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PubMed2002

Evaluation of the Makromed dipstick assay versus PCR for diagnosis of Plasmodium falciparum malaria in returned travelers.

Microscopy has been the traditional reference standard for malaria diagnosis. However, difficulty in maintaining the required technical skills, particularly in areas where malaria is not endemic, has prompted the development of rapid nonmicroscopic diagnostic assays based on the detection of malaria parasite antigen in whole blood. In this study, we evaluated the performance of one such device, the Makromed dipstick test, blindly compared to PCR and microscopy for the diagnosis of Plasmodium falciparum malaria in 200 febrile returned travelers. The Makromed assay detects the presence of P. falciparum-specific histidine-rich protein II with an antigen capture immunochromatographic strip format. Compared to PCR as the reference standard, the dipstick assay had a sensitivity of 97.0% and a specificity of 96.0%. The positive and negative predictive values were 81.2% and 99.5%, respectively. Rapid malaria diagnostic devices may provide a useful diagnostic adjunct in a clinical setting.

Adolescent↗
PubMed2005

Optimised, low cost, low field dedicated extremity MRI is highly specific and sensitive for synovitis and bone erosions in rheumatoid arthritis wrist and finger joints: comparison with conventional high field MRI and radiography.

OBJECTIVE: To evaluate a low field dedicated extremity MRI unit for detection of bone erosions, synovitis, and bone marrow oedema in wrist and metacarpophalangeal (MCP) joints, with a high field MRI unit as the standard reference. METHODS: In 37 patients with RA and 28 healthy controls MRI of the wrist and 2nd-5th MCP joints was performed on a low field MRI unit (0.2 T Esaote Artoscan) and a high field MRI unit (1.0 T Siemens Impact) on 2 subsequent days. MRI was performed and evaluated according to OMERACT recommendations. Additionally, conventional x ray, clinical, and biochemical examinations were performed. In an initial low field MRI "sequence selection phase", based on a subset of 10 patients and 10 controls, sequences for comparison with high field MRI were selected. RESULTS: With high field, spin echo MRI considered as the reference method, the sensitivity, specificity, and accuracy of low field 3D gradient echo MRI for erosions were 94%, 93%, 94%, while the corresponding values for x ray examination were 33%, 98%, and 83%. Sensitivity, specificity, and accuracy of low field MRI for synovitis were 90%, 96%, and 94%, and for bone marrow oedema 39%, 99%, and 95%. Intraclass correlation coefficients between low field and high field scores were 0.936 (p<0.005) for bone erosions and 0.923 (p<0.05) for synovitis. CONCLUSION: Low field MRI provides high accuracy for detection and grading of erosions and synovitis, with high field MRI as the standard reference. For bone marrow oedema, specificity is high, but sensitivity only moderate. Low cost, patient compliant, low field dedicated extremity MRI provides similar information on bone erosions and synovitis as expensive high field MRI units.

Adult↗
PubMed1991

Identification of the in vivo metabolites of the antimalarial arteether by thermospray high-performance liquid chromatography/mass spectrometry.

The thermospray mass spectra of arteether and 16 of its potential metabolites all showed strong [M + NH4]+ ions and with only a few exceptions these compounds also showed spectral peaks corresponding to [M + NH4 - HOR]+ and [M + H - HOR]+, where OR represents the alkoxy or hydroxy group at the 12-position. A method for quantifying the metabolites was developed in which the plasma was spiked with an internal standard (the propyl ether analog of arteether), extracted using a C-18 solid-phase cartridge, then subjected to thermospray high-performance liquid chromatographic/mass spectrometric analysis using selected ion monitoring and a C-18 reversed-phase analytical column. Following the intravenous administration of arteether (11.6 mg kg-1), the plasma was found to contain 12 metabolites of arteether in the 10-1000 ng ml-1 range 15 min post-injection, and within 60 min two of these metabolites attained higher concentrations than that of the parent compound, while several other of the metabolites attained concentrations similar to the parent compound. The pseudo-first-order half-life of arteether was found to be 10.0 +/- 0.6 min, while the apparent half-lives of most of the metabolites were in the 15-30 min range. Nine of these metabolites were identified by comparison to authentic reference standards and the structures of three remaining metabolites were tentatively assigned from their spectral and chromatographic properties. The metabolic pathways leading to these 12 metabolites was a rather complex, multiple-step process, but most of the metabolites arose from an enzymatic oxidation at one of three sites; 3 alpha, 9 alpha, or the CH2 of the side-chain. Conversion of the endoperoxide group to an cyclic ether was not a major pathway. The in vitro antimalarial activity of reference standards of several of the metabolites was determined and all of those tested were found to be active in the low nanogram per milliliter range.

