The energy-transducing NADH: quinone (Q) oxidoreductase (complex I) is the largest and most complicated enzyme complex in the oxidative phosphorylation system. Complex I is a redox pump that uses the ...redox energy to translocate H
+ (or Na
+) ions across the membrane, resulting in a significant contribution to energy production. The need to elucidate the molecular mechanisms of complex I has greatly increased. Many devastating neurodegenerative disorders have been associated with complex I deficiency. The structural and functional complexities of complex I have already been established. However, intricate biogenesis and activity regulation functions of complex I have just been identified. Based upon these recent developments, it is apparent that complex I research is entering a new era. The advancement of our knowledge of the molecular mechanism of complex I will not only surface from bioenergetics, but also from many other fields as well, including medicine. This review summarizes the current status of our understanding of complex I and sheds light on new theories and the future direction of complex I studies.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Complete elucidation of the phase behavior of phospholipid bilayers requires information on the subtransition from the lamellar crystal (Lc) phase to the gel phase. However, for bilayers of saturated ...diacylphosphatidylcholines (CnPCs), especially longer chain homologs, equilibration in the Lc phase is known to be very slow. In this study, bilayer phase transitions of three CnPCs with longer acyl chains, C19PC, C20PC and C21PC, were observed by differential scanning calorimetry under atmospheric pressure and by light-transmittance measurements under high pressure. Using lipid samples treated by thermal annealing enabled the observation of the sub-, pre- and main transitions of the C19PC and C20PC bilayers under atmospheric pressure. Only the pre- and main transitions could be observed for the C21PC bilayer due to very slow kinetics of the Lc phase formation for lipids with long acyl chains. The temperature and pressure phase diagrams constructed and phase-transitions quantities (enthalpy, entropy and volume changes) evaluated for these bilayers were compared with one another and with those of bilayers of the CnPC homologs examined in previous studies. These results allowed us (1) to clarify the temperature- and pressure-dependent phase sequence and phase stability of the CnPC (n=12-22) bilayers as a function of the hydrophobicity of the molecules, (2) to prove the presence of a shorter and a longer limit (n=13 and 21) in the acyl chain length for the pressure-induced bilayer interdigitation and (3) to reveal the chain-length dependence of the thermodynamic quantities of the subtransitions including the volume change.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Double-stranded RNA (dsRNA) is produced upon viral infection and can activate innate immunity. Polyinosinic:polycytidylic acids poly(I:C) is a synthetic mimetic of dsRNA and functions through an ...endosomal receptor, Toll-like receptor (TLR) 3 or cytosolic receptors. Another type of dsRNA, polyadenylic:polyuridylic acids poly(A:U), can also act as an immune adjuvant, but it remains unclear how it exhibits its adjuvant effects. Here, we have characterized the adjuvant effects of poly(A:U). Poly(A:U) could induce both IFN-α and IL-12p40 from murine bone marrow dendritic cells (DCs). Poly(A:U)-induced IFN-α production depended on a DC subset, plasmacytoid dendritic cell (pDC), and required TLR7. IL-12p40 was also produced by poly(A:U)-stimulated pDC in a TLR7-dependent manner. In addition to pDC, conventional dendritic cell (cDC) also produced IL-12p40 in response to poly(A:U). This IL-12p40 induction resulted from two cDC subsets, CD24high cDC and CD11bhigh cDC in a TLR3- and TLR7-dependent manner, respectively. In vivo injection of poly(A:U) with antigen led to clonal expansion of and IFN-γ production from antigen-specific CD8+ T cells. Consistent with the in vitro findings, TLR3 and TLR7 were required for the clonal T-cell expansion. Notably, TLR3, rather than TLR7, was critical for generating IFN-γ-producing CD8+ T cells. CD8+ T-cell responses induced by poly(A:U) were independent of type I IFN signaling. Our results demonstrate that poly(A:U) functions as an in vivo immunoadjuvant mainly through TLR3 and TLR7.
Type-II NADH-menaquinone oxidoreductase (NDH-2) is an essential respiratory enzyme of the pathogenic bacterium Mycobacterium tuberculosis (Mtb) that plays a pivotal role in its growth. In the present ...study, we expressed and purified highly active Mtb NDH-2 using a Mycobacterium smegmatis expression system, and the steady-state kinetics and inhibitory actions of phenothiazines were characterized. Purified NDH-2 contains a non-covalently bound flavin adenine dinucleotide cofactor and oxidizes NADH with quinones but does not react with either NADPH or oxygen. Ubiquinone-2 (Q2) and decylubiquinone showed high electron-accepting activity, and the steady-state kinetics and the NADH-Q2 oxidoreductase reaction were found to operate by a ping-pong reaction mechanism. Phenothiazine analogues, trifluoperazine, Compound 1, and Compound 2 inhibit the NADH-Q2 reductase activity with IC50 = 12, 11, and 13 μm, respectively. Trifluoperazine inhibition is non-competitive for NADH, whereas the inhibition kinetics is found to be uncompetitive in terms of Q2.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Central nervous system (CNS) events, including CNS relapse and progression to CNS, are known to be serious complications in the clinical course of patients with lymphoma. This study aimed to evaluate ...the risk of CNS events in patients with diffuse large B‐cell lymphoma in the rituximab era. We performed a retrospective survey of Japanese patients diagnosed with diffuse large B‐cell lymphoma who underwent primary therapy with R‐CHOP chemoimmunotherapy between September 2003 and December 2006. Patients who had received any prophylactic CNS treatment were excluded. Clinical data from 1221 patients were collected from 47 institutions. The median age of patients was 64 years (range, 15–91 years). We noted 82 CNS events (6.7%) and the cumulative 5‐year probability of CNS events was 8.4%. Patients with a CNS event demonstrated significantly worse overall survival (P < 0.001). The 2‐year overall survival rate after a CNS event was 27.1%. In a multivariate analysis, involvement of breast (relative risk RR 10.5), adrenal gland (RR 4.6) and bone (RR 2.0) were identified as independent risk factors for CNS events. We conclude that patients with these risk factors, in addition to patients with testicular involvement in whom CNS prophylaxis has been already justified, are at high risk for CNS events in the rituximab era. The efficacy and manner of CNS prophylaxis in patients for each involvement site should be evaluated further. (Cancer Sci 2012; 103: 245–251)
Full text
Available for:
BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
In very-elderly diffuse large B-cell lymphoma (DLBCL) patients, treatment intensities must be lowered due to the risks of comorbidities and organ function deterioration, and treatment outcomes are ...worse compared to younger patients. Very-elderly patients are often excluded from DLBCL clinical trials, and optimal treatments and dosages are not established. In this clinical trial, we examined the efficacy and safety of 6 courses of R-mini CHP therapy (cf., CHOP cyclophosphamide, doxorubicin, vincristine, and prednisone) in which vincristine is omitted to avoid the peripheral neuropathy that reduces elderly patients' quality of life, as remission induction therapy in DLBCL patients aged≥80 years.
