Involvement of transcribed lncRNA uc.291 and SWI/SNF complex in cutaneous squamous cell carcinoma

While non-melanoma skin cancers (NMSCs) are the most common tumours in humans, only the sub-type cutaneous squamous cell carcinoma (cSCC), might become metastatic with high lethality. We have recently identified a regulatory pathway involving the lncRNA transcript uc.291 in controlling the expression of epidermal differentiation complex genes via the interaction with ACTL6A, a component of the chromatin remodelling complex SWI/SNF. Since transcribed ultra-conserved regions (T-UCRs) are expressed in normal tissues and are deregulated in tumorigenesis, here we hypothesize a potential role for dysregulation of this axis in cSCC, accounting for the de-differentiation process observed in aggressive poorly differentiated cutaneous carcinomas. We therefore analysed their expression patterns in human tumour biopsies at mRNA and protein levels. The results suggest that by altering chromatin accessibility of the epidermal differentiation complex genes, down-regulation of uc.291 and BRG1 expression contribute to the de-differentiation process seen in keratinocyte malignancy. This provides future direction for the identification of clinical biomarkers in cutaneous SCC. Analysis of publicly available data sets indicates that the above may also be a general feature for SCCs of different origins.

Model-Based Dialysis Adequacy Prediction by Continuous Dialysate Urea Monitoring

A modeling approach for on-line estimation of urea kinetics from continuous measurement of urea concentration in the effluent dialysate stream (DUN) is presented. On-line identification of urea kinetics response parameters is used to predict and update dialysis adequacy during the treatment. Dialysis adequacy can be quantified in several ways, but its strict dependence on final urea concentration is a major fact. For this reason, a good predictive skill on the time course of DUN may enable better performances in the control of dialysis outcome by treatment parameters adjustment. A post-filter enzymatic sensor performs continuous measurement of DUN on patients undergoing standard haemodialysis. To get an early prediction of the end dialysis urea level, the solution of a variable volume double-pool (VVDP) model is used, whose parameters are identified at each time on the basis of the past DUN history. Unlike the variable volume single-pool (VVSP) model, this enables a prompt and accurate estimation of the final DUN. In fact, after 75 min the estimates always differ by less than 10% from the values measured by the sensor at the end of the treatment. Moreover, values predicted by the model in the last hour always lie within 1% of measured final values. Realtime knowledge of an analytic expression for whole DUN time course also enables the accurate prediction of total removed urea, with no need of cumbersome dialysate collection techniques.

On-Line Estimation and Prediction of Urea Kinetics during Hemodialysis: A Simulation Approach

A new method for the on-line estimation of urea kinetic parameters from blood urea concentration (BUN) continuously measured during a dialysis session is proposed. The method, based on the variable-volume double-pool model, is evaluated through a simulation approach in order to easily consider a large set of well-controlled test conditions. The model is characterized by six parameters, knowledge of which enables early prediction of the end dialysis urea concentration and the dose of dialysis. The sensitivity of the model predicted BUN with respect to the parameters was first analyzed to investigate which can be reliably estimated from blood urea measurements taken at a suitable rate. This analysis showed that the model predicted BUN is highly sensitive to the initial blood urea concentration and to the dialyzer clearance, normalized with respect to the total initial distribution volume, while it is scarcely influenced by the normalized ultrafiltration and urea generation rates. The new on-line estimation technique keeps these two last parameters constant and takes advantage of an original analytic solution of the second order urea kinetics. The results of the estimation process on realistic simulated data showed that the proposed method provides early and reliable estimates of the normalized clearance and of the end dialysis concentration. The transcellular mass transfer coefficient and the intra-extra cellular volume ratio can also be estimated, although with less accuracy. Moreover, it was shown that the use of the single-pool model, instead of the double-pool one, provides systematic errors on the estimates.

Comparative Evaluation of Different Methods to Estimate Urea Distribution Volume and Generation Rate

Eight methods to estimate urea distribution volume and generation rate from blood urea samples measured in dialysis patients are reviewed. An analytical solution has been provided for a double-pool variable volume kinetic model to allow for faster and more accurate simulation and identification. The reliable parameter estimates provided by the double-pool kinetic model starting from seven samples, were assumed as references for the estimates obtained by the remaining methods. These include three kinetic models and four methods based on urea mass-balance. In particular, the estimation techniques differ in the number of compartments where urea is assumed distributed (double- and single-pool) or in the number of blood urea samples. Among the methods based on mass-balance, two techniques neglecting the weight loss or the urea generation during dialysis, were also analysed. The results obtained during hemofiltration sessions using three samples, usually available in clinical practice at the beginning and at the end of dialysis, demonstrate that a new method based on double-pool kinetics provides, on average, the most reliable estimates. Moreover, methods belonging to a single pool view and including both weight loss and urea generation during dialysis seem to underestimate by 1÷2 liters the urea distribution volume. However, neglecting the weight loss or the urea generation can overcompensate this error, resulting in a significant overestimation of the distribution volume. Finally, it has been experimentally proved that the single-pool kinetic methods overestimate the urea production rate, while techniques based on mass balance provide more reliable values.

