Recombinant Escherichia coli-derived human interferon-gamma (rIFN-gamma) was given to a total of 20 patients by iv bolus injection at various doses once a week for 4 weeks. The sera obtained 7-10 days after the final injection were analyzed for antibodies against both rIFN-gamma and natural human IFN-gamma. Biological assays demonstrated that the postinoculation sera of the patients did not neutralize the antiviral activities of either rIFN-gamma or natural human IFN-gamma. Enzyme-linked immunosorbent assay showed that no detectable antibodies against rIFN-gamma were elicited. These results indicate that this rIFN-gamma preparation is not a potent antigen and may be suitable for longer-term clinical trials and applications in the future.

Animals↗

PubMed1985

Recombinant human interferons.

The genes for several human interferons (IFN) alpha, of IFN beta and IFN gamma have been cloned and expressed in bacterial cells. Recombinant interferons have been purified from these cells and shown to be as biologically active as their natural counterparts. The expression systems, purification schemes and the biochemical properties of these interferons are discussed.

Amino Acid Sequence↗

PubMed1985

[Animal experiment studies on the effect of unilateral tooth extraction on the growth of the skull and masticatory muscles. III. The masticatory muscles].

All continuous teeth were unilaterally extracted on the right side of the upper and lower jaws of 57 male and female Vietnamese belly pig. The animals were slaughtered 6, 7, 8, 9, 10, 11 and 12 after the extraction. Our investigations into quantitative changes in the masticatory musculature after unilateral extraction showed the dry weight of the musculature on the extraction side was reduced. This reduction was greatest in the case of the M. temporalis. The findings relating to the muscles are consistent with the results of the skull evaluations reported in the first 2 publications, with indicated that tooth extraction leads to only local changes in the jaw during postnatal development. The findings published in the 3 publications of this series relating to the bones and muscles are discussed.

Animals↗

PubMed1983

A new mass-spectrometric C-terminal sequencing technique finds a similarity between gamma-interferon and alpha 2-interferon and identifies a proteolytically clipped gamma-interferon that retains full antiviral activity.

A novel mass-spectrometric technique is described that permits the identification of the C-terminal peptide of a protein. The technique involves the incorporation of 18O into all alpha-carboxy groups liberated during enzyme-catalysed partial hydrolysis of the protein, followed by mass spectrometry to identify as the C-terminal peptide the only peptide that did not incorporate any 18O. The technique has been used to identify the true C-terminal tryptic peptide of a bacterially produced gamma-interferon and to distinguish it from a peptide produced by anomalous tryptic cleavage. It was found that a closely similar sequence segment of bacterially produced alpha 2-interferon undergoes an analogous cleavage. The technique was also used to identify the C-terminus of a clipped gamma-interferon that retains full antiviral activity.

Amino Acid Sequence↗

PubMed1982

Subtle but distinct impairments of rats with chemical lesions in the thalamic mediodorsal nucleus, tested in a radial arm maze.

The performance of rats trained in a radial arm maze was tested before and after chemical lesions of the thalamic mediodorsal nucleus or the ventral tegmental area. Their behavior was compared with that of a sham-operated control group. Lesions were produced with ibotenic acid, a compound that selectively destroys neurons while apparently leaving fibers of passage intact. Results revealed no intergroup difference in the number of errors performed when all six trials were given in one session without interruption. The group with mediodorsal lesions made, however, significantly more errors than either of the other two groups when a delay of 1 hr was interposed between the first four and the last two trials. Furthermore, these rats differed from rats of the other groups in the number of sessions necessary to reach criterion, in the time needed to finish a session, and in the directness with which a goal was approached. Rats with lesions of the ventral tegmental area did not differ from rats of the sham-operated control group in any of the measures taken. It is suggested that the deficits of rats with mediodorsal lesions resemble qualitatively those found in human patients with lesions of the mediodorsal nucleus.

Animals↗

PubMed1982

Subclasses of simian-virus-40 large tumor antigen. Partial purification and DNA-binding properties of two subclasses of tumor antigen from productively infected cells.

Two major subclasses of simian virus 40 tumor antigen were prepared from productively infected monkey cells. These subclasses can be distinguished by their sedimentation properties: one tumor antigen form sediments at 5-6S and the other at 14-16S. The DNA-binding properties of these subclasses were investigated by two different experimental procedures. In the first procedure, the DNA binding of subclasses of crude tumor antigen, separated by zone velocity sedimentation, were assayed by immunoprecipitation of the DNA-protein complexes. In the second procedure, the two tumor antigen forms were partially purified by column chromatography and DNA binding was tested in a filter binding assay. Both procedures gave comparable results. (a) The 5-6-S and the 14-16-S tumor antigen bound specifically to a DNA restriction fragment containing the viral genome control regions. (b) At low salt concentrations, both subclasses bound to specific and to nonspecific DNA sequences; competition experiments in the presence of nonspecific DNA showed, however, that the affinity of both tumor antigen forms for the viral genome control region was at least 10-fold higher than their affinity for nonspecific DNA sequences. (c) The binding of the 5-6-S subclass to viral control region DNA was optimal at 60-80 mM NaCl while specific DNA binding of the 14-16-S form was optimal at 150-200 mM NaCl; however, binding of the 14-16-S form to nonspecific DNA sequences was also more resistant to high salt concentrations than that of the 5-6S form. (d) Both tumor antigen forms bound well to specific and to nonspecific DNA at pH 6-6.5; with increasing pH values, binding to nonspecific DNA decreased while binding to specific DNA reached an optimum at pH 7-7.5. Binding of the 14-16-S form to viral origin DNA was more resistant to pH values above 7.5 than binding of the 5-6-S form.

