Monte Carlo estimation of radiation doses in red bone marrow and breast in common pediatric x-ray examinations

Radiation exposure was investigated for children undergoing various common radiographies in three dedicated pediatric hospitals in Greece. Kerma in air at the entrance of the beam (Ka,e) was measured with thermoluminescent dosimeters. Ka,e values ranged from 0.09 mGy to 5.52 mGy and were found to be greater in Hospital C, because of the increased high voltage and time-current product used by the radiation technologists. Equivalent doses in red bone marrow and breast were estimated with Monte Carlo simulation by PCXMC code. Values ranged from 2 microSv to 204 microSv for red bone marrow and from 0 to 817 muSv for breast. Variation in doses occurred due to field size, high voltage setting, and Ka,e.     

Working in the sky: a diary study on work engagement among flight attendants

This study aims to gain insight in the motivational process of the Job Demands-Resources (JD-R) model by examining whether daily fluctuations in colleague support (i.e., a typical job resource) predict day-levels of job performance through self-efficacy and work engagement. Forty-four flight attendants filled in a questionnaire and a diary booklet before and after consecutive flights to three intercontinental destinations. Results of multilevel analyses revealed that colleague support had unique positive effects on self-efficacy and work engagement. Self-efficacy did not mediate the relationship between support and engagement, but work engagement mediated the relationship between self-efficacy and (in-role and extra-role) performance. In addition, colleague support had an indirect effect on in-role performance through work engagement. These findings shed light on the motivational process as outlined in the JD-R model, and suggest that colleague support is an important job resource for flight attendants helping them reach their work-related goals.     

Polymorphisms associated with apolipoprotein B levels in Greek patients with familial hypercholesterolemia.

BACKGROUND: Familial hypercholesterolemia (FH) is a genetic disorder characterized by high low-density lipoprotein-cholesterol (LDL-C) concentrations, which frequently gives rise to premature coronary artery disease. The clinical expression of FH is highly variable, even in patients carrying the same LDL receptor (LDLR) gene mutation. This variability may be due to environmental and other genetic factors. METHODS: We investigated paraoxonase 2 (PON 2) Ser311Cys, lipoprotein lipase (LPL) Asn291Ser, plasminogen activator inhibitor-1 (PAI-1) T11053G, beta-fibrinogen (FGB) -455 G>A and nitric oxide synthase gene (NOS) -922 A>G polymorphisms in 84 patients with FH. The effect of polymorphisms as independent factors of high lipid values was evaluated. RESULTS: The PON 2 Cys311 allele was correlated with high total cholesterol and LDL-C and apolipoprotein B levels, while LPL Asn291, PAI-1 T11053, FGB -455 G and NOS -922 A alleles were correlated with high apolipoprotein B levels. CONCLUSIONS: These results suggest that apolipoprotein B levels in FH heterozygotes may be affected by several different genetic variants.     

Arterial Stiffness Is Inversely Related to Plasma Adiponectin Levels in Young Normotensive Patients With Type 1 Diabetes

OBJECTIVE

This study investigated the association between arterial stiffness and plasma adiponectin in patients with type 1 diabetes.

RESEARCH DESIGN AND METHODS

Participants were normotensive patients with type 1 diabetes who were up to age 40 years. Subjects on statins with macrovascular disease or overt nephropathy were excluded. Large artery stiffness was assessed by measurement of carotid-femoral pulse wave velocity (PWV), whereas plasma adiponectin was measured by radioimmunoassay.

RESULTS

Data from 80 patients (age 27.1 ± 6.1 years, BMI 24.2 ± 3.1 kg/m², HbA_1c 7.5 ± 1.6%, 39 men, adiponectin 13.9 ± 6.7 μg/mL, and PWV 5.6 ± 0.9 m/s) were analyzed. Log adiponectin inversely correlated with age-adjusted PWV (r = −0.291, P = 0.009) and waist circumference (r = −0.427, P < 0.001). In a fully adjusted model, age, expiration/inspiration index, and log adiponectin were independently associated with PWV, explaining 39.6% of its variance.

CONCLUSIONS

Arterial stiffness is inversely related to adiponectin concentration in young patients with type 1 diabetes without major complications.Arterial stiffness, an independent predictor of total and cardiovascular mortality, can be assessed noninvasively by measurement of pulse wave velocity (PWV) (1), which is increased at early stages of type 1 diabetes (2,3). Plasma adiponectin, an adipocytokine with insulin-sensitizing, antiatherogenic, and anti-inflammatory properties (4), is high in patients with type 1 diabetes (5,6). Although adiponectin is inversely related to arterial stiffness in subjects with essential hypertension (7,8), no adiponectin-PWV relationship has been shown in children/adolescents with type 1 diabetes (9). This study investigated the association between adiponectin and PWV in young adults with type 1 diabetes.     

Assessing predictive accuracy for outcomes of ventilator-associated events in an international cohort: the EUVAE study

Purpose

To analyze the impact on patient outcome of ventilator-associated events (VAEs) as defined by the Centers for Disease Control and Prevention (CDC) in 2008, 2013, and the correlation with ventilator-associated pneumonia (VAP) or tracheobronchitis (VAT).

Methods

This was a prospective, observational, multicenter, international study conducted at 13 intensive care units (ICUs); thirty consecutive adults mechanically ventilated for ≥?48 h per site were eligible, with daily follow-up being recorded in a collaborative web database; VAEs were assessed using the 2013 CDC classification and its 2015 update.

Results

A total of 2856 ventilator days in 244 patients were analyzed, identifying 33 VAP and 51 VAT episodes; 30-day ICU mortality was significantly higher (42.8 vs. 19.6%, p?<?0.007) in patients with VAP than in those with VAT. According to the 2013 CDC definitions, 117 VAEs were identified: 113 (96%) were infection-related ventilator-associated complication-plus (IVAC-plus), while possible ventilator-associated pneumonia (PVAP) was found in 64 (56.6%) of them. VAE increased the number of ventilator days and prolonged ICU and hospital LOS (by 5, 11, and 12 days, respectively), with a trend towards increased 30-day mortality (43 vs 28%, p?=?0.06). Most episodes (26, 55%) classified as IVAC-plus without PVAP criteria were due to atelectasis. PVAP significantly increased (p?<?0.05) ventilator days as well as ICU and hospital LOS (by 10.5, 14, and 13 days, respectively). Only 24 (72.7%) of VAP and 15 (29.4%) of VAT episodes met IVAC-plus criteria.

Conclusions

Respiratory infections (mainly VAT) were the most common complication. VAE algorithms only identified events with surrogates of severe oxygenation deterioration. As a consequence, IVAC definitions missed one fourth of the episodes of VAP and three fourths of the episodes of VAT. Identifying VAT (often missed by IVAC-plus criteria) is important, as VAP and VAT have different impacts on mortality.

     

Amifostine stimulates the formation of hematopoietic bone marrow progenitors from B-cell chronic lymphocytic leukemia

Amifostine is a phosphorylated aminothiol that not only protects hematopoietic progenitor cells from chemotherapy and radiotherapy, but also stimulates normal hematopoiesis. The effect of amifostine on the in vitro growth of hematopoietic progenitors derived from B-cell chronic lymphocytic leukemia(B-CLL) was investigated. The colony-forming units (CFU)-granulocyte macrophage (CFU-GM), the burst-forming units-erythroid (BFU-E) and the CFU-granulocyte erythroid macrophage megakaryocytes (CFU-GEMM) increased 38, 20 and 100%, respectively, after the incubation with amifostine. There was no statistical difference in the in vitro progenitor growth of patients grouped according to their disease stage, bone marrow lymphocytic infiltration or therapy. Our data indicate that apart from cytoprotection the parallel use of amifostine and chemotherapy in patients with B-CLL could enhance bone marrow recovery.     

ANCA-associated glomerulonephritis/systemic vasculitis in childhood: clinical features–outcome

Background

Antineutrophil cytoplasmic antibody (ANCA)-associated glomerulonephritis and systemic vasculitis (AAGNV) is uncommon in childhood.

Methods

This is a retrospective study of AAGNV cases diagnosed over a 13-year period in a tertiary pediatric nephrology department.

Results

Thirteen cases of AAGNV were identified: seven Wegener granulomatosis (WG) and six microscopic polyangiitis (MPA). Acute renal failure/nephrotic range proteinuria (NRP) was found in 77 % of the patients (4 with WG, all with MPA). Eleven (85 %) patients showed necrotizing glomerulonephritis (NGN), with ≥50 % crescents identified in nine patients (69 %) (4 with WG, 5 with MPA). Treatment with methylprednisolone, cyclophosphamide and plasma exchange resulted in extra-renal remission and antibody reduction in all patients and renal function improvement/stabilization in 77 % of the patients. Three patients, all without oliguria at presentation and few sclerotic lesions, had normal renal function at follow-up. Chronic kidney disease (CKD) stages 2 and 3–4 were observed in four (WG) and three (MPA) patients, respectively. Three patients (23 %) developed end stage renal disease: two were MPA patients with severe presentation (markedly impaired glomerular filtration rate, oliguria, NRP, crescentic NGN, glomerular sclerosis) and one was a WG patient with extensive interstitial fibrosis/tubular atrophy.

Conclusions

Severe renal involvement was more common in children with MPA than WG. Treatment with methylprednisolone, cyclophosphamide and plasma exchange induced extra-renal remission/serological response and renal function improvement/stabilization. Markedly decreased GFR, oliguria, NRP, and chronic glomerular lesions at presentation were predictors of poor outcome.     

Elevated vWF Antigen Serum Levels Are Associated With Poor Prognosis,and Decreased Circulating ADAMTS-13 Antigen Levels Are Associated With Increased IgM Levels and Features of WM but not Increased vWF Levels in Patients With Symptomatic WM

Background

Waldenström's macroglobulinemia (WM) is a rare malignancy characterized by bone marrow infiltration by lymphoplasmacytic cells and the presence of a monoclonal IgM paraprotein. The interactions of lymphoplasmacytic cells with other cells in their microenvironment, including mast cells and endothelial cells, support their survival and proliferation and can induce resistance to therapy. von Willebrand factor (vWF) plays a key role in primary hemostasis but is also a marker of endothelial “stimulation.” High levels of vWF have been associated with an adverse prognosis in patients with symptomatic WM and might reflect the interactions between lymphoplasmacytic cells and other cells of their microenvironment.