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61.
Rh incompatibility disease (ie Rh hemolytic disease of the fetus and newborn) has been implicated as a risk factor for schizophrenia. Here, we extend the maternal-fetal genotype incompatibility (MFG) test used in an earlier case-parent trio study that found significant evidence for an increased risk of schizophrenia in RHD MFG-incompatible children. We modify the MFG test for case-parent trios to include any number of siblings. This modified test enables us to use more of the available data from the earlier study. The increased sample size not only gives us greater power to test for MFG incompatibility but it also enables us to model the impact of previous RHD MFG-incompatible pregnancies on the relative risk of RHD MFG incompatibility in later-born siblings. This modeling is important, because RHD MFG incompatibility is a proxy for Rh incompatibility disease, and the risk of Rh incompatibility disease increases with the number of previous RHD MFG-incompatible pregnancies. The best-fitting models are consistent with the hypothesized effect that previous incompatible pregnancies increase the risk of schizophrenia due to RHD MFG incompatibility. There was significant evidence that the relative risk of schizophrenia in the second- and later-born RHD MFG-incompatible children is 1.7, consistent with earlier estimates. Our extension of the MFG test has general application to family-based studies of maternal-genotype and MFG interaction effects.  相似文献   
62.
The ability of bone cements to modify the apoptotic program in activated immune cells and the mechanisms by which they act were evaluated. Mononuclear cells were collected from healthy individuals, cultured for 4 and 24 h with phytohemoagglutinina-P and cement extracts and then tested to assess: (a) cell viability; (b) early apoptotic events, by Annexin V/propidium iodide staining; and (c) the expression of pro- (p53, c-myc, ICE) and anti-apoptotic (bcl-2) genes. After 4 h three cements were able to increase significantly the percentage of apoptotic cells, while after 24 h no differences were found. The proportion of dead cells was not significantly changed at either culture time. The simultaneous expression of both pro-apoptotic (ICE, c-myc, p53) and antiapoptotic genes (bcl-2) was investigated only with regard to the materials which induced significant changes in apoptosis: two cements induced the p53 expression, while the third down-regulated bcl-2. As apoptosis regulates the balance of immune response, the authors recommend that the interaction between materials and immune cells should be assessed, so that the use of pro-apoptotic materials may be avoided in patients with immune defects.  相似文献   
63.
The performance of two DNA line probe assays, a new version of INNO-LiPA Mycobacteria (Innogenetics, Ghent, Belgium) and the GenoType Mycobacterium (Hain Diagnostika, Nehren, Germany), were evaluated for identification of mycobacterial species isolated from liquid cultures. Both tests are based on a PCR technique and designed for simultaneous identification of different mycobacterial species by reverse hybridization and line probe technology. The INNO-LiPA Mycobacteria v2 targeting the 16S-23S rRNA gene spacer region was developed for the simultaneous identification of 16 different mycobacterial species. The GenoType Mycobacterium, which targets the 23S rRNA gene, allows simultaneous identification of 13 mycobacterial species. Both tests were evaluated on 110 mycobacterial strains belonging to 22 different mycobacterial species (20 reference strains, 83 clinical strains, and 4 Mycobacterium kansasii strains isolated from tap water) that were previously inoculated into MB/BacT bottles. The sensitivity of both methods, defined as the number of positive results obtained with the Mycobacterium genus probe together with an interpretable result on the number of samples tested was 110 of 110 (100%) for INNO-LiPA and 102 of 110 (92.7%) for GenoType. For samples with interpretable results, INNO-LiPA was able to correctly identify 109 of 110 samples (99.1%), whereas the GenoType correctly identified 100 of 102 samples (98.0%). Both tests were easy to perform, rapid, and reliable when applied to mycobacterial identification directly from MB/BacT bottles.  相似文献   
64.
The experimental dosimetry of a high dose rate (HDR) 192Ir source used for the brachytherapy of peripheral vessels is reported. The direct determination of the reference air kerma rate Kr agrees, within the experimental uncertainty, with the results obtained by a well ionization chamber calibrated at the NIST and the manufacturer's certification. A highly sensitive (HS) radiochromic film (RCF), that presents only one active layer, was used for the source dosimetry in a water phantom. The adopted experimental set-up, with the source in its catheter positioned on the RCF plane, seems to have given better accuracy of the RCF optical density measurements. The agreement between the measurement of the dose rate constant DKr (10 mm, pi/2) and the literature data confirmed the coherence of the HS RCF calibration obtained by the kerma in air measurements. The RCF measurements supplied dosimetric information about the dose to water per reference air kerma rate D(r, theta)/Kr along the source transverse bisector axis, the radial dose function g(r) and the anisotropy function F(r, theta). The value D(2 mm, pi/2)/Kr = 22.4 +/- 1.2 cGy h(-1)/(microGy h(-1)) is supplied with a dose uncertainty that is essentially due to the indeterminacy of the source position in the catheter. The data of the radial and anisotropy functions have been compared with Monte Carlo determinations reported in the literature.  相似文献   
65.
