Biomedical subjects

S Mandel

Publications and source records attributed to S Mandel.

At least 55 records · Page 3Linked to original sources

PubMed1999

Diagnostic algorithms for neuromuscular diseases.

Neuromuscular disorders can impose significant disability in patients by virtue of weakness, pain, and sensory and autonomic symptoms and deficits. For all of these disorders, supportive measures, appropriate physical therapy, and respiratory support are beneficial. Pain management can be accomplished by the use of antiepileptic medications, such as carbamazepine, phenytoin, valproic, and gabapentin. Tricyclic antidepressants can also be helpful for pain management and depression. Benzodiazepines and baclofen are helpful for management of spasticity. No specific treatment exists yet for the motor neuron disorders. In peripheral neuropathies, identifying and treating the cause is most important. In other neuropathies, such as in acute or chronic inflammatory demyelinating neuropathies, immunosuppression is indicated. Myasthenia gravis can be treated with cholinesterase inhibitors and immunosuppression. A specific treatment does not exist yet for muscular dystrophies. Immunosuppression is helpful in patients with inflammatory myopathies. Toxic myopathies can be treated by removing the causative agent and by supportive measures. Endocrine myopathies will respond to treatment of the primary endocrinopathy.

Algorithms↗

PubMed1998

Synovial effusion in reflex sympathetic dystrophy: an additional sign for diagnosis and staging.

PURPOSE: To improve the present MRI criteria for diagnosis and staging of reflex sympathetic dystrophy (RSD) by including increased joint fluid as an additional MRI sign of RSD. DESIGN AND PATIENTS: One hundred and fourteen extremities (69 affected and 45 contralateral controls) in 57 consecutive patients with RSD were evaluated using a 1.5-T unit. T1- and T2-weighted pulse sequences, often with fat suppression, were used before and after administration of intravenous contrast enhancement (Gd). Following T2-weighted image digitization the volume of synovial fluid was measured with a computer model. RESULTS: Effusions were detected in 61% of the extremities suspected of RSD and in 44% of the contralateral control joints. The mean fluid quantity measured in the symptomatic articulation was 201 mm3. MRI diagnosis of RSD based on previously described criteria was done in 62% of the patients, yielding a sensitivity of 60%. Effusions were present in 79% of the false negative MRI cases. Retrospectively considering the presence of fluid as a potential positive criterion for RSD increases the sensitivity by 31% (to 91%). CONCLUSIONS: Joint effusions are probably associated with early stages of RSD. Adding effusion to the list of radiological criteria for RSD increases the sensitivity of MRI from 60% to 91%.

Adult↗

PubMed1998

Correlation analysis of somatosensory evoked potential waveforms: clinical applications.

OBJECTIVE: To assess the validity of the correlation coefficient (CC) as a diagnostic tool in evaluating somatosensory evoked potential (SEP) waveforms. DESIGN: SEP waveforms were recorded over the spine and scalp in response to tibial nerve stimulation at the ankle for 30 patients. SETTING: A general community, ambulatory, private referral center. PATIENTS: Patients were all ambulatory and were selected randomly from among existing patient records at the medical center. MAIN OUTCOME MEASURE: The test for validity uses the CC to verify reproducibility. The test for side-to-side symmetry uses the CC to obtain a measure of similarity between left and right tibial scalp responses. For both tests, a table is presented with CCs for normal subjects. If the CC for each patient falls below the appropriate critical value from the table, then the CC is taken to be abnormal; p values are provided at specific levels in this table. RESULTS: A new data base for the means and critical values of CCs with corresponding p values is established for normal subjects. Most of the patient data reveal significant CC nonreproducibility and lack of symmetry in tibial scalp SEP waveforms. CONCLUSION: The CC provides objective and quantitative waveform information that complements latency and amplitude measurements in the clinical interpretation of tibial scalp SEP waveforms.

Algorithms↗

PubMed1998

Voice range in superior laryngeal nerve paresis and paralysis.

Evaluation of Physiologic Frequency Range (PFR) and Musical Frequency Range (MRP) of Phonation was performed on 56 adults (singers and nonsingers) presenting with superior laryngeal nerve (SLN) paresis or paralysis confirmed by laryngeal electromyography. The most common etiology was neuritis (69.7%), followed by iatrogenic and unknown causes,each accounting for 10.2% of cases, and finally trauma (8.9%). Both female and male singers with SLN paresis or paralysis had significantly higher PFR and MPR than nonsingers. Female classical singers presented PFR and MPR of up to 10 semitones (ST) higher than nonclassical singers and nonsingers. The lowest PFR and musical ranges were found in patients with SLN paresis associated with recurrent laryngeal nerve paresis or paralysis. The authors suggest that voice range measurement is a useful parameter for analyzing the effects of SLN paresis or paralysis on voice and that it may also assist in measuring outcome following voice therapy.

Adult↗

PubMed1998

Increased soft-tissue blood flow in patients with reflex sympathetic dystrophy of the lower extremity revealed by power Doppler sonography.

OBJECTIVE: We evaluated the ability of power Doppler sonography to show increased soft-tissue blood flow in patients with reflex sympathetic dystrophy of the lower extremity. SUBJECTS AND METHODS: Power Doppler sonography was performed in 30 patients with reflex sympathetic dystrophy of the lower extremity and in 26 asymptomatic control subjects. The bilateral power Doppler sonograms that were obtained of the soft tissues of the dorsum of the foot of each subject were grouped in pairs, and three sonologists who were unaware of clinical information independently reviewed the images. Images were evaluated for the amount of power Doppler signal shown on the following scale: 1 = no flow or minimal flow; 2 = mild flow; 3 = moderate flow; and 4 = marked flow. RESULTS: More power Doppler flow was seen in the patients with reflex sympathetic dystrophy than in the control subjects (p < .005). In addition, side-to-side asymmetry of flow was seen in patients, but this trend was not statistically significant (p < .20). Receiver operating characteristic (ROC) analysis showed that combined flow and asymmetry were more related to reflex sympathetic dystrophy than either parameter alone (area under the ROC curve: for flow, 0.748; for asymmetry, 0.566; for both, 0.799). We found that when the sum of power Doppler flow in both feet was greater than or equal to five, and asymmetry of flow was greater than or equal to one, the sensitivity of power Doppler sonography for reflex sympathetic dystrophy was 73% and the specificity was 92%. CONCLUSION: Patients with reflex sympathetic dystrophy of the lower extremity have increased power Doppler flow compared with asymptomatic control subjects. Patients may also exhibit more side-to-side asymmetry of flow than control subjects.

Adolescent↗

PubMed1996

Superior laryngeal nerve paresis and paralysis.

Superior laryngeal nerve paresis and paralysis are relatively common but often difficult to diagnose with certainty. They are most commonly caused by viral infections, though other etiologies must be considered. A thorough history and physical examination, including strobovideolaryngoscopy and laryngeal electromyography, are needed for definitive diagnosis. It is essential to establish the diagnosis accurately to differentiate an apparent superior laryngeal nerve paresis from other conditions, such as myasthenia gravis. Laryngeal electromyography is used to confirm clinical impressions, as a guide for therapy, and as one measure of recovery. In our experience, accurate and early diagnosis assure the best phonatory outcome by directing therapy that will prevent or eliminate compensatory vocal abuses, which may themselves lead to even more serious vocal injury.

Adolescent↗

PubMed1996

Urologic manifestation of spinal cord sarcoidosis.

We present the first report of neurogenic lower urinary tract dysfunction associated with neurosarcoidosis. Urodynamic findings of detrusor hyperreflexia with detrusor-sphincter dyssynergia correlate with this patient's magnetic resonance imaging (MRI) examination which found intramedullary involvement at the mid-thoracic level.

Adult↗

PubMed1996

Induction of meiosis in Saccharomyces cerevisiae depends on conversion of the transcriptional represssor Ume6 to a positive regulator by its regulated association with the transcriptional activator Ime1.

The transcription of meiosis-specific genes, as well as the initiation of meiosis, in the budding yeast Saccharomyces cerevisiae depends on IME1. IME1 encodes a transcriptional activator which lacks known DNA binding motifs. In this study we have determined the mode by which Ime1 specifically activates the transcription of meiotic genes. We demonstrate that Ime1 is recruited to the promoters of meiotic genes by interacting with a DNA-binding protein, Ume6. This association between Ime1 and Ume6 depends on both starvation and the activity of a protein kinase, encoded by RIM11 In the absence of Ime1, Ume6 represses the transcription of meiotic genes. However, in the presence of Ime1, or when Ume6 is fused in frame to the Gal4 activation domain, Ume6 is converted from a repressor to an activator, resulting in the transcription of meiosis-specific genes and the formation of asci.

Base Sequence↗

PubMed1996

Urological symptomatology in patients with reflex sympathetic dystrophy.

PURPOSE: We determined the effect of reflex sympathetic dystrophy on lower urinary tract function. MATERIALS AND METHODS: A total of 20 consecutive patients (16 women and 4 men) with neurologically verified reflex sympathetic dystrophy was referred for voiding symptoms, including urgency, frequency, incontinence and urinary retention. No patient had had voiding symptoms before the initial trauma that induced reflex sympathetic dystrophy. Evaluation included medical history, physical examination, video urodynamic testing and cystoscopy. RESULTS: Mean patient age was 43.4 +/- 10.2 years (range 28 to 58) and mean duration of urological symptoms was 4.9 +/- 3.6 years (range 1 to 14). Urodynamic study demonstrated a mean cystometric bladder capacity of 417 +/- 182 ml. (range 120 to 700). The urodynamic diagnoses included detrusor hyperreflexia in 8 patients, detrusor areflexia in 8, sensory urgency in 3 and detrusor hyperreflexia with detrusor-external sphincter dyssynergia in 1. In 4 women genuine stress urinary incontinence was also documented urodynamically. CONCLUSIONS: Reflex sympathetic dystrophy may have a profound effect on detrusor and sphincter function.

Adult↗

PubMed1996

Neurogenic stuttering: further corroboration of site of lesion.

Cases of neurogenic stuttering have been reported in the literature throughout the past century. Site(s) of lesion(s) have been documented usually by association of symptoms, EEG studies and occasionally by computed tomography (CT). The authors present three cases in which the site(s) of lesion(s) are documented by CT, magnetic resonance imaging (MRI) and SPECT. This study supports previous findings of neurogenic stuttering following either bilateral diffuse lesions or a unilateral lesion. In at least one case, the actual site of the lesion would have been missed without the use of SPECT testing. EEG studies were not helpful in identifying the site of the lesion.

Adult↗

PubMed1996

Single-photon-emission computed tomography (SPECT) in neurotologic assessment: a preliminary report.

The single-photon-emission computed tomography (SPECT) scan enables clinicians to probe dynamic and metabolic changes in brain tissue through measurement of regional cerebral blood flow (rCBF). Diagnostic benefits of the SPECT scan in clinical neurology have been demonstrated. SPECT scanning has been shown to be more sensitive than morphologic imaging techniques [magnetic resonance imaging (MRI) and computed tomography (CT)] in many conditions. However, the use of the scan in assessing neurotologic complaints remains inadequately investigated. Few studies have explored the value of SPECT in establishing the causes of dizziness, hearing loss, and tinnitus. We studied SPECT along with MRI, CT scan, electroencephalogram (EEG), and other evaluations in patients with these neurotologic complaints, SPECT abnormalities were more frequent and prominent than those visualized by other imaging modalities. Overall, 78% of SPECT scans revealed abnormalities. Abnormalities were found in 46% of MRIs, 40% of CTs, and 29% of EEGs. The disparity between SPECT scanning and other procedures was also seen once patients were divided by their chief complaints. This study illustrates the sensitivity of SPECT scanning in evaluating neurotologic complaints and highlights the need for additional research into the importance of SPECT scanning in comprehensive neurotologic evaluation.

Brain↗

PubMed1995

Free amino acids can replace protein-bound amino acids in test diets for studies in rainbow trout (Oncorhynchus mykiss).

Effects of reducing dietary concentration of protein-bound amino acids on growth, feed intake and composition of gain in rainbow trout were studied in four experiments. Average initial body weights ranged between 29 +/- 0.7 and 55 +/- 0.5 g per trout. Diets contained approximately 20 MJ digestible energy/kg dry matter. Each diet was fed to satiation to four replicate groups of 20 trout. Feed intake and growth rates were recorded for each group. Body composition was analyzed in representative groups at the start of each experiment and in all experimental groups at the end of each experiment. Reduction of dietary protein concentration to < 380 g/kg dry matter caused significantly lower growth rates and reduced protein concentrations of gain, but these reductions in growth could be offset by the addition of 10 crystalline essential amino acids. Fish meal was completely replaced by a mixture of wheat gluten and crystalline amino acids without negative influences on growth. In the absence of fish meal, almost half the wheat gluten could be replaced by crystalline amino acids in diets containing about 32 g N x 6.25/kg dry matter without significant influences on growth. In such diets, concentrations of individual amino acids may be varied widely with no variation in other amino acids or nutrients.

Amino Acids↗

PubMed1995

Reflex sympathetic dystrophy revisited: MR imaging findings before and after infusion of contrast material.

PURPOSE: To determine the appearance of reflex sympathetic dystrophy (RSD) at magnetic resonance (MR) imaging. MATERIALS AND METHODS: Fifty-one patients with suspected RSD were prospectively evaluated at MR imaging with T1- and T2-weighted sequences and T1-weighted sequences with fat suppression before and after the intravenous administration of contrast material. RESULTS: RSD was confirmed in 45 patients. In 35 patients with stage 1 RSD, skin thickening (31 patients), tissue enhancement with contrast material (31 patients), and soft-tissue edema (six patients) were demonstrated. In five patients with stage 2 RSD, skin thickening (two patients), skin thinning (two patients), and infrequent contrast material enhancement (one patient) were demonstrated. There was no edema in this group of patients. In five patients with stage 3 RSD, inconsistent skin changes were also demonstrated; however, muscle atrophy (four patients) was demonstrated in this stage only. CONCLUSION: MR imaging was beneficial in the demonstration of soft-tissue abnormalities in patients with RSD. MR imaging may also help stage RSD, particularly stages 1 and 3.

Adult↗

PubMed1995

Changes in insulin-like growth factor-I (IGF-I), IGF-binding protein-3, growth hormone (GH)-binding protein, erythrocyte IGF-I receptors, and growth rate during GH treatment.

To assess the relative determinants of growth rate, we measured serum levels of insulin-like growth factor-I (IGF-I), IGF-binding protein-3 (IGFBP-3), and GH-binding protein (GHBP) as well as IGF-I erythrocyte receptor specific binding (SB) in 14 prepubertal GH-deficient children before and during the first year of treatment with 0.043 mg/kg.day GH. Serum IGF-I and IGFBP-3 levels, measured by RIA, were significantly increased by 2 weeks and showed progressive increases throughout the year of GH therapy. Growth rate (height velocity SD score adjusted for bone age) correlated best with the 12 month changes in IGFBP-3 (r = 0.81; P < 0.001) and IGF-I (r = 0.72; P = 0.005), and to a lesser extent with the 12 month absolute IGFBP-3 (r = 0.58; P = 0.04) and the 6 month change in IGFBP-3 (r = 0.55; P = 0.05). The baseline IGF-I correlated inversely with the growth rate during GH therapy (r = -0.55; P = 0.05) and was the best pretreatment predictor of growth response. GHBP, as measured by ligand-mediated immunofunctional assay, showed no significant change during GH therapy and did not correlate with growth response. The baseline GHBP, however, did correlate with both the 12 month IGFBP-3 (r = 0.72; P = 0.006) as well as the 2 week change in IGFBP-3 (r = 0.63; P = 0.05). Erythrocyte IGF-I SB showed a significant decrease by 6 months secondary to a decrease in IGF-I receptor number, with no change in affinity. The 6 month IGF-I receptor binding correlated inversely with the increase in IGF-I (r = -0.88; P < 0.001). Erythrocyte IGF-I SB at baseline did not correlate with the growth response, although there was an inverse trend between the 6 month IGF-I receptor level and the growth rate. IGF-I and IGFBP-3 show progressive increases, whereas the erythrocyte IGF-I receptor-binding capacity decreases by 6 months, and GHBP shows little change during the first year of GH treatment. Data from this study suggest that changes in IGFBP-3 and, to a lesser extent, IGF-I are the major correlates of growth rate, and that down-regulation of the IGF-I receptor may have relatively little influence on growth rate compared with changes in IGFBP-3 and IGF-I.

Body Mass Index↗

PubMed1994

IME1 gene encodes a transcription factor which is required to induce meiosis in Saccharomyces cerevisiae.

Previous studies have shown that the IME1 gene is required for sporulation and the expression of meiosis specific genes in Saccharomyces cerevisiae. However, sequence analysis has not revealed the precise functional role of the Ime1 protein. By engineering constructs which express various portions of the Ime1p fused to either the DNA binding or transcriptional activation domains of GAL4, we have conclusively demonstrated that IME1 is a transcription factor, apparently required for sporulation to activate the transcription of meiosis specific genes. The full Ime1p, when fused to the GAL4 DNA binding domain, can both activate GAL1-lacZ expression, and complement ime1-0 (a null allele) for the ability to sporulate, and transcriptionally activate IME2, a meiosis specific gene. As successively larger portions of the encoded Ime1p N-terminus are deleted from the GAL4(bd)-IME1 construct, the encoded fusion proteins retain the ability to complement an ime1 null allele, despite a decreasing ability to activate GAL1-lacZ transcription. However, a fusion construct which retains only the last 45 C-terminal amino acids of IME1 provides neither transcriptional activation of GAL1-lacZ nor complementation of ime1-0. Fusion of a GAL4 activation domain to this portion of IME1, results in a construct with a restored ability to complement an ime1-0 allele. This restored ability is dependent upon galactose induction. We conclude, therefore, that IME1 functions in meiosis as a transcriptional activator.

Base Sequence↗

PubMed1994

Preoperative diagnostic evaluation of children with Cushing's syndrome.

Recent advances in biochemical and imaging studies have improved the diagnostic accuracy of Cushing's syndrome. To better define roles for these studies in children, the authors reviewed their experience with this rare group of patients. Fifteen children, aged 11 weeks to 17 years, were treated for noniatrogenic Cushing's syndrome over a 33-year period. All children presented with signs of hypercortisolism. Nineteen different diagnostic tests were used, reflecting changes in how these patients are evaluated. Pathological diagnoses were adrenal cortical carcinoma (3), primary adrenocortical nodular dysplasia (PAND) (2), and pituitary adenoma (10). Children with adrenal cortical carcinoma presented with an adrenal mass and at a younger age (mean, 22.3 months). Key diagnostic features of patients with PAND were a low plasma adrenocorticotrophin hormone (ACTH) and no suppression with high-dose dexamethasone. Children with a pituitary cause of Cushing's syndrome presented at an older age (mean, 15.7 years) and were diagnosed using a combination of high-dose dexamethasone testing, simultaneous inferior petrosal sinus sampling, and/or ovine corticotrophin-releasing hormone stimulation test. A strategy for the diagnosis of Cushing's syndrome in children is presented.

Adenoma↗

PubMed1994

Studies on limiting essential amino acids in grieves as source of dietary protein for rainbow trout (Oncorhynchus mykiss).

Diets were computed to contain equal concentrations of digestible crude protein either of wheat gluten (diet 1) or of grieves (diets 2-8). Per kg dry diet, 41 g crystalline amino acids were supplemented. All diets contained at least 1.2 g Lys per MJ digestible energy (DE). In diet 2, ratios of Met + Cys, Trp, Leu, Ile and Phe to Lys were about equal to those in diet 1. In each of diets 3-7, one of the respective amino acids, in diet 8 all five were replaced by Glu in the supplemented mixture of amino acids. Each diet was fed to triplicate groups of 20 trout during a trial lasting 66 days. Trout fed the diet containing wheat gluten consumed more dry matter and showed higher growth rates as well as higher protein contents in their gained body mass than trout fed diets based on grieves. Supplementing Met plus Trp significantly improved dry matter intake, growth rate and protein content of gain, though not to the level of trout fed the wheat gluten diet, whereas Leu, Ile and Phe showed no such effect. When grieves were not supplemented with both Met and Trp, gain in body mass contained significantly more lipids. DE required per kg gain by trout fed wheat gluten, grieves + Met + Trp or grieves without supplementation of Met and Trp was 20.1, 21.2 and 29.9 MJ, respectively.

Adipose Tissue↗

PubMed1994

Superior sagittal sinus thrombosis in the presence of idiopathic bilateral internal jugular vein stenosis.

Cerebral venous outflow obstruction and anomalies in cerebral venous circulation predispose to dural sinus thrombosis. This case report illustrates the magnetic resonance and angiographic findings in a patient who had superior sagittal sinus thrombosis secondary to idiopathic bilateral internal jugular vein stenosis, a previously unrecognized entity. The findings suggest that bilateral stenosis of the internal jugular veins at their junction with the innominate veins causes obstruction to cerebral venous outflow leading to dural sinus thrombosis.

Constriction, Pathologic↗