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Review: Nutritional Needs of Honeybees and Legislation on Apiculture By-Products in Animal Nutrition
No full textHoneybees are some of the smallest farmed animals, and apiculture by-products, e.g., honey, beeswax, propolis, royal jelly, and pollen contribute to animal nutrition. For the effective production of these by-products, the optimal development and nutrient supply of the honeybee is required. Beginning with the development of the mouth and anal pores on the second day of embryonic development, the digestive tract differentiates into the mouth and fore-, mid-, and hindgut during the pupal stage. The various glands within the oral cavity are particularly important, secreting enzymes and substances that are crucial for digestion and hive nutrition, e.g., invertase and royal jelly. Honeybees rely on a specialized caste system, with worker bees collecting nectar, pollen, water, and resin for the nutrition of the entire hive. Macronutrients, including proteins, carbohydrates, and lipids, obtained primarily from pollen and nectar, are essential for the growth and development of larvae and the overall health of the colony. Inadequate nutrient intake can lead to detrimental effects on larval development, prompting cannibalism within the hive. Apiculture by-products possess unique nutritional and therapeutic properties, leading to a growing interest in the use of honey, beeswax, propolis, and pollen as a feed additive. In recent years, the use of apicultural by-products in animal nutrition has been primarily limited to in vivo studies, which have demonstrated various positive impacts on the performance of farm animals. Honey, beeswax, propolis, royal jelly, and pollen are listed feed stuffs according to Regulation (EC) No. 68/2013. However, for animal nutrition there is not any specific legal definition for these products and no legal requirements regarding their ingredients as given for honey or beeswax in European food law
Direct evidence for ligand-enhanced activity of Cu(i) sites
No full textLittle is known about the strong mediating effect of the ligand sphere and the coordination geometry on the strength and isotopologue selectivity of hydrogen adsorption on the undercoordinated copper(I) site. Here, we explore this effect using gas-phase complexes Cu+(H2O)(H2)n (with n ≤ 3) as model systems. Cu+(H2O) attracts dihydrogen (82 kJ mol−1) more strongly than bare Cu+ (64 kJ mol−1) does. Combining experimental and computational methods, we demonstrate a high isotopologue selectivity in dihydrogen binding to Cu+(H2O), which results from a large difference in the adsorption zero-point energies (2.8 kJ mol−1 between D2 and H2, including an anharmonic contribution of 0.4 kJ mol−1). We investigate its origins and the bond strengthening between Cu+ and H2 upon addition of a single H2O ligand. We discuss the role of the environment and the coordination geometry of the adsorption site in achieving a high selectivity and the ramifications for identifying and designing future materials for adsorptive dihydrogen isotopologue separation
Post-Synthetically Treated ERI and SSZ-13 Zeolites Modified with Copper as Catalysts for NH3-SCR-DeNOx
No full textERI and SSZ-13 were subjected to post-synthetic treatments (depending on the zeolite topol-
ogy) to create micro-/mesoporous materials. The results in terms of NH3-SCR-DeNOx show that the
applied treatments improved the catalytic activity of the Cu-containing ERI-based materials; however,
the NO conversion did not vary for the different materials treated with NaOH or NaOH/HNO3.
For the micro-/mesoporous Cu-containing SSZ-13, a lower NO conversion in NH3-SCR-DeNOx
was observed. Thus, our findings challenge the current paradigm of enhanced activity of micro-
/mesoporous catalysts in NH3-SCR-DeNOx. The modification of the supports results in the presence
of different amounts and kinds of copper species (especially isolated Cu2+ and aggregated Cu species)
in the case of ERI- and SSZ-13-based samples. The present copper species further differentiate the
formation of reactive reaction intermediates. Our studies show that besides the μ-η2,η2-peroxo
dicopper(II) complexes (verified by in situ DR UV-Vis spectroscopy), copper nitrates (evidenced by
in situ FT-IR spectroscopy) also act as reactive intermediates in these catalytic systems
Enhanced Performance of the Optimized Dye CF583R in Direct Stochastic Optical Reconstruction Microscopy of Active Zones in Drosophila Melanogaster
No full textSuper-resolution single-molecule localization microscopy (SMLM) of presynaptic active zones (AZs) and postsynaptic densities contributed to the observation of protein nanoclusters that are involved in defining functional characteristics and in plasticity of synaptic connections. Among SMLM techniques, direct stochastic optical reconstruction microscopy (dSTORM) depends on organic fluorophores that exert high brightness and reliable photoswitching. While multicolor imaging is highly desirable, the requirements necessary for high-quality dSTORM make it challenging to identify combinations of equally performing, spectrally separated dyes. Red-excited carbocyanine dyes, e.g., Alexa Fluor 647 (AF647) or Cy5, are currently regarded as “gold standard” fluorophores for dSTORM imaging. However, a recent study introduced a set of chemically modified rhodamine dyes, including CF583R, that promise to display similar performance in dSTORM. In this study, we defined CF583R’s performance compared to AF647 and CF568 based on a nanoscopic analysis of Bruchpilot (Brp), a nanotopologically well-characterized scaffold protein at Drosophila melanogaster AZs. We demonstrate equal suitability of AF647, CF568 and CF583R for basal AZ morphometry, while in Brp subcluster analysis CF583R outperforms CF568 and is on par with AF647. Thus, the AF647/CF583R combination will be useful in future dSTORM-based analyses of AZs and other subcellularly located marker molecules and their role in physiological and pathophysiological contexts
Vascular Closure Devices For Axillary Artery Access: A Systematic Review and Meta-Analysis
No full textPurpose: To evaluate the technical success and complication rates of vascular closure devices (VCDs) in the axillary
artery. Materials and Methods: MEDLINE and Embase were searched independently by two reviewers to identify
observational studies from inception through October 2021. The following outcomes were meta-analyzed: technical success,
hematoma, dissection, pseudoaneurysm, infection, and local neurological complications. Complications were also graded
as mild, moderate, and severe. A logistic regression evaluating the influence of sheath size for the outcome of technical
success rate was performed using individual patient–level data. Results: Of 1496 unique records, 20 observational studies
were included, totaling 915 unique arterial access sites. Pooled estimates were as follows: technical success 84.8% (95%
confidence interval [CI]: 78%–89.7%, I 2=60.4%), hematoma 7.9% (95% CI: 5.8%–10.6%, I 2=0%), dissection 3.1% (95% CI:
1.3%–7.3%, I2=0%), pseudoaneurysm 2.7% (95% CI: 1.3%–5.7%, I2=0%), infection <1% (95% CI: 0%–5.7%, I2=20.5%), and
local neurological complications 2.7% (95% CI: 1.7%–4.4%, I2=0%). There was a significant negative association between
sheath size and technical success rate (odds ratio [OR]: 0.87 per 1 French (Fr) increase in sheath size, 95% CI: 0.80–0.94,
p=0.0005). Larger sheath sizes were associated with a greater number of access-site complications (adjusted odds ratio
[aOR]: 1.21 per 1 Fr increase sheath size, 95% CI: 1.04–1.40, p=0.013). Conclusions: Off-label use of VCDs in the axillary
artery provides an 85% successful closure rate and variable complication rate, depending on the primary procedure and
sheath size. Larger sheaths were associated with a lower technical success and greater rate of access-related complications
Neglected Tropical Diseases: A Chemoinformatics Approach for the Use of Biodiversity in Anti-Trypanosomatid Drug Discovery
No full textRapid Climate Change, Integrated Human-Environment-Historical Records and Societal Resilience in Georgia
No full textIn the midlatitudes of the planet, we are facing the imminent disappearance of one of our best high-resolution (pre)historic climate and anthropogenic pollution archives, namely the loss of glacial ice, through accelerated global warming. To capture these records and interpret these vanishing archives, it is imperative that we extract ice-cores from midlatitude regions where glaciers still survive and analyse them within frameworks of inter-disciplinary research. In this paper, we focus on Georgia, part of the Greater Caucasus. Results of ice-core analyses from the region have never, to date, been integrated with its other abundant palaeo-environmental, archaeological and historical sources. We review the results of international projects on palaeo-environmental/geoarchaeological sediment archives, the archaeology of metal economies and preliminary ice-core data in Georgia. Collectively, we show that the different strands need to be integrated to fully explore relationships between climate/landscape change and human societal transformations. We then introduce an inclusive interdisciplinary framework for ongoing research on these themes, with an ultimate future goal of using data from the past to inform societal resilience strategies in the present
Temperature-Dependent tRNA Modifications in Bacillales
No full textTransfer RNA (tRNA) modifications are essential for the temperature adaptation of thermophilic and psychrophilic organisms as they control the rigidity and flexibility of transcripts. To further understand how specific tRNA modifications are adjusted to maintain functionality in response to temperature fluctuations, we investigated whether tRNA modifications represent an adaptation of bacteria to different growth temperatures (minimal, optimal, and maximal), focusing on closely related psychrophilic (P. halocryophilus and E. sibiricum), mesophilic (B. subtilis), and thermophilic (G. stearothermophilus) Bacillales. Utilizing an RNA sequencing approach combined with chemical pre-treatment of tRNA samples, we systematically profiled dihydrouridine (D), 4-thiouridine (s4U), 7-methyl-guanosine (m7G), and pseudouridine (Ψ) modifications at single-nucleotide resolution. Despite their close relationship, each bacterium exhibited a unique tRNA modification profile. Our findings revealed increased tRNA modifications in the thermophilic bacterium at its optimal growth temperature, particularly showing elevated levels of s4U8 and Ψ55 modifications compared to non-thermophilic bacteria, indicating a temperature-dependent regulation that may contribute to thermotolerance. Furthermore, we observed higher levels of D modifications in psychrophilic and mesophilic bacteria, indicating an adaptive strategy for cold environments by enhancing local flexibility in tRNAs. Our method demonstrated high effectiveness in identifying tRNA modifications compared to an established tool, highlighting its potential for precise tRNA profiling studies
Respiratory Symptoms and Changes of Oxidative Stress Markers among Motorbike Drivers Chronically Exposed to Fine and Ultrafine Air Particles: A Case Study of Douala and Dschang, Cameroon
No full textRecent studies revealed that the high production of reactive oxidative species due to exposure to fine or ultrafine particles are involved in many chronic respiratory disorders. However, the poor standard of clinical data in sub-Saharan countries makes the assessment of our knowledge on the health impacts of air pollution in urban cities very difficult. Objective: The aim of this study was to evaluate the distribution of respiratory disorders associated with exposure to fine and ultrafine air particles through the changes of some oxidative stress biomarkers among motorbike drivers from two cities of Cameroon. Methods: A cross-sectional survey using a standardized questionnaire was conducted in 2019 on 191 motorcycle drivers (MDs) working in Douala and Dschang. Then, the activities of superoxide dismutase (SOD) and the level of malondialdehyde (MDA) were measured using colorimetric methods. The data of participants, after being clustered in Microsoft Excel, were analyzed and statistically compared using SPSS 20 software. Results: The motorbike drivers recruited from both cities were from 21 to 40 years old, with a mean age of 29.93 (±0.82). The distribution of respiratory disorders, such as a runny nose, cold, dry cough, chest discomfort, and breathlessness, was significantly increased among MDs in Douala. According to the results of biological assays, SOD and MDA were significantly greater among the MDs recruited in Douala compared to those of Dschang. The change in these oxidative stress markers was significantly positively correlated with the mobilization of monocytes and negatively correlated with neutrophils, showing the onset and progression of subjacent inflammatory reactions, and it seemed to be significantly influenced by the location MDs lived in. Conclusions: Through this study, we have confirmed the evidence supporting that the onset and progression of oxidative stress is caused by the long-term exposure to fine or ultrafine air particles among working people living in urban cities. Further studies should be conducted to provide evidence for the cellular damage and dysfunction related to the chronic exposure to fine particulate matter (PM) in the air among working people in the metropolitan sub-Saharan Africa context