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1.
Artigo em Inglês | MEDLINE | ID: mdl-32414918

RESUMO

Water wires are critical for the functioning of many membrane proteins, as in channels that conduct water, protons, and other ions. Here, in liquid crystalline lipid bilayers under symmetric environmental conditions, the selective hydrogen bonding interactions between eight waters comprising a water wire and a subset of 26 carbonyl oxygens lining the antiparallel dimeric gramicidin A channel are characterized by 17O NMR spectroscopy at 35.2 T (or 1,500 MHz for 1H) and computational studies. While backbone 15N spectra clearly indicate structural symmetry between the two subunits, single site 17O labels of the pore-lining carbonyls report two resonances, implying a break in dimer symmetry caused by the selective interactions with the water wire. The 17O shifts document selective water hydrogen bonding with carbonyl oxygens that are stable on the millisecond timescale. Such interactions are supported by density functional theory calculations on snapshots taken from molecular dynamics simulations. Water hydrogen bonding in the pore is restricted to just three simultaneous interactions, unlike bulk water environs. The stability of the water wire orientation and its electric dipole leads to opposite charge-dipole interactions for K+ ions bound at the two ends of the pore, thereby providing a simple explanation for an ∼20-fold difference in K+ affinity between two binding sites that are ∼24 Šapart. The 17O NMR spectroscopy reported here represents a breakthrough in high field NMR technology that will have applications throughout molecular biophysics, because of the acute sensitivity of the 17O nucleus to its chemical environment.

2.
J Mol Biol ; 2020 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-32470558

RESUMO

We present solid-state NMR measurements of ß-strand secondary structure and inter-strand organization within a 150 kDa oligomeric aggregate of the 42-residue variant of the Alzheimer's amyloid-ß peptide (Aß(1-42)). We build upon our previous report of a ß-strand spanned by residues 30-42, which arranges into an antiparallel ß-sheet. New results presented here indicate that there is a second ß-strand formed by residues 11-24. Contrary to expectations, NMR data indicate that this second ß-strand is organized into a parallel ß-sheet despite the co-existence of an antiparallel ß-sheet in the same structure. In addition, the in-register parallel ß-sheet commonly observed for amyloid fibril structure does not apply to residues 11-24 in the 150 kDa oligomer. Rather, we present evidence for an inter-strand registry shift of 3 residues that likely alternates in direction between adjacent molecules along the ß-sheet. We corroborated this unexpected scheme for ß-strand organization using multiple 2-dimensional NMR and 13C-13C dipolar recoupling experiments. Our findings indicate a previously unknown assembly pathway and inspire a suggestion as to why this aggregate does not grow to larger sizes.

3.
Nature ; 581(7807): 215-220, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32225176

RESUMO

A new and highly pathogenic coronavirus (severe acute respiratory syndrome coronavirus-2, SARS-CoV-2) caused an outbreak in Wuhan city, Hubei province, China, starting from December 2019 that quickly spread nationwide and to other countries around the world1-3. Here, to better understand the initial step of infection at an atomic level, we determined the crystal structure of the receptor-binding domain (RBD) of the spike protein of SARS-CoV-2 bound to the cell receptor ACE2. The overall ACE2-binding mode of the SARS-CoV-2 RBD is nearly identical to that of the SARS-CoV RBD, which also uses ACE2 as the cell receptor4. Structural analysis identified residues in the SARS-CoV-2 RBD that are essential for ACE2 binding, the majority of which either are highly conserved or share similar side chain properties with those in the SARS-CoV RBD. Such similarity in structure and sequence strongly indicate convergent evolution between the SARS-CoV-2 and SARS-CoV RBDs for improved binding to ACE2, although SARS-CoV-2 does not cluster within SARS and SARS-related coronaviruses1-3,5. The epitopes of two SARS-CoV antibodies that target the RBD are also analysed for binding to the SARS-CoV-2 RBD, providing insights into the future identification of cross-reactive antibodies.


