Search PubMed⌕ Search

Biomedical subjects

E Moore

Publications and source records attributed to E Moore.

At least 91 records · Page 5Linked to original sources
PubMed1990

Artificial rearing of rat pups using rat milk.

The contribution of diet and surgery to the brain weight deficits observed in artificially reared rats was investigated. Four day old Long Evans rat pups were assigned to an artificially reared (AR) or mother reared (MR) group. AR pups were encannulated and fed either rat milk (AR-MOM) or replacement formula (AR-MES). MR pups received a sham encannulation (MR-SHAM) or no surgery (MR-CONT) before being returned to their dam for rearing. On day 7 all the animals were killed. Brain weights and visceral organ weights were obtained. There was no significant difference between the MR groups on any measure except stomach weights. AR-MOM pups had larger visceral organ weights than pups in the other groups. AR-MOM and AR-MES pups had similar whole brain weights, smaller than those of the MR pups. However, the cerebellar weights, and to a lesser extent, brainstem weights, showed improvements in the AR-MOM group, over the AR-MES group. Neither the effect of surgery nor of diet alone can account for the organ weight differences that have been described in AR rats. The possibility that normal growth may be primarily dependent on diet at one stage of development, with other factors gaining importance at later stages is discussed.

Animals↗
PubMed1990

Effects of lithium on an amphetamine animal model of bipolar disorder.

1. This study examines the effects of chronic lithium administration on changes induced by amphetamine administration and withdrawal on open field locomotor activity of rats, and considered as an animal model of behaviors displayed in bipolar disorders. 2. For 21 days, rats were administered either single daily intraperitoneal injections (IP) of 0.9% saline, 0.15 mEq/kg, or 1.5 mEq/kg lithium chloride (LiCl). From day 7 to day 16, half of the animals in each group consisting of 12 rats were administered twice daily IP injections of either 1.5 mg/kg d-amphetamine or 0.9% saline. From day 17 to 21, d-amphetamine was withdrawn. 3. Neither dose of LiCl significantly altered the increases in activity levels produced by amphetamine. The withdrawal of amphetamine lead to an immediate return to baseline activity levels which neither dose of LiCl significantly affected. 4. The absence of interactive effects suggests that the influence of lithium and amphetamine on activity are mediated by different neurotransmitter systems.

Animals↗
PubMed1989

Effects of lithium on appetitive discrimination in the rat.

1. The present study attempted to test the hypothesis that lithium (as chloride, 0.15 mEq/kg) promotes an attentional focus onto stimulation of high salience (Cappeliez and Moore 1988). 2. The effect of lithium treatment was studied within the context of discrimination learning in a Y-maze. 3. When the brightness cue (illuminated/dark goal arm) signalled reinforcement (food) and the spatial cue (right/left location of goal arm) acted as a distractor, lithium-treated rats showed evidence of increased readiness to focus onto the brightness cue. 4. When these experimental conditions were reversed in a second experiment, with the brightness cue now acting as a distractor, the performance of the lithium-treated rats was adversely affected. 5. These results are interpreted as supporting the hypothesis that, under the influence of this dose of lithium, rats are more likely to maintain their attention on stimulation of high salience, with accompanying reduction in the processing of peripheral stimulation. The implications of this theory for the understanding of lithium's action and manic-depressive conditions are discussed.

Animals↗
PubMed1989

Hemostatic alterations associated with phenylhydrazine-induced anemia in the rat.

Phenylhydrazine (PHZ) is a hemolytic agent which has been used in the treatment of polycythemia vera. Recent studies performed in our laboratory have indicated that the PHZ-induced anemia is immuno-hemolytic in etiology, and a prolonged bleeding time was present in some of the rats chronically treated with PHZ. The nature of this bleeding tendency was explored in the present experiment. PHZ was administered to rats once a week for a six week period. During this time, the animals were monitored for prothrombin time (PT), activated partial thromboplastin time (APTT), fibrinogen concentration, and individual coagulation factor levels as well as routine plasma chemistries and blood cell counts. In addition, radioimmunoassays (RIA) for prostacyclin, a platelet aggregation inhibitor, and prostaglandin (PG) E2 were performed. PHZ-treated animals displayed a significant elevation in both PT and APTT when compared with saline injected controls, although plasma fibrinogen levels were not appreciably altered. Further tests revealed a PHZ-induced decrease in prothrombin and factor V levels. In addition, a significant increase in plasma serum glutamate oxaloacetate transaminase (SGOT), lactate dehydrogenase (LDH), and alkaline phosphatase levels was observed as well as a diminution in cholesterol and triglycerides following PHZ administration. PHZ treatment also induced an elevation in prostacyclin levels and transient thrombocytopenia. These findings indicate that several factors may contribute to the prolonged bleeding time in PHZ-treated rats including a drug induced thrombocytopenia possibly associated with enhanced synthesis of autologous immunoglobulin G (IgG) against the senescent red cell antigen, and diminished synthesis of vitamin K-dependent coagulation factors which may be mediated by reduced vitamin K uptake by the hypo-cholesterolemic subjects.

