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Seminal vesicle protein IV (SV-IV) is a secretory anti-inflammatory, procoagulant, and immunomodulatory protein produced in large amounts by the seminal vesicle epithelium of the rat under the strict transcriptional control of androgen. In particular, this protein was shown to possess the ability to markedly inhibit in vivo the humoral and cell-mediated immune responses of mice to nonbacterial cellular antigens (sheep erythrocytes and spermatozoa). We report data that demonstrate that in mice treated with SV-IV and infected with Salmonella enterica serovar Typhimurium, SV-IV is able to downregulate some important immunological and biochemical parameters that serovar Typhimurium normally upregulates in these animals. This event did not correlate with a lower bacterial burden but was associated with a markedly increased one (300%). Furthermore, the treatment of mice with SV-IV alone also produced a significant increase in the rate of mortality among serovar Typhimurium-infected animals. The mechanism underlying these phenomena was investigated, and the strong immunosuppression produced by SV-IV in serovar Typhimurium-infected mice was suggested to be the basis for the increased rate of mortality. The SV-IV-mediated immunosuppression was characterized by a decrease in the humoral and cell-mediated immune responses, altered lymphocyte-macrophage interaction, downregulation of cytokine and inducible nitric oxide synthase gene expression, inhibition of macrophage phagocytosis and intracellular killing activities, and absence of apoptosis in the splenocyte population of SV-IV- and serovar Typhimurium-treated mice. The immunosuppressive activity of SV-IV was specific and was not due to aspecific cytotoxic effects. SV-IV-specific receptors (K(d) = 10(-8) M) occurring on the macrophage and lymphocyte plasma membranes may be involved in the molecular mechanism underlying the SV-IV-mediated immunosuppression. Some results obtained by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay also revealed a functional impairment of mitochondria (a decrease in mitochondrial dehydrogenase activity), thus indicating the possible implication of these organelles in the immunosuppressive process.

In our present study we have examined the phagocytosis by polynucleates towards bacteria exposed to macrophages or lymphocytes. Our results show that for almost all the bacterial strains, the contact with lymphocytes determines changes in hydrophobicity correlated to variations in the possibility of being phagocytized and of more significant intracellular killing with respect to bacteria treated with macrophages.

Many studies shown that the capacity of the bacteria to adhere to the host cells is a fundamental requisite to the onset of any colonization process and hence infection. Our results shown that E. coli strains from patients with recurring urinary tract infections showed a high degree of surface hydrophobicity, correlated with the presence of numerous fimbriae with respect to a control group.

This paper investigates the design of new or existing structures equipped with hysteretic dissipation devices by using simplified nonlinear analysis based on the definition of the strength reduction factor. In this paper a plane reinforced concrete frame retrofitted by means of properly designed dissipative braces is analysed. In particular, two different conditions are considered: when the bare frame behaves elastically or inelastically. The bare frame and the strengthened frame are subjected to nonlinear static analysis in order to obtain the corresponding strength reduction factor. This simple study is repeated varying the brace mechanical properties in order to investigate the effects on the strength reduction factor. The N2 method is employed to propose a procedure to follow in order to perform strength and ductile checks of the braced system. Finally some hints are given with respect to the possibility of design with equivalent damping and stiffness, according to the American guidelines FEMA 273 and 274.