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1.
BMJ Mil Health ; 166(E): e73-e74, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31256003

RESUMO

Historically, if US soldiers at Camp Fuji become severely ill or suffer trauma, they are transported by the ground ambulance, as the doctor-led air ambulance in eastern Shizuoka has never been permitted to land at Camp Fuji. However, it is widely recognised that severely ill or traumatised patients require time-dependent medical management. It was therefore agreed to undertake a joint exercise between the US medical assets of Camp Fuji and the doctor helicopters in eastern Shizuoka prefecture in evacuating a simulated severely ill or traumatised US soldier. The aim of this article is to describe the background and rationale between this collaboration between the civilian Japanese air ambulance and the US medical assets in Camp Fuji.


Assuntos
Resgate Aéreo/normas , Internacionalidade , Militares/estatística & dados numéricos , Transferência de Pacientes/métodos , Resgate Aéreo/estatística & dados numéricos , Comportamento Cooperativo , Humanos , Japão , Transferência de Pacientes/estatística & dados numéricos , Ensino/estatística & dados numéricos , Estados Unidos
2.
AJNR Am J Neuroradiol ; 41(1): 86-91, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31806600

RESUMO

BACKGROUND AND PURPOSE: Parkinson disease is related to neurodegeneration and iron deposition in the substantia nigra pars compacta and nigrosome 1. However, visualization of nigrosome 1 via MR imaging is poor owing to the bilateral asymmetry, regardless of whether it is healthy. We focused on the magic angle and susceptibility effect and evaluated the anatomic slant structure of nigrosome 1 by tilting subjects' heads in the B0 direction. MATERIALS AND METHODS: To investigate the effectiveness of the magic angle, we tilted the volunteers' heads to the right and left in the B0 direction or not at all for evaluating correlations between the degree of head tilting and visualization of the right nigrosome 1 and left nigrosome 1 using 3D spoiled gradient-echo sequences with multiecho acquisitions. We evaluated the susceptibility of nigrosome 1 and the local field using quantitative susceptibility mapping to assess static magnetic field inhomogeneity. RESULTS: The heads tilted to the right and left showed significantly higher contrasts of nigrosome 1 and the substantia nigra pars compacta than the nontilted heads. No significant differences were observed in the visualization and susceptibility between the right nigrosome 1 and left nigrosome 1 for each head tilt. The effect of the magic angle was remarkable in the nontilted heads. This finding was supported by quantitative susceptibility mapping because the anatomic slant structure of nigrosome 1 was coherent between the axis of nigrosome 1 and the magic angle. CONCLUSIONS: The asymmetric visualization of nigrosome 1 is affected by the magic angle and susceptibility. The anatomic slant structure of nigrosome 1 causes these challenges in visualization.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Substância Negra/diagnóstico por imagem , Adulto , Feminino , Humanos , Masculino , Doença de Parkinson , Adulto Jovem
3.
Acta Otorhinolaryngol Ital ; 38(2): 103-108, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29967557

RESUMO

SUMMARY: We assessed the long-term outcomes of alternating chemoradiotherapy (ACRT) using 5-fluorouracil and cisplatin (FP) in 25 patients with stage II or advanced nasopharyngeal cancer treated at our institution between April 1999 and April 2010. Median follow-up duration was 87 months (range 2-189). According to the 2009 TNM classification (UICC), six patients were in stage II, nine in stage III, and 10 in stage IV. Treatment completion, response and five-year survival rates were retrospectively assessed. ACRT was performed with a first course of chemotherapy administered followed by the initial round of radiotherapy (36 Gy). Then, a second course of chemotherapy with additional radiotherapy (20-30 Gy) was administered, followed by a final third course of chemotherapy. For chemotherapy, 5-fluorouracil (5-FU, 800 mg/m2/24 h) was intravenously administered for five days, and cisplatin (CDDP, 50 mg/m2/24 h) was administered on the last two days. Treatment completion rate was 96% (24 of 25 cases), and the response rate was 100% (CR: 24 cases and PR: 1 case). Additionally, the five-year overall survival rate was 89.3%. We have demonstrated that ACRT is an effective regimen to treat nasopharyngeal cancer, revealing higher treatment completion, response, and five-year overall survival rates compared with other combinatorial radiotherapy and chemotherapy treatment regimens.


