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1.
Nature ; 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38776963

RESUMEN

Bitter taste receptors, particularly TAS2R14, play central roles in discerning a wide array of bitter substances, ranging from dietary components to pharmaceutical agents1,2. TAS2R14 is also widely expressed in extragustatory tissues, suggesting its extra roles in diverse physiological processes and potential therapeutic applications3. Here we present cryogenic electron microscopy structures of TAS2R14 in complex with aristolochic acid, flufenamic acid and compound 28.1, coupling with different G-protein subtypes. Uniquely, a cholesterol molecule is observed occupying what is typically an orthosteric site in class A G-protein-coupled receptors. The three potent agonists bind, individually, to the intracellular pockets, suggesting a distinct activation mechanism for this receptor. Comprehensive structural analysis, combined with mutagenesis and molecular dynamic simulation studies, elucidate the broad-spectrum ligand recognition and activation of the receptor by means of intricate multiple ligand-binding sites. Our study also uncovers the specific coupling modes of TAS2R14 with gustducin and Gi1 proteins. These findings should be instrumental in advancing knowledge of bitter taste perception and its broader implications in sensory biology and drug discovery.

2.
Nature ; 619(7968): 73-77, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37316660

RESUMEN

High-entropy alloy nanoparticles (HEA-NPs) show great potential as functional materials1-3. However, thus far, the realized high-entropy alloys have been restricted to palettes of similar elements, which greatly hinders the material design, property optimization and mechanistic exploration for different applications4,5. Herein, we discovered that liquid metal endowing negative mixing enthalpy with other elements could provide a stable thermodynamic condition and act as a desirable dynamic mixing reservoir, thus realizing the synthesis of HEA-NPs with a diverse range of metal elements in mild reaction conditions. The involved elements have a wide range of atomic radii (1.24-1.97 Å) and melting points (303-3,683 K). We also realized the precisely fabricated structures of nanoparticles via mixing enthalpy tuning. Moreover, the real-time conversion process (that is, from liquid metal to crystalline HEA-NPs) is captured in situ, which confirmed a dynamic fission-fusion behaviour during the alloying process.

3.
J Am Chem Soc ; 146(11): 7118-7123, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38437170

RESUMEN

High-entropy oxides (HEOs) with an ultrathin geometric structure are especially expected to exhibit extraordinary performance in different fields. The phase structure is deemed as a key factor in determining the properties of HEOs, rendering their phase control synthesis tempting. However, the disparity in intrinsic phase structures and physicochemical properties of multiple components makes it challenging to form single-phase HEOs with the target phase. Herein, we proposed a self-lattice framework-guided strategy to realize the synthesis of ultrathin HEOs with desired phase structures, including rock-salt, spinel, perovskite, and fluorite phases. The participation of the Ga assistor was conducive to the formation of the high-entropy mixing state by decreasing the formation energy. The as-prepared ultrathin spinel HEOs were demonstrated to be an excellent catalyst with high activity and stability for the oxygen evolution reaction in water electrolysis. Our work injects new vitality into the synthesis of HEOs for advanced applications and undoubtedly expedites their phase engineering.

4.
Int Orthop ; 48(2): 547-553, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37782331

RESUMEN

PURPOSE: The search for more effective and safe treatment methods for cervical spondylotic radiculopathy (CSR) has led to the rapid development and increasing popularity of minimally invasive posterior cervical foraminotomy (MI-PCF). This study aims to compare two important approaches for MI-PCF surgery: the channel-assisted cervical key hole technology combined with ultrasonic bone osteotome (CKH-UBO) and posterior percutaneous endoscopic cervical foraminotomy (PPECF). METHODS: Data from patients treated with single-level CKH-UBO (n = 35) or PPECF (n = 40) were analyzed. Clinical outcomes, including visual analogue scale (VAS) scores for neck and arm pain, Neck Disability Index (NDI), and modified Macnab criteria, were assessed preoperatively, as well as at three days, three months, and one year postoperatively. RESULTS: The percentages of patients with excellent and good outcomes were 97.14% and 92.5%, respectively. The average surgical time in the CKH-UBO group was significantly shorter than in the PPECF group (p < 0.001), while the average incision length in the PPECF group was significantly smaller than in the CKH-UBO group. There were no significant differences between the two groups in terms of blood loss, hospital stay, and clinical outcomes at three days, three months, and 12 months postoperatively. CONCLUSION: CKH-UBO can achieve the same surgical outcomes as PPECF for the treatment of CSR. However, CKH-UBO saves more time but requires patients to undergo larger incisions.


