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4.
Sci Rep ; 11(1): 6234, 2021 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-33737651

RESUMO

A brain atlas is necessary for analyzing structure and function in neuroimaging research. Although various annotation volumes (AVs) for the mouse brain have been proposed, it is common in magnetic resonance imaging (MRI) of the mouse brain that regions-of-interest (ROIs) for brain structures (nodes) are created arbitrarily according to each researcher's necessity, leading to inconsistent ROIs among studies. One reason for such a situation is the fact that earlier AVs were fixed, i.e. combination and division of nodes were not implemented. This report presents a pipeline for constructing a flexible annotation atlas (FAA) of the mouse brain by leveraging public resources of the Allen Institute for Brain Science on brain structure, gene expression, and axonal projection. A mere two-step procedure with user-specified, text-based information and Python codes constructs FAA with nodes which can be combined or divided objectively while maintaining anatomical hierarchy of brain structures. Four FAAs with total node count of 4, 101, 866, and 1381 were demonstrated. Unique characteristics of FAA realized analysis of resting-state functional connectivity (FC) across the anatomical hierarchy and among cortical layers, which were thin but large brain structures. FAA can improve the consistency of whole brain ROI definition among laboratories by fulfilling various requests from researchers with its flexibility and reproducibility.


Assuntos
Mapeamento Encefálico/métodos , Encéfalo/anatomia & histologia , Imageamento por Ressonância Magnética/métodos , Rede Nervosa/anatomia & histologia , Proteínas do Tecido Nervoso/genética , Neuroimagem/métodos , Animais , Atlas como Assunto , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Mapeamento Encefálico/normas , Expressão Gênica , Perfilação da Expressão Gênica , Imageamento por Ressonância Magnética/normas , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/metabolismo , Proteínas do Tecido Nervoso/classificação , Proteínas do Tecido Nervoso/metabolismo , Neuroimagem/normas , Vigília/fisiologia
5.
Biomaterials ; 209: 41-53, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31026610

RESUMO

Mesenchymal stromal/stem cell (MSC)-based therapy is a promising approach for the treatment of heart failure. However, current MSC-delivery methods result in poor donor cell engraftment, limiting the therapeutic efficacy. To address this issue, we introduce here a novel technique, epicardial placement of bi-layered, adhesive dressings incorporating MSCs (MSC-dressing), which can be easily fabricated from a fibrin sealant film and MSC suspension at the site of treatment. The inner layer of the MSC dressing, an MSC-fibrin complex, promptly and firmly adheres to the heart surface without sutures or extra glues. We revealed that fibrin improves the potential of integrated MSCs through amplifying their tissue-repair abilities and activating the Akt/PI3K self-protection pathway. Outer collagen-sheets protect the MSC-fibrin complex from abrasion by surrounding tissues and also facilitates easy handling. As such, the MSC-dressing technique not only improves initial retention and subsequent maintenance of donor MSCs but also augment MSC's reparative functions. As a result, this technique results in enhanced cardiac function recovery with improved myocardial tissue repair in a rat ischemic cardiomyopathy model, compared to the current method. Dose-dependent therapeutic effects by this therapy is also exhibited. This user-friendly, highly-effective bioengineering technique will contribute to future success of MSC-based therapy.


Assuntos
Insuficiência Cardíaca/terapia , Células-Tronco Mesenquimais/citologia , Animais , Bioengenharia/métodos , Western Blotting , Cardiomiopatias/metabolismo , Cardiomiopatias/patologia , Células Cultivadas , Feminino , Citometria de Fluxo , Humanos , Peróxido de Hidrogênio/farmacologia , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/efeitos dos fármacos , Miocárdio/citologia , Miocárdio/metabolismo , Gravidez , Ratos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Alicerces Teciduais
6.
Biomaterials ; 154: 12-23, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29117575

