1995年 · 第108卷第09期

A 150 bp epidermal growth factor (EGF) cDNA fragment and a 1024 bp epidermal growth factor receptor (EGFR) cDNA fragment were inserted into 5.05 kb pBabe-puro retroviral vectors between BamH I and EcoR I sites in 3'-5' and/or 5'-3' orientation. The vectors were ligated with EGF and EGFR fragments by T-4 Ligase. The recombinant retroviral vectors were then packaged with packaging cell line PA317 through calcium phosphate mediated transfection. The viral supernatant of transfected PA317 cell lines were used to infect the human pancreatic carcinoma cell line PC-7. The resultant transformant cell lines: PC-7/AS-EGF, PC-7/S-EGFR, PC-7/AS-EGFR and PC-7/pBabe were tested for their endogenous EGF and EGFR mRNA expressions, cell growth rate, 3H-TdR incorporation rate, soft agar colony formation and tumorigenicity in nude mice. The results showed that there were noticeable inhibitions of cell growth, 3H-TdR incorporation rate, soft agar colony formation and tumorigenicity in nude mice in PC-7/AS-EGF and PC-7/AS-EGFR transformant cell lines. The endogenous EGF mRNA expression was blocked in PC-7/AS-EGF cell line and the endogenous EGFR mRNA was significantly down-regulated in PC-7/AS-EGFR cell line.

The effects of the extracts of 20 Chinese medicinal herbs and an antiviral drug foscarnet on duck hepatitis B virus (DHBV) endogenous DNA polymerase (DNAp) activity were compared. The extracts of P. urinaria showed a dose-dependent inhibition on DHBV DNAp. And those of other herbs showed little inhibition effect. Primary duck hepatocyte (PDH) cultures were used for evaluating effects of the extract of P. urinaria, foscarnet and acyclovir (ACV) on DHBV, and all the drugs or the extracts showed inhibition of DHBV DNA replication. Furthermore, in vivo trials were carried out. Peking ducks infected with LJ-76 strain of DHBV were treated with the extract of P. urinaria or ACV and compared with placebo treated control ducks. The treatment results in the loss or reduction of circulating viral DHBV DNA and DHBsAg.

The effect of partial pressure of isoflurane on its solubility in blood of different haematocrit was determined at different isoflurane partial pressures, using a syringe--flask method and gas chromatography with blood from one donor. The solubility of isoflurane decreased with increasing blood haematocrit (39.5%, 51.9% and 61.9%) and isoflurane partial pressure from 1 MAC to 4 MAC. The solubility in 50% and 60% haematocrit blood at 2, 3 and 4 MAC was significantly different from the solubility in normal blood at 1 MAC (P<0.05). We conclude that the solution of isoflurane in blood (especially in high haematocrit blood) does not obey Henry's law.

Quantitative analysis of P53 protein expression was performed on paraffin-embedded tissues from 55 smooth muscle tumors of the gastrointestinal tract, using immunofluorescence and flow cytometry. No positive expression was found in normal smooth muscle tissues of the gastrointestinal tract. Over-expression of P53 gene was found in a significantly higher proportion in leiomyosarcomas (90%) and potentially malignant smooth muscle tumors (75%) as compared to leiomyomas (14%) (P<0.005). The quantitation of P53 expression was found to be progressively enhanced in the sequence from leiomyoma through potentially malignant smooth muscle tumor to leiomyosarcoma (P<0.005). It was markedly over-expressed when the mitotic counts ranged from one to more than one per 10 high power fields (P<0.005) or the mild cytologic atypia was found (P<0.005). The five-year survival rate was significantly higher in patients with low-expression of P53 than in those with over-expression of P53 (P<0.005). It was suggested that P53 over-expression might be associated with the transformation of leiomyoma into leiomyosarcoma and could be used as an objective parameter in distinguishing the malignant from the benign and predicting the prognosis of patients with smooth muscle tumors of the gastrointestinal tract.

Electrophysiology study and radiofrequency catheter ablation (RFCA) were performed in 26 patients with refractory sustained ventricular tachycardia (VT). After induction of VT, 12-lead electrocardiogram (ECG) was recorded and QRS morphology and axis of induced VT were studied to identify the origin of VT. The precise site of VT origin were localized by pace mapping and activation mapping carefully. RF energy was delivered through a big-tip deflectable electrode catheter when the earliest site of endocardial activation and a high-frequency and low-amplitude potential of Purkinje fiber, preceding surface QRS by more than 25 ms, were identified and/or a pace map was obtained showing identical QRS complexes in at least 11 of 12 ECG leads. VTs were ablated successfully in 24 of 26 patients (success rate was 92%). For successful ablation, it is essential that the pace map QRS morphology in 12 leads should be identical with that in spontaneous or induced VT as far as possible in performing pace mapping. Pace mapping is safe, simple and has no unfavourable effect hemodynamics although it takes longer time. Activation mapping takes shorter time and has a high success rate. QRS configuration in spontaneous VT can help to localize the site of VT origin. Deliberate mapping at the site suggested to bo the origin of VT by surface ECG can shorten the duration of mapping and increase the success rate of RFCA. RFCA of VT in patients without structural heart disease is effective, safe, and has a high success rate, so it may be considered as an early therapy for these patients.

The effects of perindopril and metoprolol on left ventricular hypertrophy (LVH) and function were studied in 47 essential hypertensive patients with LVH. Previous antihypertensive drugs were discontinued for at least 2 weeks, after which patients were randomly divided into 2 groups. 25 subjects were treated with perindopril 4 to 8 mg once daily in the morning (Group A) and 22 subjects with metoprolol 25 to 62.5 mg twice daily (Group B). The subjects were evaluated before and after 4 and 8 weeks of treatment by use of echocardiography. Before treatment LV mass indexes (LVMI) of two groups were respectively 143.2±21.3 g/m2 and 140.6±23.7 g/m2 (P>0.05). In Group A, reduction of LVMI occurred after 4 weeks of treatment, and more pronounced after 8 weeks (from 143.2±21.3 g/m2 to 126.6±15.3 g/m2, P<0.001), whereas reduction of LVMI occurred only after 8 weeks in Group B (from 140.6±23.7 g/m2 to 133.4±13.2 g/m2, P<0.001). In addition, there was a significant (P<0.05) difference in LVMI between the two groups after 8 weeks. LV systolic function remained unchanged, whereas E/A increased significantly (P<0.001) in two groups after 8 weeks. In conclusion, antihypertensive treatment with perindopril and metoprolol induced a significant regression of LVH associated with improvement in LV diastolic performance. Perindopril, compared with metoprolol, was more effective in reversing LVH.

A biochemical some enzymes of glycolysis and a partial reversed tricarboxylic acid cycle together with hydrolytic enzymes in the cyst wall of Echinococcus granulosus was carried out. Lactate dehydrogenase (LDH), pyruvate kinase (PK), phosphoenolpyruvate carboxykinase (PEPCK), and adenosine triphosphatase (ATPase) showed their high level of activity, suggesting that the proliferation of E. granulosus cyst wall is an energy-dependent process and the major pathways for glucose metabolism is glycolysis. Treatment of E. granulosus-infected mice with mebendazole and albendazole resulted in marked inhibition of PK, PEPCK and ATPase of E. granulosus cyst wall, whereas praziquantel had no effect, indicating that PK, PEPCK, and ATPase might be chemotherapeutic targets and the differences in the inhibitory effects might account for the efficacy of the three antihydatid drugs.

