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1.
J Synchrotron Radiat ; 31(Pt 2): 363-377, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38386565

RESUMO

The ForMAX beamline at the MAX IV Laboratory provides multiscale and multimodal structural characterization of hierarchical materials in the nanometre to millimetre range by combining small- and wide-angle X-ray scattering with full-field microtomography. The modular design of the beamline is optimized for easy switching between different experimental modalities. The beamline has a special focus on the development of novel fibrous materials from forest resources, but it is also well suited for studies within, for example, food science and biomedical research.

2.
Can J Kidney Health Dis ; 10: 20543581221132748, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36700057

RESUMO

Background: Chronic kidney disease (CKD) is a global health problem. As it progresses to end stages, renal replacement therapy is required but ultimately, the best treatment is transplantation. Decreased renal function has been associated with an inflammatory state associated to primary CKD and in kidney transplant recipients (KTRs). Objective: To establish how the serum concentrations of some cytokines, such as interleukin (IL)-2, IL-8, IL-22, IL-17α, interferon-gamma, IL-4, and transforming growth factor-ß, correlate with various CKD stages. Methods: One hundred and forty-one KTRs between the ages of 18 and 75 years were included in the study. We also included 112 live kidney donors, 37 CKD PGCKD+3, and 76 GPhealthy. Participants were grouped according to their glomerular filtration rate (GFR) and their circulating cytokine levels, previously quantified by ELISA. Results: By linear regression analysis, we established the relation of each cytokine with the GFR. Transforming growth factor-ß correlated positively with the GFR in the study population, except in healthy individuals. A negative correlation of IL-8 and IL-17α and GFR was found in all cases. Conclusions: Whether these cytokines (IL-8 and IL-17α) could be used as inflammatory biomarkers indicating CKD progression, regardless of the type of population, remains to be prospectively determined.


Contexte: L'insuffisance rénale chronique (IRC) est un problème de santé mondial. Une thérapie de remplacement rénal est nécessaire au fur et à mesure que la maladie évolue vers les stades terminaux. Mais, en définitive, le meilleur traitement reste la transplantation. La réduction de la fonction rénale a été associée à un état inflammatoire associé à l'IRC primaire; une association observée aussi chez les receveurs d'une greffe de rein. Objectif: Déterminer la façon dont les concentrations sériques de certaines cytokines, notamment IL-2, IL-8, IL-22, IL-17a, IFN-γ, IL-4 et TGF-ß, corrèlent avec divers stades de l'IRC. Méthodologie: Ont été inclus dans l'étude 141 receveurs d'une greffe rénale âgés de 18 à 75 ans, 112 donneurs vivants de rein, 37 personnes atteintes d'IRC (PGIRC+3) et 76 personnes en bonne santé (PGen santé). Les sujets ont été regroupés en fonction de leur débit de filtration glomérulaire (DFGe) et de leur taux de cytokines en circulation, quantifiés préalablement par ELISA. Résultats: Une analyse de régression linéaire a servi à établir la relation entre chaque cytokine et le DFGe. Dans la population étudiée, une corrélation positive a été observée entre TGF-ß et le DFGe, sauf chez les individus sains. Dans tous les cas, la corrélation s'est avérée négative entre le DFGe et les taux d'IL-8 et d'IL-17a. Conclusion: Il reste à déterminer prospectivement si ces cytokines (IL-8 et IL-17a) pourraient être utilisées comme biomarqueurs inflammatoires pour indiquer la progression de l'IRC, quelle que soit la population.

3.
Stud Mycol ; 96: 141-153, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32206138

RESUMO

Dothideomycetes is the largest class of kingdom Fungi and comprises an incredible diversity of lifestyles, many of which have evolved multiple times. Plant pathogens represent a major ecological niche of the class Dothideomycetes and they are known to infect most major food crops and feedstocks for biomass and biofuel production. Studying the ecology and evolution of Dothideomycetes has significant implications for our fundamental understanding of fungal evolution, their adaptation to stress and host specificity, and practical implications with regard to the effects of climate change and on the food, feed, and livestock elements of the agro-economy. In this study, we present the first large-scale, whole-genome comparison of 101 Dothideomycetes introducing 55 newly sequenced species. The availability of whole-genome data produced a high-confidence phylogeny leading to reclassification of 25 organisms, provided a clearer picture of the relationships among the various families, and indicated that pathogenicity evolved multiple times within this class. We also identified gene family expansions and contractions across the Dothideomycetes phylogeny linked to ecological niches providing insights into genome evolution and adaptation across this group. Using machine-learning methods we classified fungi into lifestyle classes with >95 % accuracy and identified a small number of gene families that positively correlated with these distinctions. This can become a valuable tool for genome-based prediction of species lifestyle, especially for rarely seen and poorly studied species.

