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1.
BMC Plant Biol ; 24(1): 343, 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38671396

RESUMEN

BACKGROUND: Drought stress severely impedes plant growth, and only a limited number of species exhibit long-term resistance to such conditions. Pinus sylvestris var. mongolica, a dominant tree species in arid and semi-arid regions of China, exhibits strong drought resistance and plays a crucial role in the local ecosystem. However, the molecular mechanisms underlying this resistance remain poorly understood. RESULTS: Here, we conducted transcriptome sequence and physiological indicators analysis of needle samples during drought treatment and rehydration stages. De-novo assembly yielded approximately 114,152 unigenes with an N50 length of 1,363 bp. We identified 6,506 differentially expressed genes (DEGs), with the majority being concentrated in the heavy drought stage (4,529 DEGs). Functional annotation revealed enrichment of drought-related GO terms such as response to water (GO:0009415: enriched 108 genes) and response to water deprivation (GO:0009414: enriched 106 genes), as well as KEGG categories including MAPK signaling pathway (K04733: enriched 35 genes) and monoterpenoid biosynthesis (K21374: enriched 27 genes). Multiple transcription factor families and functional protein families were differentially expressed during drought treatment. Co-expression network analysis identified a potential drought regulatory network between cytochrome P450 genes (Unigene4122_c1_g1) and a core regulatory transcription factor Unigene9098_c3_g1 (PsNAC1) with highly significant expression differences. We validated PsNAC1 overexpression in Arabidopsis and demonstrated enhanced drought resistance. CONCLUSIONS: These findings provide insight into the molecular basis of drought resistance in P. sylvestris var. mongolica and lay the foundation for further exploration of its regulatory network.


Asunto(s)
Sequías , Pinus sylvestris , Proteínas de Plantas , Transcriptoma , Pinus sylvestris/genética , Pinus sylvestris/fisiología , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estrés Fisiológico/genética , Regulación de la Expresión Génica de las Plantas , Perfilación de la Expresión Génica , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Genes de Plantas
2.
Pediatr Nephrol ; 39(8): 2377-2391, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38589698

RESUMEN

BACKGROUND: Lowe syndrome is characterized by the presence of congenital cataracts, psychomotor retardation, and dysfunctional proximal renal tubules. This study presents a case of an atypical phenotype, investigates the genetic characteristics of eight children diagnosed with Lowe syndrome in southern China, and performs functional analysis of the novel variants. METHODS: Whole-exome sequencing was conducted on eight individuals diagnosed with Lowe syndrome from three medical institutions in southern China. Retrospective collection and analysis of clinical and genetic data were performed, and functional analysis was conducted on the five novel variants. RESULTS: In our cohort, the clinical symptoms of the eight Lowe syndrome individuals varied. One patient was diagnosed with Lowe syndrome but did not present with congenital cataracts. Common features among all patients included cognitive impairment, short stature, and low molecular weight proteinuria. Eight variations in the OCRL gene were identified, encompassing three previously reported and five novel variations. Among the novel variations, three nonsense mutations were determined to be pathogenic, and two patients harboring novel missense variations of uncertain significance exhibited severe typical phenotypes. Furthermore, all novel variants were associated with altered protein expression levels and impacted primary cilia formation. CONCLUSION: This study describes the first case of an atypical Lowe syndrome patient without congenital cataracts in China and performs a functional analysis of novel variants in the OCRL gene, thereby expanding the understanding of the clinical manifestations and genetic diversity associated with Lowe syndrome.


