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The use of surrogate outcomes that predict treatment effect on an unobserved true outcome may have substantial economic and ethical advantages, through reducing the length and size of clinical trials. There has been extensive investigation of the best means of evaluating putative surrogates. We present a systematic review on the evolution of statistical methods for validating surrogates starting from the defining paper of Prentice (1989). We highlight the fundamental differences in the current statistical evaluation approaches, their advantages and disadvantages, and examine the understanding and perceptions of investigators in this area. [ABSTRACT FROM AUTHOR]

Previous study has shown human serum albumin (HSA) coated liposomes can deliver bcl-2 antisense oligodeoxyribonucleotide (ODN) into KB carcinoma cells, and decrease bcl-2 mRNA and protein expression level. In the current study, cell growth inhibition and chemosensitization of KB cells were evaluated. Liposomes composed of dimethyldioctadecyl ammonium bromide/egg phosphatidylcholine/α-tocopheryl polyethylene glycol 1000 succinate (58:40:2 molar ratio) complexed with bcl-2 antisense ODN and coated with HSA were examined for cell growth inhibition and sensitization to a commonly used chemotherapeutic drug, doxorubicin. HSA-coated liposome-ODN complexes effectively inhibited cell growth in the range of ODN concentration of 0.45-7.2 µM. Upon posttreatment with doxorubicin, the cytotoxicity was further significantly increased compared to the ODN complexes alone. The cytotoxicity was dependent on antisense ODN concentration, incubation time and doxorubicin concentration, and relatively independent on HSA concentration. This study suggests that HSA-coated liposomes are effective delivery vehicles for antisense ODN with potential therapeutic application and can be effectively combined with doxorubicin. [ABSTRACT FROM AUTHOR]

What do new coaches learn as they become proficient in this profession? Based on experience as director of a coach certification program, the author describes learnings that go beyond the basic structure and process of executive coaching. These are in the categories of Seeing, Listening, Being Who You Are, Taking Action, and Believing in Coaching. [ABSTRACT FROM AUTHOR]

Consulting psychologists and executives work well together when they develop a solid bond, yet can productively benefit from their differing perspectives and needs. This article is based on a workshop at the 2003 conference of the Society of Psychologists in Management (SPIM) that examined similarities and differences between executives and the psychologist-consultants who work with them and explored how these similarities and differences help or hinder their work together. Similarities can get in the way, differences can be a most valuable asset, or the reverse can be true, depending on how well they are understood and managed within the relationship between the executive and the psychologist-consultant. Data from 4 well-established inventories were used to determine similarities and differences. The experiences of workshop participants (including a panel of SPIM leaders) were used to explore how similarities and differences make a difference in a consulting relationship. [ABSTRACT FROM AUTHOR]

This study investigated the effect of structural modification of Curcumin (CU) combined with the solid lipid nanoparticles (SLN) drug delivery system on anti-tumor activity in vitro. A new structure of Curcumin derivative (CU1) was successfully synthesized by modifying the phenolic hydroxyl group of CU. CU1 was two times more stable than CU at 45 °C or constant light. The SLN containing CU1 (CU1-SLN) was prepared, and the particle size, polydispersity index, entrapment efficiency, drug loading, and zeta potential of CU1-SLN were (104.1 ± 2.43) nm, 0.22 ± 0.008, (95.1 ± 0.38) %, (4.28 ± 0.02) %, and (28.3 ± 1.60) mV, respectively. X-ray diffraction (XRD) and Differential scanning calorimetry (DSC) showed that CU1 is amorphous in SLN. CU1-SLN released the drug slowly for 48 h, while CU and CU1 were released rapidly within 8 h. In terms of cytotoxicity, CU1 exhibited a 1.5-fold higher inhibition than CU against A549 and SMMC-7721 cells, while CU1-SLN showed 2-fold higher inhibition than CU1. Both CU1 and CU1-SLN reduced the toxicity in normal hepatocytes compared with CU (2.6-fold and 12.9-fold, respectively). CU1-SLN showed a significant apoptotic effect (p < 0.05). In summary, CU1 retained the inhibitory effect of CU against tumor cells, while improving stability and safety. Additionally, CU1-SLN presents a promising strategy for the treatment of liver and lung cancer. [ABSTRACT FROM AUTHOR]

