Sperm ultrastructure of an oviparous and an ovoviviparous onychophoran species (Peripatopsidae) with some phylogenetic considerations

The spermatozoa of the Australian oviparous Ooperipatellus insignis and the South African ovoviviparous Opisthopatus cinctipes (both: Onychophora, Peripatopsidae) were studied and compared with the spermatozoal patterns already described in the taxon. The spermatozoa of both species conform with the general plan described for the Onychophora: they are filiform cells formed, in sequence, by an elongated, fully condensed nucleus capped by an acrosome and surrounded by several spiral ridges; by a mitochondrial midpiece characteristically interpolated between the nucleus and a characteristic flagellum. Major differences between the spermatozoa of both species concern their acrosome organization. The correlation between the acrosomal pattern and the size and structure of the ovarial eggs (oocytes) in onychophorans has been investigated. A parsimony analysis was performed on 21 spermatozoal characters of the species considered. Its results are congruent with those of the traditional systematics. A new set of autapomorphies characterising onychophoran sperm is suggested and some of the spermatological homologies proposed between Onychophora and Euclitellata spermatozoa are critically discussed. Our analysis suggests that spermatozoal characters are good phylogenetic markers among onychophorans, also at low taxonomic level. Zusammenfassung Die Ultrastruktur der Spermien zweier Onychophoren-Arten (Peripatopsidae) wird vergleichend untersucht. Erstmals wird ein oviparer Vertreter berucksichtigt; namlich Ooperipatellus insignis vom Locus typicus; Mt. Macedon, Victoria, Australien. Seine Spermatozoen werden mit denen der ovoviviparen sudafrikanischen Art Opisthopatus cinctipes verglichen. Die Ergebnisse dieser Untersuchung werden mit verfugbaren Literaturdaten abgeglichen und ein Grundmuster fur Onychophoren-Spermien entwickelt. Die Spermien der beiden hier untersuchten Arten stimmen in ihrer Morphologie und Ultrastruktur im Wesentlichen mit dem bereits fur Onychophoren bekannten Muster uberein. Es sind fadige Zellen, die recht einheitlich aufgebaut sind. Sie weisen einen langlichen, kompakten Kern mit Akrosom-Kappe auf und sind spiralig von Furchen umgeben. Der mitochondriale Mittelbereich der Spermien liegt zwischen dem Nukleus und einem fur Onychophoren typischen Flagellum. Unterschiede betreffen dagegen die Organisation des Onychophoren-Akrosoms. Die mogliche Korrelation zwischen Akrosom-Ausbildung und Grose und Struktur der Ovarialeier wird untersucht. Basierend auf 21 Spermatozoen-Charakteren wird eine Parsimonie-Analyse durchgefuhrt. Die so gewonnenen Daten decken sich mit denjenigen der traditionellen Systematik. Die Spermien der Onychophoren weisen Merkmale auf, welche Autapomorphien des Taxon Onychophora sein konnen. Daruber hinaus werden mutmasliche Spermien-Homologien, die von verschiedenen Autoren fur die Taxa Onychophora und Euclitellata vorgeschlagen wurden, kritisch bewertet. Unsere Analyse zeigt, dass Spermien-Merkmale fur Onychophoren gute phylogenetische Marker darstellen, sogar auf Art-Niveau

Divergence of AMP Deaminase in the Ice Worm Mesenchytraeus solifugus (Annelida, Clitellata, Enchytraeidae)

Glacier ice worms, Mesenchytraeus solifugus and related species, are the largest glacially obligate metazoans. As one component of cold temperature adaptation, ice worms maintain atypically high energy levels in an apparent mechanism to offset cold temperature-induced lethargy and death. To explore this observation at a mechanistic level, we considered the putative contribution of 5′ adenosine monophosphate deaminase (AMPD), a key regulator of energy metabolism in eukaryotes. We cloned cDNAs encoding ice worm AMPD, generating a fragment encoding 543 amino acids that included a short N-terminal region and complete C-terminal catalytic domain. The predicted ice worm AMPD amino acid sequence displayed conservation with homologues from other mesophilic eukaryotes with notable exceptions. In particular, an ice worm-specific K188E substitution proximal to the AMP binding site likely alters the architecture of the active site and negatively affects the enzyme's activity. Paradoxically, this would contribute to elevated intracellular ATP levels, which appears to be a signature of cold adapted taxa

A general interpolation scheme for thermal fluctuations in superconductors

We present a general interpolation theory for the phenomenological effects of thermal fluctuations in superconductors. Fluctuations are described by a simple gauge invariant extension of the gaussian effective potential for the Ginzburg-Landau static model. The approach is shown to be a genuine variational method, and to be stationary for infinitesimal gauge variations around the Landau gauge. Correlation and penetration lengths are shown to depart from the mean field behaviour in a more or less wide range of temperature below the critical regime, depending on the class of material considered. The method is quite general and yields a very good interpolation of the experimental data for very different materials.Comment: some misprints have been corrected in Eq.(15),(19); more references and comments have been adde

Surgery-Guided Removal of Ovarian Cancer Using Up-Converting Nanoparticles

Ovarian cancer survival and the recurrence rate are drastically affected by the amount of tumor that can be surgically removed prior to chemotherapy. Surgeons are currently limited to visual inspection, making smaller tumors difficult to be removed surgically. Enhancing the surgeon’s ability to selectively remove cancerous tissue would have a positive effect on a patient’s prognosis. One approach to aid in surgical tumor removal involves using targeted fluorescent probes to selectively label cancerous tissue. To date, there has been a trade-off in balancing two requirements for the surgeon: the ability to see maximal tumors and the ability to identify these tumors by eye while performing the surgery. The ability to see maximal tumors has been prioritized and this has led to the use of fluorophores activated by near-infrared (NIR) light as NIR penetrates most deeply in this surgical setting, but the light emitted by traditional NIR fluorophores is invisible to the naked eye. This has necessitated the use of specialty detectors and monitors that the surgeon must consult while performing the surgery. In this study, we develop nanoparticles that selectively label ovarian tumors and are activated by NIR light but emit visible light. This potentially allows for maximal tumor observation and real-time detection by eye during surgery. We designed two generations of up-converting nanoparticles that emit green light when illuminated with NIR light. These particles specifically label ovarian tumors most likely via tumor-associated macrophages, which are prominent in the tumor microenvironment. Our results demonstrate that this approach is a viable means of visualizing tumors during surgery without the need for complicated, expensive, and bulky detection equipment. Continued improvement and experimentation could expand our approach into a much needed surgical technique to aid ovarian tumor removal

Effects of boron foliar sprays on tomato cultivation

Boron deficiency is very harmful in tomato (Solanum lycopersicum L.) cultivation. Boron foliar sprays can be used as a mean of preventing plant stunting, that results in low growth, poor onset of flowers and fruits, fruit physiological disorders, and hence, low tomato productivity. Boron sources and polyol like surfactants can affect foliar sprays' effectiveness. This work had the objective of evaluating foliar sprays of boric acid, borax and B-ethanolamine, with or without, polyol surfactant. The experiment was carried out in a 3×2+2 factorial arranged in randomized blocks with four replications. Plants of tomato cultivar 'Tangerine' F1 were fed with complete nutrient solution containing 5 μmol L-1 of B. These plants were sprayed with the three sources of boron, with or without a polyol like surfactant at 14 days intervals until the production cycle was complete. The additional treatments were: a positive control (C+), in which the plants received 20 μmol L-1 B, and a negative control (C-), in which the plants received 5 μmol L-1 B via nutrient solution, both without supply of B via foliar sprays. We evaluated plant height, root volume, number of flowers and fruits; dry matter production; nutrient contents and accumulation, in four phenological stages, and fresh and dry matter of fruits at the harvest. The data obtained were subjected to analysis of variance and the treatments compared by mean test. Leaf sprays improved the tomato growth and production compared to the (C-) treatment, but the adequate B supply by roots (C+) was the most efficient method for nutrition of tomato plants with boron. Among the boron sources, B-ethanolamine and boric acid were those which promoted the best results in tomato production, compared to the foliar application of borax. The use of the polyol like surfactant did not result in significant improvements on growth and production of the tomato plantsAuthors gratefully acknowledge the financial support by Spanish Ministry of Economy and Competitiveness project: AGL2013-44474-R and the Brazilian government agencies CAPES and CNP

[S,S]-EDDS/Fe: A new chelate for the environmentally sustainable correction of iron chlorosis in calcareous soil

Iron deficiency in crops is usually prevented and cured by the application of synthetic Fe chelates such as EDTA/Fe and the o,o-EDDHA/Fe. However their persistence in soil calls for the implementation of new alternatives that present less of a risk to the environment. This study therefore evaluated the biodegradable chelating agent [S,S]-EDDS as a new source for Fe fertilisation in calcareous soils in relation to its chemical reactivity. The suitability of [S,S]-EDDS/Fe as an Fe fertiliser in a calcareous soil was investigated and compared to the traditional synthetic chelates EDTA/Fe and o,o-EDDHA/Fe. Plant experiments with soybean (Glycine max), 57Fe isotopic labelling, and batch incubations were conducted in a calcareous soil. The Fe concentration of plants treated with [S,S]-EDDS/Fe was similar to those treated with EDTA/Fe. A similar Fe concentration to the o,o-EDDHA/Fe treatment was achieved using a double dose of [S,S]-EDDS/Fe. Despite the degradation of [S,S]-EDDS limiting the durability of [S,S]-EDDS/Fe in soil, the Fe bound to the degradation products may be a determining factor in improving Fe uptake and translocation to leaves in plants treated with [S,S]-EDDS/Fe compared to other Fe sources. Speciation studies by modelling and batch experiments also supported the lower reactivity of [S,S]-EDDS/Fe with calcium compared to that of EDTA/Fe, possibly contributing to the permanence of [S,S]-EDDS/Fe in the calcareous soil. This study demonstrated for the first time, that [S,S]-EDDS may be an environmentally sustainable alternative to traditional synthetic chelating agents such as EDTA or o,o-EDDHA for curing Fe chlorosis in susceptible plants in calcareous soilThis work was supported by the Spanish MINECO Project AGL2013-44474-R from the Ministerio Economía y Competitivida

A Double-Blind, RCT Testing Beneficial Modulation of BDNF in Middle-Aged, Life Style-Stressed Subjects: A Clue to Brain Protection?

Introduction: The aim of this prospective study was to see whether LD-1227, a quality-controlled marine nutraceuticals shown to protect experimental stress-induced hyppocampal degeneration, could beneficially modulate BDNF, as measured in the serum, in otherwise healthy but work-stressed individuals. Materials and Methods: Forty-eight men and women between the ages of 38 and 62 reporting high-demanding work activity but with an overall positive attitude towards their personal life were recruited. Subjects were divided in two group (24 patients each) and blindly supplemented for 2 month with: a) LD-1227 400mg or b) placebo. A third group of healthy non-stressed subjects was used as well. Blood samples were taken before and after the supplementation period. Unstimulated saliva was collected and tested for amylase while serum levels were used to measure BDNF. State Trait Anxiety Inventory (STAI), Pittsburgh Sleep Quality Index (PSQI) and psychological wellbeing assessment (PSWB) were measured too. Patients with Val66Met functional polymorphism of BDNF excluded those given their reported association with an impaired release of BDNF. Results: Results showed that, as compared to healthy, nonstressed individuals, stressed ones has a trend decrease of BDNF and this was significantly increased by LD 12-1227 supplementation and the same inverse phenomenon occurred to salivary amylase (p<0.05). No change was noted in the PSQI score but, either STAI or PSWB tests scored better in LD-1227 supplemented subjects. Conclusion: The present data suggest that LD-1227 is beneficially affecting neuromodulation and related symptoms during common stressful life conditions and may have the potential as tools in a neuroprotective clinical strategy

International Delegations and the Values of Federalism

Inland water sediments receive large quantities of terrestrial organic matter(1-5) and are globally important sites for organic carbon preservation(5,6). Sediment organic matter mineralization is positively related to temperature across a wide range of high-latitude ecosystems(6-10), but the situation in the tropics remains unclear. Here we assessed temperature effects on the biological production of CO2 and CH4 in anaerobic sediments of tropical lakes in the Amazon and boreal lakes in Sweden. On the basis of conservative regional warming projections until 2100 (ref. 11), we estimate that sediment CO2 and CH4 production will increase 9-61% above present rates. Combining the CO2 and CH4 as CO2 equivalents (CO(2)eq; ref. 11), the predicted increase is 2.4-4.5 times higher in tropical than boreal sediments. Although the estimated lake area in low latitudes is 3.2 times smaller than that of the boreal zone, we estimate that the increase in gas production from tropical lake sediments would be on average 2.4 times higher for CO2 and 2.8 times higher for CH4. The exponential temperature response of organic matter mineralization, coupled with higher increases in the proportion of CH4 relative to CO2 on warming, suggests that the production of greenhouse gases in tropical sediments will increase substantially. This represents a potential large-scale positive feedback to climate change

Photogeneration of α‑Bimetalloid Radicals via Selective Activation of Multifunctional C1 Units

Light-driven strategies that enable the chemoselective activation of a specific bond in multifunctional systems are comparatively underexplored in comparison to transition-metal-based technologies, yet desirable when considering the controlled exploration of chemical space. With the current drive to discover next-generation therapeutics, reaction design that enables the strategic incorporation of an sp 3 carbon center, containing multiple synthetic handles for the subsequent exploration of chemical space would be highly enabling. Here, we describe the photoactivation of ambiphilic C1 units to generate α-bimetalloid radicals using only a Lewis base and light source to directly activate the C–I bond. Interception of these transient radicals with various SOMOphiles enables the rapid synthesis of organic scaffolds containing synthetic handles (B, Si, and Ge) for subsequent orthogonal activation. In-depth theoretical and mechanistic studies reveal the prominent role of 2,6-lutidine in forming a photoactive charge transfer complex and in stabilizing in situ generated iodine radicals, as well as the influential role of the boron p-orbital in the activation/weakening of the C–I bond. This simple and efficient methodology enabled expedient access to functionalized 3D frameworks that can be further derivatized using available technologies for C–B and C–Si bond activation