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1.
Clin Exp Immunol ; 195(3): 395-406, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30368774

RESUMO

Thorough understanding of the complex pathophysiology of osteoarthritis (OA) is necessary in order to open new avenues for treatment. The aim of this study was to characterize the CD4+ T cell population and evaluate their activation and polarization status in OA joints. Fifty-five patients with end-stage knee OA (Kellgren-Lawrence grades III-IV) who underwent surgery for total knee arthroplasty (TKA) were enrolled into this study. Matched samples of synovial membrane (SM), synovial fluid (SF) and peripheral blood (PB) were analysed for CD3+ CD4+ CD8- T cell subsets [T helper type 1 (Th1), Th2, Th17, regulatory T cells] and activation status (CD25, CD69, CD45RO, CD45RA, CD62L) by flow cytometry. Subset-specific cytokines were analysed by cytometric bead array (CBA). SM and SF samples showed a distinct infiltration pattern of CD4+ T cells. In comparison to PB, a higher amount of joint-derived T cells was polarized into CD3+ CD4+ CD8- T cell subsets, with the most significant increase for proinflammatory Th1 cells in SF. CBA analysis revealed significantly increased immunomodulating cytokines [interferon (IFN)-γ, interleukin (IL)-2 and IL-10] in SF compared to PB. Whereas in PB only a small proportion of CD4+ T cells were activated, the majority of joint-derived CD4+ T cells can be characterized as activated effector memory cells (CD69+ CD45RO+ CD62L- ). End-stage OA knees are characterized by an increased CD4+ T cell polarization towards activated Th1 cells and cytokine secretion compared to PB. This local inflammation may contribute to disease aggravation and eventually perpetuate the disease process.


Assuntos
Articulação do Joelho/imunologia , Osteoartrite do Joelho/imunologia , Líquido Sinovial/imunologia , Membrana Sinovial/imunologia , Células Th1/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Polaridade Celular , Citocinas/análise , Feminino , Humanos , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade
2.
J Anim Physiol Anim Nutr (Berl) ; 101(3): 589-604, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27079549

RESUMO

This study examined effects of stage of gestation and nutrient restriction with subsequent realimentation on maternal and foetal bovine pancreatic function. Dietary treatments were assigned on day 30 of pregnancy and included: control (CON; 100% requirements; n = 18) and restricted (R; 60% requirements; n = 30). On day 85, cows were slaughtered (CON, n = 6; R, n = 6), remained on control (CC; n = 12) and restricted (RR; n = 12), or realimented to control (RC; n = 11). On day 140, cows were slaughtered (CC, n = 6; RR, n = 6; RC, n = 5), remained on control (CCC, n = 6; RCC, n = 5) or realimented to control (RRC, n = 6). On day 254, the remaining cows were slaughtered and serum samples were collected from the maternal jugular vein and umbilical cord to determine insulin and glucose concentrations. Pancreases from cows and foetuses were removed, weighed, and subsampled for enzyme and histological analysis. As gestation progressed, maternal pancreatic α-amylase activity decreased and serum insulin concentrations increased (p ≤ 0.03). Foetal pancreatic trypsin activity increased (p < 0.001) with advancing gestation. Foetal pancreases subjected to realimentation (CCC vs. RCC and RRC) had increased protein and α-amylase activity at day 254 (p ≤ 0.02), while trypsin (U/g protein; p = 0.02) demonstrated the opposite effect. No treatment effects were observed for maternal or foetal pancreatic insulin-containing cell clusters. Foetal serum insulin and glucose levels were reduced with advancing gestation (p ≤ 0.03). The largest maternal insulin-containing cell cluster was not influenced by advancing gestation, while foetal clusters grew throughout (p = 0.01). These effects indicate that maternal digestive enzymes are influenced by nutrient restriction and there is a potential for programming of increased foetal digestive enzyme production resulting from previous maternal nutrient restriction.


