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1.
Data Brief ; 54: 110313, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38524841

RESUMO

The present data are subsurface velocity structures retrieved by applying the theory of diffuse field concept to the strong motion data of earthquakes observed at 1744 sites of K-NET and KiK-net (operated by the National Institute of Earth Science and Disaster Resilience) in Japan. Additionally, the data include peak fundamental and predominant frequencies as identified from the observed and theoretical horizontal-to-vertical spectral ratios for earthquakes (eHVSR). Based on our novel proposed quarter wavelength approach, we could define the effective bedrock depths and correlate them with the corresponding peak frequencies. For better usefulness of the present data, we classify the sites into four categories based on the correlation coefficients and residuals between the observed and theoretical eHVSR. The potentiality of these data could be reused by other researchers to develop new approaches related to the limitations of the established bedrock regressions and the uncertainty associated with the retrieved subsurface velocity structures, particularly at sites with low correlation coefficients and high residuals. Moreover, the data of the subsurface velocity structures could be reused as initial models for future microtremor applications and better enhance the retrieved velocity structures and the associated theoretical eHVSR curves. The data of the present paper is associated with original published article by Thabet et al. [1], which is presented in the Soil Dynamics and Earthquake Engineering under the title "A computational approach for bedrock regressions with diffuse field concept beneath the Japan Islands" [1].

2.
Hum Mol Genet ; 32(16): 2600-2610, 2023 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-37260376

RESUMO

Friedreich's ataxia (FA) is a devastating, multi-systemic neurodegenerative disease affecting thousands of people worldwide. We previously reported that oxygen is a key environmental variable that can modify FA pathogenesis. In particular, we showed that chronic, continuous normobaric hypoxia (11% FIO2) prevents ataxia and neurological disease in a murine model of FA, although it did not improve cardiovascular pathology or lifespan. Here, we report the pre-clinical evaluation of seven 'hypoxia-inspired' regimens in the shFxn mouse model of FA, with the long-term goal of designing a safe, practical and effective regimen for clinical translation. We report three chief results. First, a daily, intermittent hypoxia regimen (16 h 11% O2/8 h 21% O2) conferred no benefit and was in fact harmful, resulting in elevated cardiac stress and accelerated mortality. The detrimental effect of this regimen is likely owing to transient tissue hyperoxia that results when daily exposure to 21% O2 combines with chronic polycythemia, as we could blunt this toxicity by pharmacologically inhibiting polycythemia. Second, we report that more mild regimens of chronic hypoxia (17% O2) confer a modest benefit by delaying the onset of ataxia. Third, excitingly, we show that initiating chronic, continuous 11% O2 breathing once advanced neurological disease has already started can rapidly reverse ataxia. Our studies showcase both the promise and limitations of candidate hypoxia-inspired regimens for FA and underscore the need for additional pre-clinical optimization before future translation into humans.


Assuntos
Ataxia de Friedreich , Doenças Neurodegenerativas , Policitemia , Humanos , Camundongos , Animais , Ataxia de Friedreich/genética , Modelos Animais de Doenças , Hipóxia , Oxigênio , Ataxia
4.
Cancer Res ; 82(23): 4474-4484, 2022 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-36169924

RESUMO

Surgery is the only potentially curative treatment for localized soft-tissue sarcomas. However, for sarcomas arising in the retroperitoneum, locoregional recurrence rates are 35% to 59% despite resection. Doxorubicin (DOX) is the standard first-line systemic chemotherapy for advanced soft-tissue sarcoma, yet its intravenous administration yields limited clinical efficacy and results in dose-limiting cardiotoxicity. We report the fabrication and optimization of a novel electrospun poly(caprolactone) (PCL) surgical mesh coated with layers of a hydrophobic polymer (poly(glycerol monostearate-co-caprolactone), PGC-C18), which delivers DOX directly to the operative bed following sarcoma resection. In xenograft models of liposarcoma and chondrosarcoma, DOX-loaded meshes (DoM) increased overall survival 4-fold compared with systemically administered DOX and prevented local recurrence in all but one animal. Importantly, mice implanted with DoMs exhibited preserved cardiac function, whereas mice receiving an equivalent dose systemically displayed a 23% decrease from baseline in both cardiac output and ejection fraction 20 days after administration. Collectively, this work demonstrates a feasible therapeutic approach to simultaneously prevent post-surgical tumor recurrence and minimize cardiotoxicity in soft-tissue sarcoma. SIGNIFICANCE: A proof-of-principle study in animal models shows that a novel local drug delivery approach can prevent tumor recurrence as well as drug-related adverse events following surgical resection of soft-tissue sarcomas.


