Differential induction of macrophage-derived cytokines by live and dead intracellular bacteria in vitro

Marked differences in the abilities of living and heat-killed Brucella abortus and Listeria monocytogenes organisms to induce production of tumor necrosis factor alpha by in vitro-cultured macrophages were observed. Interleukin-1 and interleukin-6 appeared to be under different control. The results are discussed in relation to the induction of gamma interferon-producing Th1 cells and acquired cellular resistance to infection by living vaccines but not killed vaccines.

Signalling the molecular stress response to nephrotoxic and mutagenic cysteine conjugates: differential roles for protein synthesis and calcium in the induction of c-fos and c-myc mRNA in LLC-PK1 cells

Nephrotoxic and mutagenic cysteine conjugates (NCC) are activated by the enzyme cysteine conjugate, beta-lyase, to reactive acylating species which bind covalently to cellular macromolecules. We now show that an early event after treatment of LLC-PK1 cells with NCC is the induction of mRNA for both c-fos and c-myc. Treatment with S-(1,2-dichlorovinyl)-L-cysteine (DCVC) induced c-fos (53-fold) and c-myc mRNA (20-fold) and increased transcription about 3-fold for both genes. Covalent binding was required for induction of both mRNAs. Dithiothreitol partially prevented induction of both c-fos and c-myc RNA. Buffering the DCVC-induced increase in cytosolic free calcium had no effect on c-fos mRNA, but partially blocked c-myc mRNA induction. Cycloheximide blocked the induction of c-myc mRNA in the absence of an effect on c-fos induction. The data suggest that the increase in c-fos mRNA is a primary response to DCVC toxicity and occurs without a requirement for protein synthesis or an increase in intracellular free calcium. In contrast, c-myc induction requires protein synthesis, suggesting that the presence of another primary response factor may regulate induction either transcriptionally or posttranscriptionally. The data suggest that different signalling pathways regulate induction of c-fos and c-myc mRNA in response to stress caused by reactive acylating species.

[Protective effects of ginsenoside on myocardiac ischemic and reperfusion injuries]

Thirty mitral valvular surgical patients were randomly divided into three groups for study of protective effects of Ginsenoside on myocardiac ischemic and reperfusion injuries. In GI, 11 patients (controls), no Ginsenoside was used, in GII, 11, Ginsenoside in total was added into the cardioplegic solusion made in our hospital, and in GIII, 8, instead of Ginsenoside in total Ginsenoside Rb was added. During operation comparative studies were made of pre- and postoperative cardiac functions with intraoperative transesophageal echocardiography and ultrastructures of myocardiac cells with electromicroscopy. We conclude that both Ginsenoside in total and Ginsenoside Rb have protective effects on myocardiac ischemic and reperfusion injuries in open heart surgery, and the effect of Ginsenoside in total is even better than that of Ginsenoside Rb.

Analysis on the distribution of bases in 1487 human protein coding sequences

The occurrence frequencies of bases A, C, G and T, denoted by a, c, g and t, respectively, in 1487 human protein coding sequences have been calculated and analyzed. The analysis has been performed by a diagrammatic method presented recently, in which each coding sequence is represented by a point in 3-D space. The distribution of points gives the observer an overall and intuitive picture of the base frequencies. The distance between a point and the origin of the co-ordinate, which corresponds to the case of a = c = g = t = 1/4, is called the radical distance. The radical distribution of 1487 points in 3-D space has been found to be normal, with the center basically coinciding with the origin of the co-ordinate. We have found that among 1487 coding sequences, an empirical rule a2 + c2 + g2 + t2 < 1/3 holds for 1486 sequences. The only sequence in which the above rule does not hold is the one coding for the human parathymosin protein. The composition of amino acids and the structural class of this protein has been studied in some detail.

