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1.
Cell Rep Med ; : 101513, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38608697

RESUMO

Bacteria-based therapies are powerful strategies for cancer therapy, yet their clinical application is limited by a lack of tunable genetic switches to safely regulate the local expression and release of therapeutic cargoes. Rapid advances in remote-control technologies have enabled precise control of biological processes in time and space. We developed therapeutically active engineered bacteria mediated by a sono-activatable integrated gene circuit based on the thermosensitive transcriptional repressor TlpA39. Through promoter engineering and ribosome binding site screening, we achieved ultrasound (US)-induced protein expression and secretion in engineered bacteria with minimal noise and high induction efficiency. Specifically, delivered either intratumorally or intravenously, engineered bacteria colonizing tumors suppressed tumor growth through US-irradiation-induced release of the apoptotic protein azurin and an immune checkpoint inhibitor, a nanobody targeting programmed death-ligand 1, in different tumor mouse models. Beyond developing safe and high-performance designer bacteria for tumor therapy, our study illustrates a sonogenetics-controlled therapeutic platform that can be harnessed for bacteria-based precision medicine.

2.
Nat Commun ; 15(1): 1122, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38321056

RESUMO

Gene therapies provide treatment options for many diseases, but the safe and long-term control of therapeutic transgene expression remains a primary issue for clinical applications. Here, we develop a muscone-induced transgene system packaged into adeno-associated virus (AAV) vectors (AAVMUSE) based on a G protein-coupled murine olfactory receptor (MOR215-1) and a synthetic cAMP-responsive promoter (PCRE). Upon exposure to the trigger, muscone binds to MOR215-1 and activates the cAMP signaling pathway to initiate transgene expression. AAVMUSE enables remote, muscone dose- and exposure-time-dependent control of luciferase expression in the livers or lungs of mice for at least 20 weeks. Moreover, we apply this AAVMUSE to treat two chronic inflammatory diseases: nonalcoholic fatty liver disease (NAFLD) and allergic asthma, showing that inhalation of muscone-after only one injection of AAVMUSE-can achieve long-term controllable expression of therapeutic proteins (ΔhFGF21 or ΔmIL-4). Our odorant-molecule-controlled system can advance gene-based precision therapies for human diseases.


Assuntos
Alprostadil , Cicloparafinas , Camundongos , Humanos , Animais , Alprostadil/metabolismo , Transgenes , Cicloparafinas/metabolismo , Odorantes , Receptores Acoplados a Proteínas G/metabolismo , Dependovirus/genética , Vetores Genéticos
3.
Nat Chem Biol ; 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37872400

RESUMO

Cell-based therapies represent potent enabling technologies in biomedical science. However, current genetic control systems for engineered-cell therapies are predominantly based on the transcription or translation of therapeutic outputs. Here we report a protease-based rapid protein secretion system (PASS) that regulates the secretion of pretranslated proteins retained in the endoplasmic reticulum (ER) owing to an ER-retrieval signal. Upon cleavage by inducible proteases, these proteins are secreted. Three PASS variants (chemPASS, antigenPASS and optoPASS) are developed. With chemPASS, we demonstrate the reversal of hyperglycemia in diabetic mice within minutes via drug-induced insulin secretion. AntigenPASS-equipped cells recognize the tumor antigen and secrete granzyme B and perforin, inducing targeted cell apoptosis. Finally, results from mouse models of diabetes, hypertension and inflammatory pain demonstrate light-induced, optoPASS-mediated therapeutic peptide secretion within minutes, conferring anticipated therapeutic benefits. PASS is a flexible platform for rapid delivery of therapeutic proteins that can facilitate the development and adoption of cell-based precision therapies.

