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1.
J Environ Manage ; 301: 113859, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34597949

RESUMO

In order to strengthen the treatment of low-concentration ammonia nitrogen wastewater at low temperature, iron-loaded activated carbon (Fe-AC) with ultrasonic impregnation method was used as the filter material of biofilter process. The performance and mechanism of ammonia nitrogen removal from simulated secondary wastewater by iron-loaded biological activated carbon filter (Fe-BACF) were studied at 10 °C. The characterization results showed that iron was loaded on the surface of AC in the form of Fe2O3, and the specific surface area, total pore volume, pore size and alkaline functional group content of Fe-AC were obviously increased. After the formation of biofilm on the surface of filter media, the average removal rate of ammonia nitrogen by Fe-BACF (97.9%) was significantly higher than that of conventional BACF (87.8%). The improved surface properties increased the number and metabolic activity of microorganisms, and promoted the secretion of EPS on the surface of Fe-BAC. The results of high-throughput sequencing showed that the existence of Fe optimized the bacterial community structure on the surface of Fe-BAC, with the increase of the abundances of psychrophilic bacteria and ammonia nitrogen removal bacteria. The mechanism of enhanced ammonia nitrogen removal by Fe-BACF was the joint action of many factors, among which the main causal relationship was that modification of iron could optimize the number and category of microorganisms on Fe-BAC surface by improving the surface properties, thus improving the biological nitrogen removal ability. Results of this study provided a practical way for the treatment of low ammonia nitrogen wastewater in cold regions.


Assuntos
Amônia , Águas Residuárias , Amônia/análise , Reatores Biológicos , Carvão Vegetal , Desnitrificação , Filtração , Ferro , Nitrogênio/análise , Temperatura
2.
Dev Comp Immunol ; 127: 104270, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34582881

RESUMO

Clostridium perfringens (C. perfringens) type C (CPC) is one of the chief pathogens that causes diarrhea in piglets, and C. perfringens beta2 (CPB2) toxin is the main virulence factor of CPC. Our previous research demonstrated that ssc-microR-132 was differentially expressed in ileal tissues of CPC-mediated diarrheic piglets and healthy piglets, which implied a potential role of ssc-microR-132 in this process. Here, we found that ssc-microR-132 was notably down-regulated in CPB2-exposed intestinal porcine epithelial cells (IPEC-J2), which was consistent with the ileal tissue expression. Moreover, ssc-microR-132 upregulation alleviated CPB2-induced inflammatory damage and apoptosis in IPEC-J2, whereas ssc-microR-132 knockdown presented the opposite effects. Furthermore, the dual-luciferase reporter assay indicated that ssc-microR-132 directly targeted Dachshund homolog 1 (DACH1). Moreover, DACH1 overexpression intensified CPB2-induced inflammatory injury and apoptosis in IPEC-J2. Remarkably, the introduction of DACH1 weakened the anti-inflammatory and anti-apoptotic effects of ssc-microR-132 in CPB2-exposed IPEC-J2. Overall, the results reveal that ssc-microR-132 targeted DACH1 to alleviate CPB2-mediated inflammation and apoptosis in IPEC-J2.

3.
Cell Death Dis ; 12(11): 1080, 2021 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-34775498

RESUMO

Protein arginine methyltransferase 1 (PRMT1) is able to promote breast cancer cell proliferation. However, the detailed mechanisms of PRMT1-mediated breast cancer cell proliferation are largely unknown. In this study, we reveal that PRMT1-mediated methylation of EZH2 at the R342 site (meR342-EZH2) has a great effect on PRMT1-induced cell proliferation. We also demonstrate that meR342-EZH2 can accelerate breast cancer cell proliferation in vitro and in vivo. Further, we show that meR342-EZH2 promotes cell cycle progression by repressing P16 and P21 transcription expression. In terms of mechanism, we illustrate that meR342-EZH2 facilitates EZH2 binding with SUZ12 and PRC2 assembly by preventing AMPKα1-mediated phosphorylation of pT311-EZH2, which results in suppression of P16 and P21 transcription by enhancing EZH2 expression and H3K27me3 enrichment at P16 and P21 promoters. Finally, we validate that the expression of PRMT1 and meR342-EZH2 is negatively correlated with pT311-EZH2 expression. Our findings suggest that meR342-EZH2 may become a novel therapeutic target for the treatment of breast cancer.

