23 research outputs found
Bacteriostatic Substrate by Conductivity Method and Electric Spark Discharge Method Combined with Electrospinning for Silver Dressing
This study uses the conductivity method, Electric Spark Discharge Method, and the electrospinning technique to develop a better silver-based antibacterial agent. The preparation process is free of chemical substances and also conforms to the green energy-saving process. The silver iodide was prepared in an iodine agar medium by using the conductivity method. Multiple bacteriostasis experiments showed that the molds grew in the position with iodine of the culture medium after 6 days, as well as in the position with silver iodide after 10 days. The results prove that silver iodide has better bacteriostatic ability than povidone iodine. The nanosilver colloid was prepared in the PVA solution by using the Electric Spark Discharge Method. UV-Vis, Zetasizer, and SEM-EDX analyses proved that the PVA solution contained nanosilver colloid with good suspension stability. Finally, the electrospinning technique was used to spin the PVA solution with nanosilver colloid into the PVA nanofibrous membrane. According to UV-Vis analysis, the absorption peak of this nanofibrous membrane is about 415 nm, meaning this nanofibrous membrane contains nucleate nanosilver colloid, and is very suitable for antiseptic dressing
A Study of Antibioactivity of Nanosilver Colloid and Silver Ion Solution
The colloidal silver solution was successfully prepared in dielectric fluid by using electrical spark discharge (ESD) without any surfactants. It does not require the toxic chemical agents in the process, which may affect the effectiveness of nanosilver colloid as an antibacterial agent. Nanocolloidal silver produced by ESD is characterized as low cost, zero environmental pollution, continuous, and rapid mass production process. In order to test the effect of antibioactivity, nanosilver dough was tested; the silver nanofluid was prepared by ESD machine, made into dough at different concentrations, and fermented for three hours in order to observe changes in the diameter of the dough. The results showed that the effect of effectiveness of nanosilver at the concentration of 100 ppm was weak, whereas the effect of 60 ppm silver ion (100 ppm AgNO3) was significant, as the dissociation rate of silver ion concentration correlates to the antibioactivity
Türkiye Türkçesinde orta hece düşmesi /
At head of title: Atatürk Kültür, Dil ve Tarih Yüksek Kurumu.Includes bibliographical references (p. [245]-248) and indexes.Yunus Emre InstituutYunus Emre Instituu
Mapping the CP-Transgene Insert in the Papaya Genome and Developing a Hermaphrodite Transgenic Hybrid with Broad-Spectrum Resistance to Papaya Ringspot Virus
Papaya ringspot virus (PRSV) limits papaya production worldwide. Previously, we generated transgenic lines of hybrid Tainung No.2 (TN-2) carrying the coat protein (CP) gene of PRSV with broad resistance to PRSV strains. Unfortunately, all of them were female, unacceptable for growers and consumers in practical applications. With our reported flanking sequences and the newly released papaya genomic information, the CP-transgene insert was identified at a non-coding region in chromosome 3 of the papaya genome, and the flanking sequences were verified and extended. The female transgenic line 16-0-1 was first used for backcrossing with the parental Sunrise cultivar six times and then followed by selfing three times. With multi-level molecular markers developed from the PRSV CP transgene and the genomic flanking sequences, the presence and zygosity of the CP transgene were characterized at the seedling stage. Meanwhile, hermaphrodite genotype was identified by a sex-linked marker. With homozygotic transgene and horticultural properties of Sunrise, a selected hermaphrodite individual was propagated by tissue culture (TC) and used as maternal progenitor to cross with non-transgenic parental cultivar Thailand to generate a new hybrid cultivar TN-2 with a hemizygotic CP-transgene. Three selected hermaphrodite individuals of transgenic TN were micropropagated by TC, and they showed broad-spectrum resistance to different PRSV strains from Taiwan, Hawaii, Thailand, and Mexico under greenhouse conditions. The selected clone TN-2 #1, with excellent horticultural traits, also showed complete resistance to PRSV under field conditions. These selected TC clones of hermaphrodite transgenic TN-2 provide a novel cultivation system in Taiwan and elsewhere
Arsenic treatment increase Aurora-A overexpression through E2F1 activation in bladder cells
Abstract Background Arsenic is a widely distributed metalloid compound that has biphasic effects on cultured cells. In large doses, arsenic can be toxic enough to trigger cell death. In smaller amounts, non-toxic doses may promote cell proliferation and induces carcinogenesis. Aberration of chromosome is frequently detected in epithelial cells and lymphocytes of individuals from arsenic contaminated areas. Overexpression of Aurora-A, a mitotic kinase, results in chromosomal instability and cell transformation. We have reported that low concentration (≦1 μM) of arsenic treatment increases Aurora-A expression in immortalized bladder urothelial E7 cells. However, how arsenic induces carcinogenesis through Aurora-A activation remaining unclear. Methods Bromodeoxyuridine (BrdU) staining, MTT assay, and flow cytometry assay were conducted to determine cell proliferation. Messenger RNA and protein expression levels of Aurora-A were detected by reverse transcriptional-PCR and Western blotting, respectively. Centrosome of cells was observed by immunofluorescent staining. The transcription factor of Aurora-A was investigated by promoter activity, chromosome immunoprecipitation (ChIP), and small interfering RNA (shRNA) assays. Mouse model was utilized