Quantum fidelity of electromagnetically induced transparency: the full quantum theory.

We present a full quantum model to study the fidelity of single photons with different quantum states propagating in a medium exhibiting electromagnetically induced transparency (EIT). By using the general reservoir theory, we can calculate the quantum state of the transmitted probe photons that reveal the EIT phenomenon predicted by semiclassical theory while reflecting the influence of the quantum fluctuations of the strong coupling field. Our study shows that the coupling field fluctuations not only change the quantum state of the probe photons, but also slightly affect its transmittance. Moreover, we demonstrate that the squeezed coupling field can enhance the influence of its fluctuations on the quantum state of the probe photons, which means that the EIT effect can be manipulated by controlling the quantum state properties of the coupling field. The full quantum theory in this paper is suitable for studying quantum systems related to the EIT mechanism that would allow us to examine various quantum effects in EIT-based systems from a full quantum perspective.

The E3 ubiquitin ligase UBE3C enhances proteasome processivity by ubiquitinating partially proteolyzed substrates.

To maintain protein homeostasis, cells must balance protein synthesis with protein degradation. Accumulation of misfolded or partially degraded proteins can lead to the formation of pathological protein aggregates. Here we report the use of destabilizing domains, proteins whose folding state can be reversibly tuned using a high affinity ligand, as model substrates to interrogate cellular protein quality control mechanisms in mammalian cells using a forward genetic screen. Upon knockdown of UBE3C, an E3 ubiquitin ligase, a reporter protein consisting of a destabilizing domain fused to GFP is degraded more slowly and incompletely by the proteasome. Partial proteolysis is also observed when UBE3C is present but cannot ubiquitinate substrates because its active site has been mutated, it is unable to bind to the proteasome, or the substrate lacks lysine residues. UBE3C knockdown also results in less substrate polyubiquitination. Finally, knockdown renders cells more susceptible to the Hsp90 inhibitor 17-AAG, suggesting that UBE3C protects against the harmful accumulation of protein fragments arising from incompletely degraded proteasome substrates.

Small-molecule displacement of a cryptic degron causes conditional protein degradation.

The ability to rapidly regulate the functions of specific proteins in living cells is a valuable tool for biological research. Here we describe a new technique by which the degradation of a specific protein is induced by a small molecule. A protein of interest is fused to a ligand-induced degradation (LID) domain, resulting in the expression of a stable and functional fusion protein. The LID domain is comprised of the FK506- and rapamycin-binding protein (FKBP) and a 19-amino-acid degron fused to the C terminus of FKBP. In the absence of the small molecule Shield-1, the degron is bound to the FKBP fusion protein and the protein is stable. When present, Shield-1 binds tightly to FKBP, displacing the degron and inducing rapid and processive degradation of the LID domain and any fused partner protein. Structure-function studies of the 19-residue peptide showed that a 4-amino-acid sequence within the peptide is responsible for degradation.

Development of a Swellable and Floating Gastroretentive Drug Delivery System (sfGRDDS) of Ciprofloxacin Hydrochloride.

Sangelose® (SGL) is a novel hydroxypropyl methylcellulose (HPMC) derivative that has been hydrophobically modified. Due to its high viscosity, SGL has the potential as a gel-forming and release-rate-controlled material for application in swellable and floating gastroretentive drug delivery systems (sfGRDDS). The aim of this study was to develop ciprofloxacin (CIP)-loaded sfGRDDS tablets comprised of SGL and HPMC in order to extend CIP exposure in the body and achieve optimal antibiotic treatment regimes. Results illustrated that SGL-HPMC-based sfGRDDS could swell to a diameter above 11 mm and showed a short floating lag time (<4 s) and long total floating time (>24 h) to prevent gastric emptying. In dissolution studies, CIP-loaded SGL-HPMC sfGRDDS demonstrated a specific biphasic release effect. Among the formulations, the SGL/type-K HPMC 15,000 cps (HPMC 15K) (50:50) group exhibited typical biphasic release profiles, with F4-CIP and F10-CIP individually releasing 72.36% and 64.14% CIP within 2 h dissolution, and sustaining release to 12 h. In pharmacokinetic studies, the SGL-HPMC-based sfGRDDS demonstrated higher Cmax (1.56-1.73 fold) and shorter Tmax (0.67 fold) than HPMC-based sfGRDDS. Furthermore, SGL 90L in GRDDS indicated an excellent biphasic release effect and a maximum elevation of relative bioavailability (3.87 fold). This study successfully combined SGL and HPMC to manufacture sfGRDDS that retain CIP in the stomach for an optimal duration while improving its pharmacokinetic characteristics. It was concluded that the SGL-HPMC-based sfGRDDS is a promising biphasic antibiotic delivery system that can both rapidly achieve the therapeutic antibiotic concentration and maintain the plasma antibiotic concentration for an extended period to maximize antibiotic exposure in the body.

