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1.
Cardiovasc Intervent Radiol ; 46(10): 1375-1382, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37524895

RESUMO

PURPOSE: To assess the efficacy and safety of intra-arterial injection of imipenem/cilastatin sodium (IPM/CS) via a needle placed into the radial artery or ulnar artery (RA/UA) for distal interphalangeal and proximal interphalangeal joint osteoarthritis (DIP/PIP-OA). MATERIALS AND METHODS: This is a retrospective single-arm cohort study. Ninety-two patients [92% women, mean (SD) age 55(8.3) years] with a primary DIP/PIP-OA meet the American College of Rheumatology criteria for hand osteoarthritis with pain ≥ 4 on the 0-10 numeric rating scale (NRS) were enrolled. All procedures were performed by injecting IPM/CS through a 24-gauge needle percutaneously inserted into the RA/UA. Two procedures were planned; the second procedure was scheduled 1-2 months after the first. NRS, Quick Disabilities of the Arm, Shoulder, and Hand (QuickDASH) score, Patient Global Impression of Change (PGIC) scale, and procedure-related adverse events were evaluated. RESULTS: Technical success, defined as injection of IPM/CS into the RA/UA, was achieved in all patients. Clinical success, defined as a reduction of 2 points or more in the NRS at 12 months, was 77% (95% confidence interval 68-85%). The NRS improved from the baseline to 3, 6, and 12 months (7.8 ± 1.6 vs. 3.8 ± 2.6, 3.9 ± 2.7, and 4.0 ± 2.8, respectively, all p < 0.001). The QuickDASH score improved from the baseline to 12 months (27 ± 15 vs. 19 ± 17, p < 0.001) respectively. No major adverse events were observed. CONCLUSIONS: Intra-arterial injection of IPM/CS is a feasible treatment option for DIP/PIP-OA.


Assuntos
Osteoartrite , Artéria Ulnar , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Estudos Retrospectivos , Estudos de Coortes , Injeções Intra-Arteriais , Radiografia , Osteoartrite/diagnóstico por imagem , Osteoartrite/terapia
2.
Bioorg Med Chem ; 68: 116857, 2022 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-35661849

RESUMO

Africane-type sesquiterpenoids are a unique tricyclic carbon architecture sesquiterpenoid isolated as natural products. Δ9(15) -africanene has been reported to exhibit anti-inflammatory activity for carrageenan-induced rat foot edema. In this study, we reported structure-activity relationship study of africane-type sesquiterpenoids and found that some africane-type sesquiterpenoid analogs and their synthetic intermediate showed potent anti-inflammatory activity. To identify the mode of action of africane-type sesquiterpenoids and their synthetic intermediate, we evaluated the anti-inflammatory activity using lipopolysaccharide (LPS)-stimulated mouse macrophage RAW264.7 cells. Treatment with the africane-type compounds and their synthetic intermediate suppressed LPS-induced expressions of Cox-2 protein and mRNAs of the inflammatory cytokines IL-1ß and IL-6 at the concentrations that did not affect cell viability. Interestingly, although these africane-type compounds and their synthetic intermediate suppressed the pro-inflammatory cytokines' expressions, the compounds did not modulate NF-κB activation. These results suggest that the africane-type compounds and their synthetic intermediate are anti-inflammatory compounds that suppress the expression of LPS-induced inflammatory mediators independently of NF-κB activation.


Assuntos
Lipopolissacarídeos , Sesquiterpenos , Animais , Anti-Inflamatórios/farmacologia , Citocinas/metabolismo , Lipopolissacarídeos/farmacologia , Camundongos , NF-kappa B/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Ratos , Sesquiterpenos/farmacologia
3.
Chem Biodivers ; 19(3): e202100890, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35018704

RESUMO

Practical total syntheses of africane-type sesquiterpenoids were realized by reexamination of a divergent strategy employing optimized three-component coupling followed by ring-closing metathesis and substrate-controlled cyclopropanation. This sequential eight-step conversion provided Δ9(15) -africanene, a common bicyclo[5.3.0]decane intermediate for the syntheses of africane derivatives, in more than twice the yield as in the previous approach. The scalability and robustness of this improved synthetic route were confirmed by gram-scale preparation of Δ9(15) -africanene. In vitro cell-based assays of the synthesized africane-type sesquiterpenoids disclosed that ester-incorporating derivatives showed cytotoxic activity against HeLa cells. The effect of relative and absolute configuration of africane-9,15-diol monoacetates on the cytotoxicity against HeLa cells was also investigated.


