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1.
Biomed Pharmacother ; 137: 111367, 2021 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-33588265

RESUMO

BACKGROUND: Metabolic syndrome (MS) is a major global health concern comprising a cluster of co-occurring conditions that increase the risk of heart disease, stroke and type 2 diabetes. MS is usually diagnosed using a combination of physiochemical indexes (such as BMI, abdominal circumference and blood pressure) but largely ignores clinical symptoms when investigating prevention and treatment of the disease. Exploring predictors of MS using multiple diagnostic indicators may improve early diagnosis and treatment of MS. Traditional Chinese medicine (TCM) attaches importance to the etiology of disease symptoms and indications using four diagnostic methods, which have long been used to treat metabolic disease. Therefore, in this study, we aimed to develop predictive indicators for MS using both physiochemical indexes and TCM methods. METHODS: Clinical information (including both physiochemical and TCM indexes) was obtained from a cohort of 586 individuals across 4 hospitals in China, comprising 136 healthy controls and 450 MS cases. Using this cohort, we compared three classic machine learning methods: decision tree (DT), support vector machine (SVM) and random forest (RF) towards MS diagnosis using physiochemical and TCM indexes, with the best model selected by comparing the accuracy, specificity and sensitivity of the three models. In parallel, the best proportional partition of the training data to the test data was confirmed by observing the changes in evaluation indexes using each model. Next, three subsets containing different categories of variables (including both TCM and physicochemical indexes combined - termed the "fused indexes", only physicochemical indexes, and TCM indexes only) were compared and analyzed using the best performing model and optimum training to test data proportion. Next, the best subset was selected through comprehensive comparative analysis, and then the important prediction variables were selected according to their weight. RESULTS: When comparing the three models, we found that the RF model had the highest average accuracy (average 0.942, 95%CI [0.925, 0.958]) and sensitivity (average 0.993, 95%CI [0.990, 0.996]). Besides, when the training set accounted for 80% of the cohort data, the specificity got the best value and the accuracy and sensitivity were also very high in RF model. In view of the performance of the three different subsets, the prediction accuracy and sensitivity of models analyzing the fused indexes and only physicochemical indexes remained at a high level. Further, the mean value of specificity of the model using fused indexes was 0.916, which was significantly higher than the model with only physicochemical indexes (average 0.822) and the model with only TCM indexes (average 0.403). Based on the RF model and data allocation ratio (8:2), we further extracted the top 20 most significant variables from the fused indexes, which included 14 physicochemical indexes and 6 TCM indexes including wiry pulse, chest tightness, spontaneous perspiration, greasy tongue coating etc. CONCLUSION: Compared with SVM and DT models, the RF model showed the best performance, especially when the ratio of the training set to test set is 8:2. Compared with single predictive indexes, the model constructed by combining physiochemical indexes with TCM indexes (i.e. the fused indexes) exhibited better predictive ability. In addition to common physicochemical indexes, some TCM indexes, such as wiry pulse, chest tightness, spontaneous perspiration, greasy tongue coating, can also improve diagnosis of MS.

2.
J Photochem Photobiol B ; 216: 112147, 2021 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-33561689

RESUMO

Ultraviolet B (UVB) from the sunlight is a major environmental cause for human skin damages, inducing cell death, inflammation, senescence and even carcinogenesis. The natural flavonoid silibinin, clinically used as liver protectant, has protective effects against UVB-caused skin injury in vivo and in vitro. Silibinin is often classified as a phytoestrogen, because it modulates the activation of estrogen receptors (ERs). However, whether silibinin's estrogenic effect contributes to the skin protection against UVB injury remains to be elucidated. The issue was explored in this study by using the human foreskin dermal fibroblasts (HFF) and human non-malignant immortalized keratinocytes (HaCaT). In HFF, pre-treatment with silibinin rescued UVB-irradiated cells from apoptosis. Interestingly, silibinin increased the whole cellular and nuclear levels of ERα and ERß in UVB-irradiated cells. Activation of ERs by treatment with estradiol elevated the cell survival and reduced apoptosis in UVB-treated cells. ERα agonist increased cell survival, while its antagonist decreased it. ERß agonist also increased cell survival, but the antagonist had no effect on cell survival. Transfection of the cells with the small interfering RNAs (si-RNAs) to ERα or ERß diminished the protective effect of silibinin on UVB-irradiated cells. In UVB-treated HaCaT cells, both ERα and ERß were increased by silibinin treatment. Inhibition of activation and expression of ERα or ERß by specific antagonists and si-RNAs, respectively, reduced cell survival in UVB-treated HaCaT cells regardless of silibinin treatment. Taken together, it is summarized that silibinin up-regulates both ERα and ERß pathways in UVB-treated dermal HFF cells and epidermal HaCaT cells, leading to protection of skin from UVB-damage.

3.
Anal Methods ; 2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-33565542

RESUMO

Mercury is a highly toxic metal element, and the accumulation of mercury in the human body can cause great harm, including but not limited to brain damage, kidney damage and behavioral disorders. Therefore, an effective way to detect mercury ions in the environment is urgently needed. In this study, a novel fluorescent probe (CP-Hg) was synthesized with coumarin as the fluorophore and propanethiol as the recognition receptor. The probe was characterized with high sensitivity (detection limit is approximately 0.5 nM) and selectivity. Note that the probe can react with mercury ions with a distinct color change. In addition, it has been proved to have low toxicity and successfully applied to detect mercury in water samples, macrophages and zebrafish model.

4.
Artigo em Inglês | MEDLINE | ID: mdl-33590614

RESUMO

Three-dimensional (3D) organic-inorganic hybrid perovskites have demonstrated excellent capability in solar fuel production, while the two-dimensional (2D) counterparts are generally considered inferior candidates due to the high exciton binding energy and weak light absorption. Herein, contrary to our common understanding, we find that 2D perovskites can perform photocatalytic H2 production from HI splitting more efficiently than their 3D counterparts. We observed sharp difference between 2D perovskites crystals with organic phenylalkylammonium cations of different lengths and the 3D counterparts in their stabilization behavior in aqueous solution. Moreover, we show that the organic cations length of the 2D perovskites affects the nanostructures, optoelectronic properties, and the charge transfer process significantly, which determines the photocatalytic activity of the 2D perovskites. Among the 2D perovskites under investigation, phenylmethylammonium lead iodide with the shortest organic cations achieved the best solar-to-chemical conversion efficiency of ca. 1.57 %, which is the highest value ever reported for hybrid perovskites.

5.
Artigo em Inglês | MEDLINE | ID: mdl-33438300

RESUMO

Fabrication of 3d metal-based core@shell nanocatalysts with engineered Pt-surfaces provides an effective approach for improving the catalytic performance. The challenges in such preparation include shape control of the 3d metallic cores and thickness control of the Pt-based shells. Herein, we report a colloidal seed-mediated method to prepare octahedral CuNi@Pt-Cu core@shell nanocrystals using CuNi octahedral cores as the template. By precisely controlling the synthesis conditions including the deposition rate and diffusion rate of the shell-formation through tuning the capping ligand, reaction temperature, and heating rate, uniform Pt-based shells can be achieved with a thickness of <1 nm. The resultant carbon-supported CuNi@Pt-Cu core@shell nano-octahedra showed superior activity in electrochemical methanol oxidation reaction (MOR) compared with the commercial Pt/C catalysts and carbon-supported CuNi@Pt-Cu nano-polyhedron counterparts.

6.
Commun Biol ; 4(1): 53, 2021 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-33420329

RESUMO

The G protein-coupled receptor 109 A (GPR109A) is robustly expressed in osteoclastic precursor macrophages. Previous studies suggested that GPR109A mediates effects of diet-derived phenolic acids such as hippuric acid (HA) and 3-(3-hydroxyphenyl) propionic acid (3-3-PPA) on promoting bone formation. However, the role of GPR109A in metabolic bone homeostasis and osteoclast differentiation has not been investigated. Using densitometric, bone histologic and molecular signaling analytic methods, we uncovered that bone mass and strength were significantly higher in tibia and spine of standard rodent diet weaned 4-week-old and 6-month-old GPR109A gene deletion (GPR109A-/-) mice, compared to their wild type controls. Osteoclast numbers in bone and in ex vivo bone marrow cell cultures were significantly decreased in GPR109A-/- mice compared to wild type controls. In accordance with these data, CTX-1 in bone marrow plasma and gene expression of bone resorption markers (TNFα, TRAP, Cathepsin K) were significantly decreased in GPR109A-/- mice, while on the other hand, P1NP was increased in serum from both male and female GPR109A-/- mice compared to their respective controls. GPR109A deletion led to suppressed Wnt/ß-catenin signaling in osteoclast precursors to inhibit osteoclast differentiation and activity. Indeed, HA and 3-3-PPA substantially inhibited RANKL-induced GPR109A expression and Wnt/ß-catenin signaling in osteoclast precursors and osteoclast differentiation. Resultantly, HA significantly inhibited bone resorption and increased bone mass in wild type mice, but had no additional effects on bone in GPR109A-/- mice compared with their respective untreated control mice. These results suggest an important role for GPR109A during osteoclast differentiation and bone resorption mediating effects of HA and 3-3-PPA on inhibiting bone resorption during skeletal development.

7.
Clin Infect Dis ; 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-33515458

RESUMO

BACKGROUND: Mass vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is ongoing amidst widespread transmission during the Coronavirus Disease 2019 (COVID-19) pandemic. Disease phenotypes of SARS-CoV-2 exposure occurring around the time of vaccine administration have not been described. METHODS: Two-dose (14 days apart) vaccination regimen with a formalin-inactivated whole virion SARS-CoV-2 in golden Syrian hamster model was established. To investigate the disease phenotypes of a one-dose regimen given 3 days prior (D-3), 1 (D1) or 2 (D2) days after, or on the day (D0) of virus challenge, we monitored the serial clinical severity, tissue histopathology, virus burden, and antibody response of the vaccinated hamsters. RESULTS: The one-dose vaccinated hamsters had significantly lower clinical disease severity score, body weight loss, lung histology score, nucleocapsid protein expression in lung, infectious virus titres in the lung and nasal turbinate, inflammatory changes in intestines and a higher serum neutralizing antibody or IgG titre against the spike receptor-binding domain or nucleocapsid protein when compared to unvaccinated controls. These improvements were particularly noticeable in D-3, but also in D0, D1 and even D2 vaccinated hamsters to varying degrees. No increased eosinophilic infiltration was found in the nasal turbinate, lung, and intestine after virus challenge. Significantly higher serum titre of fluorescent foci microneutralization inhibition antibody was detected in D1 and D2 vaccinated hamsters at day 4 post-challenge compared to controls despite undetectable neutralizing antibody titre. CONCLUSIONS: Vaccination just before or soon after exposure to SARS-CoV-2 does not worsen disease phenotypes and may even ameliorate infection.

8.
Mol Immunol ; 131: 180-190, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33423764

RESUMO

Exposure to ultraviolet B (UVB) from sunlight causes DNA damage, serious cellular inflammation and aging, and even cell death in the skin, commonly known as sunburn, leading to cutaneous tissue disorders. DNA damage can be sensed as a danger-associated molecular pattern (DAMP) by the innate immune system. It has not been studied, however, whether cGAS-STING activation is involved in the apoptosis induced by UVB irradiation or by cisplatin treatment. Here we report the findings that within hours of DNA damages keratinocytes show an innate immune response, which involves the activation of cGAS-STING; a cytosolic DNA receptor, cGAS (cyclic guanosine monophosphate-adenosine monophosphate synthase), cyclic GMP-AMP (cGAMP) synthase, and DNA sensing adaptor, STING (protein stimulator of interferon genes). Either UVB irradiation or cisplatin treatment can cause DNA damages, releasing fragmented DNA from nucleus and/or mitochondria. Roles of cGAS-STING were examined in the HaCaT cells with DNA damages caused by UVB irradiation or cisplatin treatment. Silencing STING by siRNA rescued HaCaT cells from UVB or cisplatin-induced apoptosis. NF-κB, one of the major downstream components of STING pathway, which usually regulates the classical STING apoptotic pathway, was translocated to nucleus in the HaCaT cells irradiated with UVB. This translocation was attenuated by STING silencing. Treatment with BAY, an inhibitor of NF-κB pathway, blocked UVB-induced apoptosis. cGAS-STING-mediated production of IFNß was induced by nuclear translocation of interferon regulatory factor 3 (IRF3). UVB irradiation inceased the nuclear translocation of IRF3, accompanied by enhanced expression level of IFNß mRNA. The nuclear translocation of IRF3 and expression of IFNß mRNA were attenuated by STING silencing. Treatment with MRT67307, an inhibitor of TBK1-IRF3-IFNß pathway, blocked UVB-induced apoptosis. Therefore, we conclude that NF-κB pathway and IFNß pathway residing in the downstream of STING are resposible for apoptosis of UVB-irradiated or cisplatin-treated HaCaT cells.

9.
Chem Commun (Camb) ; 57(10): 1230-1233, 2021 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-33416810

RESUMO

This work discloses a Cu(ii)-Ni(ii) catalyzed tandem hydrocarboxylation of alkynes with polysilylformate formed from CO2 and polymethylhydrosiloxane that affords α,ß-unsaturated carboxylic acids with up to 93% yield. Mechanistic studies indicate that polysilylformate functions as a source of CO and polysilanol. Besides, a catalytic amount of water is found to be critical to the reaction, which hydrolyzes polysilylformate to formic acid that induces the formation of Ni-H active species, thereby initiating the catalytic cycle.

10.
J Dairy Sci ; 2021 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-33455776

RESUMO

Chymosin is a predominant enzyme in rennet and is used in cheese production because of its excellent milk-clotting activity. Herein, we proposed a facile and label-free electrochemical method for determining chymosin activity based on a peptide-based enzyme substrate. The synthesized substrate peptide for chymosin was assembled onto the surface of the Au-deposited grassy carbon electrode. The current was proportional to chymosin activity, and thus chymosin activity could be determined. The detection ranges of chymosin activity were 2.5 to 25 U mL-1. The detection limit of chymosin activity was 0.8 U mL-1. The sensing platform was used to quantify chymosin activity in commercial rennet with high selectivity, excellent stability, and satisfactory reproducibility. We developed a facile, fast, and effective electrochemical assay for detecting chymosin activity, which has potential applications in cheesemaking.

11.
J Cell Physiol ; 2021 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-33452687

RESUMO

Osteoarthritis (OA) is the most common joint disease. The surface of joint cartilage is a defensive and first affected structure of articular cartilage (AC) during the pathogenesis of OA. Alk5 signaling is critical for maintaining AC homeostasis, however, the role and underlying mechanism for the involvement of Alk5 signaling in the phenotypes of articular cartilage stem cells (ACSCs) at the surface of AC is still unclear. The role of Alk5 in OA development was explored using an ACSCs-specific Alk5-deficient (cKO) mouse model. Alterations in cartilage structure were evaluated histologically. Senescence was detected by SA-ß-gal, while reactive oxygen species (ROS), MitoTracker, and LysoTracker staining were used to detect changes related to senescence. In addition, mice were injected intra-articularly with ganciclovir to limit the detrimental roles of senescent cells (SnCs). Alk5 cKO mice showed a decreased number of the slow-cell cycle cells and less lubricant secretion at the surface accompanied with drastically accelerated cartilage degeneration under ageing and surgically induced OA conditions. Further studies showed that Alk5 deficient ACSCs exhibited senescence-like manifestations including decreased proliferation and differentiation, more SA-ß-gal-positive cells and ROS production, as well as significantly swollen mitochondria and lysosome breakdown. We further found that local limitation of the detrimental roles of SnCs can attenuate the development of posttraumatic OA. Taken together, our findings suggest that Alk5 signaling acts as an important regulator of the SnCs in the superficial layer during AC maintenance and OA initiation.

12.
Plant Sci ; 302: 110728, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33288029

RESUMO

Rice is one of the most important food crops in the world. Breeding high-yield, multi-resistant and high-quality varieties has always been the goal of rice breeding. Rice tiller, panicle architecture and grain size are the constituent factors of yield, which are regulated by both genetic and environmental factors, including miRNAs, transcription factors, and downstream target genes. Previous studies have shown that SPL (SQUAMOSA PROMOTER BINDING-LIKE) transcription factors can control rice tiller, panicle architecture and grain size, which were regulated by miR156, miR529 and miR535. In this study, we obtained miR529a target mimicry (miR529a-MIMIC) transgenic plants to investigate plant phenotypes, physiological and molecular characteristics together with miR529a overexpression (miR529a-OE) and wild type (WT) to explore the function of miR529a and its SPL target genes in rice. We found that OsSPL2, OsSPL17 and OsSPL18 at seedling stage were regulated by miR529a, but there had complicated mechanism to control plant height. OsSPL2, OsSPL16, OsSPL17 and SPL18 at tillering stage were regulated by miR529a to control plant height and tiller number. And panicle architecture and grain size were controlled by miR529a through altering the expression of all five target genes OsSPL2, OsSPL7, OsSPL14, OsSPL16, OsSPL17 and OsSPL18. Our study suggested that miR529a might control rice growth and development by regulating different SPL target genes at different stages, which could provide a new method to improve rice yield by regulating miR529a and its SPL target genes.

14.
Opt Lett ; 45(24): 6687-6690, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33325871

RESUMO

We extend rainbow refractometry to quantify the oscillations of a droplet in its fundamental mode. The oscillation parameters (frequency and amplitude damping), extracted using the time-resolved rainbow angular shift, are utilized to measure surface tension and viscosity of the liquid. Proof-of-concept experiments on an oscillating droplet stream produced by a monodisperse droplet generator are conducted. Results show that the relative measurement errors of surface tension and viscosity are 1.5% and 8.4% for water and 5.3% and 2.5% for ethanol. This approach provides an alternative mean for characterizing liquid surface properties, e.g., dynamic surface tension and viscosity, especially for liquids with a low Ohnesorge number.

15.
Artigo em Inglês | MEDLINE | ID: mdl-33340205

RESUMO

Ferrihydrite (Fh) has been demonstrated acting as a hole-storage layer (HSL) in photoelectrocatalysis system. However, the intrinsic structure responsible for the hole storage function for Fh remains unclear. Herein, by dehydrating the Fh via a careful calcination, the essential relation between the HSL function and the structure evolution of Fh material is unraveled. The irreversible and gradual loss of crystal water molecules in Fh leads to the weakening of the HSL function, accompanied with the arrangement of inner structure units. A structure evolution of the dehydration process is proposed and the primary active structure of Fh for HSL is identified as the [FeO6 ] polyhedral units bonding with two or three molecules of crystal water. With the successive loss of chemical crystal water, the coordination symmetry of [FeO6 ] hydration units undergoes mutation and a more ordered structure is formed, causing the difficulty for accepting photogenerated holes as a consequence.

16.
J Sci Food Agric ; 2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-33349937

RESUMO

BACKGROUND: Cassava is rich in nutrition and has high edible value, but the development of the cassava industry is limited by the traditional low added value processing and utilization mode. In this study, cassava tuber was used as beer adjunct to develop a complete set of fermentation technology for manufacturing cassava beer. RESULTS: The activities of transaminase, phenylpyruvate decarboxylase and dehydrogenase in 2-phenylethanol Ehrlich biosynthesis pathway of Saccharomyces cerevisiae were higher in cassava beer than that of malt beer. Aminotransferase ARO9 gene and phenylpyruvate decarboxylase ARO10 gene were up-regulated in the late stage of fermentation, which indicated that they were the main regulated genes of 2-phenylethanol Ehrlich pathway with phenylalanine as substrate in cassava beer preparation. CONCLUSIONS: Compared with traditional wheat beer, cassava beer was similar in the content of nutrition elements, diacetyl, total acid, alcohol and carbon dioxide, but has the characteristics of fresh fragrance and better taste. The hydrocyanic acid contained in cassava root tubes was catabolized during fermentation and compliant with the safety standard of beverage. Further study found that the content of 2-phenylethanol in cassava beer increased significantly, which gave cassava beer a unique elegant and delicate rose flavor.

17.
Zhonghua Nan Ke Xue ; 26(2): 134-138, 2020 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-33346416

RESUMO

Objective: To investigate the efficiency, safety and clinical application value of scrotoscopy in the diagnosis and treatment of testicular and epididymal diseases. METHODS: A total of 39 patients with testicular or epididymal diseases underwent scrotoscopic surgery in our hospital from February 2015 to February 2018. We retrospectively analyzed the clinical data, results of surgery, and postoperative scrotal pain scores, complications and recurrence. RESULTS: Scrotoscopic surgery was successfully performed in all the 39 cases, without such severe complications as testis rupture and scrotal hematoma. Thirteen cases of epididymal tumor were treated by total excision of the tumors by laser ablation; 10 of the 12 patients complaining of chronic testicular pain were diagnosed with incomplete torsion of testicular or epididymal appendages and treated by holmium laser ablation; of the 11 cases of suspected testicular torsion, 8 were confirmed as testicular torsion and the other 3 as acute epididymitis; and 3 cases of scrotal trauma-induced old hematoma underwent surgical removal under the scrotoscope. No infection of scrotal incision occurred postoperatively. The visual analog pain scores of the patients averaged 3.4 ± 1.2 (2-5) and their hospital stay 3.2 ± 0.8 (3-6) days. Scrotal ultrasonography at 1 month after surgery revealed no abnormality in the testis, epididymis or spermatic cord. CONCLUSIONS: Scrotoscopy is safe and effective for the diagnosis and treatment of testicular and epididymal diseases and deserves a wide clinical application.


Assuntos
Epididimite/diagnóstico por imagem , Escroto/diagnóstico por imagem , Torção do Cordão Espermático/diagnóstico por imagem , Doenças Testiculares/diagnóstico por imagem , Humanos , Masculino , Estudos Retrospectivos , Escroto/cirurgia , Torção do Cordão Espermático/cirurgia , Doenças Testiculares/cirurgia
18.
Therap Adv Gastroenterol ; 13: 1756284820968423, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33193813

RESUMO

Background: We evaluated the safety and efficacy of fecal microbiota transplantation (FMT) for chronic functional constipation (CFC) ineffectively treated by conventional constipation medication. Methods: Thirty-four patients with CFC underwent FMT treatment (three rounds, via gastroscopy). Clinical scales, including the Wexner constipation score as the main index of efficiency, were completed at baseline; after each treatment, and at 2 and 3 months of follow up. Secondary evaluation indices included the self-assessment of constipation symptoms, patient assessment constipation quality-of-life questionnaire, Bristol stool form scale, and Zung's self-rating depression and anxiety scales. Gastrointestinal motility, motilin, gastrin, nitric oxide (NO), and 5-hydroxytryptamine (5-HT) were assessed before and after treatment. Intestinal flora changes were assessed by 16S ribosomal ribonucleic acid (rRNA) sequencing. Results: There were no serious adverse reactions. The clinical cure rate was 73.5% (25/34), clinical remission rate was 14.7% (5/34), and the inefficiency rate was 11.8% (4/34). Clinical scale data indicated that the FMT treatment was effective. Furthermore, FMT treatment promoted intestinal peristalsis, increased gastrointestinal motility, and increased serum NO and 5-HT levels. The 16S rRNA sequencing data indicated that high abundances of Bacteroides, Klebsiella, Megamonas, Erysipelotrichaceae and Epulopiscium may be the cause of constipation, and high abundances of Prevotella, Acidaminococcus and Butyricimonas may be the main factors in curing constipation. Conclusion: Treatment with FMT regulates the intestinal microflora and changes the abundance of CFC-associated bacterial flora to improve constipation.

19.
Front Chem ; 8: 794, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33195025

RESUMO

Biomass is a potential non-food, carbon-neutral, and abundant resource, which can be used as an alternative to fossil fuels during the sustainable preparation of various platform chemicals. Alkyl levulinates (ALs) have found widespread application as flavorings, plasticizing agents, and fuel additives, as well as synthetic precursors to various building blocks. Several processes have been investigated to transform biomass and its derivatives into ALs, which mainly include: (i) direct esterification of levulinic acid (LA) with alkyl alcohols and (ii) alcoholysis reactions of renewable biomass feedstocks and their derivatives, including furfuryl alcohol (FAL), chloromethyl furfural (CMF), and saccharides. This review focuses on illustrating the effects of the biomass pretreatment step, catalyst texture, possible mechanisms, acidities, and intermediates on the synthesis of ALs from sustainable resources covering a wide range of intermediates, including diethyl ether (DEE), 4,5,5-triethoxypentan-2-one (TEP), ethoxymethylfuran (EMF), ethyl-D-fructofuranoside (EDFF), and ethyl-D-glucopyranoside (EDGP).

20.
bioRxiv ; 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-33200127

RESUMO

Studies on human monocytes historically focused on characterization of bulk responses, whereas functional heterogeneity is largely unknown. Here, we identified an inducible population of CD127-expressing human monocytes under inflammatory conditions and named the subset M127. M127 is nearly absent in healthy individuals yet abundantly present in patients with infectious and inflammatory conditions such as COVID-19 and rheumatoid arthritis. Multiple genomic and functional approaches revealed unique gene signatures of M127 and unified anti-inflammatory properties imposed by the CD127-STAT5 axis. M127 expansion correlated with mild COVID-19 disease outcomes. Thereby, we phenotypically and molecularly characterized a human monocyte subset marked by CD127 that retained anti-inflammatory properties within the pro-inflammatory environments, uncovering remarkable functional diversity among monocytes and signifying M127 as a potential therapeutic target for human inflammatory disorders.

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