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To assess the hepatoprotective activity of Glutathione S-transferase(GSTsw), extracted and purified from silkworm, in experimental acute mice liver injury and explore mechanisms. Mice were divided into five groups: control group, carbon tetrachloride (CCl4) group, and three treatment groups that received CCl4 and GSTsw at doses of 0.083 mg•g(-1), 0.0415 mg•g(-1) and 0.0207 mg•g(-1) for 3 days. ALT in serum, GST, SOD and T-AOC in liver tissue homogenate, and changes in liver pathology in the five groups were studied. CCl4 administration led to pathological and biochemical evidence of liver injury as compared to untreated controls. GSTsw administration led to significant protection against CCl4-induced changes in liver pathology. It was also associatedwith significantly lower serum ALT levels, higher GST-SOD and T-AOC level in live tissue homogenate. Thus, GSTsw showed protective activity against CCl4-induced hepatotoxicity in mice.

The DNA binding and cleavage properties of quercetin nickel (II) complex have been studied, but little attention has been devoted to the relationship between antitumor activity of this complex and DNA-binding properties. In the present study, we report that quercetin nickel (II) complex showed significant cytotoxicity against three tumor cell lines (HepG2, SMMC7721 and A549). Hoechst33258 and AO/EB staining showed HepG2 cells underwent the typical morphologic changes of apoptosis characterized by nuclear shrinkage, chromatin condensation, or fragmentation after exposure to quercetin nickel (II) complex. We also demonstrate that the levels of survivin and bcl-2 protein expression in HepG2 cells decreased concurrently, and the levels of p53 protein increased significantly after treatment with quercetin nickel (II) complex by immunocytochemistry analysis. The relative activity of caspase-3 and caspase-9 increased significantly after treatment with the complex. Furthermore, fluorescence measurements and molecular modeling were performed to learn that the complex could be preferentially bound to DNA in GC region. These results imply that quercetin nickel (II) complex may intercalate into the GC-rich core promoter region of survivin, down-regulating survivin gene expression and promoting tumor cells apoptosis. So our results suggest that antitumor activity of quercetin nickel (II) complex might be related to its intercalation into DNA and DNA-binding selectivity, and that the complex may be a promising agent for cancer therapy.

This study describes development of a novel controlled drug release system for multiple drugs, it consisted of Chitosan nanoparticles/PCL composite electrospun nanofibers with core-sheath structures. Two model agents' rhodamine B and naproxen were successfully loaded in the core and sheath region respectively. The behavior of these two agents demonstrated a good controlled release and temporality, providing a new way to obtain program or temporality release for multiple agents. Particularly, this is potential applications in the field of tissue engineering, sutures and wound dressings., (© 2010 Wiley-Liss, Inc. and the American Pharmacists Association)

More and more researchers are interested in DNA binders with sequence selectivity which may be developed to potential drugs. In this paper, we mainly review the compounds that selectively bind to special bases or sequences such as AT and GC-rich sequences. The selective binding of them to DNA sequences could affect the interactions of transcription factors with their target sequences in DNA. Furthermore, the design and effectiveness of sequence-selective DNA binding drugs are discussed. At last we put forward the some current challenges and solution in developing targeting anticancer drugs binding to specific oncogene., (Copyright 2010 Elsevier B.V. All rights reserved.)

Nanofibers with ordered patterns and architectures are critically important for many applications, including nanoscale device fabrication and tissue regenerations. During electrospinning process, the charge on a depositing nanofiber will become constant after the volatilization of solvent complete, which happens when the nanofibers get close to a collector that usually has a certain distance from the spinneret. In this case, the component forces acting on the depositing nanofibers that are arriving to a collector surfaces can be relatively analyzed based on the simulation results of the electrical field distribution on the collector. By using finite element method (FEM), in this study, the nanofiber deposition behavior including the orientation and alignment of nanofibers that are approaching to a collector were simulated and systematically investigated in term of the effects of electrostatic field applied to the collector. Based on the simulation results, we have experimentally demonstrated that Poly(epsilon-caprolactone) (PCL) nanofibers with various desired patterns and ordered architectures were prepared using predesigned collectors.