Animals↗
PubMed2002

Prospective validation of an echocardiographic index for determining the severity of chronic mitral regurgitation.

The aim of this study is to prospectively validate a recently reported semiquantitative index of mitral regurgitation (MR) severity. MR is a common echocardiographic finding with no single reference standard to evaluate its severity. We recently developed and retrospectively tested a semiquantitative index of MR severity. The MR index is a composite of 6 echocardiographic variables: jet penetration, proximal isovelocity surface area, continuous-wave Doppler characteristics of the regurgitant jet, pulmonary artery pressure, pulmonary venous flow pattern, and left atrial size. Sixty-two consecutive patients with varying grades of MR were prospectively studied. Patients were divided into 3 groups for comparison: mild MR, moderate MR, and severe MR. Each patient was evaluated for the 6 variables, with each variable scored on a 4-point scale (0 to 3). The reference standards for MR severity were qualitative evaluation by an expert, measurement of the regurgitant fraction (RF), and the effective regurgitant orifice area. The MR index increased in proportion to MR severity with a significant difference among the 3 groups (F = 84; p <0.0001). The MR index also correlated with RF (r = 0.73; p <0.0001) and the effective regurgitant orifice area (r = 0.74; p = 0.0001). A MR index > or = 2.2 identified 13 of 16 patients with severe MR (sensitivity 82%, specificity 98%, positive predictive value 93%). No patient with severe MR had a score <2.0 and no patient with mild MR had a score >1.67. These results concurred with those obtained in a previously published retrospective study. Thus, the MR index is a simple, reproducible semiquantitative estimate of MR severity, that is widely applicable in routine clinical practice.

Adult↗
PubMed2004

Risk of extra-oesophageal malignancies and colorectal cancer in Barrett's oesophagus and gastro-oesophageal reflux.

BACKGROUND: The relationship between Barrett's oesophagus and colorectal cancer and other extra-oesophageal malignancies (EOM) has been a matter of controversy. These relationships have therefore been examined in a prospective study design in the General Practice Research Database. METHODS: Cohorts of patients having Barrett's oesophagus (n=1677), oesophagitis (n=6392), and simple reflux (n=6328), and a standard reference cohort representing the general population in the UK (n=13,416) were selected. The last three cohorts were matched to the Barrett's cohort by general practice, age and sex. Incident outcomes occurring beyond the first year of the follow-up were used for analyses. Hazard ratios and 95% confidence intervals were calculated using Cox's proportional hazards regression. The associations with cataract and oesophageal cancer were explored for comparison. RESULTS: Incident cases of 567 EOM (including 74 colorectal cancers), 448 cataract and 43 oesophageal cancers were used in the final analysis. The relative risks for colorectal cancer compared to the standard reference cohort were 1.16 (0.42-3.21) in the Barrett's cohort, 1.39 (0.76-2.54) in the oesophagitis cohort, and 0.93 (0.45-1.90) in the simple reflux cohort. The corresponding relative risks in the Barrett's cohort were 1.29 (0.90-1.85), 1.60 (1.10-2.32), and 10.56 (5.07-21.99) for EOM, cataract and oesophageal cancer, respectively. CONCLUSIONS: The risk of colorectal cancer was not higher in any of the Barrett's oesophagus, oesophagitis, or reflux cohorts compared to the general population. The explanations for the modest increase in the risk of EOM and cataract in the above cohorts are unclear but they may be mediated by ascertainment bias or shared risk factors.

Aged↗
PubMed2004

Development of a membrane-based immunofiltration assay for the detection of T-2 toxin.

