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1.
Clin Neuropathol ; 2024 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-39355960

RESUMO

OBJECTIVE: This research aims to examine the expression of carbonic anhydrase IX (CAIX) protein in hemangioblastoma of the central nervous system and its potential application in pathological diagnosis and differential diagnosis. MATERIALS AND METHODS: Immunohistochemistry was used to identify the expression of CAIX and the α-inhibin protein. The sensitivity and specificity of CAIX and α-inhibin for identifying hemangioblastoma of the central nervous system were compared. In addition, 86 patients with meningiomas were gathered to detect CAIX protein expression. Hemangioblastoma and angiomatous, microcystic the two subtypes of meningiomas, were compared for CAIX and EMA protein expression. RESULTS: In hemangioblastoma, there were significant differences in the median positive percentage and staining intensity of CAIX and α-inhibin (p < 0.05). There was no discernible difference in the expression of the CAIX protein between sporadic hemangioblastoma of the central nervous system and those linked to von Hippel‒Lindau disease. In comparison to angiomatous and microcystic meningiomas, the positive rate of CAIX in hemangioblastomas was substantially greater (p < 0.001). The expression of EMA in microcystic meningioma (6/6) and angiomatous meningioma (17/17) was significantly different from hemangioblastoma (0/30) (p < 0.0001). CONCLUSION: Hemangioblastoma might be diagnosed with high specificity and sensitivity through CAIX immunohistochemistry. The combination of CAIX with EMA is useful for the diagnosis and differential diagnosis of hemangioblastoma.

2.
Adv Sci (Weinh) ; : e2405318, 2024 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-39356034

RESUMO

Chronic obstructive pulmonary disease (COPD) stands as the prevailing chronic airway ailment, characterized by chronic bronchitis and emphysema. Current medications fall short in treatment of these diseases, underscoring the urgent need for effective therapy. Prior research indicated immunoproteasome inhibition alleviated various inflammatory diseases by modulating immune cell functions. However, its therapeutic potential in COPD remains largely unexplored. Here, an elevated expression of immunoproteasome subunits LMP2 and LMP7 in the macrophages isolated from mouse with LPS/Elastase-induced emphysema and polarized macrophages in vitro is observed. Subsequently, intranasal administration of the immunoproteasome-specific inhibitor ONX-0914 significantly mitigated COPD-associated airway inflammation and improved lung function in mice by suppressing macrophage polarization. Additionally, ONX-0914 capsulated in PLGA nanoparticles exhibited more pronounced therapeutic effect on COPD than naked ONX-0914 by targeting immunoproteasome in polarized macrophages. Mechanistically, ONX-0914 activated autophagy and endoplasmic reticulum (ER) stress are not attribute to the ONX-0914 mediated suppression of macrophage polarization. Intriguingly, ONX-0914 inhibited M1 polarization through the nuclear factor erythroid 2-related factor-1 (NRF1) and NRF2-P62 axis, while the suppression of M2 polarization is regulated by inhibiting the transcription of interferon regulatory factor 4 (IRF4). In summary, the findings suggest that targeting immunoproteasome in macrophages holds promise as a therapeutic strategy for COPD.

4.
Front Oncol ; 14: 1380195, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39224807

RESUMO

Objective: The aim of this study was to compare hematological parameters pre- and early post-chemotherapy, and evaluate their values for predicting febrile neutropenia (FN). Methods: Patients diagnosed with malignant solid tumors receiving chemotherapy were included. Blood cell counts peri-chemotherapy and clinical information were retrieved from the hospital information system. We used the least absolute shrinkage and selection operator (LASSO) method for variable selection and fitted selected variables to a logistic model. We assessed the performance of the prediction model by the area under the ROC curve. Results: The study population consisted of 4,130 patients with common solid tumors receiving a three-week chemotherapy regimen in Sichuan Cancer Hospital from February 2019 to March 2022. In the FN group, change percentage of neutrophil count decreased less (-0.02, CI: -0.88 to 3.48 vs. -0.04, CI: -0.83 to 2.24). Among hematological parameters, lower post-chemotherapy lymphocyte count (OR 0.942, CI: 0.934-0.949), change percentage of platelet (OR 0.965, CI: 0.955-0.975) and higher change percentage of post-chemotherapy neutrophil count (OR 1.015, CI: 1.011-1.018), and pre-chemotherapy NLR (OR 1.002, CI: 1.002-1.002) predicted an increased risk of FN. These factors improved the predicting model based on clinical factors alone. The AUC of the combination model was 0.8275. Conclusion: Peri-chemotherapy hematological markers improve the prediction of FN.

5.
Angew Chem Int Ed Engl ; : e202415632, 2024 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-39269260

RESUMO

Despite recent advancements in inorganic and organic phosphors, creating monodisperse afterglow nanocomposites (NCs) remains challenging due to the complexities of wet chemistry synthesis. Inspired by nanoinclusions in opal, we introduce a novel SiO2-mediated carbon dot (CD) doping method for fabricating monodisperse, multifunctional afterglow NCs. This method involves growing a SiO2 shell matrix on monodisperse nanoparticles (NPs) and doping CDs into the SiO2 shell under hydrothermal conditions. Our approach preserves the monodispersity of the parent NP@SiO2 NCs while activating a green afterglow in the doped CDs with an impressive lifetime of 1.26 s. Additionally, this method is highly versatile, allowing for various core and dopant combinations to finely tune the afterglow through core-to-CD or CD-to-dye energy transfer. Our findings significantly enhance the potential of SiO2 coatings, transforming them from merely enhancing the biocompatibility of NCs to serving as a versatile matrix for emitters, facilitating afterglow generation and paving the way for new applications.

6.
Transl Cancer Res ; 13(8): 4042-4051, 2024 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-39262467

RESUMO

Background: The majority of small-sized (<3 cm) triple-negative breast cancer (TNBC) exhibit smooth margins upon palpation and are often oval or rounded masses. Distinguishing these masses preoperatively from fibroadenomas (FAs) would be very meaningful for clinical practice. The aim of our study was to evaluate the magnetic resonance imaging (MRI) appearance of TNBC and differentiate it from FAs. Methods: In this retrospective single-center study, we included 37 patients with TNBCs and 36 patients with FAs who underwent breast MRI. We employed the χ2 test and t-test to compare the differences in morphological features, dynamic contrast-enhanced MRI (DCE-MRI) parameters, and apparent diffusion coefficient (ADC) values between the two groups. Additionally, we constructed non-parametric receiver operating characteristic (ROC) curves using ADC values, with pathological results serving as the gold standard. Results: A total of 37 TNBC lesions and 39 FA lesions were included in the final analysis. TNBCs exhibited more frequent irregular shape, irregular margins, peritumoral edema, fast enhancement in the initial phase, rim enhancement, and time-signal intensity curve (TIC) type III compared to FAs (all P<0.05). Conversely, low-signal segregation in T2-weighted imaging (T2WI) and TIC type I were commonly found in FAs. The mean ADC value of TNBCs was significantly lower than that of FAs [(1.104±0.13)×10-3 vs. (1.613±0.16)×10-3 mm2/s, P<0.05]. The cutoff ADC for differentiating TNBCs from FAs was 1.239×10-3 mm2/s, yielding an area under the curve (AUC) of 0.997, a sensitivity of 94.6%, and a specificity of 100%. Conclusions: The morphological presentation of MRI, internal enhancement features of the mass, TIC curves, and ADC values provide valuable differential diagnostic information for TNBC and FA masses with a maximum diameter of less than 3 cm.

