Decreased expression of the high-mobility group protein T160 by antisense RNA impairs the growth of mouse fibroblasts.

The T160 protein belongs to the HMG-1 box protein family and preferentially binds to non-B-DNA conformations with no sequence specificity. Its exact role has yet to be defined, though it seems to participate in processes involving DNA, such as replication, transcription and recombination. We have used an antisense RNA strategy to investigate its role in cell growth and proliferation.

Suppression of high mobility group protein T160 expression impairs mouse cytomegalovirus replication.

The high mobility group (HMG-1) box proteins bind both non-B-DNA conformations and specific nucleotide sequences. They have been implicated in a wide variety of cellular functions involving DNA, such as transcription, replication and recombination. To determine whether HMG-1 box protein T160 plays a role in virus replication, we employed an antisense strategy to inhibit its expression in NIH 3T3 cells.

Host genotype controls the ability of the ISGF3 complex to activate transcription of IFN-inducible genes.

C57BL/6 mice are unable to express the Ifi 202 type genes upon injection in vivo of multiple dsRNA, poly rl:rC, or IFN-treatment in vitro. For this purpose the 5' terminal flanking region (called the b segment of 804 bp) was linked to a heterologous reporter gene chloramphenicol acetyl transferase (CAT) and transfected into NIH3T3 cells or BLK cells derived from the C57BL/6 strain. IFN-alpha induced strong CAT activity in NIH3T3 but not in BLK cells.

Evaluation of in vitro and in vivo antimicrobial activity of a new topical antiinfective agent.

ST 1103 (Undecyl [4-N,N,N-trimethylammonium-(R)-3- isovaleroyloxy]-butanoate methanesulfonate) is a novel compound endowed with a broad antimicrobial spectrum. ST 1103 is able to inhibit the in vitro growth of Gram-positive bacteria (mean MIC value of 2.60 micrograms/ml), Gram-negative bacteria (mean MIC value of 27.

Characterization of nuclear factors involved in 202 gene induction by IFN-alpha, viruses or dsRNA in murine leukemia cells.

When treated with IFN-alpha, L1210 leukemia cells express high levels of the mouse 202 gene mRNA after a few hours. Three tandem copies of a 43 bp fragment (GAbox) homologous to the IFN-stimulatable response element (ISRE), located in the 5'-flanking region of the 202 gene, were linked to the reporter CAT gene and transiently transfected into L1210 cells. The data suggest that the GA box is sufficient to confer transcriptional inducibility upon IFN stimulation.

Beneficial effects of a novel platelet-activating factor receptor antagonist, ST 899, on endotoxin-induced shock in mice.

The effect of ST 899, a novel platelet-activating factor (PAF) receptor antagonist, on serum tumor necrosis factor (TNF), interleukin-6 (IL-6), and interferon-gamma (IFN-gamma) production as well as on lethality in an experimental endotoxin shock model was investigated in C57BL/6 mice. In this model, animals receiving 40 mg/kg lipopolysaccharide (LPS) (Escherichia coli 055:B5) intraperitoneally were pretreated with ST 899 administered according to two different schedules. ST 899 pretreatment dose dependently reduced the mortality induced by LPS injection.

Trans-activation of the mouse cytomegalovirus immediate early gene enhancer by ras oncogenes.

The ras gene family encodes 21K proteins that reside on the inner face of the plasma membrane and bind GTP and GDP with an equally high affinity. Cotransfection of NIH 3T3 cells with a mammalian expression vector containing a viral Harvey-ras (v-Ha-ras) cDNA, together with a plasmid (pCMVCAT) carrying the immediate early (IE) enhancer of the murine cytomegalovirus (MCMV) linked to the chloramphenicol acetyltransferase (CAT) reporter gene strongly stimulated CAT activity. Basal levels of pCMVCAT expression as well as trans-activation by v-ras plasmid were both inhibited by cotransfection of an expression vector containing the dominant inhibitory mutant gene Ha-ras Asn-17.

LPS-induced serum TNF production and lethality in mice: effect of L-carnitine and some acyl-derivatives.

The effect of L-carnitine and some of its acyl derivatives on serum TNF production and lethality in a murine experimental endotoxin shock model was investigated. In some instances, serum IL-6 production was also evaluated. In this experimental model, C57BL/6 mice received 30 mg/kg LPS (E.

In vitro activation of murine peritoneal exudate cells (PEC) and peritoneal macrophages by ST 789.

ST 789 is a new synthetic compound characterized by an amino acidic group joined to the N9 position of the hypoxanthine ring, which has been shown recently to have immunomodulating properties and minimal toxicity. The drug has been reported to protect immunosuppressed mice from microbial infections and tumour growth, and to restore the mitogen-induced proliferation of splenocytes from immunosuppressed young mice. In this study, we show that in vitro addition of ST 789 is able to markedly augment the sheep red blood cells (SRBC) phagocytosis by PEC, and to potentiate the cytotoxic activity of peritoneal exudate (PE) macrophages (M phi) vs the L-M tumour cell line.

Immunorestorative properties of ST 789 on experimentally immunosuppressed and infected mice.

ST 789, a newly synthesized chemical characterized by an aminoacidic group joined to the N9 position of the hypoxanthine ring, has recently been shown to be endowed with immunomodulatory properties. In this study we tested ST 789 in vivo for protective effects in Cyclophosphamide-immunosuppressed CD1 mice experimentally infected with several bacterial and fungal pathogens. We found that immunosuppressed mice infected with either fungi or bacteria were significantly protected, as evaluated both by percent mortality and survival time, when treated with doses of ST 789 even as low as 0.

