Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 3.170
Filtrar
1.
Mikrochim Acta ; 191(4): 185, 2024 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-38451330

RESUMO

A dual-mode sensor was developed for detecting acetylcholinesterase (AChE) and organophosphorus pesticides (OPs) via bifunctional BSA-CeO2 nanoclusters (NCs) with oxidase-mimetic activity and fluorescence property. The dual-mode sensor has the characteristics of self-calibration and self-verification, meeting the needs of different detection conditions and provide more accurate results. The colorimetric sensor and fluorescence sensor have been successfully used for detecting AChE with limit of detection (LOD) of 0.081 mU/mL and 0.056 mU/mL, respectively, while the LOD for OPs were 0.9 ng/mL and 0.78 ng/mL, respectively. The recovery of AChE was 93.9-107.2% and of OPs was 95.8-105.0% in actual samples. A novel strategy was developed to monitor pesticide residues and detect AChE level, which will motivate future work to explore the potential applications of multifunctional nanozymes.


Assuntos
Acetilcolinesterase , Técnicas de Química Analítica , Praguicidas , Smartphone , Acetilcolinesterase/análise , Hidrogéis , Compostos Organofosforados , Praguicidas/efeitos adversos , Técnicas de Química Analítica/métodos
2.
Chem Commun (Camb) ; 60(8): 996-999, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38168820

RESUMO

Although some simple and rapid colorimetric methods have been developed to detect organophosphorus pesticides (OPs), the difficult extraction and easy denaturation of acetylcholinesterase (AChE) are still drawbacks needing to be overcome. Here, we propose a MOF nanozyme-mediated AChE-free colorimetric strategy for the direct detection of OPs. In the presence of OPs (pirimiphos-methyl as a model), the intense blue of oxidized 3,3',5,5'-tetramethylbenzidine (TMB) becomes light due to the quenching effect of OPs towards hydroxyl radicals (˙OH) that are generated by the decomposition of H2O2 catalyzed by the Cu4Co6 ZIF nanozyme with excellent peroxidase (POD)-like activity. The developed colorimetric sensor exhibits assay performance and offers a universal and promising analysis strategy for detecting OPs in practical samples.


Assuntos
Técnicas Biossensoriais , Praguicidas , Praguicidas/análise , Acetilcolinesterase/análise , Compostos Organofosforados/análise , Colorimetria/métodos , Peróxido de Hidrogênio , Técnicas Biossensoriais/métodos
3.
Nat Prod Res ; 38(6): 994-1001, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37157866

RESUMO

Phytochemical study on the rhizomes of Kaempferia parviflora led to the isolation of twenty-three compounds including six phenolic glycosides (1-6), thirteen flavones (7-19), and five phenolic compounds (20-23). Of these, the new compounds were determined to be 2,4-dihydroxy-6-methoxyacetophenone-2-ß-D-apiofuranosyl-(1→6)-ß-D-glucopyranoside (1), 2-hydroxy-4-propionyl-phenyl O-ß-D-glucopyranoside (2), and 4-hydroxy-3,5-dimethoxyacetophenone 8-O-α-L-rhamnopyranosyl-(1→6)-ß-D-glucopyranoside (3) and named as kaempanosides A-C, respectively. Their chemical structures were established based on HR-ESI-MS, 1D and 2D NMR spectra. All compounds 1-23 exhibited acetylcholinesterase inhibitory activity with IC50 values ranging from 57.76 to 253.31 µM.


Assuntos
Flavonas , Zingiberaceae , Acetilcolinesterase/análise , Rizoma/química , Flavonas/farmacologia , Extratos Vegetais/química , Glicosídeos/química , Zingiberaceae/química
4.
Fitoterapia ; 172: 105721, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37931718

RESUMO

Five new biflavonoids, diphybiflavonoids A - E (1-5), were isolated from the roots and rhizomes of Diphylleia sinensis. Their structures were elucidated by extensive spectroscopic data, including UV, IR, HR-ESI-MS and 2D NMR. Their absolute configurations were determined by ECD spectra. All isolated compounds were evaluated for acetylcholinesterase (AChE) inhibitory activity. Compounds 1-4 exhibited the potent AChE inhibitory activities with IC50 values of 1.62, 2.10, 2.08, and 5.15 µM, respectively. The preliminary structure-activity relationship study indicated that the connection mode (C2-O-C4'''/C3-O-C3''' or C2-O-C3'''/C3-O-C4''') of biflavonoid subunits, and 3-hydroxy group of flavonol subunit were important structural factors for AChE inhibitory activity. Biflavonoids, containing a C2-O-C4'''/C3-O-C3''' or C2-O-C3'''/C3-O-C4''' linkage, can be a potentially useful platform for development of cholinesterase inhibitors.


