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Won C, Park HJ, Shin HC. Interleukin-1 beta facilitates afferent sensory transmission in the primary somatosensory cortex of anesthetized rats. Neurosci Lett 1995; 201:255-8. [PMID: 8786853 DOI: 10.1016/0304-3940(95)12185-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The effect of topical application of human recombinant interleukin-1 beta (IL-1) on afferent sensory transmission to the neurones in the primary somatosensory (SI) cortex was determined in anesthetized rats. Quantitative determination of the effect of IL-1 was made by generating post-stimulus time histograms of unit responses to the stimulation of receptive field. IL-1 (0.01, 0.1, 1.0 U) significantly facilitated afferent sensory transmission in SI cortical neurones (n = 22). IL-1-induced facilitation fully recovered by 60 min after drug. In control experiments (n = 10), saline solution containing 0.2 bovine serum albumin, used as a vehicle, did not affect afferent sensory transmission. Our results suggest that IL-1 may be involved in the processing of afferent sensory information in the SI cortex of rats.
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352
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Park HJ, Rhee MH, Park KM, Nam KY, Park KH. Effect of non-saponin fraction from Panax ginseng on cGMP and thromboxane A2 in human platelet aggregation. JOURNAL OF ETHNOPHARMACOLOGY 1995; 49:157-162. [PMID: 8824741 DOI: 10.1016/0378-8741(95)01317-2] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The non-saponin fraction (NSF; lipophilic fraction) from the roots of Panax ginseng inhibited the aggregation of human platelets induced by thrombin (0.1 units/ml) in a dose-dependent manner. NSF induced the elevation of cGMP concentration in human platelets in a similar manner to molsidomine, a known vasodilator. NSF also inhibited Ca(2+)-influx into platelets. While verapamil, a Ca(2+)-antagonist, increased the cAMP level in platelets stimulated by thrombin, NSF had little effect on cAMP formation. Instead, NSF potently inhibited the thromboxane A2 (TXA2) production. The results suggest that NSF may regulate the levels of cGMP and TXA2 to inhibit platelet aggregation induced by thrombin.
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353
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Abstract
The nature of the endonucleases responsible for DNA fragmentation in apoptosis has not yet been clearly defined. The intracellular acidity has been known to greatly affect apoptosis probably by affecting the activity of the endonucleases. In this study, the implication of pH in the apoptosis was investigated through the use of human HL-60 leukemia cells. The cells were incubated in media with different pH ranging from 3.5 to 7.5 for 4 hrs and the mode of cell death was investigated. The trypan blue exclusion assay showed that close to 25% and 90% of the cells were dead when incubated in pH 6.4 and pH 5.0 media, respectively. The agarose gel electrophoresis of DNA demonstrated that significant DNA fragmentation occurred in the HL-60 cells incubated in the pH 6.2-6.4 media for 4 hr indicating cell death by apoptosis. The electron microscopy study also demonstrated that many of the cells incubated in the pH 6.4 medium were in the process of apoptosis while the cells maintained in the pH 5.0 medium were dying by necrosis. The intracellular pH (pHi) of HL-60 cells was 6.6-6.9 when the extracellular pH (pHe) was 6.2-6.4. These results demonstrated that DNase I which has a maximal endonuclease activity near pH 7.0 may be responsible for the apoptosis accompanied by DNA fragmentation in HL-60 cells in the pH 6.4 medium. This observation is at variance with the previous reports that DNase II mediate the DNA fragmentation in apoptosis. The cell death at extremely low pH (pH 5.0) appeared to be due mainly to necrosis.
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Abstract
PURPOSE To document the proctographic features of anismus at evacuation proctography and determine the optimum radiologic measurements for diagnosis. MATERIALS AND METHODS Twenty-four patients with anismus according to clinical and multiple physiologic criteria were examined with evacuation proctography. Structural and functional measurements were compared with those of a group of 20 asymptomatic subjects. RESULTS No significant difference between patients and control subjects was found with respect to pelvic descent, rectocele, or any anorectal angle measurement. In patients with anismus, initiation of evacuation was prolonged (median, 9 vs 3 seconds for control subjects; P < .0001) and anal canal width was reduced (median, 0.6 vs 1.2 cm; P = .0075). Evacuation time was increased (median, 50 vs 10 seconds; P < .0001), and the percentage of contrast material evacuated was decreased (median, 60% vs 100%; P < .0001). Only four patients were able to evacuate more than 66% of the contrast material within 30 seconds, whereas all control subjects were able to do so. CONCLUSION Measurement of the anorectal angle to diagnose anismus should be abandoned. Patients with anismus demonstrate delayed initiation of evacuation, which is also prolonged and incomplete. Incomplete evacuation after 30 seconds is highly suggestive of anismus.
