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1.
Diabetes Obes Metab ; 26(8): 3176-3190, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38738340

RESUMEN

AIM: To investigate the most matchable price of tirzepatide (TIRZ) compared with semaglutide (SEMA) in the treatment of type 2 diabetes in China. METHODS: The patient cohort and clinical efficacy data were derived from the SURPASS-2 trial. Cost-utility analysis and a binary search were performed to identify the most matchable price of TIRZ from a Chinese healthcare provider's perspective. RESULTS: After lifetime simulation, the quality-adjusted life years of TIRZ 5, 10, 15 mg and SEMA 1 mg were 11.17, 11.21, 11.27 and 11.12 years, respectively. Despite an initial assumption that the annual cost of TIRZ equals that of SEMA, our analysis revealed that TIRZ is probably more cost-effective than SEMA. A thorough evaluation of pricing showed that the cost ranges for TIRZ at doses of 5, 10 and 15 mg were $1628.61-$1846.23, $1738.40-$2140.95 and $1800.30-$2430.81, respectively. After adjustment in the univariate sensitivity analysis, the cost ranges for TIRZ 5, 10 and 15 mg were $1542.68-$1757.57, $1573.00-$1967.16 and $1576.54-$2133.96, respectively. These cost intervals were validated through robust probabilistic sensitivity analysis and scenario analysis, except for the cost range for TIRZ 5 mg. CONCLUSIONS: This study shows that, using SEMA as a reference, the annual costs for TIRZ 10 and 15 mg are $1573.00-$1967.16 and $1576.54-$2133.96, respectively, for patients with type 2 diabetes in China.


Asunto(s)
Análisis Costo-Beneficio , Diabetes Mellitus Tipo 2 , Costos de los Medicamentos , Péptidos Similares al Glucagón , Hipoglucemiantes , Años de Vida Ajustados por Calidad de Vida , Humanos , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/economía , Péptidos Similares al Glucagón/uso terapéutico , Péptidos Similares al Glucagón/economía , China , Hipoglucemiantes/economía , Hipoglucemiantes/uso terapéutico , Costos de los Medicamentos/estadística & datos numéricos , Masculino , Femenino , Persona de Mediana Edad , Receptor del Péptido 2 Similar al Glucagón , Polipéptido Inhibidor Gástrico
2.
Int J Biometeorol ; 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38802581

RESUMEN

This study used the time series data of Ganzhou city to explore the individual and interaction effects of temperature and humidity on COPD death, and identify vulnerable subgroups of the population. We collected daily COPD mortality and meteorological data in Ganzhou from 2016 to 2019. The nonlinear distribution lag model was used to examine the associations and interaction between daily mean temperature and humidity and COPD mortality. For the total population, male and 65 years old or above, the relative risk (RR) for COPD mortality could be significant at extremely low temperature (3.3 ℃), reaching 1.799 (95% confidence interval [CI]: 1.216, 2.662), 1.894 (95% CI: 1.164, 3.084) and 1.779 (95% CI:1.185, 2.670). Also, at extremely low humidity (47.8%), the risk reached 1.888 (95% CI: 1.217, 2.930), 1.837 (95% CI: 1.066, 3.165) and 2.166 (95% CI: 1.375, 3.414). The cumulative COPD death risk for females was 3.524 (95% CI: 1.340, 9.267) at high temperature (30.7 ℃), 1.953(95% CI: 1.036, 3.683) at low humidity (47.8%) and 1.726 (95% CI: 1.048, 2.845) at high humidity (96.7%). For the total COPD deaths and subgroups, the interaction effects between daily temperature and humidity were not significant (p > 0.05). Both extremely low temperature and low humidity increased the risk of COPD death in Ganzhou city, especially for males and people over 65 years old. Females were more sensitive to extremely high temperature and humidity. Patients with COPD should pay attention to self-protection under extreme temperature and humidity weather conditions.

