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1.
Clin Chim Acta ; 560: 119731, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38754576

RESUMO

BACKGROUND: The viral load (VL) in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-infected individuals is critical for improving clinical treatment strategies, care, and decisions. Several studies have reported that the initial SARS-CoV-2 VL is associated with disease severity and mortality. Cycle threshold (Ct) values and/or copies/mL are often used to quantify VL. However, a multitude of platforms, primer/probe sets of different SARS-CoV-2 target genes, and reference material manufacturers may cause inconsistent interlaboratory interpretations. The first International Standard for SARS-CoV-2 RNA quantitative assays has allowed diagnostic laboratories to transition SARS-CoV-2 VL results into international units per milliliter (IU/mL). The Cobas SARS-CoV-2 Duo quantitative assay provides VL results expressed in IU/mL. MATERIALS AND METHODS: We enrolled 145 and 50 SARS-CoV-2-positive, hospitalized and 50-negative individuals at the Tri-Service General Hospital, Taiwan from January to May 2022. Each participant's electronic medical record was reviewed to determine asymptomatic, mild, moderate, and severe cases. Nasopharyngeal swabs were collected using universal transport medium. We investigated the association of SARS-CoV-2 VL with disease severity using the Cobas SARS-CoV-2 Duo quantitative assay and its functionality in clinical assessment and decision making to further improve clinical treatment strategies. Limit of detection (LOD) was assessed. RESULTS: All 50 SARS-CoV-2-negative samples confirmed negative for SARS-CoV-2, demonstrating 100 % specificity of the Cobas SARS-CoV-2 Duo assay. Patients with severe symptoms had longer hospital stays, and the length of hospital stay (30.56 days on average) positively correlated with the VL (8.22 ± 1.21 log10 IU/mL). Asymptomatic patients had the lowest VL (5.54 ± 2.06 log10 IU/mL) at admission and the shortest hospital stay (14.1 days on average). CONCLUSIONS: VL is associated with disease severity and duration of hospitalization; therefore, its quantification should be considered when making clinical care decisions and treatment strategies. The Cobas SARS-CoV-2 Duo assay provides a commutable unitage IU/mL for interlaboratory interpretations.

2.
Talanta ; 276: 126238, 2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38761655

RESUMO

Facing with the difficulty of specific chromatographic separation of nucleoside drugs, this study prepared a surface molecularly imprinted polymer (SMIP) modified covalent organic framework (COF) coated silica stationary phase based on the specificity of molecular imprinting technology and the powerful chromatographic separation performance of COF. This novel SMIP-COF@SiO2 stationary phase can not only specifically identify template molecule and structural analogs, but can also be used to separate multiple types of analytes, such as B vitamins, sulfonamides, alkylbenzenes, phenyl ketones, polycyclic aromatic hydrocarbons and environmental endocrine disruptors, which satisfies the need for complex sample separation. Various retention mechanisms have been investigated and multiple interactions between the SMIP-COF@SiO2 stationary phase and the analytes are discovered. The chromatographic performance of SMIP-COF@SiO2 is far superior to that of the SMIP@SiO2 and COF@SiO2. Furthermore, the SMIP-COF@SiO2 stationary phase can be successfully used to analyze polycyclic aromatic hydrocarbons in the environmental water sample and detect whitening ingredient in skincare product, indicating its great potential for application in various fields.

3.
Psychiatry Res ; 335: 115886, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38574699

RESUMO

We aim to systematically review and meta-analyze the effectiveness and safety of psychedelics [psilocybin, ayahuasca (active component DMT), LSD and MDMA] in treating symptoms of various mental disorders. Web of Science, Embase, EBSCO, and PubMed were searched up to February 2024 and 126 articles were finally included. Results showed that psilocybin has the largest number of articles on treating mood disorders (N = 28), followed by ayahuasca (N = 7) and LSD (N = 6). Overall, psychedelics have therapeutic effects on mental disorders such as depression and anxiety. Specifically, psilocybin (Hedges' g = -1.49, 95% CI [-1.67, -1.30]) showed the strongest therapeutic effect among four psychedelics, followed by ayahuasca (Hedges' g = -1.34, 95% CI [-1.86, -0.82]), MDMA (Hedges' g = -0.83, 95% CI [-1.33, -0.32]), and LSD (Hedges' g = -0.65, 95% CI [-1.03, -0.27]). A small amount of evidence also supports psychedelics improving tobacco addiction, eating disorders, sleep disorders, borderline personality disorder, obsessive-compulsive disorder, and body dysmorphic disorder. The most common adverse event with psychedelics was headache. Nearly a third of the articles reported that no participants reported lasting adverse effects. Our analyses suggest that psychedelics reduce negative mood, and have potential efficacy in other mental disorders, such as substance-use disorders and PTSD.


