Leucovorin and Fluorouracil With or Without Oxaliplatin as First-Line Treatment in Advanced Colorectal Cancer.

PURPOSE: In a previous study of treatment for advanced colorectal cancer, the LV5FU2 regimen, comprising leucovorin (LV) plus bolus and infusional fluorouracil (5FU) every 2 weeks, was superior to the standard North Central Cancer Treatment Group/Mayo Clinic 5-day bolus 5FU/LV regimen. This phase III study investigated the effect of combining oxaliplatin with LV5FU2, with progression-free survival as the primary end point. PATIENTS AND METHODS: Four hundred twenty previously untreated patients with measurable disease were randomized to receive a 2-hour infusion of LV (200 mg/m2/d) followed by a 5FU bolus (400 mg/m2/d) and 22-hour infusion (600 mg/m2/d) for 2 consecutive days every 2 weeks, either alone or together with oxaliplatin 85 mg/m2 as a 2-hour infusion on day 1. RESULTS: Patients allocated to oxaliplatin plus LV5FU2 had significantly longer progression-free survival (median, 9.0 v 6.2 months; P = .0003) and better response rate (50.7% v 22.3%; P = .0001) when compared with the control arm. The improvement in overall survival did not reach significance (median, 16.2 v 14.7 months; P = .12). LV5FU2 plus oxaliplatin gave higher frequencies of National Cancer Institute common toxicity criteria grade 3/4 neutropenia (41.7% v 5.3% of patients), grade 3/4 diarrhea (11.9% v 5.3%), and grade 3 neurosensory toxicity (18.2% v 0%), but this did not result in impairment of quality of life (QoL). Survival without disease progression or deterioration in global health status was longer in patients allocated to oxaliplatin treatment (P = .004). CONCLUSION: The LV5FU2-oxaliplatin combination seems beneficial as first-line therapy in advanced colorectal cancer, demonstrating a prolonged progression-free survival with acceptable tolerability and maintenance of QoL.

A modular spring-loaded actuator for mechanical activation of membrane proteins.

How cells respond to mechanical forces by converting them into biological signals underlie crucial cellular processes. Our understanding of mechanotransduction has been hindered by technical barriers, including limitations in our ability to effectively apply low range piconewton forces to specific mechanoreceptors on cell membranes without laborious and repetitive trials. To overcome these challenges we introduce the Nano-winch, a robust, easily assembled, programmable DNA origami-based molecular actuator. The Nano-winch is designed to manipulate multiple mechanoreceptors in parallel by exerting fine-tuned, low- piconewton forces in autonomous and remotely activated modes via adjustable single- and double-stranded DNA linkages, respectively. Nano-winches in autonomous mode can land and operate on the cell surface. Targeting the device to integrin stimulated detectable downstream phosphorylation of focal adhesion kinase, an indication that Nano-winches can be applied to study cellular mechanical processes. Remote activation mode allowed finer extension control and greater force exertion. We united remotely activated Nano-winches with single-channel bilayer experiments to directly observe the opening of a channel by mechanical force in the force responsive gated channel protein, BtuB. This customizable origami provides an instrument-free approach that can be applied to control and explore a diversity of mechanotransduction circuits on living cells.

An achiral ferromagnetic/chiral antiferromagnetic bilayer system leading to controllable size and density of skyrmions.

Magnetic skyrmions are topologically protected domain structures related to the Dzyaloshinskii-Moriya interaction (DMI). To understand how magnetic skyrmions occur under different circumstances, we propose a model for skyrmion formation in a bilayer system of ferromagnetic/antiferromagnetic (FM/AFM) films, in which the bulk DMI is only present in the AFM film. Micromagnetic simulations reveal that skyrmions are formed in this system due to the competition between the DMI and demagnetization energies. A critical interfacial exchange energy (Ai = 6.5 mJ/m2) is determined, above which the competition occurs at its full extent. More skyrmions are formed with increasing external magnetic field till a critical value above which the external field is too large and thus leading to the annihilation of skyrmions. The spacing between two skyrmions can be as small as 45 nm. Our results may give technological implications for future skyrmion applications.

