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1.
Cell ; 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38968937

RESUMO

Immune tolerance mechanisms are shared in cancer and pregnancy. Through cross-analyzing single-cell RNA-sequencing data from multiple human cancer types and the maternal-fetal interface, we found B7-H4 (VTCN1) is an onco-fetal immune tolerance checkpoint. We showed that genetic deficiency of B7-H4 resulted in immune activation and fetal resorption in allogeneic pregnancy models. Analogously, B7-H4 contributed to MPA/DMBA-induced breast cancer progression, accompanied by CD8+ T cell exhaustion. Female hormone screening revealed that progesterone stimulated B7-H4 expression in placental and breast cancer cells. Mechanistically, progesterone receptor (PR) bound to a newly identified -58 kb enhancer, thereby mediating B7-H4 transcription via the PR-P300-BRD4 axis. PR antagonist or BRD4 degrader potentiated immunotherapy in a murine B7-H4+ breast cancer model. Thus, our work unravels a mechanistic and biological connection of a female sex hormone (progesterone) to onco-fetal immune tolerance via B7-H4 and suggests that the PR-P300-BRD4 axis is targetable for treating B7-H4+ cancer.

2.
Cell ; 182(2): 447-462.e14, 2020 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-32758418

RESUMO

The precise mechanism by which oral infection contributes to the pathogenesis of extra-oral diseases remains unclear. Here, we report that periodontal inflammation exacerbates gut inflammation in vivo. Periodontitis leads to expansion of oral pathobionts, including Klebsiella and Enterobacter species, in the oral cavity. Amassed oral pathobionts are ingested and translocate to the gut, where they activate the inflammasome in colonic mononuclear phagocytes, triggering inflammation. In parallel, periodontitis results in generation of oral pathobiont-reactive Th17 cells in the oral cavity. Oral pathobiont-reactive Th17 cells are imprinted with gut tropism and migrate to the inflamed gut. When in the gut, Th17 cells of oral origin can be activated by translocated oral pathobionts and cause development of colitis, but they are not activated by gut-resident microbes. Thus, oral inflammation, such as periodontitis, exacerbates gut inflammation by supplying the gut with both colitogenic pathobionts and pathogenic T cells.


Assuntos
Colite/patologia , Enterobacter/fisiologia , Microbioma Gastrointestinal , Klebsiella/fisiologia , Boca/microbiologia , Animais , Colite/microbiologia , Colo/microbiologia , Colo/patologia , Modelos Animais de Doenças , Enterobacter/isolamento & purificação , Feminino , Inflamassomos/metabolismo , Interleucina-10/deficiência , Interleucina-10/genética , Interleucina-1beta/metabolismo , Klebsiella/isolamento & purificação , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Periodontite/microbiologia , Periodontite/patologia , Células Th17/citologia , Células Th17/imunologia , Células Th17/metabolismo
3.
Lancet ; 403(10445): 2720-2731, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38824941

