Photocatalytic antibacterial effects on TiO2-anatase upon UV-A and UV-A/VIS threshold irradiation

Anatas ist ein bekanntes fotokatalytisches Material, in dem aktive Sauerstoffspezies unter UV-Einstrahlung generiert werden können und die angehafteten organischen Moleküle können über eine Reihe von Oxidierungsprozessen zerlegt werden. Die Hauptaufgabe dieser Studie war es, zu untersuchen, ob ausreichend fotokatalytische antibakterielle Aktivitäten auf Anatas vorhanden sind, wenn die Wellenlänge der Einstrahlung zur sichtbaren Lichtregion verschoben wird. Das Mikrowaagengerät mit Quarzkristallen (QCM-D; D-300, Q-Sense, Schweden) wurde in diesem Test verwendet und es besteht aus 3 Hauptteilen: einer Elektronikeinheit zur Überwachung der experimentellen Bedingungen, einer Durchflusszelle für das Laden der akustischen Sensoren und der Q-Sense Software zur Aufzeichnung der Frequenz (f) und der Dissipationssignale (D) der Quarzschwingung. In dieser Studie, nach der angeschlossenen Ablage von Speichelpellikel und der Streptococcus gordonii (S. Gordonii) auf der Sensoroberfläche von Anatas, wurden verschiedene Einstrahlungsprotokolle (UV-A > 320 nm; UV-A/VIS > 380 nm, > 390 nm; VIS 400 – 410 nm) verwendet, um eine Fotokatalyse anzuregen. Außerdem wurde der Durchfluss während der Einstrahlungsperiode zwischen einem höheren (2700 µl min-1) und einem regulären (110 µl min-1) Wert angepasst. Zwei Referenztests wurden entworfen, um den jeweiligen Einfluss der Einstrahlung und der Scherrate auf den antibakteriellen Effekt zu untersuchen. Zusätzlich wurden Referenztests auf Quarzkristalle mit Ti-Beschichtung unter UV-A-Einstrahlung und einem höheren Durchfluss (2700 µl min-1) durchgeführt, um zu bestimmen, ob antibakterielle Effekte nur auf die fotokatalytische Aktivität beschränkt sind, oder ob sie auch direkt während der UV-A auftreten. Nach der Bestrahlung wurden die Quarzkristalle abgebaut und die angehafteten Bakterien wurden mit dem bakteriellen Viabilitätsbausatz LIVE/DEAD® BacLightTM eingefärbt. Die fluoreszenten Färbeergebnisse auf den Oberflächen des Quarzkristalls wurden mikroskopisch analysiert und von einer Spiegel-Reflex-Kamera dokumentiert. Der Anteil der toten Bakterien auf den Oberflächen wurde für jede Gruppe durch Bildbearbeitung kalkuliert. Als Ergebnis dessen konnte man, unter UV-A (> 320 nm) und UV-A/VIS (> 380 nm) Einstrahlung und einer fotokatalytischen antibakteriellen Performance, bakterientötende Effekte und verminderte Zahlen von angehefteten Bakterien feststellen. Wenn allerdings die Wellenlänge der Einstrahlung auf > 390 nm beschränkt war, konnte keine signifikante antibakterielle Performance festgestellt werden. Der fotokatalytische antibakterielle Effekt konnte der besonderen Eigenschaft von Anatas zugeteilt werden. Da das UVA-A/VIS-Licht im Bereich zwischen 380 und 390 nm – es wurde herausgefunden, dass es Bakterien angreift, ähnlich wie UV-A – in klinischen Anwendungen wesentlich akzeptable ist, als das potenziell schädliche und energischere UV-A-Licht, besteht ein erhebliches Interesse, fotokatalytische antibakterielle Effekte in diesem Wellenbereich weiter zu untersuchen, um klinisch akzeptable Behandlungsprotokolle zu entwickeln

Induced Susceptibility of Host Is Associated with an Impaired Antioxidant System Following Infection with Cryptosporidium parvum in Se-Deficient Mice