Assuntos
Glicemia , Privação de Alimentos , Insulina/sangue , Fenômenos Fisiológicos da Nutrição Materna , Pâncreas/enzimologia , Animais , Bovinos , Feminino , Pâncreas/citologia , Pâncreas/metabolismo , Gravidez
3.
Clin Exp Immunol ; 180(1): 143-54, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25393692

RESUMO

It is still controversial which cell types are responsible for synovial inflammation in osteoarthritic (OA) joints. The aim of this study was to quantify the mononuclear cell populations and their cytokines in patients with different knee OA subtypes. Synovial membrane (SM), synovial fluid (SF) and peripheral blood (PB) were harvested from patients with unicompartmental (UC) and bicompartmental (BC) knee OA. Frequencies of mononuclear cells were assessed by flow cytometry in PB and SM. Naive SF samples were analysed for a broad variety of cytokines by multiplex analysis. SM of both groups displayed a distinct mononuclear cell infiltration, with CD14(+) macrophages being the major cell population, followed by CD4(+) T cells and only small numbers of CD8(+) T, CD19(+) B and CD16(+) CD56(+) natural killer (NK) cells. Between the two groups, SM of BC OA showed significantly higher amounts of mononuclear cells (135·7 ± 180 versus 805 ± 675 cells/mg, P = 0·0009) and higher CD4(+) T cell presence (3·4 ± 4·6 versus 9·1 ± 7·5%, P = 0·0267). SF of BC OA displayed significantly higher concentrations for a number of proinflammatory cytokines [CXCL1, eotaxin, interferon (IFN)-γ, interleukin (IL)-7, IL-8, IL-9, IL-12]. UC and BC OA show significant differences in their synovial inflammatory pattern. Whereas in UC OA CD14(+) macrophages are the predominant cell population, BC OA has a higher inflammatory profile and seems to be driven by CD14(+) macrophages and CD4(+) T cells. Inclusion of clinical information into the analysis of cellular and molecular results is pivotal in understanding the pathophysiology of OA.


Assuntos
Citocinas , Articulação do Joelho , Leucócitos Mononucleares , Osteoartrite do Joelho , Líquido Sinovial , Idoso , Idoso de 80 Anos ou mais , Antígenos CD/imunologia , Antígenos CD/metabolismo , Citocinas/imunologia , Citocinas/metabolismo , Feminino , Humanos , Articulação do Joelho/imunologia , Articulação do Joelho/metabolismo , Articulação do Joelho/patologia , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Leucócitos Mononucleares/patologia , Masculino , Pessoa de Meia-Idade , Osteoartrite do Joelho/imunologia , Osteoartrite do Joelho/metabolismo , Osteoartrite do Joelho/patologia , Líquido Sinovial/imunologia , Líquido Sinovial/metabolismo
4.
Orthopade ; 42(8): 643-50, 2013 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-23877660

RESUMO

The use of metal implants has become increasingly more frequent in all fields of medicine throughout the past decades. Numerous studies have demonstrated that metal ions released from these implants can be detected in body fluids remote from the implants. Although diseases directly linked to the release of these ions seem to be rare, the general public is unsettled. In this study we aimed to analyze the impact of molybdenum(V), cobalt(II), chromium(III) and nickel(II) ions on cell surface markers (CD25, CD38, CD69, CD95) and viability (7-AAD/AnnexinV) of human CD4+ T-lymphocytes in vitro. Cobalt(II) ions at a concentration of 1000 µg/l led to a significant suppression of lymphocyte activation markers while nickel(II), chromium(III) and molybdenum(V) did not show any significant impact on these lymphocyte activation markers. Cell viability was significantly reduced by all metal ions, whereas cobalt(II) led to the highest increase of apoptotic cells and was the only metal ion to significantly increase the necrosis rate. While the pathophysiological significance of these findings remains unclear, they are in favour of further research in this field.


