Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 110
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Molecules ; 29(7)2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38611920

RESUMEN

Six new 2α-hydroxy ursane triterpenoids, 3α-cis-p-coumaroyloxy-2α,19α-dihydroxy-12-ursen-28-oic acid (1), 3α-trans-p-coumaroyloxy-2α,19α-dihydroxy-12-ursen-28-oic acid (2), 3α-trans-p-coumaroyloxy-2α-hydroxy-12-ursen-28-oic acid (3), 3ß-trans-p-coumaroyloxy-2α-hydroxy-12,20(30)-ursadien-28-oic acid (4), 3ß-trans-feruloyloxy-2α-hydroxy-12,20(30)-ursadien-28-oic acid (5), and 3α-trans-feruloyloxy-2α-hydroxy-12,20(30)-ursadien-28-oic acid (6), along with eleven known triterpenoids (7-17), were isolated from the leaves of Diospyros digyna. Their chemical structures were elucidated by comprehensive analysis of UV, IR, HRESIMS, and NMR spectra. All the isolated compounds were evaluated for their PTP1B inhibitory activity. 3ß-O-trans-feruloyl-2α-hydroxy-urs-12-en-28-oic acid (13) showed the best inhibition activity with an IC50 value of 10.32 ± 1.21 µM. The molecular docking study found that the binding affinity of compound 13 for PTP1B was comparable to that of oleanolic acid (positive control).


Asunto(s)
Diospyros , Triterpenos , Simulación del Acoplamiento Molecular , Hojas de la Planta , Hidroxiácidos , Triterpenos/farmacología
2.
Neuroimage ; 267: 119850, 2023 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-36603745

RESUMEN

Transcranial Magnetic Stimulation (TMS) is a non-invasive brain stimulation technique that uses a coil to induce an electric field (E-field) in the brain and modulate its activity. Many applications of TMS call for the repeated execution of E-field solvers to determine the E-field induced in the brain for different coil placements. However, the usage of solvers for these applications remains impractical because each coil placement requires the solution of a large linear system of equations. We develop a fast E-field solver that enables the rapid evaluation of the E-field distribution for a brain region of interest (ROI) for a large number of coil placements, which is achieved in two stages. First, during the pre-processing stage, the mapping between coil placement and brain ROI E-field distribution is approximated from E-field results for a few coil placements. Specifically, we discretize the mapping into a matrix with each column having the ROI E-field samples for a fixed coil placement. This matrix is approximated from a few of its rows and columns using adaptive cross approximation (ACA). The accuracy, efficiency, and applicability of the new ACA approach are determined by comparing its E-field predictions with analytical and standard solvers in spherical and MRI-derived head models. During the second stage, the E-field distribution in the brain ROI from a specific coil placement is determined by the obtained rows and columns in milliseconds. For many applications, only the E-field distribution for a comparatively small ROI is required. For example, the solver can complete the pre-processing stage in approximately 4 hours and determine the ROI E-field in approximately 40 ms for a 100 mm diameter ROI with less than 2% error enabling its use for neuro-navigation and other applications. Highlight: We developed a fast solver for TMS computational E-field dosimetry, which can determine the ROI E-field in approximately 40 ms for a 100 mm diameter ROI with less than 2% error.


Asunto(s)
Encéfalo , Estimulación Magnética Transcraneal , Humanos , Estimulación Magnética Transcraneal/métodos , Encéfalo/fisiología , Cabeza , Radiometría , Imagen por Resonancia Magnética/métodos
3.
Mod Pathol ; 36(12): 100332, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37716507