Agrimonia pilosa Ledeb is used as the tonic for asthenia and fatigue in China. Considering that the energizing effect might be correlated with antioxidant properties, we investigated the antioxidant activities of aqueous extract (AE) from Agrimonia pilosa Ledeb by assessing radical-scavenging and anti-lipid-peroxidation abilities. We found that AE shows a moderate antioxidant activity to scavenge DPPH*, O2(-)* and *OH and inhibit beta-carotene bleaching with IC(50) values of 13.0, 33.2, 351, and 11.9 microg/ml, respectively, while its AcOEt-soluble fraction (ESF) and BuOH soluble fraction (BSF) exhibit remarkable efficiencies. The ESF's IC(50) values of scavenging DPPH*, O2(-)*, and *OH, and inhibiting beta-carotene bleaching are 5.6, 5.8, 171, and 7.6 mircog/ml, respectively, and those of BSF are 7.5, 8.4, 82.0, and 6.2 microg/ml, respectively. In addition, we found that there is a significant correlation between total phenol content and the antioxidant activity determined by O2(-)* and *OH scavenging, and beta-carotene-bleaching assays. Furthermore, HPLC analysis revealed the presence of quercetin, hyperoside, quercitrin, taxifoliol, luteolin-7-O-beta-D-glucopyranoside, and rutin in Agrimonia pilosa Ledeb. Thus, we suggest that the extracts from Agrimonia pilosa Ledeb, could be considered as natural antioxidant sources and dietary nutritional supplements to prevent oxidation-related diseases.

The effects of conventional systemic chemotherapy are very modest, while the side-effects are very severe. Thus, intratumoral chemotherapy emerges as a new adjuvant treatment modality due to its several potential advantages. However, most researchers currently select only single cytotoxic drug as model drug at present studies, while ignore the combination administration. So, we hypothesize whether we can integrate the advantages of combination chemotherapy and intratumoral chemotherapy to achieve good antitumour effectiveness and minimal systemic side-effects and resistance. We propose that several drugs based on the cancer cell cycle are reserved in the microsphere-gel. Firstly, cell cycle specific agents (CCSA) are encapsulated into microspheres, then cell cycle non-specific agents and CCSA-loaded microspheres are dispersed into pre-gel solution. Eventually the goal of sequential, intermittent and combination chemotherapy is achieved. Therefore, the hypothesis has the potential application to treat cancer owing to its advantages of targeting effect, high efficiency, low side-effects and resistance, convenience.

Quercetin, a widely distributed bioflavonoid, has been shown to induce growth inhibition in a variety of human cancer cells. However, the regulation of survivin and Bcl-2 on the quercetin-induced cell-growth inhibition and apoptosis in cancer cells remains unclear. In the present study, we report that quercetin can inhibit proliferation and induce apoptosis in HepG2 cells in dose- and time-dependent manner. Hoechst 33258 and acridine orange/ethidium bromide (AO/EB) staining showed that HepG2 cells underwent the typical morphologic changes of apoptosis characterized by nuclear shrinkage, chromatin condensation, or fragmentation after exposure to quercetin. Cell-cycle analysis reveals a significant increase of the proportion of cells in G(0)/G(1) phase. We also demonstrate that the levels of survivin and Bcl-2 protein expression in HepG2 cells decreased concurrently, and the levels of p53 protein increased significantly after treatment with quercetin by immunocytochemistry analysis. Relative activity of caspase-3 and caspase-9 increased significantly. These data clearly indicate that quercetin-induced apoptosis is associated with caspase activation, and the levels of survivin and Bcl-2. Our results indicate that the expression of survivin may be associated with Bcl-2 expression, and the inhibition expression of survivin, in conjunction with Bcl-2, might cause more pronounced apoptotic effects. Together, concurrent down-regulated survivin and Bcl-2 play an important role in HepG2 cell apoptosis induced by quercetin.

