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This initial genome-wide analysis of epigenetic markings in the sperm of infertile men demonstrates differences in composition and epigenetic markings compared with fertile men, especially at certain imprinted and developmental loci. Although no single locus displays a complete change in chromatin packaging or DNA modification, the data suggest that moderate changes throughout the genome exist and may have a cumulative detrimental effect on fecundity.

Additive manufacturing (AM), where a part is built layer-by-layer, is a promising approach for creating near-net shapes and is challenging the dominance of conventional manufacturing processes for products with high complexity and greater material efficiency 1 . However, achieving good mechanical properties in the as-produced part, given the variation in solidification conditions including the control of defects in AM, is challenging. In particular there are limited opportunities for post processing to further control the microstructure/properties. Therefore, further metallurgical research on materials for AM is required to accelerate the maturity of AM technology for structural components. 3D-printed titanium alloys have been used in numerous applications, including the biomedical and aerospace industries. However, the 3D-printing of many conventional titanium alloys usually results in a microstructure comprised of coarse columnar grains, which often leads to undesirable anisotropic mechanical properties. In contrast to other common engineering alloys, such as aluminium, there is no commercial grain refiner, containing potent inoculants that can survive in liquid Ti, able to control microstructure effectively. To address this challenge, we have developed a novel technique for AM by using Ti-Cu alloys with a high constitutional supercooling capacity that overrides the negative effect of a high thermal gradient in the melt pool during AM. Through this approach, it is shown that an as-printed Ti-Cu alloy specimen is comprised of fully equiaxed, fine grained microstructure without any special process control or additional subsequent treatment. The new AM Ti-Cu alloys also display promising mechanical properties, compared to conventional alloys under similar processing conditions, due to the formation of an ultrafine eutectoid microstructure by taking full advantage of the high cooling rates and multiple thermal cycles in the AM process. We anticipate that this approach will be equally applicable to other eutectoid forming alloy systems. MainMetal based 3D printing or additive manufacturing (AM) is enabling mass customization of manufactured parts. The intrinsic high cooling rates and high thermal gradient in the metal AM process often leads to a very fine microstructure and a tendency towards almost exclusively columnar grains particularly in Ti-based alloys 1 . Such columnar grains in AM Ti components can cause anisotropic mechanical properties and hence are not desirable 2 . Numerous attempts to optimise the processing parameters of AM have shown that it is extremely difficult to alter the conditions such that equiaxed growth of prior β-Ti grains is promoted 3 . According to the Interdependence Theory 4 , the key factors controlling grain Affiliations

Monoclonal antibodies to fibrillin 1 (MP340), a component of elastin-associated microfibrils, were used to screen cDNA libraries made from bovine nuchal ligament mRNA. One of the selected clones (cL9; 1.2 kb) hybridized on Northern (RNA) blotting with nuchal ligament mRNA to two abundant mRNAs of 9.0 and 7.5 kb, which were clearly distinct from fibrillin mRNA (10 kb). Further library screening and later reverse transcription PCR by the rapid amplification of cDNA ends (RACE) technique resulted in the isolation of additional overlapping cDNAs corresponding to about 6.7 kb of the mRNA. The encoded protein exhibited sequence similarity of around 80% with a recently identified human protein named latent transforming growth factor ␤1 (TGF-␤1)-binding protein 2 (LTBP-2), indicating that the new protein was bovine LTBP-2. This was confirmed by the specific localization of bovine LTBP-2 cDNA probes to human chromosome 14q24.3, which is the locus of the human LTBP-2 gene. The domain structure of bovine LTBP-2 is very similar to that of the human LTBP-2, containing 20 examples of 6-cysteine epidermal growth factor-like repeats, 16 of which have the consensus sequence for calcium binding, together with 4 examples of 8-cysteine motifs characteristic of fibrillins and LTBP-1. A 4-cysteine sequence which is unique to bovine LTBP-2 and which has similarity to the 8-cysteine motifs was also present. Antibodies raised to two unique bovine LTBP-2 peptides specifically localized in tissue sections to the elastin-associated microfibrils, indicating that LTBP-2 is closely associated with these structures. Immunoblotting experiments identified putative LTBP-2 isoforms as a 260-kDa species released into the medium by cultured elastic tissue cells and as larger 290-and 310-kDa species in tissue extracts. A major proportion of tissue-derived LTBP-2 required treatment with 6 M guanidine for solubilization, indicating that the protein was strongly bound to the microfibrils. Most of the guanidine-solubilized LTBP-2 appeared to be monomeric, indicating that it was not involved in disulfide-bonded aggregation either with itself or with latent TGF-␤. Additional LTBP-2 was resistant to solubilization with 6 M guanidine but was readily extracted with a reductive saline solution. This treatment is relatively specific for solubilization of microfibrillar constituents including fibrillin 1 and microfibril-associated glycoprotein. Therefore, it can be inferred that some LTBP-2 is bound covalently to the microfibrils by reducible disulfide linkages. The evidence suggests that LTBP-2 has a direct role in elastic fiber structure and assembly which may be independent of its growth factor-binding properties. Thus, LTBP-2 appears to share functional characteristics with both LTBP-1 and fibrillins.

Hormonal alterations and diminished sexual quality of life among obese men are related to degree of obesity, and both are improved after gastric bypass surgery.

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Elastic fibers consist primarily of an amorphous elastin core associated with microfibrils, 10 -12 nm in diameter, containing fibrillins and microfibril-associated glycoproteins (MAGPs). To investigate the interaction of MAGP-1 with tropoelastin and fibrillin-1, we expressed human MAGP-1 as a T7-tag fusion protein in Escherichia coli. Refolding of the purified protein produced a soluble form of MAGP-1 that displayed saturable binding to tropoelastin. Fragments of tropoelastin corresponding to the N-terminal, C-terminal, and central regions of the molecule were used to characterize the MAGP-1 binding site. Cleavage of tropoelastin with kallikrein, which cleaves after Arg 515 in the central region of the molecule, disrupted the interaction, suggesting that the separated N-and C-terminal fragments were insufficient to determine MAGP-1 binding to intact tropoelastin. In addition, no evidence of an interaction was observed between MAGP-1 and a tropoelastin construct consisting of domains 17-27 that brackets the kallikrein cleavage site, suggesting a complex mechanism of interaction between the two molecules. Binding of MAGP-1 was also tested with overlapping recombinant fibrillin-1 fragments. MAGP-1 bound to a region at the N terminus of fibrillin-1 in a calcium-dependent manner. In summary, these results suggest a model for the interaction of elastin with the microfibrillar scaffold.Elastic fibers are composed of an amorphous core, consisting mainly of elastin, surrounded by 10 -12 nm microfibrils composed of fibrillins, MAGPs 1 and several other components. During elastic fiber synthesis, the microfibrils appear before the amorphous core and are believed to act as a scaffold for the deposition of tropoelastin. The incorporation of tropoelastin into the nascent elastic fiber is likely to depend on its interactions with microfibrillar proteins and its ability to self-associate through the process of coacervation. Self-association through coacervation involves the hydrophobic domains of the tropoelastin molecule (1, 2). The C-terminal domain, which contains the only two cysteine residues of tropoelastin has been proposed as the site of interaction with the microfibrillar components through the formation of a basic, intramolecular disulfide-bonded loop (3). Antibodies directed against this region disrupt fiber formation in vitro (4), while in lamb ductus arteriosus, loss of the C terminus in a 52-kDa proteolytically derived tropoelastin product prevents incorporation into the fiber (5).Microfibrils appear ultrastructurally after rotary shadowing as beaded filaments with a periodicity of 50 -55 nm (6). The main structural protein of the microfibrils, fibrillin-1, is periodically arranged, with the N and C termini in or close to the beads (7). Another component of microfibrils, originally identified in nuchal ligaments, is a 31-kDa glycoprotein termed MAGP-1 (8). MAGP-1 has been localized by immunogold-labeling to the beaded structures of the microfibrils (9). Both structural components, fibrillin-1 and MAGP-1, are coval...