RESUMEN

Somatostatin receptor type 2 (SSTR2) and thyroid-stimulating hormone receptor (TSHR) display variable expression in primary thyroid tumors and have been implicated as theranostic targets. This study was designed to explore the differential expression of SSTR2 and TSHR in oncocytic (Hurthle cell) carcinoma (OC) vs oncocytic adenoma (OA). We performed a retrospective review for oncocytic neoplasms treated at our institution from 2012 to 2019. Formalin-fixed paraffin-embedded tissue blocks were used for tissue microarray construction. Tissue microarray blocks were cut into 5-µm sections and stained with anti-SSTR2 and anti-TSHR antibodies. Immunostains were analyzed by 3 independent pathologists. χ2 and logistic regression analysis were used to analyze clinical and pathologic variables. Sixty-seven specimens were analyzed with 15 OA and 52 OC. The mean age was 57 years, 61.2% were women, and 70% were White. SSTR2 positivity was noted in 2 OA (13%) and 15 OC (28%; 10 primary, 4 recurrent, and 1 metastatic) (P = .22). TSHR positivity was noted in 11 OA (73%) and 32 OC (62%; 31 primary and 1 metastatic) (P = .40). Those who presented with or developed clinical recurrence/metastasis were more likely to be SSTR2-positive (50% vs 21%; P = .04) and TSHR-negative (64.3% vs 28.9%; P = .02) than primary OC patients. Widely invasive OC was more likely to be SSTR2-positive compared to all other OC subtypes (minimally invasive and angioinvasive) (P = .003). For all patients with OC, TSHR positivity was inversely correlated with SSTR2 positivity (odds ratio, 0.12; CI, 0.03-0.43; P = .006). This relationship was not seen in the patients with OA (odds ratio, 0.30; CI, 0.01-9.14; P = .440). Our results show that recurrent/metastatic OC was more likely to be SSTR2-positive and TSHR-negative than primary OC. Patients with OC displayed a significant inverse relationship between SSTR2 and TSHR expression that was not seen in patients with OA. This may be a key relationship that can be used to prognosticate and treat OCs.


Asunto(s)
Neoplasias Glandulares y Epiteliales , Neoplasias de la Tiroides , Humanos , Femenino , Persona de Mediana Edad , Masculino , Receptores de Tirotropina , Pronóstico , Neoplasias de la Tiroides/patología , Tirotropina
4.
Lasers Surg Med ; 55(2): 178-189, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36573453

RESUMEN

BACKGROUND AND OBJECTIVES: Melasma is a refractory skin disease due to its complex pathogenesis and difficult treatment. Studies have found that human umbilical cord mesenchymal stem cell-derived exosomes (hUCMSC-Exos) could serve as a novel cell-free therapeutic strategy in regenerative and esthetic medicine. It could potentially treat melasma, but the skin barrier is a challenge. In this study, we aim to explore the safety and efficacy of hUCMSC-Exos in the treatment of melasma and the means to promote its percutaneous penetration. MATERIALS AND METHODS: In the animal study about the effect of penetration, percutaneous penetration of PKH67-labeled hUCMSC-Exos was studied under microneedles, 1565 nm nonablative fractional laser (NAFL), and a plasma named Peninsula Blue Aurora Shumin Master (PBASM) treatments, observed by confocal laser scanning microscopy. In the clinical application study, 60 patients with melasma treated in our department were divided into four groups. NAFL combined with normal saline treatment was used for Group A. Microneedles, NAFL, and PBASM combined with hUCMSC-Exos treatments were used for Groups B, C, and D, respectively. Each patient received four treatments at 1-month intervals. Assessments were done using the degree of pain posttreatment, melasma area and severity score, improvement rate, physician global assessment score, satisfaction, and complications. RESULTS: In the animal study about the effect of penetration, hUCMSC-Exos can penetrate the deep dermis under microneedles, NAFL, and PBASM treatments. In the clinical application study, compared with Group A, Groups B, C, and D showed significantly improved therapeutic effect and patient satisfaction (p < 0.05), and there was no significant difference among Groups B, C, and D.(p > 0.05). Patients in Group B reported higher pain levels than those in the other three groups (p < 0.05); the treatment experience of patients in Group D was better. CONCLUSION: hUCMSC-Exos can improve the symptoms of melasma safely and effectively. Compared with microneedles, NAFL and PBASM can also achieve a good effect toward promoting penetration. These findings are worthy of exploration and clinical application.


