Studies on human endometrial cells in primary culture.
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Arachidonic Acids↗
Biomedical subjects
D Heller
Publications and source records attributed to D Heller.
Nitrosation of tertiary aromatic amines related to sunscreen ingredients.
Possible routes to the formation of the sunscreen contaminant, 2-ethylhexyl 4-N-methyl-N-nitrosoaminobenzoate, have been investigated in a study of the nitrosation chemistry of 2-ethylhexyl 4-N,N-dimethylaminobenzoate (Padimate-O) and related tertiary and secondary amines. Padimate-O and the corresponding ethyl ester nitrosate rapidly at 25 degrees C in either N2O3:ether or HNO2:HOAc to produce a mixture of alkyl 4-N-methyl-N-nitrosoaminobenzoate and alkyl 4-N,N-dimethylamino-3-nitrobenzoate, the former of which is the major product. The nitrosative dealkylation of these amines at this low temperature is unusual. Asymmetrical amines exhibit a preference for nitrosative demethylation (methyl versus ethyl or benzyl), but the cleavage ratios in N2O3:ether are time-dependent, suggesting competing mechanisms with different reactant kinetic orders. A radical cation route would explain the unusual reactivity, which may compete with the established nitrosative dealkylation mechanism. 2-Ethylhexyl 4-N-methyl-N-nitrosoaminobenzoate was mutagenic in two strains of Salmonella typhimurium in the Ames assay.
4-Aminobenzoic Acid↗
The proto-oncogene c-ros codes for a transmembrane tyrosine protein kinase sharing sequence and structural homology with sevenless protein of Drosophila melanogaster.
Our earlier study predicted that proto-oncogene c-ros codes for a receptor-like tyrosine protein kinase (TPK). To further understand its protein structure and physiological function, we have analysed its expression in various tissues of chicken and have isolated and sequenced cDNA clones containing the entire coding region of the gene. Confirming our earlier study, we found that kidney is the organ that expresses the highest level of c-ros mRNA, in addition, we found a lower level of expression in gonad, thymus, bursa and brain. A distinctive 8.3 kb c-ros mRNA is present in kidney. No detectable amount of c-ros mRNA was found in the rest of tissues examined. Nucleotide sequence of the c-ros cDNA predicts that it codes for a transmembrane (TM) TPK molecule of 2311 amino acids (aa). The extracellular domain consists of 1873 amino acids which share 20 to 43% homology with that of the Drosophila sevenless protein and TPK domains of the two genes have 58 to 74% homology. The extracellular domain containing 37 potential N-linked glycosylation sites is preceded by a 5' hydrophobic sequence resembling a typical signal peptide. An internal hydrophobic domain of 26 amino acids, the presumed transmembrane domain, is followed by a spacer sequence of 58 amino acids, a TPK domain of 270 amino acids and a carboxyl tail of 84 amino acids. Overall, our result indicates that c-ros codes for a glycosylated transmembrane TPK molecule which shares a remarkable sequence and structural homology with that of Drosophila sevenless protein.
Amino Acid Sequence↗
Interactive morphometry of normal and hyperplastic peritoneal mesothelial cells and dysplastic and malignant ovarian cells.
This study used computerized interactive morphometry to evaluate the differential characteristics of mesothelial normal cells, mesothelial hyperplastic cells, and carcinomatous cells, and also compared hyperplastic mesothelial cells with ovarian dysplastic cells from a previous study. The procedure included extraction of multiple descriptors of the nuclear profile: perimeter length, area, longest chord, circularity factors, standard deviations of these characteristics, and a 10-bin size distribution table of the nuclear area. The final classification is achieved by stepwise discriminant analysis of these variables. The analysis classified all cases correctly with high posterior probabilities.
Cystadenocarcinoma↗
Somatic diversification of chicken immunoglobulin light chains by point mutations.
The light-chain locus of chicken has 1 functional V lambda 1 gene, 1 J gene, and 25 pseudo-V lambda-genes (where V = variable and J = joining). A major problem is which somatic mechanisms expand this extremely limited germ-line information to generate many different antibodies. Weill's group [Reynaud, C. A., Anquez, V., Grimal, H. & Weill, J. C. (1987) Cell 48, 379-388] has shown that the pseudo-V lambda-genes diversify the rearranged V lambda 1 by gene conversion. Here we demonstrate that chicken light chains are further diversified by somatic point mutations and by V lambda 1-J flexible joining. Somatic point mutations were identified in the J and 3' noncoding DNA of rearranged light-chain genes of chicken. These regions were analyzed because point mutations in V lambda 1 are obscured by gene conversion; the J and 3' noncoding DNA are presented in one copy per haploid genome and are not subject to gene conversion. In rodents point mutations occur as frequently in the V-J coding regions as in the adjacent flanking DNA. Therefore, we conclude that somatic point mutations diversify the V lambda 1 of chicken. The frequency (0-1%) and distribution of the mutations (decreasing in number with increased distance from the V lambda 1 segment) in chicken were as observed in rodents. Sequence variability at the V lambda 1-J junctions could be attributed to imprecise joining of the V lambda 1 and J genes. The modification by gene conversion of rearranged V lambda 1 genes in the bursa was similar in chicken aged 3 months (9.5%) or 3 weeks (9.1%)--i.e., gene conversion that generates the preimmune repertoire in the bursa seems to level off around 3 weeks of age. This preimmune repertoire can be further diversified by somatic point mutations that presumably lead to the formation of antibodies with increased affinity. A segment with structural features of a matrix association region [(A + T)-rich and four topoisomerase II binding sites] was identified in the middle of the J-C lambda intron (where C = constant).
