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A D Patrick

Publications and source records attributed to A D Patrick.

At least 19 recordsLinked to original sources
PubMed1992

Stored dolichyl pyrophosphoryl oligosaccharides in Batten disease.

Each of the 3 childhood forms of Batten disease, juvenile (JB), late-infantile (LIB), and infantile (IB), have abnormally high brain concentrations of dolichyl pyrophosphoryl oligosaccharides (Dol-PP-OS). In this study, the carbohydrate portions of Dol-PP-OS were analysed: in JB and LIB, they range in size from Man2GlcNAc2 to Glc3Man9GlcNAc2, predominant components being Man5-7GlcNAc2 and Glc3Man7GlcNAc2. In IB, they range from Man6-9GlcNAc2, no glucose containing oligosaccharides being identified. In Batten disease, the main subcellular location of Dol-PP-OS is within storage material, where it represents up to 7% of the dry weight. [3H]-Mannose incorporation experiments with cultured fibroblasts show that synthesis of Dol-PP-OS in JB is normal. We infer that the glycosylation intermediate Glc3Man9GlcNAc2-PP-dolichol is synthesised normally within the endoplasmic reticulum in Batten disease, but that catabolic derivatives accumulate within the lysosomes. It is unclear whether this process is central to the pathogenesis of the disease, though in IB a defect in the release of mannose residues from Dol-PP-OS is a distinct possibility.

Carbohydrate Sequence↗
PubMed1991

Lysosomal storage of subunit c of mitochondrial ATP synthase in Batten's disease (ceroid-lipofuscinosis).

Immunochemical studies demonstrate that subunit c of mitochondrial ATP synthase is stored in the late-infantile, juvenile and adult forms of Batten's disease. It does not accumulate in the infantile form, or in other conditions involving lysosomal hypertrophy. These results suggest that the defective metabolism of subunit c is central to the pathogenesis of these three forms of Batten's disease.

Aged↗
PubMed1991

Recent biochemical and genetic advances in our understanding of Batten's disease (ceroid-lipofuscinosis).

Protein is the major component of the intra-lysosomal storage material which characteristically accumulates in Batten's disease. In the late-infantile, juvenile and adult forms of the disease, and in a form affecting sheep, this protein is principally composed of a single polypeptide, subunit c of mitochondrial ATP synthase. Subunit c is not stored in the infantile form of Batten's disease, supporting recent genetic data which suggest this is a distinct disease. Nor is subunit c found in storage material within other lysosomal storage diseases or in lipofuscin of old age. Subunit c storage, therefore, is specific for the later-onset forms of Batten's disease and indeed may be central to their aetiology.

Adult↗
PubMed1989

Analysis of dolichyl pyrophosphoryl oligosaccharides in purified storage cytosomes from ovine ceroid-lipofuscinosis.

Ovine ceroid-lipofuscinosis is an inherited neurodegenerative disorder characterised by the accumulation of storage cytosomes in brain and visceral organs. Phosphorylated dolichol-containing compounds, largely in the form of dolichyl pyrophosphoryl oligosaccharides, have been shown to constitute 1-2% of the dry weight of storage cytosomes isolated from brain and pancreas, and 0.5 and 0.1% respectively of storage cytosomes isolated from liver and kidney. The carbohydrate portion of these glyconjugates in storage cytosomes isolated from brain, pancreas and liver consisted of a series of oligosaccharides of composition Man2-9GlcNAc2, with Man5-8GlcNAc2 predominating. The concentrations of dolichyl pyrophosphoryl oligosaccharides in storage cytosomes from ovine ceroid-lipofuscinosis are much higher than has been reported for endoplasmic reticulum, their normal functional location.

Animals↗
PubMed1989

A high-performance liquid chromatography method for the analysis of picomole amounts of oligosaccharides.

A method for the high-performance liquid chromatography separation of tritium-reduced, acetylated oligosaccharides is described. Their highly sensitive detection in column eluant is facilitated by the use of a flow radioactivity detector. The method differentiates some structural isomers and provides resolution of high-mannose oligosaccharides comparable or superior to that of other high-performance liquid chromatography methods. The detection limit is 0.3 pmol of oligosaccharide. For the detection of radioactive oligosaccharides this method is much less laborious than scintillation counting of collected peak fractions. Generation of a continuous chromatographic trace offers a particular advantage in the detection of partially resolved peaks and the visualization of peak shape. A study of some of the factors influencing acetylation and reduction has led to the development of a robust analytical method.

Animals↗
PubMed1989

Glycoconjugates in storage cytosomes from ceroid-lipofuscinosis (Batten's disease) and in lipofuscin from old-age brain.

