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1.
Port J Card Thorac Vasc Surg ; 30(4): 71-73, 2024 Feb 09.
Article in English | MEDLINE | ID: mdl-38345881

ABSTRACT

Pulmonary artery sarcoma (PAS) is a rare and aggressive mesenchymal tumor with an overall poor prognosis1-5. Due to similar clinical and radiologic findings, PAS is often misdiagnosed as a pulmonary embolism (PE) frequently leading to prolonged anticoagulation therapy, which delays the correct diagnosis 1-3. By presenting this clinical case our objective is to emphasize characteristic CT findings that favour a neoplastic origin of a pulmonary intravascular filling defect. PET-CT and MRI have also an important potential role in its diagnosis and therapeutical management.


Subject(s)
Lung Neoplasms , Neoplasms, Vascular Tissue , Pulmonary Embolism , Sarcoma , Vascular Neoplasms , Humans , Pulmonary Artery/diagnostic imaging , Positron Emission Tomography Computed Tomography , Vascular Neoplasms/diagnosis , Pulmonary Embolism/diagnosis , Sarcoma/diagnosis , Neoplasms, Vascular Tissue/pathology , Lung Neoplasms/diagnosis
2.
J Comput Assist Tomogr ; 48(1): 92-97, 2024.
Article in English | MEDLINE | ID: mdl-37551150

ABSTRACT

OBJECTIVE: The aim of the study is to quantify observer agreement in the magnetic resonance imaging (MRI) classification of inflammatory or fibrotic interstitial lung disease (ILD). METHODS: Our study is a preliminary analysis of a larger prospective cohort. The MRI images of 18 patients with ILD (13 females; mean age, 65 years) were acquired in a 1.5 T scanner and included axial fat-saturated T2-weighted (T2-WI, n = 18) and coronal fat-saturated T1-weighted images before and 1, 3, 5, and 10 minutes after gadolinium administration (n = 16). The MRI studies were evaluated with 2 different methods: a qualitative evaluation (visual assessment and measurement of few regions of interest; evaluations were performed independently by 5 radiologists and 3 times by 1 radiologist) and a segmentation-based analysis with software extraction of signal intensity values (evaluations were performed independently by 2 radiologists and twice by 1 radiologist). Interstitial lung disease was classified as inflammatory or fibrotic, based on previously described imaging criteria. RESULTS: Regarding the qualitative evaluation, intraobserver agreement was excellent (κ = 0.92, P < 0.05) for T2-WI and fair (κ = 0.29, P < 0.05) for T1 dynamic study, while interobserver agreement was moderate (κ = 0.56, P < 0.05) and poor (κ = 0.11, P = 0.18), respectively. In contrast, upon segmentation-based analysis, intraobserver and interobserver agreement were excellent for T2-WI (κ = 0.886, P < 0.001; κ = 1.00, P < 0.001; respectively); for T1-WI, intraobserver agreement was excellent (κ = 0.87, P < 0.05) and interobserver agreement was good (κ = 0.75, P < 0.05). CONCLUSIONS: Segmentation-based MRI analysis is more reproducible than a qualitative evaluation with visual assessment and measurement of few regions of interest.


Subject(s)
Lung Diseases, Interstitial , Magnetic Resonance Imaging , Female , Humans , Aged , Prospective Studies , Retrospective Studies , Magnetic Resonance Imaging/methods , Lung Diseases, Interstitial/diagnostic imaging , Observer Variation
3.
J Belg Soc Radiol ; 107(1): 53, 2023.
Article in English | MEDLINE | ID: mdl-37483991

ABSTRACT

Teaching Point: Lipoblastoma should be considered in the differential diagnosis of painful rapidly growing fatty mass within the mediastinum in infants or young children under three years old.

4.
J Belg Soc Radiol ; 107(1): 14, 2023.
Article in English | MEDLINE | ID: mdl-36846552

ABSTRACT

A four-month-old girl presented with recurrent low gastrointestinal hemorrhage. Abdominal ultrasound showed diffuse parietal thickening and hyperemia of the colon. Computed tomography (CT) demonstrated diffuse thickening of the colon but also intense arterial globular mural enhancement with diffuse filling in the portal phase. Colonoscopy revealed multiple pseudopolipoid lesions along the colon which were histologically diagnosed as hemangiomas. The infant was diagnosed with gastrointestinal hemangiomatosis and was treated with propranolol resulting in complete resolution of symptoms. Teaching point: Although rare, the possibility of intestinal hemangiomatosis should be considered in the setting of rectal bleeding in an infant.

