Protection of Cardiomyocytes from Acute Ischemic Injury by Protein Kinase Cepsilon Expression

BACKGROUND AND OBJECTIVES: Ischemic injury is the most common and important cause of myocardial damage. Over past decades, a number of studies have identified a protective mechanism known as ischemic preconditioning, which can block or delay cell death from ischemic injury. Protein kinase C (PKC), especially theepsilonisoform has been proposed as a key factor in the signaling pathway of ischemic preconditioning. However, whether PKCepsilon expression in cardiomyocytes can offer such protection from acute ischemia has not been explored. MATERIALS AND METHODS: To demonstrate a direct effect of PKCepsilon expression, a lentiviral vector system was established. Using the lentiviral vector, PKCepsilon was introduced to neonatal rat ventricular myocytes (NRVM) cultured under ischemic conditions, and also to adult rat myocardium subject to left coronary artery ligation. RESULTS: Compared to control, PKCepsilon expression in cultured NRVM under ischemia resulted in preserved cell density and morphology, and a reduction in cell death (77.6+/-12.8% vs 58.1+/-7.2%, p<0.05). In adult rats, the infarcted area after coronary artery ligation was markedly reduced in myocardium injected with PKCepsilon vector compared to control (11.4+/-5.3% vs 20.5+/-11.3%, p<0.01). CONCLUSION: These results provide direct evidence that PKCepsilon is a central player in protection against cell death from acute ischemia.

Surgical Treatment of the Anterior Tibial Spine Fracture: Surgical Indication and Results / 대한정형외과학회잡지

The management of fractures of the intercondylar eminence of the tibia is uncomplicated when the fracture has minimal displacement(type I) or when only anterior one-third or half of the eminence is elevated(type II)(Meyers and Mckeever 1959, 1970). The treatment of complete separation(type III) has been controversial. Many authors however recommended conservative treatment even for the completely separated fracture if the fracture fragment is not rotated. Two cases of non-union of the tibial spine fracture we experienced were; one in type IIl, and the other type II. They were treated conservatively by cast immobilization. One patient had severe anterolateral rotatory.instability and had lateral meniscal tear, and the other had transverse ligament impingement at the fracture gap which interfered the reduction of the fragment and also bony union. Through the clinical experience and the two listed non-union cases, we drafted a therapeutic plan for the avulsed tibial spine fractures. The authors recommend open reduction and internal fixation of the avulsion fracture of the tibial spine in following circumstance; 1) all of the type K complete separation injuries 2) tibial spine fracture with positive Lachman test and soft end point 3) fracture with associated ligament injury. We applied the above surgical indications for 13 cases. The authors reviewed 25 cases of the anterior tibial spine fracture patients treated at the Department of Orthopaedic Surgery, Catholic Unviersity Medical College during the period from October 1982 to August 1986 and the following results were obtained. 1. The cases were classified into 3 different categories according to the Meyers and Mckeever classification; Type I(7 cases, 29%), Type II(10 cases, 40%), Type III(8 cases, 31%). 2. Associated ligament injuries on the same knee were rupture of LCL for 7 cases(28%) and MCL for 6 cases(24%). 3. Twelve out of thirteen open reduction and internal fixation cases had excellentresult in minimum 6 months follow-up period.

The Use of Long-Acting Anesthetics Through Indwelling Catheter Afer Flexor Tenolysis / 대한정형외과학회잡지

The surgical release of flexor tendons from their restricting adhesions has historically been a somewhat controversial procedure. Especially clinical efficacy of tenolysis is dependent on early active digital motion. The administration of long acting anesthetics (Bupivacaine) through indwelling catheter after tenolysis relieved pain and so achieved early active digital motion in 12 cases. The times for tenolysis following tendon repair and the followup period were 3 months and 6 months on an average. According to flexor zones classification, in 4 patients the lesion was in zone II, 5 in zone III, 1 in zone IV and 2 in zone V. The results were as follows; 1. The functional results after tenolysis showed up 7 excellent, 4 good and 1 fair. 2. The subjective results of the postoperative pain relief showed up 8 excellent and 4 good out of 12 cases.