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1.
World J Radiol ; 16(1): 1-8, 2024 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-38312349

RESUMO

Anti-N-methyl-D-aspartate receptor-associated encephalitis (NMDARE) is a rare immune-mediated neuroinflammatory condition characterized by the rapid onset of neuropsychiatric symptoms and autonomic dysfunction. The mechanism of pathogenesis remains incompletely understood, but is thought to be related to antibodies targeting the GluN1 subunit of the NMDA receptor with resultant downstream dysregulation of dopaminergic pathways. Young adults are most frequently affected; the median age at diagnosis is 21 years. There is a strong female predilection with a female sex predominance of 4:1. NMDARE often develops as a paraneoplastic process and is most commonly associated with ovarian teratoma. However, NMDARE has also been described in patients with small cell lung cancer, clear cell renal carcinoma, and other benign and malignant neoplasms. Diagnosis is based on correlation of the clinical presentation, electroencephalography, laboratory studies, and imaging. Computed tomography, positron emission tomography, and magnetic resonance imaging are essential to identify an underlying tumor, exclude clinicopathologic mimics, and predict the likelihood of long-term functional impairment. Nuclear imaging may be of value for prognostication and to assess the response to therapy. Treatment may involve high-dose corticosteroids, intravenous immunoglobulin, and plasma exchange. Herein, we review the hallmark clinicopathologic features and imaging findings of this rare but potentially devastating condition and summarize diagnostic criteria, treatment regimens, and proposed pathogenetic mechanisms.

2.
Dev Dyn ; 252(8): 1077-1095, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36880501

RESUMO

Neural crest cells (NCCs) are highly motile, multipotent, embryonic cells that delaminate from the dorsal edges of the neural tube. NCCs follow stereotypical long-range migratory pathways to reach target organs during development, where they give rise to multiple derivatives. The identification of reservoirs of neural crest stem cells that persist to adulthood has recently aroused renewed interest in the biology of NCCs. In this context, several recent studies have demonstrated the essential role of the metabolic kinase LKB1 in NCC establishment. This review surveys how LKB1 governs the formation and maintenance of several neural crest derivatives, including facial bones, melanocytes, Schwann cells, and the enteric nervous system. We also detail the underlying molecular mechanisms that involve downstream effectors of LKB1, in particular the contribution of the AMPK-mTOR signaling pathway to both polarity and metabolic processes. Collectively, these recent discoveries open promising perspectives for new therapeutic applications for the treatment of neural crest disorders.


Assuntos
Crista Neural , Células-Tronco Neurais , Crista Neural/metabolismo , Transdução de Sinais , Tubo Neural , Células de Schwann , Movimento Celular/fisiologia , Diferenciação Celular
3.
J Ren Care ; 49(4): 278-287, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36210458

RESUMO

BACKGROUND: Nurse practitioners (NP) have an expanded scope of practice beyond that of a registered nurse. In kidney care, nephrology NP can manage patients at various points along the chronic kidney disease (CKD) trajectory. OBJECTIVES: To profile the characteristics, service patterns, and domains of practice of nephrology NP in Australia. DESIGN: A cross-sectional online secure survey. PARTICIPANTS: Nephrology NP (NP students) who were members of the Renal Society of Australasia and working in Australia (n = 73). MEASUREMENTS: Data collected were demographic and practice characteristics, and domains of practice (using the modified Strong Model of Advanced Practice). The survey also sought qualitative perspectives of the enablers and barriers to sustainability nurse practitioner healthcare delivery services. RESULTS: Nephrology NP (n = 45) primarily worked in adult services, managing those receiving haemodialysis, peritoneal dialysis, or patients with earlier grades of CKD. Providing direct comprehensive care was the dominant domain of advanced practice although administrative activities took up considerable time each week. Support from nurse leaders and medical colleagues was identified as key enablers for sustainability of these services whereas succession planning, and workload were the main barriers. CONCLUSIONS: This study found a highly qualified, experienced but older nephrology nurse practitioner workforce who provide an additional model of health service delivery which can meet the growing CKD burden. Internationally, this level of nurse provides an opportunity for a career pathway to maintain nurses in direct clinical roles and to expand the nephrology nursing workforce.


