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1.
Cell Biochem Funct ; 42(7): e4118, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39267363

RESUMO

Low back pain significantly impacts individuals' quality of life, with intervertebral disc degeneration (IDD) being a primary contributor to this condition. Currently, IDD treatment primarily focuses on symptom management and does not achieve a definitive cure. The cartilage endplate (CEP), a crucial nutrient-supplying tissue of the intervertebral disc, plays a pivotal role in disc degeneration. This review examines the mechanisms underlying CEP degeneration, summarizing recent advancements in understanding the structure and function of CEP, the involvement of various signaling pathways, and the roles of cartilage endplate stem cells (CESCs) and exosomes (Exos) in this process. The aim of this review is to provide a comprehensive reference for future research on CEP. Despite progress in understanding the role of CEP in IDD, the mechanisms underlying CEP degeneration remain incompletely elucidated. Future research poses significant challenges, necessitating further investigations to elucidate the complexities of CEP.


Assuntos
Cartilagem , Degeneração do Disco Intervertebral , Degeneração do Disco Intervertebral/patologia , Degeneração do Disco Intervertebral/metabolismo , Humanos , Cartilagem/metabolismo , Cartilagem/patologia , Animais , Disco Intervertebral/patologia , Disco Intervertebral/metabolismo , Exossomos/metabolismo , Células-Tronco/metabolismo , Células-Tronco/citologia , Células-Tronco/patologia , Transdução de Sinais
2.
Ren Fail ; 46(1): 2301681, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38391160

RESUMO

BACKGROUND: Xenograft kidney transplantation has been receiving increasing attention. The purpose of this study is to use bibliometric analysis to identify papers in this research field and explore their current status and development trends. METHODS: Using the data in the Web of Science core database from Clarivate Analytics as the object of study, we used 'TS = Kidney OR Renal AND xenotransplantation' as the search term to find all literature from 1980 to 2 November 2022. RESULTS: In total, 1005 articles were included. The United States has the highest number of publications and has made significant contributions in this field. Harvard University was at the forefront of this study. Professor Cooper has published 114 articles in this field. Xenotransplantation has the largest number of relevant articles. Transplantation was the most cited journal. High-frequency keywords illustrated the current state of development and future trends in xenotransplantation. The use of transgenic pigs and the development of coordinated co-stimulatory blockers have greatly facilitated progress in xenotransplantation research. We found that 'co-stimulation blockade', 'xenograft survival', 'pluripotent stem cell', 'translational research', and 'genetic engineering' were likely to be the focus of attention in the coming years. CONCLUSIONS: This study screened global publications related to xenogeneic kidney transplantation; analyzed their literature metrology characteristics; identified the most cited articles in the research field; understood the current situation, hot spots, and trends of global research; and provided future development directions for researchers and practitioners.


Assuntos
Transplante de Rim , Rim , Humanos , Animais , Suínos , Transplante Heterólogo , Rim/cirurgia , Bibliometria , Bases de Dados Factuais
3.
Macromol Rapid Commun ; 44(23): e2300213, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37230735

RESUMO

The dielectronic constant of organic semiconductor materials is directly related to its molecule dipole moment, which can be used to guide the design of high-performance organic photovoltaic materials. Herein, two isomeric small molecule acceptors, ANDT-2F and CNDT-2F, are designed and synthesized by using the electron localization effect of alkoxy in different positions of naphthalene. It is found that the axisymmetric ANDT-2F exhibits a larger dipole moment, which can improve exciton dissociation and charge generation efficiencies due to the strong intramolecular charge transfer effect, resulting in the higher photovoltaic performance of devices. Moreover, PBDB-T:ANDT-2F blend film exhibits larger and more balanced hole and electron mobility as well as nanoscale phase separation due to the favorable miscibility. As a result, the optimized device based on axisymmetric ANDT-2F shows a JSC of 21.30 mA cm-2 , an FF of 66.21%, and a power conversion energy of 12.13%, higher than that of centrosymmetric CNDT-2F-based device. This work provides important implications for designing and synthesizing efficient organic photovoltaic materials by tuning their dipole moment.


