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1.
J Fluoresc ; 2020 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-31897914

RESUMO

N-doped carbon dots (N-Cdots) were prepared via a solvothermal process in different solvents including water, acetone, and N,N-dimethylformamide (DMF). The red-shifted photoluminescence (PL) peaks and prolonged lifetimes were observed in the three excitation-independent samples. Considering that the similar size distribution, these variations of PL properties were mainly attributed to surface states of Cdots. The crucial effect of acetone and DMF as aprotic solvents were proposed because they can not provided hydrogen during the whole reaction process like H2O, and thus the dehydration reaction was accelerated. Much more N elements were introduced into N-Cdots. Except for N-doping, similar reaction were conducted when N and S were introduced into Cdots at the same time. Similar PL behaviour of N,S-co-doped carbon dots (N,S-Cdots) further confirmed above assumption. This work provided a simple method to control the PL behaviour of Cdots, which will have a promising future in the application of bioimaging and other fields.

2.
Eur Radiol ; 2020 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-31900697

RESUMO

OBJECTIVES: The objective of this study was to evaluate whether baseline 18F-fluorodeoxyglucose (FDG) uptake is associated with carotid plaque progression. METHODS: A total of 156 subjects with carotid plaque were enrolled and underwent carotid magnetic resonance imaging (MRI) (at baseline and the 12-month follow-up) and positron emission tomography-computed tomography (PET-CT) (baseline). Carotid plaque progression was evaluated by two indices (the incidence of plaque progression and percentage of plaque increase) with three-dimensional (3D) imaging, while the 18F-FDG uptake was evaluated by the 18F-FDG uptake levels and 18F-FDG uptake velocity. The association between plaque progression and 18F-FDG uptake was investigated by the trend test and multivariate logistic regression analysis. RESULTS: Of the 156 subjects, 80 (51.3%) showed carotid plaque progression during the 12-month follow-up. Firstly, no association was found between 18F-FDG uptake levels and plaque progression. Secondly, significant differences in the incidence of plaque progression were observed among the groups with different uptake velocities, showing a significant decreasing trend ranging from high to intermediate to low (p = 0.002, trend test). After adjusting for covariates, an adequate prediction of the 18F-FDG uptake velocity for the incidence of plaque progression was revealed (OR = 0.682, p < 0.05). In addition, no association was found between the 18F-FDG uptake velocity and the percentage of plaque increase in the subjects with plaque progression (p = 0.757, trend test). CONCLUSIONS: Our findings suggest 18F-FDG uptake velocity is independently associated with the incidence of carotid plaque progression. Additionally, the 18F-FDG uptake velocity, as another important parameter of PET-CT, warrants further study in future clinical research. KEY POINTS: • The18F-FDG uptake levels were not associated with the carotid plaque progression. • The18F-FDG uptake velocity could predict the incidence of carotid plaque progression. • The18F-FDG uptake velocity with related factors warrants more attention in future clinical research.

3.
Mol Genet Genomics ; 2020 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-31901979

RESUMO

Cervical cancer is a common gynecological malignancy with high incidence and mortality. Somatic copy number alterations (CNAs) play an important role in identifying tumor suppressor genes and oncogenes and are a useful diagnostic indicator for many cancer types. However, the genomic landscape of CNAs in cervical cancer has not yet been comprehensively characterized. In the present study, we collected 974 cervical cancer samples from different data sources. All samples were analyzed by genomic arrays to obtain high-resolution CNAs. Focal genomic regions with CNA events and potential cancer driver genes were identified by GISTIC2.0. Meanwhile, we constructed a comprehensive cervical cancer database by PHP and self-written Perl and R scripts. In total, 54 recurrent regions of amplification and deletion were detected. Frequently altered tumor suppressor genes were found in these regions, including PIK3CA, ERBB2, EP300 and FBXW7. CNA hotspots and related enriched functional categories were also identified. The incidence of chromothripsis in cervical cancer was estimated to be 6.06%, and the chromosome pulverization hotspot regions were detected. Based on the curated data, we developed CNAdbCC (http://cailab.labshare.cn/CNAdbCC/), a comprehensive database for copy number alterations in cervical cancer. We provide a user-friendly Web interface for data mining and visualization. It is the most comprehensive public database devoted exclusively to genomic alterations in cervical cancer. These results extend our molecular understanding of cervical cancer. The database will enable researchers to explore specific CNA patterns in this lethal cancer and facilitate the discovery of therapeutic candidates.