Assuntos
Nefrologia , Profissionais de Enfermagem , Insuficiência Renal Crônica , Adulto , Humanos , Estudos Transversais , Austrália , Insuficiência Renal Crônica/terapia , Papel do Profissional de Enfermagem
4.
J Med Chem ; 65(24): 16290-16312, 2022 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-36469401

RESUMO

Dual leucine zipper kinase (DLK) and leucine zipper-bearing kinase (LZK) are regulators of neuronal degeneration and axon growth. Therefore, there is a considerable interest in developing DLK/LZK inhibitors for neurodegenerative diseases. Herein, we use ligand- and structure-based drug design approaches for identifying novel amino-pyrazine inhibitors of DLK/LZK. DN-1289 (14), a potent and selective dual DLK/LZK inhibitor, demonstrated excellent in vivo plasma half-life across species and is anticipated to freely penetrate the central nervous system with no brain impairment based on in vivo rodent pharmacokinetic studies and human in vitro transporter data. Proximal target engagement and disease relevant pathway biomarkers were also favorably regulated in an in vivo model of amyotrophic lateral sclerosis.


Assuntos
Esclerose Lateral Amiotrófica , Doenças Neurodegenerativas , Humanos , Esclerose Lateral Amiotrófica/tratamento farmacológico , Esclerose Lateral Amiotrófica/metabolismo , Zíper de Leucina , MAP Quinase Quinase Quinases , Sistema Nervoso Central/metabolismo , Encéfalo/metabolismo , Doenças Neurodegenerativas/metabolismo
5.
J Immunother Cancer ; 9(12)2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34916256

RESUMO

BACKGROUND: Glypican-3 (GPC-3) is an oncofetal protein that is highly expressed in various solid tumors, but rarely expressed in healthy adult tissues and represents a rational target of particular relevance in hepatocellular carcinoma (HCC). Autologous chimeric antigen receptor (CAR) αß T cell therapies have established significant clinical benefit in hematologic malignancies, although efficacy in solid tumors has been limited due to several challenges including T cell homing, target antigen heterogeneity, and immunosuppressive tumor microenvironments. Gamma delta (γδ) T cells are highly cytolytic effectors that can recognize and kill tumor cells through major histocompatibility complex (MHC)-independent antigens upregulated under stress. The Vδ1 subset is preferentially localized in peripheral tissue and engineering with CARs to further enhance intrinsic antitumor activity represents an attractive approach to overcome challenges for conventional T cell therapies in solid tumors. Allogeneic Vδ1 CAR T cell therapy may also overcome other hurdles faced by allogeneic αß T cell therapy, including graft-versus-host disease (GvHD). METHODS: We developed the first example of allogeneic CAR Vδ1 T cells that have been expanded from peripheral blood mononuclear cells (PBMCs) and genetically modified to express a 4-1BB/CD3z CAR against GPC-3. The CAR construct (GPC-3.CAR/secreted interleukin-15 (sIL)-15) additionally encodes a constitutively-secreted form of IL-15, which we hypothesized could sustain proliferation and antitumor activity of intratumoral Vδ1 T cells expressing GPC-3.CAR. RESULTS: GPC-3.CAR/sIL-15 Vδ1 T cells expanded from PBMCs on average 20,000-fold and routinely reached >80% purity. Expanded Vδ1 T cells showed a primarily naïve-like memory phenotype with limited exhaustion marker expression and displayed robust in vitro proliferation, cytokine production, and cytotoxic activity against HCC cell lines expressing low (PLC/PRF/5) and high (HepG2) GPC-3 levels. In a subcutaneous HepG2 mouse model in immunodeficient NSG mice, GPC-3.CAR/sIL-15 Vδ1 T cells primarily accumulated and proliferated in the tumor, and a single dose efficiently controlled tumor growth without evidence of xenogeneic GvHD. Importantly, compared with GPC-3.CAR Vδ1 T cells lacking sIL-15, GPC-3.CAR/sIL-15 Vδ1 T cells displayed greater proliferation and resulted in enhanced therapeutic activity. CONCLUSIONS: Expanded Vδ1 T cells engineered with a GPC-3 CAR and sIL-15 represent a promising platform warranting further clinical evaluation as an off-the-shelf treatment of HCC and potentially other GPC-3-expressing solid tumors.