Asunto(s)
Exosomas , Melanosis , Células Madre Mesenquimatosas , Animales , Humanos , Piel , Melanosis/terapia , Células Madre
5.
J Insect Sci ; 23(3)2023 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-37352434

RESUMEN

Traditional chemical pesticides pose potential threats to human health, the environment, and food safety, and there is an urgent need to develop botanical pesticides that are easily degradable, renewable, and environmentally compatible. This research serves to detect the lethal impacts of Amanita pantherina(DC.:Fr) Schrmm.(Agaricales, Amanitaceae, Amanita), Amanita virgineoides Bas (Agaricales, Amanitaceae, Amanita), Coprinus comatus (O.F.Müll.) Pers. (Agaricales, Psathyrellaceae, Coprinus), Pycnoporus cinnabarinus(Jacq.:Fr) Karst (Polyporales, Polyporaceae, Polyporus) and Phallus rubicundus (Bosc) Fr. (Phallales, Phallaceae, Phallus) on Drosophila melanogaster(Diptera, Drosophilidae, Drosophila), including their effects on lifespan, fecundity, offspring growth and developmental characteristics, antioxidant enzyme activity, peroxide content, and the gene transcription associated with signaling pathways and lifespan of D. melanogaster. The results demonstrated that they all produced lethal effects on D. melanogaster. Female flies were more sensitive to the addition of macrofungi to their diet and have a shorter survival time than male flies. The toxic activity of A. pantherina-supplemented diet was the strongest, so that the D. melanogaster in this group had no offspring. The macrofungal-supplemented diets were able to significantly reduce the activity of antioxidant enzymes, accumulate peroxidation products, up-regulatd the transcription of genes related to signaling pathways, inhibit the expression of longevity genes, reduce the lifespan and fertility of D. melanogaster. Consequently, we hypothetically suggest that medicinal C. comatus, P. cinnabarinus and P. rubicundus hold the potential to be developed into an environmentally friendly biopesticide for fly killing.


Asunto(s)
Antioxidantes , Drosophila melanogaster , Masculino , Femenino , Humanos , Animales , Longevidad , Drosophila , Fertilidad
6.
Zhongguo Zhong Yao Za Zhi ; 48(7): 1885-1891, 2023 Apr.
Artículo en Zh | MEDLINE | ID: mdl-37282964

RESUMEN

To study the chemical constituents from the stems and leaves of Humulus scandens, this study isolated thirteen compounds by different chromatographic methods including silica gel column, ODS, Sephadex LH-20 and preparative HPLC. Based on comprehensive analysis, the chemical structures were elucidated and identified as citrunohin A(1), chrysosplenetin(2), casticin(3), neoechinulin A(4), ethyl 1H-indole-3-carboxylate(5), 3-hydroxyacetyl-indole(6),(1H-indol-3-yl) oxoacetamide(7), inonotusic acid(8), arteannuin B(9), xanthotoxol(10), α-tocopherol quinone(11), eicosanyl-trans-p-coumarate(12), and 9-oxo-(10E,12E)-octadecadienoic acid(13). Among them, compound 1 was a new dihydrochalcone, and the other compounds were obtained from H. scandens for the first time.


Asunto(s)
Chalconas , Medicamentos Herbarios Chinos , Humulus , Indoles , Medicamentos Herbarios Chinos/química
7.
Immunopharmacol Immunotoxicol ; 44(6): 1044-1057, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35848944

