997 resultados para Pancreatic enzyme preparation


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This clinical study has investigated the antigenic activity of bacterial contents from exudates of acute apical abscesses (AAAs) and their paired root canal contents regarding the stimulation capacity by levels of interleukin (IL)-1 beta and tumor necrosis factor alpha (TNF-α) throughout the root canal treatment against macrophage cells. Paired samples of infected root canals and exudates of AAAs were collected from 10 subjects. Endodontic contents were sampled before (root canal sample [RCS] 1) and after chemomechanical preparation (RCS2) and after 30 days of intracanal medication with calcium hydroxide + chlorhexidine gel (Ca[OH]2 + CHX gel) (RCS3). Polymerase chain reaction (16S rDNA) was used for detection of the target bacteria, whereas limulus amebocyte lysate was used to measure endotoxin levels. Raw 264.7 macrophages were stimulated with AAA exudates from endodontic contents sampled in different moments of root canal treatment. Enzyme-linked immunosorbent assays were used to measure the levels of TNF-α and IL-1 beta. Parvimonas micra, Porphyromonas endodontalis, Dialister pneumosintes, and Prevotella nigrescens were the most frequently detected species. Higher levels of endotoxins were found in samples from periapical exudates at RCS1 (P < .005). In fact, samples collected from periapical exudates showed a higher stimulation capacity at RCS1 (P < .05). A positive correlation was found between endotoxins from exudates with IL-1 beta (r = 0.97) and TNF-α (r = 0.88) production (P < .01). The significant reduction of endotoxins and bacterial species achieved by chemomechanical procedures (RCS2) resulted in a lower capacity of root canal contents to stimulate the cells compared with that at RCS1 (P < .05). The use of Ca(OH)2 + CHX gel as an intracanal medication (RCS3) improved the removal of endotoxins and bacteria from infected root canals (P < .05) whose contents induced a lower stimulation capacity against macrophages cells at RCS1, RCS2, and RCS3 (P < .05). AAA exudates showed higher levels of endotoxins and showed a greater capacity of macrophage stimulation than the paired root canal samples. Moreover, the use of intracanal medication improved the removal of bacteria and endotoxins from infected root canals, which may have resulted in the reduction of the inflammatory potential of the root canal content.

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The basidiomycete fungus Gloeophyllum trabeum causes a typical brown rot and is known to use reactive oxygen species in the degradation of cellulose. The extracellular Cel12A is one of the few endo-1,4-β-glucanase produced by G. trabeum. Here we cloned cel12A and heterologously expressed it in Aspergillus niger. The identity of the resulting recombinant protein was confirmed by mass spectrometry. We used the purified GtCel12A to determine its substrate specificity and basic biochemical properties. The G. trabeum Cel12A showed highest activity on β-glucan, followed by lichenan, carboxymethylcellulose, phosphoric acid swollen cellulose, microcrystalline cellulose, and filter paper. The optimal pH and temperature for enzymatic activity were, respectively, 4.5 and 50 °C on β-glucan. Under these conditions specific activity was 239.2 ± 9.1 U mg(-1) and the half-life of the enzyme was 84.6 ± 3.5 hours. Thermofluor studies revealed that the enzyme was most thermal stable at pH 3. Using β-glucan as a substrate, the Km was 3.2 ± 0.5 mg mL(-1) and the Vmax was 0.41 ± 0.02 µmol min(-1). Analysis of the effects of GtCel12A on oat spelt and filter paper by scanning electron microscopy revealed the morphological changes taking place during the process.

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In this study, a novel concise series of molecules based on the structure of goniothalamin (1) was synthesized and evaluated against a highly metastatic human pancreatic cancer cell line (Panc-1). Among them, derivative 8 displayed a low IC50 value (2.7 μM) and its concentration for decreasing colony formation was 20-fold lower than goniothalamin (1). Both compounds reduced the levels of the receptor tyrosine kinase (AXL) and cyclin D1 which are known to be overexpressed in pancreatic cancer cells. Importantly, despite the fact that goniothalamin (1) and derivative 8 caused pancreatic cancer cell cycle arrest and cell death, only derivative 8 was able to downregulate pro-survival and proliferation pathways mediated by mitogen activated protein kinase ERK1/2. Another interesting finding was that Panc-1 cells treated with derivative 8 displayed a strong decrease in the transcription factor (c-Myc), hypoxia-inducible factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF) protein levels. Notably, the molecular effects caused by derivative 8 might not be related to ROS generation, since no significant production of ROS was observed in low concentrations of this compound (from 1.5 up to 3 μM). Therefore, the downregulation of important mediators of pancreatic cancer aggressiveness by derivative 8 reveals its great potential for the development of new chemotherapeutic agents for pancreatic cancer treatment.

