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1.
EMBO Rep ; 24(1): e54729, 2023 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-36341527

RESUMO

Chronic inflammation represents a major threat to human health since long-term systemic inflammation is known to affect distinct tissues and organs. Recently, solid evidence demonstrated that chronic inflammation affects hematopoiesis; however, how chronic inflammation affects hematopoietic stem cells (HSCs) on the mechanistic level is poorly understood. Here, we employ a mouse model of chronic multifocal osteomyelitis (CMO) to assess the effects of a spontaneously developed inflammatory condition on HSCs. We demonstrate that hematopoietic and nonhematopoietic compartments in CMO BM contribute to HSC expansion and impair their function. Remarkably, our results suggest that the typical features of murine multifocal osteomyelitis and the HSC phenotype are mechanistically decoupled. We show that the CMO environment imprints a myeloid gene signature and imposes a pro-inflammatory profile on HSCs. We identify IL-6 and the Jak/Stat3 signaling pathway as critical mediators. However, while IL-6 and Stat3 blockage reduce HSC numbers in CMO mice, only inhibition of Stat3 activity significantly rescues their fitness. Our data emphasize the detrimental effects of chronic inflammation on stem cell function, opening new venues for treatment.


Assuntos
Inflamação , Interleucina-6 , Humanos , Animais , Camundongos , Interleucina-6/genética , Interleucina-6/metabolismo , Inflamação/metabolismo , Transdução de Sinais , Hematopoese , Células-Tronco Hematopoéticas/metabolismo , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo
2.
Cell Mol Life Sci ; 81(1): 300, 2024 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-39001897

RESUMO

BACKGROUND: Age-associated impairments in innate immunity are believed to be a causative factor responsible for severe pathogenesis of Staphylococcus aureus (S. aureus) infection in the bone tissue. However, the basis for age-associated decline in innate immune response upon S. aureus infection remains poorly understood. RESULTS: Our transcriptional data (GEO: GSE166522) from a mouse model of S. aureus osteomyelitis show up-regulated CXCL9 and CXCL10 (CXCL9/10), which is further confirmed in vitro and in vivo by the present study. Notably, monocytes are a main source for CXCL9/10 production in bone marrow upon S. aureus challenge, but this response declines in middle-aged mice. Interestingly, conditional medium of bone marrow monocytes from middle-aged mice has a strikingly decreased effect on bactericidal functions of neutrophils and macrophages compares with that from young mice. We further show that activation of CXCL9/10-CXCR3 axis between monocytes and macrophages/neutrophils promotes the bactericidal function of the cells, whereas blocking the axis impairs such function. Importantly, treatment with either exogenous CXCL9 or CXCL10 in a middle-aged mice model enhances, while pharmacological inhibition of CXCR3 in young mice model impairs, bacterial clearance and bone marrow structure. CONCLUSIONS: These findings demonstrate that bone marrow monocytes act as a critical promotor of innate immune response via the CXLCL9/10-CXCR3 axis upon S. aureus infection, and that the increased susceptibility to S. aureus infection in skeleton in an aged host may be largely attributable to the declined induction of CXCR9/10 in monocytes.


Assuntos
Quimiocina CXCL10 , Quimiocina CXCL9 , Modelos Animais de Doenças , Imunidade Inata , Monócitos , Osteomielite , Infecções Estafilocócicas , Staphylococcus aureus , Animais , Osteomielite/microbiologia , Osteomielite/imunologia , Osteomielite/metabolismo , Osteomielite/patologia , Monócitos/imunologia , Monócitos/metabolismo , Quimiocina CXCL9/metabolismo , Quimiocina CXCL9/genética , Staphylococcus aureus/imunologia , Camundongos , Quimiocina CXCL10/metabolismo , Infecções Estafilocócicas/imunologia , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/patologia , Infecções Estafilocócicas/metabolismo , Camundongos Endogâmicos C57BL , Receptores CXCR3/metabolismo , Receptores CXCR3/genética , Envelhecimento/imunologia , Neutrófilos/imunologia , Neutrófilos/metabolismo , Macrófagos/imunologia , Macrófagos/metabolismo
3.
J Infect Dis ; 230(3): e568-e578, 2024 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-38409272

