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1.
Med Chem Res ; : 1-18, 2022 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-35035203

RESUMO

The dammarane triterpenoid (20S,24R)-epoxy-dammarane-3ß,12ß,25-triol obtained from Cyclocarya paliurus in our previous study showed inhibitory activity on α-glucosidase in vitro with an inhibitory ratio of 32.2% at the concentration of 200 µM. In order to reveal the structure-activity relationships (SARs) and get more active compounds, 42 derivatives of (20S,24R)-epoxy-dammarane-3ß,12ß,25-triol were synthesized by chemical modification on the hydroxyls (C-3 and C-12), rings A and E, and assayed for their α-glucosidase and PTP1B inhibitory activities. Two compounds (8, 26) increased activity against α-glucosidase, and four compounds (8, 15, 26, 42) significantly inhibited PTP1B. It was noted that compounds 8 and 26 could inhibit both α-glucosidase and PTP1B as dual-target inhibitors with IC50 values of 489.8, 467.7 µM (α-glucosidase) and 319.7, 269.1 µM (PTP1B). Compound 26 was revealed to be a mix-type inhibitor on α-glucosidase and a noncompetitive-type inhibitor on PTP1B based on enzyme kinetic study. Furthermore, compound 42 could selectively inhibited PTP1B as a mix-type inhibitor with IC50 value of 134.9 µM, which was 2.5-fold higher than the positive control, suramin sodium (IC50 339.0 µM), but not inhibit α-glucosidase.

2.
Front Med (Lausanne) ; 8: 655013, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34869402

RESUMO

Purpose: To investigate the correlation between retinal capillary structure and macular function in patients with idiopathic epiretinal membrane (iERM) by using optical coherence tomography angiography (OCTA) and microperimetry. Methods: This retrospective and observational study included 30 idiopathic ERM eyes of 30 consecutive patients. OCTA was performed to evaluate macular microvasculature including the superficial capillary plexus, deep capillary plexus, and foveal avascular zone. Best corrected visual acuity (BCVA) and microperimetry were measured at baseline and 3 months after surgery. Associations between macular microvasculature and visual function were assessed. Results: Visual function including BCVA and macular sensitivity improved significantly at 3 months post-operatively (p < 0.001). At baseline, BCVA was positively correlated with foveal or parafoveal sensitivities and negatively correlated with central foveal thickness (p < 0.05). Pre-operative foveal sensitivity was significantly correlated with the vessel density of foveal or parafoveal superficial capillary plexus (p < 0.05). A multiple regression model revealed that pre-operative vessel density of foveal deep capillary plexus was an independent positive prognostic factor for post-operative BCVA (B = -0.020 ± 0.006, p = 0.006) and macular sensitivity (B = 0.200 ± 0.081, p = 0.027). Conclusion: Integrated evaluation of iERM by using OCTA and microperimetry shows an association between microvasculature and macular sensitivity. Pre-operative vessel density of foveal deep capillary plexus assessed by OCTA may be a potentially valuable prognostic factor for iERM surgery.

3.
Dis Markers ; 2021: 9948241, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34721738

RESUMO

Background: Dead end 1 (DND1) plays a vital role during oncogenesis and cancer progression by regulating the mRNA content via competitive combination with miRNA, but what function it exerts in prostate cancer has been unclear. The purpose of this paper is to explore the correlation between DND1 expression levels and clinical characteristics in prostate cancer (PCa) patients. Materials and Methods: To assess the expression of DND1 in tumor specimens compared with paired paracancerous tissues, the sample from 83 patients was analyzed by immunohistochemistry. The Cancer Genome Atlas (TCGA) database was used to verify our results. Subsequently, we statistically analyzed the relationship between DND1 expression and the clinical prognosis of PCa patients. Results: Compared with paracancerous tissues, DND1 has a higher expression level in prostate cancer. The overexpression of DND1 in protein level was significantly associated with the higher clinical stage (P = 0.006), ISUP grading group (P < 0.001), seminal vesicle invasion (P = 0.006), and PSA density (P = 0.002). Furthermore, the overexpression of DND1 indicates a poor clinical prognosis in prostate cancer patients. Conclusion: High-level expression of DND1 was associated with tumor progression and poor clinical prognosis. Hence, DND1 may become a potential prognostic biomarker for PCa.

