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2.
Sensors (Basel) ; 23(7)2023 Mar 29.
Article in English | MEDLINE | ID: mdl-37050629

ABSTRACT

In the highly competitive injection molding industry, the ability to effectively collect information from various sensors installed in molds and machines is of the utmost relevance, enabling the development of data-based Industry 4.0 algorithms. In this work, an alternative to commercially available monitoring systems used in the industry was developed and tested in the scope of the TOOLING 4G project. The novelty of this system is its affordability, simplicity, real-time data acquisition and display in an intuitive Graphical User Interface (GUI), while being open-source firmware and software-based. These characteristics, and their combinations have been present in previous works, but, to the authors' knowledge, not all of them simultaneously. The system used an Arduino microcontroller-based data acquisition module that can be connected to any computer via a USB port. Software was developed, including a GUI, prepared to receive data from both the Arduino module and a second module. In the current state of development, data corresponding to a maximum of six sensors can be visualized, at a rate of 10 Hz, and recorded for later usage. These capabilities were verified under real-world conditions for monitoring an injection mold with the objective of creating the basis of a platform to deploy predictive maintenance. Mold temperature, cavity pressure, 3-axis acceleration, and extraction force data showed the system can successfully monitor the mold and allowed the clear distinction between normal and abnormal operating patterns.

3.
Sensors (Basel) ; 22(7)2022 Mar 25.
Article in English | MEDLINE | ID: mdl-35408143

ABSTRACT

The world population growth and average life expectancy rise have increased the number of people suffering from non-communicable diseases, namely osteoarthritis, a disorder that causes a significant increase in the years lived with disability. Many people who suffer from osteoarthritis undergo replacement surgery. Despite the relatively high success rate, around 10% of patients require revision surgeries, mostly because existing implant technologies lack sensing devices capable of monitoring the bone-implant interface. Among the several monitoring methodologies already proposed as substitutes for traditional imaging methods, cosurface capacitive sensing systems hold the potential to monitor the bone-implant fixation states, a mandatory capability for long-term implant survival. A multifaceted study is offered here, which covers research on the following points: (1) the ability of a cosurface capacitor network to effectively monitor bone loosening in extended peri-implant regions and according to different stimulation frequencies; (2) the ability of these capacitive architectures to provide effective sensing in interfaces with hydroxyapatite-based layers; (3) the ability to control the operation of cosurface capacitive networks using extracorporeal informatic systems. In vitro tests were performed using a web-based network sensor composed of striped and interdigitated capacitive sensors. Hydroxyapatite-based layers have a minor effect on determining the fixation states; the effective operation of a sensor network-based solution communicating through a web server hosted on Raspberry Pi was shown. Previous studies highlight the inability of current bone-implant fixation monitoring methods to significantly reduce the number of revision surgeries, as well as promising results of capacitive sensing systems to monitor micro-scale and macro-scale bone-interface states. In this study, we found that extracorporeal informatic systems enable continuous patient monitoring using cosurface capacitive networks with or without hydroxyapatite-based layers. Findings presented here represent significant advancements toward the design of future multifunctional smart implants.


Subject(s)
Durapatite , Osteoarthritis , Bone Transplantation/methods , Humans , Prostheses and Implants , Reoperation/methods
4.
NPJ Regen Med ; 6(1): 80, 2021 Nov 23.
Article in English | MEDLINE | ID: mdl-34815414

