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1.
Phys Rev Lett ; 132(8): 081601, 2024 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-38457701

RESUMEN

We consider a model of Parisi where a single particle hops on an infinite-dimensional hypercube, under the influence of a uniform but disordered magnetic flux. We reinterpret the hypercube as the Fock-space graph of a many-body Hamiltonian and the flux as a frustration of the return amplitudes in Fock-space. We will identify the set of observables that have the same correlation functions as the double-scaled Sachdev-Ye-Kitaev (DS-SYK) model, and hence the hypercube model is an equally good quantum model for near-AdS_{2}/near-CFT_{1} (NAdS_{2}/NCFT_{1}) holography. Unlike the SYK model, the hypercube Hamiltonian is not p local. Instead, the SYK model can be understood as a Fock-space model with similar frustrations. Hence we propose this type of Fock-space frustration as the broader characterization for NAdS_{2}/NCFT_{1} microscopics, which encompasses the hypercube and the DS-SYK models as two specific examples. We then speculate on the possible origin of such frustrations.

2.
Phys Rev Lett ; 128(8): 081601, 2022 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-35275644

RESUMEN

We show that, after ensemble averaging, the low temperature phase of a conjugate pair of uncoupled, quantum chaotic, non-Hermitian systems such as the Sachdev-Ye-Kitaev (SYK) model or the Ginibre ensemble of random matrices is dominated by saddle points that couple replicas and conjugate replicas. This results in a nearly flat free energy that terminates in a first-order phase transition. In the case of the SYK model, we show explicitly that the spectrum of the effective replica theory has a gap. These features are strikingly similar to those induced by wormholes in the gravity path integral which suggests a close relation between both configurations. For a nonchaotic SYK, the results are qualitatively different: the spectrum is gapless in the low temperature phase and there is an infinite number of second order phase transitions unrelated to the restoration of replica symmetry.

3.
Nanotechnology ; 34(3)2022 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-36219885

RESUMEN

The serious side effects of cisplatin hindered its clinical application and the nanotechnology might be the potential strategy to address the limitation. However, rapid clearance in the blood circulation and ineffective controlled drug release from nanocarriers hamper the therapeutic efficacy of the nano-delivery system. We constructed a tumor microenvironment and redox dual stimuli-responsive nano-delivery system PEG-c-(BPEI-SS-Pt) by cross-linking the disulfide-containing polymeric conjugate BPEI-SS-Pt with the dialdehyde group-modified PEG2000via Schiff base. After optimized the cross-linking time, 72 h was selected to get the nano-delivery system.1H NMR and drug release assays showed that under the acidic tumor microenvironment (pH 6.5-6.8), the Schiff base can be broken and detached the PEG cross-linked outer shells, displaying the capability to release the drugs with a sequential pH- and redox-responsive manner. Moreover, PEG-c-(BPEI-SS-Pt) showed more effective anti-tumor therapeutic efficacyin vivowith no significant side effects when compared with the drug of cisplatin used in the clinic. This strategy highlights a promising platform with the dual stimuli-responsive profile to achieve better therapeutic efficacy and minor side effects for platinum-based chemotherapy.


Asunto(s)
Nanopartículas , Neoplasias , Humanos , Cisplatino/farmacología , Cisplatino/uso terapéutico , Microambiente Tumoral , Bases de Schiff , Nanopartículas/química , Polímeros/química , Sistemas de Liberación de Medicamentos , Oxidación-Reducción , Neoplasias/tratamiento farmacológico , Concentración de Iones de Hidrógeno , Línea Celular Tumoral
4.
Endocr J ; 69(2): 217-224, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35228410

RESUMEN

Di-(2-ethylhexyl) phthalate (DEHP) is extensively used in many personal care and consumer products, which results in widespread human exposure. Limited studies have suggested that exposure to DEHP may affect thyroid function, but little is known about the effect and mechanisms of DEHP exposure on the hypothalamic-pituitary-thyroid axis (HPTA). The present study was conducted to elucidate the potential mechanisms underlying DEHP disrupting the function of the HPTA. DEHP was administered to Wistar rats by gavage at 0, 5, 50, and 500 mg/kg/day for consecutive 28 days and then the rats were sacrificed within 24 h following the last dose. The hormone levels of HPTA were quantified with radioimmunoassay and enzyme-linked immunosorbent assay, the protein levels of thyrotropin-releasing hormone receptor (TRHR) and thyroid-stimulating hormone receptor (TSHR) were analyzed by Western blot and immunohistochemistry, and the expression levels of TRHR and TSHR mRNA were measured by quantitative real-time PCR. The low dose of DEHP increased the body weights of rats. Serum levels of T3, T4, FT3 and FT4 as well as protein and mRNA levels of TSHR decreased in rats treated with 50 mg/kg or 500 mg/kg DEHP compared with those of controls. Although the protein levels of TRH in the hypothalamus or protein and mRNA levels of TRHR in pituitary were up-regulated, serum levels of TSH did not change statistically in rats treated with DEHP. Therefore, DEHP can produce thyroid toxicity and may interfere with the secretion of pituitary TSH. In conclusion, DEHP could interfere with the balance of HPTA of adolescent rats, and disturb the homeostasis of thyroid related hormones and the expression levels of receptors.

5.
Nanotechnology ; 31(32): 325101, 2020 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-32325436

RESUMEN

Polyethylenimine (PEI), a kind of cationic non-viral gene delivery vector, is capable of stable and efficient transgene expression for gene delivery. However, low transfection efficiency in vivo along with high toxicity limited the further application of gene therapy in the clinic. To enhance gene transfection performance and reduce cytotoxicity of polyethylenimine, branched polyethylenimine-derived cationic polymers BPEI25 k-man-S/L/M/H with different grafting degree with mannitol moieties were prepared and the transfection efficiency was evaluated. Among them, BPEI25 k-man-L showed the best transfection efficiency, lower toxicity, and significantly enhanced long-term systemic transgene expression for 96 h in vivo even at a single-dose administration. The results of cellular uptake mechanism and western-blot experiments revealed that the mannitol modification of BPEI25 k induced and up-regulated the phosphorylation of caveolin-1 and thus enhanced the caveolae-mediated cellular uptake. This class of gene delivery system highlights a paradigmatic approach for the development of novel and safe non-viral vectors for gene therapy.


Asunto(s)
Caveolina 1/metabolismo , Vectores Genéticos/administración & dosificación , Manitol/química , Polietileneimina/química , Animales , Células COS , Chlorocebus aethiops , Técnicas de Transferencia de Gen , Vectores Genéticos/química , Células HEK293 , Células HeLa , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Fosforilación , Transfección
6.
J Nanobiotechnology ; 18(1): 26, 2020 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-32005170

RESUMEN

BACKGROUND: Gene therapy remains a significant challenge due to lots of barriers limiting the genetic manipulation technologies. As for non-viral delivery vectors, they often suffer insufficient performance due to inadequate cellular uptake and gene degradation in endosome or lysosome. The importance of overcoming these conserved intracellular barriers is increasing as the delivery of genetic cargo. RESULTS: A surface-functionalized non-viral vector involving the biomimetic mannitol moiety is initiated, which can control the cellular uptake and promote the caveolae-mediated pathway and intracellular trafficking, thus avoiding acidic and enzymatic lysosomal degradation of loaded gene internalized by clathrin-mediated pathway. Different degrees of mannitol moiety are anchored onto the surface of the nanoparticles to form bio-inspired non-viral vectors and CaP-MA-40 exhibits remarkably high stability, negligible toxicity, and significantly enhanced transgene expression both in vitro and in vivo. CONCLUSIONS: This strategy highlights a paradigmatic approach to construct vectors that need precise intracellular delivery for innovative applications.


