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1.
Nature ; 625(7994): 270-275, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38200301

RESUMO

Supersolid, an exotic quantum state of matter that consists of particles forming an incompressible solid structure while simultaneously showing superfluidity of zero viscosity1, is one of the long-standing pursuits in fundamental research2,3. Although the initial report of 4He supersolid turned out to be an artefact4, this intriguing quantum matter has inspired enthusiastic investigations into ultracold quantum gases5-8. Nevertheless, the realization of supersolidity in condensed matter remains elusive. Here we find evidence for a quantum magnetic analogue of supersolid-the spin supersolid-in the recently synthesized triangular-lattice antiferromagnet Na2BaCo(PO4)2 (ref. 9). Notably, a giant magnetocaloric effect related to the spin supersolidity is observed in the demagnetization cooling process, manifesting itself as two prominent valley-like regimes, with the lowest temperature attaining below 100 mK. Not only is there an experimentally determined series of critical fields but the demagnetization cooling profile also shows excellent agreement with the theoretical simulations with an easy-axis Heisenberg model. Neutron diffractions also successfully locate the proposed spin supersolid phases by revealing the coexistence of three-sublattice spin solid order and interlayer incommensurability indicative of the spin superfluidity. Thus, our results reveal a strong entropic effect of the spin supersolid phase in a frustrated quantum magnet and open up a viable and promising avenue for applications in sub-kelvin refrigeration, especially in the context of persistent concerns about helium shortages10,11.

2.
Int J Mol Sci ; 24(17)2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37686287

RESUMO

Zinc finger protein (ZFP) transcription factors play a pivotal role in regulating plant growth, development, and response to biotic and abiotic stresses. Although extensively characterized in model organisms, these genes have yet to be reported in bamboo plants, and their expression information is lacking. Therefore, we identified 21 B-box (BBX) genes from a transcriptome analysis of Bambusa pervariabilis × Dendrocalamopsis grandis. Consequently, multiple sequence alignments and an analysis of conserved motifs showed that they all had highly similar structures. The BBX genes were divided into four subgroups according to their phylogenetic relationships and conserved domains. A GO analysis predicted multiple functions of the BBX genes in photomorphogenesis, metabolic processes, and biological regulation. We assessed the expression profiles of 21 BBX genes via qRT-PCR under different adversity conditions. Among them, eight genes were significantly up-regulated under water deficit stress (BBX4, BBX10, BBX11, BBX14, BBX15, BBX16, BBX17, and BBX21), nine under salt stress (BBX2, BBX3, BBX7, BBX9, BBX10, BBX12, BBX15, BBX16, and BBX21), twelve under cold stress (BBX1, BBX2, BBX4, BBX7, BBX10, BBX12, BBX14, BBX15, BBX17, BBX18, BBX19, and BBX21), and twelve under pathogen infestation stress (BBX1, BBX2, BBX4, BBX7, BBX10, BBX12, BBX14, BBX15, BBX17, BBX18, BBX19, and BBX21). Three genes (BBX10, BBX15, and BBX21) were significantly up-regulated under both biotic and abiotic stresses. These results suggest that the BBX gene family is integral to plant growth, development, and response to multivariate stresses. In conclusion, we have comprehensively analyzed the BDBBX genes under various adversity stress conditions, thus providing valuable information for further functional studies of this gene family.


Assuntos
Bambusa , Filogenia , Resposta ao Choque Frio , Estresse Salino , Desidratação
3.
Appl Opt ; 59(22): 6638-6641, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32749366

RESUMO

A convenient method to fabricate two-dimensional photonic quasicrystal microstructures was experimentally demonstrated by using a rotatable four-wedge prism. Two-dimensional eightfold symmetric quasicrystal microstructures are formed by two groups of twisted square lattices in a photorefractive crystal. The experimental devices of this method are simple and stable without complicated optical adjustment equipment. Optical-induced quasicrystal microstructures are analyzed and verified by magnified imaging and far-field diffraction pattern imaging. The method can be extended to fabricate more complex quasicrystal and moiré lattice microstructures. We numerically demonstrate that this method can be used to fabricate other complex photonic microstructures by using different multi-wedge prisms and adjusting the rotation angle properly.

