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1.
EMBO Rep ; 24(8): e56335, 2023 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-37341560

RESUMO

While there is growing evidence that many epigenetically silenced genes in cancer are tumour suppressor candidates, their significance in cancer biology remains unclear. Here, we identify human Neuralized (NEURL), which acts as a novel tumour suppressor targeting oncogenic Wnt/ß-catenin signalling in human cancers. The expression of NEURL is epigenetically regulated and markedly suppressed in human colorectal cancer. We, therefore, considered NEURL to be a bona fide tumour suppressor in colorectal cancer and demonstrate that this tumour suppressive function depends on NEURL-mediated oncogenic ß-catenin degradation. We find that NEURL acts as an E3 ubiquitin ligase, interacting directly with oncogenic ß-catenin, and reducing its cytoplasmic levels in a GSK3ß- and ß-TrCP-independent manner, indicating that NEURL-ß-catenin interactions can lead to a disruption of the canonical Wnt/ß-catenin pathway. This study suggests that NEURL is a therapeutic target against human cancers and that it acts by regulating oncogenic Wnt/ß-catenin signalling.


Assuntos
Neoplasias do Colo , beta Catenina , Humanos , beta Catenina/genética , beta Catenina/metabolismo , Via de Sinalização Wnt , Neoplasias do Colo/genética , Ubiquitina-Proteína Ligases/metabolismo , Proteínas Contendo Repetições de beta-Transducina/genética , Proteínas Contendo Repetições de beta-Transducina/metabolismo , Linhagem Celular Tumoral
2.
Xenotransplantation ; 31(1): e12838, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38112053

RESUMO

BACKGROUND: αGal-deficient xenografts are protected from hyperacute rejection during xenotransplantation but are still rejected more rapidly than allografts. Despite studies showing the roles of non-Gal antibodies and αß T cells in xenograft rejection, the involvement of γδ T cells in xenograft rejection has been limitedly investigated. METHODS: Six male cynomolgus monkeys were transplanted with porcine vessel xenografts from wild-type (n = 3) or GGTA1 knockout (n = 3) pigs. We measured the proportions and T cell receptor (TCR) repertoires of blood γδ T cells before and after xenotransplant. Grafted porcine vessel-infiltrating immune cells were visualized at the end of experiments. RESULTS: Blood γδ T cells expanded and infiltrated into the graft vessel adventitia following xenotransplantation of α-Gal-deficient pig blood vessels. Pre- and post-transplant analysis of γδ TCR repertoire revealed a transition in δ chain usage post-transplantation, with the expansion of several clonotypes of δ1, δ3, or δ7 chains. Furthermore, the distinctions between pre- and post-transplant δ chain usages were more prominent than those observed for γ chain usages. CONCLUSION: γδ TCR repertoire was significantly altered by xenotransplantation, suggesting the role of γδ T cells in sustained xenoreactive immune responses.


Assuntos
Primatas , Subpopulações de Linfócitos T , Animais , Masculino , Xenoenxertos , Receptores de Antígenos de Linfócitos T , Suínos , Transplante Heterólogo , Macaca fascicularis
3.
Nat Mater ; 21(6): 664-672, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35301474

RESUMO

Lattice oxygen redox offers an unexplored way to access superior electrochemical properties of transition metal oxides (TMOs) for rechargeable batteries. However, the reaction is often accompanied by unfavourable structural transformations and persistent electrochemical degradation, thereby precluding the practical application of this strategy. Here we explore the close interplay between the local structural change and oxygen electrochemistry during short- and long-term battery operation for layered TMOs. The substantially distinct evolution of the oxygen-redox activity and reversibility are demonstrated to stem from the different cation-migration mechanisms during the dynamic de/intercalation process. We show that the π stabilization on the oxygen oxidation initially aids in the reversibility of the oxygen redox and is predominant in the absence of cation migrations; however, the π-interacting oxygen is gradually replaced by σ-interacting oxygen that triggers the formation of O-O dimers and structural destabilization as cycling progresses. More importantly, it is revealed that the distinct cation-migration paths available in the layered TMOs govern the conversion kinetics from π to σ interactions. These findings constitute a step forward in unravelling the correlation between the local structural evolution and the reversibility of oxygen electrochemistry and provide guidance for further development of oxygen-redox layered electrode materials.


