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M Gardiner

Publications and source records attributed to M Gardiner.

At least 19 recordsLinked to original sources
PubMed2000

Genetics of the epilepsies.

Molecular genetic analysis of mendelian epilepsies in humans and mice has revealed a diversity of underlying genes in symptomatic epilepsies associated with disordered brain development and neuronal survival. In contrast, the idiopathic mendelian epilepsies have emerged as a new category of channelopathies. New epilepsy loci have been mapped and one new epilepsy gene isolated. Functional analysis of epilepsy genes is providing new insights into the pathways that lead from mutant gene to hyperexcitable neurones. The major challenge for the future is the analysis of genetic epilepsies with complex inheritance.

Animals↗
PubMed1999

Molecular genetics of the neuronal ceroid lipofuscinoses.

The neuronal ceroid lipofuscinoses (NCLs) are a group of inherited neurodegenerative disorders characterised by the accumulation of autofluorescent storage material in neurons and other cell types. The clinical features include visual impairment, progressive myoclonic epilepsy, and cognitive decline reflecting progressive neurodegeneration. The NCLs are subdivided into several subtypes according to age of onset, clinical course, and ultrastructure of the storage material. The molecular genetic basis of this group of disorders has recently been clarified. Mutations in the gene encoding a lysosomal enzyme, palmitoyl protein thioesterase (PPT), cause infantile NCL (locus CLN1 on chromosome 1p32) or Haltia-Santavuori disease. This Finnish disease is characterised ultrastructurally by granular osmiophilic deposits (GRODs). Juvenile-onset NCL with GRODs also is caused by mutations in PPT. Classic late-infantile NCL (Jansky-Bielschowsky disease) is caused by mutations in a gene encoding a pepstatin-insensitive lysosomal peptidase (CLN2 on chromosome 11p15), and juvenile-onset NCL (Batten disease) is caused by mutations in a gene encoding a 438-amino-acid membrane protein (CLN3 on chromosome 16p12) of unknown function. A locus for Finnish variant late-infantile NCL, CLN5, has been mapped to chromosome 13q22 and a locus for variant late-infantile NCL, CLN6, to chromosome 15q21-23. These and further advances will allow the molecular basis of the NCLs to be elucidated and may lead to new strategies for diagnosis and treatment.

Adolescent↗
PubMed1996

Clinical assessment of the 1987 American College of Rheumatology criteria for rheumatoid arthritis.

The 1987 American College of Rheumatology (ACR) criteria for the classification of rheumatoid arthritis (RA) were clinically assessed. These criteria do not include findings of synovial fluid (SF) analysis and require no exclusion criteria. We have studied sequential patients with arthritis seen in four rheumatology centers in the Philadelphia area. Classifications by the ACR criteria were compared with our clinical diagnoses. Two hundred ninety eight patients were evaluated, 113 with RA and 185 with other diagnoses. Classifications as RA by the ACR criteria corresponded to our clinical diagnosis in 95% of the cases, corroborating the high sensitivity previously reported. However, we found a lower specificity (73%) than that reported (89%). False positive classifications as RA were found in 71% of patients with psoriatic arthritis, 48% of patients with SLE, and 31% of patients with gout. The specificity could be improved to 89% by excluding disorders with obvious distinguishing extraarticular features such as psoriasis or by SF findings of monosodium urate crystals. Awareness of these possible sources of confusion will further increase the teaching and epidemiologic value of these useful simplified criteria.

Adult↗
PubMed1996

Genetic evidence for the neuronal nitric oxide synthase gene (NOS1) as a susceptibility locus for infantile pyloric stenosis.

The etiological role of the gene for neuronal nitric oxide synthase (NOS1) in infantile pyloric stenosis (PS) was investigated by analysis of two intragenic polymorphisms (NOS1a and NOS1b) in 27 families. There was significant overall transmission disequilibrium between PS and NOS1a (P = .006). Consideration of each allele independently revealed a highly significant tendency for allele 7 (210 bp) to be preferentially transmitted to the affected offspring (P = .0006). These observations suggest that NOS1 is a susceptibility locus for PS.

Alleles↗
PubMed1995

Linkage analysis of late-infantile neuronal ceroid-lipofuscinosis.

The neuronal ceroid-lipofuscinoses (NCL) are a group of neurodegenerative disorders with an autosomal-recessive pattern of inheritance. There are 3 main categories of childhood NCL, namely, infantile, late-infantile, and juvenile NCL. These can be distinguished on the basis of age of onset, clinical course, and histopathology. A number of variant forms of NCL have also been described, and these show symptoms intermediary between the main classical forms. The genes for both the infantile and juvenile forms of NCL have previously been mapped to chromosome areas 1p32 and 16p12, respectively. The gene for late-infantile NCL (LINCL), CLN2, has been excluded from both these loci, but its location is as yet unknown. Recently, CLN5, the gene for the Finnish variant form of LINCL, was mapped to 13q21.1-32. Using the 3 microsatellite markers which were most tightly linked to CLN5, we have excluded CLN2 from this region using a subset of 17 families. Thus, CLN2 represents a fourth distinct genetic locus involved in the pathogenesis of NCL.

Age of Onset↗
PubMed1995

Genetics of the epilepsies.

