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1.
Crosslineage T-cell receptor delta (TCR delta) rearrangements are widely used as tumor markers for the follow up of minimal residual disease in childhood B-precursor acute lymphoblastic leukemia (ALL) by polymerase chain reaction (PCR). The major drawback of this approach is the risk of false-negative results due to clonal evolution. We investigated the stability of V delta 2D delta 3 rearrangements in a group of 56 childhood B-precursor ALL patients by PCR and Southern blot analysis. At the PCR level, V delta 2D delta 3-to-J alpha rearranged subclones (one pathway for secondary TCR delta recombination) were demonstrated in 85.2% of V delta 2D delta 3-positive patients tested, which showed that small subclones are present in the large majority of patients despite apparently monoclonal TCR delta Southern blot patterns. Sequence analysis of V delta 2D delta 3J alpha rearrangements showed a biased J alpha gene usage, with HAPO5 and J alpha F in 26 of 32 and 6 of 32 clones, respectively. Comparison of V delta 2D delta 3 rearrangement status between diagnosis and first relapse showed differences in seven of eight patients studied. In contrast, from first relapse onward, no clonal changes were observed in six patients studied. To investigate the occurrence of crosslineage TCR delta rearrangements in normal B and T cells, fluorescence-activated cell sorter-sorted peripheral blood CD19+/CD3- and CD19-/CD3+ cell populations from three healthy donors were analyzed. V delta 2D delta 3 rearrangements were detected at low frequencies in both B and T cells, which suggests that V delta 2-to-D delta 3 joining also occurs during normal B-cell differentiation. A model for crosslineage TCR delta rearrangements in B-precursor ALL is deduced that explains the observed clonal changes between diagnosis and relapse and is compatible with multistep leukemogenesis of B-precursor ALL.  相似文献   
2.
We used a colorimetric polymerase chain reaction (PCR)-based assay in kit form to detect directly human immunodeficiency virus type 1 (HIV-1) proviral gag sequences in peripheral blood cells from 68 healthy blood donors, 51 subjects at risk for HIV infection, 122 patients with HIV-1 infection, 11 patients with indeterminate Western blot (immunoblot) results, 4 blood donors HIV-1 positive by enzyme immunoassay, and 13 children born to HIV-1-seropositive mothers. The results obtained in the blood donors and HIV-1-infected patients demonstrated the high degree of diagnostic specificity and sensitivity of the PCR method. HIV-1 infection was excluded in 10 of the 11 patients with indeterminate Western blot results and in all four enzyme immunoassay-positive blood donors. A diagnosis of HIV infection was ruled out by negative PCR results in 5 of 13 children from seropositive mothers, which excluded vertical transmission of the infection in these cases; these children were younger than 3 months and had positive serological results. Two at-risk patients with negative serological results had positive PCR results. All results were confirmed by conventional PCR. In conclusion, colorimetric PCR, which is commercially available in kit form, is an easy and reliable technique that can be used to detect proviral HIV-1 genomes in blood cells, and despite the limitations owing to HIV genome variability, it is useful in the clinical setting for the diagnosis of HIV infection in selected categories of patients.  相似文献   
3.
The world's first deliveries of normal babies after use of flow cytometric separated human sperm cells (MicroSort) for preconception gender selection are reported. Offspring were of the desired female gender in 92.9% of the pregnancies. Most of these pregnancies and births were achieved after simple intrauterine insemination.   相似文献   
4.
Detecting pre-ovulatory luteinizing hormone surges in urine   总被引:2,自引:1,他引:2  
The study objectives were to determine (i) if pre-ovulatory luteinizing hormone (LH) surges, undetected in urine by two immunoradiometric assays (IRMA), were detectable by an ultrasensitive immunofluorometric assay (IFMA) and (ii) the influence of creatinine adjustment on the detection and timing of the urinary LH surges. Daily urine specimens were contributed by healthy 25-36 year old volunteers during 14 ovulatory menstrual cycles for an epidemiological study conducted in 1983-1985. Specimens were selected as having been previously assayed by two IRMA without consistently detecting LH surges. These urine specimens were remeasured using an IFMA and adjusted for creatinine concentration. IFMA measurements revealed unambiguous LH surges in all cycles. Adjusting IRMA urinary LH values for creatinine concentrations revealed previously undetected LH surges in four of eight cycles. Creatinine adjustment also altered the timing of IRMA and IFMA LH surges by 1-5 days. These results demonstrate an IFMA that detects pre- ovulatory LH surges in unpreserved, frozen urine from cycles where such surges were previously undetectable. Further, creatinine adjustment can markedly affect detection and timing of the onset and peak of the urinary LH surge. While our analysis suggests that this adjustment improves the validity of the LH measure, this requires further investigation.   相似文献   
5.
Lung carcinoma remains one of the most frequent and aggressive human neoplasms. Fortunately, in the last decades, the increasing knowledge of the molecular mechanisms leading to cancer development has allowed the use of targeted therapies with improvement of prognosis in many patients. Clinical management has also changed after the introduction of endobronchialultrasonographic bronchoscopy that allows a conservative staging of lung tumors, avoiding the need of mediastinoscopy for lymph node staging. Lung pathologists and cytopathologists are facing the challenge of giving the more comprehensive prognostic and predictive information with ever smaller tissue or cytological samples. The aim of this review is to summarize the molecular testing for non-small cell lung carcinoma and how pathologists can contribute to the patient's outcome with a conscious management of biological samples.  相似文献   
6.
7.
目的:对松花粉和松针提取物在亲脂性抗氧化模型系统中的抗氧化能力和机制进行研究。方法:采用铜诱导的LDL氧化反应模型和Rose Bengal反应模型分别进行评价。结果:松花粉乙醇提取液具有较好的自由基链式反应阻断剂的作用,有效地推迟人血浆中低密度脂蛋白(LDL)氧化生成共轭二烯。松针乙醇提取液对LDL的保护作用优于松花粉。在Rose Bengal系统中,松花粉以清除自由基和螯合铜的两种机制抑制脂质过氧化反应的发生,而松针主要作为自由基清除剂发挥抗氧化作用。结论:松花粉和松针在两个亲脂性体外模型中均发挥很好的抗氧化能力,而抗氧化机制不尽相同。  相似文献   
8.
PURPOSE: Point mutations within the ABL kinase domain of the BCR-ABL gene have been associated with clinical resistance to imatinib mesylate in chronic myeloid leukemia (CML) patients. To shed further light on the frequency, distribution, and prognostic significance of ABL mutations, we retrospectively analyzed a homogeneous cohort of late chronic phase CML patients who showed primary cytogenetic resistance to imatinib. PATIENTS AND METHODS: Using denaturing high-performance liquid chromatography (D-HPLC) and sequencing, we screened for ABL mutations in a total of 178 bone marrow and/or peripheral blood samples from 40 late chronic phase CML patients homogeneously treated with imatinib 400 mg/d, who did not reach a major cytogenetic response at 12 months. RESULTS: Mutations were found in 19 of 40 patients (48%). Mutations were already detectable by D-HPLC at a median of 3 months from the onset of therapy. The presence of a missense mutation was significantly associated with a greater likelihood of subsequent progression to accelerated phase/blast crisis (P = .0002) and shorter survival (P = .001). Patients carrying mutations falling within the P-loop seemed to have a particularly poor outcome in terms of time to progression (P = .032) and survival (P = .045). CONCLUSION: Our results show that, irrespective of the hematologic response, monitoring for emerging mutations in the first months of therapy may play a role in detecting patients with worse prognosis, for whom a revision of the therapeutic strategy should be considered.  相似文献   
9.
Objectives : to investigate the utility of assessing Health-Related Quality of Life (HRQoL) in a large group of subjects participating in a screening program for aneurysm and the relationship between HRQoL, diagnosis of aneurysm and related risk factors.

