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1.
Acta Psychiatr Scand ; 136(3): 323-331, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28669135

RESUMO

OBJECTIVE: To describe the pharmacological management of borderline personality disorder (BPD) in Spain from 2001 through 2016, the factors associated with prescriptions, and changes in pharmacotherapy over this time period. METHODS: Retrospective, cross-sectional, observational study conducted in a sample of 457 patients with BPD consecutively admitted to a specialist BPD Program between January 2001 and November 2016. Data on sociodemographic and clinical variables, as well as pharmacological treatment upon the admission to the programme, were used to describe pharmacological prescriptions, the factors associated with these medications, and changes in prescription over the last 15 years. RESULTS: Most (88.4%) patients were on pharmacological treatment, with 53.8% of persons taking ≥3 medications. No significant changes in these percentages were observed over the study period. The use of tricyclic antidepressants and benzodiazepines decreased, while the use of atypical antipsychotics increased. Axis I comorbidity was the main factor associated with pharmacological treatment and polypharmacy. CONCLUSIONS: This study provides further evidence confirming the worldwide overuse of prescription medications for BPD and shows that there has been a shift in the prescription pattern in the last 15 years. These results suggest that real clinical practice only partially adheres to clinical treatment guidelines.


Assuntos
Antidepressivos Tricíclicos/uso terapêutico , Antipsicóticos/uso terapêutico , Benzodiazepinas/uso terapêutico , Transtorno da Personalidade Borderline/tratamento farmacológico , Prescrições de Medicamentos/estatística & dados numéricos , Adulto , Transtorno da Personalidade Borderline/epidemiologia , Comorbidade , Estudos Transversais , Feminino , Humanos , Masculino , Estudos Retrospectivos , Espanha/epidemiologia , Adulto Jovem
2.
J Comp Physiol B ; 193(1): 25-36, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36342510

RESUMO

Spider dragline fibers exhibit incredible mechanical properties, outperforming many synthetic polymers in toughness assays, and possess desirable properties for medical and other human applications. These qualities make dragline fibers popular subjects for biomimetics research. The enormous diversity of spiders presents both an opportunity for the development of new bioinspired materials and a challenge for the identification of fundamental design principles, as the mechanical properties of dragline fibers show both intraspecific and interspecific variations. In this regard, the stress-strain curves of draglines from different species have been shown to be effectively compared by the α* parameter, a value derived from maximum-supercontracted silk fibers. To identify potential molecular mechanisms impacting α* values, here we analyze spider fibroin (spidroin) sequences of the Western black widow (Latrodectus hesperus) and the black and yellow garden spider (Argiope aurantia). This study serves as a primer for investigating the molecular properties of spidroins that underlie species-specific α* values. Initial findings are that while overall motif composition was similar between species, certain motifs and higher level periodicities of glycine-rich region lengths showed variation, notably greater distances between poly-A motifs in A. aurantia sequences. In addition to increased period lengths, A. aurantia spidroins tended to have an increased prevalence of charged and hydrophobic residues. These increases may impact the number and strength of hydrogen bond networks within fibers, which have been implicated in conformational changes and formation of nanocrystals, contributing to the greater extensibility of A. aurantia draglines compared to those of L. hesperus.


Assuntos
Fibroínas , Aranhas , Humanos , Animais , Fibroínas/química , Seda/química , Seda/fisiologia , Prevalência , Especificidade da Espécie
3.
Biomacromolecules ; 13(7): 2087-98, 2012 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-22668322

RESUMO

The mechanical behavior and microstructure of minor ampullate gland silk (miS) of two orb-web spinning species, Argiope trifasciata and Nephila inaurata, were extensively characterized, enabling detailed comparison with other silks. The similarities and differences exhibited by miS when compared with the intensively studied major ampullate gland silk (MAS) and silkworm (Bombyx mori) silk offer a genuine opportunity for testing some of the hypotheses proposed to correlate microstructure and tensile properties in silk. In this work, we show that miSs of different species show similar properties, even when fibers spun by spiders that diverged over 100 million years are compared. The tensile properties of miS are comparable to those of MAS when tested in air, significantly in terms of work to fracture, but differ considerably when tested in water. In particular, miS does not show a supercontraction effect and an associated ground state. In this regard, the behavior of miS in water is similar to that of B. mori silk, and it is shown that the initial elastic modulus of both fibers can be explained using a common model. Intriguingly, the microstructural parameters measured in miS are comparable to those of MAS and considerably different from those found in B. mori. This fact suggests that some critical microstructural information is still missing in our description of silks, and our results suggest that the hydrophilicity of the lateral groups or the large scale organization of the sequences might be routes worth exploring.


