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T Patterson

Publications and source records attributed to T Patterson.

At least 37 records · Page 2Linked to original sources
PubMed1996

Spinal dural arteriovenous malformations. Intraoperative evoked potential evidence for pathophysiology. A case report.

STUDY DESIGN: This case report details intraoperative evoked potential changes during surgical removal of a T8 dural arteriovenous malformation. OBJECTIVES: The pattern of changes in somatosensory-evoked responses during surgical correction of spinal dural at arteriovenous malformation can illuminate the pathophysiologic process behind the clinical symptoms. SUMMARY OF BACKGROUND DATA: Arteriovenous malformation of the spinal dura can manifest with multiple symptoms, including progressive myelopathy and pain. The pathophysiologic process behind these symptoms could be either direct compression of the spinal cord by the arteriovenous malformation, ischemia resulting from the cord, or increased venous pressure. METHODS: To investigate these hypotheses further, the results of posterior tibial evoked potentials obtained during surgical removal of a T8 dural arteriovenous malformation were analyzed. RESULTS: At baseline, the cortical (P40) potential was markedly prolonged bilaterally. During surgery, just after the dura was opened, a marked increase was observed in the latencies of the P40 and P60 components of the evoked response on the right, which began to resolve as soon as the arteriovenous malformation was occluded. Only minimal changes were seen on the left. CONCLUSIONS: These results are most consistent with the increased venous pressure hypothesis for the pathogenesis of neurologic symptoms in dural arteriovenous malformations.

Aged↗
PubMed1996

Detection of stroke during cardiac operations with somatosensory evoked responses.

OBJECTIVES: The objectives of this study were to determine if monitoring of intraoperative somatosensory evoked potentials could be used to detect stroke during cardiac operations and to establish indicators of cerebral ischemia based on changes in these potentials. METHODS: Twenty-five patients undergoing cardiac operations underwent preoperative and postoperative neurologic examinations as well as intraoperative recording of somatosensory evoked potentials. Detailed analysis of the waveforms of these potentials was performed. RESULTS: Two of the 25 patients had intraoperative strokes. These patients and only these patients had changes in their somatosensory evoked potentials during the operation suggesting cerebral ischemia. The unilateral disappearance of the cortical somatosensory evoked potential waves correlated significantly with the clinical outcome of stroke (p < 0.004). Ischemic changes were detected in real time and were related to the removal of the aortic crossclamp in one patient and to the initiation of cardiopulmonary bypass in the other. CONCLUSIONS: Somatosensory evoked potentials can detect intraoperative stroke during cardiac operations. Acute, unilateral decreases in amplitude of the cortical potential are more useful than changes in latency in detecting intraoperative stroke.

Adult↗
PubMed1996

Microdilution antifungal susceptibility testing of Candida albicans and Cryptococcus neoformans with and without agitation: an eight-center collaborative study.

The growth patterns observed in the trailing wells when fluconazole is being tested may give rise to readings that suggest resistance or increased MICs for known susceptible strains. We conducted a multicenter study to evaluate the intralaboratory and interlaboratory reproducibilities of a method that uses agitation to disperse these types of growth. Ten strains of Candida albicans and five strains of Cryptococcus neoformans were tested against fluconazole, flucytosine, and amphotericin B by using a microdilution adaptation of the proposed reference method of the National Committee for Clinical Laboratory Standards for yeasts (M27-T). The endpoint criterion used before agitation was consistent with the M27-T recommendation, while a criterion of 50% or more reduction of growth compared with the control was used after agitation. The results of this study showed that use of agitation and the modified endpoint criterion both improved intralaboratory and inter-laboratory agreement and increased the frequency of interpretable MICs. The MICs obtained by this method were comparable to those obtained by the broth macrodilution M27-T method. Like M27-T, this method was not able to definitely distinguish amphotericin B-susceptible from -resistant strains, although the MICs for the resistant strains were consistently higher than those for the susceptible ones. The findings imply that agitation should be seriously considered when antifungal agents, particularly fluconazole, are tested in a microdilution format.

Amphotericin B↗
PubMed1996

Caught in the middle.

Explore the source record for details and available documents.

Administrative Personnel↗
PubMed1995

Psychiatric morbidity associated with acquired immune deficiency syndrome-related grief resolution.

