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1.
ACS Appl Mater Interfaces ; 12(4): 4815-4820, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31898447

RESUMO

Taking the advantages of excellent optical properties, biocompatibility, and photostability of carbon dots, herein, we developed polarity-sensitive polymer carbon dots (PCDs) for visualizing of cellular polarity to real-time monitoring autophagy changes without perturbing the cellular status. The PCDs can be prepared by simply mixing dopamine (DA), H2O2, and o-phenylenediamine (o-PDA) in a common beaker without the need for any special equipment or external energy supply, and the preparation could be completed within 3 min at room temperature. Interestingly, the polarity-sensitive PCDs could emit various types of fluorescence and are insensitive to the excitation light when dispersed in different water/dioxane systems with different polarities. Based on the polarity-sensitive emission of the PCDs, the change of polarity during autophagy has been successfully monitored in living cells. Moreover, the change of polarity detected by PCDs is autophagy-specific (does not occur during apoptosis), occurs under different autophagy-inducing situations (starvation, rapamycin, and trehalose), and requires a normal autophagic flux, showing that PCDs rapidly prepared by polymerization cross-linking at room temperature can be functionally applied in the case of autophagy-related physiological or pathological processes.

2.
Medicine (Baltimore) ; 98(43): e17585, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31651864

RESUMO

This study sought to examine the human immunodeficiency virus type 1 (HIV-1) genetic diversity on drug resistance among men who have sex with men (MSM) with virologic failure in antiretroviral therapy (ART), and investigate linking-associated factors for genetic transmission networks.Seven hundred and thirty-four HIV-positive MSM with virologic failure in ART were recruited into our study from 2011 to 2017. HIV-1 pol gene sequences were used for phylogenetic and genotypic drug resistance analyses. The drug resistance mutations were determined using the Stanford University HIV Drug Resistance Database. The genetic transmission networks were analyzed for CRF01_AE and CRF07_BC sequences by the genetic distance-based method.Of 734 subjects, 372 (50.68%) showed drug resistance, in which CRF01_AE and CRF07_BC were the predominating subtypes. Drug resistance more frequently occurred in non-nucleoside reverse transcriptase inhibitors (NNRTIs) treatment (48.64%), and followed by nucleoside reverse transcriptase inhibitors (NRTIs) (36.51%) and PIs (4.03%). The most common drug resistance-associated mutations in protease inhibitors (PIs), NRTIs and NNRTIs were K20I/R, M184V/I and K103N/KN, respectively. For 283CRF01_AE sequences, 64 (22.61%) fell into clusters at a genetic distance of 0.011, resulting in 17 clusters ranging in size from 2 to 16 individuals. For 230 CRF07_BC sequences, 66 (28.69%) were connected to at least one other sequence with 0.005 genetic distances, resulting in 8 clusters ranging in size from 2 to 52 individuals. Individuals who showed drug resistance to ART were less likely to fall into clusters than those who did not. The genetic linkage was robust by the exclusion of sites associated with drug resistance.CRF01_AE and CRF07_BC were the main strains among MSM with virologic failure in ART, and the drug resistance more frequently occurred in NNRTIs, followed by NRTIs and PIs. Genetic transmission networks revealed a complexity of transmission pattern, suggesting early-diagnosis and in-time intervention among MSM.


Assuntos
Fármacos Anti-HIV/efeitos adversos , Farmacorresistência Viral/genética , Infecções por HIV/tratamento farmacológico , HIV-1/genética , Inibidores da Transcriptase Reversa/efeitos adversos , Adolescente , Adulto , China , Homossexualidade Masculina , Humanos , Masculino , Minorias Sexuais e de Gênero/estatística & dados numéricos , Falha de Tratamento , Adulto Jovem
3.
Int J Biometeorol ; 63(12): 1707-1718, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31402400

