Search

OBJECTIVES/HYPOTHESIS Identification of parathyroid glands and adjacent tissues intraoperatively can be quite challenging because of their small size, variable locations, and indistinct external features. The objective of this study is to test the efficacy of the dynamic optical contrast imaging (DOCI) technique as a tool in specifically differentiating parathyroid tissue and adjacent structures, facilitating efficient and reliable tissue differentiation. STUDY DESIGN Prospective study. METHODS Both animal and human tissues were included in this study. Fresh specimens were imaged with DOCI and subsequently processed for hematoxylin and eosin (H&E) stain. The DOCI images were analyzed and compared to the H&E results as ground truth. RESULTS In both animal and human experiments, significant DOCI contrast was observed between parathyroid glands and adjacent tissue of all types. Region of interest analysis revealed most distinct DOCI values for each tissue when using 494 and 572 nm-specific band pass filter for signal detection (P

A central challenge of medical imaging studies is to extract quantitative biomarkers that characterize pathology or predict disease outcomes. In high-resolution, high-quality magnetic resonance images (MRI), state-of-the-art approaches have performed well. However, such methods may not translate to low resolution, lower quality images acquired on MRI scanners with lower magnetic field strength. Therefore, in low-resource settings where low field scanners are more common and there is a shortage of available radiologists to manually interpret MRI scans, it is essential to develop automated methods that can accommodate lower quality images and augment or replace manual interpretation. Motivated by a project in which a cohort of children with cerebral malaria were imaged using 0.35 Tesla MRI to evaluate the degree of diffuse brain swelling, we introduce a fully automated framework to translate radiological diagnostic criteria into image-based biomarkers. We integrate multi-atlas label fusion, which leverages high-resolution images from another sample as prior spatial information, with parametric Gaussian hidden Markov models based on image intensities, to create a robust method for determining ventricular cerebrospinal fluid volume. We further propose normalized image intensity and texture measurements to determine the loss of gray-to-white matter tissue differentiation and sulcal effacement. These integrated biomarkers are found to have excellent classification performance for determining severe cerebral edema due to cerebral malaria.

Objective Quantitative MRI (qMRI) methods provide versatile neuroradiological applications and are a hot topic in research. The degree of their clinical implementation is however barely known. This survey was created to illuminate which and how qMRI techniques are currently applied across Europe. Methods In total, 4753 neuroradiologists from 27 countries received an online questionnaire. Demographic and professional data, experience with qMRI techniques in the brain and head and neck, usage, reasons for/against application, and knowledge of the QIBA and EIBALL initiatives were assessed. Results Two hundred seventy-two responders in 23 countries used the following techniques clinically (mean values in %): DWI (82.0%, n = 223), DSC (67.3%, n = 183), MRS (64.3%, n = 175), DCE (43.4%, n = 118), BOLD-fMRI (42.6%, n = 116), ASL (37.5%, n = 102), fat quantification (25.0%, n = 68), T2 mapping (16.9%, n = 46), T1 mapping (15.1%, n = 41), PET-MRI (11.8%, n = 32), IVIM (5.5%, n = 15), APT-CEST (4.8%, n = 13), and DKI (3.3%, n = 9). The most frequent usage indications for any qMRI technique were tissue differentiation (82.4%, n = 224) and oncological monitoring (72.8%, n = 198). Usage differed between countries, e.g. ASL: Germany (n = 13/63; 20.6%) vs. France (n = 31/40; 77.5%). Neuroradiologists endorsed the use of qMRI because of an improved diagnostic accuracy (89.3%, n = 243), but 50.0% (n = 136) are in need of better technology, 34.9% (n = 95) wish for more communication, and 31.3% need help with result interpretation/generation (n = 85). QIBA and EIBALL were not well known (12.5%, n = 34, and 11.0%, n = 30). Conclusions The clinical implementation of qMRI methods is highly variable. Beyond the aspect of readiness for clinical use, better availability of support and a wider dissemination of guidelines could catalyse a broader implementation. Key Points • Neuroradiologists endorse the use of qMRI techniques as they subjectively improve diagnostic accuracy. • Clinical implementation is highly variable between countries, techniques, and indications. • The use of advanced imaging could be promoted through an increase in technical support and training of both doctors and technicians.

Study design Experimental in-vivo animal study. Objective The aim of this study was to evaluate an Artificial Intelligence (AI)-enabled ultrasound imaging system's ability to detect, segment, classify, and display neural and other structures during trans-psoas spine surgery. Summary of background data Current methodologies for intraoperatively localizing and visualizing neural structures within the psoas are limited and can impact the safety of lateral lumbar interbody fusion (LLIF). Ultrasound technology, enhanced with AI-derived neural detection algorithms, could prove useful for this task. Methods The study was conducted using an in vivo porcine model (50 subjects). Image processing and machine learning algorithms were developed to detect neural and other anatomic structures within and adjacent to the psoas muscle while using an ultrasound imaging system during lateral lumbar spine surgery (SonoVision,™ Tissue Differentiation Intelligence, USA). The imaging system's ability to detect and classify the anatomic structures was assessed with subsequent tissue dissection. Dice coefficients were calculated to quantify the performance of the image segmentation. Results The AI-trained ultrasound system detected, segmented, classified, and displayed nerve, psoas muscle, and vertebral body surface with high sensitivity and specificity. The mean Dice coefficient score for each tissue type was >80%, indicating that the detected region and ground truth were >80% similar to each other. The mean specificity of nerve detection was 92%; for bone and muscle, it was >95%. The accuracy of nerve detection was >95%. Conclusion This study demonstrates that a combination of AI-derived image processing and machine learning algorithms can be developed to enable real-time ultrasonic detection, segmentation, classification, and display of critical anatomic structures, including neural tissue, during spine surgery. AI-enhanced ultrasound imaging can provide a visual map of important anatomy in and adjacent to the psoas, thereby providing the surgeon with critical information intended to increase the safety of LLIF surgery.Level of Evidence: N/A.

In this paper we aim to improve the understanding of the relationship between unilateral-uniplanar external fixator design parameters and their influences on fixator performance. Stability and strength of bone-fixator construct as well as the quality of healing were defined as our major concerns in order to evaluate the performance of fixator. The roles of six key design parameters were assessed during the early stage of healing by using finite element models. Tissue differentiation within the callus was predicted through the implementation of a mechanoregulation theory of bone healing. Taguchi and ANOVA methods were used to achieve optimal design sets for outputs and to determine contribution percentage of each design parameter on outputs. For improving overall fixator performance, optimal set of design parameters consisting of 2 mm, 8 mm, 120 mm, 20 GPa, 50 mm and 20 mm were determined by Taguchi for pin diameter, rod diameter, rod elevation, fixator Young’s modulus, distance of the nearest pin to fracture site and distance between adjacent pins, respectively. Also, results of ANOVA revealed that rod elevation is the most important design parameter, with 43 % effectiveness on overall fixator performance, which was followed by fixator material and pin diameter with 28 % and 19 %, respectively. Results of this study can assist orthopedic surgeons to achieve an optimal fixator device with respect to the patient’s condition and give insight into the importance of different design parameters.

Dynamization, increasing the interfragmentary movement (IFM) by reducing the fixation stiffness from a rigid to a more flexible condition, is widely used clinically to promote fracture healing. However, it remains unknown how dynamization degree (relative change in fixation stiffness/IFM from a rigid to a flexible fixation) affects bone healing at various stages. To address this issue, we used a fuzzy logic-based mechano-regulated tissue differentiation algorithm on published experimental data from a sheep osteotomy healing model. We applied a varied degree of dynamization, from 0 (fully rigid fixation) to 0.9 (90% reduction in stiffness relative to the rigid fixation) after 1, 2, 3, and 4 weeks of osteotomy (R1wF, R2wF, R3wF, and R4wF) and computationally evaluated bone regeneration and biomechanical integrity over the healing process of 8 weeks. Compared with the constant rigid fixation, early dynamization (R1wF and R2wF) led to delays in bone bridging and biomechanical recovery of the osteotomized bone. However, the effect of early dynamization on healing was dependent of the degree of dynamization. Specifically, a higher dynamization degree (e.g., 0.9 for R1wF) led to a prolonged delay in bone bridging and largely unrecovered bending stiffness (48% relative to the intact bone), whereas a moderate degree of dynamization (e.g., 0.5 or 0.7) significantly enhanced bone formation and biomechanical properties of the osteotomized bone. These results suggest that dynamization degree and timing interactively affect the healing process. A combination of early dynamization with a moderate degree could enhance the ultimate biomechanical recovery of the fractured bone.

This work proposes a new online monitoring method for an assistance during laser osteotomy. The method allows differentiating the type of ablated tissue and the applied dose of laser energy. The setup analyzes the laser-induced acoustic emission, detected by an airborne microphone sensor. The analysis of the acoustic signals is carried out using a machine learning algorithm that is pre-trained in a supervised manner. The efficiency of the method is experimentally evaluated with several types of tissues, which are: skin, fat, muscle, and bone. Several cutting-edge machine learning frameworks are tested for the comparison with the resulting classification accuracy in the range of 84-99%. It is shown that the datasets for the training of the machine learning algorithms are easy to collect in real-life conditions. In the future, this method could assist the doctors during laser osteotomy, minimizing the damage of the nearby healthy tissues and provide cleaner pathologic tissue removal.

Ruptures to tendons are common and costly, and no clinical consensus exists on the appropriate treatment and rehabilitation regimen to promote their healing as well as full recovery of functionality. Although mechanobiology is known to play an important role in tendon regeneration, the understanding of how mechano-regulated processes affect tendon healing needs further clarification. Many small-animal studies, particularly in rats and mice, have characterized the progression of healing in terms of geometrical, structural, compositional, mechanical, and cellular properties. Some of the properties are also studied under different mechanical loading regimens. The focus of this review is to summarize and generalize the information in the literature regarding spatial and temporal differentiation of tendon properties during rodent tendon healing following full-tendon transection, as well as how this is affected by altered in vivo loading regimens. Funding Agencies|European UnionEuropean Commission [713645]; Knut and Alice Wallenberg KAW Foundation (Wallenberg Academy) [2017.0221]; European Research Council (ERC) under the European UnionEuropean Research Council (ERC) [101002516]

La resonancia magnética (RM), como técnica de diagnóstico médico, aporta imágenes de excelente diferenciación tisular sin la utilización de radiaciones ionizantes permitiendo estudiar múltiples lesiones y enfermedades. La conservación de un entorno seguro en RM requiere el conocimiento y la vigilancia constante del profesional de la salud en ese sector, sobre todo ante pacientes con implantes biomédicos metálicos, como lo son los traumatológicos-ortopédicos. El objetivo de nuestro trabajo es compartir el protocolo de bioseguridad llevado adelante ante la decisión de realizar RM en un paciente con implante ortopédico-traumatológico del que se desconoce el material, para que otros colegas, ante esta situación, conozcan los pasos a seguir y así poder realizar el estudio exitosamente.

Background As far as gastric cancer is concerned, there is a lack of specific early diagnostic biomarkers in clinical diagnosis. Circular RNAs (circRNAs) have been found to be stable in gastric cancer tissues and plasma, so they have the potential to become new type of diagnostic biomarkers for gastric cancer. Materials and Methods The hsa_circ_0001811 expressions in gastric cancer tissues and paired non‐cancer tissues, preoperative and postoperative plasma of patients with gastric cancer, and plasma of healthy volunteers were detected using quantitative reverse transcription‐polymerase chain reaction. The receiver operating characteristic (ROC) curves were drawn; and the combined ROC curves were used to analyze their diagnostic values. The correlation between the plasma or tissue hsa_circ_0001811 levels and the clinicopathological factors of gastric cancer was further analyzed. Results Hsa_circ_0001811 was found to be lowly expressed in gastric cancer tissues and plasma from patients with gastric cancer. The area under the ROC curve (AUC) in the gastric cancer tissues and the plasma of patients with gastric cancer was 0.658 and 0.747, respectively. The AUC increased to 0.824 after combination of both. The expression level of hsa_circ_0001811 in gastric cancer tissue correlated with carcinoembryonic antigen (CEA) (P = .0347), tissue differentiation (P = .0138), and lymph node metastasis (P = .0234), while plasma hsa_circ_0001811 level was related to carbohydrate antigen (CA19‐9) (P = .0278), lymph node metastasis (P = .0469), distant metastasis (P = .0384), and age (P = .0085). Conclusions The above results indicate that hsa_circ_0001811 may become a new biomarker for clinical diagnosis of gastric cancer., Sanger sequence results of qRT‐PCR products of hsa_circ_0001811 are consistent with the sequence of target circRNA. Compared with paired non‐cancer tissues, hsa_circ_0001811 was low expressed in gastric cancer tissues (2A); and the expression of plasma specimens one day before surgery in gastric cancer patients was lower, then those in ten days after surgery and plasma samples of healthy volunteers (2B). The AUC of hsa_circ_0001811 in gastric cancer tissues was 0.658, while the AUC in plasma was 0.747. When tissues and plasma were combined used, the AUC increased to 0.824, further showing the higher diagnostic value of hsa_circ_0001811.

Background: The effect of the short-term bone healing process is typically neglected in numerical models of bone remodeling for dental implants. In this study, a hybrid two-step algorithm was proposed to enable a more accurate prediction for the performance of dental implants. Methods: A mechano-regulation algorithm was firstly used to simulate the tissue differentiation around a dental implant during the short-term bone healing. Then, the result was used as the initial state of the bone remodeling model to simulate the long-term healing of the bones. The algorithm was implemented by a 3D finite element model. Results: The current hybrid model reproduced several features which were discovered in the experiments, such as stress shielding effect, high strength bone connective tissue bands, and marginal bone loss. A reasonable location of bone resorptions and the stability of the dental implant is predicted, compared with those predicted by the conventional bone remodeling model. Conclusions: The hybrid model developed here predicted bone healing processes around dental implants more accurately. It can be used to study bone healing before implantation surgery and assist in the customization of dental implants.

Distraction osteogenesis (DO) is a mechanobiological process of producing new bone and overlying soft tissues through the gradual and controlled distraction of surgically separated bone segments. The process of bone regeneration during DO is largely affected by distraction parameters. In the present study, a distraction strategy with varying distraction rates (i.e., “rate-varying distraction”) is proposed, with the aim of shortening the distraction time and improving the efficiency of DO. We hypothesized that faster and better healing can be achieved with rate-varying distractions, as compared with constant-rate distractions. A computational model incorporating the viscoelastic behaviors of the callus tissues and the mechano-regulatory tissue differentiation laws was developed and validated to predict the bone regeneration process during DO. The effect of rate-varying distraction on the healing outcomes (bony bridging time and bone formation) was examined. Compared to the constant low-rate distraction, a low-to-high rate-varying distraction provided a favorable mechanical environment for angiogenesis and bone tissue differentiation, throughout the distraction and consolidation phase, leading to an improved healing outcome with a shortened healing time. These results suggest that a rate-varying clinical strategy could reduce the overall treatment time of DO and decrease the risk of complications related to the external fixator.

Craniofacial morphogenesis is an intricate developmental process in 3D, which therefore merits visualization and investigation in 3D. To better understand the process, we utilize μCT imaging, and describe a method to calibrate each cone beam μCT individually. Calibration is necessary, because during development, fetuses undergo tissue differentiation, which affects the acquisition process for radiographic images. Additionally, tissue fixation and conservation agents may influence the physical properties of the specimens and may affect image acquisition. After taking a μCT scan from each specimen, we separated a horizontal slice from each neck (which is inconsequential to our question with relation to the whole head). These neck specimens were prepared as horizontal histological serial sections and stained. With these as a reference, the μCT visualization parameters could be adjusted until they matched the selected virtual section planes, which correspond exactly to the planes of the histological sections with a precision (pixel size) of 0.69 μm.

The distribution of malignant tumors is strongly related to gender due to sex-related organ and tissue differentiation. Neoplasias of the adrenal glands are relatively common and typically benign. Mainly based on our recently published contributions, we analyzed the influence of gender on type of tumors, complexity of surgery, and long-term outcome. Cortisol-secreting adrenal tumors are more often diagnosed in female patients, while the incidence of Conn’s syndrome and pheochromocytoma is similar between male and female patients. Adrenalectomy is more difficult in male patients because of longer operating time and higher blood loss. The probability of cure in male patients with Conn’s syndrome is significantly lower. Gender does not influence long-term results in adrenal hypercortisolism and pheochromocytomas.

An introduction of innovative minimally invasive methods like multimodal optical coherence tomography (OCT) with polarization-sensitivity and angiography modes for intrasurgical guidance appears to be a critical challenge for the modern neurooncology. This study aimed to develop a new instrument for targeted stereotactic brain biopsy based on cross-polarization (CP) OCT realized in standard biopsy needle to increase the safety of ongoing neurosurgical procedures. Experimental studies in vivo on the healthy rat’s brain allow detecting blood vessels in the process of moving the biopsy needle along the brain surface and detect tissue type (cerebral cortex or white matter) when the needle went inside the brain. The images was assessed by visual criteria. However, CP OCT signal quantification methods will increase the sensitivity/specificity for the tissue type differentiation and blood vessels detection. The potential of CP OCT as an effective instrument for OCT-guided stereotactic biopsy of brain tumors was demonstrated.

Background To investigate the expression of connexin43( Cx43) and Seprase protein in gastric carcinoma and their clinical significance. Methods Immunohistochemical method was used to detect the expression of Seprase and connexin 43 proteins in 45 specimens of gastric carcinoma and 15 specimens of paired adjacent normal gastric tissue. The relationship between their expression and the clinicopathologic characteristics were statistically analyzed. Results 1: The positive rate of Seprase protein in gastric carcinoma was 71.11%(32/45) higher than that in normal tissue 20.00%(3/15) and with statistical significance (χ2=6.67,p=0.01); The positive rate of connexin 43 protein in gastric carcinoma was 68.89%(30/45) lower than that in normal tissue 100%(15/15) and with statistical significance(χ2=12.09,p=0.001). 2: Connexin 43 protein was related to the age and the degree of tissue differentiation of gastric carcinoma (P Conclusions In gastric carcinoma, Connexin 43 appeared down-expression and seprase appeared up-regulation, That may play important roles in the invasion and metastasis of gastric carcinoma, then provide a new direction for target therapy.

Conventional B-mode ultrasound imaging lacks soft tissue contrast to differentiate various tissue types. Emerging ultrasound imaging technologies have therefore focused on extracting tissue parameters important for tissue differentiation such as scatterer size, tissue elasticity, and micro-vasculatures. Among these technologies, shear wave elastography (SWE) is an approach that measures tissue viscoelastic parameters. Our group has proposed Temporal Enhanced Ultrasound (TeUS) that differentiates tissue types without requiring any external stimuli. Through analytical derivations and simulations, we previously showed that the source of tissue typing information in TeUS is physiological micro-vibrations resulting mainly from perfusion. We further demonstrated that TeUS is sensitive to the size and distributions of scatterers in the tissue, as well as its visco-elasticity. In this paper, we designed ultrasound phantoms to mimic tissue with two different elasticities and two scatterer sizes. A exible microtube was embedded in the phantoms to generate local micro-vibrations. We experimentally demonstrate the relationship between TeUS and SWE and their sensitivity to tissue elasticity and scatterer size. This work indicated that while shear wave measurements are sensitive to the phantoms viscoelasticity, they are not sensitive to ultrasound scatterer size. On the contrary, the TeUS amplitude depends on both scatterer size and tissue viscoelasticity. This work could potentially inform clinicians of choosing imaging modalities and interventions based on each cancer's unique traits and properties.

Small bowel neuroendocrine tumors are clinically challenging to detect and are often found incidentally or with metastatic disease. Specific imaging is used to detect and localize these tumors, and biochemical tests can be used to help identify patients at risk of a carcinoid crisis. Treatment is often multimodal and is determined by tissue differentiation and Ki-67 index.

This paper presents an improved tactile sensor using a piezoelectric bimorph able to differentiate soft materials with similar mechanical characteristics. The final aim is to develop intelligent surgical tools for brain tumour resection using integrated sensors in order to improve tissue tumour delineation and tissue differentiation. The bimorph sensor is driven using a random phase multisine and the properties of contact between the sensor's tip and a certain load are evaluated by means of the evaluation of the nonparametric FRF. An analysis of the nonlinear contributions is presented to show that the use of a linear model is feasible for the measurement conditions. A series of gelatine phantoms were tested. The tactile sensor is able to identify minimal differences in the consistency of the measured samples considering viscoelastic behaviour. A variance analysis was performed to evaluate the reliability of the sensors and to identify possible error sources due to inconsistencies in the preparation method of the phantoms. The results of the variance analysis are discussed showing that ability of the proposed tactile sensor to perform high quality measurements., 16 pages

Hintergrund Die optische Koharenztomographie (OCT) ist ein hochauflosendes bildgebendes Verfahren, das die Darstellung von Gewebestrukturen im Mikrometerbereich zulasst.

Changes in mechanical properties represent one of the driving factors behind cell differentiation during embryonic development. However, measuring these changes without disrupting the normal progression of morphogenesis or destroying the developing organism is not trivial. Brillouin microspectroscopy has been shown to be capable of nocontact, non-destructive and non-disruptive assessment of elastic properties in developing zebrafish embryos. The present study builds upon the previous work, and observes the changes in elasticity during the development of heart and brain in zebrafish embryos from 8 to 28 hpf (hours post-fertilization) at regular intervals. Brillouin microspectroscopy has proved to be a suitable technique to continuously monitor tissue differentiation and the development of individual organs with high spatial resolution without harming the developing organism.

Background: We report two cases of mosaic generalized neurofibromatosis 1 (NF1) and review the history of the classification of segmental neurofibromatosis (SNF; Ricardi type NF-V). Somatic mutations giving rise to limited disease, such as segmental neurofibromatosis are manifestations of mosaicism. If the mutation occurs before tissue differentiation, the clinical phenotype will be generalized disease. Mutations that occur later in development give rise to disease that is confined to a single region. Objectives: Segmental neurofibromatosis is caused by a somatic mutation of neurofibromatosis type 1, and should not be regarded as a distinct entity from neurofibromatosis 1. Cases previously referred to as unilateral or bilateral segmental neurofibromatosis are now best referred to as mosaic generalized or mosaic localized neurofibromatosis 1.

// Jingyu Deng 1 , Han Liang 1 , Rupeng Zhang 1 , Qiuping Dong 2 , Yachao Hou 1 , Jun Yu 3 , Daiming Fan 4 and Xishan Hao 1 1 Department of Gastroenterology, Tianjin Medical University Cancer Hospital, City Key Laboratory of Tianjin Cancer Center and National Clinical Research Center for Cancer, Tianjin, China 2 Central laboratory, Tianjin Medical University Cancer Hospital, City Key Laboratory of Tianjin Cancer Center and National Clinical Research Center for Cancer, Tianjin, China 3 Institute of Digestive Disease, Li Ka Shing Institute of Health Science, Chinese University of HongKong, Shatin, HongKong 4 State Key Laboratory of Cancer Biology and Institute of Digestive Diseases, Xijing Hospital, Fourth Military Medical University, Xi’an, China Correspondence: Xishan Hao, email: // Han Liang, email: // Keywords : Paired box 5, Methylation, Prognosis, Gastric cancer Received : April 16, 2014 Accepted : May 12, 2014 Published : May 14, 2014 Abstract Paired box gene 5 (PAX5), a member of the paired box gene family, is involved in control of organ development and tissue differentiation. In previous study, PAX5 promoter methylation was found in gastric cancer (GC) cells and tissues. At present study, we found that the inconsistently methylated levels of PAX5 promoter were identified in the different GC tissues. The methylated CpG site count and the methylated statuses of four CpG sites (-236, -183, -162, and -152) were significantly associated with the survival of 460 GC patients, respectively. Ultimately, the methylated CpG -236 was the optimal prognostic predictor of patients identified by using the Cox regression with AIC value calculation. These findings indicated that the methylated CpG -236 of PAX5 promoter has the potential applicability for clinical evaluation the prognosis of GC.

Numerous clinical studies have reported cell-based treatments for cartilage regeneration in knee joint osteoarthritis using mesenchymal stem cells (MSCs). However, the post-surgery rehabilitation and weight-bearing times remain unclear. Phenomenological computational models of cartilage regeneration have been only partially successful in predicting experimental results and this may be due to simplistic modeling assumptions and loading conditions of cellular activity. In the present study, we developed a knee joint model of cell and tissue differentiation based on a more mechanistic approach, which was applied to cartilage regeneration in osteoarthritis. First, a phenomenological biphasic poroelastic finite element model was developed and validated according to a previous study. Second, this method was applied to a real knee joint model with a cartilage defect created to simulate the tissue regeneration process. The knee joint model was able to accurately predict several aspects of cartilage regeneration, such as the cell and tissue distributions in the cartilage defect. Additionally, our results indicated that gait cycle loading with flexion was helpful for cartilage regeneration compared to the use of simple weight-bearing loading.

The organization of an Artificial Neural Network (ANN; e.g. the organization in layers, the number of cells per layer and the degree of connectivity between the cells) has a big influence on its abilities (e.g. learning ability). In this article, we present a novel method to organize the nodes and links of an ANN in a biologically motivated manner using virtual embryogenesis (VE). The VE mimics processes observable in biology, like interaction of cells via chemical substances or tissue differentiation. In our system, a virtual embryo consists of individual cells controlled by a genome. These cells can develop to nodes in the ANN during the embryogenetic process. The embryo is implemented as a spatially and temporally discrete multi-agent model. The cells in our model interact with each other via virtual physics and virtual chemistry. With the work at hand, we show that patterns developing in VE are comparable to patterns found during natural embryogenesis. We plan to combine VE with Evolutionary Algorithm...

Active learning is a supervised learning technique that reduces the number of examples required for building a successful classifier, because it can choose the data it learns from. This technique holds promise for many biological domains in which classified examples are expensive and time-consuming to obtain. Most traditional active learning methods ask very specific queries to the Oracle (e.g., a human expert) to label an unlabeled example. The example may consist of numerous features, many of which are irrelevant. Removing such features will create a shorter query with only relevant features, and it will be easier for the Oracle to answer. We propose a generalized query-based active learning (GQAL) approach that constructs generalized queries based on multiple instances. By constructing appropriately generalized queries, we can achieve higher accuracy compared to traditional active learning methods. We apply our active learning method to find differentially DNA methylated regions (DMRs). DMRs are DNA locations in the genome that are known to be involved in tissue differentiation, epigenetic regulation, and disease. We also apply our method on 13 other data sets and show that our method is better than another popular active learning technique.

The role of surgery will certainly change in the next decades. Conservative treatment will conquer some current domains of surgery, such as inflammatory bowel diseases or metabolic disorders. Functional disorders could potentially benefit from better pharmacological agents, but possibly surgical electrical stimulation could become a realistic alternative option. In oncological diseases, surgery will certainly maintain its elementary role in treatment. However, earlier stages and palliative treatment will be taken over by interventional gastroenterology and radiology. On the other hand, more advanced stages, which are still inoperable today, will benefit from surgery. Surgery of the future will be stimulated by new therapeutic approaches due to local tissue ablation, intraoperative tissue differentiation, new techniques of viscerosynthesis, and improved specimen retrieval. Smart implants and electrical stimulation devices will offer new surgical means to treat functional disorders of the GI tract. A true revolution in surgery will be initiated by cognitive surgery—the comprehensive use of computerized support.

