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C O'Brien

Publications and source records attributed to C O'Brien.

At least 55 records · Page 3Linked to original sources
PubMed1989

Integrated R2 sequence in mitochondria of fertile B37N maize encodes and expresses a 130 kD polypeptide similar to that encoded by the S2 episome of S-type male sterile plants.

Expression of a 130 kDa protein from open reading frame 1 of the integrated form of the R2 mitochondrial plasmid in normal mitochondria of B37 and other inbred lines is described. The protein appears identical to that synthesized by the closely related S2 episome found in cytoplasmic male sterile maize of the S type. Protein was detected using antisera raised against a beta-galactosidase:ORF1 fusion product containing the most antigenic region of the ORF1 product. Detection of this protein is in contrast to previous reports that mitochondria of normal, male-fertile lines either do not contain this protein, or that there are 11 in-frame stop codons in the reading frame. The integrated R2 of B37N was cloned and this region sequenced, confirming that a continuous open reading frame existed. These results are discussed in relation to the possible role of the S-type episomes in causing cytoplasmic male sterility.

Amino Acid Sequence↗
PubMed1989

Differences in the chemical expression of rat primary afferent neurons which innervate skin, muscle or joint.

The fluorescent dye Fast Blue was injected in anaesthetized rats into either skin, muscle or knee joint of the hindlimb. Following retrograde transport of the dye to lumbar dorsal root ganglia, the cell bodies of primary afferent neurons innervating these different target tissues were identified in ganglion sections by fluorescence microscopy. The sections were processed to demonstrate activity of the enzyme thiamine monophosphatase, or immunoreactivity to calcitonin gene-related peptide, substance P, or somatostatin, in Fast Blue labelled neurons. In all cases immunoreactivity to the antineurofilament antibody RT97 was used to classify dorsal root ganglion cells as being either small dark (RT97 negative, unmyelinated axons) or large light (RT97 positive, myelinated axons). The proportion of small dark cells labelled from each target decreased in the order: skin, muscle, joint. Thiamine monophosphatase and somatostatin were present only in small dark cells, while calcitonin gene-related peptide and substance P were found in both small dark and large light cells. In large light cells of all three targets, more contained calcitonin gene-related peptide than substance P. Among small dark cells, thiamine monophosphatase and somatostatin were found predominantly in skin afferents, while calcitonin gene-related peptide and substance P were more common in muscle and joint afferents. The chemical expression of primary afferents is therefore characteristic of the peripheral target they innervate. This could reflect either a maintained influence of the target on the afferents, or the factors which operate only during development.

Animals↗
PubMed1989

Heterogeneity of the Ro/SSA antigen. Different molecular forms in lymphocytes and red blood cells.

Ro(SSA) is an intracellular ribonucleoprotein against which autoantibodies are found in a portion of patients with Sjögren's syndrome and systemic lupus erythematosus. A form of Ro(SSA) is described in red blood cells that shares a line of identity with purified Ro(SSA) from bovine spleen and human lymphocytes in counterimmunoelectrophoresis, but has different molecular properties. Ro(SSA) from red blood cells exists in association with only two small RNAs as opposed to four in other cell types, as determined by RNA extraction of protein A-assisted immunoprecipitates. In addition to the common 60-kD Ro(SSA) protein, Western blot analysis revealed an additional 52-kD protein in lymphocytes and a 54-kD protein in red blood cells. The 60-kD form of Ro(SSA) in red cells was found to be antigenically distinct from that in the lymphocyte, because sera were identified that bound each exclusively. Finally, a rabbit antibovine Ro(SSA) serum distinguished red cell from lymphocyte Ro(SSA). These results suggest two distinctive populations of Ro(SSA) proteins and distributions of Ro(SSA) RNAs in the lymphocyte and red blood cell.

Animals↗
PubMed1989

Anti-KJ: a new antibody associated with the syndrome of polymyositis and interstitial lung disease.

Antibodies to aminoacyl-tRNA synthetases (anti-Jo-1, anti-PL-7, anti-PL-12) have been found in the serum of some patients with polymyositis (PM). Patients with these antibodies have an unusually high rate of interstitial lung disease (ILD) in association with their PM. Two patients (K.J. and B.T.) with severe ILD and PM were found to have antibodies to a cytoplasmic antigen, but tests to determine whether the antigen was an aminoacyl-tRNA synthetase were negative, including tests of KJ serum for inhibitory effects on the 20 synthetases. KJ immunoprecipitates did not contain tRNA, in contrast to antisynthetase sera. When IgG samples were added to a reticulocyte in vitro translation system at a concentration of 0.3 mg/ml, KJ IgG inhibited globin mRNA translation by 98%, while anti-Jo-1 IgG inhibited 62% and normal IgG had little effect. Thus, both anti-KJ and the antisynthetases are directed at antigens that are involved in translation and protein synthesis, and both are associated with the syndrome of lung disease and PM. This syndrome may be associated with antibodies to translation-related proteins in general, which may have implications for the link of PM and enteroviruses, which are mRNA viruses.