An improved analytical device capable of performing simultaneous immunofiltration-based immunoassay on 30 samples in the presence of reference standards has been developed. The device consists of a rectangular membrane with 36 antibody spotted zones, one end of which was attached to a semirigid polyethylene card. A piece of wetted filter paper between the membrane and the polyethylene card absorbs the added reagent. The assay is a competitive one using T-2 toxin-horseradish peroxidase (T-2 toxin-HRP) as the labeled analyte and 4-chloro-1 naphthol (4CN) as the substrate. Signal amplification was done by the Super-CARD signal amplification method. Semiquantitative results were obtained by visual comparison of the color intensity of a sample spot with those of reference standards. Densitometric analysis was used for quantitation. The method allows rapid and easy determination of T-2 toxin in wheat and poultry feed with detection limits of 12.5 and 25 microg x kg(-)(1), respectively, with accuracy and precision. Matrix interference was eliminated by appropriate dilution of sample extracts with assay buffer. The detection sensitivity in ELISA was 10-fold higher than that in the membrane-based method. Noninfected samples were spiked with T-2 toxin at several concentrations and analyzed by the present method and rapid ELISA. Mean recoveries by both methods were between 80 and 108%. The correlation between the two methods was excellent (R(2) = 0.99).

Animal Feed↗
PubMed2000

Caries inhibition efficacy of an antiplaque/antigingivitis dentifrice.

PURPOSE: To evaluate the efficacy of a fluoride dentifrice containing a fixed combination of essential oils (Thymol, Menthol, Eucalyptol, and Methyl Salicylate) in preventing caries in Sprague Dawley rats. MATERIALS AND METHODS: The dentifrice contains 0.76% sodium monofluorophosphate (SMFP) as the fluoride source and a silica abrasive system. A fluoride-free placebo and a clinically proven USP dentifrice reference standard for SMFP/silica were included as controls. Three groups of 45 SDV-free Sprague Dawley weanlings were infected by a cariogenic strain of Streptococcus sobrinus and fed cariogenic diet NIH 2000 ad libitum. Animals were treated twice daily (once on weekends) with the assigned dentifrice using a cotton-tipped applicator, for 5 wks, after which they were terminated and caries scored using Larson's modification of the Keyes method. RESULTS: Analyses of variance were used to compare inter-group means, the total E lesion score was the primary efficacy variable. Compared with the fluoride-free vehicle control, the experimental dentifrice and USP reference standard dentifrice produced a statistically significant reductions of 18.3% and 12.2% respectively for total caries score (P<0.001). Compared with the clinically tested USP positive control dentifrice, the experimental dentifrice produced a statistically significant reduction in the total caries score of 6.9% (P=0.028). The results of this study show that 1) both the new dentifrice containing essential oils and USP dentifrice are statistically significantly effective in reducing caries in the rat model, 2) the anticaries activity of the SMFP dentifrice is not adversely affected with the addition of essential oils.

Analysis of Variance↗
PubMed2007

Chronic tibiofibular syndesmosis injury of ankle: evaluation with contrast-enhanced fat-suppressed 3D fast spoiled gradient-recalled acquisition in the steady state MR imaging.

PURPOSE: To retrospectively determine the accuracy of coronal contrast material-enhanced fat-suppressed three-dimensional (3D) fast spoiled gradient-recalled acquisition in the steady state (SPGR) magnetic resonance (MR) imaging, as compared with that of routine transverse MR imaging, in the assessment of distal tibiofibular syndesmosis injury, with arthroscopy as the reference standard. MATERIALS AND METHODS: The review board of the College of Medicine in Yonsei University approved this study; informed consent was waived. The study group comprised 45 patients (26 men, 19 women; mean age, 32.1 years; range, 18-58 years) with a chronic ankle injury who had undergone MR imaging and arthroscopic surgery. Three independent readers retrospectively reviewed the two sets of MR images (one set of gadolinium-enhanced 3D fast SPGR images and one set of routine T1-, T2-, and intermediate-weighted images). Scores from 1 to 5 in increasing order of the probability of injury were assigned to both sets. Arthroscopy was the reference standard. Syndesmotic recess height was measured on contrast-enhanced images. The two sets of images were compared for diagnostic performance with receiver operating characteristic (ROC) analysis. Dissection and histologic examination of six cadaveric ankles was performed to assess the syndesmotic area and ascertain the enhancing structure at MR imaging. RESULTS: At arthroscopy, syndesmotic injury was found in 24 ankles but not in 21 ankles. Areas under the ROC curve were significantly higher for the contrast-enhanced images (P<.05). The contrast-enhanced set showed higher accuracy, sensitivity, and specificity compared with the routine set for the assessment of syndesmosis injury. Mean syndesmotic recess height was significantly greater (P<.05) in patients with syndesmotic injury. Dissection and histologic examination revealed a highly vascular synovial fold in the syndesmotic area that is expected to enhance at MR imaging. CONCLUSION: In the assessment of chronic syndesmosis injury, coronal gadolinium-enhanced fat-suppressed 3D fast SPGR MR images were more sensitive, specific, and accurate than routine MR images.

