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Antiaromatic porphyrinoids have attracted significant attention owing to their unique electronic properties and potential applications. However, synthesis of antiaromatic contracted porphyrinoids is challenging owing to the inherent instability associated with smaller ring sizes. In this study, we report the synthesis and characterization of the first stable trioxa[16]triphyrin(2.1.1), a novel 16π antiaromatic contracted porphyrinoid. We utilized a core modification approach to stabilize the [16]triphyrin(2.1.1). X-ray crystallographic analysis revealed a nearly planar structure. Electrochemical studies demonstrated reversible oxidation behavior and a small HOMO-LUMO gap, which was consistent with its antiaromatic nature. Chemical oxidation yielded an aromatic [14]triphyrin(2.1.1) dication, highlighting the antiaromaticity-aromaticity switching capability of this system. This synthesis involved the discovery of a key intermediate, dihydrotrioxatriphyrin(2.1.1), which underwent oxidative dehydrogenation to yield the target compound. Theoretical calculations suggested that dihydrotrioxatriphyrin(2.1.1) formed via a rare 16π electrocyclic reaction. The successful synthesis and characterization of this stable trioxa[16]triphyrin(2.1.1) underscores the potential of the core modification strategies for the rational design of novel antiaromatic systems with tunable properties. Moreover, the discovery of the rare 16π electrocyclic reaction advances the understanding of high-order pericyclic processes and may inspire new synthetic strategies for complex macrocyclic compounds.
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Many mononegaviruses form inclusion bodies (IBs) in infected cells. However, little is known about nuclear IBs formed by mononegaviruses, since only a few lineages of animal-derived mononegaviruses replicate in the nucleus. In this study, we characterized the IBs formed by Nyamanini virus (NYMV), a unique tick-borne mononegavirus undergoing replication in the nucleus. We discovered that NYMV forms IBs, consisting of condensates and puncta of various sizes and morphologies, in the host nucleus. Likewise, we found that the expressions of NYMV nucleoprotein (N) and phosphoprotein (P) alone induce the formation of condensates and puncta in the nucleus, respectively, even though their morphologies are somewhat different from the IBs observed in the actual NYMV-infected cells. In addition, IB-like structures can be reconstructed by co-expressions of NYMV N and P, and localization analyses using a series of truncated mutants of P revealed that the C-terminal 27 amino acid residues of P are important for recruiting P to the condensates formed by N. Furthermore, we found that nuclear speckles, cellular biomolecular condensates, are reorganized and recruited to the IB-like structures formed by the co-expressions of N and P, as well as IBs formed in NYMV-infected cells. These features are unique among mononegaviruses, and our study has contributed to elucidating the replication mechanisms of nuclear-replicating mononegaviruses and the virus-host interactions.
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Corpos de Inclusão Viral , Nucleoproteínas , Animais , Condensados Biomoleculares , Corpos de Inclusão Viral/metabolismo , Mononegavirais/metabolismo , Nucleoproteínas/genética , Fosfoproteínas/genética , Fosfoproteínas/metabolismoRESUMO
PURPOSE: Vγ9Vδ2 T cells exhibit potent antitumor effects against multiple types of tumors in preclinical models. In the present study, we examined whether human Vγ9Vδ2 T cells can be effective against oral squamous cell carcinoma (OSCC) cell lines in vitro because the interaction between OSCC and Vγ9Vδ2 T cells has not been explored previously. METHODS: Eight OSCC cell lines were analyzed for their expression of ligands that potentially activate Vγ9Vδ2 T cells. Vγ9Vδ2 T cells were expanded in vitro from peripheral blood mononuclear cells (PBMCs) using zoledronate and IL-2. Expanded Vγ9Vδ2 T cells were tested for IFNγ production and cytotoxicity in response to zoledronate-treated OSCC cell lines. Flow cytometry was used to obtain and analyze data. RESULTS: All OSCC cell lines expressed CD277. The cell lines also expressed at least one type of NKG2D ligand. Zoledronate-treated OSCC cell lines induced IFNγ expression in Vγ9Vδ2 T cells. We thus found that Vγ9Vδ2 T cells efficiently kill zoledronate-sensitized OSCC cell lines. CONCLUSIONS: We found that zoledronate-treated OSCC cell lines are effectively killed by Vγ9Vδ2 T cells. Our results indicate that developing Vγ9Vδ2 T cell-based immunotherapy will be promising in treating patients with OSCC.