Asunto(s)
Fosfatos de Calcio/química , Vectores Genéticos/química , Vectores Genéticos/metabolismo , Nanopartículas/química , Transgenes , Caveolas/metabolismo , Línea Celular , Permeabilidad de la Membrana Celular , Clatrina/metabolismo , Endosomas/metabolismo , Regulación Viral de la Expresión Génica , Técnicas de Transferencia de Gen , Terapia Genética , Humanos , Lisosomas/metabolismo , Manitol/metabolismo , Transducción de Señal , Propiedades de Superficie , Transducción Genética , Transfección
7.
Nanotechnology ; 29(8): 085101, 2018 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-29256442

RESUMEN

Non-viral nanovectors have attracted much attention owing to their ability to condense genetic materials and their ease of modification. However, their poor stability, low biocompatibility and gene degradation in endosomes or lysosomes has significantly hampered their application in vivo and in the clinic. In an attempt to overcome these difficulties a series of bovine serum albumin (BSA)-calcium phosphate (CaP) nanoparticles were constructed. The CaP condenses with DNA to form nanocomplexes coated with a biomimetic corona of BSA. Such complexes may retain the inherent endocytosis profile of BSA, with improved biocompatibility. In particular the transgene performance may be enhanced by stimulating the cellular uptake pathway via caveolae-mediated endocytosis. Two methods were employed to construct and optimize the formulation of BSA-CaP nanomaterials. The optimized BSA-CaP-50-M2 nanoparticles prepared by our second method exhibited good stability, negligible cytotoxicity and enhanced transgene performance with long-term expression for 72 h in vivo even with a single dose. Determination of the cellular uptake pathway and Western blot revealed that cellular uptake of the designed BSA-CaP-50-M2 nanoparticles was mainly via caveolae-mediated endocytosis in a non-degradative pathway in which the biomimetic uptake profile of BSA was retained.


Asunto(s)
Fosfatos de Calcio/química , Caveolas/metabolismo , Endocitosis , Nanoestructuras/química , Corona de Proteínas/metabolismo , Albúmina Sérica Bovina/química , Transgenes , Animales , Bovinos , Caveolina 1/metabolismo , Muerte Celular , ADN/química , Proteínas Fluorescentes Verdes/metabolismo , Células HEK293 , Humanos , Masculino , Ratones Desnudos , Tamaño de la Partícula , Fosforilación , Distribución Tisular
8.
Endocr J ; 65(3): 261-268, 2018 03 28.
Artículo en Inglés | MEDLINE | ID: mdl-29225205

RESUMEN

Di-(2-ethylhexyl) phthalate (DEHP) is extensively used in many personal care and consumer products, which has resulted in widespread human exposure. Limited studies have suggested that exposure to DEHP may affect thyroid function, but little is known about the effect and mechanisms of DEHP exposure on the hypothalamic-pituitary-thyroid axis (HPTA). The present study was conducted to elucidate the potential mechanisms in which DEHP disrupts the function of the HPTA. Wistar rats were administered DEHP by gavage at 0, 5, 50, and 500 mg/kg/day for 28 days and then sacrificed within 24 h following the last dose. Hormones of HPTA was quantified with radioimmunoassay and enzyme-linked immunosorbent assay, protein levels of thyrotropin-releasing hormone receptor (TRHR) and thyroid-stimulating hormone receptor (TSHR) were analyzed by Western blot and immunohistochemistry, expression levels of TRHR and TSHR mRNA were measured by quantitative real-time PCR. Rats treated with DEHP resulted in increased bodyweight, on the HPTA, down-regulated the protein levels of TRH in the hypothalamus, up-regulated the protein and mRNA levels of TRHR in the pituitary, down-regulated mRNA expression of TSHR in the thyroid, while the difference of TSH in various dose groups was not statistically significant and T3, T4, FT3, FT4 levels in serum were decreased compared with control. DEHP could interfere with the balance of HPTA of adolescent rats, and increase the body weight, down-regulate the homeostasis of thyroid related hormones and receptors expression levels.


