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J H Shin

Publications and source records attributed to J H Shin.

At least 109 records · Page 6Linked to original sources
PubMed1997

Molecular typing of Vibrio vulnificus isolates by random amplified polymorphic DNA (RAPD) analysis.

This study was undertaken to determine molecular types and genetic similarity among V. vulnificus isolates by RAPD analysis. We compared these results with serotypes of V. vulnificus. Ninety-seven V. vulnificus strains including 69 strains from Chonnam University Hospital (CUH; Kwangju, Korea), 13 from Wonkwang University Hospital (WUH; Iksan, Korea), 13 from the Japanese National Institute of Health (JNIH) and two reference strains (ATCC 33815 and ATCC 27562) were analyzed. Four molecular types comprising all the strains were obtained by RAPD analysis. Type I was the most common (60/95) and included 58 strains from CUH. Type I showed a further subdivision into seven subtypes. Type II (23/95) composed of 11 strains from CUH, nine from WUH, three from JNIH and two reference strains. Six type III strains comprised four WUH strains and two JNIH strains. All six strains of type IV were from JNIH. The range of genetic similarity values among V. vulnificus isolates was 0.24 to 1.00. The serotypes of 95 strains were 04 (84.2%), 014 (3.2%), 01 (2.1%), 013 (2.1%), and R (2.1%). The most common 04 serotype strains were distributed among types I (60 strains), II (23 strains), III and IV (six strains). Although the V. vulnificus isolates showed a wide range of genetic similarity values, RAPD analysis could separate V. vulnificus strains into four molecular types, and the isolates from the same hospitals tended to belong to the same molecular type. There was no specific correlation between molecular types and serotypes of V. vulnificus.

Random Amplified Polymorphic DNA Technique↗
PubMed1997

Secondary craniofacial management following initial correction of nonsyndromic craniosynostosis.

Marked technical improvements in the surgical management of craniosynostosis have come hand-in-hand with refinements in anesthesia, intensive care, and radiographic image analysis. At the beginning of the second century of the care of these patients, we now have a variety of sophisticated options that represent safer, more physiologically sound and aesthetically more pleasing options for the correction of secondary problems in craniosynostosis.

Cephalometry↗
PubMed1996

Fast and slow gating types of SR ryanodine receptor/channel purified from canine latissimus dorsi muscle.

The ryanodine receptor/channel (RyR) mediates the release of calcium from the sarcoplasmic reticulum (SR) in both skeletal and cardiac muscle cells. There are three isoforms of the RyR: RyR1, RyR2, and RyR3. RyR1 is specifically expressed in skeletal muscles and RyR2 in cardiac muscles. RyR3 is yet another isoform found in non-muscle cells such as neuronal cells. Single channel recordings of RyR1 and RyR2 reconstituted in artificial lipid bilayer show that the characteristics of two isoforms are very distinct. RyR1 has a shorter mean open time and is activated at a higher concentration of Ca2+ than RyR2. In this study, we isolated the heavy SR membranes from canine latissimus dorsi muscles and investigated the single channel activities from the heavy SR membrane fraction using Cs+ as a charge carrier. Two different types of activities were observed. The fast-gating type (FG) with the mean open time of 0.9 ms was more frequently recorded (n = 12) than the slow-gating type (SG) with the mean open time of 269.2 ms. From the I-V relation, the slope conductance of the FG was calculated to be 514.7 pS and the SG, to 625.6 pS. The activity of the fast gating type increased by raising the concentration of Ca2+ in the cis-solution up to 100 microM. The appearance of the SG in the canine heavy SR membrane fraction suggests a possibility that two types of RyR isoform are co-expressed in mammalian skeletal muscle as well as in avian, amphibian and piscine fast twitch muscles.

Animals↗
PubMed1996

Idiopathic granulomatous hepatitis manifested with fever of unknown origin.

Idiopathic granulomatous hepatitis is a rare disease of unknown cause that is characterized by recurrent fevers and granuloma in the liver. Attempts to define an exact etiology of the fever of granulomatous hepatitis frequently do not yield a precise diagnosis. Idiopathic granulomatous hepatitis was confirmed after a thorough work up and negative cultures and serologies were obtained, and in the absence of another condition that could lead to granulomas in the liver. We have experienced a 67-year-old female patient who presented with prolonged fever for 2 months and revealed granuloma in liver biopsy. She was treated with glucocorticosteroid and defervescence resulted.

