Prediction of Energy Storage Performance in Polymer Composites Using High-Throughput Stochastic Breakdown Simulation and Machine Learning.

Polymer dielectric capacitors are widely utilized in pulse power devices owing to their high power density. Because of the low dielectric constants of pure polymers, inorganic fillers are needed to improve their properties. The size and dielectric properties of fillers will affect the dielectric breakdown of polymer-based composites. However, the effect of fillers on breakdown strength cannot be completely obtained through experiments alone. In this paper, three of the most important variables affecting the breakdown strength of polymer-based composites are considered: the filler dielectric constants, filler sizes, and filler contents. High-throughput stochastic breakdown simulation is performed on 504 groups of data, and the simulation results are used as the machine learning database to obtain the breakdown strength prediction of polymer-based composites. Combined with the classical dielectric prediction formula, the energy storage density prediction of polymer-based composites is obtained. The accuracy of the prediction is verified by the directional experiments, including dielectric constant and breakdown strength. This work provides insight into the design and fabrication of polymer-based composites with high energy density for capacitive energy storage applications.

Serum vitamin E concentration is negatively associated with body mass index change in girls not boys during adolescence.

BACKGROUND: Vitamin E is the most abundant lipid-soluble antioxidants present in plasma; however, the relationship between serum vitamin E and change in body mass index (BMI)-for-age Z scores in adolescents has not been well described. METHODS: This study is a cross-sectional study. Data were analyzed from 4014 adolescents who participated in the National Health and Nutrition Examination Survey. The nutritional status was calculated by BMI Z scores and was classified into normal weight, overweight, and obese. Multivariable-adjusted logistic regression was used to examine the association between serum vitamin E levels with overweight/obesity. Besides, the interaction effects between potential confounders and vitamin E on obesity were further evaluated. RESULTS: After adjusting potential confounders, serum vitamin E levels were negatively associated with overweight/obesity in girls but not in boys. Per standard deviation increment in vitamin E concentrations was associated with a 92% decreased risk of obesity in females. Besides, lower quartiles of serum vitamin E were associated with a higher risk of overweight/obesity in girls. Moreover, the inverse association between serum vitamin E levels and obesity was also found in most subgroups through subgroup analysis. CONCLUSIONS: Our study supports the negative association between serum vitamin E levels and overweight/obesity in adolescents. A higher serum vitamin E level may be associated with a reduced probability of obesity in girls, but not in boys.

Strategy for the Construction of Diverse Poly-NHC-Derived Assemblies and Their Photoinduced Transformations.

A series of supramolecular assemblies of types [Ag8 (L)4 ](PF6 )8 and [Ag4 (L)2 ](PF6 )4 , obtained from the tetraphenylethylene (TPE) bridged tetrakis(1,2,4-triazolium) salts H4 -L(PF6 )4 and AgI ions, is described. The assembly type obtained dependends on the N-wingtip substituents of H4 -L(PF6 )4 . Changes in the lengths of the N4-wingtip substituents enables controlled formation of assemblies with either [Ag4 (L)2 ](PF6 )4 or [Ag8 (L)4 ](PF6 )8 stoichiometry. The molecular structures of selected [Ag8 (L)4 ](PF6 )8 and [Ag4 (L)2 ](PF6 )4 assemblies were determined by X-ray diffraction analyses. While H4 -L(PF6 )4 does not exhibit fluorescence in solution, their tetra-NHC (NHC=N-heterocyclic carbene) assemblies do upon NHC-metal coordination. Upon irradiation, all assemblies undergo a light-induced, supramolecule-to-supramolecule structural transformation by an oxidative photocyclization involving phenyl groups of the TPE core, resulting in a significant change of the luminescence properties.

A Mechanism Study of Electroacupuncture for Dry Eye Syndrome by Targeting Conjunctival Cytokine Expressions.

