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1.
BMC Med Imaging ; 24(1): 11, 2024 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-38172764

RESUMO

BACKGROUND: To validate the feasibility of water enema PET/CT (WE-PET/CT) in incidental colorectal 18F-FDG uptake and improve the accuracy of diagnosing colorectal neoplastic lesions. METHODS: We retrospectively analysed the electronic records of 338 patients undergoing common PET/CT and WE-PET/CT at our hospital. PET/CT results were correlated with colonoscopy pathology and follow-up results. The ROC contrast curve was plotted to evaluate the accuracy of SUVmax on common PET/CT and WE-PET/CT for detecting neoplastic lesions. SUVmax and the median retention indexes (RIs) of cancerous, precancerous, and benign lesions and physiologic uptake were compared. RESULTS: The sensitivity, specificity and accuracy of diagnosing neoplastic lesions with common PET/CT were 84.0%, 78.3% and 80.2%, respectively. The corresponding results with WE-PET/CT were 95.8%, 96.5% and 96.2%. The AUC of SUVmax on WE-PET/CT was significantly higher than that on common PET/CT (0.935 vs. 0.524, p < 0.001). The median SUVmax on WE-PET/CT was significantly higher than that on common PET/CT in cancerous and precancerous lesions, and significantly decreased in benign lesions and physiologic uptake (p < 0.001). The RI was significantly different between cancerous lesions and physiologic uptake, between precancerous lesions and physiologic uptake, between benign lesions and physiologic uptake, and between cancerous and benign lesions (p < 0.05). CONCLUSIONS: WE-PET/CT is a noninvasive, well-tolerated and effective technique for diagnosing incidental colorectal 18F-FDG uptake. It is helpful for a timely colonoscopy and can effectively avoid an unnecessary colonoscopy for incidental colorectal 18F-FDG uptake.


Assuntos
Neoplasias Colorretais , Lesões Pré-Cancerosas , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Fluordesoxiglucose F18 , Água , Estudos Retrospectivos , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos , Achados Incidentais , Neoplasias Colorretais/diagnóstico , Enema
2.
J Med Virol ; 95(8): e29050, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37635425

RESUMO

A novel virus-like particle (VLP)-based multivalent recombinant human papillomavirus (HPV) vaccine was developed and evaluated in human, including 14 HPV-type specific VLP antigens (HPV6, 11, 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, and 59). The pseudovirus-based neutralizing assay (PBNA) method is widely used for immunogenicity assessment of HPV vaccine in clinical trials. However, as many as 14 antigen-specific antibody levels need be determined, PBNA is, for many reasons, challenging and time-consuming. In this study, we developed a Luminex immunological assay (LIA) and a competitive Luminex immunological assay (cLIA). These methods increase the throughput, reproducibility and precision, as well as reduce the complexity. All assay parameters showed good characteristics in the validation of both methods, benefiting from highly purified and structurally correct VLPs, high specific antibodies, standard VLP-microspheres and PE-mAbs conjugating process, adequate assay development and stable system. Validation data support the use of both methods for immunogenicity assessment in clinical trials. LIA showed higher sensitivity than cLIA, and due to limited epitopes of mAb, cLIA detected lower antibody responses, and therefore, fewer antibodies. This work not only supports clinical trials of 14-valent HPV vaccines more efficiently and reliably, but also provides a set of validation strategies and usable standards for general vaccine immunogenicity testing.


Assuntos
Infecções por Papillomavirus , Vacinas contra Papillomavirus , Humanos , Papillomavirus Humano , Infecções por Papillomavirus/prevenção & controle , Reprodutibilidade dos Testes , Vacinas Combinadas , Anticorpos Monoclonais , Antígenos Virais
3.
Front Reprod Health ; 5: 1167868, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37408999

