[Efficacy of volume-targeted ventilation for the treatment of neonatal respiratory distress syndrome]

OBJECTIVE

To investigate the efficacy of volume-targeted ventilation (VTV) for the treatment of neonatal respiratory distress syndrome (NRDS).

METHODS

Fifty-two neonates with NRDS between August 2013 and August 2015 were randomly divided into two groups: VTV and pressure-controlled ventilation (PCV) (n=26 each ). A/C+Vc+ ventilation model was applied in the VTV group, and A/C+PCV ventilation model was applied in the PCV group. Arterial blood gas analysis was performed at 6, 24, and 48 hours after ventilation. The following parameters were observed: time of invasive ventilation, duration of oxygen therapy, mortality, and the incidence rates of hypocapnia, pneumothorax, ventilator-associated pneumonia (VAP), grade III-IV periventricular-intraventricular hemorrhage (PVH-IVH), periventricular leukomalacia (PVL), bronchopulmonary dysplasia (BPD), and retinopathy of prematurity (ROP).

RESULTS

Compared with the PCV group, the VTV group had a significantly shorter time of invasive ventilation (P<0.05) and significantly lower incidence rates of hypocapnia, VAP, and PVL (P<0.05); however, there were no significant differences in the duration of oxygen therapy, mortality, and incidence rates of pneumothorax, grade III-IV PVH-IVH, BPD, and ROP.

CONCLUSIONS

VTV has a better efficacy than PCV in the treatment of NRDS, and is worthy of clinical promotion and application.

Ultrasound Findings of Intraductal Papillary Neoplasm in Bile Duct and the Added Value of Contrast-Enhanced Ultrasound

PURPOSE

To investigate the imaging features of intraductal papillary neoplasm in bile duct (IPNB) on baseline ultrasound and contrast-enhanced ultrasound (CEUS).

MATERIALS AND METHODS

The imaging features on baseline ultrasound and CEUS in 16 pathologically proven IPNB lesions in 15 patients were retrospectively analyzed. Real-time contrast specific modes and contrast agent of SonoVue were used for CEUS.

RESULTS

Bile duct dilation was present in all patients. The mean lengths for the intraductal papillary adenomas and adenocarcinomas were 2.5 ± 1.1 (range, 1.2 - 4.2 cm) and 5.6 ± 2.0 cm (range, 3.3 - 9.8 cm) (P = 0.004). Three imaging types of IPNB on ultrasound were depicted: bile duct dilation with intraductal mass (n = 8), bile duct dilation without intraductal mass (n = 3), and cystic-solid mixed type (n = 5). On CEUS, solid components of 13 lesions appeared hyper- (n = 12) or iso-enhancement (n = 1) in the arterial phase whereas all showed hypo-enhancement in the portal and late phases. For 3 lesions of bile duct dilation without intraductal mass, CEUS showed non-enhancement during all phases. Pre-surgical CEUS and conventional ultrasound made correct diagnoses in 12 (75.0 %) and 5(31.3 %) of 16 IPNBs respectively (P = 0.04). For CECT, correct diagnosis was also achieved in 12 (75.0 %) of 16 lesions (P = 1.00, in comparison with CEUS).

CONCLUSIONS

IPNB should be taken into consideration when intraductal mass or cystic-solid mass with bile duct dilation, or remarkable bile duct dilation without intraductal mass, are found on US. Intraductal mass length > 3.0 cm is more commonly found in malignant IPNB. CEUS might facilitate the diagnosis of IPNB by easily excluding the possibility of commonly found sludge, nonshadowing stones, or blood clots.

Adjacent Fe-Vacancy Interactions as the Origin of Room Temperature Ferromagnetism in (In(1-x)Fe(x))2O3

Dilute magnetic semiconductors (DMSs) show great promise for applications in spin-based electronics, but in most cases continue to elude explanations of their magnetic behavior. Here, we combine quantitative x-ray spectroscopy and Anderson impurity model calculations to study ferromagnetic Fe-substituted In2O3 films, and we identify a subset of Fe atoms adjacent to oxygen vacancies in the crystal lattice which are responsible for the observed room temperature ferromagnetism. Using resonant inelastic x-ray scattering, we map out the near gap electronic structure and provide further support for this conclusion. Serving as a concrete verification of recent theoretical results and indirect experimental evidence, these results solidify the role of impurity-vacancy coupling in oxide-based DMSs.

Secondary thermophilic microaerobic treatment in the anaerobic digestion of corn straw

Thermophilic microaerobic pretreatment (TMP) has been proved to be an alternative pretreatment method during anaerobic digestion (AD) of corn straw. In this study, in order to improve the fermentation efficiency during late AD stage, improve the methane yield and volatile solid (VS) removal efficiency, a secondary thermophilic microaerobic treatment (STMT) was applied in the late AD stage of corn straw. Results showed STMT obviously improved the fermentation efficiency, methane yield and VS removal efficiency. The maximum methane yield and maximum VS removal efficiency were simultaneously obtained when the oxygen loads during STMT was 10 ml/g VS (VS of residual substrate). The maximum methane yield was 380.6 ml/g VS(substrate), which was 28.45% and 10.61% higher than those of untreated and once thermophilic microaerobic pretreated samples, respectively. The maximum VS removal efficiency was 81.85%, which was 29.43% and 17.23% higher than those of untreated and once thermophilic microaerobic pretreated samples, respectively.

Snail interacts with Id2 in the regulation of TNF-α-induced cancer cell invasion and migration in OSCC

The inflammatory tumor microenvironment has been identified to play a pivotal role in tumor development and metastasis. Tumor necrosis factor-α (TNF-α) is one of the key cytokines that regulate the inflammatory processes in tumor promotion. In the current study, we treated three oral squamous cell carcinoma (OSCC) cell lines with TNF-α to study its role in inflammation-induced tumor progression. Here we show that TNF-α induces stabilization of the transcriptional repressor Snail and activates NF-κB pathway in the three OSCC cell lines. These activities resulted in the increased motility and invasiveness of three OSCC cell lines. In addition, upon dealing with TNF-α for the indicated time, three OSCC cell lines underwent epithelial-to-mesenchymal transition (EMT), in which they presented a fibroblast-like phenotype and had a decreased expression of epithelial marker (E-cadherin) and an increased expression of mesenchymal marker (vimentin). We further demonstrated that TNF-α can up-regulate the expression of Id2 while inducing an EMT in oral cancer cells. Finally, we showed that Id2 interacted with Snail which may constrain Snail-dependent suppression of E-cadherin. In conclusion, our study indicates that TNF-α induces Snail stabilization is dependent on the activation of NF-κB pathway and results in increasing cell invasion and migration in OSCC cells. Id2 may contribute to regulate the function of Snail during TNF-α-mediated EMT in OSCC. These findings have significant implications for inflammation-induced tumor promotion in OSCC.

Role of miR-100 in the radioresistance of colorectal cancer cells

The prognosis of radioresistant colorectal cancer (CRC) is generally poor. Abnormal expression of microRNAs (miRNAs) is involved in the radiosensitivity of various tumor cells as these RNAs regulate biological signaling pathways. However, radioresistance-associated miRNAs in CRC have not yet been identified. In this study, we filtered out HCT116 and CCL-244 from seven CRC cell lines that showed the highest difference in radiosensitivity in a clonogenic assay. MiRNA sequencing identified 33 differentially expressed miRNAs (13 up-regulated and 20 down-regulated) in CCL-244 and 37 in HCT116 (20 up-regulated and 17 down-regulated) cells. MiR-100 was significantly down-regulated in CCL-244 cells after X-ray irradiation but not in HCT116 cells. Quantitative real-time PCR showed that the expression of miR-100 in CRC tissues was significantly lower than that in normal tissues. Thus, miR-100 seems to be involved in the radioresistance of CCL-244 cells. MiR-100 up-regulation sensitized CCL-244 cells to X-ray irradiation, which probably led to apoptosis and DNA double-strand breaks in these. In conclusion, to our knowledge, this is the first study to show that miR-100 may play an important role in regulating the radiosensitivity of CRC, and it may act as a new clinical target for CRC radiotherapy.

