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2.
Sci Rep ; 9(1): 9791, 2019 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-31278359

RESUMO

Low-density polyethylene (LDPE) has short-chain branch (SCB) and long-chain branch (LCB). In particular, the influence of the structure of LCBs on polymer properties is remarkable; however, it has been difficult to precisely analyze LCB structures. In this study, we measured the chain length of LCBs and the distance between branch points of LDPE by atomic force microscopy. Consequently, three LCBs were confirmed in a main chain of 162 nm, and their length were measured as 10, 31, and 18 nm. The positions of the LCBs were 33, 70, and 78 nm from the main-chain end.

3.
Nihon Hinyokika Gakkai Zasshi ; 110(1): 56-59, 2019.
Artigo em Japonês | MEDLINE | ID: mdl-31956221

RESUMO

Herein we report the confirmation of fungus balls (circular collections of C.tropicalis) during a transurethral ureterolithotomy, which is as far as we know the first reported instance. A-61-year old man was referred to the urology department with bilateral ureteral calculi. Initially a transurethral ureterolithotomy was attempted but residual stones existed. During the second operation, we found numerous white fluffy material in the renal pelvis. Because of them, we were unable to have a clear field of vision to complete operation. During the third operation, we found the fungus balls again and cultured them. Cultures yielded C.tropicalis.


Assuntos
Candida tropicalis , Candidíase/complicações , Litotripsia , Ureter , Urolitíase/complicações , Urolitíase/terapia , Humanos , Achados Incidentais , Masculino , Pessoa de Meia-Idade
4.
Artigo em Inglês | MEDLINE | ID: mdl-28475958

RESUMO

The internal structure of self-assembled monolayers (SAMs) such as 3-aminopropyltriethoxysilane (APTES) fabricated on a glass substrate is difficult to characterize and analyze at nanometer level. In this study, we employed surface-enhanced Raman spectroscopy (SERS) to study the internal molecular structure of APTES SAMs. The sample APTES SAMs were deposited with Ag nanoparticles to enhance the Raman signal and to obtain subtler structure information, which were supported by density functional theory calculations. In addition, in order to carry out high-resolution analysis, especially for vertical direction, a fine piezo electric positioner was used to control the depth scanning with a step of 0.1nm. We measured and distinguished the vertical Raman intensity variations of specific groups in APTES, such as Ag/NH2, CH2, and SiO, with high resolution. The interfacial bond at the two interfaces of Ag-APTES and APTES-SiO2 was identified. Moreover, APTES molecule orientation was demonstrated to be inhomogeneous from frequency shift.

5.
Hinyokika Kiyo ; 62(10): 549-552, 2016 Oct.
Artigo em Japonês | MEDLINE | ID: mdl-27919131

RESUMO

Foreign body in the bladder is a relatively rare case. We encountered two cases of foreign bodies in the bladder after gynecological surgery. Case 1 was a 72-year-old woman. When she was 70 years old,an operation for her pelvic organ prolapse was performed. She visited our hospital because of discomfort in urination. We performed a transurethral lithotripsy of the bladder stone and detected a foreign body,and it was an anchor used for the Tissue Fixation System(TFS)operation (a pelvic organ prolapse operation). Case 2 was a 34-year-old woman. She delivered a baby by Caesarean section when she was 30 years old. She visited our hospital because of recurring urinary tract infection. The ultrasound examination of the bladder showed high echoic area in the posterior bladder wall. The cystoscope examination showed a small black foreign body that was protruding from the posterior wall of the bladder. The foreign body in the bladder was a surgical suture. The component of the suture was similar to silk. The foreign body in the bladder may have been the cause of infection. Artificial material used for an operation of an organ in the pelvic area sometimes slips into the bladder and causes inflammation. If a patient had undergone an operation for an organ in the pelvic area in the past,and there is recurring urinary tract infection,the presence of a foreign body in the bladder should be suspected.