Asunto(s)
Dietilhexil Ftalato/farmacología , Disruptores Endocrinos/farmacología , Sistema Hipotálamo-Hipofisario/efectos de los fármacos , Receptores de Hormona Liberadora de Tirotropina/metabolismo , Receptores de Tirotropina/metabolismo , Glándula Tiroides/efectos de los fármacos , Animales , Femenino , Sistema Hipotálamo-Hipofisario/metabolismo , Masculino , Ratas , Ratas Wistar , Glándula Tiroides/metabolismo , Hormonas Tiroideas/sangre , Hormona Liberadora de Tirotropina/sangre
9.
Bioorg Med Chem Lett ; 27(4): 1003-1006, 2017 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-28087273

RESUMEN

The covalently cross-linked chitosan-poly(ethylene glycol)1540 derivatives have been developed as a controlled release system with potential for the delivery of protein drug. The swelling characteristics of the hydrogels based on these derivatives as the function of different PEG content and the release profiles of a model protein (bovine serum albumin, BSA) from the hydrogels were evaluated in simulated gastric fluid with or without enzyme in order to simulate the gastrointestinal tract conditions. The derivatives cross-linked with difunctional PEG1540-dialdehyde via reductive amination can swell in alkaline pH and remain insoluble in acidic medium. The cumulative release amount of BSA was relatively low in the initial 2h and increased significantly at pH 7.4 with intestinal lysozyme for additional 12h. The results proved that the release-and-hold behavior of the cross-linked CS-PEG1540H-CS hydrogel provided a swell and intestinal enzyme controlled release carrier system, which is suitable for oral protein drug delivery.


Asunto(s)
Aldehídos/química , Aminas/química , Quitosano/química , Portadores de Fármacos , Polietilenglicoles/química , Albúmina Sérica Bovina/administración & dosificación , Materiales Biocompatibles , Células CACO-2 , Secuencia de Carbohidratos , Humanos , Oxidación-Reducción , Espectroscopía de Protones por Resonancia Magnética , Espectroscopía Infrarroja por Transformada de Fourier
10.
Bioorg Med Chem Lett ; 26(10): 2401-2407, 2016 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-27072908

RESUMEN

Cholesterol derivatives M1-M6 as synthetic cationic lipids were designed and the biological evaluation of the cationic liposomes based on them as non-viral gene delivery vectors were described. Plasmid pEGFP-N1, used as model gene, was transferred into 293T cells by cationic liposomes formed with M1-M6 and transfection efficiency and GFP expression were tested. Cationic liposomes prepared with cationic lipids M1-M6 exhibited good transfection activity, and the transfection activity was parallel (M2 and M4) or superior (M1 and M6) to that of DC-Chol derived from the same backbone. Among them, the transfection efficiency of cationic lipid M6 was parallel to that of the commercially available Lipofectamine2000. The optimal formulation of M1 and M6 were found to be at a mol ratio of 1:0.5 for cationic lipid/DOPE, and at a N/P charge mol ratio of 3:1 for liposome/DNA. Under optimized conditions, the efficiency of M1 and M6 is greater than that of all the tested commercial liposomes DC-Chol and Lipofectamine2000, even in the presence of serum. The results indicated that M1 and M6 exhibited low cytotoxicity, good serum compatibility and efficient transfection performance, having the potential of being excellent non-viral vectors for gene delivery.