Role of non-coding RNAs in pancreatic cancer: The bane of the microworld

Our understanding of the mechanisms underlying the development of pancreatic cancer has been greatly advanced. However, the molecular events involved in the initiation and development of pancreatic cancer remain inscrutable. None of the present medical technologies have been proven to be effective in significantly improving early detection or reducing the mortality/morbidity of this disease. Thus, a better understanding of the molecular basis of pancreatic cancer is required for the identification of more effective diagnostic markers and therapeutic targets. Non-coding RNAs (ncRNAs), generally including microRNAs and long non-coding RNAs, have recently been found to be deregulated in many human cancers, which provides new opportunities for identifying both functional drivers and specific biomarkers of pancreatic cancer. In this article, we review the existing literature in the field documenting the significance of aberrantly expressed and functional ncRNAs in human pancreatic cancer, and discuss how oncogenic ncRNAs may be involved in the genetic and epigenetic networks regulating functional pathways that are deregulated in this malignancy, particularly of the ncRNAs’ role in drug resistance and epithelial-mesenchymal transition biological phenotype, with the aim of analyzing the feasibility of clinical application of ncRNAs in the diagnosis and treatment of pancreatic cancer.

[Pathological changes of after trans-portal vein chemoembolization Echinococcus multilocularis in the liver of infected rats]

OBJECTIVE

To observe the morphological change in the pathological process of Echinococcus multilocularis in liver of infected rats after treatment with liposome entrapped albendazole and iodized oil suspension through portal vein, and investigate its efficacy against hepatic alveolar echinococcosis.

METHODS

One Echinococcus multilocularis-infected rat served as control. Another 19 infected rats were infused with 0.2ml liposome entrapped albendazole and iodized oil suspension through portal vein. At 4, 7 and 10 d after treatment, the rats were sacrificed for further observation. The E. multilocularis metacestodes were collected, and the pathological change of alveolar hydatid was observed with hematoxylin-eosin staining and toluidine blue staining.

RESULTS

In four days post treatment, E. multilocularis metacestodes were normal On the 7th day and 10th day post treatment, the major pathological change was degeneration and necrosis, respectively. A great quantity of liposomes and iodized oil deposited in the metacestodes, and caused breakdown of E. multilocularis tissue, collapse of cysts, cataplasia of germinal layer and laminated layer.

CONCLUSION

Interventional therapy trans-hepatic vein may be an effective way to treat hepatic alveolar echinococcosis.

TRPM7 channels regulate proliferation and adipogenesis in 3T3-L1 preadipocytes

Transient receptor potential melastatin-7 (TRPM7) channels are involved in many cellular physiological and pathological processes. The present study was designed to investigate the expression of TRPM7 channels and the potential role in regulating cell proliferation and adipogenesis in 3T3-L1 preadipocytes with approaches of whole-cell patch voltage-clamp, molecular biology, cell proliferation, adipogenesis, etc. We found that a TRPM7-like current was recorded with Mg(2+) -free pipette solution in 3T3-L1 preadipocytes, and the current was inhibited by intercellular free Mg(2+) . The TRPM7-like current was potentiated by acidic pH and inhibited by 2-aminoethoxydiphenyl borate (2-APB). RT-PCR, Western blot and immunocytochemistry revealed that gene and protein of TRPM7 channels were abundant in 3T3-L1 preadipocytes. Blockade of TRPM7 channels with 2-APB inhibited cell proliferation in 3T3-L1 cells. In addition, knockdown of TRPM7 with specific siRNA inhibited both proliferation and adipogenesis. The present study demonstrates for the first time that TRPM7 channels regulate cell cycle and adipogenesis of 3T3-L1 preadipocytes.

DPMA, a deoxypodophyllotoxin derivative, induces apoptosis and anti-angiogenesis in non-small cell lung cancer A549 cells

We found that the deoxypodophyllotoxin derivative, 2,6-dimethoxy-4-(6-oxo-(5R,5aR,6,8,8aR,9-hexahydrofuro[3',4':6,7]naphtho[2,3-d][1,3]dioxol-5-yl)phenyl ((R)-1-amino-4-(methylthio)-1-oxobutan-2-yl)carbamate (DPMA), exhibited superior cytotoxicity compared with etoposide. In this study, we investigated the mechanism of action of DPMA. DPMA exhibited anti-proliferative activity and induced apoptosis in A549 cells in a dose- and time-dependant manner. DPMA inhibited microtubule formation and induced expression of Bax, cleaved caspase-3, p53 and ROS, and inhibited Bcl-2 expression. DPMA also affected cyclinB1, cdc2 and p-cdc2 expression, inducing cell cycle arrest. DPMA also inhibited tube formation of VEGF-induced human umbilical vein endothelial cells. These studies demonstrate that DPMA inhibits p53/cdc2/Bax signaling, thereby inhibiting cell growth/angiogenesis and inducing apoptosis.

Molecular characterization of bacterial and archaeal communities in a full-scale anaerobic reactor treating corn straw

A 16S rRNA gene-based method was used to characterize the structure of bacterial and archaeal communities in a full-scale, anaerobic reactor treating corn straw. Degradability experiment indicated biogas slurry had high microbial activity, the TS removal rate was 53% and the specific methanogenic activity was 86 mL CH4 g VSS(-1) d(-1). During anaerobic degradation of corn straw, volatile acids and aromatic compounds (p-cresol, phenylpropionate, phenol and benzoate) were detected as transient intermediates. Phylogenetic analysis revealed bacterial community exhibited high diversity, 69 bacterial phylotypes in 13 phyla were identified. Firmicutes (48.3%), Chloroflexi (20.1%), Actinobacteria (9.1%), Bacteroidetes (7.7%), and Proteobacteria (7.2%) represented the most abundant bacterial phyla. Hydrolytic and fermentative bacteria were major bacterial populations. Moreover, a relatively high proportion of syntrophic propionate and aromatic compounds degrading bacteria were detected. In the archaeal clone library, 11 archaeal phylotypes affiliated with two phyla of Crenarchaeota (10%) and Euryarchaeota (90%) were identified.

Synthesis and cytotoxic activity on human cancer cells of carbamate derivatives of 4β-(1,2,3-triazol-1-yl)podophyllotoxin

Carbamate derivatives of 4β-(1,2,3-triazol-1-yl)podophyllotoxin were synthesized by means of click chemistry, and their cytotoxicities against human cancer cell lines HL-60, A-549, HeLa, and HCT-8 were evaluated. Some compounds were more potent than the anticancer drug etoposide. 4'-O-Demethyl-4β-[(4-hydroxymethyl)-1,2,3-triazol-1-yl]-4-deoxypodophyllotoxin cyclopentyl carbamate, the most potent compound, induced cell cycle arrest in the G2/M phase accompanied by apoptosis in A-549 cells. Furthermore, this compound inhibited the formation of microtubules in A-549 cells and caused the inhibition of DNA topoisomerase-II.

