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1.
Nature ; 614(7949): 694-700, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36755091

RESUMEN

The ideal electrolyte for the widely used LiNi0.8Mn0.1Co0.1O2 (NMC811)||graphite lithium-ion batteries is expected to have the capability of supporting higher voltages (≥4.5 volts), fast charging (≤15 minutes), charging/discharging over a wide temperature range (±60 degrees Celsius) without lithium plating, and non-flammability1-4. No existing electrolyte simultaneously meets all these requirements and electrolyte design is hindered by the absence of an effective guiding principle that addresses the relationships between battery performance, solvation structure and solid-electrolyte-interphase chemistry5. Here we report and validate an electrolyte design strategy based on a group of soft solvents that strikes a balance between weak Li+-solvent interactions, sufficient salt dissociation and desired electrochemistry to fulfil all the aforementioned requirements. Remarkably, the 4.5-volt NMC811||graphite coin cells with areal capacities of more than 2.5 milliampere hours per square centimetre retain 75 per cent (54 per cent) of their room-temperature capacity when these cells are charged and discharged at -50 degrees Celsius (-60 degrees Celsius) at a C rate of 0.1C, and the NMC811||graphite pouch cells with lean electrolyte (2.5 grams per ampere hour) achieve stable cycling with an average Coulombic efficiency of more than 99.9 per cent at -30 degrees Celsius. The comprehensive analysis further reveals an impedance matching between the NMC811 cathode and the graphite anode owing to the formation of similar lithium-fluoride-rich interphases, thus effectively avoiding lithium plating at low temperatures. This electrolyte design principle can be extended to other alkali-metal-ion batteries operating under extreme conditions.

2.
Environ Microbiol ; 24(9): 4382-4400, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35348272

RESUMEN

During infection, intracellular pathogens inevitably face the pressure of hypoxia. Mycobacterium tuberculosis and Mycobacterium bovis represent two typical intracellular bacteria, but the signalling pathway of their adaptation to hypoxia remains unclear. Here, we report a new mechanism of the hypoxic adaptation in M. bovis driven by the second messenger molecule c-di-GMP. We found that c-di-GMP was significantly accumulated in bacterial cells under hypoxic stress and blocked the inhibitory activity of ArgR, an arginine metabolism gene cluster regulator, which increased arginine synthesis and slowed tricarboxylic acid cycle (TCA cycle) and aerobic respiration. Meanwhile, c-di-GMP relieved the self-inhibition of argR expression, and ArgR could interact with the nitrite metabolic gene regulator Cmr, promoting the positive regulation of Cmr and, thereafter, the nitrite respiration. Consistently, c-di-GMP significantly induced the expression of arginine and nitrite metabolism gene clusters and increased the mycobacterial survival ability under hypoxia. Therefore, we found a new function of the second messenger molecule c-di-GMP and characterized ArgR as a metabolic switching regulator that can coordinate the c-di-GMP signal to trigger hypoxic adaptation in mycobacteria. Our findings provide a potential new target for blocking the life cycle of M. tuberculosis infection.


Asunto(s)
Mycobacterium bovis , Mycobacterium tuberculosis , Arginina/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , GMP Cíclico/análogos & derivados , GMP Cíclico/metabolismo , Regulación Bacteriana de la Expresión Génica , Humanos , Hipoxia/genética , Mycobacterium bovis/genética , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/metabolismo , Nitritos/metabolismo
3.
Opt Express ; 30(6): 9181-9192, 2022 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-35299353

RESUMEN

In this study, the settings of the display white points were investigated, which presented the color appearance matched with a neutral surface as observed in the state of mixed chromatic adaptation. A psychophysical experiment was conducted under 20 illumination and viewing conditions via successive binocular color matching. It is discovered that the metameric light sources have generally equivalent effects on the observers' adaptation states and the resulting white points. The correlated color temperature (CCT) of the illumination and the adapting luminance, both with a significant influence on the mixed chromatic adaptation, exhibit a positive and a negative relation to the white point CCT, respectively. The immersive illumination affects the white point through the adaptation ratio and the baseline illuminant. Finally, the experimental results were verified to be predictable with an amended mixed chromatic adaptation model, which produced a mean chromaticity error of only 0.0027 units of CIE 1976 u'v'.