Asunto(s)
Colesterol/química , Terapia Genética/métodos , Lípidos/química , Liposomas/química , Relación Estructura-Actividad , Colesterol/análogos & derivados , Técnicas de Transferencia de Gen , Proteínas Fluorescentes Verdes/metabolismo , Células HEK293 , Humanos , Lípidos/síntesis química , Tamaño de la Partícula , Fosfatidiletanolaminas/química , Suero/química , Transfección/métodos
11.
Biol Pharm Bull ; 39(7): 1112-20, 2016 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-27118165

RESUMEN

In this work two novel cationic lipids using natural tartaric acid as linking backbone were synthesized. These cationic lipids were simply constructed by tartaric acid backbone using head group 6-aminocaproic acid and saturated hydrocarbon chains dodecanol (T-C12-AH) or hexadecanol (T-C16-AH). The physicochemical properties, gel electrophoresis, transfection activities, and cytotoxicity of cationic liposomes were tested. The optimum formulation for T-C12-AH and T-C16-AH was at cationic lipid/dioleoylphosphatidylethanolamine (DOPE) molar ratio of 1 : 0.5 and 1 : 2, respectively, and N/P charge molar ratio of 1 : 1 and 1 : 1, respectively. Under optimized conditions, T-C12-AH and T-C16-AH showed effective gene transfection capabilities, superior or comparable to that of commercially available transfecting reagent 3ß-[N-(N',N'-dimethylaminoethyl)carbamoyl]cholesterol (DC-Chol) and N-[2,3-dioleoyloxypropyl]-N,N,N-trimethylammonium chloride (DOTAP). The results demonstrated that the two novel tartaric acid-based cationic lipids exhibited low toxicity and efficient transfection performance, offering an excellent prospect as nonviral vectors for gene delivery.


Asunto(s)
Técnicas de Transferencia de Gen , Lípidos/química , Tartratos/química , Ácido Aminocaproico , Supervivencia Celular/efectos de los fármacos , ADN/administración & dosificación , ADN/química , Proteínas Fluorescentes Verdes/genética , Células HEK293 , Células HeLa , Humanos , Liposomas/química , Liposomas/farmacología
12.
Biomed Chromatogr ; 29(9): 1422-7, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25728168

RESUMEN

A rapid, sensitive HPLC-MS/MS method was established and validated to assay the concentration and pharmacokinetic profile of MT502, a promising hypnotic drug. The plasma sample was treated by a liquid-liquid extraction and separated on a kromasil C18 column at an isocratic flow rate of 0.3 mL/min using methanol and 0.1% formic acid in water (75:25, v/v) as mobile phase. The mass spectrometric detection was carried out using a triple-quadrupole system via positive electrospray ionization. Multiple reaction monitoring was used for quantitation of m/z transitions from 261 to 188 for MT502 and from 247 to 188 for MT501 (internal standard). Good linearity was achieved over the concentration range of 1-1000 ng/mL and 10-5000 ng/mL with lower limit of quantification of 0.30 and 0.80 ng/mL. The intra- and inter-day precisions, accuracy, recovery and stability were satisfactory for the concentration test. The above method can be used for a pharmacokinetic study at doses of 1, 5 and 20 mg/kg. Results indicated that MT502 had rapid absorption, rapid elimination and linear pharmacokinetic properties within the range of the tested intragastric dose. This developed HPLC-MS/MS method was successfully applied to a pharmacokinetic study of MT502 for the first time and was demonstrated to be simple and sensitive.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Hipnóticos y Sedantes/análisis , Espectrometría de Masas en Tándem/métodos , Animales , Hipnóticos y Sedantes/farmacocinética , Masculino , Ratas , Ratas Sprague-Dawley
13.
Bioorg Med Chem Lett ; 24(20): 4794-7, 2014 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-25248683

RESUMEN

PC407 is an effective COX-2 inhibitor in non-steroidal anti-inflammatory drug development but the poor solubility limits their usefulness. The aim of the study was to prepare and evaluate 4-oxo-4-[4-(5-(naphthalen-2-yl)-3-(trifluoromethyl)-1H-pyrazol-1-yl)benzenesulfonamido]butyrate disodium, a derivative of PC407 with enhanced water solubility for injectable formulation. The prepared derivative displayed interesting high aqueous solubility (20.3 mg/mL, much superior to the parent compound PC407, 1.6 µg/mL) with confirmed in vivo analgesic activity. This derivative represents the profiles of prodrug and potential candidate of PC407 for the development of injectable COX-2 inhibitor due to extraordinary water solubility, low toxicity, and impressive analgesic activity.


