calcimycin and Bacterial-Infections

Prostaglandins (PGs) and thromboxane (TX) are important mediators of inflammation. Recent studies revealed that PG and TX synthesis is controlled by the regulation of PG- and TX-synthesizing enzymes. In this study, we examined the TX synthesis and the expression of TX-synthesizing enzymes in activated peripheral polymorphonuclear leukocytes (PMNs) obtained from children with bacterial infection. Blood samples were obtained from controls and patients with bacterial infection. A23187-stimulated production of TXB(2), a stable metabolite of TXA(2) in PMNs, was measured by a specific radioimmunoassay. The mRNA expression of cytosolic phospholipase A(2) (cPLA(2)), cyclooxygenase (COX)-1, COX-2, and TXA(2) synthase was determined by RT-PCR. The synthesis of TXB(2) in PMNs was significantly increased in the patients [925.0 (550.0-1100.0) pg/10(6) cells], compared with the controls [550.0 (450.0-775.0) pg/10(6) cells]. The mRNA expression for cPLA(2) and COX-2 in PMNs was also enhanced in the patients. The results indicate that TX production in PMNs is significantly increased through possible transcriptional mechanisms of cPLA(2) and COX-2 during bacterial infection in children. The upregulation of TXA(2) synthesis may contribute to the process of acute inflammatory reaction caused by bacterial infection.

Topics: Adolescent; Anti-Bacterial Agents; Bacterial Infections; Calcimycin; Case-Control Studies; Child; Child, Preschool; Cyclooxygenase 1; Cyclooxygenase 2; Cytosol; Female; Humans; Infant; Inflammation; Isoenzymes; Male; Membrane Proteins; Neutrophils; Phospholipases A; Phospholipases A2; Prostaglandin-Endoperoxide Synthases; RNA, Messenger; Thromboxane A2; Thromboxane B2; Up-Regulation

Many studies have examined the impact of genital tract infections on male fertility; however, the effect of bacteriospermia on sperm quality is still controversial. Bacterial infections are more frequently found in semen samples from asymptomatic infertile patients than in those from fertile men. Bacteriospermia is also a common problem of male partners from couples undergoing IVF. Therefore, the effects of microorganisms on human sperm acrosome reaction of oocytes have been studied in vitro and in vivo. Incubation of spermatozoa with Escherichia coli or Mycoplasma hominis in vitro resulted in reduced sperm motility and inducibility of acrosome reaction (delta AR) after exposure to calcium ionophore A23187. To show possible effects of E. coli and mycoplasma species on sperm functions in vivo, data from 488 patients were evaluated, in whose ejaculates microbiological examinations and determinations of acrosome reaction after exposure to low temperature had been performed. U. urealyticum and E. coli were found in semen samples from 52 and 31 men, respectively. M. hominis was only present in a minor number of samples and was not included in this study. Semen concentrations of E. coli and U. urealyticum ranged between 500-100,000 cfu x ml-1 and 100-80,000 cfu x ml-1. No correlation was found between delta AR and concentration of bacteria (Spearman rank correlation coefficient, E. coli: r-0.081, P = 0.6644; U. urealyticum: r = -0.081, P = 0.5698). In 69% of cases with U. urealyticum infection and reduced inducibility of acrosome reaction, this sperm function was normal after antibiotic therapy. However, improvement of acrosomal function may only be due to intra-individual variations of acrosome reaction. While E. coli and mycoplasma species affect sperm functions in vitro, the present data and a review of the literature fail to demonstrate similar effects in vivo.

