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1.
J Ultrasound Med ; 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39351866

RESUMO

OBJECTIVES: Neuromuscular respiratory failure after cervical spinal cord injury (cSCI) can lead to dependence on an invasive mechanical ventilator. Ventilator-free breathing after cSCI is associated with improved morbidity, mortality, and quality of life. We investigated the use of diaphragm muscle ultrasound to predict ventilator weaning outcomes after cSCI. METHODS: This is a retrospective case series conducted at a university-affiliated freestanding inpatient rehabilitation facility. We identified patients with cSCI who had a tracheostomy and were dependent on an invasive mechanical ventilator at the time of admission to inpatient rehabilitation. A diaphragm muscle ultrasound was performed, which included measurements of the thickness of the diaphragm and a calculation of the thickening ratio (TR), which reflects diaphragm muscle contraction. The primary outcome measure was the need for mechanical ventilation at time of discharge from the inpatient rehabilitation facility. Successful ventilator weaning was defined as either daytime or full 24-hour ventilator-free breathing. RESULTS: Of the 21 patients enrolled, 11 (52%) were able to wean successfully (partially or fully) from the ventilator. Of the ultrasound measurements that were taken, the TR was the optimal predictor for ventilator weaning outcomes. A threshold of TR ≥ 1.2 as the maximum hemidiaphragm measurement had a sensitivity of 1.0 and specificity of 0.90 for predicting ventilator weaning. CONCLUSION: Normal diaphragm contractility (TR ≥ 1.2) as determined by diaphragm muscle ultrasound is a strong positive predictor for successful ventilator weaning in patients with cSCI. Utilizing diaphragm ultrasound, rehabilitation physicians can set precision rehabilitation goals regarding ventilator weaning for inpatients with respiratory failure after cSCI, potentially improving both outcomes and quality of life.

2.
Nature ; 614(7946): 144-152, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36509107

RESUMO

Cell adhesion molecules are ubiquitous in multicellular organisms, specifying precise cell-cell interactions in processes as diverse as tissue development, immune cell trafficking and the wiring of the nervous system1-4. Here we show that a wide array of synthetic cell adhesion molecules can be generated by combining orthogonal extracellular interactions with intracellular domains from native adhesion molecules, such as cadherins and integrins. The resulting molecules yield customized cell-cell interactions with adhesion properties that are similar to native interactions. The identity of the intracellular domain of the synthetic cell adhesion molecules specifies interface morphology and mechanics, whereas diverse homotypic or heterotypic extracellular interaction domains independently specify the connectivity between cells. This toolkit of orthogonal adhesion molecules enables the rationally programmed assembly of multicellular architectures, as well as systematic remodelling of native tissues. The modularity of synthetic cell adhesion molecules provides fundamental insights into how distinct classes of cell-cell interfaces may have evolved. Overall, these tools offer powerful abilities for cell and tissue engineering and for systematically studying multicellular organization.


Assuntos
Moléculas de Adesão Celular , Comunicação Celular , Biologia Sintética , Caderinas/química , Adesão Celular , Moléculas de Adesão Celular/química , Moléculas de Adesão Celular/metabolismo , Integrinas/química , Biologia Sintética/métodos , Domínios Proteicos , Sítios de Ligação , Engenharia Celular
3.
Science ; 370(6520): 1099-1104, 2020 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-33243890

RESUMO

Living cells often identify their correct partner or target cells by integrating information from multiple receptors, achieving levels of recognition that are difficult to obtain with individual molecular interactions. In this study, we engineered a diverse library of multireceptor cell-cell recognition circuits by using synthetic Notch receptors to transcriptionally interconnect multiple molecular recognition events. These synthetic circuits allow engineered T cells to integrate extra- and intracellular antigen recognition, are robust to heterogeneity, and achieve precise recognition by integrating up to three different antigens with positive or negative logic. A three-antigen AND gate composed of three sequentially linked receptors shows selectivity in vivo, clearing three-antigen tumors while ignoring related two-antigen tumors. Daisy-chaining multiple molecular recognition events together in synthetic circuits provides a powerful way to engineer cellular-level recognition.