The interaction of a quercetin nickel(II) complex with DNA was investigated using UV-vis spectra, fluorescence measurements, viscosity measurements, agarose gel electrophoresis and thiobarbituric acid-reactive substances assay. The results indicate that the quercetin nickel(II) complex can intercalate into the stacked base pairs of DNA, and compete with the strong intercalator ethidium bromide for the intercalative binding sites with Stern-Volmer quenching constant K(sq) = 1.0. The complex successfully promotes the cleavage of plasmid DNA, producing single and double DNA strand breaks. The amount of conversion of supercoiled form (SC) of plasmid DNA to the nicked circular form (NC) depends on the concentration of the complex, ionic strength and the duration of incubation of the complex with DNA. The maximum rate of conversion of the supercoiled form to the nicked circular form at pH 7.2 in the presence of 100 microM of the complex is found to be 0.76 x 10(-4) s(-1). The hydrolytic cleavage of DNA by the complex was supported by the evidence from free radical quenching and thiobarbituric acid-reactive substances assay.

Novel thermosensitive nano-micelles, based on Poly(D,L-lactide-co-glycolide)-b-poly(ethylene glycol)-b-poly(D,L-lactide-co-glycolide) (PLGA-PEG-PLGA), as carriers for drug delivery were researched. The critical micelle concentration of the copolymer in aqueous solution was determined to be 2.34 microgram/ml by fluorescence spectroscopy using pyrene as a fluorescence probe. The lower critical solution temperature (LCST) of the copolymer was measured in distilled water by optical transmittance, and the LCST was varied from 35 to 55 degrees C depending on polymer concentration. Acetaminophen as a model drug was loaded in nano-micelles by solvent evaporation method. In vitro acetaminophen release from micelles showed a sustained modality compared with the free drug as a control, and an obviously high release rate when temperature was increased above LCST. The studies showed that nano-micelles made from PLGA-PEG-PLGA could be ideal candidate carriers for tumor-special drug delivery.

The interaction of a quercetin copper(II) complex with DNA was investigated using UV-vis spectra, fluorescence measurement, viscosity measurement, agarose gel electrophoresis, and thiobarbituric acid reactive substances assay. The results indicate that the quercetin copper(II) complex can promote the cleavage of plasmid DNA, producing single and double DNA strand breaks, and intercalate into the stacked base pairs of DNA. Moreover, the complex can induce oxidative DNA damage involving generation of reactive oxygen species such as H(2)O(2) and Cu(I)OOH. In addition, the cytotoxicity experiments carried out with A549 cells confirmed its apoptosis-inducing activity. And we also demonstrate that the levels of survivin protein expression in A549 cells decreased, and that relative activity of caspase-3 increased significantly after treatment with the complex. So our results suggest that the antitumor mechanism of the quercetin copper(II) complex involves not only its oxidative DNA damage with generation of reactive oxygen species but also its specific interaction with DNA.

Silk fibroin from the silkworm, Bombyx mori, has excellent properties such as biocompatibility, biodegradation, non-toxicity, adsorption properties, etc. As a kind of ideal biomaterial, silk fibroin has been widely used since it was first utilized for sutures a long time ago. The degradation behavior of silk biomaterials is obviously important for medical applications. This article will focus on silk-based biomaterials and review the degradation behaviors of silk materials.

Using a stainless steel mesh as a template collector, electrospun nanofiber meshes with well-tailored architectures and patterns were successfully prepared from biodegradable poly (epsilon-caprolactone) (PCL). It was found that the resulting PCL nanofiber (NF) meshes had similar topological structures to that of the template stainless steel mesh. Such PCL nanofiber meshes (NF meshes) had improved the tensile strength with Young's modulus of 62.7 +/- 5.3 MPa, which is >40% higher than the modulus of 44 +/- 5.7 MPa as measured with the corresponding randomly oriented PCL nanofiber mats (RNF mat). On the other hand, the ultimate strain (87.30%) of the PCL NF meshes was distinctly lower than that of the PCL RNF mats (146.46%). To the best of our knowledge, this is the first time that the mechanical properties of nanofiber meshes with tailored architectures and patterns were studied and reported. When cultured with a mouse osteoblastic cell line (MC3T3-E1), the electrospun PCL NF meshes gave a much higher proliferation rate as compared with the randomly oriented PCL RNF mats. More importantly, it was found that the cells grew and elongated along the fiber orientation directions, and the resulted cellular organization and distribution mimicked the topological structures of the PCL NF meshes. These results indicated that the electrospun nanofiber scaffolds with tailored architectures and patterns hold potential for engineering functional tissues or organs, where an ordered cellular organization is essential.

