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1.
Sensors (Basel) ; 23(16)2023 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-37631805

RESUMEN

A scheme for the measurement of a microwave (MW) electric field is proposed via multi-photon coherence in Rydberg atoms. It is based on the three-photon electromagnetically induced absorption (TPEIA) spectrum. In this process, the multi-photon produces a narrow absorption peak, which has a larger magnitude than the electromagnetically induced transparency (EIT) peak under the same conditions. The TPEIA peak is sensitive to MW fields, and can be used to measure MW electric field strength. We found that the magnitude of TPEIA peaks shows a linear relationship with the MW field strength. The simulation results show that the minimum detectable strength of the MW fields is about 1/10 of that based on an common EIT effect, and the probe sensitivity could be improved by about four times. Furthermore, the MW sensing based on three-photon coherence seems to be robust against the changes in the control field and shows a broad tunability, and the scheme may be useful for designing novel MW sensing devices.

2.
J Cell Mol Med ; 25(19): 9154-9167, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34562065

RESUMEN

Accumulation of lipid droplets (LDs) induces cardiac dysfunctions in type 2 diabetes patients. Recent studies have shown that hydrogen sulphide (H2 S) ameliorates cardiac functions in db/db mice, but its regulation on the formation of LDs in cardiac tissues is unclear. Db/db mice were injected with NaHS (40 µmol·kg-1 ) for twelve weeks. H9c2 cells were treated with high glucose (40 mmol/L), oleate (200 µmol/L), palmitate (200 µmol/L) and NaHS (100 µmol/L) for 48 hours. Plasmids for the overexpression of wild-type Hrd1 and Hrd1 mutated at Cys115 were constructed. The interaction between Hrd1 and DGAT1 and DGAT2, the ubiquitylation level of DGAT1 and 2, the S-sulfhydration of Hrd1 were measured. Exogenous H2 S ameliorated the cardiac functions, decreased ER stress and reduced the number of LDs in db/db mice. Exogenous H2 S could elevate the ubiquitination level of DGAT 1 and 2 and increased the expression of Hrd1 in cardiac tissues of db/db mice. The S-sulfhydration of Hrd1 by NaHS enhanced the interaction between Hrd1 and DGAT1 and 2 to inhibit the formation of LD. Our findings suggested that H2 S modified Hrd1 S-sulfhydration at Cys115 to reduce the accumulation of LDs in cardiac tissues of db/db mice.


Asunto(s)
Sulfuro de Hidrógeno/farmacología , Gotas Lipídicas/metabolismo , Metabolismo de los Lípidos/efectos de los fármacos , Miocardio/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Animales , Biomarcadores , Diabetes Mellitus Tipo 2 , Cardiomiopatías Diabéticas/diagnóstico , Cardiomiopatías Diabéticas/etiología , Cardiomiopatías Diabéticas/metabolismo , Cardiomiopatías Diabéticas/fisiopatología , Modelos Animales de Enfermedad , Ecocardiografía , Femenino , Pruebas de Función Cardíaca , Hiperglucemia , Hiperlipidemias , Masculino , Ratones , Ratones Noqueados , Modelos Biológicos , Miocardio/patología , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/ultraestructura , Procesamiento Proteico-Postraduccional , Proteoma , Proteómica/métodos , Ubiquitina-Proteína Ligasas/genética
3.
J Cell Mol Med ; 24(16): 9362-9377, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32633463

RESUMEN

Muscle atrophy occurs in many pathological states, including cancer, diabetes and sepsis, whose results primarily from accelerated protein degradation and activation of the ubiquitin-proteasome pathway. Expression of Muscle RING finger 1 (MuRF1), an E3 ubiquitin ligase, was increased to induce the loss of muscle mass in diabetic condition. However, hydrogen sulphide (H2 S) plays a crucial role in the variety of physiological functions, including antihypertension, antiproliferation and antioxidant. In this study, db/db mice and C2C12 myoblasts treated by high glucose and palmitate and oleate were chose as animal and cellular models. We explored how exogenous H2 S attenuated the degradation of skeletal muscle via the modification of MuRF1 S-sulfhydration in db/db mice. Our results show cystathionine-r-lyase expression, and H2 S level in skeletal muscle of db/db mice was reduced. Simultaneously, exogenous H2 S could alleviate ROS production and reverse expression of ER stress protein markers. Exogenous H2 S could decrease the ubiquitination level of MYOM1 and MYH4 in db/db mice. In addition, exogenous H2 S reduced the interaction between MuRF1 with MYOM1 and MYH4 via MuRF1 S-sulfhydration. Based on these results, we establish that H2 S prevented the degradation of skeletal muscle via MuRF1 S-sulfhydration at the site of Cys44 in db/db mice.


