Dissolving-co-catalytic strategy for the preparation of flexible and wet-stable cellulose membrane towards biodegradable packaging.

In the realization of the goal of circular economy, cellulose as one of sustainable biomass resources, have attracted much attention because of their abundant sources, biodegradability and renewability. However, the mechanical and waterproof performance of cellulose-based materials are usually not satisfying, which limits their high-value utilization. In this study, cellulose membrane with high-performance from the aspects of mechanical properties, water-resistance ability, oxygen barrier capacity and biodegradability, was prepared from bleached hardwood pulp (HBKP) in a AlCl3/ZnCl2/H2O solution. The AlCl3/ZnCl2/H2O acted as both solvent and catalyst to dissolve cellulose and facilitate the chemical crosslinking of epichlorohydrin (EPI) with cellulose, thus improved the overall performance of the obtained cellulose membrane. The addition sequence, amount and crosslinking time of EPI during chemical crosslinking had important effects on the properties of the membranes. When 7 wt% EPI was crosslinked for 24 h, the tensile stress reached 133 MPa and the strain reached 17 %. Moreover, the membrane had excellent oxygen insulation down to (1.1 ± 0.31) × 10-4 cm3/m2·d·Pa, and good water-resistance ability, no obvious swelling behavior after 450 days of immersion in distilled water. Furthermore, the membrane could be degraded by microorganisms in about 20 days. This cellulose-based membrane offers a sustainable and biodegradable packaging material.

Anti-Melanoma Activity of Single Intratumoral Injection of ZnPc Micelles Mixed With in situ Gel in B16 Bearing Mouse.

Photodynamic therapy (PDT) is a potential treatment strategy for melanoma. As a second-generation photosensitizer, Zinc phthalocyanine (ZnPc) has many advantages for anti-tumor PDTs, such as strong absorption in the red and near infrared regions, high photo and chemical stability, etc. However, ZnPc has a poor water solubility and is apt to aggregate due to the π-π interaction between molecules, which limits its applications. In this study, various solvents and surfactants were screened for dissolving ZnPc and preparing ZnPc@SDC-TPGS micelle and thermosensitive in situ gel. After the cytotoxic effects of thermosensitive gels on PDT were tested, the antitumor effects on PDT of them in mice by intratumoral injection were evaluated, including body weight, and tumor weight, volume and morphology. The cell death pathway and the relationship of reactive oxygen species yield with apoptotic rate of tumor cells induced by ZnPc in situ gel were investigated. The results were that N-methyl-pyrrolidone (NMP) mixed with 2 % SDC and aqueous solution containing 2 % TPGS and 2 % SDC were used to synthesize ZnPc@SDC-TPGS micelle and the thermosensitive in situ gel. The cytotoxic effects of thermosensitive gels showed good tumor suppression of ZnPc@SDC-TPGS in situ gel and no toxicity of the blank gel. Intratumoral injection in situ gel containing 3 µg ZnPc under irradiation demonstrated good tumor inhibition in mice with melanoma. Apoptosis has been established as the primary pathway of cell death, and the production of reactive oxygen species (ROS) plays a crucial role in cellular apoptosis induced by ZnPc@SDC-TPGS in situ gel. In conclusion, the intratumoral injection of ZnPc@SDC-TPGS thermosensitive in situ gel provides a promising local treatment option for melanoma.

Efficient Delivery of Curcumin by Alginate Oligosaccharide Coated Aminated Mesoporous Silica Nanoparticles and In Vitro Anticancer Activity against Colon Cancer Cells.

We designed and synthesized aminated mesoporous silica (MSN-NH2), and functionally grafted alginate oligosaccharides (AOS) on its surface to get MSN-NH2-AOS nanoparticles as a delivery vehicle for the fat-soluble model drug curcumin (Cur). Dynamic light scattering, thermogravimetric analysis, and X-ray photoelectron spectroscopy were used to characterize the structure and performance of MSN-NH2-AOS. The nano-MSN-NH2-AOS preparation process was optimized, and the drug loading and encapsulation efficiencies of nano-MSN-NH2-AOS were investigated. The encapsulation efficiency of the MSN-NH2-Cur-AOS nanoparticles was up to 91.24 ± 1.23%. The pH-sensitive AOS coating made the total release rate of Cur only 28.9 ± 1.6% under neutral conditions and 67.5 ± 1% under acidic conditions. According to the results of in vitro anti-tumor studies conducted by MTT and cellular uptake assays, the MSN-NH2-Cur-AOS nanoparticles were more easily absorbed by colon cancer cells than free Cur, achieving a high tumor cell targeting efficiency. Moreover, when the concentration of Cur reached 50 µg/mL, MSN-NH2-Cur-AOS nanoparticles showed strong cytotoxicity against tumor cells, indicating that MSN-NH2-AOS might be a promising tool as a novel fat-soluble anticancer drug carrier.

