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1.
Nat Mater ; 22(8): 992-998, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37365226

RESUMO

Conventional antiferroelectric materials with atomic-scale anti-aligned dipoles undergo a transition to a ferroelectric (FE) phase under strong electric fields. The moiré superlattice formed in the twisted stacks of van der Waals crystals exhibits polar domains alternating in moiré length with anti-aligned dipoles. In this moiré domain antiferroelectic (MDAF) arrangement, the distribution of electric dipoles is distinguished from that of two-dimensional FEs, suggesting dissimilar domain dynamics. Here we performed an operando transmission electron microscopy investigation on twisted bilayer WSe2 to observe the polar domain dynamics in real time. We find that the topological protection, provided by the domain wall network, prevents the MDAF-to-FE transition. As one decreases the twist angle, however, this transition occurs as the domain wall network disappears. Exploiting stroboscopic operando transmission electron microscopy on the FE phase, we measure a maximum domain wall velocity of 300 µm s-1. Domain wall pinnings by various disorders limit the domain wall velocity and cause Barkhausen noises in the polarization hysteresis loop. Atomic-scale analysis of the pinning disorders provides structural insight on how to improve the switching speed of van der Waals FEs.

2.
Ecotoxicol Environ Saf ; 280: 116544, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38838463

RESUMO

Benzyl butyl phthalate (BBP) is a widely used plasticizer that poses various potential health hazards. Although BBP has been extensively studied, the direct mechanism underlying its toxicity in male germ cells remains unclear. Therefore, we investigated BBP-mediated male germ cell toxicity in GC-1 spermatogonia (spg), a differentiated mouse male germ cell line. This study investigated the impact of BBP on reactive oxygen species (ROS) generation, apoptosis, and autophagy regulation, as well as potential protective measures against BBP-induced toxicity. A marked dose-dependent decrease in GC-1 spg cell proliferation was observed following treatment with BBP at 12.5 µM. Exposure to 50 µM BBP, approximating the IC50 of 53.9 µM, markedly increased cellular ROS generation and instigated apoptosis, as evidenced by augmented protein levels of both intrinsic and extrinsic apoptosis-related markers. An amount of 50 µM BBP induced marked upregulation of autophagy regulator proteins, p38 MAPK, and extracellular signal-regulated kinase and substantially downregulated the phosphorylation of key kinases involved in regulating cell proliferation, including phosphoinositide 3-kinase, protein kinase B, mammalian target of rapamycin (mTOR), c-Jun N-terminal kinase. The triple combination of N-acetylcysteine, parthenolide, and 3-methyladenine markedly restored cell proliferation, decreased BBP-induced apoptosis and autophagy, and restored mTOR phosphorylation. This study provides new insights into BBP-induced male germ cell toxicity and highlights the therapeutic potential of the triple inhibitors in mitigating BBP toxicity.


Assuntos
Acetilcisteína , Adenina , Apoptose , Autofagia , Proliferação de Células , Ácidos Ftálicos , Espécies Reativas de Oxigênio , Sesquiterpenos , Masculino , Animais , Camundongos , Ácidos Ftálicos/toxicidade , Autofagia/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Sesquiterpenos/farmacologia , Acetilcisteína/farmacologia , Adenina/análogos & derivados , Adenina/farmacologia , Adenina/toxicidade , Proliferação de Células/efeitos dos fármacos , Linhagem Celular , Plastificantes/toxicidade , Espermatogônias/efeitos dos fármacos
3.
Breast Cancer Res ; 25(1): 4, 2023 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-36635767

RESUMO

BACKGROUND: Cyclin-dependent kinase 4 and 6 (CDK4/6) inhibitors have been established as a standard treatment for hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative advanced breast cancer (ABC); however, predictive biomarkers with translational relevance have not yet been elucidated. METHODS: Data from postmenopausal women who received the CDK4/6 inhibitor palbociclib and letrozole for HR-positive, HER2-negative ABC from tertiary referral centers were analyzed (N = 221; exploratory cohort). Pre- and on-treatment neutrophil-to-lymphocyte ratio (NLR) and derived NLR (dNLR; neutrophil/[leukocyte-neutrophil]) were correlated with survival outcomes. Data from the PALOMA-2 (NCT01740427) and PALOMA-3 studies (NCT01942135) involving patients treated with endocrine treatment with or without palbociclib were also analyzed (validation cohort). Prospectively enrolled patients (N = 20) were subjected to immunophenotyping with circulating immune cells to explore the biological implications of immune cell dynamics. RESULTS: In the exploratory cohort, palbociclib administration significantly reduced leukocyte, neutrophil, and lymphocyte counts on day 1 of cycle 2. Although the baseline dNLR was not significantly associated with progression-free survival (PFS), higher on-treatment dNLRs were associated with worse PFS (hazard ratio = 3.337, P < 0.001). In the PALOMA-2 validation cohort, higher on-treatment dNLRs were associated with inferior PFS in patients treated with palbociclib and letrozole (hazard ratio = 1.498, P = 0.009), and reduction in the dNLR after treatment was predictive of a survival benefit (hazard ratio = 1.555, P = 0.026). On-treatment dNLRs were also predictive of PFS following palbociclib and fulvestrant treatment in the PALOMA-3 validation cohort. Using flow cytometry analysis, we found that the CDK4/6 inhibitor prevented T cell exhaustion and diminished myeloid-derived suppressor cell frequency. CONCLUSIONS: On-treatment dNLR significantly predicted PFS in patients with HR-positive, HER2-negative ABC receiving palbociclib and endocrine treatment. Additionally, we observed putative systemic immune responses elicited by palbociclib, suggesting immunologic changes upon CDK4/6 inhibitor treatment.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Letrozol/uso terapêutico , Neoplasias da Mama/metabolismo , Neutrófilos/metabolismo , Estudos Retrospectivos , Receptor ErbB-2/metabolismo , Linfócitos/metabolismo , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos
4.
Arthroscopy ; 2023 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-37890542

