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The non-dispersive infrared (NDIR) instruments are widely applied to multicomponent gas detection in many fields. In this paper, a NDIR instrument using the galvanometer modulation is proposed, which has a common optical path for multicomponent gas detection. Compared with the conventional NDIR instrument using the chopper modulation, the proposed instrument with a simpler configuration has better detection efficiency and stability. The proposed instrument has been successfully used to measure the main gas components of vehicle emissions. The NDIR instrument using the galvanometer modulation has great potential for remote sensing application, where multicomponent gas is always spatially inhomogeneous. [ABSTRACT FROM AUTHOR]

Superhydrophobic surfaces were prepared on Cu substrates via a facile surface oxidation approach and subsequent chemical modification with low surface energy materials. In this paper, antiformin solution, as one of the most commonly used low cost disinfectants, is introduced for preparing bionic microstructures on copper surfaces for the first time. A short-time oxidation reaction soaking the Cu foil in antiformin liquid can result in the formation of a bean sprout-like structure. Moreover, regulating the morphology of the microstructure can be realized by changing the reaction duration and solution concentration under a wide range of experimental conditions. A possible growth mechanism is also proposed here. After being modified by stearic acid, all as-etched surfaces possess superhydrophobic properties, with a water contact angle (CA) larger than 150° and a sliding angle (SA) less than 10°. Simultaneously superoleophobic interfaces can be obtained after the etched surfaces are modified with heptadecafluorodecyltrimethoxysilane (HTMS). The resultant samples present good thermal stability at ambient temperatures below 150 °C. The same approach is also suitable for brass materials. This offers an effective and practical route for large scale industrial production of superhydrophobic materials. [ABSTRACT FROM AUTHOR]

In this study, forty celery cultivars introduced from different regions of China were used as experimental materials to verify and analyze the practicability of RAPD technology in the identification of celery cultivars. The results showed that RAPD technology could distinguish accurately the genetic relationship among various celery cultivars as a simple and ideal DNA molecular marker technology suitable for genetic relationship analysis. To be specific, 13 RAPD primers with clear amplified bands and significantly different number of amplified bands were screened, which provided basis for the identification of genetic relationship among different celery cultivars. [ABSTRACT FROM AUTHOR]

Cerebral venous thrombosis (CVT) is a rare and potential fatal disease, which comprises the occlusion of the flow in the cerebral venous system and its sinuses. Electroencephalogram (EEG) characteristics can be analyzed to investigate the applied value in the assessment of cognitive impairment of the CVT patients. 100 patients (including cognitive impairment patients (CI) and cognitive normality patients (NCI)) with CVT and 50 normal health persons (CN) were received from January 2009 to January 2011 at the department of Neurology. All above of the subjects were analyzed by EEG. The EEG analyses results were compared with the MoCA scale with the methods of correlation analyses, clustering analyses and concordance analyses. The results indicated that CI patients had significantly lower EEG beta power relative to NCI or CN group (both P<0.05), but no difference was found between NCI and CN group (P>0.05). There was a better concordance (Kappa=0.837) between the beta power and MoCA scoring for CVT patients. No significant differences were discovered between beta power analyses and MoCA scoring method for the cognitive impairment post CVT (P=0.297). In conclusion, the EEG beta power analyses technique may hold a considerable promise for the early assessment of cognitive impairment post CVT. [ABSTRACT FROM AUTHOR]

Background: Malignant glioma is a common primary tumor of the central nervous system. Brevican, an abundant extracellular matrix component in the adult brain, plays a critical role in the process of glioma. The mechanisms for the highly invasive behavior of gliomas are still poorly understood. The aim of this study was to examine whether brevican is a predictor of glioma and its roles in glioma cell motility. Methods: In this study, immunohistochemistry staining for brevican expression was performed in malignant gliomas and benign controls. We also explored the effects of brevican on cell adhesion and migration in brevican-overexpressed cells. Knockdown of brevican expression was achieved by stable transfection of U251 cells transduced with a construct encoding a short hairpin DNA directed against the brevican gene, which correspondingly, down-regulated the proliferation, invasion and spread of brevican-expressing cells. Moreover, the role of brevican in the growth and progression of glioma was demonstrated by in vivo studies. Results: Our results provide evidence for the molecular and cellular mechanisms that may underlie the motility-promoting role of brevican in the progression of glioma. The role of brevican as a target for immunotherapy might be taken into consideration in future studies. Conclusions: This study suggests that expression of brevican is associated with glioma cell adhesion, motility and tumor growth, and also is related to glioma cell differentiation, therefore it may be a marker for malignance degree of glioma. [ABSTRACT FROM AUTHOR]

Nonviral cationic polymers like chitosan can be combined with DNA to protect it from degradation. The chitosan is a biocompatible, biodegradable, nontoxic, and cheap polycationic polymer with low immunogenicity. The objective of this study was to synthesize and then assess different chitosan-DNA nanoparticles and to select the best ones for selective in vitro transfection in human epidermoid carcinoma (KB) cell lines. It revealed that different combinations of molecular weight, the presence or absence of folic acid ligand, and different plasmid DNA sizes can lead to nanoparticles with various diameters and diverse transfection efficiencies. The intracellular trafficking, nuclear uptake, and localization are also studied by confocalmicroscopy, which confirmed that DNA was delivered to cell nuclei to be expressed. [ABSTRACT FROM AUTHOR]

