PubMed Health⌕ Search

Biomedical subjects

W R Crain

Publications and source records attributed to W R Crain.

At least 37 records · Page 2Linked to original sources
PubMed1983

Cutaneous angiosarcoma resembling anaplastic Kaposi's sarcoma in a homosexual man.

A 46-year-old man presented with an unusual angiosarcoma of skin and urinary bladder, clinically suggestive of Kaposi's sarcoma (KS). Histologically, the pattern was that of an anaplastic angiosarcoma with only minimal regions considered characteristic of KS. It is suggested that this rare type of angiosarcoma may be closely related to, if not best classified as, an anaplastic variant of KS. The cutaneous lesions responded to intralesional vinblastine. The association of anaplastic angiosarcoma with homosexual sexual practices should be investigated along with those cases having the classical histologic characteristics of Kaposi's sarcoma.

Diagnosis, Differential↗
PubMed1983

Transcripts of paternal and maternal actin gene alleles are present in interspecific sea urchin embryo hybrids.

Analysis of actin-coding RNAs in interspecific hybrid sea urchin embryos of Strongylocentrotus purpuratus and Lytechinus variegatus, and S. purpuratus and S. droebachienis has revealed the presence of transcripts from both paternal and maternal S. purpuratus actin gene alleles. In the L. variegatus female X S. purpuratus male embryos transcripts from at least two different paternal actin gene alleles are present in both the blastula and prism stages. In the reciprocal S. purpuratus female X L. variegatus male embryos, the same two maternal (S. purpuratus) alleles were also expressed as RNA in blastula. The S. droebachiensis female X S. purpuratus male embryos appear to contain transcripts from at least one paternal actin gene allele at the blastula stage. The paternally derived actin-coding RNAs are the same size as the mature actin mRNAs expressed in normal S. purpuratus embryos. Since all known S. purpuratus actin genes contain at least two introns, the paternal alleles are not only transcribed in the hybrid embryos, but also the primary transcripts are probably processed to mature mRNA. An explanation of the diversity of observations in the literature on paternal genome expression in hybrid sea urchin embryos is discussed.

Actins↗
PubMed1983

Conserved pattern of embryonic actin gene expression in several sea urchins and a sand dollar.

An examination of the size and relative abundance of actin-coding RNA in embryos of four sea urchins (Strongylocentrotus purpuratus, Strongylocentrotus droebachiensis, Arbacia punctulata, Lytechinus variegatus) and one sand dollar (Echinarachnius parma) reveals a generally conserved program of expression. In each species the relative abundance of these sequences is low in early embryos and begins to rise during late cleavage or blastula stages. In the four sea urchins, actin-coding RNAs increase between approximately 9- and 35-fold by pluteus or an earlier stage, and in the sand dollar about 5.5-fold by blastula. A major actin-coding RNA class of 2.0-2.2 kilobases (kb) is found in each species. A smaller actin-coding RNA class, which accumulates during embryogenesis, is also present in S. purpuratus (1.8 kb), S. droebachiensis (1.9 kb), and A. punctulata (1.6 kb), but apparently absent in L. variegatus and E. parma. In S. droebachiensis, actin-coding RNA is relatively abundant in unfertilized eggs and drops sharply by the 16-cell stage. This is in contrast to the other sea urchins where the actin message content is relatively low in eggs and does not change substantially in the embryos throughout early cleavage. The observations in this study suggest that the pattern of embryonic expression of at least some members of this gene family is ancient and conserved.

Actins↗
PubMed1983

Topical carmustine (BCNU) for mycosis fungoides and related disorders: a 10-year experience.

A 10-year experience in eighty-six patients confirms the effectiveness of topical carmustine (BCNU) in mycosis fungoides (MF). Complete remission (CR) was achieved in 84% of those with less than 10% involvement (stage IA), median CR, 12 months, and in 52% with greater than 10% involvement (stage IB), median CR, 23 months. The probability of freedom from relapse for 1 year was 72% in stage IA and 37% in stage IB. No deaths in stages IA or IB were attributable to MF. Including all causes of death, the probability of 5-year survival for stage IA was 93% and for stage IB, 48%. Good results were obtained with only local BCNU in fourteen patients with mostly less than 5% involvement. Five of seven with poikilodermatous MF, two with parapsoriasis en plaques (PEP), and three with lymphomatoid papulosis did well. Persistent local therapy cleared deeply infiltrated lesions in some patients. With present schedules, the hazard of bone marrow depression is slight. Erythematous reactions and telangiectasia are troublesome but have not been accompanied by premalignant changes.

