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1.
Ann Clin Microbiol Antimicrob ; 23(1): 23, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38449006

RESUMO

BACKGROUND: The aim of this study was to investigate the clinical features of Nocardia infections, antibiotic resistance profile, choice of antibiotics and treatment outcome, among others. In addition, the study compared the clinical and microbiological characteristics of nocardiosis in bronchiectasis patients and non-bronchiectasis patients. METHODS: Detailed clinical data were collected from the medical records of 71 non-duplicate nocardiosis patients from 2017 to 2023 at a tertiary hospital in Zhengzhou, China. Nocardia isolates were identified to the species level using MALDI-TOF MS and 16S rRNA PCR sequencing. Clinical data were collected from medical records, and drug susceptibility was determined using the broth microdilution method. RESULTS: Of the 71 cases of nocardiosis, 70 (98.6%) were diagnosed as pulmonary infections with common underlying diseases including bronchiectasis, tuberculosis, diabetes mellitus and chronic obstructive pulmonary disease (COPD). Thirteen different strains were found in 71 isolates, the most common of which were N. farcinica (26.8%) and N. cyriacigeorgica (18.3%). All Nocardia strains were 100% susceptible to both TMP-SMX and linezolid, and different Nocardia species showed different patterns of drug susceptibility in vitro. Pulmonary nocardiosis is prone to comorbidities such as bronchiectasis, diabetes mellitus, COPD, etc., and Nocardia is also frequently accompanied by co-infection of the body with pathogens such as Mycobacterium and Aspergillus spp. Sixty-one patients underwent a detailed treatment regimen, of whom 32 (52.5%) received single or multi-drug therapy based on TMP-SMX. Bronchiectasis was associated with a higher frequency of Nocardia infections, and there were significant differences between the bronchiectasis and non-bronchiectasis groups in terms of age distribution, clinical characteristics, identification of Nocardia species, and antibiotic susceptibility (P < 0.05). CONCLUSIONS: Our study contributes to the understanding of the species diversity of Nocardia isolates in Henan, China, and the clinical characteristics of patients with pulmonary nocardiosis infections. Clinical and microbiologic differences between patients with and without bronchiectasis. These findings will contribute to the early diagnosis and treatment of patients.


Assuntos
Bronquiectasia , Diabetes Mellitus , Nocardiose , Nocardia , Doença Pulmonar Obstrutiva Crônica , Humanos , Nocardia/genética , RNA Ribossômico 16S/genética , Combinação Trimetoprima e Sulfametoxazol , Nocardiose/tratamento farmacológico , China , Bronquiectasia/tratamento farmacológico , Resistência a Medicamentos
2.
Ann Noninvasive Electrocardiol ; 29(2): e13110, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38339802

RESUMO

A 50-year-old female patient, presented with repeated syncope for more than 2 years. Prior assessments were conducted at different hospitals, but no definite abnormalities were found. The patient's fear and anxiety about possible future attacks were escalating. Through a Head-up tilt test, the cause was finally identified as vasovagal syncope. Following a 5-min administration of nitroglycerin, the patient reported palpitations, nausea, and deep, rapid breathing. The electrocardiogram initially showed a first-degree atrioventricular block, progressing swiftly to a second-degree type I atrioventricular block-high atrioventricular block. Immediate intervention was undertaken, but blood pressure was not instantly ascertainable, coinciding with an abrupt loss of consciousness. Subsequent electrocardiographic findings included paroxysmal third-degree atrioventricular block, sinus arrest, and complete cardiac arrest, prompting the initiation of external cardiac compressions. The longest recorded ventricular arrest approximated 15 s, with sinus rhythm resuming post 10 s of cardiac compressions and the patient regaining consciousness. The patient underwent vagal ablation and no longer experienced syncope.


Assuntos
Bloqueio Atrioventricular , Síncope Vasovagal , Pessoa de Meia-Idade , Humanos , Feminino , Bloqueio Atrioventricular/complicações , Eletrocardiografia/efeitos adversos , Síncope/diagnóstico , Síncope/etiologia , Síncope/terapia , Síncope Vasovagal/diagnóstico , Síncope Vasovagal/terapia , Síncope Vasovagal/complicações , Arritmias Cardíacas/complicações , Teste da Mesa Inclinada
3.
Nat Commun ; 15(1): 119, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38168072

