Isolation, characterization, and genetic manipulation of cold-tolerant, manganese-oxidizing Pseudomonas sp. strains.

Manganese-oxidizing bacteria (MnOB) produce Mn oxide minerals that can be used by humans for bioremediation, but the purpose for the bacterium is less clear. This study describes the isolation and characterization of cold-tolerant MnOB strains isolated from a compost pile in Morris, Minnesota, USA: Pseudomonas sp. MS-1 and DSV-1. The strains were preliminarily identified as members of species Pseudomonas psychrophila by 16S rRNA analysis and a multi-locus phylogenetic study using a database of 88 genomes from the Pseudomonas genus. However, the average nucleotide identity between these strains and the P. psychrophila sp. CF149 type strain was less than 93%. Thus, the two strains are members of a novel species that diverged from P. psychrophila. DSV-1 and MS-1 are cold tolerant; both grow at 4°C but faster at 24°C. Unlike the mesophilic MnOB P. putida GB-1, both strains are capable of robustly oxidizing Mn at low temperatures. Both DSV-1 and MS-1 genomes contain homologs of several Mn oxidation genes found in P. putida GB-1 (mnxG, mcoA, mnxS1, mnxS2, and mnxR). Random mutagenesis by transposon insertion was successfully performed in both strains and identified genes involved in Mn oxidation that were similar to those found in P. putida GB-1. Our results show that MnOB can be isolated from compost, supporting a role for Mn oxidation in plant waste degradation. The novel isolates Pseudomonas spp. DSV-1 and MS-1 both can oxidize Mn at low temperature and likely employ similar mechanisms and regulation as P. putida GB-1.IMPORTANCEBiogenic Mn oxides have high sorptive capacity and are strong oxidants. These two characteristics make these oxides and the microbes that make them attractive tools for the bioremediation of wastewater and contaminated environments. Identifying MnOB that can be used for bioremediation is an active area of research. As cold-tolerant MnOB, Pseudomonas sp. DSV-1 and MS-1 have the potential to expand the environmental conditions in which biogenic Mn oxide bioremediation can be performed. The similarity of these organisms to the well-characterized MnOB P. putida GB-1 and the ability to manipulate their genomes raise the possibility of modifying them to improve their bioremediation ability.

Quantification of nanoparticle release from polymer nanocomposite coatings due to environmental stressing.

Certain engineered nanoparticles (ENP) reduce the flammability of components used in soft furnishings (mattresses and upholstered furniture). However, because of the ENP's small size and ability to interact with biological molecules, these fire retardant ENPs may pose a health and environmental risks, if they are released sometime during the life cycle of the soft furnishing. Quantifying the released amount of these ENPs under normal end-use circumstances provides a basis for assessing their potential health and environmental impact. In this article, we report on efforts to identify suitable methodologies for quantifying the release of carbon nanofibers, carbon nanotubes, and sodium montmorillonites from coatings applied to the surfaces of barrier fabric and polyurethane foam. The ENPs released in simulated chewing and mechanical stressing experiments were collected in aqueous solution and quantified using Ultraviolet-Visible and inductively coupled plasma-optical emission spectroscopy. The microstructures of the released ENPs were characterized using scanning electron microscopy. The reported methodology and results provide important milestones to estimate the impact and toxicity of the ENP release during the life cycle of the nanocomposites. To our knowledge, this is the first study of ENP release from the soft furnishing coating, something that can be important application area for fire safety.

Routine Upright Imaging for Evaluating Degenerative Lumbar Stenosis: Incidence of Degenerative Spondylolisthesis Missed on Supine MRI.