Composite Hydrogels of Ultrasound-Assisted-Digested Formic Acid-Decellularized Extracellular Matrix and Sacchachitin Nanofibers Incorporated with Platelet-Rich Plasma for Diabetic Wound Treatment.

In this study, an ultrasound-assisted digestion method of a formic acid-decellularized extracellular matrix (dECM) of porcine skin was developed and optimized to form UdECM hydrogels for diabetic wound healing. Results demonstrated that ultrasonication improved the extraction rate of collagen from dECM samples, preserved the collagen content of dECM, reduced residual cells, and extracted greater DNA contents. Scanning electron microscope (SEM) analyses were performed, which demonstrated the optimal porosity on the surface and density of the cross-section in the hydrogel structure, which could control the release of growth factors embedded in UdECM hydrogels at desirable rates to boost wound healing. A wound-healing study was conducted with six different composite hydrogels, both empty materials and materials enriched with rat platelet-rich plasma (R-PRP), sacchachitin nanofibers (SCNFs), and TEMPO-oxidized sacchachitin in diabetic rats. The assessment based on scars stained with hematoxylin and eosin (H&E), Masson's trichrome (MT), and a cluster of differentiation 31 (CD31) staining showed that the UdECM/SC/R-PRP treatment group had the most significant efficacy of promoting healing and even recovery of diabetic wounds to normal tissues. UdECM/R-PRP and UdECM/SCNFs demonstrated better healing rates than UdECM hydrogel scaffolds, which had only recovered 50% resemblance to normal skin. Treatment with both UdECM/TEMPO 050 and UdECM/TEMPO 050/R-PRP hydrogel scaffolds was ranked last, with even poorer efficacy than UdECM hydrogels. In summary, formulated UdECM and SCNF hydrogels loaded with PRP showed synergistic effects of accelerating wound healing and ultimately stimulating the wound to recover as functional tissues. This newly UdECM/SCNF composite hydrogel has promising potential for healing and regenerating diabetic wounds.

Oral metronomic therapy of pancreatic cancer with gemcitabine and paclitaxel co-loaded in lecithin-based Self-Nanoemulsifying preconcentrate (LBSNEP).

This study aimed to evaluate gemcitabine (GEM)/paclitaxel (PTX) co-loaded into a lecithin-based self-nanoemulsifying preconcentrate (LBSNEP) orally administered in a metronomic therapeutic manner against pancreatic cancer. LBSNEP was developed and evaluated, composed of Caproyl 90, Tween80, lecithin, TPGS, and propyl glycol at a ratio of 20:20:30:5:25, resulting in a droplet diameter of approximately 180 nm. Cell viability studies on MIA PaCa-2 demonstrated a synergetic effect at a proportion of 1:2 between PTX and GEM. Additionally, LBSNEP and baicalein (BAI) were demonstrated to prevent GEM from being deaminated by cytidine deaminase. The combination of GEM, PTX, and BAI in the LBSNEP showed good dissolution in simulated gastric fluid. The pharmacokinetic study conducted on rats showed that co-administration of GEM, PTX, and BAI in the LBSNEP enhanced the respective relative oral bioavailability levels of GEM and PTX by 1.5- and 2-fold, respectively, compared to the solution group. The tumor inhibition study was conducted with metronomic therapy at a low daily dose compared to conventional therapy at a higher dose every 3 days. Results indicated that oral metronomic delivery of GEM/PTX/BAI LBSNEP could inhibit tumor growth during administration phase, and that there were similar tumor volumes compared to traditional chemotherapy at day 28 even if the dose of metronomic chemotherapy was 2.2-fold less than that of the latter. In conclusion, a self-nanoemulsifying drug-delivery system for the oral delivery of GEM, PTX, and BAI in a metronomic manner enhanced the therapeutic effect on pancreatic cancer, providing an alternative option for chemotherapy.