Assuntos
Alucinógenos , Transtornos Mentais , N-Metil-3,4-Metilenodioxianfetamina , Transtorno Obsessivo-Compulsivo , Humanos , Alucinógenos/efeitos adversos , Psilocibina/efeitos adversos , N-Metil-3,4-Metilenodioxianfetamina/uso terapêutico , Dietilamida do Ácido Lisérgico/efeitos adversos , Transtornos Mentais/tratamento farmacológico , Transtornos Mentais/induzido quimicamente , Transtorno Obsessivo-Compulsivo/tratamento farmacológico
4.
J Chromatogr A ; 1722: 464867, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38598895

RESUMO

Hydrogels with a unique three-dimensional network structure have been widely used in a variety of fields. However, hydrogels are prone to swelling under water-rich conditions, which severely limits their application in liquid chromatography. Therefore, producing a hydrogel with reliable performance and good mechanical property is essential. Smart temperature-sensitive chromatographic packings have attracted extensive attentions in recent years. In this work, sodium 4-styrenesulfonate and 1-octadecene were introduced into the poly(N-isopropylacrylamide) hydrogel to improve mechanical property and separation performance. As a consequence, a smart temperature-sensitive terpolymeric hydrogel modified silica stationary phase (ION-hydrogel@SiO2) was synthesized for multimode liquid chromatographic separation. It was found that this new ION-hydrogel@SiO2 column exhibited excellent chromatographic separation ability for a wide range of analytes. To a certain extent, this new column has a higher chromatographic separation efficiency compared to the commercial C18 column and XAmide column. Moreover, the use of low proportion of organic phase in chromatographic separation is conducive to the realization of green chromatography. By investigating the chromatographic separation mechanism, it has been demonstrated that the hydrogen bonding interaction is primarily responsible for the temperature-sensitive behavior of the hydrogel. Finally, the ION-hydrogel@SiO2 column was used for the determination of pyridoxine in the commercially available tablet samples. In conclusion, this study presents a feasible idea for the development of novel copolymer hydrogels as liquid chromatographic stationary phases.


Assuntos
Resinas Acrílicas , Hidrogéis , Dióxido de Silício , Temperatura , Hidrogéis/química , Cromatografia Líquida/métodos , Dióxido de Silício/química , Resinas Acrílicas/química , Polímeros/química , Ligação de Hidrogênio
5.
Int J Biol Macromol ; 269(Pt 1): 131798, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38677689

RESUMO

Citrus fiber, a by-product of citrus processing that has significant nutritional and bioactive properties, has gained attention as a promising raw material with extensive developmental potential in the food, pharmaceutical, and feed industries. However, the lack of in-depth understanding regarding citrus fiber, including its structure, modification, mechanism of action, and potential applications is holding back its development and utilization in functional foods and drugs. This review explores the status of extraction methods and modifications applied to citrus fiber to augment its health benefits. With the aim of introducing readers to the potential health benefits of citrus fibers, we have placed special emphasis on their regulatory mechanisms in the context of various conditions, including type 2 diabetes mellitus, cardiovascular disease, obesity, and cancer. Furthermore, this review highlights the applications and prospects of citrus fiber, aiming to provide a theoretical basis for the utilization and exploration of this valuable resource.