The ceroid-lipofuscinoses (CL) are a group of inherited diseases characterised by the accumulation, in brain, of autofluorescent storage cytosomes which have similar histochemical staining properties to lipofuscin, the neuronal wear and tear pigment of old-age brain. The storage cytosomes stain strongly with periodic acid-Schiff reagent (PAS), indicating the presence of carbohydrate. In brain from each childhood form of CL, concentrations of phosphorylated dolichol (Dol-P) are 10- to 20- fold higher than in age-matched controls. Brain Dol-P concentrations are also increased between 2 and 5- fold in several different lipidoses and in elderly subjects. Much of the Dol-P which accumulates is located within the storage cytosomes. Dol-P constitutes 2-3% of the dry weight of storage cytosomes from juvenile and late-infantile CL, and 0.3-0.7% of storage cytosomes from infantile CL, ovine CL and of lipofuscin isolated from old age brain. The bulk of the Dol-P in CL brain and in isolated storage cytosomes is present as dolichyl pyrophosphoryl oligosaccharides (Dol-PP-OS). The constitutions of the oligosaccharide moieties differ in the various forms of the disease. Histochemical analysis of frozen sections of unfixed brain after extraction by various lipid solvents indicates that the major part of the PAS positive intraneuronal material in CL brain and in old-age brain has the extraction properties of Dol-PP-OS. Carbohydrate represents 4-7% of the dry weight of CL storage cytosomes and of lipofuscin. The major monosaccharide components are mannose, N-acetyl glucosamine, glucose and galactose. Depending on the form of the disease studied, up to 40% of this material can be accounted for by Dol-PP-OS. Polyacrylamide gel electrophoresis of storage cytosomes followed by lectin blotting demonstrates several low molecular weight components which bind concanavalin A. These do not coelute with the major protein components and may well be Dol-PP-OS. We conclude that Dol-PP-OS are concentrated in storage cytosomes in CL and are one of their major glycoconjugate components.

Aging↗
PubMed1988

Accumulation of dolichol-linked oligosaccharides in ceroid-lipofuscinosis (Batten disease).

The accumulation of phosphorylated dolichol compounds in a number of tissues from cases of ceroid-lipofuscinosis (CL) is documented, together with an analysis of their complex carbohydrate structures. Oligosaccharides were released from dolichyl pyrophosphoryl compounds, partially purified from brain, either by mild acid hydrolysis or endoglucosaminidase digestion. The molar amounts of oligosaccharides released corresponded to the levels of P-dolichol in each brain analysed. Qualitative analysis indicated that the oligosaccharides from brain consist of a number of different components, ranging in size from four to fourteen monosaccharide units and containing chitobiose at the reducing terminal, and that the species containing seven or eight monosaccharides can be fully digested to a trisaccharide by alpha-mannosidase. The compounds that accumulate in CL tissues probably represent some of the lipid-linked intermediates known to be involved in the glycosylation of proteins, together with metabolites derived from these intermediates. The results suggest that CL might result from an impairment of the ability to metabolize dolichyl pyrophosphoryl oligosaccharides.

Adult↗
PubMed1988

Multiple sulphatase deficiency: prenatal diagnosis using chorionic villi.

Multiple sulphatase deficiency was diagnosed in the first trimester of pregnancy by demonstrating markedly reduced activities of arylsulphatases and heparin sulphamidase by direct assays on chorionic villi (CV). The diagnosis was confirmed by assays on cell cultures of villi and fetal skin fibroblasts. Two further pregnancies of this mother were monitored similarly and predicted to be unaffected; one produced a normal healthy infant, the other miscarried shortly after CV sampling.

Biopsy, Needle↗
PubMed1987

Accumulation of phosphorylated dolichol in several tissues in ceroid-lipofuscinosis (Batten disease).

The concentrations of phosphorylated dolichol (P-dolichol) and of non-phosphorylated dolichol were estimated in a number of different tissues from ceroid-lipofuscinosis (CL) and control cases. The P-dolichol contents of four tissues, brain, pancreas, muscle and kidney were significantly greater than control values. Liver and spleen showed little or no increase in P-dolichol content. Though non-phosphorylated dolichol levels were higher in CL tissues than in control tissues, the differences were significant only for brain and pancreas. In control muscle, a linear age-related increase in non-phosphorylated dolichol content was observed. The relative amounts of the major homologs of P-dolichol and of non-phosphorylated dolichol were estimated. Each tissue has a characteristic homolog size-distribution, and there is close similarity between the size-distribution profiles of P-dolichol and of non-phosphorylated dolichol for each tissue.

