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Biomedical subjects

T Patterson

Publications and source records attributed to T Patterson.

At least 55 records · Page 3Linked to original sources
PubMed1990

Reduction of immune function in life stress and depression.

Reduced cell-mediated immune function has been found in depressed patients and in distressed persons undergoing threatening life events. The present study examines the interaction between severe life stress and major depression to produce immune alterations in 36 matched pairs of hospitalized depressed patients and nondepressed controls. Both major depressive disorder and the presence of threatening life events in control subjects are independently associated with a 50% reduction of natural killer (NK) cytotoxicity. A decrease in natural cytotoxicity is significantly associated with depressive symptoms but not with age, alcohol consumption, or tobacco smoking. These findings of altered immunity provide further evidence that the physiological responses in chronic stress parallel those found in the syndrome of depression.

Adult↗
PubMed1989

Cloning and expression of a collagen-analog-encoding synthetic gene in Escherichia coli.

A family of totally synthetic genes coding for multiple tandem repeats of the amino acid sequence (Gly-Pro-Pro) has been prepared and inserted into the ClaI cloning site of the expression vector pJL6. A representative recombinant plasmid, pAC1, with an insert of about 340 bp was established in an Escherichia coli strain bearing a defective lambda prophage, to study expression of the CII-collagen analog fusion protein produced from pAC1 upon heat induction. Authentic fusion protein production was demonstrated by nucleotide sequencing, Northern-blot analysis, and in vivo synthesis. Conversion of a wild-type rpoH allele to the rpoH165 mutation was shown to suppress proteolysis of the unstable fusion protein.

Amino Acid Sequence↗
PubMed1989

Survey of attitudes to testing for human immunodeficiency virus infection in antenatal clinics in West Glamorgan.

A total of 1023 women attending hospital antenatal clinics in West Glamorgan was surveyed by means of a self-administered questionnaire, to determine their attitudes to HIV testing in pregnancy. The response rate was 98%. Of the responders, 94% had no objection to their antenatal blood specimen being tested for HIV infection. Of the non-objectors, 55% wished their permission to be asked first, and 92% wished to be informed of the result, i.e. they wished for named testing. With regard to knowledge of other tests for infectious diseases performed on antenatal blood specimens, only 1.5% had totally correct knowledge, and only one in three knew that their blood was tested for syphilis. The implications of anonymous and named HIV testing are discussed, together with estimates of prevalence of HIV infection in women attending antenatal clinics, the rate of vertical transmission, and the prognosis for an infected baby.

AIDS Serodiagnosis↗
PubMed1989

Outpatient methadone programme for pregnant heroin using women.

A prospective study of pregnant narcotic users who attended the antenatal clinic at Westmead Hospital was undertaken to determine the practicality and safety of an outpatient methadone programme for these women. Forty-six women were commenced and managed on a methadone maintenance programme based at the Drug and Alcohol Clinic at Westmead Hospital (GROUP I), 12 women were maintained on long-term methadone therapy by outside prescribers (GROUP II), 12 women not on methadone continued to use heroin through the pregnancy (GROUP III), 14 women used heroin intermittently (GROUP IV). These were compared with a group of 52 women who were non-drug using (GROUP V). Women on the hospital based methadone programme had an earlier first antenatal clinic visit (p less than 0.001) than those women on outside methadone programmes or on heroin and had a longer pregnancy (p less than 0.001) than those women on heroin. The birth-weights on babies delivered to women on the Westmead Methadone Programme were significantly higher than those on babies born to women using heroin (p less than 0.05). A disappointing aspect of the study was a lower number of antenatal clinic visits (p less than 0.001) for all narcotic using women when compared with the comparison group. The outcome of the Westmead Methadone Programme women showed that better maternal and neonatal outcome followed entry into a hospital monitored methadone programme with attendant antenatal care.

Adult↗
PubMed1989

Severely threatening events and marked life difficulties preceding onset or exacerbation of multiple sclerosis.

Information was obtained on stressful life circumstances, using the Life Events and Difficulties Schedule (LEDS) from 39 patients with early multiple sclerosis and 40 matched nonpatient volunteers. The proportion of multiple sclerosis patients who experienced marked life adversity in the year prior to onset of symptoms was significantly higher than for nonpatients in the year before interview (77% vs. 35%). The excess in marked life stress was most evident in the 6 months before onset. Such stressors might explain the timing of symptom exacerbation for some patients with multiple sclerosis, perhaps by perturbing an already unstable neuroimmunological system.

Adaptation, Psychological↗
PubMed1989

Mortality rates of patients admitted to a psychogeriatric assessment unit.

