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1.
Mol Neurobiol ; 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38528305

RESUMO

Alzheimer's disease (AD) is a common age-associated progressive neurodegenerative disorder that is implicated in the aberrant regulation of numerous circular RNAs (circRNAs). Here, we reported that circ-Bptf, a conserved circRNA derived from the Bptf gene, showed an age-dependent decrease in the hippocampus of APP/PS1 mice. Overexpression of circ-Bptf significantly reversed dendritic spine loss and learning and memory impairment in APP/PS1 mice. Moreover, we found that circ-Bptf was predominantly localized to the cytoplasm and upregulated p62 expression by binding to miR-138-5p. Furthermore, the miR-138-5p mimics reversed the decreased expression of p62 induced by the silencing of circ-Bptf. Together, our findings suggested that circ-Bptf ameliorated learning and memory impairments via the miR-138-5p/p62 axis in APP/PS1 mice. It may act as a potential player in AD pathogenesis and therapy.

2.
Ann Med ; 55(2): 2290213, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38061697

RESUMO

PURPOSE: This study examined the protective effects and mechanism of Lycium barbarum polysaccharides (LBP) in the context of intestinal barrier function and intestinal microbiota in mice with dextran sulfate sodium (DSS)-induced chronic ulcerative colitis (UC). METHODS: C57BL/6J male mice were assigned to a standard normal diet without DSS (control group), a normal diet with DSS (DSS group, 2% DSS given discontinuously for 3 weeks) or a normal diet supplemented with LBP (1% dry feed weight, LBP group, 2% DSS given discontinuously for 3 weeks) for a total of 8 weeks, at which point colonic tissues and caecal contents were collected. RESULTS: LBP exerted a significant effect against colitis by increasing body weight, colon length, DAI and histopathological scores. LBP inhibited proinflammatory cytokines (IL-1ß, IL-6, iNOS and TNF-α) expression, improved anti-inflammatory cytokine (IL-10) expression, promoted the expression of tight junction proteins (Occludin and ZO-1) via nuclear factor erythroid 2-related factor 2 (Nrf2) activation and decreased Claudin-2 expression to maintain the intestinal mucosal barrier. In addition, the abundances of some probiotics (Ruminococcaceae, Lactobacillus, Butyricicoccus, and Akkermansia) were decreased with DSS treatment but increased obviously with LBP treatment. And LBP reduced the abundance of conditional pathogens associated with UC (Mucispirillum and Sutterella). Furthermore, LBP improved the production of short-chain fatty acids (SCFAs), including acetic acid, propionic acid, butyric acid and isobutyric acid. CONCLUSION: LBP can alleviate DSS-induced UC by regulating inflammatory cytokines and tight junction proteins. Moreover, LBP promotes probiotics, suppresses conditional pathogens and increases SCFAs production, showing a strong prebiotic effect.


Assuntos
Colite Ulcerativa , Microbioma Gastrointestinal , Humanos , Masculino , Animais , Camundongos , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/tratamento farmacológico , Função da Barreira Intestinal , Sulfato de Dextrana/efeitos adversos , Camundongos Endogâmicos C57BL , Citocinas , Proteínas de Junções Íntimas/metabolismo , Peso Corporal , Modelos Animais de Doenças
3.
Zhongguo Zhong Yao Za Zhi ; 48(16): 4438-4445, 2023 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-37802870