4.
J Photochem Photobiol B ; 178: 302-309, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29175604

RESUMO

In recent years, the management of food waste processing has emerged as a major concern. One such type of food waste, grape pomace, has been shown to be a great source of bioactive compounds which might be used for more environmentally - friendly processes for the synthesis of nanomaterials. In this study, grape pomace of Vitis vinifera has been used for the obtainment of an aqueous extract. Firstly, the reducing activity, total phenolic content and DPPH scavenging activity of the aqueous extract were determined. Then, the aqueous extract was used for the synthesis of gold and silver nanoparticles. The formation of spherical and stable nanoparticles with mean diameters of 35.3±5.2nm for Au@GP and 42.9±6.4nm for Ag@GP was confirmed by UV-vis spectroscopy and transmission electron microscopy. Furthermore, the functional group of biomolecules present in grape pomace extract, Au@GP and Ag@GP, were characterized by Fourier transform infrared spectroscopy prior to and after the synthesis, in order to obtain information about the biomolecules involved in the reducing and stabilization process. This study is the first to deal with the use of Vitis vinifera grape pomace in obtaining gold and silver nanoparticles through an eco-friendly, quick, one-pot synthetic route.


Assuntos
Ouro/química , Nanopartículas Metálicas/química , Prata/química , Vitis/química , Química Verde , Microscopia Eletrônica de Transmissão , Tamanho da Partícula , Extratos Vegetais/química , Espectrofotometria , Espectroscopia de Infravermelho com Transformada de Fourier , Vitis/metabolismo
5.
Colloids Surf B Biointerfaces ; 153: 190-198, 2017 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-28242372

RESUMO

This study is the first dealt with the use of brown macroalgae Cystoseira baccata (CB) extracts in obtaining gold nanoparticles (Au@CB) through an eco-friendly, fast, one-pot synthetic route. The formation of spherical, stable, polycrystalline nanoparticles with mean diameter of 8.4±2.2nm was demonstrated by UV-vis spectroscopy, TEM, HRTEM, STEM and zeta potential measurements. The extract appears to act as a protective agent where the particles are embedded, keeping them separated, avoiding aggregation and coalescence. The EELS and EDS analyses confirmed the elemental composition of the extract and nanoparticles. Moreover, the functional group of biomolecules present in CB and Au@CB were characterized by FTIR. The effects of CB extract and Au@CB were tested in vitro on the colon cancer cell lines HT-29 and Caco-2, as well as on normal primary neonatal dermal fibroblast cell line PCS-201-010. Results show a stronger cytotoxic effect against HT-29 than that on Caco-2; interestingly, a lack of toxicity on PCS-201-010 was obtained. Finally, the apoptotic activity was determined; Au@CB is able to induce apoptosis activation by the extrinsic and mitochondrial pathway in our CRC in vitro model. These encouraging results suggest that Au@CB has a significant potential for the treatment of colon rectal cancer.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Colorretais/tratamento farmacológico , Ouro/farmacologia , Química Verde , Nanopartículas Metálicas/química , Phaeophyceae/química , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Células CACO-2 , Extratos Celulares/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Neoplasias Colorretais/patologia , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Ouro/química , Células HT29 , Humanos , Tamanho da Partícula , Relação Estrutura-Atividade , Propriedades de Superfície
7.
Int J Lab Hematol ; 35(6): 580-8, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23551597

RESUMO

INTRODUCTION: The Sysmex XE-5000 is a blood and body fluid analyzer able to differentiate cells into polymorphonuclear, mononuclear, and high-fluorescent cells (HFC). The identity of HFC in cerebrospinal fluid (CSF) has been uncertain; however, compatible with their high nucleic acid content, HFC could represent intrathecal tumor cells. Here, we studied the cellular origin and the diagnostic significance of HFC in CSF. METHODS: Results of CSF examinations with the XE-5000 were analyzed in 65 CSF samples with and 126 CSF samples without tumor cells, as defined by manual microscopy of CSF cytospin preparations. RESULTS: The XE-5000 detected HFC in 51 of 65 tumor cell-positive and in 33 of 126 tumor cell-negative CSF samples (sensitivity: 78.5%, specificity: 73.8%, positive likelihood ratio: 3.0, negative likelihood ratio: 0.29). The percentages of HFC and tumor cells in CSF samples correlated (r² = 0.41, P < 0.0001). Tumor cells escaped detection by the XE-5000 especially in CSF samples with a low percentage of tumor cells. CONCLUSION: While this study identifies tumor cells as the predominant correlate of HFC in CSF, it suggests that measuring HFC is not an appropriate diagnostic test for intrathecal tumor cells. However, if HFC are incidentally detected in CSF, further evaluation by CSF microscopy seems mandatory.


