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1.
Lab Chip ; 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38904306

RESUMO

Urinalysis is a heavily used diagnostic test in clinical laboratories; however, it is chronically held back by urine sediment microscopic examination. Current instruments are bulky and expensive to be widely adopted, making microscopic examination a procedure that still relies on manual operations and requires large time and labor costs. To improve the efficacy and automation of urinalysis, this study develops an acoustofluidic-based microscopic examination system. The system utilizes the combination of acoustofluidic manipulation and a passive hydrodynamic mechanism, and thus achieves a high throughput (1000 µL min-1) and a high concentration factor (95.2 ± 2.1 fold) simultaneously, fulfilling the demands for urine examination. The concentrated urine sample is automatically dispensed into a hemocytometer chamber and the images are then analyzed using a machine learning algorithm. The whole process is completed within 3 minutes with detection accuracies of erythrocytes and leukocytes of 94.6 ± 3.5% and 95.1 ± 1.8%, respectively. The examination outcome of urine samples from 50 volunteers by this device shows a correlation coefficient of 0.96 compared to manual microscopic examination. Our system offers a promising tool for automated urine microscopic examination, thus it has potential to save a large amount of time and labor in clinical laboratories, as well as to promote point-of-care urine testing applications in and beyond hospitals.

2.
Mikrochim Acta ; 191(5): 237, 2024 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-38570419

RESUMO

An ultra-sensitive fluorescent biosensor based on CDs/QDs@ZIF-8 and microfluidic fluidized bed was developed for rapid and ultra-sensitive detection of multiple target bacteria. The zeolitic imidazolate frameworks (ZIF-8) act as the carrier to encapsulate three kinds of fluorescence signal molecules from the CDs/QDs@ZIF-8 signal amplification system. Besides, three kinds of target pathogenic bacteria were automatically, continuously, and circularly captured by the magnetic nanoparticles (MNPs) in the microfluidic fluidized bed. The neutral Na2EDTA solution was the first time reported to not only dissolve the ZIF-8 frameworks from the MNPs-bacteria-CDs/QDs@ZIF-8 sandwich complexes, but also release the CDs/QDs from sandwich complexes with no loss of fluorescence signal. Due to the advantages of signal amplification and automated sample pretreatment, the proposed fluorescent biosensor can simultaneously detect Escherichia coli O157:H7, Salmonella paratyphi A, and Salmonella paratyphi B as low as 101 CFU/mL within 1.5 h, respectively. The mean recovery in spiked milk samples can reach 99.18%, verifying the applicability of this biosensor in detecting multiple bacteria in real samples.


Assuntos
Técnicas Biossensoriais , Escherichia coli O157 , Pontos Quânticos , Zeolitas , Microfluídica , Corantes
3.
Biosens Bioelectron ; 241: 115673, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37717422

RESUMO

To better respond to biosecurity issues, we need to build good technology and material reserves for pathogenic microorganism screening. Here, we designed an electrochemical/optical signal probe with a common fluorophore and an electrochemically active group, breaking the previous perception that the signal probe is composed of a fluorophore and a quenching group and realizing the response of three signals: electrochemistry, fluorescence, and direct observation. Then, we proposed a homogeneous electrochemical nucleic acid detection system based on CRISPR/Cas named "HELEN-CR" by integrating free electrochemical/optical signal probes and Cas13a cleavage, achieving a limit of detection of 1 pM within 25 min. To improve the detection sensitivity, we applied recombinase polymerase amplification to amplify the target nucleic acid, achieving a limit of detection of 30 zM within 45 min. Complemented by our self-developed multi-chamber microfluidic chip and portable electrochemical instrument, simultaneous detection of multiple pathogens can be achieved within 50 min, facilitating minimally trained personnel to obtain detection results quickly in a difficult environment. This study proposes a simple, scalable, and general idea and solution for the rapid detection of pathogenic microorganisms and biosecurity monitoring.