This study examined acquired immune deficiency syndrome (AIDS)-related grief resolution and psychiatric morbidity in 286 human immunodeficiency virus (HIV)-positive and HIV-negative gay men examined between 1989 and 1993 in San Diego, CA. Psychiatric morbidity, mood ratings, and bereavement assessments were obtained using the Structured Clinical Interview for DSM-III-R, Hamilton Rating Scales for Depression and Anxiety, and Texas Revised Inventory of Grief. Sixty percent of the men (N = 171) reported a loss within the previous 12 months. Eighteen percent of the bereaved met criteria for unresolved grief. No differences were evident in lifetime psychiatric disorders, yet men with unresolved grief demonstrated an elevated prevalence of current major depression and panic disorder when compared with resolved grievers. Clinician sensitivity to the grief process and its relationship to psychiatric complications is an important component of comprehensive psychiatric and medical care of men at high risk for HIV during this era of AIDS.

Acquired Immunodeficiency Syndrome↗
PubMed1995

A collaborative approach to reduce hospitalization of developmentally disabled clients with mental illness.

Developmentally disabled clients with a concomitant mental illness are often underserved or inappropriately treated because of interorganizational barriers, leading to unnecessary hospitalization and lengthy delays in community placement. To overcome these barriers, agencies responsible for developmental disabilities and mental health services in Spokane County in Washington State developed a collaborative system of care in 1989. An interagency consortium was established to promote coordination of services between the community mental health center, the state hospital, the county human services agency, the state's regional developmental disability service agency, the state institution for the developmentally disabled, and several community agencies serving developmentally disabled persons. Between 1990 and 1992, admissions of developmentally disabled persons to the state hospital were more likely to be appropriate admissions of persons suffering from a mental illness, developmentally disabled clients were discharged more efficiently, and crisis respite services were used in place of hospitalization. In addition, anecdotal reports indicated a reduction of interagency tensions.

Community Mental Health Services↗
PubMed1995

An investigation into the default rate at the Fife colposcopy clinic: implications for target setting.

BACKGROUND: High default rates have been reported from the Fife colposcopy clinic in recent years. However, it was felt that this rate was misleading, as many patients who defaulted initially attended subsequent appointments. It was therefore decided to determine the default rate of a cohort of new patients given appointments at the clinic. The objective of the study was to determine the attendance rates for these new patients, between the dates they were first invited to their various appointments and the dates that their notes were subsequently examined as part of this study in September 1992. METHODS: A retrospective cohort study of new patients invited to the Fife colposcopy clinic was undertaken. The notes of 200 new patients who had been invited during the eight-month period January-August 1991 were selected by systematic sampling. The dates that they had attended for their new patient assessment/treatment, first follow-up and second follow-up appointments were recorded. Attendance rates were then calculated using an incomplete life-table method. Patients were censored if they failed to attend their assessment/treatment or review appointments by 1 October 1992. RESULTS: The study demonstrated that 96 per cent of patients attended their first treatment appointment within six months of their appointment date, 91 per cent of first review patients attended within six months, and 88 per cent of second review patients attended within four months. CONCLUSIONS: These findings suggest that there are two distinct groups of defaulters: those who default initially but subsequently re-attend, and those who default completely. We have named these type A and type B defaulters, respectively. This means that attendance within a certain period of time should also be used to monitor clinic attendance in addition to simple mean attendance rates. As patients who default completely may be more likely to have a severe histological lesion, further work is required to identify factors associated with this type of patient.

Adult↗
PubMed1994

Solubilized HLA class I antigen enzyme-linked immunoassay to identify HLA-typing reagents.

The objective of this study was to evaluate the use of sHLA in a solid-phase EIA as a rapid and sensitive way to identify potential IgG HLA class-I-typing reagents. To evaluate the efficacy of the sHLA EIA, we used the assay to screen 259 HLA-A, -B, and -C antisera that our laboratory had procured using the standard NIH LCA. A positive result obtained by the sHLA EIA, which was defined as an EIA ratio of 3 SD above the mean of 91 anti-HLA-negative sera, revealed that 91% (79 of 87) of the A-locus-typing reagents were positive, 96% (150 of 156) of the B-locus antisera were positive, and only 75% (12 of 16) of the C-locus reagents were positive. The typing reagents that were negative by EIA (n = 18) fell into two categories. First, 38% (7 of 18) were negative by sHLA EIA, as they were IgM-typing reagents (NIH LCA reactivity ameliorated by DTT). The second group of the 11 remaining typing reagents had a mean EIA ratio of 1.0 +/- 0.246 (mean +/- 1 SD), which was significantly (P < 0.001) higher than the mean of the 91 negative controls that were used to establish the negative cutoff. The overall sensitivity of the sHLA EIA to detect HLA class-I-directed IgG was 97.2%.

