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1.
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
2.
The regularity of a basketlike surrounding of parenchymatous parts of the liver by portal branches proves the lobular organization of the liver. The wall formation of the portal basket (corbicula portalis) is demonstrated by several figures. 相似文献
3.
Inga Sidén-Kiamos Guido Favia Dora Artiaco Giuseppe Saceone Maria Furia Lino C. Bolito Christos Louis 《Genetica》1993,92(1):43-53
The sequence determination of several genomic clones isolated from the Mediterranean fruitfly Ceratitis capitata identified the existence of opa-like repeats, often more than one being clustered in small chromosomal segments. These repeats have previously been shown to consist of stretches of tandemly reiterated glutamine-encoding residues, and they are found in multiple genes of several organisms. Most of the repeats described here are flanked or interrupted by stop codons in all reading frames and, thus, could not possibly be part of protein-coding sequences. Furthermore, these repeats, of which there are several hundred in the genome of the Medfly, can be used effectively for the determination of sequence polymorphisms, providing a convenient approach to obtain additional landmarks for the construction of genomic maps of this economically important insect.This paper is dedicated to the memory of our colleague and friend Dr. Jim Flach who took part in the initial phase of this work and died during the course of the investigation. 相似文献
4.
Maren Preuss Pilar Díaz-Tapia Heroen Verbruggen Giuseppe C. Zuccarello 《Journal of phycology》2023,59(5):950-962
Parasitic red algae are an interesting system for investigating the genetic changes that occur in parasites. These parasites have evolved independently multiple times within the red algae. The functional loss of plastid genomes can be investigated in these multiple independent examples, and fine-scale patterns may be discerned. The only plastid genomes from red algal parasites known so far are highly reduced and missing almost all photosynthetic genes. Our study assembled and annotated plastid genomes from the parasites Janczewskia tasmanica and its two Laurencia host species (Laurencia elata and one unidentified Laurencia sp. A25) from Australia and Janczewskia verruciformis, its host species (Laurencia catarinensis), and the closest known free-living relative (Laurencia obtusa) from the Canary Islands (Spain). For the first time we show parasitic red algal plastid genomes that are similar in size and gene content to free-living host species without any gene loss or genome reduction. The only exception was two pseudogenes (moeB and ycf46) found in the plastid genome of both isolates of J. tasmanica, indicating potential for future loss of these genes. Further comparative analyses with the three highly reduced plastid genomes showed possible gene loss patterns, in which photosynthetic gene categories were lost followed by other gene categories. Phylogenetic analyses did not confirm monophyly of Janczewskia, and the genus was subsumed into Laurencia. Further investigations will determine if any convergent small-scale patterns of gene loss exist in parasitic red algae and how these are applicable to other parasitic systems. 相似文献
5.
The influence of the choice of type and/or concentration of cyclodextrin, other additives, the temperature surrounding the capillary, and buffer pH on the separation of some chiral basic drug substances in capillary zone electrophoresis has been evaluated. It was found that pH of the buffer and type and concentration of cyclodextrin had a major influence on the separation. © 1995 Wiley-Liss, Inc. 相似文献
6.
Polyol accumulation by two filamentous fungi grown at different concentrations of NaCl 总被引:1,自引:0,他引:1
The accumulation of polyols by Aspergillus niger (van Tiegh) strain S 1 and Penicillium chrysogenum (Thom) strain S 30 was followed during growth in media of different concentrations of NaCl. The major polyols found were glycerol, erythritol and mannitol. The total polyol pool increased in both organisms in response to raised salinity, and the proportion of glycerol and erythritol was markedly enhanced at high salinity. 相似文献
7.
We used the incorporation of 14C-uridine into RNA of incubating kidney fragments from normal control rats to evaluate RNA metabolism. Sera from unilaterally nephrectomized rats (uni) obtained 20 hrs post-operatively stimulate 14C-uridine incorporation into RNA significantly more than sera from sham-operated rats (sham). Differently, sera from uni and sham rats have little influence on specific activities of endogenous uridine nucleotide pool in renal fragments. Renal extracts were obtained by homogenizing kidneys in saline. Extracts from kidneys of uni and sham rats 20 hrs post operation depress incorporation markedly, and each depresses to a similar extent, but kidney extracts dilute the specific activities of uridine pools. Correcting for the latter dilution demonstrates that kidney extracts alone have little effect on 14C-uridine incorporation into RNA. We then followed the results when these sera and extracts were combined. Compared to fragments incubating in sham sera and sham extracts, substitution of uni extracts or both uni extracts and uni sera enhances 14C-uridine into renal RNA, whether or not results are corrected for changes in the specific activities of the uridine pools. We conclude that after uninephrectomy there is a concurrent elevation in circulating renotropin and a tissue activating factor in the remaining kidney. The tissue factor can only form an excitor to 14C-uridine incorporation into RNA when serum is present. The rat renotropic system that enhances incorporation of 3H-thymidine into DNA also can stimulate 14C-uridine incorporation into renal RNA. 相似文献
8.
P Campomenosi R Iannone A Inga P Menichini P Degan A Abbondandolo G Fronza 《Bollettino della Società italiana di biologia sperimentale》1992,68(11):699-705
To understand molecular mechanisms of the mutation fixation process induced by a mutagen and carcinogen, a multi-system approach is suggested to reduce the probability that the results are biased by the assay used. In this light we described our different approaches to answer basic questions on the mutagenesis induced by the chemical carcinogen 4-Nitroquinoline-1-oxide. We determined mutations at the molecular level in three experimental systems: a) in prokaryotes (ss M13mp19 lacZ'/E. coli F'lacZ delta M15); b) in eukaryotes (i) ss and ds pZ189 supF/CV1-P/E.coli lacZam and (ii) HPRT in CHO cells with different repair capacity. We think this type of approach can be used to study the genetic effects of new cancer drugs for which the molecular mechanisms of action at the molecular level are still not well understood. We think to apply the know-how to study mutational spectra in tumor derived tumor suppressor genes. 相似文献
9.
C H Hsu T W Kurtz H G Preuss J M Weller 《Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine (New York, N.Y.)》1975,149(2):470-472
The radioactive microsphere technique is a simple method for measurement of RBF and intrarenal blood flow distribution in the rat that does not require surgical manipulation of the kidney or general anesthesia. The results are reproducible and compatible with other established techniques. 相似文献
10.
The fact that the Corpora sesamoidea have never been precisely defined has led to a series of small cartilaginous bodies in the larynx being thus designated, for want of a better solution. Since the corpora sesamoidea have been identified as capsular bodies, however, originating in or in connection with a synovial capsule, there remained only one laryngeal cartilage which appeared to fulfill all the criteria of sesamoid cartilage, namely the papilionaceous cartilage found in all alar species from Monotremata to Carnivora, and which comparative anatomists term proarytaenoid cartilage. If Goeppert's findings are regarded as having an additional functional significance, then it is clear that this cartilage too, like cartilagines interarytaenoidea, postarytaenoidea (dorsoarytaenoidea in the dog?) pararytaenoidea, cunciformis, corniculata, intercorniculata and triticea, is a connecting cartilage. 相似文献