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1.
Nat Immunol ; 25(1): 54-65, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38062135

RESUMO

The nature of activation signals is essential in determining T cell subset differentiation; however, the features that determine T cell subset preference acquired during intrathymic development remain elusive. Here we show that naive CD4+ T cells generated in the mouse thymic microenvironment lacking Scd1, encoding the enzyme catalyzing oleic acid (OA) production, exhibit enhanced regulatory T (Treg) cell differentiation and attenuated development of experimental autoimmune encephalomyelitis. Scd1 deletion in K14+ thymic epithelia recapitulated the enhanced Treg cell differentiation phenotype of Scd1-deficient mice. The dearth of OA permitted DOT1L to increase H3K79me2 levels at the Atp2a2 locus of thymocytes at the DN2-DN3 transition stage. Such epigenetic modification persisted in naive CD4+ T cells and facilitated Atp2a2 expression. Upon T cell receptor activation, ATP2A2 enhanced the activity of the calcium-NFAT1-Foxp3 axis to promote naive CD4+ T cells to differentiate into Treg cells. Therefore, OA availability is critical for preprogramming thymocytes with Treg cell differentiation propensities in the periphery.


Assuntos
Ácido Oleico , Timócitos , Animais , Camundongos , Ácido Oleico/metabolismo , Timo , Linfócitos T Reguladores , Diferenciação Celular , Fatores de Transcrição Forkhead/genética
2.
Front Public Health ; 11: 1163351, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37711237

RESUMO

Background: Humanistic care pertains to the abilities, attitudes, and behaviors central to patient-centered care, contributing to patients' sense of safety and wellbeing. This study aimed to assess the satisfaction of patients with humanistic nursing care in Chinese secondary and tertiary public hospitals. Methods: A national cross-sectional survey was conducted across 30 provinces and 83 hospitals in China. Patient satisfaction with humanistic care was assessed using the Methodist Health Care System Nurse Caring Instrument (NCI), which encompasses 20 items across 12 dimensions. Each item was rated on a 7-point Likert scale, yielding a total score of 140. Multiple linear regression analysis was employed to identify factors associated with patients' satisfaction. Results: Moderate satisfaction (mean score 91.26 ± 13.14) with humanistic nursing care was observed among the 17,593 participants. Factors significantly associated with patient satisfaction included age, hospital type, presence of children, educational attainment, place of residence, family monthly income, and medical insurance type. Conclusion: The study findings highlight the importance of tailored interventions, evidence-based practice guidelines, and patient-centered care in improving patients' satisfaction with humanistic nursing care. Continuous emphasis on nursing education and professional development is crucial for enhancing humanistic care and patient satisfaction.


Assuntos
População do Leste Asiático , Satisfação do Paciente , Humanos , Povo Asiático , Estudos Transversais , Hospitais Públicos
3.
IEEE Trans Cybern ; 53(12): 8024-8034, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37703144

RESUMO

In this article, a novel switched observer-based neural network (NN) adaptive control algorithm is established, which addresses the security control problem of switched nonlinear systems (SNSs) under denial-of-service (DoS) attacks. The considered SNSs are described in lower triangular form with external disturbances and unmodeled dynamics. Note that when an attack is launched in the sensor-controller channel, the controller will not receive any message, which makes the standard backstepping controller not workable. To tackle the challenge, a set of NN adaptive observers are designed under two different situations, which can switch adaptively depending on the DoS attack on/off. Further, an NN adaptive controller is constructed and the dynamic surface control method is borrowed to surmount the complexity explosion phenomenon. To eliminate double damage from DoS attacks and switches, a set of switching laws with average dwell time are designed via the multiple Lyapunov function method, which in combination with the proposed controllers, guarantees that all the signals in the closed-loop system are bounded. Finally, an illustrative example is offered to verify the availability of the proposed control algorithm.

