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Biomedical subjects

I Klein

Publications and source records attributed to I Klein.

At least 199 records · Page 11Linked to original sources
PubMed1977

Cowpea mosaic virus RNAs have neither m7GpppN ... nor mono-, di- or triphosphates at their 5' ends.

32P-labeled cowpea mosaic virus (CPMV) RNAs were analyzed for their 5' termini by three different fingerprinting standard procedures. These analyses showed unequivocally that CPMV RNAs lack a structure like m7GpppN ... at their 5' termini. In addition, neither mono-, di- or triphosphorylated [(p)(p)pN ....] termini were found in the respective fingerprints. The inability to label the 5' termini treatment with gamma-32P-ATP and polynucleotide kinase, either per se or after pretreatment with alkaline phosphatase, strongly suggests the absence of a free 5'-OH and a free 5'-phosphate at the 5' terminal nucleotide in CPMV RNAs. The various analyses also showed that no 2' -O-methylated nucleotides, N6-methyladenosines or pseudo-uridines are present in CPMV RNAs.

Adenosine Triphosphate↗
PubMed1977

WAIS differences between murderers and attackers referred for evaluation.

12 first and second degree murderers were matched on sex and age with subjects who had perpetrated aggressive interpersonal attacks short of homicide. Both groups had been referred for psychological testing by courts and social agencies. A substantial and significant difference in IQ was found in favor of the attackers over the murderers. Results were interpreted as lending credence to the hypothesis that differences in IQ exist among important sub-populations of murderers.

Adult↗
PubMed1975

Occurrence of polyamines in coliphages T5, phiX174 and in phage-infected bacteria.

The polyamine spermidine and the diamine putrescine have been detected in coliphages T5 and phiX174. Polyamines were identified by thin-layer chromatography and mass-spectrometry of dansyl derivatives, as well as by ion-exchange chromatography. In phiX174 phages, polyamines were sufficient to neutralize 0.5% of DNA phosphates. The polyamine content of T5 phages depended on growth media and purification procedures, but at least 1% of DNA phosphates were neutralized by polyamines. After infection, an increase in cellular polyamine was noticed. This increase paralleled variations in ornithine decarboxylase activity.

Carboxy-Lyases↗
PubMed1975

Endogenous ethylene and abscisic Acid relative to phytogerontology.

Endogenous production of ethylene and endogenous levels of abscisic acid were measured from Hibiscus rosa-sinensis L. abscission zone explants at six stages of development: tight bud, open flower, closed flower, petal abscission, calyx abscission, and peduncle abscission.Explants acropetal and basipetal to the abscission zone produced less ethylene than the abscission zone explants. Ethylene production increased with time both prior to and during abscission, reaching a peak in the later stages of senescence after abscission was complete.Bound abscisic acid was greatest in segments acropetal to the abscission zone at the closed flower stage. Free abscisic acid was double that of bound abscisic acid in the tight bud stage with the basipetal level exceeding that of the acropetal level until flower closure. Acropetal-free abscisic acid began to rise at petal abscission increasing sharply to a peak at calyx abscission. Both free and bound abscisic acid were greatly reduced at peduncle abscission. A relationship of ethylene and abscisic acid to abscission and senescence appears to exist.

Journal Article↗
PubMed1975

Glucagon and adenylate cyclase: binding studies and requirements for activation.

Solubilization of myocardial adenylate cyclase abolished responsiveness to glucagon and catecholamines, two of the hormones which activate the membrane-bound enzyme. Adenylate cyclase freed of detergent by DEAE-cellulose chromatography continues to remain unresponsive to hormone stimulation. However, adding purified bovine brain phospholipids--phosphotidylserine and monophosphatidylinositol--restored responsiveness to glucagon and catecholamines, respectively. 125-i-glucagon binding appeared to be independent of phospholipid, since equal binding was observed in the presence or absence of detergent and in the presence or absence of phospholipids. Chromatography of the solubilized preparation on Sephadex G-100 WAS CHARACTERIZED BY 125-I-glucagon binding and fluoride-stimulatable adenylate cyclase activity appearing in the fractions consistent with the void volume, suggesting a molecular weight greater than 100,000 for the receptor-adenylate cyclase complex. Prior incubation of the binding peak with 125-I-glucagon and rechromatography of the bound glucagon on Sephadex G-100 shifted its elution to a later fraction consistent with a smaller-molecular-weight peak. The molecular weight of this material was 24,000 to 28,000, as determined by SDS polyacrylamide gel electrophoresis. The latter findings are consistent with a dissociable receptor site for glucagon on myocardial adenylate cyclase.

Adenylyl Cyclases↗