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41.
The murine gamma-herpesvirus MHV-68 causes an acute, transient pneumonitis, followed by an infectious mononucleosis (IM)-like illness with splenomegaly, widespread latent infection of B lymphocytes and an expansion of Vbeta4+ CD8+ T cells. CD8+ T cells specific for an H-2Db-restricted epitope were prominent during the acute respiratory infection, but their prevalence declined rapidly during the mononucleosis. In contrast, CD8+ T cells specific for an H-2Kb-restricted epitope, apparently expressed by virus-infected B lymphocytes, were most numerous during the mononucleosis illness and were maintained at relatively high frequencies thereafter. The prevalence of all peptide-specific CD8+ T cells decreased during the expansion of the Vbeta4+ CD8+ population, which did not recognize any peptide epitopes identified and was apparent also in an MHC class I-deficient environment. The CD8+ T cell population recognizing productively infected epithelial cells thus differed substantially from that responding during the IM illness. 相似文献
42.
Andrew A White Donald D Stevenson Ronald A Simon 《Annals of allergy, asthma & immunology》2005,95(4):330-335
BACKGROUND: The blocking effect of controller medications for asthma could have an effect on the outcome of aspirin challenges in patients suspected of having aspirin-exacerbated respiratory disease (AERD). OBJECTIVE: To evaluate whether there was any blocking effect of long-acting beta2-agonists, systemic corticosteroids, and/or inhaled corticosteroids alone or as co-therapy with leukotriene modifier drugs (LTMDs). METHODS: Between 1981 and 2004, 678 patients with suspected AERD were admitted for aspirin challenge and desensitization. All patients had asthma, chronic sinusitis, nasal polyposis, and at least 1 historical reaction to a nonsteroidal anti-inflammatory drug. Asthma controller medications taken during aspirin challenge were recorded and analyzed with respect to their potential effects on 4 possible outcomes of aspirin challenge, namely, naso-ocular reaction, lower airway reaction, classic upper and lower airway reaction, or a negative challenge result. RESULTS: When compared with AERD patients who received no controller medications, the combined use of LTMDs, inhaled corticosteroids, and long-acting beta2-agonists led to a statistically significant change in aspirin challenge outcomes (P = .009), mainly shifting the reaction from a classic upper and lower respiratory tract reaction to naso-ocular reactions only. LTMDs appeared to have the strongest effect (P < .001) in blocking lower respiratory tract reactions. Systemic corticosteroids did not have the same effects. Blocking of both upper and lower respiratory tract reactions to aspirin as a result of taking controller medications did not occur. CONCLUSION: Controller medications are frequently needed to stabilize airways of patients with AERD. LTMDs alone or in combination with other controllers blocked lower respiratory tract reactions during aspirin challenge in some patients with AERD but did not change the overall rate of positive aspirin challenge results and did not lead to false-negative challenges. 相似文献
43.
Andrew White Timothy Bigby Donald Stevenson 《Annals of allergy, asthma & immunology》2006,97(2):190-195
BACKGROUND: Intranasal administration of aspirin-lysine has been used in Europe for the diagnosis of aspirin-exacerbated respiratory disease. It has a low adverse effect profile and is believed to be safer for asthmatic patients, particularly those with a low baseline forced expiratory volume in 1 second, in whom oral aspirin challenge would be contraindicated. Ketorolac, a nonsteroidal anti-inflammatory drug useful for severe pain, is available in the United States in parenteral form. OBJECTIVE: To determine whether ketorolac nasal challenge has acceptable specificity and sensitivity for diagnosing aspirin-exacerbated respiratory disease. METHODS: Twenty-nine patients with suspected aspirin-exacerbated respiratory disease were challenged with nasal ketorolac before oral challenge and desensitization with aspirin. Symptoms, objective changes in nasal examination findings, and peak nasal inspiratory flow values were recorded. Nasal lavage fluid for cysteinyl leukotriene analysis was collected. Ketorolac doses of 2.1, 5.2, or 7.8 mg were administered and compared with the results of oral aspirin challenge. RESULTS: Eighteen patients had a positive challenge reaction to oral aspirin. Ketorolac nasal inhalation had a sensitivity of 78% and a specificity of 64%. Patients in the reactor group had significantly higher levels of cysteinyl leukotrienes after ketorolac challenge than in the nonreactor group. Mild bronchospasm occurred in 3 patients, and 2 of these occurred at higher starting doses of ketorolac. CONCLUSIONS: Nasal ketorolac administration is a reasonably accurate and safe method for diagnosing aspirin-exacerbated respiratory disease. 相似文献
44.
