, macrophages were thoroughly rinsed and subjected to either CFU-enumeration or microscopic counting, as follows. In the former method, macrophages were lysed with 0.2% Tween 80-distilled water by sonication using Handy Sonic and CFUs were counted on 7H11 agar plates. In the latter method, the number of acid-fast bacilli was counted by microscopy for macrophages after Ziehl-Toda's staining. The number of bacteria by the CFU-enumerating method was much greater than that by the microscopic counting method.

Cell Count↗

Susceptibility of Candida species to fluconazole assayed by a disk diffusion method with automated reading versus a microdilution method.

In vitro susceptibilities of 290 isolates of Candida spp to fluconazole were evaluated by a new NCCLS M44-P agar disk diffusion method that was read and interpreted automatically by the BIOMIC image-analysis plate reader system. Disk test results were compared to results obtained by a modified NCCLS M27-A broth microdilution method using RPMI-1640 supplemented with 2% dextrose. Overall agreement between both methods was 90.0%. Category agreement between the broth and disk test results for susceptible, susceptible dose-dependent and resistant disk results were 99.6%, 19.05% and 52.17%, respectively. No very major discrepancies, 1.03% major discrepancies, and 8.97% minor discrepancies were observed between results of the two test methods. This analysis suggests that results from both methods correlate highly for Candida strains susceptible to fluconazole. The lower agreement between the two methods for resistant and susceptible dose-dependent isolates was due to strains near or on that breakpoint, different media (Mueller-Hinton vs RPMI), agar vs broth, 80% vs 50% endpoints, and trailing growth near the endpoints.

Antifungal Agents↗

Validation study to demonstrate the equivalence of a minor modification (TECRA ULTIMA protocol) to AOAC Method 998.09 (TECRA Salmonella Visual Immunoassay) with the cultural reference method.

The TECRA Salmonella Visual Immunoassay (VIA) using Rappaport-Vassiliadis RV[R10] as a single selective enrichment broth has Final Action approval (AOAC Method 998.09). TECRA has recently developed a protocol (TECRA ULTIMA), which involves the addition of a new additive to a 1 mL aliquot of the RV[R10] broth, prior to the heat-killing step, thereby allowing the RV[R10] broth to be tested directly in the kit and thus eliminating the need for the 2 h post-enrichment in M broth. An in-house validation study was conducted to compare the modified AOAC Method 998.09 to the reference culture method. Three foods were used in the study: Naturally contaminated raw ground poultry at high (10-50 cells/25 g), and low (1-5 cells/25 g) levels; and milk powder and peanut butter, artificially inoculated at low and high levels with Salmonella bovismorbificans and S. enterica Mbandaka, respectively. Twenty test portions were analyzed for each level with 10 uninoculated control samples per food. Overall, no significant differences (p <0.05) were observed when the proportion of positive test portions for the modified VIA were compared with that for the reference method. This minor modification, which employs the additive (provided in the TECRA ULTIMA SALMONELLA Test Kit) to permit the direct analysis of RV[R10] broth has demonstrated the utility of the TECRA ULTIMA SALMONELLA protocol. It is recommended that the minor modification to Method 998.09 be approved First Action as an additional option within the method.

Animals↗

[New simple method for small, dense LDL: development of a new quantification method and clinical significance].

Small, dense LDL (S LDL) is regarded as a significant risk factor for coronary heart disease (CHD) and has also been reported its high appearance in type 2 diabetic patients. Although ultracentrifugation and electrophoresis based methods are currently used for the measurement of S LDL, such methods are either too laborious or expensive for clinical use. We have developed a simple method for quantification of S LDL. The new method consists of two steps; first to filter out large buoyant LDL and other apoB-containing lipoproteins by forming aggregates of these unintended lipoproteins with a heparin-manganese based reagent; and second to measure S LDL-cholesterol (S LDL-C) in the penetrate solution, the mixture of HDL and S LDL, on automated general chemistry analyzers. Comparison with the ultracentrifugation method yielded a correlation coefficient of 0.900 and an equation of y = 1.090x-1.8 (n = 146). Positive correlation was observed with total LDL-C level and also with triglyceride level (r = 0.782 and r = 0.526, respectively) while negative correlation was observed with LDL particle size (r = 0.658). As for the study with various types of hyperlipidemia sample, the highest level of S LDL-C was observed in combined hyperlipidemia patients. Patients with CHD had higher S LDL-C than control group (45.2 +/- 22.1 in the CHD vs. 36.7 +/- 16.9 in the control), however no difference was seen in total LDL-C level between the two groups (117.6 +/- 35.0 in the CHD vs. 115.7 +/- 30.1 in the control). Patients with type 2 diabetes also showed higher S LDL-C (54.0 +/- 22.7). S LDL-C/LDL-C ratios were also significantly higher in CHD patients and in type 2 diabetes patients than the control group (39.9 +/- 16.7 in the CHD, 37.6 +/- 13.0 in the type 2 diabetes and 31.0 +/- 9.9 in the control). Our findings suggest that this method can measure S LDL reliably with a simple procedure and that the analysis of S LDL-C can give a better index for the risk assessment of CHD than total LDL-C.