While the role of hemostatic activity is well established, the importance of infection prevention in the wound has not been addressed. Based on the available evidence from disinfection and infection prevention, essential oils are attractive candidates for antimicrobial drugs. Therefore, we hypothesize to design a novel hemostatic model with triple protective functions through coordinating essential oils to hematostatic ingredients. The hematostatic ingredients play their roles in hemostasis when hemorrhage occurs. Simultaneously, the essential oils evaporate naturally to form a protective layer around the wound, which can help to prevent pathogenic bacteria from infecting the wound. What more, most plant essential oils possess antibacterial activity. Thus, the essential oils can be used as an accessory treatment for infection once the wound infected by pathogenic bacteria. So the novel hematostatic model with triple protective functions will have broader utility in therapy of out-wound bleeding than current hemostatic drugs.

DNA cleavage activity of quercetin zinc(II) complex has been studied, but little attention has been devoted to the relationship between antitumor activity of this complex and DNA-binding properties. DNA-binding properties of quercetin zinc(II) complex were studied using UV-vis spectra, fluorescence measurements, and viscosity measurements. The results obtained indicate that quercetin zinc(II) complex can intercalate into the stacked base pairs of DNA, and compete with the strong intercalator ethidium bromide for the intercalative binding sites with Stern-Volmer quenching constant, K(sq)=1.24. The complex was subjected to biological tests in vitro using three tumor cell lines (HepG2, SMMC7721, and A549), which showed significant cytotoxicity against three tumor cell lines. Moreover, Hoechst33258 staining showed HepG2 cells underwent the typical morphologic changes of apoptosis characterized by nuclear shrinkage, chromatin condensation, or fragmentation after exposure to the complex. In addition, Molecular modeling was performed to learn the complex could be preferentially bound to DNA in GC region. Our results suggest that antitumor activity of quercetin zinc(II) complex might be related to its intercalation into DNA.

Recently, TDDS (Targeting drug delivery system) plays an important role in enhancing the bioavailability and targeting of anti-tumor drugs. How to transport drugs quickly and precisely to their target sites of action has not been solved fundamentally. A large number of researches have identified artemisinin and its analogs have the merit of precisely targeting to cancer cell, and low side effects to healthy tissue. Thus, if these compounds could be attached to established anti-tumor drugs with probe, a novel targeting anti-tumor drugs will be put into practice in the future. The novel drugs delivery system will be a powerful weapon against cancer disease for their unique targeting.

Micelle is a stable, passively targetable and solubilizing minute particle, and plays a key role to anticancer drug delivery for chemotherapy. With an increasing number of novel polymeric micelles synthesized, many anticancer drugs have been core-encapsulated in the micelles. However, only single drug was studied as the model drug at present researches. It is well known that combined medication is a very important and common method for chemotherapy in the clinic. Therefore, we hypotheses that multi-anticancer drugs encapsulated in the micelle may be proposed based on the cancer cell cycle. Briefly, cell cycle specific agents are chemically conjuncted into the micelles firstly, and then cell cycle non-specific agents are physically loaded in the compound of drugs and micelles. Thus combined administration using micelles as drug carriers is achieved. This hypothesis integrates advantages of the nano-micelles at present researches and drug combination in the clinic. So, it presents many merits for drug delivery, such as high efficiency, convenience and anti-resistance.

Recently, the concept of drug delivery requires that the release of encapsulated drug be produced only at the diseased site with controllable rates. Given that thermosensitive hydrogels have been widely investigated for controlled delivery based on their phase transition, we speculate that nanoparticles with the novel polymers play a key role in tumor therapy respond to thermal activity. Therefore, we here hypothesize that enhanced delivery of therapeutics might be achieved by conjugation to thermosensitive polymers, in concert with targeted hyperthermia by precisely specifying the phase transition temperature of the thermosensitive polymer. By local hyperthermia at tumor site, a targeted drug delivery system could be obtained, exploiting both the temperature-sensitive and the site-specific behaviors. The proposition may provide a new strategy into the development of a novel drug delivery system for tumor therapy.

