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PubMed1994

Inorganic pyrophosphatase-based detection systems. II. Detection and quantification of cell lysis and cell-lysing activity.

A novel technique, useful for detection of cell lysis and cell-lysing activity, has been developed. The method can be used for detection of cell lysis, both induced and natural, in all types of cells. The technique can be used for detection and quantification of all types of cell-lysing activities, e.g., cell wall hydrolases, toxicants, phospholipases, and antibiotics. The method relies on the detection, by a very sensitive enzymatic luminometric inorganic pyrophosphate detection assay (ELIDA; P. Nyrén and A. Lundin (1985) Anal. Biochem. 151, 504-509) of an enzyme, inorganic pyrophosphatase, which is constitutively expressed in all cells. The fraction of lysed cells in a sample can be assessed by determining the activity in the absence and in the presence of total lysing activity. The technique was used for determination of the effect of storage conditions on the intactness of two different cells, Micrococcus luteticus and Saccharomyces cerevisiae. In a model system, the approach was also used for detection of cell-lysing activity. The activity of a cell wall hydrolase (lysozyme) and a surfactant (Triton X-100) was quantified. M. luteticus cells were incubated with a specific buffer containing the lysing activity and inorganic pyrophosphate. The amount of unhydrolyzed PPi was determined by the ELIDA. The amount of PPi hydrolyzed was proportional to the amount of lysozyme present. The sensitivity of the assay was dependent on several factors, such as amount of cells used, incubation time, and incubation temperature. Lysozyme at concentrations below 5 ng/ml (< 50 pg) could be detected. The possibility of using the approach for detection of other types of cell-lysing activities is discussed.(ABSTRACT TRUNCATED AT 250 WORDS)

Bacteriolysis↗

PubMed2001

Comparisons of cancer detection rate and costs of one cancer detected among different age-cohorts in immunochemical occult blood screening.

PURPOSE: This study was carried out to compare the detection rate for colorectal cancer and the average costs to detect one patient with colorectal cancer among three different age-cohorts in immunochemical occult blood screening by OC-Hemodia. METHODS: In a population-screening program, 17,432 subjects received an immunochemical fecal occult blood test. In a medical checkup for colorectal cancer 7,232 subjects received colonoscopy. They were divided into three groups according to their ages: younger (4,049 years); middle (50-59); and older (60+) groups. The detection rate for colorectal cancer and the average costs to detect one patient with colorectal cancer were evaluated among the three groups. RESULTS: In the screening program-based study, the cancer detection rate and the average costs for one colorectal cancer detected were calculated as 0.09% and $13,352, 0.28% and $4,555, 0.29% and $4,461 for the younger, middle, and older groups, respectively. In addition, in the medical checkup-based study, the detection rate and the average costs were calculated as 0.3% and $6,851, 1.5% and $1,517, 1.7% and $1,391 for the younger, middle, and older groups, respectively. In these two studies, the cancer detection rates were significantly different between the younger and middle groups (P < 0.05), and between the younger and older groups (P < 0.05). CONCLUSIONS: These findings indicate that the subjects aged under 50 have some disadvantage when carrying out the immunochemical fecal occult blood test--OC-Hemodia for colorectal cancer screening--from the viewpoint of screening efficiency as well as cost-effectiveness.

Adult↗

PubMed2004

Determination of the interdetector volume by s-detection in size-exclusion chromatography of polymers with on-line multiangle light-scattering detection.

The determination of the interdetector volume (IDV) in size-exclusion chromatography (SEC) of polymers with dual multiangle light-scattering/concentration detection based on the s-detection is demonstrated. By s-detection the determination is meant of local molecular mass from a known relation between molecular mass and radius of gyration, obtained from the angle dependence of the intensity of scattered light. IDV is found basing on the stipulation of equal slope of local calibrations found by the dual light-scattering/concentration detection, referred to as the w- and s-detection. As the s-detection uses just the light-scattering detector and, therefore, is independent of the value of IDV, this quantity can be found by searching for its value that gives the local calibration dependence obtained by the dual detection closest to that determined independently by the s-detection.

Calibration↗

PubMed2005

Integrated capillary electrophoresis amperometric detection microchip with replaceable microdisk working electrode. II. Influence of channel cross-sectional area on the separation and detection of dopamine and catechol.

