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1.
Cureus ; 16(3): e56274, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38623105

ABSTRACT

This case report details a unique presentation of an infiltrative intramuscular lipoma in the anterior thigh of a 51-year-old female with an overlying fascial defect. The patient reported a progressively enlarging left thigh mass associated with pain exacerbated by knee movement and exercise. MRI revealed a homogeneous intramuscular lipoma without contrast enhancement with a fascial defect. An 8 cm longitudinal incision exposed a 7 x 4 cm fascial defect overlying the lipomatous mass within the rectus femoris muscle. Pathological analysis confirmed an intramuscular lipoma without malignancy. Follow-ups at two, six, and 12 weeks demonstrated pain resolution and no soft tissue bulge. This case underscores the importance of distinguishing intramuscular lipomas from other neoplasms, such as lipomatosis and liposarcomas. The association of a fascial defect with intramuscular lipomas is unprecedented and may be due to the increased pressure on the fascia by the lipoma. The report emphasizes the role of MRI in diagnosis and appropriate surgical management, and highlights the need for further exploration into the etiology of fascial defects associated with intramuscular lipomas.

2.
J Hosp Infect ; 145: 193-202, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38215945

ABSTRACT

BACKGROUND: Reports of nosocomial infections typically describe recognised microorganisms. Here, a novel bacterial species was isolated, based on rectal swab screening for carbapenemases post-admission, then phenotypically and genetically characterized. METHODS: Sensititre, Vitek and API kits, MALDI and Illumina MiSeq were employed before profiles and phylogeny were compared with other related species. FINDINGS: Determined to be a possible Enterobacterales, the isolate was found to have 99.7% 16s rRNA identity to Pseudocitrobacter corydidari; an Asian cockroach-associated species. Given the highly conserved/low variability of 16S rRNA genes in Enterobacterales, average nucleotide identity (ANI) analysis compared the new isolate's genome with those of 18 Enterobacteriaceae species, including confirmed species of Pseudocitrobacter and unnamed Pseudocitrobacter species in the SILVA database. Of these, Pseudocitrobactercorydidari had the highest ANI at 0.9562. The published genome of the only known isolate of P.corydidari does not include Antimicrobial Resistance Genes (ARGs), with exception of potential drug efflux transporters. In contrast, our clinical isolate bears recognised antimicrobial resistance genes, including Klebsiella pneumoniae carbapenemase. The associated genome suggests resistance to carbapenems, ß-lactams, sulfonamides, fluoroquinolones, macrolides, aminoglycosides and cephalosporins. Phenotypic antimicrobial resistance was confirmed. CONCLUSION: Evident variations in ARG profiles, human colonization and origin in a clinically relevant niche that is geographically, physically and chemically disparate lend credibility for divergent evolution or, less likely, parallel evolution with P. corydidari. Genome data for this new species have been submitted to GENBANK using the proposed nomenclature Pseudocitrobacter limerickensis. The patient was colonized, rather than infected, and did not require antimicrobial treatment.


Subject(s)
Anti-Bacterial Agents , Enterobacteriaceae , Humans , RNA, Ribosomal, 16S/genetics , Enterobacteriaceae/genetics , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Fluoroquinolones/therapeutic use , Klebsiella pneumoniae , beta-Lactamases/genetics , Hospitals, Teaching , Microbial Sensitivity Tests
3.
J Hosp Infect ; 141: 152-166, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37696473

ABSTRACT

BACKGROUND: Hospital-acquired infections (HAIs) and infectious agents exhibiting antimicrobial resistance (AMR) are challenges globally. Environmental patient-facing wastewater apparatus including handwashing sinks, showers and toilets are increasingly identified as sources of infectious agents and AMR genes. AIM: To provide large-scale metagenomics analysis of wastewater systems in a large teaching hospital in the Republic of Ireland experiencing multi-drug-resistant HAI outbreaks. METHODS: Wastewater pipe sections (N=20) were removed immediately prior to refurbishment of a medical ward where HAIs had been endemic. These comprised toilet U-bends, and sink and shower drains. Following DNA extraction, each pipe section underwent metagenomic analysis. FINDINGS: Diverse taxonomic and resistome profiles were observed, with members of phyla Proteobacteria and Actinobacteria dominating (38.23 ± 5.68% and 15.78 ± 3.53%, respectively). Genomes of five clinical isolates were analysed. These AMR bacterial isolates were from patients >48 h post-admission to the ward. Genomic analysis determined that the isolates bore a high number of antimicrobial resistance genes (ARGs). CONCLUSION: Comparison of resistome profiles of isolates and wastewater metagenomes revealed high degrees of similarity, with many identical ARGs shared, suggesting probable acquisition post-admission. The highest numbers of ARGs observed were those encoding resistance to clinically significant and commonly used antibiotic classes. Average nucleotide identity analysis confirmed the presence of highly similar or identical genomes in clinical isolates and wastewater pipes. These unique large-scale analyses reinforce the need for regular cleaning and decontamination of patient-facing hospital wastewater pipes and effective infection control policies to prevent transmission of nosocomial infection and emergence of AMR within potential wastewater reservoirs.