Aim: To discuss the immunological mechanism in electroacupuncture (EA) treatment of dry eye syndrome (DES) by targeting the changes in conjunctival cytokine expression profile.Method: Eligible DES patients were randomized into an EA group (EAG) or an acupuncture group (AG). The ocular surface disease index (OSDI), amount of tear production, and tear film break-up time (BUT) were observed to evaluate the efficacy. Conjunctival cells were collected from both effective and invalid cases to observe the expressions of cytokines by protein microarray. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) were used for functional cluster and signaling pathway analysis of the differentially expressed proteins. Enzyme-linked immunosorbent assay (ELISA) was used to verify the specific differential proteins.Result: After treatment, OSDI dropped and BUT extended in both groups, and the tear production increased only in the EAG (all P < .01). Compared with the AG, the improvement in tear production was more significant in the EAG (P < .01). There were 17 differentially expressed conjunctival cytokines between the effective and invalid cases in the EAG, and those expressed higher than the limit of detection (LOD) included monocyte chemoattractant protein 1 (MCP-1), macrophage colony-stimulating factor (M-CSF), regulated on activation in normal T-cell expressed and secreted (RANTES) and tissue inhibitor of metalloproteinases 1 (TIMP-1). GO analysis showed that the differential cytokines were mainly involved in cellular interaction, signaling pathways and reactions to stimuli. KEGG analysis revealed that the signaling pathways of these cytokines were mainly responsible for interactions between cytokines or between cytokines and their receptors, such as Jak-STAT signaling pathway, chemokine signaling pathway, and tumor necrosis factor signaling pathway.Conclusion: EA can effectively treat DES by improving the symptoms, increasing tear secretion and extending BUT, which is possibly related to its regulation on the conjunctival cytokine expressions.

Knockdown of Tripartite Motif-Containing Protein 37 (TRIM37) Inhibits the Proliferation and Tumorigenesis in Colorectal Cancer Cells.

Tripartite motif-containing protein 37 (TRIM37), a new member of the RING-B-box-coiled-coil (RBCC) subfamily of zinc finger proteins, was found to be involved in the development and progression of several cancers. However, the expression pattern and biological functions of TRIM37 in colorectal cancer (CRC) remain unknown. Therefore, in the present study, we examined the expression pattern of TRIM37 in CRC and investigated the function of TRIM37 in the progression of CRC. Our results showed that TRIM37 expression was upregulated in CRC cell lines. Knockdown of TRIM37 inhibited CRC cell proliferation and tumor growth in vivo. Furthermore, knockdown of TRIM37 inhibited the migration and invasion in CRC cells. Last, knockdown of TRIM37 inhibited the protein level expression of ß-catenin, cyclin D1, and c-Myc in CRC cells. In conclusion, these results demonstrate that TRIM37 may play an important role in the proliferation, invasion, and tumorigenesis of CRC cells. Thus, TRIM37 may be a potential therapeutic target for the treatment of CRC.

[Study on Nonlinear Spectral Properties of Photonic Crystal Fiber in Theory and Experiment].

Photonic crystal fiber can generate particular dispersion properties and highly nonlinear, because of the special guiding mechanism and the adjustable structure parameters，which provides new conditions for the study of nonlinear fiber optics. There are rich nonlinear spectral properties produced by a variety of nonlinear physical effect, under different pump light pulse parameters in photonic crystal fibers with different structure and transmission properties. At present many papers have reported the experimental results of nonlinear optical properties in photonic crystal fiber, but there is little theoretical analysis about the produced mechanism and the change rule of the nonlinear spectrum. In the paper, solving nonlinear Schrodinger equation with split-step Fourier method, transmission process of femtosecond laser pulse in photonic crystal fiber is simulated. The relationship between the output spectrum and incident light pulse parameters (the peak power of pump light P, the wavelength of pump light λ, the shape of light pulse, the width of light pulse TFWHM), the structure parameters of optical fiber (the pitch Λ, the hole-to-pitch ratio d/Λ, the length of fiber), the transmission characteristics (the dispersion properties, the nonlinear coefficient) is obtained. The spectral characteristics produced by nonlinear effects of the Raman soliton, dispersive wave, self-phase modulation are analyzed. The nonlinear optical spectrum of cladding note in photonic crystal fiber is studied in experiments, the broadband spectrum of soliton wave and dispersive wave is obtained. There are blue-shift dispersive wave near the wavelength of 0.5 µm, residual pump light near the wavelength of 0.82 µm, soliton wave near the wavelength of 1.1 µm, red-shift broadband dispersion wave near the wavelength of 2 µm in the spectrum obtained both in theory and experiment. The numerical simulation is confirmed through experimental observation. The physics principle of the nonlinear spectrum in photonic crystal fiber is revealed. These are useful and practical to realize the controllable output of broadband spectrum. These provide guidance for the structure design, fabrication, applied research of high nonlinear photonic crystal fiber.

