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1.
Mol Pharm ; 2020 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-32401529

RESUMO

Despite the wide utilization of amorphous solid dispersions (ASDs) for formulating poorly water-soluble drugs, fundamental understanding of the structural basis behind their stability and dissolution behavior is limited. This is largely due to the lack of high-resolution structural tools for investigating multi-component and amorphous systems in the solid state. In this study, we present what is likely the first publication quantifying the molecular interaction between drug and polymer in ASDs at an angstrom level by utilizing 19F magic angle spinning (MAS) nuclear magnetic resonance (NMR) techniques. A variant of 19F-13C Rotational Echo and Double Resonance (REDOR) technique was developed to quantify interatomic distances by implementing a super-cycled symmetry-based recoupling schedule and synchronized simultaneous detection. We successfully deployed the technique to identify "head-to-head" and "head-to-tail" packing of crystalline posaconazole (POSA). To probe molecular interactions between POSA and hypromellose acetate succinate (HPMCAS) in the dispersion, as a major goal of this study, two-dimensional (2D) 1H-19F correlation experiments were performed. The approach facilitated observation of inter-molecular hydrogen-to-fluorine contacts between the hydroxyl group of the polymer and the difluorophenyl group of the drug substance. Atomic distance measurement, utilizing the developed 19F-13C REDOR technique, revealed the close proximity of 13COH-19F at 4.3 Å. Numerical modeling analysis suggested a possible hydrogen bonding interaction between the polymer O-H group as an acceptor and POSA fluorine (O-H···F) or difluorophenyl ring (O-H···Ph) as a donor. These 19F MAS NMR techniques, including 2D 19F-1H hetero-nuclear correlation and 19F-13C atomic distance measurement, may shed light on the nature (i.e. type and strength) of drug-polymer interactions in ASDs and offers a new high-resolution analytical protocol for probing the microstructure of amorphous pharmaceutical materials.

2.
J Environ Manage ; 267: 110651, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32349958

RESUMO

A healthy aquatic ecosystem plays an important role in the operation of nature and the survival of human beings. Understanding the mechanism of its interaction with the habitat process is conducive to formulating targeted ecological recovery plans. In this study, fish and macroinvertebrates were collected from 49 investigation sites in the Weihe River basin, China, during periods of the summer and the autumn of 2017. Cluster analysis and canonical correlation analysis (CCA) were used to analyze the similarity of community distribution of fish and macroinvertebrates and their response to environmental variables. The biological integrity index of fish (F-IBI) and benthic-macroinvertebrate (B-IBI) was introduced to evaluate the aquatic ecological health. The results showed that fish communities were more coherent than macroinvertebrate communities. The distinguished response to ecological factors was identified for fish and macroinvertebrates. The ecological factors of total nitrogen, conductivity and river width have significant effects on both fish and macroinvertebrate communities. In addition, the fish community was significantly influenced by chlorine, fluorine, pH and flow velocity, while the macroinvertebrate community was significantly influenced by bicarbonate and water depth. The differences in community structure and response to ecological factors between communities were amplified in their environmental quality scores. Although F-IBI and B-IBI tend to be consistent temporally, the correlation is not significant. B-IBI showed decreasing gradient of ecological health status in the downstream area, while F-IBI tended to be different across river systems, which further illustrated the differences in the response of fish and macroinvertebrates to environmental variables.


