AN ASSESSMENT OF CHANGES WITH TIME IN THE MARKING PATTERNS USED FOR PHOTOIDENTIFICATION OF INDIVIDUAL SPERM WHALES, PHYSETER MACROCEPHALUS

We observed changes with time in the patterns of characteristic fluke markings used to identify sperm whales. Changes were categorized as minor, moderate, or major based on their severity. These change types were found to occur at rates of 0.9%, 11.8%, and 1.3% per individual per year, respectively. Gain and loss rates for each of seven different mark types were also calculated. The highest estimated rate was the gain of small nicks at 0.08 per individual per year. Most individuals identified by us possess at least a few characteristic marks and, therefore, changes of the type observed in this study are unlikely to severely affect their recognizability. For all but one mark type, gain rates were higher than loss rates, indicating that individuals may be accumulating marks with age. Over long periods this could eventually make individuals unrecognizable, with the result that population sizes calculated from these data may be overestimated. As long as photoidentification studies are conducted sufficiently often, and these changes are as gradual as they appear to be, this problem should be minimal.     

Nucleotide sequence of the VP1 gene of the foot-and-mouth disease virus strain A Venceslau

The VP1 coat protein of FMDV strain A Venceslau (Aven) consists of 213 amino acid residues. Serum neutralization tests demonstrated that strain Aven is closely related to strain A Argentina/79 (A₇₉) but significantly different from strain A₂₄ Cruzeiro (A₂₄). There is a strong correlation between the amino acid sequences and the serological data. Nucleotide and amino acid sequence analyses of VP1 showed that serologically related viruses (Aven and A₇₉) differ less in this region of the genome than those of serologically distinct viruses (Aven vs. A₂₄). The most significant variation between Aven and A₂₄ occurs at amino acid positions 43 to 46, in which all four residues are different.     

1-aminocyclopropane-l-carboxylic acid (ACC)—The transmitted stimulus in pollinated flowers?

Ethylene production and senescence of petals of pollinated carnation flowers were not prevented by removal of the ethylene produced by the gynoecium, suggesting that these events are a response to movement from the gynoecium of some stimulus other than ethylene gas. Application of 1-aminocyclopropane-1-carboxylic acid (ACC) to the stigmas caused an initial increase in gynoecium and petal ethylene production similar to that reported for pollinated flowers. This response was not seen in flowers whose stigmas were treated with indoleacetic acid (IAA). When [2-¹⁴C]ACC was applied to the stigmas of carnation flowers, radioactive ethylene was produced both by the gynoecia and by the petals. The possibility that ACC, transported from the stigmas to the petals, is responsible for the postpollination changes in carnation flowers is discussed.     

Opportunities for natural selection on DNA and protein at the Adh locus in Drosophila melanogaster

A study was made of environmental and genetic factors affecting the quantity and disposition of the alcohol dehydrogenase (ADH) protein in Drosophila melanogaster. It was found that the amount of enzyme per fly is greatly influenced by the environmental conditions in which it develops. A critical factor is the concentration of yeast in the medium. A high concentration of yeast can double the quantity of ADH. The yeast appears to act through the provision of protein, and the protein to act through the provision of threonine, which is already known to induce ADH in fungi. Various genetic factors affect the quantity of enzyme. Males have more ADH than females. Files homozygous for the Fast allele have more ADH than those homozygous for the slow allele, and the difference is greater in females than in males. One particular line (ve), homozygous for Slow, has approximately half the normal quantity of enzyme, and the quantity segregates with the electrophoretic allele. Lines differ in the relative amounts of ADH in the gut (including Malpighian tubules) and the fat body. In general it seems that slow lines have relatively more enzyme in the fat body. In a cross between ve and a line homozygous to Fast, the difference in tissue distribution segregated with the electrophoretic allele. It is argued, but not demonstrated, that the differences in quantity and tissue distribution are due to nucleotide substitutions in noncoding regions close to, or within, the structural gene. It seems likely that the observed environmental and genetic differences in the quantity and disposition of ADH will influence the relative selective values of the electrophoretic genotypes.     

Interaction of glutathione transferase from horse erythrocytes with 7-chloro-4-nitrobenzo-2-oxa-1,3-diazole

7-Chloro-4-nitrobenzo-2-oxa-1,3-diazole reacts with two thiol groups of the dimeric horse erythrocyte glutathione transferase at pH 5.0, with strong inactivation reversible on dithiothreitol treatment. The inactivation kinetic follows a biphasic pattern, similar to that caused by other thiol reagents as recently reported. Both S-methylglutathione and 1-chloro-2,4-dinitrobenzene protect the enzyme from inactivation. Analysis of the reactive SH group-containing peptide gives the sequence Ala-Ser-Cys-Leu-Tyr, identical with that of the peptide that contains the reactive cysteine 47 of the human placental transferase. In the presence of glutathione, the enzyme is not inactivated by this reagent, but it catalyzes its conjugation to glutathione. At higher pH values, 7-chloro-4-nitrobenzo-2-oxa-1,3-diazole reacts with 2 tyrosines/dimer and lysines, as well as with cysteines. Reaction with lysine seems essentially without effect on activity; whether the reactive tyrosines are important for activity could not be determined using this reagent only. However, 2 tyrosines among the 4 that are nitrated by tetranitro-methane are important for activity.     

The effect of polyamines on ethylene synthesis during normal and pollination-induced senescence of Petunia hybrida L. flowers

Senescence of Petunia hybrida L. flowers is accompanied by a climacteric pattern in ethylene production and a rapid decline in the levels of putrescine and spermidine during the preclimacteric phase. The decrease in spermidine is caused by the decline in the availability of putrescine which is initially synthesized from L-arginine via agmatine and N-carbamoylputrescine. Inhibition of putrescine and polyamine synthesis resulted in a rapid drop in the levels of putrescine and spermidine without resulting in a concomitant increase in ethylene production. These results indicate that polyamine synthesis is not involved in the control of ethylene synthesis through its effect on the availability of S-adenosylmethionine, and is confirmed by the results obtained with pollinated flowers. Treatment with polyamines may stimulate or suppress ethylene production in the corolla, depending on the concentrations applied. In unpollinated flowers the onset of the climacteric rise in ethylene production was accelerated after treatment with polyamines. However, in pollinated flowers this process was delayed as a result of treatment with low concentrations of polyamines. The effects of exogenous polyamines on ethylene production in both pollinated and unpollinated flowers indicate that ethylene synthesis in these flowers is not regulated by a feedback control mechanism. Although polyamines do not play a key role in the control of ethylene production during the early stages of senescence through their effect on the availability of S-adenosylmethionine, it appears that they play an important role in some of the other processes involved in senescence.Abbreviations ACC 1-aminocyclopropane-1-carboxylic acid - MGBG methylglyoxal bis-(guanylhydrazone) - SAM S-adenosylmethionine     

Introduction of Tn916 and pAM beta 1 into Streptococcus bovis JB1 by conjugation.

The transposon Tn916 and self-mobilizing plasmid pAM beta 1 were conjugated from Enterococcus faecalis to the ruminal bacterium Streptococcus bovis JB1. Transconjugants were identified by resistance to tetracycline (Tn916) or erythromycin (pAM beta 1) and by Southern hybridization analyses. Transfer frequencies were 7.0 x 10(-6) and 1.0 x 10(-6) per recipient cell for Tn916 and pAM beta 1, respectively. The transconjugants JB1/Tn916 and JB1/pAM beta 1 were used as donors for matings with E. faecalis, Bacillus subtilis, and the ruminal bacterium Butyrivibrio fibrisolvens. While pAM beta 1 was successfully transferred to all three organisms, Tn916 was transferred only into B. subtilis and B. fibrisolvens at very low frequencies. This is the first report of conjugal DNA transfers between two ruminal organisms.     

Myb expression is higher in malignant human colonic carcinoma and premalignant adenomatous polyps than in normal mucosa.

