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1.
Nat Mater ; 21(4): 410-415, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35145257

RESUMO

Rare-earth intermetallic compounds exhibit rich phenomena induced by the interplay between localized f orbitals and conduction electrons. However, since the energy scale of the crystal-electric-field splitting is only a few millielectronvolts, the nature of the mobile electrons accompanied by collective crystal-electric-field excitations has not been unveiled. Here, we examine the low-energy electronic structures of CeSb through the anomalous magnetostructural transitions below the Néel temperature, ~17 K, termed the 'devil's staircase', using laser angle-resolved photoemission, Raman and neutron scattering spectroscopies. We report another type of electron-boson coupling between mobile electrons and quadrupole crystal-electric-field excitations of the 4f orbitals, which renormalizes the Sb 5p band prominently, yielding a kink at a very low energy (~7 meV). This coupling strength is strong and exhibits anomalous step-like enhancement during the devil's staircase transition, unveiling a new type of quasiparticle, named the 'multipole polaron', comprising a mobile electron dressed with a cloud of the quadrupole crystal-electric-field polarization.

2.
Osteoporos Int ; 33(2): 505-509, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34494146

RESUMO

We report a 64-year-old Japanese woman with a history of progressive loss of motor function and painful swelling of large joints. At the age of 54, profound calcification appeared around the shoulder and hip joints, which did not heal after repeated surgical resections. Iliac bone biopsy revealed osteomalacic changes. Laboratory data showed low serum alkaline phosphatase (ALP) activity and a high urine phosphoethanolamine (PEA) concentration with normal serum calcium, phosphate, and fibroblast growth factor 23 (FGF23) levels. Subsequent genetic analysis of the ALPL gene confirmed the diagnosis of hypophosphatasia (HPP) with the identification of a heterozygous single nucleotide deletion, c.1559delT (p.Leu520ArgfsX86). We started a mineral-targeted enzyme replacement therapy, asfotase alfa (AA), to treat the patient's musculoskeletal symptoms. A follow-up bone biopsy after 12 months of AA treatment showed improvement of osteomalacia. Calcified deposits around the large joints were unchanged radiographically. To our knowledge, this is the first report of a patient with an adult-onset HPP who presented with profound calcification around multiple joints. Nonspecific clinical signs and symptoms in patients with adult-onset HPP often result in delayed diagnosis or misdiagnosis. We propose that bone biopsy and genetic analysis should be considered along with laboratory analysis for all patients with ectopic calcification around joints of unknown etiology for accurate diagnosis and better treatment.


Assuntos
Calcinose/etiologia , Hipofosfatasia , Adulto , Fosfatase Alcalina/uso terapêutico , Terapia de Reposição de Enzimas , Feminino , Fatores de Crescimento de Fibroblastos , Humanos , Hipofosfatasia/complicações , Hipofosfatasia/diagnóstico , Hipofosfatasia/tratamento farmacológico , Pessoa de Meia-Idade
3.
Artigo em Inglês | MEDLINE | ID: mdl-26603595

RESUMO

This longitudinal descriptive study examined whether rectal cancer patients report changes in health-related quality of life (HRQOL) over a 6-month period after different types of sphincter-saving surgery (SSS): intersphincteric resection (ISR), ultra-low anterior resection (ULAR) and low anterior resection (LAR). It also compares HRQOL among the three groups of patients. Seventy-three patients from two hospitals in Japan completed questionnaires on HRQOL and defecation symptoms immediately before surgery and 1 and 6 months afterwards. Results showed that ISR patients had significantly worse HRQOL scores than ULAR and LAR patients and more defecation symptoms that persisted during the 6 months post-SSS. Thus, patients undergoing ISR require psychological and social support, including skills in competent self-management, during the early post-operative period. Furthermore, defecation problems substantially influence HRQOL. The first month post-SSS is particularly challenging. The assumption that HRQOL is better after SSS compared to living with a permanent stoma might not be valid.


Assuntos
Qualidade de Vida , Neoplasias Retais/cirurgia , Atividades Cotidianas , Canal Anal/cirurgia , Análise de Variância , Defecação/fisiologia , Feminino , Seguimentos , Nível de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Tratamentos com Preservação do Órgão/métodos , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/fisiopatologia , Estudos Prospectivos , Neoplasias Retais/fisiopatologia , Autocuidado , Apoio Social
4.
Nano Lett ; 16(12): 7490-7494, 2016 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-27786489

RESUMO

We report on a low-temperature atomic force microscropy manipulation of Co atoms in ultrahigh vacuum on an oxidized copper surface in which the manipulated atom is kept delocalized above several surface unit cells over macroscopic times. The manipulation employed, in addition to the ubiquitous short-range tip-generated chemical forces, also long-range forces generated via Friedel oscillations of the metal charge density due to Co nanostructures prearranged on the surface by lateral manipulation. We show that our manipulation protocol requires mechanical control of the spin state of the Co atom.

6.
Vet Pathol ; 52(6): 1012-8, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25653203

RESUMO

The authors herein describe the morphologic and immunohistochemical features of normal Merkel cells as well as the clinicopathologic findings of Merkel cell carcinoma in cats. Merkel cells were characterized as vacuolated clear cells and were individually located in the epidermal basal layer of all regions examined. Clusters of Merkel cells were often observed adjacent to the sinus hair of the face and carpus. Immunohistochemically, Merkel cells were positive for cytokeratin (CK) 20, CK18, p63, neuron-specific enolase, synaptophysin, and protein gene product 9.5. Merkel cell carcinoma was detected as a solitary cutaneous mass in 3 aged cats (13 to 16 years old). On cytology, large lymphocyte-like cells were observed in all cases. Histologic examinations of surgically resected tumors revealed nests of round cells separated by various amounts of a fibrous stroma. Tumor cells were commonly immunopositive for CK20, CK18, p63, neuron-specific enolase, and synaptophysin, representing the characteristics of normal Merkel cells.


Assuntos
Biomarcadores Tumorais/análise , Carcinoma de Célula de Merkel/veterinária , Doenças do Gato/patologia , Neoplasias Cutâneas/veterinária , Animais , Carcinoma de Célula de Merkel/patologia , Gatos , Feminino , Queratinas/análise , Masculino , Células de Merkel/metabolismo , Neurônios/metabolismo , Fosfopiruvato Hidratase/análise , Neoplasias Cutâneas/patologia , Sinaptofisina/análise
7.
BJOG ; 121(7): 866-74; discussion 875, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24666658

RESUMO

OBJECTIVE: To clarify the effects of uterine myometrial suture techniques at prior caesarean section on the incidence of pathologically diagnosed placenta accreta in placenta praevia with prior caesarean section (PPPC). DESIGN: Case-control study. SETTING: Eleven tertiary referral hospitals in central Japan. POPULATION: A total of 98 cases of placenta praevia, a history of one or more prior caesarean sections, and a history of uterine transverse incision and usage of only absorbable thread for myometrial sutures at the prior caesarean section. Exclusions were a history of myomectomy or Strassmann's operation. METHODS: Cases were grouped into a pathologically diagnosed placenta accreta group (38 cases) and a no accreta group (60 cases). Clinical characteristics including uterine suture methods at prior caesarean section were compared (single-layer versus double-layer closure; continuous versus interrupted sutures in the inner myometrial layer). MAIN OUTCOME MEASURE: The incidence of placenta accreta. RESULTS: No difference was found comparing single-layer with double-layer closure in the incidence of placenta accreta (37.1 versus 39.7%, P = 0.805); however, a significant difference was found comparing continuous with interrupted sutures (58.1 versus 29.9%, P = 0.008). Multivariable logistic regression analysis with stepwise selection for the eight factors meeting the criterion of P < 0.10 in univariate analysis was used, and four independent factors were selected, as follows: gravidity ≥ 3 (adjusted odds ratio, aOR, 3.4, 95% confidence interval, 95% CI, 0.99-11.6, P = 0.050); total praevia (versus non-total, aOR 18.4, 95% CI 3.2-107.0, P = 0.001); anterior/centre placenta (versus posterior, aOR 16.4, 95% CI 3.7-72.2, P < 0.001); and continuous sutures (versus interrupted, aOR 6.0, 95% CI 1.4-25.2, P = 0.015). CONCLUSIONS: In this limited study, a history of continuous sutures on the inner side of the uterine wall showed potential to influence the development of placenta accreta in PPPC patients.


Assuntos
Cesárea/efeitos adversos , Cesárea/métodos , Placenta Acreta/epidemiologia , Placenta Acreta/etiologia , Técnicas de Sutura/efeitos adversos , Útero/cirurgia , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Incidência , Placenta Prévia , Gravidez , Estudos Retrospectivos
8.
Rev Sci Instrum ; 93(7): 073702, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35922319

RESUMO

We have developed a long-distance polarizing microscope system combined with a solenoid-type superconducting magnet. By inserting an infinity-corrected objective lens into the magnet, direct or polarizing microscope images are observed in magnetic fields of up to 12 T at various temperatures down to 2 K. Through magneto-optical measurements in the transmission geometry, the local magnetization process of a transparent magnet is evaluated in areas of 10 × 10 µm2. This system enables simultaneous measurements of other physical properties over a wide range of temperatures and magnetic fields. The basic principle of the proposed long-distance microscopy can be applied to imaging experiments in various research fields, particularly biology and chemistry.

9.
Int J Androl ; 34(3): 268-75, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20522123

RESUMO

The aim of this study was to investigate the effect of ischaemic post-conditioning (IPostC) against ischaemia-reperfusion (IR) injury on bilateral testes after unilateral testicular ischaemia in the rat. Eight-week-old male Sprague-Dawley rats were divided into control group; IR group (60 min ischaemia-24 h reperfusion); IPostC1 × 10 group (60 min ischaemia followed by one cycle of 10 sec reperfusion-10 sec ischaemia; then 24 h reperfusion); IPostC3 × 10 group (three cycles of 10 sec reperfusion-10 sec ischaemia; then 24 h reperfusion); IPostC5 × 10 group (five cycles of 10 sec reperfusion-10 sec ischaemia; then 24 h reperfusion) and IPostC3 × 30 group (three cycles of 30 sec reperfusion-30 sec ischaemia; then 24 h reperfusion). In the IR and IPostC groups, the right testicular vessels were clamped using a special vascular clip. Malondialdehyde (MDA) and myeloperoxidase (MPO) levels were measured in testicular tissue samples bilaterally. Additionally, bilateral testicular tissue samples were processed for histological evaluation including haematoxylin-eosin, 4-hydroxy-2-nonenal (4-HNE) and TdT-mediated dUTP Nick End Labelling (TUNEL) staining. The levels of MDA and MPO as well as the positive cells per seminiferous tubule in TUNEL and 4-HNE stain in bilateral testes from the IR group were significantly higher compared with the control group. IPostC3 × 30 protocol significantly ameliorated the aforesaid parameters in both testes compared with the IR group. For the first time, we have demonstrated that IPostC protects both testes after unilateral testicular ischaemia-reperfusion. IPostC3 × 30 protocol offered the most effective protection.


Assuntos
Pós-Condicionamento Isquêmico , Traumatismo por Reperfusão , Testículo/lesões , Animais , Infertilidade Masculina/prevenção & controle , Masculino , Malondialdeído/análise , Estresse Oxidativo , Peroxidase/análise , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio , Torção do Cordão Espermático/patologia , Torção do Cordão Espermático/terapia , Testículo/irrigação sanguínea , Testículo/patologia
10.
Clin Exp Immunol ; 159(2): 185-98, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19912257

RESUMO

Several negative regulatory mechanisms control Toll-like receptor (TLR)-mediated inflammatory responses and restore immune system balance, including the zinc-finger protein A20, a negative regulator of TLR signalling that inhibits nuclear factor kappa B (NF-kappaB) activity. In the present study, we investigated TLR-5-mediated A20 expression and its role in intestinal epithelial cells (IECs) during inflammation. HCT-15 and HT-29 cells were stimulated with flagellin, then the expressions of A20, interleukin-1 receptor-associated kinase (IRAK-M) and Tollip were evaluated using RNase protection assay. Furthermore, experimental colitis was induced in tlr4-deficient CH3/HeJ mice by administration of dextran sodium sulphate (DSS), then flagellin was injected anally, and the colonic expression of A20 was examined by real-time polymerase chain reaction (PCR) and immunohistochemistry. To confirm flagellin-induced expression of A20, we employed an organ culture system. The role of A20 in flagellin-induced tolerance induction was evaluated in vitro, using a gene knock-down method targeting A20. A20 expression increased rapidly and peaked at 1 h after flagellin stimulation in cultured IECs, then declined gradually to the basal level. In vivo, anal injection of flagellin induced epithelial expression of A20 in injured colonic tissue, whereas flagellin did not cause a significant increase in A20 expression in non-injured normal tissue, which was also confirmed in vitro using the organ culture system. Gene knock-down using A20 siRNA did not influence tolerance induced by restimulation with flagellin. A20 is an early response negative regulator of TLR-5 signalling in IECs that functions during intestinal inflammation. Our results provide new insights into the negative feedback regulation of TLR-5 signalling that maintains the innate immune system in the gut.


Assuntos
Células Epiteliais/metabolismo , Inflamação/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas Nucleares/metabolismo , Receptor 5 Toll-Like/metabolismo , Animais , Linhagem Celular Tumoral , Células Cultivadas , Quimiocina CXCL2/genética , Quimiocina CXCL2/metabolismo , Cisteína Endopeptidases/genética , Cisteína Endopeptidases/metabolismo , Proteínas de Ligação a DNA , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/patologia , Flagelina/administração & dosagem , Citometria de Fluxo , Expressão Gênica/efeitos dos fármacos , Células HT29 , Humanos , Imuno-Histoquímica , Inflamação/patologia , Intestinos/patologia , Peptídeos e Proteínas de Sinalização Intracelular/genética , Lipopolissacarídeos/administração & dosagem , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Proteínas Nucleares/genética , Interferência de RNA , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/efeitos dos fármacos , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo , Receptor 5 Toll-Like/genética , Proteína 3 Induzida por Fator de Necrose Tumoral alfa
11.
Clin Exp Immunol ; 162(2): 348-61, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21077278

RESUMO

Single immunoglobulin (Ig) interleukin-1R-related molecule (SIGIRR) is an Ig-like membrane protein critical for negative regulation of Toll-like receptor (TLR)-4-mediated signalling. We investigated SIGIRR expression and its regulation mechanism in intestinal epithelial cells (IECs) during inflammation. Endoscopic biopsy specimens were obtained from active and inactive colonic mucosa of ulcerative colitis (UC) patients, then SIGIRR expression was examined using real-time polymerase chain reaction (PCR) and immunohistochemistry (IH). Mice experimental colitis models were established by administrations of sulphonic acid (TNBS) and dextran sodium sulphate (DSS), and epithelial expression of SIGIRR was examined using real-time PCR, IH and flow cytometry. The effects of lipopolysaccharide (LPS) and tumour necrosis factor (TNF)-α on SIGIRR expression were evaluated in vitro using cultured IECs. To elucidate SIGIRR expression regulation in IECs, binding ability of the transcription factor SP1 at the responsive element of the SIGIRR promoter was examined using gel-shift and chromatin immunoprecipitation (ChIP) assays. In human colonic samples, SIGIRR was expressed mainly in IECs at levels significantly higher in inactive compared to active mucosa. In the mice, SIGIRR colonic expression decreased rapidly after colitis development and returned gradually to basal levels. Experimental colitis-mediated down-regulation of SIGIRR in IECs was also confirmed by IH and flow cytometry results. Further, inflammatory conditions induced by TLR ligands and TNF-α caused significant down-regulation of SIGIRR expression in IECs, which was dependent upon decreased SP1 binding at the responsive element of the SIGIRR promoter. We found that SIGIRR is expressed in IECs and serves as a negative regulator to maintain gut innate immunity, which is down-regulated during inflammation by inhibition of an SP1-mediated pathway.


Assuntos
Colite/metabolismo , Regulação para Baixo/imunologia , Células Epiteliais/metabolismo , Mucosa Intestinal/metabolismo , Receptores de Interleucina-1/metabolismo , Adulto , Idoso , Animais , Linhagem Celular Tumoral , Colite/induzido quimicamente , Colite Ulcerativa/metabolismo , Colo/metabolismo , Modelos Animais de Doenças , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/genética , Regulação da Expressão Gênica/imunologia , Humanos , Inflamação/metabolismo , Intestino Grosso/metabolismo , Lipopolissacarídeos/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Pessoa de Meia-Idade , NF-kappa B/metabolismo , Regiões Promotoras Genéticas/genética , Ligação Proteica/genética , RNA Interferente Pequeno/genética , Receptores de Interleucina-1/genética , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/imunologia , Fator de Transcrição Sp1/metabolismo , Organismos Livres de Patógenos Específicos , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/imunologia , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/farmacologia , Adulto Jovem
12.
Endoscopy ; 42(2): 104-8, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19967631

RESUMO

BACKGROUND AND STUDY AIMS: Unsedated transnasal small-caliber esophagogastroduodenoscopy (EGD) has been used to examine the upper gastrointestinal tract with proven feasibility and tolerability. However, a limitation of transnasal EGD is the poor lens-cleansing function of the scope due to the small-caliber water-jet nozzle. Therefore, this trial was designed to evaluate the cleansing effect of oolong tea for transnasal small-caliber EGD. PATIENTS AND METHODS: Oolong tea (O), barley tea (B), and distilled water (W) were prepared as washing solutions for endoscopic lenses. Study I: after the lenses were soiled by lard oil, they were washed with one of the three washing solutions, and the image quality of photographs was judged. Study II: 982 patients who were due to undergo transnasal EGD were enrolled and randomly assigned to the O-, B-, or W-groups. The level of lens cleansing, the overall time required for endoscopy, and the volume of washing solution used were measured. RESULTS: Study I: the image quality of photographs taken with lenses washed with oolong tea was significantly superior to that associated with other solutions. Study II: the level of lens cleansing in the O-group was significantly superior to that of the B- and W-groups ( P < 0.001). The volume of solution used for lens cleansing in the O-group was significantly smaller than that in the W-group ( P < 0.05). Endoscopic examination times in the O-group were shorter than those in the B- and W-groups ( P < 0.05). CONCLUSIONS: In transnasal small-caliber EGD, oolong tea instead of water as a washing solution for endoscopic lens cleansing is useful to maintain good visibility.


Assuntos
Bebidas , Detergentes/farmacologia , Desinfecção/métodos , Endoscópios Gastrointestinais , Lentes , Chá , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Nariz , Estudos Prospectivos
13.
J Int Med Res ; 38(4): 1473-83, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20926021

RESUMO

This two-way crossover study investigated possible differences between the proton pump inhibitors, omeprazole and rabeprazole, in their effect on gastric acid secretion in Japanese subjects with differing cytochrome P450, family 2, subfamily C, polypeptide 19 (CYP2C19) genotypes. A total of 23 Helicobacter pylori-negative healthy volunteers received omeprazole 20 mg/day and rabeprazole 10 mg/day. Each drug treatment was given for a continuous 7-day period allocated in random order, with an interval of at least 1 week between drug treatment periods to allow for wash-out. Intragastric pH was measured on days 1 and 7. Overall median intragastric pH levels at 7 and 8 h after the first administration were significantly higher with omeprazole. There was no significant difference in intragastric pH in homozygous extensive metabolizers, whereas intragastric pH was significantly higher with omeprazole in combined data from heterozygous extensive metabolizers and poor metabolizers at 6, 7 and 8 h after the first drug administration. There were no significant differences in intragastric pH between omeprazole and rabeprazole irrespective of genotype on day 7 of administration. In conclusion, on day 1 the time to onset of the antisecretory action of 20 mg/day omeprazole was more rapid than that of 10 mg/day rabeprazole in Japanese individuals who have a higher incidence of the CYP2C19 poor metabolizer genotype, however by day 7 no difference in antisecretory effect was found, regardless of genotype.


Assuntos
2-Piridinilmetilsulfinilbenzimidazóis/farmacologia , Hidrocarboneto de Aril Hidroxilases/genética , Povo Asiático/genética , Omeprazol/farmacologia , Inibidores da Bomba de Prótons/farmacologia , 2-Piridinilmetilsulfinilbenzimidazóis/administração & dosagem , Adulto , Estudos Cross-Over , Citocromo P-450 CYP2C19 , Feminino , Genótipo , Helicobacter pylori/efeitos dos fármacos , Helicobacter pylori/fisiologia , Humanos , Concentração de Íons de Hidrogênio/efeitos dos fármacos , Japão , Masculino , Omeprazol/administração & dosagem , Inibidores da Bomba de Prótons/administração & dosagem , Rabeprazol , Adulto Jovem
14.
Kyobu Geka ; 63(8 Suppl): 740-3, 2010 Jul.
Artigo em Japonês | MEDLINE | ID: mdl-20715451

RESUMO

The stomach as a conduit after esophagectomy is preferred to the colon because it is much simpler to prepare and involves only 1 anastomosis. The following principles should be followed in preparing the stomach as an esophageal substitute: the complete removal of lymphatics within the left gastric area, and careful preservation of the gastric intramural vascular network. The line of resection, where the vessels of the left gastric area enter the gastric wall, should be cautiously decided. Border between the left and right gastric area of the lesser curvature is identified by the courses of these arteries. The 1st GIA should be inserted slightly toward the caudal side, and the 2nd GIA should be fired along the resection-line. The final GIA should be advanced to the highest point. The space beneath the sternum in the anterior mediastinum is easily created with minimal blood loss. The space is initially created by blunt finger dissection through the abdominal and cervical incisions, and further developed by insertion of a flat malleable intestinal retractor with a hole on 1 side, which is useful for elevating the esophageal substitute without a twist.


Assuntos
Esofagoplastia/métodos , Neoplasias Esofágicas/cirurgia , Esofagectomia , Humanos
15.
Gut ; 58(5): 620-8, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19136512

RESUMO

BACKGROUND AND AIMS: The mechanism of transformation to intestinal metaplasia in Barrett's oesophagus has not been clarified. We previously reported that bile acids activate the Cdx2 promoter via nuclear factor kappa B (NF-kappaB) and stimulate production of Cdx2 protein in oesophageal keratinocytes with a resulting production of intestinal type mucin. In addition to Cdx2, Cdx1 may play an important role in the development of Barrett's oesophagus. Therefore, we studied the direct effects of bile acids on the expression of Cdx1 as well as the precise mechanisms of Cdx1 expression in cultured oesophageal squamous epithelial cells. Furthermore, we investigated the relationship between Cdx1 and Cdx2 expression in cultured oesophageal squamous epithelial cells. METHODS: A rat model of Barrett's oesophagus was produced by anastomosing the oesophagus and jejunum. The expression of Cdx1 was investigated by immunohistochemistry, while the response of that expression to bile acids was studied using a Cdx1 promoter luciferase assay. In addition, oesophageal squamous epithelial cells were transfected with a Cdx1 or Cdx2 expression vector, after which their possible transformation to intestinal-type epithelial cells was investigated. RESULTS: In our Barrett's rat model, the metaplastic epithelium and adjoining squamous epithelium strongly expressed Cdx1. Further, the bile acids mixture dose-dependently increased Cdx1 promoter activity and Cdx1 protein in oesophageal epithelial cells. Transfection of the Cdx1 expression vector in cultured oesophageal epithelial cells induced production of Cdx2 protein. CONCLUSION: Bile acid-induced sequential expression of Cdx1 followed by Cdx2 may have an important role in the development of Barrett's epithelium.


Assuntos
Esôfago de Barrett/genética , Ácidos e Sais Biliares/farmacologia , Genes Homeobox/genética , Proteínas de Homeodomínio/metabolismo , Animais , Esôfago de Barrett/metabolismo , Esôfago de Barrett/patologia , Fator de Transcrição CDX2 , Células Epiteliais/metabolismo , Esôfago/metabolismo , Esôfago/patologia , Regulação da Expressão Gênica/efeitos dos fármacos , Genes Reporter , Proteínas de Homeodomínio/genética , Imuno-Histoquímica , Masculino , Metaplasia/genética , Metaplasia/metabolismo , Mucina-2/genética , Mucina-2/metabolismo , Ratos , Ratos Wistar , Fatores de Transcrição/metabolismo , Ativação Transcricional/efeitos dos fármacos
16.
Nat Commun ; 11(1): 2888, 2020 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-32514054

RESUMO

Solids with competing interactions often undergo complex phase transitions with a variety of long-periodic modulations. Among such transition, devil's staircase is the most complex phenomenon, and for it, CeSb is the most famous material, where a number of the distinct phases with long-periodic magnetostructures sequentially appear below the Néel temperature. An evolution of the low-energy electronic structure going through the devil's staircase is of special interest, which has, however, been elusive so far despite 40 years of intense research. Here, we use bulk-sensitive angle-resolved photoemission spectroscopy and reveal the devil's staircase transition of the electronic structures. The magnetic reconstruction dramatically alters the band dispersions at each transition. Moreover, we find that the well-defined band picture largely collapses around the Fermi energy under the long-periodic modulation of the transitional phase, while it recovers at the transition into the lowest-temperature ground state. Our data provide the first direct evidence for a significant reorganization of the electronic structures and spectral functions occurring during the devil's staircase.

17.
J Cell Biol ; 150(2): 335-47, 2000 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-10908576

RESUMO

Nitric oxide is a chemical messenger implicated in neuronal damage associated with ischemia, neurodegenerative disease, and excitotoxicity. Excitotoxic injury leads to increased NO formation, as well as stimulation of the p38 mitogen-activated protein (MAP) kinase in neurons. In the present study, we determined if NO-induced cell death in neurons was dependent on p38 MAP kinase activity. Sodium nitroprusside (SNP), an NO donor, elevated caspase activity and induced death in human SH-SY5Y neuroblastoma cells and primary cultures of cortical neurons. Concomitant treatment with SB203580, a p38 MAP kinase inhibitor, diminished caspase induction and protected SH-SY5Y cells and primary cultures of cortical neurons from NO-induced cell death, whereas the caspase inhibitor zVAD-fmk did not provide significant protection. A role for p38 MAP kinase was further substantiated by the observation that SB203580 blocked translocation of the cell death activator, Bax, from the cytosol to the mitochondria after treatment with SNP. Moreover, expressing a constitutively active form of MKK3, a direct activator of p38 MAP kinase promoted Bax translocation and cell death in the absence of SNP. Bax-deficient cortical neurons were resistant to SNP, further demonstrating the necessity of Bax in this mode of cell death. These results demonstrate that p38 MAP kinase activity plays a critical role in NO-mediated cell death in neurons by stimulating Bax translocation to the mitochondria, thereby activating the cell death pathway.


Assuntos
Apoptose/fisiologia , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Neurônios/metabolismo , Óxido Nítrico/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2 , Proteínas Proto-Oncogênicas/metabolismo , Translocação Genética/fisiologia , Caspases/metabolismo , Córtex Cerebral/citologia , Córtex Cerebral/metabolismo , Humanos , Neuroblastoma , Nitroprussiato/farmacologia , Células Tumorais Cultivadas , Proteína X Associada a bcl-2 , Proteínas Quinases p38 Ativadas por Mitógeno
18.
Science ; 289(5477): 257-8, 2000 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-10917851

RESUMO

It has been assumed that the new members of the p53 protein family, p63 and p73, would have the same job as p53, namely, forcing cells to die if they or their DNA is damaged. Now, as Morrison and Kinoshita explain in their Perspective, one particular form of p73 has been found to be a survival factor rather than a death factor for sympathetic neurons during development (Pozniak et al.).


Assuntos
Proteínas de Ligação a DNA/fisiologia , Neurônios/fisiologia , Proteínas Nucleares/fisiologia , Sistema Nervoso Simpático/crescimento & desenvolvimento , Animais , Apoptose , Proteínas de Ligação a DNA/genética , Genes Supressores de Tumor , Camundongos , Proteínas Nucleares/genética , Sistema Nervoso Simpático/citologia , Sistema Nervoso Simpático/fisiologia , Proteína Tumoral p73 , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/fisiologia , Proteínas Supressoras de Tumor
19.
Dis Esophagus ; 22(5): 427-33, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19191859

RESUMO

Refractory strictures of esophagogastric anastomosis caused by leakage following an esophagectomy are a severe complication, for which either repeated balloon dilations or bougies are not necessarily effective. In such a case, surgical repair is quite difficult because the esophageal substitute such as the stomach or colon is usually located in the mediastinum and severely adhesive to the neighboring organs. Furthermore, in case the resected stricture is too long for direct re-anastomosis to be performed, a free jejunal graft or a new esophageal substitute should be prepared. This paper proposes a procedure for the re-reconstruction of refractory stricture in the case of a retrosternal reconstruction with a gastric conduit, which frequently employs pull-up route. The anterior plate of the manubrium was divided medially from the notch to the symphysis with the sternal saw. The manubrium is then removed, bite by bite, like breaking up rocks, with a bone rongeur forceps, starting with the anterior plate, then the posterior plate, from upper median part to the lower and lateral part of the sternum until it reaches the symphysis and the sternoclavicular and the sternocostal joints. It is safer to destroy the manubrium little by little from the anterior side so that the posterior periosteum, which is likely to adhere tightly to the gastric conduit, can be preserved. After the manubrium is almost completely resected and the posterior periosteum of the manubrium is preserved, a median longitudinal incision is carefully made on the periosteum so as not to damage the gastric conduit that may be adhesive to the periosteum. The periosteum was gradually opened bilaterally separating the periostium and the gastric conduit. Although gastroenterological surgeons may hesitate to remove the manubrium, removing the manubrium and preserving the posterior periosteum make it possible to avoid injuring the gastric conduit and to provide a wide view around the stenosis for safely resecting the anastomotic stricture. Furthermore, this procedure allows direct re-anastomosis between the cervical esophagus and the gastric conduit without a complicated reconstruction such as a free jejunal graft. This procedure is strongly recommended as an alternative option so that a second reconstruction can be performed both safely and steadily.


Assuntos
Anastomose Cirúrgica/efeitos adversos , Estenose Esofágica/cirurgia , Esofagectomia , Procedimentos de Cirurgia Plástica/efeitos adversos , Complicações Pós-Operatórias , Cateterismo/métodos , Neoplasias Esofágicas/cirurgia , Esofagoscopia , Esôfago/cirurgia , Humanos , Masculino , Manúbrio/cirurgia , Microcirurgia/métodos , Pessoa de Meia-Idade , Periósteo/cirurgia , Complicações Pós-Operatórias/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Recidiva , Reoperação , Costelas/cirurgia , Articulação Esternoclavicular/cirurgia , Esterno/cirurgia , Estômago/cirurgia , Aderências Teciduais/etiologia , Aderências Teciduais/cirurgia
20.
Oncogene ; 26(3): 349-59, 2007 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-16909126

RESUMO

Reg I (regenerating gene product I) is a growth factor that plays a central role in the generation and regeneration of the gastric mucosal architecture. On the other hand, mouse Reg I mRNA is expressed at the highest levels in the small intestine among the gastrointestinal tissues. In the current study, with the aim to clarify the role of Reg I protein in the small intestine, the temporal and spatial pattern of Reg I expression and the phenotype of Reg I-knockout mice in the tissue were examined. In the wild-type mice, immunohistochemistry localized Reg I protein expression in absorptive cells located in the lower half of the intestinal villi. Reg I expression was undetectable until embryonic day 13 (E13), when the fetal intestine still lacks villous structure; however, it dramatically increased at E17 along with the formation and maturation of the fetal intestinal villi. In the small intestine of the adult Reg I-knockout mice, less densely packed, round-shaped aberrant morphology of the absorptive cells was observed light microscopically, and electron microscopical examination revealed a strikingly loose connection of these cells to the basement membrane. Antiproliferating cell nuclear antigen staining and anti-Ki67 staining demonstrated the marked decrease in the number of proliferating cells in the small intestinal mucosa of the knockout mice. The cell migration speed visualized by one shot labeling of 5-bromodeoxyuridine was significantly slower in the knockout mice. These phenotypes of Reg I-knockout mice emerged, in accordance with the temporal pattern of Reg I expression described above, from E17. Reg I was considered to be a regulator of cell growth that is required to generate and maintain the villous structure of the small intestine.


Assuntos
Proliferação de Células , Mucosa Intestinal/citologia , Intestino Delgado/citologia , Litostatina/fisiologia , Microvilosidades/ultraestrutura , Animais , Processos de Crescimento Celular , Movimento Celular , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Mucosa Intestinal/ultraestrutura , Intestino Delgado/ultraestrutura , Litostatina/genética , Masculino , Camundongos , Camundongos Endogâmicos ICR , Camundongos Knockout , Fenótipo , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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