The effect of sound wave stress on important medicinal plant, Dendrobium candidum Wall. ex Lindl, was investigated, including the responses on malondialdehyde (MDA) content, the activities change of superoxide dismutase (SOD), catalase (CAT), peroxidase (POD) and ascorbate peroxidase (APX). Results were found that the activities of SOD, CAT, POD and APX enhanced totally in different organs of D. candidum, as leaves, stems and roots, in response to the stress. Furthermore there happened similar shift of antioxidant enzymes activities, which increased in the initial stimulation and decreased afterwards. Data showed SOD, CAT, POD and APX activities ascended to max at day 9, 6, 9 and 12 in leaves, at day 9, 6, 12 and 9 in stems, and at day 12, 6, 9 and 9 in roots, respectively. As a lipid peroxidation parameter, MDA content in different organs increased in the beginning, dropped afterward, and increased again in the late. Anyway the total trend was the rise of MDA level compared to the control. It was interesting that the MDA content appeared the lowest levels almost when the antioxidant enzymes activities were up to the highest. Our results demonstrated the different organs of D. candidum might produce accumulation of active oxygen species (AOS) under initial treatment of sound wave stress. Later AOS might start to reduce due to the enhancement of antioxidant enzymes activities treated by the stress. The data revealed that the antioxidant metabolism was to be important in determining the ability of plants to survive in sound stress, and the up regulation of these enzymes activities would help to reduce the build up of AOS, which could protect plant cells from oxidative damage. Moreover, different cell compartments might activate different defensive system to reduce excessive amount of AOS. Finally the mechanism of this action was also discussed simply.

In this study, we determined the protective effect of total flavonoids from Spirodela polyrrhiza (L.) Schleid (STF), which is a kind of traditional Chinese medicine, on human umbilical vein endothelial cells (ECV-304) damage induced by hydrogen peroxide (H(2)O(2)). Treated with 1mmol/L H(2)O(2) for 1h, the viability of ECV-304 cells markedly decreased. However, pretreatment with 10-50mug/mL STF resulted in a significant recovery. The survival rate of ECV-304 increased from 21.98% (only treated with 1mmol/L H(2)O(2)) to 64.74% (pretreated with 50microg/mL STF), which accompanied with the amounts of malondialdenhyde (MDA) decreasing from 1.6883nmol/L to 0.9628nmol/L. Furthermore, compared with control group, the 50mumol/L STF pretreatment enhanced the total antioxidant capacity (T-AOC) by 4.49 times, increased the activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX) by 85.12%, 158.94% and 94.5%,respectively, and increased the content of nitric oxide (NO) by 116.55%. Taken together, STF protect ECV-304 cells against H(2)O(2) damage by enhancing the antioxidant ability and increasing NO production.

In this paper, we studied the naphthalene degradation by using Pseudomonas aeruginosa under low-intensity ultrasonic stimulation. In our experiment, the degradation rate of naphthalene was the main parameter. We found that low-intensity ultrasonic could not only promote the growth of immobilized P. aeruginosa, but also could improve the degradation of naphthalene. In this article, 1% naphthalene was added into MM culture medium as imitation wastewater. The effect of low-intensity ultrasonic parameter and gel-globes size were considered. We found the influence was obvious, and the optimum degradation rate was acquired when the parameters of ultrasonic are: frequency, 24 kHz; power, 8 W; ultrasonic time, interval time, 10 s; total time, 10 m and the gel-globes were made by using injector no. 14. The naphthalene degradation rate of immobilized cells with ultrasonic stimulation is 82%, which is 12.9 and 42.2% higher than that of immobilized cells and suspended cells without ultrasonic stimulation, respectively.