Asunto(s)
Diabetes Mellitus Experimental/complicaciones , Diabetes Mellitus Tipo 2/complicaciones , Regulación de la Expresión Génica/efectos de los fármacos , Sulfuro de Hidrógeno/farmacología , Proteínas Musculares/metabolismo , Músculo Esquelético/efectos de los fármacos , Atrofia Muscular/prevención & control , Proteínas de Motivos Tripartitos/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Animales , Gasotransmisores/farmacología , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos , Proteínas Musculares/genética , Músculo Esquelético/metabolismo , Músculo Esquelético/patología , Atrofia Muscular/etiología , Atrofia Muscular/metabolismo , Atrofia Muscular/patología , Proteolisis , Proteínas de Motivos Tripartitos/genética , Ubiquitina-Proteína Ligasas/genética , Ubiquitinación
4.
Int J Biol Macromol ; 260(Pt 2): 129528, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38246471

RESUMEN

Ganoderma is a well-known medicinal macrofungal genus, of which several species have been thoroughly studied from the medicinal perspective, but most species are rarely involved in. In this study, we focus on the polysaccharides extracted from Ganoderma boninense and their antioxidant activity. Ganoderma boninense is a serious pathogen of oil palms that are cultivated commercially in Southeast Asia. Response surface methodology was conducted to optimize the liquid medium composition, and the mycelia biomass reached 7.063 g/L, that is, 1.4-fold compared with the seed medium. The crude and purified polysaccharides extracted from the fermentation broth showed well 1,1-diphenyl-2-picrylhydrazyl and 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid radical scavenging abilities, and the scavenging abilities of purified polysaccharides reached 94.47 % and 99.88 %, respectively. Six fractions of polysaccharides were extracted and purified from fruiting bodies, mycelia and fermentation broth separately with the elution buffers of distilled water and 0.1 M NaCl solution. Generally, the polysaccharides from fruiting bodies showed stronger protective effect on H2O2-induced HepG2 cell oxidative damage than other fractions. A total of five to seven monosaccharides were identified in the six fractions of polysaccharides. The correlation analysis revealed that the content of fucose was significantly correlated with the antioxidant activity of polysaccharides, while xylose showed negative correlation results. In summary, the polysaccharides from G. boninense have a potential to be used as natural antioxidants.


Asunto(s)
Antioxidantes , Ganoderma , Antioxidantes/farmacología , Peróxido de Hidrógeno/farmacología , Polisacáridos/farmacología
5.
Free Radic Biol Med ; 216: 118-138, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38479633

RESUMEN

Anomalous vascular endothelium significantly contributes to various cardiovascular diseases. VE-cadherin plays a vital role in governing the endothelial barrier. Krüppel-like factor 4(KLF4), as a transcription factor, which binds the VE-cadherin promoter and enhances its transcription. Tumor necrosis factor receptor-associated factor 7 (TRAF7) is an E3 ubiquitin ligase that has been shown to modulate the degradation of KLF4. H2S can covalently modify cysteine residues on proteins through S-sulfhydration, thereby influencing the structure and functionality of the target protein. However, the role of S-sulfhydration on endothelial barrier integrity remains to be comprehensively elucidated. This study aims to investigate whether protein S-sulfhydration in the endothelium regulates endothelial integrity and its underlying mechanism. In this study, we observed that protein S-sulfhydration was reduced in the endothelium during diabetes and TRAF7 was the main target. Overexpression of TRAF7-Cys327 mutant could mitigate the endothelial barrier damage by weakening TRAF7 interaction with KLF4 and reducing ubiquitination degradation of KLF4. In conclusion, our research demonstrates that H2S plays a pivotal role in regulating S-sulfhydration of TRAF7 at Cys327. This regulation effectively inhibits the ubiquitin-mediated degradation of KLF4, resulting in an upregulation of VE-cadherin levels. This molecular mechanism contributes to the prevention of endothelial barrier damage.