Assuntos
Sesquiterpenos , Células HeLa , Humanos , Sesquiterpenos/farmacologia , Estereoisomerismo
4.
Opt Lett ; 46(8): 1904-1907, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33857100

RESUMO

Slow light generated through silicon (Si) photonic crystal waveguides (PCWs) is useful for improving the performance of Si photonic devices. However, the accumulation of coupling loss between a PCW and Si optical wiring waveguides is a problem when slow-light devices are connected in a series in a photonic integrated circuit. Previously, we reported a tapered transition structure between these waveguides and observed a coupling loss of 0.46 dB per transition. This Letter employed particle swarm optimization to engineer the arrangement of photonic crystal holes to reduce loss and succeeded in demonstrating theoretical loss value of 0.12 dB on average in the wavelength range of 1540-1560 nm and an experimental one of 0.21 dB. Crucially, this structure enhances the versatility of slow light.

5.
Biosci Biotechnol Biochem ; 84(4): 797-799, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31790630

RESUMO

Insect gall structures have many characteristic forms and colors, which are distinguishable from host plants. In this study, we identified an anthocyanin from red color insect galls and revealed that the anthocyanin biosynthesis of plants was induced by the gall extracts. The galling insects presumably regulate the anthocyanin biosynthesis of host plants to protect their larvae from environmental stresses.


Assuntos
Antocianinas/química , Ceratopogonidae/fisiologia , Fagus/parasitologia , Galactosídeos/química , Interações Hospedeiro-Parasita , Animais , Antocianinas/biossíntese , Ceratopogonidae/crescimento & desenvolvimento , Fagus/metabolismo , Larva/fisiologia
6.
Org Lett ; 21(10): 3554-3557, 2019 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-31058517

RESUMO

The first total synthesis of pactalactam was accomplished using substrate-controlled stereoselective aziridination and regioselective aziridine ring-opening to construct three continuous amino groups on an octasubstituted cyclopentane core. The cyclopentane framework was obtained by ring-closing metathesis and aldol coupling using a l-threonine-derived oxazoline compound. Cyclic urea formation, m-acetylphenyl group introduction by Chan-Lam coupling, and primary alcohol-selective acylation yielded the reported pactalactam structure. The presence of pactalactam in the fermentation broth of pactamycin-producing bacteria was also confirmed.


Assuntos
Álcoois/química , Aziridinas/química , Ciclopentanos/química , Imidazolidinas/síntese química , Pactamicina/síntese química , Acilação , Imidazolidinas/química , Estrutura Molecular , Pactamicina/química
7.
J Org Chem ; 83(13): 7019-7032, 2018 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-29419300

RESUMO

The convergent total synthesis of the natural product paecilomycin B and its 6'-epimer was investigated. The aryl- C-glycoside skeleton was constructed by an intramolecular Barbier-type reaction using 2,4,6-triisopropylphenyllithium and subsequent deoxygenation of the resulting anomeric hydroxy group. Starting from aryl iodide 24, the addition reaction afforded the thermodynamically stable C-ß macrocyclic adduct 41a in 29% yield and the C-α adduct 41b in 1% yield. Meanwhile, aryl iodide 43 (6'-epimer of 24) gave only the C-α adduct 44 in 76% yield. The stereoselectivities of these nucleophilic addition reactions are also discussed.

8.
Intern Med ; 55(22): 3247-3256, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27853065

RESUMO

Objective The effects of febuxostat therapy on hyperuricemia in patients with and without type 2 diabetes were compared in this retrospective observational study after pair-matching using the propensity scores. Methods In total, 160 patients with hyperuricemia were studied as the treated set, and the 155 subjects in whom the administration of febuxostat was not discontinued during the observation period were investigated in the full analysis. The study subjects were divided into two groups based on the style of initiation of febuxostat: initial and switching therapy from allopurinol administration. Results The reduction in the serum uric acid (sUA) levels at six months after the initiation of febuxostat administration did not significantly differ between the patients with and without diabetes in both the initial (206±114 and 226±113 µmol/L in patients with and without diabetes, respectively) and switching (154±91 and 129±90 µmol/L in patients with and without diabetes, respectively) therapy groups. The eGFR values were significantly increased compared to the baseline levels only in the patients without diabetes. The changes in the eGFR values were significantly associated with the presence of diabetes and sUA at baseline in a multivariate analysis. The frequency of adverse events was not significantly different between the patients with and without diabetes. Conclusion Although febuxostat exerted a similar sUA-lowering effect against hyperuricemia in patients with type 2 diabetes compared to those without, the renoprotective effect was attenuated in those with diabetes compared to nondiabetic subjects.


