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1.
J Infect Dev Ctries ; 18(1): 168-171, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38377090

RESUMO

INTRODUCTION: Hemorrhagic fever with renal syndrome (HFRS) is a globally prevalent infectious disease caused by the hantavirus in rodents. CASE STUDY: This report describes a case of a 36-year-old male presenting with elevated ferritin, vitamin B12, and folic acid deficiency during the early onset phase of HFRS. Despite normal renal function at admission, the patient exhibited persistent fever and thrombocytopenia, leading to a potential misdiagnosis of an atypical HFRS presentation. Abnormal serum levels of ferritin, vitamin B12, and folic acid served as early indicators of renal dysfunction in patients with HRFS. The patient's condition improved rapidly with a combination of vitamin B6, methyl cobalamin, and folic acid, as evidenced by a subsequent decrease in the ferritin levels, from 3000 to 600 ng/mL, on days 4 and 24, respectively, and an increase in the vitamin B12 and folic acid levels to 200 pg/mL and 36.7 ng/mL, separately. CONCLUSIONS: These findings suggest that ferritin, vitamin B12, and folic acid have the potential to serve as biomarkers for HFRS and play a predictive role in the diagnosis and treatment of the disease.


Assuntos
Ácido Fólico , Febre Hemorrágica com Síndrome Renal , Masculino , Humanos , Adulto , Ferritinas , Vitamina B 12 , Rim
2.
J Vet Pharmacol Ther ; 47(3): 215-225, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38189474

RESUMO

Enrofloxacin (ENR) residues in yellow catfish (Pelteobagrus fulvidraco) often exceed the standard due to excessive use. This study explored the pharmacokinetics of ENR and its metabolite ciprofloxacin (CIP) in yellow catfish following a single dose of 10 mg/kg body weight via intramuscular injection (IM), oral gavage (PO), or a 5-h drug bath at 10 mg/L and 25°C. High-performance liquid chromatography-mass spectrometry was used to determine the ENR and CIP concentrations in various tissues. The highest ENR concentration occurred with IM administration, peaking at 4.124 mg/L in the plasma, 8.359 mg/kg in the kidney, 6.272 mg/kg in the liver, and 5.192 mg/kg in the muscle. However, PO administration resulted in the longest metabolic time, with elimination half-lives of 56.47 h in plasma, 86.43 h in the kidney, 76.25 h in the liver, and 64.75 h in muscle. Additionally, the area under the concentration-time curve values for IM, PO, and bath administration in yellow catfish plasma were 108.36, 88.96, and 22.08 mg·h/L, respectively. These results indicate the effectiveness of all three administration methods in treating bacterial diseases in yellow catfish. The selection of an appropriate administration method depends on the minimal inhibitory concentration of ENR against pathogenic bacteria. Yellow catfish subjected to PO and IM administration require longer resting periods before they can be marketed than those receiving drug bath administration.


Assuntos
Antibacterianos , Peixes-Gato , Enrofloxacina , Animais , Peixes-Gato/metabolismo , Enrofloxacina/farmacocinética , Enrofloxacina/administração & dosagem , Injeções Intramusculares/veterinária , Antibacterianos/farmacocinética , Antibacterianos/administração & dosagem , Antibacterianos/sangue , Administração Oral , Meia-Vida , Área Sob a Curva , Ciprofloxacina/farmacocinética , Ciprofloxacina/administração & dosagem , Ciprofloxacina/sangue
3.
Polymers (Basel) ; 14(19)2022 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-36236167

RESUMO

This study aimed to investigate the mechanical property decay that might occur during actual use and soil burial degradation of bamboo fiber lunch boxes. For this, the effects of three accelerated aging methods, namely damp-heat treatment, freeze-thaw cycle, and artificial weathering cycle, on the tensile strength, dynamic viscoelasticity, and chemical composition of bamboo fiber lunch boxes were compared, and a correlation of their mechanical property decay with soil burial degradation was established to obtain an acceleration factor (SAF) with aging time as a reference. The results showed that the mechanical properties of the bamboo fiber lunch box decreased to different degrees under the three accelerated methods, and the tensile strength decreased to less than 50% after 36 h of damp-heat treatment, 5 freeze-thaw cycles, and 11 artificial weathering cycles. However, after 10 days, the mechanical property of lunch box in soil degradation decreased by more than 50%. Infrared spectroscopy demonstrated rapid hemicellulose degradation during damp-heat treatment and freeze-thaw cycle, as well as a minor quantity of lignin, and a significant amount of lignin under artificial weathering cycle. With the freeze-thaw cycle and the artificial weathering cycle, the relative crystallinity dropped quickly, by 32.3% and 21.5%, respectively, but under damp-heat treatment, the crystallinity dropped barely, by 43.5%. The damage caused by the freeze-thaw cycle to the mechanical properties of bamboo fiber lunch boxes was greater than that by the damp-heat treatment and artificial weathering cycle. The fluctuation of SAF under freeze-thaw cycle was also more drastic. Compared to the artificial weathering cycle, the damp-heat treatment was more stable and reliable in predicting the decay law of soil burial degradation tensile strength of bamboo fiber lunch boxes.