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355
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Hecht HJ, Erdmann H, Park HJ, Sprinzl M, Schmid RD. Crystal structure of NADH oxidase from Thermus thermophilus. NATURE STRUCTURAL BIOLOGY 1995; 2:1109-14. [PMID: 8846223 DOI: 10.1038/nsb1295-1109] [Citation(s) in RCA: 83] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The crystal structures of the flavin adenine dinucleotide (FAD) and flavin mononucleotide (FMN) containing isoforms of NADH oxidase from Thermus thermophilus have been determined by isomorphous and molecular replacement and refined to 2.3 A and 1.6 A resolution with R-values of 18.5% and 18.6% respectively. The structure of the homodimeric enzyme consists of a central 4-stranded antiparallel beta-sheet covered by helices, a more flexible domain formed by two helices, and a C-terminal excursion connecting the subunits. The active sites are located in a deep cleft between the subunits. The binding site of the flavin cofactor lacks the common nucleotide binding fold and is different from the FMN binding site found in flavodoxins.
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356
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Nah SY, Park HJ, McCleskey EW. A trace component of ginseng that inhibits Ca2+ channels through a pertussis toxin-sensitive G protein. Proc Natl Acad Sci U S A 1995; 92:8739-43. [PMID: 7568008 PMCID: PMC41042 DOI: 10.1073/pnas.92.19.8739] [Citation(s) in RCA: 116] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
A crude extract from ginseng root inhibits high-threshold, voltage-dependent Ca2+ channels through an unknown receptor linked to a pertussis toxin-sensitive G protein. We now have found the particular compound that seems responsible for the effect: it is a saponin, called ginsenoside Rf (Rf), that is present in only trace amounts within ginseng. At saturating concentrations, Rf rapidly and reversibly inhibits N-type, and other high-threshold, Ca2+ channels in rat sensory neurons to the same degree as a maximal dose of opioids. The effect is dose-dependent (half-maximal inhibition: 40 microM) and it is virtually eliminated by pretreatment of the neurons with pertussis toxin, an inhibitor of G(o) and Gi GTP-binding proteins. Other ginseng saponins--ginsenosides Rb1, Rc, Re, and Rg1--caused relatively little inhibition of Ca2+ channels, and lipophilic components of ginseng root had no effect. Antagonists of a variety of neurotransmitter receptors that inhibit Ca2+ channels fail to alter the effect of Rf, raising the possibility that Rf acts through another G protein-linked receptor. Rf also inhibits Ca2+ channels in the hybrid F-11 cell line, which might, therefore, be useful for molecular characterization of the putative receptor for Rf. Because it is not a peptide and it shares important cellular and molecular targets with opioids, Rf might be useful in itself or as a template for designing additional modulators of neuronal Ca2+ channels.
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Park SH, Chung JP, Kim IJ, Park HJ, Lee KS, Chon CY, Park IS, Kim KW, Lee DY. Dysphagia due to mediastinal tuberculous lymphadenitis presenting as an esophageal submucosal tumor: a case report. Yonsei Med J 1995; 36:386-91. [PMID: 7483683 DOI: 10.3349/ymj.1995.36.4.386] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Mediastinal tuberculous lymphadenitis is rare in adults, and it is even rarer for dysphagia to be the presenting symptom of mediastinal tuberculous lymphadenitis. Mediastinal tuberculous lymphadenitis with esophageal symptoms has been presented as esophageal ulceration, mucosal or submucosal mass with ulceration, fistula or sinus formation, extrinsic compression, or displacement of the esophagus. An exaggerated form of extrinsic compression may be presented as a submucosal tumor, radiologically or endoscopically. A barium esophagography of a 34 year-old woman with painful dysphagia revealed a large submucosal tumor-like mass on the mid-esophagus. The symptom was spontaneously improved over a 3-week period together with reduction of the mass size. A computed tomography of the chest disclosed an enlarged subcarinal lymph node and histologic examination of the specimen obtained by thoracoscopic biopsy brought about a diagnosis of tuberculosis. We herein report a case of mediastinal tuberculosis with unusual manifestations.
