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1.
Annu Int Conf IEEE Eng Med Biol Soc ; 2022: 794-797, 2022 07.
Article in English | MEDLINE | ID: mdl-36085983

ABSTRACT

This study investigates the influence of visual noise on motor performance in three degrees of freedom (DoFs) tracking task including translation against gravity and rotation. Participants were asked to follow a moving target, visually degraded according to four different levels of noise, plus one no-noise condition. Each noise level was represented with ten target replicas normally distributed around the main target's pose with a specific standard deviation. Performance, in term of error between cursor and target, significantly decreased (p < 0.001) with the increase of the standard deviation of the visual noise, in all movement directions. The relation between the level of visual noise and the performance appears to be linear (R2 > 0.8) for each DoF separately, as well as when we combine the translations using the Euclidean norm.


Subject(s)
Noise , Humans
2.
Annu Int Conf IEEE Eng Med Biol Soc ; 2022: 2870-2873, 2022 07.
Article in English | MEDLINE | ID: mdl-36086036

ABSTRACT

Tele-operational tasks often suffer from instability issues and limited reliability during unpredictable interactions. We propose a real-time control law reproducing the impedance and kinematic behaviour of a subject's arm (shoulder and elbow) on a remote avatar in a 2-DoF task. The human arm impedance and kinematics are estimated respectively from EMG and M-IMU data and then mapped into the avatar arm through an impedance control. Contrary to literature methods, our portable tele-impedance controller relies only on wearable sensors and enables an easy use in unstructured environments. The good performance (R2> 0.7) of the muscle model used to map on the robot the human stiffness of five healthy subjects indicates the possibility of applying the proposed algorithm for a tele-impedance control.


Subject(s)
Shoulder , Wearable Electronic Devices , Biomechanical Phenomena/physiology , Electric Impedance , Humans , Reproducibility of Results
3.
Sci Rep ; 11(1): 9511, 2021 05 04.
Article in English | MEDLINE | ID: mdl-33947906

ABSTRACT

The successful completion of complex tasks like hanging a picture or laparoscopic surgery requires coordinated motion of more than two limbs. User-controlled supernumerary robotic limbs (SL) have been proposed to bypass the need for coordination with a partner in such tasks. However, neither the capability to control multiple limbs alone relative to collaborative control with partners, nor how that capability varies across different tasks, is well understood. In this work, we present an investigation of tasks requiring three-hands where the foot was used as an additional source of motor commands. We considered: (1) how does simultaneous control of three hands compare to a cooperating dyad; (2) how this relative performance was altered by the existence of constraints emanating from real or virtual physical connections (mechanical constraints) or from cognitive limits (cognitive constraints). It was found that a cooperating dyad outperformed a single user in all scenarios in terms of task score, path efficiency and motion smoothness. However, while the participants were able to reach more targets with increasing mechanical constraints/decreasing number of simultaneous goals, the relative difference in performance between a dyad and a participant performing trimanual activities decreased, suggesting further potential for SLs in this class of scenario.


Subject(s)
Hand/physiology , Psychomotor Performance/physiology , Adult , Female , Foot/physiology , Humans , Laparoscopy/methods , Robotics/methods , Task Performance and Analysis , User-Computer Interface
4.
IEEE Trans Biomed Eng ; 68(5): 1589-1600, 2021 05.
Article in English | MEDLINE | ID: mdl-33513096