4.
Sensors (Basel) ; 21(21)2021 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-34770309

RESUMO

Surface electromyography (sEMG) is a kind of biological signal that records muscle activity noninvasively, which is of great significance in advanced human-computer interaction, prosthetic control, clinical therapy, and biomechanics. However, the number of hand gestures that can be recognized is limited and the recognition accuracy needs to be further improved. These factors lead to the fact that sEMG products are not widely used in practice. The main contributions of this paper are as follows. Firstly, considering the increasing number of gestures to be recognized and the complexity of gestures, an extensible two-stage machine learning lightweight framework was innovatively proposed for multi-gesture task recognition. Secondly, the multivariate variational mode decomposition (MVMD) is applied to extract the spatial-temporal features from the multiple channels to the EMG signals, and the separable convolutional neural network is used for modelling. In this work, the experimental results for 52 hand gestures recognition task show that the average accuracy on each stage is about 90%. The potential movement information is mainly contained in the low-frequency oscillator of the sEMG signal, and the model performs better with the low-frequency oscillation from the MVMD algorithm on the second stage classification than that of other decomposition methods.


Assuntos
Gestos , Processamento de Sinais Assistido por Computador , Algoritmos , Eletromiografia , Mãos , Humanos , Redes Neurais de Computação
5.
Rev Environ Health ; 2021 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-34619029

RESUMO

Carbon nanomaterials (CNMs) are ubiquitous in our daily lives because of the outstanding physicochemical properties. CNMs play curial parts in industrial and medical fields, however, the risks of CNMs exposure to human health are still not fully understood. In view of, it is becoming extremely difficult to ignore the existence of the toxicity of CNMs. With the increasing exploitation of CNMs, it's necessary to evaluate the potential impact of these materials on human health. In recent years, more and more researches have shown that CNMs are contributed to the cancer formation and metastasis after long-term exposure through epithelial-mesenchymal transition (EMT) and cancer stem cells (CSCs) which is associated with cancer progression and invasion. This review discusses CNMs properties and applications in industrial and medical fields, adverse effects on human health, especially the induction of tumor initiation and metastasis through EMT and CSCs procedure.

6.
Org Lett ; 23(21): 8380-8384, 2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34634203

RESUMO

The biomimetic synthesis of guaianolide dimers lavandiolides H, I, and K and artematrolide F containing a spirolactone moiety has been accomplished for the first time from naturally abundant arglabin in four to six steps with an overall yield up to 60%, and a series of natural product-like guaianolide dimers, trimer, and tetramer were also successfully synthesized. Notably, the trimeric compound exhibited antihepatoma cytotoxicity more potent than that of sorafenib with IC50 values of 6.2 µM (HepG2), 6.8 µM (Huh7), and 7.2 µM (SK-HEP-1).