Poloxamer sols endowed with in-situ gelability and mucoadhesion by adding hypromellose and hyaluronan for prolonging corneal retention and drug delivery.

The purpose of this study was to develop poloxamer (P407)-based in-situ thermogellable hydrogels with reducing concentration of P407 by adding hypromellose (HPMC) and with enhancing mucoadhesion of resulting hydrogels by adding hyaluronic acid (HA) for prolonging ocular delivery of hydroxypropyl-ß-cyclodextrin (HPßCD)-solubilized testosterone (TES). Results demonstrated that 0.5% TES solution was successfully solubilized with adding 10% HPßCD. Non-gellable 13% P407 sol became in-situ gellable with adding 2.0-2.5% HPMC and mucoadhesibility was further imporved with adding 0.3% HA-L (low MW) or HA-H (high MW). Optimized 0.5% HPßCD-solubilized TES P407-based thermogellable hydrogels with enhancement of mucoadhesion for prolonging ocular delivery comprised 13% P407, 2.5% HPMC, and 0.3% HA-L or HA-H. Furthermore, rheological measurements under simulated eye blinking confirmed that non-thixotropic properties of optimized hydrogels could be spreaded evenly and retain a greater amount of drug-loaded hydrogels on the ocular surface for a longer period to prolong drug delivery. Compared with conventional eye drops, the prolonged residence time of optimized hydrogels from ex vivo and in vivo studies were observed, indicating relationships between rheological properties and in vivo performances. It was concluded that P407-based thermosensitive hydrogels with reducing concentration of P407 and enhancing mucoadhesion was successfully formulated by adding 2.5% HPMC and 0.3% HA in 13% P407 for potentially accomplishing effective clinical treatment of DED.

Synergistic Combination of Irinotecan and Rapamycin Orally Delivered by Nanoemulsion for Enhancing Therapeutic Efficacy of Pancreatic Cancer.

In recent years, combining different types of therapy has emerged as an advanced strategy for cancer treatment. In these combination therapies, oral delivery of anticancer drugs is more convenient and compliant. This study developed an irinotecan/rapamycin-loaded oral lecithin-based self-nanoemulsifying nanoemulsion preconcentrate (LBSNENPir/ra) and evaluated its synergistic combination effects on pancreatic cancer. LBSNENP loaded with irinotecan and rapamycin at a ratio of 1:1 (LBSNENPir10/ra10) had a better drug release profile and smaller particle size (<200 nm) than the drug powder. Moreover, LBSNENPir10/ra10 exhibited a strong synergistic effect (combination index [CI] < 1.0) in cell viability and combination effect studies. In the tumor inhibition study, the antitumor activity of LBSNENPir10/ra10/sily20 against MIA PaCa-2 (a human pancreatic cancer cell line) was significantly increased compared with the other groups. When administered with rapamycin and silymarin, the area under the curve and the maximum concentration of irinotecan significantly improved compared with the control. We successfully developed an irinotecan/rapamycin-loaded oral self-nanoemulsifying nanoemulsion system to achieve treatment efficacy for pancreatic cancer.

Destabilizing domains derived from the human estrogen receptor.

Methods to rapidly and reversibly perturb the functions of specific proteins are desirable tools for studies of complex biological processes. We have demonstrated an experimental strategy to regulate the intracellular concentration of any protein of interest by using an engineered destabilizing protein domain and a cell-permeable small molecule. Destabilizing domains have general utility to confer instability to a wide range of proteins including integral transmembrane proteins. This study reports a destabilizing domain system based on the ligand binding domain of the estrogen receptor that can be regulated by one of two synthetic ligands, CMP8 or 4-hydroxytamoxifen.