ABSTRACT

OBJECTIVE: This article presents the development and validation of a new robotic system for Transcranial Magnetic Stimulation (TMS), characterized by a new control approach, and an ad-hoc calibration methodology, specifically devised for the TMS application. METHODS: The robotic TMS platform is composed of a 7 dof manipulator, controlled by an impedance control, and a camera-based neuronavigation system. The proposed calibration method was optimized on the workspace useful for the specific TMS application (spherical shell around the subject's head), and tested on three different hand-eye and robot-world calibration algorithms. The platform functionality was tested on six healthy subjects during a real TMS procedure, over the left primary motor cortex. RESULTS: employing our method significantly decreases ( ) the calibration error by 34% for the position and 19% for the orientation. The robotic TMS platform achieved greater orientation accuracy than the expert operators, significantly reducing orientation errors by 46% ( ). No significant differences were found in the position errors and in the amplitude of the motor evoked potentials (MEPs) between the robot-aided TMS and the expert operators. CONCLUSION: The proposed calibration represents a valid method to significantly reduce the calibration errors in robot-aided TMS applications. Results showed the efficacy of the proposed platform (including the control algorithm) in administering a real TMS procedure, achieving better coil positioning than expert operators, and similar results in terms of MEPs. SIGNIFICANCE: This article spotlights how to improve the performance of a robotic TMS platform, providing a reproducible and low-cost alternative to the few devices commercially available.


Subject(s)
Robotics , Transcranial Magnetic Stimulation , Calibration , Evoked Potentials, Motor , Humans , Neuronavigation
5.
J Biol Regul Homeost Agents ; 34(4 Suppl. 3): 315-326. Congress of the Italian Orthopaedic Research Society, 2020.
Article in English | MEDLINE | ID: mdl-33261296

ABSTRACT

The conventional use of prosthetic custom-design socket is affected by discomfort related to wellknown problems: sweating, sores or skin irritation, excessive weight and harness, impaired body image, that lead to a high rate of abandonment. Osseointegrated prosthetic implants for limb amputation are progressively evolving to overcome limitations of socket. The aim of this article is to present a systematic review of the use, safety in terms of rate of infection and complications, and reported outcomes of upper and lower limb osseointegrated prosthetic implants. A systematic search was carried out for studies that evaluated outcomes of osseointegration technique in case of upper and lower limb amputees according to the PRISMA guidelines with a PRISMA checklist and algorithm. MINORS score was used for methodologic assessment. 17 articles about the treatment of patients with upper or lower limb amputation treated with an osseointegrated prostesis were included. The overall rate of infections was 32%. All the clinical outcomes reported were related to lower limb. No clinical data for upper limb was found. The postoperative mean value of MCS and PCS SF-36 and Q-TFA was 55.1, 45.4 and 73.8 respectively, while six minute walk test (6MWT) and the timed up and go (TUG) test scored an average value of 388 meters and 11.5 seconds respectively. MINORS score ranged from 5 to 13, with a median of 11 [interquartile range (IQR), 9-11]. The osseointegration is associated to a high rate of postoperative complications but, significant improvement in clinical outcomes compared to preoperative time are shown. The data available from the literature are limited but suggest good clinical outcomes and significant survivorship of the implants. Further clinical studies are needed to establish which kind of implant is associated to higher clinical performance and lower rate of postoperative complications and infections.


Subject(s)
Amputees , Artificial Limbs , Amputation, Surgical , Humans , Osseointegration , Postoperative Complications , Prosthesis Implantation/adverse effects , Treatment Outcome , Upper Extremity
6.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 3232-3235, 2020 07.
Article in English | MEDLINE | ID: mdl-33018693

ABSTRACT

Movement control process can be considered to take place on at least two different levels: a high, more cognitive level and a low, sensorimotor level. On a high level processing a motor command is planned accordingly to the desired goal and the sensory afference, mainly proprioception, is used to determine the necessary adjustments in order to minimize any discrepancy between predicted and executed action. On a lower level processing, the proprioceptive feedback later employed in high level regulations, is generated by Ia sensory fibers positioned in muscle main proprioceptors: muscle spindles. By entraining the activity of these spindle fibers through 80Hz vibration of triceps distal tendon, we show the intriguing possibility of inducing kinematics adjustments due to negative feedback corrections, during a lifting task.