Anemia↗
PubMed1988

Overgrowth, congenital hypotonia, nystagmus, strabismus, and mental retardation: variant of dominantly inherited Sotos sequence?

We report on 2 patients with macrocephaly, strabismus, esotropia, nystagmus, hypotonia, developmental delay, excessive size, unusual facial appearance, and improvement with age. Many of these abnormalities are present in Sotos sequence. The mothers of both patients share some characteristics with their children. These patients may represent an autosomal dominant form of Sotos sequence.

Female↗
PubMed1988

Toluene exposure during maturation of intraocular brain tissue transplants: alterations of host and graft cerebellar Purkinje neuron function and sensitivity to norepinephrine.

The effects of chronic toluene exposure on central neurons were examined using syngeneic grafts into the anterior chamber of the eye. Young adult albino rats with intraocular brain transplants inhaled toluene (1000 ppm) for 9 weeks starting at the time of transplantation, or from Week 8 to 17 after the graft was placed in oculo. Control animals were exposed to room air during the same intervals. Toluene treatment during development did not affect general growth or morphology of any of the brain areas examined. The distribution of neurofilament or glial fibrillary acidic protein immunoreactivity was similar in the experimental group and control group as well. Extracellular recordings of cerebellar Purkinje neurons showed a significantly reduced spontaneous firing rate, of 15-25%, both in intraocular transplants and in cerebellum in situ in toluene exposed animals. Postsynaptic sensitivity of intraocular and in situ Purkinje neurons to norepinephrine (NE) was evaluated. Purkinje neurons in transplants exposed to toluene during development were markedly supersensitive to superfused NE as compared to controls, while neither Purkinje neurons in mature cerebellar grafts nor cerebellum in situ showed any effects of the toluene treatment on NE sensitivity. The tissue content of NE in transplants exposed to toluene during maturation, evaluated with high-performance liquid chromatography coupled with electrochemical detection, was greater than that in the control grafts. Moreover, the content of free (3-methoxy-4-hydroxyphenyl) ethylene glycol (MHPG) was increased in both transplant and host cerebellum after toluene exposure. Taken together, these data indicate that toluene exposure during development of cerebellar grafts in oculo causes changes in postsynaptic noradrenergic sensitivity as well as decreased spontaneous activity of Purkinje neurons. Toluene exposure of adult cerebellum in situ or in oculo appears to decrease the Purkinje neuron discharge rate and increase NE turnover, but has no marked effect on postsynaptic NE sensitivity.

Administration, Inhalation↗
PubMed1988

Effects of lithium on latent inhibition in the rat.

1. A latent inhibition paradigm was used to test the proposition that lithium increases rats' capacity to ignore an irrelevant stimulation. 2. In latent inhibition, non-reinforced presentations of the stimulus in the preexposure phase are said to lead the animal to ignore this stimulus, therefore reducing its later associability with a UCS. 3. Lithium (as chloride, 0.15 mEq/kg, for 6 days) counteracted the latent inhibition and impaired the acquisition of the conditioned response in the nonpreexposed condition. These results were attributed to an increased focus on stimuli of high salience, produced by lithium. 4. This interpretation was supported in a second experiment which demonstrated that enhancing opportunities for detailed inspective exploration of the apparatus before the initiation of conditioning markedly impaired the learning of rats treated for up to 7 days with 0.15 mEq/kg lithium chloride. 5. These findings are discussed within the context of the hypothesis that lithium narrows the breadth of attention onto stimuli of high salience at the expense of the processing of stimuli of low salience.

Animals↗
PubMed1988

Pneumoconiosis in iron ore surface mining in Labrador.

A cross-sectional survey of the work force at an iron ore surface mine and beneficiation plant in Labrador identified cases with a radiologic diagnosis compatible with simple pneumoconiosis by the International Labour Organization (ILO) classification (1980). Their distribution by ILO categories 1, 2, and 3, after excluding those with confounding diagnoses for pneumoconiosis, was 30, 10, and 2 cases, respectively. ILO category was related to age, duration of current employment, and cumulative respirable dust and quartz levels, as well as to decrement in ventilatory function.

Adult↗
PubMed1987

Influence of the extent of resection on survival after curative treatment of gastric carcinoma. A retrospective multivariate analysis.

The therapeutic value of extensive gastric resection and regional lymphadenectomy in the curative treatment of gastric adenocarcinoma is controversial. We undertook a retrospective study of 210 patients treated with curative intent from 1960 to 1980. A multivariate survival analysis using the Cox model revealed five significant variables predictive of death from gastric cancer--two inherent pathologic factors: (1) nonpyloric site and (2) metastases in more than three lymph nodes, and three treatment factors that could often be controlled by the surgeon: (3) microscopic positive gastric resection margin, (4) inadequate lymphadenectomy, and (5) total gastrectomy. These observations reaffirm the value of wide gastric resection and adequate lymphadenectomy but argue against a general policy of elective total gastrectomy in the curative treatment of gastric carcinoma.

