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D L Rock

Publications and source records attributed to D L Rock.

At least 19 recordsLinked to original sources
PubMed1995

Analysis of 43 kb of the Chlorella virus PBCV-1 330-kb genome: map positions 45 to 88.

Forty-three kb of DNA, located at the left end (45 to 88 kb) of the 330-kb Chlorella virus PBCV-1 genome, was sequenced and analyzed. Eighty-six open reading frames (ORFs) 65 codons or longer were identified; 47 were classified as major ORFs. These 47 major ORFs are densely packed on both strands of PBCV-1 DNA. Seventeen of these major ORFs resemble genes in the sequence databases, including three putative gene products involved in manipulating sugars (glucosamine synthetase, GDP-D-mannose dehydratase, and N-acetylglucosaminyltransferase), two transcription factors, beta-1,3-glucanase, aspartate transcarbamylase, ubiquitin carboxy terminal hydrolase, RNA guanyl transferase, an exonuclease, and a helicase. This is the first time some of these putative PBCV-1 genes have been found in a virus genome. One of the transcription factor-like genes contains a type IB self-splicing intron. Since a spliceosomal processed intron was reported previously in the PBCV-1 DNA polymerase gene, PBCV-1 is the first virus known to contain two different types of introns.

Amino Acid Sequence↗
PubMed1995

Analysis of 45 kb of DNA located at the left end of the chlorella virus PBCV-1 genome.

Forty-five kilobases of DNA, including the previously sequenced 2.2-kb inverted repeat region, located at the left termini of the 330-kb Chlorella virus PBCV-1 genome were sequenced and analyzed. Eighty-five complete open reading frames (ORFs) larger than 195 nucleotides were identified. Thirty-seven of the 85 ORFs, which are densely packed on both strands of the DNA, were considered major ORFs. Fifteen of the major ORFs have similarity to genes in the databases, including bacterial glycerophosphoryl diester phosphodiesterase, bacteriophage T4 endonuclease V, D-isomer specific 2-hydroxyacid dehydrogenases, and beta-alanine synthetase and bacterial nitrilases. Two major ORFs resemble the virus major capsid protein. Three major ORFs contain three or more ankyrin-like repeat elements and four ORFs encode proline-rich proteins.

Amino Acid Sequence↗
PubMed1994

Two novel multigene families, 530 and 300, in the terminal variable regions of African swine fever virus genome.

Here, we describe two novel multigene families (MGF) present in the terminal variable regions of the African swine fever virus (ASFV) genome. MGF530 includes at least six related ORFs (averaging 530 amino acids) containing four well-conserved domains and amino acid identities ranging from 24 to 55%. MGF300 is composed of three ORFs (averaging 300 amino acids) containing three highly conserved domains and amino acid identities ranging from 25 to 46%. Amino terminal regions of predicted MGF530 and 300 proteins share significant similarity with each other and with the comparable regions of previously characterized MGF360 ORFs. Members of both MGF530 and 300 are transcribed in ASFV-infected porcine macrophages. These results indicate that the composition and organization of MGF in the terminal variable region of the ASFV genome are more complex than previously recognized.

African Swine Fever Virus↗
PubMed1994

Clinical judgment survey of mental-health professionals: I. An assessment of opinions, ratings, and knowledge.

A sample of mental health professionals listed in the National Register of Health Service Providers in Psychology was surveyed to examine attitudes with regard to the generalizability of findings from clinical judgment research, general beliefs and practices about clinical judgment, and knowledge of scholarly articles and books in the clinical judgment literature. Of the participants, 98.1% were doctoral-level psychologists engaged in clinical practice. Results suggested that participants consistently agreed that tasks used in studies of clinical judgment were not representative of the types of activities performed in their clinical practice. Respondents believed that the study of clinical judgment was important and that research could have meaningful implications for their clinical practice. Participants' knowledge of the judgment literature was significantly lower than expected.

Adult↗
PubMed1994

Passively transferred African swine fever virus antibodies protect swine against lethal infection.

The role of anti-viral antibodies in homologous protective immunity to a virulent African swine fever virus (ASFV) strain E75 was examined by passive transfer experiments in swine. Eighty-five percent of animals (n = 14) that received anti-ASFV immunoglobulin (Ig) survived challenge infection, while 100% mortality was observed in control group animals (n = 28) that received anti-pseudorabies virus Ig, normal swine Ig, or phosphate-buffered saline. With the exception of a significantly delayed and transient fever response, anti-ASFV Ig group animals remained clinically normal following challenge, whereas control group animals presented with clinical ASF on Day 4 postchallenge. Additionally a significant 3 day delay in onset of viremia and a 10,000-fold reduction in both mean and maximum virus titers were observed for animals given anti-ASFV Ig. These results indicate that anti-ASFV Ig alone will protect swine from lethal infection with virulent ASFV. Further, they support the view that the antibody-mediated protective effect is an early event that effectively delays disease onset.