3.
Nano Lett ; 23(10): 4290-4297, 2023 05 24.
Artículo en Inglés | MEDLINE | ID: mdl-37141413

RESUMEN

Supramolecular structures of matrix proteins in mineralizing tissues are known to direct the crystallization of inorganic materials. Here we demonstrate how such structures can be synthetically directed into predetermined patterns for which functionality is maintained. The study employs block copolymer lamellar patterns with alternating hydrophilic and hydrophobic regions to direct the assembly of amelogenin-derived peptide nanoribbons that template calcium phosphate nucleation by creating a low-energy interface. Results show that the patterned nanoribbons retain their ß-sheet structure and function and direct the formation of filamentous and plate-shaped calcium phosphate with high fidelity, where the phase, amorphous or crystalline, depends on the choice of mineral precursor and the fidelity depends on peptide sequence. The common ability of supramolecular systems to assemble on surfaces with appropriate chemistry combined with the tendency of many templates to mineralize multiple inorganic materials implies this approach defines a general platform for bottom-up-patterning of hybrid organic-inorganic materials.


Asunto(s)
Biomimética , Nanotubos de Carbono , Polímeros/química , Minerales , Fosfatos de Calcio/química , Péptidos/química
4.
Diabetes Obes Metab ; 25(2): 387-397, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36193880

RESUMEN

INTRODUCTION: The main research purpose is to compare the long-term cost-effectiveness of semaglutide (SEMA) with that of dulaglutide (DULA) for patients with inadequately controlled type 2 diabetes throughout their lifetime. If necessary, the second aim is to investigate a further price cut for SEMA to provide sound advice for government drug price adjustments. METHODS: Cost-utility analysis was performed by the United Kingdom Prospective Diabetes Study Outcomes Model 2 (UKPDS OM2) from the perspective of health care providers in China. Baseline characteristics and clinical efficacy of SEMA and DULA were sourced from the high-dose comparison in the SUSTAIN-7 trial. A binary search was used to identify the scope for further reduction in the price of SEMA. The impact of individual parameters was assessed with sensitivity analyses. RESULTS: Main analysis (SEMA vs. DULA) revealed a mean difference in quality-adjusted life years (QALYs) of 0.04 QALYs and costs of $1132.29. The incremental cost-utility ratio was $26 957.44/QALY, showing that SEMA was a better option compared with DULA. In sensitivity analyses, the discount rate made the greatest contribution to the incremental cost-utility ratio. In the binary search, there was still scope to reduce the SEMA cost further by approximately 6.83% to be cost-effective, taking DULA as a reference. CONCLUSION: After its addition to the National Medical Insurance System in China, SEMA is expected to be a cost-effective choice compared with DULA for patients with type 2 diabetes with inadequately controlled from the cost-utility analysis. However, there is still scope to reduce the annual cost of SEMA further.


Asunto(s)
Diabetes Mellitus Tipo 2 , Seguro , Humanos , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Análisis Costo-Beneficio , Hipoglucemiantes/uso terapéutico , Estudios Prospectivos , Años de Vida Ajustados por Calidad de Vida
5.
Int J Biometeorol ; 67(1): 47-54, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36222915

RESUMEN

Urolithiasis was a global disease and it was more common in southern China. This study looked into the association between daily temperature and urolithiasis hospital admissions in Ganzhou, a large prefecture-level city in southern China. In Ganzhou City from 2016 to 2019, a total of 60,881 hospitalized cases for urolithiasis from 69 hospitals and meteorological data were gathered. The effect of high ambient temperature on urolithiasis hospital admissions was estimated using a distributed lag nonlinear model. Stratified analysis was done to examine sex differences. The study found that in Ganzhou of China, the exposure-response curves approximated a "J" shape which across genders were basically similar. The maximum lag effect occurred on the second day after high temperatures for males but on the third day for females. Compared to the 10 °C reference temperature and considering the cumulative lag effect of 10 days, the relative risks of the daily mean temperature at the 95th percentile on the total, male, and female hospital admissions for urolithiasis were 2.026 (95% CI: 1.628, 2.521), 2.041 (95% CI: 1.603, 2.598), and 2.030 (95% CI: 1.552, 2.655), respectively, but the relative risks between sex were not statistically significant (p = 0.977). Urolithiasis morbidity risk in China could be exacerbated by high temperatures. The effect of high temperature on urolithiasis was similar across genders.


