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91.
H E Prince H Lee E R Jensen P Swanson D Weber L Fitzpatrick M Doyle S Kleinman 《Blood》1991,78(1):169-174
Previously we showed that mononuclear cells from about half of human T-lymphotropic virus (HTLV)-seropositive persons exhibit spontaneous proliferation in vitro. We sought to determine if proliferation was associated with other immunologic changes characteristic of HTLV infection. The parameters assessed were (1) percentages of lymphocytes expressing CD4 and/or CD25 (interleukin-2 receptor), (2) serum levels of soluble CD25, (3) serostatus for other viruses, (4) anti-HTLV antibody levels, and (5) HTLV type determined by polymerase chain reaction or serologic reactivity with type-specific peptides. The proliferation+ HTLV (PROL+) group, proliferation HTLV (PROL-) group, and control group showed similar percentages of CD4+, CD25+, and CD4+CD25+ lymphocytes; serum levels of soluble CD25 were also similar. Antibodies to cytomegalovirus, hepatitis B core, and hepatitis C were present in similar proportions of PROL+ and PROL+ groups. However, a significant association was found between spontaneous proliferation and anti-HTLV antibody levels; sera from 67% of PROL+ persons, but only 18% of PROL- persons, required dilution to yield absorbance values within the linear range of the anti-HTLV antibody assay. In the PROL+ group, persons whose sera required the most dilution had proliferative responses significantly higher than those whose sera required no dilution. The PROL+ and PROL groups were similar with regard to the relative distribution of HTLV-I and HTLV-II infection. These findings indicate that HTLV-related spontaneous lymphocyte proliferation is related to levels of circulating anti-HTLV antibodies, and characterizes both HTLV-I and HTLV-II infection. 相似文献
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Martin Reynolds PhD Eric Sarriot MD PhD Robert Chad Swanson DO Evan Rusoja MD PhD 《Journal of evaluation in clinical practice》2018,24(3):619-628
Systems thinking and reference to complexity science have gained currency in health sector practice and research. The extent to which such ideas might represent a mere passing fad or might more usefully be mobilized to tackle wicked problems in health systems is a concern underpinning this paper. Developing the usefulness of the systems idea requires appreciating how systems ideas are used essentially as constructs conceptually bounded by practitioners. Systems are used for purposes of understanding and engaging the reality of health issues, with the intent of transforming the reality into one that is more manageable, equitable, and sustainable. We examine some manifestations of the systems idea in health practice and the traditions of systems practice that variously make use of them. This provides a platform for proposing a systems thinking in (health) practice heuristic: a learning device supporting how different tools and methods can address “wicked problems” in health praxis. The device is built on the use of “conversation” as a metaphor to help practitioners use systems ideas in tandem with existing disciplinary and professional skills and methods. We consider how the application of the heuristic requires, and helps to develop, human characteristics of humility, empathy, and recognition of fallibility. 相似文献
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97.
Sangil Lee Karisa K. Harland Morgan Bobb Swanson Sara Lawson Elijah Dahlstrom Lance Clemson Elaine Himadi 《The American journal of emergency medicine》2018,36(11):1967-1974
Objectives
Among emergency department (ED) mental health and substance abuse (MHSA) patients, we sought to compare mortality and healthcare utilization by ED discharge disposition and inpatient bed request status.Methods
A retrospective cohort study of 492 patients was conducted at a single University ED. We reviewed three groups of MHSA patients including ED patients that were admitted, ED patients with a bed request that were discharged from the ED, and ED patients with no bed request that were discharged from the ED. We identified main outcomes as ED return visit, re-hospitalization and mortality within 12 months based on chart review and reference from the National Death Index.Results
The average age of patients presenting was 30.5 (SD16.4) years and 251 (51.0%) were female patients. Of these patients, 216 (43.9%) presented with mood disorder and 93 (18.9%) with self-harm. The most common reason for discharge from the ED after an admission request was placed was from stabilization of the patient (n = 138). An ED revisit within 12 months was significantly higher among patients discharged who had a bed request in place prior to departure (54.0%, p < 0.001), than those discharged from the ED (40.9%) or admitted to inpatient care (30.5%). The rate of suicide attempt and death did not show statistical significance (p = 0.55 and p = 0.88).Conclusion
MHSA patients who were discharged from ED after bed requests were placed were at greater risk for return visits to the ED. This implicates that these patients require outpatient planning to prevent further avoidable healthcare utilization. 相似文献98.