Administration, Topical↗
PubMed1982

Complete nucleotide sequence of a sea urchin actin gene.

We have determined the complete nucleotide sequence of a sea urchin actin gene, including the entire protein-coding sequence, introns and approximately 500 and 700 nucleotides adjacent to protein-coding-sequence on the 5' and 3' sides, respectively. This gene is split between codons 121 and 122 and within codon 204 by two introns which are 233 and 181 nucleotides in length, respectively. Comparison of the sequence of the two introns indicates a region of distant relatedness which covers about 25% of their lengths, suggesting that these sequences might have derived from a common ancestral sequence. The encoded amino acid sequence, which matches plasmic-like than muscle-like when compared to vertebrate actins. Analysis of the coding-flanking regions indicates the presence of sequences similar to those thought to be important for initiation of transcription and polyadenylation of mRNA. The location of these sequences and the size of an actin mRNA, transcribed from this or a very closely related gene, suggests that initiation occurs 347 nucleotides 5' of coding and polyadenylation approximately 515 nucleotides 3' of coding.

Actins↗
PubMed1981

Quantitative electron microscopic comparison of lymphocyte nuclear contours in mycosis fungoides and in benign infiltrates in skin.

Quantitative electron microscopy was used to measure lymphocyte nuclear contours in skin biopsies from 109 patients, 77 with benign disorders, 16 with early mycosis fungoides (MF), and 16 with controversial lesions. A nuclear contour index (NCI) was calculated on electron micrographs by dividing the nuclear profile circumference by the square root of the nuclear area. Significant differences were found between the group mean NCI for MF (NCI = 6.1 +/- 0.1) and for the benign group (NCI = 4.6 to 5.4 +/- 0.1; P less than 0.005). The group mean NCI for the controversial cases was significantly lower than that of the MF group (P less than 0.05). It is suggested that a definite electron microscopic diagnosis of MF requires first a patient mean NCI of 6.1 or more, and second, at least 6% of lymphocytes with an NCI of 9 or more. These criteria give a false positive rate of 3% in benign and controversial disorders and a 50% false negative rate for early MF. Only lymphocytes with an NCI of 16 or more appear specific for MF (or Sezary's syndrome), but are not found in all cases.

Aged↗
PubMed1981

Organization and expression of multiple actin genes in the sea urchin.

A set of at least 11 actin genes has been isolated from genomic recombinant deoxyribonucleic acid libraries of the sea urchin Strongylocentrotus purpuratus. Most of the isolates derive from a library which represents the genome of a single animal. There are at least five distinct types of sea urchin actin gene, some of which are represented by multiple copies in the genome. The actin gene types are distinguished by nonhomologous flanking sequences and intervening sequences, though the protein coding sequences appear in most cases to be quite similar. Eight of the 11 genes isolated have been recovered in lambda recombinants that contain two actin genes, linked at 5- to 9-kilobase distances. Restriction map overlaps suggest that the genome contains an array of at least three of these genes spaced over about 30 kilobases of deoxyribonucleic acid. In the linkage patterns observed, actin genes of diverse types were linked to each other. In early embryos, actin messenger ribonucleic acid (RNA) transcripts of 1.8 and 2.2 kilobases were found, and the longer of these transcripts was more prevalent in the maternal RNA of the egg. From RNA gel blot experiments, we conclude that the two transcripts derive from different actin gene types. Different repetitive sequences were located to either side of most of the actin genes, and in most observed cases the repeat sequences which were adjacent to actin genes of a given type were similar. The repeat sequences flanking the actin genes belonged to families which were transcribed, but those repeats in the neighborhood of the actin genes which have been investigated were not themselves represented in the stable RNAs of eggs or early embryos.