6.
Chem Commun (Camb) ; 60(37): 4918-4921, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38628069

RESUMO

To avoid the unexpected aggregation and reduce the cytotoxicity of nanomaterials as optical probes in cell imaging applications, we propose a programmed DNA-cube as a carrier for silver nanoparticles (Ag NPs) to construct a specific hydrogen sulfide (H2S) responsive platform (Ag NP@DNA-cube) for diagnosing colorectal cancer (CRC) in this study. The DNA-cube maintains good dispersion of Ag NPs while providing excellent biocompatibility. Based on the characteristic overexpression of endogenous H2S in CRC cells, the Ag NPs are etched by H2S within target cells into silver sulfide quantum dots, thereby selectively illuminating the target cells. The Ag NP@DNA-cube exhibits a specific fluorescence response to CRC cells and achieves satisfactory imaging.


Assuntos
Neoplasias Colorretais , DNA , Sulfeto de Hidrogênio , Nanopartículas Metálicas , Prata , Sulfeto de Hidrogênio/análise , Sulfeto de Hidrogênio/química , Humanos , Nanopartículas Metálicas/química , Neoplasias Colorretais/patologia , Prata/química , DNA/química , Imagem Óptica , Pontos Quânticos/química , Linhagem Celular Tumoral
7.
Anal Chim Acta ; 1299: 342445, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38499423

RESUMO

BACKGROUND: Due to their excellent stability, low toxicity, flexible modification and adjustable functionality, carbon dots (CDs) have a promising application prospect in the field of chromatographic stationary phases. Hydrogels are new functional polymer materials with three-dimensional network structure that have excellent hydrophilicity, high porosity and unique mechanical properties, which are also good candidate materials for liquid chromatography. Nevertheless, a review of the literature reveals that CDs based nanocomposite hydrogels have not yet been reported as HPLC stationary phases. RESULTS: In this work, amphiphilic CDs with multiple functional groups and polyacrylic acid hydrogel were grafted to the surface of silica gel by an in-situ polymerization method, and a CDs/polyacrylic acid nanocomposite hydrogel stationary phase (CDs/hydrogel@SiO2) was prepared. CDs act as the macroscopic cross-linking agents to form a cross-linked network with polyacrylic acid chains through physical cross-linking by hydrogen bonding and chemical cross-linking by amidation and esterification reactions, which not only improve the swelling property of the hydrogel but also increase its stability. Additionally, the introduction of CDs with multifunctional groups modulates the hydrophilic-hydrophobic balance of the hydrogel that also imparts good hydrophobicity to the composite hydrogel. Through the study of retention mechanism and influencing factors, it is certificate that the CDs/hydrogel@SiO2 has mixed-mode chromatographic performance. Furthermore, the CDs/hydrogel@SiO2 column shows great potential for the determination of organic contaminants in environmental water samples. SIGNIFICANCE: This work confirms the potential application of CDs/hydrogel composite for the separation of various samples and provides the possibility of developing CDs based nanocomposite hydrogel in the field of liquid chromatography. Introducing CDs into hydrogel can open up a new way for nanocomposite hydrogels to be used in HPLC, which expands the advance of hydrogel and CDs in separation field.

8.
Talanta ; 272: 125838, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38430866

RESUMO

In this study, a novel integrated liposome-based microfluidic platform combined with a smartphone was designed for the rapid colorimetric detection of microRNA-21 (miRNA-21) in real samples. The flowing surface-functionalized liposomes were first captured by nucleic acid-functionalized Au nanoparticles in the microfluidic chip. In the presence of miRNA-21, the DNA strand modified on the surface of Au nanoparticles hybridized with the target to form double-stranded products and was cleaved by duplex-specific nuclease (DSN) enzyme, causing the liposomes to be re-released. Then, as the liposomes in the colorimetric module were lysed and the "cellular" contents were released, a step-by-step "glucose-glucose oxidase-3,3',5,5'-tetramethylbenzidine (TMB)" colorimetric reaction process catalyzed by the G-quadruplex/hemin was triggered. The grayscale values were recorded and recognized by the smartphone camera for miRNA-21 analysis. The advantages of the present strategy included the portability of smartphone-based colorimetric assay, the encapsulation and transport of reactants by liposomes and the low solvent usage of microfluidic chip. Under optimal conditions, this assay exhibited a wide linear range from 1 pM to 1 nM (r2 = 0.9981), and the limit of detection of miRNA-21 was as low as 0.27 pM. Moreover, the high specificity of this strategy allowed its successful application to the rapid analysis of miRNA-21 in real blood serum samples of people with type 2 diabetes.