Assuntos
Diabetes Mellitus Tipo 2/complicações , Inibidores Enzimáticos/uso terapêutico , Febuxostat/uso terapêutico , Hiperuricemia/tratamento farmacológico , Xantina Desidrogenase/antagonistas & inibidores , Adulto , Alopurinol/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Feminino , Humanos , Hiperuricemia/etiologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Ácido Úrico/sangue
9.
Chem Pharm Bull (Tokyo) ; 64(6): 602-8, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27250795

RESUMO

A toxic mushroom, Russula subnigricans, causes fatal poisoning by mistaken ingestion. In spite of the potent bioactivity, the responsible toxin had not been identified for about 50 years since its first documentation. Recently, we isolated an unstable toxin and determined the structure. The slow elucidation was partly due to the instability of the toxin and also due to misidentification of R. subnigricans for similar mushrooms. To discriminate genuine Russula subnigricans from similar unidentified Russula species, we searched for a unique chemical marker contained in the mushroom. Cyclopropylacetyl-(R)-carnitine specific to R. subnigricans was identified as a novel compound whose (1)H-NMR signals appearing in the upfield region were easily recognizable among the complicated signals of the crude extract.


Assuntos
Agaricales/química , Carnitina/análogos & derivados , Carnitina/análise , Estrutura Molecular , Espectroscopia de Prótons por Ressonância Magnética , Estereoisomerismo
10.
Org Lett ; 17(12): 2890-3, 2015 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-25937148

RESUMO

Starting from the glucose-derived δ-lactone and the functionalized aryl bromide, the first total synthesis of naturally occurring paecilomycin B was achieved via functionalized aryl-ß-C-glycoside synthesis using 2,4,6-triisopropylphenyllithium under Barbier-type reaction conditions and ring-closing metathesis as the key steps.


Assuntos
Glucose/química , Hidrocarbonetos Bromados/química , Lactonas/química , Compostos Macrocíclicos/síntese química , Lactonas/síntese química , Compostos Macrocíclicos/química , Estrutura Molecular
11.
J Org Chem ; 79(21): 9922-47, 2014 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-25136928

RESUMO

Ansa compounds are gifts from microbes with intriguing molecular structures and highly potent bioactivities. One of the ansa compounds, kendomycin, has an oxa-metacyclophane skeleton with a quinone methide core and a fully substituted tetrahydropyran ring. Beyond a common synthetic strategy for construction of the ansa skeleton (i.e., elongation of an alkyl chain from an aromatic core followed by macrocyclization), we challenged a new method for construction of the ansa skeleton via simultaneous macrocyclization and benzannulation (using an intramolecular Dötz benzannulation). Understanding the reactivity of various Fischer-type ω-alkynyloxy chromium carbene complexes with kendomycin analogue syntheses led to achievement of the total synthesis of kendomycin. Investigations of structure-activity relationships revealed the need for an ansa skeleton for antimicrobial activity. Therefore, we envisage that this intramolecular Dötz benzannulation will enable divergent syntheses of ansa compounds which have important bioactive potential.


Assuntos
Compostos Macrocíclicos/síntese química , Quinonas/química , Rifabutina/análogos & derivados , Complexos de Coordenação/química , Compostos Macrocíclicos/química , Metano/análogos & derivados , Metano/química , Rifabutina/síntese química , Rifabutina/química , Relação Estrutura-Atividade
12.
Org Lett ; 16(2): 358-61, 2014 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-24364475

RESUMO

Isopropyl carbamates derived from benzylamines provide isoindolinones by treatment with phosphorus pentoxide at room temperature. Utility of this Bischler-Napieralski-type cyclization and a new mechanism involving a carbamoyl cation for rationalization of this smooth conversion are discussed.