Assuntos
Sarcoma , Neoplasias de Tecidos Moles , Humanos , Camundongos , Animais , Cardiotoxicidade/etiologia , Cardiotoxicidade/prevenção & controle , Recidiva Local de Neoplasia/prevenção & controle , Doxorrubicina , Polímeros/química , Sarcoma/tratamento farmacológico , Sarcoma/cirurgia , Neoplasias de Tecidos Moles/patologia
5.
Nitric Oxide ; 125-126: 47-56, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35716999

RESUMO

RATIONALE: Nitric oxide (NO) exerts its biological effects primarily via activation of guanylate cyclase (GC) and production of cyclic guanosine monophosphate. Inhaled NO improves outcomes after cardiac arrest and cardiopulmonary resuscitation (CPR). However, mechanisms of the protective effects of breathing NO after cardiac arrest are incompletely understood. OBJECTIVE: To elucidate the mechanisms of beneficial effects of inhaled NO on outcomes after cardiac arrest. METHODS: Adult male C57BL/6J wild-type (WT) mice, GC-1 knockout mice, and chimeric WT mice with WT or GC-1 knockout bone marrow were subjected to 8 min of potassium-induced cardiac arrest to determine the role of GC-1 in bone marrow-derived cells. Mice breathed air or 40 parts per million NO for 23 h starting at 1 h after CPR. RESULTS: Breathing NO after CPR prevented hypercoagulability, cerebral microvascular occlusion, an increase in circulating polymorphonuclear neutrophils and neutrophil-to-lymphocyte ratio, and right ventricular dysfunction in WT mice, but not in GC-1 knockout mice, after cardiac arrest. The lack of GC-1 in bone marrow-derived cells diminished the beneficial effects of NO breathing after CPR. CONCLUSIONS: GC-dependent signaling in bone marrow-derived cells is essential for the beneficial effects of inhaled NO after cardiac arrest and CPR.


Assuntos
Parada Cardíaca , Óxido Nítrico , Animais , Medula Óssea , Guanilato Ciclase , Parada Cardíaca/tratamento farmacológico , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Óxido Nítrico/farmacologia , Receptores de Superfície Celular
6.
Nat Commun ; 12(1): 3108, 2021 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-34035265

RESUMO

The mammalian brain is highly vulnerable to oxygen deprivation, yet the mechanism underlying the brain's sensitivity to hypoxia is incompletely understood. Hypoxia induces accumulation of hydrogen sulfide, a gas that inhibits mitochondrial respiration. Here, we show that, in mice, rats, and naturally hypoxia-tolerant ground squirrels, the sensitivity of the brain to hypoxia is inversely related to the levels of sulfide:quinone oxidoreductase (SQOR) and the capacity to catabolize sulfide. Silencing SQOR increased the sensitivity of the brain to hypoxia, whereas neuron-specific SQOR expression prevented hypoxia-induced sulfide accumulation, bioenergetic failure, and ischemic brain injury. Excluding SQOR from mitochondria increased sensitivity to hypoxia not only in the brain but also in heart and liver. Pharmacological scavenging of sulfide maintained mitochondrial respiration in hypoxic neurons and made mice resistant to hypoxia. These results illuminate the critical role of sulfide catabolism in energy homeostasis during hypoxia and identify a therapeutic target for ischemic brain injury.


Assuntos
Lesões Encefálicas/metabolismo , Encéfalo/metabolismo , Sulfeto de Hidrogênio/metabolismo , Quinona Redutases/metabolismo , Animais , Encéfalo/patologia , Lesões Encefálicas/genética , Células Cultivadas , Feminino , Hipóxia , Masculino , Potencial da Membrana Mitocondrial , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Camundongos Knockout , Mitocôndrias/metabolismo , NAD/metabolismo , Quinona Redutases/genética , Interferência de RNA , Ratos Sprague-Dawley
7.
J Vasc Surg ; 70(4): 1308-1317, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31113720

