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C J Gibbs

Publications and source records attributed to C J Gibbs.

At least 19 recordsLinked to original sources
PubMed1992

Recommendations of the International Roundtable Workshop on Bovine Spongiform Encephalopathy.

Recommendations of the working party were summarized as follows: Determine the status in all countries of their national cattle herds with respect to BSE. Attempt to develop a test to recognize BSE-infected animals before they become clinically ill. Establish procedures to prevent spread of BSE agent into the cattle populations, especially by eliminating feeds containing rendered ruminant proteins. Review the rendering processes, identify the sources and destinations of rendered products, and suggest appropriate changes if needed. Especially needed are standardized rendering procedures in regard to use of organic solvents, temperature, and duration of heat treatment. Review import and export regulations to reduce the risk of spreading BSE and to maximize opportunities for safe trading in cattle and cattle products. The scrapie-free certification program of the USDA was supported, and similar programs might be considered by other countries. If BSE/scrapie is diagnosed in a given country, determine baseline incidence of CJD in those countries and consider contributing to an international registry. The WHO should address the problems of BSE, formulate policy, participate in and coordinate research, and provide training opportunities for veterinary and human health care workers from eastern European countries and developing nations. Government and private agencies should consider increasing support for research on transmissibility and pathogenesis of CJD, BSE, CWD, scrapie, and transmissible mink encephalopathy. Prepare and publish a critical neuropathologic review of all spongiform encephalopathies, naturally and experimentally transmitted, defining the characteristics of each disease in the various species known to be susceptible. Consider producing guidelines for the biological and pharmaceutical industries with regard to sourcing, collecting, and processing bovine and ovine materials.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

Phenotypic characteristics of familial Creutzfeldt-Jakob disease associated with the codon 178Asn PRNP mutation.

A group of 43 patients from seven families affected by Creutzfeldt-Jakob disease (CJD) with the codon 178Asn mutation of the PRNP amyloid precursor gene is compared to a group of 211 patients with the sporadic form of the disease. As a group, the patients with the codon 178Asn mutation had an earlier age at onset of illness (almost always presenting as an insidious loss of memory), a longer duration of illness, and an absence of periodic electroencephalographic activity. Transmission of disease to primates was accomplished using brain tissue homogenates from 6 of 10 patients, resulting in significantly shorter incubation periods than those due to sporadic CJD inocula. These findings are interpreted and discussed in terms of possible differences in the temporospatial evolution of damage to the brain, and of accelerated induction of polymerized amyloid protein by its mutationally altered template precursor.

Age Factors↗
PubMed1992

Absence of measles, mumps, and rubella viral genomic sequences from multiple sclerosis brain tissue by polymerase chain reaction.

We tested for measles, mumps, and rubella viruses in multiple sclerosis by polymerase chain reaction (PCR). Using RNA extracted from 19 multiple sclerosis and 8 control brain specimens, nested PCR was performed after reverse transcription (RT) of the RNA to cDNA using primer pairs directed against two regions in the genomes of measles and mumps viruses and one region in the rubella virus genome. Despite enhanced sensitivity of nested RT PCR, measles, mumps, and rubella viral genomic sequences were not found in any brain specimen.

Adult↗
PubMed1992

Lack of JC viral genomic sequences in multiple sclerosis brain tissue by polymerase chain reaction.

With DNA extracted from brain specimens from 19 multiple sclerosis, 5 progressive multifocal leukoencephalopathy, 1 Alzheimer's disease, and 8 nonneurological control subjects, polymerase chain reaction was performed using nested sets of primer pairs amplifying segments of the large T and VP1 antigen-encoding sequences of JC virus. Both sequences were detected in each of the 5 brain specimens of progressive multifocal leukoencephalopathy but in none of the 19 multiple sclerosis, 1 Alzheimer's disease, or the 8 control brain specimens.

Base Sequence↗
PubMed1992

Neuronal autophagic vacuoles in experimental scrapie and Creutzfeldt-Jakob disease.

We report the presence of autophagic vacuoles (AV) in neuronal perikarya and neuronal processes of rodents with experimental scrapie and Creutzfeldt-Jakob disease. AV were composed of sequestrated cytoplasmic areas containing ribosomes and occasionally mitochondria and small secondary vacuoles. The formation of AV may contribute to neuronal degeneration and ultimately to neuronal loss.

