血清学标志阴性的非甲～戊型肝炎的病原学研究

目的对血清学标志阴性的非甲～戊型肝炎进行病原学研究。方法用ＨＢＶＰＣＲ、ＨＣＶＲＴ－ＰＣＲ和ＨＥＶＲＴ－ＰＣＲ分别检测血清学标志阴性的非甲～戊型肝炎患者血清，并对其部分阳性产物进行克隆测序。结果８７例非甲～戊型肝炎血清ＨＢＶＤＮＡ均为阴性，９例（１０．３％）为ＨＣＶＲＮＡ阳性，部分经测序证实为ＨＣＶ１ｂ亚型；余７８例为ＨＢＶＤＮＡ和ＨＣＶＲＮＡ均阴性。该７８例中，１４例因无血清未作ＨＥＶＲＮＡ检测，余６４例中４９例（７６．６％）为ＨＥＶＲＮＡ阴性，１５例（２３．４％）为ＨＥＶＲＮＡ阳性。经序列分析显示，其中９例为典型的中国ＨＥＶ株基因序列，６例变异较大，与典型的中国株基因序列的同源性仅为８０％左右。４９例ＨＢＶＤＮＡ、ＨＣＶＲＮＡ和ＨＥＶＲＮＡ均阴性的血清中１６例（３２．６％）ＨＧＶＲＮＡ阳性。由此可见，该８７例中至少有９例为ＨＣＶ感染，１５例为ＨＥＶ感染，１６例为ＨＧＶ感染。结论对血清学标志阴性的非甲～戊型肝炎的病人应该用ＰＣＲ法进行病原学分型，以明确其诊断     

Implantable cardioverter-defibrillators improve survival after coronary artery bypass grafting in patients with severely impaired left ventricular function

Objective  

Patients with severe left ventricular (LV) dysfunction have a poor long term survival despite complete surgical revascularization. Recent data suggests that the use of Implantable Cardioverter-Defibrillator (ICD) improves survival in patients with severe LV dysfunction. We compared the survival impact of ICD implantation in patients with severe LV dysfunction who underwent CABG.     

Valuation of life: a concept and a scale

OBJECTIVES. The objective was to derive and test the psychometric characteristics of a scale to measure Valuation of Life (VOL). METHODS. Four samples were used in successive phases of exploratory factor analysis, confirmatory factor analysis, reliability and validity testing, and exploration of response-error effects. Estimates of Years of Desired Life were obtained under a variety of hypothetical quality-of-life (QOL)-compromising conditions of poor health. RESULTS. Confirmed 13-item (Positive VOL) and 6-item (Negative VOL) factors were obtained. A significant relationship between VOL and most Years of Desired Life estimates remained when demographic, health, quality of life, and mental health measures were controlled. Analysis of Negative VOL revealed that some respondents misunderstand the meaning of an agree response to negatively phrased items. DISCUSSION. VOL is a cognitive-affective schema whose function as a mediator and moderator between health and end-of-life decisions deserves further research.     

A high-resolution annotated physical map of the human chromosome 13q12-13 region containing the breast cancer susceptibility locus BRCA2.

Various types of physical mapping data were assembled by developing a set of computer programs (Integrated Mapping Package) to derive a detailed, annotated map of a 4-Mb region of human chromosome 13 that includes the BRCA2 locus. The final assembly consists of a yeast artificial chromosome (YAC) contig with 42 members spanning the 13q12-13 region and aligned contigs of 399 cosmids established by cross-hybridization between the cosmids, which were selected from a chromosome 13-specific cosmid library using inter-Alu PCR probes from the YACs. The end sequences of 60 cosmids spaced nearly evenly across the map were used to generate sequence-tagged sites (STSs), which were mapped to the YACs by PCR. A contig framework was generated by STS content mapping, and the map was assembled on this scaffold. Additional annotation was provided by 72 expressed sequences and 10 genetic markers that were positioned on the map by hybridization to cosmids.     

Eosinophilic cytoplasmic inclusions in fetal leukocytes: are Auer bodies a recapitulation of fetal morphology?

