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J Trojanowski

Publications and source records attributed to J Trojanowski.

At least 19 recordsLinked to original sources
PubMed2002

Analysis of tau haplotypes in Pick's disease.

Pick's disease (PiD) is characterized by the deposition of tau protein as three-repeat tau Pick bodies, whereas progressive supranuclear palsy (PSP) involves the deposition of four-repeat tau neurofibrillary tangles. PSP is associated with the tau H1 haplotype. The authors investigated a possible association between PiD and the tau H1 or H2 haplotype. There was no difference between the tau H2 haplotype or H2H2 genotype frequency in PiD cases and control subjects. No tau mutations were identified in pathologically typical cases of PiD, with antibody 12-E8-negative Pick bodies.

Aged↗
PubMed1998

Association of missense and 5'-splice-site mutations in tau with the inherited dementia FTDP-17.

Thirteen families have been described with an autosomal dominantly inherited dementia named frontotemporal dementia and parkinsonism linked to chromosome 17 (FTDP-17), historically termed Pick's disease. Most FTDP-17 cases show neuronal and/or glial inclusions that stain positively with antibodies raised against the microtubule-associated protein Tau, although the Tau pathology varies considerably in both its quantity (or severity) and characteristics. Previous studies have mapped the FTDP-17 locus to a 2-centimorgan region on chromosome 17q21.11; the tau gene also lies within this region. We have now sequenced tau in FTDP-17 families and identified three missense mutations (G272V, P301L and R406W) and three mutations in the 5' splice site of exon 10. The splice-site mutations all destabilize a potential stem-loop structure which is probably involved in regulating the alternative splicing of exon10. This causes more frequent usage of the 5' splice site and an increased proportion of tau transcripts that include exon 10. The increase in exon 10+ messenger RNA will increase the proportion of Tau containing four microtubule-binding repeats, which is consistent with the neuropathology described in several families with FTDP-17.

Alternative Splicing↗
PubMed1998

Dementia resulting from dural arteriovenous fistulas: the pathologic findings of venous hypertensive encephalopathy.

PURPOSE: Dural arteriovenous fistulas (DAVFs) are acquired arteriovenous shunts located within the dura. The highly variable natural history and symptomatology of DAVFs range from subjective bruit to intracranial hemorrhage and are related to the lesion's pattern of venous drainage and its effect on the drainage of adjacent brain. We examined the prevalence and features of DAVFs in patients with progressive dementia or encephalopathy. METHODS: The records and radiologic studies of 40 consecutive patients with DAVFs treated at our institution were reviewed. RESULTS: Five (12.5%) of 40 consecutive patients with DAVFs had encephalopathy or dementia. In each patient, high flow through the arteriovenous shunt combined with venous outflow obstruction caused impairment of cerebral venous drainage. Hemodynamically, the result was widespread venous hypertension causing diffuse ischemia and progressive dysfunction of brain parenchyma. Results of CT or MR imaging revealed abnormalities in each patient, reflecting the impaired parenchymal venous drainage. Pathologic findings in one patient confirmed the mechanism of cerebral dysfunction as venous hypertension. The hemodynamic mechanism and resulting abnormality appeared identical to that seen in progressive chronic myelopathy resulting from a spinal DAVF (Foix-Alajouanine syndrome). Remission of cognitive symptoms occurred in each patient after embolization. CONCLUSION: Venous hypertensive encephalopathy resulting from a DAVF should be considered a potentially reversible cause of vascular dementia in patients with progressive cognitive deficits.

Aged↗
PubMed1989

Remarkable intron and exon sequence conservation in human and mouse homeobox Hox 1.3 genes.

A high degree of conservation exists between the Hox 1.3 homeobox genes of mice and humans. The two genes occupy the same relative positions in their respective Hox 1 gene clusters, they show extensive sequence similarities in their coding and noncoding portions, and both are transcribed into multiple transcripts of similar sizes. The predicted human Hox 1.3 protein differs from its murine counterpart in only 7 of 270 amino acids. The sequence similarity in the 250 base pairs upstream of the initiation codon is 98%, the similarity between the two introns, both 960 base pairs long, is 72%, and the similarity in the 3' noncoding region from termination codon to polyadenylation signal is 90%. Both mouse and human Hox 1.3 introns contain a sequence with homology to a mating-type-controlled cis element of the yeast Ty1 transposon. DNA-binding studies with a recombinant mouse Hox 1.3 protein identified two binding sites in the intron, both of which were within the region of shared homology with this Ty1 cis element.