to confirm the relationship between arsenic and Aurora-A. Results We reveal that low dosage of arsenic treatment increased cell proliferation is associated with accumulated cell population at S phase. We also detected increased Aurora-A expression at mRNA and protein levels in immortalized bladder urothelial E7 cells exposed to low doses of arsenic. Arsenic-treated cells displayed increased multiple centrosome which is resulted from overexpressed Aurora-A. Furthermore, the transcription factor, E2F1, is responsible for Aurora-A overexpression after arsenic treatment. We further disclosed that Aurora-A expression and cell proliferation were increased in bladder and uterus tissues of the BALB/c mice after long-term arsenic (1 mg/L) exposure for 2 months. Conclusion We reveal that low dose of arsenic induced cell proliferation is through Aurora-A overexpression, which is transcriptionally regulated by E2F1 both in vitro and in vivo. Our findings disclose a new possibility that arsenic at low concentration activates Aurora-A to induce carcinogenesis
Non-planar bioprinting with molding assistance for irregular wound shape
Most human organs and tissues have different shapes, which vary per individual. When printing biomedical scaffolds using material extrusion-based additive manufacturing bioprinters, sacrificial layers are generally used to support the suspended parts of the scaffold. However, the in-process generation of sacrificial layers is time-consuming and the scaffold can be damaged when removing the sacrificial layers. In this study, a novel non-planar grid slicing (NPGS) process was proposed for printing irregularly shaped tissues with low aspect ratios (for example, skin wounds), where the required 3D shape is formed following the deposition of non-planar paths, layer-by-layer. By stacking layers of bioink onto a non-planar support base, the NPGS process considerably reduced the total length of the deposition paths and number of fragmented paths. Therefore, it can reduce the use of costly bioink and improve the success rate of the scaffold printing. The proposed NPGS process and traditional planar slicing (TPS) process were used to fabricate scaffolds that conform to the shape and depth of two clinical wounds. Compared to TPS, NPGS reduced the total length of the deposition paths and number of fragmented paths (paths shorter than 5Â mm) by 49.2% and 59.6%, respectively. In animal testing, a large irregular wound was created on the rat's dorsal skin and treated with tri-cell-laden hydrogel printed by the NPGS process, demonstrating full repair after 28 days. The NPGS process shows great potential for customized biofabrication in tissue engineering
Metabolic Control with Insulin Pump Therapy: Preliminary Experience
The benefits of insulin pump therapy on the metabolic control of both type 1 and type 2 diabetes have been reported. Such reports have prompted our interest to investigate the long-term metabolic effects of insulin pump therapy at our institution.
Methods: We retrospectively analyzed the management of type 1 and type 2 diabetic patients who began extended insulin pump therapy at Changhua Christian Hospital between November 2004 and October 2007. One-way ANOVA and post hoc analysis were used to compare baseline glycosylated hemoglobin (HbA1C) values with subsequent values.
Results: We studied 12 patients who were on continuous subcutaneous insulin infusion (CSII) therapy at the time of data collection. Mean duration of CSII therapy was 2.3 years. A reduction in HbA1C was found after administering CSII, which was sustained after 1, 2 and 3 years of therapy (7.0%, 6.7% and 6.6%, respectively), with statistical significance (p <0.05). No incidence of severe hypoglycemia or diabetic ketoacidosis occurred during the treatment period.
Conclusion: Our preliminary experience demonstrated the effectiveness of insulin pump therapy for both type 1 and type 2 diabetic patients. The reduction in their HbA1C values was both statistically and clinically significant. This treatment should be considered for patients poorly controlled by subcutaneous insulin injection therapy
Positive Programmed Cell Death-Ligand 1 Expression Predicts Poor Treatment Outcomes in Esophageal Squamous Cell Carcinoma Patients Receiving Neoadjuvant Chemoradiotherapy
Background: Programmed cell death-ligand 1 (PD-L1) is present in a subgroup of cancer patients who may be favorable targets for immune checkpoint inhibitor therapies. However, the significance of the PD-L1 expression in esophageal squamous cell carcinoma (ESCC) patients receiving neoadjuvant chemoradiotherapy remains unclear. Methods: By means of PD-L1 immunohistochemistry 22C3 pharmDx assay, we evaluate the PD-L1 expression and its association with clinical outcome in 107 ESCC patients receiving neoadjuvant chemoradiotherapy. Results: Patients with positive PD-L1 expression have significantly lower pathological complete response rates (13% versus 32%; p = 0.036) than those with negative PD-L1 expression. Univariate survival analysis found that positive PD-L1 expression were correlated with poor overall survival (p = 0.004) and inferior disease-free survival (p < 0.001). In a multivariate analysis, positive PD-L1 expression was independently associated with the absence of a pathologically complete response (p = 0.044, hazard ratio: 3.542), worse overall survival (p = 0.006, hazard ratio: 2.017), and inferior disease-free survival (p < 0.001, hazard ratio: 2.516). Conclusions: For patients with ESCC receiving neoadjuvant chemoradiotherapy, positive PD-L1 expression independently predicts the poor chemoradiotherapy response and worse treatment outcome. Thus, our data suggests that PD-L1 may be an influential biomarker for prognostic classification and for immune checkpoint inhibitor therapies in ESCC patients receiving neoadjuvant chemoradiotherapy