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1.
FASEB J ; : fj201900782R, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31693862

RESUMO

In female mammals, the majority of primordial follicles (PFs) are physiologically quiescent, and only a few of them are activated and enter the growing follicle pool. Specific molecules, such as mammalian target of rapamycin (mTOR) and the serine/threonine kinase Akt (AKT), have been proven to be important for PF activation. However, how the transcription of these genes is regulated is not clear. Although activators of mTOR or AKT have been successfully used to rescue the fertility of patients with premature ovarian insufficiency, the low efficacy and unclear safety profile of these drugs hinder their clinical use in the in vitro activation (IVA) of PFs. Here, sirtuin 1 (SIRT1), an NAD-dependent deacetylase, was demonstrated to activate mouse PFs independent of its deacetylase activity. SIRT1 was prominently expressed in pregranulosa cells (pGCs) and oocytes, and its expression was increased during PF activation. PF activation was achieved by either up-regulating SIRT1 with a specific activator or overexpressing SIRT1. Moreover, SIRT1 knockdown in oocytes or pGCs could significantly suppress PF activation. Further studies demonstrated that SIRT1 enhanced both Akt1 and mTOR expression by acting more as a transcription cofactor, directly binding to the respective gene promoters, than as a deacetylase. Importantly, we explored the potential clinical applications of targeting SIRT1 in IVA via short-term treatment of cultured ovaries from mice and human ovarian tissues to activate PFs by applying the SIRT1 activator resveratrol. RSV-induced IVA could be a candidate strategy to develop more efficient procedures for future clinical treatment of infertility.-Zhang, T., Du, X., Zhao, L., He, M., Lin, L., Guo, C., Zhang, X., Han, J., Yan, H., Huang, K., Sun, G., Yan, L., Zhou, B., Xia, G., Qin, Y., Wang, C. SIRT1 facilitates primordial follicle recruitment independent of deacetylase activity through directly modulating Akt1 and mTOR transcription.

2.
Artigo em Inglês | MEDLINE | ID: mdl-31705175

RESUMO

PURPOSE: Accurate evaluation of hypoxia is particularly important in patients with nasopharyngeal carcinoma (NPC) undergoing radiotherapy. The aim of this study was to propose a novel imaging strategy for quantitative three-dimensional (3D) evaluation of hypoxia in a small animal model of NPC. METHODS: A carbonic anhydrase IX (CAIX)-specific molecular probe (CAIX-800) was developed for imaging of hypoxia. Mouse models of subcutaneous, orthotopic, and spontaneous lymph node metastasis from NPC (5 mice per group) were established to assess the imaging strategy. A multi-modality imaging method that consisted of a hybrid combination of fluorescence molecular tomography-computed tomography (FMT-CT) and multispectral optoacoustic tomography (MSOT) was used for 3D quantitative evaluation of tumour hypoxia. Magnetic resonance imaging, histological examination, and immunohistochemical analysis were used as references for comparison and validation. RESULTS: In the early stage of NPC (2 weeks after implantation), FMT-CT enabled precise 3D localisation of the hypoxia biomarker with high sensitivity. At the advanced stage (6 weeks after implantation), MSOT allowed multispectral analysis of the biomarker and haemoglobin molecules with high resolution. The combination of high sensitivity and high resolution from FMT-CT and MSOT could not only detect hypoxia in small-sized NPCs but also visualise the heterogeneity of hypoxia in 3D. CONCLUSIONS: Integration of FMT-CT and MSOT could allow comprehensive and quantifiable evaluation of hypoxia in NPC. These findings may potentially benefit patients with NPC undergoing radiotherapy in the future. Graphical abstract A novel multimodality imaging strategy for three-dimensional evaluation of tumour hypoxia in an orthotopic model of nasopharyngeal carcinoma.

3.
J Endod ; 2019 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-31676043

RESUMO

The palatogingival groove is a developmental anomaly that typically starts near the cingulum of the maxillary incisors and extends along the roots at varying lengths and depths. Severe grooves that extend to the root apex often lead to complex combined periodontal-endodontic lesions. There are various therapeutic options available for these cases; however, the prognosis is unfavorable. Here, we report the successful surgical treatment of 3 cases of maxillary lateral incisors with severe palatogingival grooves using intentional replantation with a 2-segment restoration method. The teeth were gently extracted, resulting in minimal damage to the periodontal ligament. Under a dental operating microscope, 3 mm of the root end was resected. The palatogingival groove was removed, and root-end preparation was performed with a #700 fissure bur. The groove cavity was connected with root-end cavity to form a class II cavity. The cavity was then filled using a 2-segment restoration method (ie, dividing the cavity into 2 parts by the cementoenamel junction, the coronal portion was filled with a flowable composite while the radicular portion, including the root-end cavity, was filled with bioceramics). The tooth was then replanted into its alveolar bone and splinted with a flexible splint for 7 days. The sinus tract was closed at the 1-week postoperative visit. During subsequent recalls, the teeth showed almost complete periapical healing. In summary, intentional replantation with a 2-segment restoration method is a viable treatment modality for single-rooted teeth with a severe palatogingival groove that extends to the root apex.

4.
Virol J ; 16(1): 129, 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31699105

RESUMO

BACKGROUND: Severe fever with thrombocytopenia syndrome (SFTS) is an emerging hemorrhagic fever that was first described in China in 2011. We report a patient who died of Severe fever with thrombocytopenia syndrome virus (SFTSV) infection, with a rapidly progressive central nervous system (CNS) disturbance, in Dongyang, Zhejiang Province, China, in 2017. CASE PRESENTATION: A 64-year-old man was admitted to hospital after 4 days of fever. SFTSV was detected 1 day after the patient was admitted to hospital. The patient presented with CNS disturbance and died 4 days after admission. Detailed clinical and epidemiological investigations and laboratory tests were conducted. Reduced platelet, white blood cell, lymphocyte, and neutrophil counts, elevated lactate dehydrogenase, creatine kinase, aspartate aminotransferaseand alanine aminotransferase concentrations, and an increased activated partial thromboplastin time were observed. In a phylogenetic analysis, the isolate clustered close to a strain derived from South Korea. CONCLUSIONS: This is the first case of SFTSV infection with CNS disturbance in Dongyang, Zhejiang Province, China. The surveillance of suspected cases of SFTS is important in SFTSV endemic regions.

6.
Chem Commun (Camb) ; 55(82): 12412, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31577292

RESUMO

Correction for 'Robust magnetic double-network hydrogels with self-healing, MR imaging, cytocompatibility and 3D printability' by Fangli Gang et al., Chem. Commun., 2019, 55, 9801-9804.

7.
Adv Ther ; 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31598901

RESUMO

INTRODUCTION: The effect of N-acetylcysteine (NAC) treatment for patients with chronic bronchitis (CB) is controversial. To better understand the role of NAC in CB treatment, we performed a meta-analysis to provide a more accurate estimation of the importance of NAC treatment. METHODS: PubMed, Embase, and CNKI were systematically searched. The pooled relative risk (RR) and 95% confidence intervals (CI) were calculated using either fixed-effect model or random-effect model based on heterogeneity examination. Statistical analyses were performed using the STATA 12.0 and RevMan 5.2. RESULTS: A total of 11 publications with 775 patients who were taking NAC and 789 controls who were taking placebo were judged eligible regarding inclusion criteria. The pooled analysis demonstrated significant evidence that NAC reduced the frequency of CB exacerbations (RR = 0.81, 95% CI 0.69-0.93, P = 0.004). Patients treated with NAC had significant symptom improvement compared with controls (RR = 1.68, 95% CI 1.13-2.52, P = 0.01). NAC did not significantly increase the risk of adverse effects compared with placebo (RR 0.86, 95% CI 0.67-1.09, P = 0.22). Subgroup analysis was carried out to assess the stability of results. No publication bias was detected during analyses. CONCLUSION: There is a role for NAC treatment in the management of CB by reducing symptoms and exacerbations compared with placebo, without increasing the risk of adverse effects. A regular treatment of low dosage (< 1200 mg per day) and a duration of at least 3 months seems to be effective.

8.
Toxicol Appl Pharmacol ; 383: 114768, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31639374

RESUMO

Crizotinib is an oral small-molecule tyrosine kinase inhibitor targeting anaplastic lymphoma kinase (ALK), ROS proto-oncogene 1, receptor tyrosine kinase (ROS1) and MET proto-oncogene, receptor tyrosine kinase (MET). Unfortunately, hepatotoxicity is a serious limitation in its clinical application, and the reason remains largely unknown. In this study, we tested the effect of crizotinib in human hepatocyte cell line HL-7702 and human primary hepatocytes, and the results showed that crizotinib treatment caused hepatocyte damage, suggesting that crizotinib induced liver injury by causing hepatocyte death, consistent with the clinical cases. Mechanistically, crizotinib induced hepatocyte death via the apoptotic pathway, and cleaved PARP (c-PARP) was observed as a signaling protein. Moreover, mitochondrial membrane potential (MMP) decrease contributed to crizotinib-induced hepatocyte apoptosis accompanied by hepatocyte DNA damage and reactive oxygen species (ROS) generation. Importantly, crizotinib induced hepatocyte apoptosis independent of its targets, ALK, ROS1 and MET. In conclusion, our data showed that crizotinib induced liver injury through hepatocyte death via the apoptotic pathway which was independent of ALK, ROS1 and MET. And we also found that MMP decrease, DNA damage and ROS generation were involved in the process.

9.
Mol Hum Reprod ; 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31633177

RESUMO

Prostaglandin E2 (PGE2) is a hormone with many physiological functions. During pregnancy, it is generally believed that there is a high level of PGE2 at the final stage of pregnancy, which induces the contraction of uterine smooth muscle and promotes the occurrence of childbirth. However, we find that high PGE2 levels are present throughout late pregnancy in mice, not just during childbirth, and that PGE2 deficiency induced by indomethacin during late pregnancy causes damage to the placental labyrinth and eventually leads to abortion. Interestingly, the damage is closely related to inflammation, which involves the role of inflammatory factors produced by the periaortic lymph nodes (PLNs) near the uterus. Further, through RNA sequencing, we reveal that PLNs produce a large amount of interleukin-1ß (IL-1ß) when exposed to PGE2 deficiency, which causes damage to the placental labyrinth, probably via destroying the extracellular matrix. Finally, events leading to abortion following indomethacin administration are effectively prevented by supplementing PGE2 or by PLN removal. These results suggest that high levels of PGE2 during late pregnancy protect fetuses from inflammatory damage related to IL-1ß. This work suggests a new role of PGE2 during late pregnancy and may provide potential therapeutic strategies for pathological pregnancy.

10.
Sensors (Basel) ; 19(21)2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31661870

RESUMO

In the process of rehabilitation training for stroke patients, the rehabilitation effect is positively affected by how much physical activity the patients take part in. Most of the signals used to measure the patients' participation are EMG signals or oxygen consumption, which increase the cost and the complexity of the robotic device. In this work, we design a multi-sensor system robot with torque and six-dimensional force sensors to gauge the patients' participation in training. By establishing the static equation of the mechanical leg, the man-machine interaction force of the patient can be accurately extracted. Using the impedance model, the auxiliary force training mode is established, and the difficulty of the target task is changed by adjusting the K value of auxiliary force. Participation models with three intensities were developed offline using support vector machines, for which the C and σ parameters are optimized by the hybrid quantum particle swarm optimization and support vector machines (Hybrid QPSO-SVM) algorithm. An experimental statistical analysis was conducted on ten volunteers' motion representation in different training tasks, which are divided into three stages: over-challenge, challenge, less challenge, by choosing characteristic quantities with significant differences among the various difficulty task stages, as a training set for the support vector machines (SVM). Experimental results from 12 volunteers, with tasks conducted on the lower limb rehabilitation robot LLR-II show that the rehabilitation robot can accurately predict patient participation and training task difficulty. The prediction accuracy reflects the superiority of the Hybrid QPSO-SVM algorithm.

11.
Mol Microbiol ; 2019 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-31628680

RESUMO

BldD generally functions as a repressor controlling morphological development of Streptomyces. In this work, evidences that BldD also activates antibiotic production are provided. In Streptomyces roseosporus (which produces daptomycin widely used for treatment of human infections), deletion of bldD notably reduced daptomycin production, but enhanced sporulation. BldD stimulated daptomycin production by directly activating transcription of dpt structural genes and dptR3 (which encodes an indirect activator of daptomycin production), and repressed its own gene. BldD-binding sites on promoter regions of dptE, dptR3, and bldD were all found to contain BldD box-like sequences, facilitating prediction of new BldD targets. Two Streptomyces global regulatory genes, adpA and afsR, were confirmed to be directly activated by BldD. The protein AfsR was shown to act as an activator of daptomycin production, but a repressor of development. BldD directly represses nine key developmental genes. In Streptomyces avermitilis (which produces effective anthelmintic agents avermectins), BldD homolog (BldDsav) directly activates avermectin production through ave structural genes and cluster-situated activator gene aveR. This is the first report that BldD activates antibiotic biosynthesis both directly and via a cascade mechanism. BldD homologs are widely distributed among Streptomyces, our findings suggest that BldD may activate antibiotic production in other Streptomyces species.

12.
Biol Trace Elem Res ; 2019 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-31473893

RESUMO

Arsenic trioxide (ATO), a trivalent arsenic compound, is known to disrupt redox homeostasis. Methionine sulfoxide reductases (Msrs), a group of antioxidant proteins, convert methionine sulfoxide back to methionine in living organisms exposed to oxidative stress. The objective of this study was to determine the effects of ATO on oxidative stress and the expressions of Msrs in mouse liver. Sixty male mice were randomly divided into six equal groups: one control group and five groups that received ATO treatment (0.3, 1, 3, 6, and 9 mg/kg, respectively). After a 4-week treatment, livers specimens were collected and assayed for malonyldialdehyde (MDA) content, superoxide dismutase (SOD) activity, total antioxidant capacity (T-AOC), and glutathione peroxidase (GSH-Px) activity. In addition, the mRNA expressions of SOD-1 and HO-1 and the mRNA and protein expressions of Msrs were also determined. Results showed that the T-AOC activity, SOD activity, and SOD-1 mRNA expression were significantly decreased (P < 0.01), while the GSH-Px level, MDA content, and HO-1 mRNA expression were significantly increased in mice treated with ATO compared with control. Levels of MsrB2 mRNA and MsrA protein were significantly increased by ATO treatment, except in the highest dose group. There were no significant changes in MsrB3 mRNA level. ATO, at 1 or 3 mg/kg, increased MsrB1 expression. Modifications in MsrA protein level were consistent with changes in mRNA levels. Collectively, our results suggest that ATO induced oxidative stress and then led to the variations in Msrs activity in mouse liver.

13.
Artigo em Inglês | MEDLINE | ID: mdl-31532864

RESUMO

With the picolinyl (Pic) group as a C-1 located directing group and N3 as versatile precursor for C5-NH2 , a novel 1-Pic-5-N3 thiosialyl donor was designed and synthesized, based on which a new sialylation protocol was established. In comparison to conventional sialylation methods, the new protocol exhibited obvious advantages, including excellent α-stereoselectivity in the absence of a solvent effect, broad substrate scope encompassing the challenging sialyl 8- and 9-hydroxy groups of sialic acid acceptors, flexibility in sialoside derivative synthesis, high temperature tolerance and easy scalability. In particular, the applicability to the synthesis of complex and bioactive N-glycan antennae when combined with the MPEP glycosylation protocol via the "latent-active" strategy has been shown. Mechanistically, the excellent α-stereoselectivity of the novel sialylation protocol could be attributed to the dramatic electron-withdrawing effect of the protonated Pic groups, which was supported by control reactions and DFT calculations.

14.
Expert Opin Drug Metab Toxicol ; 15(9): 767-774, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31478386

RESUMO

Introduction: The phosphatidylinositide 3-kinase/AKT/mammalian target of rapamycin (PI3K/AKT/mTOR) signaling pathway has emerged as an important target in cancer therapy. Numerous PI3K/AKT/mTOR pathway inhibitors are extensively studied; some are used clinically, but most of these drugs are undergoing clinical trials. Potential adverse effects, such as severe hepatotoxicity and pneumonitis, have largely restricted the application and clinical significance of these inhibitors. A summary of mechanisms underlying the adverse effects is not only significant for the development of novel PI3K/AKT/mTOR inhibitors but also beneficial for the optimal use of existing drugs. Areas covered: We report a profile of the adverse effects, which we consider the class effects of PI3K/AKT/mTOR inhibitors. This review also discusses potential molecular toxicological mechanisms of these agents, which might drive future drug discovery. Expert opinion: Severe toxicities associated with PI3K/AKT/mTOR inhibitors hinder their approval and limit long-term clinical application of these drugs. A better understanding regarding PI3K/AKT/mTOR inhibitor-induced toxicities is needed. However, the mechanisms underlying these toxicities remain unclear. Future research should focus on developing strategies to reduce toxicities of approved inhibitors as well as accelerating new drug development. This review will be useful to clinical, pharmaceutical, and toxicological researchers.


