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Background: Large osteochondral lesions of the humeral head can result from locked posterior dislocations, avascular necrosis, and osteochondritis dissecans. Fresh osteochondral allograft (OCA) transplantation is a treatment option for young patients with focal osteochondral defects of the humeral head. The purpose of this case series was to assess graft survivorship, subjective patient-reported outcomes, and satisfaction among 7 patients who underwent OCA transplantation of the humeral head. Methods: We identified 7 patients who underwent humeral head OCA transplantation between 2008 and 2017. A custom questionnaire including the American Shoulder and Elbow Surgeons score, Quick Disabilities of the Arm, Shoulder, and Hand score (QuickDash), Likert satisfaction, and reoperations was mailed to each patient. Clinical failure was defined as further surgery that involved removal of the allograft. Results: Median follow-up duration was 10 years (range, 4.6 to 13.5 years) with a median age of 21.6 years (range, 18.5 to 43.5 years). Most patients (86%) reported improved function and reduced pain. At the final follow-up, 71% of patients reported ongoing problems with their shoulder including pain, stiffness, clicking/grinding, limited range of motion, and instability. Return to recreational activities was high at 86% but 43% expressed limitations with activity due to their shoulder. Overall satisfaction was high at 71% with mean American Shoulder and Elbow Surgeons and QuickDASH scores at 62.4 and 29.2, respectively. Reoperation after OCA occurred in 1 patient (14%). Conclusion: Among this case series of 7 patients who underwent OCA transplantation of the humeral head, patient satisfaction was high at 10-year follow-up and most returned to recreational activity although most also had persistent shoulder symptoms.

Abstract Background Glyphosate is a broad-spectrum, non-selective systemic herbicide with a commonly assumed low potential for accumulation in biota. Nevertheless, glyphosate has been shown to bioaccumulate in the tissues of several organisms. To understand the bioconcentration dynamics of glyphosate in fish, brown trout (Salmo trutta forma fario) of different age were exposed to different concentrations of glyphosate, the formulation Roundup® LB Plus, and the major transformation product aminomethylphosphonic acid (AMPA) for two, three, or four weeks at different temperatures in the laboratory. Mortality rates were determined, and tissue samples were collected at the end of the experiment to ascertain concentrations of glyphosate and AMPA residues by liquid chromatography coupled to mass spectrometry (LC–MS/MS). Results Brown trout mortality during exposure to glyphosate or AMPA was considerably higher at 15 °C than at 7 °C. Also, a significant increase in glyphosate concentrations in samples containing muscle, head, backbone, and caudal fin tissue with increasing exposure concentrations and temperatures was observed. Six-month-old fish contained more glyphosate per kg wet weight after exposure than ten-month-old fish. The bioconcentration factors (BCFs) for glyphosate and AMPA were much higher at 15 °C than at 7 °C, but in both cases decreased with higher glyphosate concentrations. The BCF for glyphosate formulated in Roundup® was higher than the one for the parent compound. Approximately 30–42% of the organ-absorbed glyphosate and AMPA remained in the tissues even when the fish were kept in clean water lacking the test substances for three weeks after termination of exposure. Conclusion Our study demonstrated that there is an interaction between glyphosate and ambient temperature in terms of toxicity. Further it was shown that increasing concentrations of glyphosate and AMPA in the surrounding media lead to significantly increased concentrations of these substances in brown trout tissues, although neither bioconcentration nor bioaccumulation of glyphosate in animal tissues is expected due to the high water solubility of this chemical. As a consequence, the uptake of glyphosate by humans through the consumption of contaminated edible fish is very likely.