Assuntos
Seda/química , Aranhas , Resistência à Tração , Animais , Módulo de Elasticidade , Feminino , Microscopia de Força Atômica , Seda/ultraestrutura , Análise Espectral Raman , Água/química , Difração de Raios X
4.
Eur Neuropsychopharmacol ; 56: 4-12, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34875491

RESUMO

The COVID-19 pandemic is expected to increase suicidal behavior. However, data available to date are inconsistent. This study examines suicidal thoughts and behaviors and suicide trends in 2020 relative to 2019 as an approximation to the impact of the pandemic on suicidal behavior and death in the general population of Catalonia, Spain. Data on suicide-related thoughts and behaviors (STBs) and suicidal mortality were obtained from the Catalonia Suicide Risk Code (CSRC) register and the regional police, respectively. We compared the monthly crude incidence of STBs and suicide mortality rates of 2020 with those of 2019. Joinpoint regression analysis was used to assess changes in trends over time during the studied period. In 2020, 4,263 consultations for STBs and 555 suicide deaths were registered in Catalonia (approx. 7.5 million inhabitants). Compared to 2019, in 2020 STBs rates decreased an average of 6.3% (incidence rate ratio, IRR=0.94, 95% CI 0,90-0,98) and overall suicide death rates increased 1.2% (IRR=1.01, 95% CI 0.90-1.13). Joinpoint regression results showed a substantial decrease in STBs rates with a monthly percent change (MPC) of -22.1 (95% CI: -41.1, 2.9) from January-April 2020, followed by a similar increase from April-July 2020 (MPC=24.7, 95% CI: -5.9, 65.2). The most restrictive measures implemented in response to the COVID-19 pandemic reduced consultations for STBs, suggesting that the "stay at home" message may have discouraged people from contacting mental health services. STBs and mortality should continue to be monitored in 2021 and beyond to understand better the mid-to-long term impact of COVID-19 on suicide trends.


Assuntos
COVID-19 , Suicídio , Humanos , Pandemias , SARS-CoV-2 , Espanha/epidemiologia , Ideação Suicida , Tentativa de Suicídio
5.
J Exp Med ; 184(1): 215-28, 1996 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-8691136

RESUMO

T cell development in the thymus requires the establishment of stable interactions with cell-selecting elements such as the cortical epithelium followed by a regulated movement of selected progenitors to the medulla. Cell adhesion and migration are mediated by integrins in a number of biological systems though little is known regarding their function in the thymus. We demonstrated previously that immature CD3loCD69lo double positive human thymocytes adhere avidly to FN via the integrin, VLA4. We now demonstrate that the interaction of mature CD3hiCD69hi thymic subsets with FN triggers migration rather than firm adhesion. Migration requires the engagement of VLA4 in cooperation with VLA5 and both receptors regulate the persistence and directionality of movement. While migration capability is linked to maturation state, ligand concentration determines the efficiency of migration. In fact, FN and the alternatively spliced CS1 site are predominant in the thymic medulla, suggesting an instructive role of this ECM protein in vivo. Our studies identify a novel VLA4 and VLA5/FN-mediated pathway likely to be involved in regulating cell traffic between the cortex and medulla of the thymus. Moreover, the data provides evidence that VLA4 exists in at least two functional states at distinct stages of T cell development. While different states of VLA4 activation have been described on cell lines, this represents the first evidence supporting a biological significance for this integrin property.


