Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 38
Filtrar
1.
Heart ; 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38589224

RESUMO

BACKGROUND: Hypertrophic cardiomyopathy (HCM) is often concomitant with sleep-disordered breathing (SDB), which can cause adverse cardiovascular events. Although an appropriate approach to SDB prevents cardiac remodelling, detection of concomitant SDB in patients with HCM remains suboptimal. Thus, we aimed to develop a machine learning-based discriminant model for SDB in HCM. METHODS: In the present multicentre study, we consecutively registered patients with HCM and performed nocturnal oximetry. The outcome was a high Oxygen Desaturation Index (ODI), defined as 3% ODI >10, which significantly correlated with the presence of moderate or severe SDB. We randomly divided the whole participants into a training set (80%) and a test set (20%). With data from the training set, we developed a random forest discriminant model for high ODI based on clinical parameters. We tested the ability of the discriminant model on the test set and compared it with a previous logistic regression model for distinguishing SDB in patients with HCM. RESULTS: Among 369 patients with HCM, 228 (61.8%) had high ODI. In the test set, the area under the receiver operating characteristic curve of the discriminant model was 0.86 (95% CI 0.77 to 0.94). The sensitivity was 0.91 (95% CI 0.79 to 0.98) and specificity was 0.68 (95% CI 0.48 to 0.84). When the test set was divided into low-probability and high-probability groups, the high-probability group had a higher prevalence of high ODI than the low-probability group (82.4% vs 17.4%, OR 20.9 (95% CI 5.3 to 105.8), Fisher's exact test p<0.001). The discriminant model significantly outperformed the previous logistic regression model (DeLong test p=0.03). CONCLUSIONS: Our study serves as the first to develop a machine learning-based discriminant model for the concomitance of SDB in patients with HCM. The discriminant model may facilitate cost-effective screening tests and treatments for SDB in the population with HCM.

2.
J Virol ; 98(1): e0170223, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38078733

RESUMO

HIV-1 infection of human macrophages leads to the downmodulation of human mannose receptor 1 (hMRC1), a cell-surface glycoprotein that is involved in the host innate immune response. We previously reported that downmodulation of hMRC1 involves the transactivator of transcription (Tat)-dependent transcriptional silencing of the hMRC1 promoter. However, the inhibitory effect of Tat on hMRC1 transcription was indirect and involved inhibition of the transcriptional activator PU.1, which normally upregulates hMRC1 expression in macrophages and other myeloid cells. We cloned a 284-bp fragment of the hMRC1 promoter, and within it, we identified four PU.1 box elements. We assessed the relative contribution of each of the four PU.1 boxes to PU.1-dependent transcriptional regulation and, surprisingly, found that only one of the four PU.1 boxes [PU.1(b)] was critically required for PU.1-mediated upregulation of luciferase expression. Transfer of this PU.1 box to a heterologous promoter conferred PU.1 responsiveness to an otherwise PU.1 insensitive promoter. Electrophoretic mobility shift assays identified this PU.1 box as a direct binding site for PU.1 both in the context of the hMRC1 promoter and the heterologous promoter. Furthermore, mutational analysis of the PU.1 protein identified the C-terminal DNA-binding domain in PU.1 as the region responsible for interaction with the PU.1 box. Recombinant HIV-1 Tat protein did not bind to the hMRC1 promoter element but efficiently interfered with the binding of PU.1 protein to the hMRC1 promoter. Thus, Tat is likely to inhibit the formation of active PU.1 transcription complexes, presumably by binding to and depleting common transcriptional cofactors.IMPORTANCEHIV-1 infection of cells results in the modulation of cellular gene expression by virus-encoded proteins in a manner that benefits the virus. We reported that HIV-1 transactivator of transcription (Tat) dysregulates the expression of the human mannose receptor 1 (hMRC1). hMRC1 is involved in the innate immune response of macrophages to foreign pathogens. Tat does not act directly on the hMRC1 promoter but instead inhibits PU.1, a cellular transcription factor regulating hMRC1 gene expression. Here, we characterize the PU.1-dependent regulation of hMRC1 expression. We identified four potential PU.1 binding sites in the hMRC1 promoter region but found that only one, PU.1(b), functioned as a true binding site for PU.1. Transfer of the PU.1(b) box to a heterologous promoter did not activate this promoter per se but rendered it responsive to PU.1. Our results support the view that PU.1 acts as a transcriptional co-factor whose activity can be regulated by HIV-1 Tat.