Assuntos
Corpos Estranhos/cirurgia , Adulto , Idoso , Cesárea , Feminino , Humanos , Recidiva , Infecções Urinárias , Micção
6.
Hinyokika Kiyo ; 62(2): 83-6, 2016 Feb.
Artigo em Japonês | MEDLINE | ID: mdl-27018411

RESUMO

The patient was a 75 year-old male. Noticing areas of hardening in the lower abdomen, and consequently feelings of systemic fatigue and difficulty in walking, the patient visited a clinic and was diagnosed with kidney failure prior to the visit to our clinic. Computed tomography and magnetic resonance imaging showed thickness of the rectus abdominis muscle and the bladder wall, and bilateral hydronephrosis was also identified. As no explicit tumor was identified in the bladder, the patient underwent biopsies of the abdominal wall and bladder membrane mucous, and was diagnosed with a plasmacytoid urothelial carcinoma primarily developed in the bladder. The patient displayed a poor general state of health and died five months after the diagnosis. It is known that plasmacytoid urothelial carcinomas progress rapidly and the prognosis is poorer than for the micropapillary variant. It is important to obtain a tissue specimen in the early stage of this disease because there are cases in which no explicit tumor can be identified. Furthermore, the value of carbohydrate antigen (CA) 19-9 of the patient was much higher than would be expected as normal at the first visit. It kept rising during the follow-up and was useful as a marker to indicate the progress of the disease.


Assuntos
Parede Abdominal/patologia , Neoplasias da Bexiga Urinária/patologia , Urotélio/patologia , Idoso , Evolução Fatal , Humanos , Imageamento por Ressonância Magnética , Masculino , Imagem Multimodal , Tomografia Computadorizada por Raios X
7.
PLoS One ; 10(6): e0129964, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26067913

RESUMO

Altered protein expression and phosphorylation are common events during malignant transformation. These perturbations have been widely explored in the context of E-cadherin cell-cell adhesion complexes, which are central in the maintenance of the normal epithelial phenotype. A major component of these complexes is p120 catenin (p120), which binds and stabilizes E-cadherin to promote its adhesive and tumor suppressing function. However, p120 is also an essential mediator of pro-tumorigenic signals driven by oncogenes, such as Src, and can be phosphorylated at multiple sites. Although alterations in p120 expression have been extensively studied by immunohistochemistry (IHC) in the context of tumor progression, little is known about the status and role of p120 phosphorylation in cancer. Here we show that tyrosine and threonine phosphorylation of p120 in two sites, Y228 and T916, is elevated in renal and breast tumor tissue samples. We also show that tyrosine phosphorylation of p120 at its N-terminus, including at the Y228 site is required for its pro-tumorigenic potential. In contrast, phosphorylation of p120 at T916 does not affect this p120 function. However, phosphorylation of p120 at T916 interferes with epitope recognition of the most commonly used p120 antibody, namely pp120. As a result, this antibody selectively underrepresents p120 levels in tumor tissues, where p120 is phosphorylated. Overall, our data support a role of p120 phosphorylation as a marker and mediator of tumor transformation. Importantly, they also argue that the level and localization of p120 in human cancer tissues immunostained with pp120 needs to be re-evaluated.


Assuntos
Neoplasias da Mama/patologia , Carcinoma de Células Renais/patologia , Cateninas/metabolismo , Transformação Celular Neoplásica/patologia , Neoplasias Renais/patologia , Fosfoproteínas/metabolismo , Western Blotting , Neoplasias da Mama/metabolismo , Carcinoma de Células Renais/metabolismo , Transformação Celular Neoplásica/metabolismo , Feminino , Humanos , Técnicas Imunoenzimáticas , Imunoprecipitação , Neoplasias Renais/metabolismo , Fosforilação , Ligação Proteica , Serina/metabolismo , Treonina/metabolismo , Análise Serial de Tecidos , Células Tumorais Cultivadas , Tirosina/metabolismo , delta Catenina
8.
BMC Cancer ; 15: 338, 2015 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-25929438

RESUMO

BACKGROUND: We analyzed the relationship between prostate cancer outcomes and pretreatment clinical factors and developed a prognostic nomogram of overall survival (OS) of patients with bone metastasis. METHODS: From 1993 to 2011, 463 consecutive patients were treated for bone-metastatic prostate cancer. Data sets from 361 patients were used to develop a nomogram (training data), and data sets of 102 patients were used for validation of the nomogram (validation data). Using the external validation data set, the nomogram was assessed for discriminatory ability, and the predictions were assessed for calibration accuracy by plotting actual survival against predicted risk. RESULTS: Of the 361 patients in the training data set, 205 (56.8%) patients died, 169 (46.8%) deaths of which were due to prostate cancer. The median follow-up period was 55.2 months. In the multivariate analysis, patient age, serum prostate-specific antigen level, clinical T stage, extent of disease on bone scan, and biopsy Gleason sum were independent prognostic factors. We developed a prognostic model comprising these five factors for patients with bone-metastatic prostate cancer. This nomogram can be used to estimate 1-, 3-, and 5-year survival probability. External validation of this model using 102 validation data sets showed reasonable accuracy (concordance index, 0.719). CONCLUSION: Our pretreatment prognostic nomogram might be useful for Japanese patients with bone-metastatic prostate cancer.


Assuntos
Neoplasias Ósseas/patologia , Prognóstico , Neoplasias da Próstata/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Ósseas/sangue , Neoplasias Ósseas/secundário , Intervalo Livre de Doença , Humanos , Japão , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Nomogramas , Antígeno Prostático Específico/sangue , Prostatectomia , Neoplasias da Próstata/sangue , Neoplasias da Próstata/cirurgia
9.
Hinyokika Kiyo ; 60(9): 431-4, 2014 Sep.
Artigo em Japonês | MEDLINE | ID: mdl-25293796

RESUMO

The patient was a 78-year-old female. At the age of 76, the patient had undergone computed tomographic scanning for left lower abdominal pain. A retroperitoneal mass was detected on the right side of the abdomen. The patient had been subject to right nephrectomy due to renal calculus at the age of 33. With Doppler echocardiography and magnetic resonance imaging (MRI), based on the nephrectomy the patient was diagnosed with a renal arteriovenous fistula developed in the right renal bed. Following the wishes of the patient a follow-up examination was conducted. Because of poor heart condition and renal dysfunction, percutaneous arterial embolization was performed. After the embolization, the heart condition and renal dysfunction indicators improved and the blood flow in the arteriovenous fistula disappeared. Cases of renal arteriovenous fistulae after nephrectomy are rare, with only 90 reported worldwide, and percutaneous arterial embolization has been used as the first choice of treatment in recent years.


Assuntos
Fístula Arteriovenosa/terapia , Embolização Terapêutica , Rim/irrigação sanguínea , Artéria Renal/diagnóstico por imagem , Idoso , Fístula Arteriovenosa/diagnóstico por imagem , Embolização Terapêutica/métodos , Feminino , Humanos , Nefrectomia , Tomografia Computadorizada por Raios X
10.
Hinyokika Kiyo ; 59(4): 213-6, 2013 Apr.
Artigo em Japonês | MEDLINE | ID: mdl-23635455

RESUMO

We retrospectively evaluated 23 patients who had been administered pirarubicin by intravesical instillation once weekly for 5 weeks, after undergoing surgery for upper urinary tract cancer between May 2003 and October 2008. We compared their clinical records with those of 19 patients with upper urinary tract cancer subjected to nephroureterectomy between 1998 and 2008, and who did not receive intravesical instillation of pirarubicin. This prophylactic therapy was well tolerated and contributed to reduce the rate of bladder recurrence. The non-recurrence rate at 2 years was 87.0% in the instillation group and 68.4% in the non-instillation group (P=0.0025). The overall analysis of the study population did not reveal any statistically significant risk factors of bladder recurrence.


Assuntos
Antineoplásicos/administração & dosagem , Doxorrubicina/análogos & derivados , Recidiva Local de Neoplasia/prevenção & controle , Nefrectomia , Ureterocele , Neoplasias da Bexiga Urinária/prevenção & controle , Neoplasias Urológicas/cirurgia , Administração Intravesical , Idoso , Idoso de 80 Anos ou mais , Doxorrubicina/administração & dosagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
11.
Case Rep Pathol ; 2013: 973865, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23607027

RESUMO

The juxtaglomerular cell tumor (JGCT) is a rare renal tumor characterized by excessive renin secretion causing intractable hypertension and hypokalemia. However, asymptomatic nonfunctioning JGCT is extremely rare. Here, we report a case of nonfunctioning JGCT in a 31-year-old woman. The patient presented with a left renal tumor without hypertension or hypokalemia. Under a clinical diagnosis of renal cell carcinoma, radical nephrectomy was performed. The tumor was located in the middle portion adjacent to the renal pelvis, measuring 2 cm in size. Pathologically, the tumor was composed of cuboidal cells forming a solid arrangement, immunohistochemically positive for renin. Based on these findings, the tumor was diagnosed as JGCT. In cases with hyperreninism, preoperative diagnosis of JGCT is straightforward but difficult in nonfunctioning case. Generally, JGCT presents a benign biological behavior. Therefore, we should take nonfunctioning JGCT into the differential diagnoses for renal tumors, especially in younger patients to avoid excessive surgery.

12.
Hinyokika Kiyo ; 59(2): 141-3, 2013 Feb.
Artigo em Japonês | MEDLINE | ID: mdl-23552761

RESUMO

A 45-year-old man visited our emergency room with left inguinal pain, mass and high-grade fever. Emergency surgery was performed with a primary diagnosis of left inguinal hernia. Although there was no hernia, there was a mass involving the spermatic cord in the left inguinal canal. We performed high orchiectomy because of the possibility of malignancy. Pathological findings showed eosinophilic infiltration in the mass lesion. An allergic inflammation was suspected to have occurred in the spermatic cord. His postoperative course was good.


Assuntos
Eosinofilia/diagnóstico , Doenças dos Genitais Masculinos/diagnóstico , Hérnia Inguinal/diagnóstico , Cordão Espermático , Diagnóstico Diferencial , Humanos , Masculino , Pessoa de Meia-Idade
13.
Int J Clin Oncol ; 18(3): 472-7, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22491982

RESUMO

BACKGROUND: To ascertain the anti-tumor effect of zoledronic acid (ZOL) treatment on clinical outcomes in patients with bone metastatic prostate cancer, we examined the effect of ZOL started simultaneously with hormonal therapy as initial treatment in these patients. METHODS: Forty-seven patients with bone-metastatic prostate cancer who received a luteinizing hormone releasing-hormone (LHRH) analogue and an anti-androgen [maximal androgen blockade (MAB)] were assigned to receive ZOL (4 mg intravenous administration every month for 2 years). The time to progression (TTP) of the prostate-specific antigen (PSA), the overall survival (OS), and the rate of PSA decrease in patients with MAB and ZOL treatment (ZOL group) were compared with these parameters in patients who received only MAB at one institute as a control group (non-ZOL group). RESULTS: Although the nadir PSA level and the rate of PSA normalization showed no significant differences between the ZOL and non-ZOL groups, the time to nadir PSA in the ZOL group was significantly shorter than that in the non-ZOL group (P < 0.05, Mann-Whitney U-test). There was a significant difference in TTP (P = 0.017, log-rank test) between the ZOL and non-ZOL groups, and statistically significant differences in TTP and OS between the ZOL and non-ZOL groups (P = 0.044 and 0.035, log-rank test) were recognized particularly in patients with advanced disease (extension of disease, grade 3 and 4). CONCLUSIONS: Simultaneous administration of ZOL and MAB as initial treatment delayed TTP in bone-metastatic prostate cancer patients. Initial treatment with ZOL has the possibility of anti-tumor activity to delay disease progression.


Assuntos
Neoplasias Ósseas/tratamento farmacológico , Difosfonatos/administração & dosagem , Imidazóis/administração & dosagem , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos Hormonais/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias Ósseas/patologia , Neoplasias Ósseas/secundário , Intervalo Livre de Doença , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Neoplasias da Próstata/sangue , Neoplasias da Próstata/patologia , Ácido Zoledrônico
14.
Biomacromolecules ; 12(11): 3982-8, 2011 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-21928815

RESUMO

Three holocelluloses (i.e., cellulose and hemicellulose fractions) are prepared from softwood and hardwood by the Wise method. These holocelluloses completely dissolve in 8% lithium chloride/1,3-dimethyl-2-imidazolidinone (LiCl/DMI) after an ethylenediamine (EDA) pretreatment. After diluting the holocellulose solutions to 1% LiCl/DMI, they are subjected to size-exclusion chromatography/multiangle laser-light scattering/photodiode array (SEC-MALLS-PDA) analysis. All holocelluloses exhibit bimodal molecular weight distributions primarily due to high-molecular-weight (HMW) cellulose and low-molecular-weight hemicellulose fractions. Plots of molecular weight vs root-mean-square radius obtained by SEC-MALLS analysis revealed that all the wood celluloses comprise dense conformations in 1% LiCl/DMI. In contrast, bacterial cellulose, which was used as a pure cellulose model, has a random coil conformation as a linear polymer. These results show that both softwood and hardwood HMW celluloses contain branched structures, which are probably present on crystalline cellulose microfibril surfaces. These results are consistent with those obtained by permethylation analysis of wood celluloses.


Assuntos
Celulose/química , Cloreto de Lítio/química , Solventes/química , Madeira/química , Configuração de Carboidratos , Carboidratos/química , Celulose/ultraestrutura , Cryptomeria/química , Etilenodiaminas/química , Eucalyptus/química , Fagus/química , Imidazolidinas/química , Lasers , Luz , Peso Molecular , Espalhamento de Radiação , Madeira/ultraestrutura , Difração de Raios X
15.
J Biol Chem ; 285(25): 19153-61, 2010 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-20395297

RESUMO

The Rac1b splice isoform contains a 19-amino acid insertion not found in Rac1; this insertion leads to decreased GTPase activity and reduced affinity for GDP, resulting in the intracellular predominance of GTP-bound Rac1b. Here, using co-precipitation and proteomic methods, we find that Rac1b does not bind to many common regulators of Rho family GTPases but that it does display enhanced binding to SmgGDS, RACK1, and p120 catenin (p120(ctn)), proteins involved in cell-cell adhesion, motility, and transcriptional regulation. We use molecular modeling and structure analysis approaches to determine that the interaction between Rac1b and p120(ctn) is dependent upon protein regions that are predicted to be unstructured in the absence of molecular complex formation, suggesting that the interaction between these two proteins involves coupled folding and binding. We also find that directed cell movement initiated by Rac1b is dependent upon p120. These results define a distinct binding functionality of Rac1b and provide insight into how the distinct phenotypic program activated by this protein may be implemented through molecular recognition of effectors distinct from those of Rac1.


Assuntos
Aminoácidos/química , Cateninas/química , Proteínas rac1 de Ligação ao GTP/química , Processamento Alternativo , Sequência de Aminoácidos , Animais , Adesão Celular , Movimento Celular , Células Epiteliais/citologia , Camundongos , Dados de Sequência Molecular , Fenótipo , Ligação Proteica , Isoformas de Proteínas , Transcrição Gênica , delta Catenina
16.
Hinyokika Kiyo ; 56(1): 45-8, 2010 Jan.
Artigo em Japonês | MEDLINE | ID: mdl-20104010

RESUMO

A 82-year-old man was referred to our hospital for treatment of hormone-refractory prostate cancer with liver metastases. The obstruction of intrahepatic bile ducts due to the rapid growth of liver metastases induced liver dysfunction. We administered 25 mg/m(2) docetaxel on day1 and 280 mg/body estramustine phosphate on day 1 to day 3, every 4 weeks. After two courses of this combined chemothrapy, the liver metastases were markedly reduced in size with the rapid improvement of liver function.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/secundário , Neoplasias da Próstata/tratamento farmacológico , Idoso de 80 Anos ou mais , Antineoplásicos/administração & dosagem , Antineoplásicos Alquilantes/administração & dosagem , Docetaxel , Estramustina/administração & dosagem , Humanos , Hepatopatias/tratamento farmacológico , Hepatopatias/etiologia , Neoplasias Hepáticas/complicações , Masculino , Neoplasias da Próstata/patologia , Taxoides/administração & dosagem
17.
Hinyokika Kiyo ; 55(8): 495-8, 2009 Aug.
Artigo em Japonês | MEDLINE | ID: mdl-19764536

RESUMO

Mixed epithelial and stromal tumor of kidney (MEST-K) is a rare benign renal tumor that was first described by Michal and Syrucek in 1998. Its frequency is 0.2-0.28% of all the renal tumors. Here, we report an additional case of MEST-K occurring in a 28-year-old woman. The patient visited a hospital with complaints of lumbago and fever caused by pyelonephritis. The computed tomography revealed hydronephrosis and a cystic tumor in the right kidney, and laparoscopic right nephrectomy was performed. The resected kidney contained a cystic lesion with a grayish-white mural nodule, in the lower portion. The entire lesion measured 5 cm in diameter, and the mural nodule 2.5 cm in diameter. Histologically, the cyst was lined with tall columnar and transitional epithelia. The mural nodule showed microcystic architectures lined with tall columnar and transitional epithelia, scattered in a compact stroma. Immunohistochemically, spindle cells in the stroma were positive for smooth muscle-specific actin, and estrogen and progesterone receptors (ER and PR). Based on these findings, the tumor was diagnosed as MEST-K. MEST-K was newly introduced to the WHO classification of renal tumors, with a pathogenesis related to long-term estrogen exposure, because of ER and PR expression in the stroma. It is important to consider the possibility of this tumor when encountering cases of cystic tumor in middle-aged and older women, and men with a previous history of estrogen administration.