Assuntos
Materiais Biocompatíveis/farmacologia , Linfócitos/efeitos dos fármacos , Linfócitos/fisiologia , Metais/farmacologia , Idoso , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Feminino , Humanos , Íons/farmacologia , Linfócitos/citologia , Masculino
5.
Biomaterials ; 268: 120549, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33278685

RESUMO

The recent advances in 3D-printed silicone (PDMS: polydimethylsiloxane) implants present prospects for personalized implants with highly accurate anatomical conformity. However, a potential adverse effect, such as granuloma formation due to immune reactions, still exists. One potential way to overcome this problem is to control the implant/host interface using immunomodulatory coatings. In this study, a new cytokine cocktail composed of interleukin-10 and prostaglandin-E2 was designed to decrease adverse immune reactions and promote tissue integration by fixing macrophages into M2 pro-healing phenotype for an extended period of time. In vitro, the cytokine cocktail maintained low levels of pro-inflammatory cytokine (TNF-α and IL-6) secretions and induced the secretion of IL-10 and the upregulation of multifunctional scavenging and sorting receptor stabilin-1, expressed by M2 macrophages. This cocktail was then loaded in a gelatine-based hydrogel to develop an immunomodulatory material that could be used as a coating for medical devices. The efficacy of this coating was demonstrated in an in vivo rat model during the reconstruction of a tracheal defect by 3D-printed silicone implants. The coating was stable on the silicone implants for over 2 weeks, and the controlled release of the cocktail components was achieved for at least 14 days. In vivo, only 33% of the animals with bare silicone implants survived, whereas 100% of the animals survived with the implant equipped with the immunomodulatory hydrogel. The presence of the hydrogel and the cytokine cocktail diminished the thickness of the inflammatory tissue, the intensity of both acute and chronic inflammation, the overall fibroblastic reaction, the presence of oedema and the formation of fibrinoid (assessed by histology) and led to a 100% survival rate. At the systemic level, the presence of immunomodulatory hydrogels significantly decreased pro-inflammatory cytokines such as TNF-α, IFN-γ, CXCL1 and MCP-1 levels at day 7 and significantly decreased IL-1α, IL-1ß, CXCL1 and MCP-1 levels at day 21. The ability of this new immunomodulatory hydrogel to control the level of inflammation once applied to a 3D-printed silicone implant has been demonstrated. Such thin coatings can be applied to any implants or scaffolds used in tissue engineering to diminish the initial immune response, improve the integration and functionality of these materials and decrease potential complications related to their presence.


Assuntos
Hidrogéis , Silicones , Animais , Imunidade Inata , Impressão Tridimensional , Próteses e Implantes , Ratos
6.
AJNR Am J Neuroradiol ; 42(9): 1584-1590, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34244127

RESUMO

BACKGROUND AND PURPOSE: Our aim was to evaluate an ultrafast 3D-FLAIR sequence using Wave-controlled aliasing in parallel imaging encoding (Wave-FLAIR) compared with standard 3D-FLAIR in the visualization and volumetric estimation of cerebral white matter lesions in a clinical setting. MATERIALS AND METHODS: Forty-two consecutive patients underwent 3T brain MR imaging, including standard 3D-FLAIR (acceleration factor = 2, scan time = 7 minutes 50 seconds) and resolution-matched ultrafast Wave-FLAIR sequences (acceleration factor = 6, scan time = 2 minutes 45 seconds for the 20-channel coil; acceleration factor = 9, scan time = 1 minute 50 seconds for the 32-channel coil) as part of clinical evaluation for demyelinating disease. Automated segmentation of cerebral white matter lesions was performed using the Lesion Segmentation Tool in SPM. Student t tests, intraclass correlation coefficients, relative lesion volume difference, and Dice similarity coefficients were used to compare volumetric measurements among sequences. Two blinded neuroradiologists evaluated the visualization of white matter lesions, artifacts, and overall diagnostic quality using a predefined 5-point scale. RESULTS: Standard and Wave-FLAIR sequences showed excellent agreement of lesion volumes with an intraclass correlation coefficient of 0.99 and mean Dice similarity coefficient of 0.97 (SD, 0.05) (range, 0.84-0.99). Wave-FLAIR was noninferior to standard FLAIR for visualization of lesions and motion. The diagnostic quality for Wave-FLAIR was slightly greater than for standard FLAIR for infratentorial lesions (P < .001), and there were fewer pulsation artifacts on Wave-FLAIR compared with standard FLAIR (P < .001). CONCLUSIONS: Ultrafast Wave-FLAIR provides superior visualization of infratentorial lesions while preserving overall diagnostic quality and yields white matter lesion volumes comparable with those estimated using standard FLAIR. The availability of ultrafast Wave-FLAIR may facilitate the greater use of 3D-FLAIR sequences in the evaluation of patients with suspected demyelinating disease.


