Phylogenetic signals in thermal traits remain stronger in the tropics if we can believe published physiological data. A reply to McKechnie et al., “Data quality problems undermine analyses of endotherm upper critical temperatures”

Due to concerns about data quality, McKechnie, Coe, Gerson, and Wolf ( 2016 ) questioned the conclusions of our study (Khaliq et al., 2015 ) published in this journal. Here, we argue that most of the questioned data points are in fact useful for macrophysiological analyses, mostly because the vast majority of data are explicitly reported in the peer‐reviewed physiological literature. Furthermore, we show that our conclusions remain largely robust irrespective of the data inclusion criterion. While we think that constructive debates about the adequate use of primary data in meta‐studies as well as more transparency in data inclusion criteria are indeed useful, we also emphasize that data suitability should be evaluated in the light of the scope and scale of the study in which they are used. We hope that this discussion will not discourage the exchange between disciplines such as biogeography and physiology, as this integration is needed to address some of the most urgent scientific challenges.     

Insulin-Like Growth Factor 1 (IGF-1) in Parkinson's Disease: Potential as Trait-, Progression- and Prediction Marker and Confounding Factors

Introduction

Biomarkers indicating trait, progression and prediction of pathology and symptoms in Parkinson''s disease (PD) often lack specificity or reliability. Investigating biomarker variance between individuals and over time and the effect of confounding factors is essential for the evaluation of biomarkers in PD, such as insulin-like growth factor 1 (IGF-1).

Materials and Methods

IGF-1 serum levels were investigated in up to 8 biannual visits in 37 PD patients and 22 healthy controls (HC) in the longitudinal MODEP study. IGF-1 baseline levels and annual changes in IGF-1 were compared between PD patients and HC while accounting for baseline disease duration (19 early stage: ≤3.5 years; 18 moderate stage: >4 years), age, sex, body mass index (BMI) and common medical factors putatively modulating IGF-1. In addition, associations of baseline IGF-1 with annual changes of motor, cognitive and depressive symptoms and medication dose were investigated.

Results

PD patients in moderate (130±26 ng/mL; p = .004), but not early stages (115±19, p>.1), showed significantly increased baseline IGF-1 levels compared with HC (106±24 ng/mL; p = .017). Age had a significant negative correlation with IGF-1 levels in HC (r = -.47, p = .028) and no correlation in PD patients (r = -.06, p>.1). BMI was negatively correlated in the overall group (r = -.28, p = .034). The annual changes in IGF-1 did not differ significantly between groups and were not correlated with disease duration. Baseline IGF-1 levels were not associated with annual changes of clinical parameters.

Discussion

Elevated IGF-1 in serum might differentiate between patients in moderate PD stages and HC. However, the value of serum IGF-1 as a trait-, progression- and prediction marker in PD is limited as IGF-1 showed large inter- and intraindividual variability and may be modulated by several confounders.     

Kinetics control preferential heterodimer formation of platelet-derived growth factor from unfolded A- and B-chains

The folding and assembly of platelet-derived growth factor (PDGF), a potent mitogen involved in wound-healing processes and member of the cystine knot growth factor family, was studied. The kinetics of the formation of disulfide-bonded dimers were investigated under redox reshuffling conditions starting either from unfolded and reduced PDGF-A- or B-chains or an equimolar mixture of both chains. It is shown that in all cases the formation of disulfide-bonded dimers is a very slow process occurring in the time scale of hours with a first-order rate-determining step. The formation of disulfide-bonded PDGF-AA or PDGF-BB homodimers displayed identical kinetics, indicating that both monomeric forms as well as the dimerized homodimer have similar folding and assembly pathways. In contrast, the formation of the heterodimer occurred three times more rapidly compared with the formation of the homodimers. As both monomeric forms revealed similar renaturation kinetics, it can be concluded that the first-order rate-determining folding step does not occur during monomer folding but must be attributed to conformational rearrangements of the dimerized, not yet disulfide-bonded protein. These structural rearrangements allow a more rapid formation of intermolecular disulfide bonds between the two different monomers of a heterodimer compared with the formation of the disulfide bonds between two identical monomers. The preferential formation of disulfide-bonded heterodimers from an equimolar mixture of unfolded A- and B-chains is thus a kinetically controlled process. Moreover, similar activation enthalpies for the formation of all different isoforms suggest that faster heterodimerization is controlled by entropic factors.     

Bioanalytical application of surface‐ and tip‐enhanced Raman spectroscopy

Due to its fingerprint specificity and trace‐level sensitivity, surface‐enhanced Raman spectroscopy (SERS) is an attractive tool in bioanalytics. This review reflects the research in this highly interesting topic of the last 3–4 years. The detection of the SERS signature of biomolecules up to microorganisms and cells is introduced. Labeling using modified nanoparticles (SERS tags) is also introduced. In order to establish biomedical applications, SERS analysis is performed in complex matrices such as body fluids. Furthermore, the SERS technique is combined with other methods such as microfluidic devices for online monitoring and scanning probe microscopy (i.e. tip‐enhanced Raman spectroscopy, TERS) to investigate nanoscaled features. The present review illustrates the broad application fields of SERS and TERS in bioanalytics and shows the great potential of these methods for biomedical diagnostics.     

Derivation of 30 human embryonic stem cell lines—improving the quality

We have derived 30 human embryonic stem cell lines from supernumerary blastocysts in our laboratory. During the derivation process, we have studied new and safe method to establish good quality lines. All our human embryonic stem cell lines have been derived using human foreskin fibroblasts as feeder cells. The 26 more recent lines were derived in a medium containing serum replacement instead of fetal calf serum. Mechanical isolation of the inner cell mass using flexible metal needles was used in deriving the 10 latest lines. The lines are karyotypically normal, but culture adaptation in two lines has been observed. Our human embryonic stem cell lines are banked, and they are available for researchers.     

Head morphology of <Emphasis Type="Italic">Osmylus fulvicephalus</Emphasis> (Osmylidae,Neuroptera) and its phylogenetic implications

External and internal head structures of Osmylus fulvicephalus were examined and described in detail. Exo- and endoskeleton, musculature, elements of the central nervous system and tracheae are compared to conditions found in other groups of Neuropterida and other endopterygote lineages. Thirty-six adult cephalic characters were compiled, combined in a datamatrix with 64 characters of the larval head, and analysed cladistically. Mainly because many data on adults remain missing, most branches in the cladogram are mostly or exclusively supported by larval features. The shortening of the mesal mandibular wall and the resulting anterior shift of the adductor tendon possibly constitute an adult groundplan apomorphy of Neuropterida. Raphidioptera and Megaloptera share distinct prognathism and the presence of a sclerotised gula. However, the orthognathous head and the absence of a gula resulted as autapomorphies of Neuroptera in our analyses. Further potential autapomorphies are the asymmetry of the mandibles as well as the respective presence of dorsolateral furrows on the head capsule, of a shovel-like extension on the ventral mandibular cutting edge, and of a row of stiff hairs on the mandible’s ventral surface. The systematic affinities of Osmylidae remain ambiguous. Osmylus is mainly characterised by plesiomorphic features of the adult head such as a complete endoskeleton, long filiform antennae, largely unmodified orthopteroid mouthparts, and particularly the nearly complete set of muscles. The placement with a clade also comprising Hemerobiidae and Chrysopidae is poorly supported. The presence of a dense vestiture of long microtrichia on the distal galeomere resulted as a synapomorphy of the three families. An apparent plesiomorphy preserved in Osmylus but absent in all other groups of Neuroptera is the presence of well developed ocelli. The present study underlines the severe shortage of detailed morphological data on the adults. Intensive study of adult structures is required for a solid reconstruction of the phylogeny of Neuropterida, especially of the hemerobiform lineage of Neuroptera.     

Investigating the horizontal transmission of the Cydia pomonella granulovirus (CpGV) in a model system

Repeated applications of Cydia pomonella granulovirus (CpGV) can effectively control the codling moth (CM) in apple orchards. However, it is still unknown whether horizontal transmission of the virus from infected to uninfected larvae contributes to the efficacy of the virus insecticide. Horizontal transmission of CpGV was assayed using detached apples. In experiments using artificially applied virus dots on the apple’s surface or infected CM larvae as virus inoculum, it was found that the likelihood of infection of healthy CM larvae relied mainly on the larval behavior. The amount of virus inoculum, either applied artificially or produced by the infected larvae, impacted the infection rate only to a small degree. In the experiments, CM larvae exhibited a strong preference in entry sites, increasing the chance for horizontal transmission. Depending on the experimental design, horizontal transmission rates of about 40% were observed in laboratory assays.     

Influence of UV-B radiation and nitrogen starvation on daily rhythms in phototaxis and cell shape of Euglena gracilis

The flagellate Euglena gracilis Klebs strain Z shows phototaxis and changes cell shape between oblong and round. Both cell events show daily rhythmicity. Phototaxis was highest about 2 h after light onset with a second peak of activity 9 h later. At the same times, the cells were in their most oblong shape. During the night phase the cells were phototactically inactive and round. These rhythms were altered by environmental stress, e.g. UV-B radiation (280–320 nm) and nitrogen deficiency. Artificial UV-B radiation of 0.5 W m⁻² caused a loss in phototaxis hut the peak of activity occurred at the same time as for control cells. The transition from round to oblong cell shape was slower after UV-B radiation, but the difference between the roundest and the most oblong cell shape was unchanged. Nitrogen deficiency caused a total loss of phototaxis and the cells remained round all the time. The cells lost all their chlorophyll and were, therefore, photosynthetically inactive.