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61.
62.
Nilly Mor Paula Hertel Thuy Anh Ngo Tal Shachar Shimrit Redak 《Journal of behavior therapy and experimental psychiatry》2014
Background and objectives
Rumination, a maladaptive cognitive style of responding to negative mood, is thought to be maintained by a variety of cognitive biases. However, it is unknown whether rumination is characterized by interpretation biases.Methods
Two experiments examined the link between rumination and interpretation biases, revealed in lexical-decision tasks (LDT). A homograph with both benign and ruminative or otherwise negative meaning was presented on each trial and followed by a letter string, to which participants responded by judging whether it was a word or a non-word. Letter strings were non-words or words related or unrelated to one meaning of the homograph.Results
In both experiments, faster latencies to respond to targets related to the ruminative meaning of the homographs were produced by students with higher scores on self-report measures of rumination. Moreover, these biases were associated with both brooding, the maladaptive form of rumination, and reflection, the more adaptive component. No measure of rumination was significantly correlated with general biases toward negative meaning (Experiment 1) or with threatening interpretations of homographs (Experiment 2).Limitations
The paucity of available rumination-related homographs dictated the use of non-fully randomized stimuli presentation (Experiment 1) or the use of only one set of the meanings associated with the homographs (Experiment 2).Conclusions
Rumination is associated with a tendency to interpret ambiguous information in a rumination-consistent manner. This tendency may exacerbate ruminative thinking and can possibly be a target for future intervention. 相似文献63.
Shemesh S Kamari Y Shaish A Olteanu S Kandel-Kfir M Almog T Grosskopf I Apte RN Harats D 《Atherosclerosis》2012,220(2):329-336
ObjectiveRecent studies indicate that regulatory T cells (Tregs) attenuate murine atherosclerosis. Since interleukin (IL)-2 induces Tregs proliferation, we tested the impact of L19-IL2, a fusion antibody specific to extra-domain B of fibronectin (ED-B) containing an active human IL-2 molecule, in experimental atherosclerosis.Methods and resultsL19-IL2 or appropriate controls were given intravenously to 6 month old Western diet-fed apoE?/? mice on day 1, 3, and 5. Human IL-2 was detected on day 7 within atherosclerotic plaques of L19-IL2-treated mice, and magnetic resonance imaging of the plaques showed a significant adventitial gadolinium enhancement on day 7 and 13, suggesting microvascular leakage as a result of the pharmacodynamic activity of L19-IL2. Treatment with L19-IL2 significantly reduced the size of pre-established atherosclerotic plaques at the thoracic aorta (Sudan III stained area) and in the aortic root area (microscopic, morphometric analysis) on day 7 as compared to controls (L19, D1.3-IL2, NaCl) as well as compared to baseline (day 0). Tregs markers Foxp3 and CTLA4 were highly increased in plaques after L19-IL2 treatment compared to controls (p < 0.01), whereas the macrophage marker Mac3 was significantly reduced (p < 0.03). Co-treatment with IL-2-receptor blocking antibody PC61 abrogated L19-IL2-induced plaque reduction compared with IgG control (p < 0.03).ConclusionL19-IL2 delivers functional IL-2 to pre-established atherosclerotic plaques of WD-fed apoE?/? mice resulting in significant plaque size reduction mediated by local Tregs. 相似文献
64.
Willingham SB Volkmer JP Gentles AJ Sahoo D Dalerba P Mitra SS Wang J Contreras-Trujillo H Martin R Cohen JD Lovelace P Scheeren FA Chao MP Weiskopf K Tang C Volkmer AK Naik TJ Storm TA Mosley AR Edris B Schmid SM Sun CK Chua MS Murillo O Rajendran P Cha AC Chin RK Kim D Adorno M Raveh T Tseng D Jaiswal S Enger PØ Steinberg GK Li G So SK Majeti R Harsh GR van de Rijn M Teng NN Sunwoo JB Alizadeh AA Clarke MF Weissman IL 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(17):6662-6667
CD47, a "don't eat me" signal for phagocytic cells, is expressed on the surface of all human solid tumor cells. Analysis of patient tumor and matched adjacent normal (nontumor) tissue revealed that CD47 is overexpressed on cancer cells. CD47 mRNA expression levels correlated with a decreased probability of survival for multiple types of cancer. CD47 is a ligand for SIRPα, a protein expressed on macrophages and dendritic cells. In vitro, blockade of CD47 signaling using targeted monoclonal antibodies enabled macrophage phagocytosis of tumor cells that were otherwise protected. Administration of anti-CD47 antibodies inhibited tumor growth in orthotopic immunodeficient mouse xenotransplantation models established with patient tumor cells and increased the survival of the mice over time. Anti-CD47 antibody therapy initiated on larger tumors inhibited tumor growth and prevented or treated metastasis, but initiation of the therapy on smaller tumors was potentially curative. The safety and efficacy of targeting CD47 was further tested and validated in immune competent hosts using an orthotopic mouse breast cancer model. These results suggest all human solid tumor cells require CD47 expression to suppress phagocytic innate immune surveillance and elimination. These data, taken together with similar findings with other human neoplasms, show that CD47 is a commonly expressed molecule on all cancers, its function to block phagocytosis is known, and blockade of its function leads to tumor cell phagocytosis and elimination. CD47 is therefore a validated target for cancer therapies. 相似文献
65.