[Risk factors of prostate cancer--a matched case-control study]

A 1:2 matched case-control study was used to determine the risk factors of prostate cancer. Twenty-seven cases of prostate cancer were matched with an equal number of other malignant tumor cases (non-urological tumor) and other urological cases (non-malignant tumor). Both study and control groups were the same in age, sex, race, and day of admission. All of these patients were treated in the First Affiliated Hospital of West China University of Medical Sciences. The questionnaire was used to survey the both groups of patients. Such data as diet, lifestyle, marital status and past history of other prostate diseases were obtained. Single factor analysis and multiple conditional logistic regression analysis were used to estimate the relative risk (RR), 95% confidence interval (95% CI) and P values. Statistical analysis was performed using the Egret, Epilog soft ware. The results were as follows: 1. Increasing dietary vitamin A was associated with a significant decrease in the risk of prostate cancer (RR = 0.948, 95% CI = 0.9309-0.9947, P = 0.029). This factor also showed dose response gradients. The relative risk was decreasing with exposure dose increasing. 2. The positive previous prostate history, such as prostatitis and benign prostate hyperplasia, increased the risk of prostate cancer (RR = 6.385, 95% CI = 1.046-38.97, P = 0.045). 3. Another finding in the widower, divorce and remarried men (RR = 4.312, 95% CI = 1.367-13.6, P = 0.013). And 4. There was no relationship between the risk of prostate cancer and dietary fat intake, vasectomy, socioeconomic status, familial malignant tumor history, smoking and alcohol consumption.(ABSTRACT TRUNCATED AT 250 WORDS)

Endogenous gamma interferon mediates resistance to Brucella abortus infection

Depletion of endogenous gamma interferon (IFN-gamma) with anti-IFN-gamma monoclonal antibody resulted in increased numbers of Brucella abortus in the spleen and liver of infected CBA mice. This increase was accompanied by a decrease in splenomegaly and a lower proportion of macrophages in the spleen. Furthermore, treatment of recipient mice with anti-IFN-gamma antibody blocked the adoptive transfer of resistance with immune T cells. Together, the results indicated that endogenous IFN-gamma plays an important role in mediating resistance to primary and secondary Brucella infection.

Cytokine production in the murine response to brucella infection or immunization with antigenic extracts

In order to induce acquired cellular resistance (ACR) to facultative intracellular bacterial pathogens, infection with live organisms is required. It is possible that different cytokine responses to live bacteria or their extracted antigens could account for their different abilities to induce ACR. Therefore, mice were infected with live attenuated Brucella abortus vaccine strain 19, and their ability to produce cytokines, both in vivo and in vitro, was investigated over 12 weeks of infection. This was compared with the response to injection of soluble brucella proteins (SBP). During infection, serum levels of interleukin-6 (IL-6) were markedly increased over a period of 4 weeks during the peak of infection. SBP plus adjuvant induced a transient increase in serum IL-6. IL-1 and tumour necrosis factor-alpha (TNF-alpha) remained undetectable in both instances. Spleen cells taken at intervals after infection and cultured with brucella antigens produced high titres of IL-6, IL-1 and TNF-alpha. Immunization with SBP was less efficient than live infection at inducing these cytokines. Of the characteristically T-cell-derived lymphokines, interferon-gamma (IFN-gamma) production rose 2 weeks after infection, peaking at 6 weeks, while IL-2 was not detected until 6 weeks post-infection. Granulocyte-macrophage colony-stimulating factor (GM-CSF) was produced in substantial amounts, but IL-3 production was minimal. In contrast, spleen cells from mice immunized with SBP produced IL-2 but failed to produce IFN-gamma. The implications of these results for the induction of ACR are discussed.

Interleukin-6 production during chronic experimental infection

The appearance of interleukin-6 (IL-6) in serum of mice was monitored during the course of chronic infection with either Brucella abortus vaccine strain 19 or a virulent Mycobacterium avium Complex (MAC) isolate. Serum IL-6 during brucella infection was higher than during infection with MAC, despite similar numbers of bacteria. Furthermore, IL-6 titres decreased after the peak of infection, falling to baseline levels before these chronic infections were eradicated. The ability of peritoneal cells or spleen cell suspensions to produce IL-6 under either specific or non-specific stimulus was greatly enhanced by infection. While production of IL-6 by these cultures was apparently mostly independent of T cells, T cells from infected mice could produce an IL-6 response. Thus CD4+ T lymphocytes prepared from mice which had recovered from B. abortus infection, cultured with antigen and antigen presenting cells, resulted in IL-6 production, which was not observed in similarly cultured CD8+ T cells, indicating a role for T cells.