Asunto(s)
Foraminotomía , Radiculopatía , Espondilosis , Humanos , Foraminotomía/efectos adversos , Foraminotomía/métodos , Estudios Retrospectivos , Ultrasonido , Resultado del Tratamiento , Vértebras Cervicales/diagnóstico por imagen , Vértebras Cervicales/cirugía , Espondilosis/cirugía , Radiculopatía/cirugía , Discectomía/métodos
5.
World J Surg Oncol ; 21(1): 181, 2023 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-37337182

RESUMEN

BACKGROUND: This study investigated the clinicopathological features, immunophenotypic characteristics and differential diagnosis of primary breast carcinomas with signet ring cell differentiation, as well as differences in the traits of signet ring-like cell mucin. METHODS: A total of five cases of primary breast cancer diagnosed with signet ring cell differentiation and treated at The First People's Hospital of Jingmen from January 2016 to December 2021 were collected. HE, immunohistochemical staining, and AB-PAS staining were used for the analysis. RESULTS: Although we strictly selected all the primary breast cancer cases with signet ring cell differentiation, there were differences in the arrangement of the cells and the grading of nuclei. Our immunohistochemical results showed that the ER was consistently strongly positive, and the PR expression was not consistent, while all the cases of HER2 were negative. CK7 was negative in one case, and CK20 and CK5/6 were not expressed in all the cases. The mucin MUC1 was positive and showed two patterns. MUC2 was strongly positive in all the cases. All the cases were negative for CDX2, SATB2, PAX8, TTF-1, and Napsin A, while the positive expression of COX2, Villin, and WT-1 was not constant. One case expressed neuroendocrine markers. The expression level of Ki67 was between 10 and 30%. AB (pH 2.5)-PAS staining revealed that the intracellular mucus contained more cells with neutral mucus, while the extracellular mucus was mainly acidic. CONCLUSION: We found that histological morphology, cell morphology, and nuclear grading differentiate among different cases. The immunohistochemical characteristics of primary breast cancers diagnosed with signet ring cell differentiation are helpful for identification. The differences in the expression patterns of mucins may be related to unfavorable clinicopathological factors, but their usefulness as a prognostic marker remains to be further understood. The heterogeneity of cell mucus, the differentiation of tumor cells, and the phenotypic changes of tumors also need further study.


Asunto(s)
Neoplasias de la Mama , Carcinoma de Células en Anillo de Sello , Humanos , Femenino , Biomarcadores de Tumor/metabolismo , Carcinoma de Células en Anillo de Sello/diagnóstico , Diferenciación Celular , Mucinas , Neoplasias de la Mama/patología
6.
BMC Musculoskelet Disord ; 24(1): 81, 2023 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-36721172

RESUMEN

PURPOSE: To explore the clinical efficacy and operation points of cervical radiculopathy with osseous foraminal stenosis treated with ultrasonic osteotome in anterior cervical surgery. METHODS: From January 2018 to June 2021,a retrospective analysis of 23 patients with cervical radiculopathy with bony foraminal stenosis during this period was retrospectively analyzed. Anterior Cervical Discectomy and Fusion (ACDF) was used for all cases in this group. Intraoperative use of ultrasonic osteotome to decompress the nerve in the intervertebral foramina. The operation time, intraoperative blood loss and complication rate were recorded in this group of patients. Interbody fusion was evaluated using Brantigan criteria. The IC-PACS imaging system was used to measure the intervertebral foramen area (IFA) before and after surgery to evaluate the range of decompression. The VAS (Visual Analogue Scale, VAS) score and NDI (Neck Disability Index, NDI) score before and after surgery were recorded to evaluate the clinical efficacy. RESULTS: All enrolled patients were followed up regularly for 1 year or more. The mean operative time was 61.5 ± 8.0 minutes. The average intraoperative blood loss was 88.3 ± 12.8 ml, and the average hospital stay was 8.1 ± 1.7d. Twenty one cases of successful fusion were followed up 1 year after operation, and the fusion rate was 91.3%. IFA expanded from 25.1 ± 4.0 mm2 before operation to 57.9 ± 3.4 mm2 at 1 year after operation, and the difference was statistically significant (P < 0.001). The VAS score and NDI score of patients 3 days after surgery, 3 months after surgery, and 1 year after surgery were significantly lower than those before surgery (P < 0.001). There was 1 case of dysphagia and 1 case of Cage subsidence after operation, and the complication rate was 8.6%. CONCLUSION: Anterior cervical surgery using ultrasonic osteotome in the treatment of cervical radiculopathy with bony foraminal stenosis has reliable clinical efficacy and high safety, and is worthy of clinical promotion.