5-year overall survival after early breast cancer diagnosed during pregnancy: A retrospective case-control multicentre French study.

BACKGROUND: Breast cancer diagnosed during pregnancy (BCP) is rare, but the prevalence is expected to rise. Long-term follow-up data regarding this clinically challenging condition are scarce. The main objective of this multicentre case-control French study was to compare the survival between pregnant patients and matched controls. METHODS: Patients from 27 centres diagnosed between 2000 and 2009 with histologically proven invasive breast cancer occurring during pregnancy were retrospectively included. Controls were matched to BCP patients on age, clinical T stage, hormone receptor, HER2, administration of neo-adjuvant chemotherapy and pathological node involvement in the absence of neo-adjuvant chemotherapy. Five-year overall survival (OS), disease-free survival (DFS) and metastasis-free survival (MFS) rates were estimated using the Kaplan-Meier method. RESULTS: One hundred and eleven BCP patients and 253 controls were included. Median age was 33 and 35 years, respectively. Both populations were managed similarly, except for less frequent sentinel node dissection (p = 0.026) and taxane administration (p = 0.03) among BCP patients. Median follow-up was 7.5 years. Survival rates were similar between both BCP and control patients: 5-year OS rates were 83.1% (95% CI: 74.5-89.0) vs 85.5% (95% CI: 80.4-89.4), respectively, p = 0.31; 5-year DFS rates 60.0% (95% CI: 50.1-68.6) vs 68.5% (95% CI: 62.3-73.9), respectively, p = 0.12 and 5-year MFS rates 71.0% (95% CI: 61.3-78.6) and 74.5% (95% CI: 68.6-79.5), respectively, p = 0.21. CONCLUSION: Our study showed that the survival outcomes of patients diagnosed with BCP were not significantly different as compared to those of matched non-pregnant controls. A proper management of women diagnosed with BCP is crucial.

Deterioration of the coercivity due to the diffusion induced interface layer in hard/soft multilayers.

Hard/soft permanent magnets have aroused many interests in the past two decades because of their potential in achieving giant energy products as well as their rich variety of magnetic behaviors. Nevertheless, the experimental energy products are much smaller than the theoretical ones due to the much smaller coercivity measured in the experiments. In this paper, the deterioration of the coercivity due to the interface atomic diffusion is demonstrated based on a three dimensional (3D) micromagnetic software (OOMMF) and a formula derived for the pinning field in a hard/soft multilayer, which can be applied to both permanent magnets and exchange-coupled-composite (ECC) media. It is found that the formation of the interface layer can decrease the coercivity by roughly 50%, which is responsible for the observed smaller coercivity in both composite and single-phased permanent magnets. A method to enhance the coercivity in these systems is proposed based on the discussions, consistent with recent experiments where excellent magnetic properties are achieved.

Skyrmion-skyrmion and skyrmion-edge repulsions in skyrmion-based racetrack memory.

Magnetic skyrmions are promising for building next-generation magnetic memories and spintronic devices due to their stability, small size and the extremely low currents needed to move them. In particular, skyrmion-based racetrack memory is attractive for information technology, where skyrmions are used to store information as data bits instead of traditional domain walls. Here we numerically demonstrate the impacts of skyrmion-skyrmion and skyrmion-edge repulsions on the feasibility of skyrmion-based racetrack memory. The reliable and practicable spacing between consecutive skyrmionic bits on the racetrack as well as the ability to adjust it are investigated. Clogging of skyrmionic bits is found at the end of the racetrack, leading to the reduction of skyrmion size. Further, we demonstrate an effective and simple method to avoid the clogging of skyrmionic bits, which ensures the elimination of skyrmionic bits beyond the reading element. Our results give guidance for the design and development of future skyrmion-based racetrack memory.

Absence of estrogen receptor-related-alpha increases osteoblastic differentiation and cancellous bone mineral density.