RESUMO

The sophisticated hierarchical structure that precisely combines contradictory mechanical and biological characteristics is ideal for biomaterials, but it is challenging to achieve. Herein, we engineer a spatiotemporally hierarchical guided bone regeneration (GBR) membrane by rational bilayer integration of densely porous N-halamine functionalized bacterial cellulose nanonetwork facing the gingiva and loosely porous chitosan-hydroxyapatite composite micronetwork facing the alveolar bone. Our GBR membrane asymmetrically combine stiffness and flexibility, ingrowth barrier and ingrowth guiding, as well as anti-bacteria and cell-activation. The dense layer has a mechanically matched space maintenance capacity toward gingiva, continuously blocks fibroblasts, and prevents bacterial invasion with multiple mechanisms including release-killing, contact-killing, anti-adhesion, and nanopore-blocking; the loose layer is ultra-soft to conformally cover bone surfaces and defect cavity edges, enables ingrowth of osteogenesis-associated cells, and creates a favorable osteogenic microenvironment. As a result, our all-in-one porous membrane possesses full protective abilities in GBR.


Assuntos
Regeneração Óssea , Membranas Artificiais , Porosidade , Regeneração Óssea/fisiologia , Osteogênese , Materiais Biocompatíveis/química
4.
Adv Mater ; : e2305400, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38010313

RESUMO

Wet-adhesive hydrogels have been developed as an attractive strategy for tissue repair. However, achieving simultaneously low swelling and high burst pressure tolerance of wet-adhesive hydrogels is crucial for in vivo application which remains challenges. Herein, a novel super-structured porous hydrogel (denoted as PVA/PAAc-N+ ) is designed via facile moisture-induced phase separation-solvent exchange process for obtaining porous polyvinyl alcohol (PVA) hydrogel as dissipative layer and in situ photocuring technology for entangling quaternary ammonium-functionalized poly(acrylic acid)-based wet-adhesive layer (PAAc-N+ ) with the porous surface of PVA layer. Benefitting from the ionic crosslinking between quaternary ammonium ions and carboxylate ions in PAAc-N+ wet-adhesive layer as well as the high crystallinity induced by abundant hydrogen bonds of PVA layer, the hydrogel has unique ultralow swelling property (0.29) without sacrificing adhesion strength (63.1 kPa). The porous structure of PVA facilitates the mechanical interlock at the interface between PAAc-N+ wet-adhesive layer and tough PVA dissipative layer, leading to the ultrahigh burst pressure tolerance up to 493 mm Hg and effective repair for porcine heart rupture; the PVA layer surface of PVA/PAAc-N+ hydrogel can prevent postoperative adhesion. By integrating ultralow swelling, ultrahigh burst pressure tolerance, and anti-postoperative adhesion properties, PVA/PAAc-N+ hydrogel shows an appealing application prospect for tissue repair.

5.
J Thorac Dis ; 15(9): 5006-5019, 2023 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-37868891

RESUMO

Background: Lung adenocarcinoma (LUAD) is the most common subtype of non-small cell lung cancer (NSCLC). Chemotherapy resistance is the main cause of chemotherapy failure. Cullin7 (Cul7) is highly expressed in LUAD and is associated with poor prognosis. Moreover, Cul7 is abnormally overexpressed in docetaxel-resistant LUAD cells. Therefore, further exploration of the role and molecular mechanism of Cul7 in LUAD docetaxel resistance is necessary. Methods: We established docetaxel-resistant cell lines (A549DTX and H358DTX cell lines) by exposing cells to gradually increasing concentrations of docetaxel. Cell (A549, A549DTX, H358, and H358DTX cell lines) sensitivity to docetaxel was determined via a 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymmethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium, inner salt (MTS) assay. And then quantitative polymerase chain reaction (qPCR) and Western blotting were performed to measure the expression of Cul7 and Survivin in A549, A549DTX, H358, and H358DTX cell lines. Subsequently, we knocked down Cul7 in docetaxel-resistant cells and overexpressed Cul7 in parental cells via lentiviral transduction to further validate the correlation between Cul7 and docetaxel resistance, while exploring the molecular mechanism of docetaxel resistance it caused. Immunofluorescence and immunohistochemical (IHC) staining were also used to evaluate the expression and cellular localization of Cul7. To confirm the effect of Cul7 expression on cell apoptosis, we used flow cytometry to detect the apoptosis rate of A549 and A549DTX cells with the same drug concentration. Results: Cul7 was highly expressed in A549DTX and H358DTX cells. However, when Cul7 expression was knocked down in A549DTX and H358DTX cells, cell sensitivity to docetaxel was significantly increased. In addition, we found that Cul7 was coexpressed with Survivin. Silencing Survivin reversed the docetaxel insensitivity caused by Cul7 overexpression. High expression of Cul7 and Survivin in docetaxel-resistant LUAD cells inhibited the intrinsic apoptosis pathway and promoted cell proliferation. Therefore, the Cul7/Survivin axis may play a role in inducing LUAD docetaxel chemoresistance. Conclusions: Cul7 and Survivin were both highly expressed in docetaxel-resistant LUAD cells. Our results suggest that Cul7 may inhibit apoptosis and promote the proliferation of LUAD cells by increasing the Survivin protein level, which in turn contributes to docetaxel chemoresistance in LUAD.