4.
J Multidiscip Healthc ; 16: 717-730, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36959865

RESUMO

Background: International stroke care guidelines recommend the routine assessment and management of psychological and emotional problems in patients and their families after a stroke. This study aimed to explore the humanistic nursing needs of patients with stroke and their families and provide a basis for the construction of humanistic nursing practice guidelines for advanced stroke. Methods: From September to October 2019, using the descriptive phenomenological research method, a semi-structured interview outline was formed based on a literature review and subject group discussions. A targeted sampling method was used to investigate 21 patients with stroke and 21 family members, respectively, and their care needs were investigated in depth. Colaizzi's thematic cluster analysis was used to analyse the data, and a total of 6 themes and 14 sub-themes were summarised. Results: The 6 themes and 14 sub-themes were as follows: ① psychological care, ② security concerns (professional personal integrity, timely response), ③ emotional care (service consciousness, positive incentives, empathy, effective communication, provision of a communication platform, personalised care), ④ respect for rights, ⑤ rehabilitation care (rehabilitation programme, professional guidance, rehabilitation configuration, continuation of services) and ⑥ family care (physical and psychological support, care guidance). Conclusion: Among the humanistic care needs of patients with stroke and their families, the most basic physiological care accounts for the largest proportion of emotional and rehabilitation care, followed by safety care, respect for rights and family care. Based on the actual humanistic care needs of patients with stroke and their families, the practical effect of humanistic care in stroke wards can be improved. This study provides a reference for the construction of humanistic nursing practice guidelines for late stroke.

5.
J Chromatogr A ; 1689: 463744, 2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36610187

RESUMO

In food safety monitoring, on-site and simultaneous detection of a variety of insecticides with different concentrations in the same matrix is necessary. However, the task remains challenging. In this study, a novel nitrogen and sulfur co-doped carbon dot (N, S-CD) was synthesized and used as a QuEChERS clean-up reagent to reduce matrix interferences in the determination of insecticides in vegetables. In addition, a portable mass spectrometer (µ-MS) was employed, without chromatography separation, to directly determine neonicotinoids, carbamates, and benzopyrazole insecticides (with acetamiprid, imidacloprid, thiamethoxam, fipronil, and carbofuran as models) in the pretreated samples. The N,S-CD µ-MS method exhibited effective clean-up performance with satisfactory matrix effects between -15.2% and 15.7%. The recoveries of spiked vegetable samples ranged from 82.2% to 109.7% for the five target insecticides, and the relative standard deviations (RSDs) ranged from 3.8% to 16.5%. The linear ranges were from 2.0 to 5.0 ng/g, with low detection limits (LOD) from 0.5 to 1.0 ng/g. Moreover, the total pretreatment and detection time was within 20 min. Thus, the incorporation of N,S-CD with QuEChERS extraction, together with the portable µ-MS system, could be a promising and feasible strategy for on-site, rapid, and simultaneous detection of various insecticides in vegetables.


Assuntos
Inseticidas , Resíduos de Praguicidas , Inseticidas/análise , Verduras/química , Carbamatos/análise , Espectrometria de Massas em Tandem/métodos , Neonicotinoides/análise , Pirazóis , Resíduos de Praguicidas/análise , Cromatografia Líquida de Alta Pressão/métodos
6.
Biosens Bioelectron ; 220: 114852, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36345085

RESUMO

Live foodborne pathogens proliferate rapidly and do great harm to human health, which requires appropriate methods to supervise. In this work, a portable adenosine triphosphate (ATP) bioluminescence sensor with high specificity for live E. coli O157:H7 strain synergistically enhanced by orientated phage-modified stir bar extraction and bio-proliferation was developed. In brief, the selected phages were directionally immobilized on the poly(diallyldimethylammonium chloride)-modified gold stir bar as the bioreceptor. Following the simple stir bar absorptive extraction and bio-proliferation in the Luria-Bertani medium, the number of captured E. coli O157:H7 exploded. Finally, it was quantified by a portable ATP bioluminescence sensor. Benefitting from the high specificity of phage and simple signal dual-amplification strategy, the proposed biosensor achieved the recognition of live bacteria at strain level with superior sensitivity. Also, the portable signal readout made it suitable for on-site detection. Under optimal conditions, this bioassay provided a detectable range of 102-107 CFU mL-1 with a low detection limit of 30 CFU mL-1 within 30 min. The detection results for real samples demonstrated that there were no differences between the assay and the plate counting method, while the detection time was largely shortened. Furthermore, the assay gives a novel path for the point-of-care test (POCT) of live E. coli strain, which is promising to be extended to other virulent strains measurement with corresponding phages.


