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Biomedical subjects

D H White

Publications and source records attributed to D H White.

At least 73 records · Page 4Linked to original sources
PubMed1979

Nationwide residues of organochlorine compounds in starlings (Sturnus vulgaris), 1976.

Organochlorine pesticide and PCB residues in starlings from 126 sites within the contiguous 48 states were monitored during fall 1976. The average nationwide level of DDE and PCBs has increased significantly since 1974, but the number of sites reporting PCB residues has decreased fivefold. Dieldrin residues have remained unchanged since 1974. Highest DDE levels occurred in samples from parts of Arizona, Arkansas, California, Louisiana, and New Mexico.

Animals↗
PubMed1979

Nationwide residues of organochlorine compounds in wings of adult mallards and black ducks, 1976-77.

Organochlorine residues in wings of adult mallards and black ducks were monitored nationwide during the 1976-77 hunting season. DDE was found in all samples. Levels were unchanged since the 1972-73 collections in all migratory routes except the Pacific Flyway, in which residue levels declined significantly. Dieldrin levels had not changed in any flyway and residues remained low. PCB levels declined significantly in the Atlantic Flyway but remained stable in other flyways. Heptachlor epoxide, mirex, endrin, hexachlorobenzene, and chlordane isomers were detected in low amounts in some samples.

Animals↗
PubMed1978

Uptake and retention of dietary cadmium in mallard ducks.

Adult mallard ducks fed 0, 2, 20, or 200 ppm of cadmium chloride in the diet were sacrificed at 30-day intervals and tissues were analyzed for cadmium. No birds died during the study and body weights did not change. The liver and kidney accumulated the highest levels of cadmium. Tissue residues were significantly correlated in all treatment groups and residues increased with treatment level. Hematocrits and hemoglobin concentrations were normal in all groups throughout the study. Little cadmium accumulated in eggs of laying hens, but egg production was suppressed in the group fed 200 ppm.

Animals↗
PubMed1978

Effects of dietary vanadium in mallard ducks.

Acult mallard ducks fed 0, 1, 10, or 100 ppm vanadyl sulfate in the diet were sacrificed after 12 wk on treatment; tissues were analyzed for vanadium. No birds died during the study and body weights did not change. Vanadium accumulated to higher concentrations in the bone and liver than in other tissues. Concentrations in bones of hens were five times those in bones of drakes, suggesting an interaction between vanadium and calcium mobilization in laying hens. Vanadium concentrations in most tissues were significantly correlated and increased with treatment level. Lipid metabolism was altered in laying hens fed 100 ppm vanadium. Very little vanadium accumulated in the eggs of laying hens.

Animals↗
PubMed1978

Histopathologic effects of dietary cadmium on kidneys and testes of mallard ducks.

Mallard ducks fed 2, 20, or 200 ppm cadmium chloride were sacrificed at 30, 60, and 90 d. No mortality occured during the study and body weights remained unchanged. Kidney weights of the 200-ppm group were significantly greater after 60 and 90 d than those of controls; also, testis weights were significantly lower after 90 d. Kidneys of ducks fed 2 and 20 ppm cadmium were relatively unaffected; however, slight to severe kidney lesions were found in the 200-ppm group after 60 d of treatment. No significant lesions were found in mallard testes after feeding 2 ppm cadmium in the diet, and only a few birds in the 20-ppm group showed slight to moderate gonad alterations. After 90 d of treatment, however, testes of males fed 200 ppm had atrophied and the spermatogenic process had ceased. This study should provide important information for the interpretation of cadmium levels found in kidneys and testes of wild ducks.

Animals↗
PubMed1978

The usefulness of routine electrocardiographic monitoring in the EEG laboratory.

In two groups of 500 unselected general hospital patients, EKG abnormalities were found in the EEG lab in 7% and 18.6%. While the most common abnormality was premature ventricular contractions, a wide variety of serious and minor abnormalities were seen, in some instances of emergent nature. Cardiac disease was unsuspected in around 40% of these patients and confirmed in a majority of these when looked for. Depending on the EKG abnormality, hyperventilation was shown to have an adverse effect 9--50% of the time in patients with normal EKG's, it tended to produce an increase of heart rate, but this was not invariant and the change in heart rate was not related to air exchange or EEG change. It is easy for any EEG laboratory to record EKG with existing equipment, and the results of this study suggest that it should be incorporated as a routine procedure. Moreover, the data indicated that hyperventilation is not necessarily a benign procedure. It should be undertaken only after control EKG recordings and assessment of the patient's cardiac status, and performed with EKG monitoring.

Aged↗
PubMed1978

Limitations of continuous ambulatory electrocardiogram monitoring for detecting coronary artery disease.

To assess the value of continuous ambulatory electrocardiogram (ECG) monitoring for detecting coronary artery disease in symptomatic patients, we evaluated 70 patients with chest pain and normal resting ECGs prospectively by calibrated ambulatory monitoring, graded treadmill exercise, and selective coronary cineangiography. Ischemic-type ST-wave changes were detected by monitoring in 24 of the 39 patients with coronary artery disease (62% sensitivity). Twenty-six of the 39 patients had a positive treadmill (67% sensitivity). Of the 31 patients without coronary disease on angiography, 19 had negative monitoring studies (61% specificity). The treadmill was negative in 23 of these 31 patients (75% specificity). When the results of both tests were combined, 85% of the cases of coronary artery disease were detected, but only 52% of the patients without disease had negative studies. We conclude that continuous ambulatory monitoring is of limited value for detecting or excluding coronary artery disease in symptomatic patients with normal resting ECGs.