A cAMP Sensor Based on Ligand-Dependent Protein Stabilization.

cAMP is a ubiquitous second messenger with many functions in diverse organisms. Current cAMP sensors, including Föster resonance energy transfer (FRET)-based and single-wavelength-based sensors, allow for real time visualization of this small molecule in cultured cells and in some cases in vivo. Nonetheless the observation of cAMP in living animals is still difficult, typically requiring specialized microscopes and ex vivo tissue processing. Here we used ligand-dependent protein stabilization to create a new cAMP sensor. This sensor allows specific and sensitive detection of cAMP in living zebrafish embryos, which may enable new understanding of the functions of cAMP in living vertebrates.

Combined Docetaxel/Pictilisib-Loaded mPEGylated Nanocarriers with Dual HER2 Targeting Antibodies for Synergistic Chemotherapy of Breast Cancer.

Introduction: Approximately 15%~30% of breast cancers have gene amplification or overexpression of the human epidermal growth factor receptor 2 (HER2), resulting in the chemotherapy resistance, a more-aggressive phenotype and poor prognosis. Methods: We propose a strategy of nanocarriers co-loaded with docetaxel (DTX) and pictilisib (PIC) at a synergistic ratio and non-covalently bound with dual anti-HER2 epitopes bispecific antibodies (BsAbs: anti-HER2-IV/methoxy-polyethylene glycol (mPEG) and anti-HER2-II/methoxy-PEG) for synergistic targeting to overcome the therapeutic dilemmas of the resistance for HER2-targetable chemodrugs. DTX/PIC-loaded nanocarriers (D/P_NCs) were prepared with single emulsion methods and characterized using dynamic light scattering analysis, and the drug content was assayed by high-performance liquid chromatographic method. The integrity and function of BsABs were evaluated using sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS-PAGE) and enzyme-linked immunosorbent assay (ELISA). The in vitro cell studies and in vivo breast tumor-bearing mice model were used to evaluate the anti-cancer effect and biosafety of formulations. Results: D/P_NCs optimally prepared exhibited a spherical morphology with small particle sizes (~140 nm), high drug loading (~5.5%), and good colloidal stability. The synergistic tumor cytotoxicity of loading DTX and PIC at 2:1 ratio in D/P_NCs was discovered. The BsAbs are successfully decorated on mPEGylated DTX/PIC-loaded nanocarriers via anti-mPEG moiety. In vitro studies revealed that non-covalent decoration with dual BsAbs on D_P-NCs significantly and synergistically increased cellular uptake, while with loading DTX and PIC at a synergistic ratio of 2:1 in D/P_NCs further resulted in synergistic cytotoxicity. In vivo tumor inhibition studies showed the comparable results for synergistic antitumor efficacy while minimizing systemic toxicity of chemodrugs. Conclusion: Non-covalent modification with dual distinct epitopes BsAbs on the nanocarriers loaded with dual chemodrugs at a synergistic ratio was expected to be a promising therapeutic platform to overcome the chemoresistance of various cancers and warrants further development for future therapy in the clinical.

Honokiol/Magnolol-Loaded Self-Assembling Lecithin-Based Mixed Polymeric Micelles (lbMPMs) for Improving Solubility to Enhance Oral Bioavailability.

OBJECTIVE: This study was intended to utilize lecithin-based mixed polymeric micelles (lbMPMs) for enhancing the solubility and bioavailability of honokiol and magnolol to resolve the hindrance of their extreme hydrophobicity on the clinical applications. METHODS: Lecithin was selected to increase the volume of the core of lbMPMs, thereby providing a greater solubilization capacity. A series of amphiphilic polymers (sodium deoxycholate [NaDOC], Cremophor®, and Pluronic® series) were included with lecithin for screening and optimization. RESULTS: After preliminary evaluation and subsequentially optimization, two lbMPMs formulations composed of honokiol/magnolol:lecithin:NaDOC (lbMPMs[NaDOC]) and honokiol/magnolol:lecithin:PP123 (lbMPMs[PP123]) in respective ratios of 6:2:5 and 1:1:10 were optimally obtained with the mean particle sizes of 80-150 nm, encapsulation efficacy (EEs) of >90%, and drug loading (DL) of >9.0%. These lbMPMs efficiently stabilized honokiol/magnolol in phosphate-buffered saline (PBS) at room temperature or 4 °C and in fetal bovine serum or PBS at 37 °C. PK study demonstrated that lbMPMs[NaDOC] showed much improvement in enhancing bioavailability than that by lbMPMs[PP123] for both honokiol and magnolol. The absolute bioavailability for honokiol and magnolol after intravenous administration of lbMPMs[NaDOC] exhibited 0.93- and 3.4-fold increases, respectively, compared to that of free honokiol and magnolol. For oral administration with lbMPMs[NaDOC], the absolute bioavailability of honokiol was 4.8%, and the absolute and relative bioavailability of magnolol were 20.1% and 2.9-fold increase, respectively. CONCLUSION: Overall, honokiol/magnolol loaded in lbMPMs[NaDOC] showed an improvement of solubility with suitable physical characteristics leading to enhance honokiol and magnolol bioavailability and facilitating their wider application as therapeutic agents for treating human disorders.

