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21.
Clonal dysregulation of the antibody response to tetanus-toxoid after bone marrow transplantation 总被引:2,自引:0,他引:2
Gerritsen EJ; Van Tol MJ; Van 't Veer MB; Wels JM; Khouw IM; Touw CR; Jol-Van Der Zijde CM; Hermans J; Rumke HC; Radl J 《Blood》1994,84(12):4374-4382
After bone marrow transplantation (BMT), a prolonged dysregulation of humoral immunity can be observed. In the present study, we investigated whether this is reflected in an abnormal production of specific antibodies (Ab) to the T-cell-dependent recall antigen tetanus-toxoid (TT). The study group consisted of children receiving transplants of an unmodified allogeneic graft and of adults receiving either a T-cell- depleted allogeneic or an unmodified autologous BM graft. Findings were compared with those in healthy controls. In pediatric graft recipients, who were routinely revaccinated early after BMT, the Ab response was quantitatively superior to that in adult graft recipients who did not receive early revaccination. In the majority of graft recipients, the time period after vaccination required to reach the peak level of antibodies was prolonged and the number of responding TT-specific B- cell clones was markedly decreased in comparison with controls. In controls, a low frequency of dominant B-cell clones may produce low quantities of homogeneous Ab components (H-Ab) against a heterogeneous background. However, in BM graft recipients, "overshooting" of Ab production by separate B-cell clones was observed, resulting in the development of H-Ab at a relatively high concentration. These abnormalities were present up to 10 years after BMT, irrespective of either the age of the recipient, the modulation of the graft, or the vaccination schedule used. It is hypothesized that the dysregulated Ab production is the consequence of activation of a restricted number of resting memory B cells, present in germinal centers, repopulating gradually after BMT. Our data show that routine revaccination early after BMT improves the humoral immune response. However, because of a clonally dysregulated Ab production, long-lasting qualitative defects may be present even after normalization of Ab titers. 相似文献
22.
Patient-Perceived Pressure from Clinicians for Labor Induction and Cesarean Delivery: A Population-Based Survey of U.S. Women
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Judy Jou Katy B Kozhimannil Pamela Jo Johnson Carol Sakala 《Health services research》2015,50(4):961-981
ObjectiveTo determine whether patient-perceived pressure from clinicians for labor induction or cesarean delivery is significantly associated with having these procedures.ConclusionsPatient-perceived pressure from clinicians significantly predicts labor induction and cesarean delivery. Efforts to reduce provider–patient miscommunication and minimize potentially unnecessary procedures may be warranted. 相似文献
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PurposeBilateral electrical stimulation of anterior nuclei of thalamus (ANT) has shown promising effects on epileptic seizures. However, bilateral implantation increases the risk of surgical complications and side effects. This study was undertaken to access the effectiveness of a stimulation paradigm involving high frequency and low intensity currents to stimulate the left ANT in rats.MethodsMale Sprague-Dawley rats were implanted with electroencephalogram (EEG) electrodes, and an additional concentric bipolar stimulation electrode into either the left or right ANT. The stimulus was a train of pulses (90 μs duration each) delivered with a frequency of 200 Hz and a current intensity of 50 μA. Thalamic stimuli were started 1 h before the first intraperitoneal pilocarpine injection (i.p., 300 mg/kg), and were applied for 5 h.ResultsEEG documented seizure activity and status epilepticus (SE) developed in 87.5% of rats treated with no ANT stimulation after a single dose of pilocarpine. Left ANT stimulation significantly increased the tolerance threshold for pilocarpine-induced EEG seizure activity; 20% of rats developed their EEG documented seizure activity after receiving the first dose, whereas 50%, 10% and 20% of rats did not develop seizure activity until they had received the 2nd, 3rd and 4th pilocarpine injection at 1-h intervals. Moreover, left thalamic stimulation reduced the occurrences of both EEG documented seizure activity and SE induced by single-dose pilocarpine to 25%. However, our result demonstrated that little effect on the occurrence rate of seizures and SE was found when rats received right ANT stimulation.ConclusionsThese results suggest that continuously 5-h left ANT stimulation with high frequency and low intensity currents, beginning from 1 h before the pilocarpine administration, may successfully reduce the occurrence rate of EEG documented seizure activity and SE development in rats. 相似文献
26.