Adult↗
PubMed1977

Synthesis, antifertility activity, and protein binding affinity of 7(8 leads to 11 alpha)abeo steroids.

A series of 7(8 leads to 11 alpha)abeo steroids was synthesized by a modification of the previously described total synthesis of this class of compounds and evaluated for biological activity. In general, there was a marked reduction in the relative binding affinities of these compounds for the rabbit uterus estrogen and progestin receptor proteins. None of the compounds which were subjected to uterotropic, antiuterotropic, postcoital, progestational, antiprogestational, or antiandrogenic assays showed any significant activity.

Animals↗
PubMed1977

HLA-B7 associated tuberculin hyporesponsiveness in BCG treated melanoma patients.

Cutaneous responses to tuberculin and control antigens were measured in 24 HLA-B7 and 39 non-B7 patients before and 5-44 (average 10.5) weeks after BCG immunotherapy for malignant melanoma. Delayed tuberculin hypersensitivity increased after immunotherapy (p less than or equal 0.0001). The averaged area of induration (48 h) detected in HLA-B7 patients was half the area of induration of non-B7 patients before (p less than or equal to 0.0184) and after (p less than or equal to 0.0007) BCG treatment. Cutaneous anaphylactic hypersensitivity (0.25 h) responses to 19 of 22 antigens were significantly smaller (p less than 0.05) in HLA-B7 patients after BCG immunotherapy (p less than or equal to 0.0001). HLA-B7 patients had specific delayed cutaneous hyporesponsiveness to tuberculin and nonspecific cutaneous anaphylactic hyporesponsiveness after BCG immunotherapy.

Antibody Formation↗
PubMed1977

Nationwide residues of mercury, lead, cadmium, arsenic, and selenium in starlings, 1973.

Starlings (Sturnum vulgaris) collected in 1973 at 51 sites throughout the continental United States were analyzed for mercury, lead, cadmium, arsenic, and selenium. All samples contained detectable levels of these elements. In general, residues were low: mercury residues ranged from less than 0.01 to 0.20 ppm; lead, from less than 0.10 to 3.20 ppm; cadmium, from less than 0.05 to 0.20 ppm; arsenic, from less than 0.05 to 1.40 ppm; and selenium, from 0.10 to 1.10 ppm. There was a significant overall decline in mercury and lead residues in starlings since 1971, and a significant increase in arsenic residues. Lead residues were significantly higher in starlings from urban areas than from rural areas.

Animals↗
PubMed1976

Residues of organochlorines and heavy metals in ruddy ducks from the Delaware River, 1973.

In December 1973, eight ruddy ducks killed in an oil spill on the Delaware River were collected to be analyzed for residues of environmental pollutants. Whole carcasses were analyzed for organochlorine pesticides and livers were examined for lead, cadmium, and mercury. Residues of polychlorinated biphenyls and DDT and/or its metabolites were present in all carcasses. Dieldrin and hexachlorobenzene were present in seven of the eight samples. All livers contained detectable levels of lead, cadmium, and mercury.

Age Factors↗
PubMed1976

Nationwide residues of organochlorines in wings of adult mallards and black ducks, 1972-73.

Organochlorine residues in wings of adult mallards and black ducks were monitored during the 1972-73 hunting season. DDE, DDT, DDD, dieldrin, and polychlorinated biphenyls (PCB's) were present in all samples. Mallard wings from Alabama contained the highest mean levels of DDE, DDT, DDD, dieldrin, and PCB's. Mallards and black ducks from the Atlantic Flyway and mallards from the Pacific Flyway contained significantly lower DDE residues than in 1969-70. Black ducks from the Atlantic Flyway contained significantly less dieldrin than in 1969-70, and mallards in the Central and Pacific Flyways contained significantly lower levels of PCB's. As in 1969-70, DDE residues were lowest in the Central Flyway and highest in the Atlantic Flyway. The average PCB level remained unchanged in the Atlantic Flyway but was higher in the Mississippi Flyway than in 1969-70, probably because of the unusually high levels in Alabama samples. All organochlorine residues in black ducks from the Atlantic Flyway significantly correlated. DDE concentrations in mallards from the Atlantic Flyway significantly correlated with those of DDT, DDD, and PCB's.

Animals↗
PubMed1976

Nationwide residues of organochlorines in starlings, 1974.

Organochlorine residues in starlings (Sturnus vulgaris) from 126 collection sites were monitored during the fall of 1974. DDE, DDT, polychlorinated biphenyls (PCB's), and benzene hexachloride were present in all samples. Dieldrin, heptachlor expoxide, hexachlorobenzene, and oxychlordane were present in approximately 97% of the samples. DDE, dieldrin, and PCB residues in starlings were significantly lower than they had been in 1972.

Animals↗