Assuntos
Bacteriófagos , Técnicas Biossensoriais , Escherichia coli O157 , Humanos , Microbiologia de Alimentos , Trifosfato de Adenosina , Técnicas Biossensoriais/métodos , Proliferação de Células
7.
Anal Chim Acta ; 1237: 340611, 2023 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-36442940

RESUMO

It was critically important to develop some sensitive, rapid, and specific imaging or detection methods for the virulent strain in food safety monitoring. In the study, a novel tetraphenyl mono-phenylboronic acid dye (TPE-PBA) with good aggregation-induced emission (AIE) features and high combining capacity towards bacteria was first synthesized. With TPE-PBA as a signal tag, a sandwich-type AIE probe-linked phage sorbent assay was developed for imaging and detecting virulent strains using Escherichia coli O157:H7 (E. coli O157:H7) as a representative. In the assay, phages for E. coli O157:H7 were firstly fixed on the bottom of a 96-well plate to specifically capture the strain, then the TPE-PBA signal tag was added and incubated with the captured strain to produce the phage/E. coli O157:H7/TPE-PBA complex. The complex could produce intensive AIE fluorescence being proportional to the amount of E. coli O157:H7 with a detection limit of 30 CFU mL-1 within 30 min. Simultaneously, the strain could be imaged in the plate with good anti-photobleaching and AIE effects. The results demonstrated the AIE-linked phage sorbent assay with a TPE-PBA signal tag could provide a suitable platform for rapid and specific detection and imaging of virulent strains. Therefore, it exhibited good application prospects in the on-site monitoring of food pathogens.


Assuntos
Bacteriófagos , Escherichia coli O157 , Bactérias , Bioensaio , Inocuidade dos Alimentos
8.
J Chromatogr A ; 1685: 463614, 2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36347073

RESUMO

It is crucially important to develop simple, selective, and rapid extraction pretreatments and analytical methods to detect microcystins (MCs) in food samples with complex matrices. In this study, a magnetic self-assembled covalent organic framework (COF) adsorbent was synthesized via a facile approach by using a one-pot reaction of 1,6-bis(4-formylphenyl)-3,8-bis(4-aminophenyl)pyrene (BFBAPy) as precursors to assemble amino-functionalized magnetic Fe3O4-NH2 nanoparticles (Fe3O4@Py-COF, simplified as mCOF). The superparamagnetic mCOF is found to exhibit a high specific surface area, abundant nanopores and good stability. In particular, adsorption experiments demonstrate that mCOF exhibits a good adsorption capability, efficiency and some specificity to MCs. The mCOF was applied for magnetic solid phase extraction (MSPE) of two kinds of MCs (MC-LR and MC-RR) from aquatic samples followed by high-performance liquid chromatography-diode array detection (HPLC-DAD). Under the optimized conditions, good linearity is obtained in the range of 10-1000 µg/kg (R2≥0.9989), the limits of detection are 3.0-4.5 µg/kg, and the relative standard deviations (RSDs) are lower than 4.9% (n=5). The extraction recoveries are also satisfactory (84.2%-105%). These results demonstrate that the developed method can be used as a good alternative method for the selective determination of MCs in complex aquatic foods.


Assuntos
Estruturas Metalorgânicas , Cromatografia Líquida de Alta Pressão , Microcistinas/análise , Extração em Fase Sólida/métodos , Adsorção , Fenômenos Magnéticos , Limite de Detecção
10.
J Chromatogr A ; 1681: 463456, 2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-36095973

RESUMO

In this work, a disposable and inexpensive bamboo stir bar containing an organic membrane was constructed to perform stir bar sorptive extraction (SBSE), followed by portable mass spectrometry to achieve on-site detection of four residual drugs (malachite green, crystal violet and their metabolites) in fishes. The entire method uses only microliter quantities of organic solvents, enabling environmentally friendly pretreatment. The portable mass spectrometer can simultaneously detect four target analytes in a sample in approximately ten seconds. Under the optimal conditions, the proposed method was successfully applied to simultaneously detect four drugs in fish samples with detection limits of 0.16-0.59 µg/kg. The spiked recoveries for mandarin fish and lateolabrax maculatus were 74.5-96.5%, with relative standard deviations (RSD) of 4.4-16%. In addition, the matrix effects of the four analytical targets in the method were experimentally verified to range from 7.30% to 20.62%. The method can potentially be extended to the on-site detection of other veterinary drug residues in foods.


