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1.
Neurosci Bull ; 2020 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-31989424

RESUMO

Chemical stimulation of the kidney increases sympathetic activity and blood pressure in rats. The hypothalamic paraventricular nucleus (PVN) is important in mediating the excitatory renal reflex (ERR). In this study, we examined the role of molecular signaling in the PVN in mediating the capsaicin-induced ERR and sympathetic activation. Bilateral PVN microinjections were performed in rats under anesthesia. The ERR was elicited by infusion of capsaicin into the cortico-medullary border of the right kidney. The reflex was evaluated as the capsaicin-induced changes in left renal sympathetic nerve activity and mean arterial pressure. Blockade of angiotensin type 1 receptors with losartan or inhibition of angiotensin-converting enzyme with captopril in the PVN abolished the capsaicin-induced ERR. Renal infusion of capsaicin significantly increased NAD(P)H oxidase activity and superoxide anion production in the PVN, which were prevented by ipsilateral renal denervation or microinjection of losartan into the PVN. Furthermore, either scavenging of superoxide anions or inhibition of NAD(P)H oxidase in the PVN abolished the capsaicin-induced ERR. We conclude that the ERR induced by renal infusion of capsaicin is mediated by angiotensin type 1 receptor-related NAD(P)H oxidase activation and superoxide anion production within the PVN.

2.
Food Chem ; 303: 125391, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31466030

RESUMO

Sunflower oil-in-water Pickering emulsions were fabricated using octenyl succinic anhydride (OSA) modified starch particles and small molecular surfactants (e.g., SDS, CTAB and Tween 20) as stabilizers. Emulsions were characterized for physical stabilities by cream volume, droplet size distribution and microstructure. Oxidative stabilities of the emulsions were investigated by accelerated oxidation tests at 50 °C. Results showed that cream volumes had little difference after 14 days of storage, while the droplet sizes of emulsions stabilized by starch particles and surfactants decreased greatly compared to those only with starch particles (p < 0.05). Droplet microstructure revealed that small molecular surfactants competed with starch particles for the adsorption at interface. The emulsion stabilized by 1.0% OS-starch particle and 1.0% SDS had the lowest peroxide value and acid value. These findings implied that starch particles were compatible with anionic surfactants and could enhance the stabilities and decrease the oxidation rate of Pickering emulsions.


Assuntos
Emulsões/química , Amido/análogos & derivados , Oxirredução , Amido/química , Óleo de Girassol/química , Tensoativos/química , Água/química
3.
Spectrochim Acta A Mol Biomol Spectrosc ; 229: 117944, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31855815

RESUMO

A facile, economical and one-step hydrothermal method was used to synthesize fluorescent carbon dots by utilizing citric acid as carbon source and phenylalanine to provide nitrogen. The as-prepared fluorescence carbon dots had strong blue light emission around 440 nm. As confirmed by UVvis absorption, X-ray photoelectron spectroscopic, Fourier transform infrared spectroscopy and transmission electron microscope characterization, the carbon dots were small and very stable in water for using as a fluorescent probe. It was also found that the fluorescence of the carbon dots could be quenched in the presence of Fe3+ ions, and the quenching rate was linear with the concentration of Fe3+ ions. We here proposed a static quenching mechanism about the fluorescence of the Phe-CDs could be selectively quenched by Fe3+ ions, which was because these Fe3+ ions could easily combine with the hydroxyl or carboxyl groups on the surface of Phe-CDs and induced aggregation. In addition, the pH had little effect on the fluorescence intensity of the Phe-CDs and maintained excellent fluorescence intensity even under extreme pH value conditions and could be used for the detection of Fe3+ ions. We have demonstrated that the method using the carbon dots for Fe3+ ions detection was rapid, reliable, and selective with a detection limit as low as 0.720 µM and a dynamic range from 5.0 to 500.0 µM. Moreover, the results of determination Fe3+ ions in tap water samples indicated that the presented method has potential for practical application in environmental metal analysis.