Assuntos
HIV-1 , Receptor de Manose , Proteínas Proto-Oncogênicas , Transativadores , Humanos , HIV-1/fisiologia , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Transativadores/genética , Transativadores/metabolismo , Fatores de Transcrição/metabolismo , Transcrição Gênica , Ativação Transcricional
3.
Viruses ; 15(10)2023 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-37896833

RESUMO

Human mannose receptor 1 (hMRC1) is a transmembrane glycoprotein that belongs to the C-type lectin family and is expressed on the surface of most tissue macrophages. hMRC1 contributes to the binding and transmission of HIV-1 and is involved in the endocytic uptake of HIV-1 for subsequent antigen presentation. We previously reported that hMRC1 functions as an antiviral factor by inhibiting virus release through a BST-2-like mechanism. The inhibition of virus release was not virus isolate-specific and, surprisingly, was not Env-dependent. We now report on another hMRC1 antiviral function that affects the infectivity of viral particles. Unlike its effect on virus release, the inhibition of viral infectivity by hMRC1 was virus isolate-specific. An analysis of chimeric Env revealed that the Env V3 region was a critical determinant for the inhibitory effect of hMRC1. Of note, exogenously expressed hMRC1 was packaged into viral particles in an Env-independent manner. Co-immunoprecipitation studies revealed a strong interaction of the hMRC1-sensitive NL43 Env with hMRC1, while the hMRC1-insensitive Envs of AD8 and 49.5 isolates interacted poorly if at all with hMRC1. An analysis of a panel of Transmitted/Founder (T/F) viruses revealed that all of them were R5-tropic, and more than half of them were inhibited by hMRC1. The detailed mechanism of how hMRC1 inhibits viral infectivity remains to be investigated. However, the high-affinity binding of hMRC1 to Env may cause a conformational change around the Env V3 region or obstruct the Env V3 region and may make it inaccessible for subsequent interaction with the coreceptor during virus entry.


Assuntos
Infecções por HIV , HIV-1 , Humanos , Receptor de Manose , HIV-1/genética , Lectinas Tipo C/genética , Antivirais
4.
BMC Musculoskelet Disord ; 24(1): 585, 2023 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-37464323

RESUMO

BACKGROUND: Diabetes mellitus (DM) causes bone dysfunction due to poor bone quality, leading to severe deterioration in patient of quality of life. The mechanisms of bone metabolism in DM remain unclear, although chemical and/or mechanical factors are known to disrupt the homeostasis of osteoblasts and osteoclasts. The purpose of this study was to identify the changes of osteoblasts and osteoclasts under long-term hyperglycaemic conditions, using a mouse fracture model of long-term hyperglycemia (LT-HG). METHODS: C57BL/6J mice and green fluorescent protein (GFP) -positive bone marrow transplanted C57BL/6J mice with LT-HG, maintained under a state of hyperglycaemia for 2 months, were used in this study. After the experimental fracture, we examined the immunohistochemical expression of proinsulin and tumor necrosis factor (TNF) -α at the fracture site. C57BL/6J fracture model mice without hyperglycaemia were used as controls. RESULTS: In the LT-HG mice, chondrocyte resorption was delayed, and osteoblasts showed an irregular arrangement at the callus site. The osteoclasts were scattered with a decrement in the number of nuclei. The expression of proinsulin was confirmed in bone marrow derived cells (BMDCs) with neovascularization 2 and 3 weeks after fracture. Immunopositivity for TNF-α was also confirmed in immature chondrocytes and BMDCs with neovascularization at 2 weeks, and the number of positive cells was not decreased at 3 weeks. Examination of GFP-grafted hyperglycaemic mice showed that the majority of cells at the fracture site were GFP-positive. Immunohistochemistry showed that the rate of double positives was 15% for GFP and proinsulin and 47% for GFP and TNF-α. CONCLUSION: LT-HG induces an increase in the number of proinsulin and TNF-α positive cells derived from BMDCs. We suggest that proinsulin and TNF-α positive cells are involved in both bone formation and bone resorption after fracture under hyperglycaemic conditions, resulting in the delay of bone healing.


