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1.
PLoS Pathog ; 20(2): e1011954, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38300891

RESUMO

Epstein-Barr virus (EBV) is a ubiquitous human lymphotropic herpesvirus that is causally associated with several malignancies. In addition to latent factors, lytic replication contributes to cancer development. In this study, we examined whether the lytic gene BNRF1, which is conserved among gamma-herpesviruses, has an important role in lymphomagenesis. We found that lymphoblastoid cell lines (LCLs) established by BNRF1-knockout EBV exhibited remarkably lower pathogenicity in a mice xenograft model than LCLs produced by wild-type EBV (LCLs-WT). RNA-seq analyses revealed that BNRF1 elicited the expression of interferon-inducible protein 27 (IFI27), which promotes cell proliferation. IFI27 knockdown in LCLs-WT resulted in excessive production of reactive oxygen species, leading to cell death and significantly decreased their pathogenicity in vivo. We also confirmed that IFI27 was upregulated during primary infection in B-cells. Our findings revealed that BNRF1 promoted robust proliferation of the B-cells that were transformed by EBV latent infection via IFI27 upregulation both in vitro and in vivo.


Assuntos
Infecções por Vírus Epstein-Barr , Herpesviridae , Humanos , Animais , Camundongos , Herpesvirus Humano 4 , Interferons/metabolismo , Regulação para Cima , Herpesviridae/metabolismo , Latência Viral , Proteínas de Membrana/metabolismo
2.
Biochem Biophys Res Commun ; 694: 149397, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38157582

RESUMO

The first small interfering RNA (siRNA) therapeutic received approval for hereditary transthyretin (ATTRv) amyloidosis, and the patients' lifespan extension by specific inhibition of hepatic synthesis of transthyretin (TTR) is expected. However, ocular amyloidosis in these patients has been a crucial issue. This study aims to evaluate the efficacy and safety of intravitreal TTR siRNA conjugate injection into rabbit eyes. Rabbit (r) TTR siRNA is a screened TTR siRNA conjugate from 53 candidates. The intraocular pressure (IOP) immediately after injection was high despite the 65.9 % decrease of aqueous humor TTR protein levels in the rTTR siRNA group compared with those in the Control siRNA group 2 weeks after the 50 µL siRNA injection. The IOP spike was milder after the 30 µL siRNA injection, and aqueous humor TTR levels decreased by ∼50 % in the rTTR siRNA group, which is consistent with the mRNA levels in the retina. The parameters of dark-adapted, light-adapted, and light-adapted 30 Hz electroretinogram and the thickness of each retinal layer in histological analysis demonstrated no significant differences between the groups. In conclusion, we developed TTR siRNA conjugates for rabbit eyes, and the results indicate that intravitreal TTR siRNA conjugate injection could be a therapeutic option for ocular amyloidosis caused by ATTRv amyloidosis.


Assuntos
Neuropatias Amiloides Familiares , Pré-Albumina , Animais , Humanos , Coelhos , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/uso terapêutico , Pré-Albumina/genética , Pré-Albumina/metabolismo , Injeções Intravítreas , Neuropatias Amiloides Familiares/terapia , Neuropatias Amiloides Familiares/tratamento farmacológico
3.
J Virol ; 97(6): e0043723, 2023 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-37195206

RESUMO

Enveloped viruses undergo a complex multistep process of assembly, maturation, and release into the extracellular space utilizing host secretory machinery. Several studies of the herpesvirus subfamily have shown that secretory vesicles derived from the trans-Golgi network (TGN) or endosomes transport virions into the extracellular space. However, the regulatory mechanism underlying the release of Epstein-Barr virus, a human oncovirus, remains unclear. We demonstrate that disruption of BBLF1, a tegument component, suppressed viral release and resulted in the accumulation of viral particles on the inner side of the vesicular membrane. Organelle separation revealed the accumulation of infectious viruses in fractions containing vesicles derived from the TGN and late endosomes. Deficiency of an acidic amino acid cluster in BBLF1 reduced viral secretion. Moreover, truncational deletion of the C-terminal region of BBLF1 increased infectious virus production. These findings suggest that BBLF1 regulates the viral release pathway and reveal a new aspect of tegument protein function. IMPORTANCE Several viruses have been linked to the development of cancer in humans. Epstein-Barr virus (EBV), the first identified human oncovirus, causes a wide range of cancers. Accumulating literature has demonstrated the role of viral reactivation in tumorigenesis. Elucidating the functions of viral lytic genes induced by reactivation, and the mechanisms of lytic infection, is essential to understanding pathogenesis. Progeny viral particles synthesized during lytic infection are released outside the cell after the assembly, maturation, and release steps, leading to further infection. Through functional analysis using BBLF1-knockout viruses, we demonstrated that BBLF1 promotes viral release. The acidic amino acid cluster in BBLF1 was also important for viral release. Conversely, mutants lacking the C terminus exhibited more efficient virus production, suggesting that BBLF1 is involved in the fine-tuning of progeny release during the EBV life cycle.


