Sjögren's syndrome X-chromosome dose effect: An epigenetic perspective.

Sjögren's syndrome (SS) is a chronic autoimmune disease affecting exocrine glands leading to mouth and eyes dryness. The extent to which epigenetic DNA methylation changes are responsible for an X-chromosome dose effect has yet to be determined. Our objectives were to (i) describe how epigenetic DNA methylation changes could explain an X-chromosome dose effect in SS for women with normal 46,XX genotype and (ii) determine the relevant relationships to this dose effect, between X-linked genes, genes controlling X-chromosome inactivation (XCI) and genes encoding associated transcription factors, all of which are differentially expressed and/or differentially methylated in the salivary glands of patients with SS. We identified 58 upregulated X-chromosome genes, including 22 genes previously shown to escape XCI, based on the analysis of SS patient salivary gland GEO2R gene expression datasets. Moreover, we found XIST and its cis regulators RLIM, FTX, and CHIC1, and polycomb repressor genes of the PRC1/2 complexes to be upregulated. Many of the X-chromosome genes implicated in SS pathogenesis can be regulated by transcription factors which we found to be overexpressed and/or differentially methylated in patients with SS. Determination of the mechanisms underlying methylation-dependent gene expression and impaired XCI is needed to further elucidate the etiopathogenesis of SS.

Unfolding of the [Cu2(1,3-bis(9-methyl-1,10-phenanthrolin-2-yl)propane)2]2+ helicate. Coupling of the chlorocarbon dehalogenation to the unfolding process.

A new helical dimeric copper(I) complex [Cu(2)(mphenpr)(2)](ClO(4))(2) where mphenpr is 1,3-bis(9-methyl-1,10-phenanthrolin-2-yl)propane has been prepared and characterized by X-ray crystallography and NMR. In the solid state, the metal centers are 6.42 A apart, and the electronic structure has been investigated with use of density functional theory (DFT) calculations. In solution the dimer equilibrates with a monomeric form [Cu(mphenpr)](ClO(4)), and the mechanism of unfolding of the dimer into monomer has been studied. In the presence of CCl(4), formation of the monomer is coupled to the reductive dehalogenation of the halocarbon. The mechanism of this process has been probed by the study of short-lived potential reaction intermediates using fast kinetic pulse radiolysis techniques and comparisons with DFT calculations. The copper(II) product [Cu(mphenpr)Cl](ClO(4)) and an analogue [Cu(mphenpr)](ClO(4))(2) have been isolated and characterized by X-ray crystallography.

Effect of dust exposure and nitrogen oxides on lung function parameters of German coalminers: a longitudinal study applying GEE regression 1974-1998.

PURPOSE: Workplace limits for dust and nitrogen oxides are under review in Germany and the EU. We conducted a study on German coal miners to determine the effects of exposure on lung function. METHODS: Longitudinal inception cohort study (1974-1998) on miners who began working underground at two coal mines between 1974 and 1979. We determined the number of shifts worked underground, the exposure to coal mine dust, quartz dust, nitrogen oxides (NO, NO(2)), smoking behavior, and three lung function parameters (FVC, FEV(1), FEV(1)/FVC). General estimation equation (GEE) models were fitted. RESULTS: 1,369 miners worked an average 3,017 shifts (S) underground. The mean respirable coal mine dust concentration was 1.89 mg/m(3) (quartz: 0.067 mg/m(3)), and the nitrogen oxide concentrations were 0.58 ppm (NO) and 0.007 ppm (NO(2)). On average, 9 measurements of lung function were available per miner. Compared to reference values, the findings were unexceptionable (103, 101, and 99%) on average. GEE-regression models did not reveal detrimental dust exposure effects. Nitrogen oxides (NO (x) = NO + NO(2)) showed small but clearly insignificant effects on lung function: delta FVC = -0.0008 ml/(220 ppmS), P = 0.86, delta FEV(1) = -0.003 ml/(220 ppmS), P = 0.50 and delta FEV(1)%FVC = -0.07%/(220 ppmS), P = 0.22. CONCLUSIONS: The effect of dust exposure on lung function described in older British and American coal miner studies was not confirmed. This can be explained partly by differences in methods (here: longitudinal studies, no prior exposure), but also by lower dust levels. NO (x) exposures showed no relevant influence on lung function-a result confirming findings from British coal mining.

Exploring the feasibility of email-mediated interaction in survivors of abuse.

There is a growing use of email-based provision of information, development of health-related skills and interventions; however, use of email to assist women and children experiencing abuse after receiving Protection from Abuse (PFA) court order has not been explored. The specific aim of this research was to test the feasibility of an email device called MIVO for use in interacting with women and children after receiving PFA. This qualitative design used a three-step recruitment, screening and email interaction with mothers and their adolescent child after obtaining informed consent and training in the use of an email device. Sample included six pairs of mother and child (n = 12) who have received a PFA within the past 6 months. Demographic data were gathered using the sociodemographic questionnaire. Qualitative data were gathered using email messages from mother and child pairs. Results showed that email interaction is a feasible and acceptable way of providing support and information to survivors of abuse after their PFA. The following themes in their order and rank of appearance were found in the email interaction between the nurse and survivors: (1) safety issues; (2) job-related issues; (3) school-related issues; (4) parenting-related issues; and (5) health-related issues. Themes identified for the children were school work and friends. Privacy, confidentiality and respect for individual rights are paramount in email interactions. Email interaction is useful in education, screening, safety instructions and follow-up care. Technological devices such as MIVO may have usefulness as an email interaction device among women, their child and a nurse to reduce their risk for further interpersonal violence/abuse and to increase disclosure of abuse. Healthcare providers need to identify technological developments, and through evidence-based research examine their feasibility and adaptability for translation into practice specifically, in caring for survivors of abuse.

Quantification of oligodeoxynucleotides in human plasma with a novel hybridization assay offers greatly enhanced sensitivity over capillary gel electrophoresis.

Capillary gel electrophoresis using UV detection (CGE-UV) has been used to quantify oligodeoxynucleotides (ODN) in human plasma. Although the sensitivity of this method is adequate to detect antisense ODN, which are administered in daily doses up to 10 mg/kg, CGE-UV is not sensitive enough to detect the much lower quantities of ODN administered for other purposes, such as immune stimulation by CpG ODN. We have developed a very sensitive colorimetric hybridization assay that increases the sensitivity of detection by more than four logs compared with CGE-UV. The hybridization assay uses sequence-specific capture and detection ODN probes complementary to portions of the ODN sequence. Herein we provide a prototype for assay development and validation using a 24- mer immunostimulatory phosphorothioate ODN. Probes were locked nucleic acids (LNA), resulting in increased sensitivity and specificity. The linear range of the assay is 7.8-1000 pg/ml, with a 7.8 pg/ml lower limit of quantification (LLOQ) and a detection limit of 2.8 pg/ml. This translates to detection of 40 attamoles. Intraassay and interassay precision were < or =5.0% CV and < or =12.9% CV, respectively, for quality control samples. The assay is suitable for a variety of matrices, including monkey and rat plasma, allowing application to toxicokinetic samples. The methodology is highly specific, with the ability to distinguish almost all single-base mismatched ODN. The assay detects 100% of the parent as well as some metabolites up to N-4, which are known to be the primary metabolites forming in the first hours after in vivo administration and are physiologically active with in vitro assays.

Syntheses of a Cp'Re=S derivative and more complex products.

The reaction of Cp'ReCl(2)S(3) (Cp' = Me(4)EtC(5)) with slightly less than 2 equiv of a phosphine reagent results in the formation of [Cp'Re(Cl)(2)(mu-S)](2), 2, which has been characterized by an X-ray diffraction study. Reactions of 2 with nucleophiles did not lead to monomeric derivatives of the type Cp'ReS(Cl)(2)(Nuc). The reaction of Cp'ReCl(2)(SC(2)H(4)S) with (Me(3)Si)(2)S resulted in the formation of three new products: Cp'ReS(SC(2)H(4)S), 4; Cp'Re(S(3))(SC(2)H(4)S), 5; and a tetranuclear derivative, [(Cp'Re)(2)(mu-S)(mu,eta(2)-SC(2)H(4)S)(mu,eta(1)-SC(2)H(4)S](2)Cl(2), 6. Complexes 4 and 6 have been characterized by X-ray diffraction studies. The electrochemical properties of the mononuclear Re=S derivative, 4, are compared with those of Re=O and Re=NR analogues.

Salmonella isolated from animals and feed production in Sweden between 1993 and 1997.

This paper presents Salmonella data from animals, feedstuffs and feed mills in Sweden between 1993 and 1997. During that period, 555 isolates were recorded from animals, representing 87 serotypes. Ofthose, 30 serotypes were found in animals in Sweden for the first time. The majority of all isolates from animals were S. Typhimurium (n = 91), followed by S. Dublin (n = 82). There were 115 isolates from cattle, 21 from broilers, 56 from layers and 18 from swine. The majority of these isolates were from outbreaks, although some were isolated at the surveillance at slaughterhouses. The number of isolates from the feed industry was similar to that of the previous 5-year period. Most of those findings were from dust and scrapings from feed mills, in accordance with the HACCP programme in the feed control programme. It can be concluded that the occurrence of Salmonella in animals and in the feed production in Sweden remained favourable during 1993-97.

Tc and Re chelates of 8alpha-amino-6-methyl-ergoline: synthesis and affinity to the dopamine D2 receptor.

The influence of structural changes at the 8alpha-amino position of 8alpha-amino-6-methyl-ergoline on the lipophilicity and affinity to the D2 receptor was studied. 8alpha-amino-6-methyl-ergoline (1) was converted into the derivatives (2a-f) by mercaptoacetylation of the amino group to make it possible to prepare the rhenium and technetium complexes (3, 4a,b). Binding tests on cloned human dopamine D2 receptors show that the affinities of the coordination compounds (IC50 values between 50 and 240 nM) are less than those of the derivatives 2a-f (IC50=3-50 nM) but more than those of the parent compound 1. Biodistribution studies of the Tc complexes 4a,b performed on Wistar rats show a slow blood clearance with substantial accumulation and retention in the liver and kidneys and low brain uptake.

Reactions of dithiolate ligands in mononuclear complexes of rhenium(V).

The thermal reactions of the Re(V) dithiolate complex Cp'ReCl2(SCH2CH2S), 1 (where Cp' = EtMe4C5), and related derivatives have been studied. When 1 is heated in toluene in a sealed evacuated tube at 100 degrees C, a dehydrogenation reaction occurs to form a new rhenium complex with a dithiolene ligand, Cp'ReCl2(SCHCHS), 6, in ca. 40% yield. The structure of 6 has been confirmed by an X-ray diffraction study. Under the thermal conditions studied, 1 also undergoes an olefin extrusion reaction. Free ethene is detected in the NMR spectrum of the products, and insoluble rhenium products are also formed. When 1 is reacted with excess ethene under mild conditions, a new organic product, 1,4-dithiane, is formed. Complex 1 is also found to react with oxidants, such as O2 and S8, under mild conditions to form the dehydrogenation product 6. Kinetic studies of the thermal reaction of 1 and related derivatives have been completed, and possible mechanisms for the thermally induced dehydrogenation reaction are discussed.

A remarkable skeletal rearrangement of a coordinated tetrapyrrole: chemical consequences of palladium pi-coordination to a bilindione.

Pd4(OEB)2, in which a [Pd2]2+ unit is bound in pi-fashion to olefinic sites that are exocyclic to pyrrole rings of the octaethylbilindione ligand, undergoes an unprecedented sequence of reactions that results in the rearrangement of the framework of the bilindione ligand and the formation of trans-Pd(py)2I2. This process of bilindione rearrangement and oxidation occurs as a direct consequence of the pi-coordination of the palladium. The reaction results in the migration of a nitrogen atom from a pyrrole carbon atom to what was formerly a meso carbon atom to transform a former pyrrole ring into a six-membered ring. This process also involves cleavage of the Pd-Pd and Pd-C bonds, oxidation of palladium, and introduction of an oxygen atom (from water) not necessarily in this particular sequence.

Comparison of [18F]FHPG and [124/125I]FIAU for imaging herpes simplex virus type 1 thymidine kinase gene expression.

Various radiotracers based on uracil nucleosides (e.g. [124I]2'-fluoro-2'-deoxy-5-iodo-1-beta-D-arabinofuranosyluracil, [124I]FIAU) and acycloguanosine derivatives (e.g. [18F]9-[(3-fluoro-1-hydroxy-2-propoxy) methyl] guanine, [18F]FHPG) have been proposed for the non-invasive imaging of herpes simplex virus type 1 thymidine kinase (HSV1-tk) reporter gene expression. However, these radiotracers have been evaluated in different in vitro and in vivo models, precluding a direct comparison. Therefore, we directly compared [18F]FHPG and radioiodinated FIAU to assess their potential for PET imaging of transgene expression. The uptake of [125I]FIAU, [18F]FHPG and [3H]acyclovir was determined in vitro using four different HSV1-tk expressing cell lines and their respective negative controls. The in vitro tracer uptake was generally low in non-transduced parental cell lines. In HSV1-tk expressing cells, [3H]acyclovir showed approximately a twofold higher tracer accumulation, the [18F]FHPG uptake increased by about sixfold and the [125I]FIAU accumulation increased by about 28-fold after 120-min incubation of T1115 human glioblastoma cells. Similar results were found in the other cell lines. In addition, biodistribution and positron emission tomography (PET) studies with [18F]FHPG and [124/125I]FIAU were carried out in tumour-bearing BALB/c mice. Significantly higher specific accumulation of radioactivity was found for [125I]FIAU compared with [18F]FHPG. The ratio of specific tracer accumulation between [125I]FIAU and [18F]FHPG increased from 21 (30 min p.i.) to 119 (4 h p.i.). PET imaging, using [124I]FIAU, clearly visualised and delineated HSV1-tk expressing tumours, whereas only a negligible uptake of [18F]FHPG was observed. This study demonstrated that in vitro and in vivo, the radioiodinated uracil nucleoside FIAU has a significantly higher specific accumulation than the acycloguanosine derivative [18F]FHPG. This suggests that [124I]FIAU should be the preferred reporter probe for PET imaging of HSV1-tk gene expression. Thus, further attempts to develop suitable PET tracers for the assessment of HSV1-tk gene expression should also focus on 18F-labelled uracil derivatives.

Prophylaxis of restenosis with (186)re-labeled stents in a rabbit model.

BACKGROUND: Intraluminal beta-irradiation has been shown to decrease neointimal proliferation after angioplasty in experimental models. The purpose of this study was to test the technical feasibility and biological effects of (186)Re-labeled stents. METHODS AND RESULTS: Thirty-four New Zealand White rabbits were fed a 0.5% cholesterol diet before balloon angioplasty and insertion of Palmaz stents in the infrarenal aorta. The animals were killed 7 weeks after stent implantation. Two of 34 animals died prematurely (aortic leak, pneumonia). Control stents (n=7) were compared with (186)Re stents (2.6 MBq [n=6], 8.1 MBq [n=5], 16.0 MBq [n=6], and 25.3 MBq [n=8]). Stent application was successful in all cases. No thrombus occlusion was observed. After 7 weeks, neointima formation was 2.2+/-0.2 mm(2) in the control group. In the treatment groups, a dose-dependent neointima reduction was detectable (0.5+/-0.5 mm(2) [2.6 MBq], 0.4+/-0.4 mm(2) [8.1 MBq], and 0 mm(2) [16.0 MBq, 25.3 MBq]). No induction of neointimal formation was observed at the edges of the stents. Radiation resulted in delayed reendothelialization. CONCLUSIONS: (186)Re stents were capable of reducing neointima formation in a dose-dependent fashion. (186)Re stents did not cause late thrombosis or neointimal induction at the stent margins in the observation period of 7 weeks.

Hyperinsulinemia, lipoprotein (a), and Chlamydia pneumoniae antibodies--are they risk factors or serologic predictors for progression of coronary artery disease?

The authors studied 134 patients with unstable angina pectoris symptoms and 32 subjects without coronary artery disease (CAD) for the presence of classical risk factors such as hypercholesterolemia, smoking, and family history of CAD. In addition they analyzed plasma insulin levels, lipoprotein (a) (Lp [a]) levels, and antibody titers against Chlamydia pneumoniae. All patients had a heart catheterization. Patients with diabetes mellitus were excluded from the study. Fasting insulin, low-density lipoprotein (LDL) cholesterol and Chlamydia pneumoniae immunoglobulin G (IgG) and IgA antibody titers did not show any difference in CAD from healthy control subjects, whereas Lp(a) was increased and high-density lipoprotein (HDL) decreased in CAD patients. These data indicate that lipoprotein (a), low HDL cholesterol, and smoking, but neither hyperinsulinemia nor elevated Chlamydia pneumoniae titers, are risk factors or predictors for CAD.

[Recurrent ventricular fibrillation after defibrillation in a patient with pacemaker]. / Rezidivierendes Kammerflimmern nach Defibrillation bei einem Schrittmacherpatienten.

HISTORY: A 62-year-old patient was admitted for an operation of a hernia of the right groin in the surgical department. He had a dual chamber pacemaker because of a binodal disease. Pre-operatively the patient was reanimated because of ventricular fibrillation in dilated cardiomyopathy and was defibrillated 12 times, unexpectedly often. DIAGNOSIS: The reason of the repeated ventricular fibrillation was a spike-on-T-phenomenon due to loss of the sensing function of the pacemaker (entrance bloc). TREATMENT: Therefore, the pacemaker was explanted, and the ventricular fibrillation came to an end. The patient recovered. CONCLUSIONS: The repeated defibrillations with the electrodes over the basis and the apex of the heart damaged the pacemaker. The following fibrillation episodes were founded on a spike-on-T-phenomenon. In order to prevent such damage of pacemakers, pacemaker patients should be defibrillated and cardioverted in anterior-posterior position of the electrodes.

Restenosis after percutaneous coronary interventions and infection.

Infectious agents may directly or indirectly (through the response of the host's immune system) modulate the growth of vascular cells. Local and/or systemic increase of cytokines could influence the extent of (re-)stenosis in the vascular tree. Further studies in this field may identify patients at a high risk for atherogenesis and restenosis. Their results should be helpful in treating restenosis after percutaneous coronary interventions.

Strategies to optimize CAD prevention in modern cardiology. The "Marburg CAD Prevention Project".

In recent years we identified numerous cardiovascular risk factors and had been able to reduce cardiovascular events by a variety of different interventions. There is no question that we can improve the course of coronary artery disease (CAD) in patients with a high-risk profile by modifying these factors. Despite this knowledge, many patients with known CAD or myocardial infarction are not treated for secondary prevention as recommended by well established guidelines (http:¿www.chd-taskforce.com). In order to improve secondary prevention in our patients we started a project, the so called "Marburg CAD Prevention Project". By this we combine our computer data base of the CAD preventional routine laboratory with the computer program CARDDAS. Individual risk factors and the angiographic findings were analyzed. Patients as well as local physicians were informed on the need to treat the important risk factors. This approach ensures that at least all of our patients with documented CAD receive the appropriate preventional recommendations and treatment.