6.
Comput Biol Med ; 166: 107479, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37783074

RESUMO

OBJECTIVE: Chronic heart failure (CHF) is a complicated clinical syndrome with a high mortality rate. XiJiaQi (XJQ) is a traditional Chinese medicine used in the clinical treatment of CHF, but its bioactive components and their modes of action remain unknown. This study was designed to unravel the molecular mechanism of XJQ in the treatment of CHF using multiple computer-assisted and experimental methods. METHODS: Pharmacoinformatics-based methods were used to explore the active components and targets of XJQ in the treatment of CHF. ADMETlab was then utilized to evaluate the pharmacokinetic and toxicological properties of core components. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were to explore the underlying mechanism of XJQ treatment. Molecular docking, surface plasmon resonance (SPR), and molecular dynamics (MD) were employed to evaluate the binding of active components to putative targets. RESULTS: Astragaloside IV, formononetin, kirenol, darutoside, periplocin and periplocymarin were identified as core XJQ-related components, and IL6 and STAT3 were identified as core XJQ targets. ADME/T results indicated that periplocin and periplocymarin may have potential toxicity. GO and KEGG pathway analyses revealed that XJQ mainly intervenes in inflammation, apoptosis, diabetes, and atherosclerosis-related biological pathways. Molecular docking and SPR revealed that formononetin had a high affinity with IL6 and STAT3. Furthermore, MD simulation confirmed that formononetin could firmly bind to the site 2 region of IL6 and the DNA binding domain of STAT3. CONCLUSION: This study provides a mechanistic rationale for the clinical application of XJQ. Modulation of STAT3 and IL-6 by XJQ can impact CHF, further guiding research efforts into the molecular underpinnings of CHF.

7.
Clin Exp Hypertens ; 45(1): 2224952, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37337968

RESUMO

AIMS: To explore the relationship between diurnal blood pressure (BP) pattern and season. METHODS: A total of 6765 eligible patients (average age 57.35 ± 15.53 years; male 51.8%; hypertensives 68.8%) from 1 October 2016 to 6 April 2022 were enrolled, who were divided into four dipper groups, dipper, non-dipper, riser, and extreme-dipper, according to the diurnal BP pattern calculated using their ambulatory BP monitoring data. The season which the patient was in was determined by the time of ambulatory BP monitoring examination. RESULTS: Among the 6765 patients, 2042 (31.18%) were grouped into dipper, 380 (5.6%) into extreme-dipper, 1498 (22.1%) into riser and 2845 (42.1%) into non-dipper. Only the dipper subjects showed age difference among seasons, with the average age significantly lower in winter. There was no seasonal difference in age for the other types. No seasonal difference was revealed in gender, BMI, hypertension or not. Diurnal BP patterns significantly differed among seasons (P < .001). Post hoc tests with Bonferroni correction indicated the significantly different diurnal BP pattern between any two seasons (P < .001), but not between spring and autumn (P = .257), and the significance of the P value was assessed at 0.008 (0.05/6) after Bonferroni correction. Multinomial logistic regression suggested season as an independent contributor to diurnal BP pattern. CONCLUSION: Diurnal BP pattern is influenced by season.


Assuntos
Ritmo Circadiano , Hipertensão , Humanos , Masculino , Adulto , Pessoa de Meia-Idade , Idoso , Pressão Sanguínea/fisiologia , Estações do Ano , Ritmo Circadiano/fisiologia , Fatores de Risco , Monitorização Ambulatorial da Pressão Arterial
8.
Adv Sci (Weinh) ; 10(16): e2206981, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37029705

RESUMO

In guided bone regeneration surgery, a barrier membrane is usually used to inhibit soft tissue from interfering with osteogenesis. However, current barrier membranes usually fail to resist the impact of external forces on bone-augmented region, thus causing severe displacement of membranes and their underlying bone graft materials, eventually leading to unsatisfied bone augmentation. Herein, a new class of local double-layered adhesive barrier membranes (ABMs) is developed to successfully immobilize bone graft materials. The air-dried adhesive hydrogel layers with suction-adhesion properties enable ABMs to firmly adhere to the wet bone surface through a "stick-and-use" band-aid-like strategy and effectively prevent the displacement of membranes and the leakage of bone grafts in uncontained bone defect treatment. Furthermore, the strategy is versatile for preparing diverse adhesive barrier membranes and immobilizing different bone graft materials for various surgical regions. By establishing such a continuous barrier for the bone graft material, this strategy may open a novel avenue for designing the next-generation barrier membranes.


