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排序方式: 共有960条查询结果,搜索用时 31 毫秒
951.
BC McLeod ; TH Price ; H Owen ; D Ciavarella ; I Sniecinski ; MJ Randels ; JW Smith 《Transfusion》1998,38(10):938-943
BACKGROUND: Apheresis donation is considered safe, but the incidence of adverse effects has not been determined in a large multicenter series of donations with modern instruments. STUDY DESIGN AND METHODS: The Hemapheresis Committee of the American Association of Blood Banks devised a uniform questionnaire that asked about 32 specific adverse effects. Transient paresthesia and mild vasovagal events were excluded. A survey was conducted in 1995; 17 centers returned 19,611 responses concerning 250 to 2,000 consecutive apheresis donations per center. RESULTS: Six hundred adverse effects were reported in 428 donations (2.18% of donations). Pain or hematoma at a venipuncture site was the most common response (1.15% of donations); only 203 donations had other (nonvenipuncture) adverse effects (1.04%). Total and nonvenipuncture rates were, respectively, 4.84 and 2.92 percent for 2,295 first donations and 1.78 and 0.77 percent for 17,303 repeat donations (p < 0.001). Rates of nonvenipuncture symptoms in first and repeat donations were, respectively, citrate-induced nausea and/or vomiting, 0.87 and 0.27 percent; tetany, 0.09 and 0.04 percent; pallor and/or diaphoresis, 1.87 and 0.32 percent; vasovagal nausea and/or vomiting, 0.87 and 0.13 percent; syncope and/or seizure, 0.39 and 0.04 percent; and chills and/or rigors, 0.31 and 0.01 percent. The overall rate of donor unconsciousness was 0.08 percent. Hemolysis was reported twice. Clotting or leakage occurred in 0.08 percent of donations, and inability to return blood occurred in 0.16 percent. No life-threatening adverse effects were reported. Procedure-specific nonvenipuncture rates were 1.05 percent of 17,584 platelet donations, 0.67 percent of 594 white cell donations, and 0.37 percent of 1,354 plasma donations. Center-specific rates varied from 0.32 to 6.81 percent of donations for total adverse effects and from 0.11 to 2.92 percent of donations for nonvenipuncture events. CONCLUSION: Apheresis donation is a safe undertaking, suitable for voluntary blood donors, with a very low risk of serious adverse effects. The risk of unconsciousness is lower than that found in many studies of whole-blood donation. 相似文献
952.
BACKGROUND: The clinical utility of polymorphonuclear neutrophil (PMN) transfusion therapy has been compromised, in part, by the inability to obtain sufficient quantities of functional neutrophils from donors. To define the optimal conditions for mobilization of PMNs in granulocyte donors, the effects of granulocyte-colony-stimulating factor (G-CSF) and dexamethasone, separately and in combination, on PMN counts in normal volunteers were compared. STUDY DESIGN AND METHODS: Five normal subjects were randomly assigned to each of the following single-dose regimens in 5 consecutive weeks: 1) G-CSF, 300 micrograms given subcutaneously; 2) G-CSF, 600 micrograms subcutaneously: 3) dexamethasone, 8 mg given orally; 4) G-CSF, 300 micrograms subcutaneously, plus dexamethasone, 8 mg orally; and 5) G-CSF, 600 micrograms subcutaneously, plus dexamethasone 8 mg orally. Venous blood was collected at 0, 6, 12, and 24 hours after drug administration for the determination of absolute neutrophil counts (ANCs). RESULTS: Maximal ANC was achieved at 12 hours after each regimen, except dexamethasone alone (maximum, 24 hours). Dexamethasone significantly increased the maximal ANC induced by either dose of G-CSF alone (p < 0.05). The greatest mobilization of PMNs occurred after the administration of G-CSF (600 micrograms) and dexamethasone (8 mg); the ANC increased from a mean baseline value of 3,594 per microL to 43,017 per microL at 12 hours. All of the drug regimens were well tolerated. CONCLUSION: Dexamethasone significantly increases the level of neutrophilia induced in normal subjects by G-CSF. The combination of dexamethasone and G-CSF (at the dosages used in this study) is a convenient, well-tolerated regimen for the mobilization of PMNs in the peripheral blood of granulocyte donors. Moreover, the optimal quantitative yield of PMNs is likely to be achieved by leukapheresis 12 hours after drug administration. 相似文献
953.