STUDY DESIGN: A retrospective cohort. BACKGROUND: Degenerative spondylolisthesis (DS) with lumbar stenosis is a well-studied pathology and diagnosis is most commonly determined by a combination of magnetic resonance imaging (MRI) and standing radiographs. However, routine upright imaging is not universally accepted as standard in all practices. To the best of our knowledge, there has been no study investigating the incidence of missed diagnosis of DS evident only on standing lateral or dynamic radiographs when compared with sagittal alignment on MRI. OBJECTIVE: The authors hypothesize that supine MRI evaluation alone in lumbar degenerative disease will significantly underestimate the incidence of DS. Secondary hypothesis is that there will be no significant difference in detecting spondylolisthesis when comparing dynamic flexion-extension radiographs to standing lateral radiographs. METHODS: We retrospectively evaluated all patients presenting to spine clinic for degenerative lumbar conditions from July 2004 to July 2006 who had an MRI, upright lateral, and flexion-extension radiographs at our institution. The incidence of DS found on dynamic flexion-extension radiographs but not on MRI was determined. We then reviewed each and compared flexion-extension versus standing lateral views to determine whether there was any significant difference in detecting anterolisthesis. RESULTS: Of 416 patients with eligible studies, 109 were found to have DS at levels L4-L5, L5-S1, or L3-L4 based on flexion-extension radiographs. Of these, only 78 were found to have a corresponding spondylolisthesis on MRI, leaving 31/109 (28%) of DS levels undiagnosed on MRI. No additional anterolisthesis cases were detected on standing flexion-extension verses standing lateral radiographs. CONCLUSIONS: Routine standing lateral radiographs should be standard practice to identify DS, as nearly 1/3 of cases will be missed on supine MRI. This may have implications on whether or not an arthrodesis is performed on those patients requiring lumbar decompression. Flexion-extension radiographs demonstrated no added value compared with standing lateral x-rays for the purposes of diagnosing DS.

The use of vancomycin powder reduces surgical reoperation in posterior instrumented and noninstrumented spinal surgery.

BACKGROUND: Surgical site infections can complicate posterior spine surgery. Multiple hospital admissions may be required to adequately treat a surgical site infection, which is associated with increased costs and lower patient satisfaction. The objective of this study was to evaluate the efficacy of prophylactic intra-wound vancomycin powder in reducing the incidence of repeat surgery for infections after posterior instrumented and noninstrumented spine surgery. METHODS: A series of consecutive patients who underwent instrumented or noninstrumented posterior spine surgery for any indication by two surgeons from July 2010 to July 2012 were reviewed. The preoperative antibiotic regimens of both surgeons were identical, except that one surgeon applied 1 g vancomycin powder directly to the surgical bed before wound closure, while the other did not. Patient demographics, operative details, and rates of reoperation for wound infection in the control and the treatment groups were compared. RESULTS: Both the control group and treatment group consisted of 150 patients; mean ages were 58.33 and 54.14 years, respectively. Both groups had low rates of deep infection requiring surgical intervention. The treatment group had a significantly lower rate of infection requiring reoperation or surgical debridement (0 %; 95 % CI: 0 %-2.4 %) compared with the control group (4 %; 95 % CI: 1.5 %-8.5 %) (P = 0.0297). The six infections identified in the control group resulted in 12 repeat operative debridement procedures. Gram-positive organisms were identified in 66.7 % of infections. No complications were related to the application of vancomycin powder. CONCLUSIONS: The results of this study demonstrate that adjunctive vancomycin powder applied directly to the surgical bed before closure seems effective in preventing deep infections that require operative debridement following posterior spine surgery.

Community arts engagement supports perceptions of personal growth in older adults.

PURPOSE: The effects of arts engagement on older adults have been well-documented. However, the ways older adults overcome common situational and dispositional barriers to enhance personal growth and well-being are less known. METHODS: Fifty-six community dwelling older adults (71.3 ± 4.6 years) took part in dance, music, or a control workshop two times/week for ten weeks. Participants' personal growth was examined through focus groups and surveys in this mixed-methods study. RESULTS: Focus group and survey results revealed participants experienced personal growth through engaging in the dance and music arms of the experiment. Participants, especially those in arts workshops, described personal growth experiences aligning with four themes: increased social connections, developed new skills, utilized a growth mindset, and used creativity to overcome situational and dispositional barriers to participation. The barriers included musculoskeletal challenges, hearing impairments, and difficulty retaining new information. CONCLUSIONS: The study yielded high adherence and retention rates, and participants reported increased engagement within their communities. Our observations provide avenues for future practitioners and facilitators to create programming that empowers older adults and utilizes participants' ongoing feedback to support access, inclusion, and sense of community.

Implementation of CYP2C19 genotyping to guide proton pump inhibitor use at an academic health center.

PURPOSE: To describe the implementation of CYP2C19 testing into clinical practice at University of Florida (UF) Health Gainesville hospital to guide proton pump inhibitor (PPI) dosing and the lessons learned from this experience. SUMMARY: Different CYP2C19 genotypes are associated with variability in PPI plasma concentrations and intragastric pH, which may contribute to the risk of treatment failure due to subtherapeutic concentrations and adverse effects (eg, infection, bone fracture, renal dysfunction) with sustained supratherapeutic concentrations. Based on evidence available prior to the availability of pertinent Clinical Pharmacogenetics Implementation Consortium (CPIC) guidelines, the UF Health Precision Medicine Program (PMP) developed clinical recommendations, provided through automated alerts at the time of a PPI order, to (1) increase the PPI dose for individuals with genotypes linked to increased CYP2C19 enzyme activity (ie, rapid and ultrarapid metabolizers) to improve the likelihood of drug effectiveness and (2) decrease the dose for individuals with decreased CYP2C19 activity (ie, intermediate and poor metabolizers) to reduce the risk of harm. The CYP2C19-PPI implementation was an iterative process that taught us key implementation lessons. Most notably, physician engagement is essential, problem lists in the medical record are unreliable, and special populations (eg, pediatric patients) need to be considered. CONCLUSION: Guiding PPI prescribing based on CYP2C19 genotype is a practical approach to potentially improve the benefit-risk ratio with PPI therapy. Physician engagement is key for successful implementation. A CPIC guideline on CYP2C19 genotype-guided PPI dosing is now available, and automated alerts may be instituted to facilitate implementation.

Dance, Music, and Social Conversation Program Participation Positively Affects Physical and Mental Health in Community-Dwelling Older Adults: A Randomized Controlled Trial.

INTRODUCTION: As the world population ages, practitioners use community-engaged interventions to help older adults stay healthy. Engaging in arts programs (e.g., dance or music) reportedly improves physical and mental health, but little research exists examining these effects in community-dwelling older adults. Our purposes were to examine how taking part in 10-week, twice per week community arts programs (dance and music) and control (social conversation) affected physical and mental health in community-dwelling older adults and their perceptions after program participation.
Methods: In this randomized controlled trial, 64 older adults over 65 years of age (71.3 ± 4.6 years, 166.9 ± 8.3 cm, 78.1 ± 18.1 kg) took part in community-engaged arts programs: ballroom dance (n = 23), music (ukulele-playing, n = 17), or control (social conversation n = 24), two times per week for 10 weeks. Participants' physical health using the Short Physical Performance Battery (SPPB; score 0 = worst to 12 = best) and mental health using the Montreal Cognitive Assessment (MoCA; score = 0 to 30, where less than 26 = normal) were tested three times: 1. before (pre), 2. at the end of 10 weeks (post-1), and 3. 1 month after intervention (post-2). Separate 3 (group) x 3 (time) ANOVAs and adjusted Bonferroni pairwise comparisons as appropriate examined changes across groups and time. Focus group interviews and surveys were audio recorded, transcribed, and analyzed using inductive thematic analyses to examine participants' perceptions.
Results: Across all groups, participants had an 87.8% attendance and an 87.5% retention rate. Participants' SPPB performance improved over time (pre = 10.5 ± 1.4, post-1 = 10.7 ± 1.3, post-2 = 11.3 ± 1.0; p < 0.001), but similarly across groups (p = 0.40). Post-hoc analyses revealed that performance improved from pre to post-1 (p = 0.002) and pre to post-2 (p < 0.001). Participants' cognition improved over time (pre = 26.3 ± 2.8, post-1 = 27.3 ± 2.6, post-2 = 27.5 ± 2.5, p < 0.001), and similarly across groups (p = 0.60). Post-hoc analyses revealed that cognition improved from pre- to post-1 (p = 0.002), and pre- to post-2 (p = 0.001). Participants consistently mentioned increased social engagement as the major reason for participation.
Conclusions: Overall, taking part in community-engaged arts (dance and music) and social conversation programs positively influenced physical and mental health in older adults. Still, as all groups improved equally, the results may partly be due to participants having normal physical and mental function pre-participation and due to them learning the test over time. These study findings imply that providing fun and free community-engaged programs that empower participants to be more engaged can positively influence physical and mental health and promote successful aging in older adults.

Estimating the impact of the mattress fire safety Standard 16 CFR Part 1633 on bed fire outcomes.

Beds are a prevalent combustible in fatal fires in the United States effective 1 July 2007, the US Consumer Product Safety Commission promulgated a standard to severely reduce the heat release rate and the early heat output from mattresses and foundations when ignited by a flaming ignition source. This study estimates the Standard's success over its first decade using fire incidence, US population, and mattress sales data. The technique mitigates the influence of some exogenous factors that might have changed during this decade. The Standard is accomplishing its purpose, preventing approximately 65 fatalities (out of an estimated 95 fatalities in 2002-2005) from bed fires annually during 2015-2016, although not all pre-Standard mattresses had yet been replaced. Compared to residential upholstered furniture fires, which were not affected by the Standard, the numbers of bed fires decreased by 12%, injuries by 34%, and deaths by 82% between 2005-2006 and 2015-2016. Per bed fire, injuries decreased by 25% and fatalities decreased by 67%, indicating that the severity of bed fires is being reduced.

Success of junctional anterior cervical discectomy and fusion.

BACKGROUND CONTEXT: Junctional breakdown has long been a consideration for surgeons when performing an arthrodesis in the cervical spine. Numerous authors have reported symptomatic junctional disease after fusion with varying degrees of reoperation. To our knowledge, there are no large series recording the fusion rate using instrumentation as an adjuvant to bone grafting. PURPOSE: To determine the fusion rate when arthrodesis is performed in the setting of junctional stenosis using iliac crest autograft and instrumentation. STUDY DESIGN/SETTING: This is a retrospective review performed on patients at the senior author's institution. PATIENT SAMPLE: The patient population consisted of a consecutive series of patients undergoing an elective anterior-only cervical arthrodesis for junctional stenosis. OUTCOME MEASURES: The primary outcome is a physiologic measure from dynamic radiographs. Fusion was assessed by the absence of motion and radiolucent lines at the bone graft interface. METHODS: During the study period, a total of 56 consecutive patients underwent anterior treatment for junctional cervical stenosis. Forty-nine of these patients were treated with an anterior discectomy and instrumented arthrodesis using iliac crest autograft, and seven underwent a corpectomy. We retrospectively reviewed the patients' charts and radiographs to determine the fusion rate. RESULTS: A solid fusion was obtained in 81.6% of patients in the study group. In patients undergoing a single-level arthrodesis adjacent to a one-level fusion, the fusion rate was 95.2%. The fusion rate significantly dropped in patients with longer preexisting fusion segments. In patients with a two- or three-level fusions preoperatively, the union rate was 81.3% and 57.1%, respectively. CONCLUSIONS: Anterior cervical discectomy and arthrodesis yields a high fusion rate for cervical stenosis adjacent to a single-level fusion. A multilevel preexisting fusion segment leads to a significant decline in successfully achieving a solid adjacent fusion despite using iliac crest autograft and instrumentation.

Intraoperative somatosensory evoked potential monitoring during anterior cervical discectomy and fusion in nonmyelopathic patients--a review of 1,039 cases.