Asunto(s)
Radiculopatía , Espondilosis , Humanos , Radiculopatía/diagnóstico por imagen , Radiculopatía/etiología , Radiculopatía/cirugía , Estudios Retrospectivos , Ultrasonido , Pérdida de Sangre Quirúrgica , Constricción Patológica , Espondilosis/complicaciones , Espondilosis/diagnóstico por imagen , Espondilosis/cirugía
7.
J Basic Microbiol ; 63(5): 499-518, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36782108

RESUMEN

Since African swine fever virus (ASFV) replication is closely related to its host's machinery, codon usage of viral genome can be subject to selection pressures. A better understanding of codon usage can give new insights into viral evolution. We implemented information entropy and revealed that the nucleotide usage pattern of ASFV is significantly associated with viral isolation factors (region and time), especially the usages of thymine and cytosine. Despite the domination of adenine and thymine in the viral genome, we found that mutation pressure alters the overall codon usage pattern of ASFV, followed by selective forces from natural selection. Moreover, the nucleotide skew index at the gene level indicates that nucleotide usages influencing synonymous codon bias of ASFV are significantly correlated with viral protein hydropathy. Finally, evolutionary plasticity is proved to contribute to the weakness in synonymous codons with A- or T-end serving as optimal codons of ASFV, suggesting that fine-tuning translation selection plays a role in synonymous codon usages of ASFV for adapting host. Taken together, ASFV is subject to evolutionary dynamics on nucleotide selections and synonymous codon usage, and our detailed analysis offers deeper insights into the genetic characteristics of this newly emerging virus around the world.


Asunto(s)
Virus de la Fiebre Porcina Africana , Uso de Codones , Animales , Porcinos , Virus de la Fiebre Porcina Africana/genética , Nucleótidos/genética , Timina , Evolución Molecular , Codón , Genómica , Sesgo
8.
Sensors (Basel) ; 23(20)2023 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-37896507

RESUMEN

PbS films grown on quartz substrates by the chemical bath deposition method were annealed in an O2 atmosphere to investigate the role of oxygen in the sensitization process at different annealing temperatures. The average grain size of the PbS films gradually increased as the annealing temperature increased from 400 °C to 700 °C. At an annealing temperature of 650 °C, the photoresponsivity and detectivity reached 1.67 A W-1 and 1.22 × 1010 cm Hz1/2 W-1, respectively. The role of oxides in the sensitization process was analyzed in combination with X-ray diffraction and scanning electron microscopy results, and a three-dimensional network model of the sensitization mechanism of PbS films was proposed. During the annealing process, O functioned as a p-type impurity, forming p+-type PbS layers with high hole concentrations on the surface and between the PbS grains. As annealing proceeds, the p+-type PbS layers at the grain boundaries interconnect to form a three-dimensional network structure of hole transport channels, while the unoxidized p-type PbS layers act as electron transport channels. Under bias, photogenerated electron-hole pairs were efficiently separated by the formed p+-p charge separation junction, thereby reducing electron-hole recombination and facilitating a higher infrared response.

9.
Nano Lett ; 22(16): 6692-6699, 2022 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-35939782

RESUMEN

We report the monolithic fabrication of twin microtube cavities by a nanomembrane origami method for achieving collective coupling of 3D confined optical modes. Owing to the well-aligned twin geometries, two sets of 3D confined optical modes in twin microtubes are spectrally and spatially matched, by which both the fundamental and higher-order axial modes are respectively coupled with each other. Multiple groups of the coupling modes provide multiple effective channels for energy exchange between coupled microcavities illustrated by the measured spatial optical field distributions. The spectral anticrossing and changing-over features of each group of coupled modes are revealed in experiments and calculations, indicating the occurrence of strong coupling. In addition, the simulated 3D mode profiles of twin microcavities confirm the collective strong coupling behavior, which shows good agreement with experiments. The collective coupling of 3D confined resonant modes promises broad applications in multichannel optical signal processing, nanophotonics, and 3D non-Hermitian systems.

