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1.
Aliment Pharmacol Ther ; 59(12): 1604-1615, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38690746

RESUMO

BACKGROUND: Suboptimal response to ursodeoxycholic acid occurs in 40% of primary biliary cholangitis (PBC) patients, affecting survival. Achieving a deep response (normalisation of alkaline phosphatase [ALP] and bilirubin ≤0.6 upper limit of normal) improves survival. Yet, the long-term effectiveness of second-line treatments remains uncertain. AIMS: To evaluate the long-term effectiveness of obeticholic acid (OCA) ± fibrates. Focusing on biochemical response (ALP ≤1.67 times the upper limit of normal, with a decrease of at least 15% from baseline and normal bilirubin levels), normalisation of ALP, deep response and biochemical remission (deep response plus aminotransferase normalisation). METHODS: We conducted a longitudinal, observational, multicentre study involving ursodeoxyccholic acid non-responsive PBC patients (Paris-II criteria) from Spain and Portugal who received OCA ± fibrates. RESULTS: Of 255 patients, median follow-up was 35.1 months (IQR: 20.2-53). The biochemical response in the whole cohort was 47.2%, 61.4% and 68.6% at 12, 24 and 36 months. GLOBE-PBC and 5-year UK-PBC scores improved (p < 0.001). Triple therapy (ursodeoxycholic acid plus OCA plus fibrates) had significantly higher response rates than dual therapy (p = 0.001), including ALP normalisation, deep response and biochemical remission (p < 0.001). In multivariate analysis, triple therapy remained independently associated with biochemical response (p = 0.024), alkaline phosphatase normalisation, deep response and biochemical remission (p < 0.001). Adverse effects occurred in 41.2% of cases, leading to 18.8% discontinuing OCA. Out of 55 patients with cirrhosis, 12 developed decompensation. All with baseline portal hypertension. CONCLUSION: Triple therapy was superior in achieving therapeutic goals in UDCA-nonresponsive PBC. Decompensation was linked to pre-existing portal hypertension.


Assuntos
Fosfatase Alcalina , Ácido Quenodesoxicólico , Colagogos e Coleréticos , Quimioterapia Combinada , Cirrose Hepática Biliar , Ácido Ursodesoxicólico , Humanos , Ácido Quenodesoxicólico/análogos & derivados , Ácido Quenodesoxicólico/uso terapêutico , Masculino , Feminino , Pessoa de Meia-Idade , Ácido Ursodesoxicólico/uso terapêutico , Estudos Longitudinais , Cirrose Hepática Biliar/tratamento farmacológico , Idoso , Resultado do Tratamento , Fosfatase Alcalina/sangue , Colagogos e Coleréticos/uso terapêutico , Ácidos Fíbricos/uso terapêutico , Espanha , Bilirrubina/sangue , Adulto
3.
Toxicol Lett ; 394: 138-145, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38458340

RESUMO

Benzocaine is a widely employed local anaesthetic; however, there is a notable dearth of preclinical and clinical evidence regarding its safety in ophthalmological products. To address this, a comprehensive strategy incorporating in silico and in vitro methodologies was proposed for assessing benzocaine's ocular toxicity without animal testing. To collect the in silico evidence, the QSAR Toolbox (v4.5) was used. A single exposure to two benzocaine concentrations (2% and 20%) was evaluated by in vitro methods. Hen's Egg Chorioallantoic Membrane Test (HET-CAM) was performed to evaluate the effects on the conjunctiva. To study corneal integrity, Short Time Exposure test (STE) and Bovine Corneal Opacity and Permeability (BCOP) assay, followed by histopathological analysis, were carried out. Results from both in silico and in vitro methodologies categorize benzocaine as non-irritating. The histopathological analysis further affirms the safety of using benzocaine in eye drops, as no alterations were observed in evaluated corneal strata. This research proposes a useful combined strategy to provide evidence on the safety of local anaesthetics and particularly show that 2% and 20% benzocaine solutions do not induce eye irritation or corneal damage, supporting the potential use of benzocaine in the development of ophthalmic anesthetic products.


