BACKGROUND: Herpes simplex virus thymidine kinase (HSVtk) phosphorylates the prodrug ganciclovir to a nucleoside analog that inhibits DNA synthesis, causing cell death. Neighbouring nontransfected cells may be affected through a 'bystander effect', thereby amplifying the antiproliferative actions. This study was carried out to determine whether retrovirus-mediated HSVtk gene therapy could reduce intimal hyperplasia and prevent stenosis following balloon injury of the rat carotid artery. METHODS: A replication-defective recombinant retroviral vector containing HSVtk cDNA (LtkSN) was constructed. Cultured primary rat smooth muscle cells (SMCs) infected with this vector (SMC/LtkSN) were transplanted to the balloon injured rat right carotid artery. One week after transplantation, HSVtk gene therapy group was administered a 2-week treatment of ganciclovir (30 mg/kg/d). Three weeks after balloon injury and SMC/LtkSN transplantation, carotid arteriography was performed and carotid arteries were perfusion-fixed for histologic examination. RESULTS: Carotid arteriographic evaluation comparing with the uninjured left carotid artery showed that the mean luminal diameter of HSVtk gene therapy group (n=5, 85+/-3%) was significantly larger than that of balloon injury only group (n=5, 65+/-5%). The neointimal mass of HSVtk gene therapy group was less than that of balloon injury only group. SMC/LtkSN transplantation without ganciclovir treatment group (n=3) showed asymmetric intimal proliferation probably because of gravitational pooling of seeding. There were inflammatory cell infiltrations at the gravity dependent portion of HSVtk gene therapy group. CONCLUSION: Retrovirus-mediated HSVtk gene therapy following balloon injury of the rat carotid artery reduced neointimal expansion and arteriographic stenosis.
Angiography ; Animals ; Carotid Arteries* ; Carotid Artery Injuries* ; Cell Death ; Constriction, Pathologic* ; DNA ; DNA, Complementary ; Ganciclovir ; Genetic Therapy* ; Gravitation ; Herpes Simplex* ; Hyperplasia ; Myocytes, Smooth Muscle ; Phenobarbital ; Phosphotransferases* ; Rats* ; Simplexvirus* ; Thymidine Kinase ; Zidovudine

Primary carcinoma of the bile duct is uncommon but not rare and its prognosis is poor even though long-termsurvival had been reported. The authors presented 62 cases of bile duct cancer, which were confirmed at YUMC fromJan. 1971 to Dec. 1981. The results were as follows; 1. The most prevalent age group was 6th decade and a male-tofemale ratio was 1.9:1. 2. Jaundice was the most common clinical manifestations(84%), and followed by right
Bile Duct Neoplasms ; Bile Ducts ; Bile ; Cholangiopancreatography, Endoscopic Retrograde ; Common Bile Duct ; Diagnosis ; Dilatation ; Hepatomegaly ; Humans ; Jaundice ; Prognosis ; Ultrasonography

BACKGROUND: Pacing-induced atrial electrical remodeling (AER) is characterized by shortening of atrial effective refractory period (A-ERP) and its altered rate adaptation. In paroxysmal atrial fibrillation (AF), periods of AF occur with interveneing normal sinus rhythm (NSR) when atria recover from the preceding AER. Previous episodes of AF may precondition the atrial myocardium and cause different time course of AER in subsequent episodes of AF. But the influence of the preceding AER on the subsequent AER has not been described. METHODS: Four mongrel dogs were anesthetized with enflurane. After thoracotomy, silicon band with 3 pairs of electrodes was sutured to the lateral wall of the left atrium. Atrial pacing was performed after 2 wks of recovery and autonomic blockade. Pacing protocol consisted of rapid atrial pacing (RAP) at 500 bpm (for 60 min) and recovery in NSR (for 60 min) which was repeated three times. A-ERP was measured every 10 min. The same pacing protocol was repeated after pretreatment with verapamil (0.1 mg/kg/hr). RESULTS: 1) With 60 min of RAP, A-ERP decreased significantly (126+/-6 ms vs. 105+/-7 ms, p<0.005). 2) After cessation of pacing, A-ERP returned to 98% of baseline value in 15 minutes. Recovery from AER occurred faster than AER (78 vs 21 ms/h). 3) After pretreatment with verapamil, RAP decreased A-ERP from 127+/-5 ms to 116+/-5 ms. AER, the reduction in A-ERP, was significantly attenuated by pretreatment with verapamil (deltaERp=17+/-7 vs. 9+/-0.2 %, p<0.05). 4) When RAPs were repeated, AER showed a tendency of acceleration, but it was not statistically significant (deltaERp=22 ms, 24 ms, 28 ms at the end of 60 min pacing for the 1st, 2nd, 3rd pacing). CONCLUSION: RAP induced AER in conscious dog atria and it was reduced by pretreatment with calcium channel blocking agent, verapamil. Upon repeated atrial stimulations, AER did not accelerate or decelerate when the atria recovered from the preceding AER.
Acceleration ; Animals ; Atrial Fibrillation ; Atrial Remodeling* ; Calcium ; Calcium Channels ; Dogs* ; Electrodes ; Enflurane ; Heart Atria ; Myocardium ; Silicones ; Thoracotomy ; Verapamil