BACKGROUND CONTEXT: Intraoperative somatosensory evoked potential (SSEP) monitoring has been shown to reduce the incidence of new postoperative neurological deficits in scoliosis surgery. However, its usefulness during cervical spine surgery remains a subject of debate. PURPOSE: To determine the utility of intraoperative SSEP monitoring in a specific patient population (those with cervical radiculopathy in the absence of myelopathy) who underwent anterior cervical discectomy and fusion (ACDF) surgery. STUDY DESIGN: Retrospective review. PATIENT SAMPLE: A total of 1,039 nonmyelopathic patients who underwent single or multilevel ACDF surgery. The control group (462 patients) did not have intraoperative SSEP monitoring, whereas the monitored group (577 patients) had continuous intraoperative SSEP monitoring performed. OUTCOME MEASURE: A new postoperative neurological deficit. METHODS: SSEP tracings were reviewed for all 577 patients in the monitored group and all significant signal changes were noted. Medical records were reviewed for all 1,039 patients to determine if any new neurological deficits developed in the immediate postoperative period. RESULTS: None of the patients in the control group had any new postoperative neurological deficits. In the monitored group there were six instances of transient SSEP changes (1 due to suspected carotid artery compression; 5 thought to be due to transient hypotension) which resolved with the appropriate intraoperative intervention (repositioning of retractors; raising the arterial blood pressure). Upon waking up from anesthesia, one patient in the monitored group had a new neurological deficit (partial central cord syndrome) despite normal intraoperative SSEP signals. CONCLUSIONS: ACDF appears to be a safe surgical procedure with a low incidence of iatrogenic neurological injury. Transient SSEP signal changes, which improved with intraoperative interventions, were not associated with new postoperative neurological deficits. An intraoperative neurological deficit is possible despite normal SSEP signals.

Factors for Consideration in an Open-Flame Test for Assessing Fire Blocking Performance of Barrier Fabrics.

The main objective of the work reported here is to assess factors that could affect the outcome of a proposed open flame test for barrier fabrics (BF-open flame test). The BF-open flame test characterizes barrier effectiveness by monitoring the ignition of a flexible polyurethane foam (FPUF) layer placed in contact with the upper side of the barrier fabric, exposed to a burner flame from below. Particular attention is given to the factors that influence the ignitibility of the FPUF, including thermal resistance, permeability, and structural integrity of the barrier fabrics (BFs). A number of barrier fabrics, displaying a wide range of the properties, are tested with the BF-open flame test. Visual observations of the FPUF burning behavior and BF char patterns, in addition to heat flux measurements on the unexposed side of the barrier fabrics, are used to assess the protective performance of the BF specimen under the open flame test conditions. The temperature and heat transfer measurements on the unexposed side of the BF and subsequent ranking of BFs for their thermal protective performance suggest that the BF-open flame test does not differentiate barrier fabrics based on their heat transfer properties. A similar conclusion is reached with regard to BF permeability characterized at room temperature. However, the outcome of this BF-open flame test is found to be heavily influenced by the structural integrity of thermally degraded BF. The BF-open flame test, in its current form, only ignited FPUF when structural failure of the barrier was observed.

Smoldering and Flame Resistant Textiles via Conformal Barrier Formation.

A durable and flexible silicone-based backcoating (halogen free) is applied to the backside of an otherwise smoldering-prone and flammable fabric. When exposed to fire, cyclic siloxanes (produced by thermal decomposition of the backcoating) diffuse through the fabric in the gas phase. The following oxidation of the cyclic siloxanes forms a highly conformal and thermally stable coating that fully embeds all individual fibers and shields them from heat and oxidation. As a result, the combustion of the fabric is prevented. This is a novel fire retardant mechanism that discloses a powerful approach towards textiles and multifunctional flexible materials with combined smoldering/flaming ignition resistance and fire-barrier properties.

One-pot, bioinspired coatings to reduce the flammability of flexible polyurethane foams.

In this manuscript, natural materials were combined into a single "pot" to produce flexible, highly fire resistant, and bioinspired coatings on flexible polyurethane foam (PUF). In one step, PUF was coated with a fire protective layer constructed of a polysaccharide binder (starch or agar), a boron fire retardant (boric acid or derivative), and a dirt char former (montmorillonite clay). Nearly all coatings produced a 63% reduction in a critical flammability value, the peak heat release rate (PHRR). One formulation produced a 75% reduction in PHRR. This technology was validated in full-scale furniture fire tests, where a 75% reduction in PHRR was measured. At these PHRR values, this technology could reduce the fire threat of furniture from significant fire damage in and beyond the room of fire origin to being contained to the burning furniture. This flammability reduction was caused by three mechanisms-the gas-phase and condensed-phase processes of the boron fire retardant and the condensed-phase process of the clay. We describe the one-pot coating process and the impact of the coating composition on flammability.

Potential applications of image-guided radiotherapy for radiation dose escalation in patients with early stage high-risk prostate cancer.

Patients with early stage high-risk prostate cancer (prostate specific antigen > 20, Gleason score > 7) are at high risk of recurrence following prostate cancer irradiation. Radiation dose escalation to the prostate may improve biochemical-free survival for these patients. However, high rectal and bladder dose with conventional three-dimensional conformal radiotherapy may lead to excessive gastrointestinal and genitourinary toxicity. Image-guided radiotherapy (IGRT), by virtue of combining the steep dose gradient of intensity-modulated radiotherapy and daily pretreatment imaging, may allow for radiation dose escalation and decreased treatment morbidity. Reduced treatment time is feasible with hypo-fractionated IGRT and it may improve patient quality of life.

The use of computed tomography attenuation to evaluate osteoporosis following acute fractures of the thoracic and lumbar vertebra.

BACKGROUND: Relatively few patients have dual-energy x-ray absorptiometry to quantify the magnitude of bone loss as they age. Recent work correlates mean computed tomography (CT) attenuation in the level I (L1) vertebra with bone mineral density (BMD), making it possible to objectively evaluate the magnitude of bone loss in osteoporosis by this method. The aims of this study were to evaluate the utility of using CT scans in patients with acute thoracic and lumbar spine fractures to diagnose osteoporosis and using CT attenuation to evaluate the association between age and BMD. METHODS: We performed a retrospective study of patients with acute fractures of the thoracic or lumbar spine who had also undergone an abdominal (or L1) CT scan and compared mean CT attenuation in L1 against threshold values. We also compared differences in CT attenuation between younger (<65 years) and older (≥65 years) and older patients. RESULTS: A total of 124 patients were evaluated (74 thoracic and 50 lumbar fractures). Overall, there was a strong correlation between age and bone density as measured by CT attenuation (r = -.76). Among those with thoracic fractures (<65 years), mean CT attenuation was 196.51 HU. Forty-one patients were ≥65 years and had mean CT attenuation of 105.90 HU (P < .001). In patients with lumbar fractures, 27 patients were <65 years and had a mean CT attenuation of 192.26 HU and 23 patients were ≥65 years and had mean CT attenuation of 114.31 HU (P < .001). At the threshold of 110 HU, set for specificity, the magnitude of difference between the age-stratified cohorts was greater in the thoracic spine (P < .0001 vs P = .003). DISCUSSION: Using opportunistic CT, we demonstrate the relative frequency of osteoporosis in patients with acute fractures of the thoracic and lumbar spine and confirm that the association increases with age. The CT attenuation may provide a cheap and convenient method to help confirm a clinical diagnosis of osteoporosis in patients with fractures.

Rapid growing clay coatings to reduce the fire threat of furniture.

Layer-by-layer (LbL) assembly coatings reduce the flammability of textiles and polyurethane foam but require extensive repetitive processing steps to produce the desired coating thickness and nanoparticle fire retardant content that translates into a fire retardant coating. Reported here is a new hybrid bi-layer (BL) approach to fabricate fire retardant coatings on polyurethane foam. Utilizing hydrogen bonding and electrostatic attraction along with the pH adjustment, a fast growing coating with significant fire retardant clay content was achieved. This hybrid BL coating exhibits significant fire performance improvement in both bench scale and real scale tests. Cone calorimetry bench scale tests show a 42% and 71% reduction in peak and average heat release rates, respectively. Real scale furniture mockups constructed using the hybrid LbL coating reduced the peak and average heat release rates by 53% and 63%, respectively. This is the first time that the fire safety in a real scale test has been reported for any LbL technology. This hybrid LbL coating is the fastest approach to develop an effective fire retardant coating for polyurethane foam.

Cost savings analysis of intrawound vancomycin powder in posterior spinal surgery.

BACKGROUND CONTEXT: Recent studies have shown that prophylactic use of intrawound vancomycin in posterior instrumented spine surgery substantially decreases the incidence of wound infections requiring repeat surgery. Significant cost savings are thought to be associated with the use of vancomycin in this setting. PURPOSE: To elucidate cost savings associated with the use of intrawound vancomycin in posterior spinal surgeries using a budget-impact model. STUDY DESIGN: Retrospective cohort study. PATIENT SAMPLE: Data from a cohort of 303 patients who underwent spinal surgery (instrumented and noninstrumented) over 2 years were analyzed; 96 of these patients received prophylactic intrawound vancomycin powder in addition to normal intravenous (IV) antibiotic prophylaxis, and 207 received just routine IV antibiotic prophylaxis. Patients requiring repeat surgical procedures for infection were identified, and the costs of these additional procedures were elucidated. OUTCOME MEASURE: Cost associated with the additional procedure to remediate infection in the absence of vancomycin prophylaxis. METHODS: We retrospectively reviewed the cost of return procedures for treatment of surgical site infection (SSI). The total reimbursement received by the health care facility was used to model the costs associated with repeat surgery, and this cost was compared with the cost of a single local application of vancomycin costing about $12. RESULTS: Of the 96 patients in the treatment group, the return-to-surgery rate for SSI was 0. In the group without vancomycin, seven patients required a total of 14 procedures. The mean cost per episode of surgery, based on the reimbursement, the health care facility received was $40,992 (range, $14,459-$114,763). A total of $573,897 was spent on 3% of the 207-patient cohort that did not receive intrawound vancomycin, whereas a total of $1,152 ($12×96 patients) was spent on the cohort treated with vancomycin. CONCLUSIONS: This study shows a reduction in SSIs requiring a return-to-surgery-with large cost savings-with use of intrawound vancomycin powder. In our study population, the cost savings totaled more than half a million dollars.

Image-guided radiotherapy for cardiac sparing in patients with left-sided breast cancer.

Patients with left-sided breast cancer are at risk of cardiac toxicity because of cardiac irradiation during radiotherapy with the conventional 3-dimensional conformal radiotherapy technique. In addition, many patients may receive chemotherapy prior to radiation, which may damage the myocardium and may increase the potential for late cardiac complications. New radiotherapy techniques such as intensity-modulated radiotherapy (IMRT) may decrease the risk of cardiac toxicity because of the steep dose gradient limiting the volume of the heart irradiated to a high dose. Image-guided radiotherapy (IGRT) is a new technique of IMRT delivery with daily imaging, which may further reduce excessive cardiac irradiation. Preliminary results of IGRT for cardiac sparing in patients with left-sided breast cancer are promising and need to be investigated in future prospective clinical studies.

Feasibility of tomotherapy-based image-guided radiotherapy for locally advanced oropharyngeal cancer.

PURPOSE: The study aims to assess the feasibility of tomotherapy-based image-guided (IGRT) radiotherapy for locally advanced oropharyngeal cancer. A retrospective review of 33 patients undergoing concurrent chemoradiation for locally advanced oropharyngeal cancers was conducted. Radiotherapy planning, treatment toxicity and loco-regional control were assessed. RESULTS: At a median follow-up of 32 months (6-47 months), no patient developed loco-regional recurrence. Two patients (6%) developed distant metastases. Grade 3-4 acute toxicity was respectively 72% and 25% for mucositis and gastrointestinal toxicity. Two patients (6%) had long-term dependence on tube feedings. Dose-volume histogram demonstrated excellent target volume coverage and low radiation dose to the organs at risk for complications. CONCLUSIONS AND CLINICAL RELEVANCE: IGRT provides excellent loco-regional control but acute toxicity remains significant and needs to be addressed in future prospective trials. The feasibility of Tomotherapy to decrease radiation dose to the normal tissues merits further investigations.