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Abstract
Sixteen children of uncontrollable fecal incontinence have been treated with Pickrell's gracilis muscle transposition since 1983: 12 had an imperforate anuses with multiple corrective operative procedures and 4 had traumatic destructions of anal sphincters. We report a series of 11 cases whom we followed-up over a period of 0.8 to 10.5 years (mean; 5.6 years). Seven patients were evaluated by anorectal manometry. All patients except one who had left hemipelvectomy and permanent colostomy showed nearly normal continence during the follow-up period. There was no evidence of fibrosis in the transposed muscles and the tensions of the transposed muscles were well maintained. The voluntary contractions of the transposed muscles were well maintained and efficient in all cases. The general manometric parameters did not correlate well with the functional results; however, there was a strong correlation in the S/R ratio (maximum squeeze pressure/resting pressure) with the functional results. We believe that the good functional outcome of this procedure need not only the meticulous surgical technique but also the personal motivation and the compliance with physiotherapy. In conclusion, although the gracilis muscle transposition never results in normal continence, acceptable continence can be achieved in the selected patients.
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Abstract
Abdominal cocoon is a rare disease of the peritoneum and almost invariably presents as an acute or subacute intestinal obstruction with or without a mass. The etiology of this disease is largely unknown and abdominal cocoon of unknown etiology has been limited to the tropical and subtropical zones and primarily affects young adolescent females. In the temperate zone, only one case has been reported from the United Kingdom, but the patient was also born in Pakistan. No case of abdominal cocoon purely developed in the temperate zone has been reported. Recently, we experienced a case of abdominal cocoon in a 34-year-old female patient(Korean) who had never been abroad. The diagnosis was made postoperatively by reviewing the literature. We herein report this rare condition developed in an unusual geographical location with a brief review of the literature.
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Park HJ, Won CK, Pyun KH, Shin HC. Interleukin 2 suppresses afferent sensory transmission in the primary somatosensory cortex. Neuroreport 1995; 6:1018-20. [PMID: 7632885 DOI: 10.1097/00001756-199505090-00017] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The effect of topical application of interleukin 2 (IL-2) on afferent sensory transmission to the neurones in the primary somatosensory (SI) cortex was determined quantitatively in anaesthetized rats. IL-2 (0.1, 1.0, 5.0 units) significantly suppressed afferent sensory transmission in SI cortical neurones (n = 19) in a dose-dependent manner. IL-2-induced suppression fully recovered by 60 min after drug. In control experiments, saline solution containing 0.2% bovine serum albumin, used as a vehicle, did not affect afferent sensory transmission. Our results suggest that IL-2 and its receptor present in the SI cortex may be involved in the processing of afferent sensory information.
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361
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Park HJ, Kamm MA, Abbasi AM, Talbot IC. Immunohistochemical study of the colonic muscle and innervation in idiopathic chronic constipation. Dis Colon Rectum 1995; 38:509-13. [PMID: 7736882 DOI: 10.1007/bf02148851] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
PURPOSE This study was designed to investigate neural and muscular features of the colonic wall in patients with severe idiopathic constipation. METHODS By using quantitative immunohistochemistry, resected specimens from 14 patients with idiopathic chronic constipation and 17 nonobstructed cancer controls were studied. RESULTS Routine histology revealed no significant histologic abnormality throughout the colon apart from four cases of melanosis coli. Ratio of the thickness of circular to longitudinal muscle was significantly lower in the left colon in constipated subjects. The myenteric plexus appeared morphologically normal in all subjects. S-100 protein, which stains neuronal supporting tissues, demonstrated an increase in the proportion of neural tissue in the myenteric plexus. There was an increased number of PGP-9.5 immunoreactive nerve fibers in the muscularis propria in constipated patients, and this was significantly higher in the ascending and descending colon. CONCLUSION Intractably constipated patients have alterations in the neural composition of the colonic myenteric plexus and innervation of the circular muscle.
