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Biomedical subjects

J Kim

Publications and source records attributed to J Kim.

At least 757 records · Page 42Linked to original sources
PubMed1997

Origin and distribution of NADPH diaphorase-positive nerves in rat nasal mucosa.

The aim of this study was to localize the distribution of (reduced) nicotinamide-adenine dinucleotide phosphate (NADPH) diaphorase-positive nerves in the rat nasal mucosa by NADPH diaphorase histochemistry, and to determine its origin by utilizing retrograde tracing with Fluoro-Gold (FG). Fine varicosities of NADPH diaphorase-positive nerve fibers were distributed around blood vessels (arterioles in particular), submucosal glands, and the subepithelial layer of the nasal mucosa. Most of the ganglion cells and nerve fibers in the sphenopalatine ganglion, and a few ganglion cells in the trigeminal ganglion, were stained by NADPH diaphorase, but no NADPH diaphorase-positive ganglion cells were found in the superior cervical ganglion. Retrograde tracing with FG and co-localization of NADPH diaphorase demonstrated that the FG-labeled ganglion cells in the sphenopalatine ganglion were NADPH diaphorase-positive, but the FG-labeled ganglion cells in both the trigeminal and the superior cervical ganglia were NADPH diaphorase-negative. In conclusion, NADPH diaphorase-positive nerves distribute around blood vessels, around submucosal glands, and in the subepithelial layer of the rat nasal mucosa, and their origin is the sphenopalatine ganglion. These findings imply that nitric oxide may be co-localized to the cholinergic innervation and be involved in vasomotor and secretomotor control of the nasal mucosa.

Animals↗
PubMed1997

A survey of the newborn populations in Belgium, Germany, Poland, Czech Republic, Hungary, Bulgaria, Spain, Turkey, and Japan for the G985 variant allele with haplotype analysis at the medium chain Acyl-CoA dehydrogenase gene locus: clinical and evolutionary consideration.

Medium chain acyl-CoA dehydrogenase (MCAD) deficiency is an inborn error of fatty acid metabolism. It is one of the most frequent genetic metabolic disorders among Caucasian children. The G985 allele represented 90% of all the variant alleles of the MCAD gene in an extensive series of retrospective studies. To study the distribution of the G985 allele, newborn blood samples from the following countries were tested; 3000 from Germany (1/116). 1000 each from Belgium (1/77). Poland (1/98), Czech Republic (1/240). Hungary (1/168), Bulgaria (1/91), Spain (1/141). Turkey (1/216), and 500 from Japan (none). The frequency is shown in parentheses. The haplotype of G985 alleles in 1 homozygote and 57 heterozygote samples were then analyzed using two intragenic MCAD gene polymorphisms (Iaq1 and GT-repeat). The result indicated that only 1 of the 10 known haplotypes was associated with the G985 mutation, suggesting that G985 was derived originally from a single ancestral source. We made a compilation of the G985 frequencies in these countries and those in nine other European countries studied previously. The G985 distribution was high in the area stretching from Russia to Bulgaria in the east and in all northern countries in western and middle Europe, but low in the southern part of western and middle Europe. The incidence among ethnic Basques appeared to be low. This distribution pattern and the fact that all G985 alleles belong to a single haplotype suggest that G985 mutation occurred later than the delta F508 mutation of the CFTR, possibly in the neolithic or in a later period, and was brought into Europe by IndoEuropean-speaking people. The panEuropean distribution of the G985 allele, including Slavic countries from which patients with MCAD deficiency have rarely been detected, indicates the importance of raising the level of awareness of this disease.

Acyl-CoA Dehydrogenases↗
PubMed1997

Growth hormone response to the hypothalamic somatostatinergic activity in acromegalic patients.