Asunto(s)
Inhibidores de la Ciclooxigenasa 2/administración & dosificación , Inhibidores de la Ciclooxigenasa 2/farmacología , Ciclooxigenasa 2/metabolismo , Profármacos/farmacología , Pirazoles/farmacología , Sulfonamidas/farmacología , Administración Intravenosa , Animales , Inhibidores de la Ciclooxigenasa 2/química , Relación Dosis-Respuesta a Droga , Femenino , Masculino , Estructura Molecular , Profármacos/administración & dosificación , Profármacos/química , Pirazoles/administración & dosificación , Pirazoles/química , Ratas , Solubilidad , Relación Estructura-Actividad , Sulfonamidas/administración & dosificación , Sulfonamidas/química , Agua/química
14.
Phytomedicine ; 128: 155521, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38489891

RESUMEN

BACKGROUND: The ancient Chinese herb Salvia miltiorrhiza Bunge (Danshen), plays the important role in cardiovascular and cerebrovascular disease. Furthermore, Danshen could also be used for curing carcinogenesis. Up to now, the anti-tumor effects of the main active constituents of Danshen have made great progress. However, the bioavailability of the active constituents of Danshen were restricted by their unique physical characteristics, like low oral bioavailability, rapid degradation in vivo and so on. PURPOSE: With the leap development of nano-delivery systems, the shortcomings of the active constituents of Danshen have been greatly ameliorated. This review tried to summarize the recent progress of the active constituents of Danshen based delivery systems used for anti-tumor therapeutics. METHODS: A systematic literature search was conducted using 5 databases (Embase, Google scholar, PubMed, Scopus and Web of Science databases) for the identification of relevant data published before September 2023. The words "Danshen", "Salvia miltiorrhiza", "Tanshinone", "Salvianolic acid", "Rosmarinic acid", "tumor", "delivery", "nanomedicine" and other active ingredients contained in Danshen were searched in the above databases to gather information about pharmaceutical decoration for the active constituents of Danshen used for anti-tumor therapeutics. RESULTS: The main extracts of Danshen could inhibit the proliferation of tumor cells effectively and a great deal of studies were conducted to design drug delivery systems to ameliorate the anti-tumor effect of the active contents of Danshen through different ways, like improving bioavailability, increasing tumor targeting ability, enhancing biological barrier permeability and co-delivering with other active agents. CONCLUSION: This review systematically represented recent progress of pharmaceutical decorations for the active constituents of Danshen used for anti-tumor therapeutics, revealing the diversity of nano-decoration skills and trying to inspire more designs of Danshen based nanodelivery systems, with the hope that bringing the nanomedicine of the active constituents of Danshen for anti-tumor therapeutics from bench to bedside in the near future.


Asunto(s)
Antineoplásicos Fitogénicos , Medicamentos Herbarios Chinos , Salvia miltiorrhiza , Salvia miltiorrhiza/química , Medicamentos Herbarios Chinos/administración & dosificación , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/química , Humanos , Antineoplásicos Fitogénicos/administración & dosificación , Antineoplásicos Fitogénicos/farmacología , Sistemas de Liberación de Medicamentos , Animales , Neoplasias/tratamiento farmacológico , Sistema de Administración de Fármacos con Nanopartículas/química , Nanopartículas/química
15.
Adv Healthc Mater ; 11(12): e2102479, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35182456

RESUMEN

Primary tumor organoids (PTOs) growth in hydrogels have emerged as an important in vitro model that recapitulates many characteristics of the native tumor tissue, and have important applications in fundamental cancer research and for the development of useful therapeutic treatment. This paper begins with reviewing the methods of isolation of primary tumor cells. Then, recent advances on the instructive hydrogels as biomimetic extracellular matrix for primary tumor cell culture and construction of PTO models are summarized. Emerging microtechnology for growth of PTOs in microscale hydrogels and the applications of PTOs are highlighted. This paper concludes with an outlook on the future directions in the investigation of instructive hydrogels for PTO growth.