Mg/Al-LDH as a nano-adjuvant for pertussis vaccine: a evaluation compared with aluminum hydroxide adjuvant.

Background. Layered double hydroxide (LDH) has been demonstrated as a highly efficient antigen platform to induce effective and durable immune response. However, whether LDH nanoparticles could act as an adjuvant for pertussis vaccines is still unknown. Here we evaluated the potential of Mg/Al-LDH as a nano-adjuvant to improve immune response against pertussis and compared it with commercial aluminum hydroxide (AH) adjuvant.Method. The Mg/Al-LDH nanoparticles were synthesized by a hydrothermal reaction. The morphology, structure and size of Mg/Al-LDH were characterized by transmission electron microscope, x-ray diffraction and MALVERN particle analysis. The ovalbumin and Pertussis toxin (PTd) was adsorbed to Mg/Al-LDH. The immune response of antigen-LDH complex was evaluated in mice, compared with commercial adjuvant alum. Hematoxylin-eosin staining was used to evaluate the inflammatory response at injection site.Results. The synthetic Mg/Al-LDH nanoparticles showed a typical hexagonal lamellar structure. The average size of synthetic nanoparticles was 102.9 nm with PDI of 0.13 and zeta potential was 44.4 mV. Mg/Al-LDH nanoparticles effectively adsorbed protein antigen and mediated antigen uptake by DC cells. Animal experiments showed that Mg/Al-LDH gave enhancement in anti-pertussis toxin (PTd) humoral immune response, which was considerable to commercial AH adjuvant. Finally, Mg/Al-LDH produced a slighter inflammatory response than AH at injection site and this injury was quickly recovered.Conclusion. Our study demonstrated the potential of Mg/Al-LDH as an effective adjuvant for pertussis vaccine, which induced comparable antibody response and had a better safety compared with commercial AH adjuvant.

Efficacy and safety of interferon α-2b spray for herpangina in children: A randomized, controlled trial.

OBJECTIVES: The treatment of acute herpangina is inconsistent. We aim to evaluate the effectiveness and safety of interferon α-2b spray versus Ribavirin for this disease. METHODS: A randomized, controlled trial was conducted in eight hospitals in China between 2016 and 2018. 668 patients (1-7 years old) were randomized into an experimental group (treated with Interferon α-2b spray) or control group (received Ribavirin Aerosol). Body temperature returning to normal within 72 h and remaining so for 24 h was the primary outcome; release of oral herpes and adverse events were the secondary outcomes. RESULTS: (1) The average age of onset was 2.5 years old. (2) After 72 h treatment, body temperature of 98.5% patients in experimental group and 94.3% in control group returned to normal and remained so for 24 h (P = 0.004). The differences were greater at 48 h treatment (95.2% vs. 85.9%, P < 0.001) and at 24 h (77.5% vs. 66.5%, P = 0.001). (3) The rate of improved oral herpes in the experimental group was higher than that in control group (46.7% vs.37.1%, P = 0.011). No adverse reaction occurred. CONCLUSIONS: Local application of recombinant interferon α-2b spray showed better efficacy for acute herpangina in children. It was safe for use.

EV71 vaccination impact on the incidence of encephalitis in patients with hand, foot and mouth disease.

In order to analyze the effect of EV71 vaccination on the incidence of encephalitis in patients with HFMD, 292 cases were vaccinated, and 2,486 cases were not vaccinated which were collected in 2018 and 2019. It shows that the incidence rate of encephalitis in vaccinated patients was significantly lower than that in non-vaccinated (P = .028), which suggests that EV71 vaccine has a protective effect on the occurrence of encephalitis. But some EV71 vaccinated patients still developed into encephalitis showed that they had not produced protection or protection was weak against EV71-related encephalitis; the reasons require further investigation.