RESUMO

Introduction: We illustrate a comprehensive tampon safety assessment approach that assures products can be used safely. Material biocompatibility, vaginal mucosa assessment, vaginal microbiome evaluation, and in vitro assessment of potential risk of staphylococcal toxic shock syndrome expressed through growth of Staphylococcus aureus (S. aureus) and production of TSST-1 are the four essential portions of the approach. Post-marketing surveillance informs of possible health effects that warrant follow up. The approach meets or exceeds US and international regulatory guidance and is described through the example of four tampon products. Methods/Results: Each product is comprised mostly of large molecular weight components (cotton, rayon, polymers) that cannot pass the vaginal mucosa, are widely used across the industry, and replete with a vast body of safety data and a long history of safe use in the category. Quantitative risk assessment of all small molecular weight components assured a sufficient margin of safety supporting their use. Vaginal mucosa assessment confirmed that pressure points, rough edges and/or sharp contact points were absent. A randomized cross-over clinical trial (ClinicalTrials.gov Identifier: NCT03478371) revealed favorable comfort ratings, and few complaints of irritation, burning, stinging, or discomfort upon insertion, wear, and removal. Adverse events were few, mild in severity, self-limited and resolved without treatment. Vaginal microbiota assessment in vitro presented no adverse effect on microbial growth. Culture-independent microbiome analyses from vaginal swab samples obtained during the clinical trial showed no differences attributable to tampon usage, but instead due to statistically significant subject-to-subject variability. Growth of S. aureus and TSST-1 toxin production in the presence of any of the four products in vitro were statistically significantly reduced when compared to medium control alone. Discussion: The data from the four elements of the comprehensive safety assessment approach illustrated herein confirm that tampons evaluated using this system can be used safely for menstrual protection. A post-marketing surveillance system that monitors and responds to in-market experiences indicated in-use tolerability of the product among consumers, thus confirming the conclusions of the pre-marketing safety assessment.

4.
EBioMedicine ; 86: 104339, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36370636

RESUMO

BACKGROUND: Ensuring menstrual cup safety is paramount, yet a menstrual cup safety assessment scheme is lacking. This paper presents a quadripartite scheme, showing how it can be applied. METHODS: The Tampax Menstrual Cup was evaluated in the safety assessment scheme: (1) Biocompatibility and chemical safety of cup constituents. Extractables were obtained under different use condition; exposure-based risk assessments (EBRA) were conducted for extractables exceeding thresholds of toxicological concern. (2) Physical impact to vaginal mucosa. After physical evaluations, the Tampax Cup and another cup were assessed in a randomised double-blinded, two-product, two-period cross-over clinical trial (65 women, mean age 34.2 years). (3) Impact to vaginal microbiota (in vitro mixed microflora assay and evaluation of vaginal swabs). (4) In vitro growth of Staphylococcus aureus and toxic shock syndrome toxin-1 (TSST-1) production. FINDINGS: Biocompatibility assessments and EBRA of cup constituents showed no safety concerns. In the randomised clinical trial, all potentially product-related adverse effects were mild, vaginal exams were unremarkable, no clinically relevant pH changes occurred, post-void residual urine volume with and without cup were similar, and self-reported measures of comfort along with reports of burning, itching and stinging between cups were comparable. Cup use had no effect on microbial growth in vitro or in the 62 subjects who completed the trial or on in vitro TSST-1 production. INTERPRETATION: The quadripartite safety assessment scheme allows evaluation of menstrual cup safety. The Tampax Cup is safe and well-tolerated upon intended use. As with all feminine hygiene products, post-market safety surveillance confirmed this conclusion. FUNDING: By Procter & Gamble.


Assuntos
Produtos de Higiene Menstrual , Infecções Estafilocócicas , Feminino , Humanos , Adulto , Produtos de Higiene Menstrual/efeitos adversos , Silicones , Staphylococcus aureus , Vagina
5.
Polymers (Basel) ; 13(5)2021 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-33673625

RESUMO

3D printing technology is a versatile technology. The waste of 3D printed plastic products is a matter of concern because of its impact on the circular economy. In this paper, we discuss the current status and problems of 3D printing, different methods of 3D printing, and applications of 3D printing. This paper focuses on the recycling and degradation of different 3D printing materials. The degradation, although it can be done without pollution, has restrictions on the type of material and time. Degradation using ionic liquids can yield pure monomers but is only applicable to esters. The reprocessing recycling methods can re-utilize the excellent properties of 3D printed materials many times but are limited by the number of repetitions of 3D printed materials. Although each has its drawbacks, the great potential of the recycling of 3D printed waste plastics is successfully demonstrated with examples. Various recycling approaches provide the additional possibility of utilizing 3D printing waste to achieve more efficient circular application.

