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Honey bee workers (Apis mellifera L.) collect nectar, honeydew and pollen from plants in orderto provide the colony with, among others, carbohydrates and protein. Whenever these sources are unavailable in the environment, bees turn to alternatives. An example of this are fungi spores collected accidentally or on purpose. This last phenomenon is the aim of this study, in which we have shown that worker bees can collect willow rust (Melampsora spp.) spores. We observed as the bees obtained spores and placed them in pollen baskets. The presence of spores was demonstrated with the use of a scanning electron microscope (SEM). This observation indicates that the honey bee may use alternative sources as a potential supplement. There are few studies in this field and it requires a deeper analysis.

The honey bee has a significant environmental and economic impact. While collecting food or water, bees are exposed to negative physical and chemical factors that lead to physiological and behavioral changes and, consequently, even death. Along with the development of technology and communication, electromagnetic fields produced by artificial emitters have begun to have an impact on the environment. The aim of the study was to check whether the electromagnetic field also impacts antioxidant enzymes functioning in the honey bee's organism. The study was conducted under laboratory conditions, and one-day and seven-day-old honey bee workers were used in the experiment. Honey bee workers were exposed to an electromagnetic field with a frequency of 50Hz and variable intensity in the range of 1–10 kV/m. Immediately after the end of the exposure, hemolymph was collected from the bees for biochemical analysis. The results of the research did not show clearly whether changes in the activity of biochemical markers were affected by the time spent in the electromagnetic field or its intensity but did show that there was a difference in physiology between one-day-old and seven-day-old bees.

Introduction: Helicobacter pylori causes chronic gastric diseases in nearly 50% of people around the world. It is suggested that biofilm formation has a pronounced effect on the dynamic resistance spread and recurrence of these infections. Methods: To mimic the scenario of therapeutic ineffectiveness, we investigated the impact of sub-minimal inhibitory concentrations (sub-MICs) of antibiotics on the development and parameters of biofilms produced by clinical H. pylori strains. Results: We observed that constant exposure of planktonic forms to metronidazole or levofloxacin stimulated the speed of autoaggregation and the amount of extracellular matrix, resulting in increased dimensions of the developed biofilms. Contrary to this, continuous exposure to clarithromycin negatively affected a number of biofilm-related reactions and led to the biofilm-weakening effect. Through assessing the membrane fatty acid profiles of antibiotic-exposed cells, we confirmed that metronidazole and levofloxacin induced a biofilm-like phenotype, while clarithromycin kept bacteria in a planktonic form. Discussion: Our results suggest that sub-MICs of antibiotics affect the biochemical and biophysical properties of the developing biofilm of H. pylori strains and may impact the effectiveness of antibiotic treatment. [ABSTRACT FROM AUTHOR]

Simple Summary: In agriculture, plant protection products are used to improve crop yields. They pose a threat to organisms that are not the target of their control. For this purpose, biopesticides have been used, which are supposed to show less toxicity to the environment and non-targeted organisms. On the other hand, natural pesticides can also show toxicity to insects. The honey bee is one of the insects that is still exposed to contact with residues of plant protection products, which poses a threat to this organism. Honey bees use pollen and nectar from flowers to produce food. Because they often forage on crops, they are at risk of being exposed to plant protection products (PPPs), both directly and in stored food. Due to the adverse effects of synthetic PPPs on pollinators, biopesticides may be a viable alternative. Common tansy extract is used as one of the natural substitutes for synthetic pesticides. In our study, the effect of fermented common tansy extract on aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), and gamma-glutamyl transpeptidase (GGTP) activity and the concentration of triglycerides (TGs), total protein (TP), total antioxidant status (TAS), and glucose in honey bee workers' hemolymph was assessed. These biochemical markers give valuable information about the immunity, detoxification, and nutrition of a bee's body. Caged bees were given tansy extract added at various concentrations in sugar syrup for 24 h. Then, they were provided with only sugar syrup. After 7 days of the experiment, hemolymph was collected and analyzed. We observed changes in the activity of AST, ALT, GGTP enzymes and TG, TP, and glucose levels, but not all changes were statistically significant. In terms of AST activity, statistically significant differences were found. All groups tested, including the negative control group, showed reduced enzyme activity values compared to the positive control group. In TG concentration, differences were observed between the groups receiving 2% extract and 1% ethanol. Glucose levels differed between the groups receiving 1% extract and 2% extract and between the positive control group and 1% extract. Bee body proper functioning is affected by changes in enzyme activity, especially those responsible for immunity and detoxification, such as AST, ALT, ALP, and GGTP. Despite the short time of bees' exposure to the agent, the results of study show visible effects. Our results provide a basis for further research on the impact of tansy extract on honey bees. [ABSTRACT FROM AUTHOR]

Helicobacter pylori is one of the most common bacterial pathogens worldwide and the main etiological agent of numerous gastric diseases. The frequency of multidrug resistance of H. pylori is growing and the leading factor related to this phenomenon is its ability to form biofilm. Therefore, the establishment of a proper model to study this structure is of critical need. In response to this, the aim of this original article is to validate conditions of the optimal biofilm development of H. pylori in monoculture and co-culture with a gastric cell line in media simulating human fluids. Using a set of culture-based and microscopic techniques, we proved that simulated transcellular fluid and simulated gastric fluid, when applied in appropriate concentrations, stimulate autoaggregation and biofilm formation of H. pylori. Additionally, using a co-culture system on semi-permeable membranes in media imitating the stomach environment, we were able to obtain a monolayer of a gastric cell line with H. pylori biofilm on its surface. We believe that the current model for H. pylori biofilm formation in monoculture and co-culture with gastric cells in media containing host-mimicking fluids will constitute a platform for the intensification of research on H. pylori biofilms in in vitro conditions that simulate the human body. [ABSTRACT FROM AUTHOR]

Bee organisms need nutrients to function properly. Deficiencies of any nutrients decrease the condition and shorten the lifespan of insects. Moreover, protein deficiency decreases honey bee queen productivity and increases aggression in bee colonies. All of these aspects affect the efficiency and the economic aspect of beekeeping production. Limited access to sustainable feed sources for bee colonies during the season forces beekeepers to search for new sources of nutrients, particularly protein. The aim of this study was to investigate the potential use of brewers' spent grain, which is a by-product of beer production, as a source of protein additive in bees' diet. Two types of brewers' spent grain were examined: that from light beer and that from dark porter beer. The spent grains, especially porter spent grains, improved the hemolymph protein content compared to bees fed with sugar cake without additives. It did not fully correspond to the protein levels obtained from bees fed cake with the addition of pollen, but it may be a substitute. The studies showed that brewers' spent grain has the potential to be used as an alternative plant protein component of honey bee feed. [ABSTRACT FROM AUTHOR]

Hemolymph is the “blood” circulating in the entire insect body. Analysis of this fluid gives information about the condition of the insect. The most precise analyses are conducted on insects’ hemolymph suspended in 0.6% physiological saline (NaCl). Most current hemolymph extraction methods are either difficult or do not provide pure material, the contamination of collected insect “blood” can change results. This study aimed to develop a technique for extract hemolymph, both easy and without risk of contaminating derived material. The presented method is a modification of available ways to extract, store and transport hemolymph with the use of a glass capillary. For the development of this technique, adult worker honey bees (Apis mellifera L.) were used. The method required such basic equipment as a glass capillary, sterile tweezer, Eppendorf tube and physiological saline. The collected hemolymph were frozen and hence sent in a glass capillary to another laboratory for analysis.

Urinary infections related to the presence of bacterial biofilm on catheters are responsible for loss of patients’ health and, due to their high frequency of occurrence, generate a significant economic burden for hospitals. Klebsiella pneumoniae is a pathogen frequently isolated from this type of infection. In this study, using a cohesive set of techniques performed under stationary and flow conditions, we assessed the ability of 120 K. pneumoniae strains to form biofilm on various surfaces, including catheters, and evaluated the usefulness of clinically applied and experimental compounds to remove biofilm. The results of our study indicate the high impact of intraspecies variability with respect to K. pneumoniae biofilm formation and its susceptibility to antimicrobials and revealed the crucial role of mechanical flushing out of the biofilm from the catheter’s surface with use of locally active antimicrobials. Therefore, our work, although of in vitro character, may be considered an important step in the direction of efficient reduction of K. pneumoniae biofilm-related hospital infections associated with the presence of urine catheters.

The honey bee obtains food from bee forage, which comprises crops grown in multi-hectare agricultural fields where various types of plant protection products such as pesticides are used. Some of these negatively affect the honey bee organism. In our research, we aimed to evaluate the effects of three pesticide groups: fungicides (tebuconazole), insecticides (acetamiprid), herbicides (glyphosate), and their mixtures on the functioning of honey bee workers (A. mellifera carnica). Pesticides in various proportions and dilutions were added to sugar syrups and then fed to the bees. Mortality and food intake were recorded daily, while hemolymph analysis was performed after seven days of exposure. Food intake, mortality, and the results of various biochemical analyses differed between the experimental group and the control group receiving untreated sugar syrup. PPP's mixture of glyphosate tebuconazole and acetamiprid is more toxic to bees than single pesticides. Certain protection products such as pesticides can disrupt the antioxidant and detoxification systems associated with immunity in honey bees. Consequently, honey bees experience weaker conditions and their proper functioning deteriorates. The results obtained from biochemical changes provide a basis for field studies. [ABSTRACT FROM AUTHOR]

Bee pollen and bee bread from stationary apiaries in the southwest Polish Legnica-Glogow copper district (LGOM) were analyzed for Cr, Pb, Cd and As by ICP-AES. Their concentrations in both products were As > Cr > Pb > Cd. Concentrations in bee pollen were higher than in bee bread. Average Cr, Pb, As and Cd concentrations in bee products were 0.138, 0.093, 0.325, and 0.019 mg kg−1, respectively. Chromium was the most problematic element in bee pollen because its concentration limit was exceeded in more than 50% of the samples. Differences in Cd level between bee pollen and bread were significant (p ≤ 0.05)

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This study aimed to determine the proximate composition, gross energy, and amino acid amounts and mineral content in red mason bee Osmia bicornis (syn. Osmia rufa) cocoons to define their possible uses. This is the first study documenting the proximate composition and amounts of amino acids in Osmia bicornis cocoons. Like all other insect cocoons, red mason bee cocoons consist of silk. Samples were analyzed using AOAC standard methods. The dominant component of the examined cocoons was crude protein, which accounted for 52.91%. The examined cocoons were found to contain a considerable amount of crude fiber (30.69%)(consisting of NDF – 54.03% and ADF – 45.97%). Red mason bee cocoons consisted of 18 amino acids, including 39% of essential amino acids (EAA). The examined cocoons contained a significant amount of minerals. It appears from comparing the obtained results with other sources of dietary fiber in products of insect origin, that the Osmia bicornis cocoon differs in its composition. However, this fact may indicate its unique properties. [ABSTRACT FROM AUTHOR]