Regime change in the recorder: Using Navier-Stokes modeling to design a better instrument

Blowing a recorder at a low to moderate blowing speed with the toneholes all closed yields the lowest note in the range of the instrument. As the blowing speed is increased, the tone abruptly changes to the tone an octave higher. This "jump" in the frequency of the dominant spectral component of the tone is referred to as "regime change." Interestingly, in conversations with recorder players, several have mentioned that regime change seems to occur at a significantly lower blowing speed for bass recorders than for instruments that sound an octave or more higher. In this paper we study regime change in the recorder and use Navier-Stokes modeling to confirm and study differences in the behavior of different instruments in the recorder family. We show, using modeling, how the regime change threshold in a model of the bass recorder can be increased by changing the geometry in the vicinity of the labium. These results are then confirmed through experimental studies of real recorders with designs inspired by the modeling results. The insights gained from these results suggest new recorder designs that may produce instruments that in some respects are more playable than current instruments.

Combining robotics with enhanced serotonin-driven cortical plasticity improves post-stroke motor recovery

Despite recent progresses in robotic rehabilitation technologies, their efficacy for post-stroke motor recovery is still limited. Such limitations might stem from the insufficient enhancement of plasticity mechanisms, crucial for functional recovery. Here, we designed a clinically relevant strategy that combines robotic rehabilitation with chemogenetic stimulation of serotonin release to boost plasticity. These two approaches acted synergistically to enhance post-stroke motor performance. Indeed, mice treated with our combined therapy showed substantial functional gains that persisted beyond the treatment period and generalized to non-trained tasks. Motor recovery was associated with a reduction in electrophysiological and neuroanatomical markers of GABAergic neurotransmission, suggesting disinhibition in perilesional areas. To unveil the translational potentialities of our approach, we specifically targeted the serotonin 1A receptor by delivering Buspirone, a clinically approved drug, in stroke mice undergoing robotic rehabilitation. Administration of Buspirone restored motor impairments similarly to what observed with chemogenetic stimulation, showing the immediate translational potential of this combined approach to significantly improve motor recovery after stroke.

Navier-Stokes-based model of the clarinet

A model of a single reed instrument is studied in which the reed is described as an Euler-Bernoulli beam, and the air flow through the instrument is calculated using the Navier-Stokes equations. The hypothetical instrument resembles a clarinet, but is smaller than a real clarinet to keep the numerical modeling feasible on available supercomputers. This article explores the conditions under which the frequency of the reed oscillations and the emitted sound are determined by the resonant frequency of the bore of the instrument. The effect of the contact between the reed and the player's lips is also studied, and quantitative results for the air density and pressure in the mouthpiece and throughout the instrument bore are also presented.

SAT0293 EXOSOMES DERIVED FROM PLASMA OF SYSTEMIC SCLEROSIS (SSC) PATIENTS AND FROM SSC CULTURED FIBROBLASTS CONTAIN PRO-FIBROTIC MIRNA SIGNATURES AND COULD INDUCE MYOFIBROBLAST DIFFERENTIATION IN VITRO

Background:

Exosomes generated great resonance in the last few years due to their important roles in different biological pathways and diseases, including systemic sclerosis (SSc) (1). They are lipid-like nanovesicles containing biomarkers, such as proteins, lipids, macromolecules and nucleic acids, including microRNA (miRNA) (2). Exosomes are implicated in intercellular communication by fusing and releasing their cargo into the target cells (3).

Objectives:

In the present study, we evaluated the potential of exosomes deriving from plasma of SSc patients or generating from cultured SSc fibroblasts to drive the fibrotic signaling in the disease.

Methods:

Exosomes were isolated from plasma of n=10 SSc patients and from n=10 control subjects. Exosomes were also purified from cell culture supernatants of SSc fibroblasts and of control fibroblasts. Exosome size and concentration were assessed by Nanosight Particle Tracking Analysis (NTA) and by transmission electron microscopy (TEM). The content of anti-fibrotic (let-7a, 146a, 200a, 223a) and pro-fibrotic (150, 155) miRNAs was assessed in all the plasma-derived and cell culture-derived exosome populations by semiquantitative real time PCR. Finally, isolated exosomes were used to stimulate control dermal fibroblasts in culture. Gene expressions (COL1A1, ACTA2 and TAGLN) were assessed by quantitative real time PCR (qRT-PCR) and protein levels (type-I-collagen, α-SMA and SM22) by immunofluorescence (IF).

Results:

Exosomes isolated from SSc plasma samples showed higher concentration (3.3x1010±1.1x1010particles/mL) compared to those isolated from control plasma ones (1.5x1010±0.4x1010particles/mL) (p<0.01). The exosome size did not differ between SSc and control plasma samples and ranged from 50nm to 150nm. Similar results were obtained with exosomes generated from fibroblast cultures: the concentration was higher in SSc fibroblasts (1.1x1010±0.2x1010particles/mL) than in control ones (0.4x1010±0.1x1010particles/mL) (p<0.05) with no significant differences in size distribution. The content of all anti-fibrotic (let-7a, 146a, 200a, 223a) miRNAs was decreased in exosomes coming from both SSc plasma samples and from SSc fibroblasts with respect to control plasma samples (p<0.05) and to control fibroblasts (p<0.05). On the contrary, the pro-fibrotic (150, 155) miRNAs were significantly upregulated in exosomes deriving from SSc plasma samples and from SSc fibroblasts, with respect to control plasma samples (p<0.05) and to control fibroblasts (p<0.05). Finally, only exosomes coming from SSc plasma samples or SSc fibroblast cultures were able to induce pro-fibrotic gene (COL1A1, ACTA2 and TAGLN) and protein (type-I-collagen, α-SMA and SM22) expression in control fibroblasts. No pro-fibrotic induction was seen in presence of exosomes isolated from control plasma samples or control fibroblast cultures.

