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1.
J Immunol ; 212(12): 1981-1991, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38647382

RESUMO

In transplantation, anti-HLA Abs, especially targeting the DQ locus, are well-known to lead to rejection. These Abs identified by Luminex single Ag assays recognize polymorphic amino acids on HLA, named eplets. The HLA Eplet Registry included 83 DQ eplets, mainly deduced from amino acid sequence alignments, among which 66 have not been experimentally verified. Because eplet mismatch load may improve organ allocation and transplant outcomes, it is imperative to confirm the genuine reactivity of eplets to validate this approach. Our study aimed to confirm 29 nonverified eplets, using adsorption of eplet-positive patients' sera on human spleen mononuclear cells and on transfected murine cell clones expressing a unique DQα- and DQß-chain combination. In addition, we compared the positive beads patterns obtained in the two commercially available Luminex single Ag assays. Among the 29 nonverified DQ eplets studied, 24 were confirmed by this strategy, including the 7 DQα eplets 40E, 40ERV, 75I, 76 V, 129H, 129QS, and 130A and the 17 DQß eplets 3P, 23L, 45G, 56L, 57 V, 66DR, 66ER, 67VG, 70GT, 74EL, 86A, 87F, 125G, 130R, 135D, 167R, and 185I. However, adsorption results did not allow us to conclude for the five eplets 66IT, 75S, 160D, 175E, and 185T.


Assuntos
Antígenos HLA-DQ , Humanos , Animais , Camundongos , Antígenos HLA-DQ/imunologia , Teste de Histocompatibilidade/métodos , Rejeição de Enxerto/imunologia , Leucócitos Mononucleares/imunologia , Sequência de Aminoácidos
2.
Nat Methods ; 19(5): 576-585, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35501384

RESUMO

High-resolution structural studies are essential for understanding the folding and function of diverse RNAs. Herein, we present a nanoarchitectural engineering strategy for efficient structural determination of RNA-only structures using single-particle cryogenic electron microscopy (cryo-EM). This strategy-ROCK (RNA oligomerization-enabled cryo-EM via installing kissing loops)-involves installing kissing-loop sequences onto the functionally nonessential stems of RNAs for homomeric self-assembly into closed rings with multiplied molecular weights and mitigated structural flexibility. ROCK enables cryo-EM reconstruction of the Tetrahymena group I intron at 2.98-Å resolution overall (2.85 Å for the core), allowing de novo model building of the complete RNA, including the previously unknown peripheral domains. ROCK is further applied to two smaller RNAs-the Azoarcus group I intron and the FMN riboswitch, revealing the conformational change of the former and the bound ligand in the latter. ROCK holds promise to greatly facilitate the use of cryo-EM in RNA structural studies.


Assuntos
RNA , Riboswitch , Microscopia Crioeletrônica , Ligantes , RNA/genética , Imagem Individual de Molécula
3.
Cancer Cell Int ; 24(1): 228, 2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38951897

RESUMO

BACKGROUND: In the treatment of oral cavity cancer, margin status is one of the most critical prognostic factors. Positive margins are associated with higher local recurrence and lower survival rates. Therefore, the universal goal of oral surgical oncology is to achieve microscopically clear margins. Near-infrared fluorescence guided surgery (FGS) could improve surgical resection using fluorescent probes. αVß6 integrin has shown great potential for cancer targeting due to its overexpression in oral cancers. Red fluorescent contrast agent IRDye 680 coupled with anti-αVß6 peptide (IRDye-A20) represents an asset to improve FGS of oral cancer. This study investigates the potential of IRDye-A20 as a selective imaging agent in 3D three-dimensional tongue cancer cells. METHODS: αVß6 integrin expression was evaluated by RT-qPCR and Western Blotting in 2D HSC-3 human tongue cancer cells and MRC-5 human fibroblasts. Targeting ability of IRDye-A20 was studied in both cell lines by flow cytometry technique. 3D tumor spheroid models, homotypic (HSC-3) and stroma-enriched heterotypic (HSC-3/MRC-5) spheroids were produced by liquid overlay procedure and further characterized using (immuno)histological and fluorescence-based techniques. IRDye-A20 selectivity was evaluated in each type of spheroids and each cell population. RESULTS: αVß6 integrin was overexpressed in 2D HSC-3 cancer cells but not in MRC-5 fibroblasts and consistently, only HSC-3 were labelled with IRDye-A20. Round shaped spheroids with an average diameter of 400 µm were produced with a final ratio of 55%/45% between HSC-3 and MRC-5 cells, respectively. Immunofluorescence experiments demonstrated an uniform expression of αVß6 integrin in homotypic spheroid, while its expression was restricted to cancer cells only in heterotypic spheroid. In stroma-enriched 3D model, Cytokeratin 19 and E-cadherin were expressed only by cancer cells while vimentin and fibronectin were expressed by fibroblasts. Using flow cytometry, we demonstrated that IRDye-A20 labeled the whole homotypic spheroid, while in the heterotypic model all cancer cells were highly fluorescent, with a negligible fluorescence in fibroblasts. CONCLUSIONS: The present study demonstrated an efficient selective targeting of A20FMDV2-conjugated IRDye 680 in 3D tongue cancer cells stroma-enriched spheroids. Thus, IRDye-A20 could be a promising candidate for the future development of the fluorescence-guided surgery of oral cancers.

