Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 13 de 13
Filtrar
1.
Langmuir ; 37(30): 9069-9077, 2021 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-34288683

RESUMO

Thermodynamic and structural properties of the N-alkanoyl-substituted α-amino acids threonine and serine, differing only by one CH3 group in the head group, are determined and compared. Detailed characterization of the influence of stereochemistry proves that all enantiomers form an oblique monolayer lattice structure whereas the corresponding racemates build orthorhombic lattice structures due to dominating heterochiral interactions, except N-C16-dl-serine-ME as first example of dominating homochiral interactions in a racemic mixture of N-alkanoyl-substituted α-amino acids. In all cases, the liquid expanded-liquid condensed (LE/LC) transition pressure of the racemic mixtures is above that of the corresponding enantiomers. Phase diagrams are proposed. Using the program Hardpack to predict tilt angles and cross-sectional area of the alkyl chains shows reasonable agreement with the experimental grazing incidence X-ray diffraction (GIXD) data.


Assuntos
Treonina , Água , Serina , Termodinâmica , Difração de Raios X
2.
Cell Death Dis ; 13(11): 975, 2022 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-36402750

RESUMO

Muscle repair in dysferlinopathies is defective. Although macrophage (Mø)-rich infiltrates are prominent in damaged skeletal muscles of patients with dysferlinopathy, the contribution of the immune system to the disease pathology remains to be fully explored. Numbers of both pro-inflammatory M1 Mø and effector T cells are increased in muscle of dysferlin-deficient BlAJ mice. In addition, symptomatic BlAJ mice have increased muscle production of immunoproteasome. In vitro analyses using bone marrow-derived Mø of BlAJ mice show that immunoproteasome inhibition results in C3aR1 and C5aR1 downregulation and upregulation of M2-associated signaling. Administration of immunoproteasome inhibitor ONX-0914 to BlAJ mice rescues muscle function by reducing muscle infiltrates and fibro-adipogenesis. These findings reveal an important role of immunoproteasome in the progression of muscular dystrophy in BlAJ mouse and suggest that inhibition of immunoproteasome may produce therapeutic benefit in dysferlinopathy.


Assuntos
Músculo Esquelético , Distrofia Muscular do Cíngulo dos Membros , Camundongos , Animais , Disferlina/genética , Músculo Esquelético/patologia , Distrofia Muscular do Cíngulo dos Membros/tratamento farmacológico , Distrofia Muscular do Cíngulo dos Membros/genética , Distrofia Muscular do Cíngulo dos Membros/patologia , Imunidade Inata
3.
Sci Rep ; 8(1): 14241, 2018 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-30250234

RESUMO

Nucleotide-binding Oligomerization Domain-2 (NOD2) mutations are associated with an increased risk to develop Crohn's Disease. In previous studies, we have shown that Nod2-/- mice manifest increased proportion of Lamina Propria (LP) CD4+ LAP+ Foxp3- regulatory cells, when compared with Nod2+/+ mice, while CD4+ Foxp3 + regulatory cells were not affected. Here, we investigated the Nod2 gut microbiota, by 16S rRNA pyrosequencing, at steady state and after TNBS-colitis induction in mice reared separately or in cohousing, correlating the microbial profiles with LP regulatory T cells proportion and tissue cytokines content. We found that enrichment of Rikenella and Alistipes (Rikenellaceae) in Nod2-/- mice at 8 weeks of age reared separately was associated with increased proportion of CD4+ LAP+ Foxp3- cells and less severe TNBS-colitis. In co-housed mice the acquisition of Rickenellaceae by Nod2+/+ mice was associated with increased CD4+ LAP+ Foxp3- proportion and less severe colitis. Severe colitis was associated with enrichment of gram-negative pathobionts (Escherichia and Enterococcus), while less severe colitis with protective bacteria (Barnesiella, Odoribacter and Clostridium IV). Environmental factors acting on genetic background with different outcomes according to their impact on microbiota, predispose in different ways to inflammation. These results open a new scenario for therapeutic attempt to re-establish eubiosis in Inflammatory Bowel Disease patients with NOD2 polymorphisms.