Assuntos
Neoplasias Renais/patologia , Neoplasias Complexas Mistas/patologia , Adulto , Feminino , Humanos
18.
Hinyokika Kiyo ; 55(7): 437-9, 2009 Jul.
Artigo em Japonês | MEDLINE | ID: mdl-19673435

RESUMO

A 28-year-old man with adult-onset idiopathic male hypogonadotropic hypogonadism (MHH) is reported. He had been delivered normally and had normal puberty. He was referred to our hospital with a chief complaint of infertility. Serum levels of testosterone, luteinizing hormone, and follicle stimulating hormone (FSH) were low. Semen analysis demonstrated azoospermia. Pituitary hypofunction was suggested by gonadotropin releasing hormone (GnRH) loading test. Magnetic resonance images did not detect any abnormalities in the hypothalamic-pituitary region. After a diagnosis of adult-onset hypogonadotropic hypogonadism was established, the patient received human chorionic gonadotropin (hCG) and recombinant FSH treatment. After 5 months, his sperm count reached 6.9 x 10(6) per ml and his wife became pregnant. Adult-onset HH in most cases is caused by tumors and trauma. To our knowledge 17 cases of adult-onset idiopathic HH have been reported, and there were only 3 cases that were caused by pituitary dysfunction. This report showed that r-FSH and hCG therapy was effective in promoting fertility in a patient with adult-onset idiopathic MHH.


Assuntos
Hipogonadismo/complicações , Infertilidade Masculina/etiologia , Adulto , Gonadotropina Coriônica/administração & dosagem , Feminino , Hormônio Foliculoestimulante/administração & dosagem , Humanos , Hipogonadismo/diagnóstico , Hipogonadismo/tratamento farmacológico , Masculino , Gravidez
19.
Phys Rev Lett ; 103(20): 203601, 2009 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-20365982

RESUMO

We present a feedback scheme to produce quantum non-Gaussian states from linear optical elements. Instead of traditional additive control methods, we introduce a mutiplicative feedback control and apply it to the deterministic generation of quantum superposition states. The protocol of feedback control is based on quantum nondemolition measurement of a quadrature, multifeedback structure, and Lyapunov stability for feedback design.

20.
J Cell Biol ; 183(5): 893-908, 2008 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-19047464

RESUMO

Localization of presynaptic components to synaptic sites is critical for hippocampal synapse formation. Cell adhesion-regulated signaling is important for synaptic development and function, but little is known about differentiation of the presynaptic compartment. In this study, we describe a pathway that promotes presynaptic development involving p120catenin (p120ctn), the cytoplasmic tyrosine kinase Fer, the protein phosphatase SHP-2, and beta-catenin. Presynaptic Fer depletion prevents localization of active zone constituents and synaptic vesicles and inhibits excitatory synapse formation and synaptic transmission. Depletion of p120ctn or SHP-2 similarly disrupts synaptic vesicle localization with active SHP-2, restoring synapse formation in the absence of Fer. Fer or SHP-2 depletion results in elevated tyrosine phosphorylation of beta-catenin. beta-Catenin overexpression restores normal synaptic vesicle localization in the absence of Fer or SHP-2. Our results indicate that a presynaptic signaling pathway through p120ctn, Fer, SHP-2, and beta-catenin promotes excitatory synapse development and function.


Assuntos
Moléculas de Adesão Celular/metabolismo , Hipocampo/enzimologia , Neurônios/enzimologia , Fosfoproteínas/metabolismo , Terminações Pré-Sinápticas/enzimologia , Proteína Tirosina Fosfatase não Receptora Tipo 11/metabolismo , Proteínas Tirosina Quinases/metabolismo , Transmissão Sináptica , beta Catenina/metabolismo , Animais , Axônios/enzimologia , Cateninas , Moléculas de Adesão Celular/genética , Células Cultivadas , Citoplasma/enzimologia , Potenciais Pós-Sinápticos Excitadores , Hipocampo/embriologia , Fosfoproteínas/genética , Fosforilação , Proteína Tirosina Fosfatase não Receptora Tipo 11/genética , Proteínas Tirosina Quinases/genética , Interferência de RNA , RNA Interferente Pequeno , Ratos , Ratos Sprague-Dawley , Fatores de Tempo , Transfecção , beta Catenina/genética , Proteína rhoA de Ligação ao GTP/metabolismo , delta Catenina
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