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Imaging mass spectrometry (IMS) allows for visualization of the spatial distribution of proteins, lipids, and other metabolites in a targeted or untargeted approach. The identification of compounds through mass spectrometry combined with the mapping of compound distribution in the sample establishes IMS as a powerful tool for metabolomics. IMS analysis for serotonin will allow researchers to pinpoint areas of deficiencies or accumulations associated with ocular disorders such as serotonin selective reuptake inhibitor optic neuropathy. Furthermore, L-DOPA has shown great promise as a therapeutic approach for disorders such as age-related macular degeneration, and IMS allows for localization, and relative magnitudes, of L-DOPA in the eye. We describe here an end-to-end approach of IMS from sample preparation to data analysis for serotonin and L-DOPA analysis.

Various biomaterial technologies are promising for tissue engineering, including electrospinning, but commercial scale-up of throughput is difficult. The goal of the study was to evaluate meltblown fabrics as candidate scaffolds for rotator cuff tendon tissue engineering. Meltblown poly(lactic acid) fabrics were produced with several polymer crystallinities and airflow velocities [500(low), 900(medium) or 1400(high) m3air/h/m fabric]. Fiber diameter, alignment, and baseline bidirectional tensile mechanical properties were evaluated. Attachment and spreading of human adipose-derived stem cells (hASCs) were evaluated over 3 days immediately following seeding. After initial screening, the fabric with the greatest Young's modulus and yield stress was selected for 28-day in vitro culture and for evaluation of tendon-like extracellular matrix production and development of mechanical properties. As expected, airflow velocity of the polymer during meltblowing demonstrated an inverse relationship with fiber diameter. All fabrics exhibited fiber alignment parallel to the direction of collector rotation. All fabrics demonstrated mechanical anisotropy at baseline. Cells attached, proliferated, and spread on all fabrics over the initial three-day culture period. Consistent with the observed loss of integrity of the unseeded biomaterial, hASC-seeded scaffolds demonstrated a significant decrease in Young's modulus over 28 days of culture. However, dsDNA, sulfated glycosaminoglycan, and collagen content increased significantly over 28 days. Histology and polarized light microscopy demonstrated collagen deposition and alignment throughout the thickness of the scaffolds. While fiber diameters approximated an order of magnitude greater than those previously reported for electrospun scaffolds intended for tendon tissue engineering, they were still within the range of collagen fiber diameters found in healthy tendon. The extent of matrix production and alignment was similar to that previously observed for multilayered electrospun scaffolds. While the Young's modulus of scaffolds after 28 days of culture was lower than native rotator cuff tendon, it approximated that reported previously following culture of electrospun scaffolds and was on the same order of magnitude as of current Food and Drug Administration-approved patches for rotator cuff augmentation. Together, these data suggest that with minor polymer and parameter modifications, meltblown scaffolds could provide an economical, high-throughput production alternative method to electrospinning for use in rotator cuff tendon tissue engineering.

State governments periodically solicit, review, and award Safe Routes to Schools grants to local governments and school districts that are seeking to make improvements that will improve student travel to and from school. Having endured the process of identifying a worthy project and completing the grant application, these local entities must then execute the specified work. Many communities are successful, but some are not. The research presented in this paper identified promising practices used by those entities that had completed their projects (and had successfully achieved their goals) despite difficulties along the way. The research identified ways in which the grant fulfillment process broke down and how these difficulties may be overcome.

In this note we give various characterizations of random walks with possibly different steps that have relatively large discrepancy from the uniform distribution modulo a prime p, and use these results to study the distribution of the rank of random matrices over F_p and the equi-distribution behavior of normal vectors of random hyperplanes. We also study the probability that a random square matrix is eigenvalue-free, or when its characteristic polynomial is divisible by a given irreducible polynomial in the limit n to infinity in F_p. We show that these statistics are universal, extending results of Stong and Neumann-Praeger beyond the uniform model., 39 pages, typos corrected, title changed

A proposed measure of network cohesion for graphs arising from interrelated economic activity is studied. The measure is the largest singular value of a row-stochastic matrix derived from the adjacency matrix. It is shown here that among graphs on [math] vertices, the star universally gives the (strictly) largest measure. Other universal comparisons among graphs with larger measures are difficult to make, but one is conjectured, and a selection of empirical evidence is given.

The early Nd reflects the analysis of simple features of selectively attended auditory stimuli, but the precise nature of the more complex processing reflected by the late Nd is unclear. The late but not the early Nd is sensitive to interference from a concurrently presented visual spatial attention switching task. This experiment investigated whether the late Nd is also sensitive to deeper visual attention switching. Twenty-one subjects performed a dichotic listening task concurrently with either visual spatial or visual letter matching attention switching tasks. Late Nd amplitude was reduced by the spatial but not the letter matching task, indicating insensitivity to deeper attention switching. P300 amplitude was reduced by both tasks. Reductions in N100 and P200 were uncorrelated. We propose that, in part, the late Nd reflects an amodal memory trace containing spatial information, possibly involving a "where" rather than a "what" auditory pathway.

BACKGROUND AND OBJECTIVES: Despite numerous studies reporting an elevated risk of infant mortality among women who are obese, the magnitude of the association is unclear. A systematic review and meta-analysis was undertaken to assess the association between maternal overweight or obesity and infant mortality. METHODS: Four health care databases and gray literature sources were searched and screened against the protocol eligibility criteria. Observational studies reporting on the relationship between maternal overweight and obesity and infant mortality were included. Data extraction and risk of bias assessments were performed. RESULTS: Twenty-four records were included from 783 screened. Obese mothers (BMI ≥30) had greater odds of having an infant death (odds ratio 1.42; 95% confidence interval, 1.24–1.63; P < .001; 11 studies); these odds were greatest for the most obese (BMI >35) (odds ratio 2.03; 95% confidence interval, 1.61–2.56; P < .001; 3 studies). CONCLUSIONS: Our results suggest that the odds of having an infant death are greater for obese mothers and that this risk may increase with greater maternal BMI or weight; however, residual confounding may explain these findings. Given the rising prevalence of maternal obesity, additional high-quality epidemiologic studies to elucidate the actual influence of elevated maternal mass or weight on infant mortality are needed. If a causal link is determined and the biological basis explained, public health strategies to address the issue of maternal obesity will be needed.

The purpose of this study was to investigate the potential usefulness of single photon emission computed tomography (SPECT) bone scanning with technetium-99m methylene diphosphonate (Tc-99m MDP) in the diagnosis of idiopathic jaw pain. Unlike planar bone scanning, SPECT uses tomographic technology to provide 3-dimensional images, which are more useful in localizing small lesions.Twenty patients, each with a diagnosis of chronic idiopathic jaw pain, were compared after SPECT bone scanning with 20 age-matched and gender-matched normal controls. Uptake was identified and compared in sites with previously detected jaw pathoses and jaw pain.Nineteen of 20 patients with jaw pain evaluated with SPECT had positive scans, in contrast with 12 of 20 control subjects (P.04). Positive scans were correlated with painful sites in 15 of 20 patients, with the remaining 5 patients demonstrating no uptake in painful locations. Patients with jaw pain demonstrated 37 of 80 mouth quadrants with positive scans, in contrast with 21 of 80 mouth quadrants in the controls (P.01). Nineteen of 24 painful mouth quadrants had uptake in the pain group. Of the 21 quadrants positive in the controls, 17 were correlated with previously detected jaw pathoses. The sensitivity and specificity for detecting painful sites were 0.79 and 0.68, respectively. The sensitivity and specificity for detecting previously identified pathoses in the jaws of normal controls were 0. 80 and 0.93, respectively.Patients with idiopathic jaw pain had a significantly greater frequency of positive SPECT bone scans when compared with normal controls. However, the sensitivity and specificity of SPECT bone scans in detecting painful sites were low. These findings suggest that SPECT bone scanning with Tc-99m MDP is not indicated as a routine imaging procedure for the detection of jaw pathoses, but may be considered as a potential research tool in the future study of chronic idiopathic jaw pain.

Rhabdomyosarcoma is a neoplasm composed of striated muscle. One of the most common types of soft tissue mesenchymal tumors in infants, children, and adolescents, rhabdomyosarcoma was considered an almost uniformly fatal cancer as recently as 30 years ago. Presently a multimodal approach consisting of surgery, radiation, and chemotherapy has significantly improved the outlook for the patient with rhabdomyosarcoma. This article presents a case of intraoral rhabdomyosarcoma that was initially poorly controlled because of a lack of patient compliance. After proper treatment, the cancer went into remission. The patient remained cancer-free for 7 years, albeit with significant morbidity. This case demonstrates the significantly improved prognosis achieved with multimodal therapy.

This project brings together Bill Hsu's interactive improvisation system and Sean Meehan's unconventional approach to percussion.Hsu's system analyzes the real-time audio stream, extracts perceptually significant timbral features, and uses both timbral and gestural information to coordinate the behavior of a virtual ensemble of improvising agents. While the system is able to act autonomously and make (relatively) long-term decisions, a human operator may also influence the behavior of the virtual ensemble at a high level, in a manner similar to Butch Morris' conductions.Meehan uses an array of friction-related and other extended techniques on snare drum, cymbal and other drumkit elements to produce a rich and nuanced timbral palette. Hsu's system has been designed to work with saxophonist John Butcher; it will be enhanced and retuned to respond to Meehan's playing.

The early Nd reflects the analysis of simple features of selectively attended auditory stimuli, but the precise nature of the more complex processing reflected by the late Nd is unclear. The late but not the early Nd is sensitive to interference from a concurrently presented visual spatial attention switching task. This experiment investigated whether the late Nd is also sensitive to deeper visual attention switching. Twenty-one subjects performed a dichotic listening task concurrently with either visual spatial or visual letter matching attention switching tasks. Late Nd amplitude was reduced by the spatial but not the letter matching task, indicating insensitivity to deeper attention switching. P300 amplitude was reduced by both tasks. Reductions in N100 and P200 were uncorrelated. We propose that, in part, the late Nd reflects an amodal memory trace containing spatial information, possibly involving a "where" rather than a "what" auditory pathway.

Interferon-γ (IFN-γ) ± tumor necrosis factor-α (TNF-α) induces antiproliferation and intracellular Ca2+store depletion in a human submandibular ductal cell line (HSG), which can be reversed on cytokine removal [A. J. Wu, G. C. Chen, B. J. Baum, and I. S. Ambudkar. Am. J. Physiol. 270 ( Cell Physiol. 39): C514–C521, 1996]. Here we have examined a possible mechanism for the IFN-γ-induced intracellular Ca2+store depletion. There was a time-dependent decrease in thapsigargin-dependent internal Ca2+release after exposure of the cells to the cytokines. The intracellular Ca2+pump [sarco(endo)plasmic reticulum Ca2+-ATPase (SERCA)] protein in lysates and membranes of cells treated with IFN-γ ± TNF-α, but not with TNF-α alone, showed a similar time-dependent decrease (examined using a SERCA2 antibody). Removal of the cytokines, which resulted in recovery of cell growth and refill of internal Ca2+stores, also increased the level of SERCA protein. The decrease in SERCA is not a result of decreased cell proliferation, since thapsigargin, 2,5-di-( t-butyl)-1,4-hydroquinone, or serum-free growth conditions induced antiproliferative effects on HSG cells without any corresponding decrease in SERCA. We suggest that the IFN-γ-induced decrease in the level of SERCA accounts for the depleted state of internal Ca2+stores in cytokine-treated HSG cells. These data suggest a novel mechanism for the inhibition of HSG cell growth by IFN-γ.

Susceptibility to bleeding in the patient treated with coumarin derivatives poses difficult management issues for the dentist. Classic monitoring for anticoagulation relied on the prothrombin time, but reagent variability issues have caused the emergence of the International Normalized Ratio (INR) as an alternative, and possibly more reliable, laboratory test for the assessment of a patient's anticoagulation status. The literature suggests that an INR range of 1.5 to 2.5 represents the most appropriate level of anticoagulation for the surgical patient. That is, at this INR, some protection is afforded against thrombo-embolic events without significantly sacrificing effective post-operative hemostasis. Since the patient with an INR value within the recommended range is still anticoagulated, he/she is still at risk for post-operative bleeding. Adherence to local hemostatic measures--such as pressure, topical thrombin, alveolar-placed resorbable sponges, and primary wound closure--offers the patient important adjunctive protection against post-operative bleeding.

A common sequela of certain malignancies is nonbacterial thrombotic endocarditis (NBTE), a phenomenon in which sterile fibrin/ platelet aggregates are deposited onto normal cardiac valves. These verrucae represent a predisposing factor for the initiation of infective endocarditis following a bacteremia. This paper presents a case history which is highly suggestive of infective endocarditis which occurred as a result of multiple odontogenic abscesses in a patient with Hodgkin's lymphoma. The case illustrates the important role that the dentist can play in the management of cancer patients and emphasizes a wholistic concept of medical care in which the dentist is an integral member of the health-care team.

The patient who presents to the physician with a history of facial pain can be a diagnostic challenge. The etiology can be elusive, and this problem is compounded by the subjective nature and the often multi-factorial causes of facial pain. The differential diagnoses to be considered include both local and systemic disorders such as neuropathy, myofascial pain, dentoalveolar pathoses, and psychological disturbances, among others. This paper presents the case of a patient with a history of left auricular pain that was managed for over 12 years with drug therapy with only limited success. A thorough head and neck evaluation revealed probable myofascial pain with a poorly occluding set of complete dentures as a potential etiology. Fabrication of a new set of dentures and modification of the patient's denture-wearing habits has produced an almost complete remission of the pain. This case demonstrates the importance of a dental consultation to rule out a possible oral-musculoskeletal and/or dental etiology in the management of the patient with facial pain.

It has been shown that cellular migration, persistence, and associated cytoskeletal arrangement are highly dependent on substrate stiffness (modulus: N/m2 and independent of geometry), but little is known on how cells respond to subtle changes in local geometry and structural stiffness (N/m). Here, using fibers of varying diameter (400, 700, and 1200 nm) and length (1 and 2 mm) deposited over hollow substrates, we demonstrate that single mouse C2C12 cells attached to single suspended fibers form spindle morphologies that are sensitive to fiber mechanical properties. Over a wide range of increasing structural stiffness (2 to 100+ mN/m), cells exhibited decreases in migration speed and average nucleus shape index of ∼57% (from 58 to 25 μm/h) and ∼26% (from 0.78 to 0.58), respectively, whereas the average paxillin focal-adhesion-cluster (FAC, formed at poles) length increased by ∼38% (from 8 to 11 μm). Furthermore, the increase in structural stiffness directly correlates with cellular persistence, with 60% of cells moving in the direction of increasing structural stiffness. At similar average structural stiffness (25 ± 5 mN/m), cells put out longer FAC lengths on smaller diameters, suggesting a conservation of FAC area, and also exhibited higher nucleus shape index and migration speeds on larger-diameter fibers. Interestingly, cells were observed to deform fibers locally or globally through forces applied through the FAC sites and cells undergoing mitosis were found to be attached to the FAC sites by single filamentous tethers. These varied reactions have implications in developmental and disease biology models as they describe a strong dependence of cellular behavior on the cell’s immediate mechanistic environment arising from alignment and geometry of fibers.