Subject(s)
Feedback, Sensory , Lifting , Biomechanical Phenomena , Movement , Proprioception
7.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 3244-3247, 2020 07.
Article in English | MEDLINE | ID: mdl-33018696

ABSTRACT

A unique virtual reality platform for multisensory integration studies is presented. It allows to provide multimodal sensory stimuli (i.e. auditory, visual, tactile, etc.) ensuring temporal coherence, key factor in cross-modal integration. Four infrared cameras allow to real-time track the human motion and correspondingly control a virtual avatar. A user-friendly interface allows to manipulate a great variety of features (i.e. stimulus type, duration and distance from the participants' body, as well as avatar gender, height, arm pose, perspective, etc.) and to real-time provide quantitative measures of all the parameters. The platform has been validated on two healthy participants testing a reaction time task which combines tactile and visual stimuli, for the investigation of peripersonal space. Results proved the effectiveness of the proposed platform, showing a significant correlation (p=0.013) between the participant's hand distance from the visual stimulus and the reaction time to the tactile stimulus. More participants will be recruited to further investigate the other measures provided by the platform.


Subject(s)
Touch Perception , Virtual Reality , Hand , Humans , Personal Space , Touch
8.
Cogn Neurosci ; 11(4): 216-228, 2020.
Article in English | MEDLINE | ID: mdl-32748685

ABSTRACT

Over a lifetime of experience, the representation of the body is built upon congruent integration of multiple elements constituting the sensorimotor loop. To investigate its robustness against the rupture of congruency between senses and with motor command, we selectively manipulated in healthy subjects the binds between sight, proprioception, and efferent motor command. Two experiments based on the Moving Hand Illusion were designed employing Tendon Vibration Illusion to modulate proprioception and generate illusory altered feedback of movement. In Experiment A, visuomotor congruency was modulated by introducing adelay between complex multifingered movements performed by arobotic hand and real movement of each participant's hand. In the presence of the motor command, visuomotor congruency enhanced ownership, agency, and skin conductance, while proprioceptive-motor congruency was not effective, confirming the prevalence of vision upon proprioception. In Experiment B, the impact of visuo-proprioceptive congruency was tested in the absence of motor command because the robotic hand moved autonomously. Intersensory congruency compensated for the absence of motor command only for ownership. Skin conductance in Exp Band Proprioceptive Drift in both experiments did not change. Results suggest that ownership and agency are independently processed, and presence of the efferent component modulates sensory feedbacks salience. The brain seems to require the integration of at least two streams of congruent information. Bodily awareness can be generated from sensory information alone, but to feel in charge of the body, senses must be double-checked with the prediction generated from efference copy, which is treated as an additional sensory modality.


Subject(s)
Feedback, Sensory/physiology , Galvanic Skin Response/physiology , Hand/physiology , Illusions/physiology , Motor Activity/physiology , Proprioception/physiology , Psychomotor Performance/physiology , Adult , Female , Humans , Male , Robotics , Young Adult
9.
Cell Rep ; 30(5): 1400-1416.e6, 2020 02 04.
Article in English | MEDLINE | ID: mdl-32023458

ABSTRACT

The use of cetuximab anti-epidermal growth factor receptor (anti-EGFR) antibodies has opened the era of targeted and personalized therapy in colorectal cancer (CRC). Poor response rates have been unequivocally shown in mutant KRAS and are even observed in a majority of wild-type KRAS tumors. Therefore, patient selection based on mutational profiling remains problematic. We previously identified methylglyoxal (MGO), a by-product of glycolysis, as a metabolite promoting tumor growth and metastasis. Mutant KRAS cells under MGO stress show AKT-dependent survival when compared with wild-type KRAS isogenic CRC cells. MGO induces AKT activation through phosphatidylinositol 3-kinase (PI3K)/mammalian target of rapamycin 2 (mTORC2) and Hsp27 regulation. Importantly, the sole induction of MGO stress in sensitive wild-type KRAS cells renders them resistant to cetuximab. MGO scavengers inhibit AKT and resensitize KRAS-mutated CRC cells to cetuximab in vivo. This study establishes a link between MGO and AKT activation and pinpoints this oncometabolite as a potential target to tackle EGFR-targeted therapy resistance in CRC.


