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1.
Biomacromolecules ; 25(3): 1923-1932, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38394470

RESUMO

Fatty acid cellulose esters (FACE) are common cellulose-based thermoplastics, and their thermoplasticity is determined by both the contents and the lengths of the side chains. Herein, various FACE were synthesized by the ball-milling esterification of cellulose and fatty acyl chlorides containing 10-18 carbons, and their structures and thermoplasticity were thoroughly studied. The results showed that FACE with high degrees of substitution (DS) and low melting flow temperatures (Tf) were achieved as the chain lengths of the fatty acyl chlorides were reduced. In particular, a cellulose decanoate with a DS of 1.85 and a Tf of 186 °C was achieved by feeding 3 mol of decanoyl chloride per mole anhydroglucose units of cellulose. However, cellulose stearate (DS = 1.53) synthesized by the same protocols cannot melt even at 250 °C. More interestingly, the fatty acyl chlorides with 10 and 12 carbons resulted in FACE with superior toughness (elongation at break up to 94.4%). In contrast, due to their potential crystallization of the fatty acyl groups with 14-18 carbons, the corresponding FACE showed higher tensile strength and Young's modulus than the others. This study provides some theoretical basis for the mechanochemical synthesis of thermoplastic FACE with designated properties.


Assuntos
Cloretos , Ésteres , Ésteres/química , Estudos de Viabilidade , Esterificação , Celulose/química
2.
Zhongguo Zhong Yao Za Zhi ; 44(7): 1403-1409, 2019 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-31090298

RESUMO

The qualitative analysis of flavonoids in Coreopsis tinctoria was carried out by a combination of 2 D-TLC and HPLC-IT-TOF-MS. The separation was conducted on 2 D-TLC and a Phenomenex Kinetex Evo C_(18) column(2.1 mm×100 mm, 2.6 µm) with methanol-0.05% aqueous formic acid by gradient elution. Electrospray ionization-(ESI) source was applied and operated in both positive and negative ionization modes. Eighteen flavonoids including three flavonoids, one flavonol, nine flavonones, one flavanonol and four chalcones, were putatively identified from the flavone-enriched fraction of C. tinctoria. 2 D-TLC could separate the flavonoids from C. tinctoria. HPLC-IT-TOF-MS was able to quickly and accurately analyze the flavonoids in C. tinctoria. The results would provide experimental information for the efficacy material basis clarification of C. tinctoria.


Assuntos
Coreopsis/química , Flavonoides/análise , Extratos Vegetais/análise , Chalconas/análise , Cromatografia Líquida de Alta Pressão , Compostos Fitoquímicos/análise , Espectrometria de Massas por Ionização por Electrospray
3.
Carbohydr Polym ; 168: 301-309, 2017 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-28457453

RESUMO

The goal of present study was to investigate the structural dependence of chitosan derivatives on enantioseparation and mobile phase tolerance of the corresponding chiral packing materials for liquid chromatography. Hence, a series of chitosan bis(arylcarbamate)-(n-pentyl amide)s and the related chiral stationary phases (CSPs) were prepared from chitosans with different molecular weights. Because of the H-bond formed via CH3-π interaction, the CSP bearing methyl substituent exhibited high tolerance than the ones bearing dichloro substituents. The CSP derived from the chitosan bis(3,5-dichlorophenylcarbamate)-(n-pentyl amide) with a higher molecular weight possessed high tolerance to mobile phases, whereas the enantioseparation capability of this CSP was not as good as that of the one prepared from the chitosan derivative with a lower molecular weight. Therefore, enantioseparation capability and mobile phase tolerance have to be counterbalanced in designing chiral selectors for the CSPs derived from chitosan bis(arylcarbamate)-(amide)s.