10.
Environ Geochem Health ; 45(12): 9583-9598, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37773482

RESUMEN

Evidence shows the relationships of individual environmental PAHs by their urinary metabolites with relative telomere length (RTL), which may be affected by biological gender differences. Since plasma parent PAHs are not metabolized, it may reflect human exposure to PAHs more realistically in daily life. Thus, exploring joint associations between plasma parent PAHs and RTL is urgent, which may identify the major contributor to its adverse effect. In this study, 2577 participants were obtained from the Henan Rural Cohort. The level of PAHs in blood samples was detected by gas chromatography coupled with tandem mass spectrometry. RTL in blood samples was detected by quantitative polymerase chain reaction. Generalized linear models or quantile g-computation were performed to evaluate the associations between the individual or a mixture of PAHs and RTL. Results from generalized linear models showed that each unit increment in BghiP value corresponded to a 0.098 (95%CI: 0.067, 0.129) increment in RTL for men; each unit increment in BaP, BghiP and Flu value corresponded to a 0.041 (95%CI: 0.014, 0.068), 0.081 (95%CI: 0.055, 0.107) and 0.016 (95%CI: 0.005, 0.027) increment in RTL for women. Results from quantile-g computation revealed that each one-quantile increment in the mixture of 10 PAHs corresponded to a 0.057 (95%CI: 0.021, 0.094) and 0.047 (95%CI: 0.003, 0.091) increment in RTL values of women and men, but these associations were mainly ascribed to three PAHs for women (BaP, Flu and BghiP) and men (BaP, BghiP and Pyr), respectively. Similar results were found in smoking men and cooking women without smoking. Our study found that exposure to 10 PAHs mixture was positively associated with RTL across gender, mainly attributed to Flu, BaP and BghiP, implicating that gender-specific associations may be ascribed to tobacco and cooking smoke pollution. The findings provided clues for effective measures to control PAHs pollutants-related aging disease.Clinical trial registration The Henan Rural Cohort Study has been registered at the Chinese Clinical Trial Register (Registration number: ChiCTR-OOC-15006699). Date of registration: 06 July 2015. http://www.chictr.org.cn/showproj.aspx?proj=11375 .


Asunto(s)
Contaminantes Ambientales , Hidrocarburos Policíclicos Aromáticos , Masculino , Humanos , Femenino , Hidrocarburos Policíclicos Aromáticos/análisis , Estudios de Cohortes , Cromatografía de Gases y Espectrometría de Masas , Contaminantes Ambientales/toxicidad , Contaminantes Ambientales/análisis , Telómero/química
11.
Biochem Genet ; 60(1): 80-93, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34100175

RESUMEN

Rwanda is one of the smallest countries of Africa, where forensic genetic studies are rarely being conducted and very few DNA databases have been developed. Short tandem repeats (STRs) polymorphisms were investigated in 505 unrelated Rwandese by using the HUMDNA TYPING (Yanhuang) Kit. The following STRs were targeted: D3S1358, D13S317, D7S820, D16S539, SE33, D10S1248, D5S818, D21S11, TPOX, D1S1656, D6S1043, D19S433, D22S1045, D8S1179, Penta E, D2S441, D12S391, D2S1338, vWA, Penta D, TH01, D18S51, CSF1PO and FGA. The purpose of this study was to elucidate the genetic diversity and explore the potential of applying these 24 STR in 505 Rwandan population in forensics. A total of 360 alleles, with corresponding allele frequencies in the range from 0.001 to 0.442, were found in the Rwandan population. SE33 presented the highest polymorphism (PIC=0.921) among these 24 loci, whereas D13S317 presented the lowest one (PIC=0.671). No deviation from the Hardy-Weinberg equilibrium was observed for any of the 24 loci. The forensic parameters, including the combined power of discrimination (PD and the combined exclusion power, have demonstrated that this panel of 24 STRs is highly informative and useful for forensic applications such as individuals' identification and paternity tests. Additionally, the genetic distances between Rwanda population and other 24 published populations were calculated based on 8 overlapping loci with the polygenetic tree revealing significant clusters in the populations associated with their geographic locations and their historical relationship.


