The self-microemulsion formulation of potassium dehydroandrographolidi succinas (PDS) has been optimized and the performance in vitro has been evaluated preliminary. Kinds of prescription accessories were screened by solubility based on the emulsifying result and efficiency, particle size of emulsions. The optimal formulation composition and compatibility proportion were determined by orthogonal design and pseudo-ternary phase diagrams. The appearance, particle size, Zeta potential and stability of this formulation were also investigated. The optimized prescription of PDS was 10% MCT, 40% Tween-20 and 50% glycerol. It can spontaneously form a transparent pale blue opalescent emulsion with emulsification time 31.27 s, particle size 37.1 nm, Zata potential -17.4 mV and good stability.

Contaminations of SARS-CoV-2 have been found for many times in imported cold chain aquatic products and their packaging materials in China. The purpose of this paper is to analyze the contamination status, sources and transmission risks of SARS-CoV-2 in imported cold chain aquatic products, and try to put forward relevant suggestions and strategies in order to provide evidence for the prevention and control of SARS-CoV-2 infection.

To establish vascular endothelial growth factor (VEGF) and interleukin-8 (IL-8) as secretary biomarkers for cell growth on topographic substrates, we have evaluated the secretion and expression of these 2 factors by SH-SY5Y human neuroblastoma cells on poly-L-lactide (PLLA) micropillar arrayed topographic substrates. We fabricated topographic substrates with UV lithography, silicon etching and polydimethylsiloxane-based replica molding, and interfaced SH-SY5Y human neuroblastoma cells with both the topographic substrates and PLLA flat substrates. Cell morphology and spreading were examined with scanning electron microscopy. The secretion and mRNA expression of VEGF and IL-8 were evaluated with enzyme linked immunosorbent assay (ELISA) and real time qPCR, respectively, 24 hours after cell plating. We successfully achieved 4 topographic substrates with a nominal pillar diameter of 2 microm and 4 microm, and a nominal pillar spacing of 2 microm and 7 microm. We found that the secretion and mRNA expression of VEGF and/or IL-8 by SH-SY5Y cells on 2-2 microm (pillar diameter-spacing), 4-2 microm and 4-7 microm topographic substrates were upregulated in comparison to those by cells on PLLA flat substrate, 24 hours after cell plating. Furthermore, both cytokines were even more substantially upregulated on the 2-7 microm substrate than on the other 3 topographic substrates. Compared to those on PLLA flat substrate, cells on topographic substrates showed significant changes in morphology (spreading area, perimeter and roundness), and the increase in the secretion and mRNA expression of VEGF and IL-8 was accompanied with a decrease in cell spreading areas. These results provided evidence that pillar arrayed topography was an important microenvironmental factor in affecting VEGF and IL-8 expression or secretion, and VEGF and IL-8 might serve as important secretary biomarkers for growth on topographic substrates by SH-SY5Y cells.
Biomarkers ; Cell Line ; Cell Proliferation ; Cellular Microenvironment ; Humans ; Interleukin-8 ; genetics ; secretion ; Neuroblastoma ; secretion ; Polyesters ; chemistry ; RNA, Messenger ; genetics ; Vascular Endothelial Growth Factor A ; genetics ; secretion

Objective To explore self-emulsifying particle size characterization methods and compare the regularity of various methods. Methods By setting the clarity level of turbidity standard solution, with two less soluble drugs-diterpene lactone compounds Chuanhuning and dihydropyridine drug nifedipine as model drugs, 10-12 clarity level prescriptions were selected from six different ternary phase diagram. Laser particle size scanner was used to determine the particle size, and UV-visible spectrophotometry to determine its absorbance. Three methods of particle size characterization rules were compared by drawing charts. Results There was a positive correlationship among droplet particle size, absorbance and clarity grade of emulsion formed by prescription in the same phase diagram. But, there was no regularity among droplet particle size, absorbance and clarity grade of emulsion formed by prescription in different phase diagram. Conclusion The droplet particle size of emulsion formed by prescription containing the same drugs and excipients in different proportions can be compared by clarity with visual method or absorbance with UV-visible spectrophotometer.

