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B Matz

Publications and source records attributed to B Matz.

48 records · Page 3Linked to original sources
PubMed1983

Effects of nicotine on stimulus sensitivity and response bias in a visual vigilance task.

Signal detection analysis was used to examine the effects of nicotine on a visual vigilance task. Groups of light, heavy and non-smokers performed the 80-min task on three separate occasions, and received different doses of nicotine each time. For all three types of smoker, nicotine significantly counteracted the decrement in stimulus sensitivity which occurred over time in the placebo condition, while having no effect on response bias. We argue that nicotine produced this effect by acting on the central, cholinergic pathways controlling electrocortical arousal, and therefore that these pathways play a role in the control of human information processing.

Arousal↗
PubMed1982

Electromyographic findings in various forms of progressive systemic sclerosis.

Electromyographic findings were studied in 32 women and 7 men with progressive systemic sclerosis. Among the 14 patients in group 1, 7 had the CREST syndrome in an early stage while the 14 patients in group 2 had advanced CREST-type lesions. The 18 patients in group 3 had diffuse scleroderma with extensive visceral involvement. In all groups, the mean duration of single potentials was reduced and the percent of polyphasic potentials was above normal in groups 2 and 3. Distal muscles were more involved in group 1, and proximal muscles in group 2. In group 3, involvement of various muscles was nearly equal. Electromyographic changes correlated with the clinical condition of the patients. Overall, the findings in this study are similar to findings from other laboratories.

Action Potentials↗
PubMed1982

Analysis of Mycoplasma hyorhinis genome by use of restriction endonucleases and by electron microscopy.

The chromosome of Mycoplasma hyorhinis was analyzed by using different restriction endonucleases and electron microscopy. It was found that restriction enzymes BstEII, XhoI, and SacI are the enzymes of choice for analysis and characterization of M. hyorhinis. The bands resulting from digestion of M. hyorhinis DNA with BstEII had apparent molecular weights ranging from 1.2 X 10(6) to 75 X 10(6). The apparent total molecular weight of DNA was calculated from the molecular weights of the individual bands and found to be 251 X 10(6). Electron microscopic contour length measurements of the largest DNA fragments verified the molecular weight values calculated from gel analysis. Electron microscopic contour length measurements of intact DNA of M. hyorhinis revealed a molecular weight of 5.4 +/- 5 X 10(8). The discrepancy between the values of molecular weight of M. hyorhinis DNA as determined by restriction enzyme analysis and contour length measurement is based on the fact that some of the DNA fragments which migrate as an apparent single band in the agarose gel really are double or multiple DNA fragments.

Base Sequence↗
PubMed1981

The plaque-forming factor for mink lung cells present in cytomegalovirus and herpes-zoster virus stocks identified as Mycoplasma hyorhinis.

Previous investigation of the ability of cytomegalovirus and varicella-zoster virus to replicate in a variety of cell lines suggested that both virus types plaqued with high efficiency in mink lung cells. However, many of the virus isolates used appeared to be contaminated with mycoplasma. We now report that the observed cytopathic effect is due to a mycoplasma which grows lytically to high titre in mink lung cells, but is difficult to cultivate in cell-free media. The mycoplasma was plaque-purified and shown to contain DNA with a buoyant density of 1.684 g/ml, with restriction endonuclease patterns identical to the porcine mycoplasma M. hyorhinis. This was confirmed by serological identification.

Animals↗
PubMed1980

Experimental infection and the state of viral latency of adult tupaia with herpes simplex virus type 1 and 2 and infection of juvenile Tupaia with temperature-sensitive mutants of HSV Type 2.

The susceptibility of adult Tupaia Belangeri to infection with herpes simplex virus (HVS) was investigated. Adult animals were inoculated intraperitoneally with HSV type 1 or 2. With the exception of HSV-2, strain HG-52, 10(5)--10(6) PFU of all HSV strains caused lethal infection irrespective of the age of the animals. Infections HSV was recovered from the spinal cord of those animals which had survived infection with a low dose of virus. The DNA of the recovered viruses was compared to the DNA of the inoculated HSV. The viral genome of the recovered HSV was unchanged as judged by analysis of the fragment pattern of the viral DNA's using restriction endonucleases. Animals which had survived the first HSV infection were protected against a second infection even at highly lethal doses of HSV-1 or 2. Juvenile Tupaia survived infection with temperature-sensitive mutants of HSV-2, strain HG-52, which induced protection against a second infection with lethal doses of HSV-1 or 2.

