107 research outputs found
Sustained release of VEGF from PLGA nanoparticles embedded thermo-sensitive hydrogel in full-thickness porcine bladder acellular matrix
We fabricated a novel vascular endothelial growth factor (VEGF)-loaded poly(lactic-co-glycolic acid) (PLGA)-nanoparticles (NPs)-embedded thermo-sensitive hydrogel in porcine bladder acellular matrix allograft (BAMA) system, which is designed for achieving a sustained release of VEGF protein, and embedding the protein carrier into the BAMA. We identified and optimized various formulations and process parameters to get the preferred particle size, entrapment, and polydispersibility of the VEGF-NPs, and incorporated the VEGF-NPs into the (poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) (Pluronic®) F127 to achieve the preferred VEGF-NPs thermo-sensitive gel system. Then the thermal behavior of the system was proven by in vitro and in vivo study, and the kinetic-sustained release profile of the system embedded in porcine bladder acellular matrix was investigated. Results indicated that the bioactivity of the encapsulated VEGF released from the NPs was reserved, and the VEGF-NPs thermo-sensitive gel system can achieve sol-gel transmission successfully at appropriate temperature. Furthermore, the system can create a satisfactory tissue-compatible environment and an effective VEGF-sustained release approach. In conclusion, a novel VEGF-loaded PLGA NPs-embedded thermo-sensitive hydrogel in porcine BAMA system is successfully prepared, to provide a promising way for deficient bladder reconstruction therapy
Partial direct contact transmission in ferrets of a mallard H7N3 influenza virus with typical avian-like receptor specificity
<p>Abstract</p> <p>Background</p> <p>Avian influenza viruses of the H7 subtype have caused multiple outbreaks in domestic poultry and represent a significant threat to public health due to their propensity to occasionally transmit directly from birds to humans. In order to better understand the cross species transmission potential of H7 viruses in nature, we performed biological and molecular characterizations of an H7N3 virus isolated from mallards in Canada in 2001.</p> <p>Results</p> <p>Sequence analysis that the HA gene of the mallard H7N3 virus shares 97% identity with the highly pathogenic avian influenza (HPAI) H7N3 virus isolated from a human case in British Columbia, Canada in 2004. The mallard H7N3 virus was able to replicate in quail and chickens, and transmitted efficiently in quail but not in chickens. Interestingly, although this virus showed preferential binding to analogs of avian-like receptors with sialic acid (SA) linked to galactose in an α2–3 linkage (SAα2–3Gal), it replicated to high titers in cultures of primary human airway epithelial (HAE) cells, comparable to an avian H9N2 influenza virus with human-like α2–6 linkage receptors (SAα2–6Gal). In addition, the virus replicated in mice and ferrets without prior adaptation and was able to transmit partially among ferrets.</p> <p>Conclusion</p> <p>Our findings highlight the importance and need for systematic <it>in vitro </it>and <it>in vivo </it>analysis of avian influenza viruses isolated from the natural reservoir in order to define their zoonotic potential.</p
Development of Polysorbate 80/Phospholipid mixed micellar formation for docetaxel and assessment of its in vivo distribution in animal models
Docetaxel (DTX) is a very important member of taxoid family. Despite several alternative delivery systems reported recently, DTX formulated by Polysorbate 80 and alcohol (Taxotere®) is still the most frequent administration in clinical practice. In this study, we incorporated DTX into Polysorbate 80/Phospholipid mixed micelles and compared its structural characteristics, pharmacokinetics, biodistribution, and blood compatibility with its conventional counterparts. Results showed that the mixed micelles loaded DTX possessed a mean size of approximately 13 nm with narrow size distribution and a rod-like micelle shape. In the pharmacokinetics assessment, there was no significant difference between the two preparations (P > 0.05), which demonstrated that the DTX in the two preparations may share a similar pharmacokinetic process. However, the Polysorbate 80/Phospholipid mixed micelles can increase the drug residence amount of DTX in kidney, spleen, ovary and uterus, heart, and liver. The blood compatibility assessment study revealed that the mixed micelles were safe for intravenous injection. In conclusion, Polysorbate 80/Phospholipid mixed micelle is safe, can improve the tumor therapeutic effects of DTX in the chosen organs, and may be a potential alternative dosage form for clinical intravenous administration of DTX
Novel Reassortant Highly Pathogenic Avian Influenza (H5N5) Viruses in Domestic Ducks, China
In China, domestic ducks and wild birds often share the same water, in which influenza viruses replicate preferentially. Isolation of 2 novel reassortant highly pathogenic avian influenza (H5N5) viruses from apparently healthy domestic ducks highlights the role of these ducks as reassortment vessels. Such new subtypes of influenza viruses may pose a pandemic threat
Effect of a Traditional Chinese Medicine combined therapy on adolescent idiopathic scoliosis: a randomized controlled trial
