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Paul Johnson

Publications and source records attributed to Paul Johnson.

28 records · Page 2Linked to original sources
PubMed2004

Effects of central vasotocin and mesotocin manipulations on social behavior in male and female zebra finches.

Male and female zebra finches (Taeniopygia guttata; total n = 40) were fitted with chronic guide cannulae directed at the lateral ventricle and were tested for aggression, affiliation, and partner preference following infusions of mesotocin (MT), vasotocin (VT), their antagonists, and vehicle control. Aggressive behavior was tested in a mate competition paradigm and tests of intersexual affiliation and partner preference were conducted following 1 day of cohabitation with an opposite-sex individual. These tests also provided data on male courtship singing. The results demonstrate a modest dose-dependent facilitation of aggression by VT, but not MT, in both male and female finches. However, only males were sensitive to infusions of a vasopressin antagonist, suggesting that endogenous VT is more important for behavioral modulation in males. Peptide effects were specific to aggression, as no treatments influenced intersexual affiliation, partner preference, or male courtship singing. Thus, in contrast to rodents, partner preference is not readily induced by VT or MT in this species. However, the potential necessity of endogenous VT and MT for natural pair-bond formation remains to be tested.

Aggression↗
PubMed2004

'Wonderment and dread': representations of DNA in ethical disputes about forensic DNA databases.

The national DNA Database of England & Wales is the largest forensic DNA database in the world. Since 1995 it has quickly developed to hold the genetic profiles of over two million people. This collection of tissue samples, taken without consent from a sizeable collection of the population, has engendered a number of ethical commentaries on its legitimacy as a proportionate response to crime. This paper examines the ways in which the ethical discourses, which surround the uses of the National DNA Database, drew upon and deployed a number of distinct representations of DNA. It is argued that key ideas about DNA have become central to everyday assertions about the benefits and dangers of this forensic technology.

Biological Specimen Banks↗
PubMed2004

Circuits of Surveillance.

This paper examines the increasing police use of DNA profiling and databasing as a developing instrumentality of modern state surveillance. It briefly notes previously published work on a variety of surveillance technologies and their role in the governance of social action and social order. It then argues that there are important differences amongst the ways in which several such technologies construct and use identificatory artefacts, their orientations to human subjectivity, and their role in the governmentality of citizens and others. The paper then describes the novel and powerful form of bio-surveillance offered by DNA profiling and illustrates this by reference to an ongoing empirical study of the police uses of the UK National DNA Database for the investigation of crime. It is argued that DNA profiling and databasing enable the construction of a 'closed circuit' of surveillance of a defined population.

Journal Article↗
PubMed2003

Genetics and Forensics: Making the National DNA Database.

This paper is based on a current study of the growing police use of the epistemic authority of molecular biology for the identification of criminal suspects in support of crime investigation. It discusses the development of DNA profiling and the establishment and development of the UK National DNA Database (NDNAD) as an instance of the 'scientification of police work' (Ericson and Shearing 1986) in which the police uses of science and technology have a recursive effect on their future development. The NDNAD, owned by the Association of Chief Police Officers of England and Wales, is the first of its kind in the world and currently contains the genetic profiles of more than 2 million people. The paper provides a framework for the examination of this socio-technical innovation, begins to tease out the dense and compact history of the database and accounts for the way in which changes and developments across disparate scientific, governmental and policing contexts, have all contributed to the range of uses to which it is put.

Journal Article↗
PubMed2002

Recipient cells form the intimal proliferative lesion in the rat aortic model of allograft arteriosclerosis.

Chronic rejection is the leading cause of late graft loss following solid organ transplantation and is characterized by a vasculopathy referred to as allograft arteriosclerosis. While the etiology of allograft arteriosclerosis remains unknown, it has been hypothesized that migration of donor medial smooth muscle cells into the intimal compartment is responsible for the formation of the occlusive lesion (neointima). In this study we have used aortic interposition grafts between fully histoincompatible rat strains (Brown Norway and Lewis) to investigate the origin of the neointimal cells. Three transplant paradigms were used: BN to Lew, Lew to BN and BN to Lew with immunosuppression. Neointimal cells were isolated from aortic transplant tissue through an EDTA wash/mechanical stripping technique. We have developed polymerase chain reaction primers to the MHC1 allele that are specific to each rat strains' DNA. Polymerase chain reaction analysis, using the strain-specific primers and purified neointimal cell DNA from transplanted aortic tissue from all three experimental groups, demonstrated that the neointimal cells are of recipient, and not donor origin.

