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Biomedical subjects

D L Rock

Publications and source records attributed to D L Rock.

90 records · Page 5Linked to original sources
PubMed1986

Detection of bovine herpesvirus type 1 RNA in trigeminal ganglia of latently infected rabbits by in situ hybridization.

At times after conjunctival inoculation with bovine herpesvirus type 1 (BHV-1), representing the acute and latent phases of infection, rabbit trigeminal ganglia were examined for the presence of BHV-1 nucleic acids by in situ hybridization using a 3H-labelled BHV-1 DNA probe. During the acute phase of virus infection, both BHV-1 DNA and RNA were detected in ganglionic neurons and occasionally in adjacent satellite cells. However, during the latent phase of infection only viral RNA was detectable in involved neurons. Viral RNA appeared restricted to the nucleus of latently infected cells and was present in varying amounts in individual cells. These results indicate that the BHV-1 genome is transcriptionally active in ganglionic neurons during latent infection.

Animals↗
PubMed1985

Studies on the pathogenesis of a bovine cytomegalo-like virus in an experimental host.

Herpesvirus Movar 33/63 is the prototype strain of a group of slow growth bovine herpesviruses which have been reported to exhibit cytomegalovirus-like characteristics. These viruses have the ability to produce long-term persistent infections of spleen and other lymphoreticular organs in both cattle and rabbits. Rabbits were inoculated with a suspension of Movar 33/63 propagated in cell culture, and sacrificed at intervals between 3 days and 49 weeks post-infection. Cell-free infectious virus was detected only in conjunctival secretions, buffy coat and spleen homogenates up to 7 days post-infection. Beyond this brief acute replication period, co-cultivation or explantation was required for the detection of viral infectivity. The spleen, the only organ from which virus was consistently recovered, exhibited the highest infectious titres as detected by infectious centre assay. The use of several cell isolation techniques (including solid-phase fractionation on ligand-coated surfaces, nylon wool filtration, affinity chromatography, immunocytolysis and plastic surface adherence) allowed separation of B-enriched, T-enriched and non-T, non-B cell fractions. Infectivity during the acute and persistent phase of the infection was associated with the non-T, non-B population which was highly enriched in adherent and non-adherent spleen mononuclear phagocytes. No virus was isolated from either T or B cells.

Animals↗
PubMed1985

Comparative usefulness of tissue fixatives for in situ viral nucleic acid hybridization.

Traditionally tissues for in situ hybridization of viral nucleic acid have been small pieces obtained from laboratory rodents, and fixatives that are designed for electron microscopy, such as periodate-lysine-paraformaldehyde (PLP) can handle them adequately. However, these fixatives have limited penetrating ability and may produce no appreciable hardening, so alternative fixation methods were evaluated. The intention was to determine whether fixatives adequate for bulky tissues such as whole or halved pig and cow brains would also be compatible with in situ hybridization. Various fixatives were evaluated using a system of intracranial inoculation of BALB/c mice with pseudorabies virus (PRV) followed by in situ hybridization of brain tissue sections with a 35S-labeled PRV DNA probe. Loss of tissue sections was a major problem, particularly with PLP and formalin, but positive results were obtained with five fixatives tested. Cellular morphology was especially good with PLP and with a modification of Carnoy's fluid, MOCA fixative. An incidental but important observation was that formalin is compatible with in situ hybridization. Retroactive studies of viral diseases using routinely processed blocks of tissue (formalin-fixed, paraffin-embedded) are therefore conceivable.

Acetates↗
PubMed1984

Social support and social network scales: a psychometric review.

Social support and social network scales were reviewed from a psychometric perspective. A sample of 29 behavioral science studies were selected from social support and social network articles published between 1967 and 1982. Each study was classified according to psychometric issues of scaling, reliability, and validity. The review was motivated by the hypothesis that many social support and social network scales are developed without complete utilization of existing measurement technology. Results of this review confirm this hypothesis. Limited availability of basic psychometric data for such scales attenuates theory development and research efficiency. Researchers in this field are encouraged to increase the availability of basic psychometric information for social support and social network scales.

Humans↗
PubMed1984

Co-cultivation versus blot hybridization for the detection of trigeminal ganglionic latency following corneal inoculation with HSV-1 strains of varying TK expression and pathogenicity.

The sensitivity of two methods for the detection of latent trigeminal ganglionic (TG) infections were compared: (1) co-cultivation which detects infectious virions, and (2) blot hybridization which detects HSV-1 DNA sequences. Adult New Zealand rabbits were inoculated following corneal scarification with three strains of HSV-1 which differed in their thymidine kinase expression, and in their ability to invade the CNS and establish latency. When a large volume load of latent TG virus was expected (NIH TK+ strain), co-cultivation and blot hybridization were equally effective in detecting latent virus. However, when a small volume load of latent virus was expected (NIH TK+/-, NIH TK-), co-cultivation with its inherent amplification proved superior to blot hybridization for the detection of latent virus.

Animals↗
PubMed1984

Localization of herpes simplex virus in the trigeminal and olfactory systems of the mouse central nervous system during acute and latent infections by in situ hybridization.