Membrane Type 1 Matrix Metalloproteinase induces an epithelial to mesenchymal transition and cancer stem cell-like properties in SCC9 cells

BACKGROUND

Tissue invasion and metastasis are acquired abilities of cancer and related to the death in oral squamous cell carcinoma (OSCC). Emerging observations indicate that the epithelial-to-mesenchymal transition (EMT) is associated with tumor progression and the generation of cells with cancer stem cells (CSCs) properties. Membrane Type 1 Matrix Metalloproteinase (MT1-MMP) is a cell surface proteinase, which is involved in degrading extracellular matrix components that can promote tumor invasion and cell migration.

METHODS

In the current study, we utilized SCC9 cells stably transfected with an empty vector (SCC9-N) or a vector encoding human MT1-MMP (SCC9-M) to study the role of MT1-MMP in EMT development.

RESULTS

Upon up-regulation of MT1-MMP, SCC9-M cells underwent EMT, in which they presented a fibroblast-like phenotype and had a decreased expression of epithelial markers (E-cadherin, cytokeratin18 and β-catenin) and an increased expression of mesenchymal markers (vimentin and fibronectin). We further demonstrated that MT1-MMP-induced morphologic changes increased the level of Twist and ZEB, and were dependent on repressing the transcription of E-cadherin. These activities resulted in low adhesive, high invasive abilities of the SCC9-M cells. Furthermore, MT1-MMP-induced transformed cells exhibited cancer stem cell (CSC)-like characteristics, such as low proliferation, self-renewal ability, resistance to chemotherapeutic drugs and apoptosis, and expression of CSCs surface markers.

CONCLUSIONS

In conclusion, our study indicates that overexpression of MT1-MMP induces EMT and results in the acquisition of CSC-like properties in SCC9 cells. Our growing understanding of the mechanism regulating EMT may provide new targets against invasion and metastasis in OSCC.

[Phylogenetic analysis of methanogenic corn stalk degrading microbial communities]

Methanogenic corn stalk degrading enrichment cultures were constructed using corn stalk as the sole carbon source and eight types of environmental samples as inocula. All the cultures could degrade corn stalk within 30-50 days and the total solids (TS) removal rates were in the range of 30%-40%. In six out of eight cultures, the cumulative methane yields per gram TS were 62.1-118.4 mL x g(-1), with acetate, propionate and butyrate as the major volatile fatty acids (100-500 mg x L(-1)), and the final pH were 6.5-6.7. In the other two cultures, the cumulative methane yields per gram TS were 8.5-9.7 mL xg(-1), while the concentrations of acetate were high (1200 mg x L(-1)), and the final pH were low (5.6-5.9). The bacterial and archaeal structures in eight enrichments were investigated with a 16S rRNA genes-based clone library method. Clones belonging to the bacterial phyla Firmicutes, Bacteroidetes, Synergistetes and Thermotogae were observed in abundance within the bacterial clone libraries, which accounted for 37.8%, 34.3%, 11.6% and 6.4% of the total number of bacterial clones, respectively. Within the domain Archaea, clones affiliated with the classes Methanomicrobia and Methanobacteria were found to be abundant in the archaeal clone libraries, which accounted for 61.1% and 38.9% of the total number of archaeal clones, respectively.

Determining the age of adult flesh flies, Boettcherisca peregrina, using pteridine fluorescence

To assess the potential application of pteridine fluorescence in determining the age of adult Boettcherisca peregrina (Diptera: Sarcophagidae) Robineau-Desvoidy and further for the postmortem interval, the age-dependent changes of pteridine fluorescence were investigated for the adults maintained at five constant temperatures. From the results, significant linear relationships were found between pteridine fluorescence and the age of the adults maintained at 16, 20, 24, 28 or 32 °C (P < 0.001, r(2) > 0.85). In addition, the relationships between the rate of pteridine accumulation and temperature were well described using linear equations for adult females and males. Then for each cohort of the flies at the ambient temperature, a calendar was constructed and used to determine the ages of females and males, respectively, in which was recorded in reverse time order the amount of pteridine accumulated per hour by the flies and their expected pteridine level when they emerged at the specified time. A significant linear relationship between estimated ages and chronological ages was observed for female or male adults, with the mean errors of the estimated ages of ±1.82 days for females and ±1.58 days for males. It is suggested that pteridine fluorescence analysis has a potential value in determining the age of adult B. peregrina.

Allitridi inhibits multiple cardiac potassium channels expressed in HEK 293 cells

Allitridi (diallyl trisulfide) is an active compound (volatile oil) from garlic. The previous studies reported that allitridi had anti-arrhythmic effect. The potential ionic mechanisms are, however, not understood. The present study was designed to determine the effects of allitridi on cardiac potassium channels expressed in HEK 293 cells using a whole-cell patch voltage-clamp technique and mutagenesis. It was found that allitridi inhibited hKv4.3 channels (IC₅₀ = 11.4 µM) by binding to the open channel, shifting availability potential to hyperpolarization, and accelerating closed-state inactivation of the channel. The hKv4.3 mutants T366A, T367A, V392A, and I395A showed a reduced response to allitridi with IC₅₀s of 35.5 µM, 44.7 µM, 23.7 µM, and 42.4 µM. In addition, allitridi decreased hKv1.5, hERG, hKCNQ1/hKCNE1 channels stably expressed in HEK 293 cells with IC₅₀s of 40.2 µM, 19.6 µM and 17.7 µM. However, it slightly inhibited hKir2.1 current (100 µM, inhibited by 9.8% at −120 mV). Our results demonstrate for the first time that allitridi preferably blocks hKv4.3 current by binding to the open channel at T366 and T367 of P-loop helix, and at V392 and I395 of S6 domain. It has a weak inhibition of hKv1.5, hERG, and hKCNQ1/hKCNE1 currents. These effects may account for its anti-arrhythmic effect observed in experimental animal models.

Plasma treatment of electrospun PCL random nanofiber meshes (NFMs) for biological property improvement

In this article, the plasma surface modification effects on the chemical, mechanical, and biological properties of electrospun poly (ε-caprolactone) (PCL) random nanofiber meshes (NFMs) were investigated by adjusting plasma chemistry, that is, using glow discharges of N(2) +H(2), NH(3) +O(2), and Ar+O(2) gas mixtures. The surface property changes of electrospun PCL NFMs after those plasma treatments were examined by water contact angle measurements and X-ray photoelectron spectroscopy. The experimental results showed that the plasma treatments introduced polar groups onto the surfaces and thus increased the surface hydrophilicity. From tensile test data, plasma treatment had limited effect on the mechanical properties of PCL random NFMs. The biological properties of the plasma-treated PCL NFMs were examined by cell proliferation assays using mouse osteoblast cells (MC3T3-E1). It was found that the plasma-treated PCL NFMs gave a higher proliferation rate and improved cell adhesion properties as compared with the untreated controls.

Transplantation of tissue-engineered human corneal epithelium in limbal stem cell deficiency rabbit models

AIM

To evaluate the biological functions of tissue-engineered human corneal epithelium (TE-HCEP) by corneal transplantation in limbal stem cell deficiency (LSCD) rabbit models.

