Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 18 de 18
Filtrar
1.
Ann Intern Med ; 177(8): 1048-1057, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38950397

RESUMO

BACKGROUND: Acupuncture may improve degenerative lumbar spinal stenosis (DLSS), but evidence is insufficient. OBJECTIVE: To investigate the effect of acupuncture for DLSS. DESIGN: Multicenter randomized clinical trial. (ClinicalTrials.gov: NCT03784729). SETTING: 5 hospitals in China. PARTICIPANTS: Patients with DLSS and predominantly neurogenic claudication pain symptoms. INTERVENTION: 18 sessions of acupuncture or sham acupuncture (SA) over 6 weeks, with 24-week follow-up after treatment. MEASUREMENTS: The primary outcome was change from baseline in the modified Roland-Morris Disability Questionnaire ([RMDQ] score range, 0 to 24; minimal clinically important difference [MCID], 2 to 3). Secondary outcomes were the proportion of participants achieving minimal (30% reduction from baseline) and substantial (50% reduction from baseline) clinically meaningful improvement per the modified RMDQ. RESULTS: A total of 196 participants (98 in each group) were enrolled. The mean modified RMDQ score was 12.6 (95% CI, 11.8 to 13.4) in the acupuncture group and 12.7 (CI, 12.0 to 13.3) in the SA group at baseline, and decreased to 8.1 (CI, 7.1 to 9.1) and 9.5 (CI, 8.6 to 10.4) at 6 weeks, with an adjusted difference in mean change of -1.3 (CI, -2.6 to -0.03; P = 0.044), indicating a 43.3% greater improvement compared with SA. The between-group difference in the proportion of participants achieving minimal and substantial clinically meaningful improvement was 16.0% (CI, 1.6% to 30.4%) and 12.6% (CI, -1.0% to 26.2%) at 6 weeks. Three cases of treatment-related adverse events were reported in the acupuncture group, and 3 were reported in the SA group. All events were mild and transient. LIMITATION: The SA could produce physiologic effects. CONCLUSION: Acupuncture may relieve pain-specific disability among patients with DLSS and predominantly neurogenic claudication pain symptoms, although the difference with SA did not reach MCID. The effects may last 24 weeks after 6-week treatment. PRIMARY FUNDING SOURCE: 2019 National Administration of Traditional Chinese Medicine "Project of building evidence-based practice capacity for TCM-Project BEBPC-TCM" (NO. 2019XZZX-ZJ).


Assuntos
Terapia por Acupuntura , Claudicação Intermitente , Vértebras Lombares , Estenose Espinal , Humanos , Estenose Espinal/complicações , Estenose Espinal/terapia , Masculino , Feminino , Pessoa de Meia-Idade , Claudicação Intermitente/terapia , Idoso , Resultado do Tratamento , Avaliação da Deficiência
2.
J Nat Prod ; 86(5): 1360-1369, 2023 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-37159940

RESUMO

Seven new eremophilane sesquiterpenoids, paraconulones A-G (1-7), along with three previously reported analogues, periconianone D (8), microsphaeropsisin (9), and 4-epi-microsphaeropsisin (10), were obtained from an EtOAc extract of the marine-derived fungus Paraconiothyrium sporulosum DL-16. The structures of these compounds were elucidated by extensive spectroscopic and spectrometric analyses, single-crystal X-ray diffraction, and computational studies. Compounds 1, 2, and 4 are the first examples of dimeric eremophilane sesquiterpenoids coupled through a C-C bond identified from microorganisms. Compounds 2-5, 7, and 10 showed inhibitory effects on lipopolysaccharide-induced NO production in BV2 cells, which were comparable to the positive control curcumin.


Assuntos
Ascomicetos , Sesquiterpenos , Sesquiterpenos Policíclicos , Ascomicetos/química , Sesquiterpenos/farmacologia , Sesquiterpenos/química , Cristalografia por Raios X , Estrutura Molecular
3.
Soft Matter ; 16(20): 4800-4805, 2020 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-32400837

RESUMO

Peptide hydrogels show great promise as extracellular matrix mimics due to their tuneable, fibrous nature. Through incorporation of polar cationic, polar anionic or polar neutral amino acids into the Fmoc-diphenylalanine motif, we show that electrostatic charge plays a key role in the properties of the subsequent gelators. Specifically, we show that an inverse relationship exists for biocompatibility in the solution state versus the gel state for cationic and anionic peptides. Finally, we use tethered bilayer lipid membrane (tBLM) experiments to suggest a likely mode of cytotoxicity for tetrapeptides which exhibit cytotoxicity in the solution state.


