Mikrozephaliesyndrome und geistige Behinderung

Clarification of the cause of mental retardation, which has a prevalence of 2–3%, is a common reason for genetic consultation. On the basis of the cardinal sign of microcephaly, which also has a prevalence of 2–3%, an overview on different conditions with developmental delay/mental retardation is given according to the mode of inheritance. The current version of the Winter–Baraitser Dysmorphology Database lists 558 conditions with the combination of microcephaly and developmental delay/mental retardation. This makes clear that the following overview gives only a limited look at the comprehensive field of clinical genetics/dysmorphology.     

Acidocalcisomen,Mitosomen und Apicoplasten. Neu entdeckte Zellorganellen

Three new, membrane‐bounded organelles were detected in the last decade. Acidocalcisomes which occur in pro‐ and eukaryotes are acidic and store calcium, and further also phosphate, oxygen, magnesium, zink, sodium, potassium, and iron. Furthermore, they are engaged in osmoregulation, pH‐ and Ca²⁺‐homeostasis. Mitosomes are strongly reduced mitochondria of different parasitic protists, which were previously grouped as primarily mitochondria‐free organisms. Apicoplasts are the strongly reduced plastids of the parasitic apicomplexans (formerly sporozoa). They are a target for the development of new drugs, e.g. against the cause of malaria, Plasmodium.     

Effectiveness of knowledge brokering and recommendation dissemination for influencing healthcare resource allocation decisions: A cluster randomised controlled implementation trial

BackgroundImplementing evidence into clinical practice is a key focus of healthcare improvements to reduce unwarranted variation. Dissemination of evidence-based recommendations and knowledge brokering have emerged as potential strategies to achieve evidence implementation by influencing resource allocation decisions. The aim of this study was to determine the effectiveness of these two research implementation strategies to facilitate evidence-informed healthcare management decisions for the provision of inpatient weekend allied health services.Methods and findingsThis multicentre, single-blinded (data collection and analysis), three-group parallel cluster randomised controlled trial with concealed allocation was conducted in Australian and New Zealand hospitals between February 2018 and January 2020. Clustering and randomisation took place at the organisation level where weekend allied health staffing decisions were made (e.g., network of hospitals or single hospital). Hospital wards were nested within these decision-making structures. Three conditions were compared over a 12-month period: (1) usual practice waitlist control; (2) dissemination of written evidence-based practice recommendations; and (3) access to a webinar-based knowledge broker in addition to the recommendations. The primary outcome was the alignment of weekend allied health provision with practice recommendations at the cluster and ward levels, addressing the adoption, penetration, and fidelity to the recommendations. The secondary outcome was mean hospital length of stay at the ward level. Outcomes were collected at baseline and 12 months later. A total of 45 clusters (n = 833 wards) were randomised to either control (n = 15), recommendation (n = 16), or knowledge broker (n = 14) conditions. Four (9%) did not provide follow-up data, and no adverse events were recorded. No significant effect was found with either implementation strategy for the primary outcome at the cluster level (recommendation versus control β 18.11 [95% CI −8,721.81 to 8,758.02] p = 0.997; knowledge broker versus control β 1.24 [95% CI −6,992.60 to 6,995.07] p = 1.000; recommendation versus knowledge broker β −9.12 [95% CI −3,878.39 to 3,860.16] p = 0.996) or ward level (recommendation versus control β 0.01 [95% CI 0.74 to 0.75] p = 0.983; knowledge broker versus control β −0.12 [95% CI −0.54 to 0.30] p = 0.581; recommendation versus knowledge broker β −0.19 [−1.04 to 0.65] p = 0.651). There was no significant effect between strategies for the secondary outcome at ward level (recommendation versus control β 2.19 [95% CI −1.36 to 5.74] p = 0.219; knowledge broker versus control β −0.55 [95% CI −1.16 to 0.06] p = 0.075; recommendation versus knowledge broker β −3.75 [95% CI −8.33 to 0.82] p = 0.102). None of the control or knowledge broker clusters transitioned to partial or full alignment with the recommendations. Three (20%) of the clusters who only received the written recommendations transitioned from nonalignment to partial alignment. Limitations include underpowering at the cluster level sample due to the grouping of multiple geographically distinct hospitals to avoid contamination.ConclusionsOwing to a lack of power at the cluster level, this trial was unable to identify a difference between the knowledge broker strategy and dissemination of recommendations compared with usual practice for the promotion of evidence-informed resource allocation to inpatient weekend allied health services. Future research is needed to determine the interactions between different implementation strategies and healthcare contexts when translating evidence into healthcare practice.Trial registrationAustralian New Zealand Clinical Trials Registry ACTRN12618000029291.

In a cluster randomized controlled implementation trial, Dr. Mitchell N Sarkies and colleagues examine the effectiveness of knowledge brokering and recommendation dissemination in influencing healthcare resource allocation decisions in Australia and New Zealand.     

First indication of gas embolism in a harbour porpoise (Phocoena phocoena) from German waters

In the last decade, a number of cetacean strandings have gas embolic pathology analogous to decompression sickness in man and experimental animals. Acute gas and fat embolic lesions have also been found in mass-stranded beaked whales causally linked to high-intensity anthropogenic mid-frequency sonar activities. Sporadic chronic gas embolic lesions have also been described. This communication describes a first case of numerous gas-filled fibrous cavities in the markedly enlarged liver of a dead adult male harbour porpoise stranded at the North Sea coast of Schleswig-Holstein, Germany. Additional pathological findings consisted of chronic parasitic granulomatous cholangiohepatitis, hepatic vein thrombosis, parasitic infestations of the bronchial tree and pulmonary blood vessels associated with bronchopneumonia and severe parasitic burden in both ear sinuses. The hepatic cavernous lesions are similar to those described in chronic gas bubble disease in other cetaceans, most likely resulting from decompression-related tissue supersaturation with nitrogen.     

Effects of honeydew and insecticide residues on the distribution of foraging aphid parasitoids under glasshouse and field conditions

The opposing effects of attraction to host-derived kairomones and repellency from the pyrethroid insecticide deltamethrin were investigated with aphid parasitoids from the genus Aphidius (Hymenoptera: Aphidiinae). The spatial distribution of female parasitoids was recorded in a series of experiments conducted in a small glasshouse containing wheat plants either infested with cereal aphids, Sitobion avenae (F.) (Homoptera: Aphididae), uninfested or treated with the recommended field concentration of deltamethrin. The number of parasitoids per plant were counted at 0.5 h, 1 h and then at one hourly intervals up to 8 h after release. Parasitoids showed a strong aggregation response to aphid-infested plants compared to adjacent uninfested plants. With the introduction of insecticidetreated plants around the aphid-infested plants, parasitoids showed a greater tendency to disperse away, resulting in fewer parasitoids on plants and significantly lower rates of aphid parasitism. The degree of aphid fall-off from plants was a good indicator of parasitoid foraging activity. In field studies, using sticky traps to measure the activity of parasitoids in plots sprayed with water, deltamethrin and/or an artificial honeydew solution, repellent properties were evident for up to 2 days after application. The attraction/arrestment stimuli associated with the honeydew solution were sufficient for parasitoids to continue searching insecticide-treated areas. The implications of these findings for parasitoids searching crops contaminated with aphid-derived kairomones and insecticides are discussed.     

Selective binding and transcytosis of Ulex europaeus 1 lectin by mouse Peyer's patch M-cells in vivo

The in vivo interaction of the lectin Ulex europaeus agglutinin 1 with mouse Peyer's patch follicle-associated epithelial cells was studied in the mouse Peyer's patch gut loop model by immunofluorescence and electron microscopy. The lectin targets to mouse Peyer's patch M-cells and is rapidly endocytosed and transcytosed. These processes are accompanied by morphological changes in the M-cell microvilli and by redistribution of polymerised actin. The demonstration of selective binding and uptake of a lectin by intestinal M-cells in vivo suggests that M-cell-specific surface glycoconjugates might act as receptors for the selective adhesion/uptake of microorganisms.This work was supported under the LINK programme in Selective Drug Delivery and Targeting, funded by SERC/MRC/DTI and industry (SERC grant GR/F 09747). M.A.J. was also supported by a Wellcome Postdoctoral Research Followship (039684/Z/93/Z). Additional support was provided by the Royal Society for equipment.     

Do seasonal changes in numbers of aerially dispersing spiders reflect population density on the ground or variation in ballooning motivation?

Groups of linyphiid spiders (Erigone spp.) (Araneae, Linyphiidae), collected at intervals from arable land, were tested in laboratory bioassays to determine the proportion of individuals that exhibited ballooning behaviour on each field sampling occasion. There was no significant variation in the proportions of spiders in each test group ballooning in the laboratory over a year. Investigations of ground density and aerial dispersal, in a grass field and a winter-wheat field, confirmed that peaks in numbers of spiders observed ballooning in the field generally coincided with population peaks in the summer and autumn. Significant correlations between ground populations and aerial catches were found for total spiders, immature spiders, and Bathyphantes gracilis (Blackwall) in both fields, adult spiders in the grass field, Erigone spp. in the grass, and Meioneta rurestris (C.L. Koch) in the wheat. The other groups analysed, Lepthyphantes tenuis (Blackwall) in both fields, Erigone spp. in wheat, and M. rurestris in grass, showed similar but non-significant trends. No significant difference was found between overall ground-to-air ratios for males compared to females, but adult spiders were more likely to balloon than immatures.     

Characterization of the safener-induced glutathione S-transferase isoform II from maize

The safener-induced maize (Zea mays L.) glutathione S-transferase, GST II (EC 2.5.1.18) and another predominant isoform, GST I, were purified from extracts of maize roots treated with the safeners R-25788 (N,N-diallyl-2-dichloroacetamide) or R-29148 (3-dichloroace-tyl-2,2,5-trimethyl-1,3-oxazolidone). The isoforms GST I and GST II are respectively a homodimer of 29-kDa (GST-29) subunits and a heterodimer of 29 and 27-kDa (GST-27) subunits, while GST I is twice as active with 1-chloro-2,4-dinitrobenzene as GST II, GST II is about seven times more active against the herbicide, alachlor. Western blotting using antisera raised against GST-29 and GST-27 showed that GST-29 is present throughout the maize plant prior to safener treatment. In contrast, GST-27 is only present in roots of untreated plants but is induced in all the major aerial organs of maize after root-drenching with safener. The amino-acid sequences of proteolytic fragments of GST-27 show that it is related to GST-29 and identical to the 27-kDa subunit of GST IV.Abbreviations CDNB 1-chloro-2,4-dinitrobenzene - DEAE di-ethylaminoethyl - FPLC fast protein liquid chromatography - GSH reduced glutathione - GST glutathione S-transferase - GST-26 26-kDa subunit of maize GST - GST-27 27-kDa subunit of maize GST - GST-29 29-kDa subunit of maize GST - R-25788 safener N,N-diallyl-2-dichloroacetamide - R-29148 safener 3-dichloroacetyl-2,2,5-trimethyl-1,3-oxazolidone - RPLC reverse phase liquid chromatography We are grateful to M-M. Lay, ZENECA AG Products (formerly ICI Americas), Richmond, Calif., USA for providing [¹⁴C] R-25788. ZENECA Seeds in the UK is part of ZENECA Limited.