To elucidate how rising temperatures influence native amphipods, and how the expansion of wastewater treatment plants (WWTPs) with a fourth purification stage can alter temperature-related effects, studies were conducted in anthropogenically influenced rivers in Southwest Germany. Gammarids were sampled up- and downstream of two WWTPs, and exposed to elevated temperatures in the laboratory. Gammarids separated from precopula pairs were more sensitive to exposure-related stress and to a temperature increase than animals that were not in the reproductive phase. Furthermore, females were significantly more sensitive than males. Adult gammarids sampled individually at the WWTP with three purification stages showed a similar tolerance to elevated temperature at the up- and downstream site. In contrast, mortality following heat stress was substantially lower in animals sampled downstream of the WWTP with four treatment stages than in those sampled at the upstream site. We assume that the increased sensitivity of artificially separated precopula pairings reflect the situation under high hydraulic stress after heavy rainfall. Our results further illustrate the importance of WWTP upgrades in the context of climate change: gammarids sampled downstream the upgraded fourth-stage WWTP were likely exposed to lower levels of micropollutants, and thus may have allocated energy from detoxification to heat stress responses.

Metabolism, mainly driven by oxygen consumption, plays a key role in life, as it is one of the main ways to respond to extreme temperatures through internal processes. Theba pisana, a widespread Mediterranean land snail, is exposed to a wide range of ambient temperature. In this species the oxygen consumption was tested as a response variable by multiple regression modelling on the “explanatory” variables shell-free mass, temperature, and relative humidity. Our results show that the oxygen consumption of T. pisana can be well described (73.1%) by these three parameters. In the temperature range from 23 °C to 35 °C the oxygen consumption decreased with increasing temperature. Relative humidity, in the range of 67% to 100%, had the opposite effect: if it increases, oxygen consumption will increase as well. Metabolism is proportional to an individual’s mass to the power of the allometric scaling exponent α, which is between 0.62 and 0.77 in the mentioned temperature range. CT scans of shells and gravimetry revealed the shell-free mass to be calculated by multiplying the shell diameter to the third power by 0.2105. Data were compared to metabolic scaling exponents for other snails reported in the literature.

Abstract Coloration of animals is important for camouflage, for social behavior, or for physiological fitness. This study investigates the color variation in adults of Aglais urticae obtained on subjecting some pre‐imaginal stages to different temperature conditions and their thermobiological consequences. To investigate the evolutionary–ecological interactions of temperature and pigmentation in butterflies, caterpillars, and pupae of the small tortoiseshell, Aglais urticae (Lepidoptera, Nymphalidae), larvae from Central Europe and Scandinavia were reared at temperatures between 7 and 34°C in the laboratory or in the field. After emergence, the intensity of pigmentation of the imagines and their increase in body temperature under defined full‐spectrum light irradiation were quantified by image analysis and thermal imaging. At constant conditions, ambient rearing temperature and pigmentation intensity of imagines were negatively and linearly correlated in Central European butterflies, regardless of whether the pupal stage alone or, additionally, the last period of the larval stage was exposed to these conditions: low temperatures induced darker coloration and high temperatures led to lighter individuals. A thermal pulse of a few days alone at the beginning of pupal dormancy led to a similar, albeit weakened, effect. Caterpillars of the Scandinavian subspecies A. urticae polaris, whose pupal dormancy took place under Central European field conditions, developed into strongly pigmented imagines. The thermobiological relevance of more intense pigmentation was shown by significantly higher absorption of light, and thus stronger increased body temperature after 5 min of defined illumination, but this difference ceased after 15 min. Our results show that phenotypic plasticity in wing coloration is adaptive since temperature‐induced developmental changes provide thermobiological benefit in adult butterflies. We propose that, in subpolar latitudes, darker coloration likely has a selection advantage favoring individuals with reaction norms gradually shifted to stronger pigmented phenotypes, possibly leading to the establishment of a pigmentation cline.

Abstract In terrestrial snails, thermal selection acts on shell coloration. However, the biological relevance of small differences in the intensity of shell pigmentation and the associated thermodynamic, physiological, and evolutionary consequences for snail diversity within the course of environmental warming are still insufficiently understood. To relate temperature‐driven internal heating, protein and membrane integrity impairment, escape behavior, place of residence selection, water loss, and mortality, we used experimentally warmed open‐top chambers and field observations with a total of >11,000 naturally or experimentally colored individuals of the highly polymorphic species Theba pisana (O.F. MÜLLER, 1774). We show that solar radiation in their natural Mediterranean habitat in Southern France poses intensifying thermal stress on increasingly pigmented snails that cannot be compensated for by behavioral responses. Individuals of all morphs acted neither jointly nor actively competed in climbing behavior, but acted similarly regardless of neighbor pigmentation intensity. Consequently, dark morphs progressively suffered from high internal temperatures, oxidative stress, and a breakdown of the chaperone system. Concomitant with increasing water loss, mortality increased with more intense pigmentation under simulated global warming conditions. In parallel with an increase in mean ambient temperature of 1.34°C over the past 30 years, the mortality rate of pigmented individuals in the field is, currently, about 50% higher than that of white morphs. A further increase of 1.12°C, as experimentally simulated in our study, would elevate this rate by another 26%. For 34 T. pisana populations from locations that are up to 2.7°C warmer than our experimental site, we show that both the frequency of pigmented morphs and overall pigmentation intensity decrease with an increase in average summer temperatures. We therefore predict a continuing strong decline in the frequency of pigmented morphs and a decrease in overall pigmentation intensity with ongoing global change in areas with strong solar radiation.

Tire and road wear particles (TRWP), which contribute significantly to microplastic emission, are receiving more attention, but details about particle composition, translocation from source to sink, and particularly the possible effects on ecosystems are largely unknown. We examined the influence of native TRWP-containing sediments from two settling ponds on the mortality and behavior of the aquatic larvae of Chironomus riparius. Both sediments, whether pure or mixed with different proportions of quartz sand and suspended in water, led to increased mortalities with increasing concentrations and were shown to be oxygen consuming. Artificial aeration significantly reduced larval mortality in both sediments. Chironomid larvae show high tolerance to anoxic and polluted environments due to physiological and behavioral adaptations, such as the construction of vertical sediment tubes (chimneys), in which they create oxic compartments. A significant correlation was found between the proportion of contaminated sediment and the number of chimneys: the more contaminated sediment, the fewer chimneys were constructed. The number of chimneys per surviving larva decreased with an increased proportion of contaminated sediment in parallel to increased larval mortality. We hypothesize that contents of these sediments negatively impact the larvae’s ability to survive at low oxygen concentrations due to impairments of essential behavioral and physiological processes.

Background: Thoracic outlet syndrome (TOS) remains a rare diagnosis but is being recognized as a cause of upper extremity dysfunction in professional baseball players. Purpose/Hypothesis: The purpose was to determine performance and return-to-play (RTP) outcomes in professional baseball players after surgical treatment of TOS. The hypothesis was that there would be a high RTP rate in professional baseball players after TOS surgery with no statistical differences in performance between pitchers who had TOS surgery and matched controls. Study Design: Cohort study; Level of evidence, 3. Methods: All professional baseball players who underwent surgical treatment of TOS between 2010 and 2017 were identified using the Major League Baseball Health and Injury Tracking System database. Demographic and performance data (before and after surgery) for each player were recorded. Performance variables were then compared between players who underwent TOS surgery and matched controls. The matching criteria were no history of previous surgeries on affected arm, age at time of surgery, throwing side, level of play (Major or Minor League Baseball), and years of experience playing professional baseball. Results: Overall, 52 players underwent surgery for TOS, of whom 46 (88%) were pitchers. The type of TOS was neurogenic in 69% and venous in 29%. One player had arterial TOS. After TOS surgery, 79% of players returned to play at the same or higher level (RTSP) by 9.5 months and played ≥3 years after surgery. No differences were found in RTSP rate based on the type of TOS. No statistical difference was found in RTP rates between major and minor league players. Pitchers had a 76% RTSP, which was similar to the natural attrition for control pitchers (P =.874). After TOS surgery, pitchers saw a decline in several performance metrics, but these declines were not different from those of control pitchers, indicating that the decline in performance after TOS surgery was no faster than is seen in healthy professional pitchers as they age. Conclusion: The rate of RTSP after surgery for TOS in professional baseball players was 79%. There was no difference in RTP based on the type of TOS. Pitchers who underwent surgery for TOS had no significant differences in pitching performance metrics after surgery compared with matched controls. [ABSTRACT FROM AUTHOR]