Assuntos
Aminoácidos , Fluorenos , Hidrogéis , Oligopeptídeos , Aminoácidos/administração & dosagem , Aminoácidos/química , Sobrevivência Celular/efeitos dos fármacos , Fluorenos/administração & dosagem , Fluorenos/química , Células HEK293 , Humanos , Hidrogéis/administração & dosagem , Hidrogéis/química , Bicamadas Lipídicas , Oligopeptídeos/administração & dosagem , Oligopeptídeos/química , Fenilalanina/administração & dosagem , Fenilalanina/química , Eletricidade Estática
4.
Chem Biodivers ; 17(2): e1900640, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31805214

RESUMO

The extract of the strain Aspergillus flavipes DL-11 exerted antibacterial activities against six Gram-positive bacteria. During the following bioassay-guided separation, ten diphenyl ethers (1-10), two benzophenones (11-12), together with two xanthones (13-14) were isolated. Among them, 4'-chloroasterric acid (1) was a new chlorinated diphenyl ether. Their structures were elucidated by extensive spectroscopic data analysis, including IR, HR-ESI-MS, NMR experiments, and by comparison with the literature data. All compounds showed moderate to strong antibacterial effects on different Gram-positive bacteria with MIC values that ranged from 3.13 to 50 µg/mL, but none of the compounds exhibited activity against Gram-negative bacteria Vibrio parahaemolyticus ATCC17802 (MIC>100 µg/mL). In particular, the MICs of some compounds are at the level of positive control.


Assuntos
Antibacterianos/química , Aspergillus/química , Benzofenonas/química , Éteres Fenílicos/química , Xantonas/química , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Aspergillus/metabolismo , Benzofenonas/isolamento & purificação , Benzofenonas/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Conformação Molecular , Éteres Fenílicos/isolamento & purificação , Éteres Fenílicos/farmacologia , Xantonas/isolamento & purificação , Xantonas/farmacologia
5.
J Pept Sci ; 21(7): 615-9, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25998613

RESUMO

Phosphonopeptides are important phosphorus analogs of natural peptides and have been widely applied as enzyme inhibitors and antibacterial agents. A series of phosphonodipeptides containing C-terminal α-aminoalkylphosphonic acids was synthesized in satisfactory to good yields conveniently from 2-(N-benzyloxycarbonylamino)alkanamides, aldehydes, and phosphorus trichloride via Mannich-type reaction and subsequent sequential hydrolysis. The reaction mechanism was proposed and verified by (31)P NMR tracing experiments. The current method is an efficient and convenient method for preparation of phosphonopeptides containing C-terminal α-aminoalkylphosphonic acids.


Assuntos
Antibacterianos/síntese química , Inibidores Enzimáticos/síntese química , Peptídeos/síntese química , Peptidomiméticos/síntese química , Ácidos Fosforosos/química , Aldeídos/química , Amidas/química , Cloretos/química , Humanos , Hidrólise , Estrutura Molecular , Compostos de Fósforo/química
6.
Biomolecules ; 14(6)2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38927067

RESUMO

Selective staining of extracellular vesicles (EVs) is a major challenge for diagnostic and therapeutic applications. Herein, the EV labeling properties of a new class of tetranuclear polypyridylruthenium(II) complexes, Rubb7-TNL and Rubb7-TL, as phosphorescent stains are described. These new stains have many advantages over standard stains to detect and characterize EVs, including: high specificity for EV staining versus cell staining; high phosphorescence yields; photostability; and a lack of leaching from EVs until incorporation with target cells. As an example of their utility, large EVs released from control (basal) or lipopolysaccharide (LPS)-stimulated THP-1 monocytic leukemia cells were studied as a model of immune system EVs released during bacterial infection. Key findings from EV staining combined with flow cytometry were as follows: (i) LPS-stimulated THP-1 cells generated significantly larger and more numerous large EVs, as compared with those from unstimulated cells; (ii) EVs retained native EV physical properties after staining; and (iii) the new stains selectively differentiated intact large EVs from artificial liposomes, which are models of cell membrane fragments or other lipid-containing debris, as well as distinguished two distinct subpopulations of monocytic EVs within the same experiment, as a result of biochemical differences between unstimulated and LPS-stimulated monocytes. Comparatively, the staining patterns of A549 epithelial lung carcinoma-derived EVs closely resembled those of THP-1 cell line-derived EVs, which highlighted similarities in their selective staining despite their distinct cellular origins. This is consistent with the hypothesis that these new phosphorescent stains target RNA within the EVs.


