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1.
Am J Occup Ther ; 78(5)2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39054681

RESUMO

IMPORTANCE: Self-feeding independence is often the first goal in acute stroke rehabilitation. Attention deficits appear frequently after stroke, but neuropsychological tests may be difficult to perform in the acute phase, and the effect on self-feeding activities may be difficult to detect. Therefore, we aimed to clarify behavioral problems with self-feeding using the Moss Attention Rating Scale (MARS), a behavioral observational rating scale of attentional function, for a better understanding of the effects of self-feeding. OBJECTIVE: To identify behavioral problems caused by attention deficits among patients with acute stroke who need assistance in self-feeding, using the MARS. DESIGN: Cross-sectional single-center study. SETTING: St. Marianna University Yokohama Seibu Hospital, Kanagawa, Japan. PARTICIPANTS: A total of 96 patients (42 women and 54 men) were admitted to the hospital for stroke treatment. Patients' median age was 75.0 yr. The date of evaluation was a median of 3.0 days from admission. OUTCOME AND MEASURES: The primary outcome was the FIM® eating subscore. The secondary outcome was the MARS score. RESULTS: Significant differences were noted in the total raw MARS, logit, and three-factor scores for self-feeding independence (p < .01). The effect size of the consistent or sustained factor on independence was large (r = .83). CONCLUSIONS AND RELEVANCE: Behavioral problems related to self-feeding dependence include the inability for sustained attention. Our results suggest that sustained concentration during self-feeding is necessary for eating independence. Rehabilitation focused on sustained attention is important for independent self-feeding. Plain-Language Summary: A patient's self-feeding independence is often the first goal in acute stroke rehabilitation. Patients frequently experience attention deficits after a stroke, but neuropsychological tests may be difficult to perform in the acute phase of rehabilitation, and the effect of attention deficits on self-feeding may be difficult to identify. To have a better understanding of the effects on self-feeding, this study aimed to identify behavioral problems using the Moss Attention Rating Scale (MARS). The study found that the MARS can be used to identify behavioral problems related to self-feeding independence, which can help occupational therapists to develop rehabilitation programs for their clients who have experienced a stroke.


Assuntos
Reabilitação do Acidente Vascular Cerebral , Humanos , Masculino , Feminino , Idoso , Estudos Transversais , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Acidente Vascular Cerebral/complicações , Atenção , Comportamento Problema , Comportamento Alimentar , Japão
2.
Heart Vessels ; 34(4): 724-734, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30460575

RESUMO

Pulmonary arterial hypertension (PAH) is a progressive disease associated with vasoconstriction and remodeling. Intracellular Ca2+ signaling regulates the contraction of pulmonary arteries and the proliferation of pulmonary arterial smooth muscle cells (PASMCs); however, it is not clear which molecules related to Ca2+ signaling contribute to the progression of PAH. In this study, we found the specific expression of type 2 inositol 1,4,5-trisphosphate receptor (IP3R2), which is an intracellular Ca2+ release channel, on the sarco/endoplasmic reticulum in mouse PASMCs, and demonstrated its inhibitory role in the progression of PAH using a chronic hypoxia-induced PAH mouse model. After chronic hypoxia exposure, IP3R2-/- mice exhibited the significant aggravation of PAH, as determined by echocardiography and right ventricular hypertrophy, with significantly greater medial wall thickness by immunohistochemistry than that of wild-type mice. In IP3R2-/- murine PASMCs with chronic hypoxia, a TUNEL assay revealed the significant suppression of apoptosis, whereas there was no significant change in proliferation. Thapsigargin-induced store-operated Ca2+ entry (SOCE) was significantly enhanced in IP3R2-/- PASMCs in both normoxia and hypoxia based on in vitro fluorescent Ca2+ imaging. Furthermore, the enhancement of SOCE in IP3R2-/- PASMCs was remarkably suppressed by the addition of DPB162-AE, an inhibitor of the stromal-interacting molecule (STIM)-Orai complex which is about 100 times more potent than 2-APB. Our results indicate that IP3R2 may inhibit the progression of PAH by promoting apoptosis and inhibiting SOCE via the STIM-Orai pathway in PASMCs. These findings suggest a previously undetermined role of IP3R in the development of PAH and may contribute to the development of targeted therapies.


