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At least 937 records · Page 52Linked to original sources
PubMed2005

[Detection of glucocorticoid receptor-alpha mRNA expression using FQ-RT-PCR in nasal polyp].

OBJECTIVE: To detect the expression of the glucocorticoid receptor-alpha (GR-alpha) mRNA in nasal polyp and normal nasal mucosa and investigate the significance of GR-alpha in progression of nasal polyp. METHOD: The expression of GR-alpha mRNA in 36 samples of nasal polyp and 31 samples of normal nasal mucosa was examined by using fluorescent quantitative PCR(FQ RT-PCR). RESULT: The GR-alpha mRNA levels in normal nasal mucosa [(135.4 +/- 5.2) x 10(10) copy/g] were significantly higher than those in nasal polyp [(25.5 +/- 5.0) x 10(10) copy/g] (P < 0.01). CONCLUSION: The low expression of GR-alpha mRNA in nasal polyp is related to the progression of nasal polyp.

Adult↗
PubMed1991

Accuracy of precordial percussion in detecting cardiomegaly.

STUDY OBJECTIVE: To assess the value of precordial percussion in detecting cardiomegaly, and to compare it with palpation of the apical impulse. DESIGN: Descriptive study. SETTING: Hospitals and clinics of a university medical center. PATIENTS: Light indirect percussion of the precordium was performed on 72 inpatients and 28 outpatients. All patients had a posteroanterior radiograph of the chest. Percussors were unaware of the clinical history and of chest roentgenogram results. MEASUREMENTS AND MAIN RESULTS: Thirty-six patients (36%) had cardiomegaly, defined as a cardiothoracic ratio of greater than 0.5 on chest roentgenogram. The cardiothoracic ratio was significantly correlated with percussion distance from the midsternal line in the left fourth (r = 0.35, p less than 0.0006), fifth (r = 0.65, p less than 0.00001), and sixth (r = 0.40, p less than 0.0001) intercostal spaces. After adjustment for clinical symptoms and systolic and diastolic blood pressures, percussion distance in the left fifth intercostal space remained a significant independent predictor of the cardiothoracic ratio. Percussion distance in the left fifth interspace discriminated cardiomegaly with a receiver-operating characteristic (ROC) area of 0.95. Percussion dullness more than 10.5 cm from the midsternal line in the left fifth interspace had a sensitivity of 94.4% (95% confidence interval [CI], 79.9% to 99.0%) and a specificity of 67.2% (CI, 54.2% to 78.1%). Distance of the apical impulse from the midsternal line discriminated with an ROC area of 0.95, but an impulse was palpated in only 40% of cases. CONCLUSIONS: Percussion in the left fifth intercostal space accurately discriminates patients with and without cardiomegaly, and adds information beyond that obtainable from the history and other parts of the physical examination.

Adolescent↗
PubMed1999

Ultrasound detection of pneumothorax.

OBJECTIVE: To determine the accuracy of ultrasound in the detection of pneumothorax. METHODS: Prospective blinded study comparing ultrasound, CT and radiographic findings in 29 patients following 41 CT-guided lung biopsies. Ultrasound examination of the chest was limited to the biopsy needle entry site. RESULTS: Thirteen patients developed a post-biopsy pneumothorax demonstrated by CT. Seven of these were detected by ultrasound and six were visible on erect chest radiographs. Six of the 13 pneumothoraces were not detected by ultrasound, but five of these were loculated away from the biopsy needle entry site and were therefore in areas not examined during the limited ultrasound examination. There were no false-positive diagnoses of pneumothorax using ultrasound. The positive predictive value for ultrasound was 100% and the negative predictive value was 82%. CONCLUSION: In this patient group, ultrasound was more sensitive than erect chest radiography in the detection of pneumothorax. Both have a specificity of 100%. This study suggests that ultrasound may prove valuable in pneumothorax detection when rapid conventional radiography is not possible or practical, and in circumstances where ultrasound is readily available, such as during ultrasound-guided interventional procedures.

Biopsy, Needle↗
PubMed1998

Accuracy of auscultation in the detection of haemopneumothorax.

OBJECTIVE: To assess the accuracy of auscultation in the detection of haemopneumothorax. DESIGN: Prospective study. SETTING: University hospital, Taiwan. PATIENTS: 148 patients with chest injuries admitted between July 1994 and August 1996. MAIN OUTCOME MEASURES: Correlation between the results of auscultation and radiographic findings in 148 patients with injuries to the chest. 83 (56%) had internal injuries, of whom 38 had pneumothoraces, 24 haemothoraces, and 21 haemopneumothoraces. RESULTS: Auscultation had a sensitivity of 84%, a specificity of 97%, an accuracy of 89% and a positive predictive value of 97% in the detection of these injuries. CONCLUSIONS: Auscultation is not as accurate as chest radiography. Chest tubes can be inserted before chest radiography in patients in whom auscultation has indicated an injury. A chest radiograph is essential in those patients with normal breath sounds to exclude a haemopneumothorax that had been missed by auscultation.

