Counterpoint: Conventional Fluoroscopy-Guided Selective Cervical Nerve Root Block-A Safe, Effective, and Efficient Modality in the Hands of an Experienced Proceduralist.

BACKGROUND AND PURPOSE: The conventional fluoroscopy-guided (CF) selective cervical nerve root block (SCNRB) is being used commonly as a treatment for cervical radicular pain as well as a diagnostic tool. This study aimed to identify any major complications and determine the safety and clinical utility of CF-SCNRB performed in a university hospital and associated outpatient clinics. MATERIALS AND METHODS: Two-hundred fifty-four conventional fluoroscopy-guided selective cervical nerve root blocks were retrospectively identified from 2011 to 2018 using a radiology report search tool. Each procedure was performed by an experienced neuroradiologist performing spinal injections on a full-time basis in clinical practice. A 10-point pain scale was used for pre- and postprocedural pain-level assessment. Successful conventional, fluoroscopy-guided, selective cervical nerve root block was defined as a patient-reported pain scale reduction of at least 50% and/or alleviation of numbness or paresthesia at ≥2 weeks postinjection. All clinically important immediate and delayed complications were also recorded. RESULTS: Two-hundred fifty-four conventional fluoroscopy-guided selective cervical nerve root blocks were performed via an anterolateral approach with an average fluoroscopy time of 24.3 seconds for all cases. There were no aborted procedures and no major or permanent complications. There were 14 minor complications; 12 of these were periprocedural and resolved by the 2-week follow-up visit. One-hundred eighty-five patients (75.2%) reported pain improvement of >50% from baseline at 15 minutes postinjection. Overall, 172 patients (67.7%) reported >50% pain scale reduction or alleviation from paresthesia at least 2 weeks postinjection. CONCLUSIONS: Conventional fluoroscopy-guided selective cervical nerve root block is an efficacious, efficient, and safe outpatient procedure when performed by a skilled and experienced proceduralist.

Dense arrays of cobalt nanorods as rare-earth free permanent magnets.

We demonstrate in this paper the feasibility to elaborate rare-earth free permanent magnets based on cobalt nanorods assemblies with energy product (BH)max exceeding 150 kJ m(-3). The cobalt rods were prepared by the polyol process and assembled from wet suspensions under a magnetic field. Magnetization loops of dense assemblies with remanence to a saturation of 0.99 and squareness of 0.96 were measured. The almost perfect M(H) loop squareness together with electron microscopy and small angle neutron scattering demonstrate the excellent alignment of the rods within the assemblies. The magnetic volume fraction was carefully measured by coupling magnetic and thermogravimetric analysis and found in the range from 45 to 55%, depending on the rod diameter and the alignment procedure. This allowed a quantitative assessment of the (BH)max values. The highest (BH)max of 165 kJ m(-3) was obtained for a sample combining a high magnetic volume fraction and a very large M(H) loop squareness. This study shows that this bottom-up approach is very promising to get new hard magnetic materials that can compete in the permanent magnet panorama and fill the gap between the ferrites and the NdFeB magnets.

Dual antiferromagnetic coupling at La0.67Sr0.33MnO3/SrRuO3 interfaces.

We have studied the magnetic hysteresis cycle of La0.67Sr0.33MnO3/SrRuO3 antiferromagnetically coupled bilayers, by magnetometry and polarized neutron reflectometry. A positive exchange bias as well as an unusual asymmetry are observed on the magnetic reversal process of the La0.67Sr0.33MnO3 layer. Through an extended Stoner-Wohlfarth model comprising the magnetic anisotropy of both layers, we give experimental evidence that this asymmetry originates from two different but well-defined antiferromagnetic coupling strengths at the interface between the two magnetic oxides. The possible origin of this dual coupling is discussed in view of our experimental results.

Poststreptococcal dystonia with bilateral striatal enlargement: MR imaging and spectroscopic findings.

Isolated bilateral striatal necrosis is an abnormality of the basal ganglia associated with acute dystonia in children. This report describes the development of dystonic movements in a 7-year-old male patient 2 weeks after streptococcal pharyngitis.

Mechanisms of exchange bias with multiferroic BiFeO3 epitaxial thin films.

We have combined neutron scattering and piezoresponse force microscopy to show that the exchange field in CoFeB/BiFeO_{3} heterostructures scales with the inverse of the ferroelectric and antiferromagnetic domain size of the BiFeO3 films, as expected from Malozemoff's model of exchange bias extended to multiferroics. Accordingly, polarized neutron reflectometry reveals the presence of uncompensated spins in the BiFeO3 film at the interface with CoFeB. In view of these results, we discuss possible strategies to switch the magnetization of a ferromagnet by an electric field using BiFeO3.

Biaxial strain in the hexagonal plane of MnAs thin films: the key to stabilize ferromagnetism to higher temperature.

The alpha-beta magnetostructural phase transition in MnAs/GaAs(111) epilayers is investigated by elastic neutron scattering. The in-plane parameter of MnAs remains almost constant with temperature from 100 to 420 K, following the thermal evolution of the GaAs substrate. This induces a temperature dependent biaxial strain that is responsible for an alpha-beta phase coexistence and, more importantly, for the stabilization of the ferromagnetic alpha phase at a higher temperature than in the bulk. We explain the premature appearance of the beta phase at 275 K and the persistence of the ferromagnetic alpha phase up to 350 K with thermodynamical arguments based on the MnAs phase diagram. It results that the biaxial strain in the hexagonal plane is the key parameter to extend the ferromagnetic phase well over room temperature.

Magnetic filaments in resistive manganites.

The magnetic phase separation in single crystals of the Pr0.67Ca0.33MnO3 manganites is studied using polarized small angle neutron scattering. The measured spectra give a fractal dimension consistent with a configuration in ferromagnetic filaments of nanometric diameter. We argue here that localized charge carriers hop in a random walk fashion mediating a ferromagnetic "hopping exchange" which coexists with superexchange to create the filamentary phase separation. The arguments for this physical picture are validated by Monte Carlo simulations, where magnetism and transport are treated in a self-consistent manner.

Individual domain wall resistance in submicron ferromagnetic structures.

The resistance generated by individual domain walls is measured in a FePd nanostructure. Combining transport and magnetic imaging measurements, the intrinsic domain wall resistance is quantified. It is found positive and of a magnitude consistent with that predicted by models based on spin scattering effects within the walls. This magnetoresistance at a nanometer scale allows a direct counting of the number of walls inside the nanostructure. The effect is then used to measure changes in the magnetic configuration of submicron stripes under application of a magnetic field.

Flow-induced pressure differentially regulates endothelin-1, urotensin II, adrenomedullin, and relaxin in pulmonary vascular endothelium.

We hypothesized that increased pulmonary vascular pressure--one of the characteristics of congestive heart failure--directly regulates pulmonary endothelial vasoconstrictors (endothelin-1, urotensin II) and vasodilators (adrenomedullin, relaxin). To this end, we subjected pulmonary artery endothelial cells in a novel flow-chamber model to different shear stresses (17, 29, and 46 dyn/cm(2)) at low and elevated levels of downstream pressure (10 and 30 mm Hg). Application of elevated pressure over 16 h increased gene expression and peptide secretion of endothelin-1 at all shear levels, whereas secretion of adrenomedullin rose via decreased expression of its clearance receptor. In contrast, preprourotensin II mRNA and urotensin II peptide decreased in response to elevated pressure, and relaxin remained unaffected. This is the first study to identify pressure as key regulator of mediator synthesis by pulmonary vascular endothelium. Pressure-induced mediator regulation may represent an early event in the development of secondary pulmonary hypertension.

Anisotropy of domain wall resistance

The resistive effect of domain walls in FePd films with perpendicular anisotropy was studied experimentally as a function of field and temperature. The films were grown directly on MgO substrates, which induces an unusual virgin magnetic configuration composed of 60 nm wide parallel stripe domains. This allowed us to carry out the first measurements of the anisotropy of domain wall resistivity in the two configurations of current perpendicular and parallel to the walls. At 18 K, we find 8.2% and 1.3% for the domain wall magnetoresistance normalized to the wall width (8 nm) in these two respective configurations. These values are consistent with the predictions of Levy and Zhang.

Successful treatment of chronic hand eczema with oral 9-cis-retinoic acid.

BACKGROUND: 9-cis-Retinoic acid (9-cis-RA) has a particular pattern of binding and activating retinoid receptors. Treatment of chronic hand eczema is often refractory to conventional treatment. OBJECTIVE: Evaluation of oral 9-cis-RA therapy in chronic hand eczema in a pilot study. METHODS: Thirty-eight patients with refractory chronic hand eczema were treated in an exploratory open-label study with oral 9-cis-RA. RESULTS: Twenty-one (55%) showed a very good response, 13 (34%) a good response, 2 (5.5%) a moderate response and 2 (5.5%) no response. Side effects were mild. CONCLUSION: 9-cis-RA is a valuable drug when given at low doses to patients with chronic hand eczema.

Efficacy of oral low-dose tretinoin (all-trans-retinoic acid) in lichen planus.

BACKGROUND: Retinoids were shown to be effective in the treatment of both oral and cutaneous forms of lichen planus. OBJECTIVE: Confirm the beneficial effect of low doses of oral tretinoin in lichen planus. METHODS: Eighteen patients with lichen planus were treated in an open study for up to 19 months. Efficacy and safety data were recorded. RESULTS: Complete remission was observed in 13 (72%) and marked improvement in 4 (22%) out of 18 patients. Six patients showed moderate and 12 had no side effects. CONCLUSION: Tretinoin is a valuable drug when given at low doses to patients with lichen planus who failed to respond to other therapies.

Oral 9-cis-retinoic acid versus 13-cis-retinoic acid in acne therapy.

BACKGROUND: 9-cis-Retinoic acid (9-cis-RA) is as active as 13-cis-retinoic acid (13-cis-RA) in inhibiting the proliferation of cultured human sebocytes and in reducing the size of sebaceous glands of hamsters. OBJECTIVE: Evaluate the anti-acne effect of 9-cis-RA compared to that of 13-cis-RA in a pilot study. METHODS: Four young male patients with acne were treated in an open study consecutively with 9-cis-RA and 13-cis-RA given at similar doses. RESULTS: No beneficial effects were observed with 9-cis-RA in any of the patients whereas all responded favorably to 13-cis-RA. CONCLUSION: For the two retinoids tested, the anti-acne effect correlates with the sebosuppressive effect in humans.

All about ichthyosis.

From "alligator people" to "porcupine boys," the ichthyoses have been a distinctly recognizable entity for thousands of years. Recent improvements in biochemical and genetic research have allowed more scientific delineation of this class of diseases. This article covers the latest in pathophysiology, the major classes of ichthyoses, many of the newer minor ones, prenatal diagnosis, and treatment options.

Ribonucleosides as minor milk constituents.

Ribonucleosides are minor milk constituents and show a typical pattern which is assumed to be species-specific. As well as the unmodified components adenosine, cytidine, guanosine, inosine, and uridine, modified compounds such as Nl-methyladenosine and N6-carbamoylthreonyladenosine--products of the transfer RNA catabolism--have been identified and quantified in individual and bulk herd (race: German black pied) milk samples throughout a whole lactation period. The results of our longitudinal study have shown that--with the exception of the colostral phase--the levels of these minor constituents vary only slightly throughout lactation. These findings imply that ribonucleosides are useful for characterizing milk of different species and technological treatment. Ribonucleosides were determined and balanced, for example, in the course of the churning process, showing that the pattern of these minor milk constituents is useful as a "fingerprint" that allows differentiation between the three butter types defined in the German Federal Butter Ordinance.

Morphological characterization of carotid artery stenoses by ultrasound duplex scanning.

Ulcerations and intraplaque hemorrhages are thought to play an important role in the development of neurological deficits in carotid artery stenoses. To assess the ability of duplex scanning to predict plaque morphology we compared different sonographic criteria (plaque border, plaque density, plaque structure) with the morphological findings in 169 consecutive carotid endarterectomies (144 cases with diameter reduction greater than 50%). Two percent of the sonograms were inadequate, and 20% showed poor image quality. Regular plaque borders revealed a smooth or at most minimally ulcerated surface in 92%. Grossly ulcerated stenoses, however, were only found in 27% of the irregular plaques. Moreover, the plaque border was nonvisible in 35% of all cases. Simple, fibro-atheromatous plaques were found to be echogenic in 72% and echolucency was present in 80% of the stenoses with relevant intraplaque hemorrhage. In conclusion, duplex scanning proved to be capable of detecting smooth, fibro-atheromatous stenoses with high accuracy. Ulcerations, however, cannot be predicted reliably, and intraplaque hemorrhage cannot be differentiated from atheromatous debris.

[Determination of the degree of stenosis in carotid artery stenoses: ultrasound and i.v. DSA in comparison to surgical findings]. / Bestimmung des Stenosierungsgrades bei Karotisstenosen: Ultraschall und i.v. DSA im Vergleich zum Operationsbefund.

The specimens from 116 consecutive carotid thrombendarterectomies were taken as "gold standard" to evaluate the accuracy of ultrasound methods (duplex scanning + extra-/transcranial Doppler sonography) and intravenous digital subtraction angiography (i.v. DSA) in carotid artery stenoses. In 65 cases, in which the specimens could be gauged reliably, sonography estimated the degree of stenosis in 85% within a range of +/- 10%, in 97% within +/- 20% i.v. DSA was accurate in 52 respectively in 94%. High-grade stenoses were correctly assessed by ultrasound in 90%, by i.v. DSA in 64%. Sonography identified 4/10 kinkings and coilings of the carotid artery, i.v. DSA 9/10. Current available ultrasound methods enable estimation of the diameter reduction of carotid artery stenoses with low deviations. I.v. DSA seems to be less reliable, but can be used favourably as a complementary method to sonography.

[Malignant atrophic papulosis (Degos' syndrome) in a suckling infant]. / Maligne atrophisierende Papulose (Degos-Syndrom) bei einem Säugling.

The clinical and histological diagnosis of Degos' syndrome could be made in a 8-month-old infant with scarring skin lesions. Some weeks later the baby developed severe intestinal symptoms and died from perforations of multiple necrotic lesions of the small bowel. Autopsy revealed in addition to the skin and gut lesions a haemorrhagic cortical infarction of the brain and fibrotic areas in the myocardium. In all these lesions characteristic stenotic endovascular proliferations were seen. Malignant atrophic papulosis is an extremely rare disease in infancy (our patient is the fifth reported case) with a well defined clinical picture, characteristic histological appearance of obliterating vasculitis, but unknown aetiology.