Assuntos
Carcinoma Hepatocelular/terapia , Glipicanas/imunologia , Imunoterapia Adotiva/métodos , Interleucina-15/imunologia , Neoplasias Hepáticas/terapia , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Receptores de Antígenos Quiméricos/imunologia , Animais , Apoptose , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/imunologia , Carcinoma Hepatocelular/patologia , Proliferação de Células , Feminino , Humanos , Leucócitos Mononucleares , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/patologia , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Genome Biol ; 21(1): 271, 2020 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-33148332

RESUMO

BACKGROUND: Metastasis is the primary cause of cancer mortality accounting for 90% of cancer deaths. Our understanding of the molecular mechanisms driving metastasis is rudimentary. RESULTS: We perform whole exome sequencing (WES), RNA sequencing, methylation microarray, and immunohistochemistry (IHC) on 8 pairs of non-small cell lung cancer (NSCLC) primary tumors and matched distant metastases. Furthermore, we analyze published WES data from 35 primary NSCLC and metastasis pairs, and transcriptomic data from 4 autopsy cases with metastatic NSCLC and one metastatic lung cancer mouse model. The majority of somatic mutations are shared between primary tumors and paired distant metastases although mutational signatures suggest different mutagenesis processes in play before and after metastatic spread. Subclonal analysis reveals evidence of monoclonal seeding in 41 of 42 patients. Pathway analysis of transcriptomic data reveals that downregulated pathways in metastases are mainly immune-related. Further deconvolution analysis reveals significantly lower infiltration of various immune cell types in metastases with the exception of CD4+ T cells and M2 macrophages. These results are in line with lower densities of immune cells and higher CD4/CD8 ratios in metastases shown by IHC. Analysis of transcriptomic data from autopsy cases and animal models confirms that immunosuppression is also present in extracranial metastases. Significantly higher somatic copy number aberration and allelic imbalance burdens are identified in metastases. CONCLUSIONS: Metastasis is a molecularly late event, and immunosuppression driven by different molecular events, including somatic copy number aberration, may be a common characteristic of tumors with metastatic plasticity.


Assuntos
Terapia de Imunossupressão , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Metástase Neoplásica/genética , Animais , Carcinoma Pulmonar de Células não Pequenas/genética , Metilação de DNA , Modelos Animais de Doenças , Regulação Neoplásica da Expressão Gênica , Genômica , Humanos , Imuno-Histoquímica , Camundongos , Mutação , Transcriptoma , Sequenciamento do Exoma
8.
Neuron ; 105(5): 837-854.e9, 2020 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-31902528

RESUMO

Loss-of-function (LOF) variants of TREM2, an immune receptor expressed in microglia, increase Alzheimer's disease risk. TREM2 senses lipids and mediates myelin phagocytosis, but its role in microglial lipid metabolism is unknown. Combining chronic demyelination paradigms and cell sorting with RNA sequencing and lipidomics, we find that wild-type microglia acquire a disease-associated transcriptional state, while TREM2-deficient microglia remain largely homeostatic, leading to neuronal damage. TREM2-deficient microglia phagocytose myelin debris but fail to clear myelin cholesterol, resulting in cholesteryl ester (CE) accumulation. CE increase is also observed in APOE-deficient glial cells, reflecting impaired brain cholesterol transport. This finding replicates in myelin-treated TREM2-deficient murine macrophages and human iPSC-derived microglia, where it is rescued by an ACAT1 inhibitor and LXR agonist. Our studies identify TREM2 as a key transcriptional regulator of cholesterol transport and metabolism under conditions of chronic myelin phagocytic activity, as TREM2 LOF causes pathogenic lipid accumulation in microglia.


Assuntos
Encéfalo/metabolismo , Colesterol/metabolismo , Macrófagos/metabolismo , Glicoproteínas de Membrana/genética , Microglia/metabolismo , Bainha de Mielina/metabolismo , Fagocitose/genética , Receptores Imunológicos/genética , Acetil-CoA C-Acetiltransferase/antagonistas & inibidores , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Animais , Ésteres do Colesterol/metabolismo , Modelos Animais de Doenças , Citometria de Fluxo , Humanos , Células-Tronco Pluripotentes Induzidas , Metabolismo dos Lipídeos/genética , Lipidômica , Receptores X do Fígado/agonistas , Camundongos , Camundongos Knockout , Camundongos Knockout para ApoE , RNA-Seq
9.
Cell ; 178(4): 795-806.e12, 2019 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-31398337