Assuntos
Berberidaceae , Biflavonoides , Biflavonoides/farmacologia , Estrutura Molecular , Acetilcolinesterase/análise , Acetilcolinesterase/metabolismo , Relação Estrutura-Atividade , Raízes de Plantas/química , Inibidores da Colinesterase/farmacologia , Inibidores da Colinesterase/química
5.
Malar J ; 22(1): 368, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38041142

RESUMO

BACKGROUND: Anopheles pharoensis has a major role in transmitting several human diseases, especially malaria, in Egypt?. Controlling Anopheles is considered as an effective strategy to eliminate the spread of malaria worldwide. Galaxaura rugosa is a species of red algae found in tropical to subtropical marine environments. The presence of G. rugosa is indicative of the ecosystem's overall health. The current work aims to investigate UPLC/ESI/MS profile of G. rugosa methanol and petroleum ether extracts and its activity against An. pharoensis and non-target organisms, Danio rerio and Daphnia magna. METHODS: Galaxaura rugosa specimens have been identified using DNA barcoding for the COI gene and verified as G. rugosa. The UPLC/ESI/MS profiling of G. rugosa collected from Egypt was described. The larvicidal and repellent activities of G. rugosa methanol and petroleum ether extracts against An. pharoensis were evaluated, as well as the toxicity of tested extracts on non-target organisms, Dan. rerio and Dap. magna. RESULTS: The UPLC/ESI/MS analysis of methanol and petroleum ether extracts led to the tentative identification of 57 compounds belonging to different phytochemical classes, including flavonoids, tannins, phenolic acids, phenyl propanoids. Larval mortality was recorded at 93.33% and 90.67% at 80 and 35 ppm of methanol and petroleum ether extracts, respectively, while pupal mortality recorded 44.44 and 22.48% at 35 and 30 ppm, respectively. Larval duration was recorded at 5.31 and 5.64 days by methanol and petroleum ether extracts at 80 and 35 ppm, respectively. A decrease in acetylcholinesterase (AChE) level and a promotion in Glutathione-S-transferase (GST) level of An. pharoensis 3rd instar larvae were recorded by tested extracts. The petroleum ether extract was more effective against An. pharoensis starved females than methanol extract. Also, tested extracts recorded LC50 of 1988.8, 1365.1, and 11.65, 14.36 µg/mL against Dan. rerio, and Dap. magna, respectively. CONCLUSIONS: Using red algae derivatives in An. pharoensis control could reduce costs and environmental impact and be harmless to humans and other non-target organisms.


Assuntos
Anopheles , Culex , Inseticidas , Malária , Rodófitas , Animais , Humanos , Peixe-Zebra , Daphnia , Biomarcadores Ambientais , Mosquitos Vetores , Metanol/análise , Metanol/farmacologia , Acetilcolinesterase/análise , Ecossistema , Extratos Vegetais/farmacologia , Solventes/análise , Solventes/farmacologia , Larva , Inseticidas/farmacologia , Folhas de Planta/química
6.
Anal Methods ; 15(30): 3700-3708, 2023 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-37470116

RESUMO

Acetylcholinesterase (AChE) plays a crucial role in biological neurotransmission. The aberrant expression of AChE is associated with various neurodegenerative diseases. Therefore, it is of great significance to develop a simple and highly sensitive AChE analysis platform. Herein, a simple colorimetric sensor was constructed for sensitive detection of AChE based on the peroxidase-like catalytic activity of Ni/Co layered double hydroxides (Ni/Co LDHs). In this sensor, the fabricated Ni/Co LDHs possess high peroxidase-like activity, enabling rapid catalysis of o-phenylenediamine (OPD) to produce yellow oxOPD in the presence of H2O2. This peroxidase-like activity of Ni/Co LDHs was found to be effectively inhibited by the presence of AChE. It is speculated that the combination of AChE on the outer surface of Ni/Co LDHs through non-covalent interaction may cover the active sites and hinder their adsorption to the substrates, leading to the failure of OPD oxidation. As a result, the yellow color from oxOPD is related to the AChE concentration, enabling the direct AChE assay in an equipment-free manner. In addition, the fabricated Ni/Co LDHs could be modified on a paper surface to obtain a paper-based analytical device for visualized colorimetric detection of AChE. The as-proposed sensor shows high sensitivity to AChE with a detection limit down to 6.6 µU mL-1. Therefore, this naked-eye paper-based sensor is capable of on-site and real-time detection of AChE, and has outstanding application prospects in clinical diagnosis and biomedical fields.


