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The object of our study is to demonstrate that some components of M. tuberculosis, such as cord factor or mycolic acid or whole bacteria can prolong cell survival compared to controls. The cells treated with cord factor or mycolic acid at a concentration of 5 microg/ml were 65+/-8% viable reaching 70+/-8% at a concentration of 10 microg/ml. The cells treated with heat killed mycobacteria were 70+/-8% viable; while control cells exhibited a viability 50+/-7%. Conversely, tuberculostearic acid induced early cell death. The results also demonstrated a dose-dependent effect on the viability or induction of macrophage apoptosis. We also showed that prolonged viability of the treated cells with mycolic acid or cord factor (+20+/-4% and +25+/-5%, respectively) was correlated with a significant increase in Bcl-2 expression. The treated cells with whole bacteria presented a Bcl-2 expression of 40+/-6%, while Fas expression was not changed compared to controls. This study confirm that at the site of mycobacterial infection, necrosis, apoptosis or prolonged survival of the cells depend on the quantity and quality of the molecules expressed by the mycobacteria; whether necrosis or apoptosis or prolonged survival is more or less favorable to the host likely depends on several factors regarding the inflammatory and immune response, both markedly stimulated by mycobacteria.

Our results indicate that benzodiazepine (Bz) treatment time, greater than 2–3 months, induce a decrease of both specific and nonspecific responses. Mice treated for different times with diazepam or chlordemethyldiazepam showed decreased survival to experimental Salmonella typhimurium infections after three months of treatment. Adherence, expressed as the polymorphonuclear cells (PMN) capacity to attach to nylon wool, was impaired after 7 days of treatment. Longer treatments further increase this impairment. PMN from mice treated with Bz for 90 days also demonstrate on impaired chemotaxis and phagocytosis for Saccharomyces cerevisiae . Monocytes from mice treated for 7 days secreted more IL-1 α then controls; the antibody titer in mice given to prolonged treatment progressively diminished compared to controls. Con A or LPS stimulated lymphocytes showed an increase of H 3 -thymidine incorporation from mice treated for a short time and conversely a decreased incorporation when taken from mice that underwent longer treatments. Benzodiazepines were therefore found to affect PMN chemotaxis and phagocitosis, general immunity and survival of mice to infections.

From the experiments carried out in this study on mice kept on a 17.5% alcoholic diet (ethanol) for more than 90 days, a clear-out decrease was found in all the protective responses studied. In fact, the data show: (a) increased mortality with increased number of circulating bacteria; (b) diminished adherence and migrational capacity of polymorphonuclear leukocytes; (c) diminished phagocytosis index; (d) reduced release of cytokines from lymphocytes and monocytes; and (e) diminished response of lymphocytes to polyclonal stimuli (concanavalin A, lipopolysaccharide).

Our study considered the possibility of modifying the functional response of human neutrophils, of mouse lymphocytes and macrophages treated with phospholipids having different polar groups, different isomerisms with saturated and unsaturated fatty acids from C12 to C20 carbon atoms. The results are as follows. a) Most of the phospholipids containing fatty acids from C12 to C20 cause inhibition of the blastogenic capacity of the polyclonal activators tested. b) The phospholipids tested cause a decrease in adherence of polymorphonuclear leukocytes with the exception of the phosphatidyl-choline containing saturated and unsaturated fatty acids. c) A decrease in polymorphonuclear leukocytes migrational capacity almost always occurs. d) The cells treated with L-phosphatidyl-ethanolamine having fatty acids from C14 to C17 show an increase in chemiluminescence; those treated with phosphatidyl-choline and L-phosphatidyl-glycerol show a decrease of the chemiluminescence; L-phosphatidic acid and L-phosphatidyl-ethanolamine having Microbial fatty acids (FAs) at C16 cause a decrease in the formation of phagolisosomes in the macrophages tested.

