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1.
BMC Infect Dis ; 24(1): 560, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38840046

RESUMO

BACKGROUND: China experienced an overwhelming COVID-19 pandemic from middle December 2022 to middle January 2023 after lifting the zero-COVID-19 policy on December 7, 2022. However, the infection rate was less studied. We aimed to investigate the SARS-CoV-2 infection rate in children shortly after discontinuation of the zero-COVID-19 policy. METHODS: From February 20 to April 10, 2023, we included 393 children aged 8 months to less than 3 years who did not receive COVID-19 vaccination and 114 children aged 3 to 6 years who received inactivated COVID-19 vaccines based on the convenience sampling in this cross-sectional study. IgG and IgM antibodies against nucleocapsid (N) and subunit 1 of spike (S1) of SARS-CoV-2 (anti-N/S1) were measured with commercial kits (Shenzhen YHLO Biotech, China). RESULTS: Of the 393 unvaccinated children (1.5 ± 0.6 years; 52.2% boys), 369 (93.9%) were anti-N/S1 IgG positive. Of the 114 vaccinated children (5.3 ± 0.9 years; 48.2% boys), 112 (98.2%) were anti-N/S1 IgG positive. None of the unvaccinated or vaccinated children was anti-N/S1 IgM positive. The median IgG antibody titers in vaccinated children (344.91 AU/mL) were significantly higher than that in unvaccinated children (42.80 AU/mL) (P < 0.0001). The positive rates and titers of anti-N/S1 IgG had no significant difference between boys and girls respectively. CONCLUSION: Vast majority of children were infected with SARS-CoV-2 shortly after ending zero-COVID-19 policy in China. Whether these unvaccinated infected children should receive COVID-19 vaccine merits further investigation.


Assuntos
Anticorpos Antivirais , Vacinas contra COVID-19 , COVID-19 , Imunoglobulina G , SARS-CoV-2 , Humanos , COVID-19/prevenção & controle , COVID-19/imunologia , COVID-19/epidemiologia , China/epidemiologia , Pré-Escolar , Masculino , Feminino , Vacinas contra COVID-19/imunologia , Vacinas contra COVID-19/administração & dosagem , Criança , Anticorpos Antivirais/sangue , SARS-CoV-2/imunologia , Lactente , Estudos Transversais , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Vacinação/estatística & dados numéricos , Glicoproteína da Espícula de Coronavírus/imunologia
2.
Nat Commun ; 15(1): 5139, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38886388

RESUMO

Although it is well documented that mountains tend to exhibit high biodiversity, how geological processes affect the assemblage of montane floras is a matter of ongoing research. Here, we explore landform-specific differences among montane floras based on a dataset comprising 17,576 angiosperm species representing 140 Chinese mountain floras, which we define as the collection of all angiosperm species growing on a specific mountain. Our results show that igneous bedrock (granitic and karst-granitic landforms) is correlated with higher species richness and phylogenetic overdispersion, while the opposite is true for sedimentary bedrock (karst, Danxia, and desert landforms), which is correlated with phylogenetic clustering. Furthermore, we show that landform type was the primary determinant of the assembly of evolutionarily older species within floras, while climate was a greater determinant for younger species. Our study indicates that landform type not only affects montane species richness, but also contributes to the composition of montane floras. To explain the assembly and differentiation of mountain floras, we propose the 'floristic geo-lithology hypothesis', which highlights the role of bedrock and landform processes in montane floristic assembly and provides insights for future research on speciation, migration, and biodiversity in montane regions.