4.
Nano Lett ; 21(19): 8488-8494, 2021 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-34605659

RESUMEN

Li||MoS2 solid-state batteries have higher volumetric energy density and power density than Li||Li2S batteries. However, they suffer from energy and power decay due to the formation of lithium sulfide that has low ionic/electronic conductivity and a strong Li-S bond. Herein, we overcome these challenges by incorporating the catalytic LiI-LiBr compound and carbon black into MoS2. The comprehensive simulations, characterizations, and electrochemical evaluations demonstrated that LiI-LiBr significantly reduces Li+/S2- interaction and increases the ionic conductivity of Li2S, thus enhancing the reaction kinetics and Li2S/S redox reversibility. MoS2@LiI-LiBr@C||Li cells with an areal capacity of 0.87 mAh cm-2 provide a reversible capacity of 816.2 mAh g-1 at 200 mA g-1 and maintain 604.8 mAh g-1 (based on the mass of MoS2) for 100 cycles. At a high areal capacity of 2 mAh cm-2, the battery still delivers reversible capacity of 498 mAh g-1. LiI-LiBr-carbon additive can be broadly applied for all transition-metal sulfide cathodes to enhance the cyclic and rate performance.

5.
Angew Chem Int Ed Engl ; 61(43): e202210522, 2022 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-36040840

RESUMEN

The instability of carbonate electrolyte with metallic Li greatly limits its application in high-voltage Li metal batteries. Here, a "salt-in-salt" strategy is applied to boost the LiNO3 solubility in the carbonate electrolyte with Mg(TFSI)2 carrier, which enables the inorganic-rich solid electrolyte interphase (SEI) for excellent Li metal anode performance and also maintains the cathode stability. In the designed electrolyte, both NO3 - and PF6 - anions participate in the Li+ -solvent complexes, thus promoting the formation of inorganic-rich SEI. Our designed electrolyte has achieved a superior Li CE of 99.7 %, enabling the high-loading NCM811||Li (4.5 mAh cm-2 ) full cell with N/P ratio of 1.92 to achieve 84.6 % capacity retention after 200 cycles. The enhancement of LiNO3 solubility by divalent salts is universal, which will also inspire the electrolyte design for other metal batteries.

6.
Angew Chem Int Ed Engl ; 61(26): e202202731, 2022 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-35395115

RESUMEN

The capacity of transition metal oxide cathode for Li-ion batteries can be further enhanced by increasing the charging potential. However, these high voltage cathodes suffer from fast capacity decay because the large volume change of cathode breaks the active materials and cathode-electrolyte interphase (CEI), resulting in electrolyte penetration into broken active materials and continuous side reactions between cathode and electrolytes. Herein, a robust LiF-rich CEI was formed by potentiostatic reduction of fluorinated electrolyte at a low potential of 1.7 V. By taking LiCoO2 as a model cathode, we demonstrate that the LiF-rich CEI maintains the structural integrity and suppresses electrolyte penetration at a high cut-off potential of 4.6 V. The LiCoO2 with LiF-rich CEI exhibited a capacity of 198 mAh g-1 at 0.5C and an enhanced capacity retention of 63.5 % over 400 cycles as compared to the LiF-free LiCoO2 with only 17.4 % of capacity retention.

