Habitat disturbance and the diversity and abundance of ants (Formicidae) in the Southeastern Fall-Line Sandhills.

We examined habitat disturbance, species richness, equitability, and abundance of ants in the Fall-Line Sandhills, at Fort Benning, Georgia. We collected ants with pitfall traps, sweep nets, and by searching tree trunks. Disturbed areas were used for military training; tracked and wheeled vehicles damaged vegetation and soils. Highly disturbed sites had fewer trees, diminished ground cover, warmer soils in the summer, and more compacted soils with a shallower A-horizon. We collected 48 species of ants, in 23 genera (141,468 individuals), over four years of sampling. Highly disturbed areas had fewer species, and greater numbers of ants than did moderately or lightly disturbed areas. The ant communities in disturbed areas were also less equitable, and were dominated by Dorymyrmex smithi.

Regulation of hypertrophic and apoptotic signaling pathways by reactive oxygen species in cardiac myocytes.

Increasing evidence suggests that oxidative and nitrosative stress play an important role in regulation of cardiac myocyte growth and survival. The cardiovascular system is continuously exposed to both reactive oxygen species (ROS) and nitrogen species (RNS), collectively termed reactive inflammatory species (RIS), and imbalances between the enzymes that regulate their bioavailability are associated with cardiac hypertrophy and the pathogenesis of cardiomyopathies, myocardial infarction and heart failure. It is now clear that RIS act as critical regulators of cardiac myocyte hypertrophy and apoptosis through control of redox-sensitive signaling cascades, such as tyrosine kinases and phosphatases, protein kinase C, and mitogen-activated protein kinases. This review will focus on the mechanisms by which ROS/RNS modulate cardiac myocyte growth and apoptosis induced by neurohormones and cytokines, and will discuss evidence for a role in the pathophysiology of heart failure.

[Intrathoracic half-working heart and lung transplantation in the rat].

A new technique of intrathoracic half-working heart-lung transplantation in the rat was established. Donor heart-left lung graft was transplanted into left hemithorax of the recipient with aorta-aorta, bronchus-bronchus and superior vena cava (SVC)-SVC anastomoses, and the recipient's descending aorta proximal to the anastomosis was ligated. Five isografts (Lewis-Lewis) showed excellent cardiopulmonary function 4 weeks after transplantation. In 11 allografts (DA-Lewis), 5 rats without immunosuppression survived in 4-6 postoperative days and 6 rats with cyclosporine 10 mg/kg/day were alive during 8-14 days after operation. Nine of 11 allografts demonstrated moderate to severe (ISHLT grade 3-4) acute rejection and the grade of lung rejection was higher than that of heart rejection in 4 of 9 allografts.

Nitroglycerin compatibility with intravenous fluid filters, containers, and administration sets.

The effect of intravenous filters, containers and administration sets on nitroglycerin potency was studied. Solutions of nitroglycerin (50 and 100 microgram/ml) in water for injection, in 5% dextrose injection and in 0.9% sodium chloride injection were prepared. The concentration of these solutions was measured after (1) filtration through a 0.2-micron filter, (2) storage in glass and plastic containers and (3) administration through eight i.v. administration sets. Filters decreased nitroglycerin concentration by 2--55%. Nitroglycerin concentration was not changed after storage for 48 hours in glass bottles. In plastic i.v. bags, concentration decreases were substantial and related to surface contact area and storage temperature. The i.v. administration sets caused immediate, substantial decreases in nitroglycerin concentration that were a function of drip rate, surface area, length of exposure to tubing, and tubing materials. The study suggests that concentrations of nitroglycerin solutions could be reduced by as much as 80% when filtered, placed in a plastic i.v. bag and given through an i.v. administration set.

Comparison of in vitro dissolution and in vivo bioavailability of methaqualone tablets in humans.

Two methaqualone tablets that exhibited different in vitro dissolution rates were administered to 11 normal healthy male volunteers. Serial blood samples were withdrawn following administration of each tablet, and plasma methaqualone concentrations were determined by an established spectrophotofluormetric assay. Both tablets produced virtually identical plasma concentration versus time profiles in humans, and no statistically significant differences in either the rate or extent of drug absorbed were detected. The results indicate that there is no correlation between in vivo bioavailability and the modified NF in vitro dissolution test used.

Evaluation and characteristics of currently available inulin.

Inulin was not available for clinical testing in the United States between February 1973 and July 1975 because the raw material received in the United States differed from previously manufactured lots in molecular weight, glucose content, optical rotation, melting point, and water solubility. The comparability of the "new" and "old" inulin preparations was assessed in 12 adult male spinal cord injury patients, seven with normal renal function and five with compromised function. The "new" inulin proved to be as accurate and safe an agent for the determination of glomerular filtration rate as the previously available material in both groups of patients, and was made available for general clinical use in the United States in July 1975.

Solid state studies of the radiation history of lunar samples.

Particle track densities up to > 3 x 10(9) per square centimeter have been measured in different samples. Rocks 17, 47, 57, and 58 have VH (Z >22) galactic cosmic ray ages of 11, 14, 28, and 13 x 10(6) years, respectively. Rock 57 has a calculated erosion rate of 10(-7) centimeter per year. Near-surface track versus depth data in rock 17 can be fit with solar flare particles that have a differential energy spectrum aE(-3); lunar samples can be used to study the history of solar activity. The uranium in the crystalline rocks occurs principally in small regions <10 to approximately 100 micrometers in size. The (low) thermoluminescence of the fines increases with depth in core 10004. With one possible exception, x-ray studies have not shown pronounced radiation damage effects. The total energy release upon heating is small up to 900 degrees C and occurs in three broad regions.