In-vivo Procedure Research Articles

A comprehensive review on in-vitro methods for anti- microbial activity

Microbes, also referred to as microscopic creatures because of their minuscule size and invisibility to human sight, are single-celled microorganisms. The first microorganism was discovered between 1665 and 1683 by Robert Hooke and Antoni van Leuwenhoek. There are two categories of techniques for examining microbial activity. methods used in vitro and in vivo. Experiments and tests carried out in a laboratory setting, typically without the presence of a living organism, are referred to as in vitro methods. By creating microbial cultures, cell lines, cell cultures, etc., we may do in vitro experiments. Scientists can study biological processes, assess the effects of medications, and understand systems without having to deal with the complexities of a whole organism by employing in vitro techniques. Growing cells outside of the body in a controlled setting for a range of studies is known as cell culture. Tissues are grown and kept in a lab setting for tissue culture. It is essential to research creating anti-infection therapies. To evaluate a substance's antibacterial activity, in vitro methods such as the brothdilution method and discdiffusion method are commonly used. There are different methods available for the testing of antimicrobial activity and the methods are the agar disk diffusion method, Agar well diffusion method, cross streak method, Bioautography, dilution method, Time kill test, ATP bioluminescence etc. Techniques for determining novel antimicrobial agents and testing for antibiotic susceptibility have been employed. Compared to in-vivo procedures, in vitro methods are less costly. To guarantee an accurate experimental approach, these techniques may be the answer.

Real-time placental vessel segmentation in fetoscopic laser surgery for Twin-to-Twin Transfusion Syndrome

Twin-to-Twin Transfusion Syndrome (TTTS) is a rare condition that affects about 15% of monochorionic pregnancies, in which identical twins share a single placenta. Fetoscopic laser photocoagulation (FLP) is the standard treatment for TTTS, which significantly improves the survival of fetuses. The aim of FLP is to identify abnormal connections between blood vessels and to laser ablate them in order to equalize blood supply to both fetuses. However, performing fetoscopic surgery is challenging due to limited visibility, a narrow field of view, and significant variability among patients and domains. In order to enhance the visualization of placental vessels during surgery, we propose TTTSNet, a network architecture designed for real-time and accurate placental vessel segmentation. Our network architecture incorporates a novel channel attention module and multi-scale feature fusion module to precisely segment tiny placental vessels. To address the challenges posed by FLP-specific fiberscope and amniotic sac-based artifacts, we employed novel data augmentation techniques. These techniques simulate various artifacts, including laser pointer, amniotic sac particles, and structural and optical fiber artifacts. By incorporating these simulated artifacts during training, our network architecture demonstrated robust generalizability. We trained TTTSNet on a publicly available dataset of 2060 video frames from 18 independent fetoscopic procedures and evaluated it on a multi-center external dataset of 24 in-vivo procedures with a total of 2348 video frames. Our method achieved significant performance improvements compared to state-of-the-art methods, with a mean Intersection over Union of 78.26% for all placental vessels and 73.35% for a subset of tiny placental vessels. Moreover, our method achieved 172 and 152 frames per second on an A100 GPU, and Clara AGX, respectively. This potentially opens the door to real-time application during surgical procedures. The code is publicly available at https://github.com/SanoScience/TTTSNet.

Metastasis diagnosis using attenuated total reflection-Fourier transform infra-red (ATR-FTIR) spectroscopy.

The suitability of Fourier transform infrared spectroscopy as a metastasis prognostic tool has not been reported for some cancer types. Our main aim was to show spectroscopic differences between live un-preprocessed cancer cells of different metastatic levels. Spectra of four cancer cell pairs, including colon cancer (SW480, SW620); human melanoma (WM115, WM266.4); murine melanoma (B16F01, B16F10); and breast cancer (MCF7, MDA-MB-231); each pair having the same genetic background, but different metastatic level were analyzed in the regions 1400-1700 cm-1 and 3100-3500 cm-1 using Principal Component Analysis, curve fitting, multifractal dimension and receiver operating characteristic (ROC) curves. The results show spectral markers I1540/I1473, I1652/I1473, [Formula: see text], and multifractal dimension of the spectral images are significantly different for the cells based on their metastatic levels. ROC curve analysis showed good diagnostic performance of the spectral markers in separating cells based on metastatic degree, with areas under the ROC curves having 95% confidence interval lower limits greater than 0.5 for most instances. These spectral features can be important in predicting the probability of metastasis in primary tumors, providing useful guidance for treatment planning. Our markers are effective in differentiating metastatic levels without sample fixation or drying and therefore could be compactible for future use in in-vivo procedures involving spectroscopic cancer diagnosis.