RESUMEN

BACKGROUND: Opioid prescription for inflammatory bowel disease (IBD)-related pain is on the rise. However, the use of strong opioids can result in severe complications, and even death, in IBD patients. This study aimed to define the role of fentanyl and morphine, two representative strong opioids, in the pathogenesis of dextran sodium sulfate (DSS)- and 2,4,6-trinitrobenzenesulfonic acid solution (TNBS)-induced colitis. METHOD: DSS and TNBS models were induced in C57BL/6J and Balb/c mice, respectively. Disease activity index (DAI), histopathology, enzyme-linked immunosorbent assay (ELISA), multiplex ELISA, and flow cytometry were performed to evaluate the effects of fentanyl and morphine. RESULT: Fentanyl exacerbated DSS- and TNBS-induced colitis, while morphine exhibited no significant immunomodulatory effect. Fentanyl and morphine had no obvious effects on the serum levels of adrenocorticotropic hormone (ACTH), glucocorticoid (GC), and prostaglandin E2 (PGE-2) in DSS and TNBS models. Fentanyl elevated the proportions of Th1 cells, µ-opioid receptor (MOR) + Th1 cells, and MOR + macrophages in the colonic mucosa of DSS-treated mice, and enhanced the proportions of Th1 cells, macrophages, MOR + Th1 cells, and MOR + macrophages in the colonic mucosa of TNBS-treated mice. We found that fentanyl upregulated the levels of inflammatory cytokines/chemokines in MOR + macrophages of the colonic lamina propria mononuclear cells (LPMCs) from DSS-treated mice, whereas it had no effect on the expression of most inflammatory cytokines/chemokines in MOR + macrophages in the colonic LPMCs from TNBS-treated mice. CONCLUSION: Our findings suggest that fentanyl exacerbates murine colitis via Th1 cell- and macrophage-mediated mechanisms, while morphine exhibits no significant immunomodulatory effect.


Asunto(s)
Fentanilo , Morfina , Ratones , Animales , Ácido Trinitrobencenosulfónico/toxicidad , Fentanilo/farmacología , Ratones Endogámicos C57BL , Morfina/farmacología
8.
Nanotechnology ; 30(20): 205401, 2019 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-30658349

RESUMEN

Splitting water is an important method for producing clean and sustainable hydrogen to replace finite fossil fuels in future energy systems. MoS2 is reported as a promising catalyst without noble metallic elements to accelerate the rate of the electrocatalytic hydrogen evolution reaction. However, there is a real need and strong demand for further improvement of the MoS2-based catalyst. In the present study, a novel amorphous phosphorus-doped MoS2 nanocomposite (P-MoS2) is prepared by a facile hydrothermal method. Compared with crystalline molybdenum disulfide, the amorphous P-doped MoS2 catalyst exhibits much better activity with a smaller Tafel slope of 39 mV dec-1. Moreover, good stability is also demonstrated over the P-MoS2 catalyst in acidic electrolyte. This highly active amorphous P-doped MoS2 catalyst is a promising candidate to facilitate the development of economical hydrogen production systems.

9.
Nanotechnology ; 31(10): 105707, 2019 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-31751973

RESUMEN

As highly efficient non-precious metal-based catalysts for the hydrogen evolution reaction (HER), molybdenum carbides have attracted much attention over the phase and structure modification for the improvement of HER performances. In this work, a novel strategy is proposed to modulate phases of molybdenum carbides by boron doping, so that the HER performances can be well controlled. After B-doping, the HER activity of the as-prepared B30 catalyst is significantly enhanced with a much smaller Tafel slope of 78 mV dec-1 than that of the blank one (134 mV dec-1), which originates from the increased amount of active sites, enhanced turnover frequency of each active site and reduced electron transfer resistance. Moreover, this work could broaden our view of phase regulation and provide more possible perspectives for the application in other fields.

10.
J Acoust Soc Am ; 145(6): EL521, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31255155

RESUMEN

Audio tagging aims to infer descriptive labels from audio clips and it is challenging due to the limited size of data and noisy labels. The solution to the tagging task is described in this paper. The main contributions include the following: an ensemble learning framework is applied to ensemble statistical features and the outputs from the deep classifiers, with the goal to utilize complementary information. Moreover, a sample re-weight strategy is employed to address the noisy label problem within the framework. The approach achieves a mean average precision of 0.958, outperforming the baseline system with a large margin.


