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71.
72.

Aim

This study aimed to evaluate the treatment result of intensity-modulated radiation therapy (IMRT) in a large number of Japanese patients with prostate cancer.

Background

A total of 1091 patients with localized prostate cancer were recruited between March 2006 and July 2014. The patients were stratified into low- (n = 205 [18.8%]), intermediate- (n = 450 [41.2%]), high- (n = 345 [31.6%]), and very high-risk (n = 91 [8.3%]) groups according to the National Comprehensive Cancer Network classification. All patients were irradiated via IMRT at a dose of 74–78 Gy with or without androgen-deprivation therapy. The mean follow-up period was 50 months (range, 2–120 months).

Results

The biochemical failure-free rate (BFFR), the clinical failure-free rate, and the overall survival rate at the 5-year follow-up for all patients was 91.3%, 96.2%, and 99.1%, respectively. In univariate analysis, the prostate-specific antigen (PSA) levels (≤20 vs. >20 ng/ml) were significantly correlated with BFFR. A trend toward higher BFFR was noted in patients with a Gleason score (GS) of ≤7 than in patients with GS ≥8. In multivariate analysis, only PSA (≤20 vs. >20 ng/ml) was significantly correlated with BFFR. The cumulative incidence rate of gastrointestinal and genitourinary toxicity (≥grade 2) at the 5-year follow-up was 11.4% and 4.3%, respectively.

Conclusions

The findings of this study indicate that IMRT is well tolerated and is associated with both good long-term tumor control and excellent outcomes in patients with localized prostate cancer.  相似文献   
73.
As a novel approach to the mode of medicinal action of garlic, its constituents were comparatively studied with respect to their interactions with membrane lipids to modify the membrane fluidity. Allyl derivatives rigidified tumor cell and platelet model membranes consisting of unsaturated phospholipids and cholesterol at 20–500 μM with the potency being diallyl trisulfide (DATS) > diallyl disulfide (DADS) by preferentially acting on the hydrocarbon cores of lipid bilayers. They were also effective in rigidifying candida cell model membranes prepared with ergosterol and phospholipids at 100–500 μM with the potency being DADS > DATS > diallyl sulfide (DAS), but not bacteria cell model membranes without ergosterol. Alliin, a precursor of these DASs, was not active on any membranes at 500 μM. Both relative intensity and selectivity in membrane effects correlated with those in antiproliferative, antiplatelet and antimicrobial effects. In cell culture experiments, membrane-active DASs inhibited the growth of tumor cells cultured for 24 and 48 h at 20–500 μM to show the potency being DATS > DADS, together with rigidifying cell membranes by acting on their deeper regions more intensively. However, membrane-inactive allyl derivatives were not growth-inhibitory on tumor cells. The membrane lipid interactions of DASs appear to be one of possible mechanisms underlying different effects of garlic.  相似文献   
74.

Objectives

The purpose of this study was to investigate whether adding a low-dose β1-blocker to milrinone improves cardiac function in failing cardiomyocytes and the underlying cardioprotective mechanism.

Background

The molecular mechanism underlying how the combination of low-dose β1-blocker and milrinone affects intracellular Ca2+ handling in heart failure remains unclear.

Methods

We investigated the effect of milrinone plus landiolol on intracellular Ca2+ transient (CaT), cell shortening (CS), the frequency of diastolic Ca2+ sparks (CaSF), and sarcoplasmic reticulum Ca2+ concentration ({Ca2+}SR) in normal and failing canine cardiomyocytes and used immunoblotting to determine the phosphorylation level of ryanodine receptor (RyR2) and phospholamban (PLB).

Results

In failing cardiomyocytes, CaSF significantly increased, and peak CaT and CS markedly decreased compared with normal myocytes. Administration of milrinone alone slightly increased peak CaT and CS, while CaSF greatly increased with a slight increase in {Ca2+}SR. Co-administration of β1-blocker landiolol to failing cardiomyocytes at a dose that does not inhibit cardiomyocyte function significantly decreased CaSF with a further increase in {Ca2+}SR, and peak CaT and CS improved compared with milrinone alone. Landiolol suppressed the hyperphosphorylation of RyR2 (Ser2808) in failing cardiomyocytes but had no effect on levels of phosphorylated PLB (Ser16 and Thr17). Low-dose landiolol significantly inhibited the alternans of CaT and CS under a fixed pacing rate (0.5 Hz) in failing cardiomyocytes.

