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1.
Sci Rep ; 12(1): 486, 2022 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-35017565

RESUMO

Uropathogenic Escherichia coli (UPEC) may undergo a cyclic cascade of morphological alterations that are believed to enhance the potential of UPEC to evade host responses and re-infect host cell. However, knowledge on the pathogenic potential and host activation properties of UPEC during the morphological switch is limited. Microarray analysis was performed on mRNA isolated from human bladder epithelial cells (HBEP) after exposure to three different morphological states of UPEC (normal coliform, filamentous form and reverted form). Cells stimulated with filamentous bacteria showed the lowest number of significant gene alterations, although the number of enriched gene ontology classes was high suggesting diverse effects on many different classes of host genes. The normal coliform was in general superior in stimulating transcriptional activity in HBEP cells compared to the filamentous and reverted form. Top-scored gene entities activated by all three morphological states included IL17C, TNFAIP6, TNF, IL20, CXCL2, CXCL3, IL6 and CXCL8. The number of significantly changed canonical pathways was lower in HBEP cells stimulated with the reverted form (32 pathways), than in cells stimulated with the coliform (83 pathways) or filamentous bacteria (138 pathways). A host cell invasion assay showed that filamentous bacteria were unable to invade bladder cells, and that the number of intracellular bacteria was markedly lower in cells infected with the reverted form compared to the coliform. In conclusion, the morphological state of UPEC has major impact on the host bladder response both when evaluating the number and the identity of altered host genes and pathways.


Assuntos
Células Epiteliais/metabolismo , Infecções por Escherichia coli/genética , Transcrição Gênica , Bexiga Urinária/microbiologia , Escherichia coli Uropatogênica/fisiologia , Moléculas de Adesão Celular/genética , Moléculas de Adesão Celular/metabolismo , Linhagem Celular , Quimiocina CXCL2/genética , Quimiocina CXCL2/metabolismo , Quimiocinas CXC/genética , Quimiocinas CXC/metabolismo , Células Epiteliais/microbiologia , Infecções por Escherichia coli/metabolismo , Infecções por Escherichia coli/microbiologia , Humanos , Interleucina-6/genética , Interleucina-6/metabolismo , Bexiga Urinária/metabolismo , Escherichia coli Uropatogênica/crescimento & desenvolvimento
2.
Clin Otolaryngol ; 45(5): 667-680, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32386454

RESUMO

BACKGROUND: Bone-anchored hearing systems (BAHSs) are widely used for hearing rehabilitation and are indicated in cases of conductive and mixed hearing loss and in single-sided deafness. The Ponto system, that is one available option, has been on the market since 2009. OBJECTIVE OF REVIEW: The aim of this study is to systematically review the literature reporting on the Ponto system, with regard to audiological and surgical outcomes and patient's quality-of-life scores. TYPE OF REVIEW: A systematic literature search was performed in the PubMed database 2009-July 2019. SEARCH STRATEGY: Search term: ((osseointegrated hearing aid) OR (bone conduction implant) OR (bone anchored hearing) OR BAHA OR BAHS OR BAHI). Pre-defined inclusion and exclusion criteria were applied. EVALUATION METHOD: English-language articles reporting original clinical data (audiological, surgical or quality-of-life outcomes) on the Ponto system were included. Articles reporting on Ponto and another BAHS system where the results on Ponto constituted less than 50% of the patient population or including only results on testband or softband devices were excluded. RESULTS: Audiological outcomes were discussed in 20 publications. Improvement against the unaided thresholds was demonstrated. The functional improvement was on average 33.9 dB. The effective gain or remaining air-bone gap was on average 6.7 dB. All evaluated data showed aided speech reception thresholds significantly below normal speech level. Twenty-seven publications reported surgical and follow-up data for the Ponto system. Implant survival was 97.7%, adverse skin reactions (Holgers ≥ 2) were 5% across visits and 15% across patients. No complications were life-threatening, causing permanent disability/damage or requiring a hospitalisation. Five studies reported quality of life using the Glasgow benefit inventory, 98% reported an improvement when analysing the score on an individual level. CONCLUSIONS: The outcomes of this systematic review confirm that percutaneous systems provide consistent audiological benefits and improved quality of life for patients. Further, the review demonstrates that the percutaneous systems are safe, with relatively low complication rates. Skin-related complications are the most common complication type and are experienced by approximately one patient out of seven, or in less than one of 20 follow-up visits.