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Preparation of protective coating possessing antimicrobial properties is present day need as they increase the shelf life of fruits and vegetables. In the present study, preparation of agar-silver nanoparticle film for increasing the shelf life of fruits is reported. Silver nanoparticles (Ag-NPs) biosynthesised using an extract of Ocimum sanctum leaves, were mixed with agar-agar to prepare an agar-silver nanoparticles (A-AgNp) film. This film was surface-coated over the fruits, Citrus aurantifolium (Thornless lime) and Pyrus malus (Apple), and evaluated for the determination of antimicrobial activity of A-AgNp films using disc diffusion method, weight loss and shelf life of fruits. This study demonstrates that these A-AgNp films possess antimicrobial activity and also increase the shelf life of fruits.

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Gellan microgels with potential application in delivery systems were obtained by physically cross-linked gellan gum. The microgels were produced by atomization followed by ionotropic gelation using CaCl2 (gellan/Ca) or KCl (gellan/K) as hardening agent and part of them were coated with chitosan in order to improve their resistance to gastric digestion. Size distribution, morphology and zeta potential of microgels were evaluated before and after in vitro digestion process. The long term stability was also evaluated. Spherical microparticles were obtained at gellan concentration above 0.6% w/w, showing average size among 70-120 μm. Most of the coated and uncoated microgels showed stability in aqueous media, except the uncoated gellan/K microgel. The in vitro digestion evaluation showed that all particles maintained their size and shape after the gastric digestion step. However, the enteric digestion caused disintegration of microgels indicating their potential application for enteric delivery systems. The chitosan-coated microgels showed lower degree of fragmentation when compared to the uncoated microgels, indicating that the coating process enable a better control of microgels releasing properties during the enteric digestion.

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Type 1 diabetes (T1D) is provoked by an autoimmune assault against pancreatic β cells. Exercise training enhances β-cell mass in T1D. Here, we investigated how exercise signals β cells in T1D condition. For this, we used several approaches. Wild-type and IL-6 knockout (KO) C57BL/6 mice were exercised. Afterward, islets from control and trained mice were exposed to inflammatory cytokines (IL-1β plus IFN-γ). Islets from control mice and β-cell lines (INS-1E and MIN6) were incubated with serum from control or trained mice or medium obtained from 5-aminoimidazole-4 carboxamide1-β-d-ribofuranoside (AICAR)-treated C2C12 skeletal muscle cells. Subsequently, islets and β cells were exposed to IL-1β plus IFN-γ. Proteins were assessed by immunoblotting, apoptosis was determined by DNA-binding dye propidium iodide fluorescence, and NO(•) was estimated by nitrite. Exercise reduced 25, 75, and 50% of the IL-1β plus IFN-γ-induced iNOS, nitrite, and cleaved caspase-3 content, respectively, in pancreatic islets. Serum from trained mice and medium from AICAR-treated C2C12 cells reduced β-cell death, induced by IL-1β plus IFN-γ treatment, in 15 and 38%, respectively. This effect was lost in samples treated with IL-6 inhibitor or with serum from exercised IL-6 KO mice. In conclusion, muscle contraction signals β-cell survival in T1D through IL-6.-Paula, F. M. M., Leite, N. C., Vanzela, E. C., Kurauti, M. A., Freitas-Dias, R., Carneiro, E. M., Boschero, A. C., and Zoppi, C. C. Exercise increases pancreatic β-cell viability in a model of type 1 diabetes through IL-6 signaling.

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Yeast flocculation (Saccharomyces cerevisiae) is one of the most important problems in fuel ethanol production. Yeast flocculation causes operational difficulties and increase in the ethanol cost. Proteolytic enzymes can solve this problem since it does not depend on these changes. The recycling of soluble papain and the immobilization of this enzyme on chitin or chitosan were studied. Some cross-linking agents were evaluated in the action of proteolytic activity of papain. The glutaraldehyde (0.1-10% w·v(-1)), polyethyleneimine (0.5% v·v(-1)), and tripolyphosphate (1-10% w·v(-1)) inactivated the enzyme in this range, respectively. Glutaraldehyde inhibited all treatments of papain immobilization. The chitosan cross-linked with TPP in 5 h of reaction showed the yield of active immobilized enzyme of 15.7% and 6.07% in chitosan treated with 0.1% PEI. Although these immobilizations have been possible, these levels have not been enough to cause deflocculation of yeast cells. Free enzyme was efficient for yeast deflocculation in dosages of 3 to 4 g·L(-1). Recycling of soluble papain by centrifugation was effective for 14 cycles with yeast suspension in time perfectly compatible to industrial conditions. The reuse of proteases applied after yeast suspension by additional yeast centrifugation could be an alternative to cost reduction of these enzymes.