Assuntos
Diabetes Mellitus Experimental , Fraturas Ósseas , Hiperglicemia , Animais , Camundongos , Consolidação da Fratura , Citocinas , Fator de Necrose Tumoral alfa/metabolismo , Proinsulina , Medula Óssea/patologia , Diabetes Mellitus Experimental/complicações , Qualidade de Vida , Camundongos Endogâmicos C57BL , Calo Ósseo/patologia , Fraturas Ósseas/patologia , Hiperglicemia/complicações , Hiperglicemia/patologia , Células da Medula Óssea/metabolismo
5.
Arthroplast Today ; 22: 101168, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37497549

RESUMO

Chronic expanding hematoma (CEH) is a rare anatomical condition that gradually expands due to trauma or surgery. We report the case of a 56-year-old woman who developed CEH 25 years after metal-on-polyethylene total hip arthroplasty. She presented with swelling and radiating pain in the right inguinal region. Tocilizumab was administered for treating rheumatoid arthritis and renal amyloid A amyloidosis. Diagnostic imaging and partial resection revealed a soft tissue mass and a CEH, respectively. The symptoms recurred 6 months later; dialysis was initiated, and the CEH was resected under general anesthesia, leading to improvement. This case report emphasizes the importance of prompt diagnosis and intervention in CEH management for preventing further complications and improving the patient's quality of life.

6.
Spine (Phila Pa 1976) ; 48(6): E78-E86, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36729990

RESUMO

STUDY DESIGN: We performed histologic, immunohistochemical, immunoblot examination and suspension array analyses of cytokine expression in cultured cells derived from human cervical ossification of the posterior longitudinal ligament (OPLL). OBJECTIVE: To determine the roles of interleukin-6 (IL-6) during the maturation of osteoblasts and chondrocytes associated with the development of OPLL. SUMMARY OF BACKGROUND DATA: Ectopic OPLL affects ~3% of the general population, with a higher incidence in Asian ethnic groups. Alterations in cytokine profiles may influence osteoblast differentiation, but the mechanisms and signaling pathways associated with the ossification process remain unclear. METHODS: Samples were collected from 14 patients with OPLL who had undergone spinal surgery and seven with cervical spondylotic myelopathy without OPLL. Tissue sections were used for histologic and immunohistochemical studies, and primary cells from ligamentum samples were used for cytokine array and immunoblotting. A suspension array was used to measure the concentrations of 27 inflammatory cytokines or growth factors. RESULTS: Suspension array and immunoblot analyses revealed significantly elevated levels of IL-6 in OPLL patients. Alterations in IL-6 concentrations were found to alter the expression of the genes Sox9 , Runx2 , and SIRT1 . In addition, immunohistochemical analysis revealed that these factors are present in mesenchymal cells within the degenerative portion of the ligament matrix that is adjacent to the ossification front. CONCLUSIONS: IL-6 plays a profound role in the osteoblast differentiation process along with the induction of chondrocyte hypertrophy and cell apoptosis in the early stages of ossification in OPLL. These changes in cytokine profiles are essential factors for regulation of the ectopic ossified plaque in OPLL.


Assuntos
Ligamentos Longitudinais , Ossificação do Ligamento Longitudinal Posterior , Humanos , Diferenciação Celular , Interleucina-6/metabolismo , Ligamentos Longitudinais/patologia , Ossificação do Ligamento Longitudinal Posterior/cirurgia , Osteogênese/genética
7.
mBio ; 14(1): e0297322, 2023 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-36602307

RESUMO

Gelsolin (GSN) is a structural actin-binding protein that is known to affect actin dynamics in the cell. Using mass spectrometry, we identified GSN as a novel Vpr-interacting protein. Endogenous GSN protein was expressed at detectable levels in monocyte-derived macrophages (MDM) and in THP-1 cells, but it was undetectable at the protein level in other cell lines tested. The HIV-1 infection of MDM was associated with a reduction in GSN steady-state levels, presumably due to the Vpr-induced degradation of GSN. Indeed, the coexpression of GSN and Viral protein R (Vpr) in transiently transfected HEK293T cells resulted in the Vpr-dependent proteasomal degradation of GSN. This effect was observed for Vprs from multiple virus isolates. The overexpression of GSN in HEK293T cells had no effect on Gag expression or particle release, but it reduced the expression and packaging of the HIV-1 envelope (Env) glycoprotein and reduced viral infectivity. An analysis of the HIV-1 splicing patterns did not reveal any GSN-dependent differences, suggesting that the effect of GSN on Env expression was regulated at a posttranscriptional level. Indeed, the treatment of transfected cells with lysosomal inhibitors reversed the effect of GSN on Env stability, suggesting that GSN reduced Env expression via enhanced lysosomal degradation. Our data identify GSN as a macrophage-specific host antiviral factor that reduces the expression of HIV-1 Env. IMPORTANCE Despite dramatic progress in drug therapies, HIV-1 infection remains an incurable disease that affects millions of people worldwide. The virus establishes long-lasting reservoirs that are resistant to currently available drug treatments and allow the virus to rebound whenever drug therapy is interrupted. Macrophages are long-lived cells that are relatively insensitive to HIV-1-induced cytopathicity and thus could contribute to the viral reservoir. Here, we identified a novel host factor, gelsolin, that is expressed at high levels in macrophages and inhibits viral infectivity by modulating the expression of the HIV-1 Env glycoprotein, which is critical in the spread of an HIV-1 infection. Importantly, the viral protein Vpr induces the degradation of gelsolin and thus counteracts its antiviral activity. Our study provides significant and novel insights into HIV-1 virus-host interactions and furthers our understanding of the importance of Vpr in HIV-1 infection and pathogenesis.


Assuntos
Infecções por HIV , HIV-1 , Humanos , Produtos do Gene vpr do Vírus da Imunodeficiência Humana/genética , Produtos do Gene vpr do Vírus da Imunodeficiência Humana/metabolismo , Gelsolina/metabolismo , Produtos do Gene env/metabolismo , Células HEK293 , Células Mieloides/metabolismo , Antivirais/metabolismo
8.
J Virol ; 96(14): e0065222, 2022 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-35766490

RESUMO

Human mannose receptor 1 (MRC1) is a cell surface receptor expressed in macrophages and other myeloid cells that inhibits human immunodeficiency virus type 1 (HIV-1) particle release by tethering virions to producer cell membranes. HIV-1 counteracts MRC1 expression by inhibiting mrc1 transcription. Here, we investigated the mechanism of MRC1 downregulation in HIV-1-infected macrophages. We identified the myeloid cell-specific transcription factor PU.1 as critical for regulating MRC1 expression. In the course of our study, we recognized a complex interplay between HIV-1 Tat and PU.1 transcription factors: Tat upregulated HIV-1 gene expression but inhibited mrc1 transcription, whereas PU.1 inhibited HIV-1 transcription but activated MRC1 expression. Disturbing this equilibrium by silencing PU.1 resulted in increased HIV-1 gene expression and reduced MRC1 promoter activity. Our study identified PU.1 as a central player in transcriptional control, regulating a complex interplay between viral and host gene expression in HIV-infected macrophages. IMPORTANCE HIV-1 replication in primary human cells depends on the activity of virus-encoded proteins but also involves cellular factors that can either promote (viral dependency factors) or inhibit (host restriction factors) virus replication. In previous work, we identified human MRC1 as a macrophage-specific host restriction factor that inhibits the detachment of viral particles from infected cells. Here, we report that HIV-1 counteracts this effect of MRC1 by imposing a transcriptional block on cellular MRC1 gene expression. The transcriptional inhibition of the MRC1 gene is accomplished by Tat, an HIV-1 factor whose best-described function actually is the enhancement of HIV-1 gene expression. Thus, HIV-1 has evolved to use the same protein for (i) activation of its own gene expression while (ii) inhibiting expression of MRC1 and other host factors.


Assuntos
Infecções por HIV , Repetição Terminal Longa de HIV , Receptor de Manose , Regulação para Cima , Regulação Viral da Expressão Gênica , Infecções por HIV/fisiopatologia , Infecções por HIV/virologia , HIV-1/fisiologia , Humanos , Macrófagos/virologia , Receptor de Manose/genética , Regiões Promotoras Genéticas , Ativação Transcricional
9.
Sci Rep ; 12(1): 7756, 2022 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-35577902

RESUMO

Uranyl acetate (UA) has been routinely used as a staining solution for ultrathin sections used in biological electron microscopy. As a radioactive nuclear material, UA is subject to strict international regulations. To develop an alternative and easy-to-use staining method for ultrathin sections, we examined various commercial light microscopic dyes. We found that Mayer's hematoxylin followed by Reynold's lead citrate solution showed staining results comparable to UA and Reynold's lead citrate solution, and this method is therefore suggested as a reliable and promising alternative to UA staining.


Assuntos
Corantes , Elétrons , Ácido Cítrico , Hematoxilina , Coloração e Rotulagem
10.
Spine (Phila Pa 1976) ; 47(3): 277-285, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34919077

RESUMO

STUDY DESIGN: Histological, immunohistochemical, and suspension array analyses of cytokine expression in human cervical ossification of the posterior longitudinal ligament (OPLL). OBJECTIVES: The aim of this study was to determine whether changes in the cytokine profile reflect the maturation of chondrocytes and osteoblasts are associated with OPLL development. SUMMARY OF BACKGROUND DATA: OPLL progresses gradually over a prolonged period and may lead to serious spinal cord complications. However, treatment methods only include conservative therapy for neurological symptoms or surgical decompression, whereas preventive therapy for OPLL remains nonexistent. METHODS: Ligamentous samples were harvested from 24 patients with OPLL who underwent spinal surgery, and five control samples from cervical spondylotic myelo/radiculopathy patients without OPLL. Tissue sections were used for immunohistochemical studies and primary cells were cultured from the ligamentous samples for cytokine profiling. Using a suspension array system, concentrations of 27 inflammatory cytokines or growth factors were measured to generate the cytokine profiles. RESULTS: Suspension array and immunoblot analysis revealed significant increments in the levels of interleukin (IL)-6, IL-1α, basic fibroblast growth factor, and RANTES in patients with OPLL. Immunohistochemical analysis further revealed that these factors were present in mesenchymal cells within the degenerative portion of the ligamentous matrix. CONCLUSION: Our findings suggest that specific changes in the cytokine profile during ossification promote osteoblast differentiation, thereby providing new insights into OPLL pathogenesis. Moreover, this work supports the development of a new therapeutic method for preventing OPLL progression by regulating the cytokine profiles.Level of Evidence: 3.


Assuntos
Ligamento Amarelo , Ossificação do Ligamento Longitudinal Posterior , Vértebras Cervicais/cirurgia , Citocinas , Descompressão Cirúrgica , Humanos , Ligamento Amarelo/cirurgia , Ligamentos Longitudinais/cirurgia , Ossificação do Ligamento Longitudinal Posterior/cirurgia , Osteogênese , Resultado do Tratamento
11.
Anticancer Res ; 41(9): 4259-4269, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34475045

RESUMO

BACKGROUND: Compared to two-dimensional cultures, three-dimensional (3D) cultures have many advantages in cancer studies. Nevertheless, their implementation is unsatisfactory. This study aimed to develop an anchorage-dependent 3D culture model for colorectal cancer research. MATERIALS AND METHODS: Human HCT116, DLD-1 and SW620 colorectal cell lines were cultured in a gelatin sponge, and its applicability for morphological examination was studied. RESULTS: The resulting specimens were suitable for scanning electron microscopy, transmission electron microscopy, and immunohistochemical examination. HCT116 formed smaller structures and migrated through the pores of the sponge. DLD-1 formed larger structures with tight cell-to-cell adhesion. SW620 also formed large structures but small clustered cells tended to attach to the anchorage more favorably. Immunohistochemical staining demonstrated phosphorylated yes-associated protein (YAP) localized near the attachment site in HCT116 cells. CONCLUSION: Because the gelatin sponge provided suitable anchorage and the cultured cells formed distinguishable 3D structures, this method may be useful for further colorectal cancer research.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Técnicas de Cultura de Células/métodos , Neoplasias Colorretais/patologia , Gelatina/química , Tecidos Suporte/química , Fatores de Transcrição/metabolismo , Adesão Celular , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Sobrevivência Celular , Neoplasias Colorretais/metabolismo , Células HCT116 , Humanos , Fosforilação , Proteínas de Sinalização YAP
13.
Spine Surg Relat Res ; 5(2): 98-103, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33842717

RESUMO

INTRODUCTION: Posterior lumbar interbody fusion (PLIF) is a widely used effective, safe, and established treatment for degenerative spinal disorders. Adjacent segment disease (ASD) is one of the serious concerns governing the clinical results following spinal fusion surgery. Cortical bone trajectory (CBT) is an alternative and less-invasive technique for lumbar pedicle screw placement. Its unique medial and caudal entry point has the potential to prevent an iatrogenic facet joint violence leading to the ASD; however, the incidence of ASD following PLIF using the CBT technique (CBT-PLIF) remains unknown. METHODS: Among patients surgically treated with CBT-PLIF in our institute, 52 consecutive patients (13 males, 39 females) with single-level degenerative lumbar spondylolisthesis (DLS) who were followed up for at least 24 months were exclusively enrolled. Their clinical and radiological features, including the incidence of radiographical and symptomatic ASD and significantly associated factor for the developing radiographical ASD, were retrospectively measured. RESULTS: In the present study, we could confirm significant neurological improvement and reduction of the spondylolisthesis with mean follow-up period of 43 months. Radiographical and symptomatic ASD was observed in 14 (27%) and 2 (3.8%) cases, respectively. We compared these two groups and found that the latest lumbar lordosis was significantly different between the two groups, but not in age, body mass index, and Japan Orthopaedic Association score. Two patients with symptomatic ASD required additional surgical treatment around 1 year following the initial surgery. CONCLUSIONS: The present study, even though it is preliminary, revealed that CBT-PLIF can achieve a neurological improvement and an effective reduction of spondylolisthesis for the treatment of single-level DLS. The CBT technique is capable of reducing the incidence of ASD compared with the traditional technique; however, we must keep in mind that appropriate postoperative lumbar lordosis should be achieved. Larger, longer-term follow-up studies are required to elucidate the clinical output of CBT-PLIF.

15.
Microbes Infect ; 20(6): 346-352, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29842983

RESUMO

Host factors are required for efficient HIV-1 replication. To identify these factors, genome-wide RNA interference screening was performed using a human T cell line. In the present study, we assessed whether eukaryotic translation initiation factor 4A isoform 2 (eIF4A2), a DEAD-box protein identified in our screen, is necessary for efficient HIV-1 replication. Exploiting MT4C5 cells depleted of eIF4A2 by stable expression of eIF4A2-specific short-hairpin RNA (shRNA) using a lentiviral system, we found that depletion of eIF4A2 markedly inhibited the infection of a replication-competent reporter HIV-1. eIF4A2 depletion reduced the efficiency of viral cDNA synthesis with virion entry into target cells being unaffected. Depletion of eIF4A2 also inhibited HIV-1 spreading infection in a knockdown level-dependent manner. These results suggest that HIV-1 requires eIF4A2 for optimal replication in human T cells.


Assuntos
Fator de Iniciação 4A em Eucariotos/metabolismo , Infecções por HIV/enzimologia , HIV-1/fisiologia , Interações Hospedeiro-Patógeno , Replicação Viral , Linfócitos T CD4-Positivos/enzimologia , Linfócitos T CD4-Positivos/virologia , Linhagem Celular , DNA Viral/biossíntese , Fator de Iniciação 4A em Eucariotos/química , Fator de Iniciação 4A em Eucariotos/deficiência , Fator de Iniciação 4A em Eucariotos/genética , Inativação Gênica , Infecções por HIV/virologia , Humanos , RNA Interferente Pequeno/genética
16.
PLoS One ; 12(9): e0182434, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28873410

RESUMO

Recent studies have identified host cell factors that regulate early stages of HIV-1 infection including viral cDNA synthesis and orientation of the HIV-1 capsid (CA) core toward the nuclear envelope, but it remains unclear how viral DNA is imported through the nuclear pore and guided to the host chromosomal DNA. Here, we demonstrate that N-terminally truncated POM121C, a component of the nuclear pore complex, blocks HIV-1 infection. This truncated protein is predominantly localized in the cytoplasm, does not bind to CA, does not affect viral cDNA synthesis, reduces the formation of 2-LTR and diminished the amount of integrated proviral DNA. Studies with an HIV-1-murine leukemia virus (MLV) chimeric virus carrying the MLV-derived Gag revealed that Gag is a determinant of this inhibition. Intriguingly, mutational studies have revealed that the blockade by N-terminally-truncated POM121C is closely linked to its binding to importin-ß/karyopherin subunit beta 1 (KPNB1). These results indicate that N-terminally-truncated POM121C inhibits HIV-1 infection after completion of reverse transcription and before integration, and suggest an important role for KPNB1 in HIV-1 replication.


Assuntos
HIV-1/fisiologia , Glicoproteínas de Membrana/farmacologia , Replicação Viral/efeitos dos fármacos , Transporte Ativo do Núcleo Celular/efeitos dos fármacos , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Células HEK293 , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , Células HeLa , Humanos , Células Jurkat , Espectrometria de Massas , Glicoproteínas de Membrana/química , Proteínas Mutantes/metabolismo , Ligação Proteica/efeitos dos fármacos , Estrutura Secundária de Proteína , Integração Viral/efeitos dos fármacos , beta Carioferinas/metabolismo , Produtos do Gene gag do Vírus da Imunodeficiência Humana/metabolismo
17.
Intern Med ; 56(16): 2165-2169, 2017 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-28781300

RESUMO

A 50-year-old man presented with exertional dyspnea and orthopnea. An electrocardiogram showed a delta wave and a wide QRS complex, similar to left bundle branch block. Cardiac echocardiography revealed diffuse severe hypokinesis and dyssynchrony. The patient was diagnosed with congestive heart failure. We considered that the patient's condition was caused by an accessory pathway-induced cardiomyopathy after heart failure compensation with guideline-oriented medical therapy. We therefore performed catheter ablation for right-sided pre-excitation syndrome as cardiac resynchronization therapy. The left ventricular dyssynchrony was resolved immediately after the procedure, and the patient's ventricular contraction improved, with a reduced cardiac volume at 6 months after the procedure-thus suggesting that the accessory pathway had affected the patient's cardiac function.


Assuntos
Ablação por Cateter/métodos , Síndrome de Wolff-Parkinson-White/cirurgia , Bloqueio de Ramo/diagnóstico , Terapia de Ressincronização Cardíaca/métodos , Diagnóstico Diferencial , Ecocardiografia , Eletrocardiografia , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Síndrome de Wolff-Parkinson-White/complicações , Síndrome de Wolff-Parkinson-White/diagnóstico
18.
PLoS Pathog ; 13(7): e1006441, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28683086

