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Biomedical subjects

Y Kim

Publications and source records attributed to Y Kim.

1,026 records · Page 57Linked to original sources
PubMedDate not supplied

Halo sign on high resolution CT: findings in spectrum of pulmonary diseases with pathologic correlation.

The halo sign in a pulmonary nodule refers to the condition in which soft tissue attenuation of a pulmonary nodule is surrounded by peripheral ground glass attenuation on high resolution CT. The halo sign can be caused by several pathologic processes: hemorrhagic pulmonary nodules, tumor cell infiltration, and nonhemorrhagic inflammatory lesions. Hemorrhagic pulmonary nodules may occur in infectious diseases including invasive pulmonary aspergillosis, mucormycosis, and candidiasis and noninfectious diseases including Wegener granulomatosis and primary and metastatic hemorrhagic tumors. Tumor cell infiltration in bronchioloalveolar carcinoma, pulmonary lymphoma, and pulmonary metastatic neoplasm may appear with the halo sign. Eosinophilic lung disease and organizing pneumonia are representative of inflammatory lesions showing the sign.

Hemorrhage↗
PubMedDate not supplied

Bronchioloalveolar carcinoma: clinical, histopathologic, and radiologic findings.

Bronchioloalveolar carcinoma is characterized pathologically by a pulmonary neoplasm showing lepidic growth. More than half of all patients with bronchioloalveolar carcinoma are asymptomatic. The most frequent symptoms and signs are cough, sputum, shortness of breath, weight loss, hemoptysis, and fever. Bronchorrhea is unusual and a late manifestation. Nonmucinous bronchioloalveolar carcinoma tends to be more localized and has a lower frequency of bronchogenic spread than mucinous bronchioloalveolar carcinoma. Bronchioloalveolar carcinoma appears radiographically as a single nodule, segmental or lobar consolidation, or diffuse nodules. At computed tomography (CT), the single nodular form appears as a peripheral nodule or localized ground-glass attenuation with or without consolidation, frequently associated with bubblelike areas of low attenuation and open bronchus signs. The lobar consolidative form may demonstrate the CT angiogram and open bronchus signs. The diffuse nodular form appears as multiple nodules or areas of ground-glass attenuation or consolidation. The single nodular form has a better prognosis than the others but may show false-negative results for malignancy at 2-(fluorine-18) fluoro-2-deoxy-D-glucose positron emission tomography.

Adenocarcinoma, Bronchiolo-Alveolar↗
PubMedDate not supplied

Effects of mianserin on human sleep.

Sleep EEG and nocturnal penile tumescence (NPT) were investigated in 6 healthy men during placebo and mianserin administration and after mianserin withdrawal. The results were assessed in a historical comparison with those previously obtained with clomipramine. With mianserin, REM sleep was suppressed slightly. However, the suppressive effect of mianserin on REM sleep--based on the historical comparison--was significantly weaker than that of clomipramine throughout all the drug nights. Accordingly, a rebound increase in REM sleep was not observed after withdrawal. Less suppressive effects on NPT and disturbance of sexual function with mianserin than with clomipramine were observed. We suggest that a correlation between the prolonging effect on REM latency and the clinical antidepressant effect is limited to some antidepressants.

Adolescent↗
PubMedDate not supplied

Attitude change towards mental illness during nursing education--a cross-cultural study of student nurses in Korea, Republic of China and Japan.

This is an initial report of a cooperative project by colleagues in Korea, the Republic of China (Taiwan) and Japan, involving the measuring of attitudes toward mental illness. The discussion mainly revolves around the influence of mental health education in nursing on attitudes towards mental illness. The subjects' attitudes were assessed by Wig's profiles. The attitudes of freshmen who had just entered nursing schools and seniors who had already finished clinical training in psychiatry were compared to measure the attitude change during the course of nursing education, if any. Non-medical students served as a control group. As a result, a seemingly "negative and pessimistic" attitude was demonstrated in the senior student nurses. The findings are examined and discussed.

Adolescent↗
PubMedDate not supplied

Machine vision guided sensor positioning system for leaf temperature assessment.