The nuclear orphan receptor human estrogen receptor-related receptor (ERR)-alpha is implicated in bone metabolism. We studied the effect of ERRalpha silencing in human mesenchymal stem cells (hMSCs) during osteoblastogenesis. We found that ERRalpha silencing led to an increase of bone sialoprotein and a decrease of osteopontin mRNA levels, suggesting enhanced osteoblastic differentiation. This was confirmed by an increased ability of hMSCs to deposit calcium. Concomitantly, knockdown of ERRalpha inhibited adipogenesis, resulting in a decrease in adipocyte number and adipocyte marker gene expression. In line with a negative role of ERRalpha in bone metabolism, we found that adult female and male ERRalpha-deficient mice displayed a moderate increase in femoral cancellous bone volume and density. Osteoblast surface was increased and marrow fat volume decreased in these animals. Furthermore, ERRalpha-deficient osteoblasts displayed increased differentiation properties in vitro in line with our observations in hMSCs. In summary, we identified a role for ERRalpha in bone mass regulation by affecting osteoblastic differentiation.

Randomized phase II study evaluating oxaliplatin alone, oxaliplatin combined with infusional 5-FU, and infusional 5-FU alone in advanced pancreatic carcinoma patients.

BACKGROUND: A randomized phase II, open-label multicenter study evaluating oxaliplatin alone (OXA), infusional 5-fluorouracil alone (5-FU) and an oxaliplatin/infusional 5-FU combination (OXFU) in untreated, advanced pancreatic carcinoma (APC). PATIENTS AND METHODS: Chemotherapy-naïve patients with advanced or metastatic, histologically/cytologically proven pancreatic carcinoma with measurable disease, received OXA [130 mg/m2, 2-h intravenous (i.v.) infusion] alone, OXA combined with 5-FU (1000 mg/m2/day, continuous i.v., days 1-4), or 5-FU alone, every 3 weeks. RESULTS: Sixty-three patients (42 males/21 females) were treated: 17 patients/52 cycles OXA, 31 patients/ 175 cycles OXFU, 15 patients/41 cycles 5-FU, with a median of three, six and two cycles/patient, respectively. Patient characteristics were similar in all arms. Median age was 57 years (range 21-75), and 83% of patients had PS 0-1. Most patients (62%) had moderate to well-differentiated tumors, 90% had metastatic disease, 81% with liver metastases. All responses (three partial responses; WHO) occurred in the OXFU arm (10% response rate). Five of 32 patients evaluable for clinical benefit were responders (OXA, 14%; OXFU, 21%). Median time to progression and overall survival were higher in the combination arm (4.2 and 9.0 months, respectively) than either single-agent arm (OXA, 2.0 and 3.4 months; 5-FU, 1.5 and 2.4 months, respectively). Moderate hematotoxicity without morbidity was seen in all arms. Two OXFU patients had grade 3 oxaliplatin neurosensory toxicity. CONCLUSIONS: With a 10% response rate, median overall survival of 9 months and an encouraging safety profile, the OXFU combination is effective, appears superior to infusional 5-FU and warrants further studies in APC patients.

Synthesis of oligonucleotide prodrugs bearing N-acetyl nucleobases.

N-Acetyl oligonucleotides and their prodrugs were synthesized on photolabile solid support. Tm studies showed a decrease of hydridization for N-acetyl A and G and an increase for N-acetyl C. In cells extract, acetyl groups were hydrolysed.

A new approach to treat tissue destruction in periodontitis with chemically modified dextran polymers.

Periodontitis are diseases of the supportive tissues of the teeth provoked by bacteria and characterized by gingival inflammation and bone destruction. We have developed a new strategy to repair tissues by administrating agents (RGTA) that mimic heparan sulfates by protecting selectively some of the growth factors naturally present within the injured tissue and interfering with inflammation. After periodontitis induction in hamsters, the animals were left untreated or received weekly i.m. injections of RGTA1507 at a dose of 100 microg/kg, 400 microg/kg, 1.5 mg/kg, or 15 mg/kg for 4 wk. RGTA treatment significantly reduced gingival tissue inflammation, thickened the pocket epithelium by increasing cell proliferation, and enhanced collagen accumulation in the gingiva. A marked reduction in bone loss was observed, resulting from depression of osteoclasia and robust stimulation of bone formation at the dose of 1.5 mg/kg. RGTA treatment for 8 wk at this dose reversed macroscopic bone loss, sharply contrasting with the extensive bone destruction in the untreated animals. RGTA treatment decreased gelatinase A (MMP-2) and B (MMP-9) pro-forms in gingival tissues. Our data indicate that a 4 wk treatment dose-dependently attenuated gingival and bone manifestations of the disease, whereas a longer treatment restored alveolar bone close to controls. By modulating and coordinating host responses, RGTA has unique therapeutic properties and is a promising candidate for the treatment of human periodontitis.