4.
Materials (Basel) ; 16(19)2023 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-37834485

RESUMO

Microbially induced carbonate precipitation (MICP) technology holds great potential in enhancing soil properties. MICP can be employed to enhance the stability and strength of diverse sandy soil, but it has the shortcoming of low curing efficiency. In response to the identified problem, this study aims to investigate an optimized treatment protocol that involves formulating a cementing solution in a hydrochloric acid (HCl) solution to enhance the solidification rate in the MICP reaction and evaluate its effectiveness. The results indicate that when preparing a 1 M cementing solution in a 0.2 M HCl solution, it promotes the rapid bonding of calcareous sand particles, resulting in an unconfined compressive strength (UCS) of 1312.6 kPa in the sand column after five treatments. Compared to the conventional test group, the experimental group containing HCl exhibited an approximately 1357% increase in UCS. The analysis unveiled the pivotal role of metal ions dissolved from calcareous sand by HCl in enhancing the UCS of MICP-treated calcareous sand. The proposed experimental methodology serves as a valuable tool for designing treatment strategies for MICP-cemented calcareous sand in practical engineering applications.

6.
J Biosci Bioeng ; 136(5): 383-390, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37775439

RESUMO

The high purine diet could result in the increase of the level of blood uric acid, causing serious health problems such as hyperuricemia, gout, nephropathy and cardiovascular diseases. To find out a safe, cheap and super adsorption material for removing purines in stomach or pretreating high-purine beverages, we used different tissues of pomelo peel to prepare biomass carbon by drying, chemical modification and carbonization and then applied it to remove purine compounds in strong acidic solution, beer and soybean milk. The characteristic analysis of pomelo-peel-derived carbons (PPCs) indicated that the preparation methods significantly affected the structures and adsorption capacities of PPCs. Compared with the biomass carbon derived from bamboo, PPCs exhibited higher adsorption capabilities for purine compounds in strong acidic solution (adsorption rates > 99% in 15 min) and soybean milk (adsorption rates > 56% in 30 min) but slightly lower adsorption capabilities in beer (adsorption rates > 52% in 30 min). In addition, the adsorption capabilities of PPCs for purine compounds in beer and soybean milk were not obviously affected by temperatures. Therefore, PPCs are promising absorbents for applications in removing purine compounds from beverages to produce low-purine, healthier products for treating hyperuricemia. The strong adsorption capabilities of PPCs on purine compounds in strong acidic environment also provides a possibility of using the PPCs as food additives for removing purines in stomach for healthcare applications such as gout prevention after confirming their biosafety.

7.
CNS Neurosci Ther ; 29(8): 2281-2291, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36942519

RESUMO

INTRODUCTION: The etiology of Parkinson's disease (PD) is still unknown. Until now, oxidative stress and neuroinflammation play a crucial role in the pathogenesis of PD. However, the specific synergistic role of oxidative stress and neuroinflammation in the occurrence and development of PD remains unclear. METHODS: The changes in motor behavior, dopamine (DA) neurons quantification and their mitochondrial respiratory chain, glial cells activation and secreted cytokines, Nrf2 signaling pathway, and redox balance in the brain of rats were evaluated. RESULTS: Lipopolysaccharide (LPS)-induced neuroinflammation and rotenone (ROT)-induced oxidative stress synergistically aggravated motor dysfunction, DA neuron damage, activation of glial cells, and release of related mediators, activation of Nrf2 signaling and destruction of oxidative balance. In addition, further studies indicated that after ROT-induced oxidative stress caused direct damage to DA neurons, LPS-induced inflammatory effects had stronger promoting neurotoxic effects on the above aspects. CONCLUSIONS: Neuroinflammation and oxidative stress synergistically aggravated DA neuronal loss. Furtherly, oxidative stress followed by neuroinflammation caused more DA neuronal loss than neuroinflammation followed by oxidative stress.