4.
Front Nutr ; 9: 920945, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35938113

RESUMO

Angiotensin I converting enzyme (ACE) inhibitory peptides from fermented foods exhibit great potential to alleviate hypertension. In this study, the peptide extract from Chouguiyu exhibited a good inhibition effect on ACE, and the inhibition rate was significantly enhanced after fermentation for 8 days. The ACE inhibitory peptides were further identified, followed by their inhibition and formation mechanisms using microbiome technology and molecular docking. A total of 356 ACE inhibitory peptides were predicted using in silico, and most ACE inhibitory peptides increased after fermentation. These peptides could be hydrolyzed from 94 kinds of precursor proteins, mainly including muscle-type creatine kinase, nebulin, and troponin I. P1 (VEIINARA), P2 (FAVMVKG), P4 (EITWSDDKK), P7 (DFDDIQK), P8 (IGDDPKF), P9 (INDDPKIL), and P10 (GVDNPGHPFI) were selected as the core ACE inhibitory peptides according to their abundance and docking energy. The salt bridge and conventional hydrogen bond connecting unsaturated oxygen atoms in the peptides contributed most to the ACE inhibition. The cleavage proteases from the microbial genera in Chouguiyu for preparing these 7 core ACE inhibitory peptides were further analyzed by hydrolysis prediction and Pearson's correlation. The correlation network showed that P7, P8, and P9 were mainly produced by the proteases from LAB including Lactococcus, Enterococcus, Vagococcus, Peptostreptococcus, and Streptococcus, while P1, P2, P4, and P10 were mainly Produced by Aeromonas, Bacillus, Escherichia, and Psychrobacter. This study is helpful in isolating the proteases and microbial strains to directionally produce the responding ACE inhibitory peptides.

5.
J Food Sci ; 85(6): 1699-1706, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32458467

RESUMO

The eight biogenic amines (BA), which are histamine (HIS), tryptamine, putrescine, 2-phenylethylamine, cadaverine, tyramine, spermidine, and spermine, were determined in Chub Mackerel under different storage conditions after being freshly caught. The storage time and temperature were varied and the guts either present or removed. This study describes a reverse-phase high-performance liquid chromatography (HPLC) with a fluorescence detector following precolumn derivation with dansyl chloride method for the determination of BA in in Chub Mackerel samples. HIS represented the highest content of BA regardless of the storage temperature and time. During a 24-hr period, the content of HIS reached its highest level of 6,466.63 mg/kg at the storage temperature of 30 °C, whereas it only reached 28.73 mg/kg in 24 hr when the storage temperature was 0 °C, which is way below the standard acceptable threshold level (400 mg/kg). The storage times for the content of HIS to exceed the standard threshold level for HIS at different storage temperatures of 0, 4, 10, 15, 20, and 25 °C were 12, 5, 4 days, 48, 36, 15, and 14 hr, respectively. However, these times were significantly shortened when the viscera was removed from freshly-caught fish before storage. This study not only provides data for monitoring the content of BA, especially HIS, to ensure the safe storage and consumption of freshly-caught Chub Mackerel, but also presents a cost-effective method to extend the storage time of freshly-caught Chub Mackerel. PRACTICAL APPLICATION: This study not only provides data for monitoring the content of BA, especially HIS, to ensure the safe storage and consumption of freshly-caught Chub Mackerel, but also presents a cost-effective method, which is gut-removal during storage, to extend the storage time of freshly-caught Chub Mackerel.


