Search PubMed⌕ Search

Biomedical subjects

D Moran

Publications and source records attributed to D Moran.

At least 73 records · Page 4Linked to original sources
PubMed1985

Strong cash flow, balance sheet, management, key to capital needs. Symposium on Healthcare Directions: the capital financing imperative.

For a full day, 10 individuals representing varied health fields and viewpoints within the healthcare industry discussed a number of topics confronting health care and predicted what the environment is likely to be in three years (see accompanying sidebars for symposium participants and purpose). This article focuses on one of the symposium topics, capital availability and financing, and the implications in a time of declining utilization.

Capital Financing↗
PubMed1984

Fluorescent localization of calcium at sites of cell attachment and spreading.

Chlorotetracycline (CTC), a calcium-chelating fluorescent probe identifies and localizes calcium when applied to cultured neural crest cells. The fluorescence occurs at specific membrane regions involved in cell attachment and spreading as well as with the formation of cytoskeletal stress fibers (actin microfilament bundles). The observed CTC reaction indicates that calcium sequestration and the development of these membrane-cytoskeletal features share a temporal and spatial pattern. Thus, the selective availability of calcium may be an important determinant of cell morphogenesis.

Ambystoma↗
PubMed1983

The use of chlorotetracycline to localize calcium in neural crest cells.

Cultured amphibian neural crest cells in the early phases of migration (1-2 days) extend broad, clear cytoplasmic processes known as lobopodia. These regions exhibit rapid changes in the contraction-relaxation cycle and in substratum adhesion. Because of the putative role of Ca2+ in both cytoskeletal function and cell attachment, its distribution in these cells was studied. Chlorotetracycline (CTC), the Ca2+-chelating fluorescent probe, was used to investigate whether there is a temporal and spatial localization of Ca2+ in cell regions concerned with movement and attachment. Differentiated neural crest cells (7 days), which contain an abundance of actin stress fibers, were also studied to determine whether these cytoskeletal elements were associated with Ca2+. The results with CTC indicate that in early migratory cells regions of membrane extension and protrusion contain higher levels of Ca2+ and that the actin stress fiber system of differentiating neural crest cells (7 days) is associated with Ca2+. It was determined that using the CTC in the fixative produced the same labeling profile as when live cells were labeled with the CTC. Use of CTC in the fixative is a decided advantage over treatment of cells with CTC while alive since it avoids the photooxidative damage which normally accompanies fluorescent observations of CTC on living cells.

Actins↗
PubMed1982

Pesticides in groundwater: the aldicarb story in Suffolk County, NY.

Aldicarb, a carbamate pesticide, was detected for the first time in groundwater in Suffolk County, New York, in August 1979. Although all laboratory and field studies indicated that the pesticide could not reach groundwater, a combination of circumstances allowed its residues not only to reach groundwater but also to be ingested by humans. Inquiries in hospitals and poison control centers did not reveal any cases of carbamate poisoning. The extensive monitoring program, conducted by the County in cooperation with the federal and state agencies and the Union Carbide Corporation, showed that 1,121 (13.5 per cent) of the 8,404 wells examined exceeded the state recommended guidelines of 7 ppb. Of the contaminated wells 52 per cent contained adicarb between 8 and 30 ppb, 32 per cent between 31 and 75 ppb, and 16 per cent more that 75 ppb. Residents whose wells exceeded the guideline were advised not to use the water for drinking or cooking purposes and to obtain an alternate source of potable water. The Union Carbide Corporation provided those residents with activated carbon filtration units. The incident raises several serious issues, such as the testing of pesticides under field conditions prior to registration and during their use, the validity of the recommended actionable levels, and the paucity of long-term epidemiologic studies of the health effects resulting from consumption of pesticides in trace concentrations.

Aldicarb↗
PubMed1981

Cataract--the ultraviolet risk factor.

Ophthalmic examination of 64 307 Aborigines and 41 254 non-Aborigines in remote rural Australia during the course of the National Trachoma and Eye Health Program revealed a positive correlation between the prevalence of senile cataract and levels of climatic ultraviolet (UV) radiation. Aborigines were more likely to be affected by senile cataract than non-Aborigines. It seems that Aborigines who live in areas of higher UV irradiation are more likely to acquire cataract; more likely to acquire the condition earlier in life; and more likely to be blind or visually disabled by it, than their counterparts living in areas of low UV irradiation. Provision of adequate shelter in areas of high insolation, where most cases of cataract occur, is likely to be an effective preventive measure.

Adult↗
PubMed1981

Fluorescent observations on the stress fiber system of neural crest cells after con A treatment. A simple, quick, fluorescent method.

Concanavalin A (Con A), 25 microgram/ml in the tetrameric form, inhibits migration and differentiation of cultured amphibian neural crest. Affected cells loose their angulated morphology and become rounded. A correlation exists between the lectin treatment and the overall cellular and stress fiber morphology. We describe a quick, simple method for disclosing the stress fiber system using fluorescence microscopy after staining with 1% alcoholic eosin.