Assuntos
Vesículas Extracelulares , Citometria de Fluxo , Monócitos , Humanos , Vesículas Extracelulares/metabolismo , Citometria de Fluxo/métodos , Monócitos/metabolismo , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Ácidos Nucleicos/metabolismo , Coloração e Rotulagem/métodos , Células THP-1 , Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , Lipopolissacarídeos/farmacologia , Linhagem Celular Tumoral , Células A549
7.
Heart Rhythm ; 21(5): 600-609, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38266752

RESUMO

BACKGROUND: The motion relationship and time intervals of the pulsed-wave Doppler (PWD) spectrum are essential for diagnosing fetal arrhythmia. However, few technologies currently are available to automatically calculate fetal cardiac time intervals (CTIs). OBJECTIVE: The purpose of this study was to develop a fetal heart rhythm intelligent quantification system (HR-IQS) for the automatic extraction of CTIs and establish the normal reference range for fetal CTIs. METHODS: A total of 6498 PWD spectrums of 2630 fetuses over the junction between the left ventricular inflow and outflow tracts were recorded across 14 centers. E, A, and V waves were manually labeled by 3 experienced fetal cardiologists, with 17 CTIs extracted. Five-fold cross-validation was performed for training and testing of the deep learning model. Agreement between the manual and HR-IQS-based values was evaluated using the intraclass correlation coefficient and Spearman's rank correlation coefficient. The Jarque-Bera test was applied to evaluate the normality of CTIs' distributions, and the normal reference range of 17 CTIs was established with quantile regression. Arrhythmia subset was compared with the non-arrhythmia subset using the Mann-Whitney U test. RESULTS: Significant positive correlation (P <.001) and moderate-to-excellent consistency (P <.001) between the manual and HR-IQS automated measurements of CTIs was found. The distribution of CTIs was non-normal (P <.001). The normal range (2.5th to 97.5th percentiles) was successfully established for the 17 CTIs. CONCLUSIONS: Using our HR-IQS is feasible for the automated calculation of CTIs in practice and thus could provide a promising tool for the assessment of fetal rhythm and function.


Assuntos
Arritmias Cardíacas , Coração Fetal , Frequência Cardíaca Fetal , Humanos , Feminino , Estudos Prospectivos , Gravidez , Frequência Cardíaca Fetal/fisiologia , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/fisiopatologia , Coração Fetal/diagnóstico por imagem , Coração Fetal/fisiologia , Idade Gestacional , Ultrassonografia Pré-Natal/métodos
8.
Zhongguo Zhen Jiu ; 43(6): 622-6, 2023 Jun 12.
Artigo em Chinês | MEDLINE | ID: mdl-37313554

RESUMO

OBJECTIVE: To compare the clinical efficacy of acupuncture with different frequencies in the treatment of patients with functional dyspepsia (FD). METHODS: A total of 90 patients with FD were randomly divided into a 3-time acupuncture treatment per week group (3-A group, 31 cases, 2 cases dropped off), a 1-time acupuncture treatment per week group (1-A group, 30 cases, 2 cases dropped off) and a control group (29 cases, 2 cases dropped off). In the two acupuncture groups, the acupoints were Zhongwan (CV 12) and bilateral Tianshu (ST 25), Neiguan (PC 6), Liangqiu (ST 34), Yanglingquan (GB 34), Zusanli (ST 36) and Taichong (LR 3), stimulated 3 times a week and once a week, respectively; and the treatment was given consecutively for 4 weeks. In the control group, no intervention was adopted, but the compensatory therapy was provided after the end of follow-up. The scores of the symptom index of dyspepsia (SID), self-rating anxiety scale (SAS) and self-rating depression scale (SDS) were compared among the 3 groups before treatment, after 4 weeks of treatment and in 4 and 8 weeks after treatment completion separately. The score of Nepean dyspepsia life quality index (NDLQI) was evaluated before treatment, after 2 and 4 weeks of treatment and in 4 and 8 weeks after treatment completion. RESULTS: After 4 weeks of treatment and in 4 and 8 weeks after treatment completion, the scores of SID, SAS and SDS were all reduced in the 3-A group and the 1-A group when compared with the scores before treatment (P<0.000 1, P<0.05). After 4 weeks of treatment, the scores of SID, SAS and SDS in the two acupuncture groups were lower than those in the control group (P<0.000 1). After 2 and 4 weeks of treatment, the increased values of NDLQI score in the two acupuncture groups were all higher than those in the control group (P<0.05). In 4 and 8 weeks after treatment completion, the scores of SID, SAS and SDS in the 3-A group were lower than those in the 1-A group (P<0.001, P<0.05), and the increased values of NDLQI score in the 3-A group were higher than those in the 1-A group (P<0.000 1). CONCLUSION: Acupuncture given 3 times per week is superior to the treatment given once per week in the aspects of relieving the clinical symptoms, improving the quality of life and regulating the emotional state in patients with FD. This efficacy is persistent for 8 weeks after treatment completion.


