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1.
Int. braz. j. urol ; 45(3): 541-548, May-June 2019. tab, graf
Artigo em Inglês | LILACS-Express | ID: biblio-1012322

RESUMO

ABSTRACT Objectives: To investigate whether Glasgow Prognostic Score has prognostic significance in patients with upper urinary urothelial carcinoma. Patients and methods: We retrospectively reviewed the clinical records of 74 patients with upper urinary urothelial carcinoma. We set the cut-off value for C-reactive protein as 1.0mg/dL, and 3.5mg/dL for albumin as Glasgow Prognostic Score. Their blood data including albumin and C-reactive protein for Glasgow Prognostic Score and cytokeratin 19 fragment 21-1 as a tumor marker were measured before starting treatment. The patients were stratified into three groups with Glasgow Prognostic Score: The Group-1, albumin ≥3.5g/dL and C-reactive protein < 1.0mg/dL; Group-2, albumin < 3.5g/dL or C-reactive protein ≥1.0mg/dL; Group-3, albumin < 3.5g/dL and C-reactive protein ≥1.0mg/dL. Results: The median follow-up for all patients was 26.9 months (range: 10.9-91.1 months), during which 37 (50%) patients died. There was a significant difference in the estimated survival rate among the 3 groups stratified by Glasgow Prognostic Score. The estimated survival rate in the Group-1 was significantly higher than those in Groups 2 and 3. In the univariate analysis C-reactive protein, serum cytokeratin 19 fragment 21-1 and Glasgow Prognostic Score were significant predictors of overall survival. On the multivariate analysis, serum cytokeratin 19 fragment 21-1 and Glasgow Prognostic Score were independently associated with shorter overall survival. Conclusion: Our review suggests Glasgow Prognostic Score may play as a prognostic predictor for upper urinary urothelial carcinoma.

2.
Artigo em Inglês | MEDLINE | ID: mdl-31077793

RESUMO

BACKGROUND: Proteins change their conformation depending on function. Although a vast number of static pictures of proteins have been accumulated, information regarding their dynamics in function is limited. Diffracted X-ray tracking (DXT) is a good candidate to obtain the missing data. SCOPE OF REVIEW: A gold nanocrystal was attached to the target protein as a probe and the motion of the X-ray diffraction spots from the crystal corresponded to the motion of the target. Although it has advantages of high temporal (sub-millisecond) and spatial (approximately 0.1°) resolutions, it is not extensively utilized. This review focused on its effective application from a user's perspective. We also present an example with the KcsA channel and the status of recent developments to show the future possibilities of the method. MAJOR CONCLUSIONS: DXT is a powerful method to investigate intramolecular structural changes. For instance, in the KcsA channel, the method revealed a wave of conformational changes transmitted from the gate region to the end of the molecule. The method is continuously being developed, and users can choose an appropriate measurement system depending on the condition of their sample. GENERAL SIGNIFICANCE: Revealing the protein structural changes with respect to function is an important frontier. The most distinctive feature of the DXT method is that both high temporal and spatial resolutions are achievable, and it is possible to track the motions of multiple molecules at the same time. This feature is an advantage for screening molecules associated with the target proteins (e.g., ligands and medicines).