RESUMO

Transplantation of mesenchymal stromal cells (MSCs) is an emerging therapy for the treatment of heart failure. However, the delivery method of MSC is currently suboptimal. The use of self-assembling peptide hydrogels, including PuraMatrix® (PM; 3-D Matrix, Ltd), has been reported for clinical hemostasis and in research models. This study demonstrates the feasibility and efficacy of an advanced approach for MSC-therapy, that is coating of the epicardium with the instantly-produced PM hydrogel incorporating MSCs (epicardial PM-MSC therapy). We optimized the conditions/procedure to produce "instant" 2PM-MSC complexes. After spreading on the epicardium by easy pipetting, the PM-MSC complex promptly and stably adhere to the beating heart. Of note, this treatment achieved more extensive improvement of cardiac function, with greater initial retention and survival of donor MSCs, compared to intramyocardial MSC injection in rat heart failure models. This enhanced efficacy was underpinned by amplified myocardial upregulation of a group of tissue repair-related genes, which led to enhanced repair of the damaged myocardium, i.e. augmented microvascular formation and reduced interstitial fibrosis. These data suggest a potential for epicardial PM-MSC therapy to be a widely-adopted treatment of heart failure. This approach may also be useful for treating diseases in other organs than the heart.


Assuntos
Materiais Revestidos Biocompatíveis/farmacologia , Insuficiência Cardíaca/terapia , Hidrogel de Polietilenoglicol-Dimetacrilato/farmacologia , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Peptídeos/farmacologia , Pericárdio/metabolismo , Animais , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Insuficiência Cardíaca/fisiopatologia , Testes de Função Cardíaca , Concentração de Íons de Hidrogênio , Masculino , Células-Tronco Mesenquimais/metabolismo , Infarto do Miocárdio/terapia , Ratos Endogâmicos Lew , Ratos Sprague-Dawley
7.
Sci Rep ; 7(1): 6877, 2017 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-28761077

RESUMO

Recent research has shown that reparative (alternatively activated or M2) macrophages play a role in repair of damaged tissues, including the infarcted hearts. Administration of IL-4 is known to augment M2 macrophages. This translational study thus aimed to investigate whether IL-4 administration is useful for the treatment of myocardial infarction. Long-acting IL-4 complex (IL-4c; recombinant IL-4 mixed with anti-IL-4 monoclonal antibody as a stabilizer) was administered after coronary artery ligation in mice. It was observed that IL-4c administration increased accumulation of CD206+F4/80+ M2-like macrophages predominantly in the injured myocardium, compared to the control. Sorted cardiac M2-like macrophages highly expressed wide-ranging tissue repair-related genes. Indeed, IL-4c administration enhanced cardiac function in association with reduced infarct size and enhanced tissue repair (strengthened connective tissue formation, improved microvascular formation and attenuated cardiomyocyte hypertrophy). Experiments using Trib1 -/- mice that had a depleted ability to develop M2 macrophages and other in-vitro studies supported that these IL-4-mediated effects were induced via M2-like macrophages. On the other hand, when administered at Day 28 post-MI, the effects of IL-4c were diminished, suggesting a time-frame for IL-4 treatment to be effective. These data represent proof-of-concept of efficacy of IL-4 treatment for acute myocardial infarction, encouraging its further development.


Assuntos
Interleucina-4/uso terapêutico , Macrófagos/efeitos dos fármacos , Infarto do Miocárdio/tratamento farmacológico , Animais , Células Cultivadas , Interleucina-4/farmacologia , Peptídeos e Proteínas de Sinalização Intracelular/genética , Ativação de Macrófagos , Macrófagos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/genética
8.
Ecol Evol ; 5(19): 4221-32, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26664674

