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1.
Opt Express ; 32(5): 7307-7317, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38439414

RESUMO

The Fourier single-pixel imaging technique exhibits great potential for compressive imaging. However, the utilization of low sampling ratio can introduce unwanted ringing artifacts, thereby compromising the fidelity of reconstructed image detail. To address this issue, Vector guided Fourier single-pixel imaging (V-FSI) has been proposed. We analyze the statistical properties in the edge vector field derived from images with low sampling ratio. Based on this information, a tailored sampling map is designed to acquire the significant high-frequency components for image reconstruction. Experimental results demonstrate the remarkable effectiveness of the proposed V-FSI method in enhancing image quality. Notably, V-FSI exhibits exceptional capabilities in perceiving and preserving the details of the objects, particularly for objects characterized by pronounced periodicity and directionality.

2.
Appl Opt ; 63(2): 483-491, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38227245

RESUMO

The application field of large forgings is extensive. Accurate dimensional measurement is an important factor to ensure the quality of the finished forging product when it is forged at high temperature. Therefore, this paper proposes a green laser scanning measurement method based on depth information. First, a geometric measurement model based on depth information is established by studying the relationship between green laser depth information and forging dimension. Then, based on the heat transfer theory, distribution of the temperature field around hot forgings is studied, and an error function caused by light refraction is established using a ray tracing algorithm. After that, the error function is used to modify the measurement model to obtain the accurate distance between the forging and background plane and then obtain the dimensional information of the forging. Finally, this measurement method was experimentally verified in the laboratory, and the experimental results show that the measurement error of this method meets the dimensional measurement requirements of large hot forgings.

3.
Crit Rev Food Sci Nutr ; 63(25): 7564-7583, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35253552

RESUMO

Fish sauce is a special flavored condiment formed by traditional fermentation of low-value fish in coastal areas, which are consumed and produced in many parts of the world, especially in Southeast Asia. In the process of fish sauce fermentation, the diversity of microbial flora and the complex metabolic reactions of microorganisms, especially lipid oxidation, carbohydrate fermentation and protein degradation, are accompanied by the formation of flavor substances. However, the precise reaction of microorganisms during the fersmentation process is difficult to accurately control in modern industrial production, which leads to the loss of traditional characteristic flavors in fermented fish sauces. This paper reviews the manufacturing processes, core microorganisms, metabolic characteristics and flavor formation mechanisms of fermented fish sauces at home and abroad. Various methods have been utilized to analyze and characterize the composition and function of microorganisms. Additionally, the potential safety issues of fermented fish sauces and their health benefits are also reviewed. Furthermore, some future directions and prospects of fermented fish sauces are also reviewed in this paper. By comprehensive understanding of this review, it is expected to address the challenges in the modern production of fish sauce thereby expanding its application in food or diet.


Assuntos
Alimentos , Alimentos de Soja , Animais , Fermentação , Dieta
4.
J Anim Physiol Anim Nutr (Berl) ; 107(2): 475-484, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35989475

RESUMO

This study was conducted to evaluate the antioxidant capability of dietary supplementation with monoammonium glycyrrhizinate (MAG) in perinatal cows. Glycyrrhizic acid has been shown to have strong antioxidant activity and we hypothesised that the aglycone of glycyrrhizin and MAG, could reduce damage from oxidative stress in perinatal cows by enhancing antioxidant capacity. Blood and milk samples were collected from three groups of healthy perinatal cows that were similar in body weight, parity, milk yield in the last milk cycle, etc., receiving dietary MAG supplementation ([Day 0 = parturition]: 0 g/day, [n = 13)] 3 g/day [n = 13] or 6 g/day [n = 11]) from -28 to 56 day (0 day = parturition). Compared with 0 g/day controls (CON), milk fat was significantly decreased in cows fed with MAG, and 3 g/day had the greatest effect. A diet containing 3 g/day MAG decreased the serum alanine aminotransferase (ALT) level compared with CON at -7 day post-partum. ALT was also lower at 5 day post-partum in cows fed with 3 g/day MAG compared to 6 g/day. The administration of 3 g/day and 6 g/day MAG decreased serum aspartate transaminase (AST) at 3 day post-partum. Supplementation of MAG in cows increased total antioxidant capacity (T-AOC) in serum, and cows given 3 g MAG per day had higher T-AOC than controls on post-partum 7 day. At the end of the experiment, we isolated and cultured primary hepatocytes to determine the effect of MAG on oxidative stress caused by incubation with the sodium oleate (SO). SO increased lipid synthesis, but pre-treatment with MAG prevented the fatty buildup. SO treatment increased AST and ALT levels and malondialdehyde concentration, but decreased T-AOC and superoxide dismutase (SOD). Incubation with MAG increased antioxidant capacity and inhibited oxidant damage in bovine hepatocytes. SO stimulated expression of the antioxidant genes, NAD(P)H quinone dehydrogenase 1 (NQO1) and SOD1, in the nuclear factor erythroid 2-related factor 2 (NRF2) pathway, and catalase 1 (CAT1); this increase was accentuated by MAG pre-treatment. The results suggest that MAG can alleviate the damage caused by oxidative stress in perinatal cows by enhancing antioxidant activity.