This study was aimed to prepare solid dispersions of Acanthopanax leaves total flavonoids in order to im-prove its bioavailability. PEG4000, PEG6000, F68, PVPK30 were used as carrier materials in the preparation of four different types of solid dispersion to screen the best type of carrier material and evaluate the amount of carrier mate-rial and its influence on the drug dissolution. Rutin was used as reference substance. NaNO2-Al(NO3)3-NaOH was used as the color system, with a UV spectrophotometer measured absorbance at 500 nm. The dissolution characteris-tics of different proportions of solid dispersions were examined in vitro. The results showed that compared with raw material, the in vitro drug release rate with PVPK30 as carrier material in the obtained solid dispersion of the pro-portion of the raw material was significantly improved, and the cumulative release rate was also increased significant-ly. It was concluded that the solid dispersion prepared by solvent method significantly improved in vitro drug release in water.

BACKGROUND:Accumulative evidence supports that co-culture technology can be applied to construct the tissue-engineered cartilage with excellent biological characters. OBJECTIVE:To elaborate the co-culture concept and conclude and analyze seed cell sources, cel mixed ratio, spatial y-defined co-culture models and biomaterials in co-culture systems to conclude and analyze the biological characters of tissue-engineered cartilage, and to prospect progression of co-culture systems in cartilage tissue engineering. METHODS:The first author retrieved the databases of PubMed, Web of Science, and CNKI for relative papers published from January 1976 to May 2016 using the keywords ofco-culture, co-culture systems;articular cartilage, chondrocytes, mesenchymal stem cells;tissue engineering, articular cartilage tissue engineeringin English and Chinese, respectively. Finally 60 literatures were included in result analysis, including 1 Chinese and 59 English articles. RESULTS AND CONCLUSION:Co-culture technology emphasizes the role of microenvironment in terms of various physical, chemical and biological factors in the cell processing. In cartilage tissue engineering, co-culture systems contribute to maintain the viability and natural cell phenotype of chondrocytes and induce cartilage differentiation of mesenchymal stem cells. In addition, co-culture technology provides a novel way for cartilage tissue engineering to overcome the shortage of chondrocytes and repair injury to the cartilage-subchondral bone. However, the mechanisms of cell-cell interaction in co-culture systems still need to be explored in depth, so as to optimize the co-culturing conditions and construct perfect tissue-engineered cartilage.

BACKGROUND:Cartilage tissue engineering has been widely used to achieve cartilage regeneration in vitro and repair cartilage defects. Tissue-engineered cartilage mainly consists of chondrocytes, cartilage scaffold and in vitro environment. OBJECTIVE:To mimic the environment of articular cartilage development in vivo, in order to increase the bionic features of tissue-engineered cartilage scaffold and effectiveness of cartilage repair. METHODS: Knee joint chondrocytes were isolated from New Zealand white rabbits, 2 months old, and expanded in vitro. The chondrocytes at passage 2 were seeded onto a scaffold of articular cartilage extracelular matrix in the concentration of 1×106/L to prepare cel-scaffold composites. Cel-scaffold composites were cultivated in an Instron bioreactor with mechanical compression (1 Hz, 3 hours per day, 10% compression) as experimental group for 7, 14, 24, 28 days or cultured staticaly for 1 day as control group. RESULTS AND CONCLUSION:Morphological observations demonstrated that the thickness, elastic modulus and maximum load of the composite in the experimental group were significantly higher than those in the control group, which were positively related to time (P < 0.05). Histological staining showed the proliferation of chondrocytes, formation of cartilage lacuna and synthesis of proteoglycan in the experimental group through hematoxylin-eosin staining and safranin-O staining, which were increased gradualy with mechanical stimulation time. These results were consistent with the findings of proteoglycan kit. Real-time quantitative PCR revealed that mRNA expressions of colagen type I and colagen type II were significantly higher in the experimental group than the control group (P < 0.05). The experimental group showed the highest mRNA expression of colagen type I and colagen type II at 21 and 28 days of mechanical stimulation, respectively (P < 0.05). With the mechanical stimulation of bioreactor, the cel-scaffold composite can produce more extracelular matrix, such as colagen and proteoglycan, strengthen the mechanical properties to be more coincident with thein vivo environment of cartilage development, and increase the bionic features. With the progress of tissue engineering, the clinical bioregeneration of damaged cartilage wil be achieved.