Asunto(s)
Síndrome Oculocerebrorrenal , Fenotipo , Monoéster Fosfórico Hidrolasas , Humanos , Síndrome Oculocerebrorrenal/genética , Síndrome Oculocerebrorrenal/diagnóstico , Masculino , Femenino , Niño , Monoéster Fosfórico Hidrolasas/genética , China , Preescolar , Estudios Retrospectivos , Secuenciación del Exoma , Lactante , Adolescente , Mutación , Pueblo Asiatico/genética , Codón sin Sentido , Pueblos del Este de Asia
3.
Molecules ; 29(13)2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38999181

RESUMEN

Aqueous zinc-ion batteries (ZIBs) are widely recognized as highly promising energy storage devices because of their inherent characteristics, including superior safety, affordability, eco-friendliness, and various other benefits. However, the significant corrosion of the zinc metal anode, side reactions occurring between the anode and electrolyte, and the formation of zinc dendrites significantly hinder the practical utilization of ZIBs. Herein, we utilized an electrodeposition method to apply a unique hydrous molybdenum oxide (HMoOx) layer onto the surface of the zinc metal anode, aiming to mitigate its corrosion and side reactions during the process of zinc deposition and stripping. In addition, the HMoOx layer not only improved the hydrophilicity of the zinc anode, but also adjusted the migration of Zn2+, thus facilitating the uniform deposition of Zn2+ to reduce dendrite formation. A symmetrical cell with the HMoOx-Zn anode displayed reduced-voltage hysteresis (80 mV at 2.5 mA/cm2) and outstanding cycle stability after 3000 cycles, surpassing the performance of the uncoated Zn anode. Moreover, the HMoOx-Zn anode coupled with a γ-MnO2 cathode created a considerably more stable rechargeable full battery compared to the bare Zn anode. The HMoOx-Zn||γ-MnO2 full cell also displayed excellent cycling stability with a charge/discharge-specific capacity of 129/133 mAh g-1 after 300 cycles. In summary, this research offers a straightforward and advantageous approach that can significantly contribute to the future advancements in rechargeable ZIBs.

4.
BMC Neurosci ; 23(1): 77, 2022 12 16.
Artículo en Inglés | MEDLINE | ID: mdl-36527006

RESUMEN

BACKGROUND: Succinic semialdehyde dehydrogenase deficiency (SSADH-D) is an autosomal recessive gamma-aminobutyric acid (GABA) metabolism disorder that can arise due to ALDH5A1 mutations, resulting in severe, progressive, untreatable neurodegeneration. SSADH-D is primarily studied using simplified models, such as HEK293 cells overexpressing genes of interest, but such overexpression can result in protein aggregation or pathway saturation that may not be representative of actual underlying disease phenotypes. METHODS: We used a CRISPR/Cas9 approach to generate human iPSC cell lines bearing ALDH5A1 mutations. Through screening, two different mutant cell lines, NM_001080.3: c.727_735del (p.L243_S245del) and NM_001080.3: c.730_738del (p.A244_Q246del), were obtained. We induced iPSCs to neural stem cells and analyzed the characteristics of ALDH5A1 mutations in stem cells. RESULTS: The human iPSC and NSC cell lines presented typical stem cell-like morphology. We found changes in ALDH5A1 expression and GABA accumulation in the different cell lines. In addition, by analyzing the cDNA between the wild-type and the mutant cell lines, we found that the mutant cell lines had a splicing variant. CONCLUSIONS: iPSCs represent a promising in vitro model for SSADH-D that can be used to study early central nervous system developmental alterations and pathogenic mechanisms.


Asunto(s)
Células Madre Pluripotentes Inducidas , Células-Madre Neurales , Humanos , Niño , Células HEK293 , Succionato-Semialdehído Deshidrogenasa/genética , Succionato-Semialdehído Deshidrogenasa/metabolismo , Discapacidades del Desarrollo/diagnóstico , Discapacidades del Desarrollo/genética , Discapacidades del Desarrollo/patología , Mutación , Ácido gamma-Aminobutírico/metabolismo , Células-Madre Neurales/metabolismo
5.
Soft Matter ; 18(47): 8920-8930, 2022 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-36440607

