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1.
J Agric Food Chem ; 71(43): 16184-16193, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37853551

RESUMO

Leucine, a kind of branched-chain amino acid, plays a regulatory role in the milk production of mammalian mammary glands, but its regulatory functions and underlying molecular mechanisms remain unknown. This work showed that a leucine-enriched mixture (LEUem) supplementation increased the levels of milk protein and milk fat synthesis in primary bovine mammary epithelial cells (BMECs). RNA-seq of leucine-treated BMECs indicated alterations in lipid metabolism, translation, ribosomal structure and biogenesis, and inflammatory response signaling pathways. Meanwhile, the supplementation of leucine resulted in mTOR activation and increased the expression of BCKDHA, FASN, ACC, and SCD1. Interestingly, the expression of PPARα was independently correlated with the leucine-supplemented dose. PPARα activated by WY-14643 caused significant suppression of lipogenic genes expression. Furthermore, WY-14643 attenuated leucine-induced ß-casein synthesis and enhanced the level of BCKDHA expression. Moreover, promoter analysis revealed a peroxisome-proliferator-response element (PPRE) site in the bovine BCKDHA promoter, and WY-14643 promoted the recruitment of PPARα onto the BCKDHA promoter. Together, the present data indicate that leucine promotes the synthesis of ß-casein and fatty acid and that PPARα-involved leucine catabolism is the key target.


Assuntos
Caseínas , PPAR alfa , Bovinos , Animais , Caseínas/genética , Caseínas/metabolismo , Leucina/farmacologia , Leucina/metabolismo , PPAR alfa/genética , PPAR alfa/metabolismo , Glândulas Mamárias Animais/metabolismo , Ácidos Graxos/metabolismo , Células Epiteliais/metabolismo , Mamíferos/metabolismo
2.
Int J Anal Chem ; 2022: 5486290, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35371261

RESUMO

Polyphenols are secondary metabolites of plants and used as effective antioxidants in dietary supplements, whose main sources are fruits, vegetables, and grains. To clarify the content and distribution of polyphenols in different fruit species samples accurately, a rapid and sensitive ultrahigh-pressure liquid chromatography-electrospray ionization-tandem mass spectrometry (UPLC-ESI-MS/MS) method combining dispersive liquid-liquid microextraction (DLLME) was developed for quantitative determination of fifteen polyphenol compounds in fruit juice. In this method, the targets were first extracted from 1 g of fruit juice sample using 10 mL of 80% ethanol solution by ultrasonic-assisted extraction (UAE). Then, 1.0 mL of UAE extracted solution, 60 µL of n-octanol and 2.0 mL of H2O were performed in the following DLLME procedure. A C18 reversed-phase column, ZORBAX SB (100 × 4.6 mm, 3.5 µm), was proposed under gradient elution with 0.1% formic acid aqueous solution and methanol mobile phases for the determination of 15 polyphenols, allowing us to obtain polyphenolic profiles in less than 23.0 min. Under the optimum conditions, the enrichment factors ranged from 162 to 194. The results showed that the 15 polyphenols had linear correlation coefficients (R 2) more than 0.99. The limits of detection (LODs) were between 18.3 and 103.5 ng/g, and the average recoveries were between 96.9 and 116.3% with interday relative standard deviations (RSDs) ranging from 4.4 to 8.2% in all cases. The method was successfully applied to the analysis of real fruit juice samples and presented itself as a simple, rapid, practical, and environment-friendly technique.

3.
Biosens Bioelectron ; 110: 71-77, 2018 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-29602033

RESUMO

This work reports on a molybdenum disulfide (MoS2) based field-effect transistor (FET) biosensor for ultrasensitive label-free detection of DNA via phosphorodiamidate morpholino oligos (PMO)-DNA hybridization. After the chip was fabricated and the sensing channel was modified with positive charges, the negatively charged MoS2 nanosheet was drop-casted onto the channel, enabling MoS2 to tightly bind to the sensing surface via electrostatic interactions. Meanwhile, DNA analogue, PMO, was immobilized on the MoS2 surface, and detection of PMO-DNA hybridization was conducted by the fabricated MoS2 FET biosensor. Due to the neutral character and high affinity of PMO, a limit of detection (LOD) down to 6 fM was obtained, which is lower than that of the previously reported MoS2 FET DNA biosensor based on DNA-DNA hybridization. In addition, the MoS2 FET biosensor also showed high sequence specificity capable of distinguishing the complementary DNA from one-base mismatched DNA, three-base mismatched DNA and noncomplementary DNA. Moreover, the unique FET biosensor was able to detect DNA in complex sample like serum, making the method potential in disease diagnostics.