To resolve the apparent conflict between a lubricating glycoprotein,
'lubricin', as the active ingredient in synovial fluid (SF) and surface-
active phospholipid (SAPL) present in SF (and adsorbed to articular
cartilage) as the boundary lubricant reducing friction to such low
physiological levels, lubricin was isolated from bovine SF following the
original procedure of Swann et al. (Arthritis Rheum 1981;24:22-30).
Analysis of the lipid extract by thin-layer chromatography and phosphorus
determination demonstrated a phospholipid component of 11.1 +/- 1.7% (N =
5) which corresponds very closely to the 9.2-13.0% of lubricin which had
hitherto remained unidentified and which has previously been shown to be
transferable to the articular surface to impart lubrication. These results
would appear to resolve any theoretical conflict in that lubricin is,
indeed, an active ingredient within SF. Yet, as a large water-soluble
molecule, it really functions as a carrier for the highly insoluble SAPL
which it deposits on the articular surface as the oligolamellar layer
visualized in previous studies. However, it is this deposited SAPL, rather
than lubricin, which actually lubricates.
相似文献
27.
目的分析影响大学生饮酒模式的因素,针对饮酒教育及酒精政策提出建议。方法采用整群抽样方法,选择来自北京和郑州的530名大学生完成有效问卷调查。采用 Epidata 录入数据,SAS 12.0和 R 2.7.2进行数据描述和分析。结果74.5%的大学生在过去1年内饮过酒,啤酒是饮酒者的主要选择(85.9%),餐馆和家里是饮酒比较频繁的场所,饮用酒多来自同学/朋友及家庭成员提供,25.3%饮酒者并无特别原因饮酒,各有约1/5的饮酒者是出于社交目的或喜欢饮酒的感觉。认为“饮酒有助于社交暠或“饮酒促进交流暠者、父母及同学/朋友饮酒者、来自农村地区或小城镇者及吸烟者更容易发生饮酒行为(均 P 〈0.05),男生大学生、规律饮酒者更容易遭遇强迫劝酒场面、更易发生醉酒(均 P 〈0.05)。超过一半饮酒者出现酒后脸红、肌肉软弱无力等生理反应,饮酒对被调查大学生产生的社会心理影响依次是记忆丧失(23.9%)、宿醉(14.6%)、做了后悔的事(低于10%)等。结论目前大学生仍保持着一种低风险饮酒模式。大学生饮酒教育应提供关于饮酒利弊的科学信息,使其对饮酒保持一种现实的期望。应制定针对性酒精政策和教育鼓励和支持低风险且满足社交功能的饮酒模式,控制高风险饮酒模式。 相似文献
28.
Evelyn T. Chang Kenneth B. Wells Alexander S. Young Susan Stockdale Megan D. Johnson Jacqueline J. Fickel Kevin Jou Lisa V. Rubenstein 《Journal of general internal medicine》2014,29(2):598-606
Background
The high prevalence of comorbid physical and mental illnesses among veterans is well known. Therefore, ensuring effective communication between primary care (PC) and mental health (MH) clinicians in the Veterans Affairs (VA) health care system is essential. The VA’s Patient Aligned Care Teams (PACT) initiative has further raised awareness of the need for communication between PC and MH. Improving such communication, however, has proven challenging.Objective
To qualitatively understand barriers to PC-MH communication in an academic community-based clinic by using continuous quality improvement (CQI) tools and then initiate a change strategy.Design, Participants, and Approach
An interdisciplinary quality improvement (QI) work group composed of 11 on-site PC and MH providers, administrators, and researchers identified communication barriers and facilitators using fishbone diagrams and process flow maps. The work group then verified and provided context for the diagram and flow maps through medical record review (32 patients who received both PC and MH care), interviews (6 stakeholders), and reports from four previously completed focus groups. Based on these findings and a previous systematic review of interventions to improve interspecialty communication, the team initiated plans for improvement.Key Results
Key communication barriers included lack of effective standardized communication processes, practice style differences, and inadequate PC training in MH. Clinicians often accessed advice or formal consultation based on pre-existing across-discipline personal relationships. The work group identified collocated collaborative care, joint care planning, and joint case conferences as feasible, evidence-based interventions for improving communication.Conclusions
CQI tools enabled providers to systematically assess local communication barriers and facilitators and engaged stakeholders in developing possible solutions. A locally tailored CQI process focusing on communication helped initiate change strategies and ongoing improvement efforts.29.
