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1.
Antimicrob Agents Chemother ; 68(5): e0143923, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38591854

RESUMO

Phage therapy has (re)emerged as a serious possibility for combating multidrug-resistant bacterial infections, including those caused by vancomycin-resistant Enterococcus faecium strains. These opportunistic pathogens belong to a specific clonal complex 17, against which relatively few phages have been screened. We isolated a collection of 21 virulent phages growing on these vancomycin-resistant isolates. Each of these phages harbored a typical narrow plaquing host range, lysing at most 5 strains and covering together 10 strains of our panel of 14 clinical isolates. To enlarge the host spectrum of our phages, the Appelmans protocol was used. We mixed four out of our most complementary phages in a cocktail that we iteratively grew on eight naive strains from our panel, of which six were initially refractory to at least three of the combined phages. Fifteen successive passages permitted to significantly improve the lytic activity of the cocktail, from which phages with extended host ranges within the E. faecium species could be isolated. A single evolved phage able to kill up to 10 of the 14 initial E. faecium strains was obtained, and it barely infected nearby species. All evolved phages had acquired point mutations or a recombination event in the tail fiber genetic region, suggesting these genes might have driven phage evolution by contributing to their extended host spectra.


Assuntos
Bacteriófagos , Enterococcus faecium , Especificidade de Hospedeiro , Enterococos Resistentes à Vancomicina , Enterococcus faecium/efeitos dos fármacos , Bacteriófagos/genética , Enterococos Resistentes à Vancomicina/efeitos dos fármacos , Terapia por Fagos/métodos , Infecções por Bactérias Gram-Positivas/microbiologia , Resistência a Vancomicina , Vancomicina/farmacologia , Humanos , Antibacterianos/farmacologia
2.
ISME J ; 18(1)2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38366192

RESUMO

CRISPR-Cas systems are defense mechanisms against phages and other nucleic acids that invade bacteria and archaea. In Escherichia coli, it is generally accepted that CRISPR-Cas systems are inactive in laboratory conditions due to a transcriptional repressor. In natural isolates, it has been shown that CRISPR arrays remain stable over the years and that most spacer targets (protospacers) remain unknown. Here, we re-examine CRISPR arrays in natural E. coli isolates and investigate viral and bacterial genomes for spacer targets using a bioinformatics approach coupled to a unique biological dataset. We first sequenced the CRISPR1 array of 1769 E. coli isolates from the fecal samples of 639 children obtained during their first year of life. We built a network with edges between isolates that reflect the number of shared spacers. The isolates grouped into 34 modules. A search for matching spacers in bacterial genomes showed that E. coli spacers almost exclusively target prophages. While we found instances of self-targeting spacers, those involving a prophage and a spacer within the same bacterial genome were rare. The extensive search for matching spacers also expanded the library of known E. coli protospacers to 60%. Altogether, these results favor the concept that E. coli's CRISPR-Cas is an antiprophage system and highlight the importance of reconsidering the criteria use to deem CRISPR-Cas systems active.


Assuntos
Bacteriófagos , Prófagos , Criança , Humanos , Prófagos/genética , Escherichia coli/genética , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Bacteriófagos/genética , Genoma Bacteriano , Sistemas CRISPR-Cas
4.
Nat Med ; 30(1): 138-148, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38102298

RESUMO

Bacteriophage (also known as phage) communities that inhabit the gut have a major effect on the structure and functioning of bacterial populations, but their roles and association with health and disease in early life remain unknown. Here, we analyze the gut virome of 647 children aged 1 year from the Copenhagen Prospective Studies on Asthma in Childhood2010 (COPSAC2010) mother-child cohort, all deeply phenotyped from birth and with longitudinally assessed asthma diagnoses. Specific temperate gut phage taxa were found to be associated with later development of asthma. In particular, the joint abundances of 19 caudoviral families were found to significantly contribute to this association. Combining the asthma-associated virome and bacteriome signatures had additive effects on asthma risk, implying an independent virome-asthma association. Moreover, the virome-associated asthma risk was modulated by the host TLR9 rs187084 gene variant, suggesting a direct interaction between phages and the host immune system. Further studies will elucidate whether phages, alongside bacteria and host genetics, can be used as preclinical biomarkers for asthma.