Assuntos
Adesão Celular , Movimento Celular , Fibronectinas/fisiologia , Integrinas/fisiologia , Receptores de Fibronectina/fisiologia , Receptores de Retorno de Linfócitos/fisiologia , Subpopulações de Linfócitos T/citologia , Sítios de Ligação , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD8-Positivos/citologia , Moléculas de Adesão Celular/fisiologia , Diferenciação Celular , Células Cultivadas , Criança , Pré-Escolar , Humanos , Lactente , Integrina alfa4beta1 , Timo/citologia , Timo/crescimento & desenvolvimento
6.
J Exp Med ; 178(1): 279-84, 1993 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-7686213

RESUMO

Leukocyte extravasation is mediated by multiple interactions of adhesive surface structures with ligands on endothelial cells and matrix components. The functional role of beta 1 (CD29) integrins (or very late antigen [VLA] proteins) in eosinophil migration across polycarbonate filters was examined under several in vitro conditions. Eosinophil migration induced by the chemoattractant C5a or platelet-activating factor was fully inhibited by monoclonal antibody (mAb) 8A2, a recently characterized "activating" CD29 mAb. However, inhibition by mAb 8A2 was observed only under filter conditions that best reflected the in vivo situation, i.e., when the eosinophils migrated over filters preincubated with the extracellular matrix (ECM) protein fibronectin (FN), or when the filters were covered with confluent monolayers of cultured human umbilical vein endothelial cells (HUVEC). When bare untreated filters were used, mAb 8A2 had no effect, whereas the C5a-directed movement was prevented by CD18 mAb. Studies with alpha-subunit (CD49)-specific mAbs indicated that the integrins VLA-4 and -5 mediated migration across FN-preincubated filters, and VLA-2, -4, -5, and -6 were involved in eosinophil migration through filters covered with HUVEC. In contrast with the activating CD29 mAb 8A2, a combination of blocking CD49 mAbs or the nonactivating but blocking CD29 mAb AIIB2 failed to inhibit completely eosinophil migration over FN-preincubated or HUVEC-covered filters. mAb 8A2 stimulated binding to FN but not to HUVEC. Moreover, eosinophil migration over FN-preincubated or HUVEC-covered filters was significantly inhibited by anti-connecting segment 1 (CS-1) mAbs, as well as the soluble CS-1 peptide (unlike migration across bare untreated filters). Thus, inhibition of eosinophil migration by mAb 8A2 depended upon the presence of ECM proteins and not upon the presence of HUVEC per se. In conclusion, "freezing" adhesion receptors of the beta 1 integrin family into their high-avidity binding state by the activating CD29 mAb 8A2 results in a complete inhibition of eosinophil migration under physiological conditions. Hence, activation of beta 1 integrin-mediated cell adhesion may represent a new approach to prevent influx of inflammatory cells.


Assuntos
Moléculas de Adesão Celular/fisiologia , Eosinófilos/fisiologia , Anticorpos Monoclonais/imunologia , Antígenos CD/fisiologia , Antígenos CD18 , Células Cultivadas , Quimiotaxia de Leucócito , Endotélio Vascular/fisiologia , Congelamento , Humanos , Integrina beta1 , Integrinas/fisiologia , Receptores de Antígeno muito Tardio/fisiologia
7.
J Cell Biol ; 112(1): 169-81, 1991 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1986004

RESUMO

The capability of the integrin VLA-3 to function as a receptor for collagen (Coll), laminin (Lm), and fibronectin (Fn) was addressed using both whole cell adhesion assays and ligand affinity columns. Analysis of VLA-3-mediated cell adhesion was facilitated by the use of a small cell lung carcinoma line (NCI-H69), which expresses VLA-3 but few other integrins. While VLA-3 interaction with Fn was often low or undetectable in cells having both VLA-3 and VLA-5, NCI-H69 cells readily attached to Fn in a VLA-3-dependent manner. Both Arg-Gly-Asp (RGD) peptide inhibition studies, and Fn fragment affinity columns suggested that VLA-3, like VLA-5, may bind to the RGD site in human Fn. However, unlike Fn, both Coll and Lm supported VLA-3-mediated adhesion that was not inhibited by RGD peptide, and was totally unaffected by the presence of VLA-5. In addition, VLA-3-mediated binding to Fn was low in the presence of Ca++, but was increased 6.6-fold with Mg++, and 30-fold in the presence of Mn++. In contrast, binding to Coll was increased only 1.2-fold with Mg++, and 1.7-fold in Mn++, as compared to the level seen with Ca++. Together, these experiments indicate that VLA-3 can bind Coll, Lm, and Fn, and also show that (a) VLA-3 can recognize both RGD-dependent and RGD-independent ligands, and (b) different VLA-3 ligands have distinctly dissimilar divalent cation sensitivities.