7.
Artigo em Inglês | MEDLINE | ID: mdl-34491473

RESUMO

PURPOSE: Abdominal aortic aneurysm (AAA) rupture is one of the most common causes of mortality in cardiovascular diseases, but currently there is no approved drug for AAA treatment or prevention in the clinic. Naringenin (NGN) has been reported to have anti-AAA effects. However, water solubility and in vivo absorption of NGN are not satisfactory, which leads to its low bioavailability, thus affecting its pharmacological effects. In this project, the improving effects of isonicotinamide (INT) co-crystal and hydroxy propyl methyl cellulose (HPMC) or polyvinyl pyrrolidone (PVP) on the solubility, in vivo absorption, and anti-AAA effects of NGN were evaluated. METHODS: In the current study, co-crystals of naringenin-isonicotinamide (NGN-INT) were prepared, and effects of PVP or HPMC on precipitation rate, supersaturation, and bioavailability of NGN were explored. In addition, with or without HPMC supply, the effects of NGN-INT co-crystal on anti-AAA efficacy of NGN were investigated on an elastase-induced AAA mouse model, and the results were compared with the efficacy of the NGN crude drug. RESULTS: Our results demonstrate that NGN-INT formulation, compared to the NGN crude drug, enhanced the dissolution rate of NGN and significantly increased Cmax and AUC(0-∞) of NGN by 18 times and 1.97 times, respectively. Addition of PVP or HPMC in NGN-INT co-crystal further increased bioavailability of NGN in NGN-INT. The in vivo pharmacodynamic study showed that NGN-INT with HPMC significantly improved the inhibitory effects of NGN against AAA. CONCLUSION: NGN-INT significantly improved the absorption and aortic protective effects of NGN. The supersaturation-prolonging effect of HPMC further enhanced bioavailability and anti-AAA effects of NGN-INT.

8.
Zhongguo Zhong Yao Za Zhi ; 46(16): 4103-4110, 2021 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-34467720

RESUMO

In this study, the colonization, diversity and relative abundance of arbuscular mycorrhizal fungi(AMF) in the roots of Panax quinquefolius in different habitats of Shandong province were analyzed by staining-microscopy and high-throughput sequencing. The data were analyzed by bioinformatics tools and statistical software. The results showed that the roots of P. quinquefolius in different habitats were colonized by AMF with different rates and intensities. The AMF in roots of P. quinquefolius belong to three genera, three families, three orders, one class and one phylum. At the level of order, the AMF mainly included Paraglomerales(52.48%), Glomerales(25.60%) and Archaeosporales(3.08%). At the level of family, the AMF were dominated by Paraglomeraceae(52.48%), Glomeraceae(18.94%) and Claroideoglomeraceae(3.05%). At the level of genus, Paraglomus(51.46%), Glomus(20.01%) and Claroideoglomus(3.52%) accounted for a large proportion, of which Paraglomus and Glomus were dominant. Cluster analysis showed that the AMF in roots of P. quinquefolius with close geographical locations could be clustered together. In this study, the diversity and dominant germplasm resources of AMF in roots of P. quinquefolius cultivated in the main producing areas were identified, which provi-ded basic data for revealing the quality formation mechanism of P. quinquefolius medicinal materials from the perspective of environment.


Assuntos
Glomeromycota , Micorrizas , Panax , Fungos , Humanos , Micorrizas/genética , Raízes de Plantas , Microbiologia do Solo
9.
Adv Mater ; 33(42): e2103383, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34468056

RESUMO

Ultrathin 2D metal nanostructures have sparked a lot of research interest because of their improved electrocatalytic properties for fuel cells. So far, no effective technique for preparing ultrathin 2D Pd-based metal nanostructures with more than three compositions has been published. Herein, a new visible-light-induced template technique for producing PdAuBiTe alloyed 2D ultrathin nanosheets is developed. The mass activity of the PdAuBiTe nanosheets against the oxygen reduction reaction (ORR) is 2.48 A mgPd -1 , which is 27.5/17.7 times that of industrial Pd/C/Pt/C, respectively. After 10 000 potential cyclings, there is no decrease in ORR activity. The PdAuBiTe nanosheets exhibit high methanol tolerance and in situ anti-CO poisoning properties. The PdAuBiTe nanosheets, as cathode electrocatalysts in direct methanol fuel cells, can thus give significant improvement in terms of power density and durability. In O2 /air, the power density can be increased to 235.7/173.5 mW cm-2 , higher than that reported in previous work, and which is 2.32/3.59 times higher than Pt/C.

10.
Acta Pharm Sin B ; 11(9): 2924-2936, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34589405

RESUMO

Solid tumors always exhibit local hypoxia, resulting in the high metastasis and inertness to chemotherapy. Reconstruction of hypoxic tumor microenvironment (TME) is considered a potential therapy compared to directly killing tumor cells. However, the insufficient oxygen delivery to deep tumor and the confronting "Warburg effect" compromise the efficacy of hypoxia alleviation. Herein, we construct a cascade enzyme-powered nanomotor (NM-si), which can simultaneously provide sufficient oxygen in deep tumor and inhibit the aerobic glycolysis to potentiate anti-metastasis in chemotherapy. Catalase (Cat) and glucose oxidase (GOx) are co-adsorbed on our previously reported CAuNCs@HA to form self-propelled nanomotor (NM), with hexokinase-2 (HK-2) siRNA further condensed (NM-si). The persistent production of oxygen bubbles from the cascade enzymatic reaction propels NM-si to move forward autonomously and in a controllable direction along H2O2 gradient towards deep tumor, with hypoxia successfully alleviated in the meantime. The autonomous movement also facilitates NM-si with lysosome escaping for efficient HK-2 knockdown to inhibit glycolysis. In vivo results demonstrated a promising anti-metastasis effect of commercially available albumin-bound paclitaxel (PTX@HSA) after pre-treated with NM-si for TME reconstruction. This cascade enzyme-powered nanomotor provides a potential prospect in reversing the hypoxic TME and metabolic pathway for reinforced anti-metastasis of chemotherapy.

11.
J Virol Methods ; 297: 114263, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34391804

RESUMO

The novel goose astrovirus (GoAstV) is an emerging pathogenic virus that has resulted in large economic losses to the goose-rearing industry in China since 2016. The novel goose astrovirus cause gout in goslings with a mortality rate of around 50 %. Therefore, an effective diagnostic approach to monitor the spread of GoAstV is necessary. Here, a novel diagnostic immunochromatographic strip (ICS) assay was developed to detect GoAstV. A rapid immunochromatographic assay based on antibody colloidal gold nanoparticles specific to GoAstV was developed for the detection of GoAstV in goose allantoic fluid and supernatant of tissue homogenate. Monoclonal antibodies (Mabs) were prepared using the hybridoma technology, and the polyclonal antibodies (Pabs) were generated by immunizing the rabbits with recombinant ORF2 protein. In addition, the colloidal gold was prepared by reducing gold salt with sodium citrate coupled with Mabs against GoAstV. The optimal concentrations of the coating antibody and the capture antibody were examined as 1.6 mg/mL and 6 µg/mL. The optimal pH of the colloidal gold labeling was pH 8.0. With the visual observation, the lower limit of the ICS was reported to be approximately 1.2 µg/mL. Common diseases of goose were examined to assess the specificity of the ICS, and no cross-reaction was identified. 40 clinical positive samples were simultaneously detected by using the ICS and the PCR with a 92.5% coincidence rate between them. Furthermore, the mentioned samples could be stored at 25 °C and 4 °C for 4 and 6 months, respectively. It was proved that the ICS in this study was highly specific, sensitive, repeatable and more convenient to rapidly detect GoAstV in clinical samples.

12.
J Vet Med Sci ; 83(10): 1593-1596, 2021 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-34456197

RESUMO

Clostridium perfringens is an important zoonotic pathogen. This study was designed to explore the prevalence and toxin types of C. perfringens in retail beef collected from Beijing, China. Among 221 beef samples collected, 53 samples were positive for C. perfringens, resulting in the average prevalence as 23.98%. By toxin gene-based typing, the most C. perfringens strains belong to type A (96.23%, 51/53), only 2 strains were identified as type D. By a multi-locus sequence typing (MLST)-based analysis, a total of 36 sequence types (STs) were detected, and the most STs (n=30) represented just a single strain. These finding suggested that the prevalence of C. perfringens in retail beef in Beijing was considerably high and these bacteria displayed extreme diversity in genetics.


Assuntos
Doenças dos Bovinos , Infecções por Clostridium , Animais , Pequim , Bovinos , China/epidemiologia , Infecções por Clostridium/epidemiologia , Infecções por Clostridium/veterinária , Clostridium perfringens/genética , Tipagem de Sequências Multilocus/veterinária
13.
Front Nutr ; 8: 636930, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34124117

RESUMO

Fucoidan is a multifunctional marine carbohydrate polymer that differs in its chemical composition and bioactivity both between seaweed species and within species from different locations across the globe. In this study, fucoidan was extracted from the sporophyll of Undaria pinnatifida grown in Weihai, Shandong Province, China. Fucoidan fractions with molecular weight cutoffs (MWCO) of >300 kDa and <10 kDa were obtained via dialysis. The fucoidan standard from Sigma (Fstd, ≥95, CAS: 9072-19-9), fucoidan crude extract (WH), >300 kDa fraction (300k) and <10 kDa fraction (10k) were compared in terms of chemical composition and antioxidant capacity. Based on Fourier transform infrared spectroscopy (FT-IR) analysis, Fstd, WH, and 300k all showed strong bands around 830 cm-1, corresponding to the sulfate substituent in the molecule. The results showed that compared with WH and 300 k, the degree of sulfation at 10k was the lowest. From Nuclear magnetic resonance spectroscopy (NMR) result, the four fucoidan samples all contain α-L-fucose. The primary antioxidant ability of the 10k is significantly higher than that of the 300k, WH, and Fstd, but the secondary antioxidant capabilities of the 10k and 300k were similar, and both were higher than that of the butylated hydroxyanisole (BHA). The ferric reducing antioxidant ability was higher in the 300k and WH fractions. This demonstrates that fucoidan extracted from U. pinnatifida grown in Weihai, China should be a useful nutraceutical resource.

14.
Zhongguo Zhong Yao Za Zhi ; 46(10): 2461-2466, 2021 May.
Artigo em Chinês | MEDLINE | ID: mdl-34047091

RESUMO

Biochar is a kind of solid material with high aromatization and rich in carbon, which is formed by pyrolysis of biomass at high temperature(250-700 ℃) under anoxic or hypoxic conditions. It has the characteristics of large specific surface area and rich pores. In recent years, as a good soil conditioner, biochar has gradually improved its advantages in improving soil rhizosphere micro ecological environment, promoting plant growth and development, and enhancing plant resistance, etc. It has been proved that biochar can affect the growth and development of plants by improving soil physical and chemical properties, adjusting microbial community structure, participating in the metabolic process in plants, and inducing plants to enhance resistance. This paper summarized the research progress of biochar application in agriculture and introduced the ecological effects and mechanism of biochar on plant seed germination, seedling growth, crop yield and stress resistance. Combined with the characteristics of Chinese materia medica, this paper expounds the application potential of biochar in improving the content of secondary metabolites of Chinese materia medica and alleviating continuous cropping obstacles of Chinese materia medica, etc. In the future, it is necessary to strengthen the research of biochar in the biosynthesis of secondary metabolites, allelopathy and heavy metal stress of medicinal plants, so as to provide reference for the application of biochar in the cultivation of Chinese materia medica.


Assuntos
Medicamentos de Ervas Chinesas , Materia Medica , Agricultura , Carvão Vegetal , China , Humanos
15.
Int J Pharm ; 604: 120749, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-34051319

RESUMO

In recent years, transdermal preparations have emerged as one of the most promising modes of administration. In particular, dissolving microneedles have attracted extensive attention because of their painlessness, safety, high delivery efficiency and easily operation for patients. This article mainly reviews the preparation methods, the types of matrix polymer materials, the content of dissolving microneedles performance testing, and the applications of dissolving microneedles. It is expected to lay a solid knowledge foundation for the in-depth study of the dissolving microneedles.


