ABSTRACT
BACKGROUND: Several patient-reported outcome measures (PROMs) have been developed for research to assess the multiple dimensions of chronic pruritus (CP). The acceptability and perceived benefits of their use in clinical practice remain unknown. OBJECTIVES: To assess the acceptability and perceived benefits of validated PROMs from the perspective of patients and physicians in dermatological offices and clinics. METHODS: Patients with CP due to atopic dermatitis, psoriasis, chronic prurigo or chronic urticaria were recruited at 10 dermatological offices and two dermatological clinics in Germany. Patients completed a set of validated PROMs on pruritus intensity (numerical rating scale, NRS), symptom control (itch-controlled days, ItchCD), quality of life (Dermatology Life Quality Index, DLQI; 5-pruritus life quality, 5PLQ) and general health status (EuroQol, EQ-VAS). Acceptability (relevance, difficulty of completion, length) and benefits (usefulness, feasibility) of these tools were assessed on a NRS (0-10) by patients and physicians, respectively. Data were analysed descriptively. Linear regression was used to study potential associations between age, sex, occupation, office versus clinic, change of therapy and physician-reported benefits. RESULTS: N = 523 patients (46% male, average age: 53.5 years) participated. Acceptability of PROMs by patients was high, indicated by low difficulty (Md = 0, IQR = 0-1 for all PROMs) and high relevance (Md = 8, IQR = 4-10 for all PROMs). Also, most patients (89-95%) rated length of the questionnaires as 'exactly right'. Physicians rated the NRS as the most beneficial instrument (feasibility: Md = 8, IQR = 6-10; usefulness: Md = 9, IQR = 7-10). Hierarchical linear regression revealed that only recruitment site (dermatological office vs. clinic) was significantly associated with usefulness and feasibility (higher ratings for clinical context; ßs = 0.149-0.258, ps <0.05; except feasibility for EQ5d, ß = ns). CONCLUSION: PROMs are welcomed by patients, while physicians consider instruments measuring pruritus intensity and impairment of quality of life as beneficial for the clinical routine. Widespread implementation of PROMs in daily clinical work is needed to improve care.
ABSTRACT
We present results from an analysis of all data taken by the BICEP2, Keck Array, and BICEP3 CMB polarization experiments up to and including the 2018 observing season. We add additional Keck Array observations at 220 GHz and BICEP3 observations at 95 GHz to the previous 95/150/220 GHz dataset. The Q/U maps now reach depths of 2.8, 2.8, and 8.8 µK_{CMB} arcmin at 95, 150, and 220 GHz, respectively, over an effective area of ≈600 square degrees at 95 GHz and ≈400 square degrees at 150 and 220 GHz. The 220 GHz maps now achieve a signal-to-noise ratio on polarized dust emission exceeding that of Planck at 353 GHz. We take auto- and cross-spectra between these maps and publicly available WMAP and Planck maps at frequencies from 23 to 353 GHz and evaluate the joint likelihood of the spectra versus a multicomponent model of lensed ΛCDM+r+dust+synchrotron+noise. The foreground model has seven parameters, and no longer requires a prior on the frequency spectral index of the dust emission taken from measurements on other regions of the sky. This model is an adequate description of the data at the current noise levels. The likelihood analysis yields the constraint r_{0.05}<0.036 at 95% confidence. Running maximum likelihood search on simulations we obtain unbiased results and find that σ(r)=0.009. These are the strongest constraints to date on primordial gravitational waves.
