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Background: Just over 300,000 women give birth in Australia each year. It is important for health care providers, managers, and policy makers know what women want from their care so services can be provided appropriately. This review is a part of the Midwifery Futures Project, which aims to prepare the midwifery workforce to best address the needs of women. The aim of this review was to describe and analyse current literature on the maternity care needs of women in Australia., Methods: A scoping review methodology was used, guided by the Joanna Briggs Institute framework. A systematic search of the literature identified 9023 studies, and 59 met inclusion criteria: being peer-reviewed research focusing on maternity care needs, conducted in Australian populations, from 2012 to 2023. The studies were analysed using inductive content analysis., Results: Four themes were developed: Continuity of care, being seen and heard, being safe, and being enabled. Continuity of care, especially a desire for midwifery continuity of care, was the central theme, as it was a tool supporting women to be seen and heard, safe, and enabled., Conclusion: This review highlights that women in Australia consistently want access to midwifery continuity of care as an enabler for addressing their maternity care needs. Transforming Australian maternity care policy and service provision towards continuity would better meet women's needs., Competing Interests: Declaration of Competing Interest Caroline Homer declares she is the current Editor-in-Chief of Women & Birth. The Deputy Editor, Prof Linda Sweet, managed this submission and made the final decision. All other authors have no further conflicts to declare., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

The intrinsic editing capacities of aminoacyl-tRNA synthetases ensure a high-fidelity translation of the amino acids that possess effective non-cognate aminoacylation surrogates. The dominant error-correction pathway comprises deacylation of misaminoacylated tRNA within the aminoacyl-tRNA synthetase editing site. To assess the origin of specificity of Escherichia coli leucyl-tRNA synthetase (LeuRS) against the cognate aminoacylation product in editing, we followed binding and catalysis independently using cognate leucyl- and non-cognate norvalyl-tRNA Leu and their non-hydrolyzable analogues. We found that the amino acid part (leucine versus norvaline) of (mis)aminoacyl-tRNAs can contribute approximately 10-fold to ground-state discrimination at the editing site. In sharp contrast, the rate of deacylation of leucyl- and norvalyl-tRNA Leu differed by about 10 4 -fold. We further established the critical role for the A76 3'-OH group of the tRNA Leu in post-transfer editing, which supports the substrate-assisted deacylation mechanism. Interestingly, the abrogation of the LeuRS specificity determinant threonine 252 did not improve the affinity of the editing site for the cognate leucine as expected, but instead substantially enhanced the rate of leucyl-tRNA Leu hydrolysis. In line with that, molecular dynamics simulations revealed that the wild-type enzyme, but not the T252A mutant, enforced leucine to adopt the side-chain conformation that promotes the steric exclusion of a putative catalytic water. Our data demonstrated that the LeuRS editing site exhibits amino acid specificity of kinetic origin, arguing against the anticipated prominent role of steric exclusion in the rejection of leucine. This feature distinguishes editing from the synthetic site, which relies on ground-state discrimination in amino acid selection., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Negative strand RNA virus (NSV) genomes are never free, but always found assembled with multiple copies of their nucleoprotein, as RNPs. A flurry of papers describing the X-ray crystal structures of several segmented NSV nucleoproteins have recently appeared. The most significant feature of these various structures is that the arms that are used to oligomerize the nucleoproteins on their genome RNAs are highly flexible, permitting these RNPs to assume virtually unlimited geometries. The structural flexibility of segmented NSV RNPs is undoubtedly important in all aspects of their biology, including genome replication and circularization, and the selection of one copy of each segment for packaging into virus particles., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Aminoacyl-tRNA synthetases are validated molecular targets for anti-infective drug discovery because of their essentiality in protein synthesis. Thanks to genome sequencing, it is now possible to systematically study aminoacyl-tRNA synthetases from human eukaryotic parasites as putative targets for novel drug discovery. As part of a program targeting class IIb asparaginyl-tRNA synthetases (AsnRS) from the parasitic nematode Brugia malayi for anti-filarial drugs, we report the complete structure of a eukaryotic AsnRS. Metazoan and fungal AsnRS differ from their bacterial homologues by the addition of a conserved N-terminal extension of about 110 residues whose structure we have determined by solution NMR for the B. malayi enzyme. In addition, we solved by X-ray crystallography a series of structures of the catalytically active N-terminally truncated enzyme (residues 112-548), allowing the structural basis for the mechanism of asparagine activation to be elucidated. The N-terminal domain contains a structured region with a novel fold featuring a lysine-rich helix that is shown by NMR to interact with tRNA. This is connected by an unstructured tether to the remainder of the enzyme, which is highly similar to the known structure of bacterial AsnRS. These data enable a model of the complete AsnRS-tRNA complex to be constructed., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

Leucyl-tRNA synthetase (LeuRS) specifically links leucine to the 3' end of tRNA(leu) isoacceptors. The overall accuracy of the two-step aminoacylation reaction is enhanced by an editing domain that hydrolyzes mischarged tRNAs, notably ile-tRNA(leu). We present crystal structures of the editing domain from two eukaryotic cytosolic LeuRS: human and fungal pathogen Candida albicans. In comparison with previous structures of the editing domain from bacterial and archeal kingdoms, these structures show that the LeuRS editing domain has a conserved structural core containing the active site for hydrolysis, with distinct bacterial, archeal, or eukaryotic specific peripheral insertions. It was recently shown that the benzoxaborole antifungal compound AN2690 (5-fluoro-1,3-dihydro-1-hydroxy-1,2-benzoxaborole) inhibits LeuRS by forming a covalent adduct with the 3' adenosine of tRNA(leu) at the editing site, thus locking the enzyme in an inactive conformation. To provide a structural basis for enhancing the specificity of these benzoxaborole antifungals, we determined the structure at 2.2 A resolution of the C. albicans editing domain in complex with a related compound, AN3018 (6-(ethylamino)-5-fluorobenzo[c][1,2]oxaborol-1(3H)-ol), using AMP as a surrogate for the 3' adenosine of tRNA(leu). The interactions between the AN3018-AMP adduct and C. albicans LeuRS are similar to those previously observed for bacterial LeuRS with the AN2690 adduct, with an additional hydrogen bond to the extra ethylamine group. However, compared to bacteria, eukaryotic cytosolic LeuRS editing domains contain an extra helix that closes over the active site, largely burying the adduct and providing additional direct and water-mediated contacts. Small differences between the human domain and the fungal domain could be exploited to enhance fungal specificity.

The heterodimeric nuclear cap-binding complex (CBC) specifically recognizes the monomethylguanosine 5' cap structure of the eukaryotic RNA polymerase II transcripts such as mRNA and U snRNA. The binding is essential for nuclear maturation of mRNA, for nuclear export of U snRNA in metazoans, and for nonsense-mediated decay of mRNA and the pioneer round of translation. We analysed the recognition of the cap by native human CBC and mutants in which each tyrosine that stacks with the 7-methylguanosine moiety was replaced by phenylalanine or alanine and both tyrosines were replaced by phenylalanines. The equilibrium association constants (K(as)) for two selected cap analogues, P(1)-7-methylguanosine-5' P(3)-guanosine-5' triphosphate and 7-methylguanosine triphosphate, were determined by two independent methods, fluorescence titration and surface plasmon resonance. We could distinguish two tyrosines, Y43 and Y20, in stabilization of the cap inside the CBC-binding pocket. In particular, lack of Y20 in CBC leads to a greater affinity of the mono- than the dinucleotide cap analogue, in contrast to the wild-type protein. A crucial role of cation-pi stacking in the mechanism of the specific cap recognition by CBC was postulated from the comparison of the experimentally derived Gibbs free binding energy (DeltaG degrees) with the stacking energy (DeltaE) of the 7-methylguanosine/Y binary and ternary complexes calculated by the Møller-Plesset second-order perturbation method. The resulting kinetic model of the association between the capped RNA and CBC, based on the experimental data and quantum calculations, is discussed with respect to the "CBC-to-eukaryotic initiation factor 4E handoff" of mRNA.

SecA is the preprotein translocase ATPase subunit and a superfamily 2 (SF2) RNA helicase. Here we present the 2 A crystal structures of the Escherichia coli SecA homodimer in the apo form and in complex with ATP, ADP and adenosine 5'-[beta,gamma-imido]triphosphate (AMP-PNP). Each monomer contains the SF2 ATPase core (DEAD motor) built of two domains (nucleotide binding domain, NBD and intramolecular regulator of ATPase 2, IRA2), the preprotein binding domain (PBD), which is inserted in NBD and a carboxy-terminal domain (C-domain) linked to IRA2. The structures of the nucleotide complexes of SecA identify an interfacial nucleotide-binding cleft located between the two DEAD motor domains and residues critical for ATP catalysis. The dimer comprises two virtually identical protomers associating in an antiparallel fashion. Dimerization is mediated solely through extensive contacts of the DEAD motor domains leaving the C-domain facing outwards from the dimerization core. This dimerization mode explains the effect of functionally important mutations and is completely different from the dimerization models proposed for other SecA structures. The repercussion of these findings on translocase assembly and catalysis is discussed.

NOD1 is a cytosolic signalling host pattern-recognition receptor composed of a caspase-activating and recruitment domain (CARD), a nucleotide-binding and oligomerization domain (NOD) and leucine-rich repeats. It plays a crucial role in innate immunity by activating the NF-kappaB pathway via its downstream effector the kinase RICK (RIP2) following the recognition of a specific bacterial ligand. RICK is recruited by NOD1 through interaction of their respective CARDs. Here we present the high resolution NMR structure of the NOD1 CARD. It is generally similar to other CARDs of known structure, consisting of six tightly packed helices, although the length and orientation of the last helix is unusual. Mutations in both the NOD1 and RICK CARD domains were assayed by immuno-precipitation of cell lysates and in vivo NF-kappaB activation in order to define residues important for CARD-CARD interaction and downstream signalling. The results show that the interaction is critically dependent on three acidic residues on NOD1 CARD and three basic residues on RICK CARD and thus is likely to have a strong electrostatic component, similar to other characterised CARD-CARD interactions.

Objectives: Children presenting with sport related injuries (SRIs) as a result of soccer, rugby and gaelic football are frequently seen in an emergency medicine (EM) setting in Ireland. A comparison of the demographics of injuries in these three sports has however not previously been performed. The purpose of this study was to provide up-to-date data on the nature of these SRIs., Method: Data was collected retrospectively on all children (<17 years of age), injured in these three sports, presenting to an emergency medicine department over 6 months, and was entered into a database for analysis., Results: Retrospective analysis was performed on 23,000 charts, and 409 SRIs were identified over a 6-month period. None of the children reported using any form of protective gear, and 27% reported a previous presentation to the emergency department with a SRI. Most injuries were as a result of soccer (56%), with 24% occurring in gaelic football, and 20% occurring in rugby. The predominant mechanism of injury was different in each sport, in soccer-falls (38%), in gaelic football-collisions with objects (balls) (37%), and in rugby-collision with persons (55%). Although the predominant type of injury in soccer and gaelic football was a fracture, accounting for 50% and 42% of injuries, respectively, in rugby however, skin/soft tissue injuries presented more commonly, accounting for 44% of injuries. When the general site of injury was investigated, the upper limb accounted for the majority of SRIs in each sport. In the management of SRIs, oral analgesics were prescribed in 50%, however, it was observed that no use was made of topical, intramuscular or rectal analgesic routes of administration. In addition it was observed that RICE/general injury advice was given in only 27%, physiotherapy was requested in 2%, and no injury prevention advice was given to any child. Overall, 8% required admission., Conclusions: The data provided from this study may raise awareness of the nature of SRIs affecting children in each of these three sports, and may be useful in formulating much needed injury prevention strategies.

Ladder fall injuries are associated with a wide spectrum of injury patterns. However, the healthcare cost of these injuries is unknown. The aim of this study was to determine the healthcare cost and duration of the morbidity associated with ladder fall injuries. A retrospective observational study involving patients with ladder injuries who presented to a Level 1 Trauma Centre over a 3-year period was performed. Patients then underwent a structured telephone interview to provide information about the duration of their disability and unemployment. There were 72 patients in the study, of whom 89% were male. Thirteen patients (18%) required hospital admission. The median length and cost of hospital stay was 1 week and 3555 (US$ 3950), respectively. The median duration of disability and unemployment was 6 weeks. The longest duration of disability was associated with foot fractures. The majority of patients fell between 5 and 10ft, and fell at work. The upper extremity was the most commonly injured anatomical region. There were no fatalities. Ladder injury falls are expensive to the health service and may warrant investment in their prevention.

We describe the recognition by Thermus thermophilus prolyl-tRNA synthetase (ProRSTT) of proline, ATP and prolyl-adenylate and the sequential conformational changes occurring when the substrates bind and the activated intermediate is formed. Proline and ATP binding cause respectively conformational changes in the proline binding loop and motif 2 loop. However formation of the activated intermediate is necessary for the final conformational ordering of a ten residue peptide ("ordering loop") close to the active site which would appear to be essential for functional tRNA 3' end binding. These induced fit conformational changes ensure that the enzyme is highly specific for proline activation and aminoacylation. We also present new structures of apo and AMP bound histidyl-tRNA synthetase (HisRS) from T. thermophilus which we compare to our previous structures of the histidine and histidyl-adenylate bound enzyme. Qualitatively, similar results to those observed with T. thermophilus prolyl-tRNA synthetase are found. However histidine binding is sufficient to induce the co-operative ordering of the topologically equivalent histidine binding loop and ordering loop. These two examples contrast with most other class II aminoacyl-tRNA synthetases whose pocket for the cognate amino acid side-chain is largely preformed. T. thermophilus prolyl-tRNA synthetase appears to be the second class II aminoacyl-tRNA synthetase, after HisRS, to use a positively charged amino acid instead of a divalent cation to catalyse the amino acid activation reaction., (Copyright 2001 Academic Press.)

The three-dimensional structure of the seryl-tRNA synthetase from Thermus thermophilus has been determined and refined at 2.5 A resolution. The final model consists of a dimer of 421 residues each and 190 water molecules. The R-factor is 18.4% for all the data between 10 and 2.5 A resolution. The structure is very similar to that of the homologous enzyme from Escherichia coli, with an r.m.s. difference of 1.5 A for the 357 alpha-carbon atoms considered equivalent. The comparison of the two structures indicates increased hydrophobicity, reduced conformational entropy and reduced torsional strain as possible mechanisms by which thermostability is obtained in the enzyme from the thermophile.

The adenovirus fibre is a trimeric protein with a globular head on a long thin shaft that projects from the twelve fivefold vertices of the virion. The shaft region of the fibre primary sequence has a unique pseudo-repeating motif of 15 residues. Using constraints derived from sequence analysis, the trimeric nature of the fibre, the experimental determination of the shaft length and general knowledge about protein structure, an atomic model of the fibre shaft has been constructed by computer modelling techniques. In the final model the three monomers form a left-handed triple-helical structure with threefold symmetry and with successive 15-residue repeats on the same chain related by an axial rise of 13.1 A and a left-handed azimuthal rotation of close to 300 degrees. Three threefold related beta-sheets with short strands are formed by inter-monomer main-chain hydrogen bonds giving rise to superhelical ribbons covering the surface of the shaft. The model satisfies criteria of extensive hydrogen bonding, reasonable backbone torsion angles, burial of most hydrophobic residues and good packing of the hydrophobic core. Furthermore, the model is consistent with the observed shaft length of about 290 A and its calculated X-ray fibre diffraction patterns shows the characteristic features found in the diffraction pattern of crystals of fibre, notably layer lines with a spacing of about 1/26 A-1 and strong meridional intensity at 1/4.4 A-1.

The complex between seryl-tRNA synthetase and its cognate tRNA from the extreme thermophile Thermus thermophilus has been crystallized from ammonium sulphate solutions. Two different tetragonal crystal forms have been characterized, both diffracting to about 6 A using synchrotron radiation. One form grows as large bipyramids and has cell dimensions a = b = 127 A, c = 467 A, and the second form occurs as long, thin square prisms with cell dimensions a = b = 101 A, c = 471 A. Analysis of washed and dissolved crystals demonstrates the presence of both protein and tRNA.

Helicopters have been used for the evaluation of civilian casualties since the 1960s. This trend has been increasing and a number of helicopter emergency services have now commenced in the UK. Despite these developments, little attention has been paid to their exact role, and the potential benefits to patients. In addition, the costs of such services are high, and the risks to patients and staff from air accidents are considerable. Similar or improved results may be obtained through the use of more cost-effective ground-based units. Judicious placement of both helicopter emergency services and land-based 'flying squads' in an integrated accident service may contribute usefully to better care of patients. However, enthusiasm for helicopters should not lead to a waste of resources and should be accompanied by careful consideration, planning and audit of their use.

An analysis by electron microscopy in amorphous ice and X-ray diffraction of four types of three-dimensional crystals of adenovirus fibre is presented. Fibre from adenovirus type 2 (Ad2) crystallizes in two forms depending on whether it is native or cleaved near the N terminus at Tyr17. Fibre from Ad5 also crystallizes in two forms, both of which contained fibre cleaved at Tyr17. Analysis of the packing of the fibres in each of these crystals suggests that the overall length of the fibre may be considerably longer (about 350 to 370 A) than previously reported. Crystals of cleaved Ad2 fibre are of sufficient quality to be characterized by X-ray diffraction. They are of space group C2 and cell dimensions a = 134.4 A, b = 77.6 A, c = 539.4 A, beta = 92.7 degrees. These crystals are remarkable in that, despite being monoclinic, the ab plane forms a perfect hexagonal lattice. This is explained by a trigonal packing of the trimeric fibre heads in the crystal. A similar feature is found for one type of Ad5 crystal, although the hexagonal lattice is 12% smaller. The crystals of cleaved Ad2 show very strong meridional intensity at a Bragg spacing of 4.4 A and weaker diffuse intensity corresponding to layer-lines of spacing 26.4 A. This must reflect the quasiperiodicity of the structure of the fibre shaft, which is apparent in the primary sequence. The occurrence of these features combined with the new determination of the length of the fibre (see also the accompanying paper) require a reappraisal of the cross-beta model of the fibre shaft proposed by Green et al.

Neutron-scattering in combination with quasi-elastic light-scattering and electron microscopy was used to derive a model for the capsid structure of the Top a-t component of alfalfa mosaic virus (AMV-Ta-t). In the electron microscope, AMV-Ta-t appears as an irregular ellipsoidal particle with apparent dimensions 275 (+/- 31) A X 225 (+/- 22) A. Assuming that the particles are monodisperse, model calculations show that the neutron-scattering data are best explained by an oblate ellipsoidal shape for the virion with external dimensions 284 A X 284 A X 216 A. Based on this result, and in combination with the known composition of the virion, it is suggested that the capsid structure could be based on a deltahedron with 52 pointgroup symmetry and comprising 120 subunits. Such a model would imply a greater deviation from equivalent subunit interactions than normally necessary in icosahedral capsids. The neutron and photon correlation data, however, do not allow us to rule out the possibility that Top a-t is a slightly polydisperse preparation of irregular prolate shapes with mean dimensions 312 A X 232 A X 232 A. Both possibilities support the concept of alfalfa mosaic virus coat protein being capable of a wide range of intersubunit interactions, this flexibility resulting in considerable polymorphism in capsid structures.

Crystals of seryl-tRNA synthetase from Escherichia coli can be grown from ammonium sulphate/octyl glucoside solutions in two days. The crystals appear to be very suitable for X-ray analysis, diffracting to at least 2.8 A resolution and being resistant to radiation damage. The crystals are monoclinic (space group C2) with cell parameters a = 148.2 A, b = 90.6 A, c = 69.5 A and beta = 119.0 degrees. Depending on whether the asymmetric unit is the enzyme monomer (Mr 48,414) or dimer the Vm value would be either 4.12 or 2.10 A3/dalton. Although the former would indicate a rather high solvent content, other proteins crystallized in the presence of octyl glucoside have Vm values similar to this.

A real space method allowing the reconstruction of negatively stained crystalline objects from a limited number of projections is presented. The method is based on the assumption that only two density levels are required to describe an ideally negatively stained object (that of the volume occupied by the object and that of the volume occupied by the stain). The method is illustrated by the reconstruction of the asymmetric unit of catalase microcrystals using only the three principal projections. It is shown that other projections can then be predicted to a good approximation.

A detailed analysis is presented of the small-angle neutron scattering curves of homogeneous solutions of influenza B virus, both intact and after treatment with bromelain, which removes the external glycoprotein spikes. The two sets of data are consistent with the following low-resolution structure: the virus particles are spherical, about 1200 A in diameter and of Mr about 180 X 10(6). The lipid bilayer is centred at a radius of 425 A, is 40 A to 50 A thick and constitutes 25% to 28% of the virus mass. The surface glycoproteins, predominantly haemagglutinin, contribute 40% to 46% of the total mass. Surprisingly little protein is found in the interior of the virus. It is suggested that the reason for this is that many particles do not contain the full complement of ribonucleoprotein complexes. These results are in good agreement with recent scanning transmission electron microscopic measurements of molecular mass and cryo-electron microscopic observations of the same preparations. Appendix 1 describes a new method of deriving spherical shell models from contrast variation neutron scattering data on viruses, in which scattering curves from all measured contrasts are used simultaneously. There is also a discussion of the assumptions and limitations implicit in the structural interpretation of such models, with emphasis on viruses containing lipid bilayers. Appendix 2 examines the effect on the scattering curves of various arrangements of the surface glycoproteins.

Neutron-scattering with contrast variation has been used to derive a model for the radial distribution of protein and RNA in the VRU strain of alfalfa mosaic virus. The RNA is distributed uniformly throughout the interior of the capsid up to a radius of 65 A and the protein coat extends from 65 to 100 A. It was found necessary to distinguish between two regions within the protein coat: one with mainly hydrophobic amino acids and another with more hydrophylic amino acids. Only a very small part of the protein penetrates into the RNA. Using X-ray scattering, no indication was found for long or short-range order in the packing of the RNA in the virion.

The experimental inelastic neutron scattering spectrum of a protein, the bovine pancreatic trypsin inhibitor (BPTI), in a powder sample is presented together with the generalized density of states, G(omega), as a function of the frequency, omega, derived from the scattering data. The experimental results are compared with calculations from two different normal mode analyses of BPTI. One of these, based on an improved model, gives a calculated spectrum and density of states in general agreement with those obtained experimentally; the other, based on an earlier model, shows considerable disagreement. The important improvements in the newer normal mode analysis are the explicit treatment of all atoms (non-polar as well as polar hydrogens are included) and a modified truncation scheme for the long-range electrostatic interactions. The fact that the inelastic neutron scattering measurements can distinguish between the two theoretical models makes clear their utility for the analysis of protein dynamics.

The influenza C glycoprotein is clearly seen to be a trimer in specimens prepared with uranyl stains. Three-dimensional reconstructions from naturally occurring hexagonal arrays show that at low resolution (approximately 30 A) the influenza C glycoprotein exhibits similar features to the haemagglutinin glycoprotein of influenza A. Both have a triangular stalk near the membrane. Further from the membrane, the stalk becomes broader and the monomers more separated, leaving an open centre. The molecule narrows at the top. The regions of greatest contact between adjacent trimers in the arrays are situated nearer the distal end of the molecule. These contact zones can be related to equivalent zones on the influenza A haemagglutinin. Differences between the structure of the influenza A haemagglutinin glycoprotein determined by X-ray analysis and reconstructions of the influenza C glycoprotein are greatest at either end of the molecule, where the reconstructions are least reliable. Ordered glycoprotein arrays have not been observed on influenza C virions incubated at low pH. The staining patterns of glycoproteins on intact virions are essentially determined by the pH at which the virus is incubated, and the stain type, but not the pH of the stain.