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1.
Front Microbiol ; 12: 731419, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34737727

RESUMO

Spatial organization of chemotactic proteins is important for cooperative response to external stimuli. However, factors affecting the localization dynamics of chemotaxis proteins are less studied. According to some reports, the polar localization of chemotaxis system I is induced by hypoxia and starvation in Vibrio cholerae. However, in V. cholerae, the chemotaxis system I is not involved in flagellum-mediated chemotaxis, and it may play other alternative cellular functions. In this study, we found that the polar localization of CheZ, a phosphatase regulating chemotactic movement in Azorhizobium caulinodans ORS571, can also be affected by hypoxia and cellular energy-status. The conserved phosphatase active site D165 and the C-terminus of CheZ are essential for the energy-related localization, indicating a cross link between hypoxia-related localization changes and phosphatase activity of CheZ. Furthermore, three of five Aer-like chemoreceptors containing PAS domains participate in the cellular localization of CheZ. In contrast to carbon starvation, free-living nitrogen fixation can alleviate the role of nitrogen limitation and hypoxia on polar localization of CheZ. These results showed that the localization changes induced by hypoxia might be a strategy for bacteria to adapt to complex environment.

2.
Small ; : e2103852, 2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34766728

RESUMO

Aiming at regulating and controlling the localized electronic states while maintaining the metal atoms in the isolation form, an in situ adsorbate induced strategy is proposed at a programmed temperature to activate Zr-based metal-organic framework (MOF) supported single Pd atom catalyst. It is discovered that in situ treatment environments trigger the change of lattice parameters in MOF materials by reaction heat effect, observed by in situ X-ray diffraction, spherical aberration-corrected electron microscope, and X-ray adsorption fine structure (XAFS). The as-obtained electron-deficient Pd single atoms are critical to the high intrinsic activity (turnover frequency of 0.132 s-1 ) and selectivity of 93% with the long-term stability in the semihydrogenation of acetylene, which can be comparable to the state-of-the-art Pd catalysts. This superior catalytic behavior correlates with the reduced C2 H4 desorption energy and the activation barriers for the hydrogenation, confirmed by density functional theory calculation.

3.
Environ Sci Technol ; 2021 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-34751567

RESUMO

Efficient destruction of perfluoroalkyl compounds in contaminated waters remains a challenge because of highly stable C-F bonds. In this study, mineralization of perfluorooctanoic acid (PFOA) with high concentration (∼30 mg/L) was realized in a needle-plate pulsed discharge reactor integrated with a water jet (NPDW) to which microbubbles (MBs) with different carrier gases (air, N2, and Ar) were introduced to enhance interfacial reactions. MBs effectively enrich dispersed PFOA from a bulk solution to a liquid surface to allow enhancing contact with reactive species and also expanding the plasma discharge area and channels. The PFOA removal efficiency in air and Ar discharge reached 81.5 and 95.3% in 2 h, respectively, with a defluorination ratio of no less than 50%. Energy requirements (EE/O) ranged from 216.49 to 331.95 kWh/m3. Aside from fluoride, PFOA was degraded to a range of short-chain perfluoroalkyl acids and, to a minor extent, at least 20 other fluorinated transformation products. PFOA degradation mechanisms were proposed, including decarboxylation, hydroxylation, hydrogenation reduction, and defluorination reactions. Real water matrices (groundwater, tap water, wastewater effluent, and surface water) showed moderate impact on treatment outcomes, demonstrating the robustness of the treatment process. The study demonstrated an environmentally friendly nonthermal plasma technology for effective PFOA degradation.

