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1.
Genes Cells ; 29(1): 39-51, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37963657

RESUMO

The c-Jun N-terminal kinase-associated leucine zipper protein (JLP), a scaffold protein of mitogen-activated protein kinase signaling pathways, is a multifunctional protein involved in a variety of cellular processes. It has been reported that JLP is overexpressed in various types of cancer and is expected to be a potential therapeutic target. However, whether and how JLP overexpression affects non-transformed cells remain unknown. Here, we aimed to investigate the effect of JLP overexpression on chromosomal stability in human non-transformed cells and the mechanisms involved. We found that aneuploidy was induced in JLP-overexpressed cells. Moreover, we established JLP-inducible cell lines and observed an increased frequency of chromosome missegregation, reduced time from nuclear envelope breakdown to anaphase onset, and decreased levels of the spindle assembly checkpoint (SAC) components at the prometaphase kinetochore in cells overexpressing the wild-type JLP. In contrast, we observed that a point mutant JLP lacking the ability to interact with dynein light intermediate chain 1 (DLIC1) failed to induce chromosomal instability. Our results suggest that overexpression of the wild-type JLP facilitates premature SAC silencing through interaction with DLIC1, leading to aneuploidy. This study provides a novel insight into the mechanism through which JLP overexpression is associated with cancer development and progression.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Neoplasias , Humanos , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Zíper de Leucina , Dineínas/genética , Dineínas/metabolismo , Neoplasias/metabolismo , Instabilidade Cromossômica , Aneuploidia , Mitose
2.
Proc Natl Acad Sci U S A ; 118(47)2021 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-34789574

RESUMO

Extrachromosomal circular DNA (eccDNA) originates from linear chromosomal DNA in various human tissues under physiological and disease conditions. The genomic origins of eccDNA have largely been investigated using in vitro-amplified DNA. However, in vitro amplification obscures quantitative information by skewing the total population stoichiometry. In addition, the analyses have focused on eccDNA stemming from single-copy genomic regions, leaving eccDNA from multicopy regions unexamined. To address these issues, we isolated eccDNA without in vitro amplification (naïve small circular DNA, nscDNA) and assessed the populations quantitatively by integrated genomic, molecular, and cytogenetic approaches. nscDNA of up to tens of kilobases were successfully enriched by our approach and were predominantly derived from multicopy genomic regions including segmental duplications (SDs). SDs, which account for 5% of the human genome and are hotspots for copy number variations, were significantly overrepresented in sperm nscDNA, with three times more sequencing reads derived from SDs than from the entire single-copy regions. SDs were also overrepresented in mouse sperm nscDNA, which we estimated to comprise 0.2% of nuclear DNA. Considering that eccDNA can be integrated into chromosomes, germline-derived nscDNA may be a mediator of genome diversity.


Assuntos
DNA Circular , Células Germinativas , Animais , Cromossomos , DNA , Variações do Número de Cópias de DNA , Genoma Humano , Células HeLa , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Duplicações Segmentares Genômicas , Espermatozoides
3.
J Appl Clin Med Phys ; 25(4): e14250, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38146130

RESUMO

BACKGROUND: Organ-at-risk (OAR) sparing is often assessed using an overlap volume-based parameter, defined as the ratio of the volume of OAR that overlaps the planning target volume (PTV) to the whole OAR volume. However, this conventional overlap-based predictive parameter (COPP) does not consider the volume relationship between the PTV and OAR. PURPOSE: We propose a new overlap-based predictive parameter that consider the PTV volume. The effectiveness of proposed overlap-based predictive parameter (POPP) is evaluated compared with COPP. METHODS: We defined as POPP = (overlap volume between OAR and PTV/OAR volume) × (PTV volume/OAR volume). We generated intensity modulated radiation therapy (IMRT) based on step and shoot technique, and volumetric modulated arc therapy (VMAT) plans with the Auto-Planning module of Pinnacle3 treatment planning system (v14.0, Philips Medical Systems, Fitchburg, WI) using the American Association of Physicists in Medicine Task Group (TG119) prostate phantom. The relationship between the position and size of the prostate phantom was systematically modified to simulate various geometric arrangements. The correlation between overlap-based predictive parameters (COPP and POPP) and dose-volume metrics (mean dose, V70Gy, V60Gy, and V37.5 Gy for rectum and bladder) was investigated using linear regression analysis. RESULTS: Our results indicated POPP was better than COPP in predicting intermediate-dose metrics. The bladder results showed a trend similar to that of the rectum. The correlation coefficient of POPP was significantly greater than that of COPP in < 62 Gy (82% of the prescribed dose) region for IMRT and in < 55 Gy (73% of the prescribed dose) region for VMAT regarding the rectum (p < 0.05). CONCLUSIONS: POPP is superior to COPP for creating predictive models at an intermediate-dose level. Because rectal bleeding and bladder toxicity can be associated with intermediate-doses as well as high-doses, it is important to predict dose-volume metrics for various dose levels. POPP is a useful parameter for predicting dose-volume metrics and assisting the generation of treatment plans.