Aged↗
PubMed1996

Alternative use of polymerase chain reaction instead of rho-nitro-alpha-acetylamino-beta-hydroxypropiophenone test for the early detection of Mycobacterium tuberculosis in BACTEC 12B cultures.

Compared with conventional culture media, the TB BACTEC system has demonstrated improved isolation rates as well as an earlier detection time for mycobacterial species. However, the identification of M. tuberculosis by the rho-nitro-alpha-acetylamino-beta-hydroxypropiophenone (NAP) test in the TB BACTEC 460 system may require 6 days for interpretable results. We evaluated the usefulness of a polymerase chain reaction (PCR) assay for earlier identification of M. tuberculosis in positive BACTEC 12B cultures. A total of 262 TB BACTEC culture specimens with GIs > or = 10 were assayed by PCR, and the results were compared with those of the NAP test. The aliquot from BACTEC 12B vials was boiled for 10 min, and 2 microliters of the boiled suspension was used for the PCR assay. One set of primers based on the IS 6110 sequence of M. tuberculosis was used to amplify a 457 bp fragment of DNA. Of the 173 TB BACTEC culture specimens which were identified as M. tuberculosis by the NAP test. 171 were PCR positive. Of the 21 TB BACTEC cultures identified as MOTT by the NAP test. 19 were PCR negative, but 2 were PCR positive: these two cultures were shown to grow both M. tuberculosis and MOTT in BACTEC 12B vials. Of the remaining 68 cultures which were contaminated with AFB-negative bacteria, the PCR identified M. tuberculosis in 13, in agreement with the NAP results in the reprocessed specimens. Overall, the PCR results in the 262 BACTEC culture specimens with GIs > or = 10 were sensitive in 99.5% (186/187) and specific in 100% (68/68). The mean time for the identification of M. tuberculosis in TB BACTEC cultures with GIs > or = 10 was 7 h by the PCR compared to 5.9 days by the NAP test. These results suggest that the PCR could be used as an alternative to the NAP test for the rapid identification of M. tuberculosis in BACTEC 12B cultures, particularly in those which contained both M. tuberculosis and MOTT or M. tuberculosis and AFB-negative bacteria.

Bacteriological Techniques↗
PubMed1995

In vitro differentiation of the murine macrophage cell line BDM-1 into osteoclast-like cells.

Osteoclasts are derived from hematopoietic stem cells, but details about their precursor are still obscure. We present here a mouse macrophage cell line, BDM-1 cells, that showed a high potential to differentiate into osteoclast-like multinucleate cells (MNCs) when cocultured with primary osteoblasts for 14 days in the presence of 10(-8) M 1 alpha,25-dihydroxyvitamin D3. These MNCs had tartrate-resistant acid phosphatase (TRAP) activity and strong ability to resorb dentine. In this culture system, 10(-10)-10(-8) M 12-O-tetradecanoylphorbol-13-acetate stimulated the formation of TRAP-positive MNCs, whereas salmon calcitonin inhibited it. Time-course effect studies showed that 12-O-tetradecanoylphorbol-13-acetate had an effect on the late phase of osteoclast differentiation but not on precursor proliferation. By immunocytochemical staining, all BDM-1 cells expressed Mac-1, Mac-2, and MOMA-2 antigens, and a large number of them expressed F4/80 antigen, but the rest of them were negative for this antigen. To select subclones able to differentiate into TRAP-positive MNCs, we sought to isolate several subclones from BDM-1 cells by mean of different specificity for F4/80 antigen expression. TRAP-positive MNCs were not generated from F4/80-positive subclones, but were obtained from subclones containing F4/80-negative cells. These results suggest that an F4/80-negative macrophage subpopulation is responsible for the differentiation of this cell line into osteoclasts.

Acid Phosphatase↗
PubMed1995

Vascular lesions of the cranial base.

Vascular lesions can be classified broadly into two groups on the basis of cellular proliferation characteristics: hemangiomas and vascular malformations. Additional lesions include a heterogeneous group of vascular tumors such as those represented by hemangiopericytoma and those with a frankly malignant course. Those lesions located around the cranial base remain challenging and difficult clinical problems. The care of patients with these problems is complex; it frequently will need a full spectrum of individuals from many disciplines involved in many diverse aspects of management: medical, radiologic, anesthetic, and surgical. Fortunately, advances in science and technology have markedly expanded our capability in treating these patients and have allowed us increasing safety and ease in dealing with previously untreatable and unresectable lesions.