A sensor positioning system was developed for monitoring plants' well-being using a non-contact sensor. Image processing algorithms were developed to identify a target region on a plant leaf. A novel algorithm to recover view depth was developed by using a camera equipped with a computer-controlled zoom lens. The methodology has improved depth recovery resolution over a conventional monocular imaging technique. An algorithm was also developed to find a maximum enclosed circle on a leaf surface so the conical field-of-view of an infrared temperature sensor could be filled by the target without peripheral noise. The center of the enclosed circle and the estimated depth were used to define the sensor 3-D location for accurate plant temperature measurement.

Algorithms↗
PubMedDate not supplied

Proventriculitis in broiler chickens: effects of immunosuppression.

Proventriculitis in broilers causes carcass condemnation when swollen proventriculi tear during evisceration. The cause of this proventriculitis is unknown, but several infectious agents have been associated with it. One such agent, infectious bursal disease virus (IBDV), has been implicated as a cause of proventriculitis, but a direct effect of this virus on the proventriculus has not been proven. The role of IBDV in proventriculitis may be indirect as a result of its ability to cause immunosuppression. The objective of this study was to understand how immunosuppression affects the incidence of proventriculitis in broiler chickens. Immunosuppression was induced in commercial and specific-pathogen-free broiler chickens using chemicals (cyclophosphamide and cyclosporin) or virus (IBDV). All groups were then exposed to a proventricular homogenate produced from diseased birds. At 7 and 14 days postinoculation, the incidence of proventriculitis in these groups was compared to that produced by homogenate exposure in immunocompetent broilers. All birds exposed to the proventricular homogenate from diseased birds developed proventriculitis. Cyclophosphamide and IBDV, both B cell suppressors, did not significantly affect the incidence or characteristics of the proventriculitis observed, although they did have an effect on the size of the proventriculus at 7 days postinoculation. Chickens immunosuppressed with cyclosporin, a T cell suppressor, developed more severe lesions and had a higher incidence of proventriculitis. These findings indicate that both B and T cells are involved in the immune response against proventriculitis, but cell-mediated immunity appears to have a more important role in controlling the disease. IBDV affects both humoral and cellular immunity in the chicken, so although under experimental conditions it didn't have a major effect on proventriculitis, it may explain why control of IBDV in the field seems to reduce the incidence of proventriculitis.

Animals↗
PubMedDate not supplied

Frequency specificity of amplitude-modulation-following response detected by phase spectral analysis.

To investigate the frequency specificity of steady-state responses elicited with a sinusoidally amplitude-modulated tone (amplitude-modulation-following response, AMFR), AMFR at different carrier frequencies were examined in 15 subjects with normal hearing, 12 patients with abrupt high-frequency hearing loss, 5 patients with low-frequency hearing loss and 1 patient with mid-frequency hearing loss. The stimulus was a sinusoidally amplitude-modulated tone with a modulation frequency of 40 Hz and modulation depth of 95%. Carrier frequencies were from 250 to 4000 Hz in normal subjects and from 250 to 8,000 Hz in hearing-impaired subjects. Fridman's phase spectral analysis was conducted for automatic detection of response. The thresholds of AMFR were distributed within 30 dB nHL at all carrier frequencies in normal subjects. In the hearing-impaired subjects, AMFR thresholds were between 0 and 25 dB above the behavioral threshold at all carrier frequencies. The threshold patterns of AMFR detected by phase spectral analysis very closely resembled the corresponding audiogram patterns in all types of hearing impairment. AMFR is thus shown to have a very good frequency specificity.

Acoustic Stimulation↗
PubMedDate not supplied

Distribution of lysozyme and mucin (MUC2 and MUC3) mRNA in human bronchus.

Immunocytochemical studies have shown that gel-forming glycoproteins (mucins) and the bacteriolytic protein lysozyme are selectively expressed in airway mucous and serous cells, respectively. The mechanisms mediating this selectivity are unknown. In this study, we localized mucin and lysozyme mRNA by in situ hybridization to investigate the possibility that phenotype-specific expression of these proteins is controlled at the level of mRNA. Radiolabelled sense and antisense probes were constructed from the human tracheal mucin cDNA, HAM1 (MUC2 gene), the human small intestinal mucin cDNA, SIB139 (MUC3 gene), and the bovine tracheal lysozyme cDNA, Lys 7a. Frozen sections of human bronchus were hybridized with these probes and washed under routine conditions. Autoradiography showed that although lysozyme mRNA was strictly limited to cells expressing lysozyme, mucin mRNA was present both in mucin-expressing and mucin-non-expressing epithelial cells. This suggests that the restriction of lysozyme to serous cells is controlled at the level of mRNA (synthesis and/or degradation), whereas the restriction of mucin to mucous cells is controlled at the level of translation.

