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1.
Sci Rep ; 14(1): 12028, 2024 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-38797735

RESUMO

Obesity is a risk factor for pancreatic cancer development, partly due to the tissue environment of metabolic disorder-related inflammation. We aimed to detect a tissue environment marker triggered by obesity-related metabolic disorders related to pancreatic cancer progression. In murine experiments, Bl6/j mice fed a normal diet (ND) or a high-fat diet (HFD) were orthotopically injected with mPKC1, a murine-derived pancreatic cancer cell line. We used stocked sera from 140 pancreatic cancer patients for analysis and 14 colon polyp patients as a disease control. Compared with ND-fed mice, HFD-fed mice exhibited obesity, larger tumors, and worse prognoses. RNA sequencing of tumors identified tenascin C (TNC) as a candidate obesity-related serum tissue environment marker with elevated expression in tumors of HFD-fed mice. Serum TNC levels were greater in HFD-fed mice than in ND-fed mice. In pancreatic cancer patients, serum TNC levels were greater than those in controls. The TNC-high group had more metabolic disorders and greater CA19-9 levels than did the TNC-low group. There was no relationship between serum TNC levels and disease stage. Among 77 metastatic patients treated with chemotherapy, a high serum TNC concentration was an independent poor prognostic factor. Pancreatic cancer patients with high serum TNC levels experienced progression more rapidly.


Assuntos
Biomarcadores Tumorais , Dieta Hiperlipídica , Inflamação , Neoplasias Pancreáticas , Tenascina , Neoplasias Pancreáticas/sangue , Neoplasias Pancreáticas/patologia , Tenascina/sangue , Animais , Humanos , Prognóstico , Camundongos , Masculino , Inflamação/sangue , Dieta Hiperlipídica/efeitos adversos , Feminino , Pessoa de Meia-Idade , Biomarcadores Tumorais/sangue , Obesidade/sangue , Obesidade/complicações , Idoso , Linhagem Celular Tumoral , Doenças Metabólicas/sangue , Camundongos Endogâmicos C57BL
2.
Cancer Sci ; 115(3): 859-870, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38287498

RESUMO

There are approximately 250 million people chronically infected with hepatitis B virus (HBV) worldwide. Although HBV is often integrated into the host genome and promotes hepatocarcinogenesis, vulnerability of HBV integration in liver cancer cells has not been clarified. The aim of our study is to identify vulnerability factors for HBV-associated hepatocarcinoma. Loss-of-function screening was undertaken in HepG2 and HBV-integrated HepG2.2.15 cells expressing SpCas9 using a pooled genome-wide clustered regularly interspaced short palindromic repeats (CRISPR) library. Genes whose guide RNA (gRNA) abundance significantly decreased in HepG2.2.15 cells but not in HepG2 cells were extracted using the MAGeCK algorithm. We identified four genes (BCL2L1, VPS37A, INSIG2, and CFLAR) that showed significant reductions of gRNA abundance and thus potentially involved in the vulnerability of HBV-integrated cancer cells. Among them, siRNA-mediated mRNA inhibition or CRISPR-mediated genetic deletion of INSIG2 significantly impaired cell proliferation in HepG2.2.15 cells but not in HepG2 cells. Its inhibitory effect was alleviated by cotransfection of siRNAs targeting HBV. INSIG2 inhibition suppressed the pathways related to cell cycle and DNA replication, downregulated cyclin-dependent kinase 2 (CDK2) levels, and delayed the G1 -to-S transition in HepG2.2.15 cells. CDK2 inhibitor suppressed cell cycle progression in HepG2.2.15 cells and INSIG2 inhibition did not suppress cell proliferation in the presence of CDK2 inhibitor. In conclusion, INSIG2 inhibition induced cell cycle arrest in HBV-integrated hepatoma cells in a CDK2-dependent manner, and thus INSIG2 might be a vulnerability factor for HBV-associated liver cancer.