Among the most striking morphological features of acute nonlymphoblastic leukemias (ANLL) is the occurrence of eosinophilic cytoplasmic inclusions known as Auer rods on Auer bodies. We examined immature myeloid cells from the peripheral blood of 9 human fetuses of 16-19 wk gestation for the presence of such structures. Five of these 9 samples contained cytoplasmic inclusions, which were identical to the Auer rods typically seen in blast cells from patients with ANLL. The incidence of positive cells was low (1-5 cells/10,000 cells surveyed). The inclusions were azurophilic with Wright-Giemsa staining and were cytochemically positive with peroxidase, acid phosphatase, and Sudan black staining. We observed no inclusions in identically prepared control myeloid cells from the bone marrow of 5 patients with acute lymphoblastic leukemia in remission and 3 patients with chronic myelogenous leukemia in stable phase. Nor were they present in peripheral blood myeloid cells of 10 normal adults. Myeloid precursors in long-term bone marrow culture from 2 normal adult donors did not develop the inclusions during 24 hr of incubation with prostaglandin F2 (the abortifacient). These observations suggest that Auer rod formation is an occasional but normal phenomenon in fetal hematopoiesis.     

Dopamine beta-hydroxylase and plasma renin activity in patients with low-, normal-, and high-renin essential hypertension.

The relationship of serum dopamine-beta-hydroxylase (DBH), plasma renin activity (PRA) and urinary catecholamines (IU catechols) in various forms of essential hypertension (EHT) (low, normal and high renin) was evaluated. Eighty-four predominantly white, young (37 +/ 8 years (SD)), mildly hypertensive patients (diastolic pressure 93 +/- 4 mm Hg (SD)) continued their regular diet and received no medications. Thirteen patients had low-renin, 64 had normal-renin, and seven had high-renin EHT. DBH, total IU catechols and urinary norepinephrine were not different between these renin subgroups. DBH was significantly lower in all hypertensives (55.6 +/- 36 IU) and in the low-renin subgroup (46 +/- 30 IU) compared with normal subjects (68 +/- 35 IU) (p less than 0.01). However, the DBH range was so broad that an individual DBH value did not distinguish EHT from normals. After a baseline period, patients were randomly assigned to receive chlorthali done 50 mg q.a.m. or placebo in a double-blind study. In the chlorthalidone group 1 month after therapy, the diastolic pressure decreased, PRA increased, and total IU catechols and urinary norepinephrine increased. Serum DBH did not change during diuretic therapy. A significant correlation could not be shown between pretreatment DBH and the changes in PRA and IU catechols before and after diuretics for all treated EHT patients. However, within the normal PRA EHT subgroup receiving chlorthalidone, the one-third of patients with lowest pretreatment DBH levels (n = 10) were compared with the one-third of patients with the highest pretreatment DBH values (n = 10). The lower DBH patients showed significantly less change in PRA (delta PRA = 2.9 +/- 1.8 ng/ml/hr) compared with the higher DBH patients (delta PRA = 8.2 +/- 1.6; P less than 0.05). In some EHT patients, DBH levels may be related to PRA response to diuretic therapy.     

Autoantibody-associated cross-reactive idiotypes expressed at high frequency in chronic lymphocytic leukemia relative to B-cell lymphomas of follicular center cell origin

Using murine monoclonal antibodies (MoAbs) specific for immunoglobulin (Ig) cross-reactive idiotypes (CRI), we performed immunohistochemical analyses on frozen tissue sections and cytocentrifuge preparations of Ig-expressing malignant cells from patients with chronic lymphocytic leukemia (CLL) and B-cell non-Hodgkin's lymphomas (NHL) of follicular center cell origin. Twenty percent (4/20) of the Ig kappa light chain- expressing CLL cells reacted with 17.109, a MoAb against a major CRI on human IgM autoantibodies that is encoded by a conserved Ig variable- region gene (V gene) of the V kappa IIIb sub-subgroup. Another MoAb specific for V kappa IIIb framework determinant(s) reacted exclusively with all the 17.109-reactive CLL cells. Only one of 20 kappa light- chain-expressing CLL cells reacted with 6B6.6, a monoclonal antibody specific for a CRI commonly found on rheumatoid factor (RF) paraproteins with light-chain variable regions of the V kappa IIIa sub- subgroup. Finally, greater than 20% (8/34) of all CLL reacted with G6, a MoAb specific for an Ig heavy chain-associated CRI present on several RF paraproteins. In contrast, these CRIs were expressed at significantly lower frequencies in NHL of follicular center cell origin. Only one of 30 NHL expressing kappa light chains reacted with the 17.109 MoAb. Also, in contrast to the concordance between the 17.109-CRI and V kappa IIIb framework determinant(s) in CLL, two lymphomas in addition to the 17.109-reactive lymphoma were recognized by the anti-V kappa IIIb framework MoAb. None of the NHL reacted with either the 6B6.6 or the G6 MoAbs. These results are the first to demonstrate that CLL and NHL differ with respect to the expression of autoantibody-associated CRIs. The data support the notion that NHL of follicular center cell origin differs from CLL in its utilization and/or somatic mutation of Ig variable-region genes. The physiological and immunotherapeutic implications of these findings are discussed.     

