[The clinical significance of flow cytometric DNA measurement of paraffin specimen in bladder tumor]

A retrospective study of flow cytometric measurements on paraffin embedded tumor specimens from 188 patients with bladder tumor was made and the results were analyzed in combination with the morphological changes of bladder tumors. It was found that the DNA ploidy pattern, degree of infiltration and the multiplicity of bladder tumor were closely related with tumor recurrence, among which the DNA ploidy pattern was most significant. In the aneuploid bladder tumors the recurrent rate and mean annual recurrent frequency were 76.7% and 1.46, and those in the diploid bladder tumors were 18.7% and 0.33 respectively. Aneuploidy was the most indicative parameter in the recurrence of bladder tumor. In addition, according to the DNA ploidy pattern and DNA index, the aneuploid tumors in our group were divided into 4 types, namely, tetraploid tumors, non-euploid tumors with DNA index less than or equal to 1.5, non-euploid tumors with DNA index greater than 1.5 and two-aneuploid tumors. The results showed that the recurrent rate of tetraploid tumor was relatively low and it became higher and higher in the following order, e.g., non-euploid tumors with DNA index less than or equal to 1.5, non-euploid tumors with DNA index greater than 1.5 and two-aneuploid tumors, indicating that there were different biological behaviors in tumors with different ploidy patterns. Finally, the relationship between DNA ploidy pattern and tumor metastasis was also discussed.

Shortest path first with emergency exits

Under heavy and dynamic traffic, the SPF routing algorithm often suffers from wild oscillation and severe congestion, and results in degradation of the network performance. In this paper, we present a new routing algorithm (SPF-EE) which attempts to eliminate the problems associated with the SPF algorithm by providing alternate paths as emergency exits. With the SPF-EE algorithm, traffic is routed along the shortest-paths under normal condition. However, in the presence of congestion and resource failures, the traffic can be dispersed temporarily to alternate paths without route re-computation. Simulation experiments show that the SPF-EE algorithm achieves grater throughput, higher responsiveness, better congestion control and fault tolerance, and substantially improves the performance of routing in a dynamic environment.

Human immunodeficiency virus infection of human bone marrow stromal fibroblasts

The human immunodeficiency virus (HIV) preferentially infects CD4 positive T cells and monocytes. Other human cell types have been reported to be infectable with HIV, including cells of mesenchymal origin. In this report, we show that both primary human bone marrow stromal fibroblasts and an immortalized human stromal fibroblast line are susceptible to HIV infection. These cells are capable of passing HIV to cells of lymphoid or myeloid lineage, and may thereby act as a reservoir of virus. This in vitro system may be a useful model for assessing the pathophysiology of hematopoietic dysfunction in AIDS patients.

Mechanical alterations in sensitized canine saphenous vein

Because it is likely that antigen sensitization is not restricted to airway smooth muscle but probably involves all tissues in the animal, we decided to test the hypothesis that saphenous vein from pollen extract-sensitized dogs is sensitized and is, in addition, mechanically altered. To this end, we studied responses to specific antigen challenge and length-tension and force-velocity relationships in sensitized (SSV) and control saphenous veins (CSV). The antigen challenge revealed that the venous smooth muscle was strongly sensitized and developed a Schultz-Dale response, the two main mediators of which were histamine and norepinephrine. Length-tension relationship studies showed that whereas there is no difference in maximum isometric tension development between SSV and CSV [93.95 +/- 7.34 and 87.86 +/- 4.00 (SE) mN/mm2, respectively], SSV exhibited a significantly greater maximum isotonic shortening capacity of 0.613 +/- 0.009 optional length (lo) vs. 0.578 +/- 0.012 lo for CSV. Unloaded shortening velocity (Vo), which reflects the cross-bridge cycling rate, was determined at different times after the onset of electrical stimulation. Maximum Vo was attained early (5 s) in the contraction; a 15% decline in Vo was observed at the plateau of the contraction (15 s). At 5 s, Vo of SSV (0.316 +/- 0.019 lo/s) was significantly higher than that of CSV (0.269 +/- 0.018 lo/s), although Vos were same at 15 (0.249 +/- 0.021 lo/s for SSV and 0.237 +/- 0.019 lo/s for CSV). The increase in shortening likely results from th e increase in the early cross-bridge cycling rate because our studies show that the bulk of shortening occurs in the first 5 s.(ABSTRACT TRUNCATED AT 250 WORDS)

[Screening of alpha-amino acid ester hydrolase producing strain and synthesis of cephalexin by Pseudomonas aeruginosa]

From ten genera and 146 bacterial strains, 22 strains producing alpha-amino acid ester hydrolase were selected. Among them, AS 1.586 and 41-2 were the best. The optimal conditions for synthesis of cephalexin by pseudomonas aeruginosa 1.204 were investigated. The optimal pH and temperature for enzymatic synthesis reaction was pH 6.8 and 25 degrees C, respectively. By using 1% 7-ADCA, 3% PGME and 4% biomass, about 70% of 7-ADCA was converted to cephalexin under the mentioned conditions.

[Prevention of radiation injury of the lungs by Salvia miltiorrhiza in mice]

The lungs and thymus of mice received X-ray irradiation on the right thorax were observed. It was found that lung injury was lighter and got recovered more rapidly in mice given Salvia miltiorrhiza than that in the control group. Microscopic thymus changes showed no difference in the two groups. The results indicated that Salvia miltiorrhiza could prevent radiation-induced pulmonary injury, but could not prevent thymus injury.

[Rapid isolation of cell-type specific DNA binding proteins]

We had previously found a cell-type specific DNA-binding protein of approximately 150,000 using the southwestern blot technique which was found to be a regulatory factor for activation of N-ras oncogene. In this paper, we describe a modified gel elution method for isolation of this protein using mini-slab gel electrophoresis and silver staining for identification. This method is rapid, economical and preserves the DNA-binding activity of the protein as determined by nitrocellulose filter-binding assay and mobility-shift assay. It is suitable for isolation of proteins in small quantities.

[An allergy prevalence survey in population of 10,144 people]

An retrospective investigation of allergic History was conducted in 10,144 persons in Shen-li Oil Field. The total allergy rate was 40.12%. Women presented a significantly higher prevalence than men. The results showed that allergic disease is the most frequent and common one in our country. Of the thirty common allergic disease urticaria appeared to be the leading one, reaching 23.27%. Following it are drug allergy (10.33%), contact dermatitis (9.72%), allergic rhinitis (6.32%), food allergy (4.98%), migraine (4.15%) and asthma (3.84%).

[Pharmacological action of various processed Mylabris phalerata Pallas]

We have compared the acute toxicity, sub-acute toxicity and in vitro and in vivo anti-tumor action of the rude drug, stir-fried with rice, and alkali-processed drugs of Mylabris phalerata before and after removing the head, feet and wings. The results indicate that the toxicity of the processed drugs is lower than that of the rude ones; the toxicity becomes higher without head, feet, and wings; and the alkali-processing method is better than stir-frying with rice recorded in the pharmacopeia.

[Effect of ke-tang-Ling administration on the function of pancreatic islets cells in non-insulin-dependent diabetes mellitus]

Radioimmunoassay methods were modified for insulin(IRI), C-peptide (IRCP) and glucagon (IRG) in the clinical investigation on normal subjects and 38 patients with non-insulin-dependent diabetes mellitus (NIDDM). In the control group, the peaks of glucose and IRI appeared 1 hour after glucose was taken. IRCP peak, however, appeared 1 hour later. IRG showed its maximum value on fasting and then reached its lowest point at the second hour after glucose loading. The authors' interests were focused on the changes of blood glucose, IRI, IRCP, and IRG in oral glucose tolerance test (OGTT) before and after Ke-Tang-Ling (KTL) was administered in NIDDM. The results demonstrate that the glucose levels and undercure areas at various phases in OGTT were significantly decreased (P less than 0.01) in comparison of before and after the treatment with KTL in NIDDM (including obese and non-obese groups). In non-obese group, however, IRI, IRCP, and their undercure were remarkably increased (P less than 0.01). In obese group their values were decreased. It suggests that KTL plays a therapeutic role in decreasing blood glucose in non-obese NIDDM. The mechanism involved in this process may be related to its stimulating effect. IRG levels were decreased also (P less than 0.01) after the treatment with KTL in both obese and non-obese NIDDM, suggesting an inhibitory effect on glucagon secretion from alpha cells in pancrease.

[Separation of 20(S)-ginsenoside-Rg2 and its 20(R) epimer by reversed phase low pressure column (Rp-18) chromatography]

20(S)-Ginsenoside-Rg2 and its 20(R) epimer were successfully separated using reversed-phase low pressure column (Rp-18) chromatography. The method has proved very convenient and rapid.

[Changes of adrenoceptor density in heart and brain and the reactivity of isolated pulmonary artery ring in atherosclerotic rabbit]

The alpha-adrenoceptor density in cerebral cortex and brain stem as well as the beta-adrenoceptor density in heart were measured by radioligand binding assay in normal rabbits (group 1), atherosclerotic rabbits (group 2) and atherosclerotic rabbits treated orally with aspirin 20 mg/kg daily for 16 wk (group 3). The results showed that the beta-receptor density and the KD values of the hearts among the 3 groups and the alpha-receptor density and KD of brain stem between groups 1 and 2 were not significantly different except that the alpha-receptor density in group 3 was decreased slightly. The number of alpha 1-receptor of cerebral cortex was decreased more in group 2 than that in group 3. The contractile responses of isolated pulmonary artery ring by NE were similar among the 3 groups but the reactivity to 5-HT in group 3 was increased significantly.

Origin of ultraviolet damage in DNA

A novel ultraviolet (u.v.) footprinting technique has been used to analyze the formation of u.v. photoproducts at 250 bases of a 5 S rRNA gene under conditions where the gene is either double or single-stranded. Because many more types of u.v. damage can be detected by the u.v. footprinting technique than has been previously possible, we have been able to examine in detail why certain bases in DNA are damaged by u.v. light while others are not. Our measurements demonstrate that the ability of u.v. light to damage a given base in DNA is determined by two factors, the sequence of the DNA in the immediate vicinity of the photoproduct, and the flexibility of the DNA at the site of the photoproduct. For pyrimidines, the predominant photoreaction in double-stranded DNA involves covalent dimerization between adjacent pyrimidine residues. Dimerization is much easier in melted DNA because the geometrical changes required for adjacent pyrimidine residues to dimerize are easier in single-stranded DNA. The absorption of a u.v. photon cannot simultaneously induce the geometrical changes required for adjacent pyrimidines or other bases to dimerize with one another. Rather, upon the absorption of a u.v. photon, only those thermally excited bases that are in a geometry capable of easily forming a photodimer during excitation, can photoreact. In contrast to adjacent pyrimidines, non-adjacent pyrimidines (pyrimidines flanked on either side by a purine) do not readily form u.v. photoproducts in double-stranded DNA. Because photoreactions at non-adjacent pyrimidine residues are greatly enhanced in single-stranded DNA, their failure to form in double-helical DNA is attributed to torsional constraints imposed by the double helix which make it difficult for non-adjacent pyrimidines to adopt a geometry necessary for photoreaction. Although purines are believed to be resistant to u.v. damage, our measurements demonstrate that at moderate u.v. dosages purines which are flanked on their 5' side by two or more contiguous pyrimidines readily form u.v. photoproducts in double-stranded DNA. Flanking pyrimidines appear to activate purine photoreactions by transferring triplet excitation energy to the purine. Melting of the DNA helix greatly inhibits the ability of flanking pyrimidines to activate purine photoreactions, presumably by disrupting intimate orbital overlap required for triplet transfer.

[Changes of glomerular fixed anionic charge sites in adriamycin nephrosis in rats]

A single intravenous injection of adriamycin (5mg per kg.) into rats induced nephrosis. In the various periods of the model, alterations of glomerular anionic sites stained with colloidal iron were analyzed quantitatively by image analyzer for the first time at home and abroad. The results showed that there was a significant decrease in glomerular anionic charge sites at 3 hours after administration of adriamycin as compared with that of the control animals (P less than 0.01). Marked loss of the anionic charge sites preceded the onset of proteinuria and was steadily increasing along with progress of the disease. The results suggest that loss of glomerular anionic charge sites may play an important role in the development of proteinuria in nephrotic syndrome.

[Ilexonin A may be a slow calcium channel blocker]

Ilexonin A is an effective compound isolated from Ilex pubescens Hook. et Arn. It has been used in the clinic to treat cardiovascular diseases such as cerebral embolism and myocardial infarction. Experimental studies have shown that it inhibited thrombosis, platelet adhesion, and platelet aggregation and 5-HT release induced by collagen, ADP or A23187 in vitro and in vivo. The inhibitory effect of platelet aggregation induced by A23187 was reduced by adding CaCl2 (1mM) to the medium. It suggests that the effects of llexonin A on platelet function are possibly related to calcium. The present experiments were designed to investigate the effects of Ilexonin A on thrombin-induced Ca2+ fluxes of platelets, in which quin-2 was used to measure the cytoplasmic Ca2+ concentration. The results indicated that the free calcium concentrations of resting platelets and the platelets activated by thrombin were 78.65 +/- 7.74 nM and 871.10 +/- 123.63 nM respectively. After adding EGTA (lmM) to the medium, the calcium concentrations reduced to 34.75 +/- 7.77 nM and 50. 86 +/- 7.44 nM. Ilexonin A and verapamil markedly inhibited the thrombin induced Ca2+ influx. The IC50 was 76.8 microM and 67.5 microM respectively. But both had no effect on thrombin-induced Ca2+ release from dense tubular system. It suggests that Ilexonin A acts most likely as a calcium slow channel blocker.