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1.
Langmuir ; 38(1): 422-429, 2022 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-34962810

RESUMEN

Multi-stimuli-responsive Janus composite nanoparticles (JNPs) of poly(N-isopropylacrylamide)-Fe3O4-poly(2-(dimethylamino)ethyl methacrylate)) (PNIPAM-Fe3O4-PDMEAMA) are synthesized by sequential reversible addition-fragmentation chain-transfer grafting of the polymer PNIPAM and atom-transfer radical polymerization grafting of the polymer PDMEAMA from the corresponding sides of modified Fe3O4 nanoparticles of ∼10 nm size. The hydrophilic/amphiphilic/hydrophobic reversible transition of the JNP can be triggered by pH and temperature since the wettability of the two polymers on the opposite sides is tunable accordingly. At a high pH value and a low surrounding temperature, applying near-infrared irradiation will induce the amphiphilic/hydrophobic transition owing to the photothermal effect of Fe3O4 NPs. The JNP can serve as a responsive solid emulsifier, and the stability and microstructure of the emulsions can be easily controlled by external stimuli such as the pH, temperature, and magnetic field.

2.
J Biochem Mol Toxicol ; 29(4): 189-97, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25530438

RESUMEN

Gap junction intercellular communication is involved in ischemia-reperfusion (IR) injury of organs. Connexins are proteins that are critical to the function of gap junctions. To clarify the role of gap junctions in IR injury in liver cells, the function of gap junctions was modulated in an in vitro hypoxia/reoxygenation (H/R) model. BRL-3A rat liver cells, endogenously expressing connexins Cx32 and Cx43, were used to model the process of hepatic IR injury. Suppression of gap junction activity was achieved genetically, using Cx32-specific small interfering RNA (siRNA), or chemically, with pharmacological inhibitors, oleamide, and 18-α-GA. BRL-3A cells subjected to H/R exhibited reduced cell survival and pathologies indicative of IR injury. Cx32-specific siRNA, oleamide, and 18-α-GA, respectively, decreased gap junction permeability, as assessed by the parachute assay. Pretreatment with Cx32-specific siRNA increased cell survival. Pretreatment with oleamide or 18-α-GA did not improve cell survival. Modulating gap junction by Cx32 gene silencing protected BRL-3A liver cells from H/R.


Asunto(s)
Conexinas/antagonistas & inhibidores , Interferencia de ARN , Daño por Reperfusión/terapia , Animales , Línea Celular , Conexinas/genética , Conexinas/metabolismo , Regulación hacia Abajo , Uniones Comunicantes/efectos de los fármacos , Expresión Génica , Hepatocitos/efectos de los fármacos , ARN Interferente Pequeño , Ratas , Proteína beta1 de Unión Comunicante
3.
J Agric Food Chem ; 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38835142

RESUMEN

The escalating global consumption of tetracyclines (TCs) as broad-spectrum antibiotics necessitates innovative approaches to mitigate their pervasive environmental persistence and associated risks. While initiatives such as China's antimicrobial reduction efforts highlight the urgency of responsible TC usage, the need for efficient degradation methods remains paramount. Microbial degradation emerges as a promising solution, offering novel insights into degradation pathways and mechanisms. Despite challenges, including the optimization of microbial activity conditions and the risk of antibiotic resistance development, microbial degradation showcases significant innovation in its cost-effectiveness, environmental friendliness, and simplicity of implementation compared to traditional degradation methods. While the published reviews have summarized some aspects of biodegradation of TCs, a systematic and comprehensive summary of all the TC biodegradation pathways, reactions, intermediates, and final products including ring-opening products involved with enzymes and mechanisms of each bacterium and fungus reported is necessary. This review aims to fill the current gap in the literature by offering a thorough and systematic overview of the structure, bioactivity mechanism, detection methods, microbial degradation pathways, and molecular mechanisms of all tetracycline antibiotics in various microorganisms. It comprehensively collects and analyzes data on the microbial degradation pathways, including bacteria and fungi, intermediate and final products, ring-opening products, product toxicity, and the degradation mechanisms for all tetracyclines. Additionally, it points out future directions for the discovery of degradation-related genes/enzymes and microbial resources that can effectively degrade tetracyclines. This review is expected to contribute to advancing knowledge in this field and promoting the development of sustainable remediation strategies for contaminated environments.

4.
Front Vet Sci ; 11: 1468981, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39205805

RESUMEN

The porcine reproductive and respiratory syndrome virus (PRRSV) is a highly significant infectious disease that poses a substantial threat to the global pig industry. In recent years, the NADC30-like strain has gradually emerged as prevalent in China, causing a profound impact on the country's pig farming industry. Therefore, it is important to conduct an in-depth study on the characteristics and gene functions of the NADC30-like strain. An infectious cDNA clone is an indispensable tool for investigating the functions of viral genes. In this current study, we successfully isolated a NADC30-like strain and constructed its full-length infectious cDNA clone. The utilization of this clone will facilitate our investigation into the viral replication, pathogenesis, and immune response associated with the PRRSV NADC30-like strain.

5.
Int J Ophthalmol ; 15(4): 533-540, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35450190

RESUMEN

AIM: To investigate the effects of baffle and intraocular pressure (IOP) on the aerosols generated in the noncontact tonometer (NCT) measurement and provide recommendations for the standardized use of the NCT during coronavirus disease 2019 (COVID-19). METHODS: This clinical trial included 252 subjects (312 eyes) in The Eye Hospital, Wenzhou Medical University from March 7, 2020, to March 28, 2020. Sixty subjects (120 eyes) with normal IOP were divided into two groups. One group used an NCT without a baffle, another group used an NCT with a baffle. Another 192 subjects (192 eyes) were divided into four groups: Group A1 (without a baffle+normal IOP), Group A2 (without a baffle+high IOP), Group B1 (with a baffle+normal IOP) and Group B2 (with a baffle+high IOP). Particulate matter (PM) 2.5 and PM10 generated by all subjects were quantified during the NCT measurement. The IOP values were recorded simultaneously. Effects of baffle and IOP on aerosols generated during the NCT measurement were analyzed. RESULTS: In the normal eye group with a baffle, the aerosol density decreased in a wave-like shape near the NCT with the increase in the number of people measured for IOP, demonstrating no cumulative effect. However, in the normal eye group without a baffle, there was a cumulative effect. PM2.5 and PM10 in Group A2 were higher than Group A1 (both P<0.001). The PM2.5 and PM10 in Group B2 were higher than Group B1 (P<0.01, P<0.001 respectively). The PM10 of Group B1 was lower than Group A1 (P<0.01). PM2.5 in Group B2 were lower than Group A2 (P<0.01). The median of per capita PM2.5 and PM10 in the combined Group A1+A2 were 0.80 and 1.10 µg/m3 respectively, which were higher than 0.20 and 0.60 µg/m3 in the combined Group B1+B2 (both P<0.01). The median of per capita PM2.5 and PM10 in the combined Group A1+B1 were 0.10 and 0.20 µg/m3 respectively, which were lower than 1.30 and 1.70 µg/m3 in the combined Group A2+B2 (both P<0.001). CONCLUSION: More aerosols could be generated in patients with high IOP. After the NCT is equipped with a baffle, per capita aerosol density generated decreased significantly near the NCT; And with the increase in the number of people measured for IOP, the aerosols gradually dissipated near the NCT, demonstrating no cumulative effect. Therefore, it is suggested that the NCT should be equipped with a baffle, especially for patients with high IOP.

6.
Int J Gen Med ; 14: 687-695, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33688240

RESUMEN

BACKGROUND AND OBJECTIVES: Serum uric acid (sUA) level has been reported to be associated with arteriosclerotic cardiovascular risk, yet remains poorly defined in Chinese type 2 diabetes patients. The purpose of the current study was to evaluate gender differences in the association between sUA level and arteriosclerotic cardiovascular risk in Chinese type 2 diabetes patients. METHODS: The cross-sectional study was conducted in six community health service centers in Shanghai, China from December 2014 to December 2016. A stratified random sampling method was used to recruit participants. From a total of 3977 type 2 diabetic patients, 2537 were included for the analysis of the association between sUA level and arteriosclerotic cardiovascular risk. Clinical and biochemical data were obtained from participants. Arteriosclerotic cardiovascular risk was evaluated by the ten-year risk profile for arteriosclerotic cardiovascular disease. The associations between sUA level and arteriosclerotic cardiovascular risk were assessed via multiple logistic regression. RESULTS: Of the 2537 participants, the average sUA level was 317±77umol/L in men and 294±73 umol/L in women, and 54.8% (1391/2537) of participants had high ten-year risk of arteriosclerotic cardiovascular disease (ASCVD), which was ≥20%. High ten-year risk of ASCVD odds ratio was increased by 1.596 (95% CI, 1.113-2.289, p for trend 0.004) comparing fourth to first quartiles of sUA in women. However, no significant association was found between sUA and high ten-year risk of ASCVD in men. CONCLUSION: This community-based study indicated that sUA levels were independently associated with high ten-year risk of ASCVD in women with type 2 diabetes mellitus, but not in men.

7.
J Glaucoma ; 29(11): 1001-1005, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32941321

RESUMEN

PRECIS: Aerosols generated by a noncontact tonometer (NCT) were quantified. There was a positive correlation between aerosols and intraocular pressure (IOP), and the concentration of aerosols beside the air jet port was the highest. PURPOSE: To investigate the effects of IOP on the aerosol density generated during the use of an NCT and provide references and suggestions for daily protection of ophthalmic medical staff during the coronavirus disease-19 (COVID-19) outbreak. OBJECTIVE AND METHODS: This cross-sectional clinical trial included 214 eyes of 140 patients from a hospital in Wenzhou city, Zhejiang Province. All subjects' IOPs were measured by an NCT (39 eyes with low IOP, 90 eyes with normal IOP, 37 eyes with moderately high IOP, and 48 eyes with very high IOP) between March 7 and June 17, 2020. The density of particulate matter (PM) 2.5 and PM10 generated during the process of IOP measurement with an NCT was analyzed. IOP values were recorded simultaneously. The aerosols generated during different IOP measurements were plotted in scatter plots. RESULTS: PM2.5 was generated more at the air jet port of the tonometer during the process of IOP measurement (H=2.731, P=0.019). Larger quantities of PM2.5 and PM10 were generated when the IOP was higher, and these differences were statistically significant (PM2.5: H=119.476, P<0.001; PM10: H=160.801, P<0.001). Linear correlation analysis with one variable demonstrated that IOP had significantly positive correlations with PM2.5 (r=0.756, P<0.001) and PM10 (r=0.864, P<0.001). CONCLUSIONS: Aerosols can be generated while using an NCT to measure IOP, and aerosols and IOP are positively correlated. Patients with moderately high IOP or very high IOP tend to generate more aerosols during the IOP measurement. The concentration of aerosols beside the air jet port was the highest.


Asunto(s)
Aerosoles/química , Betacoronavirus , Infecciones por Coronavirus/transmisión , Transmisión de Enfermedad Infecciosa de Paciente a Profesional/prevención & control , Presión Intraocular/fisiología , Neumonía Viral/transmisión , Lágrimas/química , Tonometría Ocular/instrumentación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , COVID-19 , China/epidemiología , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pandemias , SARS-CoV-2 , Adulto Joven
8.
ACS Appl Mater Interfaces ; 11(4): 4302-4310, 2019 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-30411874

RESUMEN

Excessive radicals and UV irradiation can trigger oxidative and physiological stresses, which cause tissue aging, human disease, food spoilage, and material degradation. In this study, a multifunctional cellulose ester containing hindered phenol groups, cellulose 3,5-di- tert-butyl-4-hydroxybenzoate (CBH), with free-radical-scavenging and UV-resistant activities was synthesized and used as a functional material. The obtained CBHs can effectively scavenge reactive nitrogen free radicals and hydroxyl free radicals in both solid and solution states. Moreover, CBHs have no cytotoxicity, and, on the contrary, they promote the proliferation of human epidermal keratinocytes. Benefiting from excellent solubility, processability, and formability, CBHs have been readily processed into flexible films, transparent coatings, and nanoribbons membranes. The highly transparent and flexible CBH film completely absorbs the light of 200-300 nm range and partially absorbs the light of 300-400 nm range, indicating a UV-shielding capability. After the CBHs were loaded on an ordinary facial mask by electrospinning or added into a hand cream, the resultant facial mask and hand cream exhibited outstanding free-radical-scavenging properties. In addition, CBHs can also be used to fabricate functional sprays with antioxidative and UV-shielding activities. Accordingly, the obtained CBHs have a huge potential in cosmetics, personal care products, biopharmaceuticals, papermaking, and art protection because of their excellent antioxidation, nontoxicity, UV resistance, formability, and odorless properties.


Asunto(s)
Celulosa/química , Radicales Libres/química , Fenoles/química , Rayos Ultravioleta , Antioxidantes/química , Depuradores de Radicales Libres/química , Oxidación-Reducción/efectos de la radiación
9.
Carbohydr Polym ; 219: 56-62, 2019 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-31151546

RESUMEN

Two new groups of cellulose esters with a substituent, either trifluoromethylbenzoate or methylbenzoate, were synthesized in homogeneous conditions. The actual presence of aromatic substituents was demonstrated by 1H-NMR spectra. The mechanical and structural peculiarities were determined by Depth Sensing Indentation (DSI) and Positron Annihilation Lifetime Spectroscopy (PALS) techniques. The relative position of CH3 and CF3 groups on the aromatic substituents influences the molecular packing differently and affects the formation of free volumes. The hardness characteristics and modulus of the corresponding cellulose esters were the lowest when the CH3 and CF3 groups are in m-position on the aromatic substituents. Meanwhile, they exhibited the highest number density of the free volume holes, as revealed by the o-Ps intensity values. An inverse linear relationship between the hardness, respectively on the modulus, and the o-Ps intensity was found. A simplified scheme of the structural feature of the investigated cellulose esters was proposed.

10.
ACS Appl Mater Interfaces ; 10(2): 2114-2121, 2018 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-29260855

RESUMEN

Iron ions play a vital role in many biological processes, and their concentrations are responsible for human health. Therefore, it is essential to detect the concentration of iron ions by a rapid, accurate, highly selective, and practical method. Herein, we have synthesized a cellulose-based fluorescent sensor (Phen-MDI-CA) for the highly selective and rapid detection of Fe2+ ions via chemically bonding 1,10-phenanthroline-5-amine (Phen) onto cellulose acetate (CA) using 4,4'-methylene diphenyl diisocyanate (MDI) as a cross-linker. Benefiting from the anchoring and diluting effect of a cellulose skeleton, the resultant Phen-MDI-CA displays excellent fluorescence properties in both solution and solid state. More interestingly, a cellulose-based polymer chain significantly improves the sensitivity of phenanthroline to Fe2+ ions. Upon meeting Fe2+ ions, a red, insoluble, and nonfluorescent Fe-(Phen-MDI-CA) complex appears immediately; thus, Phen-MDI-CA can work as a multimode chromogenic sensor for the highly selective, sensitive, and rapid detection of Fe2+ ions. In the instrument-free visual mode, the detection limit for Fe2+ ions is 50 ppb, and in fluorescence mode, the detection limit is 2.6 ppb. To our knowledge, this is the first time that such a low detection limit for Fe2+ ions in aqueous media has been observed by the naked eye. In addition, Phen-MDI-CA has good solubility and processability in common organic solvents, which facilitates its use in different material forms, e.g., printing ink, coating, and film. Therefore, the Fe2+-responsive and chromogenic Phen-MDI-CA exhibits a huge potential in the detection and extraction of Fe2+ ions.

11.
J Diabetes Res ; 2017: 3901392, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29464182

RESUMEN

Knowledge-attitude-practices (KAP) significantly impact the outcome of self-management in patients with diabetes, yet the association between KAP and the combined control of the levels of blood glucose, blood pressure, and blood lipids in these patients remains uncertain. This community-based cross-sectional study was conducted from December 2014 to December 2016 on 3977 patients with type 2 diabetes in Shanghai. KAP were evaluated using the modified Chinese version of the Diabetes, Hypertension and Hyperlipidemia (DHL) Knowledge Instrument, Diabetes Empowerment Scale-Short Form (DES-SF), and Summary of Diabetes Self-Care Activities (SDSCA). Clinical and biochemical measurements were performed at each sampling site. The association between KAP scores and achieving the combined target goal was assessed by multiple logistic regression. Patients having a higher score of knowledge were more likely to achieve the combined target goal. Furthermore, a turning point of knowledge score was found that the possibility of achieving the combined target goal presented a sharp increase when the knowledge score was more than 70. However, the scores of attitude and practices had no significant relations with achieving the combined target goal. Health intervention strategies, especially increasing integrated diabetes knowledge, should be targeted to patients with type 2 diabetes in communities.


Asunto(s)
Glucemia , Presión Sanguínea/fisiología , Diabetes Mellitus Tipo 2/sangre , Conocimientos, Actitudes y Práctica en Salud , Lípidos/sangre , Anciano , China , Estudios Transversales , Diabetes Mellitus Tipo 2/fisiopatología , Diabetes Mellitus Tipo 2/psicología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Automanejo , Factores Sexuales
12.
ACS Appl Mater Interfaces ; 9(5): 4998-5005, 2017 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-28094492

RESUMEN

Here, we describe an in situ approach for growing polyepoxides from the surfaces of graphene oxide (GO) using a surface-initiated polymerization reaction. The polymerization methodology is facile and general as a broad range of epoxides carrying various functional groups have been successfully polymerized by simply adding GO powders in the epoxide monomers. The resultant polyepoxide grafted GO are found to show enhanced dispersibility in various common solvents and to exhibit increased d-spacing between the basal planes. In particular, grafting poly(2,3-epoxy-1-propanol) (PEP) to GO results in a composite (i.e., GO-g-PEP) that is dispersible in water and miscible with polyether block amide, i.e., Pebax MH 1657. Preliminary studies have indicated the membranes prepared using Pebax/GO-g-PEP composites exhibit enhanced CO2 permeabilities and selectivities in comparison to H2, O2, or N2. The excellent performance in gas separation is attributed to the layered structure of the GO-g-PEP sheets with enlarged d-spacing and the functional groups present on the PEP chains grafted to the surfaces of GO sheets.

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