4.
Chem Biol Interact ; 351: 109754, 2021 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-34822792

RESUMO

Human infertility has become the third largest serious disease in the world, seriously affecting the quality of human fertility. Studies have shown that manganese (Mn) can accumulate in the testis through the blood-testicular barrier and damage the male reproductive system. However, the mechanism has not been explored clearly. Recent studies have reported that YTH domain-containing 2 (YTHDC2) can regulate reproductive function. However, none has explored the role of YTHDC2 in Mn-induced reproductive toxicity. The present study investigated whether YTHDC2/CyclinB2 (CCNB2) pathway participates in Mn-induced reproductive toxicity using Kunming mice, spermatogonia, and the seminal plasma of male workers. The mice were received intraperitoneal (i.p.) injections of 0, 12.5, 25, and 50 mg/kg MnCl2 once daily for 2 weeks. The cells were treated with 0, 100, 200 and 400 µM MnCl2 for 24 h. Here, we found that occupational Mn exposure significantly increased Mn levels in the seminal plasma of male workers, while decreased sperm density, semen quality, and the levels of YTHDC2, CCNB1, and CCNB2. We found that Mn can inhibit the YTHDC2/CCNB2 signaling pathway and block the G2/M phase of the cell cycle. Moreover, the morphology of cells and the histomorphology of mice testis were injured. Notably, over-expression (OE) of YTHDC2 increased CCNB2 levels, reduced cell cycle arrest, and improved reproductive toxicity after Mn exposure. These findings suggest that the YTHDC2/CCNB2 signaling pathway participates in Mn-induced reproductive toxicity, and OE of YTHDC2 can mitigate the toxicity of Mn.

5.
Opt Express ; 29(24): 39304-39311, 2021 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-34809297

RESUMO

Luminescent metal-organic frameworks (LMOFs) are a class of interesting and well-investigated MOF materials, which have shown remarkable prospects in the past and have been widely applied in different fields. However, due to their organic hybrid aspect, micro-/nano-patterning LMOFs in devices via a conventional semiconductor process is very challenging. In this work, we have introduced an elegant technique via nonlinear photon-chemical effect to induce the synthesis and growth of LMOFs. A facile technique for local synthesis and micro-pattering Tb-based luminescent metal organic frameworks (Tb(BTC)·G) from a solution of precursors is achieved. A single step approach micro-patterning for device integration with simultaneous chemical synthesis was proposed. Micro-devices with excellent fluorescence performance based on Tb(BTC)·G have been demonstrated. This work first suggested a high resolution bottom-up micro-patterning technique for MOF device fabrication using femtosecond laser direct writing, showing great potential on MOF based micro/nano-devices integration, especially promising for patterning high resolution luminescent MOF devices.

6.
Cell Mol Biol (Noisy-le-grand) ; 67(2): 148-154, 2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-34817324

RESUMO

Fatigue syndrome is a major health problem that affects the voluntary activities of an individual. Particularly, exercise-induced fatigue has become a serious concern in people's health. Since polysaccharides from various medicinal plants have been reported for anti-fatigue effect, the current study deals with the anti-fatigue potential of water-soluble polysaccharides of the Chinese medicinal plant Semen cassiae (Cassia obtusifolia L.) in BALB/c mice. Water-soluble polysaccharides from Semen cassiae were extracted using aqueous solvent (water). An orthogonal test design was employed for the optimization of polysaccharide extraction. The conditions optimized through this design unveiled the raw materials to solvent ratio as 1:30. The optimal temperature and time duration were found to be 80°C and 3.5 h, respectively. The yield of soluble polysaccharides at these specified conditions was 5.42%. Strikingly, the water-soluble polysaccharide from S. cassiae exhibited strong anti-fatigue activity at 100 mg/kg in BALB/c mice. S. cassiae polysaccharide extended the weight-loaded swimming duration in BALB/c mice. In addition, it ameliorated the level of antioxidant enzymes (SOD, GPX) while decreased the blood urea nitrogen, creatine phosphokinase, triglyceride, lactic acid, lactate dehydrogenase, and malondialdehyde levels in blood serum. Moreover, the assessment of the immunomodulatory effect of S. cassia polysaccharides unveiled the enhancement of B-cell and T-cell lymphocytes, denoting the positive effect on physical immunity.

7.
Artigo em Inglês | MEDLINE | ID: mdl-34836652

RESUMO

The use of semiconductors to construct heterojunctions to suppress the rapid recombination of photogenerated charges and holes is considered to be an effective way to improve the efficiency of photocatalytic hydrogen evolution. Herein, cobalt sulfide (CoSx) nanoparticles are cultivated in situ in the folds of three-dimensional flower-like nickel-aluminium layered double hydroxides (NiAl-LDHs) using a facile solvothermal method. The hydrogen production rate of the binary CoSx/NiAl-LDH heterojunction reaches 3678.59 µmol/g/h, which is 83.74 and 22 times the rates of CoSx and NiAl-LDH, respectively. The unique three-dimensional structure of NiAl-LDH facilitates the growth of CoSx and shortens the transfer pathway of photogenerated electrons. More importantly, the built-in electric field formed at the interface and the S-type charge transport mechanism caused by the bending of the energy band enhance not only charge separation but also maintain the strong oxidation ability of the holes. In this study, the newly designed S-scheme heterojunction offers a new strategy for enhancing photocatalytic water splitting.

