Altered long-term corticostriatal synaptic plasticity in transgenic mice overexpressing human CU/ZN superoxide dismutase (GLY(93)-->ALA) mutation

Apart from the extensive loss of motor neurons, degeneration of midbrain dopaminergic cells has been described in both familial and sporadic forms of amyotrophic lateral sclerosis (ALS). Mice overexpressing the mutant human Cu/Zn superoxide dismutase (SOD1) show an ALS-like phenotype in that they show a progressive death of motor neurons accompanied by degeneration of dopaminergic cells. To describe the functional alterations specifically associated with this dopaminergic dysfunction, we have investigated the corticostriatal synaptic plasticity in mice overexpressing the human SOD1 (SOD1+) and the mutated (Gly(93)-->Ala) form (G93A+) of the same enzyme. We show that repetitive stimulation of the corticostriatal pathway generates long-term depression (LTD) in SOD1+ mice and in control (G93A-/SOD1-) animals, whereas in G93A+ mice the same stimulation generates an N-methyl-D-aspartic acid receptor-dependent long-term potentiation. No significant alterations were found in the intrinsic membrane properties of striatal medium spiny neurons and basal corticostriatal synaptic transmission of G93A+ mice. Bath perfusion of dopamine or the D(2) dopamine receptor agonist quinpirole restored LTD in G93A+ mice. Consistent with these in vitro results, habituation of locomotor activity and striatal-dependent active avoidance learning were impaired in G93A+ mice. Thus, degeneration of dopaminergic neurons in the substantia nigra of G93A+ mice causes substantial modifications in striatal synaptic plasticity and related behaviors, and may be a cellular substrate of the extrapyramidal motor and cognitive disorders observed in familial and sporadic ALS.     

The role of external ventricular drainage for the management of posterior cranial fossa tumours: a systematic review

Neurosurgical Review - Posterior cranial fossa tumours frequently develop hydrocephalus as first presentation in up to 80% of paediatric patients and 21.4% of adults, although it resolves after...     

Evaluation of acromegaly treatment direct costs with respect to biochemical control and follow-up length

Purpose

Acromegaly is a severe chronic endocrine disease. Achieving biochemical control often needs a multimodal treatment approach, including prolonged medical treatment. Aim of the study is to evaluate the burden of treatment direct costs with respect to the different therapeutic strategies, disease control, and follow-up length.

Methods

Single center retrospective study on 73 acromegaly patients. Costs of acromegaly treatments were computed based on a detailed revision of patients’ clinical charts.

Results

Median total treatment cost/patient was €47,343 during the entire follow-up (8 years), while median treatment cost/patient/year was €6811. The majority of patients received medical therapy (71/73, 97.3%). Median cost for first-line medical treatment (first-generation somatostatin receptor ligands) was lower compared to second-line treatments (pegvisomant monotherapy or combination therapies), considering both total (€22,824 vs €76,140; p?<?0.001), and yearly cost/patient (€4927 vs €9161; p?<?0.001). Sixty patients (82.2%) reached biochemical control at last follow-up (IGF-1?≤?1 xULN). The percentage of patients treated with first- or second-line medical therapies was comparable between controlled and uncontrolled patients (p?=?1.000), and the yearly cost/patient did not significantly differ between the two groups (€6936 vs €6680; p?=?0.829). Follow-up duration was significantly longer in controlled patients compared to the uncontrolled ones (8.7 vs 3.5 years; p?=?0.019).

Conclusions

Direct costs for the management of acromegaly have a significant burden on the healthcare systems. However, more than 80% of our patients reached biochemical control using multimodal approaches. Treatment modalities and yearly costs did not significantly differ between controlled and uncontrolled patients, while follow-up length represented a major determinant of biochemical outcome.

     

CD81-Receptor Associations — Impact for Hepatitis C Virus Entry and Antiviral Therapies

Tetraspanins are integral transmembrane proteins organized in microdomains displaying specific and direct interactions with other tetraspanins and molecular partners. Among them, CD81 has been implicated in a variety of physiological and pathological processes. CD81 also plays a crucial role in pathogen entry into host cells, including hepatitis C virus (HCV) entry into hepatocytes. HCV is a major cause of liver cirrhosis and hepatocellular carcinoma. HCV entry into hepatocytes is a complex process that requires the coordinated interaction of viral and host factors for the initiation of infection, including CD81, scavenger receptor BI, claudin-1, occludin, membrane-bound host cell kinases, Niemann-Pick C1 Like 1, Harvey rat sarcoma viral oncogene homolog (HRas), CD63 and transferrin receptor 1. Furthermore, recent data in HCV model systems have demonstrated that targeting critical components of tetraspanins and associated cell membrane proteins open new avenues to prevent and treat viral infection.     

Emphysematous urinoma as a complication of emphysematous pyelitis in a healthy adult male

The prevalence of endobronchial tuberculosis (EBTB) in patients with active tuberculosis is about 10% to 40%. The most common complication of EBTB is bronchial stenosis. Fistula formation by pulmonary tuberculosis is a very rare complication and is most commonly bronchopleural. The authors present a 53-year-old woman presented with chronic cough and abnormality in chest computed tomography scan. According to chest computed tomography scan finding, bronchoscopic study was done and bronchial lavage was obtained. Bronchial lavage was positive for acid fast bacilli. Bronchoscopy showed fistula formation between the right and left main bronchus, a rare manifestation of EBTB. The patient was treated with antituberculosis therapy, and her symptoms improved and radiological findings showed regression of pulmonary lesions.     

Inverse Correlation Between Vascular Calcification and Bone Mineral Density in Human Immunodeficiency Virus-Infected Patients

HIV-infected individuals suffer from accelerated aging, which manifests as premature cardiovascular and bone disease. However, little is known of the association of these two disorders in the HIV population. Our objective was to investigate the association between a marker of atherosclerosis (coronary artery calcium [CAC]) and low bone mineral density (BMD) in a cross-sectional cohort of HIV-infected patients. The study was conducted at the University of Modena and Reggio Emilia, Italy. A total of 636 consecutive middle-aged, HIV-infected subjects were recruited between January 2006 and December 2010. All patients underwent CAC and BMD assessment. Patients were categorized according to a CAC score <100 or >100 units based on previous literature that identified this cut-point as a marker of increased risk. Low femoral and lumbar spine BMD was defined as <25th percentile value for the study cohort. Logistic regression and bootstrap analysis were used to assess the independent association between CAC and BMD. The main outcome measure was a CAC score >100. Patients with CAC > 100 were older and more likely to be men, diabetic, and overweight. Patients with CAC < 100 had better renal function and a lower cardiovascular risk profile. After adjusting for age, sex, traditional and HIV-specific risk factors, vitamin D level, and PTH level, there was a significant association between CAC > 100 and low BMD for the femur (OR = 2.33, 95 % CI 1.09–4.99; p = 0.02) but not for the spine. Bootstrap analyses confirmed these findings. In summary, CAC was independently associated with low femoral BMD in HIV-infected patients. Future studies should test whether therapies that attenuate cardiovascular risk in HIV favorably impact bone health.     

Modulation of AMPA receptors in spinal motor neurons by the neuroprotective agent riluzole

We investigated the interaction of riluzole, a therapeutic agent used in amyotrophic lateral sclerosis (ALS), with alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) receptor channels in mouse spinal motor neurons in culture using whole-cell patch-clamp recording techniques. Kainate elicited concentration-dependent (EC(50) = 35 microM) inward currents in all the patched cells. These responses were mediated primarily through the activation of AMPA receptors with a negligible contribution from kainate receptors, because bath application of 100 microM GYKI53655, a potent noncompetitive AMPA receptor antagonist, completely blocked the kainate-induced currents. Riluzole (0.5-100 microM) reduced in a dose-dependent manner the kainate-induced currents with an IC(50) of 1.54 microM in all tested neurons (n = 25) and this effect was found to be reversible. The response to kainate decreased in the presence of 1 microM riluzole in all spinal motor neurons tested, without changing its EC(50), indicating a noncompetitive mechanism of inhibition. The amplitude of the responses induced by kainate under control condition and during riluzole was a linear function of the membrane potential. The reversal potential of the current was not significantly different in the two experimental conditions, whereas the total conductance of the motor neurons for the currents induced by 100 microM kainate was reduced significantly in the presence of 1 microM riluzole (P < 0.05). These results reveal an interaction of riluzole with glutamatergic neurotransmission in spinal cord motor neurons and can contribute to explain its beneficial effect in the ALS treatment.