Assuntos
Óxidos , Oxigênio , Fontes de Energia Elétrica , Eletroquímica , Oxirredução , Oxigênio/química
4.
Pancreatology ; 23(7): 878-891, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37604731

RESUMO

BACKGROUND: Intraductal papillary mucinous neoplasms (IPMNs) are a cystic precursor to pancreatic cancer. IPMNs deemed clinically to be at high-risk for malignant progression are frequently treated with surgical resection, and pathological examination of the pancreatectomy specimen is a key component of the clinical care of IPMN patients. METHODS: Systematic literature reviews were conducted around eight topics of clinical relevance in the examination of pathological specimens in patients undergoing resection of IPMN. RESULTS: This review provides updated perspectives on morphological subtyping of IPMNs, classification of intraductal oncocytic papillary neoplasms, nomenclature for high-grade dysplasia, assessment of T stage, distinction of carcinoma associated or concomitant with IPMN, role of molecular assessment of IPMN tissue, role of intraoperative assessment by frozen section, and preoperative evaluation of cyst fluid cytology. CONCLUSIONS: This analysis provides the foundation for data-driven approaches to several challenging issues in the pathology of IPMNs.


Assuntos
Adenocarcinoma Mucinoso , Carcinoma Ductal Pancreático , Neoplasias Intraductais Pancreáticas , Neoplasias Pancreáticas , Humanos , Carcinoma Ductal Pancreático/patologia , Adenocarcinoma Mucinoso/patologia , Estudos Retrospectivos , Neoplasias Pancreáticas/patologia
5.
Xenotransplantation ; 30(5): e12814, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37493436

RESUMO

Xenotransplantation using pigs' liver offers a potentially alternative method to overcome worldwide donor shortage, or more importantly as a bridge to allotransplantation. However, it has been challenged by profound thrombocytopenia and fatal coagulopathy in non-human primate models. Here we suggest that a left auxiliary technique can be a useful method to achieve extended survival of the xenograft. Fifteen consecutive liver xenotransplants were carried out in a pig-to-cynomolgus model. Right auxiliary technique was implemented in two cases, orthotopic in eight cases, and left auxiliary in five cases. None of the right auxiliary recipients survived after surgery due to hemorrhage during complex dissection between the primate's right lobe and inferior vena cava. Orthotopic recipients survived less than 7 days secondary to profound thrombocytopenia and coagulopathy. Two out of five left auxiliary xenotransplants survived more than 3 weeks without uncontrolled thrombocytopenia or anemia, with one of them surviving 34 days, the longest graft survival reported to date. Left auxiliary xenotransplant is a feasible approach in non-human primate experiments, and the feared risk of thrombocytopenia and coagulopathy can be minimized. This may allow for longer evaluation of the xenograft and help better understand histopathological and immunological changes that occur following liver xenotransplantation.


Assuntos
Transtornos da Coagulação Sanguínea , Transplante de Fígado , Trombocitopenia , Animais , Humanos , Suínos , Transplante Heterólogo/métodos , Transplante de Fígado/métodos , Rejeição de Enxerto , Animais Geneticamente Modificados , Primatas , Fígado/cirurgia , Trombocitopenia/cirurgia , Macaca fascicularis
6.
Pancreatology ; 22(3): 435-442, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35283009

RESUMO

BACKGROUND: The diagnosis of type 2 autoimmune pancreatitis (AIP) is dependent on typical radiologic imaging and the presence of the granulocytic epithelial lesion (GEL), which is characterized by ductal neutrophilic infiltration with or without neutrophilic acinar infiltration. METHODS: We evaluated GEL and related clinicopathologic factors in 165 resected heterotopic pancreata (HPs) [57 gastric (35%), 56 duodenal (34%), 30 omental (18%), and 22 jejunal (13%)] and 29 matched orthotopic pancreata routinely examined during surgery. RESULTS: GEL was noted in 8% (13/165) of HPs, including ductal epithelial (6/13, 46%) and intraluminal (8/13, 62%) neutrophilic infiltrations. However, there was no GEL in orthotopic pancreata. Abdominal pain was observed in 6 (46%) patients with GEL-positive HPs. GEL was more commonly observed in HPs having symptoms (p = 0.029), a larger size (p = 0.028), and an infiltrative growth pattern (p = 0.006). In addition, periductal lymphoplasmacytic infiltration and fibrosis (both p < 0.001), interstitial fibrosis (p = 0.017), acinar neutrophilic infiltration (p = 0.032), venulitis (p = 0.050), acinar ductal metaplasia (ADM; p = 0.040), and pancreatic intraepithelial neoplasia/intraductal papillary mucinous neoplasms (PanIN/IPMN; p < 0.001) were more commonly seen in HPs with GEL than in those without GEL. Inflammatory bowel disease was present only in one patient with GEL-negative HP. CONCLUSIONS: GELs are detected in a subset of HPs without clinical evidence of AIP. Therefore, for the diagnosis of AIP, GEL should be carefully interpreted with the context of other histologic, clinical, and radiologic findings.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Carcinoma Ductal Pancreático/patologia , Fibrose , Humanos , Pâncreas/patologia , Neoplasias Pancreáticas/patologia
7.
Pathobiology ; 89(1): 49-55, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34515187

RESUMO

BACKGROUND: Endoscopic ultrasound-guided ablation (EUS-A) therapy is a minimally invasive procedure for pancreatic-cystic tumors in patients with preoperative comorbidities or in patients who are not indicated for surgical resection. However, histopathologic characteristics of pancreatic cysts after ablation have not been well-elucidated. METHODS: Here, we analyzed pathological findings of 12 surgically resected pancreatic cysts after EUS-A with ethanol and/or paclitaxel injection. RESULTS: Mean patient age was 49.8 ± 13.6 years with a 0.3 male/female ratio. Clinical impression before EUS-A was predominantly mucinous cystic neoplasms. Mean cyst size before and after ablation therapy was similar (3.7 ± 1.0 cm vs. 3.4 ± 1.6 cm; p = 0.139). Median duration from EUS-A to surgical resection was 18 (range, 1-59) months. Mean percentage of the residual neoplastic lining epithelial cells were 23.1 ± 37.0%. Of the resected cysts, 8 cases (67%) showed no/minimal (<5%) residual lining epithelia, while the remaining 4 cases (33%) showed a wide range of residual mucinous epithelia (20-90%). Ovarian-type stroma was noted in 5 cases (42%). Other histologic features included histiocytic aggregation (67%), stromal hyalinization (67%), diffuse egg shell-like calcification along the cystic wall (58%), and fat necrosis (8%). CONCLUSION: Above all, diffuse egg shell-like calcification along the pancreatic cystic walls with residual lining epithelia and/or ovarian-type stroma were characteristics of pancreatic cysts after EUS-A. Therefore, understanding these histologic features will be helpful for precise pathological diagnosis of pancreatic cystic tumor after EUS-A, even without knowing the patient's history of EUS-A.


Assuntos
Cisto Pancreático , Neoplasias Pancreáticas , Pseudocisto Pancreático , Adulto , Endossonografia , Etanol , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Paclitaxel , Cisto Pancreático/diagnóstico por imagem , Cisto Pancreático/cirurgia , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/tratamento farmacológico
8.
Chem Rev ; 120(14): 6684-6737, 2020 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-31793294

RESUMO

The electrochemical properties and performances of lithium-ion batteries are primarily governed by their constituent electrode materials, whose intrinsic thermodynamic and kinetic properties are understood as the determining factor. As a part of complementing the intrinsic material properties, the strategy of nanosizing has been widely applied to electrodes to improve battery performance. It has been revealed that this not only improves the kinetics of the electrode materials but is also capable of regulating their thermodynamic properties, taking advantage of nanoscale phenomena regarding the changes in redox potential, solid-state solubility of the intercalation compounds, and reaction paths. In addition, the nanosizing of materials has recently enabled the discovery of new energy storage mechanisms, through which unexplored classes of electrodes could be introduced. Herein, we review the nanoscale phenomena discovered or exploited in lithium-ion battery chemistry thus far and discuss their potential implications, providing opportunities to further unveil uncharted electrode materials and chemistries. Finally, we discuss the limitations of the nanoscale phenomena presently employed in battery applications and suggest strategies to overcome these limitations.