6.
Surg Endosc ; 35(5): 2297-2305, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-32444970

RESUMO

BACKGROUND: Laparoscopic cholecystectomy (LC) is the standard treatment for acute cholecystitis (AC), and it should be performed within 72 h of symptoms onset if possible. In many undesired situations, LC was performed beyond the golden 72 h. However, the safety and feasibility of prolonged LC (i.e., performed more than 72 h after symptoms onset) are largely unknown, and therefore were investigated in this study. METHODS: We retrospectively enrolled the adult patients who were diagnosed as AC and were treated with LC at the same admission between January 2015 and October 2018 in an emergency department of a tertiary academic medical center in China. The primary outcome was the rate and severity of adverse events, while the secondary outcomes were length of hospital stay and costs. RESULTS: Among the 104 qualified patients, 70 (67.3%) underwent prolonged LC and 34 (32.7%) underwent early LC (< 72 h of symptom onset). There were no differences between the two groups in mortality rate (none for both), conversion rates (prolonged LC 5.4%, and early LC 8.8%, P = 0.68), intraoperative and postoperative complications (prolonged LC 5.7% and early LC 2.9%, P ≥ 0.99), operation time (prolonged LC 193.5 min and early LC 198.0 min, P = 0.81), and operation costs (prolonged LC 8,700 Yuan, and early LC 8,500 Yuan, P = 0.86). However, the prolonged LC was associated with longer postoperative hospitalization (7.0 days versus 6.0 days, P = 0.03), longer total hospital stay (11.0 days versus 8.0 days, P < 0.01), and subsequently higher total costs (40,400 Yuan versus 31,100 Yuan, P < 0.01). CONCLUSIONS: Prolonged LC is safe and feasible for patients with AC for having similar rates and severity of adverse events as early LC, but it is also associated with longer hospital stay and subsequently higher total cost.


Assuntos
Colecistectomia Laparoscópica/efeitos adversos , Colecistectomia Laparoscópica/métodos , Colecistite Aguda/cirurgia , Adulto , Colecistectomia Laparoscópica/economia , Colecistite Aguda/economia , Estudos de Viabilidade , Feminino , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Tempo para o Tratamento , Resultado do Tratamento
7.
ACS Appl Mater Interfaces ; 10(33): 27955-27964, 2018 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-30051711

RESUMO

Carbon fiber (CF)-reinforced ceramic composites show the attractive potential for next generation thermal protection materials because of their outstanding reliability and excellent high-temperature resistance but are facing great challenges in the combination of the engineering practicality and versatility. Herein, it is demonstrated that silicon carbide nanowires can be grown on the surface of CF to create a multifunctional thermal barrier application composite. The embedding of the silicon carbide nanowires in the interface of CF and ceramic matrix significantly increased the structural health monitoring sensitivity and interface strength of the composites. Compared to the conventional CF/ZrC composites, the structural health monitoring sensitivity of the composites with SiC nanowires is greatly elevated with a 14-fold improvement. Additional investigations revealed that the multifunctional SiCnws-CF/ZrC nanocomposites enjoyed a low thermal conductivity of 0.49 W/(m·K), a light weight (0.76-1.85 g/cm3), and a relative high compressive strength of 23.64 MPa, which is favorite in applying as a thermal barrier material. Furthermore, the interface design strategy could be extended as a universal method in fabricating various fiber-reinforced composites for a wide range of other applications.

8.
Artigo em Inglês | MEDLINE | ID: mdl-29206192

RESUMO

The aim of this study is to evaluate the influence of public service advertising on the awareness and attitude of Chongqing urban citizens. The theme of the public service advertisement launched in Chongqing was chronic disease prevention and control. A self-designed questionnaire was used in an outdoor intercept survey to collect information about the perception of citizens toward the effect of the advertisement on awareness and attitude situation. Respondents had good knowledge of chronic disease (17.11 ± 3.23, total score: 23), but only 58.4% of participants thought cancer is one type of chronic disease. The awareness of cancer as a chronic disease among the group who had seen this advertisement (63.6%) was higher than that of the group who had not seen the advertisement (56.5%) (p = 0.046). The attitude of respondents was good after watching the advertisement, approximately 77.4% of respondents attempted to remind their family and friends to prevent chronic diseases, roughly. 78.2% tried to persuade their family and friends to change their unhealthy lifestyle habits, and 84.7% of participants reported that the advertising increased the possibility of their own future lifestyle change. There was minimal change of awareness of the participants who saw the advertisement. This study did not show significant differences on chronic disease related knowledge between the participants who have seen the advertisement and who have not seen the advertisement. The public service advertisement may help participants improve the attitude of future behavior change. Further researches combining the sustained intervention and support through clinical and community health programs media campaigns are needed to support public health.