Interleukin-1 receptor antagonist (IL-1Ra), is a natural blocker of the inflammatory cytokine interleukin-1. Using a rat adjuvant-induced arthritis (AIA) model of rheumatoid arthritis (RA), we examined the protective effects of IL-1Ra in bone metabolism in vivo after folate-mediated nonviral gene delivery. We detected secreted human IL-1Ra protein in serum and cultured primary osteoblasts of rats that were treated with chitosan–IL-1Ra and folate–IL-1Ra–chitosan nanoparticles, respectively. In vivo, IL-1Ra gene delivery significantly reverted alterations in bone turnover observed in arthritic animals by modulating the level of osteocalcin (OC) as well as the activities of alkaline phosphatase and tartrate-resistant acid phosphatase. The protective effects of these nanoparticles were evident from the decrease in the expression levels of interleukine-1β and prostaglandin E2 as well as osteoclast number and other histopathological findings. Compared to naked DNA and chitosan–DNA, folate–chitosan–DNA nanoparticles were less cytotoxic and enhanced IL-1Ra protein synthesis in vitro and offered a better protection against inflammation and abnormal bone metabolism in vivo. Nonviral gene therapy with folate–chitosan–DNA nanoparticles containing the IL-1 Ra gene seemed to protect against bone damage and inflammation in rat adjuvant-induced arthritis model.Molecular Therapy (2008) 16 7, 1243–1251 doi:10.1038/mt.2008.99 [ABSTRACT FROM AUTHOR]

Sintered rare-earth permanent magnets (for example, Sm2 Co17, SmCo5, and Nd2 Fe14B magnets) are quite brittle and easily crack in the course of fabrication, machining, and application. Here, we report on an investigation of fracture behavior and mechanical characteristics of sintered rare-earth permanent magnets and discuss the origin of rare-earth magnet brittleness. We studied three groups of bending specimens with different orientations, cut from the same block of magnet The bending strength was measured. The fracture surfaces were carefully observed by scanning electron microscopy and showed that the fracture behavior and bending strength of Sintered rare-earth permanent magnets obviously exhibit anisotropy. Sintered Sm-Co magnets tend to cleavage fracture in the close-packed (0001) plane or in the (1011) plane. The fracture mechanism of sintered Nd2 Fe14 B magnet appears to be mainly intergranular fracture. Our analysis indicates that the anisotropy of fracture behavior and mechanical strength of sintered rare-earth magnets is caused by the strong crystal-structure anisotropy and grain texture created by magnetic field alignment during the fabrication process. [ABSTRACT FROM AUTHOR]

Bleomycin is a small glycopeptide antibiotic used in combination therapy for the treatment of a few types of human cancer. The antitumor effect of bleomycin is most likely caused by its ability to bind to DNA and induce the formation of toxic DNA lesions via a free radical reactive (Fe.bleomycin) complex. However, the chemotherapeutic potential of bleomycin is limited, as it causes pulmonary fibrosis and tumor resistance at high doses. The chemical structure and modes of action of bleomycin have been extensively studied and these provide a foundation towards improving the therapeutic value of the drug. This review provides a first account of the current state of knowledge of the cellular processes that can allow the yeast Saccharomyces cerevisiae to evade the lethal effects of bleomycin. This model organism is likely to provide rapid clues in our understanding of bleomycin resistance in tumor cells. [ABSTRACT FROM AUTHOR]

Characterizes the extracellular lipase encoded by LIP2 in the lipolytic yeast Yarrowia lipolytica. Influence of pro region on lipase secretion and activity; Regulation of extracellular lipase activity by expression of the LIP2 gene; Information on alternative pathway for triglyceride utilization in Y. lipolytica.

Sintered Sm2 Co17 magnets are widely used in aviation, spaceflight and precision instruments, etc. Thermal expansion coefficients a are necessary engineering data for the precision applications of the magnets (α presents the average thermal expansion coefficient). Here, we report an investigation on thermal expansion of sintered Sm2CO17 magnets. The effects of the substitutions of Gd, Dy, Er, and Pr for Sm on thermal expansion characteristics were discussed, respectively. The thermal expansion characteristics were measured using a NETZSCH DIL 402C thermal dilatometer. α// is the thermal expansion coefficient in the c axis and α⊥ is the coefficient in the base plane. All the specimens for each material were cut from the same block. A scanning electronic microscope (SEM) equipped with an energy dispersive x-ray analysis system is employed to observe the microstructure. It shows that the thermal expansion coefficient of Sm2Co17 magnets obviously exhibit anisotropy. The α⊥ is higher than the α//. The thermal expansion coefficient (both α⊥ and α//) increases and the thermal expansion anisotropy (α⊥ - α//) decreases with increasing temperature. The substitutions of heavy-rare earth elements, such as Gd+Dy, and Er decrease α//, the substitution of Pr for Sm moderately increases α//. The phenomenon is especially obvious in low-temperature range. [ABSTRACT FROM AUTHOR]