Assuntos
Regeneração Óssea , Osteogênese , Transplante Ósseo
9.
Clin Lab ; 68(12)2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36546752

RESUMO

BACKGROUND: As a common pediatric respiratory disease, Mycoplasma pneumoniae pneumonia (MPP) accounts for 20 - 30% of acquired pneumonia in children, with a rising morbidity rate annually. We aimed to explore the correlations of different serological parameters with the severity and prognosis of MPP children. METHODS: A total of 108 MPP children were divided into severe group (n = 58) and mild group (n = 50). The serum levels of triglycerides, HDL-C, LDL-C, erythrocyte sedimentation rate (ESR), D-dimer (DD), lactate dehydrogenase (LDH), interleukin-6 (IL-6), galectin-3 (Gal-3), homocysteine (Hcy), and procalcitonin (PCT) were measured. Receiver operating characteristic (ROC) curves were plotted to analyze their predictive values for poor prognosis. They were followed up for 6 months and assigned into good and poor prognosis groups. Multivariate logistic regression analysis was performed to explore the serological parameters affecting prognosis. A prediction model was established. RESULTS: In acute and recovery phases, the levels of ESR, DD, LDH, IL-6, Gal-3, Hcy, and PCT in the severe group were significantly higher than those in the mild group (p < 0.05). Prediction combining various serological parameters had the highest value for poor prognosis. ESR, DD, LDH, IL-6, Gal-3, Hcy, and PCT levels were independent risk factors. The concordance index of the nomogram model established using these factors was 0.745 (95% CI: 0.684 - 0.830). The area under the ROC curve was 0.726 (95% CI: 0.701 - 0.815). The predicted probability of the model was consistent with the actual one, showing high accuracy. CONCLUSIONS: Serum levels of ESR, DD, LDH, IL-6, Gal-3, Hcy, and PCT are closely correlated with the severity and prognosis of MPP children, which provide references for prognostic evaluation. Prediction combining these indices is more valuable than that using a single index.


Assuntos
Mycoplasma pneumoniae , Pneumonia por Mycoplasma , Humanos , Criança , Interleucina-6 , Prognóstico , Pneumonia por Mycoplasma/diagnóstico , Pró-Calcitonina , L-Lactato Desidrogenase , Estudos Retrospectivos
10.
BMJ Open ; 12(5): e051794, 2022 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-35613778

RESUMO

OBJECTIVE: To compare the effectiveness and safety of the six interventions for neovascular glaucoma. DESIGN: A systematic review and network meta-analysis. METHODS: Randomised controlled trials and cohort studies which compared the six interventions in neovascular glaucoma were identified using the following databases searched up to 1 September 2020: PubMed, Cochrane Library, Embase and Web of Science. The quality assessment was conducted by using the Cochrane risk of bias tool and the Newcastle-Ottawa scale. The primary outcome measure was the weighted mean differences for intraocular pressure reduction. Secondary one was ORs for success rate. Outcome measures were reported with a 95% CI and p<0.05 was considered statistically significant. Network meta-analysis was performed using Stata V.15.0. RESULTS: Twenty-three studies involving a total of 1303 patients were included. The types of surgical treatments included Ahmed glaucoma valve (AGV) implant surgery, AGV combined with intravitreal anti-vascular endothelial growth factor (AGV +IVAV), cyclophotocoagulation (CPC), cyclocryotherapy (CCT), trabeculectomy with mitomycin (Trab(MMC)) and Trab(MMC) combined with IVAV (Trab(MMC)+IVAV). Network meta-analysis showed that in comparison with AGV, AGV +IVAV (MD=4.74, 95% CI 1.04 to 8.45) and Trab(MMC)+IVAV (MD=6.19, 95% CI 0.99 to 11.40) showed a favourable effect in intraocular pressure reduction (IOPR) 6 months after surgery. Compared with CCT, AGV (OR=-0.17, 95% CI -0.53 to -0.05), AGV +IVAV (OR=-0.10, 95% CI -3.48 to -1.19), CPC (OR=-0.12, 95% CI -0.53 to -0.05), Trab(MMC) (OR=3.54, 95% CI 1.15 to 10.91) and Trab(MMC)+IVAV (OR=5.78, 95% CI 2.29 to 14.61) showed a superior impact in success rate. The order of efficacy as best intervention ranked as follows: Trab(MMC)+IVAV (IOPR 6 months after surgery, surface under the cumulative ranking (SUCRA)=88.1), CPC (IOPR 12 months after surgery, SUCRA=81.9), AGV +IVAV (IOPR 12 months after surgery, SUCRA=79.9) and AGV +IVAV (success rate, SUCRA=92.7). Adverse events were also summarised in detail. CONCLUSION: In the treatment of neovascular glaucoma, AGV+IVAV and CPC were more effective in IOPR and success rate than the other four interventions. Additionally, AGV+IVAV is superior to CPC concerning the success rate in the long-term treatment. However, considering the limitations of this review, more high-quality trials, especially those surgical interventions not mentioned in this review, should be carried out in the future to further confirm the current findings.