Assuntos
Neoplasias da Próstata , Radioterapia de Intensidade Modulada , Masculino , Humanos , Radioterapia de Intensidade Modulada/métodos , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Órgãos em Risco , Neoplasias da Próstata/radioterapia
4.
Clin Exp Nephrol ; 27(4): 329-339, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36576647

RESUMO

BACKGROUND: Evaluating patients' risk for acute kidney injury (AKI) is crucial for positive outcomes following cardiac surgery. Our aims were first to select candidate risk factors from pre- or intra-operative real-world parameters collected from routine medical care and then evaluate potential associations between those parameters and risk of onset of post-operative cardiac surgery-associated AKI (CSA-AKI). METHOD: We conducted two cohort studies in Japan. The first was a single-center prospective cohort study (n = 145) to assess potential association between 115 clinical parameters collected from routine medical care and CSA-AKI (≥ Stage1) risk in the population of patients undergoing cardiac surgery involving cardiopulmonary bypass (CPB). To select candidate risk factors, we employed random forest analysis and applied survival analyses to evaluate association strength. In a second retrospective cohort study, we targeted patients undergoing cardiac surgery with CPB (n = 619) and evaluated potential positive associations between CSA-AKI incidence and risk factors suggested by the first cohort study. RESULTS: Variable selection analysis revealed that parameters in clinical categories such as circulating inflammatory cells, CPB-related parameters, ventilation, or aging were potential CSA-AKI risk factors. Survival analyses revealed that increased counts of pre-operative circulating monocytes and neutrophils were associated with CSA-AKI incidence. Finally, in the second cohort study, we found that increased pre-operative circulating monocyte counts were associated with increased CSA-AKI incidence. CONCLUSIONS: Circulating monocyte counts in the pre-operative state are associated with increased risk of CSA-AKI development. This finding may be useful in stratifying patients for risk of developing CSA-AKI in routine clinical practice.


Assuntos
Injúria Renal Aguda , Procedimentos Cirúrgicos Cardíacos , Humanos , Estudos de Coortes , Monócitos , Estudos Retrospectivos , Estudos Prospectivos , Ponte Cardiopulmonar/efeitos adversos , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Injúria Renal Aguda/diagnóstico , Injúria Renal Aguda/epidemiologia , Injúria Renal Aguda/etiologia , Fatores de Risco , Complicações Pós-Operatórias/epidemiologia
5.
Nucleic Acids Res ; 49(1): 244-256, 2021 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-33290559

RESUMO

The human genome contains hundreds of large, structurally diverse blocks that are insufficiently represented in the reference genome and are thus not amenable to genomic analyses. Structural diversity in the human population suggests that these blocks are unstable in the germline; however, whether or not these blocks are also unstable in the cancer genome remains elusive. Here we report that the 500 kb block called KRTAP_region_1 (KRTAP-1) on 17q12-21 recurrently demarcates the amplicon of the ERBB2 (HER2) oncogene in breast tumors. KRTAP-1 carries numerous tandemly-duplicated segments that exhibit diversity within the human population. We evaluated the fragility of the block by cytogenetically measuring the distances between the flanking regions and found that spontaneous distance outliers (i.e DNA breaks) appear more frequently at KRTAP-1 than at the representative common fragile site (CFS) FRA16D. Unlike CFSs, KRTAP-1 is not sensitive to aphidicolin. The exonuclease activity of DNA repair protein Mre11 protects KRTAP-1 from breaks, whereas CtIP does not. Breaks at KRTAP-1 lead to the palindromic duplication of the ERBB2 locus and trigger Breakage-Fusion-Bridge cycles. Our results indicate that an insufficiently investigated area of the human genome is fragile and could play a crucial role in cancer genome evolution.