Oral glucose administration suppresses the TRH-induced TSH response by enhancing the hypothalamic somatostatinergic activity (HSA). We assessed the HSA in 13 acromegalic patients by measuring glucose-induced suppression of TRH-stimulated TSH secretion. The HSA showed wide variation with up to 64% suppression. The mean HSA of the patients (25 +/- 6%) did not differ from that in normal young men (19 +/- 4%) in our previous study. Six patients had normal or low HSA, and the other 7 patients had high HSA. The mean TRH-stimulated TSH levels of the patients with normal or low HSA was significantly lower than that of the patients with high HSA (5.13 +/- 0.10 vs. 11.30 +/- 2.80 mU/L). The HSA did not relate to sex, age, tumor size, basal GH levels, the paradoxical responses to TRH and GnRH, octreotide response, or the gsp oncogene. In the combined glucose-TRH test, glucose pretreatment completely suppressed the paradoxical increase in GH level at 30 min in 4 patients. However, it could suppress the paradoxical GH response by only 6-51% in the other 5 patients who also showed the paradoxical response in TRH test. The tumor diameter of patients with good response to the HSA was significantly larger than that of the patients with poor response (31 +/- 5 vs. 14 +/- 2 mm) as was the tumor grade (3.3 +/- 0.3 vs. 1.7 +/- 0.2). This study supports the idea that a reduction of HSA is not a primary cause of acromegaly, and the HSA seems to increase to suppress the autonomous secretion of GH from the pituitary adenomas. HSA as well as the response of tumors to HSA do not determine tumor growth.

Acromegaly↗
PubMed1997

Immunocytochemical analysis of peptide hormone processing: importance of the positively charged N-terminal domain of signal peptide in correct ER targeting in yeast cells.

We used a morphological approach to determine the topogenic role of the signal peptide in mediating the ER translocation of yeast prepro-alpha-factor. In prepro-alpha-factor-somatostatin hybrids, changes in the N-terminal amino acid sequence from wild-type NH2-Met-Arg-Phe (MRF) to NH2-Met-Phe-Lys (MFK) caused a subtle difference in protein trafficking in yeast cells. Immunofluorescence microscopy on semithin cryosections and immunoelectron microscopy on ultrathin sections showed that the transposition of the charged amino acid at N-terminus caused the precursors to be associated with either nucleus or mitochondria. This suggests that the secretory proteins are mistargeted to the irrelevant organelles as the result of inefficient ER translocation. Structural aspects of nuclear or mitochondrial targeting proteins and common principles in membrane translocation systems account for the mistargeting of overexpressed mutant hybrid precursors that are not rapidly translocated into the ER. Based on our immunocytochemical study on individual cells, we propose here that the positively charged N-terminal domain of signal peptide is important not merely in the efficiency of ER translocation, but also in appropriate targeting of peptide hormone precursors in yeast cells where post-translational ER translocation is known to occur frequently.

Biological Transport↗
PubMed1997

Antifibrotic effects of a polysaccharide extracted from Ganoderma lucidum, glycyrrhizin, and pentoxifylline in rats with cirrhosis induced by biliary obstruction.

For the past few years, we have been investigating polysaccharides from Ganoderma lucidum as antifibrotic agents. In a previous study, we discovered that polysaccharides extracted from G. Iucidum lowered the collagen content in liver but had no effect on serum biochemical parameters in rats subjected to bile duct ligation and scission-induced fibrosis. In this study, we changed the extraction method and obtained polysaccharides extracted from G. Iucidum. The polysaccharide from G. Iucidum reduced the serum aspartate transaminase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP) and total bilirubin and also reduced the collagen content in liver and improved the morphology. Pentoxifylline, which is reported to exhibit an antifibrotic effect in pigs with fibrosis induced by yellow phosphorus, did not have any antifibrotic effects in fibrosis induced by biliary obstruction. Glycyrrhizin, which is used in the treatment of hepatitis, reduced serum ALT and AST values but there was no significance. It had no effect on liver hydroxyproline content which implies that glycyrrhizin has no antifibrotic effect in the rats with fibrosis induced by bile duct ligation and scission. These data suggest that the polysaccharide from Ganoderma lucidum could be a promising antifibrotic agent. However, further study is needed to understand the inhibition mechanism of collagen deposition of polysaccharides from Ganoderma Iucidum and its clinical applicability remains to be established.

Animals↗
PubMed1997

Antiviral substance from silkworm faeces: purification and its chemical characterization.