Asunto(s)
Aprendizaje Profundo , Red Nerviosa/fisiología , Redes Neurales de la Computación , Neoplasias Cutáneas/fisiopatología , Biometría/métodos , Humanos
11.
Langmuir ; 34(12): 3694-3700, 2018 03 27.
Artículo en Inglés | MEDLINE | ID: mdl-29509429

RESUMEN

Maintaining colloidal stability in unfriendly environments while retaining surface chemical properties is challenging for fundamental science and crucial for many applications. Here, we report for the first time that by using a low concentration of poly(sodium 4-styrenesulfonate) (PSS), graphene-based amphiphilic Janus nanosheets (AJNs) can be stabilized in high salt brine (3 wt % NaCl and 0.5 wt % CaCl2), whereas the interfacial behavior of the nanosheets is not affected. The adsorption of PSS on the hydrophilic and hydrophobic surfaces of AJNs in brine was investigated experimentally and by molecular dynamics simulations. Simulations further showed that the spatial configuration of absorbed PSS molecules with sulfonate functional groups facing outward favored the generation of electrosteric repulsive interactions. Calculations of the interaction energy between PSS molecules and the nanosheet revealed surface charge as a key parameter to stabilize AJNs in the salt environment, as demonstrated by the case of graphene oxide with higher surface charge. Simulations were also used to examine the interfacial behavior of graphene-based AJNs in biphasic systems. The AJNs, which exhibited asymmetry in surface wettability, remained at the oil/brine interface because of PSS detachment from the hydrophobic surface. The results were subsequently experimentally confirmed, consistent with our previously reported graphene-based AJN fluid prepared in fresh water. The process was thermodynamically supported by the demonstrated negative change of Gibbs free energy. We believe that such a strategy could benefit for the stabilization of other AJNs with surface chemical accessibility under harsh conditions.

12.
Inorg Chem ; 57(17): 11027-11043, 2018 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-30129751

RESUMEN

With the aim of evaluating the potential of selenium-containing groups in developing electroluminescent (EL) materials, a series of asymmetric heteroleptic Ir(III) phosphorescent complexes (Ir-Se0F, Ir-Se1F, Ir-Se2F, and Ir-Se3F) have been synthesized by using 2-selenophenylpyridine and one ppy-type (ppy = 2-phenylpyridine) ligand with a fluorinated selenide group. To the best of our knowledge, these complexes represent unprecedented examples of asymmetric heteroleptic Ir(III) phosphorescent emitters bearing selenium-containing groups. Natural transition orbital (NTO) analysis based on optimized geometries of the first triplet state (T1) have shown that the phosphorescent emissions of these Ir(III) complexes dominantly show 3π-π* features of the 2-selenophenylpyridine ligand with slight metal to ligand charge transfer (MLCT) contribution. In comparison with their symmetric parent complex Ir-Se with two 2-selenophenylpyridine ligands, these asymmetric heteroleptic Ir(III) phosphorescent complexes can show much higher phosphorescent quantum yields (ΦP) of ca. 0.90. Both the hole- and electron-trapping ability of these Ir(III) phosphorescent complexes can be enhanced by selenophene and fluorinated selenide groups to improve their EL efficiencies. The EL abilities of these asymmetric heteroleptic Ir(III) phosphorescent emitters fall in the order Ir-Se3F > Ir-Se2F > Ir-Se1F > Ir-Se0F. The highest EL efficiencies have been achieved by Ir-Se3F in the solution-processed OLEDs with external quantum efficiency (ηext), current efficiency (ηL), and power efficiency (ηP) of 19.9%, 65.6 cd A-1, and 57.3 lm W-1, respectively. These encouraging EL results clearly indicate the great potential of selenium-containing groups in developing high-performance Ir(III) phosphorescent emitters.

13.
J Mater Sci Mater Med ; 26(4): 174, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25820665

RESUMEN

The antibiotic compound, rifampicin (RFP), was loaded into porous reinforced ß-tricalcium phosphate (ß-TCP) scaffolds using three different solution adsorption methods. This resulted in drug delivery systems (DDS) generated by vacuum adsorption (VA), dynamic adsorption (DA), and static adsorption (SA). In vitro examination of the drug loading and release profiles of the DDS indicated that the unit mass of RFP loaded into the scaffold by the VA method (0.44 mg/g) was higher than that achieved by SA (0.42 mg/g) or DA (0.38 mg/g) (P < 0.05). The mechanical strength had no significant change after RFP-loading (P > 0.05). Moreover, there were no significant differences among the mechanical strength of three ß-TCP DDS generated by loading RFP using SA, DA, and VA (P > 0.05). In vitro release testing showed an initial burst release of RFP from the three different DDS within the first 3 h and in the first 51 h, the cumulative release of RFP from VA-DDS, DA-DDS, and SA-DDS had reached 56.2, 83.6, and 88.6 %, respectively. Complete RFP release had occurred from VA-DDS, DA-DDS, and SA-DDS after 23, 17, and 15 days, respectively. As the VA-DDS method showed improved RFP loading and a more sustained drug release, this method is recommended for solution adsorption drug loading into porous ß-TCP scaffolds to form a DDS.


