Multichannel recording of tibial-nerve somatosensory evoked potentials.

Study Aims: The topography of the peaks of tibial-nerve somatosensory evoked potential (SEP) varies among healthy subjects, most likely because of differences in position and orientation of their cortical generator(s). Therefore, amplitude estimation with a standard one- or two-channel derivation is likely to be inaccurate and might partly cause the low sensitivity of SEP amplitude to pathological changes. In this study, we investigate whether 128-channel tibial-nerve SEP recordings can improve amplitude estimation and reduce the coefficient of variation.

Purification of a glutathione S-transferase and a glutathione conjugate-specific dehydrogenase involved in isoprene metabolism in Rhodococcus sp. strain AD45.

A glutathione S-transferase (GST) with activity toward 1, 2-epoxy-2-methyl-3-butene (isoprene monoxide) and cis-1, 2-dichloroepoxyethane was purified from the isoprene-utilizing bacterium Rhodococcus sp. strain AD45. The homodimeric enzyme (two subunits of 27 kDa each) catalyzed the glutathione (GSH)-dependent ring opening of various epoxides.

Electron-dense granules in Desulfovibrio gigas do not consist of inorganic triphosphate but of a glucose pentakis(diphosphate).

Under certain growth conditions the sulfate-reducing bacterium Desulfovibrio gigas forms electron-dense granules in the cells which had been claimed to consist of a magnesium triphosphate). We observed granules after cultivation in media with a low Fe2+ or NH4+ concentration and reinvestigated the nature of the electron-dense bodies. Energy-dispersive X-ray analysis of the granules in the cells showed that they contain large amounts of P, Mg, and K.

Synthesis and identification of twelve A-ring reduced 6 alpha- and 6 beta-hydroxylated compounds derived from 11-deoxycortisol, corticosterone and 11-dehydrocorticosterone.

The synthesis and identification of 12 A-ring reduced 6 alpha-(and 6 beta-)hydroxylated compounds derived from 11-deoxycortisol (S), corticosterone (B) and 11-dehydrocorticosterone (A) are reported here. These steroids were prepared in two steps from the corresponding 6 6 alpha-(and 6 beta-)hydroxy-4-pregnene-3-ones. Selective reduction of the 4,5 double bond yielded 12 6 alpha-(and 6 beta)hydroxy-5 alpha-(and 5 beta)pregnane-3,20-diones.

Low molecular weight proteins as carriers for renal drug targeting. Preparation of drug-protein conjugates and drug-spacer derivatives and their catabolism in renal cortex homogenates and lysosomal lysates.

Low molecular weight proteins (LMWPs) are known to be reabsorbed and catabolized primarily by the proximal tubular cells of the kidneys. As such, LMWPs might serve as drug carriers that release drugs site-specifically in the kidney. We tested this concept in vitro by coupling different drugs to the LMWP lysozyme both directly (amide bond) and via different spacers: oligopeptides (amide bond), (poly-)alpha-hydroxy acids (ester bond), and a pH sensitive cis-aconityl spacer (amide bond).

31phospho-NMR demonstration of phosphocysteine as a catalytic intermediate on the Escherichia coli phosphotransferase system EIIMtl.

The mannitol-specific phosphotransferase system transport protein, Enzyme IIMtl, contains two catalytically important phosphorylated amino acid residues, both present on the cytoplasmic part of the enzyme. Recently, this portion has been subcloned, purified, and shown to be an enzymatically active domain. The N-terminal half has also been subcloned and shown to be the mannitol-binding domain.

Abnormal urinary bile acids in a patient suffering from cerebrotendinous xanthomatosis during oral administration of ursodeoxycholic acid.

The urinary bile acid profile, obtained by capillary gas chromatography, of a patient suffering from cerebrotendinous xanthomatosis and treated with ursodeoxycholic acid demonstrated, besides the occurrence of 23-norcholic acid and (23R)-hydroxycholic acid (as a consequence of this disease), six additional unknown bile acids and three known bile acids, viz. ursodeoxycholic acid, hyocholic acid and omega-muricholic acid. The structure of two of the unknown bile acids were elucidated and proven by organic syntheses.

Thymus independence of eosinophilia induced by a non-parasite antigen.

Eosinophilia is primarily a T-cell-dependent phenomenon, related to helminthic infections. Using a rat model (+/rnu), it has been shown that keyhole limpet hemocyanin (KLH) in complete Freund's adjuvant (CFA) induced blood eosinophilia, but only after pretreatment with cyclophosphamide (CY). CY alone caused an eosinophilopenia which was reversed by CFA or KLH-CFA treatment.

T-cell involvement in adoptive transfer of line 10 tumor immunity in strain 2 guinea pigs.

Several aspects of adoptive transfer of tumor immunity were studied in the line 10 hepatocarcinoma in the syngeneic Sewall-Wright strain 2 guinea pig. In particular, the need for cooperation between donor and recipient T-cells was investigated. Donor immune spleen cells remained immunologically capable of inducing tumor rejection for at least 160 days after adoptive transfer.