BACKGROUND: Several kinds of stents have shown their safety and efficacy to treat acute or subacute closure after balloon angioplasty as well as to reduce restenosis rate. However, one of the limitations of stents is difficult to deploy especially in tortuos vessels, lesions at a bend, and distal to previously deployed stents. The Micro stent II, which was one of the most recently developed stents, ia a rapid-exchage balloon expandable stainless steel stent with a zigzag design connected with a continuous single weld in each 3mm segments. It scores over excellent trackability and optimum radio-opacity. Therefore, it is easy to operate and feasible in tortuous, distal lesions and variety of lesion lengths. We report our experiences with Micro-II stent implanatation in the first 76 patients at Tonsei cardiovascular center to assess its safety and efficacy in patients with complex coronary anatomy and clinical results in the first months. METHODS: Between January 1996 and July 1996, eighty-six Micro-II stent were implanted in the coronary arteries of 76 patients(male 65.8%, age 59+/-10 year). Forty-five patients had unstable angina, the others had stable angina(17pts), acute myocardial infarction(14pts). RESULTS: 1) Indication of stenting was de novo 51(59.3%), suboptimal result 25(29.1%), restenosis 1(1.2%) and 9(10.4%) of lesions were stented in bail out situation. 2) Single stent were implanted in 76(88.4%)lesions, overlapping stent in 10(11.6%)lesions. Among overlapping stents, the second stent with Micro-II stent and with another kind of stent were 4.6%, 7.0%, respectively. 3) Procedure related complication including a subacute closure was occurred in 1(1.2%) patient who had distal dissection and 45% residual stenosis. In 12(14%) lesions, preistent dissection has been noticed after stent impantation. 4) Angiographic success(defined as a residual stenosis of <30% without major dissection) was achieved in 82 of 86 attempts(95.3%). The procedual success rate(defined as a residual stenosis of <30% without occurrence of major clinical events within 4 weeks after procesure) was 96.1%(73/76 patients). Angiographic success and procedural success rate in calcified lesion were 100% and 100%, respectively. Angiographic success and procedural success rate in more than 45` angulated lesion were 97% and 100%, respectively. 5) The mean minimal luminal diameter of the target lesions was increased from 0.42+/-0.40mm before stent implantation to 2.93+/-0.50mm(p<0.001). The percentage of diameter stenosis was reduced from 86.49+/-13.04% to 1.40+/-7.11%(p<0.001) after stent implantation. CONCLUSION: Coronary stenting with AVE Micro-II stent can be safety performed and is particularly beneficial in tortuous and calcified arteries. There was a high tendency for peristent dissection which need to special consideration to avoid. Follow-up data is needed to assess mid and term patency. Coronary artery disease . AVE Micro-II stent . Immediate results.
Angina, Unstable ; Angioplasty, Balloon ; Arteries ; Constriction, Pathologic ; Coronary Artery Disease ; Coronary Vessels ; Follow-Up Studies ; Humans ; Phenobarbital ; Stainless Steel ; Stents*

