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Biomedical subjects

V La Bella

Publications and source records attributed to V La Bella.

At least 19 recordsLinked to original sources

Telephone follow-up for patients with amyotrophic lateral sclerosis.

The relentless evolution of amyotrophic lateral sclerosis (ALS), a severe neurodegenerative disorder of the upper and lower motoneurons, leads to an increasing level of disability. Most patients, during the course of the disease, become unable to attend the tertiary clinical care center and are thus prevented from enrolling in clinical trials or benefiting from specialized care and management. The main objective of this study was to verify whether the ALS functional rating scale (ALSFRS) could be reliably administered by telephone to patients, when unable to attend the ALS clinic, or to their caregivers. ALSFRS is a validated instrument that assesses the functional status and the disease progression in ALS. We first administered the functional rating scale directly in the clinic to 30 patients, with definite or probable ALS, and to their respective caregivers, and found a very high agreement between the two groups for the total score and the majority of the rating items. Next, we showed, in both patients and caregivers, a high degree of correlation between the total score of the ALSFRS measured by telephone and that reported in the clinic. This indicates that ALSFRS is a reliable instrument for monitoring the disease progression in homebound patients, even when the person contacted by telephone is the caregiver. We also performed a telephone clinic, based on an unstructured interview, with 16 ALS patients at an advanced stage of the disease and unable to attend the ALS clinic. On some occasions, the person interviewed was the caregiver. The symptoms most frequently reported were a worsening of muscle strength, swallowing and breathing problems, constipation, and inability to clear lung secretions. Several patients asked for assistive and adaptive equipment. All patients and caregivers found the telephone clinic very useful and considered it a good complement to the management and care programme.

Activities of Daily Living↗

Noninvasive positive-pressure ventilation in ALS: predictors of tolerance and survival.

OBJECTIVE: To identify factors associated with tolerance and survival after noninvasive positive-pressure ventilation (NIPPV) and to investigate the influence of NIPPV on lung function in patients with ALS. METHODS: NIPPV was offered to 71 patients with ALS in accordance with currently published guidelines. Effects of NIPPV on lung function and factors influencing tolerance and survival after NIPPV were studied. RESULTS: Forty-four patients (61.9%; 95% CI: 50.6 to 73.2) tolerated NIPPV (NIPPV use >or=4 h/day) and 27 (38.1%; 95% CI: 26.8 to 49.4) were intolerant (NIPPV use <4 h/day). Patients with mild or moderate bulbar symptoms were more likely to tolerate NIPPV than those with severe impairment (odds ratio = 6.09, 95% CI: 1.18 to 31.52, p = 0.031). After NIPPV introduction, a slower decline in forced vital capacity (FVC) was observed in tolerant vs intolerant patients (p = 0.002). The slope of FVC decline after NIPPV initiation (risk ratio [RR]: 0.78, 95% CI: 0.65 to 0.94, p = 0.01) together with NIPPV tolerance (RR: 0.32, 95% CI: 0.13 to 0.78, p = 0.013) were the only independent predictors of survival in the overall group of patients. In multivariate analysis, body mass index was the most powerful predictor of longer survival after NIPPV in tolerant patients (RR: 0.77, 95% CI: 0.61 to 0.96, p = 0.022). CONCLUSION: Survival after noninvasive ventilation was independently related to ventilatory use (>or=4 h/day) and to the modifications of forced vital capacity decline after treatment initiation. The severity of bulbar impairment and the nutritional status of the ALS patients at the introduction of ventilation may predict tolerance and survival.

Aged↗

A novel mutation (Thr116Ile) in the presenilin 1 gene in a patient with early-onset Alzheimer's disease.

We report a novel presenilin 1 (PSN1) mutation (Thr116Ile) in a woman with early onset Alzheimer's disease (AD). This mutation was not found in 100 healthy controls, indicating that this is not a common polymorphism. The patient presented with forgetfulness at age 45, followed over the next 3 years by a worsening of the memory loss and frequent episodes of confusion and spatial disorientation. Neuroimaging studies were consistent with AD. The analysis of the family's pedigree showed that the proband was apparently the only member affected. Because the early death of several close relatives (i.e. the mother and the grandmother) and the demonstration that the father is not a mutation carrier, it is suggested that either a de novo mutation or a censor effect might have occurred. Our finding supports the indication that PSN1 mutations should be searched for in early-onset AD, particularly when a censor effect precludes a precise genetic analysis.

Alzheimer Disease↗

Long-term interferon-beta treatment for multiple sclerosis.

The aim of our study was to analyze the dropout rate in patients with relapsing-remitting multiple sclerosis (RRMS) under long-term treatment with the three commercially available interferon beta (IFNbeta) preparations. According to the drug taken, we divided 122 RRMS patients into 4 groups: Betaferon group, 56 patients taking INFbeta-1b (24 MIU weekly, subcutaneous injections); Avonex group, 38 patients taking IFNbeta-1a (6 MIU weekly, intramuscularly); Rebif group, 18 patients taking INFbeta-1b (18 MIU subcutaneously). Ten patients who shifted from Betaferon to Avonex were included in a fourth group. Dropouts were registered every trimester with the related cause. Data were evaluated using Kaplan-Meier survival analysis and log-rank test. During the observation period of five years, 48 patients (39.9%) dropped out: 48% of the patients in Betaferon group withdrew at a median of 758 days, 26% of the Avonex group at 356 days; 38% of the Rebif group at 421 days, and 40% of those who shifted from Betaferon to Avonex at 259 days. The differences between groups were not significant on survival analysis. Patients receiving higher dose treatment (Betaferon and Rebif groups) dropped out mainly for clinical adverse events; conversely, patients receiving lower dose therapy (Avonex group) dropped out most often for inefficacy. Patients who shifted to a lower dose treatment (fourth group) had a dropout rate similar to that of the initial treatment. Our data showed that one-third of the patients stopped the therapy, mostly for adverse events and then for inefficacy, while the remaining two-thirds were still on treatment without problems up to 5 years of follow-up. Compliance seems related to the dose of the drug, but further analysis is needed to confirm our data.

Adult↗

Bulbar-onset amyotrophic lateral sclerosis in a patient with Chiari I malformation.

We report on a patient with bulbar-onset, clinically defined, sporadic amyotrophic lateral sclerosis (ALS) who also showed a Chiari I malformation. This malformation, otherwise asymptomatic, was detected during the diagnostic work-up for ALS. To our knowledge this is the first report of an association between these two relatively uncommon disorders. Since our patient worked for many years as a bus-driver and because the ALS symptoms began in the brainstem region, we suggest that his hindbrain anomaly, along with the mechanical stress on the spine and cranio-vertebral junction due to the daily driving, might have played a role in the region-specific onset of ALS.

Amyotrophic Lateral Sclerosis↗

Expression and subcellular localization of two isoforms of the survival motor neuron protein in different cell types.

The survival motor neuron (SMN) gene is deleted or mutated in over 98% of spinal muscular atrophy patients who show specific motoneuron loss. By performing transfection experiments with rat smn cDNA, we show that two isoforms of SMN with Mr of 32 kDa and 35 kDa are produced by the same cDNA. In cultured motoneurons, both forms colocalize in coiled bodies and not in GEMS bodies as shown for HeLa cells. Subcellular fractionation of cells acutely dissociated from rat embryonic ventral spinal cord shows that the two SMN isoforms have a different subcellular localization, namely, that the 32 kDa isoform is enriched in the cytosol, whereas the 35 kDa isoform is segregating in the microsomal fraction. We show that the 35 kDa isoform of SMN is part of an insoluble complex but is absent from the cytoplasmic membranes and from the mitochondria. Immunostaining studies show that neither SMN isoform colocalizes with Bcl-2, the mitochondrial antiapoptotic protein suggested to bind to SMN in HeLa cells. Our results show that the isoforms of SMN protein have different subcellular localization and may therefore play independent biological roles. Moreover, the absence of colocalization of SMN with Bcl-2 in motoneurons suggests that some of the interactors of SMN may vary depending on the cell type, and this underscores the importance of identifying motoneuron-specific SMN interactors.

3T3 Cells↗

Differential effect of beta-N-oxalylamino-L-alanine, the Lathyrus sativus neurotoxin, and (+/-)-alpha-amino-3-hydroxy-5-methylisoxazole-4-propionate on the excitatory amino acid and taurine levels in the brain of freely moving rats.

We studied the effect of beta-oxalylamino-L-alanine, a glutamate analog present in Lathyrus sativus seeds and implicated in the etiopathogenesis of neurolathyrism, and (+/-)-alpha-amino-3-hydroxy-5-methylisoxazole-4-propionate on the extracellular levels of aspartate, glutamate and taurine in the primary motor cortex of freely moving rats. We found that while both neurotoxins increase the level of aspartate and glutamate, only (+/-)-alpha(-amino-3-hydroxy-5-methylisoxazole-4-propionate is able to modulate the level of taurine. GYKI-52466, a non-competitive non-NMDA antagonist, inhibited beta-oxalylamino-L-alanine-induced increase of aspartate, but not that of glutamate. Conversely, this antagonist proved to be very efficient in blocking the stimulating effect of (+/-)-alpha-amino-3-hydroxy-5-methylisoxazole-4-propionate on all three amino acids. We suggest that beta-oxalylamino-L-alanine increases the level of glutamate in vivo by a mechanism not connected to its effect on the non-NMDA receptors, which might involve the inhibition of glutamate transport. This would allow the excitatory neurotransmitter to reach a concentration sufficient to stimulate the non-NMDA receptors, which in their turn mediate the specific release of aspartate. Although the role of aspartate as a neurotransmitter is still under discussion, it might indeed amplify the excitotoxic cascade through its action on NMDA receptors. We speculate that this sequence of events might represent an important step in the molecular cascade leading to the appearance of the selective motoneuron degeneration in neurolathyrism.

Amino Acids, Diamino↗

Subcellular distribution of survival motor neuron (SMN) protein: possible involvement in nucleocytoplasmic and dendritic transport.

Spinal muscular atrophy (SMA) is among the most common recessive autosomal diseases and is characterized by the loss of spinal motor neurons. A gene termed 'Survival of Motor Neurons' (SMN) has been identified as the SMA-determining gene. Recent work indicates the involvement of the SMN protein and its associated protein SIP1 in spliceosomal snRNP biogenesis. However, the function of SMN remains unknown. Here, we have studied the subcellular localization of SMN in the rat spinal cord and more generally in the central nervous system (CNS), by light fluorescence and electron microscopy. SMN immunoreactivity (IR) was found in the different regions of the spinal cord but also in various regions of the CNS such as the brainstem, cerebellum, thalamus, cortex and hippocampus. In most neurons, we observed a speckled labelling of the cytoplasm and a discontinuous staining of the nuclear envelope. For some neurons (e.g. brainstem nuclei, dentate gyrus, cortex: layer V) and, in particular in motoneurons, SMN-IR was also present as prominent nuclear dot-like-structures. In these nuclear dots, SMN colocalized with SIP1 and with fibrillarin, a marker of coiled bodies. Ultrastructural studies in the anterior horn of the spinal cord confirmed the presence of SMN in the coiled bodies and also revealed the protein at the external side of nuclear pores complexes, in association with polyribosomes, and in dendrites, associated with microtubules. These localizations suggest that, in addition to its involvement in the spliceosome biogenesis, the SMN protein could also play a part in nucleocytoplasmic and dendritic transport.

Animals↗

Survival motor neuron (SMN) protein in rat is expressed as different molecular forms and is developmentally regulated.

Spinal muscular atrophy (SMA) is an autosomal recessive disease characterized by a progressive degeneration of motoneurons in spinal cord and brainstem. The telomeric copy of a duplicated gene termed survival motor neuron (smn), which maps to chromosome 5q13, has been found to be deleted in most patients. The encoded gene product is a novel protein which recently has been shown to accumulate in specific nuclear organelles (gemini of coiled bodies, GEMS), and to play a part in the formation of the spliceosome complex. We have cloned and sequenced the rat smn cDNA. Antibodies generated against an N-terminus peptide recognized a main protein of 32 kDa in immunoblots of rat embryonic tissue extracts. Minor bands of 35 kDa, 45 kDa and, in perinatal muscle, of 24 kDa were also specifically detected, indicating that SMN is expressed as different molecular forms. Subcellular fractionation indicated that the 32 kDa form is mainly soluble, while the 35 kDa and 45 kDa products segregate to the microsomal-mitochondrial fraction. SMN protein is highly regulated during development: expression is high in embryonic tissues (central nervous system, muscle, lung and liver), and then progressively decreases to very low levels in most tissues of the adult. The demonstration of different molecular forms of SMN along with its developmental regulation may help to understand the contribution of this protein in the appearance of SMA phenotype.

Amino Acid Sequence↗

Dietary consumption of Lathyrus sativus seeds induces behavioral changes in the rat.

Neurolathyrism is a degenerative disorder due to an excessive consumption of Lathyrus sativus (LS) seeds, which contain the neurotoxic amino acid beta-N-oxalylamino-L-alanine. In this study, a population of Wistar rats was fed a diet with LS seeds up to 8 months. Two control groups were chosen, one receiving standard food and the other Cicer arietinum seeds (a nontoxic legume). At the end of the dietary period, the groups previously fed the seeds were switched to standard food for 1 month (wash-out). All animals were submitted to a neurological examination and observed in an open-field situation before, during the diet (at 4 and 8 months), and finally after wash-out. Neither LS-fed rats nor controls ever showed neurological deficits. By contrast, in an open-field the activity was significantly increased in the LS-eating rats at both the 4th and 8th month. The effect was indeed reversible, since it disappeared after the wash-out. It is suggested that the enhanced open-field activity seen in the LS group might indicate a reversible excitable status. However, there is no evidence at present that the behavioral changes described represent a marker of neurodegeneration in this animal species.

Animals↗

The differential in vitro stimulation of 3',5'-cyclic nucleotide phosphodiesterase by calcium binding proteins.

A heterogeneous class of proteins exhibit within their sequence a particular structure, named EF-hand, able to bind calcium with high affinity. These calcium binding proteins have been described in most cells and tissues and are suggested to work as calcium buffers, thereby participating in the regulation of calcium-dependent cellular activity. Recent circumstantial evidences suggest that calcium binding proteins may serve other functions as well, possibly as enzyme modulators. Since 3',5'-cyclic nucleotide phosphodiesterase is a well-known calmodulin-modulated enzyme, in this work we studied the effect in vitro of different purified calcium binding proteins on the activity of this enzyme. Among the proteins tested, calmodulin and recombinant rat brain parvalbumin could stimulate the 3',5'-cyclic nucleotide phosphodiesterase activity in vitro, whereas rabbit muscle parvalbumin, rat renal and brain calbindin D28K, and bovine brain S-100B were ineffective. Immunoprecipitation with the specific antiserum completely abolished either calmodulin or recombinant brain parvalbumin activation of 3',5'-cyclic nucleotide phosphodiesterase. Moreover, while the presence of calcium in the incubation mixture was critical in the calmodulin-mediated stimulation of the enzyme, it did not modify the effect of the recombinant brain parvalbumin. We suggest that, in addition to calmodulin, parvalbumin may be a regulator of 3',5'-cyclic nucleotide phosphodiesterase, and possibly of other yet to be identified enzymes in certain tissues.

3',5'-Cyclic-AMP Phosphodiesterases↗

Increased CSF glutamate following injection of ALS immunoglobulins.

To reconcile the autoimmune and excitotoxic hypotheses regarding the etiology of amyotrophic lateral sclerosis (ALS), we injected rats intraperitoneally with ALS immunoglobulins and monitored CSF glutamate, aspartate, glutamine, and glutathione. CSF glutamate was significantly increased at 24 and 72 hours compared with both basal levels and disease control injected rats. CSF aspartate was increased at 72 hours. Glutamine and glutathione were unchanged. These data suggest that ALS immunoglobulins may enhance CSF glutamate and aspartate levels and contribute to motoneuron injury.

Amyotrophic Lateral Sclerosis↗

Apoptosis induced by beta-N-oxalylamino-L-alanine on a motoneuron hybrid cell line.

It has been suggested that beta-N-oxalylamino-L-alanine, a non-protein amino acid present in the Lathyrus Sativus seeds, may play a role in the etiopathogenesis of neurolathyrism, a toxic form of motor neuron disease clinically characterized by a severe spastic paraparesis. In order to investigate the mechanisms of beta-N-oxalylamino-L-alanine-mediated cell death, we studied the effect of this neurotoxin as well as other excitatory amino acids agonists on the growth and survival of motoneuron hybrid ventral spinal cord 4.1 cells. beta-N-oxalylamino-L-alanine was toxic to ventral spinal cord 4.1 cells in a concentration-dependent fashion (0.5-10 mM). Among the excitatory amino acids tested, only glutamate (1-10 mM), quisqualate (1 mM) and, with less extent, beta-N-methylamino-L-alanine (10 mM) induced a significant reduction of cell survival. The effect of Lathyrus Sativus neurotoxin was a slow process, becoming apparent only after 24-48 h of incubation. Interestingly, a mathematical analysis applied to the time course and dose curve of beta-N-oxalylamino-L-alanine toxicity suggested that even for very low concentrations of the amino acid it is theoretically possible to predict a time-dependent effect. The cell death was not blocked by antagonists of N-methyl-D-aspartate or non-N-methyl-D-aspartate receptors; aurintricarboxylic acid and alpha-tocopherol gave a partial protection; cysteine (1 mM) prevented the toxic effect of both Lathyrus Sativus neurotoxin and glutamate as well as quisqualate. Morphologically, in the presence of either beta-N-oxalylamino-L-alanine, glutamate or quisqualate, ventral spinal cord 4.1 cells showed apoptotic features also confirmed by ISEL technique and agarose gel electrophoresis of genomic DNA. Thus, our results suggest that in ventral spinal cord 4.1 motoneuron hybrid cells, in the absence of functional synaptic excitatory amino acid receptors, beta-N-oxalylamino-L-alanine induces cell degeneration through an apoptotic mechanism, possibly mediated by a block of cystine/glutamate Xc antiporter.

Amino Acids, Diamino↗

Calbindin D28K forms a Ca(2+)-dissociable complex with mellitin in vitro.

Calbindin D28K (CB), a cytosolic calcium binding protein (CBP), forms a macromolecular complex with the polypeptide mellitin (ME) the absence of calcium, which can be reversibly dissociated by the addition of Ca2+. The molar ratio of CB:ME constituted in this complex is 1:4, suggesting that CB interacts with the tetrameric form of ME. Like free tetrameric ME, the CB:ME complex does not migrate into 15% non-denaturing polyacrylamide electrophoretic gels, although both constituents migrate normally after irreversible complex denaturation by heating in sodium dodecyl sulphate (SDS). The interaction of these two proteins can be distinguished from the association of calmodulin (CM) with ME, which forms a reversibly dissociable, equimolar complex in the presence of Ca2+ and a stable non-migrating complex (molar ratio = 1:12) in its absence. Thus, CB and CM appear to bind ME under different Ca2+ regulatory control, suggesting possible roles for CB as a Ca(2+)-dependent regulatory binding protein.

Animals↗

The role of calcium-binding proteins in selective motoneuron vulnerability in amyotrophic lateral sclerosis.

The factors contributing to selective motoneuron loss in amyotrophic lateral sclerosis (ALS) remain undefined. To investigate whether calcium-binding proteins contribute to selective motoneuron vulnerability in ALS, we compared calbindin-D28K and parvalbumin immunoreactivity in motoneuron populations in human ALS, and in a ventral spinal cord hybrid cell line selectively vulnerable to the cytotoxic effects of ALS IgG. In human autopsy specimens, immunoreactive calbindin-D28k and parvalbumin were absent in motoneuron populations lost early in ALS (i.e., cortical and spinal motoneurons, lower cranial nerve motoneurons), while motoneurons damaged late or infrequently in the disease (i.e., Onuf's nucleus motoneurons, oculomotor, trochlear, and abducens nerve neurons) expressed markedly higher levels of immunoreactive calbindin-D28K and/or parvalbumin. Motoneuron-neuroblastoma VSC 4.1 hybrid cells lost immunoreactive calbindin-D28k and parvalbumin following dibutyryl-cyclic AMP-induced differentiation and were killed by IgG from ALS patients. Undifferentiated calbindin/parvalbumin-reactive VSC 4.1 cells were not killed, nor were other cell lines expressing high levels of calbindin-D28K and parvalbumin immunoreactivity (substantia nigra-neuroblastoma hybrid cells and N18TG2 neuroblastoma parent cells). These studies suggest that decreased calbindin-D28K and parvalbumin immunoreactivity may help explain the selective vulnerability of motoneurons in ALS.

Adult↗

Effect of beta-N-oxalylamino-L-alanine on cerebellar cGMP level in vivo.

Beta-N-oxalylamino-L-alanine (BOAA), a non-protein amino acid present in the seeds of Lathyrus Sativus (LS), is one of several neuroactive glutamate analogs reported to stimulate excitatory receptors and, in high concentrations, cause neuronal degeneration. In the present study, the in vivo acute effects of synthetic BOAA and LS seed extract were investigated on rat cerebellar cyclic GMP following intraperitoneal (10-100 mg/kg) or oral (100 mg/kg) administration of subconvulsive doses of toxin. Furthermore, the BOAA content in LS seeds and in the cerebellum of injected rats was determined by high performance liquid chromatograph analysis. A dose- and time-dependent increase of cerebellar cyclic guanosine monophosphate (cGMP) level was observed after intraperitoneal administration of synthetic BOAA or LS extract. The neurotoxin evoked a maximum stimulation 90 min after injection within the dose range of 50-75 mg/kg, elevating cGMP from basal levels of 5.3 +/- 0.5 pmol/mg protein to 15 +/- 1.3 pmol/mg protein. Similarly, the oral intake of LS-extracted neurotoxin resulted in the elevation of cGMP content. Kynurenic acid (300 mg/kg i.p.), a non specific excitatory amino acid antagonist, was effective in blocking LS BOAA-elicited cGMP enhancement. The data suggest that in the cerebellum acute administration of low concentrations of BOAA exert in vivo activation of glutamate receptors involved in the regulation of cGMP level.

Administration, Oral↗