Animals↗
PubMed1992

Purification of non-infectious ganglioside preparations from scrapie-infected brain tissue.

The extraction and purification of gangliosides from brains of animals infected with the scrapie agent was evaluated by scaling-down a large-scale procedure currently used with bovine brains. Inactivation experiments employed hamster brains infected with the 263 K strain of scrapie. Residual infectivity was determined at different points of the procedure and in the final preparation by an in vivo animal bioassay. The efficacy of single steps, which included chemicals or physical techniques known to affect the viability of the scrapie agent, was verified by spiking experiments where known amounts of infectivity were added just before each single step. Infectivity was significantly diminished at early stages of the purification, and no infectivity was detected in the final preparation containing purified gangliosides. The significant reduction of infectivity at intermediate steps and the total absence of detectable infectivity in the final product confirmed that a combination of heat and exposure to sodium hydroxide, even in the presence of organic solvents, completely inactivated the scrapie agent.

Animals↗
PubMed1992

Comparative ultrastructural neuropathology of naturally occurring bovine spongiform encephalopathy and experimentally induced scrapie and Creutzfeldt-Jakob disease.

We report the ultrastructural neuropathology of bovine spongiform encephalopathy (BSE), a recently described slow virus disease first recognized in Friesian/Holstein cattle, and compare it to that of experimental scrapie and Creutzfeldt-Jakob disease. The spongiform change, which was most pronounced in the central grey matter of the midbrain, consisted of membrane-bound vacuoles within neuronal processes, containing curled membrane fragments, secondary chambers and vesicles. Axons and dendrites accumulated whorls of neurofilaments and other subcellular organelles, such as mitochondria and dense bodies, which were entrapped within the filamentous masses. Other neurites accumulated electron-dense bodies, and still others electron-lucent cisterns and branching tubules. Membrane-bound neuronal inclusions, composed of tubules measuring 10 nm in diameter, were found in axonal terminals. Tubulovesicular structures were loosely packed and were occasionally surrounded by a common membrane, a finding previously described only in natural scrapie in sheep. Except for the intraneuronal inclusions, all of the ultrastructural features of BSE resembled those found in scrapie and Creutzfeldt-Jakob disease.

Animals↗
PubMed1992

Ultrastructural pathology of axons and myelin in experimental scrapie in hamsters and bovine spongiform encephalopathy in cattle and a comparison with the panencephalopathic type of Creutzfeldt-Jakob disease.

We report the ultrastructural pathology of axons and myelin sheaths in bovine spongiform encephalopathy (BSE) and experimental scrapie in hamsters and compare it with that found in a panencephalopathic model of Creutzfeldt-Jakob disease (CJD). Intramyelinic vacuoles (myelin ballooning), dystrophic axons, phagocytic astrocytes and macrophages were found in all three models but to different degrees, while axons containing numerous cellular processes and concentric cisterns were observed only in experimental scrapie and CJD. We conclude that axonal and myelin pathology is a widespread phenomenon and the differences between panencephalopathic CJD and polioencephalopathic BSE and scrapie are only quantitative.

Animals↗
PubMed1992

An insert mutation in the chromosome 20 amyloid precursor gene in a Gerstmann-Sträussler-Scheinker family.

We report the finding of an insert mutation in the chromosome 20 amyloid precursor gene in a family with neuropathologically-verified, experimentally-transmitted Gerstmann-Sträussler-Scheinker syndrome (GSS). The insert consisted of 8 extra copies of a repeating octapeptide coding sequence in the region between codons 51 and 91; it was identified in the proband and a presently unaffected at-risk niece by full sequencing of the open reading frame, and was visualized electrophoretically in the proband and 6 of 12 at-risk relatives. Although affected members in this French-Breton family have shown a variety of clinical profiles, including durations of illness that ranged from 3 months to 13 years, all autopsied cases (including the patient with the shortest illness) have had the distinctive multicentric amyloid plaques that define GSS as a nosologic entity.