Assuntos
Condução Óssea/fisiologia , Previsões , Auxiliares de Audição , Perda Auditiva Condutiva-Neurossensorial Mista/cirurgia , Audição/fisiologia , Âncoras de Sutura , Desenho de Equipamento , Seguimentos , Perda Auditiva Condutiva-Neurossensorial Mista/fisiopatologia , Humanos , Qualidade de Vida
3.
Front Microbiol ; 8: 1058, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28659883

RESUMO

It is known that an ineffective antibiotic treatment can induce morphological shifts in uropathogenic Escherichia coli (UPEC) but the virulence properties during these shifts remain to be studied. The present study examines changes in global gene expression patterns and in virulence factor-associated genes in an extended spectrum beta-lactamase (ESBL)-producing UPEC (ESBL019) during the morphologic transitions induced by an ineffective antibiotic and in the presence of human primary bladder epithelial cells. Microarray results showed that the different morphological states of ESBL019 had significant transcriptional alterations of a large number of genes (Transition; 7%, Filamentation; 32%, and Reverted 19% of the entities on the array). All three morphological states of ESBL019 were associated with a decreased energy metabolism, altered iron acquisition systems and altered adhesion expression. In addition, genes associated with LPS synthesis and bacterial motility was also altered in all the morphological states. Furthermore, the transition state induced a significantly higher release of TNF-α from bladder epithelial cells compared to all other morphologies, while the reverted state was unable to induce TNF-α release. Our findings show that the morphological shifts induced by ineffective antibiotics are associated with significant transcriptional virulence alterations in ESBL-producing UPEC, which may affect survival and persistence in the urinary tract.

4.
Biochemistry ; 46(33): 9432-42, 2007 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-17655280

RESUMO

The physiological roles of immunophilins are unclear, but many possess peptidyl-prolyl isomerase (PPIase) activity, and they have been found in all organisms examined to date, implying that they are involved in fundamental, protein-folding processes. The chloroplast thylakoid lumen of the higher plant Arabidopsis thaliana contains up to 16 immunophilins (five cyclophilins and 11 FKBPs), but only two of them, AtCYP20-2 and AtFKBP13, have been found to be active PPIases, indicating that the other immunophilins in this cellular compartment may have lost their putative PPIase activities. To assess this possibility, we characterized two independent Arabidopsis knockout lines lacking AtCYP20-2 in enzymological and quantitative proteomic analyses. The PPIase activity in thylakoid lumen preparations of both mutants was equal to that of corresponding wild-type preparations, and comparative two-dimensional difference gel electrophoresis analyses of the lumenal proteins of the mutants and wild type showed that none of the potential PPIases was more abundant in the AtCYP20-2 deficient plants. Enzymatic analyses established that all PPIase activity in the mutant thylakoid lumen was attributable to AtFKBP13, and oxidative activation of this enzyme compensated for the lack of AtCYP20-2. Accordingly, sequence analyses of the potential catalytic domains of lumenal cyclophilins and FKBPs demonstrated that only AtCYP20-2 and AtFKBP13 possess all of the amino acid residues found to be essential for PPIase activity in earlier studies of human cyclophilin A and FKBP12. Thus, none of the immunophilins in the chloroplast thylakoid lumen of Arabidopsis except AtCYP20-2 and AtFKBP13 appear to possess prolyl isomerase activity toward peptide substrates.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/enzimologia , Imunofilinas/metabolismo , Peptidilprolil Isomerase/metabolismo , Proteínas de Ligação a Tacrolimo/metabolismo , Tilacoides/enzimologia , Sequência de Aminoácidos , Arabidopsis/genética , Proteínas de Arabidopsis/análise , Proteínas de Arabidopsis/genética , Ciclofilinas/genética , Ciclofilinas/metabolismo , Genômica , Imunofilinas/análise , Imunofilinas/genética , Dados de Sequência Molecular , Mutação , Peptidilprolil Isomerase/análise , Peptidilprolil Isomerase/genética , Proteômica , Especificidade por Substrato , Proteínas de Ligação a Tacrolimo/análise
5.
Clin Implant Dent Relat Res ; 8(4): 223-32, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17100748