Asunto(s)
Sustitutos de Huesos/síntesis química , Fosfatos de Calcio/química , Implantes de Medicamentos/síntesis química , Rifampin/administración & dosificación , Rifampin/química , Andamios del Tejido , Absorción Fisicoquímica , Adsorción , Antibióticos Antituberculosos/administración & dosificación , Antibióticos Antituberculosos/química , Fuerza Compresiva , Difusión , Implantes de Medicamentos/administración & dosificación , Porosidad , Resistencia a la Tracción , Vacio
14.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 37(4): 430-4, 2015 Aug.
Artículo en Zh | MEDLINE | ID: mdl-26564460

RESUMEN

OBJECTIVE: To investigate the off-label use of oral glucocorticoids in outpatients. METHODS: The information of outpatient glucocorticoids prescriptions from January 1st to June 30th in 2012 were collected from the information system in our hospital, then the software of Excel was employed to statistically analyze the data including the amount of drugs used in different departments,as well as the age, sex, and diagnosis of the patients. The diagnoses were compared with those included in the labels approved by China Food and Drug Administration and US Food and Drug Administration and domestic and foreign guidelines. RESULTS: It was found that 16.53% of the cases were off-label use,and dexamethasone had the highest proportion (60.50%) of off-label use. Most of the off-label use had evidence support, such as multiple myeloma and myasthenia gravis, while some cases did not, such as epilepsy and sudden deafness. CONCLUSION: The management of off-label use should be further strengthened to promote the safe and rational use of glucocorticoids.


Asunto(s)
Uso Fuera de lo Indicado , Administración Oral , China , Epilepsia , Glucocorticoides , Humanos , Pacientes Ambulatorios
15.
Environ Sci Technol ; 48(8): 4515-20, 2014 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-24634979

RESUMEN

A series of V2O5/CeO2 catalysts with different potassium loadings were prepared to investigate alkali deactivations for selective catalytic reduction of NOx with NH3. An alkali poisoning mechanism could be attributed to surface acidity, reducibility, and NOx adsorption/desorption behaviors. The detailed factors are as follows: (1) decrease of surface acidity suppresses NH3 adsorption by strong bonding of alkali to vanadia (major factor); (2) low reducibility prohibits NH3 activation and NO oxidation by formation bonding of alkali to vanadia and ceria (important factor); (3) active NOx(-) species at low temperature diminish because of coverage of alkali on the surfaces (minor factor); and (4) stable, inactive nitrate species at high temperature increase by generating new basic sites (important factor).


Asunto(s)
Ácidos/química , Cerio/química , Potasio/química , Compuestos de Vanadio/química , Adsorción , Catálisis , Óxido Nítrico/análisis , Óxidos de Nitrógeno/química , Oxidación-Reducción , Espectrofotometría Infrarroja , Espectrometría Raman , Propiedades de Superficie , Temperatura
16.
J Nanosci Nanotechnol ; 14(5): 3305-12, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24734545

