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71.
In recent years, several glycosyl indolocarbazole derivatives have been developed as antitumor agents targeting the topoisomerase I-DNA complex and a few of them were evaluated in clinical trials. The lead drug in the series is compound A which bears a formylamino substituent on the N-imide F-ring. This compound has shown promising antitumor activities in vivo and was tested clinically but it has been recently replaced with a more active analogue, J-107088, bearing a (hydroxymethyl-2-hydroxy) ethylamino substituent on the N-imide F-ring. We have compared the plasma stability of two molecules in this series, compounds A and D, which only differ by the nature of the group on the imide ring. The conversion of the compounds into the anhydride species B was studied by HPLC and the resulting metabolite, formed both in human plasma ultrafiltrate and in water, was characterized by NMR and mass spectrometry. Absorption measurements provided a facile method to follow the conversion of compounds A and D into their metabolite product B. Altogether, the experimental data demonstrate that the replacement of the NHCHO substituent of compound A with a hydrophilic NHCH(CH(2)OH)(2) chain preserves the intact imide function that is known to be essential for topoisomerase I inhibition and cytotoxicity. The transformation of compound A into the anhydride metabolite B (or its diacid open form) occurs much more slowly compared to compound D. Half-life parameter t(1/2) of 67 and 245 min(-1) were calculated for compounds A and D, respectively. A molecular modeling analysis, performed to compare the conformation and electronic properties of compounds A and D, offers a rational explanation for the gain of chemical stability of the indolocarbazole derivative D. The data provide important information for the rational design of antitumor indolocarbazole derivatives.  相似文献   
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We have compared the levels of immunoglobulins G (IgG) and G4 (IgG4) in extreme seropositive patients from the GRIV cohort consisting of 168 patients with slow progression (SP) and 60 with rapid progression (RP) as well as in 173 healthy controls. IgG levels were significantly higher in SP patients than in RP patients (P = 0.008), both higher than in seronegative individuals. IgG4 levels were significantly lower in SP patients than in RP patients (P = 0.001), both lower than in seronegative individuals. We tried to correlate these levels with biological parameters (CD4(+) and CD8(+) cells, total lymphocytes, white blood cell counts, percentage of CD4(+) cells, and viral load) as well as with genetic markers from Th1/Th2 cytokines (IL2, IL4, IL6, IL10, IL13, and IFNgamma). IgG levels were correlated with the percentage of CD4(+) cells in SP while IgG4 levels were correlated with CD8(+) cell count in SP and with percentage of CD4(+) cells in RP patients. Among the parameters measured in SP patients at the time of inclusion in the study, the best predictor of progression towards AIDS was the viral load, the best predictor for stability was CD4(+) cell count, but overall, the best predictor for SP evolution (stability vs. progression) appeared to be the percentage of CD4(+) cells. Interestingly, correlations between the levels of IgG or IgG4 and the cytokine gene polymorphisms were found, notably in the IL10 gene.  相似文献   
75.

Purpose

To demonstrate the benefits of fluorescence-supported extended pelvic lymph node dissection (ePLND) compared to regular ePLND in robot-assisted radical prostatectomy.

Methods

120 patients with intermediate- or high-risk prostate cancer were prospectively randomized (1:1): in the intervention group, indocyanine green (ICG) was injected transrectally into the prostate before docking of the robot. In both groups, ePLND was performed including additional dissection of fluorescent lymph nodes (LN) in the ICG group.

Results

After drop-out of two patients, 59 patients were allocated to the control (A) and intervention group (B) with a median PSA of 8,6 ng/ml. Median console time was 159 (A) vs. 168 (B) min (p?=?0.20) with a longer time for ICG-ePLND: 43 (A) vs. 55 min (B) (p?=?0.001). 2609 LN were found with significantly more LN after ICG-supported ePLND with a median of 25 vs. 17 LN in A (p?<?0.001). Nodal metastases were detected in 6 patients in A (25 cancerous LN) vs. 9 patients in B (62 positive LN) (p?=?0.40). In seven of nine patients, ICG-ePLND identified at least one cancer-positive LN (sensitivity 78%), 27 of 62 cancerous LN were fluorescent. Symptomatic lymphocele occurred in one patient in a and in three patients in b (p?=?0.62). After a median follow-up of 22.9 months, PSA levels were similar.

