Phosphatidylinositol 4,5-bisphosphate regulates inspiratory burst activity in the neonatal mouse preBötzinger complex.

Neurons of the preBötzinger complex (preBötC) form local excitatory networks and synchronously discharge bursts of action potentials during the inspiratory phase of respiratory network activity. Synaptic input periodically evokes a Ca(2+)-activated non-specific cation current (I(CAN)) postsynaptically to generate 10-30 mV transient depolarizations, dubbed inspiratory drive potentials, which underlie inspiratory bursts. The molecular identity of I(CAN) and its regulation by intracellular signalling mechanisms during inspiratory drive potential generation remains unknown.

Inspiratory bursts in the preBötzinger complex depend on a calcium-activated non-specific cation current linked to glutamate receptors in neonatal mice.

Inspiratory neurons of the preBötzinger complex (preBötC) form local excitatory networks and display 10-30 mV transient depolarizations, dubbed inspiratory drive potentials, with superimposed spiking. AMPA receptors are critical for rhythmogenesis under normal conditions in vitro but whether other postsynaptic mechanisms contribute to drive potential generation remains unknown. We examined synaptic and intrinsic membrane properties that generate inspiratory drive potentials in preBötC neurons using neonatal mouse medullary slice preparations that generate respiratory rhythm.

Neurokinin receptor-expressing pre-botzinger complex neurons in neonatal mice studied in vitro.

Breathing in mammals depends on inspiratory-related neural activity generated in the pre-Bötzinger complex (preBötC), where neurokinin receptor-expressing neurons (NKR(+)) have been hypothesized to play a critical rhythmogenic role. Currently, the extent to which the preBötC is populated by rhythmogenic NKR(+) neurons and whether neurons without neurokinin receptor expression (NKR(-)) share similar electrical properties with NKR(+) neurons are not well understood. These interrelated problems must be resolved to understand the widespread excitatory effects of neuropeptides and the mechanism of respiratory rhythmogenesis.

Role of persistent sodium current in mouse preBötzinger Complex neurons and respiratory rhythm generation.

Breathing movements in mammals depend on respiratory neurons in the preBötzinger Complex (preBötC), which comprise a rhythmic network and generate robust bursts that form the basis for inspiration. Persistent Na(+) current (I(NaP)) is widespread in the preBötC and is hypothesized to play a critical role in rhythm generation because of its subthreshold activation and slow inactivation properties that putatively promote long-lasting burst depolarizations. In neonatal mouse slice preparations that retain the preBötC and generate a respiratory-related rhythm, we tested the role of I(NaP) with multiple Na(+) channel antagonists: tetrodotoxin (TTX; 20 nM), riluzole (RIL; 10 microM), and the intracellular Na(+) channel antagonist QX-314 (2 mM).

[The role of the occupational health physician in the implementation of the European and Italian regulations on mechanical vibration at work].

The European Directive 2002/44/EC and the Italian Decree 187/2005 establish the minimum health and safety requirements regarding the exposure of workers to the risks arising from mechanical vibration. Excessive exposure to hand-arm vibration from powered processes or tools can cause disorders in the vascular, neurological and musculoskeletal systems of the upper limbs. Long-term occupational exposure to intense whole-body vibration is associated with an increased risk for disorders of the lumbar spine and the connected nervous system.

Different perception of cognitive impairment, behavioral disturbances, and functional disabilities between persons with mild cognitive impairment and mild Alzheimer's disease and their caregivers.

Insight in dementia is a multifaceted concept and ability, which includes the persons' perception of their behavioral and cognitive symptoms and functional disability. This ability seems to deteriorate as dementia progresses. The aim of this study was to evaluate the level of insight in the cognitive, behavioral, and functional disorders in a group of persons with mild cognitive impairment (MCI) or mild AD (Alzheimer's disease) and to compare their perception of their illness with that of their caregivers.

Contribution of spike timing to the information transmitted by HVC neurons.

In many species, neurons with highly selective stimulus-response properties characterize higher order sensory areas and/or sensory motor areas of the CNS. In the songbird nuclei, the responses of HVC (used as a proper name) neurons during playback of the bird's own song (BOS) are probably one of the most striking examples of selectivity for natural stimuli. We examined here to what extent spike-timing carries information about natural and time-reversed versions of the BOS.

Stiff person syndrome and motor mononeuropathy with conduction block: a singular association.

The "Stiff person syndrome"(SPS) is a rare dysimmune chronic neurological disorder, sometimes paraneoplastic, characterized by progressive stiffness, painful persistent or spasmodic muscle contractions, mostly involving spine and lower extremities. In 60 to 90 percent of cases, non-paraneoplastic forms are associated to the presence of anti-glutamic acid decarboxylase (anti-GAD) antibodies in the cerebrospinal fluid and in the serum, while anti-amphiphysin antibodies are frequently associated to paraneoplastic types. The relevant treatment consists of three basic approaches: increase in the inhibitory processes in charge of muscle activity control, re-modulation of the immune response, removal of any associated neoplasia.

Looking for inspiration: new perspectives on respiratory rhythm.

Recent experiments in vivo and in vitro have advanced our understanding of the sites and mechanisms involved in mammalian respiratory rhythm generation. Here we evaluate and interpret the new evidence for two separate brainstem respiratory oscillators and for the essential role of emergent network properties in rhythm generation. Lesion studies suggest that respiratory cell death might explain morbidity and mortality associated with neurodegenerative disorders and ageing.

The selectivity of canary HVC neurons for the Bird's Own Song: rate coding, temporal coding, or both?

The neuronal selectivity observed in the avian song system for the Bird's Own Song progressively emerged as an extraordinary fruitful model to investigate the neural code underlying the recognition of complex stimuli and the occurrence of learned behaviors. In adult zebra finch, neurons from the HVC (used as a proper name) show very selective auditory responses, firing more to presentation of the Bird's Own Song (BOS) than to reverse BOS or other conspecific songs. However, as adult zebra finches always produce the same stereotyped song, the presence of such highly selective neurons in birds with larger repertoire still remains an open question.

Cerebellar subacute syndrome due to corticosteroid-responsive encephalopathy associated with autoimmune thyroiditis (also called "Hashimoto's encephalopathy").

The corticosteroid-responsive encephalopathy associated with autoimmune thyroiditis (the so-called "Hashimoto's Encephalopathy") is a rare disorder with multiple symptomatology, breaking out with an acute or subacute onset and having a relapsing course, not correlated to thyroid hormone levels, with autoimmune pathogenesis, and usually associated with Hashimoto's thyroiditis. In this paper, we report on a case study regarding a 46 year-old woman showing a subacute course cerebellar syndrome, associated with Hashimoto's thyroiditis, diagnosed as "Hashimoto's encephalopathy". The possible pathogenesis and the major aspects of the differential diagnostic sector are discussed with particular reference to an ataxic syndrome caused by a progressive non-familial adult onset cerebellar degeneration (PNACD), associated with the thyroid disease itself.

Selectivity of canary HVC neurons for the bird's own song: modulation by photoperiodic conditions.

To what extent seasonal factors modify the neuronal functional properties within the nuclei of the avian song system remains an open question. In adult songbirds, neurons of the song premotor nucleus HVC (used as a proper name) exhibit selective responses for the bird's own song (BOS). Here we examine whether, outside the breeding season, when songs are less stereotyped, HVC neurons of male canaries still respond selectively to the BOS produced during this period.

A follow up study of vibration induced white finger in compensation claimants.

Aims: To follow up vibration induced white finger (VWF) in a selected group of 73 vibration exposed workers who claimed unsuccessfully for VWF compensation at a first examination.

Methods: The VWF claimants were sent to our unit by the National Insurance Institute. The basic compensatory criteria included a positive history of VWF and abnormal cold response of the digital arteries.

Sodium and calcium current-mediated pacemaker neurons and respiratory rhythm generation.

The breathing motor pattern in mammals originates in brainstem networks. Whether pacemaker neurons play an obligatory role remains a key unanswered question. We performed whole-cell recordings in the preBotzinger Complex in slice preparations from neonatal rodents and tested for pacemaker activity.

Estimating action potential thresholds from neuronal time-series: new metrics and evaluation of methodologies.

The estimation of action potential thresholds is a subjective process, which we quantified by surveying experienced electrophysiologists via a software application that allowed them to select action potential thresholds from several presented neuronal time series. Independent of this survey, we derived two nonparametric techniques for automating the detection of an action potential threshold from the time-series of intracellular recordings. Both methods start with a phase-space representation of the action potential (dV/dt versus V).

Stress in the caregivers of Alzheimer's patients: an experimental investigation in Italy.

In Italy, the family constitutes the major caregiving response to the needs of the elderly who are no longer self-sufficient. These caregivers are often wives or daughters who have chosen to keep the patient at home with them. On average, three-quarters of the caregiver's day is devoted to the patient, a proportion that tends to increase linearly as the disease progresses.

[A follow-up study of lung function among ex-asbestos workers with and without pleural plaques].

Background: Pulmonary function testing is widely accepted as an integral part of medical surveillance of occupational lung diseases. There are several cross-sectional studies evaluating lung function among asbestos-exposed workers, but only few longitudinal surveys have been performed.

Objectives: To evaluate, over a mean follow-up period of 3.

[Pleural plaques and ventilatory function: follow-up study].

We have evaluated, over a mean follow up period of 3.7 (SD 1.8) years, the lung function in a group of 103 workers, according to the presence (36 workers) or absence (67 workers) of pleural plaques at chest Rx-films/HRCT.

[Follow-up of symptoms, parameters of respiratory function, and data on specific sensitization in a group of subjects with latex-induced asthma and rhinitis].

We re-investigated 13 workers 6 years (SD 2) after the first diagnosis of asthma or rhinitis caused by latex, to update the exposure to latex, the eventual symptoms, respiratory function (spirometry and metacholine PD20 FEV1), skin prick test to common allergens and latex, RAST to latex, total IgE levels and eosinophils count in the blood. At the follow up, all the workers stopped wearing powdered latex gloves, but for 10 an indirect exposure to latex was still possible. All cases referred improvement of respiratory symptoms at work, but 7 workers occasionally complained of mild symptoms.

[Burning mouth syndrome].

Burning Mouth Syndrome (BMS) is a frequent disease characterized by a burning or painful sensation in the tongue and/or other oral sites without clinical mucosal abnormalities or lesions. The etiopathology is unknown although local, systemic and psychological factors have been connected with BMS. As this syndrome is a multifactorial disease, the diagnostic and therapeutic approach should be multidisciplinary.

Phenolic compounds and antioxidant activity from red grape marc extracts.

The aims of this work were to determine the amounts of the different classes of phenolic compounds in an ethanolic extract from red grape marc and its components, peels and seeds, and to evaluate their antioxidant activities by the beta-carotene bleaching test for their utilization as natural antioxidants. The results showed that red grape marc was rich in polyphenol compounds with a clear antioxidant activity. The extracts, in fact, at very low concentration (20 ppm) in total phenols showed an antioxidant activity (AA) higher than 43% on average, while at higher concentration (80-160 ppm) all the fractions had an AA comparable to that of butlylated-hydroxytoluene.

Sex and season influence the proportion of thin spike cells in the canary HVc.

In songbirds, anatomical attributes of song nuclei exhibit sexual and seasonal differences. To extend these data to physiological correlates, neurons ( n= 374) were recorded in the HVc of male and female canaries during and outside the breeding period. Surprisingly, a particular type of action potential waveforms was observed more frequently in breeding than in non-breeding birds and in males than in females.

Persistent sodium current, membrane properties and bursting behavior of pre-bötzinger complex inspiratory neurons in vitro.

We measured persistent Na(+) current and membrane properties of bursting-pacemaker and nonbursting inspiratory neurons of the neonatal rat pre-Bötzinger complex (pre-BötC) in brain stem slice preparations with a rhythmically active respiratory network in vitro. In whole-cell recordings, slow voltage ramps ( View Article and Find Full Text PDF

Noradrenergic control of auditory information processing in female canaries.

An ethological procedure, based on the study of the sexual responsiveness of female canaries (Serinus canaria) to song playbacks was used to investigate the function of central noradrenergic inputs in the processing of auditory information. The effects of a noradrenergic denervation on sexual responses was analyzed in females exposed to playbacks of biological relevant auditory stimuli, i.e.