RESUMO

Most patients diagnosed with resected pancreatic adenocarcinoma (PDAC) survive less than 5 years, but a minor subset survives longer. Here, we dissect the role of the tumor microbiota and the immune system in influencing long-term survival. Using 16S rRNA gene sequencing, we analyzed the tumor microbiome composition in PDAC patients with short-term survival (STS) and long-term survival (LTS). We found higher alpha-diversity in the tumor microbiome of LTS patients and identified an intra-tumoral microbiome signature (Pseudoxanthomonas-Streptomyces-Saccharopolyspora-Bacillus clausii) highly predictive of long-term survivorship in both discovery and validation cohorts. Through human-into-mice fecal microbiota transplantation (FMT) experiments from STS, LTS, or control donors, we were able to differentially modulate the tumor microbiome and affect tumor growth as well as tumor immune infiltration. Our study demonstrates that PDAC microbiome composition, which cross-talks to the gut microbiome, influences the host immune response and natural history of the disease.


Assuntos
Carcinoma Ductal Pancreático/microbiologia , Carcinoma Ductal Pancreático/mortalidade , Microbioma Gastrointestinal , Neoplasias Pancreáticas/microbiologia , Neoplasias Pancreáticas/mortalidade , Adulto , Idoso , Animais , Bactérias/classificação , Linhagem Celular Tumoral , Estudos de Coortes , Transplante de Microbiota Fecal , Fezes/microbiologia , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , RNA Ribossômico 16S/genética , Análise de Sequência de RNA , Taxa de Sobrevida
10.
Sci Adv ; 5(7): eaau5106, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31328154

RESUMO

Metabolic processes underlying the development of the neural crest, an embryonic population of multipotent migratory cells, are poorly understood. Here, we report that conditional ablation of the Lkb1 tumor suppressor kinase in mouse neural crest stem cells led to intestinal pseudo-obstruction and hind limb paralysis. This phenotype originated from a postnatal degeneration of the enteric nervous ganglia and from a defective differentiation of Schwann cells. Metabolomic profiling revealed that pyruvate-alanine conversion is enhanced in the absence of Lkb1. Mechanistically, inhibition of alanine transaminases restored glial differentiation in an mTOR-dependent manner, while increased alanine level directly inhibited the glial commitment of neural crest cells. Treatment with the metabolic modulator AICAR suppressed mTOR signaling and prevented Schwann cell and enteric defects of Lkb1 mutant mice. These data uncover a link between pyruvate-alanine cycling and the specification of glial cell fate with potential implications in the understanding of the molecular pathogenesis of neural crest diseases.


Assuntos
Alanina/metabolismo , Crista Neural/citologia , Crista Neural/metabolismo , Proteínas Serina-Treonina Quinases/genética , Ácido Pirúvico/metabolismo , Proteínas Quinases Ativadas por AMP , Animais , Diferenciação Celular/genética , Metabolismo Energético , Sistema Nervoso Entérico , Inativação Gênica , Melanócitos/metabolismo , Camundongos , Camundongos Knockout , Mitocôndrias/metabolismo , Degeneração Neural/etiologia , Degeneração Neural/metabolismo , Degeneração Neural/patologia , Neuroglia/citologia , Neuroglia/metabolismo , Doenças do Sistema Nervoso Periférico/etiologia , Doenças do Sistema Nervoso Periférico/metabolismo , Doenças do Sistema Nervoso Periférico/patologia , Fenótipo , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de Sinais
11.
Br J Cancer ; 118(12): 1596-1608, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29795310