Assuntos
Publicidade , Conhecimentos, Atitudes e Prática em Saúde , Promoção da Saúde/métodos , Prevenção Primária , Anúncios de Utilidade Pública como Assunto , População Urbana/estatística & dados numéricos , Adulto , China , Doença Crônica , Estudos Transversais , Feminino , Amigos , Hábitos , Humanos , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Adulto Jovem
9.
J Sep Sci ; 40(20): 3987-3995, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28795490

RESUMO

The content of styrene units in nonhydrogenated and hydrogenated styrene-butadiene-styrene and styrene-isoprene-styrene triblock copolymers significantly influences product performance. A size exclusion chromatography method was developed to determine the average styrene content of triblock copolymers blended with tackifier in adhesives. A complete separation of the triblock copolymer from the other additives was realized with size exclusion chromatography. The peak area ratio of the UV and refraction index signals of the copolymers at the same effective elution volume was correlated to the average styrene unit content using nuclear magnetic resonance spectroscopy with commercial copolymers as standards. The obtained calibration curves showed good linearity for both the hydrogenated and nonhydrogenated styrene-butadiene-styrene and styrene-isoprene-styrene triblock copolymers (r = 0.974 for styrene contents of 19.3-46.3% for nonhydrogenated ones and r = 0.970 for the styrene contents of 23-58.2% for hydrogenated ones). For copolymer blends, the developed method provided more accurate average styrene unit contents than nuclear magnetic resonance spectroscopy provided. These results were validated using two known copolymer blends consisting of either styrene-isoprene-styrene or hydrogenated styrene-butadiene-styrene and a hydrocarbon tackifying resin as well as an unknown adhesive with styrene-butadiene-styrene and an aromatic tackifying resin. The methodology can be readily applied to styrene-containing polymers in blends such as poly(acrylonitrile-butadiene styrene).

10.
Sci Rep ; 7(1): 7427, 2017 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-28785026

RESUMO

Here, we aimed to validate a noninvasive method using capture sequencing for prenatal diagnosis of congenital adrenal hyperplasia due to 21-Hydroxylase deficiency (21-OHD). Noninvasive prenatal diagnosis (NIPD) of 21-OHD was based on 14 plasma samples collected from 12 families, including four plasma sample collected during the first trimester. Targeted capture sequencing was performed using genomic DNA from the parents and child trios to determine the pathogenic and wild-type alleles associated with the haplotypes. Maternal plasma DNA was also sequenced to determine the fetal inheritance of the allele using hidden Markov model-based haplotype linkage analysis. The effect of fetal DNA fraction and sequencing depth on the accuracy of NIPD was investigated. The lower limit of fetal DNA fraction was 2% and the threshold mean sequence depth was 38, suggesting potential advantage if used in early gestation. The CYP21A2 genotype of the fetus was accurately determined in all the 14 plasma samples as early as day 1 and 8 weeks of gestation. Results suggest the accuracy and feasibility of NIPD of 21-OHD using a small target capture region with a low threshold for fetal DNA fraction and sequence depth. Our method is cost-effective and suggests diagnostic applications in clinical practice.


Assuntos
Hiperplasia Suprarrenal Congênita/diagnóstico , DNA/isolamento & purificação , Técnicas de Diagnóstico Molecular/métodos , Plasma/química , Diagnóstico Pré-Natal/métodos , Análise de Sequência de DNA/métodos , Análise Custo-Benefício , DNA/química , DNA/genética , Genótipo , Humanos , Esteroide 21-Hidroxilase/genética
11.
Clin Interv Aging ; 12: 673-678, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28442897

RESUMO

AIM: Pharmacoeconomic cost-effectiveness analysis of two different dosage regimens of levofloxacin in the treatment of acute lower respiratory tract infection in elderly patients. METHODS: A total of 108 elderly patients with acute lower respiratory tract infection who visited by our hospital between September 2013 and September 2014 were randomly divided into Group A and Group B, with 54 patients in each group. In Group A, levofloxacin injection was given for continuous intravenous infusion treatment, whereas in Group B, levofloxacin injection and levofloxacin capsule were given as sequential therapy (ST). The period of treatment for both the groups was 10 days, and minimum cost analysis was used to analyze the treatment. RESULTS: Groups A and B had cure rates of 61.1% and 59.3% (P>0.05), effective rates of 88.9% and 83.3% (P>0.05), bacterial clearance rates of 96.3% and 92.6% (P>0.05), and incidence rates of adverse reactions of 7.4% and 3.7% (P>0.05), respectively. Treatment costs of Groups A and B were 1,588 RMB and 1,150 RMB, respectively, whereas the cost-effectiveness of the two groups was at 17.86 and 13.81, respectively (P<0.05). CONCLUSION: Levofloxacin ST had relatively higher cost-effectiveness ratio for the treatment of acute lower respiratory tract infection in elderly patients, especially Chinese.