Assuntos
Neoplasias da Mama/genética , Sítios Frágeis do Cromossomo/genética , Reparo do DNA , Amplificação de Genes , Duplicação Gênica/genética , Genes erbB-2 , Queratinas Específicas do Cabelo/fisiologia , Afidicolina/farmacologia , Mama/metabolismo , Neoplasias da Mama/metabolismo , Células Cultivadas , Instabilidade Cromossômica , Quebras de DNA , Variações do Número de Cópias de DNA , DNA de Neoplasias/genética , Células Epiteliais/metabolismo , Feminino , Variação Genética , Instabilidade Genômica , Humanos , Proteína Homóloga a MRE11/fisiologia , Proteínas de Neoplasias/fisiologia , Sequenciamento Completo do Genoma
6.
Kyobu Geka ; 75(3): 189-192, 2022 Mar.
Artigo em Japonês | MEDLINE | ID: mdl-35249951

RESUMO

A 73-year-old man had Stanford type B acute aortic dissection 11 years before. He had underwent thoracoabdominal aortic replacement due to thoracoabdominal aneurysm nine years before and hemiarch aortic replacement due to Stanford type A acute aortic dissection four years before. We performed surgery because the dissecting aortic aneurysm in the distal arch has enlarged. We selected thoracic endovascular aortic repair( TEVAR) because of reoperation, but the true lumen of the descending aorta was highly narrowed, we had to deploy stent-grafts into the false lumen. Since the proximal and distal parts of endovascular thoracic stent-grafts were deployed into the previously implanted Dacron grafts, we could deploy them without vascular injury. If both proximal and distal parts of stent-grafts can be deployed into vascular prosthesis, deploying the stent-grafts into the false lumen may be a feasible option.


Assuntos
Aneurisma da Aorta Torácica , Implante de Prótese Vascular , Procedimentos Endovasculares , Idoso , Aneurisma da Aorta Torácica/diagnóstico por imagem , Aneurisma da Aorta Torácica/cirurgia , Prótese Vascular , Humanos , Masculino , Estudos Retrospectivos , Stents , Resultado do Tratamento
7.
Hepatol Res ; 51(8): 870-879, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33894086

RESUMO

AIM: To report the outcomes of stereotactic body radiotherapy using a real-time tumor-tracking radiotherapy system for hepatocellular carcinoma patients. METHODS: From January 2005 to July 2018, 63 patients with 74 lesions with a maximum diameter ≤52 mm were treated by stereotactic body radiotherapy using a real-time tumor-tracking radiotherapy system. No patient with a Child-Pugh Score ≥9 was included, and 85.6% had a score of 5 or 6. Using the biological effective dose (BED) with an α/ß ratio of 10 (BED10 ), the median dose in BED10 at the reference point was 76.8 Gy (range 60-122.5 Gy). Overall survival (OS) and local control rates were assessed using the Kaplan-Meier method. RESULTS: With a median follow-up period of 24.6 months (range 0.9-118.4 months), the 1-year and 2-year OS rates were 86.8% (95% confidence interval [95% CI] 75.8-93.3) and 71.1% (57.8-81.6), respectively. The 2-year OS was 89.6% in patients with the baseline modified albumin-bilirubin (mALBI) grade =1, and 61.7% in patients with grade ≥2a. In the multivariate analysis, the mALBI grade (=1 vs. ≥2a) was a significant factor for OS (p = 0.028, 95% CI 1.11-6.18). The 1-year and 2-year local control rates were 100% (100-100%) and 92.0% (77.5-97.5%). The local control rates were significantly higher in the BED10 ≥100 Gy group than in the BED10 <100 Gy group (2-year 100% vs. 86.5%, p = 0.049) at the reference point. CONCLUSION: This retrospective study of stereotactic body radiotherapy using real-time tumor-tracking radiotherapy for hepatocellular carcinoma showed favorable outcomes with lower incidence of toxicities, especially in patients treated with BED10 ≥100 Gy to the reference point.

8.
Heart Vessels ; 36(4): 577-588, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33180177

RESUMO

This investigation was aimed to identify gene profiles in human atrial myocardium in response to chronic mechanical stretch. Right atrial appendages from 21 patients were divided into 2 groups based on the size of right atrial volume. The microarray DATA analyses differentially identified 335 genes (> 2.0-fold, corrected P < 0.05) including "functionally unknown genes". This study identified 26 up-regulated genes (natriuretic peptide B, G protein subunit gamma 13, thyroid stimulating hormone beta, etc.) and 23 down-regulated genes (oligodendrocyte transcription factor 1, carbonic anhydrase 12, etc.), which could be responsible for chronic stretch-mediated structural remodeling in the atrium.


Assuntos
Regulação da Expressão Gênica , Átrios do Coração/metabolismo , Miocárdio/metabolismo , Proteínas do Tecido Nervoso/genética , RNA/genética , Transcriptoma/genética , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas do Tecido Nervoso/biossíntese , Estresse Mecânico
9.
J Med Internet Res ; 23(1): e14794, 2021 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-33464211

RESUMO

BACKGROUND: An increasing number of people are visiting hospital websites to seek better services and treatments compared to the past. It is therefore important for hospitals to develop websites to meet the needs of their patients. However, few studies have investigated whether and how the current hospital websites meet the patient's needs. Above all, in radiation departments, it may be difficult for patients to obtain the desired information regarding modality and diagnosis because such information is subdivided when described on a website. OBJECTIVE: The purpose of this study is to suggest a hospital website search behavior model by analyzing the browsing behavior model using a Bayesian network from the perspective of one-to-one marketing. METHODS: First, we followed the website access log of Hokkaido University Hospital, which was collected from September 1, 2016, to August 31, 2017, and analyzed the access log using Google Analytics. Second, we specified the access records related to radiology from visitor browsing pages and keywords. Third, using these resources, we structured 3 Bayesian network models based on specific patient needs: radiotherapy, nuclear medicine examination, and radiological diagnosis. Analyzing each model, this study considered why some visitors could not reach their desired page and improvements to meet the needs of visitors seeking radiology-related information. RESULTS: The radiotherapy model showed that 74% (67/90) of the target visitors could reach their requested page, but only 2% (2/90) could reach the Center page where inspection information, one of their requested pages, is posted. By analyzing the behavior of the visitors, we clarified that connecting with the radiotherapy and radiological diagnosis pages is useful for increasing the proportion of patients reaching their requested page. CONCLUSIONS: We proposed solutions for patient web-browsing accessibility based on a Bayesian network. Further analysis is necessary to verify the accuracy of the proposed model in comparison to other models. It is expected that information provided on hospital websites will be improved using this method.


Assuntos
Radiologia/educação , Design Centrado no Usuário , Teorema de Bayes , Hospitais , Humanos , Internet , Projetos de Pesquisa , Inquéritos e Questionários
10.
J Acoust Soc Am ; 149(2): 1030, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33639818

RESUMO

There was a previous study to derive the sound absorption coefficient of the powder layers comprising powder particles with a diameter of a few tens of µm. According to this previous method, the impact of air viscosity at the boundary layer generated in the pores between the powder particles is neglected. Therefore, precision is not guaranteed when the particle diameter is relatively large or when the density is relatively high. In the present study, to obtain the sound absorption coefficient of the powder layer more accurately, in addition to the above-described longitudinal vibration mode, the energy damping property of the boundary layer viscosity was calculated using the transfer-matrix method. As a result, when the longitudinal vibration mode and boundary layer viscosity were considered, the theoretical value tended to be closer to the experimental value than when only the longitudinal vibration was considered.

11.
J Appl Clin Med Phys ; 22(7): 165-176, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34080303

RESUMO

PURPOSE: The real-time tumor tracking radiotherapy (RTRT) system requires periodic quality assurance (QA) and quality control. The goal of this study is to propose QA procedures from the viewpoint of imaging devices in the RTRT system. METHODS: Tracking by the RTRT system (equips two sets of colored image intensifiers (colored I.I.s) fluoroscopy units) for the moving gold-marker (diameter 2.0 mm) in a rotating phantom were performed under various X-ray conditions. To analyze the relationship between fluoroscopic image quality and precision of gold marker coordinate calculation, the standard deviation of the 3D coordinate (σ3D [mm]) of the gold marker, the mean of the pattern recognition score (PRS) and the standard deviation of the distance between rays (DBR) (σDBR [mm]) were evaluated. RESULTS: When tracking with speed of 10-60 mm/s, σDBR increased, though the mean PRS did not change significantly (p>0.05). On the contrary, the mean PRS increased depending on the integral noise equivalent quanta (∫NEQ) that is an indicator of image quality calculated from the modulation transfer function (MTF) as an indicator of spatial resolution and the noise power spectrum (NPS) as an indicator of noise characteristic. CONCLUSION: The indicators of NEQ, MTF, and NPS were useful for managing the tracking accuracy of the RTRT system. We propose observing the change of these indicators as additional QA procedures for each imaging device from the commissioning baseline.


Assuntos
Neoplasias , Radioterapia (Especialidade) , Fluoroscopia , Humanos , Neoplasias/diagnóstico por imagem , Neoplasias/radioterapia , Imagens de Fantasmas , Intensificação de Imagem Radiográfica
12.
J Appl Clin Med Phys ; 22(1): 174-183, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33338323

RESUMO

PURPOSE: To investigate potential advantages of adaptive intensity-modulated proton beam therapy (A-IMPT) by comparing it to adaptive intensity-modulated X-ray therapy (A-IMXT) for nasopharyngeal carcinomas (NPC). METHODS: Ten patients with NPC treated with A-IMXT (step and shoot approach) and concomitant chemotherapy between 2014 and 2016 were selected. In the actual treatment, 46 Gy in 23 fractions (46Gy/23Fx.) was prescribed using the initial plan and 24Gy/12Fx was prescribed using an adapted plan thereafter. New treatment planning of A-IMPT was made for the same patients using equivalent dose fractionation schedule and dose constraints. The dose volume statistics based on deformable images and dose accumulation was used in the comparison of A-IMXT with A-IMPT. RESULTS: The means of the Dmean of the right parotid gland (P < 0.001), right TM joint (P < 0.001), left TM joint (P < 0.001), oral cavity (P < 0.001), supraglottic larynx (P = 0.001), glottic larynx (P < 0.001), , middle PCM (P = 0.0371), interior PCM (P < 0.001), cricopharyngeal muscle (P = 0.03643), and thyroid gland (P = 0.00216), in A-IMPT are lower than those of A-IMXT, with statistical significance. The means of, D0.03cc , and Dmean of each sub portion of auditory apparatus and D30% for Eustachian tube and D0.5cc for mastoid volume in A-IMPT are significantly lower than those of A-IMXT. The mean doses to the oral cavity, supraglottic larynx, and glottic larynx were all reduced by more than 20 Gy (RBE = 1.1). CONCLUSIONS: An adaptive approach is suggested to enhance the potential benefit of IMPT compared to IMXT to reduce adverse effects for patients with NPC.


Assuntos
Neoplasias Nasofaríngeas , Terapia com Prótons , Radioterapia de Intensidade Modulada , Humanos , Carcinoma Nasofaríngeo/radioterapia , Neoplasias Nasofaríngeas/radioterapia , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador
13.
Kyobu Geka ; 74(11): 962-965, 2021 Oct.
Artigo em Japonês | MEDLINE | ID: mdl-34601483

RESUMO

A 76-year-old woman underwent screening echocardiography. A cardiac mass was detected in the left atrium. It was located at the atrial septum, and was around 3 cm in size. Its surface was smooth and there was cystic cavity inside. Coronary angiography revealed rich blood flow from bilateral coronary arteries to the mass and massive shunt to the left atrium, which formed a fistulous connection. We performed tumor resection under cardiopulmonary bypass. Postoperative course was uneventful. Histopathologically, the tumor was myxoma. Cardiac myxoma is the most common primary cardiac tumor, but myxoma exhibiting coronary artery-left atrial fistula is fairly uncommon.


Assuntos
Fístula , Neoplasias Cardíacas , Mixoma , Idoso , Vasos Coronários/diagnóstico por imagem , Vasos Coronários/cirurgia , Feminino , Fístula/diagnóstico por imagem , Fístula/cirurgia , Átrios do Coração/diagnóstico por imagem , Átrios do Coração/cirurgia , Neoplasias Cardíacas/complicações , Neoplasias Cardíacas/diagnóstico por imagem , Neoplasias Cardíacas/cirurgia , Humanos , Mixoma/complicações , Mixoma/diagnóstico por imagem , Mixoma/cirurgia
14.
Kyobu Geka ; 74(6): 424-428, 2021 Jun.
Artigo em Japonês | MEDLINE | ID: mdl-34059584

RESUMO

We report a case of a ruptured coronary artery aneurysm. An 87-year-old woman suffered from cardiac tamponade due to a ruptured coronary artery aneurysm. Coronary angiography showed a giant coronary aneurysm without coronary artery fistula. Emergency surgery was performed through median sternotomy. We performed aneurysmectomy and ligation of the perfusion arteries under cardiopulmonary bypass. The patient's postoperative course was uneventful. We also reviewed nine cases of ruptured coronary artery aneurysm without coronary artery fistula in Japan. The disease is a rare clinical state and considered to be an indication for emergency surgery.


Assuntos
Tamponamento Cardíaco , Aneurisma Coronário , Idoso de 80 Anos ou mais , Tamponamento Cardíaco/diagnóstico por imagem , Tamponamento Cardíaco/etiologia , Tamponamento Cardíaco/cirurgia , Aneurisma Coronário/complicações , Aneurisma Coronário/diagnóstico por imagem , Aneurisma Coronário/cirurgia , Angiografia Coronária , Vasos Coronários/diagnóstico por imagem , Vasos Coronários/cirurgia , Feminino , Humanos , Japão
15.
Biochem Biophys Res Commun ; 522(3): 697-703, 2020 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-31787236

RESUMO

Previous studies have established the antitumor activity of curcumin, a major component of turmeric. Increasing evidence indicates that curcumin induces autophagy, the activation of mitogen-activated protein kinase (MAPK) intracellular signaling pathways, and reactive oxygen species (ROS)-mediated cell death. The c-Jun NH2-terminal kinase (JNK)-associated leucine zipper protein (JLP), a scaffold protein for MAPK signaling pathways, has been identified as a candidate biomarker for cancer. In this study, we explored the role of JLP in curcumin-induced cancer cell death. We found that JLP knockdown (KD) increases cell death and intracellular ROS levels. Furthermore, JLP KD impaired lysosomal accumulation around perinuclear regions, which led to the inhibition of autophagosome-lysosome fusion, and attenuated p38 MAPK activation in curcumin-treated cells. The decreases in cell viability and p38 MAPK activation were reversed by expressing wild-type JLP but not a JLP mutant lacking the p38 MAPK-binding domain. In addition, the inactivation of a key gene involved in autophagy increased sensitivity to curcumin-induced cell death. Together, these results suggest that JLP mediates the induction of autophagy by regulating lysosome positioning and p38 MAPK signaling, indicating an overall protective role in curcumin-induced ROS-mediated cancer cell death.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Antineoplásicos/farmacologia , Curcumina/farmacologia , Neoplasias/tratamento farmacológico , Autofagia/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Neoplasias/metabolismo , Espécies Reativas de Oxigênio/metabolismo
16.
J Neurosci ; 38(6): 1366-1382, 2018 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-29279310

