A Hardware Encoder-Based Synchronization Method for a Fast Terahertz TDS Imaging System Based on the ECOPS Scheme.

In this paper, we report our use of a hardware encoder-based synchronization method for a fast terahertz time-domain spectroscopy raster scanner built with the commercially available TeraFlash Smart platform. We describe the principles of our method, including our incorporation of synchronization signals from various devices included in the scanner. We also describe its implementation in a microcontroller with a dedicated counter. By such means, a fast scanning mode was obtained, which was 35 times faster than a traditional step-by-step approach. To validate the proposed synchronization method, we carried out measurements using the USAF 1951 resolution test and a fiberglass plate with a set of intentionally introduced defects. Our results confirmed that the TDS scanner with the developed synchronization method was able to capture high-quality images with resolutions as high as those obtained using traditional step-by-step scanning, but with significantly reduced scanning times.

Lipid Peroxidation as a Possible Factor Affecting Bone Resorption in Obese Subjects-Preliminary Research.

Oxidative stress, which promotes bone catabolism, also affects the quality of bone tissue. We aimed to assess the impact of metabolic disorders and oxidant-antioxidant imbalance associated with primary obesity on bone resorption and formation processes. Anthropometric parameters, metabolic variables, oxidative stress indicators (malondialdehyde, vitamins A and E, uric acid, superoxide dismutase, catalase, glutathione peroxidase, type 1 paraoxonase, iron-reducing plasma antioxidant power) and markers of bone turnover (type I procollagen N-terminal propeptide and the type I collagen C-terminal cross-linked telopeptide; P1NP and CTX) were assessed in 108 Polish participants. Under the influence of oxidative stress, both enzymatic and non-enzymatic defense mechanisms were stimulated in obese subjects, especially in women, who had increased lipid peroxidation and activity of catalase (particularly in first-degree obesity) and decreased vitamin E concentration. The process of lipid peroxidation, as well as the weakening of the bone formation, was strongly manifested in women at a BMI range of 35.0-39.9 kg/m2 but not at BMI > 40.0 kg/m2, but it had a comprehensive negative impact on bone turnover in obese men. Obesity and its degree of advancement significantly affected the decrease in the concentration of the marker of bone formation-P1NP-only in the plasma of women. Excessive body weight had no effect on the value of the bone resorption marker in plasma, regardless of gender. Our results confirm the existence of the "obesity paradox" in the aspect of bone tissue metabolism and suggest that a specific body weight threshold changed the molecular response of the tissue.

Application of 3D Printing in Bone Grafts.

The application of 3D printing in bone grafts is gaining in importance and is becoming more and more popular. The choice of the method has a direct impact on the preparation of the patient for surgery, the probability of rejection of the transplant, and many other complications. The aim of the article is to discuss methods of bone grafting and to compare these methods. This review of literature is based on a selective literature search of the PubMed and Web of Science databases from 2001 to 2022 using the search terms "bone graft", "bone transplant", and "3D printing". In addition, we also reviewed non-medical literature related to materials used for 3D printing. There are several methods of bone grafting, such as a demineralized bone matrix, cancellous allograft, nonvascular cortical allograft, osteoarticular allograft, osteochondral allograft, vascularized allograft, and an autogenic transplant using a bone substitute. Currently, autogenous grafting, which involves removing the patient's bone from an area of low aesthetic importance, is referred to as the gold standard. 3D printing enables using a variety of materials. 3D technology is being applied to bone tissue engineering much more often. It allows for the treatment of bone defects thanks to the creation of a porous scaffold with adequate mechanical strength and favorable macro- and microstructures. Bone tissue engineering is an innovative approach that can be used to repair multiple bone defects in the process of transplantation. In this process, biomaterials are a very important factor in supporting regenerative cells and the regeneration of tissue. We have years of research ahead of us; however, it is certain that 3D printing is the future of transplant medicine.

Fast THz-TDS Reflection Imaging with ECOPS-Point-by-Point versus Line-by-Line Scanning.

We built a high-speed TDS setup with the use of electronically controlled optical sampling (ECOPS), which can measure up to 1600 terahertz pulses per second. The movement of the sample was provided by two fast-speed motorized linear stages constituting the gantry. We developed a flat-bar-based metal marker approach for the synchronization of continuous line-by-line scans. We carefully compared the performance of the terahertz reflection time-domain spectroscopy (TDS) scanner operating in a slow point-by-point and a one-hundred-times faster line-by-line imaging scheme. We analyzed images obtained for both schemes for a uniform metallic breadboard with holes, as well as a glass composite sample with defects. Although the measurement time was reduced by 100 times in terms of the line-by-line scheme, the overall performance in both schemes was almost identical in terms of the defects' sizes, shapes and locations. The results proved that the proposed ECOPS TDS system can provide uniform and extremely fast scanning without any deterioration in image quality.

Low-Cost Cranioplasty-A Systematic Review of 3D Printing in Medicine.

The high cost of biofabricated titanium mesh plates can make them out of reach for hospitals in low-income countries. To increase the availability of cranioplasty, the authors of this work investigated the production of polymer-based endoprostheses. Recently, cheap, popular desktop 3D printers have generated sufficient opportunities to provide patients with on-demand and on-site help. This study also examines the technologies of 3D printing, including SLM, SLS, FFF, DLP, and SLA. The authors focused their interest on the materials in fabrication, which include PLA, ABS, PET-G, PEEK, and PMMA. Three-dimensional printed prostheses are modeled using widely available CAD software with the help of patient-specific DICOM files. Even though the topic is insufficiently researched, it can be perceived as a relatively safe procedure with a minimal complication rate. There have also been some initial studies on the costs and legal regulations. Early case studies provide information on dozens of patients living with self-made prostheses and who are experiencing significant improvements in their quality of life. Budget 3D-printed endoprostheses are reliable and are reported to be significantly cheaper than the popular counterparts manufactured from polypropylene polyester.

Diagnostics of Articular Cartilage Damage Based on Generated Acoustic Signals Using ANN-Part II: Patellofemoral Joint.

Cartilage loss due to osteoarthritis (OA) in the patellofemoral joint provokes pain, stiffness, and restriction of joint motion, which strongly reduces quality of life. Early diagnosis is essential for prolonging painless joint function. Vibroarthrography (VAG) has been proposed in the literature as a safe, noninvasive, and reproducible tool for cartilage evaluation. Until now, however, there have been no strict protocols for VAG acquisition especially in regard to differences between the patellofemoral and tibiofemoral joints. The purpose of this study was to evaluate the proposed examination and acquisition protocol for the patellofemoral joint, as well as to determine the optimal examination protocol to obtain the best diagnostic results. Thirty-four patients scheduled for knee surgery due to cartilage lesions were enrolled in the study and compared with 33 healthy individuals in the control group. VAG acquisition was performed prior to surgery, and cartilage status was evaluated during the surgery as a reference point. Both closed (CKC) and open (OKC) kinetic chains were assessed during VAG. The selection of the optimal signal measures was performed using a neighborhood component analysis (NCA) algorithm. The classification was performed using multilayer perceptron (MLP) and radial basis function (RBF) neural networks. The classification using artificial neural networks was performed for three variants: I. open kinetic chain, II. closed kinetic chain, and III. open and closed kinetic chain. The highest diagnostic accuracy was obtained for variants I and II for the RBF 9-35-2 and MLP 10-16-2 networks, respectively, achieving a classification accuracy of 98.53, a sensitivity of 0.958, and a specificity of 1. For variant III, a diagnostic accuracy of 97.79 was obtained with a sensitivity and specificity of 0.978 for MLP 8-3-2. This indicates a possible simplification of the examination protocol to single kinetic chain analyses.

Diagnostics of Articular Cartilage Damage Based on Generated Acoustic Signals Using ANN-Part I: Femoral-Tibial Joint.

Osteoarthritis (OA) is a chronic, progressive disease which has over 300 million cases each year. Some of the main symptoms of OA are pain, restriction of joint motion and stiffness of the joint. Early diagnosis and treatment can prolong painless joint function. Vibroarthrography (VAG) is a cheap, reproducible, non-invasive and easy-to-use tool which can be implemented in the diagnostic route. The aim of this study was to establish diagnostic accuracy and to identify the most accurate signal processing method for the detection of OA in knee joints. In this study, we have enrolled a total of 67 patients, 34 in a study group and 33 in a control group. All patients in the study group were referred for surgical treatment due to intraarticular lesions, and the control group consisted of healthy individuals without knee symptoms. Cartilage status was assessed during surgery according to the International Cartilage Repair Society (ICRS) and vibroarthrography was performed one day prior to surgery in the study group. Vibroarthrography was performed in an open and closed kinematic chain for the involved knees in the study and control group. Signals were acquired by two sensors placed on the medial and lateral joint line. Using the neighbourhood component analysis (NCA) algorithm, the selection of optimal signal measures was performed. Classification using artificial neural networks was performed for three variants: I-open kinetic chain, II-closed kinetic chain, and III-open and closed kinetic chain. Vibroarthrography showed high diagnostic accuracy in determining healthy cartilage from cartilage lesions, and the number of repetitions during examination can be reduced only to closed kinematic chain.

Robot-Assisted Autism Therapy (RAAT). Criteria and Types of Experiments Using Anthropomorphic and Zoomorphic Robots. Review of the Research.

Supporting the development of a child with autism is a multi-profile therapeutic work on disturbed areas, especially understanding and linguistic expression used in social communication and development of social contacts. Previous studies show that it is possible to perform some therapy using a robot. This article is a synthesis review of the literature on research with the use of robots in the therapy of children with the diagnosis of early childhood autism. The review includes scientific journals from 2005-2021. Using descriptors: ASD (Autism Spectrum Disorders), Social robots, and Robot-based interventions, an analysis of available research in PubMed, Scopus and Web of Science was done. The results showed that a robot seems to be a great tool that encourages contact and involvement in joint activities. The review of the literature indicates the potential value of the use of robots in the therapy of people with autism as a facilitator in social contacts. Robot-Assisted Autism Therapy (RAAT) can encourage child to talk or do exercises. In the second aspect (prompting during a conversation), a robot encourages eye contact and suggests possible answers, e.g., during free conversation with a peer. In the third aspect (teaching, entertainment), the robot could play with autistic children in games supporting the development of joint attention. These types of games stimulate the development of motor skills and orientation in the body schema. In future work, a validation test would be desirable to check whether children with ASD are able to do the same with a real person by learning distrust and cheating the robot.

Alteration within the Hippocampal Volume in Patients with LHON Disease-7 Tesla MRI Study.

PURPOSE: The aim of this study was to assess the volumetry of the hippocampus in the Leber's hereditary optic neuropathy (LHON) of blind patients. METHODS: A total of 25 patients with LHON were randomly included into the study from the national health database. A total of 15 patients were selected according to the inclusion criteria. The submillimeter segmentation of the hippocampus was based on three-dimensional spoiled gradient recalled acquisition in steady state (3D-SPGR) BRAVO 7T magnetic resonance imaging (MRI) protocol. RESULTS: Statistical analysis revealed that compared to healthy controls (HC), LHON subjects had multiple significant differences only in the right hippocampus, including a significantly higher volume of hippocampal tail (p = 0.009), subiculum body (p = 0.018), CA1 body (p = 0.002), hippocampal fissure (p = 0.046), molecular layer hippocampus (HP) body (p = 0.014), CA3 body (p = 0.006), Granule Cell (GC) and Molecular Layer (ML) of the Dentate Gyrus (DG)-GC ML DG body (p = 0.003), CA4 body (p = 0.001), whole hippocampal body (p = 0.018), and the whole hippocampus volume (p = 0.023). DISCUSSION: The ultra-high-field magnetic resonance imaging allowed hippocampus quality visualization and analysis, serving as a powerful in vivo diagnostic tool in the diagnostic process and LHON disease course assessment. The study confirmed previous reports regarding volumetry of hippocampus in blind individuals.

Analysis of Trace Elements in Human Brain: Its Aim, Methods, and Concentration Levels.

Trace elements play a crucial role in many biochemical processes, mainly as components of vitamins and enzymes. Although small amounts of metal ions have protective properties, excess metal levels result in oxidative injury, which is why metal ion homeostasis is crucial for the proper functioning of the brain. The changes of their level in the brain have been proven to be a risk factor for Alzheimer's, Parkinson's, and Huntington's diseases, as well as amyotrophic lateral sclerosis. Therefore, it is currently an important application of various analytical methods. This review covers the most important of them: inductively coupled ground mass spectrometry (ICP-MS), flame-induced atomic absorption spectrometry (FAAS), electrothermal atomic absorption spectrometry (GFAAS), optical emission spectrometry with excitation in inductively coupled plasma (ICP-OES), X-ray fluorescence spectrometry (XRF), and neutron activation analysis (NAA). Additionally, we present a summary of concentration values found by different research groups.

Age is not associated with increased surgical complications in patients after laparoscopic sleeve gastrectomy.

INTRODUCTION: Age is considered as a risk factor in bariatric surgery. The observation was made on the basis of results from studies where patients underwent different type of surgery, but laparoscopic sleeve gastrectomy (LSG) was not among them. It is necessary to reevaluate the association of age with adverse events in the group of patients after LSG. AIM: To investigate the association of age with surgery-related adverse events in patients after LSG. MATERIAL AND METHODS: Retrospective analysis of medical data was performed. The study involved 345 patients who underwent LSG in our institution between January 2013 and December 2014. The patients were subdivided by age into four groups according to quartiles. In 30-day follow-up adverse events were evaluated. We considered the presence of the following events as the endpoint of our study: death, medical events and surgical events. RESULTS: In general, we observed adverse events in 36 (10.4%) patients. The mortality rate in our study was 0.59%. Nineteen events were surgical and 18 medical. In 1 patient a surgical event was associated with a medical event. Bleeding was the most common surgical event and was observed in 17 (4.9%) cases. Age was not associated with surgical events (OR = 1.032, 95% CI: 0.991-1.075, p = 0.33) or medical events (OR = 0.997, 95% CI: 0.956-1.039, p = 0.89). CONCLUSIONS: The LSG is a safe bariatric procedure with low mortality. Bleeding is the most frequent surgical complication. Our findings suggest that age is not associated with increased risk of surgical or medical adverse events after LSG.

Prediction of acute pancreatitis in the earliest stages - role of biochemical parameters and histopathological changes.

For many years, there has been a search for a set of biochemical parameters that could facilitate the assessment of severity, prognosis, and administration of early and appropriate treatment in acute pancreatitis. Administration of treatment within the first 48 hours since admission is associated with many problems of distinguishing patients with a mild form of acute pancreatitis (AP) from those with a severe form of acute pancreatitis. STUDY AIM: To assess the relationship between the extent of change in the concentration of 10 selected biochemical indicators: amylase, lipase, total bilirubin, creatinine, uric acid, aspartate transaminase, alanine transaminase, glucose, magnesium, and iron and histopathological lesions in the pancreas within 2 and 6 hours since induction of AP. The selected time periods correspond to the first and the second day of the disease in people, respectively. MATERIAL AND METHODS: The experiments were conducted in 110 male Wistar rats weighing from 250 to 300 g. Experimental animals were divided into three groups: Z - a group in which the ranges of the studied factors and histological structure were established; K - a group of animals operated on which were injected with 0.9% NaCl into the biliary-pancreatic duct; E - a group of animals operated on in which acute pancreatitis was induced by an injection of 5% sodium taurocholate into the biliary-pancreatic duct. Animals from the K and E groups were randomly assigned to one of five subgroups from which the material for biochemical and histological examinations was collected at 2 h and 6 h since the induction of AP. Whole pancreases were dissected for histological examinations, and the samples were dyed with hematoxylin and saturated alcoholic eosin solution. The degree of pancreatic lesions was assessed according to the Spormann score. Quantitative variables were characterized by arithmetic means, standard deviations, medians, minimum and maximum values, and 95% CIs. RESULTS: In histological preparations from rats from the E group, after 2 hours, edematous lesions, neutrophilic infiltrations in the pancreatic parenchyma, together with single petechiae started to appear and were observed. After 6 hours, the lesions became more intense, and minor foci of coagulation necrosis and minor foci of purulent inflammation in the fatty tissue appeared. Within 2 hours, statistically significant differences in the amount of four markers: creatinine, ALT, amylase, and magnesium were observed. After six hours, statistically significant differences in the amount of two markers: AST and glucose were seen. The correlations between histological assessments according to the Spormann scale and biochemical indicators were investigated, and it was observed that within 2 hours the intensity of pancreatitis increased together with an increase in AST. In group K, within 6 hours, the intensity of inflammatory infiltration increased together with an increase in creatinine concentration (correlation coefficient 0.95; p=0.0138). In group E, in the period of 2 hours, lesion intensity in the form of inflammatory infiltration increased together with an increase in the AST level (correlation coefficient 0.90; p=0.0063) and an increase in the iron level (correlation coefficient 0.78; p=0.0399). In the same group and in the same period, an increase in the AST level (correlation coefficient 0.79; p=0.0343) was associated with an increase in lesion intensity in the form of ecchymoses. Inflammatory infiltration increased (correlation coefficient -0.87; p=0.0117) within 6 hours, whereas the creatinine level decreased. Interesting results were obtained with the use of regression analysis - forward stepwise regression. In the period of 2 hours, if the creatinine level increased by 1, the intensity of lesions in acute pancreatitis decreased by 9.02, according to the Spormann score, while the other variables remained at a stable level. However, if ALT level increased by 1, the intensity of lesions in acute pancreatitis increased by 0.02, according to the Spormann score; and if the amylase level increased by 1, the intensity of lesions in acute pancreatitis increased by 0.01, according to the Spormann score, while the other variables remained at a stable level. CONCLUSIONS: Histopathological lesions occurred prior to changes in laboratory test results, whereas significant correlations with Spormann scores were seen in the case of changes in AST and creatinine levels. The study results confirm the fact that diagnostics in acute pancreatitis is very difficult and requires monitoring of many laboratory parameters.

Telemedical systems for home monitoring of patients with chronic conditions in rural environment.

This paper describes the requirements and possible implementations of a telemedical system. The idea of remote patient monitoring is a point of interest for researchers in Poland, and is also in high demand in fields such as diabetology, cardiology, and geriatrics, among others. Aging society, medical care costs and many other factors make remote patient care a promising idea for the future. For each and every condition, a specialized type of sensor must be used to allow specific measurements to be performed. Moreover, a local data storage and communication device must be provided for the sensor to be able to relay data to the station. A smart phone can be used perform such tasks. By implementing such remote diagnostic systems it is possible to collect, process, store and present vital medical data that can be used immediately to perform diagnosis, or later as reference for expert systems. The 'Borboleta' and 'SaguiSaúde' systems already implemented can serve as a base for system analysis. The systems provide necessary functions and can be used as reference. Many factors contribute to the success of the telemedical system, such as ease of access, scalability, safety, platform independence, and many others. For easier implementation and clarity, the system should be divided into independent layers, which will also make it easier to modify and integrate into other medical systems. Making the system easy to use for patients, medical staff, administrators and data managers makes the task of system design especially challenging. One must decide which information is necessary for each type of user and provide them clearly and in an orderly fashion.

Meteorological parameters and severity of acute pulmonary embolism episodes.

Frequency of acute pulmonary embolism episodes has been previously shown to correlate significantly with meteorological factors in the period preceding their occurrence. The purpose of the study was to analyze the relation of meteorological factors and the severity of acute pulmonary embolism, expressed by the CT-based pulmonary obstruction score. A retrospective analysis of medical data of 182 consecutive patients with acute pulmonary embolism diagnosed with CT pulmonary angiography was performed. Severity of pulmonary obstruction was assessed by analysis of CT pulmonary angiography examinations, and defined with pulmonary obstruction score by Qanadli et al. The study group was divided into low (L group, 95 patients) and high PE severity (H group, 87 patients), with a cutoff value of 50% of maximum pulmonary obstruction score. Meteorological data collected for the relevant time period were: air temperature, humidity, atmospheric pressure, visibility, wind speed and precipitation. No significant differences in seasonal distribution of pulmonary embolism episodes were observed. Episodes of more severe pulmonary embolism were preceded by periods of lower atmospheric pressure (1,016.35 hPA for group H, vs. 1,016.35 hPa for group L, p = 0.022). No significant relations between other meteorological factors and severity of PE were observed. The reported finding shows the need of further research on the nature of meteorological factors influence on the course of pulmonary embolism, which should be analyzed not ony regarding the frequency, but also severity of PE episodes.