Assuntos
Encéfalo , Substância Branca , Artefatos , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Humanos , Imageamento por Ressonância Magnética , Movimento (Física) , Substância Branca/diagnóstico por imagem , Substância Branca/patologia
7.
Prog Urol ; 20(1): 77-9, 2010 Jan.
Artigo em Francês | MEDLINE | ID: mdl-20123532

RESUMO

We report the history of a patient who presented a radiodense large staghorn kidney stone which was investigated by dual energy CT. Dual energy CT showed that this stone consisted of uric and calcic compounds. The patient received a specific treatment combining chemical lysis and lithotripsy active on uric and calcic parts respectively, leading to a complete noninvasive destruction of the stone. It seemed that lithotripsy performed at first step allowed for efficient lysis by chemical agent.


Assuntos
Absorciometria de Fóton , Cálculos Renais/diagnóstico por imagem , Cálculos Renais/terapia , Cálices Renais , Humanos , Masculino , Pessoa de Meia-Idade , Cintilografia
8.
AJNR Am J Neuroradiol ; 41(5): 898-903, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32354710

RESUMO

BACKGROUND AND PURPOSE: Identification of a partial/complete chemotherapy response in pediatric patients with intracranial germ cell tumors is clinically important for radiation treatment and management. Partial/complete response is conventionally determined on postcontrast MR imaging sequences. The purpose of this study was to assess the diagnostic utility of a balanced steady-state free precession sequence as an adjunct to standard MR imaging sequences for the detection of residual tumor in pediatric patients on postchemoreduction pre-radiation planning MR imaging. MATERIALS AND METHODS: This was a retrospective study of pediatric patients with intracranial germ cell tumors undergoing postchemotherapy, preradiotherapy MR imaging. Patients underwent 1.5T or 3T MR imaging with pre- and postcontrast T1WIs, T2WIs, and a balanced steady-state free precession sequence. Two neuroradiologists independently reviewed standard MR imaging sequences without the balanced steady-state free precession sequence, then with the balanced steady-state free precession sequence 1 week later. Assessment for partial/complete response was determined using Response Assessment in Neuro-Oncology criteria. A 5-point Likert scale scored the diagnostic confidence of the neuroradiologist rating each study without/with the balanced steady-state free precession sequence. Rates of residual disease concordance and diagnostic confidence levels without/with the balanced steady-state free precession sequence were calculated. RESULTS: Thirty-nine patients were included with 31 males and 8 females (mean age, 14.15 ± 4.26 years). Thirty-one patients had single-site disease; 8 patients had multisynchronous disease (47 sites in total). Compared to review of the standard MR sequences alone, the addition of the balanced steady state free precession sequence resulted in higher rates of tumor partial response categorization and greater diagnostic confidence levels (P < .001, P < .001). CONCLUSIONS: The balanced steady-state free precession sequence improves detection of residual chemotherapy-reduced intracranial germ cell tumors and increases diagnostic confidence of the neuroradiologist. The balanced steady-state free precession sequence may be an important adjunct to the standard MR imaging protocol for radiation planning.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Interpretação de Imagem Assistida por Computador/métodos , Neoplasia Residual/diagnóstico por imagem , Neoplasias Embrionárias de Células Germinativas/diagnóstico por imagem , Neuroimagem/métodos , Adolescente , Algoritmos , Criança , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Reprodutibilidade dos Testes , Estudos Retrospectivos
9.
AJNR Am J Neuroradiol ; 41(8): 1388-1396, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32732274