Subject(s)
Cetuximab/therapeutic use , Colorectal Neoplasms/drug therapy , Free Radical Scavengers/pharmacology , Mutation/genetics , Proto-Oncogene Proteins p21(ras)/genetics , Pyruvaldehyde/pharmacology , Adult , Aged , Aged, 80 and over , Animals , Carnosine/pharmacology , Cell Line, Tumor , Cell Proliferation/drug effects , Cetuximab/pharmacology , Clone Cells , Enzyme Activation/drug effects , Glycolysis/drug effects , Glycosylation/drug effects , HSP27 Heat-Shock Proteins/metabolism , Humans , Male , Mechanistic Target of Rapamycin Complex 2/metabolism , Mice, Inbred NOD , Mice, SCID , Middle Aged , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Stress, Physiological/drug effects
10.
Sci Rep ; 9(1): 19030, 2019 12 13.
Article in English | MEDLINE | ID: mdl-31836765

ABSTRACT

Humans increasingly often act through virtual and robotic avatars, which can feed back to their user only virtual sensory information. Since avatar is user's embodiment and body image is mostly based on senses, how virtualization of sensory inputs affects avatar self-attribution is a key question for understanding nowadays human behavior. By manipulating visual and tactile inputs in a series of experiments fashioned after the rubber hand illusion, we assessed the relative weight of the virtualization of sight (Real, Robotic, Virtual) and of touch (Real, Virtual) on artificial hand embodiment. Virtualization decreased embodiment, but unexpectedly lowest embodiment was found when only one sense was virtual. Discordant levels of virtualization of sight and touch elicited revulsion, extending the concept of the uncanny valley to avatar embodiment. Besides timing, spatial constraints and realism of feedback, a matched degree of virtualization of seen and felt stimuli is a further constraint in building the representation of the body.

11.
J R Soc Interface ; 16(158): 20190262, 2019 09 27.
Article in English | MEDLINE | ID: mdl-31506046

ABSTRACT

Increasing evidence suggests that responsiveness is associated with critical or near-critical cortical dynamics, which exhibit scale-free cascades of spatio-temporal activity. These cascades, or 'avalanches', have been detected at multiple scales, from in vitro and in vivo microcircuits to voltage imaging and brain-wide functional magnetic resonance imaging (fMRI) recordings. Criticality endows the cortex with certain information-processing capacities postulated as necessary for conscious wakefulness, yet it remains unknown how unresponsiveness impacts on the avalanche-like behaviour of large-scale human haemodynamic activity. We observed a scale-free hierarchy of co-activated connected clusters by applying a point-process transformation to fMRI data recorded during wakefulness and non-rapid eye movement (NREM) sleep. Maximum-likelihood estimates revealed a significant effect of sleep stage on the scaling parameters of the cluster size power-law distributions. Post hoc statistical tests showed that differences were maximal between wakefulness and N2 sleep. These results were robust against spatial coarse graining, fitting alternative statistical models and different point-process thresholds, and disappeared upon phase shuffling the fMRI time series. Evoked neural bistabilities preventing arousals during N2 sleep do not suffice to explain these differences, which point towards changes in the intrinsic dynamics of the brain that could be necessary to consolidate a state of deep unresponsiveness.


Subject(s)
Brain , Cerebrovascular Circulation/physiology , Electroencephalography , Hemodynamics/physiology , Magnetic Resonance Imaging , Sleep, Slow-Wave/physiology , Wakefulness/physiology , Brain/blood supply , Brain/diagnostic imaging , Brain/physiology , Female , Humans
12.
Article in English | MEDLINE | ID: mdl-30949403

ABSTRACT

In this paper we compare three approaches to solve the hand-eye and robot-world calibration problem, for their application to a Transcranial Magnetic Stimulation (TMS) system. The selected approaches are: i) non-orthogonal approach (QR24); ii) stochastic global optimization (SGO); iii) quaternion-based (QUAT) method. Performance were evaluated in term of translation and rotation errors, and computational time. The experimental setup is composed of a 7 dof Panda robot (by Franka Emika GmbH) and a Polaris Vicra camera (by Northern Digital Inc) combined with the SofTaxic Optic software (by E.M.S. srl). The SGO method resulted to have the best performance, since it provides lowest errors and high stability over different datasets and number of calibration points. The only drawback is its computational time, which is higher than the other two, but this parameter is not relevant for TMS application. Over the different dataset used in our tests, the small workspace (sphere with radius of 0.05m) and a number of calibration points around 150 allow to achieve the best performance with the SGO method, with an average error of 0.83 ± 0.35mm for position and 0.22 ± 0.12deg for orientation.

13.
J Biol Regul Homeost Agents ; 31(4 suppl 1)2017.
Article in English | MEDLINE | ID: mdl-29188681

ABSTRACT

Targeted muscle reinnervation (TMR) is a novel surgical technique developed to improve the control of myoelectric upper limb prostheses. Nerves transected by the amputation, which retain their original motor pathways even after being severed, are redirected to residual denervated muscles that serve as target for consequent reinnervation. Once the process is complete, reinnervated muscles will contract upon voluntary activation of transferred nerves while attempting to move missing regions of the amputated limb, generating EMG signals that can be recorded and used to control a prosthetic device. This allows creating new control sites that can overcome major drawbacks of conventional myoelectric prostheses by offering a more natural and intuitive control of prosthetic arms. TMR has been widely performed in individuals who underwent shoulder disarticulation amputation and transhumeral amputation since proximal amputations do not leave enough functional muscles exploitable to control independent degree of freedoms of multi-articulated prostheses. TMR application is currently under investigation in patients suffering further distal amputations, as well as for treating and preventing painful post-amputation neuromas. The purpose of this paper is to describe the physiologic basis and the surgical technique of TMR, reporting current knowledge on the clinical results.

14.
IEEE Int Conf Rehabil Robot ; 2017: 1556-1561, 2017 07.
Article in English | MEDLINE | ID: mdl-28814041

ABSTRACT

Parkinson's disease (PD) is a neurodegenerative brain disorder that slowly brings on the dopaminergic neurons death. The depletion of the dopaminergic signal causes the onset of motor symptoms such as tremor, bradykinesia and rigidity. Usually, neurologists regularly monitor motor symptoms and motor fluctuations using the MDS-UPDRS part III clinical scale. Nevertheless, to have a more objective and quantitative evaluation, it is possible to assess the cardinal motor symptoms of PD using wearable sensors and portable robotic devices. Unfortunately while there are several research papers on the use of these devices on PD patients, their use is not so common in clinical practice. In this work we recorded specific MDS-UPDRS motor tasks using magneto-inertial devices, worn by seven PD subjects and seven age-matched controls, in order to deeply analyze the kinematic and dynamic characteristics of goal-directed movements of upper limb, in addition to extract quantitative indices (peak velocity, smoothness, etc) useful for the assessment of motor symptoms. Using only gyroscope signals we looked at those parameters useful to assess bradykinesia. We observed parameters changes from OFF to ON phase congruent with the MDS-UPDRS changes, especially in the frequency domain. Our results suggest the prono-supination task is the more consistent to describe the bradykinesia symptom with the gyroscopes. Probably because of the amplitude of the movement performed. Moreover the peak power looks appropriate for bradykinesia symptom evaluation. We can conclude that, similar to the studies in which tremor symptom is evaluated, it is possible to monitor the bradykinesia using few wearable sensors and few simple parameters.


Subject(s)
Accelerometry/methods , Hypokinesia , Parkinson Disease , Signal Processing, Computer-Assisted , Aged , Arm/physiopathology , Female , Humans , Hypokinesia/classification , Hypokinesia/diagnosis , Hypokinesia/physiopathology , Male , Middle Aged , Parkinson Disease/classification , Parkinson Disease/diagnosis , Parkinson Disease/physiopathology , Task Performance and Analysis
15.
ROMAN ; 2017: 156-161, 2017 Aug 01.
Article in English | MEDLINE | ID: mdl-30949293

ABSTRACT

In this paper we propose and validate a teleoperated control approach for an anthropomorphic redundant robotic manipulator, using magneto-inertial sensors (IMUs). The proposed method allows mapping the motion of the human arm (used as the master) on the robot end-effector (the slave). We record arm movements using IMU sensors, and calculate human forward kinematics to be mapped on robot movements. In order to solve robot kinematic redundancy, we implemented different algorithms for inverse kinematics that allows imposing anthropomorphism criteria on robot movements. The main objective is to let the user to control the robotic platform in an easy and intuitive manner by providing the control input freely moving his/her own arm and exploiting redundancy and anthropomorphism criteria in order to achieve human-like behaviour on the robot arm. Therefore, three inverse kinematics algorithms are implemented: Damped Least Squares (DLS), Elastic Potential (EP) and Augmented Jacobian (AJ). In order to evaluate the performance of the algorithms, four healthy subjects have been asked to control the motion of an anthropomorphic robot arm (i.e. the Kuka Light Weight Robot 4+) through four magneto-inertial sensors (i.e. Xsens Wireless Motion Tracking sensors - MTw) positioned on their arm. Anthropomorphism indices and position and orientation errors between the human hand pose and the robot end-effector pose were evaluated to assess the performance of our approach.

16.
Brain Stimul ; 10(1): 1-18, 2017.
Article in English | MEDLINE | ID: mdl-27931886

ABSTRACT

BACKGROUND: In recent years, many studies have evaluated the effects of noninvasive brain stimulation (NIBS) techniques for the treatment of several neurological and psychiatric disorders. Positive results led to approval of NIBS for some of these conditions by the Food and Drug Administration in the USA. The therapeutic effects of NIBS have been related to bi-directional changes in cortical excitability with the direction of change depending on the choice of stimulation protocol. Although after-effects are mostly short lived, complex neurobiological mechanisms related to changes in synaptic excitability bear the potential to further induce therapy-relevant lasting changes. OBJECTIVE: To review recent neurobiological findings obtained from in vitro and in vivo studies that highlight molecular and cellular mechanisms of short- and long-term changes of synaptic plasticity after NIBS. FINDINGS: Long-term potentiation (LTP) and depression (LTD) phenomena by itself are insufficient in explaining the early and long term changes taking place after short episodes of NIBS. Preliminary experimental studies indicate a complex scenario potentially relevant to the therapeutic effects of NIBS, including gene activation/regulation, de novo protein expression, morphological changes, changes in intrinsic firing properties and modified network properties resulting from changed inhibition, homeostatic processes and glial function. CONCLUSIONS: This review brings into focus the neurobiological mechanisms underlying long-term after-effects of repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS) recently obtained from in vitro and in vivo studies, both in animals and humans.


Subject(s)
Brain/physiology , Mental Disorders/therapy , Transcranial Direct Current Stimulation/trends , Transcranial Magnetic Stimulation/trends , Animals , Depression/diagnosis , Depression/physiopathology , Depression/therapy , Humans , Long-Term Potentiation/physiology , Mental Disorders/diagnosis , Mental Disorders/physiopathology , Neuronal Plasticity/physiology , Stereotaxic Techniques/trends , Transcranial Direct Current Stimulation/methods , Transcranial Magnetic Stimulation/methods
17.
Transplant Proc ; 48(9): 2931-2937, 2016 Nov.
Article in English | MEDLINE | ID: mdl-27932110

ABSTRACT

BACKGROUND: Kidney transplant patients with D+/R+ serology can be treated with either prophylaxis or preemptive valganciclovir. The older transplant population suffers severe immunosenescence, especially patients with latent cytomegalovirus (CMV) infection (R+). They are more likely to develop indirect CMV effects. Likewise, many patients have significant cardiovascular comorbidity, which makes them more sensitive to these indirect effects. The aim of this study was to evaluate the incidence of CMV viremia and indirect effects on survival, comparing prophylaxis (V) against preemptive (P) valganciclovir in an older kidney transplant population. METHODS: We analyzed the data of 233 recipients from 2002 (age, >55 years; D+/R+) with ≥6 months of follow-up. The patients were divided into 2 groups: 167 (71.7%) in the V group and 66 (28.3%) in the P group. RESULTS: The incidence of CMV infection in the P group was 32% versus 6% in V group. Patients with CMV viremia showed worse survival values than patients without viremia (log rank P = .031). Five-year survivals were 74% vs 88%, respectively. Cox regression showed that the adjusted effect of CMV infection on overall survival was a significant risk (hazard ratio [HR], 2.07; 95% CI, 1.003-4.29). Patients with CMV viremia showed worse cardiovascular survival than patients without viremia, with 5-year survivals of 79% vs 94%. Cox regression showed that the adjusted effect of CMV infection was a significant risk (HR, 2.62). CONCLUSIONS: CMV infection has a detrimental effect on the survival of older patients. Valganciclovir prophylaxis induces a protective effect against CMV infection and could improve survival of older patients with cardiovascular comorbidities.


Subject(s)
Antiviral Agents/therapeutic use , Cytomegalovirus Infections/prevention & control , Ganciclovir/analogs & derivatives , Cytomegalovirus/immunology , Cytomegalovirus Infections/mortality , Epidemiologic Methods , Female , Ganciclovir/therapeutic use , Humans , Kidney Transplantation/adverse effects , Kidney Transplantation/mortality , Male , Middle Aged , Recurrence , Time Factors , Valganciclovir , Viremia/etiology , Viremia/mortality , Viremia/prevention & control
18.
Phys Chem Chem Phys ; 18(45): 31260-31267, 2016 Nov 16.
Article in English | MEDLINE | ID: mdl-27819104

ABSTRACT

The gas phase structure and excited state lifetime of the p-aminophenolp-cresol heterodimer have been investigated by REMPI and LIF spectroscopy with nanosecond laser pulses and pump-probe experiments with picosecond laser pulses as a model system to study the competition between π-π and H-bonding interactions in aromatic dimers. The excitation is a broad and unstructured band. The excited state of the heterodimer is long lived (2.5 ± 0.5) ns with a very broad fluorescence spectrum red-shifted by 4000 cm-1 with respect to the excitation spectrum. Calculations at the MP2/RI-CC2 and DFT-ωB97X-D levels indicate that hydrogen-bonded (HB) and π-stacked isomers are almost isoenergetic in the ground state while in the excited state only the π-stacked isomer exists. This suggests that the HB isomer cannot be excited due to negligible Franck-Condon factors and therefore the excitation spectrum is associated with the π-stacked isomer that reaches vibrationally excited states in the S1 state upon vertical excitation. The excited state structure is an exciplex responsible for the fluorescence of the complex. Finally, a comparison was performed between the π-stacked structure observed for the p-aminophenolp-cresol heterodimer and the HB structure reported for the (p-cresol)2 homodimer indicating that the differences are due to different optical properties (oscillator strengths and Franck-Condon factors) of the isomers of both dimers and not to the interactions involved in the ground state.

19.
PLoS Med ; 12(9): e1001871, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26327350

ABSTRACT

BACKGROUND: Breast cancer is a leading malignancy affecting the female population worldwide. Most morbidity is caused by metastases that remain incurable to date. TGF-ß1 has been identified as a key driving force behind metastatic breast cancer, with promising therapeutic implications. METHODS AND FINDINGS: Employing immunohistochemistry (IHC) analysis, we report, to our knowledge for the first time, that asporin is overexpressed in the stroma of most human breast cancers and is not expressed in normal breast tissue. In vitro, asporin is secreted by breast fibroblasts upon exposure to conditioned medium from some but not all human breast cancer cells. While hormone receptor (HR) positive cells cause strong asporin expression, triple-negative breast cancer (TNBC) cells suppress it. Further, our findings show that soluble IL-1ß, secreted by TNBC cells, is responsible for inhibiting asporin in normal and cancer-associated fibroblasts. Using recombinant protein, as well as a synthetic peptide fragment, we demonstrate the ability of asporin to inhibit TGF-ß1-mediated SMAD2 phosphorylation, epithelial to mesenchymal transition, and stemness in breast cancer cells. In two in vivo murine models of TNBC, we observed that tumors expressing asporin exhibit significantly reduced growth (2-fold; p = 0.01) and metastatic properties (3-fold; p = 0.045). A retrospective IHC study performed on human breast carcinoma (n = 180) demonstrates that asporin expression is lowest in TNBC and HER2+ tumors, while HR+ tumors have significantly higher asporin expression (4-fold; p = 0.001). Assessment of asporin expression and patient outcome (n = 60; 10-y follow-up) shows that low protein levels in the primary breast lesion significantly delineate patients with bad outcome regardless of the tumor HR status (area under the curve = 0.87; 95% CI 0.78-0.96; p = 0.0001). Survival analysis, based on gene expression (n = 375; 25-y follow-up), confirmed that low asporin levels are associated with a reduced likelihood of survival (hazard ratio = 0.58; 95% CI 0.37-0.91; p = 0.017). Although these data highlight the potential of asporin to serve as a prognostic marker, confirmation of the clinical value would require a prospective study on a much larger patient cohort. CONCLUSIONS: Our data show that asporin is a stroma-derived inhibitor of TGF-ß1 and a tumor suppressor in breast cancer. High asporin expression is significantly associated with less aggressive tumors, stratifying patients according to the clinical outcome. Future pre-clinical studies should consider options for increasing asporin expression in TNBC as a promising strategy for targeted therapy.


Subject(s)
Breast Neoplasms/drug therapy , Breast Neoplasms/metabolism , Extracellular Matrix Proteins/metabolism , Extracellular Matrix Proteins/pharmacology , Animals , Biomarkers, Tumor/metabolism , Blotting, Western , Enzyme-Linked Immunosorbent Assay , Female , Fibroblast Growth Factors/metabolism , Fibroblast Growth Factors/pharmacology , Fibroblasts/metabolism , Gene Expression Regulation, Neoplastic , Heterografts , Humans , Interleukin-1beta/pharmacology , Mice , Middle Aged , Prognosis , Real-Time Polymerase Chain Reaction , Retrospective Studies , Survival Analysis , Transforming Growth Factor beta/pharmacology , Tumor Cells, Cultured
20.
Musculoskelet Surg ; 99(3): 179-87, 2015 Dec.
Article in English | MEDLINE | ID: mdl-25860499

ABSTRACT

The aim of this review is to collect and discuss the current best evidence published in literature about the effect of the Masai Barefoot Technology(MBT) shoes on gait and muscle activation and try to draw conclusions on the possible benefits. We searched Medline, CINAHL, Embase and the Cochrane Central Registry of Controlled Trials. The reference lists of the previously selected articles were then examined by hand. Only studies comparing biomechanical and clinical outcomes were selected. Review, anatomical studies, letter to editor and instructional course were excluded. Finally, all the resulting articles were reviewed and discussed by all the authors to further confirm their suitability for this review: in the end, 22 articles were included. A total of 532 patients presenting a mean age of 34.3 years were studied. All patients evaluated were healthy or amateur sports except in two studies where only obese subjects and knee osteoarthritis patients were involved. Seven studies evaluated only male subjects, whereas four studies evaluated only female. Twelve of twenty-two studies performed electromyographic analyses. Weight was reported in 19 studies, whereas body mass index were reported only in a five studies. All studies reported kinematic analysis of shoe effects and compared the relationship between muscle recruitment and electromyographic activity. Unstable footwears were shown to immediately alter the stability in gait during daily-life activities. The center of body pressure is moved posteriorly with a consequent posterior displacement of the upper part of body in order to regain an appropriate body balance, and these postural changes are associated with an overall increase in the activity of lumbar erector spine muscles, as well as certain lower limb muscles. Current literature provides enough cues to conclude for a beneficial role of MBT shoes in the postural and proprioceptive recovery, but from the same literature cannot be drown clear and appropriate guidance to determine more in detail their indication for specific pathological conditions or for particular phases of the musculoskeletal recovery process.


Subject(s)
Biomechanical Phenomena , Gait , Range of Motion, Articular , Shoes , Walking , Electromyography , Evidence-Based Medicine , Humans , Postural Balance , Time Factors
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