Assuntos
Herpesvirus Humano 4 , Vesículas Secretórias , Proteínas Virais , Liberação de Vírus , Replicação Viral , Humanos , Infecções por Vírus Epstein-Barr/virologia , Herpesvirus Humano 4/fisiologia , Vesículas Secretórias/metabolismo , Vesículas Secretórias/virologia , Vírion/fisiologia , Replicação Viral/fisiologia , Células HEK293 , Proteínas Virais/metabolismo , Liberação de Vírus/genética
4.
Circ J ; 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38897975

RESUMO

BACKGROUND: Abnormal coronary microcirculation is linked to poor patient prognosis, so the aim of the present study was to assess the prognostic relevance of basal microvascular resistance (b-IMR) in patients without functional coronary stenosis.Methods and Results: Analyses of 226 patients who underwent intracoronary physiological assessment of the left anterior descending artery included primary endpoints of all-cause death and heart failure, as well as secondary endpoints of cardiovascular death and atherosclerotic vascular events. During a median follow-up of 2 years, there were 12 (5.3%) primary and 21 (9.3 %) secondary endpoints. The optimal b-IMR cutoff for the primary endpoints was 47.1 U. Kaplan-Meier curve analysis demonstrated worse event-free survival of the primary endpoints in patients with a b-IMR below the cutoff (χ2=21.178, P<0.001). b-IMR was not significantly associated with the secondary endpoints (P=0.35). A low coronary flow reserve (CFR; <2.5) had prognostic value for both endpoints (primary endpoints: χ2=11.401, P=0.001; secondary endpoints: (χ2=6.015; P=0.014), and high hyperemic microvascular resistance (≥25) was associated only with the secondary endpoints (χ2=4.420; P=0.036). Incorporating b-IMR into a clinical model that included CFR improved the Net Reclassification Index and Integrated Discrimination Improvement for predicting the primary endpoints (P<0.001 and P=0.034, respectively). CONCLUSIONS: b-IMR may be a specific marker of the risk of death and heart failure in patients without functional coronary stenosis.

5.
J Am Chem Soc ; 145(47): 25894-25902, 2023 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-37972241

RESUMO

Taxol (1) is a clinically used antineoplastic diterpenoid. The tetracyclic ring system comprises a 6/8/6-membered carbocycle (ABC-ring) and a fused oxetane ring (D-ring) embedded with a bridgehead double bond and decorated with multiple oxygen functionalities. Here, we report a convergent total synthesis of this exceedingly complex natural product. The C-ring fragment was designed to possess a bromocyclohexenone and an extra tetrahydrofuran ring to control the reactivity and selectivity, as well as to minimize functional group manipulations en route to 1. The α-alkoxyacyl telluride of the A-ring served as a radical precursor, and intermolecular radical coupling with the C-ring realized the installation of the C2- and C3-stereocenters and reductive removal of the bromide. After the C8-quaternary stereocenter was constructed by exploiting the three-dimensional shape of the intermediate, the C11-vinyl triflate of A-ring and the C8-methyl ketone of C-ring were utilized for Pd(0)-catalyzed cyclization of the central eight-membered B-ring with the bridgehead olefin. Adjustment of the oxidation level and attachment of the oxetane D-ring completed the total synthesis of 1 (28 steps, as the longest linear sequence). The fragment design principle and implementation of the powerful radical coupling reaction described in the present synthesis provide valuable information for planning and executing syntheses of diverse densely oxygenated terpenoids.


Assuntos
Paclitaxel , Paládio , Paclitaxel/química , Ciclização , Éteres Cíclicos , Estereoisomerismo
6.
J Virol ; 96(14): e0051822, 2022 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-35862711

RESUMO

Protein-protein interactions (PPIs) are crucial for various biological processes. Epstein-Barr virus (EBV) proteins typically form complexes, regulating the replication and persistence of the viral genome in human cells. However, the role of EBV protein complexes under physiological conditions remains unclear. In this study, we performed comprehensive analyses of EBV PPIs in living cells using the NanoBiT system. We identified 195 PPIs, many of which have not previously been reported. Computational analyses of these PPIs revealed that BLRF2, which is only found in gammaherpesviruses, is a central protein in the structural network of EBV tegument proteins. To characterize the role of BLRF2, we generated two BLRF2 knockout EBV clones using CRISPR/Cas9. BLRF2 knockout significantly decreased the production of infectious virus particles, which was partially restored by exogenous BLRF2 expression. In addition, self-association of BLRF2 protein was found, and mutation of the residues crucial for the self-association affected stability of the protein. Our data imply that BLRF2 is a tegument network hub that plays important roles in progeny virion maturation. IMPORTANCE EBV remains a significant public health challenge, causing infectious mononucleosis and several cancer types. Therefore, the better understanding of the molecular mechanisms underlying EBV replication is of high clinical importance. As protein-protein interactions (PPIs) are major regulators of virus-associated pathogenesis, comprehensive analyses of PPIs are essential. Previous studies on PPIs in EBV or other herpesviruses have predominantly employed the yeast two-hybrid (Y2H) system, immunoprecipitation, and pulldown assays. Herein, using a novel luminescence-based method, we identified 195 PPIs, most of which have not previously been reported. Computational and functional analyses using knockout viruses revealed that BLRF2 plays a central role in the EBV life cycle, which makes it a valuable target for drug development.


Assuntos
Infecções por Vírus Epstein-Barr , Herpesvirus Humano 4 , Mapas de Interação de Proteínas , Proteínas Virais , Infecções por Vírus Epstein-Barr/virologia , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/fisiologia , Humanos , Proteínas Virais/genética , Replicação Viral
7.
Shokuhin Eiseigaku Zasshi ; 64(6): 240-245, 2023.
Artigo em Japonês | MEDLINE | ID: mdl-38171896

RESUMO

In general, nitrite in food is extracted under slightly alkaline conditions, deproteinized, and analyzed by a colorimetric method using color development by diazotization. However, depending on the sample, the sample solution may become cloudy and difficult to filter by the deproteinization treatment of the analytical method. Recently, an improved analytical method that solves these problems has been reported. Therefore, a validation study was performed on the improved analytical method was performed. The concentrations of sodium nitrite added to cod roe, fish sausage, and ham, which were not labeled with sodium nitrite, were set at the upper limits of the standards for use. We set the target values of 70-120% for trueness, less than 15% for intralaboratory reproducibility, and less than intralaboratory reproducibility for repeatability. As a result, the target values were met for the three samples verified: 88-92% for trueness, 2.0-3.0% for repeatability, and 3.2-4.3% for intralaboratory reproducibility. In addition, an interlaboratory study was conducted by eight institutes on the improved analytical method for nitrite. At each institution, sodium nitrite was added to the same three samples as in the validation study, at concentrations equivalent to twice the lower limit of quantification and the upper limit of the standards for use and analyzed in triplicate. The estimated trueness from the obtained analyses ranged from 82 to 95%, the repeatability ranged from 2.3 to 5.8%, and the inter-room reproducibility ranged from 3.5 to 11%. Thus, the improved analytical method could be useful for determining nitrite in foods.


Assuntos
Produtos da Carne , Nitrito de Sódio , Animais , Reprodutibilidade dos Testes , Produtos da Carne/análise , Colorimetria/métodos
8.
Cell Commun Signal ; 20(1): 95, 2022 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-35729616

RESUMO

BACKGROUND: Viruses must adapt to the environment of their host cells to establish infection and persist. Diverse mammalian cells, including virus-infected cells, release extracellular vesicles such as exosomes containing proteins and miRNAs, and use these vesicles to mediate intercellular communication. However, the roles of exosomes in viral infection remain unclear. RESULTS: We screened viral proteins to identify those responsible for the exosome-mediated enhancement of Epstein-Barr virus (EBV) infection. We identified BGLF2 protein encapsulated in exosomes, which were released by EBV-infected cells. BGLF2 protein is a tegument protein that exists in the space between the envelope and nucleocapsid, and it is released into the cytoplasm shortly after infection. BGLF2 protein-containing exosomes enhanced viral gene expression and repressed innate immunity, thereby supporting the EBV infection. CONCLUSIONS: The EBV tegument protein BGLF2 is encapsulated in exosomes and released by infected cells to facilitate the establishment of EBV infection. These findings suggest that tegument proteins support viral infection not only between the envelope and nucleocapsid, as well as in extraviral particles such as exosomes. Video abstract.


