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1.
Biotechnol J ; 19(3): e2300502, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38479996

RESUMEN

The anti-inflammatory effect of α-melanocyte-stimulating hormone (α-MSH) in the central nervous system (CNS) has been reported for 40 years. However, the short half-life of α-MSH limits its clinical applications. The previous study has shown that a fusion protein comprising protein transduction domain (PTD), human serum albumin (HSA), and α-MSH extends the half-life of α-MSH, but its anti-inflammatory effect is not satisfactory. In this study, optimization of the structures of fusion proteins was attempted by changing the linker peptide between HSA and α-MSH. The optimization resulted in the improvement of various important characteristics, especially the stability and anti-inflammatory bioactivity, which are important features in protein medicines. Compared to the original linker peptide L0, the 5-amino-acid rigid linker peptide L6 (PAPAP) is the best option for further investigation due to its higher expression (increased by 6.27%), improved purification recovery (increased by 60.8%), excellent thermal stability (Tm = 83.5°C) and better inhibition in NF-κB expression (increased by 81.5%). From this study, the significance of the design of linker peptides in the study of structure-activity relationship of fusion proteins was proved.


Asunto(s)
Albúmina Sérica Humana , alfa-MSH , Humanos , alfa-MSH/farmacología , FN-kappa B/metabolismo , Antiinflamatorios/farmacología
2.
Neuropeptides ; 104: 102410, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38308948

RESUMEN

The immunomodulatory effects of α-melanocyte stimulating hormone (α-MSH) in the central nervous system (CNS) have been investigated for forty years. The clinical applications of α-MSH are limited due to its short half-life. Our previous study has indicated that the short half-life of α-MSH can be extended by fusion with carrier human serum albumin (HSA) and this fusion protein has also retained the anti-inflammatory effect on the CNS. This improvement is still far from the clinical requirements. Thus, we expected to enhance the half-life and activity of the fusion protein by optimizing the linker peptide to get closer to clinical requirements. In a previous study, we screened out two candidates in vitro experiments with a flexible linker peptide (fusion protein with flexible linker peptide, FPFL) and a rigid linker peptide (fusion protein with rigid linker peptide, FPRL), respectively. However, it was not sure whether the anti-inflammatory effects in vitro could be reproduced in vivo. Our results show that FPRL is the best candidate with a longer half-life compared to the traditional flexible linker peptides. Meanwhile, the ability of FPRL to penetrate the blood-brain barrier (BBB) was enhanced, and the inhibition of TNF-α and IL-6 was improved. We also found that the toxicity of FPRL was decreased. All of the results suggested that trying to choose the rigid linker peptide in some fusion proteins may be a potential choice for improving the unsatisfactory characteristics.


Asunto(s)
Albúmina Sérica Humana , alfa-MSH , Animales , Humanos , Ratones , alfa-MSH/farmacología , Antiinflamatorios/farmacología , Barrera Hematoencefálica , Factor de Necrosis Tumoral alfa
3.
ACS Omega ; 8(50): 47530-47539, 2023 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-38144147

RESUMEN

Many low-production and low-efficiency wells in the Zhengzhuang, Fanzhuang, Lu'an, and Yangquan blocks of the Qinshui Basin seriously hinder the development of coalbed methane in China. Through in-depth research on the geological conditions and development technology of coalbed methane, it was found that the main reasons for the existence of a large number of low-production and low-efficiency wells are the fragmentation of coal structure, poor adaptability of vertical well types, sizable well spacing, and mismatched stimulation measures. On this basis, it is proposed to adopt an L-shaped horizontal well and staged Fracking technology in the block with a complete coal structure but low permeability. For stress-concentration areas, the first fracturing of a vertical well has a single crack and a small coverage area; After a period of drainage and production, the use of repeated fracturing technology can increase the complexity of fractures and increase gas production; For the fractured area of coal structure, the use of roof fracturing technology effectively solves the problem of coal fragmentation. In natural fracture development areas, new fractures are formed using fracture turning technology to achieve the effect of increasing production. The above technologies have achieved good results in the Qinshui Basin engineering experiment. Therefore, in-depth research on the geological conditions of coalbed methane and matching related development technologies are the main ways to solve low-efficiency and low-production wells in coalbed methane development blocks.