RESUMEN

The increasing importance of surfactants in various fields has led to growing interest in the comprehensive characterization of surfactants. The critical micelle concentration (CMC), the most fundamental property of surfactants, is a parameter that must be measured. In particular, with the continuous expansion of the molecular structure of surfactants, numerous novel amphiphilic molecules have been developed that are capable of forming ordered aggregates in various solvent systems. Fluorescence spectroscopy, based on the differences in fluorescence intensity and wavelength of the fluorescent probe in the solvent phase and micellar phase, can sensitively detect the CMC of surfactants. This review aims to summarize the various fluorescence methods used to determine the CMC, including aggregation-induced emission (AIE), excimer formation, intramolecular charge transfer (ICT), and other miscellaneous strategies. The difficulties and limitations in the CMC determination process are also described. Further suggestions are provided to guide the existing fluorescence probes and the corresponding fluorescence methods to detect critical aggregation concentrations of amphiphilic molecules.


Asunto(s)
Micelas , Tensoactivos
6.
Int J Mol Sci ; 22(13)2021 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-34281238

RESUMEN

This study evaluated the effects of different light spectra (white light; WL, blue light; BL and red light; RL) on the root morphological traits and metabolites accumulation and biosynthesis in Sarcandra glabra. We performed transcriptomic and metabolomic profiling by RNA-seq and ultra-performance liquid chromatography-electrospray ionization-tandem mass spectrometry (UPLC-ESI-MS/MS), respectively. When morphological features were compared to WL, BL substantially increased under-ground fresh weight, root length, root surface area, and root volume, while RL inhibited these indices. A total of 433 metabolites were identified, of which 40, 18, and 68 compounds differentially accumulated in roots under WL (WG) vs. roots under BL (BG), WG vs. roots under RL (RG), and RG vs. BG, respectively. In addition, the contents of sinapyl alcohol, sinapic acid, fraxetin, and 6-methylcoumarin decreased significantly in BG and RG. In contrast, chlorogenic acid, rosmarinyl glucoside, quercitrin and quercetin were increased considerably in BG. Furthermore, the contents of eight terpenoids compounds significantly reduced in BG. Following transcriptomic profiling, several key genes related to biosynthesis of phenylpropanoid-derived and terpenoids metabolites were differentially expressed, such as caffeic acid 3-O-methyltransferase) (COMT), hydroxycinnamoyl-CoA shikimate hydroxycinnamoyl transferase (HCT), O-methyltransferase (OMT), and 1-deoxy-D-xylulose-5-phosphate synthetase (DXS). In summary, our findings showed that BL was suitable for growth and accumulation of bioactive metabolites in root tissue of S. glabra. Exposure to a higher ratio of BL might have the potential to improve the production and quality of S. glabra seedlings, but this needs to be confirmed further.


Asunto(s)
Color , Magnoliopsida/efectos de la radiación , Raíces de Plantas/efectos de la radiación , Metabolismo Secundario/efectos de la radiación , Plantones/efectos de la radiación , Magnoliopsida/crecimiento & desarrollo , Magnoliopsida/metabolismo , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/metabolismo , Plantones/crecimiento & desarrollo , Plantones/metabolismo , Terpenos/metabolismo
7.
BMC Plant Biol ; 20(1): 476, 2020 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-33076818

