Deleterious effect of LiCl on honeybee (Aphis mellifera) grubs and no effect on Varroa mites (Varroa destructor) under normal beekeeping management

A 2-year field experiment was performed to test lithium chloride, LiCl, application in a normal beekeeping management system. The effect of LiCl on bee larval mortality, beehive weight (honey production) and Varroa mite mortality were tested. Spectrometric quantification of Li on honey and the larval body were made to test the effectiveness of the presence of LiCl. Li was detected in bee larval bodies and in honey over 2 years, from 2018 to 2019. According to the results, no effect of LiCl on mite mortality or bee larval mortality was detected in the first year of application. By assessing the weight variation of beehives, only one LiCl-treated hive showed a significantly higher weight, whereas no other differences were detected between treatments and control. The same trend seen in 2018 was repeated in 2019, while a total bee larval mortality was observed after the first LiCl application, and still no differences in Varroa mite mortality were observed. According to these results, it was concluded that LiCl has no effect on Varroa mite mortality during normal beekeeping practice; furthermore, the recommended amount of treatment (25 mM) had a lethal effect (i.e., total mortality) on larvae following repeated applications.

Variation of Small and Large Wild Bee Communities Under Honeybee Pressure in Highly Diverse Natural Habitats

During the study, the honeybee effects on wild bees were tested and hypothesized that smaller distances from beehives will increase competitions between honeybees and wild bees, while greater distances will have a deleterious effect on competition. The impact on species richness and diversity was tested with distances from beehives, considering that this may differ when large and small wild bee species are considered separately. Altogether 158 species and 13,164 individuals were collected, from which 72% (9,542 individuals) were Apis mellifera. High variation in abundances was detected from one year to another, and the species turnover by sites was 67% in site A, 66% in site V, and 63% in site F. This last one was the site with the previous contact with honeybees. Considering distances from beehives, significant decreases in small bee species diversity were detected from one year to another at each distance except site F, 250 m from hives. The changes in species diversity and community structure of small bee species are detected from one year to another.

Preliminary assessment of cavity-nesting Hymenopterans in a low-intensity agricultural landscape in Transylvania

In this study, our aim was to assess several traits of cavity-nesting Hymenopteran taxa in a low-intensity agricultural landscape in Transylvania. The study took place between May and August 2018 at eight study sites in the hilly mountainous central part of Romania, where the majority of the landscape is used for extensive farming or forestry. During the processing of the trap nest material, we recorded several traits regarding the nests of different cavity-nesting Hymenopteran taxa and the spider prey found inside the nests of the spider-hunting representatives of these taxa. We also evaluated the relationship between the edge density and proportion of low-intensity agricultural areas surrounding the study sites and some of these traits. The majority of nests were built by the solitary wasp genus Trypoxylon, followed by the solitary wasp taxa Dipogon and Eumeninae. Solitary bees were much less common, with Hylaeus being the most abundant genus. In the nests of Trypoxylon, we mostly found spider prey from the family of Araneidae, followed by specimens from the families of Linyphiidae and Theridiidae. In the nests of Dipogon, we predominantly encountered spider prey from the family of Thomisidae. We found significant effects of low-intensity agricultural areas for the genera of Auplopus, Megachile, Osmia, and the Thomisid prey of Dipogon. We also found that the spider prey of Trypoxylon was significantly more diverse at study sites with higher proportions of low-intensity agricultural areas. Our results indicate that solitary bees seem to be more abundant in areas, where the influence of human activities is stronger, while solitary wasps seem to rather avoid these areas. Therefore, we suggest that future studies not only should put more effort into sampling in low-intensity agricultural landscapes but also focus more on solitary wasp taxa, when sampling such an area.

Comparison of wild bee communities of three semi-natural meadow habitats at Harghita–Covasna Region, Transylvania, Romania

In the temperate climate wild bees are the most important pollinator organisms. Pollination is essential for the communities of semi-natural habitats since this ecosystem service directly affects plant reproduction. The diversity of wild bees living in such areas is remarkably high, but they are susceptible to various anthropogenic influences.In our study, the composition and structure of wild bee communities were examined in Romania (Transylvania) at three semi-natural areas near Filia, Merești and Vârghiș. The surveyed areas were used as extensive meadows under relatively low but slightly different anthropogenic influence levels. We collected bees in these areas at several places (9 sampling points/area) by individual netting four times during the season. In the studied areas, 129 bee species were found, which makes up about 18% of the approximately 726 wild bee species registered in Romania. In addition to the high number of species, we also observed high diversity values. Our results showed that, even at our sampling site closest to the human settlements, the extensive use of the surveyed areas as meadows allows the development of diverse, species-rich bee communities.

Synthesis and biological effects of some kynurenic acid analogs

The overactivation of excitatory amino acid receptors plays a key role in the pathomechanism of several neurodegenerative disorders and in ischemic and post-ischemic events. Kynurenic acid (KYNA) is an endogenous product of the tryptophan metabolism and, as a broad-spectrum antagonist of excitatory amino acid receptors, may serve as a protective agent in neurological disorders. The use of KYNA is excluded, however, because it hardly crosses the blood-brain barrier. Accordingly, new KYNA analogs which can readily cross this barrier and exert their complex anti-excitatory activity are generally needed. During the past 6 years, we have developed several KYNA derivatives, among others KYNA amides. These new analogs included one, N-(2-N,N-dimethylaminoethyl)-4-oxo-1H-quinoline-2-carboxamide hydrochloride (KYNA-1), that has proved to be neuroprotective in several models. This paper reports on the synthesis of 10 new KYNA amides (KYNA-1-KYNA-10) and on the effectiveness of these molecules as inhibitors of excitatory synaptic transmission in the CA1 region of the hippocampus. The molecular structure and functional effects of KYNA-1 are compared with those of other KYNA amides. Behavioral studies with these KYNA amides demonstrated that they do not exert significant nonspecific general side-effects. KYNA-1 may therefore be considered a promising candidate for clinical studies.

Connections between personality and the symptomatology of alcohol use disorder

Introduction

Temperament and character factors and specific impulse control-related personality traits are connected to the developmental and clinical aspects of alcohol use disorder (AUD).

Objectives/aims

To reveal the underlying personality structure of individual differences in the symptom severity of AUD. Therefore temperament and character, impulsivity and aggression were assessed in relation to alcohol addiction severity.

Methods

Sixty-three patients with AUD were involved. Temperament and Character Inventory-Revised was used to quantify temperament and character dimensions. Impulsivity was assessed by the Barratt Impulsivity Scale-11 (BIS) and aggression by the Buss-Perry Aggression Questionnaire (BPAQ). To determine symptom severity of AUD the Severity of Alcohol Dependence Questionnaire (SADQ), the Alcohol Use Disorders Identification Test (AUDIT), the MacAndrew Alcoholism Scale-Revised (MAC-R) and the number of DSM-IV alcohol dependence symptoms were registered. To analyze the connections between symptom severity indicators and personality factors Pearson and Spearman correlation analysis were applied, p < 0.05 were considered significant.

Results

SADQ (r = 0.290), AUDIT (r = 0.345), MAC-R (r = 0.504) and the DSM-IV alcohol dependence symptoms (Spearman rho = 0.271) correlated positively with novelty-seeking temperament factor. SADQ (r = 0.262) and AUDIT (r = 0.293) scores correlated positively with BIS. Furthermore SADQ (r = 0.382), AUDIT (r = 0.318), MAC-R (r = 0.416) correlated positively with BPAQ.

Conclusions

Novelty-seeking, impulsivity and aggression as indicators of impulse control have different theoretical backgrounds but a common root. This study has revealed that the adverse consequences of lower impulse control can lead to more severe symptoms of AUD. These connections between impulse control and the symptomatology could contribute to a better understanding of the clinical complexity of AUD.

Vectorial bicarbonate transport by Par-C10 salivary cells

Salivary glands produce a HCO(3)(-)-rich fluid that is important for the neutral milieu in the upper gastrointestinal tract. The molecular mechanism of this secretion is poorly understood. Par-C10, an immortalized rat parotid acinar line, has been shown to secrete Cl(-)- in response to Ca(2+-)-mobilizing stimuli. Our aim was to assess the capacity of polarized monolayers of Par-C10 cells to transport and secrete HCO(3)(-)-. Transepithelial electrolyte movement was evaluated by short-circuit current measurements. Intracellular pH (pH(i)) was measured by microfluorometry in cells loaded with BCECF. Monolayers of Par-C10 cells, grown on Transwell membranes, developed high transepithelial resistance and exhibited vectorial anion secretion which was activated by both ATP and forskolin. The currents were partially inhibited by bumetanide and by withdrawal of HCO(3)(-) indicating the dependence of ion movements on NKCC and on HCO(3)(-) ions, respectively. In HCO(3)(-)-free solutions the recovery of pH(i) from acid loading was abolished by EIPA. In the presence of HCO(3)(-) there was a strong EIPA-insensitive recovery from acid loading which was inhibited by H(2)DIDS. ATP and forskolin stimulated HCO(3)(-) efflux from the cells. Furthermore, HCl(-) withdrawal experiments showed the presence of DNDS-sensitive basolateral anion exchange. In conclusion Par-C10 cells achieve transepithelial transport that is sensitive to both intracellular Ca(2+)- and cAMP-dependent stimulation. We identified Na(+)/H(+) exchange, Na(+)-HCO(3)(-) cotransport and anion exchange at the basolateral side of the cells as being involved in intracellular pH regulation and vectorial HCO(3)(-) secretion. This cell line offers a good model for further studies to understand the molecular mechanisms of salivary HCO(3)(-) secretion.

[Prion dementias: nosology and diagnostic difficulties in the spectrum of Creutzfeld-Jakob encephalopathy]

Creutzfeldt-Jakob disease (CJD) is one form of subacute prion diseases with spongiform encephalopathy. Hereditary, infectious and sporadic types of the disorder can be distinguished. The abnormal transformation of the prion protein, relevant in the normal synaptic transmission is considered as an important factor in the development of this disease. Gerstmann-Sträussler-Scheinker syndrome (GSS) and familial fatal insomnia (FFI) are the other diseases belonging to the same disease spectrum. The common feature of these disorders is that the different mutation of the same prion protein could result in different phenotypes and symptoms. CJD is considered as a neurologic disorder but the clinical symptoms and differential diagnosis of the disease are also relevant problems in psychiatry. Because of the early onset of dementia and the psychotic and delusive symptoms, the patients with CJD are frequently admitted to psychiatric wards. Recently worldwide public interest has been focused on prion dementias because of the possible human transmission of bovine spongiform encephalopathy in the UK. The diagnostic problems of our seven CJD patients diagnosed since 1991 in the catchment area of Szeged city are discussed in the view of recent findings of molecular biology, nosology, diagnostic and therapeutic problems of this devastating disease.

Location and quantification of metal ions in enzymes combining polyacrylamide gel electrophoresis and particle-induced X-ray emission

A method is presented to identify and determine the relative amounts of protein-bound metal ions in situ. Proteins or their subunits are separated by SDS-PAGE, the appropriately dried gel sections are directly scanned by a collimated proton beam of 3 MeV energy, and the characteristic X-rays produced are detected. The determination of Fe content of an iron-sulfur protein (HiPiP), as well as the Fe and Ni analysis of the hydrogenase from Thiocapsa reseopersicina, have shown the feasibility of this technique.

Metal composition analysis of hydrogenase from Thiocapsa roseopersicina by proton induced X-ray emission spectroscopy

Polyacrylamide gel electrophoresis combined with proton induced X-ray emission spectroscopy is suitable to identify and to determine the relative amounts of protein bound metals in situ. An analysis of the hydrogenase from Thiocapsa roseopersicina has shown the feasibility of the technique and provides new insight into the relative amount as well as the intramolecular location of Fe and Ni metal atoms in this enzyme.

Elemental analysis of samples of biological origin relative to their protein content by means of charged particle bombardment

The particle-induced X-ray emission (PIXE) method and the 14N(d,p)15N nuclear reaction are combined for simultaneous trace element and nitrogen determination. Measurement of nitrogen content often allows the relating of the elemental concentrations determined by PIXE to the protein content of the sample. For the measurements only a small amount of sample material is needed; therefore, it is possible to keep track of the quantity of a certain element in the successive steps of a biomedical separation process. In about 10 min, trace element concentrations in the ppm range can be determined with a statistical accuracy of about 10%.