Structural connections between the noradrenergic and cholinergic system shape the dynamics of functional brain networks.

Complex cognitive abilities are thought to arise from the ability of the brain to adaptively reconfigure its internal network structure as a function of task demands. Recent work has suggested that this inherent flexibility may in part be conferred by the widespread projections of the ascending arousal systems. While the different components of the ascending arousal system are often studied in isolation, there are anatomical connections between neuromodulatory hubs that we hypothesise are crucial for mediating key features of adaptive network dynamics, such as the balance between integration and segregation. To test this hypothesis, we estimated the strength of structural connectivity between key hubs of the noradrenergic and cholinergic arousal systems (the locus coeruleus [LC] and nucleus basalis of Meynert [nbM], respectively). We then asked whether the strength of structural LC and nbM inter-connectivity was related to individual differences in the emergent, dynamical signatures of functional integration measured from resting state fMRI data, such as network and attractor topography. We observed a significant positive relationship between the strength of white-matter connections between the LC and nbM and the extent of network-level integration following BOLD signal peaks in LC relative to nbM activity. In addition, individuals with denser white-matter streamlines interconnecting neuromodulatory hubs also demonstrated a heightened ability to shift to novel brain states. These results suggest that individuals with stronger structural connectivity between the noradrenergic and cholinergic systems have a greater capacity to mediate the flexible network dynamics required to support complex, adaptive behaviour. Furthermore, our results highlight the underlying static features of the neuromodulatory hubs can impose some constraints on the dynamic features of the brain.

Generation of an equine biobank to be used for Functional Annotation of Animal Genomes project.

The Functional Annotation of Animal Genomes (FAANG) project aims to identify genomic regulatory elements in both sexes across multiple stages of development in domesticated animals. This study represents the first stage of the FAANG project for the horse, Equus caballus. A biobank of 80 tissue samples, two cell lines and six body fluids was created from two adult Thoroughbred mares. Ante-mortem assessments included full physical examinations, lameness, ophthalmologic and neurologic evaluations. Complete blood counts and serum biochemistries were also performed. At necropsy, in addition to tissue samples, aliquots of serum, ethylenediaminetetraacetic acid (EDTA) plasma, heparinized plasma, cerebrospinal fluid, synovial fluid, urine and microbiome samples from all regions of the gastrointestinal and urogenital tracts were collected. Epidermal keratinocytes and dermal fibroblasts were cultured from skin samples. All tissues were grossly and histologically evaluated by a board-certified veterinary pathologist. The results of the clinical and pathological evaluations identified subclinical eosinophilic and lymphocytic infiltration throughout the length of the gastrointestinal tract as well as a mild clinical lameness in both animals. Each sample was cryo-preserved in multiple ways, and nuclei were extracted from selected tissues. These samples represent the first published systemically healthy equine-specific biobank with extensive clinical phenotyping ante- and post-mortem. The tissues in the biobank are intended for community-wide use in the functional annotation of the equine genome. The use of the biobank will improve the quality of the reference annotation and allow all equine researchers to elucidate unknown genomic and epigenomic causes of disease.

Unified neural field theory of brain dynamics underlying oscillations in Parkinson's disease and generalized epilepsies.

The mechanisms underlying pathologically synchronized neural oscillations in Parkinson's disease (PD) and generalized epilepsies are explored in parallel via a physiologically-based neural field model of the corticothalamic-basal ganglia (CTBG) system. The basal ganglia (BG) are approximated as a single effective population and their roles in the modulation of oscillatory dynamics of the corticothalamic (CT) system and vice versa are analyzed. In addition to normal EEG rhythms, enhanced activity around 4 Hz and 20 Hz exists in the model, consistent with the characteristic frequencies observed in PD. These rhythms result from resonances in loops formed between the BG and CT populations, analogous to those that underlie epileptic oscillations in a previous CT model, and which are still present in the combined CTBG system. Dopamine depletion is argued to weaken the dampening of these loop resonances in PD, and network connections then explain the significant coherence observed between BG, thalamic, and cortical population activity around 4-8 Hz and 20 Hz. Parallels between the afferent and efferent connection sites of the thalamic reticular nucleus (TRN) and BG predict low dopamine to correspond to a reduced likelihood of tonic-clonic (grand mal) seizures, which agrees with experimental findings. Furthermore, the model predicts an increased likelihood of absence (petit mal) seizure resulting from pathologically low dopamine levels in accordance with experimental observations. Suppression of absence seizure activity is demonstrated when afferent and efferent BG connections to the CT system are strengthened, which is consistent with other CTBG modeling studies. The BG are demonstrated to have a suppressive effect on activity of the CTBG system near tonic-clonic seizure states, which provides insight into the reported efficacy of current treatments in BG circuits. Sleep states of the TRN are also found to suppress pathological PD activity in accordance with observations. Overall, the findings demonstrate strong parallels between coherent oscillations in generalized epilepsies and PD, and provide insights into possible comorbidities.

[Defect coverage with myofasciocutaneous free flaps. Consequence of corticosteroid infiltration of the wrist in a patient on immunosuppressive therapy]. / Defektdeckung mit myofasziokutanem Lappen. Folge einer Kortikoidinfiltration des Handgelenks bei einer immunsuppressiv behandelten Patientin.

Intra-articular corticosteroid injection and radiation of the wrist was performed in a patient on immunosuppressive therapy. She sustained empyema and impending compartment syndrome. After fasciotomy, debridement and antibiotic therapy had been performed, we provided soft tissue coverage by a combined ALTP and muscular free flap on the vascular trunk of the descending branch of the lateral circumflex femoral artery. There were no complications and the patient is very satisfied with the outcome.

[Reconstruction of the elbow with the deep circumflex iliac artery. Multicomponent free flap plasty after a gunshot wound]. / Rekonstruktion des Ellenbogens durch eine A. circumflexa iliaca profunda. Mehrkomponentenlappenplastik nach einer Schussverletzung.

A 20-year-old woman sustained massive elbow trauma from a gunshot wound. After initial surgery soft tissue coverage, reconstruction of the proximal third of the ulna, of the ulnar collateral ligament and of the triceps tendon was performed by one multicomponent microvascular free flap. There were no complications, the elbow is stable and reached full weight bearing 11 months after trauma. Active range of motion for extension and flexion is 0-20°-80°.

A comprehensive test system to identify suitable antibodies against p53 for immunohistochemical analysis of canine tissues.

The tumour suppressor p53 is commonly detected in tissues of companion animals by means of antibodies raised against the human protein. The following three-step procedure was devised to test the suitability of such antibodies for immunohistochemistry on canine tissues. (1) Western blot and immunohistochemical analyses on bacterially expressed recombinant canine protein to assess human-to-canine cross-reactivity. (2) Immunohistochemistry of cultured, UVB-irradiated canine keratinocytes to evaluate suitability for detection of endogenous p53. (3) Immunohistochemistry on tissue arrays to further substantiate suitability of the antibodies on a panel of normal and neoplastic human and canine tissues. Five of six antibodies cross-reacted with recombinant canine p53. Three of these (PAb122, PAb240, CM-1) also immunolabelled stabilized wild type p53 in cell cultures and elicited a consistent, characteristic labelling pattern in a subset of tumours. However, two alternative batches of polyclonal antibody CM-1 failed to detect p53 in cell cultures, while showing a characteristic labelling pattern of a completely different subset of tumours and unspecific labelling of normal tissues. The test system described is well suited to the selection of antibodies for immunohistochemical p53 detection. The results emphasize the need to include appropriate controls, especially for polyclonal antibodies.

[Avascular necrosis of the capitate in athletes]. / Die avaskuläre Kapitatumnekrose bei Sportlern.

The possibility of osteonecrosis of the carpal bones should always be considered when athletes present with pain of unknown origin in the hand and wrist, in particular, if they are participating in sports such as gymnastics or weight-lifting that involve extreme loading of the wrist with axial compression and microtrauma. This sort of extreme loading of the wrist combined with a constitutionally "weak" blood supply to the individual carpal bones may lead to the formation of osteo-necrotic zones. A treatment method that can produce excellent results, depending on the pathomorphology, is available in the form of vascularized bone grafting.

Expression of neural cell adhesion molecule-related sialoglycoprotein in small cell lung cancer and neuroblastoma cell lines H69 and CHP-212.

Monoclonal antibodies (MAbs) 123C3 and 123A8 generated against a membrane preparation of a small cell lung carcinoma (SCLC) specimen recognize not only SCLC and bronchial carcinoids but also a significant portion of non-small cell lung carcinomas (non-SCLC) of various histological types. Together with 13 other monoclonal antibodies, which show preference for SCLC, they have been ranked as SCLC cluster 1 (SC-1) Mabs. In this study we show that SC-1 MAbs are directed against a restricted number of epitopes, and that SC-1 MAbs and a polyclonal antiserum directed against the neural cell adhesion molecule (NCAM) recognize identical glycoproteins, indicating that SC-1 antigens are closely related to or identical with NCAM. Long polysialic acid units composed of alpha-(2,8)-linked N-acetylneuraminic acid units, which in mammals are found exclusively on NCAM, were present on SC-1 antigens in SCLC. This provides further evidence that SC-1 MAbs recognize NCAM. The SC-1 antigens in the SCLC cell line H69 were present in two forms, NCAM-containing alpha-(2,8)-polysialic acid units identified by antiserum 735, the NCAM-H form, and the less sialylated NCAM-L form. The NCAM-H form consisted of diffusely migrating sialoglycoproteins with a molecular weight of 200,000-250,000, which resolved after neuraminidase treatment into two proteins with molecular weights of 140,000 and 180,000. Since the NCAM-H form is expressed in the lung tumor type with a poor prognosis, our results suggest that NCAM might be implicated in the invasive behavior of these NCAM-positive lung tumors.

Activation of the fibrinolytic system during intracoronary streptokinase administration.

Serial biochemical studies were performed in 12 patients treated with intracoronary streptokinase infusion for acute myocardial infarction, in order to study the method of activation of the fibrinolytic system during local administration of a relatively low dose of this drug and to determine correlations between systemic effects and reperfusion. Plasma samples were obtained before and every 15 minutes during the infusion of streptokinase and after completion of the therapy. Streptokinase dosage in this study was 211,000 +/- 88,000 IU (+/- SD). The average time from the onset of symptoms to the start of infusion was 2 hours 50 minutes (range 1 hour 10 minutes to 3 hours 30 minutes). Reperfusion occurred in six patients and temporary recanalization in three; in three patients no recanalization was achieved. Fibrinolytic assays of pretreatment plasma samples revealed elevated levels of plasminogen activators, presumably caused by the release of tissue-type plasminogen activator after a condition of stress. Plasminogen concentrations decreased from 94 +/- 17% to 44 +/- 30%. Alpha 2-antiplasmin fell from 84 +/- 27% to 12 +/- 19%; in seven patients no plasmin inhibitor activity was measurable at the completion of the infusion. Free plasmin occurred in samples only when this inhibitor had disappeared. This resulted in a lytic state leading to degradation of fibrinogen, the levels of which fell from 2.9 +/- 0.7% to 1.5 +/- 1.1%. Fibrinogen degradation products, measured in plasma with monoclonal antibodies, increased exponentially during streptokinase infusion in at least four patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Hepatocyte growth factor/scatter factor (HGF/SF) is produced by human bone marrow stromal cells and promotes proliferation, adhesion and survival of human hematopoietic progenitor cells (CD34+).

The fate of hematopoietic progenitor cells (HPCs) in the bone marrow (BM) microenvironment is determined by two different interactions: 1) they adhere (via integrins) to both extracellular matrix molecules and BM stromal cells; and 2) stromal cells produce cytokines that influence their survival, proliferation, differentiation, and mobilization. The ligands for the protein tyrosine kinase receptors c-KIT and FLT3/FLK2, stem cell factor (SCF), and FL are produced by BM stromal cells and are known to affect several facets of hematopoiesis. We studied another protein tyrosine kinase receptor, c-MET, and its ligand hepatocyte growth factor (HGF), also known as scatter factor (SF), which play a similar role in hematopoiesis. c-MET mRNA is expressed in immature human BM HPCs (CD34+CD33- or CD34+CD38-), but not in more mature HPCs (CD34+CD33+ or CD34+CD38+). The ligand HGF/SF is predominantly produced by BM stromal cells at both the mRNA and protein levels. We confirmed functionally that HGF/SF alone has no effect on proliferation of HPCs, but that when combined with granulocyte/macrophage colony-stimulating factor (GM-CSF) or interleukin-3 it acts as a synergistic proliferative factor, although not as potently as kit-ligand or FLT-3/FLK-2 ligand. Furthermore, HGF/SF promotes adhesion of HPCs to immobilized fibronectin. HGF/SF-induced adhesion to fibronectin is probably caused by activation of the integrins alpha4beta1 and alpha5beta1, insofar as we were able to block this interaction by using monoclonal blocking antibodies directed against these integrin subunits. Addition of the tyrosine-phosphorylation inhibitor genistein inhibited HGF/SF-induced adhesion, supporting the idea that HGF/SF-induced effects are the result of signaling via the receptor c-MET after ligand binding. The enhanced adhesion of HGF/SF to fibronectin proved to be beneficial for the maintenance of the colony-forming potential of HPCs. HGF/SF alone and especially in combination with fibronectin prolongs survival of GM colony-forming cells in liquid culture. Our data indicate that HGF/SF is a polyfunctional cytokine in the BM microenvironment. It is produced by human BM stromal cells and directly or indirectly promotes proliferation, adhesion, and survival of human HPCs.

Cyclopentenyl cytosine inhibits cytidine triphosphate synthetase in paediatric acute non-lymphocytic leukaemia: a promising target for chemotherapy.

Cytidine triphosphate (CTP) synthetase is a key enzyme in the anabolic pathways of cytosine and uracil ribonucleotide metabolism. The enzyme catalyses the conversion of uridine triphosphate (UTP) into CTP, and has a high activity in various malignancies, which has led to the development of inhibitors of CTP synthetase for therapeutic purposes. We studied both CTP synthetase activity and ribonucleotide concentrations in leukaemic cells of 12 children suffering from acute non-lymphocytic leukaemia (ANLL), and performed incubation experiments with cyclopentenyl cytosine (CPEC), a nucleoside analogue that is capable of inhibiting CTP synthetase. The CTP synthetase activity in ANLL cells (5.1+/-2.3 nmol CTP/mg/h) was significantly higher compared with granulocytes of healthy controls (0.6+/-0.4 nmol CTP/mg/h, P=0.0002), but was not different from the CTP synthetase activity in non-malignant CD34+ bone marrow cells (5. 6+/-2.4 nmol CTP/mg/h). Major shifts were observed in the various ribonucleotide concentrations in ANLL cells compared with granulocytes: the absolute amount of ribonucleotides was increased with a substantial rise of the CTP (2.4 versus 0.4 pmol/microg protein, P=0.0007) and UTP (8.7 versus 1.6 pmol/microg protein, P=0. 0007) concentrations in ANLL cells compared with granulocytes. Treatment of ANLL cells in vitro with CPEC induced a major depletion (77% with 2.5 microM of CPEC) in the concentration of CTP, whilst the concentrations of the other ribonucleotides remained unchanged. Therefore, the high activity of CTP synthetase in acute non-lymphocytic leukaemic cells can be inhibited by CPEC, which provides a key to a new approach for the treatment of ANLL.

Role of subtilisin-like convertases in cadherin processing or the conundrum to stall cadherin function by convertase inhibitors in cancer therapy.

Cadherins are a family of intercellular adhesion receptors. Produced as inactive precursors, they become functional adhesion molecules after proteolytic cleavage by subtilisin-like pro-protein convertases (PCs). Owing to their activation and assembly into multiprotein adhesion complexes at sites of cell contacts, adhesion-competent cadherins are prerequisite for tissue integrity. In recent years evidence has accumulated that intercellular junctions not only provide mechanical linkage, but in addition are potent modulators of signalling cascades. This infers a biological role to intercellular adhesion complexes that is significantly more complex and powerful. Currently, the broad implications of disturbances in somatic tissue adhesion components are only just beginning to emerge. Prominent examples of adhesion defects include autoimmune diseases, or tumour invasion and metastasis and malignant transformation. This review reports on our current knowledge of cadherin function and their maturation by pro-protein convertases, and puts special emphasis on the consequences of pro-protein convertase inhibition for epithelial tissue homeostasis.

Arthrodesis of the shoulder after septic arthritis. Long-term results.

We analysed the long-term results of arthrodesis of the shoulder after infection in 15 patients. At the time of operation, 14 cultures were positive for Staphylococcus aureus. The mean follow-up was 8.3 years (3 to 14) and 90% of the patients were satisfied with the outcome. There were complications in five patients (33%); in three there was nonunion with loosening of the implant. One patient had a sound bony union but with a persistent sinus six years after arthrodesis and another had a sinus which healed after the metal was removed. Four of these five patients (80%) were heavy smokers (> 20 cigarettes/day). Cancellous bone grafting did not affect the incidence of complications. The mean age of the patients with complications was 58.6 v 48.6 years for those without (p = 0.2808; not significant). Those with complications had had more previous operations (6.4 v 2.5, p < 0.05). Antibiotics, as determined by the bacteriological cultures, were administered for six weeks. The complication rate was higher in patients with active sepsis but the younger the patient and the fewer number of previous operations (< 50 years, < four previous operations), the better was the outcome. Considering the rate of complications, we recommend early surgery in these patients.

Surgical therapy of post traumatic malalignement and arthrosis of the ankle joint.

Joint incongruency, malalignement as well as degenerative changes of the ankle joint may result in disabling pain with a significant decrease in function and mobility. The clinical symptoms may affect all aspects of life. Primary osteoarthritis of the ankle joint is uncommon, and posttraumatic conditions with significant changes in joint mechanics are usually the primary source of joint degeneration with the resultant clinical symptoms. Apart from pain relief and restoration of joint mobility, prevention of joint degeneration or progression of arthrosis should be the main goal in treating such conditions. Arthrodesis of the ankle still is the method of choice for severe osteoarthritis of the ankle, however several surgical treatment options are available to deal with mild to moderate joint degeneration. Restoration of the anatomy and joint alignement in posttraumatic deformities as well as ligament reconstruction in chronic instability are measurements to prevent developement or progression of osteoarthritis. Joint debridement is useful in primary anterior joint pathology, in advanced osteoarthritis at least temporary pain relief can be achieved. In severe osteoarthritis arthrodesis of the ankle is the method of choice for long-term pain relief and restoration of mobility.

GABA system changes in methylphenidate sensitized female rats.

Methylphenidate (MPD) is a psychostimulant that is prescribed to treat attention-deficit/hyperactivity disorder (ADHD) and has been used as a recreational drug. In animal models, repetitive exposure to methylphenidate can induce a behavioral sensitization. Stimulants are able to change neuronal circuits in the mesolimbic pathway, and the GABA system is one of the most involved neurotransmitter systems in this process. Women represent a risk group for psychostimulant abuse because they respond more strongly, which is probably due to the influence of sex hormones. The objective of the present study was to investigate the influence of sex hormones on behavioral sentsitization and changes to glutamic acid decarboxylase (GDA65 and GDA67) isoenzymes and α2 GABAA receptor subunit mRNA expression in the prefrontal cortex and the striatum of rats, as induced by methylphenidate administration (2.5 mg/kg, i.p.). Female rats were divided into 2 hormonal conditions: ovariectomized and intact group. Repeated methylphenidate treatment led to behavioral sensitization, which was stronger in females with circulating hormones (intact group). The analysis of mRNA levels in the striatum, in both groups, showed a decline in GAD65, but not GAD67, transcription after repeated methylphenidate treatment. In the prefrontal cortex, both GAD65 and GAD67 showed an increase in transcription with repeated methylphenidate treatment. There was no change in the transcription level of α2 GABAA receptor subunits. In conclusion, it was shown that sex hormones were able to modify behavioral sensitization to methylphenidate and the drug affected the GABA system in brain areas known to be involved in the development of drug dependence.

[Semilunar bone necrosis (Kienböck's disease) - first clinical results after free microvascularised bone graft from the distal femur]. / Die idiopathische Mondbeinnekrose (M. Kienböck) - Erste Ergebnisse nach operativer Therapie mit einem freien mikrovaskulären Femurtransplantat.

BACKGROUND: Idiopathic aseptic osseous necrosis of the semilunar bone is also called Kienböck's disease after Robert Kienböck who firstly described this disease. The clinical picture is characterised by a stage-like course. Internationally the classification according to Lichtman and Ross has achieved the most acceptance. The actual therapy is dependent on the present disease stage. Basically, various pressure-relieving operative procedures are possible, on the other hand operative interventions via revascularisation represent a therapeutic option. In the case of advanced disease only, "salvage procedures" like partial or total arthrodesis of the wrist are available. However, such operations are associated with marked restrictions in the range of motion and unsatisfactory clinical results. The present study reports on our clinical experiences after operative therapy for aseptic lunar bone necrosis via free microvascularised bone grafting from the distal femur. PATIENTS AND METHODS: Between 01/2005 and 12/2010 nineteen patients with idiopathic semilunar bone necrosis underwent operative care via a free microvascularised bone graft from the distal femur at our institution. 16 patients could be re-evaluated retrospectively on follow-up examination at 26.5 months (range 16-42) on average after primary care. Mean age was 43.8 years (range 24-66). Clinical assessment was performed according to the Mayo wrist score (MWS) and the disabilities of the arm, shoulder and hand (DASH) score. Radiological assessment was performed according to the classification of Lichtman and Ross. RESULTS: On operative treatment 14 patients were graded II at least according to the Lichtman classification. An additional 2 patients showed a stage III B disease. The median operative time amounted to 254 min (range 233-362). The postoperative course did not reveal any complications, in particular concerning wound healing. Only one patient (6 %) showed no trabecular integration between the inserted graft and the lunar bone. Clinical evaluation according to the MWS with a median of 82.5 points (65-100), and the DASH score with a median of 29.5 points (24.2-102.2) documented good to excellent clinical results. CONCLUSION: Operative treatment for idiopathic semilunar bone necrosis via a free microvascularised bone graft from distal femur achieves good clinical results without an increase of postoperative complications even with advanced stages of the disease. However, long-term results and larger patient samples are required to prove the final success of this operative technique.

Akt promotes chemoresistance in human ovarian cancer cells by modulating cisplatin-induced, p53-dependent ubiquitination of FLICE-like inhibitory protein.

Although Akt is a determinant of cisplatin (cis-diaminedichloroplatinum (CDDP)) resistance in ovarian cancer cells, which is related in part to its inhibitory action on p53 activation, precisely how Akt confers CDDP resistance is unclear. In this study, we show that CDDP induced p53-dependent Fas-associated death domain-like interleukin-1beta-converting enzyme (FLICE)-like inhibitory protein (FLIP) degradation in chemosensitive ovarian cancer cells but not their resistant counterparts. CDDP induced FLIP-p53-Itch interaction, colocalization and FLIP ubiquitination in chemosensitive but not chemoresistant ovarian cancer cells. Moreover, although activated Akt inhibited CDDP-induced FLIP degradation and apoptosis in sensitive cells, these responses were facilitated by dominant-negative Akt expression in chemoresistant cells. Inhibition of Akt function also facilitated p53-FLIP interaction and FLIP ubiquitination, which were attenuated by p53 silencing. These results suggest that Akt confers resistance, in part, by modulating CDDP-induced, p53-dependent FLIP ubiquitination. Understanding the precise etiology of chemoresistance may improve treatment for ovarian cancer.