Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “object detection”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,243 records · Page 69Linked to original sources
PubMed2005

Temporal case clustering in pityriasis rosea: a regression analysis on 1379 patients in Minnesota, kuwait, and diyarbakir, Turkey.

OBJECTIVE: To detect temporal case clustering in patients with pityriasis rosea in different geographic locations. DESIGN: Regression analysis of dates on which 1379 patients were diagnosed as having pityriasis rosea in 3 different geographic locations. The control data consisted of dates of diagnosis of patients with psoriasis in the same settings. SETTING: Dermatology clinics in Kuwait, Minnesota, and Diyarbakir, Turkey.Patients Patients with pityriasis rosea and psoriasis seeking care in the clinics. RESULTS: Three significant positive clusters (P = .005, P =.001, and P =.01, respectively) and 1 significant negative cluster (P<.001) were detected in these series of patients. No cluster was detected in 2 corresponding series of patients with psoriasis in Kuwait and Turkey. CONCLUSION: Temporal case clustering exists in pityriasis rosea.

Adolescent↗
PubMedDate not supplied

Thyroid nodules in Graves disease and the risk of thyroid carcinoma.

BACKGROUND: The risk of thyroid carcinoma in patients with Graves disease has been particularly emphasized when nodules coexist with thyroid hyperplasia; a surgical approach has been suggested. OBJECTIVES: To detect thyroid nodules early in patients with Graves disease and to evaluate the risk of carcinoma. METHODS: The study group included 315 consecutive outpatients with Graves hyperthyroidism not previously treated with surgery or radioiodine therapy. Thyroid ultrasonography was performed at the time of enrollment and repeated annually in all patients; fine-needle aspiration (FNA) was carried out in those patients with nodules and repeated after 2 years or at shorter intervals. RESULTS: One hundred six of 315 patients with Graves disease had thyroid nodules 8 mm in diameter or larger detected by ultrasonography. In 49 patients, nodules were present at the time of the first examination; in 57 patients, nodules developed during follow-up. Fine-needle aspiration cytology results revealed features of carcinoma in only 1 patient; this was confirmed by histologic examination of excised thyroid tissue. The nodules with normal cytologic features at the time of the first examination did not show any clinical and/or cytologic evolution toward malignancy during follow-up. CONCLUSIONS: Ultrasonographic evidence of nodules was frequently found among our patients with Graves disease, but malignant FNA cytologic findings of the examined nodules were rare at the time of diagnosis and throughout the course of the disease. When FNA cytologic evaluation does not indicate malignancy, the presence of thyroid nodules in patients with Graves disease does not indicate an aggressive therapeutic approach.

Adult↗
PubMedDate not supplied

Atrophic body gastritis in patients with autoimmune thyroid disease: an underdiagnosed association.

BACKGROUND: Atrophic body gastritis (ABG) has never been histologically characterized in patients with autoimmune thyroid disease (AITD), and its prevalence may be substantially different from that previously assessed based on only indirect evidence. OBJECTIVE: To detect and characterize the presence of ABG in patients with AITD. METHODS: Sixty-two patients with AITD (5 men and 57 women), aged between 21 and 74 years, have been screened for the presence of ABG by assaying serum gastrin levels. Patients with hypergastrinemia underwent gastroscopy followed by the histological examination of multiple biopsy specimens. The diagnosis of ABG was based on hypergastrinemia and pentagastrin-resistent achlorhydria, confirmed by histological examination. RESULTS: Twenty-two (35%) of 62 patients had hypergastrinemia (mean +/- SEM gastrin level, 1070+/-288 pmol/L). The diagnosis of ABG has been histologically confirmed in all 22 patients, and the score of atrophy was moderate to severe. In group A (patients aged 20-40 years; n = 21), 6 patients (29%) had ABG, compared with 11 patients (37%) in group B (patients aged 41-60 years; n = 30) and 5 patients (45%) in group C (patients aged 61-80 years; n = 11). Antiparietal cell antibodies were detected in only 68% (15/22) of patients with ABG. Anemia was observed in 82% (18/ 22) of patients with AITD and ABG but only in 22% (9/40) of patients without ABG (P<.0001). CONCLUSIONS: In the patients with AITD studied, about one third had ABG, which was diagnosed also in young patients; the measurement of gastrin levels represented the most reliable tool in the diagnosis of ABG; and the presence of anemia, even microcytic, was suggestive of undiagnosed ABG.

