Search PubMed⌕ Search

Biomedical subjects

J Moriarty

Publications and source records attributed to J Moriarty.

At least 37 records · Page 2Linked to original sources
PubMed1995

Radiographic evaluation of alveolar crest obscured by dental implants.

This study evaluated the diagnostic accuracy of periapical, tomographic, and cross-sectional occlusal radiographic techniques in the assessment of facial and lingual bone loss at implant obscured sites. An edentulous dry human mandible was prepared with implants in the incisor, premolar, and molar regions. Successive round bur sizes (No. 1 to 6) were used to create circumferential infrabony periodontal defects in the alveolar crest adjacent to the implants. Periapical radiographs were made with custom stents and imaged each site in a conventional parasagittal orientation. Linear tomograms imaged sites in a cross-sectional coronal orientation. Cross-sectional occlusal radiographs imaged anatomy in the axial plane. Radiographic anatomy mesial and distal to each implant was masked with opaque tape before evaluation by a panel of six observers. Images were displayed in pairs consisting of an image at baseline and a second image having an equal chance of displaying an increment of bone removal or no bone removal. Image pairs were displayed in random order. A five-point scale was used to evaluate accuracy of detection of the presence or absence of changes in bone density as well as observer confidence in that assessment. ANOVA demonstrated significant variation due to image modality and increment of bone removal. Cross-sectional occlusal views provided significantly greater mean observer confidence scores than either periapical images or tomograms (P < .01). However, tomograms may provide greater utility in actual clinical practice.

Alveolar Bone Loss↗
PubMed1995

Mass versus activity: validation of an immunometric assay for bone alkaline phosphatase in serum.

A detailed investigation of the performance of an immunometric assay for the quantitation of bone alkaline phosphatase (ALP) in serum showed that precision of this assay was similar to that of lectin precipitation and electrophoretic methods. Relationships for mass and activity measurements of the bone isoform using samples from children and patients with Paget's disease were similar for lectin and electrophoretic methods. Purified liver enzyme showed 100% cross reactivity in the immunometric assay. However, comparison of the slopes between bone ALP mass and total ALP activity using only samples with predominantly liver or bone isoforms showed that the cross reactivity of the liver isoform in serum was 18.3%. Experiments in which increasing amounts of a sample containing 90% of liver isoform adding to a serum sample from a patient with Paget's disease showed a cross reactivity of 16.5%. The reference range for bone ALP mass was 7-28 micrograms/L for men (n = 77) and 5-20 micrograms/L for women (n = 110) in the age group 20-50 years. In women over 50 years bone ALP was 28% higher. Increased bone ALP mass was also demonstrated in patients with Paget's disease (n = 59), liver disease (n = 95), chronic renal failure (n = 41) and hyperthyroidism (n = 17).

Adolescent↗
PubMed1995

Brain perfusion abnormalities in Gilles de la Tourette's syndrome.

BACKGROUND: Functional brain imaging with technetium-99m d,l-hexamethyl propyleneamine oxime (HMPAO) Single Photon Emission Tomography (SPET) allows us to explore the cerebral pathophysiology of Gilles de la Tourette's Syndrome (GTS). METHOD: Fifty patients and 20 controls were examined. Patients were rated for tic severity and mood. Scans were analysed quantitatively using internal ratios to the occipital cortex. RESULTS: Patients different from controls on measures of relative blood flow to the left caudate, anterior cingulate cortex and the left dorsolateral prefrontal cortex. Severity of tics was related to hypoperfusion of the left caudate and cingulate and a left medial temporal region. Hypoperfusion in the left dorsolateral prefrontal region was related to mood. CONCLUSIONS: The areas found to be hypoperfused in this study are consistent with known functions of fronto-striatal circuits. A wide range of perfusion patterns is seen, however, and no characteristic patterns for behavioural subgroups has been documented with this technique.

Adolescent↗
PubMed1994

Striatal dopamine receptor binding in epileptic psychoses.

In order to study the nature of dopaminergic activity in epileptic psychoses we investigated striatal dopamine receptor binding in 14 patients with epilepsy. Seven of the patients were acutely psychotic when studied, having recently developed a periictal schizophreniform psychosis. The remaining patients were not psychotic. All patients were scanned using single photon emission tomography (SPET) with 123I-IBZM, a specific dopamine D2 receptor ligand. A region of interest analysis was performed. Comparison of mean basal ganglia to occipital cortex activity ratios in the two groups demonstrated significantly reduced specific binding of 123I-IBZM to striatal D2 receptors in the psychotic patients compared to those without psychosis.

