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1.
Heliyon ; 10(13): e33531, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39040291

RESUMO

Ambidextrous innovation synergy is an effective way for new entrants and R&D entities to break the blockade of key core technologies. This paper constructs a tripartite evolutionary game model of new entrants, the R&D entity, and monopoly enterprises under the monopoly situation of key core technologies, discusses the dynamic equilibrium process of how new entrants cooperate with the R&D entity to carry out the ambidextrous innovation synergy strategy, and extends the model to the policy subsidy situations of different development stages of key core technology. The results show that the monopoly of key core technologies enhances the original innovation search ability of new entrants and promotes the evolution of enterprise imitation innovation to the exploratory innovation strategy. In the basic research stage of key core technology, the exploratory innovation strategy of new entrants is more sensitive to the cost of network embedding and the original innovation knowledge search. New entrants prefer the imitation innovation strategy, and policy subsidies have no significant effect on exploratory innovation. In the promotion stage of the key core technology market, fiscal and tax subsidies can more easily promote the evolution of new entrants from the imitative innovation strategy to the exploratory innovation strategy than R&D subsidies, and network embeddedness can induce enterprises to carry out exploratory innovation only when a certain threshold is reached. In addition, this paper discusses the influence mechanism of monopoly enterprises' suppression intensities and key core technology breakthrough probabilities on the evolution equilibrium of new entrants' ambidextrous innovation synergy strategies.

2.
Proc Natl Acad Sci U S A ; 121(11): e2313123121, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38437546

RESUMO

Organized flaking techniques to obtain predetermined stone tools have been traced back to the early Acheulean (also known as mode 2) in Africa and are seen as indicative of the emergence of advanced technical abilities and in-depth planning skills among early humans. Here, we report one of the earliest known examples of prepared core technology in the archaeological record, at the Cenjiawan (CJW) site in the Nihewan basin of China, dated 1.1 Mya. The operational schemes reconstructed from the CJW refit sets, together with shaping patterns observed in the retouched tools, suggest that Nihewan basin toolmakers had the technical abilities of mode 2 hominins, and developed different survival strategies to adapt to local raw materials and environments. This finding predates the previously earliest known prepared core technology from Eurasia by 0.3 My, and the earliest known mode 2 sites in East Asia by a similar amount of time, thus suggesting that hominins with advanced technologies may have migrated into high latitude East Asia as early as 1.1 Mya.


Assuntos
Hominidae , Tecnologia , Humanos , Animais , Ásia Oriental , China , África
3.
Environ Sci Pollut Res Int ; 31(25): 36474-36491, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38153575

RESUMO

Strengthening the synergistic management of carbon and haze is an important means to realize China's "carbon peaking and carbon neutrality goals" and green development. In this paper, the entropy method is used to measure the key core technology innovation level of 30 provinces in China from 2011 to 2021, and the fixed-effect model is used to empirically test the impact of key core technology innovation on carbon haze synergistic governance and the internal mechanism. The study found that (1) key core technological innovation helps to promote carbon haze synergistic governance. (2) The mechanism test shows that key core technology innovation promotes the synergistic management of carbon haze by improving the clean energy structure. (3) The moderating effect shows that both market incentives and government environmental regulations will strengthen the positive relationship between key core technology innovation and carbon haze synergistic governance. The main contribution of this paper is to reveal the influence mechanism of key core technology innovation on carbon haze synergistic governance, and also to provide theoretical basis for the mechanism and law of carbon haze synergistic governance.


Assuntos
Carbono , China , Poluição do Ar/prevenção & controle , Invenções
4.
J Pharm Biomed Anal ; 233: 115492, 2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37269578

RESUMO

Swellable Core Technology (SCT) tablets, a solid oral dosage formulation designed for the controlled release of Active Pharmaceutical Ingredient (API), are made up of two distinct layers; an active layer containing the active ingredient (10-30%wt) and up to 90%wt polyethylene oxide (PEO); and a sweller layer which contains up to 65%wt PEO. The objective of this study was to develop a process to remove PEO from analytical test solutions and optimize API recovery using physicochemical properties of the API. Quantitation of PEO was performed by liquid chromatography (LC) using an evaporative light scattering detector (ELSD). This was used to build an understanding of removal of PEO using solid-phase extraction and liquid-liquid extraction techniques. A workflow was proposed to allow efficient development of analytical methods for SCT tablets with optimized sample clean-up.