Achlorhydria↗
PubMed2006

Brain white matter impairment in congenital adrenal hyperplasia.

BACKGROUND: Congenital adrenal hyperplasia (CAH) is an inherited recessive disorder of adrenal steroidogenesis. Past reports suggested that brain white matter could be involved in CAH. OBJECTIVE: To detect the presence, and possible changes over time, of brain white matter abnormalities in patients with CAH. DESIGN: Neurological examination and brain magnetic resonance imaging (MRI) that were repeated in 12 patients after a mean interval of 11 years. SETTING: Pavia, northern Italy. Patients Twenty-two patients with CAH. MAIN OUTCOME MEASURES: Evaluation of clinical neurological findings and brain MRI T2-weighted images. RESULTS: Ten (45%) of 22 patients with CAH had white matter abnormalities (diffuse in 4 cases, focal in 3 cases, and both diffuse and focal in 3 cases) on MRI. The MRI findings never changed over repeated assessments. CONCLUSIONS: Subclinical brain white matter involvement is frequent in CAH. This might be due to hormonal imbalance during brain development or corticosteroid treatments. Our study findings indicate that a relationship with demyelinating diseases can also be suggested. Diagnosis of CAH should be suspected in young subjects with brain MRI white matter abnormalities that are not otherwise explicable.

Adolescent↗
PubMed2002

Free radicals in phacoemulsification and aspiration procedures.

OBJECTIVES: To detect free radicals in phacoemulsification and aspiration procedures using electron-spin resonance and to observe the effect of ophthalmic viscosurgical devices (viscoelastic agents) on free radical intensity. METHODS: (1) A test tube containing BSS Plus (Alcon Laboratories, Inc, Fort Worth, Tex) with 1% of the spin-trapping agent, 5,5'-dimethyl-1-pyrroline N-oxide, without irrigation and aspiration, was exposed to ultrasound (100% for 20 seconds). A preparation of hyaluronate sodium (Healon [a cohesive agent that contains 1% hyaluronate sodium] (Pharmacia, Uppsala, Sweden) or Viscoat [a dispersive agent that contains 3% hyaluronate sodium and 4% chondroitin sulfate] (Alcon Laboratories, Inc)) was added to the solution to observe inhibitory effects. (2) To simulate a clinical procedure, an eye model with irrigation and aspiration of a combination of 1% 5,5'-dimethyl-1-pyrroline N-oxide and BSS Plus, 25 mL/min, as the irrigating solution was exposed to ultrasound (for 10, 20, or 30 seconds). Healon or Viscoat was injected into the anterior chamber. Free radicals were measured by an electron-spin resonance spectrometer. RESULTS: (1) A characteristic signal corresponding to hydroxyl radicals was detected. Similar inhibition by Healon and Viscoat was observed. (2) Two ophthalmic viscosurgical devices similarly suppressed the signal at 10 seconds. The inhibition by Healon ceased at 20 seconds, whereas Viscoat suppressed the signal throughout the time course. CONCLUSIONS: Phacoemulsification produces hydroxyl radicals in the anterior chamber even with irrigation and aspiration. The effect of ophthalmic viscosurgical devices on free radicals depends on the retention of the materials within the anterior chamber. CLINICAL RELEVANCE: There are complications associated with phacoemulsification.

Anterior Chamber↗
PubMed1994

Risk factors for the development of glaucomatous visual field loss in ocular hypertension.

OBJECTIVE: To detect characteristics of persons with ocular hypertension that are associated with a higher risk of future glaucomatous field loss. METHODS: Annual examinations of the optic disc, nerve fiber layer, and visual field in 647 persons with bilateral intraocular pressure higher than 21 mmHg and initially normal visual field test results with the Goldmann perimeter. RESULTS: Sixty-eight persons developed a field defect on two consecutive Goldmann visual field tests in at least one eye, while 579 others retained normal fields. Moderate or severe nerve fiber layer atrophy at baseline was associated with a seven to eight times greater risk of development of visual field loss. Attributes that were significantly associated with the incidence of field loss included older age, larger cup-disc ratio, smaller rim-disc area ratio, larger cup asymmetry, presence of disc crescent, and higher intraocular pressure. Characteristics found not to be associated with incidence were gender, race, hypertension, diabetes, refractive error, family history of glaucoma, smoking or alcohol drinking history, and disc area. CONCLUSIONS: Increasing nerve fiber layer atrophy judged by a semiquantitative grading system was associated with increasing risk of development of visual field loss among persons with ocular hypertension. The relationship of the development of field loss to race, myopia, family history of glaucoma, and medical history are more complex than has been presumed.