4.
Adv Healthc Mater ; 8(24): e1901301, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31763779

RESUMO

Due to their excellent size, designability, and outstanding targeted antibacterial effects, nanoparticles have become a potential option for controlling oral biofilm-related infections. However, the formation of an oral biofilm is a dynamic process, and factors affecting the performance of antibiofilm treatments are complex. As such, when examining the existing literature on the antibiofilm effects of nanoparticles, attention should be paid to the specific mechanisms of action at different stages of oral biofilm formation, as well as relevant influencing factors, in order to achieve an objective and comprehensive evaluation. This review is intended to detail the antibacterial mechanisms of nanoparticles during the four stages of the formation of oral biofilms: 1) acquired film formation; 2) bacterial adhesion; 3) early biofilm development; and 4) biofilm maturation. In addition, factors influencing the antibiofilm properties of nanoparticles are summarized from the aspects of nanoparticles themselves, biofilm models, and host factors. The limitations of current research and possible trends for future research are also discussed. In summary, nanoparticles are a promising antioral biofilm strategy. It is hoped that this review can serve as a reference and inspire ideas for further research on the application of nanoparticles for effectively targeting and treating oral biofilms.

5.
World J Clin Cases ; 7(10): 1177-1183, 2019 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-31183350

RESUMO

BACKGROUND: Small cell lung cancer (SCLC) accounts for 15% of lung cancers, and it commonly expresses peptide and protein factors that are active as hormones. These secreting factors manifest as paraneoplastic disorders, such as ectopic adrenocorticotropic hormone (ACTH) syndrome (EAS). The clinical features are abnormalities in carbohydrate metabolism, hypokalemia, peripheral edema, proximal myopathy, hypertension, hyperpigmentation, and severe systemic infection. However, it is uncommon that EAS has an influence on hypothalamus-pituitary function. CASE SUMMARY: A 62-year-old man presented with complaints of haemoptysis, polyuria, polydipsia, increased appetite, weight loss, and pigmentation. Following a series of laboratory and imaging examinations, he was diagnosed with SCLC, EAS, hypogonadism, hypothyroidism, and central diabetes insipidus. After three rounds of chemotherapy, levels of ACTH, cortisol, thyroid hormone, gonadal hormone, and urine volume had returned to normal levels. In addition, the pulmonary tumor was reduced in size. CONCLUSION: We report a rare case of SCLC complicated with panhypopituitarism due to EAS. We hypothesize that EAS induced high levels of serum glucocorticoid and negative feedback for the synthesis and secretion of antidiuretic hormone from the paraventricular nucleus, and trophic hormones from the anterior pituitary. Therefore, patients who present with symptoms of hypopituitarism, or even panhypopituitarism, with SCLC should be evaluated for EAS.

6.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 36(6): 628-631, 2019 Jun 10.
Artigo em Chinês | MEDLINE | ID: mdl-31055823

RESUMO

OBJECTIVE: To analyze the genotype and phenotype of a sibpair with partial deletion of SATB2 gene caused by 2q33.1 microdeletion. METHODS: Both children have featured mental retardation and development delay, and were subjected to karyotyping, single nucleotide microarray (SNP array) and real-time fluorescence quantitative PCR analysis. Karyotyping and SNP Array analysis were also carried out on their parents to verify the origin of mutation. RESULTS: Both sibs had a normal karyotype. SNP array showed that sib 1 had arr[hg19]2q33.1(200 192 328 - 200 197 269)×1 (4.9 kb), 2q35 (218 105 663 - 218 816 675)×3 (711 kb), while sib 2 had arr[hg19]2q33.1(200 192 328 - 200 197 269)×1 (4.9 kb), 2q35 (218 105 663-218 810 908)×3 (705.2 kb). The deletion has partially overlapped with that of 2q33.1 microdeletion syndrome and involved part of the SATB2 gene. The result of real-time fluorescence quantitative PCR assay was consistent with that of SNP assay. The duplication has originated from their father and has not been associated with any disease phenotypen. CONCLUSION: Both sibs have carried partial deletion of SATB2 gene and had similar clinical phenotypes. Haploinsufficiency of such gene probably underlies the clinical manifestations in both patients.


