New plasmid vector and host system for genetic engineering in Bacillus sphaericus

A new plasmid, pNQ116, was constructed in Bacillus sphaericus by cloning a promoter fragment from B. sphaericus Ts-1 into pNQ112. The plasmid (CmrKmr, 5.23 kb) contains a restriction endonuclease polylinker used for cloning foreign genes, and its cat-86 gene is expressed at high levels from the Ts-1 promoter. This plasmid vector has been transformed into B. sphaericus AS 1.270, AS 1.465, AS 1.469, and 2362, at frequencies of 10(2)-10(3) transformants per microgram of DNA, and is maintained stably under nonselective conditions in these host strains. The presence of pNQ116 in B. sphaericus 2362 does ot interfere with the mosquito larvicidal activity of the organism.

Molecular cytogenetic study of short arm aberrations in human D, G group chromosomes

Six cases of Dp+/Gp+, 10 cases of D/G translocation, 1 case of supernumerary marker chromosome, and 1 case of Yqs were studied using molecular and cytogenetic techniques. The Ag-NOR frequencies of the Dp+ and Gp+ groups were found to be higher than those of normal controls, while their satellite association frequencies were lower. Autoradiographic silver grains were not significantly distributed along the p+ part of the marker chromosome as revealed by chromosomal in situ hybridization using an rRNA probe. This result differs from our previous report. It is suggested that there might be different mechanisms for the formation of p+ on acrocentric chromosomes. D/G translocation cases were found to have lost their NOR. A study of supernumerary marker chromosomes and Yqs cases suggested that the marker chromosome and Yqs exerted no phenotypic effect. The mechanism of their formation is discussed.

[The mortality of patients with malignant tumors in eleven cities of Jiangsu Province, 1984-1986]

The present paper analysed people in eleven cities making up one sixth of Jiangsu population. In 1984-1986 the mortality of malignant neoplasm was 163.28/10(5), (Chinese standard mortality were 116.57/10(5), the world standard mortality were 177.75/10(5)) which accounts for 25.04% of the total mortality during the same time. The trends of deaths from neoplasms show that oesophageal cancer in both sexes and leukemia in male are gradually decreasing, lung cancer in male and hepatoma in female are gradually increasing. The rank correlation analysis between chinese standard mortalities of some major malignant neoplasms indicates that the stomach cancer was positive correlated with oesophageal cancer in both sexes, the oesophageal cancer in male and the stomach cancer in female were negative correlated with lung cancer, and the breast cancer was negative correlated with oesophageal cancer in female. All this suggests that there may be likely etiologic association between these malignant neoplasms.

[An experimental study on the pathophysiology of septic ventilatory depression]

Ventilatory depression and apnea are well-known early pulmonary responses of sepsis in infants, yet their underlying mechanisms are not understood. To further elucidate the pathophysiology, we induced Escherichia coli septicemia in piglets and studied the sequential changes in intrapulmonary shunt (QS/QT), physiological dead space (VD/VT), minute ventilation (VE), and blood gases for up to 6 hours of lethal sepsis. Lung lymph was also collected and extravascular lung water (EVLW) was measured. Histology confirmed that interstitial edema developed 1 hour after E. coli infusion. These data suggest that high permeability pulmonary edema and hypoxemia following early intrapulmonary shunt increase may be the causes of septic ventilatory depression.

Berberine-induced morphologic differentiation and down-regulation of c-Ki-ras2 protooncogene expression in human teratocarcinoma cells

A pluripotent human teratocarcinoma cell clone, NT2/D1, which was derived from the Tera-2 cell line, was induced to differentiate into cells with neuronal cell morphology by treatment with berberine. As early as 1 day after a 24-h treatment of cells with berberine at a non-toxic dose of 0.1 mg/ml in culture medium, the cells started to show morphologic changes, developing into terminally differentiated neuronal cells with long, inter-connecting network-like cellular structures. This process is much faster as compared with that induced by treatment with retinoic acid (RA), which took at least several days to develop. Unlike RA, berberine could not induce murine teratocarcinoma cell line, F9, to differentiate into endodermal cells. It was also found that, although the NT2/D1 cell clone exhibited amplification and enhanced mRNA expression of c-Ki-ras2 gene as did the parent cell line, a marked down-regulation of c-Ki-ras2 mRNA expression was observed. However, there was no change in actin mRNA expression even after differentiation had occurred. Thus, morphologic differentiation of teratocarcinoma cells into neuronal cells is found to be associated with down-regulation of a protooncogene which plays some definite role in oncogenesis. The mechanism by which berberine induces differentiation in these cells needs further investigation.

[Clinical pathological analysis of recurrent oral ulcer and Behçet's syndrome]

Histopathological features of 53 cases of recurrent oral ulcer (ROU) and 28 cases of Behçet's syndrome (BS) were studied. The findings of light microscopic examinations are as follows: (1) The inflammatory cell reactions in early lesions are characterized by predominant lymphocytes and monocytes which differ from those in later lesions. (2) The vascular lesions are more significant in BS than in ROU. (3) The number of mast cells in the oral lesions of BS is more than that in ROU and controls. (4) Bacteria are observed in 11 specimens stained with HE and multinucleated epithelial giant cells are found in one specimen. It is considered that the lymphomonocytes in epithelial layer may play a role in the destruction of the epithelial cells through autoimmunization.

[Long-term results of the treatment of mandibular condyle fracture]

Long-term result of conservative and surgical treatment of varying types of mandibular condyle fracture in 34 cases was investigated. The study shows that 90% cases of condyle fracture, including that complicated with dislocation and displacement, could be successfully treated with simple immobilization by intermaxillary elastic bands. The long-term result of close reduction is closely related to the interval between the trauma and the start of treatment, the earlier the beginning of the treatment, the better the result. The unfavourable immediate result in form of imperfect occlusion and excursion, etc. could be corrected by forced mandibular movement. 10 cases complicated with badly dislocation or communicated fracture were treated with condylectomy, satisfactory results were achieved in 80% of them.