The interference of separation high voltage with the electrochemical detection is a major challenge to the microchip capillary electrophoresis-electrochemical detection systems with end-channel detection mode. Using dopamine and catechol as model analytes, the influences of channel cross-sectional area and channel-to-electrode distance on the high-voltage interference, accordingly on the separation and detection performances of the microchip capillary electrophoresis-electrochemical detection system were investigated. With the increase of the channel cross-sectional area from 312 through 450-615 microm2, the apparent half-wave potentials of hydrodynamic voltammetry for dopamine at the field strength of 288 V/cm shifted positively from 285 through 330-400 mV. By using a chip with the smallest channel cross-section (312 microm2 with top width of 37.3 microm and depth of 8.9 microm) the residual high-voltage field in the detection cell was small, so that detection was conducted at a channel-to-electrode distance of 20 microm to achieve better performances of separation and detection.

Catechols↗

PubMed1998

Seizure detection using a self-organizing neural network: validation and comparison with other detection strategies.

OBJECTIVE: A previously described seizure detection algorithm (CNET) (Gabor, A.J., Leach, R.R. and Dowla, F.U. Automated seizure detection using a self-organizing neural network. Electroenceph. clin. Neurophysiol., 1996, 99: 257-266) was validated with 200 records from 65 patients (4553.8 h of recording) containing 181 seizures. DESIGN AND METHODS: Performance of the algorithm was manifest by its sensitivity ((seizures detected/total seizures) x 100) and selectivity (false-positive errors/Hr-FPH). Comparisons with the Monitor detection algorithm (Version 8.0c, Stellate Systems) and audio-transformation (Oxford Medilog) were performed. RESULTS: CNET detected 92.8% of the seizures and had a mean FPH of 1.35 +/- 1.35. Monitor detected 74.4% of the seizures and had a mean FPH of 3.02 +/- 2.78. Audio-transformation detected all but 3 (98.3%) of the seizures. Selectivity for this detection strategy was not defined. CONCLUSIONS: This study not only validates the CNET algorithm, but also the notion that seizures have frequency-amplitude features that are localized in signal space and can be selectively identified as being distinct from other types of EEG patterns. The ear is a specialized frequency-amplitude detector and when the signal is transformed into audio frequency range (audio-transformation), seizures can be detected with better sensitivity as compared to the other strategies examined.

Adolescent↗

PubMed2000

Separation of metalloporphyrins by capillary electrophoresis with UV detection and inductively coupled plasma mass spectrometric detection.

Vitamin B12, cobalt protoporphyrin, manganese protoporphyrin, and zinc protoporphyrin were separated using capillary electrophoresis, and a comparison was made between detection with inductively coupled plasma mass spectrometry (ICP-MS) and UV detection. Absolute limits of detection were slightly better with ICP-MS detection than with UV detection, but for both methods absolute detection limits were in the picogram range. The migration times of the analytes decreased by several minutes when ICP MS detection was employed, and this phenomenon was believed to be a result of a "suction effect" that developed when the CE capillary was interfaced to the ICP-MS nebulizer. However, the resolution between species containing the same metal atom was not altered significantly, and the separation was completed in much less time relative to separations performed with UV detection.

Electrophoresis, Capillary↗

PubMed1987

Detection of trace levels of trichothecene mycotoxins in environmental residues and foodstuffs using gas chromatography with mass spectrometric or electron-capture detection.

Methods are described for the simultaneous detection of a wide range of trichothecenes, including the most polar ones and some macrocyclics, using either gas chromatography-mass spectrometry with selected ion monitoring, or gas chromatography with electron-capture detection. Trichothecenes were extracted directly from the various matrices, or from Clin Elut columns, and cleaned up on Florisil Sep-Pak cartridges. Macrocyclics and neosolaniol were detected after hydrolysis to verrucarol and T-2 tetraol respectively. For optimum sensitivity (0.5-10 ng per sample) over the range, trichothecenes were detected, both before and after hydrolysis of ester groups, as their heptafluorobutyrate derivatives using a quadrupole mass spectrometer and negative ion chemical ionisation. The use of a magnetic sector instrument with electron-impact ionisation gave comparable sensitivity for most trichothecenes, but was less useful for the simultaneous detection of verrucarol in the presence of other trichothecenes. The methods were used to detect the presence of scirpentriol, nivalenol and 15-monoacetoxyscirpendiol in sorghum from Thailand. Trichothecenes in less complex matrices could be detected, after hydrolysis, using gas chromatography with electron-capture detection.