Asunto(s)
Genética de Población , Repeticiones de Microsatélite , Dermatoglifia del ADN , Frecuencia de los Genes , Humanos , Polimorfismo Genético , Rwanda
12.
Ecotoxicol Environ Saf ; 247: 114254, 2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-36334344

RESUMEN

Cadmium ion (Cd2+) exposure has been reported to associate with the prevalence of dyslipidemia, and contribute to the initiation and progression of nonalcoholic fatty liver disease (NAFLD). However, Cd2+ exposure perturbed specific metabolic pathways and underlying mechanisms are still unclear. In the present study, through lipidomics analyses of differential metabolites in serum between the Cd2+-exposed mice and the control group, 179 differential metabolites were identified, among which phosphatidylcholines (PCs) accounted for 49 % metabolites. Moreover, the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment assay indicates that PCs participate in the metabolic pathways, including the Arachidonic Acid (AA) metabolism, which also could be potential NAFLD biomarkers. Moreover, in vivo and in vitro results suggested that Cd2+ exposure induced PC synthesis and remodeling, and increased AA level by promoting fatty acid desaturase 1 (FADS1) to catalyze synthesis process instead of cytosolic phospholipase A2 (cPLA2) mediated release pathway. Inhibition of FADS1 by T3364366 could reverse Cd-induced AA, prostaglandin E2 (PGE2) and triglyceride (TAG) levels, and it also reduce cisplatin resistance in HepG2 cells. This study provides new evidence of Cd2+-induced dyslipidemia and reveals underlying molecular mechanism involved in liver dysfunction of Cd2+ exposure.


Asunto(s)
Enfermedad del Hígado Graso no Alcohólico , Fosfatidilcolinas , Ratones , Animales , Ácido Araquidónico , Cadmio/toxicidad , Metabolismo de los Lípidos , delta-5 Desaturasa de Ácido Graso
13.
Microb Cell Fact ; 20(1): 217, 2021 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-34863154

RESUMEN

BACKGROUND: Endophytic actinomycetes, as emerging sources of bioactive metabolites, have been paid great attention over the years. Recent reports demonstrated that endophytic streptomycetes could yield compounds with potent anticancer properties that may be developed as chemotherapeutic drugs. RESULTS: Here, a total of 15 actinomycete-like isolates were obtained from the root tissues of Lilium davidii var. unicolor (Hoog) Cotton based on their morphological appearance, mycelia coloration and diffusible pigments. The preliminary screening of antagonistic capabilities of the 15 isolates showed that isolate LRE541 displayed antimicrobial activities against all of the seven tested pathogenic microorganisms. Further in vitro cytotoxicity test of the LRE541 extract revealed that this isolate possesses potent anticancer activities with IC50 values of 0.021, 0.2904, 1.484, 4.861, 6.986, 8.106, 10.87, 12.98, and 16.94 µg/mL against cancer cell lines RKO, 7901, HepG2, CAL-27, MCF-7, K562, Hela, SW1990, and A549, respectively. LRE541 was characterized and identified as belonging to the genus Streptomyces based on the 16S rRNA gene sequence analysis. It produced extensively branched red substrate and vivid pink aerial hyphae that changed into amaranth, with elliptic spores sessile to the aerial mycelia. To further explore the mechanism underlying the decrease of cancer cell viability following the LRE541 extract treatment, cell apoptosis and cell cycle arrest assays were conducted in two cancer cell lines, RKO and 7901. The result demonstrated that LRE541 extract inhibited cell proliferation of RKO and 7901 by causing cell cycle arrest both at the S phase and inducing apoptosis in a dose-dependent manner. The chemical profile of LRE541 extract performed by the UHPLC-MS/MS analysis revealed the presence of thirty-nine antitumor compounds in the extract. Further chemical investigation of the LRE541 extract led to the discovery of one prenylated indole diketopiperazine (DKP) alkaloid, elucidated as neoechinulin A, a known antitumor agent firstly detected in Streptomyces; two anthraquinones 4-deoxy-ε-pyrromycinone (1) and epsilon-pyrromycinone (2) both displaying anticancer activities against RKO, SW1990, A549, and HepG2 with IC50 values of 14.96 ± 2.6 - 20.42 ± 4.24 µg/mL for (1); 12.9 ± 2.13, 19.3 ± 4.32, 16.8 ± 0.75, and 18.6 ± 3.03 µg/mL for (2), respectively. CONCLUSION: Our work evaluated the anticarcinogenic potential of the endophyte, Streptomyces sp. LRE541 and obtained one prenylated indole diketopiperazine alkaloid and two anthraquinones. Neoechinulin A, as a known antitumor agent, was identified for the first time in Streptomyces. Though previously found in Streptomyces, epsilon-pyrromycinone and 4-deoxy-ε-pyrromycinone were firstly shown to possess anticancer activities.


