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Congenital syphilis presented itself as protracted diarrhoea with bloody stools at times and anemia in a six weeks old infant. In the later course of the disease, hepatosplenomegaly and signs of glomerular lesion developed, osteitis was diagnosed radiologically.

Complex III (the cytochrome b-c1 complex) from beef heart mitochondria was incubated with [14C]DCCD for various periods of time. The polypeptide profile of the complex was compared in both stained gels and their autoradiograms when three different methods were used to terminate the reaction. Precipitation with ammonium sulfate resulted in the formation of a new band with an apparent molecular weight of 39,000 in both incubated samples and the zero time controls. Reisolation of the complex by centrifugation through 10% sucrose or by precipitation with trichloroacetic acid did not result in any changes in the appearance of the subunit peptides of the complex. Subunit III (cytochrome b) and subunit VIII were the only bands labeled after termination of the reaction by centrifugation through sucrose, while both ammonium sulfate and trichloroacetic precipitation resulted in nonspecific labeling of several other subunits of the complex and increased labeling of subunit VIII relative to subunit III. Preincubation of the complex with antimycin prior to treatment with [14C]DCCD resulted in a 50% decrease in the binding of DCCD to both cytochrome b and subunit VIII. Furthermore, treatment of the complex III with DCCD resulted in a change in the red shift observed after antimycin or myxothiazol addition to the dithionite-reduced complex resulting in a broad peak with no sharp maximum. These results provide further confirmation that DCCD binds preferentially to cytochrome b and subunit VIII of complex III from beef heart mitochondria and suggest that cytochrome b may play a role in proton translocation.

Changes of the complement components in the sera of 13 children with treated coeliac disease were studied after gluten challenge. The levels of C 1 and C3-activator (factor B) were significantly decreased at 4 h after the challenge, as were the levels of total complement (CH 50) and the components C 1, C 4 and C 1-inactivator at 8 h. After 24 h most values returned to normal but there was another significant decrease in serum C 4 after 24 h, and for CH 50, C 1, C 2 and C 4 after 48 h.

Since it has been demonstrated that endurance-trained cyclists are able to synthesize glycogen during mild exercise, glycogen synthesis was investigated in non-endurance-trained males and females as well. Seven males and nine females exercised on a cycle ergometer to deplete muscle glycogen. After the exhaustive exercise and taking a muscle biopsy, the males either exercised 2.5 h at 40% of maximal work load (trial A) or rested for 2.5 h (trial B). In both trials the subjects drank a 25% maltodextrin-fructose solution. After 2.5 h of exercise or rest, a second muscle biopsy was taken for determination of glycogen and for histochemistry (ATPase and PAS). In the females glycogen synthesis was only studied during 2.5 h rest, after prior glycogen depletion. In the male subjects, during mild exercise with carbohydrate feeding muscle glycogen did not increase. During rest muscle glycogen increased in the males from 123 +/- 49 mmol/kg DW at exhaustion to 229 +/- 70 mmol/kg DW (P less than 0.001), resulting in a net increase of 42 mmol/kg DW/h. Glycogen synthesis during rest occurred both in type I and type II fibers. In the females, during 2.5 h of rest, muscle glycogen increased from 130 +/- 56 mmol/kg DW at exhaustion to 224 +/- 51 mmol/kg DW, resulting in a net increase of 37 mmol/kg DW/h. The results demonstrate that glycogen synthesis during mild exercise does not occur in non-endurance-trained athletes, whereas in the resting state glycogen synthesis in non-endurance-trained males is not different from endurance-trained cyclists. In addition, glycogen synthesis during rest is similar in males and females.

To establish the interrelationship between protein synthesis and degradation, we have developed a simple procedure. We have chosen the mitochondrial proteins, because most of them are synthesized outside mitochondria and are then imported into the organelle. This fact allows to separate easily the synthesis steps from the general turnover. By using this system we have some evidences suggesting that the in vitro protein concentration in mitochondria may be regulated by the entry of mitochondrial protein precursors. Also, we are studying the factors that regulate the import of mitochondrial protein precursors into the organelle, because this step may be essential in the regulation of the turnover of mitochondrial proteins.