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362
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Park HJ, Kim HN. Central projection of the peripheral cochlear nerve from each turn to the cochlear nuclei in the Mongolian gerbil. Yonsei Med J 1995; 36:111-5. [PMID: 7618358 DOI: 10.3349/ymj.1995.36.2.111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
The central projections of the peripheral cochlear nerve fiber from each turn to the cochlear nuclei (CN) in the mongolian gerbil were investigated using retrograde transportation of horseradish peroxidase (HRP). The organ of Corti and the osseous spiral lamina were scratched with an electrolytically-sharpened fine needle via a small hole at each turn of the cochlea. The cochlea was filled with a 30% horseradish peroxidase (HRP) solution. After 48 hours, 50 microns transverse serial sections of the brainstem were made with a vibratome. The tissue was processed with the diaminobenzidine procedure of the cobalt-glucose method. Our experiment revealed that the fibers from the basal turn terminated at the dorsomedial portion of anteroventral cochlear nuclei (AVCN), but those from the apical turn were distributed among the ventrolateral portion of the AVCN. In the posteroventral cochlear nuclei (PVCN) and dorsal cochlear nuclei (DCN), the fibers from basal to apical turns extend from the dorsal to the ventral portion of each nuclei. A distinct tonotopic arrangement could be found between the origin of cochlear fibers of each turn and their termination in the regions of the cochlear nuclei (CN). Also, the results suggested that the scratch method combined with retrograde transportation of horseradish peroxidase was useful in investigating the tonotopic arrangement of the peripheral auditory nerve in the CN.
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363
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Park HJ, Lee YL, Kwon HY, Suh SW, Yon JH. Pancreatic exocrine secretion in response to median raphe stimulation in anesthetized rats. Pancreas 1995; 10:407-12. [PMID: 7792298 DOI: 10.1097/00006676-199505000-00014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
To investigate a possible role of the central serotonergic system in the central control of pancreatic exocrine secretion, the median raphe nucleus of the anesthetized rat was electrically stimulated. The parameters of the biphasic square wave stimulus were 2 V, 2 ms, and 40 Hz. Electrical stimulation of the median raphe nucleus for 10 min resulted in large increases in pancreatic volume flow and protein output. The pancreatic responses were completely abolished by spinal cord transection at the level between C4 and C5. Cervical vagotomy or adrenalectomy failed to attenuate the pancreatic responses. The median raphe stimulation evoked a remarkable elevation of the blood pressure of the carotid artery as well as the plasma concentrations of noradrenaline and adrenaline. The responses were also completely inhibited by spinal cord transection but unaffected by cervical vagotomy. Adrenalectomy blocked the elevation of the plasma concentration of adrenaline only. Noradrenaline, given intravenously, stimulated the pancreatic volume flow and protein output. The actions of noradrenaline were antagonized by propranolol but not by phentolamine. It is, therefore, concluded from the present study that the median raphe nucleus may play a stimulatory role in pancreatic exocrine secretion of anesthetized rats and that the stimulatory role is mediated via the sympathetic nervous system acting on beta-adrenoceptors.
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364
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Chung JP, Cho HG, Chon CY, Park HJ, Lee KS, Kang JK, Park IS, Kim KW. A large common bile duct stone migrated from the gallbladder through a cholecystohepaticodochal fistula: an unusual complication of Mirizzi syndrome type II. Yonsei Med J 1995; 36:206-13. [PMID: 7618367 DOI: 10.3349/ymj.1995.36.2.206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Mirizzi syndrome with a biliobiliary fistula (Mirizzi syndrome type II) is a rare complication of a long-standing gallbladder stone disease. It is even rarer for a gallbladder stone to migrate through a biliobiliary fistula into the common duct. We encountered this interesting complication of Mirizzi syndrome type II in an 86 year-old female patient. A large gallbladder stone migrated into, and impacted into the distal common bile duct through a cholecystohepaticodochal fistula. The stone was resistant to mechanical lithotripsy and was treated with biliary endoprosthesis and oral bile acids.