RESUMEN

BACKGROUND: Sarcandra glabra is an evergreen and traditional Chinese herb with anti-oxidant, anti-bacterial, anti-inflammatory, and anti-tumor effects. Light is one of the most influential factor affecting the growth and quality of herbs. In recent times, the introduction of Light Emission Diode (LED) technology has been widely used for plants in greenhouse. However, the impact of such lights on plant growth and the regulatory mechanism of phenylpropanoid-derived compounds in S. glabra remain unclear. RESULTS: The red LED light (RL) substantially increased the plant height and decreased the stem diameter and leaf area relative to the white LED light (WL), while the blue LED light (BL) significantly reduced the height and leaf area of S. glabra. According to transcriptomic profiling, 861, 378, 47, 10,033, 7917, and 6379 differentially expressed genes (DEGs) were identified among the groups of leaf tissue under BL (BY) vs. leaf tissue under RL (RY), BY vs. leaf tissue under WL (WY), RY vs. WY, root tissue under WL (WG) vs. WY, stem tissue under WL (WJ) vs. WG, and WJ vs. WY, respectively. We identified 46 genes encoding for almost all known enzymes involved in phenylpropanoid biosynthesis, e.g., phenylalanine ammonia lyase (PAL), chalcone synthase (CHS), and flavonol synthase (FLS). We found 53 genes encoding R2R3-MYB proteins and bHLH proteins, respectively, where several were related to flavonoids biosynthesis. A total of 454 metabolites were identified based on metabolomic profiling, of which 44, 87, and 296 compounds were differentially produced in WY vs. RY, WY vs. BY, and WY vs. WG. In BY there was a substantial reduction in the production of esculetin, caffeic acid, isofraxidin, and fraxidin, while the yields of quercitrin and kaempferol were significantly up-regulated. In RY, the contents of cryptochlorogenic acid, cinnamic acid, and kaempferol decreased significantly. Besides, in WG, the production of metabolites (e.g. chlorogenic acid, cryptochlorogenic acid, and scopolin) declined, while their yields increased significantly (e.g. esculetin, fraxetin, isofraxidin, and fraxidin). CONCLUSION: These results provide further insight into the regulatory mechanism of accumulation patterns of phenylpropanoid-derived compounds in S. glabra under various light conditions, allowing optimum breeding conditions to be developed for this plant.


Asunto(s)
Magnoliopsida/metabolismo , Plantones/metabolismo , Medicamentos Herbarios Chinos , Genes de Plantas , Luz , Magnoliopsida/anatomía & histología , Magnoliopsida/crecimiento & desarrollo , Magnoliopsida/efectos de la radiación , Metabolómica , Filogenia , Proteínas de Plantas/metabolismo , Plantones/anatomía & histología , Plantones/crecimiento & desarrollo , Plantones/efectos de la radiación , Factores de Transcripción/metabolismo , Transcriptoma
8.
J Antimicrob Chemother ; 75(7): 1850-1858, 2020 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-32154866

RESUMEN

OBJECTIVES: To evaluate in vitro activity of the novel ß-lactamase boronate inhibitor taniborbactam (VNRX-5133) combined with cefepime or meropenem against 500 urinary Gram-negative bacilli. METHODS: Cefepime/taniborbactam and 14 comparators were tested by broth microdilution or agar dilution methods. A total of 450 Enterobacteriaceae and 50 Pseudomonas aeruginosa were selected from 2017 to 2019 based on different ß-lactamase-producing or resistance phenotypes. For carbapenem-non-susceptible isolates, the modified carbapenem inactivation method (mCIM), EDTA-CIM (eCIM) and amplification of carbapenemase genes were performed. For NDM-producing isolates and those with cefepime/taniborbactam MICs >8 mg/L, the MICs of meropenem/taniborbactam and/or mutations in PBP3 were investigated. RESULTS: Taniborbactam improved cefepime activity with the same efficiency as avibactam improved ceftazidime activity against 66 KPC-2 producers, 30 non-carbapenemase-producing carbapenem-non-susceptible Enterobacteriaceae and 28 meropenem-susceptible P. aeruginosa. However, cefepime/taniborbactam exhibited more potent activity than ceftazidime/avibactam against 56 ESBL-producing, 61 AmpC-producing, 32 ESBL and AmpC co-producing, 87 NDM-producing and 21 MBL-producing Enterobacteriaceae predicted by phenotypic mCIM and eCIM, 82 Enterobacteriaceae that were susceptible to all tested ß-lactams and 22 carbapenem-non-susceptible P. aeruginosa. A four-amino acid 'INYR' or 'YRIN' insertion, with or without a one/two-amino acid mutation in PBP3, may have caused cefepime/taniborbactam MICs >8 mg/L among 96.6% (28/29) of the NDM-5-producing Escherichia coli, which accounted for the majority of isolates with cefepime/taniborbactam MICs >8 mg/L (76.1%, 35/46). CONCLUSIONS: Taniborbactam's superior breadth of activity, when paired with cefepime or meropenem, suggests these ß-lactam/ß-lactamase inhibitor combinations could be promising candidates for treating urinary tract infections caused by ESBL and/or AmpC, KPC or NDM-producing Enterobacteriaceae or P. aeruginosa.