4.
Environ Technol ; : 1-16, 2020 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-31902307

RESUMO

An MBBR and CW combo bio-reactor (MBCW) was designed as a novel hybrid process for simultaneous organic, nitrogen and phosphate removal through the long-term operation. The effect of the internal recycling rate (IRR), hydraulic retention time (HRT) and chemical oxygen demand/total nitrogen (C/N) ratio were all discussed, and the recommended values were 5:1, 12 h and >6, respectively. A higher C/N ratio was a key factor for achieving a higher TN removal. The mixed biocarrier system was realized by inoculating porous polymer carriers (PPC) and cylindrical polyethylene carriers (CPC) and achieving a higher organic biodegradation and nitrification rate compared to a single carrier system. Microorganism activities and plants' uptake or utilization both contributed to the nutrient removal in a constructed wetland. High-throughput sequencing results revealed an abundant microbial diversity and a distinct microbial distribution in the whole system where Flavobacterium (14.2%), Acinetobacter (12.87%) and Rhodobacter (10.83%) dominated on PPC, Terrimonas (8.88%), Reyranella (6.61%) and Rubinisphaera (5.63%) dominated on CPC, Comamonas (4.18%), Gemmobacter (4.02%) and Hydrogenophaga (3.97%) dominated on CWs, as well as Citrobacter (53.13%) on suspended floc.

5.
Eur J Cancer Prev ; 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31922974

RESUMO

Major histocompatibility complex (MHC) class II regulatory genes play a paramount role in immune response that can exert a predominant influence on clinical outcome of Epstein-Barr virus infection consistently assumed as the main pathogenetic factor for nasopharyngeal carcinoma. To elucidate the relationship between allelic variants of MHC class II regulatory genes and susceptibility to nasopharyngeal carcinoma, a total of 28 polymorphic loci at MHC class II regulatory genes, involving CIITA, CREB1, RFX family genes (RFX5, RFXAP, and RFXANK), and NFY family genes (NFYA, NFYB, and NFYC), were genotyped by multiplex SNaPshot minisequencing in 137 patients with nasopharyngeal carcinoma and 107 healthy controls from the southern Chinese population. Allelic analysis disclosed that rs7404873, rs6498121, rs6498126, and rs56074043 shared correlations with nasopharyngeal carcinoma (Ptrend < 0.05). Further, rs6498126 on CIITA was independently associated with the risk of developing nasopharyngeal carcinoma (CC vs. GG, odds ratio: 7.386, 95% confidence interval: 1.934-28.207, Ptrend < 0.01). Conversely, rs7404873 on CIITA and rs56074043 on NFYB manifested epistatic interaction to decreased susceptibility of nasopharyngeal carcinoma (rs7404873, TT vs. GG, odds ratio: 0.256, 95% confidence interval: 0.088-0.740, Ptrend < 0.05; rs56074043, AA vs. AG, odds ratio: 0.341, 95% confidence interval: 0.129-0.900, Ptrend < 0.05). Additionally, bioinformatics analysis revealed that the three variants were transcriptional regulatory in function and might impact the expression of nearby genes. The findings suggested genetic variants on MHC class II regulatory genes contributed to nasopharyngeal carcinoma susceptibility and might provide new insights for screening high-risk population.

6.
Med Sci Monit ; 26: e920211, 2020 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-31927559

RESUMO

BACKGROUND The aim of this study was to investigate the mechanisms underlying the potential effects of hydrogen-rich water (HW) on articular cartilage in a rat osteoarthritis (OA) model. MATERIAL AND METHODS A rat model of OA was established using the modified Hulth method, and rats were forced to exercise for 30 min every day 1 week after surgery for 7 weeks. Mankin's method was used to score the severity of OA. The animals were assigned into the OA group, OA+HW group, and sham operation group. After 8 weeks, the animals in the OA group had a Mankin score >8 points, and HW was administered into the knee joint. After 2 weeks of treatment, articular cartilage was obtained for pathological examination, consisting of hematoxylin and eosin, toluidine blue, and Hoechst staining, as well as quantitative real-time PCR and Western blot analyses. This combination of pharmacological and molecular biological analyses was performed to examine the mechanism underlying the protective effect of HW on articular cartilage. RESULTS The antioxidant effects of HW suppressed oxidative damage, which may have aided the inhibition of ECM-degrading enzymes (MMP3, MMP13, ADAMT4, and ADAMT5), the upregulation of Col II and aggrecan expression, and the downregulation of COX-2, iNOS, and NO expression. The results of HE staining indicated intra-articular treatment of HW attenuated cartilage degradation. However, Hoechst staining in the OA group indicated the nuclei of the fragmented chondrocytes were condensed compared to the sham operation group, and this effect was inhibited by HW. CONCLUSIONS HW showed a protective effect against the progression of OA in an animal model, which may have been mediated by its anti-oxidant and anti-apoptotic activities.