Assuntos
Comunicação Celular/imunologia , Engenharia Celular , Receptores de Antígenos Quiméricos/imunologia , Receptores Notch/imunologia , Linfócitos T/imunologia , Animais , Antígenos de Neoplasias/imunologia , Humanos , Camundongos , Receptores de Antígenos Quiméricos/genética , Receptores Notch/genética , Transcrição Gênica
4.
J Fish Biol ; 96(1): 83-91, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31664721

RESUMO

We examined the functional morphology of loach Misgurnus anguillicaudatus skin by using synchrotron X-ray micro-computed tomography (SR-µCT) and high-contrast staining using osmium tetroxide or phosphotungstic acid (PTA), which enhances the image contrast of soft tissues. The captured high-spatial resolution images revealed that the surface ornamentations were stuck in the basement membrane of the loach scales. The ornamentations consisting of grooves (radii) and ridges (circuli) that can move freely and bend flexibly. The cross-sectional lateral microstructures of flat, concave and convex loach skins were observed from a live image of loach skin obtained through dark-field optical coherence tomography (OCT) imaging. The thickness of loach skin was changed with varying empty space between the mucous-cell layer and the scales by bending motion of loach. In addition, through direct measurement of drag reduction of loach skin, the mucous layer was found to have a strong influence on the reduction of skin friction. The present results enhance the understanding of the functional morphologies of mucous layer of loach to secrete mucus for skin friction reduction.


Assuntos
Cipriniformes/fisiologia , Proteínas de Peixes/fisiologia , Muco/fisiologia , Fenômenos Fisiológicos da Pele , Pele/anatomia & histologia , Animais , Estudos Transversais , Proteínas de Peixes/genética , Fricção , Filogenia , Microtomografia por Raio-X
5.
Minerva Urol Nefrol ; 71(1): 72-78, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30037211

RESUMO

BACKGROUND: Even though the safety of the treatment for prostate cancer diagnosed by HoLEP has been reported, the diagnostic value of HoLEP for prostate cancer detection has not been confirmed. Therefore, we investigated the diagnostic potential of HoLEP for detecting prostate cancer. METHODS: Between December 2009 and October 2015, 359 patients (median age, 70.9 years; range, 66.2-74.8) were treated simultaneously with HoLEP and transrectal prostate needle biopsy (TPNB). Of these, 199 patients with a normal digital rectal examination and serum PSA concentration between 3.5 and 10.0 ng/mL were included in the study. Univariate and multivariate logistic regression analyses were performed to identify the predictive factor for prostate cancer detected by HoLEP. RESULTS: Median PSA, prostate volume and PSA density were 4.97 ng/mL (range, 4.20-6.70), 57.40 gm (range, 43.67-77.80) and 0.09 ng/mL2 (range, 0.07-0.12), respectively. Prostate cancer (Gleason score ≥6) was detected in 46 cases (23.1%). Of these, 26 (56.5%) were detected by HoLEP pathology, 11 (23.9%) by TPNB pathology, and 9 (19.6%) by both. Univariate and multivariate logistic regression analyses were performed in 179 patients, including benign prostatic hyperplasia patients (N=153, 76.9%) and patients with cancer detected by HoLEP pathology. PSA density was identified as an independent predictor of prostate cancer detected by HoLEP in gray-zone PSA. CONCLUSIONS: HoLEP is a viable modality for detecting prostate cancer in selected cases. PSA density was an independent predictor of prostate cancer detected by HoLEP in gray-zone PSA.


Assuntos
Lasers de Estado Sólido , Antígeno Prostático Específico/análise , Neoplasias da Próstata/diagnóstico por imagem , Idoso , Biópsia por Agulha , Humanos , Masculino , Gradação de Tumores , Hiperplasia Prostática/diagnóstico por imagem
6.
Cancer Sci ; 110(2): 629-638, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30457689

