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Association among short-term exposure to particulate matter pollution as well as eating habits study assisted duplication technology in Lombardy, France: A new retrospective cohort research.
An Id-based test paper can be used to rapidly identify Fe3+. These results are expected to improve the development of new sensitive and specific fluorescent sensors for Fe3+.A novel surface-enhanced Raman scattering (SERS)-based analytical technique was proposed to simultaneously detect two highly pathogenic bacteria, namely, Staphylococcus aureus (S. aureus) and Listeria monocytogenes (L. mono) by using a dual-recognition pattern with wheat germ agglutinin (WGA) and nucleic acid aptamers. WGA was modified onto Fe3O4@Au magnetic nanoparticles (MNPs) for the efficient capture of S. aureus and L. mono in complex samples (orange juice, extracts of lettuce, and human urine) within 15 min. The streptavidin (SA)/aptamers co-functionalized SERS tags were fabricated by covalent attaching two different Raman reporters and SA molecules onto 45 nm Au NPs and then conjugated with two biotin-aptamers that specifically bind to their target bacteria with high affinity and stability. The combined use of high-sensitive SERS tags, WGA-mediated magnetic enrichment, and SA-mediated aptamer conjugation remarkably improved the assay sensitivity. selleck Under optimized conditions, the developed SERS biosensor can simultaneously detect the two target bacteria with high detection sensitivity ( less then 6 cells/mL), favorable linear relation (10-107 cells/mL), and high accuracy (recovery rate less then 7.03%). Therefore, the proposed SERS platform is rapid, sensitive, easy to use, and thus show potential as a tool for the timely identification of pathogenic bacteria in real samples.In this work, an auto-identify sensor was constructed for rapid and high-precision detection of L-histidine. The proposed strategy is based on the auto-identify algorithm and the aggregation of alkynyl and azide functionalized gold nanoparticles induced by the Cu+ catalyzed azides and alkynes cycloaddition (CuAAC) reaction. Specially, the color of scattering light spots for the aggregated gold nanoparticle (AuNPs) caused by CuAAC reaction was quite different from that of the monomers. However, L-histidine can bind to Cu2+ and inhibits the production of Cu+, hence preventing the aggregation of AuNPs. Therefore, there is a distinct change of color as the addition of L-histidine under dark-field microscopy. Then, L-histidine can be quantitatively detected by combining the color change with the Meanshift algorithm accurately and automatically. Such proposed method has been successfully applied for the detection of L-histidine in serum sample with satisfying result.Electrochemical (EC) detection of DNA biomarkers represents an interesting tool in molecular oncology due to its sensitivity, simplicity, low cost or rapid times of measurement. However, majority of EC assays, same as most optical-based techniques, require preceding DNA extraction step to remove other cellular components, making these assays more laborious and time-consuming. One option to circumvent this is to use LAMP (loop-mediated amplification), an isothermal amplification technique that can amplify DNA directly in crude lysates in a short time at a constant temperature. Here, we coupled the LAMP reaction with EC readout to detect DNA from the two most common oncogenic human papillomavirus (HPV) types that cause cervical cancer in women, i.e. HPV 16 and HPV 18, directly in crude lysates without a need for DNA extraction step. We show that in crude lysates, the LAMP reaction was superior to PCR, with very good selectivity on a panel of cancer cell lines and with high sensitivity, enabling detection of HPV DNA from as few as 10 cells. As a proof of principle, we applied the assay to nineteen clinical samples both from uninfected women and from women suffering from cervical precancerous lesions caused by HPV 16 or HPV 18 genotypes. Clinical samples were simply boiled for 5 min in homogenization buffer without DNA extraction step, and amplified with LAMP. We obtained excellent concordance of our assay with PCR, reaching 100% sensitivity for both genotypes, 81.82% specificity for HPV 16 and 94.12% specificity for HPV 18. Proposed assay could be a straightforward, simple, rapid and sensitive alternative for early diagnostics of precancerous cervical lesions.Natural and synthetic alkaloids are widely used for several applications, ranging from clinical purposes to criminal activities. Presumptive color tests are considered a leading tool to reveal on-scene substance identification via rapid chemical reactions that result in visual color changes. Colorimetric tests are popular due to their inherent simplicity, low cost, promptitude and portability; however, in many cases the results of such tests may not be predictable, partly because of the interference from similar species. In this proof-of-concept study, we present a paper-based microfluidic optoelectronic tongue - the so-called μOPTO - comprised of 6 indicators in lieu of one specific test and capable of discriminating 8 different alkaloid drugs (i.e. scopolamine, atropine, cocaine, morphine, ephedrine, caffeine, dipyrone and alprazolam) used for recreational, criminal and medical purposes. The wax printing method was employed to fabricate the microfluidic analytical device with six circular spots for reagent accommodation connected to a centered spot to enable simultaneous reactions with one sample injection. Digital images were obtained using an ordinary flatbed scanner, and the RGB information from before and after sample exposure was extracted using appropriate software. The color changes related to each spot were used to build differential maps with a unique fingerprint for each drug. The chemometric tools (i.e. PCA and HCA) showed suitable discrimination of all studied alkaloids in different