Chemical sympathectomy-induced changes in TH-, VIP-, and CGRP-immunoreactive fibers in the rat mandible periosteum: influence on bone resorption.

The expression of neurotransmitter receptors by bone cells supports the concept that the nervous system is a regulator of bone metabolism. The discrimination of the respective roles of the sensory and sympathetic nervous systems requires evidence of topographic relationships between the corresponding fibers and the cells involved in bone turnover, in vivo. In this study, the influence of the sympathetic system on bone resorption was assessed by using a synchronized model of cortical resorption along the mandible. The sympathetic system was destroyed by daily injections of guanethidine (40 mg/kg) for 25 days; a resorption wave was induced on day 21. The distribution of periosteal tyrosine-hydroxylase (TH)-, vasoactive intestinal polypeptide (VIP)-, and calcitonin gene-related peptide (CGRP)-immunoreactive (IR) fibers was studied by compartmentalizing the periosteum. Most fibers were located in the distal, non-osteogenic compartment. TH-IR fibers were located perivascularly, VIP-IR fibers were gathered at the boundary with the osteogenic compartment, and CGRP-IR fibers were scattered. Sympathectomy decreased the number of TH- and VIP-IR fibers and increased the number of CGRP-IR fibers, without changing their topography. After the injection of Fast blue, a retrograde fluorescent marker, over the periosteum, fluorescent neuronal cell bodies were found in the superior cervical ganglion (SCG). Many neurons were TH-IR and very few were VIP-IR. Sympathectomy decreased the numbers of fluorescent and TH-IR cell bodies. It also decreased the number of preosteoclasts and osteoclasts, which had a drastic effect on the cortical bone surface, as assessed by scanning electron microscopy. These data indicate that VIP-IR fibers have a strategic position close to the most peripheral and less differentiated, osteogenic cells, pointing to a functional relationship. As poorly differentiated osteogenic cells support preosteoclast differentiation, VIP-IR fibers may be involved in this process, as suggested by the smaller number of preosteoclasts in sympathectomized rats. Although VIP is predominantly a parasympathetic mediator, it seemed to be conveyed by sympathetic fibers, as shown by the marked effect of guanethidine treatment. Nevertheless, these fibers did not originate from the SCG, contrary to TH-IR fibers.

Use of MALDI-TOF mass spectrometry to monitor solid-phase synthesis of oligonucleotides.

MALDI-TOF mass spectrometry has been used to characterize solid-supported oligonucleotides containing natural and non-natural and non-nucleoside moieties and a variety of internucleosidic linkages including phosphate and phosphite triesters and H-phosphonate diesters. This technique was used to follow the reactions involved in oligonucleotide synthesis; this enabled direct control of the elongation and optimization of the coupling process.

Use of 2-(tert-butyldiphenylsilyloxymethyl) benzoyl as N-protecting group for the synthesis of prooligonucleotides.

A short TCCT Me-SATE prooligonucleotide was successfully synthesized using 2-(tert-butyldiphenyloxymethyl) benzoyl protecting group, after its removal by means of trimethylsilyl chloride and water.

Cellular uptake and intracellular quantification of fluorescent labeled T20 Me-SATE prooligonucleotides.

Fluorescein labeled Me-SATE T20 models were synthesized. The high uptake of these prooligos in HeLa cells was confirmed by fluorescence microscopy, flow cytometry and by spectrofluorometry.

Kinetics study of the biotransformation of an oligonucleotide prodrug in cells extract by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.

