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1.
Cardiovasc Res ; 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38861679

RESUMO

AIMS: Specific cavins and caveolins, known as caveolae-related proteins, have been implicated in cardiac hypertrophy and myocardial injury. Cavin-2 forms complexes with other caveolae-related proteins, but the role of Cavin-2 in cardiomyocytes (CMs) is poorly understood. Here, we investigated an unknown function of Cavin-2 in CMs. METHODS AND RESULTS: Under cardiac stress-free conditions, systemic Cavin-2 knockout (KO) induced mild and significant CM hypertrophy. Cavin-2 KO suppressed phosphatase and tensin homolog (PTEN) associated with Akt signaling, whereas there was no difference in Akt activity between the hearts of the wild-type and the Cavin-2 KO mice under cardiac stress-free conditions. However, after swim training, CM hypertrophy was more facilitated with enhanced PI3K-Akt activity in the hearts of Cavin-2 KO mice. Cavin-2 knockdown neonatal rat CMs (NRCMs) using adenovirus expressing Cavin-2 shRNA were hypertrophied and resistant to hypoxia and H2O2-induced apoptosis. Cavin-2 knockdown increased Akt phosphorylation in NRCMs, and an Akt inhibitor inhibited Cavin-2 knockdown-induced anti-apoptotic responses in a dose-dependent manner. Cavin-2 knockdown increased PIP3 production and attenuated PTEN at the membrane fraction of NRCMs. Immunostaining and immunoprecipitation showed that Cavin-2 was associated with PTEN at the plasma membrane of NRCMs. A protein stability assay showed that Cavin-2 knockdown promoted PTEN destabilization in NRCMs. In an Angiotensin II (2-week continuous infusion)-induced pathological cardiac hypertrophy model, CM hypertrophy and CM apoptosis were suppressed in cardiomyocyte-specific Cavin-2 conditional KO (Cavin-2 cKO) mice. Because Cavin-2 cKO mouse hearts showed increased Akt activity but not decreased extracellular signal-regulated kinase activity, suppression of pathological hypertrophy by Cavin-2 loss may be due to increased survival of healthy CMs. CONCLUSIONS: Cavin-2 plays a negative regulator in the PI3K-Akt signaling in CMs through interaction with PTEN. Loss of Cavin-2 enhances Akt activity by promoting PTEN destabilization, which promotes physiological CM hypertrophy and may enhance Akt-mediated cardioprotective effects against pathological CM hypertrophy.

2.
Int J Colorectal Dis ; 39(1): 56, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38662090

RESUMO

PURPOSE: This study aimed to clarify the relationship between changes in elasticity and anorectal function before and after chemoradiotherapy. METHODS: This is a single-center prospective cohort study (Department of Surgical Oncology, The University of Tokyo). We established a technique to quantify internal anal sphincter hardness as elasticity using transanal ultrasonography with real-time tissue elastography. Twenty-seven patients with post-chemoradiotherapy rectal cancer during 2019-2022 were included. Real-time tissue elastography with transanal ultrasonography was performed before and after chemoradiotherapy to measure internal anal sphincter hardness as "elasticity" (hardest (0) to softest (255); decreased elasticity indicated sclerotic changes). The relationship between the increase or decrease in elasticity pre- and post-chemoradiotherapy and the maximum resting pressure, maximum squeeze pressure, and Wexner score were the outcome measures. RESULTS: A decrease in elasticity was observed in 16/27 (59.3%) patients after chemoradiotherapy. Patients with and without elasticity decrease after chemoradiotherapy comprised the internal anal sphincter sclerosis and non-sclerosis groups, respectively. The maximum resting pressure post-chemoradiotherapy was significantly high in the internal anal sphincter sclerosis group (63.0 mmHg vs. 47.0 mmHg), and a majority had a worsening Wexner score (60.0% vs. 18.2%) compared with that of the non-sclerosis group. Decreasing elasticity (internal anal sphincter sclerosis) correlated with a higher maximum resting pressure (r = 0.36); no correlation was observed between the degree of elasticity change and maximum squeeze pressure. CONCLUSION: Internal anal sphincter sclerosis due to chemoradiotherapy may correlate to anorectal dysfunction.