From 1975 through 1990, 199 patients with limited small cell lung cancer (LSCLC) were subjected to multimodality treatment including surgical resection combined with chemotherapy or chemoradiotherapy in our department. The median postoperative survival time of the 199 patients was 39 months, and the 5-year survival rate was 26%, which was decreased with increase of tumor-stage. In comparison of the survival time of patients in Stage Ⅰ and those in Stage Ⅲa, there was a significant difference (P<0.01). There were no significant differences in survival rate of 3 and 5 years between the patients receiving chemotherapy prior to or after surgical resection. The improvement in survival was documented by surgical resection combined with chemotherapy or chemoradiotherapy for LSCLC. The effect of multimodality treatment is correlated with tumor P-TNM staging, the involvement of lymph node, especially that of the mediastinal lymph node, is a negative factor influencing the prognosis. Surgical resection is an initial management, followed by chemotherapy or chemoradiotherapy may be indicated in LSCLC patients of Stage Ⅰ, Stage Ⅱ and some Stage Ⅲa as the cancer can be resected completely.

The clinical radiologic manifestations of 8 patients with osteopetrosis (4 males and 4 females) are analyzed. Six of the cases are benign. The pathologic basis for the radiologic manifestations is discussed, and a classification is suggested. "Broom-like" metaphyses, metaphyses containing three or four dense layers of bone, and ossification of soft tissues around joints were found and differential diagnosis was made.

Polyclonal antibodies directed against human recombinant basic fibroblast growth factor (bFGF) were used in immunohistochemical studies to localize this growth factor in normal and wounded rat skeletal muscles. bFGF immunoreactivity was found mainly in the extracellular matrix, primarily in the endomysium, including the heparin-containing basal lamina and also in the capillary basal membrane of both normal and wounded muscles, however the signal intensity was much stronger in normal muscles. After 4-hour ischemia, about 40% of skeletal muscle fibers lost their bFGF immunoreactivity. Muscles which experienced 4-hour ischemia and 24 reperfusion had only a weaker bFGF immunoreactivity. The pathological results supported the concept of destroyed cell connection and fiber necrosis in ischemia and reperfused muscles. The mechanisms involved in this reduced concentration of bFGF in wounded muscles included oxygen radical activation, inflammatory response and reduced secretion of endogenous bFGF. These results were only partially compatible with the established mitogenic role of this protein and suggested that a reduction of endogenous FGF may partly contribute to a delay in wound healing.

Schistosomiasis due to Schistosoma japonicum was once a disastrous parasitic disease in China. Before thr founding of the People's Republic of China and in the earlier phase of the national control programme in the 1950s, prevalence, morbidity and mortality rates due to S. japonicum infection were considerably high.

Vitiligo is a systemic disease which affects the mucocutaneous melanocytes, and pigmentary cells in other parts of the body. Its cause is still unclear. The medicinal and surgical therapies for vitiligo at present in China are introduced below.

During the development of human fetus, all organs consisting of various types of cells are in rapid growth. The significance of these cells and the chemical components involved, especially those of special functions in medical treatment of certain refractory diseases, have been noticed gradually.

Post-stroke Antihypertensive Treatment Study (PATS) was a randomized, double-blind and placebo-controlled trial, which aimed at determining whether antihypertensive treatment could reduce the risk of fatal and nonfatal stroke incidence in patients with a history of stroke or transient ischemic attack (TIA). 5,665 patients were randomized by a sealed envelope system. Systolic blood pressure (SBP) ranged from 80 to 280 mm Hg and diastolic (DBP) from 50 to 150 mmHg. The average SBP was 154 mmHg and average DBP 93 mmHg. The mean age was 60 years. Among the patients, women accounted for 28%. In 71% the latest stroke was ischemic. Average follow-up approximated to 2 years. The three-year average SBP was 149 mmHg for the placebo group and 144 mmHg for the indapamide treatment group, and the three-year DBP was 89 mmHg and 87 mmHg respectively. The three-year first incidence of fatal and nonfatal stroke was 12.3 per 100 patients placebo treatment and 9.4 per 100 with indapamide. The relative risk by proportional hazards regression analysis was 0.71 (P=0.0009). For deaths from all causes, the relative risk was 0.91. (P>0.05). The findings of this trial indicate that in patients with a history of stroke or TIA, blood pressure reduction of 5/2 mmHg with 2.5 mg indapamide reduced the first incidence of fatal and nonfatal stroke by 29%, with three-year absolute benefit of 29 events per 1000 participants.