• Title/Summary/Keyword: Occlusion pressure

Search Result 130, Processing Time 0.025 seconds

A Study on Cerebral Ischemia-Reperfusion Injury: Involvement of Platelet-Activating Factor (뇌의 허혈-재관류손상에 대한 연구: 혈소판활성인자의 관련)

  • Lee, Won-Suk;Rhim, Byung-Yong;Hong, Ki-Whan
    • The Korean Journal of Pharmacology
    • /
    • v.29 no.1
    • /
    • pp.1-8
    • /
    • 1993
  • To elucidate involvement of platelet-activating factor (PAF) in cerebral ischemia-reperfusion injury, male Sprague-Dawley rats and albino mice of either sex were subjected to a 10-min bilateral carotid artery occlusion and 6-hr recirculation. The McGraw stroke index in mice was markedly inhibited by PAF antagonists, BN 52021 and CV 6209 (1 mg/kg, i.p., each) When they were administered 10 min before bilateral carotid artery occlusion or 1 hr after reperfusion. The increases in brain water content were significantly attenuated by treatment with BN 52021 or CV 6209 in both animals. BN 52021 exhibited a significant improvement in the postischemic blood pressure change in association with a beneficial effect on the delayed dilatation of pial arterioles after 10 min of ischemia. Thus it is suggested that PAF plays an important role as an endogenous mediator in development of cerebral ischemia-reperfusion injury, and further, specific antagonists to PAF will be able to prevent or reverse the pathological sequelae of cerebral ischemia.

  • PDF

Assessment of Cerebral Collateral Circulation Using $^{99m}Tc$-Hexamethyleneamine Oxime (HMPAO) SPECT During Internal Carotid Artery Balloon Test Occlusion (내경동맥 풍선 시험 결찰술(BTO)시 $^{99m}Tc$-HMPAO 뇌 SPECT를 이용한 대뇌 측부 순환의 평가)

  • Ryu, Young-Hoon;Yun, Mi-Jin;Chung, Tae-Sub;Lee, Jong-Doo;Park, Chang-Yun
    • The Korean Journal of Nuclear Medicine
    • /
    • v.29 no.1
    • /
    • pp.22-30
    • /
    • 1995
  • To predict preoperatively the safety of permanent occlusion of an internal carotid artery with $^{99m}Tc$-HMPAO brain single photon emission computed tomography(SPECT) from an objective point of view, Twenty-four patients underwent balloon test occlusion (BTO) of the internal carotid arteries because of neck and skull base tumors. The authors assessed the uptake of both middle cerebral artery territories before and during BTO with $^{99m}Tc$-HMPAO brain SPECT using semiquantitative analysis method and compared the results with other factors(neurologic examination, arterial stump pressure and electroenceph-alogram). Nineteen patients had not experienced neurological deteriorating or any problem during BTO. Their comparative uptakes of the middle cerebral artery territories were 95 to 101% of the pre-BTO state. The remaining five patients showed severe neurologic symptoms such as transient hemiplegia and unconsciousness. Their comparative uptake of the middle cerebral artery territories were 77 to 85% of the pre-BTO state, and were well matched with other factors. $^{99m}Tc$-HMPAO brain SPECT before and during BTO seems to be a simple and objective method for prediction of permanent neurologic deficits when the comparative uptake of middle cerebral artery territories during BTO is lower than 85% of that before BTO.

  • PDF

The Effect of Dodamtang(DDT) on Brain damage and Hypertension (도담탕(導痰湯)이 뇌손상(腦損傷) 및 고혈압(高血壓)에 미치는 영향(影響))

  • Lim, Seong-Min;An, Joung-Jo;Choi, Young;Kim, Yong-Jin;Yoo, Ho-Ryoung;Park, Yang-Chun;Seol, In-Chan;Hwang, Chi-Won;Cho, Hyun-Kyung
    • The Journal of Internal Korean Medicine
    • /
    • v.22 no.4
    • /
    • pp.503-512
    • /
    • 2001
  • Objective : This study was carried out to investigate the effects of DDT on the brain damage and hypertension. Methods : We observed the effect of Dodamtang(DDT) extract on KCN-induced coma, focal brain ischemia by MCA occlusion, cytotoxicity and protection of PC12 cells and B103 cells induced by amyloid ${\beta}$ protein(25-35). To prove the effect of DDT as a blood pressure depressant, we measured aldosterone, renin activity, catecholamine, sodium and NO density using the seperated blood plasma. Results : DDT showed a protective effect on cytotoxicity of PC12 cells and B103 cells induced by amyloid ${\beta}$ protein(25-35) in a dose dependent manner and proved the significant abridgement of brain ischemic area and edema induced by MCA occlusion, a critical decrease of neurologic deficitic grade in the fore-limbs. DDT didn't reduce the duration of KCN(1.87mg/kg iv.)-induced coma and prolonged the survival rate in the case of KCN(3.0mg/kg iv.)-induced coma by the ratio of 20%. While DDT increased the value of NO in SHR, it significantly decreased the blood pressure of SHR and the value of aldosterone& epinephrine in SHR. Conclusions : These results suggested that DDT might be usefully applied for treatment of hypertension, cerebral infarction, and brain damage.

