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1.
Int J Mol Sci ; 25(4)2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38396699

RESUMO

Dengue virus (DENV) causes dengue fever and dengue hemorrhagic fever, and DENV infection kills 20,000 people annually worldwide. Therefore, the development of anti-DENV drugs is urgently needed. Sofosbuvir (SOF) is an effective drug for HCV-related diseases, and its triphosphorylated metabolite inhibits viral RNA synthesis by the RNA-dependent RNA polymerase (RdRp) of HCV. (2'R)-2'-Deoxy-2'-fluoro-2'-methyluridine (FMeU) is the dephosphorylated metabolite produced from SOF. The effects of SOF and FMeU on DENV1 replication were analyzed using two DENV1 replicon-based methods that we previously established. First, a replicon-harboring cell assay showed that DENV1 replicon replication in human hepatic Huh7 cells was decreased by SOF but not by FMeU. Second, a transient replicon assay showed that DENV1 replicon replication in Huh7 cells was decreased by SOF; however, in hamster kidney BHK-21 cells, it was not suppressed by SOF. Additionally, the replicon replication in Huh7 and BHK-21 cells was not affected by FMeU. Moreover, we assessed the effects of SOF on infectious DENV1 production. SOF suppressed infectious DENV1 production in Huh7 cells but not in monkey kidney Vero cells. To examine the substrate recognition of the HCV and DENV1 RdRps, the complex conformation of SOF-containing DENV1 RdRp or HCV RdRp was predicted using AlphaFold 2. These results indicate that SOF may be used as a treatment for DENV1 infection.


Assuntos
Hepatite C , Sofosbuvir , Animais , Cricetinae , Chlorocebus aethiops , Humanos , Sofosbuvir/farmacologia , Antivirais/farmacologia , Células Vero , RNA Polimerase Dependente de RNA , Replicação Viral , Hepacivirus/genética
2.
J Am Chem Soc ; 143(23): 8866-8877, 2021 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-34096298

RESUMO

Mechanically responsive crystals have been increasingly explored, mainly based on photoisomerization. However, photoisomerization has some disadvantages for crystal actuation, such as a slow actuation speed, no actuation of thick crystals, and a narrow wavelength range. Here we report photothermally driven fast-bending actuation and simulation of a salicylideneaniline derivative crystal with an o-amino substituent in enol form. Under ultraviolet (UV) light irradiation, these thin (<20 µm) crystals bent but the thick (>40 µm) crystals did not due to photoisomerization; in contrast, thick crystals bent very quickly (in several milliseconds) due to the photothermal effect, even by visible light. Finally, 500 Hz high-frequency bending was achieved by pulsed UV laser irradiation. The generated photothermal energy was estimated based on the photodynamics using femtosecond transient absorption. Photothermal bending is caused by a nonsteady temperature gradient in the thickness direction due to the heat conduction of photothermal energy generated near the crystal surface. The temperature gradient was calculated based on the one-dimensional nonsteady heat conduction equation to simulate photothermally driven crystal bending successfully. Most crystals that absorb light have their own photothermal effects. It is expected that the creation and design of actuation of almost all crystals will be possible via the photothermal effect, which cannot be realized by photoisomerization, and the potential and versatility of crystals as actuation materials will expand in the near future.

3.
Biologicals ; 44(4): 206-211, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27233579

RESUMO

Neuropathic pain caused by nerve damage in the central and/or peripheral nervous systems is a refractory disorder and the management of such chronic pain has become a major issue. Neurotropin is a drug widely used in Japan and China to treat chronic pain. Although Neurotropin has been demonstrated to suppress chronic pain through the descending pain inhibitory system, the mechanism of analgesic action in the peripheral nervous system remains to be elucidated. In this study, we investigated the local effects of Neurotropin on peripheral nerve damage in a chronic constriction injury (CCI) model. Neurotropin reduced mRNA expressions of IL-1ß, IL-6, and TNF-α in the sciatic nerve 1 day after the injury. Activation of Erk was also inhibited locally in the Neurotropin treatment group. Since Erk activation results in demyelination along with dedifferentiation of Schwann cells, we investigated the expression level of myelin basic protein. Five days after the injury, Neurotropin attenuated the downregulation of myelin basic protein in the sciatic nerve in the CCI model. Local effects of Neurotropin around the injury site may result in discovery of new treatments for not only neuropathic pain but also demyelinating diseases and peripheral nervous system injury.