Asunto(s)
Hospitalización , Urolitiasis , Femenino , Masculino , Humanos , Temperatura , China/epidemiología , Urolitiasis/epidemiología , Hospitales
6.
J Am Chem Soc ; 144(26): 11638-11645, 2022 07 06.
Artículo en Inglés | MEDLINE | ID: mdl-35735940

RESUMEN

The molecules at the surface of a liquid have different organization and dynamics from those in the bulk, potentially altering the rate of crystal nucleation and polymorphic selection, but this effect remains poorly understood. Here we demonstrate that nucleation at the surface of a pure liquid, d-arabitol, is vastly enhanced, by 12 orders of magnitude, and selects a different polymorph. The surface effect intensifies with cooling and can be inhibited by a dilute, surface-active second component. This phenomenon arises from the anisotropic molecular packing at the interface and its similarity to the surface-nucleating polymorph. Our finding is relevant for controlling the crystallization and polymorphism in any system with a significant interface such as nanodroplets and atmospheric water.


Asunto(s)
Cristalización , Anisotropía , Transición de Fase
7.
J Chem Phys ; 156(14): 144504, 2022 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-35428390

RESUMEN

Crystal nucleation rates have been measured in the supercooled melts of two richly polymorphic glass-forming liquids: ROY and nifedipine (NIF). ROY or 5-methyl-2-[(2-nitrophenyl)amino]-3-thiophenecarbonitrile is known for its crystals of red, orange, and yellow colors and many polymorphs of solved structures (12). Of the many polymorphs, ON (orange needles) nucleates the fastest with the runner up (Y04) trailing by a factor of 103 when compared under the same mobility-limited condition, while the other unobserved polymorphs are slower yet by at least 5 orders of magnitude. Similarly, of the six polymorphs of NIF, γ' nucleates the fastest, ß' is slower by a factor of 10, and the rest are slower yet by at least 5 decades. In both systems, the faster-nucleating polymorphs are not built from the lowest-energy conformers, while they tend to have higher energies and lower densities and thus greater similarity to the liquid phase by these measures. The temperature ranges of this study covered the glass transition temperature Tg of each system, and we find no evidence that the nucleation rate is sensitive to the passage of Tg. At the lowest temperatures investigated, the rates of nucleation and growth are proportional to each other, indicating that a similar kinetic barrier controls both processes. The classical nucleation theory provides an accurate description of the observed nucleation rates if the crystal growth rate is used to describe the kinetic barrier for nucleation. The quantitative rates of both nucleation and growth for the competing polymorphs enable prediction of the overall rate of crystallization and its polymorphic outcome.


Asunto(s)
Vidrio , Nifedipino , Cristalización , Vidrio/química , Nifedipino/química , Temperatura , Temperatura de Transición
8.
J Biopharm Stat ; 30(2): 322-333, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31693441

RESUMEN

In early phase clinical trial, finding maximum-tolerated dose (MTD) is a very important goal. Many researches show that finding a correct MTD can improve drug efficacy and safety significantly. Usually, dose-finding trials start from very low doses, so in many cases, more than 50% patients or cohorts do not have dose-limiting toxicity (DLT), but DLT may occur suddenly and increase fast along with just two or three doses. Although some fantastic models were built to find MTD, little consideration was given to those '0 DLTs' and the 'jump' of DLTs. In this paper, we developed a Bayesian zero-inflated binomial regression for dose-finding study, which analyses dose-finding data from two aspects: 1) observation of only zeros, 2) number of DLTs based on binomial distribution, so it can help us analyse if the cohorts without DLT have potential possibility to have DLT and fit the 'jump' of DLTs.