Assuntos
Violeta Genciana , Drogas Veterinárias , Animais , Peixes , Limite de Detecção , Espectrometria de Massas , Reprodutibilidade dos Testes , Corantes de Rosanilina , Solventes
11.
Front Public Health ; 10: 915472, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36016905

RESUMO

Purpose: To construct humanistic nursing practice guidelines suitable for stroke patients. Design: This study was a development and validation study of guidelines using multiple methods, including literature review, qualitative research, questionnaire survey, thematic discussion, and Delphi expert consultation. Methods: Twenty-five experts from seven provinces and municipalities in China were interviewed over two rounds from December 2020 to February 2021. The first-level index was scored for importance and rationality, while the second-level index was scored for importance and feasibility using a five-point Likert scale. Delphi data was collected via a paper version of the questionnaire. The coefficients of variation and coordination were used to represent the degree of dispersion of expert opinions. Findings: In the two rounds of letter consultation, the questionnaire's recovery and effective rates were both 100%, while the opinion submission rates of the two rounds were 84 and 52%, respectively. Moreover, the expert authority coefficient was 0.91, and the coordination coefficients of expert opinions in the first round were as follows: importance of 0.03 and rationality of 0.07 for the first-level index; importance of 0.09 and feasibility of 0.11 for the secondary index. In round two, the coordination coefficients of expert opinions were as follows: importance of 0.04 and rationality of 0.05 for the first-level indicators; importance of 0.12 and feasibility of 0.10 for the secondary index. The results for the secondary index were P < 0.001 for the two rounds. The humanistic nursing practice guidelines for stroke patients that were ultimately formed included five first-level indicators (physiological care, safety care, emotional care, dignity care, and rehabilitation needs) and 46 s-level indicators. Conclusion: Our results show that the "Practice Guidelines for Humanistic Nursing for Stroke" established by experts adopts Maslow's hierarchy of needs as its structural framework. It meets people's basic needs and can provide a reference for the construction of a humanistic nursing specialty practice for stroke patients. Clinical relevance: Humanistic nursing guidelines for stroke could provide a reference for the construction of humanistic nursing practice in the stroke specialty. Clinical resources: Copeptin and long-term risk of recurrent vascular events after transient ischemic attack and ischemic stroke: population-based study https://pubmed.ncbi.nlm.nih.gov/26451023/. Effectiveness and usage of a decision support system to improve stroke prevention in general practice: a cluster randomized controlled trial https://pubmed.ncbi.nlm.nih.gov/28245247/. Guidelines for adult stroke rehabilitation and recovery: a guideline for healthcare professionals from the American Heart Association/American Stroke Association https://pubmed.ncbi.nlm.nih.gov/27145936/.


Assuntos
Encaminhamento e Consulta , Acidente Vascular Cerebral , Adulto , China , Técnica Delfos , Humanos , Acidente Vascular Cerebral/terapia , Inquéritos e Questionários , Estados Unidos
12.
Front Psychiatry ; 13: 791993, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35401272