Assuntos
Doença de Parkinson , Rotenona , Ratos , Animais , Rotenona/toxicidade , Rotenona/metabolismo , Lipopolissacarídeos/toxicidade , Dopamina/metabolismo , Doenças Neuroinflamatórias , Fator 2 Relacionado a NF-E2/metabolismo , Doença de Parkinson/metabolismo , Estresse Oxidativo , Neurônios Dopaminérgicos/metabolismo
8.
Bioeng Transl Med ; 8(2): e10455, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36925673

RESUMO

The intestinal flora has become very active in studies related to Parkinson's disease (PD) in recent years. The microbe-gut-brain axis is closely related to the maintenance of brain homeostasis as well as PD pathogenesis. Alterations in gut bacteria can contribute to neuroinflammation and dopamine (DA) neurodegeneration. Lactobacillus murinus, a gram-positive bacterium, is a commensal gut bacteria present in the mammalian gut and considered as a potential probiotic due to its beneficial effects, including anti-inflammatory and antibacterial actions. In this study, the effects of live L. murinus and heat-killed L. murinus on DA neuronal damage in rats and the underlying mechanisms were investigated. Data showed that heat-killed L. murinus ameliorated 6-hydroxydopamine-induced motor dysfunctions and loss of substantia nigra DA neurons, while no protection was shown in live L. murinus treatment. At the same time, heat-killed L. murinus reduced the activation of NLRP3 inflammasome in microglia and the secretion of pro-inflammatory factors, thus inhibiting the development of neuroinflammation. Furthermore, heat-killed L. murinus failed to display its original neuroprotective properties in NLRP3 inflammasome knockout mice. Together, heat-killed L. murinus conferred neuroprotection against DA neuronal loss via the inhibition of microglial NLRP3 inflammasome activation. These findings provide a promising potential for future applications of L. murinus, and also beneficial strategy for PD treatment.

9.
MethodsX ; 10: 102083, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36875344

RESUMO

The detection of neurotransmitters has extensively been applied to the study of the pathogenesis, diagnosis, and therapeutic effect of drugs on many neuropsychiatric diseases. High-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) has been employed to determine neurotransmitters levels due to its distinct advantages. However, neurotransmitter detection still presents some challenges. A rapid and sensitive HPLC-MS/MS protocol has been established in our lab, which can simultaneously detect 5 neurotransmitters with an easy pretreatment procedure. The protocol provides demanded reference value for the lab using an Agilent HPLC-MS/MS system with a triple quadrupole analyzer.

10.
World J Clin Cases ; 11(8): 1808-1813, 2023 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-36969997

RESUMO

BACKGROUND: A giant juvenile fibroadenoma (GJF) is a rare, benign breast tumor that affects females < 18 years of age. GJFs are generally suspected based on a palpable mass. GJFs influence breast shape and mammary gland development via the pressure effect from their enormous size. CASE SUMMARY: Herein we report a case involving a 14-year-old Chinese female with a GJF in the left breast. GJF is a rare, benign breast tumor that usually occurs between 9 and 18 years of age and accounts for 0.5%-4.0% of all fibroadenomas. In severe cases, breast deformation may occur. This disease is rarely reported in Chinese people and has a high clinical misdiagnosis rate due to the absence of specific imaging features. On July 25, 2022, a patient with a GJF was admitted to the First Affiliated Hospital of Dali University. The preoperative clinical examination and conventional ultrasound diagnosis needed further clarification. The mass was shown to be an atypical lobulated mass during the operation and confirmed to be a GJF based on pathologic examination. CONCLUSION: GJF is also a rare, benign breast tumor in Chinese women. Evaluation of such masses consists of a physical examination, radiography, ultrasonography, computer tomography, and magnetic resonance imaging. GJFs are confirmed by histopathologic examination. Mastectomy is not selected when the patient benefits from a complete resection of the mass with breast reconstruction and an uneventful recovery.

11.
Materials (Basel) ; 15(21)2022 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-36363020

RESUMO

In order to improve the tribological properties of Ti-6Al-4V alloy and further broaden the application scope of titanium alloy materials in the industrial field, a preparation method of a waterjet-guided high-power laser processing surface microgroove was studied. In this paper, a multifocus coupling lens was innovatively designed to replace the spherical lens in the traditional waterjet-guided laser coupling device, which avoids the gas explosion phenomenon in the coupling of the high-power laser and waterjet, and realizes the high-quality coupling of the high-power laser and water beam fiber. Then, with the microgroove morphology as the response target, the single-factor test and response surface test of the water-guided laser processing microgroove were carried out. Based on the experimental results, an approximate mathematical model of the response surface between the process parameters and the microgroove topography target was constructed, and the quantitative relationship between the waterjet-guided laser processing parameters and the target response was studied. At the same time, the optimal combination of process parameters was obtained by multiobjective optimization, so as to effectively improve the microgroove morphology. This technology provides method guidance and a decision-making reference for subsequent waterjet-guided laser processing of titanium alloy surface functional microstructures.