Assuntos
Transtornos Cromossômicos , Proteínas de Ligação à Região de Interação com a Matriz/genética , Fatores de Transcrição/genética , Criança , Deleção Cromossômica , Cromossomos Humanos Par 2 , Testes Genéticos , Humanos , Cariotipagem , Fenótipo
7.
Zhongguo Zhong Yao Za Zhi ; 43(1): 31-38, 2018 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-29552808

RESUMO

The pharmacological activity of active ingredients from Chinese medicine depends greatly on the microecological environment of probiotics in the human body. After effective ingredients from traditional Chinese medicines are metabolized or biotransformed by probiotics, their metabolites can increase pharmacological activity, and can be absorbed more easily to improve the bioavailability. Therefore, the combination of Chinese medicines with probiotics is the innovation point in R&D of functional food and Chinese medicines, and also a new thinking for the modernization of Chinese medicine.This review summarizes and analyses the research progress on metabolism effects of gut microbiota on Chinese medicines components, the regulating effect of effective ingredients from Chinese medicine on intestinal probiotics, the application status of probiotics in traditional Chinese medicines, and the main problems and prospects in the research and development of Chinese medicines products with probiotic, aiming to provide theoretical guidance and practical value for the fermentation engineering of Chinese herbal medicine.


Assuntos
Medicamentos de Ervas Chinesas/metabolismo , Probióticos , Humanos , Medicina Tradicional Chinesa
8.
J Inequal Appl ; 2018(1): 278, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30839771

RESUMO

In this paper, a filter QP-free infeasible method with nonmonotone line search is proposed for minimizing a smooth optimization problem with smooth inequality constraints. This proposed method is based on the solution of nonsmooth equations, which are obtained by the Lagrangian multiplier method and the function of the nonlinear complementarity problem for the Karush-Kuhn-Tucker optimality conditions. Especially, each iteration of this method can be viewed as a perturbation of a Newton or quasi-Newton iteration on both the primal and dual variables for the solution of the Karush-Kuhn-Tucker optimality conditions. What is more, it is considered to use the function of the nonlinear complementarity problem in the filter, which makes the proposed algorithm avoid the incompatibility. Then the global convergence of the proposed method is given. And under some mild conditions, the superlinear convergence rate can be obtained. Finally, some preliminary numerical results are shown to illustrate that the proposed filter QP-free infeasible method is quite promising.

9.
Bioorg Med Chem Lett ; 27(8): 1808-1814, 2017 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-28274630

RESUMO

The synthesis of a series of novel 4-substituted 2,3,6,7-tetrahydrobenzo [1,2-b;4,5-b']difuran-1H-imidazolium salts is presented. The biological properties of the compounds were evaluated in vitro against a panel of human tumor cell lines. Results suggest that the 5,6-dimethyl-benzimidazole or 2-methyl-benzimidazole ring, and substitution of the imidazolyl-3-position with a 2-naphthylmethyl substituent or 2-naphthylacyl substituent, were important to the cytotoxic activity. Notably, 3-(2-Naphthylmethyl)-1-((2,3,6,7-tetrahydrobenzo[1,2-b;4,5-b']difuran-4-yl)methyl)-1H-5,6-dimethyl-benzimidazol-3-ium bromide (42) was found to be the most potent derivative against five human tumor cell lines with IC50 values of 1.06-4.34µM and more selective towards SMMC-7721, A549 and SW480 cell lines. 3-(2-Naphthylacyl)-1-((2,3,6,7-tetrahydrobenzo[1,2-b;4,5-b']difuran-4-yl)methyl)-1H-2-methyl-benzimidazol-3-ium bromide (37) showed higher selectivity to SMMC-7721 and MCF-7 cell lines with IC50 values 2.7-fold and 8.4-fold lower than DDP. Study regarding to the antitumor mechanism of action showed that compound 37 could induce cell cycle G1 phase arrest and apoptosis in SMMC-7721 cells.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Benzofuranos/química , Benzofuranos/farmacologia , Imidazóis/química , Imidazóis/farmacologia , Antineoplásicos/síntese química , Apoptose/efeitos dos fármacos , Benzimidazóis/síntese química , Benzimidazóis/química , Benzimidazóis/farmacologia , Benzofuranos/síntese química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Imidazóis/síntese química , Modelos Moleculares , Relação Estrutura-Atividade
10.
Org Biomol Chem ; 14(39): 9423-9430, 2016 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-27714171

