Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 11 de 11
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
J Am Chem Soc ; 145(44): 24035-24051, 2023 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-37874670

RESUMO

Establishing a technological platform for creating clinical compounds inhibiting intracellular protein-protein interactions (PPIs) can open the door to many valuable drugs. Although small molecules and antibodies are mainstream modalities, they are not suitable for a target protein that lacks a deep cavity for a small molecule to bind or a protein found in intracellular space out of an antibody's reach. One possible approach to access these targets is to utilize so-called middle-size cyclic peptides (defined here as those with a molecular weight of 1000-2000 g/mol). In this study, we validated a new methodology to create oral drugs beyond the rule of 5 for intracellular tough targets by elucidating structural features and physicochemical properties for drug-like cyclic peptides and developing library technologies to afford highly N-alkylated cyclic peptide hits. We discovered a KRAS inhibitory clinical compound (LUNA18) as the first example of our platform technology.


Assuntos
Peptídeos Cíclicos , Peptídeos Cíclicos/química
2.
Sci Rep ; 13(1): 16753, 2023 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-37798324

RESUMO

Intradialytic hypotension and arrhythmias are complications of hemodialysis. They are associated with decreased intravascular volume due to reduced ultrafiltration volume, cardiac function, and arterial tone. The vascular endothelial glycocalyx, which exists on the surface of healthy vascular endothelial cells and maintains vascular permeability, has been suggested to be impaired by hemodialysis. This single-center retrospective study evaluated the association between syndecan-1, an endothelial glycocalyx dysfunction marker, and complications of hemodialysis. We enrolled 92 patients who underwent outpatient hemodialysis at Gifu Seiryu Hospital from April to July 2022 (346 hemodialysis sessions). The median duration and time of hemodialysis were 40 months and 4.1 h, respectively. Median serum syndecan-1 levels were 67.7 ng/mL before and 98.3 ng/mL after hemodialysis. Hemodialysis complications were noted in 68 sessions, all of which were hypotension. No correlation between pre-hemodialysis syndecan-1 levels and the incidence of complications was observed. However, a positive correlation between the amount of change in syndecan-1 levels before and after hemodialysis and the incidence of hemodialysis complications was noted. Conversely, syndecan-1 levels did not correlate with brain or atrial natriuretic peptides, suggesting that impairment of the vascular endothelial glycocalyx may be a possible cause of intradialytic hypotension and may be useful in preventing intradialytic hypotension.


Assuntos
Hipotensão , Sindecana-1 , Humanos , Estudos Retrospectivos , Células Endoteliais , Diálise Renal/efeitos adversos , Hipotensão/etiologia
3.
Sci Rep ; 13(1): 9260, 2023 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-37286698

RESUMO

ATP6AP2, also known as (pro)renin receptor, has been shown to be expressed in several tissues including pancreatic ß cells. Whereas ATP6AP2 plays an important role in regulating insulin secretion in mouse pancreatic ß cells, the expression profiles and roles of ATP6AP2 in human pancreatic endocrine cells and neuroendocrine tumor cells remain unclear. Here in this study, we investigated the expression profiles of ATP6AP2 in pancreatic endocrine cells, and found that ATP6AP2 is robustly expressed in pancreatic insulinoma cells as well as in normal ß cells. Although ATP6AP2 was also expressed in low-grade neuroendocrine tumors, it was not or faintly detected in intermediate- and high-grade neuroendocrine tumors. Knockdown experiments of the Atp6ap2 gene in rat insulinoma-derived INS-1 cells demonstrated decreased cell viability accompanied by a significant increase in apoptotic cells. Taken together, these findings suggest that ATP6AP2 plays a role in maintaining cellular homeostasis in insulinoma cells, which could lead to possible therapeutic approaches for endocrine tumors.