8.
Nat Plants ; 7(11): 1505-1515, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34782772

RESUMO

Protein homoeostasis in plastids is strategically regulated by the protein quality control system involving multiple chaperones and proteases, among them the Clp protease. Here, we determined the structure of the chloroplast ClpP complex from Chlamydomonas reinhardtii by cryo-electron microscopy. ClpP contains two heptameric catalytic rings without any symmetry. The top ring contains one ClpR6, three ClpP4 and three ClpP5 subunits while the bottom ring is composed of three ClpP1C subunits and one each of the ClpR1-4 subunits. ClpR3, ClpR4 and ClpT4 subunits connect the two rings and stabilize the complex. The chloroplast Cpn11/20/23 co-chaperonin, a co-factor of Cpn60, forms a cap on the top of ClpP by protruding mobile loops into hydrophobic clefts at the surface of the top ring. The co-chaperonin repressed ClpP proteolytic activity in vitro. By regulating Cpn60 chaperone and ClpP protease activity, the co-chaperonin may play a role in coordinating protein folding and degradation in the chloroplast.

9.
J Affect Disord ; 298(Pt A): 80-85, 2021 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-34728284

RESUMO

PURPOSE: The global coronavirus disease 2019 (COVID-19) epidemic has significantly impacted people's lives. This study aimed to examine the influence of the unexpected second wave of COVID-19 on sleep quality and anxiety of Chinese residents in Beijing in June 2020, compared with the initial outbreak at the beginning of 2020, and to investigate the associated factors. METHODS: Using a web-based cross-sectional survey, we collected data from 1,511 participants. assessed with demographic information, sleep quality and anxiety symptoms. The participants were asked to compare their recent sleep and sleep during the first outbreak. The Zung's Self-rating Anxiety Scale (SAS) was used to assess their current insomnia severity. Multivariable logistic regression models were used to analyze the association between COVID-19 epidemic and risk of sleep disturbance and anxiety symptom. RESULTS: The overall prevalence of sleep disturbance and anxiety symptoms were 50.8% and 15.3% respectively. People had significantly shorter sleep duration during the second wave of COVID-19(7.3 ± 1.3) h than the first outbreak (7.5 ± 1.4)h (p < 0.001). During the second outbreak, people were less concerned about infection and more concerned about financial stress and occupational inferference. Beijing residents did not have significant differences in sleep disturbance and anxiety compared with other regions, nor were occupations and nucleic acid testing associated risk factors. Home quarantine, health administrators, history of insomnia and anxiety-depression were significantly associated with sleep disturbance. Female gender, home quarantine, history of insomnia and anxiety-depression were significantly associated with anxiety. CONCLUSION: High prevalence of sleep disturbance and depression symptom was common during the second wave of COVID-19 crisis in Beijing. Home quarantine and previous history of insomnia and anxiety-depressive risk factors were associated with sleep disturbance and anxiety. Female gender was impacting predictor of anxiety. We need continuous assessment of the sleep quality and anxiety symptoms of this epidemic.