Knockdown of SPOCK1 Inhibits the Proliferation and Invasion in Colorectal Cancer Cells by Suppressing the PI3K/Akt Pathway.

Sparc/osteonectin, cwcv, and kazal-like domains proteoglycan (testican) 1 (SPOCK1), known as testican-1, were found to be involved in the development and progression of tumors. However, in colorectal cancer (CRC), the expression pattern of SPOCK1 and its functional role remain poorly investigated. In the present study, we explored the role of SPOCK1 in CRC. Our results demonstrated that SPOCK1 is overexpressed in CRC cell lines. SPOCK1 silencing significantly inhibited the proliferation in vitro and the tumor growth in vivo. Furthermore, SPOCK1 silencing significantly attenuated the migration/invasion by reversing the EMT process in CRC cells. Finally, knockdown of SPOCK1 obviously decreased the protein expression levels of p-PI3K and p-Akt in HCT116 cells. In total, our study demonstrated for the first time that knockdown of SPOCK1 inhibits the proliferation and invasion in CRC cells, possibly through the PI3K/Akt signaling pathway. Therefore, SPOCK1 may be a potential therapeutic target for the treatment of CRC.

Quantitative Assessment of the Association between Genetic Variants in MicroRNAs and Colorectal Cancer Risk.

BACKGROUND: The associations between polymorphisms in microRNAs and the susceptibility of colorectal cancer (CRC) were inconsistent in previous studies. This study aims to quantify the strength of the correlation between the four common polymorphisms among microRNAs (hsa-mir-146a rs2910164, hsa-mir-149 rs2292832, hsa-mir-196a2 rs11614913, and hsa-mir-499 rs3746444) and CRC risk. METHODS: We searched PubMed, Web of Knowledge, and CNKI to find relevant studies. The combined odds ratio (OR) with 95% confidence interval (95% CI) was used to estimate the strength of the association in a fixed or random effect model. RESULTS: 15 studies involving 5,486 CRC patients and 7,184 controls were included. Meta-analyses showed that rs3746444 had association with CRC risk in Caucasians (OR = 0.57, 95% CI = 0.34-0.95). In the subgroup analysis, we found significant associations between rs2910164 and CRC in hospital based studies (OR = 1.24, 95% CI = 1.03-1.49). rs2292832 may be a high risk factor of CRC in population based studied (OR = 1.18, 95% CI = 1.08-1.38). CONCLUSION: This meta-analysis showed that rs2910164 and rs2292832 may increase the risk of CRC. However, rs11614913 polymorphism may reduce the risk of CRC. rs3746444 may have a decreased risk to CRC in Caucasians.

[Study on phase-matching of four-wave mixing spectrum in photonic crystal fiber].

