Multiple Copies of Human Adenovirus 12 Genomes Are Integrated in Virus-Induced Hamster Tumors

Tumors induced in hamsters by highly oncogenic human adenovirus 12 contain multiple copies of 90 to 100% of the viral genome in an integrated form.     

Myocardial Revascularization in Patients 70 Years of Age and Older

Myocardial revascularization has been carried out by us in 67 patients 70 years of age or older. Advanced coronary artery disease was found at angiography in more than two thirds of the patients. The postoperative morbidity and mortality compare very favorably with those in younger patients. The early and late mortality in the 67 patients was 4.5 percent and 6.0 percent, respectively. Fifty-seven survivors have been followed an average of 21 months; for most patients there has been a pronounced improvement in clinical classification. Properly selected, patients of advanced age can undergo successful revascularization surgical procedures. The adequacy of function of the left ventricle, proper timing of the surgical operation and an aggressive yet realistic approach seem to be major determinants for a good result.     

Specific binding of T lymphocytes to macrophages. III. Spontaneous dissociation of T cells from antigen-pulsed macrophages.

Peritoneal exudate lymphocytes (PEL) from immune guinea pigs that adhere to antigen-pulsed macrophages (MO) were cultured for 1 week to yield a population enriched in antigen-specific (selected) T cells. These cells bind specifically within hours to fresh autologous antigen-pulsed MO. Thd dissociation of these selected PEL from antigen-pulsed MO was studied. No evidence was obtained that factors in the culture medium play a role in dissociation. Lymphocytes that have dissociated from antigen-pulsed MO are usually fully capable of rebinding to MO freshly pulsed with antigen, suggesting that there is no deficiency in the lymphocytes ability to bind. In contrast, readding antigen to cultures during incubation prevents the predicted dissociation. Moreover, repulsing MO cultured without selected PEL restores their capacity to bind fresh selected PEL. These findings indicate that decay of antigen associated with with MO is the major mechanism underlying the observed dissociation.     

The origin of mentha — gracilis (Lamiaceae). II. essential oils

Essential oils were eamined in nine clones of Mentha arvensis, four clones of M. spicata, and 20 clones of M. gracilis. An F₁ hybrid of M. arvensis M. spicata, selected on the basis of morphology and chromosome number, was matched with one clone of M. Gracilis. Genes for the inheritance of limonene, 1,8-cineole, linalool, isomenthone, carvone, and piperitenone oide were identified in one clone of M. arvensis and two clones of M. spicata. The range of essential oil compounds detected indicates that no one character can be used to identify M. gracilis, but the critical compounds of the oil of M. gracilis can be derived from crosses of M. arvensis M. spicata.     

Effect of N,N-Dicyclohexylcarbodiimide on Acetylcholine Release from Torpedo Synaptosomes and Proteoliposomes Reconstituted with the Proteolipid Mediatophore

The mediatophore is a presynaptic membrane protein that has been shown to translocate acetylcholine (ACh) under calcium stimulation when reconstituted into artificial membranes. The mediatophore subunit, a 15-kDa proteolipid, presents a very high sequence homology with the N,N'-dicyclohexylcarbodiimide (DCCD)-binding proteolipid subunit of the vacuolar-type H(+)-ATPase. This prompted us to study the effect of DCCD, a potent blocker of proton translocation, on calcium-dependent ACh release. The present work shows that DCCD has no effect on ACh translocation either from Torpedo synaptosomes or from proteoliposomes reconstituted with purified mediatophore. However, using [14C]DCCD, we were able to demonstrate that the drug does bind to the 15-kDa proteolipid subunit of the mediatophore. These results suggest that although the 15-kDa proteolipid subunits of the mediatophore and the vacuolar H(+)-ATPase may be identical, different domains of these proteins are involved in proton translocation and calcium-dependent ACh release and that the two proteins have a different membrane organization.     

The origin ofMentha X gracilis (Lamiaceae). I. Chromosome numbers,Fertility, and three morphological characters

Employing nine clones ofMentha arvensis and four clones ofM. spicata, 932 F, hybrids were synthesized and compared to 20 clones ofM. x gracilis. Two clones ofM. x gracilis with 60 somatic chromosomes were matched to a selected F₁ hybrid. The other 18 clones ofM. x gracilis had somatic chromosome numbers of 60, 72, 84, and 96, and while these chromosome numbers appeared in the F₁ progeny, morphological matches correlated with their correct chromosome numbers were not synthesized. The range of pollen and seed fertility, as well as the inheritance of male-sterility, leaf pubescence, and crispness, indicates that no one character can be used to identifyM. x gracilis, but all characters can be explained fromM. arvensis x M. spicata.     

