Treatment of In-stent Restenosis of the Internal Carotid Artery Using Drug-eluting Balloons

PURPOSE

In-stent restenosis (ISR) following internal carotid artery (ICA) stenting is relatively common with an estimated incidence of 5%. Treatment options include repeat angioplasty with conventional or drug-eluting balloons (DEB), repeat stent angioplasty and surgical intervention. Application of DEB in ISR of the coronary and peripheral arteries is an established method; however, data on DEB treatment of ICA ISR are sparse. In this work, results from a retrospective cohort of 45 patients harboring 46 ICA ISR lesions treated with DEB angioplasty are presented.

METHODS

Clinical, procedural and imaging data from DEB angioplasty treatment of 46 high-grade ICA ISR lesions in 45 patients, performed between 2013 and 2021 were collected. A single type of DEB (Elutax, Aachen Resonance, Aachen, Germany) was used in all procedures. Imaging follow-up was performed by regular Doppler ultrasound (DUS), verified by computed tomography angiography (CTA) in cases suspicious for a recurrent ISR.

RESULTS

Technical success was 100%. Intraprocedural and postprocedural complications were not encountered. Clinical follow-up was obtained in all patients. Recurrent stroke in the affected territory was not encountered. A recurrent ISR following DEB treatment was confirmed by DUS and CTA in 4/46 (8.7%) of the lesions and were retreated with DEB. A third recurrent ISR occurred in a single case (2%) and following a second DEB retreatment there were no signs of a fourth recurrence after 36 months follow-up.

CONCLUSION

The use of DEB angioplasty is a safe and effective treatment of ICA ISR lesions, yielding significantly better results compared to other modalities. Randomized multicenter studies are warranted.

Meta-analysis identifies native priority as a mechanism that supports the restoration of invasion-resistant plant communities

The restoration of invasion-resistant plant communities is an important strategy to combat the negative impacts of alien invasions. Based on a systematic review and meta-analysis of seed-based ecological restoration experiments, here we demonstrate the potential of functional similarity, seeding density and priority effect in increasing invasion resistance. Our results indicate that native priority is the most promising mechanism to control invasion that can reduce the performance of invasive alien species by more than 50%. High-density seeding is effective in controlling invasive species, but threshold seeding rates may exist. Overall seeding functionally similar species do not have a significant effect. Generally, the impacts are more pronounced on perennial and grassy invaders and on the short-term. Our results suggest that biotic resistance can be best enhanced by the early introduction of native plant species during restoration. Seeding of a single species with high functional similarity to invasive alien species is unpromising, and instead, preference should be given to high-density multifunctional seed mixtures, possibly including native species favored by the priority effect. We highlight the need to integrate research across geographical regions, global invasive species and potential resistance mechanisms.

Manifestation of Triploid Heterosis in the Root System after Crossing Diploid and Autotetraploid Energy Willow Plants

Successful use of woody species in reducing climatic and environmental risks of energy shortage and spreading pollution requires deeper understanding of the physiological functions controlling biomass productivity and phytoremediation efficiency. Targets in the breeding of energy willow include the size and the functionality of the root system. For the combination of polyploidy and heterosis, we have generated triploid hybrids (THs) of energy willow by crossing autotetraploid willow plants with leading cultivars (Tordis and Inger). These novel Salix genotypes (TH3/12, TH17/17, TH21/2) have provided a unique experimental material for characterization of Mid-Parent Heterosis (MPH) in various root traits. Using a root phenotyping platform, we detected heterosis (TH3/12: MPH 43.99%; TH21/2: MPH 26.93%) in the size of the root system in soil. Triploid heterosis was also recorded in the fresh root weights, but it was less pronounced (MPH%: 9.63-19.31). In agreement with root growth characteristics in soil, the TH3/12 hybrids showed considerable heterosis (MPH: 70.08%) under in vitro conditions. Confocal microscopy-based imaging and quantitative analysis of root parenchyma cells at the division-elongation transition zone showed increased average cell diameter as a sign of cellular heterosis in plants from TH17/17 and TH21/2 triploid lines. Analysis of the hormonal background revealed that the auxin level was seven times higher than the total cytokinin contents in root tips of parental Tordis plants. In triploid hybrids, the auxin-cytokinin ratios were considerably reduced in TH3/12 and TH17/17 roots. In particular, the contents of cytokinin precursor, such as isopentenyl adenosine monophosphate, were elevated in all three triploid hybrids. Heterosis was also recorded in the amounts of active gibberellin precursor, GA19, in roots of TH3/12 plants. The presented experimental findings highlight the physiological basics of triploid heterosis in energy willow roots.

Highly specific and non-invasive imaging of Piezo1-dependent activity across scales using GenEPi

Mechanosensing is a ubiquitous process to translate external mechanical stimuli into biological responses. Piezo1 ion channels are directly gated by mechanical forces and play an essential role in cellular mechanotransduction. However, readouts of Piezo1 activity are mainly examined by invasive or indirect techniques, such as electrophysiological analyses and cytosolic calcium imaging. Here, we introduce GenEPi, a genetically-encoded fluorescent reporter for non-invasive optical monitoring of Piezo1-dependent activity. We demonstrate that GenEPi has high spatiotemporal resolution for Piezo1-dependent stimuli from the single-cell level to that of the entire organism. GenEPi reveals transient, local mechanical stimuli in the plasma membrane of single cells, resolves repetitive contraction-triggered stimulation of beating cardiomyocytes within microtissues, and allows for robust and reliable monitoring of Piezo1-dependent activity in vivo. GenEPi will enable non-invasive optical monitoring of Piezo1 activity in mechanochemical feedback loops during development, homeostatic regulation, and disease.

