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1.
Clin Pharmacol Drug Dev ; 11(2): 165-172, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34453416

RESUMO

Tadalafil is an effective, reversible, and competitive phosphodiesterase 5 inhibitor mainly used to treat erectile dysfunction. This study investigated the bioequivalence of generic and marketed formulations of 10-mg tadalafil tablets under fasted and fed conditions. This open-label, randomized, single-dose, 2-period crossover study included 53 healthy Chinese men (aged 20-43 years). Plasma samples were collected from 0.5 hours before treatment to 72 hours after each dose and analyzed using ultra-high-performance liquid chromatography coupled with tandem mass spectrometry. Pharmacokinetic parameters were calculated using noncompartmental analysis. Safety assessments were performed throughout the study. For the fasted state, the 90% confidence intervals of the geometric mean ratios between the generic and marketed formulations were 86.1% to 99.1% for the maximum plasma concentration and 88.4% to 100.3% for the area under the plasma concentration-time curve from time 0 to infinity, and the corresponding values under the fed state were and 99.9% to 108.4% and 95.7% to 104.3%, respectively. All data were within the accepted bioequivalence range of 80% to 125%. After consuming high-fat, high-calorie meals in the fed condition, the time to the maximum plasma concentration was similar between the formulations, and area under the plasma concentration-time curve from time 0 to infinity and maximum plasma concentration were 10.2% and 6.55% higher, respectively, for the marketed formulation. Thus, food had no clinically relevant effect on tadalafil exposure following a single oral dose in healthy Chinese men. No serious adverse reactions were reported. These results indicated that the analyzed generic and marketed tadalafil tablets were bioequivalent with similar safety profiles.


Assuntos
Jejum , Adulto , China , Estudos Cross-Over , Humanos , Masculino , Comprimidos , Tadalafila/efeitos adversos , Equivalência Terapêutica , Adulto Jovem
2.
Comput Intell Neurosci ; 2022: 2459996, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35510062

RESUMO

With the rapid development of science and technology, testing equipment and testing methods are constantly updated. Radar detectors have the advantages of losslessness, high efficiency, high resolution, and high-speed radar image capture. They can accurately locate defects in railway tunnels, respond to hidden dangers in time, and provide strong technical support for transportation. This paper proposes to optimize the defect detection of railway tunnel radar through the combination of multisensor technology and active interference suppression algorithm and designs the corresponding sensor system according to the content. This article analyzes several factors that affect the radar detection effect and makes a detailed summary from the detection environment and other aspects. At the same time, it uses the multisensor system combined with active interference suppression algorithm to design a railway tunnel detection simulation experiment. Experimental results show that the use of multisensors combined with active interference suppression algorithm to optimize radar detection can effectively improve the accuracy of railway tunnel defect detection. Through the analysis of the results of tunnel defect detection, the detection accuracy of this paper has reached 98.8%, which can provide an effective reference for the detection of railway tunnels.

3.
J Gastrointest Oncol ; 13(2): 559-568, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35557584

RESUMO

Background: Gastric cancer is one of the most lethal cancers. Aberrant expression levels of genes are frequently associated with cell immortalization and the occurrence of tumors. In this study, we aimed to investigate the role of tankyrase 1 (TANK1) in gastric adenocarcinoma and clarify the underlying mechanism. Methods: The messenger RNA (mRNA) levels of TANK1, human telomerase reverse transcriptase (h-TERT), and telomeric repeat binding factor 1 (TRF1) in clinical specimens and SGC-7901 cells were measured via real-time quantitative polymerase chain reaction (RT-qPCR). Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) and immunohistochemistry (IHC) assays were utilized to observe the cell apoptosis as well as Ki67 and h-TERT expression in tumor-bearing models. The effects of TANK1 antisense oligonucleotides (TANK1 ASODN) on viability and apoptosis of SGC 7901 cells were evaluated by cell counting kit-8 and flow cytometry analysis. Results: We found that TANK1 and h-TERT were both increased in gastric adenocarcinoma, while TRF1 was decreased. Tumor-bearing models demonstrated that TANK1 ASODN appeared to be effective in inhibiting tumor growth and decreasing the expression of h-TERT. Additionally, TANK1 ASODN inhibited the viability and promoted apoptosis of SGC-7901 cells. Moreover, the mRNA levels of h-TERT and TRF1 were modulated by TANK1 ASODN. Conclusions: This study revealed that TANK1 ASODN inhibits the proliferation and induced the apoptosis of gastric adenocarcinoma cells via manipulating the expression levels of h-TERT and TRF1.

4.
Colloids Surf B Biointerfaces ; 216: 112529, 2022 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-35561636

RESUMO

Resveratrol is a well-studied dietary polyphenol with diverse health-promoting bioactivities. However, the aqueous insolubility and chemical instability of resveratrol hamper its practical application. This study set out to address these limitations by constructing zein-fucoidan composite nanoparticles as a delivery system of resveratrol. The optimized resveratrol-loaded zein-fucoidan particles (RE-ZFP) were obtained at zein-to-fucoidan ratio of 2:1 (w/w) and zein-to-resveratrol ratio of 10:1 (w/w), and RE-ZFP showed evenly distributed and smoothly spherical microstructures, mean particle size of 121 nm, ζ-potential of - 41 mV, encapsulation efficiency for resveratrol of 95.4%. Electrostatic, steric, hydrophobic, and hydrogen-bonding interactions were major forces required to form RE-ZFP. In addition, RE-ZFP exhibited greater photostability and colloidal stability (including pH, ionic, and storage stabilities) than resveratrol-loaded zein particles (RE-ZP). Particularly, RE-ZFP showed fairly good pH stability. Moreover, zein-fucoidan-based delivery system exhibited a controlled release of resveratrol under in vitro digestion. Finally, zein-fucoidan nanocarriers presented extremely low cytotoxicity to HIEC-6 cells. All the findings demonstrate that the zein-fucoidan nanoparticles developed in the current work will be a prospective strategy for loading resveratrol and other hydrophobic bioactive ingredients and thus extending their application in nutraceuticals or pharmaceuticals.

5.
BMC Musculoskelet Disord ; 23(1): 462, 2022 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-35578221

RESUMO

BACKGROUND: Conservative treatment is the recommended first-line treatment for degenerative disc diseases. Traction therapy has historically been one of the most common clinical methods to address this, but the clinical effect remains controversial. METHODS: Forty-two six-month-old male Sprague-Dawley rats were randomly divided into six groups: the model group (Group A, four coccyx vertebrae (Co7-Co10) were fixed with customized external fixators, and the vertebral disc degeneration model was constructed by axial compression of the target segment Co8 - Co9 for 4 weeks), the experimental control group (Group B, after successful modeling, the external fixation device was removed and self-rehabilitation was performed) and four intervention groups (Groups C to F): Groups C and E: Co8 - Co9 vertebrae compressed for 4 weeks followed by two or 4 weeks of high tension traction (HTT), respectively, and Groups D and F: vertebrae compressed for 4 weeks followed by two or 4 weeks of low-tension traction (LTT), respectively. Imaging tests (X-ray and MRI) were performed to assess disc height and T2 signal intensity at each time point. After the experiment, the animals were euthanized, and the caudal vertebrae were collected for analysis of intervertebral disc histopathology, proteoglycan content, and micronanostructure of the annulus fibrosus, nucleus pulposus and bony endplate. RESULTS: Signs of tissue regeneration were apparent in all four intervention groups. After two to 4 weeks of intervention (HTT and LTT), the morphology of pores in the bony endplate, their number, and diameter had recovered significantly compared with those in Group A. The LTT group was superior to the HTT group, and the 4w in situ group was significantly superior to the 2w group. Meanwhile, the histological scores of discs, the mean fibril diameter and modulus of annulus fibrosus were significantly improved compared with the control groups, and the LTT group was superior to HTT group. CONCLUSIONS: Low-tension traction better promotes active reconstruction of bony endplates and improves the elastic modulus and micro/nanostructure of the disc. Thus, it further promotes the regeneration and repair of intervertebral discs.

6.
Anal Cell Pathol (Amst) ; 2022: 2721005, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35509814

RESUMO

Clear cell renal cell carcinoma (ccRCC) is the most common histological and devastating subtype of renal cell carcinoma. Necroptosis is a form of programmed cell death that causes prominent inflammatory responses. miRNAs play a significant role in cancer progression through necroptosis. However, the prognostic value of necroptosis-related miRNAs remains ambiguous. In this study, 39 necroptosis-related miRNAs (NRMs) were extracted and 17 differentially expressed NRMs between normal and tumor samples were identified using data form The Cancer Genome Atlas (TCGA). After applying univariate Cox proportional hazard regression analysis and LASSO Cox regression model, six necroptosis-related miRNA signatures were identified in the training cohort and their expression levels were verified by qRT-PCR. Using the expression levels of these miRNAs, all patients were divided into the high- and low-risk groups. Patients in the high-risk group showed poor overall survival (P < 0.0001). Time-dependent ROC curves confirmed the good performance of our signature. The results were verified in the testing cohort and the entire TCGA cohort. Univariate and multivariate Cox regression models demonstrated that the risk score was an independent prognostic factor. Additionally, a predictive nomogram with good performance was constructed to enhance the implementation of the constructed signature in a clinical setting. We then employed miRBD, miRTarBase, and TargetScan to predict the target genes of six necroptosis-related miRNAs. Gene ontology and Kyoto Encyclopedia of Genes and Genomes analyses indicated that 392 potential target genes were enriched in cell proliferation-related biological processes. Six miRNAs and 59 differentially expressed target genes were used to construct an miRNA-mRNA interaction network, and 11 hub genes were selected for survival and tumor infiltration analysis. Drug sensitivity analysis revealed potential drugs that may contribute to cancer management. Hence, necroptosis-related genes play an important role in cancer biology. We developed, for the first time, a necroptosis-related miRNA signature to predict ccRCC prognosis.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , MicroRNAs , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/metabolismo , Feminino , Humanos , Neoplasias Renais/genética , Neoplasias Renais/patologia , Masculino , MicroRNAs/genética , MicroRNAs/metabolismo , Necroptose/genética
7.
Artigo em Inglês | MEDLINE | ID: mdl-35532208

RESUMO

Xenogeneic sources of collagen type I remain a common choice for regenerative medicine applications due to ease of availability. Human and animal sources have some similarities, but small variations in amino acid composition can influence the physical properties of collagen, cellular response, and tissue remodeling. The goal of this work is to compare human collagen type I-based hydrogels versus animal-derived collagen type I-based hydrogels, generated from commercially available products, for their physico-chemical properties and for tissue engineering and regenerative medicine applications. Specifically, we evaluated whether the native human skin type I collagen could be used in the three most common research applications of this protein: as a substrate for attachment and proliferation of conventional 2D cell culture; as a source of matrix for a 3D cell culture; and as a source of matrix for tissue engineering. Results showed that species and tissue specific variations of collagen sources significantly impact the physical, chemical, and biological properties of collagen hydrogels including gelation kinetics, swelling ratio, collagen fiber morphology, compressive modulus, stability, and metabolic activity of hMSCs. Tumor constructs formulated with human skin collagen showed a differential response to chemotherapy agents compared to rat tail collagen. Human skin collagen performed comparably to rat tail collagen and enabled assembly of perfused human vessels in vivo. Despite differences in collagen manufacturing methods and supplied forms, the results suggest that commercially available human collagen can be used in lieu of xenogeneic sources to create functional scaffolds, but not all sources of human collagen behave similarly. These factors must be considered in the development of 3D tissues for drug screening and regenerative medicine applications.

8.
RSC Adv ; 12(14): 8611-8616, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35424794

RESUMO

We herein report a novel dibenzo[a,c]phenazine-based fluorescent probe with fast response to thiophenols over a wide pH range from 5 to 13. The probe possesses a large Stokes shift (120 nm). More importantly, it displays a high selectivity and sensitivity for thiophenols in the presence of other analytes such as biothiols and common metal ions. A good linear relationship between the fluorescence intensity at 570 nm and the thiophenol concentration in the range of 0-20 µM was observed with a low detection limit at 40 nM. In addition, it has been successfully applied to detect thiophenols in environmental water (such as seawater, tap water and spring water) with high recovery, which confirmed its potential value in environmental monitoring.

9.
J Healthc Eng ; 2022: 1795588, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35463671

RESUMO

Objective: The study aimed to use machine learning algorithms to predict the need for revascularization in patients presenting with chest pain in the emergency department. Methods: We obtained data from 581 patients with chest pain, 264 who underwent revascularization, and the other 317 were treated with medication alone for 3 months. Using standard algorithms, linear discriminant analysis, and standard algorithms, we analyzed 41 features relevant to coronary artery disease (CAD). Results: We identified seven robust predictive features. The combination of these predictors gave an area under the curve (AUC) of 0.830 to predict the need for revascularization. By contrast, the GRACE score gave an AUC of 0.68. Conclusions: This machine learning-based approach predicts the need for revascularization in patients with chest pain.


Assuntos
Dor no Peito , Doença da Artéria Coronariana , Doença da Artéria Coronariana/cirurgia , Serviço Hospitalar de Emergência , Humanos , Aprendizado de Máquina , Valor Preditivo dos Testes , Medição de Risco
10.
J Healthc Eng ; 2022: 5732357, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35368947

RESUMO

Acute abdomen is a clinical emergency disease with acute abdominal pain as the main prominent feature. Through severe disease changes in intra-abdominal, extrapelvic, and retroperitoneal tissues and organs, symptoms and clinical signs led by abdominal pain are formed. This article mainly explores the role of CT imaging diagnosis in common acute abdominal diseases in general surgery. In this paper, the use of computer-aided CT scan imaging technology in pulmonary nodules was firstly investigated, and the image segmentation algorithms based on CT images were given, including the spatial domain fuzzy C-mean clustering separation algorithm and the spatial domain fuzzy clustering level set semiautomatic separation algorithm, then the treatment of acute abdomen under the concept of ERAS was explored, and the treatment of ERAS under CT images of the acute abdomen was analyzed and studied. The empirical research results show that the ERAS's concept is guided by the undergoing national nutritional support with the traditional perioperative management. Compared to 12.9% of complications in traditional CPM groups, the recall rate of complications after ERAS group was only 6.01%, the improvement was obvious and the results were statistically significant (P < 0.05). Postoperative hospitalization time was also 4.62 days from 7.93 days, thus controlling the clinical risks of perioperative periods, providing a benefit to patient life.


Assuntos
Algoritmos , Tomografia Computadorizada por Raios X , Análise por Conglomerados , Humanos , Tomografia Computadorizada por Raios X/métodos
11.
Cell Death Dis ; 13(4): 352, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35428760

RESUMO

Androgen receptor (AR) signaling drives prostate cancer (PC) progression. Androgen deprivation therapy (ADT) is temporally effective, whereas drug resistance inevitably develops. Abnormal expression of AR/ARV7 (the most common AR splicing variant) is critical for endocrine resistance, while the detailed mechanism is still elusive. In this study, bioinformatics and immunohistochemical analyses demonstrate that RNF8 is high expressed in PC and castration-resistant PC (CRPC) samples and the expression of RNF8 is positively correlated with the Gleason score. The high expression of RNF8 in PCs predicts a poor prognosis. These results provide a potential function of RNF8 in PC progression. Furthermore, the mRNA expression of RNF8 is positively correlated with that of AR in PC. Mechanistically, we find that RNF8 upregulates c-Myc-induced AR transcription via altering histone modifications at the c-Myc binding site within the AR gene. RNF8 also acts as a co-activator of AR, promoting the recruitment of AR/ARV7 to the KLK3 (PSA) promoter, where RNF8 modulates histone modifications. These functions of RNF8 are dependent on its E3 ligase activity. RNF8 knockdown further reduces AR transactivation and PSA expression in CRPC cells with enzalutamide treatment. RNF8 depletion restrains cell proliferation and alleviates enzalutamide resistance in CRPC cells. Our findings indicate that RNF8 may be a potential therapeutic target for endocrine resistance in PC.


Assuntos
Proteínas de Ligação a DNA , Neoplasias de Próstata Resistentes à Castração , Receptores Androgênicos , Ubiquitina-Proteína Ligases , Antagonistas de Androgênios/uso terapêutico , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Progressão da Doença , Humanos , Calicreínas/genética , Calicreínas/metabolismo , Masculino , Antígeno Prostático Específico/genética , Antígeno Prostático Específico/metabolismo , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/genética , Neoplasias de Próstata Resistentes à Castração/metabolismo , Neoplasias de Próstata Resistentes à Castração/patologia , Isoformas de Proteínas , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Regulação para Cima
12.
Nat Commun ; 13(1): 2316, 2022 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-35484125

RESUMO

Understanding the hybrid charge-storage mechanisms of pseudocapacitive nanomaterials holds promising keys to further improve the performance of energy storage devices. Based on the dependence of the light scattering intensity of single Prussian blue nanoparticles (PBNPs) on their oxidation state during sinusoidal potential modulation at varying frequencies, we present an electro-optical microscopic imaging approach to optically acquire the Faradaic electrochemical impedance spectroscopy (oEIS) of single PBNPs. Here we reveal typical pseudocapacitive behavior with hybrid charge-storage mechanisms depending on the modulation frequency. In the low-frequency range, the optical amplitude is inversely proportional to the square root of the frequency (∆I ∝ f-0.5; diffusion-limited process), while in the high-frequency range, it is inversely proportional to the frequency (∆I ∝ f-1; surface charging process). Because the geometry of single cuboid-shaped PBNPs can be precisely determined by scanning electron microscopy and atomic force microscopy, oEIS of single PBNPs allows the determination of the depth of the surface charging layer, revealing it to be ~2 unit cells regardless of the nanoparticle size.

13.
Aesthetic Plast Surg ; 2022 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-35441847

RESUMO

BACKGROUND: As periorbital aesthetic commonly improved in blepharoptosis patients after correction surgery, the aim of this study was to elaborate the brow-eyelid continuum changes in moderate-severe ptosis patients who underwent conjoint fascial sheath suspension systematically. METHODS: Patients with moderate-severe ptosis who underwent conjoint fascial sheath suspension were assessed by using pre- and post-operative digital photographs in the primary gaze position of the eye. The main outcome measurements included marginal reflex distance1 (MRD1), palpebral fissure height (PFH), eyebrow position, the symmetry of face and the horizontal forehead lines condition. RESULTS: There were 43 patients (53 eyelids) in our study, including 33 unilateral and 10 bilateral patients. The mean levator function was 3.00 ± 1.07 mm. Before surgery, the mean MRD1 and PFH were 0.60 ± 1.14 mm and 6.75 ± 1.71 mm, respectively. The mean eyebrow height at medial, center, lateral position was 33.16 ± 3.95 mm, 35.99 ± 4.02 mm and 34.35 ± 4.80 mm, respectively. It was found that MRD1 and PFH symmetry both were 23.26% and eyebrow symmetry was 62.79%. For forehead wrinkles, 48.84% of the patients was mild, 34.88% was moderate, and 16.28% was severe. The average follow-up was 12.78 months (ranged from 12 to 18 months). One month after surgery, the mean MRD1 and PFH were 5.68 ± 0.86 mm, 11.61 ± 0.97 mm, respectively, both of which improved significantly (P < 0.0001). The mean eyebrow height at medial, center, lateral position descended to 28.22 ± 4.77 mm (P = 0.017), 31.41 ± 4.58 mm (P = 0.033) and 30.28 ± 3.41 mm (P = 0.018), respectively. The result showed that the rate of patients with MRD1 symmetry was 32.56%, PFH symmetry was 30.23%, and eyebrow symmetry was 90.7%. For forehead wrinkles, 69.77% was mild and 30.23% was moderate. Then, patients' eyebrow gradually elevated, while their upper eyelid dropped. At the last follow-up, the mean MRD1 and PFH were 3.83 ± 0.98 mm and 9.84 ± 1.56 mm, respectively. The mean eyebrow height at medial, center, lateral position improved to 30.52 ± 4.59 mm (P = 0.031), 32.40 ± 4.68 mm (P = 0.033), 31.19 ± 4.16 mm (P = 0.028), respectively. The patients with MRD1 symmetry accounted for 86.05%, PFH symmetry 86.05%, and eyebrow symmetry 90.7%. For forehead wrinkles, 67.44% was mild and 32.56% was moderate. CONCLUSION: CFS suspension can effectively reconstruct moderate-severe ptosis patients' aesthetics of the brow-eyelid continuum by descending elevated eyebrow, improving facial symmetry and reducing forehead rhytids. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

14.
Front Pharmacol ; 13: 764305, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35401217

RESUMO

Background: To explore the effect of combining traditional Chinese medicine (TCM) and Western medicine in hemodialysis patients with coronavirus disease 2019 (COVID-19). Methods: This study was conducted from 27 January 2020 to 17 March 2020 in Wuhan Third Hospital Guanggu Branch, Wuhan, China. Fifty-three patients were included and divided into a control group (CG), which received Western medicine and a combined treatment group, which received TCM and Western medicine (TG). Clinical and laboratory data, TCM symptom scores, and chest computed tomography results were extracted and compared between the two groups. Results: The TG included 21 (67.7%) men and 10 (32.3%) women with a mean age of 61.02 (standard deviation [SD] 15.07, range 26-89) years. The mean dialysis duration in the TG was 49 (SD 31) months. Of all patients in the TG, 27 (87.1%) had fatigue, 18 (58.1%) had dry cough, 16 (51.6%) had anorexia, 11 (35.5%) had dyspnea, and 11 (35.5%) had fever. The CG included 14 (63.6%) men and 8 (36.4%) women with a mean age of 61.45 (SD 13.78, range 36-84) years. The mean dialysis duration in the CG was 63 (SD 46) months. Of all patients in the CG, 21 (95.5%) had fatigue, 12 (54.5%) had dry cough, 17 (77.3%) had anorexia, 12 (54.5%) had dyspnea, and 7 (31.8%) had fever. After treatment, the TCM symptom scores of the two groups decreased; the anorexia scores were lower in the TG than in the CG (p < 0.05). After treatment, albumin increased and D-dimer, C-reactive protein, and lactate dehydrogenase levels decreased in the TG. The d-dimer levels were lower and the albumin level was higher in the TG than in the CG after treatment (p < 0.05). The cure rate was higher, and the mortality rate was lower in the TG than in the CG (p < 0.05). Conclusion: A combination of TCM and Western medicine in hemodialysis patients with COVID-19 could relieve symptoms and help recovery. Further evidence from larger randomized controlled trials is needed to confirm our results.

15.
Org Lett ; 24(16): 3097-3101, 2022 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-35436115

RESUMO

We herein report regiodivergent ligand-controlled palladium-catalyzed asymmetric cycloaddition reactions between spirovinylcyclopropyl oxindoles and o-quinone methides. Specifically, by using the chiral P,P-ligand Segphos (L5), we obtained various spirooxindole-3,4-benzo[b]oxepanes in moderate to good yields with excellent enantioselectivities via [4+3] cycloaddition reactions. In contrast, reactions involving Trost's ligand (L7) showed different regio- and stereoselectivities, affording bispirooxindole heterocyclic compounds in good yields via [2+3] cycloaddition reactions.

17.
J Colloid Interface Sci ; 619: 388-398, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35398769

RESUMO

HYPOTHESIS: The practical applications of boron nitride nanosheet (BNNS) are dramatically limited by the harsh exfoliation and surface functionalization conditions due to the hydrophobic and chemically inert nature. This issue can be improved by selecting efficient modifiers with hydrophilic groups. EXPERIMENTS: A green and scalable amino acid-assisted ball milling method is presented to exfoliate and functionalize BNNS simultaneously. The different interactions between BNNS and four amino acids (tryptophan (Trp), phenylalanine (Phe), arginine (Arg), lysine (Lys)) are thoroughly investigated to rationalize the thermal and mechanical properties of their corresponding epoxy (EP) composites. FINDING: Trp and Phe display higher functionalization degree and dispersibility of BNNS than Arg and Lys thanks to the additional π-π interactions between the aromatic groups and BNNS. Moreover, both BNNS-Trp/EP and BNNS-Phe/EP exhibit higher cross-plane thermal conductivity of 2.1 and 1.96 W m-1 K-1 at 30 wt% filler loading. In addition, the mechanical strengths of all these amino acids functionalized BNNS filled epoxy composites are significantly enhanced due to stronger interfacial interactions between fillers and epoxy matrix. Thus, this work paves the way for the facile mass production of functionalized BNNS and expedites their applications in thermal interface materials of electronic components.


Assuntos
Aminoácidos , Compostos de Boro , Compostos de Boro/química , Resinas Epóxi , Condutividade Térmica
18.
Crit Rev Food Sci Nutr ; : 1-26, 2022 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-35317688

RESUMO

Airborne particulate matter (PM) exerts huge negative impacts on human health worldwide, not only targeting the respiratory system but more importantly inducing and aggravating associated chronic diseases like asthma, lung cancer, atherosclerosis, diabetes mellitus and Alzheimer diseases. Food-derived bioactive compounds like vitamins, dietary polyphenols, omega-3 polyunsaturated fatty acids and sulforaphane are feasible alternative therapeutic approaches against PM-mediated potential health damages, drawing great attention in recent years. In this review, the association between PM exposure and risks of developing chronic diseases, and the detailed mechanisms underlying the detrimental effects of PM will be discussed. Subsequently, principal food-derived bioactive compounds, with emphasize on the preventative or protective effects against PM, along with potential mechanisms will be elucidated. This comprehensive review will discuss and present current research findings to reveal the nutritional intervention as a preventative or therapeutic strategy against ambient air pollution, thereby lowering the risk of developing chronic diseases.

