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1.
J Hum Nutr Diet ; 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38739733

RESUMO

BACKGROUND: This survey described the compensation of neonatal intensive care unit (NICU) registered dietitian nutritionists (RDNs) in the United States and examined correlates of higher salaries within this group. METHODS: A cross-sectional online survey was completed in 2021 by 143 NICU RDNs from 127 US hospitals who reported hourly wage in US dollars (USD). We used initial bivariate analyses to assess the relationship of selected institution-level and individual-level variables to hourly wage; the rank-sum test for binary variables; bivariate regression and Pearson correlation coefficients for continuous variables; the Kruskal-Wallis test for categorical variables. Variables with a compelling relationship to the hourly wage outcome were considered in model creation. Final model selection was based on comparisons of model fit. RESULTS: Median hourly compensation was USD 33.24 (interquartile range [IQR] 29.81, 38.49). Seven variables had a compelling bivariate relationship with hourly wage: cost of living, employer facility with a paediatric residency, employer facility with a neonatal fellowship, NICU bed: full-time equivalents (FTE) RDN ratio, years in neonatal nutrition, having a certification and order writing privileges. In the final adjusted model (R2 = 0.42), three variables remained associated with increased hourly wage: higher cost of living, longer length of career in neonatal nutrition and fewer NICU beds per NICU RDN FTE. CONCLUSIONS: US NICU RDNs earn similar or slightly higher wages than other US paediatric RDNs; they earn substantially less than other NICU healthcare team members. Employers need to improve compensation for NICU RDNs to incentivise their retention and recognise their additional non-clinical responsibilities.

2.
Adv Nutr ; : 100220, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38670164

RESUMO

Adequate nutrition is necessary for achieving optimal growth and neurodevelopment. Growth is a natural and expected process that happens concomitantly with rapid advancements in neurodevelopment. Serial weight, length, and head circumference growth measures are essential for monitoring development, although identifying pathological deviations from normal growth can pose challenges. Appropriate growth assessments require considerations that a range of sizes for length, head circumference, and weight are expected and appropriate. Because of genetic differences and morbidities, there is a considerable overlap between the growth of healthy infants and those with growth alterations. Parents tend to be over-concerned about children who plot low on growth charts and often need reassurance. Thus, the use of terms such as "poor" growth or growth "failure" are discouraged when growth is approximately parallel to growth chart curves even if their size is smaller than specific percentiles. No specific percentile should be set as a growth goal; individual variability should be expected. An infant's size at birth is important information that goes beyond the common use of prognostic predictions of appropriate compared with small or large for gestational age. The lower the birthweight, the lower the nutrient stores and the more important the need for nutrition support. Compared to term infants, preterm infants at term-equivalent age have a higher percentage of body fat, but this diminishes over the next months. Current research findings support expert recommendations that preterm infants should grow, after early postnatal weight loss, similar to the fetus and then term-born infants, which translates to growth approximately parallel to growth chart curves. There is no need for a trade-off between optimum cognition and optimum future health. Each high-risk infant needs individualized nutrition and growth assessments. This review aims to examine infant growth expectations and messaging for parents of preterm and term-born infants within the broader causal framework.

3.
Clin Perinatol ; 50(3): 743-762, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37536776

RESUMO

Neonatal registered dietitian nutritionists (RDNs) are critical members of the neonatal intensive care unit (NICU) team due to their unique skillset of growth assessment, nutrition evaluation, and implementation of nutrition best practices. There is a paucity of data on appropriate staffing of neonatal RDNs in NICUs to promote improved patient outcomes. Here, the authors describe current neonatal RDN staffing and responsibilities in the US NICUs.