Adolescent↗
PubMed1997

Accuracy of prenatal sonography for detecting circumvallate placenta.

OBJECTIVE: We determined the accuracy of prenatal sonography for detecting placental circumvallation, a placental abnormality associated with increased fetal morbidity and mortality. MATERIALS AND METHODS: We analyzed 62 healthy pregnant (range, 18-36 weeks) patients with focused placental sonography for detection of morphologic abnormality using the published criteria for circumvallate placenta (irregular edge, uplifted margin, or placental sheet or shelf). Placental marginal sonograms were taken at 30 degrees intervals around the entire placental margin. Five experienced sonologists who were unaware of the pathologic findings independently reviewed the placental images and graded the placentas from 1 (definitely normal) to 5 (definitely circumvallate). Receiver operating characteristic (ROC) curves and area under the ROC curve were calculated for each reader. Gross and microscopic pathology was used as the gold standard for all cases. RESULTS: In the 62 patients, sonography revealed 49 normal placentas (79%), 12 partially circumvallate placentas (19%), and one completely circumvallate placenta (2%). ROC curves for the reviewers resulted in values for area under the curve ranging from .39 to .58. The sonologist who achieved the highest value for the area under the curve classified the 13 cases of proven circumvallation as one case of definite circumvallation, four cases as uncertain or equivocal, and eight cases as probably or definitely normal placentas. Of the normal placentas, 35% were graded as probably or definitely circumvallate by at least one sonologist. All sonologists misgraded the case of complete circumvallation as normal. CONCLUSION: Focused placental sonograms interpreted by experienced sonologists fail to detect the placental edge abnormality in most cases of circumvallation. In our study, 17 of 49 normal placentas were diagnosed as probably or definitely circumvallate by one or more observers. Our sonologists' interpretations of sonograms showed that complete circumvallation was difficult to assess. Although our study had a limited number of patients, the accuracy of sonography of the placenta for revealing circumvallation appears to be limited.

Case-Control Studies↗
PubMed1994

Detection of congenital cytomegalovirus infection by using chorionic villi of the early pregnancy and polymerase chain reaction.

OBJECTIVE: To detect congenital cytomegalovirus (CMV) infection of chorionic villi in early pregnancy. METHODS: Extraction of DNA of chorionic villi and amplification of the gene of major immediate-early (MIE) antigen of CMV using a polymerase chain reaction (PCR). RESULTS: Sixty-eight specimens of chorionic villi and 16 specimens were positive for CMV infection by PCR. The incidence of congenital CMV infection in the first trimester of pregnancy was 23.5%. CONCLUSIONS: The risk of transmission of CMV from mother to fetus in early pregnancy is very high and potential CMV carriers may transmit CMV to their fetus in early pregnancy.

Chorionic Villi↗
PubMed2006

Detection of trypanosome-specific antibodies in saliva, towards non-invasive serological diagnosis of sleeping sickness.

OBJECTIVE: The detection of trypanosome-specific antibodies in saliva is technically feasible, and, if clinically validated, could become an attractive option for non-invasive diagnosis of sleeping sickness. We wanted to optimize the test format of an enzyme-linked immunosorbent assay (ELISA)-based antibody detection system. METHODS: Different ELISA formats for antibody detection in serum and saliva were developed and standardized. Saliva and serum samples were collected from 78 patient and 128 endemic control samples, and sensitivity and specificity of saliva ELISAs, serum ELISAs and the card agglutination test for trypanosomiasis (CATT), were evaluated. RESULTS: All ELISA formats showed sensitivity and specificity above 90%. Saliva ELISAs showed a similar test performance as serum ELISAs and the CATT on whole blood or serum. CONCLUSIONS: This study confirms the potential of trypanosome-specific antibody detection in saliva.

Agglutination Tests↗
PubMedDate not supplied

Prenatal detection of an interstitial deletion in 4p15 in a fetus with an increased nuchal skin fold measurement.

