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1.
Biomolecules ; 14(5)2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38785998

RESUMO

Small extracellular vesicles (sEVs) have emerged as promising therapeutic agents and drug delivery vehicles. Targeted modification of sEVs and their contents using genetic modification strategies is one of the most popular methods. This study investigated the effects of p53 fusion with arrestin domain-containing protein 1 (ARRDC1) and CD63 on the generation of sEVs, p53 loading efficiency, and therapeutic efficacy. Overexpression of either ARRDC1-p53 (ARP) or CD63-p53 (CDP) significantly elevated p53 mRNA and protein levels. The incorporation of ARRDC1 and CD63 significantly enhanced HEK293T-sEV biogenesis, evidenced by significant increases in sEV-associated proteins TSG101 and LAMP1, resulting in a boost in sEV production. Importantly, fusion with ARRDC1 or CD63 substantially increased the efficiency of loading both p53 fusion proteins and its mRNA into sEVs. sEVs equipped with ARP or CDP significantly enhanced the enrichment of p53 fusion proteins and mRNA in p53-null H1299 cells, resulting in a marked increase in apoptosis and a reduction in cell proliferation, with ARP-sEVs demonstrating greater effectiveness than CDP-sEVs. These findings underscore the enhanced functionality of ARRDC1- and CD63-modified sEVs, emphasizing the potential of genetic modifications in sEV-based therapies for targeted cancer treatment.


Assuntos
Apoptose , Vesículas Extracelulares , Tetraspanina 30 , Proteína Supressora de Tumor p53 , Humanos , Tetraspanina 30/metabolismo , Tetraspanina 30/genética , Vesículas Extracelulares/metabolismo , Vesículas Extracelulares/genética , Proteína Supressora de Tumor p53/metabolismo , Proteína Supressora de Tumor p53/genética , Células HEK293 , Linhagem Celular Tumoral , Proliferação de Células , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Complexos Endossomais de Distribuição Requeridos para Transporte/genética , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/genética , RNA Mensageiro/metabolismo , RNA Mensageiro/genética , Proteína 1 de Membrana Associada ao Lisossomo
2.
Cardiovasc Toxicol ; 24(5): 481-498, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38647950

RESUMO

The hearts of subjects with diabetes are vulnerable to ischemia-reperfusion injury (IRI). In contrast, experimentally rodent hearts have been shown to be more resistant to IRI at the very early stages of diabetes induction than the heart of the non-diabetic control mice, and the mechanism is largely unclear. Ferroptosis has recently been shown to play an important role in myocardial IRI including that in diabetes, while the specific mechanisms are still unclear. Non-diabetic control (NC) and streptozotocin-induced diabetic (DM) mice were treated with the antioxidant N-acetylcysteine (NAC) in drinking water for 4 week starting at 1 week after diabetes induction. Mice were subjected to myocardial IRI induced by occluding the coronary artery for 30 min followed by 2 h of reperfusion, subsequently at 1, 2, and 5 week of diabetes induction. The post-ischemic myocardial infarct size in the DM mice was smaller than that in NC mice at 1 week of diabetes but greater than that in the NC mice at 2 and 5 week of diabetes, which were associated with a significant increase of ferroptosis at 2 and 5 week but a significant reduction of ferroptosis at 1 week of diabetes. NAC significantly attenuated post-ischemic ferroptosis as well as oxidative stress and reduced infarct size at 2 and 5 week of diabetes. Application of erastin, a ferroptosis inducer, reversed the cardioprotective effects of NAC. It is concluded that increased oxidative stress and ferroptosis are the major factors attributable to the increased vulnerability to myocardial IRI in diabetes and that attenuation of ferroptosis represents a major mechanism whereby NAC confers cardioprotection against myocardial IRI in diabetes.


Assuntos
Acetilcisteína , Antioxidantes , Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 1 , Ferroptose , Camundongos Endogâmicos C57BL , Traumatismo por Reperfusão Miocárdica , Animais , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Traumatismo por Reperfusão Miocárdica/patologia , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Acetilcisteína/farmacologia , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/complicações , Masculino , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 1/metabolismo , Antioxidantes/farmacologia , Ferroptose/efeitos dos fármacos , Infarto do Miocárdio/prevenção & controle , Infarto do Miocárdio/patologia , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/fisiopatologia , Infarto do Miocárdio/tratamento farmacológico , Fatores de Tempo , Miocárdio/patologia , Miocárdio/metabolismo , Camundongos , Estresse Oxidativo/efeitos dos fármacos
3.
Front Oncol ; 14: 1337186, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38515574

RESUMO

Background: Multi-parametric magnetic resonance imaging (MP-MRI) may provide comprehensive information for graded diagnosis of bladder cancer (BCa). Nevertheless, existing methods ignore the complex correlation between these MRI sequences, failing to provide adequate information. Therefore, the main objective of this study is to enhance feature fusion and extract comprehensive features from MP-MRI using deep learning methods to achieve an accurate diagnosis of BCa grading. Methods: In this study, a self-attention-based MP-MRI feature fusion framework (SMMF) is proposed to enhance the performance of the model by extracting and fusing features of both T2-weighted imaging (T2WI) and dynamic contrast-enhanced imaging (DCE) sequences. A new multiscale attention (MA) model is designed to embed into the neural network (CNN) end to further extract rich features from T2WI and DCE. Finally, a self-attention feature fusion strategy (SAFF) was used to effectively capture and fuse the common and complementary features of patients' MP-MRIs. Results: In a clinically collected sample of 138 BCa patients, the SMMF network demonstrated superior performance compared to the existing deep learning-based bladder cancer grading model, with accuracy, F1 value, and AUC values of 0.9488, 0.9426, and 0.9459, respectively. Conclusion: Our proposed SMMF framework combined with MP-MRI information can accurately predict the pathological grading of BCa and can better assist physicians in diagnosing BCa.

4.
J Prosthet Dent ; 131(5): 904.e1-904.e10, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38472073

RESUMO

STATEMENT OF PROBLEM: Implant placement in the mandibular molar sites plays a crucial role in the restoration of edentulous mandibles. However, the evaluation of bone quantity before implant surgery using cone beam computed tomography (CBCT) is lacking. PURPOSE: The purpose of this clinical study was to evaluate CBCT images of edentulous patients to analyze the feasibility of implant placement in healed mandibular molar sites. MATERIAL AND METHODS: The CBCT data of 138 patients were analyzed in the sagittal plane for measurements of mandibular bone height (MBH), superior bone height (SBH), inferior bone height (IBH), buccal bone width (BBW), lingual bone width (LBW), and alveolar bone widths (ABWs). The edentulous sites were categorized according to the bone quantity and complexity of the implant surgery. Multivariate analysis of variance (MANOVA) was used to analyze the site, sex, and age-related variations. An independent t test was used to compare the difference of bone dimension in different sites and between sexes. One-way ANOVA followed by post hoc tests were used to analyze the difference between different age groups. Categorical variables were presented as number of events and percentages. The chi-squared test was used to compare categorical variables (α=.05). RESULTS: A total of 534 sites of interest were recorded, including 274 hemimandibles. A significant difference in BBW was found between the first and second molar sites. Men had higher MBH, SBH, IBH, and BBW than women. The distribution of implant surgical complexity in the conventional group was 63.5%, while the buccolingual tilted implant group accounted for 17.0%, and the complicated group accounted for 19.5%. Of the 274 hemimandibles, an implant could be placed directly at molar sites in 88% of situations. CONCLUSIONS: The BBW at the mandibular second molar site was greater than that at the first molar site. The amount of available bone in the SBH and BBW was greater in men than in women at the healed molar sites. Age did not significantly affect the complexity of the implant surgery. Implants can be placed directly in healed mandibular molar sites in most patients who require a complete arch mandibular implant-supported restoration.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Implantação Dentária Endóssea , Estudos de Viabilidade , Mandíbula , Dente Molar , Humanos , Tomografia Computadorizada de Feixe Cônico/métodos , Masculino , Feminino , Mandíbula/diagnóstico por imagem , Mandíbula/cirurgia , Estudos Retrospectivos , Dente Molar/diagnóstico por imagem , Pessoa de Meia-Idade , Adulto , Idoso , Implantação Dentária Endóssea/métodos , Arcada Edêntula/diagnóstico por imagem , Arcada Edêntula/cirurgia , Implantes Dentários
5.
EJNMMI Phys ; 11(1): 20, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38386084