Assuntos
Elétrons , Semicondutores , Isomerismo
4.
Eur Spine J ; 32(12): 4246-4258, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37115281

RESUMO

PURPOSE: Tuberculosis is one of the oldest diseases in human history, and spinal tuberculosis (STB) is the most common form of extrapulmonary tuberculosis. A large number of research has been conducted in this field. However, there has been no bibliometric analysis performed in recent years in STB. The aim of this study was to analyze trends and hotspots in research on STB. METHODS: Publications regarding STB between 1980 and 2022 were extracted from the Web of Science database. CiteSpace (V5.7.R2) and VOSviewer (1.6.10) were used to perform global analyses of the number of publications, countries, institutions, authors, journals, keywords, and cited references. RESULTS: A total of 1262 articles were published between 1980 and 2022. We observed rapid growth in the number of publications since 2010. Spine had the highest number of publications (47, 3.7%). Zhang HQ and Wang XY were key researchers. The Central South University published the most papers (90, 7.1%). China was the leading contributor in this field with 459 publications and 29 H-index. National partnerships are dominated by the USA, and there is a lack of active cooperation between other countries and authors. CONCLUSION: research on STB has achieved great progress, with an increasing number of publications since 2010. Surgical treatment and debridement are current research hots pots, and diagnosis, drug resistance, and kyphosis are likely research frontiers. Cooperation between countries and authors needs to be further strengthened.


Assuntos
Tuberculose da Coluna Vertebral , Humanos , Tuberculose da Coluna Vertebral/epidemiologia , Tuberculose da Coluna Vertebral/cirurgia , Coluna Vertebral/cirurgia , Bibliometria , China , Bases de Dados Factuais
5.
Knee Surg Sports Traumatol Arthrosc ; 31(5): 1953-1962, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36515732

RESUMO

PURPOSE: Rotator cuff tendon-bone healing often leads to scarring and low biomechanical strength, resulting in a tendency to re-tear. This study examined whether combining autologous osteochondral transplantation and periosteum transplantation increases fibrocartilage transition zone regeneration and improves biomechanical fixation. METHODS: A total of 48 New Zealand white rabbits were divided into the periosteum, autologous osteochondral, combination of autologous osteochondral and periosteum, and control groups. The supraspinatus tendon was cut from the greater tuberosity and repaired by different transplants. A total of 12 rabbits were used for histological examination (haematoxylin and eosin staining, Masson's staining and Safranin-O staining) at 4, 8 and 12 weeks after the repair, and 36 rabbits were used for biomechanical tests (maximal failure load and stiffness). RESULTS: At 4 weeks following the operation, each group had a large tendon-bone gap with a small number of disordered collagen fibres. At 8 weeks, the tendon-bone gap was smaller than that before the operation, and the tendon-bone gap in each experimental group was smaller with neater and denser collagen fibres and chondrocytes than in the control group, with the osteochondral combined periosteum group having the best results. At 12 weeks, the typical tendon-bone transitional structure was observed in the osteochondral combined periosteum group, and more collagen fibres and chondrocytes were generated in each group. The osteochondral combined periosteum group had the largest staining area and the largest amount of cartilage. The maximum tensile strength and stiffness of each group increased over time. There was no significant difference in each group's maximum tensile strength and stiffness at 4 weeks after the operation. However, the maximum tensile strength and stiffness of the osteochondral combined periosteum group at 8 and 12 weeks after operation were significantly higher than those of other groups (P < 0.05). CONCLUSION: Histological and biomechanical results show that autologous osteochondral transplantation combined with periosteum transplantation can effectively promote the regeneration of fibrous cartilage in the tendon-bone junction of the rotator cuff. It is concluded that this technique is a new treatment method to promote tendon-bone healing in the rotator cuff.