Cholesterol, LDL↗

Comparison of agar-based methods for the isolation and enumeration of heterotrophic bacteria with the new multidose IDEXX SimPlate method.

Pour and spread plates are the conventional methods of choice for the isolation and enumeration of heterotrophic microorganisms in treated water supplies. The tests are performed at 22 degrees C and 37 degrees C for 72 h and 48 h respectively. Counts at 22 degrees C are associated with pollution of water systems from external sources, while counts at 37 degrees C are used as an indication of treatment plant performance and the deterioration of the general quality of water. Conventional methods using Yeast Extract Agar for a pour plate and R2A agar for a spread plate were compared with the multidose IDEXX SimPlate method for the isolation and enumeration of heterotrophic bacteria in water. SimPlate gave a significantly higher count on average than the conventional methods. The R2A method showed the next highest count, being significantly higher than Yeast Extract Agar. In addition, unlike the pour and spread plate methods, SimPlate was easier to use, reduced labour, and the test results were far easier to read.

Agar↗

Evaluation of the assurance GDS for E. coli O157:H7 method and assurance GDS for shigatoxin genes method in selected foods: collaborative study.

A multilaboratory collaborative study was conducted to compare the Assurance GDS for E. coli 0157:H7 method and the reference culture methods for the detection of E. coli 0157:H7 in orange juice, raw ground beef, and fresh lettuce. A separate companion assay, the Assurance GDS for Shigatoxin Genes method was also evaluated with the same test portions. Fifteen laboratories participated in the study. A Chi square analysis of each of the 3 food types at the high, low, and uninoculated control levels was performed. For all foods, the Assurance GDS for E. coli O157:H7 method and the Assurance GDS for Shigatoxin Genes method were equivalent to or better than the reference methods.

Animals↗

[Comparison of the identification of Enterobacteriaceae by conventional method and computer analytical method].

The purpose of this study was to compare the effectiveness of identifying Enterobacteriaceae by either the conventional method or computer analytical method. The clinical isolates of 1124 species were examined by these two methods, and 1091 species had the same results. Thus the correspondence rate was 97.1%. The inconsistence of the conventional method was usually due to personal factors and the amount of the biochemical reagents. Using the computer analytical method, error due to personal reading could be eliminated. Computer analytical method is also more effective, economical, time-saving and higher in reproductability.

Computers↗

[Study of patency of minor duodenal papilla--comparison between pigment method combined with pH sensor and pancreatographic method].

We investigated the patency of minor duodenal papilla in 25 cases that had presented normal pancreatogram by using the endoscopic retrograde pancreatographic (ERP) method and a pH sensor-combined indigo carmine pigment method. The pigment method allowed us to classify the function of minor papilla into three types according to pancreatic juice excretion pre- and post-secretin administration (Type I), excretion after secretin administration (Type II), and no excretion even after secretin administration (Type III). Twelve cases belonged to Type I, 4 cases to Type II and 9 cases to Type III. By ERP method, terminal shapes of the Santorini's duct were classified as stick type, cystic type and branch type. 19 cases were considered stick type, 2 cases cystic type and 4 cases branch type. Eighteen cases were identified as patent minor papilla under ERP method. There were two cases alleged to be patent under the ERP but without pancreatic juice excretion. Therefore, the necessity of pigment method was confirmed for investigation of the function of minor papilla.

Adult↗