1
|
Outcomes of standard and tailored anti-tuberculosis regimens in patients with tuberculous pleural effusion. Int J Tuberc Lung Dis 2016; 20:1516-1521. [DOI: 10.5588/ijtld.16.0220] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
|
2
|
A genetic variation in microRNA target site of KRT81 gene is associated with survival in early-stage non-small-cell lung cancer. Ann Oncol 2015; 26:1142-1148. [PMID: 25716425 DOI: 10.1093/annonc/mdv100] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Accepted: 02/12/2015] [Indexed: 08/08/2023] Open
Abstract
BACKGROUND MicroRNAs (miRNAs) have a key role in carcinogenesis through negative regulation of their target genes. Therefore, genetic variations in miRNAs or their target sites may affect miRNA-mRNA interactions, thereby result in altered expression of target genes. This study was conducted to investigate the associations between single-nucleotide polymorphisms (SNP) located in the miRNA target sites (poly-miRTSs) and survival of patients with early-stage non-small-cell lung cancer (NSCLC). METHODS Using public SNP database and miRNA target sites prediction program, 354 poly-miRTSs were selected for genotyping. Among these, 154 SNPs applicable to Sequenom's MassARRAY platform were investigated in 357 patients. A replication study was carried out on an independent patient population (n = 479). Renilla luciferase assay and reverse transcription-polymerase chain reaction were conducted to examine functional relevance of potentially functional poly-miRTSs. RESULTS Of the 154 SNPs analyzed in a discovery set, 14 SNPs were significantly associated with survival outcomes. Among these, KRT81 rs3660G>C was found to be associated with survival outcomes in the validation cohort. In the combined analysis, patients with the rs3660 GC + CC genotype had a significantly better overall survival compared with those with GG genotype [adjusted hazard ratio (aHR) for OS, 0.65; 95% confidence interval (CI) 0.50-0.85; P = 0.001]. An increased expression of the reporter gene for the C allele of rs3660 compared with the G allele was observed by luciferase assay. Consistently, the C allele was associated with higher relative expression level of KRT81 in tumor tissues. CONCLUSION The rs3660G>C affects KRT81 expression and thus influences survival in early-stage NSCLC. The analysis of the rs3660G>C polymorphism may be useful to identify patients at high risk of a poor disease outcome.
Collapse
MESH Headings
- 3' Untranslated Regions
- Aged
- Binding Sites
- Carcinoma, Non-Small-Cell Lung/genetics
- Carcinoma, Non-Small-Cell Lung/metabolism
- Carcinoma, Non-Small-Cell Lung/mortality
- Carcinoma, Non-Small-Cell Lung/pathology
- Carcinoma, Non-Small-Cell Lung/therapy
- Computational Biology
- Databases, Genetic
- Female
- Gene Expression Profiling
- Gene Expression Regulation, Neoplastic
- Gene Frequency
- Genetic Predisposition to Disease
- HEK293 Cells
- Humans
- Kaplan-Meier Estimate
- Keratins, Hair-Specific/genetics
- Keratins, Hair-Specific/metabolism
- Keratins, Type II/genetics
- Keratins, Type II/metabolism
- Lung Neoplasms/genetics
- Lung Neoplasms/metabolism
- Lung Neoplasms/mortality
- Lung Neoplasms/pathology
- Lung Neoplasms/therapy
- Male
- MicroRNAs/genetics
- MicroRNAs/metabolism
- Middle Aged
- Neoplasm Staging
- Phenotype
- Polymorphism, Single Nucleotide
- Proportional Hazards Models
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Risk Factors
- Time Factors
- Transfection
Collapse
|
3
|
Trilite adsorption characteristics for perchlorate from Korean military facilities. J WATER CHEM TECHNO+ 2015. [DOI: 10.3103/s1063455x1501004x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
4
|
Radiologic and laboratory differences in patients with tuberculous and parapneumonic pleural effusions showing non-lymphocytic predominance and high adenosine deaminase levels. Infection 2014; 43:65-71. [PMID: 25385057 DOI: 10.1007/s15010-014-0697-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2014] [Accepted: 10/23/2014] [Indexed: 10/24/2022]