D Darbar MB ChB AB Bridges MB ChB MRCP R Roberts DPhil MRCP TH Pringle MD FRCP 《International journal of clinical practice》1995,49(3):166-167
SUMMARY Cor triatriatum is a rare congenital cardiac malformation, and in its most common form is characterised by a membrane that separates the left atrium into a proximal and distal chamber. First manifestation in adulthood has been reported previously, but at 67 years of age this patient is one of the oldest to present for the first time. It was diagnosed after a probable TIA, episodic vertigo and central retinal artery occlusion. The value of echocardiography in patients with neurological disease of presumed embolic origin is demonstrated here. 相似文献
954.
M Adams ; TH Lee ; MP Busch ; J Heitman ; GJ Marshall ; GF Gjerset ; JW Mosley 《Transfusion》1993,33(6):504-508
Storage of lymphocytes for later use in prospective epidemiologic studies of blood donors and transfusion recipients has been limited by the cost of separating peripheral blood mononuclear cells (PBMCs). When the Transfusion Safety Study began in 1985, it was decided to establish a cell repository of cryopreserved buffy coat (BC) samples, and thus far over 20,000 samples have been accumulated from enrolled subjects. To determine if these specimens could be used for polymerase chain reaction, a simple thawing and pelleting technique for recovering hemoglobin-free total white cells (WBCs) was developed. To validate the technique, parallel analysis was conducted of BCs, whole blood (WB), and PBMC samples from human immunodeficiency virus type 1 (HIV-1)- seropositive subjects. Immediate postthaw cell courts of 29 frozen- thawed (F-T) WB and BC samples averaged 90 percent of the prefreeze (input) values. Representative WBC populations were obtained by immediate pelleting. Amplification of HIV-1 gag sequences from F-T BCs and F-T WB was 94 and 75 percent, respectively, which is as sensitive as that obtained with freshly separated PBMC lysates. Quantitative HIV- 1 proviral load analysis by serial dilution of 23 F-T BCs and 8 WB lysates showed results comparable to those obtained with lysates of fresh PBMCs. Values for WBC differential and immunophenotyping could be applied to express viral load relative to total WBCs, PBMCs, or CD4+ cells. These results establish the basis for simplified virologic analysis of cryopreserved BC or WB specimens. 相似文献
955.
Neutrophil transfusions: kinetics and functions of neutrophils mobilized with granulocyte-colony-stimulating factor and dexamethasone 总被引:4,自引:0,他引:4
BACKGROUND: The collection of adequate numbers of neutrophils (polymorphonuclear leukocytes, PMNs) from normal donors has long hampered the development of neutrophil transfusion therapy. The stimulation of donors with granulocyte-colony-stimulating factor (G- CSF) plus dexamethasone is a promising way of improving PMN collections. STUDY DESIGN AND METHODS: Sixteen normal subjects received G-CSF (600 micrograms subcutaneously) and dexamethasone (8 mg by mouth) 12 hours before leukapheresis. Measurements included PMN morphology, immunophenotype analysis, chemiluminescence, bactericidal activity, in vivo kinetics, and adverse effects. RESULTS: A mean of 77.4 +/− 6.4 × 10(9) PMNs was collected with each leukapheresis; 14 percent were bands. PMNs had increased surface expression of CD11b, CD18, CD14, CD32, and CD64. Bactericidal capacity against Staphylococcus aureus was normal. Inducible respiratory burst was maintained, although the responses to some agonists were diminished. Returned leukapheresis cells labeled with 3H-diisopropylfluorophosphate had a modestly decreased percentage of recovery and circulated with a prolonged half- life. Migration of these cells to skin chambers was approximately equal to that of the subjects' own blood PMNs. Adverse effects included transient bone pain, headache, hunger, and insomnia. CONCLUSIONS: Precollection treatment of leukapheresis donors with G-CSF plus dexamethasone is an effective way to enhance the collection of PMNs with normal or near-normal functional properties for PMN transfusion therapy. 相似文献
956.
