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At least 667 records · Page 37Linked to original sources
PubMed1996

[Immunoglobulin super-gene family and its related genes in detecting MRD in ALL].

OBJECTIVE: To study the rearrangements of the immunoglobulin super-gene family and its related genes, as well as their application in the detection of minimal residual disease (MRD) in acute lymphoblastic leukemia (ALL). METHODS: 15 ALL cases including 11 B-ALLs and 3 T-ALLs were studied separately by using immunophenotype detection and molecular clonging methods. RESULTS: Using DNA Southern blot analysis, we found that the rearrangement of IgH gene existed in 11 B-lineage ALL cases. The specific PCR band was visualized through amplification of the CDR3 region and J region of IgH gene. Furthermore, we sequenced the V-D-J junctional region of IgH gene in 3 B-lineage patients and synthesized two probes against the V-D-J junctional region in order to detect MRD. The hybridization results showing the sensitive of the two probes were 10(-4). In addition, we performed comparative study of MRD detection by using both T cell receptor (TCR) gamma gene as gene specific marker and SIL-TAL-1 fusion gene as tumor-specific marker in one T-ALL patient. CONCLUSION: The rearrangements of IgH gene, as well as TCR gene and tumor fusion gene can be used as specific markers in the detection of MRD in ALL.

Adolescent↗
PubMed1999

[Angioplasty with stenting in single vessel disease: non invasive methods for detecting restenosis].

OBJECTIVE: To compare the value of the myocardial perfusion imaging with 99Tc sestamibi (MIBI) with clinical data and stress EKG (SEKG) variables, in the detection of angiographic restenosis (AR: lesion > 50%), in a group of patients (pts) with single vessel disease (angiographic lesion above 70% in one epicardial artery), submitted to coronary angioplasty (PTCA) with stenting. POPULATION AND METHODS: Fifty-nine pts, followed prospectively, (49 males and 10 females aged 57 +/- 10) were submitted to 61 angioplasties, with dilatation of 59 vessels, and with stenting in 63 (1.07 stent/vessel). Clinical evaluation was performed in the first, third and sixth month, SEKG with MIBI in the fourth month and recatheterization for angiographic control in the sixth month. The pts were divided in two groups: R-positive angiographic restenosis (AR)--14 pts: NR--without AR--45 pts; the angiographic restenosis rate was 23.7%. The patients' history, cause of admission, procedure characteristics, medication at discharge, clinical events during follow-up, variables of stress EKG associated with myocardial perfusion and angiographic control were analyzed. RESULTS: The cause of admission was the same in both groups (MI in R group: 28.6%; NR: 46.7%; p = ns). There was no difference in the discharge medication. The R group was more symptomatic (Angina: R = 50.0% vs NR = 11.1%; p < 0.001 clinical restenosis rate = 11.8%), and had more revascularization procedures (PTCA: R = 57.1% vs NR = 2.8%; p < 0.001/Bypass surgery: R = 14.3% vs NR = 0%; p = 0.01). This group had abnormal stress EKG more frequently (42.9 vs 20.0%, p = ns) and ischemia in the myocardial perfusion scintigraphy (57.1 vs 6.7% p < 0.001). [table: see text] CONCLUSION: The clinical and diagnostic tests evaluated in this study showed a limited sensitivity in the detection of angiographic restenosis in a group of patients with single vessel disease submitted to coronary angioplasty and stenting. Myocardial scintigraphy was the best method for the detection of angiographic restenosis, showing a high specificity and a reasonable sensitivity.

Angioplasty↗
PubMedDate not supplied

Antivenom use in Australia. Premedication, adverse reactions and the use of venom detection kits.