4.
Bioorg Med Chem ; 83: 117232, 2023 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-36940608

RESUMEN

α-Mangostin (α-MG) has demonstrated to display potent activities against Gram-positive bacterial. However, the contribution of phenolic hydroxyl groups of α-MG to the antibacterial activity remains obscure, severely hampering selection of structure modification to develop more potential α-MG-based anti-bacterial derivatives. Herein, twenty-one α-MG derivatives are designed, synthesized and evaluated for the antibacterial activities. The structure activity relationships (SARs) reveal that the contribution of the phenolic groups ranks as C3 > C6 > C1, and the phenolic hydroxyl group at C3 is essential to the antibacterial activity. Of note, compared to the parent compound α-MG, 10a with one acetyl at C1 exhibits the higher safety profiles due to its higher selectivity and no hemolysis, and the more potent antibacterial efficacy in an animal skin abscess model. Our evidences further present that, in comparison with α-MG, 10a has a stronger ability in depolarizing membrane potentials and leads to more leakage of bacterial proteins, consistent with the results observed by transmission electron microscopy (TEM). Transcriptomics analysis demonstrates those observations possibly relate to disturbed synthesis of proteins participating in the biological process of membrane permeability and integrity. Collectively, our findings provide a valuable insight for developing α-MG-based antibacterial agents with little hemolysis and new action mechanism via structural modifications at C1.


Asunto(s)
Antibacterianos , Xantonas , Animales , Antibacterianos/química , Microscopía Electrónica de Transmisión , Bacterias , Relación Estructura-Actividad , Fenoles , Xantonas/química , Pruebas de Sensibilidad Microbiana
5.
Sensors (Basel) ; 22(24)2022 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-36559951

RESUMEN

Given the continuous improvement in the capabilities of road vehicles to detect obstacles, the road friction coefficient is closely related to vehicular braking control, thus the detection of road surface conditions (RSC), and the level is crucial for driving safety. Non-contact technology for RSC sensing is becoming the main technological and research hotspot for RSC detection because of its fast, non-destructive, efficient, and portable characteristics and attributes. This study started with mapping the relationship between friction coefficients and RSC based on the requirement for autonomous driving. We then compared and analysed the main methods and research application status of non-contact detection schemes. In particular, the use of infrared spectroscopy is expected to be the most approachable technology path to practicality in the field of autonomous driving RSC detection owing to its high accuracy and environmental adaptability properties. We systematically analysed the technical challenges in the practical application of infrared spectroscopy road surface detection, studied the causes, and discussed feasible solutions. Finally, the application prospects and development trends of RSC detection in the fields of automatic driving and exploration robotics are presented and discussed.


Asunto(s)
Accidentes de Tránsito , Conducción de Automóvil , Tecnología , Espectrofotometría Infrarroja , Fricción
6.
BMC Cardiovasc Disord ; 22(1): 465, 2022 11 04.
Artículo en Inglés | MEDLINE | ID: mdl-36333679

RESUMEN

BACKGROUND: Ventilator-associated pneumonia (VAP) is one of the most common intensive care unit (ICU)-acquired infections, which can cause multiple adverse events. Due to bacterial mutation and overuse of antimicrobial drugs, multidrug-resistant organisms (MDRO) has become one of the major causes of postoperative VAP infections in cardiac patients. Therefore, this study aims to explore the risk factors for VAP with MDRO following cardiac surgery in adults. METHODS: The clinical data of adult VAP patients following cardiac surgery in the hospital from Jan 2017 to May 2021 were analyzed retrospectively, and the patients were divided into the MDRO VAP group and the non-MDRO VAP group. Univariable and multivariable logistic regression analyses were performed on risk factors in patients with MDRO VAP. The species and drug sensitivity of pathogens isolated from the VAP patients were also analyzed. RESULTS: A total of 61 VAP cases were involved in this study, with 34 cases in the MDRO VAP group (55.7%) and 27 cases in the non-MDRO VAP group (44.3%). Multivariable logistic regression analysis showed that independent risk factors for MDRO VAP included preoperative creatinine clearance rate (CCR) ≥ 86.6ml, intraoperative cardiopulmonary bypass (CPB) time ≥ 151 min, postoperative acute kidney injury (AKI) and nasal feeding. Gram-negative bacilli were the main pathogens in VAP patients (n = 54, 90.0%), with the highest rate of Acinetobacter baumannii (n = 24, 40.0%). Additionally, patients with MDRO VAP had a significantly longer postoperative intensive care unit (ICU) duration and higher hospitalization costs than non-MDRO VAP patients, but there was no notable difference in the 28-day mortality rate between the two groups. CONCLUSION: Based on implementing measures to prevent VAP, clinicians should pay more attention to patients with kidney disease, longer intraoperative CPB time, and postoperative nasal feeding to avoid MDRO infections.