RESUMO

Nicotinamide adenine dinucleotide (NAD) exists in an oxidized form (NAD+ ) and a reduced form (NADH). NAD+ plays crucial roles in cancer metabolism, including in cellular signaling, energy production and redox regulation. However, it remains unclear whether NAD(H) pool size (NAD+ and NADH) could be used as biomarker for colon cancer progression. Here, we showed that the NAD(H) pool size and NAD+ /NADH ratio both increased during colorectal cancer (CRC) progression due to activation of the NAD+ salvage pathway mediated by nicotinamide phosphoribosyltransferase (NAMPT). The NAMPT expression was upregulated in adenoma and adenocarcinoma tissues from CRC patients. The NADH fluorescence intensity measured by two-photon excitation fluorescence (TPEF) microscopy was consistently increased in CRC cell lines, azoxymethane/dextran sodium sulfate (AOM/DSS)-induced CRC tissues and tumor tissues from CRC patients. The increases in the NAD(H) pool inhibited the accumulation of excessive reactive oxygen species (ROS) levels and FK866, a specific inhibitor of NAMPT, treatment decreased the CRC nodule size by increasing ROS levels in AOM/DSS mice. Collectively, our results suggest that NAMPT-mediated upregulation of the NAD(H) pool protects cancer cells against detrimental oxidative stress and that detecting NADH fluorescence by TPEF microscopy could be a potential method for monitoring CRC progression.


Assuntos
Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , NAD/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Adenoma/metabolismo , Adenoma/patologia , Animais , Linhagem Celular Tumoral , Colo/metabolismo , Colo/patologia , Progressão da Doença , Células HCT116 , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Estresse Oxidativo/fisiologia , Regulação para Cima/fisiologia
7.
J Bone Miner Res ; 33(10): 1729-1740, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29905973

RESUMO

Spinal cord injury (SCI) is associated with marked bone loss and an increased risk of fracture. We randomized 61 individuals with chronic SCI and low bone mass to receive either teriparatide 20 µg/d plus sham vibration 10 min/d (n = 20), placebo plus vibration 10 min/d (n = 20), or teriparatide 20 µg/d plus vibration 10 min/d (n = 21). Patients were evaluated for 12 months; those who completed were given the opportunity to participate in an open-label extension where all participants (n = 25) received teriparatide 20 µg/d for an additional 12 months and had the optional use of vibration (10 min/d). At the end of the initial 12 months, both groups treated with teriparatide demonstrated a significant increase in areal bone mineral density (aBMD) at the spine (4.8% to 5.5%). The increase in spine aBMD was consistent with a marked response in serum markers of bone metabolism (ie, CTX, P1NP, BSAP), but no treatment effect was observed at the hip. A small but significant increase (2.2% to 4.2%) in computed tomography measurements of cortical bone at the knee was observed in all groups after 12 months; however, the magnitude of response was not different amongst treatment groups and improvements to finite element-predicted bone strength were not observed. Teriparatide treatment after the 12-month extension resulted in further increases to spine aBMD (total increase from baseline 7.1% to 14.4%), which was greater in patients initially randomized to teriparatide. Those initially randomized to teriparatide also demonstrated 4.4% to 6.7% improvements in hip aBMD after the 12-month extension, while all groups displayed increases in cortical bone measurements at the knee. To summarize, teriparatide exhibited skeletal activity in individuals with chronic SCI that was not augmented by vibration stimulation. Without additional confirmatory data, the location-specific responses to teriparatide would not be expected to provide clinical benefit in this population. © 2018 American Society for Bone and Mineral Research.


Assuntos
Reabsorção Óssea/complicações , Reabsorção Óssea/tratamento farmacológico , Osso e Ossos/patologia , Osso e Ossos/fisiopatologia , Traumatismos da Medula Espinal/tratamento farmacológico , Traumatismos da Medula Espinal/fisiopatologia , Teriparatida/uso terapêutico , Vibração , Absorciometria de Fóton , Adulto , Biomarcadores/metabolismo , Reabsorção Óssea/diagnóstico por imagem , Reabsorção Óssea/fisiopatologia , Osso e Ossos/diagnóstico por imagem , Osso e Ossos/efeitos dos fármacos , Feminino , Análise de Elementos Finitos , Fraturas Ósseas/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/diagnóstico por imagem , Teriparatida/farmacologia , Tomografia Computadorizada por Raios X , Resultado do Tratamento
8.
Mol Pharm ; 12(9): 3399-407, 2015 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-26262434