Animals↗
Infarction of intestine with massive amyloid deposition in two patients on long-term hemodialysis.
Two patients undergoing hemodialysis for 19 and 13 yr, respectively, developed intestinal infarction with extensive amyloid deposits in the muscle layer and blood vessels. In 1 patient the deposit reacted positively with antiserum to beta 2-microglobulin by immunohistochemical stain, and therefore was classified as beta 2-microglobulin in origin. The amyloid protein of the other patient remains unclassified. In patients with gastrointestinal symptoms who have been undergoing hemodialysis for long periods of time, amyloidosis of the intestine should be considered.
Amyloidosis↗
Prenatal diagnosis of fetal brain tumors.
Two cases of congenital brain tumors were detected during routine antepartum sonography at the Mount Sinai Medical Center Perinatal Ultrasound Unit. In both cases, diagnosis was made during the third trimester at 31 and 33 weeks, respectively. In one of these patients, no intracranial abnormalities were noted on a sonogram performed in conjunction with genetic amniocentesis at 18 weeks gestation. The histologic diagnosis of both tumors was glioblastoma multiforme grade III. Previous reports describing the prenatal sonographic diagnosis of intracranial tumors have been in cases with fetal intracranial teratomas.
Adult↗
An outbreak of gastrointestinal illness associated with consumption of raw depurated oysters.
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Disease Outbreaks↗
Transcriptional measurements of mouse repeated DNA sequences.
We have carried out transcriptional measurements on several families of repeated sequences to define their expression in mouse cells. The majority of Alu family transcripts result from read-through from adjacent structural gene promoters while 20% are discrete RNA polymerase III products. Alu repeat members show preferential orientation within RNA polymerase II transcription units as evidenced by asymmetric representation of the complementary strands of the Alu family in hnRNA. We assessed whether 3 non-Alu repeated sequence families had their own promoters by strand symmetry measurements and size distribution analysis of repeat-homologous newly synthesized nuclear RNA. Transcription homologous to the R family is totally symmetric and is likely due to read-through from adjacent structural gene promoters. LLRep1 and Bam5 repeats, in contrast, exhibit consistent strand asymmetry which is suggestive that at least some members may be transcribed by their own promoters. Among 3 mouse tissues and 1 cultured cell line analyzed, no quantitative variation in the expression of any of these sequences was observed.
Animals↗
Experimental coating of flexor tendons with polyvinylpyrrolidone to reduce postoperative adhesions.
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Animals↗
Organization and expression of non-Alu family interspersed repetitive DNA sequences in the mouse genome.
The mouse genome is complex with regard to DNA sequence organization and transcriptional activity. To more fully understand the role of interspersed repetitive DNA sequences we have isolated and characterized five different mouse non-Alu DNA sequence families. We have found that: (1) the distribution of repetitive sequences is non-random in the genome; (2) two of the five families (Bam5 and R) were previously described by Fanning (1982) and Gebhard et al. (1982), respectively. We found that these two families are linked to each other and are found adjacent to seven of seven studied structural genes but in randomly selected DNA fragments showed much less significant linkage. (3) The position of the Bam5 and R family repeat units relative to beta-globin and relative to a housekeeping gene has been evolutionarily conserved in mice and humans. (4) Three previously undescribed families representing from 200 to 40,000 copies per genome have been characterized and shown to have equivalent human sequences. (5) All five families studied are represented in RNA polymerase II transcripts. Little RNA polymerase III transcription homologous to these three families could be detected. The structural and functional features of these five families defined in this paper provide a basis for studies on the functional role of interspersed repetitive DNA in the mouse.
Animals↗
Position of ester groups in the lipid A backbone of lipopolysaccharides obtained from Salmonella typhimurium.
