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Biomedical subjects

S K Johnson

Publications and source records attributed to S K Johnson.

At least 37 records · Page 2Linked to original sources
PubMed1998

Luteal function and estrus in peripubertal beef heifers treated with an intravaginal progesterone releasing device with or without a subsequent injection of estradiol.

The objectives of this experiment were to determine if treatment of beef heifers with progesterone (P4) using an intravaginal device alone or in combination with estradiol benzoate (EB) would induce estrus and cause development of corpora lutea (CL) with a typical life span. Peripubertal heifers (n = 311) were used when about 40% of the heifers had a functional CL. The heifers were assigned to receive one of the following treatments on Day 0: 1) a sham device for 7 d (C, n = 108); 2) an intravaginal device containing P4 for 7 d (P, n = 102); or 3) an intravaginal device containing P4 for 7 d plus an injection of 1 mg EB 24 to 30 h after device removal (PE, n = 101). Serum concentrations of P4 were determined on Days -7, 0, 8, 15 and 22. Weight and age of the heifers at the start of the trial averaged 292 +/- 45 kg and 365 +/- 38 d, respectively. A greater (P < 0.0001) proportion of the heifers from the PE than P group was in standing estrus (81 vs 37%) and formed normal CL (68 vs 44%) after device removal. Of the heifers exhibiting estrus, a greater (P < 0.05) proportion of PE (94%) than P (80%) heifers was active 1 to 3 d after implant removal. Short-term progesterone treatment increased the proportion of heifers in estrus and those forming normal CL, and adding EB to the progesterone treatment further enhanced these responses.

Administration, Intravaginal↗
PubMed1998

Relation between neuropsychological impairment and functional disability in patients with chronic fatigue syndrome.

OBJECTIVES: To examine the relation between neuropsychological impairment and functional disability in patients with chronic fatigue syndrome, and determine whether the relation is independent of psychiatric factors. METHODS: The subjects were 53 patients with chronic fatigue syndrome and 32 healthy controls who did not exercise regularly. Subjects were administered a structured psychiatric interview and completed questionnaires focusing on depression and functional disability. They also completed a battery of standardised neuropsychological tasks focusing on the cognitive domains that patients with chronic fatigue syndrome experience as particularly difficult: memory (verbal and visual), and attention/concentration. A test score was defined as failing when it was > or =2 SD below the mean of the healthy controls after controlling for demographic factors. RESULTS: Those patients with chronic fatigue syndrome with higher numbers of failing neuropsychological test scores reported significantly more days of general inactivity in the past month than those with fewer failing scores. This result remained significant even after partialling out the contribution of the presence of a comorbid axis I psychiatric episode and the overall level of depressive symptomology. Patients with failing verbal memory scores were particularly functionally disabled compared with those with passing scores. CONCLUSION: A relation was found between cognitive impairment and functional disability which could not be explained entirely on the basis of psychiatric factors.

Activities of Daily Living↗
PubMed1998

Partial regression in primary carcinoma of the lung: does it occur?

AIMS: To study immunohistochemically a group of 28 primary lung cancers which demonstrated histological features reminiscent of those characteristic of regression in malignant melanoma, to determine the phenotype of their immune cell infiltrates. METHODS AND RESULTS: Using a standard s-ABC immunoperoxidase method then quantification by the Leica Q500 MC image analyser, the cellular infiltrate in these tumours, when compared to 67 control cases, showed excess CD3 + T lymphocytes (P < 0.007), with an increase in CD4:CD8 ratio and increased CD68 + macrophages (P = 0.00001). CD57 + natural killer cells and S100 + Langerhans cells were also increased, but not quite significantly (P = 0.048 and P = 0.072, respectively). CONCLUSIONS: This immunophenotype resembles that shown in regressing skin malignancies and suggests a similar process occurring in lung cancer. Regressing lung cancers are associated with a better prognosis than matched controls (P = 0.0034), some showed radiological evidence of growth retardation and the group had an excess of the large cell undifferentiated histological type.

Antigens, CD↗
PubMed1997

Neuropsychology of chronic fatigue syndrome: a critical review.

This article provides a comprehensive and critical review of the neuropsychological and related literature on chronic fatigue syndrome (CFS). Despite the methodological limitations observed in several studies, some consistent findings are noted. The most consistently documented neuropsychological impairments are in the areas of complex information processing speed and efficiency. General intellectual abilities and higher order cognitive skills are intact. Emotional factors influence subjective report of cognitive difficulty, whereas their effect on objective performance remains uncertain. Although the neuropathological processes underlying cognitive dysfunction in CFS are not yet known, preliminary evidence suggests the involvement of cerebral white matter. Directions for future research are outlined.