Assuntos
Betacoronavirus/química , Peptidil Dipeptidase A/química , Peptidil Dipeptidase A/metabolismo , Receptores Virais/química , Receptores Virais/metabolismo , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/metabolismo , Sequência de Aminoácidos , Anticorpos Neutralizantes/imunologia , Betacoronavirus/metabolismo , Sítios de Ligação , Sequência Conservada , Cristalografia por Raios X , Epitopos/química , Epitopos/imunologia , Evolução Molecular , Humanos , Ligação de Hidrogênio , Modelos Moleculares , Ligação Proteica , Domínios Proteicos , Vírus da SARS/química , Sais/química , Alinhamento de Sequência , Água/análise , Água/química
4.
Cell ; 181(4): 894-904.e9, 2020 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-32275855

RESUMO

The recent emergence of a novel coronavirus (SARS-CoV-2) in China has caused significant public health concerns. Recently, ACE2 was reported as an entry receptor for SARS-CoV-2. In this study, we present the crystal structure of the C-terminal domain of SARS-CoV-2 (SARS-CoV-2-CTD) spike (S) protein in complex with human ACE2 (hACE2), which reveals a hACE2-binding mode similar overall to that observed for SARS-CoV. However, atomic details at the binding interface demonstrate that key residue substitutions in SARS-CoV-2-CTD slightly strengthen the interaction and lead to higher affinity for receptor binding than SARS-RBD. Additionally, a panel of murine monoclonal antibodies (mAbs) and polyclonal antibodies (pAbs) against SARS-CoV-S1/receptor-binding domain (RBD) were unable to interact with the SARS-CoV-2 S protein, indicating notable differences in antigenicity between SARS-CoV and SARS-CoV-2. These findings shed light on the viral pathogenesis and provide important structural information regarding development of therapeutic countermeasures against the emerging virus.


Assuntos
Betacoronavirus/química , Peptidil Dipeptidase A/química , Glicoproteína da Espícula de Coronavírus/química , Internalização do Vírus , Sequência de Aminoácidos , Betacoronavirus/fisiologia , Epitopos , Humanos , Modelos Moleculares , Peptidil Dipeptidase A/metabolismo , Filogenia , Domínios Proteicos , Vírus da SARS/química , Vírus da SARS/fisiologia , Alinhamento de Sequência , Glicoproteína da Espícula de Coronavírus/metabolismo
5.
J Ethnopharmacol ; 259: 112852, 2020 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-32278759

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Hypervascularity has been considered as one of the major features of many solid tumors. Green tea is one of the commonly drink resources in China, and its active component, Epigallocatechin gallate (EGCG), exhibits antiangiogenic activities in various experimental tumor models. However, EGCG has many shortages, e.g., relatively unstable, low lipid solubility, poor bioavailability, and short duration of action. AIM OF THE STUDY: To overcome the shortages of EGCG for antiangiogenic antitumor usage, our study developed a novel EGCG derivate, Y6(5,3',4',3″,4″,5″-6-0-ethyl-EGCG). The underlying mechanism was also elucidated. MATERIAL AND METHODS: we evaluated the effects of EGCG, Y6 on HCC and angiogenesis in vivo and in vitro. Moreover, to understand their antitumor mechanisms, key factors within angiogenesis-related signaling pathways (MAPK/ERK1/2, PI3K/AKT, HIF-1 VEGF) were analyzed by using western blot, immunohistochemistry (IHC), quantitative real-time quantitative PCR (RT-PCR). HepG2 xenograft model and the chorioallantoic membrane (CAM) were used to investigate the effects of Y6 and EGCG on tumors and anti-angiogenesis in vivo. Micro-vessel density (MVD) was analyzed by IHC of CD34 staining. IHC, qRT-PCR and Western blot were used to detect the expression of HIF-1α and VEGF protein in tumor tissues. The protein levels of MAPK/ERK1/2, PI3K/AKT, HIF-1α, and VEGF in tumor tissues were detected by western blot. RESULTS: Our results demonstrated that both EGCG and Y6 displayed antiangiogenetic and antitumor effects against HCC cells in vitro and in vivo. We found that rather than equal amount of EGCG, Y6 displayed better abilities in inhibiting the growth of HCC tumor cells, as well as inhibiting the growth of neovascularization in the chick embryos and HepG2 xenograft tumors bearing-mice, based on the data obtained from MTT assay, immunohistochemistry (IHC), chick chorioallantoic membrane (CAM) assays. In the comparison of equivalent dose of EGCG, qRT-PCR data showed that Y6 induced more significant decrease of the mRNA levels of HIF-1α and VEGF in supernatant-treated SMMC-7721 cells under hypoxic condition, as well as in the in xenograft tumor tissues; whereas Y6 also significantly reduced the protein levels of MAPK/ERK1/2, PI3K/AKT, HIF-1α, and VEGF to a greater extent than EGCG, determined by western blotting assay. CONCLUSIONS: our work suggests that the new EGCG derivate Y6 could significantly inhibit tumor growth and angiogenesis which is possibly involved with the signaling intervention of MAPK/ERK1/2 and PI3K/AKT/HIF-1α/VEGF pathways, and is supposed to be a potential therapeutic reagent for anti-angiogenesis treatment of solid tumors.