Assuntos
Técnicas Biossensoriais/instrumentação , DNA/análise , Dissulfetos/química , Molibdênio/química , Morfolinos/química , Hibridização de Ácido Nucleico , Transistores Eletrônicos , DNA/sangue , Desenho de Equipamento , Humanos , Limite de Detecção , Nanoestruturas/química
4.
Int J Antimicrob Agents ; 50(4): 507-511, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28705672

RESUMO

Elizabethkingia meningoseptica, a Gram-negative pathogen once deemed clinically insignificant, tends to cause infections among low-birth-weight infants and immunocompromised patients. Previously, vancomycin was reported to cure several patients with bacteraemia caused by E. meningoseptica. Nevertheless, some laboratory investigations also showed considerable discordance between in vitro vancomycin susceptibility results obtained by the disk diffusion and broth microdilution methods against clinical E. meningoseptica isolates as determined using the criteria for staphylococci recommended by the Clinical and Laboratory Standards Institute (CLSI). In this review, the PubMed database (1960-2017) was searched for studies that reported mainly cases with E. meningoseptica bacteraemia or meningitis treated with vancomycin alone or with regimens that included vancomycin. In addition, the in vitro synergy between vancomycin and other agents against isolates of E. meningoseptica was reviewed. Elizabethkingia meningoseptica bacteraemia appears not to universally respond to intravenous (i.v.) vancomycin-only therapy, especially in patients who require haemodialysis. If i.v. vancomycin is the favoured therapy against E. meningoseptica meningitis, the addition of ciprofloxacin, linezolid or rifampicin might be an option to effectively treat this difficult-to-treat infection. Further clinical studies are needed to determine the clinical efficacy of these combination regimens for the treatment of E. meningoseptica meningitis.


Assuntos
Antibacterianos/uso terapêutico , Bacteriemia/tratamento farmacológico , Infecções por Flavobacteriaceae/tratamento farmacológico , Flavobacteriaceae/efeitos dos fármacos , Meningites Bacterianas/tratamento farmacológico , Vancomicina/uso terapêutico , Bacteriemia/microbiologia , Ciprofloxacina/uso terapêutico , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Sinergismo Farmacológico , Quimioterapia Combinada , Flavobacteriaceae/classificação , Flavobacteriaceae/isolamento & purificação , Infecções por Flavobacteriaceae/microbiologia , Humanos , Hospedeiro Imunocomprometido , Recém-Nascido de Baixo Peso , Recém-Nascido , Linezolida/uso terapêutico , Meningites Bacterianas/microbiologia , Rifampina/uso terapêutico , Resultado do Tratamento
5.
Food Chem ; 213: 260-267, 2016 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-27451180

RESUMO

Gallic acid and its derivatives co-exist with protein components in foodstuffs, but there is few report on their interaction with proteins. On the other hand, plant ferritin represents not only a novel class of iron supplement, but also a new nanocarrier for encapsulation of bioactive nutrients. However, plant ferritin is easy to be degraded by pepsin in the stomach, thereby limiting its application. Herein, we investigated the interaction of gallic acid and its derivatives with recombinant soybean seed H-2 ferritin (rH-2). We found that these phenolic acids interacted with rH-2 in a structure-dependent manner; namely, gallic acid (GA), methyl gallate (MEGA) and propyl gallate (PG) having three HO groups can bind to rH-2, while their analogues with two HO groups cannot. Consequently, such binding largely inhibited ferritin degradation by pepsin. These findings advance our understanding of the relationship between the structure and function of phenolic acids.