Arsenic trioxide encapsulated liposomes prepared via copper acetate gradient loading method and its antitumor efficiency.

In this study, arsenic trioxide (ATO) was encapsulated in liposomes via copper acetate (Cu(OAc)2) gradients and high entrapment efficiency of over 80% was obtained. The average particle size and the zeta-potential of the liposomes were detected to be 115.1 ±â€¯29.1 nm and -21.97 ±â€¯0.6 mV, respectively. The TEM images showed rod-like precipitates in the inner aqueous phase, which was supposed be due to the formation of insoluble ATO-Cu complex. The in vitro drug release of ATO-Cu liposomes exhibited a sustained release over 72 h, and the release rates decreased with the increase of the pH of release media. Pharmacokinetic and tissue distribution studies of ATO liposomes showed significantly reduced plasma clearance rate, increased AUC0-12 h and T1/2, and improved tumor distribution of As compared to iv administration of ATO solution. The anti-tumor effect of ATO loaded liposomes to S180 tumor-bearing mice was significantly improved with a tumor inhibition rate of 61.2%, meanwhile the toxicity of encapsulated ATO was greatly decreased. In conclusion, ATO can be effectively encapsulated into liposomes by remote loading method via Cu(OAc)2 gradients; the co-administration of ATO and Cu(II) via liposomal formulation may find wide applications in the treatment of various tumors.

Enhanced Antitumor Efficacy of Curcumin-Loaded PLGA Nanoparticles Coated with Unique Fungal Hydrophobin.

Modifications to the surface chemistry, charge, and hydrophilicity/hydrophobicity of nanoparticles are applicable approaches to the alterations of the in vivo fate of intravenously administered nano-sized drug carriers. The objective of this study is to investigate the in vitro and in vivo antitumor efficacies of curcumin PLGA nanoparticles in relation to their surface structural modification via self-assembling coating with unique fungal hydrophobin. The hydophobin-coated curcumin PLGA nanoparticles (HPB PLGA NPs) were obtained by simply soaking curcumin-loaded PLGA nanoparticles (PLGA NPs) in aqueous fungal hydrophobin solution. The in vitro drug release behavior of the HPB PLGA NPS was also tested. The cytotoxicity and cellular uptake of these nanoparticles were determined in HepG2, A549, and Hela cell lines using MTT assay method and CLSM observation. The in vivo antitumor activity was evaluated in Hela tumor xenografted mice model. Compared with the PLGA NPs, the size and zeta potential of the nanoparticles were changed after hydrophobin coating, whereas similar in vitro release pattern was observed. The pharmacodynamics study showed prolonged blood retention of both nano-formulations than that of free curcumin, but no significant difference between the hydrophobin coated and uncoated nanoparticles. It was found that HPB PLGA NPs had increased cytotoxicities, higher cellular uptake, and improved antitumor efficacy. Surface modification of nanoparticles via self-assembling of hydrophobin is a convenient and promising method of changing particle surface physiochemical properties and antitumor performances. Further investigations, especially on tissue distribution, were needed to assess the potential application of the hydrophobin self-assembling coating in nano-drug delivery carriers.

Inhalable liposomal powder formulations for co-delivery of synergistic ciprofloxacin and colistin against multi-drug resistant gram-negative lung infections.

The aim of this study was to design and characterize dry powder inhaler formulations of ciprofloxacin and colistin co-loaded liposomes prepared by the ultrasonic spray-freeze-drying (USFD) technique. Liposomal formulations and powder production parameters were optimized to achieve optimal characteristics and in-vitro performance such as encapsulation efficiency (EE), particle size, particle distribution index (PDI), fine particle fraction (FPF), emitted dose (ED) and in vitro antibacterial activity. The formulation (F6) with the mannitol (5% w/v) as the internal lyoprotectant and sucrose (5%, w/v), mannitol (10%, w/v) and leucine (5%, w/w) as the external lyoprotectants/aerosolization enhancers showed an optimal rehydrated EE values of ciprofloxacin and colistin (44.9 ± 0.9% and 47.0 ± 0.6%, respectively) as well as satisfactory aerosol performance (FPF: 45.8 ± 2.2% and 43.6 ± 1.6%, respectively; ED: 97.0 ± 0.5% and 95.0 ± 0.6%, respectively). For the blank liposomes, there was almost no inhibitory effect on the cell proliferation in human lung epithelial A549 cells, showing that the lipid materials used in the liposome formulation is safe for use in pulmonary drug delivery. The cytotoxicity study demonstrated that the optimized liposomal formulation (F6) was not cytotoxic at least at the drug concentrations of colistin 5 µg/mL and ciprofloxacin 20 µg/mL. Colistin (2 mg/L) monotherapy showed no antibacterial effect against P. aeruginosa H131300444 and H133880624. Ciprofloxacin (8 mg/L) monotherapy showed moderate bacterial killing for both clinical isolates; however, regrowth was observed in 6 h for P. aeruginosa H133880624. The liposomal formulation displayed superior antibacterial activity against clinical isolates of Pseudomonas aeruginosa H131300444 and P. aeruginosa H133880624 compared to each antibiotic per se. These results demonstrate that the liposomal powder formulation prepared by USFD could potentially be a pulmonary delivery system for antibiotic combination to treat multi-drug resistant Gram-negative lung infections.