Construction and characterization of a normalized cDNA library.

We have developed a simple procedure based on reassociation kinetics that can reduce effectively the high variation in abundance among the clones of a cDNA library that represent individual mRNA species. For this normalization, we used as a model system a library of human infant brain cDNAs that were cloned directionally into a phagemid vector and, thus, could be easily converted into single-stranded circles. After controlled primer extension to synthesize a short complementary strand on each circular template, melting and reannealing of the partial duplexes at relatively low C0t, and hydroxyapatite column chromatography, unreassociated circles were recovered from the flow through fraction and electroporated into bacteria, to propagate a normalized library without a requirement for subcloning steps. An evaluation of the extent of normalization has indicated that, from an extreme range of abundance of 4 orders of magnitude in the original library, the frequency of occurrence of any clone examined in the normalized library was brought within the narrow range of only 1 order of magnitude.     

Screening for alcohol abuse using CAGE scores and likelihood ratios

OBJECTIVE: To assess the performance of the CAGE (acronym referring to four questions, see below) questionnaire in discriminating between medicine outpatients with and without an alcohol abuse or dependence disorder. DESIGN: A cross-sectional design of a sample of consecutive patients who received both the alcohol module of the diagnostic interview schedule and the CAGE (Cut down, Annoyed, Guilty, Eye-opener) screening questionnaire. SETTING: The outpatient medical practice of an urban university teaching hospital. PATIENTS: All patients 18 years or older who signed a consent form approved by the university's institutional review board. MEASUREMENT: Calculation of the sensitivity, specificity, receiver operating characteristic (ROC) curve, and likelihood ratio for CAGE scores of 0 to 4. RESULTS: Thirty-six percent of the sample group met criteria for a history of alcohol abuse or dependence. A CAGE score of 2 or more was associated with a sensitivity and specificity of 74% and 91%. The calculated area under the ROC curve was 0.89, whereas the likelihood ratios for CAGE scores of 0 to 4 were 0.14, 1.5, 4.5, 13, and 100, respectively. These ratios were associated with posterior probabilities for an abuse or dependence disorder of 7%, 46%, 72%, 88%, and 98%, respectively. CONCLUSION: Clinicians can improve their ability to estimate a patient's risk for an alcohol abuse or dependence disorder using likelihood ratios for CAGE scores.     

c-tal, a helix-loop-helix protein, is juxtaposed to the T-cell receptor- beta chain gene by a reciprocal chromosomal translocation: t(1;7)(p32;q35)

Studies on nonrandom chromosomal translocations have been important for the identification of genes potentially involved in the malignant transformation of cells. The most widely studied translocations, involving members of the Ig supergene family, have shown juxtapositions of proto-oncogenes with the rearranging loci. Such translocations can inappropriately activate expression of the proto-oncogenes and thereby play a role in tumorigenesis. Because the cytogenetic analysis of a bone marrow sample from a child with T-cell acute lymphoblastic leukemia showed a (1;7)(p32;q35) translocation, we sought to determine if the translocation breakpoint was in the T-cell receptor (TCR)-beta gene locus on chromosome 7. Analysis of the TCR-beta gene by Southern blotting showed three rearranged bands. Nucleotide sequencing and Southern blot analysis of TCR-beta genomic clones, isolated from patient DNA, showed that one contained a normal rearrangement of the TCR-beta gene using V beta 12.2, D beta 2.1, and J beta 2.5, whereas two other clones contained DNA from derivative chromosomes 1 and 7. Chromosomal mapping showed that the (1;7) translocation breakpoint was 35 kb 3' to the c-tal gene locus. The juxtaposition of c-tal to the TCR- beta locus may enhance c-tal expression and contribute to T-cell leukemogenesis.