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1.
Small ; 20(32): e2312003, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38644338

RESUMEN

Enhancing the thermoelectric performance of n-type polycrystalline SnSe is essential, addressing challenges posed by elevated thermal conductivity and compromised power factor inherent in its intrinsic p-type characteristics. This investigation utilized solid-state reactions and spark plasma sintering techniques for the synthesis of n-type SnSe. A significant improvement in the figure of merit (ZT) is achieved through strategic reduction in Se concentration and optimization of crystal orientation. The co-doping with Br and Ge further improves the material; Br amplifies carrier concentration, enhancing electrical conductivity, while Ge introduces effective phonon scattering centers. In the Br/Ge co-doped SnSe sample, thermal conductivity dropped to 0.38 Wm⁻¹K⁻¹, yielding a remarkable power factor of 662 µW mK- 2 at 773 K, culminating in a ZT of 1.34. This signifies a noteworthy 605% improvement over the pristine sample, underscoring the pivotal role of Ge doping in enhancing n-type material thermoelectric properties. The enhancement is attributed to Br doping introducing additional electronic states near the valence band, and Ge doping modifying the band structure, fostering resonant states near the conduction band. The Br/Ge co-doping further transforms the band structure, influencing electrical conductivity, Seebeck coefficient, and thermal conductivity, advancing the understanding and application of n-type SnSe materials for superior thermoelectric performance.

2.
Purinergic Signal ; 2024 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-38676825

RESUMEN

P2X7 receptor (P2X7R) plays an important role in modulating inflammation and fibrosis, but information is limited whether Zusanli (ST36) can inhibit inflammation and fibrosis by regulating P2X7R. Isoprenaline at 5 mg/kg was subcutaneously injected to wild-type and P2X7R knockout mice for 7 days, while treatment groups received electroacupuncture (EA) stimulation at ST36 for 7 sessions. Following 7-session treatment, Masson's trichrome staining was performed to assess the fibrosis. Morphology, electrocardiogram, and echocardiography were carried out to evaluate the cardiac function and structure. Western blotting, hematoxylin and eosin staining, immunohistochemistry, and biochemical analysis of inflammatory cytokine and transmission electron microscopy were carried out to characterize the effect of ST36 on inflammation. P2X7R was overexpressed in ISO-treated mice. EA at ST36, but not at non-points, reduced ISO-induced cardiac fibrosis, increases in HW/BW, R+S wave relative to mice in ISO groups. In addition, EA at ST36 downregulated ISO-upregulated P2X7R and NLRP3 in ventricle. Moreover, EA reduced cytokines of IL-1ß, IL-6, and IL-18 in serum, and inhibited foam cell gathering, inflammatory cell infiltration, and autophagy. However, EA at ST36 failed to attenuate the cardiac fibrosis and hypertrophy in P2X7R knockout mice. In conclusion, EA at ST36 attenuated ISO-induced fibrosis possibly via P2X7R.

3.
Scand J Clin Lab Invest ; : 1-8, 2024 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-39033335

RESUMEN

The mechanisms underlying subclinical hypothyroidism (SCH) remain unclear, making timely and accurate differentiation between hypothyroidism and SCH, as well as severity assessment, challenging. This study aimed to investigate the role of NFE2 like bZIP transcription factor 2 (Nrf2), gp91phox, and interleukin-17 (IL-17) in the pathogenesis of SCH. In this prospective comparative study, 105 SCH patients, 105 hypothyroidism patients, and 105 healthy individuals were enrolled from January 2022 to August 2023. SCH patients were categorized into mild-moderate and severe groups based on thyroid-stimulating hormone (TSH) levels. Levels of TSH, free T4 (FT4), free T3 (FT3), thyroglobulin antibodies (TG-Ab), thyroid peroxidase antibodies (TPO-Ab), cholesterol (TC), triglycerides (TG), high-density lipoprotein-cholesterol (HDL-ch), and low-density lipoprotein-cholesterol (LDL-ch) were measured. Nrf2, IL-1ß, IL-6, IL-17, and gp91phox levels were tested using ELISA. Nrf2, IL-17 and gp91phox were significantly higher in SCH and hypothyroidism patients compared to the healthy controls, with hypothyroidism patients showing the highest levels. Nrf2 levels were negatively correlated with TSH, TG-Ab and IL-17, but not gp91phox. Nrf2, IL-17 and gp91phox could be used for diagnosis of SCH and severe SCH. Only TG-Ab, IL-17 and gp91phox were independent risk factors for severe SCH. This study demonstrates a negative correlation between serum Nrf2 levels and SCH severity. TG-Ab, IL-17, and gp91phox are independent risk factors, and their associations with SCH pathology suggest their potential roles in the disease mechanism. These findings provide insights into SCH pathogenesis and highlight the need for further research to elucidate their diagnostic or prognostic significance.

4.
Chemistry ; 29(54): e202301569, 2023 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-37394679

RESUMEN

A new pathway via a cyclic intermediate for the synthesis of ketones from aldehydes and sulfonylhydrazone derivatives under basic conditions is proposed. Several control experiments were performed along with analysis of the mass spectra and in-situ IR spectra of the reaction mixture. Inspired by the new mechanism, an efficient and scalable method for homologation of aldehydes to ketones was developed. A wide variety of target ketones were obtained in yields of 42-95 % by simply heating the 3-(trifluoromethyl)benzene sulfonylhydrazones (3-(Tfsyl)hydrazone) for 2 h at 110 °C with aldehydes and with K2 CO3 and DMSO as base and solvent, respectively.

5.
Int J Colorectal Dis ; 38(1): 196, 2023 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-37452920

RESUMEN

OBJECTIVE: Secondary constipation refers to constipation that occurs after certain diseases or medications, such as acute stroke or opioids, and the efficacy of electroacupuncture for secondary constipation is controversial. So, this study aimed to explore the efficacy and safety of electroacupuncture for secondary constipation through a meta-analysis and systematic review. METHOD: We retrieved articles from PubMed, Embase, Cochrane Library, Web of Science, CNKI, Wanfang, and VIP databases up to 28 February 2023. The study was screened strictly according to inclusion and exclusion criteria. Revman5.4 was used for quality evaluation; grade rating was used for index evaluation, and stata15.0 was used for data consolidation analysis. RESULT: Thirteen randomized controlled studies, involving a total of 1437 people (722 electroacupuncture and 715 control groups), were included in this review. Meta-analysis results indicated that electroacupuncture significantly improved constipation overall response (RR = 1.31, 95%CI: 1.11, 1.55, P < 0.001), reduced defecation straining score (MD = - 0.46, 95%CI: - 0.67, - 0.251, P < 0.001), increased weekly complete spontaneous bowel movements (MD = 0.41, 95%CI: 0.20, 0.63, P = 0.002), and increased in the weekly spontaneous bowel movements (MD = 0.80, 95%CI (0.49, 01.11), P < 0.001), and electroacupuncture had no effect on change stool consistency score compared (MD = - 0.03, 95%CI (- 0.38, 0.33), P = 0.88) and did not increase adverse events (RR = 0.50, 95%CI: 0.18, 1.44, P = 0.20). CONCLUSION: According to the current studies, the overall relief rate of patients with secondary constipation after electroacupuncture treatment was improved, the defecation pressure score was reduced, the weekly natural defecation was more complete, and adverse reactions were not increased. Electroacupuncture therefore shows potential for treating constipation, but more high-quality studies are needed to confirm these findings.


Asunto(s)
Electroacupuntura , Humanos , Electroacupuntura/efectos adversos , Defecación , Estreñimiento/terapia , Proyectos de Investigación , Grupos Control
6.
Biotechnol Appl Biochem ; 70(1): 210-220, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35398919

RESUMEN

Recently, composting cultivation method is widely used in oyster mushroom production. In this study, we focused on the effects of composting processes on nutritional qualities and antioxidant activity of Pleurotus floridanus mushroom fruiting bodies. Three treatments of different composting time (2, 4, and 5 days) were performed with an atmospheric sterilization treatment as the control. The results showed that the pH value, total carbon content, and total nitrogen content of substrate were critical parameters which would significantly affect mushroom qualities and bioactivities. Fruiting bodies of the control demonstrated significantly higher crude protein content, total amino acid content, and essential amino acid content than that of composting treatments. Moreover, fruiting bodies of treatment D4 and D5 manifested significantly higher crude polysaccharide contents. Crude polysaccharide of treatment D4 represented the highest scavenging ability toward both radical 3-ethylbenzthiazoline-6-sulfonic acid (ABTS·+ ) and Hydroxyl radical (OH·). It suggests that composting processes is suitable for oyster mushroom cultivation based on nutritional and antioxidant qualities of fruiting bodies.


Asunto(s)
Compostaje , Pleurotus , Prunus persica , Antioxidantes/química , Pleurotus/metabolismo
7.
J Asian Nat Prod Res ; 25(8): 756-764, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36369722

RESUMEN

An efficient and scalable process for the synthesis of 19-hydroxyprogesterone was obtained through seven steps with 34.5% total yield, which is much higher than the process reported in the literature (11.0% total yield). The plausible ring-opening mechanism of 6,19-epoxy bridge in compound 7 was first proposed and the structures of intermediates were supported by the LC-MS analysis of the reaction mixture.

8.
Zhongguo Zhong Yao Za Zhi ; 48(19): 5259-5270, 2023 Oct.
Artículo en Zh | MEDLINE | ID: mdl-38114115

RESUMEN

Moringa oleifera leaves are known for their "Virechana"(purgative) effect in Ayurvedic medicine in India. This study compared the purgative effects and mechanisms of M. oleifera leaves with the reference Rhei Radix et Rhizoma to establish a foundation for the further application of M. oleifera leaves in traditional Chinese medicine(TCM). Using network pharmacology and molecular docking methods, this study identified the material basis, common targets, and signaling pathways through which Rhei Radix et Rhizoma and M. oleifera leaves exerted their purgative pharmacological effects. A low-fiber diet-induced constipation mouse model was established to measure fecal parameters and small intestinal propulsion rate, and histological changes in the colon were observed using HE staining. Relative expression levels of relevant genes and target proteins were assessed using RT-qPCR and immunohistochemistry, respectively. The results showed that mapping the targets of Rhei Radix et Rhizoma and M. oleifera leaves onto the biological process network of constipation revealed close proximity, indicating that they may exert their therapeutic effects on constipation through similar biological processes. Molecular docking results indicated that compounds such as sennoside C and isoquercitrin could target serine/threonine protein kinases(AKT1) and mitogen-activated protein kinase 3(MAPK3), thereby affecting MAPK and calcium signaling pathways to promote defecation. Animal experiments demonstrated that both M. oleifera leaves and Rhei Radix et Rhizoma increased the number of fecal pellets and water content in constipated mice, improved small intestine motility, colon mucosal thickness, and muscle layer thickness, upregulated the gene expression levels of AKT1 and MAPK3 in the colon, and downregulated the expression of AQP3 protein. These findings suggest that M. oleifera leaves and Rhei Radix et Rhizoma share similarities in their therapeutic efficacy and mechanisms for treating constipation. Using Rhei Radix et Rhizoma as a reference can provide a better understanding of the characteristics of the "Virechana"(purgative) effect of M. oleifera leaves in TCM.


Asunto(s)
Medicamentos Herbarios Chinos , Moringa oleifera , Ratones , Animales , Catárticos , Simulación del Acoplamiento Molecular , Medicamentos Herbarios Chinos/química , Estreñimiento
9.
Urol Int ; 106(9): 909-913, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34915528

RESUMEN

BACKGROUND: The aim of this study was to evaluate the clinical value of 16 G biopsy needle in transperineal template-guided prostate biopsy (TTPB), compared with 18 G biopsy needle. METHODS: The patients who underwent TTPB from August 2020 to February 2021 were randomized into 2 groups using a random number table. The control group (n = 65) and the observation group (n = 58) performed biopsy with 18 G (Bard MC l820) and 16 G (Bard MC l616) biopsy needles, respectively. Positive rate of biopsy, Gleason score, complications, and pain score were statistically analyzed. RESULTS: The age, prostate volume, PSA, and the number of cores were comparable between the 2 groups. The positive rate of biopsy in the observation group was 68.9% (40/58), meanwhile the control group was 46.2% (30/65). There was statistical difference between the 2 groups (p = 0.011). Gleason score of the observation group (8 [7-9]) was higher than that of the control group (8 [6-9]) (p = 0.038). There was no significant difference in pain score and complications including hematuria, hematospermia, perineal hematoma, infection, and urinary retention between the 2 groups (p > 0.05). CONCLUSIONS: 16 G biopsy needle significantly improved the positive rates and accurately evaluate the nature of lesions, meanwhile did not increase the incidence of complications compared with 18 G biopsy needle.


Asunto(s)
Próstata , Neoplasias de la Próstata , Biopsia , Biopsia con Aguja/efectos adversos , Humanos , Biopsia Guiada por Imagen/efectos adversos , Masculino , Dolor/etiología , Próstata/patología , Neoplasias de la Próstata/patología
10.
Nano Lett ; 21(18): 7870-7878, 2021 09 22.
Artículo en Inglés | MEDLINE | ID: mdl-34318680

RESUMEN

Fractal Pt-based materials with hierarchical structures and high self-similarity have attracted more and more attention due to their bioinspiring maximum optimization of energy utilization and mass transfer. However, their high-efficiency design of the mass- and electron-transfer still remains to be a great challenge. Herein, fractal PtPdCu hollow sponges (denoted as PtPdCu-HS) facilitating both directed mass- and electron-transfer are presented. Such directed transfer effects greatly promote electrocatalytic activity, regarded as 3.9 times the mass activity, 7.3 times the specific activity, higher poison tolerance, and higher stability than commercial Pt/C for the methanol oxidation reaction (MOR). A new "directed mass- and electron-transfer" concept, characteristics, and mechanism are proposed at the micro/nanoscale to clarify the structural design and functional enhancement of fractal electrocatalyst. This work displays new possibilities for designing novel nanomaterials with high activity and superior stability toward electrocatalysis or other practical applications.


Asunto(s)
Electrones , Fractales , Catálisis , Transporte de Electrón , Oxidación-Reducción
11.
Medicina (Kaunas) ; 58(12)2022 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-36557023

RESUMEN

Background and Objectives: To evaluate the efficacy of bladder-prostatic muscle reconstruction and bladder neck eversion anastomosis in the recovery of urinary continence after robot-assisted radical prostatectomy (RARP). Materials and Methods: From January 2020 to May 2022, 69 patients who underwent RARP in our hospital were recruited. Thirty-seven patients underwent RARP with the Veil of Aphrodite technique (control group). On the basis of the control group, 32 patients underwent bladder-prostatic muscle reconstruction and bladder neck eversion anastomosis during RARP (observation group). The recovery of urinary continence was followed up at 24 h and 1, 4, 12, and 24 weeks after catheter removal. Results: There were no significant differences in operative time (127.76 ± 21.23 min vs. 118.85 ± 24.71 min), blood loss (118.27 ± 16.75 mL vs. 110.77 ± 19.63 mL), rate of leakage (3.13% vs. 2.70%), rate of positive surgical margin (6.25% vs. 10.81%), or postoperative Gleason score [7 (6−8) vs. 7 (7−8)] between the observation group and the control group (p > 0.05). After catheter removal, the rates of urinary continence at 24 h, 1 week, 4 weeks, 12 weeks, and 24 weeks were 46.88%, 68.75%, 84.38%, 90.63%, and 93.75% in the observation group, respectively. Meanwhile, the rates of urinary continence in the control group were 21.62%, 37.84%, 62.16%, 86.49%, and 91.89%, respectively. There was a significant difference between the two groups (p = 0.034), especially at 24 h, 1 week, and 4 weeks after catheter removal (p < 0.05). Conclusions: Bladder-prostatic muscle reconstruction and bladder neck eversion anastomosis were beneficial to the recovery of urinary continence after RARP, especially early urinary continence.


Asunto(s)
Neoplasias de la Próstata , Robótica , Incontinencia Urinaria , Masculino , Humanos , Vejiga Urinaria/cirugía , Incontinencia Urinaria/etiología , Neoplasias de la Próstata/cirugía , Prostatectomía/efectos adversos , Prostatectomía/métodos , Anastomosis Quirúrgica/efectos adversos , Músculos , Resultado del Tratamiento
12.
Chemistry ; 27(57): 14142, 2021 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-34590741

RESUMEN

Invited for the cover of this issue are Xiao-Yu Yang and co-workers at Wuhan University of Technology, Heinrich-Heine-Universität Düsseldorf, University of the Witwatersrand, and Ben-Gurion University of the Negev. The image depicts Ti vacancies in TiO2 as powerful drivers of photo- and photo-electrocatalytic seawater splitting for hydrogen production. Read the full text of the article at 10.1002/chem.202101817.

13.
Chemistry ; 27(57): 14202-14208, 2021 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-34379853

RESUMEN

Photodriven seawater splitting is considered to be one of the most promising techniques for sustainable hydrogen production. However, the high salinity of seawater would deactivate catalysts and consume the photogenerated carriers. Metal vacancies in metal oxide semiconductors are critical to directed electron transfer and high salinity resistance; they are thus desirable but remain a challenge. We demonstrate a facile controllable calcination approach to synthesize TiO2 nanofibers with rich Ti vacancies with excellent photo/electro performances and long-time stability in photodriven seawater splitting, including photocatalysis and photo-electrocatalysis. Experimental measurements and theoretical calculations reveal the formation of titanium vacancies, as well as unidirectional electron trap and superior H+ adsorption ability for efficient charge transfer and resistance to corrosion by seawater. Therefore, atomic-/nanoscale characteristics and mechanism have been proposed to clarify the generation of titanium vacancies and the corresponding interfacial electron transfer.

14.
Nano Lett ; 20(5): 3122-3129, 2020 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-32343586

RESUMEN

A highly efficient photoenergy conversion is strongly dependent on the cumulative cascade efficiency of the photogenerated carriers. Spatial heterojunctions are critical to directed charge transfer and, thus, attractive but still a challenge. Here, a spatially ternary titanium-defected TiO2@carbon quantum dots@reduced graphene oxide (denoted as VTi@CQDs@rGO) in one system is shown to demonstrate a cascade effect of charges and significant performances regarding the photocurrent, the apparent quantum yield, and photocatalysis such as H2 production from water splitting and CO2 reduction. A key aspect in the construction is the technologically irrational junction of Ti-vacancies and nanocarbons for the spatially inside-out heterojunction. The new "spatial heterojunctions" concept, characteristics, mechanism, and extension are proposed at an atomic-/nanoscale to clarify the generation of rational heterojunctions as well as the cascade electron transfer.

15.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 43(2): 216-221, 2021 Apr 28.
Artículo en Zh | MEDLINE | ID: mdl-33966701

RESUMEN

Objective To analyze the CT characteristics of consolidation type of pulmonary cryptococcosis in immunocompetent patients,and thus improve the diagnosis of this disease. Methods A total of 20 cases with consolidation-type pulmonary cryptococcosis confirmed by pathological examinations were studied.Each patient underwent breath-hold multislice spiral CT,and 10 patients underwent contrast enhanced CT.The data including lesion number,lesion distribution,lesion density,performance of enhanced CT scan,accompanying signs,and prognosis were analyzed. Results The occurrence rates of single and multiple lesions were 80.0%(n=16)and 20.0%(n=4),respectively.In all the 16 multiple-lesion patients,the occurrence rate of unilateral lobar distribution was 56.0%(n=9).The 76 measurable lesions mainly presented subpleural distribution(71.1%,n=54)and lower pulmonary distribution(75.0%,n=57).A total of 39 lesions were detected in the 10 patients received contrast enhanced CT,in which 31 lesions(79.5%)showed homogeneous enhancement,34 lesions(87.2%)showed moderate enhancement,and all the lesions manifested angiogram sign.Consolidation lesions were accompanied by many CT signs,of which air bronchogram sign had the occurrence rate of 63.2%(n=48),including types Ⅲ(n =37)and Ⅳ(n=11).Other signs included halo signs(43/76,56.6%),vacuoles or cavities(9/76,11.8%),pleural thickening(14/20,70.0%),and pleural effusion(2/20,10.0%).After treatment,the lesions of 7 patients were basically absorbed and eventually existed in the form of fibrosis. Conclusions The lesions in the immunocompetent patients with consolidation type of pulmonary cryptococcosis usually occur in the lower lobe and close to the pleura,mainly presenting unilateral distribution.The CT angiogram signs,proximal air bronchogram signs,and halo signs are the main features of this disease,which contribute to the diagnosis.


Asunto(s)
COVID-19 , Criptococosis , Enfermedades Pulmonares Fúngicas , Criptococosis/diagnóstico por imagen , Humanos , Pulmón , Enfermedades Pulmonares Fúngicas/diagnóstico por imagen , Estudios Retrospectivos , Tomografía Computarizada por Rayos X
16.
Angew Chem Int Ed Engl ; 60(41): 22368-22375, 2021 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-34383376

RESUMEN

The salts {[Ln2 Ln*(Hhmq)3 (OAc)3 (hfac)2 ]+ [Ln*(hfac)3 (OAc)(MeOH)]- } (Hhmq=2-methanolquinolin-8-oxide, hfac=hexafluoroacetylacetonate; Ln, Ln*=Er, Gd, Yb) feature a discrete heteronuclear cation consisting of two types of lanthanide atoms. The quinolinoxy O-atom serves as a µ2 -bridge to two Ln atoms and as a µ3 -bridge to all three atoms, with metal⋅⋅⋅metal distances being around 3.7 Å. For 1 ([Yb2 Er]+ ), near-infrared downshifted luminescence is switched to competitive upconversion luminescence upon irradiation by a 980 nm laser under an extremely low excitation power (0.288 W cm-2 ) through introduction of fluoride ions. The stability of 1 after addition of fluoride was confirmed by powder X-ray diffraction and multistage mass spectrometry, associated with the 1 H NMR of 6 ([La2 Eu]+ ). More importantly, the at least 20-fold enhancement of the quantum yield in non-deuterated solvents at room temperature under low power densities (2 W cm-2 ) is the highest among the few molecular examples reported.

17.
J Cell Mol Med ; 24(17): 9774-9785, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32790017

RESUMEN

Previous studies revealed that caspase recruitment domain protein 9 (CARD9) was involved in severe acute pancreatitis (SAP) inflammation and that interfering with its expression in vivo could inhibit inflammation. However, the specific mechanism is unknown. This study aimed to discover the related signal pathways of CARD9 in macrophages. SiRNA interference technology was used in vivo and in vitro to detect CARD9-related signal pathways in peritoneal macrophages. Furthermore, Toll-like receptor 4 (TLR4) and membrane-associated C-type lectin-1 (Dectin-1) pathways in macrophages were activated specially to looking for the upstream signal path of CARD9. Results showed up-regulation of CARD9 expression in peritoneal macrophages of SAP rats (P < .05). CARD9 siRNA alleviated inflammatory cytokines, and inhibited the phosphorylation of NF-κB and p38MAPK in peritoneal macrophages in vivo or in vitro. Meanwhile, CARD9 siRNA reduced the concentration of CARD9 and Bcl10 in peritoneal macrophages, and TLR4 and Dectin-1 took part in CARD9 signal pathways in macrophages. In conclusion, there is an inflammation signal pathway comprised of TLR4/Dectin-1-CARD9-NF-κB/p38MAPK activated in macrophages in SAP. Blockade of CARD9 expression in macrophages can effectively alleviate SAP inflammation.


Asunto(s)
Proteínas Adaptadoras de Señalización CARD/genética , Inflamación/genética , Lectinas Tipo C/genética , Pancreatitis/genética , Receptor Toll-Like 4/genética , Animales , Proteínas Adaptadoras de Señalización CARD/antagonistas & inhibidores , Modelos Animales de Enfermedad , Regulación de la Expresión Génica/genética , Humanos , Inflamación/patología , Macrófagos/metabolismo , Macrófagos/patología , FN-kappa B/genética , Pancreatitis/patología , Peritoneo/metabolismo , Peritoneo/patología , ARN Interferente Pequeño/farmacología , Ratas , Índice de Severidad de la Enfermedad , Transducción de Señal/genética , Receptor Toll-Like 4/antagonistas & inhibidores , Proteínas Quinasas p38 Activadas por Mitógenos/genética
18.
Inorg Chem ; 59(24): 18384-18395, 2020 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-33342214

RESUMEN

Exploring excellent peroxidase mimics with enhanced peroxidase-like activity is important to the construction of a fast, low-cost, and convenient colorimetric sensing platform for heavy ions. In this work, 5,10,15,20-tetrakis(4-carboxyphenyl)porphyrin (H2TCPP) was first used to modify ZnS/CoS and make it show better peroxidase-like activity. The metal-cation vacancies generated by Hg2+ contacting H2TCPP/ZnS/CoS further stimulate the catalytic activity. It is reported that the addition of Hg2+ usually causes a decrease of the peroxidase-like activity of metal sulfides. Oppositely, in our work, Hg2+ can trigger the colorimetric signal amplification because of lots of metal-cation vacancies generated on the surface of the nanocomposites (bimetallic sulfides). The peroxidase-like activity of ZnS/CoS was evaluated by virtue of the chromogenic substrate 3,3,5,5-tetramethylbenzidine (TMB) from colorless to blue in 3 min. The enhanced catalytic activity of H2TCPP/ZnS/CoS was attributed to lots of active sites from the metal-cation defects on the surface of H2TCPP/ZnS/CoS as well as the synergistic effect of porphyrin molecules and ZnS/CoS. The adsorption behavior of H2O2 on the H2TCPP/ZnS/CoS surface with defects was studied by density functional theory calculation. Thus, a colorimetric sensing platform based on Hg2+ trigger signal amplification has been successfully constructed, which can be used to sensitively and selectively determine Hg2+ in environmental samples.


Asunto(s)
Cobalto/química , Mercurio/química , Peroxidasas/metabolismo , Porfirinas/química , Sulfuros/química , Compuestos de Zinc/química , Técnicas Biosensibles , Contaminantes Ambientales , Límite de Detección , Sustancias Macromoleculares , Imitación Molecular , Oxidación-Reducción , Peroxidasas/química
19.
Proc Natl Acad Sci U S A ; 114(39): 10350-10355, 2017 09 26.
Artículo en Inglés | MEDLINE | ID: mdl-28893981

RESUMEN

Hard coral cover on the Great Barrier Reef (GBR) is on a trajectory of decline. However, little is known about past coral mortality before the advent of long-term monitoring (circa 1980s). Using paleoecological analysis and high-precision uranium-thorium (U-Th) dating, we reveal an extensive loss of branching Acropora corals and changes in coral community structure in the Palm Islands region of the central GBR over the past century. In 2008, dead coral assemblages were dominated by large, branching Acropora and living coral assemblages by genera typically found in turbid inshore environments. The timing of Acropora mortality was found to be occasionally synchronous among reefs and frequently linked to discrete disturbance events, occurring in the 1920s to 1960s and again in the 1980s to 1990s. Surveys conducted in 2014 revealed low Acropora cover (<5%) across all sites, with very little evidence of change for up to 60 y at some sites. Collectively, our results suggest a loss of resilience of this formerly dominant key framework builder at a regional scale, with recovery severely lagging behind predictions. Our study implies that the management of these reefs may be predicated on a shifted baseline.


Asunto(s)
Antozoos/crecimiento & desarrollo , Arrecifes de Coral , Monitoreo del Ambiente/métodos , Calentamiento Global , Datación Radiométrica/métodos , Animales , Australia , Torio/química , Uranio/química
20.
Nanotechnology ; 29(34): 345402, 2018 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-29848808

RESUMEN

Polycrystalline p-type Cu1.8S composites with WSe2 nanoparticles were fabricated by the mechanical alloying method combined with the spark plasma sintering technique. The Seebeck coefficient was significantly enhanced by the optimized carrier concentration, while the thermal conductivity was simultaneously decreased due to the refined grain and WSe2 nanoparticles. An enhanced Seebeck coefficient of 110 µV K-1 and a reduced thermal conductivity of 0.68 W m-1 K-1 were obtained for the Cu1.8S + 1 wt% WSe2 sample at 773 K, resulting in a remarkably enhanced peak ZT of 1.22 at 773 K, which is 2.5 times higher than that (0.49 at 773 K) of a pristine Cu1.8S sample. The cheap and environmentally friendly Cu1.8S-based materials with enhanced properties may find promising applications in thermoelectric devices.

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