Showing papers by "Kapil D. Sethi published in 2003"
Indiana University1, Cincinnati Children's Hospital Medical Center2, University of Rochester3, University of California, San Diego4, Veterans Health Administration5, University of Iowa6, University of Miami7, Creighton University8, University of Alberta9, University of Minnesota10, Columbia University11, Baylor College of Medicine12, University Health Network13, Albany Medical College14, Texas A&M University15, Wake Forest University16, North Shore-LIJ Health System17, University of Chicago18, Medical College of Wisconsin19, LSU Health Sciences Center New Orleans20, St. Joseph's Hospital and Medical Center21, Yeshiva University22, University of Colorado Denver23, University of New Mexico24, Washington University in St. Louis25, Harvard University26, University of Cincinnati27, University of Texas Southwestern Medical Center28, University of Western Ontario29, Georgia Regents University30, University of Alabama at Birmingham31, Icahn School of Medicine at Mount Sinai32, Northwestern University33, University of California, Irvine34, University of Maryland, Baltimore35, Rowan University36, Mayo Clinic37
TL;DR: Findings demonstrate consistent evidence of linkage to chromosomes 2 and X and also support the hypothesis that gene-by-gene interactions are important in PD susceptibility.
Abstract: Parkinson disease (PD) is the second most common neurodegenerative disorder. We studied 754 affected individuals, comprising 425 sibling pairs, to identify PD susceptibility genes. Screening of the parkin gene was performed in a subset of the sample having earlier age of PD onset or a positive LOD score with a marker in the parkin gene. All subjects were evaluated using a rigorous neurological assessment. Two diagnostic models were considered for genome-wide, non-parametric linkage analyses. Model I included only those individuals with a more stringent diagnosis of verified PD (216 sibling pairs) and resulted in a maximum LOD score of 3.4 on chromosome 2. Model II included all affected individuals (425 sibling pairs) and yielded a LOD score of 3.1 on the X chromosome. Our large sample was then employed to test for gene-by-gene (epistatic) interactions. A genome screen using the 23 families with PD patients having a mutation in only one allele of the parkin gene detected evidence of linkage to chromosome 10 (LOD=2.3). The 85 families with a very strong family history of PD were employed in a genome screen and, in addition to strong evidence of linkage to chromosome 2 (LOD = 4.9), also produced a LOD of 2.4 on chromosome 14. A genome screen performed in the 277 families without a strong family history of PD detected linkage to chromosomes 10 (LOD = 2.4) and X (LOD = 3.2). These findings demonstrate consistent evidence of linkage to chromosomes 2 and X and also support the hypothesis that gene-by-gene interactions are important in PD susceptibility.
148 citations
TL;DR: The use of medication and/or surgery can provide adequate tremor control in the majority of the patients and deep brain stimulation of the thalamus is the procedure of choice to avoid adverse effects seen with bilateral ablative procedures.
Abstract: Essential tremor can cause significant functional disability in some patients. The arms are the most common body part affected and cause the most functional disability. The treatment of essential tremor includes medications, surgical options and other forms of therapy. Presently there is no cure for essential tremor nor are there any medications that can slow the progression of tremor. Treatment for essential tremor is recommended if the tremor causes functional disability. If the tremor is disabling only during periods of stress and anxiety, propranolol and benzodiazepines can be used during those periods when the tremor causes functional disability. The currently available medications can improve tremor in approximately 50% of the patients. If the tremor is disabling, treatment should be initiated with either primidone or propranolol. If either primidone or propranolol do not provide adequate control of the tremor, then the medications can be used in combination. If patients experience adverse effects with propranolol, occasionally other β-adrenoceptor antagonists (such as atenolol or metoprolol) can be used. If primidone and propranolol do not provide adequate control of tremor, occasionally the use of benzodiazepines (such as clonazepam) can provide benefit. Other medications that may be helpful include gabapentin or topiramate. If a patient has disabling head or voice tremor, botulinum toxin injections into the muscles may provide relief from the tremor. Botulinum toxin in the hand muscles for hand tremor can result in bothersome hand weakness and is not widely used. There are other medications that have been tried in essential tremor and have questionable efficacy. These drugs include carbonic anhydrase inhibitors (e.g. methazolamide), phenobarbital, calcium channel antagonists (e.g. nimodipine), isoniazid, clonidine, clozapine and mirtazapine. If the patient still has disabling tremor after medication trials, surgical options are usually considered. Surgical options include thalamotomy and deep brain stimulation of the thalamus. These surgical options provide adequate tremor control in approximately 90% of the patients. Surgical morbidity and mortality for these procedures is low. Deep brain stimulation and thalamotomy have been shown to have comparable efficacy but fewer complications have been reported with deep brain stimulation. In patients undergoing bilateral procedures deep brain stimulation of the thalamus is the procedure of choice to avoid adverse effects seen with bilateral ablative procedures. The use of medication and/or surgery can provide adequate tremor control in the majority of the patients.
101 citations
TL;DR: Assessment of the clinical features suggests that an accuracy of 90% may be the highest that can be expected using current diagnostic criteria for Parkinson disease.
Abstract: Parkinson disease is a slowly progressive neurodegenerative disorder with a varied clinical picture and a variable rate of progression. Recently, there have been some studies conducted to assess the diagnostic accuracy and other clinical aspects of the disease. In the absence of a biomarker the clinical diagnosis is imprecise. This leads to a significant number of misdiagnoses, especially in early disease. Assessment of the clinical features suggests that an accuracy of 90% may be the highest that can be expected using current diagnostic criteria. In addition to bradykinesia, which is a core symptom, different types of tremors occur. Whereas the rest tremor is characteristic, action tremor, re-emergent tremor and orthostatic tremor may occur in Parkinson disease. Symptomatic treatments are quite effective in early disease but clinical course is complicated by the appearance of motor fluctuations and dyskinesias in more advanced disease. Non-motor complications, such as cognitive, psychiatric and autonomic problems, become bothersome and disabling in some patients.
48 citations
TL;DR: A 65-year-old dextral woman with hypertension presented with a 5-day history of difficulty writing with impaired adduction of her left eye and micrographia and MRI demonstrated an acute to subacute lacunar infarct involving predominantly the left red nucleus.
Abstract: A 65-year-old dextral woman with hypertension presented with a 5-day history of difficulty writing. On examination, she had impaired adduction of her left eye and micrographia. MRI demonstrated an acute to subacute lacunar infarct involving predominantly the left red nucleus …
18 citations
TL;DR: Three PD patients with dizziness due to benign paroxysmal positional vertigo (BPPV) are presented with blank facies, moderate to severe neck rigidity, as well as appendicular rigidity.
Abstract: Dizziness in patients with Parkinson’s disease (PD) is commonly ascribed to orthostatic hypotension,1 yet the true incidence of other etiologies is not known. We present three PD patients with dizziness due to benign paroxysmal positional vertigo (BPPV).
A 58-year-old man with a 6-year history of PD was being treated with carbidopa/levodopa 25/100, 1 tablet four times per day. He had a spinning sensation provoked by turning his head and at times by standing, for which he had been prescribed fludrocortisone 0.1 mg daily for suspected orthostatic hypotension. He discontinued the medication because it was not effective. Examination revealed blank facies, moderate to severe neck rigidity, as well as appendicular rigidity. His blood pressure while supine was 130/70 mm Hg with a pulse of 80 beats/min and while standing 120/66 mm Hg with a pulse of 88 beats/min.
Eye movements were unremarkable. The Dix–Hallpike …
8 citations