Adult↗
PubMed1992

Familial Creutzfeldt-Jakob disease in Chile is associated with the codon 200 mutation of the PRNP amyloid precursor gene on chromosome 20.

We have found the codon 200Lys mutation in 6 Chilean CJD families, including a family in the rural case cluster in Chillán. Thus, all 3 of the known clusters of CJD, in Slovakia, Libyan-born Israeli Jews, and Chile, are linked to the presence of the same mutation. The phenotypic features of the disease in these families are similar to those reported for other clustered or individual families elsewhere in the world. The heterogeneous genetic composition of the Chilean population interpreted in light of historical migration patterns suggests that the mutation may have entered Chile by Jewish emigration from Spain.

Adult↗
PubMed1992

Seroprevalence and cofactors of HTLV-I infection in Tumaco, Colombia.

This study presents an analysis of the factors associated with HTLV-I seroprevalence in the endemic area of Tumaco, Colombia. During June to August 1988, 1,077 individuals were selected at random from a population of 45,594. The overall prevalence rate of HTLV-I antibodies was 2.8%. Among females prevalence was significantly higher (p less than 0.02) than among males. Rates increased substantially with age. HTLV-I prevalence among individuals with history of use of intravenous medications was significantly higher (p less than 0.001) than in those without such history. Logistic regression analysis included age in years, indicators for male gender, and for i.v. injections, and their interactions. Age was very strongly associated to HTLV-I infection among females. At early ages prevalence was not different between sexes, but females presented a significantly higher rate than males after age 42. History of i.v. administered medications was very strongly associated in the univariate analysis and, although significance was borderline in the multivariate analysis, it had the effect of doubling the odds of HTLV-I infection.

Adolescent↗
PubMed1992

Atypical Creutzfeldt-Jakob disease in an American family with an insert mutation in the PRNP amyloid precursor gene.

An American family of English origin with an unusually early onset and long-duration form of Creutzfeldt-Jakob disease (CJD) had a heterozygous insert mutation in the region of repeating octapeptide coding sequences between codons 51 and 91 of the PRNP gene on chromosome 20. Affected members were 23 to 35 years old at the onset of illnesses that lasted from 4 to 13 years, yet experimental transmission of disease from the proband (11-year duration) produced a typically brief incubation period and duration of illness in each of three inoculated primates. Also, the PrP amyloid protein that accumulates in CJD brain was only barely detectable in extracted brain tissue from one case with massive spongiform change and was undetectable in another case with no spongiform change, perhaps because of epitope shielding by a configurational change in the protein induced by the mutation. Analysis of this and other families with similar inserts suggests that such mutations in the PRNP gene not only predispose to CJD, but also modify its phenotypic expression.

Adult↗
PubMed1992

HTLV-I DNA sequences in CNS tissue of a patient with tropical spastic paraparesis and HTLV-I-associated myelopathy.

Human T cell lymphotrophic virus type I (HTLV-I) is the etiologic agent of adult T cell lymphoma/leukemia (ATLL) and tropical spastic paraparesis/HTLV-I-associated myelopathy (TSP/HAM). We studied an HTLV-I-seropositive, white man diagnosed in 1977 with ATLL and 10 years later, 6 months prior to his death, with TSP/HAM. Sections of brain, spinal cord, and visceral tissues were examined histologically, immunohistochemically, by in situ hybridization, and by the polymerase chain reaction (PCR). PCR amplification of a region of the polymerase (pol) gene of HTLV-I from visceral tissue demonstrated the presence of proviral HTLV-I DNA in paraffin-embedded sections from the liver and in DNA extracted from frozen sections of kidney and spleen, but failed to demonstrate viral sequences in paraffin sections of the lung and a lymph node. PCR analysis of CNS tissue demonstrated viral sequences in regions of the brain including frozen samples from cerebellum and cerebral cortex and paraffin sections of the thoracic spinal cord, but failed to detect proviral DNA in sections from a region in the lumbar cord. These results map the distribution of HTLV-I DNA sequences in the CNS of a patient with TSP/HAM for 3 months.

Blotting, Northern↗
PubMed1991

Transmissible familial Creutzfeldt-Jakob disease associated with five, seven, and eight extra octapeptide coding repeats in the PRNP gene.