RESUMO

BACKGROUND: Anti-PD-1 therapy and chemotherapy is a recommended first-line treatment for recurrent or metastatic nasopharyngeal carcinoma, but the role of PD-1 blockade remains unknown in patients with locoregionally advanced nasopharyngeal carcinoma. We assessed the addition of sintilimab, a PD-1 inhibitor, to standard chemoradiotherapy in this patient population. METHODS: This multicentre, open-label, parallel-group, randomised, controlled, phase 3 trial was conducted at nine hospitals in China. Adults aged 18-65 years with newly diagnosed high-risk non-metastatic stage III-IVa locoregionally advanced nasopharyngeal carcinoma (excluding T3-4N0 and T3N1) were eligible. Patients were randomly assigned (1:1) using blocks of four to receive gemcitabine and cisplatin induction chemotherapy followed by concurrent cisplatin radiotherapy (standard therapy group) or standard therapy with 200 mg sintilimab intravenously once every 3 weeks for 12 cycles (comprising three induction, three concurrent, and six adjuvant cycles to radiotherapy; sintilimab group). The primary endpoint was event-free survival from randomisation to disease recurrence (locoregional or distant) or death from any cause in the intention-to-treat population. Secondary endpoints included adverse events. This trial is registered with ClinicalTrials.gov (NCT03700476) and is now completed; follow-up is ongoing. FINDINGS: Between Dec 21, 2018, and March 31, 2020, 425 patients were enrolled and randomly assigned to the sintilimab (n=210) or standard therapy groups (n=215). At median follow-up of 41·9 months (IQR 38·0-44·8; 389 alive at primary data cutoff [Feb 28, 2023] and 366 [94%] had at least 36 months of follow-up), event-free survival was higher in the sintilimab group compared with the standard therapy group (36-month rates 86% [95% CI 81-90] vs 76% [70-81]; stratified hazard ratio 0·59 [0·38-0·92]; p=0·019). Grade 3-4 adverse events occurred in 155 (74%) in the sintilimab group versus 140 (65%) in the standard therapy group, with the most common being stomatitis (68 [33%] vs 64 [30%]), leukopenia (54 [26%] vs 48 [22%]), and neutropenia (50 [24%] vs 46 [21%]). Two (1%) patients died in the sintilimab group (both considered to be immune-related) and one (<1%) in the standard therapy group. Grade 3-4 immune-related adverse events occurred in 20 (10%) patients in the sintilimab group. INTERPRETATION: Addition of sintilimab to chemoradiotherapy improved event-free survival, albeit with higher but manageable adverse events. Longer follow-up is necessary to determine whether this regimen can be considered as the standard of care for patients with high-risk locoregionally advanced nasopharyngeal carcinoma. FUNDING: National Natural Science Foundation of China, Key-Area Research and Development Program of Guangdong Province, Natural Science Foundation of Guangdong Province, Overseas Expertise Introduction Project for Discipline Innovation, Guangzhou Municipal Health Commission, and Cancer Innovative Research Program of Sun Yat-sen University Cancer Center. TRANSLATION: For the Chinese translation of the abstract see Supplementary Materials section.


Assuntos
Anticorpos Monoclonais Humanizados , Quimiorradioterapia , Quimioterapia de Indução , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Humanos , Pessoa de Meia-Idade , Masculino , Feminino , Carcinoma Nasofaríngeo/terapia , Carcinoma Nasofaríngeo/tratamento farmacológico , Adulto , China/epidemiologia , Neoplasias Nasofaríngeas/tratamento farmacológico , Neoplasias Nasofaríngeas/terapia , Quimiorradioterapia/métodos , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais Humanizados/efeitos adversos , Anticorpos Monoclonais Humanizados/administração & dosagem , Idoso , Cisplatino/uso terapêutico , Cisplatino/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Gencitabina , Desoxicitidina/análogos & derivados , Desoxicitidina/uso terapêutico , Desoxicitidina/administração & dosagem , Adulto Jovem , Adolescente , Intervalo Livre de Progressão
4.
Org Biomol Chem ; 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38953741

RESUMO

An efficient method for the construction of 5-arylpyrazolo[1,5-a]pyrimidines using calcium carbide as a solid alkyne source instead of flammable and explosive gaseous acetylene, pyrazole-3-amine and (hetero)aromatic aldehydes as starting materials in the presence of a copper mediator is described. Meanwhile, 2-arylpyrimido[1,2-b]indazoles are also synthesized under similar conditions using indazole-3-amine as a substitute for pyrazole-3-amine as a starting material. The method has salient features such as the use of an inexpensive and easy-to-handle alkyne source, commercially available substrates, wide functional group tolerance, a low-cost mediator, and simple workup procedures. This protocol can also be extended to gram-scale synthesis.