Simultaneous Particle Size Reduction and Homogeneous Mixing to Produce Combinational Powder Formulations for Inhalation by the Single-Step Co-Jet Milling.

Homogeneous mixing of 2 cohesive jet-milled drug powders is a challenge for pharmaceutical manufacturing on account of their cohesive nature resulting in the formation of strong and random agglomerates. In this study, colistin and ciprofloxacin were co-jet milled to develop combinational antibiotic dry powder formulations for inhalation. The properties of particle size, morphology, content uniformity, and in vitro aerosolization were evaluated. The distribution of 2 drugs in the co-jet milled powders was assessed using time-of-flight-secondary ion mass spectrometry. The co-jet milled powders demonstrated an acceptable content uniformity indicating homogeneity. In general, time-of-flight-secondary ion mass spectrometry images showed relatively homogeneous distributions of ciprofloxacin and colistin in the co-milled formulations. Importantly, the 2 drugs generally had the similar fine particle fraction and deposition behavior in each combinational formulation supporting that the particle mixtures were relatively homogenous and could maximize the antimicrobial synergy. In conclusion, co-jet milling could be a viable technique to produce the combination powders for inhalation.

Extended tacrolimus release via the combination of lipid-based solid dispersion and HPMC hydrogel matrix tablets.

The objective of this study is to evaluate the feasibility of obtaining extended release of tacrolimus by a novel combination of lipid-based solid dispersion and matrix-type extended release tablet techniques. Tacrolimus solid dispersion was prepared using glycerylbehenate (Compritol® ATO888) and Pluronic F127 as the carrier materials with hot-melt method, which was then blended with hydrogel matrix materials, such as HPMC and lactose, the powders were directly compressed into tablets. In vitro drug release tests were carried out to evaluate the performance of the solid dispersions and the tablets. The dissolution rate of tacrolimus was significantly improved by the lipid-based solid dispersion, and the incorporation of HPC into the solid dispersion obviously improved its stability after storage. Extended release tablets loaded with tacrolimus solid dispersion showed prolonged drug release patterns over 24 h, the release patterns of the tablets can be tailored by the compositions of the matrix materials, including the types and content of HPMCs. A modified processing method that directly mixed the melted solid dispersion with HPMC powders improved the uniformity of the solid dispersion inside the tablet matrix and release profile. The release data of the extended release tablet fitted well to the Korsmeyer-Peppas model with n value of 0.85, which suggested diffusion- and erosion-controlled release mechanism. The combination of lipid-based solid dispersion and HPMC hydrogel matrix may find wide applications in the extended release dosage forms of high potent, water-insoluble drugs.

Improved dissolution and oral absorption by co-grinding active drug probucol and ternary stabilizers mixtures with planetary beads-milling method.