TH.M. STARINK R. HAUSMAN L. VAN DELDEN† H. NEERING 《The British journal of dermatology》1977,97(2):167-177
A typical fibroxanthoma is a solitary tumour of the skin, which occurs mostly on sun-exposed areas in elderly people. The diagnosis can only be made with certainty on the typical histological findings, which suggest a bizarre malignant tumour. Although metastasizing tumours are reported in the literature, the authors believe that the true atypical fibroxanthoma is benign. Correct diagnosis obviates the need for unnecessary radical surgery. The possibility of atypical fibroxanthoma should always be considered when a histologically bizarre tumour is found on sun-damaged or irradiation-damaged skin in elderly patients or on previously traumatized sites. In this paper five cases are added to the 346 cases culled from the literature. Electron microscopic investigations in one case demonstrated cells with delicate cytoplasmic fibrils in small bundles. This does not necessarily suggest filaments of myofibroblasts, as has been previously reported. 相似文献
957.
Three groups of glaucoma patients, treated topically with various beta-blocking agents, were studied for mucocutaneous side-effects of long-term therapy. In five of eleven patients with ocular and/or periocular dermatitis as an adverse reaction to long-term treatment with metoprolol eye drops a dermatitis, reproducible by patch tests with pure metoprolol 3%, was demonstrable. Histopathological examination of positive patch tests examined in three cases showed a picture compatible with a delayed type of hypersensitivity. Four atenolol treated patients showed adverse reactions, but negative patch tests to atenolol were found. In addition new data are reported in favour of cross-reactivity between certain beta-blocking agents. 相似文献
958.
959.
Valentina Damato Jakob Theorell Adam Al-Diwani Anne-Kathrin Kienzler Mateusz Makuch Bo Sun Adam Handel Deniz Akdeniz Antonio Berretta Sudarshini Ramanathan Andrew Fower Daniel Whittam Emily Gibbons Nicholas McGlashan Edward Green Saif Huda Mark Woodhall Jacqueline Palace Fintan Sheerin Patrick Waters Maria I. Leite Anu Jacob Sarosh R. Irani 《Proceedings of the National Academy of Sciences of the United States of America》2022,119(24)
Neuromyelitis optica spectrum disorders (NMOSDs) are caused by immunoglobulin G (IgG) autoantibodies directed against the water channel aquaporin-4 (AQP4). In NMOSDs, discrete clinical relapses lead to disability and are robustly prevented by the anti-CD20 therapeutic rituximab; however, its mechanism of action in autoantibody-mediated disorders remains poorly understood. We hypothesized that AQP4-IgG production in germinal centers (GCs) was a core feature of NMOSDs and could be terminated by rituximab. To investigate this directly, deep cervical lymph node (dCLN) aspirates (n = 36) and blood (n = 406) were studied in a total of 63 NMOSD patients. Clinical relapses were associated with AQP4-IgM generation or shifts in AQP4-IgG subclasses (odds ratio = 6.0; range of 3.3 to 10.8; P < 0.0001), features consistent with GC activity. From seven dCLN aspirates of patients not administered rituximab, AQP4-IgGs were detected alongside specific intranodal synthesis of AQP4-IgG. AQP4-reactive B cells were isolated from unmutated naive and mutated memory populations in both blood and dCLNs. After rituximab administration, fewer clinical relapses (annual relapse rate of 0.79 to 0; P < 0.001) were accompanied by marked reductions in both AQP4-IgG (fourfold; P = 0.004) and intranodal B cells (430-fold; P < 0.0001) from 11 dCLNs. Our findings implicate ongoing GC activity as a rituximab-sensitive driver of AQP4 antibody production. They may explain rituximab’s clinical efficacy in several autoantibody-mediated diseases and highlight the potential value of direct GC measurements across autoimmune conditions.Immunoglobulin G (IgG) autoantibodies directed against the extracellular domain of the water channel aquaporin-4 (AQP4) are directly causative in patients with neuromyelitis optica spectrum disorders (NMOSDs) (1–4). AQP4-IgGs are predominantly of the IgG1 subclass, and their major proposed pathogenic mechanism is via complement-mediated damage to the AQP4-rich astrocyte end feet (5). In NMOSDs, patient disability is accrued through discrete clinical relapses, typically affecting the spinal cord and/or optic nerve (6, 7). However, the