Assuntos
Técnicas Biossensoriais , Diabetes Mellitus Tipo 2 , Nanopartículas Metálicas , MicroRNAs , Humanos , MicroRNAs/análise , Lipossomos , Colorimetria , Microfluídica , Ouro , Limite de Detecção
9.
J Mater Chem C Mater ; 12(12): 4369-4383, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38525159

RESUMO

Fluorescence bioimaging with near-infrared II (NIR-II) emissive organic fluorophores has proven to be a viable noninvasive diagnostic technique. However, there is still the need for the development of fluorophores that possess increased stability as well as functionalities that impart stimuli responsiveness. Through strategic design, we can synthesize fluorophores that possess not only NIR-II optical profiles but also pH-sensitivity and the ability to generate heat upon irradiation. In this work, we employ a donor-acceptor-donor (D-A-D) design to synthesize a series of NIR-II fluorophores. Here we use thienothiadiazole (TTD) as the acceptor, 3-hexylthiophene (HexT) as the π-spacer and vary the alkyl amine donor units: N,N-dimethylaniline (DMA), phenylpiperidine (Pip), and phenylmorpholine (Morp). Spectroscopic analysis shows that all three derivatives exhibit emission in the NIR-II region with λemimax ranging from 1030 to 1075 nm. Upon irradiation, the fluorophores exhibited noticeable heat generation through non-radiative processes. The ability to generate heat indicates that these fluorophores will act as theranostic (combination therapeutic and diagnostic) agents in which simultaneous visualization and treatment can be performed. Additionally, biosensing capabilities were supported by changes in the absorbance properties while under acidic conditions as a result of protonation of the alkyl amine donor units. The fluorophores also show minimal toxicity in a human mammary cell line and with murine red blood cells. Overall, initial results indicate viable NIR-II materials for multiple biomedical applications.

10.
Anal Chem ; 96(13): 5195-5204, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38520334

RESUMO

The detection of multiple single nucleotide polymorphisms (SNPs) of circulating tumor DNA (ctDNA) is still a great challenge. In this study, we designed enzyme-assisted nucleic acid strand displacement amplification combined with high-performance liquid chromatography (HPLC) for the simultaneous detection of three ctDNA SNPs. First, the trace ctDNA could be hybridized to the specially designed template strand, which initiated the strand displacement nucleic acid amplification process under the synergistic action of DNA polymerase and restriction endonuclease. Then, the targets would be replaced with G-quadruplex fluorescent probes with different tail lengths. Finally, the HPLC-fluorescence assay enabled the separation and quantification of multiple signals. Notably, this method can simultaneously detect both the wild type (WT) and mutant type (MT) of multiple ctDNA SNPs. Within a linear range of 0.1 fM-0.1 nM, the detection limits of BRAF V600E-WT, EGFR T790M-WT, and KRAS 134A-WT and BRAF V600E-MT, EGFR T790M-MT, and KRAS 134A-MT were 29, 31, and 11 aM and 22, 29, and 33 aM, respectively. By using this method, the mutation rates of multiple ctDNA SNPs in blood samples from patients with lung or breast cancer can be obtained in a simple way, providing a convenient and highly sensitive analytical assay for the early screening and monitoring of lung cancer.


Assuntos
DNA Tumoral Circulante , Neoplasias Pulmonares , Humanos , DNA Tumoral Circulante/genética , Mutação , Polimorfismo de Nucleotídeo Único , Proteínas Proto-Oncogênicas B-raf/genética , Receptores ErbB/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , Inibidores de Proteínas Quinases , Cromatografia Líquida
11.
World Neurosurg ; 185: e431-e441, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38360209

