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1.
Small ; 20(16): e2307786, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38161248

RESUMO

To date, transforming environmental energy into electricity through a non-mechanical way is challenging. Herein, a series of photomechaelectric (PME) polyurethanes containing azobenzene-based photoisomer units and ionic liquid-based dipole units are synthesized, and corresponding PME nanogenerators (PME-NGs) to harvest electricity are fabricated. The dependence of the output performance of PME-NGs on the structure of the polyurethane is evaluated. The results show that the UV light energy can directly transduce into alternating-current (AC) electricity by PME-NGs via a non-mechanical way. The optimal open-circuit voltage and short-circuit current of PME-NGs under UV illumination reach 17.4 V and 696 µA, respectively. After rectification, the AC electricity can be further transformed into direct-current (DC) electricity and stored in a capacitor to serve as a power system to actuate typical microelectronics. The output performance of PME-NGs is closely related to the hard segment content of the PME polyurethane and the radius of counter anions in the dipole units. Kelvin probe force microscopy is used to confirm the existence of the PME effect and the detailed mechanism about the generation of AC electricity in PME-NGs is proposed, referring to the back and forth drift of induced electrons on the two electrodes in contact with the PME polyurethanes.

2.
Biopharm Drug Dispos ; 45(1): 58-68, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38319316

RESUMO

Renal function is an important factor affecting the pharmacokinetics of vancomycin. The renal function in elderly patients gradually decreases with age. An accurate estimated glomerular filtration rate (GFR) is essential in drug dosing. The study aimed to determine the most appropriate renal function estimation equations to describe vancomycin pharmacokinetics in elderly patients using population pharmacokinetic analysis. Data were obtained retrospectively from elderly patients aged ≥65 years who received vancomycin for infection from September 2016 to January 2022. Renal function was estimated using the Cockcroft-Gault equation (CG), Modification of Diet in Renal Disease equation (MDRD), three Chronic Kidney Disease Epidemiology Collaboration equations (CKD-EPIcys-scr , CKD-EPIscr , and CKD-EPIcys ) and two Berlin Initiative Study equations (BIS-1 and BIS-2). The CKD-EPIcys-scr and BIS-2 equations were based on cystatin C (Cys C) and serum creatinine (Scr). The others were based on Cys C or Scr. A nonlinear mixed effects model (NONMEM) was used to develop the population pharmacokinetic model. A total of 471 serum concentrations from 313 elderly patients were used to develop the population pharmacokinetic model. Weight and GFR were identified as significant covariates affecting the pharmacokinetics of vancomycin. Cys C and Scr-based GFR (CKD-EPIcys-scr and BIS-2) yielded significant improvement performance compared with the other equations in model building. The interindividual variability of CL was reduced from 49.4% to 23.6% and 49.4% to 23.7% in CKD-EPIcys-scr and BIS-2 based models, respectively. However, greater interindividual variabilities of CL (from 26.6% to 29.0%) were represented in the other five models which were based on either Cys C or Scr. The GFR estimated by EPIcys-scr and BIS-2 equations and vancomycin CL exhibited a good correlation (r = 0.834 and 0.833). In the external validation with 124 serum concentrations, the predictive performances of the CKD-EPIcys-scr and BIS-2 based models (the mean relative prediction errors were less than 1%, the mean relative absolute prediction errors were about 23%) were also superior to the other five models (the mean relative prediction errors were about 2%, the mean relative absolute prediction errors were greater than 25%) which are based on either Cys C or Scr. In this study, we determined that the equation used to estimate GFR can affect the population pharmacokinetic model fitting result. Population pharmacokinetics model with CKD-EPIcys-scr or BIS-2 can be used to optimize vancomycin dosage in elderly Chinese patients.


