Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 201
Filter
1.
QJM ; 111(10): 699-706, 2018 Oct 01.
Article in English | MEDLINE | ID: mdl-30016528

ABSTRACT

BACKGROUND: The pattern of alcohol and substance use is changing, with the introduction of novel psychoactive substances, the internet as a means of acquisition and variations in drug purity and price. Alcohol and substance use among adolescents is associated with behavioural, mental health, health and social difficulties; arising at a vulnerable period in their development. Little is known about adolescent substance use in the UK, especially in rural areas. AIM: To investigate the prevalence of substance use amongst young people, aged 16-21 years, in Norfolk schools. DESIGN: Cross sectional questionnaire survey. METHOD: Pupils from two, sixth form colleges in Norfolk answered a self-report questionnaire designed to measure prevalence, age of onset and frequency of use for alcohol, tobacco, illicit substances including new psychoactive substances as well as demographic data. RESULTS: A total of 482 students completed the survey (68% participation rate). Life-time use of alcohol was reported by 442 (91.7%) students and over half the pupils had tried tobacco (52.5%, n=253). About 40.7% reported cannabis use and nearly one-fifth (18.9%, n=91) reported using 3,4-methylenedioxymethamphetamine (MDMA); 41.1% (n=198) students reported using 'any drug' and 23.2% (n=112) 'using an illicit drug other than cannabis' and 8.7% (n=42) reported the use of a novel psychoactive substance. CONCLUSION: The most widely used substances were alcohol, tobaccos and cannabis; in keeping with European trends. Over the past decade a decline in alcohol and drug use by adolescents has been seen in the UK. However, since 2010 this decline has slowed with an increase in substance use noted in the past 2 years. This study provides evidence to support this trend. The findings demonstrate differences between the use of substances by pupils in this Norfolk sample compared to national surveys and more urbanized areas. These regional differences can be used to assist the development of local interventions targeting substance use among adolescents.


Subject(s)
Students/statistics & numerical data , Substance-Related Disorders/classification , Substance-Related Disorders/epidemiology , Adolescent , Age Distribution , Cross-Sectional Studies , Female , Humans , Logistic Models , Male , Multivariate Analysis , Schools , Self Report , Sex Distribution , United Kingdom/epidemiology , Young Adult
2.
QJM ; 109(6): 405-9, 2016 Jun.
Article in English | MEDLINE | ID: mdl-26412803

ABSTRACT

BACKGROUND: Alcohol and substance use in adolescence can be associated with a range of health, emotional, social, behavioural and legal problems. There has been a change in the recreational drugs available to users in recent years; however, little is known about how this impacts the youngest and most vulnerable population of substance users. AIM: To investigate the prevalence of substance use among children aged 15-18 years in London schools. DESIGN: Questionnaire survey. METHOD: Students aged 15-18 years in three London schools self-completed the questionnaire which collected demographic data (age, gender and ethnicity) and data on frequency of use of alcohol, tobacco and classical recreational drugs and novel psychoactive substances. RESULTS: Completed surveys were available from 533 students (47.8% of those invited to participate). One hundred thirteen (20.4%) students reported lifetime use of at least one recreational drug, cannabis (96, 18.7%) was commonly reported and only 6 (1.1%) reported use of a novel psychoactive substance. A total of 250 (47.8%) reported using alcohol at least once; those from White and Mixed ethnic groups were more likely to report using alcohol than those in other ethnic groups. A total of 382 (74.2%) students reported using tobacco at least once, and students from ethnic minorities were more likely to smoke than their White counterparts. CONCLUSION: This study supports previous findings that alcohol and drug use are declining in adolescents in UK. There are different patterns of substance use amongst different ethnic groups; this is important to schools and policymakers planning interventions related to substance use in school-aged children.


Subject(s)
Adolescent Behavior/psychology , Alcohol Drinking/epidemiology , School Health Services , Schools , Students/statistics & numerical data , Substance-Related Disorders/epidemiology , Adolescent , Adolescent Behavior/ethnology , Alcohol Drinking/prevention & control , Cross-Sectional Studies , Ethnicity , Female , Health Knowledge, Attitudes, Practice , Humans , London/epidemiology , Male , Policy Making , Socioeconomic Factors , Substance-Related Disorders/prevention & control
4.
Am J Med Genet B Neuropsychiatr Genet ; 150B(3): 425-9, 2009 Apr 05.
Article in English | MEDLINE | ID: mdl-18712713