Poke And Delayed Drink Intertemporal Choice Task (POKE-ADDICT): An open-source behavioral apparatus for intertemporal choice testing in rodents.

Advancements in neuroscience research present opportunities and challenges, requiring substantial resources and funding. To address this, we describe here "Poke And Delayed Drink Intertemporal Choice Task (POKE-ADDICT)", an open-source, versatile, and cost-effective apparatus for intertemporal choice testing in rodents. This allows quantification of delay discounting (DD), a cross-species phenomenon observed in decision making which provides valuable insights into higher-order cognitive functioning. In DD, the subjective value of a delayed reward is reduced as a function of the delay for its receipt. Using our apparatus, we implemented an effective intertemporal choice paradigm for the quantification of DD based on an adjusting delayed amount (ADA) algorithm using mango juice as a reward. Our paradigm requires limited training, a few 3D-printed parts and inexpensive electrical components, including a Raspberry Pi control unit. Furthermore, it is compatible with several invivo procedures and the use of nose pokes instead of levers allows for faster task learning. Besides the main application described here, the apparatus can be further extended to implement other behavioral tests and protocols, including standard operant conditioning. In conclusion, we describe a versatile and cost-effective design based on Raspberry Pi that can support research in animal behavior, decision making and, more specifically, delay discounting.

Loss of hypothalamic Furin affects POMC to proACTH cleavage and feeding behavior in high-fat diet-fed mice

ObjectiveThe hypothalamus regulates feeding and glucose homeostasis through the balanced action of different neuropeptides, which are cleaved and activated by the proprotein convertases PC1/3 and PC2. However, the recent association of polymorphisms in the proprotein convertase FURIN with type 2 diabetes, metabolic syndrome, and obesity, prompted us to investigate the role of FURIN in hypothalamic neurons controlling glucose and feeding. MethodsPOMC-Cre+/− mice were bred with Furinfl/fl mice to generate conditional knockout mice with Furin-deletion in neurons expressing proopiomelanocortin (POMCFurKO), and Furinfl/fl mice were used as controls. POMCFurKO and controls were periodically monitored on both normal chow diet and high fat diet (HFD) for body weight and glucose tolerance by established in-vivo procedures. Food intake was measured in HFD-fed FurKO and controls. Hypothalamic Pomc mRNA was measured by RT-qPCR. ELISAs quantified POMC protein and resulting peptides in the hypothalamic extracts of POMCFurKO mice and controls. The in-vitro processing of POMC was studied by biochemical techniques in HEK293T and CHO cell lines lacking FURIN. ResultsIn control mice, Furin mRNA levels were significantly upregulated on HFD feeding, suggesting an increased demand for FURIN activity in obesogenic conditions. Under these conditions, the POMCFurKO mice were hyperphagic and had increased body weight compared to Furinfl/fl mice. Moreover, protein levels of POMC were elevated and ACTH concentrations markedly reduced. Also, the ratio of α-MSH/POMC was decreased in POMCFurKO mice compared to controls. This indicates that POMC processing was significantly reduced in the hypothalami of POMCFurKO mice, highlighting for the first time the involvement of FURIN in the cleavage of POMC. Importantly, we found that in vitro, the first stage in processing where POMC is cleaved into proACTH was achieved by FURIN but not by PC1/3 or the other proprotein convertases in cell lines lacking a regulated secretory pathway. ConclusionsThese results suggest that FURIN processes POMC into proACTH before sorting into the regulated secretory pathway, challenging the dogma that PC1/3 and PC2 are the only convertases responsible for POMC cleavage. Furthermore, its deletion affects feeding behaviors under obesogenic conditions.

The Effects of Remote Instructions, Rehearsal, and Feedback on Preference Assessment Implementation

ABSTRACT The use of telehealth has seen recent growth due to the coronavirus disease, resulting in large-scale service delivery changes, which may also necessitate a shift in staff training and performance management procedures. One effective in-vivo procedure is the delivery of performance feedback. There are many characteristics that affect the efficacy of performance feedback (e.g., immediacy). Thus, it may be important to understand how remote technology also affects performance feedback. We evaluated the effects of remote feedback on the accuracy of preference assessment implementation using telehealth-based coaching with three individuals following a history of written instructions and remote rehearsal. Remote feedback was effective for all three participants. Additionally, skills maintained at high levels 1-week post-training and occurred in the presence of a novel confederate and novel stimuli for two of the three participants.

Automatic image and text-based description for colorectal polyps using BASIC classification

Colorectal polyps (CRP) are precursor lesions of colorectal cancer (CRC). Correct identification of CRPs during in-vivo colonoscopy is supported by the endoscopist's expertise and medical classification models. A recent developed classification model is the Blue light imaging Adenoma Serrated International Classification (BASIC) which describes the differences between non-neoplastic and neoplastic lesions acquired with blue light imaging (BLI). Computer-aided detection (CADe) and diagnosis (CADx) systems are efficient at visually assisting with medical decisions but fall short at translating decisions into relevant clinical information. The communication between machine and medical expert is of crucial importance to improve diagnosis of CRP during in-vivo procedures. In this work, the combination of a polyp image classification model and a language model is proposed to develop a CADx system that automatically generates text comparable to the human language employed by endoscopists. The developed system generates equivalent sentences as the human-reference and describes CRP images acquired with white light (WL), blue light imaging (BLI) and linked color imaging (LCI). An image feature encoder and a BERT module are employed to build the AI model and an external test set is used to evaluate the results and compute the linguistic metrics. The experimental results show the construction of complete sentences with an established metric scores of BLEU-1 = 0.67, ROUGE-L = 0.83 and METEOR = 0.50. The developed CADx system for automatic CRP image captioning facilitates future advances towards automatic reporting and may help reduce time-consuming histology assessment.

A liquid breakdown driven non-invasive microjet injection system

The purpose of this study was to develop a microjet having fully skin-penetrable jet speed, moderately small volume, and highly repeatable injection, and eventually providing a device with medical efficacy for less tissue destruction and pain. The injector allows a small volume of drug stream (0.1–1.7 µL) to flow out at a frequency of ~16 Hz, and employs two different sources of energy, namely electrical and optical, which are converted into kinetic energy of the penetrating drug solution using liquid breakdown (dielectric or laser-induced). The medical efficacy of the microjet injection was evaluated through ex-vivo and in-vivo procedures in a mouse model. Both sources of liquid breakdown generate a skin-penetrable jet speed of 200–330 m/s. These fast and repetitive jets in a small volume pass through the epidermis to exert their efficacy. The driving pressure provided by dielectric breakdown showed an extensive increase per input energy increase, which is deemed appropriate for deep skin penetration. In contrast, the laser-induced breakdown exhibited a saturation in jet speed with increasing input energy, which is indicative of a low energy conversion efficiency. The results are promising for medical procedures that require uniform drug injection over a large area, and small dosage control during intradermal procedures.

Experimental model of occluded biliary metal stent recanalization using irreversible electroporation via a tubular catheter

Purpose To demonstrate the feasibility of irreversible electroporation (IRE) for treating biliary metal stent occlusion in an experimental liver model. Methods and materials IRE was performed using an expandable tubular IRE-catheter placed in nitinol stents in the porcine liver. A 3-electrode IRE-catheter was connected to an IRE-generator and one hundred 100μs pulses of constant voltage (300, 650, 1000, and 1300 V) were applied. Stent occlusion was simulated by insertion of liver tissue both ex vivo (n = 94) and in vivo in 3 pigs (n = 14). Three scenarios of the relationship between the stent, electrodes, and inserted tissue (double contact, single contact, and stent mesh contact) were studied. Electric current was measured and resistance and power calculated. Pigs were sacrificed 72 h post-procedure. Harvested samples (14 experimental, 13 controls) underwent histopathological analysis. Results IRE application was feasible at 300 and 650 V for the single and double contact setup in both ex vivo and in vivo studies. Significant differences in calculated resistance between double contact and single contact settings were observed (ex-vivo p ˂ 0.0001, in-vivo p = 0.02; Mann–Whitney). A mild temperature increase of the surrounding liver parenchyma was noted with increasing voltage (0.9–5.9 °C for 300–1000 V). The extent of necrotic changes in experimental samples in vivo correlated with the measured electric current (r 2 = 0.39, p = 0.01). No complications were observed during or after the in-vivo procedure. Conclusion Endoluminal IRE using an expandable tubular catheter in simulated metal stent occlusion is feasible. The relationship of active catheter electrodes to stent ingrowth tissue can be estimated based on resistance values.

Prospective, Randomized Assessment of Transfer of Training (ToT) and Transfer Effectiveness Ratio (TER) of Virtual Reality Simulation Training for Laparoscopic Skill Acquisition

We assessed the effectiveness of ToT from VR laparoscopic simulation training in 2 studies. In a second study, we also assessed the TER. ToT is a detectable performance improvement between equivalent groups, and TER is the observed percentage performance differences between 2 matched groups carrying out the same task but with 1 group pretrained on VR simulation. Concordance between simulated and in-vivo procedure performance was also assessed. Prospective, randomized, and blinded. In Study 1, experienced laparoscopic surgeons (n = 195) and in Study 2 laparoscopic novices (n = 30) were randomized to either train on VR simulation before completing an equivalent real-world task or complete the real-world task only. Experienced laparoscopic surgeons and novices who trained on the simulator performed significantly better than their controls, thus demonstrating ToT. Their performance showed a TER between 7% and 42% from the virtual to the real tasks. Simulation training impacted most on procedural error reduction in both studies (32-42%). The correlation observed between the VR and real-world task performance was r > 0·96 (Study 2). VR simulation training offers a powerful and effective platform for training safer skills.

VOICE ACTIVATION VISUALIZATION FOR ECHOCARDIOGRAPH AND 3D ANGIOGRAPHIC IMAGES IN SURGERY

In some cases, surgeons need to navigate through th e computer system for reconfirmation patients’ deta ils and unfortunately surgeons unable to manage both co mputer system and operation at the same time. In th is paper we propose a solution for this problem especi ally designed for heart surgeon, by introducing voi ce activation system with 3D visualization of Angiogra phic images, 2D visualization of Echocardiography processed video and selected patient’s details. In this study, the processing, approximation of the 3D angiography and the visualization of the 2D echocar diography video with voice recognition control are the most challenging work. The work involve with predicting 3D coronary three from 2D angiography image and also image enhancement which utilize the median filtering, morphological opening and contrast improvement and heart boundaries detection. With 3D reconstruction of 2D angiography images, the syste m was able to display 3D coronary tree, with voice ac tivation. The system was able to rotate, zoom in an d out the 3D image, the 2D echocardiography video and display patient’s information that needed by the surge on while doing heart surgery. Development of this syst em is useful for surgeons, where they can navigate the system using voice commands instead of keyboard and mouse. Medical practitioners also can facilitate more the angiogram and echocardiograph images. With this system, it can help and ease the work of surgeons in analyzing and processing the medical images especially in-vivo procedure.

Short wheat challenge is a reproducible in-vivo assay to detect immune response to gluten

It has been reported that interferon (IFN)-γ-secreting T cells reactive to gluten can be detected in the peripheral blood of individuals with treated coeliac disease (CD) after a short consumption of wheat-containing food. By contrast, very little is known about the reproducibility of this in-vivo procedure in the same patient cohort which underwent two, or more, gluten consumptions. Fourteen coeliac patients in remission consumed wheat bread for 3 days; 13 underwent a second gluten challenge after a wash-out of 3-10 months on a strict gluten-free diet. Immune reactivity to gluten was analysed in peripheral blood by detecting IFN-γ before and 6 days after commencing a gluten diet. Gliadin-specific IFN-γ-secreting CD4(+) T cells increased significantly on day 6 of the first challenge. These cells resulted as prevalently human leucocyte antigen (HLA)-DQ restricted and with a phenotype of gut homing, as suggested by the expression of β7-integrin. Similarly, reactiveness to gliadin was observed after the second wheat consumption, although with an individual variability of responses at each challenge. Our findings confirmed that the short wheat challenge is a non-invasive approach to investigate the gluten-related immune response in peripheral blood of subjects intolerant to gluten. Furthermore, we demonstrated that the in-vivo procedure can be reproduced in the same subject cohort after a gluten wash-out of at least 3 months. Our study has important implications for the application of this procedure to clinical practice.

Acquisition of the 3D surface of the palate by in-vivo digitization with Wave

An accurate characterization of the morphology of the hard palate is essential for understanding its role in human speech. The position of the tongue is adjusted in the oral cavity, of which the hard palate is a key anatomical structure. Methods for modeling the palate are limited at present. This paper evaluated the use of a thin plate spline (TPS) technique for reconstructing the palate surface from a series of in-vivo tracings obtained with electromagnetic articulography using Wave (NDI). Twenty-four individuals (13 females and 11 males) provided upper dental casts and in-vivo tracings. Models of the palate surfaces were derived from data acquired in-vivo and compared to the scanned casts. The optimal value for the smoothness parameter for the TPS technique, which provided the smallest error of fit between the modeled and scanned surfaces, was determined empirically (the value of 0.05). Significant predictors of the quality of the fit were determined and included the individuals’ palate characteristics such as palate slope and curvature. The tracing protocol composed of four different traces produced the best palate models for the in-vivo procedure. Evidence demonstrated that the TPS procedure as a whole is suitable for modeling the palate surface using a small number of in-vivo tracings.

Clinical appraisal of chronic traumatic encephalopathy

There are currently no consensus-based clinical diagnostic criteria for chronic traumatic encephalopathy (CTE). This review provides an update on recent literature pertaining to clinically relevant procedures that--presently or in the future--may be useful for the in-vivo detection, characterization, and/or prediction of CTE. Preliminary evidence about the clinical manifestations of CTE has been accumulating via post-mortem medical record review and interviews of friends or family members of individuals with neuropathologically documented CTE. This evidence suggests that CTE is manifested clinically by changes in cognition (especially memory and executive functioning, with dementia later in the disease course), mood (especially, depression, apathy, and suicidality), personality and behavior (especially poor impulse control and behavioral disinhibition), and movement (including parkinsonism and signs of motor neuron disease). At the present time, evidence regarding CTE has not been confirmed in a prospective study of a cohort at risk for CTE. On the basis of recent research in the fields of dementia and traumatic brain injury, several in-vivo procedures (including neurological examination, neuropsychological assessment, neuroimaging techniques, and blood and cerebrospinal fluid biomarkers) each have the potential to contribute unique information about the manifestations of CTE, including clinical and preclinical stages. More research is needed to develop a set of consensus diagnostic criteria that provide a reliable and valid indicator of neuropathologically verified CTE. Until such criteria are developed, the clinical assessment of CTE should be informed by modern research that is of relevance to traumatic brain injury and neurodegenerative diseases.

Factors affecting dormancy of <i>Oncocyclus</i> iris seeds

Oncocyclus irises (Iridaceae) are endangered plants in Israel, yet with high potential for cultivation as ornamental flowers. However, their high seed dormancy level prevents fast development of germplasm for horticultural reproduction. In this paper we describe in-vitro and in-vivo germination experiments with seeds of Oncocyclus irises from Israel. We examined the effects of (1) mechanical scarification and different growing media on in-vitro seed germination; and (2) soil type, covering, and water amount on in-vivo germination. Seeds showed high dormancy, as hardly any seed germinated in the first year after sowing, and only in the second growing season the germinating fraction was considerable (up to 37%), still only under high humidity conditions. We also report an effective in-vitro forced germination protocol, which employs seed scarification. Following these results for in-vivo germination, and based on the protocol developed for in-vitro germination, we recommend two methods for artificial seed germination. For fast germination, good results from a modest quantity of seeds can be obtained by an in-vitro forced germination. For mass seed propagation, when time is not a limiting factor, the in-vivo procedure can be used, using an artificial soil seed bank and treating those seeds during (at least) two seasons under shade and continuous watering.

Estimation of temperature distribution with the use of a thermo-camera

Estimation of temperature distribution with the use of a thermo-camera The determination of three-dimensional (3D) temperature distribution within tissue during thermoablation is necessary to estimate procedure efficiency. The use of a thermo-camera combined with finite element modelling is discussed. The temperature distributions in a metal phantom and an animal tissue sample were simulated. In the real experiment, temperatures were measured around the heating probe by a thermo-resistor set and the temperature distributions on samples' surface were acquired by a thermo-camera. The temperatures measured in the experiment were compared with the simulated ones. The differences between the measured and simulated temperatures were lower than 1.3°C and 3.0°C for a metal phantom and tissue sample, respectively. Good agreement was achieved for homogenous material of well-defined parameters. Higher discrepancies for the tissue sample are due to in-homogeneity and to difficulties with describing tissue thermal properties. The proposed method permits the precise prediction of a 3D temperature distribution in in-vitro studies. Potential application for in-vivo procedures requires further investigations.

Prediction of meat quality in live pigs using stress-susceptible and stress-resistant animals

A new in-vivo procedure for predicting the potential meat quality in live pigs was devised using stress-susceptible (halothane positive) and stress-resistant (halothone negative) pigs. The potential meat quality in live pigs was determined using small biopsy samples of M. longissimus dorsi (LD). Meat quality was assessed by the combined measurements of pH and water-holding capacity (WHC) on the 12 000 g supernatant after incubation of 500 mg biopsy LD muscle with an equal volume of 150 m m KCl at 39°C for 45 min. With the LD muscles of halothane positive ( n = 37) and halothane negative (n = 55) pigs, high correlations (r = −0·854) were observed between the supernatant (i.e. fluid) pH and WHC of the biopsy samples, between fluid pH of the biopsy samples and 1-h post-mortem (pH 60) LD muscles (r = 0·951), and between pH 60 and WHC (r = −0·956). The experimental data show that our in-vivo test can differentiate halothane positive from halothane negative pigs and can also predict the potential meat quality in live pigs. The test could be applied to select pigs with differences in WHC to improve meat quality.