OBJECTIVES: To analyse reports of antivenom use and sequelae in Australia from July 1 1989 to June 30 1990. The value of snake venom detection kits (VDKs) was also analysed. METHODS: Information was obtained from antivenom usage reports returned to the Commonwealth Serum Laboratories and from personal letters sent to those reporting doctors. Information on VDKs was obtained from antivenom usage reports or from questionnaires packaged with VDKs. RESULTS: Reported antivenoms used were: red-back spider, 258 cases; funnel-web spider, 3 cases; stonefish, 26 cases; box jellyfish, 6 cases; snake, 91 cases. Immediate reactions followed administration of red-back spider antivenom in only two patients and snake antivenoms in four patients. Delayed reactions (serum sickness) followed use of red-back spider antivenom in three patients, stonefish antivenom in two, and snake antivenoms in three. No reaction was life-threatening. Premedication was used in the majority of red-back spider bites and in 66 of 86 snake bites. Oral corticosteroids were given prophylactically after some uses of snake antivenom to prevent serum sickness. VDKs were used in 181 cases of snake bite and were reported as being useful in selecting appropriate snake antivenom in 31% of cases of antivenom use. (Only 10 of these 181 were also reported on the antivenom usage report.) Appropriate first aid was given in 61% of cases. There were 50% fewer snake bites reported than 10 years ago. CONCLUSIONS: Antivenoms in Australia are well tolerated with few immediate or delayed reactions. The use of premedication and prophylactic oral corticosteroids for four to five days after antivenom administration may be responsible for this low reaction rate. VDK results help select the appropriate antivenom; however, in some cases positive results were obtained from urine samples from patients with no symptoms of envenomation.

Adolescent↗
PubMed2005

Developmental outcome of children who had choroid plexus cysts detected prenatally.

OBJECTIVE: The purpose of this study was to evaluate cognitive, motor, language and adaptive behavior development in children who had isolated choroid plexus cysts (CPC) detected prenatally. METHODS: A retrospective double cohort design and standardized psychometric measures were used to compare the development of children who had isolated CPCs identified prenatally with a control group of children who had normal prenatal ultrasounds. RESULTS: Our study cohort (n = 37) had a mean age of 3.88 years (SD = 0.83) and the control cohort (n = 48) had a mean age of 4.62 years (SD = 1.03). The age difference between our cohorts was significant. There were no differences between cohorts in socioeconomic status, sex, birth weight or gestational age. Cognitive data showed no clinically significant difference in Full Scale IQ using the WISC-III or WPPSI-R (CPC = 113.97, control = 116.69). Scores on standardized measures of motor and adaptive functioning also did not show any significant group differences. Children with CPCs did score significantly lower than controls on some of the measures of verbal functioning; however, this difference was not associated with clinically significant delays. CONCLUSION: We conclude that the presence of isolated CPCs on midtrimester ultrasound are unlikely to be associated with any significant neurocognitive delays in early childhood.

Adaptation, Psychological↗
PubMed2005

Hearing aid use in Finnish children--impact of hearing loss variables and detection delay.

OBJECTIVE: The aim was to study the factors contributing to the mode of hearing aid use in children, with special emphasis on hearing loss variables and detection delay. METHODS: The subjects were 328 children and adolescents (58.5% boys, 41.5% girls) aged 1-18 years with hearing loss of > or =30 dB HL in the better ear fitted with hearing aid(s). The study was cross-sectional analysing the mode of using the aid binaurally/unilaterally or not at all. RESULTS: The children with hearing-impairment ranging from 50 to 90 dB HL used more regularly their hearing aids. In the subjects with hearing loss > or =80 dB HL the presence of measurable hearing threshold at 4 kHz related significantly to the acceptance of amplification (p=0.027). In 19% of the subjects hearing aid was discarded. Bilateral amplification was used in 38%. Unilateral use was the prevailing mode (44%). The younger the children (p=0.000) and the worse their hearing loss (p=0.008), the more regular their bilateral use was. Early detection of hearing loss and early hearing aid fitting promoted binaural hearing aid use (p=0.004). A marked asymmetry in pure tone thresholds was a significant audiological reason for fixed unilateral hearing device use (38%, p=0.001). CONCLUSIONS: The study shows that early detection of hearing loss and early habilitation of hearing increase bilateral use of hearing device and decrease the number of nonusers. Furthermore, residual unaided hearing at 4 kHz significantly improves the use of device.