Conclusions

While ICG-ePLND seems to be beneficial for a better understanding of the lymphatic drainage and a more meticulous diagnostic approach, the sensitivity is not sufficient to recommend stand-alone ICG lymph node dissection.
  相似文献   
76.
Objective Prolonged controlled mechanical ventilation (MV) is known to induce diaphragmatic oxidative stress that seems to be an important factor reducing force-generating capacity. To better understand the cellular mechanisms involved, this work examined the effect of short vs. prolonged MV on antioxidant defense in the diaphragm.Design and setting Prospective, randomized, controlled animal study in a university laboratory.Methods Eleven piglets (15–20 kg) were assigned to one of two groups: a long-MV group (n=6) ventilated for 3 days or a short-MV group (n=5) ventilated for 3 h. Force frequency curves of the transdiaphragmatic pressure (Pdi) were obtained in vivo by phrenic nerve pacing. Oxidative stress was evaluated by thiobarbituric reactive substance (TBARs) content and the enzymatic antioxidant activity of both superoxide dismutase (SOD) and glutathione peroxidase (GPx) in samples of diaphragm.Results Pdi decreased in the long-MV group by 30–35% over the 3 days at all frequencies compared to the short-MV group. Diaphragm TBARs content was significantly higher and SOD activity lower in long-MV animals than in short-MV animals after 72 h. GPx activity tended to be lower in diaphragms from long-MV animals, but this difference was not significant.Conclusions This study shows that 3 days of MV in piglets is associated with a decrease in antioxidant activity which could emphasize oxidative stress and both contribute to the diaphragm dysfunction caused by MVElectronic Supplementary Material Electronic supplementary material to this paper can be obtained by using the Springer Link server located at .S. Jaber and M. Sebbane contributed equally to this study.This article refers to the editorial  相似文献   
77.

Introduction

The phase III MPACT trial in patients with metastatic pancreatic cancer (MPC) demonstrated superior efficacy of nab-paclitaxel (nab-P) plus gemcitabine (Gem) compared with Gem monotherapy, including the primary endpoint of overall survival (OS; median 8.7 vs. 6.6 months; hazard ratio [HR] 0.72; P < 0.001). A significant treatment difference favoring nab-P + Gem over Gem was observed for OS in patients treated in North America. The majority of patients were from the US (88%) with only 12% from Canada. Healthcare systems and treatment patterns are different between the 2 countries, and there is limited published information on outcomes of Canadian patients treated with first-line nab-P + Gem. This analysis evaluated efficacy and safety outcomes in Canadian patients in the MPACT trial.

Methods

Treatment-naive patients with MPC (N = 861) received either nab-P 125 mg/m2 + Gem 1000 mg/m2 on days 1, 8, and 15 every 4 weeks or Gem 1000 mg/m2 weekly for the first 7 of 8 weeks (cycle 1) and then on days 1, 8, and 15 every 4 weeks (cycle ≥2).

Results

The MPACT trial enrolled 63 patients in Canada. Baseline characteristics were well balanced and comparable with those of the intent-to-treat population. Both OS (median 11.9 vs. 7.1 months; HR 0.76; P = 0.373) and progression-free survival (median 7.2 vs. 5.2 months; HR 0.65; P = 0.224) were numerically longer and overall response rate (27% vs. 17%; P = 0.312) was numerically higher with nab-P + Gem vs. Gem. The most common grade ≥3 adverse events with nab-P + Gem vs. Gem were neutropenia (22% vs. 10%), fatigue (34% vs. 33%), and neuropathy (25% vs. 0%).

Conclusion

This subanalysis confirmed that nab-P + Gem is an efficacious treatment option and has a manageable safety profile in patients with MPC treated in Canada.

Trial registration

ClinicalTrials.gov identifier, NCT00844649.

Funding

Celgene Corporation, Summit, NJ, USA.
  相似文献   
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EphA7 is expressed in the adult central nervous system (CNS), where its roles are yet poorly defined. We mapped its distribution using in situ hybridization (ISH) and immunohistochemistry (IHC) combined with light (LM) and electron microscopy (EM) in adult rat and mouse brain. The strongest ISH signal was in the hippocampal pyramidal and granule cell layers. Moderate levels were detected in habenula, striatum, amygdala, the cingulate, piriform and entorhinal cortex, and in cerebellum, notably the Purkinje cell layer. The IHC signal distribution was consistent with ISH results, with transport of the protein to processes, as exemplified in the hippocampal neuropil layers and weakly stained pyramidal cell layers. In contrast, in the cerebellum, the Purkinje cell bodies were the most strongly immunolabeled elements. EM localized the cell surface‐expression of EphA7 essentially in postsynaptic densities (PSDs) of dendritic spines and shafts, and on some astrocytic leaflets, in both hippocampus and cerebellum. Perikaryal and dendritic labeling was mostly intracellular, associated with the synthetic and trafficking machineries. Immunopositive vesicles were also observed in axons and axon terminals. Quantitative analysis in EM showed significant differences in the frequency of labeled elements between regions. Notably, labeled dendrites were ~3–5 times less frequent in cerebellum than in hippocampus, but they were individually endowed with ~10–40 times higher frequencies of PSDs, on their shafts and spines. The cell surface localization of EphA7, being preferentially in PSDs, and in perisynaptic astrocytic leaflets, provides morphologic evidence that EphA7 plays key roles in adult CNS synaptic maintenance, plasticity, or function. J. Comp. Neurol. 524:2462–2478, 2016. © 2016 Wiley Periodicals, Inc.  相似文献   
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