Physiology, lifestyle choices, and maternal nutrition before and during pregnancy have long been known to mediate fetal growth, development, and future health ( fetal programming of adult disease ). Postnatal environmental cues, including infant nutrition, have also been demonstrated to induce powerful, lasting programming effects on growth trajectories, body composition, tissue differentiation, and functional development, as well as long-term health, performance, and disease risks until old age. Hence, improvements of nutrition and metabolism during the first 1000 days of life, including the 270 days of pregnancy and two times 365 days of first two postnatal years, offer particular opportunities for preventive metabolic programming through dietary intervention because of a high degree of developmental plasticity during this early developmental period. However, preventive opportunities are not strictly limited to this 1000 day window, since there is evidence for lasting programming effects of nutrition, before pregnancy as well as after the age of 2 years.

We compare the techniques such as fractional Fourier transform or multiband OCT we have used to map chromatic dispersion in tissues using OCT dataset.

Infiltrative cardiomyopathies are a heterogenous group of diseases that typically lead to restrictive cardiac dysfunction. Due to similar phenotypes, accurate diagnosis is challenging without invasive endomyocardial biopsy which has historically been considered mandatory. Cardiac magnetic resonance (CMR) has been well established in the diagnostic workup of patients with suspected cardiomyopathies due to its unique capability for tissue differentiation and its unsurpassed accuracy in defining cardiac morphology and function. The increasing variety of CMR techniques has generated both excitement and uncertainty with regard to their potential clinical use and its role vis-a-vis conventional noninvasive imaging techniques. The purpose of this review is to give an overview of established and emerging CMR techniques and typical image characteristics of the most commonly encountered infiltrative cardiomyopathies.

A great deal of evidence suggests that partial weight-bearing exercise plays an important role in bone fracture healing. However, current physiotherapy program tends to follow the "Let's try it and see" strategy due to the lack of a fundamental understanding of in vivo mechanical environment required for the better healing outcomes. The purpose of present study is to develop an innovative framework to predict the healing outcomes as a result of post-surgical physical therapy. The raw acceleration data corresponding to a series of walking tests is firstly captured by ActiGraph accelerometers, and then used as input to theoretically estimate the peak ground reaction force (PGRF) and peak loading rate (PLR). Finally, the healing outcomes as a result of different walking speeds are predicated based on the interfragmentary movement (IFM) measured by using mechanical testing. The results show that PGRF and PLR are important factors for the callus tissue differentiation at the early stage of healing. The developed model could potentially allow the design of effective patient specific post-surgical physical therapy.

This paper describes the bone healing process of fractured long bones such as a tibia applied by composite IM rods using finite element analysis. To simulated tissue differentiation process mechano-regulation theory with a deviatoric strain was implemented and a user’s subroutine programmed by a Python code for an iterative calculation was used. To broadly find the appropriate rod modulus for healing bone fractures, composite IM rods were analyzed considering the stacking sequence. To compare mechanical stimulation at fracture gap, two kinds of initial loading conditions were applied. As a result, it was found that the initial loading condition was the most sensitive factor for the healing performance. In case a composite IM rod made of a plain weave carbon fiber/epoxy (WSN3k) had a stacking sequence of [±45] nT , the healing efficiency was the most effective under a initial load of 10%BW. 초 록 본 논문에서는 복합재료 IM rod가 적용된 골절부의 세포 분화과정을 모사하기 위해 유한요소해석을 실시하였다. 세포의 골화 과정을 해석하기 위해 편향 변형률을 이용한 메카노 규제 이론을 사용하였으며, 반복 계산을 위해 Python 코드를 이용하여 서브루틴을 구현하였다. 치료에 가장 적절한 복합재료 IM rod의 강성을 찾기 위해 직물 탄소섬유/에폭시 복합재료 (WSN3k)의 적층 각도를 바꾸어 해석을 실시하였다. 골절부에 가해지는 기계적 자극에 따른 치료효율을 비교하기 위해 두 가지 초기 하중 조건을 적용하였다. 그 결과 치료효율은 강성의 차이보다 하중에 의해 큰 영향을 받았으며, 초기 하중이 몸무게의 10%이고, 적층순서가 [±45]

Background/purpose: Millimeter-wave reflectometry is a potentially interesting technique to analyze the human skin in vivo in order to determine the water content locally in the skin. Purpose of this work is to investigate the possibility of skin-tissue differentiation. In addition, it addresses the influence of the pressure of the probe on the skin, the influence of an air gap between probe and skin as well as the influence of a bandage between probe and skin. Methodology: Reflection coefficients at various positions on the skin are measured in the 40–60 GHz range and the examined effects are quantified in terms of magnitude and phase of the reflection coefficient. Also, the possibility to perform tissue differentiation is quantified. Results: It is indicated that differentiation of skin tissue can be performed on the basis of the magnitude of the reflection coefficient provided that no air gap exists between probe and skin. The influence of probe pressure can be substantial, in particular for phase measurements. The presence of an air gap between probe and skin reduces the differentiation capability of the considered measurement technique, whereas a bandage between probe and skin did not significantly affect the differentiation power. Conclusion: The results of this work confirm the potential of millimeter-wave reflectometry for determination of the water content in skin tissue which may lead to interesting applications as early detection of skin cancer and through-bandage monitoring of wounds.

Here we present a database, WikiCell, as a portal for a unified view of the human transcriptome. At present, WikiCell consists of Expressed Sequenced Tags (ESTs), and users can access, curate, and submit database data by interactive mode, and also can browse, query, upload, and download sequences. Researchers can utilize the transcriptome model based on a human taxonomy graph. The sequences in each model are sorted by attributes such as physiological and pathological samples. The Genbank EST data format are conserved. Gene information is provided, including housekeeping genes, taxonomy location, and gene ontology (GO) description. We believe that WikiCell provides a useful resource for defining expression pattern and tissue differentiation based on human taxonomy mode. It can be accessed at http://www.wikicell.org/.