In a previous paper, we reported that an extract of silkworm faeces has a marked antiviral activity on enveloped viruses, but not on a non-enveloped virus, and we showed that it inhibits the synthesis of a viral specific gene of HVJ (Sendai virus) without affecting the viral adsorption and entry into the host cell. In this paper, we accomplished the purification of an antiviral active substance by extraction of a hydrophobic substance and thin layer chromatography. The active substance was found to be a chlorophyll-like substance with a molecular mass of about 530. This substance shows clear antiviral activity against HVJ, HSV (herpes simplex virus type-1), and HIV (human immunodeficiency virus type-1). Its antiviral activity was dependent on light irradiation and temperature. Furthermore, it also possesses a strong hemolytic activity under light.

Animals↗
PubMed1997

Pancreatic islet expression studies and polymorphic DNA markers in the genes encoding hepatocyte nuclear factor-3alpha, -3beta, -3gamma, -4gamma, and -6.

The genes encoding the functionally related hepatocyte nuclear factors HNF-1alpha and HNF-4alpha play a critical role in normal pancreatic beta-cell function. Mutations in these liver-enriched transcription factors result in two forms of early-onset type 2 diabetes (maturity-onset diabetes of the young [MODY]), MODY3 and MODY1, which are characterized by impaired glucose-stimulated insulin secretion, early disease onset, and autosomal dominant inheritance. The transcriptional hierarchy of HNFs suggests that other proteins of the regulatory cascade might be responsible for other forms of MODY and/or late-onset type 2 diabetes. In this study, we show that HNF-3alpha, -3beta, -3gamma, -4gamma, and -6 are expressed in pancreatic beta-cells. We report the identification and characterization of simple tandem repeat DNA polymorphisms in the genes encoding HNF-3alpha, -3beta, -3gamma, -4gamma, and -6 and the mapping of HNF-6 to chromosome bands 15q21.1-21.2 by fluorescence in situ hybridization. These markers will be useful to study the role of genetic variation in these genes in the pathogenesis of type 2 diabetes.

Base Sequence↗
PubMed1997

Aspergillus nidulans infection in a patient with chronic granulomatous disease.

Aspergillus nidulans is one of the several species of Aspergillus with low pathogenicity. The significant infections of A. nidulans in human have rarely been reported, almost exclusively in patients with chronic granulomatous disease (CGD). CGD is a primary immunodeficiency disease which results from the absence of the NADPH oxidase in the phagocytic cells, leading to recurrent pyogenic infection and granuloma and abscess formation. Here we report a fatal case A. nidulans infection in a six-year-old boy with chronic granulomatous disease. A. nidulans was isolated from the culture of a paraspinal abscess and Aspergillus was detected in the surgical tissue by in situ hybridization. The patient succumbed despite prolonged treatment with high-dose amphotericin B, itraconazole and interferon-alpha. To our knowledge, this is the first report of A. nidulans infection in Korea.

Aspergillosis↗
PubMed1997

Reconstitution of class I MHC molecules expressed in E. coli and complexed with single antigenic peptides.

The HLA-Cw3 heavy chain has been expressed at high level as insoluble protein aggregates in E. coli. The protein aggregates dissolved in strong denaturant solution were efficiently reconstituted by removal of denaturant in the presence of an HLA-Cw3 binding peptide (FAM) and beta 2m. The reconstituted HLA-Cw3/FAM protein binds specifically to a p58 natural killer cell inhibitory receptor, a natural ligand. The HLA-A2 molecule has also been reconstituted in complex with either of a peptide from myelin associated glycoprotein (MAG) or a peptide from the GAG protein of human immunodeficiency virus. The HLA-A2/MAG protein crystallized under the identical conditions as HLA-A2 purified from human lymphoblastoid cells. The reconstitution method has yielded an abundant supply of HLA molecules complexed with single antigenic peptides, and may be of general utility in reconstituting any class I MHC molecules. However, the HLA molecules could not be reconstituted either without a peptide or with an irrelevant peptide. Using this property, the reconstitution method could be used to determine whether a peptide is restricted/bound to certain class I MHC molecule.

Crystallization↗
PubMed1997

CNS innervation of the urinary bladder demonstrated by immunohistochemical study for c-fos and pseudorabies virus.

