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1.
Ann Cardiol Angeiol (Paris) ; 68(3): 187-194, 2019 Jun.
Article Fr | MEDLINE | ID: mdl-30704626

Regular physical exercice has undeniable cardiovascular benefits and improves life expectancy. This benefice seems limited to moderate intensity exercises. Intense and chronic physical exercice would lead to heart structural changes. For a long time, knowledge of these cardiac effects seemed limited to the left ventricle. Since more authors have shown that right ventricle is vulnerability to the effects of intense chronic training. We report a Gallavardin-type ventricular stress tachycardia in a young with healthy hearted; in whom a right infundibular arrhythmogenic focus has been found in the absence of structural alteration of the right ventricle. Intense athletic activity may reveal a latent arrhythmogenic focus through sympathetic activation. Ablation was the preferred therapeutic strategy, preferred to drug therapy and derived from an analysis of risk-benefit ratios.


Sports/physiology , Tachycardia, Ventricular/physiopathology , Adult , Arrhythmias, Cardiac/diagnosis , Electrocardiography , Exercise Test , Female , Humans
2.
J Fr Ophtalmol ; 37(3): 231-6, 2014 Mar.
Article En | MEDLINE | ID: mdl-24576569

INTRODUCTION: The widespread use of amiodarone is limited by its toxicity, notably to the optic nerve. We report two cases of bilateral optic nerve neuropathy due to amiodarone, and provide a detailed description of the disease. OBSERVATIONS: The first case was a 59-year-old man complaining from insidious monocular loss of vision within ten months of initiating amiodarone. Funduscopy and optical coherence tomography showed bilateral optic disc edema. The second case was a 72-year-old man presenting with a decrease in visual acuity in his left eye for a month. Funduscopy showed a left optic nerve edema, and fluorescein angiography showed bilateral papillitis. In both cases, the clinical presentation was not suggestive of ischemic neuropathy, because of the preservation of visual acuity and the insidious onset. In addition, both cardiovascular and inflammatory work-up were normal. An amiodarone-associated neuropathy was suspected, and amiodarone was discontinued with the approval of the cardiologist, with complete regression of the papilledema and a stabilization of visual symptoms. DISCUSSION: Differentiating between amiodarone-associated optic neuropathy and anterior ischemic optic neuropathy may be complicated by the cardiovascular background of such patients. The major criterion is the absence of a severe decrease in visual acuity; other criteria are the normality of cardiovascular and inflammatory work-up, and the improvement or the absence of worsening of symptoms after discontinuation of amiodarone. CONCLUSION: Amiodarone-associated neuropathy remains a diagnosis of exclusion, and requires amiodarone discontinuation, which can only be done with the approval of a cardiologist, and sometimes requires replacement therapy.


Amiodarone/adverse effects , Anti-Arrhythmia Agents/adverse effects , Optic Nerve Diseases/chemically induced , Aged , Humans , Male , Middle Aged , Optic Nerve Diseases/diagnosis
3.
Neuroscience ; 223: 305-14, 2012 Oct 25.
Article En | MEDLINE | ID: mdl-22890082

Traumatic Brain injury affects at least 1.7 million people in the United States alone each year. The majority of injuries are categorized as mild but these still produce lasting symptoms that plague the patient and the medical field. Currently treatments are aimed at reducing a patient's symptoms, but there is no effective method to combat the source of the problem, neuronal loss. We tested a mild, closed head traumatic brain injury model for the effects of modulation of the antioxidant transcription factor Nrf2 by the chemical activator, tert-butylhydroquinone (tBHQ). We found that post-injury visual memory was improved by a 7 day course of treatment and that the level of activated caspase-3 in the hippocampus was reduced. The injury-induced memory loss was also reversed by a single injection at 30 min after injury. Since the protective stress response molecule, HSP70, can be upregulated by Nrf2, we examined protein levels in the hippocampus, and found that HSP70 was elevated by the injury and then further increased by the treatment. To test the possible role of HSP70, model neurons in culture exposed to a mild injury and treated with the Nrf2 activator displayed improved survival that was blocked by the HSP70 inhibitor, VER155008. Following mild traumatic brain injury, there may be a partial protective response and patients could benefit from directed enhancement of regulatory pathways such as Nrf2 for neuroprotection.


Antioxidants/therapeutic use , Brain Injuries/complications , Cognition Disorders/drug therapy , Cognition Disorders/etiology , Hydroquinones/therapeutic use , Analysis of Variance , Animals , Avoidance Learning/drug effects , Brain/metabolism , Brain/pathology , Brain Injuries/drug therapy , Caspase 3/genetics , Caspase 3/metabolism , Cell Line, Tumor , Cell Survival/drug effects , Cognition Disorders/pathology , Disease Models, Animal , Gene Expression Regulation/drug effects , Glial Fibrillary Acidic Protein/genetics , Glial Fibrillary Acidic Protein/metabolism , HSP70 Heat-Shock Proteins/antagonists & inhibitors , HSP70 Heat-Shock Proteins/genetics , HSP70 Heat-Shock Proteins/metabolism , Humans , Male , Maze Learning/drug effects , Mice , Mice, Inbred ICR , Motor Activity/drug effects , NF-E2-Related Factor 2/metabolism , Neuroblastoma/pathology , Proto-Oncogene Proteins c-jun/genetics , Proto-Oncogene Proteins c-jun/metabolism , Purine Nucleosides/pharmacology , RNA, Messenger/metabolism , Recognition, Psychology/drug effects , Rotarod Performance Test , Time Factors
4.
Epidemiol Infect ; 140(8): 1446-53, 2012 Aug.
Article En | MEDLINE | ID: mdl-22040482

The aim of the present study was to assess the recent trends in the epidemiology of non-typhoid Salmonella in Israel using a sentinel laboratory-based surveillance network. Between 1999 and 2009, 8758 Salmonella stool isolates were reported by five sentinel laboratories. There was a significant decrease in the incidence rate of Salmonella isolates from 70·5/100,000 in 1999 to 21·6/100,000 in 2005 followed by a slight increase to 30·3/100,000 in 2009. Of all Salmonella, 64·3% were isolated from children in the 0-4 years age group. Up to 2008, S. Enteritidis was the most prevalent serotype and in 2009 S. Infantis emerged as the most common Salmonella serotype. The decrease in the incidence of S. Enteritidis and S. Typhimurium and increase in S. Infantis among humans were associated with a similar trend among breeding flocks, which followed significant preventive interventions conducted against S. Enteritidis and S. Typhimurium infections in poultry. Tight surveillance and education of food handlers and consumers should be enhanced to reduce the foodborne transmission of Salmonella in Israel.


Salmonella Infections/epidemiology , Salmonella Infections/microbiology , Salmonella/classification , Salmonella/isolation & purification , Adolescent , Adult , Aged , Anti-Bacterial Agents/pharmacology , Child , Child, Preschool , Drug Resistance, Bacterial , Female , Humans , Infant , Israel/epidemiology , Male , Middle Aged , Salmonella/drug effects , Serotyping , Time Factors , Young Adult
5.
Neuroscience ; 158(2): 745-50, 2009 Jan 23.
Article En | MEDLINE | ID: mdl-19013502

Wobbler mice model motor neuron disease with a substantial decline in motor neurons. TDP-43 is a nucleic acid binding protein that accumulates, along with ubiquitin, in the cytoplasm of amyotrophic lateral sclerosis (ALS) motor neurons. Recently, it was reported that Cu/Zn superoxide dismutase type 1 (SOD1) familial amyotrophic lateral sclerosis (fALS) model mice do not mimic the TDP-43 changes seen in sporadic ALS, although they share a large number of other properties with the human disorder. We examined ubiquitin inclusions and TDP-43 expression in wobbler mice. TDP-43 mRNA, measured by quantitative reverse transcription-coupled PCR, was elevated in the wobbler spinal cord. Immunohistochemistry revealed intracellular ubiquitin inclusions and abnormal distribution of TDP-43 into the cytoplasm in wobblers similar to the staining reported in ALS. Finally, nuclear and cytoplasmic fractions, examined by Western immunoblotting, confirmed a delocalization of TDP-43 in the neurodegenerative wobbler. These observations indicate that wobbler mice, which suffer motor neuron loss at 21 days, undergo TDP-43 and ubiquitin changes characteristic of sporadic ALS.


DNA-Binding Proteins/metabolism , Motor Neuron Disease/metabolism , RNA, Messenger/metabolism , Animals , Cell Nucleus/metabolism , Cytoplasm/metabolism , DNA-Binding Proteins/genetics , Disease Models, Animal , Gene Expression Regulation/genetics , Mice , Mice, Neurologic Mutants , Motor Neuron Disease/pathology , Spinal Cord/pathology , Ubiquitin/metabolism
6.
Arch Mal Coeur Vaiss ; 98(4): 275-80, 2005 Apr.
Article Fr | MEDLINE | ID: mdl-15881841

Recently, Japanese authors have described a new clinical entity associating apical akidyskinesia and basal hyperkinesias without significant coronary artery disease under the name of the tako-tsubo syndrome. This syndrome is usually observed in elderly women and the clinical presentation is usually that of an acute coronary syndrome. The authors report 10 cases of patients investigated between June 2003 and August 2004. All patients were women with an average age of 66 +/- 15 years. Seven patients had chest pain on admission with, in three cases, signs of cardiac failure. In 8 patients, a causal factor was identified: emotional stress in 7 cases and anaphylactic shock in one case. All patients underwent coronary angiography and ventriculography which showed typical changes in left ventricular contractility without significant coronary disease. The peak CPK and troponin values were 222 +/- 115 UI/l and 3.32 +/- 1.50 microg/l, respectively. One patient died in cardiogenic shock. In the other cases, normalisation of wall motion was observed in the month following the onset of symptoms. One patient developed 3rd degree atrioventricular block and required implantation of a pacemaker. This clinical entity must be taken into consideration in elderly women with acute coronary syndromes.


Ventricular Dysfunction, Left/pathology , Age Factors , Aged , Coronary Angiography , Electrocardiography , Female , Heart Block/etiology , Humans , Middle Aged , Syndrome
7.
J Radiol ; 85(5 Pt 1): 627-33, 2004 May.
Article Fr | MEDLINE | ID: mdl-15205654

PURPOSE: To define a subgroup of patients at increased risk of renal artery stenosis (RAS) in a population of patients undergoing cardiac catheterization. MATERIALS AND METHODS: A total of 467 patients (mean age of 64 Years +/-11) underwent cardiac catheterization and aortography Results were evaluated to detect correlations between the presence or absence of RAS and clinical and biological parameters. RESULTS: A total of 42 (9%) patients had a renal artery stenosis. Univariate analysis defined parameters correlated with the presence of RAS: systolic blood pressure (p=0.03), pulse pressure (p=0.005), age (p<0.0001), creatinine clearance (p<0.0001), 2-vessel (p=0.028) and 3-vessel (p=0.037) coronary artery diseases. Multivariate analysis showed that the presence of RAS correlated to creatinine clearance (p=0.02) and 2-vessel coronary artery disease. A creatinine clearance between 30 and 60 ml/min and multi-vessel coronary artery disease defined a subgroup at increased risk of RAS with sensitivity, specificity, positive and negative predictive values of: 47.6, 90.1, 32.3 and 94.6%. The prevalence of renal artery stenosis was 5.2% when both parameters were absent. CONCLUSION: Patients with mild renal insufficiency and multi-vessel coronary artery disease defined a subgroup of patients at increased risk of RAS (32.5%) that may benefit from abdominal aortography performed at the time of cardiac catheterization.


Aortography/standards , Cardiac Catheterization , Coronary Disease , Patient Selection , Renal Artery Obstruction , Aged , Analysis of Variance , Aortography/statistics & numerical data , Blood Pressure , Comorbidity , Coronary Angiography , Coronary Disease/complications , Coronary Disease/diagnosis , Coronary Disease/epidemiology , Creatinine/metabolism , Female , Humans , Logistic Models , Male , Metabolic Clearance Rate , Middle Aged , Prevalence , Prospective Studies , Renal Artery Obstruction/complications , Renal Artery Obstruction/diagnosis , Renal Artery Obstruction/epidemiology , Renal Artery Obstruction/metabolism , Renal Insufficiency/complications , Renal Insufficiency/diagnosis , Renal Insufficiency/epidemiology , Renal Insufficiency/metabolism , Risk Factors , Sensitivity and Specificity , Severity of Illness Index , Systole
8.
Curr Drug Targets Inflamm Allergy ; 3(1): 105-14, 2004 Mar.
Article En | MEDLINE | ID: mdl-15032647

Thrombin is well known in its function as the ultimate serine protease in the coagulation cascade. Emerging evidence indicates that thrombin also functions as a potent signaling molecule that regulates physiologic and pathogenic responses alike in a large variety of cell populations and tissues. Accompanying CNS injury and other cerebral vascular damages, prothrombin activation and leakage of active thrombin into CNS parenchyma has been documented. Due to the irreplaceable feature of neurons, over-reactive inflammatory reactions in the CNS often cause irreversible neuronal damage. Therefore, particular attention is required to develop strategies that restrict CNS inflammatory responses to beneficial, in contrast to neurotoxic ones. In this regard, thrombin not only activates endothelial cells and induces leukocyte infiltration and edema but also activates astrocytes, and particularly microglia, as recently demonstrated, to propagate the focal inflammation and produce potential neurotoxic effects. Recently revealed molecular mechanisms underlying these thrombin effects appear to involve proteolytic activation of two different thrombin-responsive, protease-activated receptors (PARs), PAR1 and PAR4, possibly in concert. Potential therapeutic strategies based on appreciation of the current understanding of molecular mechanisms underlying thrombin-induced CNS inflammation are also discussed.


Inflammation Mediators/physiology , Neurodegenerative Diseases/physiopathology , Thrombin/physiology , Trauma, Nervous System/physiopathology , Animals , Anti-Inflammatory Agents/pharmacology , Central Nervous System/pathology , Central Nervous System/physiopathology , Humans , Inflammation/pathology , Inflammation/physiopathology , Peripheral Nervous System/pathology , Peripheral Nervous System/physiopathology , Thrombin/antagonists & inhibitors
9.
Int Rev Cytol ; 211: 153-77, 2001.
Article En | MEDLINE | ID: mdl-11597003

The first association of the synapse as a potential site of neurodegenerative disease burden was suggested for Alzheimer's disease (AD) almost 30 years ago. Since then protease:protease inhibitor (P:PI) systems were first linked to functional regulation of synaptogenesis and synapse withdrawal at the neuromuscular junction (NMJ) more than 20 years ago. Confirmatory evidence for the involvement of the synapse, the rate-limiting or key unit in neural function, in AD did not become clear until the beginning of the 1990s. However, over the past 15 years evidence for participation of thrombin, related serine proteases and neural PIs, homologous and even identical to those of the plasma clot cascade, has been mounting. Throughout development a balance between stabilization forces, on the one hand, and breakdown influences, on the other, becomes established at synaptic junctions, just as it does in plasma clot proteins. The formation of protease-resistant cross-links by the transglutaminase (TGase) family of enzymes may add to the stability for this balance. The TGase family includes coagulation factor XIIIA and 8 other different genes, some of which may also influence the persistence of neural connections. Synaptic location of protease-activated, G-protein-coupled receptors (PARs) for thrombin and related proteases, their serpin and Kunitz-type PIs such as protease nexin I (PNI), alpha1-antichymotrypsin (alpha-ACT), and the Kunitz protease inhibitor (KPI)-containing secreted forms of beta-amyloid protein precursor (beta-APP), along with the TGases and their putative substrates, have all been amply documented. These findings strongly add to the conclusion that these molecules participate in the eventual structural stability of synaptic connections, as they do in coagulation cascades, and focus trophic activity on surviving terminals during periods of selective contact elimination. In disease states, this imbalance is likely to be shifted in favor of destabilizing forces: increased and/or altered protease activity, enhanced PAR influence, decreased and/or altered protease inhibitor function, reduction and/or alteration in tTG expression and activity, and alteration in its substrate profile. This imbalance further initiates a cascade of events leading to inappropriate programmed cell death and may well be considered evidence of synaptic apoptosis.


Neuromuscular Junction/physiology , Neuronal Plasticity/physiology , Signal Transduction/physiology , Synapses/physiology , Thrombin/metabolism , Transglutaminases/metabolism , Amino Acid Sequence , Animals , Cell Surface Extensions/metabolism , Factor XIII/metabolism , Humans , Molecular Sequence Data , Neuromuscular Junction/cytology , Serine Endopeptidases/genetics , Serine Endopeptidases/metabolism
10.
J Neurobiol ; 48(2): 87-100, 2001 Aug.
Article En | MEDLINE | ID: mdl-11438939

Thrombin, the ultimate protease in the blood coagulation cascade, mediates its known cellular effects by unique proteolytic activation of G-protein-coupled protease-activated receptors (PARs), such as PAR1, PAR3, and PAR4, and a "tethered ligand" mechanism. PAR1 is variably expressed in subpopulations of neurons and largely determines thrombin's effects on morphology, calcium mobilization, and caspase-mediated apoptosis. In spinal cord motoneurons, PAR1 expression correlates with transient thrombin-mediated [Ca(2+)](i) flux, receptor cleavage, and elevation of rest [Ca(2+)](i) activating intracellular proteases. At nanomolar concentrations, thrombin retracts neurites via PAR1 activation of the monomeric, 21 kDa Ras G-protein RhoA, which is also involved in neuroprotection at lower thrombin concentrations. Such results suggest potential downstream targets for thrombin's injurious effects. Consequently, we employed several G-protein-specific modulators prior to thrombin exposure in an attempt to uncouple both heterotrimeric and monomeric G-proteins from motoneuronal PAR1. Cholera toxin, stimulating Gs, and lovastatin, which blocks isoprenylation of Rho, reduced thrombin-induced calcium mobilization. In contrast, pertussis toxin and mastoparan, inhibiting or stimulating G(o)/G(i), were found to exacerbate thrombin action. Effects on neuronal rounding and apoptosis were also detected, suggesting therapeutic utility may result from interference with downstream components of thrombin signaling pathways in human motor neuron disorders, and possibly other neurodegenerative diseases. Published 2001 John Wiley & Sons, Inc.


Apoptosis/drug effects , Calcium Signaling/drug effects , Hemostatics/pharmacology , Motor Neurons/metabolism , Thrombin/pharmacology , Anticholesteremic Agents/pharmacology , Caspase Inhibitors , Cell Line , Cholera Toxin/pharmacology , Cysteine Proteinase Inhibitors/pharmacology , GTP-Binding Proteins/metabolism , Intercellular Signaling Peptides and Proteins , Lovastatin/pharmacology , Motor Neurons/drug effects , Motor Neurons/ultrastructure , Neurites/drug effects , Neurites/physiology , Oligopeptides/pharmacology , Peptides , Pertussis Toxin , Receptor, PAR-1 , Receptors, Thrombin/metabolism , Virulence Factors, Bordetella/pharmacology , Wasp Venoms/pharmacology
11.
Am J Cardiol ; 87(6): 693-8, 2001 Mar 15.
Article En | MEDLINE | ID: mdl-11249885

The purpose of this study was to compare the effects of stent placement with and without balloon predilatation on duration of the procedure, reduction of procedure-related costs, and clinical outcomes. Although preliminary trials of direct coronary stenting have demonstrated promising results, the lack of randomized studies with long-term follow-up has limited the critical evaluation of the role of direct stenting in the treatment of obstructive coronary artery disease. Between January and September 1999, 338 patients were randomly assigned to either direct stent implantation (DS+; 173 patients) or standard stent implantation with balloon predilatation (DS-; 165 patients). Baseline clinical and angiographic characteristics were similar in the 2 groups. Procedural success was achieved in 98.3% of patients assigned to DS+ and 97.5% of patients assigned to DS- (p = NS), with a crossover rate of 13.9%. Compared with DS-, DS+ conferred a dramatic reduction in procedure-related cost ($956.4 +/- $352.2 vs $1,164.6 +/- $383.9, p <0.0001) and duration of the procedure (424.2 +/- 412.1 vs 634.5 +/- 390.1 seconds, p < 0.0001). At 6-month follow-up, the incidence of major adverse cardiac events including death, angina pectoris, myocardial infarction, congestive heart failure, repeat angioplasty, or coronary artery bypass graft surgery was 5.3% in DS+ and 11.4% in DS- (p = NS). Multivariate analysis demonstrated that major adverse cardiac events rates were related to stent length of 10 mm (relative risk [RR] 3.25, 95% confidence intervals [CI] 1.36 to 7.78; p = 0.008), stent diameter of 3 mm (RR 2.69, 95% CI 1.03 to 7.06; p = 0.043), and complex lesion type C (RR 2.83, 95% CI 1.02 to 7.85; p = 0.045). Thus, in selected patients, this prospective randomized study shows the feasibility of DS+ with reduction in procedural cost and length, and without an increase in in-hospital clinical events and major adverse cardiac events at 6-month follow-up.


Angina Pectoris/therapy , Angioplasty, Balloon, Coronary , Stents , Angina Pectoris/diagnostic imaging , Angina Pectoris/economics , Angina Pectoris/mortality , Angioplasty, Balloon, Coronary/adverse effects , Angioplasty, Balloon, Coronary/economics , Coronary Angiography , Cost Savings , Feasibility Studies , Female , Humans , Male , Middle Aged , Multivariate Analysis , Prospective Studies , Risk Factors , Stents/adverse effects , Stents/economics , Survival Rate
12.
Ann Thorac Surg ; 72(6): 2132-4, 2001 Dec.
Article En | MEDLINE | ID: mdl-11789816

Spontaneous intramural left atrial hematoma is very rare. We describe a case of spontaneous intramural left atrial hematoma that had to be semiurgently resected. Postoperatively, the patient was diagnosed as having systemic immunocyte-derived (AL) amyloidosis, because of rare manifestations of fatal bleeding. Though spontaneous intramural left atrial hematoma is one of the severe complications of systemic AL amyloidosis, we believe that amyloid deposits caused fragility of the left atrial wall.


Amyloidosis/surgery , Cardiomyopathies/surgery , Heart Atria/surgery , Hematoma/surgery , Aged , Amyloidosis/pathology , Cardiomyopathies/pathology , Diagnosis, Differential , Heart Atria/pathology , Hematoma/pathology , Humans , Male , Tomography, X-Ray Computed
13.
J Interv Cardiol ; 14(1): 1-5, 2001 Feb.
Article En | MEDLINE | ID: mdl-12053317

The Tenax coronary stent is laser sculpted from high precision 316 L stainless steel using advanced production procedures. An a-SiC: H (hydrogen-rich amorphous silicon carbide) coating reduces its thrombogenicity and improves its biocompatibility. From April to July 1998, 266 stents were implanted in 241 patients (aged 62.7 +/- 10.5 years) in five centers. The clinical indication for intervention was unstable angina (33.2%) and recent myocardial infarction (29.5%) in many cases. Most lesions (53.8%) had complex characteristics (Class B2 or C). The target vessel was the LAD in 42.5% and the right coronary artery in 36.8% of all cases. Four primary stent deployment failures occurred and implantation was successful in 259 (97.4%) of 266 stents. No death and no Q-wave myocardial infarction or emergency CABG occurred during hospital stay. Clinical success, defined as successful deployment without procedural or clinical event, was achieved in 230 (95.4%) of 241 patients. One-year clinical follow-up shows a low need for target lesion revascularization (17/237 [7.1%] patients) and a 15.8% rate of major adverse cardiac events (36/237 patients). The clinical and angiographic outcomes of our study suggest that the hybrid, amorphous hydrogenated silicon carbide coated design is promising and merits further evaluation in larger clinical trials.


Angina, Unstable/therapy , Biocompatible Materials , Carbon Compounds, Inorganic , Coated Materials, Biocompatible , Coronary Vessels , Myocardial Infarction/therapy , Silicon Compounds , Stainless Steel , Stents , Aged , Female , Follow-Up Studies , Humans , Male , Middle Aged
14.
J Biol Chem ; 276(5): 3295-301, 2001 Feb 02.
Article En | MEDLINE | ID: mdl-11013236

In order to understand the mechanism for insoluble neurotoxic protein polymerization in Alzheimer's disease (AD) brain neurons, we examined protein and gene expression for transglutaminase (TGase 2; tissue transglutaminase (tTG)) in hippocampus and isocortex. We found co-localization of tTG protein and activity with tau-positive neurofibrillary tangles, whereas mRNA and sequence analysis indicated an absolute increase in tTG synthesized. Although apoptosis in AD hippocampus is now an established mode of neuronal cell death, no definite underlying mechanism(s) is known. Since TGase-mediated protein aggregation is implicated in polyglutamine ((CAG)(n)/Q(n) expansion) disorder apoptosis, and expanded Q(n) repeats are excellent TGase substrates, a role for TGase in AD is possible. However, despite such suggestions almost 20 years ago, the molecular mechanism remained elusive. We now present one possible molecular mechanism for tTG-mediated, neurotoxic protein polymerization leading to neuronal apoptosis in AD that involves not its substrates (like Q(n) repeats) but rather the unique presence of alternative transcripts of tTG mRNA. In addition to a full-length (L) isoform in aged non-demented brains, we found a short isoform (S) lacking a binding domain in all AD brains. Our current results identify intron-exon "switching" between L and S isoforms, implicating G-protein-coupled signaling pathways associated with tTG that may help to determine the dual roles of this enzyme in neuronal life and death processes.


Alzheimer Disease/enzymology , Transglutaminases/genetics , tau Proteins/metabolism , Alternative Splicing/genetics , Alzheimer Disease/genetics , Alzheimer Disease/metabolism , Amino Acid Sequence , Base Sequence , Brain/enzymology , Brain/metabolism , DNA, Complementary/analysis , Exons , Humans , Introns , Molecular Sequence Data , Neurons/metabolism , Protein Binding , RNA, Messenger/analysis , RNA, Messenger/biosynthesis , Reverse Transcriptase Polymerase Chain Reaction , Sequence Analysis, DNA , Time Factors , Transglutaminases/metabolism
15.
Exp Neurol ; 166(2): 213-26, 2000 Dec.
Article En | MEDLINE | ID: mdl-11085887

Although the precise mechanisms explaining loss of, and failure to regain, function after spinal cord injury are unknown, there is increasing interest in the role of "secondary cell death." One prevalent theme in cell loss in other regions of the CNS involves apoptosis executed by the intracellular caspase proteases. A recent study demonstrated that spinal cord injury rapidly increased the activation of caspase-3. Our previous studies demonstrated peak apoptosis in three of four cellular compartments 3 days after controlled contusion in the rat. We have extended these analyses to include enzyme and substrate studies of caspase subfamilies both in rostral and in caudal adjacent segments compared to the lesion site. Although presumed activation of programmed proenzyme is considered the mechanism for enhanced caspases, our novel analyses were designed to detect upregulation of gene expression. We surveyed traumatically injured spinal cord for caspase family messages with a modified differential mRNA display approach and found that the caspase-3 (CASP3) message was present and upregulated severalfold after injury. Our results clearly demonstrate that cell death in the spinal cord occurs after posttranslational activation of caspases that follow, at least for caspase-3, initial upregulation of CASP3 mRNA levels.


Apoptosis/physiology , Caspases/metabolism , Spinal Cord Injuries/metabolism , Spinal Cord Injuries/pathology , Spinal Cord/enzymology , Spinal Cord/pathology , Animals , Biotin , Carrier Proteins/metabolism , Caspase 3 , Caspases/genetics , Cysteine Proteinase Inhibitors , Gene Expression Profiling , Gene Expression Regulation, Enzymologic , In Situ Hybridization , Male , Microfilament Proteins/metabolism , Microglia/metabolism , Motor Neurons/enzymology , Motor Neurons/pathology , Oligopeptides , Poly (ADP-Ribose) Polymerase-1 , Poly(ADP-ribose) Polymerases , Proteins/metabolism , RNA, Messenger/analysis , Rats , Rats, Sprague-Dawley , Substrate Specificity
16.
Mol Med ; 6(5): 410-29, 2000 May.
Article En | MEDLINE | ID: mdl-10952021

BACKGROUND: Mechanisms underlying neurodegeneration are actively sought for new therapeutic strategies. Transgenic, knockout and genetic mouse models greatly aid our understanding of the mechanisms for neuronal cell death. A naturally occurring, autosomal recessive mutant, known as wobbler, and mice transgenic for familial amyotrophic lateral sclerosis (FALS) superoxide dismutase (SOD)1 mutations are available, but the molecular mechanisms remain equally unknown. Both phenotypes are detectable after birth. Wobbler is detectable in the third week of life, when homozygotes (wr/wr) exhibit prominent gliosis and significant motor neuron loss in the cervical, but not in lumbar, spinal cord segments. To address molecular mechanisms, we evaluated "death signals" associated with the multifunctional serine protease, thrombin, which leads to apoptotic motor neuronal cell death in culture by cleavage of a G-protein coupled, protease-activated receptor 1 (PAR-1). MATERIALS AND METHODS: Thrombin activities were determined with chromogenic substrate assays, Western immunoblots and immunohistochemistry were performed with anti-PAR-1 to observe localizations of the receptor and anti-GFAP staining was used to monitor astrocytosis. PAR-1 mRNA levels and locations were determined by reverse transcription polymerase chain reaction (qRT-PCR) and in situ hybridizations. Cell death was monitored with in situ DNA fragmentation assays. RESULTS: In preliminary studies we found a 5-fold increase in PAR-1 mRNA in cervical spinal cords from wr/wr, compared with wild-type (wt) littermates. Our current studies suggested that reactive astrocytosis and motor neuron cell death were causally linked with alterations in thrombin signaling. PAR-1 protein expression was increased, as demonstrated by immunocytochemistry and confirmed with in situ hybridization, in phenotypic wr/wr motor neurons, compared with wt, but not in astrocytes. This increase was much greater in cervical, compared with lumbar, segments, paralleling motor neuron degeneration. We also found, using reverse transcription polymerase chain reaction (qRT-PCR) with RNA from genotyped embryos, that PAR-1 was already increased in wr/wr cords at E12, the earliest time examined. CONCLUSIONS: Thus, motor neuron degeneration and death follows PAR-1 expression both temporally and topographically in wobbler mice. Since our culture studies show that thrombin mobilized [Ca2+]i by activating PAR-1, eventually leading to motor neuron apoptosis, up-regulation of PAR-1 during development may contribute both to "appropriate" as well as "inappropriate" neuronal death in wobbler.


Motor Neurons/physiology , Receptors, Thrombin/genetics , Spinal Cord/pathology , Transcription, Genetic , Animals , Cell Death , Crosses, Genetic , DNA Probes , Female , Genotype , Glial Fibrillary Acidic Protein/analysis , Gliosis , Homozygote , Humans , Male , Mice , Mice, Knockout , Mice, Transgenic , Motor Neuron Disease/genetics , Motor Neuron Disease/physiopathology , Motor Neurons/cytology , Motor Neurons/pathology , RNA, Messenger/analysis , Receptor, PAR-1 , Spinal Cord/physiopathology , Superoxide Dismutase/genetics , Thrombin/metabolism
17.
J Am Coll Cardiol ; 36(2): 404-9, 2000 Aug.
Article En | MEDLINE | ID: mdl-10933349

OBJECTIVES: We sought to make a prospective comparison of systematic stenting with provisional stenting guided by Doppler measurements of coronary velocity reserve and quantitative coronary angiography. BACKGROUND: Despite the increasing use of stents during percutaneous transluminal coronary angioplasty, it is unclear whether systematic stenting is superior to a strategy of provisional stenting in which stents are placed only in patients with unsatisfactory results or as a bail-out procedure. METHODS: Two hundred fifty-one patients undergoing elective coronary angioplasty were randomly assigned either to provisional stenting (group 1, in which stenting was performed if postangioplasty coronary velocity reserve was <2.2 and/or residual stenosis > or =35% or as bail-out) or to systematic stenting (group 2). The primary end point was the six-month angiographic minimal lumen diameter (MLD). Major adverse cardiac events were secondary end points (death, acute myocardial infarction and target lesion revascularization). RESULTS: Stenting was performed in 48.4% of patients in group 1 and 100% of patients in group 2 (p<0.01). Six months after angioplasty, the MLD did not differ between groups (1.90+/-0.79 mm vs. 1.99+/-0.70 mm, p = 0.39), as was the rate of binary restenosis (27.1% vs. 21.4%, p = 0.37). Among patients with restenosis, 13/32 (40.6%) in group 1 but 100% (25/25) in group 2 had in-stent restenosis (p<0.01). Target lesion revascularization (15.1% vs. 14.4% in groups 1 and 2 respectively, p = 0.89) and major adverse cardiac events (15.1% vs. 16.0%, p = 0.85) were not significantly different. CONCLUSIONS: Systematic stenting does not provide superior angiographic results at six months as compared with provisional stenting.


Angioplasty, Balloon, Coronary , Coronary Disease/therapy , Stents , Aged , Coronary Angiography , Coronary Vessels/pathology , Echocardiography, Doppler , Humans , Middle Aged , Prospective Studies
18.
Spine (Phila Pa 1976) ; 25(14): 1765-70, 2000 Jul 15.
Article En | MEDLINE | ID: mdl-10888943

STUDY DESIGN: Prospective, randomized experimental study in mice. STUDY OBJECTIVE: To determine whether insulin-like growth factor binding proteins (IGFBPs) are present in mouse spinal cord and, if so, what role they play in its development. SUMMARY OF BACKGROUND DATA: Insulin-like growth factors are well recognized hormonal effectors of growth hormone and are expressed in the mammalian spinal cord. The IGFBPs are a group of six genetically distinct proteins that bind IGFs and modulate their bioactivity. They appear in the brain during development, localize to the neuromuscular junction, and promote motor neuron survival. The benefit of IGF-I in amyotrophic lateral sclerosis ALS and its potential use in preventing motor neuron apoptosis in spinal cord injury dictates that studies of the presence and response of IGFBPs in that tissue be performed. METHODS: The IGFBPs in mouse spinal cord were analyzed by Western ligand blot, Western immunoblot, and reverse transcription-polymerase chain reaction at various time points from embryonic day 14 to postnatal day 30. RESULTS: Three IGFBPs with molecular masses of 24, 28, and 32 kDa were found, the latter two being the most prominent. The data indicate that these are IGFBP-4, -5, and -2. CONCLUSION: Both IGFBP-2 and BP-5 are developmentally regulated in mouse spinal cord, with higher levels of those at early embryonic stages indicating their potential role in development of the mouse spinal cord.


Gene Expression Regulation, Developmental , Insulin-Like Growth Factor Binding Protein 2/genetics , Insulin-Like Growth Factor Binding Protein 5/genetics , Spinal Cord/embryology , Spinal Cord/growth & development , Animals , Animals, Newborn/metabolism , Blotting, Western , DNA Primers/chemistry , Embryo, Mammalian/metabolism , Embryonic and Fetal Development , Insulin-Like Growth Factor Binding Protein 2/metabolism , Insulin-Like Growth Factor Binding Protein 5/metabolism , Ligands , Mice , Mice, Inbred BALB C , RNA, Messenger/biosynthesis , Reverse Transcriptase Polymerase Chain Reaction , Spinal Cord/metabolism
19.
Clin Plast Surg ; 27(2): 193-8, 2000 Apr.
Article En | MEDLINE | ID: mdl-10812519

Lasers are powerful tools in the treatment of benign pigmented lesions. Their role in the treatment of pigmented lesions other than those which are benign has not been defined. As with other ablative treatments, avoidance of lesions with malignant potential is essential. The wise adage First do no harm applies. By presenting the patient with a realistic goal and expectations, as well as discussing alternatives, limitations and risks, an informed decision for laser treatment can be made. Care and conservatism protect both the patient and the integrity of the laser surgeon.


Guidelines as Topic , Laser Therapy/methods , Pigmentation Disorders/surgery , Humans , Physician-Patient Relations
20.
Neurochem Int ; 37(4): 337-49, 2000 Oct.
Article En | MEDLINE | ID: mdl-10825574

Coagulation Factor XIII (F. VIII), a member of the transglutaminase (TGase) superfamily, is activated by thrombin, cross-links fibrin and stabilizes clots. Another member of this family, tissue TGase (tTG), having similar enzymatic activity, is implicated in neural development and synapse stabilization. Our previous studies indicated that synapse formation and maintenance at the neuromuscular junction (NMJ) involved components of the coagulation cascade in development. Others then showed that either F. XIII or tTG were localized at NMJs in a developmentally-regulated fashion. In the current studies, we addressed the temporal course of skeletal muscle tTG gene expression and found maximal expression at birth and continuing into the immediate postnatal period. Subcellular fractionation revealed a relatively constant particulate isoform of TGase activity which predominated in early embryonic muscle development. In contrast, cytosolic TGase specific activity became the major isoform in the postnatal period. The timing of muscle TGase activity correlated well with expression of tTG mRNA and we now present novel data of Tgm 2 gene expression for tTG in skeletal muscle. Confirming and extending the previous studies, TGase becomes localized at NMJs in the early, further ramifying in the late, neonatal period. These data suggest that the early pulse of particulate activity could coincide with the period of myoblast cell death in embryonic muscle. On the other hand, the peak cytosolic TGase activity occurs in the neonatal period, correlating temporally with muscle prothrombin expression during activity-dependent synapse elimination and possibly the source of the enzyme localized to the NMJ extracellular matrix resulting in synaptic stabilization.


Gene Expression Regulation, Enzymologic , Isoenzymes/genetics , Neuromuscular Junction/enzymology , Neuromuscular Junction/growth & development , Transglutaminases/genetics , Aging , Animals , Culture Techniques , Cytosol/enzymology , Female , Immunohistochemistry , Mice , Mice, Inbred BALB C , Molecular Weight , Muscle, Skeletal/enzymology , Neuromuscular Junction/embryology , Pregnancy , RNA, Messenger/analysis , Reverse Transcriptase Polymerase Chain Reaction , Sequence Analysis, DNA , Transglutaminases/analysis
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