7.
Angew Chem Int Ed Engl ; 61(49): e202214126, 2022 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-36196771

RESUMEN

Solid electrolyte interphase (SEI) formation and H2 O activity reduction in Water-in-Salt electrolytes (WiSE) with an enlarged stability window of 3.0 V have provided the feasibility of the high-energy-density aqueous Li-ion batteries. Here, we extend the cathodic potential of WiSE by rationally controlling intermolecular interaction and interphase chemistry with the introduction of trimethyl phosphate (TMP) into WiSE. The TMP not merely limits the H2 O activity via the strong interaction between TMP and H2 O but also contributes to the formation of reinforced SEI involving phosphate and LiF by manipulating the Li+ solvation structure. Thus, water-tolerance LiMn2 O4 (LMO)||Li4 Ti5 O12 (LTO) full cell with a P/N ratio of 1.14 can be assembled and achieve a long cycling life of 1000 times with high coulombic efficiency of >99.9 %. This work provides a promising insight into the cost-effective practical manufacture of LMO||LTO cells without rigorous moisture-free requirements.

8.
Angew Chem Int Ed Engl ; 61(35): e202205967, 2022 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-35789166

RESUMEN

LiNix Coy Mnz O2 (x+y+z=1)||graphite lithium-ion battery (LIB) chemistry promises practical applications. However, its low-temperature (≤ -20 °C) performance is poor because the increased resistance encountered by Li+ transport in and across the bulk electrolytes and the electrolyte/electrode interphases induces capacity loss and battery failures. Though tremendous efforts have been made, there is still no effective way to reduce the charge transfer resistance (Rct ) which dominates low-temperature LIBs performance. Herein, we propose a strategy of using low-polarity-solvent electrolytes which have weak interactions between the solvents and the Li+ to reduce Rct , achieving facile Li+ transport at sub-zero temperatures. The exemplary electrolyte enables LiNi0.8 Mn0.1 Co0.1 O2 ||graphite cells to deliver a capacity of ≈113 mAh g-1 (98 % full-cell capacity) at 25 °C and to remain 82 % of their room-temperature capacity at -20 °C without lithium plating at 1/3C. They also retain 84 % of their capacity at -30 °C and 78 % of their capacity at -40 °C and show stable cycling at 50 °C.

9.
BMC Plant Biol ; 21(1): 335, 2021 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-34261451

RESUMEN

BACKGROUND: In brown algae, dioicy is the prevalent sexual system, and phenotypic differences between male and female gametophytes have been found in many dioicous species. Saccharina japonica show remarkable sexual dimorphism in gametophytes before gametogenesis. A higher level of phenotypic differentiation was also found in female and male gametes after gametogenesis. However, the patterns of differential gene expression throughout gametophyte development and how these changes might relate to sex-specific fitness at the gamete stage in S. japonica are not well known. RESULTS: In this study, differences in gene expression between male and female gametophytes in different developmental stages were investigated using comparative transcriptome analysis. Among the 20,151 genes expressed in the haploid gametophyte generation, 37.53% were sex-biased. The abundance of sex-biased genes in mature gametophytes was much higher than that in immature gametophytes, and more male-biased than female-biased genes were observed in the mature stage. The predicted functions of most sex-biased genes were closely related to the sex-specific characteristics of gametes, including cell wall biosynthesis, sperm motility, and sperm and egg recognition. In addition, 51 genes were specifically expressed in males in both stages, showing great potential as candidate male sex-determining region (SDR) genes. CONCLUSIONS: This study describes a thorough investigation into differential gene expression between male and female gametophytes in the dioicous kelp S. japonica. A large number of sex-biased genes in mature gametophytes may be associated with the divergence of phenotypic traits and physiological functions between female gametes (eggs) and male gametes (sperm) during sexual differentiation. These genes may mainly come from new sex-biased genes that have recently evolved in the S. japonica lineage. The duplication of sex-biased genes was detected, which may increase the number of sex-biased genes after gametogenesis in S. japonica to some extent. The excess of male-biased genes over female-biased genes in the mature stage may reflect the different levels of sexual selection across sexes. This study deepens our understanding of the regulation of sex development and differentiation in the dioicous kelp S. japonica.