12.
Micromachines (Basel) ; 13(9)2022 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-36143997

RESUMO

Due to the special manufacturing process of cobalt-chromium alloy cardiovascular stent tubes, there are serious surface defects in their inner walls, which affects the therapeutic effect after implantation. At the same time, the traditional processing technology cannot finish the inner wall of a cardiovascular stent tube. In light of the above problems, magnetic abrasive finishing (MAF) equipment for the inner wall of an ultra-fine and ultra-long cardiovascular stent tube is proposed, and MAF technology is used to improve the surface quality of its inner wall. High-performance spherical magnetic abrasive powders are used to finish the inner wall of a cobalt-chromium alloy cardiovascular stent tube with an inner diameter of 1.6 mm and an outer diameter of 1.8 mm. The effects of finishing time, tube rotational speed, feed speed of the magnetic pole, MAPs filling quantity, and MAP abrasive size on the surface roughness and material removal thickness of cobalt-chromium alloy cardiovascular stent tube are investigated. The results show that the surface roughness of the inner wall of the cobalt-chromium alloy cardiovascular stent decreases from 0.485 µm to 0.101 µm, and the material removal thickness of the defect layer is 4.3 µm. MAF technology is used to solve the problem of the poor surface quality of the inner walls of ultra-fine and ultra-long cobalt-chromium alloy cardiovascular stent tubes.

13.
Micromachines (Basel) ; 13(9)2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36144071

RESUMO

In this paper, the surface roughness of SiC ceramics was investigated in laser-assisted machining (LAM) processes; machine learning was used to predict surface roughness and to optimize the process parameters, and therefore, to ultimately improve the surface quality of a workpiece and obtain excellent serviceability. First, single-factor turning experiments were carried out on SiC ceramics using LAM according to the material removal mechanism to investigate the variation trend of the effects of different laser powers, rotational speeds, feed rates, and cutting depths on surface roughness. Then, laser power, rotational speed, feed rate and cutting depth were selected as the four factors, and the surface roughness was used as the target value for the orthogonal experiments. The results of the single-factor experiments and the orthogonal experiments were combined to construct a prediction model based on the combination of the grey wolf optimization (GWO) algorithm and support vector regression (SVR). The coefficient of determination (R2) of the optimized prediction model reached 0.98676 with an average relative error of less than 2.624%. Finally, the GWO algorithm was used to optimize the global parameters of the prediction model again, and the optimal combination of process parameters was determined and verified by experiments. The actual minimum surface roughness (Ra) value was 0.418 µm, and the relative error was less than 1.91% as compared with the predicted value of the model. Therefore, the prediction model based on GWO-SVR can achieve accurate prediction of the surface roughness of SiC ceramics in LAM and can obtain the optimum surface roughness using parameter optimization.

14.
Materials (Basel) ; 15(14)2022 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-35888357

RESUMO

In this study, laser-assisted machining experiments are carried out on silicon carbide (SiC) ceramic materials by a turning process, and laser power, cutting depth, rotational speed, and feed speed are selected as research factors. In order to improve the surface processing quality of laser-assisted turning of SiC ceramics and obtain the smallest surface roughness, the orthogonal method and response surface method are used to investigate the effect of various factors on surface roughness. The effect of various factors on surface roughness is evaluated by variance analysis, mean analysis, main effect diagram, 3D response surface, and corresponding contour diagram. The surface roughness prediction model is established based on the response surface method, and the prediction error is 4.1% with high accuracy. The experimental results show that laser power and cutting depth are the most significant factors affecting surface roughness, and rotational speed is a significant factor affecting surface roughness. Under the optimum process conditions, the smallest surface roughness Ra obtained by the response surface method is 0.294 µm, which is lower than 0.315 µm obtained by the orthogonal method, and the surface quality is higher. Therefore, the optimal process parameters of the response surface method can obtain the smallest surface roughness and higher surface quality in laser-assisted turning of SiC ceramics.

