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1.
Environ Sci Technol ; 2019 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-31442034

RESUMO

Metal contamination in soil, dust, and food matrices impacts the health of millions of people worldwide. During the past decades, various animal bioassays have been developed to determine relative bioavailability (RBA) of As, Pb, and Cd in contaminated soils, dust, and foods, which vary in operational approaches. This review discusses the strengths and weaknesses of different animal models (swine and mice), dosing schemes (single gavage dose, repeated gavage dose, daily repeated feeding, and free access to diet), and endpoints (blood, urine, and tissue) in metal-RBA measurement; compares metal-RBA obtained using mouse and swine bioassays, different dosing schemes, and different endpoints; and summarizes key findings on As-, Pb-, and Cd-RBA values in contaminated soils, dust, and foods. Future directions related to metal-RBA research are highlighted, including 1) comparison of metal-RBA determinations between different bioassays and different laboratories to ensure robust bioavailability data, 2) enhancing the metal-RBA database for contaminated dust and foods, 3) identification of physiological and physicochemical mechanisms responsible for variability in metal-RBA values, 4) formulation of strategies to decrease metal-RBA values in contaminated soils, dust, and foods, and 5) assessing the impacts of co-contaminants on metal-RBA measurement.

2.
J Med Case Rep ; 13(1): 272, 2019 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-31451109

RESUMO

BACKGROUND: The robot-assisted laparoscopic management of post-chemotherapy retroperitoneal metastasis and inferior vena cava tumor thrombus secondary to testicular cancer is a challenging task for urologists. CASE PRESENTATION: A pathological examination of a 36-year-old Caucasian man who had undergone a right radical orchiectomy showed mixed testicular germ cell cancer (70% embryonal cancer and 30% seminoma); he had undergone four prior courses of cisplatin, etoposide, and bleomycin chemotherapy and was found to have residual retroperitoneal enlarged lymph nodes close to the right renal hilum and a 9.8 cm inferior vena cava tumor thrombus (pT1, N2, M1, S2). Pre-surgical three-dimensional image reconstruction was performed based on contrast computed tomography data. The inferior vena cava tumor thrombus was found in the vena cava at the level of the celiac trunk and the inferior mesenteric artery. Our patient accepted treatment with robot-assisted laparoscopic retroperitoneal lymph node dissection with concomitant inferior vena cava thrombectomy and cava reconstruction on September 12, 2018. During the procedure, a drop-in robotic ultrasound probe was used to define the thrombus. Vena cavoscopy using a flexible ureteroscope found that the tumor thrombus adhered to the cava wall in all directions. The tumor thrombus was dissected free from the inferior vena cava lumen, and vena cava reconstruction was achieved using the da Vinci™ Si HD surgical system. The operative time was 550 minutes. The intraoperative estimated blood loss was 2300 ml. Intraoperative blood transfusions consisted of 10 units of red blood cells (Clavien-Dindo grade II). No Clavien-Dindo grade III or above perioperative complications occurred. The length of hospital stay was 7 days. Pathology revealed no viable cancer cells in any of the residual lymph node tissues or in the vena cava tumor thrombus. CONCLUSION: This is the first case of robot-assisted laparoscopic retroperitoneal lymph node dissection with concomitant inferior vena cava thrombectomy and reconstruction for metastatic mixed testicular germ cell cancer published to date. This complicated surgical procedure was facilitated by the innovative usage of three-dimensional image reconstruction for defining the vena cava tumor thrombus, a robotic ultrasound probe for intraoperatively defining the vena cava tumor thrombus, and vena cavoscopy using a flexible ureteroscope.