Assuntos
Implantes para Drenagem de Glaucoma , Glaucoma Neovascular , Trabeculectomia , Implantes para Drenagem de Glaucoma/efeitos adversos , Glaucoma Neovascular/etiologia , Glaucoma Neovascular/cirurgia , Humanos , Pressão Intraocular , Metanálise em Rede , Resultado do Tratamento
11.
Adv Mater ; 34(15): e2108992, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34981867

RESUMO

Implantable meshes used in tension-free repair operations facilitate treatment of internal soft-tissue defects. However, clinical meshes fail to achieve anti-deformation, anti-adhesion, and pro-healing properties simultaneously, leading to undesirable surgery outcomes. Herein, inspired by the peritoneum, a novel biocompatible Janus porous poly(vinyl alcohol) hydrogel (JPVA hydrogel) is developed to achieve efficient repair of internal soft-tissue defects by a facile yet efficient strategy based on top-down solvent exchange. The densely porous and smooth bottom-surface of JPVA hydrogel minimizes adhesion of fibroblasts and does not trigger any visceral adhesion, and its loose extracellular-matrix-like porous and rough top-surface can significantly improve fibroblast adhesion and tissue growth, leading to superior abdominal wall defect treatment to commercially available PP and PCO meshes. With unique anti-swelling property (maximum swelling ratio: 6.4%), JPVA hydrogel has long-lasting anti-deformation performance and maintains high mechanical strength after immersion in phosphate-buffered saline (PBS) for 14 days, enabling tolerance to the maximum abdominal pressure in an internal wet environment. By integrating visceral anti-adhesion and defect pro-healing with anti-deformation, the JPVA hydrogel patch shows great prospects for efficient internal soft-tissue defect repair.


Assuntos
Parede Abdominal , Peritônio , Parede Abdominal/cirurgia , Materiais Biocompatíveis/farmacologia , Humanos , Hidrogéis , Porosidade , Aderências Teciduais
12.
Adv Sci (Weinh) ; 8(8): 2003627, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33898178

RESUMO

Treatment of wounds in special areas is challenging due to inevitable movements and difficult fixation. Common cotton gauze suffers from incomplete joint surface coverage, confinement of joint movement, lack of antibacterial function, and frequent replacements. Hydrogels have been considered as good candidates for wound dressing because of their good flexibility and biocompatibility. Nevertheless, the adhesive, mechanical, and antibacterial properties of conventional hydrogels are not satisfactory. Herein, cationic polyelectrolyte brushes grafted from bacterial cellulose (BC) nanofibers are introduced into polydopamine/polyacrylamide hydrogels. The 1D polymer brushes have rigid BC backbones to enhance mechanical property of hydrogels, realizing high tensile strength (21-51 kPa), large tensile strain (899-1047%), and ideal compressive property. Positively charged quaternary ammonium groups of tethered polymer brushes provide long-lasting antibacterial property to hydrogels and promote crawling and proliferation of negatively charged epidermis cells. Moreover, the hydrogels are rich in catechol groups and capable of adhering to various surfaces, meeting adhesive demand of large movement for special areas. With the above merits, the hydrogels demonstrate less inflammatory response and faster healing speed for in vivo wound healing on rats. Therefore, the multifunctional hydrogels show stable covering, little displacement, long-lasting antibacteria, and fast wound healing, demonstrating promise in wound dressing.