Assuntos
Apoptose , Cálcio/metabolismo , Hipertensão Pulmonar/fisiopatologia , Receptores de Inositol 1,4,5-Trifosfato/metabolismo , Músculo Liso Vascular/metabolismo , Artéria Pulmonar/fisiopatologia , Animais , Sinalização do Cálcio , Células Cultivadas , Modelos Animais de Doenças , Progressão da Doença , Hipertensão Pulmonar/metabolismo , Hipertensão Pulmonar/patologia , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Músculo Liso Vascular/patologia , Artéria Pulmonar/patologia , Vasoconstrição
3.
J Minim Invasive Surg ; 24(3): 152-157, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35600100

RESUMO

Purpose: Single-port laparoscopic surgery is anticipated to become the future of minimally invasive surgery. We have devised an alternative approach for laparoscopic cholecystectomy by inserting a single port at the umbilicus and using the abdominal wall-lifting method, without establishing pneumoperitoneum. Methods: Retrospective analysis of 130 patients undergoing laparoscopic cholecystectomy was done to compare the conventional laparoscopic cholecystectomy (CLC) (n = 69) and the novel single-port laparoscopic cholecystectomy (SLC) using the abdominal wall-lifting method (n = 61). The surgical procedures were as follows. A 2- to 3-cm transumbilical incision was made, and a wound retractor was inserted into the abdomen without difficulty. Abdominal distension was obtained using a fan-shaped retractor without the use of carbon dioxide insufflations. A 5-mm flexible scope and modified curved graspers and dissectors were used to give the feeling of triangulation during dissection. Results: The SLC group consisted of 25 males and 36 females with a mean age of 58.1 ± 7.2 years and a mean body mass index of 23.1 ± 3.2 kg/m2. The two groups were comparable for mean age, sex, disease, American Society of Anesthesiologists physical status classification, and comorbidity. Likewise, the duration of operation, postoperative hospital stays, complications, the number of use of analgesics, and conversion rate to open technique were not significantly different in the two groups. Conclusion: The impaired view in single-port laparoscopic surgery can be improved by using articulating instruments that can be rotated out of the field of view. This novel gasless method is cost-effective and produces minimal postoperative discomfort with no additional scars.

4.
World J Surg Oncol ; 7: 7, 2009 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-19138398

RESUMO

BACKGROUND: Th1/Th2 cell balance is thought to be shifted toward a Th2-type immune response not only by malignancy but also by surgical stress. The aim of this study was to estimate perioperative immune responses with respect to the Th1/Th2 balance in patients with gastrointestinal cancer. METHODS: Ninety-four patients who underwent abdominal surgeries were divided into three groups: gastric resection (n = 40), colorectal resection (n = 34) and hepatic resection (n = 20). Twelve patients undergoing laparoscopic cholecystectomy and 20 healthy subjects were served as control groups. Intracellular cytokine staining in CD4+ T lymphocytes was identified to characterize Th1/Th2 balance. Th1/Th2 balance was evaluated before operation and until postoperative days (POD) 14. RESULTS: The preoperative Th1/Th2 ratio was significantly lower in patients with malignancy compared with control. The Th1/Th2 ratio of patients in all groups decreased significantly postoperatively. Th1/Th2 balance on POD 2 in patients with malignancy was significantly decreased compared to patients with laparoscopic cholecystectomy, but there were no significant differences among the four groups on POD 14. CONCLUSION: Patients with malignancy showed an abnormal perioperative Th1/Th2 balance suggesting predominance of a type-2 immune response. Major abdominal surgeries induce a marked shift in Th1/Th2 balance toward Th2 in the early postoperative stage.


Assuntos
Neoplasias Colorretais/imunologia , Procedimentos Cirúrgicos do Sistema Digestório/efeitos adversos , Neoplasias Gástricas/imunologia , Estresse Fisiológico , Idoso , Contagem de Linfócito CD4 , Linfócitos T CD4-Positivos/imunologia , Estudos de Casos e Controles , Colecistectomia Laparoscópica/efeitos adversos , Neoplasias Colorretais/fisiopatologia , Neoplasias Colorretais/cirurgia , Feminino , Humanos , Interferon gama/imunologia , Interleucina-4/imunologia , Fígado/cirurgia , Masculino , Pessoa de Meia-Idade , Assistência Perioperatória , Neoplasias Gástricas/fisiopatologia , Neoplasias Gástricas/cirurgia , Células Th1/imunologia , Células Th2/imunologia
5.
BMC Cancer ; 8: 188, 2008 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-18597678

RESUMO

BACKGROUND: A number of studies have investigated whether the activity levels of enzymes involved in 5-fluorouracil (5-FU) metabolism are prognostic factors for survival in patients with colorectal carcinoma. Most reports have examined thymidylate synthetase (TS) and dihydropyrimidine dehydrogenase (DPD) in unresectable or metastatic cases, therefore it is unclear whether the activity of these enzymes is of prognostic value in colorectal cancer patients treated with radical resection and adjuvant chemotherapy with 5-FU. METHODS: This study examined fresh frozen specimens of colorectal carcinoma from 40 patients who had undergone curative operation and were orally administered adjuvant tegafur/uracil (UFT) chemotherapy. TS, DPD and orotate phosphoribosyl transferase (OPRT) activities were assayed in cancer tissue and adjacent normal tissue and their association with clinicopathological variables was investigated. In addition, the relationships between TS, DPD and OPRT activities and patient survival were examined to determine whether any of these enzymes could be useful prognostic factors. RESULTS: While there was no clear relationship between pathological findings and TS or DPD activity, OPRT activity was significantly lower in tumors with lymph node metastasis than in tumors lacking lymph node metastasis. Postoperative survival was significantly better in the groups with low TS activity and/or high OPRT activity. CONCLUSION: TS and OPRT activity levels in tumor tissue may be important prognostic factors for survival in Dukes' B and C colorectal carcinoma with radical resection and adjuvant chemotherapy with UFT.


Assuntos
Neoplasias Colorretais/enzimologia , Di-Hidrouracila Desidrogenase (NADP)/metabolismo , Fluoruracila/uso terapêutico , Neoplasias Epiteliais e Glandulares/enzimologia , Orotato Fosforribosiltransferase/metabolismo , Timidilato Sintase/metabolismo , Idoso , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/cirurgia , Tratamento Farmacológico , Ativação Enzimática/efeitos dos fármacos , Feminino , Fluoruracila/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Epiteliais e Glandulares/diagnóstico , Neoplasias Epiteliais e Glandulares/mortalidade , Neoplasias Epiteliais e Glandulares/cirurgia , Prognóstico , Análise de Sobrevida
6.
Sci Rep ; 8(1): 17954, 2018 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-30560905

RESUMO

We performed multi-b and multi-diffusion-time diffusion-weighted magnetic resonance imaging on aquaporin-4-expressing (AQ) and -non-expressing (noAQ) cells, and demonstrated a clear difference between the signals from the two cell types. The data were interpreted using a two-compartment (intra and extracellular spaces) model including inter-compartmental exchange. It was also assumed that restricted diffusion of water molecules inside the cells leads to the intracellular diffusion coefficient being inversely proportional to the diffusion-time. Estimates of the water-exchange-times obtained with this model are compared to those measured using an independent optical imaging technique (coherent anti-Stokes Raman scattering imaging, CARS). For both techniques it was found that the exchange-time estimated for the noAQ cells was significantly longer than that for the AQ cells.


Assuntos
Aquaporina 4/metabolismo , Imagem de Difusão por Ressonância Magnética , Imagem Molecular , Análise Espectral Raman , Água/metabolismo , Aquaporina 4/genética , Imagem de Difusão por Ressonância Magnética/métodos , Espaço Extracelular/metabolismo , Espaço Intracelular/metabolismo , Modelos Teóricos , Imagem Molecular/métodos , Análise Espectral Raman/métodos
7.
Biochem J ; 395(1): 65-71, 2006 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-16390331

RESUMO

Invasive tumour cells, such as gliomas, frequently express EGF (epidermal growth factor) receptor at a high level and they exhibit enhanced cell migration in response to EGF. We reported previously that tumour cell migration is associated with ectodomain cleavage of CD44, the major adhesion molecule that is implicated in tumour invasion and metastasis, and that the cleavage is enhanced by ligation of CD44. In the present study, we show that EGF promotes CD44 cleavage and CD44-dependent cell migration. Introduction of a dominant-negative mutant of the small GTPase Rac1 or depletion of Rac1 by RNAi (RNA interference) abrogated CD44 cleavage induced by EGF. Treatment with PD98059, an inhibitor for MEK (mitogen-activated protein kinase/extracellular-signal-regulated kinase kinase), also suppressed the CD44 cleavage. Furthermore, RNAi studies showed that EGF induced ADAM10 (a disintegrin and metalloproteinase 10)-dependent CD44 cleavage and cell migration. These results indicate that EGF induces ADAM10-mediated CD44 cleavage through Rac1 and mitogen-activated protein kinase activation, and thereby promotes tumour cell migration and invasion.