Abstract
PURPOSE Tuberculous pleural effusion (TPE) is characterized by lymphocytic predominance and high adenosine deaminase (ADA) levels. However, TPEs sometimes present non-lymphocytic predominance, and parapneumonic effusion (PPE) often exceeds the cutoff value of ADA for TPE. Thus, the differential diagnosis of cases with pleural fluid (PF) showing non-lymphocytic predominance and high ADA levels is challenging. However, limited data concerning the clinical differences in these patients are available. METHODS A retrospective study was conducted on TPE and PPE patients with PF showing non-lymphocytic predominance and ADA levels ≥40 U/L in 2009-2013 in a South Korean tertiary referral hospital. The clinical, laboratory, and computed tomography (CT) findings between the groups were analyzed using multivariate logistic regression to develop a prediction model with independent factors for TPE. RESULTS Among 353 patients with TPE, 24 (6.8 %) showed PF with non-lymphocytic predominance and ADA levels of ≥40 U/L. Twenty-eight PPE patients who presented PF findings comparable with those of TPE patients were included in the control group. In the final analysis, PF ADA levels >58 U/L and nodular lung lesions on CT were independent positive predictors, while loculated effusion was an independent negative predictor for TPE. Using the prediction model, a score ≥ +3 provided a sensitivity of 88 %, specificity of 93 %, positive predictive value of 91 %, and negative predictive value of 90 % for TPE. CONCLUSION PF ADA levels, nodular lung lesions, and loculated pleural effusion may help differentiate TPE from PPE in patients with PF showing non-lymphocytic predominance and ADA levels ≥40 U/L.
Collapse
|
5
|
Comparison of the incidence between tuberculosis and nontuberculous mycobacterial disease after gastrectomy. Infection 2014; 42:697-704. [PMID: 24817438 DOI: 10.1007/s15010-014-0627-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2013] [Accepted: 04/25/2014] [Indexed: 11/25/2022]
Abstract
PURPOSE Gastrectomy is a well-known risk factor for tuberculosis (TB). However, little data are available regarding the relationship between gastrectomy and the risk of nontuberculous mycobacterial (NTM) disease. Here, we investigated the incidence of TB and NTM lung disease in gastrectomized patients. METHOD New cases of TB and NTM lung infection or disease were examined among patients who had undergone gastrectomy due to gastric cancer from 2003 to 2009 at a tertiary referral hospital in South Korea. Annualized incidence rates for cases were compared with those of the general population. RESULTS This study included a total of 2,684 patients. New mycobacterial cases were found in 41 patients. Cases of TB and NTM lung infection were 35 (85 %) and 6 (15 %) including 2 NTM lung disease cases, respectively. Annualized crude incidence rates for TB, NTM lung infection, and NTM lung disease were 327/100,000, 56/100,000, and 19/100,000, respectively. The age-standardized incidence rate of TB was significantly higher in gastrectomized patients than in the general population. However, the standardized incidences of NTM lung infection and disease were not significantly different from those of non-gastrectomized patients. Patients with NTM lung infection frequently exhibited comorbid chronic lung disease, while those with TB were more frequently found to have fibronodular lesions on preoperative chest radiography. CONCLUSIONS Gastrectomy does not appear to increase the risk of NTM lung disease. However, NTM lung infection or disease should be considered as a differential diagnosis of pulmonary TB in gastrectomized patients accompanying chronic lung disease.