Assuntos
Líquido Cefalorraquidiano/citologia , Citometria de Fluxo/instrumentação , Citometria de Fluxo/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Contagem de Células/instrumentação , Contagem de Células/métodos , Citodiagnóstico/instrumentação , Citodiagnóstico/métodos , Feminino , Humanos , Masculino , Microscopia/métodos , Pessoa de Meia-Idade , Curva ROC , Adulto Jovem
8.
J Biomed Mater Res A ; 89(2): 390-401, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-18563824

RESUMO

Macrophages play a pivotal role in tissue reaction and immune response. They recognize, phagocytose particles and generate cytokines to influence local cellular reactions. Friction and wear of implant components usually generates microparticles (MP) in a size range of 1-10 mum and nanoparticles (NP) in the range of 10-1000 nm. To investigate the possible impact of MP or NP on cellular reactions, we exposed murine macrophages (RAW264.7) to corundum MP and NP. The same mass was used in both NP and MP cell culture solutions, i.e. there were more NP than MP per identical volumes of culture solution. After 4, 24, 48, 72, and 96 h aliquots of cell culture supernatants were tested for different cytokines, growth factors and nitric oxide. Macrophages were stained with MGG (May-Grünwald Giemsa), counted and morphologically characterized by scanning electron microscopy and transmission electron microscopy. Particles were attached to cell surfaces and phagocytosed within cells. Cells stimulated with particles or lipopolysaccharides for positive controls showed surface modifications indicating enhanced function. Although only marginal differences between negative controls and particle-stimulated cells were observed in respect to cytokine production, exposure to corundum particles led to a decrease in the number of vital macrophages and to an increase in the number of giant cells. Corundum NP formed micron-sized aggregates in the cell culture medium and led to the production of more giant cells than MP. Sodiumdodecylsulfate polyacrylamide gel electrophoresis of the cell culture medium with particles proved the adsorption of proteins to particles.


Assuntos
Óxido de Alumínio/química , Óxido de Alumínio/farmacologia , Prótese de Quadril , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Tamanho da Partícula , Adsorção/efeitos dos fármacos , Animais , Contagem de Células , Forma Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Eletroforese em Gel de Poliacrilamida , Amarelo de Eosina-(YS) , Fator Estimulador de Colônias de Granulócitos/metabolismo , Macrófagos/ultraestrutura , Azul de Metileno , Camundongos , Nitritos/metabolismo , Pós
9.
Chest ; 119(5): 1434-8, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11348950

RESUMO

OBJECTIVE: To determine the sensitivity of bacteriologic studies in pediatric pulmonary tuberculosis. PATIENTS AND METHODS: Between January 1988 and December 1996, 104 consecutive patients aged 0 to 18 years received a diagnosis of primary pulmonary tuberculosis at our institution. Demographic, clinical, laboratory, and bacteriologic data were collected. Clinical specimens were studied for acid-fast bacilli detection by Ziehl-Neelsen stain and cultured for Mycobacterium recovery by Lowenstein-Jensen culture medium. Statistical analysis was performed utilizing chi(2), t tests, and multivariate logistic regression analysis. RESULTS: Bacteriologic results were available for 57 patients (54.8%). A positive smear or culture result for Mycobacterium tuberculosis was obtained in 9 of 54 patients (16.6%) and 25 of 50 patients (50%), respectively. Confirmation of M tuberculosis disease was achieved in 28 patients (49.1%). Ziehl-Neelsen stain and Lowenstein-Jensen culture recovery rates were 10.3% (14 of 135) and 52% (48 of 92) of specimens studied, respectively. Sputum, pleural fluid, and biopsy material cultures yielded M tuberculosis in 55%, 75%, and 63% of patients, respectively. Mean +/- SD age (13.7 +/- 4.5 years vs 9.6 +/- 4.5 years) and number of samples submitted for culture (1.93 +/- 0.94 vs 1.31 +/- 0.97) were significantly higher in the confirmed tuberculosis disease group (p < 0.05). The presence of a pleural effusion was also more commonly found in the confirmed tuberculosis disease group (p < 0.05). CONCLUSION: The sensitivity of bacteriologic studies in pediatric pulmonary tuberculosis disease was 49.1%. Age is the main factor associated with the positivity of culture results.


