Frequency of asthma education in primary care in the years 2007-2010.

OBJECTIVE: Recent research suggests that health disparities persist among asthmatic patients and receipt of asthma education, though recent guidelines have highlighted the importance of receiving asthma education. The purpose of this study was to identify trends in the receipt of asthma education as well as to identify disparities in asthma education using the most recently available data in National Ambulatory Medical Care Survey, 2007-2010. METHODS: Weighted chi-square tests were conducted to identify associations between asthma education and variables of interest. A weighted multivariate logistic regression model was subsequently constructed to jointly assess the association of factors of interest on receipt of asthma education. Submission to the Campbell University Institutional Review Board resulted in expedited approval. RESULTS: The percentage of patients who receive asthma education remains quite low. After adjusting for all variables of interest: no statistically significant difference in receipt of asthma education between year groups (2007-2008, 2009-2010) was found (odds ratio [OR] 0.84, 95% confidence interval [CI] 0.52-1.34); patients seen by pediatricians (vs. internal medicine physicians) and Hispanic or Latino patients (vs. non-Hispanic or Latino patients) were more likely to receive asthma education (OR 2.72, 95% CI 1.11-6.66 and OR 2.33, 95% CI 1.18-4.60, respectively); and patients not prescribed a controller medication were less likely to receive asthma education than those who were (OR 0.56, 95% CI 0.37-0.82). CONCLUSIONS: Combined with previously published results, it appears the provision of asthma education continues to be low, despite proven benefits. Additionally, some patient and physician characteristics may be associated with the delivery of asthma education.

Nasal spreader grafts: a comparison of medpor to autologous tissue reconstruction.

Reconstruction of the damaged nasal vault is challenging. Limited available autologous tissue has lead surgeons to pursue alloplastic alternatives. A retrospective review comparing 18 patients who underwent secondary rhinoplasty with internal nasal valve reconstruction with spreader graft (SG) implants using either autologous tissue or high-density porous polyethylene (Medpor) was performed. All underwent bilateral SG reconstruction of the internal nasal valve with Medpor (10 cases) or autologous cartilage (8 cases). Mean follow-up was 26 months for the autologous group and 29 months for the Medpor group. Functional performance and aesthetic results were identical. Complications were few: 1 case of unilateral infection in the Medpor group treated with partial excision, and 1 case of erythema at the auricular donor site for the autologous tissue group. For patients who have exhausted autologous tissue options or are unwilling to tolerate potential donor-site morbidity, the Medpor SG is an appropriate option that allows for excellent aesthetic and functional results that remains stable over time.

The absorbable dermal staple device: a faster, more cost-effective method for incisional closure.

BACKGROUND: Closure with dermal sutures is time consuming, may increase the risks of inflammation and infection secondary to foreign body reaction, exposes the surgeon to possible needlestick injuries, and has variable cosmetic outcomes depending on each surgeon's technique. The absorbable INSORB dermal stapler is hypothesized to be faster and more cost effective than sutures for dermal layer closures and provides a safer and more consistent result. METHODS: This is a prospective, randomized, controlled study. Patients undergoing bilateral breast reconstruction with tissue expanders had one incision randomized to dermal closure with absorbable dermal staples. The contralateral side was closed with dermal sutures. During the expansion period, wounds were assessed by a blinded plastic surgeon using the 13-point Vancouver Scar Scale. At the time of implant exchange, both scars were excised and examined for histologic signs of inflammation. RESULTS: Eleven patients (22 incisions) were enrolled in the study. The dermal stapler was four times faster than standard suture closure, reducing closure time by 10.5 minutes (p

Gene therapy in skin: choosing the optimal viral vector.

Skin is an ideal gene therapy target because it is readily accessible and is involved in many pathologic processes. Viruses are the most common gene vectors, however, few comparative studies exist examining their efficacy in skin. This study evaluates adenovirus serotype 5, adeno-associated virus type 2 and 5, MMLV-derived retrovirus, and human immunodeficiency virus-1 derived lentivirus for gene vector activity in human dermal fibroblasts and other skin cell lines. Human immunodeficiency virus-1-based lentiviral vector resulted in over 90% transduction in all cell lines tested. Transduced cells maintained reporter expression over several passages after a single exposure. In contrast, gene activity fell rapidly over cell divisions with adenoviral and adeno-associated vectors. Therefore, lentiviral vectors are the delivery mechanism of choice for long-term therapeutic gene expression in dermal fibroblasts and other skin cell lines, whereas adenoviral or adeno-associated vectors may be preferred for short-term therapy.

A novel method for targeted gene therapy in ischemic tissues through viral transfection of an expression cassette containing multiple repetitions of hypoxia response element.

BACKGROUND: Increased levels of the transcription factor hypoxia inducible factor (HIF)-1 occur only in hypoxic tissue. The authors propose a therapeutic strategy that relies on HIF-1, the enhancer hypoxia response element (HRE), and the delivery vector adeno-associated virus-2 (AAV2) to direct ischemia specific gene therapy to skin. METHODS: An expression cassette containing the CMV promoter driving the reporter gene green fluorescent protein (GFP) was used to assess cutaneous tropism of AAV2. Transfection of dermal fibroblasts and immortalized keratinocytes (HaCat) was assessed with flow cytometry. Human embryonic kidney 293 (HEK) cells were used to produce vector stocks and test the authors' therapeutic strategy in quadruplicate. An expression cassette with nine repeats of HRE linked to beta-galactosidase (LacZ) within the AAV2 vector was constructed. HEK cells were transfected and exposed to normoxic (21% oxygen) and hypoxic (1% oxygen) conditions. LacZ activity was measured by conversion of galactoside red-beta-D-galactopyranoside. RESULTS: Approximately 50 percent of dermal fibroblasts and HaCat cells were transfected when treated with 1 x 10(4) genome copies/cell of AAV2-CMV-GFP. Using the same titration of AAV2-9HRE-LacZ, transfected HEK cells demonstrated LacZ activity of 0.496 +/- 0.068 U/microg in normoxia and 2.9 +/- 0.58 U/microg in hypoxia. Transfected cells exposed to 24 hours of hypoxia show greater than an 11-fold increase in LacZ activity (p < 0.05) compared with baseline normoxic controls. CONCLUSIONS: The authors' results confirm that AAV2 has in vitro tropism for skin-derived cell lines. Furthermore, HRE will drive gene expression in ischemia but not normoxia. This is the first step toward the authors' goal of HIF-1-regulated gene therapy to prevent ischemia related skin injury.

Platelet-derived growth factor B, but not fibroblast growth factor 2, plasmid DNA improves survival of ischemic myocutaneous flaps.

HYPOTHESIS: Tissue flaps are commonly used for surgical reconstruction, especially to cover difficult wounds and in breast reconstruction following mastectomy. Complications due to inadequate flap perfusion are a source of morbidity and, in the lower extremity, can result in amputation. SETTING: Laboratory. INTERVENTIONS: We evaluated the ability of platelet-derived growth factor (PDGF) B and fibroblast growth factor 2 plasmid DNA, formulated in a type I collagen matrix, to promote tissue survival in a rat transverse rectus abdominis muscle flap model based on the inferior deep epigastric vascular supply. In the absence of any therapeutic agent, only about 24% of flap tissue survives in this model. The DNA/matrix formulations were delivered subcutaneously into the skin paddles 7 days before flap elevation, and tissues were harvested 7 days later. RESULTS: Our studies reveal dramatic increases in overall vascularity after treatment with PDGF-B and fibroblast growth factor 2 plasmid DNA; however, only PDGF-B increased flap survival (130% increase at 228 micro g/cm(2) of plasmid DNA vs controls; P<.01). Transdermal spectral imaging demonstrated an increase in patent vessels supporting blood flow in flaps treated with PDGF-B plasmid DNA vs the fibroblast growth factor 2 transgene. CONCLUSION: Matrix-enabled gene therapy may provide an effective nonsurgical approach for promoting flap survival and is well suited for surgical applications in which transient therapeutic transgene expression is desired.

Use of hypoxia-inducible factor signal transduction pathway to measure O2 levels and modulate growth factor pathways.

Tissue PO2 levels are known to directly modulate numerous processes involved in the reparative response to cutaneous tissue injury, including cell differentiation and migration, extracellular matrix synthesis and maturation, and effectiveness of endogenous and exogenous growth factors. Oxygen is therefore likely the critical variable determining the healing capabilities of any tissue. Significant advances in the understanding of cutaneous wound healing progressed with advances in the measurement of tissue PO2, which has advanced over the past several decades from implantable probes to now include molecular tools such as the transcription factor hypoxia inducible factor-1 (HIF-1). HIF-1 modulates the expression of genes that drive the cellular adaptive response to hypoxia and possess the HIF-1 binding sequence named hypoxia response element within their promoter sequence. Molecular biology techniques are now allowing exploitation of the HIF-1/hypoxia response element pathway to drive the expression of potential vulnerary ectopic genes. Here we show the utility of the hypoxia response element for hypoxia-driven expression of the transforming growth factor-beta-signaling component Smad3 in vitro and the in vivo detection of ischemic hypoxia using luciferase. Smad3 is a positive effector of transforming growth factor-beta superfamily signal transduction. Such approaches are the latest evolution of work championed by Hunt and colleagues over the past 4 decades.

Growth factors in wound healing.

Enhancement of wound healing was limited to good surgical technique, maintenance of a clean wound with appropriate dressings, and debridement. The ability to heal wounds has been advanced through the recognition that healing in a moist environment is improved over that of a desiccated wound. Pharmacologic approaches to wound healing did not exist until the last few decades, when it was recognized that growth factors are normally present in the wound environment and that in animal models and a few clinical studies, the addition of growth factors could enhance healing. In 1998, platelet-derived growth factor was approved for clinical use. This approach is still the subject of intense investigation and clinical trials. This article analyzes current knowledge on growth factors as therapeutic agents and speculates on their future potential, with an analysis of successes and failures to date.