RESUMO

This study aimed to investigate the effect and mechanism of Zuogui Jiangtang Qinggan Formula(ZGJTQG) on the glucolipid metabolism of type 2 diabetes mellitus(T2DM) complicated with non-alcoholic fatty liver disease(NAFLD). NAFLD was induced by a high-fat diet(HFD) in MKR mice(T2DM mice), and a model of T2DM combined with NAFLD was established. Forty mice were randomly divided into a model group, a metformin group(0.067 g·kg~(-1)), and high-and low-dose ZGJTQG groups(29.64 and 14.82 g·kg~(-1)), with 10 mice in each group. Ten FVB mice of the same age were assigned to the normal group. Serum and liver tissue specimens were collected from mice except for those in the normal and model groups after four weeks of drug administration by gavage, and fasting blood glucose(FBG) and fasting insulin(FINS) levels were measured. The levels of total cholesterol(TC), triglyceride(TG), and low-density lipoprotein(LDL) were detected by the single reagent GPO-PAP method. Very low-density lipoprotein(VLDL) was detected by enzyme-linked immunosorbent assay(ELISA). Alanine aminotransferase(ALT) and aspartate ami-notransferase(AST) were determined by the Reitman-Frankel assay. The pathological changes in the liver were observed by hematoxylin-eosin(HE) staining and oil red O staining. Real-time fluorescence-based quantitative polymerase chain reaction(real-time PCR) and Western blot were adopted to detect the mRNA and protein expression of forkhead transcription factor O1(FoxO1), microsomal triglyceride transfer protein(MTP), and apolipoprotein B(APOB) in the liver. The results showed that high-dose ZGJTQG could signi-ficantly reduce the FBG and FINS levels(P<0.05, P<0.01), improve glucose tolerance and insulin resistance(P<0.05, P<0.01), alleviate the liver damage caused by HFD which was reflected in improving liver steatosis, and reduce the serum levels of TC, TG, LDL, VLDL, ALT, and AST(P<0.05, P<0.01) in T2DM mice combined with NAFLD. The findings also revealed that the mRNA and protein expression of FoxO1, MTP, and APOB in the liver was significantly down-regulated after the intervention of high-dose ZGJTQG(P<0.05, P<0.01). The above study showed that ZGJTQG could effectively improve glucolipid metabolism in T2DM combined with NAFLD, and the mechanism was closely related to the regulation of the FoxO1/MTP/APOB signaling pathway.


Assuntos
Diabetes Mellitus Tipo 2 , Hepatopatia Gordurosa não Alcoólica , Camundongos , Animais , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Fígado , Lipoproteínas LDL/metabolismo , Transdução de Sinais , Dieta Hiperlipídica/efeitos adversos , RNA Mensageiro/metabolismo
4.
Acta Pharmacol Sin ; 44(12): 2347-2357, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37532784

RESUMO

SARS-CoV-2 infection causes injuries of not only the lungs but also the heart and endothelial cells in vasculature of multiple organs, and induces systemic inflammation and immune over-reactions, which makes COVID-19 a disease phenome that simultaneously affects multiple systems. Cardiovascular diseases (CVD) are intrinsic risk and causative factors for severe COVID-19 comorbidities and death. The wide-spread infection and reinfection of SARS-CoV-2 variants and the long-COVID may become a new common threat to human health and propose unprecedented impact on the risk factors, pathophysiology, and pharmacology of many diseases including CVD for a long time. COVID-19 has highlighted the urgent demand for precision medicine which needs new knowledge network to innovate disease taxonomy for more precise diagnosis, therapy, and prevention of disease. A deeper understanding of CVD in the setting of COVID-19 phenome requires a paradigm shift from the current phenotypic study that focuses on the virus or individual symptoms to phenomics of COVID-19 that addresses the inter-connectedness of clinical phenotypes, i.e., clinical phenome. Here, we summarize the CVD manifestations in the full clinical spectrum of COVID-19, and the phenome-wide association study of CVD interrelated to COVID-19. We discuss the underlying biology for CVD in the COVID-19 phenome and the concept of precision medicine with new phenomic taxonomy that addresses the overall pathophysiological responses of the body to the SARS-CoV-2 infection. We also briefly discuss the unique taxonomy of disease as Zheng-hou patterns in traditional Chinese medicine, and their potential implications in precision medicine of CVD in the post-COVID-19 era.