Assuntos
Mycobacterium tuberculosis/efeitos dos fármacos , Tuberculose Pulmonar/microbiologia , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Testes de Sensibilidade Microbiana , Estudos Retrospectivos
11.
J Neuroimaging ; 10(4): 225-8, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11147403

RESUMO

The authors report the findings of multimodal structural, functional, and metabolic imaging in a patient with linear nevus sebaceous syndrome, intractable seizures, and right megalencephaly. Despite nearly continuous paroxysmal electrical activity from the megalencephalic region, imaging studies suggested nonfunctional tissue in this region with reorganization of cortical function to the unaffected ipsilateral hemisphere. Hemispherectomy has been successfully performed in previous patients; however, it could have led to marked left hemiparesis with significant functional morbidity in this patient because of ipsilateral reorganization of the primary motor cortex.


Assuntos
Encefalopatias/diagnóstico , Córtex Cerebral/patologia , Diagnóstico por Imagem , Síndromes Neurocutâneas/diagnóstico , Nevo/diagnóstico , Adulto , Encéfalo/anormalidades , Meios de Contraste , Eletroencefalografia , Epilepsia/diagnóstico , Humanos , Aumento da Imagem , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Masculino , Convulsões/diagnóstico , Tomografia Computadorizada de Emissão , Tomografia Computadorizada de Emissão de Fóton Único
12.
J Hand Surg Br ; 24(6): 724-6, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10672812

RESUMO

The purpose of the present study was to determine whether there is an optimal position for fixation of the one-bone forearm. Eight normal individuals were fitted with a hinged brace which fixed the position of pronation and supination and underwent functional hand testing using the tests of Jebsen et al. Our results indicate that a one-bone forearm in a position of 30 degrees of pronation will provide the best function for writing and working with small objects using the dominant arm.


Assuntos
Braquetes , Rádio (Anatomia)/cirurgia , Ulna/cirurgia , Adulto , Desenho de Equipamento , Antebraço/fisiologia , Mãos/fisiologia , Humanos , Pronação , Supinação
14.
Immunol Today ; 19(3): 133-41, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9540273

RESUMO

Induction of allergic and autoimmune reactions by drugs and other chemicals constitutes a major public health problem. Elucidation of the underlying mechanisms might help improve diagnostic tools and therapeutic approaches. Here, Peter Griem and colleagues focus on several aspects of neoantigen formation by xenobiotics: metabolism of xenobiotics into reactive, haptenic metabolites; polymorphisms of metabolizing enzymes; induction of costimulatory signals; and sensitization of T cells.


Assuntos
Autoimunidade/efeitos dos fármacos , Hipersensibilidade a Drogas/imunologia , Xenobióticos/imunologia , Animais , Exposição Ambiental , Humanos , Modelos Imunológicos , Saúde Pública
15.
Rev Clin Esp ; 196(8): 529-35, 1996 Aug.
Artigo em Espanhol | MEDLINE | ID: mdl-8984539

RESUMO

A study was conducted to investigate the relationships between the characteristics of IgA paraprotein and the clinical findings in a group of 196 patients. In 19 cases IgA paraprotein was associated with another monoclonal immunoglobulin (IgG or IgM); the other 177 patients had a single IgA paraprotein; 145 of them corresponded to multiple myeloma (MM) and the other 32 to other diagnostics. Class and type of paraproteins were identified by immunoelectrophoresis and subclass by an enzyme-immunoassay specifically developed for this study. The degree of polymerization of the protein was determined by gel filtration; quantitation of monoclonal IgA and polyclonal IgG and IgM was obtained by kinetic nephelometry. Out of 196 paraproteins, 96.4% were classified in IgA1 subclass and only 3.6% in IgG2. In 14 cases, all of them diagnosed with MM, monoclonal IgA in serum was associated with Bence-Jones protein; in more than 78% of them light chains corresponded to type lambda, whereas type kappa predominated (over 60%) in cases without Bence-Jones protein in serum. Significantly higher serum levels of monoclonal IgA were associated with the diagnosis of myeloma, with type kappa paraproteins, and with the presence of Bence-Jones protein in serum. The cases with two paraproteins (IgA and IgG or IgM) had significantly lower serum levels of IgA, with comparable levels of total paraprotein (the addition of both monoclonal immunoglobulins). Serum levels of polyclonal IgG and IgM, which appeared decreased in cases of MM, were normal in cases with other conditions. In all these cases, monoclonal IgA showed a monomeric character, whereas relevant amounts of polymerized IgA paraprotein was found in almost a third part of myeloma cases, particularly in those with higher serum levels of paraprotein, or when paraprotein belonged to type kappa. The 5 IgA2 paraproteins analyzed had a polymeric character. In conclusion, a detailed, both qualitative and quantitative, analysis of IgA paraproteins can lead to a better knowledge of conditions associated with their presence and at the same time provides useful data for a clinical evaluation of patients.