Asunto(s)
Antibacterianos , Inhibidores de beta-Lactamasas , Antibacterianos/farmacología , Compuestos de Azabiciclo/farmacología , Ácidos Borínicos , Ácidos Carboxílicos , Cefepima , Ceftazidima , China , Combinación de Medicamentos , Meropenem/farmacología , Pruebas de Sensibilidad Microbiana , Inhibidores de beta-Lactamasas/farmacología , beta-Lactamasas/genética
9.
J Clin Lab Anal ; 34(2): e23073, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31628681

RESUMEN

OBJECTIVE: To detect the levels of signal transducer and activator of transcription 4 (STAT4) and soluble endoglin (sEng) in preeclampsia patients and analyze the diagnostic values of STAT4 and sEng in preeclampsia. METHODS: Fifty-four pregnant women with preeclampsia from October 2017 to June 2018 were included in this study. Twenty-eight matched healthy pregnant women were set as the control group. The general clinical characteristics were measured. Serum STAT4 and sEng were detected by ELISA. Correlation between STAT4 and sEng, and their diagnostic value in preeclampsia were analyzed. RESULTS: Compared with control, the prothrombin time in preeclampsia was significantly lower, while the mean arterial pressure, 24-hour urine protein, serum creatinine, fibrinogen, and ALT were significantly higher. The circulating levels of STAT4 and sEng were significantly increased in the preeclampsia. The serum levels of STAT4 and sEng in preeclampsia were positively correlated. For the diagnosis of preeclampsia by the serum STAT4, AUC is 0.902, and the sensitivity and specificity are 0.893 and 0.929. By the serum sEng, AUC is 0.873, and the sensitivity and specificity are 0.816 and 0.905. CONCLUSION: The serum levels of STAT4 and sEng were significantly increased in preeclampsia with disease severity status, which have promise as diagnostic markers in preeclampsia.


Asunto(s)
Endoglina/sangre , Preeclampsia/sangre , Preeclampsia/diagnóstico , Factor de Transcripción STAT4/sangre , Adulto , Biomarcadores/sangre , Estudios de Casos y Controles , Femenino , Humanos , Embarazo
10.
Nonlinear Dyn ; 101(3): 1933-1949, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32836821

RESUMEN

Since the outbreak of coronavirus disease in 2019 (COVID-19), the disease has rapidly spread to the world, and the cumulative number of cases is now more than 2.3 million. We aim to study the spread mechanism of rumors on social network platform during the spread of COVID-19 and consider education as a control measure of the spread of rumors. Firstly, a novel epidemic-like model is established to characterize the spread of rumor, which depends on the nonautonomous partial differential equation. Furthermore, the registration time of network users is abstracted as 'age,' and the spreading principle of rumors is described from two dimensions of age and time. Specifically, the susceptible users are divided into higher-educators class and lower-educators class, in which the higher-educators class will be immune to rumors with a higher probability and the lower-educators class is more likely to accept and spread the rumors. Secondly, the existence and uniqueness of the solution is discussed and the stability of steady-state solution of the model is obtained. Additionally, an interesting conclusion is that the education level of the crowd is an essential factor affecting the final scale of the spread of rumors. Finally, some control strategies are presented to effectively restrain the rumor propagation, and numerical simulations are carried out to verify the main theoretical results.