Assuntos
Lesões do Manguito Rotador , Manguito Rotador , Coelhos , Animais , Manguito Rotador/cirurgia , Periósteo , Lesões do Manguito Rotador/cirurgia , Cicatrização , Fenômenos Biomecânicos , Tendões/transplante , Fibrocartilagem , Colágeno
6.
Arch Orthop Trauma Surg ; 143(5): 2653-2663, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36194254

RESUMO

PURPOSE: This systematic review and meta-analysis aimed to evaluate the correlation between increased critical shoulder angle (CSA) and higher retear rates and functional outcomes after arthroscopic rotator cuff repair (ARCR). METHODS: PubMed, Embase, Web of Science, and Cochrane Library databases published before January 2022 were comprehensively searched. Two reviewers independently reviewed the titles and abstracts using the specified criteria. Studies were included if the authors clearly described the correlation between the CSA and rotator cuff repair. Data on patient characteristics, mean CSA, retear rate, and the functional score was pooled from the selected articles. A meta-analysis was performed using Review Manager (RevMan) 5.4.1 software, 2020 (Cochrane Collaboration, Copenhagen, Denmark). RESULTS: Eleven articles involving 1449 patients from 7 countries were included. The ages of the patients ranged from 45 to 75 years. The follow-up period ranged from 6 to 96 months. The mean CSA was greater in the retear group than in the non-retear group after ARCR (mean difference 2.73°; 95% confidence interval [CI] 0.69-4.77) (p = 0.009). Three studies evaluated the association between increased CSA and the postoperative retear rate. All three studies showed a higher postoperative retear rate in patients with an increased CSA (odds ratio 5.35; 95% CI 2.02-14.15; p = 0.0007). No association was found between CSA and Constant-Murley (Constant), the University of California at Los Angeles (UCLA), or Visual Analog Scale (VAS) scores during the follow-up period of 24-96 months (p > 0.05). CONCLUSIONS: This systematic review and meta-analysis showed that CSA correlates highly with rotator cuff retear after ARCR. In addition, the postoperative retear rate of the rotator cuff increased with increased CSA. CSA appeared to not affect worse functional outcomes in patients after ARCR.


Assuntos
Lesões do Manguito Rotador , Articulação do Ombro , Humanos , Pessoa de Meia-Idade , Idoso , Ombro/cirurgia , Manguito Rotador/cirurgia , Lesões do Manguito Rotador/cirurgia , Resultado do Tratamento , Articulação do Ombro/cirurgia , Artroscopia , Imageamento por Ressonância Magnética
7.
Macromol Rapid Commun ; 43(17): e2200177, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35355354

RESUMO

For decades, crude oil spills and oil wastewater have become the most problematic environmental pollution and damage to public health. Therefore, it is considerable to develop superhydrophobic polymer foam for separating oil from water with high selectivity and sorption capacity. Here, a new type of environmentally friendly pure polypropylene (PP) foam with superhydrophobicity is first time proposed with a particular coexistence of microspheres and microporous structure fabricated via an advanced solvent-evaporation method. The PP foam exhibits exceptional superhydrophobic with a water contact angle of 151° and the maximum saturated adsorption capacity of 26 g g-1 . After more than 15 h of cyclic continuous oil-water pumping experiment, it still maintains a high oil absorption efficiency of 98%, providing the basis for practical commercial applications. More importantly, the variation of hydrophobic properties is described by Flory-Huggins polymer solution theory and Huggins interaction parameters, and the optimal solution ratio range is predicted which provides a relevant theoretical basis for actual industrial production.


Assuntos
Poluição por Petróleo , Polipropilenos , Microesferas , Poluição por Petróleo/análise , Polipropilenos/química , Solventes , Água/química
8.
Phys Chem Chem Phys ; 23(22): 12654-12667, 2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-34036985

RESUMO

A multimode Brownian oscillator model is employed to investigate the absorption spectra of pentacene and its derivatives in solution and thin films. Excellent agreement has been obtained between simulated and measured absorption spectra. Furthermore, using parameters obtained from fitting the absorption spectra of these pentacene derivatives, the singlet fission dynamics and two-dimensional electronic spectra of an ab initio Hamiltonian are investigated by Dirac-Frenkel time-dependent variation with multiple Davydov trial states. It is found that the periodic wave packet motion induced in the displaced excited state, and the accompanying vibrational relaxation, can be visualized by two-dimensional electronic spectra at short times.

9.
Chem Soc Rev ; 49(9): 2828-2842, 2020 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-32239058

RESUMO

The study of organic photovoltaics (OPVs) has made great progress in the past decade, mainly attributed to the invention of new active layer materials. Among various types of active layer materials, molecules with A-D-A (acceptor-donor-acceptor) architecture have demonstrated much great success in recent years. Thus, in this review, we will focus on A-D-A molecules used in OPVs from the viewpoint of chemists. Notably, the chemical structure-property relationships of A-D-A molecules will be highlighted and the underlying reasons for their outstanding performance will be discussed. The device stability correlated to A-D-A molecules will also be commented on. Finally, an outlook and challenges for future OPV molecule design and device fabrication to achieve higher performance will be presented.