Shijulal Nelson-Sathi Tal Dagan Giddy Landan Arnold Janssen Mike Steel James O. McInerney Uwe Deppenmeier William F. Martin 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(50):20537-20542
Archaebacterial halophiles (Haloarchaea) are oxygen-respiring heterotrophs that derive from methanogens—strictly anaerobic, hydrogen-dependent autotrophs. Haloarchaeal genomes are known to have acquired, via lateral gene transfer (LGT), several genes from eubacteria, but it is yet unknown how many genes the Haloarchaea acquired in total and, more importantly, whether independent haloarchaeal lineages acquired their genes in parallel, or as a single acquisition at the origin of the group. Here we have studied 10 haloarchaeal and 1,143 reference genomes and have identified 1,089 haloarchaeal gene families that were acquired by a methanogenic recipient from eubacteria. The data suggest that these genes were acquired in the haloarchaeal common ancestor, not in parallel in independent haloarchaeal lineages, nor in the common ancestor of haloarchaeans and methanosarcinales. The 1,089 acquisitions include genes for catabolic carbon metabolism, membrane transporters, menaquinone biosynthesis, and complexes I–IV of the eubacterial respiratory chain that functions in the haloarchaeal membrane consisting of diphytanyl isoprene ether lipids. LGT on a massive scale transformed a strictly anaerobic, chemolithoautotrophic methanogen into the heterotrophic, oxygen-respiring, and bacteriorhodopsin-photosynthetic haloarchaeal common ancestor.Halophilic archaebacteria (Haloarchaea) require concentrated salt solutions for survival and can inhabit saturated brine environments such as salt lakes, the Dead Sea, and salterns (1). In rRNA and phylogenomic analyses of informational genes, Haloarchaea always branch well within the methanogens (2–4). Haloarchaea can thus be seen as deriving from methanogen ancestors, but the physiology of methanogens and halophiles could hardly be more different. Methanogens are strict anaerobes, most species are lithoautotrophs that use electrons from H2 to reduce CO2 to methane (obligate hydrogenotrophic methanogens), thereby generating a chemiosmotic ion gradient for ATP synthesis in their energy metabolism, although some species can generate methane from reduced C1 compounds, or acetate in the case of aceticlastic forms (5–7). Their carbon metabolism involves the Wood–Ljungdahl (acetyl-CoA) pathway of CO2 fixation (5–7). In contrast, Haloarchaea are obligate heterotrophs that typically use O2 as the terminal acceptor of their electron transport chain, although many can also use alternative electron acceptors such as nitrate in addition to light harnessing via a bacteriorhodopsin-based proton pumping system (8). The evolutionary nature of that radical physiological transformation from anaerobic chemolithoautotroph to aerobic heterotroph is of interest.Many individual reports document that lateral gene transfer (LGT) from eubacteria was involved in the origin of at least some components of haloarchaeal metabolism. These include the operon for gas vesicle formation, which allows Haloarchaea to remain in surface waters (9), the newly identified methylaspartate cycle of acetyl-CoA oxidation (10), various components of the haloarchaeal aerobic respiratory chain (11–18), and proteins involved in the assembly of FeS clusters (19). The sequencing of the first haloarchaeal genome over a decade ago identified some eubacterial genes that possibly could have been acquired by lateral gene transfer (11, 20), and whereas substantial data that would illuminate the origin of haloarchaeal physiology have accumulated since then, those data have not been subjected to comparative evolutionary analysis. Investigating the role of the environment in haloarchaeal genome evolution, Rhodes et al. (21) recently showed that Haloarchaea are indeed far more likely to acquire genes from other halophiles, but they did not address the issues at the focus of our present investigation, namely: How many eubacterial acquisitions are present in haloarchaeal genomes? How was the physiological transformation of methanogens to Haloarchaea affected by LGT? Do those acquisitions trace to the haloarchaeal common ancestor as a single acquisition or not?To discern whether the eubacterial genes in haloarchaeal genomes are the result of multiple independent transfers in individual lineages or the result of a single ancient mass acquisition, here we have analyzed 10 sequenced haloarchaeal genomes—Haloarcula marismortui (22), Halobacterium salinarum (23), Halobacterium sp. (20), Halomicrobium mukohataei (24), Haloquadratum walsbyi (25), Halorhabdus utahensis (26), Halorubrum lacusprofundi (27), Natrialba magadii (28), Natronomonas pharaonis (29), and Haloterrigena turkmmenica (30)—in the context of 65 other archaebacterial and >1,000 eubacterial reference genomes. 相似文献
66.