RESUMO

Understanding the mechanistic basis of prodrug delivery and activation is critical for establishing species-specific prodrug sensitivities necessary for evaluating preclinical animal models and potential drug-drug interactions. Despite significant adoption of prodrug methodologies for enhanced pharmacokinetics, functional annotation of prodrug activating enzymes is laborious and often unaddressed. Activity-based protein profiling (ABPP) describes an emerging chemoproteomic approach to assay active site occupancy within a mechanistically similar enzyme class in native proteomes. The serine hydrolase enzyme family is broadly reactive with reporter-linked fluorophosphonates, which have shown to provide a mechanism-based covalent labeling strategy to assay the activation state and active site occupancy of cellular serine amidases, esterases, and thioesterases. Here we describe a modified ABPP approach using direct substrate competition to identify activating enzymes for an ethyl ester prodrug, the influenza neuraminidase inhibitor oseltamivir. Substrate-competitive ABPP analysis identified carboxylesterase 1 (CES1) as an oseltamivir-activating enzyme in intestinal cell homogenates. Saturating concentrations of oseltamivir lead to a four-fold reduction in the observed rate constant for CES1 inactivation by fluorophosphonates. WWL50, a reported carbamate inhibitor of mouse CES1, blocked oseltamivir hydrolysis activity in human cell homogenates, confirming CES1 is the primary prodrug activating enzyme for oseltamivir in human liver and intestinal cell lines. The related carbamate inhibitor WWL79 inhibited mouse but not human CES1, providing a series of probes for analyzing prodrug activation mechanisms in different preclinical models. Overall, we present a substrate-competitive activity-based profiling approach for broadly surveying candidate prodrug hydrolyzing enzymes and outline the kinetic parameters for activating enzyme discovery, ester prodrug design, and preclinical development of ester prodrugs.


Assuntos
Hidrolases de Éster Carboxílico/metabolismo , Inibidores Enzimáticos/farmacologia , Ésteres/farmacologia , Oseltamivir/farmacologia , Pró-Fármacos/farmacologia , Animais , Linhagem Celular , Humanos , Hidrólise , Mucosa Intestinal/metabolismo , Intestinos/efeitos dos fármacos , Cinética , Fígado/efeitos dos fármacos , Fígado/metabolismo , Camundongos , Especificidade por Substrato
10.
J Ren Nutr ; 22(1): 58-66, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21620727

RESUMO

OBJECTIVE: Vascular calcification (VC) scores determined by using simple plain radiographic films are known to be associated with coronary artery disease and mortality in patients undergoing hemodialysis (HD). Omega-3 fatty acid (FA) has been shown to reduce ectopic calcifications in an animal model, and it has also been shown that erythrocyte membrane omega-3 FA content is an independent discriminator of coronary artery disease. The present study was designed to demonstrate relations between VC scores and erythrocyte membrane FA contents in patients undergoing HD. DESIGN: A cross-sectional study was carried out. SETTING: The study was carried out at an outpatient hemodialysis unit at Dong-A University Hospital, Busan, Republic of Korea. PATIENTS: A total of 31 patients undergoing HD were recruited. Patients with significant malnutrition, a short duration of dialysis (<12 months), a history of recent infection, malignancy, or liver disease were excluded. MAIN OUTCOME MEASURES: Plain radiographic films of the feet, hands, pelvis, and lateral lumbar spine were examined and VC scores were determined using previously reported methods. Erythrocyte membrane FA contents were analyzed by gas chromatography. RESULTS: The erythrocyte membrane contents of eicosapentaenoic acid and docosahexaenoic acid were not found to be related with VC on simple plain radiographic films. However, erythrocyte membrane contents of oleic acid and total monounsaturated FA (MUFA) were significantly higher in patients with significant VC scores. Furthermore, erythrocyte membrane contents of MUFA and oleic acid were found to be negatively associated with high-density lipoprotein cholesterol level and positively associated with triglyceride level. CONCLUSION: Erythrocyte membrane contents of MUFA and oleic acid were found to be associated with VC scores determined using plain radiographs and with dyslipidemia in patients undergoing HD.


