• Title/Summary/Keyword: Spontaneous Reduction

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Nitric Oxide Modulation of GABAergic Synaptic Transmission in Mechanically Isolated Rat Auditory Cortical Neurons

  • Lee, Jong-Ju
    • The Korean Journal of Physiology and Pharmacology
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    • v.13 no.6
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    • pp.461-467
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    • 2009
  • The auditory cortex (A1) encodes the acquired significance of sound for the perception and interpretation of sound. Nitric oxide (NO) is a gas molecule with free radical properties that functions as a transmitter molecule and can alter neural activity without direct synaptic connections. We used whole-cell recordings under voltage clamp to investigate the effect of NO on spontaneous GABAergic synaptic transmission in mechanically isolated rat auditory cortical neurons preserving functional presynaptic nerve terminals. GABAergic spontaneous inhibitory postsynaptic currents (sIPSCs) in the A1 were completely blocked by bicuculline. The NO donor, S-nitroso-N-acetylpenicillamine (SNAP), reduced the GABAergic sIPSC frequency without affecting the mean current amplitude. The SNAP-induced inhibition of sIPSC frequency was mimicked by 8-bromoguanosine cyclic 3',5'-monophosphate, a membrane permeable cyclic-GMP analogue, and blocked by 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide, a specific NO scavenger. Blockade of presynaptic $K^+$ channels by 4-aminopyridine, a $K^+$ channel blocker, increased the frequencies of GABAergic sIPSCs, but did not affect the inhibitory effects of SNAP. However, blocking of presynaptic $Ca^{2+}$ channels by $Cd^{2+}$, a general voltage-dependent $Ca^{2+}$ channel blocker, decreased the frequencies of GABAergic sIPSCs, and blocked SNAP-induced reduction of sIPSC frequency. These findings suggest that NO inhibits spontaneous GABA release by activation of cGMP-dependent signaling and inhibition of presynaptic $Ca^{2+}$ channels in the presynaptic nerve terminals of A1 neurons.

Calcium Ions are Involved in Modulation of Melittin-induced Nociception in Rat: II. Effect of Calcium Chelator

  • Shin, Hong-Kee;Lee, Kyung-Hee;Cho, Chul-Hyun
    • The Korean Journal of Physiology and Pharmacology
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    • v.10 no.6
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    • pp.297-302
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    • 2006
  • Melittin, a major component of bee venom, produces a sustained decrease in mechanical threshold, and an increase in spontaneous flinchings and paw thickness, which are characteristics similar to those induced by whole bee venom. Melittin-induced nociception has been known to be modulated by the changes in the activity of excitatory amino acid receptors, voltage-dependent calcium channels, cyclooxygenase and serotonin receptors. The present study was undertaken to investigate the role of calcium chelators (TMB-8 & Quin 2) in melittin-induced nociceptive responses. Changes of mechanical threshold and spontaneous flinching behaviors were measured at a given time point following intraplantar injection of melittin ($30{\mu}g/paw$). Intrathecal or intraplantar pre-administration and intrathecal posttreatment of TMB-8 and Quin 2 significantly prevented the melittin-induced reduction of mechanical threshold, and intraplantar or intrathecal pre-treatment of TMB-8 and Quin 2 suppressed melittininduced flinching behaviors. These results indicate that calcium ion in the spinal dorsal horn neurons and peripheral nerves plays an important role in the production and maintenance of mechanical allodynia and spontaneous pain by melittin.

Lymph Node Metastasis after Spontaneous Regression of Non-Small Cell Lung Cancer

  • Jeong, Jae Hwa;Choi, Pil Jo;Yi, Jung Hoon;Jeong, Sang Seok;Lee, Ki Nam
    • Journal of Chest Surgery
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    • v.52 no.2
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    • pp.119-123
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    • 2019
  • Spontaneous regression of lung cancer is a very rare and poorly understood phenomenon. A 64-year-old man presented to Dong-A University Hospital with a shrunken nodule in the right lower lobe. Although the nodule showed a high likelihood of malignancy on needle aspiration biopsy, the patient refused surgery. The nodule spontaneously regressed completely in the next 17 months. However, the subcarinal lymph node was found to be enlarged 16 months after complete regression was observed. We pathologically confirmed metastasis of squamous cell carcinoma and performed neoadjuvant chemotherapy, surgery, and adjuvant chemoradiation. Regardless of tumor size reduction, it is preferable to perform surgery aggressively in cases of operable lung cancer.

The Effect of Fibrin Glue as a Prevention Against Spontaneous Pneumothorax (Fibrin Glue가 자연기흉의 재발에 미치는 영향)

  • 이석열
    • Journal of Chest Surgery
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    • v.24 no.6
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    • pp.570-578
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    • 1991
  • The spontaneous pneumothorax is the sudden collapse of the lung usually by air leakage from the ruptured sub-pleural bleb and has high recurrence rate. For prevention against recurrence, many drugs such as tetracycline, talcum powder, quinacrine, etc. have been used but the effects are not satisfactory. We reduced the recurrence rate successfully by the fibrin glue instillation through the chest tube. From the January 1989 to September 1990, we have managed 65 patients of spontaneous pneumothorax with closed thoracostomy and fibrin glue[fibrinogen 1gm/50ml with approtinin 3, 000kIU /ml, thrombin 5, 000IU /ml in 3% each 10ml] instillation through the chest tube. And we compared the results with those of 106 patients of spontaneous pneumothorax who were managed only by the closed thoracostomy from January 1985 to December 1988. Only the patients who visited our hospital with recurrence were considered as the recurred cases but the others were considered as not recurred. And the removal of chest tubes usually done 3 days after cessation of air leakage or 2 days after fibrin glue instillation Statistical analysis was done by X2-test. The results were as followings: 1. The recurrence rate of fibrin glue instillation group was lower than that of non-instillation group[1st attack: 15.1% versus 27.6% p<0, 05, the 2nd attack: 33.3% versus 73.7% p<0.01, the total 18.5% versus 35.8% p<0.01]. 2. The mean duration of chest tube drainage in the fibrin glue instillation group was shorter than non-instillation group[4.24$\pm$1.36 days versus 4.48$\pm$1.73 days p<0.05]. 3. The mean duration of hospitalization was shorter in the instillation group [8.12$\pm$3.5 days versus 10.8$\pm$3.8 days p<0.05] The complications were transient mild fever, chest pain, pleural effusion in 46 cases of 65 patients, but those didn`t make any problem. We concluded that the fibrin glue is effective in the reduction of recurrence rate, obliteration of air leakage and duration of hospitalization.

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The Study for the Single-based Propellant Shelf Life extension (단기추진제 저장수명 연장을 위한 방안 연구)

  • Bong, Ha-Gyu;Yoon, Keun-Sig
    • Journal of Applied Reliability
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    • v.5 no.3
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    • pp.357-371
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    • 2005
  • Nitrogen oxide gases which were produced by spontaneous reaction of nitrocellulose (NC) in the single base propellant accelerate the decomposition of propellant, and result in the reduction of shelf life, The amount of nitrogen oxide was reduced by the addition of $0.3wt\%$ CaCO3 to conventional stabilizer(DPA) which extended the shelf life of the single base propellant as much as twice compared with commercial propellant.

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Retro-odontoid Synovial Cyst with Os Odontoideum and Atlantoaxial Instability

  • Kim, Sang-Woo;Chang, Chul-Hoon;Kim, Seong-Ho
    • Journal of Korean Neurosurgical Society
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    • v.39 no.3
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    • pp.221-223
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    • 2006
  • We report the case of a patient with a retro-odontoid synovial cyst, coupled with os odontoideum and atlantoaxial instability. We observed the regression of the cyst after C1-2 transarticular screw fixation and posterior wiring without direct surgical excision of the cyst on the follow-up MR images, which were obtained two and three months postoperatively. The myelopathic symptoms and signs of this patient were resolved by degrees.

Studies on Neuropharmacological Effects of Clitoria ternatea Linn. Root Extract in Rats and Mice

  • Boominathan, R.;Devi, B.Parimaladevi;Mandal, Subhash.C
    • Natural Product Sciences
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    • v.9 no.4
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    • pp.260-263
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    • 2003
  • Ethanol extract of the root of Clitoria ternatea Linn (CTEE) was evaluated for different neuropharmacological actions, such as general behaviour, exploratory behaviour, muscle relaxant activity and phenobarbitone induced sleeping time, in rats and mice. The extract was found to cause reduction in spontaneous activity, decrease in exploratory behavioural pattern by the head dip and Y- maze test, reduction in the muscle relaxant by rotarod, $30^{\circ}C$ inclined screen and traction tests. In addition CTEE significantly potentiated the phenobarbitone-induced sleeping time. Preliminary tests indicate that the ethanol extract of Clitoria ternatea Linn. At the doses of 100 and 150 mg/kg showed significant neuropharmacological activity.