Asunto(s)
Matriz Extracelular , Hidrogeles , Técnicas de Cultivo de Célula , Microtecnología , Organoides
16.
Mitochondrial DNA B Resour ; 5(1): 551-553, 2020 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-33366642

RESUMEN

The complete mitochondrial genome of the Annamanum lunulatum is 15,610 bp in length, which contains 13 protein-coding genes, 22 transfer RNAs, two ribosomal RNAs, and the A + T-rich region. The arrangement of genes is identical to all know longhorn beetles mitochondrial genomes. The overall AT content of the mitochondrial genome is 75.3%, whereas the AT content of A + T-rich region is 84.3%. In ML and BI phylogenetic analyses, A. lunulatum is a sister clade to Blepephaeus succinctor, and the monophyly of Lamiinae is supported.

17.
Mitochondrial DNA B Resour ; 5(3): 3079-3081, 2020 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-33458066

RESUMEN

The mitochondrial genome sequence of Xanthomantis bimaculata (Mantodea: Iridopterygidae) from Yunnan, China is a circular molecule with the typical insect mitochondrial gene arrangement, which is 15,941 bp in length and contains 22 tRNAs, two rRNAs, 13 protein-coding genes, and one control region. The overall AT content of the mitogenome is 73.12% (A = 37.58%, T = 35.54%, C = 16.54%, G = 10.34%). In BI and ML phylogenetic analyses, X. bimaculata was a sister clade to Sceptuchus simplex. The monophyly of the families Iridopterygidae, Thespidae and Liturgusidae were supported.

18.
Int J Pharm ; 580: 119190, 2020 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-32151664

RESUMEN

Cisplatin is one of the most widely used platinum-based anticancer chemotherapeutic drugs. However, its low solubility, serious side effects and the development of cisplatin resistance limit its further use in the clinic. Controlling the delivery and release of cisplatin at the targeted site efficiently is a meaningful way to overcome these undesirable side effects of cisplatin. Herein, a tumor targeted and stimuli responsive nano-delivery system for cisplatin was constructed using branched polyethyleneimine (BPEI) as the backbone, disulfide bond as the redox-responsive covalent linker and hyaluronic acid (HA) as targeting recognition unit which can bind selectively to the receptor of CD44, which is highly expressed on the A549 tumor cells. The cisplatin-polyethyleneimine conjugate BPEI-SS-Pt was prepared and the drug loading of cisplatin was up to 32.66 ± 0.06%. After optimized the coating weight ratio of HA and BPEI-SS-Pt, the nanoparticle delivery system HA-(BPEI-SS-Pt)-1/4 outperformed with smaller particle size of 159.0 ± 21.0 nm, narrow polydispersity index (PDI) of 0.069 ± 0.022 and higher cisplatin loading of 29.23 ± 0.18%, showing specific tumor-targeting ability and redox-responsive drug release manner. Moreover, for the treatment of cancer in vivo, it achieved more effective antitumor performance along with minor side effects and systemic toxicity compared with cisplatin which is of great significance for the chemotherapeutic drug in the clinic.


Asunto(s)
Antineoplásicos/administración & dosificación , Cisplatino/administración & dosificación , Sistemas de Liberación de Medicamentos/métodos , Nanopartículas/administración & dosificación , Neoplasias/tratamiento farmacológico , Células A549 , Animales , Antineoplásicos/química , Antineoplásicos/metabolismo , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/fisiología , Cisplatino/química , Cisplatino/metabolismo , Relación Dosis-Respuesta a Droga , Humanos , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Nanopartículas/química , Nanopartículas/metabolismo , Neoplasias/metabolismo , Neoplasias/patología , Oxidación-Reducción/efectos de los fármacos , Resultado del Tratamiento , Ensayos Antitumor por Modelo de Xenoinjerto/métodos
19.
PeerJ ; 8: e9740, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32879803