Admission of elderly people to a geriatric hospital may carry an increased risk of death. In this study 355 admissions of 243 elderly persons with dementia to a purpose built psychogeriatric unit were studied and the mortality rate found to be 8.2%, which is less than that reported elsewhere. Admission for the purpose of respite (holiday) relief is a safe procedure and should not be discouraged.

Aged↗
PubMed1988

Indwelling umbilical arterial catheter: a preferred sampling site for blood culture.

Indwelling umbilical arterial catheter was evaluated prospectively as an alternative site for blood culture sampling. In 282 infants, 318 paired blood cultures were obtained from the peripheral vein and from the indwelling umbilical arterial line. Duration of umbilical catheter placement ranged from 0.5 to 196 hours; in 17% of the infants, catheters were in place for between 24 and 196 hours. In 13 blood culture pairs the same pathogens were found and had been obtained from the peripheral vein and the umbilical arterial line. Two pairs were positive for discrepant organisms. A total of 11 pairs were positive in one site only, with five positive from peripheral vein only and the other six from the umbilical arterial catheter. However, most of these single-site positive blood cultures were apparently true positives based on supporting laboratory data for infection. Contamination rates were 1.3% and 0.9% for peripheral vein and umbilical arterial catheter blood cultures, respectively. Thus, in sick neonates, the indwelling umbilical arterial line was an alternative and perhaps a preferred site for blood culture sampling.

Blood↗
PubMed1987

Life events do not predict symptoms: symptoms predict symptoms.

The effects of life events and previous symptoms on current symptom levels were examined in a model using data from a 3-year prospective study. Male psychiatric patients and nonpatients reported on life events and symptoms every 2 months on 18 occasions. Logistic regression analysis of these data revealed little dependence of psychiatric symptoms on preceding life events as measured by the Holmes and Rahe Schedule of Recent Experiences (SRE). The best predictor of the current symptom level was the level of previous symptoms. It is concluded that efforts to relate changes in the social environment to health must first consider the possible contribution of the antecedent symptom level to the variability in health outcome.

Adult↗
PubMed1987

Assessing knowledge of cardiovascular health-related diet and exercise behaviors in Anglo- and Mexican-Americans.

This article describes the Adult and Child Behavior Knowledge Scales that were used as part of the San Diego Family Health Project to measure knowledge of health behaviors related to cardiovascular diseases in two ethnic groups: Anglo- and Mexican-Americans. The psychometric characteristics of these scales indicate acceptable reliabilities for assessing knowledge of dietary sodium, dietary fat, and exercise among both adults and children and differ from other health knowledge scales in that they focus on "behavioral capability" rather than on the link between behavior and disease. It is believed that the type of information measured by our scales is more closely related to behavior changes sought in contemporary cardiovascular disease prevention trials. Results of ANOVA used to test differences in knowledge by ethnicity and sex indicate strong main effects for ethnicity among both children and adults. However, sex was not consistently related to knowledge, except for the general tendency of males to be more knowledgeable about exercise. Step-wise and simultaneous-entry multiple regression were used to test a subset of variables, including sex, education, self-efficacy, acculturation (for Mexican-Americans), and parental health knowledge (for children) as determinants of health knowledge. Education was the strongest predictor for Anglo-American adults, and acculturation level was the strongest for Mexican-American adults. Among children, the only statistically significant variable was parental acculturation level for Mexican-Americans. The scales were found to be useful in measuring differences in knowledge across cultural/linguistic groups and to clearly identify marginally acculturated Mexican-Americans as being least aware of health-behavior knowledge. Implications are discussed.

Acculturation↗
PubMed1987

Topographic evoked potentials during backward masking in schizophrenics, patient controls and normal controls.

1. A backward masking task with simultaneous measurement of topographically mapped evoked potentials was performed by normal, schizophrenic, and patient control subjects. 2. Behavioral results replicated previous studies demonstrating schizophrenic deficit and to a lesser extent patient control deficit in this task. 3. Two competing theories of (A) defects in "gating" mechanisms or (B) failure in early stimulus "registration" processes were tested. 4. Topographical evoked response maps indicated a significant absence of a negative going wave in the 70-100 msec epoch in the schizophrenic group relative to both control groups. 5. As the 70-100 msec negativitity attenuation occurred during target presentation, and well before mask onset, it was concluded that schizophrenic deficit in this task consists of a failure in initial stimulus "registration" processes within the time allowed for stimulus availability. 6. Such defective mechanisms may be significant in the pathogenesis of schizophrenia.

Adolescent↗
PubMed1987

Studies toward the subcortical pathogenesis of schizophrenia.