Assuntos
Infecções por Vírus Epstein-Barr , Exossomos , Animais , Infecções por Vírus Epstein-Barr/genética , Infecções por Vírus Epstein-Barr/metabolismo , Exossomos/metabolismo , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/metabolismo , Mamíferos/metabolismo , Proteínas Virais de Fusão , Proteínas Virais
9.
Cancer Sci ; 112(12): 5088-5099, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34609775

RESUMO

Epstein-Barr virus-associated lymphoproliferative disease (EBV-LPD) is frequently fatal. Innate immunity plays a key role in protecting against pathogens and cancers. The stimulator of interferon genes (STING) is regarded as a key adaptor protein allowing DNA sensors recognizing exogenous cytosolic DNA to activate the type I interferon signaling cascade. In terms of EBV tumorigenicity, the role of STING remains elusive. Here we showed that treatment with the STING inhibitor, C-176, suppressed EBV-induced transformation in peripheral blood mononuclear cells. In an EBV-LPD mouse model, C-176 treatment also inhibited tumor formation and prolonged survival. Treatment with B cells alone did not affect EBV transformation, but suppression of EBV-induced transformation was observed in the presence of T cells. Even without direct B cell-T cell contact in a transwell system, the inhibitor reduced the transformation activity, indicating that intercellular communication by humoral factors was critical to prevent EBV-induced transformation. These findings suggest that inhibition of STING signaling pathway with C-176 could be a new therapeutic target of EBV-LPD.


Assuntos
Antineoplásicos/administração & dosagem , Transformação Celular Viral/efeitos dos fármacos , Infecções por Vírus Epstein-Barr/tratamento farmacológico , Linfoma de Células B/prevenção & controle , Proteínas de Membrana/antagonistas & inibidores , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Infecções por Vírus Epstein-Barr/imunologia , Células HEK293 , Herpesvirus Humano 4 , Humanos , Células Jurkat , Linfoma de Células B/imunologia , Linfoma de Células B/virologia , Camundongos , Análise de Sobrevida , Linfócitos T/efeitos dos fármacos , Linfócitos T/metabolismo , Resultado do Tratamento , Ensaios Antitumorais Modelo de Xenoenxerto
10.
J Synchrotron Radiat ; 28(Pt 6): 1758-1768, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34738929

RESUMO

A new correction algorithm for closed orbit distortion based on an adaptive feedforward control (AFC) has been developed. At SPring-8, two helicity-switching twin-helical undulators (THUs) had been implemented with conventional feedforward corrections. However, the validity of these corrections turned out to be expiring due to unforeseen variation in the error magnetic fields with time. The developed AFC system has been applied to the THUs dynamically updating the feedforward table without stopping the helicity switching amid user experiments. The error sources in the two THUs are successfully resolved and corrected even while the two THUs are switching simultaneously with the same repetition period. The actual operation of the new AFC system enables us to keep the orbit variations suppressed with an accuracy at the sub-micrometre level in a transparent way for light source users.

11.
Exp Eye Res ; 210: 108708, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34332990

RESUMO

Elevated intraocular pressure (IOP) is a significant risk factor for vision loss due to glaucoma, which is a major cause of blindness worldwide. Glaucoma filtration surgery (GFS) is an important method to reduce IOP by guidance of aqueous humor into a newly built filtration bleb in the conjunctiva; management of the wound healing mechanism is essential for the success of GFS. Here, we investigated the roles of interleukin (IL)-6 family members during the wound healing process after GFS. At the surgical site, the expression levels of genes encoding IL-6, oncostatin M (OSM), their receptors, and collagen I were elevated at 3 h after GFS, whereas the levels of genes encoding transforming growth factor (TGF)-ß, α-smooth muscle actin (SMA), type IV collagen, and fibronectin were elevated at 3 days after GFS. IL-6 trans-signaling and OSM signaling suppressed TGF-ß-induced expression of α-SMA and collagen IV, as well as activation of the non-canonical TGF-ß pathway, suggesting that IL-6 and OSM may aid in controlling the phase transition from inflammation to proliferation and remodeling. The suppressive effects of OSM were accompanied by STAT3 activation, such that STAT1 function was complementary to STAT3. Taken together, these observations indicated that IL-6 family members constitute early response genes after GFS, which can suppress TGF-ß-induced expression of late response genes at the surgical site after GFS.