RESUMO

BACKGROUND AND PURPOSE: Volumetric brain MR imaging typically has long acquisition times. We sought to evaluate an ultrafast MPRAGE sequence based on Wave-CAIPI (Wave-MPRAGE) compared with standard MPRAGE for evaluation of regional brain tissue volumes. MATERIALS AND METHODS: We performed scan-rescan experiments in 10 healthy volunteers to evaluate the intraindividual variability of the brain volumes measured using the standard and Wave-MPRAGE sequences. We then evaluated 43 consecutive patients undergoing brain MR imaging. Patients underwent 3T brain MR imaging, including a standard MPRAGE sequence (acceleration factor [R] = 2, acquisition time [TA] = 5.2 minutes) and an ultrafast Wave-MPRAGE sequence (R = 9, TA = 1.15 minutes for the 32-channel coil; R = 6, TA = 1.75 minutes for the 20-channel coil). Automated segmentation of regional brain volume was performed. Two radiologists evaluated regional brain atrophy using semiquantitative visual rating scales. RESULTS: The mean absolute symmetrized percent change in the healthy volunteers participating in the scan-rescan experiments was not statistically different in any brain region for both the standard and Wave-MPRAGE sequences. In the patients undergoing evaluation for neurodegenerative disease, the Dice coefficient of similarity between volumetric measurements obtained from standard and Wave-MPRAGE ranged from 0.86 to 0.95. Similarly, for all regions, the absolute symmetrized percent change for brain volume and cortical thickness showed <6% difference between the 2 sequences. In the semiquantitative visual comparison, the differences between the 2 radiologists' scores were not clinically or statistically significant. CONCLUSIONS: Brain volumes estimated using ultrafast Wave-MPRAGE show low intraindividual variability and are comparable with those estimated using standard MPRAGE in patients undergoing clinical evaluation for suspected neurodegenerative disease.


Assuntos
Encéfalo/diagnóstico por imagem , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Doenças Neurodegenerativas/diagnóstico por imagem , Neuroimagem/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Adulto Jovem
10.
Science ; 242(4886): 1624, 1988 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-3201250

RESUMO

Figure 3 (p. 1310) in the report "A 115-kD polypeptide immunologically related to erythrocyte band 3 is present in Golgi membranes" by S. Kellokumpu et al. (2 Dec., p. 1308) was incorrectly printed. The correct figure is reproduced below.


Assuntos
DNA/genética , Hibridização de Ácido Nucleico , Animais , Evolução Biológica , Hominidae/genética , Humanos
11.
Science ; 243(4897): 1485-8, 1989 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-2538921

RESUMO

A true Brønsted analysis of proton transfer in an enzyme mechanism is made possible by the chemical rescue of an inactive mutant of aspartate aminotransferase, where the endogenous general base, Lys258, is replaced with Ala by site-directed mutagenesis. Catalytic activity is restored to this inactive mutant by exogenous amines. The eleven amines studied generate a Brønsted correlation with beta of 0.4 for the transamination of cysteine sulfinate, when steric effects are included in the regression analysis. Localized mutagenesis thus allows the classical Brønsted analysis of transition-state structure to be applied to enzyme-catalyzed reactions.


Assuntos
Aspartato Aminotransferases/metabolismo , Aminas , Sítios de Ligação , Catálise , Escherichia coli/enzimologia , Cinética , Lisina , Mutação , Prótons
12.
Science ; 282(5392): 1321-4, 1998 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-9812897

RESUMO

Glycine receptors are anchored at inhibitory chemical synapses by a cytoplasmic protein, gephyrin. Molecular cloning revealed the similarity of gephyrin to prokaryotic and invertebrate proteins essential for synthesizing a cofactor required for activity of molybdoenzymes. Gene targeting in mice showed that gephyrin is required both for synaptic clustering of glycine receptors in spinal cord and for molybdoenzyme activity in nonneural tissues. The mutant phenotype resembled that of humans with hereditary molybdenum cofactor deficiency and hyperekplexia (a failure of inhibitory neurotransmission), suggesting that gephyrin function may be impaired in both diseases.