RESUMO

BACKGROUND: The current investigation focuses on new implant designs for increased predictability in clinically demanding situations. Microtextured implant surfaces create favorable conditions for enhanced osseointegration of dental implants compared to implants with a smooth surface, and the macroscopic implant design may influence implant stability. PURPOSE: The aim of the present study was to retrospectively evaluate the clinical performance of a novel implant design in the rehabilitation of completely edentulous jaws and in combination with an immediate function protocol. MATERIALS AND METHODS: Forty-six consecutive patients received 189 study implants (NobelSpeedy concept implant, Nobel Biocare AB, Göteborg, Sweden) supporting 53 full-arch all-acrylic prostheses (44 maxilla, 9 mandible). The majority (66%) of the reconstructions were supported by four implants, of which the two posterior implants were tilted. All patients were followed for a minimum of 1 year. Radiographic assessment of the marginal bone level was performed. RESULTS: Two implants were lost in two patients, rendering a 1-year cumulative clinical survival rate of 98.9%. The marginal bone level was, on average, situated 1.2 +/- 0.7 mm below the implant-abutment interface after 1 year of loading. Good soft tissue health and overall esthetic outcome was reported. CONCLUSIONS: The results of the present pilot study indicate that fully edentulous jaws with various types of bone can be treated with high success and good esthetics using immediately loaded implants with the presented design, and that favorable marginal bone levels can be maintained.


Assuntos
Implantação Dentária Endóssea , Implantes Dentários , Planejamento de Prótese Dentária , Prótese Dentária Fixada por Implante , Prótese Total Imediata , Boca Edêntula/reabilitação , Adulto , Idoso , Densidade Óssea , Materiais Revestidos Biocompatíveis , Implantação Dentária Endóssea/métodos , Falha de Restauração Dentária , Análise do Estresse Dentário , Feminino , Humanos , Tábuas de Vida , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Retrospectivos , Propriedades de Superfície , Titânio
6.
FEBS Lett ; 580(26): 6055-61, 2006 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-17054949

RESUMO

Peroxiredoxins have been discovered in many organisms ranging from eubacteria to mammals, and their known biological functions include both oxidant defense and signal transduction. The genome of Arabidopsis thaliana encodes for ten individual peroxiredoxins, of which four are located in the chloroplast. The best-characterized member of the chloroplast peroxiredoxins is 2-Cys Prx that is associated with the stroma side of the thylakoid membrane and is considered to participate in antioxidant defense and protection of photosynthesis. This study addressed the chloroplast peroxiredoxin Prx Q and showed that its subcellular location is the lumen of the thylakoid membrane. To get insight in the biological function of the Prx Q protein of Arabidopsis, the protein levels of the Prx Q protein in thylakoid membranes were studied under different light conditions and oxidative stress. A T-DNA knockout mutant of Prx Q did not show any visible phenotype and had normal photosynthetic performance with a slightly increased oxygen evolving activity.


Assuntos
Cloroplastos/química , Peroxidases/análise , Proteoma , Proteínas de Arabidopsis , Cloroplastos/metabolismo , Luz , Estresse Oxidativo , Oxigênio/metabolismo , Peroxidases/genética , Peroxidases/fisiologia , Peroxirredoxinas , Tilacoides/química
7.
Biochim Biophys Acta ; 1763(10): 1031-9, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17005269

RESUMO

Endochondral bone formation is orchestrated by mesenchymal cell condensation to form cartilage anlagen, which act as a template for bone formation and eventual mineralization. The current study performed gene expression analysis to examine pre- and post-mineralization stages (E15 and E19) of endochondral bone formation, using fetal metatarsal long bones as a model. An extensive number of genes were differentially expressed, with 543 transcripts found to have at least 2-fold up-regulation and 742 with a greater than 2-fold down-regulation. A bioinformatics approach was adopted based on gene ontology groups, and this identified genes associated with the regulation of signaling and skeletal development, cartilage replacement by bone, and matrix degradation and turnover. Transcripts linked to skeletal patterning, including Hoxd genes 10-12, Gli2 and Noggin were considerably down-regulated at E19. Whereas genes associated with bone matrix formation and turnover, ACP5, MMP-13, bone sialoprotein, osteopontin, dentin matrix protein-1 and MMP-9 all were distinctly up-regulated at this later time point. This approach to studying the formation of the primary ossification center provides a unique picture of the developmental dynamics involved in the molecular and biochemical processes during this intricately regulated process.