RESUMO

Hypertension is a major public health problem in the world, and the management of hypertension has always been a research of interest. Balneotherapy, with its recreational aspect, is more acceptable than medication intake and lifestyle change for the management of hypertension. The aim of this review was to summarize the current available data on the clinical effects of head-out immersion in natural thermal mineral water (HINTMW) as the most common method of balneotherapy used in the management of hypertension. We screened the PubMed, EMBASE, Cochrane Library, China Science and Technology Journal, China National Knowledge Infrastructure, WANFANG, and China Biology Medicine disc databases and selected 12 randomized controlled trials involving a total of 1122 participants. Among 12 trials, HINTMW was taken as the only intervention in only one study, HINTMW was taken in addition to basic antihypertensive drugs in three studies, and HINTMW was taken in combination with advice to follow nonpharmacological methods in one study involving participants who partly used antihypertensive drugs, while HINTMW combined with other interventions, such as natural convalescent factor therapy, psychotherapy, exercises, nutrition therapy, and integrated care, was taken in addition to basic antihypertensive drugs in the other 7 studies. Our results showed that natural thermal mineral water immersion alone or natural thermal mineral water immersion as an adjuvant therapy to medication or natural thermal mineral water immersion combined with other interventions had no adverse effects on hypertensive patients, and most even had positive effects. However, more high-quality evidences on therapeutic effectiveness of natural thermal mineral water immersion on hypertension are needed from additional randomized controlled trials with high methodological quality.


Assuntos
Balneologia , Hipertensão , Águas Minerais , China , Humanos , Hipertensão/terapia , Ensaios Clínicos Controlados Aleatórios como Assunto
4.
Chem Pharm Bull (Tokyo) ; 67(7): 675-689, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31257323

RESUMO

An Orobanchaceae plant Cistanche tubulosa (SCHENK) WIGHT (Kanka-nikujuyou in Japanese), which is one of the authorized plant resources as Cistanches Herba in both Japanese and Chinese Pharmacopoeias, is a perennial parasitic plant growing on roots of sand-fixing plants. The stems of C. tubulosa have traditionally been used for treatment of impotence, sterility, lumbago, and body weakness as well as a promoting agent of blood circulation. In recent years, Cistanches Herba has also been widely used as a health food supplement in Japan, China, and Southeast Asian countries. Here we review our recent studies on chemical constituents from the stems of C. tubulosa as well as their bioactivities such as vasorelaxtant, hepatoprotective, and glucose tolerance improving effects.


Assuntos
Produtos Biológicos/química , Cistanche/química , Animais , Aorta Torácica/efeitos dos fármacos , Aorta Torácica/metabolismo , Produtos Biológicos/isolamento & purificação , Produtos Biológicos/farmacologia , Cistanche/metabolismo , Glicosídeos/química , Glicosídeos/isolamento & purificação , Glicosídeos/farmacologia , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Monoterpenos/química , Monoterpenos/isolamento & purificação , Monoterpenos/farmacologia , Caules de Planta/química , Caules de Planta/metabolismo , Substâncias Protetoras/química , Substâncias Protetoras/isolamento & purificação , Substâncias Protetoras/farmacologia , Vasodilatadores/química , Vasodilatadores/isolamento & purificação , Vasodilatadores/farmacologia
5.
Lab Chip ; 19(17): 2811-2821, 2019 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-31312819

RESUMO

Microalgae cells have been recognized as a promising sustainable resource to meet worldwide growing demands for renewable energy, food, livestock feed, water, cosmetics, pharmaceuticals, and materials. In order to ensure high-efficiency and high-quality production of biomass, biofuel, or bio-based products, purification procedures prior to the storage and cultivation of the microalgae from contaminated bacteria are of great importance. The present work proposed and developed a simple, sheathless, and efficient method to separate microalgae Chlorella from bacteria Bacillus Subtilis in a straight channel using the viscoelasticity of the medium. Microalgae and bacteria migrate to different lateral positions closer to the channel centre and channel walls respectively. Fluorescent microparticles with 1 µm and 5 µm diameters were first used to mimic the behaviours of bacteria and microalgae to optimize the separating conditions. Subsequently, size-based separation in Newtonian fluid and in viscoelastic fluid in straight channels with different aspect ratios was compared and demonstrated. Under the optimal condition, the removal ratio for 1 µm microparticles and separation efficiency for 5 µm particles can reach up to 98.28% and 93.85% respectively. For bacteria and microalgae cells separation, the removal ratio for bacteria and separation efficiency for microalgae cells is 92.69% and 100% respectively. This work demonstrated the continuous and sheathless separation of microalgae from bacteria for the first time by viscoelastic microfluidics. This technique can also be applied as an efficient and user-friendly method to separate mammalian cells or other kinds of cells.