Adipose Tissue↗
PubMed2000

A comparative study on hypocholesterolaemic effect of allicin, whole germinated seeds of bengal gram and guggulipid of gum gugglu.

The daily use of allicin and whole germinated bengal gram seeds for 8 weeks led to a significant decrease in serum cholesterol levels in normal volunteers with no side effects. The standard reference, guggulipid therapy, significantly (p < 0.001) reduced the mean serum cholesterol level to 142.88 +/- 24.14 mg/100 mL from an initial status of 211.91 +/- 6.23 mg/100mL (32.36% +/- 12.48% fall). Allicin treatment significantly reduced the mean serum cholesterol level to 129.99 +/- 2.79 mg/100 mL from a pre-treatment value of 148.10 +/- 8. 81 mg/100mL, a fall of 13.36% +/- 4.64%. The serum cholesterol value was reduced to 135.62+/- 22.85 mg/100 mL from a pre-treatment value of 157.29 +/- 4.94 mg/100mL (17.15% +/- 9.94% fall) due to daily use of whole germinated bengal gram seeds. Hence the hypocholesterolaemic effects of allicin and whole germinated bengal gram seeds are comparable to the established standard reference, guggulipid. These two materials are herbal in origin and it is supposed to have a lesser risk-benefit ratio compared with other available synthetic drugs. The inclusion of these herbal products in the normal diet may be an alternative effective measure for hypercholesterolaemia.

Adult↗
PubMed1989

National Institute of Mental Health Treatment of Depression Collaborative Research Program. General effectiveness of treatments.

We investigated the effectiveness of two brief psychotherapies, interpersonal psychotherapy and cognitive behavior therapy, for the treatment of outpatients with major depression disorder diagnosed by Research Diagnostic Criteria. Two hundred fifty patients were randomly assigned to one of four 16-week treatment conditions: interpersonal psychotherapy, cognitive behavior therapy, imipramine hydrochloride plus clinical management (as a standard reference treatment), and placebo plus clinical management. Patients in all treatments showed significant reduction in depressive symptoms and improvement in functioning over the course of treatment. There was a consistent ordering of treatments at termination, with imipramine plus clinical management generally doing best, placebo plus clinical management worst, and the two psychotherapies in between but generally closer to imipramine plus clinical management. In analyses carried out on the total samples without regard to initial severity of illness (the primary analyses), there was no evidence of greater effectiveness of one of the psychotherapies as compared with the other and no evidence that either of the psychotherapies was significantly less effective than the standard reference treatment, imipramine plus clinical management. Comparing each of the psychotherapies with the placebo plus clinical management condition, there was limited evidence of the specific effectiveness of interpersonal psychotherapy and none for cognitive behavior therapy. Superior recovery rates were found for both interpersonal psychotherapy and imipramine plus clinical management, as compared with placebo plus clinical management. On mean scores, however, there were few significant differences in effectiveness among the four treatments in the primary analyses. Secondary analyses, in which patients were dichotomized on initial level of severity of depressive symptoms and impairment of functioning, helped to explain the relative lack of significant findings in the primary analyses. Significant differences among treatments were present only for the subgroup of patients who were more severely depressed and functionally impaired; here, there was some evidence of the effectiveness of interpersonal psychotherapy with these patients and strong evidence of the effectiveness of imipramine plus clinical management. In contrast, there were no significant differences among treatments, including placebo plus clinical management, for the less severely depressed and functionally impaired patients.

Adult↗
PubMed2000

Noninvasive tests as a substitute for histology in the diagnosis of Helicobacter pylori infection.