Amino Acid Sequence↗
PubMed1988

Catabolism of single ring aromatic acids by four Aspergillus species.

Four species of the genus Aspergillus, viz A. fumigatus, A. japonicus, A. niger and A. terreus, decarboxylated, demethoxylated and ring-cleaved aromatic compounds but to different extents. Decarboxylation of vanillate occurred before ring-cleavage, which preceded the release of 14CO2 from the methoxyl group. A large proportion of labelled carbon from the ring of ferulate and vanillate was found in particulate or trichloracetic acid precipitable material of homogenized fungal mycelium. The four Aspergillus species contained vanillate-inducible protocatechuate-3,4-dioxygenase and catechol-1,2-dioxygenase activities.

Aspergillus fumigatus↗
PubMed1985

Combined immunostaining of neurofilaments, neuron specific enolase, GFAP and S-100. A possible means for assessing the morphological and functional status of the enteric nervous system.

Neurofilaments, part of the cytoskeletal network, and neuron specific enolase, a major enzyme in glycolysis, are both present in central and peripheral neurons. Glial fibrillary acidic protein and S-100, on the other hand, are soluble proteins which are found exclusively in the supportive cells of the nervous system, i.e. the glial cells. Examination was made, using immunocytochemistry, of all main areas of the gastrointestinal tract of three mammalian species, rat, pig and man. By applying serial tissue sectioning, it was possible to study the relative occurrences of the two neuronal markers in the same cell bodies and to examine the relationships of the neurons with the glial cells as revealed by the antibodies to glial fibrillary acidic protein and S-100. Both neurofilaments and neuron specific enolase were localised to an extensive system of enteric nerves, with the level of neuron specific enolase-immunoreactivity showing greater variability than that observed using antibodies to neurofilaments. Comparison of the occurrence of neuron specific enolase and neurofilament immunoreactivity in serially sectioned neuronal cell bodies revealed that a minor population stained only with antibodies to neurofilaments. The equivocal or absent neuron specific enolase-immunoreactivity in some perikarya may reflect variations in functional status within the nervous system. Glial fibrillary acidic protein- and S-100-immunoreactivities were confined to glial cells which, in this normal tissue, were always in close association with the neurons.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1985

Familial pineoblastoma. Report of two cases.

Two cases of pineoblastoma are presented. One occurred in a 12-year-old girl and the other, 20 months later, in her 43-year-old mother. A possible genetic basis and mutual exposure to an environmental factor responsible for the expression of a tumor gene are postulated in the discussion.

Adult↗
PubMed1983

Aromatic ring cleavage of protocatechuic acid by the white-rot fungus Pleurotus ostreatus.

In Pleurotus ostreatus protocatechuic acid is degraded by protocatechuate 3,4-dioxygenase (protocatechuate: oxygen 3,4-oxidoreductase, EC 1.13.11.3) via "intradiol" cleavage of aromatic ring to form beta-carboxy-cis,cis-muconic acid. The enzyme was isolated from the mycelium induced with p-hydroxybenzoic acid. An about 460-fold purification of the enzyme was achieved by ammonium sulphate fractionation, and DEAE-cellulose and Sephadex G-200 chromatography. The enzyme was homogeneous on analytical electrophoresis under non-denaturing conditions, whereas in the presence of sodium dodecyl sulphate several polypeptides of low molecular weight appeared additionally in trace amounts. Molecular weight of the enzyme, determined by gel filtration and electrophoresis was 200 000 and 205 000, respectively. The enzyme showed low substrate specificity, its pH optimum was 8.0 and Michaelis constant for protocatechuic acid was 14.2 microM.

Basidiomycota↗
PubMed1982

Cellulolytic activity of moulds. I. Characteristics of the cellulases complex and xylanase of the strain Aspergillus terreus F-413.

Among 79 strains of moulds belonging to 17 different species, the strain Aspergillus terreus F-413 which showed the highest cellulolytic activity was isolated for further studies. Some properties of the complex of cellulases formed by this strain as well as the dynamics of their synthesis under optimal submerged culture conditions were characterized.