Assuntos
Células Secretoras de Insulina , Insulinoma , Tumores Neuroendócrinos , Neoplasias Pancreáticas , ATPases Vacuolares Próton-Translocadoras , Camundongos , Ratos , Animais , Humanos , Células Secretoras de Insulina/metabolismo , Insulinoma/genética , Insulinoma/metabolismo , Tumores Neuroendócrinos/genética , Tumores Neuroendócrinos/metabolismo , Sobrevivência Celular/genética , ATPases Vacuolares Próton-Translocadoras/metabolismo , Receptores de Superfície Celular/metabolismo , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Receptor de Pró-Renina
4.
Adv Exp Med Biol ; 1232: 77-83, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31893397

RESUMO

Instantaneous orthostatic hypotension (INOH) is one of the main types of orthostatic dysregulation in children and adolescents. In patients with INOH arterial pressure drops considerably after active standing and is slow to recover. We investigated changes in cerebral oxygenation in the bilateral prefrontal cortex during an active standing test in juvenile INOH patients to evaluate changes in cerebral oxygen metabolism. We enrolled 82 INOH patients (mean age 13.8 ± 2.2 years, 52 mild and 30 severe patients) at Nihon University Itabashi Hospital from October 2013 to April 2018. We measured cerebral oxygenated hemoglobin, deoxygenated hemoglobin, and total hemoglobin levels in the bilateral prefrontal cortex using near-infrared spectroscopy during an active standing test. In severe INOH patients, cerebral oxygenation of the right prefrontal cortex remained constant when blood pressure dropped; however, de-oxy-Hb significantly increased. These findings confirm that there is asymmetrical autoregulation between the right and left prefrontal cortex.


Assuntos
Circulação Cerebrovascular , Hipotensão Ortostática , Adolescente , Circulação Cerebrovascular/fisiologia , Criança , Homeostase , Humanos , Hipotensão Ortostática/fisiopatologia , Oxiemoglobinas , Espectroscopia de Luz Próxima ao Infravermelho
5.
Cureus ; 11(9): e5608, 2019 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-31700721

RESUMO

So far, little attention has been paid to the increase in acute phase reactants (APRs) in patients with scurvy. We report that elevated levels of C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), and serum amyloid A were shown in a pediatric patient with scurvy despite the absence of inflammation. These peculiar findings are important to discriminate scurvy from other rheumatic diseases.

6.
Brain Dev ; 41(6): 559-562, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30772096

RESUMO

BACKGROUND: Confusional migraine is a rare type of migraine presenting as an acute confusional state. However, the mechanism of this confusional state remains unclear. SUBJECT AND METHODS: We examined an 11-year-old girl with confusional migraine, using electroencephalography, brain magnetic resonance imaging, cerebrovascular magnetic resonance angiography, and single-photon emission computed tomography to investigate cerebral blood flow changes. RESULTS: Our findings revealed vessel narrowing in the left middle and posterior cerebral artery territory, indicating vasospasm and suggesting that the confusion was caused by hypoperfusion. However, abnormal increased cerebral blood flow in the left middle and posterior cerebral artery territory was observed during the non-confusional state. CONCLUSION: The recorded cerebral blood flow changes are similar to those associated with migraine attacks, gradually changing from abnormally low to abnormally high during the confusional and post-confusional state.


Assuntos
Circulação Cerebrovascular/fisiologia , Transtornos de Enxaqueca/fisiopatologia , Criança , Confusão/fisiopatologia , Eletroencefalografia/métodos , Feminino , Humanos , Angiografia por Ressonância Magnética/métodos , Imageamento por Ressonância Magnética/métodos , Transtornos de Enxaqueca/sangue , Transtornos de Enxaqueca/complicações , Tomografia Computadorizada de Emissão de Fóton Único/métodos
7.
Naunyn Schmiedebergs Arch Pharmacol ; 387(4): 377-88, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24322587