Methods : subjects involved in this screening program were submitted the EQ-5D questionnaire to report their own HRQoL. HRQoL was reported also a second time by the subjects who were diagnosed with aneurysm during screening and who returned for a monitoring follow up visit a few months later. We evaluated compliance with HRQoL data collection and performed multiple regression analyses in order to investigate the possible relationship between demographic and clinical data with HRQoL.

Results : 1,633 subjects screened (6.1% diagnosed with aneurysm) and 125 subjects diagnosed with aneurysm and attending a follow-up visit reported their HRQoL. Completion of the EQ-5D questionnaire was well accepted by both physicians and subjects undergoing screening. HRQoL was not significantly different between the screening and follow - up visits, on adjusting for age and sex. At the screening visit, HRQoL was associated with ASA class, heart condition, BMI and respiratory diseases. No associations were found at the follow-up visit.

Conclusion : Assessing HRQoL in screening programs is feasible and well accepted and add useful information on health of large numbers of subjects from general population. This could be considered as a routine approach to optimizing the informative role of screening programs in guiding other investigations or interventions.  相似文献   
10.
Rheologic predictors of the severity of the painful sickle cell crisis   总被引:4,自引:0,他引:4  
Ballas  SK; Larner  J; Smith  ED; Surrey  S; Schwartz  E; Rappaport  EF 《Blood》1988,72(4):1216-1223
Deformable sickle erythrocytes have been reported by Mohandas and Evans to be more adherent to vascular endothelium than rigid irreversibly sickled cells (ISC). To define the clinical implications of this finding we have determined genetic, hematological, clinical, and rheological characteristics of sickle erythrocytes obtained from 65 patients with sickle cell anemia and fetal hemoglobin (Hb F) levels less than 15%. The alpha-globin gene number had a significant effect on the hematological parameters, the percentage of dense cells, ISC number, and HB A2 levels. The presence or absence of alpha thalassemia, however, had no effect on the frequency and severity of the sickle cell painful crisis (r = 0.06, P greater than .05). RBC deformability, determined by an ektacytometer, showed great heterogeneity among patients with three or four alpha-globin genes. Linear regression analyses of the data showed significant positive correlation of the frequency and severity of the painful crisis with RBC deformability (r = 0.49, P less than .001), and negative correlations with the percentage of dense cells (r = -0.37, P = .002), and the percentage of ISC (r = -0.46, P less than .001). We propose that the more deformable the sickle RBC are, the greater their adherence to vascular endothelium, and the more they cause vaso-occlusive crises, RBC deformability and the percentage of dense cells (or ISC) seem to have a predictive value of the frequency and severity of painful crises in sickle cell anemia.  相似文献   
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