Assuntos
Lesões da Córnea , Opacidade da Córnea , Animais , Bovinos , Feminino , Benzocaína/toxicidade , Galinhas , Córnea , Irritantes/toxicidade , Alternativas aos Testes com Animais
4.
Emerg Microbes Infect ; 9(1): 2728-2731, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33258732

RESUMO

A 40-year-old female was found to have strongly neutralizing SARS-CoV-2 breastmilk IgA and IgG antibodies reactive against multiple SARS-CoV-2 antigens at 2.5 months after documented infection with SARS-CoV-2. At 6.5 months following the infection, she remained positive for breastmilk and serum SARS-CoV-2 neutralizing antibodies. Holder breast milk pasteurization did not diminish SARS-CoV-2 antibody titres but it reduced its neutralizing capacity, while serum heat inactivation had no negative effect on SARS-CoV-2 serum antibody levels and neutralizing capacity. Current data on SARS-CoV-2 and breastmilk are reviewed.


Assuntos
Anticorpos Antivirais/análise , Antígenos Virais/imunologia , Proteínas do Nucleocapsídeo de Coronavírus/imunologia , Leite Humano/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Adulto , Feminino , Humanos , Ligação Proteica , Domínios Proteicos
9.
In Silico Biol ; 12(3-4): 83-93, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-26756921

RESUMO

Articular cartilage is characterized by low cell density of only one cell type, chondrocytes, and has limited self-healing properties. When articular cartilage is affected by traumatic injuries, a therapeutic strategy such as autologous chondrocyte implantation is usually proposed for its treatment. This approach requires in vitro chondrocyte expansion to yield high cell number for cell transplantation. To improve the efficiency of this procedure, it is necessary to assess cell dynamics such as migration, proliferation and cell death during culture. Computational models such as cellular automata can be used to simulate cell dynamics in order to enhance the result of cell culture procedures. This methodology has been implemented for several cell types; however, an experimental validation is required for each one. For this reason, in this research a cellular automata model, based on random-walk theory, was devised in order to predict articular chondrocyte behavior in monolayer culture during cell expansion. Results demonstrated that the cellular automata model corresponded to cell dynamics and computed-accurate quantitative results. Moreover, it was possible to observe that cell dynamics depend on weighted probabilities derived from experimental data and cell behavior varies according to the cell culture period. Thus, depending on whether cells were just seeded or proliferated exponentially, culture time probabilities differed in percentages in the CA model. Furthermore, in the experimental assessment a decreased chondrocyte proliferation was observed along with increased passage number. This approach is expected to having other uses as in enhancing articular cartilage therapies based on tissue engineering and regenerative medicine.


Assuntos
Cartilagem Articular , Morte Celular , Proliferação de Células , Condrócitos , Modelos Biológicos , Técnicas de Cultura de Células , Humanos , Engenharia Tecidual
10.
Neuroscience ; 310: 152-62, 2015 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-26391922

RESUMO

The clinical use of benzodiazepines is limited by the development of tolerance to their pharmacological effects. Tolerance to each of the pharmacological actions of benzodiazepines develops at different rates. The aim of this work was to investigate the mechanism of tolerance by performing behavioral tests in combination with biochemical studies. To this end, we administered prolonged treatments of diazepam to rats for 7 or 14 days. Tolerance to the sedative effects of diazepam was detected by means of the open field test after the 7- and 14-day treatments, whereas tolerance to the anxiolytic actions of benzodiazepine manifested following only the 14-day treatment in the elevated plus maze. The cerebral cortical concentrations of diazepam did not decline after the diazepam treatments, indicating that tolerance was not due to alterations in pharmacokinetic factors. The uncoupling of GABA/benzodiazepine site interactions and an increase in the degree of phosphorylation of the GABAA receptor γ2 subunit at serine 327 in the cerebral cortex were produced by day 7 of diazepam treatment and persisted after 14 days of exposure to benzodiazepine. Thus, these alterations could be part of the mechanism of tolerance to the sedative effects of diazepam. An increase in the percentage of α1-containing GABAA receptors in the cerebral cortex was observed following the 14-day treatment with diazepam but not the 7-day treatment, suggesting that tolerance to the anxiolytic effects is associated with a change in receptor subunit composition. The understanding of the molecular bases of tolerance could be important for the development of new drugs that maintain their efficacies over long-term treatments.