6.
J Sep Sci ; 42(17): 2762-2770, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31207093

RESUMO

Tianma-Gouteng granule has been used for the treatment of hypertension, headache, and stroke in China. However, the metabolism of Tianma-Gouteng granule has not been clear. In the present study, an ultra high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry method has been developed for rapid identification of 35 prototypes and 43 metabolites in human and rat urine after single oral administration of Tianma-Gouteng granule. The results showed that glucuronidation and sulfation were the main metabolic pathways for flavonoids, alkaloids, iridoidic glycosides, anthraquinones, phenols, and stilbenes that were found in Tianma-Gouteng granule. Moreover, a validated ultra high performance liquid chromatography coupled with tandem mass spectrometry method was applied for the quantification of 14 compounds in rat urine after an oral administration of Tianma-Gouteng granule (2.5 g/kg). During 0-48 h after dosing, the cumulative excretion rates of nine prototype components were 53% for gastrodin, 0.07∼1.6% for geniposide, baicalin and baicalein, wogonoside, rhynchophylline and isorhynchophylline, leonurine, and emodin, indicating that urinary excretion is the major way for gastrodin to eliminate from the body. This study provides a comprehensive understanding of metabolism and excretive kinetics of Tianma-Gouteng granule in human and/or rat, and helpful information for screening of its active components in vivo and clinical application.


Assuntos
Medicamentos de Ervas Chinesas/química , Compostos Fitoquímicos/urina , Animais , Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas/metabolismo , Humanos , Masculino , Compostos Fitoquímicos/metabolismo , Ratos , Ratos Sprague-Dawley , Espectrometria de Massas em Tandem
7.
Inorg Chem ; 58(13): 8775-8786, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31194528

RESUMO

A series of homonuclear rare-earth (RE) metal complexes (1Y, 2Yb, 3Nd, and 4La) and heteronuclear RE-Zn complexes (1Y-Zn, 3Nd-Zn, and 5Sm-Zn) stabilized by ethanolamine-bridged bis(phenolato) ligands was prepared and structurally characterized. Heteronuclear complexes are assembled through bridging acetate ligands, and their formation and characterization add to the diversity of 3d-4f complexes. Their activities in mediating reactions of CO2 and epoxides were evaluated and compared. Heteronuclear RE-Zn complexes found application in the copolymerization of cyclohexene oxide and CO2, giving rise to acetate-group-capped copolymers. Homonuclear complexes showed good activity in catalyzing the cycloaddition of variously monosubstituted epoxides and CO2 (1 bar), generating cyclic carbonates in 65-96% yield. For sterically hindered disubstituted epoxides, good yields of 60-91% were achieved in the presence of 10 bar CO2.

8.
Talanta ; 203: 220-226, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31202329

RESUMO

Biothiols play important roles in regulating redox balance in biological systems, but their discrimination is challengeable. In this work, a colorimetric nanosensing array for biothiols was established, which was composed of gold nanorods (AuNRs) and metal ions (Hg2+, Pb2+, Cu2+, Ag+). By employing label-free AuNRs as the colorimetric probe, and the color and spectral changes of AuNRs as the output signal, principal component analysis (PCA) was applied to processing the signal and generating a clustering map. Due to the different binding affinity between biothiols and metal ions, AuNRs exhibited a unique pattern to form a fingerprint-like colorimetric array, which was able to discriminate five biothiols by the naked eyes. This strategy combines PCA and sensor array to achieve rapid and accurate discrimination and detection of biothiols. In addition, the method shows the great potential in analysis of biothiols in human urine samples.


