Biomedical subjects

E A Boyle

Publications and source records attributed to E A Boyle.

15 recordsLinked to original sources

PubMed2001

Physicochemical and microbiological properties of selected rice flour-based batters for fried chicken drumsticks.

Rice flour-based batter (RFBB) formulations for chicken drumstick coating were developed as an alternative for traditional wheat flour-based batter (WFBB). Physicochemical properties and storage stability of selected RFBB were evaluated and compared to WFBB. Batter pickup of RFBB formulated in combination with oxidized corn starch and methylcellulose (MC) was not significantly different from that of WFBB. In contrast, batters with only rice and corn flour (60:40% flour weight) exhibited significantly higher pickup. Rice flour batter with 15% oxidized corn starch had the lowest batter pickup. All RFBB exhibited (P < 0.05) lower oil absorption than WFBB. The TBA values of RFBB and WFBB increased (P < 0.05) with increased frozen storage time at -40 C for 90 d. The RFBB with MC exhibited the lowest TBA values, whereas WFBB had the highest values. Microstructural analysis revealed that freezing caused structural deterioration of all batters, but the RFBB with MC exhibited less freezing tolerance than other samples. The total plate counts of immediately fried or frozen fried chicken stored for 90 d were less than 1 log cfu/g sample. The RFBB with 5% oxidized corn starch and MC can replace WFBB on fried drumsticks. Additionally, RFBB results in a healthier product due to lower fat absorption.

Absorption↗

PubMed2000

Glacial/interglacial variations in atmospheric carbon dioxide.

Twenty years ago, measurements on ice cores showed that the concentration of carbon dioxide in the atmosphere was lower during ice ages than it is today. As yet, there is no broadly accepted explanation for this difference. Current investigations focus on the ocean's 'biological pump', the sequestration of carbon in the ocean interior by the rain of organic carbon out of the surface ocean, and its effect on the burial of calcium carbonate in marine sediments. Some researchers surmise that the whole-ocean reservoir of algal nutrients was larger during glacial times, strengthening the biological pump at low latitudes, where these nutrients are currently limiting. Others propose that the biological pump was more efficient during glacial times because of more complete utilization of nutrients at high latitudes, where much of the nutrient supply currently goes unused. We present a version of the latter hypothesis that focuses on the open ocean surrounding Antarctica, involving both the biology and physics of that region.

Animals↗

PubMed2000

Phosphate depletion in the western North Atlantic Ocean.

Surface waters of the subtropical Sargasso Sea contain dissolved inorganic phosphate (DIP) concentrations of 0.2 to 1.0 nanomolar, which are sufficiently low to result in phosphorus control of primary production. The DIP concentrations in this area (which receives high inputs of iron-rich dust from arid regions of North Africa) are one to two orders of magnitude lower than surface levels in the North Pacific (where eolian iron inputs are much lower and water column denitrification is much more substantial). These data indicate a severe relative phosphorus depletion in the Atlantic. We hypothesize that nitrogen versus phosphorus limitation of primary production in the present-day ocean may be closely linked to iron supply through control of dinitrogen (N2) fixation, an iron-intensive metabolic process. Although the oceanic phosphorus inventory may set the upper limit for the total amount of organic matter produced in the ocean over geological time scales, at any instant in geological time, oceanic primary production may fall below this limit because of a persistent insufficient iron supply. By controlling N2 fixation, iron may control not only nitrogen versus phosphorus limitation but also carbon fixation and export stoichiometry and hence biological sequestration of atmospheric carbon dioxide.

Atlantic Ocean↗

PubMed2000

Detecting holocene changes in thermohaline circulation.

Throughout the last glacial cycle, reorganizations of deep ocean water masses were coincident with rapid millennial-scale changes in climate. Climate changes have been less severe during the present interglacial, but evidence for concurrent deep ocean circulation change is ambiguous.

Animals↗

PubMed1997

Characteristics of the deep ocean carbon system during the past 150,000 years: SigmaCO2 distributions, deep water flow patterns, and abrupt climate change.