Assuntos
Biodiversidade , Magnoliopsida , Filogenia , China , Magnoliopsida/crescimento & desenvolvimento , Altitude , Fenômenos Geológicos , Ecossistema
3.
J Nanobiotechnology ; 22(1): 339, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38890734

RESUMO

Diabetic kidney disease (DKD), a chronic kidney disease, is characterized by progressive fibrosis caused due to persistent hyperglycemia. The development of fibrosis in DKD determines the patient prognosis, but no particularly effective treatment. Here, small extracellular vesicles derived from mesenchymal stem cells (MSC-sEV) have been used to treat DKD fibrosis. Single-cell RNA sequencing was used to analyze 27,424 cells of the kidney, we have found that a novel fibrosis-associated TGF-ß1+Arg1+ macrophage subpopulation, which expanded and polarized in DKD and was noted to be profibrogenic. Additionally, Actin+Col4a5+ mesangial cells in DKD differentiated into myofibroblasts. Multilineage ligand-receptor and cell-communication analysis showed that fibrosis-associated macrophages activated the TGF-ß1/Smad2/3/YAP signal axis, which promotes mesangial fibrosis-like change and accelerates renal fibrosis niche. Subsequently, the transcriptome sequencing and LC-MS/MS analysis indicated that MSC-sEV intervention could restore the levels of the kinase ubiquitin system in DKD and attenuate renal interstitial fibrosis via delivering CK1δ/ß-TRCP to mediate YAP ubiquitination degradation in mesangial cells. Our findings demonstrate the unique cellular and molecular mechanisms of MSC-sEV in treating the DKD fibrosis niche at a single-cell level and provide a novel therapeutic strategy for renal fibrosis.


Assuntos
Nefropatias Diabéticas , Vesículas Extracelulares , Fibrose , Células-Tronco Mesenquimais , Análise de Célula Única , Transcriptoma , Vesículas Extracelulares/metabolismo , Células-Tronco Mesenquimais/metabolismo , Animais , Camundongos , Nefropatias Diabéticas/metabolismo , Nefropatias Diabéticas/terapia , Masculino , Camundongos Endogâmicos C57BL , Humanos , Macrófagos/metabolismo , Transdução de Sinais , Fator de Crescimento Transformador beta1/metabolismo , Células Mesangiais/metabolismo , Rim/patologia , Rim/metabolismo
4.
Neuron ; 112(9): 1498-1517.e8, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38430912

RESUMO

Recognizing the affective states of social counterparts and responding appropriately fosters successful social interactions. However, little is known about how the affective states are expressed and perceived and how they influence social decisions. Here, we show that male and female mice emit distinct olfactory cues after experiencing distress. These cues activate distinct neural circuits in the piriform cortex (PiC) and evoke sexually dimorphic empathic behaviors in observers. Specifically, the PiC → PrL pathway is activated in female observers, inducing a social preference for the distressed counterpart. Conversely, the PiC → MeA pathway is activated in male observers, evoking excessive self-grooming behaviors. These pathways originate from non-overlapping PiC neuron populations with distinct gene expression signatures regulated by transcription factors and sex hormones. Our study unveils how internal states of social counterparts are processed through sexually dimorphic mechanisms at the molecular, cellular, and circuit levels and offers insights into the neural mechanisms underpinning sex differences in higher brain functions.


Assuntos
Empatia , Caracteres Sexuais , Animais , Masculino , Feminino , Camundongos , Empatia/fisiologia , Córtex Piriforme/fisiologia , Córtex Piriforme/metabolismo , Sinais (Psicologia) , Camundongos Endogâmicos C57BL , Afeto/fisiologia , Neurônios/fisiologia , Neurônios/metabolismo , Comportamento Animal/fisiologia
5.
Curr Biol ; 34(7): 1453-1468.e6, 2024 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-38484733

RESUMO

Itch encompasses both sensory and emotional dimensions, with the two dimensions reciprocally exacerbating each other. However, whether a shared neural circuit mechanism governs both dimensions remains elusive. Here, we report that the anterior insular cortex (AIC) is activated by both histamine-dependent and -independent itch stimuli. The activation of AIC elicits aversive emotion and exacerbates pruritogen-induced itch sensation and aversion. Mechanistically, AIC excitatory neurons project to the GABAergic neurons in the dorsal bed nucleus of the stria terminalis (dBNST). Manipulating the activity of the AIC → dBNST pathway affects both itch sensation and itch-induced aversion. Our study discovers the shared neural circuit (AIC â†’ dBNST pathway) underlying the itch sensation and aversion, highlights the critical role of the AIC as a central hub for the itch processing, and provides a framework to understand the neural mechanisms underlying the sensation and emotion interaction.


Assuntos
Córtex Insular , Sensação , Humanos , Sensação/fisiologia , Neurônios GABAérgicos/metabolismo , Histamina/efeitos adversos , Histamina/metabolismo , Prurido/induzido quimicamente
6.
Plants (Basel) ; 13(2)2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38256828

RESUMO

Liquidambar L. is a significant constituent of the Cenozoic flora in the Northern Hemisphere. Currently, this genus exhibits a discontinuous distribution across Asia and North America, with the center of diversity being in southeastern Asia. This study presents the first occurrence of Liquidambar in the Oligocene of South China. Fossil sweetgum infructescences, associated pollen, and leaves have been found in the Nanning Basin, Guangxi. A new species, Liquidambar nanningensis sp. nov., is described based on the morphological and anatomical characteristics of three-dimensionally preserved infructescences. The Liquidambar fossils from the Nanning Basin show a combination of features indicative of the former genera of Altingiaceae, Altingia, Liquidambar s. str., and Semiliquidambar. The new occurrence expands the taxonomic and morphological diversity of the Paleogene Liquidambar species in South China.

7.
Artigo em Inglês | MEDLINE | ID: mdl-38192150

RESUMO

BACKGROUND: We investigated how reduced successful ablation criteria may be used to evaluate radioiodine remnant ablation in patients with low- and intermediate-differentiated thyroid carcinoma (DTC). METHODS: Overall, 254 low- and intermediate-risk patients with DTC were categorized into three groups (positive, weak, positive, and negative) on the basis of a visual study of thyroid imaging performed before postoperative iodine treatment. Semi-quantitative analysis parameters were incorporated into the positive Tc-99m pertechnetate scanning to further examine the clinical use of thyroid imaging. We investigated the value of successful judgment criteria and the influencing factors of radioiodine ablation. At the same time, the predictive value of thyroglobulin (Tg) for radioiodine treatment and the overall clinical efficacy were assessed. RESULTS: A total of 250 (98.43%) patients were identified as having functional thyroid tissue residue on the Tx-whole-body scan, and 137 (53.94%) patients had positive Tc-99m pertechnetate scans using semi-quantitative analysis. The single Tg standard could not substitute the double standard (χ! !=22.042, p<0.001) for patients with residual thyroid weight by a semiquantitative analysis. However, the semi-quantitative analysis revealed no association between 99mTcO4-thyroid scan and ablation treatment using semi-quantitative analysis; only preablation sTg levels were related with success in the multivariate logistic regression analysis, with a cut-off value of 2.88 ng/mL. The pre-ablation stimulated Tg level was also the primary factor of satisfactory response following follow-up with an optimal cut-off of 6.506 ng/mL. CONCLUSION: Even in low- and intermediate-risk patients with DTC, a single negative Tg standard also requires receiving some restrictions in the evaluation of ablation success and is inadequate. Conventional 99mTcO4 thyroid imaging combined with a quantitative analysis program can improve the clinical practice of single negative Tg standard.

8.
NPJ Regen Med ; 9(1): 3, 2024 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-38218925

RESUMO

Renal interstitial fibrosis (RIF) is a fundamental pathological feature of chronic kidney disease (CKD). However, toxicity and poor renal enrichment of fibrosis inhibitors limit their further applications. In this study, a platform for CKD therapy is developed using superparamagnetic iron oxide nanoparticles (SPION) decorated mesenchymal stem cells derived extracellular vesicles with carboxyl terminus of Hsc70-interacting protein (CHIP) high expression (SPION-EVs) to achieve higher renal-targeting antifibrotic therapeutic effect. SPION-EVs selectively accumulate at the injury renal sites under an external magnetic field. Moreover, SPION-EVs deliver CHIP to induce Smad2/3 degradation in renal tubular cells which alleviates Smad2/3 activation-mediated fibrosis-like changes and collagen deposition. The extracellular vesicle engineering technology provides a potential nanoplatform for RIF therapy through CHIP-mediated Smad2/3 degradation.

