PubMed Health⌕ Search

Biomedical subjects

L Dutton

Publications and source records attributed to L Dutton.

7 recordsLinked to original sources
PubMed2004

Effects of chronic alcohol consumption on dermal penetration of pesticides in rats.

Topically applied ethanol is a well-known dermal penetration enhancer. The purpose of this work was to determine if ethanol consumption might also increase transdermal penetration. Male rats were fed either an ethanol containing or control diet for 6-8 wk. After the feeding regime was completed, skin was removed and placed in an in vitro diffusion system. The transdermal absorption of four very commonly used herbicides was determined. Penetration through skin from ethanol-fed rats was enhanced when compared to control by a factor of 5.3 for paraquat, 2.4 for atrazine, and 2.2 for 2,4-dichlorophenoxyacetic acid (2,4-D), and reduced by a factor 0.6 for trifluralin. Comparison of physical factors of the herbicides to the penetration enhancement revealed an inverse linear correlation with lipophilicity, as defined by log octanol/water partition coefficient (log Kow) with r2 =.98. These changes were at least partially reversible after 1 wk of abstinence from ethanol. These experiments demonstrate that regular ethanol consumption can alter the properties of the dermal barrier, leading to increased absorption of some chemicals through rat skin. If ethanol consumption has the same effect on human skin it could potentially have adverse health effects on people regularly exposed to agricultural, environmental, and industrial chemicals.

Administration, Topical↗
PubMed2000

Selective enhancement of resonance Raman spectra of separate bacteriopheophytins in Rb. sphaeroides reaction centers.

Tunable dye laser excitation of carefully prepared samples of Rb. sphaeroides reaction centers provides richly detailed resonance Raman (RR) spectra of the bacteriopheophytins, H, and the accessory bacteriochlorophylls, B. These spectra demonstrate selective enhancement of the separate bacteriopheophytins on the active (H(L)) and inactive (H(M)) sides of the reaction centers. The spectra are assigned with the aid of normal coordinate analyses using force fields previously developed for porphyrins and reduced porphyrins. Comparison of the H(L) and H(M) vibrational mode frequencies reveals evidence for greater polarization of the acetyl substituent in H(L) than H(M). This polarization is expected to make H(L) easier to reduce, thereby contributing to the directionality of electron transfer from the special pair, P. In addition, the acetyl polarization of H(L) is increased at low temperature (100 K), helping to account for the increase in electron transfer rate. The polarizing field is suggested to arise from the Mg(2+) of the neighboring accessory bacteriochlorophyll, which is 4.9 A from the acetyl O atom. The 100 K spectra show sharpening and intensification of a number of RR bands, suggesting a narrowing of the conformational distribution of chromophores, which is consistent with the reported narrowing of the distribution in electron transfer rates. Excitation at 800 nm produces high-quality RR spectra of the accessory bacteriochlorophylls, and the spectral pattern is unaltered on tuning the excitation to 810 nm in resonance with the upper exciton transition of P. Either the resonance enhancement of P is weak, or the bacteriochlorophyll RR spectra are indistinguishable for P and B.

Bacterial Proteins↗
PubMed1983

Type A behavior, self-involvement, and coronary atherosclerosis.

Prior to coronary angiography, 150 men were assessed for Type A behavior using the structured interview and two questionnaire measures. The results show no relationship between Type A behavior and extent of coronary artery disease (CAD). A second finding is that the number of self-references (I, me, my) derived from speech in the structured interview correlated positively with the number of previous myocardial infarctions and the extent of CAD; self-references correlated negatively with time on the treadmill and catheterization ejection fraction. Multiple regression analyses show self-references to remain a significant correlate of extent of disease when controlled for age, blood pressure, cholesterol, and Type A behavior.

Adult↗
PubMed1983

Patient satisfaction in adjacent family practice and non-family practice Navy outpatient clinics.

Patient satisfaction was assessed in adjacent family practice and non-family practice clinics at a Naval Regional Medical Center. Results indicated that patients in the family practice clinic (n = 341) were significantly more satisfied with care than those in the other primary care clinic (n = 390). Although older people and men were generally more satisfied with care, demographic factors did not differentially affect patient preferences for the family practice approach to ambulatory care.

Adolescent↗
PubMed1978

A circadian susceptibility/resistance rhythm for potassium cyanide in male BALB/cCr mice.

Circadian rhythms in mortality and/or survival time following a single intraperitoneal injection of a LD50 of potassium cyanide were studied. In two investigations, different but comparable subgroups of inbred male BALB/cCr mice were treated at 4-h intervals (under conditions standardized for chronobiologic study) during 24-h spans. Mice were observed for exact time-to-death during the first hour after treatment as well as overall mortality during the entire 24-h post-injection span following each KCN treatment timepoint. In both studies, mortality from KCN exhibited a 24-h rhythm. Highest mortality occurred in mice injected at 1600 (80% mortality) in Experiment 1 and 2000 (100% mortality) in Experiment II. Lowest mortality occurred at 0400 (40% mortality) in Experiment I and 0800 (30% mortality) in Experiment II. The need to consider the circadian organization of physiologic function when bioassaying toxicity is discussed.

Animals↗
PubMedDate not supplied

Sensitivity and specificity of the Papanicolaou-stained cervical smear in the diagnosis of Chlamydia trachomatis infection.

Two hundred young women had simultaneously prepared cultures for Chlamydia trachomatis and cervical smears; they also completed a questionnaire. Twelve of the chlamydial cultures were positive. There was poor correlation between the culture results and the cytologic morphology or symptoms. On initial blind reading, only 10% of the smears cytologically interpreted as positive were actually positive by culture. Under the most favorable (non-blind) interpretation, only 23% of the smears cytologically interpreted as positive for chlamydial infection were also culture positive. Because of the high incidence of false positives, we conclude that routine cytologic examination of Papanicolaou-stained smears is not an acceptable method for the diagnosis of chlamydial infections of the cervix. Immunoperoxidase staining of duplicate smears did not appear to be a successful replacement for culture.

Adult↗