Actins↗
PubMed1981

Actin gene expression in developing sea urchin embryos.

We show that the synthesis of actin is regulated developmentally during early sea urchin embryogenesis and that the level of synthesis of this protein parallels the steady-state amounts of the actin messenger ribonucleic acids (RNA). An in vitro translation and RNA blotting analysis of embryo RNA from several stages of early development indicated that during the first 8 h after fertilization there was a low and relatively constant level of actin messenger RNA in the embryo. Between 8 and 13 h of development, the amount of actin messenger RNA began to increase both in the cytoplasm and on polysomes, and by 18 h the amounts of actin message per embryo had risen between approximately 10- and 25-fold in the cytoplasm and between 15- and 40-fold on polysomes. Two size classes of actin messenger RNA (2.2 and 1.8 kilobases) were identified in unfertilized eggs and in all of the developmental stages examined. The amount of each actin message class increased over a similar time interval during early development. However, the amounts of these size classes in the cytoplasm relative to each other shifted between the earliest stages examined (2 to 5 h) and the hatching blastula stage (18 h), with the ratio of the 1.8-kilobase actin messenger RNA to the 2.2-kilobase actin messenger RNA increasing almost threefold during this period.

Actins↗
PubMed1981

Mycosis fungoides: diagnostic criteria based on quantitative electron microscopy.

Quantitative electron microscopy can provide objective measurements of nuclear atypia in lymphoid cells in skin biopsies during early stages of infiltration of the skin as part of inflammatory or neoplastic processes. This potentially provides a method for establishing reproducible criteria for determining whether an individual skin biopsy represents mycosis fungoides or is unlikely to represent mycosis fungoides. To investigate such criteria, quantitative electron microscopic studies of skin biopsies from 109 patients were performed. Seventy-seven patients had benign disorders, 16 patients had early mycosis fungoides, and 16 patients had controversial lesions. Measurements were made of lymphocyte nuclear profile perimeter and areas in electron micrographs. A nuclear contour index was calculated. On the basis of the mean degree of nuclear convolution alone, mycosis fungoides was not adequately distinguished from benign disorders. Better discrimination was achieved when the proportion of cells with a anuclear contour index of 9.0 or more was considered as an additional actor. When statistical methods were used to select discriminating factors, the best electron microscopic discrimination between benign and mycosis fungoides groups occurred when the proportion of cells with a nuclear contour index of 7 or more and the proportion of cells with a nuclear profile area greater than 30 sq. micrometer. were used together. Nomograms are presented which demonstrate the use of these criteria for a given case.

Aged↗
PubMed1980

Organization of actin gene sequences in the sea urchin: molecular cloning of an intron-containing DNA sequence coding for a cytoplasmic actin.

Southern transfer and solution hybridization experiments, using as probe a DNA fragment that encodes for Drosophila actin, demonstrate cross hybridization to DNA from the sea urchin Strongylocentrotus purpuratus. Recombinant DNA clones that contained sea urchin genomic DNA fragments were constructed and screened for the presence of actin-encoding DNA sequences by colony hybridization with the Drosophila actin sequence. Two different putative actin-encoding clones were identified and were shown to specifically hybridize actin-encoding mRNA from a complex mRNA population. Southern blot hybridization experiments with both the Drosophila actin sequence and one of the cloned sea urchin sequences, in conjunction with solution hybridization data, suggest an actin gene copy number of 5-20 per haploid genome. DNA sequence analysis of one of the cloned sequences indicates that this fragment codes for a cytoplasmic form of actin and contains an intervening sequence of at least 200 nucleotides beginning immediately after amino acid 121 in the protein sequence.

Actins↗
PubMed1976

Contrasting patterns of DNA sequence arrangement in Apis mellifera (honeybee) and Musca domestica (housefly).