RESUMO

The synthesis of a series of novel N-substituted tetrahydro-ß-carboline-imidazolium salt derivatives is presented. The biological properties of the compounds were evaluated in vitro against a panel of human tumor cell lines. The results suggest that the benzimidazole ring and 1-(naphthalen-2-yl)ethan-1-one or 2-naphthylmethyl substituent at the imidazolyl-3-position were vital for modulating cytotoxic activity. Compound 41 was observed as a potent derivative with IC50 values of 3.24-8.78 µM and exhibited cytotoxic activity selectively against HL-60, A-549 and MCF-7 cell lines. Meanwhile, high inhibitory activities selectively against HL-60 and MCF-7 cell lines were observed for compound 51. Moreover, compound 51 was able to induce G1 phase cell cycle arrest and apoptosis in MCF-7 cells. The cytotoxicity of compound 51 against human normal lung epithelial cell line BEAS-2B was further evaluated.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Imidazóis/síntese química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Benzimidazóis/química , Carbolinas/química , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais/métodos , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Células HL-60 , Humanos , Células MCF-7 , Relação Estrutura-Atividade
11.
BMC Microbiol ; 16: 71, 2016 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-27103443

RESUMO

BACKGROUND: The connection structure of class 1 integron and insertion sequence common region 1 (ISCR1) is called "complex class 1 integrons" or "complex sul1-type integrons", which is also known to be associated with many resistance genes. This structure is a powerful gene-capturing tool kit that can mobilize antibiotic resistance genes. In order to look for and study the structure among clinical multidrug-resistant (MDR) Gram-negative isolates, 63 isolates simultaneously harbored class 1 integron and ISCR1-linked resistance genes were isolated from 2309 clinical non-redundant MDR Gram-negative isolates in Nanfang Hospital in 2008-2013. The connecting regions between the class 1 integrons and ISCR1 were examined using PCR and DNA sequencing to determine the structures in these isolates. RESULT: The two elements (the variable regions of the class 1 integron structures and the ISCR1-linked resistance genes) are connected in series among 63 isolates according to long-extension PCR and DNA sequencing. According to the kinds and permutations of resistance genes in the structure, 12 distinct types were identified, including 8 types that have never been described in any species. Several types of these structures are similar with the structures of other reports, but not entirely same. CONCLUSION: This study is the first to determine the structure simultaneously harboring class 1 integron and ISCR1-linked resistance genes by detecting the region connecting class 1 integrons and ISCR1 in a large number of MDR bacteria. These structures carrying various resistance genes were closely associated with multidrug resistance bacteria in Southern China.


Assuntos
Farmacorresistência Bacteriana Múltipla , Bactérias Gram-Negativas/isolamento & purificação , Integrons , Análise de Sequência de DNA/métodos , Proteínas de Bactérias/genética , DNA Bacteriano/genética , Bactérias Gram-Negativas/genética , Infecções por Bactérias Gram-Negativas/microbiologia , Humanos , Reação em Cadeia da Polimerase
12.
Chin J Integr Med ; 22(8): 611-8, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25847779

RESUMO

OBJECTIVE: To investigate the effect of Xuezhikang (, XZK) on renal cell apoptosis in diabetic rats and the possible mechanism. METHODS: Sixty-six rats were randomly divided into 3 groups: the normal, model and XZK groups. In each group, the rats were further randomly divided into 3-month and 6-month subgroups, respectively. Diabetes of rats was induced by a single intraperitoneal injection of 1% streptozocin at 60 mg/kg body weight. Rats in the XZK group received gastric perfusion of XZK (1200 mg/kg body weight) everyday for 3 or 6 months, while rats in the normal and model groups received equal volume of saline. Twenty-four hours' urine was collected for urinary albumin excretion (UAE) measurement. Periodic acid-Schiff (PAS) and Masson's trichrome staining were used for saccharides and collagen detection. Cell apoptosis of renal cortex was investigated by TdT-mediated dUTP nick end labeling (TUNEL) staining. Bax and Bcl-2 expressions were detected by immunohistochemistry and Western blot, respectively. Cytochrome C (Cyt C) and caspase-9 concentration were detected by Western blot. RESULTS: Compared with the model group, XZK treatment could significantly decrease the kidney hypertrophy index, 24 h UAE, renal cell apoptosis, cytoplasmic Cyt C level and active caspase-9 level, as well as suppress the increment of Bax and up-regulate the expression of Bcl-2, leading to the suppression of Bax/Bcl-2 ratio at 3 and 6 months (P<0.05 or P<0.01). Moreover, XZK treatment could alleviate the deposition of PAS-stained saccharides and Masson's trichromestained collagen to different extent. CONCLUSIONS: Renal cell apoptosis was observed in diabetic kidney, in which mitochondrial apoptotic pathway might be involved. XZK treatment could attenuate pathological changes in diabetic kidney and reduce renal cell apoptosis, probably via the suppression of Bax/Bcl-2 ratio, which lead to inhibition of Cyt C release and following caspase-9 activation.


Assuntos
Apoptose , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/patologia , Medicamentos de Ervas Chinesas/uso terapêutico , Rim/patologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Albuminúria/sangue , Albuminúria/complicações , Animais , Apoptose/efeitos dos fármacos , Glicemia/metabolismo , Caspase 9/metabolismo , Citocromos c/metabolismo , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Hipertrofia , Marcação In Situ das Extremidades Cortadas , Rim/efeitos dos fármacos , Glomérulos Renais/patologia , Lipídeos/sangue , Masculino , Células Mesangiais/efeitos dos fármacos , Células Mesangiais/patologia , Ratos Sprague-Dawley , Estreptozocina , Proteína X Associada a bcl-2/metabolismo
13.
Anal Chem ; 87(23): 11739-45, 2015 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-26524192

RESUMO

Great challenges in investigating the release of drug in complex cellular microenvironments necessitate the development of stimuli-responsive drug delivery systems with real-time monitoring capability. In this work, a smart drug nanocarrier based on fluorescence resonance energy transfer (FRET) is fabricated by capping graphene quantum dots (GQDs, the acceptor) onto fluorescent mesoporous silica nanoparticles (FMSNs, the donor) via ATP aptamer for real-time monitoring of ATP-triggered drug release. Under extracellular conditions, the fluorescence of FMSNs remains in the "off" state in the low ATP level which is unable to trigger the release of drug. Once specifically recognized and internalized into the target tumor cells by AS1411 aptamer, in the ATP-rich cytoplasm, the conformation switch of the ATP aptamer causes the shedding of the GQDs from the nanocarriers, leading to the release of the loaded drugs and consequently severe cytotoxicity. Simultaneously, the fluorescence of FMSNs turns "on" along with the dissociation of GQDs, which allows real-time monitoring of the release of drug from the pores. Such a drug delivery system features high specificity of dual-target recognition with AS1411 and ATP aptamer as well as high sensitivity of the FRET-based monitoring strategy. Thus, the proposed multifunctional ATP triggered FRET-nanocarriers will find potential applications for versatile drug-release monitoring, efficient drug transport, and targeted cancer therapeutics.


Assuntos
Antineoplásicos/química , Aptâmeros de Nucleotídeos/química , Doxorrubicina/química , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Grafite/química , Pontos Quânticos , Dióxido de Silício/química , Trifosfato de Adenosina/química , Animais , Antineoplásicos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Doxorrubicina/farmacologia , Fluorescência , Células HeLa , Humanos , Camundongos , Células NIH 3T3 , Porosidade , Relação Estrutura-Atividade , Fatores de Tempo , Células Tumorais Cultivadas
14.
Eur J Cardiothorac Surg ; 48(3): 375-81, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25715432

RESUMO

OBJECTIVES: The loss of effectiveness of ischaemic preconditioning in protecting old hearts from ischaemia/reperfusion damage is thought to be due to low sirtuin 1 levels in old hearts. We sought to determine whether resveratrol (RES), an activator of sirtuin 1, would restore this protection to that seen with ischaemic preconditioning in young hearts. METHODS: A Langendorff heart perfusion model was established in 80 old and 80 adult rats to test the effects of hypoxic preconditioning (HPC) and/or RES on preventing hypoxia-reperfusion (H/R) injury. The effects were further tested by comparing the effects of HPC and RES on cell survival rate and lactate dehydrogenase (LDH) in cardiomyocytes from 15 old and 15 young humans. RESULTS: The HPC + RES group performed better in both adult and old groups than the corresponding H/R, HPC and RES groups, causing ∼50% in the adult and 40% in the old group restoration of left ventricular developed pressure and ∼90% in the adult and 80% in the old group restoration of dp/dtmax. HPC and RES each reduced apoptosis in both groups. The HPC + RES treatment showed an additive benefit in reducing apoptosis in the adult group but not in the old group. In H/R-treated young and old human cardiomyocytes, cell survival and LDH level were significantly improved in the RES + HPC group compared with the HPC group. CONCLUSIONS: This study showed that RES lessened the ageing effect and enhanced the cardioprotective effect of HPC in older individuals.


Assuntos
Cardiotônicos/uso terapêutico , Precondicionamento Isquêmico Miocárdico/métodos , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Miócitos Cardíacos/efeitos dos fármacos , Estilbenos/uso terapêutico , Fatores Etários , Animais , Células Cultivadas , Frequência Cardíaca/efeitos dos fármacos , Humanos , Masculino , Ratos , Resveratrol , Função Ventricular/efeitos dos fármacos
15.
Microb Drug Resist ; 21(2): 178-85, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25469995

RESUMO

A total of 368 nonreplicate gram-negative bacteria with resistance to imipenem or meropenem were collected to search for carbapenemase genes, class 1 integrons, and insertion sequence with common region 1 (ISCR1). The carbapenemase genes blaIMP-4, blaKPC-2, and blaNDM-1 were found in two Enterobacteriaceae and seven Pseudomonas aeruginosa isolates, nine Klebsiella pneumoniae isolates, and seven Enterobacteriaceae and two Acinetobacter spp. isolates. The class D OXA-type carbapenemase genes blaOXA-23-like, blaOXA-24-like, blaOXA-58, and blaOXA-51-like were detected in 59 (34.9%), 2 (1.2%), 16 (9.5%), and 126 (74.6%) Acinetobacter strains. This is the first description of blaNDM-1 in Enterobacter hormaechei and Acinetobacter genomic species 13TU. Of the integrase-positive strains, 135 (90.0%) Acinetobacter spp., 22 (61.1%) P. aeruginosa, and 14 (100%) Enterobacteriaceae isolates were identified by five, ten, and four different gene cassette arrays, respectively. Three novel gene cassette arrays aadB-aadA1, dfrA25, and dfrA16-aadA2 were reported for the first time in some species. Of the ISCR1-positive strains, the nonfermentative strains (102 Acinetobacter spp. and 13 P. aeruginosa. isolates) contained the same arrangement blaPER-1-putative glutathione-S-transferase-novel type ABC transporter, and three Enterobacteriaceae isolates harbored three different arrangements. Four distinct complex class 1 integron structures were observed. The complex class 1 integron detected in New Delhi, metallo-ß-lactamase (NDM-1)-producing E. hormaechei, was found to coexist in the NDM-1-carrying plasmid. Our results suggested that we should pay more attention to the strict implementation of infection control measures and active antibiotic resistance surveillance to avoid the rapid spread or outbreak of carbapenemase-producing gram-negative bacteria.


Assuntos
Carbapenêmicos/farmacologia , Farmacorresistência Bacteriana/genética , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/genética , Transportadores de Cassetes de Ligação de ATP/genética , Antibacterianos , Proteínas de Bactérias/genética , China , Genes Bacterianos/genética , Glutationa Transferase/genética , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Infecções por Bactérias Gram-Negativas/microbiologia , Humanos , Imipenem/farmacologia , Integrons/genética , Meropeném , Mutagênese Insercional/genética , Tienamicinas/farmacologia , beta-Lactamases/genética
16.
Microb Drug Resist ; 20(6): 533-8, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25000338

RESUMO

A loop-mediated isothermal amplification (LAMP) assay was developed and evaluated for rapid detection of blaKPC, blaNDM, blaIMP, and blaVIM carbapenemase genes. Six oligonucleotides, including outer, inner, and loop primers, were designed for eight distinct regions in each target gene. Two qualitative criteria were used to evaluate LAMP reactions: visual inspection of color change and real-time detection of fluorescence change. The lower detection limit was 10 colony forming units (CFU) per reaction for real-time detection and 100 CFU per reaction for visual inspection for each gene. Two hundred twenty-two carbapenem-resistant clinical isolates (including 100 Pseudomonas aeruginosa, 100 Acinetobacter sp., and 22 Enterobacteriaceae) were tested by LAMP assay. At the same time, these isolates were confirmed by conventional polymerase chain reaction (PCR) and sequencing analysis. In these clinical isolates, the results of 11 strains with blaNDM, 11 strains with blaKPC, 11 strains with blaVIM, and 2 strains with blaIMP obtained using LAMP assays were concordant with conventional PCR. The LAMP method reported here may be a useful and powerful tool for rapid detection of blaNDM, blaKPC, blaIMP, and blaVIM carbapenemase genes in bacteria.


Assuntos
Bactérias/genética , Proteínas de Bactérias/genética , Farmacorresistência Bacteriana/genética , Genes Bacterianos/genética , beta-Lactamases/genética , Técnicas de Amplificação de Ácido Nucleico/métodos , Reação em Cadeia da Polimerase em Tempo Real/métodos
17.
Biomed Environ Sci ; 27(5): 343-52, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24827715

RESUMO

OBJECTIVE: Central obesity is considered to be a central component of metabolic syndrome. Waist circumference (WC) has been widely used as a simple indicator of central obesity. This study is aimed to evaluate the sensitivity of WC cut-off values for predicting metabolic risk factors in middle-aged Chinese. METHODS: The study involved 923 subjects aged 40-65 years. The metabolic risk factors were defined according to the Chinese Joint Committee for Developing Chinese Guidelines on Prevention and Treatment of Dyslipidemia in Adults. WC cut-off 85-90 cm and ⋝90 cm were used as cut-off values of central pre-obesity and central obesity in males, respectively, while WC 80-85 cm and ⋝85 cm were used as cut-off values of central pre-obesity and central obesity in females. RESULTS: First, WC values corresponding to body mass index (BMI) 24 kg/m2 and visceral fat area (VFA) 80 cm2 were 88.55 cm and 88.51 cm in males, and 81.46 cm and 82.51 cm in females respectively. Second, receiver operating characteristic curves showed that the optimal WC cut-off of value was 88.75 cm in males, higher than that in females (81.75 cm). Third, the subjects with higher WC values were more likely to have accumulating metabolic risk factors. The prevalence of metabolic risk factors increased linearly and significantly in relation to WC levels. CONCLUSION: WC cut-off values of central pre-/central obesity are optimal to predict multiple metabolic risk factors.


Assuntos
Síndrome Metabólica/diagnóstico , Obesidade/diagnóstico , Circunferência da Cintura , Idoso , China/epidemiologia , Estudos Transversais , Feminino , Humanos , Gordura Intra-Abdominal/fisiopatologia , Masculino , Síndrome Metabólica/epidemiologia , Síndrome Metabólica/fisiopatologia , Pessoa de Meia-Idade , Curva ROC
18.
Ann Clin Microbiol Antimicrob ; 13: 1, 2014 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-24383440

RESUMO

BACKGROUND: Clinical microbiology laboratories have to accurately identify clinical microbes. However, some isolates are difficult to identify by the automated biochemical text platforms, which are called "difficult-to-identify" microbes in this study. Therefore, the ability of 16S ribosomal DNA (16S rDNA) and internal transcribed spacer 2 (ITS2) sequencing to identify these "difficult-to-identify" bacteria and fungi was assessed in this study. METHODS: Samples obtained from a teaching hospital over the past three years were examined. The 16S rDNA of four standard strains, 18 clinical common isolates, and 47 "difficult-to-identify" clinical bacteria were amplified by PCR and sequenced. The ITS2 of eight standard strains and 31 "difficult-to-identify" clinical fungi were also amplified by PCR and sequenced. The sequences of 16S rDNA and ITS2 were compared to reference data available in GenBank by using the BLASTN program. These microbes were identified according to the percentage of similarity to reference sequences of strains in GenBank. RESULTS: The results from molecular sequencing methods correlated well with automated microbiological identification systems for common clinical isolates. Sequencing results of the standard strains were consistent with their known phenotype. Overall, 47 "difficult-to-identify" clinical bacteria were identified as 35 genera or species by sequence analysis (with 10 of these identified isolates first reported in clinical specimens in China and two first identified in the international literature). 31 "difficult-to-identify" clinical fungi tested could be identified as 15 genera or species by sequence analysis (with two of these first reported in China). CONCLUSIONS: Our results show the importance of 16S rDNA and internal ITS2 sequencing for the molecular identification of "difficult-to-identify" bacteria and fungi. The development of this method with advantages of convenience, availability, and cost-effectiveness will make it worth extending into clinical practice in developing countries.


Assuntos
Bactérias/isolamento & purificação , DNA Espaçador Ribossômico/genética , Fungos/isolamento & purificação , Técnicas Microbiológicas/métodos , Técnicas de Diagnóstico Molecular/métodos , RNA Ribossômico 16S/genética , Bactérias/classificação , Bactérias/genética , Infecções Bacterianas/diagnóstico , China , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Fúngico/química , DNA Fúngico/genética , DNA Espaçador Ribossômico/química , Fungos/classificação , Fungos/genética , Hospitais de Ensino , Humanos , Micoses/diagnóstico , Reação em Cadeia da Polimerase , RNA Ribossômico 16S/química , Análise de Sequência de DNA
19.
Ann Clin Microbiol Antimicrob ; 12: 30, 2013 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-24143953

RESUMO

The latest threat of multidrug-resistant Gram-negative bacteria corresponds to the emergence of carbapenemase New Delhi metallo-ß-lactamase (NDM) and Klebsiella pneumoniae carbapenemase (KPC) producers. Rapid molecular detection is essential to limit their spread. In this study, a duplex real-time polymerase chain reaction (PCR) that was specific for the detection of blaNDM and blaKPC with the same limit of detection of ten plasmid copies was developed. The assay was linear over eight log dilutions for blaNDM (R2 = 0.971; slope, -3.273) and blaKPC (R2 = 0.992; slope, -2.997) with efficiencies of 102% and 115%, respectively. The assay was validated with 157 clinical isolates and showed 100% concordance with conventional PCR. The excellent performance of the duplex PCR assay makes it a powerful tool for surveillance of the carbapenemases NDM and KPC.


Assuntos
Bactérias Gram-Negativas/enzimologia , Bactérias Gram-Negativas/genética , Reação em Cadeia da Polimerase Multiplex/métodos , Reação em Cadeia da Polimerase em Tempo Real/métodos , beta-Lactamases/genética , DNA Bacteriano/química , DNA Bacteriano/genética , Bactérias Gram-Negativas/isolamento & purificação , Infecções por Bactérias Gram-Negativas/microbiologia , Humanos , Dados de Sequência Molecular , Análise de Sequência de DNA
20.
Zhong Yao Cai ; 36(2): 223-5, 2013 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-23901646

RESUMO

OBJECTIVE: To study the chemical constituents in the fruit of Harrisonia perforata. METHODS: The chemical constituents were isolated and purified by means of chromatographic techniques and their structures were elucidated by analysis of spectroscopic data and physicochemical properties. RESULTS: Eight compounds were isolated and identified as caryolane-1,9beta-diol (1), gallic acid (2), 4-O-ethylgallic acid (3), syringic acid ethyl ester (4), protocatechuic acid (5), stigmasterol (6), beta-daucoster (7), beta-sitosterol (8). CONCLUSION: Compounds 1, 3 - 5 and 7 are isolated from this plant for the first time. Compounds 1, 3 and 4 are isolated from this genus for the first time.


Assuntos
Frutas/química , Ácido Gálico/análogos & derivados , Hidroxibenzoatos/química , Simaroubaceae/química , beta Caroteno/química , Cromatografia em Camada Delgada , Ácido Gálico/química , Ácido Gálico/isolamento & purificação , Hidroxibenzoatos/isolamento & purificação , Estrutura Molecular , beta Caroteno/isolamento & purificação
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