The effect of supplementing the calcium phosphate cement containing poloxamer 407 on cellular activities.

Calcium phosphate cement (CPC) is generally used for bone repair and augmentation. Poloxamers are tri-block copolymers that are used as surfactants but have applications in drug and antibiotic delivery. However, their biological effects on bone regeneration systems remain unelucidated. Here, we aimed to understand how supplementing the prototype CPC with poloxamer would impact cellular activity and its function as a bone-grafting material. A novel CPC, modified beta-tricalcium phosphate (mß-TCP) powder, was developed through a planetary ball-milling process using a beta-tricalcium phosphate (ß-TCP). The mß-TCP dissolves rapidly and accelerates hydroxyapatite precipitation; successfully shortening the cement setting time and enhancing the strength. Furthermore, the addition of poloxamer 407 to mß-TCP could reduce the risk of leakage from bone defects and improve fracture toughness while maintaining mechanical properties. In this study, the poloxamer addition effects (0.05 and 0.1 g/mL) on the cellular activities of MC3T3-E1 cells cultured in vitro were investigated. The cell viability of mß-TCP containing poloxamer 407 was similar to that of mß-TCP. All specimens showed effective cell attachment and healthy polygonal extension of the cytoplasm firmly attached to hydroxyapatite (HA) crystals. Therefore, even with the addition of poloxamer to mß-TCP, it does not have a negative effect to osteoblast growth. These data demonstrated that the addition of poloxamer 407 to mß-TCP might be considered a potential therapeutic application for the repair and regeneration of bone defects.

Lidocaine-loaded reduced graphene oxide hydrogel for prolongation of effects of local anesthesia: In vitro and in vivo analyses.

Lidocaine is widely used as a local anesthetic for alleviation of post-operative pain and for management of acute and chronic painful conditions. Although several approaches are currently used to prolong the duration of action, an effective strategy to achieve neural blockage for several hours remains to be identified. In this study, a lidocaine-loaded Pluronic® F68-reduced graphene oxide hydrogel was developed to achieve sustained release of lidocaine. Fourier transform infrared spectroscopy, X-ray diffraction, and Raman spectroscopy confirmed the synthesis of Pluronic® F68-reduced graphene oxide. Transmission electron microscopy showed wrinkled, flat nanosheets with micelles attached. The developed hydrogel showed desirable pH, viscosity, adhesiveness, hardness, and cohesiveness for topical application. The ex vivo release study demonstrated the ability of the Pluronic® F68-reduced graphene oxide hydrogel to prolong release up to 10 h, owing to the strong π-π interactions between the graphene oxide and the lidocaine. In comparison with a commercial lidocaine ointment, the developed graphene oxide hydrogel showed sustained anesthetic effect in the radiant heat tail flick test and sciatic nerve block model. Thus, this study demonstrates the potential of using Pluronic® F68-reduced graphene oxide nanocarriers to realize prolonged effects of local anesthesia for effective pain management.

Establishment and optimization of a hemp (Cannabis sativa L.) agroinfiltration system for gene expression and silencing studies.

Industrial hemp (Cannabis sativa L.) is a high-yielding annual crop primarily grown for fiber, seeds, and oil. Due to the phytochemical composition of hemp, there has been an increased interest in the market for nutraceuticals and dietary supplements for human health. Recent omics analysis has led to the elucidation of hemp candidate genes involved in the syntheses of specialized metabolites. However, a detailed study of these genes has not been undertaken due to the lack of a stable transformation system. We report for the first time an agroinfiltration system in hemp utilizing vacuum infiltration, which is an alternative method to stable transformation. A combination of 0.015% Silwett L-77, 5 mM ascorbic acid, and thirty second sonication followed by a 10-minute vacuum treatment resulted in the highest ß-glucuronidase expression in the leaf, male and female flowers, stem, and root tissues. The phytoene desaturase gene was silenced with a transient hairpin RNA expression, resulting in an albino phenotype in the leaves and the male and female flowers. This agroinfiltration system would be useful for overexpression and silencing studies of target genes to regulate the yield of specialized metabolites in hemp.

Pluronic-based graphene oxide-methylene blue nanocomposite for photodynamic/photothermal combined therapy of cancer cells.