Assuntos
Antioxidantes , Ácido Glicirretínico , Gravidez , Feminino , Bovinos , Animais , Antioxidantes/metabolismo , Ácido Glicirrízico/metabolismo , Ácido Glicirrízico/farmacologia , Estresse Oxidativo , Parto , Dieta/veterinária , Leite/metabolismo , Ácido Glicirretínico/metabolismo , Ácido Glicirretínico/farmacologia , Suplementos Nutricionais , Lactação
5.
Clin Genet ; 101(4): 411-420, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35023146

RESUMO

Elevated serum uric acid (UA) level has been shown to be influenced by multiple genetic variants, but it remains uncertain how UA-associated variants differ in their influence on hyperuricemia risk in people taking antihypertensive drugs. We examined a total of 43 UA-related variants at 29 genes in 1840 patients with hypertension from a community-based longitudinal cohort during a median 2.25-year follow-up (including 1031 participants with normal UA, 440 prevalent hyperuricemia at baseline, and 369 new-onset hyperuricemia). Compared with the wild-type genotypes, patients carrying the SLC2A9 rs3775948G allele or the rs13129697G allele had decreased risk of hyperuricemia, while patients carrying the SLC2A9 rs11722228T allele had increased risk of hyperuricemia, after adjustment for cardiovascular risk factors and correction for multiple comparisons; moreover, these associations were modified by the use of diuretics, ß-blockers, or angiotensin converting enzyme inhibitors. The rs10821905A allele of A1CF gene was associated with increased risk of hyperuricemia, and this risk was enhanced by diuretics use. The studied variants were not observed to confer risk for incident cardiovascular events during the follow-up. In conclusion, the genes SLC2A9 and A1CF may serve as potential genetic markers for hyperuricemia risk in relation to antihypertensive drugs therapy in Chinese hypertensive patients.


Assuntos
Hipertensão , Hiperuricemia , Anti-Hipertensivos/efeitos adversos , Diuréticos/efeitos adversos , Proteínas Facilitadoras de Transporte de Glucose/genética , Humanos , Hipertensão/tratamento farmacológico , Hipertensão/genética , Hiperuricemia/complicações , Hiperuricemia/tratamento farmacológico , Hiperuricemia/genética , Estudos Longitudinais , Fatores de Risco , Ácido Úrico/uso terapêutico
6.
J Cell Physiol ; 236(1): 405-416, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32572960

RESUMO

Epigallocatechin-3-gallate (EGCG) plays a crucial role in hepatic lipid metabolism. However, the underlying regulatory mechanism of hepatic lipid metabolism by EGCG in canine is unclear. Primary canine hepatocytes were treated with EGCG (0.01, 0.1, or 1 µM) and BML-275 (an AMP-activated protein kinase [AMPK] inhibitor) to study the effects of EGCG on the gene and protein expressions associated with AMPK signaling pathway. Data showed that treatment with EGCG had greater activation of AMPK, as well as greater expression levels and transcriptional activity of peroxisome proliferator activated receptor-α (PPARα) along with upregulated messenger RNA (mRNA) abundance and protein abundance of PPARα-target genes. EGCG decreased the expression levels and transcriptional activity of sterol regulatory element-binding protein 1c (SREBP-1c) along with downregulated mRNA abundance and protein abundance of SREBP-1c target genes. Of particular interest, exogenous BML-275 could reduce or eliminate the effects of EGCG on lipid metabolism in canine hepatocytes. Furthermore, the content of triglyceride was significantly decreased in the EGCG-treated groups. These results suggest that EGCG might be a potential agent in preventing high-fat diet-induced lipid accumulation in small animals.