4.
J Neurosci ; 2022 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-35906069

RESUMO

During human seizures organized waves of voltage activity rapidly sweep across the cortex. Two contradictory theories describe the source of these fast traveling waves: either a slowly advancing narrow region of multiunit activity (an ictal wavefront) or a fixed cortical location. Limited observations and different analyses prevent resolution of these incompatible theories. Here we address this disagreement by combining the methods and microelectrode array recordings (N=11 patients, 2 females, N=31 seizures) from previous human studies to analyze the traveling wave source. We find - inconsistent with both existing theories - a transient relationship between the ictal wavefront and traveling waves, and multiple stable directions of traveling waves in many seizures. Using a computational model that combines elements of both existing theories, we show that interactions between an ictal wavefront and fixed source reproduce the traveling wave dynamics observed in vivo We conclude that combining both existing theories can generate the diversity of ictal traveling waves.Significance StatementThe source of voltage discharges that propagate across cortex during human seizures remains unknown. Two candidate theories exist, each proposing a different discharge source. Support for each theory consists of observations from a small number of human subject recordings, analyzed with separately developed methods. How the different, limited data and different analysis methods impact the evidence for each theory is unclear. To resolve these differences, we combine the unique, human microelectrode array recordings collected separately for each theory and analyze these combined data with a unified approach. We show that neither existing theory adequately describes the data. We then propose a new theory that unifies existing proposals and successfully reproduces the voltage discharge dynamics observed in vivo.

5.
Artigo em Inglês | MEDLINE | ID: mdl-37268785

RESUMO

PURPOSE: Although attention deficit hyperactivity disorder (ADHD) has been associated with illicit stimulants use, less is known about their prospective association in university students. We aimed to examine the association between ADHD symptoms at inclusion and illicit stimulants use following 1 year among university students. METHODS: The i-Share cohort recruited French students from February 2013 to July 2020. The study included 4270 participants. The Adult ADHD Self-Report Scale (ASRS) was used to evaluate ADHD symptoms at inclusion. Illicit stimulants use was assessed at inclusion and 1 year after inclusion. Multivariable logistic regressions were conducted to assess the association between ADHD symptoms at inclusion and illicit stimulants use following 1 year. RESULTS: High levels of ADHD symptoms at inclusion were associated with a greater probability of illicit stimulants use following 1 year (adjusted OR: 2.42 (1.51-3.8)). The adjusted odds ratio was 2.7 (1.08-7.84) among participants who had used illicit stimulant at least once (continuation) and 2.25 (1.04-4.37) among participants who had never used illicit stimulants at inclusion (initiation). CONCLUSION: High levels of ADHD symptoms are a feature that may promote both initiation and continuation of illicit stimulants use among university students. Our findings suggest that university students with high levels of ADHD symptoms may benefit from screening to help identify those at risk of illicit stimulants use.