Assuntos
Ansiolíticos/farmacologia , Córtex Cerebral/efeitos dos fármacos , Diazepam/farmacologia , Tolerância a Medicamentos/fisiologia , Regulação da Expressão Gênica/efeitos dos fármacos , Receptores de GABA-A/metabolismo , Animais , Ansiolíticos/metabolismo , Benzodiazepinas/farmacologia , Sítios de Ligação/efeitos dos fármacos , Córtex Cerebral/metabolismo , Diazepam/metabolismo , Esquema de Medicação , Imunoprecipitação , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Ligação Proteica/efeitos dos fármacos , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores de GABA-A/genética , Fatores de Tempo , Ácido gama-Aminobutírico/farmacologia
11.
Comput Methods Programs Biomed ; 118(1): 59-68, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25453383

RESUMO

Mechanical stimuli play a significant role in the process of long bone development as evidenced by clinical observations and in vivo studies. Up to now approaches to understand stimuli characteristics have been limited to the first stages of epiphyseal development. Furthermore, growth plate mechanical behavior has not been widely studied. In order to better understand mechanical influences on bone growth, we used Carter and Wong biomechanical approximation to analyze growth plate mechanical behavior, and explore stress patterns for different morphological stages of the growth plate. To the best of our knowledge this work is the first attempt to study stress distribution on growth plate during different possible stages of bone development, from gestation to adolescence. Stress distribution analysis on the epiphysis and growth plate was performed using axisymmetric (3D) finite element analysis in a simplified generic epiphyseal geometry using a linear elastic model as the first approximation. We took into account different growth plate locations, morphologies and widths, as well as different epiphyseal developmental stages. We found stress distribution during bone development established osteogenic index patterns that seem to influence locally epiphyseal structures growth and coincide with growth plate histological arrangement.


Assuntos
Desenvolvimento Ósseo/fisiologia , Simulação por Computador , Lâmina de Crescimento/crescimento & desenvolvimento , Lâmina de Crescimento/fisiologia , Adolescente , Criança , Pré-Escolar , Epífises/embriologia , Epífises/crescimento & desenvolvimento , Epífises/fisiologia , Feminino , Análise de Elementos Finitos , Lâmina de Crescimento/embriologia , Humanos , Lactente , Recém-Nascido , Modelos Lineares , Masculino , Modelos Biológicos , Osteogênese/fisiologia , Gravidez , Estresse Mecânico
13.
Neuroscience ; 257: 119-29, 2014 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-24215979