Fabrication and characterization of Rhizochitosan and its incorporation with platelet concentrates to promote wound healing.

Composite dressing composed of Rhizochitosan and Regenplex™ to promote wound healing were assessed. Rhizochitosan was fabricated by deacetylation of Rhizochitin, which obtained by simply depigmenting sporangium-free mycelial mattress produced from Rhizopus stolonifer F6. Physicochemical characterizations of Rhizochitosan demonstrated that it contained 13.5% chitosan with a water-absorption ability of 35-fold dry weight and exhibiting hydrogel nature after hydration. In a wound-healing study on SD rats with full-thickness injury, the composite dressing had a better healing effect than those for each individual components and control group and wound even healed as functional tissue instead of scar tissue. The underlying mechanism of the composite beneficial to wound remodeling is likely attributable to a more reduction level of matrix metalloproteinase (MMP)-9 expression in early stage and a higher MMP-2 expression level in a later stage of healing process. Conclusively, the composite dressing demonstrated to be highly beneficial to the healing of full-thickness injury wound.

CPT11 with P-glycoprotein/CYP 3A4 dual-function inhibitor by self-nanoemulsifying nanoemulsion combined with gastroretentive technology to enhance the oral bioavailability and therapeutic efficacy against pancreatic adenocarcinomas.

Therapeutic efficacies of orally administrated hydrophobic chemodrugs are decreased by poor water solubilities and reduced oral bioavailabilities by P-glycoprotein (P-gp) and CYP450. In this study, CPT11 alone or combined with dual-function inhibitors (baicalein (BA) silymarin (SM), glycyrrhizic acid (GA), and glycyrrhetinic acid (GLA)) of P-gp and CYP450 loaded in a lecithin-based self-nanoemulsifying nanoemulsion preconcentrate (LBSNENP) to improve the solubility and inhibit the elimination by P-gp and CYP450. Results revealed that the LBSNENP composed of Capryol 90, lecithin/Tween 80/Cremophor EL, and propylene glycol at a weight ratio of 18:58:24 (designated PC90C10P0) was optimally selected. Encapsulating CPT11 with PEO-7000K in PC90C10P10/30 further enhanced the resultant hydrogel to be gastro-retainable and to release CPT11 in a sustained manner. Pharmacokinetic study of CPT11-loaded PC90C10P0 administered orally revealed an absolute bioavailability (FAB, vs. intravenous CPT11) of 7.8 ± 1.01% and a relative bioavailability (FRB1, vs. oral solution of CPT11) of 70.7 ± 8.6% with a longer half-life (T1/2) and mean residence time (MRT). Among the dual-function inhibitors, SM was shown to be the most influential in increasing the oral bioavailability of CPT11. SM also increased the plasma concentration of the SN-38 active metabolite, which formed from the enhanced plasma concentration of CPT11. It is concluded that treatment with CPT11 loaded in PC90C10P0 with or without solubilization with SM could expose tumors to higher plasma concentrations of both CPT11 and SN-38 leading to enhancement of tumor growth inhibition with no signs of adverse effects.

Carfilzomib and Paclitaxel Co-Loaded Protein Nanoparticles an Effective Therapy Against Pancreatic Adenocarcinomas.