African Swine Fever↗
PubMed1994

An African swine fever virus gene with similarity to the T-lymphocyte surface antigen CD2 mediates hemadsorption.

An open reading frame, LMW8-DR, in the African swine fever virus (ASFV) genome possesses striking similarity to the lymphocyte membrane antigen CD2. All characterized CD2 domains, including the amino-terminal signal sequence, IgV, hinge, IgC2, stalk, transmembrane, and proline-rich carboxy cytoplasmic domains, are highly conserved in the ASFV gene. Critical residues for the binding of the lymphocyte function-associated antigen (LFA-3) and CD59 and for T-cell activation are also partially conserved. LMW8-DR is actively transcribed in ASFV-infected swine macrophages and Vero cells at late times in the infection cycle and Vero and COS cells transiently expressing the LMW8-DR open reading frame hemadsorbed swine red blood cells. The structural and functional similarities of LMW8-DR to CD2, a protein that is involved in cell-cell adhesion and immune response modulation, suggest a possible role in the pathogenesis of ASFV infection.

African Swine Fever Virus↗
PubMed1994

African swine fever virus structural protein p72 contains a conformational neutralizing epitope.

We have previously described a monoclonal antibody (mAb 135D4) to an unidentified 70- to 72-kDa African swine fever virus (ASFV) protein that exhibited high levels of neutralizing activity against various virulent ASFV isolates. Here, we identify the reactive ASFV protein as the major virus structural protein p72. In vitro-translated products of the p72 protein gene were specifically immunoprecipitated by mAb 135D4. Immunoprecipitation of a nested set of truncated p72 in vitro translation products defined the region between amino acid residues 400 and 404 as necessary for mAb 135D4 reactivity. Five partially overlapping peptides (15mers) covering residues 388-446 failed to react with mAb 135D4, suggesting the conformational dependence of the epitope. Supporting this interpretation, larger in vitro translation products representing residues 56-282, 159-361, 360-508, and 507-646 also failed to react with mAb 135D4. Consistent with its involvement in virus neutralization, immunoelectromicroscopy, using a rabbit antiserum against mAb 135D4-purified p72, located the protein on the surface of unenveloped virus particles.

African Swine Fever Virus↗
PubMed1994

Long-term persistent infection of swine monocytes/macrophages with African swine fever virus.

Long-term persistent infection was established in 100% of pigs (n = 19) experimentally infected with African swine fever virus (ASFV). Viral DNA was detected in peripheral blood mononuclear leukocytes (PBML) at greater than 500 days postinfection by a PCR assay. Infectious virus was not, however, isolated from the same PBML samples. In cell fractionation studies of PBML, monocytes/macrophages were found to harbor viral DNA during the persistent phase of infection. This result indicates that monocytes/macrophages are persistently infected with ASFV and that ASFV-swine monocyte/macrophage interactions can result in either lytic or persistent infection.

African Swine Fever↗
PubMed1993

Virulent African swine fever virus isolates are neutralized by swine immune serum and by monoclonal antibodies recognizing a 72-kDa viral protein.

Convalescent swine serum to African swine fever virus (ASFV) isolate E75 neutralized the infectivity of virulent ASFV isolates E75, E70, Lisbon 60, Malawi Lil 20/1 and a low passage tissue culture adapted variant of E75, E75CV/V3, by 86-97% in Vero and macrophage cell cultures. A monoclonal antibody, mAb-135D4, recognizing an ASFV protein of 72 kDa also exhibited strong neutralizing activity with these viruses. Unexpectedly, both E75 immune sera and mAb-135D4 failed to neutralize high passage tissue culture adapted ASFV variants including Lisbon 60, Haiti, Dominican Republic I, Dominican Republic II, and Brazil II, even though mAb-135D4 reacted with all viruses. These results suggest that tissue culture adaptation of ASFV isolates may be associated with loss of specific determinants associated with virus neutralization. To our knowledge, this is the first report of an ASFV neutralizing epitope.

Adaptation, Biological↗
PubMed1992

Characterization of p30, a highly antigenic membrane and secreted protein of African swine fever virus.

We have identified and characterized a 30-kDa phosphoprotein (p30) of African Swine Fever Virus (ASFV) that is synthesized, membrane localized, and released into the culture medium at early times after infection. Sequence analysis of the p30 open reading frame predicts a highly antigenic protein with putative phosphorylation, glycosylation, and membrane attachment sites.

African Swine Fever Virus↗
PubMed1992

A murine model of pseudorabies virus latency.

The mouse is a useful laboratory animal for studying various aspects of pseudorabies virus (PRV) virulence. Mice are highly susceptible hosts for PRV infection and are unable to survive acute viral infection. Because of this, mouse models have not been useful for studying PRV latent infections. Here, we report an efficient strategy for establishing latent PRV infections in laboratory mice. Passive transfer of high titered neutralizing antibodies to mice prior to inoculation with highly lethal doses of PRV (Bartha) resulted in survival rates of at least 60% with establishment of latent infections in survivors. Latent PRV infection in mice was demonstrated by: (1) recovery of infectious PRV-Bartha from explants of trigeminal ganglion (TG), and (2) detection of PRV nucleic acids in latently infected TGs by in situ hybridization and polymerase chain reaction (PCR), between 2-8 months post-infection. This PRV latency model indicates that attenuated PRV strains, those currently used extensively in vaccination programs worldwide, can establish a reactivatable latent infection in an experimental host. The mouse model may be particularly useful for examining the molecular bases of PRV latency and reactivation.