immunobiology underlying these attacks is poorly understood, and few serum biomarkers can accurately predict relapses (8).Traditionally, ongoing autoantibody production is considered to occur via two broadly discrete cellular pathways: continual germinal center (GC) activity versus long-lived plasma cells (LLPCs) (9). GCs are specialized microenvironments, typically located within secondary lymphoid organs, where antigen-reactive B cells diversify and mature their immunoglobulin genes via somatic hypermutation, with help from specialized lymphoid-resident T follicular helper (Tfh) cells (10). The process of somatic hypermutation is commonly observed alongside a DNA excision process known as class-switch recombination. Together, somatic hypermutation and class-switch recombination can generate high-affinity IgG responses. Autoantigen reactivity of the B cell receptor (BCR) may either arise de novo following somatic hypermutation in GCs or be originally encoded by antigen-reactive germline BCRs expressed by naive B cells (10, 11). Ongoing GC activity may be responsible for the prolonged presence of autoantibodies, such as AQP4-IgGs (9, 12). In an alternative model, LLPCs that successfully exit active GCs and acquire a bone marrow niche may autonomously persist for decades after an autoimmunizing event. These niched LLPCs are thought to secrete >90% of human serum IgG, including a variety of autoantibodies (13, 14).To date, a series of observations suggest that GC activity may play an important role in AQP4-IgG generation. First, close correlations between serum AQP4-IgG levels and AQP4-IgG secreted in vitro by circulating B cells suggest a limited role for LLPCs in AQP4-IgG generation (12, 15). Second, the detection of circulating AQP4-reactive naive B cells identifies a source of cells that could enter GCs and are reported to share clonal relationships with the hypermutated BCRs of intrathecal AQP4-reactive plasma cells (16, 17). Next, annualized relapse rates (ARR) in NMOSDs are robustly reduced by multiple immunotherapies likely to spare nonproliferative CD20− LLPCs, including the anti-CD20 monoclonal antibody rituximab (RTX) (18–20); however, likely because RTX spares the LLPCs, it does not reduce serum AQP4-IgG levels, an observation that presents a potential clinical–serological paradox in a disease with proven pathogenic autoantibodies (21, 22).We hypothesized that the rapid clinical efficacy of RTX observed in patients with NMOSDs may be explained by its direct disruption of active GC reactions, impacting the most affinity matured, and hence pathogenic, B cells and antibodies. However, contradictory data from both human and mouse studies mean that it remains unclear whether RTX effectively depletes B cells within secondary lymphoid organs (23–25). Further, the putative role of GCs in NMOSDs has not been studied directly. In autoimmune diseases of the central nervous system (CNS), the lymphoid organs that drain meningeal lymphatics represent the most plausible anatomical site of active GCs, the deep cervical lymph nodes (dCLNs) (26).To address these concepts, we studied 63 patients with NMOSDs as a prototypical model of an autoantibody-mediated condition. From patients seen as part of routine clinical practice in two specialist NMO centers, we identified clinical relapses in association with proxy measures of an active GC response: class-switch recombination and de novo AQP4-IgM production. Next, to directly sample the secondary lymphoid organs most likely to generate a GC response to neuronal antigens, we aspirated dCLNs from NMOSD patients. These aspirates contained intranodal AQP4-specific B cells and evidence of local, intranodal AQP4-IgG synthesis, both of which were rapidly and efficiently abrogated by RTX over a timescale consistent with clinical remission. Our data present direct insights into the immunological drivers of NMOSD, highlight the effects of RTX in a model of human autoantibody-mediated illness, and provide a platform for the direct analyses of GCs in human autoimmunity. 相似文献
960.
Lauren N. Tronick Heline Mirzakhanian Jean Addington Carrie E. Bearden Tyrone D. Cannon Barbara A. Cornblatt Matcheri Keshavan Daniel H. Mathalon Thomas H. McGlashan Diana O. Perkins William Stone Ming T. Tsuang Elaine F. Walker Scott W. Woods Kristin S. Cadenhead 《Early intervention in psychiatry》2023,17(8):759-770