In the present paper, the four-wave mixing principle of fiber was analyzed, and the high-gain phase-matching conditions were shown. The nonlinear coefficient and dispersion characteristics of photonic crystal fibers were calculated by multipole method. The phase mismatch characteristics of fibers with multiple zero-dispersion wavelengths were analyzed for the first time. The changing rules of phase matching wavelength with the pump wavelength and the pump power were obtained, and the phase matching curves were shown. The characteristics of phase matching wavelengths for different dispersion curves were analyzed. There are four new excitation wavelengths of four-wave mixing spectrum in two zero-dispersion wavelength photonic crystal fiers. Four-wave mixing spectroscopy of photonic crystal fibers with two zero-dispersion wavelengths was obtained in the experi-ent, which is consistent with the theoretical analysis, and verified the reliability of the phase matching theory. The fiber with multiple zero-dispersion wavelengths can create a ricbhphase-matching topology, excite more four-wave mixing wavelengths, ena-ling enhanced control over the spectral locations of the four-wave mixing and resonant-radiation bands emitted by solitons and short pulses. These provide theoretical guidance for photonic crystal fiber wavelength conversion and supercontinoum generation based on four-wave mixing.

Association between genetic polymorphisms in AURKA (rs2273535 and rs1047972) and breast cancer risk: a meta-analysis involving 37,221 subjects.

BACKGROUND: Published data on the association between AURKA polymorphisms and breast cancer (BC) risk are inconclusive. This meta-analysis was performed to derive a more precise estimation on the relationship between AURKA polymorphisms (rs2273535 and rs1047972) and BC risk. METHODS: PubMed, Web of Knowledge and Embase were searched for relevant studies. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to estimate the strength of associations. The pooled odds ratios (ORs) with 95% confidence intervals (CIs) were performed for allele contrast genetic model, homozygous genetic model, heterozygote genetic model, dominant model, and recessive model, respectively. RESULTS: A total of 13 studies (16,349 BC patients and 20,872 case-free controls) were involved in this meta-analysis. Meta-analysis showed that there was significant association between rs2273535 and BC risk in three genetic models in the overall population (A vs. T: OR = 1.08, 95% CI = 1.01-1.15, P = 0.02; AA vs. TT: OR = 1.36, 95% CI = 1.06-1.73, P < 0.00001; AA vs. TT + TA: OR = 1.15, 95% CI = 1.01-1.31, P = 0.04). In the subgroup analysis by ethnicity, the effects remained in Asians (allele contrast genetic model: OR = 1.12, 95% CI = 1.00-1.26, P = 0.04 and homozygote comparison: OR = 1.22, 95% CI = 1.06-1.41, P = 0.007). However, no genetic models reached statistical association in Cauasians. Rs1047972 polymorphism was associated with BC risk in the overall population based on homozygote comparison (AA vs. GG: OR = 0.81, 95% CI = 0.66-0.99, P = 0.04). When stratified by ethnicity, rs1047972 polymorphism had a decreased association with BC risk in Caucasians based on allele contrast genetic model, homozygote comparison, the dominant model and the recessive model. However, there was no association in any genetic model in Asians. CONCLUSIONS: This meta-analysis suggests that AURKA rs2273535 polymorphism has an increased risk with BC, especially in Asians. However, rs1047972 polymorphism has a decreased BC risk in Caucasians. Further large scale multicenter epidemiological studies are warranted to confirm this finding.

Effects of interleukin-10 polymorphisms (rs1800896, rs1800871, and rs1800872) on breast cancer risk: evidence from an updated meta-analysis.

