Silaffins of Diatoms: From Applied Biotechnology to Biomedicine

Silaffins are involved in the formation of the cell walls of diatoms. It is known that silaffins can precipitate silica in vitro, forming nano- and micro-particles in the shape of spheres and plates containing many pores. It is important to note that the deposition of silica and the particle morphology in the presence of silaffins affects chemical and physical agents (e.g., peptides, polyamines, phosphate, nitrogen, and the mechanical changes of the reaction mixture). It is believed that silaffins act as an organic matrix for silica-genesis and that silica pore size should reflect the pattern of a matrix. Here, biotechnology related to silaffins is discussed in the context of “a hypothesis of silaffin matrix” and “the LCPA-phosphate model”. We discuss the most promising area of silaffin biotechnology—the development of production methods for silicon structures with desired shapes and nanostructural properties that can be used to create biocompatible materials.     

Anti-Inflammatory and Analgesic Effects of TRPV1 Polypeptide Modulator APHC3 in Models of Osteo- and Rheumatoid Arthritis

Arthritis is a widespread inflammatory disease associated with progressive articular surface degradation, ongoing pain, and hyperalgesia causing the development of functional limitations and disability. TRPV1 channel is one of the high-potential targets for the treatment of inflammatory diseases. Polypeptide APHC3 from sea anemone Heteractis crispa is a mode-selective TRPV1 antagonist that causes mild hypothermia and shows significant anti-inflammatory and analgesic activity in different models of pain. We evaluated the anti-inflammatory properties of APHC3 in models of monosodium iodoacetate (MIA)-induced osteoarthritis and complete Freund’s adjuvant (CFA)-induced rheumatoid monoarthritis in comparison with commonly used non-steroidal anti-inflammatory drugs (NSAIDs) such as diclofenac, ibuprofen, and meloxicam. Subcutaneous administration of APHC3 (0.1 mg/kg) significantly reversed joint swelling, disability, grip strength impairment, and thermal and mechanical hypersensitivity. The effect of APHC3 was equal to or better than that of reference NSAIDs. Protracted treatment with APHC3 decreased IL-1b concentration in synovial fluid, reduced inflammatory changes in joints, and prevented the progression of cartilage degradation. Therefore, polypeptide APHC3 has the potential to be an analgesic and anti-inflammatory substance for the alleviation of arthritis symptoms.     

Identification of key climatic factors regulating the transport of pesticides in leaching and to tile drains

BACKGROUND: Key climatic factors influencing the transport of pesticides to drains and to depth were identified. Climatic characteristics such as the timing of rainfall in relation to pesticide application may be more critical than average annual temperature and rainfall. The fate of three pesticides was simulated in nine contrasting soil types for two seasons, five application dates and six synthetic weather data series using the MACRO model, and predicted cumulative pesticide loads were analysed using statistical methods. RESULTS: Classification trees and Pearson correlations indicated that simulated losses in excess of 75th percentile values (0.046 mg m(-2) for leaching, 0.042 mg m(-2) for drainage) generally occurred with large rainfall events following autumn application on clay soils, for both leaching and drainage scenarios. The amount and timing of winter rainfall were important factors, whatever the application period, and these interacted strongly with soil texture and pesticide mobility and persistence. Winter rainfall primarily influenced losses of less mobile and more persistent compounds, while short-term rainfall and temperature controlled leaching of the more mobile pesticides. CONCLUSIONS: Numerous climatic characteristics influenced pesticide loss, including the amount of precipitation as well as the timing of rainfall and extreme events in relation to application date. Information regarding the relative influence of the climatic characteristics evaluated here can support the development of a climatic zonation for European-scale risk assessment for pesticide fate.     

A refined lack‐of‐fit statistic to calibrate pesticide fate models for responsive systems

BACKGROUND: Calibration by inverse modelling was performed with the MACRO transport and fate model using long‐term (>10 years) drainflow and isoproturon (IPU) data from western France. Two lack‐of‐fit (LOF) indices were used to control the inverse modelling: sum of squares (SS) and an alternative statistic called the vertical‐horizontal distance integrator (VHDI), which is designed to account for offsets in observed and predicted arrival times of peak IPU concentration. With these data, SS was artificially inflated because it is limited to comparison of predicted and observed IPU concentrations that are concurrent in time. The LOFs were used along with the index of agreement (d) and the correlation coefficient (r) to ascertain the fit of the calibrated models. RESULTS: Predicted arrival times of peak IPU concentration differed somewhat from observed times. All four indices indicated better model fit for the second of two validation periods when inverse modelling was controlled by VHDI rather than SS (SS = 26.4, d = 0.660, r = 0.606 and VHDI = 1.25). The VHDI statistic was markedly lower compared with the uncalibrated model (38.0) and SS calibration results (24.5). The final maximum predicted IPU concentration (44.5 µg L^?1) for the calibration period was very similar to the observed value (44 µg L^?1). CONCLUSION: VHDI is seen as an effective alternative to SS for calibration and validation of pesticide fate models applied to responsive systems. VHDI provided a more realistic assessment of model performance for the transient flows and short‐lived concentrations observed here, and also effectively substituted for the objective function in inverse modelling. Copyright © 2009 Society of Chemical Industry     

Intake,digestibility, performance,and carcass traits of beef cattle of different gender

The performance, intake, feed efficiency, and carcass traits of beef cattle from different gender profile were assessed. Fifteen animals (five steers, five spayed heifers, and five intact heifers) with ±250 kg of initial body weight were randomly assigned in individual pens and fed the same diet for 106 days. At the end of the trial, all the animals were slaughtered and the pH, temperature, and weight of the carcass were recorded. The right side of each carcass was then separated into chuck, shoulder, flank sirloin, and round for evaluation of commercial cuts yield. The left carcass sides were ribbed between the 12th and 13th ribs where the rib eye area and fat thickness measurements were taken. The 9th–11th rib section was removed from the left half carcass and then dissected into muscle, fat, and bones in order to estimate carcass composition. Gender had no effect (P > 0.05) on performance, intake, digestibility of dry matter and all the nutrients evaluated, feed efficiency, and carcass characteristics. It can be concluded that steers and heifers (spayed or not) have the same potential to produce beef. From a productive and welfare standpoint, there is no reason to spay heifers.     

Synthetic Zeolite A as Zinc and Manganese Fertilizer in Calcareous Soil

The Leccino olive cultivar was grown in pots contained calcareous rendzina soil amended with NPK fertilizer (control treatment) or with further addition of Zeolite A (ZA) containing either zinc (Zn²⁺) or manganese (Mn²⁺) (Zn-ZA and Mn-ZA). After one year, vegetative growth and root morphological parameters were measured and elemental analysis was performed on the root, stem, and leaves. Compared to other treatments, the Zn-ZA fertilizer enhanced Zn concentration and total quantity in the root, stem, and leaves, as well as the root diameter. The root volume was greater using Zn-ZA treatment than control treatment. The total quantity of Mn in root and the root length were enhanced when using Mn-ZA compared to control or Zn-ZA treatment. According to the results of this study, it appears that zeolites containing Zn provide favorable conditions for Zn uptake in calcareous soils, while both Zn and Mn zeolites have a positive impact on olive root morphology.     

Erratum to: Chemical contamination in upper horizon of Haplic Chernozem as a transformation factor of its physicochemical properties

Journal of Soils and Sediments -     

Analysis of population structure and genetic diversity reveals gene flow and geographic patterns in cultivated rice (<Emphasis Type="Italic">O. sativa</Emphasis> and <Emphasis Type="Italic">O. glaberrima</Emphasis>) in West Africa

To fully exploit the diversity in African rice germplasm and to broaden the gene pool reliable information on the population genetic diversity and phenotypic characteristics is a prerequisite. In this paper, the population structure and genetic diversity of 42 cultivated African rice (Oryza spp.) accessions originating from West Africa (Benin, Mali and Nigeria, Liberia etc.) were investigated using 20 simple sequence repeats (SSR) and 77 amplified fragment length polymorphisms (AFLP). Additionally, field trials were set up to gain insight into phenotypic characteristics that differentiate the genetic populations among rice accessions. The analysis revealed considerably high polymorphisms for SSR markers (PIC mean?=?0.78) in the germplasm studied. A significant association was found between AFLP markers and geographic origin of rice accessions (R?=?0.72). Germplasm structure showed that Oryza sativa accessions were not totally isolated from Oryza glaberrima accessions. The results allowed identification of five O. glaberrima accessions which grouped together with O. sativa accessions, sharing common alleles of 18 loci out of the 20 SSR markers analyzed. Population structure analysis revealed existence of a gene flow between O. sativa and O. glaberrima rice accessions which can be used to combine several interesting traits in breeding programs. Further studies are needed to clarify the contributions of this gene flow to valuable traits such as abiotic and biotic stresses including disease resistance.     

6-Bromohypaphorine from Marine Nudibranch Mollusk Hermissenda crassicornis is an Agonist of Human α7 Nicotinic Acetylcholine Receptor

6-Bromohypaphorine (6-BHP) has been isolated from the marine sponges Pachymatisma johnstoni, Aplysina sp., and the tunicate Aplidium conicum, but data on its biological activity were not available. For the nudibranch mollusk Hermissenda crassicornis no endogenous compounds were known, and here we describe the isolation of 6-BHP from this mollusk and its effects on different nicotinic acetylcholine receptors (nAChR). Two-electrode voltage-clamp experiments on the chimeric α7 nAChR (built of chicken α7 ligand-binding and glycine receptor transmembrane domains) or on rat α4β2 nAChR expressed in Xenopus oocytes revealed no action of 6-BHP. However, in radioligand analysis, 6-BHP competed with radioiodinated α-bungarotoxin for binding to human α7 nAChR expressed in GH₄C₁ cells (IC₅₀ 23 ± 1 μM), but showed no competition on muscle-type nAChR from Torpedo californica. In Ca²⁺-imaging experiments on the human α7 nAChR expressed in the Neuro2a cells, 6-BHP in the presence of PNU120596 behaved as an agonist (EC₅₀ ~80 μM). To the best of our knowledge, 6-BHP is the first low-molecular weight compound from marine source which is an agonist of the nAChR subtype. This may have physiological importance because H. crassicornis, with its simple and tractable nervous system, is a convenient model system for studying the learning and memory processes.     

Post‐capture survival of whale sharks encircled in tuna purse‐seine nets: tagging and safe release methods

1. Whale shark, the world's largest fish, is believed to be particularly vulnerable owing to its biological characteristics (slow growth, late maturation, great longevity) and is listed as Vulnerable by IUCN and included in Appendix II of CITES. 2. Whale sharks are occasionally encircled in tropical tuna purse‐seine nets, throughout this global fishery. Although apparent immediate survival rates following encirclement and release have recently been assessed through scientific onboard observer programmes, a more rigorous methodology is still required for studying post‐released survival. 3. This work provides a method for applying pop‐up satellite tags and reports an enhanced release procedure for whale sharks. The first assessment of survival after release from purse‐seine nets involved six whale sharks tagged between May and September 2014 in the eastern tropical Atlantic Ocean. Five tags transmitted data: three popped up as programmed (after 30 days), while two surfaced prematurely (one after 21 and the other after 71 days (programmed to pop off after 30 and 90 days, respectively)) but showed no sign of unusual behaviour. 4. Overall, whale sharks survived at least 21 days (one at least 71 days) after release from purse‐seine nets. These observations based on five large individuals (total length > 8 m), suggest that whale sharks have a good chance of survival when released with the proposed method. 5. Additional tagging in this and other oceans, especially of juveniles which may be more sensitive to encirclement and release operations, is essential to further assess whale shark post‐release survival rates in tuna purse‐seine fisheries. Copyright © 2016 John Wiley & Sons, Ltd.