Asunto(s)
Antineoplásicos/aislamiento & purificación , Antineoplásicos/farmacología , Endófitos/química , Lilium/microbiología , Streptomyces/química , Streptomyces/genética , Actinobacteria , Antineoplásicos/química , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células HeLa , Humanos , Filogenia , Raíces de Plantas/microbiología , ARN Ribosómico 16S/genética , Espectrometría de Masas en Tándem
14.
Int J Med Sci ; 18(12): 2705-2715, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34104103

RESUMEN

The therapeutic effect of dihydroartemisinin (DHA) against cutaneous squamous cell carcinoma (cSCC) has been previously demonstrated; however, the underlying mechanism remains unclear. This study sought to verify the therapeutic effect of DHA against cSCC and explore its underlying mechanism in A431 cSCC cells. This study reported that DHA inhibited A431 cells proliferation in a time- and concentration-dependent manner and promoted A431 cells apoptosis. Moreover, DHA inhibited the invasion and migration of A431 cells. Mechanistically, DHA promoted autophagy and inhibited activation of the absent in melanoma 2 (AIM2) inflammasome pathway and NF-κB/HIF-1α/VEGF pathway. Treatment of A431 cells with the mTOR inhibitor, and autophagy promoter, rapamycin also inhibited these two pathways. In conclusion, DHA inhibited activation of the AIM2 inflammasome pathway and NF-κB/HIF-1α/VEGF pathway by promoting autophagy in A431 cells, thus accounting for its therapeutic effect. Induction of autophagy by DHA may be mediated by inhibiting the mTOR pathway and promoting reactive oxygen species production.


Asunto(s)
Artemisininas/farmacología , Carcinoma de Células Escamosas/tratamiento farmacológico , Inflamasomas/efectos de los fármacos , Neoplasias Cutáneas/tratamiento farmacológico , Apoptosis/efectos de los fármacos , Apoptosis/inmunología , Artemisininas/uso terapéutico , Autofagia/efectos de los fármacos , Autofagia/inmunología , Carcinoma de Células Escamosas/inmunología , Carcinoma de Células Escamosas/patología , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Movimiento Celular/inmunología , Proliferación Celular/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Inflamasomas/inmunología , Inflamasomas/metabolismo , FN-kappa B/metabolismo , Transducción de Señal/efectos de los fármacos , Transducción de Señal/inmunología , Sirolimus/farmacología , Sirolimus/uso terapéutico , Neoplasias Cutáneas/inmunología , Neoplasias Cutáneas/patología , Serina-Treonina Quinasas TOR/antagonistas & inhibidores , Serina-Treonina Quinasas TOR/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo
15.
J Sep Sci ; 44(18): 3506-3515, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34268859

RESUMEN

We wanted to explore a new method for the determination of monosaccharides in Polygonatum cyrtonema Hua polysaccharide using the ultra-high-performance liquid chromatography quadrupole trap tandem mass spectrometry. In this study, hydrochloric acid was used instead of trifluoroacetic acid to hydrolyze polysaccharides, and hydrolysis time was greatly reduced from 5-9 h to 1 h. The 1-phenyl-3-methyl-5-pyrazolone was used for pre-column derivatization of monosaccharides. The parameters of linearity (R2  > 0.999), stability (1.63-2.52%), intra-day and inter-day precision (0.69-0.95%, 1.81-2.77%), repeatability (1.89-2.65%), and recovery (97.63-102.24%) of the method were verified. Satisfactory validation results showed this method could be used to determine the target components. The results indicated the polysaccharide contained glucose, mannose, rhamnose, galactose, ribose, and arabinose. Technique for order preference by similarity to an ideal solution and principal component analysis were used to build an evaluation model based on the monosaccharide composition. The evaluation results showed that the samples from the Qingyang County of Anhui Province were the best when the monosaccharides were used as the evaluation index. Therefore, a new method was established to detect the monosaccharide content of polysaccharides from Polygonatum cyrtonema Hua and comprehensively evaluate the quality of Chinese medicines with polysaccharides as the main active ingredient.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Monosacáridos/análisis , Polygonatum/química , Espectrometría de Masas en Tándem/métodos , Límite de Detección , Modelos Lineales , Reproducibilidad de los Resultados
16.
Phytochem Anal ; 32(5): 785-793, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33480038