Microencapsulation of CHO cells in a hydroxyethyl methacrylate-methyl methacrylate copolymer 总被引:1,自引:0,他引:1
Chinese hamster ovary fibroblasts, as model cells, have been microencapsulated in a hydroxyethyl methacrylate-methyl methacrylate copolymer (HEMA-MMA) by interfacial precipitation. The polymer containing approximately equal to 75 mol% HEMA, dissolved in polyethylene glycol 200 (PEG 200) was coextruded with the cell suspension (4-6 X 10(5) cells/ml in the alpha-MEM with 10% foetal calf serum +/- Ficoll 400/PBS) through a concentric needle assembly. Polymer solution droplets, containing cells, were blown off the end of the needle assembly by a coaxial filtered air stream into a nonsolvent bath containing phosphate buffered saline (PBS) with 5 ppm Pluronic L101, overlaid with hexadecane. The nascent capsules hang at the hexadecane/PBS interface while the solvent is extracted into the aqueous nonsolvent, to precipitate the polymer around the cells. The resultant capsules were 500 microns-1 mm in diam. with a microporous sponge-like interior, and also very tough and flexible. The cells survived encapsulation based on subculture ability, retention of some fluorescein diacetate (FDA) activity over 5 d and direct light microscopic evidence of cell growth over 10 d after histological sectioning and staining. However, cell growth was not uniformly observed (especially in the FDA assay) and this was attributed to space limitations for growth within the microporous interior. Continued development of this process and adaptation to cells such as pancreatic islets is expected to lead to hybrid artificial organs which are capable of ameliorating metabolic disorders such as diabetes. 相似文献
45.
G. T. Stevenson V. M. Cole J. Summerton H. F. Watts 《Medical oncology (Northwood, London, England)》1984,1(4):275-278
A more effective use of antibody in treating cancer appears to require derivatives with enhanced cytotoxic potential. Working with anti-idiotype antibodies directed against neoplastic lymphocytes, we have shown previously that univalent antibody derivatives with intact Fc-regions can avoid antigenic modulation while retaining the ability to recruit cytotoxic effectors such as complement. Chimeric univalent antibodies represent an extension of this approach. To prepare them Fab′γ from antibody is linked by thioether bonds to half-cystine in normal Ig of the species to undergo immunotherapy. The derivatives FabIgG and FabFc utilize IgG and Fcγ respectively as the effector partners of the antibody Fab′γ. They appear superior to parent antibody in their ability to invoke complement and K-cell killing of target lymphocytes. They show promise of being minimally immunogenic and, because they present homologous Fc, should prove efficient recruiters of host effector functions. 相似文献
46.
47.
Thom E. Snijders Tom P.C. Schlösser Nathanael D. Heckmann Taro Tezuka Rene M. Castelein Rob P. Stevenson Harry Weinans Arthur de Gast Lawrence D. Dorr 《The Journal of arthroplasty》2021,36(6):2184-2188.e1
BackgroundAnterior and posterior pelvic tilt appears to play a role in total hip arthroplasty (THA) stability. When changing from the standing to the sitting position, the pelvis typically rotates posteriorly while the hips flex and this affects the femoro-acetabular positions. This case-control study compares changes in 3-D acetabular cup orientation during functional pelvic tilt between posterior THA dislocations vs stable THAs.MethodsStanding and sitting 3-D cup orientation was compared between fifteen posterior dislocations vs 233 prospectively followed stable THAs. 3-D cup orientation was calculated using previously validated trigonometric algorithms on biplanar radiographs. Those algorithms combine the angles in the three anatomical planes (coronal inclination, transverse version, and sagittal ante-inclination) in the standing position with the change in sagittal pelvic tilt from standing to sitting to calculate the 3-D orientation in the sitting position.ResultsThe standing cup orientation of the dislocated THAs was only characterized by a lower coronal inclination (P = .039). Compared with the controls, from standing to sitting, they showed less posterior pelvic tilt (P < .001). This led to a significant lower coronal inclination (P < .001) and sagittal ante-inclination (P < .001) in the sitting position but similar transverse version (P = .366).ConclusionsComparing posterior THA dislocations to stable THAs, there is a lower increase of all three orientation angles from standing to sitting. This leads to a decreased sitting coronal inclination and sagittal ante-inclination which may lead to an increased risk of impingement ensued by THA instability. By contrast, the transverse version was not significantly different in both positions. This confirms the importance of biplanar data on functional cup orientation.Level of EvidenceDiagnostic, Level III. 相似文献
48.
