[Optimization of medical educational objectives by improving summative assessment system].

Summative assessment plays a decisive role in the educational assessment system, which is a yardstick to measure the cultivating goal of higher education. The rapid progress of modern society has put forward higher standard for higher medical education. Traditional summative assessment system with single dimension that focuses on evaluating the student's learning outcome via a standardized examination cannot meet the higher requirements for undergraduate medical education. We have improved the summative assessment system by optimizing the assessment content, criteria and method, as well as teachers' assessment skills and students' evaluation. The reform greatly increases the teaching quality and learning effect in our university.

Reduction of PGRN increased fibrosis during skin wound healing in mice.

Progranulin (PGRN) is a multi-functional growth factor known to be involved in regulating of development, cell cycle progression, cell motility, tumorigenesis and angiogenesis. Research has revealed that PGRN is a crucial mediator of skin wound healing. Nonetheless, the role of PGRN in the fibrosis process of cutaneous wound healing has not been identified. In the present study, mice with excisional wounds were treated with si-m-PGRN or physiological saline. We observed the expression of PGRN in intact and post-injury skin by immunohistochemistry. Tissue sections of skin around the wound were performed by hematoxylin & eosin and masson's trichrome staining. After PGRN knockdown by siRNA, the expression of PGRN, collagen I (Col I), small mothers against decapentaplegic homolog 3 (Smad3), phosphorylated Smad3 (P-Smad3), transforming growth factor (TGF)-ß1 and TGF-ß receptor I (TßRI) were detected by real-time reverse transcription polymerase chain reaction (RT-qPCR) or Western blot. PGRN mRNA and protein expressions were increased after insult and remained above that of intact skin through day 20. Down-regulation of PGRN augmented fibrosis area, skin thickness and the expression of Col I. In addition, reduction of PGRN considerably increased the expression of TGF-ß1, TßRI, Smad3 and P-Smad3. These results indicate that PGRN knockdown enhances the fibrosis degree, probably via the TGF-ß/Smad signaling pathway.

Perturbation of epithelial apicobasal polarity by rhomboid family-1 gene overexpression.

The human rhomboid family (RHBDF)1 gene is highly expressed in breast cancer under clinical conditions but not in normal mammary gland tissues. Silencing the RHBDF1 gene in breast cancer xenograft tumors leads to inhibition of tumor growth. We show in this study that artificially raising RHBDF1 protein levels in the mammary epithelial cells MCF-10A results in severe perturbations of the ability of the cells to form lumen-containing acini, either in 3-dimensional cell cultures or implanted in mouse mammary fat pads. Knocking down RHBDF1 with short hairpin (sh)RNA leads to restoration of acinus formation. Consistently, RHBDF1 overexpression gives rise to disordered distribution of polarity markers GM130 and laminin-5, which otherwise are located in apical and basal positions, respectively, in the acini. Further investigations reveal that RHBDF1 directly binds to Par6a, a component of a protein complex consisting of partitioning-defective scaffold protein (Par)6, Par3, renin-angiotensin system-related C3 botulinum toxin substrate (Rac)1, and cell-division cycle (Cdc)42, which is structurally critical to the formation of apicobasal polarity. RHBDF1 binding to Par6a results in collapse of the protein complex and thus disruption of polarity formation. Since early stages of breast cancer are characterized by the loss of mammary gland epithelial cell polarity, our findings indicate that perturbations of apicobasal polarity by high levels of RHBDF1 is a significant attribute in the development of breast neoplasia.-Peng, X.-M., Gao, S., Deng, H.-T., Cai, H.-X., Zhou, Z., Xiang, R., Zhang, Q.-Z., Li, L.-Y. Perturbation of epithelial apicobasal polarity by rhomboid family-1 gene overexpression.

Continuous infusion of a large dose of CF (folinic acid) and 5-FU combined with CDDP in the treatment of advanced esophageal cancer.

