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M Alt

Publications and source records attributed to M Alt.

At least 37 records · Page 2Linked to original sources
PubMed1995

Specific inhibition of hepatitis C viral gene expression by antisense phosphorothioate oligodeoxynucleotides.

The inhibitory effect of antisense phosphorothioate oligodeoxynucleotides (S-ODN) on hepatitis C viral gene expression and analyzed in an in vitro test system and in cell culture. S-ODN were directed against different stem loop structures in the 5'noncoding region (NCR) of the hepatitis C virus, (HCV) RNA and against a nucleotide stretch, including the start codon of the polyprotein precursor. The inhibitory effect of these S-ODN was quantified employing a viral RNA consisting of the first 407 nucleotides of a HCV type 1b genome fused to the coding sequence of the firefly luciferase gene. For in vitro assays this RNA was generated by in vitro transcription and used as a template in a rabbit reticulocyte lysate in vitro translation system. The production of active luciferase in the absence or presence of S-ODN was monitored using an enzymatic assay. The best results were obtained with S-ODN 4 directed against nucleotides 326 to 348, comprising the start AUG of the polyprotein coding sequence. With this oligonucleotide, a specific and dose-dependent effect was observed with a maximal inhibition of 96 +/- 1% at a S-ODN concentration of 4.14 mumol/L. For cell culture experiments, the hepatoblastoma cell line HepG2 was transfected with a plasmid expressing the HCV-luciferase fusion RNA. In this assay system S-ODN 2, complementary to nucleotides 264 to 282 of the HCV RNA, and S-ODN 4 were most efficient and reduced the viral translation by 96 +/- 0.4% and 94 +/- 0.7%, respectively, at a concentration of 0.3 mumol/L. The inhibition was specific (1) because the expression of the HCV-luciferase fusion RNA was not significantly impaired by the control S-ODN and (2) because the expression of an unrelated messenger RNA was not or only slightly downregulated. These data suggest that HCV gene expression can be inhibited effectively by antisense S-ODN. Therefore, this approach represents a promising perspective for the treatment of hepatitis C.

Base Sequence↗
PubMed1995

[Are nasal swabs for swine appropriate for the diagnosis of bacterial pneumonia agents?].

Nasal swabs and lungs of 150 pigs with pneumonia were tested by culture at post mortem examination. The isolated agents were Pasteurella multocida (P.m.), P. haemolytica, Bordetella bronchiseptica, Actinobacillus pleuropneumoniae, Staphylococcus aureus, Streptococcus spp. and Escherichia coli. P.m. was most frequently found, and this agent only showed a significant correlation between lungs and nasal swabs. In 80.6% of pigs with P.m. in the lung the agent was detected in the nose, too. Drug resistance patterns of P.m. isolates from lungs and noses of the single animals were identical or similar, also in case of different capsular types. The examination of porcine nasal swabs for bacteria capable of causing pneumonia should be limited to P. multocida. Demonstration of agents in lung material is generally more certain.

Animals↗
PubMed1993

The pharmacokinetics of thiamphenicol in lactating cows.

The pharmacokinetics of thiamphenicol were studied after intravenous and intramuscular administration of 25 mg/kg body weight in lactating cows. Distribution (t1/2 alpha) and elimination (t1/2 beta) half-lives of 6.10 +/- 1.39 min and 1.60 +/- 0.30 h, respectively, were obtained after intravenous administration. The body clearance was 3.9 +/- 0.077 ml/kg per min and the apparent volume of distribution was 1220.79 +/- 256.67 ml/kg. The rate at which thiamphenicol appeared in the milk, as indicated by the penetration half-life (t1/2P) (serum to quarters), was found to be 36.89 +/- 11.14 min. The equivalent elimination half-life (t1/2E) (quarters to serum) from the milk was 3.62 +/- 1.06 h and the peak thiamphenicol concentration in the milk was 23.09 +/- 3.42 micrograms/ml at 2.5 +/- 0.32 h. After intramuscular injection, the elimination half-life was 2.2 +/- 0.40 h, the absorption half-life was 4.02 +/- 1.72 min and the peak concentration in the serum was 30.90 +/- 5.24 micrograms/ml at 23 +/- 8.4 min. The bioavailability after intramuscular administration approached 100%. The penetration half-life was 50.59 +/- 6.87 min, the elimination half-life was 5.91 +/- 4.97 h and the mean peak concentration in the milk was 17.37 +/- 2.20 micrograms/ml at 3.4 +/- 0.22 h.