RESUMO

BACKGROUND: The endoplasmic reticulum plays an important role in glucose metabolism and has not been explored in the kinetic estimation of hepatocellular carcinoma (HCC) via 18F-fluoro-2-deoxy-D-glucose PET/CT. METHODS: A dual-input four-compartment (4C) model, regarding endoplasmic reticulum was preliminarily used for kinetic estimation to differentiate 28 tumours from background liver tissue from 24 patients with HCC. Moreover, parameter images of the 4C model were generated from one patient with negative findings on conventional metabolic PET/CT. RESULTS: Compared to the dual-input three-compartment (3C) model, the 4C model has better fitting quality, a close transport rate constant (K1) and a dephosphorylation rate constant (k6/k4), and a different removal rate constant (k2) and phosphorylation rate constant (k3) in HCC and background liver tissue. The K1, k2, k3, and hepatic arterial perfusion index (HPI) from the 4C model and k3, HPI, and volume fraction of blood (Vb) from the 3C model were significantly different between HCC and background liver tissues (all P < 0.05). Meanwhile, the 4C model yielded additional kinetic parameters for differentiating HCC. The diagnostic performance of the top ten genes from the most to least common was HPI(4C), Vb(3C), HPI(3C), SUVmax, k5(4C), k3(3C), k2(4C), v(4C), K1(4C) and Vb(4C). Moreover, a patient who showed negative findings on conventional metabolic PET/CT had positive parameter images in the 4C model. CONCLUSIONS: The 4C model with the endoplasmic reticulum performed better than the 3C model and produced additional useful parameters in kinetic estimation for differentiating HCC from background liver tissue.

6.
Hum Vaccin Immunother ; 20(1): 2300208, 2024 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-38191194

RESUMO

Global COVID-19 vaccination programs effectively contained the fast spread of SARS-CoV-2. Characterizing the immunity status of returned populations will favor understanding the achievement of herd immunity and long-term management of COVID-19 in China. Individuals were recruited from 7 quarantine stations in Guangzhou, China. Blood and throat swab specimens were collected from participants, and their immunity status was determined through competitive ELISA, microneutralization assay and enzyme-linked FluoroSpot assay. A total of 272 subjects were involved in the questionnaire survey, of whom 235 (86.4%) were returning Chinese individuals and 37 (13.6%) were foreigners. Blood and throat swab specimens were collected from 108 returning Chinese individuals. Neutralizing antibodies against SARS-CoV-2 were detected in ~90% of returning Chinese individuals, either in the primary or the homologous and heterologous booster vaccination group. The serum NAb titers were significantly decreased against SARS-CoV-2 Omicron BA.5, BF.7, BQ.1 and XBB.1 compared with the prototype virus. However, memory T-cell responses, including specific IFN-γ and IL-2 responses, were not different in either group. Smoking, alcohol consumption, SARS-CoV-2 infection, COVID-19 vaccination, and the time interval between last vaccination and sampling were independent influencing factors for NAb titers against prototype SARS-CoV-2 and variants of concern. The vaccine dose was the unique common influencing factor for Omicron subvariants. Enhanced immunity against SARS-CoV-2 was established in returning Chinese individuals who were exposed to reinfection and vaccination. Domestic residents will benefit from booster homologous or heterologous COVID-19 vaccination after reopening of China, which is also useful against breakthrough infection.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Anticorpos Neutralizantes , China/epidemiologia
7.
Mol Oncol ; 18(3): 580-605, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38060346

RESUMO

Homologous recombination (HR) repair for DNA double-strand breaks (DSBs) is critical for maintaining genome stability and conferring the resistance of tumor cells to chemotherapy. Nuclear PTEN which contains both phosphatidylinositol 3,4,5-trisphosphate 3-phosphatase and protein phosphatase plays a key role in HR repair, but the underlying mechanism remains largely elusive. We find that SUMOylated PTEN promotes HR repair but represses nonhomologous end joining (NHEJ) repair by directly dephosphorylating TP53-binding protein 1 (53BP1). During DNA damage responses (DDR), tumor suppressor ARF (p14ARF) was phosphorylated and then interacted efficiently with PTEN, thus promoting PTEN SUMOylation as an atypical SUMO E3 ligase. Interestingly, SUMOylated PTEN was subsequently recruited to the chromatin at DSB sites. This was because SUMO1 that was conjugated to PTEN was recognized and bound by the SUMO-interacting motif (SIM) of breast cancer type 1 susceptibility protein (BRCA1), which has been located to the core of 53BP1 foci on chromatin during S/G2 stage. Furthermore, these chromatin-loaded PTEN directly and specifically dephosphorylated phosphothreonine-543 (pT543) of 53BP1, resulting in the dissociation of the 53BP1 complex, which facilitated DNA end resection and ongoing HR repair. SUMOylation-site-mutated PTENK254R mice also showed decreased DNA damage repair in vivo. Blocking the PTEN SUMOylation pathway with either a SUMOylation inhibitor or a p14ARF(2-13) peptide sensitized tumor cells to chemotherapy. Our study therefore provides a new mechanistic understanding of PTEN in HR repair and clinical intervention of chemoresistant tumors.


Assuntos
Neoplasias , Proteína Supressora de Tumor p14ARF , Animais , Camundongos , Proteína BRCA1/genética , Cromatina , DNA/metabolismo , Dano ao DNA , Reparo do DNA por Junção de Extremidades , Reparo do DNA , Neoplasias/genética , Proteína Supressora de Tumor p14ARF/genética , Proteína Supressora de Tumor p14ARF/metabolismo
8.
Mol Oncol ; 18(1): 170-189, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37867415

RESUMO

Endoribonuclease DICER is an RNase III enzyme that mainly processes microRNAs in the cytoplasm but also participates in nuclear functions such as chromatin remodelling, epigenetic modification and DNA damage repair. The expression of nuclear DICER is low in most human cancers, suggesting a tight regulation mechanism that is not well understood. Here, we found that ubiquitin carboxyl-terminal hydrolase 7 (USP7), a deubiquitinase, bounded to DICER and reduced its nuclear protein level by promoting its ubiquitination and degradation through MDM2, a newly identified E3 ubiquitin-protein ligase for DICER. This USP7-MDM2-DICER axis impaired histone γ-H2AX signalling and the recruitment of DNA damage response (DDR) factors, possibly by influencing the processing of small DDR noncoding RNAs. We also showed that this negative regulation of DICER by USP7 via MDM2 was relevant to human tumours using cellular and clinical data. Our findings revealed a new way to understand the role of DICER in malignant tumour development and may offer new insights into the diagnosis, treatment and prognosis of cancers.


Assuntos
Neoplasias , Ribonuclease III , Humanos , Dano ao DNA , Reparo do DNA , Neoplasias/genética , Neoplasias/tratamento farmacológico , Proteínas Nucleares/genética , Ribonuclease III/genética , Ribonuclease III/metabolismo , Ubiquitina Tiolesterase/genética , Ubiquitina Tiolesterase/metabolismo , Peptidase 7 Específica de Ubiquitina/genética , Peptidase 7 Específica de Ubiquitina/metabolismo , Ubiquitinação
9.
J Craniomaxillofac Surg ; 52(1): 23-29, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38129182

RESUMO

The aim of this study was to introduce and report on a 3D-printed perforator navigator and its clinical application. Integrated imaging and 3D printing techniques were employed for the design and manufacture of a perforator navigator. Key techniques included establishing a digital image coordinate system, localizing perforator fascia piercing points, creating a reference plane for the perforator course, and projecting the perforator course onto the body surface. All cases of maxillofacial defect repaired with free fibular myocutaneous flaps, from January 2019 to January 2022, were reinvestigated. Patients treated using traditional perforator localization methods were assigned into group Ⅰ, while those who had a navigator used during treatment were allocated to group Ⅱ. Outcome measurements included perforator positioning accuracy, perforator preparation time (PT), and flap growth score. Capillary refilling time and degree of flap swelling were recorded on the 1st, 3rd, and 7th days after surgery. On the 10th day after surgery, the flap survival situation was graded. In total, 25 patients were included in the study. Perforator preparation time for group Ⅱ was significantly less (p = 0.04) than for group Ⅰ (1038.6 ± 195.4 s versus 1271.4 ± 295.1 s. In group Ⅱ, the mean positioning deviation for the perforator navigator was 2.12 cm less than that for the high-frequency color Doppler (p = 0.001). Group Ⅱ also had a higher score than group Ⅰ for overall flap growth evaluation (nonparametric rank sum test, p = 0.04). Within the scale of the study, it seems that perforator localization and navigation using a 3D-printed navigator is technically feasible, and helps to improve the clinical outcome of free fibular flaps. The perforator navigator will play a useful role in displaying the perforator course, improving the accuracy of perforator localization, reducing surgical injury, and ultimately enhancing flap success rate.


Assuntos
Retalhos de Tecido Biológico , Retalho Miocutâneo , Retalho Perfurante , Procedimentos de Cirurgia Plástica , Lesões dos Tecidos Moles , Humanos , Transplante de Pele , Retalho Perfurante/irrigação sanguínea , Retalho Miocutâneo/cirurgia , Retalhos de Tecido Biológico/cirurgia , Lesões dos Tecidos Moles/cirurgia , Resultado do Tratamento
10.
Nat Commun ; 14(1): 8241, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38086870

RESUMO

The first local mpox outbreak in Guangdong Province, China occurred in June 2023. However, epidemiological data have failed to quickly identify the source and transmission of the outbreak. Here, phylogeny and molecular evolution of 10 monkeypox virus (MPXV) genome sequences from the Guangdong outbreak were characterized, revealing local silent transmissions that may have occurred in Guangdong whose mpox outbreaks suggested a molecular epidemiological correlation with Portugal and several regions of China during the same period. The lineage IIb C.1, which includes all 10 MPXV from Guangdong, shows consistent temporal continuity in both phylogenetic characteristics and unique molecular evolutionary mutation spectrum, reflected in the continuous increase of single nucleotide polymorphisms (SNPs) and shared mutations over time. Compared with the Japan MPXV, the Guangdong MPXV showed higher genomic nucleotide differences and separated 14 shared mutations from the B.1 lineage, comprising 6 non-synonymous mutations in genes linked to host regulation, virus infection, and virus life cycle. The unique mutation spectrum with temporal continuity in IIb C.1, related to apolipoprotein B mRNA-editing catalytic polypeptide-like 3, promotes rapid viral evolution and diversification. The findings contribute to understanding the ongoing mpox outbreak in China and offer insights for developing joint prevention and control strategies.


Assuntos
Monkeypox virus , Mpox , Humanos , Filogenia , Monkeypox virus/genética , Surtos de Doenças , Evolução Molecular
11.
Medicine (Baltimore) ; 102(35): e34778, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37657062

RESUMO

Thyroid-associated ophthalmopathy (TAO) is an autoimmune disease involving the ocular tissues that may require strabismus surgery treatment. Presently, little is known about the impact of strabismus surgery on the quality of life of such patients. Consequently, the aim of the present study was to explore the effect of strabismus surgery on the quality of life of strabismus patients with quiescent TAO. This was a prospective case-series study. Strabismus patients with TAO who were admitted to the First Affiliated Hospital of Guangxi Medical University for strabismus surgery from October 2011 to April 2016 were included in this study. The included patients were asked to complete the Graves' ophthalmopathy quality of life questionnaire (GO-QOL) before strabismus surgery and 6 weeks after the surgery, respectively. Preoperative and postoperative GO-QOL scores were compared using the paired samples t-test. The correlation between strabismus surgery and the quality of life was analyzed using Spearman correlation analysis. In total, 23 patients, with a mean age of 49.04 years old, were included in the study. Compared to the preoperative GO-QOL scores, the postoperative scores of these patients for visual function (43.04 vs 73.50, P < .001) and psychosocial function (40.13 vs 72.93, P < .001) were both significantly increased. The greater the preoperative angle of misalignment of the eyes, the worse the psychosocial function (r = -0.433, P = .039). Strabismus surgery can significantly improve the quality of life of strabismus patients with quiescent TAO.


Assuntos
Oftalmopatia de Graves , Estrabismo , Humanos , Pessoa de Meia-Idade , Oftalmopatia de Graves/complicações , Oftalmopatia de Graves/cirurgia , Qualidade de Vida , China , Estrabismo/cirurgia , Olho
12.
Quant Imaging Med Surg ; 13(5): 2989-3000, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-37179911

RESUMO

Background: The preoperative differentiation between benign parotid gland tumors (BPGTs) and malignant parotid gland tumors (MPGTs) is of great significance for therapeutic decision-making. Deep learning (DL), an artificial intelligence algorithm based on neural networks, can help overcome inconsistencies in conventional ultrasonic (CUS) examination outcomes. Therefore, as an auxiliary diagnostic tool, DL can support accurate diagnosis using massive ultrasonic (US) images. This current study developed and validated a DL-based US diagnosis for the preoperative differentiation of BPGT from MPGT. Methods: A total of 266 patients, including 178 patients with BPGT and 88 patients with MPGT, were consecutively identified from a pathology database and enrolled in this study. Ultimately, considering the limitations of the DL model, 173 patients were selected from the 266 patients and divided into 2 groups: a training set, and a testing set. US images of the 173 patients were used to construct the training set (including 66 benign and 66 malignant PGTs) and testing set (consisting of 21 benign and 20 malignant PGTs). These were then preprocessed by normalizing the grayscale of each image and reducing noise. Processed images were imported into the DL model, which was then trained to predict the images from the testing set and evaluated for performance. Based on the training and validation datasets, the diagnostic performance of the 3 models was assessed and verified using receiver operating characteristic (ROC) curves. Ultimately, before and after combining the clinical data, we compared the area under the curve (AUC) and diagnostic accuracy of the DL model with the opinions of trained radiologists to evaluate the application value of the DL model in US diagnosis. Results: The DL model showed a significantly higher AUC value compared to doctor 1 + clinical data, doctor 2 + clinical data, and doctor 3 + clinical data (AUC =0.9583 vs. 0.6250, 0.7250, and 0.8025 respectively; all P<0.05). In addition, the sensitivity of the DL model was higher than the sensitivities of the doctors combined with clinical data (97.2% vs. 65%, 80%, and 90% for doctor 1 + clinical data, doctor 2 + clinical data, and doctor 3 + clinical data, respectively; all P<0.05). Conclusions: The DL-based US imaging diagnostic model has excellent performance in differentiating BPGT from MPGT, supporting its value as a diagnostic tool for the clinical decision-making process.

13.
Insights Imaging ; 14(1): 98, 2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37226012

RESUMO

BACKGROUND: Kinetic estimation provides fitted parameters related to blood flow perfusion and fluorine-18-fluorodeoxyglucose (18F-FDG) transport and intracellular metabolism to characterize hepatocellular carcinoma (HCC) but usually requires 60 min or more for dynamic PET, which is time-consuming and impractical in a busy clinical setting and has poor patient tolerance. METHODS: This study preliminarily evaluated the equivalence of liver kinetic estimation between short-term (5-min dynamic data supplemented with 1-min static data at 60 min postinjection) and fully 60-min dynamic protocols and whether short-term 18F-FDG PET-derived kinetic parameters using a three-compartment model can be used to discriminate HCC from the background liver tissue. Then, we proposed a combined model, a combination of the maximum-slope method and a three-compartment model, to improve kinetic estimation. RESULTS: There is a strong correlation between the kinetic parameters K1 ~ k3, HPI and [Formula: see text] in the short-term and fully dynamic protocols. With the three-compartment model, HCCs were found to have higher k2, HPI and k3 values than background liver tissues, while K1, k4 and [Formula: see text] values were not significantly different between HCCs and background liver tissues. With the combined model, HCCs were found to have higher HPI, K1 and k2, k3 and [Formula: see text] values than background liver tissues; however, the k4 value was not significantly different between HCCs and the background liver tissues. CONCLUSIONS: Short-term PET is closely equivalent to fully dynamic PET for liver kinetic estimation. Short-term PET-derived kinetic parameters can be used to distinguish HCC from background liver tissue, and the combined model improves the kinetic estimation. CLINICAL RELEVANCE STATEMENT: Short-term PET could be used for hepatic kinetic parameter estimation. The combined model could improve the estimation of liver kinetic parameters.

14.
Med Phys ; 50(5): 2860-2871, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36435974

RESUMO

BACKGROUND: Dynamic PET/CT combined with a dual-input three-compartment model can be applied to assess the kinetic parameters of hepatocellular carcinoma (HCC). The nonlinear least squares (NLLS) method is the most common method for fitting model parameters; however, some limitations remain. PURPOSE: A novel Bayesian-based method was compared with the NLLS method to estimate the kinetic parameters for differentiating HCCs from background liver tissue. METHODS: The proposed Bayesian method combined a priori knowledge of the physiological range and likelihood functions of HCC lesions to obtain HCC PET/CT measurements. Metropolis-Hastings sampling was used to numerically estimate the posterior distribution. This study used 5-minute dynamic PET imaging and 1-minute static PET imaging acquired 60 min post-injection from 19 HCC lesions and 17 background liver regions. RESULTS: The NLLS method indicated that k3 (p = 0.001) and fa (p < 0.001) were higher in HCCs than in background liver tissue, while K1 (p = 0.603), k2 (p = 0.405), k4 (p = 0.492), Vb (p = 0.112), and Ki (p = 0.091) were not significantly different. The Bayesian method showed that k3 (p < 0.001), fa (p < 0.001), and Ki (p = 0.002) were higher in HCCs than in background liver tissue, while K1 (p = 0.195), k2 (p = 0.028), k4 (p = 0.723), and Vb (p = 0.018) were not significantly different. For k3 and fa, the Bayesian method showed a higher AUC value for diagnostic performance in differentiating HCCs from background liver tissue than the NLLS method (0.853 vs. 0.745 and 0.928 vs. 0.886). Additionally, the Bayesian method had smaller Akaike information criteria and residual sum of squares values, as well as fewer parameter estimation outliers, than the NLLS method. CONCLUSIONS: The proposed Bayesian method can accurately and robustly estimate liver kinetic parameters, effectively distinguish between lesions and background liver tissue, and provide accurate information about the uncertainty in parameter estimation.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico por imagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Fluordesoxiglucose F18 , Teorema de Bayes , Neoplasias Hepáticas/diagnóstico por imagem , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos
15.
J Stomatol Oral Maxillofac Surg ; 124(1): 101261, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35961510

