A numerical simulation of neural fields on curved geometries

Despite the highly convoluted nature of the human brain, neural field models typically treat the cortex as a planar two-dimensional sheet of ne;urons. Here, we present an approach for solving neural field equations on surfaces more akin to the cortical geometries typically obtained from neuroimaging data. Our approach involves solving the integral form of the partial integro-differential equation directly using collocation techniques alongside efficient numerical procedures for determining geodesic distances between neural units. To illustrate our methods, we study localised activity patterns in a two-dimensional neural field equation posed on a periodic square domain, the curved surface of a torus, and the cortical surface of a rat brain, the latter of which is constructed using neuroimaging data. Our results are twofold: Firstly, we find that collocation techniques are able to replicate solutions obtained using more standard Fourier based methods on a flat, periodic domain, independent of the underlying mesh. This result is particularly significant given the highly irregular nature of the type of meshes derived from modern neuroimaging data. And secondly, by deploying efficient numerical schemes to compute geodesics, our approach is not only capable of modelling macroscopic pattern formation on realistic cortical geometries, but can also be extended to include cortical architectures of more physiological relevance. Importantly, such an approach provides a means by which to investigate the influence of cortical geometry upon the nucleation and propagation of spatially localised neural activity and beyond. It thus promises to provide model-based insights into disorders like epilepsy, or spreading depression, as well as healthy cognitive processes like working memory or attention.

A rotary and reciprocating scintillator based fast-ion loss detector for the MAST-U tokamak

The design and unique feature of the first fast-ion loss detector (FILD) for the Mega Amp Spherical Tokamak - Upgrade (MAST-U) is presented here. The MAST-U FILD head is mounted on an axially and angularly actuated mechanism that makes it possible to independently adapt the orientation [0°, 90°] and radial position [1.40 m, 1.60 m] of the FILD head, i.e., its collimator, thus maximizing the detector velocity-space coverage in a broad range of plasma scenarios with different q₉₅. The 3D geometry of the detector has been optimized to detect fast-ion losses from the neutral beam injectors. Orbit simulations are used to calculate the strike map and predict the expected signals. The results show a velocity-space range of [4 cm, 13 cm] in gyroradius and [30°, 85°] in pitch angle, covering the entire neutral beam ion energy range. The optical system will provide direct sight of the scintillator and simultaneous detection with two cameras, giving high spatial and temporal resolution. The MAST-U FILD will shed light on the dominant fast-ion transport mechanisms in one of the world's two largest spherical tokamaks through absolute measurements of fast-ion losses.

Zone-dependent mechanical properties of human articular cartilage obtained by indentation measurements

Emerging 3D printing technology permits innovative approaches to manufacture cartilage scaffolds associated with layer-by-layer mechanical property adaptation. However, information about gradients of mechanical properties in human articular cartilage is limited. In this study, we quantified a zone-dependent change of local elastic modulus of human femoral condyle cartilage by using an instrumented indentation technique. From the cartilage superficial zone towards the calcified layer, a gradient of elastic modulus values between 0.020 ± 0.003 MPa and 6.44 ± 1.02 MPa was measured. To validate the tissue quality, the histological tissue composition was visualized by glycosaminoglycan and collagen staining. This work aims to introduce a new protocol to investigate the zone-dependent mechanical properties of graded structures, such as human articular cartilage. From this knowledge, better cartilage repair strategies could be tailored in the future.

Intrapatient viral diversity and treatment outcome in patients with genotype 3a hepatitis C virus infection on sofosbuvir-containing regimens

Treatment with the direct-acting antiviral agent (DAA) sofosbuvir (SOF), an NS5B inhibitor, and velpatasvir (VEL), an NS5A inhibitor, demonstrates viral cure rates of ≥95% in hepatitis C virus (HCV) genotypes (GT) 1-6. Here, we investigated intrapatient HCV diversity in NS5A and NS5B using Shannon entropy to examine the relationship between viral diversity and treatment outcome. At baseline, HCV diversity was lowest in patients infected with HCV GT3 as compared to the other GTs, and viral diversity was greater in NS5A than NS5B (P < .0001). Treatment outcome with SOF/VEL or the comparator regimen of SOF with ribavirin (RBV) was not correlated with baseline diversity. However, among persons treated with SOF/VEL, a decrease in diversity from baseline was observed at relapse in the majority virologic failures, consistent with a viral bottleneck event at relapse. In contrast, an increase in diversity was observed in 27% of SOF+RBV virologic failures. We investigated whether the increase in diversity was due to an increase in the transition rate, one mode of potential RBV-mediated mutagenesis; however, we found no evidence of this mechanism. Overall, we did not observe that viral diversity at baseline influenced treatment outcome, but the diversity changes observed at relapse can improve our understanding of RBV viral suppression in vivo.

Resistance characterization of ledipasvir and velpatasvir in hepatitis C virus genotype 4

HCV genotype 4 (GT4) has often been overlooked in drug development, even though it infects ~20 million people worldwide. Ledipasvir/sofosbuvir and sofosbuvir/velpatasvir were highly efficacious in GT4 HCV-infected patients from GS-US-337-1119 and GS-US-342-1138. Here, we characterize the resistance profile of ledipasvir (LDV) and velpatasvir (VEL) in patients with GT4 HCV infection. NS5A deep-sequencing was performed for 454 patients infected with HCV GT4 at baseline, including 44 patients enrolled in GS-US-337-1119 and 116 patients enrolled in GS-US-342-1138, and at relapse for patients with virologic failure. LDV and VEL susceptibilities of 56 patient isolates were determined. In GS-US-337-1119, SVR12 rates were 100% for all subtypes except 4b and 4r. Phenotypic assessment of 56 HCV NS5A patient isolates from various GT4 subtypes indicated that LDV had high potency for the common subtypes 4a/d, and subtypes 4c/f/k/l/m/n/o/p/r/t despite the presence of resistance-associated substitutions (RASs). For the rare GT4b, LDV median EC₅₀ was higher, but with a broad range of individual values. Importantly, all GT4b isolates tested had 2-4 NS5A RASs, some including Y93H. Similarly, the 2 GT4r infected patients who had virologic relapse had rare triple RASs. Reversion of these substitutions to the consensus residue significantly increased LDV susceptibility. In GS-US-342-1138, all patients achieved SVR12, regardless of their subtype or presence of RASs. In vitro data confirmed that VEL is potent against all GT4 isolates tested. LDV and VEL are potent antiviral drugs, estimated to be effective against >95% and >99%, respectively, of GT4 HCV isolates.

Auswirkungen der Länge der Trockenstehzeit bei Milchkühen auf Leistung, Gesundheit, Fruchtbarkeit und Kolostrumqualität

In Bezug auf die Milchproduktion ist die Trockenperiode eine unproduktive Zeit. Ferner steigt das Mastitisrisiko, wenn Kühe mit einer Tagesmilchleistung > 12,5 kg trockengestellt werden, was bei Trockenstehzeiten (TZ) von 55–60 Tagen häufig der Fall ist. Hinweise auf positive Auswirkungen einer verkürzten TZ auch auf die Stoffwechselgesundheit zu Beginn der Laktation und das Reproduktionsgeschehen waren der Anlass für diese Übersichtsarbeit. Durch Verzicht auf eine TZ oder deren Verkürzung sinkt die Milchleistung (ML) in der Folgelaktation, besonders ausgeprägt zu Beginn der zweiten Laktation. Es wird angenommen, dass dies unter anderem auf unterschiedlichen Involutions- und Proliferationsprozessen der Milchdrüsen primi- und multiparer Tiere beruht. Die Mehrzahl der Untersuchungsergebnisse spricht dafür, dass eine TZ-Verkürzung die Eutergesundheit nicht negativ, sondern eher positiv beeinflusst. Auch die Kolostrumqualität wird nicht beeinträchtigt. Bei Verzicht auf ein Trockenstellen kommt es lediglich zu einem Verdünnungseffekt. Nach einem Teil der Untersuchungen wird durch Verkürzung der TZ oder einen Verzicht darauf der Energiestoffwechsel zu Beginn der Laktation entlastet. Die eindeutig positiven Auswirkungen zeigten sich jedoch nur für multipare Tiere. Zudem werden die Ergebnisse durch weitere Faktoren (z. B. Melkfrequenz vor und nach dem Kalben) beeinflusst. In verschiedenen Studien wurden positive Auswirkungen einer Verkürzung der TZ auf das Reproduktionsgeschehen nachgewiesen. Die Zeit von der Kalbung bis zur ersten Ovulation wie auch Indikatoren zur Beurteilung des Besamungserfolgs und der Reproduktionsleistung zeigten bei Tieren ohne oder mit verkürzter TZ die besseren Ergebnisse, wobei auch diese vor allem für multipare Kühe zutrafen, während sich für primipare Tiere zum Teil sogar Verschlechterungen ergaben. Insgesamt ist festzustellen, dass sich die Frage nach einer optimalen Länge der TZ nicht allgemeingültig beantworten lässt. Die Festlegung der TZ sollte als betriebsspezifisch und bedarfsorientiert anzuwendendes Managementwerkzeug genutzt werden.

Verlauf einer Herdeninfektion mit BVDV-2

Gegenstand und Ziel: In der Fallstudie werden die klinischen Erkrankungen einer schweren akuten BVDV-2-Infektion mit hohen wirtschaftlichen Verlusten in einer Milchviehherde beschrieben und der Infektionsverlauf labordiagnostisch nachvollzogen. Material und Methoden: In dem Betrieb wurden 25 Kühe plus Nachzucht der Rasse Deutsch Fleckvieh gehalten. Der Betrieb war BHV-1-frei, die durchschnittliche Jahresmilchleistung pro Kuh lag bei 6500 kg. Erkrankungen und Befunde von September 2002 bis April 2003 wurden erfasst und ausgewertet. Der Nachweis von BVDVAntikörpern erfolgte mittels indirektem Antikörper-ELISA. BVDV-Antigene wurden mittels Antigen-ELISA und in der Immunfluoreszenz-Durchflusszytometrie nachgewiesen. Die Zuordnung der isolierten Viren zu BVDV-2 erfolgte mithilfe eines monoklonalen Antikörpers sowie der PCR. Ergebnisse: Sechs Kühe und eine Kalbin erkrankten an hämorrhagischen Enteritiden. Zwei dieser Kühe mussten euthanasiert werden, eine Kuh verendete. Sechs Tiere abortierten oder hatten eine Frühgeburt. Vier Kälber starben und drei lebensschwach geborene oder in den ersten Lebenswochen an profusem Durchfall erkrankte Kälber mussten euthanasiert werden. Zwei Kälber wurden persistent infiziert. Als Ursache der Erkrankungen wurde eine Bestandsinfektion mit BVDV-2 diagnostiziert. Schlussfolgerung und klinische Relevanz: Die Ergebnisse weisen darauf hin, dass die Herde zum Zeitpunkt der Bestandsinfektion BVDV-naiv war. Das Virus muss auch ohne die Anwesenheit eines persistent infizierten Tieres über längere Zeit im Bestand zirkuliert sein.

Stereospecific Nickel-Catalyzed Borylation of Secondary Benzyl Pivalates

A stereoselective nickel-catalyzed direct borylation of enantioenriched secondary benzyl pivalates is described. This methodology is characterized by an intriguing cooperativity of simple nickel and copper salts to promote the targeted C–B bond formation under mild reaction conditions. Unlike classical SN2-type processes, this protocol occurs with a neat retention of configuration, resulting in synthetically versatile benzyl boronic esters with excellent stereochemical fidelity.

The Role of Cutaneous Microbiota Harmony in Maintaining a Functional Skin Barrier

Abstract Not Available

Randomized phase II placebo-controlled study to evaluate the efficacy of topical pure emu oil for joint pain related to adjuvant aromatase inhibitor use in postmenopausal women with early breast cancer: JUST (Joints Under Study)

PURPOSE

Aromatase inhibitors are standard of care in women with hormone receptor-positive early breast cancer. Published evidence demonstrates that adverse effects may have an impact on drug compliance, with arthralgias being one of the most commonly reported adverse effects.

METHODS

Eligible patients were postmenopausal women who had experienced arthralgia following initiation of an aromatase inhibitor. Patients who experienced arthralgias following a minimum of a 3-month treatment on the aromatase inhibitor were randomized to emu oil or placebo oil. The primary endpoint was to assess for a reduction in pain as measured by a visual analogue score after 8 weeks of treatment.

RESULTS

Seventy-three patients comprised the intent-to-treat population, and there was no statistically significant benefit with use of EO. However, there was a statistically significant improvement in pain (visual analogue score was -1.28; p < 0.001) and Brief Pain Inventory severity score -0.88 (p < 0.001), as well as functional interference (Brief Pain Inventory interference -1.10 (p < 0.001) for the entire population following an 8-week administration of EO or placebo oil.

CONCLUSIONS

Arthralgias, as a result of aromatase inhibitor use, may be ameliorated by the use of topical oil massaged onto the joint. Further research into interventions for this common side effect is needed.

Secukinumab and Sustained Improvement in Signs and Symptoms of Patients With Active Ankylosing Spondylitis Through Two Years: Results From a Phase III Study

Objective

Secukinumab improved the signs and symptoms of ankylosing spondylitis (AS) over 52 weeks in the phase III MEASURE 2 study. Here, we report longer‐term (104 weeks) efficacy and safety results.

Methods

Patients with active AS were randomized to subcutaneous secukinumab 150 mg, 75 mg, or placebo at baseline; weeks 1, 2, and 3; and every 4 weeks from week 4. The primary end point was the Assessment of SpondyloArthritis international Society criteria for 20% improvement (ASAS20) response rate at week 16. Other end points included ASAS40, high‐sensitivity C‐reactive protein, ASAS5/6, Bath Ankylosing Spondylitis Disease Activity Index, Short Form 36 health survey physical component summary, ASAS partial remission, EuroQol 5‐domain measure, and Functional Assessment of Chronic Illness Therapy fatigue subscale. End points were assessed through week 104, with multiple imputation for binary variables and a mixed‐effects model repeated measures for continuous variables.

Results

Of 219 randomized patients, 60 of 72 (83.3%) and 57 of 73 (78.1%) patients completed 104 weeks of treatment with secukinumab 150 mg and 75 mg, respectively; ASAS20/ASAS40 response rates at week 104 were 71.5% and 47.5% with both secukinumab doses, respectively. Clinical improvements with secukinumab were sustained through week 104 across all secondary end points. Across the entire treatment period (mean secukinumab exposure 735.6 days), exposure‐adjusted incidence rates for serious infections and infestations, Crohn's disease, malignant or unspecified tumors, and major adverse cardiac events with secukinumab were 1.2, 0.7, 0.5, and 0.7 per 100 patient‐years, respectively. No cases of tuberculosis reactivation, opportunistic infections, or suicidal ideation were reported.

Conclusion

Secukinumab provided sustained improvement through 2 years in the signs and symptoms of AS, with a safety profile consistent with previous reports.