RESUMO

To elucidate the roles played by the interstitial cells of Cajal in the myenteric layer (ICC-MY) in cholinergic neuromuscular transmission, we recorded mechanical and electrical activities in response to electrical field stimulation (EFS) of the ileal longitudinal muscle strips from WBB6F1-W/W(V) (W/W(V)) mutant mice, that lacked ICC-MY and compared with those in WBB6F1-+/+ (+/+) control mice. In +/+ muscle strips, EFS induced phasic contractions, which were abolished or strongly attenuated by atropine or tetrodotoxin. In W/W(V) preparations, EFS induced similar phasic contractions, but the cholinergic component was smaller than that in +/+ strips. This was despite of the fact that the contractions because of exogenous applications of carbachol and high K(+) solution in W/W(V) strips were comparable to or rather greater than those in the +/+ preparations. EFS induced atropine-sensitive excitatory junction potentials (EJPs) in the +/+ longitudinal smooth muscle cells but not in W/W(V) cells. In the presence of eserine, EFS induced atropine-sensitive EJPs in W/W(V) cells. These results suggest that ICC-MY mediate the cholinergic neuromuscular transmission in mouse ileal longitudinal smooth muscles. In addition, the other pathway in which ICC-MY are not involved can operate concomitantly.


Assuntos
Íleo/fisiologia , Células Intersticiais de Cajal/fisiologia , Músculo Liso/fisiologia , Plexo Mientérico/fisiologia , Adrenérgicos/farmacologia , Animais , Atropina/farmacologia , Colinérgicos/farmacologia , Estimulação Elétrica , Guanetidina/farmacologia , Íleo/inervação , Técnicas In Vitro , Masculino , Potenciais da Membrana , Camundongos , Camundongos Mutantes , Contração Muscular , Músculo Liso/inervação , NG-Nitroarginina Metil Éster/farmacologia , Junção Neuromuscular/fisiologia , Fisostigmina/farmacologia , Transmissão Sináptica
8.
Proc Natl Acad Sci U S A ; 108(42): 17533-7, 2011 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-21972415

RESUMO

A lipid extract of Perna canaliculus (New Zealand green-lipped mussel) has reportedly displayed anti-inflammatory effects in animal models and in human controlled studies. However, the anti-inflammatory lipid components have not been investigated in detail due to the instability of the lipid extract, which has made the identification of the distinct active components a formidable task. Considering the instability of the active component, we carefully fractionated a lipid extract of Perna canaliculus (Lyprinol) and detected furan fatty acids (F-acids). These naturally but rarely detected fatty acids show potent radical-scavenging ability and are essential constituents of plants and algae. Based on these data, it has been proposed that F-acids could be potential antioxidants, which may contribute to the protective properties of fish and fish oil diets against chronic inflammatory diseases. However, to date, in vivo data to support the hypothesis have not been obtained, presumably due to the limited availability of F-acids. To confirm the in vivo anti-inflammatory effect of F-acids in comparison with that of eicosapentaenoic acid (EPA), we developed a semisynthetic preparation and examined its anti-inflammatory activity in a rat model of adjuvant-induced arthritis. Indeed, the F-acid ethyl ester exhibited more potent anti-inflammatory activity than that of the EPA ethyl ester. We report on the in vivo activity of F-acids, confirming that the lipid extract of the green-lipped mussel includes an unstable fatty acid that is more effective than EPA.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Ácidos Graxos/farmacologia , Perna (Organismo)/química , Animais , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/isolamento & purificação , Artrite Experimental/tratamento farmacológico , Ácidos Graxos/química , Ácidos Graxos/isolamento & purificação , Feminino , Furanos/química , Furanos/isolamento & purificação , Furanos/farmacologia , Humanos , Lipídeos/química , Masculino , Estrutura Molecular , Oncorhynchus keta/metabolismo , Ratos , Ratos Endogâmicos Lew , Ratos Wistar , Testículo/química
9.
Toxicol In Vitro ; 24(6): 1720-6, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20510349