3.
Int Braz J Urol ; 45(3): 541-548, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31038863

RESUMO

OBJECTIVES: To investigate whether Glasgow Prognostic Score has prognostic significance in patients with upper urinary urothelial carcinoma. PATIENTS AND METHODS: We retrospectively reviewed the clinical records of 74 patients with upper urinary urothelial carcinoma. We set the cut-off value for C-reactive protein as 1.0mg/dL, and 3.5mg/dL for albumin as Glasgow Prognostic Score. Their blood data including albumin and C-reactive protein for Glasgow Prognostic Score and cytokeratin 19 fragment 21-1 as a tumor marker were measured before starting treatment. The patients were stratified into three groups with Glasgow Prognostic Score: The Group-1, albumin ≥3.5g/dL and C-reactive protein < 1.0mg/dL; Group-2, albumin < 3.5g/dL or C-reactive protein ≥1.0mg/dL; Group-3, albumin < 3.5g/dL and C-reactive protein ≥1.0mg/dL. RESULTS: The median follow-up for all patients was 26.9 months (range: 10.9-91.1 months), during which 37 (50%) patients died. There was a signifi cant difference in the estimated survival rate among the 3 groups stratified by Glasgow Prognostic Score. The estimated survival rate in the Group-1 was significantly higher than those in Groups 2 and 3. In the univariate analysis C-reactive protein, serum cytokeratin 19 fragment 21-1 and Glasgow Prognostic Score were significant predictors of overall survival. On the multivariate analysis, serum cytokeratin 19 fragment 21-1 and Glasgow Prognostic Score were independently associated with shorter overall survival. CONCLUSION: Our review suggests Glasgow Prognostic Score may play as a prognostic predictor for upper urinary urothelial carcinoma.


Assuntos
Carcinoma/sangue , Neoplasias Urológicas/sangue , Idoso , Idoso de 80 Anos ou mais , Antígenos de Neoplasias/sangue , Biomarcadores Tumorais/sangue , Proteína C-Reativa/análise , Carcinoma/patologia , Feminino , Humanos , Estimativa de Kaplan-Meier , Queratina-19/sangue , Masculino , Pessoa de Meia-Idade , Prognóstico , Modelos de Riscos Proporcionais , Valores de Referência , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade , Albumina Sérica/análise , Estatísticas não Paramétricas , Neoplasias Urológicas/patologia , Urotélio/patologia
5.
Elife ; 72018 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-29661272

RESUMO

Gram-negative bacteria import essential nutrients such as iron and vitamin B12 through outer membrane receptors. This process utilizes proton motive force harvested by the Ton system made up of three inner membrane proteins, ExbB, ExbD and TonB. ExbB and ExbD form the proton channel that energizes uptake through TonB. Recently, crystal structures suggest that the ExbB pentamer is the scaffold. Here, we present structures of hexameric complexes of ExbB and ExbD revealed by X-ray crystallography and single particle cryo-EM. Image analysis shows that hexameric and pentameric complexes coexist, with the proportion of hexamer increasing with pH. Channel current measurement and 2D crystallography support the existence and transition of the two oligomeric states in membranes. The hexameric complex consists of six ExbB subunits and three ExbD transmembrane helices enclosed within the central channel. We propose models for activation/inactivation associated with hexamer and pentamer formation and utilization of proton motive force.

6.
Pediatr Surg Int ; 31(10): 987-90, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26276429

RESUMO

There is a risk of developing a fatal trachea-innominate artery fistula following laryngotracheal separation for the prevention of intractable aspiration pneumonia. We developed a novel technique of surgical closure of the larynx to avoid this complication and provide long-term cannula-free care.


Assuntos
Fístula/prevenção & controle , Laringe/cirurgia , Pneumonia Aspirativa/complicações , Doenças da Traqueia/prevenção & controle , Criança , Humanos , Masculino
7.
Phys Chem Chem Phys ; 17(33): 21104-11, 2015 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-26147491

RESUMO

Surface-enhanced IR absorption spectroscopy (SEIRAS) is a powerful tool for studying the structure of molecules adsorbed on an electrode surface (ATR-SEIRA). Coupled with an electrochemical system, structural changes induced by changes in the electric field can be detected. All the membrane proteins are subjected to the effect of membrane electric field, but conformational changes at different membrane potentials and their functional relevance have not been studied extensively except for channel proteins. In this contribution, background information of potential-dependent functional and structural changes of a prototypical channel, the KcsA channel, is summarized, and SEIRAS applied to the KcsA channel under the application of the potential is shown. The potassium channels allow K(+) to permeate selectively through the structural part called the selectivity filter, in which dehydrated K(+) ions interact with backbone carbonyls. In the absence of K(+), the selectivity filter undergoes conformational changes to the non-conductive collapsed conformation. To apply the electric field, the KcsA channels were fixed on the gold surface in either upside or reverse orientation. The SEIRA spectrum in K(+) or Na(+) solution revealed both backbone structural changes and local changes in the OCO-carboxylate groups. Upon application of the negative electric field, the spectrum of OCO was enhanced only in the K(+) solution. These results indicate that the negative electric field accumulates local K(+) concentration, which turned the collapsed filter to the conductive conformation. ATR-SEIRA serves as an unprecedented experimental system for examining membrane proteins under an electric field.


Assuntos
Canais de Potássio/química , Espectrofotometria Infravermelho , Eletricidade , Bloqueadores dos Canais de Potássio/química , Bloqueadores dos Canais de Potássio/metabolismo , Canais de Potássio/metabolismo , Estrutura Terciária de Proteína , Compostos de Amônio Quaternário/química , Compostos de Amônio Quaternário/metabolismo
8.
Surg Endosc ; 29(4): 851-5, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25060685

RESUMO

BACKGROUND: Rectovesical fistula is a rare complication following prostatectomy, associated with significant symptoms such as urinary drainage from anus or faecaluria. While several surgical procedures have been described to treat this condition, none of them has been accepted as the universal standard. Transanal endoscopic microsurgery (TEM) is a well-established endoluminal procedure for local excision of rectal tumors. But its application to the repair of rectovesical fistula has been almost unknown. METHODS: We performed TEM as a surgical repair for refractory rectovesical fistula developing after radical prostatectomy in 10 patients. Under the magnified three-dimensional view, through the stereoscope, the fistula and the surrounding rectal mucosa were precisely resected. The defect and the muscle layer of the rectum were closed by hand-sew technique in four layers. RESULTS: Fistula was completely closed in 7 patients, who eventually underwent enterostomy closure, while in the other 3 patients the fistula recurred. In the three recurrent cases, the fistula was associated with wide, tough scar tissue due to previous irradiation, HIFU, or repeated surgical repair attempts. CONCLUSIONS: Rectovesical fistulas associated with wide, tough scar tissue due to multi-time attempt of surgical repair or any type of energy ablation should not be indicated for repair by TEM. However, for simple fistulas without tough, fibrotic surroundings, TEM can be indicated as a minimally invasive surgical option with very low morbidity, without any incision in healthy tissue for approach.


Assuntos
Microcirurgia/métodos , Cirurgia Endoscópica por Orifício Natural/métodos , Complicações Pós-Operatórias/cirurgia , Prostatectomia , Fístula Retal/cirurgia , Reto/cirurgia , Fístula da Bexiga Urinária/cirurgia , Idoso , Canal Anal , Humanos , Masculino , Pessoa de Meia-Idade , Prostatectomia/métodos , Fístula Retal/etiologia , Resultado do Tratamento , Fístula da Bexiga Urinária/etiologia
9.
Biochim Biophys Acta ; 1848(1 Pt A): 145-50, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25312694

RESUMO

KcsA is a pH-dependent potassium channel that is activated at acidic pH. The channel undergoes global conformational changes upon activation. We hypothesized that the open-close conformational changes of the transmem brane region could promote the flip-flop of phosphoiipids. Based on this hypothesis, we measured the flip-flop ofNBD-labeled phospholipids in KcsA-incorporated proteoliposomes. Both flip and flop rates of ~NBD-PC were significantly enhanced in the presence of KcsA and were several times higher at pH 4.0 than at pH 7.4, suggesting that KcsA promotes the phospholipid flip in a conformation-dependent manner. Phospholipids were nonselectively flipped with respect to the glycerophospholipid structure. In the active state of KcsA channel,tetrabutylammonium locks the channel in the open conformation at acidic pH; however, it did not alter the fliprate of CGNBD-PC. Thus, the open-close transition of the transmembrane region did not affect the flip-flop of phospholipids. In addition, the KcsA mutant that lacked anN-terminal amphipathic helix (MO-helix) was found to show reduced ability to fl ip C6NBD-phospholipids at acidic pH. The closed conformation is stabilized in the absence of MO-heli x, and thus the attenuated flip could be explained by the reduced prevalence of the open conformation.These results suggest that the open conformation of KcsA can disturb the bilayer integrity and facilitate the flip-flop of phospholipids.


Assuntos
Proteínas de Bactérias/química , Bicamadas Lipídicas/química , Fosfolipídeos/química , Canais de Potássio/química , 4-Cloro-7-nitrobenzofurazano/análogos & derivados , 4-Cloro-7-nitrobenzofurazano/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Colesterol/química , Colesterol/metabolismo , Concentração de Íons de Hidrogênio , Bicamadas Lipídicas/metabolismo , Modelos Moleculares , Mutação , Fosfatidilcolinas/química , Fosfatidilcolinas/metabolismo , Fosfolipídeos/metabolismo , Canais de Potássio/genética , Canais de Potássio/metabolismo , Ligação Proteica , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Compostos de Amônio Quaternário/química
10.
Cell Med ; 8(1-2): 31-8, 2015 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-26858906

RESUMO

To establish novel islet-based therapies, our group has recently developed technologies for creating functional neo-islet tissues in the subcutaneous space by transplanting monolithic sheets of dispersed islet cells (islet cell sheets). Improving cellular function and viability are the next important challenges for enhancing the therapeutic effects. This article describes the adenoviral vector-mediated gene transduction of dispersed islet cells under culture conditions. Purified pancreatic islets were obtained from Lewis rats and dissociated into single islet cells. Cells were plated onto laminin-5-coated temperature-responsive polymer poly(N-isopropylacrylamide)-immobilized plastic dishes. At 0 h, islet cells were infected for 1 h with either conventional type 5 adenoviral vector (Ad-CA-GFP) or fiber-modified adenoviral vector (AdK7-CA-GFP) harboring a polylysine (K7) peptide in the C terminus of the fiber knob. We investigated gene transduction efficiency at 48 h after infection and found that AdK7-CA-GFP yielded higher transduction efficiencies than Ad-CA-GFP at a multiplicity of infection (MOI) of 5 and 10. For AdK7-CA-GFP at MOI = 10, 84.4 ± 1.5% of islet cells were found to be genetically transduced without marked vector infection-related cellular damage as determined by viable cell number and lactate dehydrogenase (LDH) release assay. After AdK7-CA-GFP infection at MOI = 10, cells remained attached and expanded to nearly full confluency, showing that this adenoviral infection protocol is a feasible approach for creating islet cell sheets. We have shown that dispersed and cultured islet cells can be genetically modified efficiently using fiber-modified adenoviral vectors. Therefore, this gene therapy technique could be used for cellular modification or biological assessment of dispersed islet cells.

11.
Biophys Physicobiol ; 12: 37-45, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-27493853

RESUMO

The X-ray structure of KcsA, a eubacterial potassium channel, displays a selectivity filter composed of four parallel peptide strands. The backbone carbonyl oxygen atoms of these strands solvate multiple K(+) ions. KcsA structures show different distributions of ions within the selectivity filter in solutions containing different cations. To assess the interactions of cations with the selectivity filter, we used attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy. Ion-exchange-induced ATR-FTIR difference spectra were obtained by subtracting the spectrum of KcsA soaked in K(+) solution from that obtained in Li(+), Na(+), Rb(+), and Cs(+) solutions. Large spectral changes in the amide-I and -II regions were observed upon replacing K(+) with smaller-sized cations Li(+) and Na(+) but not with larger-sized cations Rb(+) and Cs(+). These results strongly suggest that the selectivity filter carbonyls coordinating Rb(+) or Cs(+) adopt a conformation similar to those coordinating K(+) (cage configuration), but those coordinating Li(+) or Na(+) adopt a conformation (plane configuration) considerably different from those coordinating K(+). We have identified a cation-type sensitive amide-I band at 1681 cm(-1) and an insensitive amide-I band at 1659 cm(-1). The bands at 1650, 1639, and 1627 cm(-1) observed for Na(+)-coordinating carbonyls were almost identical to those observed in Li(+) solution, suggesting that KcsA forms a similar filter structure in Li(+) and Na(+) solutions. Thus, we conclude that the filter structure adopts a collapsed conformation in Li(+) solution that is similar to that in Na(+) solution but is in clear contrast to the X-ray crystal structure of KcsA with Li(+).