6.
Stroke ; 53(4): 1263-1275, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34991336

RESUMO

BACKGROUND: Variants in the ring finger protein 213 (RNF213) gene are known to be associated with increased predisposition to cerebrovascular diseases development. Genomic studies have identified RNF213 as a major risk factor of Moyamoya disease in East Asian descendants. However, little is known about the RNF213 (ring finger protein 213) biological functions or its associated pathogenic mechanisms underlying Moyamoya disease. METHODS: To investigate RNF213 loss-of-function effect in endothelial cell, stable RNF213-deficient human cerebral endothelial cells were generated using the CRISPR-Cas9 genome editing technology. RESULTS: In vitro assays, using RNF213 knockout brain endothelial cells, showed clear morphological changes and increased blood-brain barrier permeability. Downregulation and delocalization of essential interendothelial junction proteins involved in the blood-brain barrier maintenance, such as PECAM-1 (platelet endothelial cell adhesion molecule-1), was also observed. Brain endothelial RNF213-deficient cells also showed an abnormal potential to transmigration of leukocytes and secreted high amounts of proinflammatory cytokines. CONCLUSIONS: Taken together, these results indicate that RNF213 could be a key regulator of cerebral endothelium integrity, whose disruption could be an early pathological mechanism leading to Moyamoya disease. This study also further reinforces the importance of blood-brain barrier integrity in the development of Moyamoya disease and other RNF213-associated diseases.


Assuntos
Adenosina Trifosfatases , Doença de Moyamoya , Ubiquitina-Proteína Ligases , Adenosina Trifosfatases/genética , Células Endoteliais/metabolismo , Endotélio , Predisposição Genética para Doença , Humanos , Doença de Moyamoya/patologia , Fatores de Transcrição , Ubiquitina-Proteína Ligases/genética
7.
J Chem Phys ; 156(15): 154901, 2022 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-35459308

RESUMO

We show that the slow viscoelastic response of a foam is that of a power-law fluid with a terminal relaxation. Investigations of the foam mechanics in creep and recovery tests reveal that the power-law contribution is fully reversible, indicative of a delayed elastic response. We demonstrate how this contribution fully accounts for the non-Maxwellian features observed in all tests, probing the linear mechanical response function. The associated power-law spectrum is consistent with soft glassy rheology of systems with mechanical noise temperatures just above the glass transition [Fielding et al., J. Rheol. 44, 323 (2000)] and originates from a combination of superdiffusive bubble dynamics and stress diffusion, as recently evidenced in simulations of coarsening foam [Hwang et al., Nat. Mater. 15, 1031 (2016)].

8.
Int J Mol Sci ; 23(6)2022 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-35328724

RESUMO

The success of dental implant treatment after tooth extraction is generally maximized by preserving the alveolar ridge using cell-free biomaterials. However, these treatments can be associated with inflammatory reactions, leading to additional bone volume loss hampering dental implant positioning. Our group developed a self-assembled bone-like substitute constituted of osteogenically induced human adipose-derived stromal/stem cells (hASCs). We hypothesized that a bone morphogenetic protein (BMP) supplementation could improve the in vitro osteogenic potential of the bone-like substitute, which would subsequently translate into enhanced alveolar bone healing after tooth extraction. ASCs displayed a better osteogenic response to BMP-9 than to BMP-2 in monolayer cell culture, as shown by higher transcript levels of the osteogenic markers RUNX2, osterix (OSX/SP7), and alkaline phosphatase after three and six days of treatment. Interestingly, BMP-9 treatment significantly increased OSX transcripts and alkaline phosphatase activity, as well as pro-angiogenic angiopoietin-1 gene expression, in engineered bone-like substitutes after 21 days of culture. Alveolar bone healing was investigated after molar extraction in nude rats. Microcomputed tomography and histological evaluations revealed similar, or even superior, global alveolar bone preservation when defects were filled with BMP-9-treated bone-like substitutes for ten weeks compared to a clinical-grade biomaterial, with adequate gingival re-epithelialization in the absence of resorption.


