The effects of clodronate on increased bone turnover and bone loss due to ovariectomy in rats

The present study was carried out to investigate the ability of clodronate to inhibit ovariectomy-induced bone loss and increased bone turnover in rats. Estradiol was administered as a reference compound. Seventy Sprague-Dawley rats were ovariectomized (OVX) or sham-operated (Sham) at the age of 90 days and divided into seven groups. Two Sham and two OVX groups received subcutaneously either the vehicle of clodronate or the vehicle of estradiol. Other OVX groups were given s.c. either disodium clodronate at two dose levels (5 mg/kg or 12.5 mg/kg twice a week) or 17 beta-estradiol (10 micrograms/kg five times a week) for 8 weeks. Femur length, volume, dry weight, and ash weight were determined, and proximal ends of tibiae were used for bone histomorphometry. Markers of bone metabolism were measured from urine and serum. A significant loss of 54% of trabecular bone area of proximal tibial metaphysis was found at 8 weeks after ovariectomy. Clodronate and estradiol inhibited (p < 0.001) this osteopenia. Both drugs prevented the decrease in ash weight/volume of the femur. The inhibitory effect of clodronate and estradiol on bone resorption in OVX rats could be detected also in decreased urinary excretion of hydroxyproline and lysylpyridinoline (p < 0.001). Clodronate and estradiol decreased (p < 0.001) the ovariectomy-induced enhanced tibial endocortical mineral apposition rate (Ec.MAR) on the lateral cortex to the level of the Sham group. In contrast, periosteal MAR analyzed on the medial side of tibial cortical bone did not change significantly in the OVX/Veh group. Estradiol decreased periosteal MAR to below the level in the Sham group (p < 0.01). These results suggest that ovariectomy of growing rats resulted in tibial and femoral osteopenia two months later. Clodronate as well as estradiol can suppress bone resorption and turnover in ovariectomized rats, inhibiting the development of osteopenia. Both clodronate doses (5 and 12.5 mg/kg) had beneficial effects in ovariectomized animals.     

Fluidized Bed Device for Plastic Granules Triboelectrification

The study of the triboelectrification process is the key factor to the successful industrial application of electrostatic separation in the field of plastics recycling. Therefore, the aim of the present work is to evaluate an original device for the laboratory study of this process. The original design of the fluidized bed type triboelectrification device has the following distinctive features: (i) transparent walls to observe the fluidization process and the particles moving in the triboelectrification module; (ii) air distributors with different mesh apertures correlated with granule size; (iii) quick replacement of the triboelectrification Plexiglas chamber with other metallic (aluminium, copper) or nonmetallic chambers (polyvinyl chloride—PVC, polyethylene—PE, and polyethylene terephthalate—PET); (iv) possibility of independent operation, for granule charge measurement or integrated operation, for the electrostatic separation experiments using a free-fall electrostatic separator. The results of charge measurement experiments pointed out the different triboelectric behaviour of two types of granules (polystyrene and low-density polyethylene) in contact with the walls of the device. The electrostatic separation experiments carried out on a binary mixture of mm-size polystyrene/polyethylene granules confirmed the effectiveness of the triboelectrification device.     

Fluidized Bed Device for Plastic Granules Triboelectrification

The study of the triboelectrification process is the key factor to the successful industrial application of electrostatic separation in the field of plastics recycling. Therefore, the aim of the present work is to evaluate an original device for the laboratory study of this process. The original design of the fluidized bed type triboelectrification device has the following distinctive features: (i) transparent walls to observe the fluidization process and the particles moving in the triboelectrification module; (ii) air distributors with different mesh apertures correlated with granule size; (iii) quick replacement of the triboelectrification Plexiglas chamber with other metallic (aluminium, copper) or nonmetallic chambers (polyvinyl chloride—PVC, polyethylene—PE, and polyethylene terephthalate—PET); (iv) possibility of independent operation, for granule charge measurement or integrated operation, for the electrostatic separation experiments using a free-fall electrostatic separator. The results of charge measurement experiments pointed out the different triboelectric behaviour of two types of granules (polystyrene and low-density polyethylene) in contact with the walls of the device. The electrostatic separation experiments carried out on a binary mixture of mm-size polystyrene/polyethylene granules confirmed the effectiveness of the triboelectrification device.     

Rodlet cells development in the intestine of sea bass (Dicentrarchus labrax)

The enigmatic rodlet cells (RCs) are characterized by conspicuous inclusions named “rodlets”. They were discovered over 100 years ago and were considered as parasites but shortly afterward interpreted as endogenous cells. The RCs have been described in different tissues of marine and freshwater teleosts, but their origin and function remain unknown. This work was designed to an ultrastructural study on RCs development and distribution in intestinal epithelium of Dicentrarchus labrax. Three different stages of RCs development from early precursor cells to mature phase were observed, as well as a migration and finally an extrusion of their contents. In this study, the immature cells were found near the basal epithelium membrane. They were mainly identified by a rough endoplasmic reticulum with dilated cisternae, by developing rodlets and a thin fibrillar coat. The maturing RCs, localized in the middle zone of the epithelium, appeared to be undergoing a reorganization of the cell organelles. The mature RCs, placed near the free surface, showed a thick subplasmalemmar fibrillar coat. Most of the organelles were aggregated at the cell apex with a basally located nucleus. A cellular polarity was more evident. One of the most conspicuous features was the occurrence of mature rodlets club‐sac in shape orientated toward the cell apex. Adhesive junctions between surface epithelial cells and RCs, while discharging their contents, were seen. We have connected morphological figures and distribution to different stages of development in RCs, supporting the hypothesis of their secretory function. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.     

Decision tree models for profiling ski resorts’ promotional and advertising strategies and the impact on sales

Based on survey data, this paper builds decision tree models to profile the online and mobile technologies and services that ski resorts use for their promotional and advertising strategies for two important segments, namely millennials (less than and equal to 35) and non-millennials (greater than 35). The technologies and services include resort websites, microblogging services, and online coupon services. The decision tree models reveal that ski resorts use specific strategies for these segments. Also, the paper reveals the impact that the technologies and services have on resort sales. The impact is positive and both immediate and sustained in nature. The research is the first of its type in the ski industry and represents a novel use of decision tree models for profiling promotional and advertising strategies.     

Age-related changes in the avian primary lymphoid organs (thymus and bursa of Fabricius)

The avian primary lymphoid organs, the thymus and the bursa of Fabricius, undergo age-dependent changes leading in some cases to the complete atrophy of the organ. Nevertheless, the timetable of the involutive process as well as the consequences in the structure and functionality of the organs vary largely in the time frame and structural changes among species. On the other hand, and in contrast with the large body of literature reporting the structural and functional changes in mammalian primary lymphoid organs, the age-dependent changes in avian thymus and bursa of Fabricius are scarce, fragmentary, and heterogeneous. This article reviews the current literature on this topic, and focuses primarily on the involution of the bursa of Fabricius.     

A missense mutation in PFAS (phosphoribosylformylglycinamidine synthase) is likely causal for embryonic lethality associated with the MH1 haplotype in Montbéliarde dairy cattle

A candidate mutation in the sex hormone binding globulin gene was proposed in 2013 to be responsible for the MH1 recessive embryonic lethal locus segregating in the Montbéliarde breed. In this follow-up study, we excluded this candidate variant because healthy homozygous carriers were observed in large-scale genotyping data generated in the framework of the genomic selection program. We fine mapped the MH1 locus in a 702-kb interval and analyzed genome sequence data from the 1,000 bull genomes project and 54 Montbéliarde bulls (including 14 carriers and 40 noncarriers). We report the identification of a strong candidate mutation in the gene encoding phosphoribosylformylglycinamidine synthase (PFAS), a protein involved in de novo purine synthesis. This mutation, located in a class I glutamine amidotransferase–like domain, results in the substitution of an arginine residue that is entirely conserved among eukaryotes by a cysteine (p.R1205C). No homozygote for the cysteine-encoding allele was observed in a large population of more than 25,000 individuals despite a 6.7% allelic frequency and 122 expected homozygotes under neutrality assumption. Genotyping of 18 embryos collected from heterozygous parents as well as analysis on nonreturn rates suggested that most homozygous carriers died between 7 and 35 d postinsemination. The identification of this strong candidate mutation will enable the accurate testing of the reproducers and the efficient selection against this lethal recessive embryonic defect in the Montbéliarde breed.     

Invited review: Enteric methane in dairy cattle production: Quantifying the opportunities and impact of reducing emissions

Many opportunities exist to reduce enteric methane (CH₄) and other greenhouse gas (GHG) emissions per unit of product from ruminant livestock. Research over the past century in genetics, animal health, microbiology, nutrition, and physiology has led to improvements in dairy production where intensively managed farms have GHG emissions as low as 1 kg of CO₂ equivalents (CO₂e)/kg of energy-corrected milk (ECM), compared with >7 kg of CO₂e/kg of ECM in extensive systems. The objectives of this review are to evaluate options that have been demonstrated to mitigate enteric CH₄ emissions per unit of ECM (CH₄/ECM) from dairy cattle on a quantitative basis and in a sustained manner and to integrate approaches in genetics, feeding and nutrition, physiology, and health to emphasize why herd productivity, not individual animal productivity, is important to environmental sustainability. A nutrition model based on carbohydrate digestion was used to evaluate the effect of feeding and nutrition strategies on CH₄/ECM, and a meta-analysis was conducted to quantify the effects of lipid supplementation on CH₄/ECM. A second model combining herd structure dynamics and production level was used to estimate the effect of genetic and management strategies that increase milk yield and reduce culling on CH₄/ECM. Some of these approaches discussed require further research, but many could be implemented now. Past efforts in CH₄ mitigation have largely focused on identifying and evaluating CH₄ mitigation approaches based on nutrition, feeding, and modifications of rumen function. Nutrition and feeding approaches may be able to reduce CH₄/ECM by 2.5 to 15%, whereas rumen modifiers have had very little success in terms of sustained CH₄ reductions without compromising milk production. More significant reductions of 15 to 30% CH₄/ECM can be achieved by combinations of genetic and management approaches, including improvements in heat abatement, disease and fertility management, performance-enhancing technologies, and facility design to increase feed efficiency and life-time productivity of individual animals and herds. Many of the approaches discussed are only partially additive, and all approaches to reducing enteric CH₄ emissions should consider the economic impacts on farm profitability and the relationships between enteric CH₄ and other GHG.