Assuntos
Benzilaminas/química , Carbamatos/química , Indóis/síntese química , 2-Propanol/química , Ciclização , Ésteres , Indóis/química , Estrutura Molecular , Compostos de Fósforo/química , Temperatura
14.
Bioorg Med Chem ; 20(22): 6583-8, 2012 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-23063519

RESUMO

A toxic protein, dubbed molybdophyllysin, was isolated from the tropical toadstool Chlorophyllum molybdites by following its lethal effect in mice. Analysis of the protein using SDS-PAGE revealed a single 23-kDa band. Sequence analysis of molybdophyllysin tryptic fragments showed that this protein is highly homologous to metalloendopeptidases (MEPs) obtained from edible mushrooms, such as Grifola frondosa, Pleurotus ostreatus, and Armillaria mellea. These proteins include a HEXXH+D zinc-binding motif known as aspzincin. Accordingly, molybdophyllysin is a member of the deuterolysin family of zinc proteases. Molybdophyllysin retained its proteolytic activity at temperatures up to 60°C with an optimum pH of 7.0. The activity was inhibited by both 1,10-phenanthroline and N-bromosuccinimide, but molybdophyllysin exhibited strong resistance to SDS.


Assuntos
Agaricales/enzimologia , Metaloendopeptidases/metabolismo , Sequência de Aminoácidos , Animais , Bromosuccinimida/química , Concentração de Íons de Hidrogênio , Metaloendopeptidases/antagonistas & inibidores , Metaloendopeptidases/química , Metaloendopeptidases/isolamento & purificação , Camundongos , Dados de Sequência Molecular , Fenantrolinas/química , Homologia de Sequência de Aminoácidos , Temperatura , Zinco/química , Zinco/metabolismo
15.
J Org Chem ; 76(15): 6258-63, 2011 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-21702442

RESUMO

A racemic total synthesis of the sesquiterpenoid unit of the hybrid marine natural product polymaxenolide has been achieved based on a three-component assembly followed by ring-closing metathesis as the key steps. However, the spectral data of our product synthesized from Δ(9(15))-africanene by epoxidation were not identical with those of the natural product named epoxyafricanane. The structure confirmation of the synthetic nominal epoxyafricanane is described.


Assuntos
Toxinas Marinhas/química , Sesquiterpenos/síntese química , Terpenos/química , Terpenos/síntese química , Produtos Biológicos , Ciclização , Estrutura Molecular , Sesquiterpenos/química , Estereoisomerismo
16.
J Org Chem ; 75(16): 5573-9, 2010 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-20704431

RESUMO

The lactonamycin model aglycon 4 was synthesized from the trihalogenated benzene derivative 10. Ethynyltetraol 6 was prepared from 10 via carbon elongations, oxidative demethylation, a cycloaddition reaction with the diene derived from homophthalic anhydride, and dihydroxylation. Final E- and F-ring constructions from 6 were realized via a palladium-catalyzed cyclization-methoxycarbonylation, a stereoselective methanol addition, and lactonization, leading to the production of 4.


Assuntos
Ciclização , Indóis/síntese química , Indóis/química , Estrutura Molecular , Naftoquinonas/síntese química , Naftoquinonas/química , Estereoisomerismo
17.
Org Lett ; 12(8): 1700-3, 2010 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-20225835

RESUMO

One-step formation of the ansa-skeleton realized the synthesis of kendomycin, an ansa-type quinone methide. The Fischer carbene complex derived from the ansa-chain portion was subjected to the intramolecular Dotz benzannulation to afford the desired oxametacyclophane with exclusive regioselectivity. Subsequent Claisen rearrangement, ortho oxidation of the resulting phenol derivative, and mild transformation from p-quinone to p-quinone methide on a silica gel plate furnished kendomycin.