6.
J Am Chem Soc ; 142(19): 8848-8861, 2020 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-32326697

RESUMO

Membraneless organelles, comprising dozens to hundreds of macromolecular components, form heterogeneous phases in space and evolve over time in material properties. Here, using four macromolecules, we demonstrate a range of phase behaviors associated with membraneless organelles and uncover the underlying physicochemical rules. The macromolecules are SH35 (S) and PRM5 (P), two pentameric, oppositely charged protein constructs; heparin (H), an anionic polymer; and lysozyme (L), a cationic single-domain protein. The S:P, S:L, and P:H binaries form droplets, but the H:L binary forms network-like precipitates, therefore setting up a tug of war between different condensate phases within the S:P:H:L quaternary. The H:L exception can partly be attributed to the compactness of L, as supported by ThT binding data. Increasing amounts of P alone or both S and P, but not S alone, can dissolve H:L precipitates into droplets. These differential effects can be explained by the order of the strengths of pairwise attraction: H:L > P:H > S:P > S:L, deduced from the shapes of ternary phase boundaries. When S and P are at subdissolution concentrations, S:P:H:L precipitates change over time to become droplet-like in appearance, although not completely fluidic according to fluorescence recovery after photobleaching. In fact, confocal microscopy reveals separated S:L-rich and P:H-rich foci inside the droplet-like condensates. Therefore, complex phase behaviors of membraneless organelles, including rescue of aberrant phase transitions, demixing of condensates, and time evolution of material properties, can all be reconstituted and understood via a minimal macromolecular system.

7.
J Infect Chemother ; 26(6): 636-639, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32173284

RESUMO

The spread of carbapenemase-producing Enterobacteriaceae (CPE) is a major threat to public health. In the present study, we compared the difference between meropenem and imipenem disk for detecting carbapenemase-producing gram-negative bacilli using simplified carbapenem inactivation method (sCIM). 106 Enterobacteriaceae, including 74 CPE, 17 Pseudomonas aeruginosa including 10 carbapenemase-producing isolates and 36 Acinetobacter baumannii including 20 carbapenem-resistant isolates preserved in our laboratory were tested. Based on sCIM method, the test bacteria were tested with both meropenem and imipenem disk, respectively. In Enterobacteriaceae, the usage of both meropenem and imipenem disk showed high concordance (99.1%). Meropenem disk cannot identify positive isolates among the 10 P. aeruginosa and 20 A. baumannii isolates due to low carbapenem hydrolytic ability of the carbapenemase produced by these strains. Thus, meropenem disk was found to be similar to imipenem disk, presenting high specificity and sensitivity in the detection of carbapenemase in Enterobacteriaceae, but it cannot be used for the detection of carbapenemase in P. aeruginosa and A. baumannii.

8.
Stem Cell Res Ther ; 11(1): 110, 2020 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-32143712

RESUMO

BACKGROUND: Although dental pulp stem cells (DPSCs) isolated from periodontally compromised teeth (P-DPSCs) have been demonstrated to retain pluripotency and regenerative potential, their use as therapeutics remains largely unexplored. In this study, we investigated the proangiogenic effects of extracellular vesicles (EVs) secreted by P-DPSCs using in vitro and in vivo testing models. METHODS: Patient-matched DPSCs derived from periodontally healthy teeth (H-DPSCs) were used as the control for P-DPSCs. Conditioned media (CMs) derived from H-DPSCs and P-DPSCs (H-CM and P-CM), CMs derived from both cell types pretreated with the EV secretion blocker GW4869 (H-GW and P-GW), and EVs secreted by H-DPSCs and P-DPSCs (H-EVs and P-EVs) were prepared to test their proangiogenic effects on endothelial cells (ECs). Cell proliferation, migration, and tube formation were assessed using the Cell Counting Kit-8 (CCK-8), transwell/scratch wound healing, and Matrigel assays, respectively. Specifically, quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) and western blot analysis were used to examine the expression levels of angiogenesis-related genes/proteins in ECs in response to EV-based incubation. Finally, a full-thickness skin defect model was applied to test the effects of EVs on wound healing and new vessel formation. RESULTS: Both H-CM and P-CM promoted EC angiogenesis, but the proangiogenic effects were compromised when ECs were incubated in H-GW and P-GW, wherein the EV secretion was blocked by pretreatment with GW4869. In EV-based incubations, although both H-EVs and P-EVs were found to enhance the angiogenesis-related activities of ECs, P-EVs exerted a more robust potential to stimulate EC proliferation, migration, and tube formation. In addition, P-EVs led to higher expression levels of angiogenesis-related genes/proteins in ECs than H-EVs. Similarly, both P-EVs and H-EVs were found to accelerate wound healing and promote vascularization across skin defects in mice, but wounds treated with P-EVs resulted in a quicker healing outcome and enhanced new vessel formation. CONCLUSIONS: The findings of the present study provide additional evidence that P-DPSCs derived from periodontally diseased teeth represent a potential source of cells for research and therapeutic use. Particularly, the proangiogenic effects of P-EVs suggest that P-DPSCs may be used to promote new vessel formation in cellular therapy and regenerative medicine.

9.
Parasite ; 27: 12, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32129760

RESUMO

Enterocytozoon bieneusi is a zoonotic fungal pathogen with a high degree of host diversity that can parasitize many animals, including humans. Pigs may play an important role in the epidemiology of E. bieneusi as reservoir hosts. Nevertheless, the genotypes of E. bieneusi in pigs in China remain poorly understood. The aim of this study was to determine the prevalence of E. bieneusi infection amongst pigs raised on farms from four cities of Hainan Province, using nested polymerase chain reaction (PCR) of the partial small subunit of the ribosomal RNA gene, and to identify genotypes of E. bieneusi isolates based on sequence analysis of the ribosomal internal transcribed spacer (ITS) region. Among 188 stool samples, E. bieneusi was detected in 46.8% (88/188). Eight genotypes including four known (EbpA, CS-4, MJ14, and CHG19) and four novel (HNP-I - HNP-IV) genotypes were identified. Using phylogenetic analysis, genotypes EbpA, CS4, CHG19, HNP-III, and HNP-IV were clustered into zoonotic Group 1, while the remaining three genotypes (MJ14, HNP-I, and HNP-II) clustered into Group 10. The high prevalence of zoonotic genotypes of E. bieneusi among pigs suggests that pig farming is a potential source of human infection. Additionally, this is the first identification of genotypes in Group 10 in pigs indicating unique epidemic features of E. bieneusi in pigs in Hainan Province, the southernmost part of China.

10.
BMC Vet Res ; 16(1): 84, 2020 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-32151253

RESUMO

BACKGROUND: Cryptosporidium and Enterocytozoon bieneusi are two important pathogens with zoonotic potential that cause enteric infections in a wide range of hosts, including humans. Both are transmitted from animals to humans by direct contact or through contaminated equipment. Bears are frequently found in Chinese zoos as ornamental animals as well as farmed as commercial animals, and are therefore in close contact with zoo- or farm-keepers, but the prevalence and zoonotic potential of Cryptosporidium and E. bieneusi in bears is poorly understood. In this study, we aimed to provide data on the occurrence and genetic diversity of Cryptosporidium and E. bieneusi in Asiatic black bears from Heilongjiang and Fujian, China. From May 2015 to December 2017, 218 fresh fecal specimens were collected from captive Asiatic black bears in Heilongjiang (n = 36) and Fujian (n = 182), China. Cryptosporidium and E. bieneusi were examined by PCR amplification of the partial small subunit of ribosomal DNA (SSU rDNA) and the internal transcribed spacer (ITS) region of rDNA, respectively. C. andersoni-positive isolates were subtyped through PCR analysis of the four minisatellite/microsatellite (MS1, MS2, MS3 and MS16) loci. RESULTS: The overall prevalence of Cryptosporidium and E. bieneusi were 2.4% (4/218) and 6.4% (14/218), respectively, with 2.8% (1/36) and 22.2% (8/36) in the Heilongjiang Province, and 1.6% (3/182) and 3.3% (6/182) in the Fujian Province. Sequence analysis confirmed the presence of Cryptosporidium species: C. andersoni (n = 3) and a genotype termed Cryptosporidium rat genotype IV (n = 1). All three identified C. andersoni belonged to the MLST subtype A4, A4, A4, A1. Two known E. bieneusi genotypes D (n = 4) and SC02 (n = 10) were identified, both of which belong to zoonotic Group 1. CONCLUSIONS: This is the first report of C. andersoni and Cryptosporidium rat genotype IV in bears. The discovery of the zoonotic potential of E. bieneusi genotype D in bears highlights its significant zoonotic potential and potential threat to human health.

11.
Infect Dis Poverty ; 9(1): 29, 2020 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-32183901

RESUMO

BACKGROUND: The coronavirus disease (COVID-19) has been identified as the cause of an outbreak of respiratory illness in Wuhan, Hubei Province, China beginning in December 2019. As of 31 January 2020, this epidemic had spread to 19 countries with 11 791 confirmed cases, including 213 deaths. The World Health Organization has declared it a Public Health Emergency of International Concern. METHODS: A scoping review was conducted following the methodological framework suggested by Arksey and O'Malley. In this scoping review, 65 research articles published before 31 January 2020 were analyzed and discussed to better understand the epidemiology, causes, clinical diagnosis, prevention and control of this virus. The research domains, dates of publication, journal language, authors' affiliations, and methodological characteristics were included in the analysis. All the findings and statements in this review regarding the outbreak are based on published information as listed in the references. RESULTS: Most of the publications were written using the English language (89.2%). The largest proportion of published articles were related to causes (38.5%) and a majority (67.7%) were published by Chinese scholars. Research articles initially focused on causes, but over time there was an increase of the articles related to prevention and control. Studies thus far have shown that the virus' origination is in connection to a seafood market in Wuhan, but specific animal associations have not been confirmed. Reported symptoms include fever, cough, fatigue, pneumonia, headache, diarrhea, hemoptysis, and dyspnea. Preventive measures such as masks, hand hygiene practices, avoidance of public contact, case detection, contact tracing, and quarantines have been discussed as ways to reduce transmission. To date, no specific antiviral treatment has proven effective; hence, infected people primarily rely on symptomatic treatment and supportive care. CONCLUSIONS: There has been a rapid surge in research in response to the outbreak of COVID-19. During this early period, published research primarily explored the epidemiology, causes, clinical manifestation and diagnosis, as well as prevention and control of the novel coronavirus. Although these studies are relevant to control the current public emergency, more high-quality research is needed to provide valid and reliable ways to manage this kind of public health emergency in both the short- and long-term.


Assuntos
Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/virologia , Surtos de Doenças/prevenção & controle , Controle de Infecções , Pneumonia Viral , Betacoronavirus , China/epidemiologia , Técnicas de Laboratório Clínico , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/prevenção & controle , Tosse/etiologia , Dispneia/etiologia , Fadiga/etiologia , Febre/etiologia , Cefaleia/etiologia , Humanos , Pneumonia Viral/diagnóstico , Pneumonia Viral/epidemiologia , Pneumonia Viral/prevenção & controle , Pneumonia Viral/transmissão
12.
PLoS Pathog ; 16(3): e1008394, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32176738

RESUMO

Using bacteriophage-derived endolysins as an alternative strategy for fighting drug-resistant bacteria has recently been garnering renewed interest. However, their application is still hindered by their narrow spectra of activity. In our previous work, we demonstrated that the endolysin LysIME-EF1 possesses efficient bactericidal activity against multiple strains of Enterococcus faecalis (E. faecalis). Herein, we observed an 8 kDa fragment and hypothesized that it contributes to LysIME-EF1 lytic activity. To examine our hypothesis, we determined the structure of LysIME-EF1 at 1.75 Å resolution. LysIME-EF1 exhibits a unique architecture in which one full-length LysIME-EF1 forms a tetramer with three additional C-terminal cell-wall binding domains (CBDs) that correspond to the abovementioned 8 kDa fragment. Furthermore, we identified an internal ribosomal binding site (RBS) and alternative start codon within LysIME-EF1 gene, which are demonstrated to be responsible for the translation of the truncated CBD. To elucidate the molecular mechanism for the lytic activity of LysIME-EF1, we combined mutagenesis, lytic activity assays and in vivo animal infection experiments. The results confirmed that the additional LysIME-EF1 CBDs are important for LysIME-EF1 architecture and its lytic activity. To our knowledge, this is the first determined structure of multimeric endolysin encoded by a single gene in E. faecalis phages. As such, it may provide valuable insights into designing potent endolysins against the opportunistic pathogen E. faecalis.

13.
Brain Cogn ; 140: 105526, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32007788

RESUMO

OBJECTIVE: Pregnancy causes many changes in our body and some of them may affect our ability of learning and memory. We examined the cerebral cortical volume of brain during pregnancy and measured changes in the brain electrical activity and cerebral blood flow. METHOD: 35 women (20 normal full-term primigravida and 15 non-pregnant women) received the Electroencephalography (EEG) and Transcranial Doppler ultrasonography (TCD). 8 non-pregnant women and 9 primigravida after vaginal delivery underwent brain magnetic resonance imaging (MRI) voluntarily within 24 h. RESULTS: Compared with the non-pregnant, changes were shown by EEG through electrodes of T5, Pz, Cz, T6, F3 and F8. The results displayed increased activity in the central parietal area of pregnant women, while that in the temporoparietal junction decreased. The result of TCD revealed that pulsation index (PI) values of left and right internal and external carotid arteries were asymmetrical, but they all decreased in pregnancy. Atrophy of cortical volume had been found in many brain functional areas of pregnant women. The percentage of atrophy varied between 6.76% and 13.17%. CONCLUSION: Atrophy of cerebral cortex, changes in cerebral blood flow and neuron electrophysiology may be the physiological basis of the emotional, cognitive changes in pregnant women.

14.
Nat Commun ; 11(1): 739, 2020 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-32029730

RESUMO

Clear cell renal cell carcinoma (ccRCC) is a heterogeneous disease with features that vary by ethnicity. A systematic characterization of the genomic landscape of Chinese ccRCC is lacking, and features of ccRCC associated with tumor thrombus (ccRCC-TT) remain poorly understood. Here, we applied whole-exome sequencing on 110 normal-tumor pairs and 42 normal-tumor-thrombus triples, and transcriptome sequencing on 61 tumor-normal pairs and 30 primary-thrombus pairs from 152 Chinese patients with ccRCC. Our analysis reveals that a mutational signature associated with aristolochic acid (AA) exposure is widespread in Chinese ccRCC. Tumors from patients with ccRCC-TT show a higher mutational burden and genomic instability; in addition, mutations in BAP1 and SETD2 are highly enriched in patients with ccRCC-TT. Moreover, patients with/without TT show distinct molecular characteristics. We reported the integrative genomic sequencing of Chinese ccRCC and identified the features associated with tumor thrombus, which may facilitate ccRCC diagnosis, prognosis and treatment.


Assuntos
Carcinoma de Células Renais/genética , Neoplasias Renais/genética , Trombose/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Ácidos Aristolóquicos/toxicidade , Grupo com Ancestrais do Continente Asiático/genética , Carcinoma de Células Renais/complicações , Carcinoma de Células Renais/etiologia , China , Estudos de Coortes , Feminino , Perfilação da Expressão Gênica , Estudos de Associação Genética , Instabilidade Genômica , Humanos , Neoplasias Renais/complicações , Neoplasias Renais/etiologia , Masculino , Pessoa de Meia-Idade , Mutação , Prognóstico , Trombose/complicações , Trombose/etiologia , Sequenciamento Completo do Exoma
15.
Gen Physiol Biophys ; 39(1): 27-36, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32039822

RESUMO

The G protein-coupled estrogen receptor (GPER) was proved to be a new type of estrogen receptor (ER). It is unknown that whether estrogen can regulate the secretion of gonadotrophin releasing hormone (GnRH) in GT1-7 cells through the mechanism with the involvement of GPER. The GnRH, estradiol (17ß-estradiol, E2) and GPER in peripheral blood of precocious puberty children were detected by ELISA and RT-qPCR assays. After E2 treatment, the levels of GPER and GnRH in GT1-7 cells were detected. Following G1 treatment, cell proliferation was examined using a CCK-8 assay. The levels of GnRH, KISS1, GPR54, nNOS, c-FOS in GT1-7 cells were assessed following GT1-7 cells were induced by E2 combined with G1 or G15. GnRH, E2 and GPER were significantly increased in precocious puberty children. After E2 treatment, GT1-7 cells expressed more GnRH and GPER was markedly elevated and reached a peak at 8 h. The KISS1, GPR54 and nNOS in GT1-7 cells were significantly increased with G1 induction, but were significantly decreased with G15 induction compared with E2 induction alone. Collectively, GPER cannot promote the release of GnRH via affecting the proliferation of GT1-7 cells, but it may regulate GnRH through KISS1/GPR54 pathway, which provides novel ideas for precocious puberty children treatment.


Assuntos
Puberdade Precoce , Animais , Linhagem Celular , Estradiol , Estrogênios , Hormônio Liberador de Gonadotropina , Camundongos , Receptores Estrogênicos , Receptores Acoplados a Proteínas-G
16.
J Clin Lab Anal ; : e23216, 2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31967356

RESUMO

BACKGROUND: Clinically, D-dimer (DD) levels are mainly used to exclude diseases such as deep venous thrombosis (DVT). In clinical testing, DD assays can be subjected to interference that may cause false results, which directly affect the clinical diagnosis. Our hypothesis was that the 95% confidence intervals (CIs) of the fibrin degradation product (FDP)/DD and fibrinogen (Fib)/DD ratios were used to identify these false results and corrected via multiple dilutions. METHODS: In total, 16 776 samples were divided into three groups according to the DD levels detected by Sysmex CS5100 and CA7000: Group A, DD ≥ 2.0 µg/mL fibrinogen equivalent unit (FEU); group B, 0.5 < DD < 2.0 µg/mL FEU; and group C, DD ≤ 0.5 µg/mL FEU. The 95% CIs of the FDP/DD and Fib/DD ratios were calculated. Six abnormal DD results were found according to the 95% CIs. For verification, we performed multiple dilutions, compared the results with those of other instruments, and tested the addition of heterophilic blocking reagent (HBR). RESULTS: The median and 95% CI of the FDP/DD ratio were 3.76 and 2.25-8.15 in group A, 5.63 and 2.86-10.58 in group B, 10.23 and 0.91-47.71 in groups C, respectively. For the Fib/DD ratio, the 95% CIs was 0.02-2.21 in group A, 0.68-8.15 in group B, and 3.82-55.27 in groups C. Six abnormal results were identified after multiple dilutions, by comparison with other detection systems, and after HBR addition. CONCLUSIONS: The FDP/DD ratio is more reliable for identifying false results. If the FDP/DD ratio falls outside the 95% CI, it should be verified by different methods.

