Noninvasive Studies Research Articles

IVF culture media refresh in a reduced volume on day4 aimed at improving non-invasive embryo selection does not affect embryo competence: a prospective analysis of 2605 embryos

Background and Aim: Omic analyses on spent-culture-media are emerging as non-invasive schemes for embryo selection. Media refresh and reduced culture volume are critical to improve their specificity and sensitivity. However, limited evidence exists to support embryo culture in reduced volumes and some authors claimed this practice might influence developmental and reproductive potential altering the concentration of autocrine factors and/or of potentially-toxic metabolites. It is therefore critical to outline suitable protocols to preserve embryonic competence while improving non-invasive embryo-selection strategies.Methods: Between March2018 and December2019, 1357 oocyte-pick-ups for PGT-A were conducted. All couples could choose to participate to a pilot non-invasive PGT-A study (ClinicalTrials.gov:NCT03520933) whose design involved culture media refresh the morning of day4 from 30 µl single drops of continuous-single-culture-media (CSCM) to 10 µl for ≥40hr until blastocyst full-expansion or developmental arrest. If not consenting to the study, no refresh was performed, and embryo culture was concluded in 30 µl of CSCM. ICSI, blastocyst-culture under mineral-oil (5%O2/6%CO2), grading according to Capalbo et al (2014), trophectoderm-biopsy, NGS-based analysis and vitrified-warmed euploid single-embryo-transfer (SET) were performed. Overall, 389 and 151 cycles met the inclusion criteria (maternal age <44yr, own gametes, ejaculated sperm, no severe-oligoasthenoteratozoospermia) in the control and study group. Only viable embryos in day4 were included: 1873 and 732 in the control and study group. The primary outcome was the blastulation-rate per day4 viable embryos. Secondary outcomes were blastocyst quality, euploidy, clinical-pregnancy-, miscarriage- and sustained-implantation-rate per euploid single-embryo-transfer. All transfers performed up to August 2021, and issuing from these cycles, were included (N=378 and 137, respectively). Fisher's exact tests and logistic-regression-analyses adjusted for confounders were conducted.Results: The blastulation-rate per day4 viable embryo was similar in the control and study group (n=915/1873,49% versus 365/732, 50%). Blastocyst quality was also similar (excellent: 47% versus 50%, good:20% versus 15%, average:12% versus 14%, poor: 21% versus 21%). The euploidy-rates were 36% (n=330/915) and 37% (n=136/365). No difference was reported in clinical-pregnancy- (n=232/378,61% versus n=83/137,61%), miscarriage- (n=34/220,15% versus n=10/76,13%) and sustained-implantation-rates (n=186/378,49% versus n=66/137,48%). Media refresh in 10 µl for ≥40hr from day4 did not impact blastocyst development (multivariate-OR 0.99,95%CI:0.83-1.2, p=0.97) and sustained-implantation (multivariate-OR 0.96,95%CI:0.64-1.42, p=0.83).Conclusions: This study supports single embryo culture in a reduced volume of media from day4. This strategy is critical to minimize the risk for external contamination and to increase the concentration of embryonic-molecules (cell-free-DNA, mtDNA, miRNAs, metabolites) for non-invasive embryo-selection purposes. Background and Aim: Omic analyses on spent-culture-media are emerging as non-invasive schemes for embryo selection. Media refresh and reduced culture volume are critical to improve their specificity and sensitivity. However, limited evidence exists to support embryo culture in reduced volumes and some authors claimed this practice might influence developmental and reproductive potential altering the concentration of autocrine factors and/or of potentially-toxic metabolites. It is therefore critical to outline suitable protocols to preserve embryonic competence while improving non-invasive embryo-selection strategies. Methods: Between March2018 and December2019, 1357 oocyte-pick-ups for PGT-A were conducted. All couples could choose to participate to a pilot non-invasive PGT-A study (ClinicalTrials.gov:NCT03520933) whose design involved culture media refresh the morning of day4 from 30 µl single drops of continuous-single-culture-media (CSCM) to 10 µl for ≥40hr until blastocyst full-expansion or developmental arrest. If not consenting to the study, no refresh was performed, and embryo culture was concluded in 30 µl of CSCM. ICSI, blastocyst-culture under mineral-oil (5%O2/6%CO2), grading according to Capalbo et al (2014), trophectoderm-biopsy, NGS-based analysis and vitrified-warmed euploid single-embryo-transfer (SET) were performed. Overall, 389 and 151 cycles met the inclusion criteria (maternal age <44yr, own gametes, ejaculated sperm, no severe-oligoasthenoteratozoospermia) in the control and study group. Only viable embryos in day4 were included: 1873 and 732 in the control and study group. The primary outcome was the blastulation-rate per day4 viable embryos. Secondary outcomes were blastocyst quality, euploidy, clinical-pregnancy-, miscarriage- and sustained-implantation-rate per euploid single-embryo-transfer. All transfers performed up to August 2021, and issuing from these cycles, were included (N=378 and 137, respectively). Fisher's exact tests and logistic-regression-analyses adjusted for confounders were conducted. Results: The blastulation-rate per day4 viable embryo was similar in the control and study group (n=915/1873,49% versus 365/732, 50%). Blastocyst quality was also similar (excellent: 47% versus 50%, good:20% versus 15%, average:12% versus 14%, poor: 21% versus 21%). The euploidy-rates were 36% (n=330/915) and 37% (n=136/365). No difference was reported in clinical-pregnancy- (n=232/378,61% versus n=83/137,61%), miscarriage- (n=34/220,15% versus n=10/76,13%) and sustained-implantation-rates (n=186/378,49% versus n=66/137,48%). Media refresh in 10 µl for ≥40hr from day4 did not impact blastocyst development (multivariate-OR 0.99,95%CI:0.83-1.2, p=0.97) and sustained-implantation (multivariate-OR 0.96,95%CI:0.64-1.42, p=0.83). Conclusions: This study supports single embryo culture in a reduced volume of media from day4. This strategy is critical to minimize the risk for external contamination and to increase the concentration of embryonic-molecules (cell-free-DNA, mtDNA, miRNAs, metabolites) for non-invasive embryo-selection purposes.