Asunto(s)
Diabetes Mellitus , Sulfuro de Hidrógeno , Sulfuro de Hidrógeno/farmacología , Sulfuro de Hidrógeno/metabolismo , Ubiquitinación , Regulación de la Expresión Génica , Endotelio Vascular/metabolismo , Ubiquitina/metabolismo , Diabetes Mellitus/metabolismo
6.
Biomed Pharmacother ; 160: 114200, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36750014

RESUMEN

Diabetic cardiomyopathy (DCM) is a serious complication of diabetes mellitus that eventually progresses to heart failure. The sarco(endo)plasmic reticulum calcium ATPase 2a (SERCA2a), an important calcium pump in cardiomyocytes, is closely related to myocardial systolic-diastolic function. In mammalian cells, hydrogen sulfide (H2S), as a second messenger, antioxidant, and sulfurizing agent, is involved in diverse biological processes. Despite the importance of H2S for protection against DCM, the mechanisms remain poorly understood. The aim of the present study was to determine whether H2S regulates intracellular calcium homeostasis by acting on SERCA2a to reduce cardiomyocyte apoptosis during DCM. Db/db mice were injected with NaHS for 18 weeks. Neonatal rat cardiomyocytes (NRCMs) were treated with high glucose, palmitate, oleate, and NaHS for 48 h. Compared to the NaHS-treated groups, in vivo and in vitro type 2 diabetic models both showed reduced intracellular H2S content, reduced cystathionine γ-lyase (CSE) expression, impaired cardiac function, decreased SERCA2a expression and decreased SERCA2a activity, reduced SUMOylation of SERCA2a, increased sentrin-specific protease 1 (SENP1) expression, and disruption of calcium homeostasis leading to activation of the mitochondrial apoptosis pathway. Compared to the NaHS-treated type 2 diabetes cellular model, overexpression of SENP1 C683A reduced the S-sulfhydration of SENP1, reduced the SUMOylation of SERCA2a, reduced the increased expression and activity of SERCA2a, and induced mitochondrial apoptosis in cardiomyocytes. These results suggested that exogenous H2S elevates SENP1 S-sulfhydration to increase SERCA2a SUMOylation, improve myocardial systolic-diastolic function, and decrease cardiomyocyte apoptosis in DCM.


Asunto(s)
Diabetes Mellitus Tipo 2 , Cardiomiopatías Diabéticas , Sulfuro de Hidrógeno , Animales , Ratones , Ratas , Calcio/metabolismo , Cisteína Endopeptidasas/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Cardiomiopatías Diabéticas/tratamiento farmacológico , Cardiomiopatías Diabéticas/metabolismo , Diástole , Endopeptidasas/metabolismo , Sulfuro de Hidrógeno/farmacología , Sulfuro de Hidrógeno/metabolismo , Mamíferos , Miocitos Cardíacos/metabolismo , Péptido Hidrolasas/metabolismo , Sumoilación , Sístole
7.
J Cachexia Sarcopenia Muscle ; 14(6): 2719-2732, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37899701