Assuntos
Adesão Celular/fisiologia , Colágeno/metabolismo , Fibronectinas/metabolismo , Integrinas/metabolismo , Laminina/metabolismo , Sequência de Aminoácidos , Ligação Competitiva , Cátions Bivalentes/farmacologia , Adesão Celular/efeitos dos fármacos , Cromatografia de Afinidade , Matriz Extracelular/metabolismo , Humanos , Integrinas/efeitos dos fármacos , Integrinas/fisiologia , Dados de Sequência Molecular , Oligopeptídeos/farmacologia , Células Tumorais Cultivadas
9.
J Clin Invest ; 95(6): 2601-10, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7539456

RESUMO

Graft arteriopathy, a leading cause of cardiac allograft failure, is associated with increased intimal smooth muscle cells, inflammatory cells, and accumulation of extracellular matrix. We hypothesized that cellular fibronectin plays a pivotal role in the progression of the allograft arteriopathy by directing the transendothelial trafficking of inflammatory cells through interaction of the connecting segment-1 (CS1) motif with the very late antigen-4 (VLA-4) integrin, and tested this in vivo using a blocking peptide. Cholesterol-fed rabbits underwent heterotopic cardiac transplantation without immunosuppression. The treatment group (n = 7) received a synthetic CS1 peptide (1 mg/kg per d, subcutaneously), and the controls (n = 7) received an inactive peptide (1 mg/kg per d, subcutaneously). At 7-8 d after transplantation, hearts were harvested and sectioned for morphometric analysis and immunohistochemical studies. We observed a > 50% decrease in the incidence (P < 0.001) and severity (P < 0.001) of donor coronary artery intimal thickening in the CS1-treated compared with the control group. These findings correlated with reduced infiltration of T cells (P < 0.05), a trend toward decreased expression of adhesion molecules (P < 0.06), and less accumulation of fibronectin (P < 0.03). Our data suggest that the VLA-4-fibronectin interaction is critical to the progression of the allograft arteriopathy by perpetuating the immune-inflammatory response in the vessel wall.


Assuntos
Doença das Coronárias/prevenção & controle , Fibronectinas/metabolismo , Transplante de Coração/métodos , Linfócitos/citologia , Peptídeos/farmacologia , Receptores de Antígeno muito Tardio/metabolismo , Sequência de Aminoácidos , Animais , Ligação Competitiva , Adesão Celular , Moléculas de Adesão Celular/metabolismo , Dieta Aterogênica , Feminino , Fibronectinas/química , Antígenos de Histocompatibilidade Classe II/metabolismo , Molécula 1 de Adesão Intercelular/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular , Dados de Sequência Molecular , Fragmentos de Peptídeos/metabolismo , Coelhos , Molécula 1 de Adesão de Célula Vascular
10.
J Clin Invest ; 93(1): 405-16, 1994 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8282813

RESUMO

Expression of fibronectin (FN) isoforms containing CS1, a 25-amino acid sequence present within the alternatively spliced IIICS region of FN, has been analyzed in rheumatoid arthritis (RA) synovium. Unexpectedly, CS1-containing FN variants were exclusively found on endothelium but not extracellular matrix (ECM) of RA synovium. Lumenal expression of CS1 on RA endothelial cells, as observed by electron microscopy, correlated with inflammation in RA, since normal synovium expressed little CS1 without appreciable decrease in ECM FN. CS1 expression on human endothelial cells was further shown by FN mRNA analyses. In adhesion assays on frozen RA synovial sections, T lymphoblastoid cells expressing functionally activated alpha 4 beta 1 integrin specifically attached to the intravascular surface of RA endothelium. Binding was abrogated by both anti-alpha 4 integrin and CS1 peptides. Our observations suggest direct involvement of CS1-containing FN in recruitment of alpha 4 beta 1-expressing mononuclear leukocytes in synovitis, and provide basis for therapeutic intervention in RA.