Assuntos
Colorimetria/métodos , Ouro/química , Nanotubos/química , Compostos de Sulfidrila/urina , Acetilcisteína/urina , Cisteamina/urina , Cisteína/urina , Glutationa/urina , Homocisteína/urina , Humanos , Análise de Componente Principal
9.
Cancer Med ; 8(8): 4043-4054, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31134761

RESUMO

BACKGROUND: Most mammary Paget disease (MPD) is associated with underlying in situ or invasive breast cancer. The objective of this study was to compare the clinicopathological characteristics and survival outcomes between breast cancer with Paget disease (PD) and breast cancer alone. METHODS: From the Surveillance, Epidemiology, and End Results (SEER) database, 2000-2015, of the US National Cancer Institute, we identified 1569 women who had PD with invasive ductal carcinoma (PD-IDC) and 1489 women who had PD with ductal carcinoma in situ (PD-DCIS). Independent demographic and clinicopathological variables as well as survival outcomes of these patients were compared to patients with the corresponding breast cancer without concomitant PD. RESULTS: PD-IDC and PD-DCIS both had worse survival outcomes and poorer tumor characteristics than the corresponding disease without PD. Contrary to in the breast cancer alone groups, in the breast cancer with PD groups, the HR status (P = 0.182 in PD-IDC and P = 0.371 in PD-DCIS), HER2 status (P = 0.788 in PD-IDC and P = 0.643 in PD-DCIS), and combined molecular subtype (P = 0.196 in PD-IDC and P = 0.853 in PD-DCIS) were not found to affect disease prognosis. After matching tumor characteristics and treatment approaches, PD-IDC as well as PD-DCIS exhibited no significant difference in disease prognosis with corresponding IDC and DCIS. Finally, by comparative analysis, a kind of PD-DCIS (ICD-O-3 code 8543/3) showed many invasive behaviors (31.8% of 8543/3 patients had stage I-III cancer) and was associated with worse survival outcomes than the other type of PD-DCIS. CONCLUSIONS: Breast cancer with concomitant PD was associated with more aggressive tumor characteristics and worse survival outcomes. The HR status, HER2 status, and combined molecular subtype could not affect the prognosis of breast cancer with PD. Moreover, a portion of the PD-DCIS cases were invasive breast cancer cases that required special treatment.

10.
Analyst ; 144(12): 3886-3891, 2019 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-31115404

RESUMO

Food allergy is an abnormal immune response of the immune system to some foods, which has caused great harm to people's health. Therefore, it is particularly important to detect allergens in food. In this article, a hybridization chain reaction (HCR) was coupled with gold nanoparticles (AuNPs) to detect the allergen genes of peanut, soybean and sesame DNAs. Two hairpin probes (H1 and H2) were designed for the allergen target genes of peanut, soybean and sesame DNAs. In the presence of target DNA, the hybridization chain reaction was triggered by it producing long double-stranded DNA (dsDNA) products. In the gold nanoparticle system, long dsDNA couldn't be adsorbed on the surface of AuNPs. When the concentration of salt ions in the solution increased, gold nanoparticles accumulated and led to a decrease of ultraviolet absorption. In the absence of target DNA, no hybridization chain reaction occurred. The hairpin probes could be adsorbed on the surface of AuNPs and no accumulation happened for gold nanoparticles even if the concentration of salt ions in the solution was increased. This method required no enzymes and had a strong specificity, so it was very easy to distinguish target DNA from non-target DNA. The detection limit of three allergens detected by this method was as low as 0.5 nM. The feasibility of this method for the detection of commercial commodities had been demonstrated by the successful detection of the DNAs extracted from commercial commodities, which were treated with extreme thermostable single-stranded binding protein (ET SSB).


Assuntos
Alérgenos/genética , DNA/análise , Ouro/química , Nanopartículas Metálicas/química , Adsorção , Arachis/genética , Sequência de Bases , Colorimetria/métodos , DNA/genética , Sondas de DNA/química , Sondas de DNA/genética , Sequências Repetidas Invertidas , Limite de Detecção , Técnicas de Amplificação de Ácido Nucleico/métodos , Hibridização de Ácido Nucleico , Sesamum/genética , Soja/genética
11.
Inorg Chem ; 58(11): 7545-7553, 2019 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-31074971

RESUMO

Heterobis(carbene) complexes of palladium(II) and gold(I) containing expanded-ring N-heterocyclic carbenes (erNHCs) have been prepared in order to study their electronic properties. erNHCs with mesityl substituents were found to exhibit anisotropic interferences, which hampered ranking of their donicities by 13C NMR spectroscopy. The anisotropy effects were found to be stronger in the linear gold complexes, where a smaller coordination number allows the wingtips to spread out more. erNHCs with flexible N-benzyl groups are more suitable, and their donor strengths were found to gradually increase from five- to seven-membered heterocycles. The same trend can also be obtained by comparing the 1 J(C-H) coupling constants of the respective salts, although significant differences between seven- and eight-membered erNHCs could not be detected. The % Vbur values of erNHCs obtained from structures of their palladium and gold complexes revealed that the anisotropic interferences increase with overall steric bulk.