9.
Nat Mater ; 19(4): 419-427, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31959949

RESUMO

Despite the high energy density of lithium-rich layered-oxide electrodes, their real-world implementation in batteries is hindered by the substantial voltage decay on cycling. This voltage decay is widely accepted to mainly originate from progressive structural rearrangements involving irreversible transition-metal migration. As prevention of this spontaneous cation migration has proven difficult, a paradigm shift toward management of its reversibility is needed. Herein, we demonstrate that the reversibility of the cation migration of lithium-rich nickel manganese oxides can be remarkably improved by altering the oxygen stacking sequences in the layered structure and thereby dramatically reducing the voltage decay. The preeminent intra-cycle reversibility of the cation migration is experimentally visualized, and first-principles calculations reveal that an O2-type structure restricts the movements of transition metals within the Li layer, which effectively streamlines the returning migration path of the transition metals. Furthermore, we propose that the enhanced reversibility mitigates the asymmetry of the anionic redox in conventional lithium-rich electrodes, promoting the high-potential anionic reduction, thereby reducing the subsequent voltage hysteresis. Our findings demonstrate that regulating the reversibility of the cation migration is a practical strategy to reduce voltage decay and hysteresis in lithium-rich layered materials.

10.
Phys Chem Chem Phys ; 23(14): 8607-8617, 2021 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-33876022

RESUMO

The electrochemical charge storage of sodium vanadate (NaV3O8 or NVO) cathodes in aqueous Zn-ion batteries has been hypothesized to be influenced by the inclusion of structural water for facilitating ion transfer in the material. Materials properties considered important (morphology, crystallite and particle size, surface area) are systematically studied herein through investigation of two NVO materials, NaV3O8·0.34H2O [NVO(300)] and NaV3O8·0.05H2O [NVO(500)], with different water content, acicular morphologies with different size and surface area achieved via post-synthesis heat treatment. The electrochemistry of the two materials was evaluated in aqueous Zn-ion cells with 2 M ZnSO4 electrolyte using cyclic voltammetry, galvanostatic cycling, and rate capability testing. The thinner NVO(300) nanobelts (0.13 µm) demonstrate greater specific capacities and higher effective diffusion coefficients relative to the thicker NVO(500) nanorods. Notably however, while cells containing NVO(500) deliver lower specific capacity, they demonstrate enhanced capacity retention with cycling. The structural changes accompanying oxidation and reduction are elucidated via ex situ X-ray diffraction, transmission electron microscopy, and operando V K-edge X-ray absorption spectroscopy (XAS), where NVO material properties are shown to influence the ion insertion. Operando XAS verified that electron transfer corresponds directly to change in vanadium oxidation state, affirming vanadium redox as the governing electrochemical process.

11.
HPB (Oxford) ; 23(2): 220-230, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32654914

RESUMO

BACKGROUND: Solid pseudopapillary neoplasms (SPNs) of the pancreas have low malignant potential. However, malignant SPNs are not fully understood. METHODS: To evaluate risk factors affecting malignant potential, the clinicopathologic features of 375 surgically resected SPNs were compared. RESULTS: Fifty (13.3%) had malignant histologic features. Twenty-seven and 22 had perineural and lymphovascular invasions, respectively. Adjacent organ invasion was noted in 9 cases. Recurrence occurred in 8 cases. The median recurrence time after surgical resection was 67 months and was associated with a higher pT category (P = 0.001), lymphovascular invasion (P < 0.001), and synchronous metastasis (P < 0.001). SPN patients with malignant histologic features had worse recurrence-free survival (RFS; 10-year survival rate, 73.2%) than those without malignant histologic features (96.3%; P = 0.01). Patients with a higher pT category (P = 0.04), synchronous metastasis (P < 0.01), and lymphovascular invasion (P < 0.01) had worse RFS. Lymphovascular invasion (P = 0.042) and a higher T category (P = 0.002) were poor prognostic factors for recurrence. CONCLUSION: Lymphovascular invasion and a higher T category were worse prognostic factors for recurrence in SPN patients with malignant histologic features. For SPN patients with malignant histologic features, a longer follow-up may be required.


Assuntos
Carcinoma Papilar , Neoplasias Pancreáticas , Carcinoma Papilar/cirurgia , Humanos , Recidiva Local de Neoplasia , Pâncreas , Pancreatectomia/efeitos adversos , Neoplasias Pancreáticas/cirurgia , Prognóstico , Estudos Retrospectivos
12.
Clin Infect Dis ; 70(2): 181-190, 2020 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-30843046

RESUMO

BACKGROUND: The incidence of herpes zoster is up to 9 times higher in immunosuppressed solid organ transplant recipients than in the general population. We investigated the immunogenicity and safety of an adjuvanted recombinant zoster vaccine (RZV) in renal transplant (RT) recipients ≥18 years of age receiving daily immunosuppressive therapy. METHODS: In this phase 3, randomized (1:1), observer-blind, multicenter trial, RT recipients were enrolled and received 2 doses of RZV or placebo 1-2 months (M) apart 4-18M posttransplant. Anti-glycoprotein E (gE) antibody concentrations, gE-specific CD4 T-cell frequencies, and vaccine response rates were assessed at 1M post-dose 1, and 1M and 12M post-dose 2. Solicited and unsolicited adverse events (AEs) were recorded for 7 and 30 days after each dose, respectively. Solicited general symptoms and unsolicited AEs were also collected 7 days before first vaccination. Serious AEs (including biopsy-proven allograft rejections) and potential immune-mediated diseases (pIMDs) were recorded up to 12M post-dose 2. RESULTS: Two hundred sixty-four participants (RZV: 132; placebo: 132) were enrolled between March 2014 and April 2017. gE-specific humoral and cell-mediated immune responses were higher in RZV than placebo recipients across postvaccination time points and persisted above prevaccination baseline 12M post-dose 2. Local AEs were reported more frequently by RZV than placebo recipients. Overall occurrences of renal function changes, rejections, unsolicited AEs, serious AEs, and pIMDs were similar between groups. CONCLUSIONS: RZV was immunogenic in chronically immunosuppressed RT recipients. Immunogenicity persisted through 12M postvaccination. No safety concerns arose. CLINICAL TRIALS REGISTRATION: NCT02058589.


Assuntos
Vacina contra Herpes Zoster , Herpes Zoster , Imunogenicidade da Vacina , Transplante de Rim , Adulto , Anticorpos Antivirais , Herpes Zoster/prevenção & controle , Herpesvirus Humano 3 , Humanos , Vacinas Sintéticas/efeitos adversos
13.
Small ; 16(48): e2005406, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33166057

RESUMO

Aqueous Zn/α-MnO2 batteries have attracted immense interest owing to their high energy density, low cost, and safety, making them desirable for future large-scale energy application. Despite these merits, the comprehensive understanding of their reaction mechanism has been elusive due to the limitations of standard bulk characterization. Here, via transmission electron microscopy, the dissolution-mediated reaction mechanism of a Zn/α-MnO2 system is discovered and explored in full scope to involve reversible formation of Zn4 SO4 (OH)6 ·xH2 O and "birnessite-like" Zn-MnOx phase upon cycling. Overall, α-MnO2 acts primarily as a source for cell activation through dissolution and thus is not directly involved in the Zn redox chemistry. This microscopic study offers a unique knowledge on the unconventional reaction chemistry of Zn/α-MnO2 batteries.

14.
Pancreatology ; 20(7): 1486-1494, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32948429

RESUMO

OBJECTIVES: Venous invasion is a poor prognostic factor for pancreatic ductal adenocarcinoma (PDAC). However, our understanding of various features of venous invasion is limited. Our aim is to comprehensively evaluate various histopathologic features of venous invasion, including status, type (lymphatic or venous), number of invasion foci, and histologic pattern (pancreatic intraepithelial neoplasia [PanIN]-like, conventional) in PDACs. METHODS: Various features of venous invasion, including status, number of invasion foci, histologic patterns [pancreatic intraepithelial neoplasia (PanIN)-like, conventional], and size of involved vessels in 471 surgically resected PDACs were evaluated with all available hematoxylin and eosin (H&E)-stained slides. RESULTS: Venous invasion was observed in 319 cases (67.7%) and was more frequently associated with increased tumor size, extrapancreatic extension, resection margin involvement, diffuse tumor distribution, lymph node metastasis, and perineural invasion (all Ps < .05). High frequency (≥3 foci) of venous invasion was associated with shorter overall survival both in the entire group and in the early stage subgroup (stage I; all Ps < .05). Multivariate analysis indicated that a high frequency (≥3 foci) of venous invasion, large tumor size (>4 cm), higher histologic grade, and lymph node metastasis, were independent prognostic factors of worse overall survival (all Ps < .05). CONCLUSION: Precise evaluation of venous invasion status, including foci number of invasion, can provide additional prognostic information for patients undergoing surgical resection of PDAC, especially for those with early disease stage.


