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41.
The aim of the present study was, first, to evaluate the prognostic value of mid-regional proadrenomedullin (proADM) in emergency department (ED) patients with a diagnosis of community acquired pneumonia (CAP) and, second, to analyze the added value of proADM as a risk stratification tool in comparison with other biomarkers and clinical severity scores.  相似文献   
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Waldenstrom macroglobulinemia (WM) is an incurable low-grade lymphoma characterized by bone marrow (BM) involvement of IgM secreting lymphoplasmacytic cells. The induction of unfolded protein response (UPR) genes ("physiologic" UPR) enables cells to differentiate into professional secretory cells capable of production of high amounts of endoplasmic reticulum (ER)-processed proteins, such as immunoglobulins. Ultimately, the initially cytoprotective UPR triggers an apoptotic cascade if ER stress is not corrected, called proapoptotic/terminal UPR. We show that WM cells inherently express the physiologic UPR machinery compared with normal BM cells, and that increased ER stress leads to proapoptotic/terminal UPR in WM cells. We therefore examined tunicamycin, ER stress inducer, for potential antitumor effects in WM. Tunicamycin induced significant cytotoxicity, apoptosis and cell-cycle arrest, and inhibited DNA synthesis in WM cell lines and primary BM CD19(+) cells from patients with WM with an inhibitory concentration (IC(50)) of 0.5 microg/mL to 1 microg/mL, but not in healthy donor cells. Importantly, coculture of WM cells in the context of the BM microenvironment did not inhibit tunicamycin-induced cytotoxicity. Finally, we demonstrate that ER stress inducer synergizes with other agents used in the treatment of WM. These preclinical studies provide a framework for further evaluation of ER stress inducing agents as therapeutic agents in WM.  相似文献   
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IntroductionIt has been hypothesized that lifelong premature ejaculation is part of a biological variation in the intravaginal ejaculation latency, but what causes this variation remains poorly understood.AimThe aim of this study is to elucidate whether variations in ejaculation latencies in an experimental rat model for premature ejaculation are linked to differences in the spinal command of ejaculation.Main Outcome MeasuresElectrical microstimulation of the spinal generator for ejaculation revealed an accelerated expulsion phase in rapid ejaculating rats.MethodsAdult male Wistar rats were categorized as “sluggish,”“normal,” or “rapid” ejaculators on the basis of their ejaculation frequency in sexual mating tests. One to three weeks after selection, males were urethane anesthetized and electrically microstimulated in the spinal generator for ejaculation, evoking ejaculation. Bulbospongiosus muscle electromyographic and intraluminal vas deferens pressure were measured simultaneously, representing, respectively, the expulsion and emission phase in ejaculation.ResultsElectrical microstimulation of the spinal generator for ejaculation evoked ejaculation in “sluggish” (N = 9), “normal” (N = 13), and “rapid” (N = 11) ejaculating rats. Vas deferens contraction (emission phase) was evoked at different stimulation strengths, but response properties were not statistically different between “sluggish,”“normal,” and “rapid” ejaculator rats. Bulbospongiosus muscle contractions (expulsion phase) following microstimulation was significantly accelerated in “rapid” rats as compared with “sluggish” and “normal” rats. The total duration of bulbospongiosus muscle contractions remained unchanged between the three ejaculator groups.ConclusionsOur results provide the first scientific evidence supporting a neurophysiological difference between “rapid,”“normal,” and “sluggish” ejaculators, expressed as an accelerated expulsion phase in “rapid” ejaculator rats. This bridges the gap between a sexual behavior trait and the spinal command of ejaculation. Borgdorff A, Rössler A-S, Clément P, Bernabé J, Alexandre L, and Giuliano F. Differences in the spinal command of ejaculation in rapid ejaculating rats. J Sex Med 2009;6:2197–2205.  相似文献   
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Background This study assessed the effectiveness of computerized measurement and feedback of health-related quality of life (HRQoL) in daily clinical practice in patients with chronic liver disease. Methods One hundred and sixty-two patients (61% men; mean age 47.5 years) regularly completed computerized HRQoL questionnaires before each consultation for the duration of 1 year. Six physicians were randomly assigned to the experimental group and received an instant online graphical output of data. Five other physicians were randomly assigned to the control group and conducted their consultations as usual. Differences between groups on generic- and disease-specific HRQoL, patient management, and patient satisfaction with the consultation were assessed, as were physicians’ experiences with HRQoL data and effects on their consultations. Results No direct effect of the experimental condition on patients’ HRQoL was found. However, an interaction effect of the experimental condition and age was found: older patients in the experimental group had significantly better disease-specific HRQoL (F = 4.16; P = 0.04) and generic mental HRQoL (F = 4.62; P = 0.03) than patients in the control group. Also, male patients in the experimental group had better generic mental HRQoL than patients in the control group (F = 6.10; P = 0.02). Physicians in the experimental group altered their treatment policy significantly more often than did physicians in the control group (z = −3.73, P = 0.00), and their experiences with the availability of HRQoL information were generally positive. The scores on patient satisfaction with the consultation did not differ significantly between the experimental and control groups (z = −1.20, P = 0.23). Conclusions Computerized measurement and feedback of HRQoL in a daily clinical practice of an outpatient department of hepatology did not improve HRQoL for the entire group of chronic liver patients but, rather, improved disease-specific HRQoL of older patients with chronic liver disease and mental HRQoL of older patients and male patients with chronic liver disease. It also had an effect on patient management.  相似文献   