RESUMO

OBJECTIVE: To investigate the influence of sacroiliac interosseous ligament tension and laxity on the biomechanics of the lumbar spine. METHODS: A static analysis of a three-dimensional finite element model of the Lumbar-Pelvic is conducted to verify the model's effectiveness. Adjusting the sacroiliac ligament's elasticity modulus under a 10Nm lumbar flexion/extension moment, it simulates ligament tension/laxity to calculate vertebrae displacements, intervertebral disc stress and deformation, nucleus pulposus pressure, facet joint force, and ligament stress. RESULTS: With the elastic modulus of the sacroiliac ligament changing by +50%, -50%, and -90%, the angular displacement of vertebra 3 in forward flexion changes by +1.64%, -4.84%, and -42.3%, and the line displacements change by +5.7%, -16.4%, and -144.9%, respectively; and the angular displacements in backward extension change by +0.2%, -0.6%, -5.9% and the line displacements change by +5.5%, -14.3%, and -125.8%. However, the angular displacement and center distance between adjacent vertebrae do not change, leading to no change in the maximum stress of the intervertebral disc and the maximum pressure in the nucleus pulposus. Flexion and extension directly affect the deformation and stress magnitude and distribution in the lumbar spine. CONCLUSIONS: While sacroiliac interosseous ligament laxity and tension have little effect on disc deformation and stress, and nucleus pulposus pressure, they reduce the stability of the lumbar-sacral vertebrae. In a forward flexion state, the lumbar ligaments bear a large load and are prone to laxity, thereby increasing the risk of lumbar injury.


Assuntos
Análise de Elementos Finitos , Ligamentos Articulares , Vértebras Lombares , Articulação Sacroilíaca , Humanos , Fenômenos Biomecânicos/fisiologia , Articulação Sacroilíaca/fisiopatologia , Ligamentos Articulares/fisiopatologia , Ligamentos Articulares/fisiologia , Amplitude de Movimento Articular/fisiologia , Instabilidade Articular/fisiopatologia , Módulo de Elasticidade , Estresse Mecânico
12.
Skeletal Radiol ; 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38411702

RESUMO

For Caucasian women, the QCT (quantitative CT) lumbar spine (LS) bone mineral density (BMD) cutpoint value for classifying osteoporosis is 80 mg/ml. At the age of approximate 78 years, US Caucasian women QCT LS BMD population mean is 80 mg/ml, while that of Chinese women and Japanese women is around 50 mg/ml. Correlation analyses show, for Chinese women and Japanese women, QCT LS BMD of 45 mg/ml corresponds to the dual-energy X-ray absorptiometry cutpoint value for classifying osteoporosis. For Chinese and Japanese women, if QCT LS BMD 80 mg/ml is used as the threshold to classify osteoporosis, then the specificity of classifying subjects with vertebral fragility fracture into the osteoporotic group is low, whereas threshold of 45 mg/ml approximately achieve a similar separation for women with and without vertebral fragility fracture as the reports for Caucasian women. Moreover, by using 80mg/ml as the cutpoint value, LS QCT leads to excessively high prevalence of osteoporosis for Chinese women, with the discordance between hip dual-energy X-ray absorptiometry and LS QCT measures far exceeding expectation. Considering the different bone properties and the much lower prevalence of fragility fractures in the East Asian women compared with Caucasians, we argue that the QCT cutpoint value for classifying osteoporosis among older East Asian women will be close to and no more than 50 mg/ml LS BMD. We suggest that it is also imperative the QCT osteoporosis classification criterion for East Asian male LS, and male and female hips be re-examined.

13.
Foods ; 13(4)2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38397553

RESUMO

Naringin is one of the common flavonoids in grapefruit, which has anti-cancer, antioxidant, and anti-inflammatory activities. However, its poor solubility limits its wide application. Therefore, the aim of this study is to investigate the anti-inflammatory effect of naringin combined with chitooligosaccharides with good biocompatibility by constructing a mouse model of systemic inflammatory response syndrome (SIRS). The results showed that the naringin-chitooligosaccharide (NG-COS) complex significantly inhibited lipopolysaccharide (LPS)-induced weight loss, reduced food intake, tissue inflammatory infiltration, and proinflammatory cytokines IL-6, TNF-α, INF-γ, and IL-1ß levels. The complex also significantly affected the content of malondialdehyde and the activities of MPO, SOD, and GSH in the liver, spleen, lungs, and serum of mice with systemic inflammation. In addition, NG-COS significantly inhibited the mRNA expression of inflammatory factors in the TLR4/NF-κB signaling pathway. Principal component analysis showed that the complexes could inhibit LPS-induced systemic inflammation in mice, and the effect was significantly better than that of naringin and chitooligosaccharides alone. This study explored the synergistic effects of chitosan and naringin in reducing inflammation and could contribute to the development of novel biomedical interventions.

14.
Chem Commun (Camb) ; 60(19): 2669-2672, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38351890

RESUMO

Reported herein is a photochemical strategy for C(sp3)-H azolation of ethers via a hydrogen-atom transfer and radical-polar crossover process, offering efficient access to valuable N-alkylated azoles under visible-light irradiation. The protocol is metal-free and photocatalyst-free, and exhibits good to excellent yields and broad substrate scope with regard to azoles. EPR experiments provide evidence for the formation of intermediates formed in situ.

15.
Anal Chem ; 96(3): 1054-1063, 2024 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-38190445

RESUMO

In this work, an integrated strategy with excellent accuracy and high throughput is proposed for the precise indication of single nucleotide polymorphism (SNP) in nonsmall cell lung cancer diseases. Two types of point mutations (L858R and T790M) and the corresponding wild types could be identified together in a single high-performance liquid chromatographic run. Signal amplification was achieved through a series of enzyme ligation, primer extension, and enzyme cleavage strategies, and a large number of DNA probes with different fluorescence signals were finally generated. The factors affecting the spatiotemporal separation efficiency of four DNA probes were systematically investigated. The limits of detection of wild types (WTs) or mutant types (MTs) abbreviated as L858R-MT, L858R-WT, T790M-MT, and T790M-WT were 26, 24, 19, and 22 aM, respectively. In addition, the levels of mutant types and wild types in the serum of 40 nonsmall cell lung cancer patients at different stages were detected using the method, and the correlation between the mutation ratios and cancer stages was preliminarily verified. The proposed highly selective and sensitive method may serve as an alternative approach for early diagnosis and staging of nonsmall cell lung cancer.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/genética , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , Receptores ErbB/metabolismo , Polimorfismo de Nucleotídeo Único , Mutação , Inibidores de Proteínas Quinases , Cromatografia Líquida , Sondas de DNA
16.
Food Chem ; 442: 138505, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38266408

RESUMO

Streptomycin (STR), an aminoglycoside antibiotic with the potential to persist in honey and other food products, may induce allergy, toxicity and antibiotic resistance in humans. In this study, we developed a solid-phase microextraction (SPME) biosensor based on a quartz rod that was modified with double-stranded DNA structures consisting of partially complementary G-rich base DNA strand and STR aptamer. The STR isolated by SPME initially bound to the aptamer. Then the remaining double-stranded DNA structures were cleaved by the Nt.BstNBI enzyme, resulting in release of G-quadruplex dimers. The latter formed a complex with thioflain T fluorescent dye, resulting in an amplified fluorescence response. The method exhibited high sensitivity (a limit of detection of 10.84 pM), wide linear range (0.05 nM âˆ¼ 500 nM (with determination coefficient > 0.99)), and simple operation, making it suitable and convenient for STR detection. Successful STR determination in genuine honey samples was demonstrated.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Mel , Humanos , Estreptomicina , Mel/análise , Microextração em Fase Sólida/métodos , DNA , Aptâmeros de Nucleotídeos/química , DNA Complementar , Técnicas Biossensoriais/métodos , Limite de Detecção
17.
Org Lett ; 26(1): 304-309, 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38165162

RESUMO

Reported herein is direct C(sp3)-H arylation of unprotected benzyl anilines and alkylarenes via consecutive photoinduced electron transfer by visible light irradiation. Reductive quenching cycles and radical-radical cross-coupling were involved, and electron paramagnetic resonance experiments provide evidence for the formation of radical intermediates formed in situ. The protocol highlights transition metal free, external oxidant free, broad substrate scope, and high efficiency (>60 examples, up to 96%).

18.
J Asian Nat Prod Res ; : 1-8, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38234138

RESUMO

An anti-neuroinflammatory activities-guided phytochemical research of Wikstroemia lungtzeensis was performed for the first time. Three undescribed carotane-type sesquiterpenes, excoecafolinols C-E (1-3), and nine known sesquiterpene derivatives were isolated from the effective ethyl acetate extract of W. lungtzeensis. Their structures were determined based on multiple spectroscopic techniques and electronic circular dichroism (ECD) spectra. Furthermore, the anti-neuroinflammatory activities of the identified compounds were evaluated in lipopolysaccharide-stimulated BV-2 cells. Among them, six components (1, 2, 4, 7, 11, 12) exhibited significant inhibitory effects on nitric oxide (NO) production, with IC50 values ranging from 10.48 to 49.41 µM (positive control minocycline, IC50 53.20 µM). Carotane-type sesquiterpenes (1, 2, 4) with high content and significant inhibitory effects, are considered to be major active ingredients of W. lungtzeensis, which might serve as potential therapeutic agents for neurodegenerative diseases.