4.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 36(6): 1032-1037, 2019 Dec 25.
Artigo em Chinês | MEDLINE | ID: mdl-31875379

RESUMO

For the researches relating to the biomedical fields such as preparation of drug micro-particulates and biomedical materials coating, according to the modular design concept and combing the piezoelectric micro-jetting technology with electromechanical engineering and automatic control technology, the drug micro-jetting multifunctional system was designed, which included the spraying support subsystem, X - Y motion platform, Z -axis subsystem and rapid installation subsystem. The drug micro-jetting multifunctional system was run and adjusted. The versatility, rationality and feasibility of this system were validated by the experiments of amoxicillin microcapsule preparation, titanium alloy drug-loaded coating preparation and balloon electrode coating preparation. It was shown that the system can be used as basic platform in multi-disciplinary cross technology research such as biomedical engineering, pharmaceutical engineering and so on.


Assuntos
Ligas , Sistemas de Liberação de Medicamentos , Eletrodos , Titânio
5.
Phys Chem Chem Phys ; 20(27): 18455-18462, 2018 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-29947383

RESUMO

A simple and efficient top-down strategy, the chemical vapor etching method, is reported for synthesizing corrugated ZnO nano/micro rods (NRs). The stabilization mechanism of this unique nanostructure has been determined through a combination of aberration-corrected field emission scanning electron microscopy, high-resolution transmission electron microscopy, and first-principles calculations. The experimental data are in good agreement with the theoretical calculations, and a remarkable nonpolar-to-polar surface faceting transition is demonstrated. The corrugated-shaped structure results from the remarkable stability of the defect-induced reconstructions (O vacancy, Zn-Zn dimer), which makes the high-index polar {303[combining macron]1} and {101[combining macron]1[combining macron]} planes lower in energy compared to the nonpolar {101[combining macron]0} plane. Based on the results of first-principles surface calculations, a general formula is established to provide an accurate description of the unusual size effect of the length of the corrugated unit vs. the NR diameter, and it also offers direct explanations for certain experimental observations. The present study deepens our atomic-level understanding of the detailed structure and stability of polar surface decorated corrugated ZnO NRs, and points to a viable path towards designing polar-stable wurtzite structures.

6.
Molecules ; 21(11)2016 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-27827969

RESUMO

The flower of Carthamus tinctorius L. (Carthami Flos, safflower), important in traditional Chinese medicine (TCM), is known for treating blood stasis, coronary heart disease, hypertension, and cerebrovascular disease in clinical and experimental studies. It is widely accepted that hydroxysafflor yellow A (HSYA) and anhydrosafflor yellow B (ASYB) are the major bioactive components of many formulae comprised of safflower. In this study, selective knock-out of target components such as HSYA and ASYB by using preparative high performance liquid chromatography (prep-HPLC) followed by antiplatelet and anticoagulation activities evaluation was used to investigate the roles of bioactive ingredients in safflower series of herb pairs. The results showed that both HSYA and ASYB not only played a direct role in activating blood circulation, but also indirectly made a contribution to the total bioactivity of safflower series of herb pairs. The degree of contribution of HSYA in the safflower and its series herb pairs was as follows: Carthami Flos-Ginseng Radix et Rhizoma Rubra (CF-GR) > Carthami Flos-Sappan Lignum (CF-SL) > Carthami Flos-Angelicae Sinensis Radix (CF-AS) > Carthami Flos-Astragali Radix (CF-AR) > Carthami Flos-Angelicae Sinensis Radix (CF-AS) > Carthami Flos-Glycyrrhizae Radix et Rhizoma (CF-GL) > Carthami Flos-Salviae Miltiorrhizae Radix et Rhizoma (CF-SM) > Carthami Flos (CF), and the contribution degree of ASYB in the safflower and its series herb pairs: CF-GL > CF-PS > CF-AS > CF-SL > CF-SM > CF-AR > CF-GR > CF. So, this study provided a significant and effective approach to elucidate the contribution of different herbal components to the bioactivity of the herb pair, and clarification of the variation of herb-pair compatibilities. In addition, this study provides guidance for investigating the relationship between herbal compounds and the bioactivities of herb pairs. It also provides a scientific basis for reasonable clinical applications and new drug development on the basis of the safflower series of herb pairs.


