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Mean Latency (mean + latency)
Selected AbstractsCyclosporine Induces Epileptiform Activity in an In Vitro Seizure ModelEPILEPSIA, Issue 3 2000Michael Wong Summary: Purpose: Cyclosporine (CSA) toxicity represents a common cause of seizures in transplant patients, but the specific mechanisms by which CSA induces seizures are unknown. Although CSA may promote seizure activity by various metabolic, toxic, vascular, or structural mechanisms, CSA also has been hypothesized to modulate neuronal excitability directly. The objective of this study was to determine if CSA exerts direct epileptogenic actions on neurons in an in vitro seizure model. Methods: Combined hippocampal-entorhinal cortex slices from juvenile rats were exposed directly to artificial cerebro-spinal fluid (ACSF) containing either (a) 1.0 mM magnesium sulfate (control), (b) 1.0 mM sodium sulfate (low-magnesium), or (c) 1.0 mM magnesium sulfate + CSA (1,000,10,000 ng/ml). Spontaneous and evoked extracellular field potentials were recorded simultaneously from the dentate gyrus (DG) and CA3 hippocampal regions. Evoked synaptic responses were elicited by stimulation of the entorhinal cortex/perforant pathway. Results: CSA elicited spontaneous or stimulation-induced epileptiform activity in the DG or CA3 region of ,40% of slices, consisting of brief repetitive "interictal" discharges or prolonged stereotypical "ictal" discharges. Mean latency to epileptiform activity was ,100 min after onset of CSA application. The interictal discharges were inhibited by the non-NMDA antagonist, NBQX. Similar epileptiform activity was observed in low-magnesium ACSF without CSA. In control ACSF alone, epileptiform activity was not seen, except for rare spontaneous potentials in the DG. Conclusions: Direct effects of CSA on neuronal excitability and synaptic transmission may contribute to seizures seen in clinical CSA neurotoxicity. [source] Outcome predictors, efficacy and safety of Botox and Dysport in the long-term treatment of hemifacial spasmEUROPEAN JOURNAL OF NEUROLOGY, Issue 3 2009A. R. Bentivoglio Background and purpose:, To review the clinical characteristics and the long-term outcome of patients with hemifacial spasm (HFS) who received botulinum neurotoxin (BoNT) over the past 10 years. Results:, A total of 108 patients received 665 treatments. Mean latency of clinical effect was 5.4 ± 5.3 days for Botox and 4.9 ± 4.6 days for Dysport (P > 0.05). Mean duration of clinical improvement was higher after the injection of Dysport than Botox: 105.9 ± 54.2 and 85.4 ± 41.6 days respectively (P < 0.01). The percentage of treatment failures was 6.5% for Botox and 4.6% for Dysport (P > 0.05). The doses of Botox significantly increased over time (, = 0.35, P < 0. 001) whilst Dysport dose remained unchanged (, = 0.16, n.s.). The duration of clinical benefit slightly increased with Botox (, = 0.12; P < 0.01), but remained constant for Dysport. Side effects occurred in 17.4% of treatments: 16.7% of patients who had received Botox, and in 19.7% who had received Dysport (P > 0.05). The most common side effects were palpebral ptosis and lacrimation; ptosis and lagophtalmos was more common in Dysport treatments (P < 0.005). Conclusions:, Both brands are effective and safe in treating HFS; efficacy is long-lasting. The differences in outcome and side effects confirm that, albeit the active drug is the same, Botox and Dysport should be considered as two different drugs. [source] Clinical and electromyographic deep tendon reflexes in polyneuropathy: diagnostic value and prevalence,ACTA NEUROLOGICA SCANDINAVICA, Issue 4 2009K. R. Sharma Background,,, Evidence is accumulating that patients with polyneuropathy may present with normal clinical deep tendon reflexes (C-DTR). There are few studies that assessed the diagnostic utility of electromyographically recorded DTR (Er-DTR) in patients with polyneuropathy. Objectives,,, The objectives of this study were twofold: (i) to evaluate the prevalence of preserved C-DTR in polyneuropathy; (ii) diagnostic value of Er-DTR latency measurement in patients with polyneuropathy. Methods,,, We prospectively studied 38 controls and 185 patients with polyneuropathy. All subjects had evaluation of C-DTR, Er-DTR obtained from right biceps brachii (BR), right patellar (PR) and bilateral ankle reflexes (AR). Results,,, Of these 185 patients, 118 (63.8%) had chronic axonal neuropathy (CAN), 49 (26.5%) demyelinating polyradiculoneuropathy (DPN) and 18 (9.7%) small fiber neuropathy (SFN). The C-DTR were normal in 65 patients whereas 39 of these 65 (60%) patients had abnormalities of Er-DTR at one or more sites. Er-DTR latencies in patients with polyneuropathies were prolonged at all sites compared with controls (P < 0.01). Among patients with various types of polyneuropathies the Er-DTR, mean latencies at all the sites and latency indicative of demyelination (>150% of the normal mean) were higher in patients with DPN than that of CAN or SFN (P < 0.01). Conclusions,,, We conclude that C-DTR are preserved in 35.1% of the patients with polyneuropathies and Er-DTR should be performed in such patients in order to provide electrophysiological evidence of a polyneuropathy. Er-DTR are useful in distinguishing axonal from demyelinating disorders of peripheral nerve, and detection of subclinical involvement of large fibers in SFN. [source] Green tea extracts decrease carcinogen-induced mammary tumor burden in rats and rate of breast cancer cell proliferation in cultureJOURNAL OF CELLULAR BIOCHEMISTRY, Issue 3 2001Kathryn T. Kavanagh Abstract Epidemiological evidence suggests tea (Camellia sinensis L.) has chemopreventive effects against various tumors. Green tea contains many polyphenols, including epigallocatechin-3 gallate (EGCG), which possess anti-oxidant qualities. Reduction of chemically induced mammary gland carcinogenesis by green tea in a carcinogen-induced rat model has been suggested previously, but the results reported were not statistically significant. Here we have tested the effects of green tea on mammary tumorigenesis using the 7,12-dimethylbenz(a)anthracene (DMBA) Sprague-Dawley (S-D) rat model. We report that green tea significantly increased mean latency to first tumor, and reduced tumor burden and number of invasive tumors per tumor-bearing animal; although, it did not affect tumor number in the female rats. Furthermore, we show that proliferation and/or viability of cultured Hs578T and MDA-MB-231 estrogen receptor-negative breast cancer cell lines was reduced by EGCG treatment. Similar negative effects on proliferation were observed with the DMBA-transformed D3-1 cell line. Growth inhibition of Hs578T cells correlated with induction of p27Kip1 cyclin-dependent kinase inhibitor (CKI) expression. Hs578T cells expressing elevated levels of p27Kip1 protein due to stable ectopic expression displayed increased G1 arrest. Thus, green tea had significant chemopreventive effects on carcinogen-induced mammary tumorigenesis in female S-D rats. In culture, inhibition of human breast cancer cell proliferation by EGCG was mediated in part via induction of the p27Kip1 CKI. J. Cell. Biochem. 82:387,398, 2001. © 2001 Wiley-Liss, Inc. [source] The inhibitory effect of a chewing task on a human jaw reflexMUSCLE AND NERVE, Issue 6 2010Pauline Maillou BDS Abstract This study was undertaken to investigate whether an inhibitory jaw reflex could be modulated by experimentally controlled conditions that mimicked symptoms of temporomandibular disorders. Reflecting on previous work, we anticipated that these conditions might suppress the reflex. Electromyographic recordings were made from a masseter muscle in 18 subjects, while electrical stimuli were applied to the upper lip. An inhibitory reflex wave (mean latency 47 ms) was identified and quantified. Immediately following an accelerated chewing task, which in most cases produced muscle fatigue and/or pain, the size of the reflex wave decreased significantly by about 30%. The suppression of inhibitory jaw reflexes by fatigue and pain may result in positive feedback, which may contribute to the symptoms of temporomandibular disorders. Future studies of temporomandibular disorder sufferers will help to determine whether such reflex changes reflect the underlying etiology and/or are a result of the temporomandibular disorder itself. Muscle Nerve, 2010 [source] Clinical utility of dorsal sural nerve conduction studiesMUSCLE AND NERVE, Issue 6 2001James M. Killian MD Abstract A technique of testing sensory nerve conduction of the dorsal sural nerve in the foot was used in 38 normal subjects and 70 patients with peripheral neuropathies. The normal dorsal sural sensory nerve action potential (SNAP) had a mean amplitude of 8.9 ,V (range 5,15 ,V), mean latency to negative peak of 4.0 ms (range 3.2,4.7 ms), and mean conduction velocity of 34.8 m/s (range 30,44 m/s). Optimal placement of the recording electrodes to obtain a maximal nerve action potential was proximal to digits 4 and 5. Cooling to below 25°C prolonged the latency but did not decrease the SNAP amplitude. Among the patients with peripheral neuropathy, dorsal sural SNAP was absent in 68 (97%), whereas only 54 (77%) showed abnormalities of sural sensory conduction. The diagnostic sensitivity of sensory nerve conduction studies in peripheral neuropathies may be significantly improved by the use of this technique for evaluating the action potential of the dorsal sural nerve. © 2001 John Wiley & Sons, Inc. Muscle Nerve 24: 817,820, 2001 [source] Progesterone for maintenance tocolytic therapy after threatened preterm labour: A randomised controlled trialAUSTRALIAN AND NEW ZEALAND JOURNAL OF OBSTETRICS AND GYNAECOLOGY, Issue 1 2008Sedigheh BORNA Background: Women with preterm labour that is arrested with tocolytic therapy are at increased risk of recurrent preterm labour. The efficacy of maintenance tocolytic therapy after successful arrest of preterm labour remains controversial. Aim: The purpose of this study was to determine whether supplementation of vaginal progesterone after inhibition of preterm labour is associated with an increased latency period and a decreased recurrent of preterm labour. Methods: This trial was conducted in 70 women who presented with symptoms of threatened preterm labour, who after arrest of uterine activity were then randomised to progesterone therapy or no treatment. Treatment group received progesterone suppository (400 mg) daily until delivery and control group received no treatment. Results: Longer mean latency until delivery (36/11 ± 17/9 vs 24/52 ± 27/2) (mean + standard deviation) days; respiratory distress syndrome 4 (10.8%) vs 12 (36.4%) P = 0.021; low birthweight 10 (27%) vs 17 (51.5%) P = 0.04; and birthweight (3101.54 ± 587.9 g vs r 2609.39 ± 662.9 g, P = 0.002), were significantly different between the two groups. No significant differences were found between recurrent preterm labour 13 (35.1%) vs 19 (57.6%), P = 0.092; admission to intensive care unit 9 (24.3%) vs 13 (39.4%), P= 0.205 ; and neonatal sepsis 2 (5.4%) vs 6 (18.2%) P = 0.136, for the progesterone and control groups, respectively. Conclusion: The use of vaginal progesterone suppository after successful parenteral tocolysis associated with a longer latency preceding delivery but failed to reduce the incidence of readmission for preterm labour. [source] Pulmonary function tests and diaphragmatic compound muscle action potential in patients with sporadic amyotrophic lateral sclerosisACTA NEUROLOGICA SCANDINAVICA, Issue 6 2010T. N. Sathyaprabha Sathyaprabha TN, Pradhan C, Nalini A, Thennarasu K, Raju TR. Pulmonary function tests and diaphragmatic compound muscle action potential in patients with sporadic amyotrophic lateral sclerosis. Acta Neurol Scand: 2010: 121: 400,405. © 2010 The Authors Journal compilation © 2010 Blackwell Munksgaard. Background,,, Respiratory failure is the primary cause of death in patients with amyotrophic lateral sclerosis (ALS). Diaphragmatic compound muscle action potentials (DCMAP) are valid parameters to assess the respiratory muscle innervation. Aim,,, In this study we propose to establish evidence of pulmonary dysfunction in patients with ALS and its relation to DCMAP parameters among patients with sporadic ALS. Materials and methods,,, Twenty nine patients (M-20, F-9) diagnosed to have sporadic ALS by El. Escorial criteria, without symptoms of pulmonary dysfunction, and able to perform the PFT satisfactorily, were studied. Thirty controls (M-20, F-10) were selected from patient's relatives. Forced vital capacity (FVC), forced expiratory volume in one second (FEV1), peak expiratory flow rate (PEFR) and maximum voluntary ventilation (MVV) were measured by spirometry. Maximum expiratory pressure (MEP) was measured by digital peak pressure monitor. Right phrenic nerve conductions (DCMAP) were performed and the latencies and amplitude of diaphragmatic com-pound action potential (DCMAP) was recorded in controls and ALS patients. Results,,, The mean age of patients was 51.41 ± 10.72 years (37,82) and control was 53.57 ± 8.85 years (30,68). None of the patients had symptoms or clinical evidence of respiratory dysfunction. The FVC, FEV1, PEFR, MVV, MIP and MEP were significantly (P < 0.001) reduced in ALS. The mean DCMAP amplitude was reduced among patients (610 ± 506.231 ,v) as compared to controls (1303.33 ± 584.56, P < 0.001) and mean latency was increased in patients (9.73 ± 2.57 ms) compared to controls (7.69 ± 0.87, P = 0.001). There was significant negative correlation between PFTs and latencies of DCMAP. Amplitude of DCMAP did not correlate with PFTs. Conclusion,,, There is significant negative correlation between DCMAP latencies and PFTs suggesting early loss of myelinated fibres and diaphragmatic dysfunction. DCMAP latencies may be a good indicator of early respiratory muscle involvement and also of disease progression in ALS. [source] | ||||||||||