19.
Artigo em Inglês | MEDLINE | ID: mdl-38235712

RESUMO

The study aimed to investigate the dynamic characteristics of the cervical spine and determine the effect of the material properties of the cervical spinal components on it. A finite element model of the head-cervical spine was developed based on CT scan data, and the first six orders of modes (e.g. flexion-extension, lateral bending, and vertical, etc.) were verified by experimental and simulation studies. The material sensitivity study was conducted by varying elasticity modulus of cervical hard tissues (cortical bone, cancellous bone, endplates, and posterior elements) and soft tissues (intervertebral disc and ligaments). The results showed that increasing the elastic modulus of ligaments by 4 times increased the natural frequency by 77%, while increasing that of cancellous bone by 4 times only increased the natural frequency by 6%. In the axial mode, the cervical spine had not only axial deformation but also anterior-posterior deformation, with the largest deformation located at the intervertebral disc C6-C7. Decreasing the elastic modulus of a component in soft tissues by 80% increased modal displacement by up to 62%. The material properties of the intervertebral discs and ligaments had opposite effects on the modal displacement and deformation of the cervical spine. Low cervical discs were more susceptible to injury in a vertical vibration environment. Cervical spine dynamics were more sensitive to soft tissue material properties than to hard tissue material properties. Disc degeneration could reduce the range of vibratory motion of the cervical spine, thereby reducing the ability of the cervical spine to cushion head impacts.

20.
Quant Imaging Med Surg ; 14(1): 1010-1021, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38223080

RESUMO

Background: Pulmonary nodular consolidation (PN) and pulmonary cavity (PC) may represent the two most promising imaging signs in differentiating multidrug-resistant (MDR)-pulmonary tuberculosis (PTB) from drug-sensitive (DS)-PTB. However, there have been concerns that literature described radiological feature differences between DS-PTB and MDR-PTB were confounded by that MDR-PTB cases tend to have a longer history. This study seeks to further clarify this point. Methods: All cases were from the Guangzhou Chest Hospital, Guangzhou, China. We retrieved data of consecutive new MDR cases [n=46, inclusive of rifampicin-resistant (RR) cases] treated during the period of July 2020 and December 2021, and according to the electronic case archiving system records, the main PTB-related symptoms/signs history was ≤3 months till the first computed tomography (CT) scan in Guangzhou Chest Hospital was taken. To pair the MDR-PTB cases with assumed equal disease history length, we additionally retrieved data of 46 cases of DS-PTB patients. Twenty-two of the DS patients and 30 of the MDR patients were from rural communities. The first CT in Guangzhou Chest Hospital was analysed in this study. When the CT was taken, most cases had anti-TB drug treatment for less than 2 weeks, and none had been treated for more than 3 weeks. Results: Apparent CT signs associated with chronicity were noted in 10 cases in the DS group (10/46) and 9 cases in the MDR group (10/46). Thus, the overall disease history would have been longer than the assumed <3 months. Still, the history length difference between DS patients and MDR patients in the current study might not be substantial. The lung volume involvement was 11.3%±8.3% for DS cases and 8.4%±6.6% for MDR cases (P=0.022). There was no statistical difference between DS cases and MDR cases both in PN prevalence and in PC prevalence. For positive cases, MDR cases had more PN number (mean of positive cases: 2.63 vs. 2.28, P=0.38) and PC number (mean of positive cases: 2.14 vs. 1.38, P=0.001) than DS cases. Receiver operating characteristic curve analysis shows, PN ≥4 and PC ≥3 had a specificity of 86% (sensitivity 25%) and 93% (sensitivity 36%), respectively, in suggesting the patient being a MDR cases. Conclusions: A combination of PN and PC features allows statistical separation of DS and MDR cases.

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