5-fluorouracil (5-FU) and cisplatin (CDDP) are common chemotherapy drugs used in the treatment of patients with advanced esophageal cancer. We investigated the efficacy of adding a continuous infusion of a large dose of a common adjuvant, citrovorumfactor (CF), to the traditional 5-FU/wCDDP regimen. 50 patients with advanced esophageal cancer were treated with a continuous infusion of CF, 5-FU, and CDDP, and the short-term effects, adverse reactions, and survival periods after treatment were analyzed. Overall, the treatment was effective in 58% of patients, and the therapeutic effects of the first-line of chemotherapy were significantly better than the second-line (u = 4.121, p < 0.05). Patients experienced severe nausea and vomiting in 18.7% of the treatment cycles and experienced severe hair loss or leucopenia in 1.9% of the treatment cycles. The majority of the treatment cycles produced only mild side effects. The median survival period following chemotherapy treatment was 10.6 months (95% confidence interval was 8.146 ~ 13.054 months), with the median survival time of patients with a Karnofsky Performance Status (KPS) score ≥ 80 being significantly longer than that of patients with KPS scores < 80 (χ2 = 41.595, p < 0.05). The median survival time of patients with metastasis to the lymph nodes and surrounding tissue was significantly longer than that of patients with visceral metastasis (χ2 = 32.246, p < 0.05). Cox regression analysis showed that KPS scores before the treatment < 80 (relative risk (RR= = 1.635) and the incidence of visceral metastasis (RR = 1.875) were associated with survival time (p < 0.05). These results suggest that the continuous infusion of a large dose of CF, 5-FU, and CDDP as chemotherapy treatment of advanced esophageal cancer can produce promising short-term results and decrease adverse reactions.

TNFSF15 suppresses VEGF production in endothelial cells by stimulating miR-29b expression via activation of JNK-GATA3 signals.

Vascular endothelial cell growth factor (VEGF) plays a pivotal role in promoting neovascularization. VEGF gene expression in vascular endothelial cells in normal tissues is maintained at low levels but becomes highly up-regulated in a variety of disease settings including cancers. Tumor necrosis factor superfamily 15 (TNFSF15; VEGI; TL1A) is an anti-angiogenic cytokine prominently produced by endothelial cells in a normal vasculature. We report here that VEGF production in mouse endothelial cell line bEnd.3 can be inhibited by TNFSF15 via microRNA-29b (miR-29b) that targets the 3'-UTR of VEGF transcript. Blocking TNFSF15 activity by using either siRNA against the TNFSF15 receptor known as death domain-containing receptor-3 (DR3; TNFRSF25), or a neutralizing antibody 4-3H against TNFSF15, led to inhibition of miR-29b expression and reinvigoration of VEGF production. In addition, we found that TNFSF15 activated the JNK signaling pathway as well as the transcription factor GATA3, resulting in enhanced miR-29b production. Treatment of the cells either with SP600125, an inhibitor of JNK, or with JNK siRNA, led to eradication of TNFSF15-induced GATA3 expression. Moreover, GATA3 siRNA suppressed TNFSF15-induced miR-29b expression. These findings suggest that VEGF gene expression can be suppressed by TNFSF15-stimulated activation of the JNK-GATA3 signaling pathway which gives rise to up-regulation of miR-29b.

Gene expression profile of human esophageal squamous carcinoma cell line TE-1.

Esophageal squamous cell carcinoma (ESCC) is one of the most common and deadly causes of cancer worldwide. However, to date, the mechanisms underlying its pathogenesis remain unclear. The present study investigated the gene expression profile of human esophageal cancer cell line TE-1, a cell model for ESCC, to gain insight to the genetic regulation of this disease. Human esophageal cancer TE-1 cells and normal esophageal HET-1A cells were cultured for isolation of total RNA. Differential expression of RNA transcripts was assessed using the Agilent 4×44 K microarray, combined with real-time PCR (qRT-PCR) for validation. Classification and function of the differential genes were illustrated by bioinformatics processing including hierarchical clustering and gene ontology (GO) analysis. We identified 4,986 transcripts with differential expression (fold-change ≥1.5, P<0.05), including 2,368 up-regulated and 2,618 down-regulated transcripts. GO analysis showed that the dysregulated transcripts were associated with biological process, cellular component, and molecular function. After bioinformatic analysis of significantly regulated signaling pathways, we found these transcripts may target 35 gene pathways, including p53 signaling, glioma, ubiquitin-mediated proteolysis, insulin signaling, cell cycle, inositol phosphate metabolism, mTOR signaling, and MAPK signaling. The differentially expressed transcripts were screened between the esophageal cancer cell line TE-1 and normal esophageal cell line HET-1A, as well as their target gene pathways. Further data mining is related to prevention and treatment of esophageal cancer.