Adult↗
PubMed1998

Early-onset sensorineural hearing loss and late-onset neurologic complaints caused by a mitochondrial mutation at position 7472.

OBJECTIVES: To detect a mitochondrial mutation responsible for maternally transmitted hearing loss with late-onset neurologic features in a 3-generation Dutch family, and to describe the hearing loss, associated symptoms, and vestibular dysfunction. PATIENTS AND METHODS: All maternally related family members (n = 69) were investigated using standard audiometry. In a selected group, vestibulo-ocular examinations and additional neurologic and ophthalmologic examinations were performed. Twenty milliliters of venous blood was taken from all participants for genetic studies. SETTING: University medical center. RESULTS: All maternally related individuals carried an extra C at position 7472 of the mitochondrial genome. Hearing loss was the only symptom or presenting symptom in most family members and most pronounced at higher frequencies. Hearing loss at lower frequencies was demonstrated in individuals 10 years and older. Most patients had vestibular hyperreactivity and were susceptible to motion sickness, suggesting vestibulocerebellar dysfunction. Neurologic complaints were infrequent and presented by older individuals; however, numerous enlarged mitochondria were found in a muscle biopsy specimen of an individual with hearing impairment but without neurologic symptoms. CONCLUSIONS: Respiratory chain dysfunction should be considered as a possible cause of progressive sensorineural hearing loss. More research into the causes of high-frequency impairment should be considered, especially when sensorineural hearing loss, syndromal or nonsyndromal, is exclusively maternally transmitted. Maternal transmission of hearing impairment can also be valuable in the diagnosis of unclear neurologic syndromes.

Adolescent↗
PubMed2004

Intraoperative molecular margin analysis in head and neck cancer.

BACKGROUND: Tumor-specific molecular alterations in surgical margins have been shown to predict risk of local recurrence. However, assays used for these analyses are time-consuming and therefore cannot be used in the intraoperative setting. OBJECTIVE: To detect and quantify tumor-specific methylated promoter sequences in surgical margins in a time frame suitable for intraoperative use. DESIGN: A novel quantitative methylation-specific polymerase chain reaction (QMSP) protocol. METHODS: A total of 13 patients with head and neck squamous cell carcinoma (HNSCC) were initially characterized for molecular alterations in their tumor at the time of biopsy. Six primary tumors were found to harbor promoter hypermethylation for p16 and O6-methylguanine-DNA-methyltransferase (MGMT) genes. Rapid QMSP was then used to identify promoter hypermethylation of these genes in the surgical margins. Results were compared with standard intraoperative histologic frozen section analysis and with conventional QMSP. RESULTS: Using our rapid QMSP assay, we found that 3 patients had methylation-positive margins. Tumor margins from 2 patients were methylated for p16 alone, and margins from 1 patient were methylated for p16 and MGMT simultaneously. Molecular margin analysis was completed in less than 5 hours, a time frame appropriate for selected major HNSCC resections that require combined primary tumor resection, cervical lymphadenectomy, and complex reconstruction. This technique was comparable in sensitivity to conventional QMSP. CONCLUSION: Rapid molecular margin analysis using QMSP is feasible and may be performed intraoperatively in selected patients with HNSCC that requires extensive resection.

Carcinoma, Squamous Cell↗
PubMed1996

Increased epithelial cell proliferation in nasal polyps.

OBJECTIVE: To detect, quantify, and compare respiratory epithelial cell proliferation in nasal mucosa and polyps from patients with nasal polyposis. DESIGN: Cohort study. SETTING: Patients and samples were selected at the Hôpital Intercommunal de Créteil (France). Flow cytofluorometry and immunohistochemistry were performed at Hôpitaux Tenon and Mondor (Université Paris [France] VI et XII). PATIENTS: Twenty-one patients undergoing endoscopic ethmoidectomy for treatment of nasal polyposis. METHODS: In 10 cases, epithelial cells were removed from frozen inferior turbinate mucosa and polyps by mechanical disaggregation and were then analyzed by flow cytofluorometry, providing the cell DNA content (propidium iodide labeling) and the percentage of S-phase cells. In 11 cases, inferior turbinate mucosa and polyps were fixed in formaldehyde and embedded in paraffin. Proliferating cell nuclear antigen expression in the epithelium was quantified by immunohistochemistry; a proliferating cell nuclear antigen index was calculated for each sample in the basal area, suprabasal area, and full height of the epithelium. RESULTS: All cell populations studied were diploid, and percentages of S-phrase cells were significantly higher in nasal polyps than in mucosa. Proliferating cell nuclear antigen indexes were significantly higher in nasal polyps than in the suprabasal area and full height of the mucosal epithelium. CONCLUSION: Cell proliferation is increased in epithelium from nasal polyps. Epithelial damage caused by inflammatory mediators could induce this increased cell proliferation via epithelial repair processes. Inflammatory cells could up-regulate epithelial cell proliferation by secreting growth factors.