Assuntos
Citocinas/genética , Doenças Desmielinizantes/prevenção & controle , Polissacarídeos/farmacologia , Nervo Isquiático/lesões , Analgésicos/farmacologia , Animais , Western Blotting , Doença Crônica , Constrição , Citocinas/metabolismo , Doenças Desmielinizantes/etiologia , Modelos Animais de Doenças , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Expressão Gênica/efeitos dos fármacos , Mediadores da Inflamação/metabolismo , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Interleucina-6/genética , Interleucina-6/metabolismo , Camundongos Endogâmicos C57BL , Microscopia de Fluorescência , Neuralgia/prevenção & controle , Traumatismos dos Nervos Periféricos/complicações , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
5.
Nat Commun ; 14(1): 1354, 2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-36907883

RESUMO

The flourishing field of soft robotics requires versatile actuation methodology. Natural vibration is a physical phenomenon that can occur in any material. Here, we report high-speed bending of anisole crystals by natural vibration induced by the photothermal effect. Rod-shaped crystal cantilevers undergo small, fast repetitive bending (~0.2°) due to natural vibration accompanied by large photothermal bending (~1°) under ultraviolet light irradiation. The natural vibration is greatly amplified by resonance upon pulsed light irradiation at the natural frequency to realise high frequency (~700 Hz), large bending (~4°), and high energy conversion efficiency from light to mechanical energy. The natural vibration is induced by the thermal load generated by the temperature gradient in the crystal due to the photothermal effect. The bending behaviour is successfully simulated using finite element analysis. Any light-absorbing crystal can be actuated by photothermally induced natural vibration. This finding of versatile crystal actuation can lead to the development of soft robots with high-speed and high-efficient actuation capabilities.

6.
Mater Horiz ; 10(11): 4922-4929, 2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37606516

RESUMO

We impregnated the sugar alcohols (SAs) erythritol and mannitol (Man) in >0.1 mm single crystals of a covalent organic framework, COF-300, to propose new solid-state heat storing materials. The fusion-freezing cycles of the Man-COF composite occur in a narrow range of 130-155 °C without large or random supercooling, which has been a crucial problem of SAs, indicating the significance of this materials concept. The Man-COF composite displayed two endothermic and two exothermic features in the heating/cooling cycles. We measured the heat transmission properties in detail, based on which we discuss and suggest a postulate on the phase change behaviour of Man in the pores of the COF.

7.
Anal Sci ; 38(8): 1019-1024, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35668347

RESUMO

It has been found that a fluorophore-linked adamantylideneadamantane 1,2-dioxetane derivative showed an isomeric difference in the reactivities of crystalline-state chemiluminescence (CL) under isothermal heating conditions, while there are still unsolved problems on the conditions for intracrystalline reactions. To confirm the suitable heating conditions for initiating crystalline-state CL reactions of the isomers, the CL reactions in their crystal samples heated at elevated temperature were investigated with monitoring of CL light emission and thermogravimetry-differential thermal analysis (TG-DTA) measurements together with a simultaneous measurement method of thermal diffusivity and light emission, to provide the information on suitable temperature range for the crystalline-state CL reactions and on the reactivities depending on open and closed conditions of the crystal samples. The newly developed simultaneous measurement method provides a methodology for a single crystal to analyze the relationship between a change of the thermophysical property of inside of the crystal and the progress of a crystalline-state CL reaction.


Assuntos
Calefação , Luminescência , Corantes Fluorescentes , Compostos Heterocíclicos com 1 Anel , Temperatura , Termogravimetria
8.
Case Rep Oncol ; 15(2): 599-605, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35949910

RESUMO

Myoepithelial neoplasms (MNs) of the lung are extremely rare tumors. Approximately 40 cases of pulmonary MNs have been reported to date. Herein, we report extremely rare cases of different types of pulmonary MN, including cytological features. Case 1 is an 18-year-old female, and case 2 is a 73-year-old female patient. They presented to our hospital with nodules of the lung. Histological examination revealed tumor cells with round to oval nuclei and acidophilic cytoplasm that formed nests or fascicles with mild hyalinized stroma in case 1 and tumors containing the bi-phasic components of a nest-like and fascicle pattern with pleomorphism in case 2. Immunohistochemically, these tumors were positive for cytokeratin (CK) AE1/AE3, CK5/6, vimentin, calponin, and EMA, and focal positive for S-100a protein and alpha smooth muscle actin. The pathological diagnoses in cases 1 and 2 were myoepithelioma and myoepithelial carcinoma, respectively. In conclusion, we encountered two cases of extremely rare MNs that occurred in the lung. This disease can be diagnosed by collecting appropriate cytological and histological findings and should be listed as a differential diagnosis.