[Research of Identify Spatial Object Using Spectrum Analysis Technique].

The high precision scattering spectrum of spatial fragment with the minimum brightness of 4.2 and the resolution of 0.5 nm has been observed using spectrum detection technology on the ground. The obvious differences for different types of objects are obtained by the normalizing and discrete rate analysis of the spectral data. Each of normalized multi-frame scattering spectral line shape for rocket debris is identical. However, that is different for lapsed satellites. The discrete rate of the single frame spectrum of normalized space debris for rocket debris ranges from 0.978% to 3.067%, and the difference of oscillation and average value is small. The discrete rate for lapsed satellites ranges from 3.118 4% to 19.472 7%, and the difference of oscillation and average value relatively large. The reason is that the composition of rocket debris is single, while that of the lapsed satellites is complex. Therefore, the spectrum detection technology on the ground can be used to the classification of the spatial fragment.

The Dermatophagoides farinae group 22 allergen: cloning and expression in Escherichia coli.

BACKGROUND: Dermatophagoides farinae (Hughes) (Acari: Pyroglyphidae) and other domestic mites produce allergens that affect people worldwide. Here, the complementary DNA (cDNA) coding for group 22 allergen of D. farinae (Der f 22) from China was cloned, sequenced, and expressed successfully. METHODS: The cDNA encoding Der f 22 was synthesized by reverse transcription polymerase chain reaction (RT-PCR), then ligated to the pCold-TF for expression in Escherichia coli BL21 cells. The purified recombinant fusion protein was identified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), Western-blotting, and tandem matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF/TOF). RESULTS: The full-length cDNA comprised 468 nucleotides and was 99.57% (466/468) identical with the reference sequence (GenBank: DQ643992). After the plasmid pCold-TF-Der f 22 was transformed into E. coli BL21 and expressed with the induction of IPTG, SDS-PAGE showed a specific band for the recombinant fusion protein. The recombinant fusion protein, which was purified by chromatography, bound with a His-tagged antibody by Western blotting. MALDI-TOF/TOF mass spectrometry revealed that the structure of the recombinant protein was identical to the predicted Der f 22 structure. The hydrophilic protein contains a signal peptide of 20 amino acids, and the mature Der f 22 consists of 135 amino acid residues with a molecular weight of 14.7 kDa and theoretical isoelectric points (pI) of 6.38. Its secondary structure comprises an alpha helix (38.5%), beta-sheet (45.9%), random coils (11.85%), and beta-turns (11.1%). CONCLUSION: This work represents the first reported full-length sequence and successful cloning of Der f 22 from D. farinae in China; bioinformatics analysis can be used to further study the allergenicity and clinical utility of the recombinant Der f 22.

[Expression of caspase-3 and HAX-1 after cerebral contusion in rat].

OBJECTIVE: To observe the expression pattern of caspase-3 and HCLS1-associated protein X-1 (HAX-1) at different time after cerebral contusion in rat, and explore the new method for estimating the injury interval. METHODS: The cerebral contusion model was established using adult SD male rats. Then the rats were randomly allocated into 8 groups: 2 h, 6 h, 12 h, 1 d, 3 d, and 7 d after cerebral contusion, sham-operation and normal control. Expression of caspase-3 and HAX-1 protein after cerebral contusion in rat was detected by Western blotting. Laser scanning confocal microscope was used to observe the number of HAX-1 positive cells and TUNEL-stained cells after cerebral contusion. RESULTS: The expression of caspase-3 increased parallelly with the time after cerebral contusion and reached the peak value on 3 d. The expression of caspase-3 decreased gradually and still maintained a high level expression on 7 d (P < 0.05). The expression of HAX-1 positive cell went up after injury, and reached the peak value at 6 h (P < 0.05), then turned down gradually after 12 h and went out of detection after 3 d. The number of TUNEL-stained cells increased obviously at 2 h and reached the peak value on 3 d. The number of TUNEL-stained apoptotic cells decreased gradually and still maintained a high level expression on 7 d (P < 0.05). CONCLUSION: The expression of caspase-3 and HAX-1 after cerebral contusion has time sequential regularity, which may provide new evidence for forensic diagnosis of cerebral contusion interval.

