Inactivation of human alpha-1-proteinase inhibitor by gas-phase cigarette smoke.

Direct exposure of human alpha-1-proteinase inhibitor to the gas-phase smoke from one cigarette results in an initial rapid loss of elastase inhibitory capacity, the amount of which is dependent upon the age of the smoke. This short-term inactivation is not seen when the protein is exposed to aqueous extracts of cigarette smoke (as had been done in the past). Both exposure regimens result in a slow inactivation occurring over several days.

Long-term incompatible kidney survival in outbred higher primates without chronic immunosuppression.

Transplantation between non-identical humans has been limited by the requirement for chronic immunosuppression (CI). This study demonstrates in a nonhuman primate model that long-term acceptance of incompatible kidney allografts can be achieved without the use of CI. Following incompatible kidney transplantation, rhesus monkey recipients were given a 5-day course of clinical rabbit antithymocyte globulin (RATG).

Thigh compartment syndrome without lower extremity trauma following application of pneumatic antishock trousers.

Reported are two cases of thigh compartment syndrome following application of a pneumatic antishock trouser suit. Both patients developed compartment syndromes after prolonged antishock suit use in the absence of any apparent leg trauma. We recommend that suit compartment pressures be no more than required to restore adequate blood pressure.

The radicals in cigarette tar: their nature and suggested physiological implications.

The paramagnetism of cigarette tar is found to be associated with at least four different types of species. One of the types is responsible for over 80 percent of the total paramagnetism and has a signal intensity that is independent of temperature from 60 to 250 K. This non-Curie-Weiss temperature dependence indicates that the principal paramagnetic species in tar is not an organic monoradical (doublet) species but instead is a donor-acceptor excimer with a paramagnetic excited state and a diamagnetic ground state.

Transitional blood flow zones between ischemic and nonischemic myocardium in the awake dog. Analysis based on distribution of the intramural vasculature.

The present study evaluates the transitional or border zone of intermediate blood flow reduction between nonischemic and ischemic regions after acute coronary artery occlusion in chronically instrumented dogs, using methods that minimize an admixture of ischemic and nonischemic myocardium in the tissue analyzed. The regions perfused by occluded and nonoccluded vessels were identified by tracing the extra and intramural distribution of the coronary vasculature from postmortem angiograms. Regional blood flow was evaluated in serial 3-mm-wide epicardial and endocardial zones from outside and inside the interface between occluded and nonoccluded vessels.

Electron-spin resonance study of mainstream and sidestream cigarette smoke: nature of the free radicals in gas-phase smoke and in cigarette tar.

Radicals in the gas phase of both mainstream and sidestream cigarette smoke have been studied using electron-spin resonance ESR spin-trapping techniques with alpha-phenyl-N-tert-butyl nitrone (PBN) as the spin trap. The principal radicals we trap appear to be alkoxyl radicals. Mainstream and sidestream gas-phase smoke each have about the same concentration of radicals, about 1 X 10(16) radicals per cigarette (or 5 X 10(14) per puff).

The role of superoxide in xanthine oxidase-induced autooxidation of linoleic acid.

The effect of hydroxyperoxyoctadecadienoic acid, e.g. 13-hydroperoxy-cis,9,trans-11-octadecadienoic acid, on the autooxidation of linoleic acid induced by superoxide radical was examined in a system containing xanthine oxidase, acetaldehyde, and diethylenetriaminepentaacetic acid dissolved in an aqueous phosphate buffer containing 10% ethanol.

Mechanisms of nitrogen dioxide reactions: initiation of lipid peroxidation and the production of nitrous Acid.

The reactions of nitrogen dioxide with cyclohexene have been studied as a model for the reactions that occur between nitrogen dioxide in smoggy air and unsaturated fatty acids in pulmonary lipids. As predicted from earlier studies at high nitrogen dioxide concentrations, this gas reacts with cyclohexene predominantly by addition to the double bond at nitrogen dioxide concentrations of 1 percent (10,000 parts per million) to 40 percent in nitrogen; in the presence of air or oxygen, this reaction initiates the autoxidation of the alkene. However, at concentrations below 100 parts per million in nitrogen, nitrogen dioxide reacts with cyclohexene almost exclusively by abstraction of allylic hydrogen; this unexpected reaction also initiates the autoxidation of the alkene in the presence of oxygen or air, but it leads to the production of nitrous acid rather than of a product containing a nitro group attached to a carbon atom.

Hemorrhagic shock treatment with hot intravenous fluid in dogs.

In hot climates, only high temperature fluids (are greater than 100 F) may be available for treatment of blood loss shock in combat casualties. Can the hot fluid be used safely and effectively? We compared hot Ringer's lactate (51.7% C/125 F) resuscitation (n=10) to body-temperature (100 F) fluid resuscitation (n=10) in a hemorrhagic shock dog model.

Advantages of potassium cardioplegia and perfusion hypothermia in left ventricular hypertrophy.

An attempt was made to determine the effect of hypothermic potassium cardioplegia (35 mEq of potassium chloride) on the hypertrophic ventricle. Puppies with induced left ventricular hypertrophy were divided into four groups and studied after one hour on global ischemia. Myocardial adenosine triphosphate (ATP) was best preserved in the hypothermically perfused groups and correlated well with measurements of coronary sinus creatine phosphokinase (CPK).

Plasma zinc levels in sheep in the peri-parturient period.

No consistent pattern of plasma zinc concentrations was observed in the peri-parturient period in 17 ewes, although large transitory depressions of plasma zinc levels were recorded in five ewes including one non-pregnant control. Sheep with dystocia did not exhibit a fall in plasma zinc similar to that recorded in cattle.