We have examined the effect of low molecular weight components of the transport mixture generally used for the import of rat liver pre-ornithine carbamoyltransferase by isolated rat liver mitochondria. These studies revealed that spermidine and spermine, at physiological concentrations, stimulate the transport of the precursor of ornithine carbamoyltransferase into mitochondria. This stimulatory effect of spermidine and spermine is concentration-dependent and is completely inhibited at higher than physiological concentrations (20 mM for spermidine and 4 mM for spermine). Magnesium ions, which also have a stimulatory effect, inhibit the stimulatory effect of spermidine.

Tuberization in potato is a complex developmental process involving the expression of a specific set of genes leading to the synthesis of tuber proteins. We here report the cloning and analysis of mRNAs encoding tuber proteins. From a potato tuber cDNA library four different recombinants were isolated which hybridized predominantly with tuber mRNAs. Northern blot hybridization experiments showed that three of them, pPATB2, p303 and p340, can be regarded as tuber-specific while the fourth, p322, hybridizes to tuber and stem mRNA. Hybrid-selected in vitro translation and nucleotide sequence analysis indicate that pPATB2 and p303 represent patatin and the proteinase inhibitor II mRNA respectively. Recombinant p322 represents an mRNA encoding a polypeptide having homology with the soybean Bowman-Birk proteinase inhibitor while p340 represents an mRNA encoding a polypeptide showing homology with the winged bean Kunitz trypsin inhibitor. In total, these four polypeptides constitute approximately 50% of the soluble tuber protein. Using Southern blot analysis of potato DNA we estimate that these mRNAs are encoded by small multigene families.

The stability of hepatic delta-aminolevulinic acid synthase (ALAS), the first and rate-limiting enzyme of the heme biosynthetic pathway, was investigated. Incubation of the mitochondrial matrix fraction obtained from either control or allylisopropylacetamide-induced rats at 37 degrees C in Tris-Cl, pH 7.4, EDTA, and dithiothreitol resulted in a rapid decrease in ALAS activity such that 50-70% of the activity was lost after 30 min. Similar decreases in ALAS activity were observed when a cytosolic fraction from the induced animals was incubated at 37 degrees C. Addition of 0.1 mM pyridoxal-P, the cofactor of ALAS, to the preincubation medium completely prevented the observed loss of activity; however, dialysis of the inactive matrix fraction against several changes of buffer containing pyridoxal-P did not restore activity, suggesting that the inactivation was irreversible. These decreases in ALAS activity in the absence of pyridoxal-P were temperature dependent, as a 55% loss of ALAS activity was observed after a 60-min incubation at 30 degrees C, while the enzyme was completely stable when preincubated at 22 degrees C for 60 min. This inactivation of ALAS does not appear to involve proteolytic digestion, as addition of a wide spectrum of protease inhibitors to the preincubation medium in the absence of pyridoxal-P did not protect against the inactivation. The suggestion is made that the cofactor, pyridoxal-P, may dissociate from the enzyme during the preincubation and, consequently, the apoenzyme may be irreversibly inactivated at temperatures above 22 degrees C.

The chief conclusion to be drawn from the results of this study is that redwoods are amazingly vigorous. The results support both the lumber companies and the conservationists. There is no question that old growth giant redwoods must be preserved. Only commercial greed could be a basis for refuting that stand. On the other hand, the lumber companies seem to be supported in their contention that redwoods can be farmed without driving them to extinction. The central issue revolves around the old trees. And here profit is the big factor. Lumbering is an important industry in California, and redwood lumbering represents about 20 percent of the industry (l). Most of the big names in timber, such as Weyerhaeuser and Georgia-Pacific, are involved in logging the California redwood. At the current rate of logging, particularly of old growth stands, the Bank of America estimates that employment in Humboldt County will be down significantly by 1975 (4). It has been argued that tourism would more than compensate for the lower employment in logging. But not if the trees that the tourists come to see are gone. Why can't young and mature trees be harvested at a reasonable rate, the old trees saved, and both tourism and logging flourish? The question posed earlier has been answered. Redwood growth and survival can be modeled, using matrix methods in a new context. Meaningful conclusions may be drawn. And the results are sufficiently tantalizing to inspire further research.