5.
Bioorg Med Chem ; 99: 117595, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38244254

RESUMO

Nicotinamide phosphoribosyltransferase (NAMPT) is a key rate-limiting enzyme in the nicotinamide adenine dinucleotide (NAD+) salvage pathway, primarily catalyzing the synthesis of nicotinamide mononucleotide (NMN) from nicotinamide (NAM), phosphoribosyl pyrophosphate (PRPP), and adenosine triphosphate (ATP). Metabolic diseases, aging-related diseases, inflammation, and cancers can lead to abnormal expression levels of NAMPT due to the pivotal role of NAD+ in redox metabolism, aging, the immune system, and DNA repair. In addition, NAMPT can be secreted by cells as a cytokine that binds to cell membrane receptors to regulate intracellular signaling pathways. Furthermore, NAMPT is able to reduce therapeutic efficacy by enhancing acquired resistance to chemotherapeutic agents. Recently, a few novel activators and inhibitors of NAMPT for neuroprotection and anti-tumor have been reported, respectively. However, NAMPT activators are still in preclinical studies, and only five NAMPT inhibitors have entered the clinical stage, unfortunately, three of which were terminated or withdrawn due to safety concerns. Novel drug design strategies such as proteolytic targeting chimera (PROTAC), antibody-drug conjugate (ADC), and dual-targeted inhibitors also provide new directions for the development of NAMPT inhibitors. In this perspective, we mainly discuss the structure, biological function, and role of NAMPT in diseases and the currently discovered activators and inhibitors. It is our hope that this work will provide some guidance for the future design and optimization of NAMPT activators and inhibitors.


Assuntos
NAD , Neoplasias , Humanos , NAD/metabolismo , Nicotinamida Fosforribosiltransferase , Citocinas/metabolismo , Niacinamida , Descoberta de Drogas , Neoplasias/tratamento farmacológico
6.
J Chem Phys ; 160(20)2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38804487

RESUMO

Lanthanide-doped upconversion (UC) luminescent materials display multicolor emissions, making them ideal for a variety of applications, such as multi-channel biological imaging, fluorescence encryption, anti-counterfeiting, and 3D display. Manipulating the UC emissions of the luminescent materials with a fixed composition is crucial for their applications. Herein, we propose a facile strategy to achieve pulse-width-dependent multicolor UC emissions in NaYF4:Yb/Er/Tm nanocrystals. Upon excitation with a 980 nm continuous-wave laser diode, Er3+ ions in NaYF4:20%Yb,15%Er,1%Tm nanocrystals exhibited UC emissions with a red-to-green (R/G) ratio of 11.3. Nevertheless, by employing a 980 nm pulse laser with pulse widths from 0.1 to 10 ms, the UC R/G ratio can be easily adjusted from 0.9 to 11.3, resulting in continuous and remarkable color transformation from green, yellow, orange, to red. By virtue of the dynamic luminescence color variation of these NaYF4:20%Yb,15%Er,1%Tm nanocrystals, we demonstrated their potential applications in the areas of anti-counterfeiting and information encryption. These findings provide deep insights into the excited-state dynamics and energy transfer of Er3+ in NaYF4:Yb/Er/Tm nanocrystals upon 980 nm pulse excitation, which may pave the way for designing multicolor UC materials toward versatile applications.

7.
Ecotoxicol Environ Saf ; 270: 115887, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38157803

RESUMO

Chronic noise exposure is correlated with gut microbiota dysbiosis and glucose and lipid metabolism disorders. However, evidence on the mechanisms underlying of gut microbiota alterations in chronic noise induced glucose and lipid metabolism disorders is limited, and the potential aftereffects of chronic noise exposure on metabolic disorders remain unclear. In present study, we established chronic daytime and nighttime noise exposure mice models to explore the effects and underlying mechanism of gut microbiota on chronic noise-induced glucose and lipid metabolism disorders. The results showed that exposure to chronic daytime or nighttime noise significantly increased the fasting blood glucose, serum and liver TG levels, impaired glucose tolerance, and decreased serum HDL-C levels and liver TC levels in mice. However, after 4 weeks of recovery, only serum TG of mice in nighttime noise recovery group remained elevated. Besides, exposure to chronic noise reduced the intestinal tight junction protein levels and increased intestinal permeability, while this effect did not completely dissipate even after the recovery period. Moreover, chronic noise exposure changed the gut microbiota and significantly regulated metabolites and metabolic pathways, and further activate hepatic gluconeogenesis CRTC2/CREB-PCK1 signaling pathway and lipid synthesis SREBP1/SCD signaling pathway through intestinal hepatic axis. Together, our findings demonstrated that chronic daytime and nighttime noise exposure could cause the glucose and lipid metabolism disorder by modulating the gut microbiota and serum metabolites, and activating hepatic gluconeogenic CREB/CRTC2-PCK1 signaling and lipid synthesis SREBP1/SCD signaling pathway. The potential aftereffects of noise exposure during wakefulness on metabolic disorders are more significant than that of noise exposure during sleep.


