A clinically validated, broadly active, oral viral superinfection therapy could mitigate symptoms in early-stage COVID-19 patients

More than 200 viruses infect humans but drugs are available for fewer than ten. To narrow the gap between 'bugs and drugs', a paradigm shift is required. The "one drug, one bug" approach should be supplemented by the "one drug, multiple bugs" strategy such that the host is targeted rather than the virus. The revolutionary viral superinfection therapy (SIT) activates the antiviral interferon gene natural defense system of host cells from within by an attenuated infectious bursal disease virus (IBDV) that releases its double-stranded RNA (dsRNA) cargo inside the cells. An attenuated IBDV vaccine strain has resolved hepatitis A virus infection (HAV) in marmoset monkeys and hepatitis B and C virus infections (HBV/HCV) in 42 patients with acute HBV or HCV. SIT was also safe and effective in four hepatically decompensated, chronically infected HBV and HCV patients. The proof-of-principle of SIT was demonstrated first in a 43-year-old male patient with COVID-19. Three doses of IBDV (3x106 IU) alleviated most of his COVID-19 symptoms, even the sense of smell returned within a week. Two additional COVID-19 patients responded similarly to oral treatment with IBDV. Furthermore, a severe herpes zoster ophthalmicus with orbital edema was healed within few days by combination of acyclovir and 7 doses IBDV (7x106 IU). IBDV is simple to manufacture and will be affordable even in resource limited settings. Acid resistant IBDV can be orally administered in an outpatient setting providing the greatest ease of dosing and the highest chance of patient compliance. Under an Emergency Use Authorization, the broad-based IBDV drug candidate could be tested immediately in clinical trials and rapidly distributed to millions of early-stage patients with COVID-19. The German Paul Ehrlich Institute supports such a phase I safety study for persons acutely infected with SARS‑CoV-2. An expert team of the US National Institutes of Health-sponsored ACTIV public-private partnership came to the conclusion that the IBDV drug candidate shows merit as a potential treatment for COVID-19 and an FDA approved clinical trial is in the pipelines in Los Angeles.

Skin sodium measured with ²³Na MRI at 7.0 T

Skin sodium (Na(+) ) storage, as a physiologically important regulatory mechanism for blood pressure, volume regulation and, indeed, survival, has recently been rediscovered. This has prompted the development of MRI methods to assess Na(+) storage in humans ((23) Na MRI) at 3.0 T. This work examines the feasibility of high in-plane spatial resolution (23) Na MRI in skin at 7.0 T. A two-channel transceiver radiofrequency (RF) coil array tailored for skin MRI at 7.0 T (f = 78.5 MHz) is proposed. Specific absorption rate (SAR) simulations and a thorough assessment of RF power deposition were performed to meet the safety requirements. Human skin was examined in an in vivo feasibility study using two-dimensional gradient echo imaging. Normal male adult volunteers (n = 17; mean ± standard deviation, 46 ± 18 years; range, 20-79 years) were investigated. Transverse slices of the calf were imaged with (23) Na MRI using a high in-plane resolution of 0.9 × 0.9 mm(2) . Skin Na(+) content was determined using external agarose standards covering a physiological range of Na(+) concentrations. To assess the intra-subject reproducibility, each volunteer was examined three to five times with each session including a 5-min walk and repositioning/preparation of the subject. The age dependence of skin Na(+) content was investigated. The (23) Na RF coil provides improved sensitivity within a range of 1 cm from its surface versus a volume RF coil which facilitates high in-plane spatial resolution imaging of human skin. Intra-subject variability of human skin Na(+) content in the volunteer population was <10.3%. An age-dependent increase in skin Na(+) content was observed (r = 0.78). The assignment of Na(+) stores with (23) Na MRI techniques could be improved at 7.0 T compared with current 3.0 T technology. The benefits of such improvements may have the potential to aid basic research and clinical applications designed to unlock questions regarding the Na(+) balance and Na(+) storage function of skin.

Modular 32-channel transceiver coil array for cardiac MRI at 7.0T

PURPOSE

To design and evaluate a modular transceiver coil array with 32 independent channels for cardiac MRI at 7.0T.

METHODS

The modular coil array comprises eight independent building blocks, each containing four transceiver loop elements. Numerical simulations were used for B1 (+) field homogenization and radiofrequency (RF) safety validation. RF characteristics were examined in a phantom study. The array's suitability for accelerated high spatial resolution two-dimensional (2D) FLASH CINE imaging of the heart was examined in a volunteer study.

RESULTS

Transmission field adjustments and RF characteristics were found to be suitable for the volunteer study. The signal-to-noise intrinsic to 7.0T together with the coil performance afforded a spatial resolution of 1.1 × 1.1 × 2.5 mm(3) for 2D CINE FLASH MRI, which is by a factor of 6 superior to standardized CINE protocols used in clinical practice at 1.5T. The 32-channel transceiver array supports one-dimensional acceleration factors of up to R = 4 without impairing image quality significantly.

CONCLUSION

The modular 32-channel transceiver cardiac array supports accelerated and high spatial resolution cardiac MRI. The array is compatible with multichannel transmission and provides a technological basis for future clinical assessment of parallel transmission techniques at 7.0T.

Detailing radio frequency heating induced by coronary stents: a 7.0 Tesla magnetic resonance study

The sensitivity gain of ultrahigh field Magnetic Resonance (UHF-MR) holds the promise to enhance spatial and temporal resolution. Such improvements could be beneficial for cardiovascular MR. However, intracoronary stents used for treatment of coronary artery disease are currently considered to be contra-indications for UHF-MR. The antenna effect induced by a stent together with RF wavelength shortening could increase local radiofrequency (RF) power deposition at 7.0 T and bears the potential to induce local heating, which might cause tissue damage. Realizing these constraints, this work examines RF heating effects of stents using electro-magnetic field (EMF) simulations and phantoms with properties that mimic myocardium. For this purpose, RF power deposition that exceeds the clinical limits was induced by a dedicated birdcage coil. Fiber optic probes and MR thermometry were applied for temperature monitoring using agarose phantoms containing copper tubes or coronary stents. The results demonstrate an agreement between RF heating induced temperature changes derived from EMF simulations versus MR thermometry. The birdcage coil tailored for RF heating was capable of irradiating power exceeding the specific-absorption rate (SAR) limits defined by the IEC guidelines by a factor of three. This setup afforded RF induced temperature changes up to +27 K in a reference phantom. The maximum extra temperature increase, induced by a copper tube or a coronary stent was less than 3 K. The coronary stents examined showed an RF heating behavior similar to a copper tube. Our results suggest that, if IEC guidelines for local/global SAR are followed, the extra RF heating induced in myocardial tissue by stents may not be significant versus the baseline heating induced by the energy deposited by a tailored cardiac transmit RF coil at 7.0 T, and may be smaller if not insignificant than the extra RF heating observed under the circumstances used in this study.

Two-dimensional sixteen channel transmit/receive coil array for cardiac MRI at 7.0 T: design, evaluation, and application

PURPOSE

To design, evaluate, and apply a 2D 16-channel transmit/receive (TX/RX) coil array tailored for cardiac magnetic resonance imaging (MRI) at 7.0 T.

MATERIALS AND METHODS

The cardiac coil array consists of two sections each using eight elements arranged in a 2 × 4 array. Radiofrequency (RF) safety was validated by specific absorption rate (SAR) simulations. Cardiac imaging was performed using 2D CINE FLASH imaging, T 2 mapping, and fat-water separation imaging. The characteristics of the coil array were analyzed including parallel imaging performance, left ventricular chamber quantification, and overall image quality.

RESULTS

RF characteristics were found to be appropriate for all subjects included in the study. The SAR values derived from the simulations fall well within the limits of legal guidelines. The baseline signal-to-noise ratio (SNR) advantage at 7.0 T was put to use to acquire 2D CINE images of the heart with a very high spatial resolution of (1 × 1 × 4) mm(3) . The proposed coil array supports 1D acceleration factors of up to R = 4 without significantly impairing image quality.

CONCLUSION

The 16-channel TX/RX coil has the capability to acquire high contrast and high spatial resolution images of the heart at 7.0 T.

(23)Na magnetic resonance imaging of tissue sodium

Hypertension is linked to disturbed total-body sodium (Na(+)) regulation; however, measuring Na(+) disposition in the body is difficult. We implemented (23)Na magnetic resonance spectroscopy ((23)Na-MR) and imaging technique ((23)Na-MRI) at 9.4T for animals and 3T for humans to quantify Na(+) content in skeletal muscle and skin. We compared (23)Na-MRI data with actual tissue Na(+) content measured by chemical analysis in animal and human tissue. We then quantified tissue Na(+) content in normal humans and in patients with primary aldosteronism. We found a 29% increase in muscle Na(+) content in patients with aldosteronism compared with normal women and men. This tissue Na(+) was mobilized after successful treatment without accompanying weight loss. We suggest that, after further refinements, this tool could facilitate understanding the relationships between Na(+) accumulation and hypertension. Furthermore, with additional technical advances, a future clinical use may be possible.

Design, evaluation and application of an eight channel transmit/receive coil array for cardiac MRI at 7.0 T

The objective of this work is to design, examine and apply an eight channel transmit/receive coil array tailored for cardiac magnetic resonance imaging at 7.0 T that provides image quality suitable for clinical use, patient comfort, and ease of use. The cardiac coil array was designed to consist of a planar posterior section and a modestly curved anterior section. For radio frequency (RF) safety validation, numerical computations of the electromagnetic field (EMF) and the specific absorption rate (SAR) distribution were conducted. In vivo cardiac imaging was performed using a 2D CINE FLASH technique. For signal-to-noise ratio (SNR) assessment reconstructed images were scaled in SNR units. The parallel imaging capabilities of the coil were examined using GRAPPA and SENSE reconstruction with reduction factors of up to R=4. The assessment of the RF characteristics yielded a maximum noise correlation of 0.33. The baseline SNR advantage at 7.0 T was put to use to acquire 2D CINE images of the heart with a spatial resolution of 1 mm × 1 mm × 4 mm. The coil array supports 1D acceleration factors of up to R=3 without impairing image quality significantly. For un-accelerated 2D CINE FLASH acquisitions the results revealed an SNR of approximately 140 for the left ventricular blood pool. Blood/myocardium contrast was found to be approximately 90 for un-accelerated 2D CINE FLASH acquisitions. The proposed 8 channel cardiac transceiver surface coil has the capability to acquire high contrast, high spatial and temporal resolution in vivo images of the heart at 7.0 T.

Development and evaluation of a small and mobile Magneto Alert Sensor (MALSE) to support safety requirements for magnetic resonance imaging

OBJECTIVE

The purpose of this study is to (i) design a small and mobile Magnetic field ALert SEnsor (MALSE), (ii) to carefully evaluate its sensors to their consistency of activation/deactivation and sensitivity to magnetic fields, and (iii) to demonstrate the applicability of MALSE in 1.5 T, 3.0 T and 7.0 T MR fringe field environments.

METHODS

MALSE comprises a set of reed sensors, which activate in response to their exposure to a magnetic field. The activation/deactivation of reed sensors was examined by moving them in/out of the fringe field generated by 7TMR.

RESULTS

The consistency with which individual reed sensors would activate at the same field strength was found to be 100% for the setup used. All of the reed switches investigated required a substantial drop in ambient magnetic field strength before they deactivated.

CONCLUSIONS

MALSE is a simple concept for alerting MRI staff to a ferromagnetic object being brought into fringe magnetic fields which exceeds MALSEs activation magnetic field. MALSE can easily be attached to ferromagnetic objects within the vicinity of a scanner, thus creating a barrier for hazardous situations induced by ferromagnetic parts which should not enter the vicinity of an MR-system to occur.

Acoustic cardiac triggering: a practical solution for synchronization and gating of cardiovascular magnetic resonance at 7 Tesla

BACKGROUND

To demonstrate the applicability of acoustic cardiac triggering (ACT) for imaging of the heart at ultrahigh magnetic fields (7.0 T) by comparing phonocardiogram, conventional vector electrocardiogram (ECG) and traditional pulse oximetry (POX) triggered 2D CINE acquisitions together with (i) a qualitative image quality analysis, (ii) an assessment of the left ventricular function parameter and (iii) an examination of trigger reliability and trigger detection variance derived from the signal waveforms.

RESULTS

ECG was susceptible to severe distortions at 7.0 T. POX and ACT provided waveforms free of interferences from electromagnetic fields or from magneto-hydrodynamic effects. Frequent R-wave mis-registration occurred in ECG-triggered acquisitions with a failure rate of up to 30% resulting in cardiac motion induced artifacts. ACT and POX triggering produced images free of cardiac motion artefacts. ECG showed a severe jitter in the R-wave detection. POX also showed a trigger jitter of approximately Δt = 72 ms which is equivalent to two cardiac phases. ACT showed a jitter of approximately Δt = 5 ms only. ECG waveforms revealed a standard deviation for the cardiac trigger offset larger than that observed for ACT or POX waveforms.Image quality assessment showed that ACT substantially improved image quality as compared to ECG (image quality score at end-diastole: ECG = 1.7 ± 0.5, ACT = 2.4 ± 0.5, p = 0.04) while the comparison between ECG vs. POX gated acquisitions showed no significant differences in image quality (image quality score: ECG = 1.7 ± 0.5, POX = 2.0 ± 0.5, p = 0.34).

CONCLUSIONS

The applicability of acoustic triggering for cardiac CINE imaging at 7.0 T was demonstrated. ACT's trigger reliability and fidelity are superior to that of ECG and POX. ACT promises to be beneficial for cardiovascular magnetic resonance at ultra-high field strengths including 7.0 T.

Degenerate mode band-pass birdcage coil for accelerated parallel excitation

An eight-rung, 3T degenerate birdcage coil (DBC) was constructed and evaluated for accelerated parallel excitation of the head with eight independent excitation channels. Two mode configurations were tested. In the first, each of the eight loops formed by the birdcage was individually excited, producing an excitation pattern similar to a loop coil array. In the second configuration a Butler matrix transformed this "loop coil" basis set into a basis set representing the orthogonal modes of the birdcage coil. In this case the rung currents vary sinusoidally around the coil and only four of the eight modes have significant excitation capability (the other four produce anticircularly polarized (ACP) fields). The lowest useful mode produces the familiar uniform B(1) field pattern, and the higher-order modes produce center magnitude nulls and azimuthal phase variations. The measured magnitude and phase excitation profiles of the individual modes were used to generate one-, four-, six-, and eightfold-accelerated spatially tailored RF excitations with 2D and 3D k-space excitation trajectories. Transmit accelerations of up to six-fold were possible with acceptable levels of spatial artifact. The orthogonal basis set provided by the Butler matrix was found to be advantageous when an orthogonal subset of these modes was used to mitigate B(1) transmit inhomogeneities using parallel excitation.

On the heating of linear conductive structures as guide wires and catheters in interventional MRI

The interest in performing vascular interventions under magnetic resonance (MR) guidance has initiated the evaluation of the potential hazard of long conductive wires and catheters. The objective of this work is to present a simple analytical approach to address this concern and to demonstrate the agreement with experimental results. The first hypothesis is that a long conductive structure couples with the electric field of the radio frequency (RF) transmit coil. The second hypothesis is that this coupling induces high voltages near the wire ends. These voltages can cause tissue heating due to induced currents. The experimental results show an increase in coupling when moving a guide wire toward the wall of an RF transmit coil, documented with a temperature increase of a saline solution in close proximity to the tip of the guide wire. The coupling of the wire not only presents a potential hazard to the patient, but also interferes with the visualization of the wire. A safe alternative would be the use of nonconducting guide wires. J. Magn. Reson. Imaging 2001;13:105-114.

Interventional MRI-guided brain biopsies using inductively coupled surface coils

The technical realization of inductively coupled surface coils for interventional MR-guided procedures, and the application to brain biopsies in a 0.2 T magnet is described. The advantages compared to standard coils are discussed, and the results of 26 biopsies on eight different neuropathologic diagnoses from varying locations within the brain are presented. Initial experience shows that inductively coupled coils can offer an increased number of indications for interventional procedures in the brain, easier handling of sterility, and often a better access for the surgeon, compared to the use of standard MR head coils.

Hardware considerations for MR imaging physics

Since its commercial introduction as a diagnostic tool in 1984, MR imaging has undergone dramatic improvements in all the features that define image quality. This article discusses what a modern MR imaging scanner should look like and how the components of an MR system, especially the magnet, gradient, and RF components must be matched with one another to ensure optimal performance.

[Physical parameters in the use of MRI tomography. Limitation due to physiologic reactions and guidelines. Radiation Protection Commission]

PURPOSE

The standards and regulations concerning the protection of patients and operator staff within the context of MRI are compiled. Resulting consequences regarding physical parameters are evaluated.

MATERIAL AND METHODS

The static magnetic field, heating effects caused by RF-fields and acoustical noise are outlined. The actual boundaries of these parameters are compared against the relevant published standards. Peripheral stimulation limits due to pulsed gradient fields have been determined in a new clinical study.

RESULTS

Many parameters recommended for the normal operating mode are already exceeded during routine MRI. Referring to our clinical study, we found that limits recommended in the MRI relevant standards are unnecessarily conservative and can actually be doubled.

CONCLUSIONS

The applicable national and international standards and regulations show (at least partly) that serious differences in the definition of terms and values exist. The application of these standards would be much easier if they were made uniform. The values defined in the MR-specific standards should be adapted to actual knowledge concerning patients' safety.

Comparative efficacy of azelastine nasal spray and terfenadine in seasonal and perennial rhinitis

The efficacy and tolerability of intranasal azelastine (0.14 mg/nostril twice daily) and oral terfenadine (60 mg twice daily) were compared under double-blind conditions in two 6-week, multicenter, parallel-group studies, including 167 patients suffering from seasonal and 52 patients suffering from perennial allergic rhinitis. In both studies, patients were symptomatic on entry and showed significant improvement on both treatments within the first 8 d of therapy, showing little further improvement with continued treatment. Symptoms most pronounced on entry--nasal itching, rhinorrhea, sneezing, and nasal obstruction--responded best to treatment (response rates 80-90%). Objective signs such as mucosal swelling and conjunctivitis improved in a manner parallel to symptoms. In perennial rhinitis, azelastine showed a trend to a superior relief of rhinorrhea and nasal obstruction, whereas terfenadine showed a trend toward better control of sneezing and nasal itchiness. No clinically relevant or statistically significant differences between treatments could be identified. The incidence of adverse effects of possible causal relationship to therapy was low. The most frequent effects in azelastine-treated patients were related to application site disorders, e.g., nasal irritation. Results indicate that with the dose used azelastine nasal spray is an effective treatment for both seasonal and perennial allergic rhinitis.

Intranasal treatment of perennial allergic rhinitis. Comparison of azelastine nasal spray and budesonide nasal aerosol

The efficacy and tolerability of azelastine (CAS 58581-89-8) nasal spray (0.14 mg/nostril b.i.d.) and budesonide (CAS 51333-22-3) nasal aerosol (0.05 mg/nostril b.i.d.) were compared in a 6-week, multicentre, parallel group study of 193 patients suffering from perennial allergic rhinitis. Total rhinitis symptoms complex (TSC) scores derived from 10 rhinitis symptoms improved during treatment by a mean of 11.4 +/- 6.8 with azelastine and 10.8 +/- 6.4 with budesonide. Response rates, defined as a decrease in TSC of at least 50% at the end of therapy, was 79% with azelastine and 73% with budesonide. There were no significant differences between the treatment groups with respect to either target variable. Objective measurements of nasal flow rate showed a return to normal values during the 6-week therapy. Signs of rhinitis identified by rhinoscopic examination improved in parallel to symptoms. Both medications were well tolerated. The incidence of adverse events of possibly causal relationship to therapy was low. The most frequent event in azelastine treated patients was the experience of an "unpleasant" taste or smell. Occasional epistaxis occurred in both treatment groups but more frequently with budesonide. Results indicate that with the dose used azelastine nasal spray is an effective treatment for perennial allergic rhinitis comparable to that of budesonide nasal aerosol.