BACKGROUND: The associations between Interleukin-10 (IL-10) polymorphisms and breast cancer (BC) risk are inconsistent. This study was aimed to evaluate the relationship between IL-10 polymorphisms (rs1800896, rs1800871, and rs1800872) and BC risk. METHODS: Databases, including PubMed, Web of Knowledge, Embase, and Chinese National Knowledge Infrastructure, were searched to find relevant studies. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to estimate the strength of associations. RESULTS: A total of 12 studies (4743 cancer cases and 5120 case-free controls) were eligible for meta-analysis. There were nine studies with 1851 cases and 1910 controls for rs1800896, six studies with 1034 cases and 1173 controls for rs1800871, and seven studies with 3637 cases and 3391 controls for rs1800872. Meta-analysis showed that rs1800896 and rs1800871 polymorphisms had no association with BC risk (for rs1800896: OR=1.060, 95% CI=0.785-1.432 in the dominant model, and OR=1.152, 95% CI=0.958-1.386 in the recessive model; for rs1800871: OR=0.952, 95% CI=0.859-1.056 in the dominant model, and OR=0.892, 95% CI=0.741-1.072 in the recessive model). However, rs1800872 polymorphism has association with BC risk based on the recessive model (OR=0.80, 95% CI=0.73-0.88). In the stratified analysis, when analyzed by the recessive model (CC vs. AA+AC), the ORs were 0.75 (95% CI=0.68-0.83) (p<0.00001) among Caucasians and 1.17 (95% CI=0.88-1.55) (p=0.27) among Asians. These results suggested that the CC homozygote has a 25% decreased risk of BC compared with those individuals with AA and AC genotypes in Caucasians. CONCLUSIONS: This meta-analysis showed that IL-10 rs1800896 and rs1800871 polymorphisms had no association with BC risk, while rs1800872 polymorphism had a decreased risk of BC in Caucasians.

The effect of RHIZOMA COPTIDIS and COPTIS CHINENSIS aqueous extract on radiation-induced skin injury in a rat model.

BACKGROUND: Radiation-induced skin injury is a common complication of radiotherapy. The RHIZOMA COPTIDIS and COPTIS CHINENSIS aqueous extract (RCE) can ameliorate radiation-induced skin injury in our clinical observation. But, the protective mechanism of RHIZOMA COPTIDIS and COPTIS CHINENSIS in radiation-induced skin injury remains unclear. METHODS: In this experiment, we developed a radiation-induced skin injury rat model to study the mechanism. The animals were randomly divided into control group, treatment group, radiation group, and treatment and radiation group. 5 rats in each group were separately executed on 2 d and 49 d post-radiation. The semi-quantitative skin injury score was used to measure skin reactions by unblinded observers, and hematoxylin and eosin staining was used to evaluate the damage areas by irradiation. The MDA content, SOD activity of skin and serum were measured to detect the oxidative stress. RESULTS: Acute skin reactions were caused by a single dose of 45 Gy of ß-ray irradiation, and the skin injury could be found in all rats receiving irradiation based on the observation of HE staining of skin at different time-points, while RCE could significantly ameliorate those changes. The MDA content in serum and skin of control rats was 4.13±0.12 mmol/ml and 4.95±0.35 mmol/mgprot on 2 d post-radiation. The rats receiving radiation showed an increased content of MDA (5.54±0.21 mmol/ml and 7.10±0.32 mmol/mgprot), while it was 4.57±0.21 mmol/ml and 5.95±0.24 mmol/mgprot after treated with RCE (p<0.05). Similar changes of the MDA content could be seen on 49 d post-radiation. However, the SOD activity of rats receiving radiation decreased compared with control group on both time-points, which was inhibited by RCE (p<0.05). Meanwhile, no valuable changes could be found between control group and treatment group on 2 d and 49 d. CONCLUSIONS: Our study provides evidences for the radioprotective role of RCE against radiation-induced skin damage in rats by modulating oxidative stress in skin, which may be a useful therapy for radiation-induced skin injury.

Up-regulation of hypoxia inducible factor-1α by cobalt chloride correlates with proliferation and apoptosis in PC-2 cells.