Assuntos
Ferritinas/metabolismo , Ácido Gálico/metabolismo , Extratos Vegetais/metabolismo , Sementes/metabolismo , Ácido Gálico/análogos & derivados , Hidroxibenzoatos/metabolismo , Galato de Propila/metabolismo
6.
Sci Rep ; 6: 28018, 2016 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-27301303

RESUMO

Acupuncture treatment is amazing but controversial. Up to now, the mechanism of treating diseases by acupuncture and moxibustion is still unclear, especially the occurrence of the molecular events in local acupoints. Herein, we report an extremely stable microsensor by modifying carbon nanotube (CNT) to the tip surface of acupuncture needle and applying this CNT-modified acupuncture needle for real time monitoring of serotonin (5-HT) in vivo. To stabilize CNT modification on the needle tip surface, poly(3,4-ethylenedioxythiophene)(PEDOT) was employed as glue water to stick CNT on the needle. The detection limit of the CNT-modified needle was found to be approximately 50 nM and 78 nM in the PBS and the cell medium, respectively. In addition, the needle showed good selectivity to some inflammatory mediators and some electroactive molecules. For the first time, the CNT-modified needle could be directly probed into rat body for real time monitoring of 5-HT in vivo, showing a great potential for better understanding the mechanism of acupuncture treatment.


Assuntos
Terapia por Acupuntura/instrumentação , Nanotubos de Carbono/química , Serotonina/análise , Animais , Moxibustão , Ratos , Ratos Wistar
7.
Oncotarget ; 7(27): 41843-41856, 2016 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-27259234

RESUMO

7-hydroxy-5,4'-dimethoxy-2-arylbenzofuran (Ary) is purified from Livistona. It has been demonstrated to have anticancer activity to various tumors in including cervical cancer, but its mechanism is still unclear. In the present, we show that Ary induces cervical cancer cells apoptosis through mitochondria degradation and mediates cervical cancer cell arrest. Further, Ary-inducing cell cycle G1/S-phase arrest is associated with increased cyclin A2 and cyclin dependent kinase 2 (Cdk2) proteins. Knockdown of cyclin A2 using small interfering RNA (siRNA), and inhibiting Cdk2 activity with flavopiridol, strikingly reduced G1/S-phase arrest. Moreover, Ary sustainedly induced phosphorylation of extracellular signal-regulated kinase1/2 (ERK1/2). And ERK1/2 phosphorylation inhibition using specific inhibitor U0126 effectively suppressed cyclin A2 expression, and reduced G1/S-phase arrest induced by Ary. All the experiments in vitro and in vivo verified that Ary has an anticancer effect on cervical cancer. These data provide novel evidences that Ary induces cervical cancer cells apoptosis through mitochondria degradation and cell G1/S-phase arrest. These findings also suggest that ERK-mediated Cdk2/cyclin A signaling pathway is involved in Ary-induced G1/S-phase arrest.


Assuntos
Apoptose/efeitos dos fármacos , Benzofuranos/farmacologia , Ciclina A2/metabolismo , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Proteínas Quinases/metabolismo , Neoplasias do Colo do Útero/tratamento farmacológico , Animais , Benzofuranos/química , Linhagem Celular Tumoral , Quinase 2 Dependente de Ciclina/metabolismo , Feminino , Células HeLa , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Estrutura Molecular , Fitoterapia/métodos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Transdução de Sinais/efeitos dos fármacos , Carga Tumoral/efeitos dos fármacos , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/patologia , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
8.
Sci Rep ; 5: 11627, 2015 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-26112773

RESUMO

We report a unique nanosensing platform by combining modern nanotechnology with traditional acupuncture needle to prepare graphene-modified acupuncture needle (G-AN), and using it for sensitive detection of neurotransmitters via electrochemistry. An electrochemical deposition method was employed to deposit Au nanoparticles (AuNPs) on the tip surface of the traditional acupuncture needle, while the other part of the needle was coated with insulation paste. Subsequently, the G-AN was obtained by cyclic voltammetry reduction of a graphene oxide solution on the surface of the AuNPs. To investigate the sensing property of the G-AN, pH dependence was measured by recording the open circuit potential in the various pH buffer solutions ranging from 2.0 to 10.0. What's more, the G-AN was further used for detection of dopamine (DA) with a limit of detection of 0.24 µM. This novel G-AN exhibited a good sensitivity and selectivity, and could realize direct detection of DA in human serum.


