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A Bogucki

Publications and source records attributed to A Bogucki.

At least 19 recordsLinked to original sources
PubMed1992

Single-stranded DNA as a recombination substrate in plants as assessed by stable and transient recombination assays.

Two separate assays, one that requires stable integration of recombination products and one that does not, were employed to elucidate the role of single-stranded DNA in extrachromosomal homologous recombination in Nicotiana tabacum. Both assays revealed that single-stranded DNA in linear and in circular forms was an efficient substrate for recombination, provided that the cotransformed recombination substrates were of complementary sequence, so that direct annealing was possible. Recombination was inefficient when both single-stranded recombination partners contained homologous regions of identical sequence and generation of a double-stranded DNA was required prior to heteroduplex formation. These results indicate that direct annealing of single strands is an important initial step for intermolecular recombination in tobacco cells. Annealed cotransformed single-stranded molecules yielded intermediates that could be further processed by either continuous or discontinuous second-strand synthesis. The type of intermediate had no influence on the recombination efficiency. Double-stranded circles were unable to recombine efficiently either with each other or with single-stranded DNA. Our results suggest that a helicase activity is involved in the initial steps of double-stranded DNA recombination which unwinds duplex molecules at the site of double-strand breaks.

Base Sequence↗
PubMed1991

Amyloid beta-protein in cerebral amyloid angiopathy, senile plaques, and preamyloidotic lesions in subcortical arteriosclerotic encephalopathy (Binswanger disease).

Cerebral vascular amyloid deposits, senile plaques and neurofibrillary tangles have been found in subcortical arteriosclerotic encephalopathy (Binswanger disease). A mouse antiserum, prepared against a 43-amino acid synthetic peptide homologous to the amyloid beta-protein of Alzheimer disease (anti-SP43), revealed immunoreactive amyloid deposits in meningeal and intracortical blood vessels, senile plaques, intraneuronal amyloid and preamyloid in a neuropathologically confirmed case of Binswanger disease previously reported to have cerebral vascular amyloid deposits. These lesions contained sulfated glycosaminoglycans as determined by the Alcian blue/critical electrolyte concentration method. Similar findings were not observed in a case of Binswanger encephalopathy without cerebral amyloid deposits. Our study indicates that amyloidotic lesions in Binswanger encephalopathy with cerebral amyloid deposits contain amyloid beta-protein and sulfated glycosaminoglycans.

Amyloid beta-Peptides↗
PubMed1991

Evaluation of dementia in subcortical arteriosclerotic encephalopathy (Binswanger's disease).

Sixteen patients with a clinical diagnosis of subcortical arteriosclerotic encephalopathy (Binswanger's disease) were studied. Mild or moderate dementia was found in 14 cases, with characteristic disturbances of concentration, and psychic retardation with apathy. Neuropsychological studies revealed that signs of diffuse lesions in the frontal lobes dominated. Impairment of memory was significant in all cases. Although intellectual impairment in subcortical arteriosclerotic encephalopathy resembled subcortical dementia, some significant differences were found.

Activities of Daily Living↗
PubMed1990

Studies on nitroglycerin and histamine provoked cluster headache attacks.

Attacks of cluster headache provoked by the administration of nitroglycerin (1 mg sublingually) or histamine (0.01 mg/kg subcutaneously) were studied. The constant latency time in individual patients during nitroglycerin and histamine provocation suggested that the same mechanism is involved in both methods of headache induction. Repeated nitroglycerin provocation revealed its tendency to lengthen duration of the refractory period at the end of the bout, when the attacks were less frequent. The "cross studies" on spontaneous and nitroglycerin provoked attacks indicated that the underlying mechanism of both is at least partially the same.

Adult↗
PubMed1989

[So-called cervicogenic headache].

After a description of the clinical pattern of the newly isolated by Sjaastad et al. from of headaches, that is cervicogenic headache the authors report two own cases in women aged 37 and 57 years. The cases agreed completely with the description of Sjaastad et al. and other authors, and they enrich the number of case reports on this disease.

Adult↗
PubMed1989

Isolation and purification of scrapie-associated fibrils and prion protein from scrapie-infected hamster brain.

We report the purification of prion protein (PrP) 27-30 and scrapie-associated fibrils (SAF) from hamsters infected with the 263K strain of scrapie. SDS-PAGE of fractions purified from scrapie-infected brains revealed several bands at approximately 28.5 kDa, 23.9 kDa and 14.3 kDa and, in one set of preparations, a protein of Mr 26 kDa was found in both scrapie-infected and sham-inoculated animals. The specificity of PrPs was confirmed by Western blotting. Ultrastructural analysis of fractions from scrapie-infected brains revealed numerous fibrils measuring approximately 20 nm in diameter and 100 to 200 nm in length. The substructure of these fibrils consisted of protofilaments which were usually straight and rarely helically arranged. We conclude that the electron microscopical appearance of SAF depends much on the purification scheme. The PrP27-30 as well as proteins of lower Mr are easily detectable in scrapie-infected brains. The detection of protein of a Mr 26 kDa in both scrapie-infected and sham-inoculated animals suggests that this form of PrP may exist in equilibrium with PrP33-35c.

Animals↗
PubMed1989

Ultrastructural studies of scrapie-associated fibrils and prion protein from hamster brains infected with scrapie.

We report here about the purification of prion protein 27-30 (PrP 27-30) and scrapie-associated fibrils (SAF) from hamsters infected with the 263K strain of scrapie. Ultrastructural analysis of fractions from scrapie-infected brains revealed numerous fibrils measuring approximately 20 nm in diameter and 100-200 nm in length. The substructure of these fibrils consisted of protofilaments which were usually straight and rarely helically arranged. We conclude that the electron microscopic appearance of SAF depends much on the purification scheme.

