97 research outputs found

    Rutin-functionalized multi-walled carbon nanotubes: molecular docking, physicochemistry and cytotoxicity in fibroblasts

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    Multi-Walled Carbon Nanotubes (MWCNT) have been functionalized with rutin through three steps (i. reaction step; ii. purification step; iii. drying step) and their physicochemical properties investigated with respect to morphological structure, thermal analysis, Fourier Transform Infrared Spectroscopy (FTIR), and cytotoxicity. The molecular docking suggested the rutin-functionalized MWCNT occurred by hydrogen bonds, which was confirmed by FTIR assays, corroborating the results obtained by thermal analyses. A tubular shape, arranged in a three-dimensional structure, could be observed. Mild cytotoxicity observed in 3T3 fibroblasts suggested a doseeffect relationship after exposure. These findings suggest the formation of aggregates of filamentous structures on the cells favoring the cell penetration.The authors acknowledge Classius Ferreira da Silva, from the Instituto de Ciências Ambientais, Químicas e Farmacêuticas, Universidade Federal de São Paulo, for the scanning electron microscopy analyses.info:eu-repo/semantics/publishedVersio

    Microbiota of Vibrio sp. in the hepatopancreas of cultured white pacific shrimp (Litopenaeus vannamei)

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    ABSTRACT Objective. The present study aimed to investigate the presence of vibrios in the hepatopancreas of cultured shrimp. Materials and methods. Vibrios from the hepatopancreas of fifteen samples of five specimens each, of apparently healthy Pacific white shrimp (Litopenaeus vannamei) were isolated, identified and quantified. Results. The vibrio density ranged from 430 to 2,400 MPN g-1 (rs MPN cm-1=-0.114; rs MPN g-1 = 0.211). Thirty isolations were obtained, most of which belonged to the species V. cholerae (n=11) and V. parahaemolyticus (n=7). Conclusions. The outcomes of the present study suggest that, even in the absence of symptoms of vibriosis, the microbiota of the hepatopancreas of cultured shrimp may include sucrose positive and negative vibrios

    Development of a manometric monitoring method for early detection of air microbiological contamination in the bloodstream

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    Atmospheric air is a microbial habitat of pathogenic bioaerosols that may pose serious risks to humans. A commonly laboratory-based approach for the diagnosis of such infections in the bloodstream is the blood culture analysis. Its clinical relevance is attributed to the fact that these infections are characterized by high rates of morbidity and mortality, requiring the need for efficient methods for rapid diagnosis. For this reason, our study aimed to develop a method of manometric monitoring for the rapid detection of viable microorganisms in blood culture vials. A methodology was developed to detect pressure variation in intra-vials through a manometric instrument that was coupled to vials of blood culture containing culture broth that allowed microbial growth. This device allowed the early detection of microbial activity based on the production or use of intra-flask gases as a result of microbial metabolic activity. The analyzed variables were the pressure as a function of time, microbial species, and culture medium. The highest pressure found in the flasks without microorganisms was 40 mmHg between 2 and 6 h, and the lowest pressure was 42 mmHg between 21 and 24 h. The variation of the internal pressure in blood culture flasks according to different groups of microorganisms as a function of time demonstrated that the fermentative gram-negative bacilli and gram-positive cocci exhibited a significant increase in relation to their respective control groups (p < 0.001). The non-fermenting gram-negative bacilli showed expected results in relation to the pressure variation in which the production of negative pressures was noticed during the period of analysis, with a significant difference with respect to their control groups (p < 0.001). The developed methodology for the early detection of microorganisms responsible for bloodstream infection was demonstrated to be effective.e Fundação de Apoio à Pesquisa e à Inovação Tecnológica do Estado de Sergipe-Program Centelha (FAPITEC/SE) and by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES), and Portuguese Science and Technology Foundation (FCT) through the project UIDB/04469/2020 (strategic fund) funded by national funds, and co-financed Education (FCT/MEC) from national funds and FEDER, under the Partnership Agreement PT2020info:eu-repo/semantics/publishedVersio

    The term basal plate of the human placenta as a source of functional extravillous trophoblast cells