Assuntos
Acetilcolinesterase , Peróxido de Hidrogênio , Acetilcolinesterase/análise , Acetilcolinesterase/química , Acetilcolinesterase/metabolismo , Peróxido de Hidrogênio/química , Hidróxidos/química , Colorimetria , Antioxidantes , Peroxidases , Peroxidase
7.
Microsc Res Tech ; 86(10): 1363-1377, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37119431

RESUMO

Fabrication, characterization and evaluation of the larvicidal potential of novel silk protein (sericin)-based silver nanoparticles (Se-AgNPs) were the prime motives of the designed study. Furthermore, investigation of the sericin as natural reducing or stabilizing agent was another objective behind this study. Se-AgNPs were synthesized using sonication and heat. Fabricated Se-AgNPs were characterized using particle size analyzer, UV spectrophotometry, FTIR and SEM which confirmed the fabrication of the Se-AgNPs. Size of sonication-mediated Se-AgNPs was smaller (7.49 nm) than heat-assisted Se-AgNPs (53.6 nm). Being smallest in size, sonication-assisted Se-AgNPs revealed the significantly highest (F4,10 = 39.20, p = .00) larvicidal activity against fourth instar lab and field larvae (F4,10 = 1864, p = .00) of dengue vector (Aedes aegypti) followed by heat-assisted Se-AgNPs and positive control (temephos). Non-significant larvicidal activity was showed by silver (without sericin) which made the temperature stability of silver, debatable. Furthermore, findings of biochemical assays (glutathione-S transferase, esterase, and acetylcholinesterase) showed the levels of resistance in field strain larvae. Aforementioned findings of the study suggests the sonication as the best method for synthesis of Se-AgNPs while the larvicidal activity is inversely proportional to the size of Se-AgNPs, i.e., smallest the size, highest the larvicidal activity. Conclusively, status of the sericin as a natural reducing/stabilizing agent has been endorsed by the findings of this study. RESEARCH HIGHLIGHTS: Incorporation of biocompatible and inexpensive sericin as a capping/reducing agent for synthesis of Se-AgNPs. A novel sonication method was used for the fabrication of Se-AgNPs which were thoroughly characterized by particle size analyzer, UV-visible spectrophotometry, SEM and FTIR. Analysis of enzymatic (GSTs, ESTs) levels in field and lab strains of Aedes aegypti larvae for evaluation of insecticides resistance.


Assuntos
Aedes , Dengue , Inseticidas , Nanopartículas Metálicas , Sericinas , Animais , Nanopartículas Metálicas/química , Prata/farmacologia , Prata/química , Sericinas/farmacologia , Temperatura Alta , Acetilcolinesterase/análise , Acetilcolinesterase/metabolismo , Excipientes/análise , Excipientes/metabolismo , Sonicação , Extratos Vegetais/química , Mosquitos Vetores , Larva , Dengue/prevenção & controle , Dengue/metabolismo , Folhas de Planta/química
8.
Clinics (Sao Paulo) ; 78: 100198, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37075514

RESUMO

BACKGROUND: Hirschsprung's Disease (HD) is characterized by intestinal sub-occlusion and the absence of enteric ganglion cells. A rectal biopsy examination is performed to confirm the diagnosis. In a recent study, we demonstrated that the analysis of 60 sections of rectal mucosa and submucosa stained by H&E may ensure a 90% diagnostic accuracy. Although the need to analyze so many sections makes the process of reading the slides more time-consuming, this encouraged us to study their distribution in the healthy rectal submucosa, to simplify the diagnosis. OBJECTIVES: To develop a method that facilitates HD diagnosis by studying the distribution of ganglion cells in the submucosal plexus. METHODS: Using the calretinin technique, we studied the distribution of plexuses in 60 fragments of rectal submucosa from 19 cadavers. After the study, the reading method created was used for diagnosis in 47 cases of suspected HD, using H&E staining. The accuracy was verified by comparing the results obtained with H&E to those obtained with the acetylcholinesterase technique, the golden standard in our laboratory. RESULTS: The study of submucosal plexus distribution showed that just by examining the submucosal region every 20 µm, approximately, it is possible to locate a ganglionic plexus, and we have already been able to diagnose HD with 93% accuracy. CONCLUSION: The study of ganglion cell distribution enabled the creation of a simplified method for reading the slides. The method applied achieved good accuracy and it can be used as an alternative method in HD diagnosis.