7.
Inflammation ; 2020 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-31938979

RESUMO

The skewed T helper (Th) 2 response plays a critical role in the pathogenesis of allergic asthma. Regulatory T (Treg) cells and the regulatory cytokines are required in maintaining the homeostasis in the body. This study aims to determine the effects of a poly(lactic-co-glycolic) acid (PLGA)-ovalbumin (OVA)+A20 (a ubiquitin E3 ligase) nanovaccine on inhibiting allergic asthma in a murine model. In this study, A20 and OVA (a model antigen) were encapsulated into PLGA to be a nanovaccine (PLGA-OVA+A20). An allergic asthma murine model was developed with OVA as the specific antigen to test the role of PLGA-OVA+A20 nanovaccine in maintaining the immune homeostasis in the airway tissues. The results showed that PLGA-OVA+A20 nanovaccine inhibited the asthma responses in mice by suppressing Th2 inflammatory responses, promoting the generation of Treg cells in the airway tissues. We conclude that the PLGA-OVA+A20 nanovaccine has a marked inhibitory effect on the airway allergic response in sensitized mice by significantly promoting the generation of Treg cell and IL-10. The data suggest that PLGA-OVA+A20 has translational potential in the treatment of allergic asthma.

8.
Int J Biol Sci ; 16(2): 216-227, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31929750

RESUMO

Background and aims: Dysfunction of the immune regulatory system plays a role in the pathogenesis of allergic rhinitis (AR). The underlying mechanism needs to be further investigated. Published data indicate that soluble CD83 (sCD83) has immune regulatory activities. This study aims to investigate the role of sCD83 in the alleviation of experimental AR. Methods: Peripheral blood samples were obtained from AR patients. Serum levels of sCD83 were determined by enzyme-linked immunosorbent assay. A murine AR model was developed to test the effects of sCD83 on suppressing experimental AR. Results: We found that serum levels of sCD83 in the AR group were lower than that in the healthy control group. A negative correlation was identified between the serum sCD83 levels and the frequency of T helper-2 (Th2) cells. The low serum sCD83 levels were also associated with the Bcl2L12 expression in antigen-specific Th2 cells. Exposure to sCD83 enhanced the responsiveness of antigen-specific Th2 cells to apoptosis inducers via suppressing the Bcl2L12 expression. Administration of sCD83 efficiently suppressed experimental AR. Conclusions: sCD83 contributes to immune homeostasis by regulating CD4+ T cell activities. Administration of sCD83 may have translational potential for the treatment of AR or other allergic diseases.

9.
Endocrine ; 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31940133

RESUMO

PURPOSE: Previous studies revealed that high serum uric acid (SUA) levels correlated with increased triglyceride to high-density lipoprotein cholesterol (TG/HDL-C) ratio. However, evidence is lacking regarding whether TG/HDL-C is an independent risk factor or just a simple marker of hyperuricemia. We aimed to investigate the relationship between TG/HDL-C and the risk of hyperuricemia in Chinese population. METHODS: This retrospective cohort study involved 15,198 subjects (43.14 ± 13.13 years, 54.9% men) who were free of hyperuricemia at baseline. The association between TG/HDL-C and the risk of hyperuricemia, in the total sample and stratified by subgroups, was examined by multiple logistic regression analyses. RESULTS: During 4 years follow-up, hyperuricemia occurred in 2365 (15.6%) participants. The cumulative incidence of hyperuricemia was significantly elevated with increasing TG/HDL-C quartiles (5.9, 10.8, 18.4, and 27.5%, respectively). After multivariate adjustment, the odds ratio for hyperuricemia in the highest compared with the lowest quartile of TG/HDL-C was 1.80 (95% confidence interval [CI] 1.49, 2.18), and each SD increment of TG/HDL-C ratio caused a 10% additional risk for hyperuricemia. Moreover, subgroup analyses showed that the association between TG/HDL-C and the risk of hyperuricemia was more pronounced in women and normal-weight adults. The results were consistent when analyses were restricted to participants without metabolic syndrome. CONCLUSIONS: TG/HDL-C ratio was positively related to the risk of hyperuricemia in Chinese population, particularly in women and normal-weight individuals. These findings suggested the potential of TG/HDL-C ratio to serve as an independent risk indicator in the prevention of hyperuricemia.

10.
J Oleo Sci ; 2020 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-31941867

RESUMO

Activity changes after olive oil (OO), pomegranate seed oil (PSO), and grape seed oil (GSO) were formulated into self-nanoemulsifying systems (SNES), were examined in this study. Only GSO SNES dramatically enhanced antioxidant activity of GSO. SNES from OO and PSO did not exert obvious impact on radical quenching ability of the oils. Though PSO exhibited significantly stronger strength over OO in suppressing E. coli (p < 0.05), the inhibitory effect of OO SNES against E. coli became slightly higher than that of PSO SNES. Similar phenomenon happened in GSO, OO, and their SNES for preventing Yeast growth. The study indicated that SNES sometimes reversed the strength order of the original oils in inhibiting bacteria.

11.
Cell Prolif ; : e12742, 2020 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-31943454

RESUMO

OBJECTIVES: Hypoxia is an important risk factor for pulmonary arterial remodelling in pulmonary arterial hypertension (PAH), and the Janus kinase 2 (JAK2) is believed to be involved in this process. In the present report, we aimed to investigate the role of JAK2 in vascular smooth muscle cells during the course of PAH. METHODS: Smooth muscle cell (SMC)-specific Jak2 deficient mice and their littermate controls were subjected to normobaric normoxic or hypoxic (10% O2 ) challenges for 28 days to monitor the development of PAH, respectively. To further elucidate the potential mechanisms whereby JAK2 influences pulmonary vascular remodelling, a selective JAK2 inhibitor was applied to pre-treat human pulmonary arterial smooth muscle cells (HPASMCs) for 1 hour followed by 24-hour hypoxic exposure. RESULTS: Mice with hypoxia-induced PAH were characterized by the altered JAK2/STAT3 activity in pulmonary artery smooth muscle cells. Therefore, induction of Jak2 deficiency in SMCs protected mice from hypoxia-induced increase of right ventricular systolic pressure (RVSP), right ventricular hypertrophy and pulmonary vascular remodelling. Particularly, loss of Jak2 significantly attenuated chronic hypoxia-induced PASMC proliferation in the lungs. Similarly, blockade of JAK2 by its inhibitor, TG-101348, suppressed hypoxia-induced human PASMC proliferation. Upon hypoxia-induced activation, JAK2 phosphorylated signal transducer and activator of transcription 3 (STAT3), which then bound to the CCNA2 promoter to transcribe cyclin A2 expression, thereby promoting PASMC proliferation. CONCLUSIONS: Our studies support that JAK2 could be a culprit contributing to the pulmonary vascular remodelling, and therefore, it could be a viable target for prevention and treatment of PAH in clinical settings.

12.
Nano Lett ; 2020 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-31944125

RESUMO

Oxides heterostructure has attracted a lot of interests because of its rich exotic phenomena and potential applications. Recently, a greatly enhanced tunneling electroresistance (TER) of ferroelectric tunnel junctions (FTJs) has been realized in such heterostructures. However, our understanding on the electronic structure of resistance response with polarization reversal and the origin of huge TER are still lacking. Here, we report on electronic structures, particularly at the interface and surface, and the control of the spontaneous polarization of BaTiO3 films by changing the termination of a SrTiO3 substrate. Interestingly, unusual electron and hole midgap states are concurrently formed and accompanied by orbital reconstructions, which determine the ferroelectric polarization orientation in the BaTiO3/SrTiO3. Such unusual midgap states, which yield a strong electronic screening effect, reduce the ferroelectric barrier width and height, and pin the ferroelectric polarization, lead to a dramatic enhancement of the TER effect. The midgap states are also observed in BaTiO3 films on electron-doped Nb:SrTiO3 revealing its universality. Our result provides new insight into the origin of the huge TER effect and opens a new route for designing ferroelectric tunnel junctions-based devices with huge TER through interface engineering.

13.
Sci Total Environ ; 713: 136605, 2020 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-31951842

RESUMO

Purple anoxygenic phototrophs have been recently attracted substantial attention for their growing potential in wastewater treatment and their diverse metabolic patterns can be regulated for process control and optimization. In this study, the photoheterotrophic metabolism of Rhodopseudomonas palustris (R. palustris) was modified by photosynthetic electron uptake using a poised electrode which was explored to enhance removal of veterinary antibiotic from aqueous medium. The results showed that R. palustris grown as biofilm on electrode surface had excellent photoelectroactive activity and the photosynthetic electron uptake from the photoelectroactive biofilm significantly enhanced antibiotic florfenicol (FLO) degradation. The specific degradation rate of FLO at the set electrode potential of 0 V was 2.59-fold higher than that without applied potential. Enhanced co-metabolic reductive dehalogenation by use of the photosynthetic electrons extracted from co-substrate was mainly responsible for FLO degradation which eliminated the antibacterial activity of FLO. The electrode potential controlled the processes of photosynthetic electron uptake and its resultant FLO degradation. The fastest degradation of FLO was achieved at 0 V because the electrode poised at this potential stroke a proper balance between the enhancing photosynthetic electron uptake by serving as electron acceptor and minimizing competition with FLO for the photosynthetic electron from co-substrate. The activity of photoelectroactive biofilm was not negatively affected by FLO at environmental relevant concentration, suggesting its great potential for removal of antibiotic contaminants in wastewater. R. palustris could serve as a reservoir for floR resistance gene but its abundance can be diminished by choosing appropriate electrode potential.

14.
J Environ Sci (China) ; 87: 250-259, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31791498

RESUMO

Water-uptakes of pure sodium carbonate (Na2CO3), pure ß-alanine and internally mixed ß-alanine/Na2CO3 aerosol particles with different mole ratios are first monitored using attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) technique. For pure Na2CO3 aerosol particles, combining the absorptions at 877 and 1422 cm-1 with abrupt water loss shows the efflorescence relative humidity (ERH) of 62.9%-51.9%. Upon humidifying, solid Na2CO3 firstly absorbs water to from Na2CO3·H2O crystal at 72.0% RH and then deliquesces at 84.5% RH (DRH). As for pure ß-alanine particles, the crystallization takes place in the range of 42.4%-33.2% RH and becomes droplets at ~88.2% RH. When ß-alanine is mixed with Na2CO3 at various mole ratios, it shows no efflorescence of Na2CO3 when ß-alanine to Na2CO3 mole ratio (OIR) is 2:1. For 1:1 and 1:2 ß-alanine/Na2CO3 aerosols, the ERHs of Na2CO3 are 51.8%-42.3% and 57.1%-42.3%, respectively. While ß-alanine crystal appears from 62.7% RH for 2:1 and 59.4% RH for both 1:1 and 1:2 particles and lasts to driest state. On hydration, the DRH is 44.7%-75.2% for Na2CO3 with the OIR of 1:1 and 44.7%-69.0% for 1:2 mixture, and those of ß-alanine are 74.8% for 2:1 mixture and 68.9% for two others. After the first dehumidification-humidification, all the water contents decrease despite of constituent fraction. And at ~92% RH, the remaining water contents are 92%, 89% and 82% at ~92% RH, corresponding to OIR of 2:1, 1:1 and 1:2 mixed system, respectively.


Assuntos
Alanina/química , Carbonatos/química , Modelos Químicos , Espectroscopia de Infravermelho com Transformada de Fourier , Molhabilidade
15.
J Sci Food Agric ; 100(1): 315-324, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31525262

RESUMO

BACKGROUND: In order to utilize tilapia skin gelatin hydrolysate protein, which is normally discarded as industrial waste in the process of fish manufacture, we study the in vivo and in vitro angiotensin-I-converting enzyme (ACE) inhibitory activity of the peptide Leu-Ser-Gly-Tyr-Gly-Pro (LSGYGP). The aim was to provide a pharmacological basis of the development of minimal side effects of ACE inhibitors by comparative analysis with captopril in molecular docking. RESULTS: This peptide from protein-rich wastes showed excellent ACE inhibitory activity (IC50  = 2.577 µmol L-1 ) and exhibited a mixed noncompetitive inhibitory pattern with Lineweaver-Burk plots. Furthermore, LSGYGP and captopril groups both showed significant decreases in blood pressure after 6 h and maintained good digestive stability over 4 h. Molecular bond interactions differentiate competitive captopril upon hydrogen bond interactions and Zn(II) interaction. The C-terminal Pro generates three interactions (hydrogen bonds, hydrophilic interactions and Van der Waals interactions) in the peptide and effectively interacts with the S1 and S2 pockets of ACE. CONCLUSION: LSGYGP, with an IC50 value of 2.577 µmol L-1 , has an antihypertensive effect in spontaneously hypertensive rats. Through comparison with captopril, this study revealed that LSGYGP may be a potential food-derived ACE inhibitory peptide and could act as a functional food ingredient to prevent hypertension. © 2019 Society of Chemical Industry.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/química , Anti-Hipertensivos/química , Captopril/química , Hipertensão/tratamento farmacológico , Peptídeos/química , Sequência de Aminoácidos , Inibidores da Enzima Conversora de Angiotensina/administração & dosagem , Inibidores da Enzima Conversora de Angiotensina/metabolismo , Animais , Anti-Hipertensivos/administração & dosagem , Anti-Hipertensivos/metabolismo , Pressão Sanguínea/efeitos dos fármacos , Captopril/administração & dosagem , Ciclídeos , Digestão , Proteínas de Peixes/química , Trato Gastrointestinal/metabolismo , Humanos , Ligações de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Hipertensão/metabolismo , Hipertensão/fisiopatologia , Cinética , Masculino , Simulação de Acoplamento Molecular , Peptídeos/metabolismo , Peptídeos/farmacologia , Peptidil Dipeptidase A/química , Peptidil Dipeptidase A/metabolismo , Hidrolisados de Proteína/química , Hidrolisados de Proteína/metabolismo , Ratos , Ratos Endogâmicos SHR
16.
Molecules ; 24(23)2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31783603

RESUMO

The secondary structure of a protein has been identified to be a crucial indicator that governs its water solubility. Tilapia protein isolate (TPI), soybean protein isolate (SPI), and tilapia-soybean protein co-precipitates (TSPC3:1, TSPC2:1, TSPC1:1, TSPC1:2, and TSPC1:3) were prepared by mixing tilapia meat and soybean meal at different mass ratios. The results demonstrated that the water solubility of TSPCs was significantly greater than that of TPI (p <0.05). The changes in ultraviolet-visible and near-ultraviolet circular dichroism spectra indicated that the local structure of TSPCs was different from that of TPI and SPI. Fourier transform infrared Spectroscopy revealed the co-existence of TPI and SPI structures in TSPCs. The secondary structures of TSPCs were predominantly α-helix and ß-sheet. TSPC1:1 was unique compared to the other TSPCs. In addition, there was a good correlation between the water solubility and secondary structure of TSPCs, in which the correlation coefficients of α-helix and ß-sheet were -0.964 (p <0.01) and 0.743, respectively. TSPCs displayed lower α-helix contents and higher ß-sheet contents compared to TPI, which resulted in a significant increase in their water solubility. Our findings could provide insight into the structure-function relationship of food proteins, thus creating more opportunities to develop innovative applications for mixed proteins.

17.
Theriogenology ; 2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31787469

RESUMO

Spermiogenesis is a highly organized process of the metamorphosis of round spermatids into spermatozoa in the testes. Autophagy is involved in the physiological process of spermiogenesis and its crucial role in germ-plasm clearance conserved across kingdoms. However, the fate of by-products generated through autophagy during spermiogenesis is still largely unknown. In the present study, we showed that the autophagy enhanced lipid droplets (LDs) formation during spermiogenesis in Chinese soft-shelled turtle, Pelodiscus sinensis. TEM and Oil Red O staining results found that the number and size of LDs within spermatid increased considerably during the process of spermiogenesis. RNA-Seq analysis revealed that autophagy was highly activated via the PI3K pathway during spermatogenesis. Inhibiting autophagy with 3-methyladenine (3-MA) significantly decreased testicular triglycerides (TGs) and fatty acid (FAs) content. In comparison with the control group, the number and size of LD within elongating spermatids was reduced significantly in the 3-MA group. Moreover, DGAT1, a diacylglycerol acyltransferase, which normally localize to the endoplasmic reticulum, was found to co-localize with LDs. Taken together, our results showed that FAs released through the autophagic degradation of germ-plasm was replenished LDs of spermatid, increasing LD number and size, during the process of spermiogenesis. These LDs facilitate long-term sperm storage in the epididymis of Chinese soft-shelled turtle.

