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1.
Anal Chem ; 96(24): 10084-10091, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38836421

RESUMO

Due to the potential off-tumor signal leakage and limited biomarker content, there is an urgent need for stimulus-responsive and amplification-based tumor molecular imaging strategies. Therefore, two tetrahedral framework DNA (tFNA-Hs), tFNA-H1AP, and tFNA-H2, were rationally engineered to form a polymeric tFNA network, termed an intelligent DNA network, in an AND-gated manner. The intelligent DNA network was designed for tumor-specific molecular imaging by leveraging the elevated expression of apurinic/apyrimidinic endonuclease 1 (APE1) in tumor cytoplasm instead of normal cells and the high expression of miRNA-21 in tumor cytoplasm. The activation of tFNA-H1AP can be achieved through specific recognition and cleavage by APE1, targeting the apurinic/apyrimidinic site (AP site) modified within the stem region of hairpin 1 (H1AP). Subsequently, miRNA-21 facilitates the hybridization of activated H1AP on tFNA-H1AP with hairpin 2 (H2) on tFNA-H2, triggering a catalytic hairpin assembly (CHA) reaction that opens the H1AP at the vertices of tFNA-H1AP to bind with H2 at the vertices of tFNA-H2 and generate fluorescence signals. Upon completion of hybridization, miRNA-21 is released, initiating the subsequent cycle of the CHA reaction. The AND-gated intelligent DNA network can achieve specific tumor molecular imaging in vivo and also enables risk stratification of neuroblastoma patients.


Assuntos
DNA Liase (Sítios Apurínicos ou Apirimidínicos) , DNA , MicroRNAs , Humanos , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/metabolismo , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/química , MicroRNAs/metabolismo , MicroRNAs/análise , DNA/química , DNA/metabolismo , Imagem Molecular/métodos , Animais , Imagem Óptica
2.
Ann Surg ; 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-38073601

RESUMO

OBJECTIVE: To compare the surgical outcomes of robotic-assisted proctosigmoidectomy (RAP) and laparoscopic-assisted Soave pull-through (LAP) for children with Hirschsprung's disease (HD). SUMMARY BACKGROUND DATA: LAP and RAP have been developed for minimally invasive pull-through of HD, but the clinical benefits of robotic-assisted versus laparoscopic-assisted approaches have yet to be proven in a multicenter prospective study. METHODS: This study was a prospective multicenter clinical trial conducted on children with rectosigmoid/descending HD from July 2015 to June 2022, with registration in the Chinese Clinical Trial Registry (ChiCTR2000035220). The primary outcome was the medium-term functional outcomes in children aged ≥4 years based on bowel functional scores, which were assessed and compared between LAP and RAP. RESULTS: A total of 328 consecutive patients (RAP=165, LAP=163) were approached who were considered eligible for elective minimally invasive endorectal pull-through, and 219 patients aged ≥4 years of age completed follow-up (RAP=109, LAP=110). The transanal dissection length and anal traction time were significantly shorter in RAP than those in LAP (0.30 cm vs. 3.70 cm, P <0.001; 45 min vs. 62 min, P <0.001). The RAP group had significantly lower urinary retention rate (0% vs. 5.52%, P=0.006), while other short-term results between two groups were not significantly different. The medium-term overall BFS scores were comparable between two groups; however, among the subgroup of children aged ≤ 3 months at surgery, the RAP group had better anal canal resting pressure at one year postoperatively and amounted to better annual POFC scores at 4-7 years old postoperatively (all P <0.05). CONCLUSIONS: RAP and LAP should have similar medium-term bowel functional outcomes in HD children, but RAP may be associated with a slight functional benefit in infants operated on below age 3 months, requiring further investigation in larger case cohorts.

