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61.
Alexandros Zafiropoulos Eleni Fthenou Georgia Chatzinikolaou George N. Tzanakakis 《Connective tissue research》2013,54(3-4):153-156
Platelet derived growth factor (PDGF) is involved in the autocrine growth stimulation of normal and malignant cells, the stimulation of angiogenesis, and the recruitment and regulation of tumor fibroblasts. PDGF has been shown to physically interact with glycosaminoglycans which are abundant in the extracellular microenvironment. The present review discusses the effects of glycosaminoglycans on the functions mediated by the PDGF on cells of mesenchymal origin. Recent studies have demonstrated that both soluble and surface bound glycosaminoglycan chains can modulate PDGF-BB isoform signaling depending on the cell type. These data demonstrated that the microenvironment rich in GAGs/PGs is able to significantly modify the cellular response to PDGF-BB signaling in a critical way for cell growth and differentiation. 相似文献
62.
Julio Fernandez-Mendoza Fan He Kristina Puzino Gregory Amatrudo Susan Calhoun Duanping Liao Alexandros N Vgontzas Edward Bixler 《Sleep》2021,44(1)
Study ObjectivesInsomnia with objective short sleep duration has been previously associated with adverse cardiometabolic health outcomes as well as poorer cognitive performance in otherwise noncognitively impaired adults. However, studies demonstrating an increased prevalence of cognitive impairment (CI) in this insomnia phenotype are lacking.MethodsWe analyzed data from Penn State Adult Cohort (N = 1,524; 48.9 ± 13.4 years; 53.4% women). Self-reported sleep difficulty was defined as normal sleep (n = 899), poor sleep (n = 453), and chronic insomnia (n = 172). Objective short sleep duration was defined as less than 6-h of sleep, based on in-lab, 8-h polysomnography. CI (n = 155) and possible vascular cognitive impairment (pVCI, n = 122) were ascertained using a comprehensive neuropsychological battery. Analyses adjusted for age, sex, race, education, body mass index, apnea/hypopnea index, smoking, alcohol, psychoactive medication, and mental and physical health problems.ResultsParticipants who reported poor sleep or chronic insomnia and slept objectively less than 6 hours were associated with a 2-fold increased odds of CI (OR = 2.06, 95% confidence limits [CL] = 1.15–3.66 and OR = 2.18, 95% CL = 1.07–4.47, respectively) and of pVCI (OR = 1.94, 95% CL = 1.01–3.75 and OR = 2.33, 95% CL = 1.07–5.06, respectively). Participants who reported poor sleep or chronic insomnia and slept objectively more than 6 hours were not associated with increased odds of either CI (OR = 0.72, 95% CL = 0.30–1.76 and OR = 0.75, 95% CL = 0.21–2.71, respectively) or pVCI (OR = 1.08, 95% CL = 0.42–2.74 and OR = 0.76, 95% CL = 0.16–3.57, respectively).ConclusionsInsomnia with objective short sleep duration is associated with an increased prevalence of CI, particularly as it relates to cardiometabolic health (i.e. pVCI). These data further support that this insomnia phenotype may be a more biologically severe form of the disorder associated with cardiovascular, cerebrovascular, and neurocognitive morbidity. 相似文献
63.
Englezakis Alexandros Gozalpour Elnaz Kamran Mohammed Fenner Katherine Mele Elisa Coopman Karen 《Journal of artificial organs》2021,24(4):473-484
Journal of Artificial Organs - Understanding the active transport of substrates by the kidney in the renal proximal convoluted tubule is crucial for drug development and for studying kidney... 相似文献
64.
65.
Vasileios Kalles Maria Dasiou Georgia Doga Ioannis Papapanagiotou Evangelos A Konstantinou Alexandros Mekras Theodoros Mariolis-Sapsakos Nikolaos Anastasiou 《International surgery》2015,100(3):444-449
Intercostal hernias are rare, and usually occur following injuries of the thoracic wall. The scope of this report is to present a case of a 53-year-old obese patient that developed a transdiaphragmatic intercostal hernia. The patient presented with a palpable, sizeable, reducible mass in the right lateral thoracic wall, with evident bowel sounds in the area, 6 months after a motor-vehicle accident. On computed tomography (CT), the hernia sac contained part of the liver and part of the ascending colon. A surgical repair of the defect was performed, using a prosthetic patch. The patient''s postoperative course was uneventful and she remains recurrence free at 12 months after surgery. Intercostal hernias should be suspected following high-impact injuries of the thoracic wall, and CT scans will facilitate the diagnosis of intercostal hernia. We consider the surgical repair of the defect, with placement of a prosthetic mesh, as the treatment of choice to ensure a favorable outcome.Key words: Hernia, Transdiaphragmatic, Intercostal, Abdominal, MeshThe herniation of abdominal contents through the thoracic wall, as a result of the disruption of diaphragmatic and/or intercostal muscles, is an uncommon clinical entity.1–3 This condition is usually reported to occur following penetrating or blunt injuries of the thoracic wall.4 However, there are several cases that have been described to be a consequence of a coughing–spell rib fracture, usually in patients with other predisposing factors such as chronic obstructive pulmonary disease, asthma, advanced age, or osteoporosis.1,3,4The present report describes a case of a middle-aged obese patient that developed a transdiaphragmatic intercostal hernia involving the liver and the ascending colon 6 months after a traumatic incident. The underlying mechanism, the anatomical and diagnostic considerations, as well as the treatment options are also discussed. 相似文献
66.
Surgical complications after kidney transplantation: different impacts of immunosuppression,graft function,patient variables,and surgical performance 下载免费PDF全文
Martina Koch Alexandros Kantas Katja Ramcke Anna I. Drabik Björn Nashan 《Clinical transplantation》2015,29(3):252-260
The population of kidney transplant (KTx) recipients often has complex medical and immunological conditions. Surgical complications (SCs) contribute to the increasing morbidity and costs in these patients. We analyzed the risk factors for SC in 405 KTx patients treated using defined immunosuppressive regimens according to their clinical and immunological risk profile: (1) standard immunosuppression (SIS) with IL‐2 receptor mAb, CNI, and (a) mycophenolic acid (MPA) or (b) mTOR inhibitor; and (2) more intense immunosuppression (IIS) with (a) ATG or (b) the additional use of plasma exchange and B‐ and T‐cell‐depleting agents. In a mixed effects logistic regression model, we identified the following risk factors for SC: male gender, diabetes, and post‐operative dialysis. No difference was found between the patients who received SIS with MPA and those who received mTOR inhibitors. The risk of suffering complications with IIS increases with age. In addition to IIS, diabetes was a risk for wound healing disorders. Therapeutic anticoagulation and a third or subsequent retransplantation increased the rate of bleeding. We did not identify immunosuppression or patient demographics as risk factors for lymphoceles or ureter complications; however, we demonstrated that the surgeon had a significant impact on severe complications, especially those of the ureter. 相似文献
67.
Physical inactivity in patients with rheumatoid arthritis: data from twenty-one countries in a cross-sectional, international study 总被引:1,自引:0,他引:1
Sokka T Häkkinen A Kautiainen H Maillefert JF Toloza S Mørk Hansen T Calvo-Alen J Oding R Liveborn M Huisman M Alten R Pohl C Cutolo M Immonen K Woolf A Murphy E Sheehy C Quirke E Celik S Yazici Y Tlustochowicz W Kapolka D Skakic V Rojkovich B Müller R Stropuviene S Andersone D Drosos AA Lazovskis J Pincus T;QUEST-RA Group 《Arthritis and rheumatism》2008,59(1):42-50
OBJECTIVE: Regular physical activity is associated with decreased morbidity and mortality. Traditionally, patients with rheumatoid arthritis (RA) have been advised to limit physical exercise. We studied the prevalence of physical activity and associations with demographic and disease-related variables in patients with RA from 21 countries. METHODS: The Questionnaires in Standard Monitoring of Patients with Rheumatoid Arthritis (QUEST-RA) is a cross-sectional study that includes a self-report questionnaire and clinical assessment of nonselected consecutive outpatients with RA who are receiving usual clinical care. Frequency of physical exercise (>or=30 minutes with at least some shortness of breath, sweating) is queried with 4 response options: >or=3 times weekly, 1-2 times weekly, 1-2 times monthly, and no exercise. RESULTS: Between January 2005 and April 2007, a total of 5,235 patients from 58 sites in 21 countries were enrolled in QUEST-RA: 79% were women, >90% were white, mean age was 57 years, and mean disease duration was 11.6 years. Only 13.8% of all patients reported physical exercise>or=3 times weekly. The majority of the patients were physically inactive with no regular weekly exercise: >80% in 7 countries, 60-80% in 12 countries, and 45% and 29% in 2 countries, respectively. Physical inactivity was associated with female sex, older age, lower education, obesity, comorbidity, low functional capacity, and higher levels of disease activity, pain, and fatigue. CONCLUSION: In many countries, a low proportion of patients with RA exercise. These data may alert rheumatologists to motivate their patients to increase physical activity levels. 相似文献
68.
Alexandros?BriasoulisEmail author Emmanuel?Androulakis Theodoros?Christophides Dimitris?Tousoulis 《Heart failure reviews》2016,21(2):169-176
Chronic inflammation underlies a variety of seemingly unrelated conditions including coronary artery disease. The interest in exploring the role of inflammation in heart failure (CHF) arises from earlier observations that circulating pro-inflammatory biomarker levels are elevated in patients with both ischaemic and non-ischaemic cardiomyopathies and correlate with severity of disease and prognosis (McMurray et al. in Eur Heart J 33:1787–1847, 2012; Mosterd and Hoes in Heart 93:1137–1146, 2007; Owan et al. in New Engl J Med 355:251–259, 2006). In acute decompensated HF, pro-inflammatory biomarker levels have been associated with mortality and readmission rates (Cowie et al. in Heart 83:505–510, 2000). Similar to neurohormonal activation and inflammation, production of pro-inflammatory cytokines is a response to stress in an attempt to restore cellular function. However, sustained expression and exposure to cytokines can lead to left ventricular dysfunction, negative inotropic effects, altered cardiac metabolism, myocardial remodelling and HF progression. However, it is unclear whether elevated levels of pro-inflammatory biomarkers, such as high-sensitivity C-reactive protein, signify an ongoing inflammatory process that leads to HF progression, or are merely markers of advanced disease. Beta-blockers, renin–angiotensin–aldosterone axis antagonists, statins and immunosuppressants have been found to decrease the levels of cytokines in small clinical studies of patients with HF (Hobbs et al. in Heart J 28:1128–1134, 2007). However, ‘immunomodulatory’ approaches applied in the RECOVER, RENAISSANCE, ATTACH, IMAC and ACCLAIM double-blind, placebo-controlled studies had neutral or negative effects on outcomes of patients with HF. In the present review, we focus on the role of inflammation in pathogenesis and progression of the HF, the value of pro-inflammatory cytokines as biomarkers and the potential therapeutic applications of immunomodulation in HF patients. 相似文献
69.
Papanikolaou IS Adler A Wegener K Al-Abadi H Dürr A Koch M Pohl H Abou-Rebyeh H Veltzke-Schlieker W Wiedenmann B Rösch T 《European journal of gastroenterology & hepatology》2008,20(4):342-348
OBJECTIVES: Endoscopic ultrasonography (EUS) with the adjunct of EUS-guided fine needle aspiration has become an important diagnostic modality in gastroenterologic oncology. EUS-guided fine needle aspiration mainly relies on cytology; data are scarce that compare cytology and histology. While testing a 22-gauge prototype needle, we prospectively compared the yield for both. METHODS: Forty-two consecutive patients (27 male, 15 female; mean age 59.2 years, range: 17-90 years) were included. In each patient we aimed to make two needle passes, and if the material acquired appeared insufficient macroscopically (no in-room cytopathology was available), further passes were done. The material was sent for cytological and histological assessment. RESULTS: A median number of two passes (range: 2-3) were uneventfully performed for pancreatic lesions (n=30), mediastinal and other lymph nodes/masses (n=8) and various other lesions (n=4) and yielded adequate material for cytology, histology or at least one of the two investigations in 62, 67 and 74% of patients, respectively. No false positive results were found (specificity 100%). Sensitivities were 58.6 and 65.5%, respectively, for cytology and histology alone; combined assessment increased sensitivity to 79.3%. When adjusted values were calculated, based only on those cases with adequate material, sensitivity was 89.5% for cytology and 85.7% for histology, and increased to 100% with combined assessment. CONCLUSION: The new needle achieves sensitivities similar to those previously reported with no significant differences in sensitivity between cytology and histology. More effective tissue acquisition methods must be sought to improve overall results. 相似文献