A reduced-order-model-based equivalent circuit for piezoelectric micro-electro-mechanical-system loudspeakers modeling.

Piezoelectric micro-electro-mechanical-system (MEMS) speakers are emerging as promising implementations of loudspeakers at the microscale, as they are able to meet the ever-increasing requirements for modern audio devices to become smaller, lighter, and integrable into digital systems. In this work, we propose a finite element model (FEM)-assisted lumped-parameters equivalent circuit for a fast and accurate modeling of these types of devices. The electro-mechanical parameters are derived from a pre-stressed FEM eigenfrequency analysis, to account for arbitrarily complex geometries and for the shift of the speaker resonance frequency due to an initial non-null pre-deflected configuration. The parameters of the acoustical circuit are instead computed through analytical formulas. The acoustic short-circuit between the speaker front and rear sides is taken into account through a proper air-gaps modeling. The very good matching in terms of radiated sound pressure level among the equivalent circuit predictions, FEM simulations, and experimental data proves the ability of the proposed method to accurately simulate the speaker performance. Moreover, due to its generality, it represents a versatile tool for designing piezoelectric MEMS speakers.

Predictive factors for lymph node involvement in sporadic medullary thyroid microcarcinoma: a systematic review.

OBJECTIVE: The aim of the study was to determine the impact of laboratory and imaging tests in predicting central and lateral neck lymph node/LN involvement and in decision making for surgical extent. MATERIALS AND METHODS: A PubMed, Web of Science and Scopus search was performed according to PRISMA criteria. The relationship between nodule size, diagnostic biomarkers and imaging with LN involvement were evaluated. RESULTS: The available data analysis did not yield clear indications of the relationship between each of these topics and the presence, number, and location of LN involved. There was no conclusive data for the selective indication of central neck dissection in the preoperative diagnosis of microMTC. CONCLUSIONS: There is no justification for less invasive interventions than total thyroidectomy with lymph node dissection.

Urinary tract infections after early removal of urinary catheter in total joint arthroplasty.

OBJECTIVE: Postoperative urine retention (POUR) is a well-known complication after total joint arthroplasty (TJA). POUR is most commonly managed with an indwelling catheter. However, indwelling catheters have been associated with a substantial risk of urinary tract infection (UTI). The purpose of this study was to (1) evaluate the incidence of UTI and POUR in patient with indwelling urinary catheter after TJA, (2) identify the microorganisms responsible for catheter colonization, and (3) assess preoperative risk factors (gender, body mass index, hypertension, diabetes mellitus, smoking) associated with catheter colonization. PATIENTS AND METHODS: Patients undergoing primary TJA with no preoperative bacteriuria were enrolled. Prior to the draping of the surgical site, each patient received an indwelling catheter that was inserted under sterile conditions and remained in place for 24 hours. Urine and tip catheter cultures were performed after catheter removal. RESULTS: 55 patients (38 females and 17 males) were recruited (26 total knee and 29 total hip arthroplasties). POUR was not reported in any patient, and only 1 patient (1.8%) had UTI. Cultures of catheter tips were positive in 16 patients (29.1%). Only 1 of these patients had a positive urine culture. Enterococcus faecalis was the most common pathogen isolated. None of the preoperative variables was associated with the risk of catheter colonization. CONCLUSIONS: Data from this study support early catheter removal after TJA. Predominant catheter-isolated bacteria are enteric species. The culture of a catheter tip specimen should be discouraged for the diagnosis of UTI within the firsts 24 hours after surgery.

C3f is a potential tool for the staging of osteoarthritis.

An attractive method for osteoarthritis (OA) staging is the measurement of biochemical markers in biological fluids, which could reflect dynamic and quantitative changes in joint remodeling and therefore disease progression. Proteome analysis has been recognized as one of the most effective tools to explore biomarkers as it can furnish a wealth of information in both diagnosis and prognosis of diseases. We have recently described an innovative tool for peptidome and lipidome profiling of fluids based on mesoporous aluminosilicate (MPAS) and Matrix-Assisted Laser Desorption/Ionization time-of-flight Mass Spectrometry (MALDI-TOF MS). The aim of this study was to analyze peptide profiles of human synovial fluid in patients with different grade of OA using MALDI-TOF-MS technique in order to identify potential markers of disease progression. Twenty-five patients older than 50 years and affected by primary knee OA diagnosed according to clinical and radiological criteria were enrolled. For each patient a synovial fluid sample was aspirated from the affected knee and analyzed using MALDI-TOF-MS technique. A statistically significant difference in the normalized area of two peaks (m/z=1865 and m/z=2021) was detected among different stages of OA. The 2 peaks were identified as Complement C3 peptide fragments: C3f and C3f Des-Arg. The expression levels of these two peptides (m/z=1865 and 2021) decreased with the progression of OA degrees severity (ρs=-0.434, p=0.03, and ρs=-0.532, p=0.006, respectively). This marker may be a useful tool for assessing the severity of knee OA and it may be a novel target for drug discovery, specifically for the development of disease modifying OA drugs. However further studies are required to clarify the role of C3f in OA pathogenesis.