Chemical Phenomena↗

PubMed2001

Analysis of native proteins from biological fluids by biomolecular interaction analysis mass spectrometry (BIA/MS): exploring the limit of detection, identification of non-specific binding and detection of multi-protein complexes.

Biomolecular interaction analysis mass spectrometry (BIA/MS) is a two-dimensional analytical technique that quantitatively and qualitatively detects analytes of interests. In the first dimension, surface plasmon resonance (SPR) is utilized for detection of biomolecules in their native environment. Because SPR detection is non-destructive, analyte(s) retained on the SPR-active sensor surface can be analyzed in a second dimension using matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry. The qualitative nature of the MALDI-TOF MS analysis complements the quantitative character of SPR sensing and overcomes the shortcomings of the SPR detection stemming from the inability to differentiate and characterize multi-protein complexes and non-specific binding. In this work, the benefit of performing MS analysis following SPR sensing is established. Retrieval and detection of four markers present in biological fluids (cystatin C, beta-2-microglobulin, urinary protein 1 and retinol binding protein) was explored to demonstrate the effectiveness of BIA/MS in simultaneous detection of clinically related biomarkers and delineation of non-specific binding. Furthermore, the BIA/MS limit of detection at very low SPR responses was investigated. Finally, detection of in-vivo assembled protein complexes was achieved for the first time using BIA/MS.

Biomarkers↗

PubMed2004

Detection and classification performance levels of mammographic masses under different computer-aided detection cueing environments.

RATIONALE AND OBJECTIVES: The authors evaluated the impact of different computer-aided detection (CAD) cueing conditions on radiologists' performance levels in detecting and classifying masses depicted on mammograms. MATERIALS AND METHODS: In an observer performance study, eight radiologists interpreted 110 subtle cases six times under different display conditions to detect depicted masses and classify them as benign or malignant. Forty-five cases depicted biopsy-proven masses and 65 were negative. One mass-based cueing sensitivity of 80% and two false-positive cueing rates of 1.2 and 0.5 per image were used in this study. In one mode, radiologists first interpreted images without CAD results, followed by the display of cues and reinterpretation. In another mode, radiologists viewed CAD cues as images were presented and then interpreted images. Free-response receiver operating characteristic method was used to analyze and compare detection performance. The receiver operating characteristic method was used to evaluate classification performance. RESULTS: At these performance levels, providing cues after initial interpretation had little effect on the overall performance in detecting masses. However, in the mode with the highest false-positive cueing rate, viewing CAD cues immediately upon display of images significantly reduced average performance for both detection and classification tasks (P < .05). Viewing CAD cues during the initial display consistently resulted in fewer abnormalities being identified in noncued regions. CONCLUSION: CAD systems with low sensitivity (< or = 80% on mass-based detection) and high false-positive rate (> or = 0.5 per image) in a dataset with subtle abnormalities had little effect on radiologists' performance in the detection and classification of mammographic masses.

Area Under Curve↗

PubMed1999

Detection of peptides by precolumn derivatization with biuret reagent and preconcentration on capillary liquid chromatography columns with electrochemical detection.

The separation and detection of biuret complexes of neuropeptides by capillary liquid chromatography with electrochemical detection was explored. Capillaries of 25-micron inner diameter packed with base-resistant, polymer-based reversed-phase particles were used for separation, and C-fiber electrodes were used for detection. Detection at the C-fiber electrode was found to have some differences in relative sensitivity for peptides compared to glassy carbon electrodes used previously. On-column preconcentration of preformed complexes allowed up to 1-microL samples to be injected with minimal band broadening resulting in a 100-fold improvement in concentration detection limit with no effect on mass detection limit. Concentration detection limits ranged from 5 to 59 pM, depending upon the peptide, corresponding to 5-59 amol injected. The low concentration detection limit was possible because of minimal baseline disturbances, minimal formation of unwanted products, and high efficiency of complex formation associated with biuret derivatization. The method was applied to determination of vasopressin and bradykinin in dialysates collected with 5-min sampling frequency from the rat supraoptic nucleus.

Animals↗

PubMed1999

Whole-column radioactivity detection: simultaneous separation and enhanced detectability.