Assuntos
Membrana Eritrocítica/química , Ácidos Graxos/sangue , Diálise Renal , Calcificação Vascular/diagnóstico por imagem , Idoso , Doenças Cardiovasculares/complicações , HDL-Colesterol/sangue , Cromatografia Gasosa , Estudos Transversais , Ácidos Graxos Monoinsaturados/sangue , Ácidos Graxos Ômega-3/sangue , Feminino , Humanos , Falência Renal Crônica/sangue , Falência Renal Crônica/complicações , Falência Renal Crônica/terapia , Masculino , Pessoa de Meia-Idade , Ácido Oleico/sangue , Radiografia , Triglicerídeos/sangue , Calcificação Vascular/sangue
11.
Anticancer Drugs ; 22(8): 719-31, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21666438

RESUMO

Despite incremental progress in the treatment of pancreatic adenocarcinoma, the prognosis of patients remains poor. Here, we report the preclinical studies in pancreatic cancer cells that demonstrate the efficacy of triphendiol (NV-196, a synthetic isoflavene) both as a monotherapy and as a gemcitabine sensitizer. The in-vitro effects of triphendiol on the pancreatic cancer cell lines HPAC and MIAPaCa-2 were determined using cell proliferation, flow cytometry, and western blot analysis. The antiproliferative activity of triphendiol was also investigated in two xenograft models of pancreatic cancer (HPAC and MIAPaCa-2). As a monotherapy, triphendiol-inhibited cell proliferation-induced p53-independent G2/M cell cycle arrest and activation of the intrinsic (mitochondrial) apoptosis pathway. Triphendiol-induced apoptosis was caspase independent and death receptor independent, whereas cell necrosis was caspase mediated. Using combination index analysis, we have shown that pretreatment of pancreatic cancer cells with triphendiol enhanced the cytotoxic effect of gemcitabine, the standard of care used to treat advanced pancreatic cancer. In xenograft models of pancreatic cancer, the rate of tumor proliferation on mice coadministered with triphendiol and gemcitabine was significantly reduced when compared with the corresponding tumor proliferation rates from the respective monotherapy-control and vehicle-control groups. Triphendiol was recently granted Investigational New Drug status by the US Food and Drug Administration. These data justify the commencement of clinical studies investigating the utility of combining triphendiol and gemcitabine in patients with early-stage and late-stage pancreatic cancer.


Assuntos
Adenocarcinoma/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Isoflavonas/farmacologia , Neoplasias Pancreáticas/tratamento farmacológico , Adenocarcinoma/patologia , Animais , Apoptose/efeitos dos fármacos , Western Blotting , Caspases/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Avaliação Pré-Clínica de Medicamentos , Citometria de Fluxo , Humanos , Isoflavonas/administração & dosagem , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias Pancreáticas/patologia , Ensaios Antitumorais Modelo de Xenoenxerto , Gencitabina
12.
J Exp Clin Cancer Res ; 30: 44, 2011 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-21501525

RESUMO

BACKGROUND: Silibinin, a natural polyphenolic flavonoid, has been reported to induce cell death in various cancer cell types. However, the molecular mechanism is not clearly defined. Our previous study showed that silibinin induces glioma cell death and its effect was effectively prevented by calpain inhibitor. The present study was therefore undertaken to examine the role of calpain in the silibinin-induced glioma cell death. METHODS: U87MG cells were grown on well tissue culture plates and cell viability was measured by MTT assay. ROS generation and △ψm were estimated using the fluorescence dyes. PKC activation and Bax expression were measured by Western blot analysis. AIF nuclear translocation was determined by Western blot and immunocytochemistry. RESULTS: Silibinin induced activation of calpain, which was blocked by EGTA and the calpain inhibitor Z-Leu-Leu-CHO. Silibinin caused ROS generation and its effect was inhibited by calpain inhibitor, the general PKC inhibitor GF 109203X, the specific PKCδ inhibitor rottlerin, and catalase. Silibinin-induce cell death was blocked by calpain inhibitor and PKC inhibitors. Silibinin-induced PKCδ activation and disruption of △ψm were prevented by the calpain inhibitor. Silibinin induced AIF nuclear translocation and its effect was prevented by calpain inhibitor. Transfection of vector expressing microRNA of AIF prevented the silibinin-induced cell death. CONCLUSIONS: Silibinin induces apoptotic cell death through a calpain-dependent mechanism involving PKC, ROS, and AIF nuclear translocation in U87MG human glioma cells.


