BACKGROUND: Although hypoxic pulmonary vasoconstriction (HPC) and hypoxic coronary vasodilatation (HCD) have been recognized by many researchers, the precise mechanism remains unknown. As isolated arteries will constrict or relax in vitro in response to hypoxia, the oxygen sensor/transduction mechanism must reside in the arterial smooth muscle, the endothelium, or both. Unfortunately, much of the current evidence is conflicting, especially concerning to the dependency of HPC and HCD on the endothelium and the role of the K+ channel. Therefore, this experiment was attempted to clarify the dependency of HPC and HCD on the endothelium and the role of the K+ channel on HPC and HCD. METHODS: HPC was investigated in isolated main pulmonary arteries precontracted with norepinephrine (NE). HCD was investigated in isolated left circumflex coronary artery precontracted with prostaglandin F2 alpha. Vascular rings were suspended for isometric tension recording in an organ chamber filled with Krebs-Henseleit solution. Hypoxia was induced by gassing the chamber with 95% N2 +5% CO2, which was maintained for 15 - 25 min. RESULTS: 1)Hypoxia elicited a vasoconstriction in NE-precontracted pulmonary arteries with endothelium, but a vasodilatation in PGF 2 alpha-precontracted coronary arteries with and without endothelium. There was no difference between the amplitude of the HPC and HCD induced by two consecutive hypoxic challenges and the effect of normoxic and hyperoxic control Krebs-Henseleit solution on subsequent response to hypoxia. 2)Inhibition of NO synthesis by the treatment with Nw-nitro-L-arginine reduced HPC in pulmonary arteries, but inhibition of the cyclooxygenase pathway by treatment with indomethacin had no effect on HPC and HCD, respectively. 3)Blockades of the TEA-sensitive K+ channel abolished HPC and HCD. 4)Apamin, a small conductance Ca2+/-activated K+ (KCa) channel blocker, and iberiotoxin, a large conductance KCa channel blocker, had no effect on the HCD. 5)Glibenclamide, an ATP-sensitive K+ (KATP) channel blocker, reduced HCD. 6)Cromakalim, an K(ATP) channel opener, relaxed the coronary artery precontracted with prostaglandin F2 alpha. The degree of relaxation by cromakalim was similar to that by hypoxia and glibenclamide reduced both hypoxia- and cromakalim-induced vasodilations. 7)Verapamil, a Ca2+ entry blocker, caffeine, a Ca2+ emptying drug; and ryanodine, an inhibitor of Ca2+ release from SR, reduced HPC, respectively. CONCLUSION: HPC is dependent on the endothelium and is considered to be induced by inhibition of the mechanisms of NO-dependent vasodilation while HCD is independent of the endothelium and is considered to be induced by activation of the K(ATP) channel.
Anoxia ; Arteries ; Caffeine ; Coronary Vessels ; Cromakalim ; Dinoprost ; Endothelium ; Glyburide ; Indomethacin ; Muscle, Smooth ; Norepinephrine ; Oxygen ; Prostaglandin-Endoperoxide Synthases ; Prostaglandins F ; Pulmonary Artery ; Relaxation ; Ryanodine ; Vasoconstriction* ; Vasodilation*

No abstract available.
Korea* ; Rotavirus*

No abstract available.
Fetal Death* ; Gastroschisis*

No abstract available.
Carcinoma, Squamous Cell* ; Female ; Ovary* ; Teratoma*

No abstract available.
Congenital Hypothyroidism*

The nonstructural protein NSP4, encoded by gene 10 of rotavirus, has been shown to play a role in viral assembly and known to be an enterotoxin, causing diarrhea in mouse pups. NSP4 gene was cloned from CBNU-2 (virulent bovine rotavirus/diarrheic fecal sample) and CBNU-1 (cell-culture adapted bovine rotavirus/isolated from CBNU-2 and 75 times passaged on MA104 cells), respectively, by reverse transcriptase-polymerase chain reaction (RT-PCR) and sequenced and compared. The sequence data indicated that the NSP4 genes of bovine rotavirus (BRV) were 751 bases in length and encoded one open reading frame of 175 amino acids beginning at base 42 and terminating at base 570. Differences in nucleotide sequence between CBNU-2 and CBNU-1 were observed at 6 positions (base 274, 296, 391, 394, 396 and 579). NSP4 gene of BRV exhibited a high degree of nucleotide (90% and 94%) and amino acid sequence (91% and 94%) and amino acid sequence (91% and 97%) homology with those of SA11 and UK but a low degree of nucleotide (77% and 79%) and amino acids sequence (81% and 85%) homology with those of Wa and OSU.
Amino Acid Sequence ; Amino Acids ; Animals ; Base Sequence ; Clone Cells* ; Cloning, Organism* ; Diarrhea ; Enterotoxins ; Korea* ; Mice ; Open Reading Frames ; Rotavirus* ; Virus Assembly

No abstract available.
Amniotic Band Syndrome* ; Anencephaly* ; Infant, Newborn

We made a randomized prospective comparison of the compression hip screw and the Gamma nail for the internal fixation of 60 intertrochanteric fractures to compare perioperative details and to analyze radiographic and clinical results in elderly patients. The operation time for Gamma nail group was shorter than for CHS group and also the intraoperative blood loss was lower in the Gamma nail group. And the Gamma nail enabled earlier ambulation. We found no significant difference of the union time and the sliding length of lag screw between two groups. The decrease of neck shaft angle in the Gamma nail group was significantly smaller than the CHS group. There was no significant mechanical complication in the Gamma nail group such as a fracture of the femoral shaft or fixation failure. We obtained satisfactory results on treatment of elderly patients with intertrochanteric fracture of femur using Gamma nail. So we consider that in the treatment of intertrochanteric fractures of geriatric patients, the Gamma nail would be more efficient than the CHS.
Aged ; Femur ; Hip Fractures ; Hip ; Humans ; Neck ; Prospective Studies ; Walking

Discoid semilunar cartilage is an abnormality in which the meniscus is discoid rather than semilunar, and first reported by Young of Glasgow in 1889. 13 cases of discoid semilunar cartilages which were experienced at the Department of Orthopedic Surgery, College of medicine, Seoul National University from Jan. 1956 till Aug. 1972 are reported with review of literature. 1) The incidence was remarkable higher in the male than in the female as 11 versus 2, and higher in the age group of second decade (Average 16.4 year old). 2) Most common site was lateral meniscus, and bilateral discoid meniscus were 3 cases. 3) 3 cases out of 13 cases had complicated rupture of semilunar cartilage, and one case had cyst of the meniscus. 4) Meniscectomy were performed in all cases with successful outcome.
Female ; Humans ; Incidence ; Male ; Menisci, Tibial ; Orthopedics ; Rupture ; Seoul

No abstract available.
Calcium* ; Erythrocytes* ; Sodium* ; Spherocytes