Cell Division↗
PubMed1999

V2 regions of 16S ribosomal RNA used as a molecular marker for the species identification of streptococci in peripheral blood and synovial fluid from patients with psoriatic arthritis.

OBJECTIVE: To detect the 16S ribosomal RNA (rRNA) of 3 streptococcal species in the peripheral blood and synovial fluid of patients with psoriatic arthritis (PsA). METHODS: Reverse transcription-polymerase chain reaction (RT-PCR) detection targets bacterial 16S rRNA, which is present in bacteria at high copy numbers. The 3 species-specific primers for group A streptococci (GAS; Streptococcus pyogenes), group B streptococci (GBS; Streptococcus agalactiae), and Streptococcus pneumoniae were designed from the fragments of highly variable V2 regions of 16S rRNA. Total RNA was prepared from whole peripheral blood and joint fluid obtained from patients with PsA and rheumatoid arthritis (RA). All positive PCR reactions were then sequenced with a Pharmacia ALF DNA sequencing system. RESULTS: Our data in 19 PsA patients showed that 7 peripheral blood samples were positive for GAS (P = 0.006 versus GAS-positive RA patients [n = 0], by Fisher's exact test), and 2 were also positive for GBS. One synovial fluid sample from a PsA patient was positive for GAS. S pneumoniae was absent from all specimens. Seventeen patients with RA were PCR negative for the 3 streptococcal species. Peripheral blood from a patient with inflammatory bowel disease was positive for GAS. CONCLUSION: The presence of GAS 16S rRNA in the peripheral blood and synovial fluid of patients with PsA supports the concept that PsA is a reactive arthritis to certain streptococci.

Arthritis, Psoriatic↗
PubMed2006

A mutation in the GABA(A) receptor alpha(1)-subunit is associated with absence epilepsy.

OBJECTIVE: To detect mutations in GABRA1 in idiopathic generalized epilepsy. METHODS: GABRA1 was sequenced in 98 unrelated idiopathic generalized epilepsy patients. Patch clamping and confocal imaging was performed in transfected mammalian cells. RESULTS: We identified the first GABRA1 mutation in a patient with childhood absence epilepsy. Functional studies showed no detectable GABA-evoked currents for the mutant, truncated receptor, which was not integrated into the surface membrane. INTERPRETATION: We conclude that this de novo mutation can contribute to the cause of "sporadic" childhood absence epilepsy by a loss of function and haploinsufficiency of the GABA(A) receptor alpha(1)-subunit, and that GABRA1 mutations rarely are associated with idiopathic generalized epilepsy.

Adolescent↗
PubMed1997

Expression of membrane type 1 matrix metalloproteinase in human articular cartilage.

OBJECTIVE: To detect the message for membrane type 1 (MT1) matrix metalloproteinase (MMP) in articular cartilage and chondrosarcoma cells, to study its expression in osteoarthritis (OA), and to determine whether interleukin-1beta (IL-1beta) influences its expression. METHODS: Reverse transcription-polymerase chain reaction methods were used to detect message. Cloning and sequencing were applied to confirm the sequence. Northern blotting was used to quantify the message for MT1-MMP and to compare its expression in OA cartilage with or without IL-1beta treatment. In situ hybridization was utilized to show MT1-MMP transcripts in cartilage and to study the influence of IL-1beta. RESULTS: The results show that MT1-MMP messenger RNA (mRNA) is expressed in chondrosarcoma cells and OA chondrocytes. Results of the in situ hybridization confirmed the expression in OA cartilage as well as in normal cartilage. The level of mRNA was not modulated following IL-1beta stimulation. CONCLUSION: This study shows that MT1-MMP is expressed by chondrocytes. The similarities in mRNA levels in OA and normal chondrocytes suggest that regulation of MT1-MMP mRNA may not be a primary factor in OA.