Assuntos
Carthamus tinctorius/química , Chalcona/análogos & derivados , Panax/química , Plantas Medicinais/química , Quinonas/análise , Anticoagulantes/farmacologia , Astragalus propinquus , Chalcona/análise , Cromatografia Líquida de Alta Pressão/métodos , Interações Medicamentosas , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Estrutura Molecular , Pigmentos Biológicos , Inibidores da Agregação Plaquetária/farmacologia
7.
Nanoscale ; 8(43): 18541-18550, 2016 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-27782247

RESUMO

The magnetic-field-induced assembly of magnetic nanoparticles (NPs) provides a unique and flexible strategy in the design and fabrication of functional nanostructures and devices. We have investigated the field-induced self-assembly of core-shell iron oxide NPs dispersed in toluene by means of small-angle neutron scattering (SANS). The form factor of the core-shell NPs was characterized and analyzed using SANS with polarized neutrons. Large-scale aggregates of iron oxide NPs formed above 0.02 T as indicated by very-small-angle neutron scattering measurements. A three-dimensional long-range ordered superlattice of iron oxide NPs was revealed under the application of a moderate magnetic field. The crystal structure of the superlattice has been identified to be face-centred cubic.

8.
Nanotechnology ; 27(29): 295601, 2016 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-27276661

RESUMO

Using the chemical vapour deposition method, we successfully converted smooth ZnO nanorods (NRs) into corrugated NRs by simply increasing the reaction time. The surface morphology and crystallographic structure of the corrugated NRs were investigated. The corrugated NRs were decorated by alternant [Formula: see text] and [Formula: see text] planes at the exposed side surfaces while the conventional [Formula: see text] planes disappeared. No twinning boundaries were found in the periodically corrugated structures, indicating that they were type II corrugated NRs. Further investigation told us that they were selectively etched. We introduced a hydrothermal method to synthesize the smooth ZnO NRs and then etched them in a tube furnace at 950 °C with a flow of carbon monoxide. By separating the growth stage and the selective etching stage, we explicitly demonstrated a successfully selective etching effect on ZnO NRs with a carbon monoxide reducing atmosphere for the first time. An etching mechanism based on the selective reaction between carbon monoxide and the different exposed surfaces was proposed. Our results will improve the understanding of the growth mechanism on coarse or corrugated NRs and provide a new strategy for the application of surface controlled nanostructured materials.

9.
Appl Opt ; 55(9): 2301-5, 2016 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-27140566

RESUMO

Currently, most transducers in photoacoustic endoscopy (PAE) are ceramic based, which are complicated to fabricate and are expensive. In this work, we have for the first time presented a hollow structured epoxy lens-focused transducer that was based on a 52 µm thick polyvinylidine fluoride (PVDF) film for the purpose of PAE imaging. Intensive field characteristic tests were performed on transducers with different lens curvatures, and results show that with the 6 mm fixed aperture, a lateral resolution less than 0.5 mm can be obtained with a focal length around 19 mm, which is close to the theoretical calculations. The PAE application of the built transducer was also demonstrated with phantom experiments. Compared with the commonly used ceramic-based transducers, the proposed method has greatly reduced the design and fabrication cost of the hollow structured focused transducer as required in PAE, and facilitated the development of the PAE system in lab conditions. The built transducer may play an important role in the PAE imaging of some relatively large human structures and organs, such as the gastrointestinal tract and the cervical canal.

10.
Int J Clin Exp Pathol ; 8(5): 5026-34, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26191196

RESUMO

OBJECTIVE: To investigate the cytoprotective effects of high dose of α-galactosylceramide (α-GC) on the activation-induced CD4+ T and CD8+ T cell death. METHODS: Experimental autoimmune encephalomyelitis (EAE) was induced using adoptive transfer of MOGCD4+ cells treated using α-GC into recipient C57BL/6 mice while the MOGCD4+ cells treated using 0.5% polysorbate were set as vehicle group, based on which to investigate the effects of α-GC on activation induced CD4+ T cell death. Additionally, an EG7 tumor-bearing mice model is established using adoptive transfer of CD8+ T cells, based on which to investigate the effect of α-GC on the apoptosis of CD8+ T cells. RESULTS: A higher induction rate was noticed after adoptive transfer of MOGCD4+ cells treated using α-GC together with the severity of EAE compared with the conventional methods. Longer survival duration was noted in the green fluorescent protein (GFP) labeled MOGT in the α-GC group compared with the vehicle group (P < 0.05). Severe inflammatory cell infiltration and myelinoclasis was noted in the white matter of nervous system in the α-GC group. In the EG7 tumor model, more adoptive CD8+ T cells were survived in α-GC group compared with that of vehicle group. The growth of tumor mass was significantly inhibited in α-GC group. CONCLUSIONS: high dose of α-GC could be used as an adjuvant for inhibiting activation-induced CD4+ T and CD8+ T cell death. Our study could provide helpful information for the development of adoptive cell therapy with reduced programmed cell death.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Apoptose/efeitos dos fármacos , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/efeitos dos fármacos , Encefalomielite Autoimune Experimental/tratamento farmacológico , Galactosilceramidas/administração & dosagem , Linfócitos do Interstício Tumoral/efeitos dos fármacos , Medula Espinal/efeitos dos fármacos , Transferência Adotiva , Animais , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD4-Positivos/transplante , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/patologia , Citoproteção , Encefalomielite Autoimune Experimental/imunologia , Encefalomielite Autoimune Experimental/patologia , Ativação Linfocitária/efeitos dos fármacos , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/patologia , Masculino , Camundongos Endogâmicos C57BL , Glicoproteína Mielina-Oligodendrócito/imunologia , Medula Espinal/imunologia , Medula Espinal/patologia , Fatores de Tempo
11.
J Med Case Rep ; 8: 367, 2014 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-25394500