ABSTRACT

The instability of the CAG repeat size of the HD gene when transmitted intergenerationally has critical implications for genetic counseling practices. In particular, CAG repeats between 27 and 35 have been the subject of debate based on small samples. To address this issue, we analyzed allelic instability in the Venezuelan HD kindreds, the largest and most informative families ascertained for HD. We identified 647 transmissions. Our results indicate that repeats in the 27-35 CAG range are highly stable. Out of 69 transmitted alleles in this range, none expand into any penetrant ranges. Contrastingly, 14% of alleles transmitted from the incompletely penetrant range (36-39 CAGs) expand into the completely penetrant range, characterized by alleles with 40 or more CAG repeats. At least 12 of the 534 transmissions from the completely penetrant range contract into the incompletely penetrant range of 36-39 CAG repeats. In these kindreds, none of the individuals with 27-39 CAGs were symptomatic, even though they ranged in age from 11 to 82 years. We expect these findings to be helpful in updating genetic counseling practices.


Subject(s)
Family , Genetic Counseling , Huntington Disease/genetics , Trinucleotide Repeat Expansion , Adolescent , Adult , Age of Onset , Aged , Aged, 80 and over , Alleles , Child , Female , Humans , Huntingtin Protein , Male , Middle Aged , Nerve Tissue Proteins/genetics , Nuclear Proteins/genetics , Penetrance , Venezuela , Young Adult
5.
J Feline Med Surg ; 6(4): 259-69, 2004 Aug.
Article in English | MEDLINE | ID: mdl-15265481

ABSTRACT

The three calcitropic hormones, parathyroid hormone (PTH), 1,25-dihydroxycholecalciferol and calcitonin are together responsible for calcium homeostasis in the mammal. Feline PTH is an 84 amino acid, single chain polypeptide with a molecular weight of 9449, which is secreted by the parathyroid glands. The principle secretagogue for PTH is a low plasma ionised calcium concentration, although both 1,25-dihydroxycholecalciferol and phosphate have significant roles in regulating PTH secretion. The ability to accurately measure circulating PTH in the cat has simplified the evaluation of disorders of calcium metabolism in this species. In primary parathyroid disorders the lesion is located within the parathyroid gland, with parathyroid secretion being inappropriate to the prevailing mineral balance. By contrast, in secondary conditions a pathological state out with the parathyroid gland alters mineral homeostasis and the parathyroid gland responds in an appropriate manner. The measurement of circulating PTH may then be used to determine if PTH secretion is appropriate to the prevailing calcium concentrations to differentiate primary from secondary disorders. Although primary hyper and hypoparathyroidism are generally considered rare endocrine conditions of the cat, the ability to measure PTH has led to their increasing recognition.


Subject(s)
Cat Diseases/physiopathology , Parathyroid Diseases/veterinary , Animals , Cats , Parathyroid Diseases/physiopathology
6.
J Chem Neuroanat ; 27(3): 143-64, 2004 Jun.
Article in English | MEDLINE | ID: mdl-15183201

ABSTRACT

Prior studies suggest differences exist among striatal projection neuron types in their vulnerability to Huntington's disease (HD). In the present study, we immunolabeled the fibers and terminals of the four main types of striatal projection neuron in their target areas for substance P, enkephalin, or glutamic acid decarboxylase (GAD), and used computer-assisted image analysis to quantify the abundance of immunolabeled terminals in a large sample of HD cases ranging from grade 0 to grade 4 [J. Neuropathol. Exp. Neurol. 44 (1985) 559], normalized to labeling in control human brains. Our goal was to characterize the relative rates of loss of the two striatopallidal projection systems (to the internal versus the external pallidal segments) and the two striatonigral projections systems (to pars compacta versus pars reticulata). The findings for GAD and the two neuropeptides were similar--the striatal projection to the external pallidal segment was the most vulnerable, showing substantial loss by grade 1. Loss of fibers in both subdivisions of the substantia nigra was also already great by grade 1. By contrast, the loss in the striatal projection system to the internal segment of globus pallidus proceeded more gradually. By grade 4 of HD, however, profound loss in all projection systems was apparent. These findings support the notion that the striatal neurons preferentially projecting to the internal pallidal segment are, in fact, less vulnerable in HD than are the other striatal projection neuron types.


Subject(s)
Corpus Striatum/pathology , Huntington Disease/pathology , Neural Pathways/pathology , Neurons/pathology , Adolescent , Adult , Aged , Aged, 80 and over , Child , Female , Glutamate Decarboxylase/metabolism , Humans , Image Processing, Computer-Assisted , Immunohistochemistry , Male , Middle Aged , Substance P/metabolism
7.
J Am Vet Med Assoc ; 220(12): 1799-804, 2002 Jun 15.
Article in English | MEDLINE | ID: mdl-12092951

ABSTRACT

OBJECTIVE: To determine prevalence of systolic hypertension and associated risk factors in cats with chronic renal failure evaluated in first-opinion practice. DESIGN: Prospective study. ANIMALS: 103 cats with chronic renal failure. PROCEDURE: Systolic arterial blood pressure (SABP) was measured with a noninvasive Doppler technique, and cats that had SABP > 175 mm Hg on 2 occasions or that had SABP > 175 mm Hg and compatible ocular lesions were classified as hypertensive. Information from the history (previous treatment for hyperthyroidism, age), physical examination (sex, body weight), routine plasma biochemical analyses (creatinine, cholesterol, potassium, sodium, chloride, and calcium concentrations), and thyroid status were evaluated as potential risk factors for systolic hypertension. Variables associated with systolic hypertension were evaluated by use of logistic regression. RESULTS: 20 (19.4%; 95% confidence interval, 13 to 28%) cats had systolic hypertension. Plasma potassium concentration was significantly and inversely associated with systolic hypertension. CONCLUSIONS AND CLINICAL RELEVANCE: Prevalence of systolic hypertension, although clinically important, was lower than that reported previously. The cause of the inverse association between systolic hypertension and plasma potassium concentration is not yet known.


Subject(s)
Cat Diseases/epidemiology , Hypertension, Renal/veterinary , Kidney Failure, Chronic/veterinary , Animals , Blood Pressure , Cat Diseases/diagnosis , Cat Diseases/etiology , Cats , England/epidemiology , Female , Hypertension, Renal/epidemiology , Hypertension, Renal/etiology , Hyperthyroidism/diagnosis , Hyperthyroidism/veterinary , Kidney Failure, Chronic/complications , Kidney Failure, Chronic/diagnosis , Male , Potassium/blood , Prevalence , Prospective Studies , Regression Analysis , Risk Factors , Systole
8.
J Exp Bot ; 52(364): 2151-9, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11604454

ABSTRACT

Like most monocarpic plants, longevity of Arabidopsis thaliana plants is controlled by the reproductive structures; however, they appear to work differently from most dicots studied. Neither male- and female-sterility mutations (ms1-1 and bell1, respectively) nor surgical removal of the stems with inflorescences (bolts) at various stages significantly increased the longevity of individual rosette leaves, yet the mutants and treated plants lived 20-50 d longer, measured by the death of the last rosette and/or the last cauline leaf. A series of growth mutations (clv2-4, clv3-2, det3, vam1 enh, and dark green) also increased plant longevity by 20-30 d but did not delay the overall development of the plants. The mutations prolonged plant life through the production of new leaves and stems with inflorescences (bolts) rather than by extending leaf longevity. In growing stems, the newly-formed leaves may induce senescence in the older leaves; however, removal of the younger leaves did not significantly increase the life of the older leaves on the compressed stems of Arabidopsis. Since plants that produce more bolts also live longer, the reproductive load (dry weight) of the bolts did not seem to drive leaf or whole plant senescence here. The developing reproductive structures caused the death of the plant by preventing regeneration of leaves and bolts, which are green and presumably photosynthetic. They also exerted a correlative control (repression) on the development of additional reproductive structures.


Subject(s)
Adaptation, Physiological , Apoptosis/physiology , Arabidopsis/physiology , Arabidopsis/genetics , Cellular Senescence/physiology , Chlorophyll/metabolism , Genotype , Mutation/physiology , Plant Stems/genetics , Plant Stems/physiology , Reproduction , Signal Transduction
9.
Neurogenetics ; 3(3): 133-43, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11523564

ABSTRACT

Dystonia is a movement disorder involving sustained muscle contractions and abnormal posturing with a strong hereditary predisposition and without a distinct neuropathology. In this study the TOR1A (DYT1) gene was screened for mutations in cases of early onset dystonia and early onset parkinsonism (EOP), which frequently presents with dystonic symptoms. In a screen of 40 patients, we identified three variations, none of which occurred in EOP patients. Two infrequent intronic single base pair (bp) changes of unknown consequences were found in a dystonia patient and the mother of an EOP patient. An 18-bp deletion (Phe323_Tyr328del) in the TOR1A gene was found in a patient with early onset dystonia and myoclonic features. This deletion would remove 6 amino acids close to the carboxy terminus, including a putative phosphorylation site of torsinA. This 18-bp deletion is the first additional mutation, beyond the GAG-deletion (Glu302/303del), to be found in the TOR1A gene, and is associated with a distinct type of early onset dystonia.


Subject(s)
Carrier Proteins/genetics , Dystonia Musculorum Deformans/genetics , Molecular Chaperones , Parkinson Disease/genetics , Polymorphism, Genetic , Adolescent , Adult , Age of Onset , Child , Child, Preschool , DNA Primers , Female , Humans , Infant , Male , Middle Aged , Mutation , Pedigree , Polymerase Chain Reaction , Polymorphism, Single-Stranded Conformational , Sequence Deletion
10.
Neurology ; 56(6): 799-802, 2001 Mar 27.
Article in English | MEDLINE | ID: mdl-11274323

ABSTRACT

The authors assessed clinical outcome for up to one year after staged bilateral pallidotomy in 14 patients with advanced PD. One year after surgery, dyskinesias were virtually abolished and there were significant reductions in "off" time (67%) and activities of daily living "off" scores (24%), as well as nonsignificant reduction in "off" motor score (39%); "on" scores were unchanged. One patient developed a visual field deficit; two had transient confusion. Staged bilateral pallidotomy improves motor function in selected patients with advanced PD.


Subject(s)
Globus Pallidus/surgery , Parkinson Disease/physiopathology , Parkinson Disease/surgery , Adult , Aged , Female , Follow-Up Studies , Functional Laterality/physiology , Humans , Male , Middle Aged , Movement/physiology , Prognosis
11.
Exp Neurol ; 167(1): 196-204, 2001 Jan.
Article in English | MEDLINE | ID: mdl-11161608

ABSTRACT

Excitotoxic lesions of the striatum are mediated by the combined activity of N-methyl-d-aspartate (NMDA) receptors and metabotropic glutamate receptors (mGluRs). Intrastriatal injection of the NMDA receptor agonists NMDA or quinolinic acid creates large lesions, but in rats that have been decorticated to remove endogenous glutamatergic input, NMDA and quinolinic acid are no longer toxic. We report that NMDA toxicity can be restored in decorticated animals by coinjection of the group I mGluR agonists t-ACPD, t-ADA, or CHPG. In addition, injections of two group I mGluR antagonists, AIDA and (S)-4C3HPG, can protect against striatal lesions produced by quinolinic acid or NMDA injections in normal rats by blocking activation of group I mGluRs. The group II mGluR agonist APDC fails to protect against quinolinic acid or NMDA toxicity in intact animals or to restore NMDA toxicity in decorticated animals, suggesting that the role of group II receptors in this excitotoxic model is minimal. These observations confirm the important role of group I mGluRs in excitotoxicity and identify these receptors as promising targets for therapeutic intervention in neurodegenerative disease processes.


Subject(s)
Cerebral Decortication , Corpus Striatum/metabolism , N-Methylaspartate/toxicity , Quinolinic Acid/toxicity , Receptors, Metabotropic Glutamate/metabolism , Animals , Corpus Striatum/drug effects , Corpus Striatum/pathology , Dose-Response Relationship, Drug , Drug Antagonism , Excitatory Amino Acid Agonists/pharmacology , Excitatory Amino Acid Antagonists/pharmacology , Male , N-Methylaspartate/antagonists & inhibitors , Quinolinic Acid/antagonists & inhibitors , Rats , Rats, Sprague-Dawley , Receptors, Metabotropic Glutamate/agonists , Receptors, Metabotropic Glutamate/antagonists & inhibitors
12.
Neurology ; 56(4): 455-62, 2001 Feb 27.
Article in English | MEDLINE | ID: mdl-11222787

ABSTRACT

BACKGROUND: Preclinical studies suggest that glutamate antagonists help ameliorate motor fluctuations in patients with PD treated with levodopa. METHODS: In a multicenter, randomized, double-blind, placebo-controlled, parallel-group, dose-ranging study, the authors assessed the safety, tolerability, and efficacy of the glutamate receptor blocker remacemide hydrochloride in 279 patients with motor fluctuations treated with levodopa. The primary objective was to assess the short-term tolerability and safety of four dosage levels of remacemide during 7 weeks of treatment. Patients were also monitored with home diaries and the Unified PD Rating Scale (UPDRS) to collect preliminary data on treatment efficacy. RESULTS: Remacemide was well tolerated up to a dosage of 300 mg/d on a twice daily schedule and 600 mg/d on a four times daily schedule. The most common dosage-related adverse events were dizziness and nausea, as observed in previous studies of remacemide. The percent "on" time and motor UPDRS scores showed trends toward improvement in the patients treated with 150 and 300 mg/d remacemide compared with placebo-treated patients, although these improvements were not significant. CONCLUSION: Remacemide is a safe and tolerable adjunct to dopaminergic therapy for patients with PD and motor fluctuations. Although this study had limited power to detect therapeutic effects, the observed improvement is consistent with studies of non-human primates with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced parkinsonian signs and symptoms. Additional studies are warranted to confirm these results over an extended period of observation, and to explore the potential neuroprotective effects of remacemide in slowing the progression of PD.


Subject(s)
Acetamides/adverse effects , Acetamides/therapeutic use , Parkinson Disease/drug therapy , Aged , Double-Blind Method , Female , Humans , Male , Middle Aged , Multicenter Studies as Topic , Patient Compliance , Receptors, Glutamate
13.
Neurobiol Dis ; 8(1): 90-102, 2001 Feb.
Article in English | MEDLINE | ID: mdl-11162243

ABSTRACT

Alzheimer's disease transgenic mice overexpressing human amyloid precursor protein (hAPP) with the Swedish double mutation (hAPP(Sw)) develop age-related amyloid deposition and behavioral and electrophysiologic changes by an unknown mechanism. Analysis of glutamatergic receptor subtypes in 4- and 15-month-old heterozygous hAPP(Sw) transgenic mice revealed a selective increase in AMPA receptor binding in the hippocampus of 15-month-old transgenic mice, which have established cortical and hippocampal amyloid deposits. There were no significant alterations of GluR1, GluR2, and GluR4 protein expression by semiquantitative confocal analysis or GluR1 mRNA by in situ hybridization. There was no significant alteration in NMDA, in group I and II metabotropic glutamate and in muscarinic receptor binding, or in striatal dopamine and adenosine receptor binding in 15-month-old mice. These data suggest that mutant APP overexpression or age-related amyloid deposition produce a subtle specific alteration in hippocampal glutamate receptors with aging.


Subject(s)
Amyloid beta-Protein Precursor/metabolism , Hippocampus/metabolism , Receptors, Glutamate/metabolism , Amyloid beta-Protein Precursor/genetics , Animals , Autoradiography , Cholinesterases/metabolism , Hippocampus/enzymology , Humans , In Situ Hybridization , Mice , Mice, Inbred C57BL , Mice, Transgenic , Mutation , Receptors, AMPA/genetics , Receptors, AMPA/metabolism , Receptors, Dopamine/metabolism , Receptors, Glutamate/genetics , Receptors, Metabotropic Glutamate/genetics , Receptors, Metabotropic Glutamate/metabolism , Receptors, Muscarinic/genetics , Receptors, Muscarinic/metabolism , Receptors, N-Methyl-D-Aspartate/genetics , Receptors, N-Methyl-D-Aspartate/metabolism , Receptors, Purinergic P1/metabolism
14.
Am J Cardiol ; 85(3): 294-8, 2000 Feb 01.
Article in English | MEDLINE | ID: mdl-11078295

ABSTRACT

In acute myocardial infarction (AMI), immediate beta-blocker therapy reduces the incidence of reinfarction and recurrent chest pain in patients receiving tissue plasminogen activator (t-PA). Data from the Thrombolysis in Myocardial Infarction (TIMI)-2 trial also raises the possibility that such therapy may reduce the rate of intracranial hemorrhage (ICH). We reviewed data obtained from 60,329 patients treated with t-PA who were enrolled in the National Registry of Myocardial Infarction 2. Of the 60,329 in the study cohort, 23,749 patients (39.4%) were treated with immediate beta-blocker therapy and 542 patients (0.9%) developed an ICH. In a multivariate model that included all covariates known to be associated with the development of ICH, immediate beta-blocker therapy was associated with a 31% reduction in the ICH rate (odds ratio 0.69, 95% confidence intervals 0.57 to 0.84). Thus, in the present study, the use of immediate beta-blocker therapy in patients with AMI treated with t-PA was associated with a significant reduction in ICH. This finding supports the observations made in the TIMI 2 trial and serves to reinforce the recommendations made by the American College of Cardiology/American Heart Association task force that immediate beta-blocker therapy should be administered to all patients with AMI who do not have contraindications to this therapy.


Subject(s)
Adrenergic beta-Antagonists/therapeutic use , Intracranial Hemorrhages/prevention & control , Myocardial Infarction/drug therapy , Plasminogen Activators/adverse effects , Thrombolytic Therapy , Tissue Plasminogen Activator/adverse effects , Aged , California , Cohort Studies , Female , Humans , Intracranial Hemorrhages/drug therapy , Male , Massachusetts , Michigan , Registries , Retrospective Studies
15.
J Comp Neurol ; 421(2): 247-55, 2000 May 29.
Article in English | MEDLINE | ID: mdl-10813785

ABSTRACT

The potential role for dopamine in the subthalamic nucleus was investigated in human postmortem tissue sections by examining; (1) immunostaining for tyrosine hydroxylase, the rate-limiting enzyme in catecholamine synthesis; (2) binding of [(3)H]-SCH23390 (D1-like), [(3)H]-YM-09151-2 (D2-like), and [(3)H]-mazindol (dopamine uptake); and (3) expression of dopamine D1 and D2 receptor mRNAs. Immunostaining for tyrosine hydroxylase was visualized in Bouin's-fixed tissue by using a monoclonal antibody and the avidin-biotin-complex method. The cellular localization of the dopamine D1 and D2 receptor mRNAs was visualized by using a cocktail of human specific oligonucleotide probes radiolabeled with (35)S-dATP. Inspection of immunostained tissue revealed a fine network of tyrosine hydroxylase-immunostained fibers traversing the nucleus; no immunopositive cells were detected. Examination of emulsion-coated tissue sections processed for D1 and D2 receptor mRNA revealed, as expected, an abundance of D1 and D2 mRNA-positive cells in the caudate nucleus and putamen. However, no D1 or D2 receptor mRNA-expressing cells were detected in the subthalamic nucleus. Further, semiquantitative analysis of D1-like, D2-like and dopamine uptake ligand binding similarly revealed an enrichment of specific binding in the caudate nucleus and putamen but not within the subthalamic nucleus. However, a weak, albeit specific, signal for [(3)H]-SCH23390 and [(3)H]-mazindol was detected in the subthalamic nucleus, suggesting that the human subthalamic nucleus may receive a weak dopaminergic input. As weak D1-like binding is detected in the subthalamic nucleus, and subthalamic neurons do not express dopamine D1 or D2 receptor mRNAs, together these data suggest that the effects of dopaminergic agents on the activity of human subthalamic neurons may be indirect and mediated via interaction with dopamine D1-like receptors.


Subject(s)
Dopamine/metabolism , Receptors, Dopamine D1/metabolism , Receptors, Dopamine D2/metabolism , Subthalamic Nucleus/metabolism , Benzamides/metabolism , Benzazepines/metabolism , Biomarkers , Dopamine Antagonists/metabolism , Dopamine Uptake Inhibitors/metabolism , Humans , Mazindol/metabolism , Parkinson Disease/metabolism , RNA, Messenger/metabolism , Tyrosine 3-Monooxygenase/metabolism
16.
J Comp Neurol ; 419(4): 407-21, 2000 Apr 17.
Article in English | MEDLINE | ID: mdl-10742712

ABSTRACT

N-methyl-D-aspartate (NMDA) receptors are composed of subunits from two families: NR1 and NR2. We used a dual-label in situ hybridization technique to assess the levels of NR1 and NR2A-D messenger ribonucleic acid (mRNA) expressed in projection neurons and interneurons of the human striatum. The neuronal populations were identified with digoxigenin-tagged complementary RNA probes for preproenkephalin (ENK) and substance P (SP) targeted to striatal projection neurons, and somatostatin (SOM), glutamic acid decarboxylase 67 kD (GAD(67)), and choline acetyltransferase (ChAT) targeted to striatal interneurons. Intense NR1 signals were found over all striatal neurons. NR2A signals were high over GAD(67)-positive neurons and intermediate over SP-positive neurons. ENK-positive neurons displayed low NR2A signals, whereas ChAT- and SOM-positive neurons were unlabeled. NR2B signals were intense over all neuronal populations in striatum. Signals for NR2C and NR2D were weak. Only ChAT-positive neurons displayed moderate signals, whereas all other interneurons and projection neurons were unlabeled. Moderate amounts of NR2D signal were detected over SOM- and ChAT-positive neurons; GAD(67)- and SP-positive striatal neurons displayed low and ENK-positive neurons displayed no NR2D hybridization signal. These data suggest that all human striatal neurons have NMDA receptors, but different populations have different subunit compositions that may affect function as well as selective vulnerability.


Subject(s)
Neostriatum/metabolism , Neural Pathways/metabolism , Neurons/metabolism , RNA, Messenger/metabolism , Receptors, N-Methyl-D-Aspartate/genetics , Receptors, N-Methyl-D-Aspartate/metabolism , Aged , Choline O-Acetyltransferase/genetics , Enkephalins/genetics , Female , Glutamate Decarboxylase/genetics , Humans , In Situ Hybridization , Male , Middle Aged , Neostriatum/cytology , Neural Pathways/cytology , Neurons/cytology , Protein Precursors/genetics , Tachykinins/genetics
17.
J Neurosurg ; 92(3): 375-83, 2000 Mar.
Article in English | MEDLINE | ID: mdl-10701522

ABSTRACT

OBJECT: Pallidotomy for the treatment of medically refractory Parkinson's disease (PD) has enjoyed renewed popularity. However, the optimal surgical technique, lesion location, and long-term effectiveness of pallidotomy remain subjects of debate. In this article the authors describe their surgical technique for performing pallidotomy without using microelectrode guidance, and the clinical and radiological results of this procedure. METHODS: Patients were evaluated preoperatively by using a battery of validated clinical rating scales and magnetic resonance (MR) imaging of the brain. Individuals with severe treatment-refractory idiopathic PD who were believed to be good candidates for surgery underwent computerized tomography scanning- and MR imaging-guided stereotactic pallidotomy. Intraoperative macrostimulation was used to optimize lesion placement and to avoid injury to nearby structures. Lesion location and size were calculated from MR imaging sequences of the brain obtained within the first 24 hours after surgery and again 3 months later. Clinical examinations were conducted at 1.5, 3, 6, 12, and 24 months after surgery. Seventy-five patients (mean age 61 years, range 38-79 years) underwent unilateral pallidotomy. Significant improvements were observed in the "off' period scores for the activities of daily living portion of the Unified Parkinson's Disease Rating Scale (UPDRS), the UPDRS motor scores, total "on" time, levodopa-induced dyskinesias, and contralateral tremor. These improvements were maintained 24 months postoperatively. The mean lesion volume measured on the immediate postoperative MR image was 73 +/- 5.4 mm3. Radiological analysis suggests that initial lesion volume does not predict outcome. The only permanent major complication was a single visual field defect. CONCLUSIONS: Pallidotomy performed without using microelectrode guidance is a safe and effective treatment for selected patients with medically refractory PD.


Subject(s)
Brain Mapping/instrumentation , Globus Pallidus/surgery , Parkinson Disease/surgery , Stereotaxic Techniques/instrumentation , Adult , Aged , Female , Globus Pallidus/physiopathology , Humans , Male , Microelectrodes , Middle Aged , Monitoring, Intraoperative/instrumentation , Parkinson Disease/physiopathology , Treatment Outcome
18.
Ann Neurol ; 47(2): 201-10, 2000 Feb.
Article in English | MEDLINE | ID: mdl-10665491

ABSTRACT

Mutations in the alpha-synuclein, parkin, and ubiquitin carboxy-terminal hydrolase L1 (UCH-L1) genes have been linked to some cases of familial Parkinson's disease. To provide insight into how these genes may relate to each other and contribute to the pathology of Parkinson's disease, their expression was examined in normal human brain. Tissue sections from multiple regions of 11 normal human brains were hybridized with radiolabeled and digoxygenin-labeled cRNA probes for alpha-synuclein, parkin, and UCH-L1 mRNA. Expression of each of these three genes was predominantly neuronal. Alpha-synuclein and parkin mRNAs were expressed in a restricted number of brain regions, whereas UCH-L1 mRNA was more uniformly expressed throughout brain. The melanin-containing dopamine neurons of the substantia nigra had particularly robust expression. The expression patterns of alpha-synuclein and parkin mRNAs were similar, suggesting that these two proteins may be involved in common pathways contributing to the pathophysiology of Parkinson's disease.


Subject(s)
Brain/metabolism , Ligases , Nerve Tissue Proteins/genetics , Proteins/genetics , RNA, Messenger/metabolism , Thiolester Hydrolases/genetics , Ubiquitin-Protein Ligases , Aged , Basal Ganglia/metabolism , Dopamine/metabolism , Female , Humans , Male , Mesencephalon/metabolism , Middle Aged , Parkinson Disease/genetics , Reference Values , Synucleins , Telencephalon/metabolism , Tissue Distribution , Ubiquitin Thiolesterase , alpha-Synuclein
19.
Neurology ; 54(2): 452-8, 2000 Jan 25.
Article in English | MEDLINE | ID: mdl-10668713

ABSTRACT

OBJECTIVE: To determine the rate of functional decline in a large cohort of patients with Huntington's disease (HD) followed at 43 sites by the Huntington Study Group (HSG). METHODS: The annual rate of functional decline was measured using the Total Functional Capacity Scale (TFC) and the Independence Scale (IS) in 960 patients with definite HD followed prospectively for a mean of 18.3 months. All patients were rated with the Unified Huntington's Disease Rating Scale (UHDRS). Sample size calculations for hypothetical clinical trials were calculated. RESULTS: A factor analysis of the UHDRS at baseline yielded 15 factors accounting for 77% of the variance. The TFC score declined at a rate of 0.72 units/year (standard error [SE] 0.04) and the IS score declined at a rate of 4.52 units/year (SE 0.23). Lower TFC score at baseline, indicating more severe impairment, was associated with less rapid annual decline in TFC score, perhaps reflecting the floor effect of the scale. The annual rate of decline for 575 patients with baseline TFC scores of 7 to 13 was 0.97 (SE 0.06), was 0.38 (SE 0.08) for 270 patients with baseline TFC scores of 3 to 6, and was 0.06 (SE 0.1) for 101 patients with TFC scores of 0 to 2. In multivariate analysis (n = 960), longer disease duration and better cognitive status at baseline were associated with a less rapid rate of decline in TFC score, whereas depressive symptomatology was the only factor associated with more rapid decline on the IS score. Age at onset of HD, sex, weight, and education did not affect decline on either score. CONCLUSIONS: The comparable rates of decline on the TFC and the IS scores with other published studies suggest that these estimates of functional decline are representative of HD patients who are evaluated at HSG research sites. In longitudinal analysis, longer disease duration and better neuropsychological performance at baseline were associated with a less rapid rate of decline in TFC score, whereas depressive symptomatology at baseline was associated with a more rapid decline in the IS score. These rates of functional decline and the covariates that modify them should be considered in estimating statistical power and designing future therapeutic trials involving HD patients with early or moderately severe disease.


Subject(s)
Activities of Daily Living , Huntington Disease/diagnosis , Huntington Disease/physiopathology , Adult , Body Weight , Cohort Studies , Disability Evaluation , Disease Progression , Educational Status , Female , Humans , Male , Middle Aged , Prognosis , Prospective Studies , Psychomotor Performance , Sample Size , Severity of Illness Index , Sex Factors
20.
Ann Neurol ; 46(5): 761-9, 1999 Nov.
Article in English | MEDLINE | ID: mdl-10553994

ABSTRACT

To gain insight into the neural pathways involved in the pathogenesis of DYT1 dystonia, we have mapped the cellular expression of the mRNA encoding torsinA and the closely related family member, torsinB, in normal adult human brain. Here, we report an intense expression of torsinA mRNA in the substantia nigra pars compacta dopamine neurons, the locus ceruleus, the cerebellar dentate nucleus, Purkinje cells, the basis pontis, numerous thalamic nuclei, the pedunculopontine nucleus, the oculomotor nucleus, the hippocampal formation, and the frontal cortex. Within the caudateputamen, the cellular expression of torsinA mRNA was heterogeneous; a moderate signal was found overlying large cholinergic neurons, and most striatal neurons exhibited only a very weak signal. A moderate signal was detected in numerous midbrain and hindbrain nuclei. A weak cellular signal was detected in neurons of the globus pallidus and subthalamic nucleus. In marked contrast to torsinA, no specific mRNA signal was detected for torsinB. That torsinA mRNA is enriched in several basal ganglia nuclei, including the dopamine neurons in the substantia nigra, is intriguing since it suggests that DYT1 dystonia may be associated with a dysfunction in dopamine transmission.


Subject(s)
Brain/metabolism , Carrier Proteins/genetics , Molecular Chaperones , RNA, Messenger/genetics , Adult , Aged , Aged, 80 and over , Basal Ganglia/metabolism , Corpus Striatum/metabolism , Dentate Gyrus/metabolism , Dystonia Musculorum Deformans/genetics , Female , Frontal Lobe/metabolism , Humans , Locus Coeruleus/metabolism , Male , Middle Aged , Neurons/metabolism , Purkinje Cells/metabolism , RNA, Messenger/analysis , Rhombencephalon/metabolism , Substantia Nigra/metabolism , Thalamus/metabolism
SELECTION OF CITATIONS
SEARCH DETAIL
...