Assuntos
Substitutos Ósseos , Implantes Dentários , Fosfatase Alcalina/metabolismo , Processo Alveolar , Animais , Materiais Biocompatíveis , Fator 2 de Diferenciação de Crescimento , Humanos , Ratos , Extração Dentária/efeitos adversos , Microtomografia por Raio-X
9.
Proc Natl Acad Sci U S A ; 115(27): 6922-6927, 2018 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-29915026

RESUMO

The formation and kinetics of grain boundaries are closely related to the topological constraints imposed on their complex dislocation structure. Loop-shaped grain boundaries are unique structures to establish such a link because their overall topological "charge" is zero due to their null net Burgers vector. Here, we observe that a local rotational deformation of a 2D colloidal crystal with an optical vortex results in a grain boundary loop only if the product of its radius and misorientation exceeds a critical value. Above this value, the deformation is plastic and the grain boundary loop spontaneously shrinks at a rate that solely depends on this product, while otherwise, the deformation is elastically restored. We show that this elastic-to-plastic crossover is a direct consequence of the unique dislocation structure of grain boundary loops. At the critical value, the loop is structurally equivalent to the so-called "flower defect" and the shrinkage rate diverges. Our results thus reveal a general limit on the formation of grain boundary loops in 2D crystals and elucidate the central role of defects in both the onset of plasticity and the kinetics of grain boundaries.

10.
BMC Cardiovasc Disord ; 20(1): 499, 2020 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-33246420

RESUMO

BACKGROUND: In recent years, Ecological Momentary Assessment (EMA) has expanded rapidly in healthcare research but its application specifically to the field of cardiology has been limited. This study presents essential information concerning the feasibility and validity of EMA in patients with acute coronary syndrome. METHODS: Four months after a first-ever acute coronary syndrome, 47 patients completed EMA five times a day for seven consecutive days concerning their current activities, mood and perceived negativity or positivity of daily events. RESULTS: Compliance with the repeated electronic assessments was high, and no evidence was found for time-dependent biases such as fatigue or practice effects. The resulting EMA data were found to have high internal validity, high reliability when considering average scores, and low reliability when considering within-person variance. CONCLUSIONS: We found evidence for the feasibility and intrinsic validity of EMA in patients with acute coronary syndrome. Research examining daily life experiences, symptoms and therapeutic adherence in this population can be reinforced through the use of mobile technologies.


Assuntos
Atividades Cotidianas/psicologia , Síndrome Coronariana Aguda/diagnóstico , Afeto , Avaliação Momentânea Ecológica , Síndrome Coronariana Aguda/psicologia , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Fatores de Tempo
11.
Am J Pathol ; 188(5): 1132-1148, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29454750

RESUMO

Numerous clinical conditions can lead to organ fibrosis and functional failure. There is a great need for therapies that could effectively target pathophysiological pathways involved in fibrosis. GPR40 and GPR84 are G protein-coupled receptors with free fatty acid ligands and are associated with metabolic and inflammatory disorders. Although GPR40 and GPR84 are involved in diverse physiological processes, no evidence has demonstrated the relevance of GPR40 and GPR84 in fibrosis pathways. Using PBI-4050 (3-pentylbenzeneacetic acid sodium salt), a synthetic analog of a medium-chain fatty acid that displays agonist and antagonist ligand affinity toward GPR40 and GPR84, respectively, we uncovered an antifibrotic pathway involving these receptors. In experiments using Gpr40- and Gpr84-knockout mice in models of kidney fibrosis (unilateral ureteral obstruction, long-term post-acute ischemic injury, and adenine-induced chronic kidney disease), we found that GPR40 is protective and GPR84 is deleterious in these diseases. Moreover, through binding to GPR40 and GPR84, PBI-4050 significantly attenuated fibrosis in many injury contexts, as evidenced by the antifibrotic activity observed in kidney, liver, heart, lung, pancreas, and skin fibrosis models. Therefore, GPR40 and GPR84 may represent promising molecular targets in fibrosis pathways. We conclude that PBI-4050 is a first-in-class compound that may be effective for managing inflammatory and fibrosis-related diseases.