Adolescent↗
PubMed1993

HIV DNA and antibodies in syringes from injecting drug users: a comparison of detection techniques.

OBJECTIVE: Direct HIV testing of individual injecting drug users is not always feasible. As an alternative, we have evaluated the sensitivity and specificity of several techniques for detecting HIV-1-specific products in used syringes. DESIGN: Polymerase chain reaction (PCR) and antibody-capture assays were compared using syringes prepared with blood from HIV-1-positive and -negative individuals. METHODS: PCR sensitivity was maximized, enabling detection of single copies of HIV-1-specific proviral DNA. The limits of detection from used syringes were determined for PCR by diluting extracts and correlated to CD4+ cell counts. Similarly, limits of detection were determined for enzyme immunoassays (EIA) and Western blot. RESULTS: All techniques were highly specific, although with PCR false-positives were detected occasionally. EIA proved more sensitive than Western blot in detecting needles containing HIV-1-infected individuals' blood. Even after prolonged storage of syringes at room temperature, EIA was equal to or better than PCR as an HIV-1 detection technique. The most sensitive method for detecting HIV-1 was the viral-based EIA when the recommended predilution step was omitted. CONCLUSIONS: EIA proved preferable to PCR because of their higher sensitivity, absence of false-positives and easier sample preparation and analysis.

Blotting, Western↗
PubMed1997

Comparison of a new quantitative cytomegalovirus DNA assay with other detection methods.

OBJECTIVE: We assessed a new cytomegalovirus (CMV) DNA hybridization assay. We also compared the assay with other currently used assays to determine its use in the early detection of active CMV infection. PATIENTS AND METHODS: Sequential whole blood samples collected from 109 patients who had undergone orthotopic liver transplantation were tested using the Murex hybrid capture system, cell culture, antigen detection, and serology. Liver biopsies performed during the study period for graft dysfunction in 84 patients were examined for histological features of CMV hepatitis. The biopsies were also immunostained for the presence of CMV antigens. RESULTS: Fifteen patients developed clinically significant CMV disease (CMV syndrome in six patients and CMV hepatitis in nine patients, including two patients with disseminated CMV disease). In all 15, CMV DNA was detected by the hybrid capture assay between 1 and 20 days before other CMV assays. Fourteen of the 15 patients had CMV DNA levels greater than 50 pg/ml; the other patient had a value of 48 pg/ml. Of the remaining 94 patients with no evidence of CMV disease, 86 were negative by the hybrid capture assay and 8 were positive; all but one patient had values less than 50 pg/ml. DNA levels fell rapidly in all patients during antiviral therapy. CONCLUSION: Unlike conventional CMV detection methods, this hybridization assay is an early predictor of clinically significant CMV infection after liver transplantation and also provides quantitation of viral load, allowing monitoring of antiviral therapy.

Antibodies, Viral↗
PubMed2004

[Detection of KatG 315 gene mutation associated with isoniazid resistance in Mycobacterium tuberculosis by template-directed dye-terminator incorporation with fluorescence polarization detection technology].