Assuntos
Proteínas Quinases Ativadas por AMP/genética , Catequina/análogos & derivados , Hepatócitos/metabolismo , Metabolismo dos Lipídeos/genética , Transdução de Sinais/genética , Animais , Catequina/genética , Células Cultivadas , Dieta Hiperlipídica , Cães , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Hepatócitos/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , PPAR alfa/genética , Pirazóis/farmacologia , Pirimidinas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Transcrição Gênica/efeitos dos fármacos , Transcrição Gênica/genética , Triglicerídeos/genética , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genética
7.
Clin Exp Hypertens ; 42(1): 8-15, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30563368

RESUMO

Background: Fast resting heart rate (RHR) is easily neglected in clinical practice of hypertension treatment.Aims: We aimed to investigate the prevalence of fast RHR and associated factors in hypertensive and normotensive individuals.Methods: We retrospectively analyzed data from two cross-sectional studies conducted in China. A total of 6763 hypertensive patients and 2807 age and sex-matched normotensive subjects with complete data on resting electrocardiogram and medical history were included. Fast RHR was defined as RHR > 85 bpm.Results: The prevalence of fast RHR was higher in hypertensive patients as compared with the normotensives (14.4% vs 7.1%, P < 0.01). In both hypertensive and normotensive subjects, fast RHR appeared as a "U-type" distribution as aging and a "inverted J type" trend as body mass index (BMI) increasing. Multivariate regression analysis showed that fast RHR was associated with age >65 or <25 years old (OR = 1.32, 95% CI 1.08-1.61), BMI <18.5 kg/m2 (OR = 2.94, 95%CI 1.47-5.87) and hypercholesterolemia (OR = 1.30, 95%CI 1.10-1.53) in hypertensive patients. Fast RHR in the normotensives was associated with female (OR = 1.78, 95%CI 1.27-2.48), pre-hypertensive state (OR = 2.38, 95%CI 1.61-3.52), and rural area origin (OR = 1.50, 95%CI 1.01-2.42). Stroke and diabetes conferred closer relevance to fast RHR in both hypertensive (OR = 1.31, 95%CI 1.02-1.69 and OR 2.26, 95%CI 1.60-3.21) and normotensive individuals (OR = 2.67, 95%CI 1.36-5.21 and OR = 2.77, 95%CI 1.47-5.23).Conclusion: Fast RHR might be common in patients with hypertension. Prior stroke and diabetes history is common associated with fast RHR. Other factors associated with fast RHR seem to be different between hypertensive patients and normotensive subjects.Abbreviations: BMI: body mass index; CI: Confidence Interval; DBP: diastolic blood pressure; ECG: electrocardiogram; OR: odd ratio; RHR: resting heart rate; SBP: systolic blood pressure.


Assuntos
Diabetes Mellitus/fisiopatologia , Frequência Cardíaca , Hipertensão/epidemiologia , Hipertensão/fisiopatologia , Acidente Vascular Cerebral/fisiopatologia , Adulto , Fatores Etários , Idoso , Pressão Sanguínea , Estudos de Casos e Controles , China/epidemiologia , Comorbidade , Estudos Transversais , Diabetes Mellitus/epidemiologia , Eletrocardiografia , Feminino , Humanos , Hipercolesterolemia/epidemiologia , Hipercolesterolemia/fisiopatologia , Masculino , Pessoa de Meia-Idade , Pré-Hipertensão/epidemiologia , Pré-Hipertensão/fisiopatologia , Prevalência , Descanso/fisiologia , Estudos Retrospectivos , População Rural/estatística & dados numéricos , Fatores Sexuais , Acidente Vascular Cerebral/epidemiologia
8.
Biol Proced Online ; 21: 17, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31496923