Conclusion:

This study demonstrates that plasma from SSc patients contains higher concentration of exosomes compared to plasma from control subjects and SSc-derived exosomes contain specific pro-fibrotic miRNA signatures that can induce myofibroblast differentiationin vitro. These results suggest that exosomes could be fibrotic drivers towards non-affected areasin vivo, and they might represent novel targets for precision medicine treatments in SSc.

References:

[1]Zhu T, Wang Y, Jin H, Li L. The role of exosome in autoimmune connective tissue disease. Ann Med. 2019 Mar;51(2):101-108.

[2]Wermuth PJ, Piera-Velazquez S, Rosenbloom J, et al. Existing and novel biomarkers for precision medicine in systemic sclerosis. Nat Rev Rheumatol. 2018 Jul;14(7):421-432.

[3]Colletti M, Galardi A, De Santis M, et al. Exosomes in Systemic Sclerosis: Messengers Between Immune, Vascular and Fibrotic Components? Int J Mol Sci. 2019 Sep 4;20(18). pii: E4337.

Disclosure of Interests:

Claudio Corallo: None declared, Maurizio Cutolo Grant/research support from: Bristol-Myers Squibb, Actelion, Celgene, Consultant of: Bristol-Myers Squibb, Speakers bureau: Sigma-Alpha, Stefano Soldano: None declared, Enrico Selvi: None declared, Francesca Bellisai: None declared, Nicola Giordano: None declared

Force on the lips of a trumpet player

When modeling a brass instrument such as the trumpet, an estimate of the pressure at the player's lips is essential, since the resulting force drives the oscillations of the lips which are needed to produce a musical tone. In most work to date, the calculation of the force on the lips has relied on values of the pressure derived from the Bernoulli equation, even though that relation assumes steady flow in contrast to the pulsating flow caused by vibrations of the lips. This paper uses a quantitative application of the Navier-Stokes equations to calculate the flow through a model of vibrating lips attached to a toy model of the trumpet. The results are used to explore when the Bernoulli equation can and cannot be used. The Bernoulli equation is found to fail badly during significant portions of each oscillation cycle of the lips. The reasons for this breakdown are elucidated.

Methylsulfonylmethane and mobilee prevent negative effect of IL-1β in human chondrocyte cultures via NF-κB signaling pathway

Nutraceuticals are compounds that serve as nutrition with an easy accessibility and favourable safety profile. Recent studies showed their potential activity on osteoarthritis (OA) inflammation and cartilage metabolism. We investigated the effect of methylsulfonylmethane (MSM) and mobilee in human OA chondrocyte cultures exposed to interleukin (IL)-1β. OA cartilage was obtained from femoral heads of five patients undergoing total replacement surgery. Chondrocytes were incubated with mobilee (200 and 500 μM) and MSM (2000 and 6000 μM) in presence of IL-1β (10 ng/mL) and nuclear factor (NF)-κB inhibitor (BAY 11-7082, 1 μM), for 24 and 48 h. Viability and apoptosis were performed by MMT and flow cytometry. The metalloproteinase (MMP)-1,-3,-13 and type II collagen (Col2a1) were analyzed by qRT-PCR and ELISA, and NF-κB activation by immunofluorescence. IL-1β stimulus determined a significant regulation of survival, apoptotic ratio, as well as of gene expression and serum levels of MMP-1,-3,-13 and Col2a1 in OA chondrocytes compared to baseline. Mobilee and MSM incubation significantly reversed the effect of IL-1β. IL-1β significantly induced NF-κB p50 nuclear translocation, which was significantly counteracted by the pre-treatment of OA chodrocytes with the tested compounds. BAY11-7082 significantly modulated MMPs and Col2a1 expression respectively to basal state. Co-treatment of IL-1β with mobilee, MSM and BAY11-7082 didn't cause changes of MMPs or Col2a1 beyond that caused by each single treatment. We demonstrated that MSM and mobilee have a beneficial effect on OA chondrocytes metabolism, probably due to the modulation of NF-κB pathway, providing a powerful rationale for the use of these substances in OA treatment.

Evaluation of Activity of Phospholipids in Blood Coagulation in Vitro

1. The effects of phospholipids, solubilized by different methods in different clotting tests are presented.

2. Complete fatty acid analysis of a phosphatidylserine fraction from beef brain is given.

3. Data relating electric charge of phospholipid particles to activity in clotting are presented.

4. A critical discussion of the factors which influence the activity of phospholipids in blood clotting terminates the paper.

D-dimer levels in VTE patients with distal and proximal clots

OBJECTIVES

There is growing evidence that venous thromboembolism (VTE) patients with distal clots (distal calf deep vein thrombosis [DVT] and sub-segmental pulmonary embolism [PE]) may not routinely benefit from anticoagulation. We compared the D-dimer levels in VTE patients with distal and proximal clots.

METHODS

We conducted a multinational, prospective observational study of low-to-intermediate risk adult patients presenting to the emergency department (ED) with suspected VTE. Patients were classified as distal (calf DVT or sub-segmental PE) or proximal (proximal DVT or non-sub-segmental PE) clot groups and compared with univariate and multivariate analyses.

RESULTS

Of 1752 patients with suspected DVT, 1561 (89.1%) had no DVT, 78 (4.4%) had a distal calf DVT, and 113 (6.4%) had a proximal DVT. DVT patients with proximal clots had higher D-dimer levels (3760 vs. 1670 mg/dL) than with distal clots. Sensitivity and negative predictive value (NPV) for proximal DVT at an optimal D-dimer cutoff of 5770 mg/dL were 40.7% and 52.1% respectively. Of 1834 patients with suspected PE, 1726 (94.1%) had no PE, 7 (0.4%) had isolated sub-segmental PE, and 101 (5.5%) had non-sub-segmental PE. PE patients with proximal clots had higher D-dimer levels (4170 vs. 2520 mg/dL) than those with distal clots. Sensitivity and NPV for proximal PE at an optimal D-dimer cutoff of 3499 mg/dL were 57.4% and 10.4% respectively.