15.
Zhongguo Zhong Yao Za Zhi ; 47(14): 3968-3976, 2022 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-35850857

RESUMO

In recent years, with the acceleration of population aging in China, the frequent occurrence of chronic diseases, and the increase in the number of sub-health groups, people began to seek ways to maintain health in line with the laws of nature. Healthy China has become a national strategy, and the Big Health industry has ushered in a golden period of development. In this context, the concept of medicine and food homology and edible medicinal substances which have guided Chinese people to pursue health since ancient times have ushered in significant and favorable development opportunities, and the industrial scale has gradually expanded. The development and utilization of edible medicinal plants have also become an important research direction. In the industrialization process of modern health care and edible medicinal products, a large number of drug residues are often abandoned due to ineffective utilization, resulting in a huge waste of resources and increasing the pressure on the ecological environment. Under the guidance of the homology theory of medicine and food, based on the recycling strategy of Chinese medicine resources, this paper analyzed the inherent common characteristics such as physical and chemical properties and biological activity of Chinese medicine residues of edible medicinal plants and put forward some suitable resource utilization strategies and suggestions in combination with the current situation of resource development and utilization of Chinese medicine residues of edible medicinal plants, in order to promote the high-value development and utilization of medicinal and edible resources, and extend the industrial chain of edible medicinal resources, thereby empowering Big Health industry and facilitating Healthy China.


Assuntos
Plantas Comestíveis , Plantas Medicinais , China , Conservação dos Recursos Naturais , Humanos , Indústrias , Medicina Tradicional Chinesa
16.
Front Pharmacol ; 13: 846541, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35586062

RESUMO

Alzheimer's disease (AD) is a neurodegenerative disorder recognized as a global public health priority. Although available treatments temporarily relieve the symptoms, they could not prevent the progression of cognitive decline. Natural compounds have been rich sources for drug discovery. Dendrobium nobile Lindl. alkaloid (DNLA) is the main active compound in Dendrobium nobile Lindl, a traditional Chinese herbal medicine. Recent studies indicated that DNLA produced neuroprotection. However, the mechanisms underlying DNLA-generated neuroprotection remain unknown. To investigate neuroprotection and the underlying mechanisms of DNLA, mouse hippocampus injection of lipopolysaccharide (LPS)-induced neuronal damage was performed. DNLA protected hippocampus neurons and working memory disorder against LPS-induced neurotoxicity. In addition, DNLA suppressed cell undergoing membrane lysis and cell swelling and inhibited the essential mediator of pyroptosis GSDMD-N expressions. Furthermore, DNLA-mediated neuroprotection was dependent on the inhibition of NLRP3 inflammasome activation, as evidenced by the fact that DNLA reduced pro-inflammatory factor (IL-18 and IL-1ß) production and inhibited the expression of related proteins. DNLA-exerted neuroprotection against LPS-induced neuronal damage, and cognitive impairment was not observed in NLRP3 knockout mice. Together, this study suggested that DNLA attenuated NLRP3-mediated pyroptosis to generate neuroprotection against LPS-induced neuronal damage and cognitive impairment.

17.
Polymers (Basel) ; 14(5)2022 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-35267751

RESUMO

In road construction, a large number of excavated soils need to be treated with stabilizers. The addition of superabsorbent polymer (SAP) can improve the road performance of these stabilized soils. In order to predict roadbed deformation, dynamic triaxial tests were carried out on cemented soil containing SAP to investigate its resilient and plastic strain behavior. The effects of SAP content, cyclic stress ratio, and loading frequency on cement-stabilized soils with SAP were analyzed combined with the number of cycles. This study demonstrates how these influencing factors effect the resilient strain, dynamic elastic modulus, and accumulated plastic strain, which are crucial to better understanding the strain behavior of cement-stabilized soil with SAP. The results show that SAP can significantly improve the brittle failure characteristics and dynamic strength of cement-stabilized soil. Soil with higher SAP content possesses smaller accumulated plastic strain; with the increase in the cyclic stress ratio, the dynamic elastic modulus decreases significantly, whereas the accumulated plastic strain has the opposite trend. In addition, the lower frequency produces larger cumulative axial strain.