OBJECTIVE: To study the relationship between KatG 315 mutation and isoniazid (INH) resistance in M. tuberculosis by template-directed dye-terminator incorporation with fluorescence polarization detection (TDI-FP), and to develop a new method that can detect INH-resistant M. tuberculosis precisely and quickly. METHODS: Isolates of M. tuberculosis resistant to INH from 82 tuberculosis patients were cultured on culture medium with different INH concentrations. DNA of all M. tuberculosis samples was extracted and amplification of 271 bp KatG gene fragment was carried out by polymerase chain reaction (PCR). After digestion of the excess primers and dNTPs in PCR products by clean-up reagents, template-directed dye-terminator incorporation reaction was performed, and the Acyclo-terminators labeled Rhodamine 110 (R110) or 6-carboxytetramethylrhodamine (TAMRA) were incorporated into the detection primers specifically. Then fluorescence polarization value was measured using Victor2 multi-label counter and the genotypes of the mutation site in 315 condon of KatG gene of all samples were investigated. RESULTS: There were 15 out of the 29 isolates of M. tuberculosis with high INH-resistance showed G-->C mutation in 315 condon of KatG gene, including 4 isolates with both mutated and non-mutated trains, the mutation frequency being 52%. In 32 isolates of M. tuberculosis with low INH-resistance, 15 were mixed infection, the mutation frequency being 47%. No mutation in 315 condon of KatG gene was found in 21 susceptible isolates of M. tuberculosis. CONCLUSIONS: The G-->C mutation in 315 condon of KatG gene was associated with INH-resistance of M. tuberculosis. TDI-FP technology was a reliable, easy to use and high-through method to detect mutation of KatG gene. It may be a useful technique for the diagnosis of INH-resistance in the future.

Antitubercular Agents↗
PubMed2000

The Missing Link: Early Methane ("T") Dwarfs in the Sloan Digital Sky Survey.

We report the discovery of three cool brown dwarfs that fall in the effective temperature gap between the latest L dwarfs currently known, with no methane absorption bands in the 1-2.5 µm range, and the previously known methane (T) dwarfs, whose spectra are dominated by methane and water. The newly discovered objects were detected as very red objects in the Sloan Digital Sky Survey imaging data and have JHK colors between the red L dwarfs and the blue Gl 229B-like T dwarfs. They show both CO and CH(4) absorption in their near-infrared spectra in addition to H(2)O, with weaker CH(4) absorption features in the H and K bands than those in all other methane dwarfs reported to date. Due to the presence of CH(4) in these bands, we propose that these objects are early T dwarfs. The three form part of the brown dwarf spectral sequence and fill in the large gap in the overall spectral sequence from the hottest main-sequence stars to the coolest methane dwarfs currently known.

Journal Article↗
PubMed2004

Automated region detection based on the contrast-to-noise ratio in near-infrared tomography.

The contrast-to-noise ratio (CNR) was used to determine the detectability of objects within reconstructed images from diffuse near-infrared tomography. It was concluded that there was a maximal value of CNR near the location of an object within the image and that the size of the true region could be estimated from the CNR. Experimental and simulation studies led to the conclusion that objects can be automatically detected with CNR analysis and that our current system has a spatial resolution limit near 4 mm and a contrast resolution limit near 1.4. A new linear convolution method of CNR calculation was developed for automated region of interest (ROI) detection.

Artifacts↗
PubMedDate not supplied

Accuracy of objective ambulatory accelerometry in detecting motor complications in patients with Parkinson disease.

Shortcomings of existing assessment methods in Parkinson disease (PD) have led to the development of continuous ambulatory multichannel accelerometry for the assessment of the core features of PD. Although measures for hypokinesia, bradykinesia, and tremor have been validated in groups of patients with PD, it is unclear whether this method is able to detect "on" with or without dyskinesias, and "off" in individual PD patients. This study therefore addressed the accuracy of objective ambulatory accelerometry in detecting motor complications in 15 PD patients, using a self-assessment scale as gold standard. Measures for hypokinesia, bradykinesia, and tremor showed limited sensitivity (0.60-0.71) and specificity (0.66-0.76) for motor complications in individual PD patients. In the group of PD patients, comparing the "on" with the "off" state yielded statistically significant differences for tremor only. Objective dyskinesia measures correlated with time spent with dyskinesias (r = 0.89). Although validated for the measurement of hypokinesia, bradykinesia, and tremor, continuous ambulatory multichannel accelerometry currently cannot detect "on" and "off" in individual PD patients.

Aged↗
PubMed2004

Radical retropubic prostatectomy in men younger than 45 years diagnosed during early prostate cancer detection program.