Abstract Terrestrial gastropods do not only inhabit humid and cool environments but also habitat in which hot and dry conditions prevail. Snail species that are able to cope with such climatic conditions are thus expected to having developed multifaceted strategies and mechanisms to ensure their survival and reproduction under heat and desiccation stress. This review paper aims to provide an integrative overview of the numerous adaptation strategies terrestrial snails have evolved to persist in hot and dry environments as well as their mutual interconnections and feedbacks, but also to outline research gaps and questions that remained unanswered. We extracted relevant information from more than 140 publications in order to show how biochemical, cellular, physiological, morphological, ecological, thermodynamic, and evolutionary parameters contribute to provide an overall picture of this classical example in stress ecology. These mechanisms range from behavioral and metabolic adaptations, including estivation, to the induction of chaperones and antioxidant enzymes, mucocyte and digestive gland cell responses and the modification and frequency of morphological features, particularly shell pigmentation. In this context, thermodynamic constraints call for processes of complex adaptation at varying levels of biological organization that are mutually interwoven. We were able to assemble extensive, mostly narrowly focused information from the literature into a web of network parameters, showing that future work on this subject requires multicausal thinking to account for the complexity of relationships involved in snails' adaptation to insolation, heat, and drought.

Pharmaceuticals such as antidepressants are designed to be bioactive at low concentrations. According to their mode of action, they can also influence non-target organisms due to the phylogenetic conservation of molecular targets. In addition to the pollution by environmental chemicals, the topic of microplastics (MP) in the aquatic environment came into the focus of scientific and public interest. The aim of the present study was to investigate the influence of the antidepressant amitriptyline in the presence and absence of irregularly shaped polystyrene MP as well as the effects of MP alone on juvenile brown trout (Salmo trutta f. fario). Fish were exposed to different concentrations of amitriptyline (nominal concentrations between 1 and 1000 µg/L) and two concentrations of MP (104 and 105 particles/L;

Abstract Background Due to the rising number of type 2 diabetes patients, the antidiabetic drug, metformin is currently among those pharmaceuticals with the highest consumption rates worldwide. Via sewage-treatment plants, metformin enters surface waters where it is frequently detected in low concentrations (µg/L). Since possible adverse effects of this substance in aquatic organisms have been insufficiently explored to date, the aim of this study was to investigate the impact of metformin on health and development in brown trout (Salmo trutta f. fario) and its microbiome. Results Brown trout embryos were exposed to 0, 1, 10, 100 and 1000 µg/L metformin over a period from 48 days post fertilisation (dpf) until 8 weeks post-yolk sac consumption at 7 °C (156 dpf) and 11 °C (143 dpf). Chemical analyses in tissues of exposed fish showed the concentration-dependent presence of metformin in the larvae. Mortality, embryonic development, body length, liver tissue integrity, stress protein levels and swimming behaviour were not influenced. However, compared to the controls, the amount of hepatic glycogen was higher in larvae exposed to metformin, especially in fish exposed to the lowest metformin concentration of 1 µg/L, which is environmentally relevant. At higher metformin concentrations, the glycogen content in the liver showed a high variability, especially for larvae exposed to 1000 µg/L metformin. Furthermore, the body weight of fish exposed to 10 and 100 µg/L metformin at 7 °C and to 1 µg/L metformin at 11 °C was decreased compared with the respective controls. The results of the microbiome analyses indicated a shift in the bacteria distribution in fish exposed to 1 and 10 µg/L metformin at 7 °C and to 100 µg/L metformin at 11 °C, leading to an increase of Proteobacteria and a reduction of Firmicutes and Actinobacteria. Conclusions Overall, weight reduction and the increased glycogen content belong to the described pharmaceutical effects of the drug in humans, but this study showed that they also occur in brown trout larvae. The impact of a shift in the intestinal microbiome caused by metformin on the immune system and vitality of the host organism should be the subject of further research before assessing the environmental relevance of the pharmaceutical.

During the last decades, depression has been diagnosed in increasing numbers, accompanied by rising prescription rates of antidepressants. Concomitantly, these pharmaceuticals are frequently detected in surface waters. Serotonin and noradrenalin reuptake inhibitors such as venlafaxine form the second largest group of antidepressants worldwide, and venlafaxine is the second most prescribed antidepressant in Germany. As drug targets are evolutionary highly conserved, venlafaxine can potentially change not only behavior and related physiological processes in humans but also in non-target species, especially aquatic organisms. In order to test this hypothesis for fish, we exposed brown trout larvae and juveniles to venlafaxine at concentrations ranging from 1 to 1,000 μg/L. Larvae were exposed for 5 months from the eyed ova stage until 8 weeks post yolk-sac consumption at 7 and 11 °C. Juveniles were exposed for 4 weeks at 7 °C. Mortality, weight, length, behavior during exposure and behavior in a stressful environment were recorded in both experiments. For larvae, additionally, hatching rate and heart rate were analyzed. In juvenile fish, tissue cortisol levels were determined. Our results clearly showed, that brown trout, irrespective of their life stage, change their behavior when being exposed to venlafaxine: During exposure, venlafaxine at 7 °C caused larvae to sojourn in the upper part of the aquaria for a longer time, with a lowest observed effect concentration of 100 μg/L. In a stressful environment with limited space, fish exposed to ≥10 μg/L venlafaxine were less active than controls. Furthermore, venlafaxine reduced the growth of larvae (length at ≥10 μg/L, weight at 1 mg/L) and their survival after 5 months (at 1 mg/L). Hatching rate and heart rate of larvae as well as tissue cortisol concentration of juveniles were not affected by venlafaxine treatment.

The present work gives insight into the internal heat management of the respiratory system in the terrestrial snail Xeropicta derbentina, which has to cope with extreme climate conditions in its habitat. A realistic model of the lung´s vein system was constructed and the active diffusive surface of capillaries and main vein was calculated and confirmed by geometrical measurements. We here present a model that is able to validate the measured oxygen consumption by the use of the Colburn analogy between mass and momentum transfer. By combining basic diffusion laws with the momentum transfer, i.e. wall shear stress, at the inner wall of the lung capillaries and the main vein, the progression of the oxygen mass fraction in the hemolymph can be visualized.

Background Over the last two decades, there has been a constant increase in prescription rates of antidepressants. In parallel, neuroactive pharmaceuticals are making their way into aquatic environments at increasing concentrations. Among the antidepressants detected in the environment citalopram, a selective serotonin reuptake inhibitor, is one of the most commonly found. Given citalopram is specifically designed to alter mood and behaviour in humans, there is growing concern it can adversely affect the behaviour on non-target wildlife Methods In our study, brown trout were exposed to citalopram (nominal concentrations: 1, 10, 100, 1000 µg/L) in two different life stages. Larvae were exposed at 7 and 11 °C from the eyed ova stage until 8 weeks post yolk sac consumption, and juvenile brown trout were exposed for 4 weeks at 7 °C. At both stages we measured mortality, weight, length, tissue citalopram concentration, behaviour during exposure and behaviour in a stressfull environment. For brown trout larvae additionally hatching rate and heart rate, and for juvenile brown trout the tissue cortisol concentration were assessed. Results During the exposure, both larvae and juvenile fish exposed to the highest test concentration of citalopram (1 mg/L) had higher swimming activity and spent longer in the upper part of the aquaria compared to control fish, which is an indicator for decreased anxiety. Most probably due to the higher swimming activity during the exposure, the juveniles and larvae exposed to 1 mg/L citalopram showed decreased weight and length. Additionally, in a stressful artificial swimming measurement device, brown trout larvae displayed the anxiolytic effect of the antidepressant by reduced swimming activity during this stress situation, already at concentrations of 100 µg/L citalopram. Chemical analysis of the tissue revealed rising citalopram tissue concentrations with rising exposure concentrations. Tissue concentrations were 10 times higher in juvenile fish compared to brown trout larvae. Fish plasma concentrations were calculated, which exceeded human therapeutic levels for the highest exposure concentration, matching the behavioural results. Developmental parameters like hatching rate and heart rate, as well as mortality and tissue cortisol content were unaffected by the antidepressant. Overall, we could trace the pharmacological mode of action of the antidepressant citalopram in the non-target organism brown trout in two different life stages.

Abstract Background In situ exposure of rainbow trout up- and downstream of differently equipped wastewater treatment plants (WWTPs) and subsequent analyses of micronuclei frequencies and hepatic EROD activities were used to evaluate the impact of the effluents on fish health. Two of the facilities (WWTPs A and B) were conventional treatment plants. WWTP C has been equipped with a powdered activated carbon stage. Here, analyses were conducted prior and subsequent to this upgrade. Results Differences did not only occur when comparing conventional (WWTPs A, B and C prior to the upgrade) and advanced treatment (WWTP C after the upgrade), but also between the conventionally equipped WWTPs. There was no indication for genotoxic effects or pollution-related EROD induction in fish exposed at WWTP A. In contrast, trout exposed at WWTP B expressed strong reactions. However, here, adverse reactions were also observed in fish kept upstream. Similar observations were made for EROD activities in fish exposed at WWTP C prior to the upgrade, whereas genotoxic effects could only be seen in trout kept downstream of this effluent. Upgrading of WWTP C resulted in a significant reduction of both genotoxic effects and EROD levels. Conclusions The results show financial investments in advanced wastewater treatment to be beneficial for aquatic ecosystems, especially when conventional technologies do not sufficiently remove pollutants. Yet, negative impacts of effluents on aquatic organisms can, under certain conditions, also be avoided by conventional treatment. Therefore, we recommend deciding on the necessity and the type of WWTP upgrading on a case-by-case basis.

Abstract Background Although the crucial importance of sediments in aquatic systems is well-known, sediments are often neglected as a factor in the evaluation of water quality assessment. To support and extend previous work in that field, this study was conducted to assess the impact of surface water and sediment on fish embryos in the case of a highly anthropogenically influenced river catchment in Central Hesse, Germany. Results The results of 96 h post fertilisation fish embryo toxicity test with Danio rerio (according to OECD Guideline 236) revealed that river samples comprising both water and sediment exert pivotal effects in embryos, whereas surface water alone did not. The most prominent reactions were developmental delays and, to some extent, malformations of embryos. Developmental delays occurred at rates up to 100% in single runs. Malformation rates ranged mainly below 10% and never exceeded 25%. Conclusion A clear relationship between anthropogenic point sources and detected effects could not be established. However, the study illustrates the critical condition of the entire river system with respect to embryotoxic potentials present even at the most upstream test sites. In addition, the study stresses the necessity to take into account sediments for the evaluation of ecosystem health in industrialised areas.

The global economic success of man-made nanoscale materials has led to a higher production rate and diversification of emission sources in the environment. For these reasons, novel nanosafety approaches to assess the environmental impact of engineered nanomaterials are required. While studying the potential toxicity of metal nanoparticles (NPs), we realized that gold nanoparticles (AuNPs) have a growth-promoting rather than a stress-inducing effect. In this study we established stable short- and long-term exposition systems for testing plant responses to NPs. Exposure of plants to moderate concentrations of AuNPs resulted in enhanced growth of the plants with longer primary roots, more and longer lateral roots and increased rosette diameter, and reduced oxidative stress responses elicited by the immune-stimulatory PAMP flg22. Our data did not reveal any detrimental effects of AuNPs on plants but clearly showed positive effects on growth, presumably by their protective influence on oxidative stress responses. Differential transcriptomics and proteomics analyses revealed that oxidative stress responses are downregulated whereas growth-promoting genes/proteins are upregulated. These omics datasets after AuNP exposure can now be exploited to study the underlying molecular mechanisms of AuNP-induced growth-promotion.

Depression is a serious health issue and, being such, treatment for it has become a topic of increasing concern. Consequently, the prescription rates of antidepressants have increased by about 50% over the past decade. Among antidepressants, citalopram and venlafaxine are the most frequently prescribed in Germany. Due to the high consumption and low elimination rates of both antidepressants during wastewater purification, they are frequently found in surface waters, where they may pose a risk to the aquatic environment. For the present study, we conducted experiments with the big ramshorn snail, which we exposed to environmentally relevant and explicitly higher concentrations (1–1000 µg/L) of the antidepressants citalopram and venlafaxine. We investigated apical endpoints, such as weight, mortality, behavioural changes, B-esterase activity, Hsp70 stress protein level and superoxide dismutase activity, as well as the tissue integrity of the hepatopancreas in the exposed snails. Citalopram and venlafaxine had no effects on the B-esterase activity, Hsp70 level and superoxide dismutase activity. Citalopram exposure resulted in weight reduction and tissue reactions in the hepatopancreas of snails exposed to 1000 µg/L. In contrast, venlafaxine did not induce comparable effects, but impacted the behaviour (sole detachment) of snails exposed to 100 µg/L and 1000 µg/L of the antidepressant. These results revealed that venlafaxine can affect snails at concentrations 10 times lower than citalopram. For this, in 2020 venlafaxine was introduced in the “Surface Water Watch List”, a list of potential pollutants that should be carefully monitored in surface water by the EU Member States.

Background Guanylurea is the main transformation product of the antidiabetic drug metformin, which is one of the most prescribed pharmaceuticals worldwide. Due to the high rate of microbial degradation of metformin in sewage treatment plants, guanylurea occurs in higher concentrations in surface waters than its parent compound and could therefore affect aquatic wildlife. In this context, data for fish are scarce up to now which made us investigate the health of brown trout (Salmo trutta f. fario) in response to guanylurea. Methods In two experiments, eggs plus developing larvae and juvenile brown trout were exposed to three different concentrations of guanylurea (10, 100 and 1,000 µg/L) and, as a negative control, filtered tap water without this compound. Low internal concentrations were determined. The investigated parameters were mortality, length, weight, condition factor, tissue integrity of the liver and kidney, levels of stress proteins and lipid peroxides, as well as behavioural and developmental endpoints. It was found that guanylurea did not significantly change any of these parameters in the tested concentration range. Results In conclusion, these results do not give rise to concern that guanylurea could negatively affect the health or the development of brown trout under field conditions. Nevertheless, more studies focusing on further parameters and other species are highly needed for a more profound environmental risk assessment of guanylurea.

Background Glyphosate is among the most extensively used pesticides worldwide. Following the ongoing highly controversial debate on this compound, its potential impact on non-target organisms is a fundamental scientific issue. In its pure compound form, glyphosate is known for its acidic properties. Methods We exposed zebrafish (Danio rerio) embryos to concentrations between 10 μM and 10 mM glyphosate in an unbuffered aqueous medium, as well as at pH 7, for 96 hours post fertilization (hpf). Furthermore, we investigated the effects of aqueous media in the range of pH 3 to 8, in comparison with 1 mM glyphosate treatment at the respective pH levels. Additionally, we exposed zebrafish to 7-deoxy-sedoheptulose (7dSh), another substance that interferes with the shikimate pathway by a mechanism analogous to that of glyphosate, at a concentration of one mM. The observed endpoints included mortality, the hatching rate, developmental delays at 24 hpf, the heart rate at 48 hpf and the malformation rate at 96 hpf. LC10/50, EC10 and, if reasonable, EC50 values were determined for unbuffered glyphosate. Results The results revealed high mortalities in all treatments associated with low pH, including high concentrations of unbuffered glyphosate (>500 μM), low pH controls and glyphosate treatments with pH < 3.4. Sublethal endpoints like developmental delays and malformations occurred mainly at higher concentrations of unbuffered glyphosate. In contrast, effects on the hatching rate became particularly prominent in treatments at pH 7, showing that glyphosate significantly accelerates hatching compared with the control and 7dSh, even at the lowest tested concentration. Glyphosate also affected the heart rate, resulting in alterations both at pH 7 and, even more pronounced, in the unbuffered system. In higher concentrations, glyphosate tended to accelerate the heart rate in zebrafish embryos, again, when not masked by the decelerating influence of its low pH. At pH > 4, no mortality occurred, neither in the control nor in glyphosate treatments. At 1 mM, 7dSh did not induce any mortality, developmental delays or malformations; only slightly accelerated hatching and a decelerated heart rate were observed. Our results demonstrate that lethal impacts in zebrafish embryos can be attributed mainly to low pH, but we could also show a pH-independent effect of glyphosate on the development of zebrafish embryos on a sublethal level.

In the present study, we investigated the efficiency of additional wastewater treatment based on powdered activated carbon and its benefit for the ecosystem of a connected river system in the catchment area of Lake Constance, Southern Germany. We focused on the overall health status of gammarids and the integrity of the macrozoobenthic community. Samples were taken up- and down-stream of a wastewater treatment plant (WWTP), as well as before and after its upgrading. The investigations showed that both sex ratio and fecundity of gammarids, as well as the macrozoobenthic community were affected by the effluent prior to the WWTP upgrade. After the upgrade, gammarids from the downstream site did not differ any longer from those collected upstream of the WWTP with respect to the investigated health parameters. Furthermore, the overall number of taxa and, particularly, the number of sensitive taxa within the macrozoobenthic community downstream of the WWTP increased considerably. Therefore, we conclude that the additional treatment with powdered activated carbon was highly efficient to improve invertebrate health and community integrity.

Pharmaceuticals can enter surface waters via sewage treatment plants. In the environment, the substances and their transformation products, formed by the degradation of the parent compounds, can affect aquatic wildlife, including freshwater invertebrates. However, research on pharmaceutical-induced effects in wild freshwater organisms other than fish is still scarce. In our study, we investigated the impact of the highly consumed antidiabetic drug metformin and its main transformation product, guanylurea, on the health of a freshwater gastropod—the big ramshorn snail (Planorbarius corneus) by analysing its biochemical and cellular stress responses and apical parameters. The snails were exposed to different concentrations of the drug (0, 0.01, 0.1, 1, and 10 mg/L) and its transformation product (0, 0.1, 10, and 100 mg/L). The examined parameters were mortality, weight, tissue integrity of the hepatopancreas, and the levels of stress proteins and lipid peroxides. Mortality and the levels of stress proteins and lipid peroxides were not influenced by the two substances. In response to the highest concentrations of both chemicals, the weight of the snails was slightly but not significantly reduced. The histopathological investigation of the hepatopancreas revealed a significant effect of guanylurea at a concentration of 100 mg/L with an increased number of symptoms of cellular responses in the tissue (e.g., dilated lumen, disturbed compartmentation of the digestive cells, nucleus deformation, hyperplasia, and hypertrophy of crypt cells). For the parent compound, a similar trend was also observed for the highest concentration. Overall, the observed effects did not occur at environmentally relevant concentrations, but at concentrations which were 10,000 times higher than these. Thus, the results did not give rise to a major concern that metformin and guanylurea could pose a risk to the big ramshorn snail in the environment.

A promising approach to overcome hypoxic conditions in tissue engineered constructs is to use the potential of endothelial cells (EC) to form networks in vitro when co-cultured with a supporting cell type in a 3D environment. Adipose tissue-derived stromal cells (ASC) as well as bone marrow-derived stromal cells (BMSC) have been shown to support vessel formation of EC in vitro, but only very few studies compared the angiogenic potential of both cell types using the same model. Here, we aimed at investigating the ability of ASC and BMSC to induce network formation of EC in a co-culture model in fibrin. While vascular structures of BMSC and EC remained stable over the course of 3 weeks, ASC-EC co-cultures developed more junctions and higher network density within the same time frame. Both co-cultures showed positive staining for neural glial antigen 2 (NG2) and basal lamina proteins. This indicates that vessels matured and were surrounded by perivascular cells as well as matrix molecules involved in stabilization. Gene expression analysis revealed a significant increase of vascular endothelial growth factor (VEGF) expression in ASC-EC co-culture compared to BMSC-EC co-culture. These observations were donor-independent and highlight the importance of organotypic cell sources for vascular tissue engineering.