Collapse
|
6
|
Endoscopic bilateral stenting of malignant hilar bile duct obstruction using novel partially covered self-expandable metal stents. Endoscopy 2014; 45 Suppl 2:E328-9. [PMID: 24150731 DOI: 10.1055/s-0032-1326122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
|
7
|
Diagnostic Performance of the QuantiFERON-TB Gold In-Tube Assay and Factors Associated With Nonpositive Results in Patients With Miliary Tuberculosis. Clin Infect Dis 2014; 58:986-9. [DOI: 10.1093/cid/ciu045] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
|
8
|
Abstract
Sibutramine is an antiobesity drug that inhibits the reuptake of serotonin and noradrenalin in the hypothalamus. A 37-year-old Korean man presented to the emergency room for the oral intake of 280 mg of sibutramine. The patient was in thyrotoxic state. The 99mTechnetium-pertechnetate thyroid scan showed irregular uptake of radioisotope and thyroid-stimulating hormone receptor antibody and thyroperoxidase antibody were negative. Thyroid function normalized after that. The patient had transient thyrotoxicosis with thyroiditis. We report a case of thyrotoxicosis accompanied by thyroiditis resulting from the intentional overdose of sibutramine.
Collapse
|
9
|
Nonnegative Matrix Factorization Toward the Analysis of Frequency-Specific Resting-State Network from functional MRI Data. Neuroimage 2009. [DOI: 10.1016/s1053-8119(09)70590-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
|
10
|
Physicochemical properties, and antioxidant and antimicrobial effects of garlic and onion powder in fresh pork belly and loin during refrigerated storage. J Food Sci 2009; 73:C577-84. [PMID: 19019099 DOI: 10.1111/j.1750-3841.2008.00896.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Pork loin and belly cuts were pumped to 110% of their original weight with solutions containing 5% of various ingredients (sodium ascorbate, garlic, and onion powder), and evaluated the physicochemical properties, and antioxidant and antimicrobial activities during refrigerated storage at 8 degrees C. The addition of garlic and onion powder tended to increase redness (a) and yellowness (b) in both the belly lean and loin with the exception of a few cases. Free fatty acid values in both pork belly and loin cuts were reduced with the addition of these ingredients, as compared to the control. Significant differences in peroxide values were observed in sodium ascorbate and garlic-injected belly, and in sodium ascorbate and onion-injected loin, as compared to the control. Thiobarbituric acid reactive substance values in the pork belly with garlic or onion powder were significantly lower than in the belly without these ingredients or with sodium ascorbate (P < 0.05). Total plate counts were lower in both the belly and loin containing garlic and onion powder, as compared to the control. In both the belly and loin cuts, the content of oxidative products (volatile compounds) was reduced with the addition of garlic and onion powder, particularly the aldehydes (hexanal). Overall, garlic and onion in enhanced meats showed an antioxidant activity as effective as that of sodium ascorbate and also an antimicrobial effect to inhibit the growth of total bacteria and Enterobacteriaceae.
Collapse
|
11
|
Evaluation of lipid oxidation and oxidative products as affected by pork meat cut, packaging method, and storage time during frozen storage (-10 degrees C). J Food Sci 2007; 72:C114-9. [PMID: 17995825 DOI: 10.1111/j.1750-3841.2006.00265.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Lipid oxidation and oxidative volatiles as affected by pork meat cut and packaging method during frozen storage at -10 degrees C were evaluated. Pork belly cut had higher thiobarbituric acid reactive substance (TBARS) and pH values than did the loin, whereas the loin had higher free fatty acid (FFA) values than that of the belly cut. Peroxide values increased with increased storage time, but were not affected by pork meat cut and packaging method. Volatiles with carbon numbers less than 10 in the belly cut were higher than those in the loin cut, whereas those with carbon numbers greater than 10 in the loin cut were higher than those in belly cut. Most volatiles were decreased with increased storage time, except for propane. Both 4-pentenal and 4-methyl-2-hexanone in the belly cut showed a positive correlation with FFA, whereas 2,4-dimethyl-1-heptene and 9-octadecenal in the loin cut were positively correlated with TBARS and FFA, respectively, even though the values were not high enough to predict the degree of lipid oxidation.
