Based on the gate-related receptor hypothesis, an analysis of kinetics of AN-132, a new antiarrhythmic agent, blockade of cardiac sodium channels and the gate-related receptor which is bound by the drug was performed by computer simulation. Model-predicted apparent rates of onset of AN-132 (30 μmol/L) blocking were 0.051, 0.038, and 0.034 AF⁻¹ at stimulation frequencies of 1.0, 2.0 and 3.0 Hz, respectively. The time constant of recovery from block by AN-132 at resting potential -90 mV was 39.5 s. These findings are in agreement with those experimental data documented. The analysis of gate-related receptor shows that AN-132 binds the inactivation gate-related receptor, and the binding and unbinding are modulated by the inactivation process.

A newly designed dual fiber optical sensor is reported. It can sense both oxygen and carbon dioxide in gas phase with one sensing layer made of immobilizing fluorescent dyes Pyrene Butyric Acid (PBA) and Hydroxy Pyrene Trisulphonate (HPTS) in the same matrix. Its resolution is 0.1% for carbon dioxide and 0.5% for oxygen in clinical detecting range.

The direct effect of hypoxia and the effect of hypoxic endothelial cells conditioned medium on cultured pulmonary arterial smooth muscle cells in vitro were studied with phase contrast microscopy,³H-thymidine labelled technique and flow cytometric measurements. The results showed that direct hypoxia inhibited proliferation of pulmonary arterial smooth muscle cells, retained pulmonary arterial smooth muscle cells in the Go/G₁ phase and decreased³H-thymidine incorporation into pulmonary arterial smooth muscle cells and that hypoxic endothelial cells conditioned medium stimulated proliferation of pulmonary arterial smooth muscle cells, promoted pulmonary arterial smooth muscle cells from G₀/G₁ phase to S phase and increased³H-thymidine incorporation into pulmonary arterial smooth muscle cells. It was reasonable to believe that hypoxia might enable pulmonary arterial endothelial cells to secrete some growth factors which could stimulate proliferation of pulmonary arterial smooth muscle cells, thereby playing an important role in structural remodeling of the pulmonary arteries and in the development of hypoxic pulmonary hypertension.

Alteration of cytosolic free calcium ([Ca²⁺₁]) in hypoxia was studied with fluorescent probe, Fura-2 in cultured porcine pulmonary arterial endothelial cells. It was found that hypoxia caused by bubbling the cell suspension with 100% N₂ increased [Ca²⁺₂] in endothelial cells by 90±20% (n=8,P<0.05), but didn’t affect that in a Ca²⁺-free buffer, La³⁺ (2×10⁻⁵ mol/L) inhibited the hypoxia-induced increment in [Ca²⁺]₁, whereas verapamil (10⁻⁸ mol/L) didn’t. These findings suggest that hypoxia could induce Ca²⁺ influx in pulmonary arterial endochelial cells, which might play an important role in vascular response to hypoxia.

With the use of duplex Doppler ultrasound and color Doppler flow imaging(CDFI), the characteristics of blood supply in neoplasma were studied in 51 cases of 60 liver tumors, and compared with the results of surgery, pathological examination and hepatic anerial angiography. The result showed that: 1. Doppler blood flow signals could be detected in all hepatic carcinomas, and in 10 cases of 18 hemangiomas, significant difference was observed (P<0.001); 2. Doppler blood flow spectra showed pulsatile pattern in 41 of 42 hepatic carcinomas, and in 6 of 10 hemangiomas (P<0.01); and 3. the peak flow velocity was obviously lower in hemangioma group than in hepatic carcinoma group (20.34±23.93 vs 64.74±30.18 cm,P<0.001). The characteristics of CDFI show that hemangiomas and hepatocellular carcinomas are different. It can, therefore, be concluded that the blood supply of hepatic carcinomas mainly comes from hepatic arterial system, and is of value in duplex Doppler ultrasound and CDFI.