RESUMO

BACKGROUND: The presence of residual DNA carried by biological products in the body may lead to an increased oncogenicity, infectivity, and immunomodulatory risk. Therefore, current agencies including WHO, EU, and the FDA limited the accepted amounts of residual DNA (less than 10 ng or 100 pg/dose). Among the methods of detecting residual DNA, qPCR is considered to be the most practical for residual DNA quantitation due to its sensitivity, accuracy, precision, and time-saving. RESULTS: In this study, the detection capacity of this method was determined by comparing the detected concentration of the commercial kit and the self-designed primer/probe set after the same treatment of the extraction method. Then, a universal sample pretreatment method based on a co-precipitant was optimized. The validation results demonstrated that the method has appropriate specificity, sensitivity, accuracy, and precision according to ICH guidelines. The limit of detection and quantitation reached 3 fg/ul and 0.3 pg/reaction respectively, which satisfies the requirement of limit of residual DNA detection in biologics. Spike recovery (82.3-105.7%) showed that the proposed qPCR assay was accurate and has good extraction efficiency. Moreover, the precision of the method based on intra- and inter-assay was 0.065-0.452% and 0.471-1.312%, respectively. CONCLUSIONS: These results all indicated that the method for determination of residual DNA in biological products expressed from CHO cells is sensitive, accurate and robust.

9.
Acta Neurol Scand ; 140(1): 78-83, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31002173

RESUMO

OBJECTIVES: Lacunar stroke had an unfavorable prognosis in the long term with a high risk of recurrent stroke, aspirin has been widely used to prevent ischemic stroke, but data on the effect of antiplatelet therapy on lacunar infarction are limited. We investigated the long-term effect of aspirin treatment on stroke recurrence risk in patients with lacunar stroke in a multicenter prospective cohort. METHODS: Between November 2000 and November 2001, 2000 consecutive stroke patients (age 35-74 years) were recruited from seven clinical centers. For the present study, a total of 544 patients with lacunar infarction were finally included in the analysis. The patients were divided into two groups (aspirin group, n = 342 and non-aspirin group, n = 202).The effect of aspirin on stroke recurrence was evaluated by using Kaplan-Meier analysis and Cox regression models. RESULTS: During a median 4.1-year follow-up for 544 patients with lacunar stroke, 99 recurrent strokes, 125 major vascular events (stroke, myocardial infarction, and vascular death), 31 vascular deaths, and 59 all-cause deaths were identified. Kaplan-Meier analysis showed that aspirin non-users had a higher risk of future recurrent stroke and of vascular events than did aspirin users (log-rank test, P = 0.049, 0.047, respectively). Aspirin significantly reduced the stroke recurrence in patients with lacunar stroke analyzed with multivariate stepwise analysis using model of Cox proportional hazards with backward elimination (HR = 0.67, 95% CI 0.45-0.99). CONCLUSION: We concluded that aspirin significantly reduced stroke recurrence in patients with lacunar stroke.


Assuntos
Aspirina/uso terapêutico , Inibidores da Agregação Plaquetária/uso terapêutico , Acidente Vascular Cerebral Lacunar/prevenção & controle , Adulto , Idoso , Estudos de Coortes , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Prognóstico , Modelos de Riscos Proporcionais , Estudos Prospectivos , Recidiva
10.
J Aging Soc Policy ; 31(3): 271-290, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-29979945

RESUMO

Facing a rapidly aging population, China has recently started to formulate and implement policies with the aim to provide old-age care. While well-developed old-age care policies commonly include a built-in component that assesses eligibility based on vulnerability, no such process is established in the context of China. Here, based on data from the China Health and Retirement Longitudinal Study collected in both 2011 and 2013, we (a) developed a simple and effective strategy for identifying vulnerable Chinese elderly, which can serve as a basis for policy targeting, and (b) improved the policy relevance and targeting efficiency of this vulnerability measure by including additional health indicators. Our vulnerability measures identify 35% to 46% of Chinese elderly as vulnerable, covering up to 67% of elderly at high risk of death or functional decline. They can serve as an initial screening step for more comprehensive geriatric assessments and enable policy makers to effectively target vulnerable elderly persons in China.