The epilepsy gene map has been refined and extended with new information concerning benign familial neonatal convulsions, benign familial infantile convulsions, Unverricht-Lundborg disease, epilepsy with progressive mental retardation and juvenile myoclonic epilepsy. Understanding of the molecular basis of paroxysmal disorders affecting the central nervous system has been revolutionalized with the identification of mutations in genes for the neurotransmitter receptors, GLRA1 and CHRNA4, and a voltage-gated potassium channel, KCNA1, as causes of inherited neurological disease.

Adolescent↗
PubMed1994

Defined chromosomal assignment of CLN5 demonstrates that at least four genetic loci are involved in the pathogenesis of human ceroid lipofuscinoses.

We demonstrate here that at least four genetically separate loci are involved in the pathogenesis of human neuronal ceroid lipofuscinoses (NCLs), fatal brain disorders of children. Earlier the assignments of the infantile and juvenile subtypes of NCL to 1p32 and 16p12 had revealed two loci; and here a variant subtype of the late-infantile form of NCL is mapped to a well-defined region on 13q21.1-q32, whereas the clinically similar, classical form of late-infantile NCL was found to represent the fourth, yet-unidentified NCL locus. The linkage disequilibrium was crucial for locus assignment in our highly limited family material, and the data exemplify the significance of this phenomenon in the random mapping of rare human diseases.

Child↗
PubMed1990

Batten disease (Spielmeyer-Vogt disease, juvenile onset neuronal ceroid-lipofuscinosis) gene (CLN3) maps to human chromosome 16.

The ceroid-lipofuscinoses are a group of inherited neurodegenerative disorders characterized by the accumulation of autofluorescent lipopigment in neurons and other cell types. The underlying biochemical defect is unknown. Batten disease (Spielmeyer-Vogt disease, juvenile onset neuronal ceroid-lipofuscinosis) displays autosomal recessive inheritance. Genetic linkage studies were undertaken to determine the chromosomal location of the Batten disease mutation (CLN3). Following identification of linkage to the haptoglobin locus, linkage analysis has been carried out in 42 families by using DNA markers for loci on the long arm of human chromosome 16. The maximal lod score between Batten disease and the locus D16S148 calculated for combined sexes is 6.05 at a recombination fraction theta = 0.00. Multilocus analysis using five loci indicated the most likely order to be HP-D16S151-D16S150-CLN3-D16S148-D16S147. The maximal location score for CLN3 was 48 (equivalent to a lod score of 10.4) in that interval within this fixed marker map.

Chromosome Mapping↗
PubMed1985

Sublethal hemorrhage impairs the acute peritoneal inflammatory response in the rat.

Hemorrhagic shock increases the risk of septic complications in injured patients. In this study, we investigated the effect of sublethal hemorrhage on the acute peritoneal inflammatory response and the clearance of bacteria from the peritoneal cavity of the rat. Sprague-Dawley rats were subjected to sublethal hemorrhage, resuscitated, and then inoculated intraperitoneally with a suspension of viable Escherichia coli in saline. Sham-hemorrhaged rats served as controls. Sublethal hemorrhage decreased survival and impaired the influx into the peritoneum of polymorphonuclear leukocytes and macrophage colony-forming cells. There was no difference between groups in the clearance of viable bacteria from the peritoneum; clearance of blood-borne bacteria was decreased in the hemorrhaged animals. We conclude that sublethal hemorrhage in the rat inhibits the acute peritoneal inflammatory response, but has little or no effect on the early removal of bacteria from the peritoneal cavity.

Animals↗
PubMed1983

Reality orientation with elderly patients in the community: an empirical evaluation.

There is now good evidence that elderly mentally impaired patients can be re-orientated for time, place and person using the technique of reality orientation (RO). To date, all empirical trials demonstrating this have been carried out on elderly institutionalized patients. This technique however might be of greater value to those elderly dementing patients still living with relatives in the community but attending geriatric psychiatry day hospitals, where they could receive RO in a consistent and systematic way. The results of an empirical study of RO with a group of such patients is reported. These showed that day hospital patients could be effectively re-orientated and that concomitant with changes in level of orientation of the patients, there were parallel changes in the patients' behaviour at home, reported stress on relatives and in relatives' mood.

Aged↗
PubMed1982

Influence of blood glucose concentration on brain lactate accumulation during severe hypoxia and subsequent recovery of brain energy metabolism.

The effects of hypoxaemia on regional cerebral blood flow (CBF) and brain cortical metabolite concentrations were investigated at different blood glucose concentrations in rats under nitrous oxide anaesthesia. Tissue hypoxia of 15-min duration was induced by a combination of arterial hypoxaemia, hypotension, and clamping of the right carotid artery. Blood glucose concentrations were manipulated by varying the food intake in the 24 h before the experiment, and by glucose administration. Cortical CBF doubled during hypoxia on the intact side, but did not differ significantly from control values on the clamped side. In the clamped hemisphere there was a substantial decrease in adenylate energy charge. At brain tissue glucose concentration of 1 mumol g-1 and above, there was an inverse correlation between adenylate energy charge and brain lactate concentration. In starved animals with mean brain glucose of 0.32 +/- 0.00 mumol g-1, lactate concentration was significantly lower, in spite of equally severe disruption of energy state. Recovery of brain adenylate energy charge was worse in fed and glucose-infused groups than in the fasted group. These results demonstrate that limitation of substrate supply during severe hypoxia in the rat allows enhanced recovery of brain energy metabolism following the hypoxic episode.

Animals↗