Assuntos
Antibacterianos/farmacologia , Curativos Hidrocoloides , Materiais Biocompatíveis/uso terapêutico , Hidrogéis/uso terapêutico , Adesividade , Animais , Modelos Animais de Doenças , Ratos , Resistência à Tração , Cicatrização
13.
Fitoterapia ; 97: 15-22, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24862065

RESUMO

One megastigmane derivative 1, one methyl jasmonate glycoside derivative 2, and two C-28 steroids with 3ß,5ß-cis-dihydroxyl conformation 3 and 4, together with eight known compounds 5-12 were isolated from the 70% ethanol extract of linseed meal (Linum usitatissimum L). Structures of 1-4 were elucidated by spectroscopic methods including NMR, HRESIMS, and Mo2(OAc)4-induced CD. The absolute configuration of 1 and 3 was determined by observing their induced circular dichroism after addition of Mo2(OAc)4 in DMSO. The absolute configuration of 2 was determined by NOESY experiment together with conformational analysis. The structure of 4a was corrected as 4 by an extensive analysis of its 1D and 2D NMR, in combination with the Mo2(OAc)4-induced CD in DMSO. The effect of all the isolates on nitric oxide (NO) generation by stimulated macrophages was evaluated, and none of them showed active.


Assuntos
Linho/química , Acetatos/química , Cicloexanonas/química , Ciclopentanos/química , Glucosídeos/química , Glicosídeos/química , Estrutura Molecular , Norisoprenoides/química , Oxilipinas/química , Fitosteróis/química , Fitosteróis/isolamento & purificação
14.
Rapid Commun Mass Spectrom ; 28(10): 1164-74, 2014 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-24711279

RESUMO

RATIONALE: Impurity analysis plays an important role to guarantee the quality and safety of pharmaceuticals. However, identification of impurities remains challenging, especially for those unknown or at trace levels. We present an integrated approach to detect and characterize the trace impurities in drugs. METHODS: Based on liquid chromatography-tandem mass spectrometry (LC-MS/MS), an approach integrating automatic impurity screening method using multiple mass defect filters (MMDFs) and background subtraction (BS) was developed. This approach was used to acquire the structural and semi-quantitative information in a single sample run, and even to discover the impurity signals submerged by background and drug ions. This approach was illustrated by the comprehensive impurity analysis of levofloxacin. RESULTS: This approach was sensitive to detect impurities at the level of 0.02% with respect to levofloxacin concentration. Nineteen impurities were detected, fourteen of which were structurally characterized and eight impurities were reported for the first time. Impurity profiles of levofloxacin drug substances and degradation samples were obtained reliably. A plausible degradation pathway of levofloxacin was proposed including descarboxyl reaction under acid, piperazinyl ring cleavage degradation under light, and N-oxidation under oxidative condition. CONCLUSIONS: The generic approach integrating LC-MS/MS and an automatic impurity screening method was developed for the detection, characterization and monitoring of impurities, especially those unknown or at trace levels. This approach was demonstrated to be rapid, sensitive and automatic for impurity profiling of drugs.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Levofloxacino/análise , Levofloxacino/química , Espectrometria de Massas em Tandem/métodos , Contaminação de Medicamentos , Espectrometria de Massas por Ionização por Electrospray/métodos
15.
J Pharm Biomed Anal ; 90: 92-7, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24333707

RESUMO

Quantitative nuclear magnetic resonance spectroscopy (qNMR) has been developed into an important tool in the drug analysis, biomacromolecule detection, and metabolism study. Compared with mass balance method, qNMR method bears some advantages in the calibration of reference standard (RS): it determines the absolute amount of a sample; other chemical compound and its certified reference material (CRM) can be used as internal standard (IS) to obtain the purity of the sample. Protoberberine alkaloids have many biological activities and have been used as reference standards for the control of many herbal drugs. In present study, the qNMR methods were developed for the calibration of berberine hydrochloride, palmatine hydrochloride, tetrahydropalmatine, and phellodendrine hydrochloride with potassium hydrogen phthalate as IS. Method validation was carried out according to the guidelines for the method validation of Chinese Pharmacopoeia. The results of qNMR were compared with those of mass balance method and the differences between the results of two methods were acceptable based on the analysis of estimated measurement uncertainties. Therefore, qNMR is an effective and reliable analysis method for the calibration of RS and can be used as a good complementarity to the mass balance method.


