An Antibacterial Wound Dressing Based on GS-SF Composite Scaffold

Although the treatment of burn wounds has made great progress, the incidence of wound infection is still the main cause of high mortality. In this study, a silk fibroin (SF) scaffold wound dressing incorporated with Gentamicin Sulfate (GS) was developed for the treatment of burn infected wounds, in which GS was used as anti-bacterial agent. GS was mixed with silk fibroin solution and then processed into GS-SF composite scaffold via electro-spinning. The results showed the scaffold exhibited uniform polyporous morphology with 80% porosity. Induced by methanol, the scaffold presented much improved mechanical properties and stability to protease XIV. More important, the scaffold presented significant growth inhibition on both Gram-positive (Staphylococcus aureus) and Gram-negative (Pseudomonas aeruginosa and Escherichia coli) bacteria.

The Influence of Caldesmon Suppression on Proliferation and Motilities of Vascular Smooth Muscle Cells

Migration of vascular smooth muscle cells (VSMCs) from the media to intima constitutes a critical step in the development of proliferative vascular diseases. To elucidate the regulatory mechanism of VSMCs motility, the roles of caldesmon (CaD) were investigated previously. CaD is an actin-binding protein dynamically regulating cytoskeleton structure. In this study, the potential role of CaD in mediating proliferation and motility of VSMCs were discussed. First, structural effect of CaD on cytoskeleton integrity was analyzed with CaD knock-down;second, the proliferation of VSMCs was measured in CaD knock-down and control cells;third, the specific role of CaD on VSMCs motilities was evaluated with in vitro migration and invasion assays. We found that CaD is an integral component to maintain cytoskeleton integrity of VSMCs. Our data indicated that CaD suppression does not show significant influence on VSMCs proliferation, but negatively modulates the motilities of VSMCs, and CaD depletion would significantly facilitate migration and invasion of VSMCs.

An event-related potential observation of preposition processing in Chinese: Is N280 a specific component for Chinese prepositions?

BACKGROUND： Studies have shown that closed-class words, such as prepositions and conjunctions, induce a left anterior negativity （N280）, indicating that N280 should be a specific component of the word category. OBJECTIVE： To observe if Chinese prepositions and verbs exhibit different linguistic functions, to determine whether they are processed by different neural systems, and to verify that N280 is a specific component. DESIGN, TIME AND SETTING： The observed neurolinguistics experiment was performed at Xuzhou Normal University between November and December 2006. PARTICIPANTS： Sixteen undergraduate students, comprising 8 females and 8 males, with no mental or neuropathological history, were selected. METHODS： A total of 15 verbs and prepositions were used as linguistic stimuli, and each verb and preposition was combined to produce four correct phrase collocations and four incorrect ones. MAIN OUTCOME MEASURES： Event-related potentials were recorded in the subjects while they read correct or incorrect phases flashed upon a video screen. RESULTS： Both verbs and prepositions elicited negativity at the frontal site in a 230-330 ms window, as well as at the fronto-temporal and central sites in a 350-500 ms window. Neither exhibited significant differences in peak [F（1, 15） = 0.144, P = 0.710] and latency [F（1, 15） = 0.144, P= 0.710]. Both verbs and prepositions elicited negativity at the left and right hemisphere in a 270-400 ms window. CONCLUSION： There was no significant difference between Chinese prepositions and verbs in the neural system process and N280 was not the specific component for closed-class words.