Arterial oxygenation associated with portopulmonary hypertension 总被引:2,自引:0,他引:2
STUDY OBJECTIVES: To characterize arterial oxygenation in patients referred to Mayo Clinic for liver transplantation with a diagnosis of portopulmonary hypertension (portoPH). DESIGN: Prospective study. SETTING: Liver transplantation program and pulmonary hypertension clinic in a tertiary referral center. PARTICIPANTS: Twenty consecutive patients with abnormal pulmonary hemodynamics documented by right-heart catheterization (mean pulmonary artery pressure [MPAP] > or = 25 mm Hg, pulmonary vascular resistance [PVR] > or = 120 dyne.s.cm(-5), and pulmonary capillary wedge pressure [PCWP] < or = 15 mm Hg). Liver transplant candidates with normal pulmonary hemodynamics via screening Doppler echocardiography (n = 40) served as control subjects. A subgroup of patients underwent postural and inspired 100% oxygen blood gas analysis, contrast echocardiography, and technetium-labeled macroaggregated albumin ((99m)TcMAA) lung/brain scanning to identify and quantitate the degree of intracardiac or intrapulmonary shunting. MEASUREMENTS AND RESULTS: portoPH was moderate to severe (MPAP > 35 mm Hg) in 18 of 20 patients (90%). Arterial-alveolar oxygen pressure gradient (P[A-a]O(2)) was abnormal (> or = 20 mm Hg) in 16 of 20 patients (80%). PaO(2) was abnormal (< or = 70 mm Hg) in 3 of 20 patients (15%). Pa0(2) was significantly less and P(A-a)O(2) was significantly greater compared to control subjects (p < 0.001). All patients had normal (99m)TcMAA brain uptake (< 6%) and negative transthoracic contrast echocardiographic findings. No significant correlations were found between oxygenation and hemodynamic variables (MPAP, PVR, PVR index, and transpulmonary gradient). CONCLUSIONS: Arterial oxygenation associated with portoPH was frequently abnormal and significantly worse when compared to patients with normal pulmonary hemodynamics by Doppler echocardiography. Hypoxemia, as measured by PaO(2) and P(A-a)O(2), was usually mild even in the setting of moderate-to-severe portoPH. 相似文献
99.
N S Canteras L W Swanson 《Proceedings of the National Academy of Sciences of the United States of America》1992,89(21):10089-10093
The results of anterograde and retrograde axonal transport experiments in the rat indicate that the dorsal premammillary nucleus (PMd) gives rise to a branched pathway ending in the anterior thalamic group and brainstem, like the medial and lateral mammillary nuclei. However, unlike these nuclei, the ascending PMd projection courses through and to the anterior hypothalamic nucleus, and the descending PMd projection ends in the periaqueductal gray, superior colliculus, and adjacent parts of the reticular formation. Also unlike the traditional mammillary nuclei, the PMd does not receive a direct input from the columns of the fornix; instead, it receives a bilateral input from the anterior hypothalamic nucleus, which in turn receives inputs from areas related to the prefrontal cortex, amygdala, and hippocampus. The results provide interesting perspectives on the organization of medial hypothalamic circuits underlying the goal-oriented behaviors associated with hunger, thirst, and reproduction. 相似文献
100.
The relationship of adrenal iodomethylnorcholesterol uptake to indices of adrenal cortical function in Cushing's syndrome 总被引:1,自引:0,他引:1
M D Gross T W Valk J E Freitas D P Swanson D E Schteingart W H Beierwaltes 《The Journal of clinical endocrinology and metabolism》1981,52(6):1062-1066
The adrenal gland uptake of 131I-6-beta-iodomethyl-19-norcholesterol (NP-59) was calculated using a semioperator-independent computer algorithm in 17 patients with Cushing's syndrome (CS). Twelve had ACTH-dependent and 5 had ACTH-independent CS. The mean adrenal gland uptake (percentage of administered dose) of NP-59 was 0.74 +/- 0.18% (range, 0.21-2.02%) in CS and was significantly higher than that of normal subjects (0.33 +/- 0.02%). Patients with the ectopic ACTH syndrome and ACTH-independent CS manifested the highest uptakes (mean, 1.18 +/- 0.08%; range, 0.74-2.02%). In the patients with ACTH-dependent CS, a significant correlation was observed between 24-h urinary free cortisol excretion and NP-59 adrenal gland uptake (r = 0.97, P less than 0.001). No relationship was seen between NP-59 uptake and urinary free cortisol in ACTH-independent CS or between NP-59 uptake and urinary 17-hydroxycorticosteroids, 17-ketosteroids, cortisol secretion rate, plasma cortisol, or ACTH levels in either ACTH-dependent or ACTH-independent CS. We conclude that in addition to localizing the sites(s) of adrenocortical hypersecretion in CS, the level of NP-59 adrenal uptake is a reflection of cortisol excretion in ACTH-dependent disease and may be utilized as another parameter to quantitate adrenal disease activity in CS. 相似文献