METHODS

TE-HCEPs were reconstructed with DiI-labeled untransfected HCEP cells and denuded amniotic membrane (dAM) in air-liquid interface culture, and their morphology and structure were characterized by hematoxylin-eosin (HE) staining of paraffin-sections, immunohistochemistry and electron microscopy. LSCD models were established by mechanical and alcohol treatment of the left eyes of New Zealand white rabbits, and their eyes were transplanted with TE-HCEPs with dAM surface outside by lamellar keratoplasty (LKP). Corneal transparency, neovascularization, thickness, and epithelial integrality of both traumatic and post transplantation eyes were checked once a week by slit-lamp corneal microscopy, a corneal pachymeter, and periodic acid-Schiff (PAS) staining. At day 120 post surgery, the rabbits in each group were sacrificed and their corneas were examined by DiI label observation, HE staining, immunohistochemistry and electron microscopy.

RESULTS

After cultured for 5 days on dAM, HCEP cells, maintaining keratin 3 expression, reconstructed a 6-7 layer TE-HCEP with normal morphology and structure. The traumatic rabbit corneas, entirely opaque, conjunctivalized and with invaded blood vessels, were used as LSCD models for TE-HCEP transplantation. After transplantation, obvious edema was not found in TE-HCEP-transplanted corneas which became more and more transparent, the invaded blood vessels reduced gradually throughout the monitoring period. The corneas decreased to normal thickness on day 25, while those of dAM eyes were over 575µm in thickness during the monitoring period. A 4-5 layer of epithelium consisting of TE-HCEP originated cells attached tightly to the anterior surface of stroma was reconstructed 120 days after TE-HCEP transplantation, which was similar to the normal control eye in morphology and structure. In contrast, intense corneal edema, turbid, invaded blood vessels were found in dAM eyes, and no multilayer epithelium was found but only a few scattered conjunctiva-like cells appeared.

CONCLUSION

The TE-HCEP, with similar morphology and structure to those of innate HCEP, could reconstruct a multilayer corneal epithelium with normal functions in restoring corneal transparency and thickness of LSCD rabbits after transplantation. It may be a promising HCEP equivalent for clinical therapy of corneal epithelial disorders.

Effects of the natural flavone trimethylapigenin on cardiac potassium currents

The natural flavones and polymethylflavone have been reported to have cardiovascular protective effects. In the present study, we determined whether quecertin, apigenin and their methylated compounds (3,7,3',4'-tetramethylquecertin, 3,5,7,3',4'-pentamethylquecertin, 7,4'-dimethylapigenin, and 5,7,4'-trimethylapigenin) would block the atrial specific potassium channel hKv1.5 using a whole-cell patch voltage-clamp technique. We found that only trimethylapigenin showed a strong inhibitory effect on hKv1.5 channel current. This compound suppressed hKv1.5 current in HEK 293 cell line (IC₅₀=6.4 μM), and the ultra-rapid delayed rectify K⁺ current I(Kur) in human atrial myocytes (IC₅₀=8.0 μM) by binding to the open channels and showed a use- and frequency-dependent manner. In addition, trimethylapigenin decreased transient outward potassium current (I(to)) in human atrial myocytes, inhibited acetylcholine-activated K⁺ current (IC₅₀=6.8μM) in rat atrial myocytes. Interestingly, trimethylapigenin had a weak inhibition of hERG channel current. Our results indicate that trimethyapigenin significantly inhibits the atrial potassium currents hKv1.5/I(Kur) and I(KACh), which suggests that trimethylapigenin may be a potential candidate for anti-atrial fibrillation.

Snail overexpression induces an epithelial to mesenchymal transition and cancer stem cell-like properties in SCC9 cells

Local invasiveness and distant metastasis are critical factors that contribute to oral squamous cell carcinoma-related deaths. Increasing evidence has shown that the epithelial to mesenchymal transition (EMT) is involved in cancer progression and is associated with the 'stemness' of cancer cells. Snail is a transcriptional factor that can induce EMT and preserve stem-cell function, which may induce resistance to radio- and chemotherapies in the cells. In the present study, SCC9 cells were transfected with an empty vector or a vector encoding human Snail (SCC9-S). Overexpression of Snail induced SCC9 cells to undergo EMT, in which the cells presented a fibroblast-like appearance, downregulated the epithelial markers E-cadherin and β-catenin, upregulated the mesenchymal marker vimentin, and associated with highly invasive and metastatic properties. Furthermore, the induction of EMT promoted cancer stem cell (CSC)-like characteristics in the SCC9-S cells, such as low proliferation, self-renewal, and CSC-like markers expression. These results indicate that overexpression of Snail induces EMT and promotes CSC-like traits in the SCC9 cells. Further understanding the role of Snail in cancer progression may reveal new targets for the prevention or therapy of oral cancers.

Lgl1 activation of rab10 promotes axonal membrane trafficking underlying neuronal polarization

Directed membrane trafficking is believed to be crucial for axon development during neuronal morphogenesis. However, the underlying mechanisms are poorly understood. Here, we report a role of Lgl1, the mammalian homolog of Drosophila tumor suppressor Lethal giant larvae, in controlling membrane trafficking underlying axonal growth. We find that Lgl1 is associated with plasmalemmal precursor vesicles and enriched in developing axons. Lgl1 upregulation promoted axonal growth, whereas downregulation attenuated it as well as directional membrane insertion. Interestingly, Lgl1 interacted with and activated Rab10, a small GTPase that mediates membrane protein trafficking, by releasing GDP dissociation inhibitor (GDI) from Rab10. Furthermore, Rab10 lies downstream of Lgl1 in axon development and directional membrane insertion. Finally, both Lgl1 and Rab10 are required for neocortical neuronal polarization in vivo. Thus, the Lgl1 regulation of Rab10 stimulates the trafficking of membrane precursor vesicles, whose fusion with the plasmalemma is crucial for axonal growth.

Assessment of urinary N-acetyl-β-glucosaminidase as an early marker of contrast-induced nephropathy

Early detection and timely intervention are important for improving contrast-induced nephropathy (CIN) prognosis. Whether urinary N-acetyl-β-glucosaminidase (NAG) is a useful marker for early detection of CIN was investigated in 590 patients undergoing diagnostic coronary angiography (CA) and/or therapeutic percutaneous coronary intervention (PCI) for acute coronary syndromes or stable angina, and who received low-osmolality nonionic contrast agent. Urinary NAG, osmolality and serum creatinine were measured before and 1, 2 and 6 days after contrast agent exposure. CIN occurred in 33 patients; its incidence in high-risk patients (pre-existing renal dysfunction with/without diabetes mellitus) was significantly higher than in others. In patients with CIN, urinary NAG and serum creatinine levels on days 1 and 2 were significantly higher than at baseline and compared with patients without CIN; mean levels were gradually returning to baseline by day 6. Compared with serum creatinine, urinary NAG levels peaked earlier in CIN patients and increased much more. The results suggest that, following CA and/or PCI, CIN occurs to a certain degree and that NAG may be a useful early CIN marker as it is noninvasive, simple, inexpensive and sensitive.

Thymidine kinase 1 is a potential marker for prognosis and monitoring the response to treatment of patients with breast, lung, and esophageal cancer and non-Hodgkin's lymphoma

Thymidine kinase 1 (TK1) is converting thymidine to thymidine monophosphate, and is related to DNA replication and cell proliferation. The use of the TK1 protein levels as a proliferation marker in malignancies is here summarized. TK1 protein in serum (STK1p) and TK1 expression in tissues were determined by a chemoluminescent dot blot assay and by immunohistochemistry staining, respectively. The expression of TK1 in tumor tissues correlated to pathological stages and clinical grades of carcinomas (ca) of esophagus, lung and in premalignancy of breast ductal ca. STK1p could monitor the out-come of tumor therapy by being correlated to remission [breast ca, non-Hodgkin's lymphoma], relapse [breast ca] and to survival [non-Hodgkin's lymphoma] of patients. In a health screening study of 12,641 persons, STK1p seemed to predict the risk of development of neoplasia related diseases at early stage.