RESUMO

Many effects of sesamol, an antioxidative constituent of sesame oil, have been reported for human health benefits due to its antioxidative action. However, we recently isolated two cytotoxic products, trimer and tetramer of sesamol, from oxidation of sesamol by an assay-guided purification. In this study, we have revealed some cytotoxic characteristics of these products in rat thymocytes and human leukemia K562 cells. Incubation of cells with trimer or tetramer at 10-30 microM for 24h significantly increased cell lethality and population of rat thymocytes containing hypodiploid DNA, suggesting cell death with DNA fragmentation, while it was not the case for 30 microM sesamol. The cytotoxic action of tetramer was more potent than that of trimer in rat thymocytes when their concentrations were 10-30 microM. The incubation of cells with 10 microM tetramer for 24h increased the population of cells with exposed phosphatidylserine, the activity of caspases, and the nick of DNA. These results indicate tetramer-induced apoptosis. In K562 cells, the incubation with tetramer at 10 microM for 72 h significantly inhibited the growth without affecting the lethality. However, tetramer at 30 microM significantly increased cell lethality. It is likely that tetramer exerts more cytotoxic action on normal non-proliferative cells (rat thymocytes) rather than proliferative cancer cells (human leukemia K562 cells). It may be necessary to consider the condition for preservation of sesamol and the safety of products from in vivo oxidation of sesamol for human health.


Assuntos
Antioxidantes/toxicidade , Apoptose/efeitos dos fármacos , Benzodioxóis/toxicidade , Linfócitos/efeitos dos fármacos , Fenóis/toxicidade , Óleo de Gergelim/química , Animais , Antioxidantes/química , Benzodioxóis/química , Sobrevivência Celular/efeitos dos fármacos , Fracionamento Químico , Humanos , Células K562 , Linfócitos/patologia , Oxirredução , Fenóis/química , Ratos , Ratos Wistar , Timo/citologia
10.
Masui ; 58(7): 913-6, 2009 Jul.
Artigo em Japonês | MEDLINE | ID: mdl-19618836

RESUMO

The low femoral approach for catheterization of the central venous line is a difficult procedure because the surface landmark technique is not helpful. We report a case of patient who required the distal femoral cannulation. Re-catheter cannulation was planned for the patient after the major cardiovascular surgery. The right internal jugular vein showed the venous thrombus attributed to the previous catheter placement for the operation. The left internal, jugular vein had anatomical anomaly at the level of cricoid cartilage and the last approach for cannulation was not feasible. The right subclavian and right femoral regions were scarred with the surgical procedure. Finally, we performed the distal femoral cannulation using real time ultrasound guidance. When multiple difficulties for venous access are present, ultrasound-guided low approach of femoral vein might be one of the solutions.


Assuntos
Cateterismo Venoso Central/métodos , Veia Femoral , Idoso de 80 Anos ou mais , Dissecção Aórtica/cirurgia , Aneurisma da Aorta Torácica/cirurgia , Procedimentos Cirúrgicos Cardiovasculares , Veia Femoral/diagnóstico por imagem , Humanos , Masculino , Ultrassonografia de Intervenção/métodos
11.
Nanotechnology ; 17(22): 5539-43, 2006 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-21727321

RESUMO

Magnetic nanoparticle arrays have been fabricated by combining chemically synthesized Fe(3)O(4) nanoparticles with a diblock copolymer template substrate consisting of self-assembled polystyrene (PS) dots in a polymethylmethacrylate (PMMA) matrix. The influence of the volume fraction of the Fe(3)O(4) suspending solution and the withdrawal speed of the template on the formation of array structures was investigated. A small volume fraction of the nanoparticles and low withdrawal speed play an important role in the fabrication of the patterned arrays of nanoparticles via template assisted self-assembly. Below a withdrawal speed of 0.5 mm s(-1) and a nanoparticle volume fraction below 0.05 vol% (in particular, at extremely high dilutions of less than 0.01 vol%), the selective deposition of one to several nanoparticles on every single PS dot becomes possible.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...