BACKGROUND: Susceptibility or resistance to infection with Cryptosporidium parvum (C.parvum) correlates with Selenium (Se) deficiency in response to infection. Both adult Se-adequate and Se-deficient mouse models of cryptosporidiosis were used to study the cell-mediated immune response during the course of C. parvum infection. METHODOLOGY/PRINCIPAL FINDINGS: Blood samples from mouse models were used for Se status. The concentration of MDA, SOD, GPx and CAT in blood has revealed that lower Se level exist in Se-deficient mice. Mesenteric lymph node (MLN) lymphocytes from both mouse models were proliferated after ex vivo re-stimulation with C. parvum sporozoite antigen. The study of the cytokine profiles from the supernatant of proliferated MLN cells revealed that Se-adequate mice produced higher levels of Th1 (IFN-gamma and IL-2) and moderate amounts of Th2 (IL-4) cytokines throughout the course of infection. Whereas, MLN cells from Se-deficient mice produced lower levels of IFN-gamma, IL-2 and IL-4 cytokines. The counts of total white cell and CD3, CD4, CD8 cell in Se-adequate were higher than that in Se-deficient mice. SIGNIFICANCE: These results suggest that Cell immunity is affected by Se status after infection with C. parvum from kinetic changes of different white cells and cytokine. In conclusion, induced susceptibility of host is associated with an impaired antioxidant system following infection with C. parvum in C57BL/6 Selenium deficient mice

CCL3 and CCL20-recruited dendritic cells modified by melanoma antigen gene-1 induce anti-tumor immunity against gastric cancer ex vivo and in vivo

<p>Abstract</p> <p>Background</p> <p>To investigate whether dendritic cell (DC) precursors, recruited by injection of <b>chemokine ligand 3 (CCL3) and CCL20</b>, induce anti-tumor immunity against gastric cancer induced by a DC vaccine expressing melanoma antigen gene-1 (MAGE-1) ex vivo and in vivo.</p> <p>Methods</p> <p>B6 mice were injected with CCL3 and CCL20 via the tail vein. Freshly isolated F4/80^-B220^-CD11c⁺cells cultured with cytokines were analyzed by phenotype analysis and mixed lymphocyte reaction (MLR). For adenoviral (Ad)-mediated gene transduction, cultured F4/80^-B220^-CD11c⁺cells were incubated with Ad-MAGE-1. Vaccination of stimulated DC induced T lymphocytes. The killing effect of these T cells against gastric carcinoma cells was assayed by MTT. INF-γ production was determined with an INF-γ ELISA kit. In the solid tumor and metastases model, DC-based vaccines were used for immunization after challenge with MFC cells. <b>Tumor size, survival of mice, and number of pulmonary metastatic foci were used to assess the therapeutic effect of DC vaccines</b>.</p> <p>Results</p> <p>F4/80^-B220^-CD11c⁺cell numbers increased after <b>CCL3 and CCL20 </b>injection. Freshly isolated F4/80^-B220^-CD11c⁺cells cultured with cytokines were phenotyically identical to typical DC and gained the capacity to stimulate allogeneic T cells. These DCs were transduced with Ad-MAGE-1, which were prepared for DC vaccines expressing tumor antigen. T lymphocytes stimulated by DCs transduced with Ad-MAGE-1 exhibited specific killing effects on gastric carcinoma cells and produced high levels of INF-γ ex vivo. In vivo, tumor sizes of the experimental group were much smaller than both the positive control group and the negative control groups (<it>P </it>< 0.05). Kaplan-Meier survival curves showed that survival of the experimental group mice was significantly longer than the control groups (<it>P </it>< 0.05). In addition, MAGE-1-transduced DCs were also a therapeutic benefit on an established metastatic tumor, resulting in a tremendous decrease in the number of pulmonary metastatic foci.</p> <p>Conclusions</p> <p><b>CCL3 and CCL20</b>-recruited DCs modified by adenovirus-trasnsduced, tumor-associated antigen, MAGE-1, can stimulate anti-tumor immunity specific to gastric cancer ex vivo and in vivo. This system may prove to be an efficient strategy for anti-tumor immunotherapy.</p

New Fast Fall Detection Method Based on Spatio-Temporal Context Tracking of Head by Using Depth Images