Collapse
|
12
|
Prevention of autoimmune diabetes by immunogene therapy using recombinant vaccinia virus expressing glutamic acid decarboxylase. Diabetologia 2002; 45:668-76. [PMID: 12107747 DOI: 10.1007/s00125-002-0806-9] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
AIMS/HYPOTHESES Type I (insulin-dependent) diabetes mellitus results from T-cell-mediated autoimmune destruction of pancreatic beta cells. Among the beta-cell autoantigens that have been implicated in triggering of beta-cell-specific autoimmunity, glutamic acid decarboxylase (GAD) is a strong candidate in both humans and the NOD mouse. We aimed to determine whether treatment with a recombinant vaccinia virus expressing GAD (rVV-GAD65) could prevent the development of diabetes in NOD mice. METHODS Three-eight-to-nine-week-old female NOD mice were injected with various doses of rVV-GAD65 or rVV-MJ601as a control. We then examined the incidence of diabetes, T-cell proliferative response to GAD, amounts of anti-GAD IgGs, cytokine production and generation of regulatory cell populations. RESULTS Administration of rVV-GAD65 to NOD mice prevented diabetes in an age-dependent and dose-dependent manner. Splenic T cells from rVV-GAD65-treated mice did not proliferate in response to GAD65. The amount of IgG1 was increased, whereas IgG2a amounts did not change in rVV-GAD65-treated NOD mice. The production of interleukin-4 increased, whereas the production of interferon-gamma decreased in rVV-GAD65-treated mice after stimulation with GAD. Furthermore, splenocytes from rVV-GAD65-treated NOD mice prevented the transfer of diabetes by splenocytes from acutely diabetic NOD mice in NOD. scid recipients. CONCLUSION/INTERPRETATION Immunogene therapy using a recombinant vaccinia virus expressing GAD results in the prevention of autoimmune diabetes in NOD mice by the induction of immunological tolerance through active suppression of effector T cells, and this treatment might have therapeutic value for the prevention of Type I diabetes.
Collapse
|
13
|
Abstract
In an investigation of a multiresolution and multistaged approach in functional MRI, the relationship between spatial resolution and detection of functional activation is examined. The difference between functional detection and mapping is defined, and a multiresolution approach to functional detection is analyzed by constructing simple theoretical and experimental models simulating variations of in-plane resolution. Experimentally measured blood oxygenation level-dependent (BOLD) signal changes as well as BOLD contrast-to-noise ratio (CNR) with respect to different spatial resolutions are compared with results from theoretical predictions and simulation. From both an experimental and a theoretical perspective, it is shown that BOLD CNR and, thus, the concomitant detection of the functional activation are maximized when the resolution matches the size of activation.
Collapse
|
14
|
Abstract
We describe a method of interactive three-dimensional segmentation and visualization for anatomical magnetic resonance imaging (MRI) data in a personal computer environment. The visual feedback necessary during 3-D segmentation was provided by a ray casting algorithm, which was designed to allow users to interactively decide the visualization quality depending on the task-requirement. Structures such as gray matter, white matter, and facial skin from T1-weighted high-resolution MRI data were segmented and later visualized with surface rendering. Personal computers with central processing unit (CPU) speeds of 266, 400, and 700 MHz, were used for the implementation. The 3-D visualization upon each execution of the segmentation operation was achieved in the order of 2 s with a 700 MHz CPU. Our results suggest that 3-D volume segmentation with semi real-time visual feedback could be effectively implemented in a PC environment without the need for dedicated graphics processing hardware.
Collapse
|
15
|
Abstract
We used event-related fMRI methodology to investigate human brain activity during auditory imagery. A series of susceptibility-weighted MR images covering the whole brain were acquired to obtain blood oxygenation level-dependent (BOLD) signal changes associated with the imagery event of hearing simple monotone. Group analysis across the 12 right-handed subjects revealed activations in the medial and inferior frontal gyri, precuneus, middle frontal gyri, superior temporal gyri, and anterior cingulate gyri. Bilateral primary and secondary auditory areas in the superior temporal gyri also exhibited the event-related MR signal changes. The proposed method allowed for the analysis of brain areas responsive to the event of auditory imagery while our results suggest that auditory imagery and actual audition share common neural substrates.