4.
Opt Express ; 29(21): 34166-34174, 2021 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-34809213

RESUMO

Broadband emission was obtained over 2.6 to 4.1 µm (Pr3+: 1G4→3F4, 3F3) in AlF3-based glass samples doped with different concentrations of praseodymium and 1 mol% ytterbium using a 976 nm laser pump. An efficient energy transfer process from Yb3+: 2F5/2 to Pr3+: 1G4 was analyzed through emission spectra and fluorescence lifetime values. The absorption and emission cross-sections were calculated by Füchtbauer-Ladenburg and McCumber theories and a positive gain can be obtained when P>0.3. To the best of the authors' knowledge, this work represents the first report of broadband mid-infrared emission of Pr3+ in an AlF3-based glass. The results show that praseodymium doped AlF3-based glass sensitized by ytterbium could be a promising candidate for fiber lasers operating in mid-infrared region.

5.
J Surg Res ; 271: 24-31, 2021 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-34814049

RESUMO

BACKGROUND: To delineate the clinical characteristics of intestinal fistula patients with Bloodstream infection (BSI). METHODS: Retrospective case series in Surgical Intensive Care Unit (SICU), Shanghai Ninth People's Hospital, Shanghai JiaoTong University School of Medicine, Shanghai, China. Among a cohort of 204 patients with a diagnosis of intestinal fistula, 46 who were complicated with BSI were analysed retrospectively. Data was collected from January 1, 2018 to February 1, 2020. RESULTS: Among the 204 patients with intestinal fistula, 46 patients showed positive blood cultures, which clearly had BSIs. Parenteral nutrition (PN) time (OR 1.08, 95% CI 1.04∼1.12, P < 0.01), transferred from external ICU (OR 3.68, 95% CI 1.48∼9.17, P = 0.01), septic shock (OR 4.61, 95% CI 1.77∼11.97, P < 0.01), APACHE II (OR 1.11, 95% CI 1.01∼1.22, P = 0.04) were significantly associated with BSI in patients with intestinal fistula. When APACHE II score exceeds 12.0 points or PN time exceeds 18.0 D, the chance of BSI in patients with intestinal fistula increases significantly. In addition, compared with the non-BSI group, BSI group had a higher mortality and expenses in ICU, longer stay in ICU and total hospital stay, and worse quality of life (all P < 0.05). A total of 105 isolates from samples (including sputum, pus and blood) of 46 patients in the BSI group, among which were mainly gram negative rods and fungi, as well as blood isolates. Importantly, in patients with intestinal fistula, BSIs caused by fungi accounted for 23.4%. CONCLUSION: Long-term PN, transfer from external ICU, septic shock, and higher APACHE II scores are often associated with an increased probability of BSIs in patients with intestinal fistula and a higher mortality. Gram-negative bacteria are the main pathogenic bacteria in intestinal fistula patients with BSI, and patients with intestinal fistula are more likely to develop fungal BSIs.

6.
Front Nutr ; 8: 706552, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34805238

RESUMO

Northwest China has one of the most vulnerable agricultural systems in the context of global climate change. We argue that sustainable agriculture development in this region requires a systematic approach toward climate change adaptation, and propose a schematic framework for strategic thinking. We first briefly review the impacts of climate change on various agricultural environmental factors, including light, temperature, water, and atmosphere, and explores the effects of climate change on agricultural practices, such as disaster response, pests and weeds control, fertilizer application, and species selection. The study shows that climate change has increased extreme climate disasters such as drought and heat waves, and has expanded the scope and severity of pests and weeds, which in turn requires a series of changes in farming practices. These effects have profound impacts on farmland management, as well as the sustainability of the agricultural system. Based on the findings, the authors argue that the key adaptation strategies should include: (1) optimizing the geographic distribution of agriculture, (2) cultivating new crop varieties that can better adapt to the changing environment, (3) adjusting cropping timing and structure, (4) developing water-saving irrigation systems, (5) improving capacities of disaster prevention and mitigation at both household and government levels, and (6) strengthening the sciences, technology, and human resources to mitigate the adverse effects of climate change.

