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Consistently high tuberculosis rates in many developing nations, the surprising increase in tuberculosis cases in numerous industrialized countries, together with the emergence of multi-drug-resistant strains of Mycobacterium tuberculosis have sharpened public interest in this ancient scourge. Improved tuberculosis control could best be achieved by an efficacious vaccine. The available attenuated vaccine strain, Mycobacterium bovis BCG, has only limited efficiency. This vaccine is capable of protecting against disseminated miliary tuberculosis in the newborn, but it is unable to prevent stable infection and to cause sterile pathogen eradication. Hence, adult tuberculosis, representing the majority of all tuberculosis cases, is not preventable by BCG vaccination. Due to the extraordinarily high rate of asymptomatic M. tuberculosis infection (1/3 of the total world population) any novel vaccination strategy has to fulfil two major tasks: first, prevention of stable infection, second, eradication of already established infection. T lymphocytes represent the major target for any vaccine strategy, because they serve as central mediators of acquired immunity. They segregate into distinct populations, characterized by different activation conditions and biological functions. These T cell populations do not act independently from, but rather interact with, each other mostly through cytokines. Although CD4 T lymphocytes of T helper 1 type are essential for protection, CD8 T cells expressing cytolytic functions are required, in addition. Perhaps other T cell populations, such as gamma/delta T cells and double negative alpha/beta T cells, also participate. An effective vaccine has to stimulate the precise combination of T cells and cytokines required for the different tasks. It remains to be clarified in how far this can be achieved by a single vaccine.

To determine whether the addition of computed tomographic (CT) angiography to CT arterial portography would improve lesion detection and heighten confidence in interpreting perfusion abnormalities.The two examinations were performed sequentially in 10 candidates for surgical resection of hepatic tumors. Arterial vascular access was obtained with bilateral punctures of the common femoral artery and selective placement of angiographic catheters in the hepatic artery and superior mesenteric artery (SMA). CT scans were obtained first during injection of contrast material into the SMA, followed by repeated imaging of the liver during injection of contrast material into the hepatic artery.The procedure demonstrated, among other results, three additional lesions in two patients, a possibly nontumorous abnormality as tumorous in one, and a suspected tumorous abnormality as nontumorous in one. Suspected nontumorous abnormalities in four patients were confirmed at CT angiography.These preliminary data support a trial of this technique in a larger population.

Acute experiments in chickens demonstrated that glucagon inhibited the volume of spontaneous gastric juice secretion (proventriculus-gizzard) with a corresponding decrease in pepsin output. Glucagon did slightly reduce the volume of histamine-stimulated gastric juice, but the pepsin secretion decreased by 50%. The pentagastrin stimulatory effect on gastric secretion was suppressed by glucagon. The effect of glucagon on the proventriculus in chickens is very similar to its effect on gastric secretion in mammals.

A rebreathing method (usood volume (VTPC) was evaluated in 13 dogs. In seven, pulmonary edema was induced by oleic acid injection. Six dogs served as controls. Values of VTPC calculated by three algorithms were compared to postmortem lung water. The first algorithm uses the C18O intercept to determine time 0 and all data to construct the alveolar disappearance curves. The second uses the beginning of inspiration as time 0. The last uses data only during the last third of expiration. The best correlation (r = 0.90) between VTPC and total lung water was obtained utilizing the first algorithm. In the control animals, mean VTPC was 188 ml, and in the edema dogs was 278 ml. Mean VTPC for all dogs was 96 +/- 14% of total lung water using the first algorithm. Another algorithm (J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 44: 782-795, 1978) was evaluated inthe edema dog group. This method gave values of VTPC 53% higher than those obtained by the first algorithm.