12.
Dalton Trans ; 48(15): 4894-4905, 2019 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-30924481

RESUMO

The boroxide ligand [OBAr2]- (Ar = Mes, Trip) is shown to be able to support both UIII and UIV centres for the first time. The synthesis and structures of homoleptic and heteroleptic UIII and UIV complexes are reported. The UX3 complex with larger substituents, [U(OBTrip2)3]2, exhibits greater thermal stability compared to less encumbered [U(OBMes2)3]2 but reacts with a smaller range of the small molecules tested to date. Initial studies on their capacity to participate in small molecule chemistry show that dark purple [U(OBMes2)3]2 binds and/or reductively activates a variety of small molecules such as pyridine-oxide, triphenylphosphineoxide, sulfur, and dicyclohexylcarbodiimide. While [U(OBMes2)3]2 shows no reaction with CO or CO2, [U(OBTrip2)3]2 is oxidised by both, in the former case forming [U(OBTrip2)4], and in the latter case forming a small quantity of the structurally characterised µ-carbonate product [(µ-CO3){U(OBTrip2)3}2].

13.
Chemistry ; 25(30): 7292-7297, 2019 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-30893504

RESUMO

Highly position selective alkylations of N-alkylindoles at C7-positions have been enabled by cationic zirconium complexes. The strategy provides a straightforward access to install alkyl groups at C7-positions of indoles without a complex directing group. Mechanistic studies provided support for the importance of Brønsted acids in the catalytic manifold.

14.
Nat Commun ; 10(1): 1300, 2019 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-30899009

RESUMO

Conductive elastic composites have been used widely in soft electronics and soft robotics. These composites are typically a mixture of conductive fillers within elastomeric substrates. They can sense strain via changes in resistance resulting from separation of the fillers during elongation. Thus, most elastic composites exhibit a negative piezoconductive effect, i.e. the conductivity decreases under tensile strain. This property is undesirable for stretchable conductors since such composites may become less conductive during deformation. Here, we report a liquid metal-filled magnetorheological elastomer comprising a hybrid of fillers of liquid metal microdroplets and metallic magnetic microparticles. The composite's resistivity reaches a maximum value in the relaxed state and drops drastically under any deformation, indicating that the composite exhibits an unconventional positive piezoconductive effect. We further investigate the magnetic field-responsive thermal properties of the composite and demonstrate several proof-of-concept applications. This composite has prospective applications in sensors, stretchable conductors, and responsive thermal interfaces.

15.
Sci Total Environ ; 664: 24-36, 2019 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-30743117

RESUMO

Powdered biomass adsorbents can potentially remove antibiotics from wastewater. However, recovering or separating the adsorbents after use is difficult. The preparation of mold-assisted shaping of biomass carbon foam pellets (BCFPs) without compaction and addition of binder instead of powdered adsorbent, is rarely reported. Therefore, the study explored the formation mechanism of BCFPs by using Vallisneria natans (V. natans) waste as precursor and investigated the adsorption performance and mechanisms of metronidazole (MNZ) and dimetridazole (DMZ) onto BCFPs. The optimal preparation conditions were V. natans-and-ZnCl2 mass ratio of 1:2.4, carbonization temperature of 600 °C, and time of 90 min. BCFPs exhibited uniform size, excellent floatability, and abundant micropores. The Brunauer-Emmett-Teller specific surface area, total pore volume, and micropore volume of BCFPs were 922.56 m2 g-1, 0.421 cm3 g-1, and 0.386 cm3 g-1, respectively. The adsorption process of MNZ and DMZ was both described well by pseudo-first-order kinetic model. However, the isotherm data fitted well with Langmuir for MNZ and Dubinin-Radushkevic model for DMZ, with a maximum monolayer adsorption capacity of 64.23 and 82.58 mg g-1, respectively. The nature of the adsorption process is endothermic and spontaneous. The adsorption mechanisms of MNZ and DMZ onto BCFPs were mainly hydrogen bonding, π-π interactions, and micropore filling. Preparation of BCFPs with high mechanical strength and excellent adsorption capacity from V. natans waste without compaction and any binder is feasible. Furthermore, BCFPs are easily separated and recyclable adsorbents, and their average recovery rate was 99.6%.