RESUMO

BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) sequence type (ST) 45 is a globally disseminated MRSA lineage. Herein, we investigated whether MRSA ST45 isolates from cellulitis and from osteomyelitis display distinctive phenotypic and genomic characteristics. METHODS: A total of 15 MRSA ST45 isolates from cellulitis (CL-MRSA; n = 6) or osteomyelitis (OM-MRSA; n = 9) were collected in a Taiwan hospital. These MRSA ST45 isolates were characterized for their antimicrobial susceptibility, biofilm-forming ability, cellular infectivity in vitro, and pathogenicity in vivo. Four CL-MRSA and 6 OM-MRSA ST45 isolates were selected for whole-genome sequencing (WGS). RESULTS: Antibiotic resistance tests showed that all OM-MRSA ST45 strains, but not CL-MRSA ST45 strains, were resistant to ciprofloxacin, levofloxacin, gentamicin, and doxycycline. Compared to the CL-MRSA ST45 isolates, the OM-MRSA ST45 isolates had stronger biofilm-forming ability and cellular infectivity and caused more severe disease in mice. WGS analysis revealed that these OM-MRSA ST45 isolates carry multiple common mutations or polymorphisms in genes associated with antibiotic resistance and virulence. Moreover, the transposable elements IS256 and IS257R2 were found only in the OM-MRSA ST45 isolates. CONCLUSIONS: The emergence and spread of the highly pathogenic and multidrug-resistant ST45 MRSAs identified from osteomyelitis may pose a serious threat on public health.


Assuntos
Antibacterianos , Biofilmes , Celulite (Flegmão) , Staphylococcus aureus Resistente à Meticilina , Testes de Sensibilidade Microbiana , Osteomielite , Infecções Estafilocócicas , Osteomielite/microbiologia , Taiwan , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Humanos , Infecções Estafilocócicas/microbiologia , Animais , Antibacterianos/farmacologia , Biofilmes/crescimento & desenvolvimento , Celulite (Flegmão)/microbiologia , Camundongos , Sequenciamento Completo do Genoma , Fenótipo , Feminino , Virulência/genética , Genoma Bacteriano , Masculino , Genômica
4.
J Infect Dis ; 230(3): 614-623, 2024 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-38537273

RESUMO

BACKGROUND: Bone infections with Staphylococcus aureus are notoriously difficult to treat and have high recurrence rates. Local antibiotic delivery systems hold the potential to achieve high in situ antibiotic concentrations, which are otherwise challenging to achieve via systemic administration. Existing solutions have been shown to confer suboptimal drug release and distribution. Here we present and evaluate an injectable in situ-forming depot system termed CarboCell. The CarboCell technology provides sustained and tuneable release of local high-dose antibiotics. METHODS: CarboCell formulations of levofloxacin or clindamycin with or without antimicrobial adjuvants cis-2-decenoic acid or cis-11-methyl-2-dodecenoic acid were tested in experimental rodent and porcine implant-associated osteomyelitis models. In the porcine models, debridement and treatment with CarboCell-formulated antibiotics was carried out without systemic antibiotic administration. The bacterial burden was determined by quantitative bacteriology. RESULTS: CarboCell formulations eliminated S. aureus in infected implant rat models. In the translational implant-associated pig model, surgical debridement and injection of clindamycin-releasing CarboCell formulations resulted in pathogen-free bone tissues and implants in 9 of 12 and full eradication in 5 of 12 pigs. CONCLUSIONS: Sustained release of antimicrobial agents mediated by the CarboCell technology demonstrated promising therapeutic efficacy in challenging translational models and may be beneficial in combination with the current standard of care.


Assuntos
Antibacterianos , Clindamicina , Osteomielite , Infecções Estafilocócicas , Staphylococcus aureus , Animais , Osteomielite/tratamento farmacológico , Osteomielite/microbiologia , Antibacterianos/administração & dosagem , Antibacterianos/uso terapêutico , Staphylococcus aureus/efeitos dos fármacos , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Suínos , Clindamicina/administração & dosagem , Clindamicina/uso terapêutico , Ratos , Modelos Animais de Doenças , Sistemas de Liberação de Medicamentos , Levofloxacino/administração & dosagem , Preparações de Ação Retardada , Feminino
5.
Clin Infect Dis ; 78(1): 40-47, 2024 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-37721158