Assuntos
Proteínas de Transporte/fisiologia , Coenzimas , Proteínas de Membrana/fisiologia , Metaloproteínas/metabolismo , Molibdênio/metabolismo , Pteridinas/metabolismo , Agregação de Receptores , Receptores de Glicina/fisiologia , Sinapses/fisiologia , Animais , Animais Recém-Nascidos , Encéfalo/citologia , Encéfalo/fisiologia , Quimera , Marcação de Genes , Glicina/fisiologia , Humanos , Camundongos , Cofatores de Molibdênio , Neurônios Motores/fisiologia , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/metabolismo , Fenótipo , Medula Espinal/citologia , Medula Espinal/fisiologia , Células-Tronco , Transmissão Sináptica , Xantina Desidrogenase/metabolismo
13.
Science ; 284(5417): 1161-4, 1999 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-10325225

RESUMO

RAFT1 (rapamycin and FKBP12 target 1; also called FRAP or mTOR) is a member of the ATM (ataxia telangiectasia mutated)-related family of proteins and functions as the in vivo mediator of the effects of the immunosuppressant rapamycin and as an important regulator of messenger RNA translation. In mammalian cells RAFT1 interacted with gephyrin, a widely expressed protein necessary for the clustering of glycine receptors at the cell membrane of neurons. RAFT1 mutants that could not associate with gephyrin failed to signal to downstream molecules, including the p70 ribosomal S6 kinase and the eIF-4E binding protein, 4E-BP1. The interaction with gephyrin ascribes a function to the large amino-terminal region of an ATM-related protein and reveals a role in signal transduction for the clustering protein gephyrin.


Assuntos
Proteínas de Transporte/metabolismo , Proteínas de Membrana/metabolismo , Fosfoproteínas/metabolismo , Fosfotransferases (Aceptor do Grupo Álcool) , Proteínas Quinases S6 Ribossômicas/metabolismo , Transdução de Sinais , Sirolimo/farmacologia , Proteínas Adaptadoras de Transdução de Sinal , Sequência de Aminoácidos , Animais , Proteínas de Transporte/química , Proteínas de Transporte/genética , Proteínas de Ciclo Celular , Linhagem Celular , Membrana Celular/metabolismo , Citoplasma/metabolismo , Expressão Gênica , Células HeLa , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Dados de Sequência Molecular , Mutação , Fosforilação , Ratos , Receptores de Glicina/metabolismo , Proteínas Repressoras/metabolismo , Serina-Treonina Quinases TOR
14.
Sci Rep ; 9(1): 5336, 2019 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-30926846

RESUMO

The particular feature of this study is the investigation of effects of pure fluoride- or stannous ions based mouthrinses on the erosion protective properties and the ultrastructure of the in situ pellicle (12 volunteers). Experimental solutions were prepared either from 500 ppm NaF, SMFP, AmF or SnF2 or 1563 ppm SnCl2, respectively. After 1 min of in situ pellicle formation on bovine enamel slabs, rinses with one of the preparations were performed for 1 min and intraoral specimens' exposure was continued for 28 min. Native enamel slabs and rinses with bidestilled water served as controls. After oral exposure, slabs were incubated in HCl (pH 2; 2.3; 3) for 120 s and kinetics of calcium- and phosphate release were measured photometrically; representative samples were analysed by TEM and EDX. All mouthrinses reduced mineral loss compared to the native 30-min pellicle. The effect was pH-dependent and significant at all pH values only for the tin-containing mouthrinses. No significant differences were observed between the SnF2- and the SnCl2-containing solutions. TEM/EDX confirmed ultrastructural pellicle modifications. SnF2 appears to be the most effective type of fluoride to prevent erosive enamel demineralisation. The observed effects primarily have to be attributed to the stannous ions' content.