Assuntos
Terapia por Acupuntura , Dispepsia , Humanos , Dispepsia/terapia , Qualidade de Vida , Pontos de Acupuntura , Emoções
9.
Chem Commun (Camb) ; 59(45): 6877-6880, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37195631

RESUMO

A new photoluminescent polypyridylruthenium(II) stain for extracellular vesicles (EVs) released from lipopolysaccharide-stimulated THP-1 monocytes enabled important new insights into how the bacteria-induced immune system affects the blood-brain barrier (BBB). These included previously unknown aspects of EV interactions with BBB microvascular endothelial cells and the extracellular matrix relevant to human brain diseases.


Assuntos
Células Endoteliais , Vesículas Extracelulares , Humanos , Endotélio , Encéfalo , Barreira Hematoencefálica
10.
BMJ Support Palliat Care ; 12(e1): e164-e170, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-31919102

RESUMO

OBJECTIVE: To compare the efficacy of electroacupuncture (EA) in elderly and non-elderly women with stress urinary incontinence (SUI) or stress-predominant mixed urinary incontinence (MUI). METHODS: This study was a secondary analysis of two randomised controlled trials involving 252 women with SUI and 132 women with stress-predominant MUI who were treated with the same EA regimen. Elderly women were defined as those aged >60 years. The main outcome measure was the proportion of patients with ≥50% decrease in the mean 72-hour urinary incontinence episode frequency (IEF) from baseline to week 6. Overall, 1004 women were recruited in the SUI and MUI trials. In the EA group, those with urge-predominant or balanced MUI at baseline were excluded from the current study, resulting in a sample size of 384. RESULTS: Out of 384 patients with SUI or stress-predominant MUI who were treated with EA, 371 completed the study. After 6-week treatment, the proportion of women who achieved ≥50% decrease in mean 72-hour IEF from baseline was 57.3% (51/89) in the elderly group and 60.70% (173/285) in the non-elderly group; the between-group difference was not significant (3.11%, 95% CI -9.83% to 16.05%; p=0.637). Similar outcomes were observed at weeks 4, 16 and 28. Both groups showed reduction in the 72 -hour IEF, amount of urine leakage (assessed by 1-hour pad test) and International Consultation on Incontinence Questionnaire-Short Form score from baseline with no significant between-group difference. No obvious EA-related adverse events were observed during the study. CONCLUSION: EA may be an effective and safe alternative treatment for SUI or stress-predominant MUI in both elderly and non-elderly women. Age may not affect the treatment outcomes of acupuncture. TRIAL REGISTRATION NUMER: NCT01784172, NCT02047032.


Assuntos
Eletroacupuntura , Incontinência Urinária por Estresse , Incontinência Urinária , Idoso , Análise de Dados , Eletroacupuntura/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Resultado do Tratamento , Incontinência Urinária/etiologia , Incontinência Urinária por Estresse/etiologia , Incontinência Urinária por Estresse/terapia
11.
J Mater Chem B ; 8(15): 3104-3112, 2020 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-32207762