RESUMO

BACKGROUND: While lung adenocarcinoma patients can somewhat benefit from anti-angiogenic therapies, patients with squamous cell lung carcinoma (SQLC) cannot. The reasons for this discrepancy remain largely unknown. Soluble VEGF receptor-1, namely sVEGFR1-i13, is a truncated splice variant of the cell membrane-spanning VEGFR1 that has no transmembrane or tyrosine kinase domain. sVEGFR1-i13 is mainly viewed as an anti-angiogenic factor which counteracts VEGF-A/VEGFR signalling in endothelial cells. However, its role in tumour cells is poorly known. METHODS: mRNA and protein status were analysed by Real-Time qPCR, western blotting, ELISA assay, proximity ligation assay or immunohistochemistry in human tumour cell lines, murine tumourgrafts and non small cell lung carcinoma patients samples. RESULTS: We show that anti-angiogenic therapies specifically increase the levels of sVEGFR1-i13 in SQLC cell lines and chemically induced SQLC murine tumourgrafts. At the molecular level, we characterise a sVEGFR1-i13/ß1 integrin/VEGFR autocrine loop which determines whether SQLC cells proliferate or go into apoptosis, in response to anti-angiogenic therapies. Furthermore, we show that high levels of both sVEGFR1-i13 and ß1 integrin mRNAs and proteins are associated with advanced stages in SQLC patients and with a poor clinical outcome in patients with early stage SQLC. CONCLUSIONS: Overall, these results reveal an unexpected pro-tumoural function of sVEGFR1-i13 in SQLC tumour cells, which contributes to their progression and escape from anti-angiogenic therapies. These data might help to understand why some SQLC patients do not respond to anti-angiogenic therapies.


Assuntos
Inibidores da Angiogênese/farmacologia , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma de Células Escamosas/metabolismo , Integrina beta1/metabolismo , Neoplasias Pulmonares/metabolismo , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Animais , Comunicação Autócrina/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/irrigação sanguínea , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma de Células Escamosas/irrigação sanguínea , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/genética , Progressão da Doença , Humanos , Neoplasias Pulmonares/irrigação sanguínea , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Camundongos , Isoformas de Proteínas , Receptor Cross-Talk/efeitos dos fármacos , Células Tumorais Cultivadas , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/genética , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Oncotarget ; 9(19): 14764-14790, 2018 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-29599906

RESUMO

This manuscript follows a single patient with pancreatic adenocarcinoma for a five year period, detailing the clinical record, pathology, the dynamic evolution of molecular and cellular alterations as well as the responses to treatments with chemotherapies, targeted therapies and immunotherapies. DNA and RNA samples from biopsies and blood identified a dynamic set of changes in allelic imbalances and copy number variations in response to therapies. Organoid cultures established from biopsies over time were employed for extensive drug testing to determine if this approach was feasible for treatments. When an unusual drug response was detected, an extensive RNA sequencing analysis was employed to establish novel mechanisms of action of this drug. Organoid cell cultures were employed to identify possible antigens associated with the tumor and the patient's T-cells were expanded against one of these antigens. Similar and identical T-cell receptor sequences were observed in the initial biopsy and the expanded T-cell population. Immunotherapy treatment failed to shrink the tumor, which had undergone an epithelial to mesenchymal transition prior to therapy. A warm autopsy of the metastatic lung tumor permitted an extensive analysis of tumor heterogeneity over five years of treatment and surgery. This detailed analysis of the clinical descriptions, imaging, pathology, molecular and cellular evolution of the tumors, treatments, and responses to chemotherapy, targeted therapies, and immunotherapies, as well as attempts at the development of personalized medical treatments for a single patient should provide a valuable guide to future directions in cancer treatment.

13.
Psychiatr Serv ; 66(2): 112-4, 2015 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-25642607

RESUMO

Clinical evidence-based practices are strongly encouraged and commonly utilized in the behavioral health community. However, evidence-based practices that are related to quality improvement processes, such as Design for Six Sigma, are often not used in behavioral health care. This column describes the unique partnership formed between a behavioral health care provider in the greater Pittsburgh area, a nonprofit oversight and monitoring agency for behavioral health services, and academic researchers. The authors detail how the partnership used the multistep process outlined in Design for Six Sigma to completely redesign the provider's intake process. Implementation of the redesigned process increased access to care, decreased bad debt and uncollected funds, and improved cash flow--while consumer satisfaction remained high.


Assuntos
Comportamento Cooperativo , Prática Clínica Baseada em Evidências/organização & administração , Serviços de Saúde Mental/organização & administração , Organizações sem Fins Lucrativos/organização & administração , Qualidade da Assistência à Saúde/organização & administração , Prática Clínica Baseada em Evidências/normas , Acessibilidade aos Serviços de Saúde , Humanos , Serviços de Saúde Mental/normas , Organizações sem Fins Lucrativos/normas , Qualidade da Assistência à Saúde/normas , Universidades
14.
BMC Bioinformatics ; 15 Suppl 7: S4, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25077573