10.
J Bacteriol ; : JB0052721, 2021 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-34843377

RESUMO

Azorhizobium caulinodans is a nitrogen-fixing bacterium that forms root nodules on its host legume, Sesbania rostrata. This agriculturally significant symbiotic relationship is important in lowland rice cultivation, and allows for nitrogen fixation under flood conditions. Chemotaxis plays an important role in bacterial colonization of the rhizosphere. Plant roots release chemical compounds that are sensed by bacteria, triggering chemotaxis along a concentration gradient toward the roots. This gives motile bacteria a significant competitive advantage during root surface colonization. Although plant-associated bacterial genomes often encode multiple chemotaxis systems, A. caulinodans appears to encode only one. The che cluster on the A. caulinodans genome contains cheA, cheW, cheY2, cheB, and cheR. Two other chemotaxis genes, cheY1 and cheZ, are located independently from the che operon. Both CheY1 and CheY2 are involved in chemotaxis, with CheY1 being the predominant signaling protein. A. caulinodans CheA contains an unusual set of C-terminal domains: a CheW-like/Receiver pair (termed W2-Rec), follows the more common single CheW-like domain. W2-Rec impacts both chemotaxis and CheA function. We found a preference for transfer of phosphoryl groups from CheA to CheY2, rather than to W2-Rec or CheY1, which appears to be involved in flagellar motor binding. Furthermore, we observed increased phosphoryl group stabilities on CheY1 compared to CheY2 or W2-Rec. Finally, CheZ enhanced dephosphorylation of CheY2 substantially more than CheY1, but had no effect on the dephosphorylation rate of W2-Rec. This network of phosphotransfer reactions highlights a previously uncharacterized scheme for regulation of chemotactic responses. IMPORTANCE Chemotaxis allows bacteria to move towards nutrients and away from toxins in their environment. Chemotactic movement provides a competitive advantage over non-specific motion. CheY is an essential mediator of the chemotactic response with phosphorylated and unphosphorylated forms of CheY differentially interacting with the flagellar motor to change swimming behavior. Previously established schemes of CheY dephosphorylation include action of a phosphatase and/or transfer of the phosphoryl group to another receiver domain that acts as a sink. Here, we propose A. caulinodans uses a concerted mechanism in which the Hpt domain of CheA, CheY2, and CheZ function together as a dual sink system to rapidly reset chemotactic signaling. To the best of our knowledge, this mechanism is unlike any that have previously been evaluated. Chemotaxis systems that utilize both receiver and Hpt domains as phosphate sinks likely occur in other bacterial species.

11.
Mol Cell Endocrinol ; : 111523, 2021 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-34843901

RESUMO

The GABAA receptor (GABAAR) plays important roles in the regulation of Mn-induced GnRH secretion in immature female rats. However, the underlying molecular mechanisms remain unknown. Here, we assessed whether FTO and its substrate m6A are correlated with GABAAR expression in GnRH neurons after treatment with Mn in vitro and in vivo. Our study indicated that Mn treatment increased the expression of GnRH mRNA and decreased the levels of GABAAR protein but had no effect on GABAAR mRNA. Moreover, Mn upregulated the levels of FTO and inhibited global cellular m6A levels and GABAAα2 mRNA m6A levels. Knockdown of FTO increased the expression of GABAAR protein and GABAAα2 mRNA m6A levels. Data from rat models further demonstrate that inhibition of FTO suppressed GABAAR protein expression in the hypothalamus, causing delayed puberty onset. Collectively, our findings suggest that FTO-dependent m6A demethylation plays a critical role in regulating GABAAR mRNA processing in GnRH neurons.

12.
BMC Cancer ; 21(1): 1282, 2021 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-34844568

RESUMO

BACKGROUND: The mean platelet volume/platelet count ratio (MPV/PC) ratio based on the preoperative peripheral MPV and PCcan be used to predict the prognosis of multiple malignant tumors. OBJECTIVE: To evaluate the prognostic value of MPV/PC in cervical cancer patients. METHODS: This study enrolled 408 patients who had undergone radical surgery for cervical cancer and evaluated the correlation of MPV/PC with patient prognosis in the primary cohort and validation cohort. Additionally, independent prognostic factors were incorporated to construct the prognostic nomogram, and the area under the receiver operating characteristic (ROC) curve (AUC) value was calculated to analyze the prognostic predictive ability of the nomogram. RESULTS: In the primary cohort, Kaplan-Meier survival analysis indicated that the overall survival (OS) for patients with MPV/PC ≤ 0.41 was significantly lower than that in patients with MPV/PC > 0.41. MPV/PC was an independent prognostic factor for resectable cervical cancer patients. Compared with neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio (PLR) or monocyte/lymphocyte ratio (MLR), the AUC values of MPV/PC in predicting the 3- and 5-year survival rates for cervical cancer patients were greater. Similar results were verified in the validation cohort. Subsequently, the nomogram constructed based on MPV/PC, International Federation of Gynecology and Obstetrics (FIGO) classification and lymphovascular invasion performed well to accurately predict the prognosis of cervical cancer patients. The 3- and 5-year survival rates predicted by the nomogram were highly consistent with the real observations. Similar results were also displayed in the validation cohort. CONCLUSIONS: MPV/PC may be used as a novel independent prognostic factor for patients with resectable cervical cancer. Compared with the FIGO classification system, the nomogram integrating MPV/PC maybe reliably predict the survival of cervical cancer patients after radical surgery.

13.
Artigo em Inglês | MEDLINE | ID: mdl-34621325

RESUMO

Objective: To evaluate the effects of electroacupuncture and moxibustion on brain-derived neurotrophic factor (BDNF) and its receptor tyrosine kinase receptor B (TrkB) protein and mRNA expressions in the colon and dorsal root ganglia of IBS rats with visceral hypersensitivity and to explore their underlying therapeutic mechanisms. Method: Forty Sprague Dawley rats were randomly divided into normal, model, model + mild moxibustion (MM), model + electroacupuncture (EA), and model + pinaverium bromide (PB) groups, with eight rats in each group. Chronic visceral hypersensitive IBS rat models were established by colorectal distension (CRD) with mustard oil clyster. Rats in the MM and EA groups, respectively, received moxibustion and electroacupuncture treatments on the Tianshu (ST25) and Shangjuxu (ST37) acupoints once daily for 7 days, and rats in the PB group received pinaverium bromide by oral gavage once daily for 7 consecutive days. After treatment, rats underwent abdominal withdrawal reflex (AWR) scoring under CRD and colon histopathological examination. Immunohistochemistry and real-time quantitative PCR (RT-qPCR) were used to study the protein and mRNA expressions of BDNF and TrkB in the rat colon and dorsal root ganglia. Results: Compared with the normal group, AWR scores and body weight were clearly increased in the model group rats (both P < 0.01). The body weights were significantly elevated (P < 0.01, P < 0.05), but the AWR scores were reduced (P < 0.05, P < 0.01), after electroacupuncture and mild moxibustion treatment. Compared with levels in normal rats, BDNF and TrkB protein and mRNA expressions were significantly elevated in the IBS model rats (P < 0.01) but were downregulated after mild moxibustion, electroacupuncture, and Western medicine treatment (P < 0.01). Conclusion: Electroacupuncture and moxibustion improved visceral hypersensitivity of IBS rats possibly by reducing BDNF and TrkB protein and mRNA expressions in the colon and dorsal root ganglia.

14.
J Tradit Chin Med ; 41(5): 789-798, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34708638

RESUMO

OBJECTIVE: To observe the effect of herb-partitioned moxibustion (HPM) on the miRNA expression profile of thyroid tissue in experimental autoimmune thyroiditis (EAT) rats. METHODS: Rats were randomly divided into normal control (NC) group, EAT model (EAT) group, HPM group and western medicine (Med) group. EAT model rats were prepared by a combined immunization with complete and incomplete Freund's adjuvant emulsified with porcine thyroglobulin and iodine. Rats in the HPM group were treated with HPM, while rats in the Med group were treated with levothyrocine (1 µg/2 mL) by gavage. HE staining was used to observe the pathological morphological changes of thyroid tissue, ELISAs was uaed to detect the serum concentrations of TGAb, TPOAb, FT3, FT4, TSH. We then performed high-throughput miRNA sequencing to analyse the miRNA expression profiles in the thyroid tissues, followed by a bioinformatics analysis. RT-qPCR was used to verify the identified differentially expressed miRNAs. RESULTS: HPM improved the thyroid tissue morphology and reduced serum TPOAb, TGAb, TSH concentration in EAT rats (P < 0.05), but with no obvious effect on FT3 and FT4 concentration. While the TSH, FT3 and FT4 concentration was significantly changed in the Med group (P < 0.01 or P < 0.05) compared with that of EAT group. Sequencing results showed that a total of 17 miRNAs were upregulated, and 4 were downregulated in the EAT rats, in which the expression levels of miR-346 and miR-331-5p were reversed by HPM. The target genes of the miRNAs that regulated by HPM were associated with a variety of immune factors and immune signals. RT-qPCR verification showed that the expression of miRNA-346 and miRNA-331-5p was consistent with the sequencing results. CONCLUSIONS: HPM could regulate the the expression of miRNA-346 and miRNA-331-5p, then act on their target genes to immune and inflammation-related pathways, which may be one of the mechanisms of HPM on EAT rats.