9.
Oncol Rep ; 51(2)2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38099408

RESUMO

Gastrointestinal cancer is frequently detected at an advanced stage and has an undesirable prognosis due to the absence of efficient and precise biomarkers and therapeutic targets. Exosomes are small, living­cell­derived vesicles that serve a critical role in facilitating intercellular communication by transporting molecules from donor cells to receiver cells. circular RNAs (circRNAs) are mis­expressed in a variety of diseases, including gastrointestinal cancer, and are promising as diagnostic biomarkers and tumor therapeutic targets for gastrointestinal cancer. The main features of exosomes and circRNAs are discussed in the present review, along with research on the biological function of exosomal circRNAs in the development and progression of gastrointestinal cancer. It also assesses the advantages and disadvantages of implementing these findings in clinical applications.


Assuntos
Exossomos , Neoplasias Gastrointestinais , Humanos , RNA Circular/genética , Neoplasias Gastrointestinais/diagnóstico , Neoplasias Gastrointestinais/genética , Transporte Biológico , Comunicação Celular , Exossomos/genética , Biomarcadores
10.
Adv Sci (Weinh) ; 10(34): e2304068, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37870169

RESUMO

Immune cells can protect against tumor progression by killing cancer cells, while aberrant expression of the immune checkpoint protein PD-L1 (programmed death ligand 1) in cancer cells facilitates tumor immune escape and inhibits anti-tumor immunotherapy. As a serine/threonine kinase, CK2 (casein kinase 2) regulates tumor progression by multiple pathways, while it is still unclear the effect of CK2 on tumor immune escape. Here it is found that ING4 induced PD-L1 autophagic degradation and inhibites non-small cell lung cancer (NSCLC) immune escape by increasing T cell activity. However, clinical analysis suggests that high expression of CK2 correlates with low ING4 protein level in NSCLC. Further analysis shows that CK2 induce ING4-S150 phosphorylation leading to ING4 ubiquitination and degradation by JFK ubiquitin ligase. In contrast, CK2 gene knockout increases ING4 protein stability and T cell activity, subsequently, inhibites NSCLC immune escape. Furthermore, the combined CK2 inhibitor with PD-1 antibody effectively enhances antitumor immunotherapy. These findings provide a novel strategy for cancer immunotherapy.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/terapia , Carcinoma Pulmonar de Células não Pequenas/genética , Neoplasias Pulmonares/genética , Antígeno B7-H1/metabolismo , Caseína Quinase II/uso terapêutico , Imunoterapia , Proteínas de Homeodomínio , Proteínas de Ciclo Celular , Proteínas Supressoras de Tumor/metabolismo , Proteínas Supressoras de Tumor/uso terapêutico
11.
Ann Med ; 55(2): 2249936, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37683195