Assuntos
Doença de Hirschsprung , Humanos , Lactente , Doença de Hirschsprung/diagnóstico , Doença de Hirschsprung/patologia , Acetilcolinesterase/análise , Reto/química , Reto/patologia , Biópsia/métodos
9.
Environ Res ; 227: 115724, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-36948285

RESUMO

Neurotoxic pesticides are a group of chemicals that pose a severe threat to both human health and the environment. These molecules are also known to accumulate in the food chain and persist in the environment, which can lead to long-term exposure and adverse effects on non-target organisms. The detrimental effects of these pesticides on neurotransmitter levels and function can lead to a range of neurological and behavioral symptoms, which are closely associated with neurodegenerative diseases. Hence, the accurate and reliable detection of these neurotoxic pesticides and associated neurotransmitters is essential for clinical applications, such as diagnosis and treatment. Over the past few decades, acetylcholinesterase (AchE) biosensors have emerged as a sensitive and reliable tool for the electrochemical detection of neurotoxic pesticides and acetylcholine. These biosensors can be tailored to utilize the high specificity and sensitivity of AchE, enabling the detection of these chemicals. Additionally, enzyme immobilization and the incorporation of nanoparticles have further improved the detection capabilities of these biosensors. AchE biosensors have shown tremendous potential in various fields, including environmental monitoring, clinical diagnosis, and pesticide residue analysis. This review summarizes the advancements in AchE biosensors for electrochemical detection of neurotoxic pesticides and acetylcholine over the past two decades.


Assuntos
Técnicas Biossensoriais , Resíduos de Praguicidas , Praguicidas , Humanos , Praguicidas/análise , Acetilcolinesterase/análise , Acetilcolinesterase/química , Acetilcolinesterase/metabolismo , Acetilcolina/análise , Resíduos de Praguicidas/análise
10.
J Tradit Chin Med ; 43(2): 252-264, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36994513

RESUMO

OBJECTIVE: To characterize the chemical profile of methanolic crude extract and its fractions (Ethyl acetate, n-butanol and aqueous) using liquid chromatography-mass spectrometry (LC-MS) analysis, to evaluate their biological and pharmacological properties: antioxidant (1, 1-diphenyl-2-pycrylhydrazyl (DPPH), 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic) (ABTS), galvinoxyle free radical scavenging, reducing power, phenanthroline and ß carotene-linoleic acid bleaching assays), enzymes inhibitory ability against several enzymes [acetyl-cholinesterase (AChE), buthyrylcholinesterase (BChE), urease and tyrosinase]. METHODS: Secondary metabolites were extracted from Tamarix africana air-dried powdered leaves by maceration, the crude extract was fractionated using different solvents with different polarities (Ethyl acetate, n-butanol and aqueous). The amount of polyphenols, flavonoids and tannins (hydrolysable and condensed) were determined using colorimetric assays. A variety of biochemical tests were carried out to assess antioxidant and oxygen radical scavenging properties using DPPH, ABTS, galvinoxyle free radical scavenging, reducing power, phenanthroline and ß carotene-linoleic acid bleaching methods. Neuroprotective effect was examined against acetylcholinesterase and buthy-rylcholinesterase enzymes. The anti-urease and anti-tyrosinase activities were performed against urease and tyrosinase enzymes respectively. The extract's components were identified using LC-MS and compared to reference substances. RESULTS: The results indicated that Tamarix africana extracts presented a powerful antioxidant activity in all assays and exhibited a potent inhibitory effect against AChE and BChE as well as urease and tyrosinase enzymes. LC-MS analysis identified amount of eight phenolic compounds were revealed in this analysis; Apigenin, Diosmin, Quercetin, Quercetine-3-glycoside, Apigenin 7-O glycoside, Rutin, Neohesperidin and Wogonin in methanolic extract and its different fractions of Tamarix africana from leaves. CONCLUSIONS: Based on these findings, it is reasonable to assume that Tamarix africana could be considered as a potential candidate for pharmaceutical, cosmetics, and food industries to create innovative health-promoting drugs.


Assuntos
Antioxidantes , Monofenol Mono-Oxigenase , Humanos , Antioxidantes/farmacologia , Antioxidantes/química , Monofenol Mono-Oxigenase/análise , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Acetilcolinesterase/análise , Acetilcolinesterase/metabolismo , Urease/análise , Urease/metabolismo , 1-Butanol/análise , Apigenina/análise , Ácido Linoleico/análise , Fenantrolinas/análise , beta Caroteno/análise , Folhas de Planta/química , Flavonoides/farmacologia , Radicais Livres , Glicosídeos/análise
11.
Magn Reson Chem ; 61(7): 443-447, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36960574

RESUMO

A new amide tricholomine C was isolated from the dried fruiting bodies of Tricholoma bakamatsutake. Its structure was identified by a combination of nuclear magnetic resonance spectroscopic analysis and electronic circular dichroism (ECD) calculations. The ethyl alcohol crude extract and tricholomines A-C from T. bakamatsutake were evaluated for neuroprotective activities. Of these substances, the crude extract showed weak neurite outgrowth-promoting activity in rat pheochromocytoma (PC12) cells, as well as weak inhibitory activities against acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE).