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To further clarify the cognitive syndrome in subcortical vascular dementia (VaD), we investigated 20 patients with early-stage VaD as compared with 30 patients with Alzheimer's disease (AD) and 22 normal controls using episodic memory, attention/executive function and language tests. The patient groups were closely matched in terms of age, education and severity of dementia. The VaD patients had a significantly better free recall, cued recall and recognition memory than AD patients, the recognition being within normal limits in VaD. In addition, VaD patients had a greater number of perseverative errors during the Modified Card Sorting test, while AD patients exhibited more perseverations of semantic fluency. The results of retrieval deficit syndrome and increased number of perseverations during tasks sensitive to frontal lobe function are in agreement with the studies emphasizing the importance of frontal dysfunction in subcortical VaD. These findings are relevant for the early diagnosis of VaD and might be useful in the differential diagnosis with AD.  相似文献   
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Peptides corresponding to the BH3 domains of Bax (BaxBH3) or Bcl-2 (Bcl2BH3) are potent inducers of apoptosis when fused to the Atennapedia plasma membrane translocation domain (Ant). BaxBH3Ant and Bcl2BH3Ant caused a mitochondrial membrane permeabilization (MMP) and apoptosis, via a mechanism that was not inhibited by overexpressed Bcl-2 or Bcl-X(L), yet partially inhibited by cyclosporin A (CsA), an inhibitor of the mitochondrial permeability transition pore. When added to isolated mitochondria, BaxBH3 and Bcl2BH3 induced MMP, which was inhibited by CsA. However, Bcl-2 or Bcl-X(L) failed to inhibit MMP induced by BaxBH3 and Bc2BH3 in vitro, while they efficiently suppressed the induction of MMP by the Vpr protein (from human immunodeficiency virus-1), a ligand of the adenine nucleotide translocator (ANT). BaxBH3 but not Bcl2BH3 was found to interact with ANT, and only BaxBH3 (not Bcl2BH3) permeabilized ANT proteoliposomes and induced ANT to form non-specific channels in electrophysiological experiments. In contrast, both BaxBH3 and Bcl2BH3 were able to stimulate channel formation by recombinant Bax protein. Thus, BaxBH3 might induce MMP via an action on at least two targets, ANT and Bax-like proteins. In contrast, Bcl2BH3 would elicit MMP in an ANT-independent fashion. In purified mitochondria, two ligands of ANT, bongkrekic acid and the protein vMIA from cytomegalovirus, failed to prevent MMP induced by BaxBH3 or Bcl2BH3. In conclusion, BaxBH3 and Bcl2BH3 induce MMP and apoptosis through a mechanism which overcomes cytoprotection by Bcl-2 and Bcl-X(L).  相似文献   
48.
Focal nodular hyperplasia inducing hepatic vein obstruction   总被引:3,自引:0,他引:3  
OBJECTIVE: The records of 10 patients with focal nodular hyperplasia inducing intrahepatic vein obstruction were reviewed. The purpose of this study was to describe and emphasize the imaging features of these findings. CONCLUSION: Focal nodular hyperplasia may be responsible for hepatic vein obstruction with hepatic vein collaterals. The relatively large size and central location of the lesions seem to play important roles in the obstruction of the hepatic veins.  相似文献   
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Chronic lymphocytic leukemia follows an extremely variable clinical course with survival range from months to decades. Some patients present minimal symptoms and others organomegaly requiring rapidly therapy. Therapeutic options take into account efficacy, toxicity and prognostic factors. One of the well known prognosis factor is the clinical staging developed either by Rai et al. or by Binet et al. However, there is an important heterogeneity concerning the course of the disease among patients within a single stage group. Recently, several important observations related to the biologic significance of VH gene mutational status, expression of CD38, over-expression of ZAP-70 and chromosomal aberrations have led to the ability to identify high risk patients with rapid disease progression and lower survival. It has been demonstrated that the VH mutation status is clinically highly relevant. CLL patients with unmutated VH gene show an unfavourable course with a very rapid progression. Specific genomic aberrations have been associated with disease characteristics such as lymphadenopathy related to 11q deletion and resistance to treatment related to 17p deletion. VH gene mutation status and genomic aberrations appear separate parameters when considering their prognostic relevance but nevertheless they are correlated: unfavourable aberrations (11q- and 17p-) occur more frequently in VH unmutated CLL patients. According to these prognostic factors, several treatments including purine analogues and/or monoclonal antibodies have been tested with different schedules and doses of monoclonal antibodies (rituximab and alemtuzumab) considering safety to determine the better efficacy. Infections and haemolytic anemia remain the most frequent complications during conventional chemotherapy. In autologous transplant setting, the transplant related mortality is less than 10%, but survival curve do not show a plateau with about 50% of patients relapsing at 4 years. Conventional allogeneic transplantation could achieve durable remission and probably cure the disease but at the price of a too high transplant related mortality related to depressive immune status and old age of CLL population. In order to minimize the toxicity and to improve graft-versus-leukemia effect, development of reduced intensity conditioning (RIC) regimens appear particularly important for CLL patients. Recent studies, although a still short follow-up show very promising results and use of monoclonal antibodies in the conditioning or just after transplant could improve the results of allogeneic stem cell transplantation and cure a larger number of CLL patients. Recent advances to categorize CLL patients according to risk stratification regarding new prognostic factors (FISH, CD38, ZAP70, Ig mutational status) should allow to define better the best therapeutic strategy. In parallel, age, co morbidities and the notion of the risk-adapted strategy have also an important impact adding.  相似文献   
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