Assuntos
Antineoplásicos/efeitos adversos , Descoberta de Drogas/métodos , Inibidores de Proteínas Quinases/efeitos adversos , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacologia , Humanos , Fosfatidilinositol 3-Quinase/antagonistas & inibidores , Inibidores de Proteínas Quinases/administração & dosagem , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/antagonistas & inibidores
15.
J Am Chem Soc ; 141(43): 17189-17197, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31539231

RESUMO

Synthetic catalytic DNA circuits are important signal amplification tools for molecular programming due to their robust and modular properties. In catalytic circuits, the reactant recycling operation is essential to facilitate continuous processes. Therefore, it is desirable to develop new methods for the recycling of reactants and to improve the recyclability in entropy-driven DNA circuit reactions. Here, we describe the implementation of a nicking-assisted recycling strategy for reactants in entropy-driven DNA circuits, in which duplex DNA waste products are able to revert into active components that could participate in the next reaction cycle. Both a single-layered circuit and multiple two-layered circuits of different designs were constructed and analyzed. During the reaction, the single-layered catalytic circuit can consume excess fuel DNA strands without depleting the gate components. The recycling of the two-layered circuits occurs during the fuel DNA digestion but not during the release of the downstream trigger. This strategy provides a simple yet versatile method for creating more efficient entropy-driven DNA circuits for molecular programming and synthetic biology.

16.
AJR Am J Roentgenol ; : W1-W11, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31553660

RESUMO

OBJECTIVE. The objective of our study was to compare the performance of radiologicradiomic machine learning (ML) models and expert-level radiologists for differentiation of benign and malignant solid renal masses using contrast-enhanced CT examinations. MATERIALS AND METHODS. This retrospective study included a cohort of 254 renal cell carcinomas (RCCs) (190 clear cell RCCs [ccRCCs], 38 chromophobe RCCs [chrRCCs], and 26 papillary RCCs [pRCCs]), 26 fat-poor angioleiomyolipomas, and 10 oncocytomas with preoperative CT examinations. Lesions identified by four expert-level radiologists (> 3000 genitourinary CT and MRI studies) were manually segmented for radiologicradiomic analysis. Disease-specific support vector machine radiologic-radiomic ML models for classification of renal masses were trained and validated using a 10-fold cross-validation. Performance values for the expert-level radiologists and radiologic-radiomic ML models were compared using the McNemar test. RESULTS. The performance values for the four radiologists were as follows: sensitivity of 73.7-96.8% (median, 84.5%; variance, 122.7%) and specificity of 48.4-71.9% (median, 61.8%; variance, 161.6%) for differentiating ccRCCs from pRCCs and chrRCCs; sensitivity of 73.7-96.8% (median, 84.5%; variance, 122.7%) and specificity of 52.8-88.9% for differentiating ccRCCs from fat-poor angioleiomyolipomas and oncocytomas (median, 80.6%; variance, 269.1%); and sensitivity of 28.1-60.9% (median, 84.5%; variance, 122.7%) and specificity of 75.0-88.9% for differentiating pRCCs and chrRCCs from fat-poor angioleiomyolipomas and oncocytomas (median, 50.0%; variance, 191.1%). After a 10-fold cross-validation, the radiologic-radiomic ML model yielded the following performance values for differentiating ccRCCs from pRCCs and chrRCCs, ccRCCs from fat-poor angioleiomyolipomas and oncocytomas, and pRCCs and chrRCCs from fat-poor angioleiomyolipomas and oncocytomas: a sensitivity of 90.0%, 86.3%, and 73.4% and a specificity of 89.1%, 83.3%, and 91.7%, respectively. CONCLUSION. Expert-level radiologists had obviously large variances in performance for differentiating benign from malignant solid renal masses. Radiologic-radiomic ML can be a potential way to improve interreader concordance and performance.

17.
J Cell Biochem ; 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31478228

RESUMO

Hepatocellular carcinoma (HCC) remains the most common malignant tumor worldwide. Long noncoding RNAs can modulate various tumorigenic processes. In addition, growing evidence has indicated tha the Janus kinase-signal transducer and activator of transcription (JAK-STAT) pathway is activated in multiple cancers, including HCC. Recently, it was found that LINC00346 can participate in several cancers. Nevertheless, the biological roles of LINC00346 in HCC have been barely investigated. In this study, the function of LINC00346 was specifically concentrated upon. We observed that LINC00346 was obviously elevated in HCC cells (Bel7404, Huh-6, HepG2, and QGY-7703 cells). Then, Bel7404 and HepG2 cells were overexpressed with LINC00346. Overexpression of LINC00346 repressed HCC cell survival and cell proliferation. In addition, apoptosis of Bel7404 and HepG2 cells was triggered by LINC00346 upregulation. Bel7404 and HepG2 cell cycle was arrested in the G1 phase by LINC00346. Meanwhile, we conducted wound-healing assay and Transwell invasion assays. As shown, we observed that the migratory and invasive capacities of Bel7404 and HepG2 cells were remarkably restrained by the increase of LINC00346. Moreover, we showed that LINC00346 overexpression activated the JAK-STAT3 pathway, which is involved in many cancers. Afterward, in vivo experiments were utilized and we proved that LINC00346 was able to induce HCC tumor growth via activating the JAK-STAT3 pathway. To conclude, we revealed the potential possibility of developing LINC00346 as an indicator for HCC.