The development of a whole-column radiation detector for measurement and separation of low amounts of beta emitting analytes is described. The design of this detector is unique with all of the chromatography media located within the detector volume. This whole-column design provides the advantage of increased radiation signal without loss of chromatographic efficiency, which translates to increased detectability. This increase was compared theoretically with flow-through radiation detection, and the theory was tested experimentally. Using two analytes, carbon-11-labeled m-hydroxyephedrine and alpha-methylepinephrine, only 3 and 8 Bq (80 and 220 pCi), respectively, were needed to obtain a 10% coefficient of variation using whole-column detection. For [11C]-m-hydroxyephedrine, 100 times more radioactivity was required to achieve the same coefficient of variation using flow-through detection. A limit of detection (LD) for the analytes of 2 Bq (54 pCi) was obtained for whole-column detection, an improvement of 50 in LD compared with flow-through detection. Signal improvement increased linearly with the chromatographic resolution. The whole-column detection method is robust and applicable to many chromatographic separations.

Carbon Radioisotopes↗

PubMed2003

Radiologists' detection of mammographic abnormalities with and without a computer-aided detection system.

The aim of this study was to to evaluate the role of a computer-aided program (CAD) in assisting detection of mammographic lesions by radiologists not specifically trained in mammography and its potential utility in breast screening. Mammograms were evaluated by radiologists not specifically trained in mammography first without, and then with, the CAD. Finally, the mammograms were evaluated by experienced mammographers who formed the reference standard. Two hundred and ninety four breasts were studied. In 257 breasts (87.4%), the CAD system did not help with the detection of abnormalities. It assisted radiologists in detecting abnormalities in 21 breasts (7.1%) with potential for detecting abnormalities in a further 13 breasts (4.4%). Only in three cases (1%) did it cause confusion in interpretation. There is overall increased sensitivity in detecting mammographic abnormalities with the aid of the CAD system from 74.4 to 87.2%, which is statistically significant. However, it failed to detect suspicious abnormalities in 71 breasts (24.1%). The CAD system improved detection of suspicious mammographic abnormalities by radiologists who are not specifically trained in mammography. However, there is also a substantial failure to detect suspicious mammographic features that cautions against over-reliance on the system, emphasizing its role as a second reader at best.

Breast Neoplasms↗

PubMed2001

A study of breast cancers detected in the incident round of the UK NHS Breast Screening Programme: the importance of early detection and treatment of ductal carcinoma in situ.

One hundred and seventy eight cancers detected on incident round screening in the UK National Health Service Breast Screening Programme were reviewed. Critical review of the immediately preceding screening films (from 3 years previously) found abnormalities at the site of the subsequently detected cancer in 93 cases (52%). Forty-eight of these (27% of the total) had microcalcification as the sole abnormality. All of these 48 women had invasive ductal carcinoma and/or ductal carcinoma in situ (DCIS) (including four cases in which DCIS was associated with another type of primary invasive breast cancer). The finding of microcalcification on the previous mammograms at the site of a subsequently detected cancer was a strong predictor for the presence of DCIS (with or without associated invasive disease) (P<0.0001). Of the women with invasive ductal carcinoma, those with microcalcification on previous films were significantly more likely to have intermediate or high grade (grade 2 or 3) tumours than those women without microcalcification on previous films (P=0.0015). Previous films were also read blind by two independent experienced breast radiologists. Cancers were correctly identified by one or both readers in 39 cases. However, 35 of the remaining 139 cases showed microcalcification which was not detected or considered significant by the readers. If only these 139 'true negative' screens are analysed, similar associations are seen between microcalcification on previous films and subsequent finding of DCIS (P=0.03) and between microcalcification on previous films and high grade invasive ductal carcinomas (P=0.015). These findings provide support for the hypothesis that microcalcification seen on previous screening films at the site of a subsequently detected invasive ductal carcinoma represents ductal carcinoma in situ. In this series, 19 of 82 women (23%) with invasive ductal carcinoma in the 'true negative' screen group had microcalcification suggestive of DCIS on mammograms taken, on average, 3 years previously. Significant microcalcification is often overlooked using current detection criteria. Early detection and treatment of DCIS is essential in order to prevent the development of aggressive invasive disease. Revision of the NHSBSP targets for DCIS detection is recommended.

Journal Article↗

PubMed2001

Reproductive performance of dairy cows not detected in oestrus but with a detectable corpus luteum, in response to treatment with progesterone, oestradiol benzoate and prostaglandin F2alpha.