Extraction and mechanism investigation of trace roxithromycin in real water samples by use of ionic liquid-salt aqueous two-phase system

The ionic liquid, as a green solvent, has several advantages over the organic solvents in traditional liquid-liquid extraction. Aqueous two-phase system (ATPS) consisting of a hydrophilic ionic liquid (1-butyl-3-methylimidazolium tetrafluoraborate, [Bmim]BF(4)) and Na(2)CO(3), which is a novel, simple, non-toxic and effective sample pretreatment technique coupled with molecular fluorescence spectrophotometry, was developed for the simultaneous separation, enrichment and rapid analysis of roxithromycin. The extraction yield of roxithromycin in [Bmim]BF(4)-Na(2)CO(3) aqueous two-phase system is influenced by the types of salts, concentrations of Na(2)CO(3) and [Bmim]BF(4), as well as the extracting temperature. Under the optimum conditions, the average extraction efficiency is up to 90.7%. The mechanism of ionic liquid-salt ATPS formation was discussed by hydration theory, and the extraction mechanism of the [Bmim]BF(4)-salt ATPS was investigated by FT-IR spectroscopy and UV-vis spectroscopy. The results demonstrate that no chemical (bonding) interactions are observed between ionic liquid and roxithromycin, while the nature properties of the roxithromycin are not altered. This method was practical when applied to the analysis of roxithromycin in real water samples with the detection limit of 0.03 microg mL(-1), relative standard deviation (RSD) of 1.9% (n=13), and linear ranges of 1.00-20.00 microg mL(-1). The proposed extraction technique will be promising in the separation of other small biomolecules.

Allelochemicals and activities in a replanted Chinese fir (Cunninghamia lanceolata (Lamb.) Hook) tree ecosystem

Autotoxicity is a major reason for replant problems in managed tree ecosystems. Studies have related phenolics-based allelochemicals to autotoxicity. We selected a 20-year-old replanted Chinese fir [Cunninghamia lancealata (Lamb.) Hook] tree ecosystem to isolate, identify, determine the biological activity of, and quantify soil phytotoxins. Eight common phenolics (coumarin, vanillin, isovanillin, and p-hydroxybenzoic, vanillic, benzoic, cinnamic, and ferulic acids), friedelin, and a novel cyclic dipeptide (6-hydroxy-1,3-dimethyl-8-nonadecyl-[1,4]-diazocane-2,5-diketone) were obtained by using the bioassay-guided isolation technique from toxic soil of the replanted Chinese fir tree ecosystem. Chemical structures were determined by spectroscopic means, including 2D-NMR (COSY, HMQC, HMBC, and NOESY) experiments. High concentrations of soil phenolics and friedelin were observed in the natural evergreen broadleaf forest (CK) rather than in the Chinese fir tree ecosystem. The phenolics and friedelin were not phytotoxic to Chinese fir trees. However, the cyclic dipeptide inhibited Chinese fir growth at soil concentrations determined in the replanted Chinese fir tree ecosystem. There was a significantly higher soil concentration of cyclic dipeptide in the replanted Chinese fir tree ecosystem than in a fresh Chinese fir tree ecosystem. The results suggest that phenolics and friedelin are not key allelochemicals since they are weakly phytotoxic and are detected in low concentrations in the replanted Chinese fir tree ecosystem, while cyclic dipeptide is a highly active allelochemical with a phytotoxic effect that limits offspring growth in the replanted Chinese fir tree ecosystem. The discovery of cyclic dipeptide, as well as a further understanding of its potential action mechanism in the replanted Chinese fir tree ecosystem, may contribute to solving the replant problems in managed tree ecosystems.

Fate and impact on microorganisms of rice allelochemicals in paddy soil

Allelopathic rice can release allelochemicals from roots to inhibit neighboring plant species, but little is currently known about their fate and impact on microorganisms in paddy soil. This study showed that allelopathic rice PI312777 released much higher concentrations of allelochemical (5,7,4'-trihydroxy-3',5'-dimethoxyflavone) than non-allelopathic rice Liaojing-9 in field. When quantitative 5,7,4'-trihydroxy-3',5'-dimethoxyflavone was added into soil, flavone gave a short half-life of 18.27 +/- 2.32 h (r(2) = 0.94) and could easily be degraded into benzoic acid. Benzoic acid with a half-life of 29.99 +/- 2.19 h (r(2) = 0.96) was more resistant toward degradation in paddy soil. Furthermore, both the culturable microbial population and the entire microbial community structure of soil incubated with flavone and benzoic acid were evaluated using the soil dilution plate method and phospholipid fatty acid (PLFA) analysis, respectively. It appeared from the results that flavone could reduce microorganisms especially for fungi present in paddy soil, while benzoic acid could induce a higher response for soil microorganisms especially for bacteria. Consequently, flavone would be responsible for the dynamics of soil microorganisms during the early period, and any observed effect during the late period would be very likely due to its degradation product benzoic acid rather than flavone itself. These results suggested that allelopathic rice varieties could modify soil microorganisms to their advantage through the release of allelochemicals. The concentration and fate of discriminating 5,7,4'-trihydroxy-3',5'-dimethoxyflavone between allelopathic and non-alleloparhic varieties tested in rice soil would result in the different patterns of microbial population and community structure in paddy ecosystems.

Acacetin, a natural flavone, selectively inhibits human atrial repolarization potassium currents and prevents atrial fibrillation in dogs

BACKGROUND

The development of atrium-selective antiarrhythmic agents is a current strategy for inhibiting atrial fibrillation (AF). The present study investigated whether the natural flavone acacetin from the traditional Chinese medicine Xuelianhua would be an atrium-selective anti-AF agent.

METHODS AND RESULTS

The effects of acacetin on human atrial ultrarapid delayed rectifier K(+) current (I(Kur)) and other cardiac ionic currents were studied with a whole-cell patch technique. Acacetin suppressed I(Kur) and the transient outward K(+) current (IC(50) 3.2 and 9.2 mumol/L, respectively) and prolonged action potential duration in human atrial myocytes. The compound blocked the acetylcholine-activated K(+) current; however, it had no effect on the Na(+) current, L-type Ca(2+) current, or inward-rectifier K(+) current in guinea pig cardiac myocytes. Although acacetin caused a weak reduction in the hERG and hKCNQ1/hKCNE1 channels stably expressed in HEK 293 cells, it did not prolong the corrected QT interval in rabbit hearts. In anesthetized dogs, acacetin (5 mg/kg) prolonged the atrial effective refractory period in both the right and left atria 1 to 4 hours after intraduodenal administration without prolongation of the corrected QT interval, whereas sotalol at 5 mg/kg prolonged both the atrial effective refractory period and the corrected QT interval. Acacetin prevented AF induction at doses of 2.5 mg/kg (50%), 5 mg/kg (85.7%), and 10 mg/kg (85.7%). Sotalol 5 mg/kg also prevented AF induction (60%).

CONCLUSIONS

The present study demonstrates that the natural compound acacetin is an atrium-selective agent that prolongs the atrial effective refractory period without prolonging the corrected QT interval and effectively prevents AF in anesthetized dogs after intraduodenal administration. These results indicate that oral acacetin is a promising atrium-selective agent for the treatment of AF.