RESUMEN

As a small order of Pterygota (Insecta), Ephemeroptera has almost 3,500 species around the world. Ephemerellidae is a widely distributed common group of Ephemeroptera. However, the relationship among Ephemerellidae, Vietnamellidae and Teloganellidae is still in dispute. In this study, we sequenced six complete mitogenomes of three genera from Ephemerellidae (Insecta: Ephemeroptera): Ephemerella sp. Yunnan-2018, Serratella zapekinae, Serratella sp. Yunnan-2018, Serratella sp. Liaoning-2019, Torleya grandipennis and T. tumiforceps. These mitogenomes were employed to reveal controversial phylogenetic relationships among the Ephemeroptera, with emphasis on the phylogenetic relationships among Ephemerellidae. The lengths of the six mayfly mitogenomes ranged from 15,134 bp to 15,703 bp. Four mitogenomes of Ephemerella sp. Yunnan-2018, Serratella zapekinae, Serratella sp. Yunnan-2018 and Serratella sp. Liaoning-2019 had 22 tRNAs including an inversion and translocation of trnI. By contrast, the mitogenomes of T. tumiforceps and T. grandipennis had 24 tRNAs due to an extra two copies of inversion and translocation of trnI. Within the family Ephemerellidae, disparate gene rearrangement occurred in the mitogenomes of different genera: one copy of inversion and translocation trnI in the genera Ephemerella and Serratella, and three repeat copies of inversion and translocation of trnI in the genus Torleya. A large non-coding region (≥200 bp) between trnS1 (AGN) and trnE was detected in T. grandipennis and T. tumiforceps. Among the phylogenetic relationship of the Ephemeroptera, the monophyly of almost all families except Siphlonuridae was supported by BI and ML analyses. The phylogenetic results indicated that Ephemerellidae was the sister clade to Vietnamellidae whereas Teloganellidae was not a sister clade of Ephemerellidae and Vietnamellidae.

20.
J Exp Clin Cancer Res ; 39(1): 42, 2020 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-32093760

RESUMEN

BACKGROUND: We have previously described CLDN6 as a tumor suppressor gene in breast cancer. Here, a new finding is that CLDN6 was upregulated under hypoxia, a commonly recognized factor that promotes tumor metastasis. In this study, we aim to explain this confusing finding and delineate the role of CLDN6 in the breast cancer metastasis induced by hypoxia. METHODS: RNAi and ChIP assays were used to confirm that CLDN6 is transcriptional regulated by HIF-1α. mRNA seq and KEGG analysis were performed to define the downstream pathways of CLDN6. The roles of the CLDN6/SENP1/HIF-1α signaling on tumor metastasis were evaluated by function experiments and clinical samples. Finally, the possible transcription factor of SENP1 was suspected and then validated by ChIP assay. RESULTS: We demonstrated a previously unrecognized negative feedback loop exists between CLDN6 and HIF-1α. CLDN6 was transcriptionally up-regulated by HIF-1α under hypoxia. On the other hand, in cytoplasm CLDN6 combines and retains ß-catenin, a transcription factor of SENP1, causing ß-catenin degradation and preventing its nuclear translocation. This process reduced SENP1 expression and prevented the deSUMOylation of HIF-1α, ultimately leading to HIF-1α degradation and breast cancer metastasis suppression. CONCLUSIONS: Our data provide a molecular mechanistic insight indicating that CLDN6 loss may lead to elevated HIF-1α-driven breast cancer metastasis in a SUMOylation-dependent manner.


Asunto(s)
Neoplasias de la Mama/patología , Claudinas/genética , Claudinas/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Animales , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Hipoxia de la Célula , Línea Celular Tumoral , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Retroalimentación Fisiológica , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Células MCF-7 , Ratones , Metástasis de la Neoplasia , Trasplante de Neoplasias , Proteolisis , Transducción de Señal/efectos de los fármacos , Sumoilación
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