Animals↗
PubMed1988

Cerebral amyloid angiopathy with attenuation of the white matter on CT scans: subcortical arteriosclerotic encephalopathy (Binswanger) in a normotensive patient.

Subcortical arteriosclerotic encephalopathy was diagnosed in a 56-year-old female normotensive patient with gradually progressing dementia, pseudobulbar palsy and motor deficits. CT scan showed white matter low attenuation in the frontal and parietal lobes. Neuropathological examination revealed degeneration of the white matter. Amyloid was found in walls of small cortical vessels. The walls of small vessels in the white matter showed severe thickening, fibrosis and hyalinization but not amyloid. Cerebral amyloid angiopathy may be responsible for subcortical arteriosclerotic encephalopathy.

Amyloid↗
PubMed1988

Cervicogenic headache. Pupillometric findings.

Eleven female patients with cervicogenic headache (mean age, 43 years; range, 25-59 years) have been examined with the pupillometer. The pupillary diameter was examined in the basal state (that is, the status before pharmacologic stimulation) and after topically administered tyramine (2%), phenylephrine (1%), and hydroxyamphetamine (1%). A total of 51 tests were performed, 35 in the asymptomatic period and 16 during pain attacks. In a control group consisting of 26 age-matched women a total of 39 tests were carried out. Before pharmacologic stimulation (that is, in the "basal state") the pupils were smaller in the asymptomatic (pain-free) period than during pain attacks in the patients and also as compared with that of control individuals. The anisocoria (the difference in pupillary size in the same individual) observed was not significantly different between the patient group and control individuals either in the basal state (before pharmacologic stimulation) or after pharmacologic stimulation. The mydriasis resulting from the instillation of the three sympathicomimetic drugs was symmetrical in both controls and patients both during and between the pain attacks. This finding is in clear contrast to what is found in cluster headache, in which there is a "Horner-like" syndrome on the symptomatic side. These two headaches thus seem to differ essentially with regard to this variable.

Adult↗
PubMed1987

Sympathetic iris function in amyotrophic lateral sclerosis.

Autonomic fibres are generally regarded as being spared in amyotrophic lateral sclerosis. Anatomical studies have cast some doubt upon this hypothesis. The present study describes the pupillary responses to tyramine, a norepinephrine releaser, and to phenylephrine, a directly acting sympathomimetic, in 11 patients with ALS and matched controls. Patients and controls showed a similar sensitivity to sympathomimetic agents, and our results lend some support to the hypothesis that sympathetic functions are not involved in ALS.

Adult↗
PubMed1987

Sweat gland and pupillary responsiveness in Horner's syndrome.

Eight patients with Horner's syndrome (five with a 1st neuron lesion and three with a 2nd neuron lesion) were examined for their pupillary responses to pharmacologic stimulation with tyramine (2%) and with phenylephrine (1%) eye drops. The same patients were also evaluated for their forehead sweating pattern on stimulation with body heating and pilocarpine injection, using the Evaporimeter. Five patients had a brain stem (1st sympathetic neuron) lesion, while three patients had had a traumatic C8-Th1 root avulsion and hence had a preganglionic neuron lesion. The average response with the phenylephrine eye test and the pilocarpine sweat test differed markedly between the two groups; only the central neuron lesion group had a supersensitivity reaction to both drugs. These procedures may be of diagnostic value in localizing the lesion in patients with a Horner's syndrome of unknown etiology. Patients with 3rd neuron lesion have not been examined with this combination of techniques.

Aged↗
PubMed1987

Cluster headache pathogenesis: a pupillometric study.

Thirty-two cluster headache patients and healthy controls (n = 16-20 for the various tests) were examined by means of a Whitaker pupillometer during pain-free intervals. Eye drops of the sympathomimetic agents tyramine, hydroxyamphetamine, and phenylephrine were instilled into the conjunctival sacs on separate occasions, and pupillary diameters recorded at standard time intervals. The mydriatic responses of the two pupils were compared. A moderate, but statistically significant, basal relative miosis was found on the pain side in cluster headache. The symptomatic-side pupils were less responsive than their counterparts when stimulated with tyramine and hydroxyamphetamine, the difference being statistically significant for the OH-amphetamine test. With the phenylephrine test, however, the mydriasis on the symptomatic side significantly exceeded that of the contralateral pupil. This pattern of reactions does not quite correspond to those of "ordinary" Horner's syndrome (1st, 2nd, and 3rd neuron lesion). There are, however, gross similarities with the recently reported pattern in central sympathetic neuron dysfunction. In cluster headache there is probably a "Horner-like picture" rather than a proper Horner's syndrome.

Adult↗
PubMed1986

Brain histamine metabolism in transmissible spongiform encephalopathy (scrapie).

The histamine (Hi) content and the activity of L-histidine decarboxylase (HD) in brains of scrapie infected hamsters were measured. No significant changes in Hi levels in particular brain areas were found when compared to controls. Decreased activity of HD was found in hypothalamus (p less than 0.02). Increased activity of the enzyme was observed in "rest of brain", which consisted mainly of thalamus and striatum (p less than 0.05).

Animals↗
PubMed1985

Cluster headache: histamine skin tests in the painful area.

Histamine skin tests were performed in the painful area and on the opposite side in ten cluster headache patients. The studies were carried out with and without local anaesthesia. No differences between histamine skin response in the painful region compared with the contralateral side were revealed. This study concerns the part of the triple response which is the result of a direct action of histamine on the skin vasculature (mediated by both H1 and H2) histaminergic receptors, i.e. wheal and redness, and the flare, which is the result of neurohumoral mechanisms.

Adult↗