Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 47
Filtrar
1.
Chaos ; 33(7)2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37486665

RESUMO

Mobile intrinsic localized modes (ILMs) in balanced nonlinear capacitive-inductive cyclic transmission lines are studied by experiment, using a spatiotemporal driver under damped steady-state conditions. Without nonlinear balance, the experimentally observed resonance between the traveling ILM and normal modes of the nonlinear transmission line generates lattice drag via the production of a lattice backwave. In our experimental study of a balanced running ILM in a steady state, it is observed that the fundamental resonance can be removed over extended, well-defined driving frequency intervals and strongly suppressed over the complete ILM driving frequency range. Because both of these nonlinear capacitive and inductive elements display hysteresis our observation demonstrates that the experimental system, which is only partially self-dual, is surprisingly tolerant, regarding the precision necessary to eliminate the ILM backwave. It appears that simply balancing the cell dual nonlinearities makes the ILM envelope shape essentially the same at the two locations in the cell, so that the effective lattice discreteness seen by the ILM nearly vanishes.

2.
Phys Rev E ; 107(3-1): 034202, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37072939

RESUMO

A well-known feature of a propagating localized excitation in a discrete lattice is the generation of a backwave in the extended normal mode spectrum. To quantify the parameter-dependent amplitude of such a backwave, the properties of a running intrinsic localized mode (ILM) in electric, cyclic, dissipative, nonlinear 1D transmission lines, containing balanced nonlinear capacitive and inductive terms, are studied via simulations. Both balanced and unbalanced damping and driving conditions are treated. The introduction of a unit cell duplex driver, with a voltage source driving the nonlinear capacitor and a synchronized current source, the nonlinear inductor, provides an opportunity to design a cyclic, dissipative self-dual nonlinear transmission line. When the self-dual conditions are satisfied, the dynamical voltage and current equations of motion within a cell become the same, the strength of the fundamental, resonant coupling between the ILM and the lattice modes collapses, and the associated fundamental backwave is no longer observed.

3.
Chaos ; 32(3): 033118, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35364854

RESUMO

In this experimental study of the nonlinear loss mechanism between traveling localized excitation and the underlying extended normal mode spectrum for a 1D lattice, three types of cyclic, electric, nonlinear transmission lines (NLTLs) are used. They are nonlinear capacitive, inductive, and capacitive+inductive NLTLs. To maintain a robust, steady-state traveling intrinsic localized mode (ILM), a traveling wave driver is used. The ILM loses energy because of a resonance between it and the extended NLTL modes. A wake field excitation is detected directly from ILM velocity experiments by the decrease in ILM speed and by the observation of the wake. Its properties are quantified via a two-dimensional Fourier map in the frequency-wavenumber domain, determined from the measured spatial-time voltage pattern. Simulations support and extend these experimental findings. We find for the capacitive+inductive NLTL configuration, when the two nonlinear terms are theoretically balanced, the wake excitation is calculated to become very small, giving rise to supertransmission over an extended driving frequency range.

4.
Chaos ; 25(10): 103122, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26520088

RESUMO

It is well known that a moving intrinsic localized mode (ILM) in a nonlinear physical lattice looses energy because of the resonance between it and the underlying small amplitude plane wave spectrum. By exploring the Fourier transform (FT) properties of the nonlinear force of a running ILM in a driven and damped 1D nonlinear lattice, as described by a 2D wavenumber and frequency map, we quantify the magnitude of the resonance where the small amplitude normal mode dispersion curve and the FT amplitude components of the ILM intersect. We show that for a traveling ILM characterized by a specific frequency and wavenumber, either inside or outside the plane wave spectrum, and for situations where both onsite and intersite nonlinearity occur, either of the hard or soft type, the strength of this resonance depends on the specific mix of the two nonlinearities. Examples are presented demonstrating that by engineering this mix the resonance can be greatly reduced. The end result is a supertransmission channel for either a driven or undriven ILM in a nonintegrable, nonlinear yet physical lattice.

5.
Eur J Vasc Endovasc Surg ; 49(5): 565-73, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25747344

RESUMO

OBJECTIVES: Acceptable limb salvage rates underlie the widespread use of endovascular therapy (EVT) for patients with critical limb ischemia (CLI) secondary to isolated infrapopliteal lesions; however, post-EVT delayed wound healing remains a challenge. Predictors of delayed wound healing and their use in risk stratification of EVT in patients with CLI due to isolated infrapopliteal lesions are explored. METHODS: This was a retrospective multicenter study. 871 consecutive critically ischemic limbs were studied. There was tissue loss in 734 patients (age: 71 ± 10 years old; 71% male) who had undergone EVT between April 2004 and December 2012. The wound healing rate after EVT was estimated by the Kaplan-Meier method. The association between baseline characteristics and delayed wound healing was assessed by the Cox proportional hazard model. RESULTS: Diabetes mellitus and regular dialysis were present in 75% (553/734) and 64% (476/734) of patients, respectively; 67% of limbs (585/871) had Rutherford class 5 CLI; 8% (67/871) of wounds were located in the heel only; 25% (219/871) of limbs had Rutherford 6 (involving not only the heel); and 42% (354/871) of wounds were complicated by infection. The rate of freedom from major amputation at 1 year reached 88%, whereas the wound healing rate was 67%. Median time to wound healing was 146 days. By multivariate analysis, non-ambulatory status (hazard ratio [HR], 1.58; 95% confidence interval [CI] 1.31-1.91) serum albumin <3 g/dL (HR 1.42; 95% CI 1.08-1.86), Rutherford 6 (not only heel) (HR 1.68; 95% CI 1.33-2.14), wound infection (HR 1.24; 95% CI 1.03-1.50), EVT not based on angiosome concept (HR 1.28; 95% CI 1.06-1.55), and below the ankle (BTA) 0 vessel runoff after EVT (HR 1.45; 95% CI 1.14-1.86) were independent predictors of delayed wound healing. CONCLUSIONS: Non-ambulatory status, low albumin level, Rutherford 6 (not only heel), wound infection, indirect intervention, and poor BTA runoff were independent predictors for delayed wound healing after EVT in patients with CLI secondary to infrapopliteal lesions, and their use in risk stratification allows estimation of the wound healing rate.


Assuntos
Diabetes Mellitus/epidemiologia , Isquemia/epidemiologia , Salvamento de Membro , Extremidade Inferior/cirurgia , Diálise Renal/estatística & dados numéricos , Cicatrização , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Isquemia/cirurgia , Salvamento de Membro/métodos , Extremidade Inferior/irrigação sanguínea , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento , Cicatrização/fisiologia
6.
Chaos ; 25(1): 013103, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25637914

RESUMO

Both low frequency and high frequency impurity modes have been produced in a SiN micromechanical cantilever array by illumination with either an infrared or visible laser. When such laser-induced impurities are placed near a driven intrinsic localized mode (ILM), it is either repelled or attracted. By measuring the linear response spectrum for these two cases, it was found that vibrational hopping of the ILM takes place when the natural frequency of the ILM and an intrinsic even symmetry linear local mode are symmetrically located about the driven ILM frequency so that parametric excitation of these two linear modes is enhanced, amplifying the lateral motion of the ILM. Numerical simulations are consistent with these signature findings. It is also demonstrated that the correct sign of the observed interaction can be found with a harmonic lattice-impurity model but the magnitude of the effect is enhanced in a nonlinear lattice.

7.
Animal ; 9(4): 682-90, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25440615

RESUMO

A feeding station is the area of forage a grazing animal can reach without moving its forefeet. Grazing behavior can be divided into residence within feeding stations (with bites as benefits) and movement between feeding stations (with steps as costs). However, relatively little information has been reported on how grazing animals modify their feeding station behavior seasonally and interannually in response to varying environmental conditions. The feeding station behavior of beef cows (Japanese Black) stocked on a tropical grass pasture (bahiagrass dominant) was monitored for 4 years (2010 to 2013) in order to investigate the association of feeding station behavior with meteorological and sward conditions across the seasons and years. Mean air temperature during stocking often exceeded 30°C during summer months. A severe summer drought in 2013 decreased herbage mass and sward height of the pasture and increased nitrogen concentration of herbage from summer to autumn. A markedly high feeding station number per unit foraging time, low bite numbers per feeding station and a low bite rate were observed in summer 2013 compared with the other seasons and years. Bite number per feeding station was explained by a multiple regression equation, where sward height and dry matter digestibility of herbage had a positive effect, whereas air temperature during stocking had a negative effect (R 2=0.658, P<0.01). Feeding station number per minute was negatively correlated with bite number per feeding station (r=-0.838, P<0.001). It was interpreted that cows modified bite number per feeding station in response to the sward and meteorological conditions, and this largely determined the number of feeding stations the animals visited per minute. The results indicate potential value of bite number per feeding station as an indicator of daily intake in grazing animals, and an opportunity for livestock and pasture managers to control feeding station behavior of animals through managements (e.g. fertilizer application, manipulation of stocking intensity and stocking time within the day).


Assuntos
Bovinos/fisiologia , Herbivoria/fisiologia , Estações do Ano , Tempo (Meteorologia) , Ração Animal , Animais , Feminino , Poaceae , Fatores de Tempo
8.
Eur J Vasc Endovasc Surg ; 49(3): 297-305, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25524520

RESUMO

OBJECTIVE: To investigate the relationship between body mass index (BMI) and long-term outcomes of patients with CLI after endovascular treatment (EVT). DESIGN: Retrospective multicenter study. SUBJECTS: 1088 consecutive patients (1306 limbs, mean age 72 ± 10 years) with CLI who underwent EVT for isolated infrapopliteal artery lesions were evaluated. These subjects were identified in the J-BEAT III registry. METHODS: The patients were divided into groups based on BMI <18.5 kg/m2 (underweight, n = 188; 219 limbs), 18.5 to 24.9 kg/m2 (normal weight, n = 718; 868 limbs), and >25.0 kg/m2 (overweight/obese, n = 182; 219 limbs). The endpoints were overall survival and freedom from major adverse limb events (MALE). RESULTS: The median follow up period was 1.5 years (range: 1 month-8.7 years). The 3 year overall survival rates were 33.3%, 61.2%, and 69.8% in underweight, normal, and overweight/obese patients, respectively. The survival rate was significantly lower in underweight patients and significantly higher in overweight/obese patients compared with patients of normal weight (both p < .0001). The 3 year rates of freedom from MALE did not differ significantly among the three groups (36.4%, 45.4%, and 52.3%, respectively, p = .32). Age, BMI <18.5 kg/m2, heart failure, aortic valve stenosis, renal failure, triglyceride levels, serum albumin <3.0 g/dL, anticoagulant treatment, non-ambulatory status, and Rutherford 6 classification all were significantly associated with overall survival. CONCLUSIONS: BMI has a complex correlation with mortality in patients with CLI after EVT for isolated infrapopliteal artery lesions. Underweight patients with CLI have an extremely poor prognosis. Such patients have many other factors associated with mortality, but low BMI was identified as an independent predictor of a poor prognosis in patients with CLI. Similarly, normal weight patients had a small but significant increase in mortality compared with overweight/obese patients.


Assuntos
Índice de Massa Corporal , Procedimentos Endovasculares/mortalidade , Isquemia/cirurgia , Extremidade Inferior/irrigação sanguínea , Obesidade/mortalidade , Doença Arterial Periférica/cirurgia , Artéria Poplítea/cirurgia , Magreza/mortalidade , Idoso , Idoso de 80 Anos ou mais , Distribuição de Qui-Quadrado , Estado Terminal , Intervalo Livre de Doença , Procedimentos Endovasculares/efeitos adversos , Feminino , Humanos , Isquemia/diagnóstico , Isquemia/mortalidade , Japão , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Obesidade/complicações , Obesidade/diagnóstico , Doença Arterial Periférica/diagnóstico , Doença Arterial Periférica/mortalidade , Modelos de Riscos Proporcionais , Fatores de Proteção , Sistema de Registros , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Magreza/complicações , Magreza/diagnóstico , Fatores de Tempo , Resultado do Tratamento
9.
Eur J Vasc Endovasc Surg ; 47(2): 131-8, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24611185

RESUMO

OBJECTIVES: To investigate factors associated with 30-day perioperative complications (POC) after aorto-iliac (AI) stenting, and to compare follow-up cardiovascular prognosis between patients with and without POC. MATERIALS AND METHODS: This was a retrospective multicenter study. We used a multicenter database of 2012 consecutive patients who successfully underwent AI stenting for peripheral arterial disease in 18 centers in Japan from January 2005 to December 2009 to analyze independent predictors of POC and impact of POC on prognosis by logistic regression and a Cox proportional hazard regression model, respectively. RESULTS: Mean age was 71 ± 9 years (median: 72 years; range: 37-98 years), and 1,636 patients (81%) were men. POC occurred in 126 patients (6.3%). In multivariate logistic regression analysis, old age (≥80 years), critical limb ischemia (CLI), and Trans Atlantic Inter-Societal Consensus (TASC) II class C/D were independently associated with POC with adjusted odds ratios and 95% confidence intervals (CI) of 1.9 (1.3-2.9), 2.3 (1.5-3.4), and 2.4 (1.6-3.4), respectively. Out of 2012 patients, 1995 were followed up for more than 30 days (mean: 2.6 ± 1.5 years; range: 2-2,393 days). In a Cox hazard regression model adjusted for baseline clinical characteristics, POC was positively and independently associated with follow-up major adverse cardiac events (adjusted hazard ratio [HR]: 1.9; 95% CI: 1.3-2.8; p = .002), but not with major adverse limb events and target lesion revascularization (adjusted HR: 1.4; 95% CI: 0.7-2.7; p = .25; and adjusted HR: 1.2; 95% CI 0.6-2.6; p = .568), respectively. CONCLUSIONS: Age >80 years, CLI, and TASC C/D lesion were positively associated with POC after AI stenting. Occurrence of POC appears to adversely affect follow-up cardiovascular, but not limb and vessel prognosis.


Assuntos
Angioplastia com Balão/efeitos adversos , Angioplastia com Balão/instrumentação , Doenças da Aorta/terapia , Artéria Ilíaca , Isquemia/terapia , Doença Arterial Periférica/terapia , Stents , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Doenças da Aorta/diagnóstico , Constrição Patológica , Estado Terminal , Feminino , Humanos , Artéria Ilíaca/diagnóstico por imagem , Isquemia/diagnóstico , Japão , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Doença Arterial Periférica/diagnóstico , Modelos de Riscos Proporcionais , Radiografia , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
10.
Eur J Vasc Endovasc Surg ; 46(5): 575-82, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24034905

RESUMO

OBJECTIVES: To investigate factors in patients with critical limb ischemia (CLI) and isolated infrapopliteal lesions that adversely affect outcomes of endovascular therapy (EVT) with or without angiosome-oriented revascularization. METHODS: This was a retrospective multicenter study. We used a database of 718 consecutive CLI patients (70 ± 11 years, 75% diabetics, 68% on hemodialysis, 24% Rutherford class 6) with ischemic tissue loss due to isolated infrapopliteal lesions undergoing primary EVT. Primary outcome was MALE (major adverse limb event). Association between indirect EVT (recanalization of a non-angiosome-based artery) and outcome was assessed by Cox proportional hazard regression model. RESULTS: C-reactive protein (CRP) level was >3 mg/dL in 32% of cases. Indirect EVT (in 307 CLI patients, 43%), was associated with MALE (p = .04, hazard ratio [95% confidence interval] 1.25 [1.01, 1.55]), and interacted with CRP >3 mg/dL (p < .004) but not with other baseline characteristics. Indirect EVT with CRP >3 mg/dL had higher MALE risk (HR 2.08), and interacted with diabetes mellitus (DM) presence. Indirect EVT with CRP >3 mg/dL and DM had higher MALE risk (HR 2.17). CONCLUSION: Limb prognosis was equivalent for direct and indirect endovascular revascularization except in the presence of both diabetes and wound infection, when indirect revascularization has a poorer outcome.


Assuntos
Angiopatias Diabéticas/cirurgia , Procedimentos Endovasculares/efeitos adversos , Isquemia/cirurgia , Infecção dos Ferimentos/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Proteína C-Reativa/análise , Estado Terminal , Angiopatias Diabéticas/sangue , Angiopatias Diabéticas/diagnóstico , Angiopatias Diabéticas/epidemiologia , Nefropatias Diabéticas/epidemiologia , Nefropatias Diabéticas/terapia , Feminino , Humanos , Isquemia/sangue , Isquemia/diagnóstico , Isquemia/epidemiologia , Japão/epidemiologia , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Prevalência , Modelos de Riscos Proporcionais , Diálise Renal , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Infecção dos Ferimentos/sangue , Infecção dos Ferimentos/diagnóstico
11.
Eur J Vasc Endovasc Surg ; 44(6): 577-81, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23107298

RESUMO

OBJECTIVE: To investigate whether cilostazol reduces restenosis and revascularization after infrapopliteal angioplasty. DESIGN: This study was a retrospective analysis of a multicenter prospective registry. MATERIALS AND METHODS: Between February and April 2011, 63 patients (68 limbs, 101 lesions) with critical limb ischemia (CLI) were enrolled. Of these, 32 were cilostazol treated and 31 were the non-cilostazol-treated group. Outcome measures were binary restenosis by angiogram, reocclusion, target lesion revascularization (TLR), limb salvage rate and complete wound healing at 3 months. RESULT: Procedural success was obtained in all patients. The backgrounds and lesion characteristics of patients with isolated tibial artery disease and CLI did not differ significantly between the two groups. In a lesion-based analysis, binary restenosis and reocclusion were significantly lower in the cilostazol group than in the non-cilostazol group (56.8% vs. 86.0%; p = 0.015, 20.5% vs. 43.6%; p = 0.015, respectively). The TLR was also significantly lower in the cilostazol group (27.5% vs. 52.8%, p = 0.014). After adjustment for covariables, cilostazol was found to be associated with reduced angiographic restenosis, reocclusion and TLR rates in CLI patients at 3 months after infrapopliteal angioplasty. However, it remained unclear whether cilostazol was also associated with improved clinical outcomes. CONCLUSION: Cilostazol may be associated with reduced restenosis, reocclusion and clinically driven TLR at 3 months after infrapopliteal angioplasty.


Assuntos
Angioplastia com Balão , Fármacos Cardiovasculares/uso terapêutico , Isquemia/terapia , Doença Arterial Periférica/terapia , Artéria Poplítea/efeitos dos fármacos , Tetrazóis/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Angioplastia com Balão/efeitos adversos , Angioplastia com Balão/mortalidade , Distribuição de Qui-Quadrado , Cilostazol , Constrição Patológica , Feminino , Humanos , Isquemia/diagnóstico por imagem , Isquemia/tratamento farmacológico , Isquemia/mortalidade , Japão , Salvamento de Membro , Modelos Logísticos , Masculino , Doença Arterial Periférica/diagnóstico por imagem , Doença Arterial Periférica/tratamento farmacológico , Doença Arterial Periférica/mortalidade , Artéria Poplítea/diagnóstico por imagem , Radiografia , Sistema de Registros , Estudos Retrospectivos , Prevenção Secundária , Fatores de Tempo , Resultado do Tratamento , Cicatrização/efeitos dos fármacos
12.
Eur J Vasc Endovasc Surg ; 44(4): 425-31, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22938944

RESUMO

OBJECTIVE: To assess 3- and 12-month angiographic restenosis rates and their clinical impact after infrapopliteal angioplasty. DESIGN: Prospective multicenter study. MATERIALS AND METHODS: We analyzed 68 critical ischemic limbs (tissue loss: 58 limbs) from 63 consecutive patients due to isolated infrapopliteal lesions who underwent angioplasty alone. Primary endpoint was 3-month angiographic restenosis rate; secondary endpoints were 12-month angiographic restenosis rate, and 3- and 12-month rates of mortality, major amputation and reintervention. Three- and 12-month frequency of ambulatory status and of freedom from ischemic symptoms, and time to wound healing in the ischemic wound group, were compared between restenotic and non-restenotic groups. Angiographic restenosis predictors were assessed by multivariable analysis. RESULTS: 95% of cases had 3-month angiography; restenosis rate was 73%: 40% restenosis and 33% re-occlusion. Twelve-month follow-up angiography was conducted for the patients without 3-month angiographic restenosis, and restenosis rate at 12 months was 82%. Non-administration of cilostazol and statin, and chronic total occlusion were 3-month angiographic restenosis predictors. Three- and 12-month mortality was 5% and 12%, respectively. Despite no patients having undergone amputation, 15% had persistent ischemic symptoms, and 48% of limbs underwent reintervention within 12 months. During the same study period, ambulatory status and limbs with complete healing were more frequently observed in the non-restenosis group than in the restenosis group. In the tissue loss group, time to wound healing in the restenosis group was longer than in the non-restenosis group (127 days vs. 66 days, p = 0.02). CONCLUSION: The extremely high angiographic restenosis rate after infrapopliteal angioplasty may adversely impact clinical status improvement.


Assuntos
Angiografia , Angioplastia/métodos , Oclusão de Enxerto Vascular/diagnóstico por imagem , Artéria Poplítea/cirurgia , Idoso , Amputação Cirúrgica/estatística & dados numéricos , Feminino , Seguimentos , Oclusão de Enxerto Vascular/epidemiologia , Oclusão de Enxerto Vascular/cirurgia , Humanos , Incidência , Isquemia/diagnóstico por imagem , Isquemia/cirurgia , Japão/epidemiologia , Perna (Membro)/irrigação sanguínea , Masculino , Artéria Poplítea/diagnóstico por imagem , Prognóstico , Estudos Prospectivos , Falha de Prótese , Reoperação/estatística & dados numéricos , Taxa de Sobrevida , Fatores de Tempo
13.
Eur J Vasc Endovasc Surg ; 44(3): 318-24, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22682012

RESUMO

OBJECTIVE: To identify anatomical factors associated with major adverse limb events (MALE) after angioplasty as the basis for a novel morphology-driven classification of infrapopliteal lesions. DESIGN: Retrospective-multicenter study. MATERIALS AND METHODS: Between March 2004 and October 2010, 1057 limbs from 884 patients with CLI due to isolated infrapopliteal lesions were studied. Freedom-from MALE, defined as major amputation or any reintervention, was assessed out to 2 years by the Kaplan-Meier methods. Anatomical predictors and risk stratification for MALE were analyzed by multivariate analysis. RESULTS: Freedom-from MALE was 47 ± 1% at 2 years. Lesion calcification, target vessel diameter<3.0 mm, lesion length>300 mm and no below-the-ankle (BA) run-off were positively associated with MALE by multivariate-analysis. The total number of risk factors was used to calculate the risk score for each limbs for subsequent categorization into 3 groups with 0 or 1 (low-risk), 2 (moderate-risk) and 3 or 4 (high-risk) factors. Freedom-from MALE at 2 year-rates was 59% in low-risk, 46% in moderate-risk, and 29% in high-risk, respectively. CONCLUSION: Target vessel diameter <3.0 mm, lesion calcification, lesion length > 300 mm and no-BA run-off were associated with MALE after infrapopliteal angioplasty. Risk stratification based on these predictors allows estimation of future incidence of MALE in CLI with isolated infrapopliteal lesions.


Assuntos
Angioplastia com Balão/efeitos adversos , Arteriopatias Oclusivas/terapia , Isquemia/terapia , Artéria Poplítea , Calcificação Vascular/terapia , Idoso , Idoso de 80 Anos ou mais , Angiografia Digital , Índice Tornozelo-Braço , Arteriopatias Oclusivas/complicações , Arteriopatias Oclusivas/diagnóstico , Arteriopatias Oclusivas/fisiopatologia , Distribuição de Qui-Quadrado , Constrição Patológica , Estado Terminal , Feminino , Hemodinâmica , Humanos , Isquemia/diagnóstico , Isquemia/etiologia , Isquemia/fisiopatologia , Japão , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Artéria Poplítea/diagnóstico por imagem , Artéria Poplítea/fisiopatologia , Modelos de Riscos Proporcionais , Sistema de Registros , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Índice de Gravidade de Doença , Fatores de Tempo , Resultado do Tratamento , Ultrassonografia Doppler Dupla , Calcificação Vascular/complicações , Calcificação Vascular/diagnóstico , Calcificação Vascular/fisiopatologia
14.
Clin Res Hepatol Gastroenterol ; 36(3): e43-7, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22239827

RESUMO

A lesion was discovered in the tail of the pancreas by ultrasonography performed during a health checkup for a 59-year-old Japanese man. Abdominal contrast-enhanced computed tomography (CE-CT) revealed strong enhancement in a 4-cm tumor in the pancreatic tail and in a 1-cm tumor in the pancreatic body. Serum glucagon levels were elevated to 54,405 pg/mL and a preoperative diagnosis of glucagonoma was made. The pancreatic tail and spleen were resected en bloc, along with a protruding tumor in the pancreatic body. However, histopathological evaluation revealed diffuse glucagonoma throughout the pancreas. When we retrospectively reviewed abdominal CE-CT after the operation, the entire pancreas was seen to be enlarged and diffusely enhanced by strong spots. Immunohistochemical examination using anti-CD31 demonstrated rich microvessels in two solid glucagonomas as well as microglucagonoma throughout the entire pancreas, indicating hypervascularity. Enlarged pancreas and diffuse enhancement of the pancreas by strong spots may be characteristic features of diffuse glucagonoma on abdominal CE-CT.


Assuntos
Glucagonoma/diagnóstico por imagem , Neoplasias Pancreáticas/diagnóstico por imagem , Fluordesoxiglucose F18 , Glucagon/sangue , Glucagonoma/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/cirurgia , Compostos Radiofarmacêuticos , Tomografia Computadorizada por Raios X
15.
Eur J Vasc Endovasc Surg ; 43(3): 313-21, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22240338

RESUMO

OBJECTIVES: To assess and risk stratify midterm clinical outcomes after endovascular therapy (EVT) by angioplasty only of patients with critical limb ischaemia (CLI) due to isolated below-the-knee (BTK) lesions. DESIGN: Retrospective multicenter study. MATERIALS AND METHODS: Between March 2004 and October 2010, 465 limbs (Rutherford 5 and 6: 79%) from 406 patients were studied. Overall survival, limb salvage, and re-intervention were examined out to 3 years by the Kaplan-Meier method and the log-rank test. Their independent predictors and risk stratification were analysed. RESULTS: Patient age was 71 ± 11 yrs, with 69% diabetics and 60% on dialysis. Mean follow-up was 18 ± 15 months. Overall survival was 76 ± 2 and 57 ± 4% at 1 and 3, years, respectively. Survival predictors were body mass index <18, non-ambulatory status and ejection fraction <45%. Two-year limb salvage rate was 80 ± 2%. Factors associated with major amputation were ulcers (Rutherford 6), diabetes mellitus, C-reactive protein>5 mg/dL, and age < 60 years. Two-year freedom from re-intervention was 66 ± 3%; age and below-the-ankle runoff number after angioplasty was negatively associated with re-intervention. CONCLUSIONS: Despite relatively high mortality and re-intervention rates, limb salvage rate was acceptable after EVT for CLI patients with isolated BTK lesions. Risk stratification allows occurrence estimation for each end point.


Assuntos
Angioplastia com Balão , Isquemia/cirurgia , Perna (Membro)/irrigação sanguínea , Perna (Membro)/cirurgia , Salvamento de Membro/métodos , Salvamento de Membro/estatística & dados numéricos , Idoso , Amputação Cirúrgica , Doenças Cardiovasculares/epidemiologia , Causas de Morte , Comorbidade , Diabetes Mellitus/epidemiologia , Dislipidemias/epidemiologia , Feminino , Seguimentos , Humanos , Hipertensão/epidemiologia , Isquemia/mortalidade , Falência Renal Crônica/epidemiologia , Masculino , Pessoa de Meia-Idade , Reoperação , Estudos Retrospectivos , Fatores de Risco , Fumar/epidemiologia , Taxa de Sobrevida , Resultado do Tratamento
16.
Int J Dent Hyg ; 9(2): 159-62, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21356008

RESUMO

OBJECTIVES: Oral health care providers may discover systemic diseases incidentally from signs observed in the oral cavity. Here, we report a case in which oral health care providers in a hospital discovered a patient with strongly suspected bullous pemphigoid (BP), which is a relatively rare but important disease, in a ward. METHODS: The patient was a 78-year-old Japanese woman admitted to our hospital because of severe Alzheimer's disease. We discovered recurrent ulcers in the oral mucosa and skin when performing oral care in her ward. Biopsy could not be performed safely because of involuntary biting. We performed blood tests for anti-BP180-NC16a antibody, which is autoantibody specific for BP. RESULTS: The patient had a very high anti-BP180-NC16a antibody titre. We consulted a dermatologist regarding her clinical course and the clinical features of the oral mucosa and skin along with blood test results. BP was very strongly suspected. DISCUSSION: In cases in which oral health care providers suspect their patients may have BP, appropriate examination and provision of information to the doctor are important. Oral health care providers should have knowledge about systemic diseases, the signs of which appear in oral cavity to avoid missing important systemic diseases.


Assuntos
Doença de Alzheimer/complicações , Autoanticorpos/sangue , Assistência Odontológica para Doentes Crônicos , Penfigoide Bolhoso/diagnóstico , Idoso , Autoantígenos/sangue , Autoantígenos/imunologia , Feminino , Humanos , Achados Incidentais , Pacientes Internados , Colágenos não Fibrilares/sangue , Colágenos não Fibrilares/imunologia , Penfigoide Bolhoso/sangue , Penfigoide Bolhoso/complicações , Colágeno Tipo XVII
17.
J Chemother ; 22(2): 98-102, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20435568

RESUMO

Although meropenem is commonly used for intra-abdominal infections, its penetration into the abdominal cavity is not well understood. Meropenem (500 mg) was administered intravenously to 8 patients with inflammatory bowel diseases undergoing laparotomy. The drug concentrations were analyzed and used for a Monte Carlo simulation with minimum inhibitory concentration (MIC) data. Meropenem concentrations in peritoneal fluid (PF) and plasma were similar at 1 h after the end of a 0.5-h infusion. The probabilities of target achievement of drug concentrations over the MIC in PF for 40% of the dosing interval with 500 mg every 8 h and 1000 mg every 8 h, were 84% and 90% against Bacteroides spp., 98% and 99% against Escherichia coli , and 76% and 83% against Pseudomonas aeruginosa, respectively. In conclusion, meropenem penetrated PF well, and 500 mg every 8 h or 1000 mg every 8 h would be suitable for the therapy for intraabdominal infections.


Assuntos
Antibacterianos/farmacologia , Líquido Ascítico/microbiologia , Bactérias Gram-Negativas/efeitos dos fármacos , Doenças Inflamatórias Intestinais/cirurgia , Tienamicinas/farmacologia , Adulto , Antibacterianos/farmacocinética , Área Sob a Curva , Feminino , Humanos , Doenças Inflamatórias Intestinais/microbiologia , Masculino , Meropeném , Taxa de Depuração Metabólica , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Método de Monte Carlo , Tienamicinas/farmacocinética
18.
Mol Oral Microbiol ; 25(2): 112-22, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20331799

RESUMO

Methanobrevibacter oralis is an archaeal species frequently isolated from sites of severe periodontitis. However, its pathogenic roles remain unclear. Here, we aimed to isolate group II chaperonin from M. oralis and examine its antigenicity. The genes encoding two chaperonin subunits (Cpn-1 and Cpn-2) were cloned from M. oralis using polymerase chain reaction and genome walking procedures. Recombinant proteins Cpn-1 and Cpn-2 were generated, and the reactivities of sera from patients with periodontitis were examined by Western immunoblotting. The open reading frames of Cpn-1 and Cpn-2 genes consisted of 1641 and 1614 base pairs, respectively. Putative ATP-binding domains conserved among the chaperonin family were observed in both genes. The deduced amino acid sequences of the two genes showed 28.8-40.0% identity to each of the subunits of human CCT (CCT1-8). Thirty and 29 of 36 patients' sera reacted with the recombinant Cpn-1 and recombinant Cpn-2, respectively. Western immunoblotting using antiserum against human CCT subunits indicated that anti-CCT3 and anti-CCT8 antibodies recognized recombinant Cpn-1. In addition, anti-CCT1, CCT3, CCT6, and CCT8 antibodies recognized an antigen of approximately 60 kDa in M. oralis. The results suggested that the chaperonin subunits of M. oralis were antigenic molecules that were recognized by periodontitis patients and that may cross-react with human chaperonin CCT.


Assuntos
Antígenos Arqueais/imunologia , Chaperoninas do Grupo II/imunologia , Methanobrevibacter/patogenicidade , Periodontite/imunologia , Periodontite/microbiologia , Antígenos Arqueais/genética , Chaperonina com TCP-1/genética , Chaperonina com TCP-1/imunologia , Passeio de Cromossomo , Sequência Conservada/imunologia , Reações Cruzadas , DNA Arqueal/análise , Chaperoninas do Grupo II/genética , Interações Hospedeiro-Patógeno , Humanos , Methanobrevibacter/imunologia , Periodontite/sangue , Subunidades Proteicas/genética , Subunidades Proteicas/imunologia , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Alinhamento de Sequência , Análise de Sequência de DNA
19.
Int J Obes (Lond) ; 32(11): 1725-9, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18779827

RESUMO

Recent studies have suggested that macrophages were integrated into adipose tissues to interact with adipocytes, thereby exacerbating inflammatory responses. Furthermore, both adipocytes and macrophages appear to express toll-like receptor-4 (TLR-4), and free fatty acids may stimulate cells through TLR-4. Herein, we analyzed genes differentially expressed in adipocytes when co-cultured with macrophages in the presence of a ligand for TLR-4, bacterial lipopolysaccharide (LPS). RAW264.7, a murine macrophage cell line and differentiated 3T3-L1 adipocytes were co-cultured using a transwell system. Genes differentially expressed in adipocytes were analyzed by the DNA microarray method following 4, 8, 12 and 24 h stimulation with 1 ng ml(-1) of Escherichia coli LPS. Randomly selected genes with high expressions were confirmed by quantitative methods at both the gene and the protein level. Co-culture of macrophages and adipocytes with a low LPS concentration (1 ng ml(-1)) markedly upregulated gene expressions associated with inflammation and/or angiogenesis, such as those of interleukin-6 (IL-6), MCP-1, RANTES and CXCL1/KC, in adipocytes. Furthermore, several genes associated with insulin resistance were differentially expressed. Upregulations of genes encoding MCP-1, RANTES and CXC/KC were confirmed by quantitative methods. These results suggest that ligands for TLR-4 stimulate both adipocytes and macrophages to upregulate the expressions of many genes associated with inflammation and/or angiogenesis.


Assuntos
Adipócitos/imunologia , Endotoxinas/imunologia , Macrófagos/imunologia , Receptor 4 Toll-Like/imunologia , Células 3T3-L1/metabolismo , Animais , Linhagem Celular/metabolismo , Endotoxinas/genética , Expressão Gênica , Camundongos , Análise em Microsséries , Receptor 4 Toll-Like/genética , Regulação para Cima
20.
J Chemother ; 20(3): 319-23, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18606586

RESUMO

The present study aimed to examine the peritoneal pharmacokinetics and pharmacodynamic exposure of intravenous cefotiam. One gram of cefotiam was administered to eight patients before abdominal surgery. Venous blood and peritoneal fluid (PF) samples were obtained at the end of infusion (0.5 h) and 1, 2, 3, 4, 5, and 6 h afterwards. The drug concentrations in the plasma and PF were determined, analyzed pharmacokinetically, and used for a stochastic simulation with minimum inhibitory concentration (MIC) data. Cefotiam penetrated well into the PF with the area under the drug concentration-time curve ratio of 0.88 +/- 0.18 (mean +/- SD, n = 8). Regarding the pharmacodynamic exposures against Escherichia coli and Klebsiella species, the probabilities of attaining the bacteriostatic target (40% of the time above MIC) in the PF using 0.5 g every 12 h, 1 g every 12 h, and 2 g every 12 h were 88.3-93.6%. However, 1 g every 8 h was needed for 89.7 and 91.6% probabilities of attaining the bactericidal target (70% of the time above MIC). These results should help us to understand better the peritoneal pharmacokinetics of cefotiam while also helping us to choose the appropriate dosage for intra-abdominal infections.


Assuntos
Antibacterianos/farmacocinética , Líquido Ascítico/metabolismo , Infecções Bacterianas/tratamento farmacológico , Cefotiam/farmacocinética , Infecção da Ferida Cirúrgica/tratamento farmacológico , Cavidade Abdominal/microbiologia , Cavidade Abdominal/cirurgia , Adulto , Antibacterianos/administração & dosagem , Antibacterianos/farmacologia , Cefotiam/administração & dosagem , Cefotiam/farmacologia , Escherichia coli/efeitos dos fármacos , Feminino , Humanos , Injeções Intravenosas , Klebsiella/efeitos dos fármacos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Método de Monte Carlo , Estudos Prospectivos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...