Assuntos
Carcinoma Ductal Pancreático/irrigação sanguínea , Carcinoma Ductal Pancreático/patologia , Neoplasias Pancreáticas/irrigação sanguínea , Neoplasias Pancreáticas/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Ductal Pancreático/cirurgia , Feminino , Humanos , Estimativa de Kaplan-Meier , Metástase Linfática/patologia , Masculino , Margens de Excisão , Pessoa de Meia-Idade , Invasividade Neoplásica/patologia , Metástase Neoplásica , Estadiamento de Neoplasias , Neoplasias Pancreáticas/cirurgia , Prognóstico , Fluxo Sanguíneo Regional , Análise de Sobrevida , Veias/patologia
15.
BMC Nephrol ; 21(1): 3, 2020 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-31902366

RESUMO

PURPOSE: Dual kidney transplantation (DKT) offers a way to extend the use of kidneys from expanded criteria donors (ECDs). Here, we compared the outcomes of DKT with those of single kidney transplantation from standard criteria donors (SCDs) and ECDs. METHODS: In 2014, we began performing DKT using both kidneys from deceased donors greater than 70 years of age with one of two risk factors: serum creatinine (sCr) level over 3.0 mg/dl or eGFR under 30 ml/min. By 2017, we had performed 15 DKTs. We compared the outcomes of the 15 DKT recipients with those of 124 patients who received a kidney from an SCD and 80 patients who received a kidney from an ECD. RESULTS: Compared with ECDs and SCDs, DKT donors were older, had a higher diabetes burden, and a higher sCr level (p < 0.01, < 0.01, and 0.03, respectively). DKT recipients were also older and had a higher diabetes burden than recipients of kidneys from ECDs and SCDs (p < 0.01, both). DKT recipients had a lower nadir sCr and shorter duration to nadir sCr than single ECD KT recipients (p < 0.01and 0.04, respectively). CONCLUSIONS: The survival rates of DKT grafts were compatible with those of single KT grafts. Therefore, DKT may be considered a suitable an option to expand the donor pool.


Assuntos
Transplante de Rim , Doadores de Tecidos , Adulto , Idoso , Cadáver , Creatinina/sangue , Diabetes Mellitus , Feminino , Taxa de Filtração Glomerular , Sobrevivência de Enxerto , Humanos , Transplante de Rim/métodos , Masculino , Pessoa de Meia-Idade , Análise de Sobrevida
16.
Angew Chem Int Ed Engl ; 59(13): 5376-5380, 2020 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-31953979

RESUMO

Redox mediators (RMs) are considered an effective countermeasure to reduce the large polarization in lithium-oxygen batteries. Nevertheless, achieving sufficient enhancement of the cyclability is limited by the trade-offs of freely mobile RMs, which are beneficial for charge transport but also trigger the shuttling phenomenon. Here, we successfully decoupled the charge-carrying redox property of RMs and shuttling phenomenon by anchoring the RMs in polymer form, where physical RM migration was replaced by charge transfer along polymer chains. Using PTMA (poly(2,2,6,6-tetramethyl-1-piperidinyloxy-4-yl methacrylate)) as a polymer model system based on the well-known RM tetramethylpiperidinyloxyl (TEMPO), it is demonstrated that PTMA can function as stationary RM, preserving the redox activity of TEMPO. The efficiency of RM-mediated Li2 O2 decomposition remains remarkably stable without the consumption of oxidized RMs or degradation of the lithium anode, resulting in an improved performance of the lithium-oxygen cell.

17.
J Hepatol ; 70(1): 97-107, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30240598

RESUMO

BACKGROUND & AIMS: Currently, much effort is directed towards the development of new cell sources for clinical therapy using cell fate conversion by small molecules. Direct lineage reprogramming to a progenitor state has been reported in terminally differentiated rodent hepatocytes, yet remains a challenge in human hepatocytes. METHODS: Human hepatocytes were isolated from healthy and diseased donor livers and reprogrammed into progenitor cells by 2 small molecules, A83-01 and CHIR99021 (AC), in the presence of EGF and HGF. The stemness properties of human chemically derived hepatic progenitors (hCdHs) were tested by standard in vitro and in vivo assays and transcriptome profiling. RESULTS: We developed a robust culture system for generating hCdHs with therapeutic potential. The use of HGF proved to be an essential determinant of the fate conversion process. Based on functional evidence, activation of the HGF/MET signal transduction system collaborated with A83-01 and CHIR99021 to allow a rapid expansion of progenitor cells through the activation of the ERK pathway. hCdHs expressed hepatic progenitor markers and could self-renew for at least 10 passages while retaining a normal karyotype and potential to differentiate into functional hepatocytes and biliary epithelial cells in vitro. Gene expression profiling using RNAseq confirmed the transcriptional reprogramming of hCdHs towards a progenitor state and the suppression of mature hepatocyte transcripts. Upon intrasplenic transplantation in several models of therapeutic liver repopulation, hCdHs effectively repopulated the damaged parenchyma. CONCLUSION: Our study is the first report of successful reprogramming of human hepatocytes to a population of proliferating bipotent cells with regenerative potential. hCdHs may provide a novel tool that permits expansion and genetic manipulation of patient-specific progenitors to study regeneration and the repair of diseased livers. LAY SUMMARY: Human primary hepatocytes were reprogrammed towards hepatic progenitor cells by a combined treatment with 2 small molecules, A83-01 and CHIR99021, and HGF. Chemically derived hepatic progenitors exhibited a high proliferation potential and the ability to differentiate into hepatocytes and biliary epithelial cells both in vitro and in vivo. This approach enables the generation of patient-specific hepatic progenitors and provides a platform for personal and stem cell-based regenerative medicine.


Assuntos
Hepatócitos/citologia , Regeneração Hepática , Fígado/citologia , Células-Tronco/citologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Feminino , Quinase 3 da Glicogênio Sintase , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Pessoa de Meia-Idade , Modelos Animais , Pirazóis/farmacologia , Piridinas/farmacologia , Pirimidinas/farmacologia , Células-Tronco/efeitos dos fármacos , Células-Tronco/metabolismo , Tiossemicarbazonas/farmacologia
18.
Am J Pathol ; 188(7): 1530-1535, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29684363

RESUMO

Visualizing pathologies in three dimensions can provide unique insights into the biology of human diseases. A rapid and easy-to-implement dibenzyl ether-based technique was used to clear thick sections of surgically resected human pancreatic parenchyma. Protocols were applicable to both fresh and formalin-fixed, paraffin-embedded tissue. The penetration of antibodies into dense pancreatic parenchyma was optimized using both gradually increasing antibody concentrations and centrifugal flow. Immunolabeling with antibodies against cytokeratin 19 was visualized using both light sheet and confocal laser scanning microscopy. The technique was applied successfully to 26 sections of pancreas, providing three-dimensional (3D) images of normal pancreatic tissue, pancreatic intraepithelial neoplasia, intraductal papillary mucinous neoplasms, and infiltrating pancreatic ductal adenocarcinomas. 3D visualization highlighted processes that are hard to conceptualize in two dimensions, such as invasive carcinoma growing into what appeared to be pre-existing pancreatic ducts and within venules, and the tracking of long cords of neoplastic cells parallel to blood vessels. Expanding this technique to formalin-fixed, paraffin-embedded tissue opens pathology archives to 3D visualization of unique biosamples and rare diseases. The application of immunolabeling and clearing to human pancreatic parenchyma provides detailed visualization of normal pancreatic anatomy, and can be used to characterize the 3D architecture of diseases including pancreatic intraepithelial neoplasia, intraductal papillary mucinous neoplasm, and pancreatic ductal adenocarcinomas.


Assuntos
Adenocarcinoma Mucinoso/patologia , Carcinoma Ductal Pancreático/patologia , Imageamento Tridimensional/métodos , Pâncreas/anatomia & histologia , Neoplasias Pancreáticas/patologia , Coloração e Rotulagem/métodos , Adenocarcinoma Mucinoso/metabolismo , Carcinoma Ductal Pancreático/metabolismo , Humanos , Imuno-Histoquímica , Microscopia Confocal , Pâncreas/metabolismo , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas
19.
Histopathology ; 75(4): 559-567, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31077597

RESUMO

AIMS: Mucinous cystic neoplasms (MCNs) of the pancreas are cystic neoplasms lined by mucinous lining epithelium (MLE) with associated ovarian-type stroma. Although a non-MLE (NMLE) can be observed in some MCNs, whether cystic neoplasms with ovarian-type stroma and NMLE should be classified as MCNs or separately designated is debated. METHODS AND RESULTS: To test this, NMLEs were defined as flat or cuboidal epithelial cells without intracytoplasmic mucin. A total of 112 MCNs were reviewed, and the epithelium was classified as NMLE or MLE. A total of 110 females and two males with a mean age of 46.5 ± 12.3 years were included in this study. At least focal NMLE was noted in 76.8% (86/112) of MCNs. The mean percentage of the neoplastic epithelium that was NMLE in these 86 cases was 46%. NMLE was predominant (>50%) in 38.4% (43/112) of cases. MCNs with NMLE were smaller (42 ± 21 mm) than those with MLE (60 ± 36 mm, P < 0.001), and all NMLEs had low-grade dysplasia. Twelve MCNs with NMLE or MLE were selected for KRAS mutation analysis with droplet digital polymerase chain reaction after laser capture microdissection. All 12 MCNs showed multiple types of KRAS mutation, which were detected in 92% (11/12) of NMLE foci and 89% (8/9) of MLE foci. Predominant NMLE was common in small MCNs with low-grade dysplasia. CONCLUSIONS: Clonal KRAS mutations were observed in both NMLE and MLE, supporting the hypothesis that MCNs with NMLE should be classified as MCNs.


Assuntos
Cistadenocarcinoma Mucinoso/patologia , Neoplasias Pancreáticas/patologia , Proteínas Proto-Oncogênicas p21(ras)/genética , Adulto , Cistadenocarcinoma Mucinoso/genética , Epitélio/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Neoplasias Pancreáticas/genética
20.
BMC Cancer ; 19(1): 496, 2019 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-31126284

RESUMO

BACKGROUND: Liposarcoma (LPS) is a tumor derived from adipose tissue, and has the highest incidence among soft tissue sarcomas. Dedifferentiated liposarcoma (DDLPS) is a malignant tumor with poor prognosis. Recurrence and metastasis rates in LPS remain high even after chemotherapy and radiotherapy following complete resection. Therefore, the development of advanced treatment strategies for LPS is required. In the present study, we investigated the effect of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) treatment, and of combination treatment using TRAIL and a c-Met inhibitor on cell viability and apoptosis in LPS and DDLPS cell lines of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) treatment, and of combination treatment using TRAIL and a c-Met inhibitor. METHODS: We analyzed cell viability after treatment with TRAIL and a c-Met inhibitor by measuring CCK8 and death receptor 5 (DR5) expression levels via fluorescence activated cell sorting (FACS) in both sarcoma cell lines and DDLPS patient-derived cells (PDCs). Moreover, we validated the effects of TRAIL alone and in combination with c-Met inhibitor on apoptosis in LPS cell lines and DDLPS PDCs via FACS. RESULTS: Our results revealed that combination treatment with a c-Met inhibitor and human recombinant TRAIL (rhTRAIL) suppressed cell viability and induced cell death in both sarcoma cell lines and DDLPS PDCs, which showed varying sensitivities to rhTRAIL alone. Also, we confirmed that treatment with a c-Met inhibitor upregulated DR5 levels in sarcoma cell lines and DDLPS PDCs. In both TRAIL-susceptible and TRAIL-resistant cells subjected to combination treatment, promotion of apoptosis was dependent on DR5 upregulation. CONCLUSION: From these results, our findings validated that DR5 up-regulation caused by combination therapy with a c-Met inhibitor and rhTRAIL enhanced TRAIL sensitization and promoted apoptosis. We propose the use of this approach to overcome TRAIL resistance and serve as a novel treatment strategy for clinical trials.


Assuntos
Crizotinibe/farmacologia , Crizotinibe/uso terapêutico , Lipossarcoma/tratamento farmacológico , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Proteínas Recombinantes/uso terapêutico , Ligante Indutor de Apoptose Relacionado a TNF/uso terapêutico , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Sinergismo Farmacológico , Quimioterapia Combinada , Citometria de Fluxo , Humanos , Lipossarcoma/patologia , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/metabolismo
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