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Apoptose/efeitos dos fármacos , Carcinoma de Células Escamosas/patologia , Leucócitos Mononucleares/patologia , Neoplasias Bucais/patologia , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , Ácido Zoledrônico/farmacologia , Conservadores da Densidade Óssea/farmacologia , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/metabolismo , Humanos , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Neoplasias Bucais/tratamento farmacológico , Neoplasias Bucais/metabolismo , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Células Tumorais CultivadasRESUMO
Animal-derived RNA viruses frequently generate viral factories in infected cells. However, the details of how RNA viruses build such intracellular structures are poorly understood. In this study, we examined the structure and formation of the viral factories, called viral speckle of transcripts (vSPOTs), that are produced in the nuclei of host cells by Borna disease virus (BDV). Super-resolution microscopic analysis showed that BDV assembled vSPOTs as intranuclear cage-like structures with 59-180-nm pores. The viral nucleoprotein formed the exoskeletons of vSPOTs, whereas the other viral proteins appeared to be mainly localized within these structures. In addition, stochastic optical reconstruction microscopy revealed that filamentous structures resembling viral ribonucleoprotein complexes (RNPs) appeared to protrude from the outer surfaces of the vSPOTs. We also found that vSPOTs disintegrated into RNPs concurrently with the breakdown of the nuclear envelope during mitosis. These observations demonstrated that BDV generates viral replication factories whose shape and formation are regulated, suggesting the mechanism of the integrity of RNA virus persistent infection in the nucleus.
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Vírus da Doença de Borna/metabolismo , Núcleo Celular/metabolismo , Nucleoproteínas/metabolismo , Proteínas Virais/metabolismo , Animais , Linhagem Celular , Núcleo Celular/virologiaRESUMO
Anal metastasis of colorectal cancer is rare, and no standardized effective therapeutic strategy exists. We report a case of abdominoperineal resection for anal metastasis of rectal cancer. A 65-year-old man underwent laparoscopic low anterior resection for rectal cancer in August 2013. Histopathological examination revealed a moderately differentiated adenocarcinoma( tub2, pSS, ly3, v2, pN1, H0, P0, M0, Stage III a, Cur A). In February 2015, he complained of anal discomfort, and tumor markers were elevated. Enhanced CT revealed a 15-mm high-density solid tumor in the anal canal. The results of needle biopsy indicated a moderately differentiated adenocarcinoma. This tumor was suspected to be metastasis from rectal cancer, and we performed abdominoperineal resection. Histopathological examination revealed a moderately differentiated adenocarcinoma, which was the same histological type as the primary rectal cancer and was covered with normal anal epithelium. Collectively, the findings indicated anal metastasis from rectal cancer. The patient is alive without recurrence for 18 months after resection. Anal metastasis should be considered as a differential diagnosis in patients with anal discomfort who have a history of colon/rectal cancer. Abdominoperineal resection may be an effective treatment modality for this condition.
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Adenocarcinoma/cirurgia , Neoplasias do Ânus/cirurgia , Neoplasias Peritoneais/cirurgia , Neoplasias Retais/patologia , Adenocarcinoma/secundário , Idoso , Neoplasias do Ânus/secundário , Humanos , Metástase Linfática , Masculino , Neoplasias Peritoneais/secundário , Prognóstico , Neoplasias Retais/cirurgiaRESUMO
Borna disease virus (BDV) is a non-segmented, negative-strand RNA virus that establishes persistent infection in the nucleus. Although BDV forms viral inclusion bodies, termed viral speckles of transcripts (vSPOTs), which are associated with chromatin in the nucleus, the host factors involved in the maintenance of vSPOTs remain largely unknown. In this study, we identified X-linked RNA-binding motif protein (RBMX) as a nuclear factor interacting with BDV nucleoprotein. Interestingly, knockdown of RBMX led to disruption of the formation of vSPOTs and reduced both transcription and replication of BDV. Our results indicate that RBMX is involved in the maintenance of the structure of the virus factory in the nucleus.
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Vírus da Doença de Borna/metabolismo , Núcleo Celular/virologia , Ribonucleoproteínas Nucleares Heterogêneas/metabolismo , Vírus da Doença de Borna/genética , Núcleo Celular/genética , Núcleo Celular/metabolismo , Ribonucleoproteínas Nucleares Heterogêneas/genética , Interações Hospedeiro-Patógeno , Humanos , Corpos de Inclusão Viral/metabolismo , Nucleoproteínas/genética , Nucleoproteínas/metabolismo , Ligação Proteica , Transporte ProteicoRESUMO
Nine WD-repeat containing proteins in human SSU processome components have been found in a HeLa cell nuclear matrix fraction. In these proteins, t-UTP sub-complex components, i.e., CIRH1A, UTP15, and WDR43, were shown to be immobilized in the fibrillar centers of nucleoli in living cells. In this study, the dynamics of the remaining six proteins fused with green fluorescent protein (GFP), i.e., PWP2-GFP, TBL3-GFP, GFP-UTP18, GFP-NOL10, GFP-WDR46, and GFP-WDSOF1, were examined in living cells. The findings were as follows. (i) The majority of UTP-B sub-complex components, i.e., PWP2-GFP, TBL3-GFP, and GFP-UTP18, are localized to the dense fibrillar component and granular component regions in nucleoli; (ii) When rRNA transcription is suppressed, the majority of GFP-fused UTP-B sub-complex components are localized in the cap and body regions of nucleoli. (iii) The mobility of these proteins except for GFP-WDSOF1, and half of GFP-UTP18 and GFP-WDR46, respectively, is very low in living cells. (iv) When rRNA transcription is suppressed, the mobility of these proteins except for GFP-WDSOF1 is accelerated but still slow. These findings and others suggest that these WD-repeat proteins other than GFP-WDSOF1 found in the nuclear matrix fraction bind tightly to some macro-protein complexes and act as a scaffold or a core for the complexes in nucleoli.
Assuntos
Proteínas Nucleares/química , Proteínas Nucleares/metabolismo , Ribonucleoproteínas/química , Ribonucleoproteínas/metabolismo , Células HeLa , Humanos , Processamento Pós-Transcricional do RNA , RNA Ribossômico/genética , RNA Ribossômico/metabolismoRESUMO
The nuclear scaffold is an insoluble nuclear structure that contributes to the inner nuclear organization. In this study, we showed that one of the nuclear scaffold proteins, WDR46, plays a role as a fundamental scaffold component of the nucleolar structure. WDR46 is a highly insoluble nucleolar protein, and its subcellular localization is dependent on neither DNA nor RNA. The N- and C-terminal regions of WDR46 are predicted to be intrinsically disordered, and both regions are critical for the nucleolar localization of WDR46 and the association with its binding partners. When WDR46 was knocked down, two of its binding partners, nucleolin and DDX21 (involved in 18S rRNA processing), were mislocalized from the granular component to the edges of the nucleoli, whereas other binding partners, NOP2 and EBP2 (involved in 28S rRNA processing), were not affected. This is because the proper recruitment of nucleolin and DDX21 to the nucleoli in daughter cells after cell division is ensured by WDR46. These findings suggest a structural role for WDR46 in organizing the 18S ribosomal RNA processing machinery. This role of WDR46 is enabled by its interaction property via intrinsically disordered regions.
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Antígenos de Neoplasias/metabolismo , RNA Helicases DEAD-box/metabolismo , Fosfoproteínas/metabolismo , Proteínas de Ligação a RNA/metabolismo , Transporte Ativo do Núcleo Celular , Antígenos de Neoplasias/genética , Proteínas de Transporte/metabolismo , Nucléolo Celular/metabolismo , Células HeLa , Humanos , Proteínas Nucleares/metabolismo , Ligação Proteica , RNA Ribossômico 18S/metabolismo , tRNA Metiltransferases/metabolismo , NucleolinaRESUMO
To uncover the molecular composition and dynamics of the functional scaffold for the nucleus, three fractions of biochemically-stable nuclear protein complexes were extracted and used as immunogens to produce a variety of monoclonal antibodies. Many helix-based cytoskeletal proteins were identified as antigens, suggesting their dynamic contribution to nuclear architecture and function. Interestingly, sets of antibodies distinguished distinct subcellular localization of a single isoform of certain cytoskeletal proteins; distinct molecular forms of keratin and actinin were found in the nucleus. Their nuclear shuttling properties were verified by the apparent nuclear accumulations under inhibition of CRM1-dependent nuclear export. Nuclear keratins do not take an obvious filamentous structure, as was revealed by non-filamentous cytoplasmic keratin-specific monoclonal antibody. These results suggest the distinct roles of the helix-based cytoskeletal proteins in the nucleus.
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Anticorpos Monoclonais/análise , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Proteínas do Citoesqueleto/análise , Proteínas do Citoesqueleto/química , Anticorpos Monoclonais/imunologia , Fracionamento Químico , Proteínas do Citoesqueleto/imunologia , Proteínas do Citoesqueleto/metabolismo , Células HeLa , HumanosRESUMO
Objectives: For lung segmentectomy of small lung cancers, we used a microwave surgical instrument for lung parenchymal dissection mainly at the pulmonary hilum, which is difficult to handle with surgical staplers. This technique facilitated the insertion of staples. Methods: In total, 116 patients with cStage 0-1A3 non-small cell lung cancer who underwent lung segmentectomy were included in this study. We compared the perioperative factors of the group in which a microwave surgical instrument was used for dissection procedures, including lung parenchymal dissection at the pulmonary hilum, and peripheral intersegmental dissection was performed with surgical staplers (group M+S: N = 69), with those of the group in which parenchymal dissection was performed mainly with surgical staplers without using the microwave surgical instrument (group S: N = 47). Results: Although more complex segmentectomies were performed in the M+S group (P = .001), the number of staple cartridges (7 staple cartridges vs 8 staple cartridges, P = .005), the surgical times (179 vs 221 minutes, P < .0001), and the blood loss (5 mL vs 30 mL, P = .012) were significantly lower in the M+S group. The duration of chest tube placement was significantly shorter in the M+S group (P = .019), and postoperative complications of grade 2 or greater were significantly lower in the M+S group (P = .049). Conclusions: The effective use of the microwave surgical instrument combined with surgical staplers can simplify pulmonary hilar and intersegmental plane dissections not only for simple segmentectomy but also for complex segmentectomy, leading to favorable intraoperative and postoperative outcomes.
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Membrane-permeable fluorescent dyes that stain DNA are useful reagents for microscopic imaging, as they can be introduced into living cells to label DNA. However, the number of these dyes, such as Hoechst 33342, is limited. Here, we show that the icosahedral dodecaborate B12Br122-, a superchaotropic carrier that delivers different types of molecules into cells, functions as an excellent carrier for membrane-impermeable fluorescent dyes. Propidium iodide (PI) and 4',6-diamidino-2-phenylindole (DAPI), dicationic membrane-impermeable fluorescent dyes that stain DNA, can permeate cell membranes in the presence of boron clusters. Methyl green (MG), a dicationic dye used in the histological and fluorescent staining of DNA, permeated cell membranes in the presence of boron clusters. In contrast, monocationic membrane-permeable fluorescent dyes, such as acridine orange and pyronin Y, exhibited reduced fluorescence in cells in the presence of boron clusters. Boron clusters do not quench dicationic fluorescent dyes in water in vitro but have quenching effects on monocationic fluorescent dyes. We have demonstrated that the addition of B12Br122- to impermeable dicationic fluorescent DNA-staining dyes, such as DAPI, PI, and MG, which have been widely used for numerous years, imparts membrane permeability to introduce these dyes into living cells.
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Inclusion bodies (IBs) are characteristic biomolecular condensates organized by the non-segmented negative-strand RNA viruses belonging to the order Mononegavirales. Although recent studies have revealed the characteristics of IBs formed by cytoplasmic mononegaviruses, that of Borna disease virus 1 (BoDV-1), a unique mononegavirus that forms IBs in the cell nucleus and establishes persistent infection remains elusive. Here, we characterize the IBs of BoDV-1 in terms of liquid-liquid phase separation (LLPS). The BoDV-1 phosphoprotein (P) alone induces LLPS and the nucleoprotein (N) is incorporated into the P droplets in vitro. In contrast, co-expression of N and P is required for the formation of IB-like structure in cells. Furthermore, while BoDV-1 P binds to RNA, an excess amount of RNA dissolves the liquid droplets formed by N and P in vitro. Notably, the intrinsically disordered N-terminal region of BoDV-1 P is essential to drive LLPS and to bind to RNA, suggesting that both abilities could compete with one another. These features are unique among mononegaviruses, and thus this study will contribute to a deeper understanding of LLPS-driven organization and RNA-mediated regulation of biomolecular condensates.
Assuntos
Doença de Borna/metabolismo , Doença de Borna/virologia , Vírus da Doença de Borna/fisiologia , Corpos de Inclusão Viral/metabolismo , Fosfoproteínas/metabolismo , Proteínas Virais/metabolismo , Animais , Condensados Biomoleculares/metabolismo , Condensados Biomoleculares/patologia , Doença de Borna/patologia , Fracionamento Celular/métodos , Células Cultivadas , Imunofluorescência , Corpos de Inclusão Viral/patologia , Extração Líquido-Líquido , Microscopia ConfocalRESUMO
Objective: Pleurodesis is among several treatment strategies for postoperative alveolo-pleural fistula (APF) after lung resection. Accordingly, the present study aimed to determine the influence of pleurodesis on postoperative pulmonary function. Methods: Patients who underwent anatomical segmentectomy between January 2009 and March 2020 and pulmonary function tests 6 and 12 months after initial surgery were included in this study. Differences in pulmonary function decline between patients who did and did not undergo pleurodesis were compared. Results: Among the 319 patients included, 39 (12.2%) underwent pleurodesis. Among patients who did not receive pleurodesis, there were no difference in decline of vital capacity at 6 months (-13.7% ± 1.1% vs -11.2% ± 0.7%; P = .063) and 12 months (-10.7% ± 1.3% vs -9.5% ± 0.7%; P = .391) after surgery between patients who had APF on postoperative day 2 and those who did not. Patients who received pleurodesis had a significantly larger decline in vital capacity at 6 months (-19.4% ± 2.4% vs -13.7% ± 1.1%; P = .015) and 12 months (-16.2% ± 1.6% vs -10.7% ± 1.3%; P = .010) after surgery compared with those who had APF on postoperative day 2 and did not receive pleurodesis. There were no significant differences in decline of forced expiratory volume in 1 second. Conclusions: Pleurodesis negatively influenced postoperative vital capacity after lung segmentectomy. Although the clinical influence of this is unknown, careful consideration is needed before performing pleurodesis given its potential influence on postoperative pulmonary function.
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We present a case of the broncho-pleural fistula with a collapsed lung that was developed 2 weeks after right lower lobectomy. The patient urgently underwent open-window thoracostomy. However, the residual lung remained collapsed. To expand the lung and close the broncho-pleural fistula, negative pressure wound therapy was initiated 20 days after the procedure. The lung expanded within a few days, and the residual thoracic cavity gradually contracted. Subsequently, 2.5 months later, the remaining thoracic cavity was successfully closed using omentoplasty. No recurrence of the broncho-pleural fistula was observed for 1 year. If the lung could be inflated to reduce dead space in the thoracic cavity, broncho-pleural fistula with collapsed lung may be treated with bronchial stump coverage and negative pressure wound therapy.
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Fístula Brônquica , Empiema Pleural , Tratamento de Ferimentos com Pressão Negativa , Doenças Pleurais , Fístula Brônquica/diagnóstico por imagem , Fístula Brônquica/etiologia , Fístula Brônquica/cirurgia , Empiema Pleural/cirurgia , Humanos , Pulmão , Doenças Pleurais/diagnóstico , Doenças Pleurais/etiologia , Doenças Pleurais/cirurgia , PneumonectomiaRESUMO
OBJECTIVE: The clinical practice of safe and efficient surgery and professional development of general thoracic surgical trainee are both important issues for mentors. We investigated the usefulness of a three-dimensional (3D) endoscopic system application for lung cancer treatment as a tool for training surgical trainees. METHODS: Supervised by mentors, general thoracic surgical trainees were trained with video-assisted thoracoscopic surgery (VATS) for primary lung cancer using a 3D endoscopic system to enable them to become operators. Video clinics using 3D images were held weekly. The group using 3D endoscopic system (66 cases in the 3D-VATS group) was compared with the group using conventional two-dimensional (2D) thoracoscopic system (35 cases in the 2D-VATS group) to perform VATS lobectomies. RESULTS: There was no significant difference in operative time between both groups. However, the 3D-VATS group comprised significantly less experience than the 2D-VATS group. The intraoperative blood loss was significantly reduced for the 3D group (34 mL in the 3D-VATS group vs. 76 mL in the 2D-VATS group, P = 0.0007). There were no cases of conversion from VATS to open thoracotomy and intraoperative transfusion in either group. CONCLUSION: 3D-VATS and video clinics using 3D videos are useful training tools for general thoracic surgical trainees with little experience in open thoracotomy.
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Neoplasias Pulmonares , Cirurgia Torácica , Humanos , Neoplasias Pulmonares/cirurgia , Pneumonectomia , Cirurgia Torácica Vídeoassistida , ToracotomiaRESUMO
The RNA helicase, DDX17 is a member of the DEAD-box protein family. DDX17 has two isoforms: p72 and p82. The p82 isoform has additional amino acid sequences called intrinsically disordered regions (IDRs), which are related to the formation of membraneless organelles (MLOs). Here, we reveal that p72 is mostly localized to the nucleoplasm, while p82 is localized to the nucleoplasm and nucleoli. Additionally, p82 exhibited slower intranuclear mobility than p72. Furthermore, the enzymatic mutants of both p72 and p82 accumulate into the stress granules. The enzymatic mutant of p82 abolishes nucleolar localization of p82. Our findings suggest the importance of IDRs and enzymatic activity of DEAD-box proteins in the intracellular distribution and formation of MLOs.
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Nucléolo Celular/metabolismo , Núcleo Celular/metabolismo , RNA Helicases DEAD-box/metabolismo , Organelas/metabolismo , RNA/metabolismo , Neoplasias do Colo do Útero/patologia , Feminino , Células HeLa , Humanos , Isoformas de Proteínas , Neoplasias do Colo do Útero/metabolismoRESUMO
OBJECTIVE: We aimed to investigate the efficacy of complete video-assisted thoracoscopic surgery (cVATS) lobectomy using the three-dimensional (3D) endoscopic system in patients with lung cancer and compare it with that of cVATS lobectomy using the conventional two-dimensional (2D) endoscopic system in former consecutive cases. METHODS: We retrospectively analyzed the prospectively collected database of patients with clinical stage I lung cancer who underwent cVATS lobectomy using the 3D endoscopic system; the patients who underwent surgery using the 2D endoscopic system were considered the historical control group. The operative and perioperative data were compared, and propensity-score matched comparisons were used to assess the potential impact of selection bias. RESULTS: We performed 189 cVATS lobectomies. Of these, 105 were performed using the 3D endoscopic system, while 84 were performed using the 2D endoscopic system. After matching, there was no significant difference in the preoperative factors between the two groups. The operation time was significantly shortened (P = 0.003), and the intraoperative blood loss was significantly reduced in the 3D group (P < 0.001). In particular, there was only one case of intraoperative hemorrhage of 201 mL or more in the 3D group, compared to 12 cases in the 2D group (P < 0.001). After matching, the intraoperative blood loss and operation time were significantly reduced in the 3D group. CONCLUSIONS: Our results showed that the 3D endoscopic system for cVATS lobectomy may be a useful surgical tool and switching to it from the 2D endoscopic system can be performed safely.
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Endoscopia/métodos , Imageamento Tridimensional/métodos , Neoplasias Pulmonares/cirurgia , Pneumonectomia/métodos , Cirurgia Torácica Vídeoassistida/métodos , Idoso , Bases de Dados Factuais , Feminino , Humanos , Pulmão/diagnóstico por imagem , Pulmão/cirurgia , Neoplasias Pulmonares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Período Perioperatório , Pontuação de Propensão , Estudos RetrospectivosRESUMO
Sphingomyelin is a major lipid of the plasma membrane and is enriched in microdomains of the plasma membrane that are critical for signal transduction. However, the function of sphingomyelin in the cell membrane of osteoblasts has not been clarified. Therefore, we examined how sphingomyelin synthase 2 (SMS2) affects osteoclast differentiation by osteoblasts. We knocked down the expression of SMS2 with siRNA targeting the Sgms2 gene in mouse primary osteoblasts. The effects of SMS2 knockdown in osteoblasts were examined using polymerase chain reaction and western blotting. The knockdown of SMS2 suppressed the formation of TRAP-positive multinucleated cells by co-culture of osteoblasts and bone marrow cells compared to the control. We found that receptor activator of nuclear factor κB ligand (RANKL) mRNA expression was significantly reduced by 1,25(OH)2D3 stimulation in SMS2 siRNA osteoblasts. The knockdown of SMS2 repressed the expression of retinoid-X-receptor-α (RXRα) regardless of 1,25(OH)2D3 stimulation. TRAP-positive multinucleated cell formation was significantly reduced by RXRα siRNA in osteoblasts in a co-culture system. These results suggest that SMS2 regulates osteoclast differentiation by inducing RANKL expression via RXRα.
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Regulação da Expressão Gênica , Osteoblastos/metabolismo , Osteogênese/genética , Ligante RANK/genética , Transferases (Outros Grupos de Fosfato Substituídos)/genética , Animais , Diferenciação Celular/genética , Células Cultivadas , Técnicas de Silenciamento de Genes , Inativação Gênica , Camundongos , Osteoclastos/metabolismo , Interferência de RNA , RNA Interferente Pequeno/genética , Receptor X Retinoide alfa/genética , Receptor X Retinoide alfa/metabolismoRESUMO
Borna disease virus (BoDV) is a nonsegmented, negative-strand RNA virus that uniquely replicates and establishes persistent infection in cell nucleus. Recent studies have demonstrated the presence of actin in the nucleus and its role in intranuclear phenomena such as transcription and DNA repair. Although nuclear actin is involved in the life cycle of some intranuclear DNA viruses, the interaction between BoDV and nuclear actin has not been reported. In this study, we show that the inhibition of the nucleocytoplasmic transport of actin affects the replication of BoDV in the nucleus. The knockdown of a nuclear export factor of actin, exportin 6, results in the induction of structural aberration in intranuclear viral factories of BoDV. Furthermore, the inhibition of the nuclear export of actin promotes accumulation of viral matrix protein in the cytoplasm and periphery of the infected cells. These results suggest that the dynamics of actin affect the replication of BoDV by disturbing the structure of viral factories in the nucleus.
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Actinas/metabolismo , Vírus da Doença de Borna/fisiologia , Núcleo Celular/virologia , Interações Hospedeiro-Patógeno , Replicação Viral , Transporte Ativo do Núcleo Celular , Animais , Linhagem Celular , Humanos , Carioferinas/metabolismoRESUMO
Vγ9Vδ2 T cells, the major subset of the human peripheral blood γδ T-cell, respond to microbial infection and stressed cells through the recognition of phosphoantigens. In contrast to the growing knowledge of antigen-mediated activation mechanisms, the antigen-independent and cytokine-mediated activation mechanisms of Vγ9Vδ2 T cells are poorly understood. Here, we show that interleukin (IL) -12 and IL-18 synergize to activate human ex vivo-expanded Vγ9Vδ2 T cells. Vγ9Vδ2 T cells treated with IL-12 and IL-18 enhanced effector functions, including the expression of IFN-γ and granzyme B, and cytotoxicity. These enhanced effector responses following IL-12 and IL-18 treatment were associated with homotypic aggregation, enhanced expression of ICAM-1 and decreased expression of the B- and T-lymphocyte attenuator (BTLA), a co-inhibitory receptor. IL-12 and IL-18 also induced the antigen-independent proliferation of Vγ9Vδ2 T cells. Increased expression of IκBζ, IL-12Rß2 and IL-18Rα following IL-12 and IL-18 stimulation resulted in sustained activation of STAT4 and NF-κB. The enhanced production of IFN-γ and cytotoxic activity are critical for cancer immunotherapy using Vγ9Vδ2 T cells. Thus, the combined treatment of ex vivo-expanded Vγ9Vδ2 T cells with IL-12 and IL-18 may serve as a new strategy for the therapeutic activation of these cells.