[Raman spectra calculation and analysis of plasticizer dioctyl phthalate].

In recent years, with frequent domestic food safety incidents related to the plasticizing agent, the detection of plasticizers in food research becomes increasingly urgent. DEHP is one of the plasticizer. In the present paper, theoretical Raman spectrum and experimental Raman spectrum of DEHP were given. DEHP molecular structure was optimized by DFT(B3LYP) method. DEHP molecular Raman spectra and infrared spectra were calculated with. HF theory and DFT theory based on 3-2G level. The analytical reagent level DEHP Raman spectra was measured, and was compared with theoretical spectra, and good agreements were obtained between the theoretical and experimental results. Because of different calculation methods, we can see that both the wave number and relative intensity of peaks have small differences. DEHP structure parameters were also given in the paper including bond lengths and bond angles etc. Vibrational modes were assigned to all bands between 400 and 3 500 cm-1. Raman spectroscopy study of the commonly used plasticizer dioctyl phthalate was reported in this paper for the first time. This effort will contribute to the research and application of Raman spectroscopy in the field of food testing.

[Scattering properties of core-shell structure of mist wrapped dust particles].

The authors have investigated the optical properties of core-shell structure of mist wrapped dust particles based on the method of discrete dipole approximation (DDA). The influence on the thickness of the elliptical core-shell structure were calculated which the ratio of long axis and short axis is 2:1, and the change of scattering angle for scattering characteristics. The results shows that the thickness of outer layer increase from 1.2 to 4.8 µm with the scattering and extinction coefficient of double core-shell layers particles decrease from 3.4 and 3.43 to 2.543 and 2.545, when the size of inner core isn't change. And scattering relative strength also increased obviously. The thickness of inner core increase from 0.6 to 2.4 µm with the of scattering and extinction coefficient change from 2.59 and 2.88 to 2.6 and 2.76 when thickness of outer remain constant. Effect of the thickness of visible outer layer on the scattering characteristics of double core-shell layers particles is greater, because of the interaction between scattering light and outer materials. The scattering relative intensity decrease with wavelength increased, while increased with the scale of core-shell structure increase. The results make a promotion on the study of the transportation characteristics of laser and scattering characteristics when the atmospheric aerosol and water mist interact together.

[Optimization of melamine structure using density functional theory and vibrational spectra studies].

Melamine was used in foodstuff and feed industry as a feed additive occasionally. In the present work, melamine geometry structure was optimized by density functional theory (DFT) method. Raman and infrared spectra were calculated based on MP2/6-31G sets and DFT/DGTIVP sets, and then two theoretical Raman spectra were carefully compared with other experimental spectra. Good agreements were obtained between the theoretical and experimental results. Melamine structure parameters were given also in the paper including bond lengths and bond angles. Vibrational modes were assigned to all bands in the 550-4 000 cm(-1) range. This work will benefit the measurement research of the content of melamine in foods.

Reversion of multidrug resistance by SKI-II in SGC7901/DDP cells and exploration of underlying mechanisms.

In order to investigate whether SKI-II could reverse drug resistance and its possible mechanisms, we treated SGC7901/DDP cells with SKI-II or SKI-II in combination with DDP. Then cell growth, apoptosis, micro- morphological changes, and expression of SphK1, P-gp, NF-kB, Bcl-2 and Bax were assessed by MTT assay, flow cytometry, electron microscopy, immunocytochemistry and Western blot assay respectively. SGC7901/DDP cells were insensitive to cisplatin 2.5 mg/L, but when pretreated with SKI-II, their proliferation was inhibited by cisplatin 2.5mg/L significantly, the inhibition rate increasing with time and dose. The apoptosis rate was also significantly elevated. Expression of SphK1 and P-gp was decreased significantly, Pearson correlation analysis showing significant correlation between the two (r=0.595, P<0.01). Expression of NF-kB and Bcl-2 was decreased significantly, while that of Bax was increased, compared to the control group. There were significant correlations between SphK1 and NF-kB(r=0.723, P<0.01), and NF-kB and Bcl-2(r=0.768, P<0.01). All these data indicated that SKI-II could reverse drug resistance of SGC7901/DDP to cisplatin by down-regulating expression of P-gp and up-regulating apoptosis through down-regulation of SphK1. The increased apoptotic sensitivity of SGC7901/ DDP to cisplatin was due to the decreasing proportion of Bcl-2/Bax via down-regulating NF-kB.