Assuntos
Carcinoma Hepatocelular , Hepatite B , Neoplasias Hepáticas , Humanos , Vírus da Hepatite B/genética , Vírus da Hepatite B/metabolismo , Carcinoma Hepatocelular/genética , RNA Guia de Sistemas CRISPR-Cas , Neoplasias Hepáticas/genética , Linhagem Celular , Células Hep G2 , RNA Interferente Pequeno/metabolismo , Replicação Viral/genética , Hepatite B/genética , DNA Viral/genética , Proteínas de Membrana/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo
3.
ACS Appl Mater Interfaces ; 15(30): 36076-36085, 2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37466273

RESUMO

Silicon has the potential to improve lithium-ion battery (LIB) performance substantially by replacing graphite as an anode. The sustainability of such a transformation, however, depends on the source of silicon and the nature of the manufacturing process. Today's silicon industry still overwhelmingly depends on the energy-intensive, high-temperature carbothermal reduction of silica─a process that adversely impacts the environment. Rather than use conventional thermoreduction alone to break Si-O bonds, we report the efficient conversion of SiO2 directly to Mg2Si by a microwave-induced Mg plasma within 2.5 min at merely 200 W under vacuum. The underlying mechanism is proposed, wherein electrons with enhanced kinetics function readily as the reductant while the "bombardment" from Mg cations and electrons promotes the fast nucleation of Mg2Si. The 3D nanoporous (NP) Si is then fabricated by a facile thermal dealloying step. The resulting hierarchical NP Si anodes deliver stable, extended cycling with excellent rate capability in Li-ion half-cells, with capacities several times greater than graphite. The microwave-induced metal plasma (MIMP) concept can be applied just as efficiently to the synthesis of Mg2Si from Si, and the chemistry should be extendable to the reduction of multiple metal(loid) oxides via their respective Mg alloys.

4.
Sci Rep ; 13(1): 5438, 2023 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-37012348

RESUMO

We report in this paper the muography of an archaeological site located in the highly populated "Sanità" district in the center of Naples, ten meters below the current street level. Several detectors capable of detecting muons - high energy charged particles produced by cosmic rays in the upper layers of atmosphere - were installed underground at the depth of 18 m, to measure the muon flux over several weeks. By measuring the differential flux with our detectors in a wide angular range, we have produced a radiographic image of the upper layers. Despite the architectural complexity of the site, we have clearly observed the known structures as well as a few unknown ones. One of the observed new structures is compatible with the existence of a hidden, currently inaccessible, burial chamber.

5.
Nat Commun ; 14(1): 1144, 2023 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-36864018

RESUMO

Khufu's Pyramid is one of the largest archaeological monument all over the world, which still holds many mysteries. In 2016 and 2017, the ScanPyramids team reported on several discoveries of previously unknown voids by cosmic-ray muon radiography that is a non-destructive technique ideal for the investigation of large-scale structures. Among these discoveries, a corridor-shaped structure has been observed behind the so-called Chevron zone on the North face, with a length of at least 5 meters. A dedicated study of this structure was thus necessary to better understand its function in relation with the enigmatic architectural role of this Chevron. Here we report on new measurements of excellent sensitivity obtained with nuclear emulsion films from Nagoya University and gaseous detectors from CEA, revealing a structure of about 9 m length with a transverse section of about 2.0 m by 2.0 m.

6.
Cancers (Basel) ; 15(2)2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36672412

RESUMO

We evaluated the value of secreted glycoprotein thrombospondin-2 (TSP-2) to predict hepatocellular carcinoma (HCC) occurrence in chronic hepatitis C (CHC) patients after Hepatitis C virus (HCV) elimination by direct-acting antiviral agents (DAAs). A total of 786 CHC patients without an HCC history who achieved a sustained virological response (SVR) with DAAs were randomly assigned 2:1, with 524 patients as the derivation cohort and 262 patients as the validation cohort. Serum TSP-2 levels at the end of treatment were measured by enzyme-linked immunosorbent assay (ELISA). In the derivation cohort, the cumulative HCC rate was significantly higher in the high TSP-2 group than in the low TSP-2 group. Multivariate Cox proportional hazards analysis revealed that TSP-2, α-fetoprotein (AFP), and the fibrosis-4 (FIB-4) index were independent HCC risk factors. The area under the receiver operating characteristic curve (AUROC) of the score calculated from these three factors (AFT score) for predicting HCC was 0.83, which was significantly higher than that of each factor alone (TSP-2: 0.70, AFP: 0.72, FIB-4: 0.69). The AFT score was used to stratify patients according to the risk of HCC occurrence in the validation cohort. Lastly, in patients with a FIB-4 index < 3.25, the serum TSP-2 levels could be used to identify those patients with a high risk of HCC occurrence. Serum TSP-2 levels are a predictive biomarker of HCC occurrence in CHC patients after HCV elimination by DAA treatment. The AFT score using TSP-2, AFP, and the FIB-4 index may identify those who require HCC surveillance.

7.
PLoS One ; 17(12): e0279416, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36542633

RESUMO

BACKGROUND: Patients with advanced fibrosis are at risk for developing hepatocellular carcinoma (HCC) even after hepatitis C virus (HCV) elimination. We previously reported that serum fucosylated haptoglobin (Fuc-Hp) levels increase as the disease progresses from chronic hepatitis to cirrhosis and then HCC. However, it remains unclear whether serum Fuc-Hp levels can stratify the risk of HCC occurrence after a sustained virological response (SVR) is achieved with direct-acting antivirals (DAAs) in patients with advanced liver fibrosis. METHODS: Among 3,550 patients with chronic hepatitis C treated with DAAs at Osaka University Hospital and related hospitals, the stored sera of 140 patients who were diagnosed with F3 or F4 by liver biopsy before DAA treatment, achieved SVR, and had no history of HCC were available at both baseline and the end of treatment (EOT). We measured the Fuc-Hp levels in these samples. RESULTS: The median serum levels of Fuc-Hp at EOT were significantly lower than those at baseline. During the 54.4-month follow-up period, 16 of 140 patients developed HCC. Multivariate Cox proportional hazards analysis revealed that high Fuc-Hp at EOT, high body mass index (BMI), and low albumin at EOT were independent risk factors for HCC occurrence. Patients with all three factors-high Fuc-Hp, high BMI, and low albumin-had a higher incidence of HCC than patients without these factors. CONCLUSIONS: High serum Fuc-Hp levels at EOT were an independent risk factor for HCC occurrence after SVR. Combined with BMI and albumin, Fuc-Hp can stratify the risk of HCC occurrence among those with advanced fibrosis.


Assuntos
Carcinoma Hepatocelular , Hepatite C Crônica , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patologia , Antivirais/uso terapêutico , Neoplasias Hepáticas/patologia , Hepacivirus , Haptoglobinas/uso terapêutico , Hepatite C Crônica/complicações , Hepatite C Crônica/tratamento farmacológico , Cirrose Hepática/diagnóstico , Resposta Viral Sustentada
8.
Cancer Sci ; 113(12): 4311-4326, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36074525

RESUMO

Cancer cachexia, a paraneoplastic syndrome characterized by ongoing skeletal muscle mass loss, is accompanied by adipose tissue loss and strongly affects chemotherapy endurance. Our aim was to detect a serum marker reflecting pancreatic cancer cachexia and predicting subsequent loss of muscle mass and adipose tissue, focusing on adipose tissue-secreted proteins. Murine-derived pancreatic cancer cells were orthotopically injected into the mouse pancreatic tail. After 3 weeks, RNA sequencing of perigonadal fat and orthotopic tumors was carried out. We analyzed stocked sera and clinical data of metastatic pancreatic cancer patients who received chemotherapy. Perigonadal fat weight/body weight decreased in mice with orthotopic tumors compared to those without tumors. By RNA sequencing and real-time PCR validation, pentraxin 3 (PTX3) was identified as a secreted protein-encoded gene whose expression was significantly higher in the perigonadal fat of mice with orthotopic tumors than in that of mice without orthotopic tumors and was least expressed in orthotopic tumors. Serum PTX3 levels correlated with PTX3 mRNA levels in perigonadal fat and were higher in mice with orthotopic tumors than in those without tumors. In 84 patients diagnosed with metastatic pancreatic cancer, patients with high serum PTX3 levels showed a greater visceral fat loss/month and skeletal muscle mass index (SMI) decrease/month than those with low serum PTX3 levels. High serum PTX3 was an independent risk factor for visceral fat loss, decreased SMI, and poor prognosis. High serum PTX3 in pancreatic cancer patients predicts visceral fat and muscle mass loss and major clinical outcomes of cancer cachexia.


Assuntos
Gordura Intra-Abdominal , Neoplasias Pancreáticas , Camundongos , Animais , Gordura Intra-Abdominal/metabolismo , Gordura Intra-Abdominal/patologia , Caquexia/etiologia , Neoplasias Pancreáticas/genética , Tecido Adiposo , Biomarcadores/metabolismo , Músculos/metabolismo , Músculo Esquelético/patologia , Neoplasias Pancreáticas
9.
Nat Commun ; 13(1): 5446, 2022 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-36114169

RESUMO

The increasing incidence of hepatitis C virus (HCV) infections underscores the need for an effective vaccine. Successful vaccines to other viruses generally depend on a long-lasting humoral response. However, data on the half-life of HCV-specific responses are lacking. Here we study archived sera and mononuclear cells that were prospectively collected up to 18 years after cure of chronic HCV infection to determine the role of HCV antigen in maintaining neutralizing antibody and B cell responses. We show that HCV-neutralizing activity decreases rapidly in potency and breadth after curative treatment. In contrast, HCV-specific memory B cells persist, and display a restored resting phenotype, normalized chemokine receptor expression and preserved ability to differentiate into antibody-secreting cells. The short half-life of HCV-neutralizing activity is consistent with a lack of long-lived plasma cells. The persistence of HCV-specific memory B cells and the reduced inflammation after cure provide an opportunity for vaccination to induce protective immunity against re-infection.


Assuntos
Hepatite C Crônica , Hepatite C , Células B de Memória , Anticorpos Neutralizantes , Hepacivirus/genética , Hepatite C Crônica/terapia , Humanos , Células B de Memória/metabolismo , Células B de Memória/virologia , Receptores de Quimiocinas , Vacinas contra Hepatite Viral
10.
J Chromatogr A ; 1678: 463364, 2022 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-35914409

RESUMO

This paper systematically investigated and reported for the first time the identification and quantification of co-eluting impurities as low as 0.05 area% by PDA with i-PDeA II deconvolution software in the LabSolutions Chromatographic Data System (CDS) using an integrated multivariate curve resolution-alternating least squares (MCR-ALS) algorithm with a bidirectional exponentially modified Gaussian (BEMG) model function. The algorithm was able to consistently identify 0.05% impurities when co-eluting with the main component (Rs ≥ 0.8) as well as when co-eluting with another impurity (Rs ≥ 0.5). In the case of two co-eluting impurities from 0.05% to 1% (Rs ≥ 0.5), the quantification error ranged from +10.6% to -16.7%. In the case of an impurity co-eluting with the main component (Rs ≥ 0.8), the quantification error was 4.4-8.9% for 1% impurity and 109-184% for 0.05% impurity. The precision was excellent for the range of 0.05-1.0% impurities with the RSD being 1.4-3.0% for 1% impurity and 4.0-8.7% for 0.05% impurity. The identification rate and quantitation accuracy were not affected by the spectral similarity of the molecules, as comparable results were obtained by analyzing two molecules with low similarity (4,4-difluorobenzophenone and valerophenone) and two molecules with high similarity (diazepam and oxazepam) based on simulated data. This peak resolution by MCR-ALS approach provides fast and robust identification and quantification of co-eluting impurities even when method development efforts do not provide complete separation of the target peaks, and could therefore find a wide range of applications in pharmaceutical and other types of analyses.


Assuntos
Algoritmos , Software , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida , Análise dos Mínimos Quadrados , Análise Multivariada , Preparações Farmacêuticas
12.
Sci Transl Med ; 13(587)2021 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-33790025

RESUMO

Pegylated interferon-α (PEG-IFN-α), where IFN-α is attached to polyethylene glycol (PEG), is an approved treatment for chronic hepatitis B virus (HBV) infection, a disease that causes liver-related morbidity and mortality in 257 million people worldwide. It is unknown why only a minority of patients respond to PEG-IFN-α. Using sequential blood samples and liver biopsies of patients with chronic HBV infection before, during, and after PEG-IFN-α treatment, we find that patients with early natural killer (NK) cell activation after PEG-IFN-α injection experienced greater liver inflammation, lysis of HBV-infected hepatocytes, and hepatitis B surface antigen (HBsAg) decline than those without. NK cell activation was associated with induction of interferon-stimulated genes and determined by PEG-IFN-α pharmacokinetics. Patients with delayed increases in PEG-IFN-α concentrations had greater amounts of PEG-specific immunoglobulin M (IgM) immune complexes in the blood and more PEG and IgM detected in the liver than patients with rapid increase in PEG-IFN-α concentration. This was associated with reduced NK cell activation. These results indicate that the immunomodulatory functions of PEG-IFN-α, particularly activation of NK cells, play a pivotal role in the response to treatment and further demonstrate that these functions are affected by PEG-IFN-α pharmacokinetics. Accelerated clearance of antibody-complexed pegylated drugs by Kupffer cells may be important beyond the field of HBV therapeutics. Thus, these findings may contribute to improving the efficacy of pegylated drugs that are now being developed for other chronic diseases and cancer.


Assuntos
Vírus da Hepatite B , Hepatite B Crônica , Antivirais/uso terapêutico , Hepatite B Crônica/tratamento farmacológico , Humanos , Células Matadoras Naturais , Células de Kupffer , Polietilenoglicóis , Proteínas Recombinantes/uso terapêutico , Resultado do Tratamento
13.
Phys Rev E ; 102(5-1): 053211, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33327100

RESUMO

Collisional radiative (CR) models based on ab initio atomic structure calculation have been utilized over 20 years to analyze many-electron atomic and ionic spectra. Although the population distribution of the excited states in plasmas and their emission spectra are computed using CR models, systematic and analytical understanding of the population kinetics is still lacking. In this work, we present a reduced model of the population dynamics in many-electron atomic ions, in which we approximate the dense energy structure of complex many-electron atoms by a continuum, a continuous CR model (CCRM). Using this simplification, we show an analytical population distribution of many-electron atoms in plasmas and its electron-density and temperature dependence. In particular, the CCRM shows that the population distribution of highly excited states of many-electron atoms in plasmas resembles a Boltzmann distribution but with an effective excitation temperature. We also show the existence of three typical electron-density regions and two electron-temperature regions where the parameter dependence of the excitation temperature is different. Analytical representations of the effective excitation temperature and the boundaries of these phases are also presented.

14.
Immunity ; 51(6): 975-977, 2019 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-31951542

RESUMO

Integrating transcriptomic, proteomic, and metabolomic data, Lercher et al. show in a mouse model of LCMV infection that type I interferon alters the expression and function of key enzymes of the urea cycle in hepatocytes. This results in altered systemic metabolism, attenuating antiviral T cell responses and ameliorating liver injury.


Assuntos
Antivirais , Interferon Tipo I , Animais , Fígado , Vírus da Coriomeningite Linfocítica , Camundongos , Proteômica , Linfócitos T , Ureia
15.
Hepatol Commun ; 2(10): 1247-1258, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30288478

RESUMO

Natural killer cells (NK cells) play an essential role in the immunological mechanism underlying chronic hepatitis C (CHC). Impairment of NK cell function facilitates persistent infection with hepatitis C virus (HCV) and hepatocellular carcinogenesis. However, the mechanism by which NK cell activity is suppressed in CHC is not completely understood. In this study, we focused on carcinoembryonic antigen-related cell-adhesion molecule 1 (CEACAM1). CEACAM1 is thought to suppress NK cell function. We examined the effect of CEACAM1 on NK cell function in CHC. We investigated the function of CEACAM1 in vitro using Huh7.5.1 cells and the HCV-Japanese fulminant hepatitis (JFH)-1 strain. We analyzed serum CEACAM1 level, NK cell function, and CEACAM1 messenger RNA (mRNA) level in human liver samples. Levels of CEACAM1 on the cell surface, CEACAM1 mRNA levels, and soluble CEACAM1 levels in supernatants were significantly higher in Huh7.5.1 cells infected with JFH-1 (Huh7.5.1/JFH-1 cells) than in Huh7.5.1 cells. Significantly higher NK cell cytotoxicity was observed toward K562 cells after coculture with CEACAM1 knockout Huh7.5.1/JFH-1 cells than after coculture with Huh7.5.1/JFH-1 cells. CEACAM1 expression was induced by the HCV E2 glycoprotein in HCV infection. Significantly higher serum CEACAM1 levels were detected in patients with CHC compared with healthy subjects and patients who achieved sustained virological responses. The expression of CD107a on NK cells from patients with CHC was negatively correlated with serum CEACAM1 levels. Significantly higher levels of CEACAM1 mRNA were detected in HCV-infected livers compared with uninfected livers. Conclusion: CEACAM1 expression was induced in hepatocytes following HCV infection and decreased NK cell cytotoxicity. These results demonstrate a possible role for CEACAM1 in the pathogenesis of CHC and hepatocellular carcinoma progression.

16.
Biochem Biophys Res Commun ; 503(3): 1457-1464, 2018 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-30033102

RESUMO

It is well known that immune-mediated virus elimination is necessary for the treatment of HBV infection. Reconstitution of human immune cells in liver chimeric mice is warranted to understand the immunopathogenesis of HBV infection. Here, we report a new immunologically humanized mouse model with a human immune system via reconstitution of immunodeficient NOG-Iaß/ß2 m double KO mice, which are NOG mice that are deficient in both MHC class I and II (DKO-NOG mice), with human HLA-A2-positive peripheral blood mononuclear cells (PBMCs). After injection of PBMCs, the xenogeneic graft-versus-host disease observed in PBMC-engrafted NOG mice was prevented in PBMC-engrafted DKO-NOG mice. Liver damage was reduced, and the survival time was prolonged in human PBMC-engrafted DKO-NOG mice compared to those in the NOG mice. The expression levels of PD-1 and Tim-3 on human T cells from PBMC-engrafted DKO-NOG mice were lower than those from NOG mice. By induction of HBV-specific T cell responses, such as vaccination with HBc-derived, peptide-pulsed DCs, hydrodynamic injection of HBV vector and intrasplenic injection of HepG2.2.15, the number of HBc-derived, peptide-specific CTLs increased in PBMC-engrafted DKO-NOG mice. Moreover, the recombinant HBV vaccine resulted in the production of hepatitis B surface antibody in 50% of the vaccinated mice. The induction of HBV-specific immune responses could be established in the immunologically humanized mice.


Assuntos
Vírus da Hepatite B/imunologia , Leucócitos Mononucleares/imunologia , Animais , Modelos Animais de Doenças , Células Hep G2 , Humanos , Camundongos , Camundongos Knockout , Camundongos SCID , Linfócitos T/imunologia
17.
Chem Commun (Camb) ; 54(25): 3178-3181, 2018 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-29528352

RESUMO

We report a battery made from a single material using Li1.5Cr0.5Ti1.5(PO4)3 as the anode, cathode and electrolyte. A high rate capability at room temperature and very low-temperature operation (233 K) were possible as a result of the superior ionic conductivity and low interfacial resistance obtained from the single-phase cell design.

18.
Nature ; 552(7685): 386-390, 2017 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-29160306

RESUMO

The Great Pyramid, or Khufu's Pyramid, was built on the Giza plateau in Egypt during the fourth dynasty by the pharaoh Khufu (Cheops), who reigned from 2509 bc to 2483 bc. Despite being one of the oldest and largest monuments on Earth, there is no consensus about how it was built. To understand its internal structure better, we imaged the pyramid using muons, which are by-products of cosmic rays that are only partially absorbed by stone. The resulting cosmic-ray muon radiography allows us to visualize the known and any unknown voids in the pyramid in a non-invasive way. Here we report the discovery of a large void (with a cross-section similar to that of the Grand Gallery and a minimum length of 30 metres) situated above the Grand Gallery. This constitutes the first major inner structure found in the Great Pyramid since the nineteenth century. The void, named ScanPyramids' Big Void, was first observed with nuclear emulsion films installed in the Queen's chamber, then confirmed with scintillator hodoscopes set up in the same chamber and finally re-confirmed with gas detectors outside the pyramid. This large void has therefore been detected with high confidence by three different muon detection technologies and three independent analyses. These results constitute a breakthrough for the understanding of the internal structure of Khufu's Pyramid. Although there is currently no information about the intended purpose of this void, these findings show how modern particle physics can shed new light on the world's archaeological heritage.