Assuntos
COVID-19 , Doenças Cardiovasculares , Humanos , Doenças Cardiovasculares/genética , Fenômica , Medicina de Precisão , SARS-CoV-2/genética , Síndrome de COVID-19 Pós-Aguda , Células Endoteliais
5.
Orthop Surg ; 15(9): 2213-2224, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37435789

RESUMO

Knee osteoarthritis (KOA) is a chronic joint bone disease characterized by inflammatory destruction and hyperplasia of bone. Its main clinical symptoms are joint mobility difficulties and pain, severe cases can lead to limb paralysis, which poses major pressure to the quality of life and mental health of patients, but also brings serious economic burden to society. The occurrence and development of KOA is influenced by many factors, including systemic factors and local factors. The joint biomechanical changes caused by aging, trauma and obesity, abnormal bone metabolism caused by metabolic syndrome, the effects of cytokines and related enzymes, genetic and biochemical abnormalities caused by plasma adiponectin, etc. all directly or indirectly lead to the occurrence of KOA. However, there is little literature that systematically and comprehensively integrates macro- and microscopic KOA pathogenesis. Therefore, it is necessary to comprehensively and systematically summarize the pathogenesis of KOA in order to provide a better theoretical basis for clinical treatment.


Assuntos
Osteoartrite do Joelho , Humanos , Osteoartrite do Joelho/tratamento farmacológico , Qualidade de Vida , Osso e Ossos , Dor , Articulação do Joelho
6.
Plant Mol Biol ; 112(6): 341-356, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37523053

RESUMO

Cuticular wax, cutin and suberin polyesters covering the surface of some fleshy fruit are tightly associated with skin color and appearance. ß-Ketoacyl-CoA synthase (KCS) is a rate-limiting enzyme participating in the synthesis of very-long-chain fatty acids (VLCFAs), the essential precursors of cuticular waxes and aliphatic monomers of suberin. However, information on the KCS gene family in pear genome and the specific members involved in pear fruit skin formation remain unclear. In the present study, we performed an investigation of the composition and amount of cuticular waxes, cutin and aliphatic suberin in skins of four sand pear varieties with distinct colors (russet, semi-russet, and green) and demonstrated that the metabolic shifts of cuticular waxes and suberin leading to the significant differences of sand pear skin color. A genome-wide identification of KCS genes from the pear genome was conducted and 35 KCS coding genes were characterized and analyzed. Expression profile analysis revealed that the KCS genes had diverse expression patterns among different pear skins and the transcript abundance of PbrKCS15, PbrKCS19, PbrKCS24, and PbrKCS28 were consistent with the accumulation of cuticular waxes and suberin in fruit skin respectively. Subcellular localization analysis demonstrated that PbrKCS15, PbrKCS19, PbrKCS24 and PbrKCS28 located on the endoplasmic reticulum (ER). Further, transient over-expression of PbrKCS15, PbrKCS19, and PbrKCS24 in pear fruit skins significantly increased cuticular wax accumulation, whereas PbrKCS28 notably induced suberin deposition. In conclusion, pear fruit skin color and appearance are controlled in a coordinated way by the deposition of the cuticular waxes and suberin. PbrKCS15, PbrKCS19, and PbrKCS24 are involved in cuticular wax biosynthesis, and PbrKCS28 is involved in suberin biosynthesis, which play essential roles in pear fruit skin formation. Moreover, this work provides a foundation for further understanding the functions of KCS genes in pear.


Assuntos
Pyrus , Pyrus/genética , Pyrus/metabolismo , Frutas/genética , Frutas/metabolismo , Ceras/metabolismo , Regulação da Expressão Gênica de Plantas
7.
Planta ; 257(4): 69, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36854938

RESUMO

MAIN CONCLUSION: PpyMYB144 directly activates the promoter of PpyCYP86B1, promotes the synthesis of α, ω-diacids, and involves in pear fruit skin russeting. Russeting is an economically important surface disorder in pear (Pyrus pyrifolia) fruit. Previous research has demonstrated that suberin is the pivotal chemical component contributing to pear fruit skin russeting, and fruit bagging treatment effectively reduces the amount of suberin of fruits, and thereby reduces the russeting phenotype. However, the mechanisms of pear fruit skin russeting remain largely unclear, particularly the transcriptional regulation. Here, we dissected suberin concentration and composition of pear fruits along fruit development and confirmed that α, ω-diacids are the predominant constituents in russeted pear fruit skins. Two cytochrome P450 monooxygenase (CYP) family genes (PpyCYP86A1 and PpyCYP86B1) and nine MYB genes were isolated from pear fruit. Expressions of PpyCYP86A1, PpyCYP86B1, and five MYB genes (PpyMYB34, PpyMYB138, PpyMYB138-like, PpyMYB139, and PpyMYB144) were up-regulated during fruit russeting and showed significant correlations with the changes of α, ω-diacids. In addition, dual-luciferase assays indicated that PpyMYB144 could trans-activate the promoter of PpyCYP86B1, and the activation was abolished by motif mutagenesis of AC element on the PpyCYP86B1 promoter. Further, Agrobacterium-mediated transient expression of PpyCYP86B1 and PpyMYB144 in pear fruits induced the deposition of aliphatic suberin. Thus, PpyMYB144 is a novel direct activator of PpyCYP86B1 and contributes to pear fruit skin russeting.


Assuntos
Pyrus , Pyrus/genética , Frutas/genética , Metabolismo Secundário , Sistema Enzimático do Citocromo P-450/genética , Agrobacterium
8.
Curr Neuropharmacol ; 21(9): 1964-1979, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36797614

RESUMO

Exosomes, as nanoscale biological vesicles, have been shown to have great potential for biomedical applications. However, the low yield of exosomes limits their application. In this review, we focus on methods to increase exosome yield. Two main strategies are used to increase exosome production, one is based on genetic manipulation of the exosome biogenesis and release pathway, and the other is by pretreating parent cells, changing the culture method or adding different components to the medium. By applying these strategies, exosomes can be produced on a large scale to facilitate their practical application in the clinic.


Assuntos
Exossomos , Humanos , Exossomos/metabolismo
9.
World J Gastroenterol ; 28(33): 4846-4860, 2022 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-36156930

RESUMO

BACKGROUND: The frequency of acute hypertriglyceridemic pancreatitis (AHTGP) is increasing worldwide. AHTGP may be associated with a more severe clinical course and greater mortality than pancreatitis caused by other causes. Early identification of patients with severe inclination is essential for clinical decision-making and improving prognosis. Therefore, we first developed and validated a risk prediction score for the severity of AHTGP in Chinese patients. AIM: To develop and validate a risk prediction score for the severity of AHTGP in Chinese patients. METHODS: We performed a retrospective study including 243 patients with AHTGP. Patients were randomly divided into a development cohort (n = 170) and a validation cohort (n = 73). Least absolute shrinkage and selection operator and logistic regression were used to screen 42 potential predictive variables to construct a risk score for the severity of AHTGP. We evaluated the performance of the nomogram and compared it with existing scoring systems. Last, we used the best cutoff value (88.16) for severe acute pancreatitis (SAP) to determine the risk stratification classification. RESULTS: Age, the reduction in apolipoprotein A1 and the presence of pleural effusion were independent risk factors for SAP and were used to construct the nomogram (risk prediction score referred to as AAP). The concordance index of the nomogram in the development and validation groups was 0.930 and 0.928, respectively. Calibration plots demonstrate excellent agreement between the predicted and actual probabilities in SAP patients. The area under the curve of the nomogram (0.929) was better than those of the Bedside Index of Severity in AP (BISAP), Ranson, Acute Physiology and Chronic Health Evaluation (APACHE II), modified computed tomography severity index (MCTSI), and early achievable severity index scores (0.852, 0.825, 0.807, 0.831 and 0.807, respectively). In comparison with these scores, the integrated discrimination improvement and decision curve analysis showed improved accuracy in predicting SAP and better net benefits for clinical decisions. Receiver operating characteristic curve analysis was used to determine risk stratification classification for AHTGP by dividing patients into high-risk and low-risk groups according to the best cutoff value (88.16). The high-risk group (> 88.16) was closely related to the appearance of local and systemic complications, Ranson score ≥ 3, BISAP score ≥ 3, MCTSI score ≥ 4, APACHE II score ≥ 8, C-reactive protein level ≥ 190, and length of hospital stay. CONCLUSION: The nomogram could help identify AHTGP patients who are likely to develop SAP at an early stage, which is of great value in guiding clinical decisions.


Assuntos
Pancreatite , Doença Aguda , Apolipoproteína A-I , Proteína C-Reativa/metabolismo , China/epidemiologia , Humanos , Pancreatite/complicações , Pancreatite/diagnóstico , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença
10.
Chemosphere ; 291(Pt 1): 132705, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34710448

RESUMO

Atmospheric reaction mechanism and dynamics of phenol with nitrogen dioxide dimer were explored by the density functional theory and high-level quantum chemistry combined with statistical kinetic calculations within 220-800 K. The nitric acid and phenyl nitrite, the typical aerosol precursors, are the preponderant products because of the low formation free energy barrier (∼8.7 kcal/mol) and fast rate constants (∼10-15 cm3 molecule-1 s-1 at 298 K). Phenyl nitrate is the minor product and it would be also formed from the transformation of phenyl nitrite in NO2-rich environment. More importantly, kinetic effects and catalytic mechanism of a series of metal-free catalysts (H2O, NH3, CH3NH2, CH3NHCH3, HCOOH, and CH3COOH) on the title reaction were investigated at the same level. The results indicate that CH3NH2 and CH3NHCH3 can not only catalyze the title reaction by lowering the free energy barrier (about 1.4-6.5 kcal/mol) but also facilitate the production of organic ammonium nitrate via acting as a donor-acceptor of hydrogen. Conversely, the other species are non-catalytic upon the title reaction. The stabilization energies and donor-acceptor interactions in alkali-catalyzed product complexes were explored, which can provide new insights to the properties of aerosol precursors. Moreover, the lifetime of phenol determined by nitrogen dioxide dimer in the presence of dimethylamine may compete with that of determined by OH radicals, indicating that nitrogen dioxide dimer is responsible for the elimination of phenol in the polluted atmosphere. This work could help us thoroughly understand the removal of nitrogen oxides and phenol as well as new aerosol precursor aggregation in vehicle exhaust.


Assuntos
Dióxido de Nitrogênio , Fenol , Aerossóis , Catálise , Nitratos , Fenóis
11.
Front Pharmacol ; 12: 704112, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34483906

RESUMO

Metformin is the first-line anti-diabetic drug for type 2 diabetes. It has been found to significantly reduce liver aminotransferase in nonalcoholic fatty liver disease (NAFLD). However, whether metformin improves NAFLD progression remains controversial. Sirtuin 1 (SIRT1), an NAD+-dependent deacetylase, plays a vital role in hepatic steatosis and inflammation. Here, we investigated the effect of metformin on steatohepatitis and the role of SIRT1 in diet-induced obese (DIO) mice. The results showed that metformin significantly reduced body weight and fat mass of DIO mice. In addition, metformin also alleviated adiposity and hepatic steatosis, and greatly upregulated uncoupling protein 1 (UCP1) expression in adipose tissues of DIO mice. Unexpectedly, the effects of metformin on reducing body weight and alleviating hepatic steatosis were not impaired in Sirt1 heterozygous knockout (Sirt1 +/- ) mice. However, SIRT1-deficiency remarkably impaired the effects of metformin on lowering serum transaminases levels, downregulating the mRNA expression of proinflammatory factors, and increasing the protein level of hepatic Cholesterol 25-Hydroxylase (CH25H), a cholesterol hydroxylase in cholesterol catabolism. In summary, we demonstrated that metformin alleviates steatohepatitis in a SIRT1-dependent manner, and modulation of M1 polarization and cholesterol metabolism may be the underlying mechanism.

12.
Case Rep Infect Dis ; 2021: 5212401, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34336316

RESUMO

Fusobacterium nucleatum is an anaerobic oral commensal organism that is often associated with inflammatory bowel disease, adverse pregnancy outcomes, respiratory tract infections, and Lemierre's syndrome. Rheumatoid arthritis is often associated with pleuropulmonary manifestations including noninfectious pleural effusions and interstitial lung disease. We present a case of a 47-year-old man with progressive rheumatoid arthritis on immunosuppressive therapy who was found to have a left-sided pleural effusion, thought secondary to possible pneumonia, and was treated with levofloxacin and methylprednisolone. He presented a month later and was found to have a large left-sided thick-walled fluid collection found to be an empyema. A chest tube was placed, and fluid culture grew Fusobacterium nucleatum. The patient was successfully treated with intrapleural fibrinolytic therapy and amoxicillin-clavulanic acid.

14.
Food Chem ; 365: 130508, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34247046

RESUMO

Efforts to obtain organic trace elements have been made, including yeast enrichment and transformation, but the application of yeast for this purpose is restricted by poor tolerance and low enrichment. Siderophores play an important role in iron transport. Thus, the role of siderophores in iron transport under high-iron conditions and the application of siderophores in the enrichment of elements was explored. The results showed that some siderophores from iron-tolerant strains promoted yeast growth and increased its intracellular iron content. Among them, siderophore TZT-12 (from LK1110) was the best for promoting yeast growth and iron conversion. The siderophore-iron-enriched yeast (S-iron-enriched yeast) effectively restored the iron concentration, and an iron concentration of 59.40 mg/g was obtained by adding TZT-12. Iron deficiency anemia in rats was significantly mitigated with S-iron-enriched yeast compared with ferrous sulfate. These findings provide a new perspective on the preparation of organic trace elements for supplementation or food fortification.


Assuntos
Anemia Ferropriva , Oligoelementos , Anemia Ferropriva/tratamento farmacológico , Animais , Ferro , Ratos , Saccharomyces cerevisiae , Sideróforos
15.
ACS Appl Mater Interfaces ; 13(15): 18237-18246, 2021 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-33843205

RESUMO

Membrane separation has been considered as one of the most revolutionary technologies for the removal of oils, dyes, or other pollutants from wastewater. However, most membranes still face great challenges in water permeability, antifouling property, and even antibiotic ability. Possessing a pathogen-repellent surface is of great significance as it can enable membranes to minimize the presence of active viral pathogens. Herein, we demonstrate a distinct design with a molecular dynamics simulation-guided experiment for the surface domination of antibiotic zwitterionic nanogel membranes. The zwitterionic nanoparticle gel (ZNG)/Cu2+/glutaraldehyde (GA) synergy system is first simulated by introducing a ZNG into a preset CuCl2 brine solution and into a GA ethanol solution, in which the nanogel is observed to initially swell and subsequently shrink with the increase of GA concentration, leading to the membrane surface structure transition. Then, the corresponding experiments are performed under strict conditions, and the results suggest the surface structure transition from nanoparticles to network nanoflowers, which are consistent with the simulated results. The obtained network structure membrane with superhydrophilic and underwater superoleophobic abilities can significantly enhance the water permeability as high as almost 40% with its original rejection rate in comparison with unoptimizable ZNG-PVDF (polyvinylidene difluoride) membranes. Moreover, the obtained membrane achieves additional excellent antibiofouling capacity with the antibiotic efficiency exceeding 99.3%, manifesting remarkable potential for disinfection applications. By comparison, the conventional antibiotic methods generally improve the membrane's antibiotic property solely but can hardly improve the other properties of the membrane. That is to say, our simulation combined with the experimental strategy significantly improved the zwitterionic membrane property in this work, which provides a new perspective on the design of high-performance functional materials.

16.
Opt Lett ; 46(3): 681-684, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33528440

RESUMO

Efficient frequency conversion of photons has important applications in optical quantum technology because the frequency range suitable for photon manipulation and communication usually varies widely. Recently, an efficient frequency conversion system using a double-Λ four-wave mixing (FWM) process based on electromagnetically induced transparency (EIT) has attracted considerable attention because of its potential to achieve a nearly 100% conversion efficiency (CE). To obtain such a high CE, the spontaneous emission loss in this resonant-type FWM system must be suppressed considerably. A simple solution is to arrange the applied laser fields in a backward configuration. However, the phase mismatch due to this configuration can cause a significant decrease in CE. Here, we demonstrate that the phase mismatch can be effectively compensated by introducing the phase shift obtained by two-photon detuning. Under optimal conditions, we observe a wavelength conversion from 780 to 795 nm with a maximum CE of 91.2%±0.6% by using this backward FWM system at an optical depth of 130 in cold 87Rb atoms. The current work represents an important step toward achieving low-loss, high-fidelity quantum frequency conversion based on EIT.

17.
RSC Adv ; 11(27): 16268-16274, 2021 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-35479158

RESUMO

Membrane fouling has always been a tough issue that is urgent to solve. Electrolytes which are prevalent in wastewater have a major influence on membrane fouling. Therefore, it is of great significance to understand the role and fouling mechanism of electrolytes in the membrane fouling process. In this work, the zwitterionic membrane is used to process hydrolyzed poly(acrylamide) (HPAM) with the addition of electrolytes (CaCl2, NaCl). Meanwhile, the effect of different electrolytes on the zwitterionic membrane fouling process by hydrolyzed poly(acrylamide) (HPAM) is systematically investigated. It was found that the flux recovery ratio (FRR) of the zwitterionic membrane is nearly 100% after treating HPAM with the addition of electrolytes. Therefore, molecular dynamics (MD) simulations were applied to illustrate the impact of electrolytes on the change of foulant structures and confirm the consequent effect of electrolytes on membrane fouling. According to the experiment and MD simulation results, it is found that the positive ion layer which exists between the HPAM and zwitterionic surface results in the excellent fouling resistance performance of the zwitterionic membrane. The zwitterionic membrane fouling mechanism is analyzed, which is helpful to the understanding of zwitterionic membrane fouling in high salinity wastewater.

18.
Chin Med Sci J ; 36(4): 323-332, 2021 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-34986969

RESUMO

To get an optimal product of orthopaedic implant or regenerative medicine needs to follow trial-and-error analyses to investigate suitable product's material, structure, mechanical properites etc. The whole process from in vivo tests to clinical trials is expensive and time-consuming. Computational model is seen as a useful analysis tool to make the product development. A series of models for simulating tissue engineering process from cell attachment to tissue regeneration are reviewed. The challenging is that models for simulating tissue engineering processes are developed separately. From cell to tissue regeneration, it would go through blood injection after moving out the defect; to cell disperse and attach on the scaffold; to proliferation, migration and differentiation; and to the final part-becoming mature tissues. This paper reviewed models that related to tissue engineering process, aiming to provide an opportunity for researchers to develop a mature model for whole tissue engineering process. This article focuses on the model analysis methods of cell adhesion, nutrient transport and cell proliferation, differentiation and migration in tissue engineering. In cell adhesion model, one of the most accurate method is to use discrete phase model to govern cell movement and use Stanton-Rutland model for simulating cell attachment. As for nutrient transport model, numerical model coupling with volume of fluid model and species transport model together is suitable for predicting nutrient transport process. For cell proliferation, differentiation and migration, finite element method with random-walk algorithm is one the most advanced way to simulate these processes. Most of the model analysis methods require further experiments to verify the accuracy and effectiveness. Due to the lack of technology to detect the rate of nutrient diffusion, there are especially few researches on model analysis methods in the area of blood coagulation. Therefore, there is still a lot of work to be done in the research of the whole process model method of tissue engineering. In the future, the numerical model would be seen as an optimal way to investigate tissue engineering products bioperformance and also enable to optimize the parameters and material types of the tissue engineering products.