Assuntos
Antioxidantes/farmacologia , Fator de Indução de Apoptose/metabolismo , Apoptose/efeitos dos fármacos , Calpaína/metabolismo , Núcleo Celular/metabolismo , Silimarina/farmacologia , Calpaína/antagonistas & inibidores , Morte Celular/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Glioma/metabolismo , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Proteína Quinase C/metabolismo , Transporte Proteico/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Silibina , Proteína X Associada a bcl-2/metabolismo
13.
J Med Chem ; 52(7): 1853-63, 2009 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-19338355

RESUMO

Recent studies have demonstrated that glycogen synthase kinase 3beta (GSK-3beta) is overexpressed in human colon and pancreatic carcinomas, contributing to cancer cell proliferation and survival. Here, we report the design, synthesis, and biological evaluation of benzofuran-3-yl-(indol-3-yl)maleimides, potent GSK-3beta inhibitors. Some of these compounds show picomolar inhibitory activity toward GSK-3beta and an enhanced selectivity against cyclin-dependent kinase 2 (CDK-2). Selected GSK-3beta inhibitors were tested in the pancreatic cancer cell lines MiaPaCa-2, BXPC-3, and HupT3. We determined that some of these compounds, namely compounds 5, 6, 11, 20, and 26, demonstrate antiproliferative activity against some or all of the pancreatic cancer cells at low micromolar to nanomolar concentrations. We found that the treatment of pancreatic cancer cells with GSK-3beta inhibitors 5 and 26 resulted in suppression of GSK-3beta activity and a distinct decrease of the X-linked inhibitor of apoptosis (XIAP) expression, leading to significant apoptosis. The present data suggest a possible role for GSK-3beta inhibitors in cancer therapy, in addition to their more prominent applications in CNS disorders.


Assuntos
Antineoplásicos/síntese química , Benzofuranos/síntese química , Quinase 3 da Glicogênio Sintase/antagonistas & inibidores , Indóis/síntese química , Maleimidas/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Apoptose , Benzofuranos/química , Benzofuranos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Quinase 2 Dependente de Ciclina/antagonistas & inibidores , Ensaios de Seleção de Medicamentos Antitumorais , Quinase 3 da Glicogênio Sintase/química , Glicogênio Sintase Quinase 3 beta , Humanos , Indóis/química , Indóis/farmacologia , Maleimidas/química , Maleimidas/farmacologia , Modelos Moleculares , Neoplasias Pancreáticas , Relação Estrutura-Atividade , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/antagonistas & inibidores , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/biossíntese
14.
Dev Comp Immunol ; 33(1): 46-58, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-18761369

RESUMO

Hepcidin, an antimicrobial and iron-regulating peptide, is a key molecule of the innate immune system of bony fish. In this study, four isoforms of hepcidin genes were characterized from a marine Perciform fish, rockbream (Oplegnathus fasciatus), and the transcriptional modulations of these isoforms in response to different biological stimulations were also examined. All rockbream hepcidin isoform genes exhibited a tripartite structure and their promoter regions displayed typical binding motifs for the transcription factors including C/EBP, HNF, AP, NF-kbeta, GATA, USF and/or STAT. Hepcidin transcripts in juvenile or fingerling tissues were dramatically induced during experimental challenges with various bacterial species, iron overload and rockbream iridovirus infection. The transcription ofhepcidins was regulated in an isoform- and tissue-specific fashion. In addition, we identified for the first time that partially processed hepcidin transcripts were significantly elevated during bacterial infection and iron overload. Results from this study provide a good basis to better understand the isoform-specific role of hepcidin in the fish innate immune system.