Assuntos
Envelhecimento , Avaliação Geriátrica/métodos , Política de Saúde , Populações Vulneráveis , Atividades Cotidianas , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/fisiologia , Envelhecimento/psicologia , China , Feminino , Serviços de Saúde para Idosos , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Curva ROC , Aposentadoria , Inquéritos e Questionários
12.
Langmuir ; 34(46): 14076-14084, 2018 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-30372624

RESUMO

A syndiotactic-rich PHEMA oligomer ( rr = 74%, DP = 29, PDI = 1.19) was synthesized and subsequently subjected to self-assembly with a varying amount of γ-CDs in its aqueous solution to create mismatched overfit polypseudorotaxanes (PPRs). The inclusion complexation proceeded in an obvious mismatched manner between the cavity of γ-CDs and the cross-sectional area of an incoming PHEMA chain. The 2D-NOESY NMR analysis provided direct evidence indicating that two adjacent pendant hydroxyethyl groups in PHEMA preferably adopt a curled conformation to pass through the cavity of γ-CDs, giving the PPRs characteristics of a mismatched overfit instead of a matched tight-fit crystal structure. The results suggested that the mutual adaption of pendant side chains of HEMA units with the cavity geometry of γ-CDs would play a dominant role in this unfavorable overfit inclusion complexation besides the size of γ-CDs and the stereoregularity of the PHEMA chain.

13.
J Vet Pharmacol Ther ; 41(6): 919-923, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30043978

RESUMO

As a semisynthetic tetracycline derivative, doxycycline (α-6-deoxy-5-hydroxytetracycline) is a time-dependent bacteriostatic agent. It is being widely used in the broiler husbandry in China. In this study, doxycycline was orally administered by gavage to 10 healthy broiler chickens at the dose of 20 mg/kg body weight every 24 hr for five total treatments. Plasma samples were collected from each animal at 5, 10, 20, and 30 min and 1, 2, 4, 6, 8, and 12 hr after the first dose, at 0.25, 0.5, 0.45, 1, 2, 3, 4, 6, 7, 13.5, 24, 36, 48, 60, and 72 hr after the last dose. Additional plasma samples were collected at a 24-hr interval during the dosing period (immediately prior to each oral administration). The doxycycline concentrations were determined by high-performance liquid chromatography with an ultraviolet detector and subjected to noncompartmental analysis. Then, the pharmacokinetics profiles were compared after the first and last oral doses. After the first dosing, the elimination half-life, area under the concentration-time curve from 0 hr to ∞, peak concentration, time to reach peak concentration, and volume of distribution per fraction absorbed were determined as 7.78 hr, 94.19 µg·hr/ml, 5.65 µg/ml, 3.50 hr, and 2,502.65 ml/kg, respectively, while the corresponding values of these parameters after the last dose were 19.90 hr, 121.08 µg·hr/ml, 5.71 µg/ml, 7.25 hr, and 5,285.28 ml/kg, respectively. After multiple oral doses, the absorption and elimination both became slower, while the distribution was more extensive than that following a single dose. However, after multiple oral doses, accumulation of doxycycline in plasma was not observed with an average accumulation factor of 1.11.


Assuntos
Antibacterianos/farmacocinética , Galinhas/sangue , Doxiciclina/farmacocinética , Administração Oral , Animais , Antibacterianos/administração & dosagem , Área Sob a Curva , Disponibilidade Biológica , Doxiciclina/administração & dosagem , Esquema de Medicação , Meia-Vida , Distribuição Tecidual
14.
J Vet Pharmacol Ther ; 41(5): 739-745, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29892973

RESUMO

The pharmacokinetic profiles of florfenicol (FF) or florfenicol amine (FFA) in crucian carp were compared at different water temperatures after single intramuscular administration of FF at 10 mg/kg bodyweight. The concentrations of FF and FFA were determined by a high-performance liquid chromatography method, and then, the concentration versus time data were subjected to compartmental analysis using a one-compartment open model. At the water temperatures of 10, 20, and 25°C, the peak concentrations (Cmax s) of FF were 2.28, 2.29, and 2.34 µg/ml, respectively, while those of FFA were 0.42, 0.71, and 0.82 µg/ml, respectively. And the absorption half-life (t1/2ka ) of FF was 0.21, 0.19, and 0.21 hr, while the elimination half-life (t1/2kel ) was 31.66, 24.77, and 21.48 hr, respectively. For FFA, the formation half-life (t1/2kf ) was 3.85, 8.97, and 12.43 hr, while the t1/2kel was 58.34, 30.27, and 21.22 hr, respectively. The results presented here demonstrated that the water temperature had effects on the elimination of both FF and FFA and the formation of FFA. Based on the T > MIC values calculated here, to treat the infections of bacterial with MIC value ≤ 0.5 µg/ml, FF intramuscularly given at 10 mg/kg bodyweight with a 72-hr interval is sufficient at the water temperature of 10°C, while the intervals of 60 and 48 hr were needed at 20 and 25°C, respectively. But to treat bacterial with higher MIC values, more FF or FF at 10 mg/kg BW but with shorter intervals should be intramuscularly given to the infected fish.