Assuntos
Polietilenoglicóis , Tecnologia , Polietilenoglicóis/química , Comprimidos/química
5.
Zhongguo Yi Liao Qi Xie Za Zhi ; 47(3): 294-297, 2023 May 30.
Artigo em Chinês | MEDLINE | ID: mdl-37288631

RESUMO

Oxygen therapy is an effective clinical method for the treatment of respiratory disorders, oxygen concentrator as a necessary medical auxiliary equipment in hospitals, its research and development has been a hot spot. The study reviewed the development history of the ventilator, introduced the two preparation technique of the oxygen generator pressure swing absorption (PSA) and vacuum pressure swing adsorption (VPSA), and analyzed the core technology development of the oxygen generator. In addition, the study compared some major brands of oxygen concentrators on the market and prospected the development trend of oxygen concentrators.


Assuntos
Oxigenoterapia , Oxigênio , Hospitais , Ventiladores Mecânicos , Desenho de Equipamento
6.
Heliyon ; 9(3): e14553, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37101501

RESUMO

Under the background of digital economy and energy crisis, based on the theory of digital empowerment and prospect theory, aiming at the problems of inefficient collaborative innovation mode, long principal-agent chain, imperfect collaborative innovation mechanism and insufficient digital collaborative innovation degree of the core technology of new energy vehicles, this study constructs a decentralized multi-agent collaborative tripartite evolutionary game model with the participation of government building platform, new energy enterprises and academic research institutions, analyzes the evolution law and key factors, and finally compares the examples of the United States, China and European countries. Results show that: (1) Government subsidies should meet the sum of the strategic income difference and the credibility income is greater than the subsidies to enterprises and research institutions; (2) The subsidy structure and innovation performance show an inverted U-shaped structure. The management mechanism of platform should be optimized; (3) Government should improve the threshold for innovators to enter the decentralized new energy vehicle core technology breakthrough platform, and the contract maintenance strength is conducive; (4) The innovation subject has a dynamic income cost distribution coefficient, and reasonable control of the income and cost sharing coefficient is important; (5) Digital empowerment can make the above four mechanisms achieve dynamic optimization iteration and achieve better equilibrium solutions. Finally, practical countermeasures for the government are put forward, which improves the theoretical research and practical exploration.

7.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-982231

RESUMO

Oxygen therapy is an effective clinical method for the treatment of respiratory disorders, oxygen concentrator as a necessary medical auxiliary equipment in hospitals, its research and development has been a hot spot. The study reviewed the development history of the ventilator, introduced the two preparation technique of the oxygen generator pressure swing absorption (PSA) and vacuum pressure swing adsorption (VPSA), and analyzed the core technology development of the oxygen generator. In addition, the study compared some major brands of oxygen concentrators on the market and prospected the development trend of oxygen concentrators.


Assuntos
Oxigênio , Oxigenoterapia , Hospitais , Ventiladores Mecânicos , Desenho de Equipamento
8.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-995832

RESUMO

Objective:As a newly emerging thing, the construction and operation management of research wards are still being explored. According to the previous practice, this study summarized and shared the key points of a demonstration research ward in Beijing, and provided a reference for the development of domestic research wards.Methods:Focusing on improving the efficiency and quality of clinical research, this article summarizes and shares the experience of research ward construction. In addition, this study explores how to maintain the high-quality sustainable development of research wards from the aspects of improving core competence, system construction, and talent training.Results:Professional teams, innovative operation modes, as well as intelligence and informatization could improve the quality of clinical research. Besides, the improvement of core competence, talent training, and policy support ensure sustainable development of research wards.Conclusions:As clinical research platforms, the development paths of research wards need to be clarified further. The standardized construction and sustainable development of research wards can effectively improve clinical research capability and promote the transformation of scientific achievements.

