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1.
Nano Lett ; 24(10): 3176-3185, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38436575

RESUMEN

Inspired by the reverse thrust generated by fuel injection, micromachines that are self-propelled by bubble ejection are developed, such as microrods, microtubes, and microspheres. However, controlling bubble ejection sites to build micromachines with programmable actuation and further enabling mechanical transmission remain challenging. Here, bubble-propelled mechanical microsystems are constructed by proposing a multimaterial femtosecond laser processing method, consisting of direct laser writing and selective laser metal reduction. The polymer frame of the microsystems is first printed, followed by the deposition of catalytic platinum into the desired local site of the microsystems by laser reduction. With this method, a variety of designable microrotors with selective bubble ejection sites are realized, which enable excellent mechanical transmission systems composed of single and multiple mechanical components, including a coupler, a crank slider, and a crank rocker system. We believe the presented bubble-propelled mechanical microsystems could be extended to applications in microrobotics, microfluidics, and microsensors.

2.
Nat Commun ; 15(1): 1443, 2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38365791

RESUMEN

Despite their notable unidirectional water transport capabilities, Janus membranes are commonly challenged by the fragility of their chemical coatings and the clogging of open microchannels. Here, an on-demand mode-switching strategy is presented to consider the Janus functionality and mechanical durability separately and implement them by simply stretching and releasing the membrane. The stretching Janus mode facilitates unidirectional liquid flow through the hydrophilic micropores-microgrooves channels (PG channels) fabricated by femtosecond laser. The releasing protection mode is designed for the in-situ closure of the PG channels upon encountering external abrasion and impact. The protection mode imparts the Janus membrane robustness to reserve water unidirectional penetration under harsh conditions, such as 2000 cycles mechanical abrasion, 10 days exposure in air and other rigorous tests (sandpaper abrasion, finger rubbing, sand impact and tape peeling). The underlying mechanism of gridded grooves in protecting and enhancing water flow is unveiled. The Janus membrane serves as a fog collector to demonstrate its unwavering mechanical durability in harsh real-world conditions. The presented design strategy could open up new possibilities of Janus membrane in a multitude of applications ranging from multiphase separation devices to fog harvesting and wearable health-monitoring patches.

3.
Lab Chip ; 24(4): 832-842, 2024 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-38235769

RESUMEN

Magnetically-actuated microrobots (MARs) exhibit great potential in biomedicine owing to their precise navigation, wireless actuation and remote operation in confined space. However, most previously explored MARs unfold the drawback of hypodynamic magnetic torque due to low magnetic content, leading to their limited applications in controlled locomotion in fast-flowing fluid and massive cargo carrying to the target position. Here, we report a high-performance pure-nickel magnetically-actuated microrobot (Ni-MAR), prepared by a femtosecond laser polymerization followed by sintering method. Our Ni-MAR possesses a high magnetic content (∼90 wt%), thus resulting in enhanced magnetic torque under low-strength rotating magnetic fields, which enables the microrobot to exhibit high-speed swimming and superior cargo carrying. The maximum velocity of our Ni-MAR, 12.5 body lengths per second, outperforms the velocity of traditional helical MARs. The high-speed Ni-MAR is capable of maintaining controlled locomotion in fast-flowing fluid. Moreover, the Ni-MAR with massive cargo carrying capability can push a 200-times heavier microcube with translation and rotation motion. A single cell and multiple cells can be transported facilely by a single Ni-MAR to the target position. This work provides a scheme for fabricating high-performance magnetic microrobots, which holds great promise for targeted therapy and drug delivery in vivo.

4.
Front Cardiovasc Med ; 10: 1237103, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38034370

RESUMEN

Background: Only a few studies that investigated dietary intakes of folate, vitamin B6, and vitamin B12 in relation to cariovascular disease (CVD). This study aimed to assess the association of dietary folate, vitamin B6, and vitamin B12 with CVD in the United States population. Methods: A cross-sectional analysis of 65,322 adults aged ≥ 20 years who participated in the Third National Health and Nutrition Examination Survey (NHANES III) and NHANES 1999-2018. Before 2003, dietary intake data were assessed using a 24-hour dietary call, and two 24-hour dietary calls were used during 2003 and 2018. Odds ratios and 95% confidence intervals (CIs) for CVD associated with dietary folate, vitamin B6, and vitamin B12 were estimated using multivariate logistic regression models. Results: Dietary vitamin B6 intake were inversely associated with the odds of CVD. In males, the multivariable OR for the highest vs. lowest quartiles of vitamin B6 was 0.77 (95%CI: 0.61-0.97, Ptrend = 0.013) for the odds of CVD. In females, the adjusted OR for the highest quartile of vitamin B6 compared with the lowest quartile was 0.73 (95%CI: 0.56-0.95, Ptrend = 0.038) for the odds of CVD. No significant association was observed between dietary folate and vitamin B12 intakes and the odds of CVD. Conclusions: Our findings indicate that higher intake of dietary vitamin B6 may be associated with lower prevalence of CVD, suggesting that dietary vitamin B6 has major public health implications in the prevention of CVD in the United States population.

5.
Sci Rep ; 13(1): 14999, 2023 09 11.
Artículo en Inglés | MEDLINE | ID: mdl-37696922

RESUMEN

This study differentiates myocardial infarction (MI) and strangulation death (STR) from the perspective of amino acid metabolism. In this study, MI mice model via subcutaneous injection of isoproterenol and STR mice model by neck strangulation were constructed, and were randomly divided into control (CON), STR, mild MI (MMI), and severe MI (SMI) groups. The metabolomics profiles were obtained by liquid chromatography-mass spectrometry (LC-MS)-based untargeted metabolomics. Principal component analysis, partial least squares-discriminant analysis, volcano plots, and heatmap were used for discrepancy metabolomics analysis. Pathway enrichment analysis was performed and the expression of proteins related to metabolomics was detected using immunohistochemical and western blot methods. Differential metabolites and metabolite pathways were screened. In addition, we found the expression of PPM1K was significantly reduced in the MI group, but the expression of p-mTOR and p-S6K1 were significantly increased (all P < 0.05), especially in the SMI group (P < 0.01). The expression of Cyt-C was significantly increased in each group compared with the CON group, especially in the STR group (all P < 0.01), and the expression of AMPKα1 was significantly increased in the STR group (all P < 0.01). Our study for the first time revealed significant differences in amino acid metabolism between STR and MI.


Asunto(s)
Metabolómica , Infarto del Miocardio , Animales , Ratones , Secuencias de Aminoácidos , Western Blotting , Infarto del Miocardio/diagnóstico , Aminoácidos
6.
Int J Biol Macromol ; 243: 125119, 2023 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-37263332

RESUMEN

Phosphoric acid has been utilized as a favorable alternative to strong acids for the production of cellulose nanospheres (CNS) in recent years, partly owing to the reduced reliance on mechanical assistance. In the present study, phosphoric acid hydrolysis was applied to synthesize CNS from natural cotton pulp. Compared to reported long-time hydrolysis over 12 h, reduced time of 4 h is achieved for CNS production. Particle size from 530 nm to 1.3 µm was further controlled by changing the hydrolysis time in 4-11 h. Powdered sample was obtained after freeze-drying. CNS prepared in this work exhibits a cellulose II structure. Crystallinity index of the samples locates in 70-75 % which is higher than the reported 43-60 % for the acid-hydrolyzed medical cotton. Moreover, compared to the sulphuric-acid hydrolyzed CNS with higher crystallinity, thermal stability of the CNS generated from phosphoric-acid hydrolysis is significantly greater. A cooperative dissolution-regeneration and degradation is proposed to induce CNS self-assembly. Initial cellulose microfibrils are completely dissolved as exposed to phosphoric acid. Partial chains aggregate as a result while the remaining chains assemble onto the aggregates in a layer-by-layer manner. Acid degradation to cellulose with time affects length of the molecular chains. CNS size is controlled accordingly.


Asunto(s)
Nanopartículas , Nanosferas , Celulosa/química , Solubilidad , Ácidos Fosfóricos/química , Hidrólisis , Nanopartículas/química
7.
Int J Biol Macromol ; 242(Pt 1): 124738, 2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37169056

RESUMEN

Rod-shaped cellulose nanocrystals (CNCs), also called cellulose nanorods (CNRs), possess anisotropic properties that allow for their self-organization into chiral nematic liquid crystals. Interestingly, spherical cellulose nanocrystals (cellulose nanospheres, CNSs) have also been shown to form a chiral liquid-crystalline phase in recent years. Herein, to understand how the similar assembly takes places as particle dimension changes, the organization features of CNSs were investigated. Results of this study demonstrate that above a critical concentration in suspension, CNSs organize into a liquid-crystal phase consisting of periodically parallel-aligned layer structures. This structure persists after suspension drying. In comparison with CNRs, the alignment of CNSs exhibits a shorter layer distance, lower order degree, and weaker long-range orientation. To explain the early stages of tactoid formation, a "caterpillar-like" model was proposed, which was captured by freezing the CNS suspension in an intermediate aggregation state. This structure serves as the fundamental unit for further liquid-crystal assembly.


Asunto(s)
Cristales Líquidos , Nanosferas , Nanotubos , Celulosa/química , Cristales Líquidos/química , Anisotropía , Suspensiones
8.
Opt Lett ; 48(10): 2508-2511, 2023 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-37186706

RESUMEN

Structural color (SC) has enormous potential for improving the visualization and identification of functional micro/nano structures for information encryption and intelligent sensing. Nevertheless, achieving the direct writing of SCs at the micro/nano scale and the change of color in response to external stimuli simultaneously is rather challenging. To this end, we directly printed woodpile structures (WSs) utilizing femtosecond laser two-photon polymerization (fs-TPP), which demonstrated obvious SCs under an optical microscope. After that, we achieved the change of SCs by transferring WSs between different mediums. Furthermore, the influence of laser power, structural parameters, and mediums on the SCs was systematically investigated, and the mechanism of SCs using the finite-difference time-domain (FDTD) method was further explored. Finally, we realized the reversible encryption and decryption of certain information. This finding holds broad application prospects in smart sensing, anti-counterfeiting tags, and advanced photonic devices.

9.
Nutr Res ; 112: 46-54, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36965328

RESUMEN

We hypothesized that the prevalence of hypertension is related to B-vitamin intake in the general population, but it has not been sufficiently studied. This study aimed to investigate the intakes of dietary folate, vitamin B6, and vitamin B12 concerning hypertension in US adults. A total of 55 569 adults from National Health and Nutrition Examination Survey III and 1999-2014 were included in this study. Nutrient intake was collected from subjects through one or two 24-hour dietary reviews. Multiple logistic regression models were used to examine the relationship between these nutrient intakes and hypertension. Among male participants, dietary folate, vitamin B6, and vitamin B12 intakes were significantly and negatively associated with the prevalence of hypertension, with multivariate-adjusted odds ratios (ORs) of 0.61 (95% confidence interval [CI], 0.55-0.68), 0.65 (95% CI, 0.59-0.72), and 0.84 (95% CI, 0.75-0.95) for the highest quartile group compared with the lowest group. Results were similar for female participants, with multivariate-adjusted ORs of 0.63 (95% CI, 0.57-0.71), 0.60 (95% CI, 0.53-0.66), and 0.87 (95% CI, 0.77-0.98) for the highest quartile group. Moreover, there was a linear trend (Ptrend < .001) in both men and women that the prevalence of hypertension tended to decrease with increased intake of folate, vitamin B6, and vitamin B12; however, the decreases above the third quartile were negligible. Dietary folate, vitamin B6, and vitamin B12 were significantly associated negatively with hypertension, indicating that these nutrients might have a protective effect against hypertension in United States adults.


Asunto(s)
Ácido Fólico , Hipertensión , Complejo Vitamínico B , Adulto , Femenino , Humanos , Masculino , Ácido Fólico/administración & dosificación , Encuestas Nutricionales , Prevalencia , Piridoxina , Vitamina B 12/administración & dosificación , Vitamina B 6/administración & dosificación , Hipertensión/epidemiología , Adolescente , Persona de Mediana Edad
10.
Nat Prod Res ; 37(24): 4099-4111, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36710469

RESUMEN

The targeted identification of α-glucosidase inhibitors from the crude ethyl acetate of Lycopodiella cernua (L.) Pic. Serm (L.cernua) was guided by high-resolution inhibition profiling. The α-glucosidase inhibition profiling and HPLC-QTOF-MS showed tannins and serratenes were the corresponding antidiabetic constituents. Two new serratenes named 3ß, 21ß-dihydroxyserra-14-en-24-oic acid-3ß-(4'-methoxy-5'-hydroxybenzoate) (4), 3ß, 21α-dihydroxyserra-14-en-24-oic acid-3ß-(4'-methoxy-5'-hydroxybenzoate) (7), together with two known compounds (5 and 6) were isolated. Their structures were elucidated by HR-ESI-MS and NMR. Compounds 5-7 inhibited the α-glucosidase activity in a non-competitive manner with Ki values ranging from 1.29 to 12.9 µM. The molecular docking result unveiled that 4-7 bound to the residues at the channel site, which enabled to block the substrate access. In addition, the molecular dynamics (MD) simulation of the most active compound 7 and α-glucosidase indicated the 4'-methoxy-5'-hydroxybenzoate group formed the stable hydrogen bonds and pi-pi T-shaped interactions with Arg312, Gln350 and Phe300 residues, while the rings D and E were stabilized by hydrophobic interaction.


Asunto(s)
Hipoglucemiantes , alfa-Glucosidasas , Hipoglucemiantes/farmacología , Hipoglucemiantes/química , alfa-Glucosidasas/metabolismo , Simulación del Acoplamiento Molecular , Moduladores Selectivos de los Receptores de Estrógeno , Extractos Vegetales/farmacología , Extractos Vegetales/química , Inhibidores de Glicósido Hidrolasas/farmacología , Hidroxibenzoatos
11.
Tissue Cell ; 80: 101984, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36434828

RESUMEN

Determining myocardial infarction (MI) and mechanical asphyxia (MA) was one of the most challenging tasks in forensic practice. The present study aimed to investigate the potential of fatty acid (FAs) metabolism, and lipid alterations in determining MI and MA. MA and MI mouse models were constructed, and metabolic profiles were obtained by LC-MS-based untargeted metabolomics. The metabolic alterations were explored using the PCA, OPLS-DA, the Wilcoxon test, and fold change analysis. The contents of lipid droplets (LDs) were detected by the transmission scanning electron microscope and Oil red O staining. The immunohistochemical assay was performed to detect CD36 and dysferlin. The ceramide was assessed by LC-MS. PCA showed considerable differences in the metabolite profiles, and the well-fitting OPLS-DA model was developed to screen differential metabolites. Thereinto, 9 metabolites in the MA were reduced, while metabolites were up- and down-regulated in MI. The increased CD36 suggested that MI and MA could enhance the intake of FAs and disturb energy metabolism. The increased LDs, decreased dysferlin, and increased ceramide (C18:0, C22:0, and C24:0) were observed in MI groups, confirming the lipid deposition. The present study indicated significant differences in myocardial FAs metabolism and lipid alterations between MI and MA, suggesting that FAs metabolism and related proteins, certain ceramide may harbor the potential as biomarkers for discrimination of MI and MA.


Asunto(s)
Asfixia , Ceramidas , Ácidos Grasos , Infarto del Miocardio , Animales , Ratones , Asfixia/complicaciones , Biomarcadores/metabolismo , Ceramidas/metabolismo , Disferlina , Ácidos Grasos/metabolismo , Infarto del Miocardio/diagnóstico , Proyectos Piloto
12.
J Ethnopharmacol ; 303: 115951, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36410577

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Tyrosinase, the key rate-limiting enzyme for melanogenesis, is one of the main targets for skin senescence and some pigmented skin diseases, such as albinism and melanoma. Tyrosinase inhibitors are capable of reducing melanin generation and deposition in the skin through blocking the reaction chain of formation. Thus, it has been used for anti-melanoma and showed the potential to be developed into novel skin whitening and spot removing products. With the trend of back-to-nature, natural tyrosinase inhibitors are receiving more and more attention. Traditional Chinese medicines (TCMs) as the promising source of novel chemotypes and pharmacophores, are huge treasures for the discovery of natural tyrosinase inhibitors characterized with green, safe, and highly efficient. AIM OF THIS REVIEW: This review aims to provide a systematic overview of natural tyrosinase inhibitors and a detailed summary of the types of TCMs from which they originate. In addition, this paper also highlights the screening methods developed for exploring tyrosinase inhibitors in recent years, compares the advantages and disadvantages of various methods under the guidance of different screening principles, and predicts their applications in the future. MATERIALS AND METHODS: Relevant literature have been obtained using the keywords "tyrosinase inhibitors", "traditional Chinese medicines", "whitening", and "screening" in scientific databases, such as "PubMed", "SciFinder", "Web of Science", "Elsevier", "China Knowledge Resource Integrated databases". Information was also collected from Chinese pharmacopoeia, Chinese herbal classics books, "Google Scholar", "Baidu Scholar", and other literature sources, etc. RESULTS: An overview about the tyrosinase inhibitors derived from TCMs since 2002 has been compiled via the above-mentioned sources. Up to now, 186 components, mainly belonging to flavonoids, lignans, terpenoids, Diels-Alder adducts, simple phenylpropanoids and stilbenes, from 61 kinds of TCMs have been reported to possess tyrosinase inhibitory activity, among which flavonoids are mainly focused on. Furthermore, on the basis of bioactive detection strategies, the screening methods for tyrosinase inhibitors have been classified into bioaffinity-based, intrinsic enzymatic-based, and computer-aided drug design (CADD). Precisely because screening approaches are essential for rapid identification of tyrosinase inhibitors from TCMs, the principles, advantages and disadvantages, and specific applications of each method are presented along with a comparison of applicability. CONCLUSIONS: The summary of TCMs-derived inhibitors gives a clue on the discovery of candidates with the property to whiten the skin. Meanwhile, the outlook of developed screening methods provides technical references for the efficient exploration of safer and more effective tyrosinase inhibitors from TCMs.


Asunto(s)
Medicamentos Herbarios Chinos , Monofenol Monooxigenasa , Humanos , Medicamentos Herbarios Chinos/farmacología , Flavonoides , Medicina Tradicional China
13.
Small ; 19(2): e2204630, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36382576

RESUMEN

Biomimetic stimuli-responsive structure colors (SCs) can improve the visualization and identification in the micro functional structure field such as information encryption/decryption and smart actuators. However, it is still challenging to develop the ability to 4D print arbitrary submerged colorful patterns with stimuli-responsive materials at the microscale. Herein, a hydrogel photoresist with feature resolution (98 nm) for the fabrication of 4D microscopic SCs by the femtosecond direct laser writing method is developed. The 4D printed woodpile SCs are grouped as pixel palettes with various laser parameters and they spanned almost the entire color space. The coloring mechanism of diffraction gratings is not only investigated by optics microscopy and spectroscopy but also supported by simulation. Moreover, the 4D printed hydrogel-integrated amphichromatic fish constructions and pixelated painting can visually discolor reversibly by regulating the solution pH. This finding promises an ideal coloring method for sensors, anti-counterfeiting labels, and transformable photonic devices.


Asunto(s)
Luz , Fotones , Animales , Hidrogeles/química , Óptica y Fotónica , Rayos Láser
14.
Artículo en Inglés | MEDLINE | ID: mdl-36429919

RESUMEN

Rapid urbanization has reshaped land cover and the ecological environment, potentially improving or deteriorating soil organic carbon (SOC). However, the response of SOC to urbanization has not yet been fully exploited. Herein, by using the land-use transfer matrix, the Sen & Mann-Kendall tests, the Hurst index, and a geographical and temporal weighted regression (GTWR) model, as well as an urban-rural gradient perspective, we assessed the dynamic response of SOC to Beijing's urbanization from 2001 to2015 and identified the main drivers. The results found that SOC stock decreased by 7651.50 t C during the study period. SOC density varied significantly along an urban-rural gradient, with high value areas mainly being located in remote mountainous rural areas and low value areas mainly being located in urban areas on the plains. There was an uneven variation in SOC density across the urban-rural gradient, with suburban areas (25-40 km away from urban cores) losing the most SOC density while urban areas and rural areas remained relatively unchanged. GTWR model revealed the spatio-temporal non-flat stability of various driving forces. Precipitation, the proportion of forest, the proportion of grassland, the population, distance to the urban center, the slope, and the silt content are the main factors related to SOC stock change. As a result, we suggest policy makers reconceptualize the uneven variation in the SOC between urban and rural areas, emphasize suburban areas as a target for controlling SOC loss, and take into consideration the spatial and temporal heterogeneity of the factors influencing SOC stock when evaluating policies.


Asunto(s)
Carbono , Suelo , Carbono/análisis , Beijing , Bosques , Urbanización
15.
Small ; 18(37): e2202272, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35983631

RESUMEN

Micromachines with high environmental adaptability have the potential to deliver targeted drugs in complex biological networks, such as digestive, neural, and vascular networks. However, the low processing efficiency and single processing material of current 4D printing methods often limit the development and application of shape-morphing micromachines (SMMs). Here, two 4D printing strategies are proposed to fabricate SMMs with pH-responsive hydrogels for complex micro-networks traversing. On the one hand, the 3D vortex light single exposure technique can rapidly fabricate a tubular SMM with controllable size and geometry within 0.1 s. On the other hand, the asymmetric multimaterial direct laser writing (DLW) method is used to fabricate SMMs with designable 3D structures composed of hydrogel and platinum nanoparticles (Pt NPs). Based on the presence of ferroferric oxide (Fe3 O4 ) and Pt NPs in the SMMs, efficient magnetic, bubble, and hybrid propulsion modes are achieved. Finally, it is demonstrated that the spatial shape conversion capabilities of these SMMs can be used for narrow micronetworks traversing, which will find potential applications in targeted cargo delivery in microcapillaries.


Asunto(s)
Nanopartículas del Metal , Sistemas de Liberación de Medicamentos , Hidrogeles/química , Platino (Metal) , Impresión Tridimensional
16.
ACS Appl Mater Interfaces ; 14(31): 35366-35375, 2022 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-35914110

RESUMEN

Gating systems have been extensively researched in energy harvesting, lab-on-chip applications, and so forth. However, the controlled drug delivery system with artificial hydrogel-based porous gating systems (HPGSs) is rarely reported. Herein, a biomimetic HPGS with a pH-responsive hydrogel as the valve and polydimethylsiloxane as the frame is fabricated by in situ femtosecond laser microdrilling and subsequent ultraviolet exposure. The proposed HPGS loaded with doxorubicin hydrochloride (DOX) is stable under physiological conditions, has a low drug leakage rate, and can achieve sustained drug release in a low pH environment. The experimental results show that the drug release is mainly controlled by non-Fickian diffusion, which renders the dynamic speed control of molecular transport possible. Moreover, the HPGS can also be prepared into an antitumor microcapsule. The results of in vitro cell experiments demonstrate that DOX@HPGS can release drugs and achieve terrific therapeutic efficacy in the elimination of HeLa cells in the acidic environments around tumor cells. This functional HPGS is envisioned to be an ideal pH-response carrier for sustained drug release treatment of digestive diseases such as inflammatory bowel disease and gastrointestinal cancer.


Asunto(s)
Doxorrubicina , Hidrogeles , Doxorrubicina/química , Doxorrubicina/farmacología , Portadores de Fármacos , Sistemas de Liberación de Medicamentos , Liberación de Fármacos , Células HeLa , Humanos , Hidrogeles/química , Hidrogeles/farmacología , Concentración de Iones de Hidrógeno , Porosidad
17.
Med Res Rev ; 42(5): 1888-1929, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35670013

RESUMEN

Medicinal plants are considered to be a critical source of novel compounds and pharmacophores. The genus Ardisia, consisting of approximately 500 species, is the largest genus in the Myrsinaceae family. Ardisia species are widely distributed throughout tropical and subtropical regions of the world and have been used for the treatment of cancer, hypertension, irregular menstruation, gonorrhea, diarrhea and postnatal syndromes, among others. Phytochemical studies of Ardisia species have resulted in the isolation and identification of 111 compounds, including triterpenoid saponins, quinones, phenols, coumarins, cyclic depsipepetide and flavonoids. Crude extracts and isolates from Ardisia have been reported to have in vitro and in vivo efficacies, including but not limited to anticancer, antiinflammatory, antimicrobial, antioxidant, antithrombotic and antidiabetic, antitubercular compounds. This review focuses on the medical and functional uses, phytochemical profile and pharmacological efficacies of Ardisia species over the past 15 years. This review will provide information indicating that Ardisia species represent an invaluable source of potential therapeutic compounds.


Asunto(s)
Ardisia , Plantas Medicinales , Ardisia/química , Humanos , Medicina Tradicional , Fitoquímicos/farmacología , Extractos Vegetales/química , Extractos Vegetales/farmacología
18.
Environ Sci Pollut Res Int ; 29(54): 82584-82599, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35752673

RESUMEN

This work studies the degradation of chlortetracycline hydrochloride (CTC) by activated peroxymonosulfate (PMS) with natural manganese sand (NMS). Meanwhile, the NMS was characterized and analyzed by isothermal nitrogen adsorption (BET), energy-dispersive X-ray spectroscopy (EDS) and scanning electron microscope (SEM). It can be induced that NMS material may contain C, O, Al, Si, Fe, Mn, and K, and the proportion of each is 6%, 9%, 13%, 34%, 27%, 5%, and 6%. Critical parameters, including initial pH value, catalyst dosage, and PMS amount, were optimized through response surface methodology. One of the essential significances of response surface methodology (RSM) is the establishment and optimization of the mathematical model to reduce the complexity of the experimental process. It can provide the degree of mutual influence between various factors and optimize the response based on the investigated factors. Results indicated that 81.65% of CTC could be degraded under the optimized conditions of PMS amount 2.02 g/L, the NMS dosage 0.29 g/L and pH 3.87. Also, it shows that NMS is the most powerful of each factor on the degradation efficiency. We proposed the degradation pathways of CTC from the liquid chromatograph-mass spectrometer (LC-MS) results. Therefore, NMS could be applied as an efficient activator of peroxymonosulfate to purify the water and wastewater.


Asunto(s)
Clortetraciclina , Peróxidos , Arena , Purificación del Agua , Clortetraciclina/química , Manganeso , Peróxidos/química , Arena/química , Aguas Residuales/química , Agua/química , Purificación del Agua/métodos
19.
Nano Lett ; 22(13): 5277-5286, 2022 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-35728002

RESUMEN

Functional microdevices based on responsive hydrogel show great promise in targeted delivery and biomedical analysis. Among state-of-the-art techniques for manufacturing hydrogel-based microarchitectures, femtosecond laser two-photon polymerization distinguishes itself by high designability and precision, but the point-by-point writing scheme requires mechanical apparatuses to support focus scanning. In this work, by predesigning holograms combined with lens phase modulation, multiple femtosecond laser spots are holographically generated and shifted for prototyping of three-dimensional shape-morphing structures without any moving equipment in the construction process. The microcage array is rapidly fabricated for high-performance target capturing enabled by switching environmental pH. Moreover, the built scaffolds can serve as arrayed analytical platforms for observing cell behaviors in normal or changeable living spaces or revealing the anticancer effects of loaded drugs. The proposed approach opens a new path for facile and flexible manufacturing of hydrogel-based functional microstructures with great versatility in micro-object manipulation.


Asunto(s)
Hidrogeles , Rayos Láser , Hidrogeles/química , Fotones , Polimerizacion
20.
Environ Monit Assess ; 194(5): 390, 2022 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-35449426

RESUMEN

With the rapid development of China's social economy, the phenomenon of unbalanced regional economic development is increasingly obvious. The shortage of water resources in northwest China is an important constraint to local development. The study on the water resources carrying capacity of the Zhuanglang River Basin plays an important role in the development of local economy; thus, we evaluate the water resources situation of Zhuanglang River Basin by using hydrology-related calculation method, combining with field investigation, visiting relevant departments, and referring to relevant data. Meanwhile, the water resources carrying capacity of 3 counties and 12 townships in the Zhuanglang River Basin in the current year are studied and analyzed based on methods such as fuzzy comprehensive evaluation model and quantitative calculation. Results indicate that the carrying capacity of water resources in Zhuanglang river basin can mostly meet the needs of township, but it is necessary to further optimize the water resources carrying capacity of the Zhuanglang River Basin from the four systems of water resources, society, economy, and ecology in the future. Besides, the results of quantitative calculation show that the maximum economic scale that water resources can withstand in most areas of the Zhuanglang River Basin is the overall well-off level, that is, the per capita domestic water is 80L/(d· person), and the per capita GDP is 10000 yuan/person. But there is still a certain gap to achieve the level, when the people are well-off in an all-round way, the two indexes are correspondently raised to 120L/(d· person), and the per capita GDP is 30,000 yuan/person.


Asunto(s)
Ríos , Recursos Hídricos , China , Conservación de los Recursos Naturales , Monitoreo del Ambiente , Humanos , Hidrología
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