The effects of nonsteroidal anti-inflammatory drugs on clinical outcomes, synovial fluid cytokine concentration and signal transduction pathways in knee osteoarthritis. A randomized open label trial.

OBJECTIVE: We investigated the effects of celecoxib, diclofenac, and ibuprofen on the disease-specific quality of life, synovial fluid cytokines and signal transduction pathways in symptomatic knee osteoarthritis (OA). DESIGN: Ninety patients scheduled for a total knee arthroplasty (TKA) were randomized to six groups that were treated with low and high dosages of celecoxib, diclofenac or ibuprofen. At the time of the first admission (T0) and at surgery (T1 = 14 days after beginning of the nonsteroidal anti-inflammatory drugs (NSAIDs)), samples of knee synovial fluid were obtained from each patient for analysis. During the surgery the synovial tissue was harvested from the knee of patients. The Western Ontario and McMaster universities (WOMAC) score was used to evaluate the patient disease-specific quality of life at T0 and T1. Microarray tests performed at T0 and T1 were used to evaluate the effects of NSAIDs on Tumor necrosis factor (TNF)-alpha, Interleukin-6 (IL-6), IL8 and Vascular endothelial growth factor (VEGF) concentration in the synovial fluid. Western blot assays evaluated the effects of NSAIDs on MAP kinase (MAPK) signal transduction pathway in the synovial membrane. RESULTS: NSAID treatment induced a statistically significant improvement in the WOMAC score and a statistically significant decrease in the IL-6, VEGF and TNF-alpha concentration in the synovial fluid. Higher dosages of NSAIDs provided a greater improvement in the disease-specific quality of life of patients and lower concentrations of pro-inflammatory cytokines in the synovial fluid. Inhibition of MAPKs was noted after NSAID treatment. CONCLUSION: Short-term NSAID treatment improves the patient disease-specific quality of life with a parallel decrease in pro-inflammatory synovial fluid cytokine levels in knee OA. Signal transduction pathways may be involved in regulating the anti-inflammatory effects of NSAIDs. ClinicalTrial.gov: NCT01860833.

Characteristics and clinical implications of the pharmacokinetic profile of ibuprofen in patients with knee osteoarthritis.

BACKGROUND AND OBJECTIVE: Ibuprofen is a non-selective cyclo-oxygenase (COX)-1/COX-2 inhibitor used to treat pain conditions and inflammation. Limited data have been published concerning the pharmacokinetic profile and clinical effects of ibuprofen in patients with osteoarthritis (OA). In this paper we compared the pharmacokinetic and clinical profile of ibuprofen (at a dosage of from 800 mg/day to 1800 mg/day) administered in patients affected by severe knee OA. METHODS: Ibuprofen was administered for 7 days to patients who were scheduled to undergo knee arthroplasty due to OA. After 7 days, the ibuprofen concentration in plasma and synovial fluid was measured through both high-performance liquid chromatography (HPLC)-UV and gas chromatography-mass spectroscopy (GC/MS), while clinical effects were evaluated through both visual analogue scale (VAS) and Western Ontario and McMaster Universities (WOMAC) scores. The Naranjo scale and the WHO causality assessment scale were used for estimating the probability of adverse drug reactions (ADRs). The severity of ADRs was assessed by the modified Hartwig and Siegel scale. RESULTS: Ibuprofen showed a dose-dependent diffusion in both plasma and synovial fluid, which was related to the reduction of pain intensity and improvement of health status, without the development of ADRs. CONCLUSION: Ibuprofen at higher dosages can be expected to provide better control of OA symptoms as a result of higher tissue distribution.

Finite element modelling of a rotating piezoelectric ultrasonic motor.

The evaluation of the performance of ultrasonic motors as a function of input parameters such as the driving frequency, voltage input and pre-load on the rotor is of key importance to their development and is here addressed by means of a finite element three-dimensional model. First the stator is simulated as a fully deformable elastic body and the travelling wave dynamics is accurately reproduced; secondly the interaction through contact between the stator and the rotor is accounted for by assuming that the rotor behaves as a rigid surface. Numerical results for the whole motor are finally compared to available experimental data.

Expression of SLAM as a functional and phenotypic marker in women with recurrent miscarriage.

In the present work, we investigated the Th1 and Th2 cytokine patterns secreted by infiltrating endometrial lymphocytes from fertile women and from patients with recurrent spontaneous miscarriage (RSM). Moreover, we also analyzed the expression of cytokines in the whole endometrium from fertile and RSM women. Furthermore, we investigated the expression of the activation marker signaling lymphocytic activation molecule (SLAM) a cell surface glycoprotein expressed on lymphocytes that upon engagement boosts IFN-gamma production. Our results showed a slight increase in IL-10 expression in the endometrium of some fertile women, although no significant differences were found in IFN-gamma and IL-5 expression. In contrast, analysis of IFN-gamma production by polyclonal activated lymphocytes from endometrium and/or peripheral blood from fertile women showed a significant increase compared to RSM. Analysis of SLAM protein expression in luteal phase endometrial samples showed a significant increase in the levels of the receptor in RSM women compared to fertile women. These results correlated with a significant augmentation of SLAM levels in peripheral blood T-lymphocytes from RSM patients. Interestingly, after treatment of RSM patients with paternal mononuclear cells, surface-SLAM-expression in T-cells from RSM patients significantly decreased up to levels comparable to those of fertile women. Taken together, our results suggest that endometrial cells have not a defined pattern-cytokine-production under pre-implatatory conditions, and SLAM might be a potential marker for the diagnosis of RSM and an indicator useful to follow up the patient response to allogeneic immunotherapy.

Intracellular expression of CD69 in endometrial and peripheral T cells represents a useful marker in women with recurrent miscarriage: modulation after allogeneic leukocyte immunotherapy.

PROBLEM: To characterize in fertile women and women with recurrent spontaneous abortions (RSA) the expression and functional status of T cells expressing the CD69 molecule. METHOD OF STUDY: We analyzed by flow cytometry in peripheral blood and endometrium from fertile and RSA women, the surface and cytoplasmic expression of CD69 on gated T cells. In addition, we investigated by three-color flow cytometry the expression of cytokines, and subsets of memory T cells. RESULTS: In T cells, CD69 was restricted to the intracellular compartment with a higher frequency in RSA than in fertile women (68.2 +/- 12% versus 23.7 +/- 22%, P < 0.001, and 20 +/- 9.5% versus 2.1 +/- 3.8%, P < 0.005, in endometrium and peripheral blood, respectively). In contrast, the number of interferon-gamma+ (IFN-gamma+) secreting cells was higher (16 +/- 5% versus 6 +/- 1%) in fertile women. All 11 RSA women alloimmunized with parental leukocytes reached values of CD3 +/- CD69+ cells similar to those observed in fertile women. CONCLUSIONS: CD69 might represent a useful marker in the diagnosis and the follow up of RSA patients.

Induction of allogenic T-cell hyporesponsiveness by galectin-1-mediated apoptotic and non-apoptotic mechanisms.

Galectin-1, a beta-galactoside-binding protein expressed at sites of T-cell activation and immune privilege, has shown specific immunosuppressive properties. Because of the implications of this protein in T-cell tolerance and its potential use to avoid graft rejection, we investigated the immunosuppressive effects of galectin-1 in the course of the human allogenic T-cell response. Galectin-1 induced a dose- and carbohydrate-dependent inhibition of the allogenic T-cell response. Addition of galectin-1 to alloreactive lymphocytes resulted in significant apoptosis of CD45R0-positive cells. This negative regulatory effect was accompanied by caspase activation, Bcl-2 downregulation and was prevented by addition of exogenous IL-2. In addition, a significant decrease of IFN-gamma production was detected in the non-apoptotic cell population, following exposure of alloreactive lymphocytes to galectin-1. Moreover, the immunosuppressive activity of this protein did not involve TGF-beta-mediated mechanisms. Since galectin-1 is expressed by activated T cells and could be acting by an autocrine negative loop to control human T-cell reactivity, we finally examined the regulated expression of this protein throughout the allogenic T-cell response. Expression of endogenous galectin-1 was detected at 24 h of cell culture, reaching its maximal levels after 72 h of allostimulation. The present study sets the basis for a potential use of galectin-1 as a selective immunosuppressive agent to limit T-cell-mediated reactivity during the effector phase of the alloimmune response.

Indications for early surgery in cases of lumbar and dorsolumbar scoliosis: the role of vertebral rotation.

There are very few objective criteria for the choice between conservative and surgical treatment of lumbar and dorsolumbar scoliosis ranging from 40 to 50 degrees. We reviewed the long-term results obtained in 76 patients treated with plaster braces because they had refused surgical treatment; in 56% of the cases a nearly 10 degree gain was maintained after the onset of treatment; all of the cases which showed improvement presented a reduction in the curve by at least half and rotation by at least one-third in tests in suspension or in bending, and this was maintained in plaster. In cases where the long-term results were poor, however, rotation did not change. In conclusion, of the many parameters examined, only a combined assessment of the reducibility of both the Cobb angle and of rotation provides a valid indication for the treatment of lumbar and dorsolumbar curves ranging from 40 to 50 degrees.