Skeletal and muscular pelvic morphology of hillstream loaches (Cypriniformes: Balitoridae)

The rheophilic hillstream loaches (Balitoridae) of South and Southeast Asia possess a range of pelvic girdle morphologies, which may be attributed to adaptations for locomotion against rapidly flowing water. Specifically, the connectivity of the pelvic plate (basipterygium) to the vertebral column via a sacral rib, and the relative size and shape of the sacral rib, fall within a spectrum of three discrete morphotypes: long, narrow rib that meets the basipterygium; thicker, slightly curved rib meeting the basipterygium; and robust crested rib interlocking with the basipterygium. Species in this third category with more robust sacral rib connections between the basipterygium and vertebral column are capable of walking out of water with a tetrapod-like lateral-sequence, diagonal-couplet gait. This behavior has not been observed in species lacking direct skeletal connection between the vertebrae and the pelvis. The phylogenetic positions of the morphotypes were visualized by matching the morphological features onto a novel hypothesis of relationships for the family Balitoridae. The morphotypes determined through skeletal morphology were correlated with patterns observed in the pelvic muscle morphology of these fishes. Transitions towards increasingly robust pelvic girdle attachment were coincident with a more anterior origin on the basipterygium and more lateral insertion of the muscles on the fin rays, along with a reduction of the superficial abductors and adductors with more posterior insertions. These modifications are expected to provide a mechanical advantage for generating force against the ground. Inclusion of the enigmatic cave-adapted balitorid Cryptotora thamicola into the most data-rich balitorid phylogeny reveals its closest relatives, providing insight into the origin of the skeletal connection between the axial skeleton and basipterygium.     

Synthesis and in vitro evaluation of small-molecule [18F] labeled gonadotropin-releasing hormone (GnRH) receptor antagonists as potential PET imaging agents for GnRH receptor expression

Two novel small molecule gonadotropin-releasing hormone (GnRH) receptor antagonists (12 and 13) of the furamide-class were synthesized and evaluated in vitro for their receptor binding affinities for the rat GnRH receptor. Radiolabeling with no carrier added fluorine-18 of the appropriate precursors was investigated in a one-step reaction. Log P (Octanol/PBS pH 7.4) and serum stability of the compounds were investigated. The antagonists showed low nM affinity for the rat GnRH receptor. ¹⁸F-radiolabled compounds were obtained in high radiochemical purity (>95%) and specific activity (>75 GBq/μmol). These findings suggest this class of compounds holds promise as potential probes for PET targeting of GnRH-receptor expression.     

A four-dimensional computed tomography comparison of healthy and asthmatic human lungs

The purpose of this study was to explore new insights in non-linearity, hysteresis and ventilation heterogeneity of asthmatic human lungs using four-dimensional computed tomography (4D-CT) image data acquired during tidal breathing. Volumetric image data were acquired for 5 non-severe and one severe asthmatic volunteers. Besides 4D-CT image data, function residual capacity and total lung capacity image data during breath-hold were acquired for comparison with dynamic scans. Quantitative results were compared with the previously reported analysis of five healthy human lungs. Using an image registration technique, local variables such as regional ventilation and anisotropic deformation index (ADI) were estimated. Regional ventilation characteristics of non-severe asthmatic subjects were similar to those of healthy subjects, but different from the severe asthmatic subject. Lobar airflow fractions were also well correlated between static and dynamic scans (R² > 0.84). However, local ventilation heterogeneity significantly increased during tidal breathing in both healthy and asthmatic subjects relative to that of breath-hold perhaps because of airway resistance present only in dynamic breathing. ADI was used to quantify non-linearity and hysteresis of lung motion during tidal breathing. Non-linearity was greater on inhalation than exhalation among all subjects. However, exhalation non-linearity among asthmatic subjects was greater than healthy subjects and the difference diminished during inhalation. An increase of non-linearity during exhalation in asthmatic subjects accounted for lower hysteresis relative to that of healthy ones. Thus, assessment of non-linearity differences between healthy and asthmatic lungs during exhalation may provide quantitative metrics for subject identification and outcome assessment of new interventions.     

MV-mimicking micelles loaded with PEG-serine-ACP nanoparticles to achieve biomimetic intra/extra fibrillar mineralization of collagen in vitro

Since their discovery, matrix vesicles (MVs) containing minerals have received considerable attention for their role in the mineralization of bone, dentin and calcified cartilage. Additionally, MVs' association with collagen fibrils, which serve as the scaffold for calcification in the organic matrix, has been repeatedly highlighted. The primary purpose of the present study was to establish a MVs–mimicking model (PEG-S-ACP/micelle) in vitro for studying the exact mechanism of MVs-mediated extra/intra fibrillar mineralization of collagen in vivo. In this study, high-concentration serine was used to stabilize the amorphous calcium phosphate (S-ACP), which was subsequently mixed with polyethylene glycol (PEG) to form PEG-S-ACP nanoparticles. The nanoparticles were loaded in the polysorbate 80 micelle through a micelle self-assembly process in an aqueous environment. This MVs–mimicking model is referred to as the PEG-S-ACP/micelle model. By adjusting the pH and surface tension of the PEG-S-ACP/micelle, two forms of minerals (crystalline mineral nodules and ACP nanoparticles) were released to achieve the extrafibrillar and intrafibrillar mineralization, respectively. This in vitro mineralization process reproduced the mineral nodules mediating in vivo extrafibrillar mineralization and provided key insights into a possible mechanism of biomineralization by which in vivo intrafibrillar mineralization could be induced by ACP nanoparticles released from MVs. Also, the PEG-S-ACP/micelle model provides a promising methodology to prepare mineralized collagen scaffolds for repairing bone defects in bone tissue engineering.     

Anatomical site of pheromone accumulation and temporal pattern of pheromone emission in the ambrosia beetle Megaplatypus mutatus

Megaplatypus mutatus (Chapuis) is a native South American ambrosia beetle that attacks live hardwood trees (e.g. Populus spp.), causing important economic losses to commercial plantations. Male beetles release the main components of the sex pheromone, namely (+)‐6‐methyl‐5‐hepten‐2‐ol [(+)‐sulcatol, or retusol] and 6‐methyl‐5‐hepten‐2‐one (sulcatone), when colonizing suitable hosts. The hindgut is shown to be the anatomical site of pheromone accumulation within males, the enantiomeric composition of sulcatol in this tissue is 99%‐(+) and sulcatol is first detectable in this tissue on days 1–2 after gallery initiation. Peak accumulation of sulcatol occurs on days 5–12 after gallery initiation. Trace quantities of sulcatone are also observed during the same period. Both pheromone components are present in male emissions from three host species (Populus×canadensis, Populus alba and Casuarina stricta) between days 2 and 12 after gallery initiation, although sulcatone is always present in low concentrations. The temporal patterns of sulcatol and sulcatone accumulation or storage in male M. mutatus correspond to the temporal patterns of emission.     

Rhythms of fragrance emission in flowers

A method for the sampling of volatiles emitted by individual flowers is described. Sampling over periods of 3 h allowed the examination of diurnal changes in quantity and quality of fragrance. In the species studied, Odontoglossum constrictum Lindl., Citrus medica L., Hoya carnosa R. Br., and Stephanotis floribunda Brongs., the fragrance was characterized by a few major components accompanied by a larger number of minor components. Flowers of all species produced volatiles in a rhythmical, diurnal fashion. Whereas in detached flowers of O. constrictum and C. medica rhythmicity could be observed for up to four cycles, flowers of H. carnosa showed this phenomenon only when attached to the plant. Maxima of emission were observed during the day in C. medica and O. constrictum whereas in H. carnosa it occurred during the night. In S. floribunda a conspicuous asynchronism of the emission of different volatiles was observed, resulting in the rhythmical change of fragrance quality.     

Morphology and systematics of anthracomartidae (Arachnida: Trigonotarbida)

Abstract: X‐ray microtomography (XMT) was applied to three species of the extinct arachnid order Trigonotarbida, hosted in siderite nodules from the late Carboniferous British Middle Coal Measures. All three, Cryptomartus hindi ( Pocock, 1911 ), Cleptomartus plautus ( Petrunkevitch, 1949 ) and Maiocercus celticus ( Pocock, 1902 ), belong to the family Anthracomartidae. As well as providing interactive three‐dimensional visualisations of their likely appearance in life, XMT study has resolved new morphological detail, yielding key data about the likely stance and habitus of these early arachnids. Similarities in the form of the carapace, eyes and coxosternal region between anthracomartids and the Devonian genus Palaeocharinus Hirst, 1923 are highlighted. Analogies in limb disposition are drawn between anthracomartids and modern crab spiders (Araneae: Thomisidae), which exhibit sit‐and‐wait style predatory behaviour. Anthracomartids are relatively common fossils at many Coal Measures localities. Although they appear to exhibit limited morphological variation, numerous genera and species have been proposed in the literature, often distinguished from each other on rather trivial characters. From our reconstruction of well‐preserved examples, we have resolved a number of common features likely to be present in a typical anthracomartid. Comparisons to this model suggest that the characters on which many anthracomartid genera are distinguished may be artefacts of preservation. We hence treat Promygale Fri?, 1901 , Brachylycosa Fri?, 1904 , Perneria Fri?, 1904 , Coryphomartus Petrunkevitch, 1945 , Cryptomartus Petrunkevitch, 1945 , Pleomartus Petrunkevitch, 1945 , Cleptomartus Petrunkevitch, 1949 and Oomartus Petrunkevitch, 1953 as junior synonyms of the type genus of the family, Anthracomartus Karsch, 1882 . Only the genera Brachypyge Woodward, 1878 and Maiocercus Pocock, 1911 are additionally retained. Within Anthracomartus, Cleptomartus planus Petrunkevitch, 1949 , Cryptomartus meyeri Guthörl, 1964 , Cleptomartus hangardi Guthörl, 1965 and Cryptomartus rebskei Brauckmann, 1984 are treated as junior synonyms of A. hindi Pocock, 1911 (all syn. nov.). Cleptomartus plautus Petrunkevitch, 1949 and Anthracomartus denuiti Pruvost, 1922 are treated as junior synonyms of A. priesti Pocock, 1911 (both syn. nov.).