RESUMO

OBJECTIVE: The addition of skin perfusion pressure (SPP) might enhance the predictive value of the Society for Vascular Surgery Wound, Ischemia, and foot Infection (WIfI) classification system. The purpose of the present study was to evaluate the SPP for each WIfI classification stage among patients with foot wounds by cross-referencing the results of prospectively monitored limb outcomes and to derive the SPP criteria that could be combined with other measurements to grade ischemia for the WIfI classification. METHODS: From July 2015 to June 2017, patients with foot wounds that met the WIfI classification criteria were prospectively enrolled. We assessed the limbs using the WIfI ischemia grade without measuring the transcutaneous oxygen pressure but measured the SPP. After monitoring for 1 year, the predictability of the WIfI stages was analyzed according to whether the limbs had not healed (unchanged or worsened wounds, minor or major amputation, all-cause death) or had healed (improved or healed wounds) by comparing stages 1 and 2 with stages 3 and 4. We also statistically analyzed the SPP values that could be the boundary values between each ischemia grade and reevaluated the predictability of the WIfI stages with the boundary SPP values. RESULTS: We enrolled a total of 91 limbs for 76 patients (mean age, 70.5 ± 12.0 years). The mean SPP values stratified by ischemia grade 0 to 3 were 52.1, 41.1, 27.1, and 18.8 mm Hg, respectively (an SPP of <30 mm Hg indicates severe ischemia). After monitoring for 1 year, 19 of 48 limbs in stage 1 and 2 and 35 of 43 in stage 3 and 4 were in the nonhealed group and 29 limbs in stage 1 and 2 and 8 limbs in stage 3 and 4 were in the healed group. The SPP boundary values between each ischemia (I) grade were calculated as 45 mm Hg for I-0/I-1, 35 for I-1/I-2, and 25 for I-2/I-3. When jointly using the boundary SPP values, the ischemia grade changed for 23 limbs, altering the distribution of the WIfI stages and limb outcomes: 11 of 38 limbs in stage 1 and 2 and 43 of 53 in stage 3 and 4 were transferred to the nonhealed group. The sensitivity, efficiency, and negative predictive value of WIfI staging improved when staging with SPP: from 65% to 80%, 70% to 77%, and 60% to 71%, respectively. CONCLUSIONS: The SPP boundary values that could be used with ischemia grade in the WIfI classification were identified as 45, 35, and 25 mm Hg. The addition of SPP could improve the accuracy of the evaluation.


Assuntos
Pé Diabético/diagnóstico , Pé/irrigação sanguínea , Isquemia/diagnóstico , Fluxometria por Laser-Doppler , Microcirculação , Doença Arterial Periférica/diagnóstico , Pele/irrigação sanguínea , Idoso , Idoso de 80 Anos ou mais , Amputação Cirúrgica , Velocidade do Fluxo Sanguíneo , Pé Diabético/mortalidade , Pé Diabético/fisiopatologia , Pé Diabético/terapia , Progressão da Doença , Feminino , Humanos , Isquemia/mortalidade , Isquemia/fisiopatologia , Isquemia/terapia , Japão , Salvamento de Membro , Masculino , Pessoa de Meia-Idade , Doença Arterial Periférica/mortalidade , Doença Arterial Periférica/fisiopatologia , Doença Arterial Periférica/terapia , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Fluxo Sanguíneo Regional , Medição de Risco , Fatores de Risco , Índice de Gravidade de Doença , Fatores de Tempo , Cicatrização
8.
Cell ; 177(6): 1507-1521.e16, 2019 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-31031004

RESUMO

Friedreich's ataxia (FRDA) is a devastating, multisystemic disorder caused by recessive mutations in the mitochondrial protein frataxin (FXN). FXN participates in the biosynthesis of Fe-S clusters and is considered to be essential for viability. Here we report that when grown in 1% ambient O2, FXN null yeast, human cells, and nematodes are fully viable. In human cells, hypoxia restores steady-state levels of Fe-S clusters and normalizes ATF4, NRF2, and IRP2 signaling events associated with FRDA. Cellular studies and in vitro reconstitution indicate that hypoxia acts through HIF-independent mechanisms that increase bioavailable iron as well as directly activate Fe-S synthesis. In a mouse model of FRDA, breathing 11% O2 attenuates the progression of ataxia, whereas breathing 55% O2 hastens it. Our work identifies oxygen as a key environmental variable in the pathogenesis associated with FXN depletion, with important mechanistic and therapeutic implications.


Assuntos
Hipóxia/metabolismo , Proteínas de Ligação ao Ferro/metabolismo , Proteínas Ferro-Enxofre/metabolismo , Fator 4 Ativador da Transcrição/metabolismo , Animais , Caenorhabditis elegans/metabolismo , Feminino , Ataxia de Friedreich/metabolismo , Células HEK293 , Humanos , Hipóxia/fisiopatologia , Ferro/metabolismo , Proteína 2 Reguladora do Ferro/metabolismo , Proteínas de Ligação ao Ferro/fisiologia , Proteínas Ferro-Enxofre/fisiologia , Células K562 , Masculino , Camundongos , Camundongos Knockout , Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Saccharomyces cerevisiae/metabolismo , Enxofre/metabolismo , Frataxina
9.
Mol Med Rep ; 18(2): 2467-2475, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29916549

RESUMO

Sepsis­associated encephalopathy (SAE) is a systemic inflammatory response syndrome of which the precise associated mechanisms remain unclear. Synoviolin (Syvn1) is an E3 ubiquitin ligase involved in conditions associated with chronic inflammation, including rheumatoid arthritis, obesity, fibrosis and liver cirrhosis. However, the role of Syvn1 in acute inflammation is not clear. The aim of the present study was to investigate the role of Syvn1 in a septic mouse model induced by cecal ligation/perforation (CLP). Metabolome analysis revealed that kynurenine (KYN), a key factor for the development of neuroinflammation, was increased in CLP­induced septic mice. Notably, KYN was not detected in CLP­induced septic Syvn1­deficient mice. KYN is converted to kynurenic acid (KYNA) by kynurenine aminotransferases (KATs), which has a neuroprotective effect. The expression of KAT4 was significantly increased in Syvn1­deficient mice compared to that in wild­type mice. Promoter analysis demonstrated that Syvn1 knockdown induced the KAT4 promoter activity, as assessed by luciferase reporter activity, whereas Syvn1 overexpression repressed this activity in a dose­dependent manner. Furthermore, the KAT4 promoter was significantly activated by the transcriptional factors, NF­E2­related factor 2 and peroxisome proliferator­activated receptor coactivator 1ß, which are targets of Syvn1­induced degradation. In conclusion, the results of the current study demonstrates that the repression of Syvn1 expression induces the conversion of neurotoxic KYN to neuroprotective KYNA in a CLP­induced mouse model of sepsis, and that Syvn1 is a potential novel target for the treatment of SAE.


Assuntos
Inflamação/genética , Fator 2 Relacionado a NF-E2/genética , Proteínas Nucleares/genética , Sepse/genética , Fatores de Transcrição/genética , Ubiquitina-Proteína Ligases/genética , Animais , Ceco/metabolismo , Ceco/patologia , Modelos Animais de Doenças , Humanos , Inflamação/metabolismo , Inflamação/patologia , Cinurenina/genética , Cinurenina/metabolismo , Camundongos , Sepse/metabolismo , Sepse/patologia , Transaminases/genética
10.
Biomol Ther (Seoul) ; 26(4): 399-408, 2018 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-29223141

RESUMO

In this study, we examined the molecular and functional characterization of choline uptake in the human esophageal cancer cells. In addition, we examined the influence of various drugs on the transport of [3H]choline, and explored the possible correlation between the inhibition of choline uptake and apoptotic cell death. We found that both choline transporter-like protein 1 (CTL1) and CTL2 mRNAs and proteins were highly expressed in esophageal cancer cell lines (KYSE series). CTL1 and CTL2 were located in the plasma membrane and mitochondria, respectively. Choline uptake was saturable and mediated by a single transport system, which is both Na+-independent and pH-dependent. Choline uptake and cell viability were inhibited by various cationic drugs. Furthermore, a correlation analysis of the potencies of 47 drugs for the inhibition of choline uptake and cell viability showed a strong correlation. Choline uptake inhibitors and choline deficiency each inhibited cell viability and increased caspase-3/7 activity. We conclude that extracellular choline is mainly transported via a CTL1. The functional inhibition of CTL1 by cationic drugs could promote apoptotic cell death. Furthermore, CTL2 may be involved in choline uptake in mitochondria, which is the rate-limiting step in S-adenosylmethionine (SAM) synthesis and DNA methylation. Identification of this CTL1- and CTL2-mediated choline transport system provides a potential new target for esophageal cancer therapy.

11.
Clin Case Rep ; 5(4): 508-512, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28396779

RESUMO

Therapeutic lipiodol lymphangiography for postoperative chyle leakage due to lymph duct damage has recently been attracting attention. Lymph duct puncture is technically complex and difficult. Lymphangiography and sclerotherapy can be easily applied by cannulation with a catheter for the neonatal central vein to the lymph duct under a microscope.

12.
J Pharmacol Sci ; 131(2): 101-9, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27262903

RESUMO

We examined the functional characteristics of choline uptake in human tongue carcinoma using the cell line HSC-3. Furthermore, we explored the possible correlation between the inhibition of choline uptake and apoptotic cell death. Both choline transporter-like protein 1 (CTL1) and CTL2 mRNAs and proteins were expressed, and were located in plasma membrane and mitochondria, respectively. Choline uptake was saturable and mediated by a single transport system, which is pH-dependent. Several cationic drugs inhibited cell viability and [(3)H]choline uptake. Choline uptake inhibitors and choline deficiency inhibited cell viability and increased caspase-3/7 activity. We conclude that extracellular choline is mainly transported via a CTL1 that relies on a directed H(+) gradient as a driving force. The functional inhibition of CTL1 by cationic drugs could promote apoptotic cell death. Furthermore, CTL2 may be the major site for the control of choline oxidation in mitochondria and hence for the supply of endogenous betaine and S-adenosyl methionine, which serves as a major methyl donor. Identification of this CTL1- and CTL2-mediated choline transport system provides a potential new target for tongue cancer therapy.


Assuntos
Antígenos CD/genética , Glicoproteínas de Membrana/genética , Proteínas de Membrana Transportadoras/genética , Neoplasias da Língua/metabolismo , Caspase 3/metabolismo , Caspase 7/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular , Colina/metabolismo , Humanos , RNA Mensageiro/metabolismo
13.
Stem Cells Dev ; 23(18): 2129-42, 2014 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-24325299

RESUMO

Current stem cell technologies have enabled the induction of cortical progenitors and neurons from embryonic stem cells (ESCs) and induced pluripotent stem cells in vitro. To understand the mechanisms underlying the acquisition of apico-basal polarity and the formation of processes associated with the stemness of cortical cells generated in monolayer culture, here, we developed a novel in utero transplantation system based on the moderate dissociation of adherens junctions in neuroepithelial tissue. This method enables (1) the incorporation of remarkably higher numbers of grafted cells and (2) quantitative morphological analyses at single-cell resolution, including time-lapse recording analyses. We then grafted cortical progenitors induced from mouse ESCs into the developing brain. Importantly, we revealed that the mode of process extension depends on the extrinsic apico-basal polarity of the host epithelial tissue, as well as on the intrinsic differentiation state of the grafted cells. Further, we successfully transplanted cortical progenitors induced from human ESCs, showing that our strategy enables investigation of the neurogenesis of human neural progenitors within the developing mouse cortex. Specifically, human cortical cells exhibit multiple features of radial migration. The robust transplantation method established here could be utilized both to uncover the missing gap between neurogenesis from ESCs and the tissue environment and as an in vivo model of normal and pathological human corticogenesis.


Assuntos
Polaridade Celular , Córtex Cerebral/citologia , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/transplante , Animais , Polaridade Celular/efeitos dos fármacos , Córtex Cerebral/embriologia , Córtex Cerebral/transplante , Ventrículos Cerebrais/embriologia , Ácido Egtázico/administração & dosagem , Ácido Egtázico/farmacologia , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Humanos , Camundongos Transgênicos , Neurônios/citologia , Neurônios/efeitos dos fármacos , Células-Tronco Pluripotentes/efeitos dos fármacos
14.
Masui ; 63(11): 1202-10, 2014 Nov.
Artigo em Japonês | MEDLINE | ID: mdl-25731051

RESUMO

Postoperative cognitive impairment is a recognized clinical phenomenon. Previously, such clinical findings were called "adverse cerebral effects of anesthesia on old people". POCD is transient disturbance that can affect patients of any age but is more common in elderly people. Its relevance with the immediate post-operative phase was made clear. The aging of the population and new developments in medicine both lead to the increasing number of elderly patietnts undergoing extensive surgery. Mechanism of POCD is considered to be due to the inflammatory response and Ca2+ dysregulation of the brain. For the diagnosis of POCD, pscychometric tests are applied. Risk factors for POCD are aging, extensive invasive operations, intra and postoperative complications, and anesthetics. To reduce POCD, it is necessary to provide preoperative screening and cognitive training, minimally invasive surgery, the use of short-acting agents, meticulous anesthetic technique to prevent perioperative disturbances of homeostasis and organ ischemia, tight volume balance, and EEG monitoring.


Assuntos
Transtornos Cognitivos/fisiopatologia , Complicações Pós-Operatórias/fisiopatologia , Anestesia/efeitos adversos , Cálcio/metabolismo , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/terapia , Humanos , Testes Neuropsicológicos , Complicações Pós-Operatórias/prevenção & controle , Complicações Pós-Operatórias/terapia , Fatores de Risco
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