Expression of paxillin and FAK mRNA and the related clinical significance in esophageal carcinoma.

The objective of the present study was to investigate the expression of paxillin and focal adhesion kinase (FAK) mRNA in esophageal carcinoma tissues, and their relationship with clinicopathological parameters, as well as to analyze the correlation of paxillin and FAK mRNA levels in esophageal carcinoma. By using reverse transcription polymerase chain reaction (RT-PCR), the mRNA expression levels of paxillin and FAK were detected in 121 samples of esophageal carcinoma, 43 samples of atypical hyperplasia and 56 samples of normal esophageal mucosa. The results showed that the positive rates of paxillin and FAK mRNA expression in esophageal carcinoma were 87.6 and 80.17%, respectively, which were significantly higher (P<0.05) than those in atypical hyperplasia (44.19 and 39.53%) and normal esophageal mucosa (5.36 and 12.5%). Notably, paxillin and FAK mRNA expression levels were significantly correlated with the differentiation degree and depth of invasion of esophageal carcinoma and with lymph node metastasis (P<0.05). In addition, paxillin and FAK mRNA expression levels in esophageal carcinoma were positively correlated (r=0.4804, P=0.000). In conclusion, the combined detection of paxillin and FAK mRNA expression is expected to provide a theoretical basis for the molecular diagnosis of esophageal carcinoma.

[Research on variable selection of wheat near-infrared spectroscopy based on latent projective graph].

To simplify the model and improve the precision of prediction model, latent projective graph (LPG) was used for variable selection. The original spectrum was processed by continuous wavelet transform (CWT), LPG was obtained by principal component analysis (PCA), and based on the assumption that collinear wavelengths might have the same contribution to the modeling, a few latent spectral variables were selected for establishing prediction model. The root mean square error of prediction (RMSEP) model was 0. 3454, better than other modeling methods. This work proved that variable selection with LPG could simplify the near-infrared spectral model effectively, and improve the precision of prediction model.

[Study on inversion of temperature distribution based on principal components analysis].

Multispectral radiation thermometry (MRT) is one of the methods for non-contact temperature measurement. The present MRT could invert only one approximate temperature value, and the actual temperature distribution could not be given. In the present article principal component analysis (PCA) was applied to solve the problem based on Planck' s laws. For example, in the laser damage target experiments, input laser pulse energy is 34.2 J, the inversion temperature value is 2 700 K from the thermal radiation spectrum. The fitting relative deviation is 0.5%, and when the temperature distribution is from 2 600 to 2 800 K, the fitting relative deviation is reduced to 0.13%. Temperature distribution inversion was shown based on PCA for the first time, and the measurement accuracy of non-contact temperature was improved.

[Raman scattering calculations studies of malachite green isothiocyanate].

Malachite green isothiocyanate (MGITC) is a Raman probe molecule that was applied to cells detection, tissue composition detection and cells stain imaging. In the present work, MGITC molecular structure was optimized by density functional theory(DFT) calculation. MGITC molecular Raman spectra and infrared spectra were calculated with Hartree-Fork theory and MP2 theory based on STO-3G level, then two theoretical Raman spectra were carefully compared with experimental spectra, and good agreements were obtained between the theoretical and experimental results. MGITC structure parameters were given also in the paper including bond lengths and bond angles etc. Vibrational modes were assigned to all bands in the range between 550 and 4 200 cm(-1). This work will facilitate the application of MGITC Raman probe for biology.

Cloning, expression, and characterization of Der f 7, an allergen of Dermatophagoides farinae from China.