Selective localization of tumor-immune spleen cells at the tumor challenge site after adoptive transfer of line 10 tumor immunity in strain 2 guinea pigs.

In this study, the distribution of immune spleen cells was investigated after adoptive transfer of immunity in inbred strain 2 guinea pigs. Spleen cells obtained from line 10 immune donor animals became specifically restimulated in vitro with 3 M KCl-extracted line 10 soluble proteins, but not with 3 M KCl-extracted line 1 or liver proteins. After 4 days culture in vitro, these specifically restimulated immune spleen cells retained their antitumor activity in vivo after adoptive transfer.

Toxicity of bis(tri-n-butyltin)oxide in the rat. II. Suppression of thymus-dependent immune responses and of parameters of nonspecific resistance after short-term exposure.

To evaluate the functional significance of bis(tri-n-butyltin)oxide (TBTO)-induced thymus atrophy, lymphocyte depletion in spleen and lymph nodes, lymphopenia, and increased serum IgM and decreased IgG concentrations, in vivo and in vitro function studies were performed for specific and nonspecific resistance. Weaned male rats were fed diets containing 0, 20, or 80 mg TBTO/kg for at least 6 weeks. Regarding the thymus-dependent immunity, delayed-type hypersensitivity reactions to ovalbumin as well as tuberculin were significantly depressed at both dietary concentrations.

Effect of triphenyltin hydroxide on the immune system of the rat.

To evaluate the functional significance of triphenyltin hydroxide (TPTH)-induced lymphopenia and lymphocyte depletion in thymus-dependent areas of spleen and lymph nodes, various immune function studies were carried out after 3 or 4 weeks TPTH exposure. Weaned male rats were fed a diet containing 25 mg TPTH/kg, a concentration that did not influence food intake and weight gain. TBTO exposure was continued during the course of the function tests.

Experimental screening of BCG preparations produced for cancer immunotherapy: safety and immunostimulating and antitumor activity of four consecutively produced batches.

Four consecutively produced batches of Bacillus Calmette-Guérin (BCG) especially intended to be used for cancer immunotherapy were investigated for consistency of the vaccine. Each batch was investigated directly after production of the vaccine, so that the four batches were not tested simultaneously. The activity of the four batches was investigated in general safety assays, immunostimulation assays, and two different tumor models.

Antitumor activity, induction of cross-resistance, and nephrotoxicity of a new platinum analogue, cis-1,1-diaminomethylcyclohexaneplatinum(II) sulfate, and of cis-diamminedichloroplatinum(II) in an immunocytoma model in the LOU/M rat.

A newly synthesized platinum analogue, cis-1,1-diaminomethylcyclohexaneplatinum(II) sulfate (TNO-6), was compared with cis-diamminedichloroplatinum(II) (cis-DDP) for antitumor activity and nephrotoxicity. Antitumor activity was determined in an IgM immunocytoma model in the LOU/M rat. Tumor cells were inoculated on the left flank, and therapy was started when a tumor diameter of 10 to 30 mm was reached.

The athymic nude rat. IV. Immunocytochemical study to detect T-cells, and immunological and histopathological reactions against Trichinella spiralis.

The anti-parasite response was investigated after oral infection of athymic nude (rnu/rnu) rats and heterozygous (+/rnu) littermates with 1000 muscle larvae of Trichinella spiralis. No IgM, IgG and IgE antibodies were detected in serum of rnu/rnu rats. Expulsion of adult worms from the small intestine was prolonged (worms were nearly all expelled at days 14 and 91 in +/rnu and rnu/rnu rats respectively).

Immunotherapy by intralesional injection of BCG cell walls or live BCG in bovine ocular squamous cell carcinoma: a preliminary report.

Cows of the Dutch Frisian and Maas-Rijn-IJssel breed with histologically confirmed ocular squamous cell carcinoma showed complete regression of the primary tumor in 70 or 60% of the cases after intralesional injection of a BCG cell wall or live BCG vaccine, respectively. Recurrence of the tumor was observed in 57% of the animals treated with BCG cell walls and in 25% of the animals treated with live BCG vaccine. Spontaneous regression was seen in 20% of the untreated cows.

Regression of induced keratoacanthomas in anagen (hair growth phase) skin grafts in mice.

Transplants of experimental keratoacanthomas induced in skin grafts which were in the growth phase of the hair follicle cycle (anagen phase) were carried out in immunocompetent and immunoincompetent receipients ("nude" mouse, nu/nu). No differences in gross graft observations were noticed. More than 80% of all keratoacanthomas disappeared postgrafting.

Lack of effect of Spironucleus (Hexamita) muris on the immune response to tetanus toxoid in the rat.

In contrast to the mouse, in rats the immune response to tetanus toxoid was not altered by infection with Spironucleus muris.

Hexachlorobenzene-induced stimulation of the humoral immune response in rats.

Rats were fed diets containing 0, 500, 1000, and 2000 mg HCB/kg during a 3-week period. Marked weight increases of spleen, popliteal and mesenteric lymph nodes and of the liver were found. Histologically, the white pulp in the spleen was enlarged because of an increase in size of marginal zones and follicles.