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    Background\ud Extravillous trophoblast (EVT) cells are of pivotal importance in human embryo implantation and homeostasis of the maternal fetal interface. Invasion of the endometrium by EVT contributes to placental anchorage, spiral artery remodeling, immunological defense, tolerogenic responses, and several collaborative cross talks involved in establishing and maintaining a successful pregnancy. We report here an improved protocol for the isolation of fully differentiated EVT cells from the basal plate of the human term placenta.\ud \ud \ud Methods\ud The basal plate was carefully dissected from the villous tissue and the amniochorion membrane prior to enzymatic digestion. Term basal EVT cells were isolated using a 30 and 60% Percoll gradient. A panel of markers and characteristics of the isolated cells were used to confirm the specificity and efficiency of the method so that their potential as an investigative tool for placental research could be ascertained.\ud \ud \ud Results\ud Isolated cells were immunoreactive for cytokeratin-7 (CK-7), placental growth factor, placental alkaline phosphatase, human leukocyte antigen G1 (HLA-G1), and α1 and α5 integrins, similarly to the EVT markers from first trimester placental villi. Around 95% of the isolated cells labeled positively for CK-7 and 82% for HLA-G1. No significant change in viability was observed during 48 h of EVT culture as indicated by propidium iodide incorporation and trypan blue test exclusion. Genes for metalloproteinases MMP-2 and MMP9 (positive regulators of trophoblast invasiveness) were expressed up to 48 h of culturing, as also the gelatinolytic activity of the isolated cells. Transforming growth factor (TGF)-beta, which inhibits proliferation, migration, and invasiveness of first-trimester EVT cells, also reduced invasion of isolated term EVT cells in transwell assays, whereas epidermal growth factor was a positive modulator.\ud \ud \ud Conclusions\ud Term basal plate may be a viable source of functional EVT cells that is an alternative to villous explant-derived EVT cells and cell lines. Isolated term EVT cells may be particularly useful in investigation of the role of trophoblast cells in pathological gestations, in which the precise regulation and interactive ability of extravillous trophoblast has been impaired.Fundação de Amparo à Pesquisa do Estado de São Paulo [2009/05354-0; 2013/12243-5]Conselho Nacional de Desenvolvimento Científico e Tecnológico [40088/2010-5]Coordenação de Aperfeiçoamento de Pessoal de Nível Superior [4178-11-4]Austrian Science Funds [P-22687-B13

    Surveillance of active human cytomegalovirus infection in hematopoietic stem cell transplantation (HLA sibling identical donor): search for optimal cutoff value by real-time PCR

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    <p>Abstract</p> <p>Background</p> <p>Human cytomegalovirus (CMV) infection still causes significant morbidity and mortality after allogeneic hematopoietic stem cell transplantation (HSCT). Therefore, it is extremely important to diagnosis and monitor active CMV infection in HSCT patients, defining the CMV DNA levels of virus replication that warrant intervention with antiviral agents in order to accurately prevent CMV disease and further related complications.</p> <p>Methods</p> <p>During the first 150 days after allogeneic HSTC, thirty patients were monitored weekly for active CMV infection by <it>pp65 </it>antigenemia, nested-PCR and real-time PCR assays. Receiver operating characteristic (ROC) plot analysis was performed to determine a threshold value of the CMV DNA load by real-time PCR.</p> <p>Results</p> <p>Using ROC curves, the optimal cutoff value by real-time PCR was 418.4 copies/10<sup>4 </sup>PBL (sensitivity, 71.4%; specificity, 89.7%). Twenty seven (90%) of the 30 analyzed patients had active CMV infection and two (6.7%) developed CMV disease. Eleven (40.7%) of these 27 patients had acute GVHD, 18 (66.7%) had opportunistic infection, 5 (18.5%) had chronic rejection and 11 (40.7%) died - one died of CMV disease associated with GVHD and bacterial infection.</p> <p>Conclusions</p> <p>The low incidence of CMV disease in HSCT recipients in our study attests to the efficacy of CMV surveillance based on clinical routine assay. The quantification of CMV DNA load using real-time PCR appears to be applicable to the clinical practice and an optimal cutoff value for guiding timely preemptive therapy should be clinically validated in future studies.</p

    Proteasome inhibition and ROS generation by 4-nerolidylcatechol induces melanoma cell death

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    Induction of apoptotic cell death in response to chemotherapy and other external stimuli has proved extremely difficult in melanoma, leading to tumor progression, metastasis formation and resistance to therapy. A promising approach for cancer chemotherapy is the inhibition of proteasomal activity, as the half-life of the majority of cellular proteins is under proteasomal control and inhibitors have been shown to induce cell death programs in a wide variety of tumor cell types. 4-Nerolidylcatechol (4-NC) is a potent antioxidant whose cytotoxic potential has already been demonstrated in melanoma tumor cell lines. Furthermore, 4-NC was able to induce the accumulation of ubiquitinated proteins, including classic targets of this process such as Mcl-1. As shown for other proteasomal inhibitors in melanoma, the cytotoxic action of 4-NC is time-dependent upon the pro-apoptotic protein Noxa, which is able to bind and neutralize Mcl-1. We demonstrate the role of 4-NC as a potent inducer of ROS and p53. The use of an artificial skin model containing melanoma also provided evidence that 4-NC prevented melanoma proliferation in a 3D model that more closely resembles normal human skin.FAPESP [2006/50479-7, 2006/60930-8, 2008/58817-4, 2009/54816-6 2010/50157-5]FAPESPCNPqCNPqINCT_if (CNPq)INCT-if CNPqCAPESCAPESPRP-USPPRPUS
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