5.
Gut ; 68(1): 83-93, 2019 01.
Article in English | MEDLINE | ID: mdl-29097438

ABSTRACT

OBJECTIVE: To investigate whether a whole grain diet alters the gut microbiome and insulin sensitivity, as well as biomarkers of metabolic health and gut functionality. DESIGN: 60 Danish adults at risk of developing metabolic syndrome were included in a randomised cross-over trial with two 8-week dietary intervention periods comprising whole grain diet and refined grain diet, separated by a washout period of ≥6 weeks. The response to the interventions on the gut microbiome composition and insulin sensitivity as well on measures of glucose and lipid metabolism, gut functionality, inflammatory markers, anthropometry and urine metabolomics were assessed. RESULTS: 50 participants completed both periods with a whole grain intake of 179±50 g/day and 13±10 g/day in the whole grain and refined grain period, respectively. Compliance was confirmed by a difference in plasma alkylresorcinols (p<0.0001). Compared with refined grain, whole grain did not significantly alter glucose homeostasis and did not induce major changes in the faecal microbiome. Also, breath hydrogen levels, plasma short-chain fatty acids, intestinal integrity and intestinal transit time were not affected. The whole grain diet did, however, compared with the refined grain diet, decrease body weight (p<0.0001), serum inflammatory markers, interleukin (IL)-6 (p=0.009) and C-reactive protein (p=0.003). The reduction in body weight was consistent with a reduction in energy intake, and IL-6 reduction was associated with the amount of whole grain consumed, in particular with intake of rye. CONCLUSION: Compared with refined grain diet, whole grain diet did not alter insulin sensitivity and gut microbiome but reduced body weight and systemic low-grade inflammation. TRIAL REGISTRATION NUMBER: NCT01731366; Results.


Subject(s)
Gastrointestinal Microbiome , Inflammation/blood , Weight Loss , Whole Grains , Adult , Aged , Blood Glucose/metabolism , Cross-Over Studies , Denmark , Diet , Energy Intake , Feces/microbiology , Female , Humans , Inflammation/diet therapy , Insulin Resistance , Interleukin-6/blood , Lipids/blood , Male , Metabolomics , Middle Aged
6.
Nat Commun ; 9(1): 4630, 2018 11 13.
Article in English | MEDLINE | ID: mdl-30425247

ABSTRACT

Adherence to a low-gluten diet has become increasingly common in parts of the general population. However, the effects of reducing gluten-rich food items including wheat, barley and rye cereals in healthy adults are unclear. Here, we undertook a randomised, controlled, cross-over trial involving 60 middle-aged Danish adults without known disorders with two 8-week interventions comparing a low-gluten diet (2 g gluten per day) and a high-gluten diet (18 g gluten per day), separated by a washout period of at least six weeks with habitual diet (12 g gluten per day). We find that, in comparison with a high-gluten diet, a low-gluten diet induces moderate changes in the intestinal microbiome, reduces fasting and postprandial hydrogen exhalation, and leads to improvements in self-reported bloating. These observations suggest that most of the effects of a low-gluten diet in non-coeliac adults may be driven by qualitative changes in dietary fibres.


Subject(s)
Diet , Gastrointestinal Microbiome , Glutens/administration & dosage , Glutens/adverse effects , Adult , Aged , Body Mass Index , Creatinine/urine , Cross-Over Studies , Cytokines/blood , DNA, Bacterial/analysis , Denmark , Fasting , Feces/microbiology , Female , Fermentation , Gastrointestinal Microbiome/genetics , Humans , Hydrogen , Intestines/microbiology , Male , Metabolomics , Metagenomics , Middle Aged , Postprandial Period , Self Report , Young Adult
7.
Nat Microbiol ; 1(9): 16093, 2016 Jun 27.
Article in English | MEDLINE | ID: mdl-27562254