Behavioral study of calorie-restricted rats from early old age

PURPOSE

To investigate the effect of Calorie Restriction (CR) on learning and memory ability of early aged rats.

METHODS

18-month rats were subjected to restricted intake by 60% comparing with that of rats fed ad libitum (AL) for 6 months. We compared the overall health status, including survival rate and locomotor activity by open-field test. We examined the spatial cognition ability of the rats by Morris Water Maze.

RESULTS

Our results showed that CR rats had higher survival rate and spontaneous locomotor activity compared with AL rats. CR rats slowed the inability of spatial learning and reference memory.

CONCLUSION

These findings demonstrated that CR in early old rats delayed the declination of spatial cognition.

Modafinil exerts a dose-dependent antiepileptic effect mediated by adrenergic α1 and histaminergic H1 receptors in mice

Epilepsy is characterized by neuronal hyperexcitability and hypersynchronization. Disruption of electroencephalographically (EEG) synchronized epileptiform discharges may be a possible therapy for epilepsy. In the present study, to clarify the role of EEG desynchronization on epilepsy, we investigated the effect of modafinil, a potent wake-promoting substance with EEG desynchronization activity, on epilepsy in mice and clarified the receptors involved in the suppression of seizure caused by maximal electroshock (MES) and pentylenetetrazol (PTZ) kindling models. Modafinil given at 22.5, 45, and 90 mg/kg, i.p. significantly decreased the incidence of tonic hindleg extension in MES seizure models, and protected against PTZ-induced convulsive behaviors in a dose-dependent manner. In addition, modafinil at 180 mg/kg exerted an antiepileptic effect in the MES model; however, at the same dosage it increased the seizure stage in the PTZ-kindling model. The antiepileptic effect in both MES and PTZ models was antagonized by the adrenergic alpha(1) receptor antagonist terazosin, but not by the adrenergic alpha(2) receptor antagonist yohimbine or by dopaminergic receptor antagonists, SCH-23390 (for D(1) receptors) and haloperidol (for D(2) ones). Pyrilamine, a histaminergic H(1) receptor antagonist, counteracted the antiepileptic action of modafinil in the PTZ induced-kindling model, but not in the MES seizure model. Taken together, the present findings indicate that modafinil exerted its antiepileptic effect via adrenergic alpha(1) and histaminergic H(1) receptors, and might be of potential use in the treatment of epilepsy.

Activity and allelopathy of soil of flavone o-glycosides from rice

Two flavone O-glycosides were isolated from allelopathic rice seedlings and have been identified as 5,4'-dihydroxy-3',5'-dimethoxy-7-O-beta-glucopyranosylflavone and 7,4'-dihydroxy-3',5'-dimethoxy-5-O-beta-glucopyranosylflavone. Considerable levels of these glycosides could be found in allelopathic rice tissues. They could not be detected in the soils growing these allelopathic rice seedlings. Only their aglycone, 5,7,4'-trihydroxy-3',5'-dimethoxyflavone, could be found in the soil. Further experiments showed that two flavone O-glycosides were exuded from allelopathic rice roots to the rihzosphere and then transformed into their aglycone form, that is, 5,7,4'-trihydroxy-3',5'-dimethoxyflavone, with a great diversity of biological activities on associated weeds and microbes by soil interactions once released. The glycosides degraded rapidly (t1/2 < 2 h), whereas their aglycone was more resistant toward degradation in paddy soils, in which the half-life (t1/2) at low (25 mug/g) and high (200 mug/g) doses reached 19.86 +/- 3.64 h (r 2 = 0.97) and 28.78 +/- 3.72 h (r 2 = 0.98), respectively. Furthermore, the mobility of both glycosides and their aglycone in paddy soil was evaluated by soil TLC with bioassay. The mobility of the glycosides (Rf = 0.418 +/- 0.069, n = 18) is higher than that of the aglycone (Rf = 0.361 +/- 0.048, n = 18). The results suggested that two flavone O-glycosides are formed in rice biosynthesis and that storage of the allelochemicals and their aglycone 5,7,4'-trihydroxy-3',5'-dimethoxyflavone is the agent of alleloapthic rice which interferes with weeds or microbes in paddy soil.

Characterization of HLA-B*5516, -B*1313, -B*9512, and -DRB1*1457 alleles identified in a southwest Chinese population

The human leukocyte antigen (HLA)-B*5516 allele differs from the B*5502 by a single 97 T --> C substitution (His to Tyr at position 33) in exon 2. The B*1313 allele results from 419 T --> A and 420 A --> C substitutions, encoding a Leu to Tyr substitution at 140 in exon 2 of the B*1301 allele. The B*9512 allele differs from B*1502 by a single 360 G --> C substitution (Gln to His at 120) in exon 3. The DRB1*1457 allele appears to be a hybrid molecule generated by recombination between the DRB1*13 and DRB1*14 alleles. The serological equivalents of these new alleles are HLA-B22, -B13, -B15, and DR13, respectively. Family studies detected two rare haplotypes: A*11, B*9512, DRB1*14 and A*24, B*52, Cw*07, DRB1*1457, DRB3*020201, DQB1*050301. The gene frequencies of these alleles in the Chinese population are less than 0.0001.

Identification of Y118 Amino Acid Residue in Candida albicans Sterol 14.ALPHA.-Demethylase Associated with the Enzyme Activity and Selective Antifungal Activity of Azole Analogues

Our previous publication established a model to predict that the phenyl group of the C-3 side chain of azole antifungal compounds interacts with the phenol group of Tyr118 through the formation of pi-pi face-to-edge interaction. To verify this prediction, wild type and three site-directed mutants of the Y118 residue of Candida albicans sterol 14alpha-demethylase P450 (CACYP51) were constructed and heterologously expressed in Saccharomyces cerevisiae with deletion of the CYP51 gene. With the strains obtained and microsome enzymes separated, cell susceptibility and CACYP51 activity were examined with the 5 novel azole compounds based on the molecular modeling in comparison with fluconazole. After alteration of Y118 with Y118A, Y118F, and Y118T by a single base substitution, the expression levels of CACYP51 protein were not affected. However, these mutations markedly decreased its catalytic activity respectively; the mutation changes also decreased azole susceptibility, indicating the structural importance of the Y118 residue in maintaining CACYP51 activity and in determining azole susceptibility. In addition, our synthetic compounds with the phenyl group side chain attached to C3 produced higher susceptibility against S. cerevisiae with expression of CACYP51 and exhibited more potent inhibitory effects on CACYP51 activity in comparison with fluconazole, suggesting that the phenyl group of C3 side chain substitutes is also important for selective binding to target enzymes.

Development changes of cuticular hydrocarbons in Chrysomya rufifacies larvae: potential for determining larval age

Age determination is the basis of determining the postmortem interval using necrophagous fly larvae. To explore the potential of using cuticular hydrocarbons for determining the ages of fly larvae, changes of cuticular hydrocarbons in developing larvae of Chrysomya rufifacies (Macquart) (Diptera: Calliphoridae) were investigated using gas chromatography with flame-ionization detection and gas chromatography-mass spectrometry. This study showed that the larvae produced cuticular hydrocarbons typical of insects. Most of the hydrocarbons identified were alkanes with the carbon chain length of 21-31, plus six kinds of alkenes. The hydrocarbon composition of the larvae correlated with age. The statistical results showed that simple peak ratios of n-C29 divided by another eight selected peaks increased significantly with age; their relationships with age could be modelled using exponential or power functions with R(2) close to or > 0.80. These results suggest that cuticular hydrocarbon composition is a useful indicator for determining the age of larval C. rufifacies, especially for post-feeding larvae, which are difficult to differentiate by morphology.