Vertebromedullary malformations are a heterogeneous group of anomalies of mesenchymal and neuroectodermal tissue differentiation or closure in the midline of the back. On the basis of an embryological analysis, the authors describe the more common malformations, placing them at different times of onset and describing the pathological features and radiological findings based on the use of the most appropriate imaging techniques. The most common malformations have been divided into dysraphic and nondysraphic types and malformations affecting the vertebral bodies. The most complex malformations are detected during the antenatal period by ultrasound or foetal magnetic resonance imaging (MRI). Conversely, during the postnatal period, when the patient's clinical conditions do not warrant emergency surgical treatment, the disorder can be better defined with a detailed MRI scan of the brain and spinal cord. In less complex dysraphisms, although MRI is the imaging modality of choice, it may be useful to integrate the study with plain radiography (X-ray) and multidetector computed tomography (MDCT) for a better assessment of the skeletal components. In these disorders, the use of imaging is aimed at both identifying malformative defects and postoperative follow-up of more complex forms.

3D cell-culture models have recently garnered great attention because they often promote levels of cell differentiation and tissue organization not possible in conventional 2D culture systems. We review new advances in 3D culture that leverage microfabrication technologies from the microchip industry and microfluidics approaches to create cell-culture microenvironments that both support tissue differentiation and recapitulate the tissue–tissue interfaces, spatiotemporal chemical gradients, and mechanical microenvironments of living organs. These ‘organs-on-chips' permit the study of human physiology in an organ-specific context, enable development of novel in vitro disease models, and could potentially serve as replacements for animals used in drug development and toxin testing.

Progress in MSCT is focused on new applications and software development. A hot topic is multispectral imaging which allows for tissue differentiation using at least two energy-levels. Besides differentiation of calcification and jodine in CT-angiography and oncologic imaging, there is also increasing interest in other application fields. Ultrafast imaging nearly eliminates breathing and pulsation artifacts allowing examination of non-compliant patients without sedation or anesthesia. Perfusion can now be extended to large body regions using large detectors or applying shuffle-techniques. New software developments include iterative reconstruction and organ specific dose modulation allowing for dose reduction and for protection of radiosensitive organs.

Remote laser surgery does not provide haptic feedback to operate layer by layer and preserve vulnerable anatomical structures like nerve tissue or blood vessels. The aim of this study is identification of soft tissue in vivo by diffuse reflectance spectroscopy to set the base for a feedback control system to enhance nerve preservation in oral and maxillofacial laser surgery. Various soft tissues can be identified by diffuse reflectance spectroscopy in vivo . The results may set the base for a feedback system to prevent nerve damage during oral and maxillofacial laser surgery.

A 23-year-old Chinese male patient presented with an extremely rare case of spinal teratoma with neuronal and glial tissue components manifesting as lower back pain and radiating pain to the leg. Subtotal excision of the tumor was conducted. Histological examination revealed a mature teratoma with neuronal and glial tissue components. Initial presentation of spinal teratoma in adulthood is rare. Teratomas show a wide array of organoid tissue differentiation, but neuronal tissue component is uncommon.

In a survey the diagnostic usefulness of standardized echography in orbital disease is demonstrated. Considering differential diagnoses it is stressed that ultrasonically determined location and size of the orbital lesion will not do alone. The main object is to achieve a specific diagnosis by way of tissue differentiation. The method is based on standardized A-scan supplemented by contact B-scan and Doppler sonography. Middle and posterior orbit is examined by transocular techniques. A paraocular approach is used for more anterior lesions. From personal experience from more than 300 orbital tumours examples are forwarded illustrating quantitative echography (internal structure, reflectivity, sound attenuation), topographic echography (borders, shape, location), and kinetic echography (consistency, mobility, vascularity). The combination of all nine criteria gives important guidelines concerning the specific lesions met in the orbit and paraorbital regions. The correlation between acoustic and histopathological features is stressed.

Carcinoma of unknown primary (CUP) is one of the 10 most frequent cancers worldwide. It constitutes 3-5% of all human malignancies. Patients with CUP present with metastases without an established primary site. CUP manifests as an heterogenous group of mainly epithelial cancers recognised by distinct clinicopathological entities. The diagnostic work-up includes extensive histopathology investigations and modern imaging technology. Nevertheless, the primary tumour remains undetected most of the time. Molecular diagnosis with DNA microarrays demonstrates high sensitivity, but its prognostic contribution is still uncertain. Certain clinicopathological CUP entities are considered as favourable sub-sets responding to systemic platinum-based chemotherapy or managed by locoregional treatment. These sub-sets are: the poorly differentiated carcinomas involving the mediastinal-retroperitoneal nodes, peritoneal papillary serous adenocarcinomatosis in females, poorly differentiated neuroendocrine carcinomas, isolated axillary node adenocarcinomas in females or cervical nodal involvement by a squamous cell carcinoma. Patients who belong to the non-favourable sub-sets have a worse prognosis. © 2008 Elsevier Ireland Ltd. All rights reserved. 69 3 271 278

This paper presents the 14th Samuel Haughton lecture delivered on the 26th of January 2008. The lecture began by describing Haughton’s research on animal mechanics. Haughton opposed Charles Darwin’s theory of natural selection using the argument that the skeleton obeys the ‘principle of least action’ and therefore must have been designed with that principle in mind. In the course of his research he dissected many animals, including albatrosses, cassowaries, llamas, tigers, jackals and jaguars. He took anatomical measurements and did calculations to prove that muscle attachment sites were optimally located. The relationship between optimality and evolution continues to be studied. Computer simulations show optimality is difficult to achieve. This is because, even if optimality could be defined, the gene recombinations required to evolve an optimal phenotype may not exist. The drive towards optimality occurs under gravitational forces. Simulations to predict mechano-regulation of tissue differentiation and remodelling have been developed and tested. They have been used to design biomechanically optimized scaffolds for regenerative medicine and to identify the mechanoregularory mechanisms in osteoporosis. It is proposed that an important development in bioengineering will be the discovery of algorithms that can be used for the prediction of mechano-responsiveness in biological tissues.

Measurement-based ultrasonography proved mandatory in ophthalmic diagnostic work. It provides comparable examination conditions and therefore, comparable results, in contrast to simple, empirical ultrasonic examination. Measurement methods which can be easily applied under clinical conditions have been developed for determination of those technical characteristics of the apparatus and transducer probes which proved decisive for the diagnostic results. Some echographic criteria can be additionally or better evaluated using this basis. All echo-amplitude measurements should be related to a well-defined test-reflector echo. In addition to sensitivity and resolution, frequency and frequency spectrum are especially important. Manufacturer's data have proved insufficient up to now, insufficient; even within one manufacturer's series of one equipment or transducer probe type considerable deviations from the declared data have been found. Such deviations may mimick pathologic alterations in the echograms. The size of a lesion area can be better evaluated when using well-defined technical conditions. The echographic presentation of tissue structures in the depth is especially dependent on frequency and on the frequency spectrum. Pathologic alterations of tissues may cause changes in the ultrasound attenuation which results in emphasized or reduced presentation of echoes from normal structures behind the lesion area. Tissue differentiation should be based on additional A-scan echograms. Computerized echogram averaging provides a more reliable evaluation of echo amplitudes and ultrasound attenuation. Use of measurement-based ultrasonography permits to compare measured echo-amplitudes and ultrasound attenuation with the results of other working groups, even if these are based on other equipment and transducers.

Standardized echography is a special method of ultrasonic diagnosis developed for the purpose of ophthalmic tissue differentiation. It is a combination of A-scan 7200 MA (Kretztechnik) and a contact real-time B-scanner (Bronson-Turner). The special design and standardization of A-scan instrumentation and the wide range of application in the diagnosis of intraocular diseases are discussed and representative examples are given to emphasize the clinical significance of this method.

Texture of ultrasound images contain information about the properties of examined tissues. The analysis of statistical properties of backscattered ultrasonic echoes has been recently successfully applied to differentiate healthy breast tissue from the benign and malignant lesions. We propose a novel procedure of tissue characterization based on acquiring backscattered echoes from the heated breast. We have proved that the temperature increase inside the breast modifies the intensity, spectrum of the backscattered signals and the probability density function of envelope samples. We discuss the differences in probability density functions in two types of tissue regions, e.g. cysts and the surrounding glandular tissue regions. Independently, Pennes bioheat equation in heterogeneous breast tissue was used to describe the heating process. We applied the finite element method to solve this equation. Results have been compared with the ultrasonic predictions of the temperature distribution. The results confirm the possibility of distinguishing the differences in thermal and acoustical properties of breast cyst and surrounding glandular tissues.

Background Diced cartilage grafts are important in rhinoplasty for raising the dorsum and eliminating dorsal irregularities. The most common problems with the use of diced cartilage are wrapping and cartilage resorption. Objectives To histopathologically investigate and compare the viability of diced cartilage grafts wrapped with concentrated growth factor, fascia and fenestrated fascia, or blood glue. Methods Cartilage grafts were harvested from the ears of 10 New Zealand White rabbits and diced into 0.5 to 1 mm3 pieces. The grafts were divided into five groups for comparison: (1) bare diced cartilage; (2) diced cartilage wrapped with fascia; (3) diced cartilage wrapped with fenestrated fascia; (4) diced cartilage wrapped with concentrated growth factor (CGF); and (5) diced cartilage wrapped with blood glue. Each of the five grafts was autologously implanted into a subcutaneous pocket in the back of each rabbit. Three months later, the rabbits were sacrificed and the implants were harvested and examined histopathologically. Results Nucleus loss, calcification, inflammation, and giant cell formation differed significantly between the CGF group and both fascia groups. Chondrocyte proliferation was the highest in the CGF group. Nucleus loss rates were similar between the fascia and fenestrated fascia groups. Conclusions Our findings suggest that CGF improves the viability of diced cartilage grafts, while fascia hampers it. Punching holes in the fascia does not improve diced cartilage graft viability and neither does blood glue wrapping. © copyright Crown 2016.

Mandibular symphyseal distraction osteogenesis is a common clinical procedure to modify the geometrical shape of the mandible for correcting problems of dental overcrowding and arch shrinkage. In spite of consolidated clinical use, questions remain concerning the optimal latency period and the influence of mastication loading on osteogenesis within the callus prior to the first distraction of the mandible. This work utilized a mechano-regulation model to assess bone regeneration within the callus of an osteotomized mandible. A 3D model of the mandible was reconstructed from CT scan data and meshed using poroelastic finite elements (FE). The stimulus regulating tissue differentiation within the callus was hypothesized to be a function of the strain and fluid flow computed by the FE model. This model was then used to analyse tissue differentiation during a 15-day latency period, defined as the time between the day of the osteotomy and the day when the first distraction is given to the device. The following predictions are made: (1) the mastication forces generated during the latency period support osteogenesis in certain regions of the callus, and that during the latency period the percentage of progenitor cells differentiating into osteoblasts increases; (2) reducing the mastication load by 70% during the latency period increases the number of progenitor cells differentiating into osteoblasts; (3) the stiffness of new tissue increases at a slower rate on the side of bone callus next to the occlusion of the mandibular ramus which could cause asymmetries in the bone tissue formation with respect to the middle sagittal plane. Although the model predicts that the mastication loading generates such asymmetries, their effects on the spatial distribution of callus mechanical properties are insignificant for typical latency periods used clinically. It is also predicted that a latency period of longer than a week will increase the risk of premature bone union across the callus.