RESUMO

The ability to control the response of self-assembled systems upon exposure to external stimuli has been a long-standing goal of supramolecular chemistry. Short peptides are an attractive platform to realise this objective due to their chemical diversity and modular nature. Here, we synthesise a library of Fmoc-capped tetrapeptides, each containing two tyrosine and two lysine residues and varying in their amino acid sequence. Despite having similar secondary structure, these tetrapeptides form structures which are highly sequence dependent, yielding aggregates, nanofibres or monomers. This in turn highly affects the rate and degree of oxidative polymerisation by the enzyme tyrosinase, with self-assembled nanofibres exhibiting a greater degree of polymerisation. We monitor the formation of tyrosine oxidation products over time, finding that the precipitation of polymers is driven by quinone-based species. This affects the electrochemical properties of the oxidised peptide polymers, as determined through electrical impedance spectroscopy. Finally, intrinsic fluorescence microscale thermophoresis studies confirm that the degree of oxidative polymerisation is highly dependent on tyrosine solvent accessibility and the presence of peptide monomers. The ability to tune the kinetics of enzymatically active substrates and understand their polymerisation pathways on a molecular level is important for the creation of programmable, enzyme responsive biomaterials.


Assuntos
Lisina/metabolismo , Monofenol Mono-Oxigenase/metabolismo , Oligopeptídeos/metabolismo , Tirosina/metabolismo , Biocatálise , Técnicas Eletroquímicas , Lisina/química , Substâncias Macromoleculares/química , Substâncias Macromoleculares/metabolismo , Estrutura Molecular , Monofenol Mono-Oxigenase/química , Oligopeptídeos/química , Oxirredução , Tamanho da Partícula , Polimerização , Propriedades de Superfície , Tirosina/química
12.
Medicine (Baltimore) ; 98(38): e17160, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31567955

RESUMO

RATIONALE: Fallopian tube obstruction and diminished ovarian reserve (DOR) are main factors including female infertility. Acupuncture might be effective in the treatment of the disease. PATIENT CONCERNS: A 39-year-old woman diagnosed with fallopian tube obstruction and DOR has been unable to conceive in the past 5 years, despite of receiving various treatments and 3-time in vitro fertilization (IVF) in different countries. DIAGNOSES: Under comprehensive consideration of clinical manifestations and hysterosalpingography examinations results, the patient was diagnosed as female infertility due to fallopian tube obstruction and DOR. INTERVENTION: Electroacupuncture treatment was performed 3 times per week for about 3 months. OUTCOMES: After 2-months of electroacupuncture treatment, the patient's menstrual cycle was back to normal, and she conceived after 3-month treatment and gave birth to a healthy baby boy finally. LESSONS: Electroacupuncture might be a complementary or alternative treatment for female infertility, particularly for women with fallopian tube obstruction and DOR.


Assuntos
Eletroacupuntura , Doenças das Tubas Uterinas/complicações , Infertilidade Feminina/terapia , Reserva Ovariana , Adulto , Eletroacupuntura/métodos , Feminino , Humanos , Ciclo Menstrual , Gravidez , Complicações na Gravidez
13.
Dalton Trans ; 48(38): 14505-14515, 2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31531475

RESUMO

Linear and non-linear tetranuclear ruthenium(ii) complexes containing the bridging ligand bis[4(4'-methyl-2,2'-bipyridyl)]-1,7-heptane have been synthesised and their biological properties examined. The minimum inhibitory concentrations (MIC) and the minimum bactericidal concentrations (MBC) of the ruthenium(ii) complexes were determined against six strains of bacteria: Gram-positive Staphylococcus aureus (S. aureus) and methicillin-resistant S. aureus (MRSA); and the Gram-negative Escherichia coli (E. coli) strains MG1655, APEC, UPEC and Pseudomonas aeruginosa (P. aeruginosa). The results showed that both tetranuclear complexes had significant antimicrobial activity, with the non-linear (branched) species (Rubb7-TNL) having slightly higher activity than the corresponding linear analogue (Rubb7-TL). The corresponding toxicity against three eukaryotic cell lines - BHK (baby hamster kidney), Caco-2 (heterogeneous human epithelial colorectal adenocarcinoma) and Hep-G2 (liver carcinoma) - have also been determined. Interestingly, both Rubb7-TNL and Rubb7-TL were as toxic to the eukaryotic cells as they were to the bacteria, a rarity for kinetically-inert cationic polypyridylruthenium(ii) complexes, and exhibited lower IC50 values than cisplatin over 24-, 48- or 72-hour incubation times. Fluorescence spectroscopy was used to study the binding of the ruthenium complexes with human serum albumin (HSA). Rubb7-TNL and Rubb7-TL exhibited strong HSA binding, with equilibrium binding constants in the order of 107 M-1. Confocal microscopy was used to examine the cellular localisation of Rubb7-TNL in BHK cells. The results indicated that the ruthenium complex localised in the nucleolus. Significant accumulation was also observed in the cytoplasm, but not in the mitochondria. Taken together, the results of this study suggest that Rubb7-TNL is an unlikely candidate as an antimicrobial agent, but may have potential as an anticancer drug.