RESUMO

Background: As a special patient group, stroke patients have a significant attachment to humanistic care. However, multiple problems remain in clinical practice. Medical staff in stroke wards are the primary providers of humanistic care. Finding out the opinions of the staff that provide these medical services is vitally important for stroke patients that need access to curative and humanistic care. Objective: The aim of the study is to explore the psychological experiences of doctors, nurses, and physiotherapists during the implementation of humanistic care in stroke wards. Method: This is a qualitative phenomenological study. Medical staff (i.e., doctors, nurses, and physiotherapists) were selected from stroke wards in general hospitals (minimum level two) from 13 cities within six provinces in China. A purposive sampling method was used until saturation (n = 18). Face-to-face or video call semi-structured interviews were conducted by using a phenomenological research method. The average interview length was 60 min (range 30-90 min). The Colaizzi seven-step method was used for analysis. Results: Four themes and 12 sub-themes were extracted from the qualitative interviews of the medicine, nursing and technology staff, as follows. ➀ The ward staff reported that the behaviors of the stroke patients gradually improved when they assisted with stroke treatment idea changes, when they paid attention to solving the patients' existing problems, and when they took the initiative to create a caring atmosphere; ➁ when humanistic care in the stroke wards was carried out with consciousness and ability improvement (including proactive caring behaviors in which vocational value was not strong and in which the whole-person rehabilitation was given attention, not just implementation), the patients' behaviors improved; ➂ the stroke wards themselves were improved (the gap between the current management and the needs of medical institutions and the gap between the rehabilitation conditions and the patients' needs were addressed); and ➃ the urgent needs of the staff in the implementation of humanistic care in stroke wards were considered (the addition of full-time posts, the effective training of humanistic care, and the construction of a more harmonious doctor-patient relationship). Conclusion: In implementing humanistic care in stroke wards, the consciousness and ability of the medical staff need to be improved. In addition, the practical problems and contradictions affecting the development of humanistic care must be addressed. To improve the level of humanistic care in stroke wards, attention should be paid to the overall improvement of the personal qualities of the medical staff and the integration of a humanistic management mode.

13.
Int J Nurs Sci ; 9(1): 5-10, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34976429

RESUMO

OBJECTIVES: Major infectious disease has become a serious threat to people's health worldwide. As the world's largest healthcare workforce and the core forces fighting against the epidemic, nurses are on the frontline of this battle. A number of ethical issues have given rise to numerous concerns that have largely affected nurses in different ways as they respond to the epidemic. In addition, excessive expectations from people can exert undue pressure, which can easily lead to burnout in nurses. METHODS: In this consensus, the expert panel method was used to develop and reach a consensus. The members involved in the formation of the consensus included an expert discussion panel and a consensus writing expert group, a methodologist, and four secretaries. After 16 rounds of online expert consultation and two rounds of expert panel meetings, the writing team analyzed and reviewed the 78 amendments suggested by the experts to develop a consensus on nursing ethics for prevention and control of major infectious disease outbreaks based on the ethical vision of life care. RESULTS: This expert consensus focuses on five essential domains: the responsibilities and rights of nurses, the nurse-patient relationship, the doctor-nurse relationship, and the relationship between society and nurses throughout the epidemic. CONCLUSIONS: We hope this consensus can help nurses better understand and respond to the ethical issues and challenges in public health emergencies, and raise reasonable public expectations of the roles and responsibilities of nurses in these situations.

14.
J Pharm Anal ; 12(6): 913-922, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36605572

RESUMO

In this study, a fluorescent (FL) aptasensor was developed for on-site detection of live Salmonella typhimurium (S.T.) and Vibrio parahaemolyticus (V.P.). Complementary DNA (cDNA) of aptamer (Apt)-functionalized multicolor polyhedral oligomeric silsesquioxane-perovskite quantum dots (cDNA-POSS-PQDs) were used as encoded probes and combined with dual-stirring-bar-assisted signal amplification for pathogen quantification. In this system, bar 1 was labeled with the S.T. and V.P. Apts, and then bar 2 was functionalized with cDNA-POSS-PQDs. When S.T. and V.P. were introduced, pathogen-Apt complexes would form and be released into the supernatant from bar 1. Under agitation, the two complexes reached bar 2 and subsequently reacted with cDNA-POSS-PQDs, which were immobilized on MXene. Then, the encoded probes would be detached from bar 2 to generate FL signals in the supernatant. Notably, the pathogens can resume their free state and initiate next cycle. They swim between the two bars, and the FL signals can be gradually enhanced to maximum after several cycles. The FL signals from released encoded probes can be used to detect the analytes. In particular, live pathogens can be distinguished from dead ones by using an assay. The detection limits and linear range for S.T. and V.P. were 30 and 10 CFU/mL and 102-106 CFU/mL, respectively. Therefore, this assay has broad application potential for simultaneous on-site detection of various live pathogenic bacteria in water.