It is difficult for conventional transthoracic echocardiography (TTE), by which precise and accurate images of interatrial septum (IAS) can not be acquired, to diagnose patent foramen ovale (PFO) clearly. To evaluate the diagnostic value of biplanar transesophageal echocardiography (TEE) for PFO, TTE and biplanar TEE were performed simultaneously in 270 patients. It was found that in 7 patients patent foramen ovale was detected only through longitudinal planes of biplanar TEE. IAS, which consists of primitive septum and membrane of fossa ovalis, can be directly visualized by two-dimensional images of TEE; in patients with PFO, a dull color flow, which shunts from the right atria to the left atria through the gap between primitive septum and fossa ovalis, can be detected by color Doppler flow images. Furthermore, some right-to-left shunting microbubbles through the valve of patent fossa ovalis can be discovered by cardiac acoustic contrast echocardiography. In conclusion, biplanar TEE combined with color Doppler image and cardiac acoustic contrast facilitates a definite diagnosis of patent foramen ovale as the excellent anatomic images of IAS can be obtained from multiple views under this kind of performance.

Dengue virus(DV) samples which harvested after having been either propagated in C₆/36 cells or passaged by murine intracerebral inoculation were investigated by Western bloting. Two different denaturing methods with the same solution were selected before electrophoresis, one at 60 °C for 20 min; the other at 100°C for 5 min. After the samples were heated at 60°C for 20 min, 3 bands of sizes 46 ku, 70 ku and 98 ku were positively recognized by rabbit immunized sera. The peptide of 98 ku was DV group specific; While that of 46 ku could also react with the sera against both heterologous DV serotype and Japanese B encephalitis virus (JEV), After the samples were heated at 100 °C for 5 min, 3 peptides in size of 20 ku, 46 ku and 57 ku were recognized by the rabbit sera against both homologous and heterologous DV serotypes, while the peptide of 57 ku could also be recognized by anti-JEV serum. There was no significant difference in the results of Western blot between the DV antigens harvested from cellular culture and those from intra-cerebral inoculation.

Monoclonal antibodies (McAb) to Ki-67, BrdU and OKT₉ were used in APAAP technique for determining the proliferative cells of 46 myelodysplastic syndromes (MDS) with 16 serving as normal controls. According to Ki-67 positive labelling, the proliferative fractions of bone marrow cells can be divided into low (< 25%), intermediate (25%–35%), and high (> 35%) grades. The labelling positivity of Ki-67, BrdU and OKT₉ in MDS was all higher than that of the controls. Furthermore, the positive percentages of these three McAbs were significantly correlated. From the results of our experiment, an increase in proliferative fraction was related to clinical classification, prognosis, and therapy of MDS. On the other hand, the positive percentage of Ki-67 > 40% and BrdU > 30% or ratio of BrdU to Ki-67 > 80% may be considered as parameters for unfavourable prognosis.

The effect of exogenous nerve growth factor(NGF) examined on the neural repair of adult rabbit sciatic nerve was evaluated in the present study. A nerve regeneration chamber was created by suturing the proximal and distal ends of a transected sciatic nerve into a silicone chamber, A gap of 6 mm in chamber was left after removal of a 3mm piece of nerve in the distal ends and insertion of the proximal andl distal stumps into the chamber. Animals were operated on bilaterally, one side of the chamber was filled with a 1 mg/ml NGF/normal saline(NS) (experimental)and the contralateral side with NS(control). The regenerated nerves from within the silicone chamber were dissected and fixed 1 to 5 weeks following surgery for histological studies at both the light microscopic and ultrastructural levels. The NGF chamber showed a more mature regenerated nerve based on a larger diameter of the regenerated nerve trunk, a great number of axons, and thicker myelin sheaths.

Hormonal abnormality in experimental varicocele induced by partial ligation of left renal vein and the effect of thymosin (fraction 5) on the secretion of the sexual Hormone were studied in rats. Serum testosterone level was lowered after varicocele formation, but could be reversed or increased by intraperitoneal administration of thymosin 5 mg/rat twice a week for 4 weeks with concomitant increase of testicular testosterone content. Changes in FSH and LH both in serum and testis, determined with immunoassay meihod as that of testosterone, were insignificant as compared with control or thymosin treated groups.