Assuntos
Acetilcolinesterase , Butirilcolinesterase , Ratos , Animais , Butirilcolinesterase/análise , Acetilcolinesterase/análise , Amidas/farmacologia , Amidas/análise , Carpóforos/química , Misturas Complexas/análise
12.
Anal Chem ; 95(9): 4479-4485, 2023 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-36802539

RESUMO

Most organophosphorus pesticide (OP) sensors reported in the literature rely on the inhibition effect of OPs on the activity of acetylcholinesterase (AChE), which suffer from the drawbacks of lack of selective recognition of OPs, high cost, and poor stability. Herein, we proposed a novel chemiluminescence (CL) strategy for the direct detection of glyphosate (an organophosphorus herbicide) with high sensitivity and specificity, which is based on the porous hydroxy zirconium oxide nanozyme (ZrOX-OH) obtained via a facile alkali solution treatment of UIO-66. ZrOX-OH displayed excellent phosphatase-like activity, which could catalyze the dephosphorylation of 3-(2'-spiroadamantyl)-4-methoxy-4-(3'-phosphoryloxyphenyl)-1,2-dioxetane (AMPPD) to generate strong CL. The experimental results showed that the phosphatase-like activity of ZrOX-OH is closely related to the content of hydroxyl groups on their surface. Interestingly, ZrOX-OH with phosphatase-like properties exhibited a unique response to glyphosate because of the consumption of the surface hydroxyl group by the unique carboxyl group of glyphosates and was thus employed to develop a CL sensor for direct and selective detection of glyphosate without using bio-enzymes. The recovery for glyphosate detection of cabbage juice ranged from 96.8 to 103.0%. We believe that the as-proposed CL sensor based on ZrOX-OH with phosphatase-like properties supplies a simpler and more highly selective approach for OP assay and provides a new method for the development of CL sensors for the direct analysis of OPs in real samples.


Assuntos
Acetilcolinesterase , Praguicidas , Acetilcolinesterase/análise , Praguicidas/análise , Compostos Organofosforados/análise , Luminescência , Monoéster Fosfórico Hidrolases
13.
Folia Histochem Cytobiol ; 61(1): 17-25, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36692115

RESUMO

INTRODUCTION: The available literature provides relatively little information on the morphology of the autonomic head ganglia in rodents including their neurochemical codding. MATERIAL AND METHODS: Morphological investigations of the otic ganglion of the chinchilla were performed using the modified acetylcholinesterase method. The cellular structure was investigated with histological techniques and neurochemical properties were studied with the double-labelling immunofluorescence method. RESULTS: Macromorphological investigations allowed the otic ganglion to be identified as a compact, oval agglomeration of neurons and nerve fibers. Multidimensional cross-sections revealed densely arranged neuronal perikarya and two populations of nerve cells differing in size were distinguished. The large cells (40-50 µm) accounted for about 80% of the neurons in the cross-sections. Moreover, a small number of intraganglionic nerve fibers was observed. Immunohistochemical staining revealed that over 85% of the neuronal cell bodies in the otic ganglion contained immunoreactivity to VAChT or ChAT. VIP-immunoreactive perikarya comprised approximately 10% of the ganglionic cells. Double staining revealed the presence of VAChT+ and NOS+ neurons which amounted to about 45% of the nerve cells in the otic ganglion. NOS+ only perikarya comprised approx. 15% of all the neurons. Immunoreactivity to enkephalins, substance P, somatostatin, and galanin was expressed in single nerve cell bodies and nerve fibers except numerous substance P+ intraganglionic nerve fibers. Some of them were stained also for CGRP. Single neurons stained for tyroxine hydroxylase. CONCLUSIONS: Our results, compared with findings in other rodent species suggest the existence of interspecies differences in the morphology, cellular structure, and immunohistochemical properties of the head autonomic ganglia in mammals.


Assuntos
Acetilcolinesterase , Substância P , Animais , Chinchila , Acetilcolinesterase/análise , Imunofluorescência , Neurônios/química
14.
J Neurol ; 270(4): 1945-1954, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36562850