Asunto(s)
Procedimientos Quirúrgicos Cardíacos , Neumonía Asociada al Ventilador , Adulto , Humanos , Neumonía Asociada al Ventilador/diagnóstico , Neumonía Asociada al Ventilador/epidemiología , Neumonía Asociada al Ventilador/etiología , Estudios Retrospectivos , Unidades de Cuidados Intensivos , Factores de Riesgo , Procedimientos Quirúrgicos Cardíacos/efectos adversos , Antibacterianos/uso terapéutico
7.
Crit Rev Eukaryot Gene Expr ; 32(8): 43-53, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36017915

RESUMEN

Recently, accumulating study shows that some long non-coding RNAs (lncRNAs) have potential protein/peptide-coding capacities. In this study, the coding potential of lncRNA distal-less homeobox 6 antisense 1 (DLX6-AS1) was examined and the roles and downstream pathways of a DLX6-AS1-encoded peptide in non-small-cell lung cancer (NSCLC) cell development were investigated. The peptide-coding potential of lncRNA DLX6-AS1 was extrapolated based on prior ribosome footprint and ribosome sequencing data, IPX0002962000 mass spectrometry dataset, and Getorf bioinformatics analysis. The peptide-coding abilities of several DLX6-AS1 open reading frame (ORF) fragments, as well as protein levels were detected by Western blot assay. Cell proliferative, migratory, and invasive abilities were tested by CCK-8 or Transwell assays, respectively. Potential key biological processes and pathways related to DLX6-AS1 expression were identified by single-gene gene set enrichment analysis (GSEA) based on RNA-seq data of 510 lung adenocarcinoma samples in the TCGA GDC database. The results showed that an ORF of lncRNA DLX6-AS1 could encode a short peptide. The exogenous overexpression of this ORF-encoded peptide promoted NSCLC cell proliferation, migration, and invasion. GSEA analysis suggested that DLX6-AS1 might play crucial roles in cancer progression and wnt signaling pathway. Further analysis revealed that the exogenous overexpression of a DLX6-AS1-encoded peptide could exert its functions by activating the wnt/ß-catenin pathway in NSCLC cells. In conclusion, the exogenous overexpression of a DLX6-AS1-encoded peptide could facilitate NSCLC cell growth by activating wnt/ß-catenin pathway.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , MicroARNs , ARN Largo no Codificante , Carcinoma de Pulmón de Células no Pequeñas/genética , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica/genética , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Humanos , Pulmón , Neoplasias Pulmonares/genética , MicroARNs/genética , Péptidos/genética , Péptidos/metabolismo , ARN Largo no Codificante/genética , Vía de Señalización Wnt/genética , beta Catenina/genética
8.
Front Microbiol ; 13: 877884, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35620098

RESUMEN

Traditional Chinese medicine is one of the ancient medicines which is popular in Asian countries, among which the residue produced by the use of anti-biodegradables is endless, and causes significant adverse impacts on the environment. However, the high acidity of anti-biodegradable residues and some special biological activities make it difficult for microorganisms to survive, resulting in a very low degradation rate of lignocellulose in naturally stacked residues, which directly impedes the degradation of residues. We aimed to identify the fungal strains that efficiently biodegrade anti-biodegradable residue and see the possibility to improve the biodegradation of it and other agricultural wastes by co-cultivating these fungi. We isolated 302 fungal strains from anti-biodegradable residue to test hydrolysis ability. Finally, we found Coniochaeta sp., Fomitopsis sp., Nemania sp., Talaromyces sp., Phaeophlebiopsis sp. which inhabit the anti-biodegradable residues are capable of producing higher concentrations of extracellular enzymes. Synergistic fungal combinations (viz., Fomitopsis sp. + Phaeophlebiopsis sp.; Talaromyces sp. + Coniochaeta sp. + Fomitopsis sp.; Talaromyces sp. + Fomitopsis sp. + Piloderma sp. and Talaromyces sp. + Nemania sp. + Piloderma sp.) have better overall degradation effect on lignocellulose. Therefore, these fungi and their combinations have strong potential to be further developed for bioremediation and biological enzyme industrial production.