Brucellosis is endemic in the Mediterranean area. In spite of the false negative results, the standard agglutination test remains the routine test for the diagnosis of brucellosis in southern Italy. We present a case of a patient with undulant fever and erythema nodosum-like skin lesions, with negative serum agglutination test, but isolated positivity of the ELISA test for anti-Brucella IgM. A diagnosis of brucellosis for this patient was supported by the anamnestic and clinical data, and by the response to therapy. This case and a review of the literature urge us to consider the ELISA test indispensable for the serological diagnosis of brucellosis.

Microgram amounts of protein SV-IV, a major secretory protein produced by adult rat seminal vesicle epithelium, markedly decrease the mouse humoral immune response to cellular xenogeneic or allogeneic antigens (sheep red blood cells (SRBC) or mouse epididymal spermatozoa). The significant reduction in the total number of splenocytes and their main cell subsets in SRBC-immunized mice, the dramatic decrease in the number of Ia(+) splenic T cells and the marked inhibition of splenocyte ability to respond in vitro to polyclonal mitogen stimuli suggest that the macrophage accessory cells are the primary target of the SV-IV immunosuppressive activity in vivo. Moreover, the infection of SV-IV-treated mice with Salmonella typhimurium produced an increased mortality of the experimental animals associated with a marked decrease of the phagocytic and intracellular killing activities of their peritoneal macrophages.

Study design The case report of a 60-year-old man with late onset back pain after lumbar spine fusion is presented. Objective To report the rare complication of bilateral pedicle stress fractures after instrumented posterolateral lumbar fusion. Summary of background data A 56-year-old man underwent revision spinal surgery for ongoing back pain secondary to pseudoarthroses. A posterolateral L4-S1 instrumented fusion using pedicle screws was performed. Autologous bone graft was applied to the decorticated lateral masses. The internal fixation was removed 2 years later, at which time plain radiographs showed that the fusion mass was solid. At the age of 60 years, the man presented with worsening back pain. Plain radiographs and computed tomographic scans demonstrated bilateral L4 pedicle stress fractures. A bone scan indicated that these were recent in origin. Method The clinical assessment was undertaken by the senior author and surgeon. Investigations included plain radiography, computer tomography, and scintographic imaging. A systematic literature review of the relevant publications was performed. Results In the reported patient, bilateral pedicle stress fractures developed 2 years after pedicle screw removal from an L4-S1 instrumented posterolateral lumbar spine fusion. This occurred at the uppermost level of the fusion mass. Conclusions The pedicle is the weakest point in the neural arch after posterolateral fusion. Although movement continues at the level of the disc space anteriorly, the pedicle is susceptible to fracture. Pedicle fracture is a rare late complication of posterolateral lumbar spine fusion.

The production of hsp and apoptosis of leukocytes in the peripheral blood of animals naturally infected with Brucella spp or treated with the vaccine Brucella abortus 19 have been investigated in this study. Cytokines able to induce phagocytic activity in macrophages of non treated healthy animals were found in the supernatant of bovine leukocytes cultivated in vitro. A long-lasting antibody response against hsp 60 kDa and 27 kDa, which lasts a long time, is induced in naturally infected animals, while in animals vaccinated with B. abortus 19 we detected an antibody response against hsp 60 and 70 kDa which is much shorter, disappearing in two months. During the early phase of infection, lymphocytes and monocytes of naturally infected animals show a delay of apoptosis in vitro compared to the same cells coming from healthy controls and vaccinated animals.

This study has assessed the changes in the polarization fluorescence of 1,6-diphenyl-1,3,5-hexatriene in the splenic membrane of mice treated with clindamycin, penicillin, cefoxitin, cefamandole, cephaloridine, tetracycline, and erythromycin. The data show that most of the antibiotics tested modified membrane activity, as was shown by the changes in membrane microviscosity parameters.