Subcutaneous emphysema is one of the rare complication of tracheal intubation and it's mechanism has been known as airleakage to subcutaneous tissue from the perforated site of larynx, trachea and esophagus by the trauma of laryngoscopic blade, stylet and endotracheal tube. We experienced a case of subcutaneous emphysema during unexpected difficult endotracheal intubation. At the initial laparoscopic examination, the patient's laryngeal view was grade IV of Cormack and Lehane's calssification. After several trial of the intubation, cervical subcutaneous emphysema developed by the trauma of laryngoscopic blade, stylet and endotracheal tube, even though failed to confirm the perforated site at postanesthesia one day.
Esophagus ; Intubation ; Intubation, Intratracheal* ; Larynx ; Subcutaneous Emphysema* ; Subcutaneous Tissue ; Trachea

Amniotic fluid embolism (AFE) is a rare but devasting obstetric emergency. We experienced a case of AFE during dilatation and curettage (D & C) in a 15 2/7 weeks pregnant woman, age 30, who was diagnosed as having a missed abortion. Sudden rapid hypoxemia, low SpO2, hypotension, low PETCO2, high CVP, and tachycardia, right axis deviation and right bundle branch block in 12 leads ECG were developed during D &C under general anesthesia, and signs of disseminated intravascular coagulation (DIC) followed after the operation, which are consistent with the findings of AFE. Even though there was no definite pathologic and radiologic confirmation of AFE, laboratory findings showed 100 times higher level of alpha-fetoprotein in her central venous blood than same weeks of missed abortion woman's blood. Though it is rare, the anesthesiologist should always suspect the possibility of AFE, when the patient shows an unexplained collapse, cyanosis, low PETCO2, high CVP, low SpO2, ECG change and DIC during any kind of obstetric procedure.
Abortion, Missed ; alpha-Fetoproteins ; Amniotic Fluid* ; Anesthesia, General ; Anoxia ; Axis, Cervical Vertebra ; Bundle-Branch Block ; Cyanosis ; Dacarbazine ; Dilatation and Curettage* ; Dilatation* ; Disseminated Intravascular Coagulation ; Electrocardiography ; Embolism, Amniotic Fluid* ; Emergencies ; Female ; Humans ; Hypotension ; Pregnancy ; Pregnancy Trimester, Second* ; Pregnant Women ; Tachycardia

OBJECTIVE: The purpose of this study was to compare the static (SFF) and kinetic frictional forces (KFF) of a computer-aided design and computer-aided manufacturing lingual bracket (CAD/CAM-LB) with those of conventional LB (Con-LB) and Con-LB with narrow bracket width (Con-LB-NBW) under 3 tooth displacement conditions. METHODS: The samples were divided into 9 groups according to combinations of 3 LB types (CAD/CAM-LB [Incognito], Con-LB [7th Generation, 7G], and Con-LB-NBW [STb]) with 3 displacement conditions (no displacement [control], maxillary right lateral incisor with 1-mm palatal displacement [MXLI-PD], and maxillary right canine with 1-mm gingival displacement [MXC-GD]; n = 6/group). While drawing a 0.016-inch copper or super-elastic nickel-titanium archwire with 0.5 mm/min for 5 minutes in a chamber maintained at 36.5℃, SFF and KFF were measured. The Kruskal-Wallis method with Bonferroni correction was performed. RESULTS: The Incognito group demonstrated the highest SFF, followed by the 7G and STb groups ([STb-control, STb-MXLI-PD, Stb-MXC-GD] < [7G-MXC-GD, 7G-MXLI-PD, 7G-control] < [Incognito-MXLI-PD, Incognito-control, Incognito-MXC-GD]; p < 0.001). However, there were no significant differences in SFF among the 3 displacement conditions within each bracket group. Within each displacement condition, the Incognito group demonstrated the highest KFF, followed by the 7G and STb groups ([STb-control, STb-MXLI-PD] < Stb-MXC-GD < 7G-MXLI-PD < [7G-control, 7G-MXC-GD] < [7G-MXC-GD, Incognito-MXLI-PD, Incognito-control] < [Incognito-control, Incognito-MXC-GD]; p < 0.001). MXC-GD exhibited higher KFFs than MXLI-PD in the same bracket group. CONCLUSIONS The slot design and ligation method of the CAD/CAM-LB system should be modified to reduce SFF and KFF during the leveling/alignment stage.