Assuntos
Ouro/química , Grafite/química , Nanopartículas Metálicas/química , Agulhas , Neurotransmissores/análise , Acupuntura/instrumentação , Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Dopamina/análise , Dopamina/sangue , Técnicas Eletroquímicas/instrumentação , Técnicas Eletroquímicas/métodos , Humanos , Concentração de Íons de Hidrogênio , Nanopartículas Metálicas/ultraestrutura , Microscopia Eletrônica de Varredura , Neurotransmissores/sangue , Reprodutibilidade dos Testes
9.
J Nanosci Nanotechnol ; 13(6): 3810-7, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23862412

RESUMO

In this work, we demonstrated a silicon nanowire (SiNW) biosensing platform capable of simultaneously identifying different Dengue serotypes on a single sensing chip. Four peptide nucleic acids (PNAs), specific to each Dengue serotypes (DENV-1 to DENV-4), were spotted on different areas of the SiNW array surface, and the covalently immobilized PNA probes were then interacted with different Dengue serotypes target to establish the specificity of detection. Detection scheme is based on the changes in resistances due to accumulation of negative charges contributed by the hybridized DNA target. The results show that resistance changes only occur in regions where the Dengue target hybridizes with its complementary probe. What is more, a mixture of two different Dengue serotypes obtained from a one-step duplex RT-PCR was applied to the multiplex SiNW surface to validate SiNW capability to identify multiple Dengue serotypes on a single sensing platform. Through this study, we have established the multiplex SiNW biosensor as a promising device to detect multiple Dengue infections with high specificity.


Assuntos
Técnicas Biossensoriais , Vírus da Dengue/isolamento & purificação , Nanofios , Silício , Sequência de Bases , Primers do DNA , Vírus da Dengue/classificação , Reação em Cadeia da Polimerase
10.
Zhen Ci Yan Jiu ; 35(6): 462-6, 2010 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-21375023

RESUMO

OBJECTIVE: To observe the clinical efficacy of acupuncture in the treatment of hypertension patients. METHODS: A total of 80 out-patients and in-patients with primary hypertension were randomly and equally divided into acupuncture group and medication group. Patients of the acupuncture group were treated with acupuncture stimulation of Fengchi (GB20), Qu-chi (LI 11), Taichong (LR 3), etc. for 30 min, combined with Xingjian (LR 2), Xiaxi (GB43) for hyperactivity of the liver-yang, with Ganshu (BL 18) and Fuliu (KI 7) for severe phlegm-damp, and with Guanyuan (CV 4) and Shenshu (BL23) for deficiency of both yin and yang, once per day, continuously for one month except weekends. In addition, patients of the medication group were ordered to take Diovan (80 mg) once daily, continuously for 30 days. Both casual blood pressure (CBP) and ambulatory blood pressure (ABP) were detected by using an auscult-type baumanometer and a dynamic blood monitor, respectively. RESULTS: Of the two 40 cases in the medication and acupuncture groups, 18 (45.0%) and 27 (67.5%) experienced marked improvement in the reduction of blood pressure, 14 (35.0%) and 11 (27.5%) were improved, 8 (20.0%) and 2 (5.0%) failed, with the effective rates being 80.0% and 95.0%, respectively. The therapeutic effect of the acupuncture group was significantly superior to that of medication group in improving hypertension (P < 0.05). CONCLUSION: Acupuncture is superior to Diovan in relieving hypertension.


Assuntos
Terapia por Acupuntura , Hipertensão/terapia , Pontos de Acupuntura , Idoso , Pressão Sanguínea , Feminino , Alemanha , Humanos , Hipertensão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
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