The PRNP gene, encoding the amyloid precursor protein that is centrally involved in Creutzfeldt-Jakob disease (CJD), has an unstable region of five variant tandem octapeptide coding repeats between codons 51 and 91. We screened a total of 535 individuals for the presence of extra repeats in this region, including patients with sporadic and familial forms of spongiform encephalopathy, members of their families, other neurological and non-neurological patients, and normal controls. We identified three CJD families (in each of which the proband's disease was neuropathologically confirmed and experimentally transmitted to primates) that were heterozygous for alleles with 10, 12, or 13 repeats, some of which had "wobble" nucleotide substitutions. We also found one individual with 9 repeats and no nucleotide substitutions who had no evidence of neurological disease. These observations, together with data on published British patients with 11 and 14 repeats, strongly suggest that the occurrence of 10 or more octapeptide repeats in the encoded amyloid precursor protein predisposes to CJD.

Adult↗
PubMed1991

Observations after human immunodeficiency virus immunization and challenge of human immunodeficiency virus seropositive and seronegative chimpanzees.

Two human immunodeficiency virus (HIV)-seropositive chimpanzees (A-3 and A-86c) infected 4 yr earlier with HIV, along with one uninfected animal (A-36), were inoculated intramuscularly three times in a year with a gamma-irradiated gp120-depleted HIV immunogen in incomplete Freund's adjuvant. Both previously infected animals promptly developed an anamnestic humoral antibody response after the first dose, and the uninfected animal developed a primary humoral response to the first dose and then an anamnestic response to the second dose. Although HIV had been recovered repeatedly from the seropositive animals, they became persistently virus-culture negative at the time of or just before the first inoculation of the immunogen. Intravenous challenge with 40 chimpanzee-infectious-doses of a heterologous HIV strain (HIVIIIB) was done 4 mo after the third inoculation in the three treated chimpanzees and in an untreated control animal (A-189a). The immunized naive animal (A-36) and the unimmunized control (A-189a) became infected, and virus has been isolated from their peripheral blood mononuclear cells for greater than 2 yr after challenge. However, the two previously infected chimpanzees (A-3 and A-86c) resisted challenge and have remained virus negative by peripheral blood mononuclear cell cocultivation for greater than 2 yr of observation after challenge; moreover, no evidence of reinfection was detectable by PCR. Despite the in vivo resistance, however, peripheral blood mononuclear cells from the resistant animals (A-3, A-86c) remained susceptible to infection by HIV in vitro. These findings reveal that a state of immunity can develop and/or be induced to control and/or prevent HIV infection in the chimpanzees. In the absence of any detectable level of neutralizing antibody in A-3 and a low level in A-86c, the patterns of the responses to challenge seen in the four animals suggest that the cell-mediated immune mechanism must have played a significant role in the resistant chimpanzees both in control of their HIV infection and in their resistance to challenge.

Animals↗
PubMed1991

In situ hybridization detection of HTLV-I RNA in peripheral blood mononuclear cells of TSP/HAM patients and their spouses.

This is the first report of the direct detection of HTLV-I RNA in uncultured peripheral blood mononuclear cells (PBMNC's) of patients with tropical spastic paraparesis and HTLV-I-associated myelopathy (TSP/HAM) and their spouses, using the technique of in situ hybridization. Twenty-one Colombian patients were tested, all of whom had antibodies to HTLV-I; the presence of HTLV-I proviral DNA in their PBMNC's was confirmed by the polymerase chain reaction technique. Of the 21 patients 15 had a clinical diagnosis of tropical spastic paraparesis (TSP/HAM), 5 were asymptomatic relatives, and 1 patient had leukemia. In situ hybridization was positive in samples from 5 patients; 2 of these were TSP/HAM patients and the other 3 were healthy wives of TSP/HAM patients. This study demonstrates for the first time that viral RNA is expressed in uncultured PBMNC's of some patients with TSP/HAM in whom proviral DNA is also present; furthermore, the detection of HTLV-I RNA in the blood of female partners of TSP/HAM patients clearly illustrates the high likelihood of HTLV-I transmission through sexual contact.

Cell Line↗