Xyloglucan and Concanavalin A based dressings in the topical treatment of mice wound healing process

For medical biomaterials, xyloglucan dispersions can form films or gels to be applied as a wound dressing. For this purpose, the structural characterization of xyloglucan dressing (XG) and xyloglucan dressing containing 0.5 mg/mL of concanavalin A (XGL) was performed. The lectin release capacity and stability, cytotoxicity, and pro-wound healing effects were also investigated. XG and XGL films were prepared by mixing 0.5 % (w/v) xyloglucan with 0.3 % (v/v) glycerol. The ConA incorporated in the xyloglucan dressing maintained its biological activity for fourteen days in a controlled-release manner. The films were non-toxic, homogeneous, flexible, and accelerated the wound contraction compared with the control group, promoting less infiltration of inflammatory cells, angiogenesis, remodeling, and early epithelization. The films also alleviate the inflammation phase by reducing the production of pro-inflammatory cytokines (IFN-, TNF-, IL-1, IL-6, and IL-12), especially the XGL film, which promoted the up- and down-regulation of important proteins associated with the wound repair. All these findings suggest that XG and XGL films may represent a good therapeutic approach for wound healing applications.The authors are grateful for the financial support for research grants from the Conselho Nacional de Desenvolvimento Científico e Tecnol ´ogico (CNPq), Coordenaç˜ao de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) and the Fundaç˜ao de Amparo `a Ciˆencia e Tecnologia do Estado de Pernambuco (FACEPE). We are grateful to the Centro de Tecnologias Estrat´egicas do Nordeste (CETENE) and to the Laborat´orio de Imunopatologia Keizo Asami-LIKA at the Universidade Federal de Pernambuco (UFPE) for access to its installation and technical assistance.info:eu-repo/semantics/publishedVersio

Geographical distribution of American cutaneous leishmaniasis and its phlebotomine vectors (Diptera: Psychodidae) in the state of São Paulo, Brazil

<p>Abstract</p> <p>Background</p> <p>American cutaneous leishmaniasis (ACL) is a re-emerging disease in the state of São Paulo, Brazil. It is important to understand both the vector and disease distribution to help design control strategies. As an initial step in applying geographic information systems (GIS) and remote sensing (RS) tools to map disease-risk, the objectives of the present work were to: (i) produce a single database of species distributions of the sand fly vectors in the state of São Paulo, (ii) create combined distributional maps of both the incidence of ACL and its sand fly vectors, and (iii) thereby provide individual municipalities with a source of reference material for work carried out in their area.</p> <p>Results</p> <p>A database containing 910 individual records of sand fly occurrence in the state of São Paulo, from 37 different sources, was compiled. These records date from between 1943 to 2009, and describe the presence of at least one of the six incriminated or suspected sand fly vector species in 183/645 (28.4%) municipalities. For the remaining 462 (71.6%) municipalities, we were unable to locate records of any of the six incriminated or suspected sand fly vector species (<it>Nyssomyia intermedia</it>, <it>N. neivai</it>, <it>N. whitmani</it>, <it>Pintomyia fischeri</it>, <it>P. pessoai </it>and <it>Migonemyia migonei</it>). The distribution of each of the six incriminated or suspected vector species of ACL in the state of São Paulo were individually mapped and overlaid on the incidence of ACL for the period 1993 to 1995 and 1998 to 2007. Overall, the maps reveal that the six sand fly vector species analyzed have unique and heterogeneous, although often overlapping, distributions. Several sand fly species - <it>Nyssomyia intermedia </it>and <it>N. neivai </it>- are highly localized, while the other sand fly species - <it>N. whitmani, M. migonei, P. fischeri </it>and <it>P. pessoai </it>- are much more broadly distributed. ACL has been reported in 160/183 (87.4%) of the municipalities with records for at least one of the six incriminated or suspected sand fly vector species, while there are no records of any of these sand fly species in 318/478 (66.5%) municipalities with ACL.</p> <p>Conclusions</p> <p>The maps produced in this work provide basic data on the distribution of the six incriminated or suspected sand fly vectors of ACL in the state of São Paulo, and highlight the complex and geographically heterogeneous pattern of ACL transmission in the region. Further studies are required to clarify the role of each of the six suspected sand fly vector species in different regions of the state of São Paulo, especially in the majority of municipalities where ACL is present but sand fly vectors have not yet been identified.</p

Heme-Oxygenases during Erythropoiesis in K562 and Human Bone Marrow Cells

In mammalian cells, heme can be degraded by heme-oxygenases (HO). Heme-oxygenase 1 (HO-1) is known to be the heme inducible isoform, whereas heme-oxygenase 2 (HO-2) is the constitutive enzyme. Here we investigated the presence of HO during erythroid differentiation in human bone marrow erythroid precursors and K562 cells. HO-1 mRNA and protein expression levels were below limits of detection in K562 cells. Moreover, heme was unable to induce HO-1, at the protein and mRNA profiles. Surprisingly, HO-2 expression was inhibited upon incubation with heme. To evaluate the physiological relevance of these findings, we analyzed HO expression during normal erythropoiesis in human bone marrow. Erythroid precursors were characterized by lack of significant expression of HO-1 and by progressive reduction of HO-2 during differentiation. FLVCR expression, a recently described heme exporter found in erythroid precursors, was also analyzed. Interestingly, the disruption in the HO detoxification system was accompanied by a transient induction of FLVCR. It will be interesting to verify if the inhibition of HO expression, that we found, is preventing a futile cycle of concomitant heme synthesis and catabolism. We believe that a significant feature of erythropoiesis could be the replacement of heme breakdown by heme exportation, as a mechanism to prevent heme toxicity