Based on the assumed flat model, Navier-Stokes equation for two-dimensional laminar flow fluid and the theory for diffusion and mass transfer, we obtained theoretical results with regarding to the concentration distribution in separation process by mass transfer model in the ultrafiltration process. Through theoretical analysis and experimental verification of concentration distribution, it was known that this model could not only preferably describe the concentration distribution of ultrafiltration process but also forecast concentration polarization phenomenon.

A method of the transformed hairy roots cultures of Echinacea purpurea was established by infecting different types of explants with three type strains of Agrobacterium rhizogenes (A4, R1601 and R1000) in this paper. We obtained that the transformed percentage of E. purpurea leaves with A4, R1601 and R1000 were 80%, 60%, 40%, respectively and that of E. purpurea leafstalks were 10%, 30%, 45%, respectively. The contents of polysaccharides and phenolic compounds were measured in transformed hairy roots and non-transformed roots after 2 months in culture. For transformed hairy roots, the contents of polysaccharides and phenolic compounds were 236.0 and 18.9 mg g(-1) DW, respectively. While the contents of polysaccharides and phenolic compounds in non-transformed roots were 161.5 and 33.3 mg g(-1) DW, respectively.

RNA isolation is a prerequisite to the study of gene expression of herbaceous plant Dendrobium nobile under an environmental stress. However, RNA isolation is difficult in the plant of genus Dendrobium, which is relatively viscous, due to being rich in polysaccharides. The common protocols for RNA isolation are tedious and usually result in poor yields when applied to D. nobile. Here, we describe a simple and convenient method for high quality total RNA extraction from D. nobile. Main procedures are as follows: smashing plant tissue and cell wall by means of pre-cooled citrate homogenization, cleaving cell membrane by using guanidine hydrochloride lysis buffer, removing proteins, polyphenols and polysaccharides by acidic phenol/chloroform. It is particularly useful for processing large numbers of plant samples. The whole process can be completed within 2.5 h. The extracted RNA is suitable for applications such as RT-PCR, Northern analysis and screening of differential expression genes.

The ability to apply controllable mechanical compressive force is essential for the study of plant cells responses to environmental stimulations. The work presented here aims towards establishing a system, which consists of a fabricated apparatus (including a loading unit, displacement sensor, data collector and processor, and a feedback control) and a protocol for test specimen preparation and force loading. By using a force-feedback control circuit coupled to a microchip, delivering the pre-defined and actual controlled stimulus is achieved. To calibrate the apparatus, the corresponding voltages are compared to the known weights. A linear regression is fit to the experimental data and a standardized coefficient of 0.998 is calculated. The morphological changes in response to mechanical stresses were investigated in agarose gel embedded chrysanthemum protoplasts, which tended to be elongated with a preferential axis oriented perpendicularly to the compressive stress direction. The results also indicated that there existed a certain dose-dependent relationship between the intensity of compressive force and the stress-induced responses. Additionally, the elongation response with preferential orientation was inhibited by application of RGD peptides, and its inverted sequence, DGR peptides failed to antagonize the effect of mechanical force on elongation performance.

When pathogens penetrate plant cells, some chemical secretions are elicited, and the mechanical signals in plant cell may be induced by the simultaneous physical pressure to change. Based on the previous cognitions, we investigated the plant resistance and the variation of anti-disease enzyme activity in cucumber leaves after mechanical stress loading. Results showed that the appropriate mechanical stimulation could significantly improve plant resistance and alter the activity of phenylalanine ammonial lyases (PAL) and POD, leading to synthesis of lignin. However, we found that the effects of the stress on these cellular fundamental events were eliminated when the adhesion between plasma membrane and cell wall was disrupted. We speculated that mechanical signal transduction in plants depend on the adhesion of plasma membrane-cell wall.