Strong and Tough PAm/SA Hydrogel with Highly Strain Sensitivity

The hydrogel is a preferred material for flexible wearable sensors.In practical application,it should have high-efficiency mechanical toughness and self-healing performance.Besides,hydrogel requires good affinity and adhe-sion because of its contact with the skin.In this experiment,we made an ultra-tough hydrogel with excellent cell affinity and adhesion.We used sodium alginate(SA)and polyacrylamide(PAm)mixture as a flexible base fluid.Polydopamine reduce graphene oxide(prGO)was used as conductive nanofiller,and then PAm-prGO-SA semi-interpenetrating network hydrogel was formed through Am radical polymerization.The presence of prGO endows the hydrogels with excellent electrical conductivity.Simultaneously,some non-reduced GO forms non-covalent cross-links with PAm,SA,and Polydopamine(PDA)in the hydrogel network.The stress of PAm-prGO-SA hydrogel can reach 750 KPa,and the strain is 900%.The hydrogel,combined with its excellent electrical,mechanical properties,and biocompatibility,is expected to be applied in portable,remote,and real-time health monitoring systems.

A Promising Wound Dressing from Regenerated Silk Fibroin Sponge with Sustain-ed Release of Silver Nanoparticles

A silk fibroin(SF)spongy wound dressing incorporated with silver nanoparticles(Ag-NPs)was developed for biomedical applications.Ag-NPs were efficiently synthesized in situ via ultra violet(UV)with AgNO_(3) as precursor and silk fibroin as reducing and protecting agent,respectively.After lyophilization,the formed silk fibroin spongy wound dressing(SFWD)exhibited polyporous morphology and inner lamellae structures,with uniform dispersion of Ag-NPs.The porous structure provided SFWD with the ability to absorb tissue exudatealmost 6 times of its own weight,which could guarantee the sustained release of Ag-NPs.By methanol treatment,SFWD showed much improved mechanical properties and more stable to protease XIV.The cyto-compatibility of SFWD was supported by normal adherence and proliferation of NIH3T3 fibroblasts in sponges extracting culture medium.More important,the SFWD showed significant growth inhibition in both plate culture assays and bacterial suspension assays,with Gram-positive(Staphylococcus aureus)and Gram-negative(Pseudomonas aeruginosa and Escherichia coli).In a cutaneous excisional mouse model,the average healing rates of SFWD was significantly higher than control and commercial bandages.The hematoxylin-eosin(HE)staining results of the wound section also showed that SFWD could recruit more cells and promote tissue formation on the wound edges.

Liquid Crystal Biosensor Based on Cd²⁺Inducing the Bending of PS-Oligo for the Detection of Cadmium

In this study, a novel liquid crystal (LC) biosensor was developed for the highly sensitive and selective detection of Cd2+ based on Cd2+ inducing the bending of PS-oligo. This strategy makes use of the DNA conformational change to enhance the disruption of orientation of LC leading to an amplified optical signal. DNA containing-SH was bound on the glass slide of the LC cell modified with the DMOAP/APTES. The DMOAP can effectively induce the homeotropic alignment of LC. In the presence of Cd2+, Cd2+ can induce DNA to bend and become a 2 nm spherical structure, which can greatly disrupt the orientational arrangement of LC, resulting in the correspond changes of the optical image of LC cell birefringent under the polarizing microscope. When the Cd2+ concentration is low to 0.1 nM, the optical signal of LC biosensor has an obvious change. But in the absence of Cd2+, there is no orientational response of LC and the optical image under the polarizing microscope is still a uniform dark background. Thus, this LC sensing method has a sensitive and clear distinction between positive and negative results and offers a highly sensitive detection of Cd2+ with a low detection limit down to 0.1 nM.

G Protein-Coupled Estrogen Receptor Is a Critical Regulator in Metastasis of Breast Cancer Cells

Estrogen signaling via GPER in breast cancers has been intensively discussed over years, but the underlying molecular mechanism remains to be fully elucidated, especially for the transcriptional profiles of the GPER under estrogen stimulation. In this study, we evaluated the potential role GPER in regulating invasion of metastatic breast cancer cell line MDA-MB-231 via transcriptional way. First, with primary breast cancer tissue samples, we found that the expression of GPER significantly coordinated with another membrane receptor-CXCR1. Besides, the expression level of these two proteins was associated with the development of the primary breast cancers. Second, to dissect the cross talk between GPER and CXCR1, we further our studies to detect the activation of ERK, Akt and transcriptional factor NF-kB. We found that upon estrogen stimulation, the phosphorylation level of ERK and Akt were rapidly increased and then resulted in the activation and nucleus translocation of NF-kB. When we considered the sub-sequence of the NF-kB activation, we found the autocrine of IL-8 was boosted by stimulation of the estrogen and followed by the promoted invasion of the MDA-MB-231 cells. In conclusion, our data demonstrated the estrogen-mediated GPER stimulation would regulate the invasive activities of metastatic breast cancer cell line MDA-MB-231 coupled with another membrane receptor CXCR1 via transcriptional pathway, the cross talk between GPER and CXCR1 may be another target for breast cancer therapies.

Development of a signal collecting system for double-channel auscultation

As is known to all, many auscultations of human body, such as heart, lung and carotid artery sound, play a major role in clinic. And their signal frequency is in the range that computer sound card can handle, so we can use analog-to-digital (A/D) conversion of sound card as A/D conversion (ADC) of auscultation signals, and double-channel auscultation signals (DCASs) can be input into personal computer(PC) by sound card that every computer has, and it makes the hardware design more simple. Because auscultation signals are input from sound card, any common music processing software (CMPS) can be used to process received auscultative signals, and it is not necessary to write special processing software for them. Therefore, only a double-channel and front-end analog signal processing circuit of auscultation is needed to be designed. By this method of constituting the signal collecting system for double-channel auscultation, it is simple and low cost, and needs no special software, so it has very important values and a broad market prospect.

Design and application of computer software for collecting color data about urine reagent strips

Urine analysis is one of the most common and useful assay means in clinic for diagnose disease, especially urinary system disease and dry chemistry method is the most convenient, common and low cost about urine analysis. To expediently and efficiently analyze the corresponding relationships between different color data and semi-quantitative results about every urine item with dry chemistry way, in this paper, the design and application of effective software that may be used to collect color data about urine reagent strips are presented. First, we introduce the design procedure of this software. Second, its realization of design is given. Third, several application examples about collecting RGB original data by RS232 interface are shown. Then, RGB original data can be visually displayed by waveforms or curves and the data of cursor position may also be given. From the examples, we could confidently draw a conclusion that it is very convenient and effective to study on the laws of color variation about reagent pieces on reagent strip and it has met our original designed demands.

Rapid and Non-Invasive Screening System for Early Detection of Diabetic Retinopathy via Auto Fluorescence of <i>Falvin</i>Proteins

Diabetic retinopathy is one of the most serious complications of diabetes, which is also one of the most important causes of blindness around the world. Autofluorescence of flavin protein in retinal pigment epithelial cells is considered as a marker of early tissue damage. This study was designed to image spontaneous fluorescence of falvin proteins in fundus macular center area. The average intensity of the fluorescence signal and the characteristics of the histogram distribution were obtained and the significant differences in the fluorescence signals between the diabetic and the normal people were also compared with statistical methods, and then a rapid and non-invasive screening method and equipment for early detection of diabetic retinopathy were developed.

The Different Effect of R and S Albuterol on Proliferation and Migration of Airway Smooth Muscle Cells

studies have shown that the R- and S-enantiomers of racemic albuterol, a β2-adrenergic receptor agonist used in asthma treatment, have differential effects on the contractile properties of airway smooth muscle. However, the effect of albuterol on the proliferation and migration has never been tested. Since (R)-, but not (S)-albuterol enhances bronchodilation, we expect the two racemic isomers would also affect proliferation and migration of tracheal cells differentially. By monitoring migratory properties of airway smooth muscle cells in the presence of albuterol isomers, the different effect of albuterol on proliferation and migration of airway smooth muscle cells is probed. The results show Both of R- and S-albuterol could inhibit the proliferation of smooth muscle cells and the inhibition ratio of these two isomers had no significant difference;R-albuterol, but not S-albuterol, inhibited cell migration.