Adenocarcinoma↗
PubMed1987

Sarcocystis mucosa (Blanchard 1885) Labbé 1889 in unadorned rock wallabies (Petrogale assimilis) and Bennett's wallabies (Macropus rufogriseus).

Macroscopic cysts of a protozoan parasite were detected in the gastro-intestinal walls of two unadorned rock wallabies (Petrogale assimilis) and 20 Bennett's wallabies (Macropus rufogriseus). The cysts were located predominantly in the muscularis externa and the submucosa of the forestomach, small intestine and colon and sometimes in the muscularis externa of the oesophagus and caecum. All cysts exhibited similar morphological and ultrastructural characteristics. They were bounded by thick primary cyst walls (containing distinctive bulbous-like protrusions) and were surrounded by collagen fibres and host connective tissue cells (mainly fibrocytes). The cysts were divided by septae into internal compartments containing metrocytes and cystozoites. The cystozoites contained numerous organelles typical of apicomplexan protozoan parasites (including an apical complex, a micropore, rhoptries, micronemes, polysaccharide granules and 22 subpellicular microtubules) and they were observed to divide by the process of endodyogeny. Despite the unusual location of the cysts, they were classified on the basis of their ultrastructural characteristics as Sarcocystis mucosa (Blanchard 1885) Labbé 1889.

Animals↗
PubMed1987

Coccidia in sheep in South Australia.

Faecal samples from 136 sheep from four different locations in South Australia were examined to determine the types and numbers of Eimeria spp. present. Coccidian oocysts were detected in 80% of the sheep and 11 different species of Eimeria were identified. The species detected (and their prevalence) were E. crandallis/E. weybridgensis (76%), E. ovina (55%), E. ovinoidalis (54%), E. granulosa (49%), E. parva/E. pallida (44%), E. intricata (37%), E. ahsata (31%), E. faurei (24%), and E. punctata (1%). No major differences were observed in the patterns of infection between the four locations examined. Faecal samples were also collected each month for a year from 48 lambs at two of the locations and oocyst counts were found to decrease markedly in all lambs after 6 months of age but to persist at low levels until the end of sampling at 17 months of age.

Age Factors↗
PubMed1987

Size distribution of airborne dust in Labrador iron mines.

The size distribution of the total airborne dust and its components approximates a straight line on a plot of log mass undersize against log aerodynamic size. The quartz component distribution has a reasonably constant slope, is close to the distributions found in other mines and mills, and follows the normal breakage laws. The results for the iron component suggest that the top size present is similar to that of quartz and that the slope is also similar. The slopes for total dust by weight are not as steep as for quartz and suggest a bimodal distribution consisting of a coarser mineral fraction mixed with a finer fraction from other sources, such as combustion products, that are often found. The slopes for manganese are sometimes much less than for iron or quartz and suggest that manganese is associated with a more crushable rock. The one finding of chromium suggests that it is associated mostly with very fine particles and, therefore, may have been dispersed as fume from an operation such as welding.

Air Pollutants, Occupational↗
PubMed1987

Comparison of dust samplers: statistical analysis techniques.

Statistical analyses comparing pairs of dust samplers were carried out using five models, a straight line through the origin, linear with intercepts, logarithmic, a logarithmic (weight + constant), and a fifth forced through the origin. The fourth and fifth models combined the arithmetic portion of the error, associated with weighing and handling, with the geometric portion, associated with sampling and the dust cloud variations, into a unified geometric form. It was shown that some of the assumptions on which the least squares method of regression analysis are based were not met and that corrections had to be made. In most cases no significant difference was found between the corrected regression lines and the expected physical relation, a straight line through the origin. In the exceptions physical reasons were found to support the nonlinearity found in statistical analysis. It is suggested that the best estimate of the relation between two dust samplers can be obtained by a least squares determination of the straight line through the origin using transformed variables. A method is given for determining values of the constants. The application of this statistical method to comparisons between dust samplers not measuring the same parameter of the dust cloud is discussed with an example. The considerations in assessing historical dust measurements are outlined.

Air Pollutants↗
PubMed1987

Comparison of respirable dust samplers for use in hard rock mines.

Five respirable dust size selectors and eleven filter holders were compared, some at two flow rates. These included horizontal elutriators, impactors, metal cyclones and nylon cyclones. The comparisons were carried out both in the laboratory and in mines. The respirable dust on the filters was assessed by weighing, and where relevant, by X-ray diffraction for quartz with the use of a direct-on-filter method. The results obtained showed that the relation between most pairs of samplers could be represented by a straight line through the origin and that the personal samplers collecting more dust--the CAMPEDS impactor and the B.C.I.R.A. cyclone--gave higher reproducibility in the low dust concentrations found in many hard rock mines. The samplers based on the nylon cyclone were less suitable for hard rock mines containing a substantial proportion of quartz, though satisfactory in coal mines with their higher dust control standards.

Air Pollutants↗