Assuntos
Nefropatias/patologia , Receptores Acoplados a Proteínas G/metabolismo , Insuficiência Renal Crônica/patologia , Animais , Fibrose/genética , Fibrose/metabolismo , Fibrose/patologia , Nefropatias/genética , Nefropatias/metabolismo , Camundongos , Camundongos Knockout , Receptores Acoplados a Proteínas G/genética , Insuficiência Renal Crônica/genética , Insuficiência Renal Crônica/metabolismo
12.
Clin Sci (Lond) ; 133(14): 1587-1602, 2019 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-31308217

RESUMO

PBI-4050 (3-pentylbenzenacetic acid sodium salt), a novel first-in-class orally active compound that has completed clinical Phases Ib and II in subjects with chronic kidney disease (CKD) and metabolic syndrome respectively, exerts antifibrotic effects in several organs via a novel mechanism of action, partly through activation of the G protein receptor 40 (GPR40) receptor. Here we evaluate the effects of PBI-4050 in both WT and Gpr40-/- mice on adenine-induced tubulointerstitial injury, anemia and activation of the unfolded protein response (UPR) pathway. Adenine-induced CKD was achieved in 8-week-old C57BL/6 mice fed a diet supplemented with 0.25% adenine. After 1 week, PBI-4050 or vehicle was administered daily by oral-gavage for 3 weeks. Gpr40-/- mice were also subjected to adenine-feeding, with or without PBI-4050 treatment. PBI-4050 improved renal function and urine concentrating ability. Anemia was present in adenine-fed mice, while PBI-4050 blunted these effects and led to significantly higher plasma erythropoietin (EPO) levels. Adenine-induced renal fibrosis, endoplasmic reticulum (ER) stress and apoptosis were significantly decreased by PBI-4050. In parallel, Gpr40-/- mice were more susceptible to adenine-induced fibrosis, renal function impairment, anemia and ER stress compared with WT mice. Importantly, PBI-4050 treatment in Gpr40-/- mice failed to reduce renal injury in this model. Taken together, PBI-4050 prevented adenine-induced renal injury while these beneficial effects were lost upon Gpr40 deletion. These data reinforce PBI-4050's use as a renoprotective therapy and identify GPR40 as a crucial mediator of its beneficial effects.


Assuntos
Acetatos/administração & dosagem , Adenina/efeitos adversos , Nefropatias/tratamento farmacológico , Rim/lesões , Receptores Acoplados a Proteínas G/metabolismo , Animais , Modelos Animais de Doenças , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Humanos , Rim/efeitos dos fármacos , Rim/metabolismo , Nefropatias/etiologia , Nefropatias/genética , Nefropatias/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores Acoplados a Proteínas G/genética
13.
Can J Surg ; 62(6): 488-498, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31782647

RESUMO

Summary: The Canadian Association of Chairs of Surgical Research was created in 2014, with representation from every departmental surgical research committee across Canada, to establish Canadian surgical research as a beacon for health care innovation and to propose solutions for the daily challenges facing surgeon-researchers. Our key mandate has been to identify challenges for surgeons and scientists performing research to prevent further erosion of this vital area of activity that benefits patients, health care service providers and Canadian society. This article outlines the findings of a nationwide survey sent to all members of departments of surgery across Canada, seeking input on current threats and potential solutions. The results suggest that surgical research in Canada is experiencing a decline in funding and an increase in challenges affecting research productivity of academic surgeons, such as pressures to be clinically active, unpredictable surgical schedules, growing administrative demands, and increasing complexity of patient populations. Although surgeons are productive in their research endeavours, institutional changes and sharing of best practices are needed to ensure sustainable growth of research programs.


Assuntos
Atitude do Pessoal de Saúde , Pesquisa Biomédica , Cirurgia Geral , Canadá , Humanos , Inquéritos e Questionários
14.
Rev Med Liege ; 74(3): 120-124, 2019 Mar.
Artigo em Francês | MEDLINE | ID: mdl-30897309

RESUMO

Pierre Robin sequence (PRS) is described as a triad of micrognathia, glossoptosis and cleft palate. This sequence may be isolated or associated with a genetic syndrome in half of the cases. Main complications affect respiratory function and the upper digestive tract. Respiratory obstruction can arise as soon as in the first hours of life and may be life-threatening if no early appropriate management is implemented. PRS is phenotypically variable and the required treatment varies accordingly: some patients will be relieved with prone positioning alone while others will benefit from nasopharyngeal tube, CPAP ("Continuous Positive Airway Pressure") or rarely surgery. In this article, we describe a clinical case and then discuss the available therapeutic strategies.