Progestin binding in mammary tissue of prepartum,nonlactating and postpartum,lactating cows

Binding of [³H]R5020 (17,21-dimethyl-19-nor-4,9-pregnadiene-3, 20-dione) to bovine mammary cytosol indicated the presence of progestin binding sites of high-affinity and low-capacity in tissue from prepartum, nonlactating and from postpartum, lactating cows. To prevent binding of [³H]R5020 to glucocorticoid binding sites, a 200-fold molar excess of nonradioactive cortisol was included during all incubations, thus specific binding was limited to progestin binding sites. Nonradioactive R5020 and progesterone effectively inhibited [³H]R5020 binding to progestin binding sites, while estradiol-17β, dihydrotestosterone (17β-hydroxy-5α-androstan-3-one), dexamethasone (9-fluoro-11β, 17, 21-trihydroxy-16α-methyl-1,4-pregnadiene-3,20-dione) or additional cortisol were ineffective. Dissociation constants for specifically bound [³H]R5020 in cytosol from mammary tissue of nonlactating and lactating cows were nearly identical, averaging 1.9 ( ± 0.3) and 0.8( ± 0.2) × 10?⁹M, respectively. However, binding capacities (fmol/mg cytosolic protein) were greater in cytosol from prepartum, nonlactating (179 ± 53) than postpartum, lactating (41 ± 15) cows. Specific binding components in cytosol from lactating cows sedimented in the 6-7S region on linear sucrose density gradients. When subjected to isoelectric focusing, specific binders with isoelectric points (pI) of approximately 6.1, 7.9 and 8.3 were resolved. The decrease in number of binding sites during lactation was due to the virtual absence of the anionic binding species, suggesting that their presence is necessary for progesterone to inhibit milk secretion.     

Mutations within an intron and its flanking sites: Patterns of novel polypeptides generated by mutants in one segment of the cob-box region of yeast mitochondrial DNA

Summary We have undertaken a systematic examination of the polypeptides accumulating in thirteen (out of 23) mutants in the intron cluster box7 and its flanking clusters box2 and box9 of the cob-box (cytochrome b) region of the mitochondrial genome of Saccharomyces cerevisiae. We have subjected these polypeptides to fingerprint analysis, both sequential and in parallel, with two proteases in order to disclose sequence homologies and differences between the different novel polypeptides themselves, and between them and the wild type product of the gene, i.e. apocytochrome b. One of our aims has been to establish the existence of possible correlations between the nature of the novel polypeptides and the fine structure genetic map of that segment of the mitochondrial genome.Our results show that all box7 mutants accumulate the following set of polypeptides not seen in wild type cells: a) a characteristic set of large polypeptides consisting of three species: p56, p42 and p35 or p34.5; b) a polypeptide p23; c) a much shorter fragment (of which the apparent molecular weight varies from 12.5 to 13, according to the mutation) with the exception of two mutants; d) in addition, the majority accumulate in varying amounts a polypeptide p30 closely related to but not identical with apocytochrome b.Moreover only two box7 mutants accumulate a polypeptide in the range of mobilities corresponding to 25–27 Kd (referred to as class p26) while such a polypeptide is seen in all box9 and box2 mutants examined with one exception in box2.Only one mutant in box2 resembles box7 mutants with respect to criterion a), and no box2 or box9 mutants resemble box7 mutants with respect to criterion c); criteria b) and d) appear to apply equally well to mutants in all three clusters.Fingerprint analysis, carried out with polypeptides p56, p42, p35, p34.5, p30, p26, p23, discloses that a) The polypeptides belonging to the same class of mobility exhibit very similar if not identical sequences in various cases. b) These polypeptide classes, except p56, p42 and p26, share considerable sequence homologies with wild type apocytochrome b, perhaps encompassing 50% or more of the wild type sequences. b) Polypeptides belonging to the classes p42 and p26 exhibit less extensive but nevertheless significant homologies with the wild type sequence. c) Sequences in polypeptides belonging to class p56 are virtually indistinguishable from ones in cytochrome oxidase subunit I.The inferences from these findings are 1) one gene can produce a multiplicity of polypeptide products that share a common sequence at the promoter-proximal (N-terminal) portion, but diverge beyond these regions of homology. 2) Both the multiplicity of products in single mutants, and the protein structure found, argue against the divergent segments to be due to frameshift terminations, and instead suggest that the novel products are consequences of mRNA processing defects (excision and/or ligation) at and near intron regions. 3) Mutations at edges and the center of an intron can generate similar polypeptide patterns, i.e. produce analoguous mRNA processing defects. 4) Mutations in exons, at their boundary with introns, can produce polypeptide patterns indistinguishable from those at the neighbouring intron; they diverge and eventually become typically exonlike in mutants localized at increasing distances from the boundary. 5) Taken together these findings argue that pre-mRNA processing extends beyond the boundaries of the intron proper and that certain exonsequences participate in excision and ligation. 6) Accumulated pre-mRNAs, resulting from defects in splicing can be translated. 7) Product p56 is formally analogous to p23, as a faulty but highly conserved partial product of the wild type protein, the former of Cox I (oxi3 gene), the latter of the cob-box gene proper. Therefore both genes may utilize identical RNA processing elements which are affected by box7 mutations. 8) A small amount of product similar to p56 may accumulate even in some wild types but not in others. This observations suggests that in certain nuclear backgrounds RNA processing may be more error-prone than in others.Publication No. XXXX from the Department of Chemistry, Indiana UniversitySupported by Research Grant GM 12228 from the National Institute of General Medical Sciences, National Institutes of Health; recipient of Research Career Award K06 05060 from the same Institute.Supported by Délégation Générale à la Recherche Scientifique et Technique grant n⁰ 78-70341