A full-length cDNA encoding house dust mite allergen Der f 7 from Dermatophagoides farina (Acari: Pyroglyphidae) from China was cloned, sequenced, and successfully expressed. A reference sequence (GenBank accession AY283292) was used to design polymerase chain reaction primers. Analysis revealed eight mismatched nucleotides in five Der f 7 cDNA clones, and the projected amino acid sequence contained six incompatible residues. These results suggest that the sequence of Der f 7 may be polymorphic. Further bioinformatic analysis revealed that the mature Der f 7 allergen had a molecular mass of approximately 21.88 kDa and a theoretical isoelectric point of 4.90. Der f 7 protein secondary structure was composed of a helix (56.63%), extended strand (5.10%), and random coil (38.27%). Group 7 allergens are present in Pyroglyphidae, Acaridae, and Glycyphagidae families, and homology analysis revealed a 86% similarity between Der f 7 and Der p 7. Furthermore, a phylogenetic tree constructed of group 7 allergens from different mite species revealed that Der f 7 and Der p 7 clustered with 100% bootstrap support. Bioinformatics-driven characterization of Der f 7 allergen as conducted in this study may contribute to diagnostic and therapeutic applications for dust mite allergies.

[Raman spectrum study of 3.3'-diethylthiatri carbocyanine iodide].

3.3'-Diethylthiatricarbocyanine iodide (DTTC) dye is an important infrared Raman probe molecule, and has received great attention in the past decades due to their potential applications in Raman imaging, single cell detection, and tumor marker. In the present work, ordinary Raman, surface enhanced Raman scattering (SERS), and theoretical Raman spectra were given to estimate the Raman spectrum of DTTC suspension. More specifically, the original gold nanospheres (60-nm diameter) and gold nanorods (NRs) were encoded with DTTC and stabilized with a layer of thiol-polyethylene glycol (PEG) as Raman reporter, and SERS data were obtained from the samples. Density functional theory (DFT) calculation was applied to calculate the optimized Raman spectra of DTTC water solvent on a B3LYP/6-31G level. Subsequently, the obtained experimental spectra from the DTTC were carefully compared with the theoretically calculated spectra. From the spectra comparation, good agreements were obtained between the theoretical and experimental results. This work will facilitate the development of ultrasensitive SERS probes for advanced biomedical applications.

Cloning, sequence analysis and expression in E. coli of the group 3 allergen of Dermatophagoides farinae.

BACKGROUND: The dust mites, which are mostly represented by Dermatophagoides spp. (Acari: Pyroglyphidae), are the major sources of indoor allergens. Identification and characterization of these mite allergen molecules are an important step in the development of new effective diagnostic procedures and possible therapeutic strategies for allergic disorders associated with dust mites. METHODS: Total RNA was extracted from Dermatophagoides farinae. The gene coding for Der f 3 was amplified by RT-PCR with the primers designed based on previous sequence published in GenBank. The target gene was cloned intermediately into pMD19-T plasmid and finally into plasmid pET28a (+), expressed in E. coli BL21 at the aid of the inducer isopropyl-D-thiogalactopyranoside (IPTG). The physicochemical properties, spatial structure of the allergen were analyzed with bioinformatics software. RESULTS: The cDNA coding for group 3 allergen of Dermatophagoides farinae from China was cloned and expressed successfully. Sequencing analysis showed that there were nineteen mismatched nucleotides in five Der f 3 cDNA clones in comparison with the reference (GenBank Accession No. AY283291), which resulted in deduced amino acid sequence incompatibility in eleven residues. Bioinformatics analysis revealed that the Der f 3 pro-protein was an extracellular hydrophobic protein, consisting of 259 amino acids with a 16 amino acid signal peptide. The protein was deduced to have three chymotrypsin active sites (53-68 AA, 108-122 AA and 205-217 AA), one N-glycosylation site, one cAMP- and cGMP-dependent protein kinase phosphorylation site, four protein kinase C phosphorylation sites, two casein kinase II phosphorylation sites, and five N-myristoylation sites. CONCLUSIONS: Der f 3 is an extracellular hydrophobic protein which possesses multiple activation and phosphorylation sites. Polymorphism may exist in the Der f 3 gene but this needs to be further confirmed in the future.