Assuntos
Ecossistema , Invertebrados , Animais , Biota , China , Monitoramento Ambiental
3.
Mol Pharm ; 2020 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-32392076

RESUMO

In solid dosage formulations, probing intermolecular interactions between active pharmaceutical ingredients (APIs) and polymeric excipients, which have a mechanistic impact on physical stability as well as bioavailability, remains a challenge. In recent years, solid-state NMR spectroscopy has been demonstrated to be a powerful tool to provide structural details with an atomic resolution of therapeutic organic compounds and formulation products. However, conventional 13C-detected techniques often suffer from poor resolution and low sensitivity due to the disordered structure of certain materials such as amorphous pharmaceuticals and 13C natural abundance, hindering in-depth investigations. In this study, we utilize the magic angle spinning (MAS) technique with ultrafast speeds (UF-MAS: νR = 60 and 110 kHz) and demonstrate the enabled methods with 1H detection to study the amorphous molecular complex of rafoxanide and povidone in the solid state. The downfield shift of the RAF amide proton, resolved under UF-MAS, and its correlations with aliphatic protons of PVP, serve as strong evidence of the existence of intermolecular hydrogen bonding. Two-dimensional (2D) 1H-detected 1H{13C} and 1H-1H correlation experiments, interestingly, exhibit distinct API-polymer interactions in the spray-dried amorphous solid dispersions (ASDs), utilizing aqueous and organic cosolvents and organic solvents mixtures. The rich intermolecular interactions in the aqueously prepared ASDs presumably contribute to the physical stability, and the interactions are retained in the solution state to maintain supersaturation for an enhanced dissolution profile. This study presents the first application of UF-MAS NMR characterization of therapeutic solid dosages at a spinning frequency of 110 kHz and uncovers the molecular mechanisms of solvent-mediated pharmaceutical dispersions.

4.
Artigo em Inglês | MEDLINE | ID: mdl-32349514

RESUMO

In women who conceived with or without assisted reproduction, we evaluated endothelial function by EndoPATTM [Reactive Hyperemia Index (RHI)], circulating numbers of endothelial cells (CEC) and endothelial progenitor cells (EPC), and their function before, during and after pregnancy. IVF pregnancies were stratified by method of conception and corpus luteum (CL) number-controlled ovarian stimulation (>1 CL) or programmed (0 CL) cycles, and spontaneous, singleton pregnancies (1 CL). We observed: (1) comparable gestational decline of RHI in the three participant groups secondary to gestational rise of baseline, pre-occlusion pulse wave amplitude (PWA) incorporated into the RHI calculation by EndoPATTM software; (2) progressive rise in "normalized" RHI throughout pregnancy (calculated by substituting pre-pregnancy baseline, pre-occlusion PWA into the RHI equation), greater in spontaneous conception versus IVF cohorts; (3) similar gestational increase of maximum PWA and time to maximum PWA after the ischemia stimulus among the three participant groups; (4) modest gestational increase of ischemia response (reactive hyperemia) in the spontaneous conception group, and no change or significant decline, respectively, in women who conceived using programmed or controlled ovarian stimulation cycles; (5) enhanced basal nitric oxide production by early (primitive) outgrowth EPC during pregnancy in women who conceived spontaneously, but not through IVF; and (6) gestational increase in CEC in all three participant cohorts, more pronounced in women who conceived by IVF using programmed cycles. On balance, the evidence supported enhanced endothelial function during pregnancy in spontaneous conceptions, but less so in IVF pregnancies using either controlled ovarian stimulation or programmed cycles.