RESUMO

BACKGROUND: Currently available microRNA (miRNA) target prediction algorithms require the presence of a conserved seed match to the 5' end of the miRNA and limit the target sites to the 3' untranslated regions of mRNAs. However, it has been noted that these requirements may be too stringent, leading to a substantial number of missing targets. RESULTS: We have developed TargetS, a novel computational approach for predicting miRNA targets with the target sites located along entire gene sequences, which permits finding additional targets that are not located in the 3' un-translated regions. Our model is based on both canonical seed matching and non-canonical seed pairing, which discovers targets that allow one bit GU wobble. It does not rely on evolutionary conservation, so it allows the detection of species-specific miRNA-mRNA interactions and makes it suitable for analyzing un-conserved gene sequences. To test the performance of our approach, we have imported the widely used benchmark dataset revealing fold-changes in protein production corresponding to each of the five selected microRNAs. Compared to well-known miRNA target prediction tools, including TargetScanS, PicTar and MicroT_CDS, our method yields the highest sensitivity, while achieving a comparable level of accuracy. Human miRNA target predictions using our computational approach are available online at http://liubioinfolab.org/targetS/mirna.html CONCLUSIONS: A simple but powerful computational miRNA target prediction method is developed that is solely based on canonical and non-canonical seed matches without requiring evolutionary conservation of the target sites. Our method also expands the target search space to different gene regions, rather than limiting to 3'UTR only. This improves the sensitivity of miRNA target identification, while achieving a comparable accuracy with existing methods.


Assuntos
Genômica/métodos , MicroRNAs/metabolismo , RNA Mensageiro/genética , Algoritmos , Humanos , MicroRNAs/química , MicroRNAs/genética , Biossíntese de Proteínas , Proteínas/genética , Proteínas/metabolismo , RNA Mensageiro/química , RNA Mensageiro/metabolismo , Sequências Reguladoras de Ácido Nucleico
15.
Antimicrob Agents Chemother ; 58(8): 4915-9, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24867973

RESUMO

Sterile alpha motif- and histidine/aspartic acid domain-containing protein 1 (SAMHD1) limits HIV-1 replication by hydrolyzing deoxynucleoside triphosphates (dNTPs) necessary for reverse transcription. Nucleoside reverse transcriptase inhibitors (NRTIs) are components of anti-HIV therapies. We report here that SAMHD1 cleaves NRTI triphosphates (TPs) at significantly lower rates than dNTPs and that SAMHD1 depletion from monocytic cells affects the susceptibility of HIV-1 infections to NRTIs in complex ways that depend not only on the relative changes in dNTP and NRTI-TP concentrations but also on the NRTI activation pathways.


Assuntos
Didesoxinucleotídeos/metabolismo , Transcriptase Reversa do HIV/antagonistas & inibidores , HIV-1/efeitos dos fármacos , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Inibidores da Transcriptase Reversa/farmacologia , Adenina/análogos & derivados , Adenina/farmacologia , Linhagem Celular , Expressão Gênica , Genes Reporter , Transcriptase Reversa do HIV/genética , Transcriptase Reversa do HIV/metabolismo , HIV-1/enzimologia , Interações Hospedeiro-Patógeno , Humanos , Lamivudina/farmacologia , Luciferases/genética , Luciferases/metabolismo , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Monócitos/virologia , Proteínas Monoméricas de Ligação ao GTP/antagonistas & inibidores , Proteínas Monoméricas de Ligação ao GTP/genética , Organofosfonatos/farmacologia , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Proteína 1 com Domínio SAM e Domínio HD , Estavudina/farmacologia , Tenofovir , Replicação Viral/efeitos dos fármacos , Zidovudina/farmacologia
16.
Diabetes ; 63(10): 3199-209, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24789920

RESUMO

Type 2 diabetes (T2D) is hallmarked by insulin resistance, impaired insulin secretion, and increased hepatic glucose production. The worldwide increasing prevalence of T2D calls for efforts to understand its pathogenesis in order to improve disease prevention and management. Recent genome-wide association studies have revealed strong associations between the CDKN2A/B locus and T2D risk. The CDKN2A/B locus contains genes encoding cell cycle inhibitors, including p16(Ink4a), which have not yet been implicated in the control of hepatic glucose homeostasis. Here, we show that p16(Ink4a) deficiency enhances fasting-induced hepatic glucose production in vivo by increasing the expression of key gluconeogenic genes. p16(Ink4a) downregulation leads to an activation of PKA-CREB-PGC1α signaling through increased phosphorylation of PKA regulatory subunits. Taken together, these results provide evidence that p16(Ink4a) controls fasting glucose homeostasis and could as such be involved in T2D development.