BACKGROUND: Although mixed states were classically described as various concomitant admixtures of depression and mania, the official current definitions in both DSM-IV and ICD-10 tend to restrict the concept to manic patients with full syndromal depression. Recent research has actually shown that mania with few depressive symptoms constitutes the most prevalent clinical presentation of mixed or dysphoric mania. Major depressive patients with few concomitant manic symptoms are not officially recognized within the current nosology. In this paper we attempt to delineate the clinical profile of such depressive mixed states in the context of bipolar I disorder. METHODS: In the Pisa day center, we studied 195 bipolar I patients who either met Pisa criteria for bipolar mixed state (n=159) or DSM-III-R criteria for major depressive episode (bipolar major depression or B-MD, n=36). Of the 159 patients identified by Pisa criteria as mixed state, 86 also met the criteria of the DSM-III-R for mixed episode (core mixed state or MS group), while 32 met the DSM III-R criteria for major depressive episode (provisionally defined as depressive mixed states, D-MS); the remaining patients (n=41, 25.7%) with predominatly manic picture were not included in the present comparisons. RESULTS: The three groups (B-MD, MS and D-MS) had close similarities in clinical and sociodemographic characteristics such as age, sex distribution, marital status, schooling, residence, age at onset, age of first treatment, age of first hospitalization, degree of chronicity of the index episode, stressor within the 6 months before the index episode, lifetime suicide attempts and premorbid temperament. First degree family history for bipolar illness and that for other mental disorders was also similar, except for major depression that was more common among the relatives of D-MS. MS and D-MS were further distinguished from B-MD by the fact that the latter followed a more 'cyclic' course with shorter yet greater number of episodes, and which began with a pure depressive episode; by contrast, MS and D-MS had fewer episodes of longer duration, less interepisodic remission, and tended to begin with a mixed episode. Incongruous psychotic features were more common in the two mixed groups compared to B-MD, and the most common features of the D-MS group were agitation, psychotic depression with irritable mood, pressured speech and/or flight of ideas. LIMITATION: It was not feasible to collect information blind to clinical status in patients with severe psychotic mood states. CONCLUSION: These data confirm the existence of psychotic agitated depressive mixed states with flight of ideas, distinct from cyclic retarded pure bipolar depressive states. The recognition of these affective states is clinically important to protect patients from the potentially harmful indiscriminate use of antidepressants and to provide them with the benefits of an anticonvulsant, a short-term neuroleptic, or ECT.  相似文献   
66.
B cell neoplasms present heterogeneous patterns of lymphoid organ involvement, which may be a result of the differential expression of chemokine receptors. We found that chemokine receptor (CCR)7, CXC chemokine receptor (CXCR)4, or CXCR5, the main chemokine receptors that mediate B cell entry into secondary lymphoid tissues and their homing to T cell and B cell zones therein, were highly expressed in B malignancies with widespread involvement of lymph nodes. Conversely, those pathologies with little or no nodular dissemination showed no expression to very low levels of CCR7 and CXCR5 and low to moderate levels of CXCR4. These findings provide evidence for the role of CCR7, CXCR4, and CXCR5 in determining the pattern of lymphoid organ involvement of B tumors. Functional studies were performed on B malignancies expressing different levels of CCR7, CXCR5, and CXCR4. Multiple myeloma (MM) cells did not express CCR7 nor CXCR5 and did not migrate in response to their ligands; a moderate expression of CXCR4 on MM cells was accompanied by a migratory response to its ligand, CXCL12. By contrast, cells from B cell chronic lymphocytic leukemia (B-CLL) expressed the highest levels of these chemokine receptors and efficiently migrated in response to all ligands of CCR7, CXCR4, and CXCR5. In addition, the migration index of B-CLL cells in response to both of the CCR7 ligands correlated with the presence of clinical lymphadenopathy, thus indicating that the high expression of functional chemokine receptors justifies the widespread character of B-CLL, representing a clinical target for the control of tumor cell dissemination.  相似文献   
67.