Asunto(s)
Células Germinativas de las Plantas/crecimiento & desarrollo , Kelp/genética , Perfilación de la Expresión Génica , Óvulo Vegetal/genética , Óvulo Vegetal/crecimiento & desarrollo , Polen/genética , Polen/crecimiento & desarrollo
10.
Angew Chem Int Ed Engl ; 60(7): 3661-3671, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33166432

RESUMEN

In carbonate electrolytes, the organic-inorganic solid electrolyte interphase (SEI) formed on the Li-metal anode surface is strongly bonded to Li and experiences the same volume change as Li, thus it undergoes continuous cracking/reformation during plating/stripping cycles. Here, an inorganic-rich SEI is designed on a Li-metal surface to reduce its bonding energy with Li metal by dissolving 4m concentrated LiNO3 in dimethyl sulfoxide (DMSO) as an additive for a fluoroethylene-carbonate (FEC)-based electrolyte. Due to the aggregate structure of NO3 - ions and their participation in the primary Li+ solvation sheath, abundant Li2 O, Li3 N, and LiNx Oy grains are formed in the resulting SEI, in addition to the uniform LiF distribution from the reduction of PF6 - ions. The weak bonding of the SEI (high interface energy) to Li can effectively promote Li diffusion along the SEI/Li interface and prevent Li dendrite penetration into the SEI. As a result, our designed carbonate electrolyte enables a Li anode to achieve a high Li plating/stripping Coulombic efficiency of 99.55 % (1 mA cm-2 , 1.0 mAh cm-2 ) and the electrolyte also enables a Li||LiNi0.8 Co0.1 Mn0.1 O2 (NMC811) full cell (2.5 mAh cm-2 ) to retain 75 % of its initial capacity after 200 cycles with an outstanding CE of 99.83 %.

11.
Angew Chem Int Ed Engl ; 60(21): 11943-11948, 2021 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-33689220

RESUMEN

Water-in-salt electrolytes (WISE) have largely widened the electrochemical stability window (ESW) of aqueous electrolytes by formation of passivating solid electrolyte interphase (SEI) on anode and also absorption of the hydrophobic anion-rich double layer on cathode. However, the cathodic limiting potential of WISE is still too high for most high-capacity anodes in aqueous sodium-ion batteries (ASIBs), and the cost of WISE is also too high for practical application. Herein, a low-cost 19 m (m: mol kg-1 ) bi-salts WISE with a wide ESW of 2.8 V was designed, where the low-cost 17 m NaClO4 extends the anodic limiting potential to 4.4 V, while the fluorine-containing salt (2 m NaOTF) extends the cathodic limiting potential to 1.6 V by forming the NaF-Na2 O-NaOH SEI on anode. The 19 m NaClO4 -NaOTF-H2 O electrolyte enables a 1.75 V Na3 V2 (PO4 )3 ∥Na3 V2 (PO4 )3 full cell to deliver an appreciable energy density of 70 Wh kg-1 at 1 C with a capacity retention of 87.5 % after 100 cycles.

12.
J Biol Chem ; 294(34): 12729-12742, 2019 08 23.
Artículo en Inglés | MEDLINE | ID: mdl-31270210

RESUMEN

Cyclic di-GMP (c-di-GMP) is an important second messenger in bacteria, and its regulatory network has been extensively studied. However, information regarding the activation mechanisms of its receptors remains limited. In this study, we characterized the two-component regulator DevR as a new c-di-GMP receptor and further uncovered a novel co-activation mechanism for effective regulation of DevR in mycobacteria. We show that high c-di-GMP levels induce the expression of the devR operon in Mycobacterium smegmatis and increase mycobacterial survival under oxidative stress. The deletion of either DevR or its two-component kinase DevS significantly weakened the stimulating effect of c-di-GMP on oxidative-stress tolerance of mycobacteria. We also found that DevR senses the c-di-GMP signal through its C-terminal structure and that c-di-GMP alone does not directly affect the DNA-binding activity of DevR. Strikingly, c-di-GMP stimulated DevR phosphorylation by the kinase DevS, thereby activating DevR's DNA-binding affinity. In summary, our results indicated that c-di-GMP triggers a phosphorylation-dependent mechanism that co-activates DevR's transcriptional activity. Our findings suggest a novel paradigm for the cross-talk between c-di-GMP signaling and two-component regulatory systems that activates transcription of stress-response genes in bacteria.