Collapse
|
16
|
Hemodynamic effects on atherosclerosis-prone coronary artery: wall shear stress/rate distribution and impedance phase angle in coronary and aortic circulation. Yonsei Med J 2001; 42:375-83. [PMID: 11519078 DOI: 10.3349/ymj.2001.42.4.375] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
The objective of the present study was to evaluate the hemodynamic characteristics of an atherosclerosis-prone coronary artery compared to the aorta. We describe three- dimensional spatial patterns of wall shear stress (WSS) according to the impedance phase angle in pulsatile coronary and aorta models using in vivo hemodynamic parameters and computed numerical simulations both qualitatively and quantitatively. Angiography of coronary arteries and aortas were done to obtain a standard model of vascular geometry. Simultaneously to the physiologic studies, flow-velocity and pressure profiles from in vivo data of the intravascular Doppler and pressure wire studies allowed us to include in vitro numerical simulations. Hemodynamic variables, such as flow-velocity, pressure and WSS in the coronary and aorta models were calculated taking into account the effects of vessel compliance and phase angle between pressure and flow waveforms. We found that there were spatial fluctuations of WSS and in the recirculation areas at the curved outer wall surface of the coronary artery. The mean WSS of the calculated negative phase angle increased in the coronary artery model over that in the aorta model and the phase angle effect was most prominent on the calculated amplitude of WSS of the coronary artery. This study suggests that the rheologic property of coronary circulation, such as the fluctuation of WSS/WSR induces several hemodynamic characteristics. A separation of flow-velocity, a difference in phase between pressure conductance and blood flow and prominent temporal and/or spatial oscillatory fluctuations of the shear forces as a function of pulsatile flow might be important factors in atherogenesis and progression of atherosclerosis.
Collapse
|
17
|
Abstract
OBJECTIVE Previous research has noted functional and structural temporal lobe abnormalities in schizophrenia that relate to symptoms such as auditory hallucinations and thought disorder. The goal of the study was to determine whether the functional abnormalities are present in schizophrenia at early stages of auditory processing. METHOD Functional magnetic resonance imaging activity was examined during the presentation of the mismatch stimuli, which are deviant tones embedded in a series of standard tones. The mismatch stimuli are used to elicit the mismatch negativity, an early auditory event-related potential. Ten patients with schizophrenia and 10 comparison subjects were presented the mismatch stimuli condition and a control condition in which only one tone was presented repeatedly. RESULTS The superior temporal gyrus showed the most prevalent and consistent activation. The superior temporal gyrus showed less activation in the schizophrenic subjects than in the comparison subjects only during the mismatch stimuli condition. CONCLUSIONS This result is consistent with those of mismatch negativity event-related potential studies and suggests that early auditory processing is abnormal in chronic schizophrenia.
Collapse
|
18
|
Abstract
Recent laboratory experiments have demonstrated that cyclin D1 levels (cycD1) can influence radiosensitivity. The purpose of the current study is to evaluate the prognostic significance of cycD1 for local recurrence in early-stage larynx cancer treated with primary radiation therapy. The study was conducted using a matched case-control design in 60 early-stage (T1-T2/N0) larynx cancer patients. All patients had squamous cell carcinoma of the larynx and were treated with primary radiation to a total median dose of 66 Gy in daily fractions of 2 Gy, without surgery or chemotherapy. Thirty patients who suffered a local relapse in the larynx after treatment served as the index case population. These 30 cases were matched by age, sex, site (glottic vs. supraglottic), radiation therapy technique/dose, and follow-up, to 30 control patients who did not experience a local relapse. Immunohistochemical staining from cycD1 was performed on the paraffin-embedded specimens. The pathologist, blinded to the clinical information, scored each of the specimens on a four-point intensity scale (0 = no stain, 1 = faint, 2 = moderate, 3 = strong) and percent distribution. Patients were considered to be positive for cyclin D1 if the staining was 2+ or greater with a percent distribution of at least 5%. By design of the study, the two groups were evenly balanced with respect to age, sex, stage, radiation dose, and follow-up. CycD1 levels correlated with proliferating cell nuclear antigen levels. Low levels of cycD1 significantly correlated with local relapse; 19/30 (63%) of the index cases stained negative, while only 10/30 (33%) of the control cases stained negative (P = 0.03). These data suggest that low levels of cycD1 correlate with relatively radioresistant early-stage larynx carcinoma. With larger more confirmatory clinical and laboratory data, this data may have significant clinical implications. Int. J. Cancer (Radiat. Oncol. Invest.) 90, 22-28 (2000).