Fatigue Syndrome, Chronic↗
PubMed1997

Cognitive functioning is impaired in patients with chronic fatigue syndrome devoid of psychiatric disease.

OBJECTIVE: To examine the effect of the presence or absence of psychiatric disease on cognitive functioning in chronic fatigue syndrome. METHODS: Thirty six patients with chronic fatigue syndrome and 31 healthy controls who did not exercise regularly were studied. Subgroups within the chronic fatigue syndrome sample were formed based on the presence or absence of comorbid axis I psychiatric disorders. Patients with psychiatric disorders preceding the onset chronic fatigue syndrome were excluded. Subjects were administered a battery of standardised neuropsychological tests as well as a structured psychiatric interview. RESULTS: Patients with chronic fatigue syndrome without psychiatric comorbidity were impaired relative to controls and patients with chronic fatigue syndrome with concurrent psychiatric disease on tests of memory, attention, and information processing. CONCLUSION: Impaired cognition in chronic fatigue syndrome cannot be explained solely by the presence of a psychiatric condition.

Adult↗
PubMed1997

Verbal learning in amnesic anterior communicating artery aneurysm patients and in patients with multiple sclerosis.

The California Verbal Learning Test (CVLT) was used to examine the qualitative, and quantitative aspects of memory in patients with amnesic anterior communicating artery aneurysm (ACoA) and in patients with multiple sclerosis (MS). The results show that both groups were impaired relative to control participants with respect to acquisition of verbal material. The participants with A CoA exhibited a profound loss of information and emitted a significantly greater number of intrusions and false positives than either control participants or participants with MS. The advantages of using both quantitative and qualitative measures of memory in differentiating various clinical populations are discussed.

Journal Article↗
PubMed1997

The effects of fatigue on neuropsychological performance in patients with chronic fatigue syndrome, multiple sclerosis, and depression.

The effects of fatigue on neuropsychological performance were examined in patients with fatiguing illnesses. Repeated testing with the Paced Auditory Serial Addition Test (PASAT; Gronwall, 1977) was employed over the course of a demanding neuropsychological testing session. It was hypothesized that if fatigue affects performance, one would expect to observe "blunting" of the PASAT practice effect. Fifteen of the study participants live with chronic fatigue syndrome (CFS), 15 with multiple sclerosis (MS), 14 with depression (DEP), and 15 are healthy, sedentary controls. Overall PASAT performance was significantly reduced for CFS and DEP participants compared to controls, whereas mean performance did not differ across the three fatiguing illness groups. Degree of improvement across trials (i.e., practice effect) for the groups did not differ from controls'. Neither subjective fatigue or DEP were significantly related to PASAT performance. These findings suggest that fatigue does not universally impair performance during neuropsychological assessment even in groups in which fatigue is a prominent symptom.

Journal Article↗
PubMed1996

Depression in fatiguing illness: comparing patients with chronic fatigue syndrome, multiple sclerosis and depression.

Because depression is commonly observed in the chronic fatigue syndrome (CFS), the present study sought to determine whether the symptom pattern is similar to that seen in clinically depressed subjects (DEP). Individuals with multiple sclerosis (MS) were chosen as an additional comparison group because MS is a fatiguing illness of known organic etiology. The Beck Depression Inventory (BDI) was used to compare categories of depressive symptomatology. Absolute scores on the BDI were higher for the depressed group on mood and self-reproach symptoms, but were not higher than the CFS group on somatic and vegetative items. Analysis of symptoms as a percentage of total BDI score revealed no significant differences in mood or vegetative items among the three groups. The CFS and MS groups exhibited a significantly lower percentage of self-reproach symptoms than DEP, whereas the DEP group showed a lower percentage of somatic symptoms than the CFS and MS groups.

Adult↗
PubMed1996

Effect of peripheral concentrations of progesterone on follicular growth and fertility in ewes.