Animals↗

PubMed1981

Replication of SV40 chromatin in extracts from eggs of Xenopus laevis.

Simian virus 40 (SV40) nucleoprotein complexes were prepared from lytically infected cells and used as primer-templates for DNA replication in protein extracts from Xenopus eggs. We found that nucleoprotein containing replicating SV40 DNA served as primer-template while nucleoprotein with nonreplicating SV40 DNA was ineffective. In vitro DNA synthesis begins with short DNA fragments ("Okazaki fragments") which are, in later steps, joined to give unit length SV40 DNA strands, suggesting that in vivo initiated rounds of replication are completed in vitro in the Xenopus system. This conclusion is supported by a restriction enzyme analysis showing that in vitro DNA synthesis occurs in fragments distal to the SV40 origin of replication. Our studies indicate that SV40 DNA replication in Xenopus extracts can be used an an experimental system to study the biochemistry of replicative DNA chain elongation in vitro.

Animals↗

PubMed1981

[Vivisection studies on the effects of unilateral tooth extraction on growth of the skull amd masticatory musculature (author's transl)].

Following up on the 1st part of this cycle of publications, the 2nd Bulletin deals with investigations on upper and lower jaw growth in the Vietnamese belly pig after extracting all teeth as they appeared in the right half of the jaw. The results showed characteristic changes on the side of the extraction compared with the skull on the other side. They also show clearly that the effects of unilateral loss of teeth on the development of the bony part of the chewing apparatus are very local. This is made evident by analysis distances measured for the 3rd and 4th upper jaw widths and the 2nd vertical height of the bottom jaw. In contrast to other authors, we found no changes in the longitudinal and lateral development of the bottom jaw. Due to the slight degree of development of the alveolar process of the bottom jaw in the region of the 1st permanent molar, a significant reduction in surface area was found when removing the 2nd molars, which was performed usually at an early point, only in the group slaughtered after 12 months.

Animals↗

PubMed1980

Maturation of newly replicated chromatin of simian virus 40 and its host cell.

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Chromatin↗

PubMed1980

Replication of simian virus 40 chromatin in vitro depends on the amount of DNA polymerase alpha associated with replicating chromatin.

Replication of simian virus 40 (SV40) chromatin in vitro is inhibited by chloride but stimulated by acetate anions even at physiological concentrations of 100-200 mM. In a similar fashion DNA polymerase alpha is affected with respect to the activity with activated DNA as primer template. Furthermore, at concentrations of 100-200 mM acetate DNA polymerase alpha remains associated with replicating chromatin, whereas association is strongly reduced when chloride anions are used at the corresponding concentrations. Thus the salt behaviour of DNA polymerase alpha explains the salt sensitivity of the replication system. Our results confirm the importance of this enzyme for DNA replication.

Animals↗

PubMed1980

A histone-specific acetyltransferase is associated with simian-virus-40 chromatin.

[14C]Thymidine-labeled simian virus 40 nucleoprotein complexes were prepared from nuclei of lytically infected African green monkey kidney cells. The nucleoprotein complexes were further purified by sucrose gradient centrifugation and then incubated in the presence of [3H]acetyl-coenzyme A. We observed a transfer of [3H]acetyl groups to the endogenous histones H2B, H3 and H4. The enzyme was solubilized in the presence of 0.5 M NaCl and showed properties described for the DNA-binding acetyltransferase (J. Böhm, E. J. Schlaeger and R. Knippers, preceding paper in this journal).

Acetylation↗

PubMed1980

An analysis of the relation between dysphonia in shipyard workers and working in noise.

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Adult↗

PubMed1980

[Vivisection studies on the effects of unilateral tooth extraction on growth of the skull and masticatory musculature. I. Overall skull, orbita, zygomatic arch, rear skull (author's transl)].

Skull growth is affected by numerous factors, including dentition. Animal experiments have assumed considerable importance in connection with such studies. This series of publications deals with the response of the skull skeleton and masticatory muscles to extraction of each emerging tooth in the right half of the jaws of Vietnamese belly pigs. The animals were slaughtered at various ages ranging from 6 to 12 months, throughout an important phase of post-natal skull development. Biomathematical methods were used to analyse the macerated skull and the masticatory musculature. Linear differential equations have proved useful for describing growth processes. The 1st report deals with the distances measured for the overall and rear skull, the orbita and the zygomatic arch. Differences between the right and left sides are slight with respect to these distances. Significant differences were found only in the range of the front part of the zygomatic arch during the 6th, 7th, 8th, 11th and 12th month of life.

Animals↗