RESUMO

INTRODUCTION: Brucellosis is a systemic infectious disease which is still a challenging medical problem in rural areas such as northern China. It rarely occurs in urban areas such as Shenzhen in southern China. Osteoarticular involvements are frequently seen in brucellosis, and rarely is arthritis the only clinical presentation. We report a case of hip septic arthritis caused by Brucella melitensis in an urban area of Shenzhen, China. CASE PRESENTATION: A 29-year-old Chinese woman, Han ethnical group presented to our hospital with left hip pain persisting for one month. She had a history of contact with goats one month before admission. Her clinical examination showed marked tenderness and limited movement of her left hip. Further imaging showed effusion of her left hip joint. Inflammatory markers including erythrocyte sedimentation rate (ESR) and c-reactive protein (CRP) were raised. Our clinical diagnosis was septic arthritis of the left hip. A left hip arthroscopy was performed and the culture was positive for Brucella melitensis. She returned to normal activity after completing a standard antibiotic regimen, including gentamicin at 120mg daily for 2 weeks, doxycycline at 100mg daily and rifampicin at 450mg for a total of 12 weeks. CONCLUSIONS: Brucellosis is endemic in some rural areas of China, but rare in urban areas such as Shenzhen in southern China. However, more cases will be expected in urban areas due to increasing migration within China. Physicians should consider brucellosis as one of the differential diagnosis of arthritis. Early surgical intervention is recommended to prevent further joint destruction.


Assuntos
Artrite Infecciosa/microbiologia , Brucelose/diagnóstico , Adulto , Antibacterianos/uso terapêutico , Artrite Infecciosa/tratamento farmacológico , Biomarcadores/sangue , Brucella melitensis , Brucelose/tratamento farmacológico , China , Diagnóstico Diferencial , Quimioterapia Combinada , Feminino , Quadril , Humanos
12.
Int Orthop ; 37(6): 1165-70, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23503697

RESUMO

PURPOSE: Pigmented villonodular synovitis (PVNS) is a relatively rare, benign proliferation lesion of the synovium of large joints, but there is not much information available about the disease's aetiology, clinical history, differential diagnosis, treatment, and long-term effects. We conducted a study to analyse these aspects of PVNS. METHODS: We reviewed all clinical data for 75 patients with PVNS (81 joints) who were treated either by synovectomy alone or synovectomy plus arthroplasty. RESULTS: In all cases, the diagnosis of PVNS was confirmed by pathological examination. The ratio of males to females was 27:48, and the average age of patients was 46 years (range, 15-80 years). Lesions were located in the knee, hip, or ankle, and pain and swelling were the main symptoms. Of 75 patients, 42 had a history of trauma to the involved joint. Forty-one patients (43 joints) underwent synovectomy alone, and 34 patients (38 joints) underwent synovectomy and arthroplasty together. Of the 75 patients, 61 had full follow-up data. Twelve patients had recurrent legions detected by pathological examinations; four patients had more than two recurrences. Moreover, five patients developed PVNS after arthroplasty. CONCLUSIONS: PVNS occurs most often in middle-aged women and most frequently involves the knee, followed by the hip and ankle. The disease's etiology is varied and unclear. Surgical excision alone or with arthroplasty is an effective treatment, but there is a high rate of recurrence.