RESUMEN

INTRODUCTION: Pre-column derivatisation using 1-phenyl-3-methyl-5-pyrazolone (PMP) is a common method for monosaccharide determination. Herein, a specific ultra-high-performance liquid chromatography quadrupole trap tandem mass spectrometry (UHPLC-QTRAP-MS/MS) method was developed and used for the determination of monosaccharide composition of Lycium barbarum polysaccharide (LBP). OBJECTIVE: Exploration of a new efficient method for monosaccharide determination. METHODS: In our study, hydrochloric acid was used to hydrolyse the polysaccharide obtained from L. barbarum fruits. Principal component analysis (PCA) and technique for order of preference by similarity to ideal solution (TOPSIS) analysis were used for comprehensive evaluation of the samples. The results showed that LBP was composed of seven monosaccharides: galactose, arabinose, mannose, rhamnose, xylose, ribose, and glucose. The linear relationship of the seven monosaccharides was optimum within a certain concentration range. Quantitative recoveries of the seven monosaccharides from the samples ranged from 94.76% to 102.11%. RESULTS: A rapid quantitative detection method was established, in which the hydrolysis time was reduced from 12 h to 2 h. By using LBP as one of the indexes to evaluate the quality of L. barbarum, L. barbarum from Zhongning County, Ningxia Province, was identified as having the best quality among the varieties tested. CONCLUSION: The UHPLC-QTRAP-MS/MS pre-column derivatisation method used in this study was simple, accurate, and sensitive, with good repeatability, and can be used for quality evaluation and origin distinction of L. barbarum and other medicinal plants.


Asunto(s)
Lycium , Monosacáridos , Cromatografía Líquida de Alta Presión , Medicamentos Herbarios Chinos , Frutas , Polisacáridos , Espectrometría de Masas en Tándem
17.
Exp Dermatol ; 29(12): 1186-1190, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32997398

RESUMEN

Psoriasis is a common genetic disease characterized by hyperproliferation and disordered maturation of keratinocytes. To date, many association studies between psoriasis and VDR gene have been conducted, but the results are controversial. Furthermore, vitamin D3 analogue has anti-psoriatic activity; however, the clinical response is variable. This study was conducted to explore whether VDR gene polymorphisms are associated with psoriasis susceptibility and clinical response to calcipotriol in psoriatic patients. A total of 110 patients and 183 controls were genotyped for VDR gene polymorphisms rs2228570, rs731236, rs1544410 and rs7975232 by LDR method. SNP-based and haplotype-based association analyses were subsequently performed. Patients with PASI < 3 were treated with calcipotriol ointment monotherapy. After 6 weeks of therapy, the correlations between efficacy and the genotypes of each polymorphism were evaluated. The results showed that for rs7975232, allele A was significantly over-represented in psoriasis patients relative to controls (39.09% vs. 27.05%, OR (95% CI) = 1.731 (1.213-2.471)), and compared with the reference CC genotype, the following ORs were observed: AA genotype OR = 2.404 (95% CI: 1.085-5.328; P = .034) and GA genotype OR = 2.143 (95% CI: 1.283-3.579; P = .005). Haplotype analyses showed that the rs2228570/rs731236/rs1544410/rs7975232 CTGA was significantly over-represented in psoriasis patients compared with controls (OR (95% CI)=1.907 (1.132-3.214); P = .020). Among the patients with PASI < 3, the response rates to calcipotriol were significantly higher in patients with rs7975232 CC genotypes than in those with other genotypes (x2  = 9.172, P = .010). These data suggest that VDR polymorphisms are associated with psoriasis susceptibility and clinical response to calcipotriol in psoriatic patients.


Asunto(s)
Calcitriol/análogos & derivados , Fármacos Dermatológicos/uso terapéutico , Psoriasis/tratamiento farmacológico , Psoriasis/genética , Receptores de Calcitriol/genética , Adulto , Anciano , Calcitriol/uso terapéutico , Estudios de Casos y Controles , Niño , Femenino , Predisposición Genética a la Enfermedad/genética , Haplotipos , Humanos , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Índice de Severidad de la Enfermedad , Adulto Joven
18.
Zhongguo Zhong Yao Za Zhi ; 45(16): 3890-3899, 2020 Aug.
Artículo en Zh | MEDLINE | ID: mdl-32893586