Assuntos
Imunoglobulina A/classificação , Mieloma Múltiplo/sangue , Paraproteínas/classificação , Humanos , Imunoglobulina A/sangue , Paraproteínas/análise
16.
Vaccine ; 11(10): 1033-6, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8212823

RESUMO

Of 79 children born to asymptomatic HBsAg chronic carrier mothers and vaccinated at birth against hepatitis B, a total of 71, 66 and 56 could be serologically assessed after 1, 5 and 7 years, respectively. Anti-HBs titres (geometric means) of responders decreased from 2475 to 143 IU l-1 between 1 and 5 years of age and dropped to 82 IU l-1 by 7 years. At this time, a booster dose given to 34 children who showed anti-HBs titres lower or slightly higher than 100 IU l-1 significantly increased titres from 34 to 2985 IU l-1 (p < 0.001). Children whose titres following perinatal vaccination reached 100 to 1000 IU l-1 or above 1000 IU l-1 maintained protective levels (> 10 IU l-1) for 3 and 5 years, respectively. As in adults, anti-HBs titres recorded after the initial vaccination indicate the time at which infants should receive booster vaccination.


Assuntos
Anticorpos Anti-Hepatite B/sangue , Vacinas contra Hepatite B/imunologia , Hepatite B/prevenção & controle , Criança , Pré-Escolar , Seguimentos , Humanos , Esquemas de Imunização , Imunização Secundária , Lactente , Recém-Nascido , Fatores de Tempo , Vacinação
17.
Hepatogastroenterology ; 38(1): 60-3, 1991 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2026391

RESUMO

We present a case of hepatic myelolipoma that was treated by performing a right hepatic lobectomy. These tumors are very uncommon and present great problems for the pre-operative diagnostic evaluation. Currently, the diagnosis is essentially histopathological with a definitive diagnosis being made by immunocytochemical staining. We have found no reports on this type of tumor in the Spanish literature; a review of the published cases confirms our observations and conclusions regarding hepatic myelolipoma.


Assuntos
Lipoma , Neoplasias Hepáticas , Fígado/patologia , Adulto , Humanos , Lipoma/epidemiologia , Lipoma/patologia , Lipoma/cirurgia , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/cirurgia , Masculino , Espanha/epidemiologia
19.
Am J Cardiol ; 52(7): 824-9, 1983 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-6624673

RESUMO

The echocardiographic (echo) features of idiopathic hemochromatosis (IH) were studied in 22 patients. Results were compared with a control group of 22 patients without heart disease. Statistically significant increases in left ventricular (LV) mass, end-diastolic and end-systolic diameters of the left ventricle and in left atrial dimension were observed in patients with IH; significant changes of systolic function indexes (decrease in fractional shortening and ejection fraction and increase in distance of the E point to the septum) were seen as well. These echo abnormalities were mainly seen in patients with abnormal electrocardiograms. In 11 patients with IH, iron removal therapy was carried out by means of periodic phlebotomies. In patients with impaired LV function at the beginning of therapy, comparison between measurements of the initial echo and posttreatment echo showed significant improvement in LV diameters, fractional shortening, ejection fraction, distance from the E point to the septum, LV mass and left atrial dimension.


Assuntos
Cardiomiopatias/terapia , Ecocardiografia , Hemocromatose/terapia , Ferro/sangue , Adulto , Sangria , Cardiomiopatias/sangue , Cardiomiopatias/diagnóstico , Cardiomiopatias/etiologia , Feminino , Hemocromatose/sangue , Hemocromatose/complicações , Hemocromatose/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade
20.
J Prosthet Dent ; 44(3): 338-42, 1980 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-6931227

RESUMO

This study has shown that the polyester urethane elastomers are soft and flexible, characteristics which are desirable for simulating soft facial tissue. In addition, this material was found to have a larger resistance-to-tear when compared with othe materials. The physical and mechanical properties are very sensitive to the composition and the amount of catalyst added. Less influence on the elastomer properties was noticed for the range of temperatures at which it was polymerized. The range of curing time used in this study shows no significant statistical difference on the elastomer properties. Future studies will be directed toward the polymerization of the material at a wider range of times and temperatures to determine the effects at the low and high ends of the range.


Assuntos
Prótese Maxilofacial , Poliuretanos/normas , Fenômenos Químicos , Química , Elasticidade , Dureza , Propriedades de Superfície , Temperatura , Resistência à Tração
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