18.
Zhongguo Zhong Yao Za Zhi ; 47(2): 412-418, 2022 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-35178983

RESUMO

Farnesyl diphosphate synthase(FPPS) is a key enzyme at the branch point of the sesquiterpene biosynthetic pathway, but there are no reports on the transcriptional regulation of FPPS promoter in Pogostemon cabin. In the early stage of this study, we obtained the binding protein PcFBA-1 of FPPS gene promoter in P. cabin. In order to explore the possible mechanism of PcFBA-1 involved in the regulation of patchouli alcohol biosynthesis, this study performed PCR-based cloning and sequencing analysis of PcFBA-1, analyzed the expression patterns of PcFBA-1 in different tissues by fluorescence quantitative PCR and its subcellular localization using the protoplast transformation system, detected the binding of PcFBA-1 protein to the FPPS promoter in vitro with the yeast one-hybrid system, and verified its transcriptional regulatory function by dual-luciferase reporter gene assay. The findings demonstrated that the cloned PcFBA-1 had an open reading frame(ORF) of 1 131 bp, encoding a protein of 376 amino acids, containing two conserved domains named F-box-like superfamily and FBA-1 superfamily, and belonging to the F-box family. Moreover, neither signal peptide nor transmembrane domain was contained, implying that it was an unstable hydrophilic protein. In addition, as revealed by fluorescence quantitative PCR results, PcFBA-1 had the highest expression in leaves, and there was no significant difference in expression in roots or stems. PcFBA-1 protein was proved mainly located in the cytoplasm. Furthermore, yeast one-hybrid screening and dual-luciferase reporter gene assay showed that PcFBA-1 was able to bind to FPPS promoter both in vitro and in vivo to enhance the activity of FPPS promoter. In summary, this study identifies a new transcription factor PcFBA-1 in P. cabin, which directly binds to the FPPS gene promoter to enhance the promoter activity. This had laid a foundation for the biosynthesis of patchouli alcohol and other active ingre-dients and provided a basis for metabolic engineering and genetic improvement of P. cabin.


Assuntos
Pogostemon , Sequência de Aminoácidos , Clonagem Molecular , Geraniltranstransferase/genética , Fatores de Transcrição/genética
19.
Support Care Cancer ; 30(4): 3241-3247, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34984550

RESUMO

PURPOSE: To explore the effectiveness of micturition interruption exercise in improving the incidence of urinary incontinence after radical prostatectomy. MATERIALS AND METHODS: With a retrospective case-control study, 96 patients admitted in the Second Affiliated Hospital of Zhejiang Chinese Medical University from August 2014 to August 2020 and underwent radical prostatectomy were collected as the subjects. Those patients who used micturition interruption exercise (n = 48) were set as the therapy group, and the control group was collected according to the ratio of 1:1; the patients used Kegel exercise (n = 48) to compare the rehabilitation of urinary incontinence in patients and the effect of training compliance on rehabilitation. RESULTS: The recovery time of urinary incontinence in the therapy group was significantly shorter than that of the control group. In the therapy group, 83.3% of patients with training compliance reached an average or above, while the control group only accounted for 58.3%. International Consultation on Incontinence Questionnaire Short-Form score of the therapy group was lower than that of the control group after surgery. Spearman analysis suggests that there is a negative correlation between the postoperative urinary incontinence recovery time and compliance with the micturition interruption exercise. CONCLUSIONS: Micturition interruption exercise could not only improve the compliance of patients with exercise, but also significantly shorten the recovery time of urinary incontinence after radical prostatectomy.