Assuntos
Inibidor p16 de Quinase Dependente de Ciclina/genética , Jejum/metabolismo , Gluconeogênese/fisiologia , Fígado/metabolismo , Transdução de Sinais/fisiologia , Animais , Linhagem Celular , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Camundongos , Camundongos Knockout , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo , Fatores de Transcrição/metabolismo
17.
J Clin Invest ; 124(3): 1037-51, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24531544

RESUMO

The nuclear bile acid receptor farnesoid X receptor (FXR) is an important transcriptional regulator of bile acid, lipid, and glucose metabolism. FXR is highly expressed in the liver and intestine and controls the synthesis and enterohepatic circulation of bile acids. However, little is known about FXR-associated proteins that contribute to metabolic regulation. Here, we performed a mass spectrometry-based search for FXR-interacting proteins in human hepatoma cells and identified AMPK as a coregulator of FXR. FXR interacted with the nutrient-sensitive kinase AMPK in the cytoplasm of target cells and was phosphorylated in its hinge domain. In cultured human and murine hepatocytes and enterocytes, pharmacological activation of AMPK inhibited FXR transcriptional activity and prevented FXR coactivator recruitment to promoters of FXR-regulated genes. Furthermore, treatment with AMPK activators, including the antidiabetic biguanide metformin, inhibited FXR agonist induction of FXR target genes in mouse liver and intestine. In a mouse model of intrahepatic cholestasis, metformin treatment induced FXR phosphorylation, perturbed bile acid homeostasis, and worsened liver injury. Together, our data indicate that AMPK directly phosphorylates and regulates FXR transcriptional activity to precipitate liver injury under conditions favoring cholestasis.


Assuntos
Adenilato Quinase/metabolismo , Ácidos e Sais Biliares/biossíntese , Homeostase , Hipoglicemiantes/farmacologia , Metformina/farmacologia , Receptores Citoplasmáticos e Nucleares/metabolismo , Adenilato Quinase/antagonistas & inibidores , Sequência de Aminoácidos , Aminoimidazol Carboxamida/análogos & derivados , Aminoimidazol Carboxamida/farmacologia , Animais , Transporte Biológico , Células CACO-2 , Colestase Intra-Hepática/metabolismo , Colestase Intra-Hepática/patologia , Células Hep G2 , Humanos , Mucosa Intestinal/metabolismo , Intestinos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , Fosforilação , Regiões Promotoras Genéticas , Ligação Proteica , Processamento de Proteína Pós-Traducional , Receptores Citoplasmáticos e Nucleares/química , Ribonucleotídeos/farmacologia , Transdução de Sinais , Transativadores/metabolismo , Transcrição Gênica , Ativação Transcricional/efeitos dos fármacos
18.
J Clin Aesthet Dermatol ; 6(11): 32-8, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24307923

RESUMO

OBJECTIVE: To evaluate treating epidermal melasma using a 4% hydroquinone skin care system plus tretinoin 0.05% cream. DESIGN: Multicenter open-label study with all patients receiving above-mentioned treatment for up to 24 weeks. SETTING: Private dermatology and plastic surgery clinics and clinical research facilities. PARTICIPANTS: Thirty-seven adult females with moderate or marked epidermal melasma, melasma pigmentation of mild-to-marked intensity and Fitzpatrick skin type III to VI. MEASUREMENTS: Melasma severity melasma pigmentation intensity melasma improvement, patient satisfaction, quality-of-life measures, erythema, dryness, peeling, burning/stinging. RESULTS: No patient discontinued due to lack of efficacy or treatment-related adverse events. Treatment was associated with a significant reduction from baseline in melasma severity and melasma pigmentation intensity from Week 4 onward (P≤0.001), and 100 percent of patients showed improvement from Week 8 onward. At Week 24, 100 percent of patients were "satisfied" or "very satisfied" with the overall effectiveness of their treatment. Patients' quality of life also improved (e.g., the proportion of patients feeling embarrassed or self-conscious about their skin "a lot" or "very much" declined from 78 percent at baseline to four percent at Week 24). Mean and median scores for erythema, dryness, peeling, and burning/stinging did not exceed trace levels. CONCLUSION: Treating moderate-to-severe melasma using the 4% hydroquinone skin care system plus 0.05% tretinoin can significantly reduce the severity of melasma and the intensity of melasma pigmentation within four weeks. Treatment was generally well tolerated and associated with an improved quality of life and high levels of patient satisfaction.