Assuntos
Asma , Bacteriófagos , Lactente , Humanos , Pré-Escolar , Viroma , Estudos Prospectivos , Bacteriófagos/genética , Asma/epidemiologia , Asma/genética , Bactérias/genética
5.
FEMS Microbiol Lett ; 3702023 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-37791400

RESUMO

What we know about Tubulavirales, i.e. filamentous phages, essentially comes from Gram-negative-infecting Inoviridae. However, metagenomics recently suggests filamentous phages are much more widespread and diverse. Here, we report the complete sequence and functional annotation of CAK1, a 6.6 kb filamentous phage that was shown to chronically infect Clostridium beijerinckii 30 years ago and only represents the second filamentous phage cultivated on a Gram-positive bacterium. CAK1 has a typical filamentous phage modular genome with no homologs in databases and we were interested to compare it with a pig gut filamentous phage metagenomics dataset that we previously assembled and for which many filamentous phages were predicted to infect Clostridium species by bioinformatics means. CAK1 is distantly related to nine of these sequences, two of which have been predicted as Clostridium-associated. In itself, this small cluster of CAK1-connected sequences sheds light on the diversity of filamentous phages that putatively infect Clostridium species, and probably many other Gram-positive genera.


Assuntos
Bacteriófagos , Vírus , Animais , Suínos , Vírus/genética , Genoma , Clostridium/genética , Biologia Computacional , Bacteriófagos/genética , Genoma Viral , Filogenia
6.
RSC Adv ; 13(15): 10051-10067, 2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-37006376

RESUMO

The current study presents for the first time the synthesis of a new 2:1-[α/aza]-pseudopeptide series possessing charged amino acids (i.e., lysine) and aims at studying the influences of chirality, backbone length, and the nature of the lysine side chains on the conformation of the 2:1-[α/aza]-oligomers in solution using NMR, FTIR spectroscopy and molecular dynamic calculations. The spectroscopic results emphasized the conservation of the ß-turn conformation adopted by the trimers regardless of the chirality which demonstrated a noticeable effect on the conformation of homochiral hexamer (8c) compared with the hetero-analogue (8d). The molecular dynamic calculations predicted that the chirality and the side chain of the lysine residues caused a little distortion from the classical ß-turn conformation in the case of short trimer sequences (7c and 7d), while the chirality and the backbone length exerted more distortion on the ß-turn adopted by the longer hexamer sequences (8c and 8d). The large disturbance in hexamers from classical ß-turn was attributed to increasing the flexibility and the possibility of molecules to adopt a more energetically favorable conformation stabilized by non-classical ß-turn intramolecular hydrogen bonds. Thus, alternating d- and l-lysine amino acids in the 2:1-[α/aza]-hexamer (8d) decreases the high steric hindrance between the lysine side chains, as in the homo analogue (8c), and the distortion is less recognized. Finally, short sequences of aza-pseudopeptides containing lysine residues improve CO2 separation when used as additives in Pebax® 1074 membranes. The best membrane performances were obtained with a pseudopeptidic dimer as an additive (6b'; deprotected lysine side chain), with an increase in both ideal selectivity α CO2/N2 (from 42.8 to 47.6) and CO2 permeability (from 132 to 148 Barrer) compared to the virgin Pebax® 1074 membrane.

7.
Nat Microbiol ; 8(5): 986-998, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37037943

RESUMO

The gut microbiome is shaped through infancy and impacts the maturation of the immune system, thus protecting against chronic disease later in life. Phages, or viruses that infect bacteria, modulate bacterial growth by lysis and lysogeny, with the latter being especially prominent in the infant gut. Viral metagenomes (viromes) are difficult to analyse because they span uncharted viral diversity, lacking marker genes and standardized detection methods. Here we systematically resolved the viral diversity in faecal viromes from 647 1-year-olds belonging to Copenhagen Prospective Studies on Asthma in Childhood 2010, an unselected Danish cohort of healthy mother-child pairs. By assembly and curation we uncovered 10,000 viral species from 248 virus family-level clades (VFCs). Most (232 VFCs) were previously unknown, belonging to the Caudoviricetes viral class. Hosts were determined for 79% of phage using clustered regularly interspaced short palindromic repeat spacers within bacterial metagenomes from the same children. Typical Bacteroides-infecting crAssphages were outnumbered by undescribed phage families infecting Clostridiales and Bifidobacterium. Phage lifestyles were conserved at the viral family level, with 33 virulent and 118 temperate phage families. Virulent phages were more abundant, while temperate ones were more prevalent and diverse. Together, the viral families found in this study expand existing phage taxonomy and provide a resource aiding future infant gut virome research.


Assuntos
Bacteriófagos , Microbioma Gastrointestinal , Lactente , Humanos , Estudos Prospectivos , Bacteriófagos/genética , Lisogenia , Fezes/microbiologia , Microbioma Gastrointestinal/genética , Bactérias/genética
8.
Proc Natl Acad Sci U S A ; 120(11): e2212121120, 2023 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-36881631

RESUMO

The most significant difference between bacteriophages functionally and ecologically is whether they are purely lytic (virulent) or temperate. Virulent phages can only be transmitted horizontally by infection, most commonly with the death of their hosts. Temperate phages can also be transmitted horizontally, but upon infection of susceptible bacteria, their genomes can be incorporated into that of their host's as a prophage and be transmitted vertically in the course of cell division by their lysogenic hosts. From what we know from studies with the temperate phage Lambda and other temperate phages, in laboratory culture, lysogenic bacteria are protected from killing by the phage coded for by their prophage by immunity; where upon infecting lysogens, the free temperate phage coded by their prophage is lost. Why are lysogens not only resistant but also immune to the phage coded by their prophage since immunity does not confer protection against virulent phages? To address this question, we used a mathematical model and performed experiments with temperate and virulent mutants of the phage Lambda in laboratory culture. Our models predict and experiments confirm that selection would favor the evolution of resistant and immune lysogens, particularly if the environment includes virulent phage that shares the same receptors as the temperate. To explore the validity and generality of this prediction, we examined 10 lysogenic Escherichia coli from natural populations. All 10 were capable of forming immune lysogens, but their original hosts were resistant to the phage coded by their prophage.


Assuntos
Bacteriófago lambda , Prófagos , Prófagos/genética , Bacteriófago lambda/genética , Livros , Lisogenia , Escherichia coli
9.
PLoS Pathog ; 19(2): e1011127, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36730457

RESUMO

Adherent-invasive Escherichia coli (AIEC) strains are frequently recovered from stools of patients with dysbiotic microbiota. They have remarkable properties of adherence to the intestinal epithelium, and survive better than other E. coli in macrophages. The best studied of these AIEC is probably strain LF82, which was isolated from a Crohn's disease patient. This strain contains five complete prophages, which have not been studied until now. We undertook their analysis, both in vitro and inside macrophages, and show that all of them form virions. The Gally prophage is by far the most active, generating spontaneously over 108 viral particles per mL of culture supernatants in vitro, more than 100-fold higher than the other phages. Gally is also over-induced after a genotoxic stress generated by ciprofloxacin and trimethoprim. However, upon macrophage infection, a genotoxic environment, this over-induction is not observed. Analysis of the transcriptome and key steps of its lytic cycle in macrophages suggests that the excision of the Gally prophage continues to be repressed in macrophages. We conclude that strain LF82 has evolved an efficient way to block the lytic cycle of its most active prophage upon macrophage infection, which may participate to its good survival in macrophages.


Assuntos
Bacteriófagos , Infecções por Escherichia coli , Humanos , Escherichia coli , Macrófagos , Mucosa Intestinal , Aderência Bacteriana
10.
Microbiol Spectr ; 11(1): e0421122, 2023 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-36625667

RESUMO

Streptococcus pyogenes prophage Φ1207.3 (formerly Tn1207.3) carries the mef(A)-msr(D) resistance genes, responsible for type M macrolide resistance. To investigate if Φ1207.3 is a functional bacteriophage, we transferred the element from the original S. pyogenes host in a prophage-free and competence-deficient S. pneumoniae strain. Pneumococcal cultures of the Φ1207.3-carrying lysogen were treated with mitomycin C to assess if Φ1207.3 enters the lytic cycle. Mitomycin C induced a limited phage burst and a growth impairment, resulting in early entrance into the stationary phase. To determine if Φ1207.3 is able to produce mature phage particles, we prepared concentrated supernatants recovered from a mitomycin C-induced pneumococcal culture by sequential centrifugation and ultracentrifugation steps. Negative-staining transmission electron microscopy (TEM) of supernatants revealed the presence of phage particles with an icosahedral, electron-dense capsid and a long, noncontractile tail, typical of a siphovirus. Quantification of Φ1207.3 was performed by quantitative PCR (qPCR) and semiquantitatively by TEM. PCR quantified 3.34 × 104 and 6.06 × 104 excised forms of phage genome per milliliter of supernatant obtained from the untreated and mitomycin C-treated cultures, respectively. By TEM, we estimated 3.02 × 103 and 7.68 × 103 phage particles per milliliter of supernatant. The phage preparations of Φ1207.3 infected and lysogenized pneumococcal recipient strains at a frequency of 7.5 × 10-6 lysogens/recipient but did not show sufficient lytic activity to form plaques. Phage lysogenization efficiently occurred after 30 min of contact of the phages with the recipient cells and required a minimum of 103 phage particles. IMPORTANCE Bacteriophages play an important role in bacterial physiology and genome evolution. The widespread use of genome sequencing revealed that bacterial genomes can contain several different integrated temperate bacteriophages, which can constitute up to 20% of the genome. Most of these bacteriophages are only predicted in silico and are never shown to be functional. In fact, it is often difficult to induce the lytic cycle of temperate bacteriophages. In this work, we show that Φ1207.3, a peculiar bacteriophage originally from Streptococcus pyogenes, which can lysogenize different streptococci and carries the macrolide resistance mef(A)-msr(D) gene pair, is capable of producing mature virions, but only at a low level, while not being able to produce plaques. This temperate phage is probably a partially functional phage, which seems to have lost lytic characteristics to specialize in lysogenization. While we are not used to conceiving phages separately from lysis, this behavior could actually be more frequent than expected.


Assuntos
Bacteriófagos , Bacteriófagos/genética , Antibacterianos/farmacologia , Streptococcus pyogenes , Macrolídeos/farmacologia , Mitomicina/farmacologia , Farmacorresistência Bacteriana/genética , Prófagos/genética
11.
J Phys Chem B ; 126(37): 7159-7165, 2022 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-36099394

RESUMO

The electric field gradient tensor (considered here at the level of a nitrogen nucleus) can be described by two parameters: the largest element in the (X,Y,Z) principal axis system, denoted by VZZ (leading to the nuclear quadrupole coupling), and the asymmetry parameter η = (|VYY| - |VXX|)/|VZZ| with |VZZ| > |VYY| > |VXX|. The frequencies of the three nitrogen-14 nuclear quadrupole resonance (NQR) transitions depend on both parameters but, for sensitivity reasons, their determination may be especially difficult and time consuming. For a partly rigid NH grouping with a labile proton, water nuclear magnetic resonance (NMR) relaxometry curves may exhibit these three transitions (dubbed quadrupolar dips or quadrupole relaxation enhancement (QRE)), provided that the NH grouping belongs to a moiety possessing a sufficient degree of ordering. Their line shape leads to the correlation time describing mainly the motion of the NH grouping (the proton of which being in exchange with water protons), and their amplitude can be interpreted in terms of an effective NH distance. This approach is applied to a hydrogel, where separate NQR lines are observed for the different types of water existing in this system. Furthermore, the analysis of experimental data allows one to determine the nuclear quadrupole coupling in the protonated and deprotonated forms of this molecular moiety involving a labile NH grouping.


Assuntos
Prótons , Água , Hidrogéis , Espectroscopia de Ressonância Magnética , Nitrogênio/química
12.
Mol Microbiol ; 118(5): 494-502, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36164818

RESUMO

Compared to bacteria of the gut microbiota, bacteriophages are still poorly characterised, and their physiological importance is far less known. Temperate phages are probably a major actor in the gut, as it is estimated that 80% of intestinal bacteria are lysogens, meaning that they are carrying prophages. In addition, prophage induction rates are higher in the gut than in vitro. However, studies on the signals leading to prophage induction have essentially focused on genotoxic agents with poor relevance for this environment. In this review, we sum up recent findings about signals able to trigger prophage induction in the gut. Three categories of signals are at play: those originating from interactions between intestinal microbes, those from the human or animal host physiology and those from external intakes. These recent results highlight the diversity of factors influencing prophage induction in the gut, and start to unveil ways by which microbiota composition may be modulated.


Assuntos
Bacteriófagos , Microbioma Gastrointestinal , Animais , Humanos , Lisogenia , Ativação Viral/fisiologia , Prófagos/genética , Bacteriófagos/genética
13.
Biomedicines ; 10(8)2022 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-35892674

RESUMO

Pemphigus is a life-threatening auto-immune blistering disease of the skin and mucous membrane that is caused by the production of auto-antibodies (auto-Abs) directed against adhesion proteins: desmoglein 1 and 3. We demonstrated in the "Ritux3" trial, the high efficacy of rituximab, an anti-CD20 recombinant monoclonal antibody, as the first-line treatment for pemphigus. However, 25% of patients relapsed during the six-month period after rituximab treatment. These early relapses were associated with a lower decrease in anti-desmoglein auto-Abs after the initial cycle of rituximab. The N-glycosylation of immunoglobulin-G (IgG) can affect their affinity for Fc receptors and their serum half-life. We hypothesized that the extended half-life of Abs could be related to modifications of IgG N-glycans. The IgG N-glycome from pemphigus patients and its evolution under rituximab treatment were analyzed. Pemphigus patients presented a different IgG N-glycome than healthy donors, with less galactosylated, sialylated N-glycans, as well as a lower level of N-glycans bearing an additional N-acetylglucosamine. IgG N-glycome from patients who achieved clinical remission was not different to the one observed at baseline. Moreover, our study did not identify the N-glycans profile as discriminating between relapsing and non-relapsing patients. We report that pemphigus patients present a specific IgG N-glycome. The changes observed in these patients could be a biomarker of autoimmunity susceptibility rather than a sign of inflammation.

14.
Viruses ; 14(8)2022 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-35893685

RESUMO

Smear-ripened cheeses host complex microbial communities that play a crucial role in the ripening process. Although bacteriophages have been frequently isolated from dairy products, their diversity and ecological role in such this type of cheese remain underexplored. In order to fill this gap, the main objective of this study was to isolate and characterize bacteriophages from the rind of a smear-ripened cheese. Thus, viral particles extracted from the cheese rind were tested through a spot assay against a collection of bacteria isolated from the same cheese and identified by sequencing the full-length small subunit ribosomal RNA gene. In total, five virulent bacteriophages infecting Brevibacterium aurantiacum, Glutamicibacter arilaitensis, Leuconostoc falkenbergense and Psychrobacter aquimaris species were obtained. All exhibit a narrow host range, being only able to infect a few cheese-rind isolates within the same species. The complete genome of each phage was sequenced using both Nanopore and Illumina technologies, assembled and annotated. A sequence comparison with known phages revealed that four of them may represent at least new genera. The distribution of the five virulent phages into the dairy-plant environment was also investigated by PCR, and three potential reservoirs were identified. This work provides new knowledge on the cheese rind viral community and an overview of the distribution of phages within a cheese factory.


Assuntos
Bacteriófagos , Queijo , Microbiota , Bactérias/genética , Bacteriófagos/genética , Microbiota/genética , Análise de Sequência de DNA
15.
Front Immunol ; 13: 849790, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35371083

RESUMO

Introduction: We studied the distribution and in vitro pathogenicity of anti-DSG3 IgG subclasses during the course of pemphigus vulgaris (PV). Methods: We longitudinally studied the distribution of anti-DSG3 IgG subclasses (before versus after treatment) in sera from PV patients, using an addressable-laser bead immunoassay (ALBIA). The in vitro pathogenicity of corresponding sera was tested using keratinocyte dissociation and immunofluorescence assays. Results: Sixty-five sera were assessed at baseline (33 from patients treated with rituximab and 32 with corticosteroids). Sixty-three percent of these baseline sera contained 2 or more anti-DSG3 IgG subclasses versus 35.7% of sera from patients in complete remission (CR) and 75.0% of sera from patients with persistent disease activity after treatment. IgG4 was the most frequently detected anti-DSG3 IgG subclass, both in patients with disease activity and in those in CR. The presence of three or more anti-DSG3 IgG subclasses was predictive of relapse, in particular when it included IgG3, with a positive predictive value of 62.5% and a negative predictive value of 92%. While anti-DSG3 IgG4 Abs from sera collected before treatment were most often pathogenic, anti-DSG3 IgG4 from sera collected after treatment were pathogenic only after adjusting their titer to the one measured before treatment. The IgG3 fraction containing anti-DSG3 Abs also had an in vitro pathogenic effect. The disappearance of the pathogenic effect of some sera after removal of anti-DSG3 IgG3 suggested an additional effect of this IgG subclass. Conclusion: The serum levels and number of anti-DSG3 IgG subclasses drive the pathogenic effect of pemphigus sera and may predict the occurrence of relapses.


Assuntos
Pênfigo , Autoanticorpos , Desmogleína 3 , Humanos , Imunoglobulina G , Pênfigo/tratamento farmacológico , Pênfigo/patologia , Recidiva , Rituximab/uso terapêutico
16.
Nanoscale ; 14(13): 4908-4921, 2022 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-35319034

RESUMO

Over the last twenty years, low-molecular weight gelators and, in particular, peptide-based hydrogels, have drawn great attention from scientists thanks to both their inherent advantages in terms of properties and their high modularity (e.g., number and nature of the amino acids). These supramolecular hydrogels originate from specific peptide self-assembly processes that can be driven, modulated and optimized via specific chemical modifications brought to the peptide sequence. Among them, the incorporation of nucleobases, another class of biomolecules well-known for their abilities to self-assemble, has recently appeared as a new promising and burgeoning approach to finely design supramolecular hydrogels. In this minireview, we would like to highlight the interest, high potential, applications and perspectives of these innovative and emerging low-molecular weight nucleopeptide-based hydrogels.


Assuntos
Hidrogéis , Peptídeos , Sequência de Aminoácidos , Aminoácidos/química , Hidrogéis/química , Peso Molecular , Peptídeos/química
17.
Psychol Trauma ; 14(S1): S41-S49, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34472942

RESUMO

OBJECTIVE: Child sexual abuse (CSA) is associated with long-term negative consequences in adolescents, but some survivors display resilience. The purpose of this study was to delineate profiles of adaptation in adolescent victims of CSA and to examine their associations with individual and environmental-systemic protective factors. METHOD: As part of a population-based survey, 8,230 high school students were questioned about CSA and completed measures assessing a host of protective factors and indicators of positive adaptation across 5 domains: self-perception, academic success, mental health, health risk behaviors and romantic relationships. RESULTS: Using a latent class analysis, a best fitting model of 4 classes was identified. This model included a reference group of nonsexually abused teenagers and 3 classes characterizing survivors of CSA: Resilient profile (33% of youth), Externalized profile (34% of youth) and Internalized profile (33% of youth). Sexually abused youth assigned to the Resilient profile were similar to nonsexually abused youth in terms of self-esteem, academic performance, absence of clinical levels of psychological distress and dating violence. Despite experiencing CSA of comparable severity, youth in the Resilient profile reported more optimism and were less likely to rely on avoidant or emotional strategies to cope with difficulties and more likely to report high maternal and paternal support. CONCLUSIONS: Findings highlight the utility of a person-oriented approach to enhance our understanding of the diversity of adaptation profiles in youth victims of CSA. Results also underscore the importance of tailoring intervention efforts to efficiently tackle the diverse needs of teen victims of CSA. (PsycInfo Database Record (c) 2022 APA, all rights reserved).


Assuntos
Abuso Sexual na Infância , Maus-Tratos Infantis , Vítimas de Crime , Adaptação Psicológica , Adolescente , Criança , Maus-Tratos Infantis/psicologia , Abuso Sexual na Infância/psicologia , Vítimas de Crime/psicologia , Humanos , Autoimagem , Estudantes/psicologia , Sobreviventes/psicologia
18.
Biomedicines ; 9(10)2021 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-34680528

RESUMO

Pemphigus vulgaris is an autoimmune disease that occurs due to pathogenic autoantibodies that recognize the following epidermal adhesion proteins: desmogleins. Systemic corticosteroids usually decrease the titers of anti-desmoglein autoantibodies and improve patients' conditions. Since modifications of IgG N-glycosylation have been described in some autoimmune diseases, we hypothesized that changes in the pathogenic activity of pemphigus IgG could be related to changes in their N-glycosylation profile. The purpose of this study was to assess, longitudinally, the pathogenicity of pemphigus serum IgG and their N-glycosylation profile during phases of disease activity and clinical remission. The pathogenic activity of serum IgG was measured in vitro on immortalized keratinocytes, by immunofluorescence and dissociation assays, and IgG N-glycans were analyzed by mass spectrometry. We showed (i) a correlation between pemphigus clinical activity and the pathogenicity of serum IgG at baseline and at month 6, while the persistence of the in vitro pathogenic activity of IgG during its evolution, even in patients in clinical remission, seemed to be predictive of relapse; (ii) that modifications of the N-glycan structure were altered the in vitro pathogenicity of patients' autoantibodies; (iii) that the pathogenic properties of pemphigus IgG did not appear to be related to the disparity in IgG N-glycans during the course of pemphigus.

19.
BMC Palliat Care ; 20(1): 156, 2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-34645445

RESUMO

BACKGROUND: Despite increasing use of telemedicine in the field of palliative care, studies about the best circumstances and processes where it could replace face-to-face interaction are lacking. This study aimed to: (1) identify situations that are most amenable to the use of telemedicine for the provision of palliative care to patients in nursing homes; and (2) understand how telemedicine could best be integrated into the routine practice of mobile palliative care teams. METHODS: A qualitative study based on semi-structured focus groups (n = 7) with professionals (n = 33) working in mobile palliative care teams in France. RESULTS: Between June and July 2019, 7 mobile palliative care teams participated in one focus group each. Using thematic analysis, we found that telemedicine use in palliative care is about navigating between usual and new practices. Several influencing factors also emerged, which influence the use of telemedicine for palliative care, depending on the situation. Finally, we built a use-case model of palliative care to help mobile palliative care teams identify circumstances where telemedicine could be useful, or not. CONCLUSIONS: The potential utility of telemedicine for delivering palliative care in nursing homes largely depends on the motive for calling on the mobile palliative care team. Requests regarding symptoms may be particularly amenable to telemedicine, whereas psycho-social distress may not. Further studies are warranted to assess the impact of influencing factors on real-life palliative care practices. Telemedicine could nonetheless be a useful addition to the mobile palliative care teams' armamentarium.


Assuntos
Enfermagem de Cuidados Paliativos na Terminalidade da Vida , Telemedicina , Humanos , Casas de Saúde , Cuidados Paliativos , Pesquisa Qualitativa
20.
Microorganisms ; 9(9)2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-34576747

RESUMO

The bacterial consumption of viruses not been reported on as of yet even though bacteria feed on almost anything. Viruses are widely distributed but have no acknowledged active biocontrol. Viral biomass undoubtedly reintegrates trophic cycles; however, the mechanisms of this phase still remain unknown. 13C-labelled T4 phages monitor the increase of the density of the bacterial DNA concomitant with the decrease of plaque forming units. We used 12C T4 phages as a control. T4 phage disappearance in wastewater sludge was found to occur mainly through predation by Aeromonadacea. Phage consumption also favours significant in situ bacterial growth. Furthermore, an isolated strain of Aeromonas was observed to grow on T4 phages as sole the source of carbon, nitrogen, and phosphorus. Bacterial species are capable of consuming bacteriophages in situ, which is likely a widespread and underestimated type of biocontrol. This assay is anticipated as a starting point for harnessing the bacterial potential in limiting the diffusion of harmful viruses within environments such as in the gut or in water.

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