Studies of carbon isotopes and cadmium in bottom-dwelling foraminifera from ocean sediment cores have advanced our knowledge of ocean chemical distributions during the late Pleistocene. Last Glacial Maximum data are consistent with a persistent high-SigmaCO2 state for eastern Pacific deep water. Both tracers indicate that the mid-depth North and tropical Atlantic Ocean almost always has lower SigmaCO2 levels than those in the Pacific. Upper waters of the Last Glacial Maximum Atlantic are more SigmaCO2-depleted and deep waters are SigmaCO2-enriched compared with the waters of the present. In the northern Indian Ocean, delta13C and Cd data are consistent with upper water SigmaCO2 depletion relative to the present. There is no evident proximate source of this SigmaCO2-depleted water, so I suggest that SigmaCO2-depleted North Atlantic intermediate/deep water turns northward around the southern tip of Africa and moves toward the equator as a western boundary current. At long periods (>15,000 years), Milankovitch cycle variability is evident in paleochemical time series. But rapid millennial-scale variability can be seen in cores from high accumulation rate series. Atlantic deep water chemical properties are seen to change in as little as a few hundred years or less. An extraordinary new 52.7-m-long core from the Bermuda Rise contains a faithful record of climate variability with century-scale resolution. Sediment composition can be linked in detail with the isotope stage 3 interstadials recorded in Greenland ice cores. This new record shows at least 12 major climate fluctuations within marine isotope stage 5 (about 70,000-130,000 years before the present).

Journal Article↗

PubMed1994

The antiemetic activity of granisetron against cytostatic-treatment-induced emesis in 10- to 13-week-old ferrets.

The antiemetic activity of granisetron was examined in ferrets aged 10-13 weeks. Emesis was induced by exposure to either whole-body X-irradiation (50 Gy over 10.4 min) or cyclophosphamide (80 mg/kg i.v.) plus doxorubicin (6 mg/kg i.v.). Following exposure to whole-body X-irradiation, the young ferrets vomited with a similar latency to vomit and severity of emesis to that shown by adult animals. Granisetron (0.5 mg/kg i.v.) significantly reduced (P < or = 0.05) the number of vomits and retches and two out of four animals were completely protected. Following injection of cyclophosphamide and doxorubicin, the young ferrets showed a reduced emetic response compared to adult animals. Following a dose of granisetron (0.5 mg/kg i.v.), only one out of four ferrets vomited compared to four out of four in the control group. Further experiments showed that cisplatin (12.5 mg/kg i.v.) was unable to induce vomiting in the young ferret (n = 2). Granisetron (0.5 mg/kg i.v.) was well tolerated by the young ferret and was able to reduce significantly or completely abolish emesis induced by cytostatic treatment. The data support the use of granisetron in pediatric patients and clinical trials are currently underway in this patient population.

Aging↗

PubMed1994

Further studies of the antiemetic activity of granisetron against whole body X-irradiation or cisplatin-induced emesis in the ferret.

In ferrets, the highly selective 5-HT3 receptor antagonist, granisetron, abolished or reduced emesis induced by cisplatin (10 mg/kg i.v.) or whole body X-irradiation (50 Gy in 10.4 min) in a dose-dependent manner when administered by a variety of routes (intravenous, per os, subcutaneous, intramuscular). Complete protection from vomiting and retching was achieved with 0.5 mg/kg i.v. or p.o. granisetron. Granisetron (0.5 mg/kg i.v.) was also effective when given 6 h before cisplatin, completely protecting 50% of ferrets for a total of 10 h. Following repeat dosing, for either 4 days i.v. or 10 days p.o. before emetic challenge, granisetron (0.5 mg/kg) still retained its antiemetic activity on the 5th or 11th day. Prior treatment with cyclophosphamide (80 mg/kg i.v.) resulted in a significantly shorter time to the onset of vomiting after exposure to X-irradiation. Granisetron, but not saline, abolished vomiting and nausea when given as intervention after this combined emetic regimen. These results show that granisetron has potential flexibility for administration via a variety of different routes and also a long duration of action when used as an antiemetic against a wide range of cytostatic agents.

Animals↗

PubMed1991

Empirical support for psychological profiles observed in multiple sclerosis.

