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201.
We investigated whether an indirect nuclear terminal deoxynucleotidyl transferase (TdT) immunofluorescence (IF) assay on single cells present in the cerebrospinal fluid (CSF) is more effective than conventional cytomorphology for early detection or exclusion of (minimal) meningeal leukemic infiltration in patients with a TdT+ malignancy. During a 5- year follow-up study, 1,661 consecutive CSF samples from 113 children with a TdT+ acute lymphoblastic leukemia (ALL) (n = 100), a TdT+ acute nonlymphoblastic leukemia (ANLL) (n = 8), or a TdT+ non-Hodgkin's lymphoma (NHL) (n = 5) were analyzed. In 1,511 (91.9%) of 1,643 evaluable CSF samples, the positive and negative findings of both cytomorphology and the TdT-IF assay were concordant. In 47 (2.9%) samples from 28 patients, the cytomorphology was suspect while the TdT- IF assay was negative; follow-up as long as 58 months revealed no CNS leukemia in any patient. In 85 (5.2%) samples, cytomorphology was negative (n = 70) or suspect (n = 15) but TdT+ cells were detected. RBC contamination seriously hampered evaluation in 31 of these 85 samples. From the remaining 54 TdT+ samples from 29 patients, 40 samples preceded overt CNS leukemia in 20 patients. Two consecutive findings of TdT+ cells in the CSF were always followed by overt CNS leukemia. At initial diagnosis, 11 children had TdT+ cells in their RBC-free CSF. In one of these children, morphology was suspect; a repeated lumbar puncture was positive on both assays. Thus, initial CNS leukemia was diagnosed. In the other ten children, morphology was negative. In six of them, CNS leukemia was diagnosed 2 to 20 months later. In 32 other children examined at initial diagnosis, neither TdT+ cells nor blasts were observed in the CSF. In none of these patients was a CNS leukemia diagnosed after a follow-up of 2.5 to 57 months (median 24 months). In 207 control CSF samples from 58 children with TdT- oncologic, hematologic, or infectious diseases, no TdT+ cells could be detected. The TdT-IF assay is easy to perform and is a more reliable diagnostic tool for detection of CNS leukemia at an early stage than is cytomorphology. At initial diagnosis, the finding of Tdt+ cells in a RBC-free CSF sample with a negative cytomorphology is highly predictive for development of overt CNS leukemia.  相似文献   
202.
203.
OBJECTIVE:To investigate the rate of radiographic progression, as measured with the carpo-metacarpal ratio (Poznanski score), during etanercept (ETN) therapy in children with polyarticular juvenile idiopathic arthritis (JIA). METHODS:Patients included in the Italian ETN registry who had a standard radiograph of both hands and wrists in the posteroanterior view made at start of treatment and after 1 year were included in the study. The clinical response was assessed by means of the ACR Pediatric definition of improvement. Radiographic progression was determined by calculating the change in the Poznanski score between the baseline and the 1-year radiographs.RESULTS:A total of 40 patients were studied. The frequency of ACR pediatric 30, 50, and 70 response at 1 year was 77%, 72%, and 50%, respectively. The median change in the Poznanski score between baseline and 1 year was + 0.3 units, meaning that, on average, patients experienced improvement in radiographic progression. CONCLUSION:Our pilot study provides evidence that ETN is potentially capable of reducing the progression of radiographic joint damage in JIA. This finding deserves confirmation in a controlled trial.  相似文献   
204.
Lymphoblasts in bone marrow samples, obtained from 43 children with acute lymphoblastic leukemia at diagnosis, were incubated with 1.0 mumols/L [3H] methotrexate for 24 hours in vitro. Nonexchangeable methotrexate and methotrexate polyglutamates were separated and quantitated. Event-free survival at 5 years was 38% +/- 9% for all 43 patients (27 failures), and 44% +/- 10% for the 35 with non-T, non-B- cell acute lymphoblastic leukemia (20 failures). Of these 35 children, those whose lymphoblasts accumulated more than 100 pmol methotrexate and 500 pmol methotrexate polyglutamates per billion cells experienced better 5-year event-free survival than those whose lymphoblasts did not (65% +/- 12% v 22% +/- 9%, P = .010). This difference characterized "good-risk" patients who were female (P = .014), less than age 7 at diagnosis (P = .005), or had low initial white blood cell counts (less than 20 X 10(9)/L, P = .018). Findings were similar for the 43 children with acute lymphoblastic leukemia and for the "good-risk" children in this total group. Thus, the ability of lymphoblasts to accumulate methotrexate and form methotrexate polyglutamates may be important to the curative properties of current therapy of acute lymphoblastic leukemia in children, particularly for "good-risk" patients. In such patients, inherent rather than acquired drug resistance may be the initial event leading to treatment failure.  相似文献   
205.