Assuntos
Aminas Biogênicas/análise , Armazenamento de Alimentos/métodos , Carne/análise , Animais , Cadaverina/análise , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia de Fase Reversa , Histamina/análise , Perciformes
6.
Food Chem ; 301: 125265, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31387046

RESUMO

A novel method for determination of triazole fungicides and their enantiomers in foods was developed by aqueous two-phase extraction (ATPE) coupled with two-dimensional liquid chromatography (2D-LC). With an aqueous two-phase system (ATPS) of ethanol/K2HPO4 as biphasic extractant, the effects of the ATPS composition, extraction temperature and time on extraction yields of triazole fungicides were investigated. Optimum conditions were concluded as follows: ethanol concentration 31% (w/w) and K2HPO4 concentration 21% (w/w), extraction temperature 60 °C, extraction time 21 min. Based on reversed-phase separation systems, a 2D-LC was constructed by optimizing chromatographic conditions and online heart-cutting procedures. As a result, eight triazole fungicides and their enantiomers were separated respectively on C18 and cellulose-tris (3,5-dimethylphenylcarbamate) stationary phases, revealing good linear relationship in the range of 0.1218-30.06 µg/mL (R2 ≥ 0.9984). The detection limits and recoveries were 0.03113-0.3525 µg/mL and 71.57-107.8%, respectively. The ATPE-2D-LC method was successfully applied to chiral analysis of triazole fungicides in fruits and vegetables.


Assuntos
Cromatografia Líquida/métodos , Frutas/química , Fungicidas Industriais/análise , Extração Líquido-Líquido/métodos , Triazóis/análise , Verduras/química , Fungicidas Industriais/química , Fungicidas Industriais/isolamento & purificação , Limite de Detecção , Estereoisomerismo , Triazóis/química , Triazóis/isolamento & purificação
7.
Org Biomol Chem ; 17(34): 7854-7857, 2019 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-31408075

RESUMO

A copper-catalyzed DTBP oxidative dual C-H sulfurization has been developed for the direct thiocarbamation of imidazopyridines using a combination of elemental sulfur and formamides as carbamothioyl surrogates. NBS (bromo succinimide) was found to promote the thiocarbamation in good yields. This dual C-H sulfurization strategy enables access to a wide range of carbamothioyl imidazoheterocycles without the use of highly toxic phosgene.

8.
Org Lett ; 21(2): 545-548, 2019 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-30596506

RESUMO

A sulfite-promoted transformation of azoles into N-difluoromethylthioureas through N-difluoromethylation and sulfuration has been developed. In this reaction, inexpensive ethyl bromodifluoroacetate and nontoxic elemental sulfur were used as the difluoromethylation and sulfuration reagents, respectively. A variety of azoles, including benzimidazoles, imidazoles, and triazoles, performed well to afford a broad range of azole thioureas in moderate to good yields.

9.
Biomed Chromatogr ; 32(7): e4223, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29495074

RESUMO

A highly sensitive method was developed for the analysis of short-chain perfluorinated alkyl acids (PFAAs) in serum samples using solid-phase extraction (SPE) coupled with ion chromatography-electrospray ionization-mass spectrometry. The synthesized amino-functionalized graphene oxide nanocomposites were used as an SPE sorbent for the enrichment of trace analytes and purification of samples. They exhibited high selectivity to polar compounds. The suppressor was employed to remove counterions and reduce background signals of mobile phase. These two crucial steps could effectively eliminate matrix effects and enhance analytical sensitivity. The lowest limits of quantification were 2.0 µg L-1 for perfluorobutanoic acid and perfluorovaleric acid, 1.0 µg L-1 for perfluorocaproic acid and 0.50 µg L-1 for perfluorobutane sulfonic acid, respectively. The procedure was successfully applied for determination of trace PFAAs in 25 serum samples. Mean recoveries ranged from 86.3 to 101.4% with relative standard deviations of 1.6-6.8%. The method allowed an excellent separation and quantification of short-chain PFAAs that were difficult to analyze by conventional chromatography.


Assuntos
Cromatografia por Troca Iônica/métodos , Fluorocarbonos/sangue , Grafite/química , Nanocompostos/química , Extração em Fase Sólida/métodos , Humanos , Modelos Lineares , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrometria de Massas por Ionização por Electrospray
10.
Chem Commun (Camb) ; 53(55): 7784-7787, 2017 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-28650506

RESUMO

Dual C-H thiolation reactions using elemental sulphur remain a challenge. This communication discloses an oxidative radical dual sp2/sp3 C-H thiolation strategy for the coupling of imidazopyridines with ethers or alkanes using elemental sulphur.