The computed tomography image spectrometer (CTIS) is a snapshot hyperspectral imaging technique, which enables hyperspectral image acquisition in a dynamic scene. However, traditional image reconstruction methods with no explicit constraints will introduce high-frequency noise. The low-rank property has been used in hyperspectral image denoising and achieved great effects. We develop an effective method of low-rank estimation (LRE) for CTIS image reconstruction, which shows significant improvements in both the image quality and the spectral quality of the reconstructed image. Compared with the traditional methods, the peak signal-to-noise ratio of the LRE hyperspectral image can be increased by 8 dB, and the spectral-angular mapping can be decreased by 4 times. [ABSTRACT FROM AUTHOR]

Although the blockade of the programmed cell death protein 1/programmed cell death ligand 1 (PD-1/PD-L1) pathway has become a promising treatment strategy for several types of cancers, the constitutive activation of c-Met in tumors may cause a low overall response rate to PD-1 inhibitors. Increasing evidence indicates that the dual inhibition of c-Met and PD-1 could improve the efficacy of anti-PD-1/PD-L1 monoclonal antibodies for tumor immunotherapy. In this study, we developed two bispecific single-chain diabodies targeting c-Met and PD-1 for the treatment of solid tumors based on protein homology modeling, and we identified that the binding affinity of diabody-mp to c-Met was 50-folds higher than that of diabody-pm. The results of in vitro studies revealed that both diabodies suppressed HGF-induced proliferation, migration, and invasion of tumor cells, inhibiting the activation of c-Met signaling by antagonizing HGF binding to c-Met. Moreover, they promoted T cell activation by blocking the PD-1 pathway, mediating tumor cellular cytotoxicity through T cell engagement. In vivo studies with mice models demonstrated that diabody-mp exhibited higher therapeutic efficacy than other structural anti-bodies, greatly enhancing the survival of c-Met-positive tumor-bearing mice compared to single or combined c-Met and PD-1 blockade therapy. Furthermore, diabody-mp, which had a higher c-Met binding affinity, showed better anti-tumoral activity than diabody-pm, which had a lower c-Met binding affinity. In conclusion, bispecific anti-PD-1/c-Met diabody-mp, with high c-Met-associated affinity, inhibited tumor growth by activating T cells, suggesting its therapeutic potential for c-Met-positive solid tumors. [ABSTRACT FROM AUTHOR]

CtBP2 has been demonstrated to possess tumor-promoting capacities by virtue of up-regulating epithelial-mesenchymal transition (EMT) and down-regulating apoptosis in cancer cells. As a result, cellular CtBP2 levels are considered a key factor determining the outcome of oncogenic transformation. How pro-tumorigenic and anti-tumorigenic factors compete for fine-tuning CtBP2 levels is incompletely understood. Here we report that the cyclin H/cyclin-dependent kinase 7 (CCNH/CDK7) complex interacted with CtBP2 in vivo and in vitro. Depletion of either CCNH or CDK7 decreased CtBP2 protein levels by accelerating proteasome-dependent CtBP2 clearance. Further analysis revealed that CCNH/CDK7 competed with the tumor repressor HIPK2 for CtBP2 binding and consequently inhibited phosphorylation and dimerization of CtBP2. Phosphorylation-defective CtBP2 interacted more strongly with CCNH/CDK7 and was more resistant to degradation. Finally, overexpression of CtBP2 increased whereas depletion of CtBP2 dampened the invasive and migratory potential of breast cancer cells. CtBP2 promoted the invasion and migration of breast cancer cells in a CCNH-dependent manner. Taken together, our data have delineated a novel pathway that regulates CtBP2 stability, suggesting that targeting the CCNH/CDK7-CtBP2 axis may yield a viable anti-tumor strategy. [ABSTRACT FROM AUTHOR]

Objective: To clarify the relationship between helicobacter pylori (Hp) infection, tongue manifestation and gastroscopic manifestation, and explore the mechanism of action of "oral-gastric microecology" in the occurrence and development of stomach-related diseases., Medhods: A total of 1100 patients were divided into Hp positive group and Hp negative group according to 13C breath test results. The tongue manifestation materials from patients were collected to make tongue printing slides for morphological observation of exfoliative cells from tongue coating, and electronic gastroscopy was performed on the patients and the data was analyzed., Results: Hp infection rate was about 45.95%; and the greasy coating was mostly observed in Hp positive group (63.14%, 0.05). The total tongue coating distribution was as follows: yellow greasy coating (56.66%, 0.05) > yellow coating > white coating > white greasy coating. The gastric mucosal roughness and mucosal hematoplastic plaques in the two groups were more common in the Hp positive group ( 0.05). There was a significant difference in the granular subgroup and in the rough mucosal group (< 0.05)., Conclusions: Hp infection is more commonly observed in yellow greasy coating, and this can be used as a reference for Traditional Chinese Medicine in determining whether it is Hp infection or not. Mucosal granule roughness, hyperemia, and oral Hp showed association with Hp infection in the stomach and interacted with micro-ecological environment that is composed of the oral cavity.