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365
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Park HJ, Byun SM, Ha YJ, Ahn JS, Moon HM. Identification of immunodominant epitopes in the core and non-structural region of hepatitis C virus by enzyme immunoassay using synthetic peptides. JOURNAL OF IMMUNOASSAY 1995; 16:167-81. [PMID: 7543117 DOI: 10.1080/15321819508013556] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Thirty-two synthetic peptides, components of the core and non-structural protein of Hepatitis C virus (HCV), were tested for their reactivities against antibodies in sera of healthy, HCV antibody positive of chronic liver disease patients. Among them, 8 of the core peptides, 4 of the NS4 peptides and 3 of the NS5 peptides reacted with the HCV infected sera. In particular, C22 (core peptide) and NS4-1924 (NS4 peptide) were most reactive with the serum samples giving a positive signal with commercially available enzyme-linked immunosorbent assay (ELISA) kit. Our results indicate that the immunodominant regions of the HCV-derived proteins are located at three regions in the core protein, three regions in the NS4 protein, and one region in the NS5 protein. These results indicate that the selected peptides are useful antigens in detecting antibodies in the sera from individuals infected with HCV.
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366
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Park HJ, Kim HN, Kim KM. Redistribution of facial nerve motor neurons after recovery from nerve crushing injury in the gerbil. Acta Otolaryngol 1995; 115:273-5. [PMID: 7610820 DOI: 10.3109/00016489509139307] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
We investigated the redistribution of facial motor neurons after recovery from a crush injury of the facial nerve in the mongolian gerbil, with the retrograde transportation of horseradish peroxidase (HRP) technique. The facial nerve at the vertical segment was crushed unilaterally for 10 s with forceps. After 1 month, movement of the vibrissae and blinking reflex were observed. Three months after nerve injury, we obtained the brainstems to investigate the distribution of the facial nerve motor neurons. On the normal side, motor neurons of the ophthalmic branch of the facial nerve were organized at the dorsomedial and dorsolateral subdivisions of the facial nucleus, and those of the superior buccal branch were distributed at intermediate and ventrolateral subdivisions of the facial nucleus in the brainstem. On the experimental side, instead of somatotopical organization, we found widespread irregular distribution of the motor neurons of both branches in the entire facial nucleus of the brainstem.
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367
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Abstract
Bombesin was intracisternally administered to determine the effects on the neuronal activities of the dorsal column nuclei (DCN) of anesthetized rats. Although averaged afferent somatosensory transmission through 22 DCN neurons did not appear to be altered by bombesin (-1.11 +/- 3.5%), 12 of them were actually augmented (+17.15 +/- 2.7%) and 10 of them were suppressed (-26.15 +/- 4.9%) during 40 min after bombesin (0.01 microgram) administration. Pretreatment of a bombesin antagonist ([Leu13,Psi(CH2NH)Leu14]bombesin, 0.1 microgram) blocked the effects of bombesin. Lower dose (0.001 microgram) of bombesin did not exert any influences. These results suggest that bombesin may heterogeneously influence afferent somatosensory information in the brain stem of the rat.
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368
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Park HJ, Youn DH. Quantitative analysis of changes of automated perimetric thresholds after pupillary dilation and induced myopia in normal subjects. KOREAN JOURNAL OF OPHTHALMOLOGY 1994; 8:53-60. [PMID: 7853732 DOI: 10.3341/kjo.1994.8.2.53] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
We quantitatively analyzed the changes of the (retinal) threshold sensitivities between normal status and dilated emmetropic status, and between dilated emmetropic status and -1.0D induced myopic status. Three consecutive visual field examinations by Humphrey Field Analyzer C-30-2 threshold test and STATPAC program were performed in 36 eyes of 21 normal subjects who ranged in age from 23 to 40 years. The results were as follows: 1) There was a statistically significant decrease (0.87 +/- 0.91dB)in the mean threshold sensitivity within the central 30 degrees at the dilated emmetropic status (27.90dB) as compared with the normal status (28.77dB)(p = 0.0001). 2) There was a statistically significant decrease(0.99 +/- 0.61dB) at -1.0D induced myopic status(26.91dB) as compared with the dilated emmetropic status(27.90dB)(p = 0.0001). 3) After dilation, the mean threshold sensitivity between 20 and 30 degrees of field showed statistically significant decrease as compared with those within the central 20 degrees of visual field(p < 0.05). In case of -1.0D induced myopia, there were uniform decreases in the mean threshold sensitivities within the central 30 degrees of visual field (p > 0.05). Therefore, we emphasize the importance of consistent pupillary size and correct refractive state in performing the serial automated visual field tests.