RESUMO

Changes in climate and anthropogenic pressures might affect the composition and abundance of forage fish in the world's oceans. The junk-food hypothesis posits that dietary shifts that affect the quality (e.g., energy content) of food available to marine predators may impact their physiological state and consequently affect their fitness. Previously, we experimentally validated that deposition of the adrenocortical hormone, corticosterone, in feathers is a sensitive measure of nutritional stress in seabirds. Here, we use this method to examine how changes in diet composition and prey quality affect the nutritional status of free-living rhinoceros auklets (Cerorhinca monocerata). Our study sites included the following: Teuri Is. Japan, Middleton Is. central Gulf of Alaska, and St. Lazaria Is. Southeast Alaska. In 2012 and 2013, we collected "bill loads" delivered by parents to feed their chicks (n = 758) to document dietary changes. We deployed time-depth-temperature recorders on breeding adults (n = 47) to evaluate whether changes in prey coincided with changes in foraging behavior. We measured concentrations of corticosterone in fledgling (n = 71) and adult breeders' (n = 82) feathers to determine how birds were affected by foraging conditions. We found that seasonal changes in diet composition occurred on each colony, adults dove deeper and engaged in longer foraging bouts when capturing larger prey and that chicks had higher concentrations of corticosterone in their feathers when adults brought back smaller and/or lower energy prey. Corticosterone levels in feathers of fledglings (grown during the breeding season) and those in feathers of adult breeders (grown during the postbreeding season) were positively correlated, indicating possible carryover effects. These results suggest that seabirds might experience increased levels of nutritional stress associated with moderate dietary changes and that physiological responses to changes in prey composition should be considered when evaluating the effect of prey quality on marine predators.

9.
Biol Lett ; 11(8)2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26311157

RESUMO

High levels of jellyfish biomass have been reported in marine ecosystems around the world, but understanding of their ecological role remains in its infancy. Jellyfish are generally thought to have indirect negative impacts on higher trophic-level predators, through changes in lower trophic pathways. However, high densities of jellyfish in the water column may affect the foraging behaviour of marine predators more directly, and the effects may not always be negative. Here, we present novel observations of a diving seabird, the thick-billed murre, feeding on fish aggregating among the long tentacles of large jellyfish, by using small video loggers attached to the birds. We show that the birds encountered large jellyfish, Chrysaora melanaster, during most of their dives, commonly fed on fish associated with jellyfish, and appeared to specifically target jellyfish with a high number of fish aggregating in their tentacles, suggesting the use of jellyfish may provide significant energetic benefits to foraging murres. We conclude that jellyfish provide feeding opportunities for diving seabirds by concentrating forage fish, and that the impacts of jellyfish on marine ecosystems are more complex than previously anticipated and may be beneficial to seabirds.


Assuntos
Charadriiformes/fisiologia , Comportamento Predatório , Cifozoários , Animais , Comportamento Alimentar
10.
Masui ; 64(2): 131-8, 2015 Feb.
Artigo em Japonês | MEDLINE | ID: mdl-26121803

RESUMO

BACKGROUND: We evaluated whether using thromboelastometry and tranexamic acid influenced blood loss and transfusion requirements in cardiac surgery requiring cardiopulmonary bypass. METHODS: We perfomed a retrospective analysis examining perioperative coagulation results, and the transfusion requirements of concentrated red cells (CRCs), fresh frozen plasma (FFP) and platelet administration between 12 months before and 10 months after thromboelastometry and tranexamic acid had been introduced in our institution. We also recorded patients' demographic details, the surgery performed and patient outcomes. RESULTS: After the introduction of thromboelastometry and tranexamic acid, fewer units of CRC were transfused during surgery, and fewer patients required postoperative CRC transfusion. Intra- and postoperative FFP requirements were also reduced. Intraoperative blood loss, blood loss in the first 24 hr after surgery, and length of hospital stay were also reduced. CONCLUSIONS: The use of ROTEM and tranexamic acid can potentially reduce blood loss and transfusion requirements in cardiac surgery.


Assuntos
Perda Sanguínea Cirúrgica/prevenção & controle , Procedimentos Cirúrgicos Cardíacos , Ponte Cardiopulmonar , Tromboelastografia , Ácido Tranexâmico/uso terapêutico , Idoso , Transfusão de Sangue , Feminino , Humanos , Masculino , Estudos Retrospectivos
11.
Nihon Hoshasen Gijutsu Gakkai Zasshi ; 70(12): 1455-62, 2014 Dec.
Artigo em Japonês | MEDLINE | ID: mdl-25672451

RESUMO

On X-ray diagnostic technology, it is important to grasp a change of the X-ray high-voltage equipment and radiographic technique factors. The 1st questionnaire was performed in 1974, and it carried out after that every five years, and conducted 8th investigation. As a result, we requested 656 institutions and got a reply from 103 institutions. The response rate was 15.7%. For X-ray high-voltage equipment, the inverter-type device shifts to 83.6% from 73.4% of last time. X-ray high-voltage equipment will be shifted to inverter-type device the near future. For X-ray tube device, the target angle becomes more smaller than usual, and maximum anode heat content is increasing tendency. The spread of digital devices is being advanced, and especially the flat panel detector (FPD) increases in the devices. The spread of soft copy diagnoses is 73.8% for chest image diagnoses, and 49.5% for breast image diagnosis. For the device management, the ratio of institutions measured at purchase time was 91.2%. But, the ratio of institutions performed an invariability examination was 58.4%. It is required to grasp the performance of an X-ray equipment and peripheral equipment, and to perform accuracy control in order to obtain proper radiographic technique factors and imaging. In order to use it for the improvement in photography technology, we would like to continue to conduct this investigation periodically.


Assuntos
Interpretação de Imagem Assistida por Computador/instrumentação , Intensificação de Imagem Radiográfica/instrumentação , Radiografia/instrumentação , Inquéritos e Questionários , Intensificação de Imagem Radiográfica/métodos , Intensificação de Imagem Radiográfica/tendências , Radiografia/tendências , Fatores de Tempo
12.
Masui ; 62(2): 186-9, 2013 Feb.
Artigo em Japonês | MEDLINE | ID: mdl-23479921

RESUMO

We present a case of postoperative convulsive seizure in an 84-year-old man who underwent an aortic valve replacement. The patient had hypertension associated with hyperaldosteronism and chronic interstitial nephritis. The duration of cardiopulmonary bypass was 74 min. A generalized seizure lasting approximately 1 minute occurred at 1 hour after the patient's arrival in the intensive care unit. A total of 9 generalized seizures, which were aborted by the intravenous administration of diazepam (5 mg), occurred every 30 min. For seizure control, the continuous administration of midazolam (2 mg x hr(-1)) was initiated. On the day after the discontinuation of the midazolam, a generalized seizure recurred and an infusion of sodium thiopental was started. No further seizures were observed. On the sixth postoperative day, the patient was extubated and discharged without any neurological abnormalities. Imaging showed old small areas of cerebral infarction in the basal ganglia, which were not thought to have contributed to the seizures. The blood sugar, sodium, and calcium levels were within the normal limits. The seizures were likely due to a total dose of 8 g of tranexamic acid (TXA) administered intraoperatively. Possible mechanisms of TXA-induced seizures include blockage of inhibitory cortical y -aminobutyric acid-A receptors.


Assuntos
Valva Aórtica/cirurgia , Convulsões/induzido quimicamente , Ácido Tranexâmico/efeitos adversos , Idoso de 80 Anos ou mais , Humanos , Masculino , Complicações Pós-Operatórias , Ácido Tranexâmico/administração & dosagem
13.
Rev Sci Instrum ; 80(6): 064902, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19566219

RESUMO

Some disorders such as circulatory disease and metabolic abnormality cause many problems to peripheral blood flow condition. Therefore, frequent measurement of the blood flow condition is bound to contribute to precaution against those disorders and to control of conditions of the diseases. We propose a convenient means of blood flow volume measurement at peripheral part, such as fingertips. Principle of this measurement is based on heat transfer characteristics of peripheral part containing the blood flow. Transition response analysis of skin surface temperature has provided measurement model of the peripheral blood flow volume. We developed the blood flow measurement system based on that model and evaluated it by using artificial finger under various temperature conditions of ambience and internal fluid. The evaluation results indicated that proposed method could estimate the volume of the fluid regardless of temperature condition of them. Finally we applied our system to real finger testing and have obtained results correlated well with laser Doppler blood flow meter values.


Assuntos
Dedos/irrigação sanguínea , Monitorização Fisiológica , Fluxo Sanguíneo Regional , Algoritmos , Desenho de Equipamento , Feminino , Humanos , Fluxometria por Laser-Doppler , Masculino , Modelos Biológicos , Monitorização Fisiológica/instrumentação , Monitorização Fisiológica/métodos , Temperatura Cutânea , Temperatura , Termômetros
14.
J Am Chem Soc ; 129(19): 6180-6, 2007 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-17444642

RESUMO

There have been recent advances in the ribosomal synthesis of various molecules composed of nonnatural ribosomal substrates. However, the ribosome has strict limitations on substrates with elongated backbones. Here, we show an unexpected loophole in the E. coli translation system, based on a remarkable disparity in its selectivity for beta-amino/hydroxy acids. We challenged beta-hydroxypropionic acid (beta-HPA), which is less nucleophilic than beta-amino acids but free from protonation, to produce a new repertoire of ribosome-compatible but main-chain-elongated substrates. PAGE analysis and mass-coupled S-tag assays of amber suppression experiments using yeast suppressor tRNAPheCUA confirmed the actual incorporation of beta-HPA into proteins/oligopeptides. We investigated the side-chain effects of beta-HPA and found that the side chain at position alpha and R stereochemistry of the beta-substrate is preferred and even notably enhances the efficiency of incorporation as compared to the parent substrate. These results indicate that the E. coli translation machinery can utilize main-chain-elongated substrates if the pKa of the substrate is appropriately chosen.


Assuntos
Aminoácidos/química , Escherichia coli/metabolismo , Ácido Láctico/análogos & derivados , Oligopeptídeos/biossíntese , Biossíntese de Proteínas , Aminoacil-RNA de Transferência/metabolismo , Western Blotting , Eletroforese em Gel de Poliacrilamida , Escherichia coli/genética , Ésteres , Ácido Láctico/química , RNA Bacteriano/metabolismo , Ribossomos/metabolismo , Especificidade por Substrato
15.
Nucleic Acids Symp Ser (Oxf) ; (50): 37-8, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17150805

RESUMO

The ribosome catalyzes oligo/polymerization of amino acids. We designed an allowable modification of amino acid backbone, based on the hypothesized mechanism of peptidyl transfer reaction. Nonsense suppression method was used to investigate the acceptability of these substrates in the prokaryotic ribosomal system. The E.coli ribosome showed a restricted tolerance to the backbone modification, especially for main-chain elongation. However, our designed homologous beta-hydroxyalkanoic acid with elongated methylene (backbone) chain-length was revealed to be a possible substrate for the E.coli ribosome.


Assuntos
Códon , Escherichia coli/genética , Biossíntese de Proteínas , Engenharia de Proteínas/métodos , Ribossomos/metabolismo , Propionatos/metabolismo
16.
J Am Chem Soc ; 127(22): 7998-9, 2005 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-15926808

RESUMO

In the presence of the stable sulfamoyl analogue of phenylalanyl adenylate (Phe-SA), the UUU/UUC sense codon for phenylalanine (Phe) can be silenced and reassigned to a naphthylalanine (Nap) conjugated to tRNAPhe. We have demonstrated the efficiency and selectivity or orthogonality of the Phe-to-Nap reassignment induced by an "orthogonal reacylation stalling" strategy at the single-codon level in the translation of mRNAs of dihydrofolate reductase and a 24-mer oligopeptide. We used a prokaryotic translation system with an essential preincubation, during which the endogenous precharged phenylalanyl-tRNAPhe undergoes deacylation and the reacylation of the resulting tRNAPhe is stalled by the action of Phe-SA to inhibit the phenylalanyl-tRNA synthetase activity. We discuss the significance of the present small-molecule-based approach to sense-codon templated natural-unnatural peptides.


Assuntos
Alanina/análogos & derivados , Códon/química , Oligopeptídeos/síntese química , Aminoacil-RNA de Transferência/química , Acilação , Adenosina/análogos & derivados , Alanina/química , Alanina/genética , Sequência de Aminoácidos , Códon/genética , Códon/metabolismo , Escherichia coli/enzimologia , Escherichia coli/genética , Inativação Gênica , Dados de Sequência Molecular , Oligopeptídeos/biossíntese , Oligopeptídeos/genética , Fenilalanina/química , Fenilalanina/genética , Fenilalanina/metabolismo , Fenilalanina-tRNA Ligase/antagonistas & inibidores , Fenilalanina-tRNA Ligase/metabolismo , RNA Mensageiro/síntese química , RNA Mensageiro/genética , Aminoacil-RNA de Transferência/genética , Aminoacil-RNA de Transferência/metabolismo , Tetra-Hidrofolato Desidrogenase/biossíntese , Tetra-Hidrofolato Desidrogenase/genética
17.
Nucleic Acids Symp Ser (Oxf) ; (49): 273-4, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-17150739

RESUMO

Nonsense suppression method was used to probe the allowable modification of substrate (amino acid) backbone in the prokaryotic ribosomal system. Dihydrofolate reductase (DHFR) with an amber mutation was translated in the RF1-diminished prokaryotic cell free translation system in the presence of chemically-misacylated yeast tRNA(Phe)CUA. The prokaryotic ribosome showed a restricted tolerance to the backbone modification. Although natural-type alpha-amino acid was accepted as a good substrate for the ribosome, incorporation of beta-aminopropionic acid was not detected under our experimental conditions. Interestingly, we found that the homologous beta-hydroxyalkanoic acid with elongated methylene (backbone) chain-length can be a substrate for the ribosome, giving an important implication for the chemical mechanism of the ribosome-catalyzed peptide bond forming reaction.


Assuntos
Oligopeptídeos/biossíntese , Biossíntese de Proteínas , Ribossomos/metabolismo , Sequência de Bases , Catálise , Dados de Sequência Molecular , Mutação , Oligopeptídeos/química , Propionatos/química , Proteínas/química , RNA Mensageiro/química , RNA de Transferência de Fenilalanina/química , Moldes Genéticos , Tetra-Hidrofolato Desidrogenase/biossíntese , Tetra-Hidrofolato Desidrogenase/genética
18.
Bioorg Med Chem Lett ; 13(16): 2633-6, 2003 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-12873482

RESUMO

We report here that unprotected carbohydrates (maltose, lactose, cellobiose, and maltoheptaose) can be attached to the aminoalkylated oligonucleotides under mild reductive-amination conditions (aqueous borate buffer, pH 8.0, NaBH(3)CN, 60 degrees C) without notable side reactions. Quadruplex-forming G-rich oligonucleotide, 5'-aminoalkyl d(TGGGGT), is glycosylated with maltoheptaose to afford a novel DNA-assisted tetrasaccharide cluster motif.


Assuntos
Carboidratos/química , DNA/química , Oligonucleotídeos/síntese química , Alquilação , Aminação , Boroidretos/química , Carboidratos/síntese química , Cromatografia Líquida de Alta Pressão , Dicroísmo Circular , DNA/síntese química , Quadruplex G , Glucanos/química , Glicosilação , Modelos Químicos , Oxirredução
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