9.
Acta Radiol ; 63(1): 35-41, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33356359

RESUMO

BACKGROUND: Percutaneous needle biopsy of the lung (PCBL) under image guidance has become a safe and effective minimal invasive method to obtain a specimen related histological diagnosis of pulmonary lesions. PURPOSE: To evaluate the diagnostic yield and safety of two different coaxial biopsy technologies: full core and notch sampling technology. The former allowing the removal of full punch cylinders and the latter using a cutting-edge mechanism. MATERIAL AND METHODS: A retrospective analysis of 48 consecutive PCBL procedures has been carried out for this prognostic study, involving patients with a documented pulmonary nodule or mass lesion on previous computed tomography (CT) scans. The study population included 38 men and 10 women (mean age = 67 years). Of these 48 patients who underwent a procedure with a co-axial cutting system, 24 have been performed with notch sampling technology and 24 with full core technology. RESULTS: Out of the 48 biopsy procedures, 46 yielded specimens were adequate for histopathological evaluation, consistent with a technical success rate of 96%. The most common induced image-guided biopsy complication was a pneumothorax, occurring in 14 patients (35%). Seven patients with a pneumothorax were attributed to the full core technology and seven to the notch sampling technology (odds ratio = 1, 95% confidence interval = 0.28-3.51, P = 1). CONCLUSION: In the setting of full core versus notch sampling percutaneous CT-guided coaxial needle biopsy of the lung, no significant difference in the diagnostic accuracy and the incidence of pneumothoraces could be shown, while both technologies have an excellent diagnostic performance.


Assuntos
Biópsia Guiada por Imagem/métodos , Pneumopatias/patologia , Pneumotórax/etiologia , Tomografia Computadorizada por Raios X , Idoso , Biópsia com Agulha de Grande Calibre/efeitos adversos , Feminino , Humanos , Biópsia Guiada por Imagem/efeitos adversos , Pneumopatias/diagnóstico por imagem , Masculino , Prognóstico , Estudos Retrospectivos
10.
Prensa méd. argent ; Prensa méd. argent;107(2): 97-104, 20210000. fig, tab
Artigo em Inglês | LILACS, BINACIS | ID: biblio-1361373

RESUMO

Objetivos: Evaluar la frecuencia y gravedad de la hemorragia parenquimatosa pulmonar tras la biopsia pulmonar con aguja transtorácica coaxial, según factores de procedimiento, aún no descritos en la literatura. El objetivo de este estudio fue determinar si la elección de la tecnología de biopsia coaxial, el posicionamiento del paciente y la dignidad de la lesión son tres nuevas variables que influyen en el riesgo de hemorragia parenquimatosa tras biopsias coaxiales de pulmón. Métodos: Se revisaron retrospectivamente los registros de 117 pacientes que se sometieron a biopsias con aguja transtorácica del pulmón entre enero de 2018 y abril de 2020. El resultado primario fue la hemorragia pulmonar. Se ha utilizado un sistema de clasificación para clasificar la hemorragia parenquimatosa pulmonar: Grado 0 - Grado 3. Se evaluaron tres variables novedosas relacionadas con el paciente, la técnica y la lesión como predictores de hemorragia pulmonar: tecnología de biopsia coaxial, posición del paciente y dignidad de la lesión. Resultados: De los 117 pacientes, 18 (15,4%) pacientes con tecnología de biopsia coaxial de corte, versus 29 (24,8%) pacientes con tecnología coaxial de núcleo completo mostraron hemorragia significativa en las exploraciones de control posteriores a la biopsia. (IC del 95% 0,06-0,33, p <0,0001). No hubo diferencias significativas en la hemorragia pulmonar entre el diagnóstico histológico benigno y maligno (IC 95% 0,84-4,44, p = 0,1199) y la posición del paciente en decúbito prono o supino (IC 95%: 0,57-2,57, p = 0,6232). Conclusiones: La incidencia y gravedad de la hemorragia pulmonar depende de la tecnología de biopsia coaxial utilizada; siendo mayor en pacientes sometidos a una biopsia con tecnología full-core y menor después del uso de tecnología de corte. En este estudio de pronóstico no se estableció una correlación significativa entre la hemorragia pulmonar parenquimatosa y la posición del paciente o la dignidad de la lesión


