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901.
Asynchronous antigen expression in B lineage acute lymphoblastic leukemia   总被引:4,自引:1,他引:4  
Cell surface phenotypes of 113 B lineage acute lymphocytic leukemia (ALL) cases, defined by the presence of HLA-DR and at least one B-cell- specific antigen (either CD19, CD20, or CD22), were compared with antigen-defined stages of normal B lymphocyte development. The cases were first evaluated for expression of HLA-DR, CD19, CD34, CD10, CD20, and CD22 by indirect one-color immunofluorescence. Pairwise comparisons of cell surface marker expression were performed for each leukemic sample: no correlations were observed for paired antigen expression on the leukemic samples using antigens expressed either early or late during normal B lymphoid development. Complete immunophenotypes of the cases were then compared with normal B-cell developmental stages. Sixteen different complete immunophenotypes were observed on the leukemias that were not found in normal marrow; at least 78% of the cases demonstrated such "asynchronous" combinations of B lymphoid- associated differentiation antigens. Several samples were subsequently studied by two-color immunofluorescence, and the presence of doubly labeled cells with "asynchronous" antigen combinations was confirmed. These results indicate that the majority of B lineage leukemias exhibit "developmental asynchrony," as compared with normal marrow B cells. The data further suggest that ALL cases do not accurately represent cells arrested at the stage where the leukemogenic event occurred. Rather, ALL appears to be a disease in which there may be maturation of leukemic blasts; but this maturation is "asynchronous" when compared with the normal developmental process.  相似文献   
902.
903.
904.
A total of 232 leukaphereses were performed with a continuous flow (CFC) of 89 donors related to recipients to obtain granulocytes for infected granulocytopenic recipients. One hundred fifteen runs were done without pretreatment of the donors and were used as controls. Pharmacological pretreatment of the remaining one hundred seventeen donors included Prednisone, given in an oral dose (50 mg) the evening prior to the run, and/or 250ml of 6 per cent hydroxyethyl starch added to the input line of the CFC throughout the run. A median of 9.2 liters of donor blood was processed with each run. The pretreatment of the donors with Prednisone plus the addition of HES to the input line significantly increased the number of granulocytes collected. Donors tolerated the leukapheresis procedure well, and no significant side effects were associated with Prednisone or HES administration. Early and frequent use of such granulocytes was effective in the short-term control of fever in the granulocytopenic recipients who failed to respond to 48 hours of broad spectrum antibiotic coverage.  相似文献   
905.
Background: Solana® (Quidel) is a new rapid (<40 min.) point-of-care (POC) test for qualitative detection of Trichomonas vaginalis (TV) DNA. The assay has two steps: 1) specimen preparation, and 2) amplification and detection using isothermal Helicase-Dependent Amplification (HDA). The objective was to demonstrate the performance of Solana for vaginal swabs and female urines based on comparison to wet mount and TV culture. Performance was also compared to the Aptima-TV assay.

Methods: Urine and four clinician-collected vaginal swabs were collected. The first two were used for FDA composite reference (wet mount; InPouch TV Culture). The third swab was used for Solana. Sensitivity/specificity were based on the reference method. A specimen was considered positive if either test was positive. The fourth swab was for Aptima-TV.

Results: Vaginal swabs and urines were obtained from 501 asymptomatic and 543 symptomatic women. Prevalence of TV by was 11.5%. For swabs, Solana® demonstrated high sensitivity and specificity from asymptomatic (100%/98.9%) and symptomatic (98.6%/98.5%) women, as well as for urines from asymptomatic (98.0%/98.4%) and symptomatic (92.9%/97.9%) women, compared to the reference method. Compared to Aptima-TV, the sensitivity/specificity was 89.7%/99.0% for swabs and 100%/98.9% for urines.

Conclusion: The Solana® assay performed well compared to the reference assays.  相似文献   

906.
Muckle-Wells syndrome (MWS) is a rare autosomal dominant hereditary disorder characterized by chronic recurrent urticaria, arthralgia, sensorineural deafness, and in some cases nephropathy due to amyloidosis (AA type). We report a 21-year-old woman and her father, both suffering from this syndrome, in whom elevated serum levels of IL- 6 could be documented during the flares of urticaria, and discuss the relevance of this finding for MWS.   相似文献   
907.

Introduction

The objective of the present study was to compare the health-related quality of life (HR-QoL) of survivors from severe sepsis and septic shock with HR-QoL in others who survived critical illness not involving sepsis.

Methods

From March 1997 to March 2001, adult patients in an eight-bed medical/surgical intensive care unit (ICU) of a tertiary care hospital admitted with severe sepsis or septic shock (sepsis group; n = 305) were enrolled and compared with patients admitted without sepsis (control group; n = 392). Patients younger than 18 years (n = 48) and those whose ICU stay was 1 day or less (n = 453) were excluded. In addition, patients exhibiting nonsevere sepsis on admission were excluded (n = 87). Finally, patients who developed nonsevere sepsis or severe sepsis/septic shock after admission were also excluded (n = 88).

Results

In-hospital mortality rates were 34% in the sepsis group and 26% in the control group. There were no differences in sex, age, main activity (work status), and previous health state between groups. Survivors in the sepsis group had a significantly higher Acute Physiology and Chronic Health Evaluation II score on admission (17 versus 12) and stayed significantly longer in the ICU. A follow-up appointment was held 6 months after ICU discharge, and an EQ-5D (EuroQol five-dimension) questionnaire was administered. A total of 104 sepsis survivors and 133 survivors in the control group answered the EQ-5D questionnaire. Sepsis survivors reported significantly fewer problems only in the anxiety/depression dimension. Although there were no significant differences in the other dimensions of the EQ-5D, there was a trend towards fewer problems being reported by sepsis survivors.

Conclusion

Evaluation using the EQ-5D at 6 months after ICU discharge indicated that survivors from severe sepsis and septic shock have a similar HR-QoL to that of survivors from critical illness admitted without sepsis.  相似文献   
908.
We studied the capacity of cultured mouse peritoneal macrophages to generate superoxide anion (O(2-)), the initial product of conversion of oxygen to microbicidal species, during phagocytosis of opsonized zymosan or upon contact with the membrane-active agent phorbel myristate acetate (PMA). Macrophages from mice infected with Bacille Calmette-Guerin (BCG) or injected intraperitoneally with thioglycollate broth or endotoxin, released up to 12 times more O(2-) than did resident peritoneal macrophages, depending upon the cell type and whether the stimulus was zymosan or PMA. There was little if any O(2-) release from resting (unstimulated) macrophages. The density of cells on culture dishes was an important variable since crowding of the dish markedly reduced the efficiency of O(2-) production. The enhanced O(2-) release of chemically elicited and infection-activated macrophages was noted after stimulation with a wide range of concentrations of PMA and zymosan, at all time points studied (up to 120 min), and with cells maintained for 140 rain to 16 days in culture. The O(2-) response of resident cells improved twofold to zymosan and ninefold to PMA during the first 3 days in culture. The capacity to release O~ appears to be limited to actively phagocytic cell types: murine macrophage-like tumor lines and cultured human monocytes released O(2-) when stimulated by PMA or zymosan, fibroblast and endothelial lines and embryo-derived cells did not. Activity of superoxide dismutase, which removes O(2-), was not detectable in culture supernates of any cell type, and thus, differences in detectable O(2-) could not be attributed to variations in the release of this enzyme. We conclude that the phagocytosis- associated respiratory burst is significantly enhanced in mononuclear phagocytes obtained ai~r chemical inflammation or BCG infection. Increased capacity to generate O(2-) and other oxygen radicals during phagocytosis could contribute to the improved microbicidal and tumoricidal activity of activated macrophages.  相似文献   
909.
The global lockdown measures implemented due to the COVID-19 pandemic have nearly always had negative consequences for patients with multiple sclerosis (MS).ObjectiveWe compared the social and professional effects of confinement on patients with MS in 2 very different populations, from Spain and China.MethodsQuestionnaires were administered to a group of patients with MS who consulted at the MS unit of Vithas hospital (DINAC Foundation) in Seville, and patients with MS attended in several provinces of China in April 2020, with the aim of analysing the differences and similarities between populations in the social and professional effects of confinement. To this end, a database was created and subsequently analysed.ResultsThe Chinese population includes a higher proportion of younger patients and no differences were identified regarding sex. Most of the variables studied behaved in the same way in both patient populations. Spanish patients presented a lesser impact (30.7%) on their socio-economic situation than Chinese patients (44%) (P < .05). There were no significant differences between populations in the remaining variables. Social networks were widely used in the majority of patients from both populations.ConclusionsThe social and professional consequences of the pandemic were very similar in both groups; the use of social networks and family support was also similar. Spanish patients seem to present greater economic stability, perhaps due to the social support they receive.  相似文献   
910.
Background : Patent ducti arteriosi (PDAs) are more frequent and larger at high altitude than at sea level. A novel PDA closure device, the Nitocclud PDA‐R, is designed specifically for both large and medium size PDAs. The initial clinical experience with a new nitinol‐based device in high altitude patients with large PDAs is described. Methods : The Nitocclud PDA‐R is a self‐expandable, self‐centering, repositionable occluder made of one nitinol wire without use of welding. It contains several polyester membranes, is delivered with a central guide wire and is released by retraction of the central wire into the delivery catheter. The efficacy of this device was evaluated at several high altitude centers. Results : Fifty‐one patients without other congenital cardiac defects underwent transcatheter closure of PDA. Complete occlusion of the PDA was achieved in 98% of the patients. Nearly 49% of the patients had no shunt immediately after device implantation. Echocardiography revealed a complete closure rate by Doppler interrogation of 69% after 24 hr, 96% after 6 months, and 98% after 1 year. In two cases, device embolization was observed after release, and in both cases the device was easily retrieved with standard interventional techniques. There have been no episodes of delayed device migration, endocarditis, hemolysis, wire fracture, device disruption, or death. Conclusions : The Nitocclud PDA‐R device is safe and effective and can easily close very large PDAs. This device has a high rate of complete occlusion within 1 year and is easily retrieved if embolized. © 2011 Wiley Periodicals, Inc.  相似文献   
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