Continuous monitoring of noise levels in the Gulf of Catania (Ionian Sea). Study of correlation with ship traffic

Acoustic noise levels were measured in the Gulf of Catania (Ionian Sea) from July 2012 to May 2013 by a low frequency (<1000Hz) hydrophone, installed on board the NEMO-SN1 multidisciplinary observatory. NEMO-SN1 is a cabled node of EMSO-ERIC, which was deployed at a water depth of 2100m, 25km off Catania. The study area is characterized by the proximity of mid-size harbors and shipping lanes. Measured noise levels were correlated with the passage of ships tracked with a dedicated AIS antenna. Noise power was measured in the frequency range between 10Hz and 1000Hz. Experimental data were compared with the results of a fast numerical model based on AIS data to evaluate the contribution of shipping noise in six consecutive 1/3 octave frequency bands, including the 1/3 octave frequency bands centered at 63Hz and 125Hz, indicated by the Marine Strategy Framework Directive (2008/56/EC).

Sensorineural Hearing Loss in a Patient Affected by Congenital Cytomegalovirus Infection: Is It Useful to Identify Comorbid Pathologies?

Sensorineural hearing loss (SNHL) is a common defect with a multifactorial etiology. Congenital cytomegalovirus infection (cCMV) is the most common infectious cause, and its early detection allows a prompt pharmacological treatment that can improve hearing prognosis. In a consistent percentage of profound SNHL, genetic causes and/or inner ear malformations are involved; their prompt diagnosis might change therapeutic options. This study reports a case of a 3- year-old female patient with symptomatic cCMV infection who also exhibits developmental delay, dysmorphic facial features, bilateral hearing loss, and cochlear incomplete partition, type 2, in 7q21.3 deletion. This deletion includes the genes DLX5 and DLX6 , which could be the candidate genes for the ear malformation named incomplete partition, type 2.

Novel mutations in KARS cause hypertrophic cardiomyopathy and combined mitochondrial respiratory chain defect

Mutations in KARS, which encodes for both mitochondrial and cytoplasmic lysyl-tRNA synthetase, have been so far associated with three different phenotypes: the recessive form of Charcot-Mary-Tooth polyneuropathy, the autosomal recessive nonsyndromic hearing loss and the last recently described condition related to congenital visual impairment and progressive microcephaly. Here we report the case of a 14-year-old girl with severe cardiomyopathy associated to mild psychomotor delay and mild myopathy; moreover, a diffuse reduction of cytochrome C oxidase (COX, complex IV) and a combined enzymatic defect of complex I (CI) and complex IV (CIV) was evident in muscle biopsy. Using the TruSight One sequencing panel we identified two novel mutations in KARS. Both mutations, never reported previously, occur in a highly conserved region of the catalytic domain and displayed a dramatic effect on KARS stability. Structural analysis confirmed the pathogenic role of the identified variants. Our findings confirm and emphasize that mt-aminoacyl-tRNA synthetases (mt-ARSs) enzymes are related to a broad clinical spectrum due to their multiple and still unknown functions.

Tuber Cinereum Hamartomas and Gelastic Epilepsy

We studied five patients with gelastic epilepsy sustained by hamartoma of the tuber cinereum, submitted to EEG and Video-EEG study and to MR examination. The mechanism of ictal laughter, clinical associations and prognosis for seizure control are discussed.

Hamartomas should be always suspected when gelastic seizures occur, and appropriate diagnostic tools should be employed for their diagnosis. In patients presenting with gelastic epilepsy, MR assessment of the hypothalamic region is necessary to identify a hamartoma of the tuber cinereum.

Moreover, the resolution of MR imaging provides a basis to correlate some of the clinical manifestations with the anatomical disposition of the lesion within the hypothalamus.

Gelastic epilepsy seems to correlate with large broad-based hamartomas in relationship with the mamillary bodies. In these cases, surgical treatment should be considered when symptoms are not sufficiently responsive to medical therapy.

Isolated macrocerebellum: description of six cases and literature review

BACKGROUND

Macrocerebellum is a rare entity described as an isolated and abnormal increase of the cerebellum (CB) size without morphological or signal abnormalities. There have been only eleven patients with macrocerebellum reported in the literature so far.

METHODS

From December 2011 to March 2014, among 950 paediatric patients that underwent a magnetic resonance scan of the brain in our department, in six subjects an abnormal increase of the cerebellar volume was suspected. A volumetric analysis was performed in all patients on T1- weighted 3D imaging to confirm the diagnosis of macrocerebellum. The ratios between (I) volume of the CB and volume of the supratentorial structures (STB) and (II) volume of the CB and the sum of CB and STB (WB) were calculated in order to normalize the absolute values obtained and compared with the normal values present in literature.

RESULTS AND DISCUSSION

Quantitative analysis confirmed an increased cerebellar volume relatively to the STB volume ("t": 6.9518; P<0.001) and to the WB ("t": 7.1415; P<0.001) volume in comparison to the normal controls available in literature. Clinical characteristics and other neuroradiological findings of the patients are described. We also describe the differential features between isolated macrocerebellum and other pathological conditions that are characterized by cerebellar enlargement such as Lhermitte-Duclos, Sotos syndrome, Costello syndrome, Williams syndrome, Alexander disease and fucosidosis. Furthermore a detailed literature review is provided. Macrocerebellum is always associated with an abnormal mental and motor development.

CONCLUSION

Macrocerebellum is a neuroradiological entity that can be identified qualitatively and confirmed quantitatively through volumetric analysis. This is the largest cohort of patients with macrocerebellum described so far. The data available in literature on this entity show that macrocerebellum is not a specific disease but an epiphenomenon found in heterogeneous brain disorders.

Can pontine trigeminal T2-hyperintensity suggest herpetic etiology of trigeminal neuralgia?

BACKGROUND

Trigeminal neuralgia (TN) is usually classified into two different categories: idiopathic and secondary. We have investigated the frequency of brainstem pontine lesions in patients with idiopathic TN without multiple sclerosis (MS) or stroke, and their association with herpes zoster (HZ) infection.

METHODS

Brain magnetic resonance imaging (MRI) studies of 28 patients with TN were retrospectively reviewed.

RESULTS

We found seven patients with clinical suspicion of HZ infection and pontine T2 hyperintense lesions, associated with nerve atrophy in one case. Fifteen patients had a neurovascular conflict (NVC) without brainstem involvement, two of them associated with trigeminal atrophy, while four patients had only volumetric reduction of the nerve. In all patients MRI findings were ipsilateral to the side of TN.

CONCLUSIONS

Pontine T2 hyperintensities could be considered as a MRI sign of TN in patients without NVCs. This "trigeminal pontine sign" (TPS) is frequently found in association with herpetic infections.

Akinetic crisis in dementia with Lewy bodies

BACKGROUND AND PURPOSE

Dementia with Lewy bodies (DLB) is characterised by neuroleptic hypersensitivity. It is unclear, however, whether the neuroleptic hypersensitivity implies an increased incidence of neuroleptic malignant syndrome (NMS) or of akinetic crisis (AC), which are expressions of the same possibly lethal clinical event, and whether AC in DLB can appear independently of neuroleptic treatment. In our prospective study, we assessed the incidence of AC in a cohort of DLB as compared with that in patients with Parkinson disease (PD).

METHODS

In total, 614 patients with PD and 236 DLB were recruited and followed during 2005-2013. AC was diagnosed as sudden akinetic state unresponsive to dopaminergic rescue drugs, dysphagia and serological alterations without recovery for 48 h or more requiring hospital admission. Exposure to neuroleptics was specifically evaluated, because of the high implicit risk in DLB.

RESULTS

24 patients with PD (3.9%) and 16 patients with DLB (6.8%) developed AC. 77 (32.6%) DLB and 32 (5.2%) PD were exposed to typical neuroleptics, but only 8 DLB and 3 PD presented with AC. Disease duration before AC was lower in DLB than in PD group (p<0.01). Outcome was fatal in 8 patients with (50%) DLB and 3 (12.5%) PD (p=0.05). When age and use of neuroleptics were adjusted for into a Cox proportional hazards model predicting time to AC, the HR of patients with DLB was 13.0 (95% CI 4.23 to 39.9; p<0.001).

CONCLUSIONS

AC in DLB can appear independently of neuroleptic treatment, occurs earlier and is more frequently fatal than in PD.

Autophagy regulates satellite cell ability to regenerate normal and dystrophic muscles

Autophagy is emerging as a key regulatory process during skeletal muscle development, regeneration and homeostasis, and deregulated autophagy has been implicated in muscular disorders and age-related muscle decline. We have monitored autophagy in muscles of mdx mice and human Duchenne muscular dystrophy (DMD) patients at different stages of disease. Our data show that autophagy is activated during the early, compensatory regenerative stages of DMD. A progressive reduction was observed during mdx disease progression, in coincidence with the functional exhaustion of satellite cell-mediated regeneration and accumulation of fibrosis. Moreover, pharmacological manipulation of autophagy can influence disease progression in mdx mice. Of note, studies performed in regenerating muscles of wild-type mice revealed an essential role of autophagy in the activation of satellite cells upon muscle injury. These results support the notion that regeneration-associated autophagy contributes to the early compensatory stage of DMD progression, and interventions that extend activation of autophagy might be beneficial in the treatment of DMD. Thus, autophagy could be a 'disease modifier' targeted by interventions aimed to promote regeneration and delay disease progression in DMD.

MYH7-related myopathies: clinical, histopathological and imaging findings in a cohort of Italian patients

BACKGROUND

Myosin heavy chain 7 (MYH7)-related myopathies are emerging as an important group of muscle diseases of childhood and adulthood, with variable clinical and histopathological expression depending on the type and location of the mutation. Mutations in the head and neck domains are a well-established cause of hypertrophic cardiomyopathy whereas mutation in the distal regions have been associated with a range of skeletal myopathies with or without cardiac involvement, including Laing distal myopathy and Myosin storage myopathy. Recently the spectrum of clinical phenotypes associated with mutations in MYH7 has increased, blurring this scheme and adding further phenotypes to the list. A broader disease spectrum could lead to misdiagnosis of different congenital myopathies, neurogenic atrophy and other neuromuscular conditions.

RESULTS

As a result of a multicenter Italian study we collected clinical, histopathological and imaging data from a population of 21 cases from 15 families, carrying reported or novel mutations in MYH7. Patients displayed a variable phenotype including atypical pictures, as dropped head and bent spine, which cannot be classified in previously described groups. Half of the patients showed congenital or early infantile weakness with predominant distal weakness. Conversely, patients with later onset present prevalent proximal weakness. Seven patients were also affected by cardiomyopathy mostly in the form of non-compacted left ventricle. Muscle biopsy was consistent with minicores myopathy in numerous cases. Muscle MRI was meaningful in delineating a shared pattern of selective involvement of tibialis anterior muscles, with relative sparing of quadriceps.

CONCLUSION

This work adds to the genotype-phenotype correlation of MYH7-relatedmyopathies confirming the complexity of the disorder.

Cerebral Accidents in Pediatric Diabetic Ketoacidosis: Different Complications and Different Evolutions

Diabetic ketoacidosis (DKA) may be associated with neurologic complications: the most common is cerebral edema while the risk of venous and arterial stroke is rare. There is a pathogenetic link between DKA, hypercoagulability and stroke, whose risk is underestimated by clinicians. Our cases present a wide spectrum of cerebral accidents during DKA, the first one being diffuse cerebral edema, the second one venous stroke after 5 days of DKA resolution, while the third one multifocal edema suspected to be extrapontine myelinolysis although without electrolyte imbalance. Our cases suggest that DKA requires very accurate treatment, particularly at an early age, and it can be complicated by cerebral accidents even with appropriate medical care.

De novo PIK3R2 variant causes polymicrogyria, corpus callosum hyperplasia and focal cortical dysplasia

We report an 8-year-old boy with a complex cerebral malformation, intellectual disability, and complex partial seizures. Whole-exome sequencing revealed a yet unreported de novo variant in the PIK3R2 gene that was recently associated with megalencephaly-polymicrogyria-polydactyly-hydrocephalus (MPPH) syndrome and bilateral perisylvian polymicrogyria (BPP). Our patient showed cerebral abnormalities (megalencephaly, perisylvian polymicrogyria, and mega corpus callosum) that were consistent with these conditions. Imaging also showed right temporal anomalies suggestive of cortical dysplasia. Until now, only three variants (c.1117G>A (p.(G373R)), c.1126A>G (p.(K376E)) and c.1202T>C (p.(L401P))) affecting the SH2 domain of the PIK3R2 protein have been reported in MPPH and BPP syndromes. In contrast to the variants reported so far, the patient described herein exhibits the c.1669G>C (p.(D557H)) variant that affects a highly conserved residue at the interface with the PI3K catalytic subunit α. The phenotypic spectrum associated with variants in this gene and its pathway are likely to continue to expand as more cases are identified.