4.
Eng Life Sci ; 20(11): 494-503, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33204236

RESUMO

Shiga toxin-producing Escherichia coli (STEC) infection causes a series of diseases that are highly pathogenic and deadly in humans and animals, seriously endangering public health. Of the pathogenic factors within STEC, the two groups of Shiga toxin (Stx) consisting Stx1 and Stx2 plays a prominent role in the pathogenesis of STEC infection. In this study, we developed single-target up-converting phosphor technology-based lateral flow assay (Stx-UPT-LFA) for the rapid detection of Stx1 and Stx2, respectively, and also developed a dual-target Stx1/2-UPT-LFA based on single-target strips to detect of Stx1 and Stx2 at the meantime within 20 min. We choose the purified Stx1 and Stx2 standard samples, and the optimum monoclonal antibody (namely 8E7-E6, 2F6-F8 for Stx1 and S1D8, S2C4 for Stx2) were selected for use in Stx-UPT-LFA in double-antibody-sandwich mode. The sensitivities of single-target Stx-UPT-LFA for both Stx1 and Stx2 were 1 ng mL-1 with accurate quantitation ranges of 1-1000 ng mL-1 and 1-800 ng mL-1 respectively. No false-negative result was found in the Stx2-UPT-LFA even with a high-test concentration up to 1000 ng mL-1. Meanwhile, both targets detection sensitivities for dual-target Stx1/2-UPT-LFA were 5 ng mL-1, and accurate quantitation ranges were 5-1000 ng mL-1 and 5-800 ng mL-1 for standard Stx1 and Stx2 solutions without cross-interference between two targets. Both techniques showed good linearities, with a linear fitting coefficient of determination(r) of 0.9058-0.9918. Therefore, the UPT-LFA could realize simultaneous detection for multiple targets on a single strip and thus to quickly determine the type of infectious Stxs. In addition, the single-target Stx1-UPT-LFA and Stx2-UPT-LFA showed excellent specificity to six toxins, even at high concentrations of 1000 ng mL-1. In conclusion, the developed Stx-UPT-LFA allows the rapid, quantitative, reliable and simultaneous detection of Stx1 and Stx2 within 20 min, providing an alternative method for clinical diagnosis of STEC infection.

5.
Menopause ; 23(3): 311-23, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26671188

RESUMO

OBJECTIVE: The study aims to evaluate the effectiveness and safety of Chinese herbal medicine granules Danzhi Qing'e formula (DZQE), Erzhi formula (EZ), and their combination (Combined formula) in the treatment of menopausal symptoms at different stages of menopause. METHODS: Women between the ages of 40 to 60 years, who met menopausal symptoms diagnostic criteria and experienced hot flushes at least 14 times/week in the last 4 weeks, were recruited to participate in a stratified randomized, double-blind, placebo-controlled clinical trial (n = 389). They received a treatment period of 8 weeks and were followed up for 4 weeks. Participants were categorized into two subgroups: 197 in the perimenopausal subgroup (menstrual disorder to 1 y after amenorrhea) and 192 in the early postmenopausal subgroup (1-5 y after amenorrhea). Participants were randomly assigned to placebo or one of the three herbal formula treatments. The primary outcome instrument was the Menopause-Specific Quality of Life (MENQOL) questionnaire. RESULTS: When analyzing the two subgroups together, DZQE markedly decreased the MENQOL total score at the end of 12th week with statistical significance (P = 0.02) and improved vasomotor symptoms after 8 weeks treatment and 4 weeks follow-up (P < 0.05). What is more, the combined formula also greatly improved the participants' vasomotor symptoms compared with placebo after the 4 weeks follow-up. No statistically meaningful difference was observed in any other outcomes among the groups. The results of subgroup analysis showed that DZQE and Combined formula were more effective than placebo in improving MENQOL total score for perimenopausal women at the end of week 12. For typical menopausal symptoms such as hot flushes and night sweats, DZQE displayed more favorable effects on early postmenopausal participants. Compared to placebo, the DZQE both showed statistically significant differences after 8 weeks treatment and 4 weeks follow-up. Although at the end of 12th week, DZQE also had better effects than placebo in the perimenopausal subgroup on vasomotor symptoms. Participants in the EZ group did not show a significant difference of any domains in MENQOL compared with participants in the placebo group. CONCLUSIONS: The DZQE formula improves the quality of life for menopausal women, especially for those with vasomotor symptoms during the whole menopausal period. The DZQE and EZ combination formula is effective only on perimenopausal symptoms.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Fogachos/tratamento farmacológico , Sudorese/efeitos dos fármacos , Adulto , Terapias Complementares , Método Duplo-Cego , Feminino , Humanos , Menopausa/efeitos dos fármacos , Menopausa/fisiologia , Pessoa de Meia-Idade , Qualidade de Vida , Inquéritos e Questionários
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