Assuntos
Proteínas ADAM/metabolismo , Desintegrinas/metabolismo , Fator de Crescimento Epidérmico/farmacologia , Receptores de Hialuronatos/metabolismo , Proteínas de Membrana/metabolismo , Proteínas rac1 de Ligação ao GTP/metabolismo , Proteína ADAM10 , Secretases da Proteína Precursora do Amiloide , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Extensões da Superfície Celular/efeitos dos fármacos , Extensões da Superfície Celular/metabolismo , Ativação Enzimática/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Humanos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Pseudópodes/efeitos dos fármacos , Pseudópodes/metabolismo , Células Tumorais Cultivadas
8.
Biochem Biophys Rep ; 7: 77-83, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28955892

RESUMO

Neuromyelitis optica (NMO), an autoimmune disease of the central nervous system, is characterized by an autoantibody called NMO-IgG that recognizes the extracellular domains (ECDs) of aquaporin-4 (AQP4). In this study, monoclonal antibodies (mAbs) against the ECDs of mouse AQP4 were established by a baculovirus display method. Two types of mAb were obtained: one (E5415A) recognized both M1 and M23 isoforms, and the other (E5415B) almost exclusively recognized the square-array-formable M23 isoform. While E5415A enhanced endocytosis of both M1 and M23, followed by degradation in cells expressing AQP4, including astrocytes, E5415B did so to a much lesser degree, as determined by live imaging using fluorescence-labeled antibodies and by Western blotting of lysate of cells treated with these mAbs. E5415A promoted cluster formation of AQP4 on the cell surface prior to endocytosis as determined by immunofluorescent microscopic observation of bound mAbs to astrocytes as well as by Blue native PAGE analysis of AQP4 in the cells treated with the mAbs. These observations clearly indicate that an anti-AQP4-ECDs antibody possessing an ability to form a large cluster of AQP4 by cross-linking two or more tetramers outside the AQP4 arrays enhances endocytosis and the subsequent lysosomal degradation of AQP4.

9.
FEBS Lett ; 589(5): 608-14, 2015 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-25643985

RESUMO

Aquaporin-7 (AQP7) is expressed in adipose tissue, permeated by water and glycerol, and is involved in lipid metabolism. AQP7-null mice develop obesity, insulin resistance, and adipocyte hypertrophy. Here, we show that AQP7 is expressed in adipocyte plasma membranes, and is re-localized to intracellular membranes in response to catecholamine in mouse white adipose tissue. We found that internalization of AQP7 was induced by PKA activation and comparative gene identification 58 (CGI-58). This relocation was confirmed by functional studies in 3T3-L1 adipocytes. Collectively, these results suggest that AQP7 makes several contributions to adipocyte metabolism, in both cortical and intracellular membranes.


Assuntos
Adipócitos Brancos/metabolismo , Aquaporinas/metabolismo , 1-Acilglicerol-3-Fosfato O-Aciltransferase/genética , 1-Acilglicerol-3-Fosfato O-Aciltransferase/metabolismo , Células 3T3-L1 , Animais , Proteínas Quinases Dependentes de AMP Cíclico/genética , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Imuno-Histoquímica , Camundongos , Transporte Proteico
10.
J Med Invest ; 50(1-2): 108-11, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12630575

RESUMO

A 70-year-old woman was admitted to our hospital with a complaint of bulging in the right lower portion of the abdomen. The bulging was in accordance with an old operative scar for appendicitis. The findings of computed tomography (CT) showed defects in the abdominal muscles and the protrusion of the intestine into the subcutaneous fat. The patient was diagnosed with incisional hernia after appendectomy and underwent a repair of the incisional hernia, using the prolene hernia system double-layer mesh. The patient's post-operative course was excellent. Recently, the prolene hernia system, double-layer mesh was reported to be effective for groin hernias due to its advantageous protection the recurrence through reinforcement of the patient's myopectrial orifice. It is suggested that this new device is also useful for small incisional hernias.


Assuntos
Hérnia Ventral/cirurgia , Próteses e Implantes , Telas Cirúrgicas , Idoso , Apendicectomia , Cicatriz/complicações , Feminino , Hérnia Ventral/diagnóstico por imagem , Hérnia Ventral/etiologia , Humanos , Polipropilenos , Complicações Pós-Operatórias/cirurgia , Sucção , Técnicas de Sutura , Tomografia Computadorizada por Raios X
11.
J Med Invest ; 49(3-4): 186-92, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12323009

RESUMO

An 85-year-old woman was admitted to our hospital because of vomiting. An upper gastrointestinal series what showed a large esophageal hiatus hernia, suggesting an association with extrinsic pressure in the middle portion of the stomach. An upper gastrointestinal endoscopic examination showed severe esophagitis and a prominent narrowing in the middle portion of the stomach, however, it showed normal gastric mucosa findings. CT and MRI revealed a large tumor extending from the region of the lower chest to the upper abdomen. From these findings, the tumor was diagnosed as gastrointestinal stromal tumor (GIST), which arose from the gastric wall and complicated with an esophageal hiatus hernia. We performed a laparotomy, however, the tumor showed severe invasion to the circumferential organs. Therefore, we abandoned the excision of the tumor. Histologically, the tumor was composed of spindle shaped cells with marked nuclear atypia and prominent mitosis. The tumor cells were strongly positive for CD34 and c-kit by immunohistochemical examination. From these findings, the tumor was definitely diagnosed as a malignant GIST. As palliative treatment, we implanted a self-expandable metallic stent in the narrow segment of the stomach. The patient could eat solid food and was discharged. In the treatment of esophageal hiatus hernia, the rare association of GIST should be considered.


Assuntos
Hérnia Hiatal/complicações , Neoplasias de Tecido Conjuntivo/complicações , Neoplasias Gástricas/complicações , Idoso , Idoso de 80 Anos ou mais , Progressão da Doença , Esofagite/complicações , Evolução Fatal , Feminino , Humanos , Laparotomia , Imageamento por Ressonância Magnética , Invasividade Neoplásica , Neoplasias de Tecido Conjuntivo/diagnóstico , Neoplasias de Tecido Conjuntivo/patologia , Neoplasias de Tecido Conjuntivo/cirurgia , Cuidados Paliativos , Complicações Pós-Operatórias , Stents , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/patologia , Neoplasias Gástricas/cirurgia , Tomografia Computadorizada por Raios X , Ultrassonografia de Intervenção
12.
Hepatol Res ; 24(3): 316, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12393034

RESUMO

We report a rare case of adenomatous hyperplasia (AH) with malignant transformation, which was observed initially in the liver with chronic hepatitis C. A 47-year-old man was admitted to the hospital and chronic active hepatitis was diagnosed using fine needle biopsy, in addition abdominal computed tomography (CT) and ultrasonography showed multiple and hypovascular liver mass. Needle biopsy of the nodules showed AH. Despite transcatheter arterial embolization and percutaneous ethanol injection therapy (PEIT), the patient was readmitted due to enlargement of the nodules and elevation of alpha-fetoprotein 9 months later. On readmission, the nodules in the liver showed early-stage well-differentiated hepatocellular carcinoma (HCC) histopathologically, that were strongly stained on CT-arteriography and were stained less than the surrounding liver on CT-arterial portography, indicating arterial supply in the nodules and malignant transformation. Thereafter, the patient developed jaundice, and enhanced CT and magnetic resonance imaging showed multiple nodules, which occupied most of the liver, and needle biopsy revealed typical well-differentiated HCC. The patient died of hepatic failure 3 years after the initial admission. In this case, it was confirmed that AH transformed into HCC, which showed a multiple tumor on pathological diagnosis. It has been reported that borderline lesions are curable by less aggressive procedures such as enucleation and PEIT. However, such procedures may not be useful for this type of HCC, which rapidly developed from borderline lesions of the liver.

13.
PLoS One ; 9(2): e87644, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24558371

RESUMO

Freezing is usually used for preservation and storage of biological samples; however, this process may have some adverse effects such as cell membrane damage. Aquaporin (AQP), a water channel protein, has been suggested to play some roles for cryopreservation although its molecular mechanism remains unclear. Here we show that membrane damage caused by ultra-quick freezing is rescued by the expression of AQP4. We next examine if the expression of AQP combined with ultra-quick freezing can be used to select cells efficiently under freezing conditions where most cells are died. CHO cells stably expressing AQP4 were exclusively selected from mixed cell cultures. Having identified the increased expression of AQP4 during ES cell differentiation into neuro-ectoderm using bioinformatics, we confirmed the improved survival of differentiated ES cells with AQP4 expression. Finally we show that CHO cells transiently transfected with Endothelin receptor A and Aqp4 were also selected and concentrated by multiple cycles of freezing/thawing, which was confirmed with calcium imaging in response to endothelin. Furthermore, we found that the expression of AQP enables a reduction in the amount of cryoprotectants for freezing, thereby decreasing osmotic stress and cellular toxicity. Taken together, we propose that this simple but efficient and safe method may be applicable to the selection of mammalian cells for applications in regenerative medicine as well as cell-based functional assays or drug screening protocols.


Assuntos
Aquaporina 4/metabolismo , Criopreservação/métodos , Animais , Aquaporina 1/metabolismo , Células CHO , Membrana Celular/metabolismo , Permeabilidade da Membrana Celular/genética , Sobrevivência Celular , Células Cultivadas , Cricetinae , Cricetulus , Cães , Células-Tronco Embrionárias/citologia , Congelamento , Humanos , Células Madin Darby de Rim Canino , Camundongos , Camundongos Transgênicos , Placa Neural/metabolismo , Osmose , Plasmídeos/metabolismo , Receptor de Endotelina A/metabolismo
14.
Sci Rep ; 3: 2745, 2013 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-24067894

RESUMO

To date, it has not been possible to measure microscopic diffusive water movements in epithelia and in the interstitial space of complex tissues and organs. Diffusive water movements are essential for life because they convey physiologically important small molecules, e.g. nutrients and signaling ligands throughout the extracellular space of complex tissues. Here we report the development of a novel method for the direct observation and quantitative analysis of water diffusion dynamics in a biologically organized tissue using Coherent Anti-Stokes Raman Scattering (CARS) microscopy. Using a computer simulation model to analyze the CARS O-H bond vibration data during H2O/D2O exchange in a 3D epithelial cyst, we succeeded in measuring the diffusive water permeability of the individual luminal and basolateral water pathways and also their response to hormonal stimulation. Our technique will be applicable to the measurement of diffusive water movements in other structurally complex and medically important tissues and organs.


Assuntos
Epitélio/metabolismo , Microscopia/métodos , Análise Espectral Raman , Água/metabolismo , Animais , Aquaporina 4/metabolismo , Permeabilidade da Membrana Celular , Medição da Troca de Deutério , Difusão , Cães , Células Epiteliais/metabolismo , Epitélio/efeitos dos fármacos , Células Madin Darby de Rim Canino , Camundongos , Modelos Biológicos , Reprodutibilidade dos Testes , Processamento de Sinais Assistido por Computador , Transfecção , Vasopressinas/farmacologia
15.
J Mol Biol ; 407(2): 222-31, 2011 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-21277858

RESUMO

To examine the in vivo functions of protein kinase N (PKN), one of the effectors of Rho small guanosine triphosphatases (GTPases), we used the nematode Caenorhabditis elegans as a genetic model system. We identified a C. elegans homologue (pkn-1) of mammalian PKN and confirmed direct binding to C. elegans Rho small GTPases. Using a green fluorescent protein reporter, we showed that pkn-1 is mainly expressed in various muscles and is localized at dense bodies and M lines. Overexpression of the PKN-1 kinase domain and loss-of-function mutations by genomic deletion of pkn-1 resulted in a loopy Unc phenotype, which has been reported in many mutants of neuronal genes. The results of mosaic analysis and body wall muscle-specific expression of the PKN-1 kinase domain suggests that this loopy phenotype is due to the expression of PKN-1 in body wall muscle. The genomic deletion of pkn-1 also showed a defect in force transmission. These results suggest that PKN-1 functions as a regulator of muscle contraction-relaxation and as a component of the force transmission mechanism.


Assuntos
Caenorhabditis elegans/metabolismo , Contração Muscular/genética , Proteína Quinase C/metabolismo , Animais , Animais Geneticamente Modificados , Caenorhabditis elegans/genética , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Mamíferos/genética , Mamíferos/metabolismo , Modelos Genéticos , Músculos/metabolismo , Mutação , Neurônios/metabolismo , Fenótipo , Ligação Proteica/genética , Proteína Quinase C/genética
16.
Biophysics (Nagoya-shi) ; 3: 63-73, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-27857568

RESUMO

RhoA and Rac1 are small GTPases primarily involved in cytoskeletal remodeling. Many biochemical studies have suggested that they are also key organizers of cell-substrate adhesion. Recently, fluorescence resonance energy transfer (FRET)-based indicators have been developed to visualize RhoA and Rac1 activity in living cells [Yoshizaki et al., J. Cell Biol. 162, 223 (2003); Pertz et al., Nature 440, 1069 (2006)]. These indicators use one of the interactions between RhoA (Rac1) and the RhoA (Rac1)-binding domain of their effector proteins. However, distribution of RhoA activity in single cells has not yet been observed with micrometer-scale resolution. Here, we employed an approach that detects GDP/GTP exchange on small GTPases by using FRET from YFP-fused small GTPases to a fluorescent analogue of GTP, BODIPY(TR)-GTP. This approach allowed us to visualize confined localization of active (GTP-bound forms of) RhoA and Rac1 in individual focal adhesions. Activated RhoA accumulated in immobile and long-lived focal adhesions but was not evident in unstable and temporary adhesions, while activated Rac1 was observed at every adhesion. Our results suggest that RhoA is the major regulator determining the stability of individual cell adhesion structures.

17.
J Biol Chem ; 279(6): 4541-50, 2004 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-14623895

RESUMO

CD44 is a major cell surface adhesion molecule for hyaluronan, a component of the extracellular matrix, and is implicated in tumor metastasis and invasion. We reported previously that hyaluronan oligosaccharides induce CD44 cleavage from tumor cells. Here we show that engagement of CD44 promotes CD44 cleavage and tumor cell migration, both of which were suppressed by a metalloproteinase inhibitor KB-R7785 and tissue inhibitor of metalloproteinases-1 (TIMP-1) but not by TIMP-2. We also present evidence that blockade of metalloproteinase-disintegrin ADAM10 (a disintegrin and metalloproteinase 10) by RNA interference suppresses CD44 cleavage induced by its ligation. Engagement of CD44 concurrently induced activation of the small GTPase Rac1 and led to drastic changes in cell morphology and actin cytoskeleton with redistribution of CD44 to newly generated membrane ruffling areas. A fluorescence resonance energy transfer approach to visualize GTP-bound Rac1 in living cells revealed the localization of the active Rac1 in the leading edge of the membrane ruffling areas upon ligation of CD44. Taken together, our results indicate that the cleavage of CD44 catalyzed by ADAM10 is augmented by the intracellular signaling elicited by engagement of CD44, through Rac-mediated cytoskeletal rearrangement, and suggest that CD44 cleavage contributes to the migration and invasion of tumor cells.


Assuntos
Movimento Celular/fisiologia , Glioblastoma/imunologia , Glioblastoma/fisiopatologia , Receptores de Hialuronatos/metabolismo , Proteínas rac1 de Ligação ao GTP/metabolismo , Proteínas ADAM , Proteína ADAM10 , Secretases da Proteína Precursora do Amiloide , Anticorpos Monoclonais/farmacologia , Sequência de Bases , Linhagem Celular Tumoral , Movimento Celular/imunologia , DNA Complementar/genética , Ativação Enzimática , Glioblastoma/patologia , Humanos , Proteínas de Membrana/antagonistas & inibidores , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Metaloendopeptidases/antagonistas & inibidores , Metaloendopeptidases/genética , Metaloendopeptidases/metabolismo , Invasividade Neoplásica/imunologia , Invasividade Neoplásica/fisiopatologia , Interferência de RNA , RNA Interferente Pequeno/genética , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Transdução de Sinais , Inibidor Tecidual de Metaloproteinase-1/farmacologia , Inibidor Tecidual de Metaloproteinase-2/farmacologia , Proteínas rac1 de Ligação ao GTP/genética
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