Topics: Acrosome; Bacterial Infections; Calcimycin; Escherichia coli; Humans; In Vitro Techniques; Ionophores; Male; Male Urogenital Diseases; Mycoplasma hominis; Semen; Sperm Motility; Spermatozoa; Ureaplasma urealyticum

Newborns are predisposed to neutropenia and thrombocytopenia during bacterial sepsis. The presence of peripheral cytopenias during overwhelming infection may be secondary to decreased hematopoietic growth factor production during states of increased demand. We therefore examined circulating levels of granulocyte-colony stimulating factor (G-CSF) and IL-3, production of G-CSF and IL-3 from unstimulated and stimulated mononuclear cells (MNC), expression of G-CSF and IL-3 genes during unstimulated and stimulated conditions, and equilibrium and binding of G-CSF receptors on mature effector peripheral blood cells of adults and neonates. Serum from cord and adult peripheral blood contained negligible amounts of both G-CSF (less than or equal to 50 pg/mL) and IL-3 (less than or equal to 5 pg/mL). Constitutive supernatant levels of G-CSF and IL-3 from cord and adult unstimulated MNC were also undetectable. However, there was a significant difference in G-CSF and IL-3 production from stimulated cord and adult MNC. Supernatants from stimulated adult MNC had significantly more G-CSF (p less than 0.007) and IL-3 (p less than 0.02). Additionally, Northern blot hybridization and densitometry of autoradiographs demonstrated significantly more G-CSF and IL-3 mRNA transcripts from adult than from cord MNC. Lastly, affinity, binding, and number of G-CSF receptors on cord and adult peripheral effector cells were equal. These data suggest that, during states of increased demand, cord MNC produce less G-CSF and IL-3 than do adult MNC and have an associated reduction in their respective mRNA transcripts. These findings may have implications in the pathogenesis of neonatal cytopenias during states of increased demand, such as sepsis.

Topics: Adult; Bacterial Infections; Calcimycin; Fetal Blood; Gene Expression; Granulocyte Colony-Stimulating Factor; Humans; In Vitro Techniques; Infant, Newborn; Interleukin-3; Leukocytes, Mononuclear; RNA, Messenger; Tetradecanoylphorbol Acetate

Histamine release from human basophil leukocytes was triggered by Staph. aureus, Salmonella enteritidis, non-haemolytic streptococci, or E. coli. Influenza A virus was found to enhance the mediator release and the effect was caused by synergism, since the virus did not induce release of histamine per se. This potentiating effect of the virus was seen both when the bacteria-induced histamine release was IgE-dependent (i.e. patient sensitized to the bacterium) and when the bacterium caused mediator release by a non-immunological mechanism independent of IgE (putative sugar-lectin mediated). Histamine release induced by anti-IgE and calcium ionophore or agarose-beads was also enhanced in the presence of the virus. These findings indicate that influenza A virus potentiates both IgE- and non-IgE-mediated histamine release induced by bacteria and other stimulators.

Topics: Bacterial Infections; Basophils; Calcimycin; Escherichia coli Infections; Histamine Release; Humans; Immunoglobulin E; In Vitro Techniques; Influenza A virus; Salmonella Infections; Staphylococcal Infections; Streptococcal Infections

The production of three kinds of oxygen radicals (superoxide, hydrogen peroxide, and hydroxyl radicals) by neutrophils from patients with bacterial infection or rheumatoid arthritis was measured. The stimulators used in this study were opsonized zymosan (1 mg/ml), phorbol myristate acetate (20 ng/ml), A23187 (1 microM), and platelet activating factor (1 microM). Oxygen radical production by neutrophils from patients with rheumatoid arthritis was not significantly different from that of the control group. Hydrogen peroxide production by the neutrophils from patients with bacterial infection was significantly enhanced by only opsonized zymosan, but the production of the other kinds of oxygen radicals was not. Cytochalasin B reduced the production of hydrogen peroxide induced by opsonized zymosan more markedly than that of any other kind of oxygen radical. The measurement of hydrogen peroxide is suggested to be the most accurate indicator of the enhancement of intracellular production of oxygen radicals by neutrophils during infection.

Topics: Arthritis, Rheumatoid; Bacterial Infections; C-Reactive Protein; Calcimycin; Cytochalasin B; Free Radicals; Humans; Hydrogen Peroxide; Leukocyte Count; Neutrophils; Oxygen; Platelet Activating Factor; Superoxides; Tetradecanoylphorbol Acetate; Zymosan