RESUMO

Persistent activation of GABAA receptors triggers compensatory changes in receptor function that are relevant to physiological, pathological and pharmacological conditions. Chronic treatment of cultured neurons with GABA for 48h has been shown to produce a down-regulation of receptor number and an uncoupling of GABA/benzodiazepine site interactions with a half-time of 24-25h. Down-regulation is the result of a transcriptional repression of GABAA receptor subunit genes and depends on activation of L-type voltage-gated calcium channels. The mechanism of this uncoupling is currently unknown. We have previously demonstrated that a single brief exposure of rat primary neocortical cultures to GABA for 5-10min (t½=3min) initiates a process that results in uncoupling hours later (t½=12h) without a change in receptor number. Uncoupling is contingent upon GABAA receptor activation and independent of voltage-gated calcium influx. This process is accompanied by a selective decrease in subunit mRNA levels. Here, we report that the brief GABA exposure induces a decrease in the percentage of α3-containing receptors, a receptor subtype that exhibits a high degree of coupling between GABA and benzodiazepine binding sites. Initiation of GABA-induced uncoupling is prevented by co-incubation of GABA with high concentrations of sucrose suggesting that it is dependent on a receptor internalization step. Moreover, results from immunocytochemical and biochemical experiments indicate that GABA exposure causes an increase in GABAA receptor endocytosis. Together, these data suggest that the uncoupling mechanism involves an initial increase in receptor internalization followed by activation of a signaling cascade that leads to selective changes in receptor subunit levels. These changes might result in the assembly of receptors with altered subunit compositions that display a lower degree of coupling between GABA and benzodiazepine sites. Uncoupling might represent a homeostatic mechanism that negatively regulates GABAergic transmission under physiological conditions in which synaptic GABAA receptors are transiently activated for several minutes.


Assuntos
Benzodiazepinas/farmacologia , Neurônios/efeitos dos fármacos , Receptores de GABA-A/química , Receptores de GABA-A/metabolismo , Ácido gama-Aminobutírico/farmacologia , Animais , Benzodiazepinas/metabolismo , Sítios de Ligação/efeitos dos fármacos , Células Cultivadas , Córtex Cerebral/citologia , Embrião de Mamíferos , Flunitrazepam/farmacocinética , Antagonistas GABAérgicos/farmacologia , Moduladores GABAérgicos/farmacocinética , Regulação da Expressão Gênica/efeitos dos fármacos , Picrotoxina/farmacologia , Ligação Proteica/efeitos dos fármacos , Transporte Proteico/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Receptores de GABA-A/genética , Fatores de Tempo , Trítio/farmacocinética
15.
Leukemia ; 27(11): 2149-56, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23579575

RESUMO

Adult acute myeloid leukemia (AML) is a highly heterogeneous stem cell malignancy characterized by the clonal expansion of immature myeloid precursors. AML may emerge de novo, following other hematopoietic malignancies or after cytotoxic therapy for other disorders. Here, we investigated the clonal vs reactive nature of residual maturing bone marrow cells in 59 newly diagnosed adult AML and mixed phenotype acute leukemia (MPAL) patients as assessed by interphase fluorescence in situ hybridization analysis of AML and myelodysplastic syndrome-associated cytogenetic alterations and/or the pattern of chromosome X inactivation, in females. In addition, we investigated the potential association between the degree of molecular/genetic involvement of hematopoiesis and coexistence of altered immunophenotypes by flow cytometry. Our results indicate that residual maturing neutrophils, monocytes and nucleated red cell precursors from the great majority of newly diagnosed AML and MPAL cases show a clonal pattern of involvement of residual maturing hematopoietic cells, in association with a greater number of altered immunophenotypes. These findings are consistent with the replacement of normal/reactive hematopoiesis by clonal myelopoiesis and/or erythropoiesis in most newly diagnosed AML and MPAL cases, supporting the notion that in most adults presenting with de novo AML, accumulation of blast cells could occur over a pre-existing clonal hematopoiesis.


Assuntos
Medula Óssea/patologia , Hematopoese , Leucemia Aguda Bifenotípica/patologia , Leucemia Mieloide Aguda/patologia , Adulto , Idoso , Medula Óssea/imunologia , Feminino , Seguimentos , Humanos , Imunofenotipagem , Hibridização in Situ Fluorescente , Cariotipagem , Leucemia Aguda Bifenotípica/genética , Leucemia Aguda Bifenotípica/imunologia , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/imunologia , Masculino , Pessoa de Meia-Idade , Mutação/genética , Reação em Cadeia da Polimerase , Prognóstico , Proteínas Proto-Oncogênicas c-kit/genética
16.
Acta Biomater ; 8(12): 4295-303, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22842032