Spatial Distribution of Cytoskeletal Mechanical Properties in Vascular Smooth Muscle Cells

The mechanical properties on a whole basis of cell are extensively studied whereas regional mechanical properties of the cytoskeleton (CSK) have not been characterized. To fill this gap, here we provide detailed intracellular maps of regional CSK stiffness and traction forces, as well as the structural rearrangement in vascular smooth muscle cells (VSMCs). We used micropatterning to restrict VSMC to a single island. Regional cell stiffness was measured with optical magnetic twisting cytometry and traction force microscopy was used to measure regional traction forces. Finally, we used F-actin staining to measure the regional F-actin distribution. From traction and cell height data we computed the prestress within a cell using finite element methods. Compared with the cell center, cell edges were systematically stiffer, more fluid-like and supported higher traction forces, and at the same time had slower remodeling dynamics. These findings provide the most detailed characterization to date concerning regional mechanical properties of the intact cytoskeleton.

Colorimetric Detection of Lead Ion Based on Gold Nanoparticles and Lead-Stabilized G-Quartet Formation

In this report, we present a method for the detection of Pb2+ based on the different adsorption capacity on the surface of gold nanoparticles (AuNPs) between ssDNA (single-stranded DNA) and G-quartet. In the absence of Pb2+, the DNA oligonucleotides probe, which is guanine-rich ssDNA, can be adsorbed on the surface of AuNPs protecting them from aggregation. After adding Pb2+, the DNA oligonucleotides probe can specifically form compact G-quartet, which can induce the aggregation of unmodified AuNPs, especially after adding NaCl aqueous solution. Consequently, the color turns from red to blue. Pb2+ can be detected by colorimetric response of AuNPs;its detection limit can reach 5 μM only observed by naked eyes. Most metal ions have no interferences, and the interference of Cu2+ can be effectively eliminated by adding cysteine. It provides a simple and effective colorimetric sensor for on-site and real time detection of Pb2+.

Development of Portable Monitoring System for Real-Time Detection of Fetal Movement

Effective fetal monitoring is an important guarantee for fetal health and early treatment. Fetal movement is one of critical indicators of fetal monitoring, which plays an important role in fetal health. Counting the number of fetal movement by pregnant women is a traditional method for long-term monitoring. However, there are many defects in pregnant women’s feeling count, which cannot meet the accurate requirements of modern perinatal medicine. With the rapid development of biological and electronic technology, various sensors are used to probe the fetal dynamic monitoring, but not on fetal movement. This research proposes a monitoring method for fetal movement via three electrodes. Briefly: first, three electrodes are used to extract electrical signals in the abdomen of pregnant women;second, these signals are amplified and filtered;third, A/D converter with microprocessor is used to make analog digital conversion, which can be stored in the SD card under the control of the microprocessor;finally, the SD card data are processed by computer software and the fetal movement information is analyzed.

HSP47 Deletion Inhibits TGF-β1 Stimulation on Proliferation and Collagen Synthesis of Human Tenon Fibroblasts

Heat shock protein 47 (HSP47) is a collagen-specific molecular chaperone that is required for mo-lecular maturation of various types of collagens. Many studies have shown a close association be-tween increased expression of HSP47 and excessive accumulation of collagens in scar tissues of various human fibrotic diseases. However, the role of HSP47 in formation of scar after glaucoma filtration surgery is still unclear. In this study, we deleted the expression of HSP47 in human tent on fibroblasts (HTFs) by virus infection, and then the proliferation and collagen synthesis were compared between HSP47 deletion cells and control upon TGF-β1 stimulation. Our data showed that HSP47 deletion could significantly inhibit the proliferation and collagen synthesis of HTFs upon TGF-β1 stimulation, HSP47 gene suppression might be a novel method to against the formation of scar after glaucoma surgery.