Assuntos
Antibacterianos/química , Nitroimidazóis/química , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química , Adsorção , Antibacterianos/análise , Cloretos , Hydrocharitaceae , Concentração de Íons de Hidrogênio , Cinética , Nitroimidazóis/análise , Porosidade , Temperatura Ambiente , Águas Residuárias , Poluentes Químicos da Água/análise , Compostos de Zinco
16.
Anal Chem ; 91(5): 3725-3732, 2019 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-30747514

RESUMO

Although droplet-based microfluidics has been broadly used as a versatile tool in biology, chemistry, and nanotechnology, its rather complicated microfabrication process and the requirement of specialized hardware and operating skills hinder researchers fully unleashing the potential of this powerful platform. Here, we develop an integrated microdroplet generator enabled by a spinning conical frustum for the versatile production of near-monodisperse microdroplets in a high-throughput and off-chip manner. The construction and operation of this generator are simple and straightforward without the need of microfabrication, and we demonstrate that the generator is able to passively and actively control the size of the produced microdroplets. In addition to water microdroplets, this generator can produce microdroplets of liquid metal that would be difficult to produce in conventional microfluidic platforms as liquid metal has high surface tension. Moreover, we demonstrate that this generator can produce solid hydrogel microparticles and fibers using integrated ultraviolet (UV) light. In the end, we further explore the ability of this generator for forming double emulsions by coflowing two immiscible liquids. Given the remarkable abilities demonstrated by this platform and the tremendous potential of microdroplets, this user-friendly method may revolutionize the future of droplet-based chemical synthesis and biological analysis.

17.
Tohoku J Exp Med ; 247(1): 1-12, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30643108

RESUMO

Antiretroviral therapy (ART) has been introduced recently and has significantly impacted morbidity and mortality, but can also engender drug resistance. To identify the prevalence of HIV-1 drug resistance (HIVDR) among patients with antiretroviral therapy failure in Sichuan during the period from 2010 to 2016, we carried out a longitudinal study in Sichuan, a province with the highest HIV/AIDS prevalence in China. The data and blood samples were collected from HIV/AIDS patients who received ART for more than half a year. Overall 5,512 sequences were completed from 7,059 ART-failure patients, and 2,499 individuals were identified as drug resistant. Among those with HIVDR mutations identified, 25.37% were against non-nucleoside reverse transcriptase inhibitors (NNRTIs), and 1.60% was against nucleoside reverse transcriptase inhibitors (NRTIs). NRTI-resistant drugs were mainly lamivudine (3TC) (57.77%) and emtricitabine (FTC), while NNRTI-resistant drugs were mainly nevirapine (NVP) (91.13%) and efavirenz (EFV) (72.81%). The most common recombination subtypes of HIV-1 in sequenced samples were CRF07_BC (circulating recombinant form, CRF) (41.42%), followed by CRF01_AE (40.77%). Moreover, drug resistance rate increased with the prolongation of treatment time (χ2 = 14.758, P < 0.05). The overall prevalence of acquired drug resistance in HIV-1 infected patients in Sichuan was 5.47%, which has remained relatively stable from 2010 to 2016. HIV-1 CRF01_AE and CRF07_BC subtypes were the main epidemic strains, and the possibility of resistance was higher in CRF01_AE subtypes. The current study highlights the importance of acquired drug resistance surveillance over a long period.