This paper describes the preparation and characterization of a novel drug delivery system for protein, liposomes-in-alginate (LIA) of biodegradable polymers, which is conceived from a combination of the polymer and the lipid-based delivery systems. LIA were prepared by first entrapping bovine serum albumin (BSA), a model protein within multivesicular liposomes (MVLs) by double emulsification process, which are then encapsulated within alginate hydrogel microcapsule, with untrapped BSA which are added during preparation of MVLs. Factors impacting encapsulation efficiency of MVLs are investigated and release of protein from the microcapsules in vitro is studied. At the same time, characterization of MVLs, microcapsules encapsulated protein formulation and integrality analyse of BSA in microcapsules are also studied, with the aim of improving the entrapment efficiency and prolonging release time. It is found that encapsulation efficiency and size of MVLs are affected by the composition and fabrication parameters of LIA. The data also show LIA have high encapsulation efficiency (up to 95%), little chemical change in drug caused by the formulation process, narrow particle size distribution and spherical particle morphology. Drug release assays conducted in vitro indicates that these formulations provide sustained release of encapsulated drug over a period, about 2 weeks.

An efficient approach was described for the culture of protoplasts isolated from chrysanthemum, and factors affecting the plating efficiency, defined as the number of protoplasts developing microcolonies divided by the number of cultured protoplasts, were investigated here. A yield of 4.86+/-0.22x10(5) mesophyll protoplasts per gram fresh weight were achieved by an enzymolysis procedure. The viability of fresh isolated protoplasts was 64.5+/-8.2% as confirmed by Evans blue staining. Sustained cell division and microcolony formation from the protoplasts were supported by modified Murashige and Skoog medium, complemented with 1:4 diluted conditioned medium harvested from three different callus suspension cultures. Results showed that the plating efficiency was obviously influenced by various concentrations of agarose and antibiotic, and significantly increased by conditioned medium harvested from chrysanthemum suspensions, while the other two species had a positive effect generally. Results also indicated that the growth-stimulative effect was reduced when the conditioned medium was stored for 6-14 days prior to use, suggesting the unstable characteristic of conditioning factors.

The tetrazolium salt 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) is used to determine cell viability in assays of cell proliferation and cytotoxicity. MTT is reduced in metabolically active cells to yield an insoluble purple formazan product. However, in this study, using a colorimetric method with MTT, we demonstrated that luteolin and quercetin (both are flavonoids) can reduce MTT in the absence of living cells. We also examined effects of some experimental conditions on the reaction, such as concentrations of flavonoids, incubation time, the structure and the existing form in solvents of flavonoids. The maximal absorbance values, which were 0.355 (luteolin) and 0.491 (quercetin), were observed when the concentrations of flavonoids were 200 microg/ml. Incubating MTT with flavonoids for 8 h, the absorbance values got the maximum, which were 0.320 (luteolin) and 0.398 (quercetin). The ability of flavonoids reducing MTT in RPMI-1640 with 10% fetal calf serum was higher than that in anhydrous ethanol. And the ability of quercetin reducing MTT was higher than that of luteolin both in RPMI-1640 with 10% fetal calf serum and anhydrous ethanol. Based on the results, this undescribed reaction can significantly influence the results of experiments using the MTT assay to measure the effects of flavonoids on cell growth.

The triorganotin 2-phenyl-1,2,3-triazole-4-carboxylates, 2-PhC2N3CO2SnR3 (R=C6H5, 1; c-C6H11, 2; C6H5C(CH3)2CH2, 3), have been prepared and characterized by means of elemental analysis, IR and NMR (1H, 13C and 119Sn) spectroscopy. The crystal structures of 1 and 3 have been determined. Compound 1 is polymeric in nature with a trigonal bipyramidal configuration, and compound 3 shows a tetrahedral geometry. Bioassay results have shown that these compounds have good antibacterial and antitumor activity. The activity against three human tumor cell lines (HeLa, CoLo205 and MCF-7) decreased in the order 1>2>3.

Inducer can induce new active composition and increase the content of the active composition in the plant. In this paper, we investigated the synthesis and accumulation of phytoalexin in cucumber seedlings which were induced by chemical inducer of the salicylic acid (SA) and physical inducer. Analyzed by experiment of antifungal activity, thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC), the result was that both SA and stress can induce the synthesis and accumulation of phytoalexin in cucumber seedlings. But the content of phytoalexin induced by SA was lower than it induced by stress. And in this paper, another conclusion was that the transduction of physical signal and the chemical signal in the plant depended on the adhesion between cell wall and plasma and active oxidative species producted by stimulation.

