Impact of bariatric surgery, lifestyle change, and pharmacotherapy on fertility in men with obesity: a systematic review protocol.

Objective: This review will determine whether various health interventions designed to reduce weight (lifestyle change, bariatric surgery, pharmacotherapy) in men with obesity are associated with improved fertility markers. The review will also establish whether the degree of weight loss achieved through these methods is associated with improvement.

Introduction: Current preconception guidelines provide limited information for men with obesity.

Novel agents to treat adrenal insufficiency: findings of preclinical and early clinical trials.

Introduction: Adrenal insufficiency currently affects over 300/million population, with higher morbidity and mortality compared to the general population. Current glucocorticoid replacement therapy is limited by a lack of reliable biomarkers to guide dosing, inter-patient variation in metabolism and narrow therapeutic window. Increased morbidity and mortality may relate to unappreciated under- or over-exposure to glucocorticoids and impaired cortisol circadian rhythm.

Association of alcohol and bone mineral density dependent on type of alcohol consumed.

Introduction: Osteoporosis prevalence will increase in coming decades, with significant financial and economic implications. Whilst alcohol excess has significant detrimental impacts on bone mineral density (BMD), knowledge of low-volume consumption is inconsistent. Type of alcohol may mediate impact on BMD and warrants further investigation.

Sperm DNA damage: The possible link between obesity and male infertility, an update of the current literature.

Obesity prevalence worldwide is increasing significantly. Whilst maternal obesity has clear detrimental impacts on fertility, pregnancy and foetal outcomes, more recently there has been an increasing focus on the role of paternal obesity in human fertility. Recent meta-analyses have indicated that obesity in men negatively affects basic sperm parameters such as sperm count, concentration and motility, increases the incidence of infertility and reduces the chances of conception.

A chiral phosphazane reagent strategy for the determination of enantiomeric excess of amines.

Methods for measuring enantiomeric excess () of organic molecules by NMR spectroscopy provide rapid analysis using a standard technique that is readily available. Commonly this is accomplished by chiral derivatisation of the detector molecule (producing a chiral derivatisation agent, CDA), which is reacted with the mixture of enantiomers under investigation. However, these CDAs have almost exclusively been based on carbon frameworks, which are generally costly and/or difficult to prepare.

Uncovering the Hidden Landscape of Tris(4-pyridyl) Ligands: Topological Complexity Derived from the Bridgehead.

Supramolecular main group chemistry is a developing field which parallels the conventional domain of metallo-organic chemistry. Little explored building blocks in this area are main group metal-based ligands which have the appropriate donor symmetry to build desired molecular or extended arrangements. Tris(pyridyl) main group ligands (E(py) , E=main group metal) are potentially highly versatile building blocks since shifting the N-donor arms from the 2- to the 3-positions and 4-positions provides a very simple way of changing the ligand character from mononuclear/chelating to multidentate/metal-bridging.

Lipshutz-type bis(amido)argentates for directed argentation.

Bis(amido)argentate (TMP)Ag(CN)Li (, TMP-Ag-ate; TMP = 2,2,6,6-tetramethylpiperidido) was designed as a tool for chemoselective aromatic functionalization unprecedented directed argentation (DAg). X-Ray crystallographic analysis showed that takes a structure analogous to that of the corresponding Lipshutz cuprate. DAg with this TMP-Ag-ate afforded multifunctional aromatics in high yields in processes that exhibited high chemoselectivity and compatibility with a wide range of functional groups.

Arthropod segmentation.

There is now compelling evidence that many arthropods pattern their segments using a clock-and-wavefront mechanism, analogous to that operating during vertebrate somitogenesis. In this Review, we discuss how the arthropod segmentation clock generates a repeating sequence of pair-rule gene expression, and how this is converted into a segment-polarity pattern by 'timing factor' wavefronts associated with axial extension. We argue that the gene regulatory network that patterns segments may be relatively conserved, although the timing of segmentation varies widely, and double-segment periodicity appears to have evolved at least twice.

A new route for the efficient metalation of unfunctionalized aromatics.

The synthesis and isolation of a novel bimetallic species formed by reacting two equivalents of TMPLi with CuCl in the presence of EtO are reported. X-ray crystallography reveals the EtO-free tetranuclear aggregate (TMPCu)(TMPLi) , which formally results from the catenation of dimers of TMPLi and TMPCu. NMR spectroscopy confirms that, upon dissolution in hydrocarbon media, the crystals fail to form a conventional Gilman cuprate dimer.

Evidence for the temporal regulation of insect segmentation by a conserved sequence of transcription factors.

Long-germ insects, such as the fruit fly , pattern their segments simultaneously, whereas short-germ insects, such as the beetle , pattern their segments sequentially, from anterior to posterior. While the two modes of segmentation at first appear quite distinct, much of this difference might simply reflect developmental heterochrony. We now show here that, in both and , segment patterning occurs within a common framework of sequential Caudal, Dichaete, and Odd-paired expression.

Metal exchange in lithiocuprates: implications for our understanding of structure and reactivity.

New reagents have been sought for directed cupration in which the use of cyanide reagents is eliminated. CuOCN reacts with excess TMPLi (TMP = 2,2,6,6-tetramethylpiperidide) in the presence of limited donor solvent to give crystals that are best represented as (TMP)CuLi(OCN)Li(THF) , whereby both Lipshutz-type lithiocuprate (TMP)Cu(OCN)Li(THF) and trinuclear (TMP)(OCN)Li(THF) are expressed. Treatment of a hydrocarbon solution of TMPCuLi with LiOCN and THF gives pure .

Selective lability of ruthenium(II) arene amino acid complexes.

A series of organometallic complexes of the form [(PhH)Ru(amino acid)](+) have been synthesized using amino acids able to act as tridentate ligands. The straightforward syntheses gave enantiomerically pure complexes with two stereogenic centers due to the enantiopurity of the chelating ligands. Complexes were characterized in the solid-state and/or solution-state where the stability of the complex allowed.

New avenues in the directed deprotometallation of aromatics: recent advances in directed cupration.

Recent advances in the selective deprotometallation of aromatic reagents using alkali metal cuprates are reported. The ability of these synergic bases to effect deprotonation under the influence of a directing group is explored in the context of achieving new and more efficient organic transformations whilst encouraging greater ancillary group tolerance by the base. Developments in our understanding of the structural chemistry of alkali metal cuprates are reported, with both Gilman cuprates of the type R2CuLi and Lipshutz and related cuprates of the type R2Cu(X)Li2 (X = inorganic anion) elucidated and rationalised in terms of ligand sterics.

Structural effects in lithiocuprate chemistry: the elucidation of reactive pentametallic complexes.

TMPLi (TMP=2,2,6,6-tetramethylpiperidide) reacts with Cu(I) salts in the presence of Et2O to give the dimers [{(TMP)2Cu(X)Li2 (OEt2)}2] (X=CN, halide). In contrast, the use of DMPLi (DMP=cis-2,6-dimethylpiperidide) gives an unprecedented structural motif; [{(DMP)2CuLi(OEt2)}2LiX] (X=halide). This formulation suggests a hitherto unexplored route to the in situ formation of Gilman-type bases that are of proven reactivity in directed ortho cupration.

Tc-knirps plays different roles in the specification of antennal and mandibular parasegment boundaries and is regulated by a pair-rule gene in the beetle Tribolium castaneum.

Background: The Drosophila larval head is evolutionarily derived at the genetic and morphological level. In the beetle Tribolium castaneum, development of the larval head more closely resembles the ancestral arthropod condition. Unlike in Drosophila, a knirps homologue (Tc-kni) is required for development of the antennae and mandibles.

A segmentation clock with two-segment periodicity in insects.

Vertebrate segmentation relies on a mechanism characterized by oscillating gene expression. Whether this mechanism is used by other segmented animals has been controversial. Rigorous proof of cyclic expression during arthropod segmentation has been lacking.

Early asymmetries in maternal transcript distribution associated with a cortical microtubule network and a polar body in the beetle Tribolium castaneum.

The localization of maternal mRNAs during oogenesis plays a central role in axial specification in some insects. Here we describe a polar body-associated asymmetry in maternal transcript distribution in pre-blastoderm eggs of the beetle Tribolium castaneum. Since the position of the polar body marks the future dorsal side of the embryo, we have investigated whether this asymmetry in mRNA distribution plays a role in dorsal-ventral axis specification.

EGF signaling and the origin of axial polarity among the insects.

The eggs of insects are unusual in that they often have bilateral symmetry when they are laid, indicating that both anterior-posterior (AP) and dorsal-ventral (DV) symmetries are broken during oogenesis. The molecular basis of this process is well understood in Drosophila melanogaster, in which symmetry breaking events for both axes depend on the asymmetric position of the oocyte nucleus and on germline-soma signaling mediated by the Tgf alpha-like epidermal growth factor (EGF) ligand Gurken. Germline-soma signaling interactions centered around the oocyte nucleus have been proposed in other insect species, but the molecular nature of these interactions has not been elucidated.

Forward genetics in Tribolium castaneum: opening new avenues of research in arthropod biology.

A recent paper in BMC Biology reports the first large-scale insertional mutagenesis screen in a non-drosophilid insect, the red flour beetle Tribolium castaneum. This screen marks the beginning of a non-biased, 'forward genetics' approach to the study of genetic mechanisms operating in Tribolium.

The evolution of developmental gene networks: lessons from comparative studies on holometabolous insects.

Recent comparative studies have revealed significant differences in the developmental gene networks operating in three holometabolous insects: the beetle Tribolium castaneum, the parasitic wasp Nasonia vitripennis and the fruitfly Drosophila melanogaster. I discuss these differences in relation to divergent and convergent changes in cellular embryology. I speculate on how segmentation gene networks have evolved to operate in divergent embryological contexts, and highlight the role that co-option might have played in this process.

The dynamics of yolk deposition in the desert locust Schistocerca gregaria.

Injection of the protein dye Fast Green or the fluid-phase probe fluorescein dextran into the haemolymph of vitellogenic female desert locusts (Schistocerca gregaria) resulted in their incorporation into oocytes. We used Fast Green to study the physical dynamics of yolk deposition during vitellogenesis. Timed maternal injections of Fast Green reveal that yolk deposition and oocyte growth are inextricably linked during vitellogenesis, and that little or no yolk movement occurs within oocytes prior to embryogenesis.

The evolution of hexapod engrailed-family genes: evidence for conservation and concerted evolution.

Phylogenetic analyses imply that multiple engrailed-family gene duplications occurred during hexapod evolution, a view supported by previous reports of only a single engrailed-family gene in members of the grasshopper genus Schistocerca and in the beetle Tribolium castaneum. Here, we report the cloning of a second engrailed-family gene from Schistocerca gregaria and present evidence for two engrailed-family genes from four additional hexapod species. We also report the existence of a second engrailed-family gene in the Tribolium genome.

Arthropod segmentation: beyond the Drosophila paradigm.

Most of our knowledge about the mechanisms of segmentation in arthropods comes from work on Drosophila melanogaster. In recent years it has become clear that this mechanism is far from universal, and different arthropod groups have distinct modes of segmentation that operate through divergent genetic mechanisms. We review recent data from a range of arthropods, identifying which features of the D.