11.
Chem Commun (Camb) ; 53(45): 6073-6076, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-28480912

RESUMO

The Langlois reagent was found to be effective for the isothiocyanation of primary amines in the presence of copper iodide and diethyl phosphonate.

12.
J Sep Sci ; 39(12): 2356-64, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27121404

RESUMO

In this work, a magnetic metal-organic framework designated as MIL-100(Fe) was prepared and applied as a magnetic solid-phase extraction sorbent for the determination of trace polycyclic aromatic hydrocarbons in environmental water samples by coupling with high-performance liquid chromatography and fluorescence detection. The magnetic microspheres exhibited large surface areas and high extraction ability, making them excellent candidates as sorbents for enrichment of trace polycyclic aromatic hydrocarbons. Under the optimized experimental conditions, good sensitivity levels were achieved with low detection limits ranging from 32 to 2110 pg/mL and good linearities with correlation coefficients higher than 0.9990 for the investigated 13 polycyclic aromatic hydrocarbons. The proposed method has been validated in the analysis of real water samples with mean recoveries in the range of 81.4-126.9% at four spiked levels and the relative standard deviations in the range of 1.3-17.0%. The magnetic MIL-100(Fe) microspheres were stable enough for 150 extractions without a significant loss of extraction performance.

13.
Anal Chim Acta ; 888: 75-84, 2015 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-26320961

RESUMO

A carboxylated graphene oxide/polyvinyl chloride (CGO/PVC) material was prepared as a sorbent for the selective extraction of sulphonamides from complex sample. After being dispersed in buffer solution, sample was transferred into the prefabricated solid-phase extraction (SPE) column, which integrated extraction and cleanup into one single-step. A multi-response optimization based on the Box-Behnken design was used to optimize factors affecting extraction efficiency. Compared with the commonly commercial sorbents including MCX, WCX and C18, CGO/PVC hybrid material had higher extraction selectivity and capacity to sulphonamides. The limits of detection and quantification for seven target compounds were in the range of 3.4-7.1 µg/L and 11.4-23.7 µg/L, respectively. The self-assembly SPE cartridge was successfully used to enrich seven analytes in anti-acne cosmetics prior to ion chromatography detection with good recoveries of 87.8-102.0% and relative standard deviations of 1.2-6.4%, implying that this method was suitable for routine analysis of cosmetics.


Assuntos
Cosméticos/análise , Grafite/química , Óxidos/química , Cloreto de Polivinila/química , Extração em Fase Sólida/métodos , Sulfonamidas/isolamento & purificação , Cromatografia por Troca Iônica/métodos , Limite de Detecção
14.
Phytochem Anal ; 20(6): 498-502, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19742782

RESUMO

INTRODUCTION: Dehydrocavidine is a major component of Corydalis saxicola Bunting with sedative, analgesic, anticonvulsive and antibacterial activities. Conventional methods have disadvantages in extracting, separating and purifying dehydrocavidine from C. saxicola. Hence, an efficient method should be established. OBJECTIVE: To develop a suitable preparative method in order to isolate dehydrocavidine from a complex C. saxicola extract by preparative HSCCC. METHODOLOGY: The methanol extract of C. saxicola was prepared by optimised microwave-assisted extraction (MAE). The analytical HSCCC was used for the exploration of suitable solvent systems and the preparative HSCCC was used for larger scale separation and purification. Dehydrocavidine was analysed by high-performance liquid chromatography (HPLC) and further identified by ESI-MS and 1H NMR. RESULTS: The optimised MAE experimental conditions were as follows: extraction temperature, 60 degrees C; ratio of liquid to solid, 20; extraction time, 15 min; and microwave power, 700 W. In less than 4 h, 42.1 mg of dehydrocavidine (98.9% purity) was obtained from 900 mg crude extract in a one-step separation, using a two-phase solvent system composed of chloroform-methanol-0.3 m hydrochloric acid (4 : 0.5 : 2, v/v/v). CONCLUSION: Microwave-assisted extraction coupled with high-speed counter-current chromatography is a powerful tool for extraction, separation and purification of dehydrocavidine from C. saxicola.


Assuntos
Alcaloides de Berberina/isolamento & purificação , Corydalis/química , Distribuição Contracorrente/métodos , Micro-Ondas , Cromatografia Líquida de Alta Pressão/métodos , Espectroscopia de Ressonância Magnética , Espectrometria de Massas por Ionização por Electrospray
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