AbstractObjectiveTo evaluate the effectiveness of a combined Traditional Chinese Medicine (TCM) therapy versus conventional treatment on adolescent idiopathic scoliosis.MethodsOne hundred twenty outpatients with mild and moderate adolescent idiopathic scoliosis were randomly divided into a TCM group (TCMG) and a brace group (CG). TCMG patients underwent Daoyin, Tuina, and acupotomology therapies. CG patients were treated with a Milwaukee brace. Each patient's Cobb angle was measured after 12 and 24 months of treatment, and pulmonary function was determined after 12 months of treatment. Average electromyogram (AEMG) ratio of the surface electromyogram was measured after 6 and 12 months of treatment and followed-up after 18 and 24 months.ResultsThe Cobb angle significantly decreased in both groups after 12 months of treatment compared with before treatment (P < 0.05). The percentages of original Cobb angle in TCMG and CG were 51.4% and 47.8% (P > 0.05) after 12 months and 62.5% and 34.7% (P < 0.05) after 24 months, respectively. Pulmonary function significantly improved after 12 months in TCMG (P < 0.05) but significantly decreased in CG (P < 0.05). The AEMG ratio was significantly lower (P < 0.01) and tended to remain at 1 after stopping treatment in TCMG, but increased in CG (P < 0.05).ConclusionTCM combined therapy can prevent the progression of scoliosis. The AEMG ratio is a promising index that could replace radiography in the evaluation of treatment effect and progression in scoliosis
A Wireless Electronic Nose System Using a Fe2O3 Gas Sensing Array and Least Squares Support Vector Regression
This paper describes the design and implementation of a wireless electronic nose (WEN) system which can online detect the combustible gases methane and hydrogen (CH4/H2) and estimate their concentrations, either singly or in mixtures. The system is composed of two wireless sensor nodes—a slave node and a master node. The former comprises a Fe2O3 gas sensing array for the combustible gas detection, a digital signal processor (DSP) system for real-time sampling and processing the sensor array data and a wireless transceiver unit (WTU) by which the detection results can be transmitted to the master node connected with a computer. A type of Fe2O3 gas sensor insensitive to humidity is developed for resistance to environmental influences. A threshold-based least square support vector regression (LS-SVR)estimator is implemented on a DSP for classification and concentration measurements. Experimental results confirm that LS-SVR produces higher accuracy compared with artificial neural networks (ANNs) and a faster convergence rate than the standard support vector regression (SVR). The designed WEN system effectively achieves gas mixture analysis in a real-time process
Replication and Transmission of H9N2 Influenza Viruses in Ferrets: Evaluation of Pandemic Potential
H9N2 avian influenza A viruses are endemic in poultry of many Eurasian countries and have caused repeated human infections in Asia since 1998. To evaluate the potential threat of H9N2 viruses to humans, we investigated the replication and transmission efficiency of H9N2 viruses in the ferret model. Five wild-type (WT) H9N2 viruses, isolated from different avian species from 1988 through 2003, were tested in vivo and found to replicate in ferrets. However these viruses achieved mild peak viral titers in nasal washes when compared to those observed with a human H3N2 virus. Two of these H9N2 viruses transmitted to direct contact ferrets, however no aerosol transmission was detected in the virus displaying the most efficient direct contact transmission. A leucine (Leu) residue at amino acid position 226 in the hemagglutinin (HA) receptor-binding site (RBS), responsible for human virus-like receptor specificity, was found to be important for the transmission of the H9N2 viruses in ferrets. In addition, an H9N2 avian-human reassortant virus, which contains the surface glycoprotein genes from an H9N2 virus and the six internal genes of a human H3N2 virus, showed enhanced replication and efficient transmission to direct contacts. Although no aerosol transmission was observed, the virus replicated in multiple respiratory tissues and induced clinical signs similar to those observed with the parental human H3N2 virus. Our results suggest that the establishment and prevalence of H9N2 viruses in poultry pose a significant threat for humans
Multivalent HA DNA Vaccination Protects against Highly Pathogenic H5N1 Avian Influenza Infection in Chickens and Mice
Sustained outbreaks of highly pathogenic avian influenza (HPAI) H5N1 in avian species increase the risk of reassortment and adaptation to humans. The ability to contain its spread in chickens would reduce this threat and help maintain the capacity for egg-based vaccine production. While vaccines offer the potential to control avian disease, a major concern of current vaccines is their potency and inability to protect against evolving avian influenza viruses.The ability of DNA vaccines encoding hemagglutinin (HA) proteins from different HPAI H5N1 serotypes was evaluated for its ability to elicit neutralizing antibodies and to protect against homologous and heterologous HPAI H5N1 strain challenge in mice and chickens after DNA immunization by needle and syringe or with a pressure injection device. These vaccines elicited antibodies that neutralized multiple strains of HPAI H5N1 when given in combinations containing up to 10 HAs. The response was dose-dependent, and breadth was determined by the choice of the influenza virus HA in the vaccine. Monovalent and trivalent HA vaccines were tested first in mice and conferred protection against lethal H5N1 A/Vietnam/1203/2004 challenge 68 weeks after vaccination. In chickens, protection was observed against heterologous strains of HPAI H5N1 after vaccination with a trivalent H5 serotype DNA vaccine with doses as low as 5 microg DNA given twice either by intramuscular needle injection or with a needle-free device.DNA vaccines offer a generic approach to influenza virus immunization applicable to multiple animal species. In addition, the ability to substitute plasmids encoding different strains enables rapid adaptation of the vaccine to newly evolving field isolates
STA-LUC scenario.zip
Supplementary Data for 'Effects of dust aerosols induced by land use and land cover change on direct radiative forcing in northern China from 2000 to 2020'.</p
DYN-LUC_scenario.zip
Supplementary Data for 'Effects of dust aerosols induced by land use and land cover change on direct radiative forcing in northern China from 2000 to 2020'.</p
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