OBJECTIVES: To evaluate the incidence and outcome of prostate cancer in men younger than 45 years of age treated with radical retropubic prostatectomy after screening in an early prostate cancer detection program. METHODS: Our study group comprised 19,302 men younger than 45 years old who participated in this program. The indications for prostate biopsy were a prostate-specific antigen (PSA) level of 1.25 ng/mL or greater and a percent-free PSA value of 18% or less. Patients with prostate cancer underwent nerve-sparing radical retropubic prostatectomy. Intraoperative and early postoperative complications, clinical and pathologic stage, Gleason score, and surgical margins were reviewed retrospectively. In addition, potency, continence, and biochemical recurrence were assessed at the last follow-up visit. RESULTS: Of the study population eligible for prostate biopsy (1027 patients), only 175 (17%) consented to undergo the procedure (mean PSA 3.8 ng/mL). Twenty-eight men were diagnosed with prostate cancer, corresponding to 0.14% of the screened population and 16% of the biopsied patients. Twenty-six patients agreed to undergo radical retropubic prostatectomy. Pathologic examination revealed organ-confined disease in 22 (84.6%) and extraprostatic extension in 4 (15.4%). Positive surgical margins were seen in 2 patients (7.7%). The Gleason score was 7 or greater in 11 (42.3%) and 6 or less in 15 patients (57.7%). During a mean follow-up period of 15.8 months (range 3 to 36), all patients were continent, and 13 of the 16 patients with a follow-up of 12 months or longer were potent. CONCLUSIONS: In a large screening population younger than 45 years old, 16% of biopsied patients were positive for prostate cancer. These tumors were clinically significant but of a low stage and therefore potentially curable by surgery.

Adenocarcinoma↗
PubMed1998

Attentional biases in eating disorders: a visual probe detection procedure.

OBJECTIVE: To investigate attentional biases for body shape and weight-related stimulus words among subjects with anorexia nervosa, bulimia nervosa, and control subjects classified using a measure of dietary restraint. METHODS: A visual probe detection task was used to assess attention toward stimulus words reflecting either a thin or a large physique and positively or negatively valenced emotion words. RESULTS: In comparison to controls, subjects with eating disorders detected target probes more slowly when they appeared in the same location as had stimulus words connoting a thin physique. In addition, there was a trend toward faster detection or target probes that appeared in the same location as had stimulus words connoting a large physique. Neither of these effects were observed among restrained eaters. DISCUSSION: Our results extend prior work suggesting information-processing biases for body shape and weight-related stimuli among persons with eating disorders.

Adult↗
PubMedDate not supplied

Increased natural killer cells in fluids. A new, sensitive means of detecting carcinoma.

OBJECTIVE: Natural killer (NK) cells are cells of undefined lineage that are capable of lysing certain tumor cell lines in vitro. Determination of NK cell percent (NK%) in effusions by flow cytometry could aid in the detection of malignancies. STUDY DESIGN: Over a six-month period at the Houston Veterans Affairs Medical Center, fresh effusions were routinely processed for cytology, and a portion was submitted for lymphocyte immunophenotyping using the FACScan and a panel including CD16/CD56 for NK cells. Seventy fluids (42 pleural, 28 peritoneal) from 62 men were examined. RESULTS: NK cell percents were markedly increased in 15 cases (29-68%, mean 45.5) and low in 55 (2-20%, mean 8). Fourteen of the 15 cases with increased NK% were positive for carcinoma (93%), while 54/55 cases with low ones were negative for carcinoma (98%). Mesotheliomas, lymphomas and leukemias had low NK%. CONCLUSION: Using the Mann-Whitney U test, an increase in NK% predicts metastatic carcinoma with a P level of < .00001.

Adult↗
PubMed1992

Screening test for detection of metallic foreign objects in the orbit before magnetic resonance imaging.