  • PDF

Flexual strength of resins for provisional fixed prostheses (임시 고정성 보철물 제작용 레진의 굽힘강도)

  • Choi, Myoung-Ah;Ahn, Seung-Geun;Cho, Kuk-Hyeon
    • Journal of Dental Rehabilitation and Applied Science
    • /
    • v.16 no.3
    • /
    • pp.221-227
    • /
    • 2000
  • Provisional fixed partial dentures(FPDs) are an important part of many prosthodontic treatment procedures. These provisional fixed prostheses must fulfill biologic, mechanical, and esthetic requirements to be considered successful. Consideration of all these factors and requirements are important because provisional resin restorations may be worn over a long period to assess the results of periodontal and endodontics therapies, and also during the restorative phase of implant reconstructive procedures. This in vitro study examined flexual strength of four resins commonly used for fixed provisional prostheses. The effects of polymerization conditions were also evaluated. The four resins tested were : Caulk Temporary bridge resin(L.D. Caulk Co. Dentsply International Millford), Jet(Lang Dental Mfg. Co. Chicago. ILL. U.S.A), Alike (Coe Laboratories. Inc. Chicago. ILL. U.S.A) and Tokuso Curefast (Coe Laboratories. Inc. Chicago. ILL. U.S.A) The test specimens were 65mm long, 14mm wide, and 3.5mm thickness. 10 specimens of four resins were cured for 15 minutes at atmospheric pressure and 10 specimens of four resins were cured at an additional pressure of approximately 20 psi. A total of 80 specimens were prepared. The flexual strength was determined by three-point bending test. Data were analysed with the Paired samples T-test and Tukey student-range test Within the limitations imposed in this study, the following conclusions can be drawn : 1. Under the condition of bench curing, Caulk Temporary bridge resin showed the highest flexual strength. In decreasing order, the flexual strength of the other materials was as follows : Jet, Tokuso Curefast, Alike, and Caulk Temporary bridge resin demonstrated significantly higher strength than other resins. 2. Under the condition of pressure curing, Jet showed the highest flexual strength. In decreasing order, the flexual strength of the other materials was as follows : Caulk Temporary bridge resin, Tokuso Curefast, and Alike. There were all statistically significant differences among four resins 3. There was a statistically significant difference between bench- and pressure-cured specimens in all four materials.

  • PDF

Complete denture rehabilitation of edentulous patient using mandibular suction denture: a clinical report (완전 무치악 환자에서 하악 흡착 의치를 통한 총의치 수복 증례)

  • Lim, Seo-Ryeon;Seo, Yoon-Hee;Kim, Hyun-Young;Song, Young-Gyun;Lee, Joon-Seok
    • The Journal of Korean Academy of Prosthodontics
    • /
    • v.52 no.4
    • /
    • pp.346-351
    • /
    • 2014
  • Suction dentures enhance retention and support by forming negative pressure temporarily at the internal surface of denture base at times of swallowing and chewing because the areas surrounding the denture flanges are sealed by mobile mucosa. In this case, an 81-year-old male visited for new dentures. Considering the high expectations for retention and masticatory efficiency of dentures, fabricating complete dentures with suction dentures was planned. Preliminary impression was taken without applying pressure on retromolar pad area and diagnostic cast was fabricated. Afterwards, individual tray was made and final impression was taken, at the same time, gothic arch tracing was done to acquire centric relation and vertical dimension. Then, anatomic teeth were placed on maxilla and non-anatomic teeth were placed on mandible forming lingualized occlusion. Consequently, restoring a complete edentulous patient with complete dentures using mandibular suction denture resulted in recovering satisfying retention and function.