A nanocomposite containing methylene blue (MB), graphene oxide (GO) and Pluronic F127 (PF127) had been developed for combined photothermal therapy (PTT) and photodynamic therapy (PDT). In this study, GO was firstly loaded with MB to form GO-MB by a self-assembly method, and then the surface was modified with PF127 to form GO-MB/PF127 nanocomposite (GO-MB/PF127) by a thin-film hydration method. The structure and properties of the nanocomposite were characterized by Ultraviolet-Visible spectroscopy (UV-vis), Fourier transform infrared spectroscopy (FT-IR), Raman spectroscopy, transmission electron microscope (TEM), dynamic light scattering (DLS) and zeta potential. The results showed that the as-prepared nanocomposite exhibited high stability in aqueous solution, high release rate of MB from the nanocomposite under acidic conditions. In addition, when excited by 808 nm near infrared (NIR) light and 660 nm light emitting diode (LED) source, GO in GO-MB/PF127 caused photothermal ablation of cancer cells while MB produced singlet oxygen (1O2) to kill cancer cells through oxidative stress in PDT. The combined therapy had a synergistic effect and can achieve a strong killing effect on SiHa cells at a low dose of GO-MB/PF127 containing GO (10 µg mL-1) and MB (5 µg mL-1). And PF127 did not affect the photothermal heating of GO and the 1O2 generation of MB. Moreover, light-induced GO-MB/PF127 nanocomposite killed SiHa cells by apoptosis pathway. The results indicated that the nanocomposite had the potential to effectively treat cancer via noninvasive phototherapy, and could be served as a multifunctional therapeutic agent for photodynamic/photothermal cancer therapy.

Multifunctional graphene-based magnetic nanocarriers for combined hyperthermia and dual stimuli-responsive drug delivery.

The synthesis of hydrophilic graphene-based yolk-shell magnetic nanoparticles functionalized with copolymer pluronic F-127 (GYSMNP@PF127) is herein reported to achieve an efficient multifunctional biomedical system for mild hyperthermia and stimuli-responsive drug delivery. In vitro tests revealed the extraordinary ability of GYSMNP@PF127 to act as smart stimuli-responsive multifunctional nanomedicine platform for cancer therapy, exhibiting (i) an outstanding loading capacity of 91% (w/w, representing 910 µg mg-1) of the chemotherapeutic drug doxorubicin, (ii) a high heating efficiency under an alternating (AC) magnetic field (intrinsic power loss ranging from 2.1-2.7 nHm2 kg-1), and (iii) a dual pH and thermal stimuli-responsive drug controlled release (46% at acidic tumour pH vs 7% at physiological pH) under AC magnetic field, in just 30 min. Additionally, GYSMNP@PF127 presents optimal hydrodynamic diameter (DH = 180 nm) with negative surface charge, high haemocompatibility for blood stream applications and tumour cellular uptake of drug nanocarriers. Due to its physicochemical, magnetic and biocompatibility properties, the developed graphene-based magnetic nanocarrier shows high promise as dual exogenous (AC field)/endogenous (pH) stimuli-responsive actuators for targeted thermo-chemotherapy, combining magnetic hyperthermia and controlled drug release triggered by the abnormal tumour environment. The presented strategy and findings can represent a new way to design and develop highly stable added-value graphene-based nanostructures for the combined treatment of cancer.

Pluronic lecithin organogel of 5-aminosalicylic acid for wound healing.

5-Aminosalicylic acid (5-ASA) is an aminosalicylate anti-inflammatory drug, which is also known as mesalazine or mesalamine. Currently employed in treating inflammatory bowel disease, ulcerative colitis, inflamed anus or rectum, and maintain remission in Crohn's disease. Evidence from the researchers highlighted its significant re-epithelization in allergic asthma, aphthous, and gastric ulcerative conditions. The objective of the study was to formulate the pluronic lecithin organogel (PLO) containing 5-ASA and evaluate its wound-healing ability in a full thickness excision wound rat model. The data obtained from in silico docking studies revealed 5-ASA is having an affinity towards the transforming growth factor-beta (TGF-ß) specifically towards beta1. Among various formulations prepared (F1 to F8), F1, and F6 have shown a maximum in vitro drug release with optimum pH and viscosity. From MTT assay it was found that selected PLO formulations showed no toxicity and enhanced cell proliferation in HaCaT cell lines. In vivo wound-healing studies in albino Wistar rats has revealed that PLO accelerates wound closure and reepithelization to the statistically significant level on day 3 (p < .05) in comparison with untreated wounds. In conclusion, the overall results suggest that 5-ASA PLO gel is a potential therapeutic option for the treatments of wounds, however, further studies are highly warrened to determine the various mechanisms of 5-ASA in regulating the cell migration and reepithelization in wound healing to outspread its use in clinics.