Asunto(s)
Algoritmos , Simulación por Computador/estadística & datos numéricos , Dosis Máxima Tolerada , Modelos Estadísticos , Teorema de Bayes , Estudios de Cohortes , Relación Dosis-Respuesta a Droga , Humanos
9.
Pharmacology ; 105(9-10): 598-608, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32008007

RESUMEN

BACKGROUND: Although Platycodin D (PLD) is the main active saponin of Platycodon grandiflorum (PG) and responsible for multiple therapeutic benefits, including antioxidant and antiaging, only few direct demonstrations have been reported on the role of PLD in antiaging process. The present investigation was carried out to elucidate the protection of PLD against aging in vitro and associated molecular mechanisms on H2O2-induced premature senescence model in human -fetal lung diploid fibroblasts 2BS cells. METHODS: The cellular morphology, cell cycle, and senescence-associated ß-galactosidase activity assays were used for senescence-like phenotypes determination in the oxidant challenged model. The oxygen-free radicals reactive oxygen species (ROS), 4-hydroxynonenal (4-HNE), and malondialdehyde (MDA) determinations were estimated by enzyme-linked immunosorbent assay assay. The potential of the mitochondria mass and the mitochondrial membrane were used to observe the alteration of mitochondria. Western blot analysis was performed to determine the protein expression. RESULTS: The results showed that PLD significantly reversed senescence-like phenotypes in the oxidant challenged model, as well as related molecules expression such as p53, p21, and p16. Moreover, PLD treatment significantly decreased the levels of ROS, 4-HNE, and MDA in H2O2-treated 2BS cells. The mechanisms responsible for the antioxidant and antiaging effects of PLD were investigated, we found that mitochondria under PLD conditions show increase membrane potential ratio and stimulate the proliferation of mitochondria mass. In addition, the protein expression of peroxisome proliferator activated receptor gamma coactivator 1α and its downstream targets, that is, nuclear respiratory factor and mitochondrial transcription factor A were also increased in mitochondrial biogenesis. CONCLUSION: These results indicated that PLD prevented H2O2-induced premature senescence in vitro by improving mitochondrial biogenesis to attenuate age-dependent endogenous oxidative damage. Key Message: The study revealed the antioxidant and antiaging potential of PLD against H2O2-induced premature senescence.


Asunto(s)
Antioxidantes/farmacología , Senescencia Celular/efectos de los fármacos , Fibroblastos/efectos de los fármacos , Mitocondrias/efectos de los fármacos , Biogénesis de Organelos , Sustancias Protectoras/farmacología , Saponinas/farmacología , Triterpenos/farmacología , Ciclo Celular/efectos de los fármacos , Proteínas de Unión al ADN/metabolismo , Fibroblastos/metabolismo , Humanos , Peróxido de Hidrógeno/farmacología , Peroxidación de Lípido/efectos de los fármacos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Mitocondrias/metabolismo , Proteínas Mitocondriales/metabolismo , Factores Nucleares de Respiración/metabolismo , Estrés Oxidativo/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Factores de Transcripción/metabolismo
10.
Phys Rev Lett ; 122(2): 026101, 2019 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-30720324

RESUMEN

Material properties depend sensitively on the atomic arrangements and atomic bonding, but these are notoriously difficult to measure in nanosized atomic clusters due to the small size of the objects and the challenge of obtaining bulk samples of identical clusters. Here, we have combined the recent ability to make gram quantities of identical semiconductor quantum-dot nanoparticles with the ability to measure lattice dynamics on small sample quantities of hydrogenated materials using high energy resolution inelastic x-ray scattering, to measure the size dependence of the phonon density of states in CdSe quantum dots. The fact that we have atomically precise structural models for these nanoparticles allows the calculation of the phonon density of states using density functional theory, providing both experimental and theoretical confirmations of the important role that the inertia of the surface capping species plays on determining the lattice dynamics.

11.
Mol Pharm ; 16(11): 4751-4754, 2019 11 04.
Artículo en Inglés | MEDLINE | ID: mdl-31553871

RESUMEN

Amorphous solid dispersions (ASDs) are new formulations currently being used in pharmaceutical industry. The ASDs, in which amorphous drug and polymeric excipients are intimately mixed at the molecular level, exhibit dramatically enhanced solubility and dissolution characteristics relative to their crystalline drug counterparts. In the process of achieving an ever-increasing drug loading (DL), it is noticed, however, that the drug release profile deteriorates significantly beyond a certain DL. As an example, a ritonavir-copovidone ASD achieves continuous and full drug release when DL ≤ 25 wt %. The release drops at 30 wt % and when DL ≥ 35 wt % there is virtually no drug release, behaving like a pure amorphous drug. In this Communication, the phase miscibility of ASD thin films has been investigated by in situ synchrotron X-ray fluorescence (XRF) imaging to elucidate the mechanism for the unique change in the extent of drug release as a function of DL. It is found that the drug release profile correlates well with the amorphous-amorphous phase separation (AAPS) onset. At a lower drug loading (up to 20 wt %), it takes more than 12 h for AAPS to happen while in sharp contrast, it only needs less than 10 min for DL ≥ 32.5 wt %. During AAPS, amorphous drug accumulates on the surface of the film, which prevents further dissolution from the interior of the ASD. The current study provides a mechanistic understanding of the confounding drug release profile of ASDs as a function of DL and opens the door for studying drug-excipient (e.g., polymer, surfactant) interactions via XRF imaging in the future.


Asunto(s)
Polímeros/química , Pirrolidinas/química , Ritonavir/química , Compuestos de Vinilo/química , Cristalización/métodos , Composición de Medicamentos/métodos , Liberación de Fármacos , Excipientes/química , Fluorescencia , Solubilidad , Sincrotrones , Difracción de Rayos X/métodos , Rayos X
13.
J Chem Phys ; 149(5): 054503, 2018 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-30089376

RESUMEN

The rate of crystal nucleation has been measured in four glass-forming molecular liquids: D-sorbitol, D-arabitol, D-xylitol, and glycerol. These polyalcohols have similar rates of crystal growth when compared at the same temperature relative to Tg (the glass transition temperature), peaking near 1.4 Tg, while the nucleation rates J are vastly different. In D-sorbitol and D-arabitol, J reaches a maximum of ∼108 m-3 s-1 near 1.1 Tg, whereas J < 10-2 m-3 s-1 in D-xylitol and <1 m-3 s-1 in glycerol based on no nucleation in large samples after long waits. This confirms the fundamentally different mechanisms for nucleation and growth. Near Tg, both nucleation and growth slow down with a similar temperature dependence, suggesting a similar kinetic barrier for the two processes. This temperature dependence is significantly weaker than that of viscosity η, approximately following η-0.75. This indicates that viscosity is a poor representative of the kinetic barrier for nucleation, and a better choice is the crystal growth rate. Under the latter assumption, the classical nucleation theory (CNT) describes our data reasonably well, yielding σ = 0.013 J/m2 for D-sorbitol and 0.026 J/m2 for D-arabitol, where σ is the critical nucleus/liquid interfacial free energy. There is no strong indication that the CNT fails as the length scale for corporative rearrangement exceeds the size of the critical nucleus, as recently suggested for lithium disilicate.

14.
Pharmacology ; 101(1-2): 104-110, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29136631

RESUMEN

Adverse drug reactions occur frequently and can trigger pseudoallergy, which has become a serious threat to public health. Pseudoallergy is a typical non-immune anaphylactic reaction characterized by the independence of antigen-specific immune responses. In the clinic, pseudoallergy is often elicited by the first dose of medication, and here lies its unpredictability and occasional lethal outcome. However, the mechanisms of pseudoallergy are not well understood. This review focusses on the causes and mechanisms of pseudoallergy induced by drugs. Two categories of mechanisms will be considered, namely, (1) complement activation-related pseudoallergy and (2) mast cell activation-related pseudoallergy. The factors that induce pseudoallergy include opioid drugs, complement activation-related pseudoallergenic drugs, nonsteroidal anti-inflammatory drugs and traditional Chinese medicine injections.


Asunto(s)
Hipersensibilidad a las Drogas/etiología , Activación de Complemento , Hipersensibilidad a las Drogas/inmunología , Humanos
15.
Small ; 13(40)2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28863240

RESUMEN

Silk fibroin (SF) offers great opportunities in manufacturing biocompatible/partially biodegradable devices with environmental benignity and biomedical applications. To obtain active SF devices of next generation, this work is to demonstrate a new functionalization strategy of the mesoscopic functionalization for soft materials. Unlike the atomic functionalization of solid materials, the meso-functionalization is to incorporate meso-dopants, i.e., functional molecules or nanomaterials, quantum dots, into the mesoscopic networks of soft materials. In this work, wool keratin (WK) molecules were adopted as mediating molecules to incorporate gold nanoclusters (AuNCs), into the mesoscopic networks of SF. It follows from our analyses that the ß-crystallites between WK and SF molecules establish the binding between WK@AuNCs and the SF networks. The incorporated WK@AuNCs are electron rich and serve as electronically charged nano particles to bridge the growth of Ag filaments in bio-degradable WK@AuNCs-SF memristors. The meso-functionalization can greatly enhance the performance of SF materials and endows them with new functionalities. This can be highlighted by biocompatible/partly degradable WK@AuNCs functionalized SF resistive random-access memories, having the enhanced resistive switching memory performance, and the unique synapse characteristics and the capability of synapse learning compared with neat SF devices, and of great importance in nonvolatile memory, analog circuits, and neuromorphic applications.


Asunto(s)
Fibroínas/química , Oro/química , Queratinas/química , Nanopartículas del Metal/química , Seda/química
16.
Inorg Chem ; 56(15): 8837-8846, 2017 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-28704045

RESUMEN

The structures of Zr(IV) phosphonate-phosphate based, unconventional metal organic framework materials have been determined using atomic pair distribution function analysis of high energy, X-ray total scattering diffraction data. They are found to form as nanocrystalline layers of Zr phosphate, similar to the bulk, but with a high degree of interlayer disorder and intermediate intralayer order extending around 5 nm. These materials are of interest for their high selectivity for 3+ lanthanide ions. To investigate the mechanism of the selectivity, we utilize difference pair distribution function analysis to extract the local structural environment of Tb3+ ions loaded into the framework. The ions are found to sit between the layers in a manner resembling the local environment of Tb in Scheelite-type terbium phosphate. By mapping this local structure onto that of the refined structure for zirconium-phenyl-phosphonate, we show how dangling oxygens from the phosphate groups, acting like nose hairs, are able to reorient to provide a friendly intercalation environment for the Tb3+ ions.

17.
J Am Chem Soc ; 137(47): 14887-904, 2015 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-26574923

RESUMEN

Electrodeposited manganese oxide films (MnOx) are promising stable oxygen evolution catalysts. They are able to catalyze the oxygen evolution reaction in acidic solutions but with only modest activity when prepared by constant anodic potential deposition. We now show that the performance of these catalysts is improved when they are "activated" by potential cycling protocols, as measured by Tafel analysis (where lower slope is better): upon activation the Tafel slope decreases from ∼120 to ∼70 mV/decade in neutral conditions and from ∼650 to ∼90 mV/decade in acidic solutions. Electrochemical, spectroscopic, and structural methods were employed to study the activation process and support a mechanism where the original birnessite-like MnOx (δ-MnO2) undergoes a phase change, induced by comproportionation with cathodically generated Mn(OH)2, to a hausmannite-like intermediate (α-Mn3O4). Subsequent anodic conditioning from voltage cycling or water oxidation produces a disordered birnessite-like phase, which is highly active for oxygen evolution. At pH 2.5, the current density of activated MnOx (at an overpotential of 600 mV) is 2 orders of magnitude higher than that of the original MnOx and begins to approach that of Ru and Ir oxides in acid.

18.
Prep Biochem Biotechnol ; 45(8): 743-53, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25207990

RESUMEN

Human transferrin receptor, referred as hTfR1, is ubiquitously expressed at low levels in most normal human tissues; however, the expression level of hTfR1 at the blood-brain barrier (BBB) and in tumor tissues is relatively higher. hTfR1 is a type II homodimeric transmembrane protein. The extracellular domain of hTfR1 consists of three domains: helical domain, apical, and protease-like domain. In order to prepare hTfR1 antibody, which can be utilized to deliver drugs across BBB through receptor-mediated endocytosis, we began to express the nonligand binding domain of hTfR1 in Escherichia coli BL21 Transetta (DE3). The TfR1 gene was first obtained from HepG2 cells by reverse-transcription polymerase chain reaction (RT-PCR) and then inserted into pET 32a(c+) vector. The protein was expressed in the form of inclusion body with extremely high purity by the E. coli BL21 Transetta (DE3), and the purity was further improved by size-exclusion chromatography. The Western blot test indicated that the recombinant protein was TfR1 as expected. Above all, this report provided a convenient protocol that could be fulfilled in order to prepare hTfR1 inclusion body, which failed to be purified by an Ni(2+) affinity column.


Asunto(s)
Antígenos CD/aislamiento & purificación , Escherichia coli/química , Cuerpos de Inclusión/química , Receptores de Transferrina/aislamiento & purificación , Antígenos CD/biosíntesis , Antígenos CD/química , Antígenos CD/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Expresión Génica , Humanos , Cuerpos de Inclusión/genética , Cuerpos de Inclusión/metabolismo , Receptores de Transferrina/biosíntesis , Receptores de Transferrina/química , Receptores de Transferrina/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/metabolismo
19.
Phys Rev Lett ; 112(12): 125501, 2014 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-24724657

RESUMEN

The structures of nanocrystalline pristine, potassium hydroxide and sodium acetate intercalated new two-dimensional materials Ti3C2 MXenes were studied using the x-ray atomic pair distribution function technique. Pristine MXene has a hexagonal structure with a=b=3.0505(5) Å, c=19.86(2) Å (S.G. P63/mmc No. 194). Both hydroxyl and fluoride terminating species are present. The intercalation of K+ or Na+ ions expands the Ti3C2 layers perpendicular to the planes but shrinks the in-plane a and b lattice parameters.

20.
Anal Sci ; 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38942981

RESUMEN

Nacre powder, often utilized to counterfeit medicinal pearl powder due to their similar chemical composition and appearance, poses a challenge in product authentication. This study introduces a rapid and efficient method for distinguishing between medicinal pearl powder and nacre powder using X-ray diffraction in conjunction with principal component analysis (PCA). The X-ray diffraction pattern underwent preprocessing techniques including smoothing denoising (Savitzky-Golay filter, 5-point) and second-order derivative analysis. Subsequently, PCA was employed for dimensionality reduction modeling. The CARS method was applied to select optimal variables for model refinement, determining the data preprocessing approach and key modeling variables. This method demonstrates the capability to accurately differentiate between pearl powder, nacre powder, and even counterfeit samples containing up to 90% pearl powder. With a high accuracy rate, swift operational speed, and potential for automation, this approach shows promise for practical implementation in the realm of pearl powder quality control.

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