bluuebunny/crossref_metadata_2025_split huggingface dataset:
Administration of platelet concentrates suspended in bicarbonated Ringer's solution in children who had platelet transfusion reactions
Authors: Kobayashi J. , Yanagisawa R. , Ono T. , Tatsuzawa Y. , Tokutake Y. , Kubota N. , Hidaka E. , Sakashita K. , Kojima S. , Shimodaira S. , Nakamura T. 
Published: October 2017

Background and ObjectivesAdverse reactions to platelet transfusions are a problem. Children with primary haematological and malignant diseases may experience allergic transfusion reactions (ATRs) to platelet concentrates (PCs), which can be prevented by giving washed PCs. A new platelet additive solution, using bicarbonated Ringer's solution and acid–citrate–dextrose formula A (BRS‐A), may be better for platelet washing and storage, but clinical data are scarce.Materials and MethodsA retrospective cohort study for consecutive cases was performed between 2013 and 2017. For 24 months, we transfused washed PCs containing BRS‐A to children with primary haematological and malignant diseases and previous adverse reactions. Patients transfused with conventional PCs (containing residual plasma) were assigned as controls, and results were compared in terms of frequency of ATRs, corrected count increment (CCI) and occurrence of bleeding. We also studied children transfused with PCs washed by a different system as historical controls.ResultsThirty‐two patients received 377 conventional PC transfusions. ATRs occurred in 12 (37·5%) patients from transfused with 18 (4·8%) bags. Thirteen patients, who experienced reactions to regular PCs in plasma, then received 119 transfusion bags of washed PCs containing BRS‐A, and none had ATRs to washed PCs containing BRS‐A. Before study period, six patients transfused 137 classical washed PCs with different platelet additive solution, under same indication, ATRs occurred in one (16·7%) patient from transfused with one (0·7%) bags. CCIs (24 h) in were lower with classical washed PCs (1·26 ± 0·54) compared to regular PCs in plasma (2·07 ± 0·76) (P < 0·001), but there was no difference between washed PCs containing BRS‐A (2·14 ± 0·77) and regular PCs (2·21 ± 0·79) (P = 0·769), and we saw no post‐transfusion bleeding.ConclusionWashed PCs containing BRS‐A appear to prevent ATRs without loss of transfusion efficacy in children with primary haematological and malignant diseases. Their efficacy should be further evaluated through larger prospective clinical trials.
Effects of carbon monoxide on early dysfunction and microangiopathy following GalT‐KO porcine pulmonary xenotransplantation in cynomolgus monkeys
Authors: Sahara Hisashi , Sekijima Mitsuhiro , Ariyoshi Yuichi , Kawai Akihiro , Miura Kohei , Waki Shiori , Nathan Louras , Tomita Yusuke , Iwanaga Takehiro , Nakano Kazuaki , Matsunari Hitomi , Date Hiroshi , Nagashima Hiroshi , Shimizu Akira , Yamada Kazuhiko 
Published: October 2017

AbstractBackgroundDespite progress in the current genetic manipulation of donor pigs, most non‐human primates were lost within a day of receiving porcine lung transplants. We previously reported that carbon monoxide (CO) treatment improved pulmonary function in an allogeneic lung transplant (LTx) model using miniature swine. In this study, we evaluated whether the perioperative treatment with low‐dose inhalation of CO has beneficial effects on porcine lung xenografts in cynomolgus monkeys (cynos).MethodsEight cynos received orthotopic left LTx using either α‐1,3‐galactosyltransferase knockout (GalT‐KO; n = 2) or GalT‐KO with human decay accelerating factor (hDAF) (GalT‐KO/hDAF; n = 6) swine donors. These eight animals were divided into three groups. In Group 1 (n = 2), neither donor nor recipients received CO therapy. In Group 2 (n = 4), donors were treated with inhaled CO for 180‐minute. In Group 3 (n = 2), both donors and recipients were treated with CO (donor: 180‐minute; recipient: 360‐minute). Concentration of inhaled CO was adjusted based on measured levels of carboxyhemoglobin in the blood (15%‐20%).ResultsTwo recipients survived for 3 days; 75 hours (no‐CO) and 80 hours (CO in both the donor and the recipient), respectively. Histology showed less inflammatory cell infiltrates, intravascular thrombi, and hemorrhage in the 80‐hour survivor with the CO treatment than the 75‐hours non‐CO treatment. Anti–non‐Gal cytotoxicity levels did not affect the early loss of the grafts. Although CO treatment did not prolong overall xeno lung graft survival, the recipient/donor CO treatment helped to maintain platelet counts and inhibit TNF‐α and IL‐6 secretion at 2 hours after revascularization of grafts. In addition, lung xenografts that were received recipient/donor CO therapy demonstrated fewer macrophage and neutrophil infiltrates. Infiltrating macrophages as well as alveolar epithelial cells in the CO‐treated graft expressed heme oxygenase‐1.ConclusionAlthough further investigation is required, CO treatment may provide a beneficial strategy for pulmonary xenografts.
Molecular Diagnostics of Arthroconidial Yeasts, Frequent Pulmonary Opportunists
Authors: Kaplan Engin , Al-Hatmi Abdullah M. S. , Ilkit Macit , Gerrits van den Ende A. H. G. , Hagen Ferry , Meis Jacques F. , de Hoog G. Sybren 
Published: October 2017

ABSTRACT

Magnusiomyces capitatus
and
Saprochaete clavata
are members of the clade of arthroconidial yeasts that represent emerging opportunistic pulmonary pathogens in immunocompromised patients. Given that standard ribosomal DNA (rDNA) identification often provides confusing results, in this study, we analyzed 34 isolates with the goal of finding new genetic markers for classification using multilocus sequencing and amplified fragment length polymorphism (AFLP). The interspecific similarity obtained using rDNA markers (the internal transcribed spacer [ITS] and large subunit regions) was in the range of 96 to 99%, whereas that obtained using protein-coding loci (
Rbp2
,
Act
, and
Tef1α
) was lower at 89.4 to 95.2%. Ultimately,
Rbp2
was selected as the best marker for species distinction. On the basis of cloned ITS data, some strains proved to be misidentified in comparison with the identities obtained with phenotypic characters, protein sequences, and AFLP profiles, indicating that different copies of the ribosomal operon were present in a single species. Antifungal susceptibility testing revealed that voriconazole had the lowest MIC against
M. capitatus
, while amphotericin B had the lowest MIC against
S. clavata
. Both species exhibited
in vitro
resistance to fluconazole and micafungin.
Cryo-Electron Microscopy Structure of Porcine Deltacoronavirus Spike Protein in the Prefusion State
Authors: Shang Jian , Zheng Yuan , Yang Yang , Liu Chang , Geng Qibin , Tai Wanbo , Du Lanying , Zhou Yusen , Zhang Wei , Li Fang 
Published: October 2017

ABSTRACT
Coronavirus spike proteins from different genera are divergent, although they all mediate coronavirus entry into cells by binding to host receptors and fusing viral and cell membranes. Here, we determined the cryo-electron microscopy structure of porcine deltacoronavirus (PdCoV) spike protein at 3.3-Å resolution. The trimeric protein contains three receptor-binding S1 subunits that tightly pack into a crown-like structure and three membrane fusion S2 subunits that form a stalk. Each S1 subunit contains two domains, an N-terminal domain (S1-NTD) and C-terminal domain (S1-CTD). PdCoV S1-NTD has the same structural fold as alpha- and betacoronavirus S1-NTDs as well as host galectins, and it recognizes sugar as its potential receptor. PdCoV S1-CTD has the same structural fold as alphacoronavirus S1-CTDs, but its structure differs from that of betacoronavirus S1-CTDs. PdCoV S1-CTD binds to an unidentified receptor on host cell surfaces. PdCoV S2 is locked in the prefusion conformation by structural restraint of S1 from a different monomeric subunit. PdCoV spike possesses several structural features that may facilitate immune evasion by the virus, such as its compact structure, concealed receptor-binding sites, and shielded critical epitopes. Overall, this study reveals that deltacoronavirus spikes are structurally and evolutionally more closely related to alphacoronavirus spikes than to betacoronavirus spikes; it also has implications for the receptor recognition, membrane fusion, and immune evasion by deltacoronaviruses as well as coronaviruses in general.

IMPORTANCE
In this study, we determined the cryo-electron microscopy structure of porcine deltacoronavirus (PdCoV) spike protein at a 3.3-Å resolution. This is the first atomic structure of a spike protein from the deltacoronavirus genus, which is divergent in amino acid sequences from the well-studied alpha- and betacoronavirus spike proteins. Here, we described the overall structure of the PdCoV spike and the detailed structure of each of its structural elements. Moreover, we analyzed the functions of each of the structural elements. Based on the structures and functions of these structural elements, we discussed the evolution of PdCoV spike protein in relation to the spike proteins from other coronavirus genera. This study combines the structure, function, and evolution of PdCoV spike protein and provides many insights into its receptor recognition, membrane fusion, and immune evasion.
Epistastic Interactions within the Junín Virus Envelope Glycoprotein Complex Provide an Evolutionary Barrier to Reversion in the Live-Attenuated Candid#1 Vaccine
Authors: York Joanne , Nunberg Jack H. 
Published: October 2017

ABSTRACT
The Candid#1 strain of Junín virus was developed using a conventional attenuation strategy of serial passage in nonhost animals and cultured cells. The live-attenuated Candid#1 vaccine is used in Argentina to protect at-risk individuals against Argentine hemorrhagic fever, but it has not been licensed in the United States. Recent studies have revealed that Candid#1 attenuation is entirely dependent on a phenylalanine-to-isoleucine substitution at position 427 in the fusion subunit (GP2) of the viral envelope glycoprotein complex (GPC), thereby raising concerns regarding the potential for reversion to virulence. In this study, we report the identification and characterization of an intragenic epistatic interaction between the attenuating F427I mutation in GP2 and a lysine-to-serine mutation at position 33 in the stable signal peptide (SSP) subunit of GPC, and we demonstrate the utility of this interaction in creating an evolutionary barrier against reversion to the pathogenic genotype. In the presence of the wild-type F427 residue, the K33S mutation abrogates the ability of ectopically expressed GPC to mediate membrane fusion at endosomal pH. This defect is rescued by the attenuating F427I mutation. We show that the recombinant Candid#1 (rCan) virus bearing K33S GPC is viable and retains its attenuated genotype under cell culture conditions that readily select for reversion in the parental rCan virus. If back-mutation to F427 offers an accessible pathway to increase fitness in rCan, reversion in K33S-GPC rCan is likely to be lethal. The epistatic interaction between K33S and F427I thus may minimize the likelihood of reversion and enhance safety in a second-generation Candid#1 vaccine.

IMPORTANCE
The live-attenuated Candid#1 vaccine strain of Junín virus is used to protect against Argentine hemorrhagic fever. Recent findings that a single missense mutation in the viral envelope glycoprotein complex (GPC) is responsible for attenuation raise the prospect of facile reversion to pathogenicity. Here, we characterize a genetic interaction between GPC subunits that evolutionarily forces retention of the attenuating mutation. By incorporating this secondary mutation into Candid#1 GPC, we hope to minimize the likelihood of reversion and enhance safety in a second-generation Candid#1 vaccine. A similar approach may guide the design of live-attenuated vaccines against Lassa and other arenaviral hemorrhagic fevers.
Stability and Expression Levels of HLA-C on the Cell Membrane Modulate HIV-1 Infectivity
Authors: Parolini Francesca , Biswas Priscilla , Serena Michela , Sironi Francesca , Muraro Valentina , Guizzardi Elisabetta , Cazzoletti Lucia , Scupoli Maria Teresa , Gibellini Davide , Ugolotti Elisabetta , Biassoni Roberto , Beretta Alberto , Malnati Mauro , Romanelli Maria Grazia , Zipeto Donato 
Published: October 2017

ABSTRACTHLA-C expression is associated with a differential ability to control HIV-1 infection. Higher HLA-C levels may lead to better control of HIV-1 infection through both a higher efficiency of antigen presentation to cytotoxic T lymphocytes and the triggering of activating killer immunoglobulin-like receptors on NK cells, whereas lower levels may provide poor HIV-1 control and rapid progression to AIDS. We characterized the relative amounts of HLA-C heterotrimers (heavy chain/β2microglobulin [β2m]/peptide) and HLA-C free heavy chains on peripheral blood mononuclear cells (PBMCs) from healthy blood donors harboring both alleles with stable or unstable binding to β2m/peptide. We analyzed the stability of HLA-C heterotrimers of different allotypes and the infectivity of HIV-1 virions produced by PBMCs with various allotypes. We observed significant differences in HLA-C heterotrimer stability and in expression levels. We found that R5 HIV-1 virions produced by PBMCs harboring unstable HLA-C alleles were more infectious than those produced by PBMCs carrying the stable variants. We propose that HIV-1 infectivity might depend both on the amounts of HLA-C molecules and on their stability as trimeric complex. According to this model, individuals with low-expression HLA-C alleles and unstable binding to β2m/peptide might have worse control of HIV-1 infection and an intrinsically higher capacity to support viral replication.IMPORTANCEFollowing HIV-1 infection, some people advance rapidly to AIDS while others have slow disease progression. HLA-C, a molecule involved in immunity, is a key determinant of HIV-1 control. Here we reveal how HLA-C variants contribute to the modulation of viral infectivity. HLA-C is present on the cell surface in two different conformations. The immunologically active conformation is part of a complex that includes β2microglobulin/peptide; the other conformation is not bound to β2microglobulin/peptide and can associate with HIV-1, increasing its infectivity. Individuals with HLA-C variants with a predominance of immunologically active conformations would display stronger immunity to HIV-1, reduced viral infectivity and effective control of HIV-1 infection, while subjects with HLA-C variants that easily dissociate from β2microglobulin/peptide would have a reduced immunological response to HIV-1 and produce more infectious virions. This study provides new information that could be useful in the design of novel vaccine strategies and therapeutic approaches to HIV-1.
Role of Granulocyte-Macrophage Colony-Stimulating Factor Production by T Cells duringMycobacterium tuberculosisInfection
Authors: Rothchild Alissa C. , Stowell Britni , Goyal Girija , Nunes-Alves Cláudio , Yang Qianting , Papavinasasundaram Kadamba , Sassetti Christopher M. , Dranoff Glenn , Chen Xinchun , Lee Jinhee , Behar Samuel M. 
Published: October 2017

ABSTRACTMice deficient for granulocyte-macrophage colony-stimulating factor (GM-CSF−/−) are highly susceptible to infection withMycobacterium tuberculosis, and clinical data have shown that anti-GM-CSF neutralizing antibodies can lead to increased susceptibility to tuberculosis in otherwise healthy people. GM-CSF activates human and murine macrophages to inhibit intracellularM. tuberculosisgrowth. We have previously shown that GM-CSF produced by iNKT cells inhibits growth ofM. tuberculosis. However, the more general role of T cell-derived GM-CSF during infection has not been defined and how GM-CSF activates macrophages to inhibit bacterial growth is unknown. Here we demonstrate that, in addition to nonconventional T cells, conventional T cells also produce GM-CSF duringM. tuberculosisinfection. Early during infection, nonconventional iNKT cells and γδ T cells are the main source of GM-CSF, a role subsequently assumed by conventional CD4+T cells as the infection progresses.M. tuberculosis-specific T cells producing GM-CSF are also detected in the peripheral blood of infected people. Under conditions where nonhematopoietic production of GM-CSF is deficient, T cell production of GM-CSF is protective and required for control ofM. tuberculosisinfection. However, GM-CSF is not required for T cell-mediated protection in settings where GM-CSF is produced by other cell types. Finally, using anin vitromacrophage infection model, we demonstrate that GM-CSF inhibition ofM. tuberculosisgrowth requires the expression of peroxisome proliferator-activated receptor gamma (PPARγ). Thus, we identified GM-CSF production as a novel T cell effector function. These findings suggest that a strategy augmenting T cell production of GM-CSF could enhance host resistance againstM. tuberculosis.IMPORTANCEMycobacterium tuberculosisis the bacterium that causes tuberculosis, the leading cause of death by any infection worldwide. T cells are critical components of the immune response toMycobacterium tuberculosis. While gamma interferon (IFN-γ) is a key effector function of T cells during infection, a failed phase IIb clinical trial and other studies have revealed that IFN-γ production alone is not sufficient to controlM. tuberculosis. In this study, we demonstrate that CD4+, CD8+, and nonconventional T cells produce GM-CSF duringMycobacterium tuberculosisinfection in mice and in the peripheral blood of infected humans. Under conditions where other sources of GM-CSF are absent, T cell production of GM-CSF is protective and is required for control of infection. GM-CSF activation of macrophages to limit bacterial growth requires host expression of the transcription factor PPARγ. The identification of GM-CSF production as a T cell effector function may inform future host-directed therapy or vaccine designs.
Genome-Wide Discovery of Genes Required for Capsule Production by Uropathogenic
Escherichia coli
Authors: Goh Kelvin G. K. , Phan Minh-Duy , Forde Brian M. , Chong Teik Min , Yin Wai-Fong , Chan Kok-Gan , Ulett Glen C. , Sweet Matthew J. , Beatson Scott A. , Schembri Mark A. 
Published: October 2017

ABSTRACT

Uropathogenic
Escherichia coli
(UPEC) is a major cause of urinary tract and bloodstream infections and possesses an array of virulence factors for colonization, survival, and persistence. One such factor is the polysaccharide K capsule. Among the different K capsule types, the K1 serotype is strongly associated with UPEC infection. In this study, we completely sequenced the K1 UPEC urosepsis strain PA45B and employed a novel combination of a lytic K1 capsule-specific phage, saturated Tn
5
transposon mutagenesis, and high-throughput transposon-directed insertion site sequencing (TraDIS) to identify the complement of genes required for capsule production. Our analysis identified known genes involved in capsule biosynthesis, as well as two additional regulatory genes (
mprA
and
lrhA
) that we characterized at the molecular level. Mutation of
mprA
resulted in protection against K1 phage-mediated killing, a phenotype restored by complementation. We also identified a significantly increased unidirectional Tn
5
insertion frequency upstream of the
lrhA
gene and showed that strong expression of LrhA induced by a constitutive Pcl promoter led to loss of capsule production. Further analysis revealed loss of MprA or overexpression of LrhA affected the transcription of capsule biosynthesis genes in PA45B and increased sensitivity to killing in whole blood. Similar phenotypes were also observed in UPEC strains UTI89 (K1) and CFT073 (K2), demonstrating that the effects were neither strain nor capsule type specific. Overall, this study defined the genome of a UPEC urosepsis isolate and identified and characterized two new regulatory factors that affect UPEC capsule production.

IMPORTANCE
Urinary tract infections (UTIs) are among the most common bacterial infections in humans and are primarily caused by uropathogenic
Escherichia coli
(UPEC). Many UPEC strains express a polysaccharide K capsule that provides protection against host innate immune factors and contributes to survival and persistence during infection. The K1 serotype is one example of a polysaccharide capsule type and is strongly associated with UPEC strains that cause UTIs, bloodstream infections, and meningitis. The number of UTIs caused by antibiotic-resistant UPEC is steadily increasing, highlighting the need to better understand factors (e.g., the capsule) that contribute to UPEC pathogenesis. This study describes the original and novel application of lytic capsule-specific phage killing, saturated Tn
5
transposon mutagenesis, and high-throughput transposon-directed insertion site sequencing to define the entire complement of genes required for capsule production in UPEC. Our comprehensive approach uncovered new genes involved in the regulation of this key virulence determinant.
Sensory Repertoire of Bacterial Chemoreceptors
Authors: Ortega Álvaro , Zhulin Igor B. , Krell Tino 
Published: October 2017

SUMMARY

Chemoreceptors in bacteria detect a variety of signals and feed this information into chemosensory pathways that represent a major mode of signal transduction. The five chemoreceptors from
Escherichia coli
have served as traditional models in the study of this protein family. Genome analyses revealed that many bacteria contain much larger numbers of chemoreceptors with broader sensory capabilities. Chemoreceptors differ in topology, sensing mode, cellular location, and, above all, the type of ligand binding domain (LBD). Here, we highlight LBD diversity using well-established and emerging model organisms as well as genomic surveys. Nearly a hundred different types of protein domains that are found in chemoreceptor sequences are known or predicted LBDs, but only a few of them are ubiquitous. LBDs of the same class recognize different ligands, and conversely, the same ligand can be recognized by structurally different LBDs; however, recent studies began to reveal common characteristics in signal-LBD relationships. Although signals can stimulate chemoreceptors in a variety of different ways, diverse LBDs appear to employ a universal transmembrane signaling mechanism. Current and future studies aim to establish relationships between LBD types, the nature of signals that they recognize, and the mechanisms of signal recognition and transduction.