The main aim of this study was to improve the therapeutic potential of a paclitaxel (PTX) and curcumin (CU) combination regimen using solid lipid nanoparticles (SLNs). PTX and CU were successfully coencapsulated at a predetermined ratio in SLNs (PC-SLNs) with high encapsulation efficiency (CU: 97.6%, PTX: 95.8%), appropriate particle size (121.8 ± 1.69 nm), small PDI (0.267 ± 0.023), and negative zeta potential (-30.4 ± 1.25 mV). Compared with PTX or the combination of CU and PTX (CUþPTX), PC-SLNs can greatly reduce the dose of PTX while still achieving the same therapeutic effect on four cancer cell lines, among which the inhibitory effect on A549 lung cancer cells was the strongest. PCSLNs improved the area under the curve (CU: 1.40-fold; PTX: 2.88-fold), prolonged the residence time (CU: 6.94-fold; PTX: 2.51-fold), and increased the half-life (CU: 5.62-fold; PTX: 6.46-fold), achieving long circulation. PC-SLNs were used to treat lung cancer in a nude mouse xenograft tumor model and the tumor suppression rate reached 78.42%, while those of PTX and (CUþPTX) were 40.53% and 51.56%, respectively. As PC-SLNs can prevent P-glycoprotein efflux, reverse MDR and downregulate the NF-jB pathway. PC-SLNs are a potential antineoplastic agent that is more effective and less toxic in treating lung cancer. [ABSTRACT FROM AUTHOR]

Context: Curcumin (Cur) has a short duration of action which limits its therapeutic efficacy. Carbonic acid 17-(1,5-dimethyl-hexyl)-10,13-dimethyl-2,3,4,7,8,9,10,11,12,13,14,15,16,17-tetradecahydro-1H-cyclopenta[a]-phenanthren-3-yl ester 4-[7-(4-hydroxy-3-methoxy-phenyl)-3,5-dioxo-hepta-1,6-dienyl]-2-methoxy-phenyl ester (CUD), as a small molecule derivative of Cur with superior stability, has been developed in our laboratory. Objective: CUD-loaded solid lipid nanoparticles (CUD-SLN) were prepared to prolong the duration of the drug action of Cur. Materials and methods: CUD-SLN were prepared with Poloxamer 188 (F68) and hydrogenated soybean phospholipids (HSPC) as carriers, and the prescription was optimized. The in vitro release of CUD and CUD-SLN was investigated. CUD-SLN (5mg/kg) was injected into Sprague Dawley (SD) rats to investigate its pharmacokinetic behaviour. Results: CUD-SLN features high entrapment efficiency (96.8 ± 0.4%), uniform particle size (113.0 ± 0.8nm), polydispersity index (PDI) (0.177 ± 0.007) and an appropriate drug loading capacity (6.2 ± 0.1%). Optimized CUD-SLN exhibited sustained release of CUD for about 48 h. Moreover, the results of the pharmacokinetic studies showed that, compared to Cur, CUD-SLN had a considerably prolonged half-life of 14.7 h, slowed its metabolism in vivo by 35.6-fold, and had an improved area under the curve (AUC0-t) of 37.0-fold. Conclusions: CUD-SLN is a promising preparation for the development of a small molecule derivative of Cur. [ABSTRACT FROM AUTHOR]

The popularity of executive coaching has increased dramatically in both the practitioner world and academia during the past decade. However, evaluating the effectiveness of coaching has lagged behind. Executive coaching is a multidisciplinary practice, and professionals from many different scholarly backgrounds provide coaching services. The paucity of empirical research may be attributed to the lack of a consensus among these divergent professionals regarding whether and how to evaluate the effectiveness of coaching. In this article, we conducted a meta-analysis of the empirical research as well as reviewed the retrospective studies evaluating coaching effectiveness. Subsequently, we discussed six areas that impact the way researchers evaluate coaching effectiveness and the conclusions they may draw from their studies. Although the Return On Investment (ROI) index provides a straightforward, overall measure of effectiveness, its veracity and usefulness is questioned. It is hoped that the clarification of these areas will help guide the future of coaching evaluation research and practice. [ABSTRACT FROM AUTHOR]