ABSTRACT

Little is known about how colonic transit time relates to human colonic metabolism and its importance for host health, although a firm stool consistency, a proxy for a long colonic transit time, has recently been positively associated with gut microbial richness. Here, we show that colonic transit time in humans, assessed using radio-opaque markers, is associated with overall gut microbial composition, diversity and metabolism. We find that a long colonic transit time associates with high microbial richness and is accompanied by a shift in colonic metabolism from carbohydrate fermentation to protein catabolism as reflected by higher urinary levels of potentially deleterious protein-derived metabolites. Additionally, shorter colonic transit time correlates with metabolites possibly reflecting increased renewal of the colonic mucosa. Together, this suggests that a high gut microbial richness does not per se imply a healthy gut microbial ecosystem and points at colonic transit time as a highly important factor to consider in microbiome and metabolomics studies.


Subject(s)
Gastrointestinal Microbiome , Gastrointestinal Transit , Metabolome , Adult , Aged , Biomarkers/metabolism , Carbohydrate Metabolism , Colon/metabolism , Feces/microbiology , Female , Fermentation , Humans , Male , Metabolism , Middle Aged , Mucous Membrane/metabolism , Proteins/metabolism , Reproducibility of Results , Young Adult
8.
PLoS One ; 10(12): e0144854, 2015.
Article in English | MEDLINE | ID: mdl-26691591

ABSTRACT

Antibiotics are frequently administered orally to treat bacterial infections not necessarily related to the gastrointestinal system. This has adverse effects on the commensal gut microbial community, as it disrupts the intricate balance between specific bacterial groups within this ecosystem, potentially leading to dysbiosis. We hypothesized that modulation of community composition and function induced by antibiotics affects intestinal integrity depending on the antibiotic administered. To address this a total of 60 Wistar rats (housed in pairs with 6 cages per group) were dosed by oral gavage with either amoxicillin (AMX), cefotaxime (CTX), vancomycin (VAN), metronidazole (MTZ), or water (CON) daily for 10-11 days. Bacterial composition, alpha diversity and caecum short chain fatty acid levels were significantly affected by AMX, CTX and VAN, and varied among antibiotic treatments. A general decrease in diversity and an increase in the relative abundance of Proteobacteria was observed for all three antibiotics. Additionally, the relative abundance of Bifidobacteriaceae was increased in the CTX group and both Lactobacillaceae and Verrucomicrobiaceae were increased in the VAN group compared to the CON group. No changes in microbiota composition or function were observed following MTZ treatment. Intestinal permeability to 4 kDa FITC-dextran decreased after CTX and VAN treatment and increased following MTZ treatment. Plasma haptoglobin levels were increased by both AMX and CTX but no changes in expression of host tight junction genes were found in any treatment group. A strong correlation between the level of caecal succinate, the relative abundance of Clostridiaceae 1 family in the caecum, and the level of acute phase protein haptoglobin in blood plasma was observed. In conclusion, antibiotic-induced changes in microbiota may be linked to alterations in intestinal permeability, although the specific interactions remain to be elucidated as changes in permeability did not always result from major changes in microbiota and vice versa.


Subject(s)
Anti-Bacterial Agents/pharmacology , Bacteria/growth & development , Gastrointestinal Microbiome/drug effects , Intestines/microbiology , Animals , Female , Haptoglobins/metabolism , Intestinal Mucosa/metabolism , Permeability/drug effects , Rats , Rats, Wistar
9.
Biotechnol Adv ; 33(3-4): 358-69, 2015.
Article in English | MEDLINE | ID: mdl-25689072

ABSTRACT

Carbohydrate-binding modules (CBMs) are small components of several enzymes, which present an independent fold and function, and specific carbohydrate-binding activity. Their major function is to bind the enzyme to the substrate enhancing its catalytic activity, especially in the case of insoluble substrates. The immense diversity of CBMs, together with their unique properties, has long raised their attention for many biotechnological applications. Recombinant DNA technology has been used for cloning and characterizing new CBMs. In addition, it has been employed to improve the purity and availability of many CBMs, but mainly, to construct bi-functional CBM-fused proteins for specific applications. This review presents a comprehensive summary of the uses of CBMs recombinantly produced from heterologous organisms, or by the original host, along with the latest advances. Emphasis is given particularly to the applications of recombinant CBM-fusions in: (a) modification of fibers, (b) production, purification and immobilization of recombinant proteins, (c) functionalization of biomaterials and (d) development of microarrays and probes.