[Retrospective study on the effects of a whey protein concentrate on body composition in 262 sarcopenic tube fed patients]

AIM

As pointed in ESPEN guidelines on the use of bioelectrical impedance analysis (BIA), "body cell mass (BCM) is the protein rich compartment which is affected in catabolic states, and loss of BCM is associated with poor clinical outcome". Whey proteins are known to improve lean mass in many conditions. We retrospectively evaluated the effects of a WP concentrate with high cysteine content (WPHCC) on BCM of 262 sarcopenic tube fed patients (pts).

METHODS

Two hundred sixty-two sarcopenic tube fed pts (130 males, mean age 68,1±15,6 years) were given daily supplemental WPHCC (0.7±0.2 g/kg body weight) after their usual feeding formula, with the aim to improve their BCM. Each patient received a multifrequency impedance test before and after the beginning of WPHCC supplementation (mean follow-up: 4.2±2.8 months). Fifty percent of patients were affected by neurodegenerative diseases, 36% by cancer, 14% by other conditions.

RESULTS

BCM, body weight and fat mass significantly improved (P<0.01) after treatment. No severe side effects were recorded. A slight increase in blood urea was observed.

CONCLUSION

In our population WPHCC have been safe and effective in improving BCM. WPHCC could be useful to improve BCM in sarcopenic tube fed pts, although renal function should be monitored.

The elderly over 90yr affected by deperession post-stroke respond well to antidepressant therapy with SSRI? study on a population admitted in nursing home (RSA)

Introduction

The frailty of elderly in Tenth Decade with stroke was considered a certainty for many years ruling, and the stroke in 90 year old was a paradigm of fragility in gerontology. However soon enough the existing data on the population in nursing homes.

Method

The aim of this study was to evaluate the response to therapy SSRI antidepressants (fluoxetine 20–40 mg; sertraline 25–100 mg,; citalopram 10–40 mg) in a population of olds with depression after-stroke hospitalized in Nursing Home (RSA) at Catania (Sicily). We evaluated a total sample of 66 patients comparing the 13 patients 90yr-old with the 53 patients younger pertaining to the same RSA for stroke.

Results

Stackable with somatic comorbidity and the post-stroke depression between the two populations, we founded:1.

Conclusion

According to this data the response to antidepressants seems to be good and totally overlapped with the population most 'young studied as a reference.

This data also confirms that it is not age itself but the comorbidity of diseases present that make it’ a frail old man and that probably the frailty of the nineties is a biological myth.

Depression and obstructive sleep apnea (OSAS) in the elderly: Study on a population of elderly patients recovered in acute setting

Introduction

The obstructive sleep-apnea (OSAS) is a syndrome common in elderly, dangerous and frequently misunderstood by the superficiality of the evaluation of nonspecific symptoms of onset.

Objectives and aims

In this study we studied the prevalence of sleep-apnea (OSAS) in a sick elderly population admitted to a Acute Geriatrics, the correlation with cardiovascular disease and the effects on performaces psychometric

Methods

62 subjects were examined in Acute Cure of Geriatrics of University of Catania. All subjects, after a careful medical history, were administered MMSE to cognitive and affective aspect for GDS. Also consider the autonomy and self-reliance by Barthel-Index, IADL and ADL. All subjects also performed 24-hour Holter-ECG examination and examination for Holter blood pressure in 24 hours, made basic spirometric assessments and finally carried out the examination with polysomnography VitalNight-8.

Results

The results in this study have ample evidence on the prevalence of OSAS in the elderly population admitted to the ward for acute cases. Shall also be significant correlations with cognitive status and mood, both largely influenced negatively by the presence of OSAS. They seem much more depressed elderly patients with OSAS compared with the general population. Finally, the highly statistically significant correlation with the presence of OSAS arrhythmias, high pressure is not controlled by drug therapy, obesity and Chronic Bronchitis.

Conclusions

This study reports the evidence of higher correlation between OSAS and Depression in population studied. All these data make us conclude the obvious danger of this disease still so 'little studied in the elderly population.

Energetic assessment of trunk postural modifications induced by a wearable audio-biofeedback system

This paper investigates the trunk postural modifications induced by a wearable device which assesses the trunk sway and provides biofeedback information through sonification of trunk kinematics. The device is based on an inertial wearable sensing unit including three mono-axial accelerometers and three rate gyroscopes embedded and mounted orthogonally. The biofeedback device was tested on nine healthy subjects during quiet stance in different conditions of sensory limitation eyes closed on solid surface, eyes open on foam cushion surface, eyes closed on foam cushion surface. Five trials were performed for each condition; the order of the trials was randomized. The results reported in this paper show how subjects reduced their rotational kinetic energy by using the biofeedback information and how this reduction was related to the limitation of sensory information.

Light induced atomic desorption from dry-film coatings

We report the first experimental evidence of nonthermal light induced atomic desorption (LIAD) from octadecyltrichlorosilane dry film. The experiment has been made with Rb confined in a coated cell kept at room temperature. A detailed study of the main features of LIAD effect has been made by varying intensity and wavelength of desorbing light. A discussion about the differences and similarities with other organic films that were studied first is reported. This result is important as it expands the list of materials showing such an effect and increases the possibilities to get suitable light controlled atomic sources for spectroscopy and applications. In particular, we plan to exploit this feature in a Fr magneto-optical trap apparatus.

Human postural response to lower leg muscle vibration of different duration

Body lean response to bilateral vibrations of soleus muscles were investigated in order to understand the influence of proprioceptive input from lower leg in human stance control. Proprioceptive stimulation was applied to 17 healthy subjects by two vibrators placed on the soleus muscles. Frequency and amplitude of vibration were 60 Hz and 1 mm, respectively. Vibration was applied after a 30 s of baseline. The vibration duration of 10, 20, 30 s respectively was used with following 30 s rest. Subjects stood on the force platform with eyes closed. Postural responses were characterized by center of pressure (CoP) displacements in the anterior-posterior (AP) direction. The CoP-AP shifts as well as their amplitudes and velocities were analyzed before, during and after vibration. Vibration of soleus muscles gradually increased backward body tilts. There was a clear dependence of the magnitude of final CoP shift on the duration of vibration. The amplitude and velocity of body sway increased during vibration and amplitude was significantly modulated by duration of vibration as well. Comparison of amplitude and velocity of body sway before and after vibration showed significant post-effects. Presented findings showed that somatosensory stimulation has a long-term, direction-specific influence on the control of postural orientation during stance. Further, the proprioceptive input altered by soleus muscles vibration showed significant changes in postural equilibrium during period of vibration with interesting post-effects also.

MicroCT examination of human bone specimens: effects of polymethylmethacrylate embedding on structural parameters

X-ray microtomography permits the nondestructive investigation of trabecular and cortical bone specimens without special preparation of the sample. To do a quantitative characterization, the cross-section images have to be binarized, separating bone from nonbone. For this purpose, a widely used method is uniform thresholding. However, for commonly available microtomography scanners which use a polychromatic X-ray source, it is unclear what effect the surrounding medium (e.g. air, saline solution, polymethylmethacrylate) has on the threshold value used for the binarization. In the literature an easy procedure to find the optimal uniform threshold value for a given acquisition condition is reported. By applying this procedure, the present work investigated whether a microtomography scan of trabecular bone samples in air or embedded in polymethylmethacrylate gave the same results in terms of structural parameters. The gold standard, that is, histological sections, was used as a reference. Two fixed threshold values were found, one for the microtomography scans performed in air and one for the scans with the same samples embedded in polymethylmethacrylate. These were applied on the correspondent microtomography images for the estimation of structural parameters, such as bone volume fraction, direct trabecular thickness, direct trabecular separation and structure model index. Paired comparisons were made in bone volume fraction between histological sections and microtomography cross-sections for the same bone samples scanned first in air and then embedded in polymethylmethacrylate, by which no significant differences were found. Paired comparisons were also made in bone volume fraction, direct trabecular thickness, direct trabecular separation and structure model index for the same samples over volumes of interest of 4 x 4 x 4 mm3 between microtomography scans in air and scans with the samples embedded in polymethylmethacrylate. Neither these comparisons showed significant differences. This leads to the conclusion that structural parameters estimated by microtomography for human trabecular bone samples scanned either in air or embedded in polymethylmethacrylate are not affected by the surrounding medium (i.e. presence or absence of polymethylmethacrylate), provided that the corresponding optimal threshold value is applied for each acquisition condition.

Device to measure intra-operatively the primary stability of cementless hip stems

The primary stability of cementless prostheses is critical for the long-term outcome of the operation. Surgeons are currently driven only by their experience in evaluating the extent of stem stability achieved. The aim of the present work was to develop a new device that enables the stability of a cementless stem to be quantitatively assessed intraoperatively. The angle of the stem/femur rotation under torsion and the torque are acquired and compared in real-time to a pre-set threshold inferred from the literature. The device indicates whether the stem is stable or not. It was extensively tested and finally validated in vitro on cadaveric and composite femurs hosting different sizes of the same kind of prostheses, implanted with different levels of press-fitting. The overall accuracy (23%) takes into account not only the overall measurement error but also the variability due to differences in bone quality and stem press-fitting. This error was deemed sufficient to discriminate between stable and unstable implants.

A physical phantom for the calibration of three-dimensional X-ray microtomography examination

X-ray microtomography is rapidly gaining importance as a non-destructive investigation technique, especially in the three-dimensional examination of trabecular bone. Appropriate quantitative three-dimensional parameters describing the investigated structure were introduced, such as the model-independent thickness and the structure model index. The first parameter calculates a volume-based thickness of the structure in three dimensions independent of an assumed structure type. The second parameter estimates the characteristic form of which the structure is composed, i.e. whether it is more plate-like, rod-like or even sphere-like. These parameters are now experiencing a great diffusion and are rapidly growing in importance. To measure the accuracy of these three-dimensional parameters, a physical three-dimensional phantom containing different known geometries and thicknesses, resembling those of the examined structures, is needed. Unfortunately, such particular phantoms are not commonly available and neither does a consolidated standard exist. This work describes the realization of a calibration phantom for three-dimensional X-ray microtomography examination and reports an application example using an X-ray microtomography system. The calibration phantom (external size 13 mm diameter, 23 mm height) was based on various aluminium inserts embedded in a cylinder of polymethylmethacrylate. The inserts had known geometries (wires, foils, meshes and spheres) and thicknesses (ranging from 20 microm to 1 mm). The phantom was successfully applied to an X-ray microtomography device, providing imaging of the inserted structures and calculation of three-dimensional parameters such as the model-independent thickness and the structure model index. With the indications given in the present work it is possible to design a similar phantom in a histology laboratory and to adapt it to the requested applications.

Numerical model to predict the longterm mechanical stability of cementless orthopaedic implants

The objective of this research was to develop a purely biomechanical model, intended to predict the long-term secondary stability of the implant starting from the biomechanical stability immediately after the operation. A continuous rule-based adaptation scheme was formulated as a dynamic system, and the work verified if such a model produced unique and clinically meaningful solutions. It also investigated whether this continuous model provided results comparable with those of a simpler, discrete-states model used in a previous study. The proposed model showed stable convergence behaviour with all investigated initial conditions, with oscillatory behaviour limited to the first steps of the simulation. The results obtained with the wide range of initial conditions support the hypothesis of the existence and uniqueness of the solution for all initial conditions. The differences between the continuous model and the simpler and more efficient finite-states model were found to be extremely modest (less than 4% over the predicted bonded area). Because of these minimal differences, the use of the much faster finite-states model is recommended to investigate asymptotic conditions, and the continuous model described should be used to investigate the evolution over time of the adaptive process.

Periodicalin-situ re-calibration of force platforms: A new method for the robust estimation of the calibration matrix

The paper provides a new technique based on a least-squares approach for the accurate estimation of a force platform calibration matrix using simple manual procedures, when the direction of the applied loads cannot be perfectly aligned with the axes of the platform. This new procedure can be applied to all force platforms and allows the combined application of vertical and horizontal forces, both static and time-varying. The robust calibration method includes the angular errors in the least-squares parameter vector, thus reducing the bias in the estimated calibration matrix parameters. The performance of the robust method was compared with the conventional one, using a numerical simulation approach starting from a known calibration matrix. With the conventional approach, in noiseless conditions, the maximum error due to load misalignment (SD = 3 degrees) was 6% for the direct terms and over 10% for the cross-talk terms. With the robust method, these errors reduced to zero and were always below 0.4%, even when realistic noise was superimposed on the measures. With perfectly aligned loads and realistic output noise, the confidence intervals of the calibration matrix parameters were very similar for the two methods, demonstrating that the increased number of parameters did not affect the reliability of the estimate.

Feature selection of stabilometric parameters based on principal component analysis

This study addresses the challenge of identifying the features of the Centre of pressure (COP) trajectory that are most sensitive to postural performance, with the aim of avoiding redundancy and allowing a straightforward interpretation of the results. Postural sway in 50 young, healthy subjects was measured by a force platform. Thirty-seven stabilometric parameters were computed from the one-dimensional and two-dimensional COP time series. After normalisation to the relevant biomechanical factors, by means of multiple regression models, a feature selection process was performed based on principal component analysis. Results suggest that COP two-dimensional time series can be primarily characterised by four parameters, describing the size of the COP path over the support surface; the principal sway direction; and the shape and bandwidth of the power spectral density plot. COP one-dimensional time series (antero-posterior (AP) and medio-lateral (ML)) can be characterised by six parameters describing COP dispersion along the AP direction; mean velocity along the ML and AP directions; the contrast between ML and AP regulatory activity; and two parameters describing the spectral characteristics of the COP along the AP direction. On the basis of the results obtained, some guidelines are suggested for the choice of stabilometric parameters to use, with the aim of promoting standardisation in quantitative posturography.

Comparison of logistic and Bayesian classifiers for evaluating the risk of femoral neck fracture in osteoporotic patients

Femoral neck fracture prediction is an important social and economic issue. The research compares two statistical methods for the classification of patients at risk for femoral neck fracture: multiple logistic regression and Bayes linear classifier. The two approaches are evaluated for their ability to separate femoral neck fractured patients from osteoporotic controls. In total, 272 Italian women are studied. Densitometric and geometric measurements are obtained from the proximal femur by dual energy X-ray absorptiometry. The performances of the two methods are evaluated by accuracy in the classification and receiver operating characteristic curves. The Bayes classifier achieves an accuracy approximately 1% higher than that of the multiple logistic regression. However, the performances of the two methods, evaluated by the area under the curves, are not statistically different. The study demonstrates that the Bayes linear classifier can be a valid alternative to multiple logistic regression in the classification of osteoporotic patients.

Border-tracing algorithm implementation for the femoral geometry reconstruction

In some orthopaedic applications such as the design of custom-made hip prostheses, reconstruction of the bone morphology is a fundamental step. Different methods are available to extract the geometry of the femoral medullary canal from computed tomography (CT) images. In this research, an automatic procedure (border-tracing method) for the extraction of bone contours was implemented and validated. A composite replica of the human femur was scanned and the CT images processed using three different methods, a manual procedure; the border-tracing algorithm; and a threshold-based method. The resulting contours were used to estimate the accuracy of the implemented procedure. The two software techniques were more accurate than the manual procedure. Then, these two procedures were applied to an in vivo CT data set in order to determine to most critical region for repeatability. Only for the images located in this region, the repeatability measurement was carried out for six in vivo CT data sets to evaluate the inter-femur repeatability. The border-tracing method was found to achieve the highest repeatability.

HIDE: a new hybrid environment for the design of custom-made hip prosthesis

This technical note describes a new software environment (HIPCOM design environment, HIDE) for the design of custom-made total hip replacements. These devices are frequently designed using general-purpose mechanical computer-aided design (CAD) programs using a set of bone contours extracted from the computer tomography (CT) images as anatomical reference. On the contrary, the HIDE system was developed to let the operator directly design the stem shape onto the CT images in a single-step operation. The operator can directly import CT data in DICOM format or use special functions to reconvert to a digital stack, the CT images printed on a radiological film. Once the stack of CT images is loaded, the operator can design the implant shape by imposing control sections directly on the CT images. The interpolation of these control sections produces the basic 3D shape of the custom-made stem. The shape is then exported to the CAD-computer-aided manufacturing (CAM) program to refine the design and to generate the part program to manufacture the implant with a CNC tooling machine. Using HIDE, the duration of design steps it affected was reduced by more than 50% with respect to the standard method in use at the manufacturer site. HIDE also improved the accuracy and the repeatability of the whole procedure. The learning curve became flat after only ten cases. These good results were achieved because of the integration of the vectorial description of the prosthetic component with the raster description of the CT data that allowed the designer to use all details available in the CT images.

Fracture prediction for the femoral neck using finite element models

Fracture of the femoral neck is an important clinical, social and economic topic. Prediction in subjects who are at risk for this type of fracture has been the object of numerous studies. Nonetheless, the methods of classification based on densitometric indicators alone have shown poor accuracy. It is the purpose of this study to propose a method to obtain an estimate of the resistance of the proximal femur, and to improve accuracy in prediction in subjects who are at risk for fracture. Based on the densitometric dataset alone, a bidimensional finite element model was developed that takes into account the distribution of density together with the femoral anatomy and the typical conditions of trauma. The model was applied to a group of preliminary osteoporotic patients. The statistical classification showed an increase in accuracy by 13%, as compared to a classification based on densitometric indicators alone.