3.
Mod Pathol ; 36(11): 100303, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37580017

RESUMO

Fumarate hydratase (FH)-deficient renal cell carcinoma (RCC) is a rare and distinct subtype of renal cancer caused by FH gene mutations. FH negativity and s-2-succinocysteine (2SC) positivity on immunohistochemistry can be used to screen for FH-deficient RCC, but their sensitivity and specificity are not perfect. The expression of AKR1B10, an aldo-keto reductase that catalyzes cofactor-dependent oxidation-reduction reactions, in RCC is unclear. We compared AKR1B10, 2SC, and FH as diagnostic biomarkers for FH-deficient RCC. We included genetically confirmed FH-deficient RCCs (n = 58), genetically confirmed TFE3 translocation RCCs (TFE3-tRCC) (n = 83), clear cell RCCs (n = 188), chromophobe RCCs (n = 128), and papillary RCCs (pRCC) (n = 97). AKR1B10, 2SC, and FH were informative diagnostic markers. AKR1B10 had 100% sensitivity and 91.4% specificity for FH-deficient RCC. The nonspecificity of AKR1B10 was shown in 26.5% of TFE3-tRCCs and 21.6% of pRCCs. 2SC showed 100% sensitivity and 88.9% specificity. However, nonspecificity for 2SC was evident in multiple RCCs, including pRCC, TFE3-tRCC, clear cell RCCs, and chromophobe RCCs. FH was 100% specific but 84.5% sensitive. AKR1B10 served as a highly sensitive and specific diagnostic biomarker. Our findings suggest the value of combining AKR1B10 and 2SC to screen for FH-deficient RCC. AKR1B10+/2SC+/FH- cases can be diagnosed as FH-deficient RCC. Patients with AKR1B10+/2SC+/FH+ are highly suspicious of FH-deficient RCC and should be referred for FH genetic tests.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Humanos , Carcinoma de Células Renais/patologia , Fumarato Hidratase/genética , Fumarato Hidratase/metabolismo , Neoplasias Renais/patologia , Fatores de Transcrição , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos , Aldo-Ceto Redutases
4.
Surg Endosc ; 37(5): 3540-3547, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36602550

RESUMO

BACKGROUND: Robotic-assisted Kasai portoenterostomy (RAKPE) has been utilized to treat biliary atresia (BA). However, RAKPE is not widely performed and its efficacy remains unknown. We summarized the experience of RAKPE for BA and determined its efficacy. MATERIALS AND METHODS: We retrospectively analyzed 25 consecutive infants with non-syndromic type III BA who received RAKPE in our center from January 2020 to July 2021. RAKPE is a three-arm setup and four-trocar operation. Bipolar coagulation was used to dissect the small blood vessels at the hepatic portal. The fibrous cone was shallowly transected with bending electric scissors, followed by gelatin sponge compression to staunch the hemorrhage. Finally, a wide anastomosis was accurately constructed. Demographics and outcomes were recorded. RESULTS: The mean operative time was 211.64 ± 18.93 min. No conversion to laparotomy or intraoperative complications occurred. The mean estimated blood loss was 7.64 ± 2.43 mL. Enteral feeding was resumed after 3.44 ± 1.23 days. All patients achieved bile excretion postoperatively, and dark green bile-stained stools were passed 1.50 days (range 1.00-3.00 days) after surgery. The average postoperative length of hospital stay was 10.32 ± 2.59 days. The jaundice clearance (JC) rate was 76.00% within 6 months after surgery and the incidence of cholangitis was 48.00% within 1 year following surgery. The survival with native liver (SNL) rate was 80.00% at 1 year and 66.67% at 2 years. CONCLUSION: RAKPE can be regarded as a treatment option for patients with BA due to the good outcomes reported. However, long-term studies comparing open or laparoscopic approaches are needed.


Assuntos
Atresia Biliar , Laparoscopia , Procedimentos Cirúrgicos Robóticos , Lactente , Humanos , Atresia Biliar/cirurgia , Portoenterostomia Hepática , Estudos Retrospectivos , Procedimentos Cirúrgicos Robóticos/efeitos adversos , Laparoscopia/efeitos adversos , Resultado do Tratamento
5.
Surg Endosc ; 37(1): 31-47, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35913517

RESUMO

BACKGROUND: Most commonly, cyst excision and Roux-en-Y hepaticojejunostomy reconstruction are the optimal treatment for choledochal cysts (CC). Robotic surgery (RS) is being conducted with increasing frequency to treat CC. It is unclear whether RS can overcome the limitations of laparoscopic surgery (LS) and improve the prognosis of patients. In terms of efficacy, evidence concerning which minimally invasive surgery is preferred is, however, sparse. Our objective is to further compare the efficacy of RS and LS in children with CC and draw a useful clinical conclusion. METHODS: Studies meeting inclusion criteria were identified from a series of databases, consisting of PubMed, Embase, Scopus, Web of Science, the Cochrane Library and their reference list of articles up to May 2022. Eligible articles comprised at least five objects that were younger than 18 years of age and the language was limited to English. Two authors independently evaluated selected studies and extracted data for analysis. RESULTS: Forty studies were selected for analysis, with thirty-six reporting data on LS and eight containing data on RS. The pooled conversion rate and pooled postoperative complication rate of RS were lower than those of LS, but none of them was statistically significant. Moreover, comparisons of the following detailed postoperative complication rates were not statistically significant, such as intestinal obstruction or ileus, anastomotic bleeding, anastomotic or bile leakage, and anastomotic stenosis. However, the intraoperative blood loss and the postoperative hospital stay in RS group were significantly lower than those in LS group. CONCLUSIONS: RS is a safe and feasible option for children with CC. Further studies with more cases, long-term efficacy and health economics analysis are needed to confirm whether RS is more advantageous.