OBJECTIVES: The detection of an increased nuchal translucency (NT) or nuchal fold (NF) measurement is associated with an increased risk of common aneuploidies. Only rarely is it associated with other types of chromosome abnormalities. We report the prenatal finding of an increased NF in a fetus with an interstitial 4p deletion. METHODS: Standard karyotype analysis was followed by FISH with research generated BAC probes to precisely map the 4p deletion. RESULTS: The karyotype of the fetus was determined to be 46,XX,del(4)(p15.2p16.1) by G-banding analysis and was refined to 46,XX,del(4) (p15.1p15.32) after FISH analysis. The breakpoints were narrowed to 150 kb regions on each side. The deletion is approximately 14.5 Mb, containing approximately 47 genes. CONCLUSIONS: We report a case of an increased NF measurement associated with a 4p deletion. A literature review revealed a previous case of a 4p deletion in a fetus with an increased NT. Since chromosome deletions are rarely associated with an increased NT or NF, we believe it is significant that a 4p deletion has now been found in two unrelated cases. We mapped the deletion with BAC probes, generating a list of possible candidate genes involved in the pathogenesis of increased nuchal skin folds.

Chromosomes, Human, Pair 4↗
PubMed2002

Direct detection of oxygen free radicals produced in the viscera of burned rats using electron paramagnetic resonance spectroscopy.

OBJECTIVE: To detect superoxide anion (O(-)(2)) signals in the heart, liver, lung and kidney tissues after burns. METHODS: Twenty-four male rats were randomized into 4 groups. The rats of experimental groups were immersed in 100 degrees C water for 15 seconds and 25% third-degree burn was created. Thoracotomy or laparotomy was performed at 5, 10, 15, 20 and 30 minutes after burn, and specimens of the heart, lung, liver kidney were obtained for burned rats. The specimens were then preserved in liquid nitrogen for cryo-preservation and detected immediately using EPR. RESULTS: The signals of superoxide O radical appeared in the heart, lung, 1iver and kidney specimens 10-15 minutes after burn. CONCLUSIONS: There is a direct evidence of oxygen free radicals (OFRs) injury to viscera of burned rats between 10-15 minutes after burn.

Animals↗
PubMed2003

[Detection of gene promoter methylation and mRNA, protein expression levels of E-cadherin in nasopharyngeal carcinoma].

OBJECTIVE: To detect the gene promoter methylation, mRNA and protein expression levels of E-cadherin and beta-catenin in primary and metastatic tumor samples of nasopharyngeal carcinoma (NPC), and to investigate the mechanism of invasion and metastasis of neoplastic cell in NPC. METHODS: Twenty-one patients with NPC were studied. The samples of primary tumor and paired lymph node metastatic tumor were collected and examined for aberrant gene promoter methylation in E-cadherin by DNA Methylation-specific polymerase chain reaction (MSP). Reverse transcriptase polymerase chain reaction (RT-PCR), Western blotting and immunohistochemical staining were adopted to detect mRNA and protein levels of E-cadherin and beta-catenin. RESULTS: (1) The gene promoter methylation in E-cadherin was 52.4% (11/21) in primary tumor of NPC, and 80.9% (17/21) in lymph node metastatic tumor, which existed significant difference (P < 0.05). (2) In primary tumor, about 80% (0 approximately 100%) neoplastic cells expressed E-cadherin protein on the average, which was significantly higher than that of metastatic tumor (50% on the average, P = 0.004). The expression levels of beta-catenin protein were high in both primary and metastatic tumors, but with no statistic difference (P = 0.698). (3) By Western blotting analysis, the relative intensity of protein expression in E-cadherin was significantly higher in primary tumor (206.7 +/- 32.7) compared to that of metastatic tumor (65.0 +/- 15.9), while the expression of beta-catenin protein showed no difference between them (P = 0.754). (4) mRNA expression level of E-cadherin was higher in primary tumor than that of metastatic tumor.No remarkable difference was found for the mRNA expression of beta-catenin. CONCLUSIONS: (1) Downregulation of mRNA and protein expression of E-cadherin may play a critical role in neoplastic cell invasion and metastasis in NPC. The aberrant promoter methylation of E-cadherin may ultimately alter the mobility and scattering of tumor cells in NPC. (2) Downregulation of E-cadherin alone may be enough for the tumor cell to lose intercellular adhesions which results in tumor cell invasion and metastasis. However, mutant beta-catenin could also involve in this progress. (3) The detection of gene promoter hypermethylation of E-cadherin should be evaluated in the screening and surveillance of NPC.

Adult↗
PubMed2002

Detection of circulating hepatocellular carcinoma cells in peripheral venous blood by reverse transcription-polymerase chain reaction.