3.
Biosens Bioelectron ; 143: 111593, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31442750

RESUMO

Accurate and sensitive detection of the Pax-5a gene is of great importance in the early diagnosis and prognosis of acute leukaemia. Herein, a label-free electrochemical sensing system was proposed for the detection of the acute leukaemia Pax-5a gene based on enzyme-assisted signal amplification to generate abundant G-quadruplex/hemin DNAzyme. The presence of Pax-5a can open the hairpin probe (HP), which acts as a template. Under the action of the restriction enzymes Nt.BbvCI and Klenow fragment polymerase, the target gene Pax-5a is cycled to open the HP; On the other hand, a large number of G-quadruplex sequences are produced. The resulting G-quadruplex sequence is capable of forming the G-quadruplex/hemin complex on the surface of the electrode in the presence of hemin. The ultrasensitive label-free electrochemical detection of Pax-5a can be realized via the G-quadruplex/hemin complex-catalysed reduction of H2O2, and the detection limit was estimated to be as low as 4.6 fM. In addition, the biosensor has good specificity and stability, and also has excellent detection capabilities in a complex substrate environment. Therefore, the sensor shows great potential in bioanalysis and clinical diagnosis.

4.
World J Surg ; 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31367782

RESUMO

BACKGROUND AND AIM: Elucidating the mechanism of recurrent laryngeal nerve (RLN) injuries through intraoperative electromyographic (EMG) and laryngeal examination approaches may deepen our knowledge regarding its prevention strategies. To date, no studies have been reported on the mechanism of RLN injury caused by endoscopic thyroidectomy via bilateral areola approach (ETBAA). METHODS: Both intraoperative EMG profiles and postoperative laryngeal examination were used to investigate the mechanisms of RLN injury and compare the safety aspects between ETBAA and open thyroidectomy approach (OTA). RESULTS: This study examined 1420 nerves at risk. The mean follow-up period was 17 ± 4 (range 6-48) months. The incidence of vocal cord paralysis was 4.1% (59/1420). The number of cases with decreased EMG signals and vocal cord palsy was higher in ETBAA group than in OTA group (P < 0.05). The left RLNs in ETBAA group were at higher risk compared to the right nerves. CONCLUSIONS: The results of the current study indicate that ETBAA exhibits higher risk of RLN injury. The topic includes a video.

5.
J Agric Food Chem ; 67(30): 8382-8392, 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31271032

RESUMO

Staphylococcus aureus is a common pathogen that can cause life-threatening infections. Treatment of antibiotic-resistant S. aureus infection needs effective antibacterial agents. Thymol, a generally recognized safe natural compound, has potential as an alternative to treat S. aureus infections. However, the targets and mechanisms of action of thymol were not fully understood. Bioinformatics analysis showed that IolS, a predicted aldo-keto reductase (AKR) in S. aureus, could be a potential target of thymol. Isothermal titration calorimetry (ITC) analysis demonstrated that thymol directly binds IolS and amino acid residues (Y30 and L33) are essential for such binding. Deletion of IolS or mutation of Y30A and L33A reduced the bactericidal activity of thymol at the concentration of 200 µg/mL, suggesting that thymol mediates bactericidal activity via binding with IolS. Biochemical analysis showed that addition of thymol significantly increased AKR activity of IolS from 1.6 ± 0.1 to 2.4 ± 0.2 U (p < 0.05). The content of NADPH within S. aureus cells decreased significantly from 105 ± 5 to 72 ± 3 pmol/108 cells (p < 0.05) following thymol treatment at the concentration of 200 µg/mL. Importantly, addition of NADPH could alleviate the bactericidal effect of thymol on S. aureus, indicating that the depletion of NADPH is responsible for thymol-mediated bactericidal activity. Overall, these results demonstrated that thymol could directly bind IolS and increase its AKR activity, leading to the depletion of NADPH and bactericidal effect. AKR activity of IolS could be a promising target for the development of new antimicrobials.


Assuntos
Aldo-Ceto Redutases/antagonistas & inibidores , Antibacterianos/farmacologia , Proteínas de Bactérias/antagonistas & inibidores , NADP/metabolismo , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/enzimologia , Timol/farmacologia , Aldo-Ceto Redutases/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Humanos , Testes de Sensibilidade Microbiana , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/genética
6.
Nano Lett ; 19(8): 5277-5286, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31331173

