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1.
Development ; 150(21)2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37787076

RESUMO

Reciprocal interactions between non-myocytes and cardiomyocytes regulate cardiac growth and differentiation. Here, we report that the transcription factor Ebf1 is highly expressed in non-myocytes and potently regulates heart development. Ebf1-deficient hearts display myocardial hypercellularity and reduced cardiomyocyte size, ventricular conduction system hypoplasia, and conduction system disease. Growth abnormalities in Ebf1 knockout hearts are observed as early as embryonic day 13.5. Transcriptional profiling of Ebf1-deficient embryonic cardiac non-myocytes demonstrates dysregulation of Polycomb repressive complex 2 targets, and ATAC-Seq reveals altered chromatin accessibility near many of these same genes. Gene set enrichment analysis of differentially expressed genes in cardiomyocytes isolated from E13.5 hearts of wild-type and mutant mice reveals significant enrichment of MYC targets and, consistent with this finding, we observe increased abundance of MYC in mutant hearts. EBF1-deficient non-myocytes, but not wild-type non-myocytes, are sufficient to induce excessive accumulation of MYC in co-cultured wild-type cardiomyocytes. Finally, we demonstrate that BMP signaling induces Ebf1 expression in embryonic heart cultures and controls a gene program enriched in EBF1 targets. These data reveal a previously unreported non-cell-autonomous pathway controlling cardiac growth and differentiation.


Assuntos
Regulação da Expressão Gênica , Fatores de Transcrição , Animais , Camundongos , Diferenciação Celular/genética , Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Fatores de Transcrição/metabolismo
2.
Proc Natl Acad Sci U S A ; 120(49): e2305779120, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38011555

RESUMO

Using a longitudinal approach, we sought to define the interplay between genetic and nongenetic factors in shaping vulnerability or resilience to COVID-19 pandemic stress, as indexed by the emergence of symptoms of depression and/or anxiety. University of Michigan freshmen were characterized at baseline using multiple psychological instruments. Subjects were genotyped, and a polygenic risk score for depression (MDD-PRS) was calculated. Daily physical activity and sleep were captured. Subjects were sampled at multiple time points throughout the freshman year on clinical rating scales, including GAD-7 and PHQ-9 for anxiety and depression, respectively. Two cohorts (2019 to 2021) were compared to a pre-COVID-19 cohort to assess the impact of the pandemic. Across cohorts, 26 to 40% of freshmen developed symptoms of anxiety or depression (N = 331). Depression symptoms significantly increased in the pandemic years and became more chronic, especially in females. Physical activity was reduced, and sleep was increased by the pandemic, and this correlated with the emergence of mood symptoms. While low MDD-PRS predicted lower risk for depression during a typical freshman year, this genetic advantage vanished during the pandemic. Indeed, females with lower genetic risk accounted for the majority of the pandemic-induced rise in depression. We developed a model that explained approximately half of the variance in follow-up depression scores based on psychological trait and state characteristics at baseline and contributed to resilience in genetically vulnerable subjects. We discuss the concept of multiple types of resilience, and the interplay between genetic, sex, and psychological factors in shaping the affective response to different types of stressors.


Assuntos
COVID-19 , Pandemias , Feminino , Humanos , COVID-19/epidemiologia , COVID-19/genética , Ansiedade/epidemiologia , Ansiedade/genética , Transtornos de Ansiedade , Afeto , Depressão/epidemiologia , Depressão/genética
3.
Chem Soc Rev ; 53(13): 6960-6991, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38836431

RESUMO

The past few decades have witnessed encouraging progress in the development of high-performance film-based fluorescent sensors (FFSs) for detecting explosives, illicit drugs, chemical warfare agents (CWAs), and hazardous volatile organic chemicals (VOCs), among others. Several FFSs have transitioned from laboratory research to real-world applications, demonstrating their practical relevance. At the heart of FFS technology lies the sensing films, which play a crucial role in determining the analytes and the resulting signals. The selection of sensing fluorophores and the fabrication strategies employed in film construction are key factors that influence the fluorescence properties, active-layer structures, and overall sensing behaviors of these films. This review examines the progress and innovations in the research field of FFSs over the past two decades, focusing on advancements in fluorophore design and active-layer structural engineering. It underscores popular sensing fluorophore scaffolds and the dynamics of excited state processes. Additionally, it delves into six distinct categories of film fabrication technologies and strategies, providing insights into their advantages and limitations. This review further addresses important considerations such as photostability and substrate effects. Concluding with an overview of the field's challenges and prospects, it sheds light on the potential for further development in this burgeoning area.

