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1.
EMBO J ; 42(12): e111383, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37140455

RESUMO

Cancer exerts pleiotropic, systemic effects on organisms, leading to health deterioration and eventually to organismal death. How cancer induces systemic effects on remote organs and the organism itself still remains elusive. Here we describe a role for NetrinB (NetB), a protein with a particularly well-characterized role as a tissue-level axon guidance cue, in mediating oncogenic stress-induced organismal, metabolic reprogramming as a systemic humoral factor. In Drosophila, Ras-induced dysplastic cells upregulate and secrete NetB. Inhibition of either NetB from the transformed tissue or its receptor in the fat body suppresses oncogenic stress-induced organismal death. NetB from the dysplastic tissue remotely suppresses carnitine biosynthesis in the fat body, which is critical for acetyl-CoA generation and systemic metabolism. Supplementation of carnitine or acetyl-CoA ameliorates organismal health under oncogenic stress. This is the first identification, to our knowledge, of a role for the Netrin molecule, which has been studied extensively for its role within tissues, in humorally mediating systemic effects of local oncogenic stress on remote organs and organismal metabolism.


Assuntos
Proteínas de Drosophila , Drosophila , Animais , Drosophila/metabolismo , Netrinas/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Acetilcoenzima A/metabolismo , Transdução de Sinais , Axônios/metabolismo , Fatores de Crescimento Neural/metabolismo
2.
PLoS Biol ; 20(4): e3001586, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35468130

RESUMO

Many adult tissues are composed of differentiated cells and stem cells, each working in a coordinated manner to maintain tissue homeostasis during physiological cell turnover. Old differentiated cells are believed to typically die by apoptosis. Here, we discovered a previously uncharacterized, new phenomenon, which we name erebosis based on the ancient Greek word erebos ("complete darkness"), in the gut enterocytes of adult Drosophila. Cells that undergo erebosis lose cytoskeleton, cell adhesion, organelles and fluorescent proteins, but accumulate Angiotensin-converting enzyme (Ance). Their nuclei become flat and occasionally difficult to detect. Erebotic cells do not have characteristic features of apoptosis, necrosis, or autophagic cell death. Inhibition of apoptosis prevents neither the gut cell turnover nor erebosis. We hypothesize that erebosis is a cell death mechanism for the enterocyte flux to mediate tissue homeostasis in the gut.


Assuntos
Drosophila , Enterócitos , Animais , Apoptose , Morte Celular , Drosophila/metabolismo , Enterócitos/metabolismo , Homeostase
3.
Anal Chem ; 95(50): 18311-18315, 2023 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-38055789

RESUMO

We have developed a centrifugal gel-crushing method using a pipet tip. Polyacrylamide gel slices are extruded from the narrowing cavity of a pipet tip by centrifugation in a few minutes to crush them into pieces of appropriate size. The size of the crushed gel could be controlled by several parameters, including centrifugal force and pipet tip cavity. In shotgun proteomics, gel-based LC/MS/MS, so-called GeLC/MS/MS, involves the essential but tedious processes of prefractionation by SDS-PAGE, followed by dicing the entire gel lane into several parts, fine dicing, and in-gel digestion after the diced gel is manually transferred to a microtube. In this study, we developed an alternative way to crush the prefractionated gel slice into optionally small and irregular-shaped gels by centrifugal extrusion of the sliced gel from the narrow cavity of a pipet tip. As a result, we observed improved recovery and reproducibility of digested proteins compared to the conventional method of manual dicing. We believe that this simple and rapid method of crushing polyacrylamide gels, which allows for parallel operations and automation, is useful for GeLC/MS/MS analysis and applicable to other approaches, including top-down proteomics.


Assuntos
Proteoma , Espectrometria de Massas em Tandem , Proteoma/análise , Espectrometria de Massas em Tandem/métodos , Reprodutibilidade dos Testes , Eletroforese em Gel de Poliacrilamida , Géis
4.
Nucleic Acids Res ; 49(13): 7298-7317, 2021 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-34226921

RESUMO

Although ribosome-profiling and translation initiation sequencing (TI-seq) analyses have identified many noncanonical initiation codons, the precise detection of translation initiation sites (TISs) remains a challenge, mainly because of experimental artifacts of such analyses. Here, we describe a new method, TISCA (TIS detection by translation Complex Analysis), for the accurate identification of TISs. TISCA proved to be more reliable for TIS detection compared with existing tools, and it identified a substantial number of near-cognate codons in Kozak-like sequence contexts. Analysis of proteomics data revealed the presence of methionine at the NH2-terminus of most proteins derived from near-cognate initiation codons. Although eukaryotic initiation factor 2 (eIF2), eIF2A and eIF2D have previously been shown to contribute to translation initiation at near-cognate codons, we found that most noncanonical initiation events are most probably dependent on eIF2, consistent with the initial amino acid being methionine. Comprehensive identification of TISs by TISCA should facilitate characterization of the mechanism of noncanonical initiation.


Assuntos
Códon de Iniciação , Fator de Iniciação 2 em Eucariotos/metabolismo , Iniciação Traducional da Cadeia Peptídica , Biologia Computacional/métodos , Fator de Iniciação 3 em Eucariotos/metabolismo , Células HEK293 , Humanos , Fases de Leitura Aberta , Pegadas de Proteínas , Proteômica , Análise de Sequência de RNA
5.
Anal Chem ; 94(2): 944-951, 2022 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-34962382

RESUMO

We have developed a one-step method to isolate protein C-terminal peptides from V8 protease-digested proteins by metal oxide-based ligand-exchange (MOLEX) chromatography. V8 protease cleaves the C-terminal side of Asp and Glu, affording a digested peptide with two carboxy groups at the C-terminus, whereas the protein C-terminal peptide has only one α-carboxy group. In MOLEX chromatography, a stable chelate is formed between dicarboxylates and metal atoms, so that the nonterminal (i.e., internal) peptide is retained, whereas the protein C-terminal peptide flows through the MOLEX column. After the optimization of the MOLEX chromatographic conditions, 1619 protein C-termini were identified from 30 µg of peptides (10 µg each, in triplicate) derived from human HeLa cells by means of nanoLC/MS/MS. When the MOLEX-isolated sample from 200 µg of HeLa peptides was further divided into six fractions by high-pH reversed-phase liquid chromatography (LC) prior to nanoLC/MS/MS, 2203 protein C-termini were identified with less than 3% contamination with internal peptides. We believe that this is the largest coverage with the highest purity reported to date in human protein C-terminomics. This fast, simple, sensitive, and selective method to isolate protein C-terminal peptides should be useful for profiling protein C-termini on a proteome-wide scale.


Assuntos
Proteína C , Espectrometria de Massas em Tandem , Cromatografia de Fase Reversa , Células HeLa , Humanos , Ligantes , Óxidos , Peptídeo Hidrolases , Peptídeos/química , Espectrometria de Massas em Tandem/métodos
6.
Anal Chem ; 94(51): 18025-18033, 2022 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-36511577

RESUMO

Extracellular vesicles (EVs) are lipid bilayer vesicles that enclose various biomolecules. EVs hold promise as sensitive biomarkers to detect and monitor various diseases. However, they have heterogeneous molecular compositions. The compositions of EVs from identical donor cells obtained using the same purification methods may differ, which is a significant obstacle for elucidating objective biological functions. Herein, the potential of a novel lectin-based affinity chromatography (LAC) method to classify EVs based on their glycan structures is demonstrated. The proposed method utilizes a spongy-like monolithic polymer (spongy monolith, SPM), which consists of poly(ethylene-co-glycidyl methacrylate) with continuous micropores and allows an efficient in situ protein reaction with epoxy groups. Two distinct lectins with different specificities, Sambucus sieboldiana agglutinin and concanavalin A, are effectively immobilized on SPM without impacting the binding activity. Moreover, high recovery rates of liposomal nanoparticles as a model of EVs are achieved due to the large flow-through pores (>10 µm) of SPM compared to a typical agarose gel. Finally, lectin-immobilized SPMs are employed to classify EVs based on the surface glycan structures and demonstrate different subpopulations by proteome profiling. This is the first approach to clarify the variation of protein contents in EVs by the difference of surface glycans via lectin immobilized media.


Assuntos
Vesículas Extracelulares , Lectinas , Lectinas/metabolismo , Concanavalina A/química , Cromatografia de Afinidade/métodos , Vesículas Extracelulares/metabolismo , Polissacarídeos/metabolismo
7.
Int J Qual Health Care ; 34(1)2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35024823

RESUMO

BACKGROUND: Contrast media agents are essential for computed tomography (CT)-based diagnoses. However, they can cause fatal adverse effects such as anaphylaxis in patients. Although it is rare, the chances of anaphylaxis increase with the number of examinations. OBJECTIVE: We aimed to design a quality improvement initiative to reduce patient risk to contrast media agents. METHODS: We analysed CT processes using contrast iodine in a tertiary-care academic hospital that performs approximately 14 000 CT scans per year in Japan. We applied a combination of failure modes and effects analysis (FMEA) and cause-effect analysis to reduce the risk of patients developing allergic reactions to iodine-based contrast agents during CT imaging. RESULTS: Our multidisciplinary team comprising seven professionals analysed the data and designed a 56-process flowchart of CT imaging with iodine. We obtained 177 failure modes, of which 15 had a risk-probability number higher than 100. We identified the two riskiest processes and developed cause-and-effect diagrams for both: one was related to the exchange of information between the radiation and hospital information system regarding the patient's allergy, the other was due to education and structural deficiencies in observation following the exam. CONCLUSION: The combined method of FMEA and cause-and-effect analysis reveals high-risk processes and suggests measures to reduce these risks. FMEA is not well-known in healthcare but has significant potential for improving patient safety. Our findings emphasise the importance of adopting new techniques to reduce patient risk and carry out best practices in radiology.


Assuntos
Anafilaxia , Análise do Modo e do Efeito de Falhas na Assistência à Saúde , Anafilaxia/induzido quimicamente , Anafilaxia/prevenção & controle , Meios de Contraste/efeitos adversos , Humanos , Segurança do Paciente , Medição de Risco
8.
J Anesth ; 35(5): 671-709, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34338865

RESUMO

INTRODUCTION: Dr. Takuo Aoyagi invented pulse oximetry in 1974. Pulse oximeters are widely used worldwide, most recently making headlines during the COVID-19 pandemic. Dr. Aoyagi passed away on April 18, 2020, aware of the significance of his invention, but still actively searching for the theory that would take his invention to new heights. METHOD: Many people who knew Dr. Aoyagi, or knew of him and his invention, agreed to participate in this tribute to his work. The authors, from Japan and around the world, represent all aspects of the development of medical devices, including scientists and engineers, clinicians, academics, business people, and clinical practitioners. RESULTS: While the idea of pulse oximetry originated in Japan, device development lagged in Japan due to a lack of business, clinical, and academic interest. Awareness of the importance of anesthesia safety in the US, due to academic foresight and media attention, in combination with excellence in technological innovation, led to widespread use of pulse oximetry around the world. CONCLUSION: Dr. Aoyagi's final wish was to find a theory of pulse oximetry. We hope this tribute to him and his invention will inspire a new generation of scientists, clinicians, and related organizations to secure the foundation of the theory.


Assuntos
COVID-19 , Inventores , História do Século XX , História do Século XXI , Humanos , Japão , Oximetria , Pandemias , SARS-CoV-2
9.
Nutr Cancer ; 71(7): 1153-1164, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31179755

RESUMO

Many functional foods or physiologically active ingredients derived from plants and animals are actively being investigated for their role in chronic disease prevention. Squalene (SQ) is found as active ingredient in the functional foods predominantly present in olive oil and shark liver oil. It is known that during chemotherapy anticancer drugs induce inflammation. SQ has been thought to prevent and suppress inflammation; however, there is little direct evidence available. We examined the adjuvant effect of SQ on tumor-transplanted mice along with anticancer drug doxorubicin (DOX). SQ significantly suppressed the DOX-induced increase in prostaglandin E2 (PGE2) concentration (P < 0.05) in plasma of tumor-bearing mice. SQ inhibited the numbers of writhing response (P < 0.05), formalin-induced pain and decreased COX-2 and substance P expression in the tumor tissue compared to control mice and also enhanced the antitumor efficacy of DOX in allograft mice. Thus, SQ reduces inflammation through modulation of PGE2 production indicating its potential as an adjuvant during chemotherapy in tumor-bearing mice.


Assuntos
Analgésicos/farmacologia , Anti-Inflamatórios não Esteroides/farmacologia , Alimento Funcional , Esqualeno/farmacologia , Aloenxertos , Ração Animal , Animais , Linhagem Celular Tumoral , Neoplasias do Colo/tratamento farmacológico , Ciclo-Oxigenase 2/metabolismo , Inibidores de Ciclo-Oxigenase 2/farmacologia , Dinoprostona/sangue , Doxorrubicina/administração & dosagem , Camundongos Endogâmicos BALB C , Esqualeno/administração & dosagem , Substância P/metabolismo
10.
J Neurosci ; 37(10): 2723-2733, 2017 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-28167674

RESUMO

The ventral striatum is involved in motivated behavior. Akin to the dorsal striatum, the ventral striatum contains two parallel pathways: the striatomesencephalic pathway consisting of dopamine receptor Type 1-expressing medium spiny neurons (D1-MSNs) and the striatopallidal pathway consisting of D2-MSNs. These two genetically identified pathways are thought to encode opposing functions in motivated behavior. It has also been reported that D1/D2 genetic selectivity is not attributed to the anatomical discrimination of two pathways. We wanted to determine whether D1- and D2-MSNs in the ventral striatum functioned in an opposing manner as previous observations claimed, and whether D1/D2 selectivity corresponded to a functional segregation in motivated behavior of mice. To address this question, we focused on the lateral portion of ventral striatum as a region implicated in food-incentive, goal-directed behavior, and recorded D1 or D2-MSN activity by using a gene-encoded ratiometric Ca2+ indicator and by constructing a fiberphotometry system, and manipulated their activities via optogenetic inhibition during ongoing behaviors. We observed concurrent event-related compound Ca2+ elevations in ventrolateral D1- and D2-MSNs, especially at trial start cue-related and first lever press-related times. D1 or D2 selective optogenetic inhibition just after the trial start cue resulted in a reduction of goal-directed behavior, indicating a shared coding of motivated behavior by both populations at this time. Only D1-selective inhibition just after the first lever press resulted in the reduction of behavior, indicating D1-MSN-specific coding at that specific time. Our data did not support opposing encoding by both populations in food-incentive, goal-directed behavior.SIGNIFICANCE STATEMENT An opposing role of dopamine receptor Type 1 or Type 2-expressing medium spiny neurons (D1-MSNs or D2-MSNs) on striatum-mediated behaviors has been widely accepted. However, this idea has been questioned by recent reports. In the present study, we measured concurrent Ca2+ activity patterns of D1- and D2-MSNs in the ventrolateral striatum during food-incentive, goal-directed behavior in mice. According to Ca2+ activity patterns, we conducted timing-specific optogenetic inhibition of each type of MSN. We demonstrated that both D1- and D2-MSNs in the ventrolateral striatum commonly and positively encoded action initiation, whereas only D1-MSNs positively encoded sustained motivated behavior. These findings led us to reconsider the prevailing notion of a functional segregation of MSN activity in the ventral striatum.


Assuntos
Corpo Estriado/fisiologia , Comportamento Alimentar/fisiologia , Motivação/fisiologia , Neurônios/fisiologia , Receptores Dopaminérgicos/metabolismo , Recompensa , Animais , Comportamento Animal/fisiologia , Retroalimentação Psicológica/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Rede Nervosa/fisiologia
13.
Dev Biol ; 401(2): 206-19, 2015 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-25779703

RESUMO

Hematopoietic stem cells (HSCs) are present in hematopoietic organs and differentiate into mature blood cells as required. Defective HSCs have been implicated in the human autoimmune disease Tn syndrome, which results from the failure of the core 1 ß1,3-galactosyltransferase 1 enzyme (C1ß3GalT1) to synthesize T antigen. In both mice and humans, a reduced level of T antigen is associated with a reduction in blood cell numbers. However, the precise roles of T antigen in hematopoiesis are unknown. Here, we show that the Drosophila T antigen, supplied by plasmatocytes, is essential for the regulation of HSCs. T antigen appears to be an essential factor in maintaining the extracellular environment to support filopodial extensions from niches that are responsible for transmitting signaling molecules to maintain the HSCs. In addition, our results revealed that the clotting factor, hemolectin, disrupted the hemolymph environment of C1ß3GalT1 mutants. This study identified a novel mucin function for the regulation of HSCs that may be conserved in other species.


Assuntos
Antígenos Glicosídicos Associados a Tumores/metabolismo , Proteínas de Drosophila/genética , Galactosiltransferases/genética , Hematopoese/fisiologia , Células-Tronco Hematopoéticas/citologia , Pseudópodes/fisiologia , Animais , Animais Geneticamente Modificados , Drosophila melanogaster , Larva/metabolismo , Lectinas , Plasmócitos , Interferência de RNA , RNA Interferente Pequeno , Nicho de Células-Tronco
14.
J Stroke Cerebrovasc Dis ; 25(6): 1552-6, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27012218

RESUMO

We report a case of left upper cervical posterior spinal artery (PSA) syndrome caused by atherosclerosis of the left vertebral artery. A 70-year-old female experienced sudden dizziness and paralysis of the left upper and lower limbs. Diffusion-weighted magnetic resonance imaging (DWI) of the brain showed high signal intensity at the vermis and lower left hemisphere of the cerebellum, and magnetic resonance angiography showed that the entire left vertebral artery was thin. The patient was treated with an intravenous infusion of tissue plasminogen activator 2 hours after symptom onset and made a full recovery. Repeat DWI, fluid-attenuated inversion recovery images, and T2-weighted images showed high signal intensity in the left upper cervical PSA area from the lower medulla oblongata to the C2 level in addition to the cerebellum. Previously reported cases of cervical posterior artery syndrome are reviewed.


Assuntos
Aterosclerose/complicações , Vértebras Cervicais/irrigação sanguínea , Doenças Vasculares da Medula Espinal/etiologia , Artéria Vertebral/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Aterosclerose/diagnóstico , Aterosclerose/tratamento farmacológico , Aterosclerose/fisiopatologia , Imagem de Difusão por Ressonância Magnética , Feminino , Humanos , Infusões Intravenosas , Angiografia por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Inibidores da Agregação Plaquetária/uso terapêutico , Doenças Vasculares da Medula Espinal/diagnóstico por imagem , Doenças Vasculares da Medula Espinal/tratamento farmacológico , Doenças Vasculares da Medula Espinal/fisiopatologia , Terapia Trombolítica , Ativador de Plasminogênio Tecidual/administração & dosagem , Resultado do Tratamento , Artéria Vertebral/fisiopatologia , Adulto Jovem
15.
Int J Mol Sci ; 17(10)2016 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-27669218

RESUMO

Tocotrienol (T3), unsaturated vitamin E, is gaining a lot of attention owing to its potent anticancer effect, since its efficacy is much greater than that of tocopherol (Toc). Various factors are known to be involved in such antitumor action, including cell cycle arrest, apoptosis induction, antiangiogenesis, anti-metastasis, nuclear factor-κB suppression, and telomerase inhibition. Owing to a difference in the affinity of T3 and Toc for the α-tocopherol transfer protein, the bioavailability of orally ingested T3 is lower than that of Toc. Furthermore, cellular uptake of T3 is interrupted by coadministration of α-Toc in vitro and in vivo. Based on this, several studies are in progress to screen for molecules that can synergize with T3 in order to augment its potency. Combinations of T3 with chemotherapeutic drugs (e.g., statins, celecoxib, and gefitinib) or dietary components (e.g., polyphenols, sesamin, and ferulic acid) exhibit synergistic actions on cancer cell growth and signaling pathways. In this review, we summarize the current status of synergistic effects of T3 and an array of agents on cancer cells, and discuss their molecular mechanisms of action. These combination strategies would encourage further investigation and application in cancer prevention and therapy.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias/tratamento farmacológico , Tocotrienóis/uso terapêutico , Catequina/análogos & derivados , Catequina/uso terapêutico , Ácidos Cumáricos/uso terapêutico , Suplementos Nutricionais , Dioxóis/uso terapêutico , Sinergismo Farmacológico , Quimioterapia Combinada , Humanos , Lignanas/uso terapêutico , Neoplasias/prevenção & controle , Resveratrol , Estilbenos/uso terapêutico
16.
J Sci Food Agric ; 96(11): 3717-22, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26676315

RESUMO

BACKGROUND: Metabolic syndrome is a major risk factor for a variety of obesity-related diseases. Recently, the effects of functional foods have been investigated on lipid metabolism as a means to reduce lipid content in the blood, liver and adipose tissues associated with carnitine O-palmitoyltransferase (CPT) activity. Acanthopanax senticosus (Rupr. et Maxim) Harms (AS) is a medicinal herb possessing a wide spectra of functions including antioxidant, anti-inflammatory and anti-fatigue actions. Despite much research being focused on the cortical roots of AS, little information is available regarding its leaves, which are also expected to promote human health, for example by improving abnormal lipid metabolism. Here, we explored whether AS leaves affect lipid metabolism in mice fed a high-fat diet. RESULTS: The administration of AS to BALB/c mice fed a high-fat diet significantly decreased plasma triglycerides (TG). CPT activity in the liver of these mice was significantly enhanced by AS treatment. CONCLUSION: These findings indicate that AS leaves have the potential to alleviate increase in plasma TG levels due to high-fat diet intake in mice, possibly by increasing mitochondrial fatty acid ß-oxidation, especially via CPT activation. Consequently, daily intake of AS leaves could promote beneficial health effects including the prevention of metabolic syndrome. © 2015 Society of Chemical Industry.


Assuntos
Dieta Hiperlipídica , Eleutherococcus , Hiperlipidemias/metabolismo , Hipolipemiantes/farmacologia , Fígado/efeitos dos fármacos , Extratos Vegetais/farmacologia , Triglicerídeos/sangue , Animais , Carnitina O-Palmitoiltransferase/metabolismo , Hiperlipidemias/sangue , Hiperlipidemias/etiologia , Hiperlipidemias/prevenção & controle , Hipolipemiantes/uso terapêutico , Metabolismo dos Lipídeos , Fígado/metabolismo , Masculino , Camundongos Endogâmicos BALB C , Mitocôndrias/metabolismo , Fitoterapia , Extratos Vegetais/uso terapêutico , Folhas de Planta
17.
Biochem Biophys Res Commun ; 458(4): 920-7, 2015 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-25704087

RESUMO

In this study, we investigated cellular uptake and metabolism of phosphatidylcholine hydroperoxide (PCOOH) in human hepatoma HepG2 cells by high performance liquid chromatography-tandem mass spectrometry, and then evaluated whether PCOOH or its metabolites cause pathophysiological effects such as cytotoxicity and apoptosis. Although we found that most PCOOH was reduced to PC hydroxide in HepG2 cells, the remaining PCOOH caused cytotoxic effects that may be mediated through an unusual apoptosis pathway. These results will enhance our fundamental understanding of how PCOOH, which is present in oxidized low density lipoproteins, is involved in the development of atherosclerosis.


Assuntos
Apoptose , Células Hep G2/citologia , Fosfatidilcolinas/metabolismo , Ciclo Celular , Células Hep G2/metabolismo , Células Hep G2/patologia , Humanos , Potencial da Membrana Mitocondrial , Fosfatidilcolinas/toxicidade
18.
J Neurophysiol ; 111(8): 1601-14, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24478159

RESUMO

Although hippocampus is thought to perform various memory-related functions, little is known about the underlying dynamics of neural activity during a preparatory stage before a spatial choice. Here we focus on neural activity that reflects a memory-based code for spatial alternation, independent of current sensory and motor parameters. We recorded multiple single units and local field potentials in the stratum pyramidale of dorsal hippocampal area CA1 while rats performed a delayed spatial-alternation task. This task includes a 1-s fixation in a nose-poke port between selecting alternating reward sites and so provides time-locked enter-and-leave events. At the single-unit level, we concentrated on neurons that were specifically active during the 1-s fixation period, when the rat was ready and waiting for a cue to pursue the task. These neurons showed selective activity as a function of the alternation sequence. We observed a marked shift in the phase timing of the neuronal spikes relative to the theta oscillation, from the theta peak at the beginning of fixation to the theta trough at the end of fixation. The gamma-band local field potential also changed during the fixation period: the high-gamma power (60-90 Hz) decreased and the low-gamma power (30-45 Hz) increased toward the end. These two gamma components were observed at different phases of the ongoing theta oscillation. Taken together, our data suggest a switch in the type of information processing through the fixation period, from externally cued to internally generated.


Assuntos
Região CA1 Hipocampal/fisiologia , Comportamento de Escolha/fisiologia , Ritmo Gama/fisiologia , Células Piramidais/fisiologia , Ritmo Teta/fisiologia , Animais , Masculino , Memória/fisiologia , Ratos , Ratos Wistar
19.
Biochem Biophys Res Commun ; 453(3): 606-11, 2014 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-25285637

RESUMO

Rice bran consists of many functional compounds and thus much attention has been focused on the health benefits of its components. Here, we investigated the synergistic inhibitory effects of its components, particularly δ-tocotrienol (δ-T3) and ferulic acid (FA), against the proliferation of an array of cancer cells, including DU-145 (prostate cancer), MCF-7 (breast cancer), and PANC-1 (pancreatic cancer) cells. The combination of δ-T3 and FA markedly reduced cell proliferation relative to δ-T3 alone, and FA had no effect when used alone. Although δ-T3 induced G1 arrest by up-regulating p21 in PANC-1 cells, more cells accumulated in G1 phase with the combination of δ-T3 and FA. This synergistic effect was attributed to an increase in the cellular concentration of δ-T3 by FA. Our results suggest that the combination of δ-T3 and FA may present a new strategy for cancer prevention and therapy.


Assuntos
Proliferação de Células/efeitos dos fármacos , Ácidos Cumáricos/farmacologia , Neoplasias/patologia , Vitamina E/análogos & derivados , Linhagem Celular Tumoral , Sinergismo Farmacológico , Humanos , Reação em Cadeia da Polimerase em Tempo Real , Vitamina E/farmacologia
20.
Dermatol Surg ; 40(7): 756-62, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25111348

RESUMO

BACKGROUND: A new multisource phase-controlled radiofrequency (MPCRF) device is widely used for skin tightening and rejuvenation in Asia. OBJECTIVE: To evaluate the efficacy of MPCRF objectively and histologically. METHODS: An MPCRF device with real-time impedance control was evaluated. Ten Japanese patients were treated one side of the face, and the untreated side served as a control. Three-dimensional (3-D) imaging was performed to evaluate the posttreatment volume change. An independent observer assessed the 3-D images. Histologic evaluations of elastin were performed by Victoria Blue staining in 5 Japanese patients. RESULTS: Objective assessments evaluated by a 3-D color schematic representation showed improvement in skin laxity after the final treatment in all patients. The treated side improved markedly compared with the untreated side; however, even the untreated side slightly improved. The elastin density was significantly increased compared with controls in all 5 Japanese patients (p = .0013). Induced elastin appeared to be relatively thin elastic fibers without irregular elastic fibers, such as solar elastosis. Side effects were not observed, and the patients reported feeling comfortable throughout the study. CONCLUSION: Multisource phase-controlled radiofrequency treatments provide stimulation of elastin and skin-tightening results safely and effectively, and thus are beneficial for improving skin laxity and rhytides.


Assuntos
Técnicas Cosméticas , Elastina/análise , Imageamento Tridimensional , Terapia por Radiofrequência , Terapia por Ondas Curtas , Envelhecimento da Pele/efeitos da radiação , Adulto , Povo Asiático , Corantes , Elasticidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Compostos Orgânicos , Fotografação , Método Simples-Cego , Pele/química , Envelhecimento da Pele/patologia , Sulfassalazina
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