Assuntos
Articulação do Tornozelo , Articulação do Quadril , Articulação do Joelho , Sinovite Pigmentada Vilonodular , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Articulação do Tornozelo/diagnóstico por imagem , Articulação do Tornozelo/cirurgia , Artroplastia , Criança , Feminino , Articulação do Quadril/diagnóstico por imagem , Articulação do Quadril/cirurgia , Humanos , Articulação do Joelho/diagnóstico por imagem , Articulação do Joelho/cirurgia , Masculino , Pessoa de Meia-Idade , Procedimentos Ortopédicos , Radiografia , Estudos Retrospectivos , Sinovectomia , Membrana Sinovial/diagnóstico por imagem , Sinovite Pigmentada Vilonodular/diagnóstico , Sinovite Pigmentada Vilonodular/etiologia , Sinovite Pigmentada Vilonodular/cirurgia , Resultado do Tratamento , Adulto Jovem
13.
J Inflamm Res ; 5: 117-23, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23204851

RESUMO

BACKGROUND AND METHODS: It has been reported that C/T dimorphism at position 1418 of the thrombomodulin gene causes a cytosine (C) transition to thymidine (T), resulting in an alanine (A) to valine (V) substitution at amino acid position 455 (TM455). TM455 had been found not only in African American and American whites, but also in whites in The Netherlands and Sweden. Among these populations, the C/C genotype is predominant, although the distribution of this dimorphism is different. Thrombomodulin is an important anticoagulant protein that is downregulated in endothelial cells overlying atherosclerotic plaques and is also an anti-inflammatory molecule. TM455 is located in the last epidermal growth factor-like repeat of thrombomodulin, which is functionally important for protein C activation and thrombin binding. The distribution of thrombomodulin polymorphism and association between TM455, inflammatory cytokines, and carotid atherosclerosis in the Chinese Han population is unclear. METHODS: This thrombomodulin dimorphism was analyzed by allele-specific amplification in 144 patients with carotid atherosclerosis and in 384 healthy controls. TM455 was found in the Chinese Han population, but the genotype frequency and distribution of each genotype in this population differed substantially from that in other ethnic subgroups. The C/T and T/T genotypes were predominant in the Chinese Han population, and the frequency of the T allele in this population (63.8%) was much higher than that in whites in The Netherlands (18%), Sweden (26.1%), and the US (18.4%), and in blacks in the US (7.6%). The frequencies of these single nucleotide polymorphisms complied well with the Hardy-Weinberg equilibrium in healthy individuals. The C allele was significantly more common among patients with carotid atherosclerosis than in controls (P < 0.05). The frequency of the C allele was 45.5% in patients and 36.2% in controls. The thrombomodulin Ala455 genotypes C/C and C/T were significantly more common than the T/T genotype in patients with carotid atherosclerosis in the Chinese Han population. In addition, higher baseline levels of tumor necrosis factor alpha (55.45 ± 11.58 pg/mL versus 52.70 ± 10.74 pg/mL; P < 0.05), interleukin-6 (31.53 ± 10.51 pg/mL versus 27.73 ± 8.37 pg/mL; P < 0.01), and C-reactive protein (6.65 ± 2.01 mg/L versus 4.06 ± 1.03 mg/L; P < 0.01) were observed in patients with carotid atherosclerosis than in controls. Interestingly, compared with baseline inflammatory cytokine levels in those with the Val/Val genotype, higher baseline tumor necrosis factor alpha, interleukin-6, and C-reactive protein levels were observed for the Ala/Ala genotype in both patients with carotid atherosclerosis and healthy controls. CONCLUSION: Our results support a significant association between thrombomodulin Ala455Val dimorphism, inflammatory cytokines, and carotid atherosclerosis in the Chinese Han population.

14.
Microsurgery ; 30(5): 380-5, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20641096

RESUMO

Although success of digital replantations in children has been reported by many authors, the very distal fingertip replantation remains technically demanding. The aim of this article is to review our experience with fingertip replantations at or distal to the nail base in pediatric patients and evaluate the clinical outcomes. From October 2000 to May 2007, 12 pediatric fingertips amputated at or distal to the nail base were replanted. Only one artery was anastomosed for revascularization with or without nerve repair; vein drainage was provided by the controlled bleeding technique. Eleven of the 12 replants (91%) survived; one replant of crushed digit failed. An average of 26 month (range, 6 to 36 months) follow-up revealed excellent restoration of finger motion and appearance. The regained static 2-point discrimination (S2PD) sensation was from 3.2 to 5.0 mm (mean, 4.2 mm). Both the parents and the children were satisfied with the final results. In conclusion, fingertip replantation in children allows good functional and esthetical recovery and should be attempted if technically feasible.