Assuntos
Agulhas , Preparações Farmacêuticas , Administração Cutânea , Sistemas de Liberação de Medicamentos , Humanos , Microinjeções , Polímeros
16.
Hum Vaccin Immunother ; 17(9): 3145-3152, 2021 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-33847247

RESUMO

Background: Lincang City in Yunnan Province on the China-Myanmar border, has reached the World Health Organization recommended coverage (95%) for measles-containing vaccine (MCV), but measles outbreaks still occur. We conducted a survey in Lincang City to determine the measles vaccination status of children on the China-Myanmar border.Methods: We used multistage sampling among children aged 8-83 months. Information on measles vaccination status was obtained from the child's vaccination certificate, and serum samples were tested using commercially available ELISA kits.Results: A total of 938 children were surveyed. The vaccination coverage rate was 98.9% (95% CI: 98.2-99.6%) for measles-containing vaccine dose 1 (MCV1), and 95.8% (95% CI:94.9-96.7%) for measles-containing vaccine dose 2 (MCV2). The timely vaccination coverage rate was 52.0% (95% CI:48.8-55.2%) for MCV1, and 74.1% (95% CI: 82.9-89.0%) for MCV2. The timely-and-complete vaccination coverage rate was 41.0% (95% CI: 36.7-45.3%). The median delay period was 33 (95% CI: 27-39) days for MCV1, and 196 (95% CI: 146-246) days for MCV2. The seropositivity rate in children aged less than 7 years was 94.0% (95% CI: 92.5-95.5%) with a geometric mean titer of 1210.1 mIU/mL.Conclusions: The MCV coverage was high, but timely and timely-and-complete vaccination coverage were low and insufficient to prevent measles outbreaks. It is necessary to add the timely and timely-and-complete vaccination coverage as indicators of vaccination to provide a more complete picture of measles immunization status.


Assuntos
Sarampo , Cobertura Vacinal , Criança , China/epidemiologia , Humanos , Programas de Imunização , Lactente , Sarampo/prevenção & controle , Vacina contra Sarampo , Inquéritos e Questionários , Vacinação
17.
Int Arch Allergy Immunol ; 182(9): 852-862, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33895737

RESUMO

The prevalence of food allergy (FA) is increasing, and there is an urgent need to take effective measures against it. One important measure is the avoidance diet, which shows a disadvantage, especially in case of accidental exposure. Oral tolerance restoration sheds new light on the control of FA. Oral tolerance is naturally a state of systemic unresponsiveness of the gastrointestinal tract to food antigens and its restoration can be a clinical therapy for FA. Its immune basis lies on the intestinal mucosal immune system and factors, such as gut microbiota and food processing methods, are also important. This review presents recent advances in oral tolerance and its closely related factors.


Assuntos
Alérgenos/imunologia , Dessensibilização Imunológica , Hipersensibilidade Alimentar/imunologia , Hipersensibilidade Alimentar/terapia , Tolerância Imunológica , Administração Oral , Alérgenos/administração & dosagem , Animais , Dessensibilização Imunológica/métodos , Hipersensibilidade Alimentar/diagnóstico , Humanos , Imunidade nas Mucosas , Mucosa Intestinal/imunologia , Linfócitos T/imunologia , Linfócitos T/metabolismo
18.
Sci Rep ; 11(1): 8030, 2021 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-33850191