RESUMO

The cytotoxic reactive oxygen species (ROS) generated by photoactivated sensitizers have been well explored in tumor therapy for nearly half a century, which is known as photodynamic therapy (PDT). The poor light penetration depth severely hinders PDT as a primary or adjuvant therapy for clinical indication. Whereas microwaves (MWs) are advantageous for deep penetration depth, the MW energy is considerably lower than that required for the activation of any species to induce ROS generation. Herein we find that liquid metal (LM) supernanoparticles activated by MW irradiation can generate ROS, such as ·OH and ·O2. On this basis, we design dual-functional supernanoparticles by loading LMs and an MW heating sensitizer ionic liquid (IL) into mesoporous ZrO2 nanoparticles, which can be activated by MW as the sole energy source for dynamic and thermal therapy concomitantly. The microwave sensitizer opens the door to an entirely novel dynamic treatment for tumors.

7.
Artif Cells Nanomed Biotechnol ; 47(1): 2662-2669, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31257936

RESUMO

Shikonin has been testified to wield the anti-tumor action in multiple cancers. But, the clout of Shikonin for gastric cancer (GC) is still inconclusive. The contemplation of this research undertook to disclose the impacts of Shikonin on GC progress meanwhile to uncover the conceivable mechanism. NCI-N87 cells were disposed by Shikonin at diverse concentration points. The trials of CCK-8, colony formation, flow cytometry and Transwell assays were executed for detecting the functions of Shikonin in NCI-N87 cells. The impacts of miR-195 on Shikonin-regulated PI3K/AKT pathway were estimated via western blot. The in vivo trial was detected by xenografts model assay. We found that Shikonin suppressed cell survival and triggered apoptosis in NCI-N87 cells. Additionally, Shikonin restrained cell migration, invasion and down-regulated MMP2, RhoA, ROCK1 and Vimentin expression in NCI-N87 cells. Furthermore, Shikonin notably inhibited PI3K/AKT signal pathway, but the restraining functions were repealed by miR-195 inhibition in NCI-N87 cells. The in vivo trial results revealed that Shikonin determinately impeded tumor formation. In conclusion, these results demonstrated that Shikonin prohibited NCI-N87 cells proliferation, migration, invasion, and accelerated apoptosis by inactivation of PI3K/AKT pathway. The findings maybe provide a fresh opinion for healing GC.

8.
Mikrochim Acta ; 186(8): 517, 2019 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-31280405

RESUMO

A fluorometric assay is described for the tumor suppressor gene p53. The method is based on strand displacement amplification on gold nanoparticles (GNPs). A FAM-labeled hairpin probe (HPP) is used that can hybridize to the GNP-confined linker strand, and the green fluorescence of the FAM label is quenched by the GNPs. In the presence of the p53 gene, it will hybridize with the HPP. This leads to fluorescence recovery. The primer then hybridizes with the opened HPP and induces the polymerization/displacement reactions. As a result, the hybridized p53 gene is released and, in turn, hybridizes with another HPP on the surface of the GNPs. This triggers the next round of hybridization/enzymatic polymerization/displacement reactions. This results in efficient strand displacement amplification and generates a substantially amplified signal. The method is referred to as GNP-HPP because it involves the use of GNPs and a HPP. The method allows the target DNA (p53) to be quantified down to 1.6 pM concentrations with a linear response in the 5 pM to 1 nM concentration range. In addition, mutant p53 genes can be easily distinguished from the wild-type gene. The method is highly sensitive, selective, and has a low background signal. Graphical abstract Schematic presentation of a chain hybridization signal amplification system (GNP-HPP) based on the use of gold nanoparticles (GNP) as a quenching source for the tumor suppressor gene p53 detection. The hairpin probe (HPP) having a 5'-end modified fluorophore was used as a signalling probe.

9.
J Sci Food Agric ; 99(12): 5586-5593, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31152446

RESUMO

BACKGROUND: Mono-, di- and oligosaccharides, polyhydric alcohols and lipids are three main types of plasticizers used to process food materials. In the present study, inulin, maltitol and lecithin were selected as representative oligosaccharide, polyhydric alcohol and lipid fat replacers, respectively. Their effects on the physicochemical properties of reduced-fat mozzarella cheese were evaluated. RESULTS: Lecithin reduced the hardness and increased the degree of free oil released. Inulin and lecithin decreased the hydrophobic interaction of reduced-fat cheese. Maltitol improved the elasticity of the reduced-fat cheese and increased the hydrophobic interaction within the casein matrix. Maltitol-added cheese had a lower glass transition temperature (Tg ) than the other cheeses. Maltitol significantly improved the stretchability of the reduced-fat cheese. CONCLUSION: The results obtained in the present study suggest that maltitol is an effective fat replacer in reduced-fat mozzarella cheese and might enhance the cheese's functional properties. The Tg of cheese was related to the water and fat content, fat replacer addition and cross-linking degree of casein. The relationship between Tg and the physicochemical properties of cheese will be studied in further research. © 2019 Society of Chemical Industry.


Assuntos
Queijo/análise , Substitutos da Gordura/análise , Aditivos Alimentares/análise , Inulina/análise , Lecitinas/análise , Maltose/análogos & derivados , Plastificantes/análise , Álcoois Açúcares/análise , Animais , Caseínas/análise , Bovinos , Manipulação de Alimentos , Dureza , Maltose/análise
10.
Gigascience ; 8(6)2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-31216035

RESUMO

BACKGROUND: Accurate and complete reference genome assemblies are fundamental for biological research. Cucumber is an important vegetable crop and model system for sex determination and vascular biology. Low-coverage Sanger sequences and high-coverage short Illumina sequences have been used to assemble draft cucumber genomes, but the incompleteness and low quality of these genomes limit their use in comparative genomics and genetic research. A high-quality and complete cucumber genome assembly is therefore essential. FINDINGS: We assembled single-molecule real-time (SMRT) long reads to generate an improved cucumber reference genome. This version contains 174 contigs with a total length of 226.2 Mb and an N50 of 8.9 Mb, and provides 29.0 Mb more sequence data than previous versions. Using 10X Genomics and high-throughput chromosome conformation capture (Hi-C) data, 89 contigs (∼211.0 Mb) were directly linked into 7 pseudo-chromosome sequences. The newly assembled regions show much higher guanine-cytosine or adenine-thymine content than found previously, which is likely to have been inaccessible to Illumina sequencing. The new assembly contains 1,374 full-length long terminal retrotransposons and 1,078 novel genes including 239 tandemly duplicated genes. For example, we found 4 tandemly duplicated tyrosylprotein sulfotransferases, in contrast to the single copy of the gene found previously and in most other plants. CONCLUSION: This high-quality genome presents novel features of the cucumber genome and will serve as a valuable resource for genetic research in cucumber and plant comparative genomics.

11.
Biomaterials ; 214: 119223, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31174065

RESUMO

Nanozymes with excellent enzyme-mimicking catalytic property are playing an increasingly significant role in tumor diagnosis and therapy. Fe-metal organic framework nanoparticles (MIL-101(Fe) NPs) are prepared as nanozymes to generate reactive oxygen species (ROS) and induce cancer cell death by catalyzing endogenous substances in tumor microenvironment. Abundant stimuli-responsive hydroxyl radicals (·OH) are accelerated to generate in the presence of microwave irradiation, realizing microwave enhancing dynamic therapy (MEDT). Moreover, MIL-101(Fe) NPs possess biodegradability and bioresponsibility, which exhibit favourable properties of metabolism and non-toxic accumulation comparing with inorganic nanozymes. Fluorescent gold nanoclusters (BSA-Au NCs) are rapidly coupled with the surface of MIL-101(Fe) NPs to obtain MIL-101(Fe)@BSA-AuNCs NPs. MIL-101(Fe)@BSA-AuNCs NPs with magnetic resonance imaging (MRI) and fluorescent imaging (FI) not only image accurately for the site of tumor, but also monitor dynamic distribution process of MIL-101(Fe) in vivo. The signal intensity of FI and MRI reaches maximum at 1 h in the liver and 5 h in the tumor. Ionic liquid (IL) is also loaded into MIL-101(Fe)@BSA-AuNCs NPs as microwave sensitive reagents for microwave thermal therapy (MTT). This work synthesizes the nanozymes that possess degradability, microwave sensitivity and dual-mode imaging to achieve the combination of MTT and MEDT against tumor. Experiment result in vivo confirms that the kill rate of tumor is up to 96.65%, showing an outstanding anti-tumor efficacy.

12.
J Econ Entomol ; 2019 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-31219570

RESUMO

Superoxide dismutase (SOD) is an antioxidant metalloenzyme that catalyzes the dismutation of the superoxide anion O2- to O2 and H2O2. Many studies have focused on the role of SOD in response to abiotic stress, but its role during biotic stress, such as changes in organismal population density, has rarely been investigated. The oriental armyworm, Mythimna separata, is an economically important pest that exhibits phenotypic changes in response to population density. Solitary and gregarious phases occur at low and high population density, respectively. To examine the role of SODs in response to population density stress, we cloned two genes encoding SOD, MsCuZnSOD and MsMnSOD, and compared their expression in solitary and gregarious phases of M. separata. The MsCuZnSOD and MsMnSOD ORFs were 480 and 651 bp and encoded predicted protein products of 159 and 216 amino acids, respectively. The two SODs contained motifs that are typical of orthologous proteins. Real-time PCR indicated that the two SOD genes were expressed throughout developmental stages and were significantly upregulated in more mature stages of gregarious M. separata. Expression of the two SOD genes in various tissues of sixth-instar larvae was higher in gregarious versus solitary insects. Furthermore, expression of the SOD genes was significantly upregulated in response to crowding in solitary individuals, but suppressed in gregarious insects subjected to isolation. Collectively, these results suggest that population density may be key factor in the induction of SOD genes in M. separata.

13.
Environ Int ; 130: 104875, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31200159

RESUMO

The robustness of in vitro bioaccessibility assays to predict oral relative bioavailability (RBA) of multiple metals in contaminated soils requires validation using additional soil samples. In this study, 11 contaminated soils from mining/smelting areas were analyzed for As-, Cd-, and Pb-RBA using a mouse bioassay and metal bioaccessibility via the UBM gastric phase assay. Metal-RBA varied considerably among soils, with As-RBA (2.5-23%, mean 12%) being generally lower than Cd-and Pb-RBA (3.4-88 and 3.3-59%, mean 42 and 28%), due to higher proportions of As in the residual fractions. Metal-RBA generally decreased with increasing metal concentrations probably due to reduced labile metal fractions. In addition, strong negative correlations were observed between total Fe with As-, Cd-, and Pb-RBA (R2 = 0.46-0.77), suggesting the role of Fe in controlling metal-RBA in soils. Like RBA, metal bioaccessibility by the UBM assay also varied among samples. However, strong in vivo-in vitro correlations (IVIVCs) were observed between metal-RBA and bioaccessibility (R2 = 0.52-0.81). Further, there were little differences when As-, Cd-, and Pb-IVIVCs established using soils from this study and soils pooled from literature were compared, suggesting the robustness of the UBM assay to predict metal-RBA in contaminated soils.

14.
Nanoscale ; 11(21): 10190-10197, 2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31112179

RESUMO

Herein we report a nanorod couple heterostructure made of dual semiconductors, in which two parallelly aligned ZnSe nanorods are connected by the growth of ZnS on both end and side facets, producing hetero-ZnS (short arms)-ZnSe (long arms)/ZnS shell nanorod couples. As evidenced by electronic structure studies, both experimental and theoretical, such core/shell nanorod couple heterostructures can act as a platform to precisely tailor the quantum confinement of charge carriers between the constituting components within a single nano-object, generating blue fluorescence after the overgrowth of an alloyed ZnCdS layer on the heterostructures. We foresee the mechanistic insights gained and electronic structures revealed in this work would shed light on the rational design of more complex heterostructures with novel functionalities.

15.
Nanoscale ; 11(21): 10183-10189, 2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31112189

RESUMO

With extensive investigations involving liquid metals (LMs), Ga-based LMs have attracted increasing attention from biomedical researchers because of their good biocompatibility, ideal fluidity, and high thermal conductivity. LMs employed in cancer treatment suffer from high surface tension, thereby yielding unstable nanoparticles (NPs). Here, ZrO2 is coated onto LM NPs to form a stable core-shell nanostructure. In particular, LM NPs coated with ZrO2 and modified by PEG (LM@pZrO2 NPs) still maintain favorable flexibility, which is beneficial for cellular uptake. With regard to the photothermal properties of LM, LM@pZrO2 NPs rapidly warm up and emit the requisite amount of heat under NIR laser radiation. It is confirmed that LM@pZrO2 NPs are more effectively internalized by cells and are beneficial for tumor photothermal therapy. This research provides a coating strategy to fabricate a stable and flexible core-shell LM nanostructure, making it a promising vehicle for nanotheranostics.

16.
Water Res ; 160: 118-129, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31136846

RESUMO

Microbes drive ecosystems and their viruses manipulate these processes, yet the importance of tidal functioning on the estuarine viruses and microbes remains poorly elucidated. Here, an integrative investigation on tidal patterns in viral and microbial communities and their inherent interactions over an entire spring-neap tidal cycle was conducted along a macrotidal subtropical estuary. The viral and microbial abundances oscillated significantly over the tidal cycle with relatively higher abundances observed at spring tide compared to neap tide. The distinct tidal dynamic patterns in bacterial production and community composition were tightly associated with the variations in viral infection, production and decay, revealing the tide-driven interactions between viruses and microbes. Concurrent with the higher viral decay but lower bacterial abundance and inhibited bacterial metabolism during the neap tide, lower gross viral production was coupled with a synchronous switching from viral lytic to lysogenic infection induced by the loss of viral infection efficiency and the transition from marine to freshwater bacterial populations triggered by tidal mixing. Our results highlighted the major tidal impact on the microbial dynamics through virus-host interactions, with cascading effects, neglected so far, on estuarine biogeochemical cycles.

17.
Technol Health Care ; 27(S1): 263-272, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31045545

RESUMO

BACKGROUND: Traditional cancer treatments such as surgery, radiation, and chemotherapy destroy both cancer and normal cells, which limit their clinical application. It is difficult to achieve the best results for any liver cancer patients using any single treatment method. Gene therapy for HCC demands non-invasive, efficient, targeted and safe gene transfection strategies. OBJECTIVE: In this study, a nonviral shRNA gene delivery system utilizing a combination of PEI, US, and NBs was developed for targeting survivin in liver Cancer. METHODS AND RESULTS: The PEI-shRNA-NBs cumulated in the tumor tissue because of the EPR effect. By exposure to the US, micelles shRNA may be released from PEI-shRNA-NBs in tumor tissues and the shRNA then transmitted efficiently to cancer cells. Considerably enhanced therapeutic outcome was obtained with the gene silencing effect enhanced. CONCLUSIONS: PEI-shRNA-NBs possess the potential to become promising tools intended for shRNA delivery.

18.
Environ Sci Technol ; 53(10): 5717-5724, 2019 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-31009209

RESUMO

Although strong in vivo-in vitro correlations (IVIVCs) between relative bioavailability (RBA) and bioaccessibility of soil Pb were well reported, knowledge on the fractions of bioaccessible Pb in simulated gastrointestinal (GI) fluids that are available for absorption into the systemic circulation is limited. Here, Pb-RBA in 14 Pb-contaminated soils were assessed using an in vivo mouse bioassay and compared to Pb bioaccessibility by the gastrointestinal phase of the UBM (Unified Bioaccessibility research group of Europe (BARGE) Method) in vitro assay with and without 0.45 µm filtration of GI fluid. Results showed good IVIVC between Pb-RBA and Pb bioaccessibility without filtration ( r 2 = 0.62), while Pb bioaccessibility with filtration provided a poor correlation with Pb-RBA ( r 2 = 0.16). This suggested that besides dissolved Pb ions, Pb-complexes formed in the UBM gastrointestinal fluid might also contribute to bioavailable Pb. To ascertain this, DGT (diffusive gradients in thin-films) devices which can measure both Pb2+ ions and labile inorganic and organic Pb-complexes were introduced to the UBM fluids to measure Pb DGT-bioaccessibility, which showed strong correlation to Pb-RBA ( r 2 = 0.71). With increasing diffusive gel thickness which could enhance release of Pb ions from Pb-complexes, Pb DGT-bioaccessibility increased by 3.4-5.7 times, while inclusion of dialysis membrane within DGT devices significantly decreased Pb DGT-bioaccessibility by inhibiting diffusion of Pb complexes to binding gel. These results confirmed the contribution of Pb-complexes to Pb bioavailability, providing new insights to Pb bioavailability.