RESUMO

Spinal cord injury (SCI) induces a centralized fibrotic scar surrounded by a reactive glial scar at the lesion site. The origin of these scars is thought to be perivascular cells entering lesions on ingrowing blood vessels and reactive astrocytes, respectively. However, two NG2-expressing cell populations, pericytes and glia, may also influence scar formation. In the periphery, new blood vessel growth requires proliferating NG2+ pericytes; if this were also true in the CNS, then the fibrotic scar would depend on dividing NG2+ pericytes. NG2+ glial cells (also called oligodendrocyte progenitors or polydendrocytes) also proliferate after SCI and accumulate in large numbers among astrocytes in the glial scar. Their effect there, if any, is unknown. We show that proliferating NG2+ pericytes and glia largely segregate into the fibrotic and glial scars, respectively; therefore, we used a thymidine kinase/ganciclovir paradigm to ablate both dividing NG2+ cell populations to determine whether either scar was altered. Results reveal that loss of proliferating NG2+ pericytes in the lesion prevented intralesion angiogenesis and completely abolished the fibrotic scar. The glial scar was also altered in the absence of acutely dividing NG2+ cells, displaying discontinuous borders and significantly reduced GFAP density. Collectively, these changes enhanced edema, prolonged hemorrhage, and impaired forelimb functional recovery. Interestingly, after halting GCV at 14 d postinjury, scar elements and vessels entered the lesions over the next 7 d, as did large numbers of axons that were not present in controls. Collectively, these data reveal that acutely dividing NG2+ pericytes and glia play fundamental roles in post-SCI tissue remodeling.SIGNIFICANCE STATEMENT Spinal cord injury (SCI) is characterized by formation of astrocytic and fibrotic scars, both of which are necessary for lesion repair. NG2+ cells may influence both scar-forming processes. This study used a novel transgenic mouse paradigm to ablate proliferating NG2+ cells after SCI to better understand their role in repair. For the first time, our data show that dividing NG2+ pericytes are required for post-SCI angiogenesis, which in turn is needed for fibrotic scar formation. Moreover, loss of cycling NG2+ glia and pericytes caused significant multicellular tissue changes, including altered astrocyte responses and impaired functional recovery. This work reveals previously unknown ways in which proliferating NG2+ cells contribute to endogenous repair after SCI.


Assuntos
Antígenos/genética , Axônios/patologia , Cicatriz/genética , Neovascularização Patológica/genética , Proteoglicanas/genética , Traumatismos da Medula Espinal/genética , Traumatismos da Medula Espinal/patologia , Animais , Astrócitos/patologia , Proliferação de Células/efeitos dos fármacos , Cicatriz/patologia , Fibrose/patologia , Proteína Glial Fibrilar Ácida/biossíntese , Proteína Glial Fibrilar Ácida/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neovascularização Patológica/patologia , Neuroglia/metabolismo , Neuroglia/patologia , Pericitos/metabolismo , Pericitos/patologia , Recuperação de Função Fisiológica/genética
17.
J Acoust Soc Am ; 146(4): 2253, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31671960

RESUMO

In this study, the sound absorption characteristics of lightweight powders with a particle size on the order of tens of micrometers have been investigated. Herein, to theoretically determine the sound absorption coefficient of a fine lightweight powder in the longitudinal vibration mode, it was assumed that the powder was continuum and could be treated as a multiple degree-of-freedom damping vibration system. In addition, the acoustic impedance was calculated by assuming proportional viscous damping to determine the sound absorption coefficient. Finally, the theoretical and experimental values were compared. With the presented theoretical analysis, values close to the experimental results were obtained. Among the three calculated values based on proportional viscous damping, i.e., Rayleigh damping, rigidity proportional damping, and mass proportional damping, the results for Rayleigh damping were the closest to the experimental values.