Assuntos
2,2'-Dipiridil/farmacologia , Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Complexos de Coordenação/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Heptanos/farmacologia , Piridinas/química , Rutênio/farmacologia , 2,2'-Dipiridil/química , Antibacterianos/síntese química , Antibacterianos/química , Antineoplásicos/síntese química , Antineoplásicos/química , Células CACO-2 , Proliferação de Células/efeitos dos fármacos , Complexos de Coordenação/síntese química , Complexos de Coordenação/química , Ensaios de Seleção de Medicamentos Antitumorais , Células Hep G2 , Heptanos/química , Humanos , Ligantes , Rutênio/química
14.
Front Chem ; 6: 595, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30560120

RESUMO

The toxicity (IC50) of a series of mononuclear ruthenium complexes containing bis[4(4'-methyl-2,2'-bipyridyl)]-1,n-alkane (bbn) as a tetradentate ligand against three eukaryotic cell lines-BHK (baby hamster kidney), Caco-2 (heterogeneous human epithelial colorectal adenocarcinoma) and Hep-G2 (liver carcinoma)-have been determined. The results demonstrate that cis-α-[Ru(Me4phen)(bb7)]2+ (designated as α-Me4phen-bb7, where Me4phen = 3,4,7,8-tetramethyl-1,10-phenanthroline) showed little toxicity toward the three cell lines, and was considerably less toxic than cis-α-[Ru(phen)(bb12)]2+ (α-phen-bb12) and the dinuclear complex [{Ru(phen)2}2{µ-bb12}]4+. Fluorescence spectroscopy was used to study the binding of the ruthenium complexes with human serum albumin (HSA). The binding of α-Me4phen-bb7 to the macrocyclic host molecule cucurbit[10]uril (Q[10]) was examined by NMR spectroscopy. Large upfield 1H NMR chemical shift changes observed for the methylene protons in the bb7 ligand upon addition of Q[10], coupled with the observation of several intermolecular ROEs in ROESY spectra, indicated that α-Me4phen-bb7 bound Q[10] with the bb7 methylene carbons within the cavity and the metal center positioned outside one of the portals. Simple molecular modeling confirmed the feasibility of the binding model. An α-Me4phen-bb7-Q[10] binding constant of 9.9 ± 0.2 × 106 M-1 was determined by luminescence spectroscopy. Q[10]-encapsulation decreased the toxicity of α-Me4phen-bb7 against the three eukaryotic cell lines and increased the binding affinity of the ruthenium complex for HSA. Confocal microscopy experiments indicated that the level of accumulation of α-Me4phen-7 in BHK cells is not significantly affected by Q[10]-encapsulation. Taken together, the combined results suggest that α-Me4phen-7 could be a good candidate as a new antimicrobial agent, and Q[10]-encapsulation could be a method to improve the pharmacokinetics of the ruthenium complex.

15.
Chempluschem ; 83(7): 643-650, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31950622

RESUMO

The cis-α isomer of [Ru(bb7 )(dppz)]2+ (dppz=dipyrido[3,2-a:2',3'-c]phenazine; bb7 =bis[4(4'-methyl-2,2'-bipyridyl)]-1,7-alkane) has been synthesised. The minimum inhibitory concentrations and the minimum bactericidal concentrations of [Ru(bb7 )(dppz)]2+ and its parent complex [Ru(phen)2 (dppz)]2+ (phen=1,10-phenanthroline) were determined against a range of bacteria. The results showed that both ruthenium complexes exhibited good activity against Gram-positive bacteria, but [Ru(bb7 )(dppz)]2+ showed at least eightfold better activity against the Gram-negative bacteria than [Ru(phen)2 (dppz)]2+ . Luminescence assays demonstrated that [Ru(bb7 )(dppz)]2+ accumulated in a Gram-negative bacterium to the same degree as in a Gram-positive species, and assays with liposomes showed that [Ru(bb7 )(dppz)]2+ interacted more strongly with membranes than the parent [Ru(phen)2 (dppz)]2+ complex. The DNA binding affinity for [Ru(bb7 )(dppz)]2+ was determined to be 6.7 × 106 m-1 . Although more toxic to eukaryotic cells than [Ru(phen)2 (dppz)]2+ , [Ru(bb7 )(dppz)]2+ exhibited greater activity against bacteria than eukaryotic cells.

