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Detecting biomarkers at pg/ml concentrations or below is, in many situations, critical for quantifying levels in healthy individuals as well as the changes that can occur in the progression of disease states. The ability to detect multiple biomarkers from the same sample allows for better diagnoses, more efficient testing, and lower volumes of sample required. Based on single molecule counting technology, a multiplex instrument was designed and built that is capable of detecting cytokines and other low-abundance proteins at sub-pg/ml quantities in human plasma samples. The multiplex single molecule counting instrument was used to generate 95% reference limits for interleukin 4 (IL-4

Background The aim of this study was to evaluate nocturia severity and nocturia-related differences in sleep, daytime symptoms and functional performance among patients with stable heart failure (HF). Methods and Results In this cross-sectional observational study, we recruited 173 patients [mean age 60.3 ± 16.8 years; female n = 60 (35%); mean left ventricular ejection fraction 32 ± 14.6%] with stable chronic HF from HF disease management programs in the northeastern United States. Participants reported nocturia and completed a 6-minute walk test (6MWT), 1 night of ambulatory polysomnography, and the SF-36 Medical Outcomes Study, Epworth Sleepiness, Pittsburgh Sleep Quality Index, Multidimensional Assessment of Fatigue, and Centers for the Epidemiological Studies of Depression scales. Participants reported 0 (n = 30; 17.3%), 1–2 (n = 87; 50.2%), and ≥3 (n = 56; 32.4%) nightly episodes of nocturia. There were decreases in sleep duration and efficiency, REM and stage 3–4 sleep, physical function, and 6MWT distance and increases in the percentage of wake time after sleep onset, insomnia symptoms, fatigue, and sleepiness across levels of nocturia severity. Conclusions Nocturia is common, severe, and closely associated with decrements in sleep and functional performance and increases in fatigue and sleepiness in patients with stable HF.

We demonstrate that a biomimetic polymer network is capable of affecting bone regeneration in vivo. Starting with a foundation consisting of an environmentally responsive poly(N-isopropylacrylamide-co-acrylic acid) hydrogel, we incorporated matrix metalloproteinase-13 (MMP-13) degradable crosslinkers and peptides containing integrin-binding domains (i.e., Arg-Gly-Asp) to create a biomimetic matrix designed to encourage osteoblast migration and proliferation. We independently tuned matrix stiffness and peptide concentration to generate a response surface model of osteoblast proliferation on different types of matrices. Osteoblast proliferation was significantly influenced by matrix stiffness (i.e., its complex modulus) and peptide concentration. When implanted in a rat femoral ablation model, these matrices induced bone regeneration only when protease degradable crosslinks were used to create the network. For the matrices with MMP-13 degradable crosslinkers, the bone formed had a trabecular-like structure and was distributed throughout the marrow space. Based on the correlated effects of matrix stiffness and ligand concentration, the response surface model will facilitate improvements in the regenerative capacity of these artificial extracellular matrices.

A simple fluorescence based characterization method was developed to assess ligand density on peptide-modified biomaterials. The method exploits the exquisite sensitivity of proteolysis for the purpose of liberating a fluorescently labeled probe fragment from an immobilized peptide. The released fragment can then be detected in solution using high-throughput fluorometry. In silico screening tools identified the enzyme chymotrypsin as a promising candidate for releasing a detectable probe fragment from the fluorescently labeled peptide, Ac-CGGNGEPRGDTYRAYK(FITC)GG-NH(2). After chymotrypsin digestion of the peptide in solution was first characterized using mass spectrometry and HPLC, a basic enzyme mediated release protocol was developed and implemented to generate peptide-binding isotherms on various peptide-modified biomaterials. The new method is sensitive, has good signal-to-noise ratio (S/N), and is easily standardized. Furthermore, the technique can be applied independent of material chemistry and geometry, making it a suitable alternative to radiolabeling for a wide range of biomaterial applications.

Thermoresponsive and injectable semi-interpenetrating polymer networks (sIPNs) containing a biospecific cell-adhesive signal and proteolytically degradable domains were developed as a synthetic equivalent of the extracellular matrix (ECM). The sIPNs synthesized define a modular hydrogel ECM where different properties of the matrix can be manipulated independently, thus creating a system where parametric analysis of the effect of hydrogel properties on cell proliferation and differentiation is possible. sIPNs composed of poly(N-isopropylacrylamide-co-acrylic acid) [p(NIPAAm-co-AAc)] and RGD-grafted poly(acrylic acid) linear chains [p(AAc)-g-RGD] were synthesized with peptide crosslinkers containing a matrix metalloproteinase-13 (MMP-13, collagenase-3) degradable domain. The lower critical solution temperature (LCST) of peptide-crosslinked p(NIPAAm-co-AAc) sIPNs was not influenced by the addition of either linear p(AAc) or peptide-modified p(AAc) chains ( approximately 34 degrees C) in PBS. Degradation of peptide-crosslinked hydrogels and sIPNs was enzyme specific and concentration dependent. Exposure of rat calvarial osteoblast (RCO) culture to the degradation products from the peptide-crosslinked hydrogels did not significantly affect cell viability. Migration of RCOs into the sIPNs was dependent upon the presence of both a cell-adhesive RGD peptide (Ac-CGGNGEPRGDTYRAY-NH2) and proteolytically-degradable crosslinks; however, there was greater dependence on the latter. The sIPNs synthesized are versatile materials for assessing cell fate in synthetic ECM constructs in vitro and tissue regeneration in vivo.

Concerns about the efficacy of ethanol disinfection for implanted biomaterials prompted investigation of an alternative sterilization process, ultraviolet irradiation, for terminal sterilization of N-isopropylacrylamide-based hydrogels containing biomimetic peptides. Ultraviolet irradiation is more easily applied on a laboratory scale than gamma irradiation or electron beam, two commercially utilized methods; thus, UVC irradiation was investigated as a low-cost sterilization procedure that might be performed in laboratories prior to in vivo studies. UVC irradiation at 400 muW/cm(2) for up to 15 h did not prevent growth of Escherichia coli within the hydrogels, while ethanol disinfection did prevent growth for the duration of the experiment (120 h). Furthermore, UVC irradiation caused progressive degradation of peptides containing the Arg-Gly-Arg (RGD) domain. UVC irradiation cannot be used as a terminal sterilization process for peptide-modified materials. The system used in this study is not intended to be adequate for evaluating the sterility of medical devices in accordance with current Good Manufacturing Practice (cGMP); however, it remains a useful, low-cost system for the preliminary evaluation of sterilization procedures in terms of their ability to eliminate pathogenic organisms while preserving the structure of biologically active molecules within in a laboratory setting. Ethanol treatment is still the preferred method for disinfection of bioactive materials containing peptides or UV-degradable groups.

Background and Objectives: Pain in hospitalized children may be underrecognized and undertreated. The objective of this survey was to benchmark pain prevalence, intensity, assessment, and pharmacologic as well as integrative treatment of pain in inpatients in a US children’s hospital. Methods: This was a single-day, cross-sectional survey and electronic medical record review of inpatients who received medical care at a pediatric hospital. Inpatients and emergency department patients were asked to report their experience with pain and its management during the previous 24 hours. Results: Of 279 inpatients listed on the morning census, 178 children and parents were located and completed the survey. Seventy-six percent had experienced pain during the previous 24 hours, usually acute or procedural pain, 12% of whom possibly suffered from chronic pain. Twenty percent of all children surveyed experienced moderate and 30% severe pain in that time period. The worst pain reported by patients was caused by needle pokes (40%), followed by trauma/injury (34%). Children and their parents rated 5 integrative, nonpharmacologic modalities as more effective than medications. Pain assessments and management were documented in the medical record for 58% of patients covering the 24-hour period before the morning census. The most commonly prescribed analgesics were acetaminophen, morphine, and ibuprofen. Conclusions: Despite existing hospital policies and a pain consult team, significant room for improvement in pain management was identified. A hospital-wide, 3-year Lean quality improvement initiative on reducing pain was commenced as a result of this survey.

High-throughput biology has been pioneered by genomics through the application of robotics to expedite DNA-sequencing projects. Advances in high-throughput protein methods are needed to drive the protein production line for high-throughput structural and functional analysis of newly discovered genes. This will require the development and application of a variety of recombinant-protein expression systems to produce the diversity of proteins from both humans and model organisms.

Saliva is a supersaturated solution with respect to hydroxyapatite, the main inorganic component of tooth enamel. Several acidic phosphoproteins are present in saliva which allow the supersaturated state to be maintained without random crystallization occurring. Statherin is the only salivary protein currently known to inhibit both the primary and secondary precipitation of hydroxyapatite in the supersaturated environment of saliva. To identify the residues of statherin that are necessary to control biomineralization, a recombinant form of human statherin was produced from Escherichia coli using a yeast intein fusion construct. The primary structure of the recombinant statherin was characterized by SDS-PAGE, N-terminus sequencing, MALDI mass spectrometry, and amino acid analysis and found to have the expected values relative to human-derived statherin. The secondary structure of the recombinant statherin was investigated by circular dichroism spectroscopy, which revealed the predominant presence of random coil in phosphate-buffered saline solution, with a higher propensity toward alpha helicity in 100% TFE. This increase in helicity in 100% TFE was also found in statherin that was synthesized by solid-phase synthesis. These results demonstrate that human statherin can be produced in a recombinant form which behaves comparably to the natural form.

Advanced registered nurse practitioners (ARNP) are becoming a mainstay in primary and acute care settings because of the changes in the health care environment. Acute care hospitals are recognizing the need to provide expert clinical care in a holistic manner, which requires communication and recognition of the patient and patient’s needs as central to the care delivered. Patients with neurological acute care needs or injuries are often at high risk for fragmented care due to their complexity and rehabilitation needs. The goal of this demonstration project was to develop a more proactive, patient- focused care delivery model. Outcome data assessed included: influence of the ARNP on the discharge process, patient satisfaction, management structure, and enhancement of critical thinking by staff.

Parkinson's disease, a chronic incurable disorder, has a significant impact on quality of life. Parkinson's disease results from chronic degeneration of cells in the basal ganglia that produce dopamine. It typically affects elderly individuals producing muscle rigidity and akinesia. Traditionally, Parkinson's disease has been controlled by medications. However, for some patients, medications may no longer be effective, or may produce drug-related complications. For this group of patients, pallidotomy is gaining support as an intervention to control the debilitating symptoms of Parkinson's disease, thus enabling a person to perform everyday tasks. Although the procedure was developed in the 1950s, contemporary technology has allowed a resurgence of the intervention. With the focus on relief of two of the major symptoms of Parkinson's disease, the pallidotomy procedure is gaining support as a surgical intervention for this disease. Therefore, it is important for the health care team to have an understanding of the disease process, surgical intervention and postoperative care to enhance quality outcomes for this patient population.

Spinal cord stimulation (SCS) became available in the 1970s as a treatment option for patients with constant or recurring pain. This invasive procedure is performed after all other efforts have failed to prove effective in controlling pain. Advanced technology enables the patient to perform adjustments to maximize comfort with the use of a magnet or portable programmer. Nursing care is guided by a specific plan of care for the SCS patient population. A patient population-specific standard may be useful.

1. IntroductionOverview: Array-Based Proteomics The key advantage to array-based methods for protein study is the parallel analysis of samples in a high-throughput fashion. Similar to the DNA microarray, this approach requires miniaturization technologies, high sample throughput, and automation. Arraybased methods for protein analysis afford a high-throughput format by which to screen protein‐protein, protein‐DNA, and protein‐small molecule interactions and provides important functional information for newly identified genes that are derived from genome projects. Protein arrays hold the potential to identify these interactions as well as provide a means for differential expression and protein profiling between different cell types.

Proteins found in mineralized tissues act as nature’s crystal engineers, where they play a key role in promoting or inhibiting the growth of minerals such as hydroxyapatite (bones/teeth) and calcium oxalate (kidney stones). Despite their importance in hard-tissue formation and remodeling, and in pathological processes such as stone formation and arterial calcification, there is little known of the protein structure-function relationships that govern hard-tissue engineering. Here we review early studies that have utilized solid-state NMR (ssNMR) techniques to provide in situ secondary-structure determination of statherin and statherin peptides on their biologically relevant hydroxyapatite (HAP) surfaces. In addition to direct structural study, molecular dynamics studies have provided considerable insight into the protein-binding footprint on hydroxyapatite. The molecular insight provided by these studies has also led to the design of biomimetic fusion peptides that utilize nature’s crystal-recognition mechanism to display accessible and dynamic bioactive sequences from the HAP surface. These peptides selectively engage adhesion receptors and direct specific outside-in signaling pathway activation in osteoblast-like cells.

Many important matrix proteins involved in bone remodeling contain separate domains that orient the protein on hydroxyapatite and interact with target cell receptors, respectively. We have designed two synthetic peptides that mimic the dual activities of these large, complex proteins by binding to calcium phosphate minerals and by engaging integrin-dependent signaling pathways in osteoblasts. The addition of either PGRGDS from osteopontin or PDGEA from collagen type I to the HAP-binding domain of statherin (N15 domain) did not alter its alpha-helical structure or diminish its affinity for hydroxyapatite. Immobilized N15-PGRGDS bound MC3T3-E1 osteoblasts predominantly via the alpha v beta 3 integrin and induced focal adhesion kinase (FAK) phosphorylation at comparable levels to immobilized osteopontin. Immobilized N15-PDGEA bound MC3T3-E1 osteoblasts predominantly through the alpha 2 beta 1 integrin and induced similar levels of FAK phosphorylation. Although both peptides induced FAK phosphorylation with similar time courses, only the N15-PDGEA peptide induced ERK1/2 phosphorylation, showing that these peptides are also capable of engaging integrin-specific signaling pathways. This peptide system can be used to study adhesion-dependent control of signaling in the context of the relevant biomineral surface and may also be useful in biomaterial and tissue engineering applications.

Summary form only given. We are working to develop a variety of biomaterials that are designed to communicate with biomolecules, cells, and tissues. Here we report the joint use of protein engineering and microfabrication approaches to generate surfaces that control cell phenotype in confined dimensions on device surfaces, and the solid-state NMR characterization of peptide and protein conformation on hydroxyapatite and hydrophobic biomaterial surfaces that interact with cell surface receptors.

Monitoring patients' temperatures is an important aspect of clinical nursing. In surgical areas, we rely on accurate temperature readings to determine appropriate therapy. Various body sites have been used for temperature measurement: oral, axillary, rectal, and tympanic. Oral temperature readings have long been considered the gold standard. However, oral temperature readings may be contraindicated, depending on surgical incision and level of consciousness or in cases of seizure. Tympanic temperature monitoring is often the next choice. The literature supports the accuracy of tympanic monitoring; however, some clinicians have questioned its accuracy. This study used a repeated-measures design to determine the reproducibility of tympanic and oral temperature measurements. A difference of 0.2 degrees C was considered clinically significant. Outcome data indicated that variability was similar with oral and tympanic temperatures. There was no significant difference between average tympanic and average oral temperatures. Therefore, this study supports the use of tympanic thermometers in addition to oral thermometers in obtaining temperatures.

Physical restraints have been the standard of practice to manage certain types of patient behavior, such as unstable mobility, wandering, agitation, and interference with medical treatment. However, this intervention is not without serious negative consequences. Patients with neurological disorders or injuries are often at high risk for being restrained. The need to change to a more positive, patient-focused, restraint-free model was the goal of this project. A convenience sample of adult patients who were admitted to a neurological unit were studied. Outcome data that were assessed included (1) staff nurses' perception of restraints, (2) fall rate, (3) fall rate with injury, and (4) tube/line loss rate. Staff perceptions of restraints were assessed by administering the Perception of Restraints Use Questionnaire (PRUQ) before and after implementation of the restraint-reduced environment. The results of the outcome data support the change to a more restraint-reduced environment, as indicated by fall rate, fall rate with injury, and tube/line loss. Additionally, nurses' perceptions of restraints, as measured by the PRUQ, indicated a trend toward less emphasis on the use of restraints to control specific unsafe or undesirable patient behaviors.

The resection of a pituitary tumor represents a challenging diagnosis for the critical care nurse. There are important nursing assessments that can assist in identifying post-surgical complications. Detailed teaching instructions by the critical care nurses will also assist in minimizing the patient's postoperative complications.

Cerebral vasospasm presents a challenge for the nursing staff. To date, no effective prevention methods have been identified. The key to decreasing the mortality rates is in discovering a method of preventing or reversing the arterial narrowing caused by vasospasm. The nurse needs to be aware of the theories of vasospasm and the rationale for treatment. Neurologic assessment skills are important for the nurse to detect minimal changes that may indicate vasospasm. Nurses who are informed will be able to provide optimal care to patients with cerebral vasospasm and provide the necessary support for family members. Drug therapy continues to be the first-line defense in treating vasospasm. Nimodipine is a very promising drug with demonstrated effectiveness to reduce the neurologic deficits caused by vasospasm. Further research on the treatment of vasospasm following SAH is currently in progress.