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1.
Phys Rev Lett ; 126(15): 157402, 2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33929244

RESUMO

X-ray magnetic circular dichroism (XMCD) is generally not observed for antiferromagnetic (AFM) states because XMCD signals from the antiparallelly coupled spins cancel each other. In this Letter, we theoretically show the presence of an XMCD signal from compensated two-dimensional triangle AFM structures on a Kagome lattice. The calculation reveals the complete correspondence between the XMCD spectra and the sign of the spin chirality: the XMCD signal only appears when the spin chirality is negative. This XMCD signal originates from the different absorption coefficients of the three sublattices reflecting different charge density anisotropies and directions of spin and orbital magnetic moments.

2.
Foods ; 10(3)2021 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-33802975

RESUMO

Vertical indoor farming under artificial lighting has gained attention as a novel means of food production. However, consumer acceptance of vegetable crops grown under artificial conditions is not well understood. Our nationwide online survey of 289 Russians gathered attitudes and opinions toward vertically farmed vegetables. Employing an ordered logit model and a two-mode co-occurrence network analysis, we show how respondents' attitudes relate to their key demographic characteristics and opinions about the vegetables. Results indicate that respondents' attitudes are heterogeneous and related to their region of residence, income level, and opinions regarding nutrients, safety, and taste. Respondents in the Central and Volga districts exhibited less favorable attitudes. Less favorably inclined respondents viewed the produce as unnatural, less nutritious, bad-tasting, and even dangerous, presumably because of misconceptions or lack of knowledge. On the other hand, respondents with monthly income above RUB 60,001 (1018 USD, 867 EURO) had relatively positive attitudes toward such vegetables. Respondents having positive attitudes saw the vegetables as safe, tasty, and of good quality. We discuss the political and commercial implications of these findings.

3.
Dev Dyn ; 2021 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-33913218

RESUMO

BACKGROUND: The cellular and molecular mechanisms initiating vertebrate cranial dermal bone formation is a conundrum in evolutionary and developmental biology. Decades of studies have determined the developmental processes of cranial dermal bones in various vertebrates and identified possible inducers of dermal bone. However, evolutionarily derived characters of current experimental model organisms, such as non-homologous frontal bones between teleosts and sarcopterygians, hinder investigations of ancestral and conserved mechanisms of vertebrate cranial dermal bone induction. Thus, investigating such mechanisms with animals diverging at evolutionarily informative phylogenetic nodes is imperative. RESULTS: We investigated the cellular foundations of skull frontal bone formation in the spotted gar Lepisosteus oculatus, a basally branching non-teleost actinopterygian. Whole-mount bone and cartilage staining and hematoxylin-eosin section staining revealed that mesenchymal cell condensations in the frontal bone of spotted gar develop in close association with the underlying cartilage. We also identified novel aspects of frontal bone formation: enrichment of F-actin, cellular membranes, and E-cadherin in condensing cells, and extension of podia-like structures from osteoblasts to the frontal bone, which may be responsible for bone mineral transport. CONCLUSION: This study highlights the process of frontal bone formation with dynamic architectural changes of mesenchymal cells in spotted gar, an emerging non-teleost fish model system, illuminating supposedly ancestral and likely conserved developmental mechanisms of skull bone formation among vertebrates.

4.
J Crohns Colitis ; 2021 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-33596306

RESUMO

BACKGROUND AND AIMS: Ulcerative colitis (UC) is a chronic inflammatory disease of the colon with an intractable course. Although the goal of UC therapy is to achieve mucosal healing, the pathogenesis of mucosal injury caused by chronic inflammation remains unknown. We therefore aim to elucidate molecular mechanisms of mucosal injury by establishing in vitro and in vivo humanized UC mimicking models. METHODS: An in vitro model using human colon organoids was established by 60 weeks of inflammatory stimulation. The key gene for mucosal injury caused by long-term inflammation was identified by microarray analysis. An in vivo model was established by xenotransplantation of organoids into mouse colonic mucosa. RESULTS: An in vitro model demonstrated that long-term inflammation induced irrecoverable changes in organoids: inflammatory response and apoptosis with oxidative stress and suppression of cell viability. This model also mimicked organoids derived from patients with UC at the gene expression and phenotype levels. Microarray analysis revealed Schlafen11 (SLFN11) was irreversibly induced by long-term inflammation. Consistently, SLFN11 was highly expressed in UC mucosa but absent in normal mucosa. The knockdown of SLFN11 (SLFN11-KD) suppressed apoptosis of IECs induced by inflammation. Moreover, SLFN11-KD improved the take rates of xenotransplantation and induced regenerative changes of crypts observed in patients with UC in remission. CONCLUSIONS: In vitro and in vivo UC mimicking models were uniquely established using human colonic organoids. They revealed SLFN11 is significant for mucosal injury in UC, and its potential as a novel target for mucosal regeneration.

5.
Biochem Biophys Res Commun ; 542: 17-23, 2021 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-33482469

RESUMO

Nickel, the most frequent contact allergy cause, is widely used for various metallic materials and medical devices. Autophagy is an intracellular protein degradation system and contributes to metal recycling. However, it is unclear the functions of nickel in autophagy. We here demonstrated that NiCl2 induced microtubule-associated protein 1 light chain 3 (LC3)-II and LC3 puncta, markers of autophagosomes. Bafilomycin A1 (BafA1) treatment did not enhance LC3 puncta under NiCl2 stimulation, suggesting that NiCl2 did not induce autophagic flux. In addition, NiCl2 promotes the accumulation of SQSTM1/p62 and increased SQSTM1/p62 colocalization with lysosomal-associated membrane protein 1 (LAMP1). These data indicated that NiCl2 attenuates autophagic flux. Interestingly, NiCl2 induced the expression of the high-molecular-weight (MW) form of SQSTM1/p62. Inhibition of NiCl2-induced reactive oxygen species (ROS) reduced the high-MW SQSTM1/p62. We also showed that NiCl2-induced ROS activate transglutaminase (TG) activity. We found that transglutaminase 2 (TG2) inhibition reduced high-MW SQSTM1/p62 and SQSTM1/p62 puncta under NiCl2 stimulation, indicating that TG2 regulates SQSTM1/p62 protein homeostasis under NiCl2 stimulation. Our study demonstrated that nickel ion regulates autophagy flux and TG2 restricted nickel-dependent proteostasis.

6.
Cell Mol Gastroenterol Hepatol ; 11(5): 1483-1503, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33515805

RESUMO

BACKGROUND & AIMS: The reason why small intestinal cancer is rarer than colorectal cancer is not clear. We hypothesized that intraepithelial lymphocytes (IELs), which are enriched in the small intestine, are the closest immune cells to epithelial cells, exclude tumor cells via cell-to-cell contact. METHODS: We developed DPE-green fluorescent protein (DPE-GFP) × adenomatous polyposis coli; multiple intestinal neoplasia (APCmin ) mice, which is a T-cell-reporter mouse with spontaneous intestinal tumors. We visualized the dynamics of IELs in the intestinal tumor microenvironment and the interaction between IELs and epithelial cells, and the roles of cell-to-cell contact in anti-intestinal tumor immunity using a novel in vivo live-imaging system and a novel in vitro co-culture system. RESULTS: In the small intestinal tumor microenvironment, T-cell movement was restricted around blood vessels and the frequency of interaction between IELs and epithelial cells was reduced. Genetic deletion of CD103 decreased the frequency of interaction between IELs and epithelial cells, and increased the number of small intestinal tumors. In the co-culture system, wild-type IELs expanded and infiltrated to intestinal tumor organoids from APCmin mice and reduced the viability of them, which was cell-to-cell contact and CD103 dependent. CONCLUSIONS: The abundance of IELs in the small intestine may contribute to a low number of tumors, although this system may not work in the colon because of the sparseness of IELs. Strategies to increase the number of IELs in the colon or enhance cell-to-cell contact between IELs and epithelial cells may be effective for the prevention of intestinal tumors in patients with a high cancer risk.

7.
Oncotarget ; 11(34): 3198-3207, 2020 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-32922660

RESUMO

Liquid biopsy is a non-invasive tool to examine the genetic profile of tumors by identification of mutated circulating tumor DNA (ctDNA), which is often analyzed by next generation sequencing (NGS) or droplet digital PCR (ddPCR) assay. We first examined the ctDNA mutation in pre-operative plasma samples obtained from 154 colorectal cancer (CRC) and 46 gastric cancer (GC) patients, using the NGS-based panel assay. The overall detection rate of mutated ctDNA was 72.0% (144 of 200 patients), and the panel-based screening identified 207 and 47 mutations from CRC and GC patients, respectively. The ddPCR analysis was then performed on post-operative samples of 77 patients, and detection of mutated ctDNA was earlier than imaging-based diagnosis in all of 6 patients who showed the tumor recurrences after surgery. Our data also revealed that patients with positive post-operation ctDNA level showed significant shorter recurrence-free survival compared to the patients with negative ctDNA level (HR 14.9; 95% CI, 0.7-313.5; p < 0.0001). These findings suggested that screening of mutated ctDNA by liquid biopsy aids in identifying the patients at high risk of post-operative recurrence, and serial screening of ctDNA would allow to monitor the response after treatment and/or early detection of tumor recurrence.

8.
Anal Sci ; 36(11): 1337-1343, 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-32565526

RESUMO

Hydrophobic and volatile flavor molecules can be encapsulated inside cyclodextrins (CyDs). Inclusion complexes are frequently used in solid or dispersed states in preserved food and cosmetics. In this study, the solid-state structures of spray-dried inclusion complexes of l-menthol in α-CyD and ß-CyD were analyzed using 13C solid-state NMR and vibrational circular dichroism (VCD). The NMR signals of l-menthol and CyDs were identified in the physical mixture and the l-menthol inclusion complex of α- and ß-CyD. The NMR signal of the isopropyl-methyl group of menthol in the α-CyD inclusion complex exhibited a large low-field shift, which suggested a steric hindrance between menthol and α-CyD. VCD exhibited specific changes in the intensity of bands corresponding to C-C vibrations in α-CyD and O-C stretching vibrations in l-menthol. Our results indicated that l-menthol specifically fitted the narrow space within α-CyD. The combined solid-state NMR and VCD analysis provided structural insights into the flavor inclusion complex in the solid-state.

9.
Dev Growth Differ ; 62(5): 311-325, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32396685

RESUMO

The fish fin is a breathtaking repository full of evolutionary diversity, novelty, and convergence. Over 500 million years, the adaptation to novel habitats has provided landscapes of fin diversity. Although comparative anatomy of evolutionarily divergent patterns over centuries has highlighted the fundamental architectures and evolutionary trends of fins, including convergent evolution, the developmental constraints on fin evolution, which bias the evolutionary trajectories of fin morphology, largely remain elusive. Here, we review the evolutionary history, developmental mechanisms, and evolutionary underpinnings of paired fins, illuminating possible developmental constraints on fin evolution. Our compilation of anatomical and genetic knowledge of fin development sheds light on the canalized and the unpredictable aspects of fin shape in evolution. Leveraged by an arsenal of genomic and genetic tools within the working arena of spectacular fin diversity, evolutionary developmental biology embarks on the establishment of conceptual framework for developmental constraints, previously enigmatic properties of evolution.

10.
Antioxidants (Basel) ; 9(1)2020 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-31963934

RESUMO

Therapeutic applications of coenzyme Q10 (CoQ10) are greatly limited by its lack of solubility in aqueous media. In this study, polyethylene glycol monostearate (stPEG) was used to construct micelles containing CoQ10 as a new formulation. The micellar formulations (stPEG/CoQ10) were prepared using five types of stPEG with 10, 25, 40, 55, and 140 PEG repeat units, respectively. The micellar preparation was simple, consisting of only stPEG and CoQ10. Next, we compared the physical properties and blood circulation of these micelles. The CoQ10 load of this formulation was approximately 15 w/w%. Based on the dynamic light scattering method, the average molecular size of the stPEG/CoQ10 micelles was approximately 15 to 60 nm. The zeta potentials of these micelles were approximately -10 to -25 mV. The micelles using stPEG25, 40, and 55 demonstrated high solubility in water. Furthermore, these micelles had in vitro antioxidant activity. On comparing the blood circulation of micelles using stPEG25, 40, 55, and 140, micelles using stPEG55 had a significantly higher circulation in blood. The stPEG55/CoQ10 micelle demonstrated a protective effect against acetaminophen-induced liver injury in mice. In conclusion, these data indicate that the intravenous administration of the stPEG/CoQ10 micellar aqueous formulation is of great value against oxidant stress.

11.
FEBS Lett ; 594(10): 1586-1595, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31997355

RESUMO

Autophagy is an intracellular process that regulates the degradation of cytosolic proteins and organelles. Dying cells often accumulate autophagosomes. However, the mechanisms by which necroptotic stimulation induces autophagosomes are not defined. Here, we demonstrate that the activation of necroptosis with TNF-α plus the cell-permeable pan-caspase inhibitor Z-VAD induces LC3-II and LC3 puncta, markers of autophagosomes, via the receptor-interacting protein kinase 3 (RIPK3) in intestinal epithelial cells. Surprisingly, necroptotic stimulation reduces autophagic activity, as evidenced by enlarged puncta of the autophagic substrate SQSTM1/p62 and its increased colocalization with LC3. However, necroptotic stimulation does not induce the lysosomal-associated membrane protein 1 (LAMP1) nor syntaxin 17, which mediates autophagosome-lysosome fusion, to colocalize with LC3. These data indicate that necroptosis attenuates autophagic flux before the lysosome fusion step. Our findings may provide insights into human diseases involving necroptosis.

12.
Biochem Biophys Res Commun ; 523(2): 328-335, 2020 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-31864702

RESUMO

Intraepithelial lymphocytes (IELs) are very unique in the intestinal immune system. They include γδT cells and CD4-CD8-TCRαß+T cells (double negative: DNT), both of which are specific for the intestine, in addition to CD4+ and CD8+ T cells. IELs exist within the monolayer of the intestinal epithelial cells and dynamically move between lamina propria (LP) and intraepithelial (IE) region. The localization and movement patterns of IEL subsets and the regulatory factors have been unknown. Here, we developed a novel in vitro live imaging system and quantified the motility and morphological changes among subsets of IELs. We identified CD8αα as the key regulatory factor. IELs, especially γδ and DNT cells, showed amoeboid shape and frequent morphological change, while most T cells in MLN or SP showed round shape in vitro. TCR signal, IL-15, gut microbes, CCL25, and integrin αEß7 expression were non-essential for IEL movement in vitro. CD8αα+ cells showed higher motility and larger morphological changes than CD8αα- cells. Adoptive transferred CD8αα+CD4-IELs localized to IE region of recipient NSG mice, while CD8αα-CD4-IELs localized to the LP. Our results showed that the CD8αα/TL signal is essential for the localization of IELs to IE region in vivo. CD8αα/TL may be an effective target to increase the number of IELs, which protects against intestinal infection, allergy, tumorigenesis or inflammation.


Assuntos
Antígenos CD8/metabolismo , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos Intraepiteliais/citologia , Linfócitos Intraepiteliais/imunologia , Transferência Adotiva , Animais , Linfócitos T CD8-Positivos/classificação , Movimento Celular/imunologia , Forma Celular , Quimiocinas CC/metabolismo , Feminino , Imunidade nas Mucosas , Interleucina-15/metabolismo , Intestino Delgado/citologia , Intestino Delgado/imunologia , Linfócitos Intraepiteliais/classificação , Microscopia Intravital , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Camundongos Knockout , Camundongos SCID , Camundongos Transgênicos
13.
Nano Lett ; 20(1): 75-80, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31820649

RESUMO

Localized electronic spin state in molecules has a relatively long spin lifetime and has thus attracted much attention. In this study, we characterize the magnetoresistance of a system comprising Pt and Fe(II)-phthalocyanine (FePc) molecules. The magnetoresistance measurement with the weak antilocalization analysis reveals that a magnetic moment in FePc acts as magnetic impurities for conduction electrons in Pt. Moreover, we find that the magnetoresistance involves a component that possesses the same symmetry as spin-Hall magnetoresistance. These results reveal the spin-angular momentum transfer from metallic Pt to a magnetic moment in FePc molecules, which can be used as a spin torque in a molecular system.

14.
Biochem Biophys Res Commun ; 522(4): 971-977, 2020 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-31810607

RESUMO

In Japan and other Asian countries, increased fat uptake induced by a westernized diet is thought to be associated with an increased incidence of inflammatory bowel disease, colorectal cancer and food allergies; however, the mechanism for this remains unclear. High-fat diet (HFD)-fed mice are common animal models used to examine the effect of fat intake in vivo. HFDs are reported to exacerbate DSS-induced colitis and intestinal tumorigenesis, but the effect of HFDs on the intestines before disease induction is often overlooked. We found that the intestinal and gut-associated lymphoid tissue (GALT) morphology of HFD-fed mice differed from that of standard diet (SD)-fed mice. To clarify the mechanism by which fat intake increases intestinal diseases, we analyzed the morphological and immunological aspects of the intestines of HFD-fed mice as well as the molecular mechanisms and physiology. Feeding an HFD for 3 weeks induced atrophy of the small intestine, colon and GALT and reduced the number of small intestinal intraepithelial lymphocytes (IELs) and lamina propria lymphocytes (LPLs). Feeding an HFD for only one day reduced the number of small intestinal (SI)-IELs and SI-LPLs. The effect of feeding a 3-week HFD continued for 2 weeks after returning to the SD. The effect of the HFD on the intestinal immune system was independent of the gut microbes. We hypothesized that the cytotoxicity of the abundant HFD-derived free fatty acids in the intestinal lumen impairs the intestinal immune system. Both saturated and unsaturated free fatty acids were toxic to intestinal T-cells in vitro. Orally administering free fatty acids reduced the number of SI-IELs and LPLs. Using a lipase inhibitor to reduce the luminal free fatty acids attenuated the HFD-induced changes in the intestinal immune system, while using a statin to reduce the serum free fatty acids did not. Thus, HFD-induced free fatty acids damaged the intestines; this effect was termed "intestinal lipotoxicity". Because sustained reduction of SI-LPLs after HFD feeding exacerbated indomethacin-induced small intestinal damage, lipotoxicity to the human intestines incurred by consuming a westernized diet in Japan may increase intestinal diseases such as IBD, colorectal cancer or food allergies.


Assuntos
Dieta Hiperlipídica , Ácidos Graxos não Esterificados/toxicidade , Sistema Imunitário/patologia , Mucosa Intestinal/patologia , Animais , Atrofia , Colo/patologia , Ácidos Graxos não Esterificados/sangue , Comportamento Alimentar , Microbioma Gastrointestinal/efeitos dos fármacos , Sistema Imunitário/efeitos dos fármacos , Indometacina , Mucosa Intestinal/efeitos dos fármacos , Intestino Delgado/efeitos dos fármacos , Intestino Delgado/patologia , Contagem de Linfócitos , Linfócitos/efeitos dos fármacos , Tecido Linfoide/efeitos dos fármacos , Tecido Linfoide/patologia , Masculino , Camundongos Endogâmicos C57BL
15.
Clin Exp Pharmacol Physiol ; 47(2): 255-262, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31587341

RESUMO

Reduced serum cholesterol content was recently reported to be one of the factors responsible for cerebral haemorrhage. Stroke-prone spontaneously hypertensive rats (SHRSP) are known to have lower serum cholesterol content than normotensive Wistar-Kyoto rats (WKY). We previously reported that lower levels of mevalonate pyrophosphate decarboxylase (MPD) and squalene epoxidase (SQE), which are associated with cholesterol biosynthesis in the liver, are involved in the low serum cholesterol content in SHRSP. Here, we investigate the levels of sterol 14-demethylase (CYP51), methylsterol monooxygenase (SC4MOL), and hydroxysteroid 17-ß dehydrogenase 7 (HSD17B7), which contribute to the cholesterol synthesis pathway in the conversion of lanosterol to zymosterol, in SHRSP and WKY. The HSD17B7 mRNA levels in the liver of SHRSP were markedly lower than those in WKY, whereas no significant differences were observed in CYP51 and SC4MOL levels in the two types of rats. The relative levels of protein, heteronuclear RNA, and mRNA of HSD17B7 were also significantly lower in SHRSP than in WKY. The degradation rates of HSD17B7 were the same in SHRSP and WKY. The protein levels of HSD17B7 were not significantly reduced in tissues other than the liver, including the brain, lung, heart, spleen, kidney, and testis, in SHRSP. Moreover, HSD17B7 activity was significantly lower in SHRSP than in WKY. Thus, our results indicated that low protein levels and activity of HSD17B7 are responsible for the reduced cholesterol content in SHRSP, indicating that HSD17B7, along with MPD and SQE, is involved in the decreased cholesterol synthesis in the liver of SHRSP.

16.
J Invest Surg ; 33(10): 941-947, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31070068

RESUMO

Objectives: The microsurgical approach is considered the most reliable procedure in varicocelectomy. However, as there are difficulties in identifying the spermatic artery at the peripheral level, we had introduced intraoperative indocyanine green angiography (ICGA) for identification of arteries. In this study, we further investigated the usefulness of intraoperative ICGA in combination with an ordinary Doppler detector in microsurgical subinguinal varicocelectomy. Methods: A total of 140 men who underwent microsurgical subinguinal varicocelectomy at Gunma University Hospital were included. An operating microscope equipped with a near-infrared charge-coupled device was used for intraoperative ICGA. After exposing the vessels, arteries were identified using endoscopic vision only or with assistance of Doppler detector or ICGA, or of both. The number of preserved arteries was compared among the groups. Results: ICGA clearly visualized the internal spermatic arteries in all cases, allowing the surgeon to perform real-time identification and isolation of the spermatic artery intraoperatively. The use of ICGA or Doppler detector significantly increased the number of preserved arteries compared to the microscope-only operation from 1.11 to 1.75 (p < 0.05) and 1.57 (p < 0.05), respectively. The additional use of ICGA with Doppler detector further increased the number of preserved arteries to 2.41 (p < 0.05). Conclusions: Intraoperative ICGA facilitated safe and quick microsurgical subinguinal varicocelectomy by enabling visualization of thin spermatic cord blood vessels. Improved preservation of thin arteries, which is essential for patients with infertility, can be achieved with the combined use of ICGA and ordinary Doppler detector.

17.
Proc Biol Sci ; 286(1914): 20191571, 2019 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-31662089

RESUMO

Appendage patterning and evolution have been active areas of inquiry for the past two centuries. While most work has centred on the skeleton, particularly that of amniotes, the evolutionary origins and molecular underpinnings of the neuromuscular diversity of fish appendages have remained enigmatic. The fundamental pattern of segmentation in amniotes, for example, is that all muscle precursors and spinal nerves enter either the paired appendages or body wall at the same spinal level. The condition in finned vertebrates is not understood. To address this gap in knowledge, we investigated the development of muscles and nerves in unpaired and paired fins of skates and compared them to those of chain catsharks. During skate and shark embryogenesis, cell populations of muscle precursors and associated spinal nerves at the same axial level contribute to both appendages and body wall, perhaps representing an ancestral condition of gnathostome appendicular neuromuscular systems. Remarkably in skates, this neuromuscular bifurcation as well as colinear Hox expression extend posteriorly to pattern a broad paired fin domain. In addition, we identified migratory muscle precursors (MMPs), which are known to develop into paired appendage muscles with Pax3 and Lbx1 gene expression, in the dorsal fins of skates. Our results suggest that muscles of paired fins have evolved via redeployment of the genetic programme of MMPs that were already involved in dorsal fin development. Appendicular neuromuscular systems most likely have emerged as side branches of body wall neuromusculature and have been modified to adapt to distinct aquatic and terrestrial habitats.


Assuntos
Evolução Biológica , Extremidades , Músculos , Nadadeiras de Animais , Animais , Evolução Molecular , Peixes , Filogenia , Tubarões , Rajidae , Vertebrados
18.
ACS Appl Mater Interfaces ; 11(34): 31562-31572, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31373787

RESUMO

Multiferroic materials are strong candidates for reducing the energy consumption of voltage-controlled spintronic devices because of the coexistence of ferroelectric (FE) and magnetic orders in a single phase. In this article, we present a new multiferroic perovskite, GdNixFe1-xO3 (GFNO), produced via sputtering on a SrTiO3 substrate. The proposed GFNO is FE and canted antiferromagnetic (AFM) within a monoclinic framework at room temperature. The FE polarization of the GFNO is up to 37 µC/cm2. When capped with a Co layer, the resulting heterostructure exhibits voltage-controlled magnetism (VCM). The heterostructured device exhibits two distinct features. First, its VCM depends on the magnitude as well as the polarity of the applied bias, thereby doubling the number of available magnetic readout states under a fixed voltage. Furthermore, the magnetic order of the device can be controlled very effectively within ±1 V. These two characteristics satisfy the requirements for low-power and high-storage technology. Theoretical analysis and experimental results indicate the importance of Ni dopant in regulating the polarity-dependent multiferroicity of this gadolinium ferrite system.

19.
Inorg Chem ; 58(15): 10160-10166, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31294551

RESUMO

The ability to switch a molecule between different magnetic states is of considerable importance for the development of new molecular electronic devices. Desirable properties for such applications include a large-spin ground state with an electronic structure that can be controlled via external stimuli. Fe42 is a cyanide-bridged stellated cuboctahedron of mixed-valence Fe ions that exhibits an extraordinarily large S = 45 spin ground state. We have found that the spin ground state of Fe42 can be altered by controlling the humidity and temperature. Dehydration results in a 15 µB reduction of the saturation magnetization that can be partially recovered upon rehydration. The complementary use of UV-vis, IR, L2,3-edge X-ray absorption spectroscopy and X-ray magnetic circular dichroism is applied to uncover the mechanism for the observed dynamic behavior. It is identified that dehydration is concurrent with metal-to-metal electron transfer between Fe pairs via a cyanide π hybridization. Upon dehydration, electron transfer occurs from low-spin {FeII(Tp)(CN)3} sites to high-spin FeIII centers. The observed reduction in magnetization upon dehydration of Fe42 is inconsistent with a ferrimagnetic ground state and is proposed to originate from a change in zero-field splitting at electron-reduced high-spin sites.

20.
Int Heart J ; 60(4): 830-835, 2019 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-31257332

RESUMO

Uric acid is associated with cardiovascular disease (CVD) and its risk factors. Here, we examined the association between the serum uric acid level and incident metabolic syndrome in a Japanese general population. This retrospective, observational study was based on data obtained from an annual health checkup program in Gunma Prefecture, Japan. We evaluated 14,793 participants who did not use antihypertensive or antidiabetic medications and did not present with CVD or metabolic syndrome at the study baseline in 2009. Metabolic syndrome was defined as per the Japanese diagnostic criteria. A discrete proportional hazards regression model was used to evaluate the association between the serum uric acid level at baseline and the incident metabolic syndrome through 2012 and was adjusted for age, gender, waist circumference, systolic and diastolic blood pressure, fasting blood glucose, high-density lipoprotein cholesterol, and triglyceride. At baseline, the average age of the participants was 48.9 years, who were comprised of 40% women. The mean serum uric acid level at baseline was 5.3 ± 1.4 mg/dL. During the three-year follow-up, 7% of the cohort (n = 1,031) developed metabolic syndrome. The uric acid level was strongly associated with incident metabolic syndrome in the multivariable model (adjusted hazard ratio: 1.10; 95% confidence interval, 1.04-1.17; P < 0.01 per 1 mg/dL increase for uric acid). Higher uric acid levels were independently associated with a greater risk of incident metabolic syndrome in a Japanese general population.


Assuntos
Síndrome Metabólica/epidemiologia , Vigilância da População , Ácido Úrico/sangue , Biomarcadores/sangue , Feminino , Humanos , Incidência , Japão/epidemiologia , Masculino , Síndrome Metabólica/sangue , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco
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