15.
AJNR Am J Neuroradiol ; 40(12): 2073-2080, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31727749

RESUMO

BACKGROUND AND PURPOSE: SWI is valuable for characterization of intracranial hemorrhage and mineralization but has long acquisition times. We compared a highly accelerated wave-controlled aliasing in parallel imaging (CAIPI) SWI sequence with 2 commonly used alternatives, standard SWI and T2*-weighted gradient recalled-echo (T2*W GRE), for routine clinical brain imaging at 3T. MATERIALS AND METHODS: A total of 246 consecutive adult patients were prospectively evaluated using a conventional SWI or T2*W GRE sequence and an optimized wave-CAIPI SWI sequence, which was 3-5 times faster than the standard sequence. Two blinded radiologists scored each sequence for the presence of hemorrhage, the number of microhemorrhages, and severity of motion artifacts. Wave-CAIPI SWI was then evaluated in head-to-head comparison with the conventional sequences for visualization of pathology, artifacts, and overall diagnostic quality. Forced-choice comparisons were used for all scores. Wave-CAIPI SWI was tested for superiority relative to T2*W GRE and for noninferiority relative to standard SWI using a 15% noninferiority margin. RESULTS: Compared with T2*W GRE, wave-CAIPI SWI detected hemorrhages in more cases (P < .001) and detected more microhemorrhages (P < .001). Wave-CAIPI SWI was superior to T2*W GRE for visualization of pathology, artifacts, and overall diagnostic quality (all P < .001). Compared with standard SWI, wave-CAIPI SWI showed no difference in the presence or number of hemorrhages identified. Wave-CAIPI SWI was noninferior to standard SWI for the visualization of pathology (P < .001), artifacts (P < .01), and overall diagnostic quality (P < .01). Motion was less severe with wave-CAIPI SWI than with standard SWI (P < .01). CONCLUSIONS: Wave-CAIPI SWI provided superior visualization of pathology and overall diagnostic quality compared with T2*W GRE and was noninferior to standard SWI with reduced scan times and reduced motion artifacts.


Assuntos
Encéfalo/diagnóstico por imagem , Hemorragias Intracranianas/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Neuroimagem/métodos , Adulto , Idoso , Artefatos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
16.
Neuron ; 15(3): 563-72, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7546736

RESUMO

The tubulin-binding protein gephyrin copurifies with the inhibitory glycine receptor (GlyR) and is essential for its postsynaptic localization. Here we have analyzed the interaction between the GlyR and recombinant gephyrin and identified a gephyrin binding site in the cytoplasmic loop between the third and fourth transmembrane segments of the beta subunit. GlyR alpha subunits and GABAA receptor proteins failed to bind recombinant gephyrin. However, insertion of an 18 residue segment of the GlyR beta subunit into the GABAA receptor beta 1 subunit conferred gephyrin binding both in an overlay assay and in transfected mammalian cells. These results indicate that beta subunit expression is essential for the formation of a postsynaptic GlyR matrix.


Assuntos
Proteínas de Transporte/metabolismo , Proteínas de Membrana/metabolismo , Receptores de Glicina/química , Sequência de Aminoácidos , Sequência de Bases , Sítios de Ligação , Linhagem Celular , Eletroforese em Gel de Poliacrilamida , Embrião de Mamíferos , Expressão Gênica , Humanos , Rim , Substâncias Macromoleculares , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Receptores de GABA/genética , Receptores de GABA/metabolismo , Receptores de Glicina/genética , Receptores de Glicina/metabolismo , Proteínas Recombinantes/metabolismo , Homologia de Sequência , Transfecção
17.
Neuron ; 8(6): 1161-70, 1992 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1319186

RESUMO

A 93 kd polypeptide associated with the mammalian inhibitory glycine receptor (GlyR) is localized at central synapses and binds with high affinity to polymerized tubulin. This protein, named gephyrin (from the Greek gamma epsilon phi upsilon rho alpha, bridge), is thought to anchor the GlyR to subsynaptic microtubules. Here we report its primary structure deduced from cDNA and show that corresponding transcripts are found in all rat tissues examined. In brain, at least five different gephyrin mRNAs are generated by alternative splicing. Expression of gephyrin cDNAs in 293 kidney cells yields polypeptides reactive with a gephyrin-specific antibody, which coprecipitate with polymerized tubulin. Thus, gephyrin may define a novel type of microtubule-associated protein involved in membrane protein-cytoskeleton interactions.