BACKGROUND: The exact mechanism of the effects of hypoxia on the proliferation and apoptosis in carcinoma cells is still conflicting. This study investigated the variation of hypoxia-inducible factor-1α(HIF-1α) expression and the apoptosis effect of hypoxia stimulated by cobalt chloride (CoCl(2)) in pancreatic cancer PC-2 cells. METHODS: PC-2 cells were cultured with different concentration (50-200 µmol/L) of CoCl(2) after 24-120 hours to simulate hypoxia in vitro. The proliferation of PC-2 cells was examined by MTT assay. The cellular morphology of PC-2 cells were observed by light inverted microscope and transmission electron microscope(EM). The expression of HIF-1α on mRNA and protein level was measured by semi-quantitative RT-PCR and Western blot analysis. Apoptosis of PC-2 cells were demonstrated by flow cytometry with Annexin V-FITC/PI double staining. RESULTS: MTT assay showed that the proliferation of PC-2 cells were stimulated in the first 72 h, while after treated over 72 h, a dose- dependent inhibition of cell growth could be observed. By using transmission electron microscope, swollen chondrosomes, accumulated chromatin under the nuclear membrane and apoptosis bodies were observed. Flow cytometer(FCM) analysis showed the apoptosis rate was correlated with the dosage of CoCl(2). RT-PCR and Western blot analysis indicated that hypoxia could up-regulate the expression of HIF-1α on both mRNA and protein levels. CONCLUSION: Hypoxic microenvironment stimulated by CoCl(2) could effectively induce apoptosis and influence cell proliferation in PC-2 cells, the mechanism could be related to up-expression of HIF-1α.

Prevalence and related factors of urinary incontinence among Hebei women of China.

BACKGROUND/AIMS: The aim of this study was to assess the prevalence and related factors of different types of urinary incontinence (UI) among Hebei women in China. METHODS: A total of 2,500 women aged 20 years or more were sampled and interviewed face-to-face by well-trained interviewers. RESULTS: Among these women, 35.2% (862/2,448) had UI. The prevalence of stress, urge, and mixed UI was 26.4% (647/2,448), 1.9% (47/2,448), and 6.9% (168/2,448), respectively. In multivariable logistic regression, age, constipation, pelvic organ prolapse, number of abortions, and cesarean sections were associated with both stress and mixed UI; body mass index, dysmenorrhea, vaginitis and cervicitis, fetal weight, and dystocia were associated with stress UI only; age of menarche and dystocia were associated with urge UI only, and living in a city or countryside, a history of pelvic operation, urinary infection, diseases of the respiratory system, heart disease, and alcohol consumption with mixed UI. CONCLUSIONS: UI is a highly prevalent condition among women in Hebei Province, PR China. Stress, urge, and mixed UI not only have some related factors in common but also have some different ones. Economic condition and a lack of UI-related knowledge are factors keeping patients from seeing a doctor.

[Inhibitory effects of Scutellaria barbate extracts on diethylnitrosamine-induced hepatocarcinoma in rats].

OBJECTIVE: To investigate the inhibitory effects of Scutellaria barbate extracts on diethylnitrosamine-induced hepatocarcinoma in rats. METHODS: Hepatocarcinoma model rats were induced by diethylnitrosamine (DEN). Sixty SD male rats were randomly divided into 4 groups: normal control group, hepatocarcinoma model group, ESB of high dose group and ESB of low dose group. All rats were killed in the 18th week, the levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bilirubin (TBIL), alkaline phosphatase (ALP), gamma-glutamyltransferase (gamma-GT) and alpha-L-fucosidase (AFU) in serum were measured by biochemical examinations; Hematoxy and eosin (HE) methods were used to examine the changes of liver pathology. RESULTS: The levels of ALT, AST, TBIL, ALP, gamma-GT, AFU in hepatocarcinoma model group and ESB groups were higher than that of control group (P < 0.05). ESB could relieve hepatic injures. The levels of liver function indexes in ESB groups were lower than that of model group. Histological examination demonstrated that the number of liver cancer nodus in ESB groups were lower than that of model group. Furthermore, ESB could attenuate the grade of cancer cell differentiation. CONCLUSION: ESB could inhibit experimental hepatocarcinoma and relieve hepatic injures in rats.

Matrine induces apoptosis in gastric carcinoma cells via alteration of Fas/FasL and activation of caspase-3.