Though increasing attention is being paid to psychological aspects of multiple sclerosis, much research continues to examine patients as differing in quantity rather than quality of psychological abnormality or response. Cluster analysis was used to identify distinctive psychological profiles in a large sample of patients with multiple sclerosis. It employed three measures, carefully chosen to capture the main responses historically observed in multiple sclerosis. These measures were (1) the patient's physical disability-impairment, assessed by a neurologist; (2) physical disability-impairment as perceived and reported by the patient; and (3) self-reported psychological well-being (or distress) independent of physical signs and symptoms. The optimal solution from the cluster analysis separated the 99 patients into 10 clusters, which were collapsed into four profiles, consistent with the labels "depression," "denial," "exaggerated somatic," and "severity-related." These data give strong empirical support to the existence of discrete and distinctive coping styles in multiple sclerosis.

Adult↗

PubMed1990

Cellular immune response in multiple sclerosis plaques.

Multiple sclerosis plaques were immunohistochemically stained to exhibit cells expressing immune-system antigens. Human leukocyte antigen (HLA)-DR-positive cells formed dense rings around all plaque regions. The majority were reactive microglia/macrophages. Counterstaining with oil red O revealed heavy myelin debris within these cells. They were distinct from astrocytes, which were identified with an antibody to glial fibrillary acidic protein (GFAP) and which did not contain oil red O myelin debris. Numerous leukocytes and microglia were stained with antibody to leukocyte common antigen (LCA). Lymphocytes in cuffs around vessels, along the margins of capillary walls, and, sparingly, in the tissue matrix of affected areas, were stained with antibodies to CD4 (T-helper/inducer) and CD8 (T-cytotoxic/suppressor). In experimental allergic encephalomyelitis (EAE) induced in Lewis rats, a similar proliferation of Ia-positive (OX6, OX17) cells displaying reactive microglia/macrophage morphology was observed. These Ia-positive cells also were easily distinguished from GFAP-positive astrocytes. The results suggest that macrophages/reactive microglia, and not astrocytes, express class II MHC antigens in multiple sclerosis and EAE plaques.

Animals↗

PubMed1988

The anti-emetic potential of the 5-hydroxytryptamine3 receptor antagonist BRL 43694.

In ferrets, the selective 5-hydroxytryptamine (5-HT) 5-HT3 receptor antagonist BRL 43694 given as a single injection (0.05-0.5 mg kg-1 i.v.) before cisplatin, or by divided dose (2 x 0.005-2 x 0.5 mg kg-1 i.v.) before and after cisplatin dramatically reduced or abolished the severe cisplatin-induced vomiting. BRL 43694 also substantially reduced the vomiting induced by cyclophosphamide:doxorubicin, and prevented the trimelamol-induced emesis. The severe emesis caused by whole body exposure to X-irradiation was prevented by intravenous or oral BRL 43694. A single i.v. dose of BRL 43694 given during an emetic episode or within the peak emetic period, abolished the vomiting induced by the cytotoxic drugs and by X-irradiation, usually within 30 s. Where the induction of emesis was prevented or subsequently abolished by BRL 43694, the associated behaviour (subjectively assessed as nausea) was also absent or greatly attenuated. BRL 43694 (0.1 mg kg-1 i.v.) did not affect the emesis evoked in dogs by the dopamine agonist apomorphine. The potent anti-emetic activity of BRL 43694 is discussed in terms of potential clinical use, and of the fundamental role that 5-HT3 receptors may play in the mechanisms of nausea and vomiting.

Animals↗

PubMed1987

Inhibition of arachidonic acid-induced ear oedema as a model for assessing topical anti-inflammatory compounds.

We have found that mouse ear oedema induced by the topical application of arachidonic acid is not a specific screen for compounds inhibiting the lipoxygenase or cyclo-oxygenase pathways of arachidonic acid metabolism. Although such compounds are able to reduce the oedema substantially, pharmacological agents such as histamine antagonists, phosphodiesterase inhibitors, free radical scavengers, and also various compounds not normally considered to have anti-inflammatory properties, can equally effectively reduce the oedema. A mutual potentiation of the effects of prostaglandins, leukotrienes and mast cell-derived histamine would allow many, but not all, of the active agents to be rationalised. The ability of compounds not influencing these three types of inflammatory mediators to reduce the oedematous response means the model is of limited value for directed screening.