Assuntos
Antibacterianos/farmacocinética , Tianfenicol/análogos & derivados , Animais , Antibacterianos/administração & dosagem , Antibacterianos/sangue , Cromatografia Líquida de Alta Pressão/veterinária , Carpa Dourada/sangue , Carpa Dourada/metabolismo , Injeções Intramusculares/veterinária , Temperatura , Tianfenicol/administração & dosagem , Tianfenicol/sangue , Tianfenicol/farmacocinética
15.
Anal Chem ; 87(21): 10822-9, 2015 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-26451797

RESUMO

MicroRNAs (miRNAs), critical biomarkers of acute and chronic diseases, play key regulatory roles in many biological processes. As a result, there is great demand for robust assay platforms to enable an accurate and efficient detection of low-level miRNAs in complex biological samples. In this work, a label-free and Au nanoparticles (NPs) quenching-based competition assay system was developed. In the designed system, Au NPs with diameter sizes of 10 and 20 nm displayed fluorescence quenching efficiencies of 84% and 82% for Cy3 dye on slide surface, whereas the quenching efficiency of commercial BHQ2 quencher was roughly 50%. Assay conditions were optimized for miRNA-205 detection. A limit of detection of 3.8 pM and a detection range covering from 3.8 pM to 10 nM were achieved. Furthermore, the proposed system was capable of specifically discriminating miRNAs with slight variations in their nucleotide sequence and was also qualified for assessing miRNA levels in human serum. Our strategy has the potential to provide new perspectives in profiling the pattern of miRNA expression and biomedical utilizations.


Assuntos
Bioensaio/métodos , Ouro/química , MicroRNAs/análise , Nanopartículas/química , Fluorescência , Humanos , Limite de Detecção , MicroRNAs/química , Hibridização de Ácido Nucleico , Coloração e Rotulagem
16.
Beilstein J Org Chem ; 11: 2267-77, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26732122

RESUMO

Pentablock copolymers PMA-PPO-PEO-PPO-PMA synthesized via atom transfer radical polymerization (ATRP) were self-assembled with varying amounts of γ-CDs to prepare poly(pseudorotaxanes) (PPRs). When the concentration of γ-CDs was lower, the central PEO segment served as a shell of the micelles and was preferentially bent to pass through the γ-CD cavity to construct double-chain-stranded tight-fit PPRs characterized by a channel-like crystal structure. With an increase in the amount of γ-CDs added, they began to accommodate the poly(methyl acrylate) (PMA) segments dissociated from the core of the micelles. When more γ-CDs were threaded and slipped over the segments, the γ-CDs were randomly distributed along the pentablock copolymer chain to generate single-chain-stranded loose-fit PPRs and showed no characteristic channel-like crystal structure. All the self-assembly processes of the pentablock copolymers resulted in the formation of hydrogels. After endcapping via in situ ATRP of 2-methacryloyloxyethyl phosphorylcholine (MPC), these single-chain-stranded loose-fit PPRs were transformed into conformational identical polyrotaxanes (PRs). The structures of the PPRs and PRs were characterized by means of (1)H NMR, GPC, (13)C CP/MAS NMR, 2D (1)H NOESY NMR, FTIR, WXRD, TGA and DSC analyses.

