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Biomedical subjects

J McCoy

Publications and source records attributed to J McCoy.

At least 37 records · Page 2Linked to original sources
PubMed1987

Molecular characterization of a polymerase mutant human immunodeficiency virus.

A cell line (8E5) containing a single defective copy of human immunodeficiency virus proviral DNA and producing noninfectious viral particles lacking reverse transcriptase (RT) and endonuclease proteins has recently been described (Folks, et al., (1986b) J. Exp. Med. 164, 280-290). In this report, the mutation in a full-length molecular clone of the provirus (p8E5) was mapped to a 1931-bp region of the pol gene encoding RT. The nucleotide sequence of this segment revealed a 1-base deletion 301 codons from the common amino terminus of the 64- and 51-kDa RTs. Expression of the p8E5 RT segment in Escherichia coli generated an enzymatically inactive and truncated 33-kDa protein.

Amino Acid Sequence↗
PubMed1985

Caution: leases can hide dangerous curves and clauses.

Leasing medical equipment can be a financially advantageous undertaking, but also somewhat risky. Leases, if misrepresented by the leasing company, can trap the healthcare organization into an agreement that is actually more costly than purchasing the equipment. Therefore, extreme caution should be taken when evaluating leasing agreements, looking carefully at each individual section of the lease for possible "hooks" and misrepresentations.

Contract Services↗
PubMed1981

The bacteriorhodopsin gene.

The bacteriorhodopsin gene has been identified in a 5.3-kilobase restriction endonuclease fragment isolated from Halobacterium halobium DNA, using a cloned cDNA fragment as the probe. Of the 1229 nucleotides whose sequence was determined in the genomic fragment, 786 correspond to the structural gene of bacteriorhodopsin, 360 are upstream from the initiator methionine codon, and 83 are downstream from the COOH terminus. The bacteriorhodopsin gene codes for a precursor sequence of 13 amino acids at the NH2 terminus, 248 amino acids that are present in the mature protein and an additional aspartic acid at the COOH terminus. This determination of the DNA sequence for an archaebacterial gene reveals that the standard genetic code is used; however, there is a marked preference for either G or C in the third codon position. The gene does not contain any intervening sequences and no prokaryotic promoter can be identified in the region immediately upstream from the structural gene. The bacteriorhodopsin mRNA contains at the 5' terminus only three nucleotides beyond the initiating AUG codon and this terminus can form a hairpin structure. Immediately downstream from this structure there is a sequence complementary to the 3' terminus of H. halobium 16S rRNA.

Amino Acid Sequence↗
PubMed1978

Instrumental removal of retained stones after choledochotomy.

Despite the widespread use of operative cholangiography and choledoschoscopy, stones are still left behind after exploration of the common bile duct. Reoperation is associated with a significant morbidity and mortality. The use of a steerable catheter-basket technique has enabled stones to be removed from the biliary tract in the vast majority of cases without significant complications and has practically eliminated the need for further surgery.

Adult↗
PubMed1976

Canine airway responses to acetylcholine, prostaglandin F2alpha, histamine, and serotonin after chronic antigen exposure.

Dose-response curves were obtained for aerosols of acetylcholine (ACh), prostaglandin F2alpha (PGF2alpha), histamine (H), and 5-hydroxytryptamine (5-HT) on pulmonary resistance (Rp) and dynamic lung compliance (Cdyn) in Ascaris-hypersensitive dogs. Previously, these animals had been subjected to chronic biweekly "allergic asthmatic" episodes by aerosol administration of Ascaris antigen. When examined either one week before or after antigen provocation the airways were not hyperreactive to ACh, H, or 5-HT but did demonstrate a modest hyperreactivity to PGF2alpha. When aerosol dose-response curves were obtained for these agonists immediately following an "allergic asthmatic" episode, the airways were hyporeactive to PGF2alpha, H, and 5-HT, but not to ACh. Studies with atropine indicated that the hyporeactivity was the result of decreased airway responsiveness to both direct and indirect effect of PGF2alpha and H. It is concluded that, in dogs, chronic antigen challenge is not accompanied by a general increase in airway reactivity to pharmacologic agents.

Acetylcholine↗
PubMed1976

Hodgkin's disease in siblings: a family study.

Hodgkin's disease may sporadically occur in more than one member of a family. A family in which two siblings were documented to have the nodular sclerosing form of the disease was studied for immunological competency, distribution of HL-A antigens, and Epstein-Barr virus (EBV) antibody titers. All family members examined, except the living individual with HD, had no significant abnormality in humoral and cellular immunity. HL-A antigens previously reported to appear in Hodgkin's disease with increased frequency were not found. Antibody titers to the viral capsid antigen of EBV were normal. Therefore, none of the genetically associated laboratory tests related to cancer (particularly Hodgkin's disease) were found in this family. The evidence from this family thus supports the probable importance of environmental factors in the etiology of Hodgkin's disease, particularly in the nodular sclerosis group.

Adolescent↗