ABSTRACT
PURPOSE: This study evaluates the capacity of ultrasonography as a diagnostic method to confirm the proper positioning of central venous catheter (CVC) when compared to the current gold standard, chest radiography (CR). METHODS: A prospective study was performed including children from 0 to 14 incomplete years, who underwent CVC placement between March and May 2018 at a teaching hospital in Brazil. A four-chamber view of the heart was performed with ultrasound during a rapid injection of saline solution to identify hyperechoic images and confirm the central position of the catheter. After that, a CR was performed. The diagnostic quality of ultrasound was evaluated based on accuracy, sensitivity, specificity, positive and negative predictive values. RESULTS: A total of 21 patients were analyzed. The mean age was 3.95 ± 4.01 years. The preferred puncture site was the right internal jugular vein (71.4%). Ultrasound accuracy to detect CVC positioning was 81%. Sensitivity, specificity and positive and negative predictive values were 33%, 100%, 100% and 79%, respectively. CONCLUSION: Ultrasound is a reliable method for detection of CVC positioning. Even so, with the four-chamber cardiac view, this method is unable to identify catheters inside heart chambers, therefore, needing to confirm the positioning with CR.
Subject(s)
Catheterization, Central Venous/methods , Central Venous Catheters , Jugular Veins/diagnostic imaging , Radiography, Thoracic/methods , Ultrasonography/methods , Adolescent , Brachiocephalic Veins , Child , Child, Preschool , Equipment Design , Female , Humans , Infant , Infant, Newborn , Male , Prospective Studies , PuncturesABSTRACT
We present results from an analysis of all data taken by the bicep2/Keck CMB polarization experiments up to and including the 2015 observing season. This includes the first Keck Array observations at 220 GHz and additional observations at 95 and 150 GHz. The Q and U maps reach depths of 5.2, 2.9, and 26 µK_{CMB} arcmin at 95, 150, and 220 GHz, respectively, over an effective area of ≈400 square degrees. The 220 GHz maps achieve a signal to noise on polarized dust emission approximately equal to that of Planck at 353 GHz. We take auto and cross spectra between these maps and publicly available WMAP and Planck maps at frequencies from 23 to 353 GHz. We evaluate the joint likelihood of the spectra versus a multicomponent model of lensed-ΛCDM+r+dust+synchrotron+noise. The foreground model has seven parameters, and we impose priors on some of these using external information from Planck and WMAP derived from larger regions of sky. The model is shown to be an adequate description of the data at the current noise levels. The likelihood analysis yields the constraint r_{0.05}<0.07 at 95% confidence, which tightens to r_{0.05}<0.06 in conjunction with Planck temperature measurements and other data. The lensing signal is detected at 8.8σ significance. Running a maximum likelihood search on simulations we obtain unbiased results and find that σ(r)=0.020. These are the strongest constraints to date on primordial gravitational waves.
ABSTRACT
We present results from an analysis of all data taken by the BICEP2 and Keck Array cosmic microwave background (CMB) polarization experiments up to and including the 2014 observing season. This includes the first Keck Array observations at 95 GHz. The maps reach a depth of 50 nK deg in Stokes Q and U in the 150 GHz band and 127 nK deg in the 95 GHz band. We take auto- and cross-spectra between these maps and publicly available maps from WMAP and Planck at frequencies from 23 to 353 GHz. An excess over lensed ΛCDM is detected at modest significance in the 95×150 BB spectrum, and is consistent with the dust contribution expected from our previous work. No significant evidence for synchrotron emission is found in spectra such as 23×95, or for correlation between the dust and synchrotron sky patterns in spectra such as 23×353. We take the likelihood of all the spectra for a multicomponent model including lensed ΛCDM, dust, synchrotron, and a possible contribution from inflationary gravitational waves (as parametrized by the tensor-to-scalar ratio r) using priors on the frequency spectral behaviors of dust and synchrotron emission from previous analyses of WMAP and Planck data in other regions of the sky. This analysis yields an upper limit r_{0.05}<0.09 at 95% confidence, which is robust to variations explored in analysis and priors. Combining these B-mode results with the (more model-dependent) constraints from Planck analysis of CMB temperature plus baryon acoustic oscillations and other data yields a combined limit r_{0.05}<0.07 at 95% confidence. These are the strongest constraints to date on inflationary gravitational waves.
ABSTRACT
We report the results of a joint analysis of data from BICEP2/Keck Array and Planck. BICEP2 and Keck Array have observed the same approximately 400 deg^{2} patch of sky centered on RA 0 h, Dec. -57.5°. The combined maps reach a depth of 57 nK deg in Stokes Q and U in a band centered at 150 GHz. Planck has observed the full sky in polarization at seven frequencies from 30 to 353 GHz, but much less deeply in any given region (1.2 µK deg in Q and U at 143 GHz). We detect 150×353 cross-correlation in B modes at high significance. We fit the single- and cross-frequency power spectra at frequencies ≥150 GHz to a lensed-ΛCDM model that includes dust and a possible contribution from inflationary gravitational waves (as parametrized by the tensor-to-scalar ratio r), using a prior on the frequency spectral behavior of polarized dust emission from previous Planck analysis of other regions of the sky. We find strong evidence for dust and no statistically significant evidence for tensor modes. We probe various model variations and extensions, including adding a synchrotron component in combination with lower frequency data, and find that these make little difference to the r constraint. Finally, we present an alternative analysis which is similar to a map-based cleaning of the dust contribution, and show that this gives similar constraints. The final result is expressed as a likelihood curve for r, and yields an upper limit r_{0.05}<0.12 at 95% confidence. Marginalizing over dust and r, lensing B modes are detected at 7.0σ significance.
ABSTRACT
We report results from the BICEP2 experiment, a cosmic microwave background (CMB) polarimeter specifically designed to search for the signal of inflationary gravitational waves in the B-mode power spectrum around ââ¼80. The telescope comprised a 26 cm aperture all-cold refracting optical system equipped with a focal plane of 512 antenna coupled transition edge sensor 150 GHz bolometers each with temperature sensitivity of ≈300 µK(CMB)âs. BICEP2 observed from the South Pole for three seasons from 2010 to 2012. A low-foreground region of sky with an effective area of 380 square deg was observed to a depth of 87 nK deg in Stokes Q and U. In this paper we describe the observations, data reduction, maps, simulations, and results. We find an excess of B-mode power over the base lensed-ΛCDM expectation in the range 30 < â < 150, inconsistent with the null hypothesis at a significance of >5σ. Through jackknife tests and simulations based on detailed calibration measurements we show that systematic contamination is much smaller than the observed excess. Cross correlating against WMAP 23 GHz maps we find that Galactic synchrotron makes a negligible contribution to the observed signal. We also examine a number of available models of polarized dust emission and find that at their default parameter values they predict power â¼(5-10)× smaller than the observed excess signal (with no significant cross-correlation with our maps). However, these models are not sufficiently constrained by external public data to exclude the possibility of dust emission bright enough to explain the entire excess signal. Cross correlating BICEP2 against 100 GHz maps from the BICEP1 experiment, the excess signal is confirmed with 3σ significance and its spectral index is found to be consistent with that of the CMB, disfavoring dust at 1.7σ. The observed B-mode power spectrum is well fit by a lensed-ΛCDM+tensor theoretical model with tensor-to-scalar ratio r = 0.20_(-0.05)(+0.07), with r = 0 disfavored at 7.0σ. Accounting for the contribution of foreground, dust will shift this value downward by an amount which will be better constrained with upcoming data sets.
ABSTRACT
Previously observed non-Arrhenius behavior in fast ion conducting glasses [J. Kincs and S. W. Martin, Phys. Rev. Lett. 76, 70 (1996)] occurs at temperatures near the glass transition temperature, T(g), and is attributed to changes in the ion mobility due to ion trapping mechanisms that diminish the conductivity and result in a decreasing conductivity with increasing temperature. It is intuitive that disorder in glass will also result in a distribution of the activation energies (DAE) for ion conduction, which should increase the conductivity with increasing temperature, yet this has not been identified in the literature. In this Letter, a series of high precision ionic conductivity measurements are reported for 0.5Na(2)S + 0.5[xGeS(2) + (1-x)PS(5/2)] glasses with compositions ranging from 0 ≤ x ≤ 1. The impact of the cation site disorder on the activation energy is identified and explained using a DAE model. The absence of the non-Arrhenius behavior in other glasses is explained and it is predicted which glasses are expected to accentuate the DAE effect on the ionic conductivity.
ABSTRACT
A new S2k AWMF guideline for the treatment of idiopathic facial palsy has been published. An accurate differential diagnosis is indispensable as 25-40% of all facial palsy cases are of non-idiopathic origin. It is explicitly recommended to treat patients with idiopathic facial palsy with steroids. Steroids favour a complete recovery, decrease the risk of synkinesis, autonomic sequelae and contractures. Adjuvant antiviral therapy cannot be recommended. On current data there is not sufficient evidence that the combination of steroids with antiviral drugs has a benefit for the patients. Even when not supported by randomized trials, adjuvant symptomatic therapy to protect the cornea and to avoid complications is recommended. There is no scientific evidence that physical therapy has any benefit but it should be taken into account because of psychological reasons. A benefit of acupuncture has not been proven. If eye closure remains incomplete as result of defective healing, one therapeutic option is lid loading of the upper eye lid. Moreover, in case of severe persistent palsy, several well-established microsurgical nerve and muscle plasty procedures are available.
Subject(s)
Bell Palsy/etiology , Bell Palsy/therapy , Acupuncture Therapy , Adrenal Cortex Hormones/therapeutic use , Antiviral Agents/therapeutic use , Bell Palsy/diagnosis , Diagnosis, Differential , Drug Therapy, Combination , Evidence-Based Medicine , Eyelids/surgery , Humans , Physical Therapy Modalities , Prognosis , Prostheses and ImplantsABSTRACT
BACKGROUND: The SARS-CoV-2 virus and its long-term consequences in adolescents have a global impact on upcoming medical issues. The aim of this study was to investigate the effects of a SARS-CoV-2 infection on cardiorespiratory parameters in young athletes. METHODS: In a cohort study involving repeated measurements during a six-month period, cardiorespiratory parameters were assessed in infected (SCoV) and non-infected (noSCoV) athletes. We evaluated handball players (17.2 ± 1.0 years) via performance diagnostics and a specific examination after a SARS-CoV-2 infection or without. RESULTS: We observed no significant differences between the two groups at the first visit. But between the first and second visit, the SCoV group's maximum power output was significantly lower than the noSCoV group's (- 48.3 ± 12.5; p ≤ 0.01 vs. - 15.0 ± 26.0 W; p = 0.09). At the second visit, lung diffusion capacity (DLCO/VA, %predicted) did not differ between groups (111.6 ± 11.5 vs. 116.1 ± 11.8%; p = 0.45). HR during comparative stress showed no group differences. The SCoV group's mean oxygen uptake during incremental exercise was lower (Two-way-ANOVA: 1912 vs. 2106 ml; p ≤ 0.01; mean difference: - 194 ml; 95% CI - 317 to - 71); we also noted a significantly lower stroke volume course during exercise (Two-way-ANAOVA: 147.5 vs. 169.5 ml; mean difference: - 22 ml; p ≤ 0.01; 95% CI - 34.2 to - 9.9). The probability of premature ventricular complexes after a SARS-CoV-2 infection yielded an odds ratio of 1.6 (95% CI 0.24-10.81). CONCLUSIONS: The physical performance of young athletes infected with SARS-CoV-2 was impaired. This decreased performance is probably due to cardiac and/or peripheral deconditioning. Studies with larger cohorts are needed to make more profound conclusions.
ABSTRACT
To study telomere length dynamics in hematopoietic cells with age, we analyzed the average length of telomere repeat sequences in diverse populations of nucleated blood cells. More than 500 individuals ranging in age from 0 to 90 yr, including 36 pairs of monozygous and dizygotic twins, were analyzed using quantitative fluorescence in situ hybridization and flow cytometry. Granulocytes and naive T cells showed a parallel biphasic decline in telomere length with age that most likely reflected accumulated cell divisions in the common precursors of both cell types: hematopoietic stem cells. Telomere loss was very rapid in the first year, and continued for more than eight decades at a 30-fold lower rate. Memory T cells also showed an initial rapid decline in telomere length with age. However, in contrast to naive T cells, this decline continued for several years, and in older individuals lymphocytes typically had shorter telomeres than did granulocytes. Our findings point to a dramatic decline in stem cell turnover in early childhood and support the notion that cell divisions in hematopoietic stem cells and T cells result in loss of telomeric DNA.
Subject(s)
Granulocytes/cytology , Hematopoietic Stem Cells/cytology , T-Lymphocyte Subsets/cytology , Telomere/genetics , Adolescent , Adult , Aged , Aged, 80 and over , Aging/genetics , Aging/pathology , Child , Child, Preschool , Female , Flow Cytometry , Humans , Immunologic Memory , In Situ Hybridization, Fluorescence , Infant , Infant, Newborn , Male , Middle Aged , T-Lymphocyte Subsets/immunology , Terminal Repeat Sequences , Twins, Dizygotic/genetics , Twins, Monozygotic/geneticsABSTRACT
Evidence-based supradisciplinary guideline that deals with the epidemiology, pathogenesis, symptoms, clinical and electrophysiological diagnosis, supplementary imaging investigations, differential diagnosis, conservative and surgical treatments, prognosis and course along with complications and revision surgery. The recommendations on investigation and treatment are based on a comprehensive literature search with critical evaluation and two consensus methods (expert group and Delphi technique) within the participating specialist societies. Besides this long version, a short version and a patient version can be viewed through the AWMF platform. The development of the guideline and the methodological foundations are documented in a method report. MAIN STATEMENTS: Apart from an accurate history and clinical neurological examination (including clinical tests), electrophysiological investigations (distal motor latency and sensory neurography) are particularly important. Radiography, MRI, high-resolution ultrasonography can be regarded as optional supplementary investigations. Among conservative treatment methods, treatment with a nocturnal splint and local infiltration of a corticosteroid preparation are effective. Oral steroids, splinting and ultrasound showed only short-term benefit. Surgical treatment is clearly superior to all other methods. Open and endoscopic procedures (when the endoscopic surgeon has sufficient experience) are equivalent. A routine epineurotomy and interfascicular neurolysis cannot be recommended. Early functional treatment postoperatively is important.
Subject(s)
Carpal Tunnel Syndrome , Adrenal Cortex Hormones/administration & dosage , Adrenal Cortex Hormones/therapeutic use , Adult , Aged , Algorithms , Anti-Inflammatory Agents, Non-Steroidal/administration & dosage , Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , Carpal Tunnel Syndrome/diagnosis , Carpal Tunnel Syndrome/diagnostic imaging , Carpal Tunnel Syndrome/epidemiology , Carpal Tunnel Syndrome/etiology , Carpal Tunnel Syndrome/surgery , Carpal Tunnel Syndrome/therapy , Complementary Therapies , Diagnosis, Differential , Electromyography , Electrophysiology , Endoscopy , Evidence-Based Medicine , Female , Germany , Humans , Incidence , Magnetic Resonance Imaging , Male , Meta-Analysis as Topic , Middle Aged , Practice Guidelines as Topic , Prognosis , Sensitivity and Specificity , Tomography, X-Ray Computed , Ultrasonography , YogaABSTRACT
Enterovirulent Escherichia coli are among the most important causes of acute diarrhea in developing as well as in developed countries. We have adapted classical PCR to detect these organisms in stool specimens to real-time PCR using the LightCycler (LC) SYBR Green format followed by melting curve analysis. With only two different cycling protocols we could detect enteropathogenic E. coli (EPEC) and verocytotoxin-producing E. coli (VTEC) (duplex assay for both Verotoxin 1 (VT1) and Verotoxin 2 (VT2)) in one run and enteroaggregative E. coli (EAEC), enteroinvasive E. coli (EIEC) and enterotoxigenic E. coli (ETEC) (duplex assay detecting both heat-stable enterotoxin (ST) and heat-labile enterotoxin (LT)) in another run. Using serial dilutions of control strains, the LC proved to be clearly more sensitive than conventional PCR for five out of seven investigated targets: VTEC (VT1 and VT2), ETEC (ST and LT) and EIEC. For EPEC and EAEC, LC and conventional PCR had identical sensitivities. With stool samples, we found an optimal agreement between LC-PCR and the conventional PCR when samples were tested in a 1:10 dilution. Only one specimen was discrepant, being repetitively positive for VT by LightCycler but not by conventional PCR. Given the significantly higher sensitivity of the LC-PCR for the VT target (up to a 10(-4) dilution factor by melting curve analysis and up to a 10(-6) dilution factor following gel electrophoresis), this is probably a false negative result by conventional PCR. We conclude that LightCycler PCR is more rapid, easier than and at least as sensitive as our conventional PCR for the detection of enterovirulent E. coli in stool specimens after culture on MacConkey.
Subject(s)
Diarrhea/microbiology , Escherichia coli Infections/diagnosis , Escherichia coli Infections/microbiology , Escherichia coli/genetics , Escherichia coli/isolation & purification , Polymerase Chain Reaction/methods , Bacterial Toxins/genetics , Bacteriological Techniques/statistics & numerical data , Base Sequence , DNA Primers/genetics , DNA, Bacterial/genetics , Enterotoxins/genetics , Escherichia coli/pathogenicity , Escherichia coli Proteins/genetics , Humans , Polymerase Chain Reaction/statistics & numerical data , Sensitivity and Specificity , Shiga Toxin 1/genetics , Shiga Toxin 2/genetics , VirulenceABSTRACT
The aim of this study was to investigate side-to-side differences of simultaneously measured middle cerebral artery (MCA) blood flow velocities during various hemisphere-specific tasks. Using a transcranial Doppler device, flow velocity changes of 24 healthy, right-handed subjects were monitored simultaneously in the left and right MCA during different hemisphere-specific tasks. Mean flow velocity (MFV) curves were averaged for each individual subject and task. Simultaneously, heart rate, blood pressure and end-tidal carbon dioxide (CO2) were measured in a subgroup of six subjects. When compared with the resting state, all stimuli produced significant (p < 0.001) bilateral MFV increases, ranging from 2.5-9.2%. A lateralization of MFV increases with a significantly (p < 0.001) more pronounced increase in MFV in the hemisphere contralateral to the performing band was observed both during simple sequential finger movements and a complex spatial task. During the complex spatial task, consistently higher MFV increases were observed in the right MCA (p < 0.001), regardless of the side of task performance. Recognition of pictorial material presented as part of a memory task, also resulted in a side-to-side difference of respective MFV increases (right > left, p < 0.001), whereas memorization did not. Whereas bilateral MFV elevations observed during stimulation with white noise were only discrete and not lateralized, exposure to overt speech produced significantly higher (p < 0.001) MFV increases in the left MCA. The time course of the MFV reaction showed a rapid increase with an initial maximum after 4-5 s. Heart rate, blood pressure, and end-tidal CO2 showed only subtle changes during the stimulation periods. In conclusion, the observed side-to-side differences of MFV reaction in the left and right MCA concur with current functional imaging data. Bilateral simultaneous repetitive transcranial Doppler monitoring is a sensitive method to detect cerebral perfusion asymmetries caused by hemisphere-specific activation, and thus may be helpful for noninvasive assessment of hemispheric dominance for language.
Subject(s)
Cerebrovascular Circulation/physiology , Dominance, Cerebral/physiology , Functional Laterality/physiology , Adult , Blood Flow Velocity , Female , Humans , MaleABSTRACT
OBJECTIVE: To determine the association between environmental tobacco smoke and middle ear disease in pre-school age children. DESIGN: A population-based case-control study with verification of disease history and exposure reporting in a subsample. SETTING AND PARTICIPANTS: Participants were identified through a population-base probability sample of 1320 first-grade students in 36 schools in Calgary, Alberta. The parents of 625 children meeting case (n = 227) or control (n = 398) definitions were interviewed by telephone for their children's exposure history. The adequacy of exposure and disease measures was assessed using hair continue measurements, home visits, and physician medical records for 92 children. MAIN OUTCOME MEASURES AND RESULTS: A history of middle ear disease was found in 23.9% of the sample. Relationships were found between middle ear disease and 2 or more household smokers (crude odds ratio) [OR], 1.85; 95% confidence interval [CI], 1.15-2.97), 10 or more cigarettes smoked by the mother per day (crude OR, 1.68; 95% CI, 1.12-2.52), and 10 or more cigarettes smoked in total in the household per day (crude OR, 1.40; 95% CI, 0.98-2.00) during the first 3 years of life. In logistic regression modeling these effects persisted after adjusting for child care (type, age started, duration, and group size), infant feeding (type and duration), socioeconomic status, maternal education level, number of prenatal ultrasonographic examinations, and health services use. The mean current hair cotinine levels were higher for children living in homes with 1 or more smokers vs no smokers (0.51 vs 0.31 ng/mg, P = .01). There was fair agreement (75.3%) between physician medical records and parental report of disease history, but some misclassification bias toward the null hypothesis likely. CONCLUSION: Environmental tobacco smoke is an important risk factor for middle ear disease in urban preschool-age children, even in a relatively affluent population.
Subject(s)
Ear, Middle , Tobacco Smoke Pollution/adverse effects , Case-Control Studies , Child , Child, Preschool , Cotinine/analysis , Ear Diseases/etiology , Female , Hair/chemistry , Humans , Infant , Logistic Models , Male , Odds Ratio , Risk FactorsABSTRACT
The decay and recovery of stapedial reflex amplitude was investigated in 19 patients with myasthenia gravis and 30 control subjects. In 9 untreated patients the amplitude was reduced to less than 10% of the initial amplitude following continuous stimulation for 120 s, whereas the maximum decay in the control subjects was only 50%. In the group of treated patients the reflex decay showed individual variations. The rate of recovery after prolonged stimulation (5 min) was slower in the patient group, especially within the first 30 s of recovery. With increasing age, the rate of decay rose in the patient group as well as in the control group. The technical parameters necessary for obtaining information of clear diagnostic value are indicated, with which it was shown that the continuous prolonged stimulation of the stapedial muscle is a practical and valid method for the evaluation of patients with myasthenia gravis.
Subject(s)
Muscles/physiopathology , Myasthenia Gravis/diagnosis , Reflex, Acoustic , Stapedius/physiopathology , Adolescent , Adult , Aged , Female , Humans , Male , Middle Aged , Myasthenia Gravis/physiopathologyABSTRACT
The latencies and amplitudes of responses evoked by magnetic brain stimulation (magnetic evoked potentials, MEP) in the first dorsal interosseus and the anterior tibial (TA) muscles were investigated in 15 patients with psychogenic limb weakness and in 50 patients with limb weakness due to established organic central nervous system disease. Of the patients with psychogenic limb weakness, 3 presented with upper limb monopareses, 2 with lower limb monoparesis, 4 with hemipareses, 4 with parapareses and 2 with paraparesis. All patients with psychogenic weakness had MEP in arm and leg muscles with latencies within the normal range. MEP amplitudes were also normal except for 1 patient in whom the response amplitude in the TA of the plegic limb was reduced. In patients with limb weakness due to established organic disease, MEP were frequently but not invariably abnormal. In patients with plegic (i.e. completely paretic, MRC grade 0) muscles due to organic disease, MEP always were clearly abnormal. Normal MEP were sometimes elicited from paretic muscles, more commonly in association with cerebral hemisphere lesions than with spinal lesions. We conclude that psychogenic limb weakness is associated with normal MEP. However, normal MEP in mildly paretic muscles do not definitely exclude organic pathology.
Subject(s)
Brain/physiology , Magnetics , Muscles/physiopathology , Somatoform Disorders/physiopathology , Adolescent , Adult , Aged , Evoked Potentials/physiology , Extremities/physiopathology , Female , Humans , Male , Middle Aged , Neuromuscular Diseases/physiopathology , Reaction Time/physiologyABSTRACT
The effects of the competitive N-methyl-D-aspartate (NMDA) receptor antagonists, CGP37849 (3 or 6 mg/kg i.p.) and its ethyl ester CGP39551 (5 or 15 mg/kg i.p.) and of the non-competitive NMDA receptor antagonist, dizocilpine (0.16 mg/kg; i.p.) on acquisition by rats of different spatial orientation tasks in an 8-arm radial maze were evaluated. Neither of the CGP compounds influenced locomotor activity during spontaneous alternation, only dizocilpine increased the number of arm entries (locomotion). Preferred angles between consecutive arm entries were changed by the high doses of CGP37849 (6 mg/kg), CGP39551 (15 mg/kg) and dizocilpine (0.16 mg/kg). The high doses of both CGP compounds as well as dizocilpine produced impairments in the acquisition of an egocentric orientation task and an allocentric reversal task indicated by an increased number of arm entries and re-entries. Such amnesic effects did not occur after administration of low doses of CGP37849 (3 mg/kg) and CGP39551 (5 mg/kg), doses which are sufficient to produce anticonvulsant and anticataleptic effects. In contrast, the non-competitive NMDA receptor antagonist, dizocilpine, produced amnesic effects over the entire behaviourally effective dose range.
Subject(s)
2-Amino-5-phosphonovalerate/analogs & derivatives , Behavior, Animal/drug effects , Dizocilpine Maleate/pharmacology , Learning/drug effects , Receptors, N-Methyl-D-Aspartate/antagonists & inhibitors , 2-Amino-5-phosphonovalerate/pharmacology , Animals , Male , Memory/drug effects , Motor Activity/drug effects , Orientation/drug effects , Rats , Rats, Inbred Strains , Receptors, N-Methyl-D-Aspartate/physiologyABSTRACT
OBJECTIVES: The aim of this study was to evaluate if the type of surface electrode (disposable/non-disposable, fixed/variable inter-electrode distances, different surface structure and size of recording area) influences the compound muscle action potential (CMAP) values of baseline-to-peak and peak-to-peak amplitude and corresponding areas and duration. METHODS: We investigated a total of 72 CMAPs of the abductor digiti minimi and the tibial anterior muscle of 18 healthy persons using 7 different types of electrodes in each muscle. RESULTS: There was no significant difference of CMAP values between the electrodes which had a variable inter-electrode distance. A significant difference of all CMAP values was observed when these electrodes were compared with a bar-electrode with a fixed inter-electrode distance (P<0.001). There was no correlation between recording area of the electrodes and the absolute CMAP values. Only the differences of CMAP values between each electrode and a defined electrode in each subject revealed a significant correlation between the size of recording area and these differences of CMAP values. CONCLUSION: To avoid false results in motor neurography only electrodes with variable distances between the recording pairs should be used. Using those electrodes and following standardized measuring conditions, CMAP values can be compared even if they are measured in different laboratories and at different occasions.
Subject(s)
Action Potentials/physiology , Electrodes , Muscles/physiology , Adult , Electromyography , HumansABSTRACT
The correlation between brain activity and cerebral blood flow velocities during brief bursts of generalized spike and wave activity was analysed by simultaneous registration of the EEG and the intracranial flow patterns. The flow patterns of the middle cerebral artery were continuously recorded by means of transcranial Doppler ultrasonography using a specially developed monitoring system. A total of 25 bursts was investigated in 3 patients with spontaneous occurrence of generalized 3 Hz spike and wave activity and normal background EEG. Characteristic changes of the flow patterns were found in all cases: 3.41 +/- 0.98 s (n = 25) after the beginning of generalized spike and wave patterns, the flow velocity decreased by 25.84 +/- 10.45% (n = 25) below the 'preictal' flow velocity level. The period of flow velocity changes lasted several times longer than the phase of spike and wave activity.