Animals↗
PubMed1993

Resistance of human fibroblasts to c-fos mediated transformation.

Overexpression of the proto-oncogene c-fos induces transformation of primary avian and established rodent mesenchymal cells and tumor development in transgenic mice. As overexpression of Fos was also found in several human tumors of mesenchymal origin, we were interested whether c-fos is a transforming protein for human cells. Since fos genes transduced by infection competent vectors were most efficient in cellular transformation, expression cassettes of the human c-fos were introduced into a replication competent herpesvirus saimiri vector. Infection of human neonatal fibroblasts, cells of mesenchymal origin, resulted in episomal persistence of the recombinant viral genome and expression of c-fos in high excess. However careful examination for transformed phenotype failed to detect any changes in morphology, serum dependence, anchorage dependence, and life span, suggesting resistance of human mesenchymal cells against c-fos mediated transformation.

Animals↗
PubMed1993

[Comparison of EBL cells and ELISA in the culture and serological diagnosis of rhinitis atrophicans in swine].

Pasteurella multocida isolates from 271 nasal swabs of pigs were tested in EBL cell culture for toxin production. Mixed bacteria cultures of the same swabs were examined in the P. multocida toxin ELISA K462 (Dakopatts). In the ELISA 114 swabs reacted positive, whereas toxigenic P. multocida were detected by the EBL cell test in 86 swabs. In a neutralization test (SNT) combined with EBL cell culture and with the ELISA 111 sera were examined for P. multocida antitoxin. The toxin had to be more concentrated for the ELISA than for the cell culture; therefore the SNT with EBL cells was more sensitive. Whereas 101 sera had titres of 1:4 or higher in the cell culture, 68 of these sera were positive in the ELISA.

Animals↗
PubMed1992

Role of human T-cell leukemia virus type 1 X region proteins in immortalization of primary human lymphocytes in culture.

Human T-cell leukemia virus type 1 (HTLV-1) immortalizes human CD4+ T lymphocytes in culture. Previous studies show that in the context of a herpesvirus saimiri vector, the sequence of the X region at the 3' end of the HTLV-1 genome is also capable of immortalizing CD4+ lymphocytes in the absence of HTLV-1 structural proteins. The X region of HTLV-1 encodes two trans-acting viral proteins, the 42-kDa Tax protein and the 27-kDa Rex protein. Infection of human cord blood cells with herpesvirus saimiri recombinants which contain HTLV-1 X region sequences defective for expression of tax, rex, or both tax and rex demonstrates that tax function is necessary and sufficient for immortalization of primary human CD4+ cord blood lymphocytes in culture in the context of the herpesvirus saimiri vector.

Base Sequence↗
PubMed1991

A pair of selectable herpesvirus vectors for simultaneous gene expression in human lymphoid cells.

The genome of Herpesvirus saimiri, a lymphotropic virus of non-human primates, was used to develop a vector system for transducing foreign genes into primary human T-cells and T-lymphoid cell lines. Recombinant viruses were obtained by homologous recombination of the viral genome with linearized plasmid DNA. The plasmid used contained a fragment of virion DNA, a hygromycin-B-resistance marker (HyR), and a multiple cloning site for the insertion of additional expression cassettes. The resulting recombinants were efficiently enriched and were plaque-purified. The virus mediating HyR and a H. saimiri strain carrying the Geneticin-resistance marker were used to infect the human T-lymphoid cell line Jurkat. Lymphocytes with a double-resistant phenotype were shown to contain the two different H. saimiri recombinants persisting as episomes at high multiplicity. The H. saimiri vector system will be suitable to study cooperating regulatory genes in T-lymphocytes.

Base Sequence↗
PubMed1991

Persistence of selectable herpesvirus saimiri in various human haematopoietic and epithelial cell lines.

Herpesvirus (h.) saimiri, an infectious agent of squirrel monkeys, is capable of persisting in T lymphocytes of various primate species. It has been used as a vector for the functional analysis of regulatory genes in primary human T lymphocytes. As it is not yet known whether other cell types are capable of supporting viral persistence, various human cell lines were investigated using selectable h. saimiri recombinants. The lines chosen represent cells from the epithelium and connective tissue as well as from all haematopoietic lineages, i.e. cells of B and T lymphoid origin as well as myeloid-, fibroblast- and carcinoma-derived cultures converted to Geneticin or hygromycin B resistance, and harbouring episomal DNA of the selectable recombinants. The Burkitt's lymphoma-derived cell line Raji also contained simultaneously persisting episomes of the Epstein-Barr virus. Most of the cell cultures except a pancreatic carcinoma line and foreskin fibroblasts did not produce infectious virus. These observations show that a herpesvirus genome can persist episomally in a broad range of cultured cell types. The variety of infectable cell types and species suggests the presence of a widely distributed and well conserved virus receptor for h. saimiri. Thus the h. saimiri genome could be applied more generally as a vector.