Assuntos
Fator Neurotrófico Ciliar/metabolismo , Túnica Conjuntiva/patologia , Interleucina-6/metabolismo , Fator Inibidor de Leucemia/metabolismo , Oncostatina M/metabolismo , Cicatrização/fisiologia , Actinas/metabolismo , Animais , Western Blotting , Colágeno Tipo IV/metabolismo , Túnica Conjuntiva/metabolismo , Feminino , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibrose , Glaucoma/cirurgia , Humanos , Coelhos , Reação em Cadeia da Polimerase em Tempo Real , Fator de Transcrição STAT1/metabolismo , Fator de Transcrição STAT3/metabolismo , Trabeculectomia , Fator de Crescimento Transformador beta/farmacologia
12.
Rev Med Virol ; 30(2): e2095, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31845495

RESUMO

Epstein-Barr virus (EBV) is a causative agent of infectious mononucleosis and several malignancies involving lymphocytes and epithelial cells. We recently reported genomic analyses of chronic active EBV infection (CAEBV), a proliferative disorder of T and/or NK cells, as well as other lymphoid malignancies. We found that T and/or NK cells undergoing clonal expansion in CAEBV patients gain somatic driver mutations as the disorder progresses. Investigation of the viral genome revealed viral genomes harboring intragenic deletions in the BamHI-rightward transcripts (BART) region and in essential lytic genes. Interestingly, we observed that these deletions resulted in leaky expression of viral lytic genes. This increased expression of viral lytic genes is reminiscent of the "pre-latent abortive lytic" state, in which a substantial number of lytic genes are produced for weeks in the absence of progeny production, which contributes to cell survival upon de novo infection. It has been known that EBV can choose either latent or lytic state, but this dualistic concept may need to be reconsidered, as our data suggest the presence of the third, intermediate state; leaky expression of lytic genes that does not lead to completion of the full lytic amplification cycle. Leaky expression of lytic genes likely contributes to the formation and maintenance of several types of EBV-associated tumors. We also presented significant circumstantial evidence suggesting that EBV infects lymphoid progenitor cells in CAEBV before differentiation into T and NK cells. Taken together, our new data shed light on oncogenesis of CAEBV and other EBV-associated malignancies.


Assuntos
Transformação Celular Viral , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/virologia , Herpesvirus Humano 4/fisiologia , Suscetibilidade a Doenças , Infecções por Vírus Epstein-Barr/imunologia , Regulação Viral da Expressão Gênica , Genoma Viral , Interações Hospedeiro-Patógeno/genética , Humanos , Deleção de Sequência , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Subpopulações de Linfócitos T/patologia , Subpopulações de Linfócitos T/virologia
13.
Cancer Sci ; 111(1): 209-218, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31724785

RESUMO

Analysis of anticancer immunity aids in assessing the prognosis of patients with breast cancer. From 250 operated breast cancers, we focused on serum levels of C-C motif chemokine ligand 5 (CCL5), which is involved in cancer immune reactions. Serum levels of CCL5 were measured using a cytometric bead-based immunoassay kit and CCL5 expression in cancer cells was determined using immunohistochemical staining. In addition, mRNA in cancer and stromal cells was analyzed by microdissection and comparison with the public dataset. Disease-free survival (DFS) of patients with high CCL5 levels (cut-off, 13.87 ng/mL; n = 192) was significantly better than those with low CCL5 levels (n = 58; hazard ratio, 0.20; 95% confidence interval, 0.10-0.39; P < .0001). An improved overall survival was observed in patients with high CCL5 levels compared to those with low CCL5 levels (P = .024). On the contrary, high immunohistochemical expression of CCL5 in cancer cells was significantly associated with decreased DFS. As serum CCL5 levels did not correlate with CCL5 expression in cancer cells and the relative expression of mRNA CCL5 was elevated in stromal cells in relation to cancer cells, serum CCL5 might be derived not from cancer cells, but from stromal cells. Expression of CCL5 in serum, but not in cancer cells, might contribute to improved patient prognosis mediating through not only immune reaction, but through other mechanisms. Determination of circulating CCL5 levels could be useful for predicting patient prognosis.


Assuntos
Neoplasias da Mama/sangue , Neoplasias da Mama/mortalidade , Quimiocina CCL5/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/sangue , Neoplasias da Mama/patologia , Intervalo Livre de Doença , Feminino , Humanos , Pessoa de Meia-Idade , Prognóstico , RNA Mensageiro/metabolismo
14.
Cancer Sci ; 111(1): 279-287, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31743514

RESUMO

Epstein-Barr virus (EBV) is a well-established tumor virus that has been implicated in a wide range of immunodeficiency-associated lymphoproliferative disorders (LPDs). Although rituximab, a CD20 mAb, has proven effective against EBV-associated LPDs, prolonged use of this drug could lead to resistance due to the selective expansion of CD20- cells. We have previously shown that cyclin-dependent kinase (CDK) inhibitors are able to specifically suppress the expression of viral late genes, particularly those encoding structural proteins; however, the therapeutic effect of CDK inhibitors against EBV-associated LPDs is not clear. In this study, we examined whether CDK inhibitors confer a therapeutic effect against LPDs in vivo. Treatment with alsterpaullone, an inhibitor of the CDK2 complex, resulted in a survival benefit and suppressed tumor invasion in a mouse model of LPDs. Inhibition of CDK efficiently induced G1 cell cycle arrest and apoptosis in EBV-positive B cells. These results suggest that alsterpaullone suppresses cell cycle progression, resulting in the antitumor effect observed in vivo.


Assuntos
Antineoplásicos/farmacologia , Benzazepinas/farmacologia , Herpesvirus Humano 4/patogenicidade , Indóis/farmacologia , Transtornos Linfoproliferativos/tratamento farmacológico , Transtornos Linfoproliferativos/virologia , Inibidores de Proteínas Quinases/farmacologia , Animais , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular , Quinase 2 Dependente de Ciclina/antagonistas & inibidores , Infecções por Vírus Epstein-Barr/tratamento farmacológico , Infecções por Vírus Epstein-Barr/genética , Infecções por Vírus Epstein-Barr/virologia , Fase G1/efeitos dos fármacos , Células HEK293 , Humanos , Transtornos Linfoproliferativos/genética , Camundongos , Camundongos Endogâmicos NOD
15.
J Virol ; 93(8)2019 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-30700607

RESUMO

Temporally controlled gene expression is necessary for the propagation of herpesviruses. To achieve this, herpesviruses encode several transcriptional regulators. In Epstein-Barr virus, BcRF1 associates with five viral proteins (BDLF4, BGLF3, BFRF2, BVLF1, and BDLF3.5) to form the viral late (L) gene regulatory complex, which is called the viral preinitiation complex (vPIC), on TATT-containing promoters. However, regulation of the vPIC has been largely unexplored. In this study, we performed two screens using a kinase inhibitor library and identified a series of cyclin-dependent kinase (CDK) inhibitors that downregulated the expression of L genes without any impact on viral DNA replication through destabilization of the BDLF4 protein. Knockdown of CDK2 by short hairpin RNA (shRNA) and proteasome inhibitor treatment showed that phosphorylation of the BDLF4 protein prevented ubiquitin-mediated degradation. Moreover, we demonstrated that cyclin A- and E-associated CDK2 complexes phosphorylated BDLF4 in vitro, and we identified several serine/threonine phosphorylation sites in BDLF4. Phosphoinactive and phosphomimic mutants revealed that phosphorylation at threonine 91 plays a role in stabilizing BDLF4. Therefore, our findings indicate that S-like-phase CDKs mediate the regulation of L gene expression through stabilization of the BDLF4 protein, which makes the temporal L gene expression system more robust.IMPORTANCE Late (L) genes represent more than one-third of the herpesvirus genome, suggesting that many of these genes are indispensable for the life cycle of the virus. With the exception of BCRF1, BDLF2, and BDLF3, Epstein-Barr virus L genes are transcribed by viral regulators, which are known as the viral preinitiation complex (vPIC) and the host RNA polymerase II complex. Because the vPIC is conserved in beta- and gammaherpesviruses, studying the control of viral L gene expression by the vPIC contributes to the development of drugs that specifically inhibit these processes in beta- and gammaherpesvirus infections/diseases. In this study, we demonstrated that CDK inhibitors induced destabilization of the vPIC component BDLF4, leading to a reduction in L gene expression and subsequent progeny production. Our findings suggest that CDK inhibitors may be a therapeutic option against beta- and gammaherpesviruses in combination with existing inhibitors of herpesvirus lytic replication, such as ganciclovir.


Assuntos
Quinase 2 Dependente de Ciclina/metabolismo , Regulação Viral da Expressão Gênica , Herpesvirus Humano 4/metabolismo , Proteólise , Transcrição Gênica , Proteínas Virais/metabolismo , Quinase 2 Dependente de Ciclina/antagonistas & inibidores , Quinase 2 Dependente de Ciclina/genética , Técnicas de Silenciamento de Genes , Células HEK293 , Herpesvirus Humano 4/genética , Humanos , Fosforilação/efeitos dos fármacos , Fosforilação/genética , Inibidores de Proteassoma/farmacologia , Estabilidade Proteica , Ubiquitina/genética , Ubiquitina/metabolismo , Proteínas Virais/genética
16.
World J Surg Oncol ; 18(1): 125, 2020 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-32527279

RESUMO

BACKGROUND: Gastrointestinal stromal tumors (GISTs) generally form well-defined mass lesions. However, some cases of the flatly distributed and muscularis propria-replacing GISTs have been reported so far. We experienced an additional case of planar-type GIST of the sigmoid colon accompanied by a diverticulum with perforation. CASE PRESENTATION: A 68-year-old Japanese male with sudden onset of abdominal pain was clinically diagnosed with gastrointestinal perforation, and an emergency abdominal operation was performed. A diverticulum with rupture was found in the sigmoid colon, but no apparent tumor was observed. Histological examination revealed bland spindle cells flatly proliferating and diffusely replacing the muscularis propria at the diverticular structure. The spindle cells were positive for KIT, DOG1, and CD34. Mutational analysis of the c-kit gene revealed that the lesion had a heterozygous deletion of 2 amino acids at codons 557 and 558 of exon 11. The mutation was not observed in the normal mucosa of the surrounding tissue. CONCLUSION: We diagnosed this case as an unusual planar-type GIST. Some similar cases have been reported in the sigmoid colon and other sites. We discuss the mechanism of development of the planar-type GISTs associated with the diverticulum.


Assuntos
Colo Sigmoide/patologia , Divertículo/patologia , Neoplasias Gastrointestinais/patologia , Tumores do Estroma Gastrointestinal/patologia , Idoso , Colo Sigmoide/cirurgia , Análise Mutacional de DNA/métodos , Divertículo/cirurgia , Neoplasias Gastrointestinais/genética , Neoplasias Gastrointestinais/cirurgia , Tumores do Estroma Gastrointestinal/genética , Tumores do Estroma Gastrointestinal/cirurgia , Humanos , Masculino , Mutação , Prognóstico , Proteínas Proto-Oncogênicas c-kit/genética
17.
BMC Surg ; 20(1): 27, 2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-32041581

RESUMO

BACKGROUND: Technical factors leading to hernia recurrence after transabdominal preperitoneal repair include insufficient dissection, inadequate prosthetic overlap and prosthetic size, improper fixation and folding, or crinkling of the prosthesis. However, determining intraoperatively if a case will develop recurrent hernias due to these factors remains unclear. METHODS: Five surgeons blind-reviewed operation videos of primary laparoscopic hernioplasty in 13 lesions that went on to develop recurrent hernias (i.e., future recurrence), as well as 28 control lesions, to assess twelve items of surgical techniques. Since we changed a surgical policy of covering myopectineal orifice (MPO) in April 2003, we analyzed the data for the earlier and later periods. The data was analyzed with hierarchical clustering to obtain a gross grouping. The differences of the ratings between the future recurrent and control lesions were then analyzed and the association of the techniques with the hernia recurrence rate, the size of the prosthesis, and the hernia type across hernia recurrence were explored. RESULTS: The lesions were grouped based on the time series, and its boundary was approximated when we changed our surgical policy. This policy change caused ratings to progress from 34% satisfactory, to 79% satisfactory. The recurrence rate decreased to 0.7% (5/678), compared with 6.2% (10/161) before the policy was implemented (p < 0.001). With univariate analysis, the ratings of posterior prosthesis overlap to the MPO in the recurrent lesions were significantly lower than controls in the later period (p = 0.019). Although various types of recurrences were noted in the earlier period, only primary indirect and recurrent indirect hernias were observed in the later period (p = 0.006). CONCLUSIONS: Fully covering the MPO with mesh is essential for preventing direct recurrence hernias. Additional hernia recurrence prevention can be obtained by giving appropriate attention to prosthesis overlap posterior to the MPO in a large indirect hernia.


Assuntos
Hérnia Inguinal/cirurgia , Herniorrafia/métodos , Laparoscopia/métodos , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Implantação de Prótese , Recidiva , Cirurgiões , Telas Cirúrgicas
18.
Shokuhin Eiseigaku Zasshi ; 61(1): 7-16, 2020.
Artigo em Japonês | MEDLINE | ID: mdl-32336720

RESUMO

Total diet study (TDS) is a useful way to estimate the dietary intake of hazardous and chemical substances. Regarding the analysis performed in TDS, international guidelines published by the World Health Organization, recommend selecting and confirming the validity of suitable analytical methods to achieve the purpose of TDS. However, concrete procedures and/or approaches for confirming the validity of suitable methods have yet to be established. In the present study, we aimed to develop samples, referred to as SEMPs; Samples to estimate methods performance, that can be used to evaluate the performance of the analytical methods applied to the composite samples prepared in TDS. The concentrations of 14 kinds of elements, including hazardous substances such as arsenic, lead, and cadmium, in SEMPs were measured for use in the validation of a multi-element analytical method for estimating dietary intake. After examining the appropriate amount of relevant elements added to the samples, we established a performance evaluation procedure by repeatedly analyzing five fortified and non-fortified SEMPs each.


