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1.
Inorg Chem ; 62(23): 8940-8947, 2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-37261893

RESUMO

Based on the fundamental design concept of modulating the valence band maximum of oxides and subsequent predictions through computational approaches, several lone-pair ns2-based p-type oxide semiconductors, such as Sn2+- or Bi3+-based complex oxides, have been developed. Thus far, the bandgap can be modified via tuning of the chemical composition, whereas the hole density cannot be intentionally controlled because of the poor chemical stability of Sn2+ and/or the formation of oxygen vacancies. The inability to control hole density prohibits the design and realization of emergent electronic devices based on p- and n-type oxide semiconductors. Herein, we report the control of hole density via intentional chemical doping in polycrystalline Bi2WO6. While the holes of polycrystalline Nb- or Ta-doped Bi2WO6 are strongly trapped by grain boundaries, the hole density obtained at high temperatures monotonically increases with the increase in the doping concentration. This study provides important insights into the development of practical p-type oxide semiconductors.

2.
BMC Endocr Disord ; 23(1): 54, 2023 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-36879263

RESUMO

BACKGROUND: Cases of subacute thyroiditis (SAT) after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination have been reported. A human leukocyte antigen (HLA) allele, HLA-B*35, appears to be involved in the pathogenesis of SAT. CASE PRESENTATION: We conducted HLA typing of one patient with SAT and another with both SAT and Graves' disease (GD), which developed after SARS-CoV-2 vaccination. Patient 1, a 58-year-old Japanese man, was inoculated with a SARS-CoV-2 vaccine (BNT162b2; Pfizer, New York, NY, USA). He developed fever (38 °C), cervical pain, palpitations, and fatigue on day 10 after vaccination. Blood chemistry tests revealed thyrotoxicosis and elevated serum C-reactive protein (CRP) and slightly increased serum antithyroid-stimulating antibody (TSAb) levels. Thyroid ultrasonography revealed the characteristic findings of SAT. Patient 2, a 36-year-old Japanese woman, was inoculated twice with a SARS-CoV-2 vaccine (mRNA-1273; Moderna, Cambridge, MA, USA). She developed fever (37.8 °C) and thyroid gland pain on day 3 after the second vaccination. Blood chemistry tests revealed thyrotoxicosis and elevated serum CRP, TSAb, and antithyroid-stimulating hormone receptor antibody levels. Fever and thyroid gland pain persisted. Thyroid ultrasonography revealed the characteristic findings of SAT (i.e., slight swelling and a focal hypoechoic area with decreased blood flow). Prednisolone treatment was effective for SAT. However, thyrotoxicosis causing palpitations relapsed thereafter, for which thyroid scintigraphy with 99mtechnetium pertechnetate was conducted, and the patient was diagnosed with GD. Thiamazole treatment was then initiated, which led to improvement in symptoms. CONCLUSION: HLA typing revealed that both patients had the HLA-B*35:01, -C*04:01, and -DPB1*05:01 alleles. Only patient 2 had the HLA-DRB1*11:01 and HLA-DQB1*03:01 alleles. The HLA-B*35:01 and HLA-C*04:01 alleles appeared to be involved in the pathogenesis of SAT after SARS-CoV-2 vaccination, and the HLA-DRB1*11:01 and HLA-DQB1*03:01 alleles were speculated to be involved in the postvaccination pathogenesis of GD.


Assuntos
COVID-19 , Doença de Graves , Tireoidite Subaguda , Tireotoxicose , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Vacina BNT162 , Vacinas contra COVID-19/efeitos adversos , Teste de Histocompatibilidade , Cadeias HLA-DRB1 , SARS-CoV-2 , Tireoidite Subaguda/induzido quimicamente , Tireoidite Subaguda/diagnóstico , Tireoidite Subaguda/tratamento farmacológico , Vacinação
3.
Int J Mol Sci ; 22(1)2020 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-33383848

RESUMO

Obesity has become a global medical problem. The upregulation of senescence-related markers in adipose tissue may cause impairment of adipose tissue and disorders of systemic metabolism. Weight control through diet has been found to ameliorate senescence in the adipose tissue. Exercise is also important in maintaining a healthy lifestyle, however, very few researchers have examined the relationship between senescence-related markers in adipose tissue. Dietary restriction is also reported to have a legacy effect, wherein the effects are maintained for some periods after the termination of the intervention. However, very few researchers have examined the relationship between exercise and senescence-related markers in adipose tissue. Besides, there is no study on the long-term effects of exercise. Hence, we investigated whether the exercise could change the expression of senescence-related genes in the visceral adipose tissue of young mice and whether there was a legacy effect of exercise for 10 weeks after the termination of exercise. Four-week-old male ICR mice were assigned to one of the three groups: 20 weeks of sedentary condition, 20 weeks of voluntary wheel running exercise, or 10 weeks of exercise followed by 10 weeks of sedentary condition. The mice showed decreased expression in genes related to senescence and senescence-associated secretory phenotype, such as p53, p16, and IL-6, in the visceral adipose tissue in response to exercise. These effects were maintained for 10 weeks after the mice stopped exercising. Our study is the first report that exercise reduces the expression of senescence-related genes in the visceral adipose tissue of young mice, and that exercise causes the legacy effect.


Assuntos
Envelhecimento/genética , Biomarcadores , Regulação da Expressão Gênica , Gordura Intra-Abdominal/metabolismo , Condicionamento Físico Animal , Adipocinas/metabolismo , Animais , Biologia Computacional/métodos , Metabolismo Energético , Perfilação da Expressão Gênica , Ontologia Genética , Glucose/metabolismo , Masculino , Camundongos
4.
Phys Rev Lett ; 122(7): 071101, 2019 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-30848624

RESUMO

Gravity generated by large masses has been observed using a variety of probes from atomic interferometers to torsional balances. However, gravitational coupling between small masses has never been observed so far. Here, we demonstrate sensitive displacement sensing of the Brownian motion of an optically trapped 7 mg pendulum motion whose natural quality factor is increased to 10^{8} through dissipation dilution. The sensitivity for an integration time of one second corresponds to the displacement generated in a millimeter-scale gravitational experiment between the probe and a 100 mg source mass, whose position is modulated at the pendulum mechanical resonant frequency. Development of such a sensitive displacement sensor using a milligram-scale device will pave the way for a new class of experiments where gravitational coupling between small masses in quantum regimes can be achieved.

5.
Kyobu Geka ; 68(9): 777-9, 2015 Aug.
Artigo em Japonês | MEDLINE | ID: mdl-26329712

RESUMO

A 53-year-old woman was developed congestive heart failure. She was diagnosed as having aortic coarctation, incompetent bicuspid aortic valve and an aberrant right subclavian artery by using echocardiography and enhanced computed tomography. Ankle brachial pressure index(ABI)in the right was 0.71 and 0.69 in the left. Blood pressure of the right arm was 60 mmHg lower than that of the left arm. To avoid perioperative adverse cardiac events due to a 2-staged operation, we performed ascending-descending aortic bypass and aortic valve replacement simultaneously through a median sternotomy. The heart was retracted cranially, and a vascular prosthesis was anastomosed to the descending aorta just above the diaphragm in an end-to-side manner. Then the graft was placed curvilinearly around the right atrium and was anastomosed to the ascending aorta. After the operation, the right and left ABI increased to 0.90 and 0.98 respectively. There was no pressure difference between the arms. The postoperative course was uneventful.

6.
Small Methods ; : e2400863, 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39248659

RESUMO

For group 14 mono-elemental 2D materials, such as silicene, germanene, and stanene, oxidation is a severe problem that alters or degrades their physical properties. This study shows that the oxidized germanene on Ag(111)/Ge(111) can be reformed to germanene by simple heating ≈500 °C in a vacuum. The key reaction in reforming germanene is the desorption of GeO and GeO2 during heating ≈350 °C. After removing surface oxygen, Ge further segregates to the surface, resulting in the reformation of germanene. The reformed germanene has the same crystal structure, a (7√7 × 7√7) R19.1° supercell with respect to Ag(111), and has equivalent high quality to that of as-grown germanene on Ag(111)/Ge(111). Even after air oxidation, germanene can be reformed by annealing in a vacuum. On the other hand, the desorption of GeO and GeO2 at high temperatures is not suppressed in the O2 backfilling atmosphere. This instability of oxidized germanene/Ag(111)/Ge(111) at high temperatures contributes to the ease of germanene reformation without residual oxygen. In other words, the present germanene reformation, as well as the segregation of germanene on Ag(111)/Ge(111), is a highly robust process to synthesize germanene.

7.
Diabetes Res Clin Pract ; 215: 111799, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39084295

RESUMO

AIMS: Latent autoimmune diabetes in adults (LADA) is characterized by positive islet-associated autoantibodies including glutamic acid decarboxylase antibody (GADA), and gradual decline in insulin secretion, progressing to insulin dependency. This cross-sectional study aimed to determine whether GADA by enzyme-linked immunosorbent assay (GADA-ELISA) titer of ≥180 U/mL could be associated with decline in ß-cell function in participants with LADA. METHODS: Sixty-three participants with LADA were recruited and an association between insulin secretion capacity and disease duration was investigated. Insulin peptide-specific inflammatory immunoreactivity was investigated to determine the disease's activity. RESULTS: There was a significant inverse correlation between disease duration and C-peptide index in participants with GADA-ELISA titer of ≥180 U/mL (Spearman's r (rs) = -0.516, p < 0.01). The positivity rate of insulin peptide-specific inflammatory immunoreactivity was significantly higher in those with ≥180 U/mL than in those with <180 U/mL (p < 0.05). In participants with human leukocyte antigen (HLA)-DRB1*04:05, a significant inverse correlation was observed between disease duration and C-peptide index in those with ≥180 U/mL (rs = -0.751, p < 0.01). CONCLUSIONS: GADA-ELISA titer of ≥180 U/mL, especially with HLA-DRB1*04:05, might reflect higher disease activity and may be associated with decline in ß-cell function over time and future insulin dependency in LADA.


Assuntos
Autoanticorpos , Glutamato Descarboxilase , Células Secretoras de Insulina , Insulina , Diabetes Autoimune Latente em Adultos , Humanos , Glutamato Descarboxilase/imunologia , Masculino , Feminino , Estudos Transversais , Autoanticorpos/sangue , Adulto , Pessoa de Meia-Idade , Células Secretoras de Insulina/imunologia , Células Secretoras de Insulina/metabolismo , Diabetes Autoimune Latente em Adultos/imunologia , Diabetes Autoimune Latente em Adultos/sangue , Insulina/sangue , Peptídeo C/sangue , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/sangue , Cadeias HLA-DRB1/genética , Idoso
8.
J Med Case Rep ; 17(1): 114, 2023 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-36991521

RESUMO

BACKGROUND: Dentinogenic ghost cell tumor is a rare benign tumor that accounts for less than 3% of all cases and consists of the stellate reticulum, which is made up of enamel epithelioid and basaloid cells. Although DGCT is a benign tumor, the local infiltration of the odontogenic epithelium or recurrences have been reported, and its detailed pathology and treatments remain unclear. CASE PRESENTATION: This report describes the case of a 60-year-old Japanese male diagnosed with a maxillary dentinogenic ghost cell tumor. Images showed well-circumscribed, multilocular cystic lesions with a calcified substance in the interior. Marsupialization was performed along with biopsy to prevent the expansion of the lesion, and a partial maxillectomy was performed 2 years after the initial examination. Histopathological findings showed ameloblastomatous proliferation containing clusters of ghost cells and dentinoid materials, resulting in the diagnosis of dentinogenic ghost cell tumor. This article also reviews recently reported cases of dentinogenic ghost cell tumor. CONCLUSION: It is important to perform marsupialization, proper resection, and postoperative follow-up because of possible recurrence.