The precise anatomical location of latent herpes simplex virus (HSV) infection of the mouse central nervous system (CNS) has been identified by application of a 3H-labeled HSV-specific probe to deparaffinized sections of mouse brain tissue in situ. At times after corneal inoculation with HSV type 1 (HSV-1), strain F, representing the acute and latent phases of infection, BALB/c mice were perfused with a fixative containing sodium m-periodate, lysine, and paraformaldehyde and their CNS tissues and trigeminal ganglia embedded in paraffin, sectioned, and and subjected to hybridization. During the acute phase, HSV-1 was localized to neurons and some small supporting cells in the sensory portion of the 5th cranial nerve including the trigeminal ganglia and nerve root, principal sensory nucleus, mesencephalic nucleus, descending tract and nuclei, and cerebral cortex. During the latent phase, HSV-1 was found only in neurons located primarily in the descending nuclei and mesencephalic nucleus. Evidence was also obtained that implicated the olfactory tract as an additional route of entry into the CNS, in that positive hybridization was found in the olfactory bulb, the entorhinal cortex, and adjacent cerebral cortex. Additionally, HSV-1 established latent infections in neurons of the olfactory system. HSV-1-specific RNA was detected in ganglionic and CNS neurons throughout the acute and latent phases of infection, whereas HSV-1-specific DNA was detected only during the acute phase, indicating that the relationship between HSV and latently infected CNS and ganglionic neurons involves limited transcription of the viral genome.

Acute Disease↗
PubMed1984

Measuring functional impairment associated with pain: psychometric analysis of an exploratory scoring protocol for activity pattern indicators.

Behavioral science theorists who study pain have advocated the development of measures designed to assess aspects of behavior. Recently, Diller , Fordyce , Jacobs, and Brown developed a 64-item self-report activity measure. Assessment of functional impairment associated with pain is a potentially appropriate application for the Activity Pattern Indicators (API). The API provides a description of actual functioning; frequency of behavior is the unit of measurement. Currently, no agreed upon scoring protocol is available for this measure. We propose to design, in accordance with measurement theory, a psychometrically sound yet practical scoring protocol. The API data presented allow an acceptable degree of reliability and sensitivity to group differences. Results of the present study support continued psychometric exploration of: the current scoring protocol, alternative scoring protocols, and the Activity Pattern Indicators.

Activities of Daily Living↗
PubMed1983

Detection of HSV-1 genome in central nervous system of latently infected mice.

Herpes simplex virus type 1 (HSV-1) can establish latent infections in peripheral nerve ganglia and the central nervous system (CNS) of experimentally infected mice. Latent infections of peripheral nervous tissue are characterized by the ability to recover infectious virus from explant cultures of most of the latently infected ganglia. In contrast, infectious virus is infrequently recovered from the CNS of latently infected mice following explant culture, although viral DNA can be detected in CNS tissue. The presence of incomplete or defective viral genomes during the latent CNS infections has been proposed to explain this difference between the two latent infections. To characterize the completeness and the physical state of the latent viral genome, we used Southern blot hybridization to analyse the viral DNA from latently infected mouse ganglia and brains. Our results, reported here, indicate that most, if not all, of the HSV-1 genome is present in latently infected CNS tissue and that the latent viral genome exists in a form other than linear, unit length DNA.

Animals↗
PubMed1982

Experimental infection of rabbits with bovine herpesvirus-4: acute and persistent infection.

A strain of bovine herpesvirus-4 (BHV-4) isolated from bovine cases of mammary pustular dermatitis was used for experimental infection of rabbits. The strain is serologically indistinguishable from the group prototype Movar 33/63 and from the American isolate DN599. Groups of rabbits were inoculated by various routes. Intravaginal and conjunctival inoculations resulted in vulvovaginitis and conjunctivitis, respectively, and in shedding of virus. The rabbits seroconverted for the virus, with high titers of antibodies (indirect fluorescent antibody test) that persisted throughout the experiment. Treatment with dexamethasone, beyond the acute infection, did not produce recrudescence of disease or shedding of the virus. Rabbits were killed at various times, from 3 to 6 months post-infection, and the virus was recovered from explant cultures of spleen and by cocultivation of spleen cells with bovine lung cells. These results demonstrate the usefulness of the rabbit as a model for studying the pathogenesis of BHV-4 infection in cattle.

Animals↗
PubMed1982

Persistent infection with bovine herpesvirus type 1: rabbit model.

Persistent infection with bovine herpesvirus type 1 (BHV-1) was established in all rabbits after conjunctival inoculation of virus. Spontaneous reactivations of BHV-1 with and without the appearance of recurrent ocular lesions were observed in persistently infected rabbits. BHV-1 was reactivated predictably and shed from all persistently infected rabbits after the administration of dexamethasone. During all reactivations, BHV-1 isolation was restricted to the inoculated eye.

Animals↗
PubMed1982

Comparison of the standard and computerized versions of the Raven Coloured Progressive Matrices Test.

Computerized psychological assessment is potentially a viable alternative to the traditional method of examiner based assessment. 15 children, 4 females and 11 males, ranging in age from 7 to 14 yr., were administered a computerized version of the Raven's Coloured Progressive Matrices test. The necessary software for computerizing this test was developed and programmed for use with an Apple II Plus microcomputer. Scores obtained from the computerized and traditional versions of the Raven's test were compared on total mean score, correlation with the WISC-R, Raven's subscale intercorrelations, and Raven's total mean score composition. In general, results indicate that the two versions of the Raven's Matrices do not statistically significantly differ on the dimensions tested in the present study. The relatively small number of subjects and the lack of rigorous experimental control limit generalization of the results. Continued research into the use of computerized psychological assessment is warranted.

Adolescent↗
PubMed1980

Persistence of pseudorabies virus in infected swine.

The persistence of pseudorabies virus (PRV) in pigs clinically recovered from the disease was detected by culture of tissue fragments. Weanling pigs were infected by intranasal instillation of 200,000 plaque-forming units of a strain of PRV isolated from sick pigs in Iowa, and virus was recovered from them 6 weeks to 13 months later. Tonsil, trigeminal ganglia, or pooled trigeminal ganglia and olfactory and optic nerve tissue were most consistently the source of virus. The tissue-fragment culture technique was compared with a co-culture technique for detection of virus in tissue specimens from the recovered pigs. Use of these procedures provided the means to detect PRV in pigs for periods longer than previously recognized.

Animals↗