The fate of a dodecathymidine prodrug in cell extract was monitored by MALDI-TOF MS. This technique allows a facile identification and a relative quantification of metabolites produced. We showed that the relative peak intensities were similar to the relative metabolite proportions that permitted the determination of their half-lives. The oligonucleotide prodrug was fully metabolized to yield the T12 phosphorothioate likely through a carboxyesterase mediated mechanism.

Polyimidazole conjugated oligonucleotides reach the nucleus of HeLa cells.

Oligonucleotide models bearing 6, 12 or 18 histamine residues were synthesized on solid support and labeled with fluorescein. Only the oligo with 6 histamine residues showed a high uptake in HeLa cells with a nuclear localization. Experiment a 4 degrees C or with bafilomicyn A1 suggest that uptake proceeded by an endocytosis mechanism followed by a destabilization of the membrane. Once in the cytoplasm the oligo reached rapidly the nucleus.

Direct MALDI-TOF MS analysis of oligonucleotides on solid support through a photolabile linker.

MALDI-TOF mass spectrometry was used to analyze oligonucleotides still anchored to long-chain alkylamine controlled-pore glass (LCAA-CPG) through a photolabile linker. This technique is useful to follow supported chemical reactions in real time and monitor by-products formation.

Triple, MPEG-conjugated, helix-forming oligonucleotides (TRIPEGXs): liquid-phase synthesis of natural and chimeric "all-purine" sequences linked to high molecular weight poly(ethylene glycols).

Long "all-purine" oligonucleotides, up to the 20mer, known to be active as antigene effectors, conjugated to high molecular weight monomethoxy poly(ethylene glycol)s (MPEG)s, were successfully synthesized. Through a liquid-phase, MPEG-supported process, both natural and chimeric sequences containing selected phosphorothioate backbone modifications were obtained, purified, and characterized. To follow their cellular trafficking, a fluorescent probe was linked by soluble supported organic reactions to the 5'-terminus, and the efficiency of the different synthetic procedures for the introduction of a fluorescein moiety was compared. The usefulness of the fluorescent marker was estimated by laser confocal microscopy that ascertains that the MPEG-conjugation enhances the oligonucleotide capacity to cross the cellular membranes and to be accumulated inside the nuclei.

Kinetics study of the biotransformation of an oligonucleotide prodrug in cells extract by matrix-assisted laser desorption-ionization time-of-flight mass spectrometry.

The fate of a dodecathymidine prodrug in cell extract was monitored by MALDI-TOF MS. This technique allows a facile identification and a relative quantification of metabolites produced. We showed that the relative peak intensities were similar to the relative metabolite proportions that permitted the determination of their half-lives. We found a good fit between the calculated kinetics curves and the experimental points. The oligonucleotide prodrug was fully metabolized to yield the dodecathymidine phosphorothioate likely through a carboxyesterase mediated mechanism.

PMMA-based composite materials with reactive ceramic fillers: IV. Radiopacifying particles embedded in PMMA beads for acrylic bone cements.

New acrylic bone cements were prepared from alumina particles previously treated by 3-(trimethoxysilyl)propylmethacrylate (gamma-MPS) and embedded in poly(methylmethacrylate-co-ethylacrylate) beads with about 7 mol% of ethyl acrylate repeating units. The encapsulation was performed through a conventional suspension polymerization process. The influence of (i) the concentration of the dispersion stabilizer and (ii) the alumina content upon the shape, size, and size distribution of the acrylic beads was studied. Cements were prepared from each batch by hand-mixing alumina-filled acrylic beads with a liquid monomer mixture containing methyl methacrylate, n-butyl methacrylate, and N,N-dimethyl-p-toluidine. Benzoyl peroxide was previously added to the solid part. The powder-to-liquid ratio was equal to 2 for each formulation. Compressive strength of cured cement decreases with alumina content, whereas compressive modulus remains roughly constant. These results are in contradiction to those obtained for cements based on a mixture of gamma-MPS-treated alumina and unfilled acrylic beads. Nevertheless, they are interpreted in terms of alumina arrangement in the cement. In the first case, alumina particles contribute to the reinforcement of the dispersed acrylic phase, with poor benefits for the whole materials. In the second case, they allow the reinforcement of the continuous acrylic phase and, therefore, the cement's one.