16.
Dalton Trans ; 47(7): 2422-2434, 2018 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-29379923

RESUMO

A series of mononuclear ruthenium(ii) complexes containing the tetradentate ligand bis[4(4'-methyl-2,2'-bipyridyl)]-1,7-heptane have been synthesised and their biological properties examined. In the synthesis of the [Ru(phen')(bb7)]2+ complexes (where phen' = 1,10-phenanthroline and its 5-nitro-, 4,7-dimethyl- and 3,4,7,8-tetramethyl- derivatives), both the symmetric cis-α and non-symmetric cis-ß isomers were formed. However, upon standing for a number of days (or more quickly under harsh conditions) the cis-ß isomer converted to the more thermodynamically stable cis-α isomer. The minimum inhibitory concentrations (MIC) and the minimum bactericidal concentrations (MBC) of the ruthenium(ii) complexes were determined against six strains of bacteria: Gram-positive Staphylococcus aureus (S. aureus) and methicillin-resistant S. aureus (MRSA); and the Gram-negative Escherichia coli (E. coli) strains MG1655, APEC, UPEC and Pseudomonas aeruginosa (P. aeruginosa). The results showed that the [Ru(5-NO2phen)(bb7)]2+ complex had little or no activity against any of the bacterial strains. By contrast, for the other cis-α-[Ru(phen')(bb7)]2+ complexes, the antimicrobial activity increased with the degree of methylation. In particular, the cis-α-[Ru(Me4phen)(bb7)]2+ complex showed excellent and uniform MIC activity against all bacteria. By contrast, the MBC values for the cis-α-[Ru(Me4phen)(bb7)]2+ complex varied considerably across the bacteria and even within S. aureus and E. coli strains. In order to gain an understanding of the relative antimicrobial activities, the DNA-binding affinity, cellular accumulation and water-octanol partition coefficients (log P) of the ruthenium complexes were determined. Interestingly, all the [Ru(phen')(bb7)]2+ complexes exhibited stronger DNA binding affinity (Ka ≈ 1 × 107 M-1) than the well-known DNA-intercalating complex [Ru(phen)2(dppz)]2+ (where dppz = dipyrido[3,2-a:2',3'-c]phenazine).

17.
Int J Clin Exp Med ; 8(8): 12882-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26550204

RESUMO

This meta-analysis aimed to identify the accuracy of contrast-enhanced ultrasonography (CEUS) on the diagnosis of thyroid nodules. PubMed, Chinese Biomedical Medical databases (CNKI), Wan Fang (Chinese), and EBSCO database were searched from inception through April 15, 2015 without language and geographic restrictions. MetaDisc version 1.4 software was applied for this meta-analysis. We calculated the summary statistics for sensitivity (Sen), specificity (Spe), positive and negative likelihood ratio (LR+/LR-), diagnostic odds ratio (DOR), and receiver operating characteristic (SROC) curve. Twenty-five eligible studies were included in this meta-analysis. A total of 424 in 1154 nodules is malignant thyroid tumors. After all thyroid lesions were histologically confirmed by CEUS, the pooled Sen was 0.88 (95% confidence interval [CI] 0.85-0.91); the pooled Spe was 0.90 (95% CI 0.88-0.92). The pooled positive LR+ was 8.69(95% CI 5.78-13.09); the pooled negative LR- was 0.15 (95% CI 0.12-0.19). The pooled DOR of CEUS in the diagnosis of thyroid nodules was 63.18 (95% CI 37.82-105.53). The area under the SROC curve was 0.946 (standard error [SE] = 0.010). Our meta-analysis indicates that CEUS may have high accuracy in diagnosis the difference between benign and malignant thyroid nodules. US is a traditional tool in the diagnosis thyroid nodules. However, with the development of science and technology, the emerging of CEUS significantly improve accuracy in the diagnosis thyroid nodules.

SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa