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1.
Semin Cancer Biol ; 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32014608

RESUMO

Strictly regulated protein degradation by ubiquitin-proteasome system (UPS) is essential for various cellular processes whose dysregulation is linked to serious diseases including cancer. Skp2, a well characterized component of Skp2-SCF E3 ligase complex, is able to conjugate both K48-linked ubiquitin chains and K63-linked ubiquitin chains on its diverse substrates, inducing proteasome mediated proteolysis or modulating the function of tagged substrates respectively. Overexpression of Skp2 is observed in various human cancers associated with poor survival and adverse therapeutic outcomes, which in turn suggests that Skp2 engages in tumorigenic activity. To that end, the oncogenic properties of Skp2 are demonstrated by various genetic mouse models, highlighting the potential of Skp2 as a target for tackling cancer. In this article, we will describe the downstream substrates of Skp2 as well as upstream regulators for Skp2-SCF complex activity. We will further summarize the comprehensive oncogenic functions of Skp2 while describing diverse strategies and therapeutic platforms currently available for developing Skp2 inhibitors.

2.
Eur J Protistol ; 73: 125675, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-32036251

RESUMO

Ciliated protists represent a morphologically and genetically distinct group of single-celled eukaryotes which can reproduce asexually and sexually. Morphogenesis occurs in both asexual and sexual modes of reproduction which is of interest for researchers investigating cell differentiation, regeneration, systematics and evolution. However, studies of morphogenesis have concentrated almost entirely on the asexual mode. Here we use protargol staining to investigate the morphogenetic processes during sexual reproduction in the model species Euplotes vannus (Müller). The major events include: (1) two rounds of morphogenesis occur during sexual reproduction, i.e., conjugational and postconjugational reorganization; (2) in both processes the oral primordium is generated de novo in a pouch beneath the cortex; (3) the frontoventral-transverse cirri anlagen are formed de novo and fragment in a 3:3:3:3:2 pattern; (4) the leftmost cirrus and the paroral membrane do not change during conjugational morphogenesis, but reorganize de novo during postconjugational morphogenesis; (5) marginal cirral anlagen are formed de novo in both morphogenetic processes; (6) two or three caudal cirri are formed at the ends of the rightmost two or three old dorsal kineties; (7) the dorsal kineties are retained entirely. These results can serve as reference to investigate the morphogenetic events in the different stages of sexual reproduction.

3.
Sci Total Environ ; 715: 136575, 2020 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-32007870

RESUMO

The presence of persistent free radicals (PFR) in biochars may greatly broaden the application of biochars in pollution control, but may also cause negative impacts to the environment. Understanding the structural basis and the formation mechanisms of PFR is essential for a targeted biochar production and application. This study used rice straw (RS), a ubiquitous agricultural waste, to investigate the generation processes of PFR in relation to RS pyrolysis kinetics. Based on a detailed thermogravimetric (TG) and derivative thermogravimetric (DTG) analysis, the activation energy was calculated by Kissinger-Akahira-Sunose (KAS) and Flynn-Wall-Ozawa (FWO) methods. This work combined pyrolysis kinetics analysis and solid particle characterization. Our results showed that lignin started to pyrolyze at a lower temperature than cellulose and hemicellulose. Lignin was the main factor for PFR generation. Chemical bond breaking contributed only slightly to PFR formation. The reconfiguration of the carbonaceous structures may be a more important contributor to PFR formation, while the cross-linking between different compositions and the interactions between the chemical compositions and inorganic minerals may play a significant role for PFR generation and stabilization in RS. This study provides useful theoretical basis to understand the thermal pyrolysis process of RS and the manipulation of biochar properties.

4.
J Craniofac Surg ; 2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-31977690

RESUMO

Recently, an increasing trend of the birth prevalence of anotia/microtia is observed in China, contributed by changes of social environment and lifestyle. There seems to be no major breakthroughs in exact pathogenesis of microtia, though the research results related to molecular genetics unceasingly appear. In this review, the authors focus on the results of various research methods which the authors regard as the preferential suspicious gene pool to facilitate the exploration of the pathogenic genes of microtia, knowing that the mechanism of microtia is very complicated. The advantages and limitations of these various approaches will also be systematically delineated. The authors believe that this review will give a deep insight in the genetic research of microtia and help plastic surgeons manage congenital microtia more effectively.

5.
J Craniofac Surg ; 2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-31977716

RESUMO

Autologous costal cartilage graft is an important material in orthopedic surgery. However, postoperative deformity of costal cartilage in donors is also a matter of concern. In our clinical experience, the preservation of the intercostal perichondrium, the replantation of part of the costal cartilage, and wearing an elastic chest strap for half a year are all ways to avoid thoracic deformity. Methods by which to avoid thoracic deformity is still the focus of our efforts.

7.
Sci Total Environ ; 713: 136559, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31951837

RESUMO

The colloidal heteroassociation between natural mineral colloids and engineered nanoparticles (ENPs) can reduce the bioavailability and toxicity of the ENPs. However, the efficacy of this heteroassociation-based entrapment of ENPs depends on the intrinsic material properties of the particles and the physicochemical parameters of the aquatic environment. Natural organic matter (NOM)-induced surface modifications of clay colloids, functionalization of ENPs, and efficiency of counterions as effective coagulants profoundly affect the effectiveness of heteroaggregation-based attenuation of anthropogenic colloids. In this study, tannic acid (TA), a surrogate of NOM, prevented the edge-to-face self-association of sodium-saturated kaolinite (Na-kaolinite) at acidic pH, as evaluated from the transverse proton spin-spin relaxation data (T2). Likewise, fullerene water suspension (FWS) adhesion to Na-kaolinite prevented the self-association of Na-kaolinite and enhanced the colloidal stability. At pH 4 and diffusion-limited aggregation regime salt concentrations, the Na-kaolinite and FWS heteroaggregation rates were lower than the Na-kaolinite homoaggregation rates, and eventually reached a plateau. The higher colloidal stability of the Na-kaolinite and FWS binary mixture than that of Na-kaolinite, regardless of stronger charge screening by Ca2+, reflects steric stabilization. However, at pH 7, the increased electrostatic barrier reduces the feasibility of colloidal heteroassociation between Na-kaolinite and FWS; thus, higher salt concentrations are required to initiate aggregation. Weak adsorption of TA on Na-kaolinite at pH 7 facilitated stronger π-π interactions with FWS. All suspensions exhibited faster aggregate growth at pH 7 than pH 4, possibly due to the stronger cation response at pH 7. In situ atomic force microscopy imaging and line profile plots of Na-kaolinite, TA, and FWS mixture in CaCl2 further corroborated the difference in the heteroaggregation rates observed at the two different pH values. Thus, TA-induced surface functionalization of FWS and the consequent increased electrostatic barrier to heteroassociation with Na-kaolinite may facilitate the environmental mobility of FWS in aquatic media.

8.
Sci Total Environ ; 713: 136663, 2020 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-31958735

RESUMO

The ash content of municipal sewage sludge is generally high. However, the manner in which the composition of ash affects biochar properties and sorption remains unclear. Sewage sludge from two cities, Chongqing and Kunming, were pyrolyzed at different temperatures to produce biochar in this work. The physicochemical properties of biochar were investigated by bulk chemical characteristics (such as FTIR, XPS, Raman analysis, and elemental analysis) and benzene polycarboxylic acid (BPCA) molecular biomarkers, after which they were correlated with sorption characteristics. In comparison with biochar from Chongqing sewage sludge (CSS), biochar from Kunming sewage sludge (KSS) showed stronger polarity, a larger specific surface area (SSA) and more functional groups, but a lower degree of graphitization and aromatization. These differences may result from the higher aluminum (Al) content of KSS. The single-point sorption coefficient Kd values of biochar derived from CSS and KSS were analyzed together. Kd was positively correlated with the SSA and pore volume of sewage sludge and biochar produced at 200-300 °C. For biochar produced at 300-700 °C, the Kd value was positively correlated with the O content, O/C and (O + N)/C. The pyrolysis temperature of 300 °C was a threshold temperature for Cu(II) sorption onto biochar, at which there was a balance between decreased oxygen-containing functional groups and increased SSA. The findings of this study show that higher Al content in sewage sludge was beneficial to pore volume enlargement and functional group retention during the pyrolysis process.

9.
Environ Pollut ; 260: 113977, 2020 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-31991352

RESUMO

Condensed organic matters (COM) with black carbon-like structures are considered as long-term carbon sinks because of their high stability. It is difficult to distinguish COM from general organic matter by conventional chemical analysis, thus the contribution by and interaction mechanisms of organo-mineral complexes in COM stabilization are unclear and generally neglected. Molecular markers related to black carbon-like structures, such as benzene polycarboxylic acids (BPCAs), are promising tools for the qualitative and quantitative analysis of COM. In this study, one natural soil and two cultivated soils with 25 y- or 55 y-tillage activities were collected and the distribution characteristics of BPCAs were detected. All the investigated soils showed similar BPCA distribution pattern, and over 60% of BPCAs were detected in clay fraction. The extractable BPCA contents were substantially increased after mineral removal. The ratios of BPCA contents before and after mineral removal indicate the extent of COM-mineral particle interactions, and our results suggested that up to 73% COM were protected by mineral particles, and more stronger interactions were noted on clay than on silt. The initial cultivation dramatically decreased COM-clay interactions, and this interaction was recovered only slowly after 55-y cultivation. Kaolinite and muscovite are important for COM protection. But a possible negative correlation between BPCAs and reactive iron oxides of the cultivated soils suggested that iron may promote COM degradation when disturbed by tillage activities. This study provided a new angle to study the stabilization of COM and emphasized the importance of organo-mineral complexes for COM stabilization.

10.
Int J Med Robot ; : e2079, 2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-31953893

RESUMO

PURPOSE: The surgeon is not timely in direct control his field of view. Autonomous laparoscope control can provide appropriate surgical field of view, and facilitate the intelligent level of surgical robot system. METHODS: This study explores an autonomous laparoscope control framework for semi-autonomous surgery. We propose a novel concept integrates two forms of Remote Center of Motion (RCM) constraint. We also propose a novel safety-RCM model to cope with the collision condition. We modify the image Jacobian matrix to realize RCM constraint. The two models constitute a dual-RCM constraint for robot laparoscope arm. We perform validation of the algorithm with two experiments. RESULTS: The experimental results show that the RCM position error can be reduced with the dual-RCM constraint. Owing to safety-RCM model, autonomous surgical field of view control could still be realized in case of collision. CONCLUSION: The autonomous laparoscope control could be realized with safety-RCM and dual-RCM algorithms. This article is protected by copyright. All rights reserved.

11.
J Dermatolog Treat ; : 1-8, 2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-31916474

RESUMO

Keloid is a common and frequently-occurring disease in plastic surgery, and its ugly appearance and itching symptoms bring mental and life pain to patients. However, the clinical treatment of keloid, such as drug injection treatment, surgical resection, cryotherapy, laser treatment and other therapeutic effects are poor. Since the discovery of tumor necrosis factor related apoptosis inducing ligand (TRAIL) in 1995, its selective apoptosis on tumor cells makes it have a great prospect in the targeted treatment of tumor. In recent years, it has been found that the formation of keloid is related to the imbalance of apoptosis of fibroblasts in scar and the binding of TRAI to its receptor mediates the apoptosis of fibroblasts. Therefore, the use of TRAIL and TRAIL-R2/death receptor 5 (DR5) in the treatment of keloid has become a hot research topic. In this paper, the present situation, mechanism and development prospect of TRAIL and TRAIL-R2/DR5 targeted treatment of keloid were reviewed, which provided a reference for promoting the development of keloid treatment.

12.
Cells ; 9(1)2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31936362

RESUMO

Granulosa cells (GCs) are the key components of ovarian follicles for regulating oocyte maturation. Previous established GC lines have allowed prolonged proliferation, but lost some physiological features owing to long-term immortalization. This study was to establish an induced immortal porcine GC line with reversible proliferation status by the tetracycline inducible (Tet-on) 3G system. Our conditional immortal porcine GCs (CIPGCs) line steadily propagated for at least six months and displayed primary GC morphology when cultured in the presence of 50 ng/mL doxycycline [Dox (+)]. Upon Dox withdrawal [Dox (-)], Large T-antigen expression, reflected by mCherry fluorescence, gradually became undetectable within 48 h, accompanied by less proliferation and size increase. The levels of estradiol and progesterone, and the expression of genes associated with steroid production, such as CYP11A1 (cytochrome P450 family 11), 3ß-HSD (3ß-hydroxysteroid dehydrogenase), StAR (steroidogenic acute regulatory protein), and CYP19A1 (cytochrome P450 family 19 subfamily a member 1), were all significantly higher in the Dox (-) group than Dox (+) group. The CIPGCs could switch into a proliferative state upon Dox induction. Interestingly, the expression of StAR and CYP19A1 in the CIPGCs (-Dox) was significantly increased by adding porcine follicular fluid (PFF) to mimic an ovary follicle environment. Moreover, PFF priming the CIPGCs in Dox (-) group resulted in similar estradiol production as that of primary GC, and enabled this cell line to respond to gonadotrophins in estradiol production. Collectively, we have established an inducible immortal porcine GC line, which offers a unique and valuable model for future research on the regulation of ovarian functions.

13.
Int J Med Robot ; 16(1): e2049, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31677231

RESUMO

BACKGROUND: Intelligent surgical robot has great significance to alleviate the fatigue of surgeons. In the minimally invasive surgery robot system, adding intelligent control method to the laparoscope control has great realizability and significance. METHODS: Depth independent image Jacobian matrix was modified to make it suitable for laparoscope trocar constraint. We propose a method for intelligent and autonomous adjustment of surgeon's surgical field of view, enabling it to track and predict the motion trajectory of surgical instruments. RESULTS: The result of experiment shows that the proposed method could realize tracking the surgical instruments and adjusting the surgical field of view autonomously. In case of occlusion, motion trajectory of surgical instruments can be predicted. CONCLUSION: The intelligent laparoscope system could improve the intelligent level of surgical robot system. Given providing "a third hand" for the surgeon, the proposed system is a highly improvement for semi-autonomous surgical robot system.

14.
J Eukaryot Microbiol ; 67(1): 76-85, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31419341

RESUMO

We report the morphology and morphogenesis of Urosoma caudata (Ehrenberg, 1833) Berger, 1999 based on in vivo observation and protargol impregnation and provide an improved diagnosis of U. caudata based on previous and current work. Urosoma caudata differs from its congeners mainly by the combination of the following features: tail-like posterior end, colorless cortical granules, and two macronuclear nodules. Urosoma caudata shares most of the ontogenetic features with its congeners: the oral primordium of the opisthe develops apokinetally, and the frontal-ventral-transverse cirral anlagen develop in five streaks. However, a unique morphogenetic characteristic is recognizable: the anlagen of three dorsal kineties occur de novo to the left of the parental structures differing from their intrakinetal origin in other Urosoma species. The first record of the 18S rRNA gene sequence for the species is also provided. Phylogenetic analyses based on 18S rRNA gene sequence data suggest that the genus Urosoma is a nonmonophyletic group.

15.
Int J Pediatr Otorhinolaryngol ; 129: 109771, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31731016

RESUMO

OBJECTIVE: To explore correlations between post-treatment outcomes of non-surgical correction for cryptotia and treatment time and other influence factors. METHODS: Forty-seven consecutive patients with 64 cryptotias were treated with the adjusted external stretching device and followed up over 12 months. A subjective evaluation scale was designed for patients to collect clinical data. Pretreatment and posttreatment evaluation were conducted by two blinded investigators. The correlations between influence factors and outcomes were explored through fractional polynomial method, multiple logistic regression, and robust linear regression methods. RESULTS: Thirty-five patients with 49 cryptotias were included. Twenty-nine cryptotias (23 patients) have been successfully managed. Two of 17 unilateral cryptotias achieved nearly complete symmetry. The final optimal cutoff value for initiating treatment time is 6 months and for the duration of treatment per day is 5 h per day. Positive relationships between initiating treatment time >6 months and onset time, type II and onset time, initiating treatment time >6 months and effect stabilization time were observed. CONCLUSIONS: Initiating treatment time <6 months and duration of treatment per day >5 h benefit for the posttreatment outcomes. Patients wearing the device under 6 months old would have earlier onset time and effect stabilization time. It is hard to achieve complete bilateral symmetry in unilateral patients. The adjustable devices can used for the auricles with different sizes and removed and equipped conveniently.

16.
Bioorg Med Chem Lett ; 30(2): 126472, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31859156

RESUMO

A new series of Vinpocetine derivatives were synthesized and evaluated for their inhibitory activity on PDE1A in vitro. Seven compounds with higher inhibitory activity were selected for surface plasmon resonance (SPR) binding experiments. Compared with Vinpocetine, these high potency compounds presented a higher binding affinity with PDE1A, which was consistent with inhibitory activity. After further screening, compounds 5, 7, 21, 34 and Vinpocetine were selected to examine the vasorelaxant effects on endothelium-intact rat thoracic aortic rings. The study suggested that the effects of compounds 7 and 21 were the most significant with the maximum value of 93.46 ±â€¯0.77% and 92.90 ±â€¯0.78% (n = 5) at a concentration of 100 µM respectively. Based on these studies, compounds 7 and 21 were considered for further development as hit compounds.

17.
Bioorg Med Chem Lett ; 30(2): 126585, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31859158

RESUMO

Firstly, a series of Isosteviol derivatives were synthesized and evaluated for FXa inhibitory activity. Among these compounds, the inhibitory activity of compounds 22, 35 and 38 on FXa was better than that of Isosteviol. Secondly, surface plasmon resonance (SPR) assays were performed for selected compounds. Compounds 22, 35, 38 have similar kinetic signatures, and affinity values were at µM level. Thirdly, compounds 22 and 35 displayed moderate-to-high anticoagulation activity and showed similar sensitivity to PT and aPTT. These findings will provide new insight into the exploration of FXa inhibition.

18.
Int J Pediatr Otorhinolaryngol ; 130: 109801, 2019 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-31821964

RESUMO

OBJECTIVE: Numerous corrective methods have been successfully applied in concha-type microtia reconstruction over the past several decades, and autogenous rib cartilage grafting has become a routine technique in a two or three-stage operation. However, it still remains a challenge due to the effective use of the large volume of the remnant cartilage and skin involved. The objective of this study was to clarify how this remnant cartilage and skin could be manipulated for new suitable treatment strategies without autogenous costal cartilage grafting. METHODS: A total of 424 patients with concha-type microtia operated at our Center from January of 2012 to June of 2019 have been reviewed and analyzed cases. At the same time, a classification system for grading the severity of concha-type microtia was created on the basis of anatomical findings and ear size. RESULTS: A total of 436 ear cases (involving 424 patients), showing concha-type microtia, were included in our study and reviewed through medical records, photographs, analysis of surgical methods, and postoperative outcomes. The concha-type microtia were classified into four graded types: Grade I (n = 151), Grade II (n = 101), Grade III (n = 93), and Grade IV (n = 79). A total of 352 ears in 345 patients with Grade I to III concha-type microtia were followed up for 1 month to 7 years (average, 14.7 months). 329 patients (95.4%) were satisfied with the aesthetic outcomes of the corrected ear. CONCLUSIONS: Individual corrective methods and aesthetic outcomes for patients with Grade I to III of deformity were described in this study. The authors present new suitable approaches according to a progressive classification system which provide conservative and individualized methods of treatment in early stages of life.

19.
Exp Ther Med ; 18(6): 4575-4582, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31807147

RESUMO

Objective measurement is important for diagnosing congenital or acquired auricular abnormalities and the evaluation of therapeutic efficacy. However, methods applied in the past were mostly inaccurate and unreliable. The present study aimed to introduce five standardized indices for auricle measurement and present a highly precise and reliable methodology combining three-dimensional (3D) scanning techniques and the Materialise Mimics software for the evaluation of auricle sizes. A total of 20 normal ears were measured independently by four surgeons using the standardized digital method with 3D scanning technique and the traditional manual method. Parameters of the auricle, including the length and width, arc length, cranioauricular height and angle were measured using the Mimics software. Paired t-test, Wilcoxon signed rank test and intra-class correlation coefficients (ICC) were performed on the data to assess the precision, uniformity and observer independence of the method. Pearson's product moment correlation was calculated to assess the correlation between auricle length and width in addition to the correlation between cranioauricular height and angle. No significant differences were indicated between measurements of five auricular parameters made by two surgeons using the digital method. However, significant differences were found using the manual method (P<0.01). ICC values derived from digital measurements ranged from 0.901 to 0.987, whereas those derived from manual measurements ranged from 0.526 to 0.807. These results suggested that the standardized digital method was replicable and reliable compared with the traditional manual method. Pearson's coefficient analysis showed that there was a significant correlation between cranioauricular height and angle (P<0.05), but no correlations were found between the height and width of the auricle (P>0.05). Taken together, data from the present study suggested that measurements of the length and width, arch length, and cranioauricular height and angle of auricles using the standardized digital method combining 3D scanning with the Mimics software were comprehensive, precise, convenient, repeatable and reliable.

20.
Antioxidants (Basel) ; 8(12)2019 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-31835711

RESUMO

Female reproductive (ovarian) aging is distinctively characterized by a markedly reduced reproductive function due to a remarkable decline in quality and quantity of follicles and oocytes. Selenium (Se) has been implicated in playing many important biological roles in male fertility and reproduction; however, its potential roles in female reproduction, particularly in aging subjects, remain poorly elucidated. Therefore, in the current study we used a murine model of female reproductive aging and elucidated how different Se-levels might affect the reproductive efficiency in aging females. Our results showed that at the end of an 8-week dietary trial, whole-blood Se concentration and blood total antioxidant capacity (TAOC) were significantly reduced in Se-deficient (0.08 mg Se/kg; Se-D) mice, whereas both of these biomarkers were significantly higher in inorganic (0.33 mg/kg; ISe-S) and organic (0.33 mg/kg; OSe-S) Se-supplemented groups. Similarly, compared to the Se-D group, Se supplementation significantly ameliorated the maintenance of follicles and reduced the rate of apoptosis in ovaries. Meanwhile, the rate of in vitro-produced embryos resulting from germinal vesicle (GV) oocytes was also significantly improved in Se-supplemented (ISe-S and OSe-S) groups compared to the Se-D mice, in which none of the embryos developed to the hatched blastocyst stage. RT-qPCR results revealed that mRNA expression of Gpx1, Gpx3, Gpx4, Selenof, p21, and Bcl-2 genes in ovaries of aging mice was differentially modulated by dietary Se levels. A considerably higher mRNA expression of Gpx1, Gpx3, Gpx4, and Selenof was observed in Se-supplemented groups compared to the Se-D group. Similarly, mRNA expression of Bcl-2 and p21 was significantly lower in Se-supplemented groups. Immunohistochemical assay also revealed a significantly higher expression of GPX4 in Se-supplemented mice. Our results reasonably indicate that Se deficiency (or marginal levels) can negatively impact the fertility and reproduction in females, particularly those of an advancing age, and that the Se supplementation (inorganic and organic) can substantiate ovarian function and overall reproductive efficiency in aging females.

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