A novel environmental chamber for neuronal network multisite recordings.

Environmental stability is a critical issue for neuronal networks in vitro. Hence, the ability to control the physical and chemical environment of cell cultures during electrophysiological measurements is an important requirement in the experimental design. In this work, we describe the development and the experimental verification of a closed chamber for multisite electrophysiology and optical monitoring. The chamber provides stable temperature, pH and humidity and guarantees cell viability comparable to standard incubators. Besides, it integrates the electronics for long-term neuronal activity recording. The system is portable and adaptable for multiple network housings, which allows performing parallel experiments in the same environment. Our results show that this device can be a solution for long-term electrophysiology, for dual network experiments and for coupled optical and electrical measurements.

Vitality form expression in autism.

The notion of "vitality form" has been coined by Daniel Stern to describe the basic features of action, which may reflect the mood or affective state of an agent. There is general consensus that vitality forms substantiate social interactions in children as well in adults. Previous studies have explored children with Autism Spectrum Disorder (ASD)'s ability in copying and recognizing the vitality forms of actions performed by others. In this paper we investigated, for the first time, how children with ASD express different vitality forms when acting themselves. We recorded the kinematics of ASD and typically developing (TD) children while performing three different types of action with two different vitality forms. There were two conditions. In the what condition we contrasted the three different types of action performed with a same vitality form, while in the how condition we contrasted the same type of action performed with two different vitality forms. The results showed a clear difference between ASD children and TD children in the how, but not in the what, condition. Indeed, while TD children distinguished the vitality forms to be expressed by mostly varying a specific spatiotemporal parameter (i.e. movement time), no significant variation in this parameter was found in ASD children. As they are not prone to express vitality forms as neurotypical individuals do, individuals with ASD's interactions with neurotypical peers could therefore be difficult to achieve successfully, with cascading effects on their propensity to be tuned to their surrounding social world, or so we conjecture. If this conjecture would turn out to be correct, our findings could have promising implication for theoretical and clinical research in the context of ASD.

Upper-limb actuated exoskeleton for muscular dystrophy patients: preliminary results.

Being able to perform a lost movement is an important experience towards increased independence and self-esteem, particularly for neuromuscular patients, who see their muscles weaken day after day. In this pilot study, preliminary results on the testing of a motorized upper-limb exoskeleton for muscular dystrophy patients are presented. The mechatronic system is a five Degrees of Freedom exoskeleton, which acts at shoulder, elbow, and wrist levels. It is designed to help severely impaired people to regain independence during daily-life activities. While wearing the exoskeleton, the user has the direct control of the system by actively piloting the position of end-effector by means of joystick or vocal control. The usability of the system and a quantitative assessment of arm functionality with and without the exoskeleton are evaluated on five muscular dystrophy patients. According to the objective functional benefit evaluation performed through the PUL scale, all participants strongly increased their range of motion and they were able to perform activities that were not possible without the exoskeleton, such as such as feeding, playing activities at the table, combing hair or using a keyboard. As for the evaluation of self-perceived functional benefit, four patients reflected the effective measured functional improvement. System usability has been evaluated to be good.

Quantitative Evaluation of Performance during Robot-assisted Treatment.

INTRODUCTION: This article is part of the Focus Theme of Methods of Information in Medicine on "Methodologies, Models and Algorithms for Patients Rehabilitation". OBJECTIVES: The great potential of robots in extracting quantitative and meaningful data is not always exploited in clinical practice. The aim of the present work is to describe a simple parameter to assess the performance of subjects during upper limb robotic training exploiting data automatically recorded by the robot, with no additional effort for patients and clinicians. METHODS: Fourteen children affected by cerebral palsy (CP) performed a training with Armeo®Spring. Each session was evaluated with P, a simple parameter that depends on the overall performance recorded, and median and interquartile values were computed to perform a group analysis. RESULTS: Median (interquartile) values of P significantly increased from 0.27 (0.21) at T0 to 0.55 (0.27) at T1 . This improvement was functionally validated by a significant increase of the Melbourne Assessment of Unilateral Upper Limb Function. CONCLUSIONS: The parameter described here was able to show variations in performance over time and enabled a quantitative evaluation of motion abilities in a way that is reliable with respect to a well-known clinical scale.

An ecological evaluation of the metabolic benefits due to robot-assisted gait training.

Cerebral palsy (CP), one of the most common neurological disorders in childhood, features affected individual's motor skills and muscle actions. This results in elevated heart rate and rate of oxygen uptake during sub-maximal exercise, thus indicating a mean energy expenditure higher than healthy subjects. Rehabilitation, currently involving also robot-based devices, may have an impact also on these aspects. In this study, an ecological setting has been proposed to evaluate the energy expenditure of 4 children with CP before and after a robot-assisted gait training. Even if the small sample size makes it difficult to give general indications, results presented here are promising. Indeed, children showed an increasing trend of the energy expenditure per minute and a decreasing trend of the energy expenditure per step, in accordance to the control group. These data suggest a metabolic benefit of the treatment that may increase the locomotion efficiency of disabled children.

Gait rehabilitation with a high tech platform based on virtual reality conveys improvements in walking ability of children suffering from acquired brain injury.

The Gait Real-time Analysis Interactive Lab (GRAIL) is an instrumented multi-sensor platform based on immersive virtual reality for gait training and rehabilitation. Few studies have been included GRAIL to evaluate gait patterns in normal and disabled people and to improve gait in adults, while at our knowledge no evidence on its use for the rehabilitation of children is available. In this study, 4 children suffering from acquired brain injury (ABI) underwent a 5 session treatment with GRAIL, to improve walking and balance ability in engaging VR environments. The first and the last sessions were partially dedicated to gait evaluation. Results are promising: improvements were recorded at the ankle level, selectively at the affected side, and at the pelvic level, while small changes were measured at the hip and knee joints, which were already comparable to healthy subjects. All these changes also conveyed advances in the symmetry of the walking pattern. In the next future, a longer intervention will be proposed and more children will be enrolled to strongly prove the effectiveness of GRAIL in the rehabilitation of children with ABI.

Further investigations on neurotensin as central modulator of intestinal motility in rats.

Previous studies have shown that neurotensin (NT) administered intracerebroventricularly (i.c.v.) to rats provokes an inhibition of intestinal propulsion linearly related to the log of administered doses. In the present study it is demonstrated that, in contrast to morphine, repeated i.c.v. administrations of NT (2.5 nmol/rat/day) did not result in tolerance to the intestinal effect. Naloxone (Nx) administered i.c.v. fully antagonized the intestinal inhibition of i.c.v. morphine, but did not significantly alter the NT effect. However, centrally administered thyrotropin-releasing hormone (TRH) inhibited NT-induced (but not morphine-induced) intestinal inhibition. Direct microinjections of NT into the periaqueductal gray matter (PAG) produced complete inhibition of intestinal propulsion when the microinjections were localized in the dorsal portion. Finally, subdiaphragmatic vagotomy totally abolished the inhibition induced by NT into the PAG, while morphine was not affected. Some considerations are put forward concerning the existence in the central nervous system of a peptidergic pathway modulating intestinal function.

Autotransfusion program: integrated use of different techniques.

A successful autologous program should enroll all appropriate patients, conserve homologous blood and minimise the exposure to the risks of donor blood. A program of autotransfusion and proper use of blood has been implemented since 1980 with the objectives to include all eligible patients and to transfuse autologous blood only. The following strategies were adopted: critical review of transfusion indications; control of overtransfusion; avoidance of waste; systematic and integrated use of all autotransfusion techniques currently available. Results in 1992 in elective surgery: 98% enrollment, 75% blood conservation. Exposure to homologous blood was completely avoided in 53% of the cases.

One-year use of the Bloodloc system in an orthopedic institute.