The continuous stimulation of the immune system using cell wall antigens from Brucella melitensis was found to cause both quantitative and qualitative changes in circulating lymphocyte populations in mice. Animals were inoculated in the hind legs with antigens on alternate days for varying lengths of time. During a two-month period, we saw a higher number of circulating lymphocytes, with an increase in the number of CD4+ cells (L3T4+) and B lymphocytes (I-Ad). After two months, a drop in the overall number of circulating lymphocytes occurred, with a decrease in CD4+ cells and an increase in CD8+ cells. During the first two months, we observed a size increase in popliteal lymph nodes and an elevated humoral response. The response then waned with the declining CD4+ cells. In the first two months, the treated animals also showed an in vitro response to two mitogens, concanavalin A and lipopolysaccharide and to the cell wall fraction, after which the treated animals showed a decreased response.

The immunoregulatory role of prolactin (PRL) has been well established. In order to clarify if the hormone is also able to stimulate a protective activity against pathogens-induced infections we have studied the modifications of the infective capacity of Salmonella typhimurium induced in mice by repeated treatments with ovine PRL. A significant dose-dependent reduction in the mortality rate was observed in comparison to controls. This activity is probably related to the observed increases in phagocytosis and intracellular killing of the peritoneal macrophages and chemotaxis of the peritoneal granulocytes induced by the hormonal treatment. On the contrary, the number of leukocytes in blood was not modified by PRL treatment excluding a mobilization of cells from other districts. Our findings confirm the existence of a linkage between the neuroendocrine and immune systems suggesting a possible role for PRL in the regulation of non-specific immune response.

Rabbits immunized for 6 months with different amounts of sterile human serum showed weight loss and a decrease in leukocytes. The lymphocyte population reacting to ConA contained autoreactive cells capable of causing 51Cr release from labeled cells from a culture consisting of splenic and peripheral lymphocytic cells from the same animal.

To date no knowledge of the incidence of scoliosis in adults and its relationship to low-back pain is available. In order to arrive at an understanding of low-back pain in adult scoliosis, a study of 5000 intravenous pyelograms was performed. The incidence of lumbar and thoracolumbar curves was 2.9%. One hundred and fifty-nine of the 189 patients found to have scoliosis were contacted. The incidence of back pain was 59% (similar to that in the general population). Back pain was subdivided into mild (44%), moderate (49%), or severe (7%). The curve was subdivided into three categories: 10-24 degrees, 25-44 degrees, and 45+ degrees. Of the 82 idiopathic curves with pain, 64 were in group 1, 15 in group 2, and 3 in group 3. Forty-three percent had mild pain, 50% had moderate pain, and 7% had severe pain. As the degree of curvature increased, the severity of pain increased, especially for curves of more than 45 degrees. Patients without back pain tended to have smaller curves. the presence of facet sclerosis correlated with a history of pain in 64%. There was a high correlation between radiologic changes at the curve apex and pain. Age bore no relationship to the incidence of pain.

Female mice were maintained on lipid diet for 20 days. The nonspecific and immunological defense capability was determined by in vitro and in vivo methods. It was found that mice held mostly on a lipid diet demonstrate an all-round lowered response. Following 20 days of lipid diet the splenocytes exhibit: (1) an inversed lipid-protein ratio; (2) an inability to respond to sheep erythrocytes; (3) a reduction in [3H] thymidine incorporation in splenocytes stimulated with lipopolysaccharide (LPS) or with concanavalin A; (4) a reduction in the number of cells bearing surface immunoglobulins in splenocytes stimulated with LPS; (5) an inhibition of phagocytosis and intracellular killing in macrophages; (6) a lowering in granulocyte chemotaxis and adherence capacity; (7) a higher mortality to LPS after loading with galactosamine; and (8) a lowered complement activity even following LPS activation.

A study was conducted on the granulocytic phagocytosis of bacterial aggregates obtained under ideal environmental conditions. For the strains studied, aggregation was favored by low salt concentrations, low pH and temperatures between 30 degrees C and 40 degrees C. Our results show that the phagocytic capacity of granulocytes depends on the type and size of these aggregates. Those formed by a smaller number of cells are more easily phagocytized than the larger ones.