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1.
Water Res ; 254: 121391, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38452528

RESUMEN

Elemental sulfur-based denitrification (ESDeN) technology is known as a cost-saving alternative to its heterotrophic counterpart for nutrient removal from organic-deficient water. However, the traditional fixed-bed reactor (FixBR), as an extensively used process, suffers from a low denitrification rate and even performance deterioration during long-term operation. Herein, we proposed a novel elemental sulfur-based denitrifying moving-bed reactor (ESDeN-MovBR), in which a screw rotator was employed to drive the filled sulfur particles to be microfluidized vertically (a state of vertical-loop movement). Our results showed that the ESDeN-MovBR realized much superior and more stable denitrification performance compared to the ESDeN-FixBR, as indicated by 3.09-fold higher denitrification rate and over one order of magnitude lower intermediates (NO2- and N2O) yield, which could last for over 100 days. Further research revealed that the microfluidization of sulfur particles facilitated the expelling of nitrogen bubbles and excessive biomass, resulting in the prolongation of actual hydraulic retention time by over 80 % and could partially explain the higher denitrification rate in ESDeN-MovBR. The remaining contribution to the improvement of denitrification rate was suggested to be result from changes in biofilm properties, in which the biofilm thickness of ESDeN-MovBR was found to be 3.29 times thinner yet enriched with 2.52 times more autotrophic denitrifiers. This study offered a completely new solution to boost up the denitrification performance of ESDeN technology and provided in-depth evidence for the necessity of biofilm thickness control in such technology.


Asunto(s)
Reactores Biológicos , Desnitrificación , Azufre , Procesos Autotróficos , Nitrógeno , Nitratos
2.
Environ Sci Technol ; 57(43): 16522-16531, 2023 10 31.
Artículo en Inglés | MEDLINE | ID: mdl-37844031

RESUMEN

Reactive fillers consisting of reduced sulfur and iron species (SFe-ReFs) have received increasing attention in tertiary wastewater treatment for nitrate and phosphate coremoval. However, the existing SFe-ReFs suffer from either low performance (e.g., pyrrhotite and pyrite) or unsatisfactory use in terms of combustible risk and residual nonreactive impurities (e.g., sulfur mixing with natural iron ores). Here, we developed a new type of sulfur-siderite composite ReF (SSCReF) with a structure of natural siderite powders eventually embedded into sulfur. SSCReFs exhibited many excellent properties, including higher mechanical strengths and hardness and especially much poorer ignitability compared to pure sulfur. By using SSCReF to construct packed-bed reactors, the highest denitrification and dephosphorization rates reached 829.70 gN/m3/d (25 wt % siderite) and 36.70 gP/m3/d (75 wt % siderite), respectively. Dephosphorization was demonstrated to be dependent on sulfur-driven denitrification, in which the acid produced from the later process promoted Fe(II) dissolution, which then directly combined with phosphate to form vivianite or further converted into phosphate adsorbents (ferrihydrite, a green rust-like compound). Water flush was an effective way to finally wash out these surface deposited Fe-P compounds, as well as those nonreactive impurities (Si and Al-bearing compounds) detached from SSCReF. Such a highly efficient and safe SSCReF holds considerable application potential in secondary effluent polishing.


Asunto(s)
Desnitrificación , Nitratos , Reactores Biológicos , Azufre , Hierro , Fosfatos , Nitrógeno , Procesos Autotróficos
3.
Environ Res ; 216(Pt 3): 114649, 2023 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-36309212

RESUMEN

The nutrient supply to the freshwater system may be changed by rainfall, which also encourages the cyclic succession of microorganisms. However, in a highly dynamic land-water reservoir, the microbial metabolic changes brought on by the changes of water nutrients following rainfall are not clearly documented. The study selected the Three Gorges Reservoir (TGR) backwater region during algal bloom seasons as the study area and time, and used the Biolog-EcoPlates technique to examine the heterotrophic metabolism conditions of the water before and after rain. The field monitoring assessed how biotic and abiotic variables affected CO2 flux at the water-air interface. The tests conducted in the laboratory investigated the water-integrated metabolic process was affected by post-rainfall environmental changes. The results showed that the average flux of CO2 at the water-air interface before rainfall was -489.17 ± 506.66 mg·(m2·d)-1, while the average CO2 flux reached 393.35 ± 793.49 mg·(m2·d)-1 after rainfall. This is mostly explained by the heterotrophic metabolic variability of plankton in response to changes in the aqueous environment brought on by precipitation. These discoveries help us better understand how biological metabolisms after rain affect the CO2 flux at the water-air interface and reservoir greenhouse gas (GHG) emission equivalents can be evaluated more accurately.


Asunto(s)
Dióxido de Carbono , Plancton , Dióxido de Carbono/análisis , Eutrofización , Agua Dulce , Estaciones del Año , Agua , China , Monitoreo del Ambiente
4.
Curr Med Sci ; 42(3): 474-482, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35678907

RESUMEN

OBJECTIVE: Alzheimer's disease (AD) is the most common age-related neurodegenerative disorder. Emerging evidence suggests that synaptic dysfunction is associated with the onset and progression of AD. Interestingly, Ginkgo biloba extract (EGb) is one of the most frequently investigated herbal medicines for enhancing cognition and alleviating neurodegenerative dementia. This study aimed to investigate the effect and the mechanism of EGb on AD-like synaptic disorders. METHODS: Scopolamine (SCO)-induced rats were used to mimic AD-like memory deficits. Morris water maze test and fear conditioning test were conducted to evaluate the memory status of rats in response to different treatments. Then, the synapse alterations were assessed by Golgi staining, and Western blotting was conducted to assess the protein expression of PSD95, GluN2B, synapsin-1, and synaptophysin. Reverse transcription quantitative polymerase chain reaction was applied to detect the mRNA expression of PSD95 and the levels of miR-1-3p/miR-206-3p. RESULTS: EGb supplement alleviated the learning and memory deficits induced by SCO in behavioral experiments. Moreover, EGb treatment attenuated synaptic damage elicited by SCO, manifested as increased dendritic spine density and the proportion of mushroom-type spines in hippocampal neurons. Further investigation indicated that EGb rescued the expression of synaptic-related proteins, especially PSD95, and decreased the levels of miR-1-3p/miR-206-3p in the rat hippocampus. CONCLUSION: The application of EGb effectively treats SCO-induced memory impairments probably by suppressing miR-1-3p/miR-206-3p and elevating the expression of PSD95.


Asunto(s)
Enfermedad de Alzheimer , MicroARNs , Enfermedad de Alzheimer/metabolismo , Animales , Ginkgo biloba , Trastornos de la Memoria/inducido químicamente , Trastornos de la Memoria/tratamiento farmacológico , Extractos Vegetales , Ratas , Escopolamina/efectos adversos
5.
Acta Derm Venereol ; 102: adv00655, 2022 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-35083495

RESUMEN

Cryotherapy is one of the most common treatments for warts; however, pain during treatment and relatively high recurrence rates limit its use. Local hyperthermia has also been used successfully in the treatment of plantar warts. The aim of this study was to compare the clinical effectiveness of local hyperthermia vs cryotherapy for the treatment of plantar warts. This multi- centre, open, 2-arm, non-randomized concurrent controlled trial included 1,027 patients, who received either cryotherapy or local hyperthermia treatment. Three months after treatment, local hyperthermia and cryotherapy achieved complete clearance rates of 50.9% and 54.3%, respectively. Recurrence rates were 0.8% and 12%, respectively. Pain scores during local hyperthermia were significantly lower than for cryotherapy. Both local hyperthermia and cryotherapy demonstrated similar efficacy for clearance of plantar warts; while local hyperthermia had a lower recurrence rate and lower pain sensation during treatment.


Asunto(s)
Hipertermia Inducida , Verrugas , Crioterapia/efectos adversos , Humanos , Hipertermia Inducida/efectos adversos , Estudios Prospectivos , Resultado del Tratamiento , Verrugas/tratamiento farmacológico
6.
Org Biomol Chem ; 18(5): 956-963, 2020 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-31930235

RESUMEN

A Brønsted acid/visible-light-promoted Markovnikov hydroamination of vinylarenes with arylamines in the presence of TPT and CF3CO2H has been developed. This transformation provides a green approach to alpha-amino-substituted arylalkanes under metal-free conditions.

7.
Org Biomol Chem ; 17(29): 7042-7054, 2019 07 24.
Artículo en Inglés | MEDLINE | ID: mdl-31304502

RESUMEN

A sequential Rh(i)-catalyzed vinylation/[2 + 1]carbocyclization between enynes and diazo compounds has been developed. This transformation features a wide range of enynes and acceptor/acceptor diazo compounds, providing easy access to versatile vinyl-substituted azabicyclo[3.1.0]hexanes having a broad tolerance to functional groups.

8.
Org Lett ; 21(9): 3427-3430, 2019 05 03.
Artículo en Inglés | MEDLINE | ID: mdl-30998018

RESUMEN

A Co(II)-catalyzed pyridyl C-H bond carbenoid insertion with α-diazoacetates has been realized. This transformation features a highly regioselective C-C bond formation at the C3-position of pyridines, providing an efficient access to diverse α-aryl-α-pyridylacetates.

9.
Int J Biol Macromol ; 133: 564-574, 2019 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-31004640

RESUMEN

Dendrobium devonianum has been used as herbal medicines and nutraceutical products since ancient time in China. However, its chemical composition and pharmacological mechanisms are not fully known. In present studies, by chemical purification and characteristic identification, we discovered a novel polysaccharide from D. devonianum, which was designated as DvP-1 with molecular weights of 9.52 × 104 Da. DvP-1 is a homogeneous heteropolysaccharide consisting of D-mannose and d-glucose in the molar ration of 10.11: 1. The main glycosidic linkages were ß-1, 4-Manp, which were substituted with acetyl groups at the O-2, O-3 and/or O-6 positions. DvP-1 was found to directly stimulate the activation of macrophages in vitro, as evidenced by inducing morphologic change, thereby promoting the production of cytokines TNF-α, IL-6 and NO, and enhancing the pinocytic activity of macrophages. By establishing a zebrafish model, we also found that DvP-1 could alleviate vinorelbine-induced decrease of macrophages in vivo. Further findings indicated that DvP-1 activated macrophages through several toll-like receptors (TLRs), but mainly through TLR4. DvP-1 served as a TLR4 agonist and induced ERK, JNK, p38, and IκB-α phosphorylation, suggesting the activation of MAPK and NFκB signaling pathways downstream of TLR4. These findings could help us further understand the immunomodulating effects of D. devonianum in Chinese medicines or health foods for immunocompromised persons. They also show the medicinal value of DvP-1 for the treatment of cancer and infectious diseases caused by TLR4 dysfunction.


Asunto(s)
Dendrobium/química , Macrófagos/efectos de los fármacos , Macrófagos/inmunología , Polisacáridos/farmacología , Receptor Toll-Like 4/agonistas , Animales , Proliferación Celular/efectos de los fármacos , Citocinas/biosíntesis , Macrófagos/citología , Ratones , Monosacáridos/análisis , Polisacáridos/química , Células RAW 264.7 , Bazo/inmunología , Vinorelbina/farmacología , Pez Cebra
10.
Org Lett ; 21(8): 2804-2807, 2019 04 19.
Artículo en Inglés | MEDLINE | ID: mdl-30945872

RESUMEN

Visible-light-induced cross-coupling of arylsulfonyl azides with tertiaryamines in the presence of Eosin Y at room temperature has been achieved. This transformation features alkyl C-C bond cleavage and provides a green approach to N-sulfonylamidines under mild conditions.

11.
Food Funct ; 9(11): 6020-6028, 2018 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-30397690

RESUMEN

Lactobacillus fermentum KP-3 was isolated from Korean pickle and used to ferment ginseng. The changes in the minor ginsenosides in the fermented ginseng were analyzed and the material was evaluated in high fat diet-fed mice. Total ginsenosides increased from 0.746 mg g-1 to 0.939 mg g-1 after fermentation, and the levels of minor ginsenosides (Rg2, Rg3, Rh1, Rh2, F2, and Ro) increased from 0.186 mg g-1 to 0.704 mg g-1. In an animal study, the serum TC and LDL levels in the HFD group were significantly higher than those of the control group. Compared with the HFD group, the probiotic-fermented ginseng significantly decreased the serum TC and LDL levels. In addition, the serum and liver ALT and AST levels were dramatically increased in the HFD group, but these increases were significantly inhibited by treatment with the probiotic-fermented ginseng. Furthermore, fermented ginseng reduced high fat diet-induced liver lipid accumulation. Overall, fermentation with L. fermentum KP-3 enhanced minor ginsenosides in ginseng and this probiotic-fermented ginseng ameliorated hyperlipidemia and liver injury induced by a high fat diet.


Asunto(s)
Ginsenósidos/farmacología , Hiperlipidemias/tratamiento farmacológico , Limosilactobacillus fermentum/metabolismo , Hepatopatías/tratamiento farmacológico , Panax/química , Alanina Transaminasa/sangre , Animales , Aspartato Aminotransferasas/sangre , Glucemia/metabolismo , Colesterol/sangre , Dieta Alta en Grasa , Fermentación , Microbiología de Alimentos , Hiperlipidemias/sangre , Hígado/efectos de los fármacos , Hígado/metabolismo , Hepatopatías/sangre , Masculino , Ratones , Ratones Endogámicos C57BL , Extractos Vegetales/farmacología , Probióticos , Triglicéridos/sangre
12.
Biochem Biophys Res Commun ; 443(4): 1182-8, 2014 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-24393841

RESUMEN

Multipotent human bone marrow stromal cells (hBMSCs) potentially serve as a source for cell-based therapy in regenerative medicine. However, in vitro expansion was inescapably accompanied with cell senescence, characterized by inhibited proliferation and compromised pluripotency. We have previously demonstrated that this aging process is closely associated with reduced 20S proteasomal activity, with down-regulation of rate-limiting catalytic ß-subunits particularly evident. In the present study, we confirmed that proteasomal activity directly contributes to senescence of hBMSCs, which could be reversed by overexpression of the ß5-subunit (PSMB5). Knocking down PSMB5 led to decreased proteasomal activity concurrent with reduced cell proliferation in early-stage hBMSCs, which is similar to the senescent phenotype observed in late-stage cells. In contrast, overexpressing PSMB5 in late-stage cells efficiently restored the normal activity of 20S proteasomes and promoted cell growth, possibly via upregulating the Cyclin D1/CDK4 complex. Additionally, PSMB5 could enhance cell resistance to oxidative stress, as evidenced by the increased cell survival upon exposing senescent hBMSCs to hydrogen peroxide. Furthermore, PSMB5 overexpression retained the pluripotency of late-stage hBMSCs by facilitating their neural differentiation both in vitro and in vivo. Collectively, our work reveals a critical role of PSMB5 in 20S proteasome-mediated protection against replicative senescence, pointing to a possible strategy for maintaining the integrity of culture-expanded hBMSCs by manipulating the expression of PSMB5.


Asunto(s)
Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/metabolismo , Complejo de la Endopetidasa Proteasomal/genética , Complejo de la Endopetidasa Proteasomal/metabolismo , Animales , Diferenciación Celular/genética , Diferenciación Celular/fisiología , Proliferación Celular , Supervivencia Celular/genética , Supervivencia Celular/fisiología , Senescencia Celular/genética , Senescencia Celular/fisiología , Ciclina D1/metabolismo , Quinasa 4 Dependiente de la Ciclina/metabolismo , Técnicas de Silenciamiento del Gen , Humanos , Ratones , Ratones Endogámicos BALB C , Estrés Oxidativo , Regulación hacia Arriba
13.
Biochem Biophys Res Commun ; 422(1): 121-7, 2012 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-22564728

RESUMEN

Human bone marrow stromal cells (hBMSCs) could be used in clinics as precursors of multiple cell lineages following proper induction. Such application is impeded by their characteristically short lifespan, together with the increasing loss of proliferation capability and progressive reduction of differentiation potential after the prolonged culture expansion. In the current study, we addressed the possible role of 20S proteasomes in this process. Consistent with prior reports, long-term in vitro expansion of hBMSCs decreased cell proliferation and increased replicative senescence, accompanied by reduced activity and expression of the catalytic subunits PSMB5 and PSMB1, and the 20S proteasome overall. Application of the proteasome inhibitor MG132 produced a senescence-like phenotype in early passages, whereas treating late-passage cells with 18α-glycyrrhetinic acid (18α-GA), an agonist of 20S proteasomes, delayed the senescence progress, enhancing the proliferation and recovering the capability of differentiation. The data demonstrate that activation of 20S proteasomes assists in counteracting replicative senescence of hBMSCs expanded in vitro.


Asunto(s)
Células Madre Adultas/citología , Células de la Médula Ósea/citología , Senescencia Celular , Células Madre Multipotentes/citología , Complejo de la Endopetidasa Proteasomal/fisiología , Células del Estroma/citología , Células Madre Adultas/enzimología , Células de la Médula Ósea/enzimología , Diferenciación Celular , Proliferación Celular , Células Cultivadas , Inhibidores de Cisteína Proteinasa/farmacología , Humanos , Leupeptinas/farmacología , Células Madre Multipotentes/enzimología , Inhibidores de Proteasoma , Células del Estroma/enzimología
14.
Zhonghua Nan Ke Xue ; 11(12): 912-4, 917, 2005 Dec.
Artículo en Chino | MEDLINE | ID: mdl-16398362

RESUMEN

OBJECTIVE: To analyse sonographical features of epididymis tuberculosis with caseous necrosis and improve the accuracy of ultrasonic diagnosis. METHODS: Ultrasonic features of 12 cases with epididymis tuberculosis with caseous necrosis, confirmed by surgical pathology, was retrospectively analysed: size, location, echogenicity, degree of blood flow in the lesion. RESULTS: In all 12 patients, the number of purified protein derivative test (PPD) presenting the positive reached to 67%, while cases with the pulmonary tuberculosis was 42%. The epididymal tuberculosis with caseous necrosis could present images of the whole or focal epididymal enlargement and abnormal shape. The lesions internal echoes were irregular, inhomogeneous increased isoechoic echogenicity or hypoechoic, including bad-defined, irregular, homogeneous hypoechoic or anechoic. In lesional location, 4 out of 12 patients (33%) possessed richly color blood flow in Color Doppler Power Imaging(CDPI). The testicular enlargement with increased internal echoes and the testicular hydroceles were partly (58%, 7/12) observed by ultrasound. There was no varicocele, scrotal wall thickening and inguinal lymph node enlargement. CONCLUSION: The High Frequency Color Doppler images is helpful for the diagnosis and differential diagnosis of epididymis tuberculosis with caseous necrosis.


Asunto(s)
Epididimitis/diagnóstico por imagen , Tuberculosis de los Genitales Masculinos/diagnóstico por imagen , Adulto , Diagnóstico Diferencial , Epididimitis/patología , Humanos , Masculino , Persona de Mediana Edad , Necrosis , Estudios Retrospectivos , Tuberculosis de los Genitales Masculinos/patología , Ultrasonografía Doppler en Color
15.
National Journal of Andrology ; (12): 912-917, 2005.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-339396

RESUMEN

<p><b>OBJECTIVE</b>To analyse sonographical features of epididymis tuberculosis with caseous necrosis and improve the accuracy of ultrasonic diagnosis.</p><p><b>METHODS</b>Ultrasonic features of 12 cases with epididymis tuberculosis with caseous necrosis, confirmed by surgical pathology, was retrospectively analysed: size, location, echogenicity, degree of blood flow in the lesion.</p><p><b>RESULTS</b>In all 12 patients, the number of purified protein derivative test (PPD) presenting the positive reached to 67%, while cases with the pulmonary tuberculosis was 42%. The epididymal tuberculosis with caseous necrosis could present images of the whole or focal epididymal enlargement and abnormal shape. The lesions internal echoes were irregular, inhomogeneous increased isoechoic echogenicity or hypoechoic, including bad-defined, irregular, homogeneous hypoechoic or anechoic. In lesional location, 4 out of 12 patients (33%) possessed richly color blood flow in Color Doppler Power Imaging(CDPI). The testicular enlargement with increased internal echoes and the testicular hydroceles were partly (58%, 7/12) observed by ultrasound. There was no varicocele, scrotal wall thickening and inguinal lymph node enlargement.</p><p><b>CONCLUSION</b>The High Frequency Color Doppler images is helpful for the diagnosis and differential diagnosis of epididymis tuberculosis with caseous necrosis.</p>


Asunto(s)
Adulto , Humanos , Masculino , Persona de Mediana Edad , Diagnóstico Diferencial , Epididimitis , Diagnóstico por Imagen , Patología , Necrosis , Estudios Retrospectivos , Tuberculosis de los Genitales Masculinos , Diagnóstico por Imagen , Patología , Ultrasonografía Doppler en Color
16.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-683426

RESUMEN

Objective To investigate the expression of glucocorticoid receptor-alpha and beta(GR?and GR?)mRNA of peripheral blood mononuclear cells(PBMCs)in patients with dermatomyositis/polymyositis (DM/PM)and analyze their association with the pathogenesis and clinical response to glucocorticoid therapy. Methods The expression of GR?and GR?mRNA in PBMCs from 20 normal controls and 36(24 steroid- sensitive,12 steroid-resistant)patients with DM/PM were detected by reverse transcription polymerase chain reaction(RT-PCR).Results Compared to normal controls,the expression of GR?mRNA in the DM/PM was significantly decreased(P

17.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-683034

RESUMEN

0.05).But GR number[sites/cell]and the expression of GR mRNA in PBMCs from PM/DM was significantly lower than those in healthy controls(P

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