Periprosthetic joint infection (PJI) occurring after artificial joint replacement is a major clinical issue requiring multiple surgeries and antibiotic interventions.
is the bacterium most commonly ...responsible for PJI. Recent
research has shown that staphylococcal strains rapidly form aggregates in the presence of synovial fluid (SF). We hypothesize that these aggregates provide early protection to bacteria entering the wound site, allowing them time to attach to the implant surface, leading to biofilm formation. Thus, understanding the attachment kinetics of these aggregates is critical in understanding their adhesion to various biomaterial surfaces. In this study, the number, size, and surface area coverage of aggregates as well as of single cells of
were quantified under various conditions on different orthopedic materials relevant to orthopedic surgery: stainless steel (316L), titanium (Ti), hydroxyapatite (HA), and polyethylene (PE). It was observed that, regardless of the material type, SF-induced aggregation resulted in reduced aggregate surface attachment and greater aggregate size than the single-cell populations under various shear stresses. Additionally, the surface area coverage of bacterial aggregates on PE was relatively high compared to that on other materials, which could potentially be due to the rougher surface of PE. Furthermore, increasing shear stress to 78 mPa decreased aggregate attachment to Ti and HA while increasing the aggregates' average size. Therefore, this study demonstrates that SF induced inhibition of aggregate attachment to all materials, suggesting that biofilm formation is initiated by lodging of aggregates on the surface features of implants and host tissues.
Periprosthetic joint infection occurring after artificial joint replacement is a major clinical issue that require repeated surgeries and antibiotic interventions. Unfortunately, 26% of patients die within 5 years of developing these infections.
is the bacterium most commonly responsible for this problem and can form biofilms to provide protection from antibiotics as well as the immune system. Although biofilms are evident on the infected implants, it is unclear how these are attached to the surface in the first place. Recent
investigations have shown that staphylococcal strains rapidly form aggregates in the presence of synovial fluid and provide protection to bacteria, thus allowing them time to attach to the implant surface, leading to biofilm formation. In this study, we investigated the attachment kinetics of
aggregates on different orthopedic materials. The information presented in this article will be useful in surgical management and implant design.
High Altitude Head and Neck Paragangliomas: A First Sub‐Himalayan Experience Kumar, Sudesh; Gupta, Niraj; Thakur, Priyanka ...
OTO open : the official open access journal of the American Academy of Otolaryngology--Head and Neck Surgery Foundation,
January–March 2024, Letnik:
8, Številka:
1
Journal Article
Recenzirano
Odprti dostop
Objectives
High‐altitude natives have a high incidence of parangangliomas (PGL) of the head and neck, especially the carotid body tumor. The aim of this study is to describe the clinical ...presentation, pattern, altitude of residence, distribution, management, and follow‐up of head and neck paragangliomas (HNPGL) in our sub‐Himalayan population.
Study Design
Retrospective cohort study.
Setting
Academic tertiary care hospital.
Methods
Hospital records of 20 patients of HNPGL diagnosed from December 2017 to December 2021 were retrieved for analysis.
Results
Twenty patients with 23 HNPGL, with a mean age of 41.74 years were managed in our institute. The female‐to‐male ratio was 2.3: 1 and the mean follow‐up was 29.95 months. Nine had carotid body (CBPGL), 7 had tympanic (TPGL), 2 had jugular (JPGL), and 2 had vagal paragangliomas (VPGL). Multiple PGL were seen in 4 patients (20%). Majority of cases (all CBPGL and 57.14% of TPGL) were residents of the high altitude, and the rest were from the low altitude. Fifteen patients (8 CBPGL, 7 TPGL) were operated. There were no major complications except in a patient with large carotid body tumor required anastomosis of carotid artery. Five patients received stereotactic radiotherapy, and 1 malignant PGL received chemoradiotherapy.
Conclusion
In this study, JPGL and VPGL are common at low altitudes, whereas carotid body and tympanic PGL were the most common tumor at high altitudes. Being a retrospective and study small sample size, a definite conclusion is not established, however, a genetic analysis and inclusion of a wider population in a future prospective study may establish the hypothesis.
Periprosthetic joint infection (PJI) occurring after artificial joint replacement is a major clinical issue requiring multiple surgeries and antibiotic interventions. Staphylococcus aureus is the ...common bacteria responsible for PJI. Recent in vitro research has shown that staphylococcal strains rapidly form free-floating aggregates in the presence of synovial fluid (SF) with biofilm-like resistance to antimicrobial agents. However, the development of biofilms formed from these aggregates under shear have not been widely investigated. Thus, in this study, we examined the progression of attached biofilms from free-floating aggregates. Biofilms were grown for 24 h in flow cells on titanium discs after inoculation with either pre-aggregated or single planktonic cells. Image analysis showed no significant difference between the biofilm formed from aggregates vs. the planktonic cells in terms of biomass, surface area, and thickness. Regarding antibiotic susceptibility, there were 1 and 2 log reductions in biofilms formed from single cells and aggregates, respectively, when treated with vancomycin for 24 h. Thus, this study demonstrates the formation of biofilm from free-floating aggregates and follows a similar developmental time period and shows similar antibiotic tolerance to more traditionally inoculated in vitro flow cell biofilms.
Of around half a million women dying of breast cancer each year, more than 90% die due to metastasis. Models necessary to understand the metastatic process, particularly breast cancer cell ...extravasation and colonization, are currently limited and urgently needed to develop therapeutic interventions necessary to prevent breast cancer metastasis. Microfluidic approaches aim to reconstitute functional units of organs that cannot be modeled easily in traditional cell culture or animal studies by reproducing vascular networks and parenchyma on a chip in a three-dimensional, physiologically relevant
system. In recent years, microfluidics models utilizing innovative biomaterials and micro-engineering technologies have shown great potential in our effort of mechanistic understanding of the breast cancer metastasis cascade by providing 3D constructs that can mimic
cellular microenvironment and the ability to visualize and monitor cellular interactions in real-time. In this review, we will provide readers with a detailed discussion on the application of the most up-to-date, state-of-the-art microfluidics-based breast cancer models, with a special focus on their application in the engineering approaches to recapitulate the metastasis process, including invasion, intravasation, extravasation, breast cancer metastasis organotropism, and metastasis niche formation.
Background: Multispecies biofilm orthopedic infections are more challenging to treat than mono-species infections. In this in-vitro study, we aimed to determine if a multispecies biofilm, consisting ...of Gram positive and negative species with different antibiotic susceptibilities could be treated more effectively using high purity antibiotic-loaded calcium sulfate beads (HP-ALCSB) containing vancomycin (VAN) and tobramycin (TOB) in combination than alone. Methods: Three sets of species pairs from bioluminescent strains of Pseudomonas aeruginosa (PA) and Staphylococcus aureus (SA) and clinical isolates, Enterococcus faecalis (EF) and Enterobacter cloacae were screened for compatibility. PA + EF developed intermixed biofilms with similar cell concentrations and so were grown on 316L stainless steel coupons for 72 h or as 24 h agar lawn biofilms and then treated with HP-ALCSBs with single or combination antibiotics and assessed by viable count or bioluminescence and light imaging to distinguish each species. Replica plating was used to assess viability. Results: The VAN + TOB bead significantly reduced the PA + EF biofilm CFU and reduced the concentration of surviving antibiotic tolerant variants by 50% compared to single antibiotics. Conclusions: The combination of Gram-negative and positive targeted antibiotics released from HP-ALCSBs may be more effective in treating multispecies biofilms than monotherapy alone.
Implant-associated infection is a major complication of orthopedic surgery. One of the most common organisms identified in periprosthetic joint infections is
a biofilm-forming pathogen. Orthopedic ...implants are composed of a variety of materials, such as titanium, polyethylene and stainless steel, which are at risk for colonization by bacterial biofilms. Little is known about how larger surface features of orthopedic hardware (such as ridges, holes, edges, etc.) influence biofilm formation and attachment. To study how biofilms might form on actual components, we submerged multiple orthopedic implants of various shapes, sizes, roughness and material type in brain heart infusion broth inoculated with
SAP231, a bioluminescent USA300 strain. Implants were incubated for 72 h with daily media exchanges. After incubation, implants were imaged using an in vitro imaging system (IVIS) and the metabolic signal produced by biofilms was quantified by image analysis. Scanning electron microscopy was then used to image different areas of the implants to complement the IVIS imaging. Rough surfaces had the greatest luminescence compared to edges or smooth surfaces on a single implant and across all implants when the images were merged. The luminescence of edges was also significantly greater than smooth surfaces. These data suggest implant roughness, as well as large-scale surface features, may be at greater risk of biofilm colonization.
Periprosthetic joint infection (PJI) after joint replacement is a major clinical issue requiring multiple surgeries and antibiotic interventions. Recent
research has shown that PJI staphylococcal ...strains rapidly form antibiotic-resistant free-floating aggregates in the presence of bovine synovial fluid (BSF). Staphylococcal aggregates are also present in human PJI joint fluid. However, the influence of surface roughness and fluid shear on the attachment and retention of such aggregates on surfaces is not known. Our aim was to assess how surface roughness and fluid shear stress influenced the attachment and retention of Staphylococcus aureus BSF-mediated aggregates on smooth- and rough-patterned titanium in flow cells compared to nonaggregated cells. The attachment of S. aureus aggregates was significantly greater than that of single cells but was independent of surface roughness; however, on the patterned surfaces, aggregates preferentially accumulated in the grooves. Fibrous components in the BSF were also colocalized with the grooves. After a 24-h attachment-and-incubation period, different shear stresses were applied. There was significant detachment from flat surfaces at a flow rate of 1 mL/min (τ
= 0.0012 Pa) but minimal detachment from the patterned surfaces, even at flow rates as high as 13.9 mL/min (τ
= 0.0169 Pa). The retention of bacterial aggregates and biofilms on rough surfaces exposed to shear might be an important consideration for the location of colonization on orthopedic implants, which can have wide ranges of roughness and surface features and can influence the efficacy of shear-based debridement methods such as pulse lavage.
Periprosthetic joint infections occurring after joint replacement are a major clinical problem requiring repeated surgeries and antibiotic interventions. Staphylococcus aureus is the most prominent bacterium causing most implant-related infections. S. aureus can form a biofilm, which is defined as a group of attached bacteria with the formation of an envelope that is resistant to antibiotics. The attachment and retention of these bacteria on implant surfaces are not clearly understood. Recent
research investigations have shown that staphylococcal strains rapidly form aggregates in the presence of bovine synovial fluid (BSF) in the joints, which allows bacteria time to attach to the implant surface, leading to biofilm formation. Thus, in this study, we examined the attachment of aggregates on titanium surfaces with varying roughnesses and found robust bacterial attachment and retention along the ridges and grooves, which colocalized with the deposition of fibrous components present in the BSF.
Various challenges arise when using phytoconstituents, such as the high molecular size, the destruction of drugs due to the lack of lipid solubility in the gastric system. Phospholipid complexation ...techniques are highly effective in notice these challenges as these techniques enhance the capability to move through permeable membranes and also prevent degradation of natural components by improving solubility. Phospholipid-complex technology, phospholipids complexes not only has the natural ability to release phytoconstituents into circulation, but with this technology they can easily be made into suitable dosage form such as solid unit dosage form. Drug -phospholipid complexes are an admirable choice for internal use because of the many characteristics that help improve it, such as biodegradable, non-toxic, with advantages such as employing them as solubilizers, emulsifiers, and as a matrix forming excipients for poor soluble, permeable drugs. This manuscript mainly focused on the information on different types of techniques used in the preparation of phospholipid complexes. The techniques employed in the formation of phospholipid complexes include selection of different types of phytoconstituents employed in complexes preparation and analytical method employed in its characterization technique also focused. The current review also focuses on basic information as to the best method for increasing the absorption of poorly absorbed plant components and increasing oral bioavailability. The advancement of phospholipid complex by an advanced technique was develop and utilized to based on drug delivery system which not only promotes natural components but also shows the importance of natural components in severe diseases like cancer and mental illnesses. Phospholipid complex drug delivery system is also effective in serious diseases like cancer, mental diseases and gastric problem. This manuscript also provide deep inside of recent patents associated with phospholipid complex in past decade.
PDF