Assuntos
Peptídeos Catiônicos Antimicrobianos/metabolismo , Perciformes/metabolismo , Fatores de Transcrição/metabolismo , Sequência de Aminoácidos , Animais , Peptídeos Catiônicos Antimicrobianos/genética , Infecções Bacterianas/metabolismo , Infecções Bacterianas/veterinária , Sequência de Bases , Doenças dos Peixes/metabolismo , Doenças dos Peixes/microbiologia , Hepcidinas , Iridovirus/fisiologia , Sobrecarga de Ferro/metabolismo , Sobrecarga de Ferro/veterinária , Dados de Sequência Molecular , Especificidade de Órgãos , Perciformes/genética , Perciformes/microbiologia , Regiões Promotoras Genéticas , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transcrição Gênica
15.
J Med Chem ; 49(13): 3832-49, 2006 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-16789740

RESUMO

Methionine aminopeptidase-2 (MetAP2) is a novel target for cancer therapy. As part of an effort to discover orally active reversible inhibitors of MetAP2, a series of anthranilic acid sulfonamides with micromolar affinities for human MetAP2 were identified using affinity selection by mass spectrometry (ASMS) screening. These micromolar hits were rapidly improved to nanomolar leads on the basis of insights from protein crystallography; however, the compounds displayed extensive binding to human serum albumin and had limited activity in cellular assays. Modifications based on structural information on the binding of lead compounds to both MetAP2 and domain III of albumin allowed the identification of compounds with significant improvements in both parameters, which showed good cellular activity in both proliferation and methionine processing assays.


Assuntos
Aminopeptidases/química , Antineoplásicos/síntese química , Metaloendopeptidases/química , Albumina Sérica/química , Sulfonamidas/síntese química , ortoaminobenzoatos/síntese química , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Técnicas In Vitro , Espectrometria de Massas , Metionina/metabolismo , Modelos Moleculares , Ligação Proteica , Conformação Proteica , Estrutura Terciária de Proteína , Ratos , Relação Estrutura-Atividade , Sulfonamidas/química , Sulfonamidas/farmacologia , ortoaminobenzoatos/química , ortoaminobenzoatos/farmacologia
16.
Bioorg Med Chem Lett ; 15(23): 5154-9, 2005 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-16198562

RESUMO

A novel triazole-containing chemical series was shown to inhibit tubulin polymerization and cause cell cycle arrest in A431 cancer cells with EC(50) values in the single digit nanomolar range. Binding experiments demonstrated that representative active compounds of this class compete with colchicine for its binding site on tubulin. The syntheses and structure-activity relationship studies for the triazole derivatives are described herein.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Triazóis/química , Triazóis/farmacologia , Moduladores de Tubulina/química , Moduladores de Tubulina/farmacologia , Antineoplásicos/síntese química , Humanos , Microtúbulos/efeitos dos fármacos , Estrutura Molecular , Relação Estrutura-Atividade , Triazóis/síntese química , Moduladores de Tubulina/síntese química , Células Tumorais Cultivadas
17.
J Fluoresc ; 15(1): 41-51, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15711876

RESUMO

We present a multicolor multiphoton fluorescence microscope with single-photon counting sensitivity. The system integrates a standard multiphoton fluorescence microscope, an optical grating spectrograph operating in the UV-Vis wavelength region, and a 16-anode photomultiplier tube (PMT). The major technical innovation is in the development of a multichannel photon counting card (mC-PhCC) for direct signal collection from multi-anode PMTs. The electronic design of the mC-PhCC employs a high-throughput, fully-parallel, single-photon counting scheme along with a high-speed electrical or fiber-optical link interface to the data acquisition computer. There is no electronic crosstalk among the detection channels of the mC-PhCC. The collected signal remains linear up to an incident photon rate of 10(8) counts per second. The high-speed data interface offers ample bandwidth for real-time readout: 2 MByte lambda-stacks composed of 16 spectral channels, 256 x 256 pixel image with 12-bit dynamic range can be transferred at 30 frames per second. The modular design of the mC-PhCC can be readily extended to accommodate PMTs of more anodes. Data acquisition from a 64-anode PMT has been verified. As a demonstration of system performance, spectrally resolved images of fluorescent latex spheres and ex-vivo human skin are reported. The multicolor multiphoton microscope is suitable for highly sensitive, real-time, spectrally-resolved three-dimensional imaging in biomedical applications.