Assuntos
Taxa de Filtração Glomerular , Insuficiência Renal Crônica , Vancomicina , Idoso , Humanos , China , Creatinina , Cistatina C , Insuficiência Renal Crônica/metabolismo , Estudos Retrospectivos , Vancomicina/farmacocinética
3.
Opt Express ; 31(8): 12463-12470, 2023 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-37157405

RESUMO

We report on sub-40 fs pulse generation from a Yb:Sc2SiO5 laser pumped by a spatially single-mode fiber-coupled laser diode at 976 nm. A maximum output power of 545 mW was obtained at 1062.6 nm in the continuous-wave regime, corresponding to a slope efficiency of 64% and a laser threshold of 143 mW. A continuous wavelength tuning across 80 nm (1030 -1110 nm) was also achieved. Implementing a SESAM for starting and stabilizing the mode-locked operation, the Yb:Sc2SiO5 laser delivered soliton pulses as short as 38 fs at 1069.5 nm with an average output power of 76 mW at a pulse repetition rate of ∼79.8 MHz. The maximum output power was scaled to 216 mW for slightly longer pulses of 42 fs, which corresponded to a peak power of 56.6 kW and an optical efficiency of 22.7%. To the best of our knowledge, these results represent the shortest pulses ever achieved with any Yb3+-doped rare-earth oxyorthosilicate crystal.

4.
Opt Lett ; 48(17): 4544-4547, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37656549

RESUMO

We report on the spectral properties and laser performances of a novel, to the best of our knowledge, Tm,Ho:CaY0.9Lu0.1AlO4 (Tm,Ho:CYLA) crystal. The polarized absorption spectra, luminescence spectra, and fluorescence lifetime are systematically investigated, presenting a broad and smooth luminescence band. Furthermore, a maximum continuous wave (CW) laser output power of 0.51 W at 2092 nm is obtained under an absorbed pump power of 2.89 W, corresponding to a slope efficiency of 20.4%. The beam quality factors (M2) are measured to be 1.04 in both the x and y axes. A tuning range of 123.4 nm, from 2017.8 nm to 2141.2 nm, is achieved in the CW regime by using a birefringent filter (BF). A stable passively Q switched Tm,Ho:CYLA laser employing Cr2+:ZnSe as a saturable absorber (SA) is realized for the first time, delivering the shortest pulse width of 560 ns with a transmittance of 1%. The results indicate that the Tm,Ho:CYLA crystal is an excellent laser medium for generating high-efficiency laser at ∼2 µm and has a potential in ultrafast laser generation.

5.
J Child Psychol Psychiatry ; 64(12): 1652-1664, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37589403

RESUMO

STUDY OBJECTIVES: An evening circadian preference is common among adolescents. It is characterized by a behavioral predilection for later sleep and wake timing and is associated with higher rates of Major Depressive Disorder (MDD). The present study aims to (a) test the effectiveness of a cognitive behavioral sleep intervention (Transdiagnostic Sleep and Circadian Intervention; TranS-C) in a sample of adolescents with an evening circadian preference and clinically significant depressive symptoms and (b) evaluate improved alignment between circadian biology and sleep-wake behavior as a potential mechanism in the relationship between sleep and depression symptom improvement. METHODS: Adolescents with an evening circadian preference and clinically significant depressive symptoms were randomized to receive TranS-C (n = 24) or a psychoeducation condition (PE; n = 18). Alignment between circadian biology and sleep-wake behavior was measured using objective biological measurement. Measures of sleep and circadian rhythm were taken at pre- and posttreatment, and depression symptoms were measured at pre- and posttreatment and 6- and 12-month follow-up. RESULTS: Mixed effects modeling revealed that compared with an active control condition, TranS-C resulted in a significant reduction in MDD severity at 12-month follow-up. A MacArthur mediation analysis conducted to explore alignment between circadian biology and sleep-wake behavior as a mediator of depression severity reduction through 12-month follow-up revealed a significant interaction between change in alignment between circadian biology and sleep-wake behavior and treatment arm, indicating that improved alignment between circadian biology and sleep-wake behavior at posttreatment was associated with improvements in depression outcomes at 12-month follow-up under the treatment condition. CONCLUSIONS: These results provide novel evidence for improved alignment between circadian biology and sleep-wake behavior as a specific mechanism of depression improvement, provide key clues into the complex relationship between sleep and depression, and have significant clinical implications for adolescents with depression.


Assuntos
Transtorno Depressivo Maior , Transtornos do Sono-Vigília , Humanos , Adolescente , Depressão/terapia , Transtorno Depressivo Maior/terapia , Sono , Ritmo Circadiano , Biologia
6.
Biomed Chromatogr ; 37(3): e5572, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36520520

RESUMO

Valproic acid (VPA) is a classic medication for several types of epilepsy and mood disorders, and some of its effectiveness and toxicity is associated with metabolites. Although many reports have reported the drug-drug interactions of VPA, no study has focused on the influence of carbapenems (CBPMs) on VPA's active metabolites. An LC-MS/MS method for determining VPA and its six metabolites (3-hydroxy valproic acid, 4-hydroxy valproic acid, 2-propyl-2-pentenoic acid, 2-propyl-4-pentenoic acid, 3-keto valproic acid, and 2-propylglutaric acid) in human serum was established and applied to evaluate the drug-drug interaction with CBPMs in epileptic patients. The stable isotope valproic acid-d6 was used as an internal standard. Analytes in serum samples (50 µl) were isolated using a Kinetex C18 column (3 × 100 mm, 2.6 µm) and detected via negative electrospray ionization after protein precipitation. It was linear (r > 0.99) over the calibration range for different analytes. The accuracy was 91.44-110.92%, and the precision was less than 9.98%. The matrix effect, recovery, and stability met the acceptance criteria. According to the data collected from 150 epileptic patients, the concentration-dose ratio for VPA and its metabolites decreased with CBPM polytherapy. This method is simple and rapid with great accuracy and precision. It is suitable for routine clinical analysis of VPA and its metabolites in human serum.


Assuntos
Epilepsia , Ácido Valproico , Humanos , Carbapenêmicos/uso terapêutico , Cromatografia Líquida , Espectrometria de Massas em Tandem/métodos , Epilepsia/tratamento farmacológico , Anticonvulsivantes
7.
Molecules ; 28(3)2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36770809

RESUMO

Neuroblastoma has obvious heterogeneity. It is one of the few undifferentiated malignant tumors that can spontaneously degenerate into completely benign tumors. However, for its high-risk type, even with various intensive treatment options, the prognosis is still unsatisfactory. At the same time, a large number of research data show that the abnormal amplification and high-level expression of the MYCN gene are positively correlated with the malignant progression, poor prognosis, and mortality of neuroblastoma. In this context, this article explores the role of the N-Myc, MYCN gene expression product on its target genes related to the cell cycle and reveals its regulatory network in promoting tumor proliferation and malignant progression. We hope it can provide ideas and direction for the research and development of drugs targeting N-Myc and its downstream target genes.


Assuntos
Neuroblastoma , Proteínas Nucleares , Humanos , Proteínas Nucleares/metabolismo , Proteína Proto-Oncogênica N-Myc/genética , Proteína Proto-Oncogênica N-Myc/metabolismo , Genes myc , Ciclo Celular/genética , Neuroblastoma/patologia , Regulação Neoplásica da Expressão Gênica , Linhagem Celular Tumoral
8.
J Sci Food Agric ; 103(8): 3812-3821, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36268716

RESUMO

BACKGROUND: There is increasing interest in the development of oleogel-based emulsions. However, they usually contained surfactants for stabilization, especially small-molecular weight surfactants, which may have adverse health impacts. RESULTS: Herein, a surfactant-free oleogel-based emulsion stabilized by co-assembled ceramide/lecithin (CER/LEC) crystals was developed. The formation and stabilization mechanisms were explored. The different molar ratios of gelator (LEC and CER) in emulsions resulted in different crystal morphology, crystallinity as well as different emulsion properties. This suggested that appropriate crystallinity, crystal size, and interfacial distribution of these crystals provided higher surface coverage against droplets coalescence, thus better emulsion stabilization. Both X-ray diffractograms and contact angle results confirmed that the crystals which were primarily responsible for emulsion stabilization, are co-assembled crystals consisted of both gelators (CER and LEC). Furthermore, the percentage of free fatty acids (FFAs%) results revealed a negative relationship between lipid digestibility and crystal concentration. CONCLUSIONS: This strategy greatly enriched surfactant-free oleogel-based emulsion formulations, as well as their potential applications in healthy lipid-based products and novel food delivery systems with controlled lipid digestibility. © 2022 Society of Chemical Industry.


Assuntos
Lecitinas , Tensoativos , Lecitinas/química , Tensoativos/química , Emulsões/química , Ceramidas
9.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 45(2): 346-350, 2023 Apr.
Artigo em Zh | MEDLINE | ID: mdl-37157087

RESUMO

Wernekink commissure syndrome is a rare midbrain syndrome with bilateral cerebellar dysfunction,eye movement disorder,and palatal myoclonus.Few cases of this syndrome have been reported in China,let alone those combined with hallucinations and involuntary groping.This paper reports the diagnosis and treatment of a case of Wernekink commissure syndrome with hallucinations and involuntary groping,aiming to enrich the knowledge about this disease for clinicians.


Assuntos
Mesencéfalo , Transtornos da Motilidade Ocular , Humanos , Transtornos da Motilidade Ocular/diagnóstico , Medula Espinal , Síndrome , Alucinações
10.
Opt Lett ; 47(7): 1830-1833, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35363746

RESUMO

Molybdenum carbide (Mo2C) exhibits enormous potential applications in various optoelectronic and photonic fields due to its remarkably electrical and optical characteristics. Here, we fabricate a high-quality Mo2C film by the radio frequency magnetron sputtering deposition method. The nonlinear optical response and ultrafast dynamics are thoroughly studied based on open-aperture Z-scan and nondegenerate pump-probe experimental measurements. The open-aperture Z-scan experimental result exhibits a modulation depth of 8.5% and a saturation fluence of 0.28 mJ/cm2. Simultaneously, the relaxation time constant is fitted by a biexponential decay function, showing an ultrafast intraband carrier recovery time of 0.58 ps at 530 nm. Consequently, by employing the Mo2C film as a saturable absorber (SA), stable Q-switched Pr:YLF laser pulses with the shortest pulse width of 160 ns are generated at 639 nm. Our experimental results demonstrate excellent nonlinear optical properties of the layered Mo2C in the visible region and will further advance their potential applications in visible nonlinear optics.

11.
J Clin Pharm Ther ; 47(4): 483-492, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34779003

RESUMO

WHAT IS KNOWN AND OBJECTIVES: Ciclosporin (CsA), a potent immunosuppressive agent used to prevent graft-versus-host disease in allogeneic hematopoietic stem cell transplant (allo-HSCT) recipients, is characterized by large inter-individual variability and a narrow therapeutic range. The aim of this study was to develop a population pharmacokinetic model for CsA in Chinese allo-HSCT recipients and to identify covariates influencing CsA pharmacokinetics. METHODS: A total of 758 retrospective drug monitoring data points were collected after intravenous infusion or oral administration of CsA from 59 patients. Population pharmacokinetic analysis was performed using nonlinear mixed effects modelling expressed by differential equations. Monte Carlo simulation was applied to optimize dosage regimens. The final model was validated using bootstrap and normalized prediction distribution errors. RESULTS AND DISCUSSION: The results showed that the daily CsA dose, haematocrit, total bile acid, C-reactive protein (CRP) and co-administration of triazole antifungal agent were identified as significant covariates for clearance (CL) of CsA. The typical value of CL was 19.8 L/h with an inter-individual variability of 13.1%. The volume of distribution was 1340 L. Bioavailability was 67.2% with an inter-individual variability of 8.5%. Dosing simulation based on the developed model indicated that patients with high CRP concentration required a higher daily dose to attain the therapeutic trough concentration. The influence of CRP ultimately on the therapy outcome of CsA is not clear, which needs further study. WHAT IS NEW AND CONCLUSION: CRP concentration was identified as a novel marker associated with CsA pharmacokinetics, which should be considered when determining the appropriate dosage of CsA in allo-HSCT recipients.


Assuntos
Ciclosporina , Transplante de Células-Tronco Hematopoéticas , Proteína C-Reativa , Transplante de Células-Tronco Hematopoéticas/métodos , Humanos , Imunossupressores , Modelos Biológicos , Estudos Retrospectivos , Transplantados
12.
Xenobiotica ; 50(12): 1501-1509, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32453653

RESUMO

1. We aimed to establish a population pharmacokinetic (PK) model of tacrolimus and identify clinical covariates, especially the genetic polymorphisms of CYP3A5, ABCB1 and POR*28 that affected the PK to prevent fluctuation in the trough concentration of tacrolimus during the early period after renal transplantation. 2. Tacrolimus trough concentration, clinical data and CYP3A5/ABCB1/POR28 genotypes were retrospectively collected from 234 kidney transplant recipients during the first month post-transplantation. The population PK model was built using the non-linear mixed effects modeling software NONMEM. Dosing simulation was performed based on the final model. 3. A one-compartment model with first-order absorption and elimination was used to characterize the PK of tacrolimus. Among the genotypes, only CYP3A5 genotype was confirmed to have clinical significance. The final model describing CL/F (l/h) was as follows: 23.3 × ( HCT / 0.309 ) - 0.445   × [ ( 0.897 ,   i f   POD   > 10 ) o r   ( 1 , i f   POD   ≤ 10 ) ] × ( 0.657 , i f   CYP 3 A 5 * 3 / * 3   genotype ) . The inter-individual variability in CL/F was 21.9%. Monte Carlo simulation based on the final model was carried out to determine the optimal dosage regimen. 4. CYP3A5 genotype, post-operative day and hematocrit were confirmed as critical PK factors of tacrolimus. The model could be used to accurately predict individual PK parameters of tacrolimus and provide valuable insights into the dosage optimization.


Assuntos
Citocromo P-450 CYP3A/genética , Imunossupressores/farmacocinética , Tacrolimo/farmacocinética , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Humanos , Transplante de Rim , Polimorfismo de Nucleotídeo Único
13.
J Sci Food Agric ; 98(10): 3815-3822, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29352462

RESUMO

BACKGROUND: Postharvest diseases result in major losses in fruits. Tomato is susceptible to postharvest rot caused by Botrytis cinerea and is regarded as a good model system to study postharvest disease and quality deterioration in fruit. To develop a safe and effective technique to alleviate disease and maintain fruit quality, the effects of methyl salicylate (MeSA) and 1-methylcyclopropene (1-MCP) either separately or combined on quality and gray mold caused by B. cinerea in tomato fruit were investigated. RESULTS: The results showed that application of MeSA (0.05 mmol L-1 ) delayed fruit ripening and reduced gray mold. Compared with MeSA treatment, 1-MCP (0.5 µL L-1 ) effectively delayed fruit ripening. Further, MeSA combined with 1-MCP treatment was more effective in inhibiting fungal decay during storage than MeSA treatment alone. The combined treatment not only enhanced pathogenesis-related protein 1 (PR1) expression, activities of defense enzymes and total phenolic content but also inhibited the increase in electrical conductivity and malondialdehyde content. The combined treatment was also more effective in retaining firmness, color change and titratable acidity content than MeSA treatment alone. CONCLUSION: MeSA combined with 1-MCP treatment was a useful technique to maintain quality and alleviate gray mold in postharvest tomato fruit during storage. © 2018 Society of Chemical Industry.


Assuntos
Botrytis/efeitos dos fármacos , Ciclopropanos/farmacologia , Conservação de Alimentos/métodos , Conservantes de Alimentos/farmacologia , Frutas/microbiologia , Salicilatos/farmacologia , Solanum lycopersicum/química , Botrytis/fisiologia , Frutas/química , Solanum lycopersicum/microbiologia , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle
15.
Appl Opt ; 55(27): 7659-62, 2016 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-27661595

RESUMO

We experimentally demonstrated a diode-pumped 587 fs ultrafast laser by using an a-cut Nd:CaYAlO4 crystal. Pumped by an 808 nm fiber-coupled laser diode, a stable continuous-wave mode-locked ultrafast laser was achieved with a semiconductor saturable absorber. The ultrafast pulses had a repetition rate of 75 MHz at the center wavelength of 1080.8 nm. A maximum average output power of the mode-locked laser reached 375 mW delivering a slope efficiency of 9%.

16.
Bioorg Med Chem Lett ; 24(16): 4053-7, 2014 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-24986658

RESUMO

Three kinds of chitooligosaccharides (COS) with different degrees of deacetylation were prepared and named MD90, MD70 and MD50, respectively. Antioxidation, antiglycation and nitric oxide (NO) promotion in erythrocyte of these samples were investigated. The results showed that COS, especially MD90 had obviously inhibitory effects on oxidation and glycation. In addition, MD90 displayed stronger effect on increasing endogenous NO content than both MD70 and MD50, whose degrees of deacetylation were lower. The results indicated that amino group in COS has a certain effect on the activities of COS. As COS have a conformed activity to treat diabetes, the results of this study may be meaningful for further understanding the mechanism of the action.


Assuntos
Antioxidantes/farmacologia , Quitosana/farmacologia , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Óxido Nítrico/biossíntese , Oligossacarídeos/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Acetilação , Antioxidantes/síntese química , Antioxidantes/química , Quitosana/síntese química , Quitosana/química , Relação Dose-Resposta a Droga , Glicosilação/efeitos dos fármacos , Humanos , Oligossacarídeos/síntese química , Oligossacarídeos/química , Oxirredução/efeitos dos fármacos , Relação Estrutura-Atividade
17.
Environ Sci Pollut Res Int ; 31(1): 422-432, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38015407

RESUMO

UV/peroxymonosulfate (UV/PMS) is a promising advanced oxidation technology in water treatment. This study aimed to investigate the impact of UV/PMS on humic acid (HA) and the influence of PMS dosage, pretreatment time, pH pretreatment, nitrate, nitrite, ammonium, and bicarbonate influencing factors on disinfection byproduct (DBP) formation during post-chlorination. With increased PMS dosage or pretreatment time, the UV/PMS treatment significantly reduced ultraviolet absorbance and increased mineralization. It altered the fractional constituent as humic substances were gradually transformed into building blocks and low-molecular-weight acids. However, most DBP formation increased initially and then decreased after subsequent chlorination. Rising nitrate or nitrite concentrations markedly promoted halonitromethane (HNM) formation. The presence of ammonia had a more significant impact on dichloroacetonitrile (DCAN) formation. Bicarbonate in UV/PMS pretreatment increased carbonated disinfection byproduct (C-DBP) formation, whereas it had a negligible impact on nitrogenous disinfection byproduct (N-DBP) formation. The present study revealed the impact of a series of influencing factors on DBP formation in UV/PMS reaction systems, providing comprehensive insights on applying UV/PMS in actual practice.


Assuntos
Peróxidos , Poluentes Químicos da Água , Purificação da Água , Desinfecção , Substâncias Húmicas/análise , Halogenação , Nitratos , Nitritos , Bicarbonatos , Poluentes Químicos da Água/análise , Cloro/química
18.
Int J Biol Macromol ; 261(Pt 2): 129789, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38296127

RESUMO

Interactions between polysaccharides and ionic liquids (ILs) at the molecular level are essential to elucidate the dissolution and/or plasticization mechanism of polysaccharides. Herein, saccharide-based ILs (SILs) were synthesized, and cellulose membrane was soaked in different SILs to evaluate the interactions between SILs and cellulose macromolecules. The relevant results showed that the addition of SILs into cellulose can effectively reduce the intra- and/or inter-molecular hydrogen bonds of polysaccharides. Glucose-based IL showed the intensest supramolecular interactions with cellulose macromolecules compared to sucrose- and raffinose-based ILs. Two-dimensional correlation and perturbation-correlation moving window Fourier transform infrared techniques were for the first time used to reveal the dynamic variation of the supramolecular interactions between SILs and cellulose macromolecules. Except for the typical HO⋯H interactions of cellulose itself, stronger -Cl⋯HO hydrogen bonding interactions were detected in the specimen of SILs-modified cellulose membranes. Supramolecular interactions of -Cl⋯H, HO⋯H, C-Cl⋯H, and -C=O⋯H between SILs and cellulose macromolecules sequentially responded to the stimuli of temperature. This work provides a new perspective to understanding the interaction mechanism between polysaccharides and ILs, and an avenue to develop the next-generation ILs for dissolving or thermoplasticizing polysaccharide materials.


