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1.
Background There is limited information about the clinical characteristics, treatment and outcome of maintenance hemodialysis patients with COVID-19. Moreover, regional differences are also conceivable since the extend and severity of outbreaks varied among countries.Methods In this retrospective, observational, single-center study, we analyzed the clinical course and outcomes of 37 maintenance hemodialysis patients (median age 64 years, 51% men) hospitalized with COVID-19 from 24 March to 22 May 2020 as confirmed by real-time PCR.Results The most common symptoms at admission were fatigue (51%), fever (43%), dyspnea (38%) and cough (35%). There were 59% mild/moderate patients and 41% severe/critical patients. Patients in the severe/critical group had a significantly higher atherosclerotic burden since diabetic kidney disease and vascular nephropathies were the most common primary kidney diseases and eighty percent of them had coronary heart disease. Also, Charlson comorbidity score was higher in this group. At admission chest X-ray, 46% had ground-glass abnormalities. Overall, 60% patients received hydroxychloroquine, 22% lopinavir–ritonavir, 11% tocilizumab, 24% systemic glucocorticoids, and 54% received prophylactic anticoagulation. Seven (19%) patients died during hospitalization and 30 were discharged. The main causes of death were cardiovascular (5 patients) and respiratory distress syndrome (2 patients). In Cox regression analysis, lower oxygen saturation, anemia and hypoalbuminemia at admission were associated with increased mortality.Conclusions In conclusion, we observed a high mortality rate among maintenance hemodialysis patients hospitalized for COVID-19. Anemia, lower serum albumin and lower basal oxygen saturation at admission were factors associated with poor prognosis.  相似文献   
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Introduction: We followed patients with pulmonary arterial hypertension (PAH) receiving specific vasodilator therapy and tested for predictors of clinical outcome. Methods: Thirty‐two patients (mean age 39 ± 15 years, 22 women, diagnosed with pulmonary hypertension; PH): 29 with PAH and 3 patients with inoperable chronic thromboembolic PH received therapy with either bosentan, sildenafil, or both and were evaluated with clinical parameters, biomarkers (B‐type natriuretic peptide values), and echocardiography before receiving specific medication and every 3 months thereafter. A right heart catheterization was performed at baseline. A composite endpoint of death, worsening of functional class, or the need of a second vasodilator agent was used to define the clinical nonresponders. Results: Patients were followed for 14 months (7.5–21). The endpoint was reached by 15 patients: four patients died (two idiopathic PAH and two PAH in context of Eisenmenger syndrome), seven patients showed 1 functional class worsening, and four patients needed to be switched to combination therapy. Patients who remained clinically stable or improved had at baseline a better cardiac output with a less remodeled right ventricle (RV) and better functioning RV (all P < 0.05). A RV fractional area change (RVFAC) lower than 25.7% and a RV global strain value higher than ?13.4% predict with 87% sensitivity and 83% specificity (AUC 87.3%, P = 0.001) and 73% sensitivity and 91% specificity (AUC 84.2%, P = 0.003), respectively, patients who will deteriorate clinically under specific vasodilator therapy. A multivariate model showed RVFAC to be the only independent predictor of the endpoint with a HR of 0.87 (0.8–0.96), P = 0.007. Conclusions: Over an average period of 1 year, almost half of patients showed signs of clinical deterioration despite specific vasodilator therapy. Parameters of right ventricular morphology and function had prognostic value in these patients.  相似文献   
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This study aimed to evaluate by immunohistochemistry and transmission electron microscopy (TEM) the morphological features of the oral mucosa endothelial tip cells (ETCs) and to determine the immune and ultrastructural patterns of the stromal nonimmune cells which could influence healing processes. Immune labeling was performed on bioptic samples obtained from six edentulous patients undergoing surgery for dental implants placement; three normal samples were collected from patients prior to the extraction of the third mandibular molar. The antibodies were tested for CD34, CD117(c‐kit), platelet derived growth factor receptor‐alpha (PDGFR‐α), Mast Cell Tryptase, CD44, vimentin, CD45, CD105, alpha‐smooth muscle actin, FGF2, Ki67. In light microscopy, while stromal cells (StrCs) of the reparatory and normal oral mucosa, with a fibroblastic appearance, were found positive for a CD34/CD44/CD45/CD105/PDGFR‐α/vimentin immune phenotype, the CD117/c‐kit labeling led to a positive stromal reaction only in the reparatory mucosa. In TEM, non‐immune StrCs presenting particular ultrastructural features were identified as circulating fibrocytes (CFCs). Within the lamina propria CFCs were in close contact with ETCs. Long processes of the ETCs were moniliform, and hook‐like collaterals were arising from the dilated segments, suggestive for a different stage migration. Maintenance and healing of oral mucosa are so supported by extensive processes of angiogenesis, guided by ETCs that, in turn, are influenced by the CFCs that populate the stromal compartment both in normal and reparatory states. Therefore, CFCs could be targeted by specific therapies, with pro‐ or anti‐angiogenic purposes. Anat Rec, 2013. © 2012 Wiley Periodicals, Inc.  相似文献   
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ABSTRACT: BACKGROUND: A tenth of patients with involuntary weight loss (IWL) have gastrointestinal cancer. Ferritin is the first parameter to be modified during the process leading to iron deficiency anaemia, therefore it should be the most sensitive. The aim of this study was to assess the ability of ferritin to rule out gastrointestinal cancer in patients with involuntary weight loss. METHODS: All consecutive patients with IWL admitted in a secondary care university hospital were prospectively studied. Ferritin, haemoglobin with erythrocyte indices and serum iron were recorded for all patients. The reference standard was bidirectional endoscopy and/or 6 months follow-up. RESULTS: 290 patients were included, a quarter had cancer, of which 22 (7.6%) had gastrointestinal cancer (8 gastric cancer, 1 ileum cancer, 13 colorectal cancer). Ferritin had the best area under the curve (AUC), both for gastrointestinal cancer (0.746, CI: 0.691-0.794), and colorectal cancer (0.765, CI: 0.713-0.813), compared to the other parameters of iron deficiency. In the diagnosis of colorectal cancer, ferritin with a cut-off value of 100 mcg/L had a sensitivity of 93% (CI: 69-100%), and negative likelihood ratio of 0.13, with a negative predictive value of 99% (96-100%), while for gastrointestinal cancer, the sensitivity was lower (89%, CI: 67-95%), with a negative likelihood ratio of 0.24. There were three false negative patients, two with gastric cancer, and one with rectal cancer. CONCLUSION: In patients with involuntary weight loss, a ferritin above 100mcg/L could rule out colon cancer, but not gastric or rectal cancer.  相似文献   
6.
In Canada, hydroxyethyl starch 264/0.45 (HES 264/0.45; molar weight 264 kDa, molar substitution 0.45) has largely replaced albumin as the colloidal fluid of choice for perioperative intravascular volume expansion. The maximum recommended dose of HES 264/0.45 is 28 mL/kg; however, there are no clinical data supporting this limit. In this study we compared the hemostatic effects of HES 264/0.45 versus 5% albumin in doses up to 45 mL/kg over 24 h during major reconstructive head and neck surgery. Fifty patients were randomized to receive HES 264/0.45 or 5% human albumin from the induction of anesthesia until 24 h thereafter. Both albumin and HES 264/0.45 effectively maintained physiologic variables in the perioperative and postoperative periods. The partial thromboplastin time and international normalized ratio were significantly increased in the HES 264/0.45 group compared with the albumin group after infusion of 30 mL/kg and 45 mL/kg (P < 0.05). Factor VIII activity and von Willebrand factor level were significantly reduced in the HES 264/0.45 group compared with the albumin group after infusion of 15 mL/kg, 30 mL/kg, and 45 mL/kg (P < 0.05). Significantly more subjects in the HES 264/0.45 group received allogeneic red blood cell transfusions (P < 0.02). We conclude that HES 264/0.45 infusions >30 mL/kg over 24 h impair coagulation to a greater extent than albumin, possibly leading to more allogeneic transfusions.  相似文献   
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There are no clear recommendations regarding cirrhotic cardiomyopathy (CC) evaluation in patients with pre-transplant liver cirrhosis. The roles of new methods, tissue Doppler imaging (TDI) and speckle tracking echocardiography (STE) in the diagnosis and prognosis of cirrhotic cardiomyopathy remain controversial. We investigated the utility of TDI/STE parameters in cirrhotic cardiomyopathy diagnosis and also in predicting mortality in patients with liver cirrhosis. Left/right ventricular function was studied using conventional TDI (velocities) and STE (strain/strain rate). We assessed left ventricular diastolic dysfunction, graded into four new classes (I/Ia/II/III). Serum NTproBNP (N-terminal prohormone of brain natriuretic peptide), troponin I, β-crosslaps, QTc interval, arterial compliance and endothelial function were measured. Liver-specific scores (Child–Pugh, MELD, MELDNa) were computed. There was a 1-y follow-up visit to determine mortality. We observed resting biventricular diastolic myocardial dysfunction, not presently included in the definition of cirrhotic cardiomyopathy. We provided an improved characterization of cardiac dysfunction in patients with liver cirrhosis. This might change the current definition. However, the utility of STE/TDI parameters in predicting long-term mortality in patients with liver cirrhosis remains controversial.  相似文献   
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Recent recognition of the key role of primary cilia in orchestrating human development and of the dire consequences of their dysfunction on human health has placed this small organelle in the spotlight. While the causal link between mutations in ciliary genes and central nervous system malformations and dysfunction is well established, the mechanisms by which primary cilia dysfunction acts on development and function of the CNS remain partly unknown. The recent article by Bashford and Subramanian in The Journal of Pathology describes a new mouse model for the neurodevelopmental ciliopathy Joubert syndrome, supporting a role for ciliary-mediated Hedgehog signaling on proliferation, survival, and differentiation of cerebellar granule cell progenitors. © 2019 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.  相似文献   
10.
Rajan DK  Bunston S  Misra S  Pinto R  Lok CE 《Radiology》2004,232(2):508-515
PURPOSE: To determine the primary and secondary patency rates for fistulas treated with angioplasty, as well as clinical predictors of fistula patency after angioplasty. MATERIALS AND METHODS: The authors reviewed their institutional experience with autogenous fistulas from June 1997 to June 2002. A total of 104 men and 36 women were treated. Mean age +/- standard deviation of patient cohort was 62.4 years +/- 15.6. Patient age and sex, age of fistula at initial intervention, presence of diabetes, side and location of fistula, location of stenosis, and number of venous stenoses dilated were examined. Patency after angioplasty was estimated by using the Kaplan-Meier method, and predictors of patency were examined by using a Cox proportional hazards model. RESULTS: One hundred fifty-one dysfunctional fistulas (94 radiocephalic and 57 brachiocephalic) were treated with angioplasty initially. Clinical success rate was 98.0% (297 of 303 interventions). At 3, 6, and 12 months, respectively, primary patency rates +/- standard errors of the estimate were 73% +/- 6, 51% +/- 7, and 39% +/- 7 for brachiocephalic fistulas and 85% +/- 4, 75% +/- 5, and 62% +/- 5 for radiocephalic fistulas; secondary patency rates were 96% +/- 2.4, 89% +/- 4, and 85% +/- 5 for brachiocephalic fistulas and 91% +/- 3, 88% +/- 3, and 86% +/- 4 for radiocephalic fistulas. For all time points, there was a significant difference in primary (P =.004) but not secondary (P =.45) patency between radiocephalic and brachiocephalic fistulas. Stenosis was most prevalent within 3 cm of the arteriovenous anastomosis in 74 (64%) of the 116 dysfunctional radiocephalic fistulas and at the cephalic arch in 22 (30%) of the 74 dysfunctional brachiocephalic fistulas. The clinical variables examined did not influence outcome. Complications occurred in seven (2.3%) of 303 interventions. CONCLUSION: Patency after angioplasty in dysfunctional autogenous hemodialysis fistulas exceeds that observed in hemodialysis grafts. None of the clinical or anatomic variables examined affected patency outcome.  相似文献   
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