Development and characterization of novel jGCaMP8f calcium sensor variants with improved kinetics and fluorescence response range

Introduction

Genetically encoded biosensors for monitoring intracellular calcium changes have advanced our understanding of cell signaling and neuronal activity patterns in health and disease. Successful application of GCaMP biosensors to a wide range of biological questions requires that sensor properties such as brightness and dynamic range, ligand affinity and response kinetics be tuned to the specific conditions or phenomena to be investigated. Random as well as rational targeted mutations of such sensor molecules have led to a number of important breakthroughs in this field, including the calcium sensors GCaMP6f and GCaMP6f_u. jGCaMP8f of the most recently developed generation is promising a step-change in in vivo imaging with further increased fluorescence dynamic range. Here, we critically examine the biophysical properties of jGCaMP8f and report development by rational design of two novel variants of jGCaMP8f.

Methods

We determined the in vitro biophysical properties of jGCaMP8f and selected variants by fluorescence spectroscopies and compared their performance monitoring intracellular Ca²⁺ transients with previously developed fast and bright GCaMP sensors by live cell imaging.

Results

We demonstrate that the physiologically highly relevant Mg²⁺ not only majorly affects the kinetic responses of GCaMPs but also their brightness and fluorescence dynamic range. We developed novel variants jGCaMP8f L27A which has threefold faster off-kinetics and jGCaMP8f F366H which shows a ∼3-fold greater dynamic range than jGCaMP8f, in vitro as well as in HEK293T cells and endothelial cell line HUVEC in response to ATP stimulation.

Discussion

We discuss the importance of optimization of biosensors for studying neurobiology in the context of the novel variants of jGCaMP8f. The jGCaMP8f F366H variant with a large dynamic range has the potential to improve in vivo imaging outcomes with increased signal-to-noise ratio. The L27A variant with faster kinetics than jGCaMP8f has larger cellular responses than previous fast GCaMP variants. The jGCaMP8f generation and novel improved variants presented here will further increase the application potential of GECIs in health and disease.

The long-term effect of initial restoration intervention, landscape composition, and time on the progress of Pannonic sand grassland restoration

To help upscale ecological restoration of degraded lands, landscape factors and longer time scales should be considered when assessing restoration efforts. We evaluated the impact of initial restoration intervention, landscape composition, and elapsed time since the restoration began on the long-term progress of Pannonic sand grassland restoration. Treatments (seeding, mowing, and carbon amendment) were implemented for 6–7 years and monitoring lasted up to 23 years after the first treatment applications in eight experimental blocks belonging to three field experiments. The abundance of target/neophyte species, and distance from primary grasslands and plantations (as major source of target/neophyte species) were estimated in 500 m landscape buffers around each block to characterize landscape composition. Restoration progress was calculated as the difference between the relative cover of target/neophyte species in treatment and control plots. Restoration intervention and neophyte abundance in the landscape had a significant effect on the restoration progress, but time did not. Seeding had the highest positive effect on target species and also prevented invasion by neophyte species. Higher abundance of neophytes in the landscape and the proximity to plantations increased the cover of neophytes in treatment plots. We conclude that restoration interventions may have a greater impact on restoration progress in the longer term than landscape factors or elapsed time. Seeding proved to be the best method in restoring sand grasslands by both favoring target species and controlling invasion. From the landscape factors, the abundance of neophyte species and distance to plantations should be considered when prioritizing areas and efforts for restoration.

P-selectin mobility undergoes a sol-gel transition as it diffuses from exocytosis sites into the cell membrane

In response to vascular damage, P-selectin molecules are secreted onto the surface of cells that line our blood vessels. They then serve as mechanical anchors to capture leucocytes from the blood stream. Here, we track individual P-selectin molecules released at the surface of live endothelial cells following stimulated secretion. We find P-selectin initially shows fast, unrestricted diffusion but within a few minutes, movement becomes increasingly restricted and ~50% of the molecules become completely immobile; a process similar to a sol-gel transition. We find removal of the extracellular C-type lectin domain (ΔCTLD) and/or intracellular cytoplasmic tail domain (ΔCT) has additive effects on diffusive motion while disruption of the adapter complex, AP2, or removal of cell-surface heparan sulphate restores mobility of full-length P-selectin close to that of ΔCT and ΔCTLD respectively. We have found P-selectin spreads rapidly from sites of exocytosis and evenly decorates the cell surface, but then becomes less mobile and better-suited to its mechanical anchoring function.

P-selectin recruits leucocytes to regions of blood vessel damage. Using single molecule imaging, we find newly secreted P-selectin spreads rapidly across the plasma membrane and then becomes immobilized and better-suited to leucocyte capture.

Early Return to Play After Anterior Cruciate Ligament Reconstruction: Is It Worth the Risk?