Relationship between common functional polymorphisms of the p22phox gene (-930A > G and +242C > T) and nephropathy as a result of Type 2 diabetes in a Chinese population

OBJECTIVE

Genetic determinants are important in diabetic nephropathy (DN). Oxidative stress has also emerged as an important pathogenic factor in DN and vascular NADH oxidase is a major source of reactive oxygen species (ROS). Previous small studies reported a strong but contradictory association between functional genetic variation of p22(phox), an important subcomponent of NADH oxidase, and DN. We investigated the association between two common functional single nucleotide polymorphisms (SNPs) (-930 A > G and +242 C > T) and DN in a much larger group of Chinese patients with Type 2 diabetes mellitus (T2DM).

RESEARCH DESIGN AND METHODS

Case-control study of Chinese subjects with long-standing T2DM (> 10 years). Cases (n = 306) were subjects with a spot urinary albumin : creatinine ratio (ACR) of > 113 mg/mmol or elevated serum creatinine. Control subjects (n = 306) had ACR < 3.3 mg/mmol and normal serum creatinine. Genotyping was carried out by standard PCR and restriction fragment length polymorphism analysis.

RESULTS

Gender distribution, age, duration of diabetes and HbA(1c) were similar in cases and control subjects. Distribution of genotypes in the control subjects for both SNPs was consistent with the Hardy-Weinberg equilibrium. Distribution of genotypes did not differ significantly between cases and control subjects for both polymorphisms-+2424C > T: cases CC 84.6%, CT 15.0%, TT 0.4% and control subjects CC 87.6%, CT 11.8%, TT 0.6% (P = 0.45); -930 A > G: cases AA 40.5%, AG 41.8%, GG 17.7% and control subjects AA 38.2%, AG 49.0%, GG 12.8% (P = 0.12). Distribution of alleles was also similar-+2424 C > T: cases C 92.2%, T 7.8% and control subjects C 93.5%, T 6.5% (P = 0.66); -930 A > G cases A 61.4%, G 38.6% and control subjects A 62.7%, G 37.3% (P = 0.38). We estimated that our study has approximately 80% power to detect a relative risk of 1.65 (for +242 C > T) and 1.35 (for -930 A > G) conferred by the minor allele, respectively.

CONCLUSIONS

In contrast with previous small studies, our data suggest that these SNPs do not confer significantly increased susceptibility to DN secondary to T2DM in Chinese subjects.

Genetic profile of 15 STR loci in the Min Nan population in Southeast China

Genetic profile of 15 short tandem repeats (STR) loci were determined in a Chinese Han population from the Min Nan mountainous area, Southeast China.

SVM classification of human intergenic and gene sequences

Despite constant improvement in prediction accuracy, gene-finding programs are still unable to provide automatic gene discovery with the desired correctness. This paper presents an analysis of gene and intergenic sequences from the point of view of language analysis, where gene and intergenic regions are regarded as two different subjects written in the four-letter alphabet {A,C,G,T}, and high frequency simple sequences are taken as keywords. A measurement alpha(l(tau)) was introduced to describe the relative repeat ratio of simple sequences. Threshold values were found for keyword selections. After eliminating 'noise', 178 short sequences were selected as keywords. DNA sequences are mapped to 178-dimensional Euclidean space, and SVM was used for prediction of gene regions. We showed by cross-validation that the program we developed could predict 93% of gene sequences with 7% false positives. When tested on a long genomic multi-gene sequence, our method improved nucleotide level specificity by 21%, and over 60% of predicted genes corresponded to actual genes.

Numerical study of nonlinear pulsatile flow in S-shaped curved arteries

The nonlinear pulsatile blood flow in S-shaped curved arteries was studied with finite element method. Numerical simulations for flows in two models of S-shaped curved arteries with different diameters and under the same boundary conditions were performed. The temporal and spatial distributions of hemodynamic variables during the cardiac cycle such as velocity field, secondary flow, pressure, and wall shear stresses in the arteries were analyzed. Results of numerical simulations showed that the secondary flow in the larger S-shaped curved artery is more complex than that in the smaller one; stronger eddy flow occurred in the inner bends of curved arteries; pressure and wall shear stresses changed violently in the curved arteries, especially in the larger model. These hemodynamic variables in curved arteries will cause important effects on the function of arterial endothelium in the region. For instance, they may lead to the proliferation of smooth muscle cells and the thickening of the intima, and cardiovascular diseases such as atherosclerosis may develop in such regions. Due to having the special blood flow characteristics in the S-shaped arteries, it is worthwhile to study flow in this kind of curved artery. The comprehensive theoretical foundation showed in the present study can be extended to approach problems of nonlinear pulsatile flow in curved arteries with more complex geometrical shape.

The kinetic model and simulation of blood coagulation—the kinetic influence of activated protein C

The paper described a limited part of the coagulation pathway, and in particular the inhibitory effects of activated protein C in the context of thrombin production. This is a computational modeling study with various assumption made of kinetic rates laws and their summation. The level of complexity and assumed parameters makes conclusions uncertain. However, an interesting outcome is that kinetic reaction rates may show oscillation behavior under particular, high levels of protein C feedback inhibition. The model would defy quantitative practical use, but could have predictive value as a qualitative descriptor of coagulation.

Method for the control of NOx emissions in long-range space travel

The wheat straw, an inedible biomass that can be continuously produced in a space vehicle has been used to produce activated carbon for effective control of NOx emissions from the incineration of wastes. The optimal carbonization temperature of wheat straw was found to be around 600 degrees C when a burnoff of 67% was observed. The BET surface area of the activated carbon produced from the wheat straw reached as high as 300 m2/g. The presence of oxygen in flue gas is essential for effective adsorption of NO by activated carbon. On the contrary, water vapor inhibits the adsorption efficiency of NO. Consequently, water vapor in flue gas should be removed by drying agents before adsorption to ensure high NO adsorption efficiency. All of the NO in the flue gas was removed for more than 2 h by the activated carbons when 10% oxygen was present and the ratio of carbon weight to the flue gas flow rate (W/F) was 30 g min/L, with a contact time of 10.2 s. All of NO was reduced to N2 by the activated carbon at 450 degrees C with a W/F ratio of 15 g min/L and a contact time of 5.1 s. Reduction of the adsorbed NO also regenerated the activated carbon, and the regenerated activated carbon exhibited an improved NO adsorption efficiency. However, the reduction of the adsorbed NO resulted in a loss of carbon which was determined to be about 0.99% of the activated carbon per cycle of regeneration. The sufficiency of the amount of wheat straw in providing the activated carbon based on a six-person crew, such as the mission planned for Mars, has been determined. This novel approach for the control of NOx emissions is sustainable in a closed system such as the case in space travel. It is simple to operate and is functional under microgravity environment.

[Effect of tumor necrosis factor-alpha on differentiation of mesencephalic neural stem cells and proliferation of oligodendrocytes in the rat]

To observe the influence of tumor necrosis factor-alpha (TNF-alpha) on differentiation of rat mesencephalic neural stem cells (NSCs), the numbers of neurons, astrocytes and oligodendrocytes generated from NSCs were analyzed after differentiation for 3 days by using immunocytochemistry technique. The results show that: (1) TNF-alpha enhanced the proportions of neurons and oligodendrocytes in progeny of NSCs; and (2) TNF-alpha induced the proliferation of oligodendrocytes derived from NSCs, but the proliferation of astrocytes was not influenced by TNF-alpha. We conclude that the TNF-alpha could influence the application of NSCs.