9.
Bioorg Chem ; 119: 105515, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34896919

RESUMEN

Natural products are a promising and underappreciated reservoir for the preferred chemical scaffolds in the search of antidiabetic drugs. In this study twenty-one EGC-based derivatives selective to inhibit human pancreatic α-amylase (HPA), the enzyme at the top of the starch digestion pyramid, have been designed and synthesized in terms of the lead myricetin-caffeic acid conjugate 1 reported ever. We focus on methylation of caffeic acid, length of a liker, a double bond contained in the linker on the inhibition activity and selectivity of EGC-based conjugates. As a result, methylation of caffeic acid and the length of a linker affect significantly the activity and selectivity of EGC-based conjugates, but the effect of a double in caffeic acid is limited. Conjugate 2a-1 having a six-carbon-atom linker fused to EGC and caffeic acid demonstrates the most ponent inhibitory activity to HPA and its selectivity towards HPA over α-glucosidase by far superior to that construct 1. Molecular docking studies reveal that conjugate 2a-1 accommodates well to the active site of HPA with four hydrogen bonds in the form of the preorganization of two moieties EGC and caffeic acid via π-stacking interaction. Collectively, conjugating caffeic acid and EGC with an appropriate linker possibly provides a new strategy for finding the specific HPA inhibitors in the discovery of anti-diabetes mellitus drugs.


Asunto(s)
Ácidos Cafeicos/farmacología , Catequina/análogos & derivados , Inhibidores de Glicósido Hidrolasas/farmacología , Hipoglucemiantes/farmacología , alfa-Amilasas/antagonistas & inhibidores , alfa-Glucosidasas/metabolismo , Ácidos Cafeicos/síntesis química , Ácidos Cafeicos/química , Catequina/síntesis química , Catequina/química , Catequina/farmacología , Diabetes Mellitus/tratamiento farmacológico , Diabetes Mellitus/metabolismo , Relación Dosis-Respuesta a Droga , Diseño de Fármacos , Inhibidores de Glicósido Hidrolasas/síntesis química , Inhibidores de Glicósido Hidrolasas/química , Humanos , Hipoglucemiantes/síntesis química , Hipoglucemiantes/química , Simulación del Acoplamiento Molecular , Estructura Molecular , Relación Estructura-Actividad , alfa-Amilasas/metabolismo
10.
Eur J Med Chem ; 226: 113866, 2021 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-34619466

RESUMEN

Eight mono- or disaccharide analogues derived from BLM disaccharide, along with the corresponding carbohydate-dye conjugates have been designed and synthesized in this study, aiming at exploring the effect of a gulose residue on the cellular binding/uptake of BLM disaccharide and it possible uptake mechanism. Our evidence is presented indicating that, for the cellular binding/uptake of BLM disaccharide, a gulose residue is an essential subunit but unrelated to its chemical nature. Interestingly, d-gulose-dye conjugate is able to selectively target A549 cancer cells, but l-gulose-dye conjugate fails. Further uptake mechanism studies demonstrate d-gulose-dye derivatives similar to BLM disaccharide-dye ones behave in a temperature- and ATP-dependent manner, and are partly directed by the GLUT1 receptor. Moreover, d-gulose modifying gemcitabine 53a exhibits more potent antitumor activity compared to derivatives 53b-c in which gemcitabine is decorated with other monosaccharides. Taken together, the monosacharide d-gulose conjugate offers a new strategy for solving cytotoxic drugs via the increased tumor targeting in the therapy of lung cancer.