Subject(s)
Biological Products , Cross Infection , Microbiota , Humans , Wastewater , Microbiota/genetics , Hospitals, Teaching , Anti-Bacterial Agents , Cross Infection/epidemiology , Genes, Bacterial
4.
AJNR Am J Neuroradiol ; 42(4): 774-781, 2021 04.
Article in English | MEDLINE | ID: mdl-33602745

ABSTRACT

BACKGROUND AND PURPOSE: Head motion causes image degradation in brain MR imaging examinations, negatively impacting image quality, especially in pediatric populations. Here, we used a retrospective motion correction technique in children and assessed image quality improvement for 3D MR imaging acquisitions. MATERIALS AND METHODS: We prospectively acquired brain MR imaging at 3T using 3D sequences, T1-weighted MPRAGE, T2-weighted TSE, and FLAIR in 32 unsedated children, including 7 with epilepsy (age range, 2-18 years). We implemented a novel motion correction technique through a modification of k-space data acquisition: Distributed and Incoherent Sample Orders for Reconstruction Deblurring by using Encoding Redundancy (DISORDER). For each participant and technique, we obtained 3 reconstructions as acquired (Aq), after DISORDER motion correction (Di), and Di with additional outlier rejection (DiOut). We analyzed 288 images quantitatively, measuring 2 objective no-reference image quality metrics: gradient entropy (GE) and MPRAGE white matter (WM) homogeneity. As a qualitative metric, we presented blinded and randomized images to 2 expert neuroradiologists who scored them for clinical readability. RESULTS: Both image quality metrics improved after motion correction for all modalities, and improvement correlated with the amount of intrascan motion. Neuroradiologists also considered the motion corrected images as of higher quality (Wilcoxon z = -3.164 for MPRAGE; z = -2.066 for TSE; z = -2.645 for FLAIR; all P < .05). CONCLUSIONS: Retrospective image motion correction with DISORDER increased image quality both from an objective and qualitative perspective. In 75% of sessions, at least 1 sequence was improved by this approach, indicating the benefit of this technique in unsedated children for both clinical and research environments.


Subject(s)
Artifacts , Neuroimaging , Adolescent , Brain/diagnostic imaging , Child , Child, Preschool , Humans , Magnetic Resonance Imaging , Motion , Retrospective Studies
5.
Int J Pharm Compd ; 24(1): 30-36, 2020.
Article in English | MEDLINE | ID: mdl-32023214

ABSTRACT

United States Pharmacopeia Chapter <800>, concerned with the handling of hazardous drugs in healthcare settings, requires that any entity handling such drugs maintain a hazardous drug list. While this list must include any drug found on the latest NIOSH List of Antineoplastic and Other Hazardous Drugs in Health Settings, entities are expected to include other drugs and substances of concern. The intent of this article is to provide concrete information concerning articles of personal protective equipment, as well as guidance as to where and how they should be donned, used, and removed. This information will cover every aspect of handling hazardous drugs from receipt to disposal, most certainly including both sterile and nonsterile compounding.


Subject(s)
Antineoplastic Agents , Hazardous Substances/adverse effects , Occupational Exposure , Antineoplastic Agents/adverse effects , Antineoplastic Agents/chemistry , Chemical Safety/standards , Hazardous Substances/chemistry , Occupational Exposure/prevention & control , Occupational Exposure/standards , Personal Protective Equipment , Quality Control
6.
Int J Pharm Compd ; 23(3): 182-186, 2019.
Article in English | MEDLINE | ID: mdl-31085785

ABSTRACT

United States Pharmacopeia Chapter <800>, concerned with the handling of hazardous drugs in healthcare settings, requires that any entity handling such drugs maintain a hazardous drug list. While this list must include any drug found on the latest NIOSH List of Antineoplastic and Other Hazardous Drugs in Healthcare Settings, entities are expected to include other drugs and substances of concern. This article provides guidance on the creation and maintenance of such a list.


Subject(s)
Hazardous Substances , Occupational Exposure , Antineoplastic Agents/analysis , Antineoplastic Agents/standards , Hazardous Substances/analysis , Hazardous Substances/standards , Occupational Exposure/analysis , Occupational Exposure/prevention & control , Occupational Health/standards , United States
7.
J Health Econ Outcomes Res ; 6(2): 95-105, 2019.
Article in English | MEDLINE | ID: mdl-32685583

ABSTRACT

BACKGROUND: Bifurcation lesions represent 15-20% of all patients undergoing a percutaneous coronary intervention (PCI) for coronary artery disease. The provisional 1-stent stenting strategy is the preferred strategy to treat bifurcation lesions. Other strategies used to treat bifurcation lesions include 2-stent complex stenting strategies and the Tryton Side Branch Stent® (TSB)-a dedicated side-branch stent for bifurcation lesions, which gained FDA approval in March 2017. OBJECTIVES: To conduct a systematic literature review of the safety and effectiveness of three stenting strategies (provisional, complex, and Tryton Side Branch Stent®) for bifurcation lesions with a side-branch diameter ≥2.25 mm, undergoing PCI. METHODS: Literature searches in Medline, Cochrane Library, Web of Science and Embase were conducted to identify prospective clinical trials from January 2007-July 2017. RESULTS: 602 articles were identified. Nine articles (6275 patients) met all inclusion criteria. Seven studies (5282 patients) compared provisional to complex stenting strategies. Two studies (993 patients) compared provisional to the TSB. Outcomes of interest reported were target vessel failure in 2 studies, major adverse cardiac event (MACE) (cardiac death, all myocardial infarction, ischemic driven target legion revascularization TLR) in 5 studies. For target vessel failure, the provisional strategy ranged from 5.6% to 15.6 %; complex at 7.2% (one study); and TSB from 11.3% to 17.4%. For MACE, provisional strategy ranged from 8%-13.2%; complex from 11.9%-15.2%; and TSB from 8.2%-18.6%. CONCLUSIONS: To our knowledge, this is the first review comparing three bifurcation lesion stenting strategies. Significant heterogeneity in the study design of the nine studies reviewed prevented a meta-analysis. A clinical trial comparing the TSB to both the provisional and complex strategies would provide better inference on the safety and effectiveness when comparing strategies.

8.
Gynecol Oncol ; 148(2): 357-362, 2018 02.
Article in English | MEDLINE | ID: mdl-29276057

ABSTRACT

OBJECTIVE: HPV genotype distribution varies by race/ethnicity, but is unclear whether there are racial/ethnic variations in HPV 16/18 integration in the host genome. We describe HPV16/18 infection and integration status in a racially/ethnically diverse sample of women with a recent abnormal Pap test. METHODS: Patients (n=640) represent a subset of women participating in a clinical trial. Cervical swabs were tested for HPV16/18 DNA using type-specific polymerase chain reaction assays. Viral integration status was assessed using type-specific integration assays and categorized as fully integrated, fully non-integrated, or mixed. Unconditional logistic regression was used to generate unadjusted (OR) and adjusted odds ratios (aOR) to assess the association between self-reported race/ethnicity and risk of these outcomes. RESULTS: Hispanic and non-Hispanic black women had half the odds of prevalent HPV16 compared to non-Hispanic white women (aORs: 0.43 and 0.45, respectively). The prevalence odds of HPV18 was less than half among Hispanic women (aOR: 0.48), but not significantly different between black and white women (aOR: 0.72). Among women with prevalent HPV16, the odds of fully integrated viral DNA were significantly higher among black women (aORs: 2.78) and marginally higher among Hispanic women (aOR: 1.93). No racial/ethnic differences were observed for HPV18 DNA integration. CONCLUSIONS: While HPV16 and 18 infections were less prevalent among Hispanic and black women compared to whites, their HPV16 DNA was more likely to be present in a fully integrated state. This could potentially contribute to the higher rates of abnormal cytology and cervical dysplasia observed among Hispanic and black women.


Subject(s)
Human papillomavirus 16/genetics , Human papillomavirus 18/genetics , Papillomavirus Infections/ethnology , Uterine Cervical Neoplasms/virology , Adolescent , Adult , Black or African American/ethnology , Aged , Canada/epidemiology , DNA, Viral/genetics , Female , Genotype , Hispanic or Latino , Humans , Middle Aged , Papillomavirus Infections/genetics , Prevalence , United States/epidemiology , Unsafe Sex/ethnology , Uterine Cervical Neoplasms/genetics , Virus Integration , White People , Young Adult
9.
Int J Pharm Compd ; 20(6): 469-474, 2016.
Article in English | MEDLINE | ID: mdl-28339385

ABSTRACT

The Pharmacy Compounding Accreditation Board's goal is to assist pharmacies to obtain formal recognition of their status as a high-quality and fully compliant provider of pharmaceuticals and patient services. This article provides a brief outline of the application process, the survey preparation, points of information about the actual survey, and suggestions on how to remain in compliance with Pharmacy Compounding Accreditation Board's standards.


Subject(s)
Accreditation/standards , Clinical Competence/standards , Drug Compounding/standards , Pharmacists/standards , Specialty Boards/standards , Clinical Competence/legislation & jurisprudence , Humans , Pharmacists/legislation & jurisprudence , Quality Indicators, Health Care/standards , Specialty Boards/legislation & jurisprudence
10.
Appl Phys Lett ; 109(26): 263106, 2016 12 26.
Article in English | MEDLINE | ID: mdl-28104921

ABSTRACT

Gold nanoparticles (AuNPs) have been increasingly integrated in biological systems, making it imperative to understand their interactions with cell membranes, the first barriers to be crossed to enter cells. Herein, liposomes composed of 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) as a model membrane system were treated with citrate stabilized AuNPs from 5 to 30 nm at various concentrations. The fluorescence shifts of Laurdan probes reveal that AuNPs in general made liposomes more fluidic. The increased fluidity is expected to result in an increased surface area, and thus liposome shape changes from circular to less circular, which was further confirmed with fluorescence microscopy. The localized stress in lipids induced by electrostatically adsorbed AuNPs was hypothesized to cause the dominant long-range effect of fluidization of unbound lipid membranes. A secondary effect of the AuNP-induced lateral pressure is the membrane rupture or formation of pores, which was probed by AFM under fluid. We found in this study a nanoparticle-mediated approach of modulating the stiffness of lipid membranes: by adsorption of AuNPs, lipids at the binding sites are stiffened whereas lipids afar are fluidized. Understanding the factors that modulate lipid packing is important for the discovery of alternative therapeutic methods for diseases linked to membrane integrity such as high blood pressure and cancer metastasis.

11.
Int J Pharm Compd ; 19(2): 109-12, 2015.
Article in English | MEDLINE | ID: mdl-26685491

ABSTRACT

ABSTRACT compounding within a pharmacy, which is an integral part of quality management. A pharmacy that has not established standardized compounding procedures, which are important to ensuring that all preparations are of high quality, has created an environment within which errors will occur. The same applies to a pharmacy that has established standardized compounding procedures but employs pharmacists who do not have a common understanding of the standard operating procedures within their pharmacy.


Subject(s)
Drug Compounding/standards , Humans , Pharmacists
12.
Oncogene ; 34(30): 3968-76, 2015 Jul 23.
Article in English | MEDLINE | ID: mdl-25284585

ABSTRACT

Phosphatidylinositol 3-kinase (PI3K) promotes cancer cell survival, migration, growth and proliferation by generating phosphatidylinositol 3,4,5-trisphosphate (PIP3) in the inner leaflet of the plasma membrane. PIP3 recruits pleckstrin homology domain-containing proteins to the membrane to activate oncogenic signaling cascades. Anticancer therapeutics targeting the PI3K/AKT/mTOR (mammalian target of rapamycin) pathway are in clinical development. In a mass spectrometric screen to identify PIP3-regulated proteins in breast cancer cells, levels of the Rac activator PIP3-dependent Rac exchange factor-1 (P-REX1) increased in response to PI3K inhibition, and decreased upon loss of the PI3K antagonist phosphatase and tensin homolog (PTEN). P-REX1 mRNA and protein levels were positively correlated with ER expression, and inversely correlated with PI3K pathway activation in breast tumors as assessed by gene expression and phosphoproteomic analyses. P-REX1 increased activation of Rac1, PI3K/AKT and MEK/ERK signaling in a PTEN-independent manner, and promoted cell and tumor viability. Loss of P-REX1 or inhibition of Rac suppressed PI3K/AKT and MEK/ERK, and decreased viability. P-REX1 also promoted insulin-like growth factor-1 receptor activation, suggesting that P-REX1 provides positive feedback to activators upstream of PI3K. In support of a model where PIP3-driven P-REX1 promotes both PI3K/AKT and MEK/ERK signaling, high levels of P-REX1 mRNA (but not phospho-AKT or a transcriptomic signature of PI3K activation) were predictive of sensitivity to PI3K inhibitors among breast cancer cell lines. P-REX1 expression was highest in estrogen receptor-positive breast tumors compared with many other cancer subtypes, suggesting that neutralizing the P-REX1/Rac axis may provide a novel therapeutic approach to selectively abrogate oncogenic signaling in breast cancer cells.


Subject(s)
Breast Neoplasms/metabolism , Guanine Nucleotide Exchange Factors/physiology , MAP Kinase Signaling System , Receptors, Growth Factor/metabolism , Animals , Breast Neoplasms/pathology , Cell Survival , Feedback, Physiological , Female , Humans , MCF-7 Cells , Mice, Inbred NOD , Mice, SCID , Mutation , Neoplasm Transplantation , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , rac GTP-Binding Proteins/metabolism
13.
Int J Pharm Compd ; 18(6): 475-7, 2014.
Article in English | MEDLINE | ID: mdl-25906624

ABSTRACT

The healthcare system is vast in scope, with constant concerns of how the system's major changes will affect the quality of future patient care. This article concerns only one small corner of the healthcare system--pharmaceutical compounding. Despite our best efforts, we are not going to single-handedly change all of the grim statistics, no matter how many years we are given or how much assistance Americans obtain from their international colleagues. Yet, the "good" news is that although in my opinion the overall quality of America's healthcare system has declined, perhaps the modest niche of compounding pharmacy can become a role model of what actually works and can offer immense opportunities to improve the efficiency and effectiveness of health care.


Subject(s)
Drug Compounding/standards , Quality Control , Automobiles , Delivery of Health Care , Industry , Pharmacies
14.
Ir Med J ; 106(10): 302-5, 2013.
Article in English | MEDLINE | ID: mdl-24579409

ABSTRACT

We established a national audit to assess the thromboprophylaxis rate for venous thromoembolism (VTE) in at risk medical patients in acute hospitals in the Republic of Ireland and to determine whether the use of stickers to alert physicians regarding thromboprophylaxis would double the rate prophylaxis in a follow-up audit. 651 acute medical admission patients in the first audit and 524 in the second re-audit were recruited. The mean age was 66.5 yrs with similar numbers of male and female patients and 265 (22.6%) patients were active smokers. The first and second audits identified 549 (84%) and 487 (93%) of patients at-risk for VTE respectively. Of the at-risk patients, 163 (29.7%) and 132 (27.1%) received LMWH in the first and second audit respectively. Mechanical thromboprophylaxis was instigated in 75 (13.6%) patients in the first and 86 (17.7%) patients in the second audit. The placement of stickers in patient charts didn't produce a significant increase in the number of at risk patients treated in the second audit. There is unacceptably low adherence to the ACCP guidelines in Ireland and more complex intervention than chart reminders are required to improve compliance.


Subject(s)
Venous Thromboembolism/prevention & control , Aged , Female , Guideline Adherence , Humans , Ireland/epidemiology , Male , Medical Audit , Medical Staff, Hospital , Middle Aged , Practice Patterns, Physicians'/standards , Reminder Systems , Risk Assessment , Venous Thromboembolism/epidemiology
15.
Oncogene ; 29(15): 2272-80, 2010 Apr 15.
Article in English | MEDLINE | ID: mdl-20101222

ABSTRACT

Human chromosomal fragile sites are regions of the genome that are prone to DNA breakage, and are classified as common or rare, depending on their frequency in the population. Common fragile sites frequently coincide with the location of genes involved in carcinogenic chromosomal translocations, suggesting their role in cancer formation. However, there has been no direct evidence linking breakage at fragile sites to the formation of a cancer-specific translocation. Here, we studied the involvement of fragile sites in the formation of RET/PTC rearrangements, which are frequently found in papillary thyroid carcinoma (PTC). These rearrangements are commonly associated with radiation exposure; however, most of the tumors found in adults are not linked to radiation. In this study, we provide structural and biochemical evidence that the RET, CCDC6 and NCOA4 genes participating in two major types of RET/PTC rearrangements, are located in common fragile sites FRA10C and FRA10G, and undergo DNA breakage after exposure to fragile site-inducing chemicals. Moreover, exposure of human thyroid cells to these chemicals results in the formation of cancer-specific RET/PTC rearrangements. These results provide the direct evidence for the involvement of chromosomal fragile sites in the generation of cancer-specific rearrangements in human cells.


Subject(s)
Carcinoma, Papillary/genetics , Chromosome Fragile Sites/genetics , DNA Breaks , Oncogenes/genetics , Proto-Oncogene Proteins c-ret/genetics , Thyroid Gland/pathology , Thyroid Neoplasms/genetics , Aphidicolin/pharmacology , Base Sequence , Carcinoma, Papillary/pathology , Cell Line , Chromosome Fragile Sites/drug effects , DNA Breaks/drug effects , Humans , Introns/genetics , Molecular Sequence Data , Thyroid Gland/cytology , Thyroid Neoplasms/pathology , Translocation, Genetic/drug effects , Translocation, Genetic/genetics
16.
J Infus Nurs ; 31(2): 84-91, 2008.
Article in English | MEDLINE | ID: mdl-18344768

ABSTRACT

Intravenous catheter outcomes are a prominent topic for healthcare providers whose patients receive intravenous medications. There are thousands of products being marketed today claiming to improve catheter outcomes, thus improving overall patient outcomes and reducing provider costs associated with catheter infections and replacement. Catheter-related bloodstream infections (CR-BSIs) cost hospitals between $5000 and $34,000 per infection, and 12% to 25% of bloodstream infections are attributable to patient mortality. Products that claim to prevent CR-BSIs and subsequently reduce the number of bloodstream infections are a multimillion-dollar industry.


Subject(s)
Catheters, Indwelling/adverse effects , Extravasation of Diagnostic and Therapeutic Materials/etiology , Home Infusion Therapy/adverse effects , Phlebitis/etiology , Sepsis/etiology , Catheters, Indwelling/statistics & numerical data , Clinical Nursing Research , Equipment Failure/statistics & numerical data , Extravasation of Diagnostic and Therapeutic Materials/epidemiology , Extravasation of Diagnostic and Therapeutic Materials/prevention & control , Health Care Costs , Home Infusion Therapy/instrumentation , Home Infusion Therapy/nursing , Home Infusion Therapy/statistics & numerical data , Humans , Incidence , Infection Control/methods , Outcome Assessment, Health Care , Phlebitis/epidemiology , Phlebitis/prevention & control , Retrospective Studies , Risk Factors , Sepsis/epidemiology , Sepsis/prevention & control , Total Quality Management/organization & administration
20.
J Biomed Mater Res ; 58(2): 180-7, 2001.
Article in English | MEDLINE | ID: mdl-11241337

ABSTRACT

This study evaluated a porous tantalum biomaterial (Hedrocel) designed to function as a scaffold for osseous ingrowth. Samples were characterized for structure, Vickers microhardness, compressive cantilever bending, and tensile properties, as well as compressive and cantilever bending fatigue. The structure consisted of regularly arranged cells having struts with a vitreous carbon core with layers of CVI deposited crystalline tantalum. Microhardness values ranged from 240-393, compressive strength was 60 +/- 18 MPa, tensile strength was 63 +/- 6 MPa, and bending strength was 110 +/- 14 MPa. The compressive fatigue endurance limit was 23 MPa at 5 x 10(6) cycles with samples exhibiting significant plastic deformation. SEM examination showed cracking at strut junctions 45 degrees to the axis of the applied load. The cantilever bending fatigue endurance limit was 35 MPa at 5 x 10(6) cycles, and SEM examination showed failure due to cracking of the struts on the tension side of the sample. While properties were variable due to morphology, results indicate that the material provides structural support while bone ingrowth is occurring. These findings, coupled with the superior biocompatibility of tantalum, makes the material a candidate for a number of clinical applications and warrants further and continued laboratory and clinical investigation.


Subject(s)
Biocompatible Materials , Prostheses and Implants , Tantalum , Bone Remodeling , Humans , Orthopedic Fixation Devices
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