Blotting, Northern↗
PubMed2004

Autoreactive CD8+ cytotoxic T lymphocytes to major histocompatibility complex class I chain-related gene A in patients with Behçet's disease.

OBJECTIVE: To detect and characterize the autoreactive CD8+ T cells to major histocompatibility complex class I chain-related gene A (MICA), a stress-inducible antigen preferentially expressed on the epithelium and endothelium, in patients with Behcet's disease (BD). METHODS: A candidate for the antigenic MICA peptide was selected based on its predicted binding affinity for HLA-B51 and proteasomal cleavage sites. Peripheral blood T cells from 14 patients with BD and 15 healthy controls were repeatedly stimulated with the MICA peptide, and the specific T cell response was measured by peptide-induced interferon-gamma. Cytotoxic T lymphocyte activity was examined by chromium-51 release from an HLA-B51-transfected B cell line in the presence of the MICA peptide. RESULTS: A 9-mer peptide AAAAAIFVI (termed MICA transmembrane [MICA-TM]) was selected as a candidate for the antigenic peptide presented by HLA-B51. A specific T cell response to MICA-TM was detected in 4 patients with BD (29%) but in none of the 15 healthy donors. All 4 responders had HLA-B51 and active disease, and the specific T cell response was lost after the BD-related symptoms disappeared. The MICA-induced T cell response was specifically inhibited by anti-HLA class I antibody or by CD8+ cell depletion. MICA-reactive T cells recognized an HLA-B51-transfected B cell line pulsed with MICA-TM or a B cell line transfected with both HLA-B51 and MICA in the absence of exogenous peptides. Finally, MICA-stimulated T cell lines lysed the HLA-B51-expressing B cell line in the presence of MICA-TM. CONCLUSION: HLA-B51-restricted cytotoxic T lymphocytes autoreactive to MICA may be involved in the pathogenesis of BD.

Autoimmunity↗
PubMed2006

Distinguishing adenoid cystic carcinoma from cylindromatous adenomas in salivary fine-needle aspirates: the cytologic clues and their ultrastructural basis.

The utilization of fine-needle aspiration (FNA) biopsy in salivary tumors is hindered by the reluctance of many cytopathologists to report adenoid cystic carcinoma (ACC) because its cylindromatous stroma is observed occasionally in pleomorphic adenoma (PA) and basal cell adenoma (BA), and a diagnosis of ACC results in radical surgery. The aim of this study is to identify dependable features to distinguish the look-alike entities and illustrate their ultrastructural base. We compared 20 cases of ACC to 15 cases of cylindromatous PA and 9 cases of BA. All were direct smears stained with Diff-Quik, hematoxylin and eosin, Papanicolaou, or Ultrafast Papanicolaou (UFP) stain. In addition to the presence of cylindromatous pattern, the amount of cytoplasm in the neoplastic cells and nuclear features were compared. Tissue was dissected from paraffin blocks and processed for electron microscopy in selected cases. The difference in nuclear features can be distinguished in UFP-stained smears and electron microscopy. The nuclei of ACCs were heterochromatic with coarse chromatin and irregular nucleoli, whereas the nuclei of PAs were euchromatic with fine chromatin and small compact nucleoli. The nuclei of BAs were hyperchromatic but finely textured. The cytoplasm of PAs was detectable with every stain at 40x objective, but the cytoplasm of BAs required UFP stain and 100x objective to be detected. The cytoplasm of majority of neoplastic cells of ACCs are invisible, because the thin rim of cytoplasm measured <1 microm ultrastructurally, well beyond the resolution of a light microscope. Rare cohesive fragment of epithelial cells in ACC have scanty blue cytoplasm in UFP stain and can be recognized as ductal cells. In conclusion, in our analysis of salivary tumors with a cylindromatous pattern, the seemingly naked nuclei of neoplastic cells with their coarse nuclear chromatin and irregular nucleoli, as revealed by the UFP stain, reliably distinguished ACC from cylindromatous adenomas.

Adenoma↗
PubMed2002

Confusion assessment method in the diagnostics of delirium among aged hospital patients: would it serve better in screening than as a diagnostic instrument?