Kim M. Tsoi Martin Lowe Yusuke Tsuda Johnathan R. Lex Tomohiro Fujiwara Ghassan Almeer Jonathan Gregory Jonathan Stevenson Scott E. Evans Rajesh Botchu Lee M. Jeys 《Clinical orthopaedics and related research》2021,479(2):298
BackgroundPulmonary metastases are a poor prognostic factor in patients with osteosarcoma; however, the clinical significance of subcentimeter lung nodules and whether they represent a tumor is not fully known. Because the clinician is faced with decisions regarding biopsy, resection, or observation of lung nodules and the potential impact they have on decisions about resection of the primary tumor, this remains an area of uncertainty in patient treatment. Surgical management of the primary tumor is tailored to prognosis, and it is unclear how aggressively patients with indeterminate pulmonary nodules (IPNs), defined as nodules smaller than 1 cm at presentation, should be treated. There is a clear need to better understand the clinical importance of these nodules.Questions/purposes(1) What percentage of patients with high-grade osteosarcoma and spindle cell sarcoma of bone have IPNs at diagnosis? (2) Are IPNs at diagnosis associated with worse metastasis-free and overall survival? (3) Are there any clinical or radiologic factors associated with worse overall survival in patients with IPN?MethodsBetween 2008 and 2016, 484 patients with a first presentation of osteosarcoma or spindle cell sarcoma of bone were retrospectively identified from an institutional database. Patients with the following were excluded: treatment at another institution (6%, 27 of 484), death related to complications of neoadjuvant chemotherapy (1%, 3 of 484), Grade 1 or 2 on final pathology (4%, 21 of 484) and lack of staging chest CT available for review (0.4%, 2 of 484). All patients with abnormalities on their staging chest CT underwent imaging re-review by a senior radiology consultant and were divided into three groups for comparison: no metastases (70%, 302 of 431), IPN (16%, 68 of 431), and metastases (14%, 61 of 431) at the time of diagnosis. A random subset of CT scans was reviewed by a senior radiology registrar and there was very good agreement between the two reviewers (κ = 0.88). Demographic and oncologic variables as well as treatment details and clinical course were gleaned from a longitudinally maintained institutional database. The three groups did not differ with regard to age, gender, subtype, presence of pathological fracture, tumor site, or chemotherapy-induced necrosis. They differed according to local control strategy and tumor size, with a larger proportion of patients in the metastases group presenting with larger tumor size and undergoing nonoperative treatment. There was no differential loss to follow-up among the three groups. Two percent (6 of 302) of patients with no metastases, no patients with IPN, and 2% (1 of 61) of patients with metastases were lost to follow-up at 1 year postdiagnosis but were not known to have died. Individual treatment decisions were determined as part of a multidisciplinary conference, but in general, patients without obvious metastases received (neo)adjuvant chemotherapy and surgical resection for local control. Patients in the no metastases and IPN groups did not differ in local control strategy. For patients in the IPN group, staging CT images were inspected for IPN characteristics including number, distribution, size, location, presence of mineralization, and shape. Subsequent chest CT images were examined by the same radiologist to reevaluate known nodules for interval change in size and to identify the presence of new nodules. A random subset of chest CT scans were re-reviewed by a senior radiology resident (κ = 0.62). The association of demographic and oncologic variables with metastasis-free and overall survival was first explored using the Kaplan-Meier method (log-rank test) in univariable analyses. All variables that were statistically significant (p < 0.05) in univariable analyses were entered into Cox regression multivariable analyses.ResultsFollowing re-review of staging chest CTs, IPNs were found in 16% (68 