4.
Psychol Health Med ; 22(1): 94-109, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-26853191

RESUMO

Breast cancer (BC) patients in China suffered from a variety of psychology stress such as perceived stress and anxiety, posttraumatic growth (PTG) as a positive factor could promote their psychology health and quality of life. This study aimed to investigate the efficacy of mindfulness-based stress reduction (MBSR) on promoting PTG, decreasing perceived stress and anxiety of Chinese BC patients. A randomized controlled trial of 60 BC patients (Stages I-III) was conducted. They were randomly divided to the 8-week MBSR group or usual care (UC) group. PTG inventory, Perceived Stress Scale of Chinese version (CPSS) and State Trait Anxiety Inventory (STAI) evaluated the PTG level, perceived stress and anxiety at three times(before intervention-T1, after intervention-T2 and follow up at 3 months-T3). A repeated-measures analysis of variance model was used to compare each outcome measure of two groups at the three times. There was one patient discontinued the intervention and one lose to follow up in MBSR group, finally 58 BC patients completed the research. There was no difference between two groups before the intervention. The results showed significant improvements in MBSR group comparing with the UC group that PTG level was much higher after the 8-week intervention and the follow up (F = 34.73, p < .00). At the same time, CPSS (F = 14.41, p < .00) and STAI (F = 15.24, p < .00) scores were significant decreased at T2 and T3. The results showed that MBSR promoted the level of PTG and decreased perceived stress and anxiety state of Chinese BC patients, and the results persisted at three months after intervention. The research preliminary proved that MBSR was suitable to Chinese BC patients. MBSR should be recommending to BC survivors in China.


Assuntos
Neoplasias da Mama/psicologia , Sobreviventes de Câncer/psicologia , Atenção Plena/métodos , Avaliação de Resultados em Cuidados de Saúde , Estresse Psicológico/terapia , Adulto , China , Feminino , Humanos , Pessoa de Meia-Idade
5.
Molecules ; 21(11)2016 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-27801845

RESUMO

Penicitroamide (1), a new metabolite with a new framework, was isolated from the ethyl acetate extract of the PDB (Potato Dextrose Broth) medium of Penicillium sp. (NO. 24). The endophytic fungus Penicillium sp. (NO. 24) was obtained from the healthy leaves of Tapiscia sinensis Oliv. The structure of penicitroamide (1) features a bicyclo[3.2.1]octane core unit with a high degree of carbonylization (four carbonyl groups and one enol group). The chemical structure of penicitroamide (1) was elucidated by analysis of 1D-, 2D-NMR and MS data. In bioassays, penicitroamide (1) displayed antibacterial potency against two plant pathogens, Erwinia carotovora subsp. Carotovora (Jones) Bersey, et al. and Sclerotium rolfsii Sacc. with MIC50 at 45 and 50 µg/mL. Compound 1 also showed 60% lethality against brine shrimp at 10 µg/mL. Penicitroamide (1) exhibited no significant activity against A549, Caski, HepG2 and MCF-7 cells with IC50 > 50 µg/mL. Finally, the possible biosynthetic pathway of penicitroamide (1) was discussed.


Assuntos
Anti-Infecciosos/isolamento & purificação , Anti-Infecciosos/farmacologia , Compostos Heterocíclicos com 3 Anéis/isolamento & purificação , Compostos Heterocíclicos com 3 Anéis/farmacologia , Penicillium/química , Agaricales/efeitos dos fármacos , Animais , Anti-Infecciosos/química , Anti-Infecciosos/toxicidade , Artemia/efeitos dos fármacos , Carbono/química , Erwinia/efeitos dos fármacos , Compostos Heterocíclicos com 3 Anéis/química , Compostos Heterocíclicos com 3 Anéis/toxicidade , Humanos , Células MCF-7 , Magnoliopsida/microbiologia , Testes de Sensibilidade Microbiana , Estrutura Molecular , Folhas de Planta/microbiologia , Testes de Toxicidade
6.
J Sep Sci ; 39(19): 3728-3735, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27514503

RESUMO

Highly N-deacetylated chitosan was chosen as a natural chiral origin for the synthesis of the selectors of chiral stationary phases. Therefore, chitosan was firstly acylated by various alkyl chloroformates yielding chitosan alkoxyformamides, and then these resulting products were further derivatized with 4-methylphenyl isocyanate to afford chitosan bis(4-methylphenylcarbamate)-(alkoxyformamide). A series of chiral stationary phases was prepared by coating these derivatives on 3-aminopropyl silica gel. The content of the derivatives on the chiral stationary phases was nearly 20% by weight. The chiral stationary phases prepared from chitosan bis(4-methylphenylcarbamate)-(ethoxyformamide) and chitosan bis(4-methylphenylcarbamate)-(isopropoxyformamide) comparatively showed better enantioseparation capability than those prepared from chitosan bis(4-methylphenylcarbamate)-(n-pentoxyformamide) and chitosan bis(4-methylphenylcarbamate)-(benzoxyformamide). The tolerance against organic solvents of the chiral stationary phase of chitosan bis(4-methylphenylcarbamate)-(ethoxyformamide) was investigated, and the results revealed that this phase can work in 100% ethyl acetate and 100% chloroform mobile phases. Because as-synthesized chiral selectors did not dissolve in many common organic solvents, the corresponding chiral stationary phases can be utilized in a wider range of mobile phases in comparison with conventional coating type chiral stationary phases of cellulose and amylose derivatives.

