Neutrophils are the primary cells recruited to inflamed sites during an innate immune response to tissue damage and/or infection. They are finely sensitive to inciting stimuli to reach in great ...numbers and within minutes areas of inflammation and tissue insult. For this effective response, they can detect extracellular chemical gradients and move towards higher concentrations, the so-called chemotaxis process or guided cell migration. This directed neutrophil recruitment is orchestrated by chemoattractants, a chemically diverse group of molecular guidance cues (e.g., lipids, N-formylated peptides, complement, anaphylotoxins and chemokines). Neutrophils respond to these guidance signals in a hierarchical manner and, based on this concept, they can be further subdivided into two groups: “end target” and “intermediary” chemoattractants, the signals of the former dominant over the latter. Neutrophil chemoattractants exert their effects through interaction with heptahelical G protein-coupled receptors (GPCRs) expressed on cell surfaces and the chemotactic response is mainly regulated by the Rho family of GTPases. Additionally, neutrophil behavior might differ and be affected in different complex scenarios such as disease conditions and type of vascular bed in specific organs. Finally, there are different mechanisms to disrupt neutrophil chemotaxis either associated to the resolution of inflammation or to bacterial escape and systemic infection. Therefore, in the present review, we will discuss the different molecular players involved in neutrophil chemotaxis, paying special attention to the different chemoattractants described and the way that they interact intra- and extravascularly for neutrophils to properly reach the target tissue.
Streptococcus pneumoniae (pneumococcus) is an important pathogen responsible for acute invasive and non-invasive infections such as meningitis, sepsis and otitis media, being the major cause of ...community-acquired pneumonia. The fight against pneumococcus is currently hampered both by insufficient vaccine coverage and by rising antimicrobial resistances to traditional antibiotics, making necessary the research on novel targets. Choline binding proteins (CBPs) are a family of polypeptides found in pneumococcus and related species, as well as in some of their associated bacteriophages. They are characterized by a structural organization in two modules: a functional module (FM), and a choline-binding module (CBM) that anchors the protein to the choline residues present in the cell wall through non-covalent interactions. Pneumococcal CBPs include cell wall hydrolases, adhesins and other virulence factors, all playing relevant physiological roles for bacterial viability and virulence. Moreover, many pneumococcal phages also make use of hydrolytic CBPs to fulfill their infectivity cycle. Consequently, CBPs may play a dual role for the development of novel antipneumococcal drugs, both as targets for inhibitors of their binding to the cell wall and as active cell lytic agents (enzybiotics). In this article, we review the current state of knowledge about host- and phage-encoded pneumococcal CBPs, with a special focus on structural issues, together with their perspectives for effective anti-infectious treatments.
The parallel 29Si magic angle spinning nuclear magnetic resonance (MAS NMR) and Fourier-transform infrared study of synthetic micas made it possible to compare structural features of the tetrasilicic ...magnesium mica K(Mg2.5□0.5) Si4O10(OH)2 (TMM) and their K(Mg3)(Si3.5Mg0.5)O10(OH)2 (TMMA) and K(Mg3)(Si3.5Be0.5)O10(OH)2 (TMMB) derivatives. In the TMM mica, SiO4 tetrahedra are elongated in the plane ab and shortened along the c* direction with respect to those of the phlogopite (Phl) K(Mg3)(Si3Al)O10(OH)2. The substitution of Si4+ by R2+ (Mg2+ or Be2+) produces, besides the 29Si MAS NMR signal of Si (3Si) at −91.2 ppm, new components at −84.4 or −87.5 ppm that correspond to Si (2Si1Mg) or Si(2Si1Be) environments. Tetrahedral cation distributions in TMM/TMMA, TMM/TMMB solid solutions are investigated with respect to the TMM/Phl series by means of NMR and Monte Carlo simulations, concluding that divalent Mg2+ and Be2+ are further dispersed than trivalent Al3+ cations in tetrahedral sheets of micas. In three analyzed series, cation distributions display features between those of the homogeneous dispersion of charges of phlogopites and the maximum dispersion of charges of TMM derivatives. In three series, the location of charge deficits that compensate K+ cations changes from octahedral in TMM to tetrahedral sheets in phlogopite and TMMA and TMMB derivatives.
Summary
Polyhydroxyalkanoates (PHAs) are natural polyesters of increasing biotechnological importance that are synthesized by many prokaryotic organisms as carbon and energy storage compounds in ...limiting growth conditions. PHAs accumulate intracellularly in form of inclusion bodies that are covered with a proteinaceous surface layer (granule‐associated proteins or GAPs) conforming a network‐like surface of structural, metabolic and regulatory polypeptides, and configuring the PHA granules as complex and well‐organized subcellular structures that have been designated as ‘carbonosomes’. GAPs include several enzymes related to PHA metabolism (synthases, depolymerases and hydroxylases) together with the so‐called phasins, an heterogeneous group of small‐size proteins that cover most of the PHA granule and that are devoid of catalytic functions but nevertheless play an essential role in granule structure and PHA metabolism. Structurally, phasins are amphiphilic proteins that shield the hydrophobic polymer from the cytoplasm. Here, we summarize the characteristics of the different phasins identified so far from PHA producer organisms and highlight the diverse opportunities that they offer in the Biotechnology field.
Phasins are widespread proteins associated to the surface of polyhydroxyalkanoate (PHA) granules synthetized by prokaryotic organisms. They play essential roles in PHA stability and metabolism, but they also possess remarkable properties that make them suitable for biotechnological applications..
The main objective of this study was to systematically and meta-analytically review the scientific literature on the prevalence of psychopathy in the general adult population. A search in PsycInfo, ...MEDLINE, and PSICODOC identified 15 studies published as of June 2021. Altogether, 16 samples of adults totaling 11,497 people were evaluated. Joint prevalence rates were calculated using reverse variance heterogeneity models. Meta-regression analyses were conducted to examine whether the type of instrument, sex, type of sample, and country influenced prevalence. The meta-analytical results obtained allow us to estimate the prevalence rate of psychopathy in the general adult population at 4.5%. That being said, this rate varies depending on the participants' sex (higher in males), the type of sample from the general population (higher in samples from organizations than in community samples or university students), and the type of instrument used to define psychopathy. In fact, using the PCL-R, which is currently considered the "gold standard" for the assessment and definition of psychopathy, the prevalence is only 1.2%. These results are discussed in the context of the different theoretical perspectives and the existing problems when it comes to defining the construct of psychopathy.
Environmental information provided by free lipids in soil samples collected from control and disturbed plots (Madrid, Spain) was assessed by comparing molecular assemblages of terpenoids and ...distribution patterns of alkanes and fatty acids (FAs) analyzed by gas chromatography–mass spectrometry (GC-MS). Wildfires in pine forests led to increased proportions of retene, dehydroabietin, and simonellite. Friedo-oleananes were characteristic in soils under angiosperms, and norambreinolide-type diterpenes were characteristic in soils encroached by Cistus bushes. Steroids were major compounds in pastured sites. Enhanced Shannon’s lipid biodiversity index in disturbed soils compared with in control soils suggested patterns of recent lipids overlapping a preserved original lipid signature. The extent of the environmental impacts was illustrated as Euclidean distances between paired control and disturbed sites calculated using the compounds in alkyl homologous series as descriptors. As expected, reforestation, bush encroachment, wildfires, and cultivation were reflected by changes in the molecular record of lipids in soils.
The main aim of the study is to evaluate the efficacy of a single dose of sarilumab, in subcutaneous administration, in hospitalised patients with moderate to early severe COVID-19 infection compared ...to the current standard of care, to prevent progression to systemic hyperinflammatory status. Our hypothesis is that use of subcutaneous sarilumab in early stages (window of opportunity) of COVID-19 moderate-severe pneumonia can prevent higher oxygenation requirements through non-invasive and invasive mechanical ventilation and decrease in-hospital stays, as well as death rate. The secondary objectives of the study are to evaluate the safety of sarilumab through hospitalisation and up to day 14 after discharge, compared to the control arm as assessed by incidence of serious and non serious adverse events (SAEs). In addition, as an exploratory objective, to compare the baseline clinical and biological parameters, including serum IL-6 levels, of the intervention population against controls of the same pandemic outbreak (using a propensity score) to search for markers that identify the best candidates for the treatment with subcutaneous IL-6R inhibitors and to attempt an approximation in the temporal frame of the "window of opportunity" TRIAL DESIGN: SARCOVID is an investigator-initiated single center randomised proof of concept study.
Patients treated at the Hospital Universitario La Princesa, Madrid, Spain requiring hospitalisation will be consecutively recruited, meeting all inclusion criteria and none of the exclusion criteria Inclusion criteria a. Age >18, <80 years old b. COVID-19 infection documented by a positive RT-PCR test or, in absence of a RT-PCR positive test, case definition of COVID 19 infection/pneumonia as per local protocol and the presence of a positive serologic test (IgM/IgA by ELISA) c. Documented interstitial pneumonia requiring admission and at least two of the following parameters: 1) Fever ≥ 37.8°C (tympanic) 2) IL-6 in serum ≥ 25 pg/mL (in the absence of a previous dose of prednisone or equivalent> 1 mg / kg) or PCR> 5mg/dL 3) Lymphocytes <600 cells/mm
4) Ferritin> 300 μg/L that doubles in 24 hours 5) Ferritin> 600 μg/L in the first determination and LDH> 250 U/L 6) D-dimer (> 1 mg/L) d. Informed verbal consent or requested under urgent conditions, documented in the electronic medical record. Exclusion criteria a. Patients who require mechanical ventilation at the time of inclusion. b. AST / ALT values > 5 folds the ULN. c. Absolute neutrophil count below 500 cells/mm
d. Absolute platelet count below 50,000 cells/mm
e. Documented sepsis or high suspicion of superimposed infection by pathogens other than COVID-19. f. Presence of comorbidities that can likely lead to an unfavourable result according to clinical judgment. g. Complicated diverticulitis or intestinal perforation. h. Current skin infection (eg, uncontrolled dermopiodermitis). i. Immunosuppressive anti-rejection therapy. j. Pregnancy or lactation. k. Previous treatment with tocilizumab or sarilumab. l. Patients participating in another clinical trial for SARS-CoV-2 infection. m. Patients with known hypersensitivity or contraindication to sarilumab or excipients.
The intervention group, sarilumab plus standard of care, will receive 400 mg single dose treatment with Sarilumab (Kevzara), 2 subcutaneous injections 200mg each in a pre-filled syringe. Treatment with drugs or procedures in routine clinical practice that the clinician responsible for the patient deems necessary is allowed. The control group will receive drugs or procedures in routine clinical practice according to the best standard of care as per local protocol.
Primary Outcome Measures 1. Mean change in clinical status assessment using the 7-point ordinal scale at day 7 after randomisation compared to baseline (Score ranges 1-7) 1. Death; 2. Hospitalised, requiring invasive mechanical ventilation or extracorporeal membrane oxygenation (ECMO); 3. Hospitalised, requiring non-invasive ventilation or high flow oxygen devices; 4. Hospitalised, requiring supplemental oxygen; 5. Hospitalised, not requiring supplemental oxygen - but in need of ongoing medical care (COVID-19 related or otherwise) 6. Hospitalised, not requiring supplemental oxygen - no longer requires ongoing medical care (independent) 7. Not hospitalised 2. Duration of hospitalisation: Days from the date of enrolment to the date of discharge 3. Number of deaths at the end of study RANDOMISATION: Randomisation to treatment arms sarilumab plus standard of care or standard of care in a 2:1 ratio will be performed by the Clinical Research and Clinical Trials Unit (CRCTU) at the Hospital using a table of random numbers, an internet-based randomisation tool. After checking that all inclusion criteria are met and none of the exclusion criteria, CRCTU will communicate the recruiting investigator the assigned treatment.
This study is unblinded.
30 patients treated by COVID-19 infection who require hospitalisation: 20 will receive sarilumab plus Standard of Care and 10 will receive Standard of Care.
The Protocol version number is 2, as of 6
April 2020, with amendment 1, as of 7
May 2020. The recruitment is ongoing. Recruitment started on April 13
2020 and is anticipated to be completed by November 2020.
This trial was first registered in the European Union Clinical Trials Register on 4 April 2020, EudraCT Number 2020-001634-36 . Then, posted on ClinicalTrials.gov on 22 April 2020, Identifier: NCT04357808 .
The full protocol is attached as an additional file, accessible from the Trials website (Additional file 1). In the interest in expediting dissemination of this material, the familiar formatting has been eliminated; this Letter serves as a summary of the key elements of the full protocol. The study protocol has been reported in accordance with the International Council Harmonization guidelines: https://www.ich.org/page/efficacy-guidelines .
Gender-specific consequences after HCV eradication are unexplored. MicroRNAs (miRNAs) play a crucial role in the immune response against viral infections. However, few have highlighted miRNA role in ...sex-biased disease or therapy response. We aim to assess gender differences reflected in the miRNA expression of HIV/HCV-coinfected patients who achieve sustained virological response (SVR) with direct acting antivirals (DAAs). We conducted a prospective study of miRNA expression in PBMCs from 28 chronic HIV/HCV-coinfected patients (HIV/HCV) at baseline and after achieving SVR with DAAs. Sixteen HIV-monoinfected patients (HIV) and 36 healthy controls (HC) were used as controls. Identification of significant differentially expressed (SDE) miRNAs was performed with generalized linear model and mixed GLMs. We also explored putative dysregulated biological pathways. At baseline, the HIV/HCV patients showed differences in the miRNA profile concerning the HIV group (165 and 102 SDE miRNAs for males and females, respectively). Gender-stratified analysis of HIV/HCV group at baseline versus at SVR achievement showed higher differences in males (80 SDE miRNAs) than in females (55 SDE miRNAs). After SVR, HIV/HCV group showed similar values to HIV individuals, especially in females (1 SDE miRNA). However, ten miRNAs in males remained dysregulated, which were mainly involved in cancer, fatty acid, and inflammatory pathways. Taken together, our results show gender-biased dysregulation in the miRNA expression profile of PBMCs after HCV eradication with DAAs. These differences were normalized in females, while miRNA profile and their target-related pathways in males lack of normalization, which may be related to a high-risk of developing liver-related complications.
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Phasins are intracellular polyhydroxyalkanoat4e (PHA)-associated proteins involved in the stabilization of these bacterial carbon storage granules. Despite its importance in PHA metabolism and ...regulation, only few reports have focused so far on the structure of these proteins. In this work we have investigated the structure and stability of the PhaF phasin from Pseudomonas putida KT2440, a protein that is involved in PHA granule stabilization and distribution to daughter cells upon cell division. A structural, three-dimensional model of the protein was built from homology modeling procedures and consensus secondary structure predictions. The model predicts that PhaF is an elongated protein, with a long, amphipathic N-terminal helix with PHA binding capacity, followed by a short leucine zipper involved in protein oligomerization and a superhelical C-terminal domain wrapped around the chromosomal DNA. Hydrodynamic, spectroscopical and thermodynamic experiments validated the model and confirmed both that free PhaF is a tetramer in solution and that most part of the protein is intrinsically disordered in the absence of its ligands. The results lay a molecular basis for the explanation of the biological role of PhaF and, along with an exhaustive analysis of phasin sequence databases, suggest that intrinsic disorder and oligomerization through coiled-coils may be a widespread mechanism among these proteins.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
A collection of repurposing drugs (Prestwick Chemical Library) containing 1200 compounds was screened to investigate the drugs' antimicrobial effects against planktonic cultures of the respiratory ...pathogen
. After four discrimination rounds, a set of seven compounds was finally selected, namely (i) clofilium tosylate; (ii) vanoxerine; (iii) mitoxantrone dihydrochloride; (iv) amiodarone hydrochloride; (v) tamoxifen citrate; (vi) terfenadine; and (vii) clomiphene citrate (Z, E). These molecules arrested pneumococcal growth in a liquid medium and induced a decrease in bacterial viability between 90.0% and 99.9% at 25 µM concentration, with minimal inhibitory concentrations (MICs) also in the micromolar range. Moreover, all compounds but mitoxantrone caused a remarkable increase in the permeability of the bacterial membrane and share a common, minimal chemical structure consisting of an aliphatic amine linked to a phenyl moiety via a short carbon/oxygen linker. These results open new possibilities to tackle pneumococcal disease through drug repositioning and provide clues for the design of novel membrane-targeted antimicrobials with a related chemical structure.
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