OBJECTIVETo investigate the clinical and pathological features of progressive muscular dystrophy (PMD) in children and to provide help for the early and accurate diagnosis of PMD.

METHODSRetrospective analysis was performed on the clinical data of 99 hospitalized children with PMD, including clinical manifestations, age of onset, family history, creatase, electromyogram (EMG) and pathological changes of muscles.

RESULTSOf the 99 children with PMD, the age of onset was 0.5-14.5 (4.7 ± 3.1) years. Eleven cases (11%) had a family history of PMD. Twenty-six (26%) were misdiagnosed as other diseases. All patients presented with muscle weakness when seeing the doctor, and 66 (67%) of them had muscle atrophy and/or hypertrophy. All patients had elevated creatine kinase (CK) levels. The 2-7-year-old group (n=51) had a mean CK level of 9965 ± 8876 U/L, and the 7-15-year-old group (n=48) had a mean CK level of 5110 ± 4498 U/L, with a significant difference between the two groups (P<0.01). The EMG examination performed on 66 patients showed that 54 cases (82%) had myogenic damage and 10 cases (15%) had neurogenic damage. Light microscopy revealed coexistence of atrophy and hypertrophy of muscle fibers, hyaline degeneration and granular degeneration. Electron microscopy showed that muscle fibers were different in thickness, some atrophic or hypertrophic; muscle cell nuclei moved inwardly, myofilaments dissolved and disappeared mildly under the sarcolemma, there were scattered melting lesions within muscle fibers, the numbers of glycogen granules and mitochondria increased, mild hyperplasia and expansion of sarcoplasmic reticulum were seen, and a small number of muscle fibers had necrosis.

CONCLUSIONSWeakness of both lower extremities remains the main reason for PMD patients seeing the doctor. CK is the main laboratory indicator for diagnosis of PMD. PMD is mainly manifested as myogenic damage in the early stage and may be accompanied by neurogenic damage in the late stage, according to the EMG examination. With a high misdiagnosis rate, PMD may be misdiagnosed as many other diseases. Pathological examination under light microscope and electron microscope is the main means for confirming a PMD diagnosis.

Adolescent ; Child ; Child, Preschool ; Creatine Kinase ; blood ; Electromyography ; Female ; Humans ; Male ; Muscle, Skeletal ; pathology ; Muscular Dystrophies ; pathology ; physiopathology ; Retrospective Studies

Objective To investigate the effects of the novel scaffold on repairing large,high-loadbearing osteochondral defects of femoral head in a canine model.Methods The biphasic scaffolds were fabricated using cartilage extracellular matrix (ECM)-derived scaffold (cartilage layer) and acellular bone matrix (bone layer) by phase separation technique.Articular high-load-bearing osteochondral defects with a diameter of 11-mm and the depth of 10-mm were created in femoral heads.The defects were treated with constructs of a biphasic scaffold seeded with chondrogenically induced bone marrow-derived mesenehymal stem cells (BMSCs).The outcomes were evaluated for gross morphology,histological,biomechanical and micro-CT analysis at the third and sixth month after implantation.Results The gross and X-ray results showed femoral head slightly collapsed at the third month and severely collapse at the sixth month.Histological analysis showed cartilage defects were repaired with fibrous tissue or fibrocartilage with severe osteoarthritis and the varied degrees of the collapse of femoral heads were presented.Micro-CT showed that the values of bone volume fraction in defect area were always lower than those of the normal area in the femoral heads.Biomechanical analysis showed rigidity of the subchondral bone in defect area was significantly lower than that in normal area in the femoral heads at the sixth month.Conclusion The ECM-derived,integrated biphasic scaffold seeded with chondrogenically induced BMSCs could not successfully repair the large high-load-bearing osteochondral defects of the femoral head.

Contaminations of SARS-CoV-2 have been found for many times in imported cold chain aquatic products and their packaging materials in China. The purpose of this paper is to analyze the contamination status, sources and transmission risks of SARS-CoV-2 in imported cold chain aquatic products, and try to put forward relevant suggestions and strategies in order to provide evidence for the prevention and control of SARS-CoV-2 infection.