Assuntos
Microbioma Gastrointestinal , Transtornos do Metabolismo dos Lipídeos , Doenças Metabólicas , Animais , Camundongos , Metabolismo dos Lipídeos , Glucose/metabolismo , Fígado/metabolismo , Doenças Metabólicas/metabolismo , Lipídeos , Camundongos Endogâmicos C57BL
8.
Nano Lett ; 23(10): 4351-4358, 2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37156492

RESUMO

Luminescent metal halides have been exploited as a new class of X-ray scintillators for security checks, nondestructive inspection, and medical imaging. However, the charge traps and hydrolysis vulnerability are always detrimental to the three-dimensional ionic structural scintillators. Here, the two zero-dimensional organic-manganese(II) halide coordination complexes 1-Cl and 2-Br were synthesized for improvements in X-ray scintillation. The introduction of a polarized phosphine oxide can help to increase the stabilities, especially the self-absorption-free merits of these Mn-based hybrids. The X-ray dosage rate detection limits reached up to 3.90 and 0.81 µGyair/s for 1-Cl and 2-Br, respectively, superior to the medical diagnostic standard of 5.50 µGyair/s. The fabricated scintillation films were applied to radioactive imaging with high spatial resolutions of 8.0 and 10.0 lp/mm, respectively, holding promise for use in diagnostic X-ray medical imaging.

9.
Int J Mol Sci ; 25(10)2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38791345

RESUMO

Doxorubicin (DOX) is a potent chemotherapeutic agent known for its multi-organ toxicity, especially in the heart, which limits its clinical application. The toxic side effects of DOX, including DNA damage, oxidative stress, mitochondrial dysfunction and cell apoptosis, are intricately linked to the involvement of nicotinamide adenine dinucleotide (NAD+). To assess the effectiveness of the NAD+ precursor nicotinamide mononucleotide (NMN) in counteracting the multi-organ toxicity of DOX, a mouse model was established through DOX administration, which led to significant reductions in NAD+ in tissues with evident injury, including the heart, liver and lungs. NMN treatment alleviated both multi-organ fibrosis and mortality in mice. Mechanistically, tissue fibrosis, macrophage infiltration and DOX-related cellular damage, which are potentially implicated in the development of multi-organ fibrosis, could be attenuated by NAD+ restoration. Our findings provide compelling evidence for the benefits of NMN supplementation in mitigating the adverse effects of chemotherapeutic drugs on multiple organs.


Assuntos
Doxorrubicina , Fibrose , Mononucleotídeo de Nicotinamida , Animais , Doxorrubicina/efeitos adversos , Mononucleotídeo de Nicotinamida/farmacologia , Camundongos , Suplementos Nutricionais , Masculino , NAD/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia
10.
Angew Chem Int Ed Engl ; 63(7): e202318026, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38157447