AIM: To determine if the reproductive performance of dairy cows not previously detected in oestrus but with a detectable corpus luteum before the planned start of mating (PSM), could be improved by treatment with progesterone, oestradiol benzoate (ODB) and prostaglandin F2alpha (PGF). METHODS: Cows in 18 herds which had not been detected in oestrus, but which had a detectable corpus luteum present at veterinary examination 7 days prior to the PSM (Day -7), were allocated to 1 of 2 groups. Treated cows (n=232) received an injection of 2 mg ODB and an intravaginal progesterone releasing device (CIDR insert) on Day -7, and an injection of PGF on the day of insert removal 7 days later (Treated group). The Control group (n=243) remained untreated. Cows were mated to detected oestrus from Day 0, and conception dates confirmed by manual palpation or transrectal ultrasonography. RESULTS: During the first 7 days of mating, 37.4% of Control cows and 65.9% of Treated cows were inseminated on detection of oestrus (p<0.001). Pregnancy rates for this period were 20.4% and 36.3%, respectively (p=0.001). Conception rates to first insemination, pregnancy rates after 21 days of mating and at the end of the mating period were similar between groups (p>0.1). Median interval from the PSM to conception did not differ between treatment groups (24 and 23 days for Control and Treated, respectively, p>0.1). CONCLUSION: Treating postpartum dairy cows which had not previously been detected in oestrus but which had a detectable corpus luteum, with progesterone, ODB and PGF did not significantly improve their reproductive performance compared with no hormonal intervention.

Journal Article↗

PubMed1999

Breast tumor characteristics as predictors of mammographic detection: comparison of interval- and screen-detected cancers.

BACKGROUND: Although mammographic screening is useful for detecting early breast cancer, some tumors are detected in the interval between screening examinations. This study attempted to characterize fully the tumors detected in the two different manners. METHODS: Our study utilized a case-control design and involved a cohort of women undergoing mammographic screening within the defined population of a health maintenance organization (the Group Health Cooperative of Puget Sound). Women were classified as having "interval" or "interval-detected" cancers (n = 150) if their diagnosis was made within 24 months after a negative-screening mammogram or one that indicated a benign condition. Cancers were classified as "screen detected" (n = 279) if the diagnosis occurred after a positive assessment by screening mammography. Tumors from women in each group were evaluated for clinical presentation, histology, proliferative characteristics, and expression of hormone receptors, p53 tumor suppressor protein, and c-erbB-2 protein. RESULTS: Interval-detected cancers occurred more in younger women and were of larger tumor size than screen-detected cancers. In unconditional logistic regression models adjusted for age and tumor size, tumors with lobular (odds ratio [OR] = 1.9; 95% confidence interval [CI] = 0.9-4.2) or mucinous (OR = 5.5; 95% CI = 1.5-19.4) histology, high proliferation (by either mitotic count [OR = 2.9; 95% CI = 1.5-5.7] or Ki-67 antigen expression [OR = 2.3; 95% CI = 1.3-4.1]), high histologic grade (OR = 2.1; 95% CI = 1.2-4.0), high nuclear grade (OR = 2.0; 95% CI = 1.0-3.7), or negative estrogen receptor status (OR = 1.8; 95% CI = 1.0-3.1) were more likely to surface in the interval between screening examinations. Tumors with tubular histology (OR = 0.2; 95% CI = 0.0-0.8) or with a high percentage of in situ components (50%) (OR = 0.5; 95% CI = 0.2-1.2) were associated with an increased likelihood of screen detection. CONCLUSIONS: Our data from a large group of women in a defined population indicate that screening mammography may miss tumors of lobular or mucinous histology and some rapidly proliferating, high-grade tumors.

Adult↗

PubMed2004

The potential contribution of a computer-aided detection system for lung nodule detection in multidetector row computed tomography.