RESUMEN

BACKGROUND: Diabetic cardiomyopathy, a distinctive complication of diabetes mellitus, has been correlated with the presence of intracellular lipid deposits. However, the intricate molecular mechanisms governing the aberrant accumulation of lipid droplets within cardiomyocytes remain to be comprehensively elucidated. METHODS: Both obese diabetic (db/db) mice and HL-1 cells treated with 200 µmol/L palmitate and 200 µmol/L oleate were used to simulate type 2 diabetes conditions. Transmission electron microscopy is employed to assess the size and quantity of lipid droplets in the mouse hearts. Transcriptomics analysis was utilized to interrogate mRNA levels. Lipidomics and ubiquitinomics were employed to explore the lipid composition alterations and proteins participating in ubiquitin-mediated degradation in mice. Clinical data were collected from patients with diabetes-associated cardiomyopathy and healthy controls. Western blot analysis was conducted to assess the levels of proteins linked to lipid metabolism, and the biotin-switch assay was employed to quantify protein cysteine S-sulfhydration levels. RESULTS: The administration of H2 S donor, NaHS, effectively restored hydrogen sulfide levels in both the cardiac tissue and plasma of db/db mice (+7%, P < 0.001; +5%, P < 0.001). Both db/db mice (+210%, P < 0.001) and diabetic patients (+83%, P = 0.22, n = 5) exhibit elevated plasma triglyceride levels. Treatment with GYY4137 effectively lowers triglyceride levels in db/db mice (-43%, P = 0.007). The expression of cystathionine gamma-lyase and HMG-CoA reductase degradation protein 1 (SYVN1) was decreased in db/db mice compared with the wild-type mice (cystathionine gamma-lyase: -31%, P = 0.0240; SYVN1: -35%, P = 0.01), and NaHS-treated mice (SYVN1: -31%, P = 0.03). Conversely, the expression of sterol regulatory element-binding protein 1 (SREBP1) was elevated (+91%, P = 0.007; +51%, P = 0.03 compared with control and NaHS-treated mice, respectively), along with diacylglycerol O-acyltransferase 1 (DGAT1) (+95%, P = 0.001; +35%, P = 0.02) and 1-acylglycerol-3-phosphate O-acyltransferase 3 (AGPAT3) (+88%, P = 0.01; +22%, P = 0.32). Exogenous H2 S led to a reduction in lipid droplet formation (-48%, P < 0.001), restoration of SYVN1 expression, modification of SYVN1's S-sulfhydration status and enhancement of SREBP1 ubiquitination. Overexpression of SYVN1 mutated at Cys115 decreased SREBP1 ubiquitination and increased the number of lipid droplets. CONCLUSIONS: Exogenous H2 S enhances ubiquitin-proteasome degradation of SREBP1 and reduces its nuclear translocation by modulating SYVN1's cysteine S-sulfhydration. This pathway limits lipid droplet buildup in cardiac myocytes, ameliorating diabetic cardiomyopathy.


Asunto(s)
Diabetes Mellitus Tipo 2 , Cardiomiopatías Diabéticas , Animales , Humanos , Ratones , Cistationina gamma-Liasa/genética , Cistationina gamma-Liasa/metabolismo , Cisteína/metabolismo , Diabetes Mellitus Tipo 2/complicaciones , Cardiomiopatías Diabéticas/tratamiento farmacológico , Cardiomiopatías Diabéticas/genética , Cardiomiopatías Diabéticas/metabolismo , Lípidos , Proteína 1 de Unión a los Elementos Reguladores de Esteroles , Triglicéridos/metabolismo , Ubiquitina , Ubiquitina-Proteína Ligasas
8.
MycoKeys ; 86: 87-101, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35095306

RESUMEN

Auriculariales accommodates species with diverse basidiomes and hymenophores. From morphological and phylogenetic perspectives, we perform a taxonomic study on Heteroradulum, a recently validated genus within the Auriculariales. The genus Grammatus is merged into Heteroradulum, and thus its generic type G.labyrinthinus is combined with Heteroradulum and G.semis is reaccepted as a member of Heteroradulum. Heteroradulumaustraliense is newly described on the basis of three Australian specimens. Heteroradulumyunnanense is excluded from this genus and its taxonomic position at the generic level is considered uncertain. Accordingly, the circumscription of Heteroradulum is re-delimited and the concept of this genus is adjusted by including irpicoid to poroid hymenophores and a hyphal system with clamp connections or simple septa. A key to all nine accepted species of Heteroradulum is presented.

9.
Front Microbiol ; 13: 894641, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35903469

RESUMEN

Auriculariales is a fungal order with highly diverse morphological traits of basidiomes, which partially leads to a poor understanding of its taxonomic system at the generic level. To identify our recently collected specimens of Auriculariales to a species level, we perform a comprehensive phylogenetic analysis of the generic relationships in Auriculariales. In association with morphological characteristics, a new genus Alloexidiopsis belonging to Auriculariaceae is erected with two new species, namely, A. australiensis and A. schistacea. Moreover, Exidiopsis calcea separated from the generic type E. effusa and Heteroradulum niveum and H. yunnanense recently inaccurately described as members of Heteroradulum are recovered in the clade of Alloexidiopsis. These three species are thus transferred to this new genus. One collection of Exidiopsis grisea also falls in the clade of Alloexidiopsis, whereas another collection of this species is separated far from Alloexidiopsis and E. effusa. Since we have no collection to confirm the species identity of E. grisea, its generic position is uncertain. The main taxonomic morphological differences among Alloexidiopsis and related corticioid genera in Auriculariales are summarized. A key to all the five accepted species of Alloexidiopsis is provided. As two unnamed lineages exist in Alloexidiopsis besides the abovementioned five species, it is assumed that more new species will be revealed from this genus under its current circumscription.

10.
Cells ; 11(21)2022 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-36359861

RESUMEN

Hydrogen sulfide (H2S), as a gasotransmitter, is involved in various pathophysiological processes. Diabetic cardiomyopathy (DCM) is a major complication of diabetes mellitus (DM), which leads to structural and functional abnormalities of the myocardium and eventually causes heart failure (HF). Systolic and diastolic dysfunction are fundamental features of heart failure. SERCA2a, as a key enzyme for calcium transport in the endoplasmic reticulum (ER), affects the process of myocardial relaxation and contraction. H2S can protect the cardiac function against diabetic hearts, however, its mechanisms are unclear. This study found that exogenous H2S affects cellular calcium transport by regulating the H2S/MuRF1/SERCA2a/cardiac contractile pathway. Our results showed that, compared with the db/db mice, exogenous H2S restored the protein expression levels of CSE and SERCA2a, and the activity of SERCA2a, while reducing cytosolic calcium concentrations and MuRF1 expression. We demonstrated that MuRF1 could interact with SERCA2a via co-immunoprecipitation. Using LC-MS/MS protein ubiquitylation analysis, we identified 147 proteins with increased ubiquitination levels, including SERCA2a, in the cardiac tissues of the db/db mice compared with NaHS-treated db/db mice. Our studies further revealed that NaHS administration modified MuRF1 S-sulfhydration and enhanced the activity and expression of SERCA2a. Under hyperglycemia and hyperlipidemia, overexpression of the MuRF1-Cys44 mutant plasmid reduced the S-sulfhydration level of MuRF1 and decreased the ubiquitination level of SERCA2a and the intracellular Ca2+ concentration. These findings suggested that H2S modulates SERCA2a ubiquitination through MuRF1 S-sulfhydration of Cys44 to prevent decreased myocardial contractility due to increased cytosolic calcium.


Asunto(s)
Cardiomiopatías Diabéticas , Insuficiencia Cardíaca , Sulfuro de Hidrógeno , Ratones , Animales , Sulfuro de Hidrógeno/farmacología , Sulfuro de Hidrógeno/metabolismo , Calcio/metabolismo , Cromatografía Liquida , Espectrometría de Masas en Tándem , Miocardio/metabolismo , Cardiomiopatías Diabéticas/metabolismo , Ubiquitinación , Insuficiencia Cardíaca/metabolismo
11.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 2): m148, 2009 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-21581761

RESUMEN

In the title compound, [Ag(C(6)H(5)NO(2))(2)]ClO(4), the Ag(I) atom shows an almost linear coordination geometry, defined by two N atoms from two pyridine-3-carboxylic acid ligands. The complex cations are linked by hydrogen bonds between the carboxyl groups into a chain. The chains are further connected through C-H⋯O hydrogen bonds and a weak Ag⋯O inter-action [2.757 (8) Å] into a layer. Another Ag⋯O inter-action [2.899 (2) Å] and a C-H⋯O hydrogen bond connect the layers into a three-dimensional network.