Assuntos
Processamento Alternativo , Artrite Reumatoide/metabolismo , Endotélio Vascular/metabolismo , Fibronectinas/biossíntese , Microcirculação/metabolismo , RNA Mensageiro/metabolismo , Membrana Sinovial/irrigação sanguínea , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais , Artrite Reumatoide/genética , Artrite Reumatoide/fisiopatologia , Adesão Celular , Linhagem Celular , Fibronectinas/genética , Variação Genética , Humanos , Técnicas Imunoenzimáticas , Camundongos , Camundongos Endogâmicos BALB C/imunologia , Microscopia Imunoeletrônica , Dados de Sequência Molecular , Peptídeos/síntese química , Peptídeos/imunologia , RNA Mensageiro/análise , RNA Mensageiro/biossíntese , Linfócitos T/imunologia , Linfócitos T/metabolismo
11.
J Clin Invest ; 103(5): 613-25, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10074478

RESUMO

We have shown previously that treatment of human aortic endothelial cells (HAECs) with minimally modified low-density lipoprotein (MM-LDL) induces monocyte but not neutrophil binding. This monocyte binding was not mediated by endothelial E-selectin, P-selectin, vascular cell adhesion molecule-I, or intercellular adhesion molecule-I, suggesting an alternative monocyte-specific adhesion molecule. We now show that moncytic alpha4beta1 integrins mediate binding to MM-LDL-treated endothelial cells. We present data suggesting that the expression of the connecting segment-1 (CS-1) domain of fibronectin (FN) is induced on the apical surface of HAEC by MM-LDL and is the endothelial alpha4beta1 ligand in MM-LDL-treated cells. Although the levels of CS-1 mRNA and protein were not increased, we show that MM-LDL treatment causes deposition of FN on the apical surface by activation of beta1integrins, particularly those associated with alpha5 integrins. Activation of beta1 by antibody 8A2 also induced CS-1-mediated monocyte binding. Confocal microscopy demonstrated the activated beta1 and CS-1colocalize in concentrated filamentous patches on the apical surface of HAEC. Both anti-CS-1 and an antibody to activated beta1 showed increased staining on the luminal endothelium of human coronary lesions with active monocyte entry. These results suggest the importance of these integrin ligand interactions in human atherosclerosis.


Assuntos
Endotélio Vascular/citologia , Integrina beta1/metabolismo , Lipoproteínas LDL/farmacologia , Monócitos/citologia , Peptídeos/metabolismo , Adesão Celular/efeitos dos fármacos , Células Cultivadas , Endotélio Vascular/metabolismo , Fibronectinas/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intercelular , Lipoproteínas LDL/metabolismo , Microscopia Confocal , Monócitos/metabolismo
12.
Phys Rev E Stat Nonlin Soft Matter Phys ; 76(4 Pt 1): 041903, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17995022

RESUMO

A great number of biological structures are composed of fibers (elastin, collagen, etc.) dispersed on an aqueous matrix in such a complex way that a detailed mechanical analysis based on microconstituents is, for practical purposes, out of reach. Consequently, the preferred approach to the mechanical behavior of these materials is based on setting up of constitutive equations that homogenize the behavior while capturing their main microstructural features. This work presents a simple macroscopic model for fiber-reinforced materials with deformable matrices, especially suited to many biological structural tissues. The constitutive equation is derived by imposing equivalence between the virtual works of both the fiber-reinforced and the equivalent continuum media, showing that it is independent of the control volume used for such equivalence. The model is particularized to incompressible materials, and an extension to orthotropic biological fibers is shown. Numerical simulations of uniaxial tests on silk fibers demonstrate the model's ability to capture the progressive alignment of the microconstituents under large deformations.


Assuntos
Biofísica/métodos , Algoritmos , Colágeno/química , Cristalização , Elastina/química , Ligação de Hidrogênio , Modelos Estatísticos , Modelos Teóricos , Física/métodos , Seda , Estresse Mecânico
13.
Sci Rep ; 5: 14820, 2015 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-26438975

RESUMO

The extraordinary mechanical performance of spider dragline silk is explained by its highly ordered microstructure and results from the sequences of its constituent proteins. This optimized microstructural organization simultaneously achieves high tensile strength and strain at breaking by taking advantage of weak molecular interactions. However, elucidating how the original design evolved over the 400 million year history of spider silk, and identifying the basic relationships between microstructural details and performance have proven difficult tasks. Here we show that the analysis of maximum supercontracted single spider silk fibers using X ray diffraction shows a complex picture of silk evolution where some key microstructural features are conserved phylogenetically while others show substantial variation even among closely related species. This new understanding helps elucidate which microstructural features need to be copied in order to produce the next generation of biomimetic silk fibers.