5.
J Phys Chem B ; 2020 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-32378905

RESUMO

Crystalline and amorphous materials usually possess distinct physicochemical properties due to major variations in long-range and local molecular packings. Enhanced fundamental knowledge of the molecular details of crystalline-to-amorphous interconversions is necessary to correlate the intermolecular structure to material properties and functions. While crystal structures can be readily obtained by X-ray crystallography, the microstructure of amorphous materials has rarely been explored due to a lack of high-resolution techniques capable of probing local molecular structures. Moreover, there is increasing interest in understanding the molecular nature of amorphous solids in pharmaceutical sciences due to the widespread utilization of amorphous active pharmaceutical ingredients (APIs) in pharmaceutical development for solubility and bioavailability enhancement. In this study, we explore multidimensional 13C and 19F magic angle spinning (MAS) NMR spectroscopy to study the molecular packing of amorphous posaconazole (POSA) in conjunction with the crystalline counterpart. Utilizing methods integrating homonuclear and heteronuclear 1H, 13C, and 19F correlation spectroscopy and atomic 19F-to-13C distance measurements, we identified the major differences in molecular packing between crystalline and amorphous POSA. The intermolecular "head-to-head" interaction along the molecule's major axis, as well as the "head-to-tail" molecular packing perpendicular to the major axis in POSA crystals, was recapitulated by MAS NMR. Furthermore, critical intermolecular distances in the crystal lattice were determined. Most importantly, the head-to-tail contact of two neighboring molecules was found to be preserved in amorphous POSA, suggesting localized molecular order, whereas crucial interactions for head-to-head packing are absent in the amorphous form resulting in long-range disorder. Our study, likely one of the first documented examples, provides molecular-level structural details to understand the molecular mechanism of crystalline-to-amorphous conversion of fluorine-containing drug substances occurring in drug processing and development and establish a high-resolution experimental protocol for investigating amorphous materials.

6.
Virol Sin ; 2020 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-32430872

RESUMO

Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease with high mortality (12%-30%). The mechanism by which the SFTS bunyavirus (SFTSV) causes severe illness remains unclear. To evaluate the phenotypic and functional characteristics of the NK cell subsets in SFTS patients, twenty-nine SFTS patients were sequentially sampled from admission until recovery. Phenotypic and functional characteristics of NK cell subsets in circulating blood were analysed via flow cytometry. Then, correlations between NK cell subset frequencies and the SFTS index (SFTSI) were evaluated in all SFTS patients (15 mild, 14 severe) upon admission. The frequencies of CD56dimCD16+ NK cells were greatly decreased in early SFTSV infection and were negatively correlated with disease severity. Additionally, higher Ki-67 and granzyme B expression and relatively lower NKG2A expression in CD56dimCD16+ NK cells were observed in acute infection. Moreover, the effector function of CD56dim NK cells was increased in the acute phase compared with the recovery phase in nine severe SFTS patients. Additionally, interleukin (IL)-15, interferon (IFN)-α, IL-18 and IFN-γ secretion was markedly increased during early infection. Collectively, despite depletion of CD56dimCD16+ NK cells, activation and functional enhancement of CD56dimCD16+ NK cells were still observed, suggesting their involvement in defence against early SFTSV infection.

8.
Diabetes Metab Res Rev ; : e3319, 2020 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-32233013

RESUMO

BACKGOUND: To figure out whether diabetes is a risk factor influencing the progression and prognosis of 2019 novel coronavirus disease (COVID-19). METHODS: A total of 174 consecutive patients confirmed with COVID-19 were studied. Demographic data, medical history, symptoms and signs, laboratory findings, chest computed tomography (CT) as well the treatment measures were collected and analysed. RESULTS: We found that COVID-19 patients without other comorbidities but with diabetes (n = 24) were at higher risk of severe pneumonia, release of tissue injury-related enzymes, excessive uncontrolled inflammation responses and hypercoagulable state associated with dysregulation of glucose metabolism. Furthermore, serum levels of inflammation-related biomarkers such as IL-6, C-reactive protein, serum ferritin and coagulation index, D-dimer, were significantly higher (P < .01) in diabetic patients compared with those without, suggesting that patients with diabetes are more susceptible to an inflammatory storm eventually leading to rapid deterioration of COVID-19. CONCLUSIONS: Our data support the notion that diabetes should be considered as a risk factor for a rapid progression and bad prognosis of COVID-19. More intensive attention should be paid to patients with diabetes, in case of rapid deterioration.

9.
Wei Sheng Yan Jiu ; 49(1): 98-131, 2020 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-32290922

RESUMO

OBJECTIVE: To study the effect of curcumin on the expression of glucose regulated protein 78 kD(GRP78) and cysteinyl aspartate specific proteinase-12(caspase-12) of myocardial endoplasmic reticulum stress related factors in type 2 diabetes rats. METHODS: Type 2 diabetes rats model was established by high-fat drink feeding and one-time intraperitoneal injecting streptozotocin(35 mg/kg). After model rats were built, rats was randomly divided into diabetic model group and low dose of curcumin group(200 mg/kg), high dose of curcumin group(400 mg/kg) and captopril group(60 mg/kg) with 10 rats in each group. The rats in each group were ig administered with corresponding drugs once a day. Continuous administration for 12 w. The levels of fasting blood glucose(FBG) and lactate dehydrogenase(LDH), electrocardiogram and heart weight index(HWI) were measured respectively. The myocardial pathological changes were observed by HE staining. The levels of collagen fiber expression in myocardial tissue were performed by Masson staining. The protein expression levels of GRP78 and caspase-12 in myocardium of rats were observed by immunohistochemistry. RESULTS: The result showed that compared with control group, the levels of FBG and LDH of serum were increased obviously, HWI was increased, myocardial cells were hypertrophy, the collagen fibers of intercellular space of cell were increased, the protein expressions of GRP78 and caspase-12 of myocardium were increased in rats, myocardial cell apoptosis was increased in the model group(P<0. 05). Compared with model group, FBG and LDH levels and HWI were reduced, the collagen fiber of intercellular space were decreased, the protein expression levels of GRP78 and caspase-12 were lowered in high dose of curcumin group(P<0. 05). CONCLUSION: It indicates that Cur defends myocardium tissue in type 2 diabetes rats, which may be related to decreasing the level of blood glucose and the protein expressions of GRP78 and caspase-12, and blocking the ERS-initiated apoptotic.

10.
Sci Rep ; 10(1): 6617, 2020 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-32313148

RESUMO

Lymphocytes are some of the most motile cells of vertebrates, constantly navigating through various organ systems. Their specific positioning in the body is delicately controlled by site-specific directional cues such as chemokines. While it has long been suspected that an intrinsic molecular pilot, akin to a ship's pilot, guides lymphocyte navigation, the nature of this pilot is unknown. Here we show that the TIPE (TNF-α-induced protein 8-like) family of proteins pilot lymphocytes by steering them toward chemokines. TIPE proteins are carriers of lipid second messengers. They mediate chemokine-induced local generation of phosphoinositide second messengers, but inhibit global activation of the small GTPase Rac. TIPE-deficient T lymphocytes are completely pilot-less: they are unable to migrate toward chemokines despite their normal ability to move randomly. As a consequence, TIPE-deficient mice have a marked defect in positioning their T lymphocytes to various tissues, both at the steady-state and during inflammation. Thus, TIPE proteins pilot lymphocytes during migration and may be targeted for the treatment of lymphocyte-related disorders.

11.
Plant Physiol ; 183(1): 358-370, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32139475

RESUMO

N-terminal (Nt) acetylation (NTA) is an ample and irreversible cotranslational protein modification catalyzed by ribosome-associated Nt-acetyltransferases. NTA on specific proteins can act as a degradation signal (called an Ac/N-degron) for proteolysis in yeast and mammals. However, in plants, the biological relevance of NTA remains largely unexplored. In this study, we reveal that Arabidopsis (Arabidopsis thaliana) SIGMA FACTOR-BINDING PROTEIN1 (SIB1), a transcription coregulator and a positive regulator of salicylic acid-primed cell death, undergoes an absolute NTA on the initiator Met; Nt-acetyltransferase B (NatB) partly contributes to this modification. While NTA results in destabilization of certain target proteins, our genetic and biochemical analyses revealed that plant NatB-involved NTA instead renders SIB1 more stable. Given that the ubiquitin/proteasome system stimulates SIB1 degradation, it seems that the NTA-conferred stability ensures the timely expression of SIB1-dependent genes, mostly related to immune responses. Taking our findings together, here we report a noncanonical NTA-driven protein stabilization in land plants.

12.
J Biol Chem ; 295(16): 5484-5495, 2020 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-32198183

RESUMO

The transcription factor forkhead box P3 (FOXP3) is a biomarker for regulatory T cells and can also be expressed in cancer cells, but its function in cancer appears to be divergent. The role of hepatocyte-expressed FOXP3 in hepatocellular carcinoma (HCC) is unknown. Here, we collected tumor samples and clinical information from 115 HCC patients and used five human cancer cell lines. We examined FOXP3 mRNA sequences for mutations, used a luciferase assay to assess promoter activities of FOXP3's target genes, and employed mouse tumor models to confirm in vitro results. We detected mutations in the FKH domain of FOXP3 mRNAs in 33% of the HCC tumor tissues, but in none of the adjacent nontumor tissues. None of the mutations occurred at high frequency, indicating that they occurred randomly. Notably, the mutations were not detected in the corresponding regions of FOXP3 genomic DNA, and many of them resulted in amino acid substitutions in the FKH region, altering FOXP3's subcellular localization. FOXP3 delocalization from the nucleus to the cytoplasm caused loss of transcriptional regulation of its target genes, inactivated its tumor-inhibitory capability, and changed cellular responses to histone deacetylase (HDAC) inhibitors. More complex FKH mutations appeared to be associated with worse prognosis in HCC patients. We conclude that mutations in the FKH domain of FOXP3 mRNA frequently occur in HCC and that these mutations are caused by errors in transcription and are not derived from genomic DNA mutations. Our results suggest that transcriptional mutagenesis of FOXP3 plays a role in HCC.

13.
Artigo em Inglês | MEDLINE | ID: mdl-32189416

RESUMO

This study was conducted to investigate the effect of grape seed procyanidins (GSP) on growth performance, digestive enzyme activity, antioxidant enzyme activity and mRNA expression in weanling piglets. A total of 96 piglets (Pietrain × Large White) with an average initial body weight (BW) of 8.4 ± 1.7 kg were weaned at 28 days, and randomly divided into 4 groups. Four groups of animals were fed with a basic diet supplemented with various doses of GSP (0, 40, 70 and 100 mg/kg respectively) during the 28-day treatment period. The results showed that the group receiving 40 mg/kg GSP significantly increased the average daily gain (ADG, p < .05) and decrease the feed/gain ratio (F/G, p < .05). Interestingly, the incidence of diarrhoea was significantly reduced in the groups of 40 and 70 mg/kg GSP, but it was increased in the group of 100 mg/kg GSP. Subsequent biochemical studies indicated that dietary GSP significantly increased the activities of digestive enzymes and antioxidant enzymes, including amylase (Amy), lipase(LPS, p < .05), glutathione peroxidase activity (GSH-Px, p < .05), superoxide dismutase activity (SOD, p < .05) and total antioxidant capacity (T-AOC, p < .05) in serum, liver and muscle, increased the expression of GSH-Px, SOD and CAT genes (p < .05) in the liver, and decreased the level of malondialdehyde (MDA, p < .05) in serum, liver and muscle. Taken together, these studies revealed that low GSP supplement in diets can improve growth performance of weaned piglets, which is associated with increased digestive and antioxidant enzyme activities and enhanced resistance to weanling stress.

14.
Colloids Surf B Biointerfaces ; 190: 110896, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32114270

RESUMO

Magnetic fluid hyperthermia has been one clinical treatment method in malignancy on account of the sufficient heat generation, which originates from hysteresis loss of magnetic nanomedicine in alternating magnetic field. Magnetic nanomedicine can also be employed as drug carrier for chemotherapy. Nevertheless few magnetic nanocarries has been approved in clinic, owing to the high pharmaceutical demand. For broadening the clinical application of current magnetic nanomedicine, novel magnetic hydrogel complex (DOX@FMT-MC) constituted by Doxorubicin, Ferumoxytol and Medical Chitosan was produced for hyperthermia and chemo synergistic therapy. The three materials were approved in clinic. Heat induction in vitro and rheology mesurements suggested this complex succeed in transforming into physical hydrogel when reaching hyperthermia temperature in alternating magnetic field. Drug release experiment implied the complex has the temperature-dependent slow drug release behaviour. Cell apoptosis assay presented that DOX@FMT-MC complex gave enhanced synergistic efficacy with 32.4 % on colon carcinoma cell treatment in vitro, compared to other therapeutic groups. Heat induction in mice subcutaneous xenografted tumour demonstrated the better heating performance of the complex than that of DOX@FMT. The novel hydrogel complex incorporated with three clinical available drugs promises the great potential in tumour synergistic treatment, motivating the clinical indication development of magnetic nanomedicine.

15.
EBioMedicine ; 52: 102660, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32062357

RESUMO

BACKGROUND: Circular RNAs (circRNAs) have been reported to be involved in central nervous system (CNS) diseases and to have a close connection with neuronal development. However, the role of circRNAs in neural stem cell (NSC) differentiation and the treatment of ischaemic stroke remains unknown. METHODS: Ischaemic stroke was induced in mice using transient middle cerebral artery occlusion (tMCAO). NSCs were transducted with circHIPK2 siRNA (si-circHIPK2-NSCs) or vehicle control (si-circCon-NSCs) and microinjected into lateral ventricle of brain at 7 d post-tMCAO. Magnetic resonance imaging (MRI) was used to detect brain damage, and functional deficits were evaluated with sensorimotor behavioural tests. The distribution of the transplanted NSCs was investigated by near-infrared fluorescence imaging (NIF) and immunofluorescence. The neural plasticity of si-circHIPK2-NSCs was verified by western blot and immunofluorescence in vivo and in vitro. FINDINGS: We investigated the role of circHIPK2 in NCS differentiation. In vitro, silencing of circHIPK2 facilitated NSCs directionally differentiated to neurons but had no effect on the differentiation to astrocytes. In vivo, microinjected NSCs could migrate to the ischaemic hemisphere after stroke induction. Si-circHIPK2-NSCs increased neuronal plasticity in the ischaemic brain, conferred long-lasting neuroprotection, and significantly reduced functional deficits. INTERPRETATIONS: Si-circHIPK2 regulates NSC differentiation, and microinjection of si-circHIPK2-NSCs exhibits a promising therapeutic strategy to neuroprotection and functional recovery after stroke. FUNDING: The National Key Research and Development Program of China; the International Cooperation and Exchange of the National Natural Science Foundation of China; the National Natural Science Foundation of China; the Jiangsu Innovation & Entrepreneurship Team Program.

16.
PLoS One ; 15(2): e0214041, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32084129

RESUMO

Soil microbial communities and enzyme activities together affect various ecosystem functions of soils. Fertilization, an important agricultural management practice, is known to modify soil microbial characteristics; however, inconsistent results have been reported. The aim of this research was to make a comparative study of the effects of different nitrogen (N) fertilizer rates and types (organic and inorganic) on soil physicochemical properties, enzyme activities and microbial attributes in a greenhouse vegetable production (GVP) system of Tianjin, China. Results showed that manure substitution of chemical fertilizer, especially at a higher substitution rate, improved soil physicochemical properties (higher soil organic C (SOC) and nutrient (available N and P) contents; lower bulk densities), promoted microbial growth (higher total phospholipid fatty acids and microbial biomass C contents) and activity (higher soil hydrolase activities). Manure application induced a higher fungi/bacteria ratio due to a lower response in bacterial than fungal growth. Also, manure application greatly increased bacterial stress indices, as well as microbial communities and functional diversity. The principal component analysis showed that the impact of manure on microbial communities and enzyme activities were more significant than those of chemical fertilizer. Furthermore, redundancy analysis indicated that SOC and total N strongly influenced the microbial composition, while SOC and ammonium-N strongly influenced the microbial activity. In conclusion, manure substitution of inorganic fertilizer, especially at a higher substitution rate, was more efficient for improving soil quality and biological functions.


Assuntos
Fertilizantes/efeitos adversos , Esterco/microbiologia , Microbiota/efeitos dos fármacos , Microbiologia do Solo , Verduras/crescimento & desenvolvimento , Apium/crescimento & desenvolvimento , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Fungos/efeitos dos fármacos , Fungos/crescimento & desenvolvimento , Lycopersicon esculentum/crescimento & desenvolvimento , Solo/química
17.
Nanoscale ; 12(9): 5521-5532, 2020 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-32091066

RESUMO

Iron based nanomedicine (IBNM) has been one powerful diagnostic tool as a magnetic resonance imaging (MRI) contrast agent (CA) in the clinic for years. Conventional IBNMs are generally employed as T2-MRI CAs, but most of them are constrained in clinical indication expansion by magnetic susceptibility artifacts. In comparison, extremely small iron oxide (ESIO) with a core size less than 5 nm has demonstrated the T1-MRI effect, which provides prospects for a Gd-based agent alternative. Nevertheless, currently developed ESIOs for T1-MRI CAs always require harsh conditions such as a high temperature and high boiling point reagent. Moreover, very few of the currently developed ESIOs meet the stringent pharmaceutical standard. Herein, on the basis of a crystal nuclear precipitation-dissolution equilibrium mechanism and outer/inner sphere T1-MRI theory, monodisperse ESIOs with an average size of 3.43 nm (polydispersity index of 0.104) are fabricated using a moderate cooling procedure with mild coprecipitation reaction conditions. The as-synthesized ESIOs display around 3-fold higher T1 MRI signal intensity than that of commercial Ferumoxytol (FMT), comparable to that of Gd-based CAs in vitro. Additionally, the T1-MRI performance of the ESIOs is pH dependent and delivers bright signal augmentation. Eventually, the internalization into mesenchymal stem cells of the ESIO is realized in the absence of a transferring agent. Considering the identical structure and composition of the ESIOs as compared to that of FMT, they could meet the pharmaceutical criteria, thus providing great potential as T1-MRI Cas, for instance as stem cell tracers.

18.
J Transl Med ; 18(1): 66, 2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-32046740

RESUMO

BACKGROUND: Translationally controlled tumor protein (TCTP) is linked to lung cancer. However, upon lung cancer carcinogens stimulation, there were no reports on the relationship between TCTP and lung cell carcinogenic epithelial-mesenchymal transition (EMT). This study was designed to investigate the molecular mechanism of regulation of TCTP expression and its role in lung carcinogens-induced EMT. METHODS: To study the role of TCTP in lung carcinogens [particulate matter 2.5 (PM2.5) or 4-methylnitrosamino-l-3-pyridyl-butanone (NNK)]-induced EMT, PM2.5/NNK-treated lung epithelial and non-small cell lung cancer (NSCLC) cells were tested. Cell derived xenografts, human lung cancer samples and online survival analysis were used to confirm the results. MassArray assay, Real-time PCR and Reporter assays were performed to elucidate the mechanism of regulation of TCTP expression. All statistical analyses were performed using GraphPad Prism version 6.0 or SPSS version 20.0. RESULTS: Translationally controlled tumor protein and vimentin expression were up-regulated in PM2.5/NNK-treated lung cells and orthotopic implantation tumors. TCTP expression was positively correlated with vimentin in human NSCLC samples. Patients with high expression of TCTP displayed reduced overall and disease-free survival. TCTP overexpression could increase vimentin expression and promote cell metastasis. Furthermore, PM2.5/NNK stimulation brought a synergistic effect on EMT in TCTP-transfected cells. TCTP knockdown blocked PM2.5/NNK carcinogenic effect. Mechanically, PM2.5/NNK-induced TCTP expression was regulated by one microRNA, namely miR-125a-3p, but not by methylation on TCTP gene promoter. The level of TCTP was regulated by its specific microRNA during the process of PM2.5/NNK stimulation, which in turn enhanced vimentin expression and played a permissive role in carcinogenic EMT. CONCLUSIONS: Our results provided new insights into the mechanisms of TCTP regulatory expression in lung carcinogens-induced EMT. TCTP and miR-125a-3p might act as potential prognostic biomarkers and therapeutic targets for NSCLC.