S2601 Gastroepiploic Pseudoaneurysm: A Shocking Complication of PEG Tube Placement

Introduction: Percutaneous gastrostomy (PEG) tubes are commonly used for enteric feeds and medication administration. While considered safe and routine, PEG tube placement is not without its complications. Here we present a rare case of hemorrhagic shock secondary to traumatic pseudoaneurysm formation after PEG tube placement. Case Description/Methods: A 52-year-old male with atrial fibrillation on apixaban and a recent stroke with PEG tube placement 1 month prior to arrival presented to the hospital with multiple episodes of hematemesis. CT angiography of the abdomen was unremarkable and negative for signs of active bleeding. Antiplatelets were held and anticoagulation was reversed with prothrombin complex concentrate. Esophagogastroduodenoscopy showed signs of erosive esophagitis with proper PEG tube placement but without signs of active bleeding. Hematemesis re-occurred less than 24 hours after anticoagulation was resumed, with subsequent development of hemorrhagic shock. Visceral arteriogram revealed a right gastroepiploic artery pseudoaneurysm, which likely developed from trauma during recent PEG placement. The patient stabilized after coil embolization and blood transfusion. He was then safely resumed on anticoagulation without further bleeding. Discussion: GI bleeding associated with PEG placement occurs in 0.6-1.2% of cases, and usually occurs at the gastrostomy tract or from gastric ulceration. Bleeding related to pseudoaneurysm formation is exceedingly rare with only a handful of case reports documenting such occurrence. While contrast enhanced imaging may aid in the diagnosis, small pseudoaneurysms may not be detected with noninvasive angiographic studies (as was the case here). Given this potentially life-threatening complication, clinicians must consider pseudoaneurysm formation as part of their differential for GI bleed after recent PEG placement especially if endoscopic evaluation is unrevealing.

Polychromic light source for the realization of multispectral processing method of skin malignant lesions images

