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While expression profile of muscle-specific miRNAs following endurance training is well-characterized, information about exercise-induced changes of metabolism-regulating miRNAs is limited, especially in female and junior athletes. Major aim of this study was to examine a set of miRNAs related to mitochondrial function and metabolism in highly professional junior female athletes. The Hungarian National Junior Triathlon Team (n = 4), completed standardized running and cycling sessions. Expression levels of miR-133a, miR-210, miR-494 and miR-127-3p were determined by RT-qPCR in whole blood and serum samples, withdrawn directly before, and after the exercise, and 24 and 48 h later. The expression of miR-494, miR-127-3p and miR-210 showed strong correlation with each other. In serum, nearly significant increment of miR-127-3p levels was detected, that may be a novel biomarker of exercise adaptation. Its expression was significantly higher than that of miR-210. In whole blood, significantly higher miR-210 than miR-494 and miR-127-3p levels were observed. MiRNA expression profile of the youngest athlete was markedly different compared to others. Our results suggest that miRNAs related to mitochondrial function and metabolism are involved in exercise adaptation. The present study may facilitate further research with larger potential participant pools, contributing to improved prevention and treatment of chronic diseases of civilization., (© 2024. The Author(s).)

Objective: To categorize the temporal progression of subchondral bone alterations induced by compromising meniscus integrity in mouse and rat models of knee osteoarthritis (OA)., Method: Scoping review of investigations reporting subchondral bone changes with appropriate negative controls in the different mouse and rat models of OA induced by compromising meniscus integrity., Results: The available literature provides appropriate temporal detail on subchondral changes in these models, covering the entire spectrum of OA with an emphasis on early and mid-term time points. Microstructural changes of the subarticular spongiosa are comprehensively described; those of the subchondral bone plate are not. In mouse models, global subchondral bone alterations are unidirectional, involving an advancing sclerosis of the trabecular structure over time. In rats, biphasic subchondral bone alterations begin with an osteopenic degeneration and loss of subchondral trabeculae, progressing to a late sclerosis of the entire subchondral bone. Rat models, independently from the applied technique, relatively faithfully mirror the early bone loss detected in larger animals, and the late subchondral bone sclerosis observed in human advanced OA., Conclusion: Mice and rats allow us to study the microstructural consequences of compromising meniscus integrity at high temporal detail. Thickening of the subchondral bone plate, an early loss of thinner subarticular trabecular elements, followed by a subsequent sclerosis of the entire subchondral bone are all important and reliable hallmarks that occur in parallel with the advancing articular cartilage degeneration. Thoughtful decisions on the study design, laterality, selection of controls and volumes of interest are crucial to obtain meaningful data., Competing Interests: Declaration of Competing Interest The authors declare no conflict of interest., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Objective: To investigate whether tibiofemoral alignment influences early knee osteoarthritis (OA). We hypothesized that varus overload exacerbates early degenerative osteochondral changes, and that valgus underload diminishes early OA., Method: Normal, over- and underload were induced by altering alignment via high tibial osteotomy in adult sheep (n = 8 each). Simultaneously, OA was induced by partial medial anterior meniscectomy. At 6 weeks postoperatively, OA was examined in five individual subregions of the medial tibial plateau using Kellgren-Lawrence grading, quantification of macroscopic OA, semiquantitative histopathological OA and immunohistochemical type-II collagen, ADAMTS-5, and MMP-13 scoring, biochemical determination of DNA and proteoglycan contents, and micro-computed tomographic evaluation of the subchondral bone., Results: Multivariate analyses revealed that OA cartilaginous changes had a temporal priority over subchondral bone changes. Underload inhibited early cartilage degeneration in a characteristic topographic pattern (P ≥ 0.0983 vs. normal), in particular below the meniscal damage, avoided alterations of the subarticular spongiosa (P ≥ 0.162 vs. normal), and prevented the disturbance of otherwise normal osteochondral correlations. Overload induced early alterations of the subchondral bone plate microstructure towards osteopenia, including significantly decreased percent bone volume and increased bone surface-to-volume ratio (all P ≤ 0.0359 vs. normal)., Conclusion: The data provide high-resolution evidence that tibiofemoral alignment modulates early OA induced by a medial meniscus injury in adult sheep. Since underload inhibits early OA, these data also support the clinical value of strategies to reduce the load in an affected knee compartment to possibly decelerate structural OA progression., Competing Interests: Competing interests H.M. received grants from DFG (German Research Foundation), Deutsche Arthrose-Hilfe, Deutsche Gesellschaft für Orthopädie und Orthopädische Chirurgie, Sorbonne University Paris, and Fidia farmaceutici S.p.A., speaker fees, and travel fees from Novartis and Fidia farmaceutici S.p.A., is a member of the Scientific Advisory Board of Thuasne and Bone therapeutics and received travel fees and was a member of the Scientific Advisory Board of Kolon TissueGene. All other authors declare no competing interests., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background: Restoration of osteochondral defects is critical, because osteoarthritis (OA) can arise., Hypothesis: Overexpression of insulin-like growth factor 1 (IGF-1) via recombinant adeno-associated viral (rAAV) vectors (rAAV-IGF-1) would improve osteochondral repair and reduce parameters of early perifocal OA in sheep after 6 months in vivo., Study Design: Controlled laboratory study., Methods: Osteochondral defects were created in the femoral trochlea of adult sheep and treated with rAAV-IGF-1 or rAAV- lacZ (control) (24 defects in 6 knees per group). After 6 months in vivo, osteochondral repair and perifocal OA were assessed by well-established macroscopic, histological, and immunohistochemical scoring systems as well as biochemical and micro-computed tomography evaluations., Results: Application of rAAV-IGF-1 led to prolonged (6 months) IGF-1 overexpression without adverse effects, maintaining a significantly superior overall cartilage repair, together with significantly improved defect filling, extracellular matrix staining, cellular morphology, and surface architecture compared with rAAV- lacZ . Expression of type II collagen significantly increased and that of type I collagen significantly decreased. Subchondral bone repair and tidemark formation were significantly improved, and subchondral bone plate thickness and subarticular spongiosa mineral density returned to normal. The OA parameters of perifocal structure, cell cloning, and matrix staining were significantly better preserved upon rAAV-IGF-1 compared with rAAV- lacZ . Novel mechanistic associations between parameters of osteochondral repair and OA were identified., Conclusion: Local rAAV-mediated IGF-1 overexpression enhanced osteochondral repair and ameliorated parameters of perifocal early OA., Clinical Relevance: IGF-1 gene therapy may be beneficial in repair of focal osteochondral defects and prevention of perifocal OA., Competing Interests: One or more of the authors has declared the following potential conflict of interest or source of funding: This work was funded by Deutsche Arthrose-Hilfe e.V. P229-A15-Madry-EP1-madr7-allgemein-pr-I-226k-2010-14 (M.C., H.M.). AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto.

Purpose: Elucidating subchondral bone remodeling in preclinical models of traumatic meniscus injury may address clinically relevant questions about determinants of knee osteoarthritis (OA)., Methods: Studies on subchondral bone remodeling in larger animal models applying meniscal injuries as standardizing entity were systematically analyzed. Of the identified 5367 papers reporting total or partial meniscectomy, meniscal transection or destabilization, 0.4% (in guinea pigs, rabbits, dogs, minipigs, sheep) remained eligible., Results: Only early or mid-term time points were available. Larger joint sizes allow reporting higher topographical details. The most frequently reported parameters were BV/TV (61%), BMD (41%), osteophytes (41%) and subchondral bone plate thickness (39%). Subchondral bone plate microstructure is not comprehensively, subarticular spongiosa microstructure is well characterized. The subarticular spongiosa is altered shortly before the subchondral bone plate. These early changes involve degradation of subarticular trabecular elements, reduction of their number, loss of bone volume and reduced mineralization. Soon thereafter, the previously normal subchondral bone plate becomes thicker. Its porosity first increases, then decreases., Conclusion: The specific human topographical pattern of a thinner subchondral bone plate in the region below both menisci is present solely in the larger species (partly in rabbits), but absent in rodents, an important fact to consider when designing animal studies examining subchondral consequences of meniscus damage. Large animal models are capable of providing high topographical detail, suggesting that they may represent suitable study systems reflecting the clinical complexities. For advanced OA, significant gaps of knowledge exist. Future investigations assessing the subchondral bone in a standardized fashion are warranted., (© 2023. The Author(s).)

Articular cartilage defects represent an unsolved clinical challenge. Photopolymerizable hydrogels are attractive candidates supporting repair. This study investigates the short-term safety and efficacy of two novel hyaluronic acid (HA)-triethylene glycol (TEG)-coumarin hydrogels photocrosslinked in situ in a clinically relevant large animal model. It is hypothesized that HA-hydrogel-augmented microfracture (MFX) is superior to MFX in enhancing early cartilage repair, and that the molar degree of substitution and concentration of HA affects repair. Chondral full-thickness defects in the knees of adult minipigs are treated with either 1) debridement (No MFX), 2) debridement and MFX, 3) debridement, MFX, and HA hydrogel (30% molar derivatization, 30 mg mL -1 HA; F3) (MFX+F3), and 4) debridement, MFX, and HA hydrogel (40% molar derivatization, 20 mg mL -1 HA; F4) (MFX+F4). After 8 weeks postoperatively, MFX+F3 significantly improves total macroscopic and histological scores compared with all other groups without negative effects, besides significantly enhancing the individual repair parameters "defect architecture," "repair tissue surface" (compared with No MFX, MFX), and "subchondral bone" (compared with MFX). These data indicate that photopolymerizable HA hydrogels enable a favorable metastable microenvironment promoting early chondrogenesis in vivo. This work also uncovers a mechanism for effective HA-augmented cartilage repair by combining lower molar derivatization with higher concentrations., (© 2023 The Authors. Advanced Healthcare Materials published by Wiley-VCH GmbH.)

Osteoarthritis (OA) is characterized by critical alterations of the subchondral bone microstructure, besides the well-known cartilaginous changes. Clinical computed tomography (CT) detection of quantitative 3D microstructural subchondral bone parameters is applied to monitor changes of subchondral bone structure in different stages of human OA and is compared with micro-CT, the gold standard. Determination by clinical CT (287 µm resolution) of key microstructural parameters in tibial plateaus with mild-to-moderate and severe OA reveals strong correlations to micro-CT (35 µm), high inter- and intraobserver reliability, and small relative differences. In vivo, normal, mild-to-moderate, and severe OA are compared with clinical CT (331 µm). All approaches detect characteristic expanded trabecular structure in severe OA and fundamental microstructural correlations with clinical OA stage. Multivariate analyses at various in vivo and ex vivo imaging resolutions always reliably separate mild-to-moderate from severe OA (except mild-to-moderate OA from normal), revealing a striking similarity between 287 µm clinical and 35 µm micro-CT. Thus, accurate structural measurements using clinical CT with a resolution near the trabecular dimensions are possible. Clinical CT offers an opportunity to quantitatively monitor subchondral bone microstructure in clinical and experimental settings as an advanced tool of investigating OA and other diseases affecting bone architecture., (© 2022 The Authors. Advanced Science published by Wiley-VCH GmbH.)

Although osteoarthritis (OA), a leading cause of disability, has been associated with joint malalignment, scientific translational evidence for this link is lacking. In a clinical case study, we provide evidence of osteochondral recovery upon unloading symptomatic isolated medial tibiofemoral knee OA associated with varus malalignment. By mapping response correlations at high resolution, we identify spatially complex degenerative changes in cartilage after overloading in a clinically relevant ovine model. We further report that unloading diminishes OA cartilage degeneration and alterations of critical parameters of the subchondral bone plate in a similar topographic fashion. Last, therapeutic unloading shifted the articular cartilage and subchondral bone phenotype to normal and restored several physiological correlations disturbed in neutral and varus OA, suggesting a protective effect on the integrity of the entire osteochondral unit. Collectively, these findings identify modifiable trajectories with considerable translational potential to reduce the burden of human OA.

Obscurin is a giant sarcomeric protein expressed in striated muscles known to establish several interactions with other proteins of the sarcomere, but also with proteins of the sarcoplasmic reticulum and costameres. Here, we report experiments aiming to better understand the contribution of obscurin to skeletal muscle fibers, starting with a detailed characterization of the diaphragm muscle function, which we previously reported to be the most affected muscle in obscurin ( Obscn ) KO mice. Twitch and tetanus tension were not significantly different in the diaphragm of WT and Obscn KO mice, while the time to peak (TTP) and half relaxation time (HRT) were prolonged. Differences in force-frequency and force-velocity relationships and an enhanced fatigability are observed in an Obscn KO diaphragm with respect to WT controls. Voltage clamp experiments show that a sarcoplasmic reticulum's Ca 2+ release and SERCA reuptake rates were decreased in muscle fibers from Obscn KO mice, suggesting that an impairment in intracellular Ca 2+ dynamics could explain the observed differences in the TTP and HRT in the diaphragm. In partial contrast with previous observations, Obscn KO mice show a normal exercise tolerance, but fiber damage, the altered sarcomere ultrastructure and M-band disarray are still observed after intense exercise.

Appropriate organization of cytoskeletal components are required for normal distribution and intracellular localization of different ion channels and proteins involved in calcium homeostasis, signal transduction, and contractile function of striated muscle. Proteins of the contractile system are in direct or indirect connection with the extrasarcomeric cytoskeleton. A number of other molecules which have essential role in regulating stretch-, voltage-, and chemical signal transduction from the surface into the cytoplasm or other intracellular compartments are already well characterized. Sarcomere, the basic contractile unit, is comprised of a precisely organized system of thin (actin), and thick (myosin) filaments. Intermediate filaments connect the sarcomeres and other organelles (mitochondria and nucleus), and are responsible for the cellular integrity. Interacting proteins have a very diverse function in coupling of the intracellular assembly components and regulating the normal physiological function. Despite the more and more intense investigations of a new cytoskeletal protein family, the septins, only limited information is available regarding their expression and role in striated, especially in skeletal muscles. In this review we collected basic and specified knowledge regarding this protein group and emphasize the importance of this emerging field in skeletal muscle biology., (© 2020. The Author(s).)

Background: The human knee is a complex joint, and affected by a variety of articular cartilage disorders. Large animal models are critical to model the complex disease mechanisms affecting a functional joint. Species-dependent differences highly affect the results of a pre-clinical study and need to be considered, necessitating specific knowledge not only of macroscopic and microscopic anatomical and pathological aspects, but also characteristics of their individual gait and joint movements., Methods: Literature search in Pubmed., Results and Discussion: This narrative review summarizes the most relevant anatomical structural and functional characteristics of the knee (stifle) joints of the major translational large animal species, comprising dogs, (mini)pigs, sheep, goats, and horses in comparison with humans. Specific characteristics of each species, including kinematical gait parameters are provided. Considering these multifactorial dimensions will allow to select the appropriate model for answering the research questions in a clinically relevant fashion., (Copyright © 2021 Elsevier GmbH. All rights reserved.)

Background: Small animal models are critical to model the complex disease mechanisms affecting a functional joint leading to articular cartilage disorders. They are advantageous for several reasons and significantly contributed to the understanding of the mechanisms of cartilage diseases among which osteoarthritis., Methods: Literature search in Pubmed., Results and Discussion: This narrative review summarizes the most relevant anatomical structural and functional characteristics of the knee (stifle) joints of the major small animal species, including mice, rats, guinea pigs, and rabbits compared with humans. Specific characteristics of each species, including kinematical gait parameters are provided and compared with the human situation. When placed in a proper context respecting their challenges and limitations, small animal models are important and appropriate models for articular cartilage disorders., (Copyright © 2020 Elsevier GmbH. All rights reserved.)

Osteoarthritis (OA) is considerably affected by joint alignment. Here, we investigate the patterns of spatial osteochondral heterogeneity in patients with advanced varus knee OA together with clinical data. We report strong correlations of osteochondral parameters within individual topographical patterns, highlighting their fundamental and location-dependent interactions in OA. We further identify site-specific effects of varus malalignment on the lesser loaded compartment and, conversely, an unresponsive overloaded compartment. Last, we trace compensatory mechanisms to the overloaded subarticular spongiosa in patients with additional high body weight. We therefore propose to consider and to determine axial alignment in clinical trials when selecting the location to assess structural changes in OA. Together, these findings broaden the scientific basis of therapeutic load redistribution and weight loss in varus knee OA., (Copyright © 2020 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.)

During aging reduction in muscle mass (sarcopenia) and decrease in physical activity lead to partial loss of muscle force and increased fatigability. Deficiency in the essential trace element selenium might augment these symptoms as it can cause muscle pain, fatigue, and proximal weakness. Average voluntary daily running, maximal twitch and tetanic force, and calcium release from the sarcoplasmic reticulum (SR) decreased while reactive oxygen species (ROS) production associated with tetanic contractions increased in aged - 22-month-old - as compared to young - 4-month-old - mice. These changes were accompanied by a decline in the ryanodine receptor type 1 (RyR1) and Selenoprotein N content and the increased amount of a degraded RyR1. Both lifelong training and selenium supplementation, but not the presence of an increased muscle mass at young age, were able to compensate for the reduction in muscle force and SR calcium release with age. Selenium supplementation was also able to significantly enhance the Selenoprotein N levels in aged mice. Our results describe, for the first time, the beneficial effects of selenium supplementation on calcium release from the SR and muscle force in old age while point out that increased muscle mass does not improve physical performance with aging.

Background: In vitro chondrogenesis depends on the concerted action of numerous signalling pathways, many of which are sensitive to the changes of intracellular Ca 2+ concentration. N-methyl-D-aspartate (NMDA) glutamate receptor is a cation channel with high permeability for Ca 2+ . Whilst there is now accumulating evidence for the expression and function of NMDA receptors in non-neural tissues including mature cartilage and bone, the contribution of glutamate signalling to the regulation of chondrogenesis is yet to be elucidated., Methods: We studied the role of glutamatergic signalling during the course of in vitro chondrogenesis in high density chondrifying cell cultures using single cell fluorescent calcium imaging, patch clamp, transient gene silencing, and western blotting., Results: Here we show that key components of the glutamatergic signalling pathways are functional during in vitro chondrogenesis in a primary chicken chondrogenic model system. We also present the full glutamate receptor subunit mRNA and protein expression profile of these cultures. This is the first study to report that NMDA-mediated signalling may act as a key factor in embryonic limb bud-derived chondrogenic cultures as it evokes intracellular Ca 2+ transients, which are abolished by the GluN2B subunit-specific inhibitor ifenprodil. The function of NMDARs is essential for chondrogenesis as their functional knock-down using either ifenprodil or GRIN1 siRNA temporarily blocks the differentiation of chondroprogenitor cells. Cartilage formation was fully restored with the re-expression of the GluN1 protein., Conclusions: We propose a key role for NMDARs during the transition of chondroprogenitor cells to cartilage matrix-producing chondroblasts.

Articular cartilage damage occurring during early osteoarthritis (OA) is a key event marking the development of the disease. Here, we modeled early human OA by gathering detailed spatiotemporal data from surgically induced knee OA development in sheep. We identified a specific topographical pattern of osteochondral changes instructed by a defined meniscal injury, showing that both cartilage and subchondral bone degeneration are initiated from the region adjacent to the damage. Alterations of the subarticular spongiosa arising locally and progressing globally disturbed the correlations of cartilage with subchondral bone seen at homeostasis and were indicative of disease progression. We validated our quantitative findings against human OA, showing a similar pattern of early OA correlating with regions of meniscal loss and an analogous late critical disturbance within the entire osteochondral unit. This translational model system can be used to elucidate mechanisms of OA development and provides a roadmap for investigating regenerative therapies., (Copyright © 2019 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.)

Small Ankyrins (sAnk1) are muscle-specific isoforms generated by the Ank1 gene that participate in the organization of the sarcoplasmic reticulum (SR) of striated muscles. Accordingly, the volume of SR tubules localized around the myofibrils is strongly reduced in skeletal muscle fibers of 4- and 10-month-old sAnk1 knockout (KO) mice, while additional structural alterations only develop with aging. To verify whether the lack of sAnk1 also alters intracellular Ca 2+ handling, cytosolic Ca 2+ levels were analyzed in stimulated skeletal muscle fibers from 4- and 10-month-old sAnk1 KO mice. The SR Ca 2+ content was reduced in sAnk1 KO mice regardless of age. The amplitude of the Ca 2+ transients induced by depolarizing pulses was decreased in myofibers of sAnk1 KO with respect to wild type (WT) fibers, while their voltage dependence was not affected. Furthermore, analysis of spontaneous Ca 2+ release events (sparks) on saponin-permeabilized muscle fibers indicated that the frequency of sparks was significantly lower in fibers from 4-month-old KO mice compared to WT. Furthermore, both the amplitude and spatial spread of sparks were significantly smaller in muscle fibers from both 4- and 10-month-old KO mice compared to WT. These data suggest that the absence of sAnk1 results in an impairment of SR Ca 2+ release, likely as a consequence of a decreased Ca 2+ store due to the reduction of the SR volume in sAnk1 KO muscle fibers.

Possible failures of autologous chondrocyte implantation (ACI), a cell-based technique for articular cartilage repair, are not always clinically apparent and the underlying mechanisms largely remain unknown. This case report presents the first scenario in the literature highlighting an association of a medium-term partial failure of an advanced ACI procedure (matrix-assisted ACI) in the knee with focal asymptomatic calcium pyrophosphate deposition disease, a common inflammatory pyrophosphate arthropathy. The specific presence of CPPDs, resulting from increased biomechanical stresses in the repair tissue-cartilage and repair tissue-subchondral bone integration sites, together with the absence of cartilage regeneration was identified and possibly contributed to the partial failure.Level of evidence V.

Background: In periarrest situations and during resuscitation it is essential to rule out reversible causes. Hyperkalemia is one of the most common, reversible causes of periarrest situations. Typical electrocardiogram (ECG) alterations may indicate hyperkalemia. The aim of our study was to compare the prevalence of ECG alterations suggestive of hyperkalemia in normokalemic and hyperkalemic patients., Methods: 170 patients with normal potassium (K + ) levels and 135 patients with moderate (serum K + = 6.0-7.0 mmol/l) or severe (K + > 7.0 mmol/l) hyperkalemia, admitted to the Department of Emergency Medicine at the Somogy County Kaposi Mór General Hospital, were selected for this retrospective, cross-sectional study. ECG obtained upon admission were analyzed by two emergency physicians, independently, blinded to the objectives of the study. Statistical analysis was performed using SPSS22 software. χ 2 test and Fischer exact tests were applied., Results: 24% of normokalemic patients and 46% of patients with elevated potassium levels had some kind of ECG alteration suggestive of hyperkalemia. Wide QRS (31.6%), peaked T-waves (18.4%), Ist degree AV-block (18.4%) and bradycardia (18.4%) were the most common and significantly more frequent ECG alterations suggestive of hyperkalemia in severely hyperkalemic patients compared with normokalemic patients (8.2, 4.7, 7.1 and 6.5%, respectively). There was no significant difference between the frequency of ECG alterations suggestive of hyperkalemia in normokalemic and moderately hyperkalemic patients. Upon examining ECG alterations not typically associated with hyperkalemia, we found that prolonged QTc was the only ECG alteration which was significantly more prevalent in both patients with moderate (17.5%) and severe hyperkalemia (21.1%) compared to patients with normokalemia (5.3%)., Conclusions: A minority of patients with normal potassium levels may also exhibit ECG alterations considered to be suggestive of hyperkalemia, while more than half of the patients with hyperkalemia do not have ECG alterations suggesting hyperkalemia. These results imply that treatment of hyperkalemia in the prehospital setting should be initiated with caution. Multiple ECG alterations, however, should draw attention to potentially life threatening conditions.

Besides their protective role, polyamines also serve as signalling molecules. However, further studies are needed to elucidate the polyamine signalling pathways, especially to identify polyamine-regulated mechanisms and their connections with other regulatory molecules. Reduced height (Rht) genes in wheat are often used in breeding programs to increase harvest index. Some of these genes are encoding DELLA proteins playing role in gibberellic acid signalling. The aim of the present paper was to reveal how the mutations in Rht gene modify the polyamine-regulated processes in wheat. Wild type and two Rht mutant genotypes (Rht 1: semi-dwarf; Rht 3: dwarf mutants) were treated with polyamines. Polyamine treatments differently influenced the polyamine metabolism, the plant growth parameters and certain hormone levels (salicylic acid and abscisic acid) in these genotypes. The observed distinct metabolism of Rht 3 may more likely reflect more intensive polyamine exodus from putrescine to spermidine and spermine, and the catabolism of the higher polyamines. The lower root to shoot translocation of putrescine can contribute to the regulation of polyamine pool, which in turn may be responsible for the observed lack of growth inhibition in Rht 3 after spermidine and spermine treatments. Lower accumulation of salicylic acid and abscisic acid, plant hormones usually linked with growth inhibition, in leaves may also be responsible for the diminished negative effect of higher polyamines on the shoot growth parameters observed in Rht 3. These results provide an insight into the role of polyamines in plant growth regulation based on the investigation of gibberellin-insensitive Rht mutants., (Copyright © 2019 Elsevier Masson SAS. All rights reserved.)

Accumulating evidence supports the role of astrocytes in endocannabinoid mediated modulation of neural activity. It has been reported that some astrocytes express the cannabinoid type 1 receptor (CB 1 -R), the activation of which is leading to Ca 2+ mobilization from internal stores and a consecutive release of glutamate. It has also been documented that astrocytes have the potential to produce the endocannabinoid 2-arachidonoylglycerol, one of the best known CB 1 -R agonist. However, no relationship between CB 1 -R activation and 2-arachidonoylglycerol production has ever been demonstrated. Here we show that rat spinal astrocytes co-express CB 1 -Rs and the 2-arachidonoylglycerol synthesizing enzyme, diacylglycerol lipase-alpha in close vicinity to each other. We also demonstrate that activation of CB 1 -Rs induces a substantial elevation of intracellular Ca 2+ concentration in astrocytes. Finally, we provide evidence that the evoked Ca 2+ transients lead to the production of 2-arachidonoylglycerol in cultured astrocytes. The results provide evidence for a novel cannabinoid induced endocannabinoid release mechanism in astrocytes which broadens the bidirectional signaling repertoire between astrocytes and neurons.

We report a severe envenoming associated with minimal local symptoms following a Balkan adder (Vipera berus bosniensis) bite in South-Western Hungary. A 63-year-old male with a history of hypertension and sinus bradycardia (45/min) was bitten by a sub-adult specimen of V. b. bosniensis in Somogy County on 04 May 2017. The patient was transported to and treated at the Emergency Department of "Moritz Kaposi" General Hospital, Kaposvár. Locally only pain and minimal swelling with a small haematoma developed on the bitten finger. The abdominal muscles were very tender and guarding was detected upon palpation on the way to hospital. The patient, who had taken his telmisartan (80 mg) tablet in that morning, complained of nausea and dizziness during the first medical examination. The systemic signs included fluctuations in blood pressure (115/85-165/105 mmHg), ECG changes (transient horizontal ST depression in V5-6, and sinus tachycardia (90/min)), severe diarrhoea and vomiting (in 7 episodes). Descending neuromuscular paralysis appeared in the next morning, including complete bilateral ptosis with external ophthalmoplegia, and binocular diplopia. Single-fiber electromyography confirmed the neuromuscular block in the frontalis muscle innervated by the facial nerve. Intense dizziness with uncoordinated movement emerged on the 3rd day. The laboratory findings were mild, including anaemia, hypokalaemia, elevated glutamic-pyruvic transaminase and C-reactive protein levels. The absolute neutrophil count remained almost completely normal. Supportive care and monovalent antivenom (Viper Venom Antitoxin ® , Biomed, Warsaw) were applied. The patient was discharged from hospital on the 4th day, although recovery was not complete until 9 days after the bite. This is the first photographically-documented case of neurotoxic envenoming from the South-Western Hungarian distribution range of V. b. bosniensis., (Copyright © 2018 Elsevier Ltd. All rights reserved.)