Modulation of mu opioid receptor desensitization in peripheral sensory neurons by phosphoinositide 3-kinase gamma

G protein-coupled opioid receptors undergo desensitization after prolonged agonist exposure. Recent in vitro studies of mu-opioid receptor (MOR) signaling revealed an involvement of phosphoinositide 3-kinases (PI3K) in agonist-induced MOR desensitization. Here we document a specific role of the G protein-coupled class IB isoform PI3Kgamma in MOR desensitization in mice and isolated sensory neurons. The tail-withdrawal nociception assay evidenced a compromised morphine-induced tolerance of PI3Kgamma-deficient mice compared to wild-type animals. Consistent with a role of PI3Kgamma in MOR signaling, PI3Kgamma was expressed in a subgroup of small-diameter dorsal root ganglia (DRG) along with MOR and the transient receptor potential vanilloid type 1 (TRPV1) receptor. In isolated DRG acute stimulation of MOR blocked voltage-gated calcium currents (VGCC) in both wild-type and PI3Kgamma-deficient DRG neurons. By contrast, following long-term opioid administration the attenuating effect of MOR was strongly compromised in wild-type DRG but not in PI3Kgamma-deficient DRG. Our results uncover PI3Kgamma as an essential modulator of long-term MOR desensitization and tolerance development induced by chronic opioid treatment in sensory neurons.

The measles situation in Austria: a rapid risk assessment by an ECDC team and the outcome of an international meeting in Vienna, Austria

For the last three years, Austria has been considered a low-moderate incidence country (< 1/100,000/year) for measles [1] and the last significant measles outbreak occurred in 2003 involving 64 cases [2].

[Musculoskeletal biomechanics of the knee joint. Principles of preoperative planning for osteotomy and joint replacement]

The long-term clinical outcome of surgical interventions at the knee is dependent upon the quality of the restoration of normal function, together with moderate musculoskeletal loading conditions. In order to achieve this, it is essential to consider biomechanical knowledge during the planning and execution of the procedures. Until now, such knowledge has only been available in books and journal manuscripts and is merely considered during preoperative planning. Its transfer into the specific intraoperative situation is, however, primarily dependent upon the surgeon's skills and understanding. Mathematical models hold the potential to provide the surgeon with detailed, patient-specific information on the in vivo forces, as well as their spatial and temporal distribution. Their application in clinical routine, however, requires a comprehensive validation. Based on a model validated against patient data, it has been shown that - mainly as a result of the action of the muscles - both the tibiofemoral as well as the patellofemoral joints experience substantial mechanical loads even during normal activities of daily living. The calculations further indicate that malalignment at the knee in the frontal plane of more than approximately 4 degrees results in considerably increased forces across the tibiofemoral joint. The actual change in force to a given degree of malalignment might, however, vary greatly between subjects. In order to additionally determine the distribution of the forces in more detail, a sufficiently accurate model of knee joint kinematics is required. In combination with MR-based in vivo imaging techniques, new mathematical models offer the possibility to capture the individual characteristics of knee kinematics and might additionally allow the effect of muscle activity on joint kinematics to be considered. By implementing these technologies in preoperative planning and navigation systems, up-to-date biomechanical knowledge can be made available at the surgeons' fingertips. We propose that optimizing the biomechanical conditions through using these approaches will allow the long-term function of the replaced joint to be significantly enhanced.

A new model to predict in vivo human knee kinematics under physiological-like muscle activation

Although a number of approaches have attempted to model knee kinematics, rarely have they been validated against in vivo data in a larger subject cohort. Here, we assess the feasibility of four-bar linkage mechanisms in addressing knee kinematics and propose a new approach that is capable of accounting for lengthening characteristics of the ligaments, including possible laxity, as well as the internal/external rotation of the joint. MR scans of the knee joints of 12 healthy volunteers were taken at flexion angles of 0 degrees , 30 degrees and 90 degrees under both passive and active muscle conditions. By reconstructing the surfaces at each position, the accuracy of the four-bar linkage mechanism was assessed for every possible combination of points within each cruciate ligament attachment area. The specific set of parameters that minimized the deviation between the predictions and the in vivo pose was derived, producing a mean error of 1.8 and 2.5 on the medial and 1.7 and 2.4mm on the lateral side at 30 degrees and 90 degrees flexion, respectively, for passive motion, significantly improving on the models that did not consider internal/external rotation. For active flexion, mean medial errors were 3.3 and 4.7 mm and lateral errors 3.4 and 4.8 mm. Using this best parameter set, a generic predictive model was created and assessed against the known in vivo positions, producing a maximum average error of 4.9 mm at 90 degrees flexion. The accuracy achieved shows that kinematics may be accurately reconstructed for subject specific musculoskeletal models to allow a better understanding of the load distribution within the knee.

An esophagobronchial fistula caused by an unusual foreign body in the esophagus leading to mediastinitis with fatal outcome

An 8(10)/(12) year old girl with infantile cerebral paresis (ICP), severe mental retardation and seizure disorder was admitted to the intensive care unit (ICU) with clinical signs of aspiration and died ten days later. Final diagnosis was esophagobronchial fistula caused by a foreign body in the esophagus provoking aspiration pneumonia, mediastinitis and respiratory distress syndrome (ARDS). The foreign body was found to be part of a plastic toy. The clinical relevance of aspiration in mentally retarded children and the peculiar nature of the foreign body impacted in the esophagus in this case are discussed. We conclude that in cases of aspiration pneumonia in mentally retarded children the presence of unusual foreign bodies should be suspected.

Molecular epidemiology of West Nile Virus in humans

After the introduction of West Nile Virus into the United States of America in 1999 followed by annual WNV epidemics during the mosquito seasons and spreading of the virus from the East (New York; 1999) to the West of the U.S. (California; 2003/2004) there appeared the question of whether a similar scenario could happen in Europe, too. To be able to answer this question the German Ministry of Health decided to investigate the prevalence and incidence of WNV infections in German blood donors. First a test algorithm was established taking into account the high level of cross-reactivity between different flavivirus infections in serological test systems. AntiWNV-suspicious specimens were further investigated for their neutralisation capacity and by an antiWNV confirmation assay developed in-house. As a preliminary result of our studies a very low prevalence of WNV infections in healthy German blood donors was measured. Development of highly specific test systems is necessary for accurate and reliable differential diagnosis of flavivirus infections.

Magnetic resonance imaging guided corticosteroid injection of sacroiliac joints in patients with spondylarthropathy. Are multiple injections more beneficial?

Efficacy of a second magnetic resonance (MR) imaging guided corticosteroid injection of inflamed sacroiliac joints (SIJ) in patients with spondylarthropathy. Thirty-one patients received 50 injections in an outpatient basis. Fifteen of 31 patients who relapsed or were non-responders received a second injection. All had MR guided injection of 40 mg triamcinolone acetonide into SIJ using an open 0.2 Tesla unit. Twenty of 31 patients after the first injection, and 9 of 15 patients after the second injection reported subjective improvement, which lasted for a mean of 8.7+/-10.9 and 16.1+/-15.8 months for each group. Subchondral bone marrow edema resolved in 15 of 20 patients who reported subjective improvement, after the first injection. No complications occurred. MR guided steroid injection of SIJ is effective and safe. Since there is no exposure to radiation it could be performed many times. Repeated injections seem to be beneficial for primary non-responders and patients who relapsed.

Differenzialdiagnose einer papulösen Hauterkrankung des Neugeborenen: Pemphigoid gestationis

The clinical relevance of bullous skin diseases in newborns varies widely. We present the case of a preterm, 35 weeks of gestation, infant who was admitted to our hospital with skin lesions on face, thorax and plantae. There were no other pathological findings on clinical and neurological examinations. During another pregnancy the mother of the child had already suffered from pemphigoid gestationis. In the blood of the newborn complement-fixing auto-antibodies against BP180, the common antigen of pemphigoid gestationis and bullous pemphigoid, were detected. The skin lesions disappeared after a few days of local antiseptic therapy. Pemphigoid gestations is a rare autoimmune dermatosis in pregnancy. The frequency of skin lesions in newborns of mothers with pemphigoid gestationis is estimated to about 5 -- 10 %.

[Children: improving the prevention and early advancement in children with behavioral- and developmental disorders in the Ennepe-Ruhr District]

Developmental behavioural disorders in early childhood are a serious public health problem, because they signify a higher risk of social, regulatory and emotional impairment in later life. The public health office in Ennepe-Ruhr develops in cooperation with the communities a programme of health promotion for children and their families. An important motive is continually rising costs for supporting children with developmental problems. An element in the programme is a project of counselling mothers with babies and toddlers with excessive crying, serious sleep disorders and anxiety problems. This example of early intervention promises short-term relief, early identification of problem children and the strengthening of parental resources. A key issue is the introduction of a systematic evaluation of all communal funding for measures of support for preschool children. It shows that such measures start relatively late, and the coordination at community level is not always optimal. Some progress has been made, but criteria to measure the efficiency of current health promotion are still lacking. According to public health research early intervention for risk groups (single mothers, migrant families or families depending on public assistance) promises to give children and their families a better social and health perspective in life. It should be a primary health target for communities to develop evidence-based health programmes for children, focussing on mental and social well-being. Studies indicate that such interventions might have positive financial results.

Synaptic congenital myasthenic syndrome in three patients due to a novel missense mutation (T441A) of the COLQ gene

Congenital myasthenic syndromes (CMS) with deficiency of endplate acetylcholinesterase (AChE) are caused by mutations in the synapse specific collagenic tail subunit gene (COLQ) of AChE. We identified a novel missense mutation (T441A) homozygously in three CMS patients from two unrelated German families. The mutation is located in the C-terminal region of the ColQ protein, which initiates assembly of the triple helix, and is essential for insertion of the tail subunit into the basal lamina. Density gradient analysis of AChE extracted from muscle of one of the patients revealed the absence of asymmetric AChE. All patients were characterized by an onset of disease in childhood, exercise-induced proximal weakness, absence of ptosis and ophthalmoparesis, a decremental EMG response, and deterioration in response to anticholinesterase drugs. However, age at onset, disease progression, disease severity, and functional impairment varied considerably among the three patients. As adults, two siblings from one family experience only mild impairment, while the third patient requires a wheelchair for most of the day and assisted ventilation at night.