OBJECTIVE: To detect circulating hepatocellular carcinoma by demonstrating hepatocellular carcinoma cells or hepatocyte-associated mRNA in the nuclear cell component of peripheral blood (PBL). METHODS: Peripheral blood (5 ml samples were obtained from 93 patients with hepatocellular carcinoma (HCC) and from 33 control subjects (9 with liver cirrhosis after hepatitis B, 14 with chronic hepatitis B, 10 with normal liver function). To identify HCC cells in peripheral blood, liver-specific human alpha-fetoprotein (AFP) mRNA was amplified from total RNA extracted from whole blood by reverse transcription-polymerase chain reaction. RESULTS: AFPmRNA was detected in 50 blood samples from the HCC patients (50/93, 53.8%). In contrast, there were no clinical control patients whose samples showed detectable AFPmRNA in PBL. The presence of AFPmRNA in blood seemed to be correlated with the stage (by TNM classification) of HCC, the serum AFP value, and the presence of intrahepatic metastasis, portal vein thrombosis, tumor diameter and/or distant metastasis. In addition, AFPmRNA was detected in the blood of 21 patients with metastasis at extrahepatic organs (100%) in contrast to 29 (40.3%) of 72 patients without metastasis. CONCLUSION: The presence of AFPmRNA in peripheral blood may be an indicator of malignant hepatocytes, which might predict hematogenous spreading metastasis of tumor cells in patients with HCC.

Adult↗
PubMed2005

[Detection of quorum-sensing pathway and construction of LuxS gene deletion mutants of group B Streptococcus].

OBJECTIVE: To detect the possible presence of AI-2 quorum-sensing pathway and construct group B Streptococcus (GBS) mutants with deletion of LuxS gene related to quorum-sensing pathway. METHOD: V. harveyi BB170 was employed as the reporter strain to detect AI-2 pathway in GBS, and identification of LuxS homologous gene in GBS type V strain 2603 was performed by software-based analysis. LuxS gene deletion mutant Delta LusX was then constructed in GBS by means of allelic exchange and verified by Southern hybridization analysis. RESULTS: A component in the secretions of GBS could induce bioluminescence activity in the reporter strain, suggesting the presence of AI-2 quorum-sensing pathway in GBS. luxS homologous gene was detected in GBS and LuxS gene deletion mutants was successfully constructed in GBS Ia 515 and V 2603 strains. CONCLUSION: This study establishes a bacterial model for studying the role of LuxS molecule in AI-2 quorum-sensing pathway in GBS and provides new insights into virulence regulation mechanism of GBS.

Bacterial Adhesion↗
PubMed1997

Detection by denaturing gradient gel electrophoresis of an Arg1689Cys mutation in a Chinese patient with mild hemophilia A.

OBJECTIVE: To detect gene defects of factor VIII (F VIII) in Chinese hemophilia A patients. METHODS: 3' end of exon 14 of F VIII gene from a mild hemophilia A patient of Chinese origin was amplified by polymerase chain reaction (PCR) and identified mutations by denaturing gradient gel electrophoresis (DGGE) combining with direct sequencing. RESULTS: An upward shift band was detected by DGGE in W381. Direct sequencing demonstrated a C to T transition resulting in substitution of Arg1689Cys within a thrombin activation site of mature F VIII protein, which created a unique a thrombin activation site of mature F VIII protein, which created a unique PstI site in amplified fragment of F VIII. CONCLUSIONS: The association of PCR and DGGE can detect a single base substitution; the Arg1689Cys mutation that inhibited activation of F VIII by thrombin is a molecular defect associated with hemophilia A in W381.

Adolescent↗
PubMed1998

[Detection of minimal residual disease in acute lymphoblastic leukemia using PCR-molecule hybridization of RNA transcripts].

OBJECTIVE: To detect acute lymphoblastic leukemia's(ALL's) minimal residual disease(MRD) rapidly and effectively. METHODS: In this assay, the gamma T-cell receptor gene rearrangements serve as marker genes. The gene rearrangements are amplified from the diagnostic specimens using a consensus V segment primer and a consensus J segment primer to which the promoter T7 RNA polymerase has been appended. The PCR product from this amplification is transcribed into a radiolabeled RNA probe. The opposite DNA strand is transcribed into test RNA from the PCR product of different staged specimens. The test RNA is hybridized with the probe, and later the digestion with RNase A, Polyacrylamide gel electrophoresis and autoradiography are in progress. RESULTS: According to the mechanism, the perfectly matched RNA duplex can prevent the digestion of RNase A, and the presence of the leukemia cells in the test specimen can be determined. Logarithmical dilution experiments with DNA of a cell line from ALL have shown that this assay's sensitivity is at the 10(-5) level. Minimal residual disease was successfully detected in a case of ALL during its complete remission stage. But if the probe and test RNA are not from the same individual, the results of this kind of cross hybridization are negative. CONCLUSION: The above results suggest that this assay can become an effective measure in the detection of ALL-MRD clinically.