RESUMEN

By using multivariate statistical analysis to evaluate essential quality, and provide scientific basis for their comprehensive utilization, we established an UHPLC-QTRAP-MS/MS method for the fast, precise, efficient determination of 21 kinds of amino acids and 10 kinds of nucleosides in different species of Dendrobium. The analysis was performed on a Waters XBridge Amide column(2.1 mm×100 mm,3.5 µm) with elution by mobile phase of 0.2% formic acid in water-0.2% formic acid in acetonitrile at a flow rate of 0.2 mL·min~(-1) with the column temperature at 30 ℃. The target compounds were analyzed by the positive ion multiple reaction monitoring(MRM) mode. The comprehensive evaluation of different species of Dendrobium was carried out by PCA and TOPSIS analysis. All 21 kinds of amino acids and 10 nucleosides showed good linearity among certain concentration range(r>0.999), the RSDs of the stability, precision, and repeatability tests were less than 3.0%. The recovery rate was in the range from 93.31% to 107.5%, and RSD was in the range of 1.1%-3.7%. The comprehensive evaluation index obtained with PCA showed that D. huoshanense was significantly higher than others regarding amino acids and D. officinale has higher nucleosides than other species. The biggest C_i difference of TOPSIS was 68.7%, and comprehensive evaluation showed that D. huoshanense produced the highest comprehensive quality. The method is precise, fast and efficient and can provide reliable basis for further researches and intrinsic quality control of Dendrobium.


Asunto(s)
Dendrobium , Espectrometría de Masas en Tándem , Aminoácidos , Cromatografía Líquida de Alta Presión , Nucleósidos
19.
Zhongguo Zhong Yao Za Zhi ; 44(8): 1552-1557, 2019 Apr.
Artículo en Zh | MEDLINE | ID: mdl-31090318

RESUMEN

In order to understand the function of GDP-mannose pyrophosphorylase(GMPP) function and its regulation in polysaccharide biosynthesis mechanism in Dendrobium. D. huoshanense was used to clone GMPP gene. GMPP gene expression in D. huoshanense,D. officinale and D. moniliforme was also determined by qPCR. The results showed that the length of D. huoshanense GMPP gene c DNA sequence is 1 867 bp,containing 1 245 bp open reading frame(ORF),encoding 415 amino acids. Phylogenetic tree analysis showed that D. huoshanense,D. officinale and D. moniliforme are closely related with GMPP taken into consideration. Bioinformatics analysis demonstrated that GMPP sequence similarity among the three species reached as high as 99%. qPCR results indicated that GMPP genes was highly expressed in stem of D. huoshanense compared with its leaf,flower and root. According to GMPP gene expression profile in D. huoshanense,D. officinale and D. moniliforme grown in Huoshan area,it was clear that GMPP in D. huoshanense showed the highest expression level. Furthermore,our findings of GMPP gene expression profile will facilitate future researches into its polysaccharide biosynthetic mechanism.


Asunto(s)
Dendrobium/genética , Nucleotidiltransferasas/genética , Proteínas de Plantas/genética , Secuencia de Bases , Clonación Molecular , Dendrobium/enzimología , Filogenia , Polisacáridos/biosíntesis
20.
Pharm Stat ; 17(5): 458-476, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29726096

RESUMEN

A bioequivalence test is to compare bioavailability parameters, such as the maximum observed concentration (Cmax ) or the area under the concentration-time curve, for a test drug and a reference drug. During the planning of a bioequivalence test, it requires an assumption about the variance of Cmax or area under the concentration-time curve for the estimation of sample size. Since the variance is unknown, current 2-stage designs use variance estimated from stage 1 data to determine the sample size for stage 2. However, the estimation of variance with the stage 1 data is unstable and may result in too large or too small sample size for stage 2. This problem is magnified in bioequivalence tests with a serial sampling schedule, by which only one sample is collected from each individual and thus the correct assumption of variance becomes even more difficult. To solve this problem, we propose 3-stage designs. Our designs increase sample sizes over stages gradually, so that extremely large sample sizes will not happen. With one more stage of data, the power is increased. Moreover, the variance estimated using data from both stages 1 and 2 is more stable than that using data from stage 1 only in a 2-stage design. These features of the proposed designs are demonstrated by simulations. Testing significance levels are adjusted to control the overall type I errors at the same level for all the multistage designs.


Asunto(s)
Ensayos Clínicos como Asunto/métodos , Preparaciones Farmacéuticas/administración & dosificación , Proyectos de Investigación , Disponibilidad Biológica , Simulación por Computador , Humanos , Preparaciones Farmacéuticas/metabolismo , Farmacocinética , Tamaño de la Muestra , Equivalencia Terapéutica
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