The present study was undertaken to evaluate the improved protection of antegrade aortic root perfusion combined with intermittent coronary sinus occlusion(APCSO) for the 1-hour ischemic myocardium in the presence of left anterior descending artery occlusion. 12 dogs were divided into 2 groups: anteperfusion(AP) alone(n=6) and APCSO (n=6). The experimental results showed that APCSO provided a better cardioplegic distribution and a lower hypothermia (15.6°C versus 17.2°C) in the occluded LAD region, comrared with AP. After ischemia, cardiac index and left ventricular stroke index recovered excellently in APCSO (128% to 141% and 115% to 158% of preischemic values, respectively), and much worse in AP (69% to 82% and 53% to 73% of preischemic values, respectively). Our study has confirmed that APCSO is superior to AP in myocardial protection in the presence of coronary artery occlusion.

Cu, Zn, Mn, Se were determined in erythrocytes in 43 patients with gestational trophoblastic disease(GTD), and T cell subsets were also monitored in peripheral blood in 37 cases.The results revealed that the contents of Cu and Se in erythrocytes in patients with GTD were significantly higher than those in normal females, the contents of Zn in patients with hydatidiform mole(HM) and Mn in patients with GTD were significantly lower than those in normal females, and so were the absolutes of lymphocytes, T cell and T subsets in peripheral blood in patients with GTD, the T₄⁺/T₈⁺ ratio in patients with HM and high risk gestational trophoblastic tumor(GTT) was obviously lower than that in normal controls. The above findings led us to hold thac the alteration of crace elements(TE) in patients with GTD affects their immunologic function and is closely related to the occurrence and development of GTD.

Experimental varicocele was induced by partial ligation of the left renal vein in rats, and the effect of thymosin (fraction 5), a hormone secreted by the thymus, on the level of cyclic nucleotides was investigated. The levels of cAMP and cGMP in plasma and testicular tissue were estimated using radioimmunoassay techniques. The results showed that the level of cAMP in bilateral testicular tissues in rats with experimental varicocele decreased considerably, especially in the left testicular tissue as compared with that in the control group (P<0.05). 4 weeks after thymosin administration (0.5 mg/rat, twice a week), the level of cAMP in bilateral testicular tissues rose significantly, as compared with that in the experimental varicocele group (P<0.01). These findings indicate that there exists imbalance in the metabolism of cyclic nucleotides in rats with experimental varicocele. This suggests that the abnormal level of cyclic nucleotides is one of the causes of infertility with varicocele. Since thymosin participates in the metabolism and regulation of cyclic nucleotides, it may have a direct or an indirect effect on the growth and function of reproductive cells.

Enzyme-linked Immunosorbent Assay (ELISA) was adopted to detect the human cytomegalovirus (HCMV) specific IgG, IgM in the blood samples of 216 pregnant women and the umbilical cord blood, as well as the HCMV antigen in the urine specimens of 91 newborn infants. Emphasis was put on the occurrence of cytomegalovirus infection during pregnancy and influence on both the mother and the infant. Our experimental results showed that HCMV IgG positive rate in the maternal sera as well as in cord sera was 93.98%; HCMV IgM positive rates were 8.8% in maternal sera and 3.7% in cord sera, respectively. In maternal sera IgG-positive group, 31.6% cord sera showed also HCMV IgG positive results. In 91 urine specimens of newborn infants, HCMV-Ag positive specimens accounted for 10.98% (10 cases). The rates of abortion, congenital malformation, stillbirth, premature fetal death, and intrauterine growth retardation (IUGR) were all apparently higher in the HCMV-IgM positive pregnant group than in the HCMV-IgM negative group. The infants of HCMV-IgM positive mothers also showed lower birth weight, height, biparietal diameter, suboccipitobregmatic diameter, occipitofronatal diameter, occipito-mental diameter than the infants of HCMV-IgM negative mothers. Meanwhile, the growth and development indices of the former showed a tendency to decrease. Placenta histological examination showed thac HCMV-IgM positive group had a higher incidence of pathological changes than HCMV-IgM negative group. Altogether, there were 8 cases of cogenital infections.