19.
Sci Rep ; 10(1): 2427, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-32051425

RESUMO

The prognosis of advanced stage cervical cancer is poorer due to cancer invasion and metastasis. Exploring new factors and signalling pathways associated with invasiveness and metastasis would help to identify new therapeutic targets for advanced cervical cancer. We searched the cancer microarray database, Oncomine, and found elevated calponin 3 (CNN3) mRNA expression in cervical cancer tissues. QRT-PCR verified the increased CNN3 expression in cervical cancer compared to para-cancer tissues. Proliferation, migration and invasion assays showed that overexpressed CNN3 promoted the viability and motility of cervical cancer cells, the opposite was observed in CNN3-knockdown cells. In addition, xenografted tumours, established from SiHa cells with CNN3 knockdown, displayed decreased growth and metastasis in vivo. Furthermore, RNA-sequencing showed that ribosomal protein lateral stalk subunit P1 (RPLP1) was a potential downstream gene. Gene function experiments revealed that RPLP1 had the same biological effects as CNN3 did. Rescue experiments demonstrated that the phenotypes inhibited by CNN3 silencing were partly or completely reversed by RPLP1 overexpression. In conclusion, we verified that CNN3 acts as an oncogene to promote the viability and motility of cervical cancer cells in vitro and accelerate the growth and metastasis of xenografted tumours in vivo, by affecting RPLP1 expression.

20.
Nature ; 579(7797): 152-157, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32076264

RESUMO

GPR52 is a class-A orphan G-protein-coupled receptor that is highly expressed in the brain and represents a promising therapeutic target for the treatment of Huntington's disease and several psychiatric disorders1,2. Pathological malfunction of GPR52 signalling occurs primarily through the heterotrimeric Gs protein2, but it is unclear how GPR52 and Gs couple for signal transduction and whether a native ligand or other activating input is required. Here we present the high-resolution structures of human GPR52 in three states: a ligand-free state, a Gs-coupled self-activation state and a potential allosteric ligand-bound state. Together, our structures reveal that extracellular loop 2 occupies the orthosteric binding pocket and operates as a built-in agonist, conferring an intrinsically high level of basal activity to GPR523. A fully active state is achieved when Gs is coupled to GPR52 in the absence of an external agonist. The receptor also features a side pocket for ligand binding. These insights into the structure and function of GPR52 could improve our understanding of other self-activated GPCRs, enable the identification of endogenous and tool ligands, and guide drug discovery efforts that target GPR52.


Assuntos
Receptores Acoplados a Proteínas-G/química , Receptores Acoplados a Proteínas-G/metabolismo , Regulação Alostérica , Sítio Alostérico , Motivos de Aminoácidos , Sequência de Aminoácidos , Apoproteínas/agonistas , Apoproteínas/química , Apoproteínas/metabolismo , Sítios de Ligação , Microscopia Crioeletrônica , Cristalografia por Raios X , Subunidades alfa Gs de Proteínas de Ligação ao GTP/química , Subunidades alfa Gs de Proteínas de Ligação ao GTP/metabolismo , Subunidades alfa Gs de Proteínas de Ligação ao GTP/ultraestrutura , Humanos , Ligantes , Modelos Moleculares , Receptores Acoplados a Proteínas-G/agonistas , Receptores Acoplados a Proteínas-G/ultraestrutura
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