Modulation of splenic lymphocyte activities by a new hypoxanthine derivative (ST 789) in immunosuppressed mice.

Splenic lymphocytes of experimentally-immunosuppressed mice of different age (10 weeks and 6 months) were studied to evaluate their functional response following subcutaneous and intraperitoneal treatment with the hypoxanthine derivative N-alpha-5-(1,6-dihydro-6-oxo-9-purinyl)pentyloxy-carbonyl-L- arginine (ST 789). Experimental immunosuppression was carried out by injecting hybrid B6D2F1 mice with a single dose of cyclophosphamide (100 mg/kg, i.p.

Different in vitro response to rIL-1 beta of newborn and adult rat astroglia.

In recent literature, lymphokines have been reported to be able to promote both proliferation and maturation of some glial populations. In this paper, we compare the effect of rIL-1 on newborn and adult rat astroglial cells in vitro. In newborn, but not in adult astrocytes, 100 U/ml of rIL-1 beta increase [3H]thymidine incorporation with a maximal response by 3 days as compared to the control untreated culture.

Aging and immune response: a multivariate approach.

This study on the immune response was chosen as the experimental milieu for the aging process. Parameters associated with the immune response were measured in rats of different ages, thus providing multivariate conditions within which multidimensional data analysis procedures could be applied. These methods, specifically designed for analyzing complex situations, allowed for the delineation of some structural characteristics of maturity and senescence.

New potential immunoenhancing compounds. Synthesis and pharmacological evaluation of new long-chain 2-amido-2-deoxy-D-glucose derivatives.

A series of long-chain fatty acids and the corresponding 2-hydroxy, 2-oxo, 3-hydroxy acid glucosamides were evaluated as immunomodulating compounds. In a preliminary screening, 2-[(2-ethoxycarbonyloxy)tetradecanoylamino]-2-deoxy-D-glucos e (2b) and 2-(3-hydroxydodecanoylamino)-2-deoxy-D-glucose (5a) resulted to be the most effective in enhancing the glucosamine activity. The findings of in vitro-ex vivo tests (unidirectional mixed lymphocyte culture reaction and primary antibody production) and in vivo tests (delayed type hypersensitivity, protection against bacterial or fungal infection and against Sarcoma 180 or Lewis lung carcinoma transplants) were very encouraging and allowed to assume for the two substances a protective activity, presumably through the ability of activating phagocytic and NK cells.

Oxolinic acid--trimethoprim combination: effects on DNA synthesis and on viability of Escherichia coli.

The synergistic bactericidal effect of the oxolinic acid-trimethoprim combination has been confirmed on an exponentially growing strain of Escherichia coli, and is paralleled by a synergistic inhibition of 14C-uracil incorporation into the bacterial DNA. These data provide experimental support for the postulate that the synergistic effect of quinolone-trimethoprim combinations, observed both in vitro and in vivo, is due to a complementary blockade of bacterial DNA synthesis.

Controlled assessment of the concentrations of a new cephalosporin in bile and gallbladder.

The distribution of cephalexin in bile and in the gall bladder was investigated in humans after administering pivalexin--a new cephalexin derivative--that exhibits favourable pharmacokinetic characteristics versus cephalexin itself. Two groups of subjects were given either pivalexin or cephalexin in the form of capsules in a single oral dose. Pivalexin in view of its greater excretion of cephalexin in bile and its satisfactory fixation of cephalexin in the gallbladder, as compared with cephalexin itself, may reasonably be regarded as a recommendable antibiotic in the treatment of biliary-duct infections.

Semisynthetic beta-lactam antibiotics. III. Cephalosporin derivatives in the furyl series. Chemical and microbiological properties.

The synthesis of a series of 7-acylamido cephalosporins having a substituted furyl moiety in the side chain is described. These new cephalosporins were examined in vitro for antibacterial activity and evaluated for resistance to inactivation by beta-lactamases.

Semisynthetic beta-lactam antibiotics. II Cephalosporin derivatives in the naphthalene series. Chemical and microbiological properties.

A seris of new 7-acylamidocephalosporins, containing a substituted naphthalene moiety in the side chain, has been prepared and tested for their in vitro antibacterial activity. Some observations are made on the structure-activity relationships.

Synthesis of 7-acylamidodesacetoxycephalosporanic acids and corresponding pivaloyloxymethyl esters. Chemical and microbiological properties.

A series of 7-acylamidodesacetoxycephalosporanic acids and analogous pivaloyloxymethyl esters have been prepared and tested in vitro for antibacterial activity. Those acids which exhibited a significant in vitro activity, were also studied in vivo and compared with the corresponding esters. Experiments performed on laboratory animals showed that, after oral administration, the esters were absorbed more efficiently than the corresponding acids.

A new cephalosporin derivative (ST-21) orally administered in laboratory animals.

The pivaloxymethyl ester of 7-(D-2-amino-2-phenylacetamido)-desacetoxicephalosporanic acid hydrochloride (ST-21) and cephalexin possess the same bacteridal activity. In fact, in the animal body ST-21 releases cephalexin. The acute toxicity study shows the good tolerance of both substances, whereas the tissue distribution is different, both after oral and i.