Assuntos
Proteínas de Transporte/genética , DNA Recombinante , Variação Genética , Proteínas de Membrana/genética , Receptores de Neurotransmissores/metabolismo , Tubulina (Proteína)/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Proteínas de Transporte/química , Proteínas de Transporte/metabolismo , Linhagem Celular , DNA/isolamento & purificação , Rim/citologia , Rim/metabolismo , Proteínas de Membrana/química , Proteínas de Membrana/metabolismo , Dados de Sequência Molecular , Sondas de Oligonucleotídeos/genética , Splicing de RNA , RNA Mensageiro/genética , Ratos , Receptores de Glicina , Homologia de Sequência do Ácido Nucleico , Transcrição Gênica
18.
Nat Neurosci ; 3(1): 22-9, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10607391

RESUMO

The formation of postsynaptic GABAA and glycine receptor clusters requires the receptor-associated peripheral membrane protein gephyrin. Here we describe two splice variants of a novel gephyrin-binding protein, termed collybistin I and II, which belong to the family of dbl-like GDP/GTP exchange factors (GEFs). Co-expression of collybistin II with gephyrin induced the formation of submembrane gephyrin aggregates that accumulate hetero-oligomeric glycine receptors. Our data suggest that collybistin II regulates the membrane deposition of gephyrin by activating a GTPase of the Rho/Rac family. Therefore, this protein may be an important determinant of inhibitory postsynaptic membrane formation and plasticity.


Assuntos
Encéfalo/metabolismo , Proteínas de Transporte/metabolismo , Fatores de Troca do Nucleotídeo Guanina/fisiologia , Proteínas de Membrana/metabolismo , Membranas Sinápticas/metabolismo , Processamento Alternativo , Sequência de Aminoácidos , Animais , Sequência de Bases , Linhagem Celular , Sequência Conservada , GTP Fosfo-Hidrolases/metabolismo , Fatores de Troca do Nucleotídeo Guanina/genética , Humanos , Substâncias Macromoleculares , Dados de Sequência Molecular , Especificidade de Órgãos , Isoformas de Proteínas/metabolismo , Isoformas de Proteínas/fisiologia , Ratos , Receptores de Glicina/metabolismo , Fatores de Troca de Nucleotídeo Guanina Rho , Homologia de Sequência de Aminoácidos , Sinapses/metabolismo , Domínios de Homologia de src
19.
Prog Urol ; 18(9): 562-5, 2008 Oct.
Artigo em Francês | MEDLINE | ID: mdl-18986626

RESUMO

The prospect for a treatment by chemical lysis and the effective disease prevention appropriateness are the purposes of the early recognition of the uric acid stones, which counts up to 10% of all kidney stones. Until now, this characterization was possible only afterwards by the chemical analysis of an expelled stone. Neither biology nor radiology contributed as a valid share on this subject. CT with "dual energy" mode seems to fill this gap. This concept, known since the seventies, reaches the clinical routine now thanks for the use of a "dual source CT".


Assuntos
Absorciometria de Fóton , Cálculos Renais/diagnóstico , Tomografia Computadorizada por Raios X , Ácido Úrico , Humanos , Cálculos Renais/química , Ácido Úrico/análise
20.
Space Sci Rev ; 214(1)2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-30713357

RESUMO

OSIRIS-REx will return pristine samples of carbonaceous asteroid Bennu. This article describes how pristine was defined based on expectations of Bennu and on a realistic understanding of what is achievable with a constrained schedule and budget, and how that definition flowed to requirements and implementation. To return a pristine sample, the OSIRIS-REx spacecraft sampling hardware was maintained at level 100 A/2 and <180 ng/cm2 of amino acids and hydrazine on the sampler head through precision cleaning, control of materials, and vigilance. Contamination is further characterized via witness material exposed to the spacecraft assembly and testing environment as well as in space. This characterization provided knowledge of the expected background and will be used in conjunction with archived spacecraft components for comparison with the samples when they are delivered to Earth for analysis. Most of all, the cleanliness of the OSIRIS-REx spacecraft was achieved through communication among scientists, engineers, managers, and technicians.

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