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51.
Angela B. Lange Ian Orchard Vicki A. Te Brugge 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1991,168(3):383-391
Summary The presence of a SchistoFLRFamide-like peptide associated with the oviducts of Locusta migratoria has been shown using sequential reversed-phase high performance liquid chromatography separation coupled with radioimmunoassay and bioassay. The peptide is present in areas of the oviduct which receive extensive innervation, with sixfold less peptide in areas that receive little innervation. Material with FMRFamide-like immunoreactivity (determined by radioimmunoassay) is also present in the oviducal nerve and VIIth abdominal ganglion.SchistoFLRFamide is a potent modulator of contraction of this visceral muscle, inhibiting or reducing the amplitude and frequency of spontaneous contractions, relaxing basal tonus, and reducing the amplitude of neurally-evoked, proctolin-induced, glutamate-induced and high potassium-induced contractions. The FMRFamide-like immunoreactivity within the oviducts which co-elutes with SchistoFLRFamide on two separations is also capable of reducing the amplitude of neurally-evoked and proctolin-induced contractions, and of inhibiting spontaneous contractions and relaxing basal tonus.The effects of SchistoFLRFamide upon this visceral muscle are not abolished by the -adrenergic receptor antagonist phentolamine and do not appear to be mediated by cyclic AMP. Thus the receptors for Schisto-FLRFamide are distinct from those of octopamine which mediate similar physiological effects but which are blocked by phentolamine and which are coupled to adenylate cyclase.The results indicate that SchistoFLRFamide, or a very similar peptide, which has previously been identified as a modulator of locust heart beat, is also associated with visceral muscle of the reproductive system, and may play a neural role in concert with octopamine, at modulating muscular activity.Abbreviations
BPP
Bovine pancreatic polypeptide
-
BSA
Bovine serum albumin
-
EJP
Excitatory junctional potential
-
FaRPs
FMRFamide-related peptides
-
FLI
FMRFamide-like immuno-reactivity
-
LMS
Leucomyosuppressin
-
RIA
Radioimmunoassay
-
RP-HPLC
Reversed-phase high performance liquid chromatography
-
TFA
Trifluoroacetic acid 相似文献
52.
The malmö polymorphism of coagulation factor IX, an immunologic polymorphism due to dimorphism of residue 148 that is in linkage disequilibrium with two other F.IX polymorphisms
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John B. Graham Dennis B. Lubahn Susan T. Lord Julie Kirshtein Inga Marie Nilsson Anders Wallmark Rolf Ljung L. D. Frazier Jerry L. Ware Shu Wah Lin Darrell W. Stafford John Bosco 《American journal of human genetics》1988,42(4):573-580
A mouse monoclonal antibody (MAB 9.9) to coagulation factor IX (F.IX) detects a polymorphism in the plasma of normal people. Its epitope has been narrowed down to <6 amino acids in the activation peptide of the X-linked F.IX protein. The activation peptide contains a dimorphism—Thr:Ala—at position 148 of the protein. Using synthetic oligonucleotides, we have demonstrated that (1) the F.IX which reacts with 9.9 has Thr at position 148 and (2) that which does not has Ala. Positive reactors (148thr) are designated Malmö A, and negative reactors (148ala) are designated Malmö B. The plasma levels of AA women are indistinguishable from those of A men, and both B men and BB women are null against MAB 9.9. The plasma level of Malmö A in AB women is approximately half that of AA women, and “lyonization” is clearly operating in the heterozygotes. The dimorphism is in strong linkage disequilibrium with two other intragenic RFLPs, TaqI and XmnI. Furthermore, intragenic crossing-over—including double crossing-over—appears to have occurred between the three sites. Seven of the eight possible haplotypes have been identified, five in men and two others in women. The immunoassay that identifies ~50% of the AB women in the pool of Malmö A females with 95% confidence identifies men unambiguously as A or B. The assay would be very useful for population-genetic studies of the Malmö epitope if the studies were limited to men. 相似文献
53.
A deoxyribonuclease was partially purified from the free-living nematodeCaenorhabditis elegans. The DNase functioned as an endonuclease and introduced both single-strand nicks and double-strand breaks into DNA. The enzyme
hydrolyzed double-stranded DNA seven times more rapidly than single-stranded DNA. DNase activity was not affected by the addition
of divalent cations below 1mm but was inhibited at higher ionic concentrations. In addition, the enzyme was not inhibited in the presence of 10mm EDTA. The enzyme was inhibited by salt concentrations greater than 20mm. Three independent mutations in thenuc-1 gene were shown to reduce nuclease activity to less than 1% of that seen in wild-type organisms.
This work was supported by National Institutes of Health Grant AG03161 and a TCU Research Foundation Grant. Some stocks used
in these experiments were obtained from theCaenorhabditis Genetics Center, which is supported by Contract NOI-AG-9-2113 between the NIH and the curators of the University of Missouri. 相似文献
54.
Cell suspension cultures of the Madagascan Periwinkle Catharanthus roseus (L) G. Don were maintained on Gamborg's B5 medium and their growth monitored by measuring cellular fresh and dry weight, cell number and mitotic activity. Samples of cells of different ages and physiological states were subcultured onto an alkaloid production medium and their rates of growth and alkaloid accumulation measured over a period of 30–45 days. In two experiments the rate of biomass accumulation was directly related to the rate of cellular serpentine accumulation. Possible mechanisms underlying this phenomenon are discussed in relation to the properties of cells comprising the inocula. 相似文献
55.