During the course of pathogens penetrating the plant cell, besides of chemical secretion, the pathogens may cause mechanical signal by the physical pressure on the plant cell. In the current study, we took the stress as the mechanical signal elicitor to find the effect of plant resistance induced by stress. The results showed that an appropriate stress stimulation can evidently improve the plant resistance. However, disruption the plasma membrane-cell wall adhesion will absolutely eliminate this kind of inducement effect, which suggests that the plant resistance inducement by stress depend on the adhesion of plasma membrane-cell wall. Also we found that stress stimulation may cause synthesis of lignin and increase the activity of phenylalaninc ammonial lyase (PAL) chitinase and beta-1,3-glucanase obviously. The results showed that stress stimulation may not only enhance ability of the plant cell resistant to pathogen penetration but also elicit the accumulation of pathogens suppression or antimicrobial chemical substance in the plant cell.

A new type of drug delivery system that microcapsule was prepared by liposome in alginate on this paper, bovine serum albumin (BSA) as an model drug. Influences of liposomes composition and multivalent cations on morphology, enveloped rate, integrality and release in vitro from microcapsule were investigated. The results are showed that Ca2+ and Ba2+ made hydrogels form easier than Al3+ and particle size were uniform, circular, but microcapsule prepared by Al3+ was flat circular and easily adhere to each other. Particle size of all microcapsules was 200-300 microm after dryness, measured by vernier calliper. BSA enveloped rate prepared by PC/PG/Chol and Ba2+ was highest, 77.65%, and also correlative to concentration of lipid. At the other hand, Ba2+ microcapsule prepared by liposome in alginate has not an initial burst and have a good performance on delivering protein. Integrality of protein was not destroyed after encapsulated.

Many methods were used to devise peptide and protein drugs delivery system (DDS). Because of their relatively large size, they have low transdermal bioavailabilities. In systemic delivery of proteins, biodegradable material as parenteral depot formulation occupy an important place because of several aspects like protection of sensitive proteins from degradation, prolonged or modified release, pulsatile release patterns. The main objective in developing controlled release protein injectables is avoidance of regular invasive doses which in turn provide patient compliance, comfort as well as control over blood levels. This review article presents the outstanding contributions in field of microencapsulation as protein delivery systems and different approaches of protein delivery are described. Then discusses how these advances may be applied to resolve the challenges face the development of microcapsule for the controllable delivery of protein drugs.

To investigate expression of integrin beta1 and its roles on adhesion between different cell cycle hepatocellular carcinoma cell (HCC) and human umbilical vein endothelial cells (HUVEC), the synchronous G1 and S phase HCC were achieved through thymine-2-deoxyriboside and colchicines sequential blockage method and double thymine-2-deoxyriboside blockage method, respectively. Expression of integrin beta1 on hepatocellular carcinoma cells was detected with flow cytometer. Further, the adhesive force of HCC to HUVEC and the role of integrin beta1 in this adhesive course were studied by micropipette aspiration technique. The results showed that percentage of each cyclic phases of the controlled HCC (non-synchronous) are: G2 + M phase, 11%; G1 phase, 54%; S phase, 36%; the synchronous rates of G1 and S phase HCC amount to 74 and 98%, respectively. The expressive fluorescent intensity of integrin beta1 in G1 phase HCC is depressed significantly than the values of S phase and controlled HCC. Accordingly, the adhesive forces of G1 phase HCC to HUVEC was significantly lower than the value of S phase cells (P < 0.01), but it has no remarkable difference when compared the adhesive force values of S phase HCC with control; the contribution of integrin beta1 was about 50% in the adhesion of HCC to HUVEC. It suggested that HCC would be synchronized preferably in G1 and S phase with thymine-2-deoxyriboside and colchicines, the adhesive molecule integrin beta1 expressed in a high lever in HCC and presented differences in vary cell cycle, and integrin beta1 played an important roles in adhesion of HCC to HUVEC. Possibly, S phase HCC take a great action in this adhesive course.