7.
Sci Total Environ ; : 151804, 2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34808186

RESUMO

Arsenic (As) transformation by human gut microbiota has been evidenced to impact As toxicity and human health. However, little is known about the influence of gut microbiota on As bioavailability from incidental ingestion of soil. In this study, we assessed As relative bioavailability (RBA) using an in vivo mouse model and As bioaccessibility in the colon phase of in vitro assays. Strong in vivo-in vitro correlations (R2 = 0.70-0.92, P < 0.05) were observed between soil As RBA (10.2%-57.7%) and colon bioaccessibility (4.8%-49.0%) in 13 As-contaminated soils. Upon in vitro incubation of human colon microbiota, we found a high degree of As transformation and 65.9% of generated As(III) was observed in soil residues. For in vivo mouse assay, DMA(V) accounted for 79.0% of cumulative urinary As excretion. Except for As(V), dominant As species including As(III), DMA(V) and As sulfides were also detected in mouse feces. Gut bacteria (families Rikenellaceae and Marinifilaceae) could be significantly correlated with As intake and excretion in mice (P < 0.05). Our findings provide evidence that gut microbiota can affect transformation, bioavailability, and fate of the orally ingested soil As in human gastrointestinal tract.

8.
Opt Express ; 29(24): 40072-40090, 2021 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-34809357

RESUMO

Foveated imaging, which has the ability to provide overall situational awareness over a large field of view and high-resolution perception of local details, has significant advantages in many specific applications. However, existing artificially foveated imaging systems are complex, bulky, and expensive, and the flexibility of the fovea specifically has many limitations. To overcome these deficiencies, this paper proposes a method for foveated imaging by collecting multiple partially overlapping sub-fields of view. To capture the above special sub-fields of view, we propose a high-efficiency algorithm based on the characteristics of the field of view deflected by the Risley-prism and aimed at solving the prism rotation angles. In addition, we prove the reliability of the proposed algorithm by cross-validation with the particle swarm optimization algorithm. The experimental results show that the proposed method can achieve flexible foveated imaging using a single Risley-prism imaging system.

9.
Proc Natl Acad Sci U S A ; 118(48)2021 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-34810250

RESUMO

Arising from reduced dielectric screening, excitonic effects should be taken into account in ultrathin two-dimensional photocatalysts, and a significant challenge is achieving nontrivial excitonic regulation. However, the effect of structural modification on the regulation of the excitonic aspect is at a comparatively early stage. Herein, we report unusual effects of surface substitutional doping with Pt on electronic and surface characteristics of atomically thin layers of Bi3O4Br, thereby enhancing the propensity to generate 1O2 Electronically, the introduced Pt impurity states with a lower energy level can trap photoinduced singlet excitons, thus reducing the singlet-triplet energy gap by ∼48% and effectively facilitating the intersystem crossing process for efficient triplet excitons yield. Superficially, the chemisorption state of O2 causes the changes in the magnetic moment (i.e., spin state) of O2 through electron-mediated triplet energy transfer, resulting a spontaneous spin-flip process and highly specific 1O2 generation. These traits exemplify the opportunities that the surface engineering provides a unique strategy for excitonic regulation and will stimulate more research on exciton-triggering photocatalysis for solar energy conversion.

10.
IEEE Access ; 9: 20208-20222, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34812377

RESUMO

In order to solve the problem of cross-regional customized bus (CB) route planning during the COVID-19, we develop a CB route planning method based on an improved Q-learning algorithm. First, we design a sub-regional route planning approach considering commuters' time windows of pick-up stops and drop-off stops. Second, for the CB route with the optimal social total travel cost, we improve the traditional Q-learning algorithm, including state-action pair, reward function and update rule of Q value table. Then, a setup method of CB stops is designed and the path impedance function is constructed to obtain the optimal operating path between each of the two stops. Finally, we take three CB lines in Beijing as examples for numerical experiment, the theoretical and numerical results show that (i) compared with the current situation, although the actual operating cost of optimized route increases slightly, it is covered by the reduction of travel cost of passengers and the transmission risk of COVID-19 has also dropped significantly; (ii) the improved Q-learning algorithm can solve the problem of data transmission lag effectively and reduce the social total travel cost obviously.

11.
J Med Chem ; 2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34797984

RESUMO

Antiviral therapy of influenza virus infections depends heavily on two viral neuraminidase (NA) inhibitors, oseltamivir (OSV) and zanamivir (ZNV). The efficacy of OSV is challenged by the development of viral resistance, while the clinical use of ZNV is limited by its poor pharmacokinetic profile and requirement for twice-daily intranasal administration. We have developed a novel NA inhibitor by conjugating ZNV to cholesterol. The ZNV-cholesterol conjugate showed markedly improved antiviral efficacy and plasma half-life compared with ZNV. Single-dose administration of the conjugate protected the mice from lethal challenges with wild-type or mutant H1N1 influenza viruses bearing an OSV-resistant H275Y-substitution. Mechanistic studies showed that the conjugate targeted the cell membrane and entered the host cells, thereby inhibiting the NA function and the assembly of progeny virions. The ZNV-cholesterol conjugate represents a potential new treatment for influenza infections with sustained effect. Cholesterol conjugation may be an effective strategy for improving the pharmacokinetics and efficacy of other small-molecule therapeutics.

12.
BMC Neurol ; 21(1): 440, 2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34753435

RESUMO

BACKGROUND: Patients with acute non-lacunar single subcortical infarct (SSI) associated with mild intracranial atherosclerosis (ICAS) have a relatively high incidence of early neurological deterioration (END), resulting in unfavorable functional outcomes. Whether the early administration of argatroban and aspirin or clopidogrel within 6-12 h after symptom onset is effective and safe in these patients is unknown. METHODS: A review of the stroke database of Weihai Municipal Hospital, Cheeloo College of Medicine, Shandong University and Qingdao Center Hospital, Qingdao University Medical College in China was undertaken from May 2017 to January 2020 to identify all patients with non-lacunar SSI caused by ICAS within 6-12 h of symptom onset based on MRI screening. Patients were divided into two groups, one comprising those who received argatroban and mono antiplatelet therapy with aspirin or clopidogrel on admission (argatroban group), and the other those who received dual antiplatelet therapy (DAPT) with aspirin and clopidogrel during hospitalization (DAPT group). The primary outcome was recovery by 90 days after stroke based on a modified Rankin scale (mRS) score (0 to 1). The secondary outcome was END incidence within 120 h of admission. Safety outcomes were intracranial hemorrhage (ICH) and major extracranial bleeding. The probability of clinical benefit (mRS score 0-1 at 90 days) was estimated using multivariable logistic regression analysis. RESULTS: A total of 304 acute non-lacunar SSI associated with mild ICAS patients were analyzed. At 90 days, 101 (74.2%) patients in the argatroban group and 80 (47.6%) in the DAPT group had an mRS score that improved from 0 to 1 (P < 0.001). The relative risk (95% credible interval) for an mRS score improving from 0 to 1 in the argatroban group was 1.50 (1.05-2.70). END occurred in 10 (7.3%) patients in the argatroban group compared with 37 (22.0%) in the DAPT group (P < 0.001). No patients experienced symptomatic hemorrhagic transformation. CONCLUSIONS: Early combined administration of argatroban and an antiplatelet agent (aspirin or clopidogrel) may be beneficial for patients with non-lacunar SSI associated with mild ICAS identified by MRI screening and may attenuate progressive neurological deficits. TRIAL REGISTRATION: Our study is a retrospectively registered trial.


Assuntos
Arteriosclerose Intracraniana , Inibidores da Agregação Plaquetária , Acidente Vascular Cerebral Lacunar , Arginina/análogos & derivados , Quimioterapia Combinada , Humanos , Arteriosclerose Intracraniana/diagnóstico por imagem , Arteriosclerose Intracraniana/tratamento farmacológico , Ácidos Pipecólicos/uso terapêutico , Inibidores da Agregação Plaquetária/uso terapêutico , Acidente Vascular Cerebral Lacunar/diagnóstico por imagem , Acidente Vascular Cerebral Lacunar/tratamento farmacológico , Sulfonamidas/uso terapêutico , Resultado do Tratamento
13.
Cell Rep ; 37(6): 109920, 2021 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-34731648

RESUMO

It is urgent to develop disease models to dissect mechanisms regulating severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Here, we derive airway organoids from human pluripotent stem cells (hPSC-AOs). The hPSC-AOs, particularly ciliated-like cells, are permissive to SARS-CoV-2 infection. Using this platform, we perform a high content screen and identify GW6471, which blocks SARS-CoV-2 infection. GW6471 can also block infection of the B.1.351 SARS-CoV-2 variant. RNA sequencing (RNA-seq) analysis suggests that GW6471 blocks SARS-CoV-2 infection at least in part by inhibiting hypoxia inducible factor 1 subunit alpha (HIF1α), which is further validated by chemical inhibitor and genetic perturbation targeting HIF1α. Metabolic profiling identifies decreased rates of glycolysis upon GW6471 treatment, consistent with transcriptome profiling. Finally, xanthohumol, 5-(tetradecyloxy)-2-furoic acid, and ND-646, three compounds that suppress fatty acid biosynthesis, also block SARS-CoV-2 infection. Together, a high content screen coupled with transcriptome and metabolic profiling reveals a key role of the HIF1α-glycolysis axis in mediating SARS-CoV-2 infection of human airway epithelium.

14.
Opt Lett ; 46(22): 5595-5598, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34780414

RESUMO

An ultra-compact in-core-parallel-written fiber Bragg grating (FBG) and Mach-Zehnder interferometer (MZI) for simultaneous measurement of strain and temperature is described. The FBG and MZI are written spatially parallel in the same section of fiber core using a femtosecond laser, forming an ultra-compact device, which is different from the previously developed axial cascade of different structures. Due to the weak coupling between the FBG and the MZI, their individual extinction ratios are traded off by optimizing their writing position and separation, and extinction ratios of 5.9 dB for the FBG and 10 dB for the MZI are achieved. Experimental results show that the FBG and MZI have different sensitivities for strain and temperature, allowing this device to measure strain and temperature simultaneously. In addition, since both the FBG and MZI are written in the fiber core, this ultra-compact device is proven to be impervious to ambient humidity, making it a promising candidate for accurate industrial strain and temperature measurements.

15.
Front Genet ; 12: 689748, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34737761

RESUMO

Piglet diarrhea is a swine disease responsible for serious economic impacts in the pig industry. Clostridium perfringens beta2 toxin (CPB2), which is a major toxin of C. perfringens type C, may cause intestinal diseases in many domestic animals. N6-methyladenosine (m6A) RNA methylation plays critical roles in many immune and inflammatory diseases in livestock and other animals. However, the role of m6A methylation in porcine intestinal epithelial (IPEC-J2) cells exposed to CPB2 has not been studied. To address this issue, we treated IPEC-J2 cells with CPB2 toxin and then quantified methylation-related enzyme expression by RT-qPCR and assessed the m6A methylation status of the samples by colorimetric N6-methyladenosine quantification. The results showed that the methylation enzymes changed to varying degrees while the m6A methylation level increased (p < 0.01). On this basis, we performed N6-methyladenosine sequencing (m6A-seq) and RNA sequencing (RNA-seq) to examine the detailed m6A modifications and gene expression of the IPEC-J2 cells following CPB2 toxin exposure. Our results indicated that 1,448 m6A modification sites, including 437 up-regulated and 1,011 down-regulated, differed significantly between CPB2 toxin exposed cells and non-exposed cells (p < 0.05). KEGG pathway analysis results showed that m6A peaks up-regulated genes (n = 394) were mainly enriched in cancer, Cushing syndrome and Wnt signaling pathways, while m6A peaks down-regulated genes (n = 920) were mainly associated with apoptosis, small cell lung cancer, and the herpes simplex virus 1 infection signaling pathway. Furthermore, gene expression (RNA-seq data) analysis identified 1,636 differentially expressed genes (DEGs), of which 1,094 were up-regulated and 542 were down-regulated in the toxin exposed group compared with the control group. In addition, the down-regulated genes were involved in the Hippo and Wnt signaling pathways. Interestingly, the combined results of m6A-seq and RNA-seq identified genes with up-regulated m6A peaks but with down-regulated expression, here referred to as "hyper-down" genes (n = 18), which were mainly enriched in the Wnt signaling pathway. Therefore, we speculate that the genes in the Wnt signaling pathway may be modified by m6A methylation in CPB2-induced IPEC-J2 cells. These findings provide new insights enabling further exploration of the mechanisms underlying piglet diarrhea caused by CPB2 toxin.

16.
Artigo em Inglês | MEDLINE | ID: mdl-34723473

RESUMO

Lithium (Li) metal has emerged as a promising electrode material for high-energy-density batteries. However, serious Li dendrite issues during cycling have plagued the safety and cyclability of the batteries, thus limiting the practical application of Li metal batteries. Herein, we prepare a novel metal-organic-framework-based (MOF-based) succinonitrile electrolyte, which enables homogeneous and fast Li-ion (Li+) transport for dendrite-free Li deposition. Given the appropriate aperture size of the MOF skeleton, the targeted electrolyte can allow only small-size Li+ to pass through its pores, which effectively guides uniform Li+ transport. Specially, Li ions are coordinated by the C═N of the MOF framework and the C≡N of succinonitrile, which could accelerate Li+ migration jointly. These characteristics afford an excellent quasi-solid-state electrolyte with a high ionic conductivity of 7.04 × 10-4 S cm-1 at room temperature and a superior Li+ transference number of 0.68. The Li/LiFePO4 battery with the MOF-based succinonitrile electrolyte exhibits dendrite-free Li deposition during the charge process, accompanied by a high capacity retention of 98.9% after 100 cycles at 0.1C.

17.
Cell Cycle ; : 1-18, 2021 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-34747340

RESUMO

This study explored the effects of miR-125-5p and interleukin-6 receptor (IL-6 R) on ulcerative colitis (UC) cell models and mouse models. The sera derived from UC patients and healthy subjects were collected for expression analysis. UC in vitro models and in vivo model were constructed and used. Expressions of miR-125-5p, IL-6 R, AK1/STAT3 and NF-κB pathways, and inflammatory factors, histopathology and apoptosis were determined by conducting a series of molecular experiments. The relationship between miR-125-5p and IL-6 R was analyzed by TargetScan7.2 and verified by dual-luciferase assay. The disease activity index (DAI) score, weight change, and colon length of the mice were recorded and analyzed. Decreased expression of miR-125-5p in the sera of UC patients was related to the increased expression of its target gene IL-6 R. In vitro, up-regulation of miR-125-5p decreased IL-6 R expression, contents of inflammatory factors in THP-1 cells and cell apoptosis of NCM460, and inhibited the activation of JAK1/STAT3 and NF-κB pathway. However, down-regulation of miR-125-5p produced the opposite effects to its up-regulation. IL-6 R overexpression partially reversed the effects of miR-125-5p up-regulation on UC cell models. In vivo, miR-125-5p overexpression significantly improved the severity of colitis, including DAI score, colon length, tissue damage, apoptosis, and inflammatory response, in the mice in the UC group. In addition, miR-125-5p up-regulation significantly reduced the expression of IL-6 R in the UC mice, and reduced the expression levels of JAK1, STAT3 and p65 phosphorylation. MiR-125-5p targeting IL-6 R regulates macrophage inflammatory response and intestinal epithelial cell apoptosis in ulcerative colitis through JAK1/STAT3 and NF-κB pathway.