BACKGROUND: The Confusion Assessment Method (CAM) is an easy, four-step algorithmic diagnostic test developed to detect delirium. OBJECTIVE: To determine how sensitive and specific the CAM is in diagnosing delirium when compared with fully operationalized criteria of delirium according to the Diagnostic and Statistical Manual of Mental Disorders (DSM) editions III, III revised, and IV, and the International Classification of Diseases (ICD) 10th edition. METHODS: A cross-sectional study with blinded assessments was performed on consecutive elderly patients (>70 years) (n=81) in two acute geriatric hospitals in Helsinki, Finland. The sensitivity, specificity, likelihood ratios, and positive and negative predictive values of CAM were assessed with the DSM-III, DSM-III-R, DSM-IV, and ICD-10 criteria of delirium used as reference standards. RESULTS: Sensitivity rates of the CAM were proved to be only moderate (0.81-0.86) against all formal criteria of delirium. The specificity rates were lower (0.63-0.84), and far less than reported in previous studies using global assessment of the reference standard. Instead of the DSM-III-R, from which it is derived, the CAM seems more concordant with the DSM-IV criteria of delirium. The likelihood ratio for a positive CAM test was 5.06 and for a negative test 0.23, when compared with the DSM-IV. CONCLUSION: The CAM seems to be an acceptable screening instrument for delirium, but the diagnosis should be ensured according to the formal criteria of delirium, preferably by the DSM-IV.

Aged↗
PubMed2006

Characteristics associated with discharge to home following prolonged mechanical ventilation: a signal detection analysis.

The objective of study was to identify characteristics associated with being home at 6 months in 80 patients on prolonged mechanical ventilation (PMV) (> or =7 days). At 6 months, 47.5% were home, 13.8% institutionalized, and 38.8% deceased and classified "not home." Using signal detection methodology (SDM), four mutually exclusive groups at high and low probability of being home were identified. The best outcome (94.4% home) was achieved by patients with an admission Charlson Comorbidity Score < or =3 and an Acute Physiology Score (APS) < or =21 and the worst outcome (23.4% home) by patients with an admission Charlson Comorbidity Score >3 and Health Assessment Questionnaire score >2.7. SDM provided an effective means of identifying subgroups likely to be discharged home using available information.

Activities of Daily Living↗
PubMed2005

Fetal lateral neck cysts: the significance of associated findings.

OBJECTIVES: The detection of fetal lateral neck cysts (FLNC) may create anxiety and confusion among pregnant woman and their physicians. We attempted to determine the incidence and significance of FLNC. Also, we tried to define the importance of the associated findings: the laterality of the finding, triple test results, maternal age and other ultrasonographic findings. METHODS AND MATERIALS: Between January 2000 and September 2003, 80 fetuses were evaluated at our institution for FLNC out of 3350 ultrasonic scans done for fetal malformations at 14-16 weeks' gestation. RESULTS: The incidence of FLNC was 2.4% (80/3350). The majority of cases were isolated (53/80, 66%) and unilateral (46/80, 58%). Down syndrome was associated with nonisolated FLNC. CONCLUSION: Whether the finding was unilateral or bilateral had no significance. Associated increased nuchal translucency (NT) was of importance. Furthermore, the sole finding of increased NT is significant and the finding of the FLNC has no added value. There was no correlation between isolated FLNC without NT and fetal aneuploidy. However, other risk factors increase the risk for aneuploidy by up to 15 fold.

Adult↗
PubMed2005

Rapid determination of trisomy 21 from amniotic fluid cells using single-nucleotide polymorphic loci.

OBJECTIVES: Rapid detection of trisomy 21 is an important goal for prenatal genetic centers. Fluorescent-PCR and DNA fragment analysis was developed a decade ago and thousands of samples were analyzed in routine practice using this method. Quantitative real-time PCR with melting curve analysis using SNP markers for trisomy 21 detection was described recently. We studied the reliability of this method on a cohort of samples of Hungarian patients. METHODS: DNA was isolated with silica adsorption method from amniotic fluid cells. We investigated 67 trisomy 21 and 62 diploid samples in the study. Quantitative real-time PCR was performed using hybridization probes combined with melting curve analysis. Peak areas under the derivative curves were determined and analyzed. RESULTS: The SNP marker WIAF 899 was informative in 41.86% of cases and WIAF 2643 in 48.83%. The melting curve area ratios were significantly different between trisomic and normal cases for WIAF 899 (trisomic 0.5246 +/- 0.2498 vs 0.8347 +/- 0.5234; p < 0.001), while in the case of WIAF 2643, they were not different. CONCLUSION: Combined and selected SNP markers could be valuable tools for rapid trisomy 21 detection in prenatal genetic screening.

Alleles↗