19.
PLoS Pathog ; 13(5): e1006374, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28494029

RESUMO

miR-122, a liver-specific microRNA, is one of the determinants for liver tropism of hepatitis C virus (HCV) infection. Although miR-122 is required for efficient propagation of HCV, we have previously shown that HCV replicates at a low rate in miR-122-deficient cells, suggesting that HCV-RNA is capable of propagating in an miR-122-independent manner. We herein investigated the roles of miR-122 in both the replication of HCV-RNA and the production of infectious particles by using miR-122-knockout Huh7 (Huh7-122KO) cells. A slight increase of intracellular HCV-RNA levels and infectious titers in the culture supernatants was observed in Huh7-122KO cells upon infection with HCV. Moreover, after serial passages of HCV in miR-122-knockout Huh7.5.1 cells, we obtained an adaptive mutant, HCV122KO, possessing G28A substitution in the 5'UTR of the HCV genotype 2a JFH1 genome, and this mutant may help to enhance replication complex formation, a possibility supported by polysome analysis. We also found the introduction of adaptive mutation around miR-122 binding site in the genotype 1b/2a chimeric virus, which originally had an adenine at the nucleotide position 29. HCV122KO exhibited efficient RNA replication in miR-122-knockout cells and non-hepatic cells without exogenous expression of miR-122. Competition assay revealed that the G28A mutant was dominant in the absence of miR-122, but its effects were equivalent to those of the wild type in the presence of miR-122, suggesting that the G28A mutation does not confer an advantage for propagation in miR-122-rich hepatocytes. These observations may explain the clinical finding that the positive rate of G28A mutation was higher in miR-122-deficient PBMCs than in the patient serum, which mainly included the hepatocyte-derived virus from HCV-genotype-2a patients. These results suggest that the emergence of HCV mutants that can propagate in non-hepatic cells in an miR-122-independent manner may participate in the induction of extrahepatic manifestations in chronic hepatitis C patients.


Assuntos
Hepacivirus/fisiologia , Hepatite C/virologia , MicroRNAs/genética , Replicação Viral , Regiões 5' não Traduzidas/genética , Linhagem Celular Tumoral , Hepacivirus/genética , Hepatócitos/virologia , Humanos , Fígado/metabolismo , Fígado/virologia , MicroRNAs/metabolismo , Mutação , Especificidade de Órgãos , RNA Viral/genética
20.
PLoS One ; 12(3): e0174103, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28328926

RESUMO

BACKGROUND AND AIM: Natural Killer (NK) cells are involved in the control of viral infection. However, the role of NK cells in chronic hepatitis B (CHB) remains unclear. This study investigated the frequencies and roles of NK cells in CHB, with a focus on activating receptor NKp46 and inhibitory receptor NKG2A. PATIENTS/METHOD: Peripheral blood lymphocytes were obtained from 71 CHB patients and 37 healthy subjects (HS). The expressions of NKp46 and NKG2A were analyzed using flow cytometry. The role of NKp46-ligand was assessed using an in vitro co-culture system. Cytotoxicity and IFN-γ production in NK cells were evaluated using RT-PCR and flow cytometry. RESULTS: CHB patients were classified into treatment-naïve patients with low HBV DNA titer (CHB-L; n = 28), high HBV DNA titer (CHB-H; n = 24) by the cut-off level of serum HBV DNA 4 log copies/ml, and patients receiving nucleos(t)ide analogue (CHB-NA; n = 19). The expressions of NKp46 and NKG2A were higher in CHB-H than in HS/CHB-L/CHB-NA. HepG2.2.15 had higher NKp46-ligand expression than HepG2. When NK cells from HS were co-cultured with HepG2.2.15, inhibition of the NKp46 and NKp46-ligand interaction by anti-NKp46 antibody significantly reduced cytolysis of HepG2.2.15 and IFN-γ production. However, those reductions were not observed in co-culture with HepG2. Additionally, NK cells that highly expressed NKp46 also highly expressed NKG2A (NKp46highNKG2Ahigh subset). The frequencies of NKp46highNKG2Ahigh subset in CHB-H were higher than those in HS/CHB-L/CHB-NA. Among treatment-naïve CHB patients, the frequencies of NKp46highNKG2Ahigh subset were positively correlated with serum ALT (P<0.01, r = 0.45) and HBV DNA (P<0.01, r = 0.59) levels. The expressions of Fas-L, STAT1, TRAIL and CD107a were higher and IFN-γ expression was lower in the NKp46highNKG2Ahigh subset than in the other subsets. CONCLUSION: The NKp46 and NKp46-ligand interaction contributes to NK cell activation. A novel NK cell subset, the NKp46highNKG2Ahigh subset, may be associated with liver injury and HBV replication.


Assuntos
Hepatite B Crônica/metabolismo , Subfamília C de Receptores Semelhantes a Lectina de Células NK/metabolismo , Receptor 1 Desencadeador da Citotoxicidade Natural/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Linhagem Celular Tumoral , Técnicas de Cocultura/métodos , DNA Viral/genética , Feminino , Células Hep G2 , Vírus da Hepatite B/genética , Humanos , Interferon gama/metabolismo , Células Matadoras Naturais/metabolismo , Ativação Linfocitária/fisiologia , Masculino , Pessoa de Meia-Idade , Replicação Viral/genética
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