12.
Plant Cell Physiol ; 54(7): 1027-40, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23737502

RESUMO

Water-soluble orange carotenoid proteins (OCPs) that bind 3'-hydroxyechinenone are found in cyanobacteria, and are thought to play a key role in photoprotection. The distribution of OCPs in eukaryotes remains largely unknown. In this study, we identified a novel OCP that predominantly binds astaxanthin from a eukaryotic microalga, strain Ki-4, isolated from a dry surface of heated asphalt in midsummer. A purified astaxanthin-binding OCP, named AstaP, shows high solubility in water with an absorption peak at 484 nm, and possesses a heat-stable activity that quenches singlet oxygen. The deduced amino acid sequence of AstaP comprises an N-terminal hydrophobic signal peptide, fasciclin domains found in secreted and cell surface proteins, and N-linked glycosylation sites, the first example of a carotenoprotein among fasciclin family proteins. AstaP homologs of unknown function are distributed mainly in organisms from the hydrosphere, such as marine bacteria, cyanobacteria, sea anemone and eukaryotic microalgae; however, AstaP exhibits a unique extraordinarily high isoelectric point (pI) value among homologs. The gene encoding AstaP, as well as the AstaP peptide, is expressed abundantly under conditions of dehydration and salt stress in conjunction with high light exposure. As a unique aqueous carotenoprotein, AstaP will provide a novel function of OCPs in protection against extreme photooxidative stresses.


Assuntos
Proteínas de Algas/metabolismo , Clorófitas/metabolismo , Hidrocarbonetos , Microalgas/metabolismo , Proteínas de Algas/classificação , Proteínas de Algas/genética , Sequência de Aminoácidos , Northern Blotting , Carotenoides/metabolismo , Clorófitas/citologia , Clorófitas/ultraestrutura , Cromatografia Líquida de Alta Pressão , Eletroforese em Gel de Poliacrilamida , Células Eucarióticas/metabolismo , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/efeitos da radiação , Luz , Espectrometria de Massas/métodos , Microalgas/citologia , Microalgas/isolamento & purificação , Microscopia Eletrônica de Varredura , Dados de Sequência Molecular , Estresse Oxidativo/efeitos da radiação , Filogenia , Ligação Proteica , Estações do Ano , Homologia de Sequência de Aminoácidos , Cloreto de Sódio/farmacologia , Solubilidade , Água/metabolismo , Xantofilas/metabolismo
13.
J Zoo Wildl Med ; 43(3): 632-5, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23082531

RESUMO

A necropsy was performed on an adult European lynx, Lynx lynx (Linnaeus, 1758), held in captivity until its death, to determine level of parasitism. Examination of the eyes revealed the oriental eyeworm, Thelazia callipaeda, in the conjunctival sac and the third eyelid of both eyes. The species was confirmed by location and morphology. Intact worms were fixed, mounted, and identified. Examination of the alimentary tract revealed the common ascaroid nematode, Toxocara cati. Species was confirmed by the arrow-like anterior end. One hundred and forty-one adult worms were collected. The presence of these nematodes indicated the importance of eliminating the contact of zoo animals with Amiota spp. vectors and to prevent contamination with the infective T. cati eggs.


