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31.
Antibodies executing catalytic activity are referred to as antibody enzymes or short “abzymes” and may have diagnostic relevance. Abzymes with deoxyribonuclease (DNase) activity have been demonstrated in patients with autoimmune and infectious diseases. Despite several reports on the occurrence of DNase abzymes in systemic autoimmune rheumatic diseases, conclusive data about DNase activity of antibodies in patients with spondyloarthritides (SpAs) are lacking. In recent cross-sectional studies evaluating levels of IgG DNase activity in patients with psoriatic arthritis (PsA), reactive arthritis (ReA), and ankylosing spondylitis (AS), DNase activity of IgG has been assessed by the rivanol clot method and confirmed by agarose gel electrophoresis. Remarkably, levels of IgG DNase activity were significantly higher in sera of SpA patients than those in control subjects. In patients with PsA, ReA, and AS, a positive correlation of DNase IgG activity with synovitis, disease activity, and stage of spondylitis was observed, respectively. Given the involvement of autoimmune reactions in cytolysis and connective tissue degradation in PsA, ReA, and to a lesser extent in AS, abzymes might have an impact on the pathophysiology of SpAs. Detection of IgG DNase activity in patients suffering from SpA represents an exciting new research field and may assist in the differential diagnosis of SpA.  相似文献   
32.

Objective

To set up the minimal conditions necessary to ensure that the social and familial network of the patient is preserved during the hospital stay for allogeneic hematopoïetic stem cell transplantation.

Material and methods

A national survey was conducted to increase knowledge about the conditions of hospital stay of adult and pediatric stem cell recipients. Then a multidisciplinary panel of health workers including doctors and nurses met to establish recommendations for maintaining the social and familial relationships optimally during the HSCT procedure.

Results

Practices and policies are very heterogeneous among the transplant centers. No consensus has been established and the literature data are scarce. The panel has thus established a list of recommendations to maintain optimal relationships between the patient and his relatives and friends during the hospital stay. The objective is to ensure a better acceptation of the isolation conditions and to facilitate the return home after D30.

Conclusion

Since there is no established scientific background for drastic isolation conditions, a multi-disciplinary approach in relationship with patients associations should allow softening of the procedures without impairing the quality of care.  相似文献   
33.
Novel biorenewable copolymer thermosets are successfully synthesized by the ring‐opening metathesis polymerization (ROMP) of norbornenyl‐functionalized castor oil (NCO) and norbornenyl‐functionalized castor oil alcohol (NCA) with controlled amounts of 0.8 and 1.8 norbornene rings per fatty acid chain, respectively. The NCO and NCA monomers are mixed in different concentrations and simultaneously polymerized via ROMP using Grubbs catalyst. Broadband dielectric relaxation spectroscopy (BDRS) is used to investigate the molecular dynamics of the fully cured copolymer thermosets over a wide range of frequencies (5 × 10?2 to 0.5 × 107 Hz) at different constant temperatures (?70 to 125 °C). Four phenomena, namely α‐, β‐, and γ‐relaxation processes and ionic conductivity are observed for all the measured samples.

  相似文献   

34.
Marine organisms have been considered an interesting target for the discovery of different classes of secondary natural products with wide-ranging biological activities. Sponges which belong to the order Dictyoceratida are distinctly classified into 5 families: Dysideidae, Irciniidae, Spongiidae, Thorectidae, and Verticilliitidae. In this review, compounds isolated from Dictyoceratida sponges were discussed with their biological potential within the period 2013 to December 2019. Moreover, analysis of the physicochemical properties of these marine natural products was investigated and the results showed that 78% of the compounds have oral bioavailability potential. This review highlights sponges of the order Dictyoceratida as exciting source for discovery of new drug leads.

Marine organisms have been considered an interesting target for the discovery of different classes of secondary natural products with wide-ranging biological activities.  相似文献   
35.

Background and study aims

Central nervous system (CNS) involvement in hepatitis C virus (HCV) infection has different facets such as anxiety, depression, cognitive impairment and vasculitis. We were interested in detecting subclinical CNS involvement in chronic HCV infected subjects with and without systemic vasculitis.

Patients and methods

Nineteen patients (15 females and 4 males) with chronic HCV infection (mean age 46.5?±?7 and mean duration since diagnosis of HCV infection 4.7?±?4?years, including 6 (32%) Child-Pugh class A cirrhotic patients) and 30 age, sex and education matched healthy control subjects were studied. Thirteen patients had associated vasculitis. Patients and control subjects were assessed using the block design and comprehension subtests of Wechsler Bellevue Adult Intelligence Scale, Wechsler Memory scale (WMS), Beck Anxiety Inventory (BAI) and Beck Depression Inventory (BDI). Brain HMPAO Single Photon Emission Computed Tomography (SPECT) was performed for HCV patients.

Results

Patients with HCV had lower scores on the block design test compared to control subjects (8.37?±?1.89 versus 10.37?±?1.47, p?<?0.001), lower total WMS scores (43.15?±?10.49 versus 60.27?±?8.08, p?<?0.001) and higher anxiety and depression scores (16.94?±?10.46 and 37.17?±?10.38 versus 10.3?±?4.67 and 28.9?±?5.99, p?=?0.004 and 0.001, respectively). Total WMS were lower in HCV patients with vasculitis compared to those without vasculitis (39.14?±?9.3 versus 51.17?±?8.3, p?=?0.019) while the block design and comprehension tests, BAI and BDI were not significantly different between both groups. The block design and comprehension tests, WMS, BAI and BDI were not significantly different between cirrhotic and non-cirrhotic patients. Seven patients had different patterns of cerebral hypoperfusion on SPECT, and all of them had associated vasculitis. Abnormal SPECT was associated with lower total WMS scores (35.87?±?10.8 versus 46.79?±?8.6 in those with normal SPECT, p?=?0.049).

Conclusions

Vasculitis may contribute to the development of neuropsychiatric involvement in HCV patients.  相似文献   
36.
Hypertension is twice as common in patients with diabetes compared to those without diabetes. It accounts for up to 75% of cardiovascular disease risk leading to the substantial increase in morbidity and mortality. Control of blood pressure in people with diabetes has been shown in randomized controlled trials to decrease cardiovascular risk and improve outcome especially in preventing stroke. A target blood pressure goal of <130/80 mm Hg is currently recommended for patients with diabetes. However, less than 1/3 of these patients achieve such a goal. This is in part due to the inherent difficulty in controlling blood pressure in these patients where hypertension is usually associated with increased salt sensitivity, volume expansion and isolated systolic hypertension. Therefore, patients with diabetes usually require multiple medications for optimal blood pressure control. Calcium channel antagonists have been shown in large clinical trials to be both safe and effective in controlling blood pressure in diabetic patients and will continue to play a major role in the management of hypertension in this population, particularly in the combination therapy that these patients usually require.  相似文献   
37.
Due to its profound therapeutic consequences, the distinction between thymoma and T-lymphoblastic lymphoma in needle biopsies is one of the most challenging in mediastinal pathology. One essential diagnostic criterion favouring thymoma is the demonstration of increased numbers of keratin-positive epithelial cells by immunohistochemistry. Loss of keratin expression in neoplastic epithelial cells could lead to detrimental misdiagnoses. We here describe a series of 14 thymic epithelial tumours (11 type B2 and B3 thymomas, 3 thymic carcinomas) with loss of expression of one or more keratins. Cases were analysed for expression of various keratins and desmosomal proteins by immunohistochemistry and immunofluorescence and compared with 45 unselected type B thymomas and 24 thymic carcinomas arranged in a multitissue histological array. All 14 cases showed highly reduced expression of at least one keratin, three cases were completely negative for all keratins studied. Of the 14 cases, 13 showed strong nuclear expression of p63. Expression of desmosomal proteins was preserved, suggesting intact cell contact structures. Loss of expression of broad-spectrum-keratins and K19 was observed in 3 and 5 % of unselected thymomas and in 30 and 60 % of thymic carcinomas. A proportion of keratin-depleted thymomas contained giant cells, reminiscent of thymic nurse cells. Loss of keratin expression in type B2 and B3 thymomas is an important diagnostic pitfall in the differential diagnosis with T-lymphoblastic lymphoma and can be expected in 5 % of cases. A panel of epithelial markers including p63 is warranted to ensure correct diagnosis of keratin-negative mediastinal tumours.  相似文献   
38.
The feasibility and potential for the morphological and hemodynamic investigation of the heart has been increasing the use of the echocardiography in the research setting. Additionally, the development of new technologies, like the real time 3D echocardiography and speckle tracking, demands validation throughout experimental studies before being instituted in the clinical setting.This paper aims to provide information concerning the particularities of the echocardiographic examination in quadruped mammals, targeting the experimental research.  相似文献   
39.
40.
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