Blotting, Northern↗
PubMed1989

[The appearance of ovarian cysts in young sows after treatment with gonadotropin preparations for estrus induction].

In 72 (46%) of 155 gilts discarded for genetic reasons after performance testing and housed under fattening conditions no heat could have been detected during the first 30 days. The gilts were assigned alternatingly to a control group and four different treatments of delayed puberty. The induction of puberty was carried out by injections of 1000 iu PMSG, 400 iu HCG and 2 mg oestradiol benzoate, 400 iu PMSG and 200 iu HCG and 800 iu PMSG and 400 iu HCG. If there was no estrus gilts were slaughtered 12 days later for examination of the ovaries. Those coming into estrus were slaughtered 8 days after disappearance of estrus. Estrus could be induced in 69 to 94% of the gilts, whereas 40% of the untreated showed estrus signs. After treatment with PMSG and HCG in 40 and 87% of the gilts cysts were found whereas none of the untreated and 26 and 29% of those treated with PMSG und HCG + oestradiol benzoate revealed ovarian cysts. In addition, those gilts that had come into estrus during the first 30 days were given injections of either 1000 iu PMSG or 800 iu PMSG and 400 iu HCG. The injections were made either on the 5th, 10th or 15th day of cycle. In both latter groups significantly more gilts showed standing heat than after treatment at cycle day 5. The results of inspection of the ovaries at slaughter and steroid hormones could not be assigned to a defined stage of the physiological ovarian cycle.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1989

[Diagnosis of fertility disorders of the sow by the determination of estradiol and progesterone in the blood serum].

Serum samples of 181 selected sows had been taken the day before culling, reproductive tracts were examined and the culling reasons were recorded. In sows with histories of multiple returns cyclic ovaries were found predominantly. All of the few sows culled for prolonged behavioural oestruses suffered from ovarian cysts. 87% of the sows whose serum oestradiol level exceeded 10 pmol/l and whose serum progesterone level exceeded 2.5 pmol/l revealed ovarian cysts. In 72% of the sows whose hormone concentrations were below these levels inactive ovaries were found. Corpora lutea, partly in association with ovarian cysts were present in 91.1% of the sows whose sera exhibited progesterone levels greater than 2.5 nmol/l and concentrations of oestradiol less than 10 pmol/l. As a rule ovarian diagnoses by combined determination of oestradiol and progesterone could be confirmed by the results of morphological examination of the reproductive tracts. In practice after selection of sows suffering from fertility disorders an even better reliability in diagnosis of ovarian disorders may be achieved than in this investigation.

Animals↗
PubMedDate not supplied

[Hyperthyroidism and immune hemolytic anemia following amiodarone therapy].

We report the cases of two patients who, after prolonged amiodarone therapy developed hyperthyroidism and immune haemolytic anaemia. Antibodies were of the IgG type and non-specific at elution. A search for other causes of haemolytic anaemia with positive Coombs' test gave negative results. Antiamiodarone antibodies have recently been discovered; they reflect an immunological disturbance due to this drug and might be responsible for some of the undersirable effects of amiodarone. In our patients, hyperthyroidism and haemolytic anaemia were induced by a dual mechanism: accumulation of amiodarone and induction of an effect of this drug on the immune system.

Aged↗
PubMedDate not supplied

Anaphylactic reactions after therapeutic injection of mistletoe (Viscum album L.).

Mistletoe (Viscum album) is a plant that is semiparasitic of several trees: apple, oak, pine trees, etc. Because of the probable cytolytic action of one of the leaf's most abundant composites, in some countries mistletoe is used as a complementary medicine. Although only a few adverse reactions have been noted (cephalea, fever), cases of anaphylactic shock have been described. We present three cases of severe reaction after injection of mistletoe extract. Two of the patients had cancer. The third, whose brother had cancer, used the plant for preventive purposes. We discuss the danger of possible severe reactions due to the use of products employed in so-called alternative therapies.

Adenocarcinoma↗