Sorption competition and kinetics of trivalent cations (Eu, Y and Cm) on corundum (alpha-Al2O3 ) : A batch sorption and TRLFS study

Abstract In this study we have combined batch sorption and laser spectroscopic investigations to study the sorption of Eu(III) and Cm(III), on the aluminum oxide corundum in single- and multi-metal systems. Experiments were performed using a constant equilibrium time as a function of pH (pH-edges) or at constant pH as a function of equilibrium time (kinetic experiments) in 0.01 M NaClO4 and carbonate free conditions. The objective was to investigate how the sorption behavior of trivalent actinides and lanthanides is affected by the presence of another trivalent metal, Y(III). Our hypothesis was that the addition of higher concentrations of trivalent Y(III) together with a chemically similar trivalent metal, Eu(III) or Cm(III), would affect the sorption behavior of that metal. Batch experiments show that when the concentration of competing Y(III) is high enough (1 × 10−4 M) to occupy most of the surface sites, there is a clear shift in the position of the Eu(III) pH-edge to higher pH. Spectroscopic studies using time-resolved laser fluorescence spectroscopy (TRLFS) clearly confirm sorption competition between the trivalent metals Cm(III) and Y(III), but they also indicate a change in the surface speciation of the trivalent actinide in the presence of the competing metal if the concentration of that competing metal is high enough.Peer reviewe

Understanding the local structure of Eu3+- and Y3+-stabilized zirconia: insights from luminescence and X-ray absorption spectroscopic investigations

This study combines bulk structural and spectroscopic investigations of Eu$^{3+}$- or Y$^{3+}$/Eu$^{3+}$ co-doped tetragonal and cubic zirconia polymorphs to gain an indepth understanding of the solid solution formation process. Our bulk structural characterizations show that the dopant is homogenously distributed in the ZrO$_{2}$ host structure resulting in an increase of the bulk symmetry with increasing dopant substitution (from 8 to 26 mol%). The local site symmetry around the Eu$^{3+}$ dopant, however, determined with luminescence spectroscopy (TRLFS), remains low in all samples. Results obtained with X-ray pair distribution function and X-ray absorption spectroscopy show that the average coordination environment in the stabilized zirconia structures remains practically unchanged. Despite this very constant average dopant environment, siteselective TRLFS data show the presence of three nonequivalent Eu$^{3+}$ environments in the ZrO$_{2}$ solid structures. These Eu$^{3+}$ environments are assumed to arise from Eu$^{3+}$ incorporation at superficial sites, which increase in abundance as the size of the crystallites decrease, and incorporation on two bulk sites differing in the location of the oxygen vacancies with respect to the dopant cation

Chlamydia pneumoniae, heat shock proteins 60 and risk of secondary cardiovascular events in patients with coronary heart disease under special consideration of diabetes: a prospective study

BACKGROUND: There have been suggestions of an association between Chlamydia pneumoniae, chlamydial heat shock protein (Ch-hsp) 60 and human heat shock protein (h-hsp) 60 infection sero-status and development of secondary cardiovascular events. Patients with diabetes might be at higher risk since they are prone to infections. The objective of this study was to investigate prospectively the role of Chlamydia pneumoniae (CP), chlamydial heat shock protein (Ch-hsp) 60 and a possible intermediate role of human heat shock protein (h-hsp) 60 sero-status in the development of secondary cardiovascular disease (CVD) events in patients with coronary heart disease (CHD) under special consideration of diabetes mellitus. METHODS: Patients aged 30–70 undergoing an in-patient rehabilitation program after acute manifestation of coronary heart disease (International Classification of Disease, 9(th )Rev. pos. 410–414) between January 1999 and May 2000 in one of two participating rehabilitation clinics in Germany were included in this analysis. Chlamydia pneumoniae (CP), chlamydial heat shock protein (Ch-hsp) 60 and human heat shock protein (h-hsp) 60 status at baseline were measured by serum immunoglobulin G and A antibodies. Secondary CVD events (myocardial infarction, stroke, and cardiovascular death) were recorded during a mean follow-up period of 33.5 months (response = 87%). RESULTS: Among the 1052 subjects 37.4% and 39.3% were sero-positive to CP IgA and IgG respectively, 22.2% were sero-positive to Ch-hsp 60 IgG and 8.4% were positive to h-hsp 60 IgG at baseline. During follow-up, secondary CVD events occurred among 71 (6.8%) participants. Occurrence of a secondary CVD event was more common among CP (IgA) and CP (IgG) sero-positive than among sero-negative patients (p-values 0.04 and 0.1, respectively). The risk of secondary CVD events was increased among patients with both a positive CP sero-status and diabetes compared to infection negative, non-diabetic patients and in general, sero-positivity added a hazard to diabetes. The interaction term between infection sero-status and diabetes was not statistically significant. We were not able to show an intermediate role of human heat shock protein (h-hsp) 60 sero-status in the development of secondary CVD events in patients with CHD. CONCLUSION: Results from this cohort of 1052 patients with pre-existing CHD cannot exclude a possible moderate increase in risk of secondary CVD events among patients with a positive infection sero-status. However, our study showed no intermediate role of human heat shock protein (h-hsp) 60 sero-status in the development of secondary CVD events in patients with CHD. Larger studies or meta-analysis of multiple studies are needed to address the interaction between infection sero-status and diabetes with adequate power

Pelvic trauma : WSES classification and guidelines

Complex pelvic injuries are among the most dangerous and deadly trauma related lesions. Different classification systems exist, some are based on the mechanism of injury, some on anatomic patterns and some are focusing on the resulting instability requiring operative fixation. The optimal treatment strategy, however, should keep into consideration the hemodynamic status, the anatomic impairment of pelvic ring function and the associated injuries. The management of pelvic trauma patients aims definitively to restore the homeostasis and the normal physiopathology associated to the mechanical stability of the pelvic ring. Thus the management of pelvic trauma must be multidisciplinary and should be ultimately based on the physiology of the patient and the anatomy of the injury. This paper presents the World Society of Emergency Surgery (WSES) classification of pelvic trauma and the management Guidelines.Peer reviewe

Seroprevalence of 13 common pathogens in a rapidly growing U.S. minority population: Mexican Americans from San Antonio, TX

<p>Abstract</p> <p>Background</p> <p>Infection risks vary among individuals and between populations. Here we present information on the seroprevalence of 13 common infectious agents in a San Antonio-based sample of Mexican Americans. Mexican Americans represent the largest and most rapidly growing minority population in the U.S., and they are also considered a health disparities population.</p> <p>Methods</p> <p>We analyzed 1227 individuals for antibody titer to <it>Chlamydophila pneumoniae, Helicobacter pylori, Toxoplasma gondii</it>, cytomegalovirus, Epstein-Barr virus, herpes simplex virus-1, herpes simplex virus-2 (HSV-2), human herpesvirus-6 (HHV-6), varicella zoster virus (VZV), adenovirus-36, hepatitis A virus, and influenza A and B. Seroprevalence was examined as a function of sex, age, household income, and education.</p> <p>Results</p> <p>Seroprevalence estimates ranged from 9% for <it>T. gondii</it> to 92% for VZV, and were similar in both sexes except for HSV-2, which was more prevalent in women. Many pathogens exhibited a significant seroprevalence change over the examined age range (15-94 years), with 7 pathogens increasing and HHV-6 decreasing with age. Socioeconomic status significantly correlated with serostatus for some pathogens.</p> <p>Conclusions</p> <p>Our findings demonstrate substantial seroprevalence rates of these common infections in this sample of Mexican Americans from San Antonio, Texas that suffers from high rates of chronic diseases including obesity and type-2 diabetes.</p

Human anti-60 kD heat shock protein autoantibodies are characterized by basic features of natural autoantibodies

Anti-human Hsp60 autoantibodies--known risk factor of atherosclerosis--were investigated in a mouse model and in samples of healthy subjects: polyreactivity, presence in cord blood samples of healthy newborns and life-long stability were tested. In IgM hybridoma panel from mouse spleens, polyreactivity of anti-Hsp60 autoantibodies was studied. In healthy pregnant women, umbilical vein and maternal blood samples were collected after childbirth, anti-Hsp-60 and -65 IgM and IgG levels were measured. Life-long stability of anti-Hsp-60 levels was studied on healthy patients during 5 years. ELISA was used in all studies. Polyreactivity of IgM clones of newborn mice and lifelong stability of these autoantibodies in healthy adults were established. IgM anti-Hsp60 autoantibodies in cord blood of healthy human infants were present, however, there was no correlation between maternal and cord blood IgM anti-Hsp60 concentrations. It is proposed that presence of anti-Hsp60 autoantibodies--as part of the natural autoantibody repertoire--may be an inherited trait. Level of anti-Hsp60 autoantibodies may be an independent, innate risk factor of atherosclerosis for the adulthood

Imaging and Endovascular Treatment of Bleeding Pelvic Fractures: Review Article

Pelvic fractures are potentially life-threatening injuries with high mortality rates, mainly due to intractable pelvic arterial bleeding. However, concomitant injuries are frequent and may also be the cause of significant blood loss. As treatment varies depending on location and type of hemorrhage, timely imaging is of critical importance. Contrast-enhanced CT offers fast and detailed information on location and type of bleeding. Angiography with embolization for pelvic fracture hemorrhage, particularly when performed early, has shown high success rates as well as low complication rates and is currently accepted as the first method of bleeding control in pelvic fracture-related arterial hemorrhage. In the current review imaging workup, patient selection, technique, results and complications of pelvic embolization are described

<em>Chlamydia pneumoniae</em> infection, inflammation and heat shock protein 60 immunity in asthma and coronary heart disease

Abstract Chlamydia pneumoniae is a common respiratory pathogen worldwide. It does not only cause acute respiratory infections, but is also associated with chronic inflammatory diseases, such as asthma and coronary heart disease (CHD). Chlamydial heat shock protein 60 (Hsp60) is associated with the development of immunopathological damage following C. trachomatis infections, but the role of Hsp60 in C. pneumoniae infections is unclear. A slightly elevated level of C-reactive protein (CRP), as a marker of systemic inflammation, predicts cardiovascular events, but its role in asthma has not been studied. The aim of this study was to develop an EIA method for the measurement of Hsp60 antibodies and for studying the host immune responses to C. pneumoniae and chlamydial and human Hsp60 proteins, CRP levels and their interactions in asthma and CHD. Elevated levels of serum IgA antibodies to the Hsp60 protein of C. pneumoniae were associated with asthma and decreased pulmonary function. CRP levels were also higher in the asthma patients than in the controls. The patients with moderate asthma had higher CRP levels than those with mild asthma. The patients with a CRP level over 2 mg/l had higher levels of serum IgA antibodies to C. pneumoniae and chlamydial Hsp60 than the patients with lower CRP levels. A prospective nested case-control study was carried out, to study the role of Hsp60 antibodies as coronary risk predictors, and their association with C. pneumoniae infection and inflammation. The participants were obtained from the Helsinki Heart Study: 241 myocardial infarctions or coronary deaths occurred during the 8.5-year period among dyslipidemic middle-aged men. An elevated level of human Hsp60 IgA antibodies in baseline serum predicted the occurrence of a coronary event several years later, especially when present simultaneously with a high C. pneumoniae IgA antibody level and an elevated CRP level. Further studies showed that only persistently, not transiently, elevated levels predicted coronary events. The risk associated with elevated antibody levels increased markedly in the presence of an elevated CRP level, and vice versa. In conclusion, these results suggest that chlamydial Hsp60 is involved in the association between C. pneumoniae infection and asthma, while autoimmunity to human Hsp60 is implicated in the association between C. pneumoniae infection and CHD. Inflammation evidently plays an important role in these associations. It can also be concluded that IgA antibodies, compared to IgG antibodies, against C. pneumoniae and Hsp60 are better markers of chronicity, especially when they are persistently elevated