10.
Zhongguo Dang Dai Er Ke Za Zhi ; 22(3): 231-237, 2020 Mar.
Artigo em Zh | MEDLINE | ID: mdl-32204759

RESUMO

OBJECTIVE: To identify risk factors for minimally invasive surfactant administration (MISA) failure in the treatment of preterm infants with respiratory distress syndrome (RDS) and the influence of MISA failure on neonatal outcome. METHODS: A retrospective analysis was performed for the clinical data of 148 preterm infants with a gestational age of ≤32 weeks and a clinical diagnosis of RDS, who were admitted to the neonatal intensive care unit of eight tertiary hospitals in Beijing, Tianjin and Hebei Province from July 1, 2017 to December 31, 2018 and were treated with MISA (bovine pulmonary surfactant, PS). According to whether MISA failure (defined as the need for mechanical ventilation within 72 hours after MISA) was observed, the infants were divided into two groups: MISA failure group (n=16) and MISA success (n=132). A logistic regression analysis was used to investigate the risk factors for MISA failure and its influence on neonatal outcome. RESULTS: The MISA failure rate was 10.8% (16/148). The logistic regression analysis showed that a high incidence rate of grade >II RDS before PS administration, low mean arterial pressure and high pulse pressure before administration, a low dose of initial PS administration, and long injection time and operation time were the risk factors for MISA failure (OR=5.983, 1.210, 1.183, 1.055, 1.036, and 1.058 respectively, P<0.05). After the control for the above risk factors, the logistic regression analysis showed that the MISA failure group had a significantly higher incidence rate of bronchopulmonary dysplasia (BPD) (OR=8.537, P<0.05). CONCLUSIONS: A high grade of RDS, a low mean arterial pressure, and a high pulse pressure before administration are independent risk factors for MISA failure, and a low dose of initial PS administration, a long injection time, and a long operation time may increase the risk of MISA failure. MISA failure may increase the incidence rate of BPD in preterm infants.


Assuntos
Surfactantes Pulmonares/uso terapêutico , Síndrome do Desconforto Respiratório do Recém-Nascido/tratamento farmacológico , Animais , Displasia Broncopulmonar , Bovinos , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Respiração Artificial , Estudos Retrospectivos , Fatores de Risco , Tensoativos
11.
Opt Lett ; 43(8): 1722-1725, 2018 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-29652349

RESUMO

We propose and experimentally demonstrate a chaotic Brillouin optical correlation-domain analysis system for distributed fiber sensing. The utilization of a chaotic laser with a low coherence state ensures high spatial resolution. The experimental results demonstrate a 4 cm spatial resolution over a 906 m measurement range. The uncertainty in the measurement of the local Brillouin frequency shift is ±1.2 MHz. The analysis of the expected spatial resolution and signal-to-noise ratio is also given.

12.
Angew Chem Int Ed Engl ; 57(41): 13555-13559, 2018 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-30144255

RESUMO

Success in obtaining higher-order twistarenes with precise structures is very important for fundamentally understanding the relationship between the structures and physical properties/optoelectronic applications. In this research, by using the advantages from a retro-Diels-Alder process (clean reaction) and the cross-conjugated nature of the pyrene unit, a novel dodeca-twistarene was prepared for the first time. Its structure, confirmed by single-crystal XRD analysis, indicates that it possesses a twisted angle (≈30°), and two neighboring molecules in the crystal lattice are perpendicular to each other because of the twisted character and the strong intermolecular CH-π interactions. However, its basic physicochemical properties suggest its instability in air derives from its elevated HOMO energy level, although NICS calculations confirm that the pyrene units contribution poorly to the π conjugation of the overall molecule.