RESUMO

OBJECTIVE: Alzheimer's disease (AD) is the most prevalent form of dementia among the aging population. Cumulative studies aim to find non-invasive biomarkers in the early stages of AD. Saliva can be obtained easily, and salivary biomarkers have been proven effective in detecting neurodegenerative diseases. To find effective biomarkers in saliva and to help the diagnosis of AD, we performed a meta-analysis focusing on the salivary biomarkers (ß-amyloid 1-42 (Aß1-42), total tau (t-tau), phosphorylated tau (p-tau) and acetylcholinesterase (AChE)) in AD. METHODS: We conducted a systematic online search for eligible studies reporting data on salivary biomarkers reflecting Aß1-42, t-tau, p-tau, and AChE in AD cohorts versus controls. Biomarkers' performance was assessed in a random-effects meta-analysis with the ratio of mean (RoM). RESULTS: A total of thirteen studies were included in the meta-analysis, of them seven involved salivary Aß1-42 (271 AD and 489 controls), five involved salivary t-tau (324 AD and 252 controls), four involved salivary p-tau (130 AD and 161 controls), and three involved salivary AChE (81 AD and 54 controls). AD showed significantly higher salivary Aß1-42 levels than control (ROM = 1.90 (95% CI 1.28-2.81, P = 0.001), while AD and control did not differ significantly on salivary t-tau, p-tau and AChE (ROM = 0.94, 95% CI 0.67-1.31, P = 0.72; ROM = 0.91, 95% CI 0.56-1.45, P = 0.68; ROM = 0.83, 95% CI 0.24-2.88, P = 0.77; respectively). CONCLUSION: The pooled results provide evidence that salivary Aß1-42 may serve as a sensitive biomarker for AD; nevertheless, larger AD cohorts are required to further confirm the sensitivity and specificity of salivary Aß1-42 for AD diagnosis.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Doença de Alzheimer/diagnóstico , Biomarcadores/análise , Peptídeos beta-Amiloides/análise , Saliva/química , Proteínas tau/análise , Acetilcolinesterase/análise , Humanos
15.
Anal Methods ; 14(43): 4292-4299, 2022 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-36285727

RESUMO

Organophosphorus nerve agents (OPNAs), such as Sarin (GB), Tabun (GA), Soman (GD) and VX, would cause tremendous harm in military and terrorist attacks, and thus the development of simple methods for the rapid and efficient detection of these hazardous substances is of great necessity. Herein, we present a novel approach for the facile, rapid and sensitive detection of real OPNAs. The detection substrate is fabricated using functionalized silver nanoparticles (AgNPs) immobilized with acetylcholinesterase (AChE) and 5,5'-dithiobis-(2-nitrobenzoic acid) (DTNB). In the absence of OPs, AChE catalyzes the hydrolysis of acetylthiocholine (ATCh) to form thiocholine (TCh), which continues to interact quickly with DTNB to produce a very sensitive Raman probing molecule, TNB. The inhibition of the activity of AChE by OPs could induce an obvious decrease of characteristic Raman peaks of 5-thio-2-nitrobenzoic acid (TNB) at 1335 cm-1. The introduction of DTNB as an enzyme activity indicator significantly improves the detection sensitivity with distinct characteristic Raman peaks. The LOD of GD, which is one of the most easily aged OPNAs, could reach 0.1 nM due to its strongest inhibition of AChE. Moreover, various OPNAs exhibit different SERS intensities due to their different inhibition capacities of AChE. Hence, the new strategy has great potential in public security early warning and environmental analysis.


Assuntos
Nanopartículas Metálicas , Agentes Neurotóxicos , Acetilcolinesterase/análise , Acetilcolinesterase/química , Ácido Ditionitrobenzoico , Compostos Organofosforados/análise , Compostos Organofosforados/química , Nanopartículas Metálicas/química , Prata , Análise Espectral Raman
16.
Plant Foods Hum Nutr ; 77(4): 545-551, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36040657

RESUMO

The current study reports for the first time the nutritional, fruit volatiles, phytochemical, and biological characteristics of Ferocactus herrerae J. G. Ortega fruits. The nutritional analysis revealed that carbohydrate (20.6%) was the most abundant nutrient followed by dietary fibers (11.8%), lipids (0.9%), and proteins (0.8%). It was rich in vitamins, minerals, essential, and non-essential amino acids. Gas chromatography-mass spectrometry (GC-MS) analysis of the headspace-extracted volatiles showed that 3-methyl octadecane (35.72 ± 2.38%) was the major constituent detected. Spectrophotometric determination of total phenolic and flavonoid contents of the fruit methanolic extract (ME) showed high total phenolic [9.17 ± 0.87 mg/g gallic acid equivalent (GAE)] and flavonoid [4.99 ± 0.23 mg/g quercetin equivalent (QE)] contents. The ME was analyzed using high-performance liquid chromatography with ultraviolet (HPLC-UV), which allowed for both qualitative and quantitative estimation of 16 phenolic compounds. Caffeic acid was the major phenolic acid identified [45.03 ± 0.45 mg/100 g dried powdered fruits (DW)] while quercitrin (52.65 ± 0.31 mg/100 g DW), was the major flavonoid detected. In-vitro assessment of the antioxidant capacities of the ME revealed pronounced activity using three comparative methods; 2, 2-diphenyl-1-picrylhydrazyl (DPPH) (132.06 ± 2.1 µM Trolox equivalent (TE) /g), 2,2'-azino-di(3-ethylbenzthiazoline-6-sulfonic acid (ABTS), (241.1 ± 5.03 uM TE/g), and ferric reducing antioxidant power (FRAP) (258.9 ± 1.75 uM TE/g). Besides, remarkable anti-inflammatory [COX-1 (IC50 = 20.2 ± 1.1 µg/mL) and COX-2 (IC50 = 9.8 ± 0.64 µg/mL)] and acetylcholinesterase inhibitory (IC50 = 1.01 ± 0.39 mg/mL) activities were observed. Finally, our results revealed that these fruits could be used effectively as functional foods and nutraceuticals suggesting an increase in their propagation.