RESUMO

OBJECTIVES: The semiburied design of the traditional internal distractor has a relatively high risk of infection and aesthetic problems. To reduce these potential risks, a modified internal distractor with design of pre-embedding curvilinear rail, drive screw, and universal joint was invented. Its stress distribution characteristics and the effect on curvilinear distraction osteogenesis (DO) in vivo were further tested. MATERIALS AND METHODS: Finite element analysis (FEA) was performed on a model of the human mandible and distraction device to measure the stress distribution during curvilinear DO. Six beagles underwent curvilinear DO and consolidation using the new device. Radiological and histological examinations were performed on the new bone. RESULTS: On FEA, the stress was concentrated in the condyle (128.6 MPa) and curved guide rails (324.8 MPa). Four of the six animals completed the DO period and were consolidated for 12 weeks. Secondary infections were not observed. Radiography showed that a new fan-shaped bone-15.5 ± 5.5 mm in length and 4.6 ± 1.6 mm in height-was formed in the bone gap. Micro-computed tomography and histological examinations of specimens indicated that the structure of the new bone was similar to that of the normal bone. CONCLUSIONS: The modified internal curvilinear distraction device meets the mechanical strength requirement and achieve curvilinear DO in animal experiments.


Assuntos
Experimentação Animal , Osteogênese por Distração , Cães , Humanos , Animais , Análise de Elementos Finitos , Microtomografia por Raio-X , Mandíbula/cirurgia , Mandíbula/patologia , Osteogênese por Distração/métodos , Parafusos Ósseos
16.
Oncogene ; 41(44): 4877-4892, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36192478

RESUMO

PTEN is frequently mutated in human cancers, which leads to the excessive activation of PI3K/AKT signaling and thus promotes tumorigenesis and drug resistance. Met1-linked ubiquitination (M1-Ubi) is also involved in cancer progression, but the mechanism is poorly defined. Here we find that HOIP, one important component of linear ubiquitin chain assembly complex (LUBAC), promotes prostate cancer (PCa) progression by enhancing AKT signaling in a PTEN-dependent manner. Mechanistically, PTEN is modified by M1-Ubi at two sites K144 and K197, which significantly inhibits PTEN phosphatase activity and thus accelerates PCa progression. More importantly, we identify that the high-frequency mutants PTENR173H and PTENR173C in PCa patients showed the enhanced level of M1-Ubi, which impairs PTEN function in inhibition of AKT phosphorylation and cell growth. We also find that HOIP depletion sensitizes PCa cells to therapeutic agents BKM120 and Enzalutamide. Furthermore, the clinical data analyses confirm that HOIP is upregulated and positively correlated with AKT activation in PCa patient specimen, which may promote PCa progression and increase the risk of PCa biochemical relapse. Together, our study reveals a key role of PTEN M1-Ubi in regulation of AKT activation and PCa progression, which may propose a new strategy for PCa therapy.


Assuntos
PTEN Fosfo-Hidrolase , Neoplasias da Próstata , Masculino , Humanos , PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Linhagem Celular Tumoral , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/genética , Ubiquitinação
17.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 39(5): 937-944, 2022 Oct 25.
Artigo em Chinês | MEDLINE | ID: mdl-36310482

RESUMO

Cutaneous malignant melanoma is a common malignant tumor. Accurate segmentation of the lesion area is extremely important for early diagnosis of the disease. In order to achieve more effective and accurate segmentation of skin lesions, a parallel network architecture based on Transformer is proposed in this paper. This network is composed of two parallel branches: the former is the newly constructed multiple residual frequency channel attention network (MFC), and the latter is the visual transformer network (ViT). First, in the MFC network branch, the multiple residual module and the frequency channel attention module (FCA) module are fused to improve the robustness of the network and enhance the capability of extracting image detailed features. Second, in the ViT network branch, multiple head self-attention (MSA) in Transformer is used to preserve the global features of the image. Finally, the feature information extracted from the two branches are combined in parallel to realize image segmentation more effectively. To verify the proposed algorithm, we conducted experiments on the dermoscopy image dataset published by the International Skin Imaging Collaboration (ISIC) in 2018. The results show that the intersection-over-union (IoU) and Dice coefficients of the proposed algorithm achieve 90.15% and 94.82%, respectively, which are better than the latest skin melanoma segmentation networks. Therefore, the proposed network can better segment the lesion area and provide dermatologists with more accurate lesion data.