Asunto(s)
Proteínas Bacterianas/metabolismo , GMP Cíclico/análogos & derivados , Mycobacterium smegmatis/metabolismo , Estrés Oxidativo , Proteínas Bacterianas/genética , GMP Cíclico/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
13.
Cytogenet Genome Res ; 160(5): 238-244, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32659759

RESUMEN

X-linked Alport syndrome (XLAS) is a common hereditary nephropathy caused by COL4A5 gene mutations. To date, many splice site mutations have been described but few have been functionally analyzed to verify the exact splicing effects that contribute to disease pathogenesis. Here, we accidentally discovered 2 COL4A5 gene splicing mutations affecting the same residue (c.2917+1G>A and c.2917+1G>C) in 2 unrelated Chinese families. In vitro minigene assays showed that the 2 mutations produced 3 transcripts in H293T cells: one with a 96-bp deletion in exon 33, one with exon 33 skipping, and one with exon 33-34 skipping. However, fragment analysis results showed that the main splicing effects of the 2 mutations were different, the c.2917+1G>A mutation mainly activated a cryptic donor splice site in exon 33 and resulted in the deletion of 96 bp in exon 33, while the c.2917+1G>C mutation mainly caused exon 33 skipping. Our findings indicate that different nucleotide substitutions at the same residue can cause different splicing effects, which may contribute to the variable phenotype of Alport syndrome.


Asunto(s)
Empalme Alternativo/genética , Pueblo Asiatico/genética , Colágeno Tipo IV/genética , Mutación , Nefritis Hereditaria/genética , Sitios de Empalme de ARN/genética , Adulto , Línea Celular , Niño , Preescolar , Simulación por Computador , Exones/genética , Femenino , Hematuria/genética , Humanos , Masculino , Linaje , Proteinuria/genética
14.
Zhonghua Nan Ke Xue ; 26(12): 1105-1111, 2020 Dec.
Artículo en Zh | MEDLINE | ID: mdl-34898086

RESUMEN

OBJECTIVE: To investigate the clinical characteristics and pathogenic basis of a case of 46, XY disorders of sex development (DSD) and analyze the relationship of the missense mutation with the phenotype of the LHCGR gene. METHODS: We analyzed the causative gene mutation by next-generation high-throughput sequencing (HTS) and confirmed it by Sanger sequencing. We detected the effect of the mutation on the splicing function by minigene assay, evaluated its pathogenicity using the ANNOVAR mutation annotation software, and analyzed the relationship of the missense mutation and the phenotype of the LHCGR gene via literature review and data mining. RESULTS: A homozygous mutation of C.458T>C (p.Leu153Pro) was detected in the last base of exon5 of the LHCGR gene in the 46,XY DSD patient, which was a new mutation not reported previously. The mother of the patient was a heterozygous carrier of the mutation. Minigene assay indicated that c.458T>C (p.Leu153Pro) did not affect the splicing function. The mutation was shown to be pathogenic by ANNOVAR software analysis and presumed inactive, possibly affecting its binding with the ligand and leading to type-I Leydig cell hypoplasia (LCH). Literature review and data mining showed that only 19 missense mutations could cause LCH, which scattered in the LHCGR gene. CONCLUSIONS: The new mutation c.458T> C (p.Leu153Pro) of the LHCGR gene found in the 46, XY DSD patient may cause LCH by interfering with the binding function of the ligand, which has enriched the LHCGR gene mutation database and provided some reference for the studies on the LCH genotype, its phenotypic correlation and gene functions.