9.
Micromachines (Basel) ; 11(8)2020 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-32751390

RESUMO

The thermal properties of novel nanomaterials play a significant role in determining the performance of the material in technological applications. Herein, direct measurement of the temperature diffusivity of nanocellulose-doped starch-polyurethane nanocomposite films was carried out by the micro-contact method. Polymer films containing up to 2 wt%. of nanocellulose were synthesised by a simple chemical process and are biodegradable. Films of a high optical transmittance T≈80% (for a 200 µm thick film), which were up to 44% crystalline, were characterised. Two different modalities of temperature diffusivity based on (1) a resistance change and (2) micro-thermocouple detected voltage modulation caused by the heat wave, were used for the polymer films with cross sections of ∼100 µm thickness. Twice different in-plane α‖ and out-of-plane α⟂ temperature diffusivities were directly determined with high fidelity: α‖=2.12×10-7 m2/s and α⟂=1.13×10-7 m2/s. This work provides an example of a direct contact measurement of thermal properties of nanocellulose composite biodegradable polymer films. The thermal diffusivity, which is usually high in strongly interconnected networks and crystals, was investigated for the first time in this polymer nanocomposite.

10.
Proteomics ; 8(8): 1706-19, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18340631

RESUMO

To clarify roles of an endogenous pain modulatory system of the central nervous system (CNS) in hyperalgesia, we tried to identify qualitative and quantitative protein changes by a proteomic analysis using an animal model of hyperalgesia. Specifically, we first induced functional hyperalgesia on male Wistar rats by repeated cold stress (specific alternation of rhythm in temperature, SART). We then compared proteomes of multiple regions of CNS and the dorsal root ganglion between the hyperalgetic rats and non-treated ones by 2-D PAGE in the pI range of 4.0-7.0. We found that SART changed the proteomes prominently in the mesencephalon and cerebellum. We thus analyzed the two brain regions in more detail using gels with narrower pI ranges. As a result, 29 and 23 protein spots were significantly changed in the mesencephalon and the cerebellum, respectively. We successfully identified 12 protein spots by a MALDI-TOF/TOF MS and subsequent protein database searching. They included unc-18 protein homolog 67K, collapsin response mediator protein (CRMP)-2 and CRMP-4, which were reported to be involved in neurotransmitter release or axon elongation. Interestingly, mRNA expression levels of these three proteins were not changed significantly by the induction of hyperalgesia. Instead, we found that the detected changes in the protein spots are caused by the post-translational modification (PTM) of proteolysis or phosphorylation. Taken together, development of the hyperalgesia would be linked to PTM of these three CNS proteins. PTM regulation may be one of the useful ways to treat hyperalgesia.


Assuntos
Encéfalo/metabolismo , Hiperalgesia/metabolismo , Proteínas Munc18/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Plasticidade Neuronal/fisiologia , Processamento de Proteína Pós-Traducional , Proteoma/análise , Animais , Western Blotting , Temperatura Baixa/efeitos adversos , Primers do DNA , Eletroforese em Gel Bidimensional , Eletroforese em Gel de Poliacrilamida , Hiperalgesia/etiologia , Peptídeos e Proteínas de Sinalização Intercelular , Masculino , Mecanorreceptores/metabolismo , Nociceptores/metabolismo , Fosforilação , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
11.
Chem Commun (Camb) ; 53(29): 4073-4076, 2017 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-28345082

RESUMO

A synthetic route to the septahydroxylated ABC-ring system of dihydro-ß-agarofurans was established. The B-ring was formed by a base-promoted diastereoselective Diels-Alder reaction between 3-hydroxy-2-pyrone and a d-glyceraldehyde-derived dienophile, while the C-ring was cyclized by PhSeCl-mediated etherification. The remaining A-ring was constructed via a 6-exo-dig radical reaction. Selective transformations gave rise to the ABC-ring system 1 with nine contiguous stereocenters. The thus obtained 1 corresponded to the enantiomer of the densely oxygenated core structure of dihydro-ß-agarofurans.