Cheng-Yi Wu I-Ming Jou Wan-Sheng Yang Cheng-Chang Yang Lin-Yu Chao Yi-Hung Huang 《Journal of orthopaedic science》2014,19(5):798-808
Purpose The precise mechanism and pathological role of postlaminectomy/laminotomy fibrosis (PLF) in postoperative neurological deficits have not been established. Many studies use magnetic resonance imaging (MRI) to prove that there is no consistent correlation between PLF and postoperative neurological deficits and back pain (PNDBP). Therefore, we assumed that the direct-compression effect may not be the only factor but that other neurological deficits associated with pathological mechanisms should exist and need more investigation. The purpose of this study was to compare over time the differences and changes in histopathological properties of PLF in rats.Methods We used a rat model with walking-track analysis for neurologic evaluation, grading scale to evaluate PLF, histomorphometric measurements of dura sac diameter, and histological tissue reactions (dura mater and spinal rootlets) juxtaposed to the postlaminectomy/laminotomy defect. The 54 adult Sprague–Dawley rats were divided into laminotomy (n = 18), laminectomy (n = 18), and sham-operation groups (n = 18). All groups were subdivided into three equal subgroups based on different postoperative time points (1, 2, and 3 months). All sections of vertebral column were stained with hematoxylin and eosin and with Masson’s trichrome.Results The results showed that only a slight compression effect reflected by nonsignificant changes in the maximum anterior-posterior diameters within the dura sac, in the walking tract test, and increased grades of PLF over time. In addition, significant pathological inflammatory changes, such as thickening of the dura mater, axonal swelling, and neovascularization, were found in the post-laminectomy/laminotomy groups at each time point.Conclusion Laminectomy-/laminotomy-related inflammation may lead to PLF, and these pathological changes may be the main cause of postoperative neurological deficits. These findings show that research on preventing PLF should include perioperative modulation of inflammatory reactions induced by laminectomy/laminotomy. 相似文献
30.
Chih‐Hsiang Yu Wan‐Ting Chang Shiann‐Tarng Jou Tze‐Kang Lin Ya‐Hsuan Chang Chien‐Yu Lin Kai‐Hsin Lin Meng‐Yao Lu Shu‐Huey Chen Kang‐Hsi Wu Shih‐Chung Wang Hsiu‐Hao Chang Yi‐Ning Su Chia‐Cheng Hung Dong‐Tsamn Lin Hsuan‐Yu Chen Yung‐Li Yang 《Cancer science》2020,111(1):229-238
TP53 alterations are frequent relapse‐acquired mutations in childhood acute lymphoblastic leukemia (ALL). The present study evaluated the clinical significance of relapsed childhood ALL in Taiwan. Diagnostic and/or relapsed bone marrow or peripheral blood was obtained from 111 children with relapsed ALL who were initially treated by using Taiwan Pediatric Oncology Group (TPOG) ALL protocols from January 1997 to May 2018. Mutations were detected by PCR and sequencing, as well as by multiplex ligation‐dependent probe amplification to detect copy number alterations. Copy number and/or sequence alterations of TP53 were detected in 29% (28 of 98) and in 46% (6 of 13) of patients with relapsed B‐cell and T‐cell ALL, respectively. This incidence was much higher than that in several similar studies conducted in Caucasian populations. Seventy percent of all TP53 alterations were gained at relapse in 67 matched samples by back‐tracking matched diagnostic samples. TP53 alterations were associated with lower 5‐year event‐free survival (EFS) and overall survival (OS) rates (P = .013 and P = .0002, respectively). Multivariate analysis confirmed the prognostic significance of TP53 alterations. Forty‐five patients received hematopoietic stem‐cell transplantations post‐relapse. Patients with TP53 alterations (14/45) had inferior 5‐year EFS and OS than patients without TP53 alterations after transplantation (P = .002 and P = .001, respectively). The significance of these TP53 alterations for patients who received transplantations was confirmed by multivariate analysis. In conclusion, TP53 alterations were enriched and useful as prognostic markers in relapsed childhood ALL. 相似文献