15.
Stroke ; 52(12): e755-e759, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34670412

RESUMO

BACKGROUND AND PURPOSE: We explored the feasibility of automated, arterial input function independent, vendor neutral prediction of core infarct, and penumbral tissue using complete and partial computed tomographic perfusion data sets through neural networks. METHODS: Using retrospective computed tomographic perfusion data from 57 patients, split as training/validation (60%/40%), we developed and validated separate 2-dimensional U-net models for cerebral blood flow (CBF) and time to maximum (Tmax) maps calculation to predict core infarct and tissue at risk, respectively. Once trained, the full sets of 28 input images were sequentially reduced to equitemporal 14, 10, and 7 time points. The averaged structural similarity index measure between the model-derived images and ground truth perfusion maps was compared. Volumes for core infarct and Tmax were compared using the Pearson correlation coefficient. RESULTS: Both CBF and Tmax maps derived using 28 and 14 time points had similar structural similarity index measure (0.80-0.81; P>0.05) when compared with ground truth images. The Pearson correlation for the CBF and Tmax volumes derived from the model using 28-tp with ground truth volumes derived from the RAPID software was 0.69 for CBF and 0.74 for Tmax. The predicted maps were fully concordant in terms of laterality to the commercial perfusion maps. The mean Dice scores were 0.54 for the core infarct and 0.63 for the hypoperfusion maps. CONCLUSIONS: Artificial intelligence model-derived volumes show good correlation with RAPID-derived volumes for CBF and Tmax. Within the constraints of a small sample size, the perfusion map quality is similar when using 14-tp instead of 28-tp. Our findings provide proof of concept that vendor neutral artificial intelligence models for computed tomographic perfusion processing using complete or partial image data sets appear feasible. The model accuracy could be further optimized using larger data sets.

16.
Inorg Chem ; 60(21): 16370-16377, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34677953

RESUMO

Three new metal-organic frameworks (MOFs), {(CH3NH3)3[Ba2(TTHA)(NO3)(H2O)2]}·2H2O (1), {(CH3NH3)4[Ba3(HTTHA)2(H2O)7]}·3H2O (2), and [Ba7(TTHA)2(NO3)2(H2O)10]·2H2O (3) (H6TTHA = 1,3,5-triazine-2,4,6-triamineh-exaacetic acid) have been synthesized and characterized. The sensing properties of 1-3 were explored with regard to volatile organic compounds (VOCs) by the quartz crystal microbalance (QCM) technique. The results indicated that 1 and 2 have a much higher selectivity and response to chloromethanes (CH2Cl2, CHCl3, and CCl4) compared with H2O, CH3OH, CH3CH2OH, CH3CN, (CH3)2CO, C6H6, C6H5CH3, C6H5CH2CH3, and C6H5Cl at room temperature. Furthermore, 1 and 2 sensing film also exhibits excellent reversibility and stability, and the response and recovery times are almost within 10 s. 3 displays a lower response and poor selectivity to the above VOCs. The significant difference may be caused by their different structural characteristics. The Ba2+ ions are all decacoordinated in 1 and 2, while Ba2+ ions have more open metal sites in 3. So, the high selectivity and response of 1 and 2 may be due to the exchange of coordination water molecules with chloromethanes and possible electrostatic effects between (CH3NH3)+ cations and chloromethanes containing more electronegative Cl atoms. DFT calculation results show that the bond energy of Ba-Cl and Ba-O is not much different, so chloromethanes at high concentrations may exchange coordination water to form weak Ba···Cl interactions and show higher response values. 3 has no obvious VOCs selectivity and higher response due to more open sites of Ba2+ ions and smaller pore size. This work develops a fast and effective method to detect chloromethanes, providing a new opportunity for designing QCM gas sensors coated with different MOF materials.

17.
Food Res Int ; 149: 110675, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34600677

RESUMO

Pharmacological and clinical studies have consistently demonstrated that polysaccharides exhibit great potential on immune regulation. Polysaccharides can interact directly or indirectly with the immune system, triggering cell-cell communication and molecular recognition, leading to immunostimulatory responses. Gut microbiota is adept at foraging polysaccharides as energy sources and confers benefits in the context of immunity and chronic autoimmune disease, such as multiple sclerosis. A compelling set of interconnectedness between the gut microbiota, natural polysaccharides, and immune regulation has emerged. In this review, we highlighted the available avenues supporting the existence of these interactions, with a focus on cytokines-mediated and SCFAs-mediated pathways. Additionally, the neuroimmune mechanisms for gut microbiota communication with the brain in multiple sclerosis are also discussed, which will lay the ground for ameliorate multiple sclerosis via polysaccharide intervention.