Assuntos
Antibacterianos/administração & dosagem , Antibacterianos/economia , Levofloxacino/administração & dosagem , Levofloxacino/economia , Infecções Respiratórias/tratamento farmacológico , Doença Aguda , Administração Oral , Idoso , Antibacterianos/uso terapêutico , Análise Custo-Benefício , Feminino , Humanos , Infusões Intravenosas , Levofloxacino/uso terapêutico , Masculino , Pessoa de Meia-Idade
12.
Artigo em Inglês | MEDLINE | ID: mdl-27420075

RESUMO

In many countries the frequency of eating out has steadily increased over the last few decades, and this behavioris often associated with unhealthy dietary patterns. This study aimed to describe the levels of knowledge, attitude, and behaviors (KAB) related to eating out among university students. A cross-sectional study was conducted in the college town in Chongqing, China with a total of 1634 participants. The mean eating out related KAB scores were: knowledge 11.5 ± 2.9, attitude 17.0 ± 2.8, and behaviors 24.2 ± 4.8 (possible total scores: 20, 24, 40 respectively). As the level of knowledge increased, the percentage of highly satisfactory attitude and behaviors increased. Only 10% of the participants did not eat out for lunch and dinner during weekends in the last month. Gender, ethnicity, mother's education, monthly boarding expenses, living place during the study, and the frequency of eating out for breakfast were statistically associated with the scores of KAB. In conclusion, Chinese junior students had poor knowledge of and behaviors towards eating out and ate out frequently. Educational interventionsto improve knowledge related eating out are needed in order to promote healthy eating out behaviors among Chinese university students.


Assuntos
Comportamento Alimentar , Conhecimentos, Atitudes e Prática em Saúde , Estudantes/psicologia , Estudantes/estatística & dados numéricos , Universidades , Adolescente , Fatores Etários , China , Estudos Transversais , Feminino , Humanos , Masculino , Grupos Raciais , Fatores Sexuais , Fatores Socioeconômicos , Adulto Jovem
13.
Asia Pac J Public Health ; 27(2 Suppl): 93S-9S, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25504115

RESUMO

The purpose of the study was to investigate the noise pollution situation and the resulting adverse effect on residents' health in Luzhou, China, to provide data for noise pollution prevention policies and interventions. Four different functional areas (commercial, construction, residential, and transportation hub areas) were chosen to monitor noise level for 3 months. The survey was performed by questionnaire on the spot on randomly selected individuals; it collected data on the impact of noise on residents' health (quality of sleep, high blood pressure, subjective feeling of nervous system damage, and attention) as well as the knowledge of noise-induced health damage, the degree of adaptation to noise, and their solutions. The noise levels of residential, commercial, transportation, and construction areas exceeded the national standards (P < .001). Sleep quality, prevalence of hypertension, and attention in transportation hub areas were significantly different from those in the other 3 areas (P < .05); only 24.46% of people knew the health hazards associated with noise; 64.57% of residents have adapted to the current noise environment. Most of them have to close the doors and windows to reduce noise. The noise pollution situation in Luzhou, China, is serious, especially the traffic noise pollution. Residents pay less attention to it and adopt single measures to reduce the noise. We should work toward the prevention and control of traffic noise and improve the residents' awareness to reduce the adverse health effects of noise.