Lipopolysaccharides extracted from the heptoseless mutant of Salmonella typhimurium G30/C21 were hydrolyzed with either 0.1 N HCl at 100 degrees C or treated twice with 20 mM sodium acetate, pH 4.5, at 100 degrees C for 45 min and finally purified by preparative thin layer chromatography to yield a structural series of mono- and diphosphoryl lipid A, respectively. Positive ion fast atom bombardment mass spectrometry of the diphosphoryl lipid A TLC-3 (a highly acylated major band) showed a major component with (M + H)+ ion of mass 1798, which fragmented to yield a (M - H2PO4)+ ion of mass 1700. Cleavage at the glycosidic bond gave rise to an oxonium ion fragment of mass 1087. In conjunction with other studies, this establishes the molecular formula and Mr of the major component to be C94H178N2O25P2 and 1797.2 (as the free acid), respectively. Similar analysis of monophosphoryl lipid A TLC-3 produced an (M + H)+ peak at m/z 1718, (M + Na)+ adduct peak at m/z 1740, and a fragment of mass 1087. The spectrum of monophosphoryl lipid A TLC-5 was devoid of the m/z 1087 peak and instead contained the phosphorylated oxonium ion of mass 876. This fragment ion is assigned as the distal subunit, and these results show that the distal subunit of the major lipid A TLC-3 contains two hydroxymyristoyl, one myristoyl, and one lauroyl residues, whereas the reducing end subunit contains two hydroxymyristoyl groups. A revised structure of the lipid A backbone in lipopolysaccharides of S. typhimurium is proposed.
Chromatography, Thin Layer↗
N-acetylaspartylglutamate: an endogenous peptide with high affinity for a brain "glutamate" receptor.
A brain peptide with high affinity (420 nM) and marked specificity for brain receptor sites labeled with L-[3H]glutamate has been identified. Amino acid analysis and mass spectroscopy indicate that the peptide is N-acetylaspartylglutamate. The peptide exhibits potent convulsant properties when injected into the rat hippocampus, similar to those produced by the glutamate receptor agonist, quisqualic acid. These findings raise the question whether endogenous brain peptides enriched in acidic amino acids may serve as excitatory neurotransmitters.
Animals↗
Structural correlates of cellular tumorigenicity and anchorage independence in transformed fibroblasts.
The ability on nonhematopoietic cells to proliferate in vitro without attachment to a solid surface (anchorage independence) is known to be highly correlated with their ability to form tumors in nude mice. Transformed cells in vitro frequently also show less organization of the intracellular actin-containing microfilament bundles and less cell-surface fibronectin compared to normal cells. We have examined whether the loss of the anchorage requirement for growth is related to either of these structural changes in the cellular cytoskeleton. Our approach was to select a series of subclones from a nontransformed Syrian hamster fibroblast line, NIL8, for the acquisition of either anchorage independence in vitro or tumorigenicity in nude mice. These subclones were then examined for concomitant changes in the cytoskeletal structures. We found that anchorage independence, decreased actin cable organization, and tumorigenicity in nude mice were coordinately induced in both the in vitro- and in vivo-selected subclones, whereas the loss of fibronectin was not consistently coinduced with these three markers. These results suggest that the transformation-associated decrease in actin cable organization in this type of cell enhances the ability to grow without anchorage in vitro and to form tumors in vivo.
Actins↗
[Feeding for production in dairy animals].
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Animal Feed↗
Themes of culture and ancestry among children of concentration camp survivors.
Response to the most stressful of circumstances provides insight into the human capacity for adaptability. Survivors of catastrophic historical events, such as the Nazi Holocaust and the Atomic Holocaust of Hiroshima, provide evidence of individual and cultural resilience. Of particular interest is the impact of concentration camp atrocities. As Israeli statesman Abba Eban recounts: "Never in all of recorded history has any family of the human race been overwhelmed by such a wave of grief and havoc" (Eban 1961). Existing research repeatedly demonstrates that the massive trauma of concentration camp internment profoundly affects survivors for the rest of their lives (Eitinger and Strom 1973; Chodoff 1970; Eitinger 1957). In order to comprehend the long-term cultural implications of the experiences of survivors, investigation of the succeeding generation is essential. The effect on sensitivity to culture and ancestry among children of concentration camp survivors is likely to be substantial, but the full scope of this impact has yet to be determined. The purpose of the present study is to begin to examine this impact and describe the intergenerational response of a culture to extreme stress.
Adolescent↗
The effect of the thyroidal state on the immunological state of the chicken.
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Animals↗
Immune response to Newcastle disease virus vaccine, fowl-pox vaccine, and Escherichia coli vaccine in Bedouin and White Leghorn chickens.
Immune response to Newcastle disease virus (NDV) vaccine, fowl pox, and E. coli vaccine was compared in the native Bedouin fowl of the Sinai desert, in a commercial Leghorn layer strain, and in the reciprocal crosses between them. Differences were not found in antibody titer levels to attenuated or inactivated NDV vaccines, in the proportion of birds showing post-vaccination immunity to fowl pox, or in the kinetics of postvaccination NDV titer levels. Rate of development of titer to Escherichia coli from day 1 to day 4, however, was significantly more rapid in Bedouin chicks than in the purebred Leghorn or the reciprocal crosses.
Animals↗