Assuntos
Antioxidantes , Frutas , Frutas/química , Antioxidantes/análise , Acetilcolinesterase/análise , Quercetina/análise , Ciclo-Oxigenase 2/análise , Extratos Vegetais/química , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/análise , Fenóis/análise , Flavonoides/farmacologia , Flavonoides/análise , Ácido Gálico/análise , Ácidos Cafeicos/análise , Ácidos Sulfônicos/análise , Vitaminas/análise , Fibras na Dieta/análise , Carboidratos/análise , Aminoácidos/análise , Lipídeos/análise
17.
Virchows Arch ; 481(2): 245-252, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35513609

RESUMO

Rectal suction biopsy (RSB) is a gold standard for diagnosing Hirschsprung disease (HD). Calretinin staining of RSB is increasingly used by experienced pathologists due to non-complex examination and comparable diagnostic accuracy with acetylcholinesterase (AChE). However, the diagnostic accuracy of calretinin examined by unexperienced pathologists remains to be elucidated. Therefore, we aim to compare diagnostic accuracy of calretinin with AChE on RSB for diagnosing HD when examined by unexperienced pathologists. We prospectively analyzed sections from RSB stained with AChE + HE and calretinin. Blinded examination was done by five unexperienced pathologists (pathology residents) and three experienced pathologists (senior pediatric gastro-enterology pathologists) assessing for the presence of HD. Cases for the study included ones proven to be HD on resection specimens and cases without HD. Diagnostic accuracy was determined calculating area under the curve (AUC), sensitivity, specificity, likelihood ratio, and posttest probability. Fleiss' kappa analysis was performed to assess interobserver agreement between reviewers. Eleven of 18 included patients (61%) were diagnosed with HD. Comparing the diagnostic accuracy of unexperienced pathologists, calretinin versus AChE + HE showed sensitivity of 80.0% versus 74.5% and specificity of 100% versus 65.4%, AUC of 0.87 (0.78-0.96) versus 0.59 (0.45-0.72). Unexperienced pathologists showed substantial agreement with calretinin (kappa 0.72 [0.61-0.84]) and fair agreement with AChE + HE (kappa 0.34 [0.23-0.44]). We found calretinin having higher diagnostic accuracy in diagnosing HD compared to AChE + HE when examined by unexperienced pathologists. Therefore, we recommend to use calretinin as the standard technique for staining RSB in diagnosing HD.


Assuntos
Doença de Hirschsprung , Acetilcolinesterase/análise , Acetilcolinesterase/metabolismo , Biópsia/métodos , Calbindina 2/análise , Criança , Doença de Hirschsprung/diagnóstico , Humanos , Lactente , Patologistas , Reto/patologia , Coloração e Rotulagem , Sucção
18.
Anal Methods ; 14(15): 1479-1489, 2022 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-35343530

RESUMO

Analytical method development for the control of pesticide residues occurring in significant dietary foodstuffs is of utmost importance considering their potential impact on consumer health and food market sustainability. Depending on the purpose, either instrumental analysis, mainly chromatographic methods, or screening assays, mostly using biorecognition affinity, are commonly used, featuring different advantages and drawbacks. To practically compare these two different types of analytical strategies, we applied them for the detection of (i) 97 organophosphate (OP) and carbamate (CM) pesticide residues in wheat flour and (ii) carbofuran (a carbamate insecticide) in wheat, rye and maize flour samples. Regarding high-end analysis, an ultra-high-performance liquid chromatography coupled with triple quadrupole mass spectrometry (UHPLC-QqQ-MS) method was developed and validated achieving low limits of quantification (LOQs, from 0.002 to 0.040 mg kg-1) and a short chromatographic run (12 min). In terms of bioanalytical methods, a fast (17 min) and cost-efficient (∼0.01€ per sample) acetylcholinesterase (AChE) microplate assay for carbofuran screening was utilized. Importantly, carbofuran was the strongest of the 11 OP and CM tested pesticides achieving a half maximal inhibitory concentration (IC50) of 0.021 µM whilst the assay detectability was at the parts per billion level in all three cereal matrices. Based on the attained results, a critical discussion is presented providing the analytical merits and bottlenecks for each case and a wider outlook related to the application of analytical methods in the food safety control analytical scheme.