Whole homogenates of bulb mites rapidly metabolized 2-phenylethylamine (PEA) but were appreciably less active against tryptamine, 5-hydroxytryptamine, and dopamine; no degradation of octopamine was detected. The rate of PEA degradation by bulb mites was dependent upon both substrate and homogenate concentrations. PEA degradation was inhibited by pargyline (pI50, 6.7), tranylcypromine (pI50 6.2), and harmaline (pI50 4.1), but not by 5-chloro-2,4-dimethoxyformanilide. These results suggested that PEA metabolism by bulb mite homogenates was catalyzed mainly by Type B monoamine oxidase.Contribution from the Missouri Agricultural Experiment Station, Columbia, MO. Journal Series No. 9777 相似文献
56.
Julie Marcus 《The Australian journal of anthropology》1987,17(3):185-197
Olive Pink studied anthropology at the University of Sydney under Professor A.P. Elkin. Although she did fieldwork among the Northern Aranda and Wailbri of Central Australia, she became disenchanted with anthropology and lived a reclusive life in Alice Springs. In this paper I present a brief outline of her life, particularly during the 1930's I point to the problems she encountered and suggested that she needs to be relocated within her discipline. 相似文献
57.
G. Gray Eaton Deanne F. Johnson Barbara B. Glick Julie M. Worlein 《Primates; journal of primatology》1986,27(2):141-150
We have quantitatively documented the development of sex differences in the behavior of juvenile Japanese macaques (1 to 2
years of age). Mothers treated their offspring differently by sex, i.e., mothers of males broke contact with them more frequently
than did mothers of females. Juvenile males played more, and mounted other macaques more frequently; juvenile females groomed
their mothers more and were also punished by other group members more frequently than were males. Males showed a pattern of
decreasing interactions with their mothers, but females increased the frequency of their maternal interactions. These patterns
appear to presage the life histories of the sexes. However, comparisons with other species of nonhuman primates indicate that
although sex differences in behavior are common, the variability among species severely limits cross-specific generalizations. 相似文献
58.
Sandra N. Hing Carolyn M. Giles Angela H. L. Fielder J. Richard Batchelor 《Immunogenetics》1986,23(3):151-155
Twenty-three individuals from various disease groups and normal controls were identified by immunofixation with anti-C4, C4-dependent lysis, determination of Rg (Rodgers) and Ch (Chido) phenotypes, and immunoblotting with C4-specific mouse monoclonal antibody. We found that one haplotype predominates with the C4B
*
5 allele, HLA-A11, B22(55), Cw3, Bf
*
S, C4A
*
4B
*
5, which also carries the Ch
1,–2, 3 haplotype. The B5 allotype was also found with HLA-1360, HLA-1335 in Caucasoids, and HLA-B18 in non-Caucasoids; these carried the Ch
–1, –2, –3 haplotype. Our results are in accord with an earlier report of two B5 subtypes, B5Rg+ and B5Rg– (Roos et al. 1984). The specificity of the mouse monoclonal antibodies IC4 and 21312 had been previously related to C4A and C4B, respectively, but our results suggest that they relate more closely to Rg and Ch determinants. 相似文献
59.
Barbara Beckerman Glide G. Gray Eaton Deanne F. Johnson Julie Worlein 《International journal of primatology》1986,7(2):139-155
The behavioral interactions of 22 infant and mother Japanese macaques with other group members were studied. Focal-animal
observations were made from the time of each infant’s birth until 1 year of age. Infants and mothers both displayed exceedingly
strong preferences for associating with matrilineal kin and, specifically, for female kin. The degree of genetic relatedness
was positively correlated with levels of spatial proximity, contact, grooming, aggression, and play. Overall frequencies of
interactions with nonkin were very low, and partner sex was not an important factor in interactions with nonkin. There were
no significant differences between male and female infants in interactions with kin versus nonkin. There was only one significant
difference between male and female infants in interactions with males versus females: female infants showed stronger preferences
for initiating proximity with females over males than did male infants. Because mothers provide the focal point for infant
interactions during the first year of life, we compared the behavior of infants and mothers. Mothers were the recipients of
more social interactions than were infants, mothers engaged in more grooming than did infants, and infants engaged in more
social play than did mothers. These findings are only partially consistent with kin-selection theory, and the inadequacies
of studying matrilineal kin discrimination to test kin selection are reviewed. The near-absence of infant sex differences
in associations with social partners suggests that although maternal kin other than the mother are important to infant socialization,
they probably do not contribute to the development of behavioral sex differences until after the first year of life. 相似文献
60.
Glick Barbara Beckerman Eaton G. Gray Johnson Deanne F. Worlein Julie M. 《International journal of primatology》1986,7(5):467-479
Quantitative data are presented on the effects of subject sex, partner sex,and kinship on the social interactions of 18 juveniles of the Oregon troop of Japanese macaques (Macaca fuscata).Data on these subjects as infants were also used to detail maturational changes in partner sex preferences. Nine males and
nine females, whose multiparous mothers represented a cross section of dominance ranks, were observed using a focal-animal
technique. Juveniles of both sexes engaged in more proximity, contact, grooming, mounting, aggression, and social play with
kin than with nonkin partners. They initiated less contact with females and more contact with males during their second year.
They initiated more grooming and aggression during their second year than their first year, with females displaying a strong
preference for grooming females and males specifically aggressing males more during the second year. Aggression was higher
between same-sexed partners than between opposite-sexed partners. Males engaged in more social interactions with males during
the second year than the first year of life. Males played more than females during both years. Males played more with males
during the second year than the first year, and males played with males more than did females during the second year. We conclude
that sex differences in behavioral frequencies become evident during the first year of life, and sex differences in partner
preferences emerge during the second year of life. 相似文献