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Y Zoldan

Publications and source records attributed to Y Zoldan.

6 recordsLinked to original sources

Diagnosis of "non-organic" limb paresis by a novel objective motor assessment: the quantitative Hoover's test.

The differentiation of "non-organic" limb weakness from genuine paralysis is sometimes difficult in neurological practice. To address this problem, we developed a computerized quantitative method, based on the Hoover's test principle, that determines the extent of involuntary limb activation when contralateral movement is performed. Measurements of hip or arm extension isometric force are performed during direct maximal voluntary effort and during contralateral hip flexion. Maximal involuntary/voluntary force ratio (IVVR) is calculated. IVVR of the lower limbs in ten healthy subjects was 0.614, 0.044 (mean, SEM). Similar results were obtained from seven patients with genuine weakness and in the non-affected limbs of nine patients with "non-organic" mono- or hemiparesis. In contrast, IVVR in the affected limbs in the "non-organic" group was markedly increased (2.48, 0.61; P < 0.001). The same pattern was elicited in the upper limbs (2.27, 0.46 vs 0.406, 0.06; P < 0,001). We conclude that Hoover's sign in "nonorganic" paralysis is a preservation or increase of a normal synkinetic phenomenon. Quantitative measurement of the IVVR can serve as a useful ancillary test in diagnosing non-organic weakness in either lower or upper limbs.

Adult↗

Detection and measurement of an endogenous clonidine-displacing substance in human cerebrospinal fluid.

Clonidine-displacing substance (CDS) is a novel endogenous ligand for clonidine receptors previously detected in bovine brain and human serum. We examined for the first time whether CDS can be detected and measured in human cerebrospinal fluid (CSF). Using the [3H]clonidine displacement assay, we found that CDS could be identified and quantified in each of the CSF samples obtained from 81 patients with various neurological disorders. Mean level of CDS in CSF was 4.66 units/ml. Exceedingly high levels were observed in the CSF of patients with neoplastic meningitis (mean, 36.75 units/ml) and stroke (mean, 19.5 units/ml) (P < 0.0001). No correlation was found between CDS levels in CSF and age, gender, CSF protein or number of cells. CDS levels in CSF were higher than those in the serum (P < 0.01). We conclude that CDS is present and can be measured in human CSF. High CDS levels in CSF from patients with leptomeningeal metastases may serve as a tumor marker for malignant infiltration of the meninges. Additional studies in stroke patients will determine whether this endogenous ligand plays a role in the pathogenesis of cerebral ischemia.

Adolescent↗

Primary progressive freezing gait.

Freezing gait is an incapacitating symptom often observed in patients with Parkinson's disease. It has been less frequently described in association with multi-infarct state, multisystem atrophies, and normotensive hydrocephalus. In our movement disorder clinic, we have diagnosed (and followed up to 3 years; median, 16 months), 18 patients in whom progressive freezing gait was the sole neurological dysfunction. These 15 men and 3 women (aged 60-82 years; 74 +/- 6) were subjected to an extensive neurological workup that included clinical evaluation, videotaping for grading of gait disability, comprehensive blood and cerebrospinal fluid (CSF) analysis, and brain computed tomography (CT) and magnetic resonance imaging (MRI). Mean disease duration was 2.5 +/- 1.9 years (range, 0.5-6). Neurological examination disclosed freezing gait, often associated with varying degrees of postural instability. The degree of freezing gait ranged from sudden motor blocks only when confronted with obstacles to severe disability with total inability to start walking requiring a walker, massive assistance, or a wheelchair. However, patients could mimic gait movements with absolutely no freezing when seated or lying prone, and most of them could overcome arrests by the "walking-over-lines" maneuver. Otherwise, neurological examination was normal with no signs of bradykinesia, rigidity, or tremor. Blood chemistry and CSF analysis were normal. Brain CT and MRI were normal or showed mild cortical atrophy in 12 and putative lacunes in 6 patients. Therapy with levodopa or dopamine agonists was ineffective. During the follow-up period, a gradual progression of the freezing gait was observed. However, it remained unaccompanied by any other neurological findings.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

Tardive dyskinesia induced by sulpiride.

Although tardive dyskinesia is a known adverse reaction of sustained treatment with traditional neuroleptic agents, it was only rarely reported in association with sulpiride, a selective D2-receptor antagonist. We describe six patients who developed tardive dyskinesia after treatment with sulpiride for depression or gastrointestinal symptoms. In three patients, involuntary movements emerged during the course of treatment and in the others only after discontinuation of the drug. These cases indicate that sulpiride can cause tardive dyskinesia and that this drug should be administered with caution.

Aged↗