The objective of this work is to construct a nanosuspension drug delivery system of probucol, a BCS II drug, in order to improve its dissolution and oral bioavailability. The wet milling procedure using planetary beads-milling equipment was utilized to grind the raw probucol to ultrafine nanoparticle/nanocrystal aqueous suspension that was further solidified by freeze-drying process. Cellulose derivatives of different substitution groups and molecular weights, including HPMC, HPC, and MC, were evaluated as the primary stabilizer of probucol nanosuspension. Ternary stabilizers system composed of a primary stabilizer (cellulose derivative, i.e. HPC), a nonionic surfactant (Pluronic® F68), and an anionic surfactant (SDS) was employed to obtain probucol nanosuspension of finer particle size and enhanced dissolution in aqueous media. The probucol nanosuspension with good physical stability showed no obvious change of particle size even after storing over 7 d at 4 °C or 25 °C. The solidified probucol nanosuspension with trehalose as the cryoprotectant showed the highest dissolution rate (> 60% at 2 h) compared to other cryoprotectant. The in vivo pharmacokinetic evaluation indicated about 15-folds higher AUC value of the probucol nanosuspension compared to that of coarse probucol suspension after oral administration to rats. The probucol nanosuspension prepared by wet-milling and ternary stabilizers system may find wide applications for improving the dissolution and oral absorption of water-insoluble drugs.

Co-Delivery of Ciprofloxacin and Colistin in Liposomal Formulations with Enhanced In Vitro Antimicrobial Activities against Multidrug Resistant Pseudomonas aeruginosa.

PURPOSE: This study aims to develop liposomal formulations containing synergistic antibiotics of colistin and ciprofloxacin for the treatment of infections caused by multidrug-resistant Pseudomonas aeruginosa. METHODS: Colistin (Col) and ciprofloxacin (Cip) were co-encapsulated in anionic liposomes by ammonium sulfate gradient. Particle size, encapsulation efficiency, in vitro drug release and in vitro antibiotic activities were evaluated. RESULTS: The optimized liposomal formulation has uniform sizes of approximately 100 nm, with encapsulation efficiency of 67.0% (for colistin) and 85.2% (for ciprofloxacin). Incorporation of anionic lipid (DMPG) markedly increased encapsulation efficiency of colistin (from 5.4 to 67.0%); however, the encapsulation efficiency of ciprofloxacin was independent of DMPG ratio. Incorporation of colistin significantly accelerated the release of ciprofloxacin from the DMPG anionic liposomes. In vitro release of ciprofloxacin and colistin in the bovine serum for 2 h were above 70 and 50%. The cytotoxicity study using A549 cells showed the liposomal formulation is as non-toxic as the drug solutions. Liposomal formulations of combinations had enhanced in vitro antimicrobial activities against multidrug resistant P. aeruginosa than the monotherapies. CONCLUSIONS: Liposomal formulations of two synergistic antibiotics was promising against multidrug resistant P. aeruginosa infections.

Determination and Pharmacokinetics of WGA in Rat Plasma by LC-MS After Oral Administration of Xanthoceras sorbifolia Bunge Extract.

3-O-(3-O-angeloyl-6-O-ß-D-glucopyranosyl)-ß-D-glucopyranosyl-28-O-(2-α-L-rhamnopyranosyl-6-O-ß-D-glucopyranosyl)-ß-D-glucopyranosyl-16-deoxybarringtogenol A (WGA) is a potential anti-AD (Alzheimer's disease) active compound isolated from the husks of Xanthoceras sorbifolia Bunge. A rapid and accurate high-performance liquid chromatography-mass spectrometry (LC-MS) method was developed and validated for the quantification of WGA in rat plasma. Digoxin was used as internal standard (IS). Sample preparation was performed by liquid-liquid extraction using ethyl acetate-isopropanol (1:1, v/v). HPLC separation was carried out using a Venusil MP C18 column (150 mm × 4.6 mm, 5 µm). Isocratic elution was performed using methanol: water (70:30, v/v) as the mobile phase, at a flow rate of 0.8 mL/min. Analysis was performed in selected ion monitoring mode with a positive electrospray ionization interface. No endogenous interference was observed at the retention time of the analyte because of the high specificity of selected ion monitoring mode. The assay was validated to demonstrate the selectivity, linearity, recovery, accuracy, precision and stability. The lower limit of quantification (LLOQ) was 10.0 ng/mL. The developed and validated method has been successfully applied to the quantification and pharmacokinetic study of WGA in rats after oral administration of X. sorbifolia Bunge extract.

Improved oral bioavailability of probucol by dry media-milling.