18.
Biomed Res Int ; 2019: 4273108, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31380422

RESUMO

As the incidence of senile dementia continues to increase, researches on Alzheimer's disease (AD) have become more and more important. Several studies have reported that there is a close relationship between AD and aging. Some researchers even pointed out that if we wanted to understand AD in depth, mechanisms of AD based on accelerated aging must be studied. Nowadays, machine learning techniques have been utilized to deal with large and complex profiles, thus playing an important role in disease researches (i.e., modelling biological systems, identifying key modules based on biological networks, and so on). Here, we developed an aging predictor and an AD predictor using machine learning techniques, respectively. Both aging and AD biomarkers were identified to provide insights into genes associated with AD. Besides, aging scores were calculated to reflect the aging process of brain tissues. As a result, the aging acceleration network and the aging-AD bipartite graph were constructed to delve into the relationship between AD and aging. Finally, a series of network and enrichment analyses were also conducted to gain further insights into the mechanisms of AD based on accelerated aging. In a word, our results indicated that aging may contribute to the development of AD by affecting the function of the immune system and the energy metabolism process, where the immune system may play a more prominent role in AD.

19.
Discov Med ; 27(150): 227-233, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31421691

RESUMO

OBJECTIVE: The aim of this study was to investigate the characteristics of nasopharyngeal carcinoma (NPC) using contrast-enhanced ultrasonography (CEUS), including the enhancement patterns and the quantitative parameters. METHODS: Having been scanned using conventional ultrasonography (US) and CEUS, every case was confirmed to be NPC under endoscopic biopsy, and no case received any anti-tumor treatment before CEUS examinations. Tumor/node/metastasis stages were determined in accordance with 2002 AJCC 6th edition. Contrast enhancement patterns and quantitative parameters were observed. RESULTS: CEUS imaging of NPC showed that the tumor signal intensity enhanced early, rapidly, and remarkably, and decreased slowly later. The patterns of enhancement included spot/linear enhancement, peripheral enhancement, and mass enhancement, and two types of time intensity curves of NPC included type I and type II. There was a significant difference between peak intensity (PI) and T stage (P<0.05), whereas time-to-peak (TP) and slope did not show significant differences with T stage (P>0.05). CONCLUSION: CEUS is feasible to be applied to the nasopharynx region. The use of CEUS makes it possible to observe vascular permeability of NPC. Our results suggest that the quantitative parameter PI of nasopharyngeal carcinoma is significantly different from T stages. Thus, PI may serve as a potential noninvasive radiological prognostic indicator for NPC.

20.
Int J Eat Disord ; 52(10): 1150-1156, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31381168

RESUMO

OBJECTIVE: Online forums allow people to semi-anonymously discuss their struggles, often leading to greater honesty. This characteristic makes forums valuable for identifying users in need of immediate help from mental health professionals. Because it would be impractical to manually review every post on a forum to identify users in need of urgent help, there may be value to developing algorithms for automatically detecting posts reflecting a heightened risk of imminent plans to engage in disordered behaviors. METHOD: Five natural language processing techniques (tools to perform computational text analysis) were used on a data set of 4,812 posts obtained from six eating disorder-related subreddits. Two licensed clinical psychologists labeled 53 of these posts, deciding whether or not the content of the post indicated that its author needed immediate professional help. The remaining 4,759 posts were unlabeled. RESULTS: Each of the five techniques ranked the 50 posts most likely to be intervention-worthy (the "top-50"). The two most accurate detection techniques had an error rate of 4% for their respective top-50. DISCUSSION: This article demonstrates the feasibility of automatically detecting-with only a few dozen labeled examples-the posts of individuals in need of immediate mental health support for an eating disorder.

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