Assuntos
Cisto do Colédoco , Obstrução Intestinal , Laparoscopia , Procedimentos Cirúrgicos Robóticos , Criança , Humanos , Anastomose em-Y de Roux , Cisto do Colédoco/cirurgia , Obstrução Intestinal/cirurgia , Laparoscopia/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Estudos Retrospectivos , Procedimentos Cirúrgicos Robóticos/efeitos adversos , Resultado do Tratamento
6.
BMC Surg ; 23(1): 365, 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-38049799

RESUMO

PURPOSE: There are only a few case reports of laparoscopic lateral duodenojejunostomy (LLDJ) in children with Wilkie's syndrome, also known as superior mesenteric artery compression syndrome (SMAS). We aimed to describe our laparoscopic technique and evaluate its outcomes for SMAS in children. METHODS: From January 2013 to May 2021, SMAS children who received LLDJ were included. The procedure was carried out utilizing the four-trocar technique. The elevation of the transverse colon allows good exposure of the dilated and bulging second and third sections of the duodenum. Using a linear stapler, we established a lateral anastomosis connecting the proximal jejunum with the third part of the duodenum. Following that, a running suture was used to intracorporeally close the common enterotomy. Clinical data on patients was collected for analysis. The demographics, diagnostic findings, and postoperative outcomes were analyzed retrospectively. RESULTS: We retrospectively analyzed 9 SMAS patients (6 females and 3 males) who underwent LLDJ, aged between 7 and 17 years old. The mean operative time was 118.4 ± 16.5 min and the mean estimated blood loss was 5.6 ± 1.4 ml. There were no conversion, intraoperative complications or immediate postoperative complications. The mean postoperative hospital stay was 6.8 ± 1.9 days and the mean follow-up time was 5.4 ± 3.0 years. During follow-up, seven patients (77.8%) experienced complete recovery of symptoms prior to surgery. One patient (11.1%) still had mild vomiting, which resolved with medication. Another patient (11.1%) developed psychological-induced nausea, which significantly improved after treatment with education, training and diet management. CONCLUSIONS: LLDJ represents a feasible and safe treatment option for SMAS in well-selected children. Further evaluation with more cases and case-control studies is required for the real benefits.


Assuntos
Laparoscopia , Síndrome da Artéria Mesentérica Superior , Masculino , Feminino , Humanos , Criança , Adolescente , Estudos Retrospectivos , Artéria Mesentérica Superior/cirurgia , Síndrome da Artéria Mesentérica Superior/cirurgia , Síndrome da Artéria Mesentérica Superior/diagnóstico , Laparoscopia/métodos , Anastomose Cirúrgica/métodos
7.
BMC Med ; 20(1): 292, 2022 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-35941608

RESUMO

BACKGROUND: Although cholesterol metabolism is a common pathway for the development of antitumor drugs, there are no specific targets and drugs for clinical use. Here, based on our previous study of sterol O-acyltransferase 1 (SOAT1) in hepatocelluar carcinoma, we sought to screen an effective targeted drug for precise treatment of hepatocelluar carcinoma and, from the perspective of cholesterol metabolism, clarify the relationship between cholesterol regulation and tumorigenesis and development. METHODS: In this study, we developed a virtual screening integrated affinity screening technology for target protein drug screening. A series of in vitro and in vivo experiments were used for drug activity verification. Multi-omics analysis and flow cytometry analysis were used to explore antitumor mechanisms. Comparative analysis of proteome and transcriptome combined with survival follow-up information of patients reveals the clinical therapeutic potential of screened drugs. RESULTS: We screened three compounds, nilotinib, ABT-737, and evacetrapib, that exhibited optimal binding with SOAT1. In particular, nilotinib displayed a high affinity for SOAT1 protein and significantly inhibited tumor activity both in vitro and in vivo. Multi-omics analysis and flow cytometry analysis indicated that SOAT1-targeting compounds reprogrammed the cholesterol metabolism in tumors and enhanced CD8+ T cells and neutrophils to suppress tumor growth. CONCLUSIONS: Taken together, we reported several high-affinity SOAT1 ligands and demonstrated their clinical potential in the precision therapy of liver cancer, and also reveal the potential antitumor mechanism of SOAT1-targeting compounds.