Assuntos
Quimiorradioterapia , Neoplasias Nasofaríngeas/terapia , Adolescente , Adulto , Idoso , Quimiorradioterapia/métodos , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Nasofaríngeas/mortalidade , Neoplasias Nasofaríngeas/patologia , Estadiamento de Neoplasias , Estudos Retrospectivos , Taxa de Sobrevida , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
4.
Int J Oral Maxillofac Surg ; 47(10): 1316-1321, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29843949

RESUMO

The sagittal split ramus osteotomy (SSRO) is generally associated with greater postoperative stability than the intraoral vertical ramus osteotomy (IVRO); however, it entails a risk of inferior alveolar nerve damage. In contrast, IVRO has the disadvantages of slow postoperative osseous healing and projection of the antegonial notch, but inferior alveolar nerve damage is believed to be less likely. The purposes of this study were to compare the osseous healing processes associated with SSRO and IVRO and to investigate changes in mandibular width after IVRO in 29 patients undergoing mandibular setback. On computed tomography images, osseous healing was similar in patients undergoing SSRO and IVRO at 1year after surgery. Projection of the antegonial notch occurred after IVRO, but returned to the preoperative state within 1year. The results of the study indicate that IVRO is equivalent to SSRO with regard to both bone healing and morphological recovery of the mandible.


Assuntos
Osteotomia Sagital do Ramo Mandibular/métodos , Prognatismo/cirurgia , Cicatrização/fisiologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognatismo/diagnóstico por imagem , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Resultado do Tratamento
5.
Am J Transplant ; 18(4): 832-842, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-28898528

RESUMO

Subcutaneous tissue is a promising site for islet transplantation, due to its large area and accessibility, which allows minimally invasive procedures for transplantation, graft monitoring, and removal of malignancies as needed. However, relative to the conventional intrahepatic transplantation site, the subcutaneous site requires a large number of islets to achieve engraftment success and diabetes reversal, due to hypoxia and low vascularity. We report that the efficiency of subcutaneous islet transplantation in a Lewis rat model is significantly improved by treating recipients with inhaled 50% oxygen, in conjunction with prevascularization of the graft bed by agarose-basic fibroblast growth factor. Administration of 50% oxygen increased oxygen tension in the subcutaneous site to 140 mm Hg, compared to 45 mm Hg under ambient air. In vitro, islets cultured under 140 mm Hg oxygen showed reduced central necrosis and increased insulin release, compared to those maintained in 45 mm Hg oxygen. Six hundred syngeneic islets subcutaneously transplanted into the prevascularized graft bed reversed diabetes when combined with postoperative 50% oxygen inhalation for 3 days, a number comparable to that required for intrahepatic transplantation; in the absence of oxygen treatment, diabetes was not reversed. Thus, we show oxygen inhalation to be a simple and promising approach to successfully establishing subcutaneous islet transplantation.


Assuntos
Diabetes Mellitus Experimental/terapia , Diabetes Mellitus Tipo 1/terapia , Transplante das Ilhotas Pancreáticas/métodos , Ilhotas Pancreáticas/citologia , Neovascularização Fisiológica , Oxigênio/administração & dosagem , Tela Subcutânea/irrigação sanguínea , Administração por Inalação , Animais , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , Feminino , Sobrevivência de Enxerto , Masculino , Oxigênio/metabolismo , Ratos , Ratos Endogâmicos Lew
7.
J Fish Biol ; 89(3): 1592-602, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27325563

RESUMO

A laboratory experiment was conducted by varying the undersurface area of nesting substratum and the number of females in an experimental tank to elucidate the determinants of the mating pattern in the stream goby, Rhinogobius sp. cross-band type. Males with larger nests tended to attract two or more females to their nest in a tank. Moreover, males spawned simultaneously with multiple females and entire brood cannibalism by males was rarely observed under a female-biased sex ratio. When males spawned with a single female with low fecundity, however, entire brood cannibalism occurred at a high frequency, suggesting that a male guarding a nest with fewer eggs consumes the brood. Therefore, spawning behaviour of females that leads to a large egg mass would decrease the risk of entire brood cannibalism. In this species, simultaneous spawning by multiple females in a nest serves as a female counter-measure against entire brood cannibalism. These results suggest that a conflict of interest between the sexes through brood cannibalism is a major determinant of simultaneous spawning.


Assuntos
Canibalismo , Comportamento de Nidação , Perciformes , Reprodução , Animais , Tamanho da Ninhada , Feminino , Masculino , Óvulo , Rios , Razão de Masculinidade , Comportamento Sexual Animal
8.
Minerva Endocrinol ; 40(2): 85-103, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25651758

RESUMO

The safety and effectiveness of islet transplantation has been proven through world-wide trials. However, acute and chronic islet loss has hindered the ultimate objective of becoming a widely used treatment option for type 1 diabetes. A large islet loss is attributed, in part, to the liver being a less-than-optimal site for transplantation. Over half of the transplanted islets are destroyed shortly after transplantation due to direct exposure to blood and non-specific inflammation. Successfully engrafted islets are continuously exposed to the liver micro-environment, a unique immune system, low oxygen tension, toxins and high glucose, which is toxic to islets, leading to premature islet dysfunction/death. Investigations have continued to search for alternate sites to transplant islets that provide a better environment for prolonged function and survival. This article gathers courses and conditions that lead to islet loss, from organ procurement through islet transplantation, with special emphasis on hypoxia, oxidative stress, and antigen non-specific inflammation, and reviews strategies using pharmacological agents that have shown effectiveness in protecting islets, including a new treatment approach utilizing siRNA. Pharmacological agents that support islet survival and promote ß-cell proliferation are also included. Treatment of donor pancreata and/or islets with these agents should increase the effectiveness of islets transplanted into extrahepatic sites. Furthermore, the development of methods designed to release these agents over an extended period, will further increase their efficacy. This requires the combined efforts of both islet transplant biologists and bioengineers.


Assuntos
Transplante das Ilhotas Pancreáticas/métodos , Fígado/cirurgia , Transplante Heterotópico/métodos , Indutores da Angiogênese/farmacologia , Indutores da Angiogênese/uso terapêutico , Animais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Hipóxia Celular/efeitos dos fármacos , Microambiente Celular , Avaliação Pré-Clínica de Medicamentos , Técnicas de Silenciamento de Genes , Peptídeo 1 Semelhante ao Glucagon/agonistas , Peptídeo 1 Semelhante ao Glucagon/farmacologia , Peptídeo 1 Semelhante ao Glucagon/uso terapêutico , Glucose/metabolismo , Sobrevivência de Enxerto/efeitos dos fármacos , Humanos , Imunossupressores/farmacologia , Imunossupressores/uso terapêutico , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Peptídeos e Proteínas de Sinalização Intercelular/uso terapêutico , Ilhotas Pancreáticas/efeitos dos fármacos , Fígado/citologia , Fígado/imunologia , Fígado/metabolismo , Camundongos , Especificidade de Órgãos , Estresse Oxidativo/efeitos dos fármacos , RNA Interferente Pequeno/farmacologia , RNA Interferente Pequeno/uso terapêutico , Inibidores Teciduais de Metaloproteinases/farmacologia , Inibidores Teciduais de Metaloproteinases/uso terapêutico , Obtenção de Tecidos e Órgãos/métodos
9.
Br J Pharmacol ; 171(21): 4879-89, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24923772

RESUMO

BACKGROUND AND PURPOSE: PGE2 is a major prostanoid that regulates inflammation by stimulating EP1-4 receptors. However, how PGE2 induces an initial inflammatory response to vascular hyper-permeability remains unknown. Here we investigated the role of the PGE2 -EP receptor signal in modulating vascular permeability both in vivo and in vitro. EXPERIMENTAL APPROACH: We used a modified Miles assay and intravital microscopy to examine vascular permeability in vivo. Endothelial barrier property was assessed by measuring transendothelial electrical resistance (TER) in vitro. KEY RESULTS: Local administration of PGE2 , an EP2 or EP4 receptor agonist into FVB/NJcl mouse ear skin caused vascular leakage, indicated by dye extravasation. Intravital microscopy and laser Doppler blood-flow imaging revealed that these treatments dilated peripheral vessels and increased local blood flow. Pretreatment with the vasoconstrictor phenylephrine inhibited the PGE2 -induced blood flow increase and vascular leakage. In contrast to the EP2 and EP4 receptor agonists, administration of an EP3 receptor agonist suppressed vascular leakage without altering vascular diameter or blood flow. In isolated HUVECs, the EP3 receptor agonist elevated TER and blocked thrombin-induced dextran passage. Inhibiting PKA restored the hypo-permeability induced by the EP3 receptor agonist. CONCLUSIONS AND IMPLICATIONS: Activation of the PGE2 -EP2 or -EP4 receptor signal induces vasodilatation in mural cells, resulting in increased local blood flow and hyper-permeability. In contrast, activation of the PGE2 -EP3 receptor signal induces a cAMP-dependent enhancement of the endothelial barrier, leading to hypo-permeability. We provide the first evidence that endothelial cells and mural cells cooperate to modulate vascular permeability.


Assuntos
Permeabilidade Capilar/fisiologia , Receptores de Prostaglandina E Subtipo EP2/metabolismo , Receptores de Prostaglandina E Subtipo EP3/metabolismo , Receptores de Prostaglandina E Subtipo EP4/metabolismo , Animais , Permeabilidade Capilar/efeitos dos fármacos , AMP Cíclico/metabolismo , Dinoprostona/farmacologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Camundongos , Receptores de Prostaglandina E Subtipo EP2/agonistas , Receptores de Prostaglandina E Subtipo EP3/agonistas , Receptores de Prostaglandina E Subtipo EP4/agonistas , Transdução de Sinais/efeitos dos fármacos , Pele/efeitos dos fármacos , Pele/metabolismo , Fator A de Crescimento do Endotélio Vascular/farmacologia , Vasodilatação/efeitos dos fármacos , Vasodilatação/fisiologia
10.
Am J Transplant ; 13(8): 2154-60, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23746308

RESUMO

Pancreatic islet transplantation is an attractive therapy for the treatment of insulin-dependent diabetes mellitus. However, the low efficiency of this procedure necessitating sequential transplantations of islets with the use of 2-3 donors for a single recipient, mainly due to the early loss of transplanted islets, hampers its clinical application. Previously, we have shown in mice that a large amount of HMGB1 is released from islets soon after their transplantation and that this triggers innate immune rejection with activation of DC, NKT cells and neutrophils to produce IFN-γ, ultimately leading to the early loss of transplanted islets. Thus, HMGB1 release plays an initial pivotal role in this process; however, its mechanism remains unclear. Here we demonstrate that release of HMGB1 from transplanted islets is due to hypoxic damage resulting from Ca(2+) influx into ß cells through the Na(+) /Ca(2+) exchanger (NCX). Moreover, the hypoxia-induced ß cell damage was prevented by pretreatment with an NCX-specific inhibitor prior to transplantation, resulting in protection and long-term survival of transplanted mouse and human islets when grafted into mice. These findings suggest a novel strategy with potentially great impact to improve the efficiency of islet transplantation in clinical settings by targeting donor islets rather than recipients.


Assuntos
Compostos de Anilina/farmacologia , Diabetes Mellitus Experimental/prevenção & controle , Diabetes Mellitus Tipo 1/imunologia , Rejeição de Enxerto/imunologia , Transplante das Ilhotas Pancreáticas/imunologia , Ilhotas Pancreáticas/imunologia , Éteres Fenílicos/farmacologia , Trocador de Sódio e Cálcio/antagonistas & inibidores , Animais , Diabetes Mellitus Experimental/enzimologia , Diabetes Mellitus Experimental/imunologia , Citometria de Fluxo , Rejeição de Enxerto/tratamento farmacológico , Rejeição de Enxerto/metabolismo , Proteína HMGB1/metabolismo , Humanos , Hipóxia/metabolismo , Hipóxia/patologia , Ilhotas Pancreáticas/efeitos dos fármacos , Ilhotas Pancreáticas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Camundongos SCID , Trocador de Sódio e Cálcio/metabolismo
11.
Acta Biomater ; 9(3): 5802-9, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23201016

RESUMO

The major functions required for load-bearing orthopaedic implants are load-bearing and mechanical or biological fixation with the surrounding bone. Porous materials with appropriate mechanical properties and adequate pore structure for fixation are promising candidates for load-bearing implant material. In previous work, the authors developed a novel titanium (Ti) foam sheet 1-2mm thick by an original slurry foaming method. In the present work, novel Ti foam is developed with mechanical properties compatible with cortical bone and biological fixation capabilities by layer-by-layer stacking of different foam sheets with volumetric porosities of 80% and 17%. The resulting multilayer Ti foam exhibited a Young's modulus of 11-12GPa and yield strength of 150-240MPa in compression tests. In vitro cell culture on the sample revealed good cell penetration in the higher-porosity foam (80% volumetric porosity), which reached 1.2mm for 21 days of incubation. Cell penetration into the high-porosity layers of a multilayer sample was good and not influenced by the lower-porosity layers. Calcification was also observed in the high-porosity foam, suggesting that this Ti foam does not inhibit bone formation. Contradictory requirements for high volumetric porosity and high strength were attained by role-sharing between the foam sheets of different porosities. The unique characteristics of the present multilayer Ti foam make them attractive for application in the field of orthopaedics.


Assuntos
Osso e Ossos/efeitos dos fármacos , Osso e Ossos/fisiologia , Titânio/farmacologia , Calcificação Fisiológica/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Força Compressiva/efeitos dos fármacos , Humanos , Microscopia de Fluorescência , Porosidade/efeitos dos fármacos , Pós , Resistência à Tração/efeitos dos fármacos
12.
J Biol Regul Homeost Agents ; 25(2): 195-202, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21880208

RESUMO

Periodontitis is a localized infectious disease caused by periodontopathic bacteria such as Porphyromonas gingivalis (P. gingivalis), and the severity correlates to significance of immune responses. Recently, it has been reported that periodontitis is associated with the development of systemic disease such as diabetes and atherosclerosis because of increasing invasion of oral pathogens to the circulation. However, the association between local and systemic infectious responses is still unclear. In the present study, we examined the differences of biological responses in animals with or without bacterial infection. After Balb/c mice were infected subcutaneously with live P. gingivalis W83, serum, skin and liver were collected according to experimental protocol. The skin and liver tissues were observed pathologically by haematoxylin-eosin staining, and serum IL-6 levels were measured using ELISA method. Throughout the experimental period, conditions of the mice were observed continuously. As expected, severe infiltration of leukocytes were observed at inflamed skin corresponding to the number of bacterial challenges. Although no inflammatory appearance of skin was observed, serum IL-6 levels were increased dramatically (P <0.01, Student's t-test) and liver tissues were injured in the mice without bacterial challenge. Interestingly, although severe inflammatory appearance of the skin was observed, serum IL-6 levels were not increased and no inflammatory responses were observed in the liver of the 3-times bacterially challenged group. Importantly, immunoglobulin G against P. gingivalis W83 was detected in the blood of mice with 3-times bacterial challenge corresponding to improvement of weight loss and survival. In conclusion, although multiple infections develop severe localized inflammation, the immune system should be sufficient to protect the systemic inflammatory responses.


Assuntos
Infecções por Bacteroidaceae/imunologia , Imunidade Celular , Imunidade Humoral , Fígado/imunologia , Porphyromonas gingivalis/crescimento & desenvolvimento , Pele/imunologia , Animais , Anticorpos Antibacterianos/sangue , Infecções por Bacteroidaceae/microbiologia , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Histocitoquímica , Imunoglobulina G/análise , Imunoglobulina G/sangue , Injeções Subcutâneas , Interleucina-6/sangue , Fígado/microbiologia , Fígado/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Periodontite/imunologia , Periodontite/microbiologia , Pele/microbiologia , Pele/patologia
13.
Diabetologia ; 54(8): 2056-66, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21567299

RESUMO

AIMS/HYPOTHESIS: TNF-α plays important roles in the pathogenesis of type 1 and type 2 diabetes mellitus. In light of this, we examined the involvement of a pro-apoptotic gene, BBC3 (also known as PUMA), in TNF-α-mediated beta cell dysfunction and destruction in human islets. METHODS: Human islets were exposed in vitro to TNF-α alone or in combination with IFN-γ. Gene expression was assessed by RT-PCR using a set of single islets. Protein abundance and cellular localisation of BBC3 were assessed by immunoblot and immunohistochemistry. A marginal number of islets were transplanted into diabetic NODscid mice to correlate in vivo islet function with BBC3 expression. RESULTS: BBC3 and IL8 mRNA were upregulated in TNF-α-stimulated islets in a dose-dependent manner and enhanced through addition of IFN-γ, but not upregulated by IFN-γ alone. Immunohistochemistry revealed that TNF-α in combination with IFN-γ upregulated basal BBC3 abundance in the cytoplasm of beta cells along with the perinuclear clustering of mitochondria partially co-localised with BBC3. TNF-α alone did not induce beta cell death, but did abrogate preproinsulin precursor mRNA synthesis in response to high glucose stimulation, which was inversely associated with upregulation of BBC3 mRNA expression by TNF-α. Higher BBC3 mRNA expression in islets correlated with decreased graft function in vivo. CONCLUSIONS/INTERPRETATION: These results suggest that BBC3 mRNA can serve as a molecular marker to detect early TNF-α-induced beta cell stress and may help identify islet-protective compounds for the treatment of diabetes.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Morte Celular/efeitos dos fármacos , Ilhotas Pancreáticas/efeitos dos fármacos , Ilhotas Pancreáticas/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Adulto , Idoso , Animais , Proteínas Reguladoras de Apoptose/genética , Western Blotting , Células Cultivadas , Feminino , Citometria de Fluxo , Humanos , Imuno-Histoquímica , Técnicas In Vitro , Células Secretoras de Insulina/citologia , Células Secretoras de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/metabolismo , Interferon gama/farmacologia , Interleucina-8/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Pessoa de Meia-Idade , Proteínas Proto-Oncogênicas/genética , Adulto Jovem
14.
J Dent Res ; 88(12): 1119-24, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19892919

RESUMO

Phosphoinositide-dependent kinase (PDK1) plays a central role in signal transduction mediated by phosphatidylinositol 3-kinases (PI3K) and regulates cellular functions in neutrophils. Neutrophils from individuals diagnosed with localized aggressive periodontitis (LAP) present an in vivo phenotype with depressed chemotaxis. The aim of this study was to test the hypothesis that PDK1 regulates chemotaxis in neutrophils and is responsible for the abnormal neutrophil chemotaxis LAP. Neutrophil chemotaxis was significantly suppressed by the PDK1 inhibitor staurosporine. When cells were transfected with PDK1 siRNA, there was a significant reduction in chemotaxis, while superoxide generation was not significantly affected. In primary neutrophils from persons with LAP, PDK1 expression and activation levels were significantly reduced, and this reduction was associated with the reduced phosphorylation of Akt (Thr308) and chemotaxis. Analysis of these data demonstrates that PDK1 is essential for the chemotactic migration of neutrophils, and in the absence of PDK1, neutrophil chemotaxis is impaired.


Assuntos
Quimiotaxia de Leucócito/fisiologia , Neutrófilos/enzimologia , Proteínas Serina-Treonina Quinases/fisiologia , Proteínas Quinases Dependentes de 3-Fosfoinositídeo , Periodontite Agressiva/enzimologia , Periodontite Agressiva/patologia , Western Blotting , Células Cultivadas , Quimiotaxia de Leucócito/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Ativação Enzimática/genética , Inibidores Enzimáticos/farmacologia , Regulação Enzimológica da Expressão Gênica , Inativação Gênica , Humanos , Neutrófilos/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/análise , Fosfatidilinositol 3-Quinases/efeitos dos fármacos , Fosforilação , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/genética , Proteínas Proto-Oncogênicas c-akt/análise , Proteínas Proto-Oncogênicas c-akt/efeitos dos fármacos , RNA Interferente Pequeno/genética , Serina/análise , Serina/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Estaurosporina/farmacologia , Superóxidos/análise , Superóxidos/metabolismo , Temperatura , Treonina/análise , Treonina/efeitos dos fármacos , Fatores de Tempo
15.
Br J Pharmacol ; 155(8): 1214-23, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18806821

RESUMO

BACKGROUND AND PURPOSE: The inflammation-resolving lipid mediator resolvin E1 (RvE1) effectively stops inflammation-induced bone loss in vivo in experimental periodontitis. It was of interest to determine whether RvE1 has direct actions on osteoclast (OC) development and bone resorption. EXPERIMENTAL APPROACH: Primary OC cultures derived from mouse bone marrow were treated with RvE1 and analysed for OC differentiation, cell survival and bone substrate resorption. Receptor binding was measured using radiolabelled RvE1. Nuclear factor (NF)-kappaB activation and Akt phosphorylation were determined with western blotting. Lipid mediator production was assessed with liquid chromatography tandem mass spectrometry. KEY RESULTS: OC growth and resorption pit formation were markedly decreased in the presence of RvE1. OC differentiation was inhibited by RvE1 as demonstrated by decreased number of multinuclear OC, a delay in the time course of OC development and attenuation of receptor activator of NF-kappaB ligand-induced nuclear translocation of the p50 subunit of NF-kappaB. OC survival and apoptosis were not altered by RvE1. Messenger RNA for both receptors of RvE1, ChemR23 and BLT(1) is expressed in OC cultures. Leukotriene B(4) (LTB(4)) competed with [(3)H]RvE1 binding on OC cell membrane preparations, and the LTB(4) antagonist U75302 prevented RvE1 inhibition of OC growth, indicating that BLT(1) mediates RvE1 actions on OC. Primary OC synthesized the RvE1 precursor 18R-hydroxy-eicosapentaenoic acid and LTB(4). Co-incubation of OC with peripheral blood neutrophils resulted in transcellular RvE1 biosynthesis. CONCLUSIONS AND IMPLICATIONS: These results indicate that RvE1 inhibits OC growth and bone resorption by interfering with OC differentiation. The bone-sparing actions of RvE1 are in addition to inflammation resolution, a direct action in bone remodelling.


Assuntos
Reabsorção Óssea , Diferenciação Celular/fisiologia , Ácido Eicosapentaenoico/análogos & derivados , Inflamação/prevenção & controle , Osteoclastos/citologia , Animais , Apoptose , Células Cultivadas , Dentina/metabolismo , Ácido Eicosapentaenoico/biossíntese , Ácido Eicosapentaenoico/fisiologia , Leucotrieno B4/biossíntese , Camundongos , Osteoclastos/metabolismo , Ensaio Radioligante
17.
Transplant Proc ; 40(2): 390-2, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18374078

RESUMO

UNLABELLED: Pancreas preservation using an oxygenated two-layer method (TLM) has been reported to improve islet yields, as has supplementation of Liberase with Pefabloc. We hypothesized that using both TLM and Pefabloc could enhance islet yield as compared with preservation in University of Wisconsin (UW) or Histidine-Tryptophan Ketoglutarate (HTK) solution. METHODS: Ninety-eight pancreata with no significant differences of age, body mass index, or cold ischemia time preserved randomly with UW (n = 40), TLM (n = 48), or HTK (n = 10) were processed with (n = 36) or without (n = 66) Pefabloc. RESULTS: The total islet equivalent (IEQ) from TLM-preserved pancreata processed with Pefabloc (n = 12) showed lower yields versus those processed without Pefabloc (n = 36): 216,120 +/- 27,906 vs. 301,427 +/- 21,447 IEQ (P < .05). Islets from 1 of 12 (8.33%) pancreata processed with Pefabloc in TLM were transplanted, in contrast with 15/36 TLM (41.67%) pancreata processed without it. Islet yields were not significantly different among pancreata preserved in UW and processed with Pefabloc (n = 17) versus without Pefabloc (n = 23): 342,693 +/- 45,588 versus 266,609 +/- 29,006 IEQ (P = .149). The number of transplants from UW-preserved pancreata was 3/17 (17.65%) when processed with Pefabloc and 4/23 (17.39%) without. Among the HTK group, there was no significant difference in islet yields between pancreata processed with (n = 7) versus without Pefabloc (n = 3): 248,227 +/- 65,294 versus 483,555 +/- 144,070 IEQ (P = .118). CONCLUSIONS: Pefabloc showed no benefit to improve islet yields. Pancreata preserved in TLM provided better transplant quality islets when processed in the absence of Pefabloc.


Assuntos
Ilhotas Pancreáticas/citologia , Soluções para Preservação de Órgãos , Inibidores de Proteases/uso terapêutico , Adenosina , Alopurinol , Cadáver , Contagem de Células , Feminino , Glucose , Glutationa , Humanos , Insulina , Ilhotas Pancreáticas/efeitos dos fármacos , Ilhotas Pancreáticas/fisiologia , Masculino , Manitol , Pessoa de Meia-Idade , Preservação de Órgãos/métodos , Tamanho do Órgão , Consumo de Oxigênio , Pâncreas , Cloreto de Potássio , Procaína , Rafinose , Doadores de Tecidos
18.
Am J Transplant ; 7(5): 1224-32, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17331110

RESUMO

The activation of p38 mitogen-activated protein kinase (MAPK) has been shown to cause ischemia/reperfusion injury of several organs used for transplantation and also to play a significant role in primary islet graft nonfunction. Activation of p38 MAPK may also occur during islet cryopreservation and thawing. In this study, a p38 MAPK inhibitor (p38IH) was applied to human islet cryopreservation to improve islet yield and quality after thawing. Under serum-free conditions, human islets were cryopreserved, thawed and cultured using our standard procedures. Three types of solutions were tested: conventional RPMI1640 medium (RPMI), a newly developed islet cryopreservation solution (ICS), and ICS supplemented with a p38IH, SD-282 (ICS-p38IH). Activation or inhibition of p38 MAPK was demonstrated by the diminished phosphorylation of HSP27 substrate. Islet recovery on day 2 after thawing was highest with ICS-p38IH and islet viability was not significantly different in the three groups. beta Cell numbers and function were the highest in islets cryopreserved with ICS-p38IH. Glucose-stimulated human C-peptide levels were 86% of that of the nonfrozen islets when measured 4 weeks after transplantation into NODscid mice. This improvement may provide an opportunity to establish islet banks and allow the use of cryopreserved islets for clinical transplantation.


Assuntos
Criopreservação/métodos , Inibidores Enzimáticos/farmacologia , Indóis/farmacologia , Ilhotas Pancreáticas/efeitos dos fármacos , Preservação de Órgãos/métodos , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Animais , Peptídeo C/metabolismo , Contagem de Células , Sobrevivência Celular , Células Cultivadas , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/cirurgia , Glucose/farmacologia , Humanos , Insulina/metabolismo , Ilhotas Pancreáticas/citologia , Ilhotas Pancreáticas/metabolismo , Transplante das Ilhotas Pancreáticas/métodos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
19.
Kidney Int ; 69(9): 1626-32, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16672924

RESUMO

Although uremia is well known as the most common cause of pruritus, the mechanisms of pruritus in chronic hemodialysis patients remain unclear. The purpose was to characterize uremic pruritus in more detail and to investigate whether severe pruritus is a marker for poor prognosis. A total of 1773 adult hemodialysis patients were studied. A questionnaire was given to each patient to assess the intensity and frequency, as well as pruritus-related sleep disturbance. We analyzed the relationship between clinical and laboratory data and the severity of pruritus in hemodialysis patients and followed them for 24 months prospectively. In total, 453 patients had severe pruritus with a visual analogue scale (VAS) score more than or equal to 7.0. Among them, more than 70% complained of sleep disturbance, whereas the majority of patients with a VAS score of less than 7.0 had no sleep disturbance. Male gender, high levels of blood urea nitrogen, beta2-microglobulin (beta2MG), hypercalcemia, and hyperphosphatemia were identified as independent risk factors for the development of severe pruritus, whereas a low level of calcium and intact-parathyroid hormone were associated with reduced risk. During the follow-up, 171 (9.64%) patients died. The prognosis of patients with severe pruritus was significantly worse than the others. Moreover, severe pruritus was independently associated with death even after adjusting for other clinical factors including diabetes mellitus, age, beta2MG, and albumin. Severe uremic pruritus caused by multiple factors, not only affects the quality of life but may also be associated with poor outcome in chronic hemodialysis patients.


Assuntos
Prurido/epidemiologia , Prurido/etiologia , Diálise Renal , Uremia/complicações , Uremia/terapia , Idoso , Biomarcadores/sangue , Nitrogênio da Ureia Sanguínea , Feminino , Humanos , Hipercalcemia/sangue , Masculino , Pessoa de Meia-Idade , Fosfatos/sangue , Prognóstico , Fatores de Risco , Transtornos do Sono-Vigília/diagnóstico , Resultado do Tratamento , Microglobulina beta-2/sangue
20.
Protein Eng Des Sel ; 19(7): 337-43, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16714338

RESUMO

Type I secretion system (TISS) of Gram-negative bacteria permits proteins to be secreted directly from the cytoplasm to the external medium by a single, energy-coupled step. To examine whether this system can be used as an extracellular production system of recombinant proteins, Escherichia coli alkaline phosphatase (AP) was fused to a C-terminal region of Pseudomonas sp. MIS38 lipase (PML) and examined for secretion using the E.coli cells carrying the heterologous TISS. PML is one of the passenger proteins of TISS and contains 12 repetitive sequences and a secretion signal at the C-terminal region. The fusion protein was efficiently secreted to the extracellular medium, while AP was not secreted at all, indicating that the secretion of AP is promoted by a secretion signal of PML. The repetitive sequences were not so important for secretion of the fusion protein, because the secretion level of the fusion protein containing entire repeats ( approximately 10 mg/l culture) was only 2-fold higher than that of the fusion protein without repeats. The fusion protein purified from the culture supernatant existed as a homodimer, like AP, and was indistinguishable from AP in enzymatic properties and stability.


Assuntos
Fosfatase Alcalina/metabolismo , Escherichia coli/enzimologia , Matriz Extracelular/metabolismo , Fosfatase Alcalina/genética , Fosfatase Alcalina/isolamento & purificação , Sequência de Bases , Dicroísmo Circular , Eletroforese em Gel de Poliacrilamida , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/isolamento & purificação , Proteínas de Escherichia coli/metabolismo , Lipase/metabolismo , Dados de Sequência Molecular , Fosforilação , Pseudomonas/enzimologia , Pseudomonas/genética , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/isolamento & purificação , Proteínas Recombinantes de Fusão/metabolismo , Espectrofotometria Ultravioleta , Temperatura
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