We have examined the organization of the repeated and single copy DNA sequences in the genomes of two insects, the honeybee (Apis mellifera) and the housefly (Musca domestica). Analysis of the reassociation kinetics of honeybee DNA fragments 330 and 2,200 nucleotides long shows that approximately 90% of both size fragments is composed entirely of non-repeated sequences. Thus honeybee DNA contains few or no repeated sequences interspersed with nonrepeated sequences at a distance of less than a few thousand nucleotides. On the other hand, the reassociation kinetics of housefly DNA fragments 250 and 2,000 nucleotides long indicates that less than 15% of the longer fragments are composed entirely of single copy sequences. A large fraction of the housefly DNA therefore contains repeated sequences spaced less than a few thousand nucleotides apart. Reassociated repetitive DNA from the housefly was treated with S1 nuclease and sized on agarose A-50. The S1 resistant sequences have a bimodal distribution of lengths. Thirty-three percent is greater than 1,500 nucleotide pairs, and 67% has an average size about 300 nucleotide pairs. The genome of the housefly appears to have at least 70% of its DNA arranged as short repeats interspersed with single copy sequences in a pattern qualitatively similar to that of most eukaryotic genomes.

Animals↗
PubMed1976

Absence of short period interspersion of repetitive and non-repetitive sequences in the DNA of Drosophila melanogaster.

A sensitive search has been made in Drosophila melanogaster DNA for short repetitive sequences interspersed with single copy sequences. Five kinds of measurements all yield the conclusion that there are few short repetitive sequences in this genome: () Comparison of the kinetics of reassociation of short (360 nucleotide) and long (1,830 nucleotide) fragments of DNA; 2) reassociation kinetics of long fragments (2,200 nucleotide) with an excess of short (390 short nucleotide) fragments; 3) measurement of the size of S1 nuclease resistant reassociated repeated sequences; 4) measurement of the hyperchromicity of reassociated repetive fragments as a function of length; 5) direct assay by kinetics of reassociation of the amount of single copy sequence present on 1,200 nucletodie long fragments which also contain repetitive sequences.

Animals↗
PubMed1976

Template restriction in human chromatin.

DNA-dependent RNA polymerase from Escherchia coli was used to transcribe chromatin from human leukocytes and purified human DNA. RNA was labeled at the 5' terminus with either [gamma-32P]ATP or [gamma-32P]GTP and internally with [3H]UTP. Determination of the average chain length of the RNA molecules by the ratio of moles of 3H-labeled nucleotide incorporated to moles 32P-labeled nucleotide incorporated showed that the size of the transcript of purified DNA was about 2 1/2 times greater than those from chromatin. The percentage of chains initiated with ATP and GTP was observed to vary with the template, the ATP to GTP ratio being greater on chromatin. The kinetics of 3H and 32P hybridization of transcripts of purified DNA showed hybridization primarily to nonrepetitive sequences. Transcripts from the chromatin templates when hybridized to DNA showed a larger proportion of RNase resistance of the 32P-termini at low Cot's.

Chromatin↗
PubMed1976

DNA sequence organization in the lepidopteran Antheraea pernyi.

A large fraction of the genome of the lepidopteran Antheraea pernyi consists of interspersed single-copy sequences and repetitive DNA sequences of 300 nucleotide average length. Most of the single-copy sequences are about 800 nucleotides long and a minority are considerably longer. Thus, the organization of the DNA sequences of this insect is similar to that of most higher organisms and different from that of Drosophila.

Animals↗
PubMed1975

DNA sequence organization in the genomes of five marine invertebrates.

The arrangement of repetitive and non-repetitive sequence was studied in the genomic DNA of the oyster (Crassostrea virginica), the surf clam (Spisula solidissima), the horseshoe crab (Limulus polyphemus), a nemertean worm (Cerebratulus lacteus) and a jelly-fish (Aurelia aurita). Except for the jellyfish these animals belong to the protostomial branch of animal evolution, for which little information regarding DNA sequence organization has previously been available. The reassociation kinetics of short (250-300 nucleotide) and long (2,000-3,000 nucleotide) DNA fragments was studied by the hydroxyapatite method. It was shown that in each case a major fraction of the DNA consists of single copy sequences less than about 3,000 nucleotides in length, interspersed with short repetitive sequences. The lengths of the repetitive sequences were estimated by optical hyperchromicity and S1 nuclease measurements made on renaturation products. All the genomes studied include a prominent fraction of interspersed repetitive sequences about 300 nucleotides in length, as well as longer repetitive sequence regions.

Animals↗