Objectives: To evaluate the frequency and severity of pulmonary parenchymal hemorrhage after coaxial transthoracic needle biopsy of the lung, according to procedural factors, not yet described in literature. The aim of this study was to determine whether the choice of the coaxial biopsy technology, patient positioning and the lesion dignity are three new variables influencing the risk of parenchymal hemorrhage after coaxial biopsies of the lung. Methods: Records from 117 patients who underwent transthoracic needle biopsies of the lung between January 2018 and April 2020 have been retrospectively reviewed. The primary outcome was pulmonary hemorrhage. A grading system has been used to classify pulmonary parenchymal hemorrhage: Grade 0 ­ Grade 3. Three novel patient, technique and lesion-related variables were evaluated as predictors of pulmonary hemorrhage: coaxial biopsy technology, patient positioning and lesion dignity. Results: Out of the 117 patients, 18 (15,4%) patients with cutting coaxial biopsy technology, versus 29 (24,8%) patients with full core coaxial technology showed significant hemorrhage on the post-biopsy control scans. (95% CI 0,06-0,33, p<0,0001). No significant difference in pulmonary hemorrhage between benign and malignant histological diagnosis (95% CI 0,84-4,44, p=0,1199) and prone or supine patient positioning (95% CI: 0,57-2,57, p= 0,6232) was found. Conclusions: The incidence and severity of pulmonary hemorrhage depends on the coaxial biopsy technology used; being higher in patients undergoing a biopsy with full-core technology and lower after the use of cutting technology. No significant correlation between parenchymal pulmonary hemorrhage and patient positioning or lesion dignity was established in this prognostic study.


Assuntos
Humanos , Prognóstico , Tomografia Computadorizada por Raios X , Estudos Retrospectivos , Fatores de Risco , Lesão Pulmonar/terapia , Biópsia Guiada por Imagem/métodos , Hemorragia/prevenção & controle , Decúbito Dorsal
11.
Chin Med ; 15: 115, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33133232

RESUMO

The outbreak of COVID-19 has recently evolved into a global pandemic. Up to July 2020, almost every country has confirmed COVID-19 cases reported worldwide. Many leading experts have predicted that the epidemic will persist for relatively a long period of time. Thus far, there have been no remedies proven effective against the disease. As the nation where COVID-19 broke out first, China has adopted a combination of traditional Chinese medicine and western medicine to fight against the disease, and has achieved significant clinical result. Up to now, the COVID-19 pandemic has been effectively controlled in China. However, the rest of the world (except for a limited number of countries and regions) is still in deep water. This paper thoroughly summarizes interdisciplinary notions and techniques, including disease model, biochip, network pharmacology, and molecular docking technology, etc., providing a reference for researchers in the screening of drugs for COVID-19 prevention and treatment. These methodologies may facilitate researchers to screen out more potential drugs for treating COVID-19 pneumonia and to tackle this global crisis.

12.
Innovation (Camb) ; 1(1): 100015, 2020 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-34557703

RESUMO

The Universe is a complicated network that evolved out of the Big Bang to the human-dominated world we see today. Technology is a collection of natural or scientific phenomena that have been discovered and used by human beings. The combination and evolution of technology is forming a complex, self-organizing, and evolving scale-free network. Originating from a technological system, key and core technology is the cornerstone to boosting economic and social progress. To develop a more sustainably focused planet, key and core technologies will play an increasingly vital role.

13.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-847258

RESUMO

BACKGROUND: China is a country with high incidence of liver disease. Liver tissue engineering, which is still in the stage of exploration, has brought a new hope for treatment. OBJECTIVE: To provide advices and references for the development and innovation of liver tissue engineering based on patent analysis. METHODS: The number and development tendency, as well as the technology birthplace, target market, applicants, inventors and technical fields of patents in the field of liver tissue engineering in nearly 20 years were analyzed in this study. The keywords for full-text search included tissue engineering, tissue regenerate/repair, and hepatic/liver. The retrieval deadline was December 28, 2018. RESULTS AND CONCLUSION: There is a rapid development in the field of the global liver tissue engineering. The compound growth rate in the past 10 years is 8.64%, of which invention patents account for 84.93%. China is the main technology birthplace; however, the number of tripartite patents of China is far less than that of the United States and Japan. China and the United States are the two most high-profile target markets in the field of liver tissue engineering, but the applicants are mostly from native instead of international. Meanwhile, there are 8 Chinese application institutions and 14 Chinese inventors ranking among the top 20 in the world in this field. In conclusion, liver tissue engineering has developed rapidly in China, but the lack of core technology is still an important issue. Therefore, we must improve our innovation capabilities and explore core technologies continuously to enhance our international competitiveness.