17.
Drug Metab Dispos ; 2020 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-31900255

RESUMO

Curcumin, a major polyphenol present in turmeric, is predominantly converted to curcumin-O-glucuronide (COG) in enterocytes and hepatocytes via glucuronidation. COG is a principal metabolite of curcumin in plasma and faeces. It appears that the efflux transport of the glucuronide conjugates of many compounds is mediated largely by MRP3 (multidrug resistance-associated protein 3, the gene product of the Abcc3). However, it is currently unknown whether this was the case with COG. In this study, Mrp3 knock-out (KO) and wild-type (WT) mice were used to evaluate the pharmacokinetics profiles of COG, the liver-to-plasma ratio of COG, and the COG-to-curcumin ratio in plasma, respectively. The ATP-dependent uptake of COG into recombinant human MRP3 inside-out membrane vesicles was measured for further identification, with estradiol-17ß-D-glucuronide used in parallel as the positive control. Results showed that plasma COG concentrations were extremely low in KO mice compared to WT mice, that the liver-to-plasma ratios of COG were 8-fold greater in KO mice than in WT mice, and that the ATP-dependent uptake of COG at 1 or 10 µM was 5.0- and 3.1-fold greater in the presence of ATP than in the presence of AMP, respectively. We conclude that Mrp3 is identified to be the main efflux transporter responsible for the transport of COG from hepatocytes into the blood. SIGNIFICANCE STATEMENT: This study was designed to elucidate the involvement of Mrp3 (multidrug resistance-associated protein 3) in the efflux transport of curcumin-O-glucuronide from hepatocytes into the blood using Mrp3 knock-out mice and to further corroborate mouse-derived findings using recombinant human MRP3 inside-out membrane vesicles. In this study, we identified that curcumin-O-glucuronide, a major metabolite of curcumin present in plasma and faeces, is a typical substrate of Mrp3 in mice and in humans. These new observations suggest that herb-drug interactions would occur in patients who concomitantly receive curcumin and either an MRP3 substrate/inhibitor or a drug that is glucuronidated by UGTs dominantly. In view of the widespread use of curcumin globally, such herb-drug interactions are of clinical importance.

18.
J Pharm Biomed Anal ; 179: 112955, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-31866139

RESUMO

Vicagrel is a promising novel antiplatelet drug. However, the quantification of vicagrel in plasma is currently unavailable since it is liable to be hydrolyzed in plasma by esterases. In this study, an optimized strategy was developed and validated to stabilize vicagrel, 2-oxo-clopidogrel (thiolactone metabolite), and H4 (active thiol metabolite) before quantification of the analytes, such as addition of citric acid (for plasma acidification) and NaF (a non-specific esterase inhibitor) to inhibit esterase activity, immediate addition of a thiol-alkylating reagent MPB into blood samples to derivatize H4 for the formation of stable H4 derivative (i.e., MP-H4), use of the anticoagulant K2EDTA to minimize the conversion of 2-oxo-clopidogrel to H-endo, and keeping the analytes at 4 °C or on wet ice to minimize degradation of the analytes when processed and analyzed. The stability was measured as percent of each analyte remained in plasma samples after their storage for 4 h at 4 °C or in blood samples after 1 h at 4 °C. The results indicated that stability of vicagrel was increased significantly in stabilized plasma or blood samples compared with non-stabilized controls for rats and humans, respectively, and that the stability of 2-oxo-clopidogrel was increased to a certain extent. In contrast, MP-H4 formed was stable in plasma immediately after thorough mixture of MPB with blood. We conclude that the above strategy is useful for improving the stability of vicagrel, 2-oxo-clopidogrel, and H4 in rat or human plasma, and that vicagrel and its two major metabolites can be quantified accurately and simultaneously.

20.
Psychol Health Med ; 25(5): 639-651, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31878790

RESUMO

The purposes of the current study were to explore the applicability of the Health Action Process Approach (HAPA) model for interpreting changes in physical exercise behavior and to examine the key determinants of changes in physical exercise. The participants were 639 rural middle school students in Sichuan province, China, who did not perform physical exercise. Three surveys and two interventions were completed in the same participants within 1.5 years. The HAPA model elements and physical exercise were estimated by a self-reported questionnaire. The results showed that 158 students (24.7%) formed a habit of physical exercise. The structural equation model for the pre-intention stage and behavior stage showed acceptable goodness of fit. Outcome expectancies (ß=0.136, P=0.014) and action self-efficacy (ß=0.314, P=0.001) directly predicted intention of physical exercise, the latter directly predicted physical exerciseplanning (ß=0.537, P<0.001), andplanning subsequently predicted physical exercise (ß=0.324, P<0.001). Maintenance self-efficacy indirectly predicted physical exercise through planning (95%CI: 0.014, 0.053). The findings suggested that the HAPA model was a very useful tool for predicting changes in physical exercise behavior, as this model explains the process of changing physical exercise habits and reveals the weak link in such behavioral changes among Chinese rural adolescents.

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