Conclusion

A low-dose β1-blocker in combination with milrinone improved cardiac function in failing cardiomyocytes, apparently by inhibiting the phosphorylation of RyR2, not PLB, and subsequent diastolic Ca2+ leak.  相似文献   
75.
Species of predatory Coleoptera have become abundant in new geographic regions recently, raising concerns for invaded ecosystems. We address this topic by focusing on invasive alien ladybird beetles (Coccinellidae; known also as ladybugs). Humans appear directly or indirectly responsible for all or most ladybird invasions. Factors hypothesized to have promoted ladybird invasions include genetic diversity (e.g., for polymorphism), phenotypic plasticity, adaptation and genetic shift, generalized diet and habitat preferences, flexible life history and reproduction, large body size, and release from enemies. Factors such as climate, habitat and prey availability, and biotic resistance may sometimes prevent or slow ladybird invasions. Indigenous species (e.g., herbivores) may suffer from invasions, and biological control programs may be affected. Species of indigenous ladybirds throughout the world are reported to have declined in abundance following ladybird invasions, with increased competition and/or intraguild predation most often hypothesized or inferred. Similar recent studies especially of ground beetles (Carabidae) also make clear the potential of invasive alien predatory Coleoptera to disrupt invaded natural and agricultural ecosystems.  相似文献   
76.
ATP-Activated Nonselective Cation Current in NG108-15 Cells   总被引:5,自引:0,他引:5  
Abstract: ATP (1 mM) induced a biphasic increase in intracellular Ca2+ concentration ([Ca2+]i), i.e., an initial transient increase decayed to a level of sustained increase, in NG108-15 cells. The transient increase was inhibited by a phospholipase C inhibitor, 1-[6-[[17β-3-methoxyestra-1,3,5(10)-trien-17-yl]amino]hexyl]-1H-pyrrole-2,5-dione (U73122), whereas the sustained increase was abolished by removal of external Ca2+. We examined the mechanism of the ATP-elicited sustained [Ca2+]i increase using the fura-2 fluorescent method and the whole-cell patch clamp technique. ATP (1 mM) induced a membrane current with the reversal potential of 12.5 ± 0.8 mV (n = 10) in Tyrode external solution. The EC50 of ATP was ~0.75 mM. The permeability ratio of various cations carrying this current was Na+ (defined as 1) > Li+ (0.92 ± 0.01; n = 5) > K+ (0.89 ± 0.03; n = 6) > Rb+ (0.55 ± 0.02; n = 6) > Cs+ (0.51 ± 0.01; n = 5) > Ca2+ (0.22 ± 0.03; n = 3) > N-methyl-d -glucamine (0.13 ± 0.01; n = 5), suggesting that ATP activated a nonselective cation current. The ATP-induced current was larger at lower concentrations of external Mg2+. ATP analogues that induced the current were 2-methylthio-ATP (2MeSATP), benzoylbenzoic-ATP, adenosine 5′-thiotriphosphate (ATPγS), and adenosine 5′-O-(2-thiodiphosphate), but not adenosine, ADP, α,β-methylene-ATP (AMPCPP), β,γ-methylene-ATP (AMPPCP), or UTP. Concomitant with the current data, 2MeSATP and ATPγS, but not AMPCPP or AMPPCP, increased the sustained [Ca2+]i increase. We conclude that ATP activates a class of Ca2+-permeable nonselective cation channels via the P2z receptor in NG108-15 cells.  相似文献   
77.
78.
79.
Dissolved organic matter (DOM) in seawater can be defined as the fraction of organic matter that passes through a filter of sub micron pore size. In this study, we have examined the effect of DOM of deep seawater (DSW) from Pacific Ocean on platelet aggregation and atherosclerosis progression. DSW was passed through a series of filters and then through an Octadecyl C18 filter; the retained substance in ethanol was designated as C18 extractable DOM (C18-DOM). Our studies showed that C18-DOM treatment inhibited platelet aggregation, P-selectin expression and activity of COX-1 significantly. C18-DOM increased the expression of anti-atherogenic molecule namely heme oxygenase-1 in endothelial cells and all these data showed that C18-DOM is exhibiting aspirin-like effects. Moreover our in vivo studies showed that C18-DOM feeding slowed remarkably the progression of atherosclerosis. Our study demonstrated a novel biological effect of oceanic DOM, which has several important implications, including a possible therapeutic strategy for atherosclerosis.  相似文献   
80.
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is causing the global coronavirus disease 2019 (COVID-19) pandemic. Because complete elimination of SARS-CoV-2 appears difficult, decreasing the risk of transmission is important. Treatment with 0.1 and 0.05 ppm ozone gas for 10 and 20 hr, respectively, decreased SARS-CoV-2 infectivity by about 95%. The magnitude of the effect was dependent on humidity. Treatment with 1 and 2 mg/L ozone water for 10 s reduced SARS-CoV-2 infectivity by about 2 and 3 logs, respectively. Our results suggest that low-dose ozone, in the form of gas and water, is effective against SARS-CoV-2.  相似文献   
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