quantities. To demonstrate a practical application, different alcoholic beverages spiked with scopolamine - a famous substance that causes drug abuse - were analyzed using the optoelectronic tongue. The results showed that small quantities of the drug were identified in different beverages, demonstrating that our device has the potential to be used in situ to prevent ingestion of contaminated samples.Acute lung injury (ALI) is a pulmonary inflammatory disease with high morbidity and mortality rates. However, owing to the unknown etiology and rapid progression of the disease, the diagnosis of ALI is full of challenges with no effective treatment. Since the inflammatory response and oxidative stress played vital roles in the development of ALI, we herein developed the largest emission cross-shift (△λ = 145 nm) two-photon ratiometric fluorescent probe of TPRS-HOCl with high selectivity and short response time toward hypochlorous acid (HOCl) for exploring the relevance between the degree of ALI and HOCl concentration in the development process of the disease. In addition, the inhibition effect of HOCl during different treatment periods was also evaluated. Moreover, the tendency of imaging results was basically in accordance with that of hematoxylin and eosin (H&E) staining and the treatment effect became better in the early stage when using N-acetylcysteine (NAC), demonstrating the sensitivity of TPRS-HOCl toward ALI response. Thus, TPRS-HOCl has great potential to diagnose ALI in the early stage and guide for effective treatment.Here, a primer-template conversion-based cascade signal amplification strategy is described for the sensitive detection of polynucleotide kinase (PNK) activity. This strategy integrated rolling circle amplification (RCA) and multiple-repeated-strand displacement amplification (MRSDA) with G-quadruplex based fluorescence lighting-up assay. A delicate dumbbell-shaped DNA probe with 5'-hydroxyl terminus was designed, in which G-quadruplex and half recognition site of nicking enzyme Nb.BbvCI were encoded in two loops respectively. Under the action of PNK, the 5' terminus on dumbbell probe was firstly phosphorylated, and then the dumbbell was cyclized with the catalyzation of T4 ligase to become the RCA template. The RCA process produced multiple copies of the prolonged primer. After that, under the assistance of nicking enzyme Nb.BbvCI, a primer-template conversion occurred, which converted the primer and template of RCA into the template and primer of the subsequent MRSDA, respectively. The MRSDA generated multiple repeated ssDNA sequences which possessed G-quadruplexes for outputting signal by lighting-up fluorescence of thioflavin T (ThT). The cascade signal amplification of RCA and MRSDA provided high detection sensitivity, and the target-dependence of template in cascade signal amplification led to a low background. The method showed excellent detection limit of 0.2 × 10-6 U μL-1 in buffer and 5 cells in cell lysate sample. Moreover, this method displayed favorable selectivity when interfering proteins were present. The developed strategy has good practical potential for PNK activity detection in clinical diagnosis and medical research.Rapid and sensitive detection of tumor biomarkers and cancer cells is of crucial importance for the early diagnosis and prognosis prediction of cancer. The present report describes a target-induced fluorescence enhancement immunosensor that utilizes the optical property of carbon dots (CDs) and the metal-enhanced fluorescence effect (MEF) property of silver nanoparticles (AgNPs) for the sensitive detection of the cancer biomarker human epididymis protein 4 (HE4) and ovarian cancer cells. Nitrogen and sulfur co-doped CDs with a quantum yield of 85.6% were prepared and served as the fluorophore in MEF. The HE4 antibody (Ab) specific to the HE4 antigen was linked covalently to the surface of the synthesized CDs as the capture. The HE4 Ab-conjugated AgNPs (AgNPs-Ab) were prepared and utilized as signal amplification elements. In the presence of the target HE4, composite sandwich structures were formed between the labeled CDs-Ab and AgNPs-Ab, which brought the CDs and AgNPs into proximity, resulting in the fluorescence of CDs enhancement owing to MEF. The intensity of fluorescence enhancement was positively correlated with the HE4 concentration in the clinically important range of 0.01-200 nM with a limit detection of 2.3 pM. Moreover, the immunosensor was also successfully applied to specific fluorescence labeling and quantitative determination of HE4-positive ovarian cancer cells. The proposed target-triggered MEF sensor platform demonstrated high sensitivity, excellent anti-interference ability, along with successful validation in complex biological matrices, providing a new approach for HE4 detection in early diagnosis and therapeutic monitoring.The Theory of Sampling as developed by Pierre Gy is a complete theory that describes sampling errors and how to obtain a representative sample. Unfortunately Gy's formula for prediction of the Fundamental Sampling Error (FSE) can be difficult to use in practice, as it is only valid for binary materials with same size distribution of analyte containing fragments and matrix fragments. An extended Gy's formula for estimation of FSE is derived from Gy's definition of constitutional heterogeneity. This formula is exact with no assumptions and allows prediction of FSE for any particulate material with any number of particle classes in contrast to Gy's formula. The difference is that the only assumption made is that the sampled material can be divided into classes with similar properties for the fragments within each class. The extended Gy's formula is validated by model experiments sampling mixtures of 3-7 components with a riffle splitter with 18 chutes. In most cases the observed sampling error was well predicted by the newly derived, extended Gy's formula.
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