RESUMO

The study of facile-synthesis and low-cost X-ray scintillators with high light yield, low detection limit and high X-ray imaging resolution plays a vital role in medical and industrial imaging fields. However, the optimal balance between X-ray absorption, decay lifetime and excitonic utilization efficiency of scintillators to achieve high-resolution imaging is extremely difficult due to the inherent contradiction. Here two thermally activated delayed fluorescence (TADF)-actived coinage-metal clusters M6 S6 L6 (M=Ag or Cu) were synthesized by simple solvothermal reaction, where the cooperation of heavy atom-rich character and TADF mechanism supports strong X-ray absorption and rapid luminescent collection of excitons. Excitingly, Ag6 S6 L6 (SC-Ag) displays a high photoluminescence quantum yield of 91.6 % and scintillating light yield of 17420 photons MeV-1 , as well as a low detection limit of 208.65 nGy s-1 that is 26 times lower than the medical standard (5.5 µGy s-1 ). More importantly, a high X-ray imaging resolution of 16 lp/mm based on SC-Ag screen is demonstrated. Besides, rigid core skeleton reinforced by metallophilicity endows clusters M6 S6 L6 strong resistance to humidity and radiation. This work provides a new view for the design of efficient scintillators and opens the research door for silver clusters in scintillation application.

11.
Lancet Oncol ; 24(6): 611-623, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37269842

RESUMO

BACKGROUND: The meta-analysis of chemotherapy for nasopharynx carcinoma (MAC-NPC) collaborative group previously showed that the addition of adjuvant chemotherapy to concomitant chemoradiotherapy had the highest survival benefit of the studied treatment regimens in nasopharyngeal carcinoma. Due to the publication of new trials on induction chemotherapy, we updated the network meta-analysis. METHODS: For this individual patient data network meta-analysis, trials of radiotherapy with or without chemotherapy in patients with non-metastatic nasopharyngeal carcinoma that completed accrual before Dec 31, 2016, were identified and updated individual patient data were obtained. Both general databases (eg, PubMed and Web of Science) and Chinese medical literature databases were searched. Overall survival was the primary endpoint. A frequentist network meta-analysis approach with a two-step random effect stratified by trial based on hazard ratio Peto estimator was used. Global Cochran Q statistic was used to assess homogeneity and consistency, and p score to rank treatments, with higher scores indicating higher benefit therapies. Treatments were grouped into the following categories: radiotherapy alone, induction chemotherapy followed by radiotherapy, induction chemotherapy without taxanes followed by chemoradiotherapy, induction chemotherapy with taxanes followed by chemoradiotherapy, chemoradiotherapy, chemoradiotherapy followed by adjuvant chemotherapy, and radiotherapy followed by adjuvant chemotherapy. This study is registered with PROSPERO, CRD42016042524. FINDINGS: The network comprised 28 trials and included 8214 patients (6133 [74·7%] were men, 2073 [25·2%] were women, and eight [0·1%] had missing data) enrolled between Jan 1, 1988, and Dec 31, 2016. Median follow-up was 7·6 years (IQR 6·2-13·3). There was no evidence of heterogeneity (p=0·18), and inconsistency was borderline (p=0·10). The three treatments with the highest benefit for overall survival were induction chemotherapy with taxanes followed by chemoradiotherapy (hazard ratio 0·75; 95% CI 0·59-0·96; p score 92%), induction chemotherapy without taxanes followed by chemoradiotherapy (0·81; 0·69-0·95; p score 87%), and chemoradiotherapy followed by adjuvant chemotherapy (0·88; 0·75-1·04; p score 72%), compared with concomitant chemoradiotherapy (p score 46%). INTERPRETATION: The inclusion of new trials modified the conclusion of the previous network meta-analysis. In this updated network meta-analysis, the addition of either induction chemotherapy or adjuvant chemotherapy to chemoradiotherapy improved overall survival over chemoradiotherapy alone in nasopharyngeal carcinoma. FUNDING: Institut National du Cancer and Ligue Nationale Contre le Cancer.


Assuntos
Quimiorradioterapia , Neoplasias Nasofaríngeas , Masculino , Humanos , Feminino , Carcinoma Nasofaríngeo/tratamento farmacológico , Metanálise em Rede , Quimioterapia Adjuvante , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimioterapia de Indução , Neoplasias Nasofaríngeas/tratamento farmacológico , Neoplasias Nasofaríngeas/radioterapia , Taxoides/uso terapêutico , Nasofaringe
12.
Semin Cancer Biol ; 86(Pt 3): 1143-1157, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-34182141

RESUMO

The intentional use of viruses for cancer therapy dates back over a century. As viruses are inherently immunogenic and naturally optimized delivery vehicles, repurposing viruses for drug delivery, tumor antigen presentation, or selective replication in cancer cells represents a simple and elegant approach to cancer treatment. While early virotherapy was fraught with harsh side effects and low response rates, virus-based therapies have recently seen a resurgence due to newfound abilities to engineer and tune oncolytic viruses, virus-like particles, and virus-mimicking nanoparticles for improved safety and efficacy. However, despite their great potential, very few virus-based therapies have made it through clinical trials. In this review, we present an overview of virus-inspired approaches for cancer therapy, discuss engineering strategies to enhance their mechanisms of action, and highlight their application for overcoming the challenges of traditional cancer therapies.


Assuntos
Nanopartículas , Neoplasias , Terapia Viral Oncolítica , Vírus Oncolíticos , Humanos , Vírus Oncolíticos/genética , Imunoterapia
13.
Small ; 19(42): e2302492, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37154205

RESUMO

Anisotropic charge transport plays a pivotal role in clarifying the conductivity mechanism in direct X-ray detection to improve the detection sensitivity. However, the anisotropic photoelectric effect of semiconductive single crystal responsive to X-ray is still lacking of theoretical and experimental proof. The semiconductive coordination polymers (CPs) with designable structures, adjustable functions, and high crystallinity provide a suitable platform for exploring the anisotropic conductive mechanism. Here,the study first reveals a 1D conductive transmission path for direct X-ray detection from the perspective of structural chemistry. The semiconductive copper(II)-based CP 1 single crystal detector exhibits unique anisotropic X-ray detection performance. Along the 1D π-π stacking direction, the single crystal device (1-SC-a) shows a superior sensitivity of 2697.15 µCGyair -1  cm-2 and a low detection limit of 1.02 µGyair  s-1 among CPs-based X-ray detectors. This study provides beneficial guidance and deep insight for designing high-performance CP-based X-ray detectors.

14.
Opt Lett ; 48(22): 5935-5938, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37966756

RESUMO

We present the design and fabrication of an on-chip FBG interrogator based on arrayed waveguide grating (AWG) technology. The spectral overlap between adjacent channels in the integrated AWG is significantly enhanced through a combination approach involving the reduction of the output waveguide spacing and an increase in the input waveguide width. As a result of these design choices, our AWG demonstrates excellent spectral consistency, with spectral cross talk exceeding 30 dB. The interrogator seamlessly combining optical and circuitry components achieves full integration and enables a wide range of interrogation wavelengths, including C-band and L-band. With an interrogation range extending up to 80 nm, it theoretically has the capacity to simultaneously interrogate the wavelengths of 20 FBG sensors. Experimental findings demonstrate an absolute interrogation accuracy of less than 2 pm for the fully integrated interrogator. With its compact size, cost-effectiveness, exceptional precision, and ease of integration, the proposed interrogator holds a substantial promise for widespread application in the realm of FBG sensing.

15.
Cell Mol Neurobiol ; 43(7): 3767-3781, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37526811

RESUMO

PPARγ coactivator-1 alpha (PGC-1α) is an essential transcription factor co-activator that regulates gene transcription and neural regeneration. Schwann cells, which are unique glial cells in peripheral nerves that dedifferentiate after peripheral nerve injury (PNI) and are released from degenerative nerves. Wallerian degeneration is a series of stereotypical events that occurs in response to nerve fibers after PNI. The role of PGC-1α in Schwann cell dedifferentiation and Wallerian degeneration is not yet clear. As Wallerian degeneration plays a crucial role in PNI, we conducted a study to determine whether PGC-1α has an effect on peripheral nerve degeneration after injury. We examined the expression of PGC-1α after sciatic nerve crush or transection using Western blotting and found that PGC-1α expression increased after PNI. Then we utilized ex vivo and in vitro models to investigate the effects of PGC-1α inhibition and activation on Schwann cell dedifferentiation and nerve degeneration. Our findings indicate that PGC-1α negatively regulates Schwann cell dedifferentiation and nerve degeneration. Through the use of RNA-seq, siRNA/plasmid transfection and reversal experiments, we identified that PGC-1α targets inhibit the expression of paraoxonase 1 (PON1) during Schwann cell dedifferentiation in degenerated nerves. In summary, PGC-1α plays a crucial role in preventing Schwann cell dedifferentiation and its activation can reduce peripheral nerve degeneration by targeting PON1. PGC-1α inhibits Schwann cell dedifferentiation and peripheral nerve degeneration. PGC-1α negatively regulates Schwann cell dedifferentiation and peripheral nerve degeneration after injury by targeting PON1.


Assuntos
Arildialquilfosfatase , Traumatismos dos Nervos Periféricos , Humanos , Arildialquilfosfatase/metabolismo , Arildialquilfosfatase/farmacologia , Desdiferenciação Celular , Degeneração Walleriana/metabolismo , Degeneração Walleriana/patologia , Células de Schwann , Nervo Isquiático/patologia , Traumatismos dos Nervos Periféricos/patologia , Regeneração Nervosa/fisiologia
16.
Virol J ; 20(1): 70, 2023 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-37072783

RESUMO

BACKGROUND: Since January 2020, measures has been adopted in the Chaoshan area to limit the spread of COVID-19. Restrictions were removed after August 2020. At the same time, children returned to school. We previously reported the changes of 14 main respiratory pathogens in hospitalized children before and during the COVID-19 outbreak in Chaoshan area. However, the changes of respiratory pathogen spectrum in hospitalized children after the epidemic are still unknown, which will be elucidated in this study. METHODS: There are 6201 children hospitalized with respiratory tract infection were enrolled in the study, which were divided into two groups: 2533 from outbreak group (1 January 2020-31 December 2020), and 3668 from post-outbreak group (1 January 2021-31 December 2021). Pharyngeal swab samples were collected. 14 respiratory tract pathogens were detected by liquid chip technology. RESULTS: The positive rate of pathogen detection is significantly lower in the outbreak group (65.42%, 1657/2533) than that in the post-outbreak group (70.39%, 2582/3668; χ2 = 17.15, P < 0.05). The Influenza A virus (FluA) detection rate was 1.9% (49) in 2020, but 0% (0) in 2021. The detection rates of Bordetella pertussis (BP) decreased from 1.4% (35) in 2020 to 0.5% (17) in 2021. In contrast, the detection rates of  Influenza B virus (FluB), Cytomegalovirus (CMV), Haemophilus influenzae (HI), Streptococcus pneumoniae (SP) increased from 0.3% (8), 24.7% (626), 2.0% (50) and 19.4% (491) in 2020 to 3.3% (121), 27.9% (1025), 4.6% (169), 22.8% (836) in 2021, respectively (P < 0.01). CONCLUSIONS: The detection rates of pathogens such as FluA, FluB, CMV, HI, SP, BP were statistically different between 2020 and 2021. From 2020 to 2021, the positive rates of Flu, CMV, HI and SP increased, while the positive rates of FluA and BP decreased. After the COVID-19 prevention and control measures are gradually relaxed, the positive rate of respiratory pathogens in children aged from 6 months to 6 years will increase.


Assuntos
COVID-19 , Infecções por Citomegalovirus , Infecções Respiratórias , Criança , Humanos , Lactente , Criança Hospitalizada , COVID-19/epidemiologia , Infecções Respiratórias/epidemiologia , Surtos de Doenças , Citomegalovirus , Infecções por Citomegalovirus/epidemiologia
17.
J Org Chem ; 88(21): 15151-15158, 2023 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-37851408

RESUMO

NHC-boranes have been treated as a reliable source of boryl radicals. In this study, regioselective hydroborylation of ketene dithioacetals with NHC-borane was achieved under mild conditions via a visible-light-promoted radical chain process using thiophenol as a proton donor and hydrogen atom transfer. This protocol features a low-cost catalyst, good functional group tolerance, a relatively broad range of substrate scope, and good to excellent yields. Moreover, mechanism of this hydroborylation reaction was preliminarily studied.

18.
Analyst ; 148(10): 2375-2386, 2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-37129055

RESUMO

Carbon dots (CDs) with red fluorescence emission are highly desirable for use in bioimaging and trace- substance detection, with potential applications in biotherapy, photothermal therapy, and tumor visualization. Most CDs emit green or blue fluorescence, thus limiting their applicability. We report a novel fluorescent detection platform based on high-brightness red fluorescence emission carbon dots (R-CDs) co-doped with nitrogen and bromine, which exhibit pH and oxidized L-glutathione (GSSG) dual-responsive characteristics. The absolute quantum yield of the R-CDs was as high as 11.93%. We discovered that the R-CDs were able to detect acidic pH in live cells and zebrafish owing to protonation and deprotonation. In addition, GSSG was detected in vitro over a broad linear range (8-200 µM) using the R-CDs with excitation-independent emission. Furthermore, cell imaging and bioimaging experiments demonstrated that the R-CDs were highly cytocompatible and could be used as fluorescent probes to target lysosomes and nucleolus. These studies highlight the promising prospects of R-CDs as biosensing tools for bioimaging and trace-substance detection applications.


Assuntos
Pontos Quânticos , Animais , Dissulfeto de Glutationa , Pontos Quânticos/química , Carbono/química , Peixe-Zebra , Corantes Fluorescentes/química , Nitrogênio/química , Concentração de Íons de Hidrogênio
19.
Analyst ; 148(11): 2564-2572, 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37158319

RESUMO

ß-Carotene is a natural antioxidant that has an indispensable effect on the growth and immunity of the human body. For intracellular and in vitro detection of ß-carotene, N-doped carbon quantum dots (O-CDs) were prepared by co-heating carbonization of 1,5-naphthalenediamine and nitric acid in ethanol solvent for 2 h at 200 °C. O-CDs have longer wavelength orange light emission, with an optimal excitation peak of 470 nm and an optimal emission peak of 590 nm. According to the principle of the internal filtering effect on which the detection system is based, O-CDs present a good linear relationship with ß-carotene within a wide range of 0-2000 µM, and the R2 coefficient of the linear regression equation is 0.999. In addition, O-CDs showed targeting of lysosomes in cell imaging and could be used to detect intracellular lysosomal movement. These experiments show that O-CDs can be used for in vivo and in vitro detection of ß-carotene and can serve as a potential substitute to commercial lysosome targeting probes.


Assuntos
Pontos Quânticos , beta Caroteno , Humanos , Carbono , Nitrogênio , Corantes Fluorescentes , Diagnóstico por Imagem
20.
Mol Cell Probes ; 72: 101931, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37683830

RESUMO

Although there are several treatments available for gastric cancer (GC), the prognosis of the disease is still poor due to many factors, such as late diagnosis and tumor heterogeneity. To identify potential therapeutic targets, bioinformatics techniques and clinical sample validation were employed and prostate transmembrane protein androgen induced 1 (PMEPA1) was selected for further study. In the present study, we found that elevated PMEPA1 expression correlates with a worse prognosis and weaker anti-tumor immunity in GC patients. Moreover, our study showed that PMEPA1 not only influences cell proliferation, clone formation, invasion, and migration in vitro, but also plays an important role in GC progression in vivo. Mechanically, PMEPA1 exerts its oncogenic effects through activating the Wnt/ß-catenin signaling pathway. Therefore, PMEPA1 is a potential target for treating GC effectively.


Assuntos
Neoplasias Gástricas , Masculino , Humanos , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Linhagem Celular Tumoral , Proteínas de Membrana/genética , Via de Sinalização Wnt , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica
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