RESUMO

Objective: To investigate the effect of different bladder filling states on positioning errors in radiotherapy for cervical cancer and obtain the reference range of bladder filling consistency during radiotherapy.Methods: Patients who underwent postoperative radiotherapy for cervical cancer in Nantong Tumor Hospital from October 2018 to December 2019 were selected. According to the bladder filling deviation, they were divided into group A1 (deviation < 20%) and group B1 (deviation ≥ 20%). The bladder filling variations of the two groups were compared with different positioning errors. Group A2 has a positioning error of <0.4 cm, and group B2 has a positioning error of ≥0.4 cm. The reference range of bladder filling consistency during radiotherapy is obtained by analyzing the composition ratio of different positioning errors of bladder filling deviation.Results: This study included 195 patients with cervical cancer. The error of longitudinal and vertical position in group B1 was significantly higher than that in group A1 (0.50 ± 0.34 vs. 0.26 ± 0.22 cm, p < 0.001, and 0.22 ± 0.17 vs. 0.16 ± 0.12 cm, p < 0.001). Compared with group B2, the absolute deviation of bladder filling in group A2 (54.1% ± 54.4% vs. 25.6% ± 22.7%, p < 0.001) was slight. The chi-square test showed significant differences in the proportion of the positioning state of different bladder filling forms (χ2 = 31.006, p < 0.001). In addition, there was a significant difference in the proportion of stability errors in patients with poor stability in different directions (χ2 = 118.551, p < 0.001).Conclusion: In patients with cervical cancer fixed in the supine position, a bladder capacity deviation <20% is easier to achieve excellent positioning with, and it can better control the positioning error of radiotherapy and ensure the positioning accuracy of dose distribution to the target area. It can also achieve good tumor treatment effects. This range can be used as a reference for bladder filling consistency in patients with cervical cancer undergoing radiotherapy.


Assuntos
Neoplasias do Colo do Útero , Feminino , Humanos , Neoplasias do Colo do Útero/radioterapia , Neoplasias do Colo do Útero/cirurgia , Bexiga Urinária/cirurgia , Histerectomia , Valores de Referência
12.
Biomed Pharmacother ; 167: 115527, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37751642

RESUMO

While previous research on cancer biology has focused on genes that code for proteins, in recent years it has been discovered that non-coding RNAs (ncRNAs)play key regulatory roles in cell biological functions. NcRNAs account for more than 95% of human transcripts and are an important entry point for the study of the mechanism of cancer development. An increasing number of studies have demonstrated that ncRNAs can act as tumor suppressor genes or oncogenes to regulate tumor development at the epigenetic level, transcriptional level, as well as post-transcriptional level. Because of the importance of ncRNAs in cancer, most clinical trials have focused on ncRNAs to explore whether ncRNAs can be used as new biomarkers or therapies. In this review, we focus on recent studies of ncRNAs including microRNAs (miRNAs), long ncRNAs (lncRNAs), circle RNAs (circRNAs), PIWI interacting RNAs (piRNAs), and tRNA in different types of cancer and explore the application of these ncRNAs in the development of cancer and the identification of relevant therapeutic targets and tumor biomarkers. Graphical abstract drawn by Fidraw.

13.
Plant Divers ; 45(4): 434-445, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37601538

RESUMO

Quercus is the largest genus within the Fagaceae and has a rich fossil record. Most of the fossil material is attributed to the subgenus Quercus based on leaves, pollen or rarely acorns and nuts. Fossil records of Q. section Cyclobalanopsis characterized by ring-cupped acorns are relatively few and especially those described based on nuts are scant. In this study, we described four new species of Quercus section Cyclobalanopsis based on mummified acorns and nuts: Q. paleodisciformis X.Y. Liu et J.H. Jin sp. nov., Q. paleohui X.Y. Liu et J.H. Jin sp. nov., Q. nanningensis X.Y. Liu et J.H. Jin sp. nov. and Q. yongningensis X.Y. Liu et J.H. Jin sp. nov. These species closely resemble the extant species Q. disciformis, Q. hui, Q. kerrii, and Q. dinghuensis. The occurrence of Q. section Cyclobalanopsis in the Oligocene stratum of Guangxi, South China, suggests that the section has diversified within its extant distribution center since the Oligocene. By combining records from other areas, we propose that the section first appeared in the middle Eocene of East Asia (Sino-Japan), has diversified in situ with a few elements scattering into West Asia and southern Europe since the Oligocene and Pliocene, respectively, and finally became restricted in East Asia since the Pleistocene. This indicates that the section originated and diversified in East Asia, before spreading into West Asia no later than the Oligocene and into southern Europe by the Pliocene. Subsequently it disappeared from South Europe and West Asia due to the appearance of the (summer dry) Mediterranean climate and widespread cooling during the Pleistocene.

14.
iScience ; 26(8): 107313, 2023 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-37554461

RESUMO

Anatomical structure of mummified wood of Cryptocarya (Lauraceae) from the Upper Pleistocene of Maoming, South China and the woods of 15 extant species of Cryptocarya from China and Malaysia were examined. The fossil wood has been convincingly attributed to extant species Cryptocarya chinensis (Hance) Hemsl. This is the first reliable fossil record of Cryptocarya in Asia. The finding combined with the results of Biomod2 species distribution modeling suggest that the range of C. chinensis in the Late Pleistocene in South China and North Vietnam was very restricted due to increased continental aridity and enhanced temperature seasonality in this region. Thus, modern populations of C. chinensis in Maoming can be considered as glacial relicts. The mines (larval tunnels) produced by the larvae of flies from the genus Phytobia Lioy (Agromyzidae, Diptera) were observed in fossil wood under study. These cambial miners have never been reported in Cryptocarya.

15.
Cancer Cell Int ; 23(1): 151, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37525152

RESUMO

BACKGROUND: Exosome, a component of liquid biopsy, loaded protein, DNA, RNA and lipid gradually emerges as biomarker in tumors. However, exosomal circRNAs as biomarker and function mechanism in gastric cancer (GC) are not well understood. METHODS: Differentially expressed circRNAs in GC and healthy people were screened by database. The identification of hsa_circ_000200 was verified by RNase R and sequencing, and the expression of hsa_circ_000200 was evaluated using qRT-PCR. The biological function of hsa_circ_000200 in GC was verified in vitro. Western blot, RIP, RNA fluorescence in situ hybridization, and double luciferase assay were utilized to explore the potential mechanism of hsa_circ_000200. RESULTS: Hsa_circ_000200 up-regulated in GC tissue, serum and serum exosomes. Hsa_circ_000200 in serum exosomes showed better diagnostic ability than that of tissues and serum. Combined with clinicopathological parameters, its level was related to invasion depth, TNM staging, and distal metastasis. Functionally, knockdown of hsa_circ_000200 inhibited GC cells proliferation, migration and invasion in vitro, while its overexpression played the opposite role. Importantly, exosomes with up-regulated hsa_circ_000200 promoted the proliferation and migration of co-cultured GC cells. Mechanistically, hsa_circ_000200 acted as a "ceRNA" for miR-4659a/b-3p to increase HBEGF and TGF-ß/Smad expression, then promoted the development of GC. CONCLUSIONS: Our findings suggest that hsa_circ_000200 promotes the progression of GC through hsa_circ_000200/miR-4659a/b-3p/HBEGF axis and affecting the expression of TGF-ß/Smad. Serum exosomal hsa_circ_000200 may serve as a potential biomarker for GC.

16.
J Cell Biochem ; 124(8): 1145-1154, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37393598

RESUMO

As a master transcription factor, c-Myc plays an important role in promoting tumor immune escape. In addition, PPARγ (peroxisome proliferator-activated receptor γ) regulates cell metabolism, inflammation, and tumor progression, while the effect of PPARγ on c-Myc-mediated tumor immune escape is still unclear. Here we found that cells treated with PPARγ agonist pioglitazone (PIOG) reduced c-Myc protein expression in a PPARγ-dependent manner. qPCR analysis showed that PIOG had no significant effect on c-Myc gene levels. Further analysis showed that PIOG decreased c-Myc protein half-life. Moreover, PIOG increased the binding of c-Myc to PPARγ, and induced c-Myc ubiquitination and degradation. Importantly, c-Myc increased PD-L1 and CD47 immune checkpoint protein expression and promoted tumor immune escape, while PIOG inhibited this event. These findings suggest that PPARγ agonist inhibited c-Myc-mediated tumor immune escape by inducing its ubiquitination and degradation.


Assuntos
Neoplasias Colorretais , Pioglitazona , Tiazolidinedionas , Humanos , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Regulação da Expressão Gênica , Pioglitazona/farmacologia , PPAR gama/agonistas , PPAR gama/metabolismo , Tiazolidinedionas/farmacologia , Evasão Tumoral , Proteínas Proto-Oncogênicas c-myc/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-myc/metabolismo
17.
JHEP Rep ; 5(7): 100746, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37274776

RESUMO

Background & Aims: Non-alcoholic fatty liver disease (NAFLD) affects nearly a quarter of the population with no approved pharmacological therapy. Liver steatosis is a primary characteristic of NAFLD. Recent studies suggest that human umbilical cord mesenchymal stem cell-derived exosomes (MSC-ex) may provide a promising strategy for treating liver injury; however, the role and underlying mechanisms of MSC-ex in steatosis are not fully understood. Methods: Oleic-palmitic acid-treated hepatic cells and high-fat diet (HFD)-induced NAFLD mice were established to observe the effect of MSC-ex. Using non-targeted lipidomics and transcriptome analyses, we analysed the gene pathways positively correlated with MSC-ex. Mass spectrometry and gene knockdown/overexpression analyses were performed to evaluate the effect of calcium/calmodulin-dependent protein kinase 1 (CAMKK1) transferred by MSC-ex on lipid homoeostasis regulation. Results: Here, we demonstrate that MSC-ex promote fatty acid oxidation and reduce lipogenesis in oleic-palmitic acid-treated hepatic cells and HFD-induced NAFLD mice. Non-targeted lipidomics and transcriptome analyses suggested that the effect of MSC-ex on lipid accumulation positively correlated with the phosphorylation of AMP-activated protein kinase. Furthermore, mass spectrometry and gene knockdown/overexpression analyses revealed that MSC-ex-transferred CAMKK1 is responsible for ameliorating lipid accumulation in an AMP-activated protein kinase-dependent manner, which subsequently inhibits SREBP-1C-mediated fatty acid synthesis and enhances peroxisome proliferator-activated receptor alpha (PPARα)-mediated fatty acid oxidation. Conclusions: MSC-ex may prevent HFD-induced NAFLD via CAMKK1-mediated lipid homoeostasis regulation. Impact and Implications: NAFLD includes many conditions, from simple steatosis to non-alcoholic steatohepatitis, which can lead to fibrosis, cirrhosis, and even hepatocellular carcinoma. So far, there is no approved drug for treating liver steatosis of NAFLD. Thus, better therapies are needed to regulate lipid metabolism and prevent the progression from liver steatosis to chronic liver disease. By using a combination of non-targeted lipidomic and transcriptome analyses, we revealed that human umbilical cord mesenchymal stem cell-derived exosomes (MSC-ex) effectively reduced lipid deposition and improved liver function from HFD-induced liver steatosis. Our study highlights the importance of exosomal CAMKK1 from MSC-ex in mediating lipid metabolism regulation via AMPK-mediated PPARα/CPT-1A and SREBP-1C/fatty acid synthase signalling in hepatocytes. These findings are significant in elucidating novel mechanisms related to MSC-ex-based therapies for preventing NAFLD.

18.
iScience ; 26(6): 106867, 2023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-37260748

RESUMO

Fossil genera with similar features to the winged fruits of the living Engelhardia Lesch. ex Blume (e.g., Palaeocarya G. Saporta) have been widely reported in Cenozoic fossil floras of the Northern Hemisphere. However, fossil winged fruits of Engelhardia with detailed anatomical structures have only been found in the upper Eocene of North America. This study reports the first Engelhardia fossil winged fruits with detailed anatomical structures in East Asia from the Miocene Erzitang Formation of Guangxi, South China. The anatomical and morphological features of the new fossils, including the unique structure of secondary septa, clearly distinguish them from other fossil genera and show unambiguously their attribution to the genus Engelhardia. This discovery suggests that Engelhardia had reached its modern distribution during the Miocene and the climate of the Guiping Basin in Guangxi during the Miocene was similar to that of present-day tropical and subtropical regions in Asia.

19.
Quant Imaging Med Surg ; 13(5): 2907-2921, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-37179916

RESUMO

Background: Cone-beam computed tomography (CBCT) is an important tool for patient positioning in radiotherapy due to its outstanding advantages. However, the CBCT registration shows errors due to the limitations of the automatic registration algorithm and the nonuniqueness of manual verification results. The purpose of this study was to verify the feasibility of using the Sphere-Mask Optical Positioning System (S-M_OPS) to improve the registration stability of CBCT through clinical trials. Methods: From November 2021 to February 2022, 28 patients who received intensity-modulated radiotherapy and site verification with CBCT were included in this study. S-M_OPS was used as an independent third-party system to supervise the CBCT registration result in real time. The supervision error was calculated based on the CBCT registration result and using the S-M_OPS registration result as the standard. For the head and neck, patients with a supervision error ≥3 or ≤-3 mm in 1 direction were selected. For the thorax, abdomen, pelvis, or other body parts, patients with a supervision error ≥5 or ≤-5 mm in 1 direction were selected. Then, re-registration was performed for all patients (selected and unselected). The registration errors of CBCT and S-M_OPS were calculated based on the re-registration results as the standard. Results: For selected patients with large supervision errors, CBCT registration errors (mean ± standard deviation) in the latitudinal (LAT; left/right), vertical (VRT; superior/inferior), and longitudinal (LNG; anterior/posterior) directions were 0.90±3.20, -1.70±0.98, and 7.30±2.14 mm, respectively. The S-M_OPS registration errors were 0.40±0.14, 0.32±0.66, and 0.24±1.12 mm in the LAT, VRT, and LNG directions, respectively. For all patients, CBCT registration errors in the LAT, VRT, and LNG directions were 0.39±2.69, -0.82±1.47, and 2.39±2.93 mm, respectively. The S-M_OPS registration errors were -0.25±1.33, 0.55±1.27, and 0.36±1.34 mm for all patients in the LAT, VRT, and LNG directions, respectively. Conclusions: This study shows that S-M_OPS registration offers comparable accuracy to CBCT for daily registration. S-M_OPS, as an independent third-party tool, can prevent large errors in CBCT registration, thereby improving the accuracy and stability of CBCT registration.

20.
Eur J Pharmacol ; 950: 175749, 2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37105516

RESUMO

Blockade of PD-1/PD-L1 immune checkpoint could be an effective antitumor strategy for multiple types of cancer, but it is low response rate for colorectal cancer patients with unclear mechanism. Here we found that PPARγ agonist pioglitazone could reduce PD-L1 protein levels without effect on its gene expression. Further analysis showed that pioglitazone induced PD-L1 autophagic degradation in a PPARγ-dependent manner. Pioglitazone promoted PD-L1 translocation to lysosome by immunofluorescence analysis, which was associated with the increased binding of PPARγ to PD-L1. Moreover the combined pioglitazone with PD-1 antibody enhanced colorectal tumor immunotherapy, which was involved in reduced PD-L1 levels and increased CD8+ T cells. These findings suggest that PPARγ agonist could induce PD-L1 autophagic degradation resulting in increased colorectal tumor immunotherapy.


Assuntos
Linfócitos T CD8-Positivos , Neoplasias Colorretais , Humanos , Antígeno B7-H1/metabolismo , Pioglitazona/farmacologia , PPAR gama , Receptor de Morte Celular Programada 1/metabolismo , Imunoterapia/métodos , Neoplasias Colorretais/tratamento farmacológico
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