Assuntos
Rifabutina/análogos & derivados , Cromo/química , Metano/análogos & derivados , Metano/química , Rifabutina/síntese química , Rifabutina/química , Espectrofotometria Ultravioleta
18.
Phytochemistry ; 71(5-6): 648-57, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20096904

RESUMO

Ingestion of the toxic mushroom Boletus venenatus causes a severe gastrointestinal syndrome, such as nausea, repetitive vomiting, diarrhea, and stomachache. A family of isolectins (B. venenatus lectins, BVLs) was isolated as the toxic principles from the mushroom by successive 80% ammonium sulfate-precipitation, Super Q anion-exchange chromatography, and TSK-gel G3000SW gel filtration. Although BVLs showed a single band on SDS-PAGE, they were further divided into eight isolectins (BVL-1 to -8) by BioAssist Q anion-exchange chromatography. All the isolectins showed lectin activity and had very similar molecular weights as detected by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS) analysis. Among them, BVL-1 and -3 were further characterized with their complete amino acid sequences of 99 amino acids determined and found to be identical to each other. In the hemagglutination inhibition assay, both proteins failed to bind to any mono- or oligo-saccharides tested and showed the same sugar-binding specificity to glycoproteins. Among the glycoproteins examined, asialo-fetuin was the strongest inhibitor. The sugar-binding specificity of each isolectin was also analyzed by using frontal affinity chromatography and surface plasmon resonance analysis, indicating that they recognized N-linked sugar chains, especially Galbeta1-->4GlcNAcbeta1-->4Manbeta1-->4GlcNAcbeta1-->4GlcNAc (Type II) residues in N-linked sugar chains. BVLs ingestion resulted in fatal toxicity in mice upon intraperitoneal administration and caused diarrhea upon oral administration in rats.


Assuntos
Agaricales/química , Lectinas/isolamento & purificação , Lectinas de Plantas/isolamento & purificação , Sequência de Aminoácidos , Animais , Assialoglicoproteínas , Carboidratos/química , Diarreia/induzido quimicamente , Eletroforese em Gel de Poliacrilamida , Fetuínas , Glicoproteínas/química , Lectinas/química , Lectinas/toxicidade , Camundongos , Micotoxinas/química , Micotoxinas/isolamento & purificação , Micotoxinas/toxicidade , Lectinas de Plantas/química , Lectinas de Plantas/toxicidade , Ratos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , alfa-Fetoproteínas
19.
Nat Chem Biol ; 5(7): 465-7, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19465932

RESUMO

We have isolated the small, highly strained carboxylic acid cycloprop-2-ene carboxylic acid from the Asian toxic mushroom Russula subnigricans. This compound is responsible for fatal rhabdomyolysis, a new type of mushroom poisoning that is indicated by an increase in serum creatine phosphokinase activity in mice. We found that polymerization of the compound at high concentrations via ene reaction abolishes its toxicity.


Assuntos
Agaricales/química , Ácidos Carboxílicos/isolamento & purificação , Ciclopropanos/isolamento & purificação , Intoxicação Alimentar por Cogumelos/etiologia , Micotoxinas/isolamento & purificação , Rabdomiólise/etiologia , Animais , Ácidos Carboxílicos/síntese química , Ácidos Carboxílicos/toxicidade , Linhagem Celular Tumoral , Ciclopropanos/síntese química , Ciclopropanos/toxicidade , Dose Letal Mediana , Espectroscopia de Ressonância Magnética , Camundongos , Camundongos Endogâmicos ICR , Estrutura Molecular , Micotoxinas/síntese química , Micotoxinas/toxicidade
20.
J Org Chem ; 74(1): 230-43, 2009 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-19053598

RESUMO

The total synthesis of methyl sarcophytoate (1), a marine natural biscembranoid, has been achieved by the thermal Diels-Alder reaction between the 14-membered dienophile unit, methyl sarcoate (2), and the 14-membered diene unit 64. Methyl sarcoate (2) was prepared using n-BuLi-Bu(2)Mg-mediated dithiane coupling, Kosugi-Migita-Stille coupling, and Grubbs ring-closing metathesis. The diene unit 64 was prepared using Sharpless asymmetric epoxidation, Grubbs ring-closing metathesis, 6-exo-tet epoxide opening, and n-BuLi-Bu(2)Mg-mediated Ito-Kodama cyclization. The final Diels-Alder reaction between 2 and 64 proceeded with high site, endo/exo, pi-face, and regioselectivities. During this reaction, partial E --> Z isomerization at the C4 position was observed.


Assuntos
Diterpenos/síntese química , Terpenos/síntese química , Animais , Antozoários , Diterpenos/química , Conformação Molecular , Estereoisomerismo , Terpenos/química
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