18.
Dalton Trans ; 48(48): 17925-17935, 2019 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-31793567

RESUMO

Three novel copper(ii) complexes, Cu(L1)2 (1), Cu(L2)2·2DMF (2), and Cu(L3)2·2DMF (3), were synthesized using three aroylhydrazone ligands, (E)-2-hydroxy-N'-(1-(pyrazin-2-yl)ethylidene)benzohydrazide (HL1), (E)-3-hydroxy-N'-(1-(pyrazin-2-yl)ethylidene)benzohydrazide (HL2) and (E)-4-hydroxy-N'-(1-(pyrazin-2-yl)ethylidene)benzohydrazide (HL3). The complexes were characterized by elemental analysis, infrared (IR), and Ultraviolet-visible light (UV-vis) spectroscopy. The X-ray crystal structures of the complexes all possess a distorted octahedral coordination geometry. Both an absorption spectral titration and a competitive binding assay (ethidium bromide, 4',6-diamidino-2-phenylindole (DAPI), and methyl green) revealed that complexes 2 and 3 bind readily to calf thymus DNA (ctDNA) through intercalative and minor groove binding modes. Complexes 2 and 3 also exhibited oxidative cleavage of supercoiled plasmid DNA (pUC19) in the presence of ascorbic acid as an activator. Cytotoxicity studies showed that complexes 2 and 3 possessed high cytotoxicities toward the HeLa human cervical cancer cell line, but weak toxicities toward the L929 normal mouse fibroblast cell line. We therefore have reason to believe that complexes 2 and 3 both show potential as promising anticancer candidate drugs.

19.
J Am Chem Soc ; 141(49): 19404-19414, 2019 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-31794205

RESUMO

A major chemical challenge facing implementation of 225Ac in targeted alpha therapy-an emerging technology that has potential for treatment of disease-is identifying an 225Ac chelator that is compatible with in vivo applications. It is unclear how to tailor a chelator for Ac binding because Ac coordination chemistry is poorly defined. Most Ac chemistry is inferred from radiochemical experiments carried out on microscopic scales. Of the few Ac compounds that have been characterized spectroscopically, success has only been reported for simple inorganic ligands. Toward advancing understanding in Ac chelation chemistry, we have developed a method for characterizing Ac complexes that contain highly complex chelating agents using small quantities (µg) of 227Ac. We successfully characterized the chelation of Ac3+ by DOTP8- using EXAFS, NMR, and DFT techniques. To develop confidence and credibility in the Ac results, comparisons with +3 cations (Am, Cm, and La) that could be handled on the mg scale were carried out. We discovered that all M3+ cations (M = Ac, Am, Cm, La) were completely encapsulated within the binding pocket of the DOTP8- macrocycle. The computational results highlighted the stability of the M(DOTP)5- complexes.

20.
Artigo em Inglês | MEDLINE | ID: mdl-31794393

RESUMO

This paper presents a resonant cavity-based array design for piezoelectric micromachined ultrasonic transducers (PMUTs). The cavity depth is designed to ensure that its open end achieves a considerably smaller acoustic impedance than the surrounding PMUT cells. The interference acoustic wave generated between every two adjacent PMUT cells at the near surface of the array will take an easy path down to the cavity bottom. As such, the crosstalk effect among different adjacent cells in the array can be largely reduced. An equivalent circuit model of the proposed array is established for its design and optimization. In addition, the solutions for circuit parameters in the electromechanical domain are analytically derived and verified via FEM simulations. Given the low crosstalk effect achieved by the proposed array design, the output sensitivity of the proposed PMUTs can be improved by 259% compared with the traditional PMUTs with a high distribution density of the same size. The cavity-based array design and its model can be used for further advanced PMUT cell structures in other arrays to improve their performance.

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