18.
Chem Commun (Camb) ; 57(86): 11334-11337, 2021 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-34642730

RESUMO

An organocatalytic approach to installing various alcohols into the carbonyl of α,ß-unsaturated ketones mediated by VQM intermediates was achieved, followed by dearomatization to provide the stereo-defined cyclic ethers via a cascade process. Along with the transformations, this strategy affords efficient access to the underexplored chiral cyclic ether chemospace.

19.
Inflammation ; 2021 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-34599707

RESUMO

A new method for targeting lung infections is of great interest using biodegradable nanoparticles. In this study, bergenin-loaded BSA NPs were developed against lung injury. Briefly, bergenin-loaded bovine serum albumin nanoparticles (BG@BSA NPs) were synthesized and characterized. HPLC recorded the major peak of bergenin. UV-Vis spectra had an absorbance at 376 nm. XRD revealed the presence of crystalline particles. FTIR confirmed the occurrence of functionalized molecules in the synthesized NPs. The particles were highly stable with a net negative charge of - 24.2. The morphology of NPs was determined by SEM and TEM. The mean particle size was 124.26 nm. The production of NO by NR8383 cells was decreased by BG@BSA NPs. Also, in mice, lipopolysaccharide-mediated acute lung inflammation was induced. BG@BSA NPs reduced macrophages and neutrophils in BALF and remarkably enhanced wet weight-to-dry weight (W/D) ratios and myeloperoxidase (MPO) activity. Further, BG@BSA NPs inhibited the production of inflammatory cells as well as tumor necrosis factor. The histopathological studies revealed that the damage and neutrophil infiltration were greatly inhibited by BG@BSA NPs. This indicates that BG@BSA NPs may be used to treat lung infections. Therefore, this study has given new insight into producing an active drug for the treatment of lung-associated diseases in the future.

20.
Opt Express ; 29(17): 26353-26365, 2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34615072

RESUMO

Cross-sensitivity (crosstalk) to multiple parameters is a serious but common issue for most sensors and can significantly decrease the usefulness and detection accuracy of sensors. In this work, a high sensitivity temperature sensor based on a small air core (10 µm) hollow core fiber (SACHCF) structure is proposed. Co-excitation of both anti-resonant reflecting optical waveguide (ARROW) and Mach-Zehnder interferometer (MZI) guiding mechanisms in transmission are demonstrated. It is found that the strain sensitivity of the proposed SACHCF structure is decreased over one order of magnitude when a double phase condition (destructive condition of MZI and resonant condition of ARROW) is satisfied. In addition, due to its compact size and a symmetrical configuration, the SACHCF structure shows ultra-low sensitivity to curvature and twist. Experimentally, a high temperature sensitivity of 31.6 pm/°C, an ultra-low strain sensitivity of -0.01pm/µÎµ, a curvature sensitivity of 18.25 pm/m-1, and a twist sensitivity of -22.55 pm/(rad/m) were demonstrated. The corresponding temperature cross sensitivities to strain, curvature and twist are calculated to be -0.00032 °C/µÎµ, 0.58 °C/m-1 and 0.71 °C/(rad/m), respectively. The above cross sensitivities are one to two orders of magnitude lower than that of previously reported optical fiber temperature sensors. The proposed sensor shows a great potential to be used as a temperature sensor in practical applications where influence of multiple environmental parameters cannot be eliminated.

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