Assuntos
Incontinência Urinária , Micção , Estudos de Casos e Controles , Terapia por Exercício , Humanos , Masculino , Prostatectomia/efeitos adversos , Prostatectomia/reabilitação , Estudos Retrospectivos , Incontinência Urinária/epidemiologia , Incontinência Urinária/etiologia , Incontinência Urinária/prevenção & controle
20.
Se Pu ; 40(1): 28-40, 2022 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-34985213

RESUMO

Given the wide variety of fentanyl analogs, the test for this entire group tends to be crucial and particularly difficult since all fentanyl-like substances are listed as controlled substances in China. This study meticulously analyzed the fragmentation pathways and mechanisms of 29 fentanyl analogs and summarized the fragmentation pathways and features for the entire group of fentanyl analogs, thus providing a reference for related screening tests. Fentanyl, thiofentanyl, and sufentanil were selected as the representative compounds in this study, and the fragmentation mechanism of their fragment ions was interpreted. The general fragmentation rules for fentanyl analogs were summarized as well. The fragment ions of the three compounds formed by induced cleavage (i) came with high abundance ratios, such as fragment ions of m/z 188, 105, 194, 111, and 238, while the induced cleavage was due to the amide and piperidinyl groups. Moreover, the induction ability of amide group was significantly stronger than that of the piperidinyl group, and induced cleavage was the main fragmentation pathway for most of the fentanyl analogs. Furthermore, the fragment ions with m/z 281 and 287 for fentanyl and thiofentanyl were formed by loss of the propionyl group after single H rearrangement (rH). The fragment ions with m/z 216, 146, and 132 for fentanyl and thiofentanyl were formed by double H rearrangement (r2H). Although their abundance ratios were not high, they still had specificity and regularity. Elimination reaction (re) was also a very common fragmentation pathway for these compounds, leading to fragment ions with m/z 134 and 140. Phenylethyl substituents were more prone to the elimination reaction with a higher abundance ratio than thiophenethyl substituents. Compounds such as sufentanil with methoxy substituents at the piperidinyl para-position could produce a large number of fragment ions, which were more susceptible to the rH pathway and loss of methanol neutral molecules, leading to the formation of ions with m/z 355. Similarly, compounds such as remifentanil bearing a methyl formate substituent at the piperidine para-position also produced numerous fragment ions, which were more prone to the rH pathway to lose methyl formate or methanol neutral molecules and furnish fragment ions with m/z 317 or 345. Compounds containing hydroxyl substituents, such as ß-hydroxyfentanyl and ß-hydroxythiofentanyl, produce significant dehydration ions and formed fragment ions with m/z 335 (ß-hydroxyfentanyl) and m/z 341 (ß-hydroxythiofentanyl). A method based on liquid chromatography-quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) for the qualitative and quantitative determination of the 29 fentanyl analogs was developed. Drugs and white powder samples were extracted by acetonitrile, as well as protein and milk beverage samples. Sugar-containing solids or powders, drinking water, fruit and vegetable drinks, health drinks, tea drinks, and alcohol samples were extracted by 10% acetonitrile aqueous solution. Following vortexing, centrifugation, and membrane separation, the target compounds were separated on a Kinetex C18 column (100 mm×2.1 mm, 2.6 µm) with gradient elution at a flow rate of 0.4 mL/min. The mobile phases were composed of acetonitrile and 0.08% formic acid aqueous solution. The target compounds were quantified by LC-QTOF-MS using an external standard method in positive ion mode. The 29 fentanyl analogs showed good linear relationships in the range of 1-20 µg/L, and the correlation coefficients were greater than 0.995. The limits of detection (LODs) and limits of quantification (LOQs) were 0.01 mg/kg and 0.05, respectively. The average recoveries were 85.2%-112.9% for hypoglycemic drugs, Lulu drinks, glucose powder, Zhenlu health drink and chocolate, with RSDs of 1.9%-19.8% (n=6). This method is rapid, simple, time-saving, highly sensitivity and stable, and it is applicable to a wide variety of samples. Hence, it is suitable for the identification, confirmation, and quantitative detection of the 29 fentanyl analogs in drugs, solids or powders containing sugar, beverages, drinking water, wine samples, etc.


Assuntos
Fentanila , Espectrometria de Massas em Tandem , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Verduras
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