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Biomedical subjects

J McCloskey

Publications and source records attributed to J McCloskey.

11 recordsLinked to original sources
PubMed1988

New function of vitamin B12: cobamide-dependent reduction of epoxyqueuosine to queuosine in tRNAs of Escherichia coli and Salmonella typhimurium.

Queuosine (Q), 7-[(4,5-cis-dihydroxy-2-cyclopentene-1-yl)-amino)methyl)-7- deazaguanosine, and Q derivatives usually replace guanosine in the anticodon of tRNAs(GUN) of eubacteria and of cytoplasmic and mitochondrial tRNAs of lower and higher eucaryotes except yeasts. Q appears to be synthesized de novo exclusively in eubacteria, and the free-base queuine serves as a nutrient factor for eucaryotes. Recently, a Q derivative, oQ, containing a 2,3-epoxy-4,5-dihydroxycyclopentane ring, has been identified in Escherichia coli tRNA(Tyr). Here we show that oQ is formed when E. coli or Salmonella typhimurium is grown in glucose-salt medium. The formation of oQ was independent of molecular oxygen, and oQ-tRNAs were converted to Q-tRNAs by adding cobalamin to the growth medium. Under strictly anaerobic conditions, considerable amounts of Q were present in E. coli and S. typhimurium tRNAs when the bacteria were grown in the presence of cobalt ions with glycerol as the carbon source and fumarate as the electron acceptor. Under these conditions, the biosynthesis of cobalamin was induced. The results suggest that oQ is derived from ribose and that oQ is finally reduced to Q by a cobamide-dependent enzyme.

Aerobiosis↗
PubMed1978

The effect of positive end-expiratory pressure (PEEP) ventilation in neurogenic pulmonary oedema. Report of a case.

The effect of positive end-expired pressure ventilation (PEEP) on mean systemic arterial pressure, mean pulmonary arterial pressure, mean pulmonary wedge pressure, mean intracranial pressure (ICP), and cerebral perfusion pressure (CPP), in a case of neurogenic pulmonary oedema (NPO) is presented. PEEP improved oxygenation, reduced, and finally stopped clinical pulmonary oedema. In this patient PEEP produced severe systemic hypotension. As a consequence of this, CPP was impaired.

Adult↗
PubMed1976

Early experience with total knee arthroplasty.

Early results of 76 geometric total knee replacements were reviewed with assistance from computer analysis. A 92% patient follow-up for one to three years showed an overall satisfactory result with substantial improvement, especially in relief of severe pain. However, several problems are noted, including fractures beneath the tibial plateau and loosening. The long-term results are still unknown. The indications for total knee replacements should remain conservative until long-term results and experience have been achieved.

Age Factors↗
PubMed1976

Cariogenesis.

Explore the source record for details and available documents.

Dental Caries↗
PubMed1975

Nucleotide sequence of U-2 ribonucleic acid. The sequence of the 5'-terminal oligonucleotide.

The nucleotide sequences were determined for the 5'-oligonucleotides obtained by complete pancreatic RNase digestion (P25) and complete T1 RNase digestion (T27) of U-2 RNA. Complete digestion of oligonucleotide P25 with snake venom phosphodiesterase produced pm3 2,2,7G, pAm, pUm, and pCp in approximately equimolar ratios. Partial digestion of these oligonucleotides with snake venom phosphodiesterase produced -Um-C-Gp and pAm-Um, indicating the sequence of the 3'-terminal portion of the 5'-oligonucleotide is pAm-Um-C-Gp. The 5'-terminal oligonucleotide did not contain a 5'-phosphate and no free nucleoside was released from the 5' end by venom phosphodiesterase digestion. Since free pm3 2,2,7G was released by digestion with nucleotide pyrophosphatase and limited digestion with snake venom phosphodiesterase, this nucleotide is apparently linked to pAm in a pyrophosphate linkage. Mass spectrometry and thin layer chromatography in borate systems showed the ribose of m3 2, 2, 7G contains no 2'O-methyl residue. Moreover, the finding that the ribose of m3 2, 2, 7G was oxidized by NaIO4 and reduced by KB3H4 in intact U-2 RNA rules out other linkages involving the 2' and 3' positions. Accordingly, it is concluded that the structure of the 5'-terminal pentanucleotide of U-2 RNA is(see article).

Alkaline Phosphatase↗
PubMedDate not supplied

Genetic marker analysis in cases of disputed paternity when the alleged father is deceased.

Data are presented to demonstrate the utility of genetic marker analysis in cases of disputed paternity in which the alleged father is deceased prior to testing. The first case involves the histocompatibility (HLA) typing of the alleged father's parents and presumed mother and child, in which the deceased alleged father (AF) was not excluded from paternity. The second case involves a similar situation. However, the deceased AF was not clearly excluded from paternity in the HLA system owing to the inability to rule out gene suppression or deletion, but the deceased AF was excluded following red blood cell antigen typing of the man's parents. These two cases demonstrate the utility of genetic marker analysis in cases of disputed paternity in which the AF is deceased. This same type of analysis can be applied to cases in which the presumed mother is either deceased or missing and custody of the child is being sought by the alleged father.

Erythrocytes↗
PubMedDate not supplied

Job satisfaction among Jordanian registered nurses.

In a nationwide survey, factors contributing to job satisfaction and dissatisfaction among Jordanian nurses were examined. Questionnaires were completed by 312 Jordanian staff nurses working in army, government, and private hospitals. The results revealed the Jordanian staff nurses were somewhat satisfied with their social and safety rewards and incentives but somewhat dissatisfied with their psychological rewards and incentives as offered to them by their hospital work settings.

Adult↗