Background: RX-0201 is an antisense oligonucleotide (ASO) against Akt1 currently in clinical trial for metastatic renal cancer. Purpose: To improve the delivery of RX-0201 using folate receptor-targeted lipid-albumin nanoparticles (F-LAN). Methods: F-LAN were synthesized with the composition of DOTAP/soyPC/TPGS/folate-PEG-DSPE (25:70:4:1 m/m), a cationic human serum albumin-pentaethylenehexamine (HSA-PEHA) conjugate and RX-0201. The nanoparticles were evaluated in KB human carcinoma cells in vitro and in a KB murine xenograft tumour model in vivo for pharmacokinetics and antitumor activities. Results: The F-LAN-RX-0201 had a mean particle size of 108.6 ± 5.8 nm, zeta potential of 10.5 ± 3.2 mV and ASO loading efficiency of 71.5 ± 4.5%. In KB cells, uptake and Akt1 inhibition by F-LAN-RX-0201 were greater than those of non-targeted LAN-RX-0201 and could be partially blocked by excess free folate. F-LAN-RX-0201 inhibited cell growth with an IC50 of 11.9 μM. In contrast, LAN-RX-0201 showed lower cytotoxicity with an IC50 of 32.0 μM. No significant cytotoxicity was observed with up to 250 µM of free RX-0201. Pharmacokinetic studies showed that F-LAN-RX-0201 had a longer terminal half-life than free RX-0201 (442 vs. 219 min). In a KB xenograft tumour model, F-LAN-RX-0201 exhibited greater tumour inhibition than LAN-RX-0201 at 16 mg/kg. Moreover, F-LAN-RX-0201 at 16 mg/kg showed comparable tumour inhibition compared to free RX-0201 at a much higher dose of 90 mg/kg. Conclusions: F-LAN-RX-0201 showed promise as a therapeutic agent for tumours with elevated folate-receptor expression. [ABSTRACT FROM AUTHOR]

The present systematic study focused to investigate the oleic acid derivative of branched polyethylenimine (bPEI-OA)-functionalized proliposomes for improving the oral delivery of extract ofGinkgo biloba(GbE). The GbE proliposomes were prepared by a spray drying method at varying ratios of egg yolk phosphatidylcholine and cholesterol, and the optimized formulation was tailored with bPEI-OA to obtain bPEI-OA-functionalized proliposomes. The formulations were characterized for particle size, zeta potential, and entrapment efficiency. The release of GbE from proliposomes exhibited a sustained release. And the release rate was regulated by changing the amount of bPEI-OA on the proliposomes. The physical state characterization studies showed some interactions between GbE and other materials, such as hydrogen bonds and van der Waals forces during the process of preparation of proliposomes. Thein situsingle-pass perfusion and oral bioavailability studies were performed in rats. The significant increase in absorption constant (Ka) and apparent permeability coefficient (Papp) from bPEI-OA-functionalized proliposomes indicated the importance of positive charge for effective uptake across the gastrointestinal tract. The oral bioavailability of bPEI-OA-functionalized proliposomes was remarkable enhanced in comparison with control and conventional proliposomes. The bPEI-OA-functionalized proliposomes showed great potential of improving oral absorption of GbE as a suitable carrier. [ABSTRACT FROM AUTHOR]

A new muscarinic receptor antagonist, 5-hydroxymethyl tolterodine (5-HMT), was successfully encapsulated into PLGA microspheres. With an increase of PLGA concentration from 15% to 40%, encapsulation efficiency of 5-HMT increased from 55.39% to 76.32%, and the particle size of microsphere increased from 34.33 to 70.48 µm. Increasing the homogenisation speed from 850 to 2300 rpm, the particle size was reduced about 65%.The in vitro and in vivo studies in beagle dogs show that the release profile of 5-HMT-loaded microspheres (5-HMT MS) prepared with 503H is characterised by a low initial burst followed by slow release that lasted for 2 weeks. A Cmax of 1.617 ± 0.392 ng/mL was found on the sixth day. When evaluated for inhibition of the carbachol-induced contraction of rat urinary bladder, 5-HMT MS showed a much longer and more potent effect than tolterodine tablets. The mean urination time of the rats in the 5-HMT MS group was significantly decreased ( p < 0.05 or p < 0.01) to less than 2 weeks. [ABSTRACT FROM AUTHOR]

Efficient and site-specific delivery of therapeutic drugs is a critical challenge in clinical treatment of cancer. Nano-sized carriers such as liposomes, micelles, and polymeric nanoparticles have been investigated for improving bioavailability and pharmacokinetic properties of therapeutics via various mechanisms, for example, the enhanced permeability and retention (EPR) effect. Further improvement can potentially be achieved by conjugation of targeting ligands onto nanocarriers to achieve selective delivery to the tumour cell or the tumour vasculature. Indeed, receptor-targeted nanocarrier delivery has been shown to improve therapeutic responses both in vitro and in vivo. A variety of ligands have been investigated including folate, transferrin, antibodies, peptides and aptamers. Multiple functionalities can be incorporated into the design of nanoparticles, e.g., to enable imaging and triggered intracellular drug release. In this review, we mainly focus on recent advances on the development of targeted nanocarriers and will introduce novel concepts such as multi-targeting and multi-functional nanoparticles. [ABSTRACT FROM AUTHOR]