of 431) of patients, while an additional 14% (61 of 431) of patients had lung metastases (parenchymal nodules 10 mm or larger). After controlling for potential confounding variables like local control strategy, tumor size, and chemotherapy-induced necrosis, we found that the presence of an IPN was associated with worse overall survival and a higher incidence of metastases (hazard ratio 1.9 [95% CI 1.3 to 2.8]; p = 0.001 and HR 3.6 [95% CI 2.5 to 5.2]; p < 0.001, respectively). Two-year overall survival for patients with no metastases, IPN, or metastases was 83% [95% CI 78 to 87], 65% [95% CI 52 to 75] and 45% [95% CI 32 to 57], respectively (p = 0.001). In 74% (50 of 68) of patients with IPNs, it became apparent that they were true metastatic lesions at a median of 5.3 months. Eighty-six percent (43 of 50) of these patients had disease progression by 2 years after diagnosis. In multivariable analysis, local control strategy and tumor subtype correlated with overall survival for patients with IPNs. Patients who were treated nonoperatively and who had a secondary sarcoma had worse outcomes (HR 3.6 [95% CI 1.5 to 8.3]; p = 0.003 and HR 3.4 [95% CI 1.1 to 10.0]; p = 0.03). The presence of nodule mineralization was associated with improved overall survival in the univariable analysis (87% [95% CI 39 to 98] versus 57% [95% CI 43 to 69]; p = 0.008), however, because we could not control for other factors in a multivariable analysis, the relationship between mineralization and survival could not be determined. We were unable to detect an association between any other nodule radiologic features and survival.ConclusionThe findings show that the presence of IPNs at diagnosis is associated with poorer survival of affected patients compared with those with normal staging chest CTs. IPNs noted at presentation in patients with high-grade osteosarcoma and spindle cell sarcoma of bone should be discussed with the patient and be considered when making treatment decisions. Further work is required to elucidate how the nodules should be managed.Level of EvidenceLevel III, prognostic study. 相似文献
49.
50.
Active-specific immunotherapy for melanoma 总被引:1,自引:0,他引:1
M S Mitchell W Harel R A Kempf E Hu J Kan-Mitchell W D Boswell G Dean L Stevenson 《Journal of clinical oncology》1990,8(5):856-869
Twenty-five patients with metastatic melanoma were treated with a therapeutic vaccine ("theraccine") consisting of allogeneic melanoma lysates and a novel adjuvant, DETOX (Ribi ImmunoChem Research, Inc, Hamilton, MT). Each patient received 200 antigenic units (20 x 10(6) tumor cell equivalents) subcutaneously on weeks 1, 2, 3, 4, and 6. Clinical responses included one complete remission, three partial remissions, and a long-term (17-month) stability. Two other patients had mixed responses, with partial remissions of numerous subcutaneous nodules. Sites of responsive disease included primarily the skin, but ileal, breast, and a liver metastasis also responded. Removal of residual lesions in patients with partial remissions, whose other lesions had disappeared during treatment, led to long disease-free survivals. The median duration of remission was 17 months, with four of the five responders alive for at least 24 months after treatment. An increase in precursors of cytolytic T cells (CTLs) correlated with clinical outcome, when complete, partial, and mixed responses and long-term stability were considered. The CTLs recognized melanoma-associated antigens on many cell lines, but not other types of tumor or normal lymphocytes. Skin-test reactivity to melanoma antigens and serum antibodies against the melanoma cells was unrelated to clinical response. Toxicity was minimal, restricted largely to minor soreness at the site of injection. Only five patients, four of whom were treated with repeated courses, developed severe granulomas. These results confirm that active-specific immunization with allogeneic lysates of melanoma administered with the adjuvant DETOX can induce immunity to melanoma, and can induce regressions of disease in a proportion of patients with metastatic disease with little toxicity. 相似文献