Crystal Structure of Imaginal Disc Growth Factor-2

Imaginal disc growth factor-2 (IDGF-2) is a member of a recently described family of Drosophila melanogaster-soluble polypeptide growth factors that promote cell proliferation in imaginal discs. Although their precise mode of action has not been established, IDGFs cooperate with insulin in stimulating the growth of imaginal disc cells. We report the crystal structure of IDGF-2 at 1.3-A resolution. The structure shows the classical (betaalpha)(8) barrel-fold of family 18 glycosyl hydrolases, with an insertion of an alpha + beta domain similar to that of Serratia marcescens chitinases A and B. However, amino acid substitutions in the consensus catalytic sequence of chitinases give IDGF-2 a less negatively charged environment in its putative ligand-binding site and preclude the nucleophilic attack mechanism of chitin hydrolysis. Particularly important is the replacement of Glu by Gln at position 132, which has been shown to abolish enzymatic activity in chitinases. Nevertheless, a modest conservation of residues that participate in oligosaccharide recognition suggests that IDGF-2 could bind carbohydrates, assuming several conformational changes to open the partially occluded binding site. Thus, IDGFs may have evolved from chitinases to acquire new functions as growth factors, interacting with cell surface glycoproteins implicated in growth-promoting processes, such as the Drosophila insulin receptor.Fil: Varela, Paloma F.. University of Maryland; Estados UnidosFil: Llera, Andrea Sabina. University of Maryland; Estados Unidos. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Mariuzza, Roy A.. University of Maryland; Estados UnidosFil: Tormo, José. Universidad Autónoma de Madrid; Españ

The Rise and Fall of "Respectable" Spanish Liberalism, 1808-1923: An Explanatory Framework

The article focuses on the reasons behind both the consolidation of what I have termed “respectable” liberalism between the 1830s and the 1840s and its subsequent decline and fall between 1900 and 1923. In understanding both processes I study the links established between “respectable” liberals and propertied elites, the monarchy, and the Church. In the first phase these links served to consolidate the liberal polity. However, they also meant that many tenets of liberal ideology were compromised. Free elections were undermined by the operation of caciquismo, monarchs established a powerful position, and despite the Church hierarchy working with liberalism, the doctrine espoused by much of the Church was still shaped by the Counter-Reformation. Hence, “respectable” liberalism failed to achieve a popular social base. And the liberal order was increasingly denigrated as part of the corrupt “oligarchy” that ruled Spain. Worse still, between 1916 and 1923 the Church, monarch, and the propertied elite increasingly abandoned the liberal Monarchist Restoration. Hence when General Primo de Rivera launched his coup the rug was pulled from under the liberals’ feet and there was no one to cushion the fall

ATLANTIC-CAMTRAPS: a dataset of medium and large terrestrial mammal communities in the Atlantic Forest of South America

Our understanding of mammal ecology has always been hindered by the difficulties of observing species in closed tropical forests. Camera trapping has become a major advance for monitoring terrestrial mammals in biodiversity rich ecosystems. Here we compiled one of the largest datasets of inventories of terrestrial mammal communities for the Neotropical region based on camera trapping studies. The dataset comprises 170 surveys of medium to large terrestrial mammals using camera traps conducted in 144 areas by 74 studies, covering six vegetation types of tropical and subtropical Atlantic Forest of South America (Brazil and Argentina), and present data on species composition and richness. The complete dataset comprises 53,438 independent records of 83 species of mammals, includes 10 species of marsupials, 15 rodents, 20 carnivores, eight ungulates and six armadillos. Species richness averaged 13 species (±6.07 SD) per site. Only six species occurred in more than 50% of the sites: the domestic dog Canis familiaris, crab-eating fox Cerdocyon thous, tayra Eira barbara, south American coati Nasua nasua, crab-eating raccoon Procyon cancrivorus and the nine-banded armadillo Dasypus novemcinctus. The information contained in this dataset can be used to understand macroecological patterns of biodiversity, community, and population structure, but also to evaluate the ecological consequences of fragmentation, defaunation, and trophic interactions. © 2017 by the Ecological Society of Americ

Mortality from gastrointestinal congenital anomalies at 264 hospitals in 74 low-income, middle-income, and high-income countries: a multicentre, international, prospective cohort study

Summary Background Congenital anomalies are the fifth leading cause of mortality in children younger than 5 years globally. Many gastrointestinal congenital anomalies are fatal without timely access to neonatal surgical care, but few studies have been done on these conditions in low-income and middle-income countries (LMICs). We compared outcomes of the seven most common gastrointestinal congenital anomalies in low-income, middle-income, and high-income countries globally, and identified factors associated with mortality. Methods We did a multicentre, international prospective cohort study of patients younger than 16 years, presenting to hospital for the first time with oesophageal atresia, congenital diaphragmatic hernia, intestinal atresia, gastroschisis, exomphalos, anorectal malformation, and Hirschsprung’s disease. Recruitment was of consecutive patients for a minimum of 1 month between October, 2018, and April, 2019. We collected data on patient demographics, clinical status, interventions, and outcomes using the REDCap platform. Patients were followed up for 30 days after primary intervention, or 30 days after admission if they did not receive an intervention. The primary outcome was all-cause, in-hospital mortality for all conditions combined and each condition individually, stratified by country income status. We did a complete case analysis. Findings We included 3849 patients with 3975 study conditions (560 with oesophageal atresia, 448 with congenital diaphragmatic hernia, 681 with intestinal atresia, 453 with gastroschisis, 325 with exomphalos, 991 with anorectal malformation, and 517 with Hirschsprung’s disease) from 264 hospitals (89 in high-income countries, 166 in middleincome countries, and nine in low-income countries) in 74 countries. Of the 3849 patients, 2231 (58·0%) were male. Median gestational age at birth was 38 weeks (IQR 36–39) and median bodyweight at presentation was 2·8 kg (2·3–3·3). Mortality among all patients was 37 (39·8%) of 93 in low-income countries, 583 (20·4%) of 2860 in middle-income countries, and 50 (5·6%) of 896 in high-income countries (p<0·0001 between all country income groups). Gastroschisis had the greatest difference in mortality between country income strata (nine [90·0%] of ten in lowincome countries, 97 [31·9%] of 304 in middle-income countries, and two [1·4%] of 139 in high-income countries; p≤0·0001 between all country income groups). Factors significantly associated with higher mortality for all patients combined included country income status (low-income vs high-income countries, risk ratio 2·78 [95% CI 1·88–4·11], p<0·0001; middle-income vs high-income countries, 2·11 [1·59–2·79], p<0·0001), sepsis at presentation (1·20 [1·04–1·40], p=0·016), higher American Society of Anesthesiologists (ASA) score at primary intervention (ASA 4–5 vs ASA 1–2, 1·82 [1·40–2·35], p<0·0001; ASA 3 vs ASA 1–2, 1·58, [1·30–1·92], p<0·0001]), surgical safety checklist not used (1·39 [1·02–1·90], p=0·035), and ventilation or parenteral nutrition unavailable when needed (ventilation 1·96, [1·41–2·71], p=0·0001; parenteral nutrition 1·35, [1·05–1·74], p=0·018). Administration of parenteral nutrition (0·61, [0·47–0·79], p=0·0002) and use of a peripherally inserted central catheter (0·65 [0·50–0·86], p=0·0024) or percutaneous central line (0·69 [0·48–1·00], p=0·049) were associated with lower mortality. Interpretation Unacceptable differences in mortality exist for gastrointestinal congenital anomalies between lowincome, middle-income, and high-income countries. Improving access to quality neonatal surgical care in LMICs will be vital to achieve Sustainable Development Goal 3.2 of ending preventable deaths in neonates and children younger than 5 years by 2030

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Crystallization and preliminary X-ray diffraction analysis of boar seminal plasma spermadhesin PSP-I/PSP-II, a heterodimer of two CUB domains

3 pags, 1 figs, 1 tabsBoar spermadhesin PSP-I/PSP-II (M(r) 29,000-30,000), a non-covalent heterodimer of two CUB domains, was crystallized in two crystal forms. Complete diffraction data sets for hexagonal (space group P61,522) and trigonal (space group P31,221) crystals have been collected up to 2.9 and 2.5 Å resolution, respectively. Cell constants of the hexagonal and trigonal crystal forms are a = b = 87.2 Å, c = 152.4 Å, and a = b = 96.2 Å, c = 70.8 Å, respectively. The calculated packing parameters (V(m)) are 2.8 and 3.2 Å3/Da for the hexagonal and trigonal crystal forms, respectively, indicating that, in both cases, the asymmetric unit is constituted by one PSP-I/PSP-II heterodimer. This paper reports the first crystals of a protein built up by a CUB domain architecture.This work has been financed by grants T6 114/3-1 from the Deutsche Forschungsgemeinschaft, Bonn, Germany, and PB92-0096 and PB93-0120 from the Dirección General de Investigación Científica y Técnica, Madrid, Spain. The authors wish to thank Dr. Guillermo Gimenez Gallego (Centre de Investigaciones Biológicas, CSIC, Madrid) for N-terminal sequence analyses, and Dr. Angel Vegas (Institute de Quimiea-Fisica, CSIC, Madrid) for helping with space group determination. X-ray diffraction data of hexagonal crystals with a 300 mm diameter Image Plate system were recorded in Prof. Robert Huber's department at the Max-Planck-lnstitut for Biochemie, Martinsried, Germany. Traveling was financed by Acciones Integradas Hispano-Aleman

Structural plasticity of the N-terminal capping helix of the TPR domain of kinesin light chain.

Kinesin1 plays a major role in neuronal transport by recruiting many different cargos through its kinesin light chain (KLC). Various structurally unrelated cargos interact with the conserved tetratricopeptide repeat (TPR) domain of KLC. The N-terminal capping helix of the TPR domain exhibits an atypical sequence and structural features that may contribute to the versatility of the TPR domain to bind different cargos. We determined crystal structures of the TPR domain of both KLC1 and KLC2 encompassing the N-terminal capping helix and show that this helix exhibits two distinct and defined orientations relative to the rest of the TPR domain. Such a difference in orientation gives rise, at the N-terminal part of the groove, to the formation of one hydrophobic pocket, as well as to electrostatic variations at the groove surface. We present a comprehensive structural analysis of available KLC1/2-TPR domain structures that highlights that ligand binding into the groove can be specific of one or the other N-terminal capping helix orientations. Further, structural analysis reveals that the N-terminal capping helix is always involved in crystal packing contacts, especially in a TPR1:TPR1' contact which highlights its propensity to be a protein-protein interaction site. Together, these results underline that the structural plasticity of the N-terminal capping helix might represent a structural determinant for TPR domain structural versatility in cargo binding

The TPR1:TPR1’ crystal packing contacts.

<p>(A) Superposition of KLC2-TPR^[A1-B6] (this study, blue) and KLC1-TPR^[A1-B6] (3NF1, orange). TPR domain superposition is done on the B1 helix of the main molecule. For clarity, only the TPR domain of KLC2-TPR^[A1-B6] (this study) is shown in grey in a cartoon representation as a template, but A1 helices are shown in color. The symmetry molecule at the TPR1:TPR1’ contact is shown in color. A 180° view is shown below. (B) Zoom at the TPR1:TPR1’ contact for the KLC1-TPR^[A1-B6] crystal form (3NF1, orange). (C) Zoom at the TPR1:TPR1’ contact for the KLC2-TPR^[A1-B6] crystal form (this study, blue). The orientation is conserved between (B) and (C) with the reference B1 helices (grey) indicated with a black axis. Some residues involved in the TPR1:TPR1’ contact are indicated in sticks.</p

Relationship between the N-terminal capping A1 helix position and the TPR groove content.

<p>(A) Superposition of the unnatural His-tag fusion of KLC1-TPR^[A1-B6] (3NF1, orange) and the natural LFP-motif from KLC2-^LFPTPR^[A1-B6] (5FJY, green). TPR domain superposition is done on the TPR2 motif. Only the KLC1-TPR[A1-B6] structure (3NF1) is shown for clarity in white cartoon surrounded by a transparent surface representation. The “OUT” A1 helix is indicated in dark grey. The Phe202* from the His-tag linker (3NF1, orange) is shown in sticks. (B) The KLC1-TPR^[A1-B5] (this study) contacting the B5’-sym helix (pink). KLC1-TPR^[A1-B5] is shown in white cartoon surrounded by a transparent surface representation. The “OUT” A1 helix is indicated in dark grey. The Phe416’ from the αB5’-sym (pink) is shown in sticks.</p

Structure-based sequence alignment of the TPR domain of KLC1 and KLC2.

<p>Sequence alignment is organized by TPR motif. Sequence accession number for human KLC1 is AAH08881.1a, and for mouse KLC2 is NP_032477.2. Helices A and B from each TPR motif are underlined and indicated in red. Helices in the non-TPR region are also indicated in bold. Position 2 of the TPR1 motif that differs from other TPR motifs is highlighted in green. Sequence difference between KLC1 and KLC2 that discriminate JIP1 cargo binding is colored in blue.</p