The annual market in Africa for substandard and non-registered veterinary medicine is estimated to be 400 million United States dollars,5 equal to that of the officially registered, quality-assured ...veterinary drug market.6 Numerous cases of antimicrobial resistance in humans have been traced to resistant microbes suspected of originating in livestock,7,8 which is particularly concerning as infected livestock can be asymptomatic.8 Transmission of resistant bacteria from livestock to humans can occur through the consumption of meat, direct contact with colonized animals or manure spread in the environment.7 The strongest correlation between interspecies pathogen transmission is observed in countries with policies to reduce agricultural antibiotic use. Poor-quality medicines that provide sub-therapeutic doses of active pharmaceutical ingredient, whether due to inadequate amounts of pharmaceutical, ineffective release, presence of impurities or degradation of compounds, are believed to contribute to antimicrobial resistance by exposing microbes to a level of antibiotic that will not effectively kill the whole microbial population.10 Poor-quality veterinary medicine as a contributor to antimicrobial resistance has been mentioned anecdotally in the literature, but systematic studies are lacking. Pharmaceutical quality is often assessed using high-performance liquid chromatography on field samples, an expensive, laboratory-based test that requires well-trained staff and a long waiting period for results.To sufficiently survey veterinary medicine quality in low- and middle-income countries, portable technologies that can provide quantitative information about the active pharmaceutical ingredient in an efficient and affordable manner are needed. The International Cooperation on Harmonization of Technical Requirements for Registration of Veterinary Medicinal Products programme develops global standards for veterinary medicine and helps countries establish drug registration protocols.15 The World Organization for Animal Health National Focal Point for Veterinary Products has established a network of global veterinary product experts, with each member nation represented by a local authority on veterinary health and medicine.16 Post-market identification Organizations concerned with antimicrobial resistance should work to raise awareness among government stakeholders in low- and middle-income countries about the issues surrounding poor-quality veterinary medicine, encouraging these countries to prioritize secure supply chains for veterinary medicine.
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CEKLJ, DOBA, IZUM, KILJ, NUK, ODKLJ, OILJ, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK, VSZLJ
Adherent cells undergo remarkable changes in shape during cell division. However, the functional interplay between cell adhesion turnover and the mitotic machinery is poorly understood. The ...endo/exocytic trafficking of integrins is regulated by the small GTPase Rab21, which associates with several integrin α subunits. Here, we show that targeted trafficking of integrins to and from the cleavage furrow is required for successful cytokinesis, and that this is regulated by Rab21. Rab21 activity, integrin-Rab21 association, and integrin endocytosis are all necessary for normal cytokinesis, which becomes impaired when integrin-mediated adhesion at the cleavage furrow fails. We also describe a chromosomal deletion and loss of Rab21 gene expression in human cancer, which leads to the accumulation of multinucleate cells. Importantly, reintroduction of Rab21 rescued this phenotype. In conclusion, Rab21-regulated integrin trafficking is essential for normal cell division, and its defects may contribute to multinucleation and genomic instability, which are hallmarks of cancer.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Integrins are critical for platelet adhesion and aggregation during arterial thrombosis and hemostasis. Although the platelet-specific αIIbβ3 integrin is known to be crucial for these processes, the ...in vivo role of β1 integrins is a matter of debate. Here we demonstrate that mice expressing reduced levels of β1 integrins or an activation-deficient β1 integrin show strongly reduced platelet adhesion to collagen in vitro and in a carotis ligation model in vivo. Interestingly, hypomorphic mice expressing only 3% of β1 integrins on platelets show normal bleeding times despite reduced platelet adhesion. The residual 3% of β1 integrins are able to trigger intracellular signals driving Rac-1−dependent granule release required for platelet aggregation and hemostasis. Our findings support a model, in which platelet β1 integrins serve as an important signaling receptor rather than an adhesion receptor in vivo and therefore promote β1 integrins as a promising and so far clinically unemployed antithrombotic target.
•Platelet β1 integrin−mediated signals control granule secretion and hemostasis•β1 integrin−mediated outside-in signaling is independent of direct kindlin-integrin interaction
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
A key feature of integrins is their ability to regulate the affinity for ligands, a process termed integrin activation. The final step in integrin activation is talin binding to the NPXY motif of the ...integrin β cytoplasmic domains. Talin binding disrupts the salt bridge between the α/β tails, leading to tail separation and integrin activation. We analyzed mice in which we mutated the tyrosines of the β1 tail and the membrane-proximal aspartic acid required for the salt bridge. Tyrosine-to-alanine substitutions abolished β1 integrin functions and led to a β1 integrin-null phenotype in vivo. Surprisingly, neither the substitution of the tyrosines with phenylalanine nor the aspartic acid with alanine resulted in an obvious defect. These data suggest that the NPXY motifs of the β1 integrin tail are essential for β1 integrin function, whereas tyrosine phosphorylation and the membrane-proximal salt bridge between α and β1 tails have no apparent function under physiological conditions in vivo.
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BFBNIB, NUK, PNG, UL, UM, UPUK
Helicobacter pylori infection shows a worldwide prevalence of around 50%. However, only a minority of infected individuals develop clinical symptoms or diseases. The presence of H. pylori virulence ...factors, such as CagA and VacA, has been associated with disease development, but assessment of virulence factor presence requires gastric biopsies. Here, we evaluate the H. pylori recomLine test for risk stratification of infected patients by comparing the test score and immune recognition of type I or type II strains defined by the virulence factors CagA, VacA, GroEL, UreA, HcpC, and gGT with patient’s disease status according to histology. Moreover, the immune responses of eradicated individuals from two different populations were analysed. Their immune response frequencies and intensities against all antigens except CagA declined below the detection limit. CagA was particularly long lasting in both independent populations. An isolated CagA band often represents past eradication with a likelihood of 88.7%. In addition, a high recomLine score was significantly associated with high-grade gastritis, atrophy, intestinal metaplasia, and gastric cancer. Thus, the recomLine is a sensitive and specific noninvasive test for detecting serum responses against H. pylori in actively infected and eradicated individuals. Moreover, it allows stratifying patients according to their disease state.
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DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UILJ, UKNU, UL, UM, UPUK
Infection with
(
) occurs in 50% of the world population, and is associated with the development of ulcer and gastric cancer. Serological diagnostic tests indicate an
infection by detecting ...antibodies directed against
proteins. In addition to line blots, multiplex assay platforms provide smart solutions for the simultaneous analysis of antibody responses towards several
proteins. We used seven
proteins (FliD, gGT, GroEL, HpaA, CagA, VacA, and HP0231) and an
lysate for the development of a multiplex serological assay on a novel microfluidic platform. The reaction limited binding regime in the microfluidic channels allows for a short incubation time of 35 min. The developed assay showed very high sensitivity (99%) and specificity (100%). Besides sensitivity and specificity, the technical validation (intra-assay CV = 3.7 ± 1.2% and inter-assay CV = 5.5 ± 1.2%) demonstrates that our assay is also a robust tool for the analysis of the
-specific antibody response. The integration of the virulence factors CagA and VacA allow for the assessment of the risk for gastric cancer development. The short assay time and the performance of the platform shows the potential for implementation of such assays in a clinical setting.
Integrin functions are controlled by regulating their affinity for ligand, and by the efficient recycling of intact integrins through endosomes. Here we demonstrate that the Kindlin-binding site in ...the β1-integrin cytoplasmic domain serves as a molecular switch enabling the sequential binding of two FERM-domain-containing proteins in different cellular compartments. When β1 integrins are at the plasma membrane, Kindlins control ligand-binding affinity. However, when they are internalized, Kindlins dissociate from integrins and sorting nexin 17 (SNX17) is recruited to free β1-integrin tails in early endosomes to prevent β1-integrin degradation, leading to their recycling back to the cell surface. Our results identify SNX17 as a β1-integrin-tail-binding protein that interacts with the free Kindlin-binding site in endosomes to stabilize β1 integrins, resulting in their recycling to the cell surface where they can be reused.
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DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Multidrug resistance among Gram-negative bacteria is a major global public health threat. Metallo-β-lactamases (MBLs) target the most widely used antibiotic class, the β-lactams, including the most ...recent generation of carbapenems. Interspecies spread renders these enzymes a serious clinical threat, and there are no clinically available inhibitors. We present the crystal structures of IMP-13, a structurally uncharacterized MBL from the Gram-negative bacterium
found in clinical outbreaks globally, and characterize the binding using solution nuclear magnetic resonance spectroscopy and molecular dynamics simulations. The crystal structures of apo IMP-13 and IMP-13 bound to four clinically relevant carbapenem antibiotics (doripenem, ertapenem, imipenem, and meropenem) are presented. Active-site plasticity and the active-site loop, where a tryptophan residue stabilizes the antibiotic core scaffold, are essential to the substrate-binding mechanism. The conserved carbapenem scaffold plays the most significant role in IMP-13 binding, explaining the broad substrate specificity. The observed plasticity and substrate-locking mechanism provide opportunities for rational drug design of novel metallo-β-lactamase inhibitors, essential in the fight against antibiotic resistance.
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