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Global climate change has led to shifts in the distribution ranges of many terrestrial species, promoting their migration from lower altitudes or latitudes to higher ones. Meanwhile, successful invaders have developed genetic adaptations enabling the colonization of new environments. Over the past 40â years, Rattus tanezumi (RT) has expanded into northern China (Northwest and North China) from its southern origins. We studied the cold adaptation of RT and its potential for northward expansion by comparing it with sympatric Rattus norvegicus (RN), which is well adapted to cold regions. Through population genomic analysis, we revealed that the invading RT rats have split into three distinct populations: the North, Northwest, and Tibetan populations. The first two populations exhibited high genetic diversity, while the latter population showed remarkably low genetic diversity. These rats have developed various genetic adaptations to cold, arid, hypoxic, and high-UV conditions. Cold acclimation tests revealed divergent thermoregulation between RT and RN. Specifically, RT exhibited higher brown adipose tissue activity and metabolic rates than did RN. Transcriptome analysis highlighted changes in genes regulating triglyceride catabolic processes in RT, including Apoa1 and Apoa4, which were upregulated, under selection and associated with local adaptation. In contrast, RN showed changes in carbohydrate metabolism genes. Despite the cold adaptation of RT, we observed genotypic and phenotypic constraints that may limit its ability to cope with severe low temperatures farther north. Consequently, it is less likely that RT rats will invade and overlap with RN rats in farther northern regions.
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Aclimatação , Temperatura Baixa , Animais , Ratos , Aclimatação/genética , China , Fenótipo , Variação Genética , Adaptação Fisiológica/genética , Regulação da Temperatura Corporal/genética , Mudança ClimáticaRESUMO
Oxygen-mediated triplet-triplet annihilation upconversion (TTA-UC) quenching limits the application of such organic upconversion materials. Here, we report that the photooxidation of organic amines is an effective and versatile strategy to suppress oxygen-mediated upconversion quenching in both organic solvents and aqueous solutions. The strategy is based on the dual role of organic amines in photooxidation, i.e., as singlet oxygen scavengers and electron donors. Under photoexcitation, the photosensitizer sensitizes oxygen to produce singlet oxygen for the oxidation of alkylamine, reducing the oxygen concentration. However, photoinduced electron transfer among photosensitizers, organic amines, and oxygen leads to the production of superoxide anions that suppress TTA-UC. To observe oxygen-tolerating TTA-UC, we find that alkyl secondary amines can balance the production of singlet oxygen and superoxide anions. We then utilize polyethyleneimine (PEI) to synthesize amphiphilic polymers to encapsulate TTA-UC pairs for the formation of water-dispersible, ultrasmall, and multicolor-emitting TTA-UC nanoparticles.
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Labeling the genome and envelope of a virus with multicolor quantum dots (QDs) simultaneously enables real-time monitoring of viral uncoating and genome release, contributing to our understanding of virus infection mechanisms. However, current labeling techniques require genetic modification, which alters the virus's composition and infectivity. To address this, we utilized the CRISPR/Cas13 system and a bioorthogonal metabolic method to label the Japanese encephalitis virus (JEV) genome and envelopes with different-colored QDs in situ. This technique allows one-step two-color labeling of the viral envelope and intraviral genome with QDs harnessing virus infection. In combination with single-virus tracking, we visualized JEV uncoating and genome release in real time near the endoplasmic reticulum of live cells. This labeling strategy allows for real-time visualization of uncoating and genome release at the single-virus level, and it is expected to advance the study of other viral infection mechanisms.
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Pontos Quânticos , Viroses , Vírus , Humanos , Envelope Viral/metabolismo , Proteínas do Envelope ViralRESUMO
The anti-Stokes shift represents the capacity of photon upconversion to convert low-energy photons to high-energy photons. Although triplet exciton-mediated photon upconversion presents outstanding performance in solar energy harvesting, photoredox catalysis, stereoscopic 3D printing, and disease therapeutics, the interfacial multistep triplet exciton transfer leads to exciton energy loss to suppress the anti-Stokes shift. Here, we report near infrared-II (NIR-II) excitable triplet exciton-mediated photon upconversion using a hybrid photosensitizer consisting of lead sulfide quantum dots (PbS QDs) and new surface ligands of thiophene-substituted diketopyrrolopyrrole (Th-DPP). Under 1064 nm excitation, this photon upconversion revealed a record-corrected upconversion efficiency of 0.37% (normalized to 100%), with the anti-Stokes shift (1.07 eV) approaching the theoretical limit (1.17 eV). The observation of this unexpected result is due to our discovery of the presence of a weak interaction between the sulfur atom on Th-DPP and Pb2+ on the PbS QDs surface, facilitating electronic coupling between PbS QDs and Th-DPP, such that the realization of triplet exciton transfer efficiency is close to 100% even when the energy gap is as small as 0.04 eV. With this premise, this photon upconversion as a photocatalyst enables the production of standing organic gel via photopolymerization under 1064 nm illumination, displaying NIR-II photon-driven photoredox catalysis. This research not only establishes the foundation for enhancing the performance of NIR-II excitable photonic upconversion but also promotes its development in photonics and photoredox catalysis.
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The diagnosis of disease biomarkers is crucial for the identification, monitoring, and prognostic assessment of malignant disease. However, biological samples with autofluorescence, complex components, and heterogeneity pose major challenges to reliable biosensing. Here, we report the self-assembly of natural proteins and the triplet-triplet annihilation upconversion (TTA-UC) pair to form upconverted protein clusters (â¼8.2 ± 1.1 nm), which were further assembled into photon upconversion supramolecular assemblies (PUSA). This PUSA exhibited unique features, including a small size (â¼44.1 ± 4.1 nm), oxygen tolerance, superior biocompatibility, and easy storage via lyophilization, all of which are long sought after for photon upconversion materials. Further, we have revealed that the steric hindrance of the annihilator suppresses the stacking of the annihilator in PUSA, which is vital for maintaining the water dispersibility and enhancing the upconversion performance of PUSA. In conjunction with sarcosine oxidase, this near infrared (NIR)-excitable PUSA nanoprobe could perform background-free biosensing of urinary sarcosine, which is a common biomarker for prostatic carcinoma (PCa). More importantly, this nanoprobe not only allows for qualitative identification of urinary samples from PCa patients by the unaided eye under NIR-light-emitting diode (LED) illumination but also quantifies the concentration of urinary sarcosine. These remarkable findings have propelled photon upconversion materials to a new evolutionary stage and expedited the progress of upconversion biosensing in clinical diagnostics.
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Técnicas Biossensoriais , Fótons , Humanos , Sarcosina/urina , Sarcosina/química , Sarcosina Oxidase/química , Proteínas/análise , Proteínas/químicaRESUMO
Cardiac fibrosis is a detrimental pathological process, which constitutes the key factor for adverse cardiac structural remodeling leading to heart failure and other critical conditions. Circular RNAs (circRNAs) have emerged as important regulators of various cardiovascular diseases. It is known that several circRNAs regulate gene expression and pathological processes by binding miRNAs. In this study we investigated whether a novel circRNA, named circNSD1, and miR-429-3p formed an axis that controls cardiac fibrosis. We established a mouse model of myocardial infarction (MI) for in vivo studies and a cellular model of cardiac fibrogenesis in primary cultured mouse cardiac fibroblasts treated with TGF-ß1. We showed that miR-429-3p was markedly downregulated in the cardiac fibrosis models. Through gain- and loss-of-function studies we confirmed miR-429-3p as a negative regulator of cardiac fibrosis. In searching for the upstream regulator of miR-429-3p, we identified circNSD1 that we subsequently demonstrated as an endogenous sponge of miR-429-3p. In MI mice, knockdown of circNSD1 alleviated cardiac fibrosis. Moreover, silence of human circNSD1 suppressed the proliferation and collagen production in human cardiac fibroblasts in vitro. We revealed that circNSD1 directly bound miR-429-3p, thereby upregulating SULF1 expression and activating the Wnt/ß-catenin pathway. Collectively, circNSD1 may be a novel target for the treatment of cardiac fibrosis and associated cardiac disease.
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BACKGROUND: High-dose dual therapy (HDDT) is an emerging and promising therapeutic regime for Helicobacter pylori (H. pylori) eradication. However, the pharmacokinetics of the components of HDDT, amoxicillin and proton pump inhibitor, are likely to be affected by body size. In this study, we aimed to find out the impact of body size on the efficacy of HDDT. METHODS: We collected the medical data of 385 treatment-naive patients infected with H. pylori who received HDDT (esomeprazole 20 mg and amoxicillin 750 mg four times daily) for 14 days from July 2020 to December 2021. The associations among the eradication efficacy, adverse events, and variables (sex, age, height, body weight, body mass index (BMI), body surface area (BSA), smoking, drinking, etc.) were analyzed respectively in our study. Among these factors, continuous variables were classified into categorical variables using the cut-off values which were calculated by receiver operating characteristic analysis. RESULTS: The eradication rate of HDDT was 89.9%. There were 55 (14.3%) patients who occurred adverse events during the treatment. Patients with height <170.5 cm, body weight <60.5 kg, BMI <20.55 kg/m2 , BSA <1.69 m2 had a higher eradication rate (92.1% vs. 84.0%, 93.1% vs. 86.8%, 96.0% vs. 87.8%, 93.4% vs. 84.8%, all p < .05). The multivariate analysis showed that BSA ≥1.69 m2 (OR 2.53, 95% CI: 1.28-4.99, p = .007) was the only independent predictor of eradication failure. CONCLUSION: HDDT could achieve better eradication efficacy in patients with small BSA. Clinicians should be aware of the impact of BSA on the H. pylori eradication rate and pay more attention to patients with large BSA.
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Infecções por Helicobacter , Helicobacter pylori , Humanos , Antibacterianos/uso terapêutico , Infecções por Helicobacter/tratamento farmacológico , Quimioterapia Combinada , Amoxicilina/uso terapêutico , Inibidores da Bomba de Prótons/uso terapêutico , Tamanho Corporal , Peso Corporal , Resultado do Tratamento , Claritromicina/uso terapêuticoRESUMO
Non-healing diabetic wounds (DW) are a serious clinical problem that remained poorly understood. We recently found that topical application of growth differentiation factor 11 (GDF11) accelerated skin wound healing in both Type 1 DM (T1DM) and genetically engineered Type 2 diabetic db/db (T2DM) mice. In the present study, we elucidated the cellular and molecular mechanisms underlying the action of GDF11 on healing of small skin wound. Single round-shape full-thickness wound of 5-mm diameter with muscle and bone exposed was made on mouse dorsum using a sterile punch biopsy 7 days following the onset of DM. Recombinant human GDF11 (rGDF11, 50 ng/mL, 10 µL) was topically applied onto the wound area twice a day until epidermal closure (maximum 14 days). Digital images of wound were obtained once a day from D0 to D14 post-wounding. We showed that topical application of GDF11 accelerated the healing of full-thickness skin wounds in both type 1 and type 2 diabetic mice, even after GDF8 (a muscle growth factor) had been silenced. At the cellular level, GDF11 significantly facilitated neovascularization to enhance regeneration of skin tissues by stimulating mobilization, migration and homing of endothelial progenitor cells (EPCs) to the wounded area. At the molecular level, GDF11 greatly increased HIF-1É expression to enhance the activities of VEGF and SDF-1É, thereby neovascularization. We found that endogenous GDF11 level was robustly decreased in skin tissue of diabetic wounds. The specific antibody against GDF11 or silence of GDF11 by siRNA in healthy mice mimicked the non-healing property of diabetic wound. Thus, we demonstrate that GDF11 promotes diabetic wound healing via stimulating endothelial progenitor cells mobilization and neovascularization mediated by HIF-1É-VEGF/SDF-1É pathway. Our results support the potential of GDF11 as a therapeutic agent for non-healing DW.
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Diabetes Mellitus Experimental , Células Progenitoras Endoteliais , Fatores de Diferenciação de Crescimento , Cicatrização , Animais , Humanos , Camundongos , Proteínas Morfogenéticas Ósseas/metabolismo , Quimiocina CXCL12/efeitos dos fármacos , Quimiocina CXCL12/metabolismo , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Células Progenitoras Endoteliais/metabolismo , Células Progenitoras Endoteliais/patologia , Fatores de Diferenciação de Crescimento/uso terapêutico , Fatores de Diferenciação de Crescimento/metabolismo , Neovascularização Fisiológica , Fator A de Crescimento do Endotélio Vascular/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/metabolismo , Cicatrização/efeitos dos fármacos , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/uso terapêutico , Subunidade alfa do Fator 1 Induzível por Hipóxia/efeitos dos fármacos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismoRESUMO
Clusters are considered to become increasingly significant for elaborating the nanocrystal's formation mechanism. However, capturing the clusters with high chemical potential is challenging because of the lack of effective strategies. In this work, the key role of ligand-solvent interaction has been revealed for the stabilization of clusters in silver telluride synthesis. The Flory interaction coefficient that comprehensively regards the temperature and dispersion, polarity, and hydrogen bonding of the solvent has been used to evaluate the ligand-solvent interaction and thus assist in the design of synthetic systems. Small silver telluride clusters have been successfully captured, and the composition of the smallest cluster is determined as Ag7Te8(SCy)2 (SCy represents the ligand). This work provides new insights into the design of cluster/nanocrystal synthesis systems and paves the way to revealing the mechanism of precursor-cluster-nanocrystal conversion.
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Triplet-triplet annihilation upconversion (TTA-UC) with near-infrared (NIR) photosensitizers is highly desirable for a variety of emerging applications. However, the development of NIR-to-blue TTA-UC with a large anti-Stokes shift is extremely challenging because of the energy loss during the intersystem crossing (ISC). Here, we develop the first NIR-absorbing B,N-heteroarene-based sensitizer (BNS) with multi-resonance thermally activated delayed fluorescence (MR-TADF) characters to achieve efficient NIR-to-blue TTA-UC. The small energy gap between the singlet and triplet excited states (0.14â eV) of BNS suppresses the ISC energy loss, and its long-delayed fluorescence lifetime (115â µs) contributes to efficient triplet energy transfer. As a result, the largest anti-Stokes shift (1.03â eV) among all heavy-atom-free NIR-activatable TTA-UC systems is obtained with a high TTA-UC quantum yield of 2.9 % (upper limit 50 %).
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Citoesqueleto , Fármacos Fotossensibilizantes , Fármacos Fotossensibilizantes/farmacologia , Transferência de Energia , Fluorescência , VibraçãoRESUMO
Skin-derived stem cells (SDSCs) are a class of adult stem cells (ASCs) that have the ability to self-renew and differentiate. The regulation mechanisms involved in the differentiation of SDSCs are a hot topic. In this paper, we explore the link between the transcriptional regulator yes-associated protein (YAP) and the fate of porcine SDSCs (pSDSCs). We found that lysophosphatidylcholine (LPC) activates YAP, promotes pSDSCs pluripotency, and counteracts transdifferentiation of pSDSCs into porcine primordial germ cell-like cells (pPGCLCs). YAP promotes the pluripotent state of pSDSCs by maintaining the high expression of the pluripotency genes Oct4 and Sox2. The overexpression of YAP prevented the differentiation of pSDSCs, and the depletion of YAP by small interfering RNA (siRNAs) suppressed the self-renewal of pSDSCs. In addition, we found that YAP regulates the fate of pSDSCs through a mechanism related to the Wnt/ß-catenin signaling pathway. When an activator of the Wnt/ß-catenin signaling pathway, CHIR99021, was added to pSDSCs overexpressing YAP, the ability of pSDSCs to differentiate was partially restored. Conversely, when XAV939, an inhibitor of the Wnt/ß-catenin signaling pathway, was added to YAP knockdown pSDSCs a higher self-renewal ability resulted. Taken together, our results suggested that YAP and the Wnt/ß-catenin signaling pathway interact to regulate the fate of pSDSCs.
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Células-Tronco , Via de Sinalização Wnt , Proteínas de Sinalização YAP , beta Catenina , Animais , Diferenciação Celular , Proliferação de Células , Células-Tronco/metabolismo , Suínos , Proteínas de Sinalização YAP/metabolismo , beta Catenina/metabolismoRESUMO
Myocardial ischemia-reperfusion (I/R) injury is a pathological process characterized by cardiomyocyte apoptosis, which leads to cardiac dysfunction. Increasing evidence shows that abnormal expression of long noncoding RNAs (lncRNAs) plays a crucial role in cardiovascular diseases. In this study we investigated the role of lncRNAs in myocardial I/R injury. Myocardial I/R injury was induced in mice by ligating left anterior descending coronary artery for 45 min followed by reperfusion for 24 h. We showed that lncRNA KnowTID_00006395, termed lncRNA-6395 was significantly upregulated in the infarct area of mouse hearts following I/R injury as well as in H2O2-treated neonatal mouse ventricular cardiomyocytes (NMVCs). Overexpression of lncRNA-6395 led to cell apoptosis and the expression change of apoptosis-related proteins in NMVCs, whereas knockdown of lncRNA-6395 attenuated H2O2-induced cell apoptosis. LncRNA-6395 knockout mice (lncRNA-6395+/-) displayed improved cardiac function, decreased plasma LDH activity and infarct size following I/R injury. We demonstrated that lncRNA-6395 directly bound to p53, and increased the abundance of p53 protein through inhibiting ubiquitination-mediated p53 degradation and thereby facilitated p53 translocation to the nucleus. More importantly, overexpression of p53 canceled the inhibitory effects of lncRNA-6395 knockdown on cardiomyocyte apoptosis, whereas knockdown of p53 counteracted the apoptotic effects of lncRNA-6395 in cardiomyocytes. Taken together, lncRNA-6395 as an endogenous pro-apoptotic factor, regulates cardiomyocyte apoptosis and myocardial I/R injury by inhibiting degradation and promoting sub-cellular translocation of p53.
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Traumatismo por Reperfusão Miocárdica , RNA Longo não Codificante , Animais , Apoptose , Proteínas Reguladoras de Apoptose/metabolismo , Proteínas Reguladoras de Apoptose/farmacologia , Peróxido de Hidrogênio/farmacologia , Infarto/patologia , Camundongos , Camundongos Knockout , Traumatismo por Reperfusão Miocárdica/metabolismo , Miócitos Cardíacos , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismoRESUMO
BACKGROUND: Ingestion of fish bones leading to gastric perforation and inducing abscess formation in the caudate lobe of the liver is very rare. CASE PRESENTATION: A 67-year-old man presented to our hospital with a 2-day history of subxiphoid pain. There were no specific symptoms other than pain. Laboratory tests showed only an increase in the number and percentage of neutrophils. Contrast-enhanced Computerized tomography (CT) of the abdomen showed two linear dense opacities in the gastric cardia, one of which penetrated the stomach and was adjacent to the caudate lobe of the liver, with inflammatory changes in the caudate lobe. We finally diagnosed his condition as a caudate lobe abscess secondary to intestinal perforation caused by a fishbone based on the history and imaging findings. The patient underwent 3D laparoscopic partial caudate lobectomy, incision and drainage of the liver abscess, and fishbone removal. The procedure was successful and we removed the fishbone from the liver. The patient was discharged on the 9th postoperative day without other complications. CONCLUSIONS: Liver abscess caused by foreign bodies requires multidisciplinary treatment. Especially when located in the caudate lobe, we must detect and remove the cause of the abscess as early as possible. Foreign bodies that perforate the gastrointestinal tract can penetrate to the liver and cause abscess formation, as in this case. When exploring the etiology of liver abscesses, we should investigate the general condition, including the whole gastrointestinal tract.
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Corpos Estranhos , Migração de Corpo Estranho , Laparoscopia , Abscesso Hepático , Idoso , Animais , Corpos Estranhos/complicações , Corpos Estranhos/diagnóstico por imagem , Corpos Estranhos/cirurgia , Migração de Corpo Estranho/complicações , Migração de Corpo Estranho/diagnóstico por imagem , Migração de Corpo Estranho/cirurgia , Humanos , Abscesso Hepático/diagnóstico por imagem , Abscesso Hepático/etiologia , Abscesso Hepático/cirurgia , MasculinoRESUMO
The present study was aimed to investigate the effects of circRNA-0028171 on the apoptosis of vascular endothelial cells induced by arsenic trioxide (As2O3). Human umbilical vein endothelial cells (HUVECs) were treated with 0-15 µmol/L As2O3 for 24 h. Then, cellular viability was measured by MTT assay. The expression levels of circRNA-0028171, Bcl-2 and Bax mRNA were detected by real-time quantitative PCR. Bcl-2/Bax protein ratio was detected by Western blot. Whether circRNA-0028171 was involved in the regulation of HUVECs by As2O3 was investigated by transfection with overexpression plasmid of circRNA-0028171 and siRNA. The results showed that compared with the control group, As2O3 group showed decreased cellular viability, reduced Bcl-2/Bax mRNA and protein ratios, and significantly lower expression of circRNA-0028171. Overexpression of circRNA-0028171 inhibited apoptosis of HUVECs induced by As2O3. Knockdown of circRNA-0028171 by siRNA promoted As2O3-induced apoptosis in HUVECs. These results suggest that circRNA-0028171 is involved in the vascular endothelial cell apoptosis induced by As2O3.
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Apoptose , RNA Circular , Humanos , Trióxido de Arsênio/metabolismo , Trióxido de Arsênio/farmacologia , Proteína X Associada a bcl-2/metabolismo , RNA Interferente Pequeno/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , RNA Mensageiro/metabolismoRESUMO
Ag2Te is one of the most promising semiconductors with a narrow band gap and low toxicity; however, it remains a challenge to tune the emission of Ag2Te quantum dots (QDs) precisely and continuously in a wide range. Herein, Ag2Te QDs emitting from 950 to 2100 nm have been synthesized via trialkylphosphine-controlled growth. Trialkylphosphine has been found to induce the dissolution of small-sized Ag2Te QDs due to its stronger ability to coordinate to the Ag ion than that of 1-octanethiol, predicated by the density functional theory. By controlling this dissolution effect, the monomer supply kinetics can be regulated, achieving precise size control of Ag2Te QDs. This synthetic strategy results in state-of-the-art silver-based QDs with emission tunability. Only by taking advantage of such an ultrawide emission has the sizing curve of Ag2Te been obtained. Moreover, the absolute photoluminescence quantum yield of Ag2Te QDs can reach 12.0% due to their well-passivated Ag-enriched surface with a density of 5.0 ligands/nm2, facilitating noninvasive in vivo fluorescence imaging. The high brightness in the long-wavelength near-infrared (NIR) region makes the cerebral vasculature and the tiny vessel with a width of only 60 µm clearly discriminable. This work reveals a nonclassical growth mechanism of Ag2Te QDs, providing new insight into precisely controlling the size and corresponding photoluminescence properties of semiconductor nanocrystals. The ultrasmall, low-toxicity, emission-tunable, and bright NIR-II Ag2Te QDs synthesized in this work offer a tremendous promise for multicolor and deep-tissue in vivo fluorescence imaging.
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BACKGROUND: Positron emission tomography (PET) imaging is a non-invasive method to visualize and quantify the tumor microenvironment. This study aimed to explore the feasibility of 18F-AIF-NOTA-E[PEG4-c(RGDfk)]2 (denoted as 18F-RGD) PET quantitative parameters to distinguish the angiogenesis in colorectal cancer (CRC) mice which has different metastatic potential. METHODS: Twenty LoVo and twenty LS174T of CRC liver metastases animal models were established by implantation of human CRC cell lines via intrasplenic injection. Radiotracer-based micro-PET imaging of animal model was performed and the uptake of 18F-RGD tracer in the tumor tissues was quantified as tumor-to-liver maximum or mean standardized uptake value (SUVmax or SUVmean) ratio. Pearson correlation was used to analyze the relationship between radioactive parameters and tumor markers. RESULTS: The SUVmax and SUVmean ratios of LoVo model were significantly higher than those of LS174T in both liver metastasis and primary tumor lesions (P < 0.05). A significant difference was observed in both vascular endothelial growth factor (VEGF) and Ki67 expressions between LoVo and LS174T primary tumors (P < 0.05). The tumor-to-liver SUVmax or SUVmean ratio of 18F-RGD showed a moderate correlation with VEGF expression (r = 0.5700, P = 0.001 and r = 0.6657, P < 0.001, respectively), but the SUVmean ration showed a weak correlation with Ki67 expression (r = 0.3706, P < 0.05). The areas under the receiver operating characteristic (ROC) curves of 18F-RGD SUVmean ratio, SUVmax ratio for differentiating LoVo from LS174T tumor were 0.801 and 0.759, respectively. CONCLUSIONS: The tumor-to-liver SUVmean ratio of 18F-RGD was a promising image parameter for the process of monitoring tumor angiogenesis in CRC xenograft mice model.
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Neoplasias Colorretais , Neoplasias Hepáticas , Animais , Neoplasias Colorretais/diagnóstico por imagem , Fluordesoxiglucose F18 , Antígeno Ki-67 , Neoplasias Hepáticas/diagnóstico por imagem , Camundongos , Neovascularização Patológica/diagnóstico por imagem , Oligopeptídeos , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos , Microambiente Tumoral , Fator A de Crescimento do Endotélio VascularRESUMO
BACKGROUND: Positron emission tomography (PET) imaging is a non-invasive functional imaging method used to reflect tumor spatial information, and to provide biological characteristics of tumor progression. The aim of this study was to focus on the application of 18F-fluoromisonidazole (FMISO) PET quantitative parameter of maximum standardized uptake value (SUVmax) ratio to detect the liver metastatic potential of human colorectal cancer (CRC) in mice. METHODS: Colorectal liver metastases (CRLM) xenograft models were established by injecting tumor cells (LoVo, HT29 and HCT116) into spleen of mice, tumor-bearing xenograft models were established by subcutaneously injecting tumor cells in the right left flank of mice. Wound healing assays were performed to examine the ability of cell migration in vitro. 18F-FMISO uptake in CRC cell lines was measured by cellular uptake assay. 18F-FMISO-based micro-PET imaging of CRLM and tumor-bearing mice was performed and quantified by tumor-to-liver SUVmax ratio. The correlation between the 18F-FMISO SUVmax ratio, liver metastases number, hypoxia-induced factor 1α (HIF-1α) and serum starvation-induced glucose transporter 1 (GLUT-1) was evaluated using Pearson correlation analysis. RESULTS: Compared with HT29 and HCT116, LoVo-CRLM mice had significantly higher liver metastases ratio and shorter median survival time. LoVo cells exhibited stronger migration capacity and higher radiotracer uptake compared with HT29 and HCT116 in in vitro. Moreover, 18F-FMISO SUVmax ratio was significantly higher in both LoVo-CRLM model and LoVo-bearing tumor model compared to models established using HT29 and HCT116. In addition, Pearson correlation analysis revealed a significant correlation between 18F-FMISO SUVmax ratio of CRLM mice and number of liver metastases larger than 0.5â¯cm, as well as between 18F-FMISO SUVmax ratio and HIF-1α or GLUT-1 expression in tumor-bearing tissues. CONCLUSIONS: 18F-FMISO parameter of SUVmax ratio may provide useful tumor biological information in mice with CRLM, thus allowing for better prediction of CRLM and yielding useful radioactive markers for predicting liver metastasis potential in CRC.
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Neoplasias Colorretais/patologia , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/secundário , Misonidazol/análogos & derivados , Tomografia por Emissão de Pósitrons/métodos , Intensificação de Imagem Radiográfica , Animais , Modelos Animais de Doenças , Feminino , Humanos , Camundongos , Invasividade Neoplásica/patologia , Distribuição Aleatória , Sensibilidade e Especificidade , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
The new sesquiterpene dimers commiphoroids A-D (1-4) were isolated from Resina Commiphora, and their structures were assigned by spectroscopic methods and X-ray diffraction analysis. Compounds 1 and 2 are stereoisomers of putative [2 + 4]-cycloaddition reactions, and 3 is a trinorsesquiterpene dimer containing a 6/6/5/6/6/6 hexacyclic framework, while 4 possesses a 8-oxabicyclo[3.2.1]oct-6-ene skeletal core. Plausible biosynthetic pathways for 1-4 are proposed. Biochemical studies show that compound 1 promotes ca. 60% expression of keratinocyte-specific markers in adipose-derived stem cells at 10 µM.
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Tecido Adiposo/citologia , Diferenciação Celular/efeitos dos fármacos , Commiphora/química , Dimerização , Sesquiterpenos/química , Sesquiterpenos/farmacologia , Células-Tronco/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Humanos , Células-Tronco/citologiaRESUMO
BACKGROUND: Positron emission tomography (PET) is a noninvasive method to characterize different metabolic activities of tumors, providing information for staging, prognosis, and therapeutic response of patients with cancer. The aim of this study was to evaluate the feasibility of 18F-fludeoxyglucose (18F-FDG) and 3'-deoxy-3'-18F-fluorothymidine (18F-FLT) PET in predicting tumor biological characteristics of colorectal cancer liver metastasis. METHODS: The uptake rate of 18F-FDG and 18F-FLT in SW480 and SW620 cells was measured via an in vitro cell uptake assay. The region of interest was drawn over the tumor and liver to calculate the maximum standardized uptake value ratio (tumor/liver) from PET images in liver metastasis model. The correlation between tracer uptake in liver metastases and VEGF, Ki67 and CD44 expression was evaluated by linear regression. RESULTS: Compared to SW620 tumor-bearing mice, SW480 tumor-bearing mice presented a higher rate of liver metastases. The uptake rate of 18F-FDG in SW480 and SW620 cells was 6.07%⯱â¯1.19% and 2.82%⯱â¯0.15%, respectively (tâ¯=â¯4.69, Pâ¯=â¯0.04); that of 18F-FLT was 24.81%⯱â¯0.45% and 15.57%⯱â¯0.66%, respectively (tâ¯=â¯19.99, Pâ¯<â¯0.001). Micro-PET scan showed that all parameters of FLT were significantly higher in SW480 tumors than those in SW620 tumors. A moderate relationship was detected between metastases in the liver and 18F-FLT uptake in primary tumors (râ¯=â¯0.73, Pâ¯=â¯0.0019). 18F-FLT uptake was also positively correlated with the expression of CD44 in liver metastases (râ¯=â¯0.81, Pâ¯=â¯0.0049). CONCLUSIONS: The uptake of 18F-FLT in metastatic tumor reflects different biological behaviors of colon cancer cells. 18F-FLT can be used to evaluate the metastatic potential of colorectal cancer in nude mice.
Assuntos
Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/secundário , Neoplasias Colorretais/patologia , Didesoxinucleosídeos/administração & dosagem , Fluordesoxiglucose F18/administração & dosagem , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/secundário , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos/administração & dosagem , Adenocarcinoma/metabolismo , Animais , Linhagem Celular Tumoral , Estudos de Viabilidade , Humanos , Receptores de Hialuronatos/metabolismo , Imuno-Histoquímica , Antígeno Ki-67/metabolismo , Modelos Lineares , Neoplasias Hepáticas/metabolismo , Camundongos Nus , Valor Preditivo dos Testes , Fatores de Tempo , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
Activation of Na(+)/H(+) exchanger 1 (NHE1) by lipopolysaccharide (LPS) via Ca(2+)/calpain is responsible in vascular smooth muscle cell (VSMC) apoptosis and to the process of atherosclerosis. Probucol is a lipid-lowering drug which has an anti-atherosclerosis effect. The mechanism remains poorly understood. Here we hypothesized that probucol via inhibition of NHE1 in VSMCs attenuates LPS-accelerated atherosclerosis and promotes plaque stability. Our results revealed that treatment of VSMCs with LPS increased the NHE1 activity in a time-dependent manner, associated with the increased Ca(2+)i. Probucol inhibited the LPS-induced increase of NHE1 activity in a dose-dependent manner in VSMCs for 24-hour co-incubation, as well as the change of Ca(2+)i. In addition, LPS enhanced the calpain activity. Both probucol and calcium chelation of Ca(2+) abolished the LPS-induced increase of calpain activity. Treatment of VSMCs with LPS reduced the expression of Bcl-2 without altering the mRNA level. Probucol inhibited the LPS-reduced expression of Bcl-2 protein in VSMCs. Animal studies indicated administration of probucol suppressed LPS-accelerated apoptosis, atherosclerosis and plaque instability in Apoe(-/-) mice. In conclusion, probucol via inhibition of NHE1 attenuates atherosclerosis lesion growth and promotes plaque stability.