Quantitative, functional MRI and neurophysiological markers in a case of Gerstmann-Sträussler-Scheinker syndrome.

Gerstmann-Sträussler-Scheinker syndrome (GSS) is an inherited autosomal dominant prion disease, caused by a codon 102 proline to leucine substitution (P102L) in the prion protein gene (PRNP). We describe the case of a 40-year-old male, affected by a slowly progressive gait disturbance, leg weakness and cognitive impairment. Genomic DNA revealed a point mutation of PRNP at codon 102, resulting in P102L, and the diagnosis of GSS was confirmed. Somatosensory evoked potentials showed alterations of principal parameters, particularly in the right upper and lower limbs. Laser-evoked potentials were indicative of nociceptive system impairment, especially in the right upper and lower limbs. Conventional magnetic resonance imaging (MRI) revealed marked atrophy of the vermis and cerebellar hemispheres and mild atrophy of the middle cerebellar peduncles and brainstem, as confirmed by a brain volume automatic analysis. Resting-state functional MRI showed increased functional connectivity in the bilateral visual cortex, and decreased functional connectivity in the bilateral frontal pole and supramarginal and precentral gyrus. Albeit limited to a single case, this is the first study to assess structural and functional connectivity in GSS using a multimodal approach.

Altered Erythropoiesis in Mouse Models of Type 3 Hemochromatosis.

Type 3 haemochromatosis (HFE3) is a rare genetic iron overload disease which ultimately lead to compromised organs functioning. HFE3 is caused by mutations in transferrin receptor 2 (TFR2) gene that codes for two main isoforms (Tfr2α and Tfr2ß). Tfr2α is one of the hepatic regulators of iron inhibitor hepcidin. Tfr2ß is an intracellular isoform of the protein involved in the regulation of iron levels in reticuloendothelial cells. It has been recently demonstrated that Tfr2 is also involved in erythropoiesis. This study aims to further investigate Tfr2 erythropoietic role by evaluating the erythropoiesis of two Tfr2 murine models wherein either one or both of Tfr2 isoforms have been selectively silenced (Tfr2 KI and Tfr2 KO). The evaluations were performed in bone marrow and spleen, in 14 days' and 10 weeks' old mice, to assess erythropoiesis in young versus adult animals. The lack of Tfr2α leads to macrocytosis with low reticulocyte number and increased hemoglobin values, together with an anticipation of adult BM erythropoiesis and an increased splenic erythropoiesis. On the other hand, lack of Tfr2ß (Tfr2 KI mice) causes an increased and immature splenic erythropoiesis. Taken together, these data confirm the role of Tfr2α in modulation of erythropoiesis and of Tfr2ß in favoring iron availability for erythropoiesis.

Oral administration of moxidectin for treatment of murine acariosis due to Radfordia affinis.

A field trial was conducted to assess the safety and efficacy of oral administration of moxidectin in mice naturally infected with the fur mites Radfordia affinis. The natural infection was diagnosed in two colonies within a large academic institution by direct hair examination. Animals received moxidectin (1% Cydectin, FortDodge) at an oral dosage of approximately 2 mg/kg body weight by micropipette; administration was repeated after 15 days. Forty mice served as an untreated control group. Moxidectin treatment resulted in clinical improvement within a few days after initial treatment, and mites were eradicated from all infested animals at day 30. No side effects or signs of ill health were observed in any of the treated animals. To our knowledge, this is the first report of oral moxidectin for treatment of murine acariosis.

Measurement of faecal corticoid metabolites in domestic dogs.

In the present study we established a method for the determination of faecal glucocorticoid metabolites in dogs and then used the assay to evaluate the adrenocortical activity in 12 dogs divided into two groups. In group A faecal samples were collected at their domestic setting. In group B, faecal samples were collected at home prior to transport to a boarding kennel, where faecal samples were then collected. In faecal samples most of the steroids were extracted with methanol and determined using a radioimmunoassay with an anti-cortisol antibody. Dogs in group A did not show any statistically significant inter-day variations in the basal levels of faecal corticoid metabolites. Faecal corticoid metabolites in dogs in group B were significantly higher on the first day at the kennel compared to animals kept at home. The peak concentration was found after 24 hours and followed by a slow decline. These results suggest that extraction with methanol and dosage with an anti-cortisol antibody by radioimmunoassay represents a valid approach technique for determination of faecal glucocorticoid metabolites and accurately reflects adrenocortical activity.

MR-imaging of post-traumatic olivary hypertrophy.

We present clinical and magnetic resonance (MR) findings in 83 patients with inner cerebral trauma (ICT). In addition to the ICT-related lesions, uni- or bilateral enlargement and signal abnormalities of the inferior olivary nucleus were detected by MR in 9.6% of patients as a consequence of lesions within the dentato-rubro-olivary pathway. Clinically, segmental myoclonias were present in five patients. These observations suggest that MR imaging is highly sensitive in the detection of olivary hypertrophy and of causative traumatic lesions of the dentato-rubro-olivary pathway.