Brain Neoplasms↗
PubMed1994

Correlation between blood pressure changes assessed by 24-hour ambulatory blood pressure monitoring and urine microalbuminuria excretion rate in normal and essential hypertension.

To document the correlation between renal damage and circadian blood pressure variation, urinary microalbumin excretion rate (UAER) and 24-hour ambulatory blood pressure monitoring (24-hr ABPM) were performed in 16 normotensives and 29 stage I-III essential hypertensive subjects (whole-day mean BP; 120.13/79.06 mmHg vs 152.59/94.31 mmHg, p < 0.05). The BP variables of 24-hr ABPM included hourly mean arterial pressure (MAP), maximum, minimum and mean systolic and diastolic BP of the awaking (daytime) and sleep time (nighttime), and whole-day mean BP. Subsequently, BP reduction of maximum, minimum and mean BP between awaking time and sleep time were also calculated as other variables. UAER was not different between the normotensive and hypertensive group (9.44 +/- 11.48 vs 11.87 +/- 9.27 micrograms/min, p > 0.05). 10 subjects (2/16 in normal vs 8/29 subjects in hypertensives) revealed over 16 micrograms/min of UAER. All of the awaking BP variables and whole-day mean BP were correlated with the UAER in whole subjects and hypertensives, but almost sleep BP variables except maximum DBP and mean DBP were not. On the contrary, only daytime minimum DBP and SBP were correlated with UAER in normotensives. The common best correlated BP variable in awaking time was minimum BP (DBP and SBP; r = 0.49, r = 0.44 in whole, r = 0.51, r = 0.58 in hypertensives, r = 0.54, 0.56 in normotensives, all p < 0.05). Hourly MAP at 24 PM in whole subjects (r = 0.49, p < 0.05) and that of at 22 PM in hypertensives were best correlated (r = 0.71, p < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Induction of mononuclear precursor cells with osteoclastic phenotypes in a rat bone marrow culture system depleted of stromal cells.

The importance of bone stromal cell involvement in osteoclast differentiation has been suggested. However, the detailed mechanism of its regulation is unclear. We investigated whether the soluble factors from osteoblastic cells influence osteoclast lineage cells in a population of rat bone marrow cells depleted of stromal cells. We show here that hematopoietic progenitor cells differentiate into mononuclear precursor cells, the preosteoclasts, that strongly express certain osteoclastic phenotypes in the absence of stromal cells. The multinucleation of the preosteoclasts occurred only in the presence of 1,25 dihydroxyvitamin D3 and stromal cells. The preosteoclasts themselves did not have dentine-resorbing activity, but they could differentiate into multinucleate osteoclast-like cells having such activity in the presence of rat primary osteoblasts. This culture system is a unique differentiation system for preosteoclast induction.

Animals↗
PubMed1993

Effect of problem-based, self-directed undergraduate education on life-long learning.

OBJECTIVE: To compare how well graduates of a self-directed, problem-based undergraduate curriculum (at McMaster University [MU], Hamilton, Ont.) and those of a traditional curriculum (at the University of Toronto [UT]) who go on to primary care careers keep up to date with current clinical practice guidelines. DESIGN: Analytic survey. Management of hypertension was chosen as an appropriate topic to assess guideline adherence. An updated version of a previously validated questionnaire was mailed to the participants for self-completion. SETTING: Private primary care practices in southern Ontario. PARTICIPANTS: A random sample of 48 MU graduates and 48 UT graduates, stratified for year of graduation (1974 to 1985) and sex, who were in family or general practice in Ontario; 87% of the eligible subjects in each group responded. MAIN OUTCOME MEASURES: Overall and component-specific scores; analysis was blind to study group. RESULTS: The overall mean scores were 56 (68%) of a possible 82 for the MU graduates and 51 (62%) for the UT graduates (difference between the means 5, 95% confidence interval 1.9 to 8.2; p < 0.01). Multivariate linear regression analysis of seven factors that might affect questionnaire scores revealed that only the medical school was statistically significant (p < 0.01). The MU graduates had significantly higher mean scores than the UT graduates for two components of the questionnaire: knowledge of recommended blood pressures for treatment (p < 0.05) and successful approaches to enhance compliance (p < 0.005). The trends were similar for the other components but but were not significant. CONCLUSIONS: The graduates of a problem-based, self-directed undergraduate curriculum are more up to date in knowledge of the management of hypertension than graduates of a traditional curriculum.