UNLABELLED: Human error in patient or specimen identification due to fatigue, stress and lack of attention by technologists, nurses, interns, and physicians, can cause routinely safety procedures to be circumvented. Clerical errors may occur during the specimen collection, the issue of blood unit and the transfusion of blood. The introduction in an increasing number of hospital of preoperative autologous blood donation programs further increases the chance of error, because a single patient can predeposit multiple units of blood. In this cases there is a greater commitment not only to transfuse any blood unit that is ABO compatible but to transfuse the specific units the patient previously donated for his own use. Human error has been recognized as a significant cause of transfusion-associated fatalities. The persistence of the frequency and type of errors observed in spite of extensive efforts to eradicate them, suggests that errors are inevitable as long as large number of repetitive procedures are performed unless major system changes are adopted. A system (Bloodloc System) that physically prevents the possibility of error was adopted since January 1993 and cuncurrently a quality improvement program (QI) was implemented specifically designed to monitor: 1. the absence of the code on the blood samples, 2. the blood bank error in setting the Bloodloc, 3. the misidentification of blood samples, 4. any attempt to transfuse the wrong blood unit, 5. any attempt to transfuse, the wrong patients. RESULTS: 4895 blood units (2469 autologous and 2426 allogeneic units) were transfused to 1478 patients (849 predeposited an average of 3.3 +/- 2.0 units). The methodological errors (absence of three-letter code on the patient's specimen tube, wrong transcription of the code on the blood sample, wrong setting of the Bloodloc in the blood bank)--41 cases--were limited at the first four months of implementation of the system. In the same period however have been reported 3 potentially fatal errors which have been avoided by the Bloodloc. Two cases of misidentification of blood samples at the moment of the specimen collection, and one attempt to transfuse the wrong units to the wrong patients. CONCLUSIONS: The Bloodloc system is effective in preventing potential transfusion-associated fatalities caused by units or recipients misidentification.

A new cross-correlation algorithm for the analysis of "in vitro" neuronal network activity aimed at pharmacological studies.

Modern drug discovery for Central Nervous System pathologies has recently focused its attention to in vitro neuronal networks as models for the study of neuronal activities. Micro Electrode Arrays (MEAs), a widely recognized tool for pharmacological investigations, enable the simultaneous study of the spiking activity of discrete regions of a neuronal culture, providing an insight into the dynamics of networks. Taking advantage of MEAs features and making the most of the cross-correlation analysis to assess internal parameters of a neuronal system, we provide an efficient method for the evaluation of comprehensive neuronal network activity. We developed an intra network burst correlation algorithm, we evaluated its sensitivity and we explored its potential use in pharmacological studies. Our results demonstrate the high sensitivity of this algorithm and the efficacy of this methodology in pharmacological dose-response studies, with the advantage of analyzing the effect of drugs on the comprehensive correlative properties of integrated neuronal networks.

Development and validation of a spike detection and classification algorithm aimed at implementation on hardware devices.

Neurons cultured in vitro on MicroElectrode Array (MEA) devices connect to each other, forming a network. To study electrophysiological activity and long term plasticity effects, long period recording and spike sorter methods are needed. Therefore, on-line and real time analysis, optimization of memory use and data transmission rate improvement become necessary. We developed an algorithm for amplitude-threshold spikes detection, whose performances were verified with (a) statistical analysis on both simulated and real signal and (b) Big O Notation. Moreover, we developed a PCA-hierarchical classifier, evaluated on simulated and real signal. Finally we proposed a spike detection hardware design on FPGA, whose feasibility was verified in terms of CLBs number, memory occupation and temporal requirements; once realized, it will be able to execute on-line detection and real time waveform analysis, reducing data storage problems.

[A new echocardiographic detection technique of the pulmonary valve (VP) in patients with cor pulmonale chronicum (CPC) (author's transl)]. / Nuova tecnica di esplorazione ecocardiografica della valvola polmonare nei portatori di cuore polmonare cronico

In this paper, a new echocardiographic detection technique of the VP in patients with CPC is described. Subjects who frequently have large, barrel chests, with pulmonary emphysema and markedly depressed diaphragms, are very difficult to examine echocardiographically. By this technique, however, the authors obtained the highest detection rate so far reported (congruent to 100% of the patients studied). Moreover, the echocardiographic findings are validated by an ultrasonic anatomy study based on the use of Cardio Green (V.I.) as contrast agent.

The potential role of oxygen-carrying products in autologous blood transfusion protocols.

For surgical patients transfusion of autologous blood (AB) is the most useful of measures to reduce patient's exposure to homologous blood (HB). In our Institute an autotransfusion program was started in 1982 utilizing all the autotransfusion techniques currently available. The integrated use of the techniques offered to the majority of the patients the possibility of receiving AB (98% of the elective surgery patients) and a consistent conservation of HB has been achieved (60-70%). However 42% are still exposed to some HB. Critical parameters that render the patients unable to fulfill the anticipated transfusion needs with the current AB transfusion techniques are: the patient's ability to predonate sufficient AB prior to surgery and the amount of blood transfused intraoperatively that in turn depends on different "transfusion trigger". In our Institute over 50% of all the blood units are transfused the day of operation (60% being AB, 40% HB) and 50% postoperatively (only 33% being AB). For this reason, a clinical application for the oxygen-carrying products can be the replacement of the blood lost during, or immediately after the operation permitting the surgeon to operate safely at a lower Hct levels, thereby delaying the transfusion of blood and saving the AB obtained.

Epoetin alfa in low hematocrit patients to facilitate autologous blood donation in total hip replacement: a randomized, double-blind, placebo-controlled, dose-ranging study.

We investigated the safety and efficacy of preoperative epoetin alfa used in conjunction with preoperative autologous blood donation (PAD) in 40 anemic orthopedic surgical patients undergoing hip replacement surgery [hematocrit (Hct)

Autologous blood pre-deposit and cell salvage in orthopedic surgery.

A successful autologous blood program should enrol all appropriate patients, conserve homologous blood and minimize the exposure to the risks of donor blood. A program of autotransfusion and proper use of blood has been implemented since 1980 with the objectives of including all eligible patients and to transfuse autologous blood only. The following strategies were adopted: critical review of transfusion indications; control of over-transfusion; avoidance of waste; systematic and integrated use of all autotransfusion techniques currently available. Results in 1992 in elective surgery: 98% enrolment, 75% blood conservation. Exposure to homologous blood was completely avoided in 53% of the cases.

M-mode subxiphoid echocardiography in assessing pulmonary hypertension. Its usefulness in chronic obstructive pulmonary disease.

12 patients (9 males, 3 females; aged 35-63 years, mean 55) with chronic obstructive pulmonary disease (COPD) were studied in order to determine the correlation between the values of pulmonary arterial pressure and the M-mode echographic size of the right pulmonary artery (RPA) from the subxiphoid approach. Both the largest (systolic) and smallest (diastolic) size of the vessel were considered, and both were corrected for body surface area ('index size' - PA/BSA). The reliability of this echographic size is supported by the evidence that the tract of the pulmonary artery considered in this study is perpendicular to the ultrasonic beam. Both the systolic and diastolic size of RPA correlated with the systolic, diastolic, and mean pulmonary arterial pressure, detected by catheterization. Measurements of RPA size were made from the suprasternal approach in 8 patients out of 12. The size of RPA from the subxiphoid approach was also estimated in 21 normal subjects, serving as controls. Measurements of RPA size from the suprasternal approach were made in 12 of these subjects. Both the systolic and diastolic size of RPA from the subxiphoid approach correlated with the systolic and diastolic size of the suprasternal view in patients and in normal subjects. Subxiphoid M-mode echocardiography seems to be a valuable noninvasive technique in assessment of pulmonary hypertension, particularly in patients affected by COPD.

Use of erythropoietin to increase the volume of autologous blood donated by orthopedic patients.

For patients who donate blood for autologous use and undergo major orthopedic surgery, low basal hematocrit (Hct) is the major cause of allogeneic blood exposure. To determine whether recombinant human erythropoietin (rHuEPO) could increase autologous blood procurement and reduce allogeneic blood exposure, a prospective randomized study was conducted in 50 women undergoing total hip replacement who had basal Hct < 40 percent (0.40). Patients were randomly placed in three groups: those receiving placebo, those receiving 300 U of rHuEPO per kg, and those receiving 600 U of rHuEPO per kg every 3 to 4 days for 21 days. Oral iron (125-270 mg/day) was given; in the last 24 patients, 100 mg of iron saccharate was administered intravenously at each donation. At each visit, 350 mL of blood was collected if Hct was > or = 34 percent (0.34). Patients receiving rHuEPO donated a greater amount of blood for autologous use than did patients in the placebo group (4.5 +/- 1.1 vs. 2.8 +/- 0.6 units; p < 0.05) and received a significantly lower amount of allogeneic blood (1.2 +/- 1.4 vs. 0.4 +/- 0.8 units; p < 0.05). No difference between the effects of the two doses of rHuEPO was observed. Iron support was a critical factor in the efficacy of treatment. No untoward effects were observed. The rHuEPO emerged as a safe and effective treatment, with adequate iron support, by which to increase preoperative deposit of autologous blood and to reduce exposure to allogeneic blood for patients with low basal Hct.