RATIONALE AND OBJECTIVES: We sought to evaluate the potential benefits of a computer-aided detection (CAD) system for detecting lung nodules in multidetector row CT (MDCT) scans. METHODS: A CAD system was developed for detecting lung nodules on MDCT scans and was applied to the data obtained from 15 patients. Two chest radiologists in consensus established the reference standard. The nodules were categorized according to their size and their relationship to the surrounding structures (nodule type). The differences in the sensitivities between an experienced chest radiologist and a CAD system without user interaction were evaluated using a chi2 analysis. The differences in the sensitivities also were compared in terms of the nodule size and the nodule type. RESULTS: A total of 309 nodules were identified as the reference standard. The sensitivity of a CAD system (81%) was not significantly different from that of a radiologist (85%; P > 0.05). The sensitivities of the CAD system for detecting nodules < or = 5 mm in diameter as well as detecting isolated nodules were higher than those of a radiologist (83% vs. 75%, P > 0.05; 93% vs. 76%, P < 0.001). The sensitivities of a radiologist for detecting nodules >5 mm and the nodules attached to other structures were higher than those of a CAD system (98% vs. 79%, P < 0.001; 91% vs. 71%, P < 0.001). There were 28.8 false-positive results of CAD per CT study. CONCLUSION: The CAD system developed in this study performed the nodule detection task in different ways to that of a radiologist in terms of the nodule size and the nodule type, which suggests that the CAD system can play a complementary role to a radiologist in detecting nodules from large CT data sets.

Adult↗

PubMed1990

Prevalence of Giardia spp. in beaver and muskrat populations in northeastern states and Minnesota: detection of intestinal trophozoites at necropsy provides greater sensitivity than detection of cysts in fecal samples.

Surveys of the prevalence of the intestinal protozoan Giardia spp. in animal populations have relied almost exclusively on the detection of cysts in fecal samples. We have determined the prevalence of Giardia spp. in beaver and muskrat populations in four northeastern states and Minnesota by using both the detection of trophozoites in mucosal scrapings from live-trapped animals at necropsy and the detection of cysts in fecal samples collected from kill-trapped animals. In muskrats the prevalence of Giardia infection was 36.6% by cyst detection in fecal samples (n = 790) from kill-trapped animals and 95.9% in live-trapped muskrats when the intestinal contents were analyzed for the presence of trophozoites (n = 219). Similarly, in beavers, Giardia infection was 9.2% by cyst detection in fecal samples (n = 662) from kill-trapped beavers and 13.7% in live-trapped animals examined for the presence of intestinal trophozoites (n = 302). The detection of trophozoites in mucosal scrapings from live-trapped animals consistently yielded a significantly higher prevalence for both muskrats and beavers than did the method based on detection of cysts in the fecal samples. The prevalence of Giardia infection in juvenile and adult live-trapped muskrats was similar (92.5 and 94.4%, respectively), but the prevalence in juvenile live-trapped beavers (23.2%) was significantly greater than that seen in the adult animals (12.6%). No difference in Giardia prevalence on the basis of sex was seen in either animal species. Regional variation, often statistically significant, was seen in the prevalence of Giardia in beavers in the northeastern states and Minnesota, but was not detected for muskrats.

Animals↗

PubMed1996

Detection of cytomegalovirus in blood donors by PCR using the digene SHARP signal system assay: effects of sample preparation and detection methodology.

Cytomegalovirus (CMV) is an important cause of transfusion-associated morbidity and mortality; however, only 0.4 to 12% of the blood products obtained from seropositive blood donors transmit infection. The effects of three commercially available whole-blood sample preparation kits on the detection of CMV PCR products by a semiquantitative adaptation of the Digene SHARP Signal System Assay (DSSSA) in samples from volunteer blood donors was assessed. Of 101 samples from seropositive blood donors, CMV was detected in 0 (0%) of the samples extracted with a QIAamp blood kit (QIAGEN), 1 (1%) of the samples extracted with an Amplicor whole-blood specimen preparation kit (Roche), and 8 (8%) of the samples extracted with an Isoquick nucleic acid extraction kit (modified by the addition of carrier tRNA) (Microprobe). CMV DNA was not detected in samples from seronegative blood donors (n = 13). Nested PCR of selected samples confirmed the detection of CMV in the sane eight samples extracted with the modified Isoquick nucleic acid extraction kit and detected an additional nine CMV-positive samples (n = 50). Samples from volunteer blood donors contain low copy numbers of CMV DNA. PCR amplification of such specimens can result in analytical sampling errors, giving results similar to the variations in titers recognized during determinations of the 50% tissue culture infective dose. The detection of CMV in blood samples from volunteer blood donors by PCR is a function of sample preparation, amplification conditions, and detection methodology. Accurate assessments of the clinical utility of CMV DNA detection by nucleic acid amplification for blood product screening and patients will require highly standardized and quantitative methodology.

Blood Donors↗