The current study describes the creation and validation of the Anger Cognitions Inventory (ACI) to assess the cognitive appraisals associated with resentful and reflective anger. The ACI was created based on a content analysis of self-reports of participants' thoughts and feelings following anger provocation in the laboratory. Exploratory and confirmatory factor analyses on two separate college student samples (N = 267 and N = 276, respectively) revealed five subscales which could validly be grouped into resentful and reflective anger. Convergent and divergent validity data showed that resentful anger correlated positively with anger-out/trait anger and reflective anger correlated positively with anger-in/brooding. A second study showed positive correlations between rumination and delayed cardiovascular recovery following anger provocation. Limitations of both studies include restricted samples which limit generalizability of results and cardiovascular recovery data collected in Study II which does not include assessment of autonomic balance between vagal and sympathetic responsivity.  相似文献   
68.
A new hybrid fixation stem, named cemented-locked uncemented (CLU), for total hip arthroplasty was developed to achieve good initial stability. Primary stability is guaranteed by the cement which is injected into two pockets in the lateral area. This leaves a large surface available for long-term biologic fixation (direct bone attachment on implant). This study evaluates in vitro the initial stability of the CLU prototype under torsional load, in comparison with cemented and cementless stems. The results show that the CLU stem is very stable in simulated stair climbing. Its micromotions are comparable to those of a cemented prosthesis, and significantly less (80-90% lower) than those for a cementless stem. These findings confirm the optimal initial stability expected from the CLU prototype. This new design, which employs hybrid fixation, should improve bone formation on the implant and reduce the risk of stem loosening.  相似文献   
69.
T cell subset alterations in idiopathic glomerulonephritis   总被引:1,自引:1,他引:1       下载免费PDF全文
Peripheral blood lymphocytes from 15 healthy controls and 59 patients with idiopathic glomerulonephritis were studied to determine whether an imbalance exists among human T cell subsets in these diseases. Twenty of the patients studied had a minimal change nephropathy (10 with nephrotic syndrome and 10 in sustained remission); 27 had a membranous glomerulonephritis (12 with nephrotic syndrome, six with isolated proteinuria and nine in complete remission); 12 patients had an IgA glomerulonephritis with heamaturia and mild proteinuria. Monoclonal antibodies directed at human T lymphocyte subsets termed OKT3, OKT4 and OKT8 were used in an indirect immunofluorescence assay in all cases. Patients with minimal change nephropathy, with or without nephrotic syndrome and patients with IgA glomerulonephritis showed mean values of OKT3+ cells (total peripheral T cells), helper OKT4+ cells, suppressor OKT8+ cells and OKT4+/OKT8+ cell ratio, in the normal range. Only the group of patients with membranous glomerulonephritis and nephrotic syndrome presented a mean OKT4+/OKT8+ ratio greater than the normal group (percentages: 2·43±0·3 vs 1·6±0·1 s.e.m.; P<0·02). This increased ratio was due to a reduction in the OKT8+ cell subset compared to the healthy subjects (percentages: 27·6±2·9 vs 36·8±1·4 s.e.m.; P<0·01). Our data shows that the functional lymphocyte disorders previously described in minimal change nephropathy and IgA glomerulonephritis are not due to a numerical imbalance of lymphocyte subsets. Such an imbalance of lymphocyte subsets was specifically observed in membranous glomerulonephritis with nephrotic syndrome. The true significance of this finding has to be clarified by longitudinal studies and functional tests.  相似文献   
70.
Many patients infected with HIV do not achieve or maintain virologic suppression below levels of detection while on potent combination antiretroviral therapy. The likelihood of emergence of incident mutations conferring reduced antiretroviral drug susceptibility was estimated among patients maintained on a stable regimen with ongoing detectable plasma HIV RNA levels. Ninety-eight HIV-infected patients were identified who had 2 genotypic antiretroviral resistance tests available. Poisson log-linear regression models were used to identify predictors and estimate incidence rates of number of acquired antiretroviral drug resistance mutations per person-year. At the 1st resistance test, 88% of patients had evidence of at least 1 mutation. Sixty percent of patients acquired at least 1 new mutation during a median of 9.3 months between consecutive resistance tests, with an incidence rate of 1.61 acquired mutations per person-year (95% CI: 1.36-1.90). Predictors of resistance evolution included average plasma HIV RNA level, HIV RNA slope, and number of mutations detected at the 1st resistance test. The likelihood of acquiring drug resistance mutations while remaining on potent combination antiretroviral therapy that does not confer complete suppression of HIV replication is relatively low and depends on the level of viral replication and prior resistance.  相似文献   
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