RESUMO

PURPOSE: To assess the effects of intravenous tranexamic acid (TXA) on visual clarity at various surgical stages and the correlation between the severity of synovitis and bursitis and the grade of visual clarity in patients undergoing arthroscopic shoulder surgery under an interscalene brachial plexus block. METHODS: This double-blind, randomized controlled study included patients undergoing arthroscopic rotator cuff repair. The TXA group underwent injection of a 100-mL mixture of 1,000 mg of TXA and normal saline solution intravenously whereas the control group was administered the same volume of normal saline solution at 10 minutes preoperatively. Visual clarity was rated according to a 3-grade visual clarity scoring system from grade 1 (clear) to grade 3 (poor) at 4 surgical stages (I, intra-articular soft-tissue procedures including synovectomy; II, acromioplasty; III, bursectomy; and IV, greater tuberoplasty). The primary outcome was arthroscopic visual clarity. The secondary outcomes were medications administered for hemodynamic stability, length of hospital stay, and thromboembolic events. RESULTS: Altogether, 63 patients were included in the study; they were divided into the TXA group, comprising 32 patients, and the control group, comprising 31 patients. The TXA group showed significantly better visual clarity than the control group (median [interquartile range], 1 [1-2] vs 2 [1-2]; P = .027) during stage I but not during stages II through IV. Spearman correlation analysis revealed a significant correlation between synovitis and visual clarity grade during synovectomy (correlation coefficient, 0.393; P = .001) but not between bursitis and visual clarity grade during bursectomy. Deep vein thrombosis and pulmonary embolism did not occur in either group. CONCLUSIONS: Intravenous TXA can improve visual clarity during intra-articular soft-tissue procedures, including synovectomy. However, it does not have a significant effect during acromioplasty, bursectomy, and greater tuberoplasty. TXA can be used to improve visual clarity in patients with suspected severe synovitis. LEVEL OF EVIDENCE: Level I, randomized controlled trial.

5.
BMC Med Inform Decis Mak ; 23(1): 3, 2023 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-36609301

RESUMO

BACKGROUND: To validate a stratification method using an inverse of treatment decision rules that can classify non-small cell lung cancer (NSCLC) patients in real-world treatment records. METHODS: (1) To validate the index classifier against the TNM 7th edition, we analyzed electronic health records of NSCLC patients diagnosed from 2011 to 2015 in a tertiary referral hospital in Seoul, Korea. Predictive accuracy, stage-specific sensitivity, specificity, positive predictive value, negative predictive value, F1 score, and c-statistic were measured. (2) To apply the index classifier in an administrative database, we analyzed NSCLC patients in Korean National Health Insurance Database, 2002-2013. Differential survival rates among the classes were examined with the log-rank test, and class-specific survival rates were compared with the reference survival rates. RESULTS: (1) In the validation study (N = 1375), the overall accuracy was 93.8% (95% CI: 92.5-95.0%). Stage-specific c-statistic was the highest for stage I (0.97, 95% CI: 0.96-0.98) and the lowest for stage III (0.82, 95% CI: 0.77-0.87). (2) In the application study (N = 71,593), the index classifier showed a tendency for differentiating survival probabilities among classes. Compared to the reference TNM survival rates, the index classification under-estimated the survival probability for stages IA, IIIB, and IV, and over-estimated it for stages IIA and IIB. CONCLUSION: The inverse of the treatment decision rules has a potential to supplement a routinely collected database with information encoded in the treatment decision rules to classify NSCLC patients. It requires further validation and replication in multiple clinical settings.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/terapia , Prognóstico , Estadiamento de Neoplasias , Registros Eletrônicos de Saúde , Estudos Retrospectivos
6.
Int J Mol Sci ; 24(23)2023 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-38069409

RESUMO

Poly (ADP-ribose) polymerase (PARP) inhibitors are effective against BRCA1/2-mutated cancers through synthetic lethality. Unfortunately, most cases ultimately develop acquired resistance. Therefore, enhancing PARP inhibitor sensitivity and preventing resistance in those cells are an unmet clinical need. Here, we investigated the ability of paraspeckle component 1 (PSPC1), as an additional synthetic lethal partner with BRCA1/2, to enhance olaparib sensitivity in preclinical models of BRCA1/2-mutated breast and ovarian cancers. In vitro, the combined olaparib and PSPC1 small interfering RNA (siRNA) exhibited synergistic anti-proliferative activity in BRCA1/2-mutated breast and ovarian cancer cells. The combination therapy also demonstrated synergistic tumor inhibition in a xenograft mouse model. Mechanistically, olaparib monotherapy increased the expressions of p-ATM and DNA-PKcs, suggesting the activation of a DNA repair pathway, whereas combining PSPC1 siRNA with olaparib decreased the expressions of p-ATM and DNA-PKcs again. As such, the combination increased the formation of γH2AX foci, indicating stronger DNA double-strand breaks. Subsequently, these DNA-damaged cells escaped G2/M checkpoint activation, as indicated by the suppression of p-cdc25C (Ser216) and p-cdc2 (Tyr15) after combination treatment. Finally, these cells entered mitosis, which induced increased apoptosis. Thus, this proves that PSPC1 inhibition enhances olaparib sensitivity by targeting DNA damage response in our preclinical model. The combination of olaparib and PSPC1 inhibition merits further clinical investigation to enhance PARP inhibitor efficacy.


Assuntos
Antineoplásicos , Neoplasias da Mama , Neoplasias Ovarianas , Inibidores de Poli(ADP-Ribose) Polimerases , Animais , Antineoplásicos/uso terapêutico , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Neoplasias Ovarianas/tratamento farmacológico , Humanos , Feminino , Camundongos , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Proteínas de Ligação a RNA/antagonistas & inibidores , Proteína BRCA1/genética , Proteína BRCA2/genética , RNA Interferente Pequeno/genética
7.
Anal Chem ; 93(24): 8638-8646, 2021 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-34110775

RESUMO

In situ wireless monitoring for cell proliferation and detachment kinetics was conducted using pH-responsive zwitterionic polymer dots (Z-PDs), based on changes in electrochemical signals derived from Z-PD-coated substrates via the interaction of charges transferred between Z-PDs and cells. Z-PD-coated substrates were found to be a potent means to monitor and manipulate cell adhesion and detachment because of their high sensitivity over a wide range of pH conditions, and modification of the coated substrates was confirmed using a wireless system. At neutral pH, Z-PD-coated wireless sensors exhibited π-π stacking involving aromatic rings with hydrophobic interactions, thereby promoting cell proliferation; consequently, an increase in the measured resistance was observed. In contrast, Z-PD-coated substrates triggered by acidic and basic conditions promoted cell detachment, which induced an increase in the resistance compared with Z-PD substrates at pH 6.8, as a result of charges transferred to support Z-PD internalization through cell membranes after detachment. Therefore, as a wireless biosensor with excellent pH responsiveness that facilitates cell proliferation and detachment and whose electrochemical signals could be additionally acquired via a smartphone, Z-PD biosensors demonstrated a more favorable approach for monitoring cell-surface interactions than conventional optically based methods.


Assuntos
Polímeros , Proliferação de Células , Condutividade Elétrica , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas
8.
J Labelled Comp Radiopharm ; 64(1): 4-13, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33037721

RESUMO

The objective of this study was to report the synthesis and characteristics of a dual modality imaging agent, Tc-99m GRFLTGGTGRLLRIS-GHEG-ECG-K(-5-carboxy-X-rhodamine)-NH2 (GRFLT-ECG-ROX), and to verify its feasibility as both molecular imaging and intraoperative guidance agent. GRFLT-ECG-ROX was synthesized using Fmoc solid-phase peptide synthesis. Radiolabeling of GRFLT-ECG-ROX with Tc-99m was accomplished using ligand exchange via tartrate. Binding affinity and in vitro cellular uptake studies were performed. Gamma camera imaging, biodistribution, and ex vivo imaging studies were performed using LNCaP and PC-3 tumor-bearing murine models. Surgical removal of tumor nodules in murine models with peritoneal carcinomatosis was performed under a fluorescence imaging system. After radiolabeling procedures with Tc-99m, Tc-99m GRFLT-ECG-ROX complexes were prepared in high yield (>96%). The binding affinity value (Kd ) of Tc-99m GRFLT-ECG-ROX for LNCaP cells was estimated to be 9.5 ± 1.3 nM. In gamma camera imaging, the tumor to normal muscle uptake ratios of Tc-99m GRFLT-ECG-ROX increased with time (3.1 ± 0.2, 4.0 ± 0.4, and 6.3 ± 0.9 at 1, 2, and 3 h, respectively). Under real-time optical imaging, the removal of visible nodules was successfully performed. Thus, Tc-99m GRFLT-ECG-ROX could provide both preoperative molecular imaging and fluorescence imaging guidance for tumor removal.


Assuntos
Neoplasias da Próstata , Animais , Fluorescência , Masculino , Camundongos , Imagem Molecular , Distribuição Tecidual
9.
Korean J Physiol Pharmacol ; 24(1): 69-79, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31908576

RESUMO

Aging is one of the risk factors for the development of cardiovascular diseases. During the progression of cellular senescence, cells enter a state of irreversible growth arrest and display resistance to apoptosis. As a flavonoid, quercetin induces apoptosis in various cells. Accordingly, we investigated the relationship between quercetin-induced apoptosis and the inhibition of cellular senescence, and determined the mechanism of oxidative stress-induced vascular smooth muscle cell (VSMC) senescence. In cultured VSMCs, hydrogen peroxide (H2O2) dose-dependently induced senescence, which was associated with increased numbers of senescence-associated ß-galactosidase-positive cells, decreased expression of SMP30, and activation of p53-p21 and p16 pathways. Along with senescence, expression of the anti-apoptotic protein Bcl-2 was observed to increase and the levels of proteins related to the apoptosis pathway were observed to decrease. Quercetin induced apoptosis through the activation of AMP-activated protein kinase. This action led to the alleviation of oxidative stress-induced VSMC senescence. Furthermore, the inhibition of AMPK activation with compound C and siRNA inhibited apoptosis and aggravated VSMC senescence by reversing p53-p21 and p16 pathways. These results suggest that senescent VSMCs are resistant to apoptosis and quercetin-induced apoptosis attenuated the oxidative stress-induced senescence through activation of AMPK. Therefore, induction of apoptosis by polyphenols such as quercetin may be worthy of attention for its anti-aging effects.

10.
Med Sci Monit ; 25: 8438-8446, 2019 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-31705647

RESUMO

BACKGROUND Hypernatremia is associated with poor outcomes in critically ill patients, and an accurate assessment of water volume is important to determine appropriate fluid hydration. Bioelectrical impedance analysis (BIA) is a new, noninvasive, and relatively easy method for measuring hydration status. This study aimed to investigate whether bioelectrical impedance measurements of body water could reduce the frequency of blood sampling for fluid replacement in patients with hypernatremia. MATERIAL AND METHODS Fifty-one hospitalized patients were studied with hypernatremia, defined as a serum sodium ≥150 mmol/L determined by laboratory testing. Laboratory and BIA measurements were compared, and water deficiency was calculated with a conventional formula (sodium-corrected Watson formula) and measured by BIA. RESULTS The value of the absolute fluid overload (AFO) equivalent to the overhydration (OH) value, determined using BIA, did not accurately represent water deficit in patients with hypernatremia (r=0.137, P=0.347). Although the total body water (TBW) measured by BIA showed a significant correlation with that determined by the conventional formula (r=0.861, P<0.001), there was a proportional bias (r=0.617, P<0.001). The intracellular water (ICW) measured by BIA underestimated the TBW level calculated by the conventional formula by about 14.06±4.0 L in the Bland-Altman analysis. CONCLUSIONS It is not currently possible to replace blood testing with BIA for assessing volume status in hypernatremic patients. However, ICW value measured by BIA might represent plasma sodium level more accurately than extracellular water (ECW) or TBW value in patients with hypernatremia.


Assuntos
Hipernatremia/diagnóstico , Hipernatremia/metabolismo , Estado de Hidratação do Organismo/fisiologia , Adulto , Composição Corporal , Água Corporal/fisiologia , Desidratação/diagnóstico , Impedância Elétrica , Espaço Extracelular , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Água
11.
BMC Musculoskelet Disord ; 20(1): 128, 2019 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-30917814

RESUMO

BACKGROUND: The purpose of this study was to examine the reliability of plain radiographic methods of determining the lunate type and its compatibility with magnetic resonance arthrography (MRA) findings. METHODS: Plain radiographs of a total of 150 wrists were reviewed by three observers. Lunate types were evaluated using both conventional posteroanterior (PA) radiographic analysis and the capitate-triquetrum distance (CTD) analysis. Cohen kappa and Fleiss kappa statistics were used to estimate intra- and inter-observer reliabilities. Compatibility with the MRA findings, as assessed by each observer, was investigated. RESULTS: The overall intra-observer reliability was 0.517 for the analysis and 0.589 for the CTD analysis. The overall inter-observer agreement was 0.448 for the PA radiographic analysis and 0.581 for the CTD analysis. The PA radiographic analysis and MRA findings for the detection of medial lunate facets were compatible in 119 of the 150 patients (79.3%). Twenty-eight (90.3%) of the 31 incompatible wrists had a medial facet on MRA (Type II), which was not detected in the PA radiographic analysis. In the CTD analysis, the results for 27 of 29 Type II lunates (93.1%) and 39 of 45 Type I lunates (86.7%) were compatible with the MRA. CONCLUSIONS: This study suggests that predicting the lunate type by plain radiographs alone is insufficient, as both radiographic analyses showed moderate intra- and inter-observer reliabilities. Although both radiographic analyses showed good compatibility with the MRA for Type II lunates, clinicians should be alert to undetected medial facets in Type I lunates on PA radiographic analysis.


Assuntos
Artrografia/métodos , Osso Semilunar/anatomia & histologia , Imageamento por Ressonância Magnética/métodos , Articulação do Punho/diagnóstico por imagem , Adulto , Feminino , Humanos , Osso Semilunar/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Adulto Jovem
12.
Int J Mol Sci ; 20(21)2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31661903

RESUMO

Herein, we describe the fabrication and characterization of carbonized disulfide core-crosslinked polymer dots with pH-cleavable colorimetric nanosensors, based on diol dye-conjugated fluorescent polymer dots (L-PD), for reduction-triggered paclitaxel (PTX) release during fluorescence imaging-guided chemotherapy of tumors. L-PD were loaded with PTX (PTX loaded L-PD), via π-π stackings or hydrophobic interactions, for selective theragnosis by enhanced release of PTX after the cleavage of disulfide bonds by high concentration of glutathione (GSH) in a tumor. The nano-hybrid system showed fluorescence quenching behavior with less than 2% of PTX released under physiological conditions. However, in a tumor microenvironment, the fluorescence recovered at an acidic-pH, and PTX (approximately 100% of the drug release) was released efficiently out of the matrix by reduction caused by the GSH level in the tumor cells, which improved the effectiveness of the cancer treatment. Therefore, the colorimetric nanosensor showed promising potential in distinguishing between normal and cancerous tissues depending on the surrounding pH and GSH concentrations so that PTX can be selectively delivered into cancer cells for improved cancer diagnosis and chemotherapy.


Assuntos
Antineoplásicos/administração & dosagem , Nanopartículas/química , Paclitaxel/administração & dosagem , Polímeros/química , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Técnicas Biossensoriais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Colorimetria , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Fluorescência , Glutationa/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Nanopartículas/ultraestrutura , Oxirredução , Paclitaxel/síntese química , Paclitaxel/química , Paclitaxel/uso terapêutico
13.
J Am Chem Soc ; 140(4): 1358-1364, 2018 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-29300468

RESUMO

Organic-inorganic halide perovskite is believed to be a potential candidate for high efficiency solar cells because power conversion efficiency (PCE) was certified to be more than 22%. Nevertheless, mismatch of PCE due to current density (J)-voltage (V) hysteresis in perovskite solar cells is an obstacle to overcome. There has been much lively debate on the origin of J-V hysteresis; however, effective methodology to solve the hysteric problem has not been developed. Here we report a universal approach for hysteresis-free perovskite solar cells via defect engineering. A severe hysteresis observed from the normal mesoscopic structure employing TiO2 and spiro-MeOTAD is almost removed or does not exist upon doping the pure perovskites, CH3NH3PbI3 and HC(NH2)2PbI3, and the mixed cation/anion perovskites, FA0.85MA0.15PbI2.55Br0.45 and FA0.85MA0.1Cs0.05PbI2.7Br0.3, with potassium iodide. Substantial reductions in low-frequency capacitance and bulk trap density are measured from the KI-doped perovskite, which is indicative of trap-hysteresis correlation. A series of experiments with alkali metal iodides of LiI, NaI, KI, RbI and CsI reveals that potassium ion is the right element for hysteresis-free perovskite. Theoretical studies suggest that the atomistic origin of the hysteresis of perovskite solar cells is not the migration of iodide vacancy but results from the formation of iodide Frenkel defect. Potassium ion is able to prevent the formation of Frenkel defect since K+ energetically prefers the interstitial site. A complete removal of hysteresis is more pronounced at mixed perovskite system as compared to pure perovskites, which is explained by lower formation energy of K interstitial (-0.65 V for CH3NH3PbI3 vs -1.17 V for mixed perovskite). The developed KI doping methodology is universally adapted for hysteresis-free perovskite regardless of perovskite composition and device structure.

14.
Amino Acids ; 50(11): 1583-1594, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30105541

RESUMO

Previously we have demonstrated transglutaminase 2 (TGase 2) inhibition abrogated renal cell carcinoma (RCC) using GK921 (3-(phenylethynyl)-2-(2-(pyridin-2-yl)ethoxy)pyrido[3,2-b]pyrazine), although the mechanism of TGase 2 inhibition remains unsolved. Recently, we found that the increase of TGase 2 expression is required for p53 depletion in RCC by transporting the TGase 2 (1-139 a.a)-p53 complex to the autophagosome, through TGase 2 (472-687 a.a) binding p62. In this study, mass analysis revealed that GK921 bound to the N terminus of TGase 2 (81-116 a.a), which stabilized p53 by blocking TGase 2 binding. This suggests that RCC survival can be stopped by p53-induced cell death through blocking the p53-TGase 2 complex formation using GK921. Although GK921 does not bind to the active site of TGase 2, GK921 binding to the N terminus of TGase 2 also inactivated TGase 2 activity through acceleration of non-covalent self-polymerization of TGase 2 via conformational change. This suggests that TGase 2 has an allosteric binding site (81-116 a.a) which changes the conformation of TGase 2 enough to accelerate inactivation through self-polymer formation.


Assuntos
Carcinoma de Células Renais/enzimologia , Proteínas de Ligação ao GTP/metabolismo , Neoplasias Renais/enzimologia , Proteínas de Neoplasias/metabolismo , Transglutaminases/metabolismo , Regulação Alostérica , Carcinoma de Células Renais/tratamento farmacológico , Linhagem Celular Tumoral , Proteínas de Ligação ao GTP/antagonistas & inibidores , Proteínas de Ligação ao GTP/genética , Células HEK293 , Humanos , Neoplasias Renais/tratamento farmacológico , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/genética , Domínios Proteicos , Proteína 2 Glutamina gama-Glutamiltransferase , Pirazinas/farmacologia , Transglutaminases/antagonistas & inibidores , Transglutaminases/genética
15.
Clin Orthop Relat Res ; 476(6): 1276-1283, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29698293

RESUMO

BACKGROUND: Quantitative assessment of rotator cuff muscle activity is important in the treatment of shoulder disorders. However, the known methods for assessing rotator cuff muscle activity thus far have been inaccurate, invasive, and inconvenient. QUESTIONS/PURPOSES: (1) Does the activity of the deltoid, supraspinatus, and infraspinatus muscles measured using ultrasound shear wave elastography have a linear correlation with muscle activity assessed using generally used methods, including isokinetic dynamometry and electromyography? (2) Does the activity of the deltoid, supraspinatus, and infraspinatus muscles measured using shear wave elastography show good intraobserver and interobserver reliability? METHODS: Twelve volunteers participated in intrasession reliability experiments. They were asked to perform isometric abduction, external rotation, and scaption contractions (defined as elevation of the arm within the plane of the scapula with neutral arm rotation) gradually increased from 0% to 75% of maximal voluntary contraction. The joint torque, electromyographic activity, and shear elastic modulus were synchronously measured in the middeltoid, supraspinatus, and infraspinatus muscles. The validity of the elastic modulus value was assessed using regression analysis between normalized torque and electromyographic root mean square values. For intraobserver and interobserver reliability measurements, repeated experiments were performed with the same protocol. RESULTS: The shear elastic modulus and normalized joint torque with isokinetic dynamometry showed a linear relationship in all muscles (deltoid, supraspinatus, and infraspinatus) and each of the ultrasonography planes (longitudinal and transverse) (mean R > 0.8 and p < 0.001 for all measurements). For the supraspinatus muscle, the mean slope of the relationship between shear elastic modulus in the longitudinal plane and the normalized joint torque during scaption contraction was 1.28 ± 0.39 kPa/%MVC (mean R = 0.93 ± 0.21, p < 0.001). Furthermore, similar results were obtained in relation to electromyography root mean square values (mean R > 0.8 and p < 0.001 in all measurements). For the supraspinatus muscle, the mean slope of the relationship between shear elastic modulus in the longitudinal plane and electromyographic (EMG) root mean square was 0.96 ± 0.27 kPa/%EMG (mean R = 0.91 ± 0.08, p < 0.001). The intraobserver and interobserver reliabilities were excellent in all positions (abduction, external rotation, and scaption) and in both the longitudinal and transverse ultrasonography planes (all intraclass correlation coefficients are > 0.85). CONCLUSIONS: Shoulder muscle activity can be noninvasively evaluated with ultrasound shear wave elastography. Clinician and scientists should consider the application of this technique in cases in which evaluation of shoulder muscle activity is required. The next step after this study will be to check the shear elastic modulus of rotator cuff muscle in patients with rotator cuff tear. We plan to evaluate the correlation between shear elastic modulus and joint torque according to tear size and fatty infiltration status of rotator cuff muscle. CLINICAL RELEVANCE: Shear wave electrography can be used to measure various tissue elasticities in both static and dynamic modes. It may be a useful tool to evaluate pre- and postoperative rotator cuff muscle activity in a relatively simple manner. Shoulder function after reverse total shoulder arthroplasty associated with deltoid muscle activity also may be evaluated. Changes in tissue tightness in shoulder disorders caused by increase soft tissue stiffness (ie, adhesive capsulitis and glenohumeral internal rotation deficit) can be evaluated.


Assuntos
Músculo Deltoide/diagnóstico por imagem , Módulo de Elasticidade , Técnicas de Imagem por Elasticidade/estatística & dados numéricos , Manguito Rotador/diagnóstico por imagem , Ombro/diagnóstico por imagem , Adulto , Fenômenos Biomecânicos , Músculo Deltoide/fisiologia , Técnicas de Imagem por Elasticidade/métodos , Eletromiografia/estatística & dados numéricos , Feminino , Voluntários Saudáveis , Humanos , Contração Isométrica , Masculino , Variações Dependentes do Observador , Amplitude de Movimento Articular , Análise de Regressão , Reprodutibilidade dos Testes , Rotação , Manguito Rotador/fisiologia , Ombro/fisiologia , Articulação do Ombro/diagnóstico por imagem , Articulação do Ombro/fisiologia , Torque
16.
J Labelled Comp Radiopharm ; 61(7): 557-566, 2018 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-29603784

RESUMO

We developed a Tc-99m and TAMRA-labeled peptide, Tc-99m arginine-arginine-leucine (RRL) peptide (TAMRA-GHEG-ECG-RRL), to target tumor cells and evaluated the diagnostic performance of Tc-99m TAMRA-GHEG-ECG-RRL as a dual-modality imaging agent for tumor in a murine model. TAMRA-GHEG-ECG-RRL was synthesized using Fmoc solid-phase peptide synthesis. Binding affinity and in vitro cellular uptake studies were performed. Gamma camera imaging, biodistribution, and ex vivo imaging studies were performed in murine models with PC-3 tumors. Tumor tissue slides were prepared and analyzed with immunohistochemistry using confocal microscopy. After radiolabeling procedures with Tc-99m, Tc-99m TAMRA-GHEG-ECG-RRL complexes were prepared in high yield (>96%). The Kd of Tc-99m TAMRA-GHEG-ECG-RRL determined by saturation binding was 41.7 ± 7.8 nM. Confocal microscopy images of PC-3 cells incubated with TAMRA-GHEG-ECG-RRL showed strong fluorescence in the cytoplasm. Gamma camera imaging revealed substantial uptake of Tc-99m TAMRA-GHEG-ECG-RRL in tumors. Tumor uptake was effectively blocked by the coinjection of an excess concentration of RRL. Specific uptake of Tc-99m TAMRA-GHEG-ECG-RRL was confirmed by biodistribution, ex vivo imaging, and immunohistochemistry stain studies. In conclusion, in vivo and in vitro studies revealed substantial uptake of Tc-99m TAMRA-GHEG-ECG-RRL in tumors. Tc-99m TAMRA-GHEG-ECG-RRL has potential as a dual-modality tumor imaging agent.


Assuntos
Corantes Fluorescentes/química , Imagem Multimodal/métodos , Peptídeos/química , Tecnécio/química , Animais , Transporte Biológico , Técnicas de Química Sintética , Feminino , Humanos , Marcação por Isótopo , Masculino , Camundongos , Células PC-3 , Peptídeos/farmacocinética , Distribuição Tecidual
17.
Nano Lett ; 17(7): 4270-4276, 2017 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-28586229

RESUMO

Anomalous current-voltage (J-V) hysteresis in perovskite (PSK) solar cell is open to dispute, where hysteresis is argued to be due to electrode polarization, dipolar polarization, and/or native defects. However, a correlation between those factors and J-V hysteresis is hard to be directly evaluated because they usually coexist and are significantly varied depending on morphology and crystallinity of the PSK layer, selective contacts, and device architecture. In this study, without changing morphology and crystallinity of PSK layer in a planar heterojunction structure employing FA0.9Cs0.1PbI3, a correlation between J-V hysteresis and trap density is directly evaluated by means of thermally induced PbI2 regulating trap density. Increase in thermal annealing time at a given temperature of 150 °C induces growth of PbI2 on the PSK grain surface, which results in significant reduction of nonradiative recombination. Hysteresis index is reduced from 0.384 to 0.146 as the annealing time is increased from 5 to 100 min due to decrease in the amplitude of trap-mediated recombination. Reduction of hysteresis by minimizing trap density via controlling thermal annealing time leads to the stabilized PCE of 18.84% from the normal planar structured FA0.9Cs0.1PbI3 PSK solar cell.

18.
Int Orthop ; 42(5): 1067-1074, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-28828747

RESUMO

PURPOSE: The purpose of this study was to assess post-operative patient subjective satisfaction and to analyze associated peri-operative factors following biplanar medial open wedge high tibial osteotomy (OWHTO). METHODS: The study cohort consisted of 88 patients with a minimum of two years of follow-up. Patient satisfaction was evaluated with a questionnaire that assessed (1) overall satisfaction, (2) pain relief, (3) daily living functions, and (4) cosmesis. Patients were categorized into two groups (satisfied or unsatisfied) based on overall satisfaction questionnaire. Pre- and post-operative objective clinical statuses were assessed with a knee scoring system based on the American Knee Society (AKS), the Western Ontario McMaster University Osteoarthritis Index (WOMAC), and range of motion. RESULTS: Of the 88 patients, 85.2% were graded as satisfied according to the overall satisfaction estimation. The percentage of patients satisfied with pain relief, daily living functions, and cosmesis were 85.2%, 86.4%, and 86.4%, respectively. Multivariable logistic regression analysis demonstrated that pre-operative Hip-Knee-Ankle angle (HKAA) (odds ratio (OR) = 1.812), post-operative AKS knee score (OR = 1.156), and post-operative HKAA (OR = 0.717) were significantly associated with overall satisfaction. Pre-operative HKAA (OR = 1.436), post-operative WOMAC activity score (OR = 0.865), and post-operative HKAA (OR = 0.505) were significant predictors for satisfaction with pain reduction, daily living functions, and cosmesis, respectively. CONCLUSIONS: Biplanar medial OWHTO is an effective treatment for osteoarthritis with varus deformity in terms of subjective satisfactory outcome. Several factors, including pre- and post-operative HKAA, post-operative AKS and WOMAC score, were significant predictors for subjective satisfaction. LEVEL OF EVIDENCE: Level III.


Assuntos
Articulação do Joelho/cirurgia , Osteoartrite do Joelho/cirurgia , Osteotomia/métodos , Satisfação do Paciente/estatística & dados numéricos , Tíbia/cirurgia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medidas de Resultados Relatados pelo Paciente , Amplitude de Movimento Articular , Resultado do Tratamento
19.
Biochem Biophys Res Commun ; 492(1): 128-134, 2017 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-28782520

RESUMO

Menin, encoded by the multiple endocrine neoplasia type 1 (MEN1) gene, is a tumor suppressor and transcription regulator. Menin interacts with various proteins as a scaffold protein and is proposed to play important roles in multiple physiological and pathological processes by controlling gene expression, proliferation, and apoptosis. The mechanisms underlying menin's suppression of tumorigenesis are largely elusive. In this study, we showed that menin was essential for the regulation of canonical Wnt/ß-catenin signaling in cultured cells. The C-terminal domain of menin was able to directly interact with and promote ubiquitin-mediated degradation of ß-catenin. We further revealed that overexpression of menin down-regulated the transcriptional activity of ß-catenin and target gene expression. Moreover, menin efficiently inhibited ß-catenin protein levels, transcriptional activity, and proliferation of human renal carcinoma cells with an activated ß-catenin pathway. Taken together, our results provide novel molecular insights into the tumor suppressor activity of menin, which is partly mediated by proteasomal degradation of ß-catenin and inhibition of Wnt/ß-catenin signaling.


Assuntos
Complexo de Endopeptidases do Proteassoma/metabolismo , Proteólise , Proteínas Proto-Oncogênicas/metabolismo , Ubiquitina/metabolismo , beta Catenina/metabolismo , Células Cultivadas , Células HEK293 , Humanos , Ligação Proteica
20.
J Labelled Comp Radiopharm ; 60(14): 649-658, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29023950

RESUMO

We developed a Tc-99m and fluorescence-labeled peptide, Tc-99m TAMRA-GHEG-ECG-VAPG to target tumor cells and evaluated the diagnostic performance as a dual-modality imaging agent for tumor in a murine model. TAMRA-GHEG-ECG-VAPG was synthesized by using Fmoc solid-phase peptide synthesis. Radiolabeling of TAMRA-GHEG-ECG-VAPG with Tc-99m was done by using ligand exchange via tartrate. Binding affinity and in vitro cellular uptake studies were performed. Gamma camera imaging, biodistribution, and ex vivo imaging studies were performed in murine models with SW620 tumors. Tumor tissue slides were prepared and analyzed with immunohistochemistry by using confocal microscopy. After radiolabeling procedures with Tc-99m, Tc-99m TAMRA-GHEG-ECG-VAPG complexes were prepared in high yield (>96%). The Kd of Tc-99m TAMRA-GHEG-ECG-VAPG determined by saturation binding was 16.8 ± 3.6 nM. Confocal microscopy images of SW620 cells incubated with TAMRA-GHEG-ECG-VAPG showed strong fluorescence in the cytoplasm. Gamma camera imaging revealed substantial uptake of Tc-99m TAMRA-GHEG-ECG-VAPG in tumors. Tumor uptake was effectively blocked by the coinjection of an excess concentration of VAPG. Specific uptake of Tc-99m TAMRA-GHEG-ECG-VAPG was confirmed by biodistribution, ex vivo imaging, and immunohistochemistry stain studies. In vivo and in vitro studies revealed substantial uptake of Tc-99m TAMRA-GHEG-ECG-VAPG in tumor cells. Tc-99m TAMRA-GHEG-ECG-VAPG has potential as a dual-modality tumor imaging agent.


Assuntos
Neoplasias Experimentais/diagnóstico por imagem , Oligopeptídeos/química , Compostos Radiofarmacêuticos/síntese química , Tecnécio/química , Animais , Linhagem Celular Tumoral , Feminino , Corantes Fluorescentes/química , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Compostos Radiofarmacêuticos/farmacocinética , Rodaminas/química , Distribuição Tecidual
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