Assuntos
Arsênio/análise , Cádmio/análise , Exposição Dietética/análise , Chumbo/análise , Dieta , Humanos
19.
Shokuhin Eiseigaku Zasshi ; 61(3): 86-94, 2020.
Artigo em Japonês | MEDLINE | ID: mdl-32611948

RESUMO

Most fish contain some kinds of organoarsenic compounds. To assess the health risk for the chronic effects due to intake of these compounds, it is necessary to quantify the concentration of each chemical form, since the toxicity is difference depending on the form. We developed and validated the LC-MS/MS method to determine the concentration of monomethylarsonic acid (MMA), dimethylarsinic acid (DMA), trimethylarsine oxide (TMAO), tetramethylarsonium (TeMA), arsenobetaine (AB), and arsenocholine (AC) in fish. Using this method, we quantified the concentration of each organoarsenic compounds and total arsenic in 50 fish samples from across 10 groups. Total arsenic concentration ranged from 0.53 to 25 mg/kg in all samples, except for in thread-sail filefish where the concentration ranged from 8.3 to 25 mg/kg. With the exception of sardines, in all samples AB was found at the highest level in relation to the total arsenic concentration. In sardines, the concentration of DMA was higher than that of AB, accounting for 16 to 24% of total arsenic. In red sea bream, concentrations of total arsenic, AB, and AC in farm-raised fish were lower than those in wild-caught fish.


Assuntos
Arsênio , Arsenicais , Peixes , Animais , Arsênio/análise , Arsenicais/análise , Cromatografia Líquida , Alimentos Marinhos/análise , Espectrometria de Massas em Tandem
20.
Breast Cancer Res Treat ; 178(2): 283-294, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31402409

RESUMO

PURPOSE: High-density tumor-infiltrating lymphocytes (TILs) are a prognostic marker for triple-negative breast cancer (TNBC). However, lymphocytic infiltration is heterogeneous in its pattern. We aimed to explore the utility of TIL distribution patterns against TIL density for predicting TNBC prognosis and chemotherapeutic effects. METHODS: Primary invasive TNBC cases were retrieved from a single institutional cohort, and archived samples were reviewed by two board-certificated pathologists. We used 154 consecutive surgical specimens from patients with standard adjuvant therapy, and 80 biopsies taken before primary systemic chemotherapy. The average density of stromal TILs was scored at 10% intervals, while the distribution pattern of TILs was evaluated as diffuse or non-diffuse. The association between TILs and prognosis or pathological complete response (pCR) was statistically analyzed. RESULTS: A diffuse pattern of TILs at primary surgery correlated with better prognosis (relapse-free survival [RFS], hazard ratio [HR] 3.71, 95% confidence interval [CI] 1.60-8.57; overall survival [OS], HR 3.87, 95% CI 1.46-10.27), as well as high TIL density (≥ 50%; RFS, HR 4.51, 95% CI 2.06-9.90; OS, HR 3.28, 95% CI 1.32-8.14). Diffuse TIL pattern and nodal status were independent prognostic factors in multivariate analysis. Diffuse TIL pattern upon biopsy was associated with higher pCR rate (diffuse, 46%; non-diffuse, 21%; P = 0.032). All high TIL cases had diffuse patterns and the best outcome. Interobserver concordance was moderate (k = 0.53-0.55; distribution pattern) to good (weighted k = 0.67-0.69; density), and it was faster to assess the distribution pattern than to assess the density of TIL. CONCLUSIONS: Showing similar clinical impacts to the TIL density, diffuse TILs could be a predictive marker for better prognosis and higher pCR. The assessment of TIL distribution pattern is simple, faster, and practical. Heterogeneous tumor immunity may contribute to further stratification of TNBC treatment.


Assuntos
Biomarcadores Tumorais , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Neoplasias de Mama Triplo Negativas/etiologia , Neoplasias de Mama Triplo Negativas/mortalidade , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimioterapia Adjuvante , Feminino , Humanos , Imuno-Histoquímica , Metástase Linfática , Pessoa de Meia-Idade , Terapia Neoadjuvante , Gradação de Tumores , Estadiamento de Neoplasias , Prognóstico , Análise de Sobrevida , Resultado do Tratamento , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/patologia
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