The effects of progesterone (P4) on follicular growth and fertility in ewes were examined. In Experiment 1, 22 ewes received either one or three packets of P4 (5 g/packet) or an empty packet subcutaneously (sc) from Days 5 to 15 of the estrous cycle (estrus = Day 0). On Day 6, P4-treated ewes received 12.5 mg of prostaglandin F2 alpha. Follicles > or = 3 mm in diameter were observed via transrectal ultrasonography daily from Day 4 through estrus, corpora lutea (CL) were observed 5 to 7 d after estrus. Ewes with low (LOW; < or = 1 ng/ml; n = 5), intermediate (MED; >1 and <2 ng/ml; n = 10), or normal (NOR; > or =2 ng/ml; n = 7) P4 in jugular plasma on Days 7 through 15 differed in follicular development. The largest follicle at estrus was larger in ewes with LOW vs. MED and NOR P4 (7.8 +/- 0.3 vs. 6.9 +/- 0.2 mm; P < 0.05). Treatments differed in proportions of multiple-ovulating ewes, in which the oldest ovulatory follicle was first observed before Day 10 (LOW: 3 of 3, MED: 6 of 10, NOR: 0 of 5, respectively; P < 0.05). Estradiol was higher early in the treatment period in LOW ewes than in MED and NOR ewes (day x treatment; P < 0.05). In Experiment 2, ewes received 5 mg of P4 in corn oil (low progesterone [LP]; n = 51) or 2 ml of corn oil (CON; n = 49) sc every 12 hr on Days 6 through 14 of the estrous cycle before mating. LP ewes received 15 mg of prostaglandin F2 alpha on Day 6. Mean serum P4 on Days 7 through 15 was 0.6 +/- 0.1 ng/ml in LP and 1.9 +/- 0.1 ng/ml in CON ewes. Eleven LP and 12 CON ewes were scanned daily from Day 4 through mating, and in all ewes (n = 93), CL were counted 10 d after mating and embryos were counted at 25, 40, and 60 d of gestation. In multiple-ovulating ewes, day of cycle of appearance was earlier for the oldest (Day 6.1 +/- 0.8 vs. 10.4 +/- 0.8) but not second oldest (Day 11.7 +/- 1.0 vs. 12.2 +/- 0.9) ovulatory follicles in LP compared with CON ewes. The conception rate was lower in LP (72%) than in CON ewes (98%; P < 0.01). However, numbers of CL 10 d after mating, and in pregnant ewes, numbers of embryos 25 d after mating and lambs born, did not differ with treatment. In summary, low P4 increased the size of the largest follicles and the age of the oldest ovulatory follicles. Embryos resulting from the ovulation of older and younger follicles in the same ewe did not differ in their ability to survive.

Animals↗
PubMed1996

CNS role: an experience in retitling and role clarification.

A LITERATURE REVIEW and survey were undertaken to identify the appropriate titling for individuals in clinical nursing and other advanced practice roles, to establish components in each role, and to determine the educational level necessary for each role. Based upon review and survey results, a CNS task force at the University of Iowa Hospitals and Clinics proposed a change in the titles of nurses in advanced practice at their institution to reflect the American Nurses' Association's definition of advanced practice nursing and recommended graduate level education for these advanced positions. Five specific titles and primary role components were identified: advanced registered nurse practitioners. CNS, education nurse specialist, research nurse specialist, and informatics nurse specialist. Retitling aided in clearly identifying major responsibilities of the position, clarifying role expectations, and creating evaluation tools.

Education, Nursing, Graduate↗
PubMed1996

Selective impairment of auditory processing in chronic fatigue syndrome: a comparison with multiple sclerosis and healthy controls.

The most consistent deficit observed in individuals with Chronic Fatigue Syndrome has been in efficiency of information processing. To examine the possibility of a modality-specific impairment, the present study examined subjects with Chronic Fatigue Syndrome, multiple sclerosis, and healthy controls on an auditory-versus visual-paced serial-addition test. 20 subjects with Chronic Fatigue Syndrome, 20 subjects with clinically definite Multiple Sclerosis, and 20 sedentary healthy controls were compared. One-half of the subjects in each group were administered the Paced Auditory Serial Addition Test and the other half were administered the Paced Visual Serial Addition Test. The group with Chronic Fatigue Syndrome was differentially impaired on the auditory relative to the visual processing task. The group with Multiple Sclerosis was equally impaired on both versions of the task. The results are discussed within the framework of Baddeley's model of working memory.

Adult↗
PubMed1995

Reducing heterogeneity in chronic fatigue syndrome: a comparison with depression and multiple sclerosis.

Chronic fatigue syndrome (CFS) is a heterogeneous illness characterized by a high prevalence of psychiatric problems. We reasoned that we could reduce heterogeneity by excluding patients with psychiatric problems preceding CFS. We compared the functional status, mood, fatigue level, and psychiatric status of this more homogeneous group of CFS patients with the same parameters in patients with mild multiple sclerosis and in patients with major depression or dysthymia. Patients with CFS and those with multiple sclerosis were similar in terms of level of anger, severity of depression, level of anxiety, and frequency of current psychiatric diagnoses. Patients with CFS resembled depressed patients in having impaired vigor and experiencing substantial fatigue and confusion--problems constituting part of the case definition of CFS. The group with CFS was not psychologically vulnerable before the development of this condition and maintained adequate networks of social support despite disabling illness. Stratification to exclude patients with prior psychiatric disease and those with mild CFS allowed us to define a group of patients with CFS who more resembled patients with mild MS than patients with major depression or dysthymia and thus were more likely to have illness with an infectious or immunologic cause. Use of such a stratification strategy should prove important in testing of the viral/immunologic hypothesis of the etiology of CFS.