Animals↗
PubMed1992

An empirical evaluation of three components of the tetrahedron model of clinical judgment.

The tetrahedron model of clinical judgment (Rock, Bransford, Maisto, and Morey, Clin. Psychol. Rev. 7:645-661, 1987; Rock, Bransford, Morey, and Maisto, Clin. Psychol. Rev. 8:411-416, 1988) provides a framework for identifying factors that may influence the judgments of psychotherapists (e.g., clinical and counseling psychologists, psychiatrists, social workers, etc). Three parameters of the model were experimentally manipulated: mode of of presentation of clinical information, patient, and judgment task. Sixteen clinical psychology graduate student therapists evaluated two patients on axis I and axis II of the DSM-III. Judgmental accuracy was influenced by main effects and two- and three-way disordinal interactions among the three model parameters. Additionally, we found that judgemental accuracy was positively related to experience and training. This relationship was evident only when experience was assessed with specific rather than general measures, and when the clinical materials were presented in an audiovideo format and hence resembled the conditions under which the clinicians in the study acquired that training and experience. Implications for the design of training programs that facilitate competency in clinical judgment are discussed.

Adult↗
PubMed1992

Identification of an African swine fever virus gene with similarity to a myeloid differentiation primary response gene and a neurovirulence-associated gene of herpes simplex virus.

Here we describe an open reading frame (LMW23-NL) in the African swine fever virus genome that possesses striking similarity to a murine myeloid differentiation primary response gene (MyD116) and the neurovirulence-associated gene (ICP34.5) of herpes simplex virus. In all three proteins, a centrally located acidic region precedes a highly conserved, hydrophilic 56-amino-acid domain located at the carboxy terminus. LMW23-NL predicts a highly basic protein of 184 amino acids with an estimated molecular mass of 21.3 kDa. The similarity of LMW23-NL to genes involved in myeloid cell differentiation and viral host range suggests a role for it in African swine fever virus host range.

African Swine Fever Virus↗
PubMed1990

Detection of latent pseudorabies virus in swine using in situ hybridization.

We have examined methods for detection of pseudorabies virus (PRV) latency in three groups of swine; naturally infected animals obtained from a field case; animals which have been experimentally infected with Becker or Iowa strains of PRV; and single reactors (single seropositive animals within PRV-free herds). In situ hybridization was shown to be more sensitive than explanation/co-cultivation for the detection of latent virus. Nervous tissues, in particular the trigeminal ganglia, were found to be the most reliable source for detecting latent PRV. The presence of latent PRV was not detected in lymphoid tissues examined.

Animals↗
PubMed1988

Empirically derived Symptom Checklist 90 subgroups of chronic pain patients: a cluster analysis.

Four hundred fifty-three chronic pain patients completed a Symptom Checklist 90 (SCL-90) and a comprehensive pain evaluation questionnaire. All patients were evaluated by a physician and rated on degree of pain pathology and pain behavior. The SCL-90 data were analyzed using two clustering procedures and replicated over two similar samples. Three distinct profiles emerged and represented high, medium, and low scores on the SCL-90. No differences were found between subgroups on demographic characteristics, compensation status, pain duration, or pain ratings. Patients in the high-profile subgroup showed the most emotional distress, reported that their pain interfered the most with all activities, and were most often judged to have high pain behavior. Little evidence was found to support a "denial" profile, as previously predicted. Further support was found for using the SCL-90 in assessing chronic pain patients.

Activities of Daily Living↗
PubMed1987

The derivation and validation of six Multidimensional Health Locus of Control Scale clusters.

The purpose of this research was twofold. First, to determine if eight Multidimensional Health Locus of Control types hypothesized by Wallston and Wallston (1982) existed. Second, to assess the reliability, validity, and clinical utility of the control types. Two investigations were conducted based on research procedures designed for the discovery of clusters. The first study involved the derivation and replication of MHLC clusters with a sample of 400 healthy undergraduate men and women. The results of Study 1 suggested the existence of six MHLC clusters: pure internal; double external; pure chance; yea sayer; nay sayer, and believer in control. The sample for Study 2 consisted of 90 female undergraduate and graduate students. The six-cluster solution was replicated in this second cross-validation study. Furthermore, construct validity of the clusters was established through computer simulation. Finally, relationships between clusters and the Krantz Health Opinion Survey suggested the clusters have a theoretical as well as a empirical foundation. The implications of these findings for clinical practice, for the development of the health locus of control construct, and for future research on the MHLC Scale are discussed.

Adolescent↗