Ambystoma↗
PubMed1981

Clinical and immunologic evaluation of glutaraldehyde-modified tyrosine-adsorbed short ragweed extract: a double-blind, placebo-controlled trial.

Glutaraldehyde-modified, tyrosine-adsorbed ragweed extract (GTR) is a modification of allergen extract to reduce allergenicity but retain immunogenicity. We evaluated the clinical efficacy and immunologic changes associated with the administration of GTR (16,350 protein nitrogen units) or placebo to a group of 100 atopic subjects with ragweed hay fever. The study was carried out in a double-blind, placebo-controlled fashion. Clinical response was measured by daily symptom diaries. physician evaluations, and patient responses. Changes in ragweed-specific IgE and IgG antibody were evaluated with an amplified enzyme-linked immunosorbent assay (alpha-ELISA) and were compared with measurements by RAST and a protein A-binding assay for IgG antibody. Treatment with GTR resulted in a sixfold increase in blocking IgG antibody and a small increase in IgE-specific antibody. No changes occurred in the placebo treated group. Mild immediate local reactions occurred after 74% of injections, and late-onset local reactions occurred after 62% of injections in the treated group. The placebo-treated group experienced immediate or late local reaction after only 12% of injections. There were two mild late-onset urticarial reactions of a generalized nature in the treatment group. The treatment group experienced significantly fewer symptoms than the placebo group throughout the season (p less than 0.02), although the difference was not dramatic. The results showed that GTR could be safely given in five preseasonal injections, with retained immunogenicity but less potential for generalized reactions. GTR is an improved method of allergy immunotherapy with the potential for clinical benefit when used in a brief preseasonal treatment regimen.

Aldehydes↗
PubMed1981

Nitrite stability and nitrosation potential in human gastric juice.

Human gastric juice samples were investigated from high- and low-risk areas (Colombia and Boston) for factors which influence the stability of nitrite and its potential for nitrosamine formation. The samples from individuals with chronic atrophic gastritis and intestinal metaplasia were not reactive to nitrite and supported a rate of nitrosation largely compatible with the nitrite and thiocyanate concentration. The samples from other individuals contained factors which destroyed nitrite and inhibited nitrosation. There were several samples from both groups which had an elevated rate of nitrosation catalyzed by unknown factors. It is suggested that continued hypochlorhydria might deplete gastric juice of its natural protective factors and lead to an elevated risk of gastric cancer in agreement with our earlier etiological model [1].

Colombia↗
PubMed1979

Gastric cancer in Colombia. IV. Nitrite and other ions in gastric contents of residents from a high-risk region.

Samples of gastric contents from 2 groups of patients from a region of high risk for gastric cancer were analyzed for pH, nitrite, nitrate, thiocyanate, and chloride. In each group, the patients could be divided into 2 subgroups: those with a gastric pH of less than 5 and those with a gastric pH of greater than 5. Above pH 5, nitrite was correlated with nitrate. The pH greater than 5 subgroups had significantly higher (P less than 0.01) nitrite content (20- to 100-fold). Some high- and low-nitrite samples were also analyzed for macro and trace metal ions, but differences were not significant. This is the first report in which patients with diagnosed gastric pathology related to a precancerous state were shown to have high levels of a putative carcinogen precursor. The results were compatible with our original hypothesis of intragastric nitrite formation by bacterial reduction of nitrate and concomitant synthesis of carcinogenic N-nitroso compounds.

Aged↗
PubMed1977

Pseudoexfoliation of the lens in Australian Aborigines.

The first cases of pseudoexfoliation of the lens to be found in Australian Aborigines are reported. The prevalence rate in the communities in central Australia is 1-3% and for those 61 years and older is 16-3%. Within the limits of our assessment glaucoma was an associated finding in 8-1% of these cases. A high incidence of old trachoma, previous trauma, and Labrador keratopathy was also noted in these people.

Adult↗
PubMed1975

An ultrastructural examination of the role of cell membrane surface coat material during neurulation.

Data from neural crest cultures indicate that cell surface coat material (CSM) is directly involved in cellular migration and events surrounding differentiation. To investigate whether the CSM also has a morphogenetic role, embryos of the amphibian Ambystoma maculatum were examined ultrastructurally throughout the stages of neurulation. Segments of the neural axis were fixed in glutaraldehyde-containing Alcian blue 8GX, which reportedly enhances preservation of CSM, and were postfixed in OsO4 containing 1 percent lanthanum nitrate, which stains the CSM. The medial groove formed by the appearance of the neural ridges contains a large amount of CSM and numerous vesicles coated with lanthanum-positive material. In contrast, the lateral ridge surfaces are covered by a small amount of uniformly distributed CSM and a paucity of vesicles. As the ridges begin to fold there is a progressive increase in the amount of CSM within the presumptive neural tube region. Further convergence of the neural folds is accompanied by an increase of CSM at their leading edges. As the folds approximate each other, lanthanum-positive material physically bridges the gap. However, as the apposing tissue actually abuts to form the neural tube, no CSM is observed in the remaining interspace. The specific distribution and sequential accumulation of cell CSM during the events of neurulation strongly suggest its direct participation in the morphogenetic process.

Ambystoma↗