11.
J Cell Biochem ; 120(9): 15776-15789, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31074048

RESUMEN

Traumatic brain injury (TBI) is a serious public health problem as well as a leading cause of severe posttraumatic disability. Numerous studies indicate that the differentially expressed genes (DEGs) of neural signaling pathways are strongly correlated with brain injury. To further analyze the roles of the DGEs in the central nervous system, here we systematically investigated TBI on the hippocampus and its injury mechanism at the whole genome level. On the basis of Gene Ontology and Kyoto Encyclopedia of Genes and Genomes Analyses, we revealed that the DEGs were involved in many signaling pathways related to the nervous system, especially neuronal survival-related pathways. Finally, we verified the microarray results and detected the gene expression of neuronal survival-related genes in the hippocampus by using real-time quantitative polymerase chain reaction. With Western blot and axon growth assay, the expression of P2rx3 was upregulated in rats subjected to TBI, and overexpression of P2rx3 promoted neurite growth of NG108 cells. Our results suggested that the DEGs (especially P2rx3) and several signaling pathways might play a pivotal role in TBI. We also provided several targeted genes related to TBI for future investigation.


Asunto(s)
Lesiones Traumáticas del Encéfalo/genética , Perfilación de la Expresión Génica/métodos , Receptores Purinérgicos P2X3/genética , Receptores Purinérgicos P2X3/metabolismo , Animales , Lesiones Traumáticas del Encéfalo/metabolismo , Línea Celular , Modelos Animales de Enfermedad , Regulación de la Expresión Génica , Redes Reguladoras de Genes , Masculino , Análisis de Secuencia por Matrices de Oligonucleótidos , Ratas , Ratas Sprague-Dawley , Regulación hacia Arriba
12.
J Am Chem Soc ; 141(42): 16781-16789, 2019 10 23.
Artículo en Inglés | MEDLINE | ID: mdl-31553608

RESUMEN

Bacterial infectious diseases, especially those caused by Gram-positive bacteria, have been seriously threatening human health. Preparation of a multifunctional system bearing both rapid bacterial differentiation and effective antibacterial effects is highly in demand, but remains a severe challenge. Herein, we rationally designed and successfully developed a sequence of aggregation-induced emission luminogens (AIEgens) with orderly enhanced D-A strength. Evaluation of structure-function relationships reveals that AIEgens having intrinsic positive charge and proper ClogP value are able to stain Gram-positive bacteria. Meanwhile, one of the presented AIEgens (TTPy) can generate reactive oxygen species (ROS) in extraordinarily high efficiency under white light irradiation due to the smaller singlet-triplet energy gap. Thanks to the NIR emission, excellent specificity to Gram-positive bacteria, and effective ROS generation efficiency, TTPy has been proved to perform well in selective photodynamic killing of Gram-positive bacteria in vitro, such as S. aureus and S. epidermidis, even in S. aureus-infected rat wounds.


Asunto(s)
Antibacterianos/química , Antibacterianos/farmacología , Bacterias Grampositivas/efectos de los fármacos , Bacterias Grampositivas/efectos de la radiación , Viabilidad Microbiana/efectos de los fármacos , Viabilidad Microbiana/efectos de la radiación , Animales , Bacterias Grampositivas/fisiología , Ratas , Relación Estructura-Actividad , Factores de Tiempo
13.
Org Biomol Chem ; 17(13): 3356-3360, 2019 03 27.
Artículo en Inglés | MEDLINE | ID: mdl-30865754

RESUMEN

A novel HTIB-promoted direct intramolecular dehydrogenative C-S bond coupling reaction of thioamides has been developed to provide 1,3-benzothiazine derivatives in good yields. The reaction proceeds smoothly to reach completion at room temperature within 1 min under metal-free conditions. This protocol provides a mild and efficient strategy for the synthesis of six-membered N,S-containing heterocycles. Preliminary mechanistic studies indicate that a spirocyclic intermediate might be involved.