Curriculum↗
PubMed1993

Harvey Cushing: first guest at "The Divine Banquet of the Brayne".

Harvey Cushing will remain forever ensconced in surgical memory as the visionary who established contemporary neurosurgery. Raised in Cleveland in a middle-class family with a medical background, he gave little indication early of his later prowess. A college education at Yale University yielded a modest performance, although he showed somewhat better promise as a medical student at Harvard University. During his surgical training at the Johns Hopkins Medical School, he emerged as a bright, industrious young man with a glint of steel to his intellect. From Halsted he learned the academic basis of surgery and the meticulousness necessary for technical success. Osler became his friend and provided him with a foundation in the history of medicine and the recognition of its importance in shaping the future. The decision to spend a year in Europe visiting clinics and renowned surgeons may have laid the foundations for the subsequent configuration of his career. In Britain he saw firsthand the glorious museums and libraries of the Hunters and the legacy that their schools of surgery had endowed to the nation. In Paris and London he mixed with the surgical aristocracy of the times and learned the power of societies and the traditions of their patrons. In Berne he was exposed to the surgical purity and physiologic expertise of Kocher, supported by the estimable scientific practice of Kroneker. As an "arbeid," Kocher posed him the problem of establishing the mechanism of the regulation of cerebral perfusion. This question, which he so rapidly and successfully unraveled, probably played a large part in igniting his enthusiasm toward the study of the brain as a future career. In his travels he encountered diverse intellects and experienced a wide panoply of European medical thought. He conversed widely at both a social and professional level and integrated all information into meticulously kept diaries that served as not only a record but also a template from which later plans were derived. A final 6-week sojourn in Liverpool working on the primate cortex with Sherrington, the greatest neurophysiologist of that time, may have sealed his decision to turn his initial project with Kocher into the opus of a lifetime. The 14-month tour of Europe transformed Cushing from a relative unsophisticate into a figure of giant proportions. All that he experienced became part of his life and was integrated into his subsequent career.(ABSTRACT TRUNCATED AT 400 WORDS)

Europe↗
PubMed1989

Subtle gastric abnormalities in a canine model: detection with low-dose imaging with storage phosphors and its equivalence to conventional radiography.

The authors compared low-dose (32% of standard exposure) storage phosphor digital imaging (system resolution: 0.2-mm pixels, 10 bits) with isovoltage 75-kVp conventional radiography (standard exposure) in the detection of subtle simulated gastric abnormalities by using air contrast barium studies. Subtle simulated abnormalities (3-7-mm polyps, 4-15-mm ulcer craters, 4-11-mm-diameter edema, and 11-12-mm linear ulcers) were produced in resected canine stomachs. Receiver operating characteristic analysis of 1,800 observations by six readers indicated that the digital images with and without high-frequency edge enhancement were equivalent to conventional radiographs (mean receiver operating characteristic areas [+/- standard deviation]: 0.76 +/- 0.06, 0.78 +/- 0.04, and 0.77 +/- 0.04, respectively). The accuracy of the diagnosis was equivalent for all three modalities. The following mean accuracies of negative and positive responses, respectively, for unenhanced digital, edge-enhanced digital, and conventional images were determined: 0.71 +/- 0.05 and 0.41 +/- 0.07, 0.71 +/- 0.04 and 0.51 +/- 0.09, and 0.68 +/- 0.04 and 0.43 +/- 0.05. It was concluded that low-dose storage phosphor air-contrast barium studies were equivalent to conventional radiography in the detection of subtle gastric abnormalities.

Animals↗
PubMed1981

Purification of the lysosomal acid lipase from human liver and its role in lysosomal lipid hydrolysis.