RESUMO

BACKGROUND: Native vertebral osteomyelitis (NVO) caused by Staphylococcus aureus is associated with high risk of treatment failure and increased morbidity. The role of rifampin-based therapy for the treatment of this condition is controversial. The goal of this systematic review and meta-analysis is to explore the efficacy and safety of rifampin-based therapy for the treatment of S. aureus NVO. METHODS: We searched Cochrane, Embase, Medline, Scopus, and Web of Science databases for studies published up to May 2023, focusing on adults with NVO treated with or without rifampin-containing regimens. A random-effects model meta-analysis estimated relative risks and risk difference with 95% confidence intervals (CI). RESULTS: Thirteen studies (2 randomized controlled trials and 11 comparative cohort studies), comprising 244 patients with S. aureus NVO who received rifampin and 435 who did not, were analyzed. Meta-analysis showed that rifampin-based regimens were associated with lower risk of clinical failure (risk difference, -14%; 95% CI, -19% to -8%; P < .001; I2 = 0%; relative risk, 0.58; 95% CI, .37-.92, P = .02, I2 = 21%). Only 1 study reported on adverse events. All studies had a high or uncertain risk of bias, and the certainty of evidence was rated as very low. CONCLUSIONS: Adjunctive rifampin therapy might be associated with lower risk of S. aureus NVO treatment failure; however, the low certainty of evidence precludes drawing definitive conclusions that would alter clinical practice. A randomized trial is necessary to corroborate these findings.


Assuntos
Osteomielite , Infecções Estafilocócicas , Adulto , Humanos , Rifampina/uso terapêutico , Staphylococcus aureus , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/complicações , Protocolos Clínicos , Osteomielite/tratamento farmacológico , Osteomielite/etiologia
6.
Clin Infect Dis ; 79(3): 581-582, 2024 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-39325645

RESUMO

Managing pelvic osteomyelitis (POM) in the setting of stage IV pressure injuries requires multidisciplinary evaluation as well as patient and caregiver engagement and is complicated by the lack of high-evidence data to guide best practices. In this review, we describe our approach to pressure injury and POM evaluation and management through multidisciplinary collaboration and highlight areas of future research that are necessary to enhance patient outcomes, reduce healthcare costs, and improve the quality of life of those affected by POM.


Assuntos
Osteomielite , Úlcera por Pressão , Humanos , Osteomielite/terapia , Úlcera por Pressão/terapia , Pelve/lesões , Qualidade de Vida , Gerenciamento Clínico , Equipe de Assistência ao Paciente
7.
Clin Infect Dis ; 79(3): e11-e26, 2024 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-39325647

RESUMO

Managing pelvic osteomyelitis (POM) in the setting of stage IV pressure injuries requires multidisciplinary evaluation as well as patient and caregiver engagement and is complicated by the lack of high-evidence data to guide best practices. In this review, we describe our approach to pressure injury and POM evaluation and management through multidisciplinary collaboration and highlight areas of future research that are necessary to enhance patient outcomes, reduce healthcare costs, and improve the quality of life of those affected by POM.


Assuntos
Osteomielite , Úlcera por Pressão , Humanos , Osteomielite/tratamento farmacológico , Úlcera por Pressão/terapia , Pelve/lesões , Gerenciamento Clínico , Qualidade de Vida , Equipe de Assistência ao Paciente
8.
Clin Infect Dis ; 78(Suppl 1): S67-S70, 2024 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-38294110

RESUMO

Tularemia is caused by the highly infectious bacterium Francisella tularensis, which is recognized as a Tier 1 bioterrorism agent. Tularemia has a range of recognized clinical manifestations, but fewer than 20 bone or joint infections from 6 countries have been reported in the literature to date. This series includes 13 cases of F. tularensis septic arthritis or osteomyelitis in the United States during 2004-2023 and describes exposures, clinical presentation, diagnosis, and outcomes for this rare but severe form of tularemia. Clinicians should consider F. tularensis in patients with compatible exposures or a history of joint replacement or immunosuppression.


Assuntos
Artrite Infecciosa , Francisella tularensis , Tularemia , Humanos , Estados Unidos/epidemiologia , Tularemia/diagnóstico , Tularemia/epidemiologia , Tularemia/microbiologia , Artrite Infecciosa/diagnóstico , Artrite Infecciosa/epidemiologia
9.
Antimicrob Agents Chemother ; 68(10): e0069124, 2024 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-39287404

RESUMO

The therapeutic challenges of orthopedic device-related infections and emerging antimicrobial resistance have attracted attention to drug delivery technologies. This study evaluates the preclinical efficacy of local single- and dual-antibiotic therapy against implant-associated osteomyelitis (IAO) using a drug-eluting depot technology, CarboCell, that provides sustained release of high-dose antibiotics and allows for strategic in situ placement in relation to infectious lesions. Clindamycin and gentamicin were formulated in CarboCell compositions. One-stage-revision of tibial Staphylococcus aureus IAO was conducted in 19 pigs. Pigs were treated locally with CarboCell containing either gentamicin alone for 1 week or a co-formulation of gentamicin and clindamycin for 1 or 3 weeks. Bone, soft tissue, and antibiotic depots were collected for microbiology, histology, and HPLC analyses. Supporting in vivo release studies of CarboCell formulations were performed on mice. Both single- and dual-antibiotic CarboCell formulations were developed and capable of eradicating the infectious bacteria in bone and preventing colonization of implants inserted at revision. Eradication in soft tissue was observed in all pigs after 3 weeks and in 6/9 pigs after 1 week of treatment. Neutrophil counts in bone tissue were below the infection cut-off in all pigs receiving the dual-antibiotic therapies, but above in all pigs receiving the single-antibiotic therapy. Histological signs of active bone reorganization and healing were observed at 3 weeks. In conclusion, all CarboCell formulations demonstrated strong therapeutic activity against IAO, eradicating S. aureus in bone tissue and preventing colonization of implants even without the addition of systemic antibiotic therapy.


Assuntos
Antibacterianos , Clindamicina , Gentamicinas , Osteomielite , Infecções Estafilocócicas , Staphylococcus aureus , Animais , Gentamicinas/uso terapêutico , Gentamicinas/farmacologia , Osteomielite/tratamento farmacológico , Osteomielite/microbiologia , Clindamicina/uso terapêutico , Clindamicina/farmacologia , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Staphylococcus aureus/efeitos dos fármacos , Suínos , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Modelos Animais de Doenças , Camundongos , Infecções Relacionadas à Prótese/tratamento farmacológico , Infecções Relacionadas à Prótese/microbiologia , Feminino , Preparações de Ação Retardada
10.
Antimicrob Agents Chemother ; 68(10): e0080824, 2024 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-39194210

RESUMO

Osteomyelitis caused by Staphylococcus aureus can involve the persistent infection of osteocytes. We sought to determine if current clinically utilized antibiotics were capable of clearing an intracellular osteocyte S. aureus infection. Rifampicin, vancomycin, levofloxacin, ofloxacin, amoxicillin, oxacillin, doxycycline, linezolid, gentamicin, and tigecycline were assessed for their minimum inhibitory concentration (MIC) and minimum bactericidal concentrations against 12 S. aureus strains, at pH 5.0 and 7.2 to mimic lysosomal and cytoplasmic environments, respectively. Those antibiotics whose bone estimated achievable concentration was commonly above their respective MIC for the strains tested were further assayed in a human osteocyte infection model under acute and chronic conditions. Osteocyte-like cells were treated at 1×, 4×, and 10× the MIC for 1 and 7 days following infection (acute model), or at 15 and 21 days of infection (chronic model). The intracellular effectivity of each antibiotic was measured in terms of CFU reduction, small colony variant formation, and bacterial mRNA expression change. Only rifampicin, levofloxacin, and linezolid reduced intracellular CFU numbers significantly in the acute model. Consistent with the transition to a non-culturable state, few if any CFU could be recovered from the chronic model. However, no treatment in either model reduced the quantity of bacterial mRNA or prevented non-culturable bacteria from returning to a culturable state. These findings indicate that S. aureus adapts phenotypically during intracellular infection of osteocytes, adopting a reversible quiescent state that is protected against antibiotics, even at 10× their MIC. Thus, new therapeutic approaches are necessary to cure S. aureus intracellular infections in osteomyelitis.


Assuntos
Antibacterianos , Gentamicinas , Levofloxacino , Linezolida , Testes de Sensibilidade Microbiana , Osteócitos , Osteomielite , Rifampina , Infecções Estafilocócicas , Staphylococcus aureus , Vancomicina , Antibacterianos/farmacologia , Osteomielite/tratamento farmacológico , Osteomielite/microbiologia , Staphylococcus aureus/efeitos dos fármacos , Humanos , Osteócitos/efeitos dos fármacos , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Levofloxacino/farmacologia , Rifampina/farmacologia , Rifampina/uso terapêutico , Vancomicina/farmacologia , Linezolida/farmacologia , Gentamicinas/farmacologia , Tigeciclina/farmacologia , Ofloxacino/farmacologia , Doxiciclina/farmacologia , Amoxicilina/farmacologia , Oxacilina/farmacologia
11.
Antimicrob Agents Chemother ; 68(8): e0084724, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39037274

RESUMO

Deep-seated Candida spp. infections may necessitate extended durations of antifungal therapy. Increasing resistance to first-line antifungals threatens the most common options for long-term treatment. In this issue, Ponta et al. (Antimicrob Agents Chemother 68:e00750-24, 2024, https://doi.org/10.1128/aac.00750-24) present cases in which they used rezafungin, a novel long-acting echinocandin antifungal, for extended durations. While excellent clinical evidence supports the short-term safety of rezafungin, these cases demonstrate that rezafungin may additionally have a role in long-term suppressive therapy for antifungal-resistant Candida spp. infections.


Assuntos
Antifúngicos , Candida , Farmacorresistência Fúngica Múltipla , Equinocandinas , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Humanos , Candida/efeitos dos fármacos , Equinocandinas/farmacologia , Equinocandinas/uso terapêutico , Candidíase/tratamento farmacológico , Candidíase/microbiologia , Testes de Sensibilidade Microbiana
12.
Antimicrob Agents Chemother ; 68(5): e0018224, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38597672

RESUMO

Cephalexin, a first-generation cephalosporin, is the first-line oral therapy for children with musculoskeletal infections due to methicillin-susceptible Staphylococcus aureus (MSSA). Cefadroxil, a similar first-generation cephalosporin, is an attractive alternative to cephalexin given its longer half-life. In this study, we describe the comparative pharmacokinetics (PK) and pharmacodynamics (PD) of cephalexin and cefadroxil in children with musculoskeletal infections. Children aged 6 months to 18 years with a musculoskeletal infection were enrolled in a prospective, open-label, crossover PK study and given single oral doses of cefadroxil (50-75 mg/kg up to 2,000 mg) and cephalexin (50 mg/kg up to 1,375 mg). Population PK models were developed and used for dosing simulations. Our primary PD target was the achievement of free antibiotic concentrations above the minimum inhibitory concentration (fT >MIC) for 40% of the day for MICs ≤ 4 mg/L. PK of cephalexin (n = 15) and cefadroxil (n = 14) were best described using a one-compartment, first-order absorption model, with a lag time component for cefadroxil. PK parameters were notable for cefadroxil's longer half-life (1.61 h) than cephalexin's (1.10 h). For pediatric weight bands, our primary PD target was achieved by cephalexin 25 mg/kg/dose, maximum 750 mg/dose, administered three times daily and cefadroxil 40 mg/kg/dose, maximum 1,500 mg/dose, administered twice daily. More aggressive dosing was required to achieve higher PD targets. Among children with musculoskeletal infections, oral cephalexin and cefadroxil achieved PD targets for efficacy against MSSA. Given less frequent dosing, twice-daily cefadroxil should be further considered as an alternative to cephalexin for oral step-down therapy for serious infections due to MSSA.


Assuntos
Antibacterianos , Cefadroxila , Cefalexina , Estudos Cross-Over , Testes de Sensibilidade Microbiana , Cefalexina/farmacocinética , Cefalexina/uso terapêutico , Humanos , Criança , Antibacterianos/farmacocinética , Antibacterianos/uso terapêutico , Antibacterianos/farmacologia , Cefadroxila/farmacocinética , Cefadroxila/uso terapêutico , Feminino , Masculino , Pré-Escolar , Adolescente , Lactente , Estudos Prospectivos , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/efeitos dos fármacos
13.
Small ; 20(38): e2400732, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38764258

RESUMO

Currently, methicillin-resistant Staphylococcus aureus (MRSA)-induced osteomyelitis is a clinically life-threatening disease, however, long-term antibiotic treatment can lead to bacterial resistance, posing a huge challenge to treatment and public health. In this study, glucose-derived carbon spheres loaded with zinc oxide (ZnO@HTCS) are successfully constructed. This composite demonstrates the robust ability to generate reactive oxygen species (ROS) under ultrasound (US) irradiation, eradicating 99.788% ± 0.087% of MRSA within 15 min and effectively treating MRSA-induced osteomyelitis infection. Piezoelectric force microscopy tests and finite element method simulations reveal that the ZnO@HTCS composite exhibits superior piezoelectric catalytic performance compared to pure ZnO, making it a unique piezoelectric sonosensitizer. Density functional theory calculations reveal that the formation of a Mott-Schottky heterojunction and an internal piezoelectric field within the interface accelerates the electron transfer and the separation of electron-hole pairs. Concurrently, surface vacancies of the composite enable the adsorption of a greater amount of oxygen, enhancing the piezoelectric catalytic effect and generating a substantial quantity of ROS. This work not only presents a promising approach for augmenting piezoelectric catalysis through construction of a Schottky heterojunction interface but also provides a novel, efficient therapeutic strategy for treating osteomyelitis.


Assuntos
Carbono , Glucose , Staphylococcus aureus Resistente à Meticilina , Osteomielite , Óxido de Zinco , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Osteomielite/tratamento farmacológico , Óxido de Zinco/química , Carbono/química , Catálise , Glucose/química , Ondas Ultrassônicas , Animais , Espécies Reativas de Oxigênio/metabolismo , Infecções Estafilocócicas/tratamento farmacológico
14.
Small ; 20(15): e2307406, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38009734

RESUMO

Osteomyelitis caused by deep tissue infections is difficult to cure through phototherapy due to the poor penetration depth of the light. Herein, Cu/C/Fe3O4-COOH nanorod composites (Cu/C/Fe3O4-COOH) with nanoscale tip convex structures are successfully fabricated as a microwave-responsive smart bacteria-capture-killing vector. Cu/C/Fe3O4-COOH exhibited excellent magnetic targeting and bacteria-capturing ability due to its magnetism and high selectivity affinity to the amino groups on the surface of Staphylococcus aureus (S. aureus). Under microwave irradiation, Cu/C/Fe3O4-COOH efficiently treated S. aureus-infected osteomyelitis through the synergistic effects of microwave thermal therapy, microwave dynamic therapy, and copper ion therapy. It is calculated the electric field intensity in various regions of Cu/C/Fe3O4-COOH under microwave irradiation, demonstrating that it obtained the highest electric field intensity on the surface of copper nanoparticles of Cu/C/Fe3O4-COOH due to its high-curvature tips and metallic properties. This led to copper nanoparticles attracted more charged particles compared with other areas in Cu/C/Fe3O4-COOH. These charges are easier to escape from the high curvature surface of Cu/C/Fe3O4-COOH, and captured by adsorbed oxygen, resulting in the generation of reactive oxygen species. The Cu/C/Fe3O4-COOH designed in this study is expected to provide insight into the treatment of deep tissue infections under the irradiation of microwave.


Assuntos
Nanopartículas , Osteomielite , Infecções Estafilocócicas , Humanos , Staphylococcus aureus , Cobre/química , Micro-Ondas/uso terapêutico , Nanopartículas/química , Infecções Estafilocócicas/terapia , Osteomielite/terapia
15.
Small ; 20(28): e2312280, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38312094

RESUMO

Antibiotics are frequently used to clinically treat osteomyelitis caused by bacterial infections. However, extended antibiotic use may result in drug resistance, which can be life threatening. Here, a heterojunction comprising Fe2O3/Fe3S4 magnetic composite is constructed to achieve short-term and efficient treat osteomyelitis caused by methicillin-resistant Staphylococcus aureus (MRSA). The Fe2O3/Fe3S4 composite exhibits powerful microwave (MW) absorption properties, thereby effectively converting incident electromagnetic energy into thermal energy. Density functional theory calculations demonstrate that Fe2O3/Fe3S4 possesses significant charge accumulation and oxygen-fixing capacity at the heterogeneous interface, which provides more active sites and oxygen sources for trapping electromagnetic hotspots. The finite element analysis indicates that Fe2O3/Fe3S4 displays a larger electromagnetism field enhancement parameter than Fe2O3 owing to a significant increase in electromagnetic hotspots. These hotspots contribute to charge differential accumulation and depletion motions at the interface, thereby augmenting the release of free electrons that subsequently combine with the oxygen adsorbed by Fe2O3/Fe3S4 to generate reactive oxygen species (ROS) and heat. This research, which achieves extraordinary bacterial eradication through the synergistic effect of microwave thermal therapy (MWTT) and microwave dynamic therapy (MDT), presents a novel strategy for treating deep-tissue bacterial infections.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Micro-Ondas , Osteomielite , Oxigênio , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Osteomielite/terapia , Osteomielite/tratamento farmacológico , Oxigênio/química , Elétrons , Animais , Camundongos
16.
J Autoimmun ; 144: 103183, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38401466

RESUMO

Chronic nonbacterial osteomyelitis (CNO), an autoinflammatory bone disease primarily affecting children, can cause pain, hyperostosis and fractures, affecting quality-of-life and psychomotor development. This study investigated CNO-associated variants in P2RX7, encoding for the ATP-dependent trans-membrane K+ channel P2X7, and their effects on NLRP3 inflammasome assembly. Whole exome sequencing in two related transgenerational CNO patients, and target sequencing of P2RX7 in a large CNO cohort (N = 190) were conducted. Results were compared with publicly available datasets and regional controls (N = 1873). Findings were integrated with demographic and clinical data. Patient-derived monocytes and genetically modified THP-1 cells were used to investigate potassium flux, inflammasome assembly, pyroptosis, and cytokine release. Rare presumably damaging P2RX7 variants were identified in two related CNO patients. Targeted P2RX7 sequencing identified 62 CNO patients with rare variants (32.4%), 11 of which (5.8%) carried presumably damaging variants (MAF <1%, SIFT "deleterious", Polyphen "probably damaging", CADD >20). This compared to 83 of 1873 controls (4.4%), 36 with rare and presumably damaging variants (1.9%). Across the CNO cohort, rare variants unique to one (Median: 42 versus 3.7) or more (≤11 patients) participants were over-represented when compared to 190 randomly selected controls. Patients with rare damaging variants more frequently experienced gastrointestinal symptoms and lymphadenopathy while having less spinal, joint and skin involvement (psoriasis). Monocyte-derived macrophages from patients, and genetically modified THP-1-derived macrophages reconstituted with CNO-associated P2RX7 variants exhibited altered potassium flux, inflammasome assembly, IL-1ß and IL-18 release, and pyroptosis. Damaging P2RX7 variants occur in a small subset of CNO patients, and rare P2RX7 variants may represent a CNO risk factor. Observations argue for inflammasome inhibition and/or cytokine blockade and may allow future patient stratification and individualized care.


Assuntos
Inflamassomos , Osteomielite , Humanos , Citocinas , Inflamassomos/genética , Inflamassomos/metabolismo , Osteomielite/genética , Potássio , Piroptose , Receptores Purinérgicos P2X7/genética
17.
Artigo em Inglês | MEDLINE | ID: mdl-38775453

RESUMO

OBJECTIVES: Chronic recurrent multifocal osteomyelitis (CRMO) is an autoinflammatory disease characterized by sterile bone inflammation; however, its pathophysiology is poorly understood. Thus, this study aimed to characterize the serum proteomic profiles of patients with CRMO to better understand the molecular mechanisms underpinning CRMO pathogenesis. METHODS: Proteomic profiling of the sera collected from 11 patients with CRMO (five patients were in active phase, six were in inactive phase) was conducted using liquid chromatography-mass spectrometry. Sera from four children without inflammatory diseases were used as controls. Pathway analysis was performed to identify the upregulated and downregulated proteins in patients with active CRMO. RESULTS: Compared with the control group, 19 and 41 proteins were upregulated and downregulated, respectively, in patients with active CRMO. Pathway and process enrichment analyses revealed that axon guidance was the most enriched category of upregulated proteins in patients with active CRMO, followed by neutrophil degranulation and mitogen-activated protein kinase cascade regulation. In comparison to patients with inactive CRMO, 36 proteins, including 11 keratin proteins, were upregulated and highly enriched in the intermediate filament organization category. Rho GTPase pathway-related proteins were downregulated in ibuprofen-treated patients. CONCLUSION: Proteomic analysis identified upregulated proteins in the sera of patients with acute CRMO. These proteins can be used as biomarkers for disease diagnosis and activity. Furthermore, we anticipate that this study will contribute to a deeper understanding of the pathophysiology of CRMO, which, in turn, will contribute to the discovery of potential novel therapeutic targets.

18.
Artigo em Inglês | MEDLINE | ID: mdl-39167099

RESUMO

OBJECTIVES: Chronic Recurrent Multifocal Osteomyelitis (CRMO), also known as chronic nonbacterial osteomyelitis (CNO), is a rare autoinflammatory condition affecting the bones in children and teenagers. The actual incidence of CRMO remains uncertain. The objective of this study is to identify the incidence of CRMO in children and young people under the age of 16 years in the United Kingdom (UK) and Republic of Ireland (ROI). We also aim to delineate the demographics, clinical presentation, investigations, initial management and healthcare needs for children and adolescents with CRMO. METHODS: We conducted monthly surveys among all paediatric consultants and paediatric orthopaedic surgeons to identify patients newly diagnosed with CRMO between October 2020 and November 2022. A standardised questionnaire was sent to reporting clinicians to collect further information. RESULTS: Over the surveillance period, 288 patients were reported, among which, 165 confirmed and 20 probable cases were included in the analysis. The highest incidences were among 8-10 year-olds. A two-to-one female-to-male difference in incidence was observed, and male patients were more likely to present with multifocal disease. A negative correlation was observed between reporting clavicular and leg pain. Investigation-wise, 80.0% of patients were reported to have undergone whole-body MRI and 51.1% had bone biopsies. The most common initial treatments were NSAIDs (93.9%) and bisphosphonates (44.8%). CONCLUSION: This study estimates an average annual CRMO incidence of 0.65 cases per 100 000 children and adolescents in the UK and ROI. These findings establish a crucial baseline for ongoing research and improvement in the care of individuals with CRMO.

19.
Artigo em Inglês | MEDLINE | ID: mdl-39042221

RESUMO

OBJECTIVES: Primary chronic Non-Bacterial Osteomyelitis of the jaw is a rare auto-inflammatory disease of unknown aetiology that bears pathophysiological resemblance to both the synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome in adults and chronic recurrent multifocal osteomyelitis (CRMO) in children. Both SAPHO and CRMO respond to TNF-alpha blockade. Previously reported treatment regimens in CNOM including non-steroidal anti-inflammatory drugs, corticosteroids, antibiotics, anti-resorptive therapy, and surgery all bear disappointing results. TNF- α blockade is suggested as a treatment option by some experts but this is not backed by any clinical data.We sought to retrospectively and exhaustively report our experience of anti-TNF alpha therapy in refractory CNOM. METHODS: Fifteen patients with refractory CNOM and high disease burden were referred to our centre. TNF- α blockade was attempted in 10 cases, given its efficacy in neighbouring diseases, its good tolerance profile and failure of previous treatment strategiesWe herein retrospectively report detailed outcomes for all patients having received anti-TNF alpha therapy for this indication in our centre. RESULTS: TNF-α-targeting therapy resulted in a rapid and sustained remission in a majority of patients with CNOM, without serious adverse events. Treatment was tapered and stopped without relapse in some patients despite a refractory course of several years. Male sex seems to be associated with a poorer outcome. CONCLUSION: Our results suggest that blocking TNF-α is efficient and safe in CNOM.

20.
J Vasc Surg ; 79(3): 632-641.e3, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37939747

RESUMO

OBJECTIVE: There is no established consensus or guidelines for wound management after revascularization for patients with chronic limb-threatening ischemia (CLTI) without severe infection. This study is designed to evaluate the clinical effect of the wound management strategy on toe wounds after revascularization for CLTI. METHODS: This retrospective cohort study was performed at eight institutions affiliated with Keio University School of Medicine in Japan and included 261 patients who underwent revascularization for CLTI between April 2019 and July 2021. We identified 132 patients with toe wounds from the database who had restored in-line blood flow to the foot. Patients were divided into two groups by the timing of toe resection after revascularization, which dictated the wound management policy. Group A (62 patients) underwent early toe amputation for suspected osteomyelitis, whereas group B (70 patients) underwent watchful waiting. The primary outcome was wound healing after revascularization; the secondary outcome was major amputation. We compared outcomes between groups A and B after propensity score matching. RESULTS: Using propensity score matching, each patient in group A (33 patients) was matched with a patient in group B (33 patients). Wound healing in matched group A was significantly better than that in matched group B (respectively: 1-year wound healing rate: 90.0% vs 68.2%, P < .001; median wound healing time: 65 days vs 258 days, P < .01). Although five major amputations were necessary in matched group B, none were required in matched group A (P = .05). The high rate of major amputations in group B was attributed to the sudden exacerbation of infection. Limb salvage rate in matched group A exceeded matched group B (100.0% vs 90.5%: 1-year limb salvage rate, P = .02). CONCLUSIONS: Early toe amputation for highly suspected osteomyelitis in patients with CLTI with toe wounds may expedite wound healing compared with watchful waiting, potentially avoiding unnecessary major amputation. Considering the wound management strategy is crucial when evaluating wound healing outcomes in patients with CLTI with revascularization.


Assuntos
Procedimentos Endovasculares , Osteomielite , Doença Arterial Periférica , Humanos , Isquemia Crônica Crítica de Membro , Estudos Retrospectivos , Resultado do Tratamento , Fatores de Risco , Isquemia/diagnóstico por imagem , Isquemia/cirurgia , Salvamento de Membro/efeitos adversos , Doença Crônica , Procedimentos Endovasculares/efeitos adversos
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