18.
J Appl Clin Med Phys ; 20(8): 78-86, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31400082

RESUMO

PURPOSE: Interplay effects may influence dose distributions to a moving target when using dynamic delivery techniques such as intensity-modulated radiotherapy (IMRT). The aim of this study was to evaluate the impact of organ motion on volumetric and dosimetric parameters in stomach lymphomas treated with IMRT. METHODS: Ten patients who had been treated with IMRT for stomach lymphomas were enrolled. The clinical target volume (CTV) was contoured as the whole stomach. Considering interfractional uncertainty, the internal target volume (ITV) margin was uniformly 1.5 cm to the CTV and then modified based on the 4DCT images in case of the large respiratory motion. The planning target volume (PTV) was created by adding 5 mm to the ITV. The impact of organ motion on the volumetric and dosimetric parameters was evaluated retrospectively (4D simulation). The organ motion was reproduced by shifting the isocenter on the radiation treatment planning system. Several simulation plans were created to test the influence of the beam-on timing in the respiration cycle on the dose distribution. The homogeneity index (HI), volume percentage of stomach covered by the prescribed dose (Vp ), and D99 of the CTV were evaluated. RESULTS: The organ motion was the largest in the superior-inferior direction (10.1 ± 4.5 mm [average ± SD]). Stomach volume in each respiratory phase compared to the mean volume varied approximately within a ± 5% range in most of the patients. The PTV margin was sufficiently large to cover the CTV during the IMRT. There was a significant reduction in Vp and D99 but not in HI in the 4D simulation in free-breathing and multiple fractions compared to the clinically-used plan (P < 0.05) suggesting that interplay effects deteriorate the dose distribution. The absolute difference of D99 was less than 1% of the prescribed dose. CONCLUSIONS: There were significant interplay effects affecting the dose distribution in stomach IMRT. The magnitude of the dose reduction was small when patients were treated on free-breathing and multiple fractions.


Assuntos
Linfoma/radioterapia , Movimentos dos Órgãos , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos , Respiração , Neoplasias Gástricas/radioterapia , Humanos , Linfoma/fisiopatologia , Órgãos em Risco/efeitos da radiação , Prognóstico , Dosagem Radioterapêutica , Estudos Retrospectivos , Neoplasias Gástricas/fisiopatologia
19.
Biochem Biophys Res Commun ; 501(3): 724-730, 2018 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-29753743

RESUMO

Oxidative stress, which can be caused by an overproduction of reactive oxygen species (ROS), often leads to cell death. In recent years, c-Jun NH2-terminal kinase (JNK)-associated leucine zipper protein (JLP, also known as SPAG9 or JIP4), a scaffold protein for JNK mitogen-activated protein kinase (MAPK) signaling pathways, was found to serve as a novel biomarker for cancer. However, although JNK MAPK pathways are reported to be activated in response to various stimuli, including oxidative stress, whether JLP is involved in ROS signaling remains unknown. In this study, we examined the role of JLP in hydrogen peroxide (H2O2)-induced cancer cell death, and found that JLP knockdown (KD) cells exhibit a substantially enhanced cell death response, along with increased intracellular ROS levels. This is the first demonstration of a protective role for JLP in response to cell-death stimulation. We also found that the H2O2-induced JNK activation was attenuated in JLP KD cancer cells. The decreases in cell viability and JNK activation in the JLP KD cells were almost completely reversed by expressing wild-type JLP, but not a mutant JLP lacking the JNK-binding domain. These data collectively suggest that the JLP-JNK signaling pathway counteracts ROS-induced cancer cell death.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Sistema de Sinalização das MAP Quinases , Neoplasias/metabolismo , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Morte Celular , Linhagem Celular Tumoral , Humanos , Peróxido de Hidrogênio/metabolismo , Neoplasias/patologia
20.
Echocardiography ; 35(4): 573-574, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29505659

RESUMO

We detected symptomatic atrial fibrillation in a 64-year-old man who had undergone mitral valvuloplasty. While performing transesophageal echocardiography (TEE) in the left lateral decubitus position, we detected an isoechoic mass lesion at the bottom of the left atrial appendage (LAA). After changing the patient's position from left to right, the mass lesion dropped down from the bottom of the LAA, spread out into the left atrium, and appeared as a spontaneous echocardiographic contrast with mobility. We therefore diagnosed the mass lesion as not a thrombus but sludge. Changing the patient's position during TEE is useful for distinguishing sludge from thrombi.


Assuntos
Apêndice Atrial/diagnóstico por imagem , Apêndice Atrial/fisiopatologia , Fibrilação Atrial/fisiopatologia , Ecocardiografia Transesofagiana/métodos , Posicionamento do Paciente/métodos , Trombose , Diagnóstico Diferencial , Humanos , Masculino , Pessoa de Meia-Idade , Postura
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