Blotting, Northern↗
PubMedDate not supplied

Esophageal leiomyoma: radiologic findings in 12 patients.

OBJECTIVE: The aim of our study was to describe and compare the radiologic findings of esophageal leiomyomas. MATERIALS AND METHODS: The chest radiographic (n = 12), esophagographic (n = 12), CT (n = 12), and MR (n = 1) findings of surgically proven esophageal leiomyomas in 12 consecutive patients [ten men and two women aged 34 - 47 (mean, 39) years] were retrospectively reviewed. RESULTS: The tumors, surgical specimens of which ranged from 9 to 90 mm in diameter, were located in the upper (n = 1), middle (n = 5), or lower esophagus (n = 6). In ten of the 12 patients, chest radiography revealed the tumors as mediastinal masses. Esophagography showed them as eccentric, smoothly elevated filling defects in 11 patients and a multilobulated encircling filling defect in one. In 11 of the 12 patients, enhanced CT scans revealed a smooth (n = 9) or lobulated (n = 2) tumor margin, and attenuation was homogeneously low (n = 7) or iso (n = 4). In one patient, the tumor signal seen on T2-weighted MR images was slightly high. CONCLUSION: Esophageal leiomyomas, located mainly in the middle or distal esophagus, are consistently shown by esophagography to be mainly eccentrically elevated filling defects and at CT, lesions showing homogeneous low or isoattenuation are demonstrated.

Adult↗
PubMedDate not supplied

Radioimmunotherapy of orthotopically transplanted pancreatic cancer with 131I-labeled chimeric monoclonal antibody Nd2.

Recombinant mouse/human chimeric antibody Nd2 was previously reported to have the same specificity and reactivity against pancreatic cancer as murine Nd2 without HAMA production which induced serious problems in clinical application. We established orthotopic SW1990 transplanted mice to represent the progression of pancreatic cancer. We examined anti-tumor effect of 131I-labeled chimeric Nd2 in an orthotopic transplant model. 131I-labeled chimeric Nd2 inhibited the growth of orthotopically transplanted tumors and extended the survival time of the mice. These results suggest that 131I-labeled chimeric Nd2 has high clinical applicability in the therapy of pancreatic cancer.

Animals↗
PubMedDate not supplied

Idiopathic parkinsonism with superimposed manganese exposure: utility of positron emission tomography.

It is difficult to distinguish manganism from idiopathic parkinsonism by clinical signs only. Case history and examination: A 48-year-old welder for over 10 years complained of masked face, right side (arm and leg) resting tremor, and bradykinesia for over one year. Magnetic resonance imaging (MRI) findings showed symmetrical high signal intensities in the globus pallidus on T1 weighted image. These intensities disappeared almost completely six months after cessation of exposure. 18F-6-fluorodopa (18F-dopa) positron emission tomography (PET) findings showed reduced 18F-dopa uptake in the left putamen, findings which appear in idiopathic parkinsonism. A PET study is necessary to distinguish manganism from idiopathic parkinsonism, especially in a working environment with elevated Mn concentrations, such as welding.

Diagnosis, Differential↗
PubMedDate not supplied

Inflammatory myofibroblastic tumor of the orbit with associated enhancement of the meninges and multiple cranial nerves.

Inflammatory myofibroblastic tumor (IMT), Tolosa-Hunt syndrome (THS), and idiopathic hypertrophic pachymeningitis (IHP) seem to be part of a spectrum of disorders that have diverse locations but similar histologic and imaging findings. We report a case of a 50-year-old man presenting with multiple progressive cranial nerves palsies with leptomeningeal cranial nerve enhancement on MRI (II, V1-V3, and X), orbital and infraorbital masses, prominence within the left cavernous sinus, and diffuse dural enhancement. Biopsies of the orbital lesion and infraorbital nerve revealed IMT. The patient's lesions, symptoms, and dural enhancement quickly improved with steroid administration and nearly resolved over multiple subsequent scans over the next few months. This case illustrates a rare case of pseudotumor mimicking a more aggressive appearance that would usually portend a case of malignancy. There is a potential association of IMT, THS, and IHP, which may have existed in a concomitant fashion in this patient. The case also describes the unique finding of enhancement of the cisternal segments of multiple cranial nerves (simulating leptomeningeal malignant involvement), which may be related to inflammatory perineural edema or ischemic neuropathy.