Subject(s)
Biotechnology , Carbohydrates/chemistry , Receptors, Cell Surface/genetics , Recombinant Proteins/genetics , Cellulose/genetics , Cellulose/metabolism , Immobilized Proteins/chemistry , Immobilized Proteins/genetics , Receptors, Cell Surface/chemistry , Receptors, Cell Surface/metabolism , Recombinant Proteins/chemistry , Recombinant Proteins/isolation & purification , Substrate Specificity
10.
Microbiome ; 2: 19, 2014.
Article in English | MEDLINE | ID: mdl-24949196

ABSTRACT

BACKGROUND: In recent years, studies on the human intestinal microbiota have attracted tremendous attention. Application of next generation sequencing for mapping of bacterial phylogeny and function has opened new doors to this field of research. However, little attention has been given to the effects of choice of methodology on the output resulting from such studies. RESULTS: IN THIS STUDY WE CONDUCTED A SYSTEMATIC COMPARISON OF THE DNA EXTRACTION METHODS USED BY THE TWO MAJOR COLLABORATIVE EFFORTS: The European MetaHIT and the American Human Microbiome Project (HMP). Additionally, effects of homogenizing the samples before extraction were addressed. We observed significant differences in distribution of bacterial taxa depending on the method. While eukaryotic DNA was most efficiently extracted by the MetaHIT protocol, DNA from bacteria within the Bacteroidetes phylum was most efficiently extracted by the HMP protocol. CONCLUSIONS: Whereas it is comforting that the inter-individual variation clearly exceeded the variation resulting from choice of extraction method, our data highlight the challenge of comparing data across studies applying different methodologies.

11.
Eur J Nutr ; 52(3): 1233-42, 2013 Apr.
Article in English | MEDLINE | ID: mdl-22890505

ABSTRACT

PURPOSE: It has been demonstrated that reabsorption of Na⁺ in the thick ascending limb is reduced and the ability to concentrate urine can be compromised in undernourished individuals. Alterations in phospholipid and cholesterol content in renal membranes, leading to Na⁺ loss and the inability to concentrate urine, were investigated in undernourished rats. METHODS: Sixty-day-old male Wistar rats were utilized to evaluate (1) phospholipid and cholesterol content in the membrane fraction of whole kidneys, (2) cholesterol content and the levels of active Na⁺ transporters, (Na⁺ + K⁺)ATPase and Na⁺-ATPase, in basolateral membranes of kidney proximal tubules, and (3) functional indicators of medullary urine concentration. RESULTS: Body weight in the undernourished group was 73 % lower than in control. Undernourishment did not affect the levels of cholesterol in serum or in renal homogenates. However, membranes of whole kidneys revealed 56 and 66 % reduction in the levels of total phospholipids and cholesterol, respectively. Furthermore, cholesterol and (Na⁺ + K⁺)ATPase activity in proximal tubule membranes were reduced by 55 and 68 %, respectively. Oxidative stress remained unaltered in the kidneys of undernourished rats. In contrast, Na⁺-ATPase activity, an enzyme with all regulatory components in membrane, was increased in the proximal tubules of undernourished rats. Free water clearance and fractional Na⁺ excretion were increased by 86 and 24 %, respectively, and urinary osmolal concentration was 21 % lower in undernourished rats than controls. CONCLUSION: Life-long undernutrition reduces the levels of total phospholipids and cholesterol in membranes of renal tubular cells. This alteration in membrane integrity could diminish (Na⁺ + K⁺)ATPase activity resulting in reduced Na⁺ reabsorption and urinary concentrating ability.


