Comparing response of buff-tailed bumblebees and red mason bees to application of a thiacloprid-prochloraz mixture under semi-field conditions.

Recent studies have reported interspecific differences in how bee species respond to various stressors. Evaluating the exposure and responses of different bee species to plant protection products is considered an essential part of their risk assessment. This study was conducted to assess the impacts of thiacloprid-prochloraz mixture on buff-tailed bumblebees (Bombus terrestris) and red mason bees (Osmia bicornis) in a worst-case scenario under semi-field conditions. Bumblebee colonies or solitary bee trap nests were confined in tunnels with flowering oilseed rape. The recommended maximum application rates of 72 g thiacloprid/ha and 675 g prochloraz/ha were applied as a tank mixture during bee flight in full flowering oilseed rape. Several parameters such as flight and foraging activity, population parameters, and exposure level were investigated. Our results show adverse effects of the combination of thiacloprid and prochloraz on the reproductive performance of red mason bees. The number of cocoons produced by O. bicornis was significantly reduced in the treatment compared to the control group. Regarding bumblebees, we found no effects of the thiacloprid-prochloraz mixture on any observed parameters of colony development. The maximum detected concentrations of both active substances three days after application were higher in O. bicornis pollen mass compared to B. terrestris stored pollen. We conclude that this worst-case scenario of thiacloprid-prochloraz exposure poses a high risk to solitary bees and thus the use of such mixture should be restricted.

Large-scale study investigating the effects of a tank mixture containing thiacloprid-prochloraz on honey bees (Apis mellifera).

Risk assessment of plant protection products (PPPs) will be conducted before authorization for their possible effects on non-target organisms, including honey bees. Tank mixtures are often common practice by farmers, and mostly their effects on honey bees are not routinely assessed. To enable a realistic assessment of laboratory-reported effects of a combination of the insecticide thiacloprid and fungicide prochloraz on honey bees, a large-scale field study with spray application in winter oilseed rape was conducted in four regions in Germany. Several parameters were investigated, including mortality, flight activity, and colony development. Residue analysis of various materials (e.g., dead bees, nectar, and pollen) was conducted to assess exposure level. We observed several intoxication symptoms 2 h after application, including a high number of moribund bees and dead bees on the first day after application (DAA +1) compared to the control. Adverse effects were observed on the number of open brood cells, with a significant reduction of approximately 22% compared to control over the experimental period. High residue concentrations were detected on flowers and dead bees on the day of application, which decreased rapidly within six days. The residue concentrations detected were higher in bee-collected materials than in materials stored in the hive. In conclusion, exposure to a combination containing thiacloprid-prochloraz poses a high risk to honey bees. Thus, the application of such a mixture on flowering crops is restricted in Germany.

Urinary miRNA profiles discriminate between obstruction-induced bladder dysfunction and healthy controls.

Urgency, frequency and incomplete emptying are the troublesome symptoms often shared between benign prostatic obstruction-induced (BLUTD) and neurogenic (NLUTD) lower urinary tract dysfunction. Previously, using bladder biopsies, we suggested a panel of miRNA biomarkers for different functional phenotypes of the bladder. Urine is a good source of circulating miRNAs, but sex- and age-matched controls are important for urinary metabolite comparison. In two groups of healthy subjects (average age 32 and 57 years old, respectively) the total protein and RNA content was very similar between age groups, but the number of secreted extracellular vesicles (uEVs) and expression of several miRNAs were higher in the young healthy male volunteers. Timing of urine collection was not important for these parameters. We also evaluated the suitability of urinary miRNAs for non-invasive diagnosis of bladder outlet obstruction (BOO). A three urinary miRNA signature (miR-10a-5p, miR-301b-3p and miR-363-3p) could discriminate between controls and patients with LUTD (BLUTD and NLUTD). This panel of representative miRNAs can be further explored to develop a non-invasive diagnostic test for BOO. The age-related discrepancy in the urinary miRNA content observed in this study points to the importance of selecting appropriate, age-matched controls.