14.
Sensors (Basel) ; 19(23)2019 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-31766702

RESUMEN

The progress of science and technology and the expansion of the Internet of Things make the information transmission between communication infrastructure and wireless sensors become more and more convenient. For the power-limited wireless sensors, the life time can be extended through the energy-harvesting technique. Additionally, wireless sensors can use the unauthored spectrum resource to complete certain information transmission tasks based on cognitive radio. Harvesting enough energy from the environments, the wireless sensors, works as the second users (SUs) can lease spectrum resource from the primary user (PU) to finish their task and bring additional transmission cost to themselves. To minimize the overall cost of SUs and to maximize the spectrum profit of the PU during the information transmission period, we formulated a differential game model to solve the resource allocation problem in the cognitive radio wireless sensor networks with energy harvesting, considering the SUs as the game players. By solving the proposed resource allocation game model, we found the open loop Nash equilibrium solutions and feedback Nash equilibrium solutions for all SUs as the optimal control strategies. Ultimately, series numerical simulation experiments have been made to demonstrate the rationality and effectiveness of the game model.

15.
Soft Matter ; 13(42): 7804-7812, 2017 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-29067393

RESUMEN

This work involved the construction of pH-responsive self-assembly systems from a pH-sensitive four-arm carboxylate acid (4EOCOOH) and either the cationic single chain surfactant dodecyl trimethyl ammonium bromide (DTAB) or the cationic gemini surfactant hexamethylene-1,6-bis(dodecyldimethylammonium bromide) (12-6-12). It was found that the constructed oligomeric-like structures from the mixtures of 4EOCOOH with DTAB or 12-6-12 greatly enhance the aggregation ability of the mixtures, thus improving the pH-responsivity. In particular, surfactant concentrations significantly affect the pH-responsivity at a fixed 4EOCOOH concentration. At higher surfactant concentrations, the pH-responsivity is suppressed, while at lower surfactant concentrations, the mixed aggregates gradually change from micelles to unstable large spherical aggregates or vesicles, and then to stable spherical aggregates, with decreasing pH. Moreover, the surfactant/4EOCOOH systems have different solubilization abilities for three hydrophobic drugs. For quercetin and baicalein, the systems support much better solubilization at lower pH values, while for indomethacin, the systems show better solubilization at higher pH values. In particular, compared with DTAB, 12-6-12 is more efficient in constructing pH-responsive systems, and the 12-6-12/4EOCOOH mixture shows better ability for solubilizing hydrophobic drugs. This work will be helpful in the design of high-efficiency, pH-responsive surfactant systems for solubilizing hydrophobic drugs by simply mixing pH-sensitive molecules with surfactants.

17.
J Neurooncol ; 126(1): 11-17, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26514363

RESUMEN

Accumulative epidemiological evidence suggests that single nucleotide polymorphisms (SNPs) in genes involved in homologous recombination (HR) DNA repair pathway play an important role in glioma susceptibility. However, the effects of such SNPs on glioma risk remain unclear. We used a used a candidate pathway-based approach to elucidate the relationship between glioma risk and 12 putative functional SNPs in genes involved in the HR pathway. Genotyping was conducted on 771 histologically-confirmed glioma patients and 752 cancer-free controls from the Chinese Han population. Odds ratios (OR) were calculated both for each SNP individually and for grouped analyses, examining the effects of the numbers of adverse alleles on glioma risk, and evaluated their potential gene-gene interactions using the multifactor dimensionality reduction (MDR). In the single-locus analysis, two variants, the NBS1 rs1805794 (OR 1.42, 95% CI 1.15-1.76, P = 0.001), and RAD54L rs1048771 (OR 1.61, 95% CI 1.17-2.22, P = 0.002) were significantly associated with glioma risk. When we examined the joint effects of the risk-conferring alleles of these three SNPs, we found a significant trend indicating that the risk increases as the number of adverse alleles increase (P = 0.005). Moreover, the MDR analysis suggested a significant three-locus interaction model involving NBS1 rs1805794, MRE11 rs10831234, and ATM rs227062. These results suggested that these variants of the genes involved in the HR pathway may contribute to glioma susceptibility.