© 2015 by the authors; licensee MDPI, Basel, Switzerland. In order to deal with the problem of projection occurring in fall detection with two-dimensional (2D) grey or color images, this paper proposed a robust fall detection method based on spatio-temporal context tracking over three-dimensional (3D) depth images that are captured by the Kinect sensor. In the pre-processing procedure, the parameters of the Single-Gauss-Model (SGM) are estimated and the coefficients of the floor plane equation are extracted from the background images. Once human subject appears in the scene, the silhouette is extracted by SGM and the foreground coefficient of ellipses is used to determine the head position. The dense spatio-temporal context (STC) algorithm is then applied to track the head position and the distance from the head to floor plane is calculated in every following frame of the depth image. When the distance is lower than an adaptive threshold, the centroid height of the human will be used as the second judgment criteria to decide whether a fall incident happened. Lastly, four groups of experiments with different falling directions are performed. Experimental results show that the proposed method can detect fall incidents that occurred in different orientations, and they only need a low computation complexity

Clinicopathologic Significance of HIF-1α, CXCR4, and VEGF Expression in Colon Cancer

We investigated the clinicopathologic significance of HIF-1, CXCR4, and VEGF expression using immumohistochemistry in human colon cancer. HIF-1, CXCR4, and VEGF high expression levels were correlated positively with TNM stage, lymph node involvement, and distant metastasis Furthermore, we found that combined high expression of any two of the three molecules (P = .028 for HIF-1/CXCR4, P = .007 for HIF-1/VEGF, and P = .004 for CXCR4/VEGF) had stronger correlation with lymph node metastasis than did each alone. However, a relationship with distant metastasis is seen only with the combinations CXCR4/VEGF (P = .069 for HIF-1/CXCR4, P = .062 for HIF-1/VEGF, and P = .035 for CXCR4/VEGF) as compared with those of single molecule high expression alone. Combined expression of all three molecules strongly correlates with lymph node metastasis and distant metastasis. The mRNA expression of HIF-1, CXCR4, and VEGF were quantified by real-time PCR in different colon cancer tissue samples, the experiment results shown that fresh colon tissue samples significantly overexpressed CXCR4 and VEGF mRNA compared with negative control. Therefore, the disease-free survival of all patients after curative resection can be considered in association with all three markers expression

Parasite Species Associated With Wild Plateau Pika (Ochotona Curzoniae) In Southeastern Qinghai Province, China

A survey was conducted to determine the prevalence and seasonal abundance of egg, larval, and adult stages of helminths; oocyts of protozoans; and ectoparasites of plateau pikas (Ochotona curzoniae) in seven areas of southeastern Qinghai Province, China, during August 2006 and May 2007. Fecal samples collected from 430 plateau pikas were examined by the modified McMaster technique, which revealed that 83% of the samples contained eggs from two or more helminth species. Mean fecal egg counts were generally moderate and showed the same trend irrespective of the age or sex of the pikas. The prevalence and counts of cestode eggs showed strong seasonal relationships that corresponded with the rainfall pattern in the study area during the study period. Of the 430 plateau pika examined at necropsy, 89% contained adult nematode or cestode species, but none of these contained adult trematode species or protozoans. Overall, six genera of adult nematodes including Oesophagostomum sp., Cephaluris coloradensis, Eugenuris schumakowiescsi, Haemonchus sp., Trichuris sp., and Chbertiinae sp.; three genera of adult cestodes including Schizorchis sp., Ochotonae sp., and Hymenolepis nana; three ectoparasite species including Hypoderma curzonial, Pulex sp., and Ixodes ovatus; and one proscolex stage of a cestode, Echinococcus multilocularis or Echinococcus shiquicus, were encountered during the study. Other genera examined occurred in low numbers, which did not allow any meaningful comparisons. Overall, results suggest that four parasite species, Hypoderma curzonial, Pulex sp., Ixodes ovatus Neumann, and Cephaluris coloradensis, may be regulating factors in controlling future numbers of plateau pika in this study area. These data provide evidence of a natural biologic control mechanism of plateau pika on grassland habitats, and may be of use for identifying the mechanism of transmission of parasites between plateau pika, livestock, and humans