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Obesity is associated with insulin resistance and is known to be a risk factor for type-2 diabetes. In obese individuals, pancreatic beta-cells try to compensate for the increased insulin demand in order to maintain euglycemia. Most studies have reported that this adaptation is due to morphological changes. However, the involvement of beta-cell functional adaptations in this process needs to be clarified. For this purpose, we evaluated different key steps in the glucose-stimulated insulin secretion (GSIS) in intact islets from female ob/ob obese mice and lean controls. Obese mice showed increased body weight, insulin resistance, hyperinsulinemia, glucose intolerance and fed hyperglycemia. Islets from ob/ob mice exhibited increased glucose-induced mitochondrial activity, reflected by enhanced NAD(P)H production and mitochondrial membrane potential hyperpolarization. Perforated patch-clamp examination of beta-cells within intact islets revealed several alterations in the electrical activity such as increased firing frequency and higher sensitivity to low glucose concentrations. A higher intracellular Ca(2+) mobilization in response to glucose was also found in ob/ob islets. Additionally, they displayed a change in the oscillatory pattern and Ca(2+) signals at low glucose levels. Capacitance experiments in intact islets revealed increased exocytosis in individual ob/ob beta-cells. All these up-regulated processes led to increased GSIS. In contrast, we found a lack of beta-cell Ca(2+) signal coupling, which could be a manifestation of early defects that lead to beta-cell malfunction in the progression to diabetes. These findings indicate that beta-cell functional adaptations are an important process in the compensatory response to obesity.

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This study investigated the presence of target bacterial species and the levels of endotoxins in teeth with apical periodontitis. Levels of inflammatory mediators (interleukin [IL]-1β and tumor necrosis factor [TNF]-α) were determined after macrophage stimulation with endodontic content after different phases of endodontic therapy using different irrigants. Thirty primarily infected root canals were randomly assigned into 3 groups according to the irrigant used for root canal preparation (n = 10 per group): GI: 2.5% sodium hypochlorite, GII: 2% chlorhexidine gel, and GIII (control group): saline solution. Root canal samples were taken by using paper points before (s1) and after root canal instrumentation (s2), subsequently to 17% EDTA (s3), after 30 days of intracanal medication (Ca[OH]2 + saline solution) (s4), and before root canal obturation (s5). Polymerase chain reaction (16S recombinant DNA) and limulus amebocyte lysate assay were used for bacterial and endotoxin detection, respectively. Macrophages were stimulated with the root canal contents for IL-1β/TNF-α measurement using enzyme-linked immunosorbent assay. Porphyromonas gingivalis (17/30), Porphyromonas endodontalis (15/30), and Prevotella nigrescens (11/30) were the most prevalent bacterial species. At s1, endotoxins were detected in 100% of the root canals (median = 32.43 EU/mL). In parallel, substantial amounts of IL-1β and TNF-α were produced by endodontic content-stimulated macrophages. At s2, a significant reduction in endotoxin levels was observed in all groups, with GI presenting the greatest reduction (P < .05). After a root canal rinse with EDTA (s3), intracanal medication (s4), and before root canal obturation (s5), endotoxin levels reduced without differences between groups (P < .05). IL-1β and TNF-α release decreased proportionally to the levels of residual endotoxin (P < .05). Regardless of the use of sodium hypochlorite or CHX, the greatest endotoxin reduction occurs after chemomechanical preparation. Increasing steps of root canal therapy associated with intracanal medication enhances endotoxin reduction, leading to a progressively lower activation of proinflammatory cells such as macrophages.