Clinical Study of Multiple Cardiac Valve Replacement : A Report of 63 Cases (중복심장판막이식의 임상적 고찰 63예 보고)

  • Suh, Kyung-Pill;Yang, Gi-Min
    • Journal of Chest Surgery
    • /
    • v.13 no.4
    • /
    • pp.405-413
    • /
    • 1980
  • A total of 63 patients [42 males and 21 females] underwent multiple valve replacement with artificial valves between January 1975 and August 1980 at Seoul National University Hospital. There were 38 patients with aortic and mitral valve replacement, 22 with mitral and tricuspid, and 3 with aortic, mitral and tricuspid valve replacement. The valve lesions varied from trivial to severe and most aortic and mitral valves had mixed stenosis and insufficiency, while tricuspid valves had only insufficiency. The patients were severely symptomatic in majority of the cases, and belonged to the Classes III and IV [III:45, IV:16] of the NYHA functional criteria. Hemodynamic studies were performed on all the patients. The mean pulmonary wedge pressure was remarkably increased to 19.8 mmHg in aortic and mitral valve lesions and 18.0 mmHg in mitral and tricuspid valve lesions. The mean pulmonary arterial pressure was also increased, while the cardiac index was reduced. In 1977, the average perfusion time was 245.5 minutes for aortic and mitral valve replacement and 181.6 minutes for mitral and tricuspid valve replacement. It has progressively declined to 169.2 minutes for aortic and mitral valve replacement and 123 minutes for mitral and tricuspid valve replacement in 1980. The average period of aortic occlusion also declined after the use of cardioplegic solution. Twenty deaths occurred among the 63 patients operated upon, an overall mortality rate of 30.8%. The operative mortality has declined with successive year from a level of 66.7% before 1977 to 21.1% in 1980. Fourteen patients suffered from a list of postoperative complications, which eventually resolved with adequate treatment. All the survivors were enjoying the levels of daily life activities greater than those existing before the operation.

  • PDF

Effects of Angelicae Gigantis and Cynanchum wilfordii Hemsley Extract on the Changes of Cerebral Flow (당귀와 백수오 추출물이 뇌혈류 변화에 미치는 영향)

  • Jeong, Hyun Woo;Yang, Dong Hyuk;Song, Min Sun;Jeong, Jong Gil;Lee, Sang Young;Choi, Chan-Hun
    • Journal of Physiology & Pathology in Korean Medicine
    • /
    • v.27 no.4
    • /
    • pp.446-452
    • /
    • 2013
  • This study was designed to investigate the effects of Angelicae Gigantis and Cynanchum wilfordii Hemsley extract (AAC) on the changes of regional cerebral blood flow (rCBF) and mean arterial blood pressure (MABP) in normal rats, and in the rats with cerebral ischemia induced by middle cerebral artery occlusion, and further to determine the mechanisms. The results were as follows. AAC significantly increased rCBF but significantly decreased MABP in a dose-dependent manner in normal rats. The increase of AAC-induced rCBF was significantly inhibited by pretreatment with methylene blue (0.01 mg/kg, i.p.), an inhibitor of guanylate cyclase, and AAC-induced MABP was decreased by pretreatment with methylene blue. In cerebral ischemics, rCBF was stably improved by AAC (10 mg/kg, i.p.) during the period of cerebral reperfusion, which was contrasted with the findings of rapid and marked increase in the control group. These results suggest that AAC can increase rCBF in the normal state, as well as improve the stability of rCBF in cerebral ischemic state.

Experimental Effects of Sibjeondaebo-tang and Gamy-Sibjeondaebo-tang on Cerebral Hemodynamics in Cerebral Ischemia Rats (십전대보탕(十全大補湯)과 가미십전대보탕(加味十全大補湯)이 뇌허혈 흰쥐의 뇌혈류역학에 미치는 실험적 영향)

  • Lee, Sang Young;Jeong, Hyun Woo
    • Journal of Physiology & Pathology in Korean Medicine
    • /
    • v.27 no.2
    • /
    • pp.173-182
    • /
    • 2013
  • This Study was designed to investigate the effects of Sibjeondaebo-tang (SDT) and Gamy-Sibjeondaebo-tang (GST, Sibjeondaebo-tang adding Cervi Pantotrichum Cornu) on the improvement in regional cerebral blood flow (rCBF) and mean arterial blood pressure (MABP) in normal rats, and in the rats with cerebral ischemia induced by middle cerebral artery occlusion, and further to determine the mechanisms. And, It was to investigate the effects of the SDT and GST with the change of histologic examination through the BDNF in the hippocampus CA1. In changes of cerebral hemodynamics, SDT and GST significantly increased rCBF in a dose-dependent manner but decreased MABP in normal rats. In mechanism of cerebral hemodynamics, Increase of GST-induced rCBF was significantly inhibited by pretreatment with methylene blue (0.01 mg/kg, i.p.), an inhibitor of guanylate cyclase, and Decrease of GST-induced MABP was significantly increased by pretreatment with methylene. These results suggested that the action of GST was mediated by guantlate cyclase pathway. In cerebral ischemics, the rCBF was stably improved by SDT (10 mg/kg, i.p.) significantly and stably increased by GST (10 mg/kg, i.p.) during the period of cerebral reperfusion, which contrast with the findings of rapid and marked increase in Control group. These results suggested that GST had anti-ischemic action in cerebral ischemic state. In histological examination through TTC stain, Sample A group and Sample B group decreased discoloration in the cortical part at $28^{th}$ day after MCAO induction. In immunohistochemistric response of BDNF, Sample A group and Sample B group increased respondent effect at $28^{th}$ day after MCAO induction. These results suggest that GST can Increase rCBF in normal state, as well as improve the stability of rCBF in cerebral ischemic state. Furthermore, methylene blue inhibitor study suggested the mechanism of blood flow enhancement by GST may be mediated by guanylate cyclase pathway.

