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Textile organic electrochemical transistors (txOECTs) are a new class of wearable biosensors used to monitor physiological parameters in bio fluids of clinical interest. Herein the selectivity of a textile biosensor was improved directly functionalizing the textile device with ion selective membranes. The device was prepared by a series of consecutive functionalization of the textile fiber, first by applying the conductive polymer poly (3,4-ethylenedioxythiophene):poly (styrene sulfonate) (PEDOT:PSS) and subsequently the ion selective membrane based on different ionophores with the aim of measuring electrolytes in sweat. The ion selective membranes were previously tested and optimized by potentiometric measurements. The biosensor devices were studied with different concentration of electrolytes. Membrane selectivity was tested comparing transistor response with interfering ions, proving successfully the selective response to sodium, potassium and calcium ions. The ability of the textile biosensors to discriminate among the cations was demonstrated over the 10−5 - 1 M concentration range, a concentration range found in sweat. The electronic parameters of the txOECTs show differences not only in modulation response but also in time constants of kinetic behavior. The selective determination of potassium and calcium in sweat has a great importance in different applications, for example, in human sweat monitoring, to understand physiological conditions, like dehydration, cardiac bioactivity and hypokalemia.

Aims Pompe disease is an autosomal recessive lysosomal storage disorder resulting from deficiency of acid α-glucosidase (GAA) enzyme. Histopathological hallmarks in skeletal muscle tissue are fiber vacuolization and autophagy. Since 2006, ERT is the only approved treatment with human recombinant GAA alglucosidase alfa. We designed a study to examine ERT-related skeletal muscle changes in 18 modestly to moderately affected LOPD patients along with the relationship between morphological/biochemical changes and clinical outcomes. Treatment duration was short-to-long term. Methods We examined muscle biopsies from 18 LOPD patients at both histopathological and biochemical level. All patients underwent two muscle biopsies, before and after ERT administration respectively. The study is partially retrospective because the first biopsies were taken before the study was designed whereas the second biopsy was always performed after at least six months of ERT administration. Results After ERT, 15 out of 18 patients showed improved 6MWT (p=0.0007) and most of them achieved respiratory stabilization. Pre-treatment muscle biopsies disclosed marked histopathological variability, ranging from an almost normal pattern to a severe vacuolar myopathy. After treatment, we detected morphological improvement in 15 patients and worsening in 3 patients. Post-ERT GAA enzymatic activity was mildly increased compared with pre-treatment levels in all patients. Protein levels of the mature enzyme increased in 14 of the 18 patients (mean increase = +35%; p

Spinocerebellar ataxias (SCAs) are a genetically heterogeneous group of cerebellar degenerative disorders, characterized by progressive gait unsteadiness, hand incoordination, and dysarthria. Ataxia type 1 (SCA1) is caused by the expansion of a CAG trinucleotide repeat in the SCA1 gene resulting in the atypical extension of a polyglutamine (polyQ) tract within the ataxin-1 protein. Our main objective was to investigate the mitochondrial oxidative metabolism in the cerebellum of transgenic SCA1 mice. SCA1 transgenic mice develop clinical features in the early life stages (around 5 weeks of age) presenting pathological cerebellar signs with concomitant progressive Purkinje neuron atrophy and relatively little cell loss; this evidence suggests that the SCA1 phenotype is not the result of cell death per se, but a possible effect of cellular dysfunction that occurs before neuronal demise. We studied the mitochondrial oxidative metabolism in cerebellar cells from both homozygous and heterozygous transgenic SCA1 mice, aged 2 and 6 months. Histochemical examination showed a cytochrome-c-oxidase (COX) deficiency in the Purkinje cells (PCs) of both heterozygous and homozygous mice, the oxidative defect being more prominent in older mice, in which the percentage of COX-deficient PC was up to 30%. Using a laser-microdissector, we evaluated the mitochondrial DNA (mtDNA) content on selectively isolated COX-competent and COX-deficient PC by quantitative Polymerase Chain Reaction and we found mtDNA depletion in those with oxidative dysfunction. In conclusion, the selective oxidative metabolism defect observed in neuronal PC expressing mutant ataxin occurs as early as 8 weeks of age thus representing an early step in the PC degeneration process in SCA1 disease.

The important depletion of mitochondrial DNA (mtDNA) and the general depression of mitochondrial respiratory chain complex levels (including complex II) have been confirmed, implying an increasing paucity of mitochondria in the muscle from patients with types I, II, and III spinal muscular atrophy (SMA-I, -II, and -III, respectively).To investigate mitochondrial dysfunction in a large series of muscle biopsy samples from patients with SMA.We studied quadriceps muscle samples from 24 patients with genetically documented SMA and paraspinal muscle samples from 3 patients with SMA-II undergoing surgery for scoliosis correction. Postmortem muscle samples were obtained from 1 additional patient. Age-matched controls consisted of muscle biopsy specimens from healthy children aged 1 to 3 years who had undergone analysis for suspected myopathy. Analyses were performed at the Neuromuscular Unit, Istituto di Ricovero e Cura a Carattere Scientifico Foundation Ca' Granda Ospedale Maggiore Policlinico-Milano, from April 2011 through January 2015.We used histochemical, biochemical, and molecular techniques to examine the muscle samples.Respiratory chain activity and mitochondrial content.Results of histochemical analysis revealed that cytochrome-c oxidase (COX) deficiency was more evident in muscle samples from patients with SMA-I and SMA-II. Residual activities for complexes I, II, and IV in muscles from patients with SMA-I were 41%, 27%, and 30%, respectively, compared with control samples (P .005). Muscle mtDNA content and cytrate synthase activity were also reduced in all 3 SMA types (P .05). We linked these alterations to downregulation of peroxisome proliferator-activated receptor coactivator 1α, the transcriptional activators nuclear respiratory factor 1 and nuclear respiratory factor 2, mitochondrial transcription factor A, and their downstream targets, implying depression of the entire mitochondrial biogenesis. Results of Western blot analysis confirmed the reduced levels of the respiratory chain subunits that included mitochondrially encoded COX1 (47.5%; P = .004), COX2 (32.4%; P .001), COX4 (26.6%; P .001), and succinate dehydrogenase complex subunit A (65.8%; P = .03) as well as the structural outer membrane mitochondrial porin (33.1%; P .001). Conversely, the levels of expression of 3 myogenic regulatory factors-muscle-specific myogenic factor 5, myoblast determination 1, and myogenin-were higher in muscles from patients with SMA compared with muscles from age-matched controls (P .05).Our results strongly support the conclusion that an altered regulation of myogenesis and a downregulated mitochondrial biogenesis contribute to pathologic change in the muscle of patients with SMA. Therapeutic strategies should aim at counteracting these changes.