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1.
Phytochem Anal ; 35(5): 1197-1206, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38572825

RESUMO

INTRODUCTION: Sicklepod [Cassia obtusifolia L. syn Senna obtusifolia (L.) H.S. Irwin & Barneby, Fabaceae] sprouts are promising ingredients with health-promoting benefits. Notwithstanding, the pharmacologically active compounds in sicklepod sprouts have not been studied or analysed in detail. OBJECTIVE: This study aimed to isolate and structurally identify phytochemicals showing α-glucosidase inhibitory activity in sicklepod sprouts and simultaneously quantify the compounds in the sprouts to determine the optimal cultivation method and germination time to maximise active compounds. METHOD: A simultaneous high-performance liquid chromatography-ultraviolet (HPLC-UV) method with high sensitivity and accuracy was developed and used to analyse time-dependent changes in anthraquinone content during sicklepod germination. RESULTS: Thirteen anthraquinones were isolated and identified, of which six-chrysoobtusin, emodin, 1-O-methyl-2-methoxychrysophanol, 7-O-methylobtusin, chrysophanol, and physcion-showed moderate α-glucosidase inhibitory activity. The maximum content of anthraquinones in a sprout was observed on Day 5 under both light and dark conditions. CONCLUSION: The findings of this study revealed that sicklepod sprouts which are promising functional food materials contain a variety of anthraquinones.


Assuntos
Antraquinonas , Inibidores de Glicosídeo Hidrolases , alfa-Glucosidases , Antraquinonas/farmacologia , Inibidores de Glicosídeo Hidrolases/farmacologia , Cromatografia Líquida de Alta Pressão/métodos , alfa-Glucosidases/metabolismo , Cassia/química , Senna/química , Germinação/efeitos dos fármacos
2.
Childs Nerv Syst ; 38(9): 1803-1807, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35083514

RESUMO

The purpose of treatment for unilocular intracranial cysts (UICs) is to release elevated intracranial pressure. Neuroendoscopic fenestration (NF) is one of the most effective and minimally invasive options for treating UICs, especially in young children; however, the optimal location and number of fenestrations, the necessity of using endoscopic third ventriculostomy (ETV) in combination with fenestration, and the course of treatment are not well known. We retrospectively reviewed the hospital records between 2012 and 2019. The patients were studied in terms of sex, age at surgery, preoperative symptoms, cyst localization and size, course of treatment, ventricular diameter, developmental assessment, anatomical location, and the number of fenestrations. There were four eligible patients in the relevant period: two boys and two girls. The median age at the time of surgery was 16 months. With regard to the location of the cysts, there were two cases of cavum velum interpositum (CVI), one case of quadrigeminal cistern, and one case of an isolated lateral ventricle. The most common preoperative finding was an enlarged head circumference. All the patients were treated with NF, including one case of reoperation after open head surgery. Postoperatively, we used the frontal and occipital horn ratio (FOHR) to evaluate the ventricular size. The average reduction in the FOHR was 0.003. In the most recent developmental assessment or examination during the follow-up period, two patients showed normal development, and two patients showed developmental delay. Based on our past experience and reports, we believe that it is recommended to perform two fenestrations for a single cyst. This is because it creates a flow of cerebrospinal fluid (CSF) within the cyst into normal CSF reflux. For lesions with obstruction of the aqueduct, such as cysts in the quadrigeminal cistern, ETV should be considered if it can be performed safely, in preparation for the worsening of hydrocephalus due to obstruction by enlargement of the cyst.


Assuntos
Cistos , Hidrocefalia , Neuroendoscopia , Criança , Pré-Escolar , Cistos/cirurgia , Feminino , Humanos , Hidrocefalia/diagnóstico por imagem , Hidrocefalia/etiologia , Hidrocefalia/cirurgia , Ventrículos Laterais/patologia , Masculino , Estudos Retrospectivos , Resultado do Tratamento , Ventriculostomia
3.
Plant Cell Physiol ; 62(12): 1874-1889, 2021 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-34197607

RESUMO

All land plants encode large multigene families of xyloglucan endotransglucosylase/hydrolases (XTHs), plant-specific enzymes that cleave and reconnect plant cell-wall polysaccharides. Despite the ubiquity of these enzymes, considerable uncertainty remains regarding the evolutionary history of the XTH family. Phylogenomic and comparative analyses in this study traced the non-plant origins of the XTH family to Alphaproteobacteria ExoKs, bacterial enzymes involved in loosening biofilms, rather than Firmicutes licheninases, plant biomass digesting enzymes, as previously supposed. The relevant horizontal gene transfer (HGT) event was mapped to the divergence of non-swimming charophycean algae in the Cryogenian geological period. This HGT event was the likely origin of charophycean EG16-2s, which are putative intermediates between ExoKs and XTHs. Another HGT event in the Cryogenian may have led from EG16-2s or ExoKs to fungal Congo Red Hypersensitive proteins (CRHs) to fungal CRHs, enzymes that cleave and reconnect chitin and glucans in fungal cell walls. This successive transfer of enzyme-encoding genes may have supported the adaptation of plants and fungi to the ancient icy environment by facilitating their sessile lifestyles. Furthermore, several protein evolutionary steps, including coevolution of substrate-interacting residues and putative intra-family gene fusion, occurred in the land plant lineage and drove diversification of the XTH family. At least some of those events correlated with the evolutionary gain of broader substrate specificities, which may have underpinned the expansion of the XTH family by enhancing duplicated gene survival. Together, this study highlights the Precambrian evolution of life and the mode of multigene family expansion in the evolutionary history of the XTH family.


Assuntos
Parede Celular/enzimologia , Embriófitas/enzimologia , Evolução Molecular , Família Multigênica , Proteínas de Plantas/genética , Glicosiltransferases/genética , Glicosiltransferases/metabolismo , Proteínas de Plantas/metabolismo
4.
Plant Cell ; 29(10): 2644-2660, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28899981

RESUMO

Ribosome-related mutants in Arabidopsis thaliana share several notable characteristics regarding growth and development, which implies the existence of a common pathway that responds to disorders in ribosome biogenesis. As a first step to explore this pathway genetically, we screened a mutagenized population of root initiation defective2 (rid2), a temperature-sensitive mutant that is impaired in pre-rRNA processing, and isolated suppressor of root initiation defective two1 (sriw1), a suppressor mutant in which the defects of cell proliferation observed in rid2 at the restrictive temperature was markedly rescued. sriw1 was identified as a missense mutation of the NAC transcription factor gene ANAC082 The sriw1 mutation greatly alleviated the developmental abnormalities of rid2 and four other tested ribosome-related mutants, including rid3 However, the impaired pre-rRNA processing in rid2 and rid3 was not relieved by sriw1 Expression of ANAC082 was localized to regions where phenotypic effects of ribosome-related mutations are readily evident and was elevated in rid2 and rid3 compared with the wild type. These findings suggest that ANAC082 acts downstream of perturbation of biogenesis of the ribosome and may mediate a set of stress responses leading to developmental alterations and cell proliferation defects.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Regulação da Expressão Gênica de Plantas , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Processamento Pós-Transcricional do RNA/fisiologia , Ribossomos/metabolismo
5.
PLoS Biol ; 11(1): e1001474, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23382651

RESUMO

Plants continuously extend their root and shoot systems through the action of meristems at their growing tips. By regulating which meristems are active, plants adjust their body plans to suit local environmental conditions. The transport network of the phytohormone auxin has been proposed to mediate this systemic growth coordination, due to its self-organising, environmentally sensitive properties. In particular, a positive feedback mechanism termed auxin transport canalization, which establishes auxin flow from active shoot meristems (auxin sources) to the roots (auxin sinks), has been proposed to mediate competition between shoot meristems and to balance shoot and root growth. Here we provide strong support for this hypothesis by demonstrating that a second hormone, strigolactone, regulates growth redistribution in the shoot by rapidly modulating auxin transport. A computational model in which strigolactone action is represented as an increase in the rate of removal of the auxin export protein, PIN1, from the plasma membrane can reproduce both the auxin transport and shoot branching phenotypes observed in various mutant combinations and strigolactone treatments, including the counterintuitive ability of strigolactones either to promote or inhibit shoot branching, depending on the auxin transport status of the plant. Consistent with this predicted mode of action, strigolactone signalling was found to trigger PIN1 depletion from the plasma membrane of xylem parenchyma cells in the stem. This effect could be detected within 10 minutes of strigolactone treatment and was independent of protein synthesis but dependent on clathrin-mediated membrane trafficking. Together these results support the hypothesis that growth across the plant shoot system is balanced by competition between shoot apices for a common auxin transport path to the root and that strigolactones regulate shoot branching by modulating this competition.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/crescimento & desenvolvimento , Compostos Heterocíclicos com 3 Anéis/metabolismo , Lactonas/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Brotos de Planta/crescimento & desenvolvimento , Arabidopsis/metabolismo , Transporte Biológico , Membrana Celular , Clatrina/metabolismo , Simulação por Computador , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Ácidos Indolacéticos/metabolismo , Lactonas/farmacologia , Proteínas de Membrana Transportadoras/deficiência , Meristema/crescimento & desenvolvimento , Meristema/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Raízes de Plantas/metabolismo , Brotos de Planta/metabolismo , Caules de Planta/crescimento & desenvolvimento , Caules de Planta/metabolismo , Transdução de Sinais/efeitos dos fármacos , Xilema/metabolismo
6.
J Plant Res ; 128(6): 975-86, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26464036

RESUMO

Xylogenesis, a process by which woody tissues are formed, entails qualitative and quantitative changes in the cell wall. However, the molecular events that underlie these changes are not completely understood. Previously, we have isolated two monoclonal antibodies, referred to as XD3 and XD27, by subtractive screening of a phage-display library of antibodies raised against a wall fraction of Zinnia elegans xylogenic culture cells. Here we report the biochemical and immunohistochemical characterization of those antibodies. The antibody XD3 recognized (1→4)-ß-D-galactan in pectin fraction. During xylogenesis, the XD3 epitope was localized to the primary wall of tracheary-element precursor cells, which undergo substantial cell elongation, and was absent from mature tracheary elements. XD27 recognized an arabinogalactan protein that was bound strongly to a germin-like protein. The XD27 epitope was localized to pre-lignified secondary walls of tracheary elements. Thus these cell-wall-directed monoclonal antibodies revealed two molecular events during xylogenesis. The biological significance of these events is discussed in relation to current views of the plant cell wall.


Assuntos
Asteraceae/genética , Parede Celular/metabolismo , Glicoproteínas/genética , Proteínas de Plantas/genética , Xilema/crescimento & desenvolvimento , Sequência de Aminoácidos , Anticorpos Monoclonais/metabolismo , Asteraceae/classificação , Asteraceae/crescimento & desenvolvimento , Asteraceae/metabolismo , Glicoproteínas/química , Glicoproteínas/metabolismo , Dados de Sequência Molecular , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Alinhamento de Sequência
7.
Biochim Biophys Acta ; 1831(12): 1690-701, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23994608

RESUMO

Anandamide and other bioactive N-acylethanolamines (NAEs) are a class of lipid mediators and are produced from glycerophospholipids via N-acylphosphatidylethanolamines (NAPEs). Although the generation of NAPE by N-acylation of phosphatidylethanolamine is thought to be the rate-limiting step of NAE biosynthesis, the enzyme responsible, N-acyltransferase, remains poorly characterized. Recently, we found that five members of the HRAS-like suppressor (HRASLS) family, which were originally discovered as tumor suppressors, possess phospholipid-metabolizing activities including NAPE-forming N-acyltransferase activity, and proposed to call HRASLS1-5 phospholipase A/acyltransferase (PLA/AT)-1-5, respectively. Among the five members, PLA/AT-1 attracts attention because of its relatively high N-acyltransferase activity and predominant expression in testis, skeletal muscle, brain and heart of human, mouse and rat. Here, we examined the formation of NAPE by PLA/AT-1 in living cells. As analyzed by metabolic labeling with [(14)C]ethanolamine or [(14)C]palmitic acid, the transient expression of human, mouse and rat PLA/AT-1s in COS-7 cells as well as the stable expression of human PLA/AT-1 in HEK293 cells significantly increased the generation of NAPE and NAE. Liquid chromatography-tandem mass spectrometry also exhibited that the stable expression of PLA/AT-1 enhanced endogenous levels of NAPE, N-acylplasmenylethanolamine, NAE and glycerophospho-NAE. Furthermore, the knockdown of endogenous PLA/AT-1 in mouse ATDC5 cells lowered NAPE levels. Interestingly, the dysfunction of peroxisomes, which was caused by PLA/AT-2 and -3, was not observed in the PLA/AT-1-expressing HEK293 cells. Altogether, these results suggest that PLA/AT-1 is at least partly responsible for the generation of NAPE in mammalian cells.


Assuntos
Etanolaminas/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Fosfatidiletanolaminas/biossíntese , Fosfolipases A/metabolismo , Acilação , Animais , Células COS , Radioisótopos de Carbono , Chlorocebus aethiops , Etanolamina/metabolismo , Regulação da Expressão Gênica , Células HEK293 , Humanos , Isoenzimas/antagonistas & inibidores , Isoenzimas/genética , Isoenzimas/metabolismo , Proteínas de Membrana Transportadoras/genética , Camundongos , Ácido Palmítico/metabolismo , Peroxissomos/metabolismo , Fosfolipases A/antagonistas & inibidores , Fosfolipases A/genética , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Ratos , Transdução de Sinais
8.
Environ Sci Technol ; 48(12): 6882-90, 2014 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-24856876

RESUMO

Asbestos-containing debris generated by the tsunami after the Great East Japan Earthquake of March 11, 2011, was processed by microwave heating. The analysis of the treated samples employing thermo gravimetry, differential thermal analysis, X-ray diffractometry, scanning electron microscopy, and phase-contrast microscopy revealed the rapid detoxification of the waste by conversion of the asbestos fibers to a nonfibrous glassy material. The detoxification by the microwave method occurred at a significantly lower processing temperature than the thermal methods actually established for the treatment of asbestos-containing waste. The lower treatment temperature is considered to be a consequence of the microwave penetration depth into the waste material and the increased intensity of the microwave electric field in the gaps between the asbestos fibers resulting in a rapid heating of the fibers inside the debris. A continuous treatment plant having a capacity of 2000 kg day(-1) of asbestos-containing waste was built in the area affected by the earthquake disaster. This treatment plant consists of a rotary kiln to burn the combustible waste (wood) and a microwave rotary kiln to treat asbestos-containing inorganic materials. The hot flue gas produced by the combustion of wood is introduced into the connected microwave rotary kiln to increase the energy efficiency of the combined process. Successful operation of this combined device with regard to asbestos decomposition is demonstrated.


Assuntos
Amianto/química , Desastres , Recuperação e Remediação Ambiental/métodos , Micro-Ondas , Resíduos/análise , Análise Diferencial Térmica , Terremotos , Japão , Microscopia Eletrônica de Varredura , Microscopia de Contraste de Fase , Temperatura , Termogravimetria , Difração de Raios X
9.
Bioelectromagnetics ; 35(2): 108-15, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24123106

RESUMO

We investigated whether extremely low frequency (ELF) magnetic field exposure has modification effects on cell survival after ultraviolet B (UV-B) irradiation and on repair process of DNA damage induced by UV-B irradiation in WI38VA13 subcloned 2RA and XP2OS(SV) cells. The ELF magnetic field exposure was conducted using a Helmholtz coil-based system that was designed to generate a sinusoidal magnetic field at 5 mT and 60 Hz. Cell survival was assessed by WST assay after UV-B irradiation at 20-80 J/m(2) , ELF magnetic field exposure for 24 h, followed by incubation for 48 h. DNA damage was assessed by quantification of cyclobutane pyrimidine dimer formation and 6-4 photoproduct formation using ELISA after UV-B irradiation at 20-80 J/m(2) followed by ELF magnetic field exposure for 24 h. No significant changes were observed in cell survival between ELF magnetic field and sham exposures. Similarly, DNA damage induced by UV-B irradiation did not change significantly following ELF magnetic field exposure. Our results suggest that ELF magnetic field exposure at 5 mT does not have modification effect on cell survival after UV-B irradiation and on repair process of DNA damage induced by UV-B irradiation.


Assuntos
Dano ao DNA , Campos Magnéticos , Raios Ultravioleta/efeitos adversos , Linhagem Celular , Sobrevivência Celular/efeitos da radiação , Células Clonais/citologia , Células Clonais/metabolismo , Reparo do DNA/efeitos da radiação , Humanos , Dímeros de Pirimidina/metabolismo
10.
J Biol Chem ; 287(38): 31905-19, 2012 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-22825852

RESUMO

Bioactive N-acylethanolamines (NAEs), including N-palmitoylethanolamine, N-oleoylethanolamine, and N-arachidonoylethanolamine (anandamide), are formed from membrane glycerophospholipids in animal tissues. The pathway is initiated by N-acylation of phosphatidylethanolamine to form N-acylphosphatidylethanolamine (NAPE). Despite the physiological importance of this reaction, the enzyme responsible, N-acyltransferase, remains molecularly uncharacterized. We recently demonstrated that all five members of the HRAS-like suppressor tumor family are phospholipid-metabolizing enzymes with N-acyltransferase activity and are renamed HRASLS1-5 as phospholipase A/acyltransferase (PLA/AT)-1-5. However, it was poorly understood whether these proteins were involved in the formation of NAPE in living cells. In the present studies, we first show that COS-7 cells transiently expressing recombinant PLA/AT-1, -2, -4, or -5, and HEK293 cells stably expressing PLA/AT-2 generated significant amounts of [(14)C]NAPE and [(14)C]NAE when cells were metabolically labeled with [(14)C]ethanolamine. Second, as analyzed by liquid chromatography-tandem mass spectrometry, the stable expression of PLA/AT-2 in cells remarkably increased endogenous levels of NAPEs and NAEs with various N-acyl species. Third, when NAPE-hydrolyzing phospholipase D was additionally expressed in PLA/AT-2-expressing cells, accumulating NAPE was efficiently converted to NAE. We also found that PLA/AT-2 was partly responsible for NAPE formation in HeLa cells that endogenously express PLA/AT-2. These results suggest that PLA/AT family proteins may produce NAPEs serving as precursors of bioactive NAEs in vivo.


Assuntos
Aciltransferases/química , Regulação da Expressão Gênica , Fosfatidiletanolaminas/química , Fosfolipases A/química , Animais , Sequência de Bases , Células COS , Chlorocebus aethiops , Células HEK293 , Células HeLa , Humanos , Dados de Sequência Molecular , Família Multigênica , Peroxissomos/metabolismo , Fosfolipase D/metabolismo , Fosfolipídeos/química , Interferência de RNA , Espectrometria de Massas em Tandem/métodos
11.
Development ; 137(17): 2905-13, 2010 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-20667910

RESUMO

Strigolactones (SLs), or their derivatives, were recently demonstrated to act as endogenous shoot branching inhibitors, but their biosynthesis and mechanism of action are poorly understood. Here we show that the branching phenotype of mutants in the Arabidopsis P450 family member, MAX1, can be fully rescued by strigolactone addition, suggesting that MAX1 acts in SL synthesis. We demonstrate that SLs modulate polar auxin transport to control branching and that both the synthetic SL GR24 and endogenous SL synthesis significantly reduce the basipetal transport of a second branch-regulating hormone, auxin. Importantly, GR24 inhibits branching only in the presence of auxin in the main stem, and enhances competition between two branches on a common stem. Together, these results support two current hypotheses: that auxin moving down the main stem inhibits branch activity by preventing the establishment of auxin transport out of axillary branches; and that SLs act by dampening auxin transport, thus enhancing competition between branches.


Assuntos
Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Ácidos Indolacéticos/metabolismo , Lactonas/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Sequência de Bases , Transporte Biológico Ativo/efeitos dos fármacos , Primers do DNA/genética , Genes de Plantas , Lactonas/farmacologia , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Mutação , Fenótipo , Brotos de Planta/efeitos dos fármacos , Plantas Geneticamente Modificadas , Xilema/efeitos dos fármacos , Xilema/metabolismo
12.
Surg Today ; 43(2): 185-90, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22653468

RESUMO

PURPOSE: Collagen and fibrin are known to have potential use as a local drug-delivery system. This experimental study was designed to evaluate whether a fibrinogen-based collagen (FBC) fleece, coated with thrombin and aprotinin, can be used as an antibiotic delivery system. METHODS: In an in vitro study, gentamicin, fosfomycin, ampicillin, ciprofloxacin and dibekacin were absorbed by the FBC, Kirby-Bauer disks (KBDs), and expanded polytetrafluoroethylene. After washing with saline or phosphate buffer saline (PBS) 3 times for 6, 12 and 24 h, each sample was analyzed for antibiotic retention. In an in vivo study, we implanted the FBC onto mouse livers and dripped gentamicin and ciprofloxacin onto the FBC. The FBCs were subsequently collected and analyzed for their antibiotic activities. RESULTS: After irrigation with saline, each antibiotic showed different activities. After PBS washing, the FBC impregnated with each antibiotic had higher activity than the KBDs, and inhibited the bacterial growth by 60-80 % compared to the control. Gentamicin dripped onto the FBC could inhibit bacterial growth after 48 h in vivo without affecting the hemostatic properties of the FBC. However, the FBC treated with ciprofloxacin exhibited antibacterial activity for only 3 h. CONCLUSIONS: Some bases, including FBC, can retain antibacterial activities dependent on the ingredients of the base and the type of antibiotic. Gentamicin, but not ciprofloxacin, was retained in the FBC in vivo. These results suggest that absorbent FBC might be useful not only as hemostatic material, but also as a local drug-delivery system.


Assuntos
Antibacterianos/administração & dosagem , Aprotinina , Sistemas de Liberação de Medicamentos , Fibrinogênio , Trombina , Ampicilina/administração & dosagem , Ampicilina/farmacologia , Animais , Antibacterianos/farmacologia , Ciprofloxacina/administração & dosagem , Ciprofloxacina/farmacologia , Dibecacina/administração & dosagem , Dibecacina/farmacologia , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Combinação de Medicamentos , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Fosfomicina/administração & dosagem , Fosfomicina/farmacologia , Gentamicinas/administração & dosagem , Gentamicinas/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Politetrafluoretileno
13.
Phys Rev E ; 108(4-2): 045207, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37978721

RESUMO

With the advancement in the understanding of plasma discontinuous structures and the progress of related research, numerical methods for simulating plasmas based on continuous medium approach have encountered significant challenges. In this paper, a numerical model is presented to simulate the motion trajectory of an atmospheric pressure plasma jet under an external nonuniform electric field. The method proposes to treat the plasma jet as equivalent particles with permittivity and conductivity, based on its dielectric properties and motion characteristics. The numerical model demonstrates short calculation times and excellent agreement between simulation results and experimental observations, validating its high efficiency and effectiveness. This work contributes to a deeper understanding of the collective effect of the plasma jet and provides an effective and efficient method for predicting the motion trajectory of the plasma jet, along with guidelines for controlling plasma using external nonuniform electric fields.

14.
Surg Neurol Int ; 14: 165, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37292402

RESUMO

Background: The ventriculus terminalis (VT) is a cystic embryological remnant of the conus medullaris that usually regresses after birth. This structure rarely persists into adulthood and may produce neurological symptoms. We recently encountered three cases of symptomatic enlarging VT. Case Description: The three female patients were 78, 64, and 67 years old. Symptoms included pain, numbness, motor weakness, and frequent urination that gradually worsened. Magnetic resonance imaging revealed cystic dilatations of slow growing VT. These patients showed marked improvement after cyst-subarachnoid shunt using a syringo-subarachnoid shunt tube. Conclusion: Symptomatic enlarging VT is an extremely rare cause of conus medullaris syndrome and the optimal treatment strategy remains unclear. Surgical management may thus be appropriate for patients with symptomatic enlarging VT.

15.
J Neuroendovasc Ther ; 17(9): 202-208, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37731467

RESUMO

Objective: This is a report on the usefulness of 3D fusion imaging with susceptibility-weighted imaging (SWI) as preoperative imaging for mechanical thrombectomy (MT) for acute ischemic stroke (AIS). Case Presentations: Among 17 cases of patients who underwent MT in AIS between March 2021 and April 2022, 14 patients who underwent MRI with SWI (shortened SWI for stroke) and 3D T2-weighted sampling perfection with application-optimized contrasts using different flip angle evolution were targeted in the study. Three cases with motion artifacts due to body movement were excluded from the images.After imaging, 3D fusion images were constructed to visualize thrombi and occluded vessels. SWI for stroke obtained thrombus information in 11 of the 14 cases (78.5%) and 3D images of the thrombi could be created in all 11 cases. 3D fusion images could be created in nine of the 14 cases (64.2%). Conclusion: 3D fusion images, using SWI for stroke, can visualize thrombi and occluded vessels and may be effectively used as preoperative images for MT.

16.
Bioelectromagnetics ; 33(8): 662-9, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22566076

RESUMO

The increased use of induction heating (IH) cooktops in Japan and Europe has raised public concern on potential health effects of the magnetic fields generated by IH cooktops. In this study, we evaluated the effects of intermediate frequency (IF) magnetic fields generated by IH cooktops on gene expression profiles. Human fetus-derived astroglia cells were exposed to magnetic fields at 23 kHz and 100 µT(rms) for 2, 4, and 6 h and gene expression profiles in cells were assessed using cDNA microarray. There were no detectable effects of the IF magnetic fields at 23 kHz on the gene expression profile, whereas the heat treatment at 43 °C for 2 h, as a positive control, affected gene expression including inducing heat shock proteins. Principal component analysis and hierarchical analysis showed that the gene profiles of IF-exposed groups were similar to the sham-exposed group and were different than the heat treatment group. These results demonstrated that exposure of human fetus-derived astroglia cells to an IF magnetic field at 23 kHz and 100 µT(rms) for up to 6 h did not induce detectable changes in gene expression profile.


Assuntos
Astrócitos/metabolismo , Astrócitos/efeitos da radiação , Campos Eletromagnéticos/efeitos adversos , Feto/citologia , Transcriptoma/efeitos da radiação , Astrócitos/citologia , Ciclo Celular/efeitos da radiação , Linhagem Celular , Humanos , Análise de Componente Principal , Temperatura , Fatores de Tempo
17.
J Neuroendovasc Ther ; 16(9): 452-457, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-37502793

RESUMO

Objective: Determining the course of occluded vessels in advance will increase the success rate and safety of mechanical thrombectomy (MT). Herein, we evaluate the usefulness of MR fusion images created via 3D T2-weighted sampling perfection with application-optimized contrasts using different flip angle evolutions (T2-SPACE) and 3D time-of-flight (TOF)-MRA for visualization of occluded vessels in patients with acute ischemic stroke (AIS) before MT. Methods: We enrolled 26 patients with AIS caused by intracranial large vessel occlusion who presented at our hospital and underwent MRI with fusion images unaffected by motion artifacts in our study. All patients underwent T2-SPACE and TOF-MRA followed by MT. We created fusion images of the T2-SPACE and TOF-MRA by combining a translucent image of the occluded artery produced by the flow void effect in T2-SPACE with the same vessel in a TOF-MRA image. Fusion images were compared with post-recanalization angiography and post-recanalization MRA, respectively, and the degree of agreement in depiction of M1 runs and M2 branching beyond the occlusion on three levels was assessed. Imaging evaluations were performed independently by two endovascular specialists. Results: The interobserver agreement of the MRI findings about the concordance of the occluded vessel's run was excellent (kappa was 0.87 [confidence interval: 0.61-1.12]). In all, 21 patients (80.8%) had excellent imaging, four (15.4%) had fair imaging, and one (3.8%) had a divided opinion of the rating between excellent and fair imaging. No cases were judged to be poorly drawn. Even if there was a localized signal loss, its distal portion could be delineated, so it did not affect the estimation of the entire vessel run, and we found that the anatomical structures of the occluded vessels were distinctly visible in the fusion images. Conclusion: We demonstrated that MR fusion images derived using T2-SPACE and MRA methodologies could determine the courses of occluded vessels prior to MT performed for AIS. Fusion MR imaging may have potential as a preoperative test for ensuring effective and safe MT procedures.

18.
Cureus ; 14(2): e22484, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35371681

RESUMO

OBJECTIVE: To extend life expectancy after surgery, patients with hip fractures need to improve their mobility quickly through postoperative rehabilitation. Voluntary hip joint motion supported by the hybrid assistive limb (HAL) lumbar type, an exoskeleton robot suit characterized by its ability to detect the wearer's intentions through the bioelectrical signals and assist hip extension motions at an optimal timing, may be effective to improve mobility in patients with hip joint dysfunction after surgery. We aimed to introduce rehabilitation using the HAL lumbar type in the early period after hip fracture surgery. METHODS: Patients who underwent internal fixation for hip fracture at a single institution were prospectively enrolled. They received early postoperative rehabilitation (forward and backward bending of the lumbar spine, pelvic tilt forward and backward, standing up, and squatting) using the HAL lumbar type (six times a week for 15 min per session). Five-times-sit-to-stand (FTSS) and timed-up-and-go (TUG) tests were conducted at baseline before HAL rehabilitation (pre-HAL) and after the HAL rehabilitation (post-HAL) intervention. RESULTS: We enrolled 14 patients (one man, 13 women) in this study. There were no adverse events, and all patients were able to complete the entire rehabilitation program. Post-HAL FTSS showed significant improvement compared with pre-HAL and had a large effect size of 1.81 (95% CI = 0.93 to 2.66) and sufficient power. CONCLUSIONS: Robotic rehabilitation with HAL lumbar type could be introduced without adverse events, even in the early postoperative period following surgery for hip fracture. Further study is needed to develop an appropriate rehabilitation protocol using the HAL lumbar type.

19.
J Lipid Res ; 52(11): 1927-35, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21880860

RESUMO

A-C1 protein is the product of a tumor suppressor gene negatively regulating the oncogene Ras and belongs to the HRASLS (HRAS-like suppressor) subfamily. We recently found that four members of this subfamily expressed in human tissues function as phospholipid-metabolizing enzymes. Here we examined a possible enzyme activity of A-C1. The homogenates of COS-7 cells overexpressing recombinant A-C1s from human, mouse, and rat showed a phospholipase A½ (PLA½) activity toward phosphatidylcholine (PC). This finding was confirmed with the purified A-C1. The activity was Ca²âº independent, and dithiothreitol and Nonidet P-40 were indispensable for full activity. Phosphatidylethanolamine (PE) was also a substrate and the phospholipase A1 (PLA1) activity was dominant over the PLA2 activity. Furthermore, the protein exhibited acyltransferase activities transferring an acyl group of PCs to the amino group of PEs and the hydroxyl group of lyso PCs. As for tissue distribution in human, mouse, and rat, A-C1 mRNA was abundantly expressed in testis, skeletal muscle, brain, and heart. These results demonstrate that A-C1 is a novel phospholipid-metabolizing enzyme. Moreover, the fact that all five members of the HRASLS subfamily, including A-C1, show similar catalytic properties strongly suggests that these proteins constitute a new class of enzymes showing PLA½ and acyltransferase activities.


Assuntos
Ensaios Enzimáticos , Fosfolipídeos/metabolismo , Proteínas/metabolismo , Sequência de Aminoácidos , Animais , Biocatálise , Células COS , Regulação Enzimológica da Expressão Gênica , Humanos , Camundongos , Dados de Sequência Molecular , Fosfolipases A , Proteínas/química , Proteínas/genética , Ratos
20.
Acta Radiol Open ; 10(3): 20584601211003233, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33815831

RESUMO

High-resolution vessel wall imaging techniques have been developed for clinical use in various types of intracranial artery disease. Numerous studies have described techniques for evaluating remodeling patterns and plaque character, but few have reported a method for outlining obstructed vessels in intracranial artery occlusion. The course of the vessel affects the success of recanalization and can cause complications in mechanical thrombectomy for acute ischemic stroke. We propose imaging with 3D T2-weighted sampling perfection with application optimized contrasts using different flip angle evolution (SPACE) as a useful tool for describing the course of an occluded artery in ischemic stroke due to intracranial artery occlusion.

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