Assuntos
Canal Anal , Quimiorradioterapia , Técnicas de Imagem por Elasticidade , Neoplasias Retais , Humanos , Canal Anal/diagnóstico por imagem , Canal Anal/fisiopatologia , Masculino , Feminino , Pessoa de Meia-Idade , Quimiorradioterapia/efeitos adversos , Idoso , Neoplasias Retais/terapia , Neoplasias Retais/diagnóstico por imagem , Neoplasias Retais/fisiopatologia , Reto/fisiopatologia , Reto/diagnóstico por imagem , Elasticidade , Estudos Prospectivos , Adulto , Cuidados Pré-Operatórios , Pressão
3.
Commun Biol ; 7(1): 40, 2024 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-38182755

RESUMO

Caveolin-1 (CAV1) and Cavin-1 are components of caveolae, both of which interact with and influence the composition and stabilization of caveolae. CAV1 is associated with pulmonary arterial hypertension (PAH). Bone morphogenetic protein (BMP) type 2 receptor (BMPR2) is localized in caveolae associated with CAV1 and is commonly mutated in PAH. Here, we show that BMP/Smad signaling is suppressed in pulmonary microvascular endothelial cells of CAV1 knockout mice. Moreover, hypoxia enhances the CAV1/Cavin-1 interaction but attenuates the CAV1/BMPR2 interaction and BMPR2 membrane localization in pulmonary artery endothelial cells (PAECs). Both Cavin-1 and BMPR2 are associated with the CAV1 scaffolding domain. Cavin-1 decreases BMPR2 membrane localization by inhibiting the interaction of BMPR2 with CAV1 and reduces Smad signal transduction in PAECs. Furthermore, Cavin-1 knockdown is resistant to CAV1-induced pulmonary hypertension in vivo. We demonstrate that the Cavin-1/Caveolin-1 interaction attenuates BMP/Smad signaling and is a promising target for the treatment of PAH.


Assuntos
Caveolina 1 , Hipertensão Pulmonar , Proteínas de Membrana , Proteínas de Ligação a RNA , Transdução de Sinais , Animais , Camundongos , Caveolina 1/genética , Caveolina 1/metabolismo , Células Endoteliais , Camundongos Knockout , Hipertensão Arterial Pulmonar , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo
4.
J Am Chem Soc ; 145(35): 19177-19181, 2023 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-37623927

RESUMO

Multiple proton transfer (PT) controllable by external stimuli plays a crucial role in fundamental chemistry, biological activity, and material science. However, in crystalline systems, controlling multiple PT, which results in a distinct protonation state, remains challenging. In this study, we developed a novel tridentate ligand and iron(II) complex with a short hydrogen bond (HB) that exhibits a PT-coupled spin transition (PCST). Single-crystal X-ray and neutron diffraction measurements revealed that the positions of the two protons in the complex can be controlled by temperature and photoirradiation based on the thermal- and photoinduced PCST. The obtained results suggest that designing molecules that form short HBs is a promising approach for developing multiple PT systems in crystals.

5.
J Phys Chem A ; 127(25): 5344-5359, 2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37311020

RESUMO

Polyacetylene, the most representative synthetic conducting polymer, has attracted much attention because it exhibits high conductivity upon doping. In this paper, molecular structures, electronic excitation energies, and Raman and infrared spectra were calculated using density functional theory for trans- and cis-oligoenes with various chain lengths up to the number of C═C bonds (n) of 100 and trans- and cis-polyacetylenes under one-dimensional periodic boundary condition. The harmonic vibrational frequencies obtained at the B3LYP/6-311G(d,p) level were scaled by the scaling factors determined with respect to the anharmonic vibrational frequencies using the B2PLYP method, in which the coefficients of the functional were optimized for trans-oligoenes. The calculated infrared and Raman frequencies reproduce reasonably well the observed frequencies for trans- and cis-polyacetylene. Based on the chain-length dependence of the calculated Raman spectra of trans-oligoenes, we proposed the possibility of longer conjugated trans-segments observed in the resonance Raman spectra of trans-polyacetylene excited at longer wavelengths of 647.1 and 1064 nm. We also elucidated the origin of the excitation-wavelength dependence of the resonance Raman spectra of trans-polyacetylene and the structure of isomerization intermediates from cis-form to trans-form. In addition, the previous assignments of Raman and infrared spectra of trans- and cis-polyacetylene were reexamined in the present study based on the chain-length dependence of the spectra.

6.
Nat Commun ; 14(1): 3394, 2023 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-37296168

RESUMO

To alleviate the energy and environmental crisis, in the last decades, energy harvesting by utilizing optical control has emerged as a promising solution. Here we report a polar crystal that exhibits photoenergy conversion and energy storage upon light irradiation. The polar crystal consists of dinuclear [CoGa] molecules, which are oriented in a uniform direction inside the crystal lattice. Irradiation with green light induces a directional intramolecular electron transfer from the ligand to a low-spin CoIII centre, and the resultant light-induced high-spin CoII excited state is trapped at low temperature, realizing energy storage. Additionally, electric current release is observed during relaxation from the trapped light-induced metastable state to the ground state, because the intramolecular electron transfer in the relaxation process is accompanied with macroscopic polarization switching at the single-crystal level. It demonstrates that energy storage and conversion to electrical energy is realized in the [CoGa] crystals, which is different from typical polar pyroelectric compounds that exhibit the conversion of thermal energy into electricity.


Assuntos
Eletricidade , Temperatura Alta , Temperatura , Transporte de Elétrons , Temperatura Baixa
7.
Chem Commun (Camb) ; 59(57): 8850-8853, 2023 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-37368414

RESUMO

We demonstrate that the phenoxyl-imidazolyl radical complex (PIC), which is a rate-tunable fast photoswitch, can be used as a ligand that directly coordinates with iridium (III) ions. The iridium complexes show the characteristic photochromic reactions originating from the PIC moiety, whereas the behaviour of transient species is substantially different from that of the PIC.

8.
Sci Rep ; 13(1): 5924, 2023 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-37046036

RESUMO

Non-small cell lung cancer (NSCLC) is the leading cause of cancer-related mortality worldwide. Innovative treatment is required to improve overall survival rates for advanced NSCLC. Oncolytic virotherapy using enteroviruses has emerged as a promising anticancer strategy. To identify a novel, potent virotherapy with an improved safety profile, we assessed the oncolytic activity of 28 enteroviral strains and focused on coxsackievirus A11 (CVA11). CVA11 infection caused extensive oncolytic activity in all three of the examined human NSCLC cell lines, with high intercellular adhesion molecule-1 (ICAM-1) expression associated with greater CVA11-induced cytotoxicity. In vitro inhibition analysis using a pan-caspase inhibitor and western blot detection of cleaved poly (ADP-ribose) polymerase (PARP) indicated that apoptosis partly contributed to CVA11-driven cytotoxicity. CVA11 infection-induced immunogenic cell death in vitro was strongly suggested by substantial calreticulin expression and release of high mobility group box-1 protein (HMGB1). Moreover, in vivo treatment of human NSCLC xenografts with intratumoral CVA11 injection caused complete tumor regression in all treated mice, without significant weight loss. Our findings indicate that novel oncolytic virotherapy utilizing CVA11 may be less toxic and more effective than current treatments for human NSCLC, thus warranting further investigation in clinical trial settings, especially in combination with immunotherapy.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Enterovirus , Neoplasias Pulmonares , Terapia Viral Oncolítica , Vírus Oncolíticos , Humanos , Animais , Camundongos , Vírus Oncolíticos/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/patologia , Linhagem Celular Tumoral
9.
Colorectal Dis ; 25(3): 396-403, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36318592

RESUMO

AIM: Little is known about how ileal pouch-anal anastomosis (IPAA) influences anorectal manometric data. This study aimed to clarify temporal changes in anorectal manometric data and faecal incontinence in IPAA. METHODS: We examined 32 patients with ulcerative colitis (UC) or familial adenomatous polyposis (FAP) undergoing restorative proctocolectomy with stapled or hand-sewn IPAA. Maximum resting pressure (MRP) and maximum squeezing pressure (MSP) were analysed before and 1-3, 6-9, and 12-24 months after IPAA. Cleveland Clinic Florida-Faecal Incontinence Score (CCF-FIS) was measured 6-9 and 12-24 months after IPAA. RESULTS: Fourteen patients underwent stapled IPAA and 18 patients underwent hand-sewn IPAA. MRP decreased 1-3 months after stapled IPAA (median: 42.3 mmHg vs. 60.0 mmHg at preoperative value, p = 0.039), but recovered afterwards. In hand-sewn IPAA, the median MRP decreased to 29.5 mmHg at 1-3 months after IPAA (baseline: 64.8 mmHg, p < 0.0001), and remained unchanged thereafter. Stapled IPAA did not affect MSP; however, hand-sewn IPAA caused a reduction in the median MSP from 191.3 mmHg to 141.3 mmHg at 1-3 months (p = 0.035), which gradually increased afterwards. The median CCFFIS was 5.5 points at 6-9 months and 2 points at 12-24 months after stapled IPAA. The score was high (11 points) at 6-9 months but decreased to 5 points at 12-24 months after hand-sewn IPAA (p = 0.022). CONCLUSION: We present time trends in functional outcomes of IPAA. MRP showed a transient decrease after stapled IPAA, whereas it remained low after hand-sewn IPAA. CCFFIS was high only at 6-9 months after hand-sewn IPAA.


Assuntos
Polipose Adenomatosa do Colo , Colite Ulcerativa , Bolsas Cólicas , Incontinência Fecal , Proctocolectomia Restauradora , Humanos , Proctocolectomia Restauradora/efeitos adversos , Incontinência Fecal/etiologia , Incontinência Fecal/cirurgia , Colite Ulcerativa/cirurgia , Grampeamento Cirúrgico , Polipose Adenomatosa do Colo/cirurgia , Anastomose Cirúrgica , Resultado do Tratamento , Complicações Pós-Operatórias/cirurgia
10.
J Am Chem Soc ; 144(37): 17186-17197, 2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36070476

RESUMO

We propose a rational method for evaluating the diradical character of the photochromic phenoxyl-imidazolyl radical complex (PIC) derivatives based on their radical-radical coupling reaction rates. PIC consists of an imidazole ring, a phenoxyl ring, and a bridging unit that structurally connects them. The C-N bond formed between the imidazole and phenoxyl rings can be dissociated photochemically in a homolytic manner. The photochromism of PIC differs significantly from other photochromic molecules in that the transient colored open-ring isomer has a diradical character. The colored open-ring isomer returns promptly to the initial colorless closed-ring isomer by the intramolecular radical recombination reaction. By changing the aromaticity and substitution position of the bridging unit, it is possible to control the degree of contribution of the open-shell diradical and closed-shell quinoidal structures to the open-ring isomer. Systematic investigation of the photochromic reactions of several PIC derivatives revealed that the half-life of the open-ring isomers reflects the diradical character. Thus, the radical recombination reaction rate of the open-ring isomer of the PIC derivatives is an excellent parameter of the diradical character.

11.
Angew Chem Int Ed Engl ; 61(39): e202208771, 2022 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-35906869

RESUMO

Using light as a local heat source to induce a temporary pyroelectric current is widely recognized as an effective way to control the polarization of crystalline materials. In contrast, harnessing light directly to modulate the polarization of a crystal via excitation of the electronic bands remains less explored. In this study, we report an FeII spin crossover crystal that exhibits photoinduced macroscopic polarization change upon excitation by green light. When the excited crystal relaxes to the ground state, the corresponding pyroelectric current can be detected. An analysis of the structures, magnetic properties and the Mössbauer and infrared spectra of the complex, supported by calculations, revealed that the polarization change is dictated by the directional relative movement of ions during the spin transition process. The spin transition and polarization change occur simultaneously in response to light stimulus, which demonstrates the enormous potential of polar spin crossover systems in the field of optoelectronic materials.

12.
Int Heart J ; 63(2): 226-234, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35354744

RESUMO

The coronavirus disease 2019 pandemic occurred in several countries, making the conventional medical system difficult to maintain. Recent recommendations aim to prevent nosocomial infections and infections among health care workers. Therefore, establishing a cardiovascular medical system under an emergency for patients with ST-segment elevation myocardial infarction (STEMI) is desired. This study aimed to determine the relationship between prognosis and door-to-balloon time (DBT) shortening based on the severity on arrival.This retrospective, multi-center, observational study included 1,127 consecutive patients with STEMI. These patients were transported by emergency medical services and underwent primary percutaneous coronary intervention. Patients were stratified according to the Killip classification: Killip 1 (n = 738) and Killip ≥ 2 (n = 389) groups.Patients in the Killip ≥ 2 group were older, with more females, and more severity on arrival than those in the Killip 1 group. The 30-day mortality rate in the Killip 1 and Killip ≥ 2 groups was 2.2% and 18.0%, respectively. The Killip ≥ 2 group had a significant difference in the 30-day mortality between patients with DBT ≤ 90 minutes and those with DBT > 90 minutes; however, this did not occur in the Killip 1 group. Furthermore, multivariate analysis revealed that DBT ≤ 90 minutes was not a significant predictive factor in the Killip 1 group; however, it was an independent predictive factor in the Killip ≥ 2 group.DBT shortening affected the 30-day mortality in STEMI patients with Killip ≥ 2, although not those with Killip 1.


Assuntos
COVID-19 , Serviços Médicos de Emergência , Infarto do Miocárdio com Supradesnível do Segmento ST , Feminino , Humanos , Estudos Retrospectivos , Infarto do Miocárdio com Supradesnível do Segmento ST/cirurgia , Fatores de Tempo
13.
Phys Chem Chem Phys ; 24(3): 1685-1691, 2022 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-34982076

RESUMO

Anion-responsive photofunctional materials have been extensively studied because anions are important for biotic activity and constitute the building blocks of elegant supramolecular architectures. A number of fluorescent anion receptors that can probe anions in their environments have been reported, but the excited states of many of these molecules remain elusive. Studies on excited-state dynamics provide fruitful information for optimizing the emission properties, minimizing the photodegradation and photorelease of anions, and exploring novel photofunctions. In this study, we investigated the excited-state dynamics of an aryl-substituted dipyrrolyldiketone difluoroboron complex, a π-conjugated anion receptor, by time-resolved visible and infrared absorption spectroscopy and emission decay measurements combined with quantum chemical calculations. Anion binding was found to alter the radiative and nonradiative rate constants and the excited-state absorption of the anion receptor. In contrast, the molecular structures and binding abilities were similar in the S0 and S1 states.

14.
ESC Heart Fail ; 9(1): 428-441, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34854235

RESUMO

AIMS: Cardiac ischaemia/reperfusion (I/R) injury remains a critical issue in the therapeutic management of ischaemic heart failure. Although mild hypothermia has a protective effect on cardiac I/R injury, more rapid and safe methods that can obtain similar results to hypothermia therapy are required. 2-Methyl-2-thiazoline (2MT), an innate fear inducer, causes mild hypothermia resulting in resistance to critical hypoxia in cutaneous or cerebral I/R injury. The aim of this study is to demonstrate the protective effect of systemically administered 2MT on cardiac I/R injury and to elucidate the mechanism underlying this effect. METHODS AND RESULTS: A single subcutaneous injection of 2MT (50 mg/kg) was given prior to reperfusion of the I/R injured 10 week-old male mouse heart and its efficacy was evaluated 24 h after the ligation of the left anterior descending coronary artery. 2MT preserved left ventricular systolic function following I/R injury (ejection fraction, %: control 37.9 ± 6.7, 2MT 54.1 ± 6.4, P < 0.01). 2MT also decreased infarct size (infarct size/ischaemic area at risk, %: control 48.3 ± 12.1, 2MT 25.6 ± 4.2, P < 0.05) and serum cardiac troponin levels (ng/mL: control 8.9 ± 1.1, 2MT 1.9 ± 0.1, P < 0.01) after I/R. Moreover, 2MT reduced the oxidative stress-exposed area within the heart (%: control 25.3 ± 4.7, 2MT 10.8 ± 1.4, P < 0.01). These results were supported by microarray analysis of the mouse hearts. 2MT induced a transient, mild decrease in core body temperature (°C: -2.4 ± 1.4), which gradually recovered over several hours. Metabolome analysis of the mouse hearts suggested that 2MT minimized energy metabolism towards suppressing oxidative stress. Furthermore, 18F-fluorodeoxyglucose-positron emission tomography/computed tomography imaging revealed that 2MT reduced the activity of brown adipose tissue (standardized uptake value: control 24.3 ± 6.4, 2MT 18.4 ± 5.8, P < 0.05). 2MT also inhibited mitochondrial respiration and glycolysis in rat cardiomyoblasts. CONCLUSIONS: We identified the cardioprotective effect of systemically administered 2MT on cardiac I/R injury by sparing energy metabolism with reversible hypothermia. Our results highlight the potential of drug-induced hypothermia therapy as an adjunct to coronary intervention in severe ischaemic heart disease.


Assuntos
Hipotermia Induzida , Traumatismo por Reperfusão Miocárdica , Animais , Coração , Humanos , Hipotermia Induzida/métodos , Masculino , Camundongos , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Ratos , Tiazóis
15.
Mol Metab ; 55: 101416, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34896640

RESUMO

OBJECTIVE: Adipogenesis plays an essential role in maintaining energy and hormonal balance. Cavin-2, one of the caveolae-related proteins, is abundant in adipocytes, the leading site of adipogenesis. However, the details of the roles of Cavin-2 in adipogenesis remain unknown. Here, we demonstrate the requirement of Cavin-2 for the expression and stability of IRß in adequate adipocyte differentiation. METHODS: Cavin-2 knockout (Cavin-2 KO) and wild-type (WT) mice were fed with a high-fat diet (HFD) for 8 weeks. We evaluated body weight, food intake, and several tissues. Glucose homeostasis was assessed by glucose and insulin tolerance tests. Insulin signaling in epididymal white adipose tissue (eWAT) was determined by Akt phosphorylation. In vitro study, we evaluated adipocyte differentiation, adipogenesis-related genes, and insulin signaling to clarify the relationship between Cavin-2 and adipogenesis under the manipulation of Cavin-2 expression. RESULTS: Caveolae structure decreased in eWAT of Cavin-2 KO mice and Cavin-2 knockdown 3T3-L1 cells. Cavin-2 enhanced the stability of insulin receptor (IR) through direct association at the plasma membrane in adipocytes, resulting in accelerated insulin/IR/Akt signaling-induced adipogenic gene expression in insulin-containing solution-stimulated 3T3-L1 adipocytes. IR-mediated Akt activation also enhanced Cavin-2 and IR expression. Cavin-2 knockout mice showed insulin resistance with dyslipidemia and pathological hypertrophic adipocytes after a HFD. CONCLUSIONS: Cavin-2 enhances IR stability through binding IR and regulates insulin signaling, promoting adequate adipocyte differentiation. Our findings highlight the pivotal role of Cavin-2 in adipogenesis and lipid metabolism, which may help to develop novel therapies for pathological obesity and adipogenic disorders.


Assuntos
Adipócitos/metabolismo , Proteínas de Membrana/metabolismo , Receptor de Insulina/metabolismo , Células 3T3-L1 , Adipócitos/fisiologia , Adipogenia/genética , Tecido Adiposo Branco/metabolismo , Animais , Peso Corporal , Diferenciação Celular , Dieta Hiperlipídica , Glucose/metabolismo , Insulina/metabolismo , Resistência à Insulina , Metabolismo dos Lipídeos , Proteínas de Membrana/fisiologia , Camundongos , Obesidade/metabolismo , PPAR gama/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor de Insulina/fisiologia , Transdução de Sinais
16.
Nat Commun ; 12(1): 4836, 2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34376674

RESUMO

Pyroelectricity plays a crucial role in modern sensors and energy conversion devices. However, obtaining materials with large and nearly constant pyroelectric coefficients over a wide temperature range for practical uses remains a formidable challenge. Attempting to discover a solution to this obstacle, we combined molecular design of labile electronic structure with the crystal engineering of the molecular orientation in lattice. This combination results in electronic pyroelectricity of purely molecular origin. Here, we report a polar crystal of an [FeCo] dinuclear complex exhibiting a peculiar pyroelectric behavior (a substantial sharp pyroelectric current peak and an unusual continuous pyroelectric current at higher temperatures) which is caused by a combination of Fe spin crossover (SCO) and electron transfer between the high-spin Fe ion and redox-active ligand, namely valence tautomerism (VT). As a result, temperature dependence of the pyroelectric behavior reported here is opposite from conventional ferroelectrics and originates from a transition between three distinct electronic structures. The obtained pyroelectric coefficient is comparable to that of polyvinylidene difluoride at room temperature.

17.
Clin J Gastroenterol ; 14(5): 1426-1430, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34028785

RESUMO

The presence of extramural tumor deposits without lymph node structure (EX) is an important prognostic factor in patients with colorectal carcinoma. However, there is no English literature on neuroendocrine tumor (NET) with EX. We report a patient with rectal NET with extracapsular metastasis of a regional lymph node that was considered to be EX. A 51-year-old Japanese woman with diabetes was referred to our hospital for further examination of a submucosal tumor in the lower rectum. She was diagnosed as having rectal NET by immunohistochemical analysis of a biopsy, and underwent laparoscopic low anterior resection with lymph node dissection and covering ileostomy. Pathological findings of the resected specimen showed that the primary tumor was NET-G1 without any lymphatic or venous invasion. A single metastatic deposit was found near the capsule of a NET-negative regional lymph node. She has been free from recurrence for nine months without adjuvant treatments. Extracapsular metastasis of NET on a dissected lymph node in our case was considered to correspond to EX as defined for colorectal carcinoma. This rare case suggests that NET can disseminate to form EX in a similar manner to colorectal carcinoma.


Assuntos
Tumores Neuroendócrinos , Neoplasias Retais , Feminino , Humanos , Excisão de Linfonodo , Linfonodos/cirurgia , Metástase Linfática , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Tumores Neuroendócrinos/cirurgia , Prognóstico , Neoplasias Retais/cirurgia
18.
Chemphyschem ; 21(14): 1485, 2020 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-32672424

RESUMO

The front cover artwork is provided by the groups of Prof. Hiroshi Miyasaka (Osaka University, Japan), Prof. Masahiro Irie (Rikkyo University, Japan), Prof. Seiya Kobatake (Osaka City University, Japan) and Prof. Akira Sakamoto (Aoyama Gakuin University, Japan). The image shows the coherently vibrating closed form of a photochromic diarylethene derivative in the excited state, and subsequent structural evolution into the open form in the cycloreversion reaction. Read the full text of the Article at 10.1002/cphc.202000315.

19.
Chemphyschem ; 21(14): 1524-1530, 2020 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-32489017

RESUMO

The geometrical evolution of the reactant and formation of the photoproduct in the cycloreversion reaction of a diarylethene derivative were probed using time-resolved absorption spectroscopies in the visible to near-infrared and mid-infrared regions. The time-domain vibrational data in the visible region show that the initially formed Franck-Condon state is geometrically relaxed into the minimum in the excited state potential energy surface, concomitantly with the low-frequency coherent vibrations. Theoretical calculations indicate that the nuclear displacement in this coherent vibration is nearly parallel to that in the geometrical relaxation. Time-resolved mid-infrared spectroscopy directly detected the formation of the open-ring isomer with the same time constant as the decrease of the closed-ring isomer in the excited state minimum. This observation reveals that no detectable intermediate, in which the population is accumulated, is present between the excited closed-ring isomer and the open-ring isomer in the ground state.

20.
J Am Chem Soc ; 142(22): 10132-10142, 2020 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-32363867

RESUMO

Photochromic materials have been widely used in various research fields because of their variety of photoswitching properties based on various molecular frameworks and bond breaking processes, such as homolysis and heterolysis. However, while a number of photochromic molecular frameworks have been reported so far, there are few reports on photochromic molecular frameworks that show both homolysis and heterolysis depending on the substituents with high durability. The biradicals and zwitterions generated by homolysis and heterolysis have different physical and chemical properties and different potential applications. Therefore, the rational photochromic molecular design to control the bond dissociation in the excited state on demand expands the versatility for photoswitch materials beyond the conventional photochromic molecular frameworks. In this study, we synthesized novel photochromic molecules based on the framework of a radical-dissociation-type photochromic molecule: phenoxyl-imidazolyl radical complex (PIC). While the conventional PIC shows the photoinduced homolysis, the substitution of a strong electron-donating moiety to the phenoxyl moiety enables the bond dissociation process to be switched from homolysis to heterolysis. This study gives a strategy for controlling the bond dissociation process of the excited state of photochromic systems, and the strategy enables us to develop further novel radical and zwitterionic photoswitches.

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