OBJECTIVE: The aims of the study were to assess the effect of intra-articular treatment with triamcinolone hexacetonide (TH) in juvenile idiopathic arthritis (JIA) and to investigate whether treatment response correlates with the presence of antinuclear antibodies (ANA) in the serum and/or B CD5+ and T gamma/delta + lymphocytes in the synovial fluid. METHODS: A total of 37 patients (81% females, 56% ANA+) with oligoarticular JIA involving knees were treated with intra-articular injections of TH after failing to respond to NSAIDs for two months. Eighteen patients were treated within 6 months of onset, 19 were treated more than 6 months after onset. RESULT: Mean duration of remission was 13.9 months. Twelve patients (7 ANA+) had stable remission after a single injection; 13 patients (3 ANA+) experienced more than 6 months' remission but subsequently had a relapse; 12 patients (11 ANA+) had a relapse within six months of injection. Of 20 patients treated within 6 months of onset, 17 had stable remission whereas only 8 out of 17 who were treated during relapse attained stable remission (p = 0.03). The mean percentage of T gamma/delta + and of B CD5+ lymphocytes in synovial fluid was the same as in peripheral blood of normal subjects. CONCLUSION: Our data indicate that local treatment with slow-release steroids is very effective in oligoarticular JIA. Prolonged remission was less likely in the presence of ANA positivity, probably because the disease is immunologically more active. Finally, our data suggest that the earlier the treatment, the easier it is to obtain a protracted, and possibly permanent, response.  相似文献   
206.
ObjectiveBaricitinib seems a promising therapy for COVID-19. To fully-investigate its effects, we in-vitro evaluated the impact of baricitinib on the SARS-CoV-2-specific-response using the whole-blood platform.MethodsWe evaluated baricitinib effect on the IFN-γ-release and on a panel of soluble factors by multiplex-technology after stimulating whole-blood from 39 COVID-19 patients with SARS-CoV-2 antigens. Staphylococcal Enterotoxin B (SEB) antigen was used as a positive control.ResultsIn-vitro exogenous addition of baricitinib significantly decreased IFN-γ response to spike- (median: 0.21, IQR: 0.01–1; spike+baricitinib 1000 nM median: 0.05, IQR: 0–0.18; p < 0.0001) and to the remainder-antigens (median: 0.08 IQR: 0–0.55; remainder-antigens+baricitinib 1000 nM median: 0.03, IQR: 0–0.14; p = 0.0013). Moreover, baricitinib significantly decreased SEB-induced response (median: 12.52, IQR: 9.7–15.2; SEB+baricitinib 1000 nM median: 8, IQR: 1.44–12.16; p < 0.0001). Baricitinib did modulate other soluble factors besides IFN-γ, significantly decreasing the spike-specific-response mediated by IL-17, IL-1β, IL-6, TNF-α, IL-4, IL-13, IL-1ra, IL-10, GM-CSF, FGF, IP-10, MCP-1, MIP-1β (p ≤ 0.0156). The baricitinib-decreased SARS-CoV-2-specific-response was observed mainly in mild/moderate COVID-19 and in those with lymphocyte count ≥1 × 103/µl.ConclusionsExogenous addition of baricitinib decreases the in-vitro SARS-CoV-2-specific response in COVID-19 patients using a whole-blood platform. These results are the first to show the effects of this therapy on the immune-specific viral response.  相似文献   
207.
The resting and exertional haemodynamic effects of acute and chronic discontinuous (one tablet every 6 h) treatment with 5 mg of buccal nitroglycerin (BN) have been assessed in nine postinfarction heart failure patients. At rest, pulmonary artery (PAP), pulmonary wedge (PWP), and right atrial pressures (RAP) were reduced by 42%, 55% and 77%, respectively, after the first dose and by 26%, 32% and 45%, respectively, after the chronic (three weeks) treatment with BN. During exercise, at the same workload, PAP, PWP and RAP were significantly reduced by 44%, 54% and 62%, respectively, after acute treatment and by 28%, 34% and 44%, respectively, after chronic treatment. The maximal workload (Kgm) increased by 179% and 166% and the exercise time increased by 78% and 71% after acute and chronic therapy, respectively. At the maximal workload, after acute BN, overall haemodynamics were better than in the basal state. PAP, PWP and RAP were still reduced by 19%, 31% and 31%, respectively, after acute treatment, while after chronic phase the results did not differ from control. The severity of cardiac failure, according to the Weber classification, was reduced by acute and chronic therapy. We can conclude that the buccal nitroglycerin showed clear efficacy in improving overall haemodynamic parameters both at rest and during exercise in post-myocardial infarction patients with heart failure. The discontinuous treatment maintained the effect of nitroglycerin without clear evidence of tolerance during chronic therapy.  相似文献   
208.
JJ Sciubba 《Oral diseases》2016,22(8):740-744
Past the point of no longer being able to control malignancies of the oral cavity and head and neck, the decision‐making process must shift to one that essentially concerns itself with creating comfort for the patient. The role of family, physicians, and other caregivers becomes, in many ways, more directed as active neoplasia‐related concerns become less relevant. Challenges remain significant in terms of continuing management of prior treatment‐related side effects and functional impairments to providers concerning themselves with maintenance of dignity, honoring the wishes of the family, and creating full understanding of on the part of all parties concerned what the goals of treatment cessation and palliation are key as death approaches.  相似文献   
209.
Fibrinolytic properties of a human endothelial hybrid cell line (Ea.hy 926)   总被引:7,自引:1,他引:7  
Emeis  JJ; Edgell  CJ 《Blood》1988,71(6):1669-1675
The fibrinolytic characteristics of the endothelial hybrid cell line EA.hy 926, established by fusing a human umbilical vein endothelial cell with a human carcinoma cell line, were studied. The hybrid cell line produced large amounts of tissue-type plasminogen activator (t- PA), plasminogen activator inhibitor type 1, and a small amount of urokinase. All plasminogen activator present in conditioned medium was complexed with inhibitor because the cells secreted plasminogen activator inhibitor in excess over plasminogen activator and no activator activity was detectable in conditioned media by direct activity assays. t-PA activator activity was, however, demonstrable in conditioned media after treatment with sodium dodecyl sulfate, in agreement with t-PA antigen determinations. Increased plasminogen activator inhibitor activity could be induced by incubating the cells in the presence of endotoxin or microtubule inhibitors, whereas increased t-PA activity could be induced by microtubule inhibitors. Interleukin-1 had no effect. The fibrinolytic characteristics of the hybrid cell line were stable for at least 30 passages. The perpetual human hybrid cell line EA.hy 926 therefore may be a useful tool for the study of fibrinolysis in cultured endothelial cells.  相似文献   
210.
A bleeding disorder with absent collagen-induced platelet aggregation and adhesion has been described in a patient whose platelets failed to express surface glycoprotein Ia. We studied the interaction of her platelets with subendothelium in an annular perfusion chamber and the interaction with purified human collagen type III in a rectangular perfusion system under flow conditions. Platelet adherence was almost completely absent both at low and high shear rates. The few platelets which adhered remained in the contact stage without subsequent spreading and aggregate formation. Addition of a monoclonal antibody, which was directed against the von Willebrand moiety of FVIII-VWF, to the blood, completely abolished platelet adherence at high shear rates and had a partial effect at low shear rates. These data indicate that von Willebrand factor plays a role in the initial attachment (contact stage) of platelets to subendothelium. We conclude that the bleeding disorder and excessively prolonged bleeding time in our patient are caused by a new specific defect of the platelet-vessel wall interaction.  相似文献   
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