Clinical information regarding non-Hodgkin lymphoma (NHL) in adolescents and young adults (AYA) is lacking. We retrospectively analyzed 1426 consecutively registered patients with newly diagnosed ...NHL. Of 798 DLBCL patients, 42 (5.3%) were identified as AYA (16–39 years). The characteristics of AYA DLBCL patients showed no significant differences compared to older adult DLBCL patients (age ≥ 40 years). Progression-free survival (PFS) and overall survival (OS) in AYA were similar to those in patients aged 40–60 years. However, in older adult groups, PFS and OS were significantly different according to the age group (40–60, 61–79, and ≥ 80 years). In univariate analysis in AYA, performance status, clinical stage, International Prognostic Index (IPI), and age-adjusted IPI significantly affected both PFS and OS. In multivariate analysis, only clinical stage was identified as an independent predictor among AYA. In conclusion, disease characteristics and outcomes of DLBCL in AYA were nearly the same as those in older adults.
Full text
Available for:
EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Central nervous system (CNS) involvement is a serious complication in patients with diffuse large B-cell lymphoma (DLBCL) and evaluating CNS risk is an important issue. Using the standard ...international prognostic index (IPI) and CNS-IPI, a recently proposed model including IPI risk factors and adrenal/kidney involvement, we assessed CNS risk in 1220 untreated DLBCL patients who received R-CHOP without prophylaxis. According to the standard IPI, the cumulative incidences of CNS involvement at 2 years were 1.3, 4.6, 8.8, and 12.7% in the low-, low-intermediate-, high-intermediate-, and high-risk groups, respectively (p <.001). This result is comparable with that of the CNS-IPI. Patients with breast involvement tended to have lower risk according to the standard IPI but showed frequent CNS involvement, similar to patients with testis involvement. The standard IPI is also a useful predictor of CNS involvement. Patients with breast/testis involvement would be candidates for prophylaxis regardless of the standard IPI risk.
Full text
Available for:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Primary immune thrombocytopenia (ITP) is an autoimmune disease mediated by the production of auto-antibody against platelets. Rituximab, an anti-CD20 antibody, is reported to be useful for treatment ...of ITP. In Japan, however, robust evidence on this treatment has not been accumulated. Hence, we conducted this open-label phase III clinical trial to confirm the efficacy and safety of rituximab, administered at 375 mg/m
2
once per week at weekly intervals for 4 consecutive weeks in Japanese patients with chronic ITP, who had relapsed and were refractory to conventional therapy. The primary endpoint was defined as the percentage of patients with a platelet count above 50 × 10
9
/L at week 24 after the first dose of rituximab, which was 30.8 % of 26 patients (95 % confidence interval 14.3–51.8 %). Although the lower confidence limit of primary endpoint failed to meet the pre-specified threshold of 20 %, the clinical efficacy of rituximab is substantial in consideration of the 2 % response rate in the placebo arm in other clinical studies in patients with chronic ITP. We conclude that rituximab is clinically useful and safe in the treatment of Japanese patients with chronic ITP, achieving the goal of maintaining platelet count and reducing risk of bleeding while minimizing treatment-related toxicity.
Full text
Available for:
EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Recently, weight saving of car bodies have been required due to the enhancement of regulations for emissions of CO2, and to improve collision safety, high tensile steel is widely used on car bodies. ...However, joint strength may decrease on high tensile steel. In addition, joint strength depends on fracture mode. Therefore, it is necessary to predict crack propagation direction and investigate the factors which influence the crack propagation direction. In this research, the author has proposed ductile crack analysis method based on continuum damage mechanics. In ductile crack propagation analysis, various potential models have been proposed as damage term. However, in such models, it is difficult to obtain convergence on the calculation of nonlinear constitutive relation. Therefore, in this study, a simplified ductile fracture evaluation method, which is based on the elastic-plastic analysis considering large deformation and strain, was proposed. The proposed method was applied to the analysis of cross tension test on spot weld joints. As a result, it was found that crack propagates along the outer periphery of the weld nugget on larger nugget diameter. These fracture modes are called plug fracture and higher cross tensile strength can be obtained in plug fracture. However, in smaller nugget diameter, crack propagates across the internal nugget. It is called interface fracture and joint strength decreases in this fracture mode. These tendencies agree with the results obtained by experiments. Therefore, in this study, it can be said that crack propagation direction can be predicted on cross tension test on spot weld joints by using the proposed method.
PDF