Child↗
PubMed1996

Neural Network Model of the Visual System: Binding Form and Motion.

We propose a neural network model of the visual system of the brain which processes different kinds of attributes such as form and motion in parallel. The model has two separate channels: a channel processing form and a channel processing motion. Each channel has both forward and backward connections, and exhibits selective attention. The selective attention mechanism, however, does not work independently because of the interaction of the two channels, which occurs at their lower layers. Both channels always focus attention on the same object even when many objects are presented simultaneously to the input layer of the model. The model was simulated on a computer: several objects made of moving random dots were applied to the input layer. At first the model focused attention on one of the objects, and detected its form and motion. It then processed the rest of the objects in turn by switching attention. Copyright 1996 Elsevier Science Ltd.

Journal Article↗
PubMed2002

Binding in short-term visual memory.

The integration of complex information in working memory, and its effect on capacity, shape the limits of conscious cognition. The literature conflicts on whether short-term visual memory represents information as integrated objects. A change-detection paradigm using objects defined by color with location or shape was used to investigate binding in short-term visual memory. Results showed that features from the same dimension compete for capacity, whereas features from different dimensions can be stored in parallel. Binding between these features can occur, but focused attention is required to create and maintain the binding over time, and this integrated format is vulnerable to interference. In the proposed model, working memory capacity is limited both by the independent capacity of simple feature stores and by demands on attention networks that integrate this distributed information into complex but unified thought objects.

Analysis of Variance↗
PubMed1982

Detection of cardiac transplant rejection with radiolabeled lymphocytes.

To determine whether rejections of cardiac transplants could be detected specifically and non-invasively by lymphocytes labeled with indium-111 (111In), we studied 36 allogeneic and 14 isogeneic heterotopic cardiac transplants in rats. Allogeneic grafts accumulated autologous 111In-lymphocytes, detectable scintigraphically 24 hours after i.v. injection of the labeled cells. At the time of peak histologic rejection, the allogeneic grafts accumulated 92. +/- 4.8 times more activity than the native hearts (determined by well counting). The tissue-to-blood ratio in the rejecting transplants was 3.7 +/- 2.2; total uptake by the graft was 2.9 +/- 2.1% of the injected dose. Autoradiography confirmed that graft radioactivity was associated with labeled lymphocytes. In contrast, isogeneic grafts showed no signs of rejection and did not accumulate radioactivity. Because conventionally isolated and labeled lymphocytes are often contaminated with platelets, we prepared both 111In-platelets and purified 111In-lymphocytes for use in additional experiments. Allogeneic grafts accumulated platelets and purified lymphocytes independently. Thus, deposition of immunologically active cells in the rejecting graft representing specific pathophysiologic events can be detected. The results suggest that rejection of cardiac transplants can be detected noninvasively, potentially facilitating objective early clinical detection of rejection and titration of antirejection therapy.

Animals↗
PubMed2001

Increased attentional blink after focal cerebral lesions.

BACKGROUND: Once a person identifies a visual object, the ability to detect a second object is impaired for the next few hundred milliseconds. This attentional blink is reported to increase in subjects with neglect due to acute right hemisphere lesions. METHOD: To examine neural substrates of the attentional blink, the authors examined the performance of 13 subjects with chronic focal brain lesions visualized by MRI and nine control subjects without neurologic impairments on a rapid serial visual presentation task that used letters as targets. RESULTS: Attentional blink length in the lesion group was more than twice that of controls (p < 0.05). The magnitude of the attentional blink deficit was greatest when the second target appeared 200 ms after the first target, recovering close to baseline by 1,200 ms. Abnormal attentional blink occurred (even in the absence of neglect) with lesions in the occipitotemporal areas (associated with "object" vision) and the prefrontal cortices (thought to mediate visual working memory). CONCLUSIONS: Attentional blink length and attentional blink magnitude measure different components of the attentional blink process. Abnormal attentional blink can occur with different chronic focal brain lesions in a network of structures for vision and attention, and it has no special status in hemispatial neglect. Abnormal attentional blink may help explain difficulties on rapid, visually demanding cognitive tasks such as reading and automobile driving and may explain performance deficits in brain damaged patients with nonspatial disorders of visual processing.

Adult↗