Collapse
|
19
|
Transglycosylation of neohesperidin dihydrochalcone by Bacillus stearothermophilus maltogenic amylase. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2000; 48:152-154. [PMID: 10691608 DOI: 10.1021/jf991044y] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Neohesperidin dihydrochalcone (NHDC), a sweet compound derived from citrus fruits, was modified to a series of its oligosaccharides by transglycosylation activity of Bacillus stearothermophilus maltogenic amylase (BSMA). Maltotriose as a donor was reacted with NHDC as an acceptor to glycosylate for the purpose of increasing the solubility of NHDC. Maltosyl-NHDC was a major transglycosylation product among the several transfer products by TLC analysis. The structure of the major transglycosylation product was determined to be maltosyl-alpha-(1,6)-neohesperidin dihydrochalcone by MALDI-TOF/MS and (1)H and (13)C NMR. Maltosyl-NHDC was 700 times more soluble in water and 7 times less sweet than NHDC.
Collapse
|
20
|
Abstract
Adaptively limiting image acquisition to areas of interest will allow more efficient data acquisition time for in-depth characterization of areas of brain activation. We designed and implemented an adaptive image acquisition scheme that uses a multiresolution-based strategy to zoom into the regions of cortical activity. Real-time pulse prescription and data processing capabilities were combined with spatially selective radiofrequency encoding. The method was successfully demonstrated in volunteers performing simple sensorimotor paradigms for simultaneous activation of primary motor and cerebellar areas. We believe that real-time adaptation of spatial and temporal sampling to task-related changes will increase the efficiency and flexibility of functional mapping experiments. Contrast-to-noise analysis in selected regions-of-interest was performed to quantitatively assess the multiresolution adaptive approach.
Collapse
|
21
|
Abstract
We propose a new approach using wavelet encoding to improve temporal resolution in contrast-enhanced magnetic resonance (MR) imaging. Exploiting the unique property of wavelets localized in space and frequency, we construct an efficient encoding scheme to capture signal changes due to contrast agent uptake, which in general is spatially localized with low- and mid-range frequency components. On the basis of space-frequency analysis, we describe mathematical formulations of our method and discuss its theoretical advantages over Fourier-based phase-encoding methods (the keyhole and reduced-encoding imaging by generalized-series reconstruction [RIGR] techniques). The results obtained in computer simulations and a phantom study demonstrate the feasibility and practical advantages of our approach.
Collapse
|
22
|
Abstract
A new method for functional magnetic resonance imaging (fMRI) employing non-Fourier encoding using spatially selective radiofrequency (RF) excitation is presented. The method uses manipulation of spatially selective RF pulses to encode spins in the slice-select direction. The method has several advantages over standard multislice approaches. It provides a simple means for monitoring irregularly distributed sections throughout a volume without the need to encode the whole volume. It offers the potential for increased signal-to-noise ratio if an appropriate basis is used for encoding. With a unique design of excitation pulses, it also appears possible to significantly reduce in-flow effects. An interleaved echo-planar imaging (EPI) sequence was adapted for non-Fourier encoding in the slice-select direction and was implemented on a conventional 1.5-Telsa system. The method was then used for functional mapping of the visual and motor areas where significant reduction of in-flow effect was demonstrated. This approach can be adapted to other imaging sequences that are used for fMRI, such as single-shot EPI.