17.
Pak J Pharm Sci ; 27(4 Suppl): 1069-74, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25016268

RESUMO

Residue after evaporation (RAE) from industrial vitamin C fermentation is emitted as a waste product at an amount of 60,000 tons per year in China. The disposal of RAE is difficult because of its high chemical oxygen demand (1.17×10(6) mg/l) and low pH (0.27). We hypothesized that RAE could be used as an ameliorant for alkali-saline soils, and tried to verify it by carrying out a pot experiment of pakchoi cultivation and to explore its effect on soil chemical and microbial properties. The results showed that pakchoi yield was increased by 28.13% and pakchoi quality was also enhanced under RAE treatment. The improved chemical and microbial properties of treated soil were also observed: soil pH was decreased from 9.19 to 9.03; total organic carbon, available phosphorus and available potassium were increased by 49.15%, 34.91% and 42.02%, respectively; number of culturable bacteria, actinomycetes and fungi, microbial biomass carbon and enzyme activity number were improved by 52.97%, 104.05%, 79.09%, 57.82% and 31.16%, respectively. These results suggested the residue application led to an improved soil quality and subsequently a higher yield and quality of pakchoi. This study provided a strong evidence for the feasibility of RAE as an ameliorant for alkali-saline soil.


Assuntos
Ácido Ascórbico/metabolismo , Fermentação , Resíduos Industriais , Microbiologia do Solo , Solo/química , Álcalis , Volatilização
18.
Beilstein J Org Chem ; 10: 2461-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25383117

RESUMO

A pentablock copolymer was prepared via the atom transfer radical polymerization of 2-hydroxyethyl methacrylate (HEMA) initiated by 2-bromoisobutyryl end-capped PPO-PEO-PPO as a macroinitiator in DMF. Attaching PHEMA blocks altered the self-assembly process of the pentablock copolymer with γ-CDs in aqueous solution. Before attaching the PHEMA, the macroinitiator was preferentially bent to pass through the inner cavity of γ-CDs to give rise to tight-fit double-chain stranded polypseudorotaxanes (PPRs). After attaching the PHEMA, the resulting pentablock copolymer was single-chain stranded into the interior of γ-CDs to form more stable, loose-fit PPRs. The results of (1)H NMR, WXRD, DSC, TGA, (13)C CP/MAS NMR and FTIR analyses indicated that γ-CDs can accommodate and slip over PHEMA blocks to randomly distribute along the entire pentablock copolymer chain. This results in unique, single-chain stranded PPRs showing no characteristic channel-type crystal structure.

19.
Artigo em Inglês | MEDLINE | ID: mdl-38973513

RESUMO

BACKGROUND: Patients with cirrhosis commonly undergo endoscopic cyanoacrylate injection for gastric and esophageal variceal bleeding. However, postoperative infections can increase the risk of rebleeding and mortality. AIM: This study aimed to determine the risk of postoperative infections and its associated factors following cyanoacrylate injection treatment in these patients. METHODS: A retrospective analysis was conducted on 57 patients treated with ligation (ligation group), 66 patients treated with cyanoacrylate injection (injection group), and 91 patients treated with conservative treatment (control group) at the Nanchong Central Hospital. RESULTS: The rate of postoperative infection was similar among the cyanoacrylate, ligation, and conservative treatment groups, with no significant statistical difference observed (P = 0.97). Multivariate analysis identified postoperative Child-Pugh score and renal insufficiency as two independent risk factors for postoperative infection. The rebleeding rate in the injection group was significantly lower than in the other groups (P = 0.01). Mortality was significantly higher in the control group compared with the ligation and injection groups (P = 0.01). CONCLUSION: Cyanoacrylate combined with lauromacrogol injection did not significantly increase the risk of infection compared with ligation and conservative treatments, and it was more effective in reducing the risk of rebleeding. This method is safe, effective, and holds clinical value for broader application.

20.
Mycopathologia ; 176(3-4): 255-8, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23912467

RESUMO

Scutula are characteristic lesions of tinea favosa or favus; the most frequently identified causative organism is Trichophyton schoenleinii. Although scutula-like lesions were described in Microsporum gypseum infection, their presence on glabrous skin in a patient with SLE has not been reported previously. We report a case of tinea infection with scutula-like lesions caused by Microsporum gypseum in a SLE patient, who was treated with topical terbinafine cream, and the lesions resolved completely. In addition, we reviewed the reported cases about this rare clinical manifestation caused by Microsporum gypseum in the medical literature.


Assuntos
Microsporum/isolamento & purificação , Pele/patologia , Tinha/diagnóstico , Tinha/patologia , Administração Tópica , Adolescente , Antifúngicos/administração & dosagem , Feminino , Humanos , Lúpus Eritematoso Sistêmico/complicações , Naftalenos/administração & dosagem , Terbinafina , Tinha/microbiologia , Resultado do Tratamento
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