Animals↗
PubMed2002

Excitatory motor innervation in the canine rectoanal region: role of changing receptor populations.

1. Motor innervation in the canine rectoanal region was examined in isolated strips of the circular muscle layer. Contractile responses to electrical field stimulation began at lower frequencies and were more persistent in the internal anal sphincter (IAS) than in the rectum. 2. Motor innervation to the IAS was almost exclusively sympathetic, since it was blocked by guanethidine (Guan 3 microM) while the response in the proximal rectum was approximately 50% muscarinic, and sensitive to the M(3) selective antagonist 4-diphenylacetoxy-N-methylpiperidine (4-DAMP, 0.1 microM) and 50% tachykinergic, and sensitive to the neurokinin 2 (NK(2)) receptor antagonist GR 94800 (1 microM). From IAS to rectum there was a gradual shift in the relative contribution of intrinsic and extrinsic neural innervation. 3. Responses to exogenously applied transmitters exhibited a similar pattern to that observed with motor innervation. Norepinephrine (NE) was most potent in the IAS and acetylcholine (ACh) and NK-A were most potent in the proximal rectum. The responses were inhibited by prazosin, 4-DAMP and GR 94800 respectively. 4. A gradient in the density of adrenergic alpha(1), muscarinic and NK(2) receptors also existed from IAS to rectum as determined by measuring the binding of [(3)H]-prazosin, [(3)H]-quinuclidinyl benzilate ([(3)H]-QNB and [(3)H]-SR-48968 to smooth muscle membranes. 5. In summary, these data suggest that the shift in motor innervation in the rectoanal region is achieved in part by changes in receptor populations available for activation by sympathetic and enteric motor neurons.

Adrenergic alpha-1 Receptor Antagonists↗
PubMed1975

Mode of formulation of cholesta-5,7-dien-3beta-ol from Cholest-5-en-3beta-ol by Larvae of Calliphora erythrocephala.

1. The conversion of cholest-5-en-3beta-ol (cholesterol) into cholesta-5,7-dien-3beta-ol by axenic Calliphora erythrocephala larvae was demonstrated. 2. The transformation is probably direct (Delta(5)-->Delta(5,7)) and does not involve a Delta(0) intermediate (Delta(5)-->Delta(0)-->Delta(7)--> Delta(5,7)). 3. Delta(7)-bond formation involves the stereospecific elimination of the 7beta hydrogen atom. 4. The relative amounts of free and esterified sterols were determined in larvae grown on cholesterol as sole sterol source and on 5alpha-cholestan-3beta-ol supplemented with minimal amounts of cholesterol. 5. The significance of the results is assessed in relation to the probable role of cholesta-5,7-dien-3beta-ol as an intermediate in the biosynthesis of ecdysones.

Animals↗
PubMedDate not supplied

Branding an anatomic pathology practice to build revenue.

Innovative Pathology Services (IPS) is an Associate Practice of Pathology Service Associates (PSA). PSA is an organization known as the "Business Solution for Pathology." IPS provides pathology services to nine hospitals, including two large tertiary-care medical centers, a progressive and renowned children's hospital, a cancer survival center, five surgery centers, and numerous physician's offices and clinics throughout east Tennessee. We accept specimen referrals from other pathology practices and providers from across the country. The center of operations is in Knoxville, a mid-sized metropolitan district. Until January 1, 2003, we were known as Knoxville Pathology Group (KPG). We renamed our practice because KPG did not reflect our service area, was limiting by perception, barely distinguished us from other groups, and did not describe our culture and philosophy. IPS is a new name for a well-established pathology group with a solid foundation and a long history of providing services at the point-of-care. As such, we offer all services that we offered through our foundation practice, and, in addition, these services were enhanced and new services were added. Our entire "team" and, in particular, the pathologists, were involved in the successful "branding" of IPS. Whether you are an independent anatomic pathology or clinical laboratory or you are hospital based, you may benefit from our experiences detailed in this article.

Contract Services↗