Assuntos
Microbioma Gastrointestinal , Esclerose Múltipla , Encéfalo , Ácidos Graxos Voláteis , Humanos , Esclerose Múltipla/tratamento farmacológico , Polissacarídeos
18.
Biomed Chromatogr ; : e5256, 2021 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-34614234

RESUMO

A method combining ultra-high-performance liquid chromatograph/quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) and chemometrics was established to evaluate the differences in chemical composition between Aconiti Lateralis Radix (Fuzi in Chinese) before and after combination with Glycyrrhizae Radix et Rhizoma (Gancao in Chinese). UPLC-Q-TOF-MS was used to characterize the chemical components before and after the combination of Fuzi with Gancao, and genetic algorithm selection variables were applied to extract important variables. Partial least square discriminant analysis was used to verify the reliability of the variables obtained by genetic algorithm selection in differentiating Fuzi and combinations with Gancao, and nine potential chemical markers were obtained. The changes in content of chemical markers in Fuzi before and after combination were visualized using a heat map and hierarchical cluster analysis. Based on the chemical markers, characteristic profiling of UPLC-Q-TOF-MS data was developed, then unsupervised principal components analysis and a supervised counter-propagation artificial neural network were used to validate the characteristic profiling approach and showed that it performed well in differentiating between Fuzi and combinations with Gancao.

19.
Front Oncol ; 11: 701539, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34490101

RESUMO

This real-world, observational study aimed to assess and compare the clinical efficacy and safety of eltrombopag with recombinant human thrombopoietin (rhTPO) in the treatment of chemotherapy induced thrombocytopenia (CIT) in patients with lymphoma. One hundred and fifty-three patients who experienced grade 3 or 4 thrombocytopenia after chemotherapy for lymphoma were enrolled, 51 of which were treated with eltrombopag, 50 with rhTPO, and 52 patients with no drug treatment were served as the control group. The lowest platelet level and mean platelet counts at Day 5, Day 7, and Day 10 were significantly higher in both the eltrombopag group (P=.041,.003,.000,.000) and rhTPO group (P=.005,.005,.000,.000) than the control, but there was no difference between treatment with eltrombopag and rhTPO. Similarly, days required for the recovery of platelet counts to ≥50×109/L and ≥75×109/L were not different between the two treatment groups but significantly higher than the control group (P <.05). Rates of bleeding and platelet transfusion were all significantly reduced in patients treated with eltrombopag (P=.031,.032) or rhTPO (P=.017,.009) when compared to the control. Treatment-related adverse events (AEs) were reported in 7 (13.7%) and 6 (12.0%) patients in the eltrombopag and rhTPO groups, respectively, all being mild and transient in nature. In conclusion, both eltrombopag and rhTPO were effective and safe in the treatment of thrombocytopenia after chemotherapy for lymphoma.

20.
Artigo em Inglês | MEDLINE | ID: mdl-34542824

RESUMO

Stroke remains a highly deadly and disabling disease with limited treatment tragedies due to the limitations of available treatments; novel therapies for stroke are needed. In this article, the synergistic results of dual bone marrow mesenchymal stem cells (BMSC) and fasudil treatment in rat models of ischemic stroke still require further identification. Sprague-Dawley rats were used to construct the middle cerebral artery, occlusion models. BMSCs were incubated with fasudil, and MTT was performed to evaluate cell proliferation. The rats were treated with fasudil + BMSC, BMSC, fasudil, and saline. Blood samples were collected for complete blood count analysis and measurement of serum TNF-α levels. The neurological functions were evaluated. After the rats were sacrificed, immunohistochemical staining and TTC staining was performed. Fasudil promoted the proliferation of BMSCs and induced their differentiation into neuron-like cells. BMSCs increased the proportion of neutrophils; nevertheless, fasudil counteracted the neutrophil increase. The TUJ-1/MAP2/VIII factor expression in the fasudil + BMSC group was significantly higher than that in the other groups. The number of GFAP-positive cells decreased in the fasudil + BMSC and BMSC alone groups. The infarct volume in the fasudil + BMSC and BMSC alone groups was significantly lower than in the fasudil alone and control groups. Both BMSCs and fasudil exert neurorestorative effects in rat models of cerebral ischemia. Fasudil neutralizes the pro-inflammatory effects of BMSCs, while BMSCs and fasudil together had synergistic effects promoting neurovascular remodeling and neurological function recovery in stroke. A combination of BMSCs and fasudil provides a promising method for the treatment of ischemic stroke.

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