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1.
J Biophotonics ; : e202400177, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38887864

RESUMO

The assessment of tumor grade and pathological stage plays a pivotal role in determining the treatment strategy and predicting the prognosis of endometrial cancer. In this study, we employed multiphoton microscopy (MPM) to establish distinctive optical pathological signatures specific to endometrioid adenocarcinoma (EAC), while also assessing the diagnostic sensitivity, specificity, and accuracy of MPM for this particular malignancy. The MPM technique exhibits robust capability in discriminating between benign hyperplasia and various grades of cancer tissue, with statistically significant differences observed in nucleocytoplasmic ratio and second harmonic generation/two-photon excited fluorescence intensity. Moreover, by utilizing semi-automated image analysis, we identified notable disparities in six collagen signatures between benign and malignant endometrial stroma. Our study demonstrates that MPM can differentiate between benign endometrial hyperplasia and EAC without labels, while also quantitatively assessing changes in the tumor microenvironment by analyzing collagen signatures in the endometrial stromal tissue.

2.
Chemistry ; : e202401436, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38869004

RESUMO

An efficient and rapid protocol for the oxidative halogenation of tryptamines with 10% aqueous NaClO has been developed. This reaction is featured by its operational simplicity, metal-free conditions, no purification, and high yield. Notably, the resulting key intermediates are suitable for further functionalization with various nucleophiles, including amines, N-aromatic heterocycles, indoles and phenols. The overall transformation exhibits broad functional-group tolerance and is applicable to the late-stage functionalization of complex biorelevant molecules.

3.
J Colloid Interface Sci ; 673: 26-36, 2024 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-38870665

RESUMO

Sb-based materials are considered as promising anode materials for sodium-ion batteries (SIBs) due to their excellent sodium storage capacities and suitable potentials. However, the Sb-based anodes usually suffer from intense volume expansion and severe pulverization during the alloying-dealloying process, resulting in poor cycling performance. Herein, a composite anode with Sb/Sb2O3 nanoparticles embedded in N-doped porous carbon is prepared by the gas-solid dual template method. The volume change of the anode material is mitigated by the carbon layer enwrapping and the confinement of the porous structure. Nitrogen doping provides abundant sodium storage sites, thus enhancing the storage capacity of sodium ion. Furthermore, to gain the accurate kinetic interpretation of the electrochemical process, an ex-situ transmission electron microscope (TEM) characterization combined with distribution of relaxation times (DRT) is conducted. The Sb/Sb2O3@NPC-1.0 demonstrates excellent electrochemical performance, achieving 340.3 mAh g-1 at 1A g-1, and maintains a capacity of 86.7 % after 1000 cycles. This work paves the way for the practical application of SIBs with high-performance and long-life Sb-based anodes.

4.
J Immunol ; 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38856632

RESUMO

Psoriasis is a common inflammatory skin disorder with no cure. Mesenchymal stem cells (MSCs) have immunomodulatory properties for psoriasis, but the therapeutic efficacies varied, and the molecular mechanisms were unknown. In this study, we improved the efficacy by enhancing the immunomodulatory effects of umbilical cord-derived MSCs (UC-MSCs). UC-MSCs stimulated by TNF-α and IFN-γ exhibited a better therapeutic effect in a mouse model of psoriasis. Single-cell RNA sequencing revealed that the stimulated UC-MSCs overrepresented a subpopulation expressing high tryptophanyl-tRNA synthetase 1 (WARS1). WARS1-overexpressed UC-MSCs treat psoriasis-like skin inflammation more efficiently than control UC-MSCs by restraining the proinflammatory macrophages. Mechanistically, WARS1 maintained a RhoA-Akt axis and governed the immunomodulatory properties of UC-MSCs. Together, we identify WARS1 as a master regulator of UC-MSCs with enhanced immunomodulatory capacities, which paves the way for the directed modification of UC-MSCs for escalated therapeutic efficacy.

5.
Sci Rep ; 14(1): 13192, 2024 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-38851826

RESUMO

Water eutrophication has emerged as a pressing concern for massive algal blooms, and these harmful blooms can potentially generate harmful toxins, which can detrimentally impact the aquatic environment and human health. Consequently, it is imperative to identify a safe and efficient approach to combat algal blooms to safeguard the ecological safety of water. This study aimed to investigate the procedure for extracting total flavonoids from Z. bungeanum residue and assess its antioxidant properties. The most favorable parameters for extracting total flavonoids from Z. bungeanum residue were a liquid-solid ratio (LSR) of 20 mL/g, a solvent concentration of 60%, an extraction period of 55 min, and an ultrasonic temperature of 80 °C. Meanwhile, the photosynthetic inhibitory mechanism of Z. bungeanum residue extracts against M. aeruginosa was assessed with a particular focus on the concentration-dependent toxicity effect. Z. bungeanum residue extracts damaged the oxygen-evolving complex structure, influenced energy capture and distribution, and inhibited the electron transport of PSII in M. aeruginosa. Furthermore, the enhanced capacity for ROS detoxification enables treated cells to sustain their photosynthetic activity. The findings of this study hold considerable relevance for the ecological management community and offer potential avenues for the practical utilization of resources in controlling algal blooms.


Assuntos
Flavonoides , Microcystis , Fotossíntese , Zanthoxylum , Flavonoides/química , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Zanthoxylum/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Antioxidantes/farmacologia , Antioxidantes/química , Antioxidantes/isolamento & purificação , Alelopatia , Proliferação Nociva de Algas , Espécies Reativas de Oxigênio/metabolismo , Complexo de Proteína do Fotossistema II/metabolismo
6.
Nat Commun ; 15(1): 4920, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38858353

RESUMO

The differentiation of the stroma is a hallmark event during postnatal uterine development. However, the spatiotemporal changes that occur during this process and the underlying regulatory mechanisms remain elusive. Here, we comprehensively delineated the dynamic development of the neonatal uterus at single-cell resolution and characterized two distinct stromal subpopulations, inner and outer stroma. Furthermore, single-cell RNA sequencing revealed that uterine ablation of Pr-set7, the sole methyltransferase catalyzing H4K20me1, led to a reduced proportion of the inner stroma due to massive cell death, thus impeding uterine development. By combining RNA sequencing and epigenetic profiling of H4K20me1, we demonstrated that PR-SET7-H4K20me1 either directly repressed the transcription of interferon stimulated genes or indirectly restricted the interferon response via silencing endogenous retroviruses. Declined H4K20me1 level caused viral mimicry responses and ZBP1-mediated apoptosis and necroptosis in stromal cells. Collectively, our study provides insight into the epigenetic machinery governing postnatal uterine stromal development mediated by PR-SET7.


Assuntos
Epigênese Genética , Histona-Lisina N-Metiltransferase , Células Estromais , Útero , Feminino , Animais , Útero/metabolismo , Células Estromais/metabolismo , Camundongos , Histona-Lisina N-Metiltransferase/metabolismo , Histona-Lisina N-Metiltransferase/genética , Interferons/metabolismo , Interferons/genética , Retrovirus Endógenos/genética , Apoptose/genética , Camundongos Endogâmicos C57BL , Morte Celular/genética , Necroptose/genética , Proteínas de Ligação a RNA/metabolismo , Proteínas de Ligação a RNA/genética , Histonas/metabolismo , Análise de Célula Única , Camundongos Knockout , Diferenciação Celular/genética
7.
Nat Commun ; 15(1): 5041, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38871694

RESUMO

Microspherical structures find broad application in chemistry and materials science, including in separations and purifications, energy storage and conversion, organic and biocatalysis, and as artificial and bioactive scaffolds. Despite this utility, the systematic diversification of their morphology and function remains hindered by the limited range of their molecular building blocks. Drawing upon the design principles of reticular synthesis, where diverse organic molecules generate varied porous frameworks, we show herein how analogous microspherical structures can be generated under mild conditions. The assembly of simple organic molecules into microspherical structures with advanced morphologies represents a grand challenge. Beginning with a partially condensed Schiff base which self-assembles into a hierarchical organic microsphere, we systematically synthesized sixteen microspheres from diverse molecular building blocks. We subsequently explicate the mechanism of hierarchical assembly through which these hierarchical organic microspheres are produced, isolating the initial monomer, intermediate substructures, and eventual microspheres. Furthermore, the open cavities present on the surfaces of these constructs provided distinctive adsorptive properties, which we harnessed for the immobilization of enzymes and bacteriophages. Holistically, these hierarchical organic microspheres provide an approach for designing multi-functional superstructures with advanced morphologies derived from simple organic molecules, revealing an extended length scale for reticular synthesis.

8.
Int Breastfeed J ; 19(1): 41, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38840129

RESUMO

BACKGROUND: Surgery is the primary treatment for benign breast disease and causes some disruption to the normal physiology of the breast, even when this disruption is localised, it remains unclear whether it affects women's ability to breastfeed. There are only a few studies describing the experience of breastfeeding in women who have undergone benign breast disease (BBD) surgery. METHODS: We retrospectively analysed data from patients aged 20-40 years in Guangdong, China, who underwent breast lumpectomy for BBD in our department between 01 January 2013 and 30 June 2019, with a follow-up date of 01 February 2022. Patients were included who had a history of childbirth between the time of surgery and the follow-up date. By collecting general information about this group of patients and information about breastfeeding after surgery, we described the breastfeeding outcomes of women of a fertile age who had previously undergone surgery for benign breast disease. RESULTS: With a median follow-up of 5.9 years, a total of 333 patients met the inclusion criteria. From the breastfeeding data of the first child born postoperatively, the mean duration of 'exclusive breastfeeding' was 5.1 months, and the mean duration of 'any breastfeeding' was 8.8 months. The rate of 'ever breastfeeding' is 91.0%, which is lower than the national average of 93.7%, while the exclusive breastfeeding rate at six months was 40.8%, was higher than the 29.2% national average. The any breastfeeding rate at 12 months was 30.0%, which was well below the 66.5% national average. The common reason for early breastfeeding cessation was insufficient breast milk. A total of 29.0% of patients who had ever breastfed after surgery voluntarily reduced the frequency and duration of breastfeeding on the operated breast because of the surgery. CONCLUSIONS: There are some impacts of BBD surgery on breastfeeding and some may be psychological. Institutions should provide more facilities for mothers who have undergone breast surgery to help them breastfeed, such as conducting community education on breastfeeding after breast surgery, training professional postoperative lactation consultants in hospitals, and extending maternity leave. Families should encourage mothers to breastfeed with both breasts instead of only the non-operated breast.


Assuntos
Doenças Mamárias , Aleitamento Materno , Humanos , Aleitamento Materno/psicologia , Aleitamento Materno/estatística & dados numéricos , Feminino , Adulto , Estudos Retrospectivos , Doenças Mamárias/cirurgia , Doenças Mamárias/psicologia , China/epidemiologia , Adulto Jovem , Inquéritos e Questionários
9.
Med Sci Monit ; 30: e943681, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38881074

RESUMO

BACKGROUND Over the past decades, total knee arthroplasty (TKA) in China has increased substantially. Owing to a lack of a joint registry, there is restricted information concerning the epidemiology of TKA failures in China. We aimed to (1) investigate the etiology of TKA failures in a cohort of Chinese patients and (2) determine the related demographic and anthropometric risk factors in Jilin, China, to have a look at the actual situation. MATERIAL AND METHODS A total of 1927 primary and 109 revision TKAs performed between April 2014 and May 2022 were analyzed in this retrospective study. Patient demographics and anthropometric measures, the interval from primary TKA to revision procedures, and the mechanisms for primary TKA failure were evaluated. A chi-square test, unpaired t test, and multivariate logistic regression were used to investigate the relationships between different factors and TKA failures. RESULTS The leading failure mechanism was infection (53.3%), followed by aseptic loosening (21.5%), stiffness (15.0%), instability (3.7%), malposition (2.8%), periprosthetic fractures (2.8%), and extensor mechanism disruption (0.9%). Infection (59.7%) was the main reason for early revision. Aseptic loosening (43.3%) was the leading cause of late revision. The male ratio in infection patients was higher (35.1% vs 20.6%). The smoking rate in patients with revision and infection was higher (18.9%, 23.9% vs 7%) than in primary patients. There was no difference in BMI between groups. CONCLUSIONS The leading cause of revision TKA in Jilin, China, was infection, followed by aseptic loosening and stiffness. Sex and smoking history were associated with TKA failures in this region.


Assuntos
Artroplastia do Joelho , Reoperação , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Artroplastia do Joelho/efeitos adversos , China/epidemiologia , População do Leste Asiático , Prótese do Joelho/efeitos adversos , Falha de Prótese , Reoperação/estatística & dados numéricos , Estudos Retrospectivos , Fatores de Risco
10.
Biomed Pharmacother ; 176: 116863, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38850650

RESUMO

Pyroptosis is a lytic and pro-inflammatory form of regulated cell death characterized by the formation of membrane pores mediated by the gasdermin protein family. Two main activation pathways have been documented: the caspase-1-dependent canonical pathway and the caspase-4/5/11-dependent noncanonical pathway. Pyroptosis leads to cell swelling, lysis, and the subsequent release of inflammatory mediators, including interleukin-1ß (IL-1ß) and interleukin-18 (IL-18). Chronic inflammation is a well-established foundation and driver for the development of metabolic diseases. Conversely, metabolic pathway dysregulation can also induce cellular pyroptosis. Recent studies have highlighted the significant role of pyroptosis modulation in various metabolic diseases, including type 2 diabetes mellitus, obesity, and metabolic (dysfunction) associated fatty liver disease. These findings suggest that pyroptosis may serve as a promising novel therapeutic target for metabolic diseases. This paper reviews an in-depth study of the current advancements in understanding the role of pyroptosis in the progression of metabolic diseases.


Assuntos
Doenças Metabólicas , Piroptose , Piroptose/fisiologia , Humanos , Doenças Metabólicas/metabolismo , Doenças Metabólicas/patologia , Animais , Transdução de Sinais , Inflamação/metabolismo , Inflamação/patologia
11.
Chemosphere ; 361: 142550, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38857633

RESUMO

Materials Institute Lavoisier (MIL) metal organic frameworks (MOFs) are known for their potential to adsorb gaseous organic pollutants. This study explores the synergistic effects between the selection of central metals (e.g., titanium, iron, and aluminum) and the incorporation of -NH2 groups in terms of adsorption efficiency against gaseous formaldehyde (FA). A group of the pristine MIL MOFs is synthesized using three different metals (i.e., titanium, iron, and aluminum) and terephthalic acid along with their NH2 derivatives using 2-aminoterephthalic acid. Among the pristine forms, MIL-125(Ti) achieves the highest FA adsorption capacity (Q) of 26.96 mg g-1 and a partition coefficient (PC) of 0.0898 mol kg-1 Pa-1. Further, amination significantly improves the FA adsorption potential of NH2-MIL-125(Ti) with a Q value of 91.22 mg g-1 (PC = 0.3038 mol kg-1 Pa-1). In situ diffuse reflectance infrared Fourier-transform spectroscopy reveals that the FA adsorption of plain MILs should be governed primarily by physisorption. In contrast, FA adsorption of NH2-MILs appears to be regulated by both physisorption and chemisorption, while the latter being affected mainly through FA-NH2 interactions (Schiff base reactions). These findings provide valuable insights into the utility of aminated MIL sorbents, possibly toward the efficient management of indoor air quality.


Assuntos
Poluentes Atmosféricos , Formaldeído , Estruturas Metalorgânicas , Formaldeído/química , Adsorção , Estruturas Metalorgânicas/química , Poluentes Atmosféricos/química , Titânio/química , Alumínio/química , Espectroscopia de Infravermelho com Transformada de Fourier , Ferro/química
12.
Environ Int ; 189: 108785, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38823155

RESUMO

Sex and thyroid hormones are critical for male reproductive health. However, the associations between haloacetic acid (HAA) exposure - a known endocrine disruptor - and sex and thyroid hormones in humans remains unclear. We thus recruited 502 male participants seeking fertility evaluation from a reproductive center. We measured concentrations of sex and thyroid hormones in a single blood sample and dichloroacetic acid (DCAA) and trichloroacetic acid (TCAA) in repeated urine samples. Multivariable linear regression models were constructed to evaluate the associations between HAA concentrations and hormone measurements. After adjusting for potential confounders and urinary creatinine concentrations, urinary concentrations of TCAA were inversely associated with serum levels of sex hormone-binding globulin (SHBG), testosterone (T), T/luteinizing hormone ratio (T/LH), and thyroid stimulating hormone (TSH) (all P for trend < 0.10). Compared with participants in the lowest quartile of TCAA concentrations, those in the highest quartile had reduced serum levels of SHGB by 14.2 % (95% CI: -26.7, -3.0 %), T by 11.1 % (95% CI: -21.7, -1.3 %), T/LH by 21.0 % (95% CI: -36.7, -7.1 %), and TSH by 19.1 % (95% CI: -39.7, -1.5 %). Additionally, we observed inverse associations between continuous measurements of urinary HAAs and serum levels of free T, bioactive T, and estradiol. Our findings suggest that male HAA exposure may be associated with disrupted sex and thyroid function.


Assuntos
Hormônios Tireóideos , Humanos , Masculino , Adulto , Hormônios Tireóideos/sangue , Testosterona/sangue , Testosterona/urina , Disruptores Endócrinos/urina , Disruptores Endócrinos/sangue , Globulina de Ligação a Hormônio Sexual/análise , Globulina de Ligação a Hormônio Sexual/metabolismo , Adulto Jovem , Ácido Tricloroacético/urina , Ácido Tricloroacético/sangue , Hormônio Luteinizante/sangue , Tireotropina/sangue , Exposição Ambiental/análise , Exposição Ambiental/estatística & dados numéricos , Pessoa de Meia-Idade , Hormônios Esteroides Gonadais/sangue , Hormônios Esteroides Gonadais/urina , Acetatos
13.
Dalton Trans ; 53(24): 10226-10234, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38828535

RESUMO

In aqueous solution, a novel triangle-like tungstovanadate estertin derivative K10H10.5[(W4O15(H2O)2){(SnCH2CH2COO)2(V0.75W10.75/V0.25O39)}{{(SnCH2CH2COO)2(µ-OH)}2(SnCH2CH2COO)(VW10O37)}2]·31H2O ((SnR)8-V3W35, R = CH2CH2COO) was assembled by a conventional synthetic method. (SnR)8-V3W35 is composed of one [VW11O39]7- ({VW11}) and two [VW10O37]9- ({VW10}) units connected by eight [Sn(CH2)2COO]2+ groups and a {W4O19} cluster. Interestingly, there exists a pentagonal bipyramid WO7 polyhedral center surrounded by two SnCO5 and three WO6 octahedra, forming a pentagonal {(WO7)W3(SnR)2} cluster in this polyoxometalate (POM), which is also the first example of a pentagonal structure formed by transition metals (TMs) and main group organometals in the POM family. Furthermore, the structure of this organic-inorganic hybrid POM also exhibits the largest number of organotin groups introduced into the POM system. It was characterized with various physico-chemical and spectroscopic methods, including X-ray single crystal and powder diffraction analysis, 119Sn and 51V NMR, IR, thermal gravimetric analysis (TGA), etc. In addition, the catalytic activity of (SnR)8-V3W35 as a mimic of peroxidase was evaluated using o-phenylenediamine (OPD) as a peroxidase substrate. The major factors influencing the oxidation reaction such as pH, the dosage of (SnR)8-V3W35, and concentrations of OPD and H2O2 were mainly studied. (SnR)8-V3W35 exhibits good peroxidase-like catalytic activity. From another perspective, the successful acquisition of (SnR)8-V3W35 further proves the instability and easy reassembly characteristics of TM-sandwich-type tungstovanadates, which also provides a new assembly strategy for synthesizing POM-estertin derivatives.

14.
J Glaucoma ; 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38884623

RESUMO

PRECIS: Wang et al compare an FDA-registered head-mounted smartphone device (PalmScan VF2000) with standard automated perimetry (SAP) in glaucoma patients and find that the head-mounted device may not fully recapitulate SAP testing. PURPOSE: This study prospectively compared visual field testing using the PalmScan VF2000 Visual Field Analyzer, a head-mounted smartphone device, with standard automated perimetry (SAP). METHODS: Patients with glaucoma undergoing Humphrey Field Analyzer SAP testing were asked to complete in-office PalmScan testing using a Samsung S5 smartphone in a virtual reality-style headset. Glaucoma severity was defined as SAP mean deviation (MD) >-6 dB for mild, between -6 and -12 dB for moderate, and <-12 dB for severe. Global parameters MD and pattern standard deviation (PSD) from PalmScan and SAP were compared using t-tests and Bland-Altman analyses. Bland-Altmann analyses of PalmScan and SAP MD were conducted for the superonasal, superotemporal, inferonasal, and inferotemporal visual field quadrants. The repeatability of PalmScan was assessed using Spearman's correlations and intraclass correlation coefficients (ICCs). RESULTS: Fifty-one patients (51 eyes) completed both SAP and PalmScan testing and met criteria for analysis. Compared to SAP, global MD and PSD measurements from PalmScan differed by an average of +0.62±0.26 dB (range: -3.25 to +4.60 dB) and -1.00±0.24 dB (range: -6.03 to +2.77 dB), respectively, while MD scores from individual visual field quadrants differed by as much as -6.58 to +11.43 dB. Agreement of PalmScan and SAP in classifying glaucoma severity was 86.3% across all eyes. PalmScan and SAP identified the same quadrant as having the worst visual field defect in 66.7% of eyes. CONCLUSIONS: Despite advantages in cost and accessibility, the PalmScan head-mounted perimetry device may not be able to fully recapitulate SAP testing.

15.
Opt Express ; 32(10): 17953-17965, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38858963

RESUMO

This article presents a dual-wavelength signal wave output system capable of generating a broad range of adjustable wavelength intervals. The setup involved the creation of a dual-wavelength cascaded Raman laser featuring composite cavities operating at 1176 nm and 1313 nm. Experimental investigations were carried out on an external cavity MgO:PPLN-OPO driven by the cascaded Raman laser. By setting the crystal polarization period to 27.6-34.4 µm and the temperature to 50-130°C, adjustable tunable output of dual-wavelength signal wave at 1176 nm-MgO:PPLN-OPO (1550-2294 nm) and 1313 nm-MgO:PPLN-OPO (1768-2189 nm) was achieved with a wavelength interval of 0-218 nm. Under the conditions of a period of 34.4 µm, temperature of 90°C, and an incident Raman power of 2.6 W, the highest conversion efficiency of Raman to dual-wavelength signal wave (2212, 2182 nm) was 34.2%. Furthermore, the maximum output power of dual-wavelength signal wave was recorded at 1.02 W with an incident Raman power of 3.33 W.

16.
Acta Pharm Sin B ; 14(6): 2598-2612, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38828149

RESUMO

Src homology 2 domain-containing tyrosine phosphatase 2 (SHP2) is an essential tyrosine phosphatase that is pivotal in regulating various cellular signaling pathways such as cell growth, differentiation, and survival. The activation of SHP2 has been shown to have a therapeutic effect in colitis and Parkinson's disease. Thus, the identification of SHP2 activators and a complete understanding of their mechanism is required. We used a two-step screening assay to determine a novel allosteric activator of SHP2 that stabilizes it in an open conformation. Oleanolic acid was identified as a suitable candidate. By binding to R362, K364, and K366 in the active center of the PTP domain, oleanolic acid maintained the active open state of SHP2, which facilitated the binding between SHP2 and its substrate. This oleanolic acid-activated SHP2 hindered Th17 differentiation by disturbing the interaction between STAT3 and IL-6Rα and inhibiting the activation of STAT3. Furthermore, via the activation of SHP2 and subsequent attenuation of the STAT3-Th17 axis, oleanolic acid effectively mitigated colitis in mice. This protective effect was abrogated by SHP2 knockout or administration of the SHP2 inhibitor SHP099. These findings underscore the potential of oleanolic acid as a promising therapeutic agent for treating inflammatory bowel diseases.

17.
J Am Chem Soc ; 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38832750

RESUMO

Dimerized quantum magnets are exotic crystalline materials where Bose-Einstein condensation of magnetic excitations can happen. However, known dimerized quantum magnets are limited to only a few oxides and halides. Here, we unveil 9 dimerized quantum magnets and 11 conventional antiferromagnets in ternary metal borides MTB4 (M = Sc, Y, La, Ce, Lu, Mg, Ca, and Al; T = V, Cr, Mn, Fe, Co, and Ni), where T atoms are arranged in structural dimers. Quantum magnetism in these compounds is dominated by strong antiferromagnetic (AFM) interactions between Cr (Cr and Mn for M = Mg and Ca) atoms within the dimers, with much weaker interactions between the dimers. These systems are proposed to be close to a quantum critical point between a disordered singlet spin-dimer phase, with a spin gap, and the ordered conventional Néel AFM phase. They greatly enrich the materials inventory that allows investigations of the spin-gap phase. Conventional antiferromagnetism in these compounds is dominated by ferromagnetic Mn (Fe for M = Mg and Ca) interactions within the dimers. The predicted stable and nonmagnetic (NM) YFeB4 phase is synthesized and characterized, providing a scarce candidate to study Fe dimers and Fe ladders in borides. The identified quantum, conventional, and NM systems provide a platform with abundant possibilities to tune the magnetic exchange coupling by doping and study the unconventional quantum phase transition and conventional magnetic transitions. This work opens new avenues for studying novel magnetism in borides arising from spin dimers and establishes a theoretical workflow for future searches for dimerized quantum magnets in other families of materials.

18.
J Transl Med ; 22(1): 419, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38702818

RESUMO

BACKGROUND: Glioblastoma is an aggressive brain tumor linked to significant angiogenesis and poor prognosis. Anti-angiogenic therapies with vascular endothelial growth factor receptor 2 (VEGFR2) inhibition have been investigated as an alternative glioblastoma treatment. However, little is known about the effect of VEGFR2 blockade on glioblastoma cells per se. METHODS: VEGFR2 expression data in glioma patients were retrieved from the public database TCGA. VEGFR2 intervention was implemented by using its selective inhibitor Ki8751 or shRNA. Mitochondrial biogenesis of glioblastoma cells was assessed by immunofluorescence imaging, mass spectrometry, and western blot analysis. RESULTS: VEGFR2 expression was higher in glioma patients with higher malignancy (grade III and IV). VEGFR2 inhibition hampered glioblastoma cell proliferation and induced cell apoptosis. Mass spectrometry and immunofluorescence imaging showed that the anti-glioblastoma effects of VEGFR2 blockade involved mitochondrial biogenesis, as evidenced by the increases of mitochondrial protein expression, mitochondria mass, mitochondrial oxidative phosphorylation (OXPHOS), and reactive oxygen species (ROS) production, all of which play important roles in tumor cell apoptosis, growth inhibition, cell cycle arrest and cell senescence. Furthermore, VEGFR2 inhibition exaggerated mitochondrial biogenesis by decreased phosphorylation of AKT and peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC1α), which mobilized PGC1α into the nucleus, increased mitochondrial transcription factor A (TFAM) expression, and subsequently enhanced mitochondrial biogenesis. CONCLUSIONS: VEGFR2 blockade inhibits glioblastoma progression via AKT-PGC1α-TFAM-mitochondria biogenesis signaling cascade, suggesting that VEGFR2 intervention might bring additive therapeutic values to anti-glioblastoma therapy.


Assuntos
Apoptose , Proliferação de Células , Glioblastoma , Mitocôndrias , Biogênese de Organelas , Receptor 2 de Fatores de Crescimento do Endotélio Vascular , Humanos , Glioblastoma/patologia , Glioblastoma/metabolismo , Glioblastoma/tratamento farmacológico , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Proliferação de Células/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Linhagem Celular Tumoral , Apoptose/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/tratamento farmacológico , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos
19.
Cell Rep ; 43(6): 114246, 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38762885

RESUMO

The decidua plays a crucial role in providing structural and trophic support to the developing conceptus before placentation. Following embryo attachment, embryonic components intimately interact with the decidual tissue. While evidence indicates the participation of embryo-derived factors in crosstalk with the uterus, the extent of their impact on post-implantation decidual development requires further investigation. Here, we utilize transgenic mouse models to selectively eliminate primary trophoblast giant cells (pTGCs), the embryonic cells that interface with maternal tissue at the forefront. pTGC ablation impairs decidualization and compromises decidual interferon response and lipid metabolism. Mechanistically, pTGCs release factors such as interferon kappa (IFNK) to strengthen the decidual interferon response and lipoprotein lipase (LPL) to enhance lipid accumulation within the decidua, thereby promoting decidualization. This study presents genetic and metabolomic evidence reinforcing the proactive role of pTGC-derived factors in mobilizing maternal resources to strengthen decidualization, facilitating the normal progression of early pregnancy.

20.
bioRxiv ; 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38712041

RESUMO

Spinal cord injuries (SCI) often lead to lifelong disability. Among the various types of injuries, incomplete and discomplete injuries, where some axons remain intact, offer potential for recovery. However, demyelination of these spared axons can worsen disability. Demyelination is a reversible phenomenon, and drugs like 4-aminopyridine (4AP), which target K+ channels in demyelinated axons, show that conduction can be restored. Yet, accurately assessing and monitoring demyelination post-SCI remains challenging due to the lack of suitable imaging methods. In this study, we introduce a novel approach utilizing the positron emission tomography (PET) tracer, [ 18 F]3F4AP, specifically targeting K+ channels in demyelinated axons for SCI imaging. Rats with incomplete contusion injuries were imaged up to one month post-injury, revealing [ 18 F]3F4AP's exceptional sensitivity to injury and its ability to detect temporal changes. Further validation through autoradiography and immunohistochemistry confirmed [ 18 F]3F4AP's targeting of demyelinated axons. In a proof-of-concept study involving human subjects, [ 18 F]3F4AP differentiated between a severe and a largely recovered incomplete injury, indicating axonal loss and demyelination, respectively. Moreover, alterations in tracer delivery were evident on dynamic PET images, suggestive of differences in spinal cord blood flow between the injuries. In conclusion, [ 18 F]3F4AP demonstrates efficacy in detecting incomplete SCI in both animal models and humans. The potential for monitoring post-SCI demyelination changes and response to therapy underscores the utility of [ 18 F]3F4AP in advancing our understanding and management of spinal cord injuries.

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