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2.
J Pharmacol Sci ; 142(3): 116-123, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31924407

RESUMO

Neutrophils constitute the major population of infiltrating leukocytes after stroke including intracerebral hemorrhage (ICH), and these cells may exhibit pro-inflammatory and anti-inflammatory phenotypes depending on the external stimuli. Here we constructed an experimental system to evaluate how the properties of neutrophils were influenced by the injured brain tissues. HL60 cells differentiated into neutrophils were added to the culture medium of neonatal rat cortico-striatal slices maintained at liquid-air interface. Thrombin was applied to the cultures to mimic the pathogenic events associated with ICH. HL60 cells responded to thrombin by increasing mRNA expression of pro-inflammatory IL-1ß and anti-inflammatory IL-10 with a different time course. Co-presence of cortico-striatal slice cultures significantly enhanced IL-1ß mRNA expression, whereas attenuated IL-10 mRNA expression, in HL60 cells. Toll-like receptor 4 (TLR4) agonist lipopolysaccharide synergistically enhanced IL-1ß mRNA expression with thrombin, and TLR4 inhibitor TAK-242 abolished thrombin-induced IL-1ß mRNA expression in the presence of slice cultures. On the other hand, thrombin-induced cell death in cortico-striatal cultures was attenuated by the presence of HL60 cells. This experimental system may provide a unique platform to elucidate complex cell-to-tissue interactions during ICH pathogenesis.


Assuntos
Comunicação Celular , Neutrófilos , Trombina/farmacologia , Alarminas , Animais , Células Cultivadas , Citocinas , Células HL-60 , Humanos , Inflamação , Ratos Wistar , Trombina/fisiologia
3.
J Am Chem Soc ; 138(8): 2480-3, 2016 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-26760915

RESUMO

A mixture of an iron or a cobalt carboxylate and an isocyanide ligand catalyzed the hydrosilylation of alkenes with hydrosiloxanes with high efficiency (TON >10(3)) and high selectivity. The Fe catalyst showed excellent activity for hydrosilylation of styrene derivatives, whereas the Co catalyst was widely effective in reaction of alkenes. Both of them catalyzed the reaction with allylic ethers. Chemical modification and cross-linking of silicones were achieved by choosing the right catalyst and reaction conditions.

4.
Chem Commun (Camb) ; 50(74): 10793-6, 2014 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-25054472

RESUMO

Poly(N-cyanoethylethyleneimine) (PCEI) obtained by Michael addition of linear poly(ethyleneimine) (LPEI) with acrylonitrile provided novel nanocrystalline entities which could serve as catalytic templates affording nanosheet-based structured silica under mild conditions.


Assuntos
Materiais Biomiméticos/química , Polímeros/química , Dióxido de Silício/química , Acrilonitrila/química , Catálise , Géis/química , Nanoestruturas/química , Polietilenoimina/química , Polímeros/síntese química
5.
Beilstein J Nanotechnol ; 4: 793-804, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24367748

RESUMO

This paper describes a facile approach to a biomimetic rapid fabrication of ultrathin silica nanotubes with a highly uniform diameter of 10 nm and inner hollow of around 3 nm. The synthesis is carried out through a spontaneous polycondensation of alkoxysilane on polyamine crystalline fibrils that were conveniently produced from the neutralization of a solution of protonated linear polyethyleneimine (LPEI-H(+)) by alkali compounds. A simple mixing the fibrils with alkoxysilane in aqueous solution allowed for the rapid formation of silica to produce LPEI@silica hybrid nanotubes. These 10-nm nanotubes were hierarchically organized in a mat-like morphology with a typical size of 1-2 micrometers. The subsequent removal of organic LPEI via calcination resulted in silica nanotubes that keep this morphology. The morphology, the structure, the pore properties and the formation mechanism of the silica nanotubes were carefully investigated with scanning electron microscopy (SEM), transmission electron microscopy (TEM), Brunauer-Emmett-Teller measurements (BET), and X-ray diffraction (XRD). Detailed studies demonstrated that the formation of the nanotubes depends on the molar ratio of [OH]/[CH2CH2NH] during the neutralization as well as on the basicity of the alkali compound and on the concentration of the silica source. The synthesis of silica nanotubes established here could be easily applied to a fabrication on the kilogram scale. Silica nanotubes that were obtained from the calcination of hybrid nanotubes of LPEI@silica in an N2 atmosphere showed a distinct photoluminescence centered at 540 nm with a maximum excitation wavelength of 320 nm. Furthermore, LPEI@silica hybrid nanotubes were applied to create silica-carbon composite nanotubes by alternative adsorption of ionic polymers and subsequent carbonization.

6.
Chem Commun (Camb) ; 48(100): 12231-3, 2012 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-23147813

RESUMO

Treatment of (η(1)-mesityl)(2)Fe(κ(2)-TMEDA) (1') with an α,ß-unsaturated carbonyl compound results in 1,4-addition of the mesityl group to give an iron enolate quantitatively. The Z-configuration of the enolate suggested the six-centered mechanism for the conjugate addition.

7.
J Foot Ankle Surg ; 51(2): 234-6, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22153296

RESUMO

It is well known that rupture of the flexor hallucis longus tendon can be associated with open injuries and that closed rupture of the flexor hallucis longus tendon is rare. Tendon injuries of the foot can occur secondary to direct, indirect, or repetitive injury. Repetitive tendon injuries can cause tendinitis or stenosing tenosynovitis. Tendinitis is associated with internal tendon injury that can present with tendon thickening, mucinoid degeneration, nodule development, or in situ partial tears. Stenosing tenosynovitis is the development of tendon adhesions within the tendon sheath that interfere with tendon gliding, known as trigger toe. The flexor hallucis longus tendon is susceptible to injury along its entire course. A total of 35 cases of complete or partial closed ruptures of the flexor hallucis longus tendon have been reported. We present the case of complete subcutaneous rupture of the flexor hallucis longus tendon associated with trauma at the proximal phalangeal head.


Assuntos
Traumatismos dos Tendões/diagnóstico , Traumatismos dos Tendões/cirurgia , Dedos do Pé/lesões , Dedos do Pé/cirurgia , Acidentes por Quedas , Adulto , Traumatismos do Tornozelo/cirurgia , Feminino , Humanos , Imageamento por Ressonância Magnética , Ruptura/diagnóstico , Ruptura/cirurgia
8.
Nihon Jibiinkoka Gakkai Kaiho ; 112(10): 712-7, 2009 Oct.
Artigo em Japonês | MEDLINE | ID: mdl-19894593

RESUMO

We report a rare case of adenosquamous carcinoma of the larynx. A 38-year-old man with a 9-month history of progressive hoarseness and dyspnea during exercise and sudden-onset breathing difficulty was unable to be intubated and underwent a tracheostomy at the emergency department. He was found in endoscopic examination of the larynx to have a large smooth subglottic mass with laryngeal stenosis. The bilateral vocal cords were fixed. No cervical lymph node was seen. Excisional laryngofissure biopsy led to a pathological diagnosis of adenosquamous carcinoma, necessitating laryngectomy with bilateral neck dissection (Level II-IV) and postoperative radiation therapy. He died of metastatic disease 7.5 years after the initial treatment, without locoregional recurrence. Among malignant laryngeal tumors, adenosquamous carcinoma is extremely rare, with only 33 such cases including ours reported in the literature.


Assuntos
Carcinoma Adenoescamoso , Neoplasias Laríngeas , Adulto , Carcinoma Adenoescamoso/patologia , Humanos , Neoplasias Laríngeas/patologia , Masculino
9.
J Am Chem Soc ; 131(17): 6078-9, 2009 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-19364096

RESUMO

A new reaction mechanism for the iron-catalyzed cross-coupling reaction of ArMgX with alkyl halides using (TMEDA)FeAr(2) and (TMEDA)Fe(Ar)Br is proposed on the basis of the isolation and reaction of these organoiron intermediates.

10.
No Shinkei Geka ; 36(8): 717-23, 2008 Aug.
Artigo em Japonês | MEDLINE | ID: mdl-18700535

RESUMO

We report a case of idiopathic hypertrophic pachymeningitis presenting with cranial hyperostosis. A 64-year-old man had suffered from pulsating headache during the last 3 months. CT showed bony thickening of the sphenoid ridge, and MRI with Gd-DTPA revealed a linear or nodular enhanced mass along the left sphenoid ridge, extending to the anterior and middle cranial fossae and cavernous sinus. Preoperative steroid therapy resulted in improved clinical symptoms and shrinkage of the enhanced lesion. To clarify the nature of the lesion, biopsy was performed. Granulation tissue infiltrated by lymphocytes and plasma cells was identified, suggesting inflammatory changes. Histologic examination of the cranial bone showed fibrosis in the bone marrow. We considered the hyperostosis to have resulted from a long-term nonspecific inflammatory reaction. Idiopathic hypertrophic pachymeningitis associated with skull changes is rare. There are only 4 reported cases including ours. This rare condition is important in the differential diagnosis of cranial hyperostosis.


Assuntos
Hiperostose/diagnóstico , Hiperostose/etiologia , Meningite/complicações , Crânio , Diagnóstico Diferencial , Diagnóstico por Imagem , Humanos , Hiperostose/patologia , Hiperostose/terapia , Masculino , Meningite/diagnóstico , Meningite/patologia , Meningite/terapia , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos , Prednisolona/administração & dosagem
11.
J Periodontal Res ; 38(5): 525-32, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12941078

RESUMO

OBJECTIVE: The process of dental root resorption and subsequent cementum regeneration has not been sufficiently elucidated. This study aimed to examine the process of the root resorption and cementum regeneration during physiological tooth drift using a rat model, and to evaluate this experimental model. METHODS: Distal roots in mandibular first molars and the surrounding periodontal tissues were investigated with light and electron microscopy. The light microscopic approach included histochemical and histometric analyses utilizing the tartrate-resistant acid phosphatase (TRAP) reaction. RESULTS: Root resorption was observed in the distal side of the roots and was most active in 5- to 6-week-old rats, and gradually decreased hereafter. An increase in the number of TRAP-positive mononuclear cells, which seemed to be odontoclast precursor cells, preceded the increase in the number of odontoclasts. Root resorption was transient, and was followed by the new formation of acellular extrinsic fiber cementum accompanied with only a slight inflammation, and therefore classified as external surface resorption. Preparation for new cementum started adjacent to the resorption areas when root resorption was most active. CONCLUSIONS: The root resorption during drift in rats is transient and followed by acellular extrinsic fiber cementum regeneration. Cellular kinetics suggested that odontoclast precursor cells are supplied as mononuclear cells from vascular spaces.


Assuntos
Cemento Dentário/fisiologia , Reabsorção da Raiz/fisiopatologia , Migração de Dente , Fosfatase Ácida , Animais , Corantes , Isoenzimas , Microscopia Eletrônica de Varredura , Osteoclastos/fisiologia , Osteoclastos/ultraestrutura , Ratos , Ratos Wistar , Regeneração , Reabsorção da Raiz/etiologia , Fosfatase Ácida Resistente a Tartarato , Migração de Dente/complicações
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