The aim of the present study is to verify the functional and anatomical neural pathways which innervate the urinary bladder in the central nervous system of the rat. To identify the functional neural pathway, the urinary bladder was stimulated by infusing formalin for 2 h. Then, brain and spinal cord were dissected out and immunohistochemistry was done by using anti-c-fos antibody. Many c-fos immunoreactive (IR) neurons were identified in the telencephalic cortical areas and in several brainstem nuclei, which are known mostly to be related with urinary bladder. In the spinal cord, a number of c-fos IR neurons were found in the lamina I, IIo, dorsal gray commissure, sacral parasympathetic nucleus. To identify the anatomical neural pathway of the urinary bladder, Pseudorabies virus (PRV) was injected into the wall of urinary bladder and was identified with anti-PRV by using immunohistochemistry. Most PRV labeled neurons were found where c-fos IR neurons were identified and few of them were also in the areas where c-fos IR neurons were not found, e.g., prefrontal cortex, agranular insular cortex, and subfornical organ. In the spinal cord, PRV labeled cells were found all over the gray matter. The present study presents morphological evidence demonstrating the supraspinal areas are related with the neural control of the urinary bladder and most functional neural pathway of the urinary bladder is well consistent with the anatomical neural pathway except in some telencephalic cortical areas.

Animals↗
PubMed1997

Live female Enterobius vermicularis in the posterior fornix of the vagina of a Korean woman.

A 33-year-old Korean woman, para 2. visited an obstetrics and gynecology clinic, Kumi-shi, Kyongsangbuk-do, due to postcoital spotting and flank pain. She had a tubal ligation 7 years before and demonstrated back pain during menstruation. She revealed a foul smelling discharge without complaint of itching. Enterobius vermicularis eggs were demonstrated during microscopic examination of a smear taken from the posterior fornix of the vagina. On endoscopic examination of her vagina, a live worm was found in the posterior fornix. The worm was removed and identified as a female E. vermicularis based on morphology. This is the first case report of vaginal enterobiasis in Korea.

Adult↗
PubMed1997

Traumatic auricular hematoma: a case report.

Traumatic recurrent auricular hematoma can be a challenging medical problem, with complications resulting in cauliflower ear. Proper management often depends on an understanding of the pathophysiology and pathogenesis of fibroneocartilage--an abnormal fibrous cartilage formation in response to injury. Traditional treatment by incision and drainage, and compression dressing technique may be inadequate in the setting of recurrent or chronic hematoma. Instead, excision of the fibroneocartilage is essential in promoting hematoma resolution and wound healing. Appropriate treatment of auricular hematoma can reduce needless cosmetic deformity and can avoid difficult secondary reconstruction. The authors present a case of recurrent auricular hematoma and review its pathophysiology and current therapy.

Bandages↗
PubMed1997

Biomarkers of squamous cell carcinoma of the head and neck.

Despite the remarkable advances in cancer treatment, the 5-year survival rate for head and neck squamous cell carcinoma (HNSCC) has improved only marginally over the past 20 years. Investigators have attempted to develop new therapeutic methods to improve the survival rate from these tumors. Another approach, chemoprevention, has recently been tried to reduce cancer incidence. Biological understanding of tumorigenesis is critically important to provide risk assessment and intermediate end points during chemoprevention trials. Based on the fact that HNSCC develops through a multistep process by the accumulation of genetic and phenotypic changes in the field exposed to carcinogens, the investigation of specific biomarkers that represent each step must be valuable, since these biomarkers could be used to inhibit and/or to reverse the pathway of carcinogenesis. The potential biomarkers are classified as nonspecific and specific genetic biomarkers, proliferation markers, and differentiation markers in this review. Their usefulness in predicting tumors' biological behavior and responses to treatment and in monitoring the preventive effects of chemoprevention trials is also discussed.

Biomarkers, Tumor↗
PubMed1997

Regulation of uveal sympathetic neurotransmission by peroxides.

