RESUMO
Insulin-like growth factor I (IGF-I) is essential for muscle and bone development and a primary mediator of growth hormone (GH) actions. While studies have elucidated the importance of IGF-I specifically in muscle or bone development, few studies to date have evaluated the relationship between muscle and bone modulated by IGF-I in vivo, during post-natal growth. Mice with muscle-specific IGF-I overexpression (mIgf1+/+) were utilised to determine IGF-I- and muscle-mass-dependent effects on craniofacial skeleton development during post-natal growth. mIgf1+/+ mice displayed accelerated craniofacial bone growth when compared to wild-type animals. Virus-mediated expression of IGF-I targeting the masseter was performed to determine if post-natal modulation of IGF-I altered mandibular structures. Increased IGF-I in the masseter affected the mandibular base plane angle in a lateral manner, increasing the width of the mandible. At the cellular level, increased muscle IGF-I also accelerated cartilage thickness in the mandibular condyle. Importantly, mandibular length changes associated with increased IGF-I were not present in mice with genetic inhibition of muscle IGF-I receptor activity. These results demonstrated that muscle IGF-I could indirectly affect craniofacial growth through IGF-I-dependent increases in muscle hypertrophy. These findings have clinical implications when considering IGF-I as a therapeutic strategy for craniofacial disorders.
Assuntos
Desenvolvimento Ósseo , Fator de Crescimento Insulin-Like I/metabolismo , Animais , Mandíbula , Côndilo Mandibular , Camundongos , MúsculosRESUMO
Chronic kidney disease (CKD)-mineral and bone disorder suggests that fragile bone and vascular disorder might be connected closely in CKD patients. In this study, fracture event was significantly associated with myocardial infarction (MI) in end-stage renal disease patients on hemodialysis (HD), especially for vertebral fractures. INTRODUCTION: CKD-mineral and bone disorder is characterized by biochemical abnormalities, bone disorders, and vascular calcification. We aimed to verify the association between fracture and MI in CKD patients. METHODS: Records for incident CKD stage 3 to 5 patients and patients who initiated HD between July 2014 and June 2018 were retrieved from the Korean Health Insurance Review & Assessment Service Database. Fractures were defined using diagnostic codes and were classified into vertebral, femoral, and other site fractures. MI was defined using a combination of MI diagnostic codes and related procedure codes. Multiple logistic regressions and 1:1 propensity score matching analysis were conducted. RESULTS: A total of 38,935 patients (HD, 11,379; pre-dialysis CKD, 27,556) were included in this study. A total of 5,057 (13.0%) patients experienced fracture, and 1,431 (3.7%) patients had MI. Multiple logistic regression analysis showed that fracture was significantly associated with MI in the HD group (odds ratio (OR) 1.34, P = 0.024), but not in the pre-dialysis CKD group (OR 1.04, P = 0.701). After propensity score matching for age, gender, and diabetes mellitus between patients with and without fracture, fracture still significantly correlated with MI in HD patients (OR 1.47, P = 0.034) but not in patients with pre-dialysis CKD (OR 1.04, P = 0.751). Subgroup analysis by fracture site found that vertebral fracture was associated with MI in HD patients (OR 2.11, P = 0.024), but femoral or other site fractures were not. CONCLUSION: In HD patients, fracture was significantly associated with MI, especially for vertebral fractures patients.
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Falência Renal Crônica , Infarto do Miocárdio , Fraturas da Coluna Vertebral , Humanos , Falência Renal Crônica/complicações , Falência Renal Crônica/epidemiologia , Falência Renal Crônica/terapia , Infarto do Miocárdio/complicações , Infarto do Miocárdio/epidemiologia , Diálise Renal , República da Coreia/epidemiologia , Fatores de Risco , Fraturas da Coluna Vertebral/epidemiologia , Fraturas da Coluna Vertebral/etiologiaRESUMO
BACKGROUND AND PURPOSE: The objective of this study was to investigate the association between body mass index (BMI) and both initial stroke severity at presentation and functional outcomes after acute ischaemic stroke (AIS) in patients with non-valvular atrial fibrillation (NVAF). METHODS: Patients were categorized on the basis of their BMI into underweight (BMI <18.5, n = 111), normal (18.5 ≤ BMI <25, n = 1036) and overweight to obese (BMI ≥25, n = 472) groups. Initial stroke severity was assessed using the National Institutes of Health Stroke Scale (NIHSS) score and functional outcomes were assessed using the modified Rankin Scale score at discharge. The differences in stroke severity and functional outcomes were compared between groups using robust log-linear regression with a Poisson distribution and binary logistic regression analysis. RESULTS: A total of 1619 AIS patients with NVAF from six hospitals were included. Compared with the NIHSS scores [median 5, interquartile range (IQR) 2-14] of normal-weight patients, the NIHSS scores (median 9, IQR 4-19) of underweight patients were more likely to be higher, whereas those of overweight to obese patients were lower (median 4, IQR 1-12) (P < 0.001). In terms of functional outcomes after stroke, underweight patients had a higher risk of poor functional outcomes (odds ratio 1.78, 95% confidence interval 1.09-2.56, P = 0.01) but overweight to obese patients had no significant difference in functional outcomes compared with normal-weight patients. CONCLUSION: An inverse association was found between BMI and stroke severity in AIS patients with NVAF. This suggests the presence of an obesity paradox for short-term outcomes in patients with NVAF.
Assuntos
Fibrilação Atrial , Isquemia Encefálica , AVC Isquêmico , Fibrilação Atrial/complicações , Fibrilação Atrial/epidemiologia , Índice de Massa Corporal , Isquemia Encefálica/complicações , Isquemia Encefálica/epidemiologia , Humanos , Fatores de RiscoRESUMO
While the association between hepatitis C virus (HCV) infection and diabetes has been established, the relationship between hepatitis B virus (HBV) infection and diabetes remains unclear. Therefore, we compared the association between diabetes development in HBV, HCV and co-infected (HBV/HCV) patients to that in noninfected participants using population-based cohort data. We used the National Health Insurance Service-National Sample Cohort, which consists of 514 791 randomly selected persons among those who underwent health check-ups from 2002 to 2003 aged 40-79 years. Adults found to have HBV or HCV infection from 2002 to 2003, without a prior history of diabetes, were selected as subjects. Competing risk regression models were used to estimate cumulative incidence and hazards ratios (HRs) of diabetes development. The cumulative incidences, incidence densities and HRs of diabetes were highest in the co-infected group, followed by those in the HCV-, HBV- and noninfected groups. The 12-year cumulative incidences were as follows: 42.0% in HBV/HCV-, 32.9% in HCV-, 23.9% in HBV- and 18.3% in the noninfected groups. The incidence density per 1000 person-years was 55.0, 51.5, 38.2 and 28.2 for the HBV/HCV-, HCV-, HBV- and noninfected groups, respectively. The adjusted HRs for diabetes were 1.90, 1.68 and 1.41 for the HBV/HCV-, HCV- and HBV-infected groups, respectively. Our findings suggest that both HCV and HBV infections are associated with the development of diabetes; therefore, prevention of, screening for, and treatment of both may reduce the risk of diabetes in these patients.
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Diabetes Mellitus/epidemiologia , Hepatite B/complicações , Hepatite C/complicações , Adulto , Idoso , Estudos de Coortes , Coinfecção/complicações , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , República da Coreia/epidemiologia , Medição de RiscoRESUMO
AIM: To evaluate the diagnostic performance of three-dimensional (3D) image shear-wave elastography (SWE) for differentiating benign from malignant breast masses compared to two-dimensional (2D) SWE and B-mode ultrasound (US). MATERIALS AND METHODS: This study consisted of 205 breast lesions from 199 patients who underwent B-mode US and SWE before biopsy from January 2014 to March 2016. Quantitative elasticity values (maximum and mean elasticity, Emax and Emean) obtained from 2D and 3D SWE (axial, sagittal, and coronal images) were reviewed retrospectively, in addition to the histopathological findings including immunohistochemistry profiles (luminal A, luminal B, human epidermal growth factor receptor 2 (HER2)-enriched, and triple-negative breast cancer) in cases of malignancy. Histopathological findings were regarded as the reference standard. The diagnostic performance of each data set was evaluated using the area under the receiver operating characteristic (ROC) curve (AUC) analysis to compare sensitivity and specificity. RESULTS: Among 205 lesions, 105 (51.22%) were malignant and 100 (48.78%) were benign. Compared to benign masses, malignant masses had higher values of Emax and Emean on both 2D and 3D SWE, the differences of which were statistically significant (p<0.001). The AUCs of 2D, 3D axial, and sagittal SWE were significantly higher than that of 3D coronal SWE (p<0.05). In addition, the sensitivities of axial, sagittal, and coronal 3D SWE were all higher than that of 2D SWE for Emean (81.9%, 87.6%, and 89.5% versus 70.5%, respectively, p<0.05). Conversely, the specificity of 2D and 3D axial SWE was higher than that of 3D sagittal and coronal SWE (Emax, 84%, 83% versus 76%, 73%; Emean, 85%, 81% versus 68%, 50%, respectively, p<0.05). We also assessed changes in Breast Imaging-Reporting and Data System (BI-RADS) category 3 and category 4a lesions by adding each of the parameters for 2D and 3D SWE in B-mode US. The specificity, PPV, and accuracy of combined 2D or combined 3D SWE with B-mode US was statistically higher than that of B-mode US alone for differentiating benign and malignant lesions (p<0.05). CONCLUSIONS: Among SWE images, 2D SWE, and 3D SWE axial and sagittal images exhibited superior diagnostic performance compared to 3D coronal images. Addition of 3D SWE images to B-mode US improved the diagnostic performance for distinguishing benign from malignant masses.
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Neoplasias da Mama/diagnóstico por imagem , Técnicas de Imagem por Elasticidade/métodos , Imageamento Tridimensional/métodos , Ultrassonografia Mamária/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Mama/diagnóstico por imagem , Diagnóstico Diferencial , Feminino , Humanos , Pessoa de Meia-Idade , Curva ROC , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade , Adulto JovemRESUMO
BACKGROUND: Allergic contact dermatitis is a common diagnosis in eyelid dermatitis. Sensitization to metals is prevalent in eyelid dermatitis and colour cosmetic products are frequently suspected as the source of metal exposure. OBJECTIVE: To investigate the contact allergens for eyelid dermatitis and to assess metal contents in eye shadow products. METHODS: Data were collected in the department of dermatology of Ewha Womans University hospital from December 1998 to February 2014. A total of 983 patients were patch tested during the period and 67 patients had eyelid dermatitis among them. To examine metal elements in colour cosmetic products for eyes, randomly selected 10 eye shadows were analysed. RESULTS: Frequent allergens were metals, thiomersal and phenylenediamine in patients with eyelid dermatitis. The sensitization rates of individual allergens were not significantly different between patients with eyelid dermatitis and without eyelid dermatitis. All 10 eye shadow products contained more than 5 ppm of at least one element, nickel, cobalt or chromium. CONCLUSION: Metals were top-rank allergens in patients with eyelid dermatitis as in the remaining patients patch tested. The eye shadow products contained significant amount of nickel, cobalt or chromium to elicit allergic reactions.
Assuntos
Cosméticos/química , Dermatite Alérgica de Contato/etiologia , Metais/efeitos adversos , Metais/análise , Adulto , Feminino , Humanos , MasculinoRESUMO
Nodular fasciitis is a benign fibroblastic proliferation in soft tissue that is most commonly found in the upper extremities, trunk, head, and neck region. Its occurrence in the breast has been rarely reported. The most characteristic features are the sudden appearance and rapid growth of a palpable lesion. Nodular fasciitis can clinically, radiologically, and histopathologically mimic a breast carcinoma. We present a case of nodular fasciitis of the breast and a review of the relevant literature.
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Doenças Mamárias/diagnóstico por imagem , Fasciite/diagnóstico por imagem , Ultrassonografia Mamária/métodos , Biópsia com Agulha de Grande Calibre , Mama/lesões , Mama/patologia , Doenças Mamárias/patologia , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Diagnóstico Diferencial , Fasciite/patologia , Feminino , Humanos , Ultrassonografia Doppler em Cores , Ultrassonografia de Intervenção , Ferimentos não Penetrantes/complicações , Ferimentos não Penetrantes/diagnóstico por imagem , Adulto JovemRESUMO
BACKGROUND: The 1997 international consensus conference on renal cell cancer (RCC) prognosis suggested erythrocyte sedimentation rate (ESR), alkaline phosphatase (ALP), and anaemia as prognostic biomarkers, but most studies reviewed were limited by small sample sizes. METHODS: The Cox proportional hazards model was used to evaluate whether ESR, ALP, haemoglobin (Hb), and haematocrit (Hct) could predict survival outcomes in 1307 patients with clear cell RCC (ccRCC) who underwent nephrectomy during 1994-2008. RESULTS: During a median follow-up of 43 months, we found that the patients with preoperative high levels of ESR, had a 2.10-fold (95% confidence interval (CI): 1.21-3.67) greater risk of dying from RCC compared with patients with low levels (normal range). Patients with preoperative anaemia, assessed by Hb and Hct, had a 3.11-fold (95% CI: 1.17-8.25) and 6.20-fold (95% CI: 2.30-16.72) greater risk of dying from other illnesses, respectively, compared with patients without anaemia. ALP levels were not associated with ccRCC patients' survival. These associations for ESR and anaemia were more pronounced in patients with body mass index (BMI) <25 compared with patients with BMI ≥ 25 kg m(-2). CONCLUSION: Preoperative high ESR, but not ALP, was a significant predictor for cancer-specific survival among ccRCC patients. Anaemia increases the risk of death from other illness.
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Carcinoma de Células Renais/sangue , Carcinoma de Células Renais/mortalidade , Neoplasias Renais/sangue , Neoplasias Renais/mortalidade , Idoso , Fosfatase Alcalina/sangue , Anemia/etiologia , Biomarcadores Tumorais/sangue , Sedimentação Sanguínea , Índice de Massa Corporal , Carcinoma de Células Renais/cirurgia , Feminino , Humanos , Neoplasias Renais/cirurgia , Masculino , Pessoa de Meia-Idade , Prognóstico , Taxa de SobrevidaRESUMO
High-resolution laser-based angle-resolved photoemission measurements have been carried out on Bi2Sr2CaCu2O(8+δ) (Bi2212) superconductors to investigate momentum dependence of electron coupling with collective excitations (modes). Two coexisting energy scales are clearly revealed over a large momentum space for the first time in the superconducting state of the overdoped Bi2212 superconductor. These two energy scales exhibit distinct momentum dependence: one keeps its energy near 78 meV over a large momentum space while the other changes its energy from â¼40 meV near the antinodal region to â¼70 meV near the nodal region. These observations provide a new picture on momentum evolution of electron-boson coupling in Bi2212 that electrons are coupled with two sharp modes simultaneously over a large momentum space in the superconducting states. Their unusual momentum dependence poses a challenge to our current understanding of electron-mode-coupling and its role for high-temperature superconductivity in cuprate superconductors.
RESUMO
BACKGROUND: A wart is a skin lesion caused by infection with human papillomavirus (HPV). Contact immunotherapy is one of the many therapeutic options that have been used to treat warts; however, the effectiveness of contact immunotherapy differs from patient to patient, and the cause of this variation in clinical response is unclear. AIM: To assess cytokine changes in patients after contact immunotherapy with squaric acid dibutylester (SADBE). METHODS: In total, 21 patients with warts and 9 healthy control subjects were enrolled in the study. The frequencies of CD3+ T cells expressing interleukin (IL)-4, IL-10, IL-12, tumour necrosis factor-α and interferon-γ were measured by flow cytometry analysis of peripheral blood at baseline in both patients and controls, and after SADBE treatment in patients. RESULTS: Lower expression of IL-4 and higher expression of IL-12 in CD3+ T cells were found in patients compared with controls. The percentage of CD3+/IL-4+ T cells significantly increased after contact immunotherapy in all responders, but was significantly higher in those with an excellent response, who also had a significantly higher percentage of CD3+/IL-10+ T cells. The patients with an excellent response also had a significant decrease in the percentage of CD3+/IL-12+ T cells, and the percentage of CD3+/IL-4+ T cells normalized. CONCLUSIONS: Response to contact immunotherapy can vary depending on the types of cytokine changes produced by treatment. An excessive shift to a Th2 pattern and increased IL-10 production after contact immunotherapy may hinder clearance of HPV.
Assuntos
Adjuvantes Imunológicos/uso terapêutico , Ciclobutanos/uso terapêutico , Citocinas/metabolismo , Imunoterapia/métodos , Verrugas/tratamento farmacológico , Adolescente , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Interferon gama/metabolismo , Interleucinas/metabolismo , Masculino , Pessoa de Meia-Idade , Linfócitos T/imunologia , Fator de Necrose Tumoral alfa/metabolismo , Verrugas/imunologia , Adulto JovemRESUMO
BACKGROUND: Transcutaneous electrical nerve stimulation (TENS) has been used to reduce muscle spasticity and improve locomotion in stroke survivors. We speculate that acute changes in gait performance after TENS mediate functional improvement in the long-term. However, no previous study has investigated the effect of TENS on ankle kinetics and kinematics during walking in stroke survivors. PURPOSE: We aimed to investigate whether TENS applied over the paretic leg could rapidly improve the plantar flexion moment and ankle kinematics in chronic stroke survivors with lower limb paresis. METHODS: Twenty chronic stroke survivors were recruited. They underwent 30 min of TENS over the area innervated by the common peroneal nerve on the paretic leg. Three-dimensional (3D) motion capture was performed and ankle plantar flexor spasticity was assessed before and immediately after stimulation. Ankle kinematics and kinetic and spatiotemporal data were collected using 3D motion capture. Ankle plantar flexor spasticity was assessed using the Modified Tardieu Scale. PRINCIPAL RESULTS: A significant increase in the ankle plantar flexion moment of the paretic side during the pre-swing phase was observed immediately after stimulation (p = 0.009, maximal mean difference = 0.035, 95%CI = 0.0125 to 0.0575). The step length of the paretic limb also increased significantly after stimulation (p = 0.023, mean difference = -0.02, 95%CI = -0.04 to -0.004). TENS had no immediate effect on paretic ankle spasticity, as measured by the Modified Tardieu Scale, or on other temporo-spatial parameters. CONCLUSION: The findings support the use of TENS to improve the motor function and gait pattern in chronic stroke survivors. The study indicated that the application of TENS to the paretic leg before gait training might improve rehabilitation outcomes. Future studies investigating the effects of TENS on functional outcomes, the optimal stimulation duration, and assessing spasticity using more sensitive measures are warranted.
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Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Estimulação Elétrica Nervosa Transcutânea , Marcha , Humanos , Espasticidade Muscular/reabilitação , Acidente Vascular Cerebral/terapia , Reabilitação do Acidente Vascular Cerebral/métodos , Sobreviventes , Estimulação Elétrica Nervosa Transcutânea/métodosRESUMO
BACKGROUND: Recanalization is strongly associated with outcomes after thrombolytic treatment. Cardiac emboli are known as better response to fibrinolytic agents because they are fibrin-rich; however, cardioembolic stroke itself is associated with poor outcomes and high mortality. Completeness of recanalization may therefore affect the outcome of cardioembolic stroke. We investigated whether degree of recanalization influences outcomes following fibrinolytic therapy in cardioembolic stroke. METHODS: Consecutive stroke patients with relevant artery occlusions on baseline CT angiography who had received thrombolytic treatment were enrolled. Completeness of recanalization was assessed by the Thrombolysis in Myocardial Infarction (TIMI) grade, which was compared between patients with and without cardiac sources of embolism (CSE). We also investigated independent predictors of poor outcome (modified Rankin scale score 3-6) at 3 months. RESULTS: Of the 127 patients enrolled, 65 (51%) had one or more CSE. Although the overall recanalization rates (TIMI 2 or 3) in patients with CSE (65%) and patients without CSE (68%) were similar (P=0.710), patients with CSE were less likely to show complete recanalization (TIMI 3) compared with those without CSE (19% vs. 39%, P=0.011). Multivariate analysis revealed that CSE was associated with failure of complete recanalization (OR 2.809, 95% CI 1.097-7.192) and was an independent predictor of poor outcome at 3months (OR 3.629, 95% CI 1.205-8.869). CONCLUSIONS: In cardioembolic strokes, failure of complete recanalization following thrombolytic therapy was frequent and was associated with poor outcome after thrombolysis.
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Recuperação de Função Fisiológica , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/patologia , Terapia Trombolítica , Idoso , Angiografia Digital , Feminino , Cardiopatias/complicações , Humanos , Embolia Intracraniana/tratamento farmacológico , Embolia Intracraniana/etiologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Ativador de Plasminogênio Tecidual/uso terapêutico , Ativador de Plasminogênio Tipo Uroquinase/uso terapêuticoRESUMO
BACKGROUND AND PURPOSE: Abruptly discontinuing warfarin may induce a rebound prothrombotic state. Thrombolytic agents may also paradoxically induce prothrombotic conditions, which include platelet activation and thrombin generation. Therefore, prothrombotic states may be enhanced by withdrawing warfarin in patients under thrombolytic treatment. This study was aimed to determine whether patients with warfarin withdrawal have different clinical outcomes from those without warfarin use after thrombolytic treatment. METHODS: A total of 148 consecutive patients with atrial fibrillation who were not on anticoagulants at admission and who received thrombolysis were included in this study. We compared the outcomes between a warfarin withdrawal group and a no-warfarin group. RESULTS: Fourteen patients (9.5%) were included in the warfarin withdrawal group. Although baseline National Institute of Health Stroke Scale (NIHSS) scores, recanalization rates, and hemorrhage frequencies did not differ between the groups, the warfarin withdrawal group showed poorer outcomes. Increased NIHSS scores during the first 7days were more frequent in the warfarin withdrawal group (57.1% vs. 26.9%, P=0.029). The median percent improvement in NIHSS scores at 24h after thrombolysis was also lower in the warfarin withdrawal group. After adjusting for covariates, warfarin withdrawal was a strong predictor of poor functional outcome at 3months (modified Rankin score≥3) (odds ratio, 17.067, 95% CI 2.703-107.748). CONCLUSIONS: Discontinuing warfarin was associated with early neurologic deterioration and poor long-term outcomes after thrombolytic treatment.
Assuntos
Anticoagulantes/uso terapêutico , Recuperação de Função Fisiológica/efeitos dos fármacos , Acidente Vascular Cerebral/tratamento farmacológico , Terapia Trombolítica/efeitos adversos , Varfarina/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Fibrilação Atrial/tratamento farmacológico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ativador de Plasminogênio Tecidual/efeitos adversos , Ativador de Plasminogênio Tipo Uroquinase/efeitos adversosRESUMO
BACKGROUND: Perforating artery territorial infarction (PAI) is usually a small artery disease (SAD). However, it may also result from branch artery occlusion or arterial embolism from the proximal atherosclerotic lesions. We hypothesized that patients with PAI caused by a SAD may have a distinct pattern of systemic artery involvement from those with PAI caused by large artery diseases. METHODS: We investigated retrospectively 329 consecutive patients with PAI who had angiographic studies. Patients were grouped according to the presence or absence of atherosclerosis in the parent artery or relevant artery: no arterial lesion (NAL), relevant artery atherosclerosis (RAA) and parent artery atherosclerosis (PAA). The relevant artery was defined as any artery which can cause index stroke. The parent artery was defined as an original artery that branches out and forms small artery which was responsible for index PAI. Systemic evidence of atherosclerosis and risk factors were compared. RESULTS: Of the 329 patients with PAI, 109 had RAA, 45 had PAA and 175 had neither RAA nor PAA. There were no differences amongst the groups in the classic risk factors for atherosclerosis. Evidence of atherosclerosis in arterial beds other than the relevant artery to the infarction (other cerebral arteries, coronary arteries, descending aorta and peripheral arteries) was significantly lower in the NAL group (49.7%) than in either the PAA group (88.9%) or RAA group (93.6%). CONCLUSIONS: Perforating artery territorial infarction with RAA or PAA when compared to PAI without atherosclerosis showed different involvement patterns of systemic atherosclerosis, suggesting potentially different aetiological mechanisms.
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Aterosclerose/complicações , Aterosclerose/patologia , Infarto Encefálico/etiologia , Infarto Encefálico/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Artérias Cerebrais/patologia , Circulação Cerebrovascular , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
We demonstrate the transmission of 108-Gb/s polarization-division-multiplexed (PDM) 16-ary amplitude- and differential phase-shift-keying (16ADPSK) signal by using a non-coherent receiver. We generate the 16ADPSK signal by using a differential 8-ary phase-shift-keying (D8PSK) modulator and a phase-distortion-free amplitude-shift-keying (ASK) modulator. On the other hand, the receiver is implemented by using a delay interferometer based on a 3x3 fiber coupler and the data-aided phase-noise estimation (DAPNE) algorithm. By using these transmitter and receiver, we achieve a nearly quantum-limited receiver sensitivity in the back-to-back condition. In addition, we examine the possibility of transmitting 108-Gb/s signals on a 25-GHz grid without using the coherent detection technology. The results show that we can secure a sufficient optical-signal-to-noise (OSNR) margin after the transmission of 80-km long dispersion managed link. The achieved spectral efficiency is 4.0 bit/s/Hz.
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Tecnologia de Fibra Óptica/instrumentação , Dispositivos Ópticos , Processamento de Sinais Assistido por Computador/instrumentação , Transdutores , Simulação por Computador , Desenho Assistido por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Luz , Micro-Ondas , Modelos Teóricos , Espalhamento de Radiação , Telecomunicações/instrumentaçãoRESUMO
We report a new optical performance monitoring technique based on the amplitude and phase histograms of the optical signal. The amplitude and phase histograms are obtained by using an intradyne receiver and the asynchronous delay-tap sampling method. From these histograms, we can evaluate the amplitude and phase Q-factors of the optical signal regardless of its modulation format. In addition, by using these Q-factors, we can estimate the bit-error rate (BER) of the monitoring signal.
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Algoritmos , Análise de Falha de Equipamento/métodos , Dispositivos Ópticos , Processamento de Sinais Assistido por ComputadorRESUMO
BACKGROUND AND PURPOSE: Although it has been suggested that bilateral symmetry of atherosclerosis can be found in paired arteries, including external carotid arteries and femoral arteries, it has remained unknown in intracranial arteries. We determined whether bilateral symmetry (a mirror pattern) of atherosclerosis presents in the entire cerebral arterial system. METHODS: Angiographic findings of 795 consecutive patients with ischaemic stroke, after excluding those with cardiac sources of embolism or other causes of stroke, were reviewed retrospectively. The presence (location) and severity (the degree of stenosis) of atherosclerosis were compared between left and right sides at 26 predetermined arteries/segments. RESULTS: We found 2230 lesions in predetermined segments/arteries from 669 patients. Amongst 509 patients with atherosclerotic lesions at two or more arteries/segments, mirror patterns were observed in 312 patients (61.3%). The mirror pattern increased steeply as the number of atherosclerotic arteries increased and was most frequently found in the carotid bulb (C1, 26.7%), followed by the middle cerebral artery (M1, 14.1%). The severity of stenosis was also correlated between left and right sides, and the correlation was highest in the C1 (r = 0.40, P < 0.001). Multiple logistic regression analyses revealed that the mirror patterns of atherosclerosis were more obvious in C1 and associated with a past history of ischaemic stroke and the number of stenotic lesions. CONCLUSION: Atherosclerosis in cerebral arteries may develop and progress in a mirror pattern. In patients with cerebral artery atherosclerosis, the occurrence and progression of atherosclerosis in the contralateral cerebral artery should be considered during follow-up examination.
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Artérias Cerebrais/patologia , Infarto Cerebral/patologia , Arteriosclerose Intracraniana/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Artérias Cerebrais/diagnóstico por imagem , Infarto Cerebral/complicações , Infarto Cerebral/diagnóstico por imagem , Progressão da Doença , Feminino , Humanos , Arteriosclerose Intracraniana/complicações , Arteriosclerose Intracraniana/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Seleção de Pacientes , Radiografia , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença , UltrassonografiaRESUMO
BACKGROUND AND PURPOSE: Patients who are being admitted to a hospital due to diseases other than stroke may develop a stroke (in-hospital stroke; IHS). METHODS: We enrolled 111 consecutive patients who developed IHS outside a neurology ward during a 5-year period at a single hospital. The frequency, characteristics, and outcomes for IHS patients were compared with patients who develop ischaemic stroke outside of the hospital (out-of-hospital stroke; OHS). RESULTS: Forty-six percent of IHS occurred in the department of cardiology or cardiovascular surgery and 60% were associated with surgery or procedures. In comparison with the OHS patient group, the IHS patient group showed an increased frequency of cardiac disease, leukocytosis, and anemia. Cardioembolism, stroke of other determined etiologies, and an incomplete evaluation were more common in the IHS group, whereas large artery atherosclerosis was more frequent in the OHS group. The IHS group had up to a 10-fold higher mortality than the OHS group, with sepsis being the most common cause of death in the IHS group. CONCLUSIONS: IHS has distinct etiologies and stroke mechanisms from OHS. The prevention and management of infection could decrease mortality in IHS patients.
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Pacientes Internados/estatística & dados numéricos , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/fisiopatologia , Causas de Morte , Humanos , Fatores de RiscoRESUMO
BACKGROUND AND PURPOSE: The tuberothalamic artery (TTA), one of the arteries supplying the paramedian thalamic area, is peculiar because it originates from the posterior communicating artery (p-comA), which connects the vertebrobasilar and carotid systems. METHODS: From Stroke Registry, 23 consecutive patients with an acute infarction involving the TTA were selected. We investigated the mechanism of TTA infarction. RESULTS: Fourteen of 23 patients (61%) had coexisting infarctions outside the TTA territory (carotid in three, vertebrobasilar in seven, and both carotid and vertebrobasilar arteries in four patients). Coexisting lesions were most common in the posterior thalamoperforating arterial territory (seven patients). Eleven out of 14 patients (79%) with coexisting lesions had embolic sources from the heart or proximal atherosclerotic arteries, and cardioembolism was the most common mechanism. However, eight of the nine patients with isolated tuberothalamic lesions were classified as small vessel occlusions. More patients with embolic sources had visible p-comA or fetal-type posterior cerebral arteries. The vertebrobasilar arterial system played a more dominant role in developing tuberothalamic infarction than the carotid arterial system. CONCLUSIONS: Isolated TTA infarctions are rare and mostly because of small vessel occlusion. Patients with coexisting infarctions outside TTA territory usually have an embolic source, predominantly vertebral artery atherosclerosis.