19.
Biomed Pharmacother ; 114: 108815, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30954890

RESUMO

This study aimed to explore mechanisms of the effects of hydroxysafflor yellow A (HSYA) on neural stem cells (NSCs) after heat stress (HS). Rat NSCs cells were cultured at 42 °C to impose heat stress. Cell counting kit-8 and Edu assay were used to analyze NSC proliferation. Annexin V/PI apoptosis kit was used to detect NSC apoptosis. Expression and phosphorylation of autophagy and apoptosis-associated proteins were determined by western blotting. We showed that HSYA significantly promoted proliferation and attenuated apoptosis of NSCs after heat stress. HSYA also increased Bcl-2 expression but decreased the expression of Bax and cleaved caspase-3 in NSCs induced by heat stress. In addition, HSYA decreased p38 and Hsp27-78 phosphorylation and MK-2 expression after heat stress, which was consistent with NSCs treated with SB203850 treatment or p38 knockdown. Furthermore, we demonstrated that heat stress increased LC3-II expression and mTOR phosphorylation, and decreased the expression of p62 in NSCs, while HSYA, SB203850 treatment or p38 knockdown reversed these alterations. In conclusion, HSYA significantly reversed the apoptosis and autophagy of NSCs induced by heat stress (P < 0.05), via downregulating MK2 expression and p38 and Hsp27-78 phosphorylation.


Assuntos
Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Chalcona/análogos & derivados , Resposta ao Choque Térmico/efeitos dos fármacos , Células-Tronco Neurais/efeitos dos fármacos , Quinonas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Animais , Linhagem Celular , Chalcona/farmacologia , Proteínas de Choque Térmico/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Células-Tronco Neurais/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Ratos
20.
Nat Plants ; 5(5): 512-524, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30962512

RESUMO

The endosomal sorting complex required for transport (ESCRT) machinery has been well documented for its function in endosomal sorting in eukaryotes. Here, we demonstrate an up-to-now unknown and non-endosomal function of the ESCRT component in plants. We show that FYVE DOMAIN PROTEIN REQUIRED FOR ENDOSOMAL SORTING 1 (FREE1), a recently identified plant-specific ESCRT component essential for multivesicular body biogenesis, plays additional functions in the nucleus in transcriptional inhibition of abscisic acid (ABA) signalling. Following ABA treatment, SNF1-related protein kinase 2 (SnRK2) kinases phosphorylate FREE1, a step requisite for ABA-induced FREE1 nuclear import. In the nucleus, FREE1 interacts with the basic leucine zipper transcription factors ABA-RESPONSIVE ELEMENTS BINDING FACTOR4 and ABA-INSENSITIVE5 to reduce their binding to the cis-regulatory sequences of downstream genes. Collectively, our study demonstrates the crosstalk between endomembrane trafficking and ABA signalling at the transcriptional level and highlights the moonlighting properties of the plant ESCRT subunit FREE1, which has evolved unique non-endosomal functions in the nucleus besides its roles in membrane trafficking in the cytoplasm.


Assuntos
Ácido Abscísico/fisiologia , Proteínas de Arabidopsis/fisiologia , Complexos Endossomais de Distribuição Requeridos para Transporte/fisiologia , Reguladores de Crescimento de Planta/fisiologia , Proteínas de Transporte Vesicular/fisiologia , Transporte Ativo do Núcleo Celular/fisiologia , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Núcleo Celular/metabolismo , Fosforilação , Proteínas de Transporte Vesicular/metabolismo
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