Effects of Yanggyuksanhwa-Tang(凉膈散火湯) on Cerebral Blood Flow and Ischemic Brain Damage in Rats (양격산화탕(凉膈散火湯)이 뇌혈류(腦血流) 및 뇌허혈(腦虛血) 손상(損傷)에 미치는 영향)

  • Shin, Min-Gyu;Song, Il-Byung;Son, Sang-Kon
    • Journal of Sasang Constitutional Medicine
    • /
    • v.13 no.2
    • /
    • pp.165-176
    • /
    • 2001
  • This study demonstrates the effects of Yanggyuksanhwa-Tang, Sasang constitutional herb prescription reported its clinical effect on the stroke of the So-yang In(少陽人), on the cerebral blood flow changes induced by nitro L-arginine methyl ester (L-NAME) treatment and ischemic brain damage induced by the middle cerebral artery occlusion (MCAO) in the rats. The changes of the arterial blood pressure, cerebral blood flow, and the diameter of the pial artery were measured in rats treated with L-NAME. And the changes of the infarct size, volume, and plasma tumor necrosis factor alpha ($TNF-{\alpha}$) levels were measured in the rats that the middle cerebral artery has been occluded by the intraluminal suture thread method. Yanggyuksanhwa-Tang was administered by the i.v. injection on the L-NAME treated rats, by the i.o. administration on the MCAO rats. The results is 1. The changes of the arterial blood pressure was not different statistically between in the L-NAME treated control group and in the Yanggyuksanhwa-Tang administered group. 2. Increase in the cerebral blood flow induced by L-NAME treatment was attenuated in the Yanggyuksanhwa-Tang administered group significantly (P<0.05) as compared with the L-NAME treated control group. 3. Decrease in the diameter of the pial artery induced by L-NAME treatment was attenuated about 18% in the Yanggyuksanhwa-Tang administered group as compared with the L-NAME treated control group. 4. Ischemic damaged infarct areas were decreased significantly (P<0.05) in the interaural 12mm, 10mm, and 6mm brain sections of the Yanggyuksanhwa-Tang administered group as compared the MCA occluded control group. 5. Total ischemic infarct volume was decreased significantly (P<0.05) in the Yanggyuksanhwa-Tang administered group as compared the MCA occluded control group. 6. Plasma $TNF-{\alpha}$ levels were decreased significantly (P<0.01) in the Yanggyuksanhwa-Tang administered group as compared the MCA occluded control group.

  • PDF

THE EFFECTS OF THE OCCLUSAL TRAUMA ON THE PERIODONTAL TISSUES (교합외상(咬合外傷)이 치주조직(齒周組織)에 미치는 영향(影響)에 관(關)한 실험적(實驗的) 연구(硏究))

  • Chang, Wan-Shik
    • The Journal of Korean Academy of Prosthodontics
    • /
    • v.16 no.1
    • /
    • pp.7-11
    • /
    • 1978
  • The author attempted to observe the histological changes of the periodontal structures induced by trauma from occlusion. Eighteen healthy rabbits were devided into two groups; control and experimental group. Three rabbits were kept as control group, while metal crowns were seated on unilateral lower molar teeth of fifteen rabbits were kept as experimental group. And the interocc1usal distance of the incisal edge was kept 1.5mm from begining to the end of the experimental period. Rabbits of each group consisting with three rabbits were killed at the intervals of three days, one week, two weeks, four weeks, eight weeks. The antagonistic teeth of maxilla including periodontal teeth were excised and decalcified for histologic preparation. The results obtained were as follows. 1. Destructions and ulcer formation of the sulcular epithelium and gingival epithelium occurred and persisted from the beginning of the experiment to the four weeks after experiment. The epithelal attachment were proliferated apically. 2. The pressure site were observed at the apical protion, where they showed compression of the periodontal ligament, thrombosis and congestion of blood vessels and hemorrhages. 3. At the pressure site, there appeared osteoclasts and bone resorption from the first week of experiment and it became more prominent at the second week with the extend into the marrow spaces adjacent to the periodontal membrane. 4. The phenomenon of bone apposition and resorption occurred at the fourth week of experiment. The reverse line of bone trabecular were more prominent. And the reactions were ceased at the eighth week of experiment.

  • PDF