4.
J Am Chem Soc ; 146(12): 8585-8597, 2024 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-38478659

RESUMO

Adjuvant treatment after surgical resection usually plays an important role in delaying disease recurrence. Immunotherapy displays encouraging results in increasing patients' chances of staying cancer-free after surgery, as reported by recent clinical trials. However, the clinical outcomes of current immunotherapy need to be improved due to the limited responses, patient heterogeneity, nontargeted distribution, and immune-related adverse effects. This work describes a programmable hydrogel adjuvant for personalized immunotherapy after surgical resection. By filling the hydrogel in the cavity, this system aims to address the limited secretion of granzyme B (GrB) during immunotherapy and improve the low immunotherapy responses typically observed, while minimizing immune-related side effects. The TLR7/8 agonist imidazoquinoline (IMDQ) is linked to the self-assembling peptide backbone through a GrB-responsive linkage. Its release could enhance the activation and function of immune cells, which will lead to increased secretion of GrB and enhance the effectiveness of immunotherapy together. The hydrogel adjuvant recruits immune cells, initiates dendritic cell maturation, and induces M1 polarized macrophages to reverse the immunosuppressive tumor microenvironment in situ. In multiple murine tumor models, the hydrogel adjuvant suppresses tumor growth, increases animal survival and long-term immunological memory, and protects mice against tumor rechallenge, leading to effective prophylactic and therapeutic responses. This work provides a potential chemical strategy to overcome the limitations associated with immunotherapy.


Assuntos
Hidrogéis , Neoplasias , Humanos , Animais , Camundongos , Imunoterapia/métodos , Neoplasias/terapia , Adjuvantes Imunológicos , Peptídeos , Microambiente Tumoral
5.
J Am Chem Soc ; 146(31): 21752-21761, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39056815

RESUMO

Organic polyradicals with a high-spin ground state and quantum magnetic properties suitable for spin manipulation are valuable materials for diverse innovative technologies, including quantum devices. However, the typically high reactivity and low stability of conventional polyradicals present a major obstacle to such applications. In this study, a highly stable carbon-centered triradical TR with a quartet ground state and excellent stability (τ1/2 of ∼90 days in air-saturated toluene at room temperature) is achieved, which shows apposite magnetic anisotropy and Zeeman splitting partition with favorable addressability. By virtue of the optimal stability, thorough structural and magnetic characterizations are realized. With X-ray crystallography unambiguously proving the molecular structure, the quartet ground state (ΔED-Q = 0.78 kcal/mol) is confirmed by the SQUID measurements, while the cw- and pulsed EPR techniques offer additional supportive evidence for the high-spin nature. Remarkably, owing to the easily attained magnetic anisotropy, selective excitations between different Zeeman splitting levels are successfully demonstrated with TR in its frozen toluene solution without the requirement for special alignment, which is unprecedented for organic polyradicals. Along with the millisecond spin-lattice relaxation and microsecond coherence time manifested by TR, this triradical is promising for potential coherent spin manipulation applications as a multienergy-level quantum information carrier.

7.
Br J Cancer ; 130(8): 1286-1294, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38388856

RESUMO

BACKGROUND: We characterized age at diagnosis and estimated sex differences for lung cancer and its histological subtypes among individuals who never smoke. METHODS: We analyzed the distribution of age at lung cancer diagnosis in 33,793 individuals across 8 cohort studies and two national registries from East Asia, the United States (US) and the United Kingdom (UK). Student's t-tests were used to assess the study population differences (Δ years) in age at diagnosis comparing females and males who never smoke across subgroups defined by race/ethnicity, geographic location, and histological subtypes. RESULTS: We found that among Chinese individuals diagnosed with lung cancer who never smoke, females were diagnosed with lung cancer younger than males in the Taiwan Cancer Registry (n = 29,832) (Δ years = -2.2 (95% confidence interval (CI):-2.5, -1.9), in Shanghai (n = 1049) (Δ years = -1.6 (95% CI:-2.9, -0.3), and in Sutter Health and Kaiser Permanente Hawai'i in the US (n = 82) (Δ years = -11.3 (95% CI: -17.7, -4.9). While there was a suggestion of similar patterns in African American and non-Hispanic White individuals. the estimated differences were not consistent across studies and were not statistically significant. CONCLUSIONS: We found evidence of sex differences for age at lung cancer diagnosis among individuals who never smoke.


Assuntos
Etnicidade , Neoplasias Pulmonares , Humanos , Masculino , Feminino , Estados Unidos/epidemiologia , Fumaça , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/epidemiologia , Neoplasias Pulmonares/patologia , China , Brancos
8.
Anal Chem ; 96(5): 2152-2157, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38279912

RESUMO

Sensing materials innovation plays a crucial role in the development of high-performance film-based fluorescent sensors (FFSs). In our current study, we present the innovative fabrication of four fluorescent nanofilms via interfacially confined dynamic reaction of a specially designed fluorescent building block, a new boron-coordinated compound (NI-CHO), with a chosen one, benzene-1,3,5-tricarbohydrazide (BTH). The nanofilms as prepared are robust, uniform, flexible, and thickness tunable, at least from 40 to 1500 nm. The fabricated FFSs based on Film 3, one of the four nanofilms, shows highly selective and fully reversible response to NH3 vapor with an experimental detection limit of <0.1 ppm and a response time of 0.2 s. The unprecedented high performance of the nanofilm is ascribed to the specific quenching of its fluorescence emission owing to formation of an excited-state complex between the sensing unit and the analyte molecule. Efficient mass transfer also contributes to the high performance owing to the porous adlayer structure of the nanofilm. This work provides an example to show how to develop a high-performance sensing film via controlling the film's structure, especially the thickness.

9.
Anal Chem ; 96(6): 2559-2566, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38302113

RESUMO

Ethephon (ETH) is widely used to promote fruit ripening and improve fruit quality. However, improper use is harmful to human health and to the environmental safety. Therefore, development of the techniques for on-site and at real-time monitoring of ETH is of importance for its safe use. In this work, we developed a nanofilm-based fluorescence film sensor (FFS) and realized highly efficient detection of ETH in vapor phase, where the detection limit (DL) is <0.2 ppb, the response time is less than 10 s, and the interference is almost free. The unusual sensing performance of the sensor was ascribed to the specific binding of the nanofilm to ETH and to its great porosity, which enables efficient adlayer mass transfer, a requirement for high signal-to-noise ratio. Moreover, visualization-based qualitative sensing is also realized. The nanofilm, a key component of the sensor, was prepared at the humid air/DMSO interface. The building blocks used were a specially designed fluorescent o-carborane derivative (CB-2CHO) and a cross-linker BTN possessing three acylhydrazine groups. The nanofilm as prepared is flexible, uniform, thickness tunable, and photochemically super stable. We believe our effort not only addresses the challenging issue of on-site and at real-time detection of ETH but also provides another route for developing new FFSs via sensing film innovation.

10.
Eur J Immunol ; 53(8): e2250221, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37137469

RESUMO

Rodent mast cells can be divided into two major subtypes: the mucosal mast cell (MMC) and the connective tissue mast cell (CTMC). A decade-old observation revealed a longer lifespan for CTMC compared with MMC. The precise mechanisms underlying such differential tissue persistence of mast cell subsets have not been described. In this study, we have discovered that mast cells expressing only one receptor, either FcγRIIB or FcγRIIIA, underwent caspase-independent apoptosis in response to IgG immune complex treatment. Lower frequencies of CTMC in mice that lacked either FcγRIIB or FcγRIIIA compared with WT mice were recorded, especially in aged mice. We proposed that this paradigm of FcγR-mediated mast cell apoptosis could account for the more robust persistence of CTMC, which express both FcγRIIB and FcγRIIIA, than MMC, which express only FcγRIIB. Importantly, we reproduced these results using a mast cell engraftment model, which ruled out possible confounding effects of mast cell recruitment or FcγR expression by other cells on mast cell number regulation. In conclusion, our work has uncovered an FcγR-dependent mast cell number regulation paradigm that might provide a mechanistic explanation for the long-observed differential mast cell subset persistence in tissues.


Assuntos
Mastócitos , Receptores de IgG , Camundongos , Animais , Receptores de IgG/genética , Receptores de IgG/metabolismo , Células do Tecido Conjuntivo/metabolismo , Tecido Conjuntivo/metabolismo , Apoptose
11.
Development ; 148(11)2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34100064

RESUMO

The most distal portion of the ventricular conduction system (VCS) contains cardiac Purkinje cells (PCs), which are essential for synchronous activation of the ventricular myocardium. Contactin-2 (CNTN2), a member of the immunoglobulin superfamily of cell adhesion molecules (IgSF-CAMs), was previously identified as a marker of the VCS. Through differential transcriptional profiling, we discovered two additional highly enriched IgSF-CAMs in the VCS: NCAM-1 and ALCAM. Immunofluorescence staining showed dynamic expression patterns for each IgSF-CAM during embryonic and early postnatal stages, but ultimately all three proteins became highly enriched in mature PCs. Mice deficient in NCAM-1, but not CNTN2 or ALCAM, exhibited defects in PC gene expression and VCS patterning, as well as cardiac conduction disease. Moreover, using ST8sia2 and ST8sia4 knockout mice, we show that inhibition of post-translational modification of NCAM-1 by polysialic acid leads to disrupted trafficking of sarcolemmal intercalated disc proteins to junctional membranes and abnormal expansion of the extracellular space between apposing PCs. Taken together, our data provide insights into the complex developmental biology of the ventricular conduction system.


Assuntos
Ventrículos do Coração/metabolismo , Moléculas de Adesão de Célula Nervosa/genética , Moléculas de Adesão de Célula Nervosa/metabolismo , Neurogênese/fisiologia , Molécula de Adesão de Leucócito Ativado , Animais , Moléculas de Adesão Celular/metabolismo , Contactina 2/metabolismo , Expressão Gênica , Coração , Sistema de Condução Cardíaco/metabolismo , Camundongos , Camundongos Knockout , Ácidos Siálicos , Sialiltransferases
12.
BMC Med ; 22(1): 68, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38360711

RESUMO

BACKGROUND: Follow-up visits for very preterm infants (VPI) after hospital discharge is crucial for their neurodevelopmental trajectories, but ensuring their attendance before 12 months corrected age (CA) remains a challenge. Current prediction models focus on future outcomes at discharge, but post-discharge data may enhance predictions of neurodevelopmental trajectories due to brain plasticity. Few studies in this field have utilized machine learning models to achieve this potential benefit with transparency, explainability, and transportability. METHODS: We developed four prediction models for cognitive or motor function at 24 months CA separately at each follow-up visits, two for the 6-month and two for the 12-month CA visits, using hospitalized and follow-up data of VPI from the Taiwan Premature Infant Follow-up Network from 2010 to 2017. Regression models were employed at 6 months CA, defined as a decline in The Bayley Scales of Infant Development 3rd edition (BSIDIII) composite score > 1 SD between 6- and 24-month CA. The delay models were developed at 12 months CA, defined as a BSIDIII composite score < 85 at 24 months CA. We used an evolutionary-derived machine learning method (EL-NDI) to develop models and compared them to those built by lasso regression, random forest, and support vector machine. RESULTS: One thousand two hundred forty-four VPI were in the developmental set and the two validation cohorts had 763 and 1347 VPI, respectively. EL-NDI used only 4-10 variables, while the others required 29 or more variables to achieve similar performance. For models at 6 months CA, the area under the receiver operating curve (AUC) of EL-NDI were 0.76-0.81(95% CI, 0.73-0.83) for cognitive regress with 4 variables and 0.79-0.83 (95% CI, 0.76-0.86) for motor regress with 4 variables. For models at 12 months CA, the AUC of EL-NDI were 0.75-0.78 (95% CI, 0.72-0.82) for cognitive delay with 10 variables and 0.73-0.82 (95% CI, 0.72-0.85) for motor delay with 4 variables. CONCLUSIONS: Our EL-NDI demonstrated good performance using simpler, transparent, explainable models for clinical purpose. Implementing these models for VPI during follow-up visits may facilitate more informed discussions between parents and physicians and identify high-risk infants more effectively for early intervention.


Assuntos
Doenças do Prematuro , Recém-Nascido Prematuro , Lactente , Criança , Recém-Nascido , Humanos , Estudos Retrospectivos , Estudos Longitudinais , Assistência ao Convalescente , Unidades de Terapia Intensiva Neonatal , Alta do Paciente
13.
Small ; 20(6): e2306195, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37789582

RESUMO

The poor reversibility and stability of Zn metal anode (ZMA) caused by uncontrolled Zn deposition behaviors and serious side reactions severely impeded the practical application of aqueous Zn metal battery. Herein, a liquid-dynamic and self-adaptive protective layer (LSPL) was constructed on the ZMA surface for inhibiting dendrites and by-products formation. Interestingly, the outer LSPL consists of liquid perfluoropolyether (PFPE), which can dynamically adapt volume change during repeat cycling and inhibit side reactions. Moreover, it can also decrease the de-solvation energy barrier of Zn2+ by strong interaction between C-F bond and foreign Zn2+ , improving Zn2+ transport kinetics. For the LSPL inner region, in-situ formed ZnF2 through the spontaneous chemical reaction between metallic Zn and part PFPE can establish an unimpeded Zn2+ migration pathway for accelerating ion transfer, thereby restricting Zn dendrites formation. Consequently, the LSPL-modified ZMA enables reversible Zn deposition/dissolution up to 2000 h at 1 mA cm-2 and high coulombic efficiency of 99.8% at 4 mA cm-2 . Meanwhile, LSPL@Zn||NH4 V4 O10 full cells deliver an ultralong cycling lifespan of 100 00 cycles with 0.0056% per cycle decay rate at 10 A g-1 . This self-adaptive layer provides a new strategy to improve the interface stability for next-generation aqueous Zn battery.

14.
Microvasc Res ; 153: 104658, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38266910

RESUMO

Endothelial permeability deterioration is involved in ventilator-induced lung injury (VILI). The integrality of vascular endothelial glycocalyx (EG) is closely associated with endothelial permeability. The hypothesis was that vascular EG shedding participates in VILI through promoting endothelial permeability. In the present study, male Sprague-Dawley (SD) rats were ventilated with high tidal volume (VT =40 ml/kg) or low tidal volume (VT =8 ml/kg) to investigate the effects of different tidal volume and ventilation durations on EG in vivo. We report disruption of EG during the period of high tidal volume ventilation characterized by increased glycocalyx structural components (such as syndecan-1, heparan sulfate, hyaluronan) in the plasma and decreased the expression of syndecan-1 in the lung tissues. Mechanistically, the disruption of EG was associated with increased proinflammatory cytokines and matrix metalloproteinase in the lung tissues. Collectively, these results demonstrate that the degradation of EG is involved in the occurrence and development of VILI in rats, and the inflammatory mechanism mediated by activation of the NF-κB signaling pathway may be partly responsible for the degradation of EG in VILI in rats. This study enhances our understanding of the pathophysiological processes underlying VILI, shedding light on potential therapeutic targets to mitigate VILI.


Assuntos
Sindecana-1 , Lesão Pulmonar Induzida por Ventilação Mecânica , Ratos , Masculino , Animais , Ratos Sprague-Dawley , Glicocálix/metabolismo , Lesão Pulmonar Induzida por Ventilação Mecânica/tratamento farmacológico , Lesão Pulmonar Induzida por Ventilação Mecânica/metabolismo , Pulmão/metabolismo
15.
Chemistry ; 30(15): e202303707, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38221317

RESUMO

Fluorogenic dyes with high brightness, large turn-on ratios, excellent photostability, favorable specificity, low cytotoxicity, and high membrane permeability are essential for high-resolution fluorescence imaging in live cells. In this study, we endowed these desirable properties to a rhodamine derivative by simply replacing the N, N-diethyl group with a pyrrole substituent. The resulting dye, Rh-NH, exhibited doubled Stokes shifts (54 nm) and a red-shift of more than 50 nm in fluorescence spectra compared to Rhodamine B. Rh-NH preferentially exists in a non-emissive but highly permeable spirolactone form. Upon binding to lysosomes, the collective effects of low pH, low polarity, and high viscosity endow Rh-NH with significant fluorescence turn-on, making it a suitable candidate for wash-free, high-contrast lysosome tracking. Consequently, Rh-NH enabled us to successfully explore stimulated emission depletion (STED) super-resolution imaging of lysosome dynamics, as well as fluorescence lifetime imaging of lysosomes in live cells.