La séquence de Pierre Robin associe un rétrognatisme, une glossoptose et une fente palatine. Elle est isolée ou liée à un syndrome génétique dans la moitié des cas. Les complications sont principalement respiratoires et digestives. L'obstruction respiratoire peut se manifester dès les premières heures de vie et altérer la vie de l'enfant en l'absence d'une prise en charge précoce. Le degré de sévérité peut varier d'un enfant à l'autre et, alors que certains patients seront soulagés avec une position ventrale, d'autres nécessiteront un tube naso-pharyngé, une ventilation en pression positive continue (CPAP) ou, plus rarement, une intervention chirurgicale. Dans cet article, nous décrivons un cas clinique, puis nous rediscutons de l'ensemble des possibilités thérapeutiques.


Assuntos
Obstrução das Vias Respiratórias , Síndrome de Pierre Robin , Obstrução das Vias Respiratórias/terapia , Criança , Humanos , Síndrome de Pierre Robin/terapia
15.
Clin Immunol ; 195: 28-35, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30025819

RESUMO

Immunotherapy, using peptide-based cancer vaccines is being studied to assess its potential in breast cancer. Trials of HLA-restricted peptide vaccines have been difficult to enroll given HLA subtype restrictions. It is necessary to determine the prognostic significance of HLA-status in breast cancer if patients who are ineligible to receive a vaccine due to their HLA-status are used as controls. The impact of targeted tumor associated antigen expression, when it effects eligibility is also important. We examined control patients from two randomized phase II trials that tested HER2-peptide vaccines to determine the effect of HLA-A2 status and HER2 expression on disease-free survival. The analysis showed that HLA-A2-status does not affect disease-free survival, regardless of HER2 expression suggesting that HLA-A2 negative patients can be used as control patients. Additionally, HER2 over-expression was associated with a better disease-free survival in this population, underscoring the need for additional therapies in HER2 low-expressing breast cancer. ClinicalTrials.gov Identifier: NCT00524277.


Assuntos
Neoplasias da Mama/imunologia , Vacinas Anticâncer/imunologia , Antígeno HLA-A2/genética , Imunoterapia/métodos , Receptor ErbB-2/genética , Adulto , Idoso , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/mortalidade , Feminino , Seguimentos , Fator Estimulador de Colônias de Granulócitos e Macrófagos/imunologia , Humanos , Pessoa de Meia-Idade , Mutação/genética , Recidiva Local de Neoplasia , Receptor ErbB-2/imunologia , Projetos de Pesquisa , Risco , Análise de Sobrevida , Resultado do Tratamento , Vacinação , Vacinas de Subunidades Antigênicas
16.
J Pharmacol Exp Ther ; 367(1): 71-81, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30093459

RESUMO

Hepatic fibrosis is a major cause of morbidity and mortality for which there is currently no effective therapy. We previously showed that 2-(3-pentylphenyl)acetic acid (PBI-4050) is a dual G protein-coupled receptor GPR40 agonist/GPR84 antagonist that exerts antifibrotic, anti-inflammatory, and antiproliferative action. We evaluated PBI-4050 for the treatment of liver fibrosis in vivo and elucidated its mechanism of action on human hepatic stellate cells (HSCs). The antifibrotic effect of PBI-4050 was evaluated in carbon tetrachloride (CCl4)- and bile duct ligation-induced liver fibrosis rodent models. Treatment with PBI-4050 suppressed CCl4-induced serum aspartate aminotransferase levels, inflammatory marker nitric oxide synthase, epithelial to mesenchymal transition transcription factor Snail, and multiple profibrotic factors. PBI-4050 also decreased GPR84 mRNA expression in CCl4-induced injury, while restoring peroxisome proliferator-activated receptor γ (PPARγ) to the control level. Collagen deposition and α-smooth muscle actin (α-SMA) protein levels were also attenuated by PBI-4050 treatment in the bile duct ligation rat model. Transforming growth factor-ß-activated primary HSCs were used to examine the effect of PBI-4050 and its mechanism of action in vitro. PBI-4050 inhibited HSC proliferation by arresting cells in the G0/G1 cycle phase. Subsequent analysis demonstrated that PBI-4050 signals through a reduction of intracellular ATP levels, activation of liver kinase B1 (LKB1) and AMP-activated protein kinase (AMPK), and blockade of mammalian target of rapamycin (mTOR), resulting in reduced protein and mRNA levels of α-SMA and connective tissue growth factor and restored PPARγ mRNA expression. Our findings suggest that PBI-4050 may exert antifibrotic activity in the liver through a novel mechanism of action involving modulation of intracellular ATP levels and the LKB1/AMPK/mTOR pathway in stellate cells, and PBI-4050 may be a promising agent for treating liver fibrosis.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Trifosfato de Adenosina/metabolismo , Anti-Inflamatórios/farmacologia , Células Estreladas do Fígado/metabolismo , Cirrose Hepática/tratamento farmacológico , Proteínas Serina-Treonina Quinases/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Quinases Proteína-Quinases Ativadas por AMP , Animais , Tetracloreto de Carbono/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Células Estreladas do Fígado/efeitos dos fármacos , Humanos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Cirrose Hepática/metabolismo , Cirrose Hepática Experimental/induzido quimicamente , Cirrose Hepática Experimental/tratamento farmacológico , Cirrose Hepática Experimental/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , PPAR gama/metabolismo , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos
17.
J Surg Oncol ; 117(6): 1318-1322, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29355970