Assuntos
Ameloblastoma , Tumores Odontogênicos , Humanos , Masculino , Pessoa de Meia-Idade , Tumores Odontogênicos/diagnóstico por imagem , Tumores Odontogênicos/cirurgia , Maxila , Biópsia , Ameloblastoma/diagnóstico por imagem , Ameloblastoma/cirurgia , Diagnóstico Diferencial
9.
Intern Med ; 62(13): 1939-1946, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-36223925

RESUMO

We herein report two cases of early esophageal adenocarcinoma derived from non-Barrett's columnar epithelium. Both patients, a 65-year-old woman and 60-year-old man, had elevated lesions on white-light imaging. Magnifying endoscopy revealed slightly irregular surface and vessel patterns, and both patients were successfully treated with endoscopic submucosal dissection. Histopathologically, both lesions comprised of well-differentiated gastric mucin phenotype adenocarcinoma. One lesion was accompanied by ectopic gastric mucosa, but the other was speculated to be ectopic gastric mucosa according to the tumor locus at the upper thoracic esophagus. Despite its rarity, endoscopists should consider the existence of adenocarcinoma derived from non-Barrett's columnar epithelium.


Assuntos
Adenocarcinoma , Esôfago de Barrett , Neoplasias Esofágicas , Humanos , Esôfago de Barrett/complicações , Esôfago de Barrett/cirurgia , Esôfago de Barrett/patologia , Neoplasias Esofágicas/diagnóstico por imagem , Neoplasias Esofágicas/cirurgia , Neoplasias Esofágicas/complicações , Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/cirurgia , Adenocarcinoma/complicações , Epitélio/patologia
10.
J Cell Biochem ; 113(3): 808-14, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22021003

RESUMO

Smads 1/5/8 transduce the major intracellular signaling of bone morphogenetic proteins (BMPs). In the present study, we analyzed Smad1-binding proteins in HEK293T cells using a proteomic technique and identified the protein, zinc-finger, RAN-binding domain-containing protein 2 (ZRANB2). Zranb2 interacted strongly with Smad1, Smad5, and Smad8 and weakly with Smad4. The overexpression of Zranb2 inhibited BMP activities in C2C12 myoblasts in vitro, and the injection of Zranb2 mRNA into zebrafish embryos induced weak dorsalization. Deletion analyses of Zranb2 indicated that the serine/arginine-rich (SR) domain and the glutamine-rich domain were required for the inhibition of BMP activity and the interaction with Smad1, respectively. Zranb2 was found to be localized in the nucleus; however, the SR domain-deleted mutant localized to the cytoplasm. The knockdown of endogenous Zranb2 in C2C12 cells enhanced BMP activity. Zranb2 suppressed Smad transcriptional activity without affecting Smad phosphorylation, nuclear localization, or DNA binding. Taken together, these findings suggested that Zranb2 is a novel BMP suppressor that forms a complex with Smads in the nucleus.


Assuntos
Proteína Morfogenética Óssea 4/farmacologia , Proteínas de Ligação a RNA/metabolismo , Transdução de Sinais , Proteínas Smad/metabolismo , Sequência de Aminoácidos , Animais , Proteína Morfogenética Óssea 4/antagonistas & inibidores , Linhagem Celular , DNA/metabolismo , Humanos , Camundongos , Dados de Sequência Molecular , Estrutura Terciária de Proteína , Proteínas de Ligação a RNA/química , Proteínas Smad/antagonistas & inibidores , Transcrição Gênica
11.
J Clin Endocrinol Metab ; 107(5): e2124-e2132, 2022 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-34922394

RESUMO

CONTEXT: Unprovoked A-ß+ ketosis-prone type 2 diabetes (KPD) is characterized by the sudden onset of diabetic ketosis/ketoacidosis (DK/DKA) without precipitating factors, negative anti-islet autoantibodies ("A-"), and preservation of ß-cell function ("ß+") after recovery from DKA. Although this phenotype often appears with acute hyperglycemia and DK/DKA just like acute-onset type 1 diabetes (AT1D), the involvement of anti-islet immune responses remains unknown. OBJECTIVE: We sought to clarify the immunological role of insulin-associated molecules in unprovoked A-ß+ KPD. METHODS: In this cross-sectional study, blood samples from 75 participants (42 with AT1D and 33 with KPD) were evaluated for interferon (IFN)-γ-secreting peripheral blood mononuclear cells (PBMCs) reactive to 4 insulin B-chain amino acid 9-23-related peptides (B:9-23rPep) using an enzyme-linked immunospot (ELISpot) assay. RESULTS: Overall, 36.4% (12/33) of KPD participants showed positive IFN-γ ELISpot assay results; the positivity rate in KPD was similar to that in AT1D (38.1%; 16/42) and statistically significantly higher than the previously reported rate in type 2 diabetes (8%; 2/25; P < .0167). Moreover, B:9-23rPep-specific IFN-γ-producing PBMC frequency was negatively correlated with age and ad lib serum C-peptide levels in all KPD participants and positively correlated with glycated hemoglobin A1c level in KPD participants with positive IFN-γ ELISpot results. CONCLUSION: These findings suggest the involvement of B:9-23rPep-specific IFN-γ-related immunoreactivity in the pathophysiology of some unprovoked A-ß+ KPD. Moreover, increased immunoreactivity may reflect transiently decreased ß-cell function and increased disease activity at the onset of DK/DKA, thereby playing a key role in DK/DKA development in this KPD phenotype.


Assuntos
Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Cetoacidose Diabética , Cetose , Estudos Transversais , Humanos , Imunidade , Insulina , Interferon gama , Leucócitos Mononucleares
12.
Front Med (Lausanne) ; 9: 1092879, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36687430

RESUMO

Background: Invasive Klebsiella-associated liver abscesses can progress rapidly and cause severe metastatic infections such as meningitis and hydrocephalus, which are associated with high morbidity and mortality. In patients with large multiloculated liver abscesses after failure of percutaneous drainage, rapid diagnosis of the abscess followed by hepatic resection is necessary for early recovery and to prevent severe secondary metastatic complications. Case presentation: An 84-year-old woman with a large liver abscess and in septic shock was transferred to our hospital. Abdominal CT showed multiloculated liver abscesses 15 cm in diameter in the right lobe of the liver. We first performed percutaneous liver abscess drainage. The patient was managed in the intensive care unit, as well as treated with intravenous administration of meropenem followed by cefozopran according to the antibiogram. Klebsiella pneumoniae with invasive infection was confirmed by a string test in an isolated colony of K. pneumoniae; the K1 serotype with the rmpA and magA genes was determined by polymerase chain reaction and Sanger sequencing. Additional percutaneous liver abscess drainage was performed due to initial inadequate drainage. Although the abscess had shrunk to a diameter of 8 cm after drainage in 4 weeks, the patient recovered from sepsis, but still had low-grade fever (occasionally 38°C) and continued to have symptoms of chronic inflammation with persistent hyper mucus discharge from the liver abscess. Surgical resection was chosen to prevent prolonged hospitalization and ensure early recovery. A right posterior sectionectomy of the liver, including liver abscess, was performed. The post-operative course was uneventful, with no complications, and she was discharged after 18 days. There were no signs of abscess recurrence 1 year after surgery. Conclusion: We present a case of successful hepatic resection after percutaneous drainage failure in a patient with invasive K. pneumoniae multiloculated liver abscess.

13.
DEN Open ; 2(1): e76, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35310696

RESUMO

Immunoglobulin (Ig)G4-related disease (IgG4-RD) is a systemic condition associated with fibroinflammatory lesions and is characterized by elevated serum IgG4 levels and IgG4-positive cell infiltration into the affected tissues. It has been reported that IgG4-RD affects a variety of organs but uncommonly affects the gastrointestinal tract. In particular, there are few cases of lesions in the small intestine, except for sclerosing mesenteritis, which were mostly diagnosed from surgical specimens. Herein, we describe the case of a 70-year-old man who initially presented with abdominal pain, headache, later cognitive decline, and gait disturbance caused by IgG4-RD. Colonoscopy revealed irregular ulcers in the terminal ileum, and computed tomography of the head showed hypertrophic pachymeningitis. Numerous IgG4-positive cells were detected in the ileal and dural biopsies. We diagnosed the patient with IgG4-RD and started steroid pulse therapy. After initiation of treatment, the symptoms quickly improved. The patient was discharged from the hospital after starting oral prednisolone treatment (30 mg). The dosage was gradually reduced to 10 mg. A follow-up colonoscopy revealed scarring of the ileal ulcers. This case may provide valuable information regarding the endoscopic findings of small intestinal lesions in IgG4-RD.

14.
Ultrason Sonochem ; 71: 105354, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33053489

RESUMO

Ionic surfactants tend to accumulate in the interfacial region of ultrasonic cavitation bubbles (cavities) because of their surface active properties and because they are difficult to evaporate in cavitation bubbles owing to their extremely low volatilities. Hence, sonolysis of ionic surfactants is expected to occur in the interfacial region of the cavity. In this study, we performed sonochemical degradation of surfactants with different charge types: anionic, cationic, zwitterionic, and nonionic. We then estimated the degradation rates of the surfactants to clarify the surfactant behavior in the interfacial region of cavitation bubbles. For all of the surfactants investigated, the degradation rate increased with increasing initial bulk concentration and reached a maximum value. The initial bulk concentration to obtain the maximum degradation rate had a positive correlation with the critical micelle concentration (cmc). The initial bulk concentrations of the anionic surfactants were lower than their cmcs, while those of the cationic surfactants were higher than their cmcs. These results can be explained by the negatively charged cavity surface and the effect of the coexisting counterions of the surfactants.

15.
Materials (Basel) ; 14(8)2021 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-33919727

RESUMO

Poly(lactic acid)/hydroxyapatite (PLA/HAp) core-shell particles are prepared using the emulsification method. These particles are safe for living organisms because they are composed of biodegradable polymers and biocompatible ceramics. These particles are approximately 50-100 nm in size, and their hydrophobic substance loading can be controlled. Hence, PLA/HAp core-shell particles are expected to be used as drug delivery carriers for hydrophobic drugs. In this work, PLA/HAp core-shell particles with a loading of vitamin K1 were prepared, and their drug-loading ability was evaluated. The particles were 40-80 nm in diameter with a PLA core and a HAp shell. The particle size increased with an increase in the vitamin K1 loading. The drug-loading capacity (LC) value of the particles, an indicator of their drug-loading ability, was approximately 250%, which is higher than the previously reported values. The amount of vitamin K1 released from the particles increased as the pH of the soaking solution decreased because the HAp shell easily dissolved under the acidic conditions. The PLA/HAp particles prepared in this work were found to be promising candidates for drug delivery carriers because of their excellent drug-loading ability and pH sensitivity.

16.
Sci Rep ; 7(1): 14851, 2017 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-29093553

RESUMO

Surface enhanced Raman spectroscopy (SERS) is a novel method to sense molecular and lattice vibrations at a high sensitivity. Although nanostructured silver surface provides intense SERS signals, the silver surface is unstable under acidic environment and heated environment. Graphene, a single atomic carbon layer, has a prominent stability for chemical agents, and its honeycomb lattice completely prevents the penetration of small molecules. Here, we fabricated a SERS substrate by combining nanostructured silver surface and single-crystal monolayer graphene (G-SERS), and focused on its chemical stability. The G-SERS substrate showed SERS even in concentrated hydrochloric acid (35-37%) and heated air up to 400 °C, which is hardly obtainable by normal silver SERS substrates. The chemically stable G-SERS substrate posesses a practical and feasible application, and its high chemical stability provides a new type of SERS technique such as molecular detections at high temperatures or in extreme acidic conditions.

17.
Mol Brain ; 10(1): 2, 2017 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-28057021

RESUMO

Sleep-disordered breathing produces cognitive impairments, and is possibly associated with Alzheimer disease (AD). Intermittent hypoxia treatment (IHT), an experimental model for sleep-disordered breathing, results in cognitive impairments in animals via unknown mechanisms. Here, we exposed mice to IHT protocols, and performed biochemical analyses and microarray analyses regarding their hippocampal samples. In particular, we performed gene ontology (GO)-based microarray analysis to elucidate effects of IHT on hippocampal functioning, which were compared with the effects of various previously-reported experimental conditions on that (ref. Gene Expression Omnibus, The National Center for Biotechnology Information). Our microarray analyses revealed that IHT and aging shared alterations in some common GO, which were also observed with kainic acid treatment, Dicer ablation, or moderate glutamate excess. Mapping the altered genes using the Kyoto Encyclopedia of Genes and Genomes PATHWAY database indicated that IHT and aging affected several pathways including "MAPK signaling pathway", "PI3K-Akt signaling pathway", and "glutamatergic synapse". Consistent with the gene analyses, in vivo analyses revealed that IHT increased phosphorylated tau, reflecting an imbalance of kinases and/or phosphatases, and reduced proteins relevant to glutamatergic synapses. In addition, IHT increased phosphorylated p70 S6 kinase, indicating involvement of the mammalian target of rapamycin signaling pathway. Furthermore, IHT mice demonstrated hyperactivity in Y-maze tests, which was also observed in AD models. We obtained important data or something from the massive amount of microarray data, and confirmed the validity by in vivo analyses: the IHT-induced cognitive impairment may be partially explained by the fact that IHT increases phosphorylated tau via biological processes common to aging. Moreover, as aging is a major risk factor for AD, IHT is a novel model for investigating the pathological processes contributing to AD onset.


Assuntos
Envelhecimento/patologia , Hipocampo/metabolismo , Hipocampo/patologia , Hipóxia/metabolismo , Hipóxia/patologia , Proteínas tau/metabolismo , Animais , Ontologia Genética , Masculino , Aprendizagem em Labirinto , Camundongos Endogâmicos C57BL , Análise de Sequência com Séries de Oligonucleotídeos , Fosforilação , Análise de Componente Principal , Sinapses/metabolismo
18.
J Mater Chem B ; 4(41): 6640-6643, 2016 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-32263518

RESUMO

Protein-templated structured silica and titania are fabricated via a biomimetic method based on the synergistic effect of amine/carboxyl complexes under ambient conditions. Atelocollagen-templated silica showed a tangled fibrous structure with a smooth surface. The number of carboxyl groups of a protein is an important factor for homogeneous silica growth.

19.
ACS Nano ; 9(3): 3206-14, 2015 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-25738973

RESUMO

Manipulation of individual graphene sheets/films into specific architectures at macroscopic scales is crucially important for practical uses of graphene. We present herein a versatile and robust method based on annealing of solid carbon precursors on nickel templates and thermo-assisted removal of poly(methyl methacrylate) under low vacuum of ∼0.6 Pa for fabrication of macroscopic, freestanding, and tubular graphene (TG) architectures. Specifically, the TG architectures can be obtained as individual and woven tubes with a diameter of ∼50 µm, a wall thickness in the range of 2.1-2.9 nm, a density of ∼1.53 mg·cm(-3), a thermal stability up to 600 °C in air, an electrical conductivity of ∼1.48 × 10(6) S·m(-1), and field emission current densities on the order of 10(4) A·cm(-2) at low applied electrical fields of 0.6-0.7 V·µm(-1). These properties show great promise for applications in flexible and lightweight electronics, electron guns, or X-ray tube sources.

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