CONCLUSIONS

VTE patients with proximal clots had higher D-dimer levels than patients with distal clots. However, D-dimer levels cannot be used alone to discriminate between VTE patients with distal or proximal clots.

Metabolomic analysis of 92 pulmonary embolism patients from a nested case-control study identifies metabolites associated with adverse clinical outcomes

Essentials Risk-stratification often fails to predict clinical deterioration in pulmonary embolism (PE). First-ever high-throughput metabolomics analysis of risk-stratified PE patients. Changes in circulating metabolites reflect a compromised energy metabolism in PE. Metabolites play a key role in the pathophysiology and risk stratification of PE.

SUMMARY

Background Patients with acute pulmonary embolism (PE) exhibit wide variation in clinical presentation and outcomes. Our understanding of the pathophysiologic mechanisms differentiating low-risk and high-risk PE is limited, so current risk-stratification efforts often fail to predict clinical deterioration and are insufficient to guide management. Objectives To improve our understanding of the physiology differentiating low-risk from high-risk PE, we conducted the first-ever high-throughput metabolomics analysis (843 named metabolites) comparing PE patients across risk strata within a nested case-control study. Patients/methods We enrolled 92 patients diagnosed with acute PE and collected plasma within 24 h of PE diagnosis. We used linear regression and pathway analysis to identify metabolites and pathways associated with PE risk-strata. Results When we compared 46 low-risk with 46 intermediate/high-risk PEs, 50 metabolites were significantly different after multiple testing correction. These metabolites were enriched in the following pathways: tricarboxylic acid (TCA) cycle, fatty acid metabolism (acyl carnitine) and purine metabolism, (hypo)xanthine/inosine containing. Additionally, energy, nucleotide and amino acid pathways were downregulated in intermediate/high-risk PE patients. When we compared 28 intermediate-risk with 18 high-risk PE patients, 41 metabolites differed at a nominal P-value level. These metabolites were enriched in fatty acid metabolism (acyl cholines), and hemoglobin and porphyrin metabolism. Conclusion Our results suggest that high-throughput metabolomics can provide insight into the pathophysiology of PE. Specifically, changes in circulating metabolites reflect compromised energy metabolism in intermediate/high-risk PE patients. These findings demonstrate the important role metabolites play in the pathophysiology of PE and highlight metabolomics as a potential tool for risk stratification of PE.

Physical modeling of a conical lip reed instrument

A model of a brass instrument is described in which the air flow and pressure inside the instrument are computed with the Navier-Stokes equations and the motion of the player's lips are described using the swinging lip model of Adachi and Sato [J. Acoust. Soc. Am. 99, 1200-1209 (1996)]. Using the Navier-Stokes equations to treat the air motion allows the calculation of the spatial variations and time dependences of the pressure and velocity near the lips, which has not been possible with previous modeling approaches. Detailed results for these quantities and for the lip motion are presented, and compared with the results of previous modeling of lip reed instruments and with available experimental results. Shortcomings are found in previous treatments of the aerodynamic force on the lips, and the implications of this result for first-principles modeling of brass instruments are discussed.

Can balneotherapy modify microRNA expression levels in osteoarthritis? A comparative study in patients with knee osteoarthritis

The aim of this study was to evaluate the whole-blood levels of miR-155, miR-223, miR-181a, miR-146a, and miR-let-7e in patients with bilateral knee osteoarthritis (OA) after a cycle of mud-bath therapy (MBT). Thirty-two patients with knee OA defined by the ACR criteria were included. Twenty-one patients (MBT group) were daily treated with a combination of local mud-packs at 42 °C and baths in mineral water, at 37 °C for 15 min, for 12 applications over a period of 2 weeks, in addition to standard therapy; 11 patients (control group) continued their conventional treatment alone. Global pain score evaluated by visual analog scale (VAS), WOMAC subscores, and microRNA expression were evaluated at baseline and after 2 weeks. Peripheral whole blood was collected into PAXgene™ Blood RNA tubes, stored at - 80 °C, and total RNA was extracted. The expression of miR-155, miR-223, miR-181a, miR-146a, and miR-let-7e was determined by qRT-PCR. After MBT, we observed a statistically significant improvement of clinical parameters and a significant decrease of miR-155, miR-181a, miR-146a (p < 0.001), and miR-223 (p < 0.01) expression levels. No clinical and biochemical modifications were detected in the control group. No significant variations of miR-let-7e were shown in both groups after 2 weeks. In conclusion, MBT can modify the expression of miR-155, miR-181a, miR-146a, and miR-223, which are upregulated in OA. It could be due to the heat stress and the hydrostatic pressure, since some miRNAs were found to be temperature- and mechano-responsive. Further studies are needed to better explain the mechanism of action of MBT and the role of miRNAs in OA.