Expression of the protooncogene c-Myb protein was assessed in normal mucosa and in tumor samples resected from six patients. We found that the tumor samples always expressed higher levels of full length Myb protein than the normal tissue. This contrasts with the situation in c-myb-associated hemopoietic malignancies of the mouse and chicken, in which Myb proteins are generally amino or carboxyl truncated. Tissues from five patients with colonic adenomatous polyps were also examined and found to express levels of Myb that were, in general, intermediate between those found in normal tissues and tumors. Of particular interest is that the more dysplastic polyps displayed higher Myb levels. In one patient with carcinoma and multiple colonic polyps, some polyps had intermediate levels of Myb, whereas one polyp with carcinoma in situ expressed tumor-like levels of Myb. To directly test the hypothesis that Myb expression may be important in determining the rate of colonic cell proliferation, we examined three colonic carcinoma cell lines and one polyp cell line. We found that the cell lines with the most rapid doubling times exhibited the highest Myb levels. In addition, we show that antisense myb oligonucleotides retard the proliferation of one of these colonic cell lines which expresses the highest level of Myb.     

Dose responses for Colletotrichum lindemuthianum elicitor-mediated enzyme induction in French bean cell suspension cultures

The induction of L-phenylalanine ammonialyase (PAL, EC 4.3.1.5) and flavanone synthase in French bean cell suspension cultures in response to heat-released elicitor from cell walls of the phytopathogenic fungus Colletotrichum lindemuthianum is highly dependent upon elicitor concentration. The elicitor dose-response curve for PAL induction shows two maxima at around 17.5 and 50 g elicitor carbohydrate per ml culture, whereas the flavanone synthase response shows one maximum at around 100 g ml^-1. The PAL response is independent of the elicitor concentration present during the lag phase of enzyme induction; if the initial elicitor concentration is increased after 2 h by addition of extra elicitor, or decreased by dilution of the cultures, the dose response curves obtained reflect the concentration of elicitor present at the time of harvest. PAL induction is not prevented by addition of methyl sugar derivatives to the cultures; -methyl-D-glucoside, itself a weak elicitor of PAL activity, elicits a multiphasic PAL response when increasing concentrations are added in the presence of Colletotrichum elicitor. Eight fractions with different monosaccharide compositions, obtained from the crude elicitor by gel-filtration, each elicit different dose-responses for PAL induction; the response to unfractionated elicitor is not the sum of the response to the isolated fractions. There is no correlation between the ability of the fractions to induce PAL in the cultures and their ability to act as elicitors of isoflavonoid phytoalexin accumulation in bean hypocotyls.Abbreviations PAL phenylalanine ammonia-lyase - PMS Phytophthora megasperma var sojae     

Immune competence in breast cancer — Relationship of pretreatment immunologic tests to diagnosis and tumor stage

Summary The immune competence of a group of 276 patients with suspected breast cancer has been assessed using a spectrum of tests: the peripheral lymphocyte count, serum immunoglobulin levels, lymphocyte response to phytohemagglutinin (PHA), Mantoux test, and dinitrochlorobenzene (DNCB) skin test. All tests were completed prior to any form of treatment as the initial part of an ongoing, long-term assessment which will ultimately relate immune competence to prognosis. 225 patients with breast cancer were allocated into stages based on their TNM status. The remaining 51 patients proved to have benign breast disease and made up the control group. In analysis, control patients were compared with early breast cancer patients, while the effect of advancing disease was assessed by betweenstage comparisons in the cancer group.There were no significant differences between early breast cancer and control patients or between cancer stages in peripheral lymphocyte count, serum immunoglobulin levels, lymphocyte response to PHA, or Mantoux responses. Age was found to have a crucial effect on some of these parameters and some apparent differences between the various groups lost significance after appropriate allowances were made for age.Important differences seen with the DNCB test persisted after allowing for age effects. Responses to DNCB were significantly depressed in patients with early breast cancer compared to controls. Patients with disseminated cancer showed greater depression than early breast cancer patients, but surprisingly, patients with locally advanced tumors had good responses to DNCB. Possible reasons for the paradoxical preservation of DNCB reactivity in patients with locally advanced cancer are discussed.The DNCB test is the most discriminating of the five tests of immune function studied.