Assuntos
Carbofurano , Resíduos de Praguicidas , Praguicidas , Acetilcolinesterase/análise , Carbofurano/análise , Inibidores da Colinesterase/análise , Cromatografia Líquida de Alta Pressão/métodos , Grão Comestível/química , Ensaios Enzimáticos , Farinha/análise , Espectrometria de Massas/métodos , Resíduos de Praguicidas/análise , Praguicidas/análise , Triticum
19.
Georgian Med News ; (323): 101-105, 2022 Feb.
Artigo em Russo | MEDLINE | ID: mdl-35271479

RESUMO

Aim - based on the clincal experience of monitoring and treatment of teenagers with Hirschsprung's disease (HD), to study clinical aspects of the disease in older children and to establish an adequate diagnostic and treatment policy. The paper is based on the analysis of the results of examination and treatment of 26 children with Hirschsprung's disease, who were first diagnosed with the disease at the age of 10 years and older. There were 19 (73.08%) boys and 7 (26.92%) girls. The following diagnostic methods were used: X-ray examination of the large intestine, ultrasonography of the abdominal organs and the large intestine, rectosigmoidoscopy, morphological examination of biopsy material, immunohistological examination for acetylcholinesterase (AChE). Nonparametric statistical methods were used due to the small sample and the prevalence of the analysis of qualitative rather than quantitative criteria. Hirschsprung's disease in older children has a latent course with long periods of functional compensation. The rectal form of pathology predominates (57.69%). The main diagnostic methods are anamnesis, features of the clinical course of the pathology, irrigoscopy, morphological examination of full-thickness rectal biopsies and immunohistochemical examination of the rectal mucosa for AChE. 84,62% of teenagers underwent one-stage surgery without postoperative complications; 15,38% of patients had indications for colostomy.


Assuntos
Doença de Hirschsprung , Acetilcolinesterase/análise , Adolescente , Biópsia , Criança , Feminino , Doença de Hirschsprung/diagnóstico por imagem , Doença de Hirschsprung/cirurgia , Humanos , Masculino , Complicações Pós-Operatórias , Reto/diagnóstico por imagem , Reto/cirurgia
20.
PeerJ ; 10: e12722, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35036098

RESUMO

Bee pollen (BP) is full of nutrients and phytochemicals, and so it is widely used as a health food and alternative medicine. Its composition and bioactivity mainly depend on the floral pollens. In this work, BP collected by Apis mellifera with different monoculture flowering crops (BP1-6) were used. The types of floral pollen in each BP were initially identified by morphology, and subsequently confirmed using molecular phylogenetic analysis. Data from both approaches were consistent and revealed each BP to be monofloral and derived from the flowers of Camellia sinensis L., Helianthus annuus L., Mimosa diplotricha, Nelumbo nucifera, Xyris complanata, and Ageratum conyzoides for BP1 to BP6, respectively. The crude extracts of all six BPs were prepared by sequential partition with methanol, dichloromethane (DCM), and hexane. The crude extracts were then tested for the in vitro (i) α-amylase inhibitory, (ii) acetylcholinesterase inhibitory (AChEI), and (iii) porcine pancreatic lipase inhibitory (PPLI) activities in terms of the percentage enzyme inhibition and half maximum inhibitory concentration (IC50). The DCM partitioned extract of X. complanata BP (DCMXBP) had the highest active α-amylase inhibitory activity with an IC50 value of 1,792.48 ± 50.56 µg/mL. The DCM partitioned extracts of C. sinensis L. BP (DCMCBP) and M. diplotricha BP (DCMMBP) had the highest PPLI activities with an IC50 value of 458.5 ± 13.4 and 500.8 ± 24.8 µg/mL, respectively), while no crude extract showed any marked AChEI activity. Here, the in vitro PPLI activity was focused on. Unlike C. sinensis L. BP, there has been no previous report of M. diplotricha BP having PPLI activity. Hence, DCMMBP was further fractionated by silica gel 60 column chromatography, pooling fractions with the same thin layer chromatography profile. The pooled fraction of DCMMBP2-1 was found to be the most active (IC50 of 52.6 ± 3.5 µg/mL), while nuclear magnetic resonance analysis revealed the presence of unsaturated free fatty acids. Gas chromatography with flame-ionization detection analysis revealed the major fatty acids included one saturated acid (palmitic acid) and two polyunsaturated acids (linoleic and linolenic acids). In contrast, the pooled fraction of DCMMBP2-2 was inactive but pure, and was identified as naringenin, which has previously been reported to be present in M. pigra L. Thus, it can be concluded that naringenin was compound marker for Mimosa BP. The fatty acids in BP are nutritional and pose potent PPLI activity.


Assuntos
Acetilcolinesterase , Ácidos Graxos , Abelhas , Animais , Suínos , Ácidos Graxos/análise , Acetilcolinesterase/análise , Filogenia , Pólen/química , Lipase/análise , alfa-Amilases/análise
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...