13.
Mol Pharm ; 13(11): 3964-3975, 2016 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-27653759

RESUMO

It has been technically challenging to specify the detailed molecular interactions and binding motif between drugs and polymeric inhibitors in the solid state. To further investigate drug-polymer interactions from a molecular perspective, a solid dispersion of clofazimine (CLF) and hypromellose phthalate (HPMCP), with reported superior amorphous drug loading capacity and physical stability, was selected as a model system. The CLF-HPMCP interactions in solid dispersions were investigated by various solid state spectroscopic methods including ultraviolet-visible (UV-vis), infrared (IR), and solid-state NMR (ssNMR) spectroscopy. Significant spectral changes suggest that protonated CLF is ionically bonded to the carboxylate from the phthalyl substituents of HPMCP. In addition, multivariate analysis of spectra was applied to optimize the concentration of polymeric inhibitor used to formulate the amorphous solid dispersions. Most interestingly, proton transfer between CLF and carboxylic acid was experimentally investigated from 2D 1H-1H homonuclear double quantum NMR spectra by utilizing the ultrafast magic-angle spinning (MAS) technique. The molecular interaction pattern and the critical bonding structure in CLF-HPMCP dispersions were further delineated by successfully correlating ssNMR findings with quantum chemistry calculations. These high-resolution investigations provide critical structural information on active pharmaceutical ingredient-polymer interaction, which can be useful for rational selection of appropriate polymeric carriers, which are effective crystallization inhibitors for amorphous drugs.


Assuntos
Clofazimina/química , Metilcelulose/análogos & derivados , Espectroscopia de Ressonância Magnética , Metilcelulose/química , Estrutura Molecular , Polímeros/química , Análise de Componente Principal , Espectrofotometria Infravermelho
14.
Phys Chem Chem Phys ; 18(4): 3173-8, 2016 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-26743159

RESUMO

Recent research progress in black phosphorus sheets strongly encourages us to employ pentacene as a parent system to systematically investigate how the "doping" of sp(2)-phosphorus atoms onto the backbone of pentacene influences its optical and charge transport properties. Our theoretical investigations proved that increasing the contribution of the pz atomic orbital of the sp(2)-phosphorus to the frontier molecular orbital of phosphapentacenes could significantly decrease both hole and electron reorganization energies and dramatically red-shift the absorption of pentacene. The record smallest hole and electron reorganization energies of 69.80 and 95.74 meV for heteropentacene derivatives were obtained. These results suggest that phosphapentacenes (or phosphaacenes) could be potential promising candidates to achieve both higher and balanced mobilities in organic field effect transistors and realize a better power conversion efficiency in organic photovoltaics.

15.
Clin Exp Hypertens ; 38(1): 63-70, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26305278

RESUMO

OBJECTIVE: To assess the synergistic effects of gene polymorphisms of the renin-angiotensin-aldosterone system (RAAS) on essential hypertension (EH) in Kazakhs in Xinjiang. METHODS: A cross-sectional case-control association study was conducted in 52 1 hypertensive and 623 normotensive subjects of Kazakh ethnicity on eight common single nucleotide polymorphisms (SNPs) interspersed over five genes of the RAAS. SNPs were genotyped by polymerase chain reaction-restriction fragment length polymorphism. Interactions among the SNPs were analyzed by the multifactor dimensionality reduction method (MDR). RESULTS: In single-locus analysis, subjects with AGT -6G, ACE D, and CYP11B2 -344C had increased susceptibility to EH (OR: 1.249; 1.425; 1.201). When subgrouped by sex, males with the t allele of REN Taq I had decreased risk for EH (OR: 0.529), and those with AGT -6G and CYP11B2 -344 C had increased risk for EH (OR: 1.498; 1.449). In females, carrying ACE D increased the risk for EH. (OR: 1.327). In six AGT haplotypes, H1 was protective, while H3 increased susceptibility to EH (OR: 0.683; 2.025). Interaction analysis by MDR showed that there was a strong synergistic effect between ACE I/D and CY11B2 (T-344C) and a moderate interaction between both ACE I/D and CY11B2 T-344C and AGT A-6G. CONCLUSIONS: There was a strong synergistic effect between ACE I/D and CY11B2 T-344C and a moderate effect between both ACE I/D and CY11B2 T-344C and AGT A-6G. AGT -6G, ACE D, and CY11B2 -344C increased susceptibility to EH. REN Taq I, AGT -6G, CY11B2 -344 C and ACE D were associated with male and female EH, respectively. H1 and H3 of AGT were protective and risk haplotypes, respectively.


Assuntos
Angiotensinogênio/genética , Pressão Sanguínea/genética , Citocromo P-450 CYP11B2/genética , Hipertensão , Peptidil Dipeptidase A/genética , Adulto , Alelos , China/epidemiologia , Estudos Transversais , Hipertensão Essencial , Etnicidade/genética , Feminino , Predisposição Genética para Doença/etnologia , Haplótipos , Humanos , Hipertensão/diagnóstico , Hipertensão/etnologia , Hipertensão/genética , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Fatores de Proteção , Sistema Renina-Angiotensina/genética
16.
J Am Chem Soc ; 137(11): 3886-93, 2015 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-25736989

RESUMO

A series of acceptor-donor-acceptor simple oligomer-like small molecules based on oligothiophenes, namely, DRCN4T-DRCN9T, were designed and synthesized. Their optical, electrical, and thermal properties and photovoltaic performances were systematically investigated. Except for DRCN4T, excellent performances were obtained for DRCN5T-DRCN9T. The devices based on DRCN5T, DRCN7T, and DRCN9T with axisymmetric chemical structures exhibit much higher short-circuit current densities than those based on DRCN6T and DRCN8T with centrosymmetric chemical structures, which is attributed to their well-developed fibrillar network with a feature size less than 20 nm. The devices based on DRCN5T/PC71BM showed a notable certified power conversion efficiency (PCE) of 10.10% under AM 1.5G irradiation (100 mW cm(-2)) using a simple solution spin-coating fabrication process. This is the highest PCE for single-junction small-molecule-based organic photovoltaics (OPVs) reported to date. DRCN5T is a rather simpler molecule compared with all of the other high-performance molecules in OPVs to date, and this might highlight its advantage in the future possible commercialization of OPVs. These results demonstrate that a fine and balanced modification/design of chemical structure can make significant performance differences and that the performance of solution-processed small-molecule-based solar cells can be comparable to or even surpass that of their polymer counterparts.

17.
Mol Pharm ; 12(7): 2459-68, 2015 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-25988812

RESUMO

Strong associations between drug and polymeric carriers are expected to contribute to higher drug loading capacities and better physical stability of amorphous solid dispersions. However, molecular details of the interaction patterns and underlying mechanisms are still unclear. In the present study, a series of amorphous solid dispersions of clofazimine (CLF), an antileprosy drug, were prepared with different polymers by applying the solvent evaporation method. When using hypromellose phthalate (HPMCP) as the carrier, the amorphous solid dispersion system exhibits not only superior drug loading capacity (63% w/w) but also color change due to strong drug-polymer association. In order to further explain these experimental observations, the interaction between CLF and HPMCP was investigated in a nonpolar volatile solvent system (chloroform) prior to forming the solid dispersion. We observed significant UV/vis and (1)H NMR spectral changes suggesting the protonation of CLF and formation of ion pairs between CLF and HPMCP in chloroform. Furthermore, nuclear Overhauser effect spectroscopy (NOESY) and diffusion order spectroscopy (DOSY) were employed to evaluate the strength of associations between drug and polymers, as well as the molecular mobility of CLF. Finally, by correlating the experimental values with quantum chemistry calculations, we demonstrate that the protonated CLF is binding to the carboxylate group of HPMCP as an ion pair and propose a possible structural model of the drug-polymer complex. Understanding the drug and carrier interaction patterns from a molecular perspective is critical for the rational design of new amorphous solid dispersions.


Assuntos
Clofazimina/química , Polímeros/química , Química Farmacêutica/métodos , Portadores de Fármacos/química , Composição de Medicamentos/métodos , Estabilidade de Medicamentos , Hansenostáticos/química , Metilcelulose/análogos & derivados , Metilcelulose/química , Solubilidade , Solventes/química
18.
Clin Exp Hypertens ; : 1-8, 2015 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-26269000

RESUMO

OBJECTIVE: To assess the synergistic effects of gene polymorphisms of the renin-angiotensin-aldosterone system (RAAS) on essential hypertension (EH) in Kazakhs in Xinjiang. METHODS: A cross-sectional case-control association study was conducted in 52 1 hypertensive and 623 normotensive subjects of Kazakh ethnicity on eight common single nucleotide polymorphisms (SNPs) interspersed over five genes of the RAAS. SNPs were genotyped by polymerase chain reaction-restriction fragment length polymorphism. Interactions among the SNPs were analyzed by the multifactor dimensionality reduction method (MDR). RESULTS: In single-locus analysis, subjects with AGT -6G, ACE D, and CYP11B2 -344C had increased susceptibility to EH (OR: 1.249; 1.425; 1.201). When subgrouped by sex, males with the t allele of REN Taq I had decreased risk for EH (OR: 0.529), and those with AGT -6G and CYP11B2 -344 C had increased risk for EH (OR: 1.498; 1.449). In females, carrying ACE D increased the risk for EH. (OR: 1.327). In six AGT haplotypes, H1 was protective, while H3 increased susceptibility to EH (OR: 0.683; 2.025). Interaction analysis by MDR showed that there was a strong synergistic effect between ACE I/D and CY11B2 (T-344C) and a moderate interaction between both ACE I/D and CY11B2 T-344C and AGT A-6G. CONCLUSIONS: There was a strong synergistic effect between ACE I/D and CY11B2 T-344C and a moderate effect between both ACE I/D and CY11B2 T-344C and AGT A-6G. AGT -6G, ACE D, and CY11B2 -344C increased susceptibility to EH. REN Taq I, AGT -6G, CY11B2 -344 C and ACE D were associated with male and female EH, respectively. H1 and H3 of AGT were protective and risk haplotypes, respectively.

19.
Zhongguo Dang Dai Er Ke Za Zhi ; 17(5): 464-8, 2015 May.
Artigo em Zh | MEDLINE | ID: mdl-26014696

RESUMO

OBJECTIVE: To study the characteristics of R bone age, C bone age, and T bone age in children with different causes of short stature based on the Tanner and Whitehouse skeletal age assessment system 2 (TW2), and to provide a reference for the etiological diagnosis of short stature. METHODS: Three hundred and sixty-three children with previously untreated short stature were classified into four groups according to the causes: growth hormone deficiency (GHD; 27 cases), idiopathic short stature (ISS; 280 cases), small for gestational age (SGA; 41 cases), and Turner syndrome (TS; 15 cases). The X-ray films of their left hand-wrist bones were taken to determine the bone age. R bone age, C bone age, and T bone age were assessed by the TW2 method and compared with their chronological age (CA). RESULTS: R bone age, C bone age, and T bone age were over 2 years less than CA in both boys and girls from the GHD group. In the ISS group, R bone age, C bone age, and T bone age were about 1 year less than CA in boys, while there were no significant differences between the bone ages and CA in girls. In the SGA group, there were no significant differences between the bone ages and CA in either boys or girls. In the TS group, R bone age and T bone age were significantly lower than CA, while there was no significant difference between C bone age and CA. CONCLUSIONS: The children with different causes of short stature have different characteristics of R bone age, C bone age, and T bone age assessed by the TW2 method. The assessment of R bone age, C bone age, and T bone age by the TW2 method is helpful for the etiological diagnosis of short stature in children.


Assuntos
Determinação da Idade pelo Esqueleto , Estatura , Transtornos do Crescimento/diagnóstico , Adolescente , Criança , Feminino , Transtornos do Crescimento/etiologia , Humanos , Masculino
20.
J Org Chem ; 79(19): 9355-64, 2014 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-25222376

RESUMO

Knölker's iron complex is a "green" catalyst that exhibits low toxicity and is abundant in nature. Density functional theory (DFT) was used to explore the highly chemoselective nature of the catalytic hydrogenation of CH2═CHCH2CHO. An outer-sphere concerted hydrogen transfer was found to be the most reasonable kinetic route for the hydrogenation of the olefin. However, the C═C hydrogenation reaction has a high free energy barrier of 28.1 kcal/mol, requiring a high temperature to overcome. By comparison, the CH═O bond concerted hydrogen-transfer reaction catalyzed using Knölker's iron catalyst has an energy barrier of only 14.0 kcal/mol. Therefore, only the CH═O of CH2═CHCH2CHO can be hydrogenated in the presence of Knölker's catalyst at room temperature, due to kinetic domination. All computational results were in good agreement with experimental results.

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