Asunto(s)
Trastorno del Desarrollo Sexual 46,XY , Receptores de HL , Trastorno del Desarrollo Sexual 46,XY/genética , Heterocigoto , Homocigoto , Humanos , Masculino , Mutación
15.
Angew Chem Int Ed Engl ; 59(34): 14511-14516, 2020 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-32500971

RESUMEN

P2-type layered oxides suffer from an ordered Na+ /vacancy arrangement and P2→O2/OP4 phase transitions, leading them to exhibit multiple voltage plateaus upon Na+ extraction/insertion. The deficient sodium in the P2-type cathode easily induces the bad structural stability at deep desodiation states and limited reversible capacity during Na+ de/insertion. These drawbacks cause poor rate capability and fast capacity decay in most P2-type layered oxides. To address these challenges, a novel high sodium content (0.85) and plateau-free P2-type cathode-Na0.85 Li0.12 Ni0.22 Mn0.66 O2 (P2-NLNMO) was developed. The complete solid-solution reaction over a wide voltage range ensures both fast Na+ mobility (10-11 to 10-10  cm2 s-1 ) and small volume variation (1.7 %). The high sodium content P2-NLNMO exhibits a higher reversible capacity of 123.4 mA h g-1 , superior rate capability of 79.3 mA h g-1 at 20 C, and 85.4 % capacity retention after 500 cycles at 5 C. The sufficient Na and complete solid-solution reaction are critical to realizing high-performance P2-type cathodes for sodium-ion batteries.

16.
Front Endocrinol (Lausanne) ; 15: 1397402, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38872962

RESUMEN

Graphene-based warm uterus acupoint paste (GWUAP) is an emerging non-drug alternative therapy for the treatment of primary dysmenorrhea (PD), but the underlying mechanism is still unclear. SD female rats were randomly divided into control group, model group and treatment group to explore the mechanism of GWUAP in the treatment of PD. Combined with 16S rDNA and fecal metabolomics, the diversity of microbiota and metabolites in each group was comprehensively evaluated. In this study, GWUAP reduced the torsion score of PD model rats, improved the pathological morphology of uterine tissue, reduced the pathological damage score of uterine tissue, and reversed the expression levels of inflammatory factors, pain factors and sex hormones. The 16 S rDNA sequencing of fecal samples showed that the abundance of Lactobacillus in the intestinal flora of the model group decreased and the abundance of Romboutsia increased, while the abundance of Lactobacillus in the intestinal flora of the treatment group increased and the abundance of Romboutsia decreased, which improved the imbalance of flora diversity in PD rats. In addition, 32 metabolites related to therapeutic effects were identified by metabolomics of fecal samples. Moreover, there is a close correlation between fecal microbiota and metabolites. Therefore, the mechanism of GWUAP in the treatment of PD remains to be further studied.


Asunto(s)
Puntos de Acupuntura , Dismenorrea , Metabolómica , Ratas Sprague-Dawley , Animales , Femenino , Dismenorrea/terapia , Dismenorrea/tratamiento farmacológico , Ratas , Microbioma Gastrointestinal/efectos de los fármacos , ARN Ribosómico 16S/genética , Heces/microbiología , ADN Ribosómico/genética
17.
Zhen Ci Yan Jiu ; 49(1): 37-46, 2024 Jan 25.
Artículo en Inglés, Zh | MEDLINE | ID: mdl-38239137