ABSTRACT

Replacement orthopedic surgeries are among the most common surgeries worldwide, but clinically used passive implants cannot prevent failure rates and inherent revision arthroplasties. Optimized non-instrumented implants, resorting to preclinically tested bioactive coatings, improve initial osseointegration but lack long-term personalized actuation on the bone-implant interface. Novel bioelectronic devices comprising biophysical stimulators and sensing systems are thus emerging, aiming for long-term control of peri-implant bone growth through biointerface monitoring. These acting-sensing dual systems require high frequency (HF) operations able to stimulate osteoinduction/osteoconduction, including matrix maturation and mineralization. A sensing-compatible capacitive stimulator of thin interdigitated electrodes and delivering an electrical 60 kHz HF stimulation, 30 min/day, is here shown to promote osteoconduction in pre-osteoblasts and osteoinduction in human adipose-derived mesenchymal stem cells (hASCs). HF stimulation through this capacitive interdigitated system had significant effects on osteoblasts' collagen-I synthesis, matrix, and mineral deposition. A proteomic analysis of microvesicles released from electrically-stimulated osteoblasts revealed regulation of osteodifferentiation and mineralization-related proteins (e.g. Tgfb3, Ttyh3, Itih1, Aldh1a1). Proteomics data are available via ProteomeXchange with the identifier PXD028551. Further, under HF stimulation, hASCs exhibited higher osteogenic commitment and enhanced hydroxyapatite deposition. These promising osteoinductive/conductive capacitive stimulators will integrate novel bioelectronic implants able to monitor the bone-implant interface and deliver personalized stimulation to peri-implant tissues.

5.
Sci Rep ; 11(1): 3449, 2021 02 10.
Article in English | MEDLINE | ID: mdl-33568680

ABSTRACT

Instrumented implants are being developed with a radically innovative design to significantly reduce revision surgeries. Although bone replacements are among the most prevalent surgeries performed worldwide, implant failure rate usually surpasses 10%. High sophisticated multifunctional bioelectronic implants are being researched to incorporate cosurface capacitive architectures with ability to deliver personalized electric stimuli to peri-implant target tissues. However, the ability of these architectures to detect bone-implant interface states has never been explored. Moreover, although more than forty technologies were already proposed to detect implant loosening, none is able to ensure effective monitoring of the bone-implant debonding, mainly during the early stages of loosening. This work shows, for the first time, that cosurface capacitive sensors are a promising technology to provide an effective monitoring of bone-implant interfaces during the daily living of patients. Indeed, in vitro experimental tests and simulation with computational models highlight that both striped and circular capacitive architectures are able to detect micro-scale and macro-scale interface bonding, debonding or loosening, mainly when bonding is weakening or loosening is occurring. The proposed cosurface technologies hold potential to implement highly effective and personalized sensing systems such that the performance of multifunctional bioelectronic implants can be strongly improved. Findings were reported open a new research line on sensing technologies for bioelectronic implants, which may conduct to great impacts in the coming years.

6.
J Pediatr Hematol Oncol ; 43(3): 79-89, 2021 04 01.
Article in English | MEDLINE | ID: mdl-32925406

ABSTRACT

Central nervous system tumors comprise 26% of cancer in children, representing the most frequent solid neoplasms. Embryonal tumors comprise 15% of them, and they are defined as "small round blue cells" in which morphology is reminiscent of the developing embryonic nervous system. They are the most common high-grade central nervous system neoplasms. Over the years, molecular research has been improving our knowledge concerning these neoplasms, stressing the need for tumor reclassification. Indeed, the revised 2016 fourth edition of the World Health Organization classification introduced genetic parameters in the classification. Specific molecular signatures allow a more accurate risk assessment, leading to proper therapeutic approach and potentially improved prognosis. Holding this new approach, medulloblastoma is noteworthy. The present classification combines the previous histologic classification with a new genetic definition in WNT-activated, sonic hedgehog-activated and non-WNT/non-sonic hedgehog. Molecular data are also a defining feature in the diagnosis of atypical teratoid/rhabdoid tumors and embryonal tumors with multilayered rosettes. However, there are still embryonal tumors that challenge the present World Health Organization classification, and new molecular data have been underlining the need for novel tumor entities. Likewise, recent research has been highlighting heterogeneity in recognized entities. How to translate these molecular developments into routine clinical practice is still a major challenge.