Adult↗
PubMed1989

Up from under.

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Employment↗
PubMed1989

AIDS: time to change.

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Acquired Immunodeficiency Syndrome↗
PubMed1988

Non-Hodgkin's lymphoma: case control epidemiological study in Yorkshire.

This paper reports the results of a case control study of non-Hodgkin's lymphoma in the Yorkshire Health Region. In all, 437 cases and 724 controls were interviewed. Risk factors associated with past skin conditions, family history of cancer and infectious mononucleosis, aspects of social life and contact with wood dust and epoxy glues all emerge. A comparison of high and low grade morphological forms of disease reveal contrasting risks and suggest separate aetiologies for these conditions.

England↗
PubMed1988

Is inpatient medical alcohol detoxification justified: results of a randomized, controlled study.

The findings of this study revealed relatively few short-term outcome differences for patients meeting study criteria who were randomly assigned to either outpatient or inpatient medical detoxification. Given the higher costs of inpatient treatment, these findings suggest that outpatient detoxification be considered as a meaningful and cost-effective treatment for persons with mild to moderate alcohol withdrawal symptomatology.

Alcoholism↗
PubMed1988

Conditioned craving and arousal in cocaine addiction: a preliminary report.

Though data collection is still in progress, several significant findings are already apparent from our study of cocaine 'reminders': 1) In the laboratory, detoxified cocaine abusers show a differential responsivity to drug-related cocaine 'reminders', responding with strong signs of physiological arousal (peripheral skin temperature reductions and decreases in skin resistance) and subjective cocaine craving. 2) In extinction sessions, repeated, non-reinforced exposure to cocaine 'reminders' led to a complete reduction in craving to these stimuli by the fifteenth hour-long session. High and 'crash' responses were virtually eliminated by the sixth hour of extinction. 3) Physiological arousal to cocaine 'reminders' was often still in evidence even after fifteen hours of extinction. 4) Even after completing the current extinction protocol cocaine abusers may crave--and use--cocaine when experiencing drug 'reminders' in the natural environment. Clearly, detoxified cocaine abusers can experience conditioned craving and arousal to cocaine 'reminder' stimuli. These responses can be both intense and persistent, meaning that the abstinent cocaine abuser may be vulnerable long after detoxification is complete. Though the program of extinction described here is effective in reducing craving to cocaine-related stimuli presented in the context of the laboratory or clinic, this effect may not generalize well to the natural environment. We are currently considering two approaches to this problem: 1) One approach would attempt to increase the generalization of extinction by the use of even more realistic stimuli (e.g., the sight of real cocaine) and stimulus contexts (e.g., in vivo repeated exposures).(ABSTRACT TRUNCATED AT 250 WORDS)

Cocaine↗
PubMed1988

Update on behavioral treatments for substance abuse.

In the past five years there has been an encouraging increase in the amount and quality of research on behavioral treatments for substance abuse. Some of the most promising approaches combine behavioral treatments with each other (e.g., relapse prevention and cue exposure) or with other forms of treatment (e.g., psychotherapy), attempting to maximize impact on the multiple determinants of drug use. We are fast approaching the time when a patient may be systematically evaluated to develop a profile of vulnerabilities (cue responsivity, psychiatric symptoms, etc.) to rationally determine the treatment or combination of treatments of greatest potential benefit.

Behavior Therapy↗
PubMed1987

Chronic lymphocytic leukaemia: case control epidemiological study in Yorkshire.

This is the second report of a large case control study of lymphoma/leukaemia occurring in Yorkshire during 1979-84, and deals with chronic lymphocytic leukaemia presenting either in its haematological (CLL) or more solid lymphomatous (malignant lymphoma-lymphocytic or MLL) forms. In all, 330 cases and 561 controls were interviewed. The results support the concept that CLL/MLL is a condition of multiple aetiologies with evidence for genetic predisposition through an excess of family cases, immune perturbation demonstrated by excessive previous skin diseases and phenylbutazone use, and viral involvement shown by links with infectious diseases and multiple sclerosis.

Drug-Related Side Effects and Adverse Reactions↗