Assuntos
Alcaloides de Berberina/análise , Medicamentos de Ervas Chinesas/análise , Espectroscopia de Ressonância Magnética/métodos , Alcaloides de Berberina/normas , Calibragem , China , Medicamentos de Ervas Chinesas/normas , Guias como Assunto , Farmacopeias como Assunto , Padrões de Referência , Reprodutibilidade dos Testes
16.
PLoS One ; 8(10): e77969, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24205048

RESUMO

Berberine (BBR) has been confirmed to have multiple bioactivities in clinic, such as cholesterol-lowering, anti-diabetes, cardiovascular protection and anti- inflammation. However, BBR's plasma level is very low; it cannot explain its pharmacological effects in patients. We consider that the in vivo distribution of BBR as well as of its bioactive metabolites might provide part of the explanation for this question. In this study, liquid chromatography coupled to ion trap time-of-flight mass spectrometry (LC/MS(n)-IT-TOF) as well as liquid chromatography that coupled with tandem mass spectrometry (LC-MS/MS) was used for the study of tissue distribution and pharmacokinetics of BBR in rats after oral administration (200 mg/kg). The results indicated that BBR was quickly distributed in the liver, kidneys, muscle, lungs, brain, heart, pancreas and fat in a descending order of its amount. The pharmacokinetic profile indicated that BBR's level in most of studied tissues was higher (or much higher) than that in plasma 4 h after administration. BBR remained relatively stable in the tissues like liver, heart, brain, muscle, pancreas etc. Organ distribution of BBR's metabolites was also investigated paralleled with that of BBR. Thalifendine (M1), berberrubine (M2) and jatrorrhizine (M4), which the metabolites with moderate bioactivity, were easily detected in organs like the liver and kidney. For instance, M1, M2 and M4 were the major metabolites in the liver, among which the percentage of M2 was up to 65.1%; the level of AUC (0-t) (area under the concentration-time curve) for BBR or the metabolites in the liver was 10-fold or 30-fold higher than that in plasma, respectively. In summary, the organ concentration of BBR (as well as its bioactive metabolites) was higher than its concentration in the blood after oral administration. It might explain BBR's pharmacological effects on human diseases in clinic.


Assuntos
Berberina/análogos & derivados , Administração Oral , Animais , Área Sob a Curva , Berberina/administração & dosagem , Berberina/sangue , Berberina/farmacocinética , Cromatografia Líquida , Humanos , Masculino , Ratos , Ratos Sprague-Dawley , Espectrometria de Massas em Tandem , Distribuição Tecidual
17.
J Pharm Sci ; 102(11): 4181-92, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24006193

RESUMO

Berberine (BBR) has been confirmed to show extensive bioactivities for the treatments of diabetes and hypercholesterolemia in clinic. However, there are few pharmacokinetic studies to elucidate the excretions of BBR and its metabolites. Our research studied the excretions of BBR and its metabolites in rats after oral administration (200 mg/kg). Metabolites in bile, urine, and feces were detected by liquid chromatography coupled to ion trap time-of-flight mass spectrometry; meanwhile, a validated liquid chromatography coupled with tandem mass spectrometry method was developed for their quantifications. Sixteen metabolites, including 10 Phase I and six Phase II metabolites were identified and clarified after dosing in vivo. Total recovered rate of BBR was 22.83% (19.07% of prototype and 3.76% of its metabolites) with 9.2 × 10(-6) % in bile (24 h), 0.0939% in urine (48 h), and 22.74% in feces (48 h), respectively. 83% of BBR was excreted as thalifendine (M1) from bile, whereas thalifendine (M1) and berberrubine (M2) were the major metabolites occupying 78% of urine excretion. Most of BBR and its metabolites were found in feces containing 84% of prototype. In summary, we provided excretion profiles of BBR and its metabolites after oral administration in rats in vivo.


Assuntos
Berberina/análogos & derivados , Administração Oral , Animais , Berberina/análise , Berberina/metabolismo , Berberina/urina , Bile/química , Bile/metabolismo , Cromatografia Líquida de Alta Pressão/métodos , Fezes/química , Masculino , Ratos , Ratos Sprague-Dawley , Espectrometria de Massas em Tandem/métodos
18.
Wei Sheng Wu Xue Bao ; 53(5): 455-63, 2013 May 04.
Artigo em Chinês | MEDLINE | ID: mdl-23957149

