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981.
OBJECTIVES: The main components of protein C anticoagulant system are protein C (PC), protein S (PS) and thrombomodulin (TM); the system plays a protective role in pregnancy, mainly because it prevents the utero-placental circulation from local thrombosis. It is unknown whether the protein C anticoagulant pathway exists in amniotic fluid. The aim of the present study is to find out whether these three components are present in amniotic fluid. STUDY DESIGN: The study group consisted of 50 parturients with an uneventful pregnancy and birth and 25 non-pregnant controls. Amniotic fluid and blood were sampled at the end of the 1st stage of labor. PC, PS and TM were measured by immunoenzymatic method. RESULTS: All the samples of amniotic fluid contained measurable amounts of antigens of PC, PS and TM, although their concentrations were significantly lower than in the mother's blood: (i) The concentration of PC in amniotic fluid was 6.24+/-3.50% and PS 2.40+/-1.64%, while in the mothers' plasma it was 138.26+/-12.38% and 93.15+/-13.24%, respectively (P<0.0001). (ii) TM concentration in amniotic fluid constituted 63.92% of the concentration in the mother's blood (2.71+/-1.21 ng/mL vs. 4.24+/-0.88 ng/mL, P<0.001). CONCLUSION: Protein C, protein S and thrombomodulin are physiological constituents of the amniotic fluid. As their concentrations are low, it is reasonable to assume that they cannot counterbalance the procoagulant activity of amniotic fluid.  相似文献   
982.
983.
Kynurenic acid is an antagonist of ionotropic glutamate receptors. It has been found that glutamate antagonists inhibit proliferation of different human tumor cells. Since the hyperplasia of synovial fibroblasts is one of the most striking features of inflammatory arthritis, the main goals of this study were detection and quantification of kynurenic acid in synovial fluid obtained from patients with rheumatoid arthritis, and determination of its effect on proliferation of synoviocytes in vitro. Presence of kynurenic acid was determined by HPLC in all 58 samples of synovial fluid. The mean concentration was 15.89 pmol/ml. Kynurenic acid inhibited synoviocyte proliferation with the IC50 value of 5.9 mM. In subthreshold concentration of 0.3 mM it enhanced antiproliferative action of celecoxib and nimesulide. In conclusion, the presence of kynurenic acid in synovial fluid was documented in patients with rheumatoid arthritis. Its potential role as an endogenous substance, controlling synoviocyte proliferation can be suggested.  相似文献   
984.
Slime production is a very important factor related to biofilm formation. The objective of the present study was to determine the frequency of slime production by Staphylococcus aureus and Staphylococcus epidermidis strains recovered from 50 patients with diabetic foot ulcers. Slime production was determined using the Congo red agar (CRA) method and compared with immunocytochemistry for the production of polysaccharide intercellular adhesin (PIA). Out of 55 S. aureus strains, 69% produced slime as shown by the CRA method. Of them, 84.2% also produced PIA. Of 17 CRA-negative strains, 70.6% produced PIA. Out of 20 S. epidermidis strains, 75% were CRA positive and 93.3% produced PIA. All CRA-negative S. epidermidis produced PIA. In conclusion, PIA production is a very common trait of S. aureus and S. epidermidis isolates obtained from diabetic foot ulcer patients.  相似文献   
985.
Head and neck squamous cell carcinoma (HNSCC) has a relatively high mortality rate and poor prognosis. Recently, we showed that overexpression of phosphorylated (p) nuclear factor-kappaB (NF-kappaB) in squamous cell carcinoma of the tonsil (SCCT) and high grade dysplasia is associated with a poor prognosis. Because the mammalian target of the rapamycin (mTOR) pathway contributes to the activation of NF-kappaB through immunophilin/mTOR signaling, we investigated: (a) the immunohistochemical expression and state of activation and potential clinical significance of components of the mTOR signal transduction pathway in SCCT patients (morphoproteomics); and (b) the inhibitory effects of rapamycin on the growth and state of activation of mTOR in 2 HNSCC cell lines (pharmacoproteomics). Archival biopsy materials from 39 patients with SCCT were studied by immunohistochemistry for the expression of p-mTOR (Ser 2448), and p-p70S6K (Thr 389), and/or cyclin D1. Results for SCCT were compared with adjacent non-neoplastic epithelium, when present, and with normal tonsillar epithelium from approximately age-matched controls; clinical outcomes were also assessed. SCCT showed mTOR (Ser 2448) expression in 93% (30/32 cases) with 2+ or 3+ plasmalemmal and/or cytoplasmic intensity in 84% vs 42% in surface epithelium from normal tonsils (p <0.001). The mean combined expression score (signal intensity x percentage of positive cells) for p-p70S6K was significantly greater in the SCCT group vs adjacent non-neoplastic squamous epithelium and normal tonsillar epithelium of the control group (p <0.05). A relationship existed between higher p-p70S6K expression levels in the non-neoplastic squamous epithelium adjacent to the SCCT and increased risk of death from disease (hazard ratio = 7.9; 95% confidence interval (CI) = 2.1 to 29.9; p = 0.002). There was also a relationship between nuclear expression of cyclin D1 in SCCT and shortened recurrence-free survival (p = 0.015). Two human HNSCC cell lines, SCC-15 and FaDu, were incubated with and without rapamycin to assess its impact on growth and on the expression of p-mTOR. Rapamycin in a dose-dependent fashion inhibited growth more in SCC-15, which correlated with a greater reduction in constitutively activated p-mTOR (Ser 2448) as shown by Western blotting. In conclusion, these morphoproteomic and pharmacoproteomic data collectively provide a rationale for selecting mTOR effectors as therapeutic targets in HNSCC.  相似文献   
986.
The authors present the current views on the use of electrical stimulation in selected movement disorders (Parkinson's disease, dystonia) and pain syndromes (central and neuropathic pain) refractory to pharmacological therapy. Stimulation should be applied in cases with an established diagnosis (especially Parkinson's disease and dystonia) and with a lack of efficacy despite the best available medical therapy. Therefore it should be the last treatment option, except of generalized dystonia, where it seems to be nowadays the treatment of choice. Suggested selection criteria are based on experience of different centers and on current medical literature. They are published to make the procedure more rational and more available in Poland.  相似文献   
987.
The synthesis of the NMDA receptor glycine site antagonist kynurenic acid (KYNA) from exogenously added kynurenine was measured in cultured cerebral cortical neurons, cortical astrocytes and an oligodendroglial cell line OLN-93, incubated for 2 h in the presence or absence of ammonium acetate ("ammonia") at 0.1-10 mM concentration. In neurons ammonia stimulated KYNA synthesis to approximately 160-170% of control at 0.1-1.0mM, did not produce any effect at 2.5 and 5 mM, and inhibited the synthesis to approximately 80% of control at 10mM concentration. In astrocytes, a stimulation to approximately 200% of control occurred in the whole ammonia concentration range. No effect of ammonia was noted in OLN-93 cells. Increased KYNA synthesis may represent a cytoprotective response of astrocytes and neurons against the NMDA receptor-mediated cytotoxic activity of ammonia.  相似文献   
988.
BACKGROUND/AIMS: The presence of executive impairment in mild Alzheimer's disease (AD) has primarily been demonstrated by means of group comparison. Whether executive dysfunction is a common feature of mild AD or only present in a subgroup of patients remains unclear. The aim of this study was to describe the frequency of impairment on a set of internationally well-known executive tests in patients with very mild AD. METHODS: Thirty-six patients with very mild AD (MMSE scores above 23) and 32 healthy control subjects were administered a battery of 7 executive tests: Trail Making part B, Stroop Interference Test, modified Wisconsin Card Sorting Test (WCST), category- and letter-based verbal fluency, a design fluency task and the Similarities subtest from WAIS. Impairment was defined as a score of 2 SD or more below control means. RESULTS: Executive impairment on at least 1 measure was seen in 76% of the patients, and 50% were impaired on 2 or more tests. Trail Making B and Stroop Interference Test were impaired in more than 40%, whereas only few patients were impaired on Similarities, WCST and design fluency. A wide variation of executive test profiles was seen among the patients. CONCLUSION: Executive impairments are common in early AD and not just a feature characteristic of a subgroup of patients. Complex attentional skills are more frequently affected than other executive functions. There is, however, considerable heterogeneity among AD patients in the pattern of executive dysfunction.  相似文献   
989.
Background: Platelet rich plasma procedure (PRP) is considered to be one of the safest aesthetic procedures. Adverse reactions after PRP administration are extreme rare. Purpose: We present the patient with serum sickness disease (SSD) after PRP procedure. Objective and methods: 41 years old female suffers from alopecia areata for 5 years with frequent relapses and she has been suffering from Menier's disease recurrent symptoms for 6 years. The patient developed SSD after third PRP rejuvenating procedure and she has also noticed new alopecia areata lesions, but without Menier's disease symptoms. After SSD, 4 months later, she developed severe symptoms of Menier's disease with an episode of sudden sensorineural hearing loss. It alleviated only after intravenous administration of methylprednisolone. In our opinion, significant contraindication of PRP procedure is an autoimmune disease in the active phase.  相似文献   
990.
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