Adolescent↗
PubMed1995

Perceived changes in adult family members' roles and responsibilities during critical illness.

An exploratory design was used to study the effects of critical care hospitalization on family roles and responsibilities of adult family members and how these effects changed over time. A convenience sample of 52 subjects from pediatric, neonatal, surgical, medical, and cardiovascular intensive care units was used. Data were collected using an open-ended question contained in the Iowa ICU Family Scale (IIFS). Using qualitative techniques, seven themes were identified: (a) Pulling together, (b) Fragmentation of families, (c) Increased dependence, (d) Increased independence, (e) Increased responsibilities, (f) Change in routine, and (g) Change in feelings. These findings indicate that nurses need to implement family-centered interventions such as role supplementation programs or identification of support systems to decrease role strain and role overload in families during a crisis.

Adolescent↗
PubMed1995

Neuropsychological impairments in chronic fatigue syndrome, multiple sclerosis, and depression.

To examine the degree and nature of cognitive impairments in chronic fatigue syndrome, a comprehensive neuropsychological battery was given to patients with chronic fatigue syndrome, multiple sclerosis, depressed patients, and healthy controls. The battery included tests of attention and concentration, information processing speed, verbal and visual memory, intellectual ability, and concept formation. Measures of depression and anxiety were also obtained. The chronic fatigue syndrome group did not differ from the depressed group in overall neuropsychological performance, but differed from the multiple sclerosis and control groups. The most significant impairment was in information processing speed in the chronic fatigue syndrome group. Depression and anxiety were not related to neuropsychological performance. The influence of reduced information processing on other areas of cognition is discussed.

Adult↗
PubMed1994

The nature of memory impairments in multiple sclerosis: acquisition versus retrieval.

The present study was designed to examine whether verbal memory impairment in multiple sclerosis (MS) is attributable to impaired information acquisition or compromised retrieval. Twenty-three MS and 23 control subjects were administered a 10-item verbal list-learning task. Subjects were trained to a specific criterion on the verbal test in order to assure equal information acquisition. Following a 30-min delay, retrieval and recognition performance was evaluated. MS subjects required significantly more trials to reach criterion on the task relative to controls, but the groups did not differ on tests of recall and recognition. Performance was correlated with rate of information processing speed. These results suggest that verbal memory impairment among MS subjects is a consequence of inadequate initial learning and not a function of impaired retrieval.

Adult↗
PubMed1994

Cognitive functioning of patients with chronic fatigue syndrome.

Neuropsychological problems are a distressing and frequent component of the symptom complex associated with chronic fatigue syndrome. Objective assessment of these difficulties is essential to understanding the nature of this illness. Results of the studies discussed in this paper suggest that impaired information processing, rather than primary memory dysfunction, may be at the root of the cognitive problems that afflict so many patients with CFS.

Cognition↗
PubMed1994

Emotional responses of family members during a critical care hospitalization.

BACKGROUND: The needs and satisfaction levels of family members of critically ill patients have received much attention in the literature. The feelings of family members, however, have not been thoroughly investigated. To develop appropriate nursing interventions to assist family members in coping with a critical care hospitalization, accurate information about their emotional response to the situation is needed. OBJECTIVE: To examine emotional responses of family members and their descriptions of supportive behaviors of others during a critical care hospitalization. METHODS: An exploratory design was used to study 52 subjects with critically ill family members in the pediatric, neonatal, medical, surgical and cardiovascular intensive care units in a large tertiary care hospital. The subjects kept daily logs of their feelings and the supportive behaviors of others. Thematic analysis was used to identify major themes. RESULTS: Analysis revealed a broad range of powerful emotions throughout the intensive care unit stay. Negative and positive emotions such as despair and joy were sometimes identified by subjects within a 24-hour period. Although fear, worry, anger and exhaustion were dominant themes during the first 24 hours and when the family received bad news about the patient, there was no pattern of emotional response evident as the stay progressed. Some differences between subjects drawn from the medical and neonatal intensive care units were evident. CONCLUSIONS: The findings suggest that family members of critically ill patients experience deep emotional turmoil throughout the intensive care unit stay. Specific nursing interventions to promote adaptive coping are needed throughout the experience.

Adolescent↗