Impacts of global climate change on birds and marine mammals in Antarctica

Birds and marine mammals in Antarctica, especially penguins and seals, are top consumers and critical elements of the Southern Ocean ecosystem. As a region undergoing rapid global change, new challenges will be posed to the survival of these vertebrates species. Global climate change causes many alterations, such as ocean temperature rise, altered sea ice distribution, and abnormal climate events along with effects of intensive human activities, such as fishing. These not only directly affect the spatiotemporal distributions and population dynamics of Antarctic birds and marine mammals but also indirectly influence them via modification of their food resources. At present, the impact of climate change on birds and marine mammals in the Antarctica is focusing on a number of species in a few areas. Response mechanisms of these species are still very limited and therefore require further long-term and continuous monitoring and research

Alteration of CXCR7 Expression Mediated by TLR4 Promotes Tumor Cell Proliferation and Migration in Human Colorectal Carcinoma

The link between inflammation and colorectal carcinoma has been acknowledged. However, the impact of bacterial lipopolysaccharide (LPS) binding to Toll-like receptor 4 (TLR4) on chemokine receptors in human colorectal carcinoma cells still remains to be elucidated. The present study shows that exposure to LPS elevated CXC chemokine receptor 7 (CXCR7) expression in colorectal carcinoma SW480 and Colo 205 cell lines expressing TLR4/myeloid differential protein (MD-2). CXCR7 is associated with SW480 cell proliferation and migration. However, exposure of SW480 and Colo 205 cells to LPS had no effect on CXCR4 expression. To further support the above results, the expression of TLR4, MD-2, and CXCR7 was analyzed in human colorectal carcinoma tissues. Higher rates of TLR4 (53%), MD-2 (70%), and CXCR7 (29%) expression were found in colorectal carcinoma tissues than in normal tissues. We demonstrated that the recombination of TLR4, MD-2 and CXCR7 strongly correlated with tumor size, lymph node metastasis and distant metastasis in colorectal carcinoma tissue samples (p = 0.037, p = 0.002, p = 0.042, resp.). Accordingly, simultaneous examination of the expression of TLR4, MD-2 and CXCR7 in cancer tissues of colorectal carcinoma may provide valuable prognostic diagnosis of carcinoma growth and metastasis. Interplay of TLR4, MD-2 and CXCR7 may be of interest in the context of novel immunomodulatory therapies for colorectal carcinoma

Dissection of the mechanism of traditional Chinese medical prescription-Yiqihuoxue formula as an effective anti-fibrotic treatment for systemic sclerosis

BACKGROUND: Systemic sclerosis (SSc) is a connective tissue fibrotic disease for which there is no effective treatment. Traditional Chinese Medicine (TCM), such as the Yiqihuoxue formula used in Shanghai TCM-integrated Hospital, has shown the efficacy of anti-fibrosis in clinical applications. This study was aiming to dissect the anti-fibrotic mechanism of Yiqihuoxue treatment for SSc. METHODS: Bleomycin-induced mice and SSc dermal fibroblasts were treated with Yiqihuoxue decoction; NIH-3T3 fibroblasts were exposed to exogenous TGF-β1, and then cultured with or without Yiqihuoxue decoction. Luciferase reporter gene assay was used to determine the activity of Smad binding element (SBE). Quantitative reverse transcription-polymerase chain reaction (RT-PCR) was used to examine the mRNA levels of extracellular matrix (ECM) genes. The protein levels of type I collagen, Smad3 and phosphorylated-Smad3 (p-Smad3) were detected by western blotting. Student’s t-tests were used to determine the significance of the results. RESULTS: Bleomycin-induced mice, SSc dermal fibroblasts and TGF-β1-induced NIH/3T3 fibroblasts showed higher levels of ECM gene transcriptions and collagen production. In addition, the phosphorylation level of Smad3 and activity of SBE were significantly increased after exogenous TGF-β1 induction. Whereas, Yiqihuoxue treatment could obviously attenuate fibrosis in bleomycin-induced mice, down regulate ECM gene expressions and collagen production in SSc dermal fibroblasts and TGF-β1-induced NIH/3T3 fibroblasts. Furthermore, the aberrantly high phosphorylation level of Smad3 and activity of SBE in the TGF-β1-induced NIH/3T3 fibroblasts were also dramatically decreased by Yiqihuoxue treatment. CONCLUSIONS: Yiqihuoxue treatment could effectively reduce collagen production via down-regulating the phosphorylation of Smad3 and then the activity of SBE, which are involved in the TGF-β pathway and constitutively activated in the progression of SSc