Assuntos
Lynx , Infecções por Spirurida/veterinária , Thelazioidea/isolamento & purificação , Toxocara/isolamento & purificação , Toxocaríase/parasitologia , Animais , Animais de Zoológico , Evolução Fatal , Japão/epidemiologia , Masculino , Pneumonia/mortalidade , Pneumonia/veterinária , Infecções por Spirurida/epidemiologia , Infecções por Spirurida/parasitologia , Toxocara/classificação , Toxocaríase/epidemiologia
14.
Cell Transplant ; 21(2-3): 535-45, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22793062

RESUMO

Mizoribine (MZ) inhibits the differentiation and proliferation of helper T and B cells after antigen recognition by suppressing the purine biosynthesis pathway and nucleic acid synthesis. MZ has been used in kidney transplantation, but distinct data are unavailable for islet transplantation. The present study investigated the efficacy of MZ for islet xenotransplantation. Immunosuppressive effects of MZ were determined by mixed lymphocyte reaction (MLR) assay in vitro. Toxicities for Wistar rat islets were determined by adenosine triphosphate (ATP) contents of islets during 3-day culture and stimulation index in response to glucose after culture. Immunosuppressive effects in vivo were tested in a Wistar-to-B6 islet xenotransplantation model. MZ was administered continuously for 28 days subcutaneously or intramuscularly. MZ inhibited MLR response by approximately 50% at 0.1 µg/ml. ATP contents decreased with MZ >100 µg/ml, while stimulation index was maintained. Continuous infusion of MZ at 10 mg/kg maintained blood concentrations at 0.13-0.19 µg/ml, while intramuscular injection of MZ at 100 mg/kg/day (peak 520 µg/ml at 1 h postinjection) resulted in below measurable levels (<0.03 µg/ml) within 24 h. Graft survival was significantly prolonged following continuous infusion of 10 mg/kg/day compared to controls (31.0 ± 9.5 vs. 13.2 ± 5.2 days; p = 0.002). Furthermore, animals with intramuscular injection at doses of 3.2, 10, or 100 mg/kg/day showed significantly longer graft survival (20.0 ± 7.5, 22.0 ± 7.31, and 24.5 ± 8.1 days, respectively; p < 0.05 each). Histological examination showed significant suppression of lymphocyte infiltration by MZ administration. MZ showed immunosuppressive effects in an experimental islet xenotransplantation model without adverse effects on endocrine function of islet grafts.


Assuntos
Diabetes Mellitus Experimental/cirurgia , Imunossupressores/administração & dosagem , Transplante das Ilhotas Pancreáticas , Ilhotas Pancreáticas/citologia , Ribonucleosídeos/administração & dosagem , Trifosfato de Adenosina/metabolismo , Animais , Glicemia/análise , Células Cultivadas , Diabetes Mellitus Experimental/patologia , Sobrevivência de Enxerto/imunologia , Imunossupressores/toxicidade , Injeções Intramusculares , Injeções Subcutâneas , Ilhotas Pancreáticas/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Ratos , Ratos Wistar , Ribonucleosídeos/toxicidade , Transplante Heterólogo
15.
J Phys Chem Lett ; 3(24): 3806-10, 2012 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-26291114

RESUMO

The potassium channel is highly selective for K(+) over Na(+), and the selectivity filter binds multiple dehydrated K(+) ions upon permeation. Here, we applied attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy to extract ion-binding-induced signals of the KcsA potassium channel at neutral pH. Shifts in the peak of the amide-I signal towards lower vibrational frequencies were observed as K(+) was replaced with Na(+). These ion species-specific shifts deduced the selectivity filter as the source of the signal, which was supported by the spectra of a mutant for the selectivity filter (Y78F). The difference FTIR spectra between the solution containing various concentrations of K(+) and that containing pure Na(+) demonstrated two types of peak shifts of the amide-I vibration in response to the K(+) concentration. These signals represent the binding of K(+) ions to the different sites in the selectivity filter with different dissociation constants (KD = 9 or 18 mM).

16.
Transplantation ; 92(11): 1231-6, 2011 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-22124282

RESUMO

BACKGROUND: There remains a paucity of therapeutic approaches to completely treat diabetes mellitus. This study was designed to develop a dispersed islet cell-based tissue engineering approach to engineer functional neo-islet tissues in the absence of traditional bioabsorbable scaffold matrices. METHODS: Specialized coated plastic dishes were prepared by covalently immobilizing a temperature-responsive polymer, poly(N-isopropylacrylamide), onto the plastic followed by coating with laminin-5. Dispersed rat islet cells were plated on the laminin-5-poly(N-isopropylacrylamide) dishes. After 2 days of culturing, islet cells were harvested as a uniformly connected tissue sheet by lowering the culture temperature from 37°C to 20°C for 30 min. Two harvested islet cell sheets were transplanted into the subcutaneous space of streptozotocin-induced diabetic severe combined immunodeficiency (SCID) mice to engineer neo-islet tissues in vivo. Therapeutic effects were investigated after the tissue engineering procedures. RESULTS: In all of the diabetic SCID mice transplanted with the islet sheets, serum hyperglycemia was successfully reverted to a steady normoglycemic level. The recipient SCID mice demonstrated positive for serum rat C-peptide and elevated serum insulin levels. Moreover, the islet cell sheet-transplanted SCID mice demonstrated rapid glucose clearance and return of serum glucose levels after intraperitoneal glucose tolerance test. Histological examination revealed that the transplanted islet cell sheets were structured as flat clusters of islet tissues in which an active vascular network manifested within and surrounding the newly formed tissues. CONCLUSIONS: This study describes a new proof-of-concept therapeutic approach to engineer functional neo-islet tissues for the treatment of type 1 diabetes mellitus.


Assuntos
Diabetes Mellitus Experimental/cirurgia , Transplante das Ilhotas Pancreáticas/métodos , Ilhotas Pancreáticas/cirurgia , Engenharia Tecidual/métodos , Tecidos Suporte , Animais , Glicemia/metabolismo , Peptídeo C/sangue , Células Cultivadas , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/induzido quimicamente , Modelos Animais de Doenças , Insulina/sangue , Ilhotas Pancreáticas/citologia , Masculino , Camundongos , Camundongos SCID , Ratos , Ratos Endogâmicos Lew , Estreptozocina/efeitos adversos , Resultado do Tratamento
17.
FEBS Lett ; 584(18): 3995-9, 2010 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-20699099

RESUMO

A cytotoxic peptide, polytheonamide B (pTB), from marine sponge was examined for cytotoxic spectrum and specific activity to mammalian cells was demonstrated. pTB is composed of alternative D- and L-amino acid residues throughout the 48-mer peptide. This suggests the formation of a ß-helix similar to gramicidin channels. Planar bilayer experiments revealed that pTB forms monovalent cation-selective channels, being compatible with the inner pore diameter of ∼4Å for a ß-helical structure. pTB penetrated vectorially into the membrane, formed a channel by means of a single molecule, and remained in the membrane. These functional properties may account for specific cytotoxic activity.


Assuntos
Citotoxinas/química , Citotoxinas/farmacologia , Proteínas/química , Proteínas/farmacologia , Theonella/química , Sequência de Aminoácidos , Animais , Linhagem Celular Tumoral , Citotoxinas/isolamento & purificação , Células HeLa , Humanos , Camundongos , Dados de Sequência Molecular , Conformação Proteica , Proteínas/isolamento & purificação
18.
Res Dev Disabil ; 31(6): 1448-61, 2010 Nov-Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20638234

RESUMO

We taught seven preschoolers with developmental disabilities to point-and-click with a computer mouse. The computer-based training program consisted of three parts, based on a task analysis of the behavioral prerequisites to point-and-click. Training 1 was designed to shape moving the mouse. Training 2 was designed to build eye-hand coordination by teaching the children to move the on-screen cursor onto specific items on the screen. Training 3 was designed to teach pressing and releasing the mouse button. An instructor provided prompts and blocking to facilitate skill acquisition. A multiple baseline design across participants was used to evaluate the effectiveness of the training program. The results showed that all participants learned to point-and-click after exposure to the training program.


Assuntos
Periféricos de Computador , Instrução por Computador/métodos , Deficiências do Desenvolvimento/reabilitação , Educação Especial/métodos , Desempenho Psicomotor/fisiologia , Pré-Escolar , Deficiências do Desenvolvimento/fisiopatologia , Seguimentos , Humanos , Masculino , Destreza Motora/fisiologia
19.
Biomaterials ; 30(30): 5943-9, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19674781

RESUMO

The present study was designed to establish a novel tissue engineering approach for diabetes mellitus (DM) by fabricating a tissue sheet composed of pancreatic islet cells for in vivo transplantation. Pancreatic islet cell suspensions were obtained from Lewis rats, and plated onto temperature-responsive culture dishes coated with extracellular matrix (ECM) proteins. After the cells reached confluency, islet cells cultured on laminin-5 coated dishes were successfully harvested as a uniformly spread tissue sheet by lowering the culture temperature to 20 degrees C for 20 min. The functional activity of the islet cell sheets was confirmed by histological examination and Insulin secretion assay prior to in vivo transplantation. Histological examination revealed that the harvested islet cell sheet was comprised of insulin- (76%) and glucagon- (19%) positive cells, respectively. In vivo functionality of the islet cell sheet was maintained even 7 days after transplantation into the subcutaneous space of Lewis rats. The present study describes an approach to generate a functional sheet of pancreatic islet cells on laminin-5 coated temperature-responsive dishes, which can be subsequently transplanted in vivo. This study serves as the foundation for the creation of a novel cell-based therapy for DM to provide patients an alternative method.


Assuntos
Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/terapia , Transplante das Ilhotas Pancreáticas/instrumentação , Transplante das Ilhotas Pancreáticas/métodos , Ilhotas Pancreáticas/citologia , Animais , Moléculas de Adesão Celular/química , Transplante de Células , Matriz Extracelular/metabolismo , Glucagon/química , Glucagon/metabolismo , Insulina/metabolismo , Masculino , Microscopia Eletrônica/métodos , Ratos , Ratos Endogâmicos Lew , Temperatura Ambiente , Fatores de Tempo
20.
J Pediatr Surg ; 43(3): 583-5, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18358309

RESUMO

Congenital esophageal stenosis (CES) is a rare anomaly, and appropriate management is not well established. We performed myectomy of the esophageal wall in a child with critical esophageal stenosis caused by tracheobronchial remnant (TBR). An 18-month-old boy was admitted to our hospital having frequent vomiting and failure to thrive. Esophagography and esophagoscopy showed abrupt stenosis at the lower esophageal wall. Balloon dilatation was performed but was ineffective. Surgery was performed under a diagnosis of CES because of TBR. Cartilage was palpable in the stenotic esophageal wall, and extirpation of the muscular layer of the stenotic portion was performed, leaving the mucosal layer intact. The muscular layer was closed loosely using interrupted 5-0 absorbable sutures to match the oral and anal sides together. Postoperatively, the esophageal passage was improved to the point that the patient was able to take solid foods without vomiting. This successful outcome suggests that circular myectomy of the TBR is worth recommending as a surgical procedure for short segment and stenosis of patients with CES because of TBR.


Assuntos
Procedimentos Cirúrgicos do Sistema Digestório/métodos , Estenose Esofágica/congênito , Estenose Esofágica/cirurgia , Biópsia por Agulha , Brônquios/anormalidades , Cateterismo , Anormalidades do Sistema Digestório/diagnóstico por imagem , Anormalidades do Sistema Digestório/cirurgia , Estenose Esofágica/diagnóstico por imagem , Estenose Esofágica/patologia , Seguimentos , Humanos , Imuno-Histoquímica , Lactente , Masculino , Radiografia , Medição de Risco , Índice de Gravidade de Doença , Traqueia/anormalidades , Resultado do Tratamento
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