15.
Mikrochim Acta ; 188(2): 45, 2021 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-33479797

RESUMO

A pair of composite probes based on aptamer modified polyhedral oligomeric silsesquioxane-perovskite quantum dots (POSS-PQDs-Apt) as signal probe and titanium carbide (Ti3C2) MXenes as quencher were prepared for the first time. They were employed to fabricate one turn-on-type aptasensor relying on fluorescence resonance energy transfer (FRET) for Vibrio parahaemolyticus (VP) determination. The POSS-PQDs-Apt can be adsorbed on the MXenes nanosheets, and its fluorescence was quenched due to the FRET. After the composite probes were incubated with VP for 50 min, the POSS-PQDs-Apt binding with VP can be released from the surface of MXenes, and the signal recovered due to its higher affinity to the VP than MXenes. The fluorescence intensity from 519 nm emission of the system was measured at 480 nm excitation. Under In optimized conditions, the assay can determine VP in the concentration range 102 - 106 cfu/mL, and the detection limit (LOD) was 30 cfu/mL using fluorescence detection. The LOD is still 100 cfu/mL by naked eye detection which is proper for on-line monitoring VP in aquaculture water. This method was also used to detect VP in actual samples of seawater, the recovery of spiked samples was between 93% and 106%, and relative standard deviation (RSD) was between 2.7% and 6.7%. The result is consistent with the plate count. Therefore, this assay could provide a candidate platform for screening VP in aquaculture industry.


Assuntos
Aptâmeros de Nucleotídeos/química , Compostos de Organossilício/química , Pontos Quânticos/química , Titânio/química , Vibrio parahaemolyticus/isolamento & purificação , Poluentes da Água/análise , Carga Bacteriana/métodos , Técnicas Biossensoriais/métodos , Compostos de Cálcio/química , Transferência Ressonante de Energia de Fluorescência , Limite de Detecção , Óxidos/química , Água do Mar/análise , Água do Mar/microbiologia , Vibrio parahaemolyticus/química
16.
Talanta ; 222: 121456, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33167200

RESUMO

It was extremely urgent to develop some simultaneous and sensitive biosensors for detecting multiplex serum tumor markers (TMs) for early screening of cancers. Herein, a multiplex assay was developed based on the DNA-LaMnO3 (DNA-LMO) perovskite encoded probes and targets mediated competitive replacement strategy. Alpha fetoprotein (AFP), carcinoembryonic antigen (CEA) and prostate specific antigen (PSA) markers were employed as representative target TMs. Aptasensor is prepared by a series of DNA-LMO-M encode probes which were prepared by three hyperbranched DNA firstly immobilized on LMO encapsulating Pb, Cd or Cu ions. Then, three TMs aptamers were labeled on the stirring-rod and hybridized with the probes. After the developed encoded probes was incubated the TMs, the encoded probes corresponding to different TMs can be released into the supernatant through the competitive replacement. The inner metal ion can be simultaneously detected by square wave voltammetry corresponding to various TMs. Since the stirring rod can enrich many encoded probes containing a lot of metal ions, multiplex signal amplification can be realized. Due to the enrichment and easy separation of the stirring rod, the signal-to-noise ratio was also obviously improved and thus to results in good sensitivity and accuracy. Moreover, it took only 20 min to detect three targets which much faster than many same types of aptasensor. Under the optimal conditions, the low detection limit for CEA (3.6 × 10-4 ng/mL), AFP (3.4 × 10-4 ng/mL) and PSA (2.8 × 10-4 ng/mL) were obtained. Therefore, this method is likely to be used for early and sensitive screening of tumors.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Biomarcadores Tumorais , Compostos de Cálcio , Ouro , Ácidos Nucleicos Imobilizados , Íons , Limite de Detecção , Masculino , Óxidos , Titânio
17.
Dalton Trans ; 50(1): 346-354, 2021 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-33313616

