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1.
China CDC Wkly ; 6(31): 767-771, 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39118872

RESUMEN

What is already known on this topic?: A new conceptual term, small and vulnerable newborns (SVN), bringing preterm birth, small for gestational age (SGA), or low birth weight (LBW) together is being advocated for assessing whether a child is at high risk. What is added by this report?: According to the new conceptual term, the increasing incidence of high-risk newborns (from 9.82% to 10.96%) has been observed among 2,005,408 newborns over the period from 2013 to 2022, which is higher than using any of the three definitions of SVN. Maternal age ≥35, primiparity, and multiple births are high risks for SVN. What are the implications for public health practice?: The new conceptual framework should be used to better assess the number of high-risk newborns. Attention should be paid to multiple births to prevent preterm-related SVN. To reduce term newborns who are SGA, we need to be concerned not only with multiple pregnancies but also with first-time mothers.

2.
China CDC Wkly ; 6(31): 786-792, 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39118870

RESUMEN

What is already known about this topic?: With socioeconomic development, the increase of older pregnancies and multiparas has brought risks to mothers and infants. What is added by this report?: As parities increased, the proportion of women of advanced maternal age (AMA) and non-local domicile increased, while the proportion of women with higher education levels decreased. Women with ≥3 parities are more likely to have preterm birth (PTB) and macrosomia. What are the implications for public health practice?: A comprehensive analysis of pregnancy traits among women at different parities offers a robust foundation for tailored strategies against adverse pregnancy outcomes.

3.
Acta Biomater ; 178: 287-295, 2024 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-38395101

RESUMEN

Single-molecule-based synergistic phototherapy holds great potential for antimicrobial treatment. Herein, we report an orthogonal molecular cationization strategy to improve the reactive oxygen species (ROS) and hyperthermia generation of heptamethine cyanine (Cy7) for photodynamic and photothermal treatments of bacterial infections. Cationic pyridine (Py) is introduced at the meso­position of the asymmetric Cy7 with intramolecular charge transfer (ICT) to construct an atypical electron-transfer triad, which reduces ΔES1-S0, circumvents rapid charge recombination, and simultaneously enhances intersystem crossing (ISC) based on spin-orbit charge-transfer ISC (SOCT-ISC) mechanism. This unique molecular construction produces anti-Stokes luminescence (ASL) because the rotatable CN bond enriched in high vibrational-rotational energy levels improves hot-band absorption (HBA) efficiency. The obtained triad exhibits higher singlet oxygen quantum yield and photothermal conversion efficiency compared to indocyanine green (ICG) under irradiation above 800 nm. Cationization with Py enables the triad to target bacteria via intense electrostatic attractions, as well as biocidal property against a broad spectrum of bacteria in the dark. Moreover, the triad under irradiation can enhance biofilm eradication performance in vitro and statistically improve healing efficacy of MRSA-infected wound in mice. Thus, this work provides a simple but effective strategy to design small-molecule photosensitizers for synergistic phototherapy of bacterial infections. STATEMENT OF SIGNIFICANCE: We developed an orthogonal molecular cationization strategy to enhance the reactive oxygen species and thermal effects of heptamethine cyanine (Cy7) for photodynamic and photothermal treatments of bacterial infections. Specifically, cationic pyridine (Py) was introduced at the meso­position of the asymmetric Cy7 to construct an atypical electron-transfer triad, which reduced ΔES1-S0, circumvented rapid charge recombination, and simultaneously enhanced intersystem crossing (ISC). This triad, with a rotatable CN bond, produced anti-Stokes luminescence due to hot-band absorption. The triad enhanced antimicrobial performance and statistically improved the healing efficacy of MRSA-infected wounds in mice. This site-specific cationization strategy may provide insights into the design of small molecule-based photosensitizers for synergistic phototherapy of bacterial infections.


Asunto(s)
Infecciones Bacterianas , Fotoquimioterapia , Animales , Ratones , Fármacos Fotosensibilizantes/química , Especies Reactivas de Oxígeno , Fototerapia , Colorantes , Infecciones Bacterianas/tratamiento farmacológico , Piridinas/farmacología
4.
Carbohydr Polym ; 328: 121732, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38220349

RESUMEN

Oxidation of polysaccharides can provide biomaterials with aldehyde and ketone functional groups, which are particularly useful in biomedical applications, like drug delivery, tissue adhesion and hydrogel preparation. However, despite their potential, only a few such methods have been reported, and achieving selective, quantitative oxidation of polysaccharides remains challenging. Herein we report utilization of a mild oxidant, Dess-Martin periodinane, for the chemoselective oxidation of hydroxypropyl cellulose (HPC) and hydroxyethyl cellulose (HEC). Our findings reveal that the oxidation of HPC is fast, efficient and achieves near-quantitative conversion. Moreover, both Ox-HPC and Ox-HEC exhibit low cell toxicity, and readily form hydrogels by reaction with a polypeptide comprising amino acids with amine-containing a-substituents, α-poly-l-lysine. The peptide/polysaccharide hydrogels display self-healing properties, injectability, and antimicrobial activity, making them highly attractive for biomedical applications including in wound dressings.


Asunto(s)
Celulosa , Hidrogeles , Hidrogeles/química , Celulosa/química , Polisacáridos , Sistemas de Liberación de Medicamentos , Derivados de la Hipromelosa , Péptidos
5.
Polymers (Basel) ; 15(10)2023 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-37242903

RESUMEN

A thermal-oxidative aging test at 120 °C was conducted on ethylene propylene diene monomer (EPDM) vulcanizates of the semi-efficient vulcanization system. The effect of thermal-oxidative aging on EPDM vulcanizates was systematically studied by curing kinetics, aging coefficient, crosslinking density, macroscopic physical properties, contact angle, Fourier Transform Infrared Spectrometer (FTIR), Thermogravimetric analysis (TGA) and thermal decomposition kinetics. The results show that the content of hydroxyl and carbonyl groups as well as the carbonyl index increased with increasing aging time, indicating that EPDM vulcanizates were gradually oxidized and degraded. As a result, the EPDM vulcanized rubber chains were crosslinked with limited conformational transformation and weakened flexibility. The thermogravimetric analysis demonstrates that the thermal degradation of EPDM vulcanizates had competitive reactions of crosslinking and degradation, and the thermal decomposition curve can be divided into three stages; meanwhile, the thermal stability of EPDM vulcanizates gradually decreased with increasing aging time. The introduction of antioxidants in the system can promote the crosslinking speed and reduce the crosslinking density of EPDM vulcanizates while inhibiting the surface thermal and oxygen aging reaction. This was attributed to the fact that the antioxidant can reduce the thermal degradation reaction level, but it is not conducive to the formation of a perfect crosslinking network structure and reduces the activation energy of thermal degradation of the main chain.

6.
ACS Omega ; 8(1): 1375-1388, 2023 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-36643466

RESUMEN

To investigate the effect of concentration of N2 and CO2 (0, 10, 20, 30, 40, and 50%) on the flame propagation characteristics of CH4/air premixed gases with stoichiometric ratios in variable cross-section ducts, experiments were conducted in four combinations of ducts at initial conditions of 298 K and 1 atm. The results show that the flame propagation velocity, propagation time, and overpressure are greater in the suddenly contracted duct than in the suddenly expanded duct if the dimensions of the ducts are kept constant. However, an increase in inert gas concentration leads to a decrease in flame propagation speed, an increase in flame propagation time, and changes in flame structure and pressure. "Tulip" flames appeared when a duct with a cross section of 100 mm × 100 mm was combined with a duct with a cross section of 70 mm × 70 mm, whether N2 or CO2 was added or what its concentration was. However, when a duct with a cross section of 140 mm × 140 mm was combined with a 70 mm × 70 mm duct, a "tulip" flame is formed only at a CO2 concentration of 50%. As the concentration of inert gas increases, the explosion pressure first decreases and then stabilizes, while the rate of pressure increase showed a monotonically decreasing trend. The explosion pressure is minimized when the concentration of CO2 and N2 is 30 and 40%, respectively.

7.
Arch Gynecol Obstet ; 301(3): 837-844, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32114674

RESUMEN

OBJECTIVE: The study intends to explore the functions of maternal high-fat diet exposure on progeny weight and heart. METHODS: Sprague-Dawley (SD) rats, fed on a high-fat diet, were used to establish a model of weight gain before and during pregnancy. The body and cardiac weight of neonatal, 1-month- and 3-month-old rats were measured. The morphology of myocardial cells was observed by hemotoxylin and eosin (H&E) staining. The expression of caspase-3, 8, 9 was measured by qRT-PCR and western blot. RESULTS: Normal pregnant rats, fed on a high-fat diet throughout pregnancy, had a significant increase in body and cardiac weight of their neonates, and more fat deposition in myocardial cells and an increased expression of caspase-3, 8, 9, compared with that of the normal pregnant rats + normal diet group. These phenomena were relieved through later diet control. Pregnant rats, which fed on a high-fat diet throughout pregnancy, showed more adverse effects on neonatal body and cardiac weight, myocardial cell fat deposition, and the expression of caspase-3, 8, 9, compared with pregnant rats exposed to high-fat diet + normal diet and pregnant rats exposed to high-fat diet + normal diet + exercise. These phenomena cannot be fully restored via controlling later diet. CONCLUSIONS: Our results stated that a proper diet before and during pregnancy was important for the cardiac health of offspring.


Asunto(s)
Dieta Alta en Grasa/efectos adversos , Exposición Materna/efectos adversos , Fenómenos Fisiologicos Nutricionales Maternos/fisiología , Miocitos Cardíacos/metabolismo , Obesidad Materna/complicaciones , Animales , Apoptosis , Femenino , Humanos , Masculino , Embarazo , Efectos Tardíos de la Exposición Prenatal , Ratas , Ratas Sprague-Dawley
8.
Polymers (Basel) ; 10(8)2018 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-30960797

RESUMEN

Maleic anhydride (MAH)⁻divinyl benzene (DVB) multi-monomer melt-grafting onto isotactic polybutene-1 (iPB-1) was carried out in a torque rheometer. The effects of dicumyl peroxide (DCP), MAH, and DVB concentrations, and temperature, on the reaction, were investigated. The optimized conditions were 170 °C, DVB/MAH = 4:6 (mass ratio). DVB as a comonomer enhanced the grafting degree (Gd) and grafting efficiency (Ge) of iPB-g-MAH better than styrene. The initiator DCP had little effect on Gd as its concentration over 0.2 phr, but the grafts' melt flow rate (MFR) increased significantly, and relative molecular weight decreased remarkably with increased DCP concentration. With increasing Gd, the contact angle of grafts with water decreased, and there was a larger crystallization rate. The study of iPB-1 and iPB-g-MAH (Gd = 1.5%)-modified polyamide 6 (PA6) showed that iPB-g-MAH had an obviously toughening effect on PA6. With increasing iPB-g-MAH concentration, the blends of impact strength and elongation at break increased obviously, tensile strength decreased slightly, and MFR decreased prominently, which greatly slowed the processing degradation of PA6. The properties of iPB-1/PA6 blends deteriorated. Both DSC curves and SEM micrographs confirmed that PA6/iPB-g-MAH blends had much better compatibility than PA6/iPB. The reason was that the anhydride group in iPB-g-MAH reacted with amide group in PA6 to improve the compatibility between two phases, and iPB-g-MAH is an excellent modifier for PA6.

9.
World J Urol ; 35(7): 1133-1139, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27803968

RESUMEN

OBJECTIVE: To determine the sensitivity and specificity of 640-Multislice CT (640-MSCT) in diagnosing the female UD. MATERIALS AND METHODS: We investigated 16 patients with symptomatic UDs preoperatively in our hospital from August 2010 to March 2016. The patients' average age was 38.8 years. All patients were performed 640-MSCT of pelvis; then, 3D and 4D images were reconstructed preoperatively. RESULTS: In 3D and 4D-CT images, out of 16 patients, thirteen patients had one ostium, two had 2 ostia and one had 3 ostia. Out of those thirteen patients, eight patients' ostia were located at 5 o'clock and five patients' at 7 o'clock. Patients with 2 ostia location were at 5 and 6 o'clock and 5 and 7 o'clock, respectively. Patients with 3 ostia location were at 5, 6 and 7 o'clock. The mean distance from the bladder neck to the ostia was 22.5 mm. The shape of UD was out-pouching in 11 patients (68.8%), U-shaped in four patients (25.0%) and circumferential in 1 patient (6.2%). The CT findings were confirmed by surgical findings. CONCLUSIONS: 640-MSCT is a useful tool in identifying UD's shape and ostium (including number, location) before operation. Preoperative 640-MSCT should be an adaptable modality for clinically suspected UD patients. ADVANCES IN KNOWLEDGE: Several imaging methods have been used to diagnose female UD. 640-MSCT may be more suitable to diagnose it for its higher sensitivity and specificity in diagnosis of female UD, especially in identifying UD's shape and number and location of ostium.


Asunto(s)
Divertículo/diagnóstico , Tomografía Computarizada Cuatridimensional/métodos , Tomografía Computarizada Multidetector/métodos , Uretra/diagnóstico por imagen , Enfermedades Uretrales/diagnóstico , Adulto , Divertículo/cirugía , Femenino , Humanos , Persona de Mediana Edad , Planificación de Atención al Paciente , Cuidados Preoperatorios/métodos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Uretra/patología , Uretra/cirugía , Enfermedades Uretrales/cirugía , Procedimientos Quirúrgicos Urológicos/métodos
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