In addition to introducing the six articles joined by our thematic outlook, this article addresses the importance of subcortical structures as they may be related to information processing and the life experience of schizophrenic patients. This is a heuristic exercise aimed at bridging the conceptual gaps between clinical and research approaches to schizophrenia. A brief overview is then provided of current conceptualizations of a number of subcortical structures, each of which may play a part in the subcortical pathogenesis of schizophrenia in specific patients. The central concepts are failures in the "automaticity" with which prior experience may be recreated in parallel with current stimulus input in schizophrenia (with concomitant failures in future orientation or contextually generated expectancy), and the view of subcortical structures as constituting a "system" in which no single type of defect may be common to all schizophrenic patients.

Brain↗
PubMed1986

Thought disorder in schizophrenia: cognitive and neuroscience approaches.

Research with schizophrenics is reviewed in the areas of the startle reflex, subject-initiated evoked potentials, and two-stimulus evoked potentials. A hypothesis of an early (pre-100 ms) information-processing deficit is posited and further refined by results presented from brain evoked potentials during a backward-masking experiment. The implications of these findings for the speech component of schizophrenic thought disorder are speculated upon, with specific reference to failures of temporal sequencing control that may underlie schizophrenic speech dysfunction and may be attributable to defective thalamic control. Recent neuroanatomical findings of abnormalities in the hippocampus and thalamus of schizophrenics are presented, and considered as likely contributors to the early information-processing deficits posited.

Adolescent↗
PubMed1986

San Diego family health project: reaching families through the schools.

This project tests the effectiveness of a family-based health behavior change intervention in two ethnic groups. The aim is to help family members initiate and maintain dietary and physical activity behaviors believed to be linked to risk factors for cardiovascular disease. This paper describes the project and the baseline results. Twelve San Diego elementary schools were randomly assigned to intervention or control conditions. Hispanic and Anglo families with a fifth or sixth grade child were recruited to participate in a two-year study. The intervention emphasizes enjoyable experiences designed to transmit knowledge and skills required for long-term changes in diet and physical activity habits. Groups of families met at schools for 12 weekly sessions and six maintenance sessions distributed throughout the following nine months. Outcome behavioral and physiologic measures will be collected at baseline, three months, 12 months, and 24 months. Differences between Anglo and Mexican-American subjects justify targeted activities specific to these groups.

Adult↗
PubMed1985

Electron microscopic visualization of trp operon expression in Salmonella typhimurium.

Transcriptional activity of plasmids carrying wild-type and mutant trp operons was visualized in cell lysates of Salmonella typhimurium. Plasmid and transcription-unit sizes varied with the size of the cloned operon. Following 3-(3-indolyl)acrylic acid derepression, all operons of a particular type exhibited the same high level of transcriptional activity. An estimated 11-14 transcripts must be initiated each minute to maintain the 190-base-pair spacing of RNA polymerases observed on the promoter-proximal half of the wild-type trp operon. A decline in RNA polymerase density was observed on promoter-distal portions of cloned trp operons, which may be attributable to premature transcription termination accompanying translation inhibition due to indolylacrylic acid's interference with normal tryptophanyl-tRNA synthetase activity.

Chromosome Deletion↗
PubMed1984

A specialized host-vector system for the in vivo cloning of the trp operon of wild-type and mutant strains of Salmonella typhimurium by generalized transduction.

Using in vitro methods, a 14.2-kb EcoRI fragment of the Salmonella typhimurium chromosome containing the trp operon plus associated flanking sequences from deletion mutant delta trpDCB763 was cloned into the EcoRI site of plasmid pBR322 in a S. typhimurium host. An in vivo cloning vector was constructed from the recombinant plasmid by the in vitro excision of a SalI fragment that contains the entire trp operon. The derived plasmid (pSTP21) carries a hybrid insert made up of the 5.4-kb EcoRI-SalI upstream flanking sequence and the 3.2-kb SalI-EcoRI downstream flanking sequence. Plasmid pSTP21 has been used as a receptor plasmid to clone a variety of mutant and wild-type trp operons by RecA-dependent in vivo recombination between the insert DNA of the plasmid and the homologous trp flanking sequences of transducing DNA fragments transferred into the cell by bacteriophage P22. The host-vector system developed for the in vivo cloning permits the differentiation of plasmid transductants from chromosomal transductants on the primary selective medium. Expression of the cloned trp operons is regulated normally by tryptophan. A substantial amplification of trp enzymes is attainable upon derepression. The recombinant plasmids are stably inherited in RecA+ and RecA- S. typhimurium hosts. However, conditions of high expression of the trp operon lead to a rapid loss of cellular viability and of plasmid stability.

Cloning, Molecular↗