Assuntos
Seda/química , Seda/ultraestrutura , Aranhas , Animais , Evolução Biológica , Filogenia , Resistência à Tração , Difração de Raios X
14.
J Histochem Cytochem ; 48(8): 1121-30, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10898805

RESUMO

This study was designed to investigate (a) the presence of protein gene product 9.5 (PGP 9.5), ubiquitin, and neuropeptide Y (NPY) in the neuroendocrine and secretory epithelium of the human normal prostate and its secretions, and (b) the changes in immunoreactivity to these proteins in men with benign prostatic hyperplasia. Western blotting and light microscopic immunohistochemistry techniques were used and the numerical density of immunoreactive neuroendocrine cells, and the volume fractions of immunostained secretory epithelium were evaluated. Western blotting revealed the presence of the three antigens in both tissue homogenates and prostate secretion. Some neuroendocrine cells immunoreacted to PGP 9.5 and NPY in all the prostate regions of control specimens. Ubiquitin immunoreactivity was detected in the nuclei from both basal cells and secretory epithelial cells. The cytoplasm of the secretory cells and the glandular lumen also showed immunostaining for the three proteins. The numerical densities of both PGP 9.5 and NPY neuroendocrine cells were lower in hyperplasia than in controls. No differences in the volume fraction occupied by epithelial immunostaining to both proteins was found between hyperplastic and control prostates. We concluded that (a) PGP 9.5 and NPY, but not ubiquitin, are common antigens in both neuroendocrine and secretory prostate cells, (b) the three immunoreactive proteins contribute to the prostate secretions, and (c) the secretion of ubiquitin is markedly diminished in the hyperplastic epithelium.(J Histochem Cytochem 48:1121-1130, 2000)


Assuntos
Células Epiteliais/metabolismo , Neuropeptídeo Y/metabolismo , Sistemas Neurossecretores/metabolismo , Próstata/metabolismo , Hiperplasia Prostática/metabolismo , Tioléster Hidrolases/metabolismo , Ubiquitinas/metabolismo , Idoso , Idoso de 80 Anos ou mais , Western Blotting , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Sistemas Neurossecretores/citologia , Próstata/citologia , Hiperplasia Prostática/patologia , Ubiquitina Tiolesterase
15.
Int J Oncol ; 10(3): 457-64, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21533397

RESUMO

The role of VLA-4 integrin in liver metastasis of lymphoma cells was investigated. ESbL-lacZ lymphoma cells in vitro exhibited high surface expression of VLA-4, adhered to CS-1 fibronectin and VCAM-1 and cell adhesion was inhibited by anti-VLA-4 MAb PS/2. When injected in vivo, however, PS/2 did not interfere with spontaneous liver metastasis and had no effect on survival. Ex vivo analysis of VLA-4 surface expression was facilitated by a new reisolation method for tumor and host cells derived from metastatic target organs. Freshly ex vivo isolated tumor cells from metastatic livers revealed VLA-4 surface downregulation as early as 3 days after tumor injection, which continued during the course of metastasis. VLA-4 downregulation in liver metastasis was also seen at the mRNA transcriptional level. Primary tumor cells showed similar VLA-4 downregulation suggesting that the in vivo phenotype was induced by the microenvironment at the primary tumor site. In support of this hypothesis, re-isolated tumor cells from metastatic livers recovered the high VLA-4 expression in host-depleted cell cultures. This study suggests that VLA-4 expression on tumor cells can be modulated in situ during tumor growth and metastasis formation.

16.
Curr Opin Investig Drugs ; 2(3): 372-4, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11575707

RESUMO

Tresperimus (LF-08-0299) is an immunosuppressant under development by Laboratoires Fournier for its potential use in organ transplant rejection. Fournier has commenced phase III trials in the US and Europe [304203]. Tresperimus began phase I/II trials in 1995 for graft versus host rejection in combination with cyclosporine and tacrolimus, but later as first-line therapy. It demonstrated efficient immunosuppressive activity in a rat model of cardiac rejection [182951]. The company is seeking licensees for the product


Assuntos
Carbamatos/farmacologia , Drogas em Investigação , Imunossupressores/farmacologia , Animais , Carbamatos/química , Carbamatos/uso terapêutico , Carbamatos/toxicidade , Ensaios Clínicos Fase I como Assunto , Ensaios Clínicos Fase II como Assunto , Avaliação Pré-Clínica de Medicamentos , Quimioterapia Combinada , Previsões , Doença Enxerto-Hospedeiro/prevenção & controle , Humanos , Imunossupressores/uso terapêutico , Estrutura Molecular , Prednisolona/uso terapêutico
17.
Clin Exp Rheumatol ; 11 Suppl 8: S77-80, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8324956

