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1.
Transplant Proc ; 56(2): 285-289, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38320870

RESUMO

BACKGROUND: Prostate cancer is common among male renal transplant recipients and can present challenges for medical management and patient survival. It is imperative to have a comprehensive understanding of available treatment options in this population to determine the most effective and safe therapies. Brachytherapy, a safe and effective treatment for localized prostate cancer, has not been sufficiently studied in this patient population. Therefore, this study aimed to evaluate the safety and effectiveness of brachytherapy in treating prostate cancer in renal transplant recipients. METHODS: We retrospectively reviewed our brachytherapy database to identify patients with a previous history of renal transplantation who underwent seed implantation for localized prostate cancer. Long-term prostate-specific antigen control and treatment-related toxicity, including graft dysfunction and urinary and rectal complications, were assessed and compared with published outcomes. Results were analyzed to evaluate the efficacy and safety of seed implantation in this patient population. RESULTS: We identified 2 patients with previous renal transplantation who underwent permanent seed implantation for localized prostate cancer. Follow-ups ranged from 53 to 57 months, and both patients remained free of prostate-specific antigen progression with normal graft function. No acute and late complications occurred. CONCLUSION: Brachytherapy is a safe and effective treatment option for post-renal transplant prostate cancer. Given the paucity of reports on brachytherapy in this population, the findings of this study, despite a small sample size, contribute to the increasing body of evidence supporting the use of brachytherapy in this patient population.


Assuntos
Braquiterapia , Transplante de Rim , Neoplasias da Próstata , Humanos , Masculino , Antígeno Prostático Específico , Transplante de Rim/efeitos adversos , Braquiterapia/efeitos adversos , Braquiterapia/métodos , Estudos Retrospectivos , Neoplasias da Próstata/radioterapia , Neoplasias da Próstata/cirurgia , Neoplasias da Próstata/complicações
2.
Adv Sci (Weinh) ; 11(10): e2307055, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38196298

RESUMO

Materials that intrinsically exhibit localized surface plasmon resonance (LSPR) in the visible region have been predominantly researched on nanoparticles (NPs) composed of coinage metals, namely Au, Ag, and Cu. Here, as a coinage metal-free intermetallic NPs, colloidal PtIn2 NPs with a C1 (CaF2 -type) crystal structure are synthesized by the liquid phase method, which evidently exhibit LSPR at wavelengths similar to face-centered cubic (fcc)-Au NPs. Computational simulations pointed out differences in the electronic structure and photo-excited electron dynamics between C1-PtIn2 and fcc-Au NPs; reduces interband transition and stronger screening with smaller number of bound d-electrons compare with fcc-Au are unique origins of the visible plasmonic nature of C1-PtIn2 NPs. These results strongly indicate that the intermetallic NPs are expected to address the development of alternative plasmonic materials by tuning their crystal structure and composition.

3.
IJU Case Rep ; 6(6): 394-397, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37928290

RESUMO

Introduction: Cholesterol crystal embolism is a rare microembolic disease caused by cholesterol crystals that can present with various symptoms after vascular surgery, catheterization, or anticoagulation therapy. We report a case of penile ulceration caused by cholesterol crystal embolism. Case presentation: A 72-year-old man undergoing maintenance dialysis for end-stage renal failure presented with penile pain and a black glans ulcer. Despite low-density lipoprotein apheresis, he was referred to our hospital because of lack of improvement. Based on his medical history and clinical presentation, including artificial vascular replacement and right toe amputation, cholesterol crystal embolism was suspected and partial penectomy was performed, thus confirming the diagnosis. Penile pain resolved after surgery, and he was discharged on Day 10. Unfortunately, he died after small bowel perforation developed 2 months after surgery. Conclusion: Penile ulcers caused by cholesterol crystal embolism may indicate the severity and progression of disease and typically require surgical intervention.

4.
ACS Omega ; 8(17): 15360-15370, 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-37151525

RESUMO

Bronze phase titanium dioxide (TiO2(B)) nanorods were successfully prepared via a hydrothermal method together with an ion exchange process and calcination by using anatase titanium dioxide precursors in the alkali hydrothermal system. TiO2 precursors promoted the elongation of nanorod morphology. The different hydrothermal temperatures and reaction times demonstrated that the synthesis parameters had a significant influence on phase formation and physical morphologies during the fabrication process. The effects of the synthesis conditions on the tailoring of the crystal morphology were discussed. The growth direction of the TiO2(B) nanorods was investigated by X-ray diffractometry (XRD) and scanning electron microscopy (SEM). The as-synthesized TiO2(B) nanorods obtained after calcination were used as anode materials and tested the efficiency of Li-ion batteries. This research will study the effects of particle morphologies and crystallinity of TiO2(B) derived from a modified hydrothermal method on the capacity and charging rate of the Li-ion battery. The TiO2(B) nanorods, which were synthesized by using a hydrothermal temperature of 220 °C for 12 h, presented excellent electrochemical performance with the highest Li storage capacity (348.8 mAh/g for 100 cycles at a current density of 100 mA/g) and excellent high-rate cycling capability (a specific capacity of 207.3 mAh/g for 1000 cycles at a rate of 5000 mA/g).

5.
Microscopy (Oxf) ; 72(4): 353-360, 2023 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-36440709

RESUMO

High-angle annular dark-field (HAADF) imaging and elemental mapping at the atomic scale by scanning transmission electron microscopy (STEM) combined with electron energy-loss spectroscopy (EELS) are widely used for material characterization, in which quantitative understanding of the contrast of the image is required. Here, we report an unexpected image contrast in the elemental mapping of rutile TiO2, where the Ti L2,3 map shows an anisotropic elliptical shape that extends along the long axis in the octahedral structure, while the atomic contrast of Ti columns in the HAADF image is almost circular. Multi-slice simulation reveals that unique electron channeling related to the rutile structure and the difference of the potentials between HAADF and EELS cause the different atomic contrasts in the two images.

6.
Ultramicroscopy ; 240: 113577, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35728341

RESUMO

The noise performance and the detection limits of a direct-counting complementary metal-oxide semiconductor (CMOS) K2 camera and a charge-coupled device (CCD) camera in electron energy loss spectroscopy (EELS) experiments were evaluated. In the case of a single spectrum acquired at the shortest dwell times (2.5 ms for K2 and 1 µs for CCD), the detection limit, defined as three times the standard deviation of the spectral noise (3σ), was very low (1 e-/channel) in the counting-mode spectrum acquired with the K2 camera compared with that acquired with the CCD camera (5 e-/channel). By contrast, the spectral noise of the K2 camera changed depending on the dwell time because of the multiple read-outs related to its fixed frame rate (400 fps). The spectral noise of the K2 camera was greater than that of the CCD camera when the dwell time was longer than ∼30 ms. Thus, the CCD camera was found to still be useful when detecting a very small number of electrons using a long acquisition time. In the case of an accumulated spectrum obtained by acquiring 10,000 spectra after subtracting the ultra-high-quality dark reference signal, the detection limits per read-out were ∼0.016 and ∼0.025 e-/channel/read-out for the K2 and CCD cameras, respectively. Because both cameras have advantages and disadvantages with respect to their detection limit, speed, and dynamic range, their proper use is important.

7.
In Vivo ; 36(4): 1847-1853, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35738641

RESUMO

BACKGROUND/AIM: In clinical practice, constipation is one of the most frequent adverse events caused by drugs for overactive bladder (OAB). The occurrence of constipation greatly deteriorates the patient's quality of life. The aim of the study was to evaluate and compare the effects of three commonly used ß3 agonists and anticholinergic drugs on the defecation status in patients with OAB. PATIENTS AND METHODS: We retrospectively reviewed the defecation status in patients who received mirabegron, solifenacin, or fesoterodine for OAB. We evaluated changes in the (a) urological parameters using the OAB symptom score (OABSS) and (b) defecation status using the Bristol Stool Form Scale (BSFS) and constipation scoring system (CSS) following 12 weeks of drug administration. RESULTS: We analyzed data from 165 patients (mirabegron=56, fesoterodine=52, and solifenacin=57). The solifenacin group showed a significant decrease in BSFS (from 3.2±1.0 at baseline to 2.3±12 post-treatment) and an increase in hardened stools (p<0.001). Elimination worsened as assessed by almost all items, and the total modified CSS scores worsened significantly from 4.8±2.6 points at baseline to 8.O±4.8 points after 12 weeks of solifenacin treatment (p<0.001). The mirabegron group showed no changes in any of the CSS items. In the fesoterodine group, the CSS scores for "completeness" and "assistance" increased significantly after treatment (p<0.001 and p=0.013, respectively). CONCLUSION: All three drugs were effective for OAB. Mirabegron had almost no effect on constipation; fesoterodine, an anticholinergic drug, also had hardly any effect on defecation.


Assuntos
Bexiga Urinária Hiperativa , Agentes Urológicos , Antagonistas Colinérgicos/efeitos adversos , Constipação Intestinal/induzido quimicamente , Constipação Intestinal/tratamento farmacológico , Defecação , Humanos , Qualidade de Vida , Estudos Retrospectivos , Succinato de Solifenacina/efeitos adversos , Resultado do Tratamento , Bexiga Urinária Hiperativa/induzido quimicamente , Bexiga Urinária Hiperativa/tratamento farmacológico , Bexiga Urinária Hiperativa/epidemiologia , Agentes Urológicos/efeitos adversos
8.
RSC Adv ; 12(23): 14621-14630, 2022 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-35702249

RESUMO

By combining rice husk-derived nano-silica and reduced graphene oxide and then polymerizing PANI by in situ polymerization, we created polyaniline-coated rice husk-derived nano-silica@reduced graphene oxide (PANI-SiO2@rGO) composites with excellent electrochemical performance. ATR-FTIR and XRD analyses confirm the formation of PANI-SiO2@rGO, implying that SiO2@rGO served as a template in the formation of composites. The morphology of PANI-SiO2@rGO was characterized by SEM, HRTEM, and STEM, in which SiO2 nanoparticles were homogeneously loaded on graphene sheets and the PANI fibrous network uniformly covers the SiO2@rGO composites. The structure can withstand the large volume change as well as retain electronic conductivity during Li-ion insertion/extraction. Over 400 cycles, the assembled composite retains a high reversible specific capacity of 680 mA h g-1 at a current density of 0.4 A g-1, whereas the SiO2@rGO retains only 414 mA h g-1 at 0.4 A g-1 after 215 cycles. The enhanced electrochemical performance of PANI-SiO2@rGO was a result of the dual protection provided by the PANI flexible layer and graphene sheets. PANI-SiO2@rGO composites may pave the way for the development of advanced anode materials for high-performance lithium-ion batteries.

9.
Anticancer Res ; 42(5): 2311-2317, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35489728

RESUMO

BACKGROUND/AIM: WW and C2 domain-containing 1 (WWC1) protein is a suppressor of malignancies. However, there is no information on the pathological significance of WWC1 in upper urinary tract cancer (UTUC). PATIENTS AND METHODS: In this study, WWC1 immunoreactivity was investigated in 152 non-metastatic UTUC samples. The relationships between WWC1 expression and grade, pT stage, proliferative index (using an antibody to Ki-67), and the immunohistochemical expression of matrix metalloproteinase (MMP)-2 and -9 were evaluated. RESULTS: WWC1 expression was negatively associated with tumor grade and pT stage (p<0.001). Positive expression of WWC1 was a better predictor of the UTUC recurrence and subsequent metastasis, and the multivariate analysis showed that WWC1 expression was a significant predictor of subsequent metastasis (hazard ratio=0.29, p=0.020). WWC1 expression inversely correlated with the proliferative index (odds ratio=2.59, p=0.023) and expression of MMP9 (odds ratio=2.19, p=0.040) but not with MMP2 expression, by multivariate analyses. CONCLUSION: WWC1 expression was negatively associated with malignant aggressiveness via the suppression of cancer cell proliferation and MMP9 expression in patients with UTUC. This suggests WWC1 to be a useful predictor and novel therapeutic target in patients with UTUC.


Assuntos
Carcinoma de Células de Transição , Neoplasias Renais , Neoplasias Ureterais , Neoplasias Urológicas , Carcinoma de Células de Transição/patologia , Feminino , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Neoplasias Renais/patologia , Pelve Renal/patologia , Masculino , Metaloproteinase 9 da Matriz , Prognóstico , Neoplasias Ureterais/patologia , Neoplasias Urológicas/patologia
10.
Nat Commun ; 13(1): 1047, 2022 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-35210441

RESUMO

An infinite number of crystal structures in a multicomponent alloy with a specific atomic ratio can be devised, although only thermodynamically-stable phases can be formed. Here, we experimentally show the first example of a layer-structured pseudo-binary alloy, theoretically called Z3-FePd3. This Z3 structure is achieved by adding a small amount of In, which is immiscible with Fe but miscible with Pd and consists of an alternate L10 (CuAu-type)-PdFePd trilayer and Pd-In ordered alloy monolayer along the c axis. First-principles calculations strongly support that the specific inter-element miscibility of In atoms stabilizes the thermodynamically-unstable Z3-FePd3 phase without significantly changing the original density of states of the Z3-FePd3 phase. Our results demonstrate that the specific inter-element miscibility can switch stable structures and manipulate the material nature with a slight composition change.

11.
ACS Chem Biol ; 17(3): 567-575, 2022 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-35188733

RESUMO

The present study reports a surprising protein-condensing effect of glucose, prompted by our accidental observation during chemical library screening under a high-glucose condition. We noticed "glucosing-out" of certain compounds, in which physiological concentrations of glucose induced compound aggregation. Adapting the "glucosing-out" concept to proteins, our proteomic analysis identified three cellular proteins (calmodulin, rho guanine nucleotide exchange factor 40, and polyubiquitin-C) that displayed robust glucose-dependent precipitation. One of these proteins, calmodulin, formed glucose-dependent condensates that control cellular glycogenolysis in hepatic cells. Our findings suggest that glucose is a heretofore underappreciated driver of protein phase separation that may have profound effects on cellular homeostasis.


Assuntos
Glucose , Glicogenólise , Calmodulina/metabolismo , Glucose/metabolismo , Homeostase , Proteômica
12.
Sci Rep ; 11(1): 20279, 2021 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-34645904

RESUMO

Prostaglandin E2 plays an important role in carcinogenesis and malignant potential of prostate cancer (PC) cells by binding to its specific receptors, E-type prostanoid (EP) receptors. However, anti-carcinogenic effects of the EP receptor antagonist are unclear. In this study, we used a mouse model of PC. The mice were provided standard feed (control) or feed containing the EP1 receptor antagonist and were sacrificed at 10, 15, 30, and 52 weeks of age. Apoptosis was evaluated by immunohistochemical analysis using a cleaved caspase-3 assay. The incidence of cancer in the experimental group was significantly lower than that in the control group at 15, 30, and 52 weeks of age. The percentage of poorly differentiated PC cells was significantly lower in the experimental group than in the control group at 30 and 52 weeks of age. The percentage of apoptotic cells in the experimental group was significantly higher than that in the control group at 15, 30, and 52 weeks of age. These findings indicate that feeding with the addition of EP1 receptor antagonist delayed PC progression via the upregulation of apoptosis. We suggest that the EP1 receptor antagonist may be a novel chemopreventive agent for PC.


Assuntos
Apoptose , Regulação Neoplásica da Expressão Gênica , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Receptores de Prostaglandina E Subtipo EP1/administração & dosagem , Administração Oral , Animais , Anticarcinógenos/farmacologia , Carcinogênese , Caspase 3/metabolismo , Modelos Animais de Doenças , Progressão da Doença , Imuno-Histoquímica , Masculino , Camundongos , Metástase Neoplásica , Regulação para Cima
13.
Angew Chem Int Ed Engl ; 60(2): 961-969, 2021 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-32979004

RESUMO

Immune potentiators, termed adjuvants, trigger early innate immune responses to ensure the generation of robust and long-lasting adaptive immune responses of vaccines. Presented here is a study that takes advantage of a self-assembling small-molecule library for the development of a novel vaccine adjuvant. Cell-based screening of the library and subsequent structural optimization led to the discovery of a simple, chemically tractable deoxycholate derivative (molecule 6, also named cholicamide) whose well-defined nanoassembly potently elicits innate immune responses in macrophages and dendritic cells. Functional and mechanistic analyses indicate that the virus-like assembly enters the cells and stimulates the innate immune response through Toll-like receptor 7 (TLR7), an endosomal TLR that detects single-stranded viral RNA. As an influenza vaccine adjuvant in mice, molecule 6 was as potent as Alum, a clinically used adjuvant. The studies described here pave the way for a new approach to discovering and designing self-assembling small-molecule adjuvants against pathogens, including emerging viruses.


Assuntos
Adjuvantes Imunológicos/química , Amidas/química , Amidas/imunologia , Amidas/farmacologia , Animais , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Células Dendríticas/citologia , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Ácido Desoxicólico/química , Avaliação Pré-Clínica de Medicamentos , Corantes Fluorescentes/química , Imunidade Inata , Imunoglobulina G/sangue , Vacinas contra Influenza/química , Vacinas contra Influenza/imunologia , Interleucina-6/metabolismo , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Nanoestruturas/química , Células RAW 264.7 , Relação Estrutura-Atividade , Receptor 7 Toll-Like/metabolismo
14.
Chem Commun (Camb) ; 56(85): 12941-12944, 2020 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-32975546

RESUMO

We synthesized a palladium-ruthenium-boron (Pd-Ru-B) solid-solution ternary alloy. Elemental mappings confirmed successful alloying of B with Pd-Ru body without changing the particle sizes, demonstrating the first discovery of this ternary alloy. Pair distribution function analysis revealed a drastic decrease in atomic correlation in Pd-Ru nanoparticles by B doping. This result gives the first example of structural transformation from crystalline to amorphous in solid-solution alloy nanoparticles induced by the doping of light elements.

15.
J Phys Chem A ; 124(9): 1735-1743, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-32040325

RESUMO

High energy resolution energy-loss near-edge structures (ELNES) at the carbon K-edge of copper phthalocyanine (CuPc) and its chlorinated molecular crystals were observed using electron energy-loss spectroscopy combined with a scanning transmission electron microscope equipped with a monochromator. The ELNES spectra were investigated using first-principles band structure calculations with a core-hole introduced into the 1s orbitals of the nonequivalent C atoms. The calculated spectra including half a core-hole were consistent with the experimental spectra. The spectral features could be interpreted in terms of the different contributions of the partial density of states (PDOS) of nonequivalent C atoms with different transition energies depending on the site. The core-hole effects were also discussed using the spatial distribution of unoccupied states and PDOSs, which revealed site-dependent core-hole effects, where a C atom with a strong spatial distribution intensity of the unoccupied states in the ground state (GS) are susceptible to the core-hole effects. The spectral changes due to chlorination of the CuPc molecule were mainly attributed to an increase of the threshold energy of the C atoms bonded to chlorine, and the influence of the change in the PDOS by chlorination was not significantly large.

16.
RSC Adv ; 10(71): 43811-43824, 2020 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-35519673

RESUMO

Emerging technologies demand a new generation of lithium-ion batteries that are high in power density, fast-charging, safe to use, and have long cycle lives. This work reports charging rates and specific capacities of TiO2(B)/N-doped graphene (TNG) composites. The TNG composites were prepared by the hydrothermal method in various reaction times (3, 6, 9, 12, and 24 h), while the N-doped graphene was synthesized using the modified Hummer's method followed by a heat-treatment process. The different morphologies of TiO2 dispersed on the N-doped graphene sheet were confirmed as anatase-nanoparticles (3, 6 h), TiO2(B)-nanotubes (9 h), and TiO2(B)-nanorods (12, 24 h) by XRD, TEM, and EELS. In electrochemical studies, the best battery performance was obtained with the nanorods TiO2(B)/N-doped graphene (TNG-24h) electrode, with a relatively high specific capacity of 500 mA h g-1 at 1C (539.5 mA g-1). In long-term cycling, excellent stability was observed. The capacity retention of 150 mA h g-1 was observed after 7000 cycles, at an ultrahigh current of 50C (27.0 A g-1). The synthesized composites have the potential for fast-charging and have high stability, showing potential as an anode material in advanced power batteries for next-generation applications.

17.
Inorg Chem ; 59(1): 343-349, 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31820944

RESUMO

High-pressure, high-temperature reaction conditions can be useful to stabilize metastable polymorphs of complex transition metal oxides. We successfully prepare a new defect pyrochlore Pb2FeTeO6.5 with B-site disordered Fe and Te cations under ambient conditions. Treatment of this material under 8 GPa and 950 °C results in a reductive transformation into the B-site cation-ordered double perovskite Pb2FeTeO6. Mössbauer and EELS spectroscopy confirm the iron cations are in the +3 oxidation state in both phases indicating that this transformation proceeds via reduction of the tellurium cations under apparently oxidizing conditions. This reaction demonstrates that for a suitably chosen system, it is possible to carry out chemical reactions under pressure in unexpected ways.

18.
Ultramicroscopy ; 207: 112827, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31445356

RESUMO

Extremely low count detection for EELS spectrum imaging is required to overcome problems with electron irradiation and widen the range of available applications. We have made a systematic statistical study of the reduction of CCD noise for EELS. We propose a calculation method to estimate the properties of noise and a procedure to reduce it. Since the dominant noise is a practically random component, it can be reduced by subtracting the population mean of the dark reference and a summation over an appropriate number of spectra, depending on the standard deviation of the noise. A gain-averaging method can further improve the signal-to-noise (SN) ratio. It is thereby demonstrated that a high-SN spectrum can be obtained even for a single-count core-loss signal. The present method would be useful for measuring low signal spectrum such as monochromated spectra and for radiation sensitive materials.

19.
ACS Nano ; 13(7): 8356-8363, 2019 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-31282648

RESUMO

Controlling the carrier dynamics in a semiconductor nanoparticulate photocatalyst is the key to developing catalytic activity. Generally, type I band alignment is unsuitable for photocatalysts because the photoinduced carriers accumulate in the narrow bandgap semiconductor. To avoid the termination of reactions and/or photocorrosion of materials caused by carrier accumulation, it is common to employ type II band alignment for photoenergy conversion systems instead of type I. However, CdS/ZnS core/mesoporous-shell heterostructures show superior photocatalytic activity despite having type I band alignment that is generally unfavorable for photocatalytic reactions. Transient absorption spectroscopy and time-resolved microwave conductivity revealed efficient photoinduced hole transfer from the CdS phase to the ZnS phase. The defect-mediated hole transfer from the CdS to the ZnS phase resulted in long-lived charge separation (>2.4 ms) leading to high photocatalytic performance. This study provides insight into defect-mediated carrier transfer in nanoparticulate photocatalysts, which could be used as a guideline for the design of highly active and stable nanoparticulate photocatalysts.

20.
Nat Mater ; 18(7): 685-690, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31133731

RESUMO

Symmetry breaking is a fundamental concept that prevails in many branches of physics1-5. In magnetic materials, broken inversion symmetry induces the Dzyaloshinskii-Moriya interaction (DMI), which results in fascinating physical behaviours6-14 with the potential for application in future spintronic devices15-17. Here, we report the observation of a bulk DMI in GdFeCo amorphous ferrimagnets. The DMI is found to increase linearly with an increasing thickness of the ferrimagnetic layer, which is a clear signature of the bulk nature of DMI. We also found that the DMI is independent of the interface between the heavy metal and ferrimagnetic layer. This bulk DMI is attributed to an asymmetric distribution of the elemental content in the GdFeCo layer, with spatial inversion symmetry broken throughout the layer. We expect that our experimental identification of a bulk DMI will open up additional possibilities to exploit this interaction in a wide range of materials.

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