Aging↗
PubMed1980

Physical map of tupaia adenovirus DNA by cleavage with restriction endonucleases and partial denaturation.

The double-stranded DNA of an adenovirus of tupaia (TAV) which has a mol. wt. of 21.5 X 10(6) was analysed as follows: the cleavage sites of restriction endonucleases BamHI, EcoRI, KpnI, SmaI, BstEII, ClaI and HpaI were determined by complete, partial and double digestion followed by gel electrophoretic separation of the resulting fragments. Terminal HpaI fragments were determined by hydrolysing the intact DNA with exonuclease III before restriction enzyme cleavage. Partial denaturation mapping of uncleaved DNA and EcoRI fragments revealed the cleavage sites of EcoRI as well as A + T-rich regions at both termini of the genome.

Adenoviridae↗
PubMed1978

Establishment of a variant cell clone growing at 41 degrees C from embryonic rat and tupaia (tree shrew) fibroblast cells.

Rat and tupaia 41 degrees C temperature variant cell clones were derived from parental embryonic cells, cloned and established in tissue cultures. Both variant cell clones grew permanently at 41 degrees C. The morphology of these cell clones was altered in comparison to the original fibroblast cell clones. The cell biological characterization of the rat and tupaia 41 degrees C temperature variant cell clones showed that both cell clones were stable. After abolishing the selection pressure (incubation at 41 degrees C) for more than 10 further cell passages by incubation at 37 degrees C and then raising the temperature again to 41 degrees C, neither of the cell clones lost their newly acquired property of growing at 41 degrees C. This fact demonstrates that the newly acquired property is certain to be genetically manifest in both cell clones. The modal number of chromosomes of the rat 41 degrees C temperature variant cell clone was increased, and in the case of the tupaia variant cell clone, bimodality was observed. The plating efficiency of both cell clones did not rise significantly in comparison to the parental cells. Neither of the 41 degrees C temperature variant cell clones grew in semi-solid medium.

Animals↗
PubMed1977

[Evaluation of electromyographic recordings in the detection of Duchenne's dystrophy carriers].

The purpose of this work was to compare the possibility of detecting subtle changes in muscular bioelectric activity which are observed in some carriers of Duchenne dystrophy gene using two methods: routine quantitative electromyography and automatic EMG recording (with ANOPS computer). Twenty-one confirmed dystrophy-gene carriers were examined Two muscles were studied in each case: m. biceps brachii and m. quadriceps femoris. There was no difference between the detectability of reduced potential durathion with both methods, but automatic recording made possible a much more accurate determination of the percent of polyphasic potentials. For example, using automatic recording 16.5% of polyphasic potentials were found in the quadriceps femoris muscle of carriers and 15.3% in the biceps brachii muscle, while in routine electromyography these values were respectively 9.9% and 8.9%. This parameter is particularly useful for recognition of very early and slight pathological processes--because of that automatic EMC recording seems to be superior to routine quantitative EMG in the detection of Duchenne dystrophy carriers in whom only very small changes may be expected. In the investigations carried out as yet the authors observed that the introduction of automatic EMG recording raised the detectability rate of gene carriers by 18.9% in relation to the rate of detection by means of CPK determination (previously the EMG raised this rate only by 5 to 9%).

Adult↗
PubMedDate not supplied

Recurrent herpetic keratitis during topical acyclovir application.

Dendritic herpetic keratitis developed in a 49-year-old patient during topical acyclovir treatment. A positive herpes simplex culture was obtained. After acyclovir was replaced by trifluorothymidine and interferon, the dendritic lesion disappeared and herpes simplex culture became negative. Six months later a carcinoma of the larynx was diagnosed. The acyclovir-resistant herpetic keratitis may be associated with the carcinoma because resistant herpes simplex virus strains are predominantly described in patients suffering from immune deficiency.

Acyclovir↗