A 66-year-old male was admitted for increasing azotemia. He was diagnosed with chronic antibody- mediated rejection and had received a livingdonor renal transplant from his 32-year-old son prior to his admission. The peritubular capillaries of his kidney were diffusely positive on C4d immunostaining. It is known that there is an agreement between C4d staining and serological and histopathological data during rejection that is thought to have a humoral component. The role of alloantibodies in chronic renal allograft deterioration and the corresponding morphologic changes have been increasingly recognized during the recent years. However the treatment guidelines for chronic antibody-mediated rejection have not yet been established. Intravenous immunoglobulin (IVIG) has been shown to decrease the titers of anti-HLA antibodies in highly sensitized patients awaiting transplant. There are also numerous proposed mechanisms regarding how IVIG exerts its immunomodulatory action. As we have experienced chronic antibody-mediated rejection and how IVIG treatment improves renal function, we recognize that IVIG has the potential to be used for treating certain subgroups of chronic allograft nephropathy patients with positive C4d staining and anti-HLA antibodies.
Adult ; Aged ; Antibodies ; Azotemia ; Capillaries ; Complement C4b ; HLA Antigens ; Humans ; Immunoglobulins ; Immunoglobulins, Intravenous ; Isoantibodies ; Kidney ; Male ; Peptide Fragments ; Rejection (Psychology) ; Transplantation, Homologous ; Transplants

No abstract available.
Melanoma ; Nevus ; Nevus, Pigmented ; Warts

BACKGROUND AND OBJECTIVES: Mechanisms of restenosis following successful coronary angioplasty (PTCA) are knownasvascularsmoothmuscle cells(VSMCs)proliferationandmigration, elastic recoil or vascular wall remodeling. Paclitaxel whose effect on the stabilization of microtubles leads to cell death is highly lipophilic, permitting easy pass through cell membrane, and has a long-term antiproliferative effect. This study was performed to evaluate effect of paclitaxel on VSMCs proliferation and whether locally delivered paclitaxel can prevent stenosis and neointimal formation in rat carotid artery injury model. MATERIALS AND METHODS: Cultured VSMCs were exposed to sequential concentrations of paclitaxel in vitro, and proliferation inhibition was analyzed with 3H-thymidine incorporation. Paclitaxel of a suitable concentration was applied to the endothelium-denuded carotid artery of Fisher 344 inbred rats for 20 minutes. Angiogram and morphometric analysis of carotid artery was performed after 2 weeks. RESULTS: 3H-thymidine incorporation in cultured VSMCs was decreased dose-dependently from the concentration of 0.1 micromol/L (2,454+/-149cpm/ microgram protein) to 100 micromol/L (1,323+/-69cpm/ microgram protein) of paclitaxel by single and 20-minute exposure in the presence of platelet-derived growth factor (p<0.005). In the absence of platelet-derived growth factor, the decrement of 3H-thymidine incorporation was evident above the concentration of 5 micromol/L of paclitaxel. To evaluate in vivo effect, paclitaxel (0.1 or 1 micromol/L) was administered into the endothelium-denuded carotid artery by balloon injury and incubated for 20 minutes. Percent stenoses (32.2+/-9.8%) of paclitaxel-treated group was less than those (46.3+/-7.5%) of control group on histologic analysis (p<0.01). Paclitaxel-treated group also had wider lumen on carotid angiogram and less neointimal thickening than control on histologic examination (p<0.005). CONCLUSION: Proliferation of VSMCs was effectively inhibited and neointimal formation and luminal stenosis was prevented in rat carotid artery injury model by single, brief and local delivery of low-dose paclitaxel. This strategy could be applied to clinical settings for the prevention of restenosis after PTCA.
Angioplasty ; Animals ; Carotid Arteries* ; Carotid Artery Injuries ; Cell Death ; Cell Membrane ; Constriction, Pathologic ; Neointima ; Paclitaxel* ; Phenobarbital ; Platelet-Derived Growth Factor ; Rats*