Insecticide and fungicide effect on thermal and olfactory behavior of bees and their disappearance in bees’ tissues

Plant protection products may affect the behavior of organisms which are not a target of control. The effect of Karate Zeon 050 CS (λ-Cyhalothrin -based insecticide; λ-CBI) and Amistar 250 SC (Azoxystrobin-based fungicide; ABF) was determined on Apis mellifera worker attraction towards their own colony odour, along with temperature preferences. Bees exposed to pesticides prefer the environment with the odour of their nest less often than the control group, and that insecticide-treated bees chose warmer environments than the control insects. The observed differences in the bees, especially with attraction towards their own colony, were dependent on the time of day. Chromatographic analyses indicated that λ-Cyhalothrin elimination was half that of Azoxystrobin in bee organisms, and both agents retarded each other’s clearance. Mathematical modeling estimated that despite a relatively high disappearance rate, both compounds might have been bio-accumulated at relatively high level.     

Diffusion MRI detects early brain microstructure abnormalities in 2‐month‐old 3×Tg‐AD mice

The 3×Tg‐AD mouse is one of the most studied animal models of Alzheimer's disease (AD), and develops both amyloid beta deposits and neurofibrillary tangles in a temporal and spatial pattern that is similar to human AD pathology. Additionally, abnormal myelination patterns with changes in oligodendrocyte and myelin marker expression are reported to be an early pathological feature in this model. Only few diffusion MRI (dMRI) studies have investigated white matter abnormalities in 3×Tg‐AD mice, with inconsistent results. Thus, the goal of this study was to investigate the sensitivity of dMRI to capture brain microstructural alterations in 2‐month‐old 3×Tg‐AD mice. In the fimbria, the fractional anisotropy (FA), kurtosis fractional anisotropy (KFA), and radial kurtosis (K_┴) were found to be significantly lower in 3×Tg‐AD mice than in controls, while the mean diffusivity (MD) and radial diffusivity (D_┴) were found to be elevated. In the fornix, K_┴ was lower for 3×Tg‐AD mice; in the dorsal hippocampus MD and D_┴ were elevated, as were FA, MD, and D_┴ in the ventral hippocampus. These results indicate, for the first time, dMRI changes associated with myelin abnormalities in young 3×Tg‐AD mice, before they develop AD pathology. Morphological quantification of myelin basic protein immunoreactivity in the fimbria was significantly lower in the 3×Tg‐AD mice compared with the age‐matched controls. Our results demonstrate that dMRI is able to detect widespread, significant early brain morphological abnormalities in 2‐month‐old 3×Tg‐AD mice.     

Anatomy and White Matter Connections of the Superior Frontal Gyrus

The superior frontal gyrus (SFG) is an important region implicated in a variety of tasks including motor movement, working memory, resting-state, and cognitive control. A detailed understanding of the subcortical white matter of the SFG could improve postoperative morbidity related to surgery around this gyrus. Through DSI-based fiber tractography validated by gross anatomical dissection, we characterized the fiber tracts of the SFG based on their relationships to other well-known neuroanatomic structures. Diffusion imaging from the Human Connectome Project from 10 healthy adult subjects was used for fiber tractography. We evaluated the SFG as a whole based on its connectivity with other regions. All tracts were mapped in both hemispheres, and a lateralization index was calculated based on resultant tract volumes. Ten cadaveric dissections were then performed using a modified Klingler technique to delineate the location of major tracts integrated within the SFG. We identified four major SFG connections: the frontal aslant tract connecting to the inferior frontal gyrus; the inferior fronto-occipital fasciculus connecting to the cuneus, lingual gyrus, and superior parietal lobule; the cingulum connecting to the precuneus and parahippocampal gyrus/uncus; and a callosal fiber bundle connecting the SFG bilaterally. The functional networks of the SFG involve a complex series of white matter tracts integrated within the gyrus, including the FAT, IFOF, cingulum, and callosal fibers. Postsurgical outcomes related to this region may be better understood in the context of the fiber-bundle anatomy highlighted in this study. Clin. Anat. 33:823–832, 2020. © 2019 Wiley Periodicals, Inc.     

Understanding heterogeneity in grey matter research of adults with childhood maltreatment—A meta-analysis and review

Childhood trauma has been associated with long term effects on prefrontal-limbic grey matter. A literature search was conducted to identify structural magnetic resonance imaging studies of adults with a history of childhood trauma. We performed three meta-analyses. Hedges’ g effect sizes were calculated for each study providing hippocampal or amygdala volumes of trauma and non-trauma groups. Seed based differential mapping was utilised to synthesise whole brain voxel based morphometry (VBM) studies. A total of 38 articles (17 hippocampus, 13 amygdala, 19 whole brain VBM) were included in the meta-analyses. Trauma cohorts exhibited smaller hippocampus and amygdala volumes bilaterally. The most robust findings of the whole brain VBM meta-analysis were reduced grey matter in the right dorsolateral prefrontal cortex and right hippocampus amongst adults with a history of childhood trauma. Subgroup analyses and meta-regressions showed results were moderated by age, gender, the cohort’s psychiatric health and the study’s definition of childhood trauma. We provide evidence of abnormal grey matter in prefrontal-limbic brain regions of adults with a history of childhood maltreatment.     

Amorphous silica coatings on magnetic nanoparticles enhance stability and reduce toxicity to in vitro BEAS-2B cells

Background: Nanoparticles are being rapidly assimilated into numerous research fields and consumer products. A concurrent increase in human exposure to such materials is expected. Magnetic nanoparticles (MNPs) possess unique and beneficial features, increasing their functionality and integrative potential. However, MNP toxicity characterization is limited, especially in regards to the human respiratory system. This study aimed to assess the in vitro effects of airborne MNPs on BEAS-2B cells. Uncoated iron oxide was compared with two amorphous silica-coated MNPs, hypothesizing the coatings reduced toxicity and increased particle stability.

Method: BEAS-2B cells were cultured at an air–liquid interface and exposed to airborne MNPs using a fabricated exposure device. Indices of cytotoxicity, inflammatory response, oxidative stress, and iron homeostasis were monitored postexposure via cell viability assays and qRT-PCR. Concentrations of soluble iron-associated with different MNPs were also examined before and after contact with several aqueous organic and inorganic acids.

Results: The silica-coated MNPs had reduced soluble iron concentrations. This result indicates that the silica coating provides a barrier to and prevents the mobilization of soluble iron from the particle to the cell, thereby reducing the risk of oxidative stress or alterations of iron homeostasis. Cells exposed to MagSilica50 and MagSilica50–85® showed little to no indications of cytotoxicity or induction of inflammatory response/oxidative stress at the examined delivery concentrations.

Conclusion: MNPs coated with amorphous silica are protected from acidic erosion. Correspondingly, the particle stability translates into reduced cytotoxicity and cellular influence on human airway epithelial cells.     

Excessive Lowering of Blood Pressure Is Not Beneficial for Progression of Brain White Matter Hyperintensive and Cognitive Impairment in Elderly Hypertensive Patients: 4-Year Follow-Up Study

ObjectivesThis study was designed to explore the appropriate blood pressure (BP) target required to reduce cognitive decline and brain white matter lesions (WMLs) in elderly hypertensive patients.MethodsElderly patients (n = 294, ≥80 years of age) being treated for hypertension were enrolled in a longitudinal study examining cognitive impairment after an initial assessment and a period of 4 years. All patients underwent neurological and cognitive assessment, laboratory examination, and magnetic resonance imaging of the brain.ResultsThe 4-year follow-up examination revealed that body mass index, alcohol consumption, systolic blood pressure (SBP), diastolic blood pressure, and Mini-Mental State Examination (MMSE) all showed a significant decline, whereas fasting plasma glucose, white matter hyperintensities (WMH) volume, and the WMH/total intracranial volume (TIV) ratio were significantly increased when compared with baseline observations. Interestingly, the decline in MMSE, as well as the increment of WMH and WMH/TIV ratio was smaller in patients with SBP ranging from 140 to 160 mm Hg than in those whose SBP was lower than 140 mm Hg or higher than 160 mm Hg (P < .05). Furthermore, we observed that a 15 to 35 mm Hg targeted lowering of SBP in the elderly patients was more beneficial to our cognitive analysis than treatments that achieved less than 15 mm Hg or greater than 35 mm Hg (P < .05).ConclusionsIn elderly hypertensive patients, there exists a beneficial target for SBP lowering beyond which treatment may not be beneficial for improving or delaying the progression of cognitive impairment and WMLs.     

Fascículos asociativos ínsulo-operculares: revisión de su anatomía y de las implicaciones para el abordaje transopercular a la ínsula

IntroductionThe insula is a highly connected area, as an intricate network of afferent and efferent projections connect it with adjacent and distant cortical regions.ObjectiveTo perform an extensive review of recent literature to analyse the anatomy of the associative tracts related to the insula.ResultsThe frontal aslant tract, arcuate fasciculus, horizontal portion of the superior longitudinal fasciculus and the middle longitudinal fasciculus are associative tracts connected to the opercula. The inferior fronto-occipital fasciculus (IFOF) and uncinate fasciculus run under the anterior and inferior portion of the insula.Conclusionsthe pars triangularis and orbicularis of the inferior frontal gyrus, as well as the middle and anterior part of the superior temporal gyrus, have few connections with the perisylvian associative network. Consequently, in the trans-opercular approach to the insula, these 2 regions represent anatomical corridors that give access to the insula. The IFOF and the uncinate fasciculus represent the deep functional margin of resection.     

Numbers and Letters: Exploring an Autistic Savant’s Unpractised Ability

This paper describes an individual with autism and high-level calendar calculation ability who could perform a set of unpractised letter/number association tasks. The savant’s performance was compared with that of two control participants, one a departmental secretary and the other a professor of mathematics. The facility with which the savant could master the rules governing the relationships between the series of items suggests that he possessed a flexibility of mental processing transcending his ability of calendar calculation. Furthermore, he could recalibrate previous knowledge to solve new hitherto unpractised tasks. When presented with novel problems, the savant, unlike the mathematician, made no initial errors at all on any of the presented tasks, thereby indicating his fast and spontaneous recognition of new rules and of new relationships between items. It is concluded that a cognitive style of ‘weak central coherence’ as adopted by autistic savants may protect single representations from being retained in the form of stable enduring wholes, and that such a segmentation strategy may allow for the transformation, reorganization and reconstruction of the relationship between single items of information.