The polymer/probucol co-milled mixtures were prepared to improve drug dissolution rate and oral bioavailability. Probucol, a BCS II drug, was co-milled together with Copovidone (Kollidon VA64, VA64), Soluplus, or MCC using the dry media-milling process with planetary ball-milling equipment. The properties of the milled mixtures including morphology, crystal form, vitro drug dissolution and in vivo oral bioavailability in rats were evaluated. Probucol existed as an amorphous in the matrix of the co-milled mixtures containing VA64, which helped to enhance drug dissolution. The ternary mixture composed of VA64, RH40, and probucol showed increased dissolution rates in both sink and non-sink conditions. It also had a higher oral bioavailability compared to the reference formulation. Dry-media milling of binary or ternary mixtures composed of drug, polymer and surfactant possibly have wide applications to improve dissolution rate and oral bioavailability of water-insoluble drugs.

Mixed PEGylated surfactant modifying system decrease the accelerated blood clearance phenomenon of nanoemulsions in rats.

The accelerated blood clearance (ABC) phenomenon which is induced by repeated injection of poly (ethylene glycol) (PEG)-coated colloidal carriers gives clinical challenge to the promising drug delivery system. It is necessary to decrease this unexpected immunological response. A novel 4-arm poly (ethylene glycol-5000)4-cholesteryl methyl amide (4-arm PEG5000-CHMA) has been synthesized. The structure of 4-arm PEG5000-CHMA was confirmed by IR and 1H-NMR spectrum. The pharmacokinetics of the tocopheryl nicotinate (TN)-loaded nanoemulsions modified with 4-arm PEG5000-CHMA or/and 1, 2-distearoyl-Sn-glycero-3-phosphoethanolamine-n-[methoxy(poly-ethyleneglycol)-2000] (mPEG2000-DSPE) have been studied. Furthermore, the ABC phenomenon has been detailed investigated in rats by TN-loaded nanoemulsions modified with 4-arm PEG5000-CHMA and mPEG2000-DSPE (CPNE). The plasma levels of TN and anti-PEG IgM antibody were determined by HPLC and ELISA, respectively. The circulation time of the CPNEs were comparable to the mPEG2000-DSPE coated nanoemulsions. Moreover, the ABC phenomenon can be decreased by CPNEs. This study designs a method to decrease the ABC phenomenon and develops a clinical promising nanoemulsion for therapeutic or imaging purpose.

Developmental Changes in Pain and Spinal Immune Gene Expression after Radicular Trauma in the Rat.

Neuropathic pain is chronic pain that develops after nerve injury and is less frequent in infants and children than in adults. Likewise, in animal models of neuropathic pain, allodynia and hyperalgesia are non-existent or attenuated in the infant, with a "switch" during development by which acute nerve injury transitions to chronic pain. Concomitant with the delay in neuropathic pain, there is a parallel delay in the ability of nerve injury to activate the immune system. Models of neuropathic pain in the infant have used various ligation methods and find that neuropathic pain does not occur under after postnatal days 21-28 (PN21-PN28), linked to activation of immune processes and developmental regulation of anti-inflammatory cytokines. We applied a model of neuropathic pain in the adult using a transient compression of the cervical nerve or nerve root in infant rats (injured at 10, 14, 21, or 28 days of age) to define transition periods during which injury results in no change in thermal and mechanical pain sensitivity or in short-term changes in pain. There was little to no hyperalgesia when the injury was imposed at PN10, but significant thermal hyperalgesia and mechanical allodynia 1 day after compression injury when performed at PN14, 21, or 28. Thermal withdrawal latencies returned to near baseline by 7 days postsurgery when the injuries were at PN14, and lasted up to 14 days when the injury was imposed at PN28. There was mechanical allodynia following injury at 1 day postinjury and at 14 days after injury at PN14. Measurements of mRNA from spinal cord at 1, 7, and 14 days postinjury at PN14, 21, and 28 showed that both the magnitude and duration of elevated immune markers and chemokines/cytokines were greater in the older animals, corresponding to the development of hyperalgesia. Thus, we confirm the late onset of neuropathic pain but found no evidence of emergent hyperalgesia if the injury was before PN21. This may be due to the use of a transient, and not sustained, compression ligation model.

Association of Enterovirus 71 encephalitis with the interleukin-8 gene region in Chinese children.