RESUMEN

Polyamidoamine (PAMAM) dendrimers have been widely used as drug carriers, non-viral gene vectors and imaging agents. However, the use of dendrimers in biological system is constrained because of inherent toxicity and organ accumulation. In this study, the strategy of acetylation and PEGylation-acetylation was used to minimize PAMAM dendrimers toxicities and to improve their biodistribution and pharmacokinetics for medical application. PEGylated-acetylated PAMAM (G4-Ac-PEG) dendrimers were synthesized by PEGylation of acetylated PAMAM dendrimer of generation 4 (G4) with acetic anhydride and polyethylene glycol (PEG) 3.4 k. To investigate the cytotoxicity and in vivo biodistribution of the conjugates, in vitro cell viability analysis, Iodine-125 (125I) imaging, tissue distribution and hematoxylin-eosin (HE) staining were performed. We find that acetylation and PEGylation-acetylation essentially eliminates the inherent dendrimer cytotoxicity in vitro. Planar gamma (gamma) camera imaging revealed that all the conjugates were slowly eliminated from the body, and higher abdominal accumulation of acetylation PAMAM dendrimer was observed. Tissue distribution analysis showed that PEGylated-acetylated dendrimers have longer blood retention and lower accumulation in organs such as the kidney and liver than the non-PEGylated-acetylated dendrimers, but acetylation only can significantly increase the accumulation of G4 in the kidney and decrease the concentration in blood. Histology results reveal that no obvious damage was observed in all groups after high dose administration. This study indicates that PEGylation-acetylation could improve the blood retention, decrease organ accumulation, and improve pharmacokinetic profile, which suggests that PEGylation-acetylation provides an alternative method for PAMAM dendrimers modification.


Asunto(s)
Dendrímeros/síntesis química , Dendrímeros/farmacocinética , Polietilenglicoles/química , Acetilación , Animales , Dendrímeros/administración & dosificación , Células HEK293 , Humanos , Infusiones Intravenosas , Radioisótopos de Yodo/administración & dosificación , Masculino , Ratones , Ratones Endogámicos BALB C , Distribución Tisular
17.
Front Oncol ; 14: 1283991, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38884092

RESUMEN

Objective: To explore the Therapeutic effect of synchronous Integrated intensity modulated radiotherapy combined with chemotherapy in stage IIIc of Cervical Cancer. Methods: A total of 58 patients with stage IIIC cervical cancer (KPS ≥ 80) were analyzed in this study. They were admitted to our hospital between August 2017 and August 2022. Synchronous integrated boost intensity-modulated radiotherapy (SIB-IMRT) and sequential boost intensity-modulated radiotherapy (LCB-IMRT) were used to treat pelvic and/or para-aortic metastatic lymph nodes, with 30 cases in the SIB group and 28 cases in the LCB group. Comparison of short-term and long-term efficacy. Comparison of recurrence and metastasis rates, radiation dose to organs at risk and incidence of adverse drug reactions. Result: 30 patients were treated with simultaneous integrated boost intensity-modulated radiotherapy (SIB-IMRT), and 28 patients were treated with sequential boost intensity-modulated radiotherapy (LCB-IMRT). At the completion of radiotherapy and 3 months after radiotherapy, there was no significant difference in clinical efficacy observed between the two treatment groups. The median overall survival (OS), progression-free survival (PFS), and disease-free survival (DMR) in the SIB-IMRT group were significantly higher compared to the LCB-IMRT group. The SIB-IMRT group demonstrated significantly lower rates compared to the LCB-IMRT group. Furthermore, within 3 years and 5 years, the rates of lymph node recurrence, cervical and vaginal local recurrence, and distant metastasis within the radiotherapy field were significantly lower in the SIB-IMRT group compared to the LCB-IMRT group. There were no significant differences observed between the two groups in terms of the maximum dose to the small intestine (Dmax), dose received by 2cc of the small intestine (D2cc), maximum dose to the rectum (Dmax), and dose received by 1cc of the bladder (D1cc). The incidence of bone marrow toxicity in the SIB-IMRT group was significantly lower compared to the LCB-IMRT group. Moreover, the occurrence of grade III and IV bone marrow toxicity was also significantly lower in the SIB-IMRT group compared to the LCB-IMRT group. Conclusion: The study has concluded that there is no significant differences in in terms of bladder associated adverse events and gastrointestinal toxicity in both Simultaneous Integrated Boost Intensity-Modulated Radiotherapy and Layered Conical Beam Intensity-Modulated Radiation Therapy.