Assuntos
Calcificação Fisiológica/genética , Cartilagem/metabolismo , Matriz Extracelular/metabolismo , Ossos do Metatarso/embriologia , Ossos do Metatarso/metabolismo , Osteogênese/genética , Animais , Cartilagem/embriologia , Análise por Conglomerados , Espaço Extracelular/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Ossos do Metatarso/ultraestrutura , Camundongos , Modelos Biológicos , Análise de Sequência com Séries de Oligonucleotídeos
8.
Bone ; 34(6): 949-60, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15193541

RESUMO

Nucleobindin (Nuc), also known as CALNUC, is a Ca(2+)-binding protein, located in the nucleus, the Golgi apparatus and the endoplasmic reticulum (ER). The presence of a signal sequence in Nuc suggests secretion from the cell and it has been found in bone extracellular matrix. Within the present study, molecular biological and morphological methods were combined to evaluate the synthesis and distribution of Nuc in and around cells of rat metaphyseal and calvarial bone. Northern blot analysis and in situ hybridization of bone tissues confirmed that the protein was a product of bone cells. By electron microscopy, immunolabeling for Nuc was seen in osteoid of newly formed bone, on all surfaces facing the various bone cells and also in compact bone. Intracellularly, the gold particles were found in the rough ER of osteoblasts, which suggested synthesis of the protein by these cells. Compared to bone sialoprotein and osteopontin, Nuc demonstrated different localization pattern in bone trabeculae, with the majority of labeling restricted to nonmineralized osteoid. Moreover, the role of Nuc during the mineralization process was investigated in rat calvaria-derived primary osteoblasts grown under osteogenic conditions. Semiquantitative RT-PCR and Northern blot analysis showed Nuc expression to be low during cell proliferation, upregulated during differentiation and matrix maturation, but subsequently downregulated during mineralization. In summary, our data show that Nuc was synthesized by osteoblasts and osteocytes, and secreted into the osteoid, suggesting a role as a modulator of matrix maturation in the mineralization process in bone.


Assuntos
Matriz Óssea/metabolismo , Proteínas de Ligação a DNA/biossíntese , Osteócitos/metabolismo , Osteogênese/fisiologia , Animais , Matriz Óssea/ultraestrutura , Proteínas de Ligação ao Cálcio , Células Cultivadas , Proteínas de Ligação a DNA/metabolismo , Fêmur/metabolismo , Fêmur/ultraestrutura , Proteínas do Tecido Nervoso , Nucleobindinas , Osteócitos/ultraestrutura , Ratos , Ratos Sprague-Dawley , Crânio/metabolismo , Crânio/ultraestrutura
9.
Matrix Biol ; 22(2): 179-91, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12782144

RESUMO

Previous studies have reported that calreticulin (CRT), a calcium-binding and chaperoning protein, is expressed only in the endoplasmatic reticulum, nucleus and at the cell surface. In this study we clearly show that odontoblasts and predentin matrix contain CRT. To our knowledge, this is the first time CRT has been described in the extracellular matrix. The expression of CRT was studied by immunohistochemistry, ultrastructural immunocytochemistry and in situ hybridization in developing rat teeth. CRT was detected as a 59-kDa protein in rat pulp cell culture medium and dentin extracellular matrix extract by Western blotting. The presence of the protein was shown in rat odontoblasts and predentin with immunohistochemistry. At the ultrastructural level, the labeling was distributed in the rat odontoblasts, ameloblasts and predentin. Northern blotting showed the presence of CRT mRNA in rat molars, which was confirmed by in situ hybridization in odontoblasts and ameloblasts. We now present the first convincing evidence that CRT is found in extracellular matrix where it may play an important role in mineralization.


Assuntos
Proteínas de Ligação ao Cálcio/metabolismo , Calreticulina/metabolismo , Retículo Endoplasmático/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Ameloblastos/metabolismo , Animais , Animais Recém-Nascidos/metabolismo , Northern Blotting , Western Blotting , Osso e Ossos/metabolismo , Calreticulina/genética , Calreticulina/isolamento & purificação , Bovinos , Células Cultivadas , Meios de Cultivo Condicionados/metabolismo , Polpa Dentária/citologia , Polpa Dentária/metabolismo , Dentina/metabolismo , Matriz Extracelular/metabolismo , Imuno-Histoquímica , Incisivo/metabolismo , Incisivo/ultraestrutura , Maxila , Dente Molar/metabolismo , Odontoblastos/metabolismo , Osteoblastos/metabolismo , RNA Mensageiro/metabolismo , Ratos , Vitamina D/farmacologia
10.
Eur J Oral Sci ; 111(2): 128-36, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12648264

RESUMO

Osteoadherin (OSAD) is a keratan sulfate-containing proteoglycan, belonging to the small leucine-rich proteoglycan (SLRP) family. In bone OSAD has been localized in primary spongiosa within the bovine fetal rib growth plate. Moreover, in situ hybridization has shown expression of OSAD in osteoblasts close to the cartilage and bone border in the growth plate of rat femur. mRNA expression has also detected OSAD in mature osteoblasts on the surface of bone trabeculae. We have identified OSAD in extracts of bovine dentin, and the identity was verified by N-terminal sequencing. Western blot analysis detected two bands in bovine bone and dentin at 85 kDa and 60 kDa. Northern blot analysis of RNA samples from 5-d-old-rat tooth and femur showed a 1.9-kb transcript for OSAD in both tissues. OSAD was located to the mineralized dentin matrix, cementum and surrounding alveolar bone by immunohistochemistry, and in situ hybridization showed OSAD to be highly expressed during early crown formation in the entire odontoblast cell layer, in the area of Hertwig's epithelial root sheath, in the cells of the newly formed mantle dentin, and in the odontoblasts at the fissures. Ultrastructural studies indicated that OSAD might be associated with collagen fibrils. Thus, OSAD may play an important role during tooth development and biomineralization of dentin.


Assuntos
Cemento Dentário/metabolismo , Dentina/metabolismo , Proteínas da Matriz Extracelular/biossíntese , Odontoblastos/metabolismo , Odontogênese , Proteoglicanas/biossíntese , Processo Alveolar/química , Processo Alveolar/metabolismo , Sequência de Aminoácidos , Animais , Northern Blotting , Calcificação Fisiológica , Bovinos , Cemento Dentário/química , Dentina/química , Eletroforese em Gel de Poliacrilamida , Proteínas da Matriz Extracelular/análise , Imuno-Histoquímica , Hibridização In Situ , Técnicas de Sonda Molecular , Odontoblastos/química , Odontoblastos/ultraestrutura , Proteoglicanas/análise , Ratos , Ratos Sprague-Dawley
11.
J Biol Chem ; 277(10): 8354-65, 2002 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-11719511

RESUMO

The thylakoid membrane of the chloroplast is the center of oxygenic photosynthesis. To better understand the function of the luminal compartment within the thylakoid network, we have carried out a systematic characterization of the luminal thylakoid proteins from the model organism Arabidopsis thaliana. Our data show that the thylakoid lumen has its own specific proteome, of which 36 proteins were identified. Besides a large group of peptidyl-prolyl cis-trans isomerases and proteases, a family of novel PsbP domain proteins was found. An analysis of the luminal signal peptides showed that 19 of 36 luminal precursors were marked by a twin-arginine motif for import via the Tat pathway. To compare the model organism Arabidopsis with another typical higher plant, we investigated the proteome from the thylakoid lumen of spinach and found that the luminal proteins from both plants corresponded well. As a complement to our experimental investigation, we made a theoretical prediction of the luminal proteins from the whole Arabidopsis genome and estimated that the thylakoid lumen of the chloroplast contains approximately 80 proteins.


Assuntos
Arabidopsis/química , Arabidopsis/fisiologia , Cloroplastos/química , Tilacoides/química , Motivos de Aminoácidos , Sequência de Aminoácidos , Divisão Celular , Eletroforese em Gel Bidimensional , Genoma de Planta , Dados de Sequência Molecular , Fenômenos Fisiológicos Vegetais , Ligação Proteica , Estrutura Terciária de Proteína , Coloração pela Prata , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Spinacia oleracea
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