Enhanced oral bioavailability of an antipsychotic drug through nanostructured lipid carriers.

Olanzapine is an atypical antipsychotic, undergoes extensive first pass metabolism, also has poor aqueous solubility and belongs to BCS (Biopharmaceutical Classification System) Class II drug) exhibit low oral bioavailability. To overcome this and to enhance the bioavailability, intestinal lymphatic transport of drugs can be exploited through Nano structured lipid carriers (NLCs). The NLCs were formulated by solvent diffusion method using solid lipid (glyceryl tripalmitate), liquid lipid (castor oil) and surfactants (Pluronic F-68, Soylecithin). The formulated NLCs were characterized for physico-chemical properties, in-vitro release studies and in-vivo oral bioavailability. F6 has shown average particle size of 158.5 nm with PI of 0.115 indicating narrow particle size distribution and follows uni modal distribution. It was found that the batch with stearyl amine has a zeta potential of 28.39 mV which confers stability to the dispersion. Bioavailability studies indicate that there was more than 5½-fold increase in oral bioavailability in case of NLCs (F6) compared to olanzapine suspension which indicates that NLCs provided sustained release of the drugs, and these systems can be the preferred as drug carriers for lipophilic drugs in long term disease conditions such as schizophrenia for enhanced bioavailability.

Multifunctional theranostic Pluronic mixed micelles improve targeted photoactivity of Verteporfin in cancer cells.

Nanotechnology development provides new strategies to treat cancer by integration of different treatment modalities in a single multifunctional nanoparticle. In this scenario, we applied the multifunctional Pluronic P123/F127 mixed micelles for Verteporfin-mediated photodynamic therapy in PC3 and MCF-7 cancer cells. Micelles functionalization aimed the targeted delivery by the insertion of biotin moiety on micelle surface and fluorescence image-based through rhodamine-B dye conjugation in the polymer chains. Multifunctional Pluronics formed spherical nanoparticulated micelles that efficiently encapsulated the photosensitizer Verteporfin maintaining its favorable photophysical properties. Lyophilized formulations were stable at least for 6months and readily reconstituted in aqueous media. The multifunctional micelles were stable in protein-rich media due to the dual Pluronic mixed micelles characteristic: high drug loading capacity provided by its micellar core and high kinetic stability due its biocompatible shell. Biotin surface functionalized micelles showed higher internalization rates due biotin-mediated endocytosis, as demonstrated by competitive cellular uptake studies. Rhodamine B-tagged micelles allowed monitoring cellular uptake and intracellular distribution of the formulations. Confocal microscopy studies demonstrated a larger intracellular distribution of the formulation and photosensitizer, which could drive Verteporfin to act on multiple cell sites. Formulations were not toxic in the dark condition, but showed high Verteporfin-induced phototoxicity against both cancer cell lines at low drug and light doses. These results point Verteporfin-loaded multifunctional micelles as a promising tool to further developments in photodynamic therapy of cancer.

Preparation, properties and anticancer effects of mixed As4S4/ZnS nanoparticles capped by Poloxamer 407.

Arsenic sulfide compounds have a long history of application in a traditional medicine. In recent years, realgar has been studied as a promising drug in cancer treatment. In this study, the arsenic sulfide (As4S4) nanoparticles combined with zinc sulfide (ZnS) ones in different molar ratio have been prepared by a simple mechanochemical route in a planetary mill. The successful synthesis and structural properties were confirmed and followed via X-ray diffraction and high-resolution transmission electron microscopy measurements. The morphology of the particles was studied via scanning electron microscopy and transmission electron microscopy methods and the presence of nanocrystallites was verified. For biological tests, the prepared As4S4/ZnS nanoparticles were further milled in a circulation mill in a water solution of Poloxamer 407 (0.5wt%), in order to cover the particles with this biocompatible copolymer and to obtain stable nanosuspensions with unimodal distribution. The average size of the particles in the nanosuspensions (~120nm) was determined by photon cross-correlation spectroscopy method. Stability of the nanosuspensions was determined via particle size distribution and zeta potential measurements, confirming no physico-chemical changes for several months. Interestingly, with the increasing amount of ZnS in the sample, the stability was improved. The anti-cancer effects were tested on two melanoma cell lines, A375 and Bowes, with promising results, confirming increased efficiency of the samples containing both As4S4 and ZnS nanocrystals.

Poloxamer 407/188 binary thermosensitive hydrogels as delivery systems for infiltrative local anesthesia: Physico-chemical characterization and pharmacological evaluation.

In this study, we reported the development and the physico-chemical characterization of poloxamer 407 (PL407) and poloxamer 188 (PL188) binary systems as hydrogels for delivering ropivacaine (RVC), as drug model, and investigate their use in infiltrative local anesthesia for applications on the treatment of post-operative pain. We studied drug-micelle interaction and micellization process by light scattering and differential scanning calorimetry (DSC), the sol-gel transition and hydrogel supramolecular structure by small-angle-X-ray scattering (SAXS) and morphological evaluation by Scanning Electron Microscopy (SEM). In addition, we have presented the investigation of drug release mechanisms, in vitro/in vivo toxic and analgesic effects. Micellar dimensions evaluation showed the formation of PL407-PL188 mixed micelles and the drug incorporation, as well as the DSC studies showed increased enthalpy values for micelles formation after addition of PL 188 and RVC, indicating changes on self-assembly and the mixed micelles formation evoked by drug incorporation. SAXS studies revealed that the phase organization in hexagonal structure was not affected by RVC insertion into the hydrogels, maintaining their supramolecular structure. SEM analysis showed similar patterns after RVC addition. The RVC release followed the Higuchi model, modulated by the PL final concentration and the insertion of PL 188 into the system. Furthermore, the association PL407-PL188 induced lower in vitro cytotoxic effects, increased the duration of analgesia, in a single-dose model study, without evoking in vivo inflammation signs after local injection.

Preparation of Pluronic Grafted Dendritic alpha,epsilon-poly(L-lysine)s and Characterization as a Delivery Adjuvant of Antisense Oligonucleotide.

A series of pluronic grafted dendritic alpha,epsilon-poly(L-lysine)s (DPL-PF127) were synthesized by a conjugation reaction and evaluated the potential use of DPL-PF127 as a delivery agent of antisense oligonucleotide into A375 B3 cells. The structural features of the DPL-PF127 were identified by NMR and FT-IR. The number of pluronic F127 on DPL surface, determined by fluorescamine assay, increased proportionally to the mole ratio between DPL and activated PF127 in reaction. DPL- PF127 showed the physical properties of decrease in zetapotential and increase in size as the mole ratio of PF127 to DPL increased. The complex formation of DPL-PF127 with oligonucleotide was confirmed by running capillary zone electrophoresis (CZE) and agarose gel electrophoresis. DPL-PF127, prepared at the mole ratio of 1:10 in reaction, was the most suitable as a delivery adjuvant of oligonucleotide. In addition, DPL-PF127/oligonucleotide complexes were taken into A375B3 cell without cellular toxicity and delivered antisense oligonucleotide into cell.

Screening of Nanoemulsion Formulations and Identification of NB-201 as an Effective Topical Antimicrobial for Staphylococcus aureus in a Mouse Model of Infected Wounds.

Despite advances in antimicrobial therapies, wound infection remains a global public health concern. We aimed to formulate and assess various nanoemulsions (NEs) for potential effectiveness as stable antimicrobial agents suitable for topic application. A total of 106 NEs were developed that varied with respect to nonionic and cationic surfactants. Stability testing demonstrated that the NEs tested are broadly stable, with 97/106 formulations passing 2-week stability tests. Two NEs, NB-201 and NB-402, were selected to test antimicrobial activity in a wound model in mice. Skin abrasion wounds were infected with Staphylococcus aureus followed by NE treatment. Infected skin was then evaluated by measuring colony forming units. NB-201 reduced median bacterial counts by 4 to 5 log compared to animals treated with saline, whereas NB-402 reduced bacterial counts by 2 to 3 log. Additional stability tests on NB-201 demonstrated that NB-201 is stable in the presence of human serum, and is stable for at least 6 months at 5°C, 25°C, and 40°C. Finally, in in vitro studies, NB-201 was found to be effective against S. aureus at a higher dilution than the commercially available silver sulfadiazine. Altogether these results demonstrate that NB-201 is a stable and effective topical antimicrobial for the treatment of S. aureus.

A single CT-guided percutaneous intraosseous injection of thermosensitive simvastatin/poloxamer 407 hydrogel enhances vertebral bone formation in ovariectomized minipigs.

UNLABELLED: The ultimate goal of osteoporosis treatment is prevention of fragile fracture. Local treatment targeting specific bone may decrease the incidence of osteoporotic fractures. We developed an injectable, thermosensitive simvastatin/poloxamer 407 hydrogel; a single CT-guided percutaneous intraosseous injection augmented vertebrae in ovariectomized minipigs. INTRODUCTION: The greatest hazard associated with osteoporosis is local fragility fractures. An adjunct, local treatment might be helpful to decrease the incidence of osteoporotic fracture. Studies have found that simvastatin stimulates bone formation, but the skeletal bioavailability of orally administered is low. Directly delivering simvastatin to the specific bone that is prone to fractures may reinforce the target bone and reduce the incidence of fragility fractures. METHODS: We developed an injectable, thermosensitive simvastatin/poloxamer 407 hydrogel, conducted scanning electron microscopy, rheological, and drug release analyses to evaluate the delivery system; injected it into the lumbar vertebrae of ovariectomized minipigs via minimally invasive CT-guided percutaneous vertebral injection. Three months later, BMD, microstructures, mineral apposition rates, and strength were determined by DXA, micro-CT, histology, and biomechanical test; expression of VEGF, BMP2, and osteocalcin were analyzed by immunohistochemistry and Western blots. RESULTS: Poloxamer 407 is an effective controlled delivery system for intraosseous-injected simvastatin. A single injection of the simvastatin/poloxamer 407 hydrogel significantly increased BMD, bone microstructure, and strength; the bone volume fraction and trabecular thickness increased nearly 150 %, bone strength almost doubled compared with controls (all P < 0.01); and induced higher expression of VEGF, BMP2, and osteocalcin. CONCLUSIONS: CT-guided percutaneous vertebral injection of a single simvastatin/poloxamer 407 thermosensitive hydrogel promotes bone formation in ovariectomized minipigs. The underlying mechanism appears to involve the higher expression of VEGF and BMP-2.

Nanoemulsion Therapy for Burn Wounds Is Effective as a Topical Antimicrobial Against Gram-Negative and Gram-Positive Bacteria.

The aim of this study is to investigate the antimicrobial efficacy of two different nanoemulsion (NE) formulations against Gram-positive and Gram-negative bacteria in an in vivo rodent scald burn model. Male Sprague-Dawley rats were anesthetized and received a partial-thickness scald burn. Eight hours after burn injury, the wound was inoculated with 1 × 10(8) colony-forming units of Pseudomonas aeruginosa or Staphylococcus aureus. Treatment groups consisted of two different NE formulations (NB-201 and NB-402), NE vehicle, or saline. Topical application of the treatment was performed at 16 and 24 hours after burn injury. Animals were killed 32 hours after burn injury, and skin samples were obtained for quantitative wound culture and determination of dermal inflammation markers. In a separate set of experiments, burn wound progression was measured histologically after 72 hours of treatment. Both NE formulations (NB-201 and NB-402) significantly reduced burn wound infections with either P. aeruginosa or S. aureus and decreased median bacterial counts at least three logs when compared with animals with saline applications (p < .0001). NB-201 and NB-402 also decreased dermal neutrophil recruitment and sequestration into the wound as measured by myeloperoxidase (MPO) assay and histopathology (p < .05). In addition, there was a decrease in the proinflammatory dermal cytokines (interleukin 1-beta [IL-1ß], IL-6, and tumor necrosis factor alpha [TNF-α]) and the neutrophil chemoattractants CXCL1 and CXCL2. Using histologic examination, it was found that both NB-201 and NB-402 appeared to suppress burn wound progression 72 hours after injury. Topically applied NB-201 and NB-402 are effective in decreasing Gram-positive and Gram-negative bacteria growth in burn wounds, reducing inflammation, and abrogating burn wound progression.

Green synthesis of silver nanoparticles using cranberry powder aqueous extract: characterization and antimicrobial properties.

BACKGROUND: The growing threat of microbial resistance against traditional antibiotics has prompted the development of several antimicrobial nanoparticles (NPs), including silver NPs (AgNPs). In this article, a simple and eco-friendly method for the synthesis of AgNPs using the cranberry powder aqueous extract is reported. MATERIALS AND METHODS: Cranberry powder aqueous extracts (0.2%, 0.5%, and 0.8% w/v) were allowed to interact for 24 hours with a silver nitrate solution (10 mM) at 30°C at a ratio of 1:10. The formation of AgNPs was confirmed by ultraviolet-visible spectroscopy and their concentrations were determined using atomic absorption spectroscopy. The prepared NPs were evaluated by transmission electron microscopy, measurement of ζ-potential, and Fourier-transform infrared spectroscopy. The in vitro antimicrobial properties of AgNPs were then investigated against several microbial strains. Finally, in vivo appraisal of both wound-healing and antimicrobial properties of either plain AgNPs (prepared using 0.2% extract) or AgNP-Pluronic F-127 gel was conducted in a rat model after induction of a Staphylococcus aureus ATCC 6538P wound infection. RESULTS: The formation of AgNPs was confirmed by ultraviolet-visible spectroscopy, where a surface-plasmon resonance absorption peak was observed between 432 and 438 nm. Both size and concentration of the formed AgNPs increased with increasing concentration of the extracts. The developed NPs were stable, almost spherical, and polydisperse, with a size range of 1.4-8.6 nm. The negative ζ-potential values, as well as Fourier-transform infrared spectroscopy analysis, indicated the presence of a capping agent adsorbed onto the surface of the particles. In vitro antimicrobial evaluation revealed a size-dependent activity of the AgNPs against the tested organisms. Finally, AgNPs prepared using 0.2% extract exhibited a substantial in vivo healing potential for full-thickness excision wounds in rats. CONCLUSION: AgNPs were successfully synthesized from a silver nitrate solution through a simple green route, using cranberry powder aqueous extract as a reducing as well as capping agent.

Assessment of four experimental models of hyperlipidemia.

Various animal models of hyperlipidemia are used in research. Four rodent hyperlipidemia experimental models are examined in this study: three chronic hyperlipidemia models based on dietary supplementation with lipid or sucrose for 3 months and one acute hyperlipidemia model based on administration of the nonionic surfactant poloxamer. Neither lipid supplementation nor sucrose supplementation in Wistar rats was effective for establishing hyperlipidemia. Combining both lipid and sucrose supplementation in BALB/c mice induced hypercholesterolemia, as reflected in a considerable increase in blood cholesterol concentration, but did not produce an increase in blood triglyceride concentration. Poloxamer administration in C57BL/J6 mice produced increases in blood cholesterol and triglyceride concentrations. The authors conclude that supplementation of both lipid and sucrose in BALB/c mice was the most effective method for developing chronic hypercholesterolemia.

A high-throughput model of post-traumatic osteoarthritis using engineered cartilage tissue analogs.

OBJECTIVE: A number of in vitro models of post-traumatic osteoarthritis (PTOA) have been developed to study the effect of mechanical overload on the processes that regulate cartilage degeneration. While such frameworks are critical for the identification therapeutic targets, existing technologies are limited in their throughput capacity. Here, we validate a test platform for high-throughput mechanical injury incorporating engineered cartilage. METHOD: We utilized a high-throughput mechanical testing platform to apply injurious compression to engineered cartilage and determined their strain and strain rate dependent responses to injury. Next, we validated this response by applying the same injury conditions to cartilage explants. Finally, we conducted a pilot screen of putative PTOA therapeutic compounds. RESULTS: Engineered cartilage response to injury was strain dependent, with a 2-fold increase in glycosaminoglycan (GAG) loss at 75% compared to 50% strain. Extensive cell death was observed adjacent to fissures, with membrane rupture corroborated by marked increases in lactate dehydrogenase (LDH) release. Testing of established PTOA therapeutics showed that pan-caspase inhibitor [Z-VAD-FMK (ZVF)] was effective at reducing cell death, while the amphiphilic polymer [Poloxamer 188 (P188)] and the free-radical scavenger [N-Acetyl-L-cysteine (NAC)] reduced GAG loss as compared to injury alone. CONCLUSIONS: The injury response in this engineered cartilage model replicated key features of the response of cartilage explants, validating this system for application of physiologically relevant injurious compression. This study establishes a novel tool for the discovery of mechanisms governing cartilage injury, as well as a screening platform for the identification of new molecules for the treatment of PTOA.

Effectiveness of Artocarpus lakoocha extract, poloxamer 407, on Enterococcus faecalis in vitro.

AIM: The antiviral activities of Artocarpus lakoocha (A. lakoocha) extract have been reported in a number of studies; however, data regarding its antibacterial capability are limited. The aim of the present study was to examine the effectiveness of A. lakoocha extract, poloxamer 407, on Enterococcus faecalis (E. faecalis). METHODS: The effect of the antimicrobial activity of A. lakoocha extract and A. lakoocha extract, poloxamer 407, against E. faecalis was investigated. The antibacterial efficacy of A. lakoocha extract, poloxamer 407, against E. faecalis was compared to calcium hydroxide in a tooth model. RESULTS: The minimal inhibitory concentration and minimal bactericidal concentration (MBC) of A. lakoocha extract against E. faecalis were 0.39 ± 0 mg/mL and 3.12 ± 0 mg/mL, respectively; the MBC of calcium hydroxide against E. faecalis was 31.25 ± 0 mg/mL. In the tooth model, the E. faecalis count in all groups significantly decreased as the depth into the dentin increased compared to the control. There were no significant differences between 4% A. lakoocha extract poloxamer and UltraCal XS at any time period (P > 0.05) with one exception: at a depth of 0.6 mm on day 5, UltraCal XS had a significantly greater colonization than 4% A. lakoocha extract poloxamer. CONCLUSION: A. lakoocha extract, poloxamer 407, might be a useful alternative for antimicrobial medication in endodontic treatment. However, controlled clinical studies to evaluate its efficacy are needed.

Preparation and evaluation of folate-modified cationic pluronic micelles for poorly soluble anticancer drug.

The aim of this study was to construct novel targeting polymeric micelles. Folate-Poly (ethylenimine)-Pluronic copolymers were synthesized. A paclitaxel (PTX)-loaded mixed micelles consisting of Folate-Poly (ethylenimine)-Pluronic and Pluronic L121 copolymers have been developed. The mixed micelles showed nano-sized spherical morphology. The solubilization capacity of the mixed micelles was higher than Folate-Poly (ethylenimine)-Pluronic micelles because L121 has high solubilization capacity. MTT colorimetric test revealed that PTX in Folate-Poly (ethylenimine)-Pluronic micelles demonstrated the maximum anticancer activity. Pluronic-poly (ethylenimine) micelles and folate-modified Pluronic-poly(ethylenimine) micelles showed a marked increase of cellular accumulation compared with Pluronic P123 micelles. The biodistribution and retention of intravenously (i.v.) administered micelles to rats were determined. Folate-Poly (ethylenimine)-Pluronic micelles demonstrated enhanced pulmonary retention in rats after injection when compared to Pluronic P123 micelles.

Chylomicron formation and secretion is required for lipid-stimulated release of incretins GLP-1 and GIP.

Glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) are incretins produced in the intestine that play a central role in glucose metabolism and insulin secretion. Circulating concentrations of GLP-1 and GIP are low and can be difficult to assay in rodents. These studies utilized the novel intestinal lymph fistula model we have established to investigate the mechanism of lipid-stimulated incretin secretion. Peak concentrations of GLP-1 and GIP following an enteral lipid stimulus (Liposyn) were significantly higher in intestinal lymph than portal venous plasma. To determine whether lipid-stimulated incretin secretion was related to chylomicron formation Pluronic L-81 (L-81), a surfactant inhibiting chylomicron synthesis, was given concurrently with Liposyn. The presence of L-81 almost completely abolished the increase in lymph triglyceride seen with Liposyn alone (P < 0.001). Inhibition of chylomicron formation with L-81 reduced GLP-1 secretion into lymph compared to Liposyn stimulation alone (P = 0.034). The effect of L-81 relative to Liposyn alone had an even greater effect on GIP secretion, which was completely abolished (P = 0.004). These findings of a dramatic effect of L-81 on lymph levels of GLP-1 and GIP support a strong link between intestinal lipid absorption and incretin secretion. The relative difference in the effect of L-81 on the two incretins provides further support that nutrient-stimulation of GIP and GLP-1 is via distinct mechanisms.