RESUMO

Redox-controlled polymerization is one of the new and efficient strategies to precisely construct the microstructures of polymeric materials, and thus has received increasing attention in the chemical community. Salt metathesis of ScCl3 with 1 equiv. of Fc(1-C9H6)Li (where Fc = ferrocenyl group), followed by the addition of 2 equiv. of LiCH2C6H4NMe2-o in THF at room temperature gave the ferrocenyl functionalized half-sandwich scandium bis(o-dimethylaminobenzyl) complex [Fc(1-C9H6)]Sc(CH2C6H4NMe2-o)2 (1) in 89% isolated yield. This complex was characterized by elemental analysis, FT-IR spectroscopy, NMR spectroscopy and single-crystal X-ray diffraction. Treatment of 1 with 1 equiv. of [Ph3C][B(C6F5)4] in THF generated the THF-coordinated cationic half-sandwich scandium mono(o-dimethylaminobenzyl) complex {[Fc(1-C9H6)]Sc(CH2C6H4NMe2-o)}{[B(C6F5)4]} (2-THF2). Switching in situ between the oxidized and reduced forms of active THF-free species (originally generated from 1/[Ph3C][B(C6F5)4] in situ) resulted in the redox-controlled syndio-specific polymerization of styrene.

18.
Anal Chim Acta ; 1133: 128-136, 2020 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-32993865

RESUMO

Sensitive and rapid detection of pathogenic bacteria remains important and challenging for food safety and preventing outbreaks of foodborne disease. The major limitations of standard analytical methods for detecting vibrio parahaemolyticus (V.P) lie in their bulky equipment and tedious and long-time operation. This study presents an electrochemical aptasensor for the rapid on-site quantification of V.P in seafood. Magnetic nanoscale metal-organic frameworks (Fe3O4@NMOF) labeled with an aptamer against V.P served as capture probes, while gold nanoparticles combined with phenylboronic acid and ferrocene acted as the nanolabels. When detecting V.P, the sandwich-type complex of capture probe-V.P-nanolabel was formed and magnetically attached to a screen-printed electrode (SPE) for signal measurement. Under optimal conditions, the increase in the ferrocene electrochemical signals could assess the V.P amount; the quantified concentration range was 10-109 cfu/mL. Then, the developed signal-on sensor successfully detected V.P in real seafood samples, exhibiting many advantages. It could not only specifically enrich and rapidly separate the V.P in complex samples but also largely amplify the signal. Moreover, using compact SPE with a detection time of maximum 20 min as the measurement platform allows rapid on-site assays. Thus, the proposed method is a feasible strategy for screening V.P in seafood.


Assuntos
Aptâmeros de Nucleotídeos , Nanopartículas Metálicas , Estruturas Metalorgânicas , Vibrio parahaemolyticus , Ácidos Borônicos , Ouro , Limite de Detecção , Fenômenos Magnéticos , Metalocenos
19.
Extremophiles ; 24(3): 365, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32291524

RESUMO

In the original publication the section heading "Classification of microorganisms" appearing above the sub-section "Air and liquid circulation in the heap" in page four is incorrect. The correct section heading should be read as "Results and discussion".

20.
Extremophiles ; 24(3): 355-364, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32108913

RESUMO

Heap biooxidation method was used to evaluate the availability of Paodaoling gold ore in Anhui province, China. 15,000 tons of gold ores (≤ 10 mm in diameter) were bioxidized under mesophilic conditions. Under the synergistic effect of microbial community, arsenic and sulfur were oxidized by 42% and 38% after 80 days. Relatively, leaching of gold was improved from 36 to 78% after heap biooxidation. The sequencing results showed there were 28 operational taxonomic units identified the microbial community in the heap. The main genera were Acidithiobacillus, Ferroplasma, Acidiferrobacter and Nitrospira. According to stoichiometry, the content of microorganisms with various functions tended to be balanced. The biomass production rate was 10 g/s, the CO2 fixation rate was 18 g/s, and the oxygen consumption rate was 60 g/s. This study provides a good basis for the further design and application of heap biooxidation technology.


Assuntos
Bactérias , Acidithiobacillus , Arsênio , China , Ouro , Oxirredução
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