PURPOSE: Therapeutic efficacy of pancreatic adenocarcinomas (PACs) with combined therapy of carfilzomib (CFZ) and paclitaxel (PTX) co-loaded in human serum albumin (HSA) nanoparticles (NPs) was examined. METHODS: CFZ and PTX were encapsulated individually or combined into HSA NPs by a simple reverse self-assembly method developed to achieve an optimal combination ratio for synergistic therapy. CFZ or/and PTX loaded HSA nanoparticles were physically characterized and the evaluation of combination index, drug release, pharmacokinetic, anti-tumor, and biodistribution studies were conducted. RESULTS: All resultant drug-loaded HSA NPs were spherical with a particle size of <150 nm and a zeta potential of -21.1~-23.0 mV. Drug loading rates and entrapment efficiencies were 9.1%~10.1% and 90.7%~97.1%, respectively. CFZ and PTX demonstrated synergistic effects in an MIA PaCa-2 cytotoxicity at a 1:2 ratio (CI50 were 0.01~0.25). In vitro dissolution revealed that the CFZ/PTX ratio released from the co-loaded HSA NPs (CFZ/PTX/HSA NPs) was about 1.77~2.08, which conformed to the designated loaded ratio. In vivo evaluation showed that the combined therapy of CFZ and PTX at a 1:2 ratio co-loaded in HSA NPs (CFZ/PTX/HSA NPs) demonstrated optimal synergistic improvement of the growth inhibition of MIA PaCa-2 cells with less systematic toxicity, even though the pharmacokinetic profiles observed did not show obvious beneficial and their biodistributions in tumors were found to be smaller. CONCLUSION: The one-pot reverse assembly method developed was environmentally friendly and capable of co-loading an optimal combination ratio of two chemodrugs into HSA NPs for synergistic therapy.

Active Tumoral/Tumor Environmental Dual-Targeting by Non-Covalently Arming with Trispecific Antibodies or Dual-Bispecific Antibodies on Docetaxel-Loaded mPEGylated Nanocarriers to Enhance Chemotherapeutic Efficacy and Minimize Systemic Toxicity.

PURPOSE: This study was aimed at developing the trispecific antibodies (anti-EGFR/anti-FAP/anti-mPEG, TsAb) or dual bispecific antibodies (anti-EGFR/anti-mPEG and anti-FAP/anti-mPEG) docetaxel (DTX)-loaded mPEGylated lecithin-stabilized micelles (mPEG-lsbPMs) for improving the targeting efficiency and therapeutic efficacy. METHODS: mPEG-lsbPMs were simply prepared via thin film method. The trispecific antibodies or bispecific antibodies bound the mPEG-lsbPMs by anti-mPEG Fab fragment. The formulations were characterized by DLS and TEM; in vitro and in vivo studies were also conducted to evaluate the cellular uptake, cell cytotoxicity and therapeutic efficacy. RESULTS: The particle sizes of mPEG-lsbPMs with or without the antibodies were around 100 nm; the formulations showed high encapsulation efficiencies of 97.12%. The TsAb and dual bispecific antibodies were fabricated and demonstrated their targeting ability. Two EGFR-overexpressed cell lines (HT-29 and MIA PaCa-2) were co-cultured with FAP-overexpressed WS1 cells (HT-29/WS1; MIA PaCa-2/WS1) to mimic a tumor coexisting in the tumor microenvironment. Cellular binding study revealed that the binding of anti-FAP micelles to three co-culture ratios (4:1, 1:1, and 1:4) of HT-29/EGFR to WS1/FAP was significantly higher than that for TsAb micelles and dual (1:1) micelles, and the binding of those targeting antibodies to WS1/FAP and MIA PaCa-2/EGFR was equally efficacious resulting in a similar binding amount of the TsAb and dual BsAbs (1:1) with the co-culture of MIA PaCa-2/EGFR and WS1/FAP at a 1:1 ratio. Antitumor efficacy study showed that treatment with DTX-loaded mPEG-lsbPMs modified with or without BsAbs, dual BsAbs (1:1), and TsAbs was enhanced in inhibiting tumor growth compared with that for Tynen® while showing fewer signs of adverse effects. CONCLUSION: Active targeting of both tumors and TAF-specific antigens was able to increase the affinity of DTX-loaded mPEG-lsbPMs toward tumor cells and TAFs leading to successive uptake by tumor cells or TAFs which enhanced their chemotherapeutic efficacy against antigen-positive cancer cells.

One-pot fabrication of sacchachitin for production of TEMPO-oxidized sacchachitin nanofibers (TOSCNFs) utilized as scaffolds to enhance bone regeneration.