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369
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Shin HC, Park HJ, Raymond SA. Potentiation by capsaicin of lidocaine's phasic impulse block in isolated rat sciatic nerve. Pharmacol Res 1994; 30:73-9. [PMID: 7831197 DOI: 10.1016/1043-6618(94)80089-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Compound action potentials (CAPs) of A- and C-fibres were recorded from isolated sciatic nerves of the rat to determine whether lidocaine-induced phasic impulse block was affected by low doses of capsaicin. Preceding impulse activity produced phasic reductions of the amplitudes of both A- (5.7 +/- 1.3%) and C-CAPs (20.7 +/- 7.0%) in drug-free solution. Capsaicin alone (50 microM) did not change the activity-induced reductions of the heights of both CAPs (A-CAP: 6.2 +/- 1.7%, C-CAP: 22.3 +/- 8.0%). Lidocaine (100 microM) caused differential phasic blocks between the A-CAP (20.1 +/- 3.7%; n = 7) and the C-CAP (33.8 +/- 4.9% n = 7). Lidocaine's phasic impulse block was potentiated after 30 min of subsequent capsaicin administration (A-CAP: 40.6 +/- 4.7%, n = 7; C-CAP: 48.8 +/- 5.5% n = 9). Capsaicin's phasic potentiating effects were reversed after 30 min of washing. These results suggest that capsaicin may be a useful agent for the reversible potentiation of phasic impulse blockade by lidocaine.
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Shin HC, Park HJ, Raymond SA, Strichartz GR. Potentiation by capsaicin of lidocaine's tonic impulse block in isolated rat sciatic nerve. Neurosci Lett 1994; 174:14-6. [PMID: 7970146 DOI: 10.1016/0304-3940(94)90107-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Compound action potentials (CAPs) of A- and C-fibers were recorded from isolated sciatic nerves of the rat to determine whether tonic block of impulse conduction induced by lidocaine was affected by low doses of capsaicin. Capsaicin alone (50 microM) did not change the CAPs of either A- or C-fibers. Although the lower concentrations of capsaicin (5-30 microM) caused no change of the tonic blocking action of lidocaine, 30 min of 50 microM capsaicin administration did induce a significant potentiation of tonic block. Capsaicin's potentiating effects were partially reversed after 30 min of wash. These results suggest that capsaicin may be a useful agent for the potentiation of impulse blockade by lidocaine.
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Abstract
We report three cases of solitary rectal ulcer syndrome (SRUS). The diagnosis was established according to histopathologic criteria. But, the initial clinical diagnosis was carcinoma, non-specific ulcer and localized proctitis respectively. SRUS is considered as one of functional disorder in pelvic floor which might go underdiagnosed due to unfamiliar concept in Korea. So we should consider SRUS to be one of the differential diagnosis in cases of complaining anorectal symptoms.
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372
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Shin HC, Lee YL, Kwon HY, Park HJ, Raymond SA. Activity-dependent variations in conduction velocity of C fibers of rat sciatic nerve. Neurosci Res 1994; 19:427-31. [PMID: 8090372 DOI: 10.1016/0168-0102(94)90084-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Changes in the conduction velocity and subsequent conduction block were characterized following impulse activity in single C fibers of rat sciatic nerves. C fibers which had the same resting conduction velocities often exhibited quite different profiles of the activity-dependent latency change and/or conduction block following impulses. The results imply underlying variation among C fibers in the activity-dependent excitability changes, especially in the build-up and recovery of the hypoexcitable phases.