Assuntos
Ruído/efeitos adversos , Características de Residência , Adolescente , Adulto , Idoso , Atenção , Pressão Sanguínea , Criança , China/epidemiologia , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Habitação , Humanos , Masculino , Pessoa de Meia-Idade , Ruído dos Transportes/efeitos adversos , Sono , Inquéritos e Questionários , Meios de Transporte , Adulto Jovem
14.
Open Biomed Eng J ; 8: 68-74, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25337150

RESUMO

The existing Elders Health Assessment (EHA) system based on single-case-library reasoning has low intelligence level, poor coordination, and limited capabilities of assessment decision support. To effectively support knowledge reuse of EHA system, this paper proposes collaborative case reasoning and applies it to the whole knowledge reuse process of EHA system. It proposes a multi-case library reasoning application framework of EHA knowledge reuse system, and studies key techniques such as case representation, case retrieval algorithm, case optimization and correction, and reuse etc.. In the aspect of case representation, XML-based multi-case representation for case organization and storage is applied to facilitate case retrieval and management. In the aspect of retrieval method, Knowledge-Guided Approach with Nearest-Neighbor is proposed. Given the complexity of EHA, Gray Relational Analysis with weighted Euclidean Distance is used to measure the similarity so as to improve case retrieval accuracy.

15.
Artigo em Inglês | MEDLINE | ID: mdl-24779908

RESUMO

Results of a survey of levels of ethyl carbamate (EC) (urethane) in alcoholic beverages carried out in four successive years from 2009 to 2012 by gas chromatography-mass spectrometry (GC/MS) are presented. The beverages were purchased for sampling from Hebei Province of China, including eight main areas of production. The samples comprised wines (n = 212), grain spirits (n = 143) and wine sauces (n = 164). The data show that the average EC content in these kinds of alcoholic beverages remains nearly constant over the years. The results provide valuable data for food authorities to establish maximum limits for EC in China.


Assuntos
Bebidas Alcoólicas/análise , Carcinógenos/análise , Contaminação de Alimentos , Mutagênicos/análise , Uretana/análise , Bebidas Alcoólicas/economia , China , Condimentos/análise , Condimentos/economia , Dieta/etnologia , Inspeção de Alimentos , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Limite de Detecção , Reprodutibilidade dos Testes , Análise Espaço-Temporal , Vinho/análise , Vinho/economia
16.
Arch Pharm Res ; 32(5): 667-76, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19471880

RESUMO

This study systematically investigated the retention behavior of seven neutral ginsenosides Rg(1), Re, Rf, Rb(1), Rb(2), Rc, Rd, and an acidic ginsenoside R(0), the major pharmacologically active components of Radix Ginseng with RP-HPLC. The effects of solvent, pH value, ionic strength of the mobile phase, and column temperature were investigated using an octadecylsiloxane-bonded silica gel column. Based on the ginsenosides' retention characteristics, the concentration of acetonitrile and the gradient of the mobile phase needed to maintain the baseline separation of the major neutral ginsenosides in Radix Ginseng were theoretically predicted. Furthermore, the ionic strength of mobile-phase necessary to achieve good resolution of the neutral ginsenosides and acidic ginsenosides was carefully investigated. According to the results of the quantitative analysis of ginsenosides in eight batches of ginseng samples from different sources, the developed HPLC technique may be a valuable tool for the quality assessment of Radix Ginseng.


Assuntos
Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas/química , Ginsenosídeos/isolamento & purificação , Panax/química , Acetonitrilas/química , Medicamentos de Ervas Chinesas/normas , Concentração de Íons de Hidrogênio , Modelos Químicos , Concentração Osmolar , Raízes de Plantas , Controle de Qualidade , Reprodutibilidade dos Testes , Solventes/química , Temperatura
17.
Arch Pharm Res ; 31(10): 1265-73, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18958416

RESUMO

This study systematically investigated the retention behavior of seven neutral ginsenosides Rg(1), Re, Rf, Rb(1), Rb(2), Rc, Rd, and an acidic ginsenoside R(0), the major pharmacologically active components of Radix Ginseng with RP-HPLC. The effects of solvent, pH value, ionic strength of the mobile phase, and column temperature were investigated using an octadecylsiloxane-bonded silica gel column. Based on the ginsenosides' retention characteristics, the concentration of acetonitrile and the gradient of the mobile phase needed to maintain the baseline separation of the major neutral ginsenosides in Radix Ginseng were theoretically predicted. Furthermore, the ionic strength of mobile-phase necessary to achieve good resolution of the neutral ginsenosides and acidic ginsenosides was carefully investigated. According to the results of the quantitative analysis of ginsenosides in eight batches of ginseng samples from different sources, the developed HPLC technique may be a valuable tool for the quality assessment of Radix Ginseng.