7.
Front Plant Sci ; 15: 1459505, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39253576

RESUMO

Anthocyanins are plant secondary metabolites belonging to the polyphenol class of natural water-soluble phytopigments. The accumulation of anthocyanins in different plant tissues can improve plant survival under adverse conditions. In addition, plants with the resulting colorful morphology can be utilized as landscape plants. Triticum boeoticum (syn. Triticum monococcum ssp. aegilopoides, 2n=2x=14, AbAb) serves as a valuable genetic resource for the improvement of its close relative common wheat in terms of enhancing resilience to various biotic and abiotic stresses. In our previous study, the EMS-mutagenized mutant Z2921 with a red glume, stem, and rachis was generated from T. boeoticum G52, which has a green glume, stem, and rachis. In this study, the F1, F2, and F2:3 generations of a cross between mutant-type Z2921 and wild-type G52 were developed. A single recessive gene, tentatively designated RgM4G52, was identified in Z2921 via genetic analysis. Using bulked segregant exome capture sequencing (BSE-Seq) analysis, RgM4G52 was mapped to chromosome 6AL and was flanked by the markers KASP-58 and KASP-26 within a 3.40-cM genetic interval corresponding to 1.71-Mb and 1.61-Mb physical regions in the Chinese Spring (IWGSC RefSeq v1.1) and Triticum boeoticum (TA299) reference genomes, respectively, in which seven and four genes related to anthocyanin synthesis development were annotated. Unlike previously reported color morphology-related genes, RgM4G52 is a recessive gene that can simultaneously control the color of glumes, stems, and rachis in wild einkorn. In addition, a synthetic Triticum dicoccum-T. boeoticum amphiploid Syn-ABAb-34, derived from the colchicine treatment of F1 hybrids between tetraploid wheat PI 352367 (T. dicoccum, AABB) and Z2921, expressed the red stems of Z2921. The flanking markers of RgM4G52 developed in this study could be useful for developing additional common wheat lines with red stems, laying the foundation for marker-assisted breeding and the fine mapping of RgM4G52.

8.
BMC Med Imaging ; 24(1): 252, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39304802

RESUMO

PURPOSE: To evaluate the predictive capabilities of MRI-based radiomics for detecting lymphovascular space invasion (LVSI) in patients diagnosed with endometrial carcinoma (EC). MATERIALS AND METHODS: A retrospective analysis was conducted on 160 female patients diagnosed with EC. The radiomics model including T2-weighted and dynamic contrast-enhanced MRI (DCE-MRI) images was established. Additionally, a conventional MRI model, which incorporated MRI-reported FIGO stage, deep myometrial infiltration (DMI), adnexal involvement, and vaginal/parametrial involvement, was established. Finally, a combined model was created by integrating the radiomics signature and conventional MRI characteristics. The predictive performance was validated by the area under the curve (AUC) of the receiver operating characteristic (ROC) curves. A stratified analysis was conducted to compare the differences between the three models by Delong test. RESULTS: In predicting LVSI, the radiomics model outperformed the clinical model in the training cohort (AUC: 0.899 vs. 0.8862) but not in the test cohort (AUC: 0.812 vs. 0.8758). The combined model demonstrated superior performance in both the training and test cohorts (training cohort: AUC = 0.934, 95% CI: 0.8807-0.9873; testing cohort: AUC = 0.905, 95% CI: 0.7679-1). CONCLUSIONS: The combined model exhibited utility in preoperatively predicting LVSI in patients with EC, offering potential benefits for clinical decision-making.


Assuntos
Neoplasias do Endométrio , Imageamento por Ressonância Magnética , Invasividade Neoplásica , Humanos , Feminino , Neoplasias do Endométrio/diagnóstico por imagem , Neoplasias do Endométrio/patologia , Neoplasias do Endométrio/cirurgia , Estudos Retrospectivos , Imageamento por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Idoso , Curva ROC , Metástase Linfática/diagnóstico por imagem , Imagem Multimodal/métodos , Adulto , Meios de Contraste , Radiômica
9.
J Exp Med ; 221(11)2024 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-39316084

RESUMO

The eye is closely connected to the brain, providing a unique window to detect pathological changes in the brain. In this study, we discovered ß-amyloid (Aß) deposits along the ocular glymphatic system in patients with Alzheimer's disease (AD) and 5×FAD transgenic mouse model. Interestingly, Aß from the brain can flow into the eyes along the optic nerve through cerebrospinal fluid (CSF), causing retinal degeneration. Aß is mainly observed in the optic nerve sheath, the neural axon, and the perivascular space, which might represent the critical steps of the Aß transportation from the brain to the eyes. Aquaporin-4 facilitates the influx of Aß in brain-eye transport and out-excretion of the retina, and its absence or loss of polarity exacerbates brain-derived Aß induced damage and visual impairment. These results revealed brain-to-eye Aß transport as a major contributor to AD retinopathy, highlighting a new therapeutic avenue in ocular and neurodegenerative disease.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Aquaporina 4 , Encéfalo , Sistema Glinfático , Camundongos Transgênicos , Degeneração Retiniana , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Animais , Peptídeos beta-Amiloides/metabolismo , Humanos , Degeneração Retiniana/metabolismo , Degeneração Retiniana/patologia , Encéfalo/metabolismo , Encéfalo/patologia , Camundongos , Aquaporina 4/metabolismo , Aquaporina 4/genética , Sistema Glinfático/metabolismo , Sistema Glinfático/patologia , Retina/metabolismo , Retina/patologia , Nervo Óptico/metabolismo , Nervo Óptico/patologia , Masculino , Feminino , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL , Idoso
10.
Nano Lett ; 24(38): 11929-11936, 2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39264715

RESUMO

Electrocatalytic nitrate (NO3-) reduction reaction (NO3-RR) represents a promising strategy for both wastewater treatment and ammonia (NH3) synthesis. However, it is difficult to achieve efficient NO3-RR on a single-component catalyst due to NO3-RR involving multiple reaction steps that rely on distinct catalyst properties. Here we report a facile alloying/dealloying-driven phase-separation strategy to construct a bimodal nanoporous Ag/Ag-Co tandem catalyst that exhibits a remarkable NO3-RR performance in a broad NO3- concentration range from 5 to 500 mM. In 10 and 50 mM NO3- electrolytes, the NH3 yield rates reach 3.4 and 25.1 mg h-1 mgcat.-1 with corresponding NH3 Faradaic efficiencies of 94.0% and 97.1%, respectively, outperforming most of the reported catalysts under the same NO3- concentration. The experimental results and density functional theory calculations demonstrate that Ag ligaments preferentially reduce NO3- to NO2-, while bimetallic Ag-Co ligaments catalyze the reduction of NO2- to NH3.

12.
Mucosal Immunol ; 2024 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-39251184

RESUMO

Postoperative cognitive dysfunction (POCD) is a prevalent neurological complication that can impair learning and memory for days, months, or even years after anesthesia/surgery. POCD is strongly associated with an altered composition of the gut microbiota (dysbiosis), but the accompanying metabolic changes and their role in gut-brain communication and POCD pathogenesis remain unclear. Here, the present study reports that anesthesia/surgery in aged mice induces elevated intestinal indoleamine 2,3-dioxygenase (IDO) expression and activity, which shifts intestinal tryptophan (TRP) metabolism toward more IDO-catalyzed kynurenine (KYN) and less gut bacteria-catabolized indoleacetic acid (IAA). Both anesthesia/surgery and intraperitoneal KYN administration induce increased KYN levels that correlate with impaired spatial learning and memory, whereas dietary IAA supplementation attenuates the anesthesia/surgery-induced cognitive impairment. Mechanistically, anesthesia/surgery increases interferon-γ (IFN-γ)-producing group 1 innate lymphoid cells (ILC1) in the small intestine lamina propria and elevates intestinal IDO expression and activity, as indicated by the higher ratio of KYN to TRP. The IDO inhibitor 1-MT and antibodies targeting IFN-γ or ILCs mitigate anesthesia/surgery-induced cognitive dysfunction, suggesting that intestinal ILC1 expansion and the ensuing IFN-γ-induced IDO upregulation may be the primary pathway mediating the shift to the KYN pathway in POCD. The ILC1-KYN pathway in the intestine could be a promising therapeutic target for POCD.

13.
Front Nutr ; 11: 1424334, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39346648

RESUMO

Objectives: The objective of this study was to investigate the effect of different harvest times and processing methods on the B vitamins and α-tocopherol contents of Leymus chinensis (Trin.). Methods: L. chinensis was harvested on 11 July (T1 group), 16 July (T2 group), 21 July (T3 group), 26 July (T4 group), and 31 July (T5 group) in 2022 and processed using natural drying and silage fermentation to evaluate fermentation quality, chemical composition, in vitro digestibility and vitamin content. Results: The fermentation quality of L. chinensis silage prepared at all five times of harvest was better. The silage fermentation group showed a significant increase (p < 0.05) in crude protein (CP), thiamin, riboflavin, pyridoxine and α-tocopherol content, a significant decrease (p < 0.05) in water-soluble carbohydrate (WSC) content, and small differences in neutral detergent fibre (NDF), acid detergent fibre (ADF), niacin and pantothenic acid content, when compared to the natural drying group. The content of thiamine, riboflavin, niacin, pantothenic acid and pyridoxine were higher in the pre-harvest period. In silage fermentation, the loss rate of thiamin, riboflavin and pyridoxine was positively correlated with pH and WSC, and the loss rate of thiamin and riboflavin was negatively correlated with lactic acid content. The loss rate of pantothenic acid was negatively correlated with pH and WSC, and positively correlated with lactic acid and ammonia nitrogen. The rate of α-tocopherol synthesis exceeded the rate of catabolism. Conclusion: The content of CP, thiamine, riboflavin, niacin, pantothenic acid and pyridoxine were higher during the early harvest period. Silage fermentation preserved the chemical composition and vitamin content of L. chinensis better than natural drying and had no effect on in vitro digestibility. During silage fermentation, the acidic environment promoted the preservation of thiamin, riboflavin and pyridoxine, but promoted the breakdown of pantothenic acid, α-tocopherol content increased through synthesis.

14.
Zool Res ; 45(6): 1188-1200, 2024 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-39318126

RESUMO

As an essential transcriptional activator, PDX1 plays a crucial role in pancreatic development and ß-cell function. Mutations in the PDX1 gene may lead to type 4 maturity-onset diabetes of the young (MODY4) and neonatal diabetes mellitus. However, the precise mechanisms underlying MODY4 remain elusive due to the paucity of clinical samples and pronounced differences in pancreatic architecture and genomic composition between humans and existing animal models. In this study, three PDX1-mutant cynomolgus macaques were generated using CRISPR/Cas9 technology, all of which succumbed shortly postpartum, exhibiting pancreatic agenesis. Notably, one tri-allelic PDX1-mutant cynomolgus macaque (designated as M4) developed a pancreas, whereas the two mono-allelic PDX1-mutant cynomolgus macaques displayed no anatomical evidence of pancreatic formation. RNA sequencing of the M4 pancreas revealed substantial molecular changes in both endocrine and exocrine functions, indicating developmental delay and PDX1 haploinsufficiency. A marked change in m6A methylation was identified in the M4 pancreas, confirmed through cultured PDX1-mutant islet organoids. Notably, overexpression of the m6A modulator METTL3 restored function in heterozygous PDX1-mutant islet organoids. This study highlights a novel role of m6A methylation modification in the progression of MODY4 and provides valuable molecular insights for preclinical research.


Assuntos
Proteínas de Homeodomínio , Macaca fascicularis , Pâncreas , Transativadores , Animais , Macaca fascicularis/genética , Transativadores/genética , Transativadores/metabolismo , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Mutação , Metilação , Feminino , Pancreatopatias/genética , Pancreatopatias/veterinária , Masculino , Doenças dos Macacos/genética
15.
Nano Lett ; 24(38): 12000-12009, 2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39259957

RESUMO

Graphene aerogels hold huge promise for the development of high-performance pressure sensors for future human-machine interfaces due to their ordered microstructure and conductive network. However, their application is hindered by the limited strain sensing range caused by the intrinsic stiffness of the porous microstructure. Herein, an anisotropic cross-linked chitosan and reduced graphene oxide (CCS-rGO) aerogel metamaterial is realized by reconfiguring the microstructure from a honeycomb to a buckling structure at the dedicated cross-section plane. The reconfigured CCS-rGO aerogel shows directional hyperelasticity with extraordinary durability (no obvious structural damage after 20 000 cycles at a directional compressive strain of ≤0.7). The CCS-rGO aerogel pressure sensor exhibits an ultrahigh sensitivity of 121.45 kPa-1, an unprecedented sensing range, and robust mechanical and electrical performance. The aerogel sensors are demonstrated to monitor human motions, control robotic hands, and even integrate into a flexible keyboard to play music, which opens a wide application potential in future human-machine interfaces.

17.
J Transl Med ; 22(1): 852, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39304928

RESUMO

BACKGROUND: The syncytiotrophoblast (SCT) layer in the placenta serves as a crucial physical barrier separating maternal-fetal circulation, facilitating essential signal and substance exchange between the mother and fetus. Any abnormalities in its formation or function can result in various maternal syndromes, such as preeclampsia. The transition of proliferative villous cytotrophoblasts (VCT) from the mitotic cell cycle to the G0 phase is a prerequisite for VCT differentiation and their fusion into SCT. The imprinting gene P57Kip2, specifically expressed in intermediate VCT capable of fusion, plays a pivotal role in driving this key event. Moreover, aberrant expression of P57Kip2 has been linked to pathological placental conditions and adverse fetal outcomes. METHODS: Validation of STK40 interaction with P57Kip2 using rigid molecular simulation docking and co-immunoprecipitation. STK40 expression was modulated by lentivirus in BeWo cells, and the effect of STK40 on trophoblast fusion was assessed by real-time quantitative PCR, western blot, immunofluorescence, and cell viability and proliferation assays. Co-immunoprecipitation, transcriptome sequencing, and western blot were used to determine the potential mechanisms by which STK40 regulates P57Kip2. RESULTS: In this study, STK40 has been identified as a novel interacting protein with P57Kip2, and its expression is down-regulated during the fusion process of trophoblast cells. Overexpressing STK40 inhibited cell fusion in BeWo cells while stimulating mitotic cell cycle activity. Further experiments indicated that this effect is attributed to its specific binding to the CDK-binding and the Cyclin-binding domains of P57Kip2, mediating the E3 ubiquitin ligase COP1-mediated ubiquitination and degradation of P57Kip2. Moreover, abnormally high expression of STK40 might significantly contribute to the occurrence of preeclampsia. CONCLUSIONS: This study offers new insights into the role of STK40 in regulating the protein-level homeostasis of P57Kip2 during placental development.


Assuntos
Fusão Celular , Inibidor de Quinase Dependente de Ciclina p57 , Proteínas Serina-Treonina Quinases , Trofoblastos , Ubiquitina-Proteína Ligases , Ubiquitinação , Feminino , Humanos , Gravidez , Proliferação de Células , Inibidor de Quinase Dependente de Ciclina p57/metabolismo , Inibidor de Quinase Dependente de Ciclina p57/genética , Ligação Proteica , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteólise , Trofoblastos/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina-Proteína Ligases/genética
18.
Langmuir ; 40(37): 19775-19786, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39226467

RESUMO

Carbonic anhydrase (CA) plays a crucial role in the CO2 capture processes by catalyzing the hydration of CO2. In this study, we synthesized a bioinspired carbonic anhydrase Zn-MOF (metal-organic framework) incorporating 2-aminoimidazole and Zn2+ as initial constituents. The synthesized Zn-MOF exhibited promising potential for efficiently catalyzing the CO2 hydration. Structural analyses such as SEM, XRD, and BET confirmed that the Zn-MOF crystal consisted of stacked grains with an average size of approximately 36 nm, forming a micron-sized spherical structure. Functionally, Zn-MOF exhibited effective catalytic activity toward both CO2 hydration and ester hydrolysis. The introduction of amino groups significantly enhanced the esterase activity of Zn-MOF to 0.28 U/mg at ambient temperature, which was twice that of ZIF-8. Furthermore, the introduction of amino groups resulted in remarkable hydrothermal stability, with the esterase activity reaching 0.72 U/mg after undergoing hydrothermal treatment at 80 °C for 12 h. Additionally, Zn-MOF exhibited enhanced capability in CO2 hydration at a pH value exceeding 8.5. After six repeated uses, ZIF-8 and Zn-MOF retained approximately 68 and 65% of their initial enzyme activity, respectively, underscoring the potential practical applicability of Zn-MOF in industrial CO2 capture processes. This work showcases the development of a novel Zn-MOF crystal as an efficient CA mimic, effectively emulating the active sites of natural CA using 2-aminoimidazole as a coordinating ligand for Zn2+ coordination. These findings not only advance the field of innovative enzyme mimics but also pave the way for further exploration of industrial CO2 capture catalysts.


Assuntos
Dióxido de Carbono , Anidrases Carbônicas , Imidazóis , Zinco , Anidrases Carbônicas/metabolismo , Anidrases Carbônicas/química , Imidazóis/química , Zinco/química , Dióxido de Carbono/química , Estruturas Metalorgânicas/química , Estruturas Metalorgânicas/síntese química , Materiais Biomiméticos/química , Materiais Biomiméticos/síntese química , Catálise , Esterases/química , Esterases/metabolismo
19.
Microsyst Nanoeng ; 10(1): 123, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39223148

RESUMO

Field-controlled micromanipulation represents a pivotal technique for handling microparticles, yet conventional methods often risk physical damage to targets. Here, we discovered a completely new mechanism for true noncontact manipulation through photothermal effects, called thermal-optical tweezers. We employ a laser self-assembly photothermal waveguide (PTW) for dynamic microparticle manipulation. This waveguide demonstrates superior photothermal conversion and precision control, generating a nonisothermal temperature field. The interaction of thermal convection and thermophoresis within this field creates a microfluidic potential well, enabling noncontact and nondestructive particle manipulation. By varying the path of PTWs in lithography and manipulating laser loading modes, diverse manipulation strategies, such as Z-shaped migration, periodic oscillation, and directional transport, are achievable. Our innovative noninvasive micromanipulation technology minimizes not only physical damage to target objects but also enables precise and diverse manipulation of micro entities, opening up new avenues for the photothermal control of cells and biomolecules.

20.
Mol Biol Evol ; 41(9)2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39248185

RESUMO

The heterogeneous landscape of genomic variation has been well documented in population genomic studies. However, disentangling the intricate interplay of evolutionary forces influencing the genetic variation landscape over time remains challenging. In this study, we assembled a chromosome-level genome for Castanopsis eyrei and sequenced the whole genomes of 276 individuals from 12 Castanopsis species, spanning a broad divergence continuum. We found highly correlated genomic variation landscapes across these species. Furthermore, variations in genetic diversity and differentiation along the genome were strongly associated with recombination rates and gene density. These results suggest that long-term linked selection and conserved genomic features have contributed to the formation of a common genomic variation landscape. By examining how correlations between population summary statistics change throughout the species divergence continuum, we determined that background selection alone does not fully explain the observed patterns of genomic variation; the effects of recurrent selective sweeps must be considered. We further revealed that extensive gene flow has significantly influenced patterns of genomic variation in Castanopsis species. The estimated admixture proportion correlated positively with recombination rate and negatively with gene density, supporting a scenario of selection against gene flow. Additionally, putative introgression regions exhibited strong signals of positive selection, an enrichment of functional genes, and reduced genetic burdens, indicating that adaptive introgression has played a role in shaping the genomes of hybridizing species. This study provides insights into how different evolutionary forces have interacted in driving the evolution of the genomic variation landscape.


Assuntos
Variação Genética , Seleção Genética , Evolução Molecular , Fluxo Gênico , Fagaceae/genética
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