12.
Life Sci ; 171: 39-44, 2017 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-28039003

RESUMO

AIMS: Neurotropin® (NTP), an analgesic for chronic pain, has antihyperalgesic effects in specific alternation of rhythm in temperature (SART)-stressed rats. Previous studies have shown that SART stress induces hyperalgesia, as well as post-translational modification of proteins (including substrates for calpain, a calcium-dependent cysteine protease) in the mesencephalon of rats. To better understand the mechanism of action of NTP, we investigated whether SART stress activates calpain in the mesencephalon of rats and whether NTP inhibits this activation. MAIN METHODS: Wistar rats were exposed to SART stress for 5days. NTP (200NU/kg/day) was administered intraperitoneally every day from the onset of SART stress. The mechanical pain threshold was measured using the Randall-Selitto test on the 6th day. Thereafter, the rat mesencephalon was immediately collected and calpain activity was examined using western blot analysis with a calpain cleavage site-specific antibody. KEY FINDINGS: SART stress induced hyperalgesia and increased the calpain activity in the mesencephalon of rats. In contrast, NTP treatment attenuated the hyperalgesia and prevented the increase in calpain activity in the mesencephalon of SART-stressed rats. Interestingly, a negative correlation was identified between calpain activity and mechanical pain threshold in SART-stressed rats treated with or without NTP. Furthermore, NTP inhibited calpain activity on mammalian uncoordinated-18 in rat mesencephalon homogenate and Ac-LLY-AFC as substrates in an in vitro cell-free system. SIGNIFICANCE: Our data demonstrate that NTP treatment prevents SART stress-induced calpain activation in the mesencephalon of rats and suggests that NTP-mediated antihyperalgesia is associated with an inhibition of calpain activity in the mesencephalon.


Assuntos
Analgésicos/farmacologia , Temperatura Corporal , Calpaína/antagonistas & inibidores , Mesencéfalo/efeitos dos fármacos , Polissacarídeos/farmacologia , Regulação para Cima/fisiologia , Animais , Calpaína/metabolismo , Hiperalgesia/prevenção & controle , Masculino , Mesencéfalo/metabolismo , Mesencéfalo/fisiologia , Ratos , Ratos Wistar , Estresse Fisiológico , Especificidade por Substrato
13.
J Diabetes Complications ; 19(6): 328-34, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16260349

RESUMO

To clarify whether transition metals are involved in carbonyl stress in diabetic tissues, we observed the effects of a metal chelating agent, trientine (TE) hydrochloride on the levels of methylglyoxal (MG), 3-deoxyglucosone (3-DG), advanced glycation end products, 8-hydroxy-2'-deoxyguanosine (8-OHdG), and polyol pathway metabolites along with semicarbazide-sensitive amine oxidase (SSAO) enzyme activity in lenses from streptozotocin-induced diabetic rats. Lens MG and 3-DG levels were significantly higher in diabetic rats than nondiabetic controls, and TE significantly restored the increase of these compounds. Lens argpyrimidine was also increased in diabetic rats as compared with controls and was significantly reduced by TE. Lens SSAO activity and 8-OHdG were also significantly elevated in diabetic rats, and TE suppressed both of them, whereas TE showed no effect on the polyol pathway metabolites. The results indicate that transition metals play a significant role in the formation of MG and 3-DG via oxidative stress and SSAO activity.


Assuntos
Quelantes/uso terapêutico , Cobre/metabolismo , Diabetes Mellitus Experimental/tratamento farmacológico , Cristalino/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Trientina/uso terapêutico , 8-Hidroxi-2'-Desoxiguanosina , Amina Oxidase (contendo Cobre)/efeitos dos fármacos , Amina Oxidase (contendo Cobre)/metabolismo , Animais , Desoxiglucose/análogos & derivados , Desoxiglucose/metabolismo , Desoxiguanosina/análogos & derivados , Desoxiguanosina/metabolismo , Diabetes Mellitus Experimental/metabolismo , Produtos Finais de Glicação Avançada/metabolismo , Cristalino/metabolismo , Masculino , Ornitina/análogos & derivados , Ornitina/metabolismo , Polímeros/metabolismo , Pirimidinas/metabolismo , Aldeído Pirúvico/metabolismo , Ratos , Ratos Sprague-Dawley
14.
Org Lett ; 15(17): 4488-91, 2013 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-23937168

RESUMO

The multiply oxygenated ABC-ring system of the dihydro-ß-agarofurans was synthesized by employing two highly stereoselective reactions. The quinidine-catalyzed Diels-Alder reaction between a chiral dienophile and 3-hydroxy-4-methyl-2-pyrone simultaneously installed the C2-stereogenic center and two contiguous tetrasubstituted carbon centers (C5 and C10) of the A-ring. After 12 additional transformations, the aldol reaction of the resulting spiral AC-ring cyclized the B-ring with stereoselective introduction of the C7- and C8-centers.


Assuntos
Pironas/química , Sesquiterpenos/síntese química , Celastraceae/química , Ciclização , Reação de Cicloadição , Estrutura Molecular , Quinidina/química , Sesquiterpenos/química , Estereoisomerismo
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