RESUMO

BACKGROUND AND OBJECTIVES: Pemetrexed is an appealing agent to use for cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (HIPEC). However, the optimal method of pemetrexed delivery still remains undefined. Using a murine model, we compared the use of open and closed abdomen techniques on the absorption of intraperitoneal (IP) pemetrexed in different compartments. METHODS: Eleven Sprague-Dawley rats were submitted to a fixed dose of IP pemetrexed (1000 mg/m2 ) at a perfusion temperature of 40°C during 25 min according to two techniques: open and closed. At the end of perfusion, samples in different compartments were harvested and the concentrations of pemetrexed were measured by high performance liquid chromatography. RESULTS: Absorption of IP pemetrexed in portal and systemic blood was significantly higher using the open compared to the closed abdomen technique (93.17 vs 52.50 µg/mL, P < 0.001) and (76.26 vs 51.65 µg/mL, P < 0.001), respectively. No difference was found between the two techniques on the peritoneal tissue concentration of pemetrexed (18.07 vs 19.17 µg/g, P = 0.51). CONCLUSION: Peritoneal absorption of pemetrexed is not modified by the use of either technique. However, systemic concentrations of pemetrexed increased using the open technique, suggesting it could increase systemic toxicity.


Assuntos
Cavidade Abdominal , Antineoplásicos/administração & dosagem , Modelos Animais de Doenças , Sistemas de Liberação de Medicamentos , Pemetrexede/administração & dosagem , Neoplasias Peritoneais/tratamento farmacológico , Animais , Masculino , Ratos , Ratos Sprague-Dawley
18.
Neuromodulation ; 21(7): 655-659, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29532593

RESUMO

OBJECTIVES: Stiff-person syndrome (SPS) is associated with axial rigidity superimposed on sustained muscle spasms. These symptoms commonly interfere with the performance of activities of daily living including ambulation. This retrospective case series evaluates the outcomes of screening tests and chronic infusion of intrathecal baclofen (ITB) in patients diagnosed with SPS treated in our spasticity clinic. MATERIALS AND METHODS: Patients were identified from an institutional review board-approved clinical registry of ITB therapy. Data from clinical encounters were extracted from the registry and from the patients' electronic medical record. All patients with medically refractory spasticity related to SPS screened with an ITB injection were included. In addition to pertinent demographic and clinical information, data from validated outcome measures routinely used in the clinic were collected: pain Numeric Rating Scale, Spasm Frequency Scale, lower extremity Modified Ashworth Scale (MAS), and Timed 25 Foot Walk. Outcomes data for chronic ITB infusion were assessed at early (<6 months) and late follow-up (6-12 months) visits after surgery. RESULTS: Nine patients were included, and seven received chronic ITB infusion. MAS scores were improved at early and late follow-up, and five patients experienced a reduction in pain scores. Walking performance remained stable in previously ambulatory patients. Four patients experienced complications related to ITB implantation, which resolved with medical or surgical treatment. CONCLUSION: Consistent with other case series, our results suggest that ITB is an effective therapy for medically intractable spasticity due to SPS, and symptom reduction can be achieved without compromising ambulation.


Assuntos
Baclofeno/uso terapêutico , Injeções Espinhais/métodos , Relaxantes Musculares Centrais/uso terapêutico , Rigidez Muscular Espasmódica/tratamento farmacológico , Adulto , Idoso , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Índice de Gravidade de Doença
19.
Am J Transplant ; 17(11): 2937-2944, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28707779

RESUMO

Immunosuppression in kidney transplant recipients with decreased graft function and severe histological vascular changes can be particularly challenging. Belatacept could be a valuable option, as a rescue therapy in this context. We report a retrospective case control study comparing a CNI to belatacept switch in 17 patients with vascular damage and low eGFR to a control group of 18 matched patients with CNI continuation. Belatacept switch was performed on average 51.5 months after kidney transplantation (6.2-198 months). There was no difference between the two groups regarding eGFR at inclusion, and 3 months before inclusion. In the "CNI to belatacept switch group," mean eGFR increased significantly from 23.5 ± 6.7 mL/min/1.73m2 on day 0, to 30.4 ± 9.1 mL/min/1.73 m2 on month 6 (p < 0.001) compared to the control group, in which no improvement was observed. These results were still significant on month 12. Two patients experienced biopsy-proven acute rejection. One was effectively treated without belatacept discontinuation. Two patients needed belatacept discontinuation for infection. In conclusion, the remplacement of CNI with belatacept in patients with decreased allograft function and vascular lesions is associated with an improvement in eGFR.


Assuntos
Abatacepte/uso terapêutico , Rejeição de Enxerto/prevenção & controle , Sobrevivência de Enxerto/efeitos dos fármacos , Falência Renal Crônica/cirurgia , Transplante de Rim/efeitos adversos , Doenças Vasculares/prevenção & controle , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Seguimentos , Taxa de Filtração Glomerular , Rejeição de Enxerto/etiologia , Rejeição de Enxerto/patologia , Humanos , Imunossupressores/uso terapêutico , Testes de Função Renal , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Doenças Vasculares/etiologia , Doenças Vasculares/patologia , Adulto Jovem
20.
J Immunol ; 195(11): 5393-403, 2015 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-26491199

RESUMO

The MAP3 kinase, TAK1, is known to act upstream of IKK and MAPK cascades in several cell types, and is typically activated in response to cytokines (e.g., TNF, IL-1) and TLR ligands. In this article, we report that in human neutrophils, TAK1 can also be activated by different classes of inflammatory stimuli, namely, chemoattractants and growth factors. After stimulation with such agents, TAK1 becomes rapidly and transiently activated. Blocking TAK1 kinase activity with a highly selective inhibitor (5z-7-oxozeaenol) attenuated the inducible phosphorylation of ERK occurring in response to these stimuli but had little or no effect on that of p38 MAPK or PI3K. Inhibition of TAK1 also impaired MEKK3 (but not MEKK1) activation by fMLF. Moreover, both TAK1 and the MEK/ERK module were found to influence inflammatory cytokine expression and release in fMLF- and GM-CSF-activated neutrophils, whereas the PI3K pathway influenced this response independently of TAK1. Besides cytokine production, other responses were found to be under TAK1 control in neutrophils stimulated with chemoattractants and/or GM-CSF, namely, delayed apoptosis and leukotriene biosynthesis. Our data further emphasize the central role of TAK1 in controlling signaling cascades and functional responses in primary neutrophils, making it a promising target for therapeutic intervention in view of the foremost role of neutrophils in several chronic inflammatory conditions.


Assuntos
Inflamação/imunologia , MAP Quinase Quinase Quinases/metabolismo , Sistema de Sinalização das MAP Quinases/imunologia , Neutrófilos/imunologia , Apoptose/efeitos dos fármacos , Células Cultivadas , Ativação Enzimática , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Humanos , Leucotrienos/biossíntese , MAP Quinase Quinase Quinase 1/metabolismo , MAP Quinase Quinase Quinase 3/metabolismo , MAP Quinase Quinase Quinases/antagonistas & inibidores , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , N-Formilmetionina Leucil-Fenilalanina/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação/efeitos dos fármacos , Zearalenona/análogos & derivados , Zearalenona/farmacologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
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