AIM OF THE STUDY: Matrine, an alkaloid purified from the chinese herb Sophora flavescens Ait, is well known to possess activities including anti-inflammation, anti-fibrotic and anticancer. In this study, the mechanism of matrine inducing the apoptosis of gastric carcinoma cells was investigated. MATERIALS AND METHODS: Proliferation of SGC-7901 cells was examined by MTT assay. Cellular morphology was observed under transmission electron microscope. Flow cytometry (FCM) was used to observe the apoptosis of SGC-7901 cells by staining with annexinV-FITC/PI. The expression levels of Fas/FasL in SGC-7901 cells were monitored by FCM analysis using an indirect immunofluorescence method. Activity of caspase-3 enzyme was measured by spectrofluorometry. RESULTS: MTT assay showed that matrine inhibited SGC-7901 cells proliferation in a dose-dependent and time-dependent manner. Apoptosis induction was demonstrated by morphological changes under electron microscope and FCM analysis. Fluorescence intensity levels of Fas and FasL were found to be equally up-regulated after matrine treatment, which were both correlated with apoptosis rate. The activity of caspase-3 enzyme increased in matrine groups, positively correlated with apoptosis rate. CONCLUSIONS: Matrine could inhibit cell proliferation and induce apoptosis of SGC-7901 cells in vitro. The apoptosis induction appears to proceed by up-regulating Fas/FasL expression and activating caspase-3 enzyme.

Stealth tanshinone IIA-loaded solid lipid nanoparticles: effects of poloxamer 188 coating on in vitro phagocytosis and in vivo pharmacokinetics in rats.

Stealth tanshinone IIA-loaded solid lipid nanoparticles (TA-SSLNs) have been prepared and the influence of poloxamer 188 coating on in vitro phagocytosis and in vivo pharmacokinetics in rats were evaluated. TA-SSLNs have been prepared by a nanoprecipitation/solvent diffusion method. Poloxamer 188 was used as a stealth agent. The physicochemical parameters of TA-SSLNs were characterized in terms of particle size, zeta potential, transmission electron microscopy and stability. In vitro, phagocytosis was investigated by incubating TA-SSLNs and non-stealth tanshinone IIA-loaded solid lipid nanoparticles (TA-NSLNs) with murine macrophages. In vivo, pharmacokinetics of TA-SSLNs and TA-NSLNs after a single dose intravenous injection to rat has been studied. The control was tanshinone IIA solution (TA-SOL). The results showed that TA-SSLNs had an average diameter of (91.3 +/- 3.4) nm, zeta potential of (-19.7 +/- 1.6) mV, drug loading of (4.7 +/- 0.5) % and entrapment efficiency of (92.5 +/- 2.1) %. Phagocytosis studies showed significant differences between TA-SSLNs and TA-NSLNs and demonstrated that the poloxamer 188 coating could decrease the macrophage uptake. In vivo experiments showed that the plasma concentration data of TA-SSLNs, TA-NSLNs and TA-SOL were all fitted to a two-compartment model. Areas under curve (AUCs) of TA-NSLNs and TA-SSLNs were 1.28 and 3.70 times than that of TA-SOL, respectively. TA-SSLNs had generated a long circulating time in blood with a mean residence time (MRT) of 5.286 h, compared to 3.051 h of TA-NSLNs and 0.820 h of TA-SOL. Poloxamer 188 modification on solid lipid nanoparticles (SLNs) reduced opsonization by serum proteins and the macrophage uptake. AUC of tanshinone IIA increased as a function of SLNs. In addition, TA-SSLNs exhibited much longer circulation lifetimes for tanshinone IIA than TA-NSLNs. The pharmacokinetic behavior of the incorporated drug can be modified by changing the surface characteristics of SLNs with the use of poloxamer 188.

Scutellaria barbate extract induces apoptosis of hepatoma H22 cells via the mitochondrial pathway involving caspase-3.