14.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 50(6): 787-791, 2019 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-31880106

RESUMO

Critical Care Ultrasound(CCUS)is the one of the ultrasound technologies which integrates the bedside ultrasound application into daily clinical practice in critical care medicine. It has multiple roles, at first is a non-invasive monitoring tool to measure variables that can reflect the essence of the disease, and then is a comprehensive visualized tool to evaluate the pathophysiological status and structural changes of organs, which facilitates the critical care providers to know more about the patients and provides more reliable evidence to promote the accuracy and efficiency of the diagnosis, the clinical decision-making and the treatment of the critically ill. Therefore, the critical care ultrasound has been used as one of the core technologies of critical care. The characteristics and advantages of CCUS destine it as an orientation and instruction of visualized diagnosis and treatment. We devote ourselves to explore methods of integrating the application of CCUS into clinical management of critically ill, and establish specific approaches and workflows to standardize the clinical practice of clinicians and reduce medical errors. Therefore, a new diagnostic and treatment pattern can be developed, which is called visualized critical care. It is a care pattern of critical illness based on the CCUS visualization evidence including the pathophysiological status and other informations. This article will carefully discuss the connotation of CCUS, the unique clinical value in critically ill patients, and the value of visualized critical care approaches in acute respiratory and circulatory collapse and shock management, etc..


Assuntos
Cuidados Críticos , Estado Terminal , Humanos , Ultrassonografia
15.
Front Plant Sci ; 10: 455, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31057572

RESUMO

Dengue fever is currently ranked as the top emerging tropical disease, driven by increased global travel, urbanization, and poor hygiene conditions as well as global warming effects which facilitate the spread of Aedes mosquitoes beyond their current distribution. Today, more than 100 countries are affected most of which are tropical Asian and Latin American nations with limited access to medical care. Hence, the development of a dengue vaccine that is dually cost-effective and able to confer a comprehensive protection is ultimately needed. In this study, a consensus sequence of the antigenic dengue viral glycoprotein domain III (cEDIII) was used aiming to provide comprehensive coverage against all four circulating dengue viral serotypes and potential clade replacement event. Utilizing hepatitis B tandem core technology, the cEDIII sequence was inserted into the immunodominant c/e1 loop region so that it could be displayed on the spike structures of assembled particles. The tandem core particles displaying cEDIII epitopes (tHBcAg-cEDIII) were successfully produced in Nicotiana benthamiana via Agrobacterium-mediated transient expression strategy to give a protein of ∼54 kDa, detected in both soluble and insoluble fractions of plant extracts. The assembled tHBcAg-cEDIII virus-like particles (VLPs) were also visualized from transmission electron microscopy. These VLPs had diameters that range from 32 to 35 nm, presenting an apparent size increment as compared to tHBcAg control particles without cEDIII display (namely tEL). Mice immunized with tHBcAg-cEDIII VLPs showed a positive seroconversion to cEDIII antigen, thereby signifying that the assembled tHBcAg-cEDIII VLPs have successfully displayed cEDIII antigen to the immune system. If it is proven to be successful, tHBcAg-cEDIII has the potential to be developed as a cost-effective vaccine candidate that confers a simultaneous protection against all four infecting dengue viral serotypes.