Subject(s)
Central Nervous System Neoplasms/classification , Neoplasms, Germ Cell and Embryonal/classification , Central Nervous System Neoplasms/genetics , Central Nervous System Neoplasms/pathology , Child , Chromosomes, Human, Pair 19 , Genetic Predisposition to Disease , Humans , MicroRNAs/genetics , Mutation , Neoplasms, Germ Cell and Embryonal/genetics , Neoplasms, Germ Cell and Embryonal/pathology , World Health Organization
7.
Sensors (Basel) ; 20(1)2019 Dec 23.
Article in English | MEDLINE | ID: mdl-31878028

ABSTRACT

Musculoskeletal disorders are becoming an ever-growing societal burden and, as a result, millions of bone replacements surgeries are performed per year worldwide. Despite total joint replacements being recognized among the most successful surgeries of the last century, implant failure rates exceeding 10% are still reported. These numbers highlight the necessity of technologies to provide an accurate monitoring of the bone-implant interface state. This study provides a detailed review of the most relevant methodologies and technologies already proposed to monitor the loosening states of endoprosthetic implants, as well as their performance and experimental validation. A total of forty-two papers describing both intracorporeal and extracorporeal technologies for cemented or cementless fixation were thoroughly analyzed. Thirty-eight technologies were identified, which are categorized into five methodologies: vibrometric, acoustic, bioelectric impedance, magnetic induction, and strain. Research efforts were mainly focused on vibrometric and acoustic technologies. Differently, approaches based on bioelectric impedance, magnetic induction and strain have been less explored. Although most technologies are noninvasive and are able to monitor different loosening stages of endoprosthetic implants, they are not able to provide effective monitoring during daily living of patients.


Subject(s)
Bone Transplantation/methods , Prosthesis Failure , Humans , Magnetics , Sound , Vibration
8.
Sci Rep ; 9(1): 5001, 2019 03 21.
Article in English | MEDLINE | ID: mdl-30899061

ABSTRACT

Cosurface electrode architectures are able to deliver personalized electric stimuli to target tissues. As such, this technology holds potential for a variety of innovative biomedical devices. However, to date, no detailed analyses have been conducted to evaluate the impact of stimulator architecture and geometry on stimuli features. This work characterizes, for the first time, the electric stimuli delivered to bone cellular tissues during in vitro experiments, when using three capacitive architectures: stripped, interdigitated and circular patterns. Computational models are presented that predict the influence of cell confluence, cosurface architecture, electrodes geometry, gap size between electrodes and power excitation on the stimuli delivered to cellular layers. The results demonstrate that these stimulators are able to deliver osteoconductive stimuli. Significant differences in stimuli distributions were observed for different stimulator designs and different external excitations. The thickness specification was found to be of utmost importance. In vitro experiments using an osteoblastic cell line highlight that cosurface stimulation at a low frequency can enhance osteoconductive responses, with some electrode-specific differences being found. A major feature of this type of work is that it enables future detailed analyses of stimuli distribution throughout more complex biological structures, such as tissues and organs, towards sophisticated biodevice personalization.


Subject(s)
Computer Simulation , Electric Stimulation/instrumentation , Prostheses and Implants , Electrodes , Humans , Precision Medicine
9.
Nanoscale ; 10(15): 7238-7249, 2018 Apr 19.
Article in English | MEDLINE | ID: mdl-29632908

ABSTRACT

Fluoropyrimidines, such as 5-fluorouracil (5-FU) and related prodrugs, are considered one of the most successful agents in the treatment of colorectal cancer, yet poor specificity and tumor cell resistance remain the major limiting bottlenecks. Here, we exploited for the first time the ability of two DNA nanoscaffolds, a DNA tetrahedron (Td) and rectangle DNA origami, to incorporate 5-fluoro-2'-deoxyuridine (FdUn) oligomers. In addition, cholesterol moieties were synthetically attached to Td and DNA origami staples to enhance cellular uptake. DNA nanostructures functionalized with FdUn exhibited an enhanced cytotoxicity and higher ability to trigger apoptosis in colorectal cancer cells relative to conventional 5-FU and FdU, especially having cholesterol as an internalization helper. The cholesterol content mostly correlates with the increase of the FdUn nanostructure cytotoxicity. DNA nanoscaffolds bearing FdUn were able to circumvent the low sensitivity of colorectal cancer cells towards 5-FU. Both DNA nanostructures attained a comparable cytotoxic effect yet Td displays higher antiproliferative action. The ability to reduce the proliferation of cancer cells is mainly related to the concentration of DNA nanostructures. The present work suggests that self-assembled DNA nanoparticles are privileged vehicles for delivering fluoropyrimidines, opening new avenues to the development of promising therapeutics for cancer treatment.


Subject(s)
Cholesterol/chemistry , Colorectal Neoplasms/drug therapy , DNA/chemistry , Deoxyuridine/analogs & derivatives , Nanostructures , Cell Line, Tumor , Deoxyuridine/pharmacology , Drug Resistance, Neoplasm , Fluorouracil , Humans
10.
Sci Rep ; 6: 30231, 2016 07 26.
Article in English | MEDLINE | ID: mdl-27456818

ABSTRACT

Non-drug strategies based on biophysical stimulation have been emphasized for the treatment and prevention of musculoskeletal conditions. However, to date, an effective stimulation system for intracorporeal therapies has not been proposed. This is particularly true for active intramedullary implants that aim to optimize osseointegration. The increasing demand for these implants, particularly for hip and knee replacements, has driven the design of innovative stimulation systems that are effective in bone-implant integration. In this paper, a new cosurface-based capacitive system concept is proposed for the design of implantable devices that deliver controllable and personalized electric field stimuli to target tissues. A prototype architecture of this system was constructed for in vitro tests, and its ability to deliver controllable stimuli was numerically analyzed. Successful results were obtained for osteoblastic proliferation and differentiation in the in vitro tests. This work provides, for the first time, a design of a stimulation system that can be embedded in active implantable devices for controllable bone-implant integration and regeneration. The proposed cosurface design holds potential for the implementation of novel and innovative personalized stimulatory therapies based on the delivery of electric fields to bone cells.


Subject(s)
Bone Development/physiology , Fracture Fixation, Intramedullary/methods , Osseointegration/radiation effects , Prostheses and Implants , Bone Development/radiation effects , Cell Differentiation/radiation effects , Cell Proliferation/radiation effects , Electric Stimulation , Humans , Osseointegration/physiology , Surface Properties
11.
Sci Rep ; 6: 18579, 2016 Jan 04.
Article in English | MEDLINE | ID: mdl-26725842

ABSTRACT

Magnetic levitation has been used to implement low-cost and maintenance-free electromagnetic energy harvesting. The ability of levitation-based harvesting systems to operate autonomously for long periods of time makes them well-suited for self-powering a broad range of technologies. In this paper, a combined theoretical and experimental study is presented of a harvester configuration that utilizes the motion of a levitated hard-magnetic element to generate electrical power. A semi-analytical, non-linear model is introduced that enables accurate and efficient analysis of energy transduction. The model predicts the transient and steady-state response of the harvester a function of its motion (amplitude and frequency) and load impedance. Very good agreement is obtained between simulation and experiment with energy errors lower than 14.15% (mean absolute percentage error of 6.02%) and cross-correlations higher than 86%. The model provides unique insight into fundamental mechanisms of energy transduction and enables the geometric optimization of harvesters prior to fabrication and the rational design of intelligent energy harvesters.

12.
Expert Rev Med Devices ; 12(5): 571-84, 2015.
Article in English | MEDLINE | ID: mdl-26202322

ABSTRACT

This article focuses on in vivo implementations of instrumented knee implants and recent prototypes with highly innovative potential. An in-depth analysis of the evolution of these systems was conducted, including three architectures developed by two research teams for in vivo operation that were implanted in 13 patients. The specifications of their various subsystems: sensor/transducers, power management, communication and processing/control units are presented, and their features are compared. These systems were designed to measure biomechanical quantities to further assist in rehabilitation and physical therapy, to access proper implant placement and joint function and to help predicting aseptic loosening. Five prototype systems that aim to improve their operation, as well as include new abilities, are also featured. They include technology to assist proper ligament tensioning and ensure self-powering. One can conclude that the concept of instrumented active knee implant seems the most promising trend for improving the outcomes of knee replacements.


Subject(s)
Knee Joint/surgery , Knee Prosthesis , Biomechanical Phenomena , Humans , Knee Joint/physiopathology , Ligaments/physiopathology
13.
PLoS One ; 10(6): e0129145, 2015.
Article in English | MEDLINE | ID: mdl-26053858

ABSTRACT

Current study evaluated the effect of pre-slaughter stress on serum cortisol levels, pH, colorimetry, water-holding capacity (WHC) and gene expression of ryanodine receptors (RyR1 and RyR3) in the Nile tilapia. A 3x4 factorial scheme experiment was conducted comprising three densities (100, 200, 400 kg/m³) with four transportation times (60, 120, 180, and 240 minutes).Transportation times alone reduced cortisol levels up to 180 minutes, followed by increased WHC and mRNA expression, RyR1 and RyR3 (200 kg/m³ density). No effect of density x transportation time interacted on the evaluated parameters. Results provided the first evidence that pre-slaughter stress affected ryanodine gene expression receptors and, consequently, the water-holding capacity in tilapia fillets.


Subject(s)
Cichlids/physiology , Gene Expression , Ryanodine Receptor Calcium Release Channel/genetics , Stress, Physiological , Animals , Hydrocortisone/metabolism , Phenotype
14.
Expert Rev Med Devices ; 11(6): 617-35, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25234709

ABSTRACT

This paper reviews instrumented hip joint replacements, instrumented femoral replacements and instrumented femoral fracture stabilizers. Examination of the evolution of such implants was carried out, including the detailed analysis of 16 architectures, designed by 8 research teams and implanted in 32 patients. Their power supply, measurement, communication, processing and actuation systems were reviewed, as were the tests carried out to evaluate their performance and safety. These instrumented implants were only designed to measure biomechanical and thermodynamic quantities in vivo, in order to use such data to conduct research projects and optimize rehabilitation processes. The most promising trend is to minimize aseptic loosening and/or infection following hip or femoral replacements or femoral stabilization procedures by using therapeutic actuators inside instrumented implants to apply controlled stimuli in the bone-implant interface.


Subject(s)
Femoral Fractures/diagnosis , Femoral Fractures/surgery , Femur/surgery , Hip Prosthesis , Internal Fixators , Monitoring, Ambulatory/instrumentation , Wireless Technology/instrumentation , Electronics, Medical/instrumentation , Equipment Design , Equipment Failure Analysis , Humans , Technology Assessment, Biomedical
15.
J Biomech ; 46(15): 2561-71, 2013 Oct 18.
Article in English | MEDLINE | ID: mdl-24050511

ABSTRACT

Instrumented hip implants were proposed as a method to monitor and predict the biomechanical and thermal environment surrounding such implants. Nowadays, they are being developed as active implants with the ability to prevent failures by loosening. The generation of electric energy to power active mechanisms of instrumented hip implants remains a question. Instrumented implants cannot be implemented without effective electric power systems. This paper surveys the power supply systems of seventeen implant architectures already implanted in-vivo, namely from instrumented hip joint replacements and instrumented fracture stabilizers. Only inductive power links and batteries were used in-vivo to power the implants. The energy harvesting systems, which were already designed to power instrumented hip implants, were also analyzed focusing their potential to overcome the disadvantages of both inductive-based and battery-based power supply systems. From comparative and critical analyses of the methods to power instrumented implants, one can conclude that: inductive powering and batteries constrain the full operation of instrumented implants; motion-driven electromagnetic energy harvesting is a promising method to power instrumented passive and active hip implants.


Subject(s)
Electric Power Supplies , Hip Prosthesis , Humans , Prosthesis Failure
16.
Gynecol Obstet Fertil ; 40(4): 213-8, 2012 Apr.
Article in French | MEDLINE | ID: mdl-22153154

ABSTRACT

OBJECTIVES: The availability of information on HPV and Pap tests has increased dramatically with the introduction of national HPV vaccination programs. But data on the effectiveness of this information is limited. However, our desire is to reduce patient anxiety and promote better delivery of information. PATIENTS AND METHODS: Therefore a questionnaire-based cohort study was conducted to investigate women's experience with the announcement of an abnormal Pap smear result, then the ensuing events, as well as their practitioner's management. This article focuses on the French experience, underpinned by comparative data with Spain and Portugal. RESULTS: It shows that, face with stress reactions and patient's anxiety, the level of information from the medical profession is still seen as inadequate, while the Internet as an information source has its limitations and dangers. The close entourage is most relied on, which supports the need for better public information. DISCUSSION AND CONCLUSION: Uniformity and standardization of information strategies is not yet on European time.


Subject(s)
Papanicolaou Test , Perception , Vaginal Smears/psychology , Adult , Anxiety , Cohort Studies , Consumer Health Information , Female , France , Humans , Middle Aged , Papillomavirus Infections/diagnosis , Papillomavirus Infections/psychology , Patient Education as Topic , Portugal , Spain , Surveys and Questionnaires , Uterine Cervical Neoplasms/diagnosis , Uterine Cervical Neoplasms/psychology
17.
Eur J Gynaecol Oncol ; 32(4): 448-51, 2011.
Article in English | MEDLINE | ID: mdl-21941976

ABSTRACT

INTRODUCTION: Malignant melanoma (MM) represents 1% of all cancers and has an incidence of 3-7% in the female genital tract, the majority of cases being reported in the vulva and vagina. CASE REPORT: A 75-year-old white female had a history of vaginal bleeding due to a 1.5 cm exophytic and ulcerated cervical lesion. Incisional biopsy was taken and sent for histopathological examination, which revealed MM of the cervix, confirmed by immunohistochemistry. Exclusion of the primitive tumor in other sites was made and after FIGO staging (IB1) the patient underwent a radical hysterectomy with bilateral salpingo-oophorectomy and pelvic lymphadenectomy. Three months later, hepatic and osseous metastases were detected, and the patient underwent chemotherapy and palliative radiotherapy with no success. DISCUSSION: Primary MM of the cervix should be considered in the differential diagnosis of cervical malignancies. Early diagnosis is essential in order to warrant a better prognosis, although there are no cases of cure described.


Subject(s)
Melanoma/pathology , Melanoma/surgery , Uterine Cervical Neoplasms/pathology , Uterine Cervical Neoplasms/surgery , Aged , Fatal Outcome , Female , Humans , Hysterectomy , Neoplasm Staging
18.
Phys Chem Chem Phys ; 11(46): 10890-8, 2009 Dec 14.
Article in English | MEDLINE | ID: mdl-19924323

ABSTRACT

Compaction of negatively charged polyanions by polycations with different characteristics is investigated using Monte Carlo simulation in a coarse-grain model. Two different routes are tested and the results compared. In one, the polycation/polyanion charge ratio is varied by increasing the amount of polycations, keeping all the chain characteristics constant. In the other, the linear charge density of the polycations is altered but their number is kept constant. The set of systems in which the linear charge density changes is used as a model for a system comprising chains with different degrees of ionization under different pH conditions. In both cases, polycation/polyanion charge ratios ranging from 0.25 to 1.25 are addressed. The system with unitary charge ratio is common to both routes. It is seen that, although the overall trends followed by the two sets of systems are similar, marked differences can be discerned both for low charge ratios, and for the higher ones, where the systems are overcharged. Coexistence regimes are clearly detected in some of the systems. The results obtained computationally can be used to guide practical applications.


Subject(s)
Electrolytes/chemistry , Hydrogen-Ion Concentration , Monte Carlo Method , Polyamines/chemistry , Polyelectrolytes , Polymers/chemistry
19.
Acta Med Port ; 4(3): 127-30, 1991.
Article in Portuguese | MEDLINE | ID: mdl-1950660

ABSTRACT

Twelve cases of extreme umbilical blood flow impairement (8 cases with loss of end-diastolic blood flow and 4 cases with reversed flow) found among 658 pregnancies studied by continuous Doppler between April 1st 1989 and March 31st 1990, are reported. The findings were associated to intra-uterine growth retardation (92%), maternal hypertensive disease (50%) and perinatal death (33%); fetal Trisomy 21 was the sole problem in one of the cases with absent end-diastolic frequencies. Our results are discussed and compared to similar data reported recently. Clinical management is proposed, according to umbilical blood flow patterns, length of gestation and underlying clinical situations.


Subject(s)
Fetal Blood , Fetal Diseases/physiopathology , Umbilical Arteries/diagnostic imaging , Blood Flow Velocity , Diastole , Female , Humans , Pregnancy , Ultrasonography
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