AIM: To study the growth inhibitory and apoptotic effects of Scutellaria barbata D.Don (S. barbata) and to determine the underlying mechanism of its antitumor activity in mouse liver cancer cell line H22. METHODS: Proliferation of H22 cells was examined by MTT assay. Cellular morphology of PC-2 cells was observed under fluorescence microscope and transmission electron microscope (EM). Mitochondrial transmembrane potential was determined under laser scanning confocal microscope (LSCM) with rhodamine 123 staining. Flow cytometry was performed to analyze the cell cycle of H22 cells with propidium iodide staining. Protein level of cytochrome C and caspase-3 was measured by semi-quantitive RT-PCR and Western blot analysis. Activity of caspase-3 enzyme was measured by spectrofluorometry. RESULTS: MTT assay showed that extracts from S. barbata (ESB) could inhibit the proliferation of H22 cells in a time-dependent manner. Among the various phases of cell cycle, the percentage of cells in S phase was significantly decreased, while the percentage of cells in G(1) phase was increased. Flow cytometry assay also showed that ESB had a positive effect on apoptosis. Typical apoptotic morphologies such as condensation and fragmentation of nuclei and blebbing membrane of apoptotic cells could be observed under transmission electron microscope and fluorescence microscope. To further investige the molecular mechanism behind ESB-induced apoptosis, ESB-treated cells rapidly lost their mitochondrial transmembrane potential, released mitochondrial cytochrome C into cytosol, and induced caspase-3 activity in a dose-dependent manner. CONCLUSION: ESB can effectively inhibit the proliferation and induce apoptosis of H22 cells involving loss of mitochondrial transmembrane potential, release of cytochrome C, and activation of caspase-3.

[Antitumor and immune-modulating effects of Scutellaria barbata extract in mice bearing hepatocarcinoma H22 cells-derived tumor].

OBJECTIVE: To investigate the effects of Scutellaria barbata extract (ESB) in suppressing tumor growth and modulating the immune functions in mice bearing tumors derived from hepatocarcinoma H22 cells. METHODS: Fifty mice inoculated subcutaneously with H22 cells were equally divided into the model group, high-, moderate-, and low-dose ESB groups, and 5-Fu group, with corresponding treatments for 10 days. Another 10 mice with only saline injection served as the normal control group. The body weight, tumor mass, thymus index and spleen index of the mice were measured, and the lymphocyte proliferation activity, NK cell activity and interleukin-2 (IL-2) production by the splenocytes were detected. RESULTS: Moderate- and high-dose ESB significantly suppressed the tumor growth with tumor inhibition rate of 28.68% and 36.98%, respectively. ESB treatment at moderate and high doses significantly increased the thymus index and spleen index (P < 0.01), which were decreased significantly in 5-Fu group. The lymphocyte proliferation activity, NK cell activity and IL-2 production by the splenocytes were significantly lower in the model group than in the normal group (P < 0.05). Compared with the model group, ESB at the high dose obviously increased the three indexes above mentioned. The NK cell activity was also significantly improved in moderate-dose ESB group (P < 0.05). CONCLUSION: ESB can suppress the growth of H22 implant tumor and enhance the immune function of the tumor-bearing mice.

[Effects of activated PPARgamma on the expression of PTEN gene in pancreatic cancer cells].

AIM: To explore the relationship between the expression of PTEN gene and the expression of PPARgamma, and the human pancreatic cancer cells PANC-1 were cultured in vitro. METHODS: The effects of rosiglitazone and GW9662 on the expression of PTEN gene and PTEN protein in the human pancreatic cancer cells PANC-1 were detected by RT-PCR and immunohistochemistry respectively. In addition, the percentage of the expression of PTEN protein was analyzed by flow cytometry. RESULTS: The expression of PTEN gene and PTEN protein in human pancreatic cancer cells PANC-1 were all increased significantly after treated with rosiglitazone. While those were markedly reduced in GW9662 treated groups, and it has a dose-effect relationship between them. CONCLUSION: The expression of PTEN gene were paralleled with the expression of PPARgammain human pancreatic cancer cells PANC-1, which may be related to its inhibitory effects on pancreatic tumor cells.