Subject(s)
Cell Membrane/metabolism , Cholesterol/metabolism , Down-Regulation , Kidney Concentrating Ability , Malnutrition/metabolism , Renal Insufficiency/etiology , Adenosine Triphosphatases/metabolism , Animals , Cation Transport Proteins/metabolism , Cell Membrane/enzymology , Female , Kidney/cytology , Kidney/enzymology , Kidney/metabolism , Kidney/physiopathology , Kidney Tubules, Proximal/enzymology , Kidney Tubules, Proximal/metabolism , Kidney Tubules, Proximal/physiopathology , Lactation , Male , Malnutrition/congenital , Malnutrition/physiopathology , Malnutrition/urine , Maternal Nutritional Physiological Phenomena , Phospholipids/metabolism , Pregnancy , Rats , Rats, Wistar , Sodium/urine , Sodium-Potassium-Exchanging ATPase/metabolism
12.
J Biomed Nanotechnol ; 8(3): 473-81, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22764417

ABSTRACT

Amphiphilic mannan, produced by the Michael addition of hydrophobic 1-hexadecanethiol to vinyl methacrylated mannan, self-assembles in aqueous medium through hydrophobic interactions among alkyl chains. Resultant nanogel is stable, spherical, polydisperse, with 50-140 nm mean hydrodynamic diameter depending on the polymer degree of substitution, and nearly neutral negative surface charge. No cytotoxicity of mannan nanogel is detected up to about 0.4 mg/mL in mouse embryo fibroblast cell line 3T3 and mouse bone marrow-derived macrophages (BMDM) using cell proliferation, lactate dehydrogenase and Live/Dead assays. Comet assay, under the tested conditions, reveals no DNA damage in fibroblasts but possible in BMDM. BMDM internalize the mannan nanogel, which is observed in vesicles in the cytoplasm by confocal laser scanning microscopy. Confocal colocalization image analysis denotes that the entrance and exit of nanogel and FM 4-64 might occur by the same processes--endocytosis and exocytosis--in BMDM. Physicochemical characteristics, in vitro cytocompatibility and uptake of self-assembled mannan nanogel by mouse BMDM are great signals of the potential applicability of this nanosystem for macrophages targeted delivery of vaccines or drugs, acting as potential nanomedicines, always with the key goal of preventing and/or treating diseases.


Subject(s)
Macrophages/chemistry , Macrophages/drug effects , Mannans/chemistry , Mannans/pharmacology , Nanoparticles/administration & dosage , Nanoparticles/chemistry , Subcellular Fractions/chemistry , 3T3 Cells , Animals , Cell Survival/drug effects , Female , Gels/chemistry , Gels/pharmacology , Materials Testing , Mice , Mice, Inbred BALB C
13.
Biomacromolecules ; 13(2): 517-27, 2012 Feb 13.
Article in English | MEDLINE | ID: mdl-22288730

ABSTRACT

Dextrin, a glucose polymer with low molecular weight, was used to develop a fully resorbable hydrogel, without using chemical initiators. Dextrin was first oxidized (oDex) with sodium periodate and then cross-linked with adipic acid dihidrazide, a nontoxic cross-linking molecule. Furthermore, a new bidimensional composite hydrogel, made of oxidized dextrin incorporating dextrin nanogels (oDex-nanogel), was also developed. The oDex hydrogels showed good mechanical properties and biocompatibility, allowing the proliferation of mouse embryo fibroblasts 3T3 cultured on top of the gel. The gelation time may be controlled selecting the concentrations of the polymer and reticulating agent. Both the oDex and oDex-nanogel hydrogels are biodegradable and present a 3-D network with a continuous porous structure. The obtained hybrid hydrogel enables the release of the dextrin nanogel over an extended period of time, paralleling the mass loss curve due to the degradation of the material. The dextrin nanogel allowed the efficient incorporation of interleukin-10 and insulin in the oDex hydrogel, providing a sophisticated system of controlled release. The new hydrogels present promising properties as an injectable carrier of bioactive molecules. Both proteins and poorly water-soluble low-molecular-weight drugs are efficiently encapsulated in the nanogel, which performs as a controlled release system entrapped in the hydrogel matrix.


Subject(s)
Biocompatible Materials/chemical synthesis , Delayed-Action Preparations/chemical synthesis , Dextrins/chemistry , Hydrogels/chemistry , Polyethylene Glycols/chemistry , Polyethyleneimine/chemistry , 3T3 Cells , Adipates/chemistry , Animals , Biocompatible Materials/chemistry , Biocompatible Materials/metabolism , Biotransformation , Cell Survival , Cross-Linking Reagents/chemistry , Delayed-Action Preparations/chemistry , Delayed-Action Preparations/metabolism , Fluorescein-5-isothiocyanate , Insulin/administration & dosage , Insulin/chemistry , Interleukin-10/administration & dosage , Interleukin-10/chemistry , Kinetics , Magnetic Resonance Spectroscopy , Mice , Microscopy, Electron, Scanning , Nanogels , Periodic Acid/chemistry , Polymers/chemistry , Polymers/metabolism , Porosity , Proteins/chemistry , Proteins/metabolism
14.
Biotechnol Bioeng ; 108(8): 1977-86, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21391205