Asunto(s)
Neoplasias Encefálicas/genética , Predisposición Genética a la Enfermedad/genética , Glioma/genética , Polimorfismo de Nucleótido Simple/genética , Reparación del ADN por Recombinación/genética , Transducción de Señal/genética , Transducción de Señal/inmunología , Adolescente , Adulto , Pueblo Asiatico/etnología , Pueblo Asiatico/genética , Proteínas de la Ataxia Telangiectasia Mutada/genética , Estudios de Casos y Controles , Femenino , Frecuencia de los Genes , Estudios de Asociación Genética , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Adulto Joven
18.
Soft Matter ; 12(5): 1579-85, 2016 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-26660592

RESUMEN

In this work we report the chain length dependent behavior of the nonamphiphilic supramolecular building blocks based on the host-guest inclusion complexes of alkanes and ß-cyclodextrins (ß-CD). (1)H NMR, ESI-MS, and SAXS measurements verified that upon increasing the chain length of alkanes, the building blocks for vesicle formation changed from channel type 2alkane@2ß-CD via channel type alkane@2ß-CD to non-channel type 2alkane@2ß-CD. FT-IR and TGA experiments indicated that hydrogen bonding is the extensive driving force for vesicle formation. It revealed that water molecules are involved in vesicle formation in the form of structural water. Upon changing the chain length, the average number of water molecules associated with per building block is about 16-21, depending on the chain length.


Asunto(s)
Alcanos/química , beta-Ciclodextrinas/química , Dispersión Dinámica de Luz , Enlace de Hidrógeno , Microscopía de Fuerza Atómica , Dispersión del Ángulo Pequeño , Espectroscopía Infrarroja por Transformada de Fourier , Agua/química , Difracción de Rayos X
20.
J Nat Prod ; 78(1): 10-6, 2015 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-25555195

RESUMEN

Esophageal cancer is the eighth most common cancer in the world and ranks as the sixth leading cause of cancer-related mortality. Esophageal cancer has a poor prognosis partially due to its low sensitivity to chemotherapy agents, and the development of new therapeutic agents is urgently needed. Here, the antitumor activity of a natural ent-kaurane diterpenoid, xerophilusin B (1), which was isolated from Isodon xerophilus, a perennial herb frequently used in Chinese folk medicine for tumor treatment, was investigated. Compound 1 exhibited antiproliferative effects against esophageal squamous cell carcinoma (ESCC) cell lines in a time- and dose-dependent manner with lower toxicity against normal human and murine cell lines. In vivo studies demonstrated that 1 inhibited tumor growth of a human esophageal tumor xenograft in BALB/c nude mice without significant secondary adverse effects, indicating its safety in treating ESCC. Furthermore, 1 induced G2/M cell cycle arrest and promoted apoptosis through mitochondrial cytochrome c-dependent activation of the caspase-9 and caspase-3 cascade pathway in ESCC cell lines. In conclusion, the observations herein reported showed that 1 is a potential chemotherapeutic agent for ESCC and merits further preclinical and clinical investigation for cancer drug development.


Asunto(s)
Carcinoma de Células Escamosas/tratamiento farmacológico , Diterpenos de Tipo Kaurano/farmacología , Diterpenos/farmacología , Neoplasias Esofágicas/tratamiento farmacológico , Puntos de Control de la Fase G2 del Ciclo Celular/efectos de los fármacos , Isodon/química , Animales , Antineoplásicos Fitogénicos/farmacología , Apoptosis/efectos de los fármacos , Western Blotting , Caspasa 3/metabolismo , Caspasa 9/metabolismo , Diterpenos/química , Diterpenos/aislamiento & purificación , Diterpenos de Tipo Kaurano/química , Diterpenos de Tipo Kaurano/aislamiento & purificación , Carcinoma de Células Escamosas de Esófago , Femenino , Humanos , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Estructura Molecular
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