RESUMO

Nanoporous silica microparticles (NSiO(2)-MP) are considered to be potential drug delivery systems and scaffolding platforms in tissue engineering. However, few biocompatibility studies regarding NSiO(2)-MP interaction with the immune system have been reported. Toll-like receptors (TLR) are involved in host defence as well as autoimmune and inflammatory diseases. The results show that NSiO(2)-MP up to 100µgml(-1) do not affect macrophage cell viability after 24h cell culture. Moreover, NSiO(2)-MP do not compromise the cell viability of TLR-activated Raw 264.7 cells, for either cell surface TLR (TLR1/TLR2/TLR4/TLR6) or endocytic compartment TLR (TLR3/TLR7/TLR9). Furthermore, Raw 264.7 cells do not respond to NSiO(2)-MP exposure in terms of IL-6 or IL-10 secretion. NSiO(2)-MP co-treatment in the presence of TLR ligands does not impair or enhance the secretion of the pro-inflammatory cytokine IL-6 or the regulatory cytokine IL-10. Thus, NSiO(2)-MP do not affect macrophage polarization towards a pro-inflammatory or immunosuppressive status, representing added value in terms of biocompatibility compared with other SiO(2)-based micro- and nanoparticles.


Assuntos
Sistemas de Liberação de Medicamentos , Macrófagos/metabolismo , Nanopartículas , Dióxido de Silício/farmacologia , Receptores Toll-Like/agonistas , Animais , Linhagem Celular , Interleucina-10/imunologia , Interleucina-10/metabolismo , Interleucina-6/imunologia , Interleucina-6/metabolismo , Ligantes , Macrófagos/citologia , Macrófagos/imunologia , Camundongos , Tamanho da Partícula , Porosidade , Dióxido de Silício/química , Fatores de Tempo , Receptores Toll-Like/imunologia , Receptores Toll-Like/metabolismo
17.
Mod Pathol ; 25(4): 590-601, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22222638

RESUMO

Most genetic studies in colorectal carcinomas have focused on those abnormalities that are acquired by primary tumors, particularly in the transition from adenoma to carcinoma, whereas few studies have compared the genetic abnormalities of primary versus paired metastatic samples. In this study, we used high-density 500K single-nucleotide polymorphism arrays to map the overall genetic changes present in liver metastases (n=20) from untreated colorectal carcinoma patients studied at diagnosis versus their paired primary tumors (n=20). MLH1, MSH2 and MSH6 gene expression was measured in parallel by immunohistochemistry. Overall, metastatic tumors systematically contained those genetic abnormalities observed in the primary tumor sample from the same subject. However, liver metastases from many cases (up to 8 out of 20) showed acquisition of genetic aberrations that were not found in their paired primary tumors. These new metastatic aberrations mainly consisted of (1) an increased frequency of genetic lesions of chromosomes that have been associated with metastatic colorectal carcinoma (1p, 7p, 8q, 13q, 17p, 18q, 20q) and, more interestingly, (2) acquisition of new chromosomal abnormalities (eg, losses of chromosomes 4 and 10q and gains of chromosomes 5p and 6p). These genetic changes acquired by metastatic tumors may be associated with either the metastatic process and/or adaption of metastatic cells to the liver microenvironment. Further studies in larger series of patients are necessary to dissect the specific role of each of the altered genes and chromosomal regions in the metastatic spread of colorectal tumors.


Assuntos
Adenocarcinoma/genética , Adenocarcinoma/secundário , Biomarcadores Tumorais/genética , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Perfilação da Expressão Gênica/métodos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/secundário , Análise de Sequência com Séries de Oligonucleotídeos , Polimorfismo de Nucleotídeo Único , Adenocarcinoma/química , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/análise , Distribuição de Qui-Quadrado , Aberrações Cromossômicas , Neoplasias Colorretais/química , Variações do Número de Cópias de DNA , Feminino , Predisposição Genética para Doença , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Neoplasias Hepáticas/química , Masculino , Repetições de Microssatélites , Pessoa de Meia-Idade , Invasividade Neoplásica , Fenótipo , Prognóstico , Espanha
19.
J Investig Allergol Clin Immunol ; 19(4): 317-20, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19639729

RESUMO

Antihistamines are widely used drugs. Hypersensitivity reactions with these drugs are rare and a challenge for the physician. We describe 5 outpatients who experienced urticaria after taking antihistamines. All 5 were treated at our outpatient clinic over a period of 15 years. The allergy workup included a clinical history, skin prick testing, patch testing with antihistamines, and single-blind placebo-controlled oral challenge tests. Biopsy samples were taken and serum tryptase levels were determined in 1 patient. The results of the skin prick tests and patch tests were negative in all patients but 1, in whom the prick test result was positive to some antihistamines. We confirmed all diagnoses using a single-blind challenge test. The biopsy obtained from 1 patient strongly supported urticaria. We present 5 cases of antihistamine-induced urticaria where the immunologic mechanism remains unclear. Hypersensitivity reactions should be taken into account in patients receiving antihistamines, especially in those who experience urticaria.


Assuntos
Hipersensibilidade a Drogas/imunologia , Antagonistas dos Receptores Histamínicos/efeitos adversos , Urticária/induzido quimicamente , Adulto , Biópsia , Testes de Provocação Brônquica , Hipersensibilidade a Drogas/diagnóstico , Hipersensibilidade a Drogas/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pele/patologia , Testes Cutâneos
20.
Rev Esp Enferm Dig ; 100(8): 481-9, 2008 Aug.
Artigo em Espanhol | MEDLINE | ID: mdl-18942901

RESUMO

OBJECTIVE: To assess the effect of pentoxiphylline (a potent inhibitor of tumor necrosis factor alpha) on survival, on systemic and portal hemodynamics, and on cardiac function in patients with alcoholic cirrhosis. DESIGN: A randomized double-blind placebo-controlled trial. SETTING: A single center using parallel groups of patients to compare pentoxiphylline with placebo. PATIENTS: We recruited 24 patients with alcoholic cirrhosis (8 Child-Pugh B and 16 Child-Pugh C). INTERVENTIONS: Patients were randomly assigned to receive pentoxiphylline (400 mg tid; n = 12) or placebo (n = 12) over a 4-week period. OUTCOME MEASURES: The primary outcome was to extend short-term and long-term survival. Secondary outcomes included hemodynamic benefits (improvement in cardiac function and/or systemic vascular resistance index, or decrease in portal pressure). RESULTS: Portal pressure and cardiac function remained unchanged and there were no significant differences in short-term or long-term survival between treatment and placebo groups. The group on pentoxiphylline increased systemic vascular resistance and decreased cardiac indices (from 1,721 +/- 567 to 2,082 +/- 622 dyn.sec(-1) cm(-5) m(-2) and from 4.17 +/- 1.4 to 3.4 +/- 0.9 l.m(-2), p = 0.05). CONCLUSIONS: Although pentoxiphylline seems to provide some short-term hemodynamic benefits in patients with advanced alcoholic cirrhosis, this drug has no effect on survival or portal pressure in these patients.


Assuntos
Cirrose Hepática Alcoólica/tratamento farmacológico , Cirrose Hepática Alcoólica/fisiopatologia , Pentoxifilina/uso terapêutico , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Método Duplo-Cego , Feminino , Coração/efeitos dos fármacos , Coração/fisiopatologia , Hemodinâmica/efeitos dos fármacos , Humanos , Cirrose Hepática Alcoólica/mortalidade , Masculino , Pessoa de Meia-Idade , Sistema Porta/efeitos dos fármacos , Sistema Porta/fisiopatologia , Índice de Gravidade de Doença , Taxa de Sobrevida
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