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Organisms can uptake minerals, shape them in different forms and generate teeth, skeletons or shells that support and protect them. Mineral uptake, trafficking and nucleation are tightly regulated by the biomineralizing cells through networks of specialized proteins. Specifically, matrix metalloproteases (MMPs) digest various extracellular substrates and allow for mineralization in the vertebrates' teeth and bones, but little is known about their role in invertebrates' systems. The sea urchin embryo provides an excellent invertebrate model for genetic and molecular studies of biomineralization. MMP inhibition prevents the growth of the calcite spicules of the sea urchin larval skeleton, however, the molecular mechanisms and genes that underlie this response are not well understood. Here we study the spatial expression and regulation of two membrane type MMPs that were found to be occluded in the sea urchin spicules, Pl-MmpL7 and Pl-MmpL5, and investigate the function of Pl-MmpL7 in skeletogenesis. The inhibition of MMPs does not change the volume of the calcium vesicles in the skeletogenic cells. The expression of Pl-MmpL7 and Pl-MmpL5 is regulated by the Vascular Endothelial Growth Factor (VEGF) signaling, from the time of skeleton initiation and on. The expression of these genes is localized to the subsets of skeletogenic cells where active spicule growth occurs throughout skeletogenesis. Downregulation of Pl-MmpL7 expression delays the growth of the skeletal rods and in some cases, strongly perturbs skeletal shape. The localized expression of Pl-MmpL7 and Pl-MmpL5 to the active growth zone and the effect of Pl-MmpL7 perturbations on skeletal growth, suggest that these genes are essential for normal spicule elongation in the sea urchin embryo.

The nematode parasite Neoascarophis mariae was collected from the intestine of Parupeneus forsskali and Mulloidichthys flavolineatus from the Red Sea in Egypt and was described using both light and scanning electron microscopy. It is mainly characterized by the presence of four submedian labia surrounded the oral aperture in the outer side, two sublabia and two pseudolabia in the inner side, rounded cephalic end, and short vestibule in both sexes. The females vulva is located near the posterior end of the body, their oval uterine eggs have a smooth surface devoid of filaments. Males have bifurcated deirids, a large left spicule (85–425 µm) with a tapered tip, and a short right spicule (50–181 µm) with a broad and rounded tip.

This study was aimed at describing two (2) intestinal nematodes from naturally infected native breed of goats (Capra hircus) in Bangladesh, identified as Oesophagostomum columbianum (Curtice, 1890) Stossich 1899 and Haemonchus contortus (Rudolphi, 1803) Cobb, 1898. The identification was made based on morphometric features and was confirmed by amplifying internal transcribed spacer (ITS) and cytochrome c oxidase (cox1) gene. Well-developed lateral alae, distinct cervical papillae anteriorly to esophageal expansion, and male spicule length (0.73-0.79 mm,n=2) were characteristically observed in O. columbianum. At the same time, male spicule length (0.40-0.46 mm,n=2) and position of female vulvar flap (4.30-4.54 mm from posterior end,n=3) were observed in H. contortus. DNA sequence homology of the ITS and cox1 gene of both specimens revealed the same results, showing similarity to the GenBank sequences of O. columbianum (GenBank No. KC715827; JX188470) and H. contortus (GenBank No. KJ724377; HQ389229). Phylogenetic analysis computed by maximum livelihood (ML) from the ITS nucleotide sequences revealed that the O. columbianum and H. contortus isolates identified in this study were clustered in the same clade with isolates from China and Iran, respectively. This study, for the first time, illustrates the characteristics of O. columbianum and H. contortus in Bangladesh, combining both morphological and molecular data. The universal primer-based polymerase chain reaction (PCR) protocol could be an economical and efficient option for researchers from poor resource settings for precise identification of nematodes. The information generated in this study may contribute to formulating effective control strategies against these nematodes.

A new species of entomopathogenic nematodes, Steinernema sandneri n. sp., was recovered by baiting from Poland. Its morphological traits indicate that the new species is a member of the feltiae-kraussei group. A body length of 843 (708–965) μm, a more anterior position of excretory pore (56 μm), and the lower D% value (40 vs > 46) discriminate this species from most of the other group members. The first-generation males of S. sandneri n. sp. can be distinguished from the other clade members by a 60 μm long spicule, a relatively long gubernaculum (GS% = 79), and the position of the excretory pore (80 μm). Phylogenetic analysis of the ITS rDNA, D2D3 of 28 S rDNA, and cox1 sequences confirmed that S. sandneri n. sp. is a new species of the feltiae-kraussei group, closely related to S. kraussei and S. silvaticum.

International audience; Based on light and scanning electron microscopical studies, a new nematode parasite, Paracapillaria (Paracapillaria) gastrica n. sp. (Capillariidae), is described from the stomach of the marine fish (variegated lizardfish) Synodus variegatus (Lacépède) (Aulopiformes: Synodontidae) from off New Caledonia. This species is mainly characterised by the length of the spicule (267 µm), the proximal spicule end expanded to form a conspicuous folded, lobular rim, the presence of a well-developed caudal bursa supported by two lateral projections (rays) not adhering to the posterior border of body and by the size of eggs (54-60 9 24-27 µm) with non-protruding polar plugs. Paracapillaria gastrica n. sp. is the first known capillariid species parasitic in a host belonging to the fish order Aulopiformes and the first species of this genus reported from fishes in New Caledonian waters and the South Pacific Ocean.

Nematode spicules vary in shape and size even between closely related species and, therefore, constitute key characters in nematode taxonomy for distinguishing between species. Spicules are seldom measured on fresh specimens, but rather at some time after extraction from culled hosts and after a period of preservation of the worms in chemical fixatives or by freezing. We carried out two experiments to assess the effects of freezing in Hanks’ balanced salt solution, 70% or 80% ethanol and 10% formalin (both of the latter at room temperature and after storage at −80°C) on spicule length of Heligmosomoides bakeri at two time intervals after extraction from mice (Experiment 1, one and four weeks; Experiment 2, one and four months). In Experiment 1, no significant differences were detected, although there was some variation between treatments and over time. In Experiment 2, spicule length varied significantly between treatments and over time, the greatest shrinkage being in 80% ethanol and the least in 10% formalin. However, overall variation in spicule length was very limited, accounting for no more than 5.03% change in length over time and 4.95% between treatments at any of the periods of assessment. Therefore, while whole nematodes can shrivel and shrink in preservatives, making many measurements unreliable, our data indicated that spicule lengths are very little changed by preservation techniques over time, and so spicule length remains as a reliable taxonomic character.

Introduction The coccyx is well-known to be a highly variable structure considering its morphology. To our knowledge, the relationship between the coccygeal types and other morphological features has not been studied yet. In addition to the interrelations among morphological parameters, this study investigated the morphology and morphometry of coccyx more extensively in the adult Turkish population using computerized tomography images. Methods Five hundred subjects who underwent pelvic computerized tomography were included in this study. In addition to coccyx type and the counts of coccygeal vertebrae and segments, the presence of coccygeal deviation, sacrococcygeal joint (SCJ) fusion, SCJ subluxation, intercoccygeal joint (ICJ) fusion, and coccygeal spicule were evaluated. The coccygeal length, sacrococcygeal angle, and intercoccygeal angle were measured on the digital workstation. The findings were subjected to statistical analyses. Results The coccygeal vertebra count ranged between three to five, with an average of 4.04 ± 0.48. The range of coccygeal segment count was between one and five, with an average of 2.53 ± 1.02. ICJ fusion in any segment, SCJ fusion, and SCJ subluxation were identified in 397 subjects (79.4%), 343 subjects (68.6%), and 17 subjects (3.4%), respectively. The coccyx types from the most common to the least common were as follows: type 2, type 1, type 3, type 4, and type 5. Coccygeal deviation to the left side was observed in 71 subjects (14.2%), while coccygeal deviation to the right side was observed in 61 subjects (12.2%). A coccygeal spicule was identified in 73 subjects (14.6%). The subjects’ mean age demonstrated no significant difference considering the ICJ fusion (p=0.271), SCJ subluxation (p=0.51), coccygeal spicule (p=0.337), features of coccygeal deviation (p=0.83), and coccyx types (p=0.11). The subjects with SCJ fusion (50.7 ± 18.3 years) were significantly older than the subjects without SCJ fusion (46.5 ± 18.5 years) (p=0.016). The differences between the coccyx types considering the rate of SCJ fusion (p=0.002), ICJ fusion (p=0.04), and spicule presence (p

Made available in DSpace on 2022-04-29T08:46:16Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-11-12 A new nematode species, Rhabdochona (Rhabdochona) fuscovaria sp. n. (Rhabdochonidae), is described based on specimens collected from the stomach of the snouted treefrog Scinax fuscovarius (Hylidae) in the So Sebastio do Paraso farm, municipality of Boa Esperan do Sul, southeastern Brazil. This species is characterized by deirids small, simple and stylet shaped, prostom funnel-shaped with 14 teeth, conspicuous left spicule (585.7 m), distal tip slightly widened, moderately dilated, right spicule (132.9 m), boat-shaped, without dorsal barb at the distal tip, 18 pairs of caudal papillae (9 pairs precloacal and 9 pairs postcloacal), and nonfilamented eggs. This is the fourth species described for South America and the 13th for the Neotropical Region. Division of Parasitology So Paulo State University Research and Teaching Laboratory of Wild Animals So Paulo, Campus Botucatu Brazil Laboratrio de Histologia e Embriologia Animal, Instituto da Sade e Produo Animal, Universidade Federal Rural da Amaznia, Belm, Par, Brasil. . user@example.com

Biomineralization is the process in which soft organic tissues use minerals to produce shells, skeletons and teeth for various functions such as protection and physical support. The ability of the cells to control the time and place of crystal nucleation as well as crystal orientation and stiffness is far beyond the state-of-the art of human technologies. Thus, understanding the biological control of biomineralization will promote our understanding of embryo development as well as provide novel approaches for material engineering. Sea urchin larval skeletogenesis offers an excellent platform for functional analyses of both the molecular control system and mineral uptake and deposition. Here we describe the current understanding of the genetic, molecular and cellular processes that underlie sea urchin larval skeletogenesis. We portray the regulatory genes that define the specification of the skeletogenic cells and drive the various morphogenetic processes that occur in the skeletogenic lineage, including: epithelial to mesenchymal transition, cell migration, spicule cavity formation and mineral deposition into the spicule cavity. We describe recent characterizations of the size, motion and mineral concentration of the calcium-bearing vesicles in the skeletogenic cells. We review the distinct specification states within the skeletogenic lineage that drive localized skeletal growth at the tips of the spicules. Finally, we discuss the surprising similarity between the regulatory network and cellular processes that drive sea urchin skeletogenesis and those that control vertebrate vascularization. Overall, we illustrate the novel insights on the biological regulation and evolution of biomineralization, gained from studies of the sea urchin larval skeletogenesis.

Otopetrins comprise a family of proton-selective channels that are critically important for the mineralization of otoliths and statoconia in vertebrates but whose underlying cellular mechanisms remain largely unknown. Here, we demonstrate that otopetrins are critically involved in the calcification process by providing an exit route for protons liberated by the formation of CaCO(3). Using the sea urchin larva, we examined the otopetrin ortholog otop2l, which is exclusively expressed in the calcifying primary mesenchymal cells (PMCs) that generate the calcitic larval skeleton. otop2l expression is stimulated during skeletogenesis, and knockdown of otop2l impairs spicule formation. Intracellular pH measurements demonstrated Zn(2+)-sensitive H(+) fluxes in PMCs that regulate intracellular pH in a Na(+)/HCO(3)(−)-independent manner, while Otop2l knockdown reduced membrane proton permeability. Furthermore, Otop2l displays unique features, including strong activation by high extracellular pH (>8.0) and check-valve–like outwardly rectifying H(+) flux properties, making it into a cellular proton extrusion machine adapted to oceanic living conditions. Our results provide evidence that otopetrin family proton channels are a central component of the cellular pH regulatory machinery in biomineralizing cells. Their ubiquitous occurrence in calcifying systems across the animal kingdom suggest a conserved physiological function by mediating pH at the site of mineralization. This important role of otopetrin family proton channels has strong implications for our view on the cellular mechanisms of biomineralization and their response to changes in oceanic pH.

Purpose: Spicule has the ability to peel off the skin's surface layer and improve acne. Therefore, in this study, we suggest that the microdermabrasion effect of spicule cleanser improves pore keratinization of acne skin and inhibits the proliferation of skin bacteria (Propionibacterium acnes ) to improve acne lesion. Methods: There was no history of skin disease or allergy. Currently, 14 people were included in this study. Seven men and women were exposed to acne, pustules, pustules and nodules. We used the Korean Acne Grading System (KAGS) to evaluate acne and classify acne lesions every week. We conducted a questionnaire evaluation to evaluate the satisfaction and efficacy of clinical participants. The survey was analyzed using the analysis program of IBM SPSS 22.0. Results: The number of cysts, pustules and cysts decreased after 3 weeks in all 14 clinicians participating, and the acne grade improved significantly after 7 weeks. In particular, 78.5% of pores, 71.4% of acne and 95.7% of acne scars were improved. The longer the study period, the better the acne lesion was. Thus, it has been found that the microdermabrasion effect of a spicule cleanser improves the pore keratinization of acne skin and inhibits the proliferation of skin bacteria (Propionibacterium acnes ). Conclusion: As a result of KAGS analysis, the longer the treatment period, the better the acne lesion was. The spicule cleanser did not have a significant effect on gender or age. In addition, it was confirmed that it is effective for all four major diseases of acne: sebum secretion, pore keratinization, inflammation reaction, pustule and nodule.

Most sponges have biomineralized spicules. Molecular clocks indicate sponge classes diverged in the Cryogenian, but the oldest spicules are Cambrian in age. Therefore, sponges either evolved spiculogenesis long after their divergences or Precambrian spicules were not amenable to fossilization. The former hypothesis predicts independent origins of spicules among sponge classes and presence of transitional forms with weakly biomineralized spicules, but this prediction has not been tested using paleontological data. Here, we report an early Cambrian sponge that, like several other early Paleozoic sponges, had weakly biomineralized and hexactine-based siliceous spicules with large axial filaments and high organic proportions. This material, along with Ediacaran microfossils containing putative non-biomineralized axial filaments, suggests that Precambrian sponges may have had weakly biomineralized spicules or lacked them altogether, hence their poor record. This work provides a new search image for Precambrian sponge fossils, which are critical to resolving the origin of sponge spiculogenesis and biomineralization., Sponge animals likely originated in the Precambrian, but their early spicular fossils are ambiguous. Here, Tang et al. report a new Cambrian sponge taxon with weakly biomineralized spicules and suggest that the poor Precambrian record may reflect the later evolution of biomineralization.

Maldivea Gerlach, 1962 is a possible endemic genus of the Maldivian archipelago for which only M. xarifae Gerlach, 1962 has been described so far. A new species of this genus, M. complexa n.sp., was recently found in Felidhoo atoll. It reveals a more complex structure of gubernaculum than in type species which appears to be divided into two pieces: one is a sort of long wing in the ventral part of the spicule and the other one, more complex, is characterized by several curved stripes which envelop the dorsal side of the spicule distal part. According to the present considerations, diagnoses of Paroxystomininae and Maldivea are emended.

Ektaphelenchus koreanus n. sp. is isolated from Pinus packaging wood from Korea in Ningbo customs. The new species can be characterized by having four incisures in the lateral field, the excretory pore located posterior to nerve ring, female devoid of vulval flap, and having long post-vulval intestinal sac (55–106 μm), tail with a finely rounded terminus. Six caudal papillae in male and spicule short (12.7–13.7 μm), having broad squared to rounded condylus, triangular rounded rostrum, cucullus absent. Morphologically the species is most similar with E. berbericus, E. joyceae, E. oleae, E. ibericus, and E. taiwanensis but it can be differentiated by plenty of morphometrical and morphological characters. In addition, a morphometry table of Ektaphelenchus is also presented.

Summary Bursaphelenchus rockyi n. sp., isolated in Peking, China, from peat moss imported from Russia, is described. It is characterised by a lateral field with four lines, excretory pore located at the base of the nerve ring or slightly posterior, spicule 15.9 (15.1-17.3) μm long along the chord and with high condylus and a rounded tip, rostrum triangular or conical with bluntly pointed tip, lamina curvature becoming more pronounced at 60% of total length, six caudal papillae with P3 and P4 adjacent to each other, bursa small, starting posterior to P4, vulval lips hemispherical and protruding, and tail conical with finely rounded or mucronated terminus. The new species belongs to the fungivorus-group and is most similar to B. arthuri, B. arthuroides, B. fungivorus and B. seani, but can be distinguished from related species by morphological and sequencing results.

Dissolved silicon (DSi) is biologically processed to produce siliceous skeletons by a variety of organisms including radiolarians, silicoflagellates, choanoflagellates, plants, diatoms and some animals. In the photic ocean, diatoms are dominant consumers over competing other silicifiers. In Antarctica, where DSi is not particularly limiting, diatoms and sponges coexist in high abundances. Interestingly, diatom ingestion by sponges is a regular feeding strategy there. Although it was known that the diatom organic nutrients are readily metabolized by the sponges, what happened to the inorganic diatom silica skeleton remained unexplored. Here, we have conducted a multi-analytical approach to investigate the processing of diatom silica and whether it is reconverted into sponge silica. We have documented widespread diatom consumption by several demosponges, identifying storage vesicles for the diatom-derived silica by electron microscopy and microanalysis. Diatom-consuming sponges showed upregulation of silicatein and silicase genes, which in addition to the δ 30Si values of their silica, supports that the sponges are converting the ingested diatom silica into sponge silica without much further Si fractionation. Our multidisciplinary approach suggests that the reutilization of diatom silica by sponges is a common feature among Antarctic sponges, which should be further investigated in other latitudes and in other silicifiers.

International audience; Spicules are mineral-based biocomposites skeletal structures that are widely distributed among phylogenetically distant groups of invertebrates (Porifera, Cnidaria, Mollusca, Echinodermata). Subepidermal spicules are formed under the ectodermal epithelium and are characterized for all groups except mollusks (Aplacophora, Polyplacophora, Bivalvia), their spicules are located on the surface of the body. However, one group of mollusks (Gastropoda: Heterobranchia) have unique subepidermal spicules that have never been detected above the ectodermal epithelium and similarly to those characterized for Porifera, Cnidaria and Echinodermata. Understanding subepidermal spicule formation in mollusks could help solve the question on the origin of spicules. Spicules in nudibranchs have been described for more than 150 years, yet ontogenetic dynamics of spicules have never been studied and the full mechanism of their formation remains unknown. Herein we investigate the spicule formation in different stages of postlarval development of the nudibranch Onchidoris muricata (O.F. Müller, 1776). For the first time, ontogenetic transformations of the spicule complex are described using experiments and different morphological methods. Our studies demonstrate that spicules of O. muricata form in the subepidermal space in early developmental stages immediately after veliger settlement. A single spicule forms inside a huge vacuole within a sclerocyte and remains there throughout the entire life of the specimen. Signs of spicule or sclerocyte migration under the epithelium in postlarval development was not found. Spicules only form during larval settlement, increasing only in size as development furthers. For the first time, spicule mineralization zones were detected at the tips of the spicules as well as the presence of collagen I in the overall composition of the spicules. Thus, our findings suggest that spicules form by an ectodermal cell that emerged under the ectodermal epithelium during the earliest stages of postlarval development.

The spicules of male parasitic nematodes are key morphological features, which vary between species in shape and length and are used often for species identification. However, little is known about spicules and particularly if/how their length varies during growth. We first assessed the degree of variation in spicule length of maleHeligmosomoides bakeri21 days post infection (PI), and then in two follow-up experiments measured spicule lengths at half daily/daily intervals between days 6 and 14 PI. Mean spicule length in 21-day worms was 0.518 mm with a range of 94 μm, and variation between the two spicules of individual worms from 2 to 32 μm. Spicules were first detectable on day 6–6.5, after which their lengths increased until day 7 PI (mean = 0.61 and 0.59). This was followed by significant contraction, initially relatively quickly over the following 48 h and then more slowly over a longer period, stabilizing by days 10–14, with only minor further reduction in length. We conclude that the length of spicules varies significantly over the first few days after they have formed, and, consequently, the age of worms is an important factor for consideration when spicule lengths are measured for experimental/diagnostic or taxonomical purposes.

Background A basal spicule of the hexactinellid sponge Monorhaphis chuni may reach up to 3 m in length and 10 mm in diameter, an extreme case of large spicule size. Generally, sponge spicules are of scales from micrometers to centimeters. Due to its large size many researchers have described its structure and properties and have proposed it as a model of hexactinellid spicule development. Thorough examination of new material of this basal spicule has revealed numerous inconsistencies between our observations and earlier descriptions. In this work, we present the results of detailed examinations with transmitted light and epifluorescence microscopy, SEM, solid state NMR analysis, FTIR and X-ray analysis and staining of Monorhaphis chuni basal spicules of different sizes, collected from a number of deep sea locations, to better understand its structure and function. Results Three morphologically/structurally different silica layers i.e. plain glassy layer (PG), tuberculate layer (TL) and annular layer (AL), and an axial cylinder (AC) characterize adult spicules. Young, immature spicules display only plain glassy silica layers which dominate the spicule volume. All three layers i.e. PG, TL and AL can substitute for each other along the surface of the spicule, but equally they are superimposed in older parts of the spicules, with AL being the most external and occurring only in the lower part of the spicules and TL being intermediate between AL and PG. The TL, which is composed of several thinner layers, is formed by a progressive folding of its surface but its microstructure is the same as in the PG layer (glassy silica). The AL differs significantly from the PG and TL in being granular and porous in structure. The TL was found to display positive structures (tubercles), not depressions, as earlier suggested. The apparent perforated and non-perforated bands of the AL are an optical artefact. The new layer type that we called the Ripple Mark Layer (RML) was noted, as well as narrow spikes on the AL ridges, both structures not reported earlier. The interface of the TL and AL, where tubercles fit into depressions of the lower surface of the AL, represent tenon and mortise or dovetail joints, making the spicules more stiff/strong and thus less prone to breaking in the lower part. Early stages of the spicule growth are bidirectional, later growth is unidirectional toward the spicule apex. Growth in thickness proceeds by adding new layers. The spicules are composed of well condensed silica, but the outermost AL is characterized by slightly more condensed silica with less water than the rest. Organics permeating the silica are homogeneous and proteinaceous. The external organic net (most probably collagen) enveloping the basal spicule is a structural element that bounds the sponge body together with the spicule, rather than controlling tubercle formation. Growth of various layers may proceed simultaneously in different locations along the spicule and it is sclerosyncytium that controls formation of silica layers. The growth in spicule length is controlled by extension of the top of the axial filament that is not enclosed by silica and is not involved in further silica deposition. No structures that can be related to sclerocytes (as known in Demospongiae) in Monorhaphis were discovered during this study. Conclusions Our studies resulted in a new insight into the structure and growth of the basal Monorhaphis spicules that contradicts earlier results, and permitted us to propose a new model of this spicule’s formation. Due to its unique structure, associated with its function, the basal spicule of Monorhaphis chuni cannot serve as a general model of growth for all hexactinellid spicules.

Bramanti, Lorenzo ... et al.-- 12 pages, 4 figures, 3 tables, supporting information additional may be found in the online version of this article: http://onlinelibrary.wiley.com/doi/10.1111/gcb.12171/suppinfo, The mean predicted decrease of 0.3 to 0.4 pH units in the global surface ocean by the end of the century has prompted urgent research to assess the potential effects of ocean acidification on the marine environment, with strong emphasis on calcifying organisms. Among them, the Mediterranean red coral (Corallium rubrum) is expected to be particularly susceptible to acidification effects, due to the elevated solubility of its Mg-calcite skeleton. This, together with the large overexploitation of this species, depicts a bleak future for this organism over the next decades. In this study, we evaluated the effects of low pH on this species from aquaria experiments. Several colonies of C. rubrum were long-term maintained for 314 days in aquaria at two different pH levels (8.10 and 7.81, pHT). Calcification rate, spicule morphology, major biochemical constituents (protein, carbohydrates and lipids) and fatty acids composition were measured periodically. Exposure to lower pH conditions caused a significant decrease in the skeletal growth rate in comparison to the control treatment. Similarly, the spicule morphology clearly differed between both treatments at the end of the experiment, with aberrant shapes being observed only under the acidified conditions. On the other hand, while total organic matter was significantly higher under low pH conditions, no significant differences were detected between treatments regarding total carbohydrate, lipid, protein and fatty acid composition. However, the lower variability found among samples maintained in acidified conditions relative to controls, suggests a possible effect of pH decrease on the metabolism of the colonies. Our results show, for the first time, evidence of detrimental ocean acidification effects on this valuable and endangered coral specie, The research has been funded by the EC 7th FP (grant agreement 265103, Project MedSeA) and by the Spanish Ministry of Economy and Competitiveness (MINECO; CTM2009-08849, Project ACDC). The authors are grateful for the invaluable support of the Cap de Creus Marine Protected Area staff. [...] L.B. was supported by a Marie Curie IEF fellowship (EC7th FP, Project nº 221072), J.M. by a FPI studentship (BES-2007-16537), M.G. by of Erasmus Mundus scolarship (contract no. JEMES European UAB 2009/No.3) and S.R. by a Ramón y Cajal Contract (RyC-2007-01327) from MINECO. US National Science Foundation grant OCE 08-44785 provided support to L.B. during part of the writing of manuscript. This is a contribution from the Marine Biogeochemistry and Global Change research group, funded by Generalitat de Catalunya through grant 2009SGR142

Molluscs often possess complex calcified elements in addition to the shell, but how these elements function and relate to other tissues is often poorly understood. Dorid nudibranchs typically possess innumerable calcareous spicules arranged in complex networks. To describe how these spicules interact with muscles and connective tissue, we reconstructed tomographic digital models using serial sections and synchrotron micro-computed tomography. In two species with dramatically different spicule network morphologies, musculature was divided into a dorsal layer of crossed fibres, a ventral layer of branching radial fibres, and scattered dorsoventral fibres in between. These two species differed in the size of their dorsal tubercles, which was reflected in the organization of dorsal musculature, and in the amount and organization of connective tissue. InLes mollusques présentent fréquemment des éléments calcifiés complexes en plus de leur coquille, mais le fonctionnement de ces éléments et leur relation avec d’autres tissus ne sont souvent pas bien compris. Les nudibranches doridiens possèdent typiquement d’innombrables spicules calcaires disposés en réseaux complexes. Pour décrire l’interaction de ces spicules avec les muscles et les tissus conjonctifs, nous avons reconstitué des modèles numériques tomographiques en utilisant des séries de coupes et la microtomodensitométrie par synchrotron. Chez deux espèces dont les réseaux de spicules présentent des morphologies très différentes, la musculature est divisée en une couche dorsale de fibres entrecroisées, une couche ventrale de fibres radiales ramifiées et, entre les deux, des fibres dorsoventrales dispersées. Ces deux espèces diffèrent sur le plan de la taille de leurs tubercules dorsaux, ce qui se reflète dans l’organisation de la musculature dorsale, et de la quantité et de l’organisation du tissu conjonctif. Chez

A new nematode species,Latronema dyngisp. nov., is described from Skagerrak off the west coast of Sweden with the type locality near Dyngö island.Latronema dyngisp. nov. is characterized by multispiral amphideal fovea with circular outline, 0.2–0.3 corresponding body diameters wide in males and 0.1–0.2 corresponding body diameters wide in females, 12 cuticular longitudinal ridges and 18–27 precloacal supplements in males.Latronema dyngisp. nov. most closely resemblesL. orcinumin terms of body length; demanian ratios a, b, c and c′; number of amphid turns in males; and the ratio of spicule length to cloacal body diameter. The two species can be differentiated by the number longitudinal ridges on the cuticle (12 forLatronema dyngisp. nov. vs 20–22 forL. orcinum) and spicule length (65–78 μm forL. dyngivs 60 forL. orcinum) and shape (weakly arcuate forL. dyngisp. nov. vs strongly arcuate forL. orcinum). We also performed a maximum likelihood phylogenetic analysis on over 250 nematodes of the subclass Chromadoria based on their nearly full-length 18S rDNA sequences. In agreement with previous studies, our analysis supported Selachinematidae as a monophyletic group and placedRichtersiaSteiner, 1916 within Desmodoridae Filipjev, 1922 or just outside of the main Desmodorida clade with the latter placement not well supported.

Sea urchin larvae have an endoskeleton consisting of two calcitic spicules. The primary mesenchyme cells (PMCs) are the cells that are responsible for spicule formation. PMCs endocytose sea water from the larval internal body cavity into a network of vacuoles and vesicles, where calcium ions are concentrated until they precipitate in the form of amorphous calcium carbonate (ACC). The mineral is subsequently transferred to the syncytium, where the spicule forms. Using cryo-soft X-ray microscopy (cryo-SXM) we imaged intra-cellular calcium-containing particles in the PMCs and acquired Ca-L2,3X-ray absorption near edge spectra (XANES) of these Ca-particles. Using the pre-peak/main peak (L2’/ L2) intensity ratio, which reflects the atomic order in the first Ca coordination shell, we determined the state of the calcium ions in each particle. The concentration of Ca in each of the particles was also determined by the integrated area in the main Ca absorption peak. We observed about 700 Ca-particles with order parameters, L2’/ L2, ranging from solution to hydrated and anhydrous ACC, and with concentrations ranging between 1-15 M. We conclude that in each cell the calcium ions exist in a continuum of states. This implies that most, but not all water, is expelled from the particles. This cellular process of calcium concentration may represent a widespread pathway in mineralizing organisms.SignificanceOrganisms form mineralized skeletons, many of which are composed of calcium salts. Marine organisms extract calcium ions from sea water. One of the main unresolved issues is how organisms concentrate calcium by more than 3 orders of magnitude, to achieve mineral deposition in their skeleton. Here we determine the calcium state in each of the calcium-containing vesicles inside the spicule-building cells of sea urchin larvae. We show that within one cell there is a wide range of concentrations and states from solution to solid. We hypothesize that calcium concentration increases gradually in each vesicle, starting from sea water levels and until mineral is deposited. This model might well be relevant to other phyla, thus advancing the understanding of biomineralization processes.

We report that high-Mg calcite spherulites can undergo a coarsening process to form calcareous spicules of ∼30 microns in width and several hundred microns in length after an aging process in air for a prolonged period. During the aging process, the crystallinity of the calcitic structure has been improved substantially with a significant migration of Mg ions toward the mineral surface. In a thin-foil sample of the spicule aged for 20 months, nanocrystallites of magnesite with minor substitution level of Ca ions have been found near the surface of the spicule.

X-ray micro-computed tomography (micro-CT) is used to resolve the detailed internal architecture of the siliceous skeletons of two well-preserved middle Cambrian (Miaolingian Series) radiolarians from the Inca Formation of the Georgina Basin, Australia. Digital dissections of specimens of Archeoentactinia incaensis and A. tetractinia reveal for the first time that both are exclusively composed of tetractine spicules. A basal layer consisting of robust spicules together with an interwoven meshwork of smaller spicules is observed in both micro-CT models. Detailed structural analysis with the aid of a digitally inserted artificial sphere shows that the framework spicules are likely to have been added one by one as the radiolarian cell enlarged. The timing of spicule genesis may be an important factor controlling the morphology of different groups of spicular radiolarians. Observation of these fundamental skeletal structures suggests that the type genus of Archeoentactiniidae Archeoentactinia belongs to Echidninidae; thus, Archeoentactiniidae is a junior synonym of Echidninidae.

A new nematode species of the genusPhasmarhabditiswas isolated from the body surface of a slug (Philomycus bilineatusBenson, PB). Morphological and molecular analyses confirmed this nematode as a new species. The nematode was namedPhasmarhabditis zhejiangensissp. nov. (Nematoda: Rhabditidae) and is dioecious. In males, the open bursa with genital papillae is characterized by the formula 1-1-1-2-1-3, and the spicule length is 58μm. In female, the vulva is located approximately in the middle of the body. The nematode belongs to papillosa group because of its tail shape pointed with filiform tip. The phasmids are rod-shaped. The posterior anus is slightly swollen.P.zhejiangensiswas further characterized by internal transcribed spacer (ITS), 18S rDNA and 28S rDNA sequences. After the sequencing results were compared with sequences available from the National Center for Biotechnology Information (NCBI), the maximum similarities of ITS, 18S and 28S sequences were 89.81%, 96.22% and 95.28%, respectively. Phylogenetic analyses placedPhasmarhabditis zhejiangensissp. nov. in the genusPhasmarhabditis.

Summary Two isolates of Steinernema bertusi n. sp. were separately recovered from Tito, Mpumalanga, and Port Edward, Kwa Zulu Natal, South Africa. In this paper, we describe the isolates as a new entomopathogenic nematode (EPN) species using molecular and morphological methodologies. The new species belongs to the cameroonense-clade, which consists of nematodes only isolated from the African continent. Steinernema bertusi n. sp. is characterised by having the longest infective juvenile (IJ) for this clade at 716 (628-814) μm. The IJ is further characterised by a body diam. of 32 (28-36) μm and the pattern for the arrangement of the lateral ridges from head to tail is 2, 4, 5, 4, 2. The first-generation male spicule and gubernaculum length is 82 (72-88) μm and 63 (54-72) μm, respectively. Only 25% of the second-generation males possess a mucron. The first-generation females of S. bertusi n. sp. have a slightly protruding vulva, with double-flapped epiptygmata and a mucron at the posterior end. The new EPN species is most closely related to S. sacchari and is the sixth species to be included in the cameroonense-clade.

Alfv\'en waves are responsible for the transfer of magnetic energy in the magnetized plasma. They are involved in heating solar atmosphere and driving solar wind through various nonlinear processes. Since the magnetic field configurations directly affect the nonlinearity of Alfv\'en waves, it is important to investigate how they relate to the solar atmosphere and wind structure through the nonlinear propagation of Alfv\'en waves. In this study, we carried out the one-dimensional magnetohydrodynamic simulations to realize the above relation. The results show that when the nonlinearity of Alfv\'en waves in the chromosphere exceeds a critical value, the dynamics of the solar chromosphere (e.g., spicule) and the mass loss rate of solar wind tend to be independent of the energy input from the photosphere. In a situation where the Alfv\'en waves are highly nonlinear, the strong shear torsional flow generated in the chromosphere ``fractures'' the magnetic flux tube. This corresponds to the formation of chromospheric intermediate shocks, which limit the transmission of the Poynting flux into the corona by Alfv\'en waves and also inhibits the propagation of chromospheric slow shock., Comment: 25 pages, 22 figures, accepted for the publication in The Astrophysical Journal

Jet phenomena with a bright loop in their footpoint, called anemone jets, have been observed in the solar corona and chromosphere. These jets are formed as a consequence of magnetic reconnection, and from the scale universality of magnetohydrodynamics (MHD), it can be expected that anemone jets exist even in the solar photosphere. However, it is not necessarily apparent that jets can be generated as a result of magnetic reconnection in the photosphere, where the magnetic energy is not dominant. Furthermore, MHD waves generated from the photospheric jets could contribute to chromospheric heating and spicule formation; however, this hypothesis has not yet been thoroughly investigated. In this study, we perform 3D MHD simulation including gravity with the solar photospheric parameter to investigate anemone jets in the solar photosphere. In the simulation, jet-like structures were induced by magnetic reconnection in the solar photosphere. We determined that these jet-like structures were caused by slow shocks formed by the reconnection and were propagated approximately in the direction of the background magnetic field. We also suggested that MHD waves from the jet-like structures could influence local atmospheric heating and spicule formation., Comment: 34 pages, 21 figures, accepted for publication in PASJ

ObjectiveIt was hypothesized that the respective protein profiles of bovine cartilage from sites of localized mild to moderate (GI to GII) degeneration versus adjacent sites of intact tissue would vary in accordance with the tissue microstructural changes associated with a pre-osteoarthritic state.MethodsA total of 15 bovine patellae were obtained for this study. Paired samples of tissue were collected from the lateral region of each patella. If the patella contained a site of degeneration, a paired tissue set involved taking one sample each from the degenerated site and the intact tissue adjacent to it. Sufficient tissue was collected to facilitate 2 arms of investigation: microstructural imaging and proteome analysis. The microstructural analysis used a bespoke tissue preparation technique imaged with differential interference contrast optical microscopy to assess fibrillar scale destructuring and underlying bone spicule formation. An iTRAQ-based proteome analysis was performed using liquid chromatography–tandem mass spectrometry to identify the differential levels of proteins across the intact and degenerated cartilage and further, the results were validated with multiple reaction monitoring assay.ResultsIn the healthy cartilage pairs, there was no significant variation in protein profiles between 2 adjacent sample sites. In pairs of tissue that contained a sample of GI/GII tissue, there were both significant microstructural changes as well as the difference in abundance levels of 24 proteins.ConclusionsFrom the known functions of the 24 proteins, found to be strongly aligned with the specific microstructural changes observed, a unique “proteins ensemble” involved in the initiation and progression of early cartilage degeneration is proposed.

The study presents species composition and abundance of nematodes of the family Capillariidae (Nematoda, Trichocephalida), parasitizing the domestic goose (Anser anser dom. Linnaeus, 1758) in Poltava region, Ukraine. Morphological specifics of adult specimens of collected helminths are examined and new data is obtained for species identification of Capillariidae considering their metric parameters. The pathogens of capillariasis in geese are represented by two species, Baruscapillaria anseris (Madsen, 1945) Moravec, 1982 and B. obsignata (Madsen, 1945) Moravec, 1982 with the former predominant. Prevalence of infection by B. anseris in domestic fowl was up to 46.8%, the abundance index reached 17.9 specimens. The proportion of geese infected with B. obsignata was 23.9%, and the abundance index was 3.8 specimens. Morphological study of the collected mature male and female nematodes revealed the significant similarity of both species in the general body structure and in identification characters: vulva and vagina structure in females, tail end, spicule and spicule sheath in males. Statistically significant differences were determined in the metric parameters of male and female B. anseris and B. obsignata nematodes. Those differences can be used to improve species identification. Males of B. anseris were larger than males of B. obsignata by 16 metric parameters including the length and width of body, spicule and spicule sheath, width of pseudobursa, and distance between the rays of pseudobursa. Females of B. anseris and B. obsignata were significantly different by seven metric parameters. By five parameters (length and width of various body regions) the B. anseris females were larger than B. obsignata. Metric parameters of the studied species are also of interest for taxonomic identification: the eggs of B. obsignata are longer and narrower than those of B. anseris.

Aphelenchoides manipurensis sp. nov. was collected from two different localities of Manipur. Though the specimens collected from two different areas show some variations in their morphology and morphometric data, it was taken as the same species due to similarities in many characters. A. manipurensis sp. nov. had females with L = 294.1–461.91 µm, a = 24.28–38.14, b = 6.3–8.65, b′ = 3.61–4.68, c = 12.47–16.46, c′ = 3–4.25, stylet = 10.38–13.84 µm, V = 68.88–71.69, post uterine sac = 25.98–53.63 µm long and two lateral lines. Males were common with spicule of 10.38–17.3 µm. Mucro were present in both sexes. Species presented with illustrations and morphometrics.

Gracilacus paralatescens n. sp., isolated in Anji County, Zhejiang Province, China from the rhizospheric soil of bamboo. The new species can be characterized by the female lateral field with three incisures, stylet 71.5 to 78.8 µm long, lip region truncated, excretory pore located anterior to basal knobs. Vulval lips non-protruding and without vulval flap, spermatheca large, elongated squarish shaped filled with sperms. Tail slender, relatively straight having wedge shape terminus. The spicule slender, slightly curved and 17.5 to 18.9 µm long. In the phylogenetic analysis based on 18S, D2-D3 of 28S and ITS regions of rDNA, the new species is clustered with Paratylenchid species having longer stylet length. Morphologically, the new species belongs to Group 9 of Paratylenchus sensu lato and is most similar to G. latescens. Gracilacus paralatescens n. sp., isolated in Anji County, Zhejiang Province, China from the rhizospheric soil of bamboo. The new species can be characterized by the female lateral field with three incisures, stylet 71.5 to 78.8 µm long, lip region truncated, excretory pore located anterior to basal knobs. Vulval lips non-protruding and without vulval flap, spermatheca large, elongated squarish shaped filled with sperms. Tail slender, relatively straight having wedge shape terminus. The spicule slender, slightly curved and 17.5 to 18.9 µm long. In the phylogenetic analysis based on 18S, D2-D3 of 28S and ITS regions of rDNA, the new species is clustered with Paratylenchid species having longer stylet length. Morphologically, the new species belongs to Group 9 of Paratylenchus sensu lato and is most similar to G. latescens.