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1.
Life Sci Alliance ; 7(8)2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38834194

RESUMO

Vinculin is a cytoskeletal linker strengthening cell adhesion. The Shigella IpaA invasion effector binds to vinculin to promote vinculin supra-activation associated with head-domain-mediated oligomerization. Our study investigates the impact of mutations of vinculin D1D2 subdomains' residues predicted to interact with IpaA VBS3. These mutations affected the rate of D1D2 trimer formation with distinct effects on monomer disappearance, consistent with structural modeling of a closed and open D1D2 conformer induced by IpaA. Notably, mutations targeting the closed D1D2 conformer significantly reduced Shigella invasion of host cells as opposed to mutations targeting the open D1D2 conformer and later stages of vinculin head-domain oligomerization. In contrast, all mutations affected the formation of focal adhesions (FAs), supporting the involvement of vinculin supra-activation in this process. Our findings suggest that IpaA-induced vinculin supra-activation primarily reinforces matrix adhesion in infected cells, rather than promoting bacterial invasion. Consistently, shear stress studies pointed to a key role for IpaA-induced vinculin supra-activation in accelerating and strengthening cell-matrix adhesion.


Assuntos
Adesão Celular , Adesões Focais , Vinculina , Vinculina/metabolismo , Vinculina/genética , Humanos , Adesões Focais/metabolismo , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Mutação , Interações Hospedeiro-Patógeno , Células HeLa , Ligação Proteica , Shigella/metabolismo , Shigella/genética , Antígenos de Bactérias/metabolismo , Antígenos de Bactérias/genética , Disenteria Bacilar/microbiologia , Disenteria Bacilar/metabolismo
2.
Sci Rep ; 14(1): 2657, 2024 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-38302552

RESUMO

Bacteriophage therapy is one potential strategy to treat antimicrobial resistant or persistent bacterial infections, and the year 2021 marked the centennial of Felix d'Hérelle's first publication on the clinical applications of phages. At the Center for Phage Biology & Therapy at Yale University, a preparatory modular approach has been established to offer safe and potent phages for single-patient investigational new drug applications while recognizing the time constraints imposed by infection(s). This study provides a practical walkthrough of the pipeline with an Autographiviridae phage targeting Pseudomonas aeruginosa (phage vB_PaeA_SB, abbreviated to ΦSB). Notably, a thorough phage characterization and the evolutionary selection pressure exerted on bacteria by phages, analogous to antibiotics, are incorporated into the pipeline.


Assuntos
Bacteriófagos , Terapia por Fagos , Infecções por Pseudomonas , Fagos de Pseudomonas , Humanos , Pseudomonas aeruginosa , Universidades , Fagos de Pseudomonas/genética , Infecções por Pseudomonas/terapia , Infecções por Pseudomonas/microbiologia
3.
ACS Appl Mater Interfaces ; 16(5): 5337-5354, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38284988

RESUMO

The use of electrically conductive polymers (CPs) in the development of electronic devices has attracted significant interest due to their unique intrinsic properties, which result from the synergistic combination of physicochemical properties in conventional polymers with the electronic properties of metals or semiconductors. Most conventional methods adopted for the fabrication of devices with nonplanar morphologies are still challenged by the poor ionic/electronic mobility of end products. Additive manufacturing (AM) brings about exciting prospects to the realm of CPs by enabling greater design freedom, more elaborate structures, quicker prototyping, relatively low cost, and more environmentally friendly electronic device creation. A growing variety of AM technologies are becoming available for three-dimensional (3D) printing of conductive devices, i.e., vat photopolymerization (VP), material extrusion (ME), powder bed fusion (PBF), material jetting (MJ), and lamination object manufacturing (LOM). In this review, we provide an overview of the recent research progress in the area of CPs developed for AM, which advances the design and development of future electronic devices. We consider different AM techniques, vis-à-vis, their development progress and respective challenges in printing CPs. We also discuss the material requirements and notable advances in 3D printing of CPs, as well as their potential electronic applications including wearable electronics, sensors, energy storage and conversion devices, etc. This review concludes with an outlook on AM of CPs.

4.
Expert Rev Anti Infect Ther ; 22(1-3): 19-23, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38217395

RESUMO

INTRODUCTION: Antimicrobial resistance in Latin America is a growing concern in both human and non-human animal populations. The economic burden that is likely to be imposed through increased resistance will cause further strains on public health systems and the population at large. AREAS COVERED: We propose the rapid adoption and implementation of phage therapy as a necessary addition to the medical arsenal to help mitigate antimicrobial resistance, with an emphasis on considering the potential benefits that highly biodiverse countries such as Ecuador may have on phage discovery. However, programs may count on limited government support and/or facilitation, which could slow progress. EXPERT OPINION: We highlight the need for educational campaigns to be implemented in parallel with the development of phage therapy programs, particularly to implement these novel treatments in rural and indigenous communities.


Assuntos
Anti-Infecciosos , Terapia por Fagos , Humanos , América Latina , Demografia , Países em Desenvolvimento
6.
Polymers (Basel) ; 15(21)2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37959886

RESUMO

Self-healing polymers have received widespread attention due to their ability to repair damage autonomously and increase material stability, reliability, and economy. However, the processability of self-healing materials has yet to be studied, limiting the application of rich self-healing mechanisms. Additive manufacturing effectively improves the shortcomings of conventional processing while increasing production speed, accuracy, and complexity, offering great promise for self-healing polymer applications. This article summarizes the current self-healing mechanisms of self-healing polymers and their corresponding additive manufacturing methods, and provides an outlook on future developments in the field.

7.
Phage (New Rochelle) ; 4(3): 141-149, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37841386

RESUMO

Background: The antimicrobial resistance catastrophe is a growing global health threat and predicted to be worse in developing countries. Phages for Global Health (PGH) is training scientists in these regions to isolate relevant therapeutic phages for pathogenic bacteria within their locality, and thus contributing to making phage technology universally available. Materials and Methods: During the inaugural PGH workshop in East Africa, samples from Ugandan municipal sewage facilities were collected and two novel Escherichia coli lytic phages were isolated and characterized. Results: The phages, UP19 (capsid diameter ∼100 nm, contractile tail ∼120/20 nm) and UP30 (capsid diameter ∼70 nm, noncontractile tail of ∼170/20 nm), lysed ∼82% and ∼36% of the 11 clinical isolates examined, respectively. The genomes of UP19 (171.402 kb, 282 CDS) and UP30 (49.834 kb, 75 CDS) closely match the genera Dhakavirus and Tunavirus, respectively. Conclusion: The phages isolated have therapeutic potential for further development against E. coli infections.

8.
Healthc Policy ; 19(1): 81-98, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37695710

RESUMO

Introduction: World Health Organization (WHO) guidelines recommend countries set quality plans for their health systems with clear priorities, indicators and targets. This paper examines whether Canada's federal, provincial and territorial governments are applying these principles. Methods: We evaluated plans from 2010 to 2019 for 14 ministries of health and four health authorities in provinces with a single authority against a rubric that considered the existence of indicators, baselines, targets, time frames and progress reports. Results: Ratings ranged from A+ to F with a median B/B-. Most jurisdictions had indicators, but only five of 18 jurisdictions had clear baselines, numeric targets and time frames. Irregularities were observed, such as vague indicators; setting goals to "improve" without targets; announcing targets only after plans had ended; setting minimal targets; removing targets after missing them previously; or inappropriate characterization of progress. Discussion: Most Canadian governments are reluctant to set quality targets. We speculate there may be fear of criticism if targets are missed. However, several jurisdictions had clear, ambitious plans that may serve as examples for others.


Assuntos
Governo , Qualidade da Assistência à Saúde , Humanos , Canadá
9.
IDCases ; 33: e01854, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37577050

RESUMO

Chronic prosthetic joint infections are difficult to treat without conducting revision surgery because conventional antibiotics cannot eradicate bacteria that reside in biofilms. Consequently, novel therapeutics are needed to help treat prosthetic joint infections with one being bacteriophage therapy given its innate biofilm activity. Herein a sixty-nine-year-old man with a recalcitrant Enterococcus faecalis prosthetic joint infection is discussed. The patient was successfully treated with personalized bacteriophage therapy and after two years of follow up he has not had a clinical recurrence. Overall, this case report supports that bacteriophage therapy for prosthetic joint infections has promise to reduce the morbidity that is associated with current treatments. However, more research is needed to assess whether this therapeutic is helping eradicate infections or if it is making bacteria less pathogenic. This is an important point which will need to be evaluated as this therapeutic continues to be developed for all infections.

10.
Front Endocrinol (Lausanne) ; 14: 1211696, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37497346

RESUMO

Background: In terms of assessing obesity-associated risk, quantification of visceral adipose tissue (VAT) has become increasingly important in risk assessment for cardiovascular and metabolic diseases. However, differences exist in the accuracy of various modalities, with a lack of up-to-date comparison with three-dimensional whole volume assessment. Aims: Using CT or MRI three-dimensional whole volume VAT as a reference, we evaluated the correlation of various commonly used modalities and techniques namely body impedance analysis (BIA), dual-energy x-ray absorptiometry (DXA) as well as single slice CT to establish how these methods compare. Methods: We designed the study in two parts. First, we performed an intra-individual comparison of the 4558 participants from the UK Biobank cohorts with matching data of MRI abdominal body composition, DXA with VAT estimation, and BIA. Second, we evaluated 174 CT scans from the publicly available dataset to assess the correlation of the commonly used single-slice technique compared to three-dimensional VAT volume. Results: Across the UK Biobank cohort, the DXA-derived VAT measurement correlated better (R2 0.94, p<0.0001) than BIA (R2 0.49, p<0.0001) with reference three-dimensional volume on MRI. However, DXA-derived VAT correlation was worse for participants with a BMI of < 20 (R2 = 0.62, p=0.0013). A commonly used single slice method on CT demonstrated a modest correlation (R2 between 0.51 - 0.64), with best values at L3- and L4 (R2 L3 = 0.63, p<0.0001; L4 = 0.64, p<0.0001) compared to reference three-dimensional volume. Combining multiple slices yielded a better correlation, with a strong correlation when L2-L3 levels were combined (R2 = 0.92, p<0.0001). Conclusion: When deployed at scale, DXA-derived VAT volume measurement shows excellent correlation with three-dimensional volume on MRI based on the UK Biobank cohort. Whereas a single slice CT technique demonstrated moderate correlation with three-dimensional volume on CT, with a stronger correlation achieved when multiple levels were combined.


Assuntos
Gordura Intra-Abdominal , Obesidade , Humanos , Gordura Intra-Abdominal/diagnóstico por imagem , Absorciometria de Fóton/métodos , Impedância Elétrica , Tomografia Computadorizada por Raios X
11.
J Investig Med High Impact Case Rep ; 11: 23247096231188243, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37515541

RESUMO

Cystic fibrosis (CF) is an important monogenic disease that affects more than 70 000 people worldwide. Defects of the CF transmembrane conductance regulator gene lead to dehydrated viscous secretions that result in chronic bacterial colonization. This leads to frequent recurrent lung infections called pulmonary exacerbations, lung inflammation, and resulting structural lung damage called bronchiectasis. Pseudomonas aeruginosa in particular is a common pathogen in persons with CF associated with increased pulmonary exacerbations, long-term lung function decline, and reduced survival. In addition, P. aeruginosa commonly develops antibiotic resistance and forms biofilms, making it difficult to treat. Here, we report the details of two patients with CF with pan-drug-resistant P. aeruginosa who were treated with a novel therapeutic strategy, bacteriophages. These cases highlight the need for further research and development of this treatment modality, including pediatric clinical trials.


Assuntos
Fibrose Cística , Terapia por Fagos , Infecções por Pseudomonas , Humanos , Criança , Fibrose Cística/terapia , Fibrose Cística/tratamento farmacológico , Pseudomonas aeruginosa , Infecções por Pseudomonas/complicações , Infecções por Pseudomonas/tratamento farmacológico , Pulmão
13.
Microbiol Resour Announc ; 12(7): e0010723, 2023 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-37272828

RESUMO

We present the structural and functional annotation of Escherichia coli bacteriophage 55, which has a genome length of 170,393 bp, with 219 predicted genes.

14.
Nat Commun ; 14(1): 3629, 2023 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-37369702

RESUMO

Bacteriophage therapy has been suggested as an alternative or complementary strategy for the treatment of multidrug resistant (MDR) bacterial infections. Here, we report the favourable clinical evolution of a 41-year-old male patient with a Kartagener syndrome complicated by a life-threatening chronic MDR Pseudomonas aeruginosa infection, who is treated successfully with iterative aerosolized phage treatments specifically directed against the patient's isolate. We follow the longitudinal evolution of both phage and bacterial loads during and after phage administration in respiratory samples. Phage titres in consecutive sputum samples indicate in patient phage replication. Phenotypic analysis and whole genome sequencing of sequential bacterial isolates reveals a clonal, but phenotypically diverse population of hypermutator strains. The MDR phenotype in the collected isolates is multifactorial and mainly due to spontaneous chromosomal mutations. All isolates recovered after phage treatment remain phage susceptible. These results demonstrate that clinically significant improvement is achievable by personalised phage therapy even in the absence of complete eradication of P. aeruginosa lung colonization.


Assuntos
Bacteriófagos , Pneumonia , Infecções por Pseudomonas , Masculino , Humanos , Bacteriófagos/genética , Pseudomonas aeruginosa , Pulmão , Farmacorresistência Bacteriana Múltipla , Infecção Persistente , Infecções por Pseudomonas/microbiologia , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico
15.
Clin Case Rep ; 11(6): e7600, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37351353

RESUMO

Key Clinical Message: Early identification and management of chronic invasive fungal rhinosinusitis (CIFRS) is key to optimizing outcomes. A missed diagnosis can result in permanent vision loss, chronic facial pain, or death. We present a case of CIFRS and literature review. Abstract: This case report presents a 56-year-old female with CIFRS involving orbital and facial complications. The patient experienced delayed diagnosis despite multiple ED visits for sinusitis with progressive facial pain and ocular deficits not alleviated with antibiotics, emphasizing the importance of early identification and maintaining high clinical suspicion for CIFRS. Prompt recognition, initiation of antifungal therapy, and aggressive surgical debridement were crucial for preventing disease progression and improving the patient's quality of life.

16.
Microbiol Resour Announc ; 12(6): e0010623, 2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37191527

RESUMO

We present the annotated genome sequence of Escherichia coli bacteriophage 107, a T4-like bacteriophage. Phage 107 has a genome length of 167,509 bp and 287 predicted genes.

17.
Emerg Med Clin North Am ; 41(2): 369-380, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37024170

RESUMO

Intimate partner violence and sexual violence represent significant public health challenges that carry many individual and societal costs. More than 1 in 3 women (35.6%) and more than 1 in 4 men (28.5%) in the United States have experienced rape, physical violence, and/or stalking by an intimate partner in their lifetime. Clinicians play an integral role on the screening, identification, and management of these sensitive issues.


Assuntos
Violência por Parceiro Íntimo , Estupro , Delitos Sexuais , Perseguição , Masculino , Humanos , Feminino , Estados Unidos/epidemiologia , Estupro/diagnóstico , Parceiros Sexuais
18.
Cell Rep ; 42(4): 112405, 2023 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-37071535

RESUMO

Upon activation, vinculin reinforces cytoskeletal anchorage during cell adhesion. Activating ligands classically disrupt intramolecular interactions between the vinculin head and tail domains that bind to actin filaments. Here, we show that Shigella IpaA triggers major allosteric changes in the head domain, leading to vinculin homo-oligomerization. Through the cooperative binding of its three vinculin-binding sites (VBSs), IpaA induces a striking reorientation of the D1 and D2 head subdomains associated with vinculin oligomerization. IpaA thus acts as a catalyst producing vinculin clusters that bundle actin at a distance from the activation site and trigger the formation of highly stable adhesions resisting the action of actin relaxing drugs. Unlike canonical activation, vinculin homo-oligomers induced by IpaA appear to keep a persistent imprint of the activated state in addition to their bundling activity, accounting for stable cell adhesion independent of force transduction and relevant to bacterial invasion.


Assuntos
Proteínas de Bactérias , Shigella , Proteínas de Bactérias/metabolismo , Antígenos de Bactérias/metabolismo , Actinas/metabolismo , Vinculina/metabolismo , Shigella/metabolismo , Ligação Proteica
19.
Transpl Infect Dis ; 25(2): e14041, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36864824

RESUMO

BACKGROUND: There is increased interest in bacteriophage (phage) therapy to treat infections caused by antibiotic-resistant bacteria. A lung transplant recipient with cystic fibrosis and Burkholderia multivorans infection was treated with inhaled phage therapy for 7 days before she died. METHODS: Phages were given via nebulization through the mechanical ventilation circuit. Remnant respiratory specimens and serum were collected. We quantified phage and bacterial deoxyribonucleic acid (DNA) using quantitative polymerase chain reaction, and tested phage neutralization in the presence of patient serum. We performed whole genome sequencing and antibiotic and phage susceptibility testing on 15 B. multivorans isolates. Finally, we extracted lipopolysaccharide (LPS) from two isolates and visualized their LPS using gel electrophoresis. RESULTS: Phage therapy was temporally followed by a temporary improvement in leukocytosis and hemodynamics, followed by worsening leukocytosis on day 5, deterioration on day 7, and death on day 8. We detected phage DNA in respiratory samples after 6 days of nebulized phage therapy. Bacterial DNA in respiratory samples decreased over time, and no serum neutralization was detected. Isolates collected between 2001 and 2020 were closely related but differed in their antibiotic and phage susceptibility profiles. Early isolates were not susceptible to the phage used for therapy, while later isolates, including two isolates collected during phage therapy, were susceptible. Susceptibility to the phage used for therapy was correlated with differences in O-antigen profiles of an early versus a late isolate. CONCLUSIONS: This case of clinical failure of nebulized phage therapy highlights the limitations, unknowns, and challenges of phage therapy for resistant infections.


Assuntos
Infecções por Burkholderia , Complexo Burkholderia cepacia , Fibrose Cística , Terapia por Fagos , Feminino , Humanos , Antibacterianos/uso terapêutico , Infecções por Burkholderia/tratamento farmacológico , Fibrose Cística/microbiologia , DNA/uso terapêutico , Leucocitose/tratamento farmacológico , Lipopolissacarídeos/uso terapêutico , Pulmão/microbiologia , Transplantados , Evolução Fatal , Adulto
20.
Diagnostics (Basel) ; 13(5)2023 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-36900138

RESUMO

Ascitic fluid infection is a serious complication of liver cirrhosis. The distinction between the more common spontaneous bacterial peritonitis (SBP) and the less common secondary peritonitis in patients with liver cirrhosis is crucial due to the varying treatment approaches. This retrospective multicentre study was conducted in three German hospitals and analysed 532 SBP episodes and 37 secondary peritonitis episodes. Overall, >30 clinical, microbiological, and laboratory parameters were evaluated to identify key differentiation criteria. Microbiological characteristics in ascites followed by severity of illness and clinicopathological parameters in ascites were the most important predictors identified by a random forest model to distinguish between SBP and secondary peritonitis. To establish a point-score model, a least absolute shrinkage and selection operator (LASSO) regression model selected the ten most promising discriminatory features. By aiming at a sensitivity of 95% either to rule out or rule in SBP episodes, two cut-off scores were defined, dividing patients with infected ascites into a low-risk (score ≥ 45) and high-risk group (score < 25) for secondary peritonitis. Overall, the discrimination of secondary peritonitis from SBP remains challenging. Our univariable analyses, random forest model, and LASSO point score may help clinicians with the crucial differentiation between SBP and secondary peritonitis.

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