Animals↗

PubMed1986

7-Aroyl-2,3-dihydrobenzo[b]furan-3-carboxylic acids and 7-benzoyl-2,3-dihydrobenzo[b]thiophene-3-carboxylic acids as analgesic agents.

The synthesis of a series of 7-aroyl-2,3-dihydrobenzo[b]furan-3-carboxylic acids and 7-benzoyl-2,3-dihydrobenzo[b]thiophene-3-carboxylic acids is described. The isomeric 4-benzoyl-1,3-dihydrobenzo[c]furan-1-carboxylic acid was also prepared. Compounds were evaluated for analgesic activity in the mouse phenyl-p-quinone-induced writhing test. Selected compounds were tested for their ability to produce gastric damage in fasted mice and for inhibition of prostaglandin synthetase activity in vitro. Zomepirac was used as a reference. Structure-activity relationships are discussed. One of the compounds, 7-benzoyl-5-chloro-2,3-dihydrobenzo[b]furan-3-carboxylic acid (2c), combined potent analgesic activity with low gastric irritancy.

Analgesics↗

PubMed1984

BRL 20459, a novel topically active non-steroidal anti-inflammatory drug.

BRL 20459 is a novel compound which displays anti-inflammatory activity when applied topically in the croton oil and cantharadin rat ear inflammation models. The compound does not inhibit uv-induced erythema in the guinea-pig or granuloma formation in the cotton pellet test in the rat. BRL 20459 does not inhibit prostaglandin synthesis nor does it interact with corticosteroid receptors in the thymus. In contrast to hydrocortisone, BRL 20459 did not cause thymus involution or reduce body weight gain in rats. BRL 20459 would seem to have a different mechanism of action to hydrocortisone, but this mechanism is as yet unknown.

Administration, Topical↗

PubMed1982

Nabumetone (BRL 14777, 4-[6-methoxy-2-naphthyl]-butan-2-one): a new anti-inflammatory agent.

Nabumetone is a compound of novel structure which displays acute anti-inflammatory activity in the carrageenan-induced oedema model in rats and the ultraviolet-induced erythema model in guinea-pigs. Its activity in these tests is greater than that of aspirin but less than that of naproxen and indomethacin. In the cotton pellet-induced granuloma model in the rat, the compound is active and produces no signs of toxicity at doses much greater than the lowest effective dose, unlike aspirin, naproxen or indomethacin. Nabumetone is also active in the adjuvant-induced arthritis test in rats. In contrast to aspirin, indomethacin and naproxen, the compound is well tolerated by the stomach of fasted rats at doses in excess of those with anti-inflammatory activity. These findings could be linked to the relatively poor ability of nabumetone to inhibit the synthesis of prostaglandins in vitro and to its non-acidic structure. The compound has greater mild analgesic activity than paracetamol, is equi-active with phenylbutazone, but less active than aspirin, naproxen and indomethacin. Nabumetone also has antipyretic activity in the rabbit. No interactions with the hypothalamic-pituitary-adrenal axis have been found.

Analgesics↗

PubMed1982

The effect of a novel, non-steroidal anti-inflammatory compound, nabumetone (BRL 14777), on cellular infiltration into 24-hour polyvinyl sponge implants in the rat, compared with some steroidal and non-steroidal anti-inflammatory drugs.

The time-course of cell migration into saline-soaked sponge implants over 5 days showed peak polymorphonuclear leucocyte (PMNL) infiltration at 24 h. In common with the corticosteroids dexamethasone and hydrocortisone, and the non-steroidal anti-inflammatory drugs indomethacin, (+)-naproxen, BW 755C and benoxaprofen, nabumetone decreased cell migration into the sponges. PMNLs and mononuclear cells were reduced at 24 h, and there was a parallel decrease in exudate levels of the lysosomal acid hydrolase beta-N-acetyl glucosaminidase [NAG ECB, 3, 2, 1, 30]. Impregnation of sponges with lambda-carrageenan (1%) caused a 2-3 fold increase in cell numbers, with a relatively greater proportion of PMNLs; drug effects were more marked in these implants.

Animals↗