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In this study, we aimed to evaluate the effects of exenatide (EXE) treatment on exocrine pancreas of nonhuman primates. To this end, 52 baboons (Papio hamadryas) underwent partial pancreatectomy, followed by continuous infusion of EXE or saline (SAL) for 14 weeks. Histological analysis, immunohistochemistry, Computer Assisted Stereology Toolbox morphometry, and immunofluorescence staining were performed at baseline and after treatment. The EXE treatment did not induce pancreatitis, parenchymal or periductal inflammatory cell accumulation, ductal hyperplasia, or dysplastic lesions/pancreatic intraepithelial neoplasia. At study end, Ki-67-positive (proliferating) acinar cell number did not change, compared with baseline, in either group. Ki-67-positive ductal cells increased after EXE treatment (P = 0.04). However, the change in Ki-67-positive ductal cell number did not differ significantly between the EXE and SAL groups (P = 0.13). M-30-positive (apoptotic) acinar and ductal cell number did not change after SAL or EXE treatment. No changes in ductal density and volume were observed after EXE or SAL. Interestingly, by triple-immunofluorescence staining, we detected c-kit (a marker of cell transdifferentiation) positive ductal cells co-expressing insulin in ducts only in the EXE group at study end, suggesting that EXE may promote the differentiation of ductal cells toward a β-cell phenotype. In conclusion, 14 weeks of EXE treatment did not exert any negative effect on exocrine pancreas, by inducing either pancreatic inflammation or hyperplasia/dysplasia in nonhuman primates.

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This article addresses diagnostic parameters that should be assessed in the treatment of extraction sockets with dental implant placement by presenting three case reports that emphasize the relevance of the amount of remaining bone walls. Diagnosis was based on the analysis of clinical and radiographic parameters (e.g.: bone defect morphology, remaining bone volume, presence of infections on the receptor site). Case 1 presents a 5-wall defect in the maxillary right central incisor region with severe root resorption, which was treated with immediate implant placement. Cases 2 and 3 present, respectively, two- and three-wall bone defects that did not have indication for immediate implants. These cases were first submitted to a guided bone regeneration (GBR) procedure with bone graft biomaterial and membrane barriers, and the implants were installed in a second surgical procedure. The analysis of the preoperative periodontal condition of the adjacent teeth and bone defect morphology is extremely important because these factors determine the choice between immediate implant or GBR treatment followed by implant installation in a subsequent intervention.

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This study evaluated the sealing ability of different lengths of remaining root canal filling and post space preparation against coronal leakage of Enterococcus faecalis. Forty-one roots of maxillary incisors were biomechanically prepared, maintaining standardized canal diameter at the middle and coronal thirds. The roots were autoclaved and all subsequent steps were undertaken in a laminar flow chamber. The canals of 33 roots were obturated with AH Plus sealer and gutta-percha. The root canal fillings were reduced to 3 predetermined lengths (n=11): G1=6 mm, G2=4 mm and G3=2 mm. The remaining roots served as positive and negative controls. Bacterial leakage test apparatuses were fabricated with the roots attached to Eppendorf tubes keeping 2 mm of apex submerged in BHI in glass flasks. The specimens received an E. faecalis inoculum of 1 x 107 cfu/mL every 3 days and were observed for bacterial leakage daily during 60 days. Data were submitted to ANOVA, Tukey's test and Fisher's test. At 60 days, G1 (6 mm) and G2 (4 mm) presented statistically similar results (p>0.05) (54.4% of specimens with bacterial leakage) and both groups differed significantly (p<0.01) from G3 (2 mm), which presented 100% of specimens with E. faecalis leakage. It may be concluded that the shortest endodontic obturation remnant leaked considerably more than the other lengths, although none of the tested conditions avoids coronal leakage of E. faecalis.

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The South American fur seal (Arctocephalus australis) is an amphibious marine mammal distributed along the Atlantic and Pacific coasts of South America. The species is well adjusted to different habitats due to the morphology of its fin-like members and due to some adaptations in their integumentary system. Immunohistochemical studies are very important to evaluate the mechanisms of skin adaptation due the differential expression of the antigens present in the tissue depending of the region of the body surface. However, its strongly pigmented (melanin) epidermis prevents the visualization of the immuno-histochemical chromogens markers. In this study a melanin bleaching method was developed aimed to allow the visualization of the chromogens without interfering in the antigen-antibody affinity for immunohistochemistry. The analysis of PCNA (proliferating cell nuclear antigen) index in the epidermis of A. australis by immunohistochemistry with diaminobenzidine (DAB) as chromogen was used to test the method. The bleaching of the melanin allowed to obtain the cell proliferation index in epidermis and to avoid false positive results without affecting the immunohistochemical results.