TREATMENT OF DENTIGEROUS CYST USING MARSUPIALIZATION : A CASE REPORT (조대술을 이용한 함치성 낭종의 치료증례)

  • Kang, In-Sung;Yang, Kyu-Ho
    • Journal of the korean academy of Pediatric Dentistry
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    • v.25 no.3
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    • pp.613-618
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    • 1998
  • A dentigerous cyst is an epithelium-lined sac that surrounds the crown of an impacted, embedded, or unerupted tooth. Many surgical procedures have been described for the elimination of dentigerous cyst, but they can be devided into two basic group: enucleation and marsupialization. Marsupialization is a conservative technique which allows the reduction or elimination of a cystic lesion by making it an accessory compartment to the oral cavity and it is the best way to conserve a tooth affected by dentigerous cyst and to permit its eruption, especially in young patient. After using marsupialization to treat dentigerous cyst associated with the crown of unerupted premolar in young patient, the results were as follows: 1. Reduction of bony expansion and rapid bone regeneration without infection and recurrence were observed. 2. Normally spontaneous eruption of involved teeth were permitted, as well as loss of affected tooth was avoided. 3. Follow-up examinations revealed no complication and recurrence.

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A Spontaneous Growth of a Diaphorase Enzyme Layer over a Gold Electrode for the Catalytic Reduction of $NAD^+$

  • Kim, So Hyeong;Yun, Se Ok;Gang, Chan
    • Bulletin of the Korean Chemical Society
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    • v.22 no.11
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    • pp.1192-1196
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    • 2001
  • A diaphorase enzyme electrode for the catalytic reduction of NAD+ , the oxidized form of nicotinamide adenine dinucleotide, has been prepared. The enzyme layer grew spontaneously over an aminoethanethiol self assembled monolayer on a go ld plate electrode. The growth was accomplished by simply dipping the electrode covered by the aminoethanethiol monolayer into a solution containing both glutaraldehyde and diaphorase. We suggested that the glutaraldehyde as a cross-linking reagent was attached to the amino groups of the aminoethanethiol monolayer and the diaphorase enzyme molecules were bound to free aldehyde groups of the glutaraldehyde. Further attachments of the enzyme molecules over the bound enzyme molecules continued with the bridging of the glutaraldehyde. In frequency measurements with a quartz crystal microbalance, the frequency decrease was much more than it was for that of the enzyme monolayer formation, and an enzyme layer thicker than a monolayer was formed. The modified electrode was employed to reduce NAD+ , using diffusional methyl viologen as an electron transfer mediator. The NAD+ was electrocatalytically reduced, and the catalytic current was almost equivalent to that with the multilayered electrode of ten enzyme layers.

Ameliorating Effects of HPM-1 on Scopolamine-induced Memory Impairments in Mice (몰약 당귀 오미자 혼합제제 HPM-1의 Scopolamine에 의해 유도된 기억력 감퇴에 대한 개선 효과)

  • Ahn, Jeewoon;Kim, Dae-Sung;Cho, Hyoung-Kwon;Kim, Youn-Chul;Kim, Sung Yeon;Oh, Hyuncheol;Seo, Jungwon
    • Korean Journal of Pharmacognosy
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    • v.46 no.3
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    • pp.243-249
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    • 2015
  • Myrrh, Angelicae Radix, and Schisandrae Fructus have been used to treat diverse diseases including neurological disorder in the traditional Korean medicine. In the present study, we investigated the ameliorating effects of HPM-1, a combined extract of Myrrh, Angelicae Radix and Schisandrae Fructus, on scopolamine-induced memory impairments in mice. First, we assessed HPM-1, HPM-2 and HPM-3, in which Myrrh was extracted with water, 30% ethanol, and 30% ethanol/3% vinegar, respectively. The oral administration of HPM-1, HPM-2, or HPM-3 significantly reversed scopolamine-induced reduction of spontaneous alternation in the Y-maze task. In the passive avoidance task, HPM-1 or HPM-3 restored the decreased latency time of the retention trial by scopolamine treatment, but in terms of efficacy, HPM-1 showed more beneficial effects than HPM-3. In addition, HPM-1 administration reversed scopolamine-induced reduction of spontaneous alternation in the Y-maze task and scopolamine-decreased latency time in the passive avoidance in a dose-dependent manner. These results suggest that HPM-1 has the therapeutic potential in memory impairments.