Assuntos
Líquidos Iônicos , Líquidos Iônicos/química , Imidazóis/química , Celulose/química , Polissacarídeos , Temperatura
19.
Mucosal Immunol ; 17(3): 450-460, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38101774

RESUMO

Colorectal cancer (CRC) ranks among the top causes of mortality globally. Gut inflammation is one crucial risk factor that augments CRC development since patients suffering from inflammatory bowel disease have an increased incidence of CRC. The role of immunoglobulin (Ig)A in maintaining gut homeostasis and preventing inflammation has been well established. Our earlier work demonstrated that the marginal zone and B1 cell-specific protein (MZB1) promotes gut IgA secretion and its absence results in pronounced dextran sulfate sodium salt (DSS)-induced colitis. In the present study, we explored the role of MZB1 in CRC development using the azoxymethane (AOM)/DSS-induced CRC model. We observed an increase in both the number and size of the tumor nodules in Mzb1-/- mice compared with Mzb1+/+ mice. The increase in CRC development and progression in Mzb1-/- mice was associated with reduced intestinal IgA levels, altered gut flora, and more severe gut and systemic inflammation. Oral administration of the monoclonal IgA, W27, alleviated both the gut inflammation and AOM/DSS-induced CRC. Notably, cohousing Mzb1+/+ and Mzb1-/- mice from the 10th day after birth led to similar CRC development. Our findings underscore the pivotal role of MZB1-mediated IgA secretion in suppressing the onset and progression of CRC triggered by gut inflammation. Moreover, our study highlights the profound impact of microbiota composition, modulated by gut IgA levels, on gut inflammation. Nonetheless, establishing a direct correlation between the severity of colitis and subsequent CRC development and the presence or absence of a particular microbiota is challenging.


Assuntos
Azoximetano , Colite , Neoplasias Colorretais , Sulfato de Dextrana , Modelos Animais de Doenças , Progressão da Doença , Microbioma Gastrointestinal , Camundongos Knockout , Animais , Humanos , Camundongos , Colite/induzido quimicamente , Colite/imunologia , Colite/metabolismo , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/etiologia , Neoplasias Colorretais/metabolismo , Imunoglobulina A/metabolismo , Imunoglobulina A/imunologia , Inflamação/imunologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/imunologia , Mucosa Intestinal/patologia , Camundongos Endogâmicos C57BL
20.
Blood Adv ; 8(7): 1667-1682, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38286463

RESUMO

ABSTRACT: Congenital neutropenia (CN) is a genetic disorder characterized by persistent or intermittent low peripheral neutrophil counts, thus increasing susceptibility to bacterial and fungal infections. Various forms of CN, caused by distinct genetic mutations, exhibit differential responses to granulocyte colony-stimulating factor (G-CSF) therapy, with the underlying mechanisms not fully understood. This study presents an in-depth comparative analysis of clinical and immunological features in 5 CN patient groups (severe congenital neutropenia [SCN]1, SCN3, cyclic neutropenia [CyN], warts, hypogammaglobulinaemia, infections and myelokathexis [WHIM], and Shwachman-Bodian-Diamond Syndrome [SBDS]) associated with mutations in ELANE, HAX1, CXCR4, and SBDS genes. Our analysis led to the identification of 11 novel mutations in ELANE and 1 each in HAX1, CXCR4, and G6PC3 genes. Investigating bone marrow (BM) granulopoiesis and blood absolute neutrophil count after G-CSF treatment, we found that SCN1 and SCN3 presented with severe early-stage disruption between the promyelocyte and myelocyte, leading to a poor response to G-CSF. In contrast, CyN, affected at the late polymorphonuclear stage of neutrophil development, showed a strong G-CSF response. WHIM, displaying normal neutrophil development, responded robustly to G-CSF, whereas SBDS, with moderate disruption from the early myeloblast stage, exhibited a moderate response. Notably, SCN1 uniquely impeded neutrophil development, whereas SCN3, CyN, WHIM, and SBDS also affected eosinophils and basophils. In addition, SCN1, SCN3, and CyN presented with elevated serum immunoglobulins, increased BM plasma cells, and higher A Proliferation-Inducing Ligand levels. Our study reveals a strong correlation between the stage and severity of granulocyte development disruption and the efficacy of G-CSF therapy.


Assuntos
Síndrome Congênita de Insuficiência da Medula Óssea , Eosinófilos , Fator Estimulador de Colônias de Granulócitos , Neutropenia/congênito , Humanos , Fator Estimulador de Colônias de Granulócitos/farmacologia , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Mutação , Proteínas Adaptadoras de Transdução de Sinal
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