RESUMEN

OBJECTIVES: To investigate the effects of graphene-based warm uterus acupoint paste on uterine Toll-like receptor 4 (TLR4)/myeloid differentiation factor 88 (MyD88)/nuclear transcription factor-kappa B p65 (NF-κB p65) signaling pathway and Th1/Th2 immune balance in primary dysmenorrhea ( PD ) model rats, so as to reveal its immunological mechanisms of relieving dysmenorrhea. METHODS: Thirty SD female rats were randomly divided into 3 groups:normal group, model group and acupoint paste group, with 10 rats in each group. PD rat model was established by subcutaneous injection of estradiol benzoate for 10 consecutive days. At the same time of modeling, graphene-based warm uterus acupoint paste was applied to the acupoints of "Guanyuan" (CV4), bilateral "Zigong" (EX-CA1) and "Sanyinjiao" (SP6) of rats in the acupoint paste group. The application was continuously applied once daily for 10 d, 5 h each time. On the 11th day, oxytocin was injected intraperitoneally to observe the writhing latency, writhing times within 30 min and writhing score of rats in each group. The spleen and thymus indexes were calculated. The pathological changes of spleen and thymus tissue were observed after HE staining. The contents of serum immunoglobulin (Ig) A, IgG, tumor necrosis factor-α (TNF-α), interleukin (IL)-2, interferon-γ (IFN-γ), IL-4 and IL-10 were detected by ELISA . The protein and mRNA expression levels of TLR4, MyD88 and NF-κB p65 in rat uterine tissue were detected by Western blot and real-time quantitative PCR, respectively. RESULTS: Compared with the normal group, the writhing times and writhing scores within 30 min of rats in the model group were significantly increased(P<0.001), and the rats showed writhing reaction (P<0.01). The spleen index and thymus index were significantly decreased(P<0.01, P<0.05). The spleen and thymus had obvious pathological changes. The contents of IgA, IgG, TNF-α, IL-2 and IFN-γ in serum were significantly increased, while the contents of serum IL-4 and IL-10 were significantly decreased(P<0.001, P<0.01). The expression levels of TLR4, MyD88, NF-κB p65 protein and corresponding mRNA in uterine tissue were significantly increased(P<0.001). Following intervention, compared with the model group, the writhing latency time of rats in the acupoint paste group was prolonged, and the writhing times and writhing scores within 30 min were significantly decreased (P<0.001). The spleen index and thymus index were significantly increased(P<0.01, P<0.05). The pathological changes of spleen and thymus were improved. The contents of serum IgA, IgG, TNF-α, IL-2 and IFN-γ were significantly decreased, while the contents of IL-4 and IL-10 were significantly increased(P<0.001, P<0.05, P<0.01). The expression of TLR4, MyD88, NF-κB p65 protein and the corresponding mRNA levels in uterine tissue were decreased(P<0.001, P<0.01). CONCLUSIONS: Graphene-based warm uterus acupoint paste can regulate the immune balance of Th1/ Th2 by regulating TLR4/ MyD88/ NF-κB p65 signaling pathway, repair the pathological damage of immune tissue, improve immune function, and effectively relieve the pain symptoms of PD rats.


Asunto(s)
Dismenorrea , Grafito , Humanos , Ratas , Femenino , Animales , Ratas Sprague-Dawley , Dismenorrea/genética , Dismenorrea/terapia , FN-kappa B/genética , Factor 88 de Diferenciación Mieloide/genética , Puntos de Acupuntura , Receptor Toll-Like 4/genética , Interleucina-2 , Interleucina-10 , Factor de Necrosis Tumoral alfa , Interleucina-4 , Transducción de Señal , ARN Mensajero , Inmunidad , Inmunoglobulina A , Inmunoglobulina G
18.
ACS Appl Mater Interfaces ; 16(17): 21828-21837, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38639177