PURPOSE: To investigate the effect of naturally occurring and synthetic peroxides on norepinephrine release from isolated iris-ciliary bodies of several mammalian species. METHODS: Hemiirides (bovine) and iris-ciliary bodies (human, rabbit, and rat) were incubated in Krebs solution containing [3H]-norepinephrine ([3H]NE) for 60 minutes. After incubation, tissues were set up for studies of [3H]NE release using the superfusion method. Release of [3H]NE was elicited through electrical field stimulation. RESULTS: In bovine irides, hydrogen peroxide (H2O2), cumene hydroperoxide (cuOOH), and tert-butyl hydroperoxide (buOOH) caused a concentration-dependent potentiation of field-stimulated [3H]NE release with the following rank order of potency: cuOOH > H2O2 > buOOH. Furthermore, the free radical scavenger, melatonin (2 mM), prevented the enhancement of evoked [3H]NE overflow elicited by H2O2 and cuOOH. At equimolar concentrations, H2O2 (1 mM) increased stimulated [3H]NE release from rabbit, human (mean age, 29.7; range, 15 to 48 years), and Fischer 344 rat (4 months old) iris-ciliary bodies by 98%, 50%, and 40%, respectively. However, H2O2 (1 mM) caused a 9% increase in evoked [3H]NE release in tissue from aged Fischer 344 rats (30 months old) and a 5% decrease in neurotransmitter release in tissue from old human donors (mean age, 72.3 years; range, 69 to 74 years). CONCLUSIONS: Peroxides such as H2O2 can potentiate sympathetic neurotransmission in the anterior uvea of several mammalian species. In bovine irides, H2O2-induced enhancement of neurotransmitter release can be mimicked by synthetic peroxides and may involve the generation of reactive oxygen species.

Adolescent↗
PubMed1997

Myogenin expression is necessary for commitment to differentiation and is closely related to src tyrosine kinase activity in quail myoblasts transformed with Rous sarcoma virus.

Quail myoblasts transformed with a temperature-sensitive mutant of Rous sarcoma virus (QM-RSV cells) proliferate at 35.5 degrees C, a permissive temperature for RSV, but differentiate at 41 degrees C, a nonpermissive temperature, with the formation of multinucleated myotubes and the synthesis of muscle-specific proteins. Tyrosine kinase activity of the src gene product derived from RSV is closely related to regulation of this temperature-dependent differentiation, and the cells obtain commitment to differentiation by incubation for about 12 h at 41 degrees C with dephosphorylation of tyrosine-phosphorylated protein(s). It was examined how myogenin, a member of myogenic regulatory factors, participates in commitment to differentiation and tyrosine dephosphorylation of QM-RSV cells. Myogenin was expressed within 8 h and reached a plateau within 10 h at 41 degrees C. Each cell clone whose differentiation proceeded faster or slower than the parental QM-RSV cells was reflected by a faster or slower myogenin expression, corresponding to the time that is required for commitment to differentiation. It was suggested that there is a lag time between myogenin expression and the acquisition of commitment in QM-RSV cells. On the other hand, at 35.5 degrees C, a condition which suppresses differentiation, myogenin expression was not detected. However, herbimycin A, an inhibitor of protein tyrosine kinase, induced myogenin expression even at 35.5 degrees C. On the contrary, myogenin expression was inhibited at 41 degrees C by sodium orthovanadate, an inhibitor of tyrosine-phosphorylated protein phosphatase. Furthermore, forced induction of myogenin into the cells cultured at 35.5 degrees C resulted in the formation of multinucleated myotubes and the synthesis of muscle-specific proteins. These results suggest that myogenin expression is one of the indispensable conditions for the acquisition of commitment to differentiation and is regulated by tyrosine phosphorylation and dephosphorylation of some protein(s) in QM-RSV cells.

Animals↗
PubMed1997

Angiocentric T cell lymphoma of the skin presenting as inflammatory nodules of the leg.

We describe two cases of malignant lymphoma presenting as inflammatory nodules of the leg and mimicking panniculitis clinically. In both cases the skin biopsies showed prominent involvement of the subcutaneous tissue by lymphoma cells. In addition, lymphoma cells invaded blood vessels in the dermis or the subcutaneous tissue. One case was characterized by predominantly extravascular and intravascular location of the lymphoma cells, and the other case by the predominantly extravascular and intramural location of lymphoma cells. These histological findings were compatible with those of angiocentric T-cell lymphoma but with some unusual features. Angiocentric T-cell lymphoma of the skin should be listed in the group of diseases which present as inflammatory nodules of the leg.

Adult↗