The Use of Rice Hulls for Sustainable Control of NOx Emissions in Deep Space Missions

The use of the activated carbon produced from rice hulls to control NOx emissions for future deep space missions has been demonstrated. The optimal carbonization temperature range was found to be between 600 and 750 degrees C. A burnoff of 61.8% was found at 700 degrees C in pyrolysis and 750 degrees C in activation. The BET surface area of the activated carbon from rice hulls was determined to be 172 m2/g when prepared at 700 degrees C. The presence of oxygen in flue gas is essential for effective adsorption of NO by activated carbon. On the contrary, water vapor inhibits the adsorption efficiency of NO. Consequently, water vapor in flue gas should be removed by drying agents before adsorption to ensure high NO adsorption efficiency. All of the NO in the flue gas was removed for more than 1.5 h when 10% oxygen was present and the ratio of the carbon weight to the flue gas flow rate (W/F) was 15.4 g min/L. Reduction of the adsorbed NO to form N2 could be effectively accomplished under anaerobic conditions at 550 degrees C. The adsorption capacity of NO on the activated carbon was found to be 5.02 mg of NO/g of carbon. The loss of carbon mass was determined to be about 0.16% of the activated carbon per cycle of regeneration if the regeneration occurred when the NO in the flue gas after the carbon bed reached 4.8 ppm, the space maximum allowable concentration. The reduction of the adsorbed NO also regenerated the activated carbon, and the regenerated activated carbon exhibited an improved NO adsorption efficiency.

Toll-like receptor-4 is expressed by macrophages in murine and human lipid-rich atherosclerotic plaques and upregulated by oxidized LDL

BACKGROUND

Inflammation is implicated in atherogenesis and plaque disruption. Toll-like receptor 2 (TLR-2) and TLR-4, a human homologue of drosophila Toll, play an important role in the innate and inflammatory signaling responses to microbial agents. To investigate a potential role of these receptors in atherosclerosis, we assessed the expression of TLR-2 and TLR-4 in murine and human atherosclerotic plaques.

METHODS AND RESULTS

Aortic root lesions of high-fat diet-fed apoE-deficient mice (n=5) and human coronary atherosclerotic plaques (n=9) obtained at autopsy were examined for TLR-4 and TLR-2 expression by immunohistochemistry. Aortic atherosclerotic lesions in all apoE-deficient mice expressed TLR-4, whereas aortic tissue obtained from control C57BL/6J mice showed no TLR-4 expression. All 5 lipid-rich human plaques expressed TRL-4, whereas the 4 fibrous plaques and 4 normal human arteries showed no or minimal expression. Serial sections and double immunostaining showed TLR-4 colocalizing with macrophages both in murine atherosclerotic lesions and at the shoulder region of human coronary artery plaques. In contrast to TLR-4, none of the plaques expressed TLR-2. Furthermore, basal TLR-4 mRNA expression by human monocyte-derived macrophages was upregulated by ox-LDL in vitro.

CONCLUSIONS

Our study demonstrates that TLR-4 is preferentially expressed by macrophages in murine and human lipid-rich atherosclerotic lesions, where it may play a role to enhance and sustain the innate immune and inflammatory responses. Moreover, upregulation of TLR-4 in macrophages by oxidized LDL suggests that TLR-4 may provide a potential pathophysiological link between lipids and infection/inflammation and atherosclerosis.

[Mass optimization of thermal network model of coupled dual-loop thermal control system in spacecraft]

OBJECTIVE

To deal with the mass optimization of thermal control system as well as environmental control and life support system (ECLSS) of manned spacecraft.

METHOD

The thermo-hydraulic network composed of coupled liquid dual-loop and gas loops was studied. Physical and mathematical models were established and used for flow, heat transfer and mass calculation in the network. The influences of various operational and structural parameters on the mass were analyzed.

RESULT

There were optimal pipe diameters for internal loop and external loop; there existed an upper limit of flow rate in the internal loop and lower limit in the external loop; there were also optimal flow rates in the loops and optimal exit temperature of the radiator.

CONCLUSION

Reasonable design of these parameters were very important for reducing the system mass.

Novel solution-phase immunoassays for molecular analysis of tumor markers

at 3 x 10(9) M(-1) and a step-wise binding process with PSA-free MAB. Thus, this solution-phase quantitative ECL immunoassay allowed measurement of the affinity of serum PSAs with their MABs and screening of PSAs based upon their affinity to MABs. Unlike other immunoassays, this immunoassay demonstrated one-step rapid analysis while simultaneously eliminating immobilization, separation and washing steps and detected PSA at a level of 1.7 pg mL(-1), which is 1000-fold more sensitive than current PSA immunoassays. Furthermore, single-molecule (SM) phosphorescence microscopy was developed to detect single serum PSA-free and PSA-complex molecules in solution with no use of antibody showing that PSA-free molecules diffused faster than PSA-complex molecules in solution. This finding is consistent with ECL measurements and implies the possibility of screening individual analytes in a complex mixture using their distinct SM diffusion distance. This is the first report describing the detection of single protein molecules labeled with a metal-complex using phosphorescence microscopy and also the screening of serum tumor markers using ECL and SM phosphorescence solution-phase assays.

[Optimization analysis of ventilation and dehumidification in manned spacecraft]

OBJECTIVE

To achieve the optimized design of system operational parameters and system components in air ventilation and dehumidification of manned spacecraft.

METHOD

Mathematical-physical model of air ventilation and dehumidification system was established. Through the design of optimal operational parameters for system performance, heat and moisture in the cabin of manned spacecraft could be removed effectively, dewing could be prevented, and the comfort demand of the astronauts could be met. Equivalent mass of the system in different operational parameters and system components was analyzed by calculation.

RESULT

The dew point temperature and the comfortability depended on the temperature and humidity of the influx, ventilation rate, and evaporation of moisture in the cabin. There were two ways to control the operational parameters of air ventilation and dehumidification system. The method based on controlling temperature didn't use recuperative heat exchangers in the loop, and the system structure for the design was simple, but it didn't meet the requirement of dissipating moisture in some conditions. The other method was based on controlling the moisture, and it could steadily keep the dew point temperature in the cabin and control the occurrence of dew. But the system structure of this design was relatively complex.

CONCLUSION

Mass and power consumption of the system could be reduced by selecting appropriate parameters and adopting the measures of optimization.

Primary study of vascular endothelial growth factor immunohistochemical staining in the diagnosis of early acute myocardial ischemia

The expression of vascular endothelial growth factor (VEGF) in the model of rat early acute myocardial ischemia was studied by Strept-Avidin-Biotin-Peroxidase Complex (SABC) immunohistochemical staining. After ligating the anterior descending branch of the left coronary artery, an initial rapid (30min) positive expression of VEGF in myocardial ischemic areas was observed, the intensity of positive expression of VEGF increased with the continuation of myocardial ischemia. After 5h infarction, the strongly positive myocytes of SABC-VEGF staining were predominantly limited to perimyocardial infarction areas. No positive expression of VEGF was found in the control group. These findings suggested that SABC-VEGF method could give a sensitive, specific, simple and objective morphologic evidence to the diagnosis of sudden cardiac death caused by acute early myocardial ischemia.