RESUMEN

Two-dimensional (2D) van der Waals materials are increasingly seen as potential catalysts due to their unique structures and unmatched properties. However, achieving precise synthesis of these remarkable materials and regulating their atomic and electronic structures at the most fundamental level to enhance their catalytic performance remain a significant challenge. In this study, we synthesized single-crystal bulk PtTe crystals via chemical vapor transport and subsequently produced atomically thin, large PtTe nanosheets (NSs) through electrochemical cathode intercalation. These NSs are characterized by a significant presence of Te vacancy pairs, leading to undercoordinated Pt atoms on their basal planes. Experimental and theoretical studies together reveal that Te vacancy pairs effectively optimize and enhance the electronic properties (such as charge distribution, density of states near the Fermi level, and d-band center) of the resultant undercoordinated Pt atoms. This optimization results in a significantly higher percentage of dangling O-H water, a decreased energy barrier for water dissociation, and an increased binding affinity of these Pt atoms to active hydrogen intermediates. Consequently, PtTe NSs featuring exposed and undercoordinated Pt atoms demonstrate outstanding electrocatalytic activity in hydrogen evolution reactions, significantly surpassing the performance of standard commercial Pt/C catalysts.

19.
Front Microbiol ; 14: 1185216, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37389346

RESUMEN

Objectives: This study aimed to identify the bacterial composition in the pancreatic fluid of severe and critical acute pancreatitis (SAP and CAP) patients. Methods: A total of 78 pancreatic fluid samples were collected from 56 SAP and CAP patients and analyze using aerobic culture and 16S rRNA gene next-generation sequencing. The clinical data of the patients were obtained from the electronic medical records. Results: Among the total 78 samples, 16S rRNA gene NGS identified a total of 660 bacterial taxa, belonging to 216 species in 123 genera. The dominant aerobic bacteria included Klebsiella pneumoniae, Acinetobacter baumannii, and Enterococcus faecium, while the dominant anaerobic bacteria included Bacteroides, Dialister invisus, and Olsenella uli. As compared to aerobic culturing, 95.96% (95/99) of the aerobic cultured bacteria were detected using the 16S rRNA gene NGS. Conclusion: The pancreatic infections in SAP and CAP patients might originate not only from the gut but also from the oral cavity and airways as well as related environments. Dynamic analysis of bacterial profile and abundance showed that some bacteria with low abundance might become the main pathogenic bacteria. There were no significant differences in the bacterial diversity between SAP and CAP.

20.
Front Med (Lausanne) ; 10: 1086756, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36968823

RESUMEN

Alport syndrome (AS) is an inherited glomerular basement membrane (GBM) disease leading to end-stage renal disease (ESRD). X-linked AS (XLAS) is caused by pathogenic variants in the COL4A5 gene. Many pathogenic variants causing AS have been detected, but the genetic modifications and pathological alterations leading to ESRD have not been fully characterized. In this study, a novel frameshift variant c.980_983del ATGG in the exon 17 of the COL4A5 gene detected in a patient with XLAS was introduced into a mouse model in by CRISPR/Cas9 system. Through biochemical urinalysis, histopathology, immunofluorescence, and transmission electron microscopy (TEM) detection, the clinical manifestations and pathological alterations of Del-ATGG mice were characterized. From 16 weeks of age, obvious proteinuria was observed and TEM showed typical alterations of XLAS. The pathological changes included glomerular atrophy, increased monocytes in renal interstitial, and the absence of type IV collagen α5. The expression of Col4a5 was significantly decreased in Del-ATGG mouse model. Transcriptomic analysis showed that differentially expressed genes (DEGs) accounted for 17.45% (4,188/24003) of all genes. GO terms indicated that the functions of identified DEGs were associated with cell adhesion, migration, and proliferation, while KEGG terms found enhanced the degradation of ECM, amino acid metabolism, helper T-cell differentiation, various receptor interactions, and several important pathways such as chemokine signaling pathway, NF-kappa B signaling pathway, JAK-STAT signaling pathway. In conclusion, a mouse model with a frameshift variant in the Col4a5 gene has been generated to demonstrate the biochemical, histological, and pathogenic alterations related to AS. Further gene expression profiling and transcriptomic analysis revealed DEGs and enriched pathways potentially related to the disease progression of AS. This Del-ATGG mouse model could be used to further define the genetic modifiers and potential therapeutic targets for XLAS treatment.

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