Asunto(s)
Antineoplásicos/farmacología , Bleomicina/farmacología , Disacáridos/farmacología , Hexosas/farmacología , Células A549 , Antineoplásicos/síntesis química , Antineoplásicos/química , Bleomicina/análogos & derivados , Bleomicina/química , Proliferación Celular/efectos de los fármacos , Disacáridos/síntesis química , Disacáridos/química , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Hexosas/química , Humanos , Estructura Molecular , Relación Estructura-Actividad , Células Tumorales Cultivadas
11.
Biomedicines ; 9(9)2021 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-34572270

RESUMEN

HM-3, an integrin antagonist, exhibits anti-tumor biological responses and therefore has potential as a therapeutic polypeptide. However, the clinical applications of HM-3 are limited by its short half-life. In this study, we genetically fused human serum albumin (HSA) to the N or C-terminus of HM-3 to improve HM-3 pharmacokinetics. HM-3/HSA proteins were successfully expressed in Pichia pastoris and displayed improved pharmacokinetic properties and stability. Among them, the half-life of HM-3-HSA was longer than HSA-HM-3. In vitro, the IC50 values of HSA-HM-3 and HM-3-HSA were 0.38 ± 0.14 µM and 0.25 ± 0.08 µM in B16F10 cells, respectively. In vivo, the inhibition rates of B16F10 tumor growth were 36% (HSA-HM-3) and 56% (HM-3-HSA), respectively, indicating antitumor activity of HM-3-HSA was higher than HSA-HM-3. In conclusion, these results suggested that the HM-3/HSA fusion protein might be potential candidate HM-3 agent for treatment of melanoma and when HSA was fused at the C-terminus of HM-3, the fusion protein had a higher stability and activity.

12.
Eur J Pharm Sci ; 167: 106017, 2021 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-34555448

RESUMEN

HM-3-HSA is an antitumor fusion protein which improved the pharmacokinetics of HM-3. Previous studies reported that HM-3-HSA enhanced antitumor activity of HM-3 in melanoma cells. However, the efficacy and the mechanism of HM-3-HSA in hepatocellular carcinoma, especially its effect on tumor angiogenesis, have not been elucidated. Herein, we showed that HM-3-HSA significantly inhibited the H22 and SMMC-7721 tumor xenografts growth and tumor angiogenesis in vivo, indicating the antitumor activity exerted by HM-3-HSA was closely corrected with its potency on tumor angiogenesis. To investigate the anti-angiogenic mechanism, we evaluated the efficacy of HM-3-HSA in HUVECs in vitro. The results showed that multiple steps of tumor angiogenesis, including endothelial cell proliferation, migration, invasion and tube formation, were substantially inhibited by HM-3-HSA. Mechanism investigations revealed that HM-3-HSA could bind HUVECs via integrin αvß3 and α5ß1 and inhibited phosphorylation of the downstream protein kinases including FAK, Src and PI3 K. Our study was the first to report the activity of HM-3-HSA against hepatocellular carcinoma and tumor angiogenesis as well as the underlying mechanism by which HM-3-HSA to exert its anti-angiogenic activity.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Inhibidores de la Angiogénesis/farmacología , Inhibidores de la Angiogénesis/uso terapéutico , Carcinoma Hepatocelular/tratamiento farmacológico , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Células Endoteliales de la Vena Umbilical Humana , Humanos , Neoplasias Hepáticas/tratamiento farmacológico , Neovascularización Patológica/tratamiento farmacológico , Ensayos Antitumor por Modelo de Xenoinjerto
13.
Bioorg Chem ; 116: 105295, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34455300

RESUMEN

We previously discovered extrahepatic cytochrome P450 1B1 (CYP1B1) degraders able to overcome drug resistance toward docetaxel using a PROTACs technology, however, the underexplored structure activity relationships and poor water solubility posed a major hurdle in the development of CYP1B1 degraders. Herein, continuous efforts are made to develop more promising α-naphthoflavone (ANF)-derived chimeras for degrading CYP1B1. Guided by the strongest ANF-derived CYP1B1 degrader 3a we ever reported, 17 ANF analogues are designed and synthesized to evaluate the CYP1B1 degradation and resultant resistance reversal. In degrading CYP1B1 and sensitizing drug resistance, 4d with a 1, 5-cis triazole coupling mode at (C3') of B ring of ANF exhibited the similar potency as 3a carrying a 1, 4-trans triazole fragment at (C4') of B ring, but more obvious selectivity of 4d toward CYP1B1 over CYP1A2 is observed. When an oxygen was inserted into the linker of 4d, 4f demonstrated better water solubility, a more potent ability in degrading CYP1B1 and reversing drug resistance, and a promising selectivity. Collectively, a substitution position, an alkyne-azide cyclization and a liker type significantly affect the ability of ANF-thalidomide conjugates in eliminating drug resistance of CYP1B1-expressing DU145 (DU145/CY) cells to docetaxel via targeted CYP1B1 degradation.