Female↗
PubMed1994

Effects of marijuana history on the subjective, psychomotor, and reinforcing effects of nitrous oxide in humans.

An experiment using marijuana users and non-users was conducted to assess whether the reinforcing, subjective, or psychomotor effects of nitrous oxide were influenced by a subject's drug history. Subjects in the first four sessions sampled 40% nitrous oxide in oxygen and 100% oxygen (placebo), and then over the next three sessions, chose which agent they wished to inhale. Choice distributions between the two groups did not differ significantly, and nitrous oxide choice rates were less than 50% in both groups. However, a history of marijuana use appeared to intensify some of the subjective effects induced by nitrous oxide inhalation.

Administration, Inhalation↗
PubMed1993

Outbreak of SRSV gastroenteritis at an international conference traced to food handled by a post-symptomatic caterer.

In an outbreak of small round structured virus (SRSV) gastroenteritis at an international AIDS conference 67 people were ill with diarrhoea or vomiting, one requiring admission to hospital. Epidemiological investigations demonstrated that the vehicle of infection was food prepared by a foodhandler who was recovering from a mild gastrointestinal illness. The food most strongly associated with illness, coronation chicken, was prepared by the food handler on the second day after symptoms ceased. The investigation confirms the view that foodhandlers may contaminate food with SRSVs after cessation of symptoms and should remain off work until at least 48 h after recovery.

Adolescent↗
PubMed1991

OKT3 first-dose reaction: association with T cell subsets and cytokine release.

Use of the monoclonal antibody OKT3 to prevent or treat allograft rejection has become commonplace. Its administration is often complicated by serious side effects, usually occurring within one to two hours after OKT3 is given, and is termed first-dose reaction. The mechanism underlying these signs and symptoms is poorly defined, but may be related to cytokine release. Twenty-three kidney or kidney/pancreas transplant recipients received OKT3 as treatment of acute rejection. Signs and symptoms occurring after the first dose were observed and quantitated prospectively, and a reaction score was calculated. Blood was drawn immediately before, and at 2 and 24 hours after the first dose of OKT3 for determination of interleukin-2 (IL2), interferon-gamma (IFN gamma), and tumor necrosis factor-alpha (TNF alpha) levels, and flow cytometric analysis of T cell subsets. Two groups were defined based on severity of first-dose reaction. Group 1 patients (N = 11) had very mild reactions (reaction score less than or equal to 3); Group 2 patients (N = 12) had more severe reactions (score greater than or equal to 5). All patients demonstrated a significant rise in serum TNF alpha from baseline to two hours after OKT3 (9 +/- 3 pg/ml to 378 +/- 54 pg/ml, P less than 0.0001), and there was significant correlation between reaction scores and two-hour TNF alpha levels (P = 0.005). Group 2 patients had higher TNF alpha levels at two hours than did Group 1 patients (484 +/- 75 pg/ml vs. 263 +/- 62 pg/ml, P = 0.04). Levels of IL2 and IFN gamma were not elevated at any sampling time.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

Neuropeptide Y and natural killer cell activity: findings in depression and Alzheimer caregiver stress.

A reduction in immune function has been found in patients with a major depressive disorder and in persons undergoing severe life stress. This study investigated the association between increased sympathetic nervous system activity and reduced natural killer (NK) cytotoxicity in depression and Alzheimer caregiver stress. NK activity and plasma concentrations of epinephrine, norepinephrine, and neuropeptide Y were measured in depressed patients (n = 19) and age- and gender-matched controls (n = 19), and in Alzheimer spousal caregivers (n = 48) and matched noncaregiver controls (n = 17). Plasma levels of neuropeptide Y, but not circulating basal levels of catecholamines, were significantly (P less than 0.01) elevated in the depressed patients and in the caregivers compared with respective controls. NK activity was significantly (P less than 0.001) lower in the depressed patients than in their controls, but not different between the caregivers and the noncaregiver controls. Circulating concentrations of neuropeptide Y, but not catecholamines, were inversely correlated (r = -0.31, P less than 0.001) with NK activity. In addition, multiple regression analyses demonstrated that the significant (P less than 0.01) association between neuropeptide Y and natural cytotoxicity was independent of the relative contribution of age and basal and dynamic levels of epinephrine and norepinephrine. These findings suggest that increased sympathetic nervous system activity and the release of neuropeptide Y may be associated with the modulation of NK cytotoxicity.

Alzheimer Disease↗
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↗