Assuntos
Microscopia de Fluorescência por Excitação Multifotônica/métodos , Apresentação de Dados , Eletrônica , Desenho de Equipamento , Humanos , Técnicas In Vitro , Microscopia de Fluorescência por Excitação Multifotônica/instrumentação , Microscopia de Fluorescência por Excitação Multifotônica/estatística & dados numéricos , Microesferas , Fótons , Pele/anatomia & histologia , Pele/química
18.
Bioorg Med Chem Lett ; 14(4): 865-8, 2004 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-15012983

RESUMO

Substituted 3-amino-2-hydroxyamides and related hydroxyamides and acylhydrazines were identified as inhibitors of human methionine aminopeptidase-2 (MetAP2). Examination of substituents through parallel synthesis and iterative structure-based design allowed the identification of potent inhibitors with good selectivity against MetAP1. Diacylhydrazine 3t (A-357300) was identified as an analogue displaying inhibition of methionine processing and cellular proliferation in human microvascular endothelial cells (HMVEC).


Assuntos
Amidas/química , Amidas/farmacologia , Aminopeptidases/antagonistas & inibidores , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Metaloendopeptidases/antagonistas & inibidores , Sítios de Ligação/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Endotélio Vascular/citologia , Endotélio Vascular/efeitos dos fármacos , Humanos , Metionina/efeitos dos fármacos , Modelos Biológicos , Modelos Moleculares , Estrutura Molecular
19.
Bioorg Med Chem ; 10(5): 1367-72, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-11886800

RESUMO

3-D-Quantitative structure--activity relationships of N-(3-acyloxy-2-benzylpropyl)-N'-dihydroxytetrahydro-benzazepine and tetrahydroisoquinoline and N-(3-acyloxy-2-benzylpropyl)-N'-(4-hydroxy-3-methoxybenzyl) thiourea analogues as potent vanilloid receptor ligands were investigated using the CoMFA and the COMSIA methods. The best CoMFA model obtained in this study from 29 substituted thiourea analogues is a two-component model with the following statistics. R(2)((cv))=0.407 and RMSE((cv))=0.532 for the cross-validation, and R(2)=0.705 and RMSE=0.375 for the fitted. The best COMSIA model obtained from the same 29 compounds is a two-component model with the following statistics: R(2)((cv))=0.336 and RMSE((cv))=0.563 for the cross-validation, and R(2)=0.693 and RMSE=0.382 for the fitted.


Assuntos
Benzazepinas/metabolismo , Capsaicina/análogos & derivados , Isoquinolinas/metabolismo , Relação Quantitativa Estrutura-Atividade , Receptores de Droga/metabolismo , Tioureia/metabolismo , Analgésicos/química , Analgésicos/metabolismo , Animais , Benzazepinas/química , Capsaicina/química , Capsaicina/metabolismo , Células Cultivadas , Isoquinolinas/química , Ligantes , Modelos Moleculares , Ligação Proteica , Ratos , Receptores de Droga/antagonistas & inibidores , Tioureia/química
20.
Bioorg Med Chem Lett ; 12(3): 465-9, 2002 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-11814821

RESUMO

A series of indole containing oxazolines has been discovered as a result of structural modifications of the lead compound A-105972. The compounds exert their anticancer activity through inhibition of tubulin polymerization by binding at the colchicine site. A-289099 was identified as an orally active antimitotic agent active against various cancer cell lines including those that express the MDR phenotype. The anticancer activity, pharmacokinetics, and an efficient and enantioselective synthesis of A-289099 are described.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Indóis/síntese química , Indóis/farmacologia , Oxazóis/síntese química , Oxazóis/farmacologia , Tubulina (Proteína)/metabolismo , Animais , Antineoplásicos/farmacocinética , Disponibilidade Biológica , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Indóis/farmacocinética , Camundongos , Microtúbulos/efeitos dos fármacos , Microtúbulos/metabolismo , Modelos Moleculares , Oxazóis/farmacocinética , Polímeros/síntese química , Ratos , Estereoisomerismo , Células Tumorais Cultivadas
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