ABSTRACT

Interleukin-10 (IL-10) is an anti-inflammatory cytokine, which active form is a non-covalent homodimer. Given the potential of IL-10 for application in various medical conditions, it is essential to develop systems for its effective delivery. In previous work, it has been shown that a dextrin nanogel effectively incorporated and stabilized rIL-10, enabling its release over time. In this work, the delivery system based on dextrin nanogels was further analyzed. The biocompatibility of the nanogel was comprehensively analyzed, through cytotoxicity (lactate dehydrogenase (LDH) release, MTS, Live, and Dead) and genotoxicity (comet) assays. The release profile of rIL-10 and its biological activity were evaluated in vivo, using C57BL/6 mice. Although able to maintain a stable concentration of IL-10 for at least 4 h in mice serum, the amount of protein released was rather low. Despite this, the amount of rIL-10 released from the complex was biologically active inhibiting TNF-α production, in vivo, by LPS-challenged mice. In spite of the significant stabilization achieved using the nanogel, rIL-10 still denatures rather quickly. An additional effort is thus necessary to develop an effective delivery system for this cytokine, able to release active protein over longer periods of time. Nevertheless, the good biocompatibility, the protein stabilization effect and the ability to perform as a carrier with controlled release suggest that self-assembled dextrin nanogels may be useful protein delivery systems.


Subject(s)
Dextrins/administration & dosage , Drug Carriers/administration & dosage , Immunologic Factors/pharmacology , Immunologic Factors/pharmacokinetics , Interleukin-10/pharmacology , Interleukin-10/pharmacokinetics , Polyethylene Glycols/administration & dosage , Polyethyleneimine/administration & dosage , Animals , Dextrins/adverse effects , Drug Carriers/adverse effects , Mice , Mice, Inbred C57BL , Nanogels , Polyethylene Glycols/adverse effects , Polyethyleneimine/adverse effects , Protein Denaturation , Serum/chemistry
15.
Int J Pharm ; 400(1-2): 234-42, 2010 Nov 15.
Article in English | MEDLINE | ID: mdl-20816730

ABSTRACT

Interleukin-10 (IL-10) is an anti-inflammatory cytokine, which active form is a non-covalent homodimer with two intramolecular disulphide bonds essential for its biological activity. A mutated form of murine IL-10 was successfully expressed in E. coli, recovered and purified from inclusion bodies. Its ability to reduce tumor necrosis factor α synthesis and down-regulate class II major histocompatibility complex molecules expression on endotoxin-stimulated bone marrow-derived macrophages was confirmed, and shown to be similar to that of a commercially available IL-10. Given the potential of IL-10 for application in various medical conditions, it is essential to develop systems that can effectively deliver the protein. In this work it is shown that a dextrin nanogel effectively incorporate IL-10, stabilize, and enable the slow release of biologically active IL-10 over time. Altogether, these results demonstrate the suitability of dextrin nanogel to be used as a system for the controlled release of IL-10.


Subject(s)
Dextrins/chemistry , Drug Carriers/chemistry , Interleukin-10/administration & dosage , Polyethylene Glycols/chemistry , Polyethyleneimine/chemistry , Animals , Delayed-Action Preparations , Down-Regulation , Escherichia coli/genetics , Escherichia coli/metabolism , Histocompatibility Antigens Class II/biosynthesis , Histocompatibility Antigens Class II/genetics , Interleukin-10/genetics , Interleukin-10/isolation & purification , Macrophages/drug effects , Macrophages/metabolism , Mice , Nanogels , Recombinant Proteins/administration & dosage , Recombinant Proteins/genetics , Recombinant Proteins/isolation & purification , Tumor Necrosis Factor-alpha/biosynthesis , Tumor Necrosis Factor-alpha/genetics
16.
Mol Biotechnol ; 40(3): 269-79, 2008 Nov.
Article in English | MEDLINE | ID: mdl-18677572

