Functional characterization of muscle fibres from patients with chronic fatigue syndrome: case-control study.

Chronic fatigue syndrome (CFS) is a disabling condition characterized by unexplained chronic fatigue that impairs normal activities. Although immunological and psychological aspects are present, symptoms related to skeletal muscles, such as muscle soreness, fatigability and increased lactate accumulation, are prominent in CFS patients. In this case-control study, the phenotype of the same biopsy samples was analyzed by determining i) fibre-type proportion using myosin isoforms as fibre type molecular marker and gel electrophoresis as a tool to separate and quantify myosin isoforms, and ii) contractile properties of manually dissected, chemically made permeable and calcium-activated single muscle fibres. The results showed that fibre-type proportion was significantly altered in CSF samples, which showed a shift from the slow- to the fast-twitch phenotype. Cross sectional area, force, maximum shortening velocity and calcium sensitivity were not significantly changed in single muscle fibres from CSF samples. Thus, the contractile properties of muscle fibres were preserved but their proportion was changed, with an increase in the more fatigue-prone, energetically expensive fast fibre type. Taken together, these results support the view that muscle tissue is directly involved in the pathogenesis of CSF and it might contribute to the early onset of fatigue typical of the skeletal muscles of CFS patients.

Age-dependent effects on functional aspects in human satellite cells.

In humans aging is a complex process that determines many physical and metabolic alterations correlated to the accumulation of oxidative damage in different tissues. Sarcopenia is an age-related nonpathological condition that includes a progressive loss of mass and strength in skeletal muscle, associated with a decline in the fibers' functional capability. This condition could be correlated to abnormal reactive oxygen species (ROS) accumulation with consequent fiber oxidative damage. This complex situation is not only evident in mature muscle fibers but also in muscle resident satellite cells (involved in fiber damage repairing) in which some functional parameters, at least for that concerns the Ca(2+) homeostasis, seem to be modified. In fact, our data show that there is an age-dependent increase of lipid peroxidation, in cultured myotubes (differentiated and fused satellite cells) after 7 days of in vitro differentiation. In these substrates also the capacity of these cells to produce Ca(2+) transient in response to various stimuli (ATP, caffeine, nicotine, KCl) is, sometimes, drastically modified. In particular, the presence of an age-dependent defective status of excitation-contraction (EC) coupling apparatus is supported by a single cell Ca(2+) analysis obtained from myotubes (derived from aged muscles) in the presence of 40 mM caffeine or 40 mM KCl. The alkaloid presence induces a complete emptying of ryanodine-dependent calcium stores indicating a probable integrity both of SR-terminal cisternae and/or the specific Ca(2+) channel known as RyR1. However, if a sarcolemmal depolarization is induced by the addition of 40 mM KCl in the experimental medium then Ca(2+) release RyR1-dependent can be observed only if Ca(2+) is present in the experimental solution. These results suggest that the EC uncoupling status could be due to the alteration of the interaction between RyR and DHPR. The two receptors are present and functionally active in myotubes from aged donors but they are probably still not in the right localization. These results suggest that during donor's life the satellite cells undergo an aging process similar to the one observed in skeletal muscle tissue, even if they are in a quiescence status for most of the time.

Neonatal eating epilepsy: pathophysiological and pharmacologic aspects.

We report a case of neonatal Eating Epilepsy. The baby was admitted to the Neonatal Intensive Care Unit of Chieti after delivery, with respiratory distress syndrome. In the first day of life the baby had an episode of arterial desaturation and cyanosis with EEG alterations. After laboratory and instrumental investigations we found a correlation between EEG abnormalities and GER. So we administered a combination of anticonvulsive and antacid therapy and, considering the total improvement of EEG, we diagnosed a neonatal form of "eating epilepsy".

Culture of human skeletal muscle myoblasts: timing appearance and localization of dystrophin-glycoprotein complex and vinculin-talin-integrin complex.

The dystrophin-glycoprotein complex together with the vinculin-talin-integrin complex plays an important role in muscle function; in fact the mutations of their elements lead to diverse forms of muscular dystrophies. The relationship between the elements of dystrophin-glycoprotein complex and vinculin-talin-integrin and the time course of their formation are still not known in detail. In order to better understand this relationship we studied their expression during development in normal human skeletal muscle culture. Using a standardized muscle cell culture procedure, this study was performed to analyze the timing, appearance and the localization of some proteins of the dystrophin-glycoprotein complex and vinculin-talin-integrin complex during cellular proliferation (myoblast) and differentiation (4, 7, 15 and 21 days). The indirect immunofluorescence technique was used and cells were examined using a Meta Zeiss LSM510 confocal laser scanning inverted microscope. We examined the progressive appearance of the following proteins: alpha, beta, gamma, delta-sarcoglycans, beta-dystroglycan, dystrophin, talin, vinculin and integrin isoform alpha7/beta1. Immunofluorescence of these proteins, in satellite cells entering myogenic differentiation, revealed different patterns of localization depending on the time of culture. We showed that nondifferentiated cultures of human myoblasts expressed a perinuclear distribution of all proteins tested. During myoblast differentiation into myotubes (4 days) immunofluorescence gradually increased and was located in the whole cytoplasm. Subsequently, at day 7, a strong and homogeneous cytoplasmic labelling of all proteins was seen. At 15 days the distribution of the proteins was on the membrane. At this time some myotubes displayed a significant degree of precostameric banding pattern. As fusion proceeded at 21 days, the cytodistribution progressively changed and appeared along fibrillar longitudinal structures, and myotubes showed a clear periodic distribution (costameres). In conclusion, in normal human muscle cultures DGC and vinculin-talin-integrin proteins are first localized in the perinuclear region, then they diffuse in the cytoplasm and finally form at the plasma membrane into typical rib-like structures that are sarcolemma-associated.

A case of Smith-Lemli-Opitz Syndrome, defect of cholesterol biosynthesis.

We report the case of a child with Smith-Lemli-Opitz Syndrome. The pregnancy was complicated by prenatal growth retardation. The baby was admitted to the Neonatal Intensive Care Unit of Chieti when she was five months old. She showed postnatal growth retardation, trouble sucking and swallowing, microcephaly and multiple major and minor malformations, including characteristic facial features and 2-3 syndactyly of the toes. We found correlations between multiple congenital malformations, failure to thrive and low plasmatic cholesterol measurement.

Excessively high magnetic resonance signal in preterm infants and neuropsychobehavioural follow-up at 2 years.

The diffuse excessive high-signal intensity (DEHSI) findings in the T2 weighted scans of white matter (WM), besides the corresponding low signal in the T1 weighted images, are usually more evident around the periventricular regions. It is not clear whether the DEHSI should be considered as a diffuse WM injury rather than a sign of delayed maturation of the WM. Eighty nine preterm infants at the full-term equivalent age (FEA) were studied using conventional Magnetic Resonance (MR) imaging of the brain. Based on the MR findings, the infants studied were divided into three groups: the control group presenting normal WM, the DEHSI group and the group with other WM lesions. Ten newborns were not included in the statistical analysis because they presented evidence of precedent germinal matrix hemorrhage (GMH-IVH) which cannot be considered as WM lesions. Seventy nine infants were enrolled in a program of neuropsychobehavioural study follow-up until 24 months of age. Each infant was evaluated for those variables which mostly affect the occurrence of neuropsychomotor disability. In the DEHSI infant group, significantly lower mean pH and mean base excess (BE) values were found in comparison to controls, while the mean birth weight (BW) was significantly higher. No significant difference was observed between the mean 1st minute Apgar Score, mean birth gestational age (GA) and assisted ventilation mean duration of controls and DEHSI groups. Finally, no significant difference between the parameters studied was found by comparing the WM lesion infants group to the DEHSI infants one. Our observations, together with follow-up studies, even up to school age, confirm that DEHSI has a clinical significance and cannot be considered as a simple indicator of delayed WM maturation.

Glutaric aciduria type II: a case report.

We report a case of a newborn with Glutaric aciduria type II. Pregnancy was complicated by polyhidramnios and fetal bradycardia. Cardiomegaly was detected by fetal echocardiography. The baby was admitted to the Neonatal Intensive Care Unit of Chieti with respiratory distress syndrome immediately after delivery. He showed head and neck edema, micrognathia, paucity of movement, pronounced hypotonia, bilateral cryptorchidism, micropenis, small hands, skin hyperelasticity and joint hypermobility. Serum and urine analysis showed a fatty acid beta-oxidation disorder. He died at 7 days of age for cardiac arrest and autopsy showed marked hepatic and cardiac vacuolisation, lipid storage myopathy and glial cells vacuolisation. Based upon these findings, we speculate that this infant may be suffering from inborn metabolic disease.