Assuntos
Ginsenosídeos/química , Panax/química , Algoritmos , Cromatografia Líquida de Alta Pressão , Concentração de Íons de Hidrogênio , Indicadores e Reagentes , Controle de Qualidade , Temperatura
18.
Biomacromolecules ; 7(8): 2327-30, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16903678

RESUMO

In this paper, we prepared composite fibers via electrospinning from either W/O or O/W emulsion. SEM images demonstrate the beads-in-string structures in these fibers and proved this technique to be an effective method for microencapsulation. As a practical application, Ca-alginate microspheres, which serve as reservoirs for hydrophilic drugs, were prepared in a reverse emulsion and then incorporated into poly (l-lactic acid) (PLLA) fibers by electrospinning. With the bovine serum albumin (BSA) loaded into the microspheres, the beads-in-string structure thus entrapped hydrophilic proteins in hydrophobic polymeric matrix. In the in vitro release test, BSA, which was released from composite fibers, achieved prolonged release profiles and lower burst release rates than those from naked Ca-alginate microspheres. In comparison with other well-established techniques to prepare microcapsules, such as solvent evaporation and spray-drying techniques, emulsion electrospinning features partly competing, partly complementary characteristics. Extension to other emulsion systems will be able to fabricate new types of functional structures.


Assuntos
Alginatos/química , Lactatos/química , Microesferas , Nanoestruturas/química , Soroalbumina Bovina/química , Animais , Bovinos , Preparações de Ação Retardada/química , Dessecação , Emulsões , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Interações Hidrofóbicas e Hidrofílicas , Microscopia Eletrônica de Varredura
19.
Chem Pharm Bull (Tokyo) ; 53(6): 705-9, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15930789

RESUMO

An HPLC-ESI-MS-MS method has been developed for the quantitative determination of four diterpenoids, dihydrotanshinone I, cryptotanshinone, tanshinone I, and tanshinone IIA in Radix Salviae Miltiorrhizae (RSM, the root of Salvia miltiorrhiza BGE.). The diterpenoids were chromatographically separated on a C18 HPLC column, and the quantification of these diterpenoids was based on the fragments of [M+H]+ under collision-activated conditions and in Selected Reaction Monitoring (SRM) mode. The quantitative method was validated, and the mean recovery rates from fortified samples (n=5) of dihydrotanshinone I, cryptotanshinone, tanshinone I, and tanshinone IIA were 95.0%, 97.2%, 93.1%, and 95.9% with variation coefficient of 6.0%, 4.3%, 3.7%, and 4.2%, respectively. The established method was successfully applied to the quality assessment of seven batches of RSM samples collected from different regions of China.


Assuntos
Diterpenos/química , Diterpenos/isolamento & purificação , Medicamentos de Ervas Chinesas , Raízes de Plantas , Cromatografia Líquida/métodos , Espectrometria de Massas/métodos , Extratos Vegetais , Salvia miltiorrhiza
20.
Chem Pharm Bull (Tokyo) ; 53(5): 481-6, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15863916

RESUMO

This paper describes an improved quality assessment method for Radix Salviae Miltiorrhizae (Root of Salvia miltiorrhiza BGE.) which was established using chromatographic fingerprinting and quantification of multiple marker compounds in the crude drug. High-performance thin-layer chromatography (HPTLC) fingerprinting of water-soluble phenolics and nonpolar tanshinones was performed separately and the authentication of Radix Salviae Miltiorrhizae was achieved by comparing the fingerprints of the samples with those of the reference crude drug and by comparing the Rf values of the bands in TLC fingerprints with those of reference compounds. HPLC fingerprints were obtained by simultaneous separation of phenolics and diterpenoids in Radix Salviae Miltiorrhizae. The HPLC fingerprints of seven batches of samples from different regions of China showed similar chromatographic patterns, and seven peaks were selected as characteristic peaks. The relative retention time of these characteristic peaks in the HPLC fingerprints was established as an important parameter for the identification of this herbal medicine. The pharmacologically active marker compounds salvianolic acid B, rosmarinic acid, and tanshinone IIA in herbal medicine were quantitatively determined using reverse-phase HPLC techniques. The HPLC quantitation methods of the three marker compounds were validated and the measurement uncertainty, which is important for setting the proposed content limit of the marker compounds in herbal medicine, were further evaluated.


Assuntos
Medicamentos de Ervas Chinesas/análise , Medicamentos de Ervas Chinesas/normas , Raízes de Plantas/química , Avaliação Pré-Clínica de Medicamentos/métodos , Avaliação Pré-Clínica de Medicamentos/normas , Extratos Vegetais , Salvia miltiorrhiza
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