Assuntos
Nutricionistas , Recém-Nascido , Humanos , Unidades de Terapia Intensiva Neonatal
4.
Am J Clin Nutr ; 117 Suppl 1: S87-S105, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37173062

RESUMO

Human milk is the ideal source of nutrition for most infants, but significant gaps remain in our understanding of human milk biology. As part of addressing these gaps, the Breastmilk Ecology: Genesis of Infant Nutrition (BEGIN) Project Working Groups 1-4 interrogated the state of knowledge regarding the infant-human milk-lactating parent triad. However, to optimize the impact of newly generated knowledge across all stages of human milk research, the need remained for a translational research framework specific to the field. Thus, with inspiration from the simplified environmental sciences framework of Kaufman and Curl, Working Group 5 of the BEGIN Project developed a translational framework for science in human lactation and infant feeding, which includes 5 nonlinear, interconnected translational stages, T1: Discovery; T2: Human health implications; T3: Clinical and public health implications; T4: Implementation; and T5: Impact. The framework is accompanied by 6 overarching principles: 1) Research spans the translational continuum in a nonlinear, nonhierarchical manner; 2) Projects engage interdisciplinary teams in continuous collaboration and cross talk; 3) Priorities and study designs incorporate a diverse range of contextual factors; 4) Research teams include community stakeholders from the outset through purposeful, ethical, and equitable engagement; 5) Research designs and conceptual models incorporate respectful care for the birthing parent and address implications for the lactating parent; 6) Research implications for real-world settings account for contextual factors surrounding the feeding of human milk, including exclusivity and mode of feeding. To demonstrate application of the presented translational research framework and its overarching principles, 6 case studies are included, each illustrating research gaps across all stages of the framework. Applying a translational framework approach to addressing gaps in the science of human milk feeding is an important step toward the aligned goals of optimizing infant feeding across diverse contexts as well as optimizing health for all.


Assuntos
Lactação , Leite Humano , Feminino , Lactente , Humanos , Aleitamento Materno , Fenômenos Fisiológicos da Nutrição do Lactente , Saúde Pública
5.
Semin Fetal Neonatal Med ; 27(5): 101392, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36137922

RESUMO

Human milk's variable macronutrient composition is a necessary consideration when caring for very low birthweight infants. Targeted fortification is the practice of fortifying human milk using its known composition from human milk analysis, rather than its assumed macronutrient values. Utilization of human milk analyzers to measure the protein, fat, lactose, and energy composition within human milk samples has allowed the translation of this practice into the clinical setting. This review discusses the rationale of why targeted fortification is an important practice, what barriers exist in its implementation in the clinical setting, and what research gaps remain to be addressed.


Assuntos
Recém-Nascido Prematuro , Leite Humano , Recém-Nascido , Lactente , Humanos , Alimentos Fortificados/análise , Recém-Nascido de muito Baixo Peso , Fenômenos Fisiológicos da Nutrição do Lactente
6.
Clin Perinatol ; 49(2): 355-379, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35659091

RESUMO

Prematurity and other complications at birth are nutritional emergencies. Parenteral nutrition is a bridge to enteral nutrition for a few days or months, and sometimes the sole source of nutrition for life. Parenteral nutrition regimens are constructed to provide adequate and balanced energy, macronutrients, and micronutrients to support growth and prevent deficiencies. Neonatal parenteral nutrition regimens are complicated by periodic shortages of essential products, compatibility challenges, and contaminants. Newborns benefit from serial growth assessments, monitoring of biochemical status, nutrition-focused physical examinations, and management by a multidisciplinary team to ensure adequacy of parenteral nutrition and promote best outcomes.


Assuntos
Doenças do Prematuro , Nutrição Parenteral , Nutrição Enteral , Humanos , Recém-Nascido , Micronutrientes , Nutrição Parenteral Total
7.
JPEN J Parenter Enteral Nutr ; 45(8): 1673-1682, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34638161

RESUMO

BACKGROUND: Parenteral nutrition (PN) is essential to support premature infants' growth and varies with enteral nutrition (EN) advancement rates. Data on PN duration's impact on premature infants' growth are limited. The aim of this multicenter observational study was to determine the effect of early PN duration on body composition at term corrected gestational age (CGA) in very low-birth-weight (VLBW) premature infants. METHODS: VLBW infants exposed to PN in the first week of life and exposed to significantly different EN regimens were divided into two groups on the basis of early PN duration. Infants with a birth weight (BW) <1000 g and PN duration <28 days and infants with a BW 1000-1500 g and PN duration <14 days were assigned to the "short-PN" group. Infants receiving PN for longer durations were assigned to the "long-PN" group. Body composition was assessed via air displacement plethysmography at term CGA or before discharge. RESULTS: Sixty-two and 53 infants were assigned to the short-PN and long-PN groups, respectively. The two groups were significantly different in BW and GA, so a nested case-control study was conducted after matching 36 infant pairs. Infants in the long-PN group had significantly lower fat-free mass (FFM) z-scores, but both groups had comparable fat mass (FM) z-scores. Long PN was a significant negative predictor of FFM z-score in the multivariate regression analysis. CONCLUSION: In VLBW premature infants, PN duration is negatively associated with FFM z-scores at term CGA without affecting FM z-scores.


Assuntos
Recém-Nascido de muito Baixo Peso , Nutrição Parenteral , Composição Corporal , Estudos de Casos e Controles , Humanos , Lactente , Recém-Nascido , Recém-Nascido Prematuro
8.
Front Nutr ; 8: 692600, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34540876

RESUMO

Introduction: Human milk (HM) is the ideal enteral feeding for nearly all infants and offers unique benefits to the very low birthweight (VLBW) infant population. It is a challenge to meet the high nutrient requirements of VLBW infants due to the known variability of HM composition. Human milk analysis (HMA) assesses the composition of HM and allows for individualized fortification. Due to recent U.S. Food and Drug Administration (FDA) approval, it has relatively recent availability for clinical use in the US. Aim: To identify current practices of HMA and individualized fortification in neonatal intensive care units (NICUs) across the United States (US) and to inform future translational research efforts implementing this nutrition management method. Methods: An institutional review board (IRB) approved survey was created and collected data on the following subjects such as NICU demographics, feeding practices, HM usage, HM fortification practices, and HMA practices. It was distributed from 10/30-12/21/2020 via online pediatric nutrition groups and listservs selected to reach the intended audience of NICU dietitians and other clinical staff. Each response was assessed prior to inclusion, and descriptive analysis was performed. Results: About 225 survey responses were recorded during the survey period with 119 entries included in the analysis. This represented 36 states and Washington D.C., primarily from level III and IV NICUs. HMA was reported in 11.8% of responding NICUs. The most commonly owned technology for HMA is the Creamatocrit Plus TM (EKF Diagnostics), followed by the HM Analyzer by Miris (Uppsala, Sweden). In NICUs practicing HMA, 84.6% are doing so clinically. Discussion: Feeding guidelines and fortification of HM remain standard of care, and interest in HMA was common in this survey. Despite the interest, very few NICUs are performing HMA and individualized fortification. Barriers identified include determining who should receive individualized fortification and how often, collecting a representative sample, and the cost and personnel required. Conclusions: Human milk analysis and individualized fortification are emerging practices within NICUs in the US. Few are using it in the clinical setting with large variation in execution among respondents and many logistical concerns regarding implementation. Future research may be beneficial to evaluate how practices change as HMA and individualized fortification gain popularity and become more commonly used in the clinical setting.

9.
Clin Nutr ESPEN ; 43: 212-222, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34024517

RESUMO

Nutritional management is integral to infant care in the neonatal intensive care unit (NICU). Recent research on body composition that specifically evaluated fat and fat-free mass has improved our understanding of infant growth and nutritional requirements. The need for body composition monitoring in infants is increasingly recognized as changes in fat mass and fat-free mass associated with early growth can impact clinical outcomes. With the availability of air displacement plethysmography (ADP) as a noninvasive method for assessing infant body composition and published normative gestational age- and sex-specific body composition curves, it is justifiable to integrate this innovation into routine clinical care. Here we describe our experiences in implementing body composition measurement using ADP in routine clinical care in different NICU settings.


Assuntos
Unidades de Terapia Intensiva Neonatal , Pletismografia , Composição Corporal , Feminino , Idade Gestacional , Humanos , Lactente , Recém-Nascido , Masculino , Fluxo de Trabalho
10.
Neonatal Netw ; 38(1): 7-16, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30679251

RESUMO

Expressed breast milk (EBM) is the gold standard of infant nutrition, but is not always available for use for preterm infants in the NICU setting. Donor breast milk (DBM) is often a preferred alternative for preterm and very low birth weight (VLBW) infants when maternal milk is not available. This article discusses the composition of DBM, reviews its advantages compared to formula, discusses challenges related to its long-term use, and identifies strategies to utilize DBM in the context of total nutritional management of preterm and VLBW infants. We will use a framework of WHO, WHAT, WHERE, WHEN, and WHY to answer the questions: who gets DBM, why use DBM, where does DBM come from, what is in DBM, and when may DBM use be challenged.


Assuntos
Fórmulas Infantis , Recém-Nascido Prematuro , Recém-Nascido de muito Baixo Peso , Bancos de Leite Humano , Leite Humano , Administração dos Cuidados ao Paciente/métodos , Feminino , Humanos , Fórmulas Infantis/análise , Fórmulas Infantis/química , Fenômenos Fisiológicos da Nutrição do Lactente , Recém-Nascido , Recém-Nascido Prematuro/crescimento & desenvolvimento , Recém-Nascido Prematuro/fisiologia , Doenças do Prematuro/prevenção & controle , Recém-Nascido de muito Baixo Peso/crescimento & desenvolvimento , Recém-Nascido de muito Baixo Peso/fisiologia , Masculino , Bancos de Leite Humano/organização & administração , Bancos de Leite Humano/normas , Leite Humano/química , Leite Humano/fisiologia
11.
Cureus ; 9(10): e1753, 2017 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-29226043

RESUMO

The complicated nature of neurological diseases-and the importance of accurate diagnosis and treatment for patient quality of life-have made the need for more advanced imaging techniques more urgent than ever. Automated whole brain tractography promises to increase the knowledge that neurologists have of a variety of disease processes, including schizophrenia, age-related changes to white matter, brain tumors, and epilepsy.

12.
J Sch Health ; 87(5): 376-387, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28382672

RESUMO

BACKGROUND: Sustainable school buildings hold much promise to reducing operating costs, improve occupant well-being and, ultimately, teacher and student performance. However, there is a scarcity of evidence on the effects of sustainable school buildings on health and performance indicators. We sought to create a framework for a multidisciplinary research agenda that links school facilities, health, and educational outcomes. METHODS: We conducted a nonsystematic review of peer review publications, government documents, organizational documents, and school climate measurement instruments. RESULTS: We found that studies on the impact of physical environmental factors (air, lighting, and thermal comfort) on health and occupant performance are largely independent of research on the social climate. The current literature precludes the formation of understanding the causal relation among school facilities, social climate, occupant health, and occupant performance. CONCLUSIONS: Given the average age of current school facilities in the United States, construction of new school facilities or retrofits of older facilities will be a major infrastructure investment for many municipalities over the next several decades. Multidisciplinary research that seeks to understand the impact of sustainable design on the health and performance of occupants will need to include both an environmental science and social science perspective to inform best practices and quantification of benefits that go beyond general measures of costs savings from energy efficiencies.


Assuntos
Poluição do Ar/prevenção & controle , Conservação dos Recursos Naturais , Saúde Ambiental/organização & administração , Arquitetura de Instituições de Saúde/normas , Doenças Profissionais/prevenção & controle , Instituições Acadêmicas/organização & administração , Exposição Ambiental , Humanos
13.
Cureus ; 9(2): e1018, 2017 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-28348937

RESUMO

The current healthcare system in the United States (US) is characterized by high costs and poor patient outcomes. A value-based healthcare system, centered on providing the highest quality of care for the lowest cost, is the country's chosen solution for its healthcare crisis. As the US transitions to a value-based model, a new definition of health is necessary to clearly define what constitutes a healthy state. However, such a definition is impossible to develop without a proper understanding of what "health" actually means. To truly understand its meaning, one must have a thorough historical understanding of the changes in the concept of health and how it has evolved to reflect the beliefs and scientific understanding of each time period. Thus, this review summarizes the changes in the definition of health over time in order to provide a context for the definition needed today. We then propose a new definition of health that is specifically tailored to providers working in the era of value-based care.

14.
J Healthc Risk Manag ; 34(1): 28-36, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25070254

RESUMO

Healthcare reform efforts have resulted in expanded creation of integrated organizations such as accountable care organizations. These ACOs, however, create additional risk management issues for organizations in terms of antitrust compliance, fraud and abuse, and medical liability issues. While much has been written on the formation of such organizations, the postformation risks have not been explored adequately. This article summarizes some of the risk-management challenges that ACOs and other integrated organizations may face.


Assuntos
Organizações de Assistência Responsáveis/legislação & jurisprudência , Organizações de Assistência Responsáveis/normas , Credenciamento , Prestação Integrada de Cuidados de Saúde/legislação & jurisprudência , Prestação Integrada de Cuidados de Saúde/normas , Gestão de Riscos/legislação & jurisprudência , Gestão de Riscos/normas , Leis Antitruste , Segurança Computacional , Registros Eletrônicos de Saúde , Medicina Baseada em Evidências , Fraude , Humanos , Responsabilidade Legal , Imperícia , Estados Unidos
15.
J Bone Joint Surg Am ; 94(15): 1406-15, 2012 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-22854994

RESUMO

BACKGROUND: Implant-associated infections contribute to patient morbidity and health care costs. We hypothesized that surface modification of titanium fracture hardware with vancomycin would support bone-healing and prevent bacterial colonization of the implant in a large-animal model. METHODS: A unilateral transverse mid-diaphyseal tibial osteotomy was performed and repaired with a titanium locking compression plate in nine sheep. Four control animals were treated with an unmodified plate and five experimental animals were treated with a vancomycin-modified plate. The osteotomy was inoculated with 2.5 × 106 colony-forming units of Staphylococcus aureus. The animals were killed at three months postoperatively, and implants were retrieved aseptically. Microbiologic and histologic analyses, scanning electron and confocal microscopy, and microcomputed tomography were performed. RESULTS: All animals completed the study. Compared with the treatment cohort, control animals exhibited protracted lameness in the operatively treated leg. Gross findings during necropsy were consistent with an infected osteotomy accompanied by a florid and lytic callus. Microcomputed tomography and histologic analysis of the tibiae further supported the presence of septic osteomyelitis in the control cohort. Thick biofilms were also evident, and bacterial cultures were positive for Staphylococcus aureus in three of four control animals. In contrast, animals treated with vancomycin-treated plates exhibited a healed osteotomy site with homogenous remodeling, there was no evidence of biofilm formation on the retrieved plate, and bacterial cultures from only one of five animals were positive for Staphylococcus aureus. CONCLUSIONS: Vancomycin-derivatized plate surfaces inhibited implant colonization with Staphylococcus aureus and supported bone-healing in an infected large-animal model.


Assuntos
Biofilmes/efeitos dos fármacos , Infecções Relacionadas à Prótese/prevenção & controle , Infecções Estafilocócicas/prevenção & controle , Tíbia/cirurgia , Vancomicina/farmacologia , Cicatrização/efeitos dos fármacos , Animais , Aderência Bacteriana/efeitos dos fármacos , Placas Ósseas , Materiais Revestidos Biocompatíveis , Modelos Animais de Doenças , Microscopia Eletrônica de Varredura , Osteotomia , Carneiro Doméstico , Staphylococcus aureus/efeitos dos fármacos , Células-Tronco/efeitos dos fármacos , Propriedades de Superfície , Titânio , Microtomografia por Raio-X
16.
Antimicrob Agents Chemother ; 55(2): 487-94, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21098245

RESUMO

Infection is an important medical problem associated with the use of bone allografts. To retard bacterial colonization, we have recently reported on the modification of bone allografts with the antibiotic vancomycin (VAN). In this report, we examine the ability of this antibiotic-modified allograft to resist bacterial colonization and biofilm formation. When antibiotic was coupled to the allograft, a uniform distribution of the antibiotic was apparent. Following challenges with Staphylococcus aureus for 6 h, the covalently bonded VAN decreased colonization as a function of inoculum, ranging from 0.8 to 2.0 log(10) CFU. Furthermore, the VAN-modified surface resisted biofilm formation, even in topographical niches that provide a protected environment for bacterial adhesion. Attachment of the antibiotic to the allograft surface was robust, and the bonded VAN was stable whether incubated in aqueous media or in air, maintaining levels of 75 to 100% of initial levels over 60 days. While the VAN-modified allograft inhibited the Gram-positive S. aureus colonization, in keeping with VAN's spectrum of activity, the VAN-modified allograft was readily colonized by the Gram-negative Escherichia coli. Finally, initial toxicity measures indicated that the VAN-modified allograft did not influence osteoblast colonization or viability. Since the covalently tethered antibiotic is stable, is active, retains its specificity, and does not exhibit toxicity, it is concluded that this modified allograft holds great promise for decreasing bone graft-associated infections.


Assuntos
Antibacterianos/farmacologia , Transplante Ósseo , Osso e Ossos/química , Osso e Ossos/microbiologia , Staphylococcus aureus/crescimento & desenvolvimento , Vancomicina/farmacologia , Antibacterianos/química , Aderência Bacteriana/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Contagem de Colônia Microbiana , Humanos , Microscopia Confocal , Osteoblastos/citologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/fisiologia , Vancomicina/química
17.
Bone ; 48(3): 631-8, 2011 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-21035576

RESUMO

Bacterial contamination of bone allograft is a significant complication of orthopedic surgery. To address this issue, we have engineered a method for covalently modifying bone allograft tissue with the antibiotic vancomycin. The goal of this investigation was to compare the biocidal properties of this new allograft material with those of vancomycin physisorbed onto graft material. The duration of antibiotic release from the vancomycin-modified allograft matrix was determined, and no elution was observed. In contrast, the adsorbed antibiotic showed a peak elution at 24h that then decreased over several days. We next used an Staphylococcus aureus disk diffusion assay to measure the activity of the eluted vancomycin. Again we found that no active antibiotic was eluted from the covalently modified allograft. Similarly, when the vancomycin-modified allograft morsel was used in the assay, no measurable elution was observed; amounts of antibiotic released from the adsorbed samples inhibited S. aureus growth for 4-7 days. Probably the most telling property of the allograft was that after 2 weeks, the tethered allograft was able to resist bacterial colonization. Unlike the elution system in which vancomycin was depleted over the course of days-weeks, the antibiotic on the allograft was stably bound even after 300 days, while its biocidal activity remained undiminished for 60 days. This finding was in stark contrast to the antibiotic impregnated allograft, which was readily colonized by bacteria. Finally we chose to evaluate three indicators of cell function: expression of a key transcription factor, expression of selected transcripts, and assessment of cell morphology. Since the tethered antibiotic appeared to have little or no effect on any of these activities, it was concluded that the stable, tethered antibiotic prevented bacterial infection while not modifying bone cell function.


Assuntos
Antibacterianos/farmacologia , Transplante Ósseo , Vancomicina/farmacologia , Adsorção/efeitos dos fármacos , Antibacterianos/química , Biomarcadores/metabolismo , Diferenciação Celular/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Células Cultivadas , Contagem de Colônia Microbiana , Estabilidade de Medicamentos , Feto/citologia , Fluorescência , Perfilação da Expressão Gênica , Humanos , Testes de Sensibilidade Microbiana , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Fenótipo , Fatores de Tempo , Transplante Homólogo , Vancomicina/química
18.
Clin Orthop Relat Res ; 468(8): 2113-21, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20361282

RESUMO

BACKGROUND: Bone grafts are frequently used to supplement bone stock and to establish structural stability. However, graft-associated infection represents a challenging complication leading to increased patient morbidity and healthcare costs. QUESTIONS/PURPOSES: We therefore designed this study to (1) determine if increasing initial S. aureus inoculation of bone allograft results in a proportionate increase in colonization; (2) assess if antibiotics decrease colonization and if antibiotic tethering to allograft alters its ability to prevent bacterial colonization; and (3) determine if covalent modification alters the allograft topography or its biological properties. METHODS: Allograft bone and vancomycin-modified bone (VAN-bone) was challenged with different doses of S. aureus for times out to 24 hours in the presence or absence of solution vancomycin. Bacterial colonization was assessed by fluorescence, scanning electron microscopy (SEM), and by direct colony counting. Cell density and distribution of osteoblast-like cells on control and modified allograft were then compared. RESULTS: Bacterial attachment was apparent within 6 hours with colonization and biofilm formation increasing with time and dose. Solution vancomycin failed to prevent bacterial attachment whereas VAN-bone successfully resisted colonization. The allograft modification did not affect the attachment and distribution of osteoblast-like cells. CONCLUSIONS: Allograft bone was readily colonized by S. aureus and covered by a biofilm with especially florid growth in natural topographic niches. Using a novel covalent modification, allograft bone was able to resist colonization by organisms while retaining the ability to allow adhesion of osteoblastic cells. CLINICAL RELEVANCE: Generation of allograft bone that can resist infection in vivo would be important in addressing one of the most challenging problems associated with the use of allograft, namely infection.


Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Transplante Ósseo , Próteses e Implantes/microbiologia , Staphylococcus aureus/efeitos dos fármacos , Vancomicina/farmacologia , Antibacterianos/química , Substitutos Ósseos , Técnicas In Vitro , Infecções Relacionadas à Prótese/prevenção & controle , Infecções Estafilocócicas/prevenção & controle , Staphylococcus aureus/crescimento & desenvolvimento , Transplante Homólogo , Vancomicina/química
19.
Tissue Eng Part A ; 16(6): 2041-9, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20109017

RESUMO

Infection associated with inert implants is complicated by bacterial biofilm formation that renders the infection antibiotic insensitive. The goal of this investigation was to synthesize and characterize a vancomycin (VAN)-modified bone allograft that could render the tissue inhospitable to bacterial colonization and the establishment of infection. We found that the numbers of primary amines, which could serve as anchors for chemical synthesis, increased with limited demineralization. Using these amines, we coupled two linkers and VAN to bone using Fmoc chemistry. By immunohistochemistry, VAN was abundant on the surface of the allograft; based on elution and measurement of bound antibody, this coupling yielded at least approximately 26 ng VAN/mg bone. The coupled VAN appeared to be permanently bound to the allograft, as it showed no elution in a disk diffusion assay, and, importantly, resisted colonization by Staphylococcus aureus challenges. We suggest that this chimeric construct represents a new generation of antibiotic-modified allografts that provide antibacterial properties.


Assuntos
Antibacterianos/farmacologia , Alicerces Teciduais/química , Transplante Homólogo/métodos , Vancomicina/farmacologia , Aminas/química , Antibacterianos/química , Humanos , Imuno-Histoquímica , Microscopia Confocal , Espectrofotometria Atômica , Staphylococcus aureus/efeitos dos fármacos , Vancomicina/química
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