BACKGROUND: Rapid urease tests for Helicobacter pylori have a sensitivity of 80% to 90%. Therefore histologic examination of gastric biopsies is recommended as a "backup" diagnostic test in rapid urease test-negative patients. However, noninvasive tests (urea breath test, serology, whole blood antibody tests) may provide a more rapid diagnosis and be less expensive but offer similar accuracy. METHODS: Sixty-seven patients (no prior treatment for H pylori, no proton pump inhibitors, antibiotics, or bismuth within 4 weeks) undergoing endoscopy for evaluation of dyspepsia symptoms and testing rapid urease test-negative by antral biopsy were enrolled. All had the following tests: gastric biopsies (2 antral, 1 fundus; H&E and Alcian Yellow stain) examined for gastritis and H pylori; (13)C-UBT; capillary blood for whole blood rapid antibody tests: FlexSure HP, QuickVue, AccuStat, and Stat-Simple Pylori; serum for FlexSure HP; HM-CAP enzyme-linked immunoassay. H pylori infection was diagnosed (reference standard) if chronic gastritis was present on histology and at least 2 of the 3 following tests were positive: urea breath test, H pylori organisms unequivocally demonstrated in biopsies on special stain, and/or enzyme-linked immunoassay. The test and treatment costs per patient were calculated. RESULTS: Of 67 patients with a negative rapid urease test, 4 were positive for H pylori. None had active peptic ulcer disease. Histology only identified 1 patient with organisms visible on special stain. Using chronic active gastritis (neutrophilic and mononuclear infiltrate) as a diagnostic criterion for H pylori, 6 patients would have been judged positive. However, only 2 of these were truly positive by the reference standard (positive predictive value 33%). Negative predictive value for presence of organisms and chronic active gastritis was 95% and 97%, respectively. All of the noninvasive tests identified all 4 truly positive patients correctly. Urea breath test and FlexSure whole blood assay yielded a substantial number of false-positive results (positive predictive value 31% and 36%, respectively); positive predictive value for the other tests ranged from 50% to 80%. All tests except histology had a negative predictive value of 100%. Histology was the most costly test (p < 0. 001 compared with all other tests), followed by urea breath test and HM-CAP serology (p < 0.001 compared with all rapid antibody tests). CONCLUSIONS: Whole blood or serum antibody testing is a rapid, accurate, and cost-effective means for establishing H pylori status in rapid urease test-negative patients. Whole blood or serology rapid antibody testing should substitute for histology when the patient has not been previously treated for H pylori.

Adult↗
PubMed2004

The diagnostic randomized clinical trial is the best solution for management issues in critical limb ischemia.

OBJECTIVE: The value of a new diagnostic test is usually established by analyzing its accuracy in relation to a reference standard. Here we describe a potentially better model of diagnostic research, namely, a diagnostic randomized clinical trial (D-RCT), and discuss its pros and cons using management of critical limb ischemia as an example. STUDY DESIGN AND SETTING: Patients clinically suspected of critical limb ischemia are randomized either for the conventional management strategy (treating physician determines the diagnostic and therapeutic strategy on clinical judgment and ankle pressure) or new strategy (transcutaneous oxygen and toe pressure determine the diagnostic and therapeutic strategy). The effect of the diagnostic work-up on the diagnostic and therapeutic process and clinical outcome will be evaluated. RESULTS: A D-RCT is suited when a true reference standard is lacking. It is the best available research method to control for confounding and bias, and it also incorporates the total effect (interpretation and side effects) on clinical outcome. The D-RCT has some disadvantages, however, as to the power and size of the trial and the influence of treatment on the outcome parameter. CONCLUSIONS: A D-RCT can provide valuable information as to the evaluation of diagnostic tests.

Ankle↗
PubMed1993

Identification of four biliary metabolites of the diterpene sclareol in the laboratory rat.

1. Ag.l.c. method was developed to determine sclareol (1) and its microbial metabolites: 3-keto-sclareol (2), 2 alpha-hydroxysclareol (3), 3 alpha-hydroxysclareol (4), 3 beta-hydroxysclareol (5), 18-hydroxysclareol (6), and 2 alpha, 18-dihydroxysclareol (7) in both microbial cultures and biological fluids of the laboratory rat. 2. Metabolism of the diterpene (1) was studied in the laboratory rat. This in vivo study was facilitated by the availability of microbial metabolites of sclareol as reference standards, and the g.l.c. assay for sclareol and its metabolites in biological fluids. 3. Following i.v. treatment (100 mg/kg), the disappearance of (1) from rat plasma was rapid and biphasic. No microbial metabolites of sclareol were detectable in plasma. 4. Sclareol (1) and its microbial metabolites were not detected in rat urine following either i.v. or oral treatments; unchanged (1) was excreted in rat faeces to the extent of 9% of an oral dose in 48 h. 5. Following i.v. treatment, 0.02% dose was recovered in bile as unchanged (1). Four biliary metabolites of (1) (0.4% dose) were identified as (2), and (4)-(6) based on g.l.c.-mass spectrometry and comparisons with reference standards. All four biliary metabolites of (1) in rat have been identified as microbial metabolites of (1).

