Direct visualization of damage cascades in lithium niobate crystals caused by high-energy ions

Congruently melting undoped lithium niobate crystals are irradiated with 20 MeV (3)He ions which penetrate the entire crystal volume. Radiation damage effects are directly visualized by transmission electron microscopy (TEM) where damage zones with diameters of 4 nm give rise to circular Fresnel fringe contrasts. These regions of modified material, appearing circular in cross-section, are interpreted as damage cascades inflicted by fast Nb and O atoms displaced in knock-on collisions with primary (3)He ions. This two-step displacement process results in local density changes manifested by the contrast behaviour of Fresnel fringes observed in TEM images.

Outbreak of Salmonella enterica serovar Typhimurium in Switzerland, May – June 2008, implications for production and control of meat preparations

An increased number of Salmonella Typhimurium cases were reported in Switzerland between May and June 2008. Investigations involved 72 cases. Results of PFGE typing identified several outbreak strains, the dominating one present in 43 of the 72 isolates. Strains affecting one third of the cases were also found in animal samples, in particular pork. However, no specific food source could be identified. Outbreaks described in this paper highlight the importance of food safety regulations such as those on minced meat and meat preparations issued by the European Commission and adopted by Switzerland into the national law.

Outbreak of Salmonella enterica serovar Typhimurium in Switzerland, May-June 2008, implications for production and control of meat preparations

An increased number of Salmonella Typhimurium cases were reported in Switzerland between May and June 2008. Investigations involved 72 cases. Results of PFGE typing identified several outbreak strains, the dominating one present in 43 of the 72 isolates. Strains affecting one third of the cases were also found in animal samples, in particular pork. However, no specific food source could be identified. Outbreaks described in this paper highlight the importance of food safety regulations such as those on minced meat and meat preparations issued by the European Commission and adopted by Switzerland into the national law.

Anisotropy of antiferromagnetic 180 degrees domains in LiCoPO4 and LiNiPO4

Unexpected three-dimensional distributions of antiferromagnetic 180 degrees domains are observed in LiCoPO4 and LiNiPO4 by optical second harmonic generation. Domains in LiCoPO4 are isotropic in spite of the quasi-two-dimensional magnetic structure whereas domains in LiNiPO4 are distinctly anisotropic, but in contrast to the anisotropy of the magnetic structure. The diversity reveals a potential for fine-tuning magnetic properties determined by the distribution of domains or domain walls and the urgent need for an improved understanding of spatial correlations in antiferromagnets.

Outbreak of Salmonella serovar Stanley infections in Switzerland linked to locally produced soft cheese, September 2006 – February 2007

Salmonella serovar Stanley is rare in Europe. In Switzerland, the number of reported isolates has increased from 2 in 2000 to 25 in 2005. A nationwide outbreak of gastrointestinal illness due to S. Stanley occurred from September 2006 through February 2007. Eighty-two cases were documented. Males were 56%; mean age of the cases was 45.7 years (range 0-92). Forty-seven cases (57%) occurred in three western cantons: Vaud, Bern, and Geneva. Twenty-three cases (28%) were hospitalised. In the case-control study conducted to find the source of the outbreak, cases were more likely than controls to have eaten local soft cheese (OR 11.4, p=0.008). One clone of S. Stanley strain was isolated from soft cheese and from 77 cases (94%) who reported no history of having travelled abroad. The outbreak ended after the withdrawal of the cheese from the market. This is the first S. Stanley outbreak in Switzerland and the first in Europe unrelated to imported products, suggesting an increased local circulation of this previously rare serotype.

Potential role of fractalkine receptor expression in human renal fibrogenesis

The inhibition of several chemokine/chemokine receptors has been shown to reduce progressive renal interstitial fibrosis. In this study, we examined the expression of the CX(3)C receptor in human renal biopsies with interstitial fibrosis and from normal kidneys by real-time polymerase chain reaction (PCR) and immunohistochemistry. The CX(3)C receptor was not only detected in mononuclear, tubular epithelial, and dendritic cells but also in alpha-smooth muscle actin and vimentin-positive interstitial myofibroblasts in fibrotic kidneys. Real-time PCR indicated a significant upregulation of CX(3)C receptor mRNA in fibrotic kidneys compared with non-fibrotic nephropathies or donor biopsies. In renal fibroblasts in vitro, hydrogen peroxide increased the expression of the CX(3)C receptor, an increase that was inhibited by N-acetylcysteine and catalase. However, neither proinflammatory nor profibrotic cytokines resulted in this upregulation. Stimulation of fibroblasts by CX(3)C ligand led to a significant enhancement of migration, which was abrogated by pre-incubation with a blocking anti-CX(3)C receptor antibody. Our studies indicate that renal fibrosis is associated with the expression of CX(3)C receptors on human renal fibroblasts. The expression is induced by reactive oxygen species suggesting a role of oxidative stress.

Smoking in young people with asthma

BACKGROUND

Modern guidelines for the management of asthma state that asthmatic patients should be strongly advised not to smoke. However, it remains unclear to what extend young people with asthma actually behave like this. This study compares the prevalence of daily smoking between 15-year adolescents with diagnosed asthma and without asthma, and evaluates to what extent risk factors for smoking play a comparable role in the smoking behaviour of these two groups.

METHODS

The study is part of the 2001-2002 international HBSC study. Besides questions about health behaviour, individual and social resources, a set of asthma questions were included in six countries.

RESULTS

Adolescents with diagnosed asthma are more likely to be daily smokers than non-asthmatic adolescents. In asthmatic and non-asthmatic adolescents, similar associations with risk factors are found for daily smoking (drunkenness, cannabis use, low life satisfaction, spending evenings with friends, having smoking parents and peers). Diagnosed asthmatics are more prone to score high on these factors than non-asthmatics.

CONCLUSIONS

Smoking in adolescents with asthma is a public health problem. Smoking prevention efforts directed towards young people should pay attention to young people with asthma and the curative sector should increase their efforts to motivate asthmatic adolescents not to smoke.

Myocardial material parameter estimation: a non-homogeneous finite element study from simple shear tests

The passive material properties of myocardium play a major role in diastolic performance of the heart. In particular, the shear behaviour is thought to play an important mechanical role due to the laminar architecture of myocardium. We have previously compared a number of myocardial constitutive relations with the aim to extract their suitability for inverse material parameter estimation. The previous study assumed a homogeneous deformation. In the present study we relaxed the homogeneous assumption by implementing these laws into a finite element environment in order to obtain more realistic measures for the suitability of these laws in both their ability to fit a given set of experimental data, as well as their stability in the finite element environment. In particular, we examined five constitutive laws and compare them on the basis of (i) "goodness of fit": how well they fit a set of six shear deformation tests, (ii) "determinability": how well determined the objective function is at the optimal parameter fit, and (iii) "variability": how well determined the material parameters are over the range of experiments. Furthermore, we compared the FE results with those from the previous study.It was found that the same material law as in the previous study, the orthotropic Fung-type "Costa-Law", was the most suitable for inverse material parameter estimation for myocardium in simple shear.

Intravenous and oral sequential itraconazole antifungal prophylaxis in paediatric stem cell transplantation recipients: a pilot study for evaluation of safety and efficacy

This single-centre, retrospective, observational pilot study was performed to evaluate the safety and efficacy of intravenous and oral itraconazole prophylaxis in paediatric haematopoietic stem cell transplantation (HCT). Study end-points were proven invasive fungal infection (IFI), survival, adverse reactions and graft-vs.-host disease (GVHD); 53 children and one young adult (median age 8.6 yr; range 0.4-18.3) transplanted between November 2001 and August 2004 were included in this study. Itraconazole was given intravenously from day +3 after HCT until oral medication became possible and continued until day +100 after HCT. Two proven new IFI in the itraconazole group (candidiasis, n = 1; aspergillosis, n = 1) were observed. After a median follow-up of 1.6 yr (0.3-6.1), six deaths (8%) were seen; 24 patients (45%) developed GVHD degree I-II, three children (6%) had GVHD degree III-IV. In 11 of 53 patients (21%), itraconazole prophylaxis was discontinued prematurely, mostly because of fever of unknown origin (n = 7). In total, 21 of 53 (40%) of the children had abnormal results of laboratory investigations during the prophylaxis. The results of this pilot study indicate that itraconazole prophylaxis during HCT in children is feasible and safe, despite abnormal laboratory results. The efficacy in terms of prevention of IFI, however, has to be addressed in a prospective large-scale study.

Expression of the chemokine receptor CXCR1 in human glomerular diseases

Leukocyte infiltration, a hallmark of renal diseases, is orchestrated in part by the actions of chemokines. The chemokine CXCL8/interleukin (IL)-8 is expressed during renal diseases and allograft rejection, whereas the corresponding receptor CXCR1 has not been described previously. Expression of CXCR1 was characterized in peripheral blood using multicolor fluorescence-activated cell sorter analysis (FACS). CXCR1 was localized in 81 formalin-fixed, paraffin-embedded renal specimens by immunohistochemistry using a monoclonal antibody against human CXCR1. Included were biopsies with crescentic glomerulonephritis (CGN, n = 22), immunoglobulin (Ig) A nephropathy (n = 15), membranoproliferative glomerulonephritis (MPGN, n = 17), lupus nephritis (n = 12), membranous nephropathy (n = 11), and non-involved parts of tumor nephrectomies (n = 4). Consecutive tissue sections of human tonsils, allograft explants, and renal biopsies were stained for CD15- and CD68-positive cells. Expression of CXCR1 and CXCL8/IL-8 mRNA was quantified by real-time reverse transcriptase-polymerse chain reaction of microdissected renal biopsies (n = 35) of the same disease entities. By FACS CXCR1 expression was found on polymorphonuclear CXCR1 expression by polymorphonuclear leukocytes (PMNs), natural killer cells, and a subpopulation of monocytes. By immunohistochemistry, CXCR1 expression was found on infiltrating inflammatory cells (predominantly PMNs), as well as on intrinsic renal cells (arterial smooth muscle cells, endothelial cells of peritubular capillaries). The distribution pattern of CXCR1 differed between disease entities. The highest numbers of glomerular CXCR1-positive cells were present in biopsies with MPGN, followed by lupus nephritis, and CGN. CXCR1 might be involved in the recruitment of PMNs to the glomerular tuft, which could be targeted by CXCR1-blocking agents.

A Computationally Efficient Optimization Kernel for Material Parameter Estimation Procedures

Estimating material parameters is an important part in the study of soft tissue mechanics. Computational time can easily run to days, especially when all available experimental data are taken into account. The material parameter estimation procedure is examplified on a set of homogeneous simple shear experiments to estimate the orthotropic constitutive parameters of myocardium. The modification consists of changing the traditional least-squares approach to a weighted least-squares. This objective function resembles a L2-norm type integral which is approximated using Gaussian quadrature. This reduces the computational time of the material parameter estimation by two orders of magnitude.

Single-dose actinomycin D: Efficacy in the prophylaxis of postmolar gestational trophoblastic neoplasia in adolescents with high-risk hydatidiform mole

OBJECTIVE

To evaluate the efficacy of a single prophylactic dose of actinomycin D (Act-D) in the reduction of postmolar gestational trophoblastic neoplasia (GTN) in adolescents with high-risk hydatidiform mole (Hr-HM).

METHODS

In a retrospective study, 60 adolescents with Hr-HM were selected from a cohort of patients with gestational trophoblastic disease (GTD) followed at Santa Casa, Porto Alegre, Brasil. Twenty-nine received a single dose of Act-D at the time of uterine evacuation as prophylactic chemotherapy (P-chem) (study group) and 31 patients with the same risk factors did not received P-chem (control group). Patient follow-up was the same in both groups. Each group was analyzed for number of adolescents with postmolar GTN, morbidity associated with postmolar GTN, and reproductive outcomes.

RESULTS

Postmolar GTN was diagnosed in two (6.9%) adolescents (95% CI, 0.0-16.1) in the study group and in 9 (29.0%) patients (95% CI, 13-45) in the control group. The reduction of postmolar GTN with a single dose of Act-D used as P-chem was 76% (relative risk = 0.24; 95% CI, 0.06-0.99). Adverse effects of P-chem were minor. In the follow-up, when postmolar GTN were diagnosed, severity of disease was not increased, compliance with follow-up was not reduced, and reproductive outcomes after discharge were similar.

CONCLUSIONS

P-chem with a single dose of Act-D reduced postmolar GTN in 76% during follow-up of adolescents with Hr-HM. Since this regimen may reduce treatment costs, without affecting compliance with follow-up, it can be adopted by any Trophoblastic Disease Center.

Outbreak of human listeriosis associated with tomme cheese in northwest Switzerland, 2005

During an eight week period in spring 2005, 10 cases of listeriosis were reported in a small area of northwest Switzerland (150 000 inhabitants). Eight cases were in older immunocompromised patients who became ill with bacteraemia (three deaths), and two cases were in pregnant women who had septic abortion.

HIV-Associated Renal Diseases and Highly Active Antiretroviral Therapy--Induced Nephropathy

Renal disease is becoming an increasingly prevalent entity in human immunodeficiency virus (HIV)-infected patients; it occurs in a variety of clinical settings and is associated with histopathological changes. HIV-related renal impairment can present as acute or chronic kidney disease; it can be caused directly or indirectly by HIV and/or by drug-related effects that are directly nephrotoxic or lead to changes in renal function by inducing metabolic vaculopathy and renal damage. Acute renal failure is frequently caused by the toxic effects of antiretroviral therapy or nephrotoxic antimicrobial substances used in the treatment of opportunistic infections. Chronic renal disease can be caused by multiple pathophysiological mechanisms, leading to HIV-associated nephropathy, a form of collapsing focal glomerulosclerosis, thrombotic microangiopathy, and various forms of immune complex glomerulonephritis. The increase in life expectancy and alteration of lipid metabolism due to receipt of highly active antiretroviral therapy are expected to result in an increased prevalence of diabetes and hypertension and, thus, to secondary diabetic and hypertensive renal damage. Antiretroviral agents, such as indinavir and tenofovir, have been associated with nephrotoxic drug effects that have been shown to be reversible in most cases. In this article, we review the current knowledge about acute and chronic HIV-associated renal disease, metabolic alterations and related nephropathies, and toxic drug effects of combination antiretroviral pharmacotherapy.

Myocardial Material Parameter Estimation—A Comparative Study for Simple Shear

The study of ventricular mechanics—analyzing the distribution of strain and stress in myocardium throughout the cardiac cycle—is crucially dependent on the accuracy of the constitutive law chosen to represent the highly nonlinear and anisotropic properties of passive cardiac muscle. A number of such laws have been proposed and fitted to experimental measurements of stress-strain behavior. Here we examine five of these laws and compare them on the basis of (i) “goodness of fit:” How well they fit a set of six shear deformation tests, (ii) “determinability:” How well determined the objective function is at the optimal parameter fit, and (iii) “variability:” How well determined the material parameters are over the range of experiments. These criteria are utilized to discuss the advantages and disadvantages of the constitutive laws.