Assuntos
Melanoma , Neoplasias Cutâneas , Humanos , Dermoscopia/métodos , Redes Neurais de Computação , Melanoma/diagnóstico por imagem , Melanoma/patologia , Neoplasias Cutâneas/diagnóstico por imagem , Neoplasias Cutâneas/patologia , Processamento de Imagem Assistida por Computador/métodos , Melanoma Maligno Cutâneo
18.
ACS Nano ; 16(10): 15850-15861, 2022 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-35984218

RESUMO

Present artificial muscles have been suffering from poor actuation step precision and the need of energy input to maintain actuated states due to weak interactions between guest and host materials or the unstable structural changes. Herein, these challenges are addressed by deploying a mechanism of reversible faradaic insertion and extraction reactions between tetrachloroaluminate ions and collapsed carbon nanotubes. This mechanism allows tetrachloroaluminate ions as a strong but dynamic "locker" to achieve an energy-free high-tension catch state and programmable stepwise actuation in the yarn muscle. When powered off, the muscle nearly 100% maintained any achieved contractile strokes even under loads up to 96,000 times the muscle weight. The actuation mechanism allowed the programmable control of stroke steps down to 1% during reversible actuation. The isometric stress generated by the yarn muscle (14.6 MPa in maximum, 40 times that of skeletal muscles) was also energy freely lockable and step controllable with high precision. Importantly, when fully charged, the muscle stored energy with a high capacity of 102 mAh g-1, allowing the muscle as a battery to power secondary muscles or other devices.


Assuntos
Nanotubos de Carbono , Nanotubos de Carbono/química , Alumínio , Contração Muscular , Músculo Esquelético , Íons
19.
Genes (Basel) ; 13(5)2022 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-35627209

RESUMO

Acute urethral injuries caused by urethral endoscopy and other mechanical injuries are the main reasons for secondary infection and late urethral stricture. However, there are no studies to explore the transcriptomic changes in urethral injury and the molecular mechanism of urethral injury, which is important for the treatment and cure of urethral injury. Therefore, we used RNA-seq and sRNA-seq profiles from normal and injured urethral tissues to identify and characterize differentially expressed mRNAs and miRNAs. In total, we found 166 differentially expressed mRNAs, of which 69 were upregulated, and 97 were downregulated in injured urethral tissues. The differentially expressed mRNAs were mainly involved in the positive regulation of epithelial cell differentiation, focal adhesion, cell adhesion molecules, protein activation cascade, complement activation, complement and coagulation cascades, and chemokine-mediated signaling pathway. Additionally, we found six upregulated and four downregulated miRNAs, respectively, in the injured urethral tissues. Notably, their target genes were involved in the vascular endothelial growth factor receptor 2 binding, PI3k-Akt signaling pathway, and Notch signaling pathway. In summary, our results suggest that the cell damage response induced by mechanical injury activates the pathological immune response in a variety of ways in injured urethral tissues.


Assuntos
MicroRNAs , Animais , Sequenciamento de Nucleotídeos em Larga Escala , MicroRNAs/genética , MicroRNAs/metabolismo , Fosfatidilinositol 3-Quinases/genética , RNA Mensageiro/genética , Ratos , Fator A de Crescimento do Endotélio Vascular/genética
20.
BMC Med Imaging ; 22(1): 20, 2022 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-35125095

RESUMO

BACKGROUND: Kinetic parameters estimated with dynamic 18F-FDG PET/CT can help to characterize hepatocellular carcinoma (HCC). We aim to evaluate the feasibility of the gravitational search algorithm (GSA) for kinetic parameter estimation and to propose a dynamic chaotic gravitational search algorithm (DCGSA) to enhance parameter estimation. METHODS: Five-minute dynamic PET/CT data of 20 HCCs were prospectively enrolled, and the kinetic parameters k1 ~ k4 and the hepatic arterial perfusion index (HPI) were estimated with a dual-input three-compartment model based on nonlinear least squares (NLLS), GSA and DCGSA. RESULTS: The results showed that there were significant differences between the HCCs and background liver tissues for k1, k4 and the HPI of NLLS; k1, k3, k4 and the HPI of GSA; and k1, k2, k3, k4 and the HPI of DCGSA. DCGSA had a higher diagnostic performance for k3 than NLLS and GSA. CONCLUSIONS: GSA enables accurate estimation of the kinetic parameters of dynamic PET/CT in the diagnosis of HCC, and DCGSA can enhance the diagnostic performance.


Assuntos
Algoritmos , Carcinoma Hepatocelular/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Neoplasias Hepáticas/diagnóstico por imagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Feminino , Fluordesoxiglucose F18 , Humanos , Masculino , Compostos Radiofarmacêuticos
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