12.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 3): m328-9, 2009 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-21582099

RESUMEN

The asymmetric unit of the title compound, {[AgNd(C(6)H(4)NO(2))(2)(C(2)O(4))]·2H(2)O}(n), contains one Nd(III) atom, one Ag(I) atom, one oxalate ligand, two nicotinate ligands and two uncoordinated water mol-ecules. The Nd(III) atom is eight-coordinated in a distorted square-anti-prismatic coordination geometry by four O atoms from two oxalate ligands and four O atoms from four nicotinate ligands. The Ag(I) atom has a T-shaped configuration, defined by two N atoms from two nicotinate ligands and one O atom from one oxalate ligand. The nicotinate and oxalate ligands link the Nd and Ag atoms into a three-dimensional coordination framework. O-H⋯O and O-H⋯N hydrogen bonds donated by water mol-ecules are observed in the crystal.

13.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 3): m330, 2009 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-21582100

RESUMEN

In the title mononuclear complex, [Ni(C(8)H(7)O(3))(2)(C(3)H(4)N(2))(2)], the Ni(II) atom, lying on a twofold rotation axis, is coordinated by four carboxyl-ate O atoms from two bidentate 3-hydroxy-phenylacetato ligands and two N atoms from two imidazole mol-ecules in a distorted octa-hedral geometry. A three-dimensional network is formed via inter-molecular O-H⋯O and N-H⋯O hydrogen bonds and π-π stacking inter-actions between the imidazole and benzene rings of neighboring mol-ecules [centroid-centroid distance = 3.856 (2) Å].

14.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 3): o469, 2009 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-21582140

RESUMEN

The title compound, C(22)H(24)N(4)O(4)S, adopts a trans configuration with respect to the C=N double bond. A weak intra-molecular C-H⋯N hydrogen bond is observed between the N atom of the C=N double bond and its neighboring phenyl H atom. The crystal structure is stabilized by inter-molecular C-H⋯N hydrogen bonds and C-H⋯π inter-actions.

15.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 4): o869, 2009 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-21582581

RESUMEN

In the title compound, C(26)H(25)ClN(4)O(3)S, the acyclic imine group exhibits an E configuration. The triazole ring is oriented at dihedral angles of 53.84 (2), 70.77 (1) and 32.59 (3)° with respect to the benzene rings of the 2-chloro-benzyl-idene, 4-methyl-benzyl-sulfanyl and 3,4,5-trimethoxy-phenyl groups, respectively. The crystal packing is stabilized by weak inter-molecular C-H⋯N, C-H⋯S and C-H⋯π inter-actions.

16.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 1): o37, 2008 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-21581679

RESUMEN

In the mol-ecular structure of the title compound, C(13)H(12)N(2)O(4)S(2), there is a dihedral angle of 0.41 (13)° between the benzene and thia-zole rings. In the crystal, inversion dimers linked by two C-H⋯O inter-actions together with π-π stacking between the parallel benzene rings of adjacent mol-ecules [centroid-centroid distance = 3.673 (2) Å].

17.
J Microbiol Biotechnol ; 26(1): 1-8, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26403818

RESUMEN

The new movement towards green chemistry and renewable feedstocks makes microbial production of chemicals more competitive. Among the numerous chemicals, organic acids are more attractive targets for process development efforts in the renewable-based biorefinery industry. However, most of the production costs in microbial processes are higher than that in chemical processes, among which over 60% are generated by separation processes. Therefore, the research of separation and purification processes is important for a promising biorefinery industry. This review highlights the progress of recovery processes in the separation and purification of organic acids, including their advantages and disadvantages, current situation, and future prospects in terms of recovery yields and industrial application.


Asunto(s)
Ácidos/aislamiento & purificación , Bacterias/metabolismo , Medios de Cultivo/química , Microbiología Industrial , Ácidos/metabolismo , Bacterias/genética , Bacterias/crecimiento & desarrollo , Biomasa , Medios de Cultivo/metabolismo , Fermentación , Microbiología Industrial/métodos , Microbiología Industrial/tendencias
18.
Molecules ; 10(10): 1351-7, 2005 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-18007529

RESUMEN

A facile synthesis of 3-methylthio-3-arylamino-2-cyanoacrylates from 3,3-dimethylthioacrylate and aromatic amines or amino pyridines has been achieved in moderate to high yields (64.0% ~ 93.5%) in 30 minutes at 50 degrees C under microwave irradiation. This method is very simple and the reaction conditions are mild, environmentally friendly and more importantly, quick. In the 3-(4,5-dimethylthiazol- 2-yl)-2,5-diphenyltetrazolium bromide (MTT) test, some of the title compounds were found to possess good antiproliferation activity towards PC3 cells.