Asunto(s)
Antineoplásicos/farmacología , Benzoflavonas/farmacología , Citocromo P-450 CYP1B1/antagonistas & inhibidores , Resistencia a Antineoplásicos/efectos de los fármacos , Neoplasias de la Próstata/tratamiento farmacológico , Antineoplásicos/síntesis química , Antineoplásicos/química , Benzoflavonas/síntesis química , Benzoflavonas/química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Citocromo P-450 CYP1B1/metabolismo , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Masculino , Estructura Molecular , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Solubilidad , Relación Estructura-Actividad
14.
Materials (Basel) ; 14(13)2021 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-34206300

RESUMEN

Spectrometers based on acousto-optic tunable filters (AOTFs) have several advantages, such as stable temperature adaptability, no moving parts, and wavelength selection through electrical modulation, compared with the traditional grating and Fourier transform spectrometers. Therefore, AOTF spectrometers can realize stable in situ measurement on the lunar surface under wide temperature ranges and low light environments. AOTF imaging spectrometers were first employed for in situ measurement of the lunar surface in the Chinese Chang'e project. The visible and near-infrared imaging spectrometer and the lunar mineralogical spectrometer have been successfully deployed on board the Chang'e-3/4 and Chang'e-5 missions. In this review, we investigate the performance indicators, structural design, selected AOTF performance parameters, data acquisition of the three lunar in situ spectral instruments used in the Chang'e missions. In addition, we also show the scientific achievement of lunar technology based on in situ spectral data.

15.
Sci Rep ; 11(1): 11547, 2021 06 02.
Artículo en Inglés | MEDLINE | ID: mdl-34078986

RESUMEN

Automated construction of location graphs is instrumental but challenging, particularly in logistics optimisation problems and agent-based movement simulations. Hence, we propose an algorithm for automated construction of location graphs, in which vertices correspond to geographic locations of interest and edges to direct travelling routes between them. Our approach involves two steps. In the first step, we use a routing service to compute distances between all pairs of L locations, resulting in a complete graph. In the second step, we prune this graph by removing edges corresponding to indirect routes, identified using the triangle inequality. The computational complexity of this second step is [Formula: see text], which enables the computation of location graphs for all towns and cities on the road network of an entire continent. To illustrate the utility of our algorithm in an application, we constructed location graphs for four regions of different size and road infrastructures and compared them to manually created ground truths. Our algorithm simultaneously achieved precision and recall values around 0.9 for a wide range of the single hyperparameter, suggesting that it is a valid approach to create large location graphs for which a manual creation is infeasible.

16.
Eur J Med Chem ; 220: 113487, 2021 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-33933752

RESUMEN

Clinically, chemotherapy is the mainstay in the treatment of multiple cancers. However, highly adaptable and activated survival signaling pathways of cancer cells readily emerge after long exposure to chemotherapeutics drugs, resulting in multi-drug resistance (MDR) and treatment failure. Recently, growing evidences indicate that the molecular action mechanisms of cancer MDR are closely associated with abnormalities in saccharides. In this review, saccharides affecting cancer MDR development are elaborated and analyzed in terms of aberrant aerobic glycolysis and its related enzymes, abnormal glycan structures and their associated enzymes, and glycoproteins. The reversal strategies including depletion of ATP, circumventing the original MDR pathway, activation by or inhibition of sugar-related enzymes, combination therapy with traditional cytotoxic agents, and direct modification on the sugar moiety, are ultimately proposed. It follows that abnormal saccharides have a significant effect on cancer MDR development, providing a new perspective for overcoming MDR and improving the outcome of chemotherapy.


Asunto(s)
Antineoplásicos/farmacología , Resistencia a Múltiples Medicamentos/efectos de los fármacos , Resistencia a Antineoplásicos/efectos de los fármacos , Neoplasias/tratamiento farmacológico , Polisacáridos/farmacología , Antineoplásicos/química , Humanos , Estructura Molecular , Neoplasias/metabolismo , Polisacáridos/química
17.
J Ethnopharmacol ; 268: 113640, 2021 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-33307058