The lysosomal acid lipase has been purified 2,500-fold to near homogeneity from human liver. The enzyme was converted to a soluble form by extraction of frozen tissue with Triton X-100. The enzyme, which required Triton X-100 in buffers at all purification steps for optimal yields, was stabilized by the inclusion of 33% ethylene glycol during purification. Lectin chromatography on concanavalin A-Sepharose followed by chromatography on carboxymethyl-cellulose and Sephadex G-150 provided the highly purified enzyme in 17% yield. Sodium dodecyl sulfate-acrylamide gel electrophoresis indicated that the minimum molecular weight was about 29,000 +/- 1,000. Minor protein contaminants at Mr = 58,500, 14,700 and 13,900 were present in the final preparation. A single protein band, with enzyme activity, was observed in nondenaturing acrylamide gels containing Triton X-100. Gel filtration on Sephadex G-150 in the presence of Triton X-100 gave an apparent molecular weight of about 125,000 +/- 13,000. Trioleoylglycerol, cholesterol oleate, and 1,2- and 1,3-dioleoylglycerols were substrates for the purified enzyme giving apparent Vmax values of 5,400, 1,400, 19,400, and 22,100 nmol min-1 mg of protein-1, respectively, and Km values of 0.8, 0.8, 0.9, and 1.2 mM, respectively. The recoveries of both trioleoylglycerol and cholesterol oleate hydrolytic activities were nearly identical at each purification step, suggesting that the acid lipase as single enzyme is responsible for lysosomal hydrolysis of the neutral lipids. Monooleoylglycerols were not substrates for the enzyme.

Drug Stability↗
PubMed1980

Separation and characterization of the acid lipase and neutral esterases from human liver.

Electrophoresis of human liver homogenates followed by reaction with 4-methylumbelliferyl palmitate reveals the presence of two major electrophoretic forms with esterase (lipase) activity toward this substrate. The two enzymes were isolated and partially purified based on their solubility differences and their relative affinities for the lectin column concanavalin A-Sepharose 4B. Lipase A was particulate with an acidic pH optimum (5.2) and could be solubilized with the non-ionic surfactant Triton X-100. Lipase B was soluble and had a more neutral pH optimum (6.3--6.6). Both forms bound to immobilized concanavalin A and could be specifically eluted. Buffers containing alpha-methylmannoside eluted lipase B, and buffers with alpha-methylmannoside and Triton X-100 eluted lipase A, giving a 22- and 257-fold purification, respectively, over whole-tissue homogenates. Cholesterol oleate, trioleoylglycerol, and 4-methylumbelliferyl palmitate were substrates for solubilized lipase A. Lipase B hydrolyzed 4-methylum-belliferyl palmitate but not trioleoylglycerol or cholesterol oleate. Lipase B was more thermolabile than lipase A, and it was selectively inhibited by diethyl-p-nitrophenyl phosphate at low concentrations. We conclude that lipase A and B are distinctly different enzymes and that they are probably not related polymorphic forms of one another.

Chromatography, Affinity↗
PubMedDate not supplied

Choroid plexus papilloma in the posterior cranial fossa: MR, CT, and angiographic findings.

In this study, we reviewed the magnetic resonance (MR, n=5), computed tomography (CT, n=3), and angiography (n=3) of six patients with pathologically confirmed choroid plexus papilloma (CPP) in the posterior cranial fossa. CPPs in the posterior cranial fossa have several features, including a propensity to arise at the foramen of Luschka with extraventricular extension, occasional peritumoral signal voids/cysts or calcification, weaker enhancement on MR or CT, and less strong tumor staining by the anterior or posterior inferior cerebellar artery or angiography.

Adolescent↗
PubMedDate not supplied

Spinal epidural cavernous hemangioma: MR findings.

PURPOSE: Cavernous hemangiomas with a spinal epidural location are very uncommon vascular tumors in contrast to those in the vertebral body. The purpose of this study was to describe the radiologic findings, focusing on the MR studies, of spinal epidural cavernous hemangiomas. METHOD: Five pathologically proven cases of spinal epidural cavernous hemangioma were retrospectively reviewed. MR (n = 5) and CT (n = 1) were evaluated. RESULTS: The level was thoracic (n = 4) or lumbosacral (n = 1). The mass was located in the epidural space and showed paravertebral extension in all cases. It showed a lobulated contour in all cases and encircled the spinal cord partially with a larger posterior (n = 3) or anterior (n = 1) component in four cases. In all cases, the mass showed high signal intensity on T2-weighted images and homogeneous, strong enhancement. Adjacent bony erosion (n = 5) and intervertebral neural foraminal widening (n = 4) were common. CONCLUSION: Spinal epidural cavernous hemangioma shows characteristic MR findings of a lobulated contoured epidural mass partially encircling the spinal cord with a larger posterior component in the spinal canal, high signal intensity on T2-weighted images, and homogeneous, strong enhancement.

Adult↗