RESUMO

Mutagenicity exerts adverse effects on humans. Conventional methods cannot simultaneously predict the toxicity of a large number of compounds. Most mutagenicity prediction models are based on a single experimental type and lack other experimental combination data as support, resulting in limited application scope and predictive ability. In this study, we partitioned data from GENE-TOX, CPDB, and Chemical Carcinogenesis Research Information System according to the weight-of-evidence method for modelling. In our data set, in vivo and in vitro experiments in groups as well as prokaryotic and eukaryotic cell experiments were included in accordance with the ICH guideline. We compared the two experimental combinations mentioned in the weight-of-evidence method and reintegrated the experimental data into three groups. Nine sub-models and three fusion models were established using random forest (RF), support vector machine (SVM), and back propagation (BP) neural network algorithms. When fusing base models under the same algorithm according to the ensemble rules, all models showed excellent predictive performance. The RF, SVM, and BP fusion models reached a prediction accuracy rate of 83.4%, 80.5%, 79.0% respectively. The area under the curve (AUC) reached 0.853, 0.897, 0.865 respectively. Therefore, the established fusion QSAR models can serve as an early warning system for mutagenicity of compounds.

19.
J Inorg Biochem ; 220: 111458, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33857697

RESUMO

There has been growing interest in the application of gold nanorods (GNRs) to tumor therapy due to the unique properties they possess. In the past, GNRs were not used in clinical treatments as they lacked stability in vivo and were characterized by potential toxicity. Despite these issues, the significant potential for utilizing GNRs to conduct safe and effective treatments for tumors cannot be ignored. Therefore, it remains crucial to thoroughly investigate the mechanisms behind the toxicity of GNRs in order to provide the means of overcoming obstacles to its full application in the future. This review presents the toxic effects of GNRs, the factors affecting toxicity and the methods to improve biocompatibility, all of which are presently being studied. Finally, we conclude by briefly discussing the current research status of GNRs and provide additional perspective on the challenges involved along with the course of development for GNRs in the future.

20.
Quant Imaging Med Surg ; 11(2): 676-684, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33532267

RESUMO

Background: This study aimed to use the stretched-exponential nonlinear regression analysis model to explore the value of the energy spectral curve in the differential diagnosis of clear cell renal cell carcinoma (ccRCC), minimal fat renal angiomyolipoma (RAML), and hypovascular renal cell carcinoma. Methods: Sixty-five cases with renal tumors were enrolled retrospectively who had undergone a preoperative multiphase spectral CT scan of the kidney in pre-enhance and double-phase enhanced scanning. The normalized iodine concentrations (NIC) of these lesions, normal renal cortex, and psoas major were measured and calculated. The spectral curves of these lesions and normal tissues were analyzed to calculate the stretched-exponential index (α) and b value with the stretched-exponential nonlinear regression analysis model (y=-b·Xα). The differences between α, b value, and NIC of these lesions and normal tissues in pre-enhance and two enhanced phases were compared using one-way ANOVA. The correlation between α, b value, and NIC was evaluated using the Pearson coefficient test, with significance assigned at the 5% level. Results: There was no significant difference in α value between the groups in pre-enhance scanning. In the Cortical phase (CP), there were no significant differences in NIC and α value between minimal fat RAML and hypovascular renal cell carcinoma, or between ccRCC and the normal renal cortex. However, in the nephrographic phase (NP), a significant difference in α value was found between minimal fat RAML and hypovascular renal cell carcinoma, but no difference in NIC between them. In NP, there were significant differences in NIC and α values between ccRCC and the normal renal cortex. In CP and NP, there were significant differences between the psoas major and other groups in all parameters. For b value, in pre-enhance scanning, there was a significant difference between the psoas major and other groups, and between ccRCC and the normal renal cortex. There was no significant difference between other groups. After enhancement, in CP and NP, significant differences were observed between the psoas major and other groups in b value, but no significant differences were observed between all renal tumors and the normal renal cortex. A linear correlation was found between α values and NIC in CP (r=0.780, P=0.00) and NP (r=0.693, P=0.00). The b values and NIC had a low correlation in CP, with no correlation in NP. Conclusions: Quantitative spectral CT with the stretched-exponential nonlinear regression analysis model may enhance the differential diagnosis ability for renal tumors. Its clinical value remains to be further explored in other types of soft tissue lesions.

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