18.
Sci Total Environ ; 916: 170195, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38246364

RESUMEN

Maintaining an optimal eco-environment is important for sustainable regional development. However, existing methods are inadequate for examining both spatial and temporal dimensions. Here, we propose a systematic procedure for spatiotemporal examination of the eco-environment using the space-time cube (STC) model and describe a preliminary investigation of the coupling relationships between basin ecological quality and water eutrophication in upstream of the Han River basin between 2000 and 2020. The STC model considers the temporal dimension as the third dimension in calculations. We first categorized the basin into three sub-watershed types: forest, cultivated land, and artificial surface. Subsequently, the ecological quality and driving factors were assessed and identified using the remote sensing ecological index (RSEI) and Geodetector method, respectively. The findings indicated that the forest basin and artificial surface basin had the highest and lowest ecological quality, respectively. The spatiotemporal cold spots of ecological quality during the past 20 years were mostly located in the vicinity of reservoirs, rivers, and artificial surface areas. Human activity, precipitation, and the percentage of cultivated land were other important driving factors in the artificial surface, forest, and cultivated land sub-watersheds, respectively, in addition to the dominant factors of elevation and temperature. The results also indicated that when the ecological quality degraded to a certain extent, water eutrophication was significantly coupled with the ecological quality of the catchments. The findings of this study are useful for ecological restoration and sustainable river basin development.

19.
Biol Psychiatry ; 95(6): 494-501, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38061463

RESUMEN

The modeling of transcranial magnetic stimulation (TMS)-induced electric fields (E-fields) is a versatile technique for evaluating and refining brain targeting and dosing strategies, while also providing insights into dose-response relationships in the brain. This review outlines the methodologies employed to derive E-field estimations, covering TMS physics, modeling assumptions, and aspects of subject-specific head tissue and coil modeling. We also summarize various numerical methods for solving the E-field and their suitability for various applications. Modeling methodologies have been optimized to efficiently execute numerous TMS simulations across diverse scalp coil configurations, facilitating the identification of optimal setups or rapid cortical E-field visualization for specific brain targets. These brain targets are extrapolated from neurophysiological measurements and neuroimaging, enabling precise and individualized E-field dosing in experimental and clinical applications. This necessitates the quantification of E-field estimates using metrics that enable the comparison of brain target engagement, functional localization, and TMS intensity adjustments across subjects. The integration of E-field modeling with empirical data has the potential to uncover pivotal insights into the aspects of E-fields responsible for stimulating and modulating brain function and states, enhancing behavioral task performance, and impacting the clinical outcomes of personalized TMS interventions.


Asunto(s)
Encéfalo , Estimulación Magnética Transcraneal , Humanos , Estimulación Magnética Transcraneal/métodos , Encéfalo/fisiología , Neuroimagen
20.
AMB Express ; 14(1): 63, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38824272

RESUMEN

Adequate bowel cleansing is crucial for endoscopic diagnosis and treatment, and the recovery of gut microbiota after intestinal cleansing is also important. A hypertonic syrup predominantly comprising L-arabinose and D-xylose (20% xylo-oligosaccharides) can be extracted from the hemicellulose of corn husks and cobs. L-Arabinose and xylo-oligosaccharides have been reported to relieve constipation and improve the gut microbial environment. This study evaluated the bowel cleansing effect of the aforementioned syrup and its influence on the organism and intestinal microbiota after cleansing in comparison with polyethylene glycol-4000 (PEG-4000) in mice. Bowel cleansing was performed using syrup or PEG-4000 in C57BL/6J mice, and the effect of intestinal preparation and its influence on serum electrolytes and gut microbiota after bowel cleansing were evaluated. The volume of intestinal residual feces in the syrup group was significantly lower than that in the PEG-4000 group. Additionally, syrup disturbed serum electrolytes more mildly than PEG-4000. Alpha diversity in the gut microbiota was significantly higher in the syrup group than in the PEG-4000 group on the first day after bowel cleansing. However, no difference in beta diversity was observed between the two groups. Syrup increased the abundance of Bifidobacteria and Christensenella and decreased the abundance of Akkermansia in comparison with PEG-4000 on the first day after bowel cleansing. Thus, this syrup has potential clinical use as a bowel cleansing agent given the above effects, its benefits and safety, and better taste and acceptability.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA