Clinical safety and efficacy of a single-dose gentamicin, posaconazole and mometasone furoate otic suspension for treatment of canine otitis externa

BACKGROUND

A single-dose, in-clinic, veterinary professional-administered treatment for canine otitis externa was developed to improve compliance and canine welfare.

METHODS

This multicentre, controlled, examiner-masked, randomised field trial was conducted in 316 dogs over 42 days. Dogs were treated once, on day 0, with the investigational product containing gentamicin, posaconazole and mometasone furoate (Mometamax Ultra [MU]) or twice (days 0 and 7) with a control product containing florfenicol, terbinafine and betamethasone acetate (CP). The primary endpoint was a composite otitis index score of 4 or less (of 12) on day 14 and 3 or less (of 12) on day 28.

RESULTS

On day 28, treatment success was recorded in 128 of 143 MU-treated dogs (89.5%), significantly non-inferior to 116 of 133 (87.2%) CP-treated dogs (Farrington-Manning test, Z = 4.1351, p < 0.0001). For mixed cultures of Staphylococcus pseudintermedius and Malassezia pachydermatis, there was 100% treatment success in MU-treated dogs (n = 33), significantly non-inferior to 90.2% (37 of 41) in CP-treated dogs (Farrington-Manning test, Z = 3.1954, p = 0.0007).

LIMITATIONS

Efficacy in chronic otitis externa cases was not investigated. Cytology was not used to aid in diagnosis or for identification of secondary pathogens.

CONCLUSION

This unique combination, single-dose product is safe and effective in dogs with otitis externa. It offers enhanced compliance, canine welfare and quality of life by eliminating the owner burden of treating this painful condition.

Detection and differentiation of active and inactive isoforms of coagulation factors II, VII, IX, and X in prothrombin complex concentrate by mass spectrometry

PURPOSE

Prothrombin complex concentrates (PCCs) are plasma products containing a mixture of four inactive/proactive coagulation factors. The activated forms of human coagulation factors, like Thrombin (FIIa), Convertin (FVIIa), activated Christmas factor (FIXa) and the activated Stuart-Prower factor (FXa), are impurities in PCCs. Until now no valid assay exists to differentiate the non activated proform (inactive) from active coagulation factor isoforms in PCCs in one measurement. Therefore, the aim of this study was to establish a mass spectrometry (LC-MS/MS)-based assay to address this issue in the ready to use medicinal product.

METHODS

Bottom-up proteomics combining double digestion (Glu-C & Lys-C) and LC-MS/MS, was used to differentiate the inactive and active forms of the coagulation factors Prothrombin (FII), Proconvertin (FVII), Christmas factor (FIX) and the Stuart-Prower-factor (FX) in PCCs.

RESULTS AND CONCLUSIONS

A targeted pseudo-multiple reaction monitoring (pMRM-LC-MS/MS)-assay was developed for the specific detection of four different coagulation factors in PCCs. Proteotypic peptides for the inactive/active isoforms (zymogen) of the four coagulation factors were identified and validated by the investigation of six investigational and one commercially available PCCs. In conclusion, the semi-quantitative determination and the distinction between the active and the inactive isoform of the respective coagulation factors were possible in one liquid chromatography tandem mass spectrometry (LC-MS/MS) run.

Carbon dots, a powerful non-toxic support for bioimaging by fluorescence nanoscopy and eradication of bacteria by photothermia

Carbon Dots (CDs) are innovative materials which have potential applications in many fields, including nanomedicine, energy and catalysis. Here CDs were produced by the alkali-assisted ultrasonic route and characterized by several techniques to determine their composition and properties. Fluorescence nanoscopy using single-molecule localization microscopy shows that they have very good photophysical properties and a remarkable blinking behaviour at 405 nm. Moreover, these CDs are a safe material, non-toxic towards different cell lines (cancer and non-cancer cells) even at very high concentration, reflecting an excellent biocompatibility. Photothermia, i.e. their heating capacity under laser irradiation, was evaluated at two wavelengths and at several power densities. The resulting temperature increment was high (5 < ΔT < 45 °C) and appropriate for biomedical applications. Bioimaging and photothermia were then performed on E. coli, a Gram(-) bacterium, incubated with CDs. Remarkably, by photothermia at 680 nm (0.3, 1 and 1.9 W cm^-2) or 808 nm (1.9 W cm^-2), CDs are able to eradicate bacteria in their exponential and stationary phases. Images obtained by 3D super-resolution microscopy clearly show the different CD distributions in surviving bacteria after mild photothermal treatment. These results confirm that CDs are multifunctional materials with a wide range of biomedical applications.

Maghemite nanoparticles coated with human serum albumin: combining targeting by the iron-acquisition pathway and potential in photothermal therapies

Human serum albumin (HSA), the most abundant plasma protein in human blood, is a natural transport vehicle with multiple ligand binding sites. It, therefore, constitutes an attractive candidate for drug delivery. Targeting may occur via the most known interaction of the protein with the neonatal Fc receptor (FcRn). Here, we investigate another HSA delivery path, involving the transferrin receptor, and we elaborate a maghemite-HSA nanohybrid, opening up new opportunities for medical applications. Fluorescence spectrophotometric titration and size-exclusion chromatography were used to substantiate, in cell-free assays, an interaction between HSA and the transferrin receptor R1. This occurs with a dissociation constant, K_D of 6.7 nM. This interaction was confirmed in HeLa cell culture where, by confocal microscopy, rhodamine-labeled HSA is shown to be internalized. HSA was then covalently conjugated onto maghemite nanoparticles (NPs) to give a NP-HSA nanohybrid. The therapeutic potential of this hybrid was demonstrated through its heating capacity in magnetic hyperthermia (MH) and near-infrared (NIR) photothermia (PT). In particular, the Specific Absorption Rate (SAR) in the PT Therapy (PTT) mode, using a 808 nm NIR-LASER (1 W cm^-2) and at iron concentration as low as 2.5 mM, was found to be very high, equal to 1870 W g^-1 with a temperature increment of 9.2 °C. The nanohybrids incubated with HeLa cells were mainly localized at the cell surface. When the PTT mode was applied under the same conditions as in vitro, mortality was higher in HeLa cells than in fibroblasts (non-malignant cells). Cytotoxicity was checked in both cell lines without the PTT mode; the nanohybrids do not seem to affect cell viability. These results make the nanohybrids very promising agents for NIR-PT and for targeting in cancer therapy, since non-malignant cells were not damaged.

T cell receptor repertoires after adoptive transfer of expanded allogeneic regulatory T cells

Regulatory T cell (T_reg ) therapy has been exploited in autoimmune disease, solid organ transplantation and in efforts to prevent or treat graft-versus-host disease (GVHD). However, our knowledge on the in-vivo persistence of transfused T_reg is limited. Whether T_reg transfusion leads to notable changes in the overall T_reg repertoire or whether longevity of T_reg in the periphery is restricted to certain clones is unknown. Here we use T cell receptor alpha chain sequencing (TCR-α-NGS) to monitor changes in the repertoire of T_reg upon polyclonal expansion and after subsequent adoptive transfer. We applied TCR-α-NGS to samples from two patients with chronic GVHD who received comparable doses of stem cell donor derived expanded T_reg . We found that in-vitro polyclonal expansion led to notable repertoire changes in vitro and that T_reg cell therapy altered the peripheral T_reg repertoire considerably towards that of the infused cell product, to different degrees, in each patient. Clonal changes in the peripheral blood were transient and correlated well with the clinical parameters. We suggest that T cell clonotype analyses using TCR sequencing should be considered as a means to monitor longevity and fate of adoptively transferred T cells.

Epidemiological cut-off values for Flavobacterium psychrophilum MIC data generated by a standard test protocol

Epidemiological cut-off values were developed for application to antibiotic susceptibility data for Flavobacterium psychrophilum generated by standard CLSI test protocols. The MIC values for ten antibiotic agents against Flavobacterium psychrophilum were determined in two laboratories. For five antibiotics, the data sets were of sufficient quality and quantity to allow the setting of valid epidemiological cut-off values. For these agents, the cut-off values, calculated by the application of the statistically based normalized resistance interpretation method, were ≤16 mg L(-1) for erythromycin, ≤2 mg L(-1) for florfenicol, ≤0.025 mg L(-1) for oxolinic acid (OXO), ≤0.125 mg L(-1) for oxytetracycline and ≤20 (1/19) mg L(-1) for trimethoprim/sulphamethoxazole. For ampicillin and amoxicillin, the majority of putative wild-type observations were 'off scale', and therefore, statistically valid cut-off values could not be calculated. For ormetoprim/sulphadimethoxine, the data were excessively diverse and a valid cut-off could not be determined. For flumequine, the putative wild-type data were extremely skewed, and for enrofloxacin, there was inadequate separation in the MIC values for putative wild-type and non-wild-type strains. It is argued that the adoption of OXO as a class representative for the quinolone group would be a valid method of determining susceptibilities to these agents.

Thermosensitivity profile of malignant glioma U87-MG cells and human endothelial cells following γ-Fe2O3NPs internalization and magnetic field application

In this study the thermosensitivity of malignant glioblastoma cells (U87-MG), incubated with superparamagnetic 10 nm sized polyol-made γ-Fe₂O₃particles and exposed to an alternating magnetic field (700 kHz, 23.10 kA m⁻¹) for 1 hour, is evidenced.

Design of magnetic molecularly imprinted polymer nanoparticles for controlled release of doxorubicin under an alternative magnetic field in athermal conditions

An innovative magnetic delivery nanomaterial for triggered cancer therapy showing active control over drug release by using an alternative magnetic field is proposed. In vitro and In vivo release of doxorubicin (DOX) were investigated and showed a massive DOX release under an alternative magnetic field without temperature elevation of the medium.

Magnetic engineering of stable rod-shaped stem cell aggregates: circumventing the pitfall of self-bending

A current challenge for tissue engineering while restoring the function of diseased or damaged tissue is to customize the tissue according to the target area. Scaffold-free approaches usually yield spheroid shapes with the risk of necrosis at the center due to poor nutrient and oxygen diffusion. Here, we used magnetic forces developed at the cellular scale by miniaturized magnets to create rod-shaped aggregates of stem cells that subsequently matured into a tissue-like structure. However, during the maturation process, the tissue-rods spontaneously bent and coiled into sphere-like structures, triggered by the increasing cell-cell adhesion within the initially non-homogeneous tissue. Optimisation of the intra-tissular magnetic forces successfully hindered the transition, in order to produce stable rod-shaped stem cells aggregates.

The relative merits of cord blood as a cell source for autologous T regulatory cell therapy in type 1 diabetes

Cord blood has been used as a cell source for therapeutic purposes in children with type 1 diabetes and other disorders. Here, we explore the benefits of cord blood as an autologous source of T regulatory cells for immune cell therapy in patients. CD4(+)CD25(+) T regulatory cells were isolated from cord blood and adult peripheral blood of healthy donors and compared during and after expansion in a 14-day protocol incorporating anti-CD3/anti-CD28 beads, and IL-2 with or without rapamycin. Cord blood T regulatory cells were largely naïve (89±7 vs. 31±10% in young adults, p<0.0001), and had higher expansion yields (median 5,968-fold) than adult T regulatory cells (median 516-fold, p=0.001) and adult naïve T regulatory cells (median 820-fold, p=0.003). Rapamycin reduced expansion yields, but was not necessary to obtain pure expanded cord blood T regulatory cells as judged by FOXP3 staining (94±3%), methylation status of FOXP3 (97%), and intracellular effector cytokine staining (< 6%). Expanded adult T regulatory cells were much less pure in the absence of rapamycin (72±19% FOXP3; 76% by methylation status, <13% INF-γ, <16% IL-4, <5% IL-17 positive), but purity was achieved by inclusion of rapamycin during expansion. Despite differences in purity, all preparations of expanded T regulatory from all sources were able to strongly suppress proliferation of T effector cells in vitro. Our findings suggest that cord blood is an excellent source of T regulatory cells for expansion and autologous cell therapy that may be considered as a strategy to prevent immune-mediated destruction of beta cells in type 1 diabetes.

Magnetically shaped cell aggregates: from granular to contractile materials

In recent decades, significant advances have been made in the description and modelling of tissue morphogenesis. By contrast, the initial steps leading to the formation of a tissue structure, through cell-cell adhesion, have so far been described only for small numbers of interacting cells. Here, through the use of remote magnetic forces, we succeeded at creating cell aggregates of half million cells, instantaneously and for several cell types, not only those known to form spheroids. This magnetic compaction gives access to the cell elasticity, found in the range of 800 Pa. The magnetic force can be removed at any time, allowing the cell mass to evolve spontaneously thereafter. The dynamics of contraction of these cell aggregates just after their formation (or, in contrast, their spreading for non-interacting monocyte cells) provides direct information on cell-cell interactions and allows retrieving the adhesion energy, in between 0.05 and 2 mJ m(-2), depending on the cell type tested, and in the case of cohesive aggregates. Thus, we show, by probing a large number of cell types, that cell aggregates behave like complex materials, undergoing a transition from a wet granular to contractile network, and that this transition is controlled by cell-cell interactions.

IGRP and insulin vaccination induce CD8+ T cell-mediated autoimmune diabetes in the RIP-CD80GP mouse

Autoimmune diabetes is characterized by autoantigen-specific T cell-mediated destruction of pancreatic islet beta cells, and CD8(+) T cells are key players during this process. We assessed whether the bitransgenic RIP-CD80 x RIP-LCMV-GP (RIP-CD80GP) mice may be a versatile antigen-specific model of inducible CD8(+) T cell-mediated autoimmune diabetes. Antigen-encoding DNA, peptide-loaded dendritic cells and antigen plus incomplete Freund's adjuvant were used for vaccination. Of 14 pancreatic proteins tested by DNA vaccination, murine pre-proinsulin 2 (100% of mice; median time after vaccination, 60 days) and islet-specific glucose-6-phosphatase catalytic subunit-related protein (IGRP) (77%, 58 days) could induce diabetes. Vaccination with DNA encoding for zinc transporter 8, Ia-2, Ia-2β, glutamic acid decarboxylase 67 (Gad67), chromogranin A, insulinoma amyloid polypeptide and homeobox protein Nkx-2.2 induced diabetes development in 25-33% of mice. Vaccination with DNA encoding for Gad65, secretogranin 5, pancreas/duodenum homeobox protein 1 (Pdx1), carboxyl ester lipase, glucagon and control hepatitis B surface antigen (HBsAg) induced diabetes in <20% of mice. Diabetes induction efficiency could be increased by DNA vaccination with a vector encoding a ubiquitin-antigen fusion construct. Diabetic mice had florid T cell islet infiltration. CD8(+) T cell targets of IGRP were identified with a peptide library-based enzyme-linked immunospot assay, and diabetes could also be induced by vaccination with major histocompatibility complex (MHC) class I-restricted IGRP peptides loaded on mature dendritic cells. Vaccination with antigen plus incomplete Freund's adjuvant, which can prevent diabetes in other models, led to rapid diabetes development in the RIP-CD80GP mouse. We conclude that RIP-CD80GP mice are a versatile model of antigen specific autoimmune diabetes and may complement existing mouse models of autoimmune diabetes for evaluating CD8(+) T cell-targeted prevention strategies.

Adaptation of innate lymphoid cells to a micronutrient deficiency promotes type 2 barrier immunity

How the immune system adapts to malnutrition to sustain immunity at barrier surfaces, such as the intestine, remains unclear. Vitamin A deficiency is one of the most common micronutrient deficiencies and is associated with profound defects in adaptive immunity. Here, we found that type 3 innate lymphoid cells (ILC3s) are severely diminished in vitamin A-deficient settings, which results in compromised immunity to acute bacterial infection. However, vitamin A deprivation paradoxically resulted in dramatic expansion of interleukin-13 (IL-13)-producing ILC2s and resistance to nematode infection in mice, which revealed that ILCs are primary sensors of dietary stress. Further, these data indicate that, during malnutrition, a switch to innate type 2 immunity may represent a powerful adaptation of the immune system to promote host survival in the face of ongoing barrier challenges.

Thermostability of seven hepatitis C virus genotypes in vitro and in vivo

Hepatitis C virus (HCV) is transmitted primarily through percutaneous exposure to contaminated blood especially in healthcare settings and among people who inject drugs. The environmental stability of HCV has been extrapolated from studies with the bovine viral diarrhoea virus or was so far only addressed with HCV genotype 2a viruses. The aim of this study was to compare the environmental and thermostability of all so far known seven HCV genotypes in vitro and in vivo. Incubation experiments at room temperature revealed that all HCV genotypes showed similar environmental stabilities in suspension with viral infectivity detectable for up to 28 days. The risk of HCV infection may not accurately be reflected by determination of HCV RNA levels. However, viral stability and transmission risks assessed from in vitro experiments correlated with viral infectivity in transgenic mice containing human liver xenografts. A reduced viral stability for up to 2 days was observed at 37 °C with comparable decays for all HCV genotypes confirmed by thermodynamic analysis. These results demonstrate that different HCV genotypes possess comparable stability in the environment and that noninfectious particles after incubation in vitro do not cause infection in an HCV in vivo model. These findings are important for estimation of HCV cross-transmission in the environment and indicate that different HCV genotypes do not display an altered stability or resistance at certain temperatures.

Use of magnetic forces to promote stem cell aggregation during differentiation, and cartilage tissue modeling

Magnetic forces induce cell condensation necessary for stem cell differentiation into cartilage and elicit the formation of a tissue-like structure: Magnetically driven fusion of aggregates assembled by micromagnets results in the formation of a continuous tissue layer containing abundant cartilage matrix.

[Hip ultrasound screening in Mongolia: a Swiss Mongolian Pediatric Project]

To defect incidence of development hip dysplasia by hip ultrasound and to determine efficacy of early treatment: a pilot study in Ulan Bator, Mongolia. Until recently, in Mongolia, early detection and treatment of DDH (developmental dysplasia of the hip) in the first months of life was not possible. A high prevalence as well as a large number of false positive cases indicate an important burden of disease. Since 2009, a project based on ultrasound method of Reinhard Graf is being run by a swiss-mongolian cooperation. A large study including more than 8000 newborns proved, that trained neonatologists are well able to run an ultrasound hip screening. DDH can be detected in the first days after birth and early treatment with a flexion - abduction splint could not only prevent dislocation, but also ensure the maturation process.

Pharmacokinetics of tildipirosin in porcine plasma, lung tissue, and bronchial fluid and effects of test conditions on in vitro activity against reference strains and field isolates of Actinobacillus pleuropneumoniae

The pharmacokinetics of tildipirosin (Zuprevo(®) 40 mg/mL solution for injection for pigs), a novel 16-membered-ring macrolide for the treatment for swine respiratory disease (SRD), was investigated in studies collecting blood plasma and postmortem samples of lung tissue and bronchial fluid (BF) from swine. In view of factors influencing the in vitro activity of macrolides, and for the interpretation of tildipirosin pharmacokinetics in relation to minimum inhibitory concentrations (MIC), additional experiments were conducted to study the effects of pH, carbon dioxide-enriched atmosphere, buffers, and serum on tildipirosin MICs for various reference strains and Actinobacillus (A.) pleuropneumoniae field isolates. After single intramuscular (i.m.) injection at 4 mg/kg body weight, maximum plasma concentration (Cmax) was 0.9 μg/mL observed within 23 min (Tmax ). Mean residence time from the time of dosing to the time of last measurable concentration (MRTlast) and terminal half-life (T1/2) both were about 4 days. A dose-response relationship with no significant sex effect is observed for area under the plasma concentration-time curve from time 0 to the last sampling time with a quantifiable drug concentration (AUClast) over the range of doses up to 6 mg/kg. However, linear dose proportionality could not be proven with statistical methods. The time-concentration profile of tildipirosin in BF and lung far exceeded that in blood plasma. In lung, tildipirosin concentrations reached 3.1 μg/g at 2 h, peaked at 4.3 μg/g at day 1, and slowly declined to 0.8 μg/g at day 17. In BF, tildipirosin levels were 14.3, 7.0, and 6.5 μg/g at days 5, 10, and 14. T1/2 in lung was ∼7 days. Tildipirosin is rapidly and extensively distributed to the respiratory tract followed by slow elimination. Culture media pH and carbon dioxide-enriched atmosphere (CO2 -EA) had a marked impact on in vitro activity of tildipirosin in reference strains of various rapidly growing aerobic and fastidious bacteria including Histophilus (H.) somni ATCC 700025 and A. pleuropneumoniae ATCC 27090. For A. pleuropneumoniae ATCC 27090 testing conditions without CO2 -EA resulted in reduced acidification of culture media pH and a reduction in the minimum inhibitory concentrations compared to standard in vitro test conditions by 2 log2 dilution steps (4-fold) from 8 to 2 μg/mL. Supplementary buffering of standard culture media resulted in a reduction in the A. pleuropneumoniae (n = 8) MIC range by 4 log2 dilution steps (16-fold) from 8-16 to 0.5-1 μg/mL. Incremental supplementation of culture media with 50% serum resulted in noticeable shifts to lower minimum or maximum MICs by at least 2 log2 dilution steps (≥4-fold) in all aerobic and fastidious reference strains tested except for Pasteurella (P.) multocida. The MIC of A. pleuropneumoniae ATCC 27090 decreased by 2-4 log2 dilution steps (4 to 16-fold) from 8 to 0.5-2 μg/mL when 50% serum was added to the standard assay. Considering a higher presence of serum and the rather neutral pH conditions maintained in vivo, it is suggested to take the influence of these factors on in vitro activity into account when interpreting tildipirosin MICs for A. pleuropneumoniae in relation to pharmacokinetics.

The life cycle of the amoeboid alga Synchroma grande (Synchromophyceae, Heterokontophyta)--highly adapted yet equally equipped for rapid diversification in benthic habitats

Synchroma grande (Synchromophyceae, Heterokontophyta) is a marine amoeboid alga, which was isolated from a benthic habitat. This species has sessile cell stages (amoeboid cells with lorica and cysts) and non-sessile cell stages (migrating and floating amoebae) during its life cycle. The different cell types and their transitions within the life cycle are described, as are their putative functions. Cell proliferation was observed only in cells attached to the substrate but not in free-floating or migrating cells. We also characterised the phagotrophy of the meroplasmodium in comparison to other amoeboid algae and the formation of the lorica. The functional adaptations of S. grande during its life cycle were compared to the cell stages of other amoeboid algae of the red and green chloroplast lineages. S. grande was found to be highly adapted to the benthic habitat. One sexual and two asexual reproductive strategies (haplo-diploid life cycle) support the ability of this species to achieve rapid diversification and high adaptivity in its natural habitat.

Multiple malignant diseases in a patient with Rothmund-Thomson syndrome with RECQL4 mutations: Case report and literature review

RECQL4 mutations cause genetic instability and increase the risk of malignant disease. We report on a patient with compound heterozygosity for two novel RECQL4 mutations: mutation c.1919_1924delTCACAG, p.L640_A642delinsP in exon 12 of the RECQL4 gene and mutation c.1704+1G>A in intron 10 of the RECQL4 gene. He subsequently developed large cell anaplastic T cell lymphoma at the age of 9 years, diffuse large cell B lymphoma and osteosarcoma when he was 14 years old, and finally acute lymphatic leukemia when he was 21 years old. The most remarkable clinical features are young age, spontaneous remission of diffuse large cell lymphoma, and severe CNS and skin toxicity of cytotoxic treatment.

Treatment of septicaemia and severe bacterial infections in foals with a new cefquinome formulation: a field study

A multicentre field study was conducted in accordance with VICH Guideline on Good Clinical Practice (VICH 2000) to confirm the efficacy and safety of a new formulation of cefquinome for the treatment of naturally occurring severe bacterial infections and septicaemia in foals. Thirty-nine foals suffering from severe bacterial infections (such as pneumonia, gastro-enteritis, arthritis, omphalitis, or wound infections) or acute septicaemia were treated twice daily with the test product (1 mg cefquinome/kg body weight) intravenously for three days and then intramuscularly for three to 11 days. Investigators examined the foals daily and scored both systemic and local clinical signs to assess the response to treatment, treatment success and relapses. On the day of inclusion a blood sample was taken from each foal for IgG determination and blood culture. In case of abnormal clinical findings additional samples were taken for bacteriology. Treatment was successful in 87.2% of cases (34 of 39 foals) and no relapses were observed. The average duration of treatment was 7.5 days. At inclusion, bacterial culture was positive in 40.5% (15 out of 37) of the blood cultures. Escherichia coli, Clostridium perfringens and Staphylococcus spp. were the most common isolates and were all susceptible to cefquinome. E. coli predominated in swabs from umbilical and open wound infections, and in rectal swabs E. coli. There was no correlation between IgG at inclusion and study outcome or treatment duration. The test product was very well tolerated by all of the foals following intravenous and intramuscular injection. The cefquinome formulation tested was effective and safe in the treatment of severe bacterial infections and septicaemia in foals under field conditions.

Exploring the genetic link between RLS and ADHD

Attention deficit/hyperactivity disorder (ADHD) is a highly heritable neurodevelopmental disorder of childhood onset. Clinical and biological evidence points to shared common central nervous system (CNS) pathology of ADHD and restless legs syndrome (RLS). It was hypothesized that variants previously found to be associated with RLS in two large genome-wide association studies (GWA), will also be associated with ADHD. SNPs located in MEIS1 (rs2300478), BTBD9 (rs9296249, rs3923809, rs6923737), and MAP2K5 (rs12593813, rs4489954) as well as three SNPs tagging the identified haplotype in MEIS1 (rs6710341, rs12469063, rs4544423) were genotyped in a well characterized German sample of 224 families comprising one or more affected sibs (386 children) and both parents. We found no evidence for preferential transmission of the hypothesized variants to ADHD. Subsequent analyses elicited nominal significant association with haplotypes consisting of the three SNPs in BTBD9 (chi2 = 14.8, df = 7, nominal p = 0.039). According to exploratory post hoc analyses, the major contribution to this finding came from the A-A-A-haplotype with a haplotype-wise nominal p-value of 0.009. However, this result did not withstand correction for multiple testing. In view of our results, RLS risk alleles may have a lower effect on ADHD than on RLS or may not be involved in ADHD. The negative findings may additionally result from genetic heterogeneity of ADHD, i.e. risk alleles for RLS may only be relevant for certain subtypes of ADHD. Genes relevant to RLS remain interesting candidates for ADHD; particularly BTBD9 needs further study, as it has been related to iron storage, a potential pathophysiological link between RLS and certain subtypes of ADHD.

[Hereditary Alzheimer's disease with amyloid angiopathy caused by amyloid precursor protein locus]

We report a patient with early-onset autosomal dominant dementia. The CSF showed increased levels of tau protein and decreased amyloid beta (ratio 42:40) typical for Alzheimer's disease. Cerebral MRI revealed vascular lesions and white-matter changes around the posterior horns of the ventricles with only moderate atrophy of the brain. Susceptibility-weighted imaging detected multiple small hemorrhagic changes. Gene analysis revealed amyloid precursor protein (APP) locus duplication as the cause of hereditary Alzheimer's dementia. The co-occurrence of CSF changes typical for Alzheimer's disease and MRI findings of cerebral amyloid angiopathy is remarkable, as it is also described for APP locus duplication. In conjunction with a family history suggestive of hereditary dementia, such a constellation should lead to enhanced gene analysis.