Assuntos
Terapia Antirretroviral de Alta Atividade , Farmacorresistência Viral , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , HIV-1/fisiologia , Adulto , China/epidemiologia , Farmacorresistência Viral/genética , Epidemias , Feminino , Infecções por HIV/epidemiologia , HIV-1/genética , Humanos , Masculino , Pessoa de Meia-Idade , Mutação/genética , Filogenia , Prevalência , Falha de Tratamento , Adulto Jovem
18.
Talanta ; 196: 64-70, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30683412

RESUMO

Allergen genes of the peanut and soybean were selected as model targets. Four hairpin DNA probes, H1, H2, H3, H4 were designed. Cy3-labeled H1 and H2 were used to detect peanut DNA, while FAM-labeled H3 and H4 were used to detect soybean DNA. Graphene oxide (GO) was used as the adsorption material for capturing the hairpin probes, and as a selective fluorescence quencher to reduce the background signal. To develop an allergen gene detection system with a GO-based paper chip format, we integrated the hybridization chain reaction (HCR) with fluorescence resonance energy transfer (FRET) in our design. The results showed that in the absence of peanut DNA (TP) and soybean DNA (TS), the detection probes attached to the GO surface, which quenched their fluorescence. In the presence of TP or TS, however, complementary probe binding to the targets initiated HCR, producing long double-stranded DNA products that could not be absorbed onto the GO surface. Hence, a strong red or green fluorescent signal was generated. The detection limit for both peanut and soybean DNA was 1 nM using this method, indicating the high sensitivity of our approach. This method also exhibited good specificity and a single chip could be used to simultaneously detect two different targets.


Assuntos
Alérgenos/genética , Arachis/genética , Sondas de DNA/química , DNA de Plantas/análise , Grafite/química , Óxidos/química , Soja/genética , Antígenos de Plantas/genética , Transferência Ressonante de Energia de Fluorescência , Papel
19.
Anal Chem ; 91(6): 4077-4084, 2019 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-30669838

RESUMO

Focusing and separation of particles such as cells at high throughput is extremely attractive for biomedical applications. Particle manipulation based on inertial effects requires a high flow speed and thus is well-suited to high-throughput applications. Recently, inertial focusing and separation using curvilinear microchannels has been attracting a great amount of interest because of the linear structure for parallelization, small device footprint, superior particle-focusing performance, and easy implementation of particle separation. However, the curvature directions of these microchannels alternate, leading to variations in both the magnitude and direction of the induced secondary flow. Accumulation of this variation along the channel causes unpredictable behaviors of particles. This paper systematically investigates the inertial-focusing phenomenon in low-aspect-ratio symmetric sinusoidal channels. First, we comprehensively studied the effects of parameters such as viscosity, flow conditions, particle size, and geometric dimensions of the microchannel on differential particle focusing. We found that particle inertial focusing is generally independent of fluid kinematic viscosity but highly dependent on particle size, flow conditions, and channel dimensions. Next, we derived an explicit scaling factor and included all four dimensionless parameters (particle-blockage ratio, curvature ratio, Dean number, and channel aspect ratio) in a single operational map to illustrate the particle-focusing patterns. Finally, we proposed a rational guideline to intuitively instruct the design of channel dimensions for separation of a given particle mixture.

20.
J Food Drug Anal ; 27(1): 275-283, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30648581

RESUMO

Wu Ji Bai Feng Pill (WJBFP) is a traditional Chinese medicine (TCM) complex formula, which has been widely used in the treatment of various gynecological disorders. However, the quality control of multiple components in WJBFP is challengeable by using the methods applicable to analysis of several phytochemicals in single herbs or simple herbal preparations. The purpose of this study is to establish an ultra-high performance liquid chromatography coupled with triple quadrupole mass spectrometry (UHPLC-MS/MS) method for the quantitative determination of 20 bioactive compounds in WJBFP. The modified chromatographic conditions were achieved on an Agilent Poroshell 120 EC-C18 column with a gradient elution consisted of 0.1% formic acid in acetonitrile and 0.1% aqueous formic acid (v/v). All analytes were determined using a triple quadrupole mass spectrometry in positive or negative ionization modes with multiple reaction monitoring (MRM) mode. An UHPLC-MS/MS method was optimized and validated for linearity, limits of detection and quantification, precision, repeatability, stability and recovery. The proposed method was applied for the analysis of 20 compounds in 19 batches of commercial WJBFP products. principal component analysis and hierarchical cluster analysis were applied to evaluate intrinsic quality and to identify chemical markers most responsible for quality evaluation. In conclusion, the established method offered speedy and sensitive determination for 20 compounds and is helpful for chemical standardization of commercial WJBFP products.

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