Animals↗
PubMed2004

Accuracy of human papillomavirus testing in primary screening of cervical neoplasia: results from a multicenter study in India.

The knowledge that cervical neoplasia are caused by human papillomavirus (HPV) infection has led to the evaluation of its role in screening. We evaluated the accuracy of HPV testing by Hybrid capture II (HC II) method in detecting cervical intraepithelial neoplasia grade 2 and 3 (CIN 2 and 3) lesions in 4 cross-sectional studies with common protocol and questionnaire in 3 different locations (Kolkata, Mumbai and Trivandrum) in India. These studies involved 18,085 women aged 25-65 years. The reference standard for final diagnosis was a combination of colposcopy/biopsy. All women were investigated with colposcopy and 3,116 received directed biopsy. The sensitivity of HPV testing for detecting CIN 2-3 lesions varied from 45.7% to 80.9% across the study sites; the specificity varied from 91.7% to 94.6% and the positive predictive value from 6.7% to 13.7%. Retesting of 298 randomly chosen denatured samples in France revealed an agreement rate of 85.9% and a kappa-value of 0.72. Although HPV testing seems to be a promising approach for cervical cancer prevention, a large range in sensitivity was observed in our study, possibly due to variations in the quality of specimen collection and reference standards. A higher sensitivity was associated with the center performing the test well. Further developments in terms of more reproducible, less expensive and less sophisticated testing are essential to make the test feasible and effective in low-resource settings.

Adult↗
PubMed1996

Microwave digestion using dual PTFE containers for analysis of trace elements in small amounts of biological samples.

The analysis of trace elements in biological samples is essential to extend our knowledge on human health and disease. Inductively coupled plasma mass spectrometry (ICP-MS) makes it possible to simultaneously determine these elements in trace amounts. Before analysis, however, biological samples such as organs and tissues must be liquefied and extra organic materials must be decomposed by acid digestion. We established a method of microwave digestion using dual PTFE containers to minimize the amount of samples. Samples (35-45 mg) of standard reference materials, bovine liver (1577a, NIST) and fish flesh (MA-A-2, IAEA), were weighed in PTFE-PFA vials and a small amount of nitric acid (0.5 ml) was added. The vials were sealed and two PTFE-PFA vials were placed in a PTFE-TFM vessel containing 6 ml of pure water. Then the vessels were placed in a rotor and the samples were digested for 38 min in a microwave oven according to a pre-set program. After the program was completed, the samples were analyzed by ICP-MS. The determined values of elements of the microwave-digested samples matched the certified values of the standard reference materials. Therefore, the digestion using dual containers was successfully applied to small samples.

Animals↗
PubMed2005

Plant DNA flow cytometry and estimation of nuclear genome size.

BACKGROUND: DNA flow cytometry describes the use of flow cytometry for estimation of DNA quantity in cell nuclei. The method involves preparation of aqueous suspensions of intact nuclei whose DNA is stained using a DNA fluorochrome. The nuclei are classified according to their relative fluorescence intensity or DNA content. Because the sample preparation and analysis is convenient and rapid, DNA flow cytometry has become a popular method for ploidy screening, detection of mixoploidy and aneuploidy, cell cycle analysis, assessment of the degree of polysomaty, determination of reproductive pathway, and estimation of absolute DNA amount or genome size. While the former applications are relatively straightforward, estimation of absolute DNA amount requires special attention to possible errors in sample preparation and analysis. SCOPE: The article reviews current procedures for estimation of absolute DNA amounts in plants using flow cytometry, with special emphasis on preparation of nuclei suspensions, stoichiometric DNA staining and the use of DNA reference standards. In addition, methodological pitfalls encountered in estimation of intraspecific variation in genome size are discussed as well as problems linked to the use of DNA flow cytometry for fieldwork. CONCLUSIONS: Reliable estimation of absolute DNA amounts in plants using flow cytometry is not a trivial task. Although several well-proven protocols are available and some factors controlling the precision and reproducibility have been identified, several problems persist: (1) the need for fresh tissues complicates the transfer of samples from field to the laboratory and/or their storage; (2) the role of cytosolic compounds interfering with quantitative DNA staining is not well understood; and (3) the use of a set of internationally agreed DNA reference standards still remains an unrealized goal.