Objective

To compare the outcomes of a 6-month-long accelerated rehabilitation with a 12-month-long rehabilitation. There is no consensus on the optimal duration of rehabilitation after anterior cruciate ligament reconstruction (ACLR). Trends in the past decades have shifted towards accelerated programs, often resulting in a return to play (RTP) at 4–6 months, postoperatively. However, longer rehabilitation cycles have recently experienced renaissance due to a greater understanding of graft remodeling.

Methods

Adult athletes who underwent ACLR between 2015 and 2018 by the same surgeon were included and followed-up prospectively for 24 months. Participants were allocated into two groups based on their RTP (6 months vs. 12 months) and compared with graft elongation, reoperation rate, and sports career (quit or continue) outcomes.

Results

Fifty-four patients underwent accelerated rehabilitation and 92 completed conventional rehabilitation. The accelerated rehabilitation was significantly associated with graft elongation—the accelerated rehabilitation group (n=9) and the conventional rehabilitation group (n=0), p<0.001—and need for reoperation—the accelerated rehabilitation group (n=5) and the conventional rehabilitation group (n=1), p=0.026. Although the relationship between rehabilitation time and quitting competitive sports did not reach significance at 0.05 level (p=0.063), it was significant when p<0.1, thereby showing a clear trend.

Conclusion

Accelerated rehabilitation increased graft elongation risk. Knee laxity ≥3 mm measured at 6 months after ACLR should be accompanied by RTP time frame re-evaluation. Arthrometry checkups or routine magnetic resonance imaging shortly after RTP may be considered in cases of accelerated rehabilitation.

Triploid Hybrid Vigor in Above-Ground Growth and Methane Fermentation Efficiency of Energy Willow

Hybrid vigor and polyploidy are genetic events widely utilized to increase the productivity of crops. Given that bioenergy usage needs to be expanded, we investigated triploid hybrid vigor in terms of the biology of biomass-related willow traits and their relevance to the control of biomethane production. To produce triploid hybrid genotypes, we crossed two female diploid Swedish cultivars (Inger, Tordis) with two male autotetraploid willow (Salix viminalis) variants (PP-E7, PP-E15). Field studies at two locations and in two successive years recorded considerable midparent heterosis (MPH%) in early shoot length that ranged between 11.14 and 68.85% and in the growth rate between 34.12 and 97.18%. The three triploid hybrids (THs) developed larger leaves than their parental cultivars, and the MPH% for their CO2 assimilation rate varied between 0.84 and 25.30%. The impact of hybrid vigor on the concentrations of plant hormones in these TH genotypes reflected essentially different hormonal statuses that depended preferentially on maternal parents. Hybrid vigor was evinced by an elevated concentration of jasmonic acid in shoot meristems of all the three THs (MPH:29.73; 67.08; 91.91%). Heterosis in auxin-type hormones, such as indole-3-acetic acid (MPH:207.49%), phenylacetic acid (MPH:223.51%), and salicylic acid (MPH:27.72%) and benzoic acid (MPH:85.75%), was detectable in the shoots of TH21/2 plants. These hormones also accumulated in their maternal Inger plants. Heterosis in cytokinin-type hormones characterized the shoots of TH3/12 and TH17/17 genotypes having Tordis as their maternal parent. Unexpectedly, we detected abscisic acid as a positive factor in the growth of TH17/17 plants with negative MPH percentages in stomatal conductance and a lower CO2 assimilation rate. During anaerobic digestion, wood raw materials from the triploid willow hybrids that provided positive MPH% in biomethane yield (6.38 and 27.87%) showed negative MPH in their acid detergent lignin contents (from -8.01 to -14.36%). Altogether, these insights into controlling factors of above-ground growth parameters of willow genotypes support the utilization of triploid hybrid vigor in willow breeding to expand the cultivation of short rotation energy trees for renewable energy production.

Effects of Exercise Dose and Detraining Duration on Mobility at Late Midlife: A Randomized Clinical Trial

BACKGROUND

Office workers near retirement tend to be sedentary and can be prone to mobility limitations and diseases. We examined the dose effects of exergaming volume and duration of detraining on motor and cognitive function in office workers at late midlife to reduce sedentariness and mobility limitations.

METHODS

In an assessor-blinded randomized trial, 160 workers aged 55-65 years performed physically active video games in a nonimmersive form of virtual reality (exergaming) in small, supervised groups for 1 h, 1×, 2×, or 3×/week for 8 weeks followed by detraining for 8 and 16 weeks. Exergaming comprises high-intensity, full-body sensorimotor coordination, balance, endurance, and strengthening exercises. The primary outcome was the 6-minute walk test (6MWT), and secondary outcomes were body mass, self-reported physical activity, sleep quality, Berg Balance Scale, Short Physical Performance Battery, fast gait speed, dynamic balance, heart rate recovery after step test, and 6 cognitive tests.

RESULTS

The 3 groups were not different in any of the outcomes at baseline (all p > 0.05). The outcomes were stable and had acceptable reliability (intraclass correlation coefficients ≥0.334) over an 8-week control period. Training produced an inverted U-shaped dose response of no (1×), most (2×), and medium (3×/week) effects of exergaming volume in most motor and selected cognitive outcomes. The distance walked in the 6MWT (primary outcome) increased most (94 m, 19%, p < 0.05), medium (57 m, 12%, p < 0.05), and least (4 m, 1%) after exergaming 2×, 3×, or 0× (control) (all different p < 0.05). The highest responders tended to retain the exercise effects over 8 weeks of detraining, independent of training volume. This maintenance effect was less consistent after 16 weeks of detraining.

CONCLUSION

Less was more during training and lasted longer after detraining. A medium dose volume of exergaming produced the largest clinically meaningful improvements in mobility and selected cognitive tests in 60-year-old office workers with mild mobility limitations and intact cognition.

Jobb oldali videoasszisztált thoracoscopos thymectomia a thymoma nélküli, felnőttkori myasthenia gravis sebészi kezelésében

Összefoglaló. Bevezetés: A myasthenia gravis javallatával végzett csecsemőmirigy-eltávolítás sebésztechnikai szempontból lényegesen megváltozott az elmúlt közel 30 évben. A standard műtétnek számító transsternalis és transcervicalis thymectomia mellett elterjedt a videoasszisztált thoracoscopos sebészeti (VATS), később pedig a robot sebészeti megoldás is. Két intézetünkben 2011-2012-ben vezettük be a VATS thymectomiát. Módszer: A többféle technikai megoldás közül a mediastinumot a jobb mellüreg felől megközelítő utat választottuk. Eleinte 3, később 2 pontos perimammaris portot készítettünk a thymus elérésére a beteg háton fekvő helyzetében. Minden esetben ultrahangos vágóeszközt alkalmaztunk. Kiterjesztett thymectomiára törekedve a perithymikus zsírszövetet is eltávolítottuk, szélesen megnyitva a bal oldali mellüreget is. A betegek kiválasztásában az átlagos testsúlyú vagy soványabb betegeket részesítettük előnyben. Eredmények: 8 év és 4 hónap alatt 92 beteget műtöttünk a fenti módszerrel thymoma nélküli myasthenia gravis alapbetegséggel. 20 férfi és 72 nő. Átlagéletkor 33,1 év (19-75 év). A műtéti idő 35-160 percig terjedt, átlagosan 82,3 perc volt. A tömegesebb mediastinalis zsírszövet néhány betegnél nehezítette a tájékozódást és a maradéktalan eltávolítást. Műtét alatt 4 esetben érsérülés és 3 ellenoldali tüdősérülés következett be. Két konverziót végeztünk (1-1 sternotomia és thoracotomia). Idegsérülés nem történt. Tíz beteg igényelt néhány órás művi lélegeztetést a műtét után, a többi beteget a műtőasztalon extubáltuk. Reintubáció, tracheostomia, légzési elégtelenség, műtéti halálozás nem volt. Az intenzív ápolási idő átlaga: 1,1 (0-11) nap. A teljes kórházi ápolási idő átlaga: 4,8 (3-15) nap. A drenázsidő 1-4 nap, átlagosan 1,16 nap. Két beteg (2,41%) halt meg a műtétet követően 1 és 5 éven belül. További 81 beteg 12-108 (átlag: 48) hónapos követése során a myastheniás állapotban 21 (25,3%) betegnél komplett, 4 (4,82%) betegnél gyógyszeres remisszió, 20 (24,1%) betegnél minimális manifesztáció, 28 (33,73%) betegnél egyéb javulás volt megállapítható. 4 (4,82%) beteg állapota változatlan maradt, 4 (4,82%) betegé pedig romlott. Következtetés: A VATS thymectomia teljesen új utat jelent a transsternalis módszerben járatos sebészek számára. A tömegesebb mediastinalis zsírszövet nagyon megnehezíti a műtétet. A perioperatív szak nagyon kedvező a betegek számára, és a késői eredmények is elfogadhatóak. Kérdéses, hogy a thymus minden esetben maradéktalanul eltávolítható-e ezzel a módszerrel.

SUMMARY

INTRODUCTION

Surgical technique of thymectomy performed for treatment of myasthenia gravis has considerably changed in the last almost 30 years. In addition to standard interventions - transsternal and transcervical thymectomy -, video-assisted thoracoscopic interventions (VATS), later on robotic surgery came into general use. In our two institutions, we apply VATS thymectomy since 2011.

METHODS

There are several different surgical techniques for this purpose; we approached the mediastinum through the right thoracic cavity. We prepared initially 3, later on 2 perimammal ports for the access of the thymus; the patients were in supine position during surgery. We used an ultrasonic cutting device in all cases. In order to perform extended thymectomy, we removed the fatty tissue around the thymus and opened widely the left thoracic cavity, too. During patient enrollment, we preferred patients with normal or lower body weight.

RESULTS

During 8 years and 4 months, we operated on 92 patients using this method for myasthenia gravis without thymoma; there were 20 male and 72 female patients at the age of 33 years on average (19-75 years). Duration of surgery was 35-160 minutes, 82.3 minutes on average. The bulky fatty tissue around the thymus made the orientation and the complete removal more difficult in a few patients. We experienced vascular injury in 4 cases and injury of the contralateral lung in 3 cases. Conversion was necessary in 2 cases (1 sternotomy and 1 thoracotomy), there were no nerve injuries. Assisted ventilation was necessary in case of ten patients in the postoperative period for a few hours; all other patients were extubated on the operating table. There was no need for repeated intubation and tracheostomy; there was no respiratory insufficiency and perioperative mortality. Duration of ICU care was 1.1 days on the average (0-11 days), that of the total hospital care 4.8 days on average (3-15 days). Duration of thoracic drainage was 1.16 days on average (1-4 days). Two patients (2.41%) died within one and five years after surgery. During 12-108 months (48 months on average) follow-up of 81 patients, 21 patients (25.3%) suffering from myasthenia total recovery was observed, pharmacologic remission was achieved in 4 patients (5.3%), minimal manifestation remained in 23 patients (24.1%), while in 28 patients (33.73%) other improvement was observed. The status of 4 patients (4.82%) remained unchanged and that of 4 patients (5.3%) worsened.

CONCLUSION

VATS thymectomy represents a completely new surgical method for surgeons having experience in transsternal surgical technique. Bulky mediastinal fatty tissue makes surgery very difficult. The perioperative period is advantageous for the patients and also the long term follow-up results are acceptable. It is questionable that the thymus can be completely removed with this method in all cases.

High Frequency and Intensity Rehabilitation in 641 Subacute Ischemic Stroke Patients

OBJECTIVES

To determine the effects of exergaming on quality of life (QoL), motor, and clinical symptoms in subacute stroke patients.

DESIGN

A pseudorandomized controlled trial, using a before-after test design.

SETTING

University hospital.

PARTICIPANTS

Subacute, ischemic stroke outpatients (N=3857), 680 of whom were randomized and 641 completed the study.

INTERVENTIONS

We determined the effects of 5 times a week twice daily (EX2; 50 sessions; n=286) and once daily (EX1; 25 sessions; n=272) exergaming and low-intensity standard care (control [CON]; 25 sessions; n=83) on clinical, mobility, blood pressure (BP), and QoL outcomes.

MAIN OUTCOME MEASURES

The primary outcome was Modified Rankin Scale. Secondary outcomes were activities of daily living, 5 aspects of health-related QoL, Beck Depression Inventory, 6-minute walk test (6MWT), Berg Balance Scale (BBS), and static balance (center of pressure).

RESULTS

During exercise, the peak heart rate was 134, 134, and 126 beats per minute in the EX2, EX1, and CON groups, respectively. mRS improved similarly in the EX2 (-1.8; effect size, d=-4.0) and EX1 (-1.4; d=-2.6) groups, but more than in the CON group (-0.7; d=-0.6). QoL, Barthel Index, BBS, 6MWT, and standing posturography improved more in the EX2 group and the same in the EX1 and CON groups. Systolic and diastolic resting BP decreased more in the EX2 and EX1 groups than in the CON group. The intervention effects did not differ between men (n=349) and women (n=292).

CONCLUSIONS

Twice daily compared with once daily high-intensity exergaming or once daily lower intensity standard care produced superior effects on clinical and motor symptoms, BP, and QoL in male and female subacute ischemic stroke participants.

Kinetic Mechanisms of Fast Glutamate Sensing by Fluorescent Protein Probes

We have developed probes based on the bacterial periplasmic glutamate/aspartate binding protein with either an endogenously fluorescent protein or a synthetic fluorophore as the indicator of glutamate binding for studying the kinetic mechanism of glutamate binding. iGluSnFR variants termed iGlu_h, iGlu_m, and iGlu_l cover a broad range of K_d-s (5.8 μM and 2.1 and 50 mM, respectively), and a novel fluorescently labeled indicator, Fl-GluBP, has a K_d of 9.7 μM. The fluorescence response kinetics of all the probes are consistent with a two-step mechanism involving ligand binding and isomerization either of the apo or the ligand-bound binding protein. Although the previously characterized ultrafast indicators iGlu_u and iGlu_f had monophasic fluorescence enhancement that occurred in the rate limiting isomerization step, the sensors described here all have biphasic binding kinetics with fluorescence increases occurring both in the glutamate binding and the isomerization steps. For iGlu_m and iGlu_l, the data indicate prebinding conformational change followed by ligand binding. In contrast, for iGlu_h and Fl-GluBP, glutamate binding is followed by isomerization. Thus, the effects of structural heterogeneity introduced by single amino acid changes around the binding site on the kinetic path of interactions with glutamate are revealed. Remarkably, glutamate binding with a diffusion-limited rate constant to iGlu_h and Fl-GluBP is detected for the first time, hinting at the underlying mechanism of the supremely rapid activation of the highly homologous α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor by glutamate binding.

Antibody-Mediated Rejection in a Multiple Lung Transplant Patient: A Case Report

Lung transplant is an effective way to treat many end-stage lung diseases. However, one of the main barriers of allograft organ transplant is still the immunologic rejection of transplanted tissue, which is a response of the HLA molecules. Rejection is a complex process involving both T-cell-mediated delayed-type hypersensitivity reactions and antibody-mediated hypersensitivity reactions to histocompatibility molecules on foreign grafts. We report the case of a 25-year-old female patient with cystic fibrosis who underwent 2 lung transplants because of her initial diagnosis and appearance of bronchiolitis obliterans syndrome after the first transplant. Only 13 months after the second transplant, despite the therapies applied, a new rejection occurred associated with high mean fluorescent intensity donor-specific antibody levels, which resulted later in the death of the patient. The present case draws attention to the importance of matching HLA molecules between donor and recipient in addition to immunosuppressive therapy.

The kinetic mechanisms of fast-decay red-fluorescent genetically encoded calcium indicators

Genetically encoded calcium indicators (GECIs) are useful reporters of cell-signaling, neuronal, and network activities. We have generated novel fast variants and investigated the kinetic mechanisms of two recently developed red-fluorescent GECIs (RGECIs), mApple-based jRGECO1a and mRuby-based jRCaMP1a. In the formation of fluorescent jRGECO1a and jRCaMP1a complexes, calcium binding is followed by rate-limiting isomerization. However, fluorescence decay of calcium-bound jRGECO1a follows a different pathway from its formation: dissociation of calcium occurs first, followed by the peptide, similarly to GCaMP-s. In contrast, fluorescence decay of calcium-bound jRCaMP1a occurs by the reversal of the on-pathway: peptide dissociation is followed by calcium. The mechanistic differences explain the generally slower off-kinetics of jRCaMP1a-type indicators compared with GCaMP-s and jRGECO1a-type GECI: the fluorescence decay rate of f-RCaMP1 was 21 s-1, compared with 109 s-1 for f-RGECO1 and f-RGECO2 (37 °C). Thus, the CaM-peptide interface is an important determinant of the kinetic responses of GECIs; however, the topology of the structural link to the fluorescent protein demonstrably affects the internal dynamics of the CaM-peptide complex. In the dendrites of hippocampal CA3 neurons, f-RGECO1 indicates calcium elevation in response to a 100 action potential train in a linear fashion, making the probe particularly useful for monitoring large-amplitude, fast signals, e.g. those in dendrites, muscle cells, and immune cells.

Az út Jessica Jonesig Feminista potenciál és megvalósulás a szuperhőssorozatokban

A dolgozat a szuperhős-tematikájú televíziós és websorozatokat vizsgálja, elsősorban azok női karaktereinek ábrázolását és a család szerepét a történeteken belül. Bár a szuperhősök megjelenése a populáris kultúrában évről évre látványosan növekszik, a női hősökkel foglalkozó alkotások viszonylag sokáig várattak magukra, főként, ha olyan darabot keresünk, amely a bevétel tekintetében is sikeres volt. A filmvásznon erre egészen Csodanő legújabb reinkarnációjáig kellett várnunk, a Gal Gadot főszereplésével készült és egy női rendező kezei közül kikerült Wonder Womanre (Patty Jenkins, 2017). A sorozatok tekintetében pedig az Alias Investigations nyomozónőjének története, a Jessica Jones (Melissa Rosenberg, 2015-2019) tekinthető igazi vízválasztónak. A sorozatokban megjelenő különböző természetfeletti vagy szupererővel rendelkező női karakterek vizsgálata során a nőiség fogalmak és feminizmusok változása a zsáner alakulását szemlélteti, amit az is meghatároz a 2010-es évektől kezdődően, hogy a szériák televíziós csatornák vagy streamingszolgáltatók számára készülnek-e.

Ultrafast glutamate sensors resolve high-frequency release at Schaffer collateral synapses

Glutamatergic synapses display a rich repertoire of plasticity mechanisms on many different time scales, involving dynamic changes in the efficacy of transmitter release as well as changes in the number and function of postsynaptic glutamate receptors. The genetically encoded glutamate sensor iGluSnFR enables visualization of glutamate release from presynaptic terminals at frequencies up to ∼10 Hz. However, to resolve glutamate dynamics during high-frequency bursts, faster indicators are required. Here, we report the development of fast (iGlu f ) and ultrafast (iGlu u ) variants with comparable brightness but increased Kd for glutamate (137 μM and 600 μM, respectively). Compared with iGluSnFR, iGlu u has a sixfold faster dissociation rate in vitro and fivefold faster kinetics in synapses. Fitting a three-state model to kinetic data, we identify the large conformational change after glutamate binding as the rate-limiting step. In rat hippocampal slice culture stimulated at 100 Hz, we find that iGlu u is sufficiently fast to resolve individual glutamate release events, revealing that glutamate is rapidly cleared from the synaptic cleft. Depression of iGlu u responses during 100-Hz trains correlates with depression of postsynaptic EPSPs, indicating that depression during high-frequency stimulation is purely presynaptic in origin. At individual boutons, the recovery from depression could be predicted from the amount of glutamate released on the second pulse (paired pulse facilitation/depression), demonstrating differential frequency-dependent filtering of spike trains at Schaffer collateral boutons.

Relaxed chromatin induced by histone deacetylase inhibitors improves the oligonucleotide-directed gene editing in plant cells

Improving efficiency of oligonucleotide-directed mutagenesis (ODM) is a prerequisite for wide application of this gene-editing approach in plant science and breeding. Here we have tested histone deacetylase inhibitor treatments for induction of relaxed chromatin and for increasing the efficiency of ODM in cultured maize cells. For phenotypic assay we produced transgenic maize cell lines expressing the non-functional Green Fluorescent Protein (mGFP) gene carrying a TAG stop codon. These transgenic cells were bombarded with corrective oligonucleotide as editing reagent to recover GFP expression. Repair of green fluorescent protein function was monitored by confocal fluorescence microscopy and flow cytometry was used for quantification of correction events. Sequencing PCR fragments of the GFP gene from corrected cells indicated a nucleotide exchange in the stop codon (TAG) from T to G nucleotide that resulted in the restoration of GFP function. We show that pretreatment of maize cells with sodium butyrate (5-10 mM) and nicotinamide (1-5 mM) as known inhibitors of histone deacetylases can cause elevated chromatin sensitivity to DNase I that was visualized in agarose gels and confirmed by the reduced presence of intact PCR template for the inserted exogenous mGFP gene. Maize cells with more relaxed chromatin could serve as an improved recipient for targeted nucleotide exchange as indicated by an average of 2.67- to 3.62-fold increase in GFP-positive cells. Our results stimulate further studies on the role of the condition of the recipient cells in ODM and testing the application of chromatin modifying agents in other, programmable nuclease-based genome-editing techniques in higher plants.

Design and mechanistic insight into ultrafast calcium indicators for monitoring intracellular calcium dynamics

Calmodulin-based genetically encoded fluorescent calcium indicators (GCaMP-s) are powerful tools of imaging calcium dynamics from cells to freely moving animals. High affinity indicators with slow kinetics however distort the temporal profile of calcium transients. Here we report the development of reduced affinity ultrafast variants of GCaMP6s and GCaMP6f. We hypothesized that GCaMP-s have a common kinetic mechanism with a rate-limiting process in the interaction of the RS20 peptide and calcium-calmodulin. Therefore we targeted specific residues in the binding interface by rational design generating improved indicators with GCaMP6f_u displaying fluorescence rise and decay times (t_1/2) of 1 and 3 ms (37 °C) in vitro, 9 and 22-fold faster than GCaMP6f respectively. In HEK293T cells, GCaMP6f_u revealed a 4-fold faster decay of ATP-evoked intracellular calcium transients than GCaMP6f. Stimulation of hippocampal CA1 pyramidal neurons with five action potentials fired at 100 Hz resulted in a single dendritic calcium transient with a 2-fold faster rise and 7-fold faster decay time (t_1/2 of 40 ms) than GCaMP6f, indicating that tracking high frequency action potentials may be limited by calcium dynamics. We propose that the design strategy used for generating GCaMP6f_u is applicable for the acceleration of the response kinetics of GCaMP-type calcium indicators.

Response of Organ Structure and Physiology to Autotetraploidization in Early Development of Energy Willow Salix viminalis

The biomass productivity of the energy willow Salix viminalis as a short-rotation woody crop depends on organ structure and functions that are under the control of genome size. Colchicine treatment of axillary buds resulted in a set of autotetraploid S. viminalis var. Energo genotypes (polyploid Energo [PP-E]; 2n = 4x = 76) with variation in the green pixel-based shoot surface area. In cases where increased shoot biomass was observed, it was primarily derived from larger leaf size and wider stem diameter. Autotetraploidy slowed primary growth and increased shoot diameter (a parameter of secondary growth). The duplicated genome size enlarged bark and wood layers in twigs sampled in the field. The PP-E plants developed wider leaves with thicker midrib and enlarged palisade parenchyma cells. Autotetraploid leaves contained significantly increased amounts of active gibberellins, cytokinins, salicylic acid, and jasmonate compared with diploid individuals. Greater net photosynthetic CO2 uptake was detected in leaves of PP-E plants with increased chlorophyll and carotenoid contents. Improved photosynthetic functions in tetraploids were also shown by more efficient electron transport rates of photosystems I and II. Autotetraploidization increased the biomass of the root system of PP-E plants relative to diploids. Sections of tetraploid roots showed thickening with enlarged cortex cells. Elevated amounts of indole acetic acid, active cytokinins, active gibberellin, and salicylic acid were detected in the root tips of these plants. The presented variation in traits of tetraploid willow genotypes provides a basis to use autopolyploidization as a chromosome engineering technique to alter the organ development of energy plants in order to improve biomass productivity.

Physical Activity Is Associated with Attention Capacity in Adolescents

OBJECTIVE

To assess the relationships among physical activity, measured objectively, and attention capacity in European adolescents.

STUDY DESIGN

The study included 273 adolescents, aged 12.5-17.5 years, who participated in the Healthy Lifestyle in Europe by Nutrition in Adolescence Study. Participants wore a uniaxial accelerometer for 7 days to measure physical activity. The d2 Test of Attention was administered to assess attention capacity. Multivariate analyses were used to study the association of attention capacity with each measure of physical activity. Receiver operating characteristic analysis was performed to determine thresholds that best discriminate between low and good attention capacity.

RESULTS

After controlling for potential confounding variables (age, sex, body mass index, parental educational level, fat mass, aerobic fitness, and center), adolescents' attention capacity test performances were significantly and positively associated with longer time spent in moderate or moderate-to-vigorous physical activity (MVPA) in free-living conditions (P < .05). Receiver operating characteristic curve analyses revealed that the physical activity thresholds that best discriminated between low/good attention capacities were ≥41 min·day(-1) for moderate, ≥12 min·day(-1) for vigorous, and ≥58 min·day(-1) for MVPA.

CONCLUSION

These findings suggest that promoting MVPA may be have a beneficial effect on attention capacity, an important component of cognition, in adolescents.

Complement receptor type 1 (CR1/CD35) expressed on activated human CD4+ T cells contributes to generation of regulatory T cells

The role of complement in the regulation of T cell immunity has been highlighted recently by several groups. We were prompted to reinvestigate the role of complement receptor type 1 (CR1, CD35) [corrected] in human T cells based on our earlier data showing that activated human T cells produce C3 (Torok et al. (2012) [48]) and also by results demonstrating that engagement of Membrane Cofactor Protein (MCP, CD46) induces a switch of anti-CD35-activated [corrected] helper T cells into regulatory T cells (Kemper et al. (2003) [17]). We demonstrate here that co-ligation of CD46 and CD35, [corrected] the two C3b-binding structures present on activated CD4+ human T cells significantly enhances CD25 expression, elevates granzyme B production and synergistically augments cell proliferation. The role of CR1 in the development of the Treg phenotype was further confirmed by demonstrating that its engagement enhances IL-10 production and reduces IFNγ release by the activated CD4+ T cells in the presence of excess IL-2. The functional in vivo relevance of our findings was highlighted by the immunohistochemical staining of tonsils, revealing the presence of CD4/CD35 [corrected] double positive lymphocytes mainly in the inter-follicular regions where direct contact between CD4+ T cells and B lymphocytes occurs. Regarding the in vivo relevance of the complement-dependent generation of regulatory T cells in secondary lymphoid organs we propose a scenario shown in the figure. The depicted process involves the sequential binding of locally produced C3 fragments to CD46 and CD35 [corrected] expressed on activated T cells, which - in the presence of excess IL-2 - leads to the development of Treg cells.

Dispersal pathways and genetic differentiation among worldwide populations of the invasive weed Centaurea solstitialis L. (Asteraceae)

The natural history of introduced species is often unclear due to a lack of historical records. Even when historical information is readily available, important factors of the invasions such as genetic bottlenecks, hybridization, historical relationships among populations and adaptive changes are left unknown. In this study, we developed a set of nuclear, simple sequence repeat markers and used these to characterize the genetic diversity and population structure among native (Eurasian) and non-native (North and South American) populations of Centaurea solstitialis L., (yellow starthistle). We used these data to test hypotheses about the invasion pathways of the species that were based on historical and geographical records, and we make inferences about historical relationships among populations and demographic processes following invasion. We confirm that the center of diversity and the native range of the species is likely the eastern Mediterranean region in the vicinity of Turkey. From this region, the species likely proceeded to colonize other parts of Europe and Asia via a slow, stepwise range expansion. Spanish populations were the primary source of seed to invade South America via human-mediated events, as was evident from historical records, but populations from the eastern Mediterranean region were also important. North American populations were largely derived from South America, but had secondary contributors. We suggest that the introduction history of non-native populations from disparate parts of the native range have allowed not just one, but multiple opportunities first in South America then again in North America for the creation of novel genotypes via intraspecific hybridization. We propose that multiple intraspecific hybridization events may have created especially potent conditions for the selection of a noxious invader, and may explain differences in genetic patterns among North and South America populations, inferred differences in demographic processes, as well as morphological differences previously reported from common garden experiments.

Human T cell derived, cell-bound complement iC3b is integrally involved in T cell activation

Although the complement system is thought to be mainly involved in innate immunity and in the humoral arm of adaptive responses, evidence implicating that complement impacts T cell responses are accumulating recently. The role of the various activation products of the major complement component C3 were mainly studied so far in animal systems, and investigations regarding the effect of different C3-fragments on human T cells are sparse. Here we show that anti-CD3 activated human T lymphocytes derived from the blood and tonsil of healthy individuals produce C3, and the major cleavage fragment that appears on the T cell surface is iC3b. Based on studies carried out in allogenic system we demonstrate that the T cell membrane bound iC3b binds to the CR3 and probably to CR4 receptors expressed on monocyte-derived dendritic cells, and this interaction leads to significantly enhanced T-cell proliferation. Since neither C3aR and nor C3a binding could be detected on the membrane of anti-CD3 activated T cells, our findings indicate that in humans – in contrast to mice – the C3a peptide is most probably not involved directly in the T cell activation process.

Overproduction of a rice aldo-keto reductase increases oxidative and heat stress tolerance by malondialdehyde and methylglyoxal detoxification

The accumulation of toxic compounds generated by the interaction between reactive oxygen species and polyunsaturated fatty acids of membrane lipids can significantly damage plant cells. A plethora of enzymes act on these reactive carbonyls, reducing their toxicity. Based on the chromosomal localization and on their homology with other stress-induced aldo-keto reductases (AKRs) we have selected three rice AKR genes. The transcription level of OsAKR1 was greatly induced by abscisic acid and various stress treatments; the other two AKR genes tested were moderately stress-inducible. The OsAKR1 recombinant protein exhibited a high nicotinamide adenine dinucleotide phosphate-dependent catalytic activity to reduce toxic aldehydes including glycolysis-derived methylglyoxal (MG) and lipid peroxidation-originated malondialdehyde (MDA). The function of this enzyme in MG detoxification was demonstrated in vivo in E. coli and in transgenic plants overproducing the OsAKR1 protein. Heterologous synthesis of the OsAKR1 enzyme in transgenic tobacco plants resulted in increased tolerance against oxidative stress generated by methylviologen (MV) and improved resistance to high temperature. In these plants lower levels of MDA were detected both following MV and heat treatment due to the activity of the OsAKR1 enzyme. The transgenic tobaccos also exhibited higher AKR activity and accumulated less MG in their leaves than the wild type plants; both in the presence and absence of heat stress. These results support the positive role of OsAKR1 in abiotic stress-related reactive aldehyde detoxification pathways and its use for improvement of stress tolerance in plants.