Aspergillus↗
PubMed1980

Biotransformation of sodium lignosulfonates of different molecular weights by the fungus Pleurotus ostreatus.

Fractions of sodium lignosulfonates (NaLS) of varied molecular weight, obtained by gel-permeation chromatography on Sephadex G-50, were exposed to microbiological degradation using liquid cultures of Pleurotus ostreatus. The intensity of transformation observed during 4 weeks of growth (based on nitroso determinations) was inversely proportional to the molecular weight of the fractions studied. Degradation of lignosulfonates was accompanied by polymerization, particularly where low molecular weight fractions were involved. The activity of p-diphenol oxidase (laccase) was stimulated by the presence of lignosulfonates. This effect was especially noticeable in the case of high molecular weight components.

Agaricales↗
PubMed1980

Purification and properties of protocatechuate 3,4-dioxygenase from Chaetomium piluliferum induced with p-hydroxybenzoic acid.

1. Protocatechuate 3,4-dioxygenase (protocatechuate : oxygen 3,4-oxidoreductase, EC 1.13.11.3) was isolated from mycelium of Chaetomium piluliferum induced with p-hydroxybenzoic acid. The enzyme was purified about 80-fold by ammonium sulphate fractionation and DEAE-cellulose and Sephadex G-200 chromatography, and was homogeneous on polyacrylamide-gel electrophoresis. 2. The enzyme showed high substrate specificity; its pH optimum was 7.5-8.0, and molecula weight about 76 000 as determined by filtration on Sephadex G-200. The Michaelis constant for protocatechuic acid was 11.1 microM.

Ascomycota↗
PubMed1978

Screening for lignin degrading bacteria by means of 14C-labelled lignins.

Several Nocardia and Pseudomonas spp., as well as some unidentified bacteria, isolated from lake water containing high loads of waste lignin, were tested for their capacity to release 14CO2 from specifically 14C-labelled dehydropolymer of coniferyl alcohol (DHP) or corn stalk lignins. The bacteria were selected according to their ability to degrade phenolic compounds. However, only some of them could release significant amounts of 14CO2 from the labelled lignin. The tested Nocardia spp. were more active than the Pseudomonas spp. and the unidentified bacteria. The most active strains belonged to N. autotrophica. These strains released CO2 significantly from the methoxyl group and transformed the other carbons from the phenylpropane skeleton of lignin also into CO2. Other less demethylating strains also released little CO2 from the other carbons of the lignin molecule. From corn stalk materials which were specifically labelled in the lignin part, only small amounts of labelled CO2 were released.

Biodegradation, Environmental↗
PubMed1978

Induction of laccase in Basidiomycetes: the laccase-coding messenger.

Formation of the mRNA specific for the inducible forms of laccase was evidenced in Coriolus versicolor, Pleurotus ostreatus and Pholiota mutabilis. The half-life time of these mRNAs in the fungi species studied were, respectively, 30, 37 and 24 min. Molecular weight of the newly synthesized mRNA in Pleurotus ostreatus was about 4.5X10(5), consistently with the size of the inducible laccase protein. The polysome obtained from the ferulic acid-treated mycelium, synthesized in vitro a polypeptide with the electrophoretic mobility similar to that of laccase.

Basidiomycota↗
PubMed1978

Induction of laccase in Basidiomycetes: apparent activity of the inducible and constitutive forms of the enzyme with phenolic substrates.

The purified preparations of the inducible and constitutive forms of laccase (EC 1.14.18.1) have been obtained from mycelia of Trametes versicolor, Pleurotus ostreatus and Pholiota mutabilis. The activities of the inducible forms of laccase with ferulic acid and other phenolic hydrogen donors were found to be several-fold higher as compared with the constitutive forms.

Basidiomycota↗
PubMed1978

Bacterial decomposition of synthetic 14C-labeled lignin and lignin monomer derivatives.

Nocardia sp. which was isolated from soil is capable of degrading synthetic lignin and utilizing its monomer derivatives. Decomposition was monitored by measuring the 14CO2 evolved and O2 consumed, when the bacterium was grown on a medium containing specifically 14C-labeled ligning or monomer phenolic compounds as major carbon source. The time course of the 14CO2 release and O2 uptake indicates a significant depolymerization and utilization of lignin by the Nocardia sp.

Anisoles↗