Central Nervous System Diseases↗
PubMedDate not supplied

Serum opsonic deficiency produced by Streptococcus pneumoniae and by capsular polysaccharide antigens.

The opsonic requirements for phagocytosis of S. pneumoniae types 6, 7, 18, and 23 were determined in normal and C2 deficient serum, and in normal serum chelated with magnesium ethyleneglycoltetraacetic acid. All four strains were effectively opsonized via the alternative complement pathway, a finding suggesting that the capsular polysaccharides of these strains activated complement via the alternative pathway. Since bacteremic pneumococcal disease is often associated with circulating capsular polysaccharide, it was considered that this cellular component may activate complement in vivo and impair host defenses by producing an opsonic defect for pneumococci. To examine this hypothesis, serum was incubated with suspensions of whole S. pneumoniae types 6, 7, 18, or 23 or with purified capsular polysaccharide from each of these types, and residual complement activity and opsonic capacity were measured. Hemolytic C 3--9 complement activity and opsonic capacity for 3H-thymidine labeled Salmonella typhimurium, a species effectively opsonized via the alternative pathway, were reduced in serum following incubation. Polysaccharide concentrations as low as 1 microgram/ml inhibited serum opsonic capacity for salmonella. Whole pneumococci and pneumococcal capsular polysaccharide also inhibited the opsonic activity of human C2 deficient serum for salmonella, further evidence for activation of complement via the alternative pathway. Pneumococcal capsular polysaccharide markedly inhibited the opsonic capacity of normal serum for the homologous pneumoccal type. Thus, amounts of pneumococcal capsular polysaccharide, similar to those found in the serum of patients with pneumococcal disease, bring about decomplementation of serum via activation of the alternative pathway and inhibit pneumococcal opsonization.

Adult↗
PubMedDate not supplied

A proposed standard for evaluating the thermal performance of pediatric dispersive electrodes.

The authors have collected and analyzed 1,418 data points of current and duration of all electrosurgical unit activations from 23 surgical procedures on infants and children. The maximum radiofrequency current used was 550 mA and the duration was 4 sec. The maximum heating factor of 3.04 A2--sec was recorded at 225 mA for 60 sec. However, most data points lay between currents of 50-200 mA and durations of 1-5 sec. Using a three-dimensional computer model for a child thigh, the authors solved numerically first for the current density distribution, and then second the temperature elevation around pediatric dispersive electrodes. Derived curves showed that the maximum temperature under the electrode is proportional to the applied power and inversely proportional to the conducting area of the electrode. Analyzing results from pediatric current-duration experiments as well as computer simulation studies should assist in the design of new and improved pediatric dispersive electrodes. Finally, the authors propose a new standard for evaluating the thermal performance of pediatric dispersive electrodes.

Child↗
PubMedDate not supplied

Circadian and circannual aspects of the complement cascade - new and old results, differing in specificity.

Single cosinor analyses of several elements in the complement cascade suggest the occurrence of circadian rhythms in this immunochemical system. Some earlier results, obtained with less specific methods and reported as properdin, on reanalysis also reveal circadian and circannual rhythms in the aspects of immunology represented. The topic of the complement cascade as a whole is briefly reviewed in the content of modern knowledge.

Adult↗
PubMedDate not supplied

The effects of a breastfeeding campaign on adolescent Korean women.

A sample of 412 Korean adolescent female students were surveyed to determine their attitudes, norms, and intentions toward breastfeeding. Before completing the survey, 207 of the students were exposed to a breastfeeding campaign. A panel presentation and a video stressed the importance and advantages of breastfeeding and presented breastfeeding as a positive experience for mothers. Students exposed to the campaign showed positive attitudes and norms toward breastfeeding and indicated their intent to breastfeed. The control group of 205 students who were not exposed to the campaign showed more positive attitudes and norms toward bottlefeeding and indicated their intent to bottlefeed rather than to breastfeed. Accordingly, a breastfeeding campaign can contribute to promoting positive attitudes and norms toward breastfeeding and to the positive intentions to choose breastfeeding.

Adolescent↗