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Terminalia chebula Retz. (T.chebula) is an important medicinal plant in Tibetan medicine and Ayurveda. T.chebula is known as the "King of Tibetan Medicine", due to its widespread clinical pharmacological activity such as anti-inflammatory, antioxidative, antidiabetic as well as anticancer in lots of in vivo and in vitro models. In this study, we use transgenic and/or RNAi Caenorhabditis elegans (C.elegans) model to simulation the AD pathological features induced by Aß, to detect the effect of TWE on improving Aß-induced toxicity and the corresponding molecular mechanism. AIM OF STUDY: The study aimed to tested the activities and its possible mechanism of T.chebula to against Aß1-42 induced toxicity and Aß1-42 aggregation. MATERIALS AND METHODS: Using transgenic C.elegans strain CL2006 and CL4176 as models respond to paralytic induced by Aß toxicity. The transcription factors DAF-16 and SKN-1 were analyzed used a fluorescence microscope in transgenic strains (DAF-16:GFP, SKN-1:GFP). The function of DAF-16 and SKN-1 was further investigated using loss-of-function strains by feeding RNA interference (RNAi) bacteria. To evaluate the aggregation level of Aß in the transgenic C.elegans, Thioflavin S (ThS) staining and WB visualized the levels of Aß monomers and oligomers. RESULTS: TWE treatment can significantly improve the paralysis of transgenic C.elegans caused by Aß aggregation (up to 14%). The Aß aggregates in transgenic C.elegans are significantly inhibited under TWE exposure (up to 70%). TWE increases the nuclear localization of the key transcription factor DAF-16 and HSF-1, which in turn leads to the expression of downstream Hsp-16.2 protein and exerts its inhibitory effect on Aß aggregation. Meanwhile, paralysis improved has not observed in SKN-1 mutation and/or RNAi C.elegans. CONCLUSION: Our results indicate that TWE can protect C.elegans against the Aß1-42-induced toxicity, inhibition Aß1-42 aggregation and delaying Aß-induced paralysis. The neuroprotective effect of TWE involves the activation of DAF-16/HSF-1/Hsp-16.2 pathway.


Asunto(s)
Péptidos beta-Amiloides/toxicidad , Fragmentos de Péptidos/toxicidad , Extractos Vegetales/uso terapéutico , Agregación Patológica de Proteínas/inducido químicamente , Agregación Patológica de Proteínas/prevención & control , Terminalia , Péptidos beta-Amiloides/antagonistas & inhibidores , Animales , Animales Modificados Genéticamente , Caenorhabditis elegans , Relación Dosis-Respuesta a Droga , Humanos , Fragmentos de Péptidos/antagonistas & inhibidores , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacología , Agregación Patológica de Proteínas/patología
18.
Curr Microbiol ; 77(8): 1924-1931, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32306114

RESUMEN

Strain 16W4-4-3 T was isolated from the oil-well production water in Qinghai Oilfield, China. Cells were Gram-stain-negative, rod-shaped, catalase- and oxidase-positive, facultatively anaerobic and motile by single polar flagellum. The 16S rRNA gene sequences of strain 16W4-4-3 T showed the highest similarities with Pseudomonas profundi M5T (98.8%), P. pelagia CL-AP6T (98.0%), P. salina XCD-X85T (97.7%), and P. sabulinigri J64T (97.5%). The phylogenetic trees based on multilocus sequence analyses with concatenating 16S rRNA, gyrB, rpoD and rpoB genes suggested that this strain should be affiliated to the genus Pseudomonas but remotely related from other species. In addition, whole genome analyses revealed that the digital DNA-DNA hybridization values and average nucleotide identities of strain 16W4-4-3 T against its close relatives were all below 28.8% and 86.5%, respectively. Furthermore, the isolate had totally different whole cell protein profile as compared to those of other species. Major fatty acids were summed feature 8 (C18:1ω7c and/or C18:1ω6c), C16:0, summed feature 3 (C16:1ω7c and/or C16:1ω6c) and C17:0cyclo. Major isoprenoid quinone was ubiquinone (Q-9), and major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, and phosphatidylethanolamine. The DNA G + C content was 58.5 mol%. Therefore, phenotypic, phylogenetic, genomic, chemotaxonomic, and proteomic traits showed that the isolate represented a novel species of the genus Pseudomonas, the name Pseudomonas saliphila sp. nov. is proposed. Type strain is 16W4-4-3 T (= CGMCC 1.13350 T = KCTC 72619 T).