16.
Anal Chim Acta ; 1033: 205-212, 2018 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-30172328

RESUMO

Core-shell particle is a new generation high performance packing material for liquid chromatography. Through comparison with a classical totally porous silica phase of the same particle size, we studied Ascentis Express 5 µm core-shell particle's electrochromatographic behavior, in terms of voltage-current property, electroosmotic flow (EOF) and van Deemter curve. It was found, due to the nonpermeable solid core, the core-shell particle presented a diminished EOF and efficiency than the totally porous paricle. This on the other hand proved that the intra-particle pore flow extensively exists and plays an important role in electrochromatography on totally porous material. The core-shell particle's high retentivity led to an enhanced resolution for weakly retained hydrophilic peptides, which were poorly retained and co-eluted on totally porous particles. Further exploration has shown the core-shell material can achieve efficient electrochromatography of protein digests, excellent performance in terms of resolution, reproducibility and long term stability have been observed. The results indicate that the core-shell structure may suggest a reasonable design of stationary phase for bioelectrochromatography of peptides and proteins.


Assuntos
Eletrocromatografia Capilar , Peptídeos/química , Proteínas/química , Tamanho da Partícula , Porosidade , Propriedades de Superfície
17.
R Soc Open Sci ; 4(6): 170288, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28680682

RESUMO

Prepared core technology illustrates in-depth planning and the presence of a mental template during the core reduction process. This technology is, therefore, a significant indicator in studying the evolution of abstract thought and the cognitive abilities of hominids. Here, we report on Victoria West cores excavated from the Canteen Kopje site in central South Africa, with a preliminary age estimate of approximately 1 Ma (million years ago) for these cores. Technological analysis shows that the Victoria West cores bear similarities to the 'Volumetric Concept' as defined for the Levallois, a popular and widely distributed prepared core technology from at least 200 ka (thousand years ago). Although these similarities are present, several notable differences also occur that make the Victoria West a unique and distinctive prepared core technology; these are: elongated and convergent core shapes, consistent blow directions for flake removal, a predominance of large side-struck flakes, and the use of these flakes to make Acheulean large cutting tools. This innovative core reduction strategy at Canteen Kopje extends the roots of prepared core technology to the latter part of the Early Acheulean and clearly demonstrates an increase in the cognitive abilities and complexities of hominids in this time period.

18.
J Steroid Biochem Mol Biol ; 162: 117-25, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-26924583

RESUMO

Bile acids (BAs) are present in follicular fluid (FF) from humans and cattle. This fact has triggered an interest on the role BAs might play in folliculogenesis and their possible association with fertility. To achieve a better understanding about this subject, new methods are needed to provide reliable information about concentrations of the most important BAs in FF. In this context, liquid chromatography-tandem mass spectrometry (LC-MS/MS) offers high specificity with a relatively simple sample workup. We developed and validated a new assay for the quick profiling of the 9 most abundant BAs in follicular fluid from cattle. The method uses 200µl of FF and can quantify cholic acid (CA), chenodeoxycholic acid (CDCA), deoxycholic acid (DCA) and their glycine (G) and taurine (T) conjugates. Lithocholic acid (LCA), its conjugates GLCA and TLCA, and sulfated forms, were present in some samples, but their concentration was low compared to other BAs (in average, below 60ng/ml for LCA, GLCA or TLCA and below 20ng/ml for their corresponding sulfates). Method performance was studied at three quality controls for each compound in consonance with their physiological concentration. Excellent linearity and recovery were found for all compounds at every control level. Intra-day and between-day precisions (%CV) and accuracies (relative errors) were below 15% for all the compounds. Matrix effects were negligible for most of the analytes. Samples undergoing freeze-thaw showed no degradation of their BAs. The method makes use of a fused-core phenyl column coupled to a triple quadrupole tandem mass spectrometer to achieve chromatographic separation within 5min. We quantified BAs grouped in four different follicle sizes (3-5mm, 6-8mm, 9-14mm, >15mm), obtaining a similar relative BA profile for all the sizes, with CA always in higher concentration, ranging between 1600 and 18000ng/ml, approximately, followed by its conjugate glycocholic acid, GCA, which ranged between 800 and 9000ng/ml. The highest concentration in CA, DCA or CDCA was always detected in FF stemming from follicles of 6-8mm. To our knowledge, this is the first report in which BAs subspecies have been detected and quantified in bovine follicular fluid.