19.
Hum Fertil (Camb) ; 16(4): 252-7, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24171651

RESUMO

The aim of this study was to determine the satisfaction among subfertile women of a fertility awareness-based approach, including hormonal therapy to achieve a pregnancy by natural conception. Eighty four women attending a natural fertility service completed a postal questionnaire exploring (1) the acceptability of the sympto-thermal method and (2) the acceptability of using hormone support. Acceptability rates for the fertility charting, clinical service and clinical care were 64.9-91.6%. Acceptability rates were higher in women who did conceive or had experienced past recurrent miscarriages. Taking hormonal luteal support, by any method, was more acceptable for women over 35 years compared to those under 35 years (100% vs. 69.4%, p = 0.014). Vaginal pessaries were the preferred route of administration. The use of a fertility awareness-based method appears to be acceptable amongst subfertile women intending to conceive naturally. Most women using such a method for conception would be open to the use of hormonal support during the fertility cycle or early pregnancy.


Assuntos
Fertilidade , Conhecimentos, Atitudes e Prática em Saúde , Hormônios/uso terapêutico , Infertilidade Feminina/terapia , Adulto , Temperatura Corporal , Feminino , Humanos , Satisfação do Paciente , Gravidez , Inquéritos e Questionários
20.
Atherosclerosis ; 229(1): 42-51, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23672878

RESUMO

BACKGROUND: Atherosclerosis and vascular calcification are major contributors to cardiovascular morbidity and mortality among chronic kidney disease patients. The mevalonate pathway may play a role in this vascular pathology. Farnesyltransferase inhibitors such as R115777 block one branch of mevalonate pathway. We studied the effects of farnesyltransferase inhibitor R115777 on vascular disease in apolipoprotein E deficient mice with chronic renal failure and on mineral deposition in vitro. METHODS AND RESULTS: Female uremic and non-uremic apolipoprotein E deficient mice were randomly assigned to four groups and treated with either farnesyltransferase inhibitor R115777 or vehicle. Farnesyltransferase inhibitor R115777 inhibited protein prenylation in mice with chronic renal failure. It decreased aortic atheromatous lesion area and calcification in these animals, and reduced vascular nitrotyrosine expression and total collagen as well as collagen type I content. Proteomic analysis revealed that farnesyltransferase inhibitor corrected the chronic renal failure-associated increase in serum apolipoprotein IV and α globin, and the chronic renal failure-associated decrease in serum fetuin A. Farnesyltransferase inhibitor further inhibited type I collagen synthesis and reduced mineral deposition in vascular smooth muscle cells in vitro, probably involving Ras-Raf pathway. CONCLUSIONS: We show for the first time that farnesyltransferase inhibition slows vascular disease progression in chronic renal failure by both indirect systemic and direct local actions. This beneficial effect was mediated via a reduction in oxidative stress and favorable changes in vasoprotective peptides.


Assuntos
Aterosclerose/prevenção & controle , Inibidores Enzimáticos/farmacologia , Farnesiltranstransferase/antagonistas & inibidores , Quinolonas/farmacologia , Uremia/tratamento farmacológico , Calcificação Vascular/prevenção & controle , Animais , Aorta/metabolismo , Aorta/patologia , Apolipoproteínas E/genética , Apoptose , Aterosclerose/metabolismo , Aterosclerose/patologia , Proteínas Sanguíneas/análise , Proteínas Sanguíneas/metabolismo , Peso Corporal , Colágeno Tipo I/metabolismo , Feminino , Falência Renal Crônica/tratamento farmacológico , Falência Renal Crônica/metabolismo , Falência Renal Crônica/patologia , Fígado/metabolismo , Macrófagos/patologia , Ácido Mevalônico/metabolismo , Camundongos , Camundongos Knockout , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patologia , Prenilação/efeitos dos fármacos , Distribuição Aleatória , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Tirosina/análogos & derivados , Tirosina/metabolismo , Uremia/metabolismo , Uremia/patologia , Calcificação Vascular/metabolismo , Calcificação Vascular/patologia
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