RATIONALE AND OBJECTIVES: A study was designed to determine whether plain films, used as a screening modality for magnetic resonance imaging (MRI), could reliably detect intraorbital metallic foreign objects. METHODS: In the first experiment, 20 metal particles were placed in five human cadaver orbits. Routine orbital plain film series and computed tomography (CT) were obtained, randomized, and interpreted blinded by three experienced radiologists. RESULTS: The threshold size of particle detection for CT (0.07 mm3) was lower than for plain films (0.12 mm3). Placing metal particles in artificial and true vitreous demonstrated that all particles moved under a magnetic field at 1.5 T. When human globes were exposed to industrial tools (grinder, bandsaw, air hose, etc.), no metal objects penetrated the sclera. CONCLUSIONS: Plain films can be used as a low-cost, low-radiation screening procedure for high-risk patients with occupations involving metal work. CT should be used for patients with a history of eye trauma from other causes.

Costs and Cost Analysis↗
PubMed2002

Temporal resolution in young and elderly subjects as measured by mismatch negativity and a psychoacoustic gap detection task.

OBJECTIVES: The speech understanding difficulties of elderly persons with age-related hearing loss may be related in part to reduced auditory temporal resolution. To investigate the effects of aging on temporal resolution, the electrophysiological and psychoacoustic detection thresholds for a very short silent gap within a pure tone were determined, and the relation between the two test results was examined. METHODS: Behavioral gap detection thresholds were determined in 10 young and 10 elderly normally hearing subjects using an adaptive test procedure. To elicit mismatch negativity (MMN), deviant stimuli with gap durations varying from 6 to 24 ms in 3 ms steps were presented in separate test blocks. RESULTS: There were no significant differences in the psychoacoustic gap detection thresholds between young and elderly subjects. In contrast, longer gaps were needed to elicit MMN in elderly subjects. They also had significantly reduced MMN peak amplitudes, increased MMN peak latencies, a significantly smaller P2 amplitude and longer P2 latency in their responses to the standard stimulus when compared to the same measures in young subjects. CONCLUSIONS: Processing of basic temporal stimulus features in elderly subjects is considerably more reduced at the preattentive level (as indicated by MMN), than when attention is directed to the task (as indicated by the psychoacoustic results).

Acoustic Stimulation↗
PubMed1992

Photo-ablation of single neurons in the fly visual system reveals neural circuit for the detection of small moving objects.

Many animals use relative motion to segregate objects from their background. Nerve cells tuned to this visual cue have been found in various animal groups, such as insects, amphibians, birds and mammals. Well examined examples are the figure detection (FD) cells in the visual system of the blowfly. The mechanism that tunes a particular FD-cell, the FD1-cell, to small-field motion is analyzed by injecting individual visual interneurons with a fluorescent dye and ablating them by illumination with a laser beam. In this way, it is shown that the FD1-cell acquires its specific spatial tuning by inhibitory input from an identified GABAergic cell, the ventral centrifugal horizontal (VCH)-cell which is most sensitive to coherent large-field motion in front of both eyes. For the first time, the detection of small objects by evaluation of their motion parallax, thus, can be attributed to synaptic interactions between identified neurons.

Animals↗
PubMed2003

Detecting changes between real-world objects using spatiochromatic filters.

A behavioral and computational treatment of change detection is reported. The behavioral task was to judge whether a single object substitution change occurred between two "flickering" 9-object scenes. Detection performance was found to vary with the similarity of the changing objects; object changes violating orientation and category yielded the fastest and most accurate detection responses. To account for these data, the BOLAR model was developed, which uses color, orientation, and scale selective filters to compute the visual dissimilarity between the pre- and postchange objects from the behavioral study. Relating the magnitude of the BOLAR difference signals to change detection performance revealed that object pairs estimated as visually least similar were the same object pairs most easily detected by observers. The BOLAR model advances change detection theory by (1) demonstrating that the visual similarity between the change patterns can account for much of the variability in change detection behavior, and (2) providing a computational technique for quantifying these visual similarity relationships for real-world objects.

Color Perception↗