Cell Nucleus↗
PubMedDate not supplied

The use of parent report to assess the quality of care in primary care visits among children with asthma.

OBJECTIVE: To determine the accuracy of parent report and the accuracy of the medical record in documenting physician performance of elements of pediatric asthma care in the primary care setting. METHODS: A convenience sample of 79 English-speaking parents of 4--12-year old children with asthma presenting to medical center--affiliated inner-city primary care pediatric clinics in the Bronx, Dallas, and Chicago was enrolled, and the office visit was audiotaped. Parents were interviewed 1--16 days after the visit by telephone. OUTCOME MEASURES: Accuracy of parent report was the primary outcome. The "reference standard" was an independent evaluation of the audiotaped record of the primary care visit. The National Asthma Education and Prevention Program was used as a guide to select data elements to assess quality of pediatric asthma care during primary care visits. RESULTS: Sufficient documentation was significantly (P <.001) less likely to be present in the medical record than in the follow-up interview for each element of care. When these elements were combined into a cumulative score, 71% of parent interviews but only 37% of medical records scored > or = 5 (out of a possible 6), with 29% of medical records scoring < 3. Parents were able to accurately report (concordance of parent data with audiotape reference standard) whether or not the visit had included performance of 5 of the 6 elements of care. CONCLUSIONS: Our study suggests that parent telephone interview within 2 weeks after the visit is more accurate than the medical record for documentation of the quality of asthma care in pediatric primary care visits. The medical record was not sufficient to assess the quality of primary care related to asthma, primarily because of missing data. Therefore, our data suggest that assessing quality of care using the medical record will not only bias the findings in the direction of more deficient care but will also make improvement in care more difficult. Further validation of our strategy for using parent report to assess the quality of care in primary care visits will require its application in a variety of other primary care settings.

Asthma↗
PubMed2000

Comparative study of two different TRUS-guided sextant biopsy techniques in detecting prostate cancer in one biopsy session.

OBJECTIVE: The aim of this study was to compare a transrectal ultrasound (TRUS)-guided sextant biopsy technique, which puts more emphasis on the apical region of the prostate where most prostate carcinomas (PCs) develop, with the standard sextant biopsy technique. METHODS: A total of 280 patients with suspected PC were included in this analysis. Twelve biopsy cores were obtained from all patients. Six biopsy cores were taken within a lateral parasagittal plane from each lobe at the apex, middle and basis, with an angle of approximately 45 degrees (technique A), and 6 further biopsy cores were taken from the left to the right lateral margin always penetrating the prostate in the apex with the same angle (socalled fan-shaped technique, technique B). Technique A predominantly samples in the sagittal and technique B samples more in the transversal plane with emphasis on the apical region where most PCs develop. The sensitivity in detecting PCs for both techniques was calculated and correlated to the serum prostate-specific antigen (PSA) levels. RESULTS: A total of 72 PCs (25.7%) were diagnosed. We subsequently performed subgroup analysis depending on the serum PSA levels: in patients with a PSA of </=10 ng/ml (n = 27) technique A has a PC sensitivity of 88.8% (p = 0.037) and technique B 96.2% (p = 0.326) as compared to our reference standard of 100% by sampling 12 biopsy cores in the same prostate. The number of positive biopsy cores using technique B was superior in 12 cases as compared to 3 cases with technique A (p = 0.04). In 12 patients the number of positive biopsy cores was identically. In patients with a PSA of >10 ng/ml (n = 45) technique A has a PC sensitivity of 93.3% (p = 0.083) and technique B 88.8% (p = 0.023) as compared to our reference standard. The number of positive core biopsies using technique A was superior in 14 cases as compared to 12 with technique B (p = 0.154). In 19 patients the number of positive biopsies was identical. CONCLUSION: Our data suggest that in patients with PSA of </=10 ng/ml technique B bring significant benefit with regard to the number of positive core biopsies, as well as an enhanced PC detection rate which is near the 12-core biopsy. Due to the fact that technique B samples more in the apical region where most cancers develop, it should be performed in suspected early stage cancers of the prostate (PSA</=10 ng/ml).

Adolescent↗