One-pot fabrication of sacchachitin (SC) for mass-production was developed and optimized by selecting KOH as alkaline agent in depigmentation step and utilizing NaClO2 as bleaching agent in subsequent step in the same pot. Overall yield of one-pot-fabricated SC was up to 35 %w/w of initial weight with a fibrous texture soft enough for mechanical disintegration into SC nanofibers (SCNFs) and better dispersion for producing TEMPO-oxidized SCNFs (T033SC). Both SCNFs and T033SC could form a 3D gelatinous scaffold into which MC3T3-E1 cells were attracted. Higher calcium-trapping ability of T033SC resulting from a greater extent of carboxylate groups provided an excellent bone regeneration environment that resulted in better outcomes of bone regeneration in a femur defect rat model compared to those with SCNFs possessed fewer carboxylate groups. In conclusion, biomaterial scaffolds based on TEMPO-oxidized SCNFs produced from one-pot fabricated SC showed great potential for bone regeneration due to unique physical and chemical properties.

Transient rest restores functionality in exhausted CAR-T cells through epigenetic remodeling.

T cell exhaustion limits immune responses against cancer and is a major cause of resistance to chimeric antigen receptor (CAR)-T cell therapeutics. Using murine xenograft models and an in vitro model wherein tonic CAR signaling induces hallmark features of exhaustion, we tested the effect of transient cessation of receptor signaling, or rest, on the development and maintenance of exhaustion. Induction of rest through enforced down-regulation of the CAR protein using a drug-regulatable system or treatment with the multikinase inhibitor dasatinib resulted in the acquisition of a memory-like phenotype, global transcriptional and epigenetic reprogramming, and restored antitumor functionality in exhausted CAR-T cells. This work demonstrates that rest can enhance CAR-T cell efficacy by preventing or reversing exhaustion, and it challenges the notion that exhaustion is an epigenetically fixed state.

A Method for Conditional Regulation of Protein Stability in Native or Near-Native Form.

Here, we report a method to regulate cellular protein levels by introducing a ubiquitin variant between a destabilizing domain (DD) and the regulated protein. When produced in the absence of a stabilizing ligand the DD dominates and the entire fusion protein is processively degraded by the proteasome. In the presence of the stabilizing ligand the fusion protein is metabolically stable and becomes a substrate for abundant ubiquitin-specific proteases, liberating a native, or a near-native protein-of-interest. This technique is thus particularly useful for the study of proteins whose free N terminus is required for proper function. In addition, removal of the DD in the presence of stabilizing ligand leads to higher expression levels of regulated protein when cells experience transient exposure to a stabilizing ligand, such as in a living animal receiving a single dose of a pharmacological agent as the stabilizing ligand.

Preparation and Characterization of a Novel Swellable and Floating Gastroretentive Drug Delivery System (sfGRDDS) for Enhanced Oral Bioavailability of Nilotinib.

Regarding compliance and minimization of side effects of nilotinib therapy, there is a medical need to have a gastroretentive drug delivery system (GRDDS) to enhance the oral bioavailability that is able to administer an optimal dose in a quaque die (QD) or daily manner. In this study, the influence on a swelling and floating (sf) GRDDS composed of a polymeric excipient (HPMC 90SH 100K, HEC 250HHX, or PEO 7000K) and Kollidon® SR was examined. Results demonstrated that PEO 7000K/Kollidon SR (P/K) at a 7/3 ratio was determined to be a basic GRDDS formulation with optimal swelling and floating abilities. MCC PH102 or HPCsssl,SFP was further added at a 50% content to this basic formulation to increase the tablet hardness and release all of the drug within 24 h. Also, the caplet form and capsule form containing the same formulation demonstrated higher hardness for the former and enhanced floating ability for the latter. A pharmacokinetic study on rabbits with pH values in stomach and intestine similar to human confirmed that the enhanced oral bioavailability ranged from 2.65-8.39-fold with respect to Tasigna, a commercially available form of nilotinib. In conclusion, the multiple of enhancement of the oral bioavailability of nilotinib with sfGRDDS could offer a pharmacokinetic profile with therapeutic effectiveness for the QD administration of a reasonable dose of nilotinib, thereby increasing compliance and minimizing side effects.