Mechanisms of Immune Evasion and Bone Tissue Colonization That Make Staphylococcus aureus the Primary Pathogen in Osteomyelitis

AbstractPurpose of ReviewStaphylococcus aureus is the primary pathogen responsible for osteomyelitis, which remains a major healthcare burden. To understand its dominance, here we review the unique pathogenic mechanisms utilized byS. aureus that enable it to cause incurable osteomyelitis.Recent FindingsUsing an arsenal of toxins and virulence proteins,S. aureus kills and usurps immune cells during infection, to produce non-neutralizing pathogenic antibodies that thwart adaptive immunity.S. aureus also has specific mechanisms for distinct biofilm formation on implants, necrotic bone tissue, bone marrow, and within the osteocyte lacuno-canicular networks (OLCN) of live bone. In vitro studies have also demonstrated potential for intracellular colonization of osteocytes, osteoblasts, and osteoclasts.SummaryS. aureus has evolved a multitude of virulence mechanisms to achieve life-long infection of the bone, most notably colonization of OLCN. TargetingS. aureus proteins involved in these pathways could provide new targets for antibiotics and immunotherapies.
Source: Current Osteoporosis Reports - Category: Orthopaedics Source Type: research

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This study assessed the difference in health-related quality of life (HRQOL) between participants with a mild to moderate adult sagittal deformity (ASD) (sagittal vertical axis [SVA] ≤9.5 cm) and those with a marked deformity (SVA>9.5 cm). We also evaluated predisposing factors for a marked deformity. Summary of Background Data. Sagittal imbalance is closely associated with HRQOL for the patient. However, how the effect changes depending on the degree of imbalance has not been fully evaluated. The understanding of the predisposing factor associated with marked deformity also lacks. Methods. A total of 124 e...
Source: Spine - Category: Orthopaedics Tags: HEALTH SERVICES RESEARCH Source Type: research
Conclusion: It was found that the majority of POEs containing a bioreducible center showed higher inhibitory activities on Mtb growth when compared to the similar compounds without a bio-reducible functional group. PMID: 31799156 [PubMed]
Source: BioImpacts - Category: Research Tags: Bioimpacts Source Type: research
Publication date: Available online 5 December 2019Source: Journal of Clinical and Experimental HepatologyAuthor(s): Waseem Amjad, Sandy Kotiah, Ankur Gupta, Michael Morris, Li Liu, Paul J. ThuluvathAbstractThe use of immunotherapy in transplant recipients is considered a contraindication because of very high risks for graft loss. The graft loss is to be expected since cytotoxic T-lymphocyte associated protein-4 (CTLA-4) and PD-1 pathways are implicated in graft tolerance. In this case report, we describe a woman with recurrent, disseminated hepatocellular carcinoma who was successfully treated with nivolumab, an immune checkpoint inhibitor.
Source: Journal of Clinical and Experimental Hepatology - Category: Gastroenterology Source Type: research
Authors: George E, Rajalakshmi A Abstract Melioidosis is an infectious disease caused by gram negative bacterium Burkholderia pseudomallei. It is a soil and water pathogen and transmitted to humans through inoculation or inhalation. This disease is considered endemic in India and largely remains under reported. The most common presentation is pneumonia and bacteraemia, which can present acutely and as septic shock. Chronic presentation include-abscess, septic arthritis, osteomyelitis. The major risk factors are diabetes, liver disease, renal disease, chronic lung disease. In this article 18 cases have been reviewed...
Source: Journal of the Association of Physicians of India - Category: General Medicine Tags: J Assoc Physicians India Source Type: research
ConclusionsIt was observed that extracts of S. hexaphylla inhibited both 5α -reductase type 2 and ARs. The results indicate that the use of S. hexaphylla extract in BPH is probably beneficial through 5α-reductase inhibition and α-adrenergic receptor blockade. In addition, apoptosis and autophagy were induced, and PCNA was downregulated after S. hexaphylla treatment. Therefore, it can be concluded that S. hexaphylla has a therapeutic effect on BPH.Graphical abstract
Source: Journal of Ethnopharmacology - Category: Drugs & Pharmacology Source Type: research
Authors: Skinner K PMID: 31795836 [PubMed - in process]
Source: International Journal of Hyperthermia - Category: Internal Medicine Tags: Int J Hyperthermia Source Type: research
The objective of this study was to investigate the impact of local-focused ultrasound (FUS) heating (∼42-45 °C) and in-situ anti-CD-40 agonistic antibody in enhancing T-cell function for melanoma immunotherapy. We compared the following groups of mice with bilateral flank B16 F10 melanoma: (1) Control, (2) FUS, (3) CD-40, and (4) CD-40 + FUS (FUS40). FUS heating was applied for ∼15 min in right flank tumor, and intratumoral injections of CD-40 were performed sequentially within 4 h. A total of 3 FUS and 4 anti-CD-40 treatments were administered unilaterally 3 days apart...
Source: International Journal of Hyperthermia - Category: Internal Medicine Tags: Int J Hyperthermia Source Type: research
Authors: Fiering SN, Evans S PMID: 31795831 [PubMed - in process]
Source: International Journal of Hyperthermia - Category: Internal Medicine Tags: Int J Hyperthermia Source Type: research
The objective response rate (ORR) was 30% (10/33), including three complete responses (CR) (9.1%) and seven partial responses (PR) (21.2%) and a disease control rate (DCR = CR + PR + SD) of 66.7% (22 of 33). The most common adverse reactions, blistering, subcutaneous fat induration, local heat-related pain, vomiting and sinus tachycardia, were observed in association with HT. IL-2, IL-4, TNF-α, and IFN-γ levels in peripheral blood were significantly increased among the clinical responders (p 
Source: International Journal of Hyperthermia - Category: Internal Medicine Tags: Int J Hyperthermia Source Type: research
Conclusions: These studies suggest that in addition to its role as a palliative therapeutic modality, RFA may have clinical potential as an immune-adjuvant therapy by augmenting the efficacy of adoptive T cell therapy. PMID: 31795828 [PubMed - in process]
Source: International Journal of Hyperthermia - Category: Internal Medicine Tags: Int J Hyperthermia Source Type: research
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