7.
Zhonghua Nan Ke Xue ; 20(8): 706-8, 2014 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-25195366

RESUMO

OBJECTIVE: To evaluate the impacts of three different surgical approaches to urethral stricture on the erectile function of the patients. METHODS: This study included 126 male patients with urethral stricture, 35 treated by substitution urethroplasty (group A), 52 by anastomotic urethroplasty (group B), and 39 by internal urethroplasty (group C). We evaluated the pre- and postoperative erectile function of the patients using IIEF-5 scores by telephone calls and interviews. We also monitored their nocturnal penile tumescence (NPT). RESULTS: The IIEF-5 scores in groups A, B and C were 13.5 +/- 4.5, 11.1 +/- 4.8 and 14.5 +/- 4.41 respectively after surgery, all significantly decreased as compared with 17.1 +/- 2.6, 17.1 +/- 3.0 and 17.6 +/- 2.2 preoperatively (P < 0.05). CONCLUSION: All the three surgical approaches can reduce IIEF-5 scores in patients with urethral stricture, but anastomotic urethroplasty may induce a higher incidence of erectile dysfunction than the other two approaches.


Assuntos
Ereção Peniana/fisiologia , Estreitamento Uretral/cirurgia , Procedimentos Cirúrgicos Urológicos Masculinos/métodos , Adulto , Idoso , Humanos , Período Intraoperatório , Masculino , Pessoa de Meia-Idade , Adulto Jovem
8.
Clin Invest Med ; 34(6): E358, 2011 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-22129926

RESUMO

PURPOSE: The prognostic efficiency of clinical grading and staging in patients with confined or moderately differentiated prostate cancer (PCa) has been markedly improved, which underscores the importance of new prognostic markers. Extracellular matrix metalloproteinase inducer (EMMPRIN) has been demonstrated to be involved in cancerangiogenesis, metastasis and invasion. EMMPRIN expression was evaluated by measuring mRNA and protein levels in a large cohort of patients with PCa following prostatectomy and the findings were compared with clinico-pathological parameters, including prostate-specific antigen (PSA) relapse time. METHODS: EMMPRIN mRNA levels in 20 pairs of normal and cancerous prostate tissues were determined by quantitative real-time PCR. Protein expression in paraffin-embedded specimens of prostates gathered from 300 patients with PCa was detected by immunohistochemistry using a monoclonal antibody against EMMPRIN. The associations of EMMPRIN protein expression with the clinico-pathological parameters and PSA relapse-free time after radical prostatectomy were subsequently assessed. RESULTS: Both EMMPRIN mRNA and protein levels were higher in PCa tissue, compared with adjacent normal tissue. In addition, the positive expression rates of EMMPRIN in PCa tissues were significantly associated with preoperative PSA levels (p=0.008), AJCC stage (p=0.006) and Gleason Score (p < 0.001), Risk classification (p < 0.001), lymph node status post-surgery (p < 0.001) and surgical margin status (p < 0.001) were also determined. Multivariate analysis, using the Cox proportional hazards model, revealed that positive EMMPRIN expression was an independent prognostic factor for an increased risk of PSA relapse. CONCLUSION: Over-expression of EMMPRIN correlated with the aggressiveness of PCa, and the PSA relapse-free time, and may be a novel and useful biomarker for follow-up and treatment decisions for PCa.


Assuntos
Basigina/metabolismo , Antígeno Prostático Específico/metabolismo , Prostatectomia/métodos , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/cirurgia , Idoso , Basigina/genética , Indução Enzimática , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Antígeno Prostático Específico/genética , Neoplasias da Próstata/patologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real
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