Cytokine response of T-cell subsets from Brucella abortus-infected mice to soluble Brucella proteins

Hot saline extracts of Brucella abortus 19 were separated by successive differential precipitation with 50 and 70% ammonium sulfate, yielding fractions SBP50, with predominantly 36-kDa proteins and a number of medium-sized proteins (26 to 33 kDa), and SBP70, with 14-kDa and lower-molecular-mass proteins. Both fractions stimulated specifically proliferation and cytokine production by spleen cells from brucella-infected mice, although the activity of SBP50 was much higher than that of SBP70. Further separation of SBP50 by a DEAE-Sepharose column resulted in three distinct subfractions which were confirmed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The three subfractions were analyzed for their abilities to induce lymphocytes to proliferate and produce cytokines. The three subfractions were all active but with characteristic differences in magnitude. Subfraction 1 stimulated moderate proliferation, high interleukin 6 (IL-6) production, and relatively low production of gamma interferon (IFN-gamma). Subfraction 2 was the strongest stimulus for proliferation and production of IL-6 and IFN-gamma, while subfraction 3 stimulated moderate cell proliferation, a high level of IFN-gamma, and a low level of IL-6. IL-2 production stimulated by the three subfractions was similar. SBP50 and all three subfractions stimulated purified T cells of both CD4+ and CD8+ subsets to produce IFN-gamma. The production of IFN-gamma by CD8+ T cells to brucella antigens was enhanced with exogenous IL-2.

Comparison and characterization of retinal pericytes and retinal pigment epithelial cells on subcellular IP3-sensitive Ca2+ pools

A comparative study of inositol 1,4,5-trisphosphate (IP3)-induced Ca2+ mobilization in bovine retinal capillary pericytes (BRCP) and bovine retinal pigment epithelial cells (BRPE) was carried out. Both cells were permeabilized with saponin. The two cell types had similar basal levels of [Ca2+]i (130 nM for BRCP, 132 nM for BRPE) and responded to IP3 in a dose-dependent manner. However, when stimulated by various concentrations of IP3 (1-10 microM), the increase in [Ca2+]i of BRCP was always two- to threefold higher than that in BRPE. Subcellular-fractionation studies showed that a single population of IP3 binding site with a high affinity and high specificity of IP3 mainly localized to plasma membrane in these two cell types. Although the dissociation constant of specific [32P]-IP3 binding sites (Kd 1.9-2.8 nM) was similar, the profile of maximal binding capacity (Bmax) of each fraction was markedly different. In comparison, plasma membrane fractions of BRCP were with Bmax of 165 fmol/mg protein versus 90 fmol/mg protein for BRPE membranes. The ATP-dependent Ca2+ uptake and IP3-dependent Ca2+ release were observed in the both plasma membrane fractions. With quantitative correlation, the membrane fraction (2 mg) of BRCP released 0.2 nmol Ca2+ whereas BRPE only released 0.07 nmol Ca2+ with the same dose of IP3 (5 microM). The selectively higher density of IP3 binding sites in coupling to the larger Ca(2+)-release in the membrane of BRCP suggests that the quantity of Ca2+ mobilized is determined by the spatially preferential distribution of membrane-associated IP3 binding sites. These findings may provide an explanation for the differences observed between BRCP and BRPE in IP3-induced DNA replication.

[Female pseudohermaphroditism with a phallic urethra--a case report]

Female pseudohermaphroditism with penile urethra caused by virilizing adrenal tumor in the mother is rare. A case is reported in this article. After operation the diagnosis was verified pathologically. Exposure of a female fetus to endogenous or exogenous androgens before the seventh or eighth week of fetal age may result in male external genitalia. It is emphasized that any cryptorchid phenotypic male born to a virilized mother should be proved by sex chromatin and sex chromosomes to exclude pseudohermaphroditism and that in any case of unexplained female pseudohermaphroditism one should explore the possibility of a maternal virilizing tumor.

[Statistical analysis of age-related macular degeneration (AMD) in the differentiation of symptoms and signs]

Ninety-eight individuals according with entry criterion were allowed to participate in the study. Their clinical symptoms and signs were classified to seven symptoms by means of epidemiology. The results indicated syndrome of vital energy in patient group had more significant than controlled group, the others had not. In the syndrome of deficiency of vital energy, the frequency that the corpalent tongue or margin and tip of the tongue look jagged and the pulse lost its vitality emerged in the patient group surpassed significantly the controlled group. So, we initially considered that traditional Chinese medicine syndrome of AMD patient is mainly the deficiency of vital energy. The happening and development of AMD is probably related to the physique of deficiency of vital energy, it is a key point of determination of treatment with traditional chinese medicine based on differentiation of symptoms and signs.