Asunto(s)
Cianoacrilatos/síntesis química , Cianoacrilatos/efectos de la radiación , Microondas , Aminopiridinas/química , Compuestos de Anilina/química , Antineoplásicos/síntesis química , Antineoplásicos/farmacología , Proliferación Celular/efectos de los fármacos , Cianoacrilatos/farmacología , Evaluación Preclínica de Medicamentos , Humanos , Modelos Biológicos , Células Tumorales Cultivadas
19.
J Nanosci Nanotechnol ; 15(2): 1245-52, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26353640

RESUMEN

One-dimensional (1D) semiconductor metal oxide nanostructures have attracted increasing attention in electrochemistry, optics, magnetic, and gas sensing fields for the good properties. N-type low dimensional semiconducting oxides such as SnO2 and ZnO have been known for the detection of inflammable or toxic gases. In this paper, we fabricated the ZnO-SnO2 and SnO2 nanoparticles by hydrothermal synthesis. Microstructure characterization was performed using X-ray diffraction (XRD) and surface morphologies for both the pristine and doped samples were observed using field emission scanning electron microscope (FESEM), transmission electron microscopy (TEM) and high resolution transmission electron microscopy (HRTEM). Then we made thin film gas sensor to study the gas sensing properties of ZnO-SnO2 and SnO2 gas sensor to H2 and CO. A systematic comparison study reveals an enhanced gas sensing performance for the sensor made of SnO2 and ZnO toward H2 and CO over that of the commonly applied undecorated SnO2 nanoparticles. The improved gas sensing properties are attributed to the size of grains and pronounced electron transfer between the compound nanostructures and the absorbed oxygen species as well as to the heterojunctions of the ZnO nanoparticles to the SnO2 nanoparticles, which provide additional reaction rooms. The results represent an advance of compound nanostructures in further enhancing the functionality of gas sensors, and this facile method could be applicable to many sensing materials, offering a new avenue and direction to detect gases of interest based on composite tin oxide nanoparticles.

20.
Int J Biol Macromol ; 44(2): 121-7, 2009 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-19041888

RESUMEN

Biocompatible hydrogels based on water-soluble chitosan-ethylene glycol acrylate methacrylate (CS-EGAMA) and polyethylene glycol diamethacrylate (PEGDMA) were synthesized by photopolymerization. Characterization of morphology, weight loss, water state of hydrogel, pH-sensitivity and cytotoxicity were investigated by scanning electron microscopy (SEM), thermal gravimetric analysis (TGA), X-ray diffraction (XRD), differential scanning calorimetry (DSC), Fourier transform infrared (FTIR), swelling test and methylthiazolydiphenyl-tetrazolium bromide (MTT) assay. The results indicated that the hydrogels were sensitive to pH of the medium, no cytotoxicity for L929 and SW1353, satisfactory for the composite to be used in bioapplications.


Asunto(s)
Quitosano/química , Quitosano/síntesis química , Hidrogeles/química , Hidrogeles/síntesis química , Animales , Tampones (Química) , Rastreo Diferencial de Calorimetría , Adhesión Celular/efectos de los fármacos , Adhesión Celular/efectos de la radiación , Muerte Celular/efectos de los fármacos , Muerte Celular/efectos de la radiación , Línea Celular , Forma de la Célula/efectos de los fármacos , Forma de la Célula/efectos de la radiación , Quitosano/farmacología , Humanos , Hidrogeles/farmacología , Concentración de Iones de Hidrógeno/efectos de los fármacos , Luz , Espectroscopía de Resonancia Magnética , Ensayo de Materiales , Metacrilatos/química , Ratones , Microscopía Electrónica de Rastreo , Solubilidad/efectos de los fármacos , Solubilidad/efectos de la radiación , Solventes , Termogravimetría , Agua , Difracción de Rayos X
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