RESUMO

Regulation of capsid disassembly is crucial for efficient HIV-1 cDNA synthesis after entry, yet host factors involved in this process remain largely unknown. Here, we employ genetic screening of human T-cells to identify maternal embryonic leucine zipper kinase (MELK) as a host factor required for optimal uncoating of the HIV-1 core to promote viral cDNA synthesis. Depletion of MELK inhibited HIV-1 cDNA synthesis with a concomitant delay of capsid disassembly. MELK phosphorylated Ser-149 of the capsid in the multimerized HIV-1 core, and a mutant virus carrying a phosphorylation-mimetic amino-acid substitution of Ser-149 underwent premature capsid disassembly and earlier HIV-1 cDNA synthesis, and eventually failed to enter the nucleus. Moreover, a small-molecule MELK inhibitor reduced the efficiency of HIV-1 replication in peripheral blood mononuclear cells in a dose-dependent manner. These results reveal a previously unrecognized mechanism of HIV-1 capsid disassembly and implicate MELK as a potential target for anti-HIV therapy.


Assuntos
Capsídeo/metabolismo , DNA Viral/genética , Infecções por HIV/enzimologia , HIV-1/fisiologia , Proteínas Serina-Treonina Quinases/metabolismo , Desenvelopamento do Vírus , Linhagem Celular , DNA Viral/metabolismo , Infecções por HIV/genética , Infecções por HIV/virologia , HIV-1/genética , Interações Hospedeiro-Patógeno , Humanos , Leucócitos Mononucleares/enzimologia , Leucócitos Mononucleares/virologia , Fosforilação , Proteínas Serina-Treonina Quinases/genética , Replicação Viral
19.
Asian J Endosc Surg ; 10(3): 282-288, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28176466

RESUMO

INTRODUCTION: The purpose of this study was to evaluate the safety and efficacy of a novel continuous incision technique for the cystic duct and the bile duct over the orifice for laparoscopic transcystic choledocholithotomy (LTCL). METHODS: LTCL was attempted in 103 consecutive patients from January 1998 to March 2015 and was successful in 96 patients. The cystic duct confluence was made by cutting upward from the orifice in 19 patients. The cystic duct was incised downward beyond the orifice to the bile duct in the other 77 patients. Both of these procedures involved LTCL. RESULTS: LTCL was successful in 96 patients. It failed in seven patients because of large bile duct stones (BDS), left lateral entry of the cystic duct, or the cystic duct's small diameter. The success rates of LTCL were 98% (47/48), 96% (42/44), and 64% (7/11) for patients with BDS <10 mm, 10-20 mm, and ≥20 mm, respectively. The success rate for removing BDS <20 mm was significantly higher than the removal rate for BDS ≥20 mm (P < 0.0001). There was no significant difference between the incidences of complications associated with BDS ≥10 mm and with BDS <10 mm (P = 0.49). In those who underwent successful LTCL, complications occurred in 3 of 23 patients with failed preoperative duodenoscopic sphincterotomy and in 9 of the other 73 patients; the incidence of complications did not significantly differ between these groups (P = 0.93). CONCLUSION: LTCL is safe and feasible for exploration of the bile duct and removal of BDS <20 mm.


Assuntos
Coledocolitíase/cirurgia , Ducto Colédoco/cirurgia , Ducto Cístico/cirurgia , Laparoscopia/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Segurança do Paciente , Resultado do Tratamento
20.
Intern Med ; 55(16): 2209-12, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27522996

RESUMO

Hyperthyroidism and thyroid storm affect cardiac circulation in some conditions. Several factors including trauma can induce thyroid storms. We herein describe the case of a 57-year-old woman who experienced a thyroid storm and exacerbation of acute heart failure on thyroid echography. She initially demonstrated a good clinical course after medical rate control for atrial fibrillation; however, thyroid echography for evaluating hyperthyroidism led to a thyroid storm and she collapsed. A multidisciplinary approach stabilized her thyroid hormone levels and hemodynamics. Thus, the medical staff should be prepared for a deterioration in the patient's condition during thyroid echography in heart failure patients with hyperthyroidism.


Assuntos
Insuficiência Cardíaca/etiologia , Crise Tireóidea/etiologia , Glândula Tireoide/diagnóstico por imagem , Ultrassonografia/efeitos adversos , Fibrilação Atrial , Feminino , Humanos , Pessoa de Meia-Idade
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...