A thyromimetic that decreases plasma cholesterol levels without increasing cardiac activity

A number of agents that mimic the ability of the thyroid hormone, T3, to decrease plasma cholesterol levels are described; one is as effective as T3 at reducing cholesterol levels and stimulating liver function, but has very little effect on cardiac function and is thus less likely to be toxic. The agent may be useful in the treatment of atherosclerosis.     

Validating cancer drug targets

A cancer drug target is only truly validated by demonstrating that a given therapeutic agent is clinically effective and acts through the target against which it was designed. Nevertheless, it is desirable to declare an early-stage drug target as 'validated' before investing in a full-scale drug discovery programme dedicated to it. Although the outcome of validation studies can guide cancer research programmes, strictly defined universal validation criteria have not been established.     

Reproduction in urodeles II. Observations on the spermatheca

Zusammenfassung Die Spermatheca des Weibchens zeigt bei den untersuchten Urodelen eine innige Beziehung zu den Spermien, so dass eine Ernährungsfunktion der Spermatheca wahrscheinlich gemacht werden kann. Es wird auf die Sertoli-Zellen der Mammalia verwiesen.

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This work was supported by a grant from the Research Division of V.P.I.     

Soil-site relationships of white locoweed on the Raft River Mountains

White locoweed ( Oxytropis sericea Nutt.) is restricted to the top and windswept ridges of the Raft River Mountains. Elevation and soil characteristics have the greatest effect on its occurrence. It is most abundant on the subalpine windswept ridge ecological site (9.2 plants/m 2 ) above 2,380 m. White locoweed apparently can tolerate the extreme environmental stresses of the shallow, rocky, windswept ridges where it is one of the dominant species. White locoweed also occurs in the deep, subalpine loam site (3.8 plants/m 2 ) above 2,865 m, but it is a minor component of this plant community. It is apparently less competitive on the deeper soils, and its population fluctuates more. It exhibits an opportunistic survival strategy on the subalpine loam site by having a large reserve of viable seeds in the soil ready to germinate and establish when environmental conditions are favorable, and then declines with competition from more robust species.     

Ultrastructural differences in mitochondria of skeletal muscle in the prerigor and rigor states.

Loss of cristae and matrix occur in the mitochondria of skeletal muscles prior to any observable changes in myofibrillar proteins during the development of rigor mortis. Care must be observed because ultrastructural changes in mitochondria in some studies may be attributed to a specific trauma, whereas the changes may be due to the lower pH in postmortem muscle.     

The path toward prognostication and prediction in stage Ⅱ colon cancer

Currently, there are several newer biomarkers that may be clinically useful in colon cancer. This paper focuses on a few of these biomarkers, namely microsatellite instability, loss of heterozygosity at chromosome 18q （LOH18q） and multi-gene assays, and discusses the clinical evidence behind their predictive or prognostic abilities. The results show that although there have been several newer prognostic factors identified, such as LOH18q and multi-gene assays, none of these factors can predict benefit from treatment. Therefore, ongoing prospective clinical trials are still needed to further assess the role and optimal use of these tests.     

Formation and resolution of recombination intermediates by E. coli RecA and RuvC proteins.

The recombination of DNA molecules has been reconstituted in vitro using two purified enzymes from Escherichia coli. RecA protein catalyses homologous pairing and strand exchange reactions to form intermediate DNA structures that are acted upon by RuvC. The newly identified RuvC protein resolves the intermediates by specific endonucleolytic cleavage to produce recombinant DNA molecules.