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1.
Obes Sci Pract ; 3(4): 446-452, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29259803

RESUMO

Background: Circulating microRNAs are emerging as potential prognostic biomarkers for the development of type 2 diabetes. However, microRNAs are also associated with complications from impaired glucose metabolism (e.g. endothelial cell function). Prior studies have not evaluated for associations between trajectories of circulating microRNAs with trajectories of fasting blood glucose over time and the responses to behavioral interventions to reduce risk. This study performed longitudinal assessment of microRNAs and fasting blood glucose and identified relationships between microRNAs and behavioral risk reduction interventions. Methods: MicroRNAs (n = 353) were measured in subsets (n = 10, n = 8) of participants from previously completed clinical trials that studied behavioral risk reduction interventions. Fasting blood glucose trajectories were associated with changes in 45 microRNAs over 12 months. Results: Following a 3-month physical activity and dietary intervention compared with baseline, 13 microRNAs were differentially expressed. Seven microRNAs (i.e. miR-106b, miR-20b, miR-363, miR-486, miR-532, miR-92a and miR-93) were commonly identified between the two analyses. Conclusions: Further studies are needed to determine which microRNAs are prognostic biomarkers of risk for type 2 diabetes versus consequences of impaired glucose metabolism. Additional future directions of this research are to differentiate whether microRNAs are prognostic and/or diagnostic biomarkers for risk for type 2 diabetes and predictive biomarkers of responses to risk reduction interventions.

2.
Scand J Med Sci Sports ; 23(5): e313-9, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23662804

RESUMO

To investigate the high-energy phosphate metabolism by (31) P-nuclear magnetic resonance spectroscopy during off-transition of exercise in different muscle groups, such as calf muscles and biceps femoris muscles, seven male long-distance runners (LDR) and nine untrained males (UT) performed both submaximal constant and incremental exercises. The relative exercise intensity was set at 60% of the maximal work rate (60%W max) during both knee flexion and plantar flexion submaximal constant load exercises. The relative areas under the inorganic phosphate (Pi ) and phosphocreatine (PCr) peaks were determined. During the 5-min recovery following the 60%W max, the time constant for the PCr off-kinetics was significantly faster in the plantar flexion (LDR: 17.3 ± 3.6 s, UT: 26.7 ± 6.7 s) than in the knee flexion (LDR: 29.7 ± 4.7 s, UT: 42.7 ± 2.8 s, P < 0.05). In addition, a significantly faster PCr off-kinetics was observed in LDR than in UT for both exercises. The ratio of Pi to PCr (Pi /PCr) during exercise was significantly lower during the plantar flexion than during the knee flexion (P < 0.01). These findings indicated that the calf muscles had relatively higher potential for oxidative capacity than that of biceps femoris muscles with an association of training status.


Assuntos
Exercício Físico/fisiologia , Músculo Esquelético/metabolismo , Consumo de Oxigênio/fisiologia , Fosfocreatina/biossíntese , Corrida/fisiologia , Trifosfato de Adenosina/metabolismo , Análise de Variância , Metabolismo Energético/fisiologia , Humanos , Perna (Membro)/fisiologia , Espectroscopia de Ressonância Magnética/métodos , Masculino , Contração Muscular/fisiologia , Adulto Jovem
3.
Radiol Med ; 116(2): 211-8, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20574708

RESUMO

PURPOSE: It has been reported that the prognosis differs between patients who have collagen vascular diseaseassociated interstitial pneumonia (CVD-IP) and those with idiopathic IP (IIP). In this study, chest computed tomography (CT) findings were compared between patients with CVD-IP and IIP. MATERIALS AND METHODS: A retrospective analysis was performed of 47 consecutive patients (23 with CVD-IP and 24 with IIP). The lower-lobe volume (LLV), total lung volume (TLV), and their ratio (LLV/TLV) were determined by volumetry using three-dimensional computed tomography (CT). RESULTS: There was no significant difference of the LLV/TLV ratio between the CVD-IP and IIP groups. However, the LLV/TLV ratio was <0.33 in 9/23 patients with CVD-IP versus 2/24 patients with IIP, and there was a significant difference in the percentage of patients with a ratio<0.33 between the CVD-IP and IIP groups (p = 0.01). The LLV/TLV ratio was not influenced by the severity of lung disease. CONCLUSIONS: Measuring the LLV/TLV ratio by threedimensional CT can help distinguish between CVD-IP and IIP at initial diagnosis, especially in patients with CVD-IP who have pulmonary involvement before other organ diseases and symptoms caused by CVD.


Assuntos
Doenças do Colágeno/diagnóstico por imagem , Imageamento Tridimensional , Doenças Pulmonares Intersticiais/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Doenças Vasculares/diagnóstico por imagem , Idoso , Estudos de Casos e Controles , Doenças do Colágeno/patologia , Feminino , Humanos , Doenças Pulmonares Intersticiais/patologia , Medidas de Volume Pulmonar , Masculino , Pessoa de Meia-Idade , Prognóstico , Testes de Função Respiratória , Estudos Retrospectivos , Doenças Vasculares/patologia
4.
J Sports Med Phys Fitness ; 48(2): 129-37, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18427405

RESUMO

AIM: It was the purpose of the investigation to determine whether an altered work rate could influence the oxygen uptake (V.O(2)) and heart rate (HR) dynamics at hypoxia and normoxia. METHODS: Ten males performed a cycle exercise with 2 repetitions of 6 min each at a constant work load while breathing one of two inspiratory O(2) fractions (FIO(2)): 0.12 (moderate hypoxia) and 0.21 (normoxia). Each test began with unloaded pedaling. This was followed by three constant loads, which were 40%, 60%, and 80% of the subject's gas exchange threshold (GET) in hypoxia (F(I)O(2) = 0.12), with the 80% GET load repeated under normoxia (room air). V.O(2) was measured on a breath-by-breath basis and beat-by-beat HR via ECG, and the half time (t1/2) of each parameter was established, following interpolation data. RESULTS: There were no remarkable differences in t1/2 V.O(2) dynamics among the 40%, 60% and 80% GET; however, the differences became significant at hypoxia compared with normoxia. The HR dynamics were significantly faster in normoxia compared with hypoxia, independent of work rates. During steady-state exercise, the alterations in HR and cardiac output (Q) using the acetylene rebreathing method depended on increases in the work rate, and a significantly increase in at 80% GET was observed when compared with normoxia. Increases of stroke volume (SV) were unaffected by altered work rates and inspired O(2) concentrations. The arteriovenous oxygen difference (Ca-vO(2)) at a steady-state of exercise increased proportionally with the work rate under hypoxia, and a much greater Ca-vO(2) was observed during normoxic exercise than under hypoxia. CONCLUSION: These results seem to suggest that in humans, O(2) uptake dynamics are affected by lower O(2), not by changing work rates at hypoxia, to which the interaction between lower O(2) utilization in exercising muscles and hypoxic-induced greater blood flow can be attributed.


Assuntos
Hipóxia/fisiopatologia , Consumo de Oxigênio/fisiologia , Adulto , Débito Cardíaco/fisiologia , Teste de Esforço , Frequência Cardíaca/fisiologia , Humanos , Masculino , Oxigênio/sangue
5.
Eur Respir J ; 32(1): 105-12, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18321934

RESUMO

Clock genes regulate mammalian circadian rhythms, and dysfunction of clock genes can contribute to various disorders. To investigate whether obstructive sleep apnoea syndrome (OSAS) influences clock gene function, the present authors examined Period1 (Per1) mRNA expression in vitro and in vivo. In eight healthy subjects and eight OSAS patients, plasma noradrenaline, serum interleukin (IL)-6, high-sensitivity C-reactive protein (hsCRP) and Per1 mRNA expression in peripheral whole blood were measured. Expression of Per1 mRNA in cultured cells was examined under IL-6 or noradrenaline stimulation in vitro. After noradrenaline was administered to mice in vivo, Per1 mRNA expression in the brain was examined. The concentrations of serum IL-6, hsCRP and plasma noradrenaline were elevated in OSAS patients, but improved by continuous positive airway pressure (CPAP) therapy. Per1 mRNA expression in the peripheral blood significantly decreased at 02:00 h by CPAP in OSAS patients. Stimulation with IL-6 did not directly induce Per1 mRNA in vitro. Administration of noradrenaline induced Per1 mRNA in the cerebral cortex of mice in vivo. The current study revealed that obstructive sleep apnoea syndrome caused clock gene dysfunction, and continuous positive airway pressure helped to improve it. Sympathetic activation and elevation of the plasma noradrenaline concentration in obstructive sleep apnoea syndrome may be one of the factors involved in disorders of Period1 mRNA expression.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Transtornos Cronobiológicos/genética , Ritmo Circadiano/genética , Proteínas Nucleares/metabolismo , Síndromes da Apneia do Sono/complicações , Adulto , Animais , Estudos de Casos e Controles , Proteínas de Ciclo Celular/genética , Células Cultivadas , Transtornos Cronobiológicos/terapia , Pressão Positiva Contínua nas Vias Aéreas , Feminino , Fibroblastos , Humanos , Interleucina-6/fisiologia , Leucócitos , Masculino , Camundongos , Pessoa de Meia-Idade , Norepinefrina/fisiologia , Proteínas Nucleares/genética , Proteínas Circadianas Period , RNA Mensageiro/metabolismo
6.
Eur Respir J ; 23(6): 885-90, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15219002

RESUMO

In order to examine the pathology in patients with obstructive sleep apnoea/hypopnoea syndrome (OSAHS), the nonlinear properties of respiratory movement and breath-to-breath variations during resting wakefulness with eyes closed was investigated. Recording of the respiratory movement using inductive plethysmography was performed on 14 patients with OSAHS and 13 control subjects for 2 h in the supine position during daytime. To calculate the correlation dimension (D2) for respiratory movement, an algorithm proposed by Grassberger and Procaccia was applied. The indices of breath-to-breath variations were estimated. To calculate D2 and breath-to-breath variations, two different segments were selected (200 s each). The value of D2 for respiratory movement in patients with OSAHS was significantly greater than that in control subjects. In the case of > or = 2.0 of D2 for respiratory movement, the sensitivity and specificity of detecting the presence of OSAHS was 85.7% and 76.9%, respectively. On the basis of breath-to-breath variations, only the coefficient of variation of expiratory time for respiratory movement in patients with OSAHS was significantly greater than that in the control subjects. In conclusion, the measurements of correlation dimensions for respiratory movement with a brief period during wakefulness may be a useful index for identifying patients with obstructive sleep apnoea/hypopnoea syndrome.


Assuntos
Mecânica Respiratória/fisiologia , Apneia Obstrutiva do Sono/fisiopatologia , Adulto , Algoritmos , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Dinâmica não Linear , Pletismografia , Análise de Regressão , Estatísticas não Paramétricas , Decúbito Dorsal , Vigília
7.
Med Eng Phys ; 25(5): 419-24, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12711240

RESUMO

This study describes the method of determination of the position and orientation of artificial knee implants using a single-plane radiograph. To simplify the 3D/2D matching problem, we proposed to use small markers embedded in a bone. From the image coordinates of markers, it is possible to estimate the position and orientation of implants if the relationship between the markers and the implant is known. The results of the in vitro experiment showed that rms errors in in-plane/out-of-plane translations and rotations were 0.2/2.3 mm and 0.2/0.2 degrees, respectively.


Assuntos
Análise de Falha de Equipamento/métodos , Imageamento Tridimensional/métodos , Articulação do Joelho/diagnóstico por imagem , Articulação do Joelho/fisiopatologia , Prótese do Joelho , Algoritmos , Estudos de Viabilidade , Humanos , Imageamento Tridimensional/instrumentação , Articulação do Joelho/cirurgia , Movimento (Física) , Movimento , Imagens de Fantasmas , Postura , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Reprodutibilidade dos Testes , Rotação , Sensibilidade e Especificidade
8.
Clin Exp Immunol ; 131(2): 248-53, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12562384

RESUMO

Human retinal pigment epithelial (RPE) cells form part of the blood-retina barrier where they potentially can regulate leucocyte function. RPE cells are known to secrete several cytokines in response to stimulation by other cytokines. Anaphylatoxin C5a, a potent inflammatory mediator produced during complement activation, binds to G-protein coupled C5a receptors (C5aR) on monocytes/macrophages and releases various cytokines from the cells. We previously reported that the human RPE cell line ARPE-19 possesses C5aR and expresses IL-8 mRNA in response to C5a stimulation. In this study, we used a primary human RPE cell line (RPE43) and found that C5a induces increased expression of IL-1beta, IL-6, MCP-1 and GM-CSF mRNAs as well as IL-8 mRNA. ARPE-19 cells showed similar increases in the same cytokines. Interestingly, the kinetics of expression of the various cytokines differed. These results provide further evidence that C5a stimulation of RPE cells may play a role in regulating leucocyte function during ocular inflammation in which there is complement activation.


Assuntos
Complemento C5a/imunologia , Citocinas/biossíntese , Epitélio Pigmentado Ocular/imunologia , Antígenos CD/metabolismo , Linhagem Celular , Citocinas/genética , Expressão Gênica , Humanos , Interleucina-8/biossíntese , Interleucina-8/genética , RNA Mensageiro/genética , Receptor da Anafilatoxina C5a , Receptores de Complemento/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
9.
Med Biol Eng Comput ; 41(1): 94-100, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12572753

RESUMO

Total hip joint arthroplasty is commonly used in cases of osteoarthritis and rheumatoid arthritis. A hip joint prosthesis consists of a cup and a stem. The relative pose (position and orientation) of the prosthesis, when the patient is standing naturally, is planned pre-operatively; however, there is no guarantee that the pre-operatively planned pose will be accurate. Prosthesis component malposition, which is inadequate positioning of the acetabular or femoral component, results in limited joint movement and a large prosthetic joint contact area, and this can cause dislocation of the femoral head from the cap. Because the range of motion after total hip joint arthroplasty is determined by the relative pose of the cup and the stem, it is important to know the relative pose after hip arthroplasty. Several pose estimation methods using single-plane fluoroscopy or conventional roentgenography have been proposed. Because a conventional radiograph system is commonly used at small cost, a method using conventional radiograms is desirable for use in a clinical setting. In this study, a pose estimation method using conventional radiography is proposed, and an in vitro experiment is performed to evaluate its accuracy. The rotational errors of the relative pose of the cup with respect to the stem were smaller than 2.3 degrees.


Assuntos
Articulação do Quadril/diagnóstico por imagem , Prótese de Quadril , Articulação do Quadril/fisiologia , Humanos , Período Pós-Operatório , Radiografia , Amplitude de Movimento Articular
10.
Spinal Cord ; 40(12): 631-8, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12483496

RESUMO

STUDY DESIGN: Cross-sectional study comparing trained spinal cord injured (SCI) subjects (lesion level: L1 - T6) with healthy young subjects (CONT). OBJECTIVE: To investigate the kinetics of response in oxygen uptake (VO(2)) in human upper-body skeletal muscles, nine trained SCI subjects underwent submaximal supine arm exercises. METHOD: The SCI subjects underwent an incremental arm exercise test until exhaustion. The days after this first round of testing, breath-by-breath VO(2) and beat-by-beat heart rate (HR) on- and off-kinetics were determined during three repetitions of constant exercise at 50% of VO(2peak). The overall time course of response was determined from the half time (t(1/2)). Increased capillary blood lactate production (delta[La]b) at the onset of exercise was defined as the difference between at rest and at the end of exercise. Cardiac output (Q) was measured using the acetylene rebreathing method during the steady state of exercise. In accordance with the Fick principle, the difference in arterial-venous O(2) content (Ca-vO(2)) was defined as VO(2)/Q. RESULTS: During the steady state of the submaximal arm exercise, a more significant increase in the steady state of Q was obtained in the CONT subjects than in the trained SCI subjects: respectively, 14.9+/-1.4 l/min versus (12.7+/-0.8 l/min). There was no difference in the steady state of VO(2) between the two groups; as a result, SCI subjects had the greater Ca-v(2). Meanwhile, VO(2) on- and off-kinetics became much faster in the trained SCI subjects than in the CONT subjects. In addition, t(1/2) HR on-kinetics was not significantly different between the SCI and CONT groups. Increased Delta[La]b was closely related to larger t(1/2) VO(2) on-kinetics (r = 0.624, P < 0.05). CONCLUSION: It is concluded that the acceleration of VO(2) on- and off-kinetics in the trained SCI subjects was observed even though there was no difference in HR on- and off-kinetics between the SCI and CONT groups and a lower steady state of Q in the trained SCI subjects. VO(2) kinetics would therefore be the limiting factor in oxidative phosphorylation in the upper skeletal muscles, thereby providing a lower lactic O(2)-deficit (ie delta[La]b).


Assuntos
Exercício Físico , Oxigênio/análise , Traumatismos da Medula Espinal/fisiopatologia , Adulto , Braço/fisiologia , Dióxido de Carbono/análise , Débito Cardíaco/fisiologia , Estudos Transversais , Feminino , Frequência Cardíaca/fisiologia , Hemodinâmica/fisiologia , Humanos , Cinética , Ácido Láctico/sangue , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/fisiologia , Traumatismos da Medula Espinal/reabilitação
11.
Med Biol Eng Comput ; 40(1): 22-8, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11954704

RESUMO

The object of the study was to model fixed-bearing knee prostheses (FBKs) and mobile-bearing knee prostheses (MBKs) during weight-bearing deep knee bends and to analyse and compare the kinematics of the two prosthesis types. To obtain quantitative data, an overall model of a leg was constructed, and this included a three-dimensional model of the tibiofemoral joint and simplified two-dimensional models of the ankle and patellofemoral joint. The simulated movement pattern of the tibiofemoral contact point in the FBK was analysed to show the posterior contact position on the tibia at full extension and anterior translation as the knee was flexed from 30 degrees to 90 degrees. The simulated maximum displacements of the medial and lateral contact positions of the FBK were 5.6 and 6.2 mm, respectively. These results were almost in agreement with experimental studies. Compared with the FBK, the movement pattern of the tibiofemoral contact point in the MBK for the anterior contact position on the tibia at full extension and posterior translation, with respect to the tibia as the knee was flexed, gave results closer to those of the normal knee. The simulated displacements of the medial and lateral contact positions of the MBK with respect to the tibia were 9.0 and 13.0 mm from full extension to 90 degrees flexion, respectively. The difference in the kinematic results between the FBK and the MBK could be accounted for by movement of the insert and the larger force of the posterior cruciate ligament on the MBK.


Assuntos
Prótese do Joelho , Modelos Biológicos , Amplitude de Movimento Articular , Fenômenos Biomecânicos , Humanos , Suporte de Carga/fisiologia
12.
J Cardiol ; 38(5): 281-7, 2001 Nov.
Artigo em Japonês | MEDLINE | ID: mdl-11729728

RESUMO

A 51-year-old man presented under a diagnosis of angina pectoris manifesting as exertional chest pain. First coronary angiography showed severe stenosis with ulceration and spontaneous dissection at the proximal right coronary artery and linear dissection-like filling defects extending to the distal right coronary artery. After about 3 months, repeat coronary angiography showed the previously observed stenosis with unclear dissection, and better developed collaterals from the left coronary artery to the right coronary artery showing the linear dissection-like filling defects. The bilateral coronary angiography did not clearly show filling defects. This phenomenon suggested that the collateral flows were related to filling of the defects. Intravascular ultrasonic imaging demonstrated severe atherosclerotic lesions at the proximal right coronary artery, but no dissection in the distal right coronary artery. Percutaneous transluminal coronary angioplasty for the stenosis was performed successfully with a stent. Coronary angiography after the angioplasty showed no collaterals, and the right ventricular branch appeared, suggesting that the linear dissection-like filling defects extending to the distal right coronary artery were due to the collateral flows. Filling defects extending distal to a severe stenosis must be distinguished carefully from coronary dissection.


Assuntos
Angiografia Coronária , Doença das Coronárias/diagnóstico por imagem , Angioplastia Coronária com Balão , Circulação Colateral , Humanos , Masculino , Pessoa de Meia-Idade , Ultrassonografia
13.
Immunology ; 104(2): 215-25, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11683962

RESUMO

Decay-accelerating factor (DAF) is a membrane regulator of C3 activation that protects self cells from autologous complement attack. In humans, DAF is uniformly expressed as a glycosylphosphatidylinositol (GPI)-anchored molecule. In mice, both GPI-anchored and transmembrane-anchored DAF proteins are produced, each of which can be derived from two different genes (Daf1 and Daf2). In this report, we describe a Daf1 gene knock-out mouse arising as the first product of a strategy for targeting one or both Daf genes. As part of the work, we characterize recently described monoclonal antibodies against murine DAF protein using deletion mutants synthesized in yeast, and then employ the monoclonal antibodies in conjunction with wild-type and the Daf1 knock-out mice to determine the tissue distribution of the mouse Daf1 and Daf2 gene products. To enhance the immunohistochemical detection of murine DAF protein, we utilized the sensitive tyramide fluorescence method. In wild-type mice, we found strong DAF labelling of glomeruli, airway and gut epithelium, the spleen, vascular endothelium throughout all tissues, and seminiferous tubules of the testis. In Daf1 knock-out mice, DAF labelling was ablated in most tissues, but strong labelling of the testis and splenic dendritic cells remained. In both sites, reverse transcription-polymerase chain reaction analyses identified both GPI and transmembrane forms of Daf2 gene-derived protein. The results have relevance for studies of in vivo murine DAF function and of murine DAF structure.


Assuntos
Antígenos CD55/metabolismo , Proteínas de Saccharomyces cerevisiae , Animais , Anticorpos Monoclonais/imunologia , Sítios de Ligação/imunologia , Antígenos CD55/genética , Antígenos CD55/imunologia , Proteínas de Caenorhabditis elegans , Complemento C3/análise , Ciclinas/genética , Proteínas Fúngicas/genética , Técnicas Imunoenzimáticas , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptor de Insulina/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Distribuição Tecidual
14.
Acta Neuropathol ; 102(1): 89-93, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11547956

RESUMO

Respiratory insufficiency has been reported frequently in patients with myotonic dystrophy (MyD). Recent data support the hypothesis that this respiratory failure results from a primary dysfunction of the central nervous system. The medullary arcuate nucleus (ARC) has been shown to be involved in the regulation of respiration. We performed a quantitative study of neurons in the ARC in eight MyD patients, ten control subjects with other neurological diseases (control group A) and eight control subjects without neurological diseases (control group B). Alveolar hypoventilation of the central type occurred in three of the MyD patients but not in the remaining MyD patients or controls. The density of neurons in the ARC in MyD patients with hypoventilation was significantly lower than in MyD patients without hypoventilation and control groups A and B. There was no significant difference in the neuronal density of the ARC between MyD patients without hypoventilation and control groups A and B. These data suggest that the neuronal loss of the ARC is associated with the presence of hypoventilation in MyD.


Assuntos
Núcleo Arqueado do Hipotálamo/patologia , Distrofia Miotônica/patologia , Neurônios/patologia , Idoso , Contagem de Células , Feminino , Humanos , Hipoventilação/etiologia , Masculino , Bulbo , Pessoa de Meia-Idade , Distrofia Miotônica/complicações , Valores de Referência
15.
J Cell Biochem ; 82(2): 234-45, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11527149

RESUMO

Isolated glycosylphosphatidylinositol (GPI)-anchored proteins, when added to cells in vitro, incorporate into their surface membranes and, once incorporated, exert their native functions. Virtually any protein of interest, if expressed as a GPI-reanchored derivative, can be modified to acquire this capacity. Such transfer of proteins directly to cells, termed "protein engineering" or "painting" constitutes an alternative to conventional gene transfer for manipulating cell surface composition that has many potential applications. Previous studies with incorporated GPI-anchored proteins have focused almost entirely on their extracellular functions. In this study, biotinylated human erythrocyte (E(hu)) decay accelerating factor, E(hu) acetylcholinesterase, and GPI-reanchored murine B7-1 and B7-2 were used as GPI-anchored reporters to characterize their plasma membrane organization and cell signalling properties following addition to Hela or Chinese hamster ovary cells. For each reporter, three types of cell-association were documented; (1) nonphysiological attachment and/or incomplete insertion, (2) uncomplexed membrane integration, and (3) organization into TX-100-resistant microdomains. Transit from the first two compartments into the third, i.e., microdomains, progressed slowly, continuing even after 24 to 36 h and was associated with the acquisition of cell signalling capacity. All four reporters, incorporated in two different detergents, behaved similarly. When organized in microdomains, caveolin and other GPI proteins co-isolated with the incorporated reporter. These results have implications for protein engineering of cells in general, and in particular, for cells such as modified tumor cell immunogens administered to patients for therapeutic purposes.


Assuntos
Membrana Celular/metabolismo , Glicosilfosfatidilinositóis/farmacologia , Acetilcolinesterase/metabolismo , Animais , Antígenos CD/metabolismo , Antígeno B7-1/metabolismo , Antígeno B7-2 , Biotinilação , Antígenos CD55/metabolismo , Células CHO , Vacinas Anticâncer , Compartimento Celular , Centrifugação com Gradiente de Concentração , Cricetinae , Cricetulus , Eletroforese em Gel de Poliacrilamida , Glicosilfosfatidilinositóis/administração & dosagem , Glicosilfosfatidilinositóis/metabolismo , Células HeLa , Humanos , Glicoproteínas de Membrana/metabolismo , Microdomínios da Membrana/metabolismo , Camundongos , Fosforilação , Engenharia de Proteínas , Processamento de Proteína Pós-Traducional , Proteínas Recombinantes de Fusão/metabolismo , Fatores de Tempo , Transfecção
16.
IEEE Trans Neural Syst Rehabil Eng ; 9(2): 145-53, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11474967

RESUMO

In the present study, the function of the somatosensory feedback system in postural control was investigated. For the sake of simplicity, the present study considered only balancing in the anteroposterior direction using the ankle strategy, in which the ankle moment is mainly used to maintain balance. To suppress the vestibular and visual feedback paths, a subject stood on a force-measuring platform with a fixed back support. Because the subject's body was immovable under these conditions, the subject controlled a computer model that simulated the subject's load at the ankles. Information about the sway angle of the model was fed through the somatosensory feedback path. Frequency response functions of the ankle moment in response to the sway angle were calculated. The experimental results suggest that the human somatosensory feedback system has derivative characteristics and, consequently, can maintain an upright posture by itself. The results were compared with those of previous studies on vestibular and visual feedback systems. The comparison reveals that subject-to-subject variance in the somatosensory system is significantly smaller than that in the other systems. This may indicate that the somatosensory feedback is the most automatic of the systems and plays a dominant role when a subject maintains an upright posture using the ankle strategy.


Assuntos
Potenciais Somatossensoriais Evocados/fisiologia , Retroalimentação , Equilíbrio Postural/fisiologia , Postura , Adulto , Tornozelo/fisiologia , Simulação por Computador , Humanos , Masculino , Pessoa de Meia-Idade , Suporte de Carga
17.
J Neurosci Nurs ; 33(3): 148-9, 155-9, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11413660

RESUMO

Both gastric and duodenal feeding tubes are used to provide enteral nutrition. Most studies comparing the two methods have focused primarily on rates of complications, rather than on nutritional outcomes, and show no difference in complications between the two methods. It is not clear which feeding route provides the best nutritional outcomes. The primary purpose of this randomized clinical pilot study was to compare the percentage of recommended calories and protein received by patients with neurological disease being fed enterally via gastric or duodenal feeding tubes. Secondary aims were to compare the following between groups: physiological effects of feeding, reasons for delay in feeding, volume of feeding residual, number of feeding tubes replaced, cost of feeding, and number and types of complications. A convenience sample of 25 neuro intensive care unit patients was randomly assigned to gastric or duodenal feeding. Enteral feeding was ordered by using a standardized prescription formula and provided by the nursing staff. Serum albumin and prealbumin levels were measured at baseline, day 3, and day 10. Nitrogen balance was measured on day 10. Enteral feeding data were collected daily. No significant differences were found between gastric and duodenal groups in nutritional outcomes, including percentage of recommended calories and protein received, physiological effects of feeding, reasons for delay in feeding, feeding residual, number of feeding tubes replaced, cost of feeding, and number and types of complications. Neither group achieved mean recommended caloric or protein intake during the 10 days of the study. Further research is needed to address how recommended nutrients can be provided enterally in a more timely and complete manner in critically ill NICU patients.


Assuntos
Doenças do Sistema Nervoso Central/enfermagem , Nutrição Enteral/enfermagem , Adulto , Idoso , Cuidados Críticos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação Nutricional , Projetos Piloto , Estudos Prospectivos , Resultado do Tratamento
18.
Jpn J Ophthalmol ; 45(1): 115-116, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11341903

RESUMO

Purpose: To evaluate the association between the vitreous and the refractive error in pseudophakia.Methods: Vitrectomy was performed in 67 eyes of 61 patients who underwent cataract surgery. Vitrectomy was needed for epiretinal membrane in 30 eyes, macular edema in 22 eyes, macular hole in 3 eyes, lamelar macular hole in 2 eyes, macular hole in 3 eyes, lamelar macular hole in 2 eyes, vitreous opacity in 6 eyes, and vitreous hemorrhage in 4 eyes. Refraction was measured before the operation, and 1 month, 3 months, 6 months, and 12 months after operation. Anterior chamber depth was measured in 10 eyes before the operation, and 1 month, 3 months, and 6 months after operation. We evaluated the refractive error after vitrectomy in 49 eyes that had predicted refraction.Results: The mean value of refractive change was -0.3 D 1 month postoperatively, and then gradually became positive. The variation of refraction (6-month postoperative refraction minus preoperative refraction) was negatively correlated with preoperative refraction (P =.0052, R(2) = 0.146). If preoperative refraction was more myopic than -1.5 D, then refraction became positive. If preoperative refraction was not more myopic than -1.5 D, then refraction became negative.Conclusion: About 15% of postoperative refractive error may be associated with the vitreous, but further investigation is required.

19.
Artigo em Inglês | MEDLINE | ID: mdl-11244370

RESUMO

We report a rare case of incus dislocation to the external auditory canal after a mountain-biking accident. Otoscopy showed ossicular protrusion in the upper part of the left external auditory canal. CT indicated the disappearance of the incus, and an incus-like bone was found in the left external auditory canal. There was another bony and board-like structure in the attic. During the surgery, a square-shaped bony plate (1 x 1 cm) was found in the attic. It was determined that the bony plate had fallen from the tegmen of the attic. The fracture line in the posterosuperior auditory canal extending to the fossa incudis was identified. According to these findings, it was considered that the incus was pushed into the external auditory canal by the impact of skull injury through the fractured posterosuperior auditory canal, which opened widely enough for incus dislocation.


Assuntos
Ciclismo/lesões , Bigorna/lesões , Luxações Articulares/etiologia , Adulto , Meato Acústico Externo , Feminino , Humanos , Bigorna/diagnóstico por imagem , Bigorna/cirurgia , Luxações Articulares/diagnóstico por imagem , Luxações Articulares/cirurgia , Procedimentos de Cirurgia Plástica , Fraturas Cranianas/etiologia , Tomografia Computadorizada por Raios X
20.
Immunol Lett ; 75(3): 167-77, 2001 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-11166372

RESUMO

A human monoclonal antibody (HuMab) TONO-1 (IgM, lambda) recognizes cell surface antigens associated primarily with human T-leukemia/lymphoma cells. In this study, we investigated the reactivity against T-leukemia/lymphoma cells in detail, cytotoxic potential and primary nucleotide and deduced amino acid sequences of the rearranged heavy and light chains of the HuMab TONO-1. Expression of the molecules (TONO-1 Ags) detected by a HuMab TONO-1 was significantly heterogeneous even in the same T-leukemia/lymphoma cell lines HPB-MLT and MOLT-4F. The flow cytometric curves showed an unusual broad-based spread of fluorescence intensity. HuMab TONO-1 was shown to have the ability to kill the T-leukernia/lymphoma cells efficiently in the presence of rabbit complements. However, HuMab TONO-1 did not demonstrate significant antibody-dependent cellular cytotoxic activity. Furthermore, HuMab TONO-1 heavy and light chain variable regions were cloned, sequenced and analyzed. HuMab TONO-1 uses a V(H) gene member of the V(H)IV gene family V(H)71-4, and is productively rearranged with the germ line D(H) gene D(XP')1, and the germ line J(H)5 gene with multiple somatic mutations. HuMab TONO-1 Vlambda belongs to the lambda light chain variable subgroup I family and is derived from the Vlambdalc germ line gene Humlv1042, and germ line gene Jlambda1 without somatic mutations. The results reveal that the production of HuMab TONO-1, with cytotoxic potential for human T-leukemia/lymphoma cells, is achieved by rearrangement of the V(H)71-4/Humlv1042 germ line variable region gene combination, that is associated with the autoimmune repertoire.


Assuntos
Anticorpos Monoclonais/química , Anticorpos Monoclonais/imunologia , Citotoxicidade Imunológica , Leucemia de Células T/imunologia , Linfoma de Células T/imunologia , Sequência de Aminoácidos , Anticorpos Monoclonais/genética , Anticorpos Monoclonais Humanizados , Citotoxicidade Celular Dependente de Anticorpos , Sequência de Bases , Citometria de Fluxo , Rearranjo Gênico , Genes de Imunoglobulinas , Humanos , Cadeias Pesadas de Imunoglobulinas/genética , Cadeias Leves de Imunoglobulina/genética , Região Variável de Imunoglobulina/genética , Dados de Sequência Molecular , Análise de Sequência de DNA , Células Tumorais Cultivadas
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