Adolescent↗
PubMed1987

Grey platelet syndrome: studies on platelet alpha-granules, lysosomes and defective response to thrombin.

The platelets of a young man with the grey platelet syndrome were severely depleted of all seven alpha-granule proteins assayed as well as partially deficient in alpha-mannosidase and alpha-fucosidase; four other lysosomal enzymes were present in normal concentrations. Total platelet 5-hydroxytryptamine (5HT) and adenine nucleotides were normal, and 14C-5HT uptake reached normal levels only slightly more slowly than a control. Aggregation and dense body secretion occurred normally in response to ADP, adrenaline, collagen, PAF-acether, sodium arachidonate, A23187, Ionomycin, TPA and U44069, but were very delayed in response to thrombin. The increase in cytosolic free calcium in response to thrombin was very slow and much reduced in amplitude, whether in the presence or absence of extracellular Ca2+. These defects in response to thrombin were not corrected by the separate addition of purified alpha-granule proteins or by a whole releasate from normal platelets. It is suggested that these platelets, in addition to their alpha-granule deficiency, may have a specific defect of thrombin receptor-mediated activation of phospholipase C.

Blood Platelet Disorders↗
PubMed1985

Dolichol and phosphorylated dolichol content of tissues in ceroid-lipofuscinosis.

Concentrations of free dolichol, total non-phosphorylated dolichol, and total phosphorylated dolichol were measured in autopsy specimens of brain and liver from ceroid-lipofuscinosis (CL) and control cases. Levels of non-phosphorylated dolichol, mainly as free dolichol, were increased approximately two-fold in late-infantile CL brain. No increase was observed for CL liver. In late-infantile and juvenile CL brain, the increase in phosphorylated dolichol was at least ten-fold, but no significant difference was found for CL liver. A substantial part of the increase in phosphorylated dolichol in CL brain appeared to be due to lipid-linked oligosaccharides. The results suggest that CL might involve a defect in the metabolism of dolichol-linked oligosaccharides.

Adolescent↗
PubMed1985

Acid maltase deficiency in adults. Diagnosis and management in five cases.

Five patients with adult onset acid maltase deficiency are described. All patients had developed their initial pelvic girdle symptoms late in the second or early in the third decade and some years later developed signs of respiratory insufficiency. Typically they were tall, had weak and wasted paraspinal and gluteal muscles with lower limb weakness. All were orthopnoeic with marked diaphragmatic weakness. In all patients characteristic glycogen vacuoles were seen in peripheral blood lymphocytes. Muscle biopsy was characteristic in only 1 out of 4 cases and showed minimal or nonspecific features in 3. The diagnosis was confirmed by enzyme assay in muscle and cultured fibroblasts. Long-term domiciliary ventilatory support (25 patient-years) using a rocking bed or intermittent positive pressure respiration with a tracheostomy has allowed a return to work in all patients, with their clinical condition remaining stable.

Adult↗
PubMed1984

Glutaric aciduria type II: biochemical investigation and treatment of a child diagnosed prenatally.

Two sibs with the acute neonatal form of glutaric aciduria type II (deficient in vivo activity of multiple acyl-CoA dehydrogenases) are described. In the second case diagnosis was made prenatally on the basis of reduced oxidation of palmitate by cultured amniotic fluid cells. With prompt intervention in the neonatal period and a carefully controlled diet later, this second progressed well up to 4 months of age but died suddenly of cardiac failure, probably attributable to accumulation of fat. Neither patient showed any congenital morphological abnormality. Cultured fibroblasts from the second case showed a marked defect in the oxidation of a range of substrates requiring acyl-CoA dehydrogenases for their catabolism, but residual activity for some substrates was quite high. Large quantities of sarcosine were excreted in urine, again suggesting that the mutation leaves some residual dehydrogenation activity. Butyryl-, octanoyl- and palmitoyl-CoA dehydrogenases were present in essentially normal quantities in postmortem liver.

Adipates↗
PubMed1983

Prenatal tests for Sanfilippo disease type B in four pregnancies.

We report the prenatal diagnosis of two fetuses with Sanfilippo disease type B. In both pregnancies there were excessive amounts of heparan sulphate in amniotic fluid and the activity of N-acetyl-alpha-D-glucosaminidase was undetectable in cultured amniotic fluid cells. The predictions were confirmed by enzyme assay of cultured skin fibroblasts from the aborted fetus or the affected infant. The disorder was excluded for two other pregnancies at risk and the predictions are considered to be correct because of the normal progress of the healthy children.

Acetylglucosaminidase↗