19.
Bone Res ; 10(1): 31, 2022 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-35301280

RESUMO

Osteoporosis caused by aging is characterized by reduced bone mass and accumulated adipocytes in the bone marrow cavity. How the balance between osteoblastogenesis and adipogenesis from bone marrow mesenchymal stem cells (BMSCs) is lost upon aging is still unclear. Here, we found that the RNA-binding protein Musashi2 (Msi2) regulates BMSC lineage commitment. Msi2 is commonly enriched in stem cells and tumor cells. We found that its expression was downregulated during adipogenic differentiation and upregulated during osteogenic differentiation of BMSCs. Msi2 knockout mice exhibited decreased bone mass with substantial accumulation of marrow adipocytes, similar to aging-induced osteoporosis. Depletion of Msi2 in BMSCs led to increased adipocyte commitment. Transcriptional profiling analysis revealed that Msi2 deficiency led to increased PPARγ signaling. RNA-interacting protein immunoprecipitation assays demonstrated that Msi2 could inhibit the translation of the key adipogenic factor Cebpα, thereby inhibiting PPAR signaling. Furthermore, the expression of Msi2 decreased significantly during the aging process of mice, indicating that decreased Msi2 function during aging contributes to abnormal accumulation of adipocytes in bone marrow and osteoporosis. Thus, our results provide a putative biochemical mechanism for aging-related osteoporosis, suggesting that modulating Msi2 function may benefit the treatment of bone aging.

20.
Eur J Radiol ; 150: 110240, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35290911

RESUMO

PURPOSE: The dual-energy computed tomography(CT) angiography can accurately display subtle details of blood vessels and their surroundings. We aimed to apply dual-energy CT angiography and virtual monochromatic spectral(VMS) images to pelvic mass imaging and evaluate its value of distinguishing between benign and malignant pelvic masses. METHODS: The prospective study was approved by the Institutional Review Board and all participants signed informed consent forms. From August 2018 to July 2020, consecutive female patients with pelvic mass undergone dual-source third-generation CT angiography. The 40 keV VMS images were reconstructed to display mass morphology and corresponding feeding arteries. All images were evaluated by two radiologists blinded to diagnosis(with 9 years and 10 years of experience in CT reading).Disagreements were solved by consensus. The final diagnosis was using histopathology results as the gold standard. Interobserver variability was calculated using Cohen's kappa and Quadratic Weighted Kappa. The differences between benign and malignant masses were compared using the chi-square test. Accuracy rate, sensitivity, specificity, and the area under the curve (AUC) were calculated as the primary indices for diagnostic accuracy. McNemar test was used to evaluate the difference in diagnostic accuracy between dual-energy CT angiography images and original CT images. A two-tailed P < 0.05 was considered statistically significant. RESULTS: A total of 64 patients with 28 malignant masses and 47 benign masses were included. The characteristics of malignant masses showed the branch number of the main feeding artery was ≥ 3(71.4%, 20/28), the course of feeding artery(100%, 28/28) and the mass shape(85.7%, 24/28) were both irregulars. Those characteristics all had statistical differences between benign and malignant masses(all P = 0.000). The Models using the course of feeding artery as a predictor, the accuracy, sensitivity and positive likelihood ratio were 89.3% (95 % CI: 0.801, 0.947), 100% (95 % CI: 0.850, 1) and 5.875(95 % CI: 3.125, 11.044), respectively. The diagnostic accuracy of every model by dual-energy CT angiography was significantly higher than that by original CT imaging(all P = 0.000). CONCLUSIONS: The dual-energy CT angiography can distinguish malignant pelvic masses from benign masses by providing characteristic images of feeding arteries and mass shape.


Assuntos
Angiografia , Angiografia por Tomografia Computadorizada , Angiografia/métodos , Feminino , Humanos , Variações Dependentes do Observador , Estudos Prospectivos , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X/métodos
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