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Although environmental DNA (eDNA) metabarcoding is an exceptionally useful and powerful tool for monitoring biodiversity, little is known about whether the traits of organisms and their ecosystem characteristics affect eDNA metabarcoding performance. Nationwide surveys can provide more detailed insights, yet such studies have rarely been conducted.In order to evaluate eDNA metabarcoding performance in broad‐scale monitoring, we examined the effects of species ecological/biological traits and ecosystem characteristics on species detection rates and the implications for community analysis. In addition, we tested the effects of sample mixing and transportation methods, including cooling and freezing, on eDNA metabarcoding. On a nationwide scale, we conducted eDNA metabarcoding for fish communities in 18 Japanese lakes.By comparing species records, we observed that certain traits, including body size, body shape, saltwater tolerance and habitat preference, influenced eDNA detection. In addition, the proportion of species detected decreased significantly with an increase in lake surface area owing to ecosystem size effect on species detection.We conclude that species traits, including habitat preference, body size and ecosystem size, should be considered when assessing the eDNA metabarcoding performance in broad‐scale monitoring. [ABSTRACT FROM AUTHOR]

This paper investigated the effects of grazing by Galerucella nipponensis (Coleoptera: Chrysomelidae) on growth and seed production of its host plant Trapa japonica (Trapaceae). A water tank experiment demonstrated that the new rosette leaves grazed upon by the beetles had a shorter life span than those of ungrazed rosettes. In ponds, severely grazed T. japonica rosettes produced more new leaves than slightly grazed rosettes. The period of seed production was delayed in years when leaves were severely grazed during the flowering seasons. Grazing peaked in later growing seasons when rosettes produce seeds. The ratio of seed production in the latter half of the peak to that in the early half was higher under severe grazing conditions than slight or moderate grazing conditions. A higher density of seeds in ponds in the current year tended to produce more abundant rosettes in the following spring. These results suggest that the herbivory of G. nipponensis induces compensatory reproduction of T. japonica in a complicated manner. [ABSTRACT FROM AUTHOR]

The spatial structure-mediated indirect effects of an aquatic host plant, Trapa japonica (Trapaceae), on survival of a leaf beetle, Galerucella nipponensis (Coleoptera: Chrysomelidae), with regard to predation by a water strider, Gerris nepalensis (Hemiptera: Gerridae), were investigated in an irrigation pond and under indoor conditions. Beetle density, particularly in the first-instar stage of the larvae, became extremely low in the second generation in the pond, even though food resources were abundant. The biological check method, which excludes natural enemies by caging, suggested that a causal factor of the low density was predation by Gerris nepalensis in midsummer and thereafter. Normally growing rosettes extend their leaves horizontally on the water surface. However, some rosettes of T. japonica grew leaves vertically in the later seasons, and such overgrown rosettes were distributed patchily in the ponds. Beetle density was higher on the latter rosettes than on the former ones. The indoor experiment showed that the water strider can feed on the eggs of beetles on normally grown rosettes but not on the overgrown rosettes. Furthermore, female adults of Galerucella nipponensis preferred the overgrown rosettes over the normally grown rosettes for oviposition when water striders were present. These facts suggest that the spatial structure-mediated indirect effects of the host plant modify the interaction between herbivore and predator. [ABSTRACT FROM AUTHOR]

Purpose: This study aims to elucidate changes in the tibiofemoral relationship over time following anterior cruciate ligament (ACL) injury, and investigate the correlation between the tibiofemoral relationship and patient‐related outcome measures (PROMs). Methods: Overall, 203 primary ACL reconstructions were performed using autologous hamstring grafts. Medial and lateral anterior tibial translation (ATT) in the sagittal plane and tibial tubercle‐trochlear groove (TT‐TG) distance in the axial plane were measured using pre‐operative magnetic resonance imaging and post‐operative computed tomography. The difference between pre‐operative and post‐operative values for each parameter was calculated: ΔMesdial ATT, ΔLateral ATT and ΔTT‐TG distance. The correlation between each calculated value and the time elapsed since ACL injury, and the correlation between each calculated value and PROMs—evaluated using the Knee Injury and Osteoarthritis Outcome Score (KOOS)—were assessed. Results: Sixty‐four patients were enroled. Medial ATT, lateral ATT and TT‐TG distance were significantly different pre‐operatively compared to post‐operative values, with the tibia translating anteriorly and rotating internally relative to the femur. ΔMedial ATT, ΔLateral ATT and ΔTT‐TG distance were 1.6, 8.8 and −4.8 mm, respectively. A negative correlation was observed between the ΔTT‐TG distance and the time elapsed since the injury (r = −0.44, p < 0.01). No correlation was found between ΔMedial ATT and the time elapsed since the injury, nor between ΔLateral ATT and the time elapsed since the injury. Neither the ΔMedial ATT, ΔLateral ATT, nor ΔTT‐TG distance correlated with the pre‐operative or post‐operative KOOS subscale scores. Conclusions: The tibia underwent internal rotation relative to the femur over time following ACL injury, highlighting the importance of assessing rotational changes in ACL‐injured knees. Level of Evidence: Level Ⅲ. [ABSTRACT FROM AUTHOR]

Purpose: One-stage revision anterior cruciate ligament reconstruction (ACLR) with the anatomic rectangular tunnel (RT) technique using bone–patellar tendon–bone (BTB) grafts results in anatomically precise tunnel placement and secure graft fixation. This study evaluated knee joint laxity and clinical outcomes in terms of femoral tunnel overlap. It was hypothesised that there would be no significant differences in knee joint laxity or clinical outcomes regardless of femoral tunnel overlap. Methods: Between 2012 and 2021, a single surgeon conducted 196 one-stage revision ACLRs with the RT technique using BTB grafts. Patients were divided based on the presence of femoral tunnel overlap. Knee joint laxity was evaluated using the Lachman test, pivot shift test, and side-to-side difference measured with a KT-1000 arthrometer. Clinical outcomes were assessed using the Lysholm score, Knee Injury and Osteoarthritis Outcome Score (KOOS), and International Knee Documentation Committee (IKDC) Knee Examination Form 2000. Knee joint laxity and clinical outcomes were compared between groups after a median follow-up of 2.5 years (range 2.0–8.0). Results: The study included 30 and 73 patients in the overlap and non-overlap groups, respectively. No significant differences were observed in the results of the Lachman test, pivot shift test, or KT-1000 arthrometer as well as in the Lysholm, KOOS, or IKDC scores between the two groups. Based on the IKDC scores, all patients were graded as normal or nearly normal. Conclusion: One-stage revision ACLR with the RT technique using BTB grafts improved knee joint laxity and had favourable clinical outcomes regardless of femoral tunnel overlap. To achieve optimal results in one-stage revision ACLR, it is crucial to create a tunnel within the anatomical attachment area and ensure proper graft fixation and tensioning. Level of evidence: III. [ABSTRACT FROM AUTHOR]

Background: Many countries are faced with aging populations. However, few studies have directly compared the clinical outcomes of medial opening-wedge high tibial osteotomy (OWHTO) and mobile-bearing unicompartmental knee arthroplasty (MB-UKA) in early elderly patients. Thus, we aimed to investigate the clinical outcomes after OWHTO and MB-UKA in early elderly patients with similar demographics and osteoarthritis (OA) severity. Methods: Three hundred and fifteen OWHTO and 142 MB-UKA were performed for medial compartment OA by a single surgeon between August 2009 and April 2020. Among them, patients aged 65–74 years with more than two years of follow-up were enrolled. The patient-reported outcome measures (PROMs), including visual analog scale (VAS) score and Japanese Knee Osteoarthritis Measure (JKOM) score, were compared between both procedures preoperatively and at the last follow-up. The PROMs were compared between the groups by Kellgren–Lawrence (K–L) OA grades. Results: Seventy-three OWHTO and 37 MB-UKA patients were enrolled. No significant differences were found in the distribution of age, gender, follow-up period, body mass index, and Tegner activity scale between the two procedures. The postoperative PROMs in patients with K–L grade 4 were better after MB-UKA than OWHTO at the mean follow-up of 5 years. No significant difference was found in PROMs in patients with K–L grades 2 and 3. Conclusion: ThePROMs after MB-UKA were superior to that after OWHTO in early elderly patients with severe OA. In particular, pain relief was better after MB-UKA than OWHTO with severe OA. Meanwhile, no significant difference in PROMs was found with moderate OA patients. Level of evidence: Level IVprospective cohort study. [ABSTRACT FROM AUTHOR]