From microvasculature to fibroblasts: Contribution of anti-endothelial cell antibodies in systemic sclerosis

Systemic sclerosis (SSc) is an autoimmune disease characterized by skin and internal organ fibrosis, caused by microvascular dysfunction. In recent years, the hypothesis that anti-endothelial cell antibodies (AECA) play a key role in microvascular damage seems to be increasingly convincing. In fact, AECA can induce antibody-dependent cellular apoptosis and stimulate the microvasculature to release pro-inflammatory and pro-fibrotic cytokines. Human-microvascular-endothelial-cells (MVECs) were stimulated with SSc sera (with and without AECA) and with sera from healthy donors. The conditioned MVEC culture media were then added to fibroblast cultures obtained from control skin (CTR), non-affected skin of SSc patients (NA), and affected skin of the same sclerodermic (SSc) patients, respectively. AECA contributed to the MVEC increased release of endothelin-1 (ET-1) in the culture medium and to MVEC apoptosis. Fibroblast (CTR, NA, and SSc) proliferation was increased after treatment with AECA-positive conditioned media, compared to AECA-negative and control conditioned media. Furthermore, both AECA-positive (in major contribution) and AECA-negative conditioned media were responsible for alpha-smooth-muscle-actin (αSMA) over-expression in all fibroblast cultures, compared to control conditioned media. Fibroblast type I collagen synthesis was upregulated by both SSc conditioned media (with and without AECA). Finally, the synthesis of fibroblast transforming-growth-factor-beta (TGF-β) was statistically higher in AECA-positive conditioned media, compared to AECA-negative and control conditioned media. These findings support the concept that AECA may mediate the crosstalk between endothelial damage and dermal-fibroblast activation in SSc.

Computational study of the piccolo: Evidence for chaotic tones

Direct numerical solutions of the Navier-Stokes equations have been used to compute tones produced by a model of the piccolo. The behavior depends on the angle at which the air jet is directed at the embouchure hole and the displacement of the jet center from the embouchure edge. Values of the jet angle and displacement are found that produce pure tones with spectra similar to those of real piccolo tones. The behavior of calculated tones as a function of the blowing speed u is studied, and it is found that unsteady behavior can occur depending on the value of u, the jet angle, and the jet displacement. Detailed analysis of these unsteady tones suggests that the model piccolo studied here exhibits chaotic behavior with a positive Lyapunov exponent. The implications for piccolo tones produced with real piccolos by real piccolo players are discussed.

The Effect of Reduction on the Adsorptive Behaviour of the TiO2/Water Interface

The effect of mild reduction treatment on TiO2 surfaces has been investigated by the ZPC (zero point of charge) potentiometric technique. Different extents of reduction result in a series of oxides distinguished either by their adsorption characteristics or electrochemical properties. Non-stoichiometric surface oxide formation has been demonstrated by X-ray diffraction and flat-band potential (Vfb) measurements. The generation of surface states with essentially acid–base characteristics has been shown to be a determining factor in the photo-oxidation–photodecomposition of water. A number of hypotheses relating to the nature of the adsorption-determining sites have been advanced.

Identification of High-Risk Plaques by MRI and Fluorescence Imaging in a Rabbit Model of Atherothrombosis

Introduction

The detection of atherosclerotic plaques at risk for disruption will be greatly enhanced by molecular probes that target vessel wall biomarkers. Here, we test if fluorescently-labeled Activatable Cell Penetrating Peptides (ACPPs) could differentiate stable plaques from vulnerable plaques that disrupt, forming a luminal thrombus. Additionally, we test the efficacy of a combined ACPP and MRI technique for identifying plaques at high risk of rupture.

Methods and Results

In an atherothrombotic rabbit model, disrupted plaques were identified with in vivo MRI and co-registered in the same rabbit aorta with the in vivo uptake of ACPPs, cleaved by matrix metalloproteinases (MMPs) or thrombin. ACPP uptake, mapped ex vivo in whole aortas, was higher in disrupted compared to non-disrupted plaques. Specifically, disrupted plaques demonstrated a 4.5~5.0 fold increase in fluorescence enhancement, while non-disrupted plaques showed only a 2.2~2.5 fold signal increase. Receiver operating characteristic (ROC) analysis indicates that both ACPPs (MMP and thrombin) show high specificity (84.2% and 83.2%) and sensitivity (80.0% and 85.7%) in detecting disrupted plaques. The detection power of ACPPs was improved when combined with the MRI derived measure, outward remodeling ratio.

Conclusions

Our targeted fluorescence ACPP probes distinguished disrupted plaques from stable plaques with high sensitivity and specificity. The combination of anatomic, MRI-derived predictors for disruption and ACPP uptake can further improve the power for identification of high-risk plaques and suggests future development of ACPPs with molecular MRI as a readout.

Explaining the Railsback stretch in terms of the inharmonicity of piano tones and sensory dissonance

The perceptual results of Plomp and Levelt [J. Acoust. Soc. Am. 38, 548-560 (1965)] for the sensory dissonance of a pair of pure tones are used to estimate the dissonance of pairs of piano tones. By using the spectra of tones measured for a real piano, the effect of the inharmonicity of the tones is included. This leads to a prediction for how the tuning of this piano should deviate from an ideal equal tempered scale so as to give the smallest sensory dissonance and hence give the most pleasing tuning. The results agree with the well known "Railsback stretch," the average tuning curve produced by skilled piano technicians. The authors' analysis thus gives a quantitative explanation of the magnitude of the Railsback stretch in terms of the human perception of dissonance.

Gender-specific associations of appendicular muscle mass with BMD in elderly Italian subjects

Currently used diagnostic measures for sarcopenia are based on the evaluation of appendicular skeletal muscle mass (ASMM) divided by height-squared (ASMMI). This study aimed to investigate the associations between different operational definitions of appendicular muscle mass and BMD at different skeletal sites in aging Italian men and women. In 1199 consecutive healthy Italian subjects, aged 55 years or more (854 women, age 64.2 ± 6.4 years and 165 men, age 65.3 ± 6.1 years), we measured BMD at the lumbar spine (LS-BMD), at femoral neck (FN-BMD),at total hip (TH-BMD), at total body (WB-BMD) and at the right hand (H-BMD) and body composition parameters [ASMM, ASMMI, ASMM/Weight, total lean mass and total fat mass by DXA]. In all subjects, we also measured sex hormones, 25-hydroxyvitamin D and bone turnover markers. In men, both ASMM and ASMMI were positively correlated with BMD at all sites, whereas in women, ASMM and ASMMI did not show any significant correlation with BMD. In men, multiple regression analyses showed that ASMM was positively associated (p < 0.01) with FN-BMD, TH-BMD and H-BMD; however, these associations were no longer present when lean mass was included. In women, both fat mass and lean mass were found positively associated with BMD at all sites. In conclusion, among the different operational measures of the ASMM, only ASMM was significantly associated with BMD in elderly men, but not in elderly women.

Is osteopontin involved in cutaneous fibroblast activation? Its hypothetical role in scleroderma pathogenesis

Osteopontin (OPN) is an extracellular matrix protein implicated in bone remodeling, but it presents also pro-inflammatory and pro-fibrotic properties. OPN expression also occurs upon exposure of cells to classical mediators of acute inflammation such as tumor necrosis growth factor alpha (TNF-alpha) and interleukin-1 beta (IL-1beta), as well as fibrogenic cytokines such as transforming growth factor beta (TGF-beta), although a detailed understanding of these regulatory pathways is still unknown. Plasma OPN levels in both limited and diffuse systemic sclerosis patients (lSSc and dSSc) were statistically higher compared to those of control subjects. Immunohistology demonstrated that high TGF-beta levels, alpha smooth muscle actin (alphaSMA) levels and consequently high OPN levels were found in the affected skin of sclerodermic patients (lSSc and dSSc) compared to levels found in healthy skin. In order to better understand how OPN interferes with the fibrotic process, healthy skin fibroblasts were treated for 24 and 48 hours with bleomycin and with endothelin-1 (ET-1) plus TGF-beta in order to induce the fibrogenesis. After 48 hours of stimulation, healthy treated fibroblasts showed statistically increased alphaSMA levels (index of differentiation into myofibroblasts) and simultaneously statistically increased OPN levels compared to healthy untreated ones. This study demonstrates that OPN levels increase simultaneously with the increasing of alphaSMA levels, therefore it is reasonable to hypothesize that OPN interferes in the pathogenesis of Systemic Sclerosis in the early stage of fibroblast differentiation process.

Simulation studies of a recorder in three dimensions

The aeroacoustics of a recorder are explored using a direct numerical simulation based on the Navier-Stokes equations in three dimensions. The qualitative behavior is studied using spatial maps of the air pressure and velocity to give a detailed picture of jet dynamics and vortex shedding near the labium. In certain cases, subtle but perhaps important differences in the motion of the air jet near the edge of the channel as compared to the channel center are observed. These differences may be important when analyzing experimental visualizations of jet motion. The quantitative behavior is studied through analysis of the spectrum of the sound pressure outside the instrument. The effect of chamfers and of changes in the position of the labium relative to the channel on the tonal properties are explored and found to be especially important in the attack portion of the tone. Changes in the spectrum as a result of variations in the blowing speed are also investigated as well as the behavior of the spectrum when the dominant spectral component switches from the fundamental to the second harmonic mode of the resonator tube.

Alpha lipoic acid and superoxide dismutase in the treatment of chronic low back pain

BACKGROUND

Neuropathic mechanisms largely contribute to low back pain (LBP) and oxidative stress is acknowledged as one of the causes of nerve damage typical of neuropathic pain: antioxidant agents may be a useful choice in the multimodal treatment strategy for chronic LBP patients.

AIM

The aim of this study was to detect changes in perceived pain, functional activity and in the assumption of analgesics in patients with chronic LBP treated with a combination of alpha-lipoic acid (ALA) and superoxide dismutase (SOD).

DESIGN

Prospective non-randomized open-label study.

SETTING

Outpatient at TAMMEF (Therapeutic Application of Musically Modulated Electromagnetic Fields) Centre of the University of Siena.

POPULATION

The study enrolled 98 adult patients with chronic (≥12 weeks) LBP with or without radiculopathy and without neoplastic or inflammatory pathologies.

METHODS

Patients were treated for 60 days with 600 mg ALA and 140 UI SOD/die. The Roland Morris Disability Questionnaire and Pain Rating Scale were used and concomitant use of medications (with particular attention to analgesics) and adverse events (toxicity) were recorded during treatment. Differences between all the study time points were calculated for the scores of the two tools and for the need of concomitant treatment with analgesics.

RESULTS

At the end of the study only 8% of patients still used analgesics versus 73.5% registered at baseline (P<0.01). Regarding self-reported tools, a statistically significant improvement both for perceived pain and functional disabilities occurred: pain ameliorated after 40 days of therapy and the improvement was significant both statistically (P<0.05) and clinically. Only 4 patients stopped the treatment due to unacceptable pain (not related to the treatment).

CONCLUSION

Oral treatment with ALA and SOD improves functionality and reduces the use of analgesics in chronic LBP patients.

CLINICAL REHABILITATION IMPACT

Oral combination of ALA and SOD may be a powerful adjuvant in multimodal therapy of chronic LBP patients.

Collagen-gelatin-genipin-hydroxyapatite composite scaffolds colonized by human primary osteoblasts are suitable for bone tissue engineering applications: in vitro evidences

The application of porous hydroxyapatite (HAp)-collagen as a bone tissue engineering scaffold represents a new trend of mimicking the specific bone extracellular matrix (ECM). The use of HAp in reconstructive surgery has shown that it is slowly invaded by host tissue. Therefore, implant compatibility may be augmented by seeding cells before implantation. Human primary osteoblasts were seeded onto innovative collagen-gelatin-genipin (GP)-HAp scaffolds containing respectively 10%, 20%, and 30% HAp. Cellular adhesion, proliferation, alkaline phosphatase (ALP) activity, osteopontin (OPN), and osteocalcin (OC) expressions were evaluated after 3, 7, 15, and 21 days. The three types of scaffolds showed increased cellular proliferation over time in culture (maximum at 21 days) but the highest was recorded in 10% HAp scaffolds. ALP activity was the highest in 10% HAp scaffolds in all the times of evaluation. OC and OPN resulted in higher concentration in 10% HAp scaffolds compared to 20% and 30% HAp (maximum at 21 days). Finally, scanning electron microscopy analysis showed progressive scaffolds adhesion and colonization from the surface to the inside from day 3 to day 21. In vitro attachment, proliferation, and colonization of human primary osteoblasts on collagen-GP-HAp scaffolds with different percentages of HAp (10%, 20%, and 30%) all increased over time in culture, but comparing different percentages of HAp, they seem to increase with decreasing of HAp component. Therefore, the mechanical properties (such as the stiffness due to the HAp%) coupled with a good biomimetic component (collagen) are the parameters to set up in composite scaffolds design for bone tissue engineering.

Macitentan slows down the dermal fibrotic process in systemic sclerosis: in vitro findings

Systemic sclerosis (or scleroderma) is an autoimmune disease characterized by skin and internal organ fibrosis, caused by microvascular dysfunction. The microvascular damage seems to be a consequence of an endothelial autoimmune response, followed by activation of the inflammatory cascade and massive deposition of collagen. Endothelin-1 (ET-1) contributes to the inflammatory and fibrotic processes by increasing the concentration of pro-inflammatory and pro-fibrotic cytokines, and it is considered one of the most relevant mediators of vascular damage in scleroderma. It is indeed found in very high concentration in serum of sclerodermic patients. Moreover, in these pathological conditions there is an increased expression of ET-1 receptors (ETA and ETB), which mediate the detrimental action of ET-1, and often a change of ETA/ETB ratio. The aim of the present study is to evaluate the in vitro effect of macitentan, an orally active tissue-targeting dual endothelin receptor antagonist, and its major metabolite (ACT-132577) on alpha smooth muscle actin (alphaSMA) expression, evaluated on dermal fibroblasts from healthy subjects and on dermal fibroblasts from lesional and non-lesional skin from sclerodermic patients. The combination of macitentan and its major metabolite reduced the levels of &#945;SMA after 48 h in sclerodermic fibroblasts from lesional skin. No relevant changes in &#945;SMA levels were found in fibroblasts from non-lesional skin, whose behavior is similar to that of dermal fibroblasts from healthy patients.

Direct numerical simulation of a recorder

The aeroacoustics of a recorder are studied using a direct numerical simulation based on the Navier-Stokes equations in two dimensions. Spatial maps for the air pressure and velocity give a detailed picture of vortex shedding near the labium. Changes in the spectrum as a result of variations in the blowing speed are also investigated. The results are in good semi-quantitative agreement with general results for these phenomena from experiments.

Therapeutic Application of Musically Modulated Electromagnetic Fields in the Treatment of Musculoskeletal Disorders

Different studies have demonstrated the efficacy of extremely low frequency electromagnetic fields (ELF EMFs) in the treatment of pain. In particular, the positive effects of ELF EMFs seems to depend on their respective codes, such as frequency, intensity and waveform, even if the exact mechanism of interaction is still debated. The most commonly used for extremely low frequency magnetotherapy is a 100Hz sinusoidal field (ELF) with a mean of induction of few Gauss. This article reviews the therapeutic application of a musically modulated electromagnetic field (TAMMEF), a new-generation of electromagnetic field used for extremely low frequency magnetotherapy characterized by variable frequencies, intensities and waveforms. Both clinical and experimental studies, performed by authors of the present review, have demonstrated the efficacy of ELF and the new TAMMEF systems in several musculoskeletal disorders such as osteoarthritis, rheumatoid arthritis, carpal tunnel syndrome, shoulder periarthritis and cervical spondylosis. Moreover, it has been demonstrated that ELF and TAMMEF systems are not only effective, but also safe, from clinical and experimental point of view. In fact, clinical trials did not reported any undesired side effect, while in vitro studies showed that ELF EMFs did not induce uncontrolled cell proliferation, did not affect cell viability and did not induce apoptosis. With their efficacy and safety, ELF and even more the new TAMMEF systems represent a valid complementary or alternative treatment to standard pharmacological therapies in reducing both pain and inflammation of patients affected by musculoskeletal disorders.

Detection of thrombus size and protein content by ex vivo magnetization transfer and diffusion weighted MRI

BACKGROUND

To utilize a rabbit model of plaque disruption to assess the accuracy of different magnetic resonance sequences [T1-weighted (T1W), T2-weighted (T2W), magnetization transfer (MT) and diffusion weighting (DW)] at 11.7 T for the ex vivo detection of size and composition of thrombus associated with disrupted plaques.

METHODS

Atherosclerosis was induced in the aorta of male New Zealand White rabbits (n = 17) by endothelial denudation and high-cholesterol diet. Subsequently, plaque disruption was induced by pharmacological triggering. Segments of infra-renal aorta were excised fixed in formalin and examined by ex vivo magnetic resonance imaging (MRI) at 11.7 T and histology.

RESULTS

MRI at 11.7 T showed that: (i) magnetization transfer contrast (MTC) and diffusion weighted images (DWI) detected thrombus with higher sensitivity compared to T1W and T2W images [sensitivity: MTC = 88.2%, DWI = 76.5%, T1W = 66.6% and T2W = 43.7%, P < 0.001]. Similarly, the contrast-to-noise (CNR) between the thrombus and the underlying plaque was superior on the MTC and DWI images [CNR: MTC = 8.5 ± 1.1, DWI = 6.0 ± 0.8, T1W = 1.8 ± 0.5, T2W = 3.0 ± 1.0, P < 0.001]; (ii) MTC and DWI provided a more accurate detection of thrombus area with histology as the gold-standard [underestimation of 6% (MTC) and 17.6% (DWI) compared to an overestimation of thrombus area of 53.7% and 46.4% on T1W and T2W images, respectively]; (iii) the percent magnetization transfer rate (MTR) correlated with the fibrin (r = 0.73, P = 0.003) and collagen (r = 0.9, P = 0.004) content of the thrombus.

CONCLUSIONS

The conspicuity of the thrombus was increased on MTC and DW compared to T1W and T2W images. Changes in the %MTR and apparent diffusion coefficient can be used to identify the organization stage of the thrombus.

Abstract 348: Serial MRI Differentiates the Natural History of Stable and Vulnerable Plaques in a Rabbit Aorta

Non-invasive monitoring of human atherosclerotic plaque progression would be extremely valuable for determining the characteristics of vulnerable plaques before they rupture and for evaluating therapeutic interventions. We have shown that MRI is a reliable method for differentiating stable and vulnerable aortic atherosclerotic plaques in a rabbit model of atherothrombosis. In this study, we imaged rabbits at 4 time points (baseline, 1, 2 and 3 months) to monitor the progression of plaques and investigate when stable and vulnerable plaques can be differentiated. MR images and histology of two plaques in the same rabbit aorta are compared below. The top row of black blood (BB) T1 images (with fat suppression) show no significant changes in the lumen or the vessel wall area, and no thrombus in the stable plaque after triggering to induce plaque rupture. The histology showed an intact fibrous cap, overlying diffuse lipids. In comparison, there is a marked increase in vessel wall area in the vulnerable plaque (from 4.1 to 15 mm2 over 3 months). The second row (T1BB FS with Gd) shows some uptake of Gd into the stable plaque and surrounding tissue, but the vulnerable plaque showed rapidly increased Gd uptake between months 2 and 3. The vulnerable plaque also showed a large luminal thrombus in the MR images of the live rabbit and in the corresponding histology slice. In addition, the vulnerable plaque showed excessive outward remodeling at 2 months (data not shown). Our study shows a progression of vulnerable features, clearly evident at 2 months, in the plaque that disrupted. We are currently investigating whether therapies initiated at 2 months will reduce the progression of plaque vulnerability.

The C825T GNB3 polymorphism, independent of blood pressure, predicts cerebrovascular risk at a population level

BACKGROUND

The role of C825T polymorphism of the candidate GNB3 gene in predicting cerebrovascular outcome has been poorly explored in longitudinal setting at a population level.

METHODS

In an epidemiological setting, 1,678 men and women from general population were genotyped for C825T polymorphism of GNB3 gene and follow-up for 10 years to detect nonfatal and fatal cerebrovascular events (CE). Established cerebrovascular risk factors were used to adjust the multivariate Cox analysis for confounders.

RESULTS

Seventy-three nonfatal and 30 fatal CE were recorded. Incidence of CE was higher in TT than in C-carriers (fatal: 2.6 vs. 1.7%, P < 0.03; nonfatal: 7.8 vs. 3.9%, P < 0.03; fatal recurrences: 1.6 vs. 0.6%, P < 0.03). In Cox analysis, the TT genotype predicted nonfatal (hazard ratio 1.99, 95% confidence interval 1.05-3.79, P = 0.03), fatal (2.91, 1.05-8.12, P = 0.04), and fatal recurrent CE (6.82, 1.50-31.1, P = 0.02) also after adjustment for age, gender, systolic and diastolic blood pressure, body adiposity, atherogenetic blood lipids, serum uric acid, diabetes, calories, caffeine and ethanol intake, and coronary events at baseline. Further adjustment for historical CE made the association between TT genotype and incident fatal CE nonsignificant (hazard ratio 2.72, 95% confidence interval 0.96-7.22, P = 0.06).

CONCLUSIONS

The TT genotype of GNB3 gene predicts incident CE independent of blood pressure and other established risk factors at a population level. Further studies are needed to clarify the nature and pathways of this association.

In vitro exposure of human osteoarthritic chondrocytes to ELF fields and new therapeutic application of musically modulated electromagnetic fields: biological evidence

Osteoarthritis (OA) is the most frequently occurring rheumatic disease, caused by metabolic changes in chondrocytes, the cells that maintain cartilage. Treatment with electromagnetic fields (MF) produces benefits in patients affected by this pathology. Isolated human osteoarthritic (OA) chondrocytes were cultured in vitro under standard conditions or stimulated with IL-1beta or IGF-1, to mimic the imbalance between chondroformation and chondroresorption processes observed in OA cartilage in vivo. The cells were exposed for a specific time to extremely low frequency (ELF; 100-Hz) electromagnetic fields and to the Therapeutic Application of Musically Modulated Electromagnetic Fields (TAMMEF), which are characterized by variable frequencies, intensities, and waveforms. Using flow cytometry, we tested the effects of the different types of exposure on chondrocyte metabolism. The exposure of the cells to both systems enhances cell proliferation, does not generate reactive oxygen species, does not cause glutathione depletion or changes in mitochondrial transmembrane potential and does not induce apoptosis. This study presents scientific support to the fact that MF could influence OA chondrocytes from different points of view (viability, ROS production and apoptosis). We can conclude that both ELF and TAMMEF systems could be recommended for OA therapy and represent a valid non-pharmacological approach to the treatment of this pathology.

Cytokine modulation by endothelin-1 and possible therapeutic implications in systemic sclerosis

Systemic sclerosis (SSc), also known as scleroderma, is an autoimmune disorder characterized by a progressive fibrosis which involves skin and internal organs, caused by microvascular damage. The earliest clinical sign of the disease is Raynauds Phenomenon, a vasospastic response to cold or stress stimuli, followed by the skin and organ involvement over time. This kind of vascular manifestation originates from the microvascular structural alteration, characterized by an abnormal myocyte cell proliferation, intima cell proliferation and adventitia fibrosis. The microvascular damage seems to be the consequence of the autoimmune attack to the endothelium, followed by inflammatory cascade and massive deposition of collagen. From the beginning of the disorder, serum Endothelin-1 (ET- 1) is found in very high concentration: this protein, today, is considered one of the most important mediators of scleroderma vascular alterations. Furthermore, many recent studies have shown that ET-1 is involved in the inflammatory and fibrotic processes, increasing the concentration of pro-fibrotic and pro-inflammatory cytokines. The aim of this review is to clarify the ET-1 role in SSc, in particular the relationship between ET-1 and cytokine expression, adding another element to the understanding of scleroderma disease.

Bosentan treatment for Raynauds phenomenon and skin fibrosis in patients with Systemic Sclerosis and pulmonary arterial hypertension: an open-label, observational, retrospective study

Raynaud?s phenomenon (RP) and cutaneous fibrosis are the distinctive manifestations of scleroderma, in which Endothelin-1 plays a fundamental pathogenetic role. Bosentan, an Endothelin-1 receptor antagonist used for the treatment of pulmonary arterial hypertension, retards the beginning of new sclerodermic digital ulcers (DU). This open-label, observational, retrospective study verified the effect of Bosentan on RP and skin fibrosis in sclerodermic outpatients affected by pulmonary arterial hypertension without DU. Fourteen subjects (13 women, 1 man; mean age 60 ± 7.5 years; ten with limited and four with diffuse scleroderma) were observed at baseline (T0) and after four (T1), twelve (T2), twenty-four (T3) and forty-eight (T4) weeks during treatment with Bosentan. They were evaluated for daily quantity and duration of RP attacks and skin thickness (using modified Rodnan total skin score, MRSS). Videocapillaroscopic evaluation was performed at T0 and T4. Bosentan decreased significantly the number and duration of RP attacks, beginning at T2 (p<0.05). Videocapillaroscopy showed significant improvement of microcirculatory patterns at T4 (p<0.05). MRSS decreased throughout the study, reaching the statistical significance at T3 and T4 (p<0.01) in the whole cohort. The present data suggest that Bosentan is effective in stabilizing the microcirculation involvement and in improving skin fibrosis irrespective of scleroderma patterns.

Serum Proteome of Patients with Systemic Sclerosis: Molecular Analysis of Expression and Prevalence of Haptoglobin Alpha Chain Isoforms

Haptoglobin (Hpt) is an acute phase protein characterized by three major phenotypes (Hpt 1-1, Hpt 2-1 and Hpt 2-2). The Hpt 2-2 phenotype is associated with increased prevalence of various systemic diseases, including autoimmune disorders. Moreover, the Hpt 2-2 phenotype induces a shift from Th1 to Th2 response and increases fibrotic processes. On this basis, we performed serum proteomic analysis of with Systemic Sclerosis (SSc), a connective tissue disorder associated with Th2-type immune response and characterized by interstitial and perivascular fibrosis due to different factors (including genetic, environmental, immunological and microchimeric factors). Serum of 23 SSc outpatients (4 males, 19 females, mean age 54±5.3 years) diagnosed according to the American Rheumatism Association (ARA) criteria, were considered for the proteomic analysis and compared to serum of 21 control subjects. Serum depleted of HAP was analyzed by 2-DE, and Hpt chain spots were identified by WB. The expression frequency of each Hpt a chain in SSc patients and controls was compared and quantitative analysis of spot expression (% Vol) was performed. Above all, our study amplifies the limited data in the literature on proteomic analysis in SSc, also confirming previous data that revealed a significant increase of haptoglobin type 2-2 and a concomitant decrease of the 1-1 phenotype in SSc patients. Moreover, our results demonstrate that c spots are more prevalent in SSc patients than in controls (91.3% vs 55.5%, p<0.05), while the expression frequency of a and b spots does not change. In patients Hpt 2-1 or Hpt 1-1 e spot is less abundant. According to our results, the c and e spots can be considered markers for SSc and thus be of use for the early diagnosis of connective tissue disorders and in establishing appropriate treatment.

Magnetic resonance imaging in Tietze's syndrome

OBJECTIVE

To evaluate the usefulness of magnetic resonance imaging (MRI) in Tietze's syndrome which, to our knowledge, has not previously been reported in the literature.

METHODS

Twelve consecutive outpatients with clinical features of Tietze's syndrome underwent evaluation, including the anamnesis, clinical general examination, clinical evaluation of costosternal and sternoclavicular joints (SCJ) and biochemical and instrumental investigations. Twenty normal subjects age- and sex-matched to the patients' group were examined in a similar manner. MRI of costosternal and SCJ was performed using a 1.5 Tesla unit (Gyroscan NT 1.5 Philips, The Netherlands and GE Signa Excite HD, GE Healthcare, Milwaukee, Wis., USA).

RESULTS

The MRI pattern of primary Tietze's syndrome was characterized as follows: enlargement and thickening of cartilage at the site of complaint (12/12 patients); focal or widespread increased signal intensities of affected cartilage on both TSE T2-weighted and STIR or FAT SAT images (10/12 patients); bone marrow oedema in the subcondral bone (5/12 patients); vivid gadolinium uptake in the areas of thickened cartilage, in the subcondral bone marrow and/or in capsule and ligaments (10/12, 4/12 and 7/12 patients respectively).

CONCLUSION

Magnetic resonance is an excellent technique to evidence both the cartilage and bone abnormalities, therefore it represents the elective method in the investigation of primary Tietze's syndrome, due to its high sensitivity, diagnostic reliability and biological advantages thanks to the lack of ionizing radiation.