Modulation of Higher-Order Olfaction Components on Executive Functions in Humans

The prefrontal (PFC) and orbitofrontal cortex (OFC) appear to be associated with both executive functions and olfaction. However, there is little data relating olfactory processing and executive functions in humans. The present study aimed at exploring the role of olfaction on executive functioning, making a distinction between primary and more cognitive aspects of olfaction. Three executive tasks of similar difficulty were used. One was used to assess hot executive functions (Iowa Gambling Task-IGT), and two as a measure of cold executive functioning (Stroop Colour and Word Test-SCWT and Wisconsin Card Sorting Test-WCST). Sixty two healthy participants were included: 31 with normosmia and 31 with hyposmia. Olfactory abilities were assessed using the ‘‘Sniffin’ Sticks’’ test and the olfactory threshold, odour discrimination and odour identification measures were obtained. All participants were female, aged between 18 and 60. Results showed that participants with hyposmia displayed worse performance in decision making (IGT; Cohen’s-d = 0.91) and cognitive flexibility (WCST; Cohen’s-d between 0.54 and 0.68) compared to those with normosmia. Multiple regression adjusted by the covariates participants’ age and education level showed a positive association between odour identification and the cognitive inhibition response (SCWT-interference; Beta = 0.29; p = .034). The odour discrimination capacity was not a predictor of the cognitive executive performance. Our results suggest that both hot and cold executive functions seem to be associated with higher-order olfactory functioning in humans. These results robustly support the hypothesis that olfaction and executive measures have a common neural substrate in PFC and OFC, and suggest that olfaction might be a reliable cognitive marker in psychiatric and neurologic disorders.     

Changes in the biological activity of agropyrene on combined application with humus substances in the cultivation ofScenedesmus obliquus (TURP.) krüger

The work is concerned with the question of the effect of humic acids on the biological action of agropyrene, the effective substance from the rootstock of Agropyron repens (L.) P. BEAUV. The test organism was the alga Scenedesmus obliquus (TURP.) KRÜGER, cultivated in mineral solution. The basic biological test was the determination of the number and size of the cells of this alga. It was found that the way in which agropyrene acts on combined application with humus acids depends on which humus fraction is used. It can display a synergic action if humic acid is used, since this substance probably facilitates the penetration of agropyrene into the cells. On the other hand, fulvic acid counteracts the activity of agropyrene and this most probably by mutual binding and blocking of active groups and links.     

An analysis of spontaneous behavior following acute MDMA treatment in male and female rats

3,4-methylenedioxymethamphetamine (MDMA, ecstasy) is a widely abused drug that impairs behavioral, emotional and cognitive functions in humans and animals. The aim of this study was to evaluate MDMA effects on the spontaneous behavioral repertoire of rats with a focus on the gender differences. MDMA was given subcutaneously in a single dose of 2.5, 5 and 10 mg/kg and the spontaneous behavior of male and female rats was studied using the open field test. Behavioral patterns (locomotion, rearing, floor-sniffing, air-sniffing, grooming, immobility and stereotypy) were registered in two sessions - 30 and 60 min following MDMA administration; each session lasting 5 min. We found that MDMA totally disrupted the structure and timing of spontaneous behavioral patterns in both genders; no evident differences were measured between either of the sessions. MDMA irrespective of the dosage produced hyperlocomotion, excessive floor-sniffing and almost absolute suppression of grooming and immobility. A biphasic effect of MDMA was found in rearing. Gender differences were present namely in rearing and sniffing stereotypy. This study also confirms that behavioral experiments should focus on more behavioral elements than only on e.g. locomotion and that the observer-based approach still gives the most reliable results.     

The capacity of crab megalopae to autotomize body appendages and the consequences upon their feeding ability–the price to pay to live another day

During the mass settlement events of brachyuran crabs, there is a significant chance of density-dependent injury in the megalopae (last larval stage) because cannibalism can occur by larger conspecifics. Laboratory observations revealed that the appendages that are more prone to injury are eyestalks, as well as first (P1) and fifth (P5) pereiopods. The ability of Carcinus maenas megalopae to autotomize these structures and the effect of such injuries in their feeding ability and metamorphosis were investigated. All tested specimens were able to autotomize one or both of their P1 and P5, but not their eyestalks. Megalopae missing a single P1, as well as one or both P5, were able to capture and ingest prey, as well as intact specimens. Megalopae with either P1 and P5 appendages or at least one damaged eyestalk failed to ingest sufficient food to reach the nutritional threshold required to successfully metamorphose.     

Activation of protein kinase C suppresses fragmentation of pig oocytes aged in vitro

When cultured for an extended time, pig oocytes that matured in vitro to the stage of metaphase II undergo the complex process designated as ageing. Under our conditions, some pig oocytes aged 3 days remained at the stage of metaphase II (22%), but others underwent spontaneous parthenogenetic activation (45%), and still others perished through fragmentation (28%) or lysis (5%). Activation of protein kinases C (PKCs) using phorbol-12-myristate-13-acetate (PMA) protects oocytes from fragmentation. None of the oocytes were fragmented after 3 days of aging in 50 nM of PMA. A similar effect (8% of fragmented oocytes) was observed after a 3-day treatment of aging oocytes with 100 μM of 1-stearoyl-2arachidonoyl-sn-glycerol (STEAR). PMA and STEAR activate both calcium-dependent and calcium-independent PKCs. This combined effect on PKCs seems to be essential for the protection of oocytes from fragmentation. Neither the specific activator of calcium-dependent PKCs 1-oleoyl-2-acetyl-sn-glycerol (OLE) nor the specific activator of calcium-independent PKCs dipalmitoyl-l-α-phosphatidylinositol-3,4,5-triphosphate heptaammonium salt (DIPALM) suppressed the fragmentation of aging pig oocytes. Twenty-one percentage of oocytes fragmented when aged for 3 days in 10 μM OLE and 26% of aged oocytes fragmented in 100 nM of DIPALM. However, fragmentation was significantly suppressed to 7% when the oocytes were exposed to the combination of both 10 μM OLE and 100 nM DIPALM. Aging pig oocytes cultured for 1 day with PMA maintained a high capability of being parthenogenetically activated (86% of activated oocytes), using calcium ionophore with 6-dimethylaminopurine. Ageing oocytes treated with PMA also had high capability of cleavage (82%) after their artificial parthenogenetic activation. However, their ability to develop to the stage of blastocyst (12%) was suppressed when compared with oocytes activated immediately after their maturation (29%).     

Hematologic, protein electrophoresis, biochemistry, and cholinesterase values of free-living black stork nestlings (Ciconia nigra)

Hematologic, protein electrophoresis, serum biochemistry, and cholinesterase values were determined in 36 free-living black stork nestlings (Ciconia nigra) between 25 and 53 days of age in order to establish normal reference values for this population. The following values were evaluated: white blood cell counts, red blood cell counts, packed cell volume, hemoglobin, heterophils, lymphocytes, monocytes, eosinophils, prealbumin, albumin, alpha-globulin, beta-globulin, gamma-globulin, total protein, aspartate aminotransferase, alkaline phosphatase, lactate dehydrogenase, creatine kinase, calcium, phosphorus, iron, cholesterol, glucose, triglycerides, uric acid, urea, creatinine, total solids, bile acids, and butyrylcholinesterase. Sex-dependent differences were observed in hemoglobin, prealbumin, albumin, gamma-globulin, total protein, alkaline phosphatase, and triglycerides. Packed cell volume, butyrylcholinesterase, aspartate aminotransferase, creatine kinase, and creatinine increased with age, whereas albumin, mean cell volume, calcium, phosphorus, cholesterol, and total solids decreased with age. These hematologic and serum biochemistry values can be used as reference ranges in free-living black stork nestlings.     

Deletions of mob and tra pJP4 transfer functions after mating of Ralstonia eutropha JMP134 (pJP4) with Escherichia coli harboring F'::Tn10

One-tenth of Escherichia coli transconjugants resulting from the transfer of the catabolic plasmid pJP4 from Ralstonia eutropha JMP134 to E. coli XL1Blue, contained pJP4 derivatives with deletions (approximately 15-30 kb). The occurrence of these deletions is probably associated with the presence of Tn10 in the recipient. DNA endonuclease restriction analysis of the pJP4 deletion derivatives showed the absence of SphI and EcoRI fragments previously reported to hybridize with IncP Tra DNA probes. Moreover, these pJP4 deletion derivatives are not able to self-transfer, nor are they able to be mobilized. Accordingly, these pJP4 deletion derivatives lack transfer functions.