Assuntos
Ácidos e Sais Biliares/análise , Líquido Folicular/química , Animais , Bovinos , Ácido Quenodesoxicólico/análise , Ácido Cólico/análise , Cromatografia Líquida de Alta Pressão/métodos , Ácido Desoxicólico/análise , Feminino , Limite de Detecção , Ácido Litocólico/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos
19.
J Control Release ; 213: 10-17, 2015 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-26130417

RESUMO

Ziprasidone, like many BCS Class II drugs with low intrinsic solubility and a strong tendency to crystallize from supersaturated solutions, presents significant technical challenges when developing an oral controlled release dosage form. In order to achieve acceptable bioavailability and prolonged exposures for once-daily dosing, good colonic absorption and a reliable controlled release (CR) technology are necessary. To this end, a novel solubilized drug form--coated crystals made by spray drying (CCSD), was formulated and progressed into human clinical studies. This report describes studies of colonic absorption for the CCSD using the Enterion™ capsule and a pharmacoscintigraphy study in which the CCSD was orally administered via a radiolabelled osmotic tablet formulation. These studies demonstrated that the probability of achieving the required drug solubilization in the colon with the CCSD concept and thereby the desired once daily pharmacokinetic profile was extremely low.


Assuntos
Antipsicóticos/administração & dosagem , Preparações de Ação Retardada/química , Piperazinas/administração & dosagem , Tiazóis/administração & dosagem , Administração Oral , Antipsicóticos/farmacocinética , Disponibilidade Biológica , Cápsulas , Colo/metabolismo , Humanos , Absorção Intestinal , Piperazinas/farmacocinética , Cintilografia , Solubilidade , Tiazóis/farmacocinética
20.
J Chromatogr A ; 1365: 131-9, 2014 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-25242223

RESUMO

A simple, sensitive and fast hydrophilic interaction liquid chromatography (HILIC) method using ultraviolet diode-array detector (UV-DAD)/electrospray ionization tandem mass spectrometry was developed for the automated high performance liquid chromatography (HPLC) determination of sodium risedronate (SR) and its degradation products in new pharmaceuticals. The chromatographic separations were performed on Ascentis Express HILIC 2.7µm (150mm×2.1mm, i.d.) stainless steel column (fused core). The mobile phase consisted of formate buffer solution (pH 3.4; 0.03M)/acetonitrile 42:58 and 45:55 (v/v) for granules for oral solution and effervescent tablet analysis, respectively, at a flow-rate of 0.2mL/min, setting the wavelength at 262nm. Stability characteristics of SR were evaluated by performing stress test studies. The main degradation product formed under oxidation conditions corresponding to sodium hydrogen (1-hydroxy-2-(1-oxidopyridin-3-yl)-1-phosphonoethyl)phosphonate was characterized by high performance liquid chromatography-electrospray ionization-mass tandem mass spectrometry (HPLC-ESI-MS/MS). The validation parameters such as linearity, sensitivity, accuracy, precision and selectivity were found to be highly satisfactory. Linear responses were observed in standard and in fortified placebo solutions. Intra-day precision (relative standard deviation, RSD) was ≤1.1% for peak area and ≤0.2% for retention times (tR) without significant differences between intra- and inter-day data. Recovery studies showed good results for all the examined compounds (from 98.7 to 101.0%) with RSD ranging from 0.6 to 0.7%. The limits of detection (LOD) and quantitation (LOQ) were 1 and 3ng/mL, respectively. The high stability of standard and sample solutions at room temperature means an undoubted advantage of the method allowing the simultaneous preparation of many samples and consecutive chromatographic analyses by using an autosampler. The developed stability indicating method is suitable for the quality control of SR in new and commercial pharmaceutical formulations.


Assuntos
Conservadores da Densidade Óssea/análise , Ácido Etidrônico/análogos & derivados , Cromatografia Líquida de Alta Pressão/métodos , Ácido Etidrônico/análise , Interações Hidrofóbicas e Hidrofílicas , Limite de Detecção , Controle de Qualidade , Reprodutibilidade dos Testes , Ácido Risedrônico , Espectrometria de Massas por Ionização por Electrospray/métodos , Comprimidos , Espectrometria de Massas em Tandem/métodos
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