The study was performed in 36 Chinese patients with Enterovirus 71 (EV71) encephalitis and 141 patients with EV71-related hand, foot and mouth disease (HFMD) without encephalitis. Genotyping was determined by polymerase chain reaction- restriction fragment length polymorphism. Patients with EV71 encephalitis had a significantly higher frequency of interleukin-8 (IL-8)-251TT genotype than patients with EV71-related HFMD without encephalitis (55.6% vs 31.2%, p = 0.023). The frequency of IL-8-251T alleles was significantly higher among patients with EV71 encephalitis than in patients with EV71-related HFMD without encephalitis (72.2% vs 58.9%, odds ratio 1.8, 95% confidence interval 1.0-3.2, p = 0.038). There were significant differences in gender, age, fever days, white blood cell count, C-reactive protein and blood glucose concentration and IL-8 levels among genotypes of IL-8-251A/T in EV71-infected patients, but no significant differences in alanine or aspartate aminotransferase, creatine kinase-myocardial isozyme and cerebrospinal fluid in patients with EV71 encephalitis. These findings suggest that the IL-8-251T allele is associated with susceptibility to EV71 encephalitis in Chinese patients.

A novel method to load topotecan into liposomes driven by a transmembrane NH4EDTA gradient.

Antitumor drugs not only cause cytocidal effect on cancer cells, but also damage on normal healthy tissues, resulting in side effects. Liposome encapsulation can result in reduced systematic distribution due to the enhanced permeability and retention (EPR) effect, accompanied by drug accumulation in liver, spleen, and other immune organs, which can cause damage to those organs. It has been demonstrated that EDTA, frequently used as a chelator, possesses a synergistic antitumor effect. Indeed, our previous study showed that EDTA could reduce the toxicity of anthracyclines to the heart and immune organs. In this study, we intended to encapsulate topotecan within liposome adopting transmembrane NH(4)EDTA gradient in order to increase the antitumor activity and decrease the toxicity against normal immune organs. Regarding the encapsulation efficiency of topotecan liposomes, both the pH value of the buffer and the cholesterol content showed significant effects on encapsulation and drug retention. Liposome encapsulation dramatically increased the antitumor activity of topotecan compared to free drug (p<0.05), while similar efficacy was obtained from liposomes prepared by a NH(4)EDTA gradient or a (NH(4))(2)SO(4) gradient (tumor inhibition ratios were 85.6% and 84.1%, respectively). However, a significant decrease in toxicity against the immune organs was found in liposomes prepared by a NH(4)EDTA gradient compared to those prepared by a (NH(4))(2)SO(4) gradient. These results suggest the superiority of the proposed gradient for topotecan encapsulation in decreasing its toxicity on immune systems.

Sustained liver targeting and improved antiproliferative effect of doxorubicin liposomes modified with galactosylated lipid and PEG-lipid.

In this study, a cleavable PEG-lipid (methoxypolyethyleneglycol 2000-cholesteryl hemisuccinate, PEG(2000)-CHEMS) linked via ester bond and galactosylated lipid ((5-cholesten-3beta-yl) 4-oxo-4-[2-(lactobionyl amido) ethylamido] butanoate, CHS-ED-LA) were used to modify doxorubicin (DOX) liposome. DOX was encapsulated into conventional liposomes (CL), galactosylated liposomes (modified with CHS-ED-LA, GalL), pegylated liposomes (modified with PEG(2000)-CHEMS, PEG-CL), and pegylated galactosylated liposomes (modified with CHS-ED-LA and PEG(2000)-CHEMS, PEG-GalL) using an ammonium sulfate gradient loading method and then intravenously injected to normal mice. Both PEG-GalL DOX and GalL DOX gave relatively high overall drug targeting efficiencies to liver ((T(e))(liver)) and were mainly taken up by hepatocyte. However, PEG-GalL DOX showed unique "sustained targeting" characterized by slowed transfer of DOX to liver and reduced peak concentrations in the liver. The biodistribution and antitumor efficacy of various DOX preparations were studied in hepatocarcinoma 22 (H22) tumor-bearing mice. The inhibitory rate of PEG-GalL DOX to H22 tumors was up to 94%, significantly higher than that of PEG-CL DOX, GalL DOX, CL DOX, and free DOX, although the tumor distribution of DOX revealed no difference between PEG-GalL DOX and PEG-CL DOX. Meanwhile, the gradual increase in the liver DOX concentration due to the sustained uptake of PEG-GalL DOX formulations resulted in lower damage to liver. In conclusion, the present investigation indicated that double modification of liposomes with PEG(2000)-CHEMS, and CHS-ED-LA represents a potentially advantageous strategy in the therapy of liver cancers or other liver diseases.