Assuntos
Engenharia Tecidual , Diferenciação Celular , Movimento Celular , Proliferação de Células , Simulação por Computador
19.
Tree Physiol ; 41(7): 1306-1318, 2021 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-33367887

RESUMO

Fruit semi-russeting is an undesirable quality trait that occurs in fruit production. It is reported that preharvest fruit bagging could effectively alleviate fruit exocarp semi-russeting, but the physiological and molecular mechanisms remain unclear. In the present study, we performed an in-depth investigation into pear fruit semi-russeting from morphologic, metabolic and transcriptomic perspectives by comparing control (semi-russeted) and bagged (non-russeted) 'Cuiguan' pear fruits. The results showed that significant changes in cutin and suberin resulted in pear fruit semi-russeting. Compared with the skin of bagged fruits, the skin of the control fruits presented reduced cutin contents accompanied by an accumulation of suberin, which resulted in fruit semi-russeting; α, ω-dicarboxylic acids accounted for the largest proportion of typical suberin monomers. Moreover, combined transcriptomic and metabolic analysis revealed a series of genes involved in cutin and suberin biosynthesis, transport and polymerization differentially expressed between the two groups. Furthermore, the expression levels of genes involved in the stress response and in hormone biosynthesis and signaling were significantly altered in fruits with contrasting phenotypes. Finally, a number of transcription factors, including those of the MYB, NAC, bHLH and bZIP families, were differentially expressed. Taken together, the results suggest that the multilayered mechanism through which bagging alleviates pear fruit semi-russeting is complex, and the large number of candidate genes identified provides a good foundation for future functional studies.


Assuntos
Pyrus , Frutas/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Fenótipo , Pyrus/genética , Transcriptoma
20.
Journal of Preventive Medicine ; (12): 250-254, 2021.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-876538

RESUMO

Objective@#To learn the awareness rate of adverse events following immunization ( AEFI ) among Chinese parents, so as to provide suggestions for promoting vaccination.@*Methods@#We searched relevant articles published before 24th June, 2020 from CNKI, Wanfang, VIP, CBM, PubMed and Web of Science, calculated the pooled awareness rate and 95% confidence interval ( CI ) , conducted Egger's test for publication bias and sensitivity analysis for stability of results. @*Results@#Eight articles using cross-sectional design were included after screening from 235 initial records. Among 5 433 subjects, the pooled awareness rate of AEFI was 66.76% ( 95%CI: 52.75%-78.33% ) . Non-immigrant population possessed a higher awareness rate ( 67.32% ) compared with the immigrant population ( 56.54% ) . The parents with different levels of education showed various awareness rate of AEFI ( P<0.05 ) . The awareness rates of "children should be observed for at least 30 minutes after vaccination","slight adverse effects were commonly seen after vaccination","local redness and induration might occur after diphtheria-tetanus-pertussis ( DTP ) immunization","polio vaccine might bring mild diarrhea" were 86.18%, 66.76%, 41.89% and 30.22%, respectively. Egger's test showed that there was no publication bias. Sensitivity analysis indicated that the results were robust.@*Conclusion@#The pooled awareness rate of AEFI among Chinese parents is 66.76%, with lower rates found in the parents who are immigrants and have lower level of education.

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