RESUMO

We have developed a murine model of delayed type hypersensitivity (DTH) to the chemical oxazalone. Purification of T lymphocytes from immunized animals allows adoptive transfer of the specific DTH response into naive recipients injected intravenously with primed T cells. Transfer of DTH elicited by injection with immune T cells can be specifically inhibited by antibodies to the VLA-4 integrin receptor. These results suggest a major role for VLA-4 in skin inflammatory reactions in vivo.


Assuntos
Dermatite/patologia , Leucócitos/fisiologia , Receptores de Antígeno muito Tardio/fisiologia , Animais , Movimento Celular/fisiologia , Dermatite/imunologia , Dermatite/fisiopatologia , Hipersensibilidade Tardia/imunologia , Imunoterapia Adotiva , Leucócitos/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Oxazolona/imunologia
18.
IDrugs ; 1(2): 221-7, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18465535

RESUMO

AN-100226 (Antegren), a humanized monoclonal antibody (MAb) directed against the alpha4beta1 integrin (VLA-4) expressed on leukocytes, is under development by Athena Neurosciences as a potential treatment of exacerbations in multiple sclerosis (MS). VLA-4 specifically binds to VCAM-1, a ligand present on brain endothelial cells which is a potential mediator of autoimmune disorders, leading to MS [222518]. Phase II trials in 70 patients with MS in the UK were assessed over a 12-week period. Antegren significantly reduced new brain lesions [275424]. In two separate pilot studies involving a total of 40 patients suffering from Crohn's disease or ulcerative colitis, treatment with Antegrin was well-tolerated and efficacious. Interim analysis of phase II data has indicated promising results [179966,276967]. Antegren is claimed in the associated patent, WO-09519790. VLA-4 itself and monoclonal antibodies for the integrin were first described in a patent (EP-00330506) by the Dana-Farber Cancer Institute. In April 1998, Protein Design Labs (PDL) granted a worldwide, non-exclusive license for Antegren under its antibody humanization patents, to a subsidiary of Elan [286198].

19.
Carbohydr Res ; 203(1): 109-18, 1990 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-2146013

RESUMO

An N-acetyl-beta-D-glucosaminyltransferase activity involved in the initiation of poly-N-acetyllactosamine chain biosynthesis can be solubilized from Ehrlich ascites tumor cell microsomal membranes. The ability of this enzyme to act on linear and branched acceptor substrates has been studied. The results indicate that complex-type tri- and tetra-antennary oligosaccharides exhibiting the branching pattern beta-D-Galp-(1----4)-beta-D-GlcpNAc-(1----6)-[beta-D-Galp-(1----4)-beta- D- Glcp-NAc-(1----2)]-D-Man are the preferred substrates for the enzyme, and therefore, may represent the structures upon which the generation of poly-N-acetyllactosamine chains proceeds more efficiently.


Assuntos
Asparagina/química , N-Acetilglucosaminiltransferases , Oligossacarídeos/química , Polissacarídeos/biossíntese , Animais , Configuração de Carboidratos , Sequência de Carboidratos , Carcinoma de Ehrlich/enzimologia , Extratos Celulares/farmacologia , Cromatografia em Gel , Glucosiltransferases/metabolismo , Glicosídeo Hidrolases , Dados de Sequência Molecular , Estrutura Molecular , Especificidade por Substrato
20.
Phys Rev E Stat Nonlin Soft Matter Phys ; 90(5-1): 052715, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25493824

RESUMO

Mechanical deformability of cells is a key property that influences their ability to migrate and their contribution to tissue development and regeneration. We analyze here the possibility of characterizing the overall deformability of cells by their apparent viscosity, using a simplified method to estimate that parameter. The proposed method simplifies the quantitative analysis of micropipette-aspiration experiments. We have studied by this procedure the overall apparent viscosity of cardiac stem cells, which are considered a promising tool to regenerate damaged cardiac tissue. Comparison with the apparent viscosity of low-viscosity cells such as immune-system cells suggests that treatments to reduce the viscosity of these cells could enhance their ability to repair damaged cardiac tissue.

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