ABSTRACT

Biomaterials used for tissue engineering applications must provide a structural support for the tissue development and also actively interact with cells, promoting adhesion, proliferation, and differentiation. To achieve this goal, adhesion molecules may be used, such as the tripeptide Arg-Gly-Asp (RGD). A method based on the use of a carbohydrate-binding module, with affinity for chitin, was tested as an alternative approach to the chemical grafting of bioactive peptides. This approach would simultaneously allow the production of recombinant peptides (alternatively to peptide synthesis) and provide a simple way for the specific and strong adsorption of the peptides to the biomaterial.A fusion recombinant protein, containing the RGD sequence fused to a human chitin-binding module (ChBM), was expressed in E. coli. The adhesion of fibroblasts to reacetylated chitosan (RC) films was the model system selected to analyze the properties of the obtained proteins. Thus, the evaluation of cell attachment and proliferation on polystyrene surfaces and reacetylated chitosan films, coated with the recombinant proteins, was performed using mouse embryo fibroblasts 3T3. The results show that the recombinant proteins affect negatively fibroblasts anchorage to the materials surface, inhibiting its adhesion and proliferation. We also conclude that this negative effect is fundamentally due to the human chitin-binding domain.


Subject(s)
Chitin/pharmacology , Chitosan/metabolism , Fibroblasts/cytology , Fibroblasts/drug effects , Oligopeptides/pharmacology , Recombinant Fusion Proteins/pharmacology , 3T3 Cells , Acetylation/drug effects , Amino Acid Sequence , Animals , Cell Adhesion/drug effects , Cell Death/drug effects , Cell Survival/drug effects , Chitin/chemistry , Electrophoresis, Polyacrylamide Gel , Humans , Mice , Microscopy, Fluorescence , Molecular Sequence Data , Polystyrenes , Protein Structure, Tertiary , Recombinant Fusion Proteins/biosynthesis , Recombinant Fusion Proteins/chemistry
17.
Biotechnol Lett ; 28(16): 1279-84, 2006 Aug.
Article in English | MEDLINE | ID: mdl-16802098

ABSTRACT

A novel hydrogel was obtained by reticulation of chitosan with dextrin enzymatically linked to vinyl acrylate (dextrin-VA), without cross-linking agents. The hydrogel had a solid-like behaviour with G' (storage modulus) >> G'' (loss modulus). Glucose diffusion coefficients of 3.9 x 10(-6) +/- 1.3 x 10(-6) cm(2)/s and 2.9 x 10(-6) +/- 0.5 x 10(-6) cm(2)/s were obtained for different substitution degrees of the dextrin-VA (20% and 70% respectively). SEM observation revealed a porous structure, with pores ranging from 50 microm to 150 microm.


Subject(s)
Acrylates/chemistry , Biotechnology/methods , Chitosan/chemistry , Dextrins/chemistry , Hydrogel, Polyethylene Glycol Dimethacrylate/chemistry , Biotechnology/instrumentation , Carbohydrate Conformation , Diffusion , Hydrogels/chemistry , Hydrogen-Ion Concentration , Magnetic Resonance Spectroscopy , Microscopy, Electron, Scanning , Models, Chemical , Polymers/chemistry , Rheology , Time Factors
18.
Espaç. saúde (Online) ; 7(2): 1-7, jun. 2006. tab
Article in Portuguese | LILACS | ID: lil-442888

ABSTRACT

Este trabalho foi desenvolvido com o objetivo de aplicar e analisar uma atividade de educação em saúde bucal para idosos. A população de estudo foi composta por pessoas com idade entre 60 a 74 anos, inscritos no Programa Saúde da Família de um bairro do município de Londrina (PR). Os idosos participaram de palestra e atividade prática, que tiveram como tema a prevenção de doenças bucais, com a realização de escovação orientada e auto-exame bucal. Após 20 dias, os idosos responderam, em visitas domiciliares, a um formulário contendo questões sobre avaliação da atividade educativa, autopercepção da saúde bucal, além de variáveis sócio-econômicas e de identificação. Participaram do estudo 73 idosos, sendo 57,5 (por cento)mulheres e 68,5 (por cento) com menos de quatro anos de escolaridade. Foram identificados 83,6 (por cento) de idosos que nunca haviam participado de atividades educativas. Todos os participantes desta atividade acharam importante ensinar o que aprenderam para outras pessoas, 91,8 (por cento)declararam que conseguiriam ensinar o que aprenderam e 94,5 (por cento) referiram ter melhorado seus cuidados com a boca. Quanto à autopercepção, cerca de 75 (por cento) consideraram sua saúde bucal boa ou regular. Pode-se dizer que a educação em saúde bucal voltada para idosos deve respeitar particularidades do envelhecimento, como por exemplo, tempo maior para aplicações práticas e fala mais lenta e pausada em palestras. Considerando a baixa escolaridade e a acuidade visual reduzida, deve-se priorizar o uso de imagens em relação a textos. Para maior adesão às atividades práticas em atividades educativas, deve-se garantir maior privacidade ao idoso. A educação em saúde bucal voltada para idosos deve ser desenvolvida e ampliada, considerando as necessidades desse grupo populacional, além da possibilidade de se tornarem importantes disseminadores das informações


Subject(s)
Humans , Self Concept , Health Education , Aged , Oral Health
19.
Carbohydr Res ; 339(15): 2555-66, 2004 Oct 20.
Article in English | MEDLINE | ID: mdl-15476717

ABSTRACT

The structure and bioactivity of a polysaccharide extracted and purified from a 4M KOH + H3BO3 solution from Prunus dulcis seed cell wall material was studied. Anion-exchange chromatography of the crude extract yielded two sugar-rich fractions: one neutral (A), the other acidic (E). These fractions contain a very similar monosaccharide composition: 5:2:1 for arabinose, uronic acids and xylose, respectively, rhamnose and galactose being present in smaller amounts. As estimated by size-exclusion chromatography, the acidic fraction had an apparent molecular mass of 762 kDa. Methylation analysis (from the crude and fractions A and E), suggests that the polysaccharide is an arabinan-rich pectin. In all cases, the polysaccharides bear the same type of structural Ara moieties with highly branched arabinan-rich pectic polysaccharides. The average relative proportions of the arabinosyl linkages is 3:2:1:1 for T-Araf:(1-->5)-Araf:(1-->3,5)-Araf:(1-->2,3,5)-Araf. The crude polysaccharide extract and fractions A and E induced a murine lymphocyte stimulatory effect, as evaluated by the in vitro and in vivo expression of lymphocyte activation markers and spleen mononuclear cells culture proliferation. The lymphocyte stimulatory effect was stronger on B- than on T-cells. No evidence of cytotoxic effects induced by the polysaccharide fractions was found.


Subject(s)
Pectins/immunology , Polysaccharides , Prunus/chemistry , Animals , B-Lymphocytes/immunology , Cell Wall/chemistry , Cells, Cultured , Lymphocyte Activation/immunology , Macrophages/immunology , Mice , Pectins/isolation & purification , Seeds/chemistry , T-Lymphocytes/immunology
20.
Rev Soc Bras Med Trop ; 37(1): 37-40, 2004.
Article in Portuguese | MEDLINE | ID: mdl-15042181

ABSTRACT

Little information is available on the lipid changes caused by Schistosoma mansoni reinfection. In this work it was evaluated alteration in the plasma lipids due to one reinfection by Schistosoma mansoni in the non human primate Callithrix jacchus (sagüi). Blood samples from C. jacchus, prior and after 60 days infection and reinfection, were collected by intravenous puncture, anticoagulated with EDTA (1mg/mL) and centrifuged at 2,500 xg, in order to obtain the plasma. Total cholesterol, cholesteryl ester, total phospholipid and triglyceride levels were determined by spectrophotometer methods. The results showed that there are significant reduction in cholesterol total, cholesteryl ester, total phospholipid and triglyceride concentrations in plasma of animals reinfected by Schistosoma mansoni, in comparison to the same animals prior and after one infection. This study showed that a second infection of Callithrix jacchus by Schistosoma mansoni causes plasma lipid alterations, which are more significant than after a single infection.


Subject(s)
Callithrix/blood , Cholesterol/blood , Phospholipids/blood , Schistosomiasis mansoni/blood , Triglycerides/blood , Animals , Callithrix/parasitology , Male , Recurrence , Spectrophotometry
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