Assuntos
Linfócitos T CD8-Positivos , Carcinoma , Colesterol/metabolismo , Humanos , Esterol O-Aciltransferase/química , Esterol O-Aciltransferase/metabolismo
8.
Anal Biochem ; 658: 114922, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36162447

RESUMO

A dual isothermal amplification assay with dual fluorescence signal detection strategy, named dual isothermal amplification all-in-one approach, was developed for rapid, one-step, highly sensitive quantification of plasma circulating MYCN copy number of neuroblastoma (NB). The developed strategy consisted of rolling circle amplification (RCA) and loop-mediated isothermal amplification (LAMP) on a real-time PCR system using highly specific probe, molecular beacon (MB), as detection probe. The developed strategy possessing a broad linear dynamic range of 10 aM to 1 pM for both target gene (MYCN) and reference gene (NAGK). The ratio of the MYCN copy number to NAGK copy number (M/N ratio) was detected by the developed approach in cell lines, NB tumor tissues, hepatoblastoma tumor tissues and Wilms' tumor tissues, to which the M/N ratios were consistent with previous reports. In particular, the M/N ratio in NB clinical tissue specimens and NB plasma specimens detected with the developed approach were in keeping with the standard RT-PCR approach. More importantly, the M/N ratio in NB tissue samples and corresponding plasma samples of NB patients were consistent with each other with a correlation coefficient of 0.9690, indicating that plasma circulating MYCN is a promising indicator for the risk classification of NB.


Assuntos
Neuroblastoma , Proteínas Oncogênicas , Humanos , Proteína Proto-Oncogênica N-Myc/genética , Proteína Proto-Oncogênica N-Myc/metabolismo , Proteínas Oncogênicas/genética , Proteínas Oncogênicas/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Neuroblastoma/patologia , Reação em Cadeia da Polimerase em Tempo Real , Sondas Moleculares , Amplificação de Genes
9.
PLoS Pathog ; 15(4): e1007680, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30943264

RESUMO

Mediator of IRF3 activation (MITA, also known as STING and ERIS) is an essential adaptor protein for cytoplasmic DNA-triggered signaling and involved in innate immune responses, autoimmunity and tumorigenesis. The activity of MITA is critically regulated by ubiquitination and deubiquitination. Here, we report that USP49 interacts with and deubiquitinates MITA after HSV-1 infection, thereby turning down cellular antiviral responses. Knockdown or knockout of USP49 potentiated HSV-1-, cytoplasmic DNA- or cGAMP-induced production of type I interferons (IFNs) and proinflammatory cytokines and impairs HSV-1 replication. Consistently, Usp49-/- mice exhibit resistance to lethal HSV-1 infection and attenuated HSV-1 replication compared to Usp49+/+ mice. Mechanistically, USP49 removes K63-linked ubiquitin chains from MITA after HSV-1 infection which inhibits the aggregation of MITA and the subsequent recruitment of TBK1 to the signaling complex. These findings suggest a critical role of USP49 in terminating innate antiviral responses and provide insights into the complex regulatory mechanisms of MITA activation.


Assuntos
Herpes Simples/prevenção & controle , Imunidade Inata/imunologia , Lisina/metabolismo , Proteínas de Membrana/metabolismo , Ubiquitina Tiolesterase/metabolismo , Animais , Antivirais , Células HEK293 , Herpes Simples/imunologia , Herpes Simples/virologia , Herpesvirus Humano 1 , Humanos , Lisina/química , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Transdução de Sinais , Células THP-1 , Ubiquitina Tiolesterase/genética , Ubiquitinação , Replicação Viral
10.
J Immunol ; 202(8): 2397-2406, 2019 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-30814308

RESUMO

Mediator of IRF3 activation ([MITA] also known as STING) is a direct sensor of cyclic dinucleotide and critically mediates cytoplasmic DNA--triggered innate immune signaling. The activity of MITA is extensively regulated by ubiquitination and deubiquitination. In this study, we report that USP20 interacts with and removes K48-linked ubiquitin chains from MITA after HSV-1 infection, thereby stabilizing MITA and promoting cellular antiviral responses. Deletion of USP20 accelerates HSV-1-induced degradation of MITA and impairs phosphorylation of IRF3 and IκBα as well as subsequent induction of type I IFNs and proinflammatory cytokines after HSV-1 infection or cytoplasmic DNA challenge. Consistently, Usp20 -/- mice produce decreased type I IFNs and proinflammatory cytokines, exhibit increased susceptibility to lethal HSV-1 infection, and aggravated HSV-1 replication compared with Usp20 +/+ mice. In addition, complement of MITA into Usp20 -/- cells fully restores HSV-1-triggered signaling and inhibits HSV-1 infection. These findings suggest a crucial role of USP20 in maintaining the stability of MITA and promoting innate antiviral signaling.


Assuntos
Endopeptidases/imunologia , Herpes Simples/imunologia , Herpesvirus Humano 1/imunologia , Proteínas de Membrana/imunologia , Proteólise , Ubiquitinação/imunologia , Animais , Endopeptidases/genética , Herpes Simples/genética , Imunidade Inata , Interferon Tipo I/genética , Interferon Tipo I/imunologia , Proteínas de Membrana/genética , Camundongos , Camundongos Knockout , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Ubiquitina Tiolesterase , Ubiquitinação/genética
11.
Fish Shellfish Immunol ; 100: 126-136, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32142872

RESUMO

Astragalus polysaccharides (APS) have been widely used as immunopotentiators in aquaculture, however, the best way of their administration remains to be explored. In the present study, APS liposome (APSL) was prepared by film dispersion-ultrasonic method. The optimal conditions of APSL preparation were determined by response surface methodology, with a ratio of 10:1 (w/w) for soybean lecithin to APS and 8:1 (w/w) for soybean lecithin to cholesterol, and an ultrasound time of 15 min, which produced an encapsulation efficiency of 73.88 ± 0.88% of APSL. In vivo feeding experiments in large yellow croaker showed that both APS and APSL could enhance the contents of serum total protein (TP) and albumin (ALB), activities of serum non-specific immune enzymes such as acid phosphatase (ACP), alkaline phosphatase (AKP), and lysozyme (LZM), and phagocytic activity of head kidney macrophages. Meanwhile, they both increased the activities of serum antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT) and reduced the content of final lipid peroxidation product malondialdehyde (MDA) in serum, thus exhibiting the antioxidant effects. In vitro experiments on primary head kidney macrophages (PKM) showed that both APS and APSL inhibited ROS production, but obviously enhanced NO production and phagocytic activity of PKM. Furthermore, expression levels of pro-inflammatory cytokines (IL-1ß, IL-6, IL-8, and TNF-α), IFN-γ, and iNOS in PKM were significantly up-regulated after APS and APSL treatments, but no expression change of IFN-h was observed. Taken together, our results showed that both APS and APSL could improve several immune parameters and antioxidant ability of large yellow croaker either in vivo or in vitro, and the efficacy of APSL was markedly better than APS. These findings therefore indicated that the immunomodulatory and antioxidant activities of APS could be enhanced after encapsulated with liposome, and APSL may represent a potential drug delivery system of APS for development of immunoenhancers in aquaculture.


Assuntos
Antioxidantes/farmacologia , Astrágalo/química , Fatores Imunológicos/farmacologia , Perciformes/imunologia , Extratos Vegetais/farmacologia , Animais , Aquicultura , Proteínas Sanguíneas/análise , Rim Cefálico/citologia , Rim Cefálico/imunologia , Lipossomos/química , Macrófagos/imunologia , Fagocitose , Albumina Sérica/análise
12.
Sensors (Basel) ; 20(14)2020 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-32708473

RESUMO

As one of the important components of electrocardiogram (ECG) signals, QRS signal represents the basic characteristics of ECG signals. The detection of QRS waves is also an essential step for ECG signal analysis. In order to further meet the clinical needs for the accuracy and real-time detection of QRS waves, a simple, fast, reliable, and hardware-friendly algorithm for real-time QRS detection is proposed. The exponential transform (ET) and proportional-derivative (PD) control-based adaptive threshold are designed to detect QRS-complex. The proposed ET can effectively narrow the magnitude difference of QRS peaks, and the PD control-based method can adaptively adjust the current threshold for QRS detection according to thresholds of previous two windows and predefined minimal threshold. The ECG signals from MIT-BIH databases are used to evaluate the performance of the proposed algorithm. The overall sensitivity, positive predictivity, and accuracy for QRS detection are 99.90%, 99.92%, and 99.82%, respectively. It is also implemented on Altera Cyclone V 5CSEMA5F31C6 Field Programmable Gate Array (FPGA). The time consumed for a 30-min ECG record is approximately 1.3 s. It indicates that the proposed algorithm can be used for wearable heart rate monitoring and automatic ECG analysis.


Assuntos
Algoritmos , Eletrocardiografia , Processamento de Sinais Assistido por Computador , Bases de Dados Factuais , Humanos
13.
Soft Matter ; 15(30): 6107-6115, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31282902

RESUMO

CO2-monitoring plays an important role in medicine, environmental sciences, and food industries. Here, a new CO2-responsive hydrogel film was fabricated from branched polyethyleneimine (BPEI) and partially oxidized dextran (PO-Dex) via layer-by-layer (LBL) assembly, based on the in situ Schiff base reaction between the two polymers. The swelling behaviours of the films were studied using Fabry-Perot fringes on their reflection spectra. Like ordinary hydrogels, the BPEI/PO-Dex films swell in water. In addition, they swell to a larger degree when CO2 is introduced, due to the reaction between CO2 and the amino groups in BPEI. The CO2-induced swelling can be reported by the shift of the Fabry-Perot fringes on their reflection spectra; therefore, the BPEI/PO-Dex film can be used as an optical sensor for dissolved CO2. In the new sensor, the BPEI/PO-Dex film acts as a CO2-sensing material and Fabry-Perot cavity simultaneously. The introduction of ordered structure is no longer required. The response of the sensor to CO2 is linear and reversible. Unlike other hydrogel-based sensors that suffer from a slow response, the new sensor can respond to CO2 quickly, making it applicable for real-time, continuous monitoring of CO2 levels in solution.

15.
Nanomedicine ; 14(7): 2475-2483, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-28552648

RESUMO

Herein, we report on development of a two-dimensional nanomaterial graphene oxide (GO)-based T1 magnetic resonance imaging (MRI) contrast agent (CA) for in vitro and in vivo labeling of human mesenchymal stem cells (hMSCs). The CA was synthesized by PEGylation of ultrasmall GO, followed by conjugation with a chelating agent DOTA and then gadolinium(III) to form GO-DOTA-Gd complexes. Thus-prepared GO-DOTA-Gd complexes exhibited significantly improved T1 relaxivity, and the r1 value was 14.2 mM-1s-1 at 11.7 T, approximately three times higher than Magnevist, a commercially available CA. hMSCs can be effectively labeled by GO-DOTA-Gd, leading to remarkably enhanced cellular MRI effect without obvious adverse effects on proliferation and differentiation of hMSCs. More importantly, in vivo experiment revealed that intracranial detection of 5×105 hMSCs labeled with GO-DOTA-Gd is achieved. The current work demonstrates the feasibility of the GO-based T1 MRI CA for stem cell labeling, which may find potential applications in regenerative medicine.


Assuntos
Meios de Contraste/química , Grafite/química , Compostos Heterocíclicos/química , Imageamento por Ressonância Magnética/métodos , Células-Tronco Mesenquimais/citologia , Compostos Organometálicos/química , Animais , Proliferação de Células , Rastreamento de Células , Células Cultivadas , Humanos , Técnicas In Vitro , Masculino , Células-Tronco Mesenquimais/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus
16.
Proc Natl Acad Sci U S A ; 112(36): 11324-9, 2015 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-26305951

RESUMO

Host pathogen-recognition receptors detect nucleic acid from invading viruses and initiate a series of signaling pathways that lead to the production of type I interferons (IFNs) and proinflammatory cytokines. Here, we found that a viral infection-induced deubiquitinase (DUB), ubiquitin-specific protease 25 (USP25) was required for host defense against RNA and DNA viruses. The activation of transcription factors IRF3 and NF-κB was impaired and the production of type I IFNs and proinflammatory cytokines was inhibited in Usp25-/- cells compared with the wild-type counterparts after RNA or DNA viruses infection. Consistently, USP25 deficient mice were more susceptible to H5N1 or HSV-1 infection compared with the wild-type mice. USP25 was associated with TRAF3 and TRAF6 after infection by RNA or DNA viruses and protected virus-induced proteasome-dependent or independent degradation of TRAF3 and TRAF6, respectively. Moreover, reconstitution of TRAF3 and TRAF6 into Usp25-/- MEFs restored virus-triggered production of type I IFNs and proinflammatory cytokines. Our findings thus reveal a previously uncovered positive feedback regulation of innate immune responses against RNA and DNA viruses by USP25.


Assuntos
Imunidade Inata/imunologia , Fator 3 Associado a Receptor de TNF/imunologia , Fator 6 Associado a Receptor de TNF/imunologia , Ubiquitina Tiolesterase/imunologia , Viroses/imunologia , Vírus/imunologia , Animais , Células Cultivadas , Citocinas/genética , Citocinas/imunologia , Citocinas/metabolismo , Embrião de Mamíferos/citologia , Feminino , Fibroblastos/imunologia , Fibroblastos/metabolismo , Fibroblastos/virologia , Expressão Gênica/imunologia , Células HEK293 , Interações Hospedeiro-Patógeno/imunologia , Humanos , Imunidade Inata/genética , Immunoblotting , Mediadores da Inflamação/imunologia , Mediadores da Inflamação/metabolismo , Interferon Tipo I/genética , Interferon Tipo I/imunologia , Interferon Tipo I/metabolismo , Masculino , Camundongos Knockout , NF-kappa B/imunologia , NF-kappa B/metabolismo , Complexo de Endopeptidases do Proteassoma/imunologia , Complexo de Endopeptidases do Proteassoma/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator 3 Associado a Receptor de TNF/metabolismo , Fator 6 Associado a Receptor de TNF/metabolismo , Ubiquitina Tiolesterase/genética , Ubiquitina Tiolesterase/metabolismo , Viroses/genética , Viroses/virologia
19.
J Am Chem Soc ; 136(44): 15684-93, 2014 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-25340966

RESUMO

Enhanced near-field at noble metal nanoparticle surfaces due to localized surface plasmon resonance (LSPR) has been researched in fields ranging from biomedical to photoelectrical applications. However, it is rarely explored on nonmetallic nanomaterials discovered in recent years, which can also support LSPR by doping-induced free charge carriers, let alone the investigation of an intricate system involving both. Here we construct a dual plasmonic hybrid nanosystem Au-Cu9S5 with well controlled interfaces to study the coupling effect of LSPR originating from the collective electron and hole oscillations. Cu9S5 LSPR is enhanced by 50% in the presence of Au, and the simulation results confirm the coupling effect and the enhanced local field as well as the optical power absorption on Cu9S5 surface. This enhanced optical absorption cross section, high photothermal transduction efficiency (37%), large light penetration depth at 1064 nm, excellent X-ray attenuation ability, and low cytotoxicity enable Au-Cu9S5 hybrids for robust photothermal therapy in the second near-infrared (NIR) window with low nanomaterial dose and laser flux, making them potential theranostic nanomaterials with X-ray CT imaging capability. This study will benefit future design and optimization of photoabsorbers and photothermal nanoheaters utilizing surface plasmon resonance enhancement phenomena for a broad range of applications.

20.
Heliyon ; 10(10): e31579, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38831805

RESUMO

In the swiftly evolving business landscape, digital transformation (DT) has emerged as a crucial strategy for firms to gain a competitive edge. Despite the abundance of literature on DT in firms, there remains a dearth of empirical research that defines and analyzes crucial antecedents of small and medium-sized enterprises' (SMEs) DT from an internal perspective. To fill this research gap, this study examines the correlation between organizational agility and digital capability in cultivating SMEs' DT while also evaluating top management support as a moderating variable through the lens of internal factors of SMEs. The results indicate that both organizational agility and digital capability have a positive impact on SMEs' DT, with organizational agility significantly influencing digital capability. Furthermore, the findings highlight that digital capability serves as a mediator between organizational agility and SMEs' DT. In addition, top management support plays a moderating role in these relationships to a certain extent. Additionally, we explicate the concept of digital capabilities from the perspective of dynamic capability. Our study contributes to an enhanced understanding of the effect of organizational agility and digital capability on SMEs' DT, as well as the role of top management support. We provide recommendations for managers to enhance organizational agility and suggest that SMEs should improve their digital thinking to better perceive digital technology changes, enhance digital operation capabilities, and better integrate digital resources.

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