Asunto(s)
Yacimiento de Petróleo y Gas/microbiología , Filogenia , Pseudomonas/clasificación , Microbiología del Agua , Técnicas de Tipificación Bacteriana , Composición de Base , China , ADN Bacteriano/genética , Ácidos Grasos/química , Genes Bacterianos , Tipificación de Secuencias Multilocus , Hibridación de Ácido Nucleico , Fosfolípidos/química , Pseudomonas/aislamiento & purificación , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Ubiquinona/química
19.
Int J Syst Evol Microbiol ; 70(3): 1571-1577, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32228746

RESUMEN

The present study aimed to determine the taxonomic positions of strains designated R-5-52-3T, R-5-33-5-1-2, R-5-48-2 and R-5-51-4 isolated from hot spring water samples. Cells of these strains were Gram-stain-negative, non-motile and rod-shaped. The strains shared highest 16S rRNA gene sequence similarity with Vulcaniibacterium thermophilum KCTC 32020T (95.1%). Growth occurred at 28-55 °C, at pH 6-8 and with up to 3 % (w/v) NaCl. DNA fingerprinting, biochemical, phylogenetic and 16S rRNA gene sequence analyses suggested that R-5-52-3T, R-5-33-5-1-2, R-5-48-2 and R-5-51-4 were different strains but belonged to the same species. Hence, R-5-52-3T was chosen for further analysis and R-5-33-5-1-2, R-5-48-2 and R-5-51-4 were considered as additional strains of this species. R-5-52-3T possessed Q-8 as the only quinone and iso-C15:0, iso-C11:0, C16 : 0 and iso-C17 : 0 as major fatty acids. The polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, unidentified polar lipids and two unidentified phospholipids. The genomic G+C content was 71.6 mol%. Heat shock proteins (e.g. Hsp20, GroEL, DnaK and Clp ATPases) were noted in the R-5-52-3T genome, which could suggest its protection in the hot spring environment. Pan-genome analysis showed the number of singleton gene clusters among Vulcaniibacterium members varied. Average nucleotide identity (ANI) values between R-5-52-3T, Vulcaniibacterium tengchongense YIM 77520T and V. thermophilum KCTC 32020T were 80.1-85.8 %, which were below the cut-off level (95-96 %) recommended as the ANI criterion for interspecies identity. Thus, based on the above results, strain R-5-52-3T represents a novel species of the genus Vulcaniibacterium, for which the name Vulcaniibacterium gelatinicum sp. nov. is proposed. The type strain is R-5-52-3T (=KCTC 72061T=CGMCC 1.16678T).


Asunto(s)
Manantiales de Aguas Termales/microbiología , Filogenia , Xanthomonadaceae/clasificación , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/química , Genes Bacterianos , Fosfolípidos/química , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Ubiquinona/química , Microbiología del Agua , Xanthomonadaceae/aislamiento & purificación
20.
Eur J Med Chem ; 193: 112221, 2020 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-32222663

RESUMEN

Heparanase (HPSE)-directed tumor progression plays a crucial role in mediating tumor-host crosstalk and priming the tumor microenvironment, leading to tumor growth, metastasis and chemo-resistance. HPSE-mediated breakdown of structural heparan sulfate (HS) networks in the extracellular matrix (ECM) and basement membranes (BM) directly facilitates tumor growth and metastasis. Lysosome HPSE also induces multi-drug resistance via enhanced autophagy. Therefore, HPSE inhibitors development has become an attractive topic to block tumor growth and metastasis or eliminate drug resistance. In this review, we summarize HPSE inhibitors applied experimentally and clinically according to interaction with the binding sites of HPSE and participation of growth factors. The antitumor activity and structure-activity relationship (SAR) are also emphasized.


Asunto(s)
Antineoplásicos/farmacología , Inhibidores Enzimáticos/farmacología , Glucuronidasa/antagonistas & inhibidores , Neoplasias/tratamiento farmacológico , Animales , Antineoplásicos/química , Productos Biológicos/química , Productos Biológicos/farmacología , Ensayos de Selección de Medicamentos Antitumorales , Inhibidores Enzimáticos/química , Glucuronidasa/metabolismo , Humanos , Neoplasias/metabolismo , Oligosacáridos/química , Oligosacáridos/farmacología , Bibliotecas de Moléculas Pequeñas/química , Bibliotecas de Moléculas Pequeñas/farmacología
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