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Shin HC, Park HJ, Chapin JK. Differential phasic modulation of short and long latency afferent sensory transmission to single neurons in the primary somatosensory cortex in behaving rats. Neurosci Res 1994; 19:419-25. [PMID: 8090371 DOI: 10.1016/0168-0102(94)90083-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Single neurons were recorded in the forepaw area of the primary somatosensory (SI) cortex of awake rats during rest and running behavior. Locomotor step cycle dependent changes of the transmission of the short (4.5 +/- 0.1-10.5 +/- 0.1 ms, SEURs) and the long (10.6 +/- 0.6-28.5 +/- 2.3 ms, LEURs) latency evoked unit responses were tested by generating post-stimulus time histograms of these neurons' responses to stimulation through electrodes chronically implanted under the skin of the forepaw. Times of footfall were determined by way of frame-by-frame analyses of video recordings, and peri-footfall histograms were generated to differentiate a total of 55 SI cortical neurons into two types: footfall responsive (n = 37) and footfall unresponsive (n = 18) neurons. Peri-footfall gating patterns were determined for both types of cells. The SEURs and the LEURs showed significantly different phasic sensory modulation patterns. A major difference in sensory modulations between footfall responsive and footfall unresponsive cells was noted during the swing phase of the locomotor step cycle. In footfall responsive cells, the SEURs were suppressed most strongly just after footfall, while the LEURs were phasically suppressed following both footfall and footoff. The SEURs were disinhibited during the swing phase. In footfall unresponsive cells, the SEURs were tonically suppressed during the whole locomotor step cycle phases. However, the LEURs were phasically facilitated during the early swing phase.(ABSTRACT TRUNCATED AT 250 WORDS)
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374
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Park HJ, Kreutzer R. Expression cloning of the nox, mdh and ldh genes from Thermus species encoding NADH oxidase, malate dehydrogenase and lactate dehydrogenase. Appl Microbiol Biotechnol 1994; 40:676-81. [PMID: 7508721 DOI: 10.1007/bf00173328] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The Thermus thermophilus HB8 mdh and ldh genes and the T. aquaticus EP00276 nox and mdh genes encoding the biotechnologically important enzymes NADH oxidase (EC 1.6.99.3), malate dehydrogenase (EC 1.1.1.37) and lactate dehydrogenase (EC 1.1.1.27) were cloned on the basis of known sequences from related species using the polymerase chain reaction. The nox and mdh genes were directly placed under the control of regulatory expression elements from Escherichia coli. When the 5'-portions of the re-cloned nox gene and the mdh gene of T. thermophilus HB8 were simultaneously altered, enzyme yields of 18-42% of the total soluble cellular protein were obtained as compared to 2-6% obtained from the unchanged genes. The high overproduction level upon the alterations can be explained by the occurrence of additional potential base pairs between nucleotides in the mRNA downstream of the start codon ('downstream box') and the 16S rRNA. An 'universal translation initiation sequence' providing such strong interactions may be of general use for high overproduction levels.
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Sun D, Park HJ, Hurley LH. Alkylation of guanine and cytosine in DNA by bizelesin. Evidence for a covalent immobilization leading to a proximity-driven alkylation of normally unreactive bases by a (+)-CC-1065 cross-linking compound. Chem Res Toxicol 1993; 6:889-94. [PMID: 8117929 DOI: 10.1021/tx00036a020] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Bizelesin, an intrahelical DNA-DNA interstrand cross-linker related to (+)-CC-1065, has been shown to alkylate DNA through guanine in restriction enzyme sequences in which there is a suitably positioned adenine contained in a highly reactive monoalkylation sequence on the opposite strand. Oligomers containing the sequence 5'-TTTTTN*, in which "N" was either G, C, or T, were synthesized to evaluate the cross-linking potential of bizelesin at nonadenine bases. Kinetic analysis of monoalkylation and cross-linking events demonstrates that it is the reaction at "N" (guanine or cytosine) that results in the cross-link which is the slow step. On the basis of this analysis and the normal unreactivity of guanine and cytosine to alkylation by the cyclopropapyrroloindole alkylating moiety of (+)-CC-1065, we propose that the molecular mechanism for this type of cross-linking reaction most likely involves a covalent immobilization of the second alkylating arm, resulting in a "proximity-driven" reaction.
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