RESUMO

OBJECTIVE: We screened a bacterial strain capable of degrading chlorobenzene, and purified the corresponding degradation enzyme. METHODS: The strain was screened by gradient enrichment culture and sterile filter paper plate method, and identified by morphology and 16S rRNA gene sequence. Chlorobenzene concentration in the liquid culture was determined by gas chromatography. Degradation capability was assayed by the proportion of chlorobenzene degraded per cells. The purity quotient and molecular weight of the purified degradation enzyme were determined by gel per cell. electrophoresis. RESULTS: The isolated bacterium, LW13, used chlorobenzene in activated sludge as sole carbon and energy source. Cells were 2.3 microm long and 0.8 microm wide, with several terminal flagella. Strain LW13 was 95.5% similar to Lysinibacillus fusiformis, and its degradation enzyme was a positively-charged exoenzyme (molecular weight about 57 kDa). The optimal temperature and pH of the purified enzyme were approximately 40 degrees C and 8.0, respectively. CONCLUSION: Strain LW13 belongs to genus Lysinibacillus, and can degrade chlorobenzene (500-2000 mg/L).


Assuntos
Bactérias/enzimologia , Clorobenzenos/metabolismo , Enzimas/isolamento & purificação , Bactérias/classificação , Bactérias/genética , Biodegradação Ambiental , Ativação Enzimática , Concentração de Íons de Hidrogênio , Filogenia , RNA Ribossômico 16S , Temperatura
19.
Anal Chim Acta ; 731: 60-7, 2012 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-22652265

RESUMO

An integrated approach combining data acquisition using MS(E) and multi-period product ion scan (mpMS/MS), with high-resolution characteristic extracted ion chromatograms (hcXIC) as a data mining method, was developed for in vivo drug metabolites screening and identification. This approach is illustrated by analyzing metabolites of a potential anticancer agent, 3,6,7-trimethoxyphenanthroindolizidine (CAT) in rat urine based on rapid resolution liquid chromatography combined with tandem mass spectrometry (RRLC-MS/MS). Untargeted full-scan MS(E) enabled the high-throughput acquisition of potential metabolites, and targeted mpMS/MS contributed to the sensitivity and specificity of the acquisition of molecules of interest. The data processing method hcXIC, based on the structure of CAT, was shown to be highly effective for the metabolite discovery. Through the double-filtering effect of the characteristic ion and accurate mass, conventional extracted ion chromatograms that contained a substantial number of false-positive peaks were simplified into chromatograms essentially free of endogenous interferences. As a result, 21 metabolites were detected in rat urine after oral administration of CAT. Based on the characteristic fragmentation patterns of the phenanthroindolizidine alkaloid, the structures of 9 metabolites were identified. Furthermore, the interpretation of the MS/MS spectra of these metabolites enabled the determination of demethylation position as well as the differentiation between N-oxidized and hydroxylated metabolites.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Indolizidinas/metabolismo , Indolizidinas/urina , Fenantrenos/metabolismo , Fenantrenos/urina , Integração de Sistemas , Espectrometria de Massas em Tandem/métodos , Urinálise/métodos , Animais , Antineoplásicos/metabolismo , Antineoplásicos/urina , Mineração de Dados , Espectroscopia de Ressonância Magnética , Masculino , Ratos , Ratos Wistar , Fatores de Tempo
20.
Int J Mol Sci ; 12(4): 2556-71, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21731458

RESUMO

Nuclear magnetic resonance/liquid chromatography-mass spectroscopy parallel dynamic spectroscopy (NMR/LC-MS PDS) is a method aimed at the simultaneous structural identification of natural products in complex mixtures. In this study, the method is illustrated with respect to (1)H NMR and rapid resolution liquid chromatography-mass spectroscopy (RRLC-MS) data, acquired from the crude extract of Anoectochilus roxburghii, which was separated into a series of fractions with the concentration of constituent dynamic variation using reversed-phase preparative chromatography. Through fraction ranges and intensity changing profiles in (1)H NMR/RRLC-MS PDS spectrum, (1)H NMR and the extracted ion chromatogram (XIC) signals deriving from the same individual constituent, were correlated due to the signal amplitude co-variation resulting from the concentration variation of constituents in a series of incompletely separated fractions. 1H NMR/RRLC-MS PDS was then successfully used to identify three types of natural products, including eight flavonoids, four organic acids and p-hydroxybenzaldehyde, five of which have not previously been reported in Anoectochilus roxburghii. In addition, two groups of co-eluted compounds were successfully identified. The results prove that this approach should be of benefit in the unequivocal structural determination of a variety of classes of compounds from extremely complex mixtures, such as herbs and biological samples, which will lead to improved efficiency in the identification of new potential lead compounds.


Assuntos
Produtos Biológicos/química , Orchidaceae/química , Extratos Vegetais/química , Produtos Biológicos/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Orchidaceae/metabolismo , Extratos Vegetais/isolamento & purificação
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