Adult↗
PubMed1994

Stimulus induced behaviours in Tourette's syndrome.

Three cases of Gilles de la Tourette's syndrome (GTS) who experienced different tic related behaviours in response to both external and internal stimuli are described. Such behaviours might represent sensory tics, reflex motor tics, exaggerated startle responses, or obsessive compulsive behaviours. It is suggested that there is a continuum of stimulus induced behaviours, and that, in some cases, separations into individual descriptive entities may be difficult. There also seems to be a continuum between internal and external phenomena that induce the behaviours. Implications for the relation between GTS and obsessive compulsive disorder are also discussed.

Acoustic Stimulation↗
PubMed1994

Recognition of mental state terms. Clinical findings in children with autism and a functional neuroimaging study of normal adults.

BACKGROUND: The mind's ability to think about the mind has attracted substantial research interest in cognitive science in recent decades, as 'theory of mind'. No research has attempted to identify the brain basis of this ability, probably because it involves several separate processes. As a first step, we investigated one component process-the ability to recognise mental state terms. METHOD: In Experiment 1, we tested a group of children with autism (known to have theory of mind deficits) and a control group of children with mental handicap, for their ability to recognise mental state terms in a word list. This was to test if the mental state recognition task was related to traditional theory of mind tests. In Experiment 2, we investigated if in the normal brain, recognition of mental state terms might be localised. The procedure employed single photon emission computerised tomography (SPECT) in normal adult volunteers. We tested the prediction (based on available neurological and animal lesion studies) that there would be increased activation in the orbito-frontal cortex during this task, relative to a control condition, and relative to an adjacent frontal area (frontal-polar cortex). RESULTS: In Experiment 1, the group with autism performed significantly worse than the group without autism. In Experiment 2, there was increased cerebral blood flow during the mental state recognition task in the right orbito-frontal cortex relative to the left frontal-polar region. CONCLUSIONS: This simple mental state recognition task appears to relate to theory of mind, in that both are impaired in autism. The SPECT results implicate the orbito-frontal cortex as the basis of this ability.

Adolescent↗
PubMed1993

An idiot savant calendrical calculator with Gilles de la Tourette syndrome: implications for an understanding of the savant syndrome.

We describe the existence of the savant syndrome in association with Gilles de la Tourette's Syndrome (GTS). The presentation of savant abilities is typical of that previously described. Similarities between autism, the disorder most characteristically associated with savants, and GTS in terms of obsessionality are noted. Previously reported psychological studies of autistic savants are briefly reviewed and, together with evidence from neuroimaging in GTS, obsessive compulsive disorder (OCD), and autism, used to support a model of the underpinnings of savant skills.

Adolescent↗
PubMed1992

Hormonal regulation of major histocompatibility complex class I genes in rat thyroid FRTL-5 cells: thyroid-stimulating hormone induces a cAMP-mediated decrease in class I expression.

Thyrocytes normally express major histocompatibility complex (MHC) class I, but not class II, cell surface antigens. A rat thyrocyte cell line, FRTL-5, also expresses MHC class I antigens, in addition to a variety of thyroid-specific genes. Treatment of FRTL-5 thyrocytes with physiological concentrations of thyroid-stimulating hormone (TSH) has been shown to induce increased expressed of thyroglobulin and thyroid peroxidase but to simultaneously decrease expression of the TSH receptor. The reduction in TSH receptor expression by TSH is cAMP mediated. In the present study, it is demonstrated that, in thyrocytes treated with TSH, MHC class I expression decreases concomitant with the decrease in TSH receptor expression. This decreased expression is evidenced by reduced cell surface levels of MHC class I antigens, by reduced steady-state RNA levels, and by reduced transcription of the class I genes. TSH-mediated reduction of MHC class I gene transcription in FRTL-5 cells was mapped to a region within 135 base pairs of the promoter.

Animals↗
PubMed1992

Correlation between histologic diagnosis mean nucleolar organizer region count and prognosis in canine mammary tumors.

In this study, surgically excised mammary tumors from 98 bitches were graded histologically, and the grade was compared with the mean nucleolar organizer region (NOR) count in silver-stained paraffin-embedded sections. Histologically benign tumors, papillary adenocarcinomas, and intraductal carcinomas showed relatively little variation; the mean count for each category was between three and four NOR per nucleus. There was, however, a significant increase in the NOR counts in tubular and solid carcinomas. This increase was most pronounced for tumors that showed evidence of infiltration into the surrounding connective tissues. The mean NOR count for noninfiltrative carcinomas was 5.1, and that for invasive carcinomas was 7.3 (P less than 0.03). The mean NOR count for individual carcinomas ranged from 2.0 to 12.3, and a significant correlation was found between an increased NOR count and tumor-related death during the first post-surgical year. The 39 bitches in which the tumor had an NOR count less than 8.0 had a generally favorable prognosis; only six (15%) died as a result of the original neoplasm. In contrast, 18/21 dogs (85%) with a carcinoma having an NOR count greater than 8.0 died from the tumor during the first post-surgical year. A similar, although less pronounced result was obtained specifically for invasive carcinomas, in which 3/12 (25%) tumors with an NOR count less than 6.0 resulted in the death of the host, compared with 17/20 (85%) that had an NOR count greater than 6. By using this technique, it is possible to identify a subgroup of bitches with invasive mammary carcinomas that have a very poor prognosis following apparently adequate surgical ablation of the primary tumor.

Animals↗
PubMed1992

Major histocompatibility complex class I gene expression in rat thyroid cells is regulated by hormones, methimazole, and iodide as well as interferon.

Autoimmune thyroid disease is associated with enhanced expression of major histocompatibility complex class I antigens on thyrocytes. To better understand this phenomenon, we have studied the normal expression of class I genes in FRTL-5 rat thyroid cells. A variety of hormones and growth factors that regulate the growth and function of these thyroid cells were found to decrease class I RNA levels: serum, insulin or insulin-like growth factor-I (IGF-I), and hydrocortisone. Antibody preparations from Graves' patients (thyroid-stimulating antibodies), which increase cAMP levels and stimulate the thyroid, also decrease class I RNA levels. This is consistent with the fact that TSH, via its cAMP signal, reduces class I transcripts. The class I response to TSH, serum, insulin, IGF-I, or hydrocortisone is specific, in that the same agents do not similarly affect TSH receptor, thyroglobulin, thyroid peroxidase, malic enzyme, or beta-actin RNA levels. Both gamma- and alpha-interferon increase class I RNA levels in FRTL-5 cells, even in the presence of the serum, IGF-I, or hormones noted above, i.e. they overcome hormonal negative regulation in normal thyrocytes. In contrast, methimazole treatment of rat FRTL-5 thyroid cells, but not rat fibroblasts or rat FRT thyroid cells, which have no TSH receptor and no TSH-regulated function, results in reduced class I RNA levels. The action of methimazole can inhibit interferon action, is transcriptional, is duplicated by iodide, and is additive with the negative regulatory action of hormones and serum factors, including TSH.

Animals↗
PubMed1991

Modification of pain on injection of propofol--a comparison between lignocaine and procaine.

Pain on injection of propofol was assessed in a controlled, randomised study of 273 patients. They received either lignocaine 10 mg, procaine 10 mg or isotonic saline 0.5 ml, 15 seconds before the injection of propofol into a vein on the back of the hand. The incidence of pain on injection in the control group (51%) was comparable with other studies. Lignocaine and procaine both significantly reduced the pain (35% and 34% respectively, p less than 0.05) but there was no statistical difference between these two groups.

Adolescent↗
PubMed1990

Sialomucin and lytic susceptibility of rat mammary tumor ascites cells.

The potential role of cell surface sialomucin in preventing natural killer (NK)-mediated lysis of tumor cell targets has been addressed by comparing the properties of 2 NK-resistant [ascites (ASC) and short-term cultured (STC)] and 2 NK-susceptible [tunicamycin-treated (TUN) and long-term cultured (LTC)] preparations of 13762 MAT-B1 rat mammary tumor cells. Both the ASC and STC cell preparations contain elevated levels of the sialomucin ASGP-1 relative to TUN and LTC preparations as determined by [3H]glucosamine labeling and by binding of peanut agglutinin. The major difference in the susceptibility to NK-mediated lysis appeared to be due to the differences in the susceptibility to lysis by lytic granules, rather than to differences in the ability to bind or trigger effector cells, since TUN and LTC cells were approximately 10-fold more sensitive to lysis by lytic granules than were ASC and STC cells. All preparations inhibited the lysis of the susceptible target YAC-1 by normal rat splenocytes, indicating an ability to bind these effector cells. Triggering of effectors, as monitored either by incorporation of 32P into phosphatidylinositol or by transmethylation of phosphatidylcholine, was similar for the positive control YAC-1, STC, TUN, and LTC, whereas ASC appeared to be defective in triggering effectors. These results suggest that tumor sialomucin blocks the final phase of lysis, but not the initial recognition of tumor cells by NK effectors.

Adenocarcinoma↗