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11.
The aim of this study was to explore the complications related to Hickman-Broviac central venous catheters (Hickman-Broviac CVCs) in children with cancer, their incidence, and possible associations of complications and premature removal of CVCs with a number of risk factors. During the study period (1 Jan 2000-31 Dec 2003), 223 CVCs were inserted in 198 children (117 boys, 81 girls) at a mean age of 5.73 years (95% CI 5.19-6.27, SE 0.275). In total, 76 (38.4%) children suffered from solid tumors and 122 (61.6%) from leukemia. The mean follow-up after CVC insertion was 232.5 days (95% CI 214.9-250.2, SE 8.94) for a total of 51,839 catheter-days. A complication occurred in 20.8% of them and in 9.6% the complication led to the removal of the catheter. The most frequent complications were infection (63.9%), obstruction (26.2%), accidental failure (8.2%), and rupture (1.6%). An overall incidence of 1.17 (0.38 and 0.79 for mechanical complication and infection, respectively) per 1000 catheter days for the development of a complication was recorded. Additionally, the study revealed more nonelective removals in cases of leukemia compared to those of solid tumors. Systemic use of CVC does not appear to increase significantly the number of complications, and thus CVC remains an effective and safe tool for the management of childhood malignancies.  相似文献   
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Introduction: Cardiovascular (CV) events, as a result of accelerated atherosclerosis, are an important cause of mortality in patients with Systemic lupus erythematosus (SLE). The etiology of SLE is multifactorial and still unclear; among other potential culprits, excessive B cell activation seems to play a crucial role. Accumulating evidence supports a contributory role of B cells in the pathogenesis of atherosclerosis as well.

Areas covered: This article focuses on the contribution of both B cells and autoantibodies in the pathogenesis of atherosclerosis in both general and lupus populations. Review of the published literature on experimental models has also been performed.

Expert opinion: Distinct B cell subsets seem to exhibit separate effects on the progression of atherosclerosis, with B2 B cells displaying a mainly atherogenic phenotype, while B1 B cells are mostly viewed as atheroprotective. Selective B2 inhibition by anti-B cell therapies seems a promising therapeutic strategy against atherosclerosis development in the setting of lupus.  相似文献   

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BACKGROUND: The current study sought to delineate prospectively the rates and clinical course of emotional distress, cognitive impairment, and quality of life (QOL) in chemotherapy-naive patients with cancer and to consider the determinants of global QOL. METHODS: Patients who consented to participate were administered the European Organization for Research and Treatment of Cancer QLQ-C30 questionnaire, the Mini-Mental State Examination (MMSE), and the Hospital Anxiety and Depression Scale before and at the end of treatment (EOT). RESULTS: Of the 102 patients initially assessed, 80 (78.4%) completed the study. Most aspects of QOL did not change considerably over time. At EOT, patients reported only significant increases in fatigue and significant decreases in sleep disturbance. Although no significant changes emerged in the rates of anxiety or depression throughout chemotherapy, nearly one-third of the patients experienced severe emotional distress at both points in time. In addition, the authors observed neither significant alteration in the cognitive performance over time nor reliable associations between scores on the MMSE and subjective cognitive function, emotional distress, or QOL. Finally, depression proved to be the leading predictor of global QOL at baseline and at EOT. CONCLUSIONS: The results indicated that a significant proportion of Greek patients with cancer experienced intense anxiety and depression throughout chemotherapy and confirmed the importance of depression as a strong predictor of global QOL. Routine screening of emotional distress across all phases of cancer is mandatory because it will contribute to the identification of patients who are in need of pharmaceutical and/or psychologic intervention.  相似文献   
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Cystinosis is an autosomal recessive disorder associated with excessive lysosomal cystine accumulation secondary to defective lysosomal cystine efflux. CTNS, the gene mutated in cystinosis, codes for the lysosomal membrane protein cystinosin. Antisera were raised in rabbits to a carboxy-terminal oligopeptide sequence from cystinosin. Antisera were screened by Western blotting and immunocytochemical analyses of transfected COS-7 cells expressing either human wild-type cystinosin, a wild-type cystinosin-green fluorescent protein (GFP) fusion protein, or a fusion protein of GFP and mutant human cystinosin with a carboxy-terminal deletion. In Western blots, bands corresponding to cystinosin or cystinosin-GFP were observed in transfected cells but no signal was detected in cells expressing the carboxy-terminal mutant; preimmune sera yielded negative results in all three cases. In transfected cells expressing wild-type cystinosin, immunoreactivity appeared in subcellular vesicles. In cells expressing the wild-type cystinosin-GFP fusion protein, immunoreactivity colocalized with GFP fluorescence. Previous studies demonstrated that GFP fluorescence from this construct colocalized with immunostaining for a known lysosomal membrane protein, i.e., lysosome-associated membrane protein 2. In immunohistochemical analyses, cystinosin localized to tubule epithelia in three normal human kidneys, with a pattern similar to that of lysosome-associated membrane protein 2; cystinosin immunoreactivity was absent in kidneys from patients with a CTNS deletion. For the first time, antisera have been raised that localize cystinosin in cells in vitro and in vivo.  相似文献   
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BACKGROUND: Recent studies have shown that the odds ratio for high-sensitivity C-reactive protein (CRP) in predicting a coronary events in healthy subjects is 1.4, a value substantially less than previously reported. It is unclear whether this extends to acute coronary syndrome patients or if CRP would predict long-term events in this population. We evaluated the predictive value of CRP in patients with non-ST segment elevation myocardial infarction (NSTEMI) as their first manifestation of coronary artery disease and compared it with that of left ventricle diastolic function. METHODS: Serum CRP concentration measurement and left ventricle diastolic function evaluation were performed in 51 consecutive patients with NSTEMI 48 hours, 3 months, and 6 months after infarction. Patients were followed for 1 year and events comprising the endpoints of death, new myocardial infarction, percutaneous coronary intervention, and coronary artery bypass grafting were reported. RESULTS: Thirty of 51 patients developed the endpoints. Mean CRP concentration in patients who developed any endpoint and those who did not was similar at 48 hours, 3 months, and 6 months. A strong correlation between the presence of impaired relaxation 6 months after the infarction and development of the combined endpoints was noted (P < 0.001). CONCLUSION: CRP has limited value in predicting future cardiovascular events in subjects with NSTEMI. Other biomarkers or a combination of other biomarkers may be needed to identify patients at high risk. Evaluation of diastolic left ventricular function not during the acute phase but 6 months later could predict adverse outcome in our series.  相似文献   
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BACKGROUND: The prevalence of thrombophilic traits, which might further enhance the risk of thrombotic complications in children treated for cancer, varies significantly among different populations. OBJECTIVE: To evaluate the prevalence of common thrombophilic traits of the East Mediterranean Region, among native Cretan children treated for malignancy. METHODS: Blood samples were consecutively collected from 31 native Cretan children treated for acute lymphoblastic leukaemia (n = 19) or other malignancies (n = 12) over 3 years. A molecular diagnosis based on the presence of Factor V Leiden (FVL), as well as on PT G20210A and MTHFR C677T mutation (in 14 patients) using PCR was applied. Patients who had central venous catheters (n = 29) were treated with an intensified thromboprophylaxis protocol that had been previously established in our institution. RESULTS: The prevalence of the FVL mutation was 19.4% (95% CI = 5-32). The allele frequency is estimated at 11.3% (95% CI: 3.5-19.1) which is higher than that reported for the population of the mainland of Greece. The prevalence of the PT G20210A and MTHFR C677T mutation was 14.3 and 71.4%, respectively (corresponding allele frequencies 7.1 and 50%, respectively). Only one patient developed thrombosis, having although no thrombophilic trait. CONCLUSIONS: Thrombophilic traits were relatively common in this group of native Cretan children treated for malignancy. Thromboprophylaxis should be considered in Cretan children in the presence of known acquired risk factors for thrombosis, but a larger prospective to study is first needed.  相似文献   
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OBJECTIVES: (a) To measure the absorbed dose at certain anatomical sites of a RANDO phantom and to estimate the effective dose in radiographic imaging of the jaws using low dose Cone Beam computed tomography (CBCT) and (b) to compare the absorbed and the effective doses between thyroid and cervical spine shielding and non-shielding techniques. STUDY DESIGN: Thermoluminescent dosimeters (TLD-100) were placed at 14 sites in a RANDO phantom, using a Cone Beam CT device (Newtom, Model QR-DVT 9000, Verona, Italy). Dosimetry was carried out applying two techniques: in the first, there was no shielding device used while in the second one, a shielding device (EUREKA!, TRIX) was applied for protection of the thyroid gland and the cervical spine. Effective dose was estimated according to ICRP(60) report (E(ICRP)). An additional estimation of the effective dose was accomplished including the doses of the salivary glands (E(SAL)). A Wilcoxon Signed Ranks Test was used for statistical analysis. RESULTS: In the non-shielding technique the absorbed doses ranged from 0.16 to 1.67 mGy, while 0.32 and 1.28 mGy were the doses to the thyroid and the cervical spine, respectively. The effective dose, E(ICRP), was 0.035 mSv and the E(SAL) was 0.064 mSv. In the shielding technique, the absorbed doses ranged from 0.09 to 1.64 mGy, while 0.18 and 0.95 mGy were the respective values for the thyroid and the cervical spine. The effective dose, E(ICRP), was 0.023 mSv and E(SAL) was 0.052 mSv. CONCLUSIONS: The use of CBCT for maxillofacial imaging results in a reduced absorbed and effective dose. The use of lead shielding leads to a further reduction of the absorbed doses of thyroid and cervical spine, as well as the effective dose.  相似文献   
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