When diagnosing oncological skin diseases, the problem of untimely detection of pathologies remains relevant. Modern diagnostic methods have a number of disadvantages associated with the limited capabilities of human vision, high requirements for non-invasive studies and digital representation of the results obtained for their transmission over communication channels. The most important tasks of early binary diagnostics of skin neoplasms can be solved using bioradiophotonics methods. The paper considers the author’s multispectral method for processing images of skin areas using a new specialized polychrome light source with software control of the radiation wavelength. The principle of operation of such a source is analyzed and the use of a set of LEDs with a special arrangement is justified which makes it possible to direct a beam of light of any wavelength in one direction. The choice of the wavelength ranges used for LEDs is confirmed, the first version of the layout of such a light source is described, and its optical and structural diagrams are given. It is shown that the optimal way of the wavelength programmable control is its coarse tuning by switching LEDs and fine tuning by acousto-optic tunable filters installed at the source output. A number of test images of a pigment spot on the skin with a size of 40 × 30 mm with wavelengths ranging from near ultraviolet to near infrared ranges using a black and white camera are presented. With digital processing, received monochromatic images, histogram equalization and median filtering of images were carried out to expand the dynamic range of brightness levels and minimize distortion caused by the unevenness of the skin area under study and the presence of shadow illumination. Graphs of the amplitude intensity distribution in the original and filtered images are obtained for the selected wavelengths of the LEDs. It is shown that the presence of a skin neoplasm can be judged by the dips in the light intensity distribution curve. The radial arrangement of LEDs on the board is justified to minimize shadow illumination when illuminating the skin. The conducted studies of multispectral image processing using a realized polychrome light source contribute to the development of new methods for the early diagnosis of skin neoplasms based on photonics and optoelectronics and can find practical application in medical technologies.

Optimization of the Antenna Unit of the Superconducting Magnetometer: Research of Weak Magnetic Signals

Introduction. The article describes the optimization of the superconducting antenna design and balancing method of the superconducting antenna of magnetometer. This magnetometer is designed to study the magnetic properties of materials, as well as non-invasive study of the distribution of magnetic particles in organs of small laboratory animals, when toxic particles or drugs are introduced into the animal's body. The superconducting antenna of the magnetometer is a second-order axial gradiometer and is a part of the flux transformer of the SQUID sensor. For stable operation within the dynamic range of the magnetometer, the antenna must have a balance degree of at least 1/1000. Traditionally, it is balanced in a separate tuning module (Helmholtz coils), which creates a homogeneous magnetic field with a high degree of uniformity. The purpose. The problem is that the subsequent displacement of the SQUID magnetometer unit into the measuring complex, even within the laboratory, reduces the degree of balance of the magnetometer due to objects that create a strong gradient magnetic field, which negatively affects the measurements. Results. As a solution of this problem, the some approaches are described in the article. In order to increase the uniformity of the field inside the solenoid and eliminate field distortions at its edges, the using of solenoid with a special arrangement of turns to balance the antenna directly at the measurement site was proposed. The balancing elements for the horizontal components of the magnetic field were eliminated. Also the antenna balancing element in the form of a ring along the vertical component of the magnetic field, which does not violate the symmetry of the antenna was applied. Conclusions. Using this approach, it is possible to optimize the design of the antenna unit and the balancing process of the magnetometer antenna with a sufficient degree of balance in the vertical component directly in the geometric center of the measuring system, which reduced the time of preparing the system for work and improved the metrological indicators of the system. Keywords: superconductivity, SQUID-magnetometry, axial gradiometer, antenna balance, optimization.

PH-responsive sustained delivery of doxorubicin using aminated and PEGylated mesoporous silica nanoparticles leads to enhanced antitumor efficacy in pre-clinical orthotopic breast cancer model

Doxorubicin (Dox) is one of the chemotherapeutic drugs used in the treatment of breast cancers. However, doxorubicin-mediated toxicity limits its use in clinics. In this study, mesoporous silica nanoparticles (MSN) were prepared by the sol-gel method. Further, it was aminated and then Dox was loaded into its pores. Subsequently, Dox-loaded MSN was coated with polyethylene glycol (PEG) and further attached with targeting moieties, such as folic acid (FA) or hyaluronic acid (HA). TEM images reveal that the average diameter of MSN is 90 nm, which increases to 107 nm after coating PEG over the surface of MSN. At pH 5.5 the drug gets slowly released over a time of 120 h. In vitro cytotoxicity demonstrates that free Dox has higher cytotoxicity than Dox-loaded nanoparticles. However, a non-invasive molecular imaging-guided preclinical study, using the 4T1 orthotopic breast cancer model demonstrates that Dox-loaded MSN formulations inhibited tumor growth to a significant level. In fact, free Dox-treated mice died after only three doses, due to its severe toxicity, which is also evident from the low spleen index, biochemical, and histopathology analysis. Further, it is observed from the survival curve that, MSN–NH2–Dox-PEG-FA and MSN–NH2–Dox-PEG-HA extend the survival of the mice up to 35 days with reduced side effects. Therefore, targeted PEGylated MSN can be used as a carrier to deliver Dox to cancer patients and possibly reduce the side effects.

Indentation of a pressurized silicon stomach model – A non-invasive study of gastric wall stiffness and pressurized gastric content stiffness

Background and aimsEvaluation of gastric wall stiffness and intragastric pressure is essential for detailed assessments of gastric accommodation. However, non-invasive assessments are needed for large scale clinical studies and none of the existing methods takes abdominal wall effect into the calculation. This study aimed to assess gastric wall stiffness and gastric content stiffness as a proxy for intragastric pressure using novel mechanical modeling and non-invasive indentation tests on a silicon stomach model. MethodsA silicon stomach model (scaling 1:1 with the human stomach) was indented using a pressure algometer at intragastric pressures from 0 to 0.8 kPa. Wall thicknesses and luminal cross-sectional areas along the stomach were measured with ultrasound images. The gastric wall stiffness was compared between measurements from tensile tests on strips cut from the silicon stomach and estimations from a shell indentation model. The pressurized gastric content stiffness was predicted from a bonded two-layer axisymmetric half-space indentation model. ResultsThe gastric wall stiffness estimated from the shell indentation model showed no difference to measurements from the mechanical tests on the cutting strips (p = 0.14). The predicted gastric content stiffness was strongly associated with the intragastric pressure (r > 0.83, p < 0.001). ConclusionsThe mechanical model developed in this study can simultaneously predict the gastric wall stiffness and the pressurized gastric content stiffness. In future studies, the method can be applied to reveal intragastric pressure conditions non-invasively via the pressurized gastric content stiffness during gastric accommodation and emptying such as with magnetic resonance imaging.

Distinct interacting cortical networks for stimulus-response and repetition-suppression

Non-invasive studies consider the initial neural stimulus response (SR) and repetition suppression (RS) – the decreased response to repeated sensory stimuli – as engaging the same neurons. That is, RS is a suppression of the SR. We challenge this conjecture using electrocorticographic (ECoG) recordings with high spatial resolution in ten patients listening to task-irrelevant trains of auditory stimuli. SR and RS were indexed by high-frequency activity (HFA) across temporal, parietal, and frontal cortices. HFASR and HFARS were temporally and spatially distinct, with HFARS emerging later than HFASR and showing only a limited spatial intersection with HFASR: most HFASR sites did not demonstrate HFARS, and HFARS was found where no HFASR could be recorded. β activity was enhanced in HFARS compared to HFASR cortical sites. θ activity was enhanced in HFASR compared to HFARS sites. Furthermore, HFASR sites propagated information to HFARS sites via transient θ:β phase-phase coupling. In contrast to predictive coding (PC) accounts our results indicate that HFASR and HFARS are functionally linked but have minimal spatial overlap. HFASR might enable stable and rapid perception of environmental stimuli across extended temporal intervals. In contrast HFARS might support efficient generation of an internal model based on stimulus history.

Assessing Non-invasive Studies to Evaluate Resynchronization Pacing Effectiveness in the Young.

Appropriate non-invasive assessments (ECHO/ECG) of cardiac resynchronization pacing therapy (CRT) among younger patients (pts) with/without (w/wo) congenital heart disease (CHD) are not established. Ejection fraction (EF) and QRS can be unreliable due to anatomy, surgical repairs, and pre-existing pacemakers (PM). This study correlates updated non-invasive studies, including newer strain values, with clinical and invasive hemodynamic assessments of CRT response in the young. Sixteen pts (mean age 18.5 ± 6years, 10/16 with pre-existing pacemakers) underwent CRT for heart failure (NYHA II-III). CHD included septal defects and Tetralogy of Fallot. Assessment of CRT efficacy was based on clinical findings, direct catheterization studies [pressures, contractility indices (dP/dt-max)], ECG changes, and ECHO studies [including updated global (GLS), left atrial strain (LAS), and sphericity indices] pre- and at 1-month and 1-year post-CRT. After 1year following CRT, all pts improved (II-III to I-II) in clinical NYHA status. Contractility (dP/dt) increased (932 ± 351 vs 561 ± 178.7mmHg-sec [p = 0.001]). QRS duration shortened only among pts with pre-existing PM (160 ± 25 vs 134 ± 25ms [p = 0.02]). Standard ECHO parameters, including chamber dimensions and EF, showed no appreciable changes from pre-CRT values. However, endocardial GLS [(-6.4 vs. -9.6%) p = 0.0003] and LAS [(-5.8 vs -9.3%) p = 0.02] values significantly improved. Although CRT is applicable to younger pts, accurate non-invasive evaluations of response are lacking. This study establishes that newer strain values better correlate with clinical and hemodynamic changes over other parameters and offer more appropriate assessments of CRT response.

Optical imaging and spectroscopy for the study of the human brain: status report.

.This report is the second part of a comprehensive two-part series aimed at reviewing an extensive and diverse toolkit of novel methods to explore brain health and function. While the first report focused on neurophotonic tools mostly applicable to animal studies, here, we highlight optical spectroscopy and imaging methods relevant to noninvasive human brain studies. We outline current state-of-the-art technologies and software advances, explore the most recent impact of these technologies on neuroscience and clinical applications, identify the areas where innovation is needed, and provide an outlook for the future directions.

Peculiarities of surgical treatment of atrial macro reentry tachyarrhythmia in elderly patients with implanted pacemaker

Atrial macro reentry tachycardias are the most common tachyarrhythmias in the structure of cardiac arrhythmias in the elderly. Catheter ablations are the gold standard for the treatment of atrial macro reentry arrhythmias, but in the elderly group, the risks of complex ablations often outweigh the benefits. Aim: to determine the optimal volume of catheter ablation in atrial tachyarrhythmia using an implanted pacemaker in elderly patients. Materials and methods. The work is based on a retrospective analysis of the results of surgical treatment of (n = 45) elderly patients (75–90 years) with atrial macro reentry tachycardia, who were previously identified as an artificial pacemaker at the National M. Amosov Institute of Cardiovascular Surgery Affiliated to National Academy of Medical Sciences of Ukraine. Patients were divided into 3 groups depending on the response of the reentry tachycardia to electrical pacing (assessed by the difference between postpacing interval (PPI) and tachycardia cycle lens (CL): group І – PPI-CL 20–40 ms; group ІІ – PPI–CL 20–40 ms; group ІІІ – PPI-CL 60 ms and more. Results. In the group I (n = 20) in 100 % of the patients isthmus-dependent reentry tachyarrhythmia was diagnosed and cava-tricuspid isthmus was ablated. In the group ІІ (n = 12) 4 (33 %) patients were diagnosed with reentry tachycardia around the right pulmonary veins, in 8 (67 %) patients – reentrant tachycardia around the mitral valve. In the group ІІІ (n = 13) in 8 (62 %) patients macro reentry around the mitral valve was found, in 3 (23 %) – reentry around the left pulmonary veins, in another 2 (15 %) of the patients – reentry of the left atrial roof. Conclusions. Non-invasive electrophysiological study with pacemaker can be an effective way to study atrial macro reentry tachyarrhythmias. Electrophysiological PPI-SI criteria less than 20 ms can be used as an additional diagnostic criterion for the selection of patients for surgical treatment. Catheter ablation is recommended for elderly patients when the reentry circle is located in the right atrium.

A machine learning model for non-invasive detection of atherosclerotic coronary artery aneurysm

PurposeAtherosclerosis plays a significant role in the initiation of coronary artery aneurysms (CAA). Although the treatment options for this kind of vascular disease are developing, there are challenges and limitations in both selecting and applying sufficient medical solutions. For surgical interventions, that are novel therapies, non-invasive specific patient-based studies could lead to obtaining more promising results. Despite medical and pathological tests, these pre-surgical investigations require special biomedical and computer-aided engineering techniques. In this study, a machine learning (ML) model is proposed for the non-invasive detection of atherosclerotic CAA for the first time.MethodsThe database for study was collected from hemodynamic analysis and computed tomography angiography (CTA) of 80 CAAs from 61 patients, approved by the Institutional Review Board (IRB). The proposed ML model is formulated for learning by a one-class support vector machine (1SVM) that is a field of ML to provide techniques for outlier and anomaly detection.ResultsThe applied ML algorithms yield reasonable results with high and significant accuracy in designing a procedure for the non-invasive diagnosis of atherosclerotic aneurysms. This proposed method could be employed as a unique artificial intelligence (AI) tool for assurance in clinical decision-making procedures for surgical intervention treatment methods in the future.ConclusionsThe non-invasive diagnosis of the atherosclerotic CAAs, which is one of the vital factors in the accomplishment of endovascular surgeries, is important due to some clinical decisions. Although there is no accurate tool for managing this kind of diagnosis, an ML model that can decrease the probability of endovascular surgical failures, death risk, and post-operational complications is proposed in this study. The model is able to increase the clinical decision accuracy for low-risk selection of treatment options.

A Noninvasive Method for Time-Lapse Imaging of Microbial Interactions and Colony Dynamics.

ABSTRACTComplex interactions between microbial populations can greatly affect the overall properties of a microbial community, sometimes leading to cooperation and mutually beneficial coexistence, or competition and the death or displacement of organisms or subpopulations. Interactions between different biofilm populations are highly relevant in diverse scientific areas, from antimicrobial resistance to microbial ecology. The utilization of modern microscopic techniques has provided a new and interesting insight into how bacteria interact at the cellular level to form and maintain microbial biofilms. However, our ability to follow complex intraspecies and interspecies interactions in vivo at the microscopic level has remained somewhat limited. Here, we detailed BacLive, a novel noninvasive method for tracking bacterial growth and biofilm dynamics using high-resolution fluorescence microscopy and an associated ImageJ processing macro (https://github.com/BacLive) for easier data handling and image analysis. Finally, we provided examples of how BacLive can be used in the analysis of complex bacterial communities.IMPORTANCE Communication and interactions between single cells are continuously defining the structure and composition of microbial communities temporally and spatially. Methods routinely used to study these communities at the cellular level rely on sample manipulation which makes microscopic time-lapse experiments impossible. BacLive was conceived as a method for the noninvasive study of the formation and development of bacterial communities, such as biofilms, and the formation dynamics of specialized subpopulations in time-lapse experiments at a colony level. In addition, we developed a tool to simplify the processing and analysis of the data generated by this method.

Diagnostic utility of MRCP in obstructive jaundice and comparison with CT &amp; ultrasonography

Introduction: With availability of multiple therapeutic options accessible to patients with obstructive jaundice, it is crucial to convey vital information through radiological investigations to decide further management plan. Apart from confirming presence of obstruction in biliary tract and identifying its cause whether benign or malignant, imaging can provide details about anatomical level of obstruction, extent of the pathology as well as its amenability to interventional procedures. Aim and Objective: To evaluate the diagnostic accuracy of Magnetic Resonance Cholangiopancreatography (MRCP) compared with Ultrasound and Computed Tomography (CT) in patients with obstructive jaundice taking findings of ERCP/ PTC and histopathology as gold standard.Materials and Methods: This prospective study included 36 patients who were referred to the department of radio-diagnosis with clinical features of obstructive jaundice.Initial ultrasonography (USG) was followed by Computed tomography (CT) and Magnetic Resonance Cholangiopancreatography (MRCP), however in cases of benign pathologies where USG findings were unequivocal Computed tomography (CT) was not done to avoid unnecessary radiation exposure. The reporting was done by radiologists blinded to other imaging findings. The characteristic Endoscopic Retrograde Cholangiopancreatography (ERCP) features/ histopathological diagnosis (as applicable) were considered as final.Results: For diagnosing the cause of obstructive jaundice, MRI with MRCP has a greater diagnostic accuracy of 94.4% than CT with accuracy is 91.6% and USG with diagnostic accuracy of 30.56%.Conclusion: Ultrasound is a good screening modality to confirm biliary obstruction and to decide whether MRCP is required as next step or not. MRCP is a highly useful non-invasive imaging study in the pre-operative workup of cases with obstructive jaundice.

Evolution of Diagnostic Methods for Infectious and Non-Infectious Uveitis. Review

Uveitis is an inflammation of the uvea (iris, ciliary body, choroid) that can spread to the retina, vitreous and other structures of the eye. Non-infectious uveitis accounts for 31.5 to 82.9 % of cases. The prevalence of infectious uveitis ranges from 13.0 to 54.7 %. Verification of the etiological diagnosis of uveitis requires an individual approach in each clinical case and is based on a thorough analysis of the patient’s medical history, the presence of systemic diseases, and physical examination data, which is supplemented by various laboratory and instrumental examination. However, despite the widespread development of modern diagnostic capabilities, the etiology of uveitis remains unknown in 30–50 % of cases after non-invasive studies, and the treatment is prescribed empirically. At the present stage of studying this issue, the search for a pathological agent, that can play both an etiological role in the development of infectious uveitis and a trigger role in the non-infectious process, is still an urgent task. The article presents a review of the literature on the evolution of methods for the diagnosis of infectious and non-infectious uveitis in accordance with changing ideas about the etiology and pathogenesis of the disease, epidemiological, geographical and socio-economic factors, improving surgical techniques. Pathogenetic aspects and the role of infections in the development of non-infectious uveitis are discussed.

Dynamic behavior of cell-free mitochondrial DNA in human saliva

Mitochondria contain their own genome that can be released in multiple biofluids such as blood and cerebrospinal fluid, as cell-free mitochondrial DNