Fragile X mental retardation protein (FMRP) and metabotropic glutamate receptor subtype 5 (mGlu5) control stress granule formation in astrocytes.

Fragile X syndrome (FXS) is a common form of intellectual disability and autism caused by the lack of Fragile X Mental Retardation Protein (FMRP), an RNA-binding protein involved in RNA transport and protein synthesis. Upon cellular stress, global protein synthesis is blocked and mRNAs are recruited into stress granules (SGs), together with RNA-binding proteins including FMRP. Activation of group-I metabotropic glutamate (mGlu) receptors stimulates FMRP-mediated mRNA transport and protein synthesis, but their role in SGs formation is unexplored. To this aim, we pre-treated wild type (WT) and Fmr1 knockout (KO) cultured astrocytes with the group-I-mGlu receptor agonist (S)-3,5-Dihydroxyphenylglycine (DHPG) and exposed them to sodium arsenite (NaAsO2), a widely used inducer of SGs formation. In WT cultures the activation of group-I mGlu receptors reduced SGs formation and recruitment of FMRP into SGs, and also attenuated phosphorylation of eIF2α, a key event crucially involved in SGs formation and inhibition of protein synthesis. In contrast, Fmr1 KO astrocytes, which exhibited a lower number of SGs than WT astrocytes, did not respond to agonist stimulation. Interestingly, the mGlu5 receptor negative allosteric modulator (NAM) 2-methyl-6-(phenylethynyl)pyridine (MPEP) antagonized DHPG-mediated SGs reduction in WT and reversed SGs formation in Fmr1 KO cultures. Our findings reveal a novel function of mGlu5 receptor as modulator of SGs formation and open new perspectives for understanding cellular response to stress in FXS pathophysiology.

SERUM YKL-40 IN CHILDREN WITH ASTHMA.

Asthma is one of the most common chronic diseases in children. To date the diagnosis of asthma is mainly clinical, based on the clinical history, a careful physical examination and lung function tests. However, symptoms are often not specific and lung function tests are not very sensitive. In order to find a solution to this problem new biomarkers of airway inflammation are being developed. YKL-40 is a chitinase-like protein that has a role in the inflammation and tissue remodeling in several human diseases. The aim of this study is to evaluate serum levels of YKL40 in children with intermittent or persistent asthma. We performed a cross-sectional analysis of serum samples from a cohort of patients with asthma and healthy controls. Patients with asthma were stratified according to four levels of asthma severity (mild intermittent, mild persistent, moderate persistent, and severe persistent). The analysis of serum samples was performed with the use of a commercially available enzyme-linked immune-adsorbent assay (ELISA) kit (Quidel). The minimum detection limit of the assay for YKL-40 is 15.6 ng per milliliter (ng/ml). Our data showed that circulating YKL-40 levels are significantly higher in patients with asthma than healthy subjects (36±18.6 vs 14:41±2.88, p= 0.001). Furthermore, we found significantly higher values of YKL-40 in both groups of children with intermittent asthma (p less than 0.001) and persistent asthma (p less than 0.001) than healthy controls. However, no correlation was found with duration and severity of asthmatic disease (r = 0:18, p= 0:33, r = 0.28 P = 0:13, respectively). Our data allow us to suggest that YKL-40 represents a useful biomarker of asthma in children with intermittent or persistent asthma.

SERUM AND BAL YKL-40 LEVELS IN DIFFERENT INFLAMMATORY LUNG DISEASES: AN UPDATE.

YKL-40 (also called chitinase 3-like-1 or human cartilage glycoprotein 39) is a chitinase-like protein belonging to the family 18 of glycosyl hydrolase (GH18). This protein is involved in the inflammatory process acting as pro-inflammatory cytokine secreted by neutrophils, activated human macrophages, vascular smooth muscle cells and cancer cells. It has been shown that YKL-40 has a role in pathological tissue remodeling and development of fibrosis of several diseases. To date, the biological and pathophysiological function of YKL-40 protein in pulmonary diseases is still unclear. This review focuses on the role of YKL-40 in diagnosis and monitoring of different lung diseases in order to assess whether this protein could be used as biomarker of specific conditions featured by inflammation and fibrosis. A comprehensive review of the literature using PubMed database, with appropriate terms, was undertaken for articles in English published since 1997. The literature search was undertaken in October 2014.

Assessment of pulmonary function in a follow-up of premature infants: our experience.

Respiratory diseases are a major cause of morbidity in neonates, especially preterm infants; a long term complication of prematurity such as bronchopulmonary dysplasia (BPD) is particularly relevant today. The exact role of the Pulmonary Function Test (PFT) in this area is not yet well defined; the PFT in newborns and infants - in contrast to what happens in uncooperative children and adults - are routinely used only in a few centers. The assessment of pulmonary function in newborns and infants, however, is nowadays possible with the same reliability that in cooperative patients with the possibility to extend the assessment of polmonary function from bench to bed. The assessment of pulmonary function must be carried out with non invasive and safe methods, at the bedside, with the possibility of continuous monitoring and providing adequate calculation and management of data. The ability to assess lung function helps to define the mechanisms of respiratory failure, improving the treatment and its effects and is therefore a useful tool in the follow-up of newborn and infant with pulmonary disease.

Comparison between two different modes of non-invasive ventilatory support in preterm newborn infants with respiratory distress syndrome mild to moderate: preliminary data.

Despite of improved survival of premature infants, the incidence of long term pulmonary complications, mostly associated with ventilation-induced lung injury, remains high. Non invasive ventilation (NIV) is able to reduce the adverse effects of mechanical ventilation. Although nasal continuous positive airway pressure (NCPAP) is an effective mode of NIV, traumatic nasal complications and intolerance of the nasal interface are common. Recently high flow nasal cannula (HFNC) is emerging as a better tolerated form of NIV, allowing better access to the baby's face, which may improve nursing, feeding and bonding. HFNC may be effective in the treatment of some neonatal respiratory conditions while being more user-friendly for care-givers than conventional NCPAP. Limited evidence is available to support the specific role, efficacy and safety of HFNC in newborns and to demonstrate efficacy compared with NCPAP; some studies suggest a potential role for HFNC in respiratory care of the neonate as a distinct non invasive ventilatory support. We present the preliminary data of a randomized clinical trial; the aim of this study was to assess efficacy and safety of HFNC compared to NCPAP in preterm newborns with mild to moderate respiratory distress syndrome (RDS).

[Therapy with high-flow nasal prongs in preterm infants]. / La terapia con nasocannule ad alto flusso nel neonato pretermine.

Despite of improved survival of premature infants, the incidence of long-term pulmonary complications, mostly associated with ventilation-induced lung injury, remains high. Non invasive ventilation (NIV) is able to reduce the adverse effects of mechanical ventilation. Although nasal continuous positive airway pressure (NCPAP) is an effective mode of NIV, traumatic nasal complications and intolerance of the nasal interface are common. Recently high flow nasal cannula (HFNC) is emerging as an efficient, better tolerated form of NIV, allowing better access to the baby's face, which may improve nursing, feeding and bonding. The aim of this review is to discuss the available evidence of effectiveness and safety of HFNC in preterm newborns with respiratory distress syndrome (RDS). It is known that distending pressure generated by HFNC increases with increasing flow rate and decreasing infant size and varies according to the amount of leaks by nose and mouth. The effects of HFNC on lung mechanics, its clinical efficacy and safety are still insufficiently investigated. In conclusion, there is a growing evidence of the feasibility of HFNC as an alternative mode of NIV. However, further larger randomized trials are required, before being able to recommend HFNC in the treatment of moderate respiratory distress of preterm infants.

[Assessment of pulmonary function in a follow-up of premature infants: our experience]. / Valutazione della funzionalità respiratoria nell'ambito di un follow up respiratorio di neonati prematuri: la nostra esperienza.

Respiratory diseases are a major cause of morbidity in neonates, especially preterm infants; a long-term complication of prematurity such as bronchopulmonary dysplasia (BPD) is particularly relevant today. The exact role of the Pulmonary Function Test (PFT) in this area is not yet well defined; the PFT in newborns and infants--in contrast to what happens in uncooperative children and adults--are routinely used only in a few centers. The assessment of pulmonary function in newborns and infants, however, is nowadays possible with the same reliability that in cooperative patients with the possibility to extend the assessment of polmonary function from bench to bed. The assessment of pulmonary function must be carried out with non invasive and safe methods, at the bedside, with the possibility of continuous monitoring and providing adequate calculation and management of data. The ability to assess lung function helps to define the mechanisms of respiratory failure, improving the treatment and its effects and is therefore a useful tool in the follow-up of newborn and infant with pulmonary disease.

5-HT(1A) and 5-HT(7) receptors differently modulate AMPA receptor-mediated hippocampal synaptic transmission.

We have studied the effects of 5-HT(1A) and 5-HT(7) serotonin receptor activation in hippocampal CA3-CA1 synaptic transmission using patch clamp on mouse brain slices. Application of either 5-HT or 8-OH DPAT, a mixed 5-HT(1A)/5-HT(7) receptor agonist, inhibited AMPA receptor-mediated excitatory post synaptic currents (EPSCs); this effect was mimicked by the 5-HT(1A) receptor agonist 8-OH PIPAT and blocked by the 5-HT(1A) antagonist NAN-190. 8-OH DPAT increased paired-pulse facilitation and reduced the frequency of mEPSCs, indicating a presynaptic reduction of glutamate release probability. In another group of neurons, 8-OH DPAT enhanced EPSC amplitude but did not alter paired-pulse facilitation, suggesting a postsynaptic action; this effect persisted in the presence of NAN-190 and was blocked by the 5-HT(7) receptor antagonist SB-269970. To confirm that EPSC enhancement was mediated by 5-HT(7) receptors, we used the compound LP-44, which is considered a selective 5-HT(7) agonist. However, LP-44 reduced EPSC amplitude in most cells and instead increased EPSC amplitude in a subset of neurons, similarly to 8-OH DPAT. These effects were respectively antagonized by NAN-190 and by SB-269970, indicating that under our experimental condition LP-44 behaved as a mixed agonist. 8-OH DPAT also modulated the current evoked by exogenously applied AMPA, inducing either a reduction or an increase of amplitude in distinct neurons; these effects were respectively blocked by 5-HT(1A) and 5-HT(7) receptor antagonists, indicating that both receptors exert a postsynaptic action. Our results show that 5-HT(1A) receptors inhibit CA3-CA1 synaptic transmission acting both pre- and postsynaptically, whereas 5-HT(7) receptors enhance CA3-CA1 synaptic transmission acting exclusively at a postsynaptic site. We suggest that a selective pharmacological targeting of either subtype may be envisaged in pathological loss of hippocampal-dependent cognitive functions. In this respect, we underline the need for new selective agonists of 5-HT(7) receptors.

Posterior fossa abnormalities in hereditary spastic paraparesis with spastin mutations.

BACKGROUND: Hereditary spastic paraparesis (HPS) linked to mutations in the spastin gene (SPG4) is considered to be a pure form of spastic hereditary paraparesis. However, in this disease also other signs of central nervous system involvement are frequently found. METHODS: Clinical, genetical and neuroradiological investigations were carried out in a large family with autosomal dominant spastic paraparesis and in a sporadic case with spastic paraparesis. RESULTS: Additional clinical and molecular data are provided, studying other members of the same pedigree, as already described, with a five-base deletion in exon 9 of the SPG4 gene (1215-1219delTATAA) whose members show MRI anomalies that fall within the Dandy-Walker continuum. Furthermore, an unrelated female patient with hypoplasia of the cerebellar vermis is indicated, carrying a de novo previously reported mutation of the SPG4 gene (c.1741C>T p.R581X). CONCLUSIONS: Spastin may play an important role in the development of the central nervous system and in particular in the development of the structures of posterior fossa.

Antibiotic susceptibility and serotype distribution in Streptococcus pneumoniae circulating in Italy: results of the SEMPRE surveillance study (2000-2002).

During 2000-2002, 20 clinical microbiology centres collected 1623 Streptococcus pneumoniae isolates. Susceptibility to penicillin, amoxicillin, amoxicillin/clavulanic acid, cefaclor, cefuroxime, cefotaxime, clarithromycin, ciprofloxacin, levofloxacin, rifampicin and teicoplanin was determined locally by the Etest and/or by the microdilution method by three co-ordinating centres. Total resistance to penicillin increased from 15.2% to 16.1% and macrolide resistance increased from 37.9% to 43.7%. Overall, the most effective drugs (>99% susceptible strains) were amoxicillin, amoxicillin/clavulanic acid, levofloxacin and rifampicin. The most frequent serotypes were: 23F (15.8%), 3 (10.8%) 14 (9.1%), 19F (9.1%), 6B (7.2%), 19A (6.9%) and 6A (4.8%). In conclusion, penicillin and macrolide resistance is increasing in Italy, whilst fluoroquinolone currently remains active. The most common serotypes circulating are included in the heptavalent conjugate vaccine, with the exception of type 3.

Fragile X mental retardation protein (FMRP) interacting proteins exhibit different expression patterns during development.

Fragile X syndrome is caused by the lack of expression of fragile X mental retardation protein (FMRP), an RNA-binding protein involved in mRNA transport and translation. FMRP is a component of mRNA ribonucleoprotein complexes and it can interact with a range of proteins either directly or indirectly, as demonstrated by two-hybrid selection and co-immunoprecipitation, respectively. Most of FMRP-interacting proteins are RNA-binding proteins such as FXR1P, FXR2P and 82-FIP. Interestingly, FMRP can also interact directly with the cytoplasmic proteins CYFIP1 and CYFIP2, which do not bind RNA and link FMRP to the RhoGTPase pathway. The interaction with these different proteins may modulate the functions of FMRP by influencing its affinity to RNA and by affecting the FMRP ability of cytoskeleton remodeling through Rho/Rac GTPases. To better define the relationship of FMRP with its interacting proteins during brain development, we have analyzed the expression pattern of FMRP and its interacting proteins in the cortex, striatum, hippocampus and cerebellum at different ages in wild type (WT) mice. FMRP and FXR2P were strongly expressed during the first week and gradually decreased thereafter, more rapidly in the cerebellum than in the cortex. FXR1P was also expressed early and showed a reduction at later stages of development with a similar developmental pattern in these two regions. CYFIP1 was expressed at all ages and peaked in the third post-natal week. In contrast, CYFIP2 and 82-FIP (only in forebrain regions) were moderately expressed at P3 and gradually increased after P7. In general, the expression pattern of each protein was similar in the regions examined, except for 82-FIP, which exhibited a strong expression at P3 and low levels at later developmental stages in the cerebellum. Our data indicate that FMRP and its interacting proteins have distinct developmental patterns of expression and suggest that FMRP may be preferentially associated to certain proteins in early and late developmental periods. In particular, the RNA-binding and cytoskeleton remodeling functions of FMRP may be differently modulated during development.

A new family with periventricular nodular heterotopia and peculiar dysmorphic features. A probable X-linked dominant trait.

OBJECTIVE: To describe 3 sisters with brain periventricular heterotopia and peculiar dysmorphic features as a probable X-linked dominant trait. DESIGN: Clinical, laboratory, neurophysiological, and brain imaging data were studied. SETTING: Research institute for mental retardation. PATIENTS: The 3 sisters had mental retardation, drug-resistant epilepsy, gray matter heterotopia, and peculiar malformations (low nasal bridge, upslanting palpebral fissures, palpebral edema, attached hypoplastic earlobes, thickened calvaria, rectal fibrovascular polyps, urinary tract anomalies, and increased foot length). The patients were 35, 30, and 25 years old and belonged to a sibship of 6, born of nonconsanguineous healthy parents. CONCLUSION: The 3 patients constitute a well-defined clinical entity not previously described of a probable X-linked dominant nature.

Familial cortical tremor, epilepsy, and mental retardation: a distinct clinical entity?

OBJECTIVE: To describe a European family with cortical tremor, epilepsy, and mental retardation, the pedigree of which indicates an autosomal dominant inheritance of the disease. DESIGN: Clinical, laboratory, neurophysiological, and neuroimaging data were studied. SETTING: Institute for research on mental retardation. PATIENTS: Two siblings (aged 25 and 28 years) and their 49-year-old mother had postural and action tremor, seizures, and mental retardation. Only tremor was present in the maternal grandmother (aged 68 years). The electroencephalogram showed diffuse spike-and-wave complexes and/or posterior spikes, and a photoparoxysmal response in the 4 subjects. The typical electrophysiologic features of cortical reflex myoclonus, such as giant somatosensory evoked potentials, enhancement of the C-reflex, and jerk-locked premyoclonus spikes, were found in all patients. CONCLUSION: This syndrome may represent a specific form of familial cortical tremor with a benign form of epilepsy and a new genetic model of cortical hyperexcitability inherited with an autosomal dominant mechanism.

The evolutionary conservation of the human chitotriosidase gene in rodents and primates.

Chitinases have been identified in a variety of organisms ranging from prokaryotes to eukaryotes, known to specifically degrade chitin, an abundant polymer of N-acetylglucosamine. Recently a human chitinolytic enzyme called CHIT1 was discovered. CHIT1 is expressed by activated macrophages and hydrolyzes artificial chitotrioside substrates, but its specific function in humans is unknown, since it is generally believed that man completely lacks endogenous chitin and endogenous substrates for chitinases. An intriguing question is whether the chitotriosidase activity is just an evolutionary remnant or it has a physiological function in man. To test these hypotheses we utilized a "phylogenomic" approach performing accurate sequence analyses of this gene, coding for CHIT1, in rodents and primates. Inspecting the sequences available in public databases, we determined that this gene is conserved in rodents (mouse and rat) and primates (chimpanzee, gorilla, orangutan, gibbon, baboon, a common marmoset and black macaque). Moreover we found that a 24-base pair duplication that determines an enzymatically inactive human protein is not present in primates, suggesting that this polymorphism was created during human evolution. These results indicate that chitotriosidase is conserved across the evolutionary scale. Such conservation of the CHIT1 gene argues in favour of an important biological role.

Prolactin induces chitotriosidase gene expression in human monocyte-derived macrophages.

Human chitotriosidase (Chit), a chitinolytic enzyme, is a member of the chitinase family. In human's plasma Chit activity have been proposed as a biochemical marker of macrophage activation in several lysosomal diseases. Recently we found that Chit activity is higher in patients affected by Plasmodium falciparum malaria infection suggesting that chitotriosidase may induce an immunological response. The pituitary hormone prolactin (PRL) is a multifunctional polypeptide also produced by immune cells and represents a key component of the neuroendocrine-immune loop. The presence of PRL receptors in macrophage suggests that PRL is involved in regulating functions in these cells. Our objective in this study was to investigate the effect of PRL in human monocyte-derived macrophages (HMMs) on Chit production. Administration of PRL in HMMs was found to increase both expression and activity of Chit in a time and dose dependent manner as quantified, respectively, by real time PCR and Chit activity assay. PRL-treated monocyte-derived macrophages showed also an enhanced release of superoxide anion (O2-) release. Our observations confirm that PRL regulates HMMs activation and suggest, for the first time, that it influences immune function also through the induction of Chit activity.

Comparison of rest-redistribution thallium-201 imaging and reinjection after stress-redistribution for the assessment of myocardial viability in patients with left ventricular dysfunction secondary to coronary artery disease.

Thallium (Tl)-201 reinjection after stress-redistribution (RI) imaging has been proven to accurately identify ischemic and viable myocardium. Quantitative Tl-201 analysis after stress has also shown viable myocardium in most mild to moderate (51% to 85% of normal uptake) irreversible Tl-201 defects. However, if the main clinical question is whether a region is viable, and not whether there is inducible ischemia, a resting protocol may be more appropriate. The aim of this study was to determine whether rest-redistribution (RD) quantitative Tl-201 single-photon emission tomographic imaging provides the same information on viable myocardium as Tl-201 RI. Thus, 15 patients (mean age 58 +/- 9 years) with chronic coronary artery disease and left ventricular dysfunction (ejection fraction 35 +/- 8%) were studied by both RI and RD Tl-201 single-photon emission tomography. Regional Tl-201 uptake was assessed quantitatively using a 16-segment model. When Tl-201 images were classified as normal/reversible (viable) or irreversible (nonviable), RI showed viable myocardium in 145 of 240 myocardial regions (60%), whereas RD showed it in 103 of 240 myocardial regions (43%). The 2 imaging protocols provided concordant information in 176 of 240 myocardial regions (73%). Among the 64 (27%) discordant regions, 53 (22%) were viable by RI and nonviable by RD, whereas 11 (5%) were viable by RD and nonviable by RI (p < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Incremental prognostic value of technetium-99m-tetrofosmin exercise myocardial perfusion imaging for predicting outcomes in patients with suspected or known coronary artery disease.

Technetium-99m (Tc-99m)-tetrofosmin is a radio isotope that has been shown to be an accurate alternative to thallium-201 for detecting coronary artery disease. However, its prognostic value is less well determined. To this end, 459 consecutive patients (mean age 58 +/- 10 years) with suspected or known coronary artery disease underwent exercise single-photon emission tomography Tc-99m-tetrofosmin scintigraphy. Follow-up, defined as the time from scanning until a soft event (revascularization procedures), a hard event (myocardial infarction and cardiac death), or patient response, lasted up to 78 months (median 38). An ischemic scintigraphic perfusion score, which takes into account both the extent and severity of reversible perfusion defects, was calculated to estimate the severity of perfusion abnormalities. Patients with normal scans were at low risk of events (yearly hard event rate 0.5% and soft event rate 0.9%). The rate of outcomes increased significantly with abnormal scans (yearly hard event rate 4.9% and soft event rate 10.3%). Statistical analysis using the Kaplan-Meyer survival curves showed a significant difference in event-free survival between patients with normal and abnormal scans. With use of Cox proportional-hazards analysis, after adjusting for prescan information, nuclear data provided incremental prognostic value for hard events (clinical and exercise data vs nuclear data; chi-square = 15.5 vs 33.4, p <0.001). Exercise single-photon emission tomographic scintigraphy using Tc-99m-tetrofosmin provides significant independent information on the subsequent risk of hard and soft events. The annual event rate for hard and soft events is <1% for patients with a normal scan. Furthermore, this tracer yields incremental prognostic information in addition to that provided by clinical and exercise data for hard events.

Comparison between the results of an automatic and a visual scoring of sleep EEG recordings.

In this paper, results from the visual scoring of nocturnal polygraphic recordings, carried out by nine different groups of readers from different Italian sleep laboratories, are analyzed; inter-and intragroup variability is shown and statistically discussed. Data are then compared with the results of an automatic scoring of the same recordings, carried out by the Medilog Sleep Stager. The validity of this automatic method of scoring is discussed. Finally, an epoch by epoch analysis is described, with the aim of achieving a more detailed evaluation of the intergroup variability.

Butoctamide hydrogen succinate and intensive learning sessions: effects on night sleep of Down's syndrome patients.

Mentally retarded children present a reduction in percentage of REM sleep and of oculomotor frequencies. These sleep patterns are probably relevant for their cognitive activities. The effects of butoctamide hydrogen succinate and intensive learning sessions on the night sleep of five Down's syndrome patients was studied by the authors. They found an increase in percentage of REM sleep after pharmacological treatment and an increase in oculomotor frequencies after learning sessions. The authors' hypotheses of REM sleep as a neurophysiological indicator of cerebral "plasticity" and of oculomotor frequencies as an indicator of "organization" abilities are discussed in this article. Pedagogical implications and therapeutical perspectives are also outlined.