Collapse
|
23
|
CdZnTe array detectors for synchrotron radiation applications. JOURNAL OF SYNCHROTRON RADIATION 1998; 5:1332-6. [PMID: 16687845 DOI: 10.1107/s0909049598007237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/1997] [Accepted: 05/19/1998] [Indexed: 05/09/2023]
Abstract
An X-ray linear-array detector was fabricated using high-pressure Bridgman-grown CdZnTe. The detector area was 175 x 800 microm and the pitch size was 250 microm. The measured dark current for the test 16-element detector was as low as 0.1 pA at 800 V cm(-1) with excellent uniformity. Energy spectra were measured using a 57Co radiation source. Both a small-pixel effect and charge sharing were observed. For the arrays, an average 5.8% full width at half-maximum (FWHM) at the 122 keV photopeak was obtained with a standard deviation of 0.2%. A large-area detector (1 x 1 cm) of the same material before fabrication exhibited a low-energy tail at the photopeak, which limits the photopeak FWHM to 8%, typically due to hole trapping. At energies below 60 keV, charge sharing between elements was observed. The charge sharing was greatly reduced by providing a path to ground for unwanted charges. A prototype readout electronic system for an eight-channel array detector was developed. A readout system intended for a multielement solid-state detector system was also used. The array detector will be used for high-energy diffraction and Compton scattering measurements at the Advanced Photon Source.
Collapse
|
24
|
Abstract
A new digital wavelet-encoding method for MRI is described. The method differs from previously described wavelet-encoding approaches, because the point-spread function is made independent of the wavelet basis used. This has a significant practical advantage, because wavelet bases can now be considered that would otherwise be excluded due to the difficulty of precisely exciting wavelet-shaped RF profiles. The method has been implemented on a clinical MRI system, and human images are presented.
Collapse
|
25
|
Abstract
The objectives of this investigation are to evaluate the rheologic properties in atherosclerotic disease treated with the various coronary artery bypass graft (CABG) models by numerical analysis, we used four different CABG models for the assessment of spatial fluctuation in wall shear stress, pressure variation and mass flow rate with Carreau model and Navier-Stokes equation. Wall shear stress was higher in a naturally tapered model (model 1) and a constant (non-tapered) diameter of the graft vessel the same as the distal LAD (model 4) than in others. Pressure variation along the native coronary artery and graft vessels was higher in a model 4, model 1 than in a reverse tapering model (model 2) and a constant diameter of the graft vessel the same as the proximal LAD (model 3). The mass flow rate of the distal part (kg/sec,.m(o)) was the highest in model 3. This study suggests that in vitro spatial simulation following CABG revealed that small caliber or tapered graft vessels have adverse hemodynamic effects on the native and graft vessels. By this technique it is possible to simulate the optimal distribution of local hemodynamic variables in patients treated with CABG, also to minimize the degeneration of graft vessel.
Collapse
|
26
|
Computed numerical analysis of the biomechanical effects on coronary atherogenesis using human hemodynamic and dimensional variables. Yonsei Med J 1998; 39:166-74. [PMID: 9587258 DOI: 10.3349/ymj.1998.39.2.166] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The objectives of this investigation were to evaluate biomechanical factors in the atherosclerotic process using human in vivo hemodynamic parameters and computed numerical simulation qualitatively and quantitatively. The three-dimensional spatial patterns of steady and pulsatile flows in the left coronary artery were simulated, using a finite volume method. Coronary angiogram and Doppler ultrasound measurement of the proximal left coronary flow velocity were performed in humans. Inlet wave velocity distribution obtained from in vivo data of the intravascular Doppler study allowed for input of in vitro numerical simulation. Hemodynamic variables, such as flow velocity, pressure and shear stress of the left anterior descending coronary bifurcation site were calculated. We found that there were spatial fluctuation of flow-velocity and recirculation areas at the curved outer wall of the left anterior descending coronary artery, which were due to the differences of flow-velocity and shear stress, especially during the declaration phase of pulsatile flow. This study suggests that rheologic properties may be a part of the atherogenic process in the coronary bifurcated and curved areas.
