Photonic artificial muscles: From micro robots to tissue engineering

Light responsive shape-changing polymers are able to mimic the function of biological muscles accomplishing mechanical work in response to selected stimuli. A variety of manufacturing techniques and chemical processes can be employed to shape these materials to different length scales, from centimeter fibers and films to 3D printed micrometric objects trying to replicate biological functions and operations. Controlled deformations shown to mimick basic animal operations such as walking, swimming or grabbing objects, while also controlling the refractive index and the geometry of devices, opens up the potential to implement tunable optical properties. Another possibility is that of combining artificial polymers with cells or biological tissue (such as intact cardiac trabeculae) with the aim to improve tissue formation in vitro or to support the mechanical function of damaged biological muscles. Such versatility is afforded by chemistry. New customized liquid crystalline monomers are presented here that modulate material properties for different applications. The role of synthetic material composition is highlighted as we demonstrate how using apparently similar molecular formulations, that liquid crystalline polymers can be adapted to different technological and medical challenges

Free-form Light Actuators - Fabrication and Control of Actuation in Microscopic Scale

Liquid crystalline elastomers (LCEs) are smart materials capable of reversible shape-change in response to external stimuli, and have attracted researchers' attention in many fields. Most of the studies focused on macroscopic LCE structures (films, fibers) and their miniaturization is still in its infancy. Recently developed lithography techniques, e.g., mask exposure and replica molding, only allow for creating 2D structures on LCE thin films. Direct laser writing (DLW) opens access to truly 3D fabrication in the microscopic scale. However, controlling the actuation topology and dynamics at the same length scale remains a challenge. In this paper we report on a method to control the liquid crystal (LC) molecular alignment in the LCE microstructures of arbitrary three-dimensional shape. This was made possible by a combination of direct laser writing for both the LCE structures as well as for micrograting patterns inducing local LC alignment. Several types of grating patterns were used to introduce different LC alignments, which can be subsequently patterned into the LCE structures. This protocol allows one to obtain LCE microstructures with engineered alignments able to perform multiple opto-mechanical actuation, thus being capable of multiple functionalities. Applications can be foreseen in the fields of tunable photonics, micro-robotics, lab-on-chip technology and others

Correlations of Globular Cluster Properties: Their Interpretations and Uses

Correlations among the independently measured physical properties of globular clusters (GCs) can provide powerful tests for theoretical models and new insights into their dynamics, formation, and evolution. We review briefly some of the previous work, and present preliminary results from a comparative study of GC correlations in the Local Group galaxies. The results so far indicate that these diverse GC systems follow the same fundamental correlations, suggesting a commonality of formative and evolutionary processes which produce them.Comment: An invited review, to appear in "New Horizons in Globular Cluster Astronomy", eds. G. Piotto, G. Meylan, S.G. Djorgovski, and M. Riello, ASPCS, in press (2003). Latex file, 8 pages, 5 eps figures, style files include

Laparoscopic approach to Meckel's diverticulum

Aim.To retrospective review the laparoscopic management of Meckel Diverticulum (MD) in two Italian Pediatric Surgery Centers. METHODS: Between January 2002 and December 2012, 19 trans-umbilical laparoscopic-assisted (TULA) procedures were performed for suspected MD. The children were hospitalized for gastrointestinal bleeding and/or recurrent abdominal pain. Median age at diagnosis was 5.4 years (range 6 mo-15 years). The study included 15 boys and 4 girls. All patients underwent clinical examination, routine laboratory tests, abdominal ultrasound and technetium-99m pertechnetate scan, and patients with bleeding underwent gastrointestinal endoscopy. The abdominal exploration was performed with a 10 mm operative laparoscope. Pneumoperitoneum was established based on the body weight. Systematic overview of the peritoneal cavity allowed the ileum to be grasped with an atraumatic instrument. The complete exploration and surgical treatment of MD were performed extracorporeally, after intestinal exteriorization through the umbilicus. All patients' demographics, main clinical features, diagnostic investigations, operative time, histopathology reports, conversion rate, hospital stay and complications were registered and analyzed. RESULTS: MD was identified in 17 patients, while 1 had an ileal duplication and 1 a jejunal hemangioma. Fifteen patients had painless intestinal bleeding, while 4 had recurrent abdominal pain and exhibited cyst like structures in an ultrasound study. Eleven patients had a positive technetium-99m pertechnetate scan. In the patients with bleeding, gastrointestinal endoscopy did not name the source of hemorrhage. All patients were subjected to a TULA surgical procedure. An intestinal resection/anastomosis was performed in 14 patients, while 4 had a wedge resection of the diverticulum and 1 underwent stapling diverticulectomy. All surgical procedures were performed without conversion to open laparotomy. Mean operative time was 75 min (range 40-115 min). No major surgical complications were recorded. The median hospital stay was 5-7 d (range 4-13 d). All patients are asymptomatic at a median follow up of 4, 5 years (range 10 mo-10 years). CONCLUSION: Trans-umbilical laparoscopic-assisted Meckel's diverticulectomy is safe and effective in the treatment of MD, with excellent results. KEYWORDS: Gastrointestinal bleeding; Ileal duplication; Jejunal hemangioma; Laparoscopy; Meckel’s diverticulum; Minimal invasive surgery; One trocar surger

SUNCT/SUNA in pediatric age: A review of pathophysiology and therapeutic options

The International Classification of Headache Disorders, 3rd edition (ICHD3) defines Short-lasting Unilateral Neuralgiform Headache Attacks (SUNHA) as attacks of moderate or severe, strictly unilateral head pain lasting from seconds to minutes, occurring at least once a day and usually associated with prominent lacrimation and redness of the ipsilateral eye. Two subtypes of SUNHA are identified: Short-lasting Unilateral Neuralgiform headache attacks with Conjunctival injection and Tearing (SUNCT) and Short-lasting Unilateral Neuralgiform headache attacks with cranial Autonomic symptoms (SUNA). These pathologies are infrequent in children and difficult to diagnose. The authors reviewed the existing literature on SUNCT and SUNA, especially in the developmental age, which describes the pathophysiology in detail and focuses on the therapeutic options available to date. SUNHA-type headaches must be considered on the one hand, for the possibility of the onset of forms secondary to underlying pathologies even of a neoplastic nature, and on the other hand, for the negative impact they can have on an individual’s quality of life, particularly in young patients. Until now, published cases suggest that no chronic variants occur in childhood and adolescents. In light of this evidence, the authors offer a review that may serve as a source to be drawn upon in the implementation of suitable treatments in children and adolescents suffering from these headaches, focusing on therapies that are non-invasive and as risk-free as possible for pediatric patients

Photoresponsive Polymer-Based Biomimetic Contractile Units as Building Block for Artificial Muscles

Loss of muscular mechanical function occurs in several diseases affecting millions of people worldwide, including heart failure, stroke, and neuromuscular disorders. To date, no medical or surgical treatments can restore muscular contractility, and the development of artificial muscles is of extreme interest. Mimicking biological muscles, which are optimized systems displaying quick reaction times, is not trivial; only few examples are reported, mainly focused on the use of biomimetic smart materials. Among them, liquid crystalline elastomers (LCEs) can be biocompatible, show contraction parameters comparable to those of native striated muscles, and are able to effectively potentiate cardiac contraction in vitro. To go further and develop in vivo implantable devices, the integration of the stimulation system with the LCE material represents an essential step. Here, a light-stimulated biomimetic contractile unit (BCU), combining ultra-thin photoresponsive LCE films and mini-LED (mLED) matrixes is described. BCU performance (in terms of extent and kinetics of contractile force and shortening) can be fine-tuned by modulating both mLED light power and spatial stimulation patterns, allowing to reproduce mechanical dynamics of native muscles. These results pave the way for the development of novel LCE-based contraction assist devices for cardiac, skeletal, or smooth muscle support by assembling multiple BCUs

Quality improvement of medical records in a teaching hospital

Introduction. The aim of this study was to evaluate the quality of the MR compilation in some Operative Units of the ?Azienda Ospedaliera Universitaria - II Università di Napoli? (AOU- SUN) - Italy, before and after an intervention of quality improve- ment, underlining the potential differences in the behaviour of dif- ferent specialists (physicians vs. surgeons). Methods. Two random samples of 660 MRs were reviewed. A four-step program was developed: 1) first assessment of the MR; 2) implementation of the MR quality, sending a letter with the purpose of the study, the results obtained in the first step from that ward, the guidelines to correctly fill out the MR; 3) follow-up step four months later; 4) comparison of the data before and after the distribution of the guidelines using indicators of completeness of all sections of MR, clarity of handwriting and presence and clar- ity of signature. Results. The main concerns were related to the signature of the duty physician (present in 2.0% and legible in only 15.4%), the presence of the letter of discharge (18.0%) and the clarity of the days of hospital stay (32.0%). After the intervention the improvement of the quality of compilation was modest and regarded mainly medical rather than surgical wards. Discussion and conclusions. The improvement was not satisfying since from a medical and a legal point of view the indicators should reach 100% of clarity and completeness. A further study is being carried out to improve the involvement of health care professional, so that such requirements will be perceived as a common goal, not as mere bureaucratic initiatives

Adjunctive clotiapine for the management of delusions in two adolescents with anorexia nervosa

Clotiapine is an atypical antipsychotic indicated for the management of a series of acute psychotic disorders. The current literature lacks evidence concerning the tolerability and clinical use of this drug in the management of individuals with anorexia nervosa (AN). In this study, we report two cases of adolescents with AN, treated with clotiapine. The reason for the administration of clotiapine was, for both patients, the manifestation of bizarre delusions concerning food and calories. Patient 1 presented a presyncope after the first dose of clotiapine, and treatment was rapidly discontinued. Patient 2 was treated with clotiapine for 9 months; doses were titrated from 20 mg/day to 70 mg/day, with an improvement in the reported delusions, which also enhanced compliance with psychological and nutritional interventions. EKG, QTc, white blood count, and red blood count were not relevantly influenced by the introduction of clotiapine in either patient. No extrapyramidal effect was documented. These reports stress the need for further studies assessing the tolerability and potential effect of clotiapine in treating adolescents with AN and delusional symptomatology