67.
Recent studies suggest an increased risk for Pneumocystis jirovecii pneumonia (PJP) in adults receiving short-interval rituximab-CHOP (cyclophosphamide, doxorubicin, vincristine and prednisone) therapy for diffuse large cell B cell lymphoma (DLBCL). This retrospective study evaluates precise PJP incidence and the efficacy of anti-PJP prophylaxis in DLBCL. Patients with DLBCL, aged ≥18 years and treated between December 2004 and December 2010, were included. Details of treatment-related respiratory infections, focusing on PJP incidence, risk factors and prophylaxis, were assessed. A total of 132 patients were analyzed; 47 were treated with rituximab-CHOP therapy every 21 days (R-CHOP-21) and 85 were treated every 14 days (R-CHOP-14). The incidence of treatment-related respiratory infections was higher in patients receiving R-CHOP-14. PJP was diagnosed in 5 patients: 4 in the R-CHOP-14 (6.6%) and 1 in the R-CHOP-21 cohort (2.6%), using triplex polymerase chain reaction (PCR) for PJ in bronchoalveolar fluid. None of the patients receiving P.jirovecii prophylaxis (n = 33) developed PJP, compared with 6.6% of those treated with R-CHOP-14 without such prophylaxis. An older age and R-CHOP administered every 14 rather than every 21 days increased the PJP risk. Trimethoprim/sulfamethoxazole prophylaxis is found to be highly efficient in preventing this life-threatening complication and, therefore, should be recommended for patients receiving the R-CHOP-14 regimen. 相似文献
68.
69.
T Zuckerman T Katz N Haddad R Fineman EJ Dann I Avivi Y Ofran I Gavish T Faibish D Sahar E Hertz E Sabo Y Reisner JM Rowe 《American journal of hematology》2012,87(9):875-879
The use of allogeneic stem cell transplantation (SCT) for chronic myeloid leukemia (CML) was almost abandoned in recent years for very effective targeted therapy with tyrosine kinase inhibitors (TKIs). However, approximately one third of patients still need another treatment including SCT. 38 consecutive CML patients were treated (most in preimatinib era) with allogeneic SCT, using partial T cell depletion (TCD) and preemptive donor lymphocyte infusion (DLI), without post‐transplant graft‐versus‐host disease (GvHD) prophylaxis. Conditioning included busulfan, cyclophosphamide, antithymocytic globulin, and fludarabine followed by donor stem cell transfusion. With a median follow up of 90.5 months (1–134), 32 patients are alive. 97% engrafted. 5‐year leukemia free survival (LFS) and overall survival (OS) were 78.95% and 84.2%, respectively. All patients are in major molecular remission and 78% in complete molecular remission. Transplant‐related mortality (TRM) was 13%. Twenty‐four patients received DLI for residual disease. Acute GvHD, mostly Grades I‐II, occurred in 18% of patients post‐transplant and in 24% of patients receiving DLI. In conclusion, the risk‐adapted approach using only partial TCD and preemptive escalated dose of DLI precluded the need for immunosuppressive medications and reduced the risk of significant GvHD without compromising engraftment and long‐term disease control. Am. J. Hematol. 2012. © 2012 Wiley Periodicals, Inc. 相似文献
70.
Dror Tal Dov Hershkovitz Gil Kaminski-Graif Guy Wiener Orit Samuel Avi Shupak 《Clinical neurophysiology》2013,124(12):2445-2449