Collapse
|
27
|
Hospital consent for disclosure of medical records. THE JOURNAL OF LAW, MEDICINE & ETHICS : A JOURNAL OF THE AMERICAN SOCIETY OF LAW, MEDICINE & ETHICS 1998; 26:241-179. [PMID: 11066882 DOI: 10.1111/j.1748-720x.1998.tb01425.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Disclosure of information clauses in general consent-to-treatment forms used by 202 large hospitals nationwide are described and mapped into a taxonomy to distinguish types of disclosures and to help structure consent documents.
Collapse
|
28
|
Abstract
To rapidly track invasive devices within MRI systems, a novel approach using a limited projection reconstruction technique is presented. Our method exploits the difference between images reconstructed from a limited number of projections and serves to depict the tip of a needle during its advancement. This method was implemented on a standard MRI system with a radial fast-spin-echo sequence and examined in phantom studies. We demonstrated that the proposed method could track the tip every 300 msec and the tip depicted by the present technique was consistently displaced along the needle by a small distance (5 mm).
Collapse
|
29
|
Glutamine supplementation maintains intramuscular glutamine concentrations and normalizes lymphocyte function in infected early weaned pigs. J Nutr 1997; 127:2253-9. [PMID: 9349855 DOI: 10.1093/jn/127.11.2253] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Numerous studies in humans and rats have shown that glutamine supplementation during stressful conditions has favorable outcomes. However, the requirements for glutamine during weaning are unknown. Thus, the effects of glutamine supplementation in healthy and infected weaned pigs were investigated. At 21 d of age, pigs were weaned to an elemental diet supplemented with glutamine (+Gln) or an isonitrogenous diet containing nonessential amino acids (-Gln). At 26 d of age, pigs were intraperitoneally injected with Escherichia coli (+Ecoli) or buffered saline (-Ecoli) and killed at 28 d of age. Infection decreased (P < 0.05) plasma and intramuscular glutamine concentrations, but infected pigs that received +Gln diets had higher intramuscular glutamine levels than those that received -Gln diets. Infected pigs had elevated (P < 0.05) total leukocyte counts, and blood lymphocyte responses ([3H]-thymidine incorporation) to a mixture of phorbol myristate acetate and ionomycin were reduced. White blood cell counts were greater (P < 0.05) in +Gln than -Gln pigs. The peak responses to concanavalin A (Con A) by lymphocytes of +Ecoli+Gln pigs were greater (P < 0.05) than those of +Ecoli-Gln pigs and not different than those of noninfected pigs. Hence, glutamine supplementation maintained muscular glutamine concentrations and normalized lymphocyte function in infected pigs.
Collapse
|
30
|
3D localization of surface 10-20 EEG electrodes on high resolution anatomical MR images. ELECTROENCEPHALOGRAPHY AND CLINICAL NEUROPHYSIOLOGY 1997; 102:335-9. [PMID: 9146495 DOI: 10.1016/s0013-4694(96)95088-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
A method to visualize surface EEG electrodes on conventional high-resolution magnetic resonance (MR) images is presented. Because conventional silver or gold electrodes generate an insignificant artifactual signal signature in MR images, a plastic capsule filled with gadolinium-doped water was designed to mold onto each electrode, thereby outlining the electrode surfaces as a negative imprint on MR images. MR images of the head with capsules affixed clearly demonstrated the location and shape of the electrodes. Selected cranial tissues were identified by using semi-automatic image segmentation to determine their three-dimensional spatial relationship to the electrodes. Such representations could be used as a starting point for more precise EEG source localization modeling applicable to individual patients.
Collapse
|
31
|
|