Assuntos
Colite/microbiologia , Doença de Crohn/microbiologia , Inflamação/microbiologia , Proteína Adaptadora de Sinalização NOD2/genética , Animais , Linfócitos T CD4-Positivos/microbiologia , Clostridium/genética , Clostridium/patogenicidade , Colite/genética , Colite/patologia , Doença de Crohn/genética , Doença de Crohn/patologia , Citocinas/genética , Modelos Animais de Doenças , Enterococcus/genética , Enterococcus/patogenicidade , Escherichia/genética , Escherichia/patogenicidade , Fatores de Transcrição Forkhead/genética , Microbioma Gastrointestinal/genética , Humanos , Inflamação/genética , Inflamação/patologia , Mucosa Intestinal/microbiologia , Mucosa Intestinal/patologia , Camundongos , RNA Ribossômico 16S/genética , Linfócitos T Reguladores/metabolismo , Linfócitos T Reguladores/patologia
4.
Phys Rev E Stat Nonlin Soft Matter Phys ; 68(6 Pt 2): 067403, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14754363

RESUMO

The ablation pressure at a 0.44-microm laser wavelength has been measured at irradiance up to 2 x 10(14) W/cm(2). The diagnostics consisted in the detection of shock breakout from stepped Al targets. By adopting large focal spots and smoothed laser beams, the lateral energy transport and "drilling effects" have been avoided. The measured scaling shows a fair agreement with analytical models.

11.
Hepatology ; 30(3): 649-54, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10462370

RESUMO

Cirrhosis is often associated with insulin resistance and glucose intolerance. We evaluated if these alterations are restored by liver transplantation (LT). Glucose tolerance (oral glucose tolerance test [OGTT]), peripheral insulin sensitivity (euglycemic insulin clamp technique), glucose oxidation (indirect calorimetry), nonoxidative glucose disposal, and insulin secretion (hyperglycemic clamp technique) were measured in 6 patients (Group 1) before and 6 months after LT, in 12 patients (Group 2) who underwent LT 6 to 30 months previously, and in 6 healthy individuals (controls). In Group 1, glucose tolerance and insulin sensitivity (3.24 +/- 0.37 mg/kg/min) were normalized after LT (8.6 +/- 0.77 mg/kg/min; P <.0001; P = not significant vs. controls). The improved insulin-mediated glucose uptake was the result of a normalization of nonoxidative glucose disposal. Fasting insulin and C-peptide decreased from 24.6 +/- 3.3 microU/mL and 4.37 +/- 0.46 ng/dL, respectively, to 12.7 +/- 1.9 microU/mL and 2.46 +/- 0.5 ng/dL (controls: 10.0 +/- 3 microU/mL and 1.45 +/- 0.34 ng/dL). The glucose-induced increase of insulin concentration, which was higher before LT, showed a significant reduction, although the first phase of beta-cell secretion remained significantly higher compared with that of controls. All these findings were also confirmed in Group 2. The present data indicate that LT normalizes glucose tolerance and insulin sensitivity in cirrhotic patients through an improvement of both hepatic glucose clearance and the peripheral glucose disposal. The latter effect may be the result of the correction of chronic hyperinsulinemia. An increased first-phase beta-cell insulin secretion in response to high glucose levels persists, suggesting that a memory of previous insulin resistance is maintained.


Assuntos
Glicemia/análise , Resistência à Insulina , Cirrose Hepática/cirurgia , Transplante de Fígado , Adulto , Feminino , Teste de Tolerância a Glucose , Humanos , Cirrose Hepática/metabolismo , Masculino , Pessoa de Meia-Idade
12.
Phys Rev Lett ; 92(6): 065503, 2004 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-14995252

RESUMO

We present an experimental point for the carbon equation of state (EOS) at megabar pressures, obtained by laser-driven shock waves. The rear side emissivity of "two-materials two-steps" targets (Al-C) was recorded with space and time resolution and, by applying the impedance mismatch method, allowed a direct determination of relative EOS points. Experiments were performed at the PALS and LULI laboratories using carbon samples with two different values of initial density, in order to explore a wider region of the phase diagram. Previously unreached pressures were obtained. The results are compared with previous experiments and with available theoretical models and seem to show a high compressibility of carbon at megabar pressures.

SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa