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Nanoscale Res Lett ; 14(1): 248, 2019 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-31342195


Herein, a magnetic graphene field-effect transistor biosensor was prepared through the transfer of a chemical vapor deposition graphene film onto a glass substrate to produce a sensing film and conductive channel. By fixing 1-pyrenebutanoic acid succinimidyl ester onto graphene film as an anchor, a probe aptamer was immobilized on the graphene film in order to capture magnetically labeled complementary single-stranded DNA. Our experiments showed that, within a periodic magnetic field, the biosensor impedance exhibited a periodic oscillation, the amplitude of which was correlated to the complementary DNA concentration. Based on this principle, the magnetic graphene field-effect transistor was utilized to detect single-stranded DNA with detection limition of 1 pM. The results were rationalized using a model wherein the magnetic force causes the DNA strand to bend, thereby resulting in magnetic nanobeads/DNA modulation of the double conductive layer of graphene transistors. Furthermore, since a periodic magnetic field could be introduced to produce a periodic impedance changes of MGFETs, sampling integration could be used to improve the signal-to-noise ratio efficiently by increasing the number of periods of the external magnetic field. Therefore, a novel biosensor for DNA detection with high sensitivity has been presented in this work. Based on the detection principle, this system may also be a potential tool for detecting other bio-molecules, cells, etc.

Front Pharmacol ; 10: 92, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30814950


Objective: To evaluate therapeutic efficacy of different combined antimicrobial treatments against Acinetobacter baumannii ventilator-associated pneumonia (VAP). Methods: Clinical outcomes were retrospectively analyzed to elucidate the efficacy of four combined antimicrobial regimens. The chessboard and micro broth dilution methods determined the minimum inhibitory concentrations (MICs) of four antiseptic drugs singly used and combined two drugs against 36 isolates of multidrug-resistant (MDR) A. baumannii. Results: The incidence of VAP was approximately 6.9% (237/3424) between January 1, 2015 and December 31, and 35.9% (85/237) of the cases were caused by A. baumannii. Among these cases, 60 belonged to AB-VAP, for whom antimicrobial treatment plan was centralized and clinical data was complete. Moreover, all 60 strains of A. baumannii were MDR bacteria from reports microbiological laboratory. Resistance rate was lowest for amikacin (68.3%) and ampicillin sulbactam (71.7%). Resistance rate for imipenem increased from 63.2 to 90.9% during the 3 years. However, in these 60 cases of AB-VAP, the combination between 4 antibiotics was effective in most cases: the effective rate was 75% (18/24) for sulbactam combined with etilmicin, 71.4% (10/14) for sulbactam combined with levofloxacin, 72.7% (8/11) for meropenem combined with etilmicin, and 63.6% (7/11) for meropenem combined with levofloxacin. There was no statistical difference between four regimens (P > 0.05). Sulbactam combined with etilmicin decreased 1/2 of MIC50 and MIC90 of sulbactam while the decreases in etilmicin were more obviously than single drug. When adopting meropenem combined with levofloxacin or etilmicin, the MIC of meropenem reduced to 1/2 of that in applying single drug. As for sulbactam or meropenem combined with levofloxacin, it also lessened the MIC50 of levofloxacin to 1/2 of that for single drug. FIC results suggested that the effects of four combined antimicrobial regimens were additive or unrelated. When sulbactam was combined with etimicin, the additive effect was 63.89%. Conclusion: Drug combination sensitivity test in vitro may be helpful for choosing antimicrobial treatment plans. Sulbactam or meropenem as the basis of treatment regimens can function as the alternatives against AB-VAP. Sulbactam combined with etimicin has been regarded as a recommended regimen in Suizhou, Hubei, China.

Surg Infect (Larchmt) ; 20(4): 292-297, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30785859


Background: Intra-cranial infection with Acinetobacter baumannii is a tough problem because of the presence of multi-resistance and poor drug penetration through the blood-brain barrier. Such intra-cranial infections can lead to serious complications and death. We retrospectively analyzed the culture results and clinical characteristics of patients with intra-cranial infections in our hospital and suggested intravenous (IV) meropenem and intra-thecal (IT) amikacin therapy may be effective in the management of A. baumannii infection. Case presentation: We reported four cases of post-neuro-surgical A. baumannii intra-cranial infection whose clinical futures were high fever and consciousness disturbance. Our patients were treated successfully with IV meropenem and IT amikacin. Conclusion: We presented our cases of pandrug-resistant A. baumannii intra-cranial infection that was managed successfully with a systemic provision of IV meropenem and IT amikacin. Therefore, these cases exemplify that systemic administration of IV meropenem and IT amikacin can be a good therapeutic option against A. baumannii intra-cranial infection when colistin is not available.

Infecções por Acinetobacter/tratamento farmacológico , Amicacina/administração & dosagem , Antibacterianos/administração & dosagem , Infecções do Sistema Nervoso Central/tratamento farmacológico , Meropeném/administração & dosagem , Procedimentos Neurocirúrgicos/efeitos adversos , Infecção da Ferida Cirúrgica/tratamento farmacológico , Infecções por Acinetobacter/patologia , Acinetobacter baumannii/isolamento & purificação , Administração Intravenosa , Adulto , Idoso , Infecções do Sistema Nervoso Central/patologia , Feminino , Humanos , Injeções Espinhais , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Infecção da Ferida Cirúrgica/patologia , Resultado do Tratamento
Sci Rep ; 6: 32855, 2016 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-27619006


The onion maggot, Delia antiqua, is a devastating pest of liliaceous crops and current control measures fail to avert pesticide residues, threats to agroecosystem, and costly expenditures. Insect growth regulators (IGRs) are used as trypetid pest chemosterilants for their suppression on adult fertility and fecundity, but their effects on onion flies are unknown. Here, three IGRs (lufenuron, cyromazine, pyriproxyfen) were incorporated into baits to evaluate their effects on onion fly survival, fecundity, fertility, susceptibility of adults in different ages and offspring development. Lufenuron and cyromazine did not affect survival of new-emerged adults, but lufenuron inhibited adult fertility without affecting fecundity, and cyromazine reduced fertility and fecundity. Differently, pyriproxyfen enhanced fecundity within 10 days after treatment, while it reduced adult survival without affecting fertility. The fertility of younger adults was affected by lufenuron and cyromazine whereas the fecundity was affected with cyromazine and pyriproxyfen. For offspring of onion flies treated with lufenuron or cyromazine, most of larvae died within 5 days after hatch, but surviving larvae pupated and emerged normally. Pyriproxyfen did not affect offspring larval survival or pupation but affected pupal emergence. Thus, lufenuron and cyromazine could be potential chemosterilants for onion flies.

Benzamidas/farmacologia , Dípteros/crescimento & desenvolvimento , Hormônios Juvenis/farmacologia , Piridinas/farmacologia , Triazinas/farmacologia , Animais , Dípteros/efeitos dos fármacos , Fertilidade/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Praguicidas/farmacologia , Pupa/crescimento & desenvolvimento
Med Chem ; 10(3): 304-17, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24059684


Systematic mono-deoxylation of the four hydroxyl groups in the glucose moiety in dapagliflozin led to the discovery of 6-deoxydapagliflozin 1 as a more active sodium-dependent glucose cotransporter 2 (SGLT2) inhibitor (IC50 = 0.67 nM against human SGLT2 (hSGLT2) vs 1.16 nM for dapagliflozin). It exhibited more potent blood glucose inhibitory activity in rat oral glucose tolerance test and induced more urinary glucose in rat urinary glucose excretion test than its parent compound dapagliflozin.

Compostos Benzidrílicos/farmacologia , Desoxiglucose/análogos & derivados , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Descoberta de Drogas , Hipoglicemiantes/farmacologia , Inibidores do Transportador 2 de Sódio-Glicose , Animais , Compostos Benzidrílicos/administração & dosagem , Compostos Benzidrílicos/química , Glicemia/efeitos dos fármacos , Desoxiglucose/administração & dosagem , Desoxiglucose/química , Desoxiglucose/farmacologia , Relação Dose-Resposta a Droga , Teste de Tolerância a Glucose , Humanos , Hipoglicemiantes/síntese química , Hipoglicemiantes/química , Estrutura Molecular , Ratos , Transportador 2 de Glucose-Sódio , Relação Estrutura-Atividade