Assuntos
Amputação Traumática/cirurgia , Traumatismos dos Dedos/cirurgia , Microcirurgia , Reimplante , Fatores Etários , Amputação Traumática/etiologia , Amputação Traumática/patologia , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Traumatismos dos Dedos/etiologia , Traumatismos dos Dedos/patologia , Humanos , Masculino , Unhas , Estudos Retrospectivos , Resultado do Tratamento
15.
Tetrahedron Lett ; 49(6): 937-940, 2008 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-19197341

RESUMO

Novel semisynthetic analogs of salvinorin A, a full agonist having extraordinary affinity as well as selectivity for the κ-opioid receptor (KOR), were obtained in good yields. The derivatives are remarkable for their unusual and unique hemiacetal structure in the salvinorin series of compounds. The formation of the hemiacetal occurs with epimerization at C-12, thus preserving the original configuration of salvinorin A. The dimethyl ester derivative of the hemiacetal was found to have an affinity for both KOR and MOR (µ-opioid receptor).

16.
J Nat Prod ; 69(4): 704-6, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16643059

RESUMO

Two new, 5-heptadeca-8'Z,11'Z,16-trienylresorcinol (1) and 5-heptadeca-9'E,11'Z,16-trienylresorcinol (2), and six known 5-alkylresorcinols (3-8) were isolated from the mushroom Merulius incarnatus. Compound 2 is the first 5-alkylresorcinol derivative that contains a trans-cis conjugated double bond system. Compounds 1, 2, 5, 6, 7, and 8 were found to inhibit methacillin-resistant Staphylococcus aureus (MRSA) with IC(50) values of 2.5, 15, 9.5, 8.0, 5.0, and 6.5 microg/mL, respectively. Compound 1 was also active against leishmania, with an IC(50) value of 3.6 microg/mL, and showed no cytotoxicity in our Vero cell test up to a concentration of 25 microg/mL. The structures of these isolates were determined by spectroscopic data including 1D and 2D NMR.


Assuntos
Agaricales/química , Anti-Infecciosos , Leishmania/efeitos dos fármacos , Resorcinóis , Animais , Anti-Infecciosos/química , Anti-Infecciosos/isolamento & purificação , Anti-Infecciosos/farmacologia , Candida albicans/efeitos dos fármacos , Chlorocebus aethiops , Concentração Inibidora 50 , Resistência a Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Resorcinóis/química , Resorcinóis/isolamento & purificação , Resorcinóis/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Estereoisomerismo , Células Vero
17.
Phytochem Anal ; 16(3): 222-30, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15997857

RESUMO

An HPLC-UV-MS method for the analysis of aristolochic acids A, B, C and D, 7-OH-aristolochic acid A, and aristolic acid in a number of plant materials and their commercial products has been developed. HPLC with photodiode array detection and electrospray ionisation-MS in the selected ion monitoring mode allowed the identification of the target compounds and increased the selectivity of complex analyses such as those associated with multi-botanical preparations. The presented method was used to analyse 10 plant samples and six commercial products that possibly contained aristolochic acids. The resulting chromatographic profiles of the samples were significantly different from each other, and the method was directly transferred to HPLC-MS, which was used to confirm the presence of the six aristolochic acids mentioned above.


Assuntos
Ácidos Aristolóquicos/análise , Medicamentos de Ervas Chinesas/análise , Plantas Medicinais/química , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina , Raízes de Plantas/química , Espectrometria de Massas por Ionização por Electrospray , Espectrofotometria Ultravioleta
18.
Chem Pharm Bull (Tokyo) ; 52(10): 1246-8, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15467246

RESUMO

Phytochemical study of the ethanol extract of the seeds of Aesculus chinensis led to the isolation of a new triterpenoid saponin (6), together with five known triterpenoid saponins (1-5). The structure of the new compound was elucidated on the basis of spectral data to be 21,28-di-O-acetylprotoaescigenin-3-O-[beta-D-glucopyranosyl(1-2)][beta-D-glucopyranosyl(1-4)]-beta-D-glucopyranosiduronic acid (aesculiside A, 6). The antiinflammatory activities of the four main saponins (1-4) were compared with those of total saponin extracts, and single saponins showed more potent activity than total saponin extracts in mice.


Assuntos
Aesculus , Anti-Inflamatórios/farmacologia , Saponinas/farmacologia , Triterpenos/farmacologia , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Edema/induzido quimicamente , Edema/tratamento farmacológico , Feminino , Espectroscopia de Ressonância Magnética , Masculino , Camundongos , Estrutura Molecular , Extratos Vegetais , Saponinas/química , Saponinas/isolamento & purificação , Sementes , Triterpenos/química , Triterpenos/isolamento & purificação , Xilenos/efeitos adversos
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