Assuntos
Corantes Fluorescentes , Lisossomos , Humanos , Corantes Fluorescentes/química , Rodaminas/química , Lisossomos/química , Células HeLa , Microscopia de Fluorescência/métodos
16.
BMC Cancer ; 24(1): 476, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38622547

RESUMO

OBJECTIVE: Anxiety is a prevalent comorbidity in lung cancer (LC) patients associated with a decline in quality of life. Dehydroepiandrosterone (DHEA), a neuroactive steroid, levels rise in response to stress. Prior research on the association between DHEA and anxiety has yielded contradictory results and no study has investigated this association in LC patients. METHODS: A total of 213 patients with LC were recruited from a general hospital. Data on demographic and cancer-related variables were collected. Using the Chinese version of the Hospital Anxiety and Depression Scale (HADS), the degree of anxiety was determined. Cortisol, DHEA, and Dehydroepiandrosterone sulfate (DHEA-S) levels in saliva were measured. Adjusting for confounding variables, a multivariate regression analysis was conducted. RESULTS: 147 men and 66 women comprised our group with an average age of 63.75 years. After accounting for demographic and treatment-related factors, anxiety levels were significantly correlated with, post-traumatic stress symptoms (PTSSs) (ß = 0.332, p < 0.001) and fatigue (ß = 0.247, p = 0.02). Association between anxiety and three factors, including DHEA, PTSSs, and fatigue, was observed in patients with advanced cancer stages (III and IV) (DHEA ß = 0.319, p = 0.004; PTSS ß = 0.396, p = 0.001; fatigue ß = 0.289, p = 0.027) and those undergoing chemotherapy (DHEA ß = 0.346, p = 0.001; PTSS ß = 0.407, p = 0.001; fatigue ß = 0.326, p = 0.011). CONCLUSIONS: The association between anxiety and DHEA remained positive in advanced cancer stages and chemotherapy patients. Further study is necessary to determine whether DHEA is a potential biomarker of anxiety in LC patients.


Assuntos
Desidroepiandrosterona , Neoplasias Pulmonares , Masculino , Humanos , Feminino , Pessoa de Meia-Idade , Desidroepiandrosterona/análise , Sulfato de Desidroepiandrosterona/análise , Neoplasias Pulmonares/complicações , Qualidade de Vida , Ansiedade/epidemiologia , Hidrocortisona , Fadiga , Biomarcadores
17.
Biotechnol Bioeng ; 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39082641

RESUMO

d-Lactic acid holds significant industrial importance due to its versatility and serves as a crucial component in the synthesis of environmentally friendly and biodegradable thermal-resistant poly-lactic acid. This polymer exhibits promising potential as a substitute for nonbiodegradable, petroleum-based plastics. The production of d-lactic acid from lignocellulosic biomass, a type of biorenewable and nonfood resources, can lower costs and improve product competitiveness. Glucose and xylose are the most abundant sugar monomers in lignocellulosic biomass materials. Despite Escherichia coli possessing native xylose catabolic pathways and transport, their ability to effectively utilize xylose is often hindered in the presence of glucose. Here, the E. coli strain Rec1.0, previously engineered to overcome carbon catabolite repression, was selected as the initial strain for reengineering to produce d-lactic acid. An adaptive evolution approach was employed to achieve highly efficient fermentation of glucose-xylose mixtures. The resulting strain, QJL010, could produce d-lactic acid of 87.5 g/L with a carbon yield of 0.99 mol/mol. Notably, the consumption rates of glucose and xylose reached 0.75 and 0.82 g/gDCW/h, respectively. Further analysis revealed that increased Glk activity, resulting from glk mutations (A142V and R188H), along with their upregulated expression, contributed to an elevated glucose consumption rate. Additionally, a CRP G141D mutation, cAMP-independent, stimulated the expression of the xylR, xylE, and galABC* genes, resulting in an accelerated xylose consumption rate. These findings provide valuable support for the utilization of E. coli platform strains in the production of value-added chemicals from lignocellulosic biomass.

18.
Langmuir ; 40(32): 16946-16958, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39078939

RESUMO

Microgels have been widely used for stabilizing emulsions due to their softness and stimulus responsiveness. Although ultrastable emulsions have been prepared by microgel nanoparticles, the role of electrostatic interactions on emulsion stability is still a controversial topic and further investigation of the effect of microgel deformability is required. In the present study, neutral poly(N-vinylcaprolactam) (PVCL) and charged poly(N-vinylcaprolactam)-co-methacrylic acid (P(VCL-co-MAA)) microgels were synthesized and further used as emulsifiers to stabilizing emulsion. The P(VCL-co-MAA) microgel has a swelling ratio larger than that of the PVCL microgel in water. The nanomechanical properties of the microgels in water were characterized by atomic force microscopy with using the tip of different radii. The result reveals that the P(VCL-co-MAA) microgel is more deformable than the PVCL counterpart. Stability tests of the emulsions showed that below the volume phase transition temperature (VPTT) of the microgels, both microgel types can stabilize the emulsions under various conditions. Unexpectedly, most of the emulsions still remain stable above the VPTT. Further increasing the temperature to 60 °C, P(VCL-co-MAA) microgel emulsions remained stable at a pH value above the pKa of MAA while the emulsion was unstable below the pKa. However, phase separation occurs in PVCL microgel-stabilized emulsions at 60 °C. These results demonstrate that electrostatic repulsion and deformability of the microgels can enhance the emulsion stability, providing insights into the rational design and preparation of ultrastable Pickering emulsions.

19.
Langmuir ; 40(8): 4489-4495, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38369881

RESUMO

The efficient removal of radioactive iodine from an aqueous solution is largely dependent on the adsorbent materials employed. In this work, we report a calix[4]pyrrole-based nanofilm and its application for the rapid removal of iodine from water. The nanofilm was synthesized through a confined dynamic condensation of tetra hydrazide calix[4]pyrrole with 1,3,5-tri-(4-formylphenyl) aldehyde at the air/dimethyl sulfoxide (DMSO) interface. The thickness of the obtained nanofilm is ∼35 nm, enabling fast mass transfer and a high ratio of accessible binding sites for iodine. The pseudo-second-order rate constant of the nanofilm for iodine is ∼0.061 g g-1 min-1, 3 orders of magnitude higher than most reported adsorbent materials. Flow-through nanofiltration tests demonstrated that the nanofilm has an adsorption capacity of 1.48 g g-1, a high removal efficiency, and good reusability. The mechanism study revealed that the moieties of Schiff base, pyrrole, and aromatic rings play a key role for binding iodine. We believe this work provides not only a new strategy for the efficient removal of radioactive iodine from water but also new ideas for designing efficient iodine adsorbents.

20.
Diabetes Obes Metab ; 26(7): 2752-2760, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38618979

RESUMO

AIM: To assess the use of non-insulin antidiabetic medicines in China. MATERIALS AND METHODS: We analysed the national procurement data for 29 non-insulin antidiabetic medicines from nine subgroups in China from 2015 to 2022. We estimated the number of defined daily doses (DDDs) procured per year in seven regions of China for nine subgroups and adjusted the data by the number of patients with diabetes. For each subgroup, the regional ratio was calculated by comparing the procurement per patient in each region with the procurement nationwide. The regional disparity was the difference between the highest and lowest regional ratios. We compared the medication patterns across regions. RESULTS: Nationally, between 2015 and 2022, the number of DDDs per patient increased from 14.45 to 47.37. The two most commonly used categories were sulphonylurea and biguanides, which increased from 7.04 to 15.39 (119%) and 3.28 to 11.11 (239%) DDDs per patient, respectively. The procurement of new drugs (dipeptidyl peptidase-4 inhibitors, sodium-glucose cotransporter type 2 inhibitors and glucagon-like peptide-1 receptor agonists) increased quickly and had >5000% relative changes. Particularly for sodium-glucose cotransporter type 2 inhibitors, it increased from 0.08 to 5.03 DDDs (6662%). The southwest region had the highest relative change (319%), while the southern region had the lowest (118%). Biguanide and thiazolidinediones had the lowest (1.19) and highest level (2.21) of regional disparity in 2022, respectively. CONCLUSION: The procurement of non-insulin antidiabetic medicines in China has increased a lot from 2015 to 2022. In terms of DDDs per patient, sulphonylurea ranked first, followed by metformin. The procurement of new drugs increased greatly. A large regional disparity existed in medicine usage and patterns.


Assuntos
Diabetes Mellitus Tipo 2 , Hipoglicemiantes , Humanos , China , Hipoglicemiantes/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Biguanidas/uso terapêutico , Inibidores da Dipeptidil Peptidase IV/uso terapêutico , Compostos de Sulfonilureia/uso terapêutico , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Uso de Medicamentos/tendências , Uso de Medicamentos/estatística & dados numéricos , Diabetes Mellitus/tratamento farmacológico , Diabetes Mellitus/epidemiologia
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