The roles of sympathicus, sensory neuropeptides (SNP), cyclooxygenase metabolites (COX-M), lipoxygenase metabolites (LOX-M), endothelium derived relaxing factor (EDRF), reactive oxygen (ROS) and potassium channels (PC) in the hypoxic pulmonary vasoconstriction (HPV) and hypoxic cerebral vasodilation (HCVD) were investigated in intact rats, rabbits and dogs. The results showed that during hypoxia, the excitation of sympathicus caused a constriction of both pulmonary and cerebral vessels, while SNP, EDRF and the opening of voltage sensitive PC caused the dilation of both of them; LOX-M mediated HPV and HCVD, COX-M might serve as their modulators; the blockade of ATP sensitive PC induced by hypoxia mediated HPV, but had no effect on HCVD; the reduction of O2- in the lung might potentiate HPV, however, O2- remained unchanged in brain during hypoxia. It is suggested that the alterations of LOX-M, ROS and the ATP sensitive PC are the factors accounting for the difference in the response of pulmonary and cerebral vessels to hypoxia.
Two expressing plasmids have been constructed and used to express two bifurictional-domain recombinant polypeptides of human fibronectin (FN) inE. coli. One was CH50 (Pro1239-Ser1515 of FN linked with Ala1690-Thr1960 of FN through Met) and the other was CH56 (Pro1239-Thr1960 of FN). Both of two polypeptides were capable of binding heparin and were purified by heparin-agarose affinity chromatography. The purified products were capable of binding cells. The production of CH50 and CH56 polypeptides provided a fundamental basis for further study of the anti-metastatic function of recombinant fibronectin polypeptides.
The flow cytometric immunoassay was used to study the correlation between the H-ras oncogene product p21 and the DNA ploidy in 30de novo cases of acute myelogenous leukemia (AML). The results showed that 17 cases were negative for p21 expression and 13 positive for p21. The patients with positive p21 had higher percentage of bone marrow and peripheral blasts and lower peripheral leukocyte count. The expression of p21 had no influence on the therapeutic effect. Before treatment, DNA diploidy occurred in 18 cases including 13 p21 negative ones, and DNA aneuploidy was revealed in 12 cases including 8 p21 positive ones. Patients with positive p21 or having, aneuploidy in complete remission were at risk for early relapse. Our results suggest that p21 may be involved in the process of leukemogenesis and progression in AML.
The serum free medium conditioned by cultured rabbit aortic smooth muscle cells was partially purified using ultrafiltration and heparin affinity chromatography. Incorporation of [3H]-thymidine (3H-TdR) into cell DNA was used to measure the mitogenic activity of the fractions from chromatography for NIH 3T3 fibroblasts. The molecular weight and the iso-electric point of these fractions were determined by NaDodSO4-polyacrylamide gel electrophoresis (SDS-PAGE) and iso-electric focusing, respectively. The results showed that the protein eluted in 1. 0–1. 6 mol/L NaCl from the heparin-Sepharose was mitogenic for 3T3 cells, and this protein had a molecular weight of 22. 8–26. 7 ku and an iso-electric point of about 4. 6. The fact that the above-mentioned biochemical properties differed from that of PDGF, IGF and FGF suggests that this mitogenic protein may be a separate growth factor.
The regulation of cellular differentiation by progesterone in fetal rat calvarial osteoblasts was investigated. Our results showed that cells cultured in the presence of progesterone had a 7% increase in the alkaline phosphatase activity when compared to untreated cells. The concentration of osteocalcin in the conditioned medium from progesterone treated osteoblasts was 28 % higher than that of untreated controls. In addition, administration of progesterone significantly enhanced the number and area of bone nodules. In conclusion, progesterone stimulates the differentiation of fetal rat calvarial osteoblastic cellsin vitro
The effect of domestically-manufactured excimer laser with adjunctive balloon angioplasty in achieving revascularization and reduction of residual stenosis was assessed. 20 femoral arteries with thrombosis and occlusion from 12 dogs were subject to angiography. At first excimer laser angioplasty was done followed by balloon angioplasty. The diameter and residual stenosis of revascularized vessel were measured. The result showed that 17 out of 20 vessels (85 %) were revascularized. The diameter of revascularized vessel by excimer laser were 1. 22 ±0. 14 mm, while residual stenoses were 54 %±5 %. After adjunctive balloon angioplasty the diameter and residual stenoses were 2. 04±0.16 mm and 20 %±7 % respectively (P< 0. 05 andP< 0. 01). Complication in form of vasoperforation occurred in 3/20 vessels(15%). It is concluded that Chinamanufactured excimer laser angioplasty is effective when used for revascularization. While the reduction of narrowing and residual stenoses was enhanced after adjunction of balloon angioplasty. This method can be employed in treating peripheral occlusive disease effectively and safely.
In order to investigate the value of perioperative echocardiography in percutaneous balloon mitral valvuloplasty (PBMV), two-dimensional echocardiography (2-DE), Doppler echocardiography and color Doppler flow imaging (CDFI) were employed prior to PBMV in 52 patients and during or after PBMV in 15 patients. The results showed that TTE and TEE were helpful in the selection of candidates for 2-DE transseptal and balloon dilation procedures. Continuous monitoring of 2-DE, Doppler echocardiography and CDFI during PBMV could make this procedure safer and more effective, reduce X-ray exposure and avoid complications. Echocardiography was useful in fluoroscopy and could be used for evaluation of the effects of operation.
This paper reported 3 cases of ascending aortic dissecting aneurysm treated by modified Cabrol’s operation. An 8 mm Gore-Tex connected with coronary arteries was employed to prevent high tension, intimal tearing and bleeding of anastomosis. Unremoved aneurysmal wall used as a sac for enclosing conduit graft could minimize the bleeding and oozing so that leaked blood can be drained to right atrium via a bypass.
By determining the plasma levels of C3, C4, factor B and polymorphonuclear neutrophils (PMNs) of the patients who received CPB, the path of complement activation and changes of PMNs were studied. The results suggest that complement system was activated through alternative pathway during CPB and was activated through classic pathway after CPB. The anaphylatoxin, the products of complement activation may be responsible for the polymorphonuclear neutrocytopenia.
The effects of tetrandine (TD) on endogenous cardiac noradrenaline (NA) release evoked by electrical stimulation were investigated in perfused guinea pig hearts. The overflow of cardiac NA and its intraneuronal metabolite 3,4-dihydroxyphenylethyleneglycol-(DOPEG) were determined by high pressure liquid chromatography (HPLC) In the presence of TD, the release of NA evoked by either nerve ganglion-stimulation or cardiac field-stimulation was significantly reduced (P< 0. 01). The overflow of DOPEG was markedly enhanced (P< 0. 01). TD inhibited cardiac endogenous NA release resulting from activation of the sympathetic nerve terminals within the myocardium, and increased the release of DOPEG, indicating that TD could result in a loss of NA from storage vesicles or activate monoamine oxidase in axoplasma, which could be detected by markedly increased DOPEG release. These effects of TD may be associated with its property of calcium antagonist.
By using computer imaging analysis system combined with light microscopy, the glomeruli lesions on biopsy specimens sections were quantitatively analysed. The patholoical changes of mesangial proliferative glomerulonephritis (MsPGN) in children were quantitatively evaluated and the correlation between the mesangial matrix area (MA) and some clinical data were also analysed. The results indicated that the levels of various glomerular parameters in MsPGN group were higher than those of normal controls. No correlation was found between MA and 24 h urinary protein excretion, but a negative correlation was revealed between MA and estimated GFR. MA was also correlated with the duration of MsPGN recovery. It was suggested that the quantitative analysis of glomerular parameters by computer is a reproducible methods. The parameter of MA may be used for evaluation of the renal function, determination of the duration of therapy and evaluation of prognosis of MsPGN in children.
From May, 1990 to Sept., 1993 106 cases of primary liver cancer were treated by temporary or permanent hepatic arterial embolization with Bletilla striata powders (permanent, 56 cases) or gelfoam powders (temporary, 50 cases) under controlled technical conditions. In term of degree of tumor necrosis, revascularization of tumor, and long-term effect, the results of Bletilla striata group were better as compared with those of gelfoam group. The 1, 2 and 3 year survival rates were 44. 9%, 33. 6% and 33. 6% in Beltilla striata group while the rates were 48. 9%, 31.1% and 16. 0% in gelfoam group, suggesting that Bletilla striata is superior to gelfoam as an embolizing agent for hepatic carcinoma.
Effect of domestically-made levonorgestrel-releasing intrauterine device (LNG, release rate: 6 μg/day) on the endocrine system and menstruation in mondeys was investigated. The results showed that the Estradiol (E2) and progesterone (P) levels were significantly decreased 2 ovulatory cycles after insertion of the devices as compared with those before insertion in 3 monkeys (P> 0. 001), suggesting an evident ovulation-suppressing effect. In 1 monkey, the E2 and P levels were the same before and after insertion, and expulsion of device was found in the monkey later. The plasma LNG concentration in 3 animals was 493. 69–454. 60 pg/ml and plasma LNG was not detected in 1 monkey. The hormone level returned to normal level after removal of the devices.
The effects of steroid on diaphragmatic contractility and endurance were examined in 24 New Zealand rabbits. Diaphragmatic contractility was determined by measuring gastric pressure (Pga) with the lower thorax and the abdomen of the animal being fixed with a rigid cast. Endurance procedure was done by continuous 15 Hz stimulation of the bilateral phrenic nerves, and diaphragmatic endurance was expressed as the time from the initiation of the endurance procedure to the moment when transdiaphragmatic pressure 15 Hz (Pdi-15 Hz) decreased to 25% of Pdimax-15 Hz. Our data suggested that intravenous administration of dexamethasone 2. 5 mg daily for 7 days did not affect the diaphragmatic contractility significantly, but could cause a significant decrease in diaphragmatic endurance. When delivered intravenously at the dose of 2. 0 mg daily for 14 days, dexamethasone induced a significant decrease both in diaphragmatic contractility and endurance. The recovery of the diaphragmatic strength from fatigue, however, was not influenced by dexamethasone in either circumstance. The influence of dexamethasone on diaphragmatic contractility and endurance may have important clinical implications.
Anesthesia was induced with intravenous thiopental, fentanyl, and succinylcholine, and maintained with isoflurane, N2O-O2 and atracurium after denitrogenation in 20 adult patients. Inspired and end-tidal concentrations of O2, N2O, CO2, isoflurane and oxygen saturation of pulse oximeter (SpO2) were monitored. After intubation, N2O (750 ml/min) and O2(250 ml/min) were administrated. When inspired N2O concentration (FiN2O) reached 60 % the closed anesthesia was initiated by adjusting fresh gas flow rate in order to meet the oxygen demand of the patients. The N2O/O2 ratio was constantly kept at 0. 7. The results revealed that during wash-in period, FiN2O increased, on average, to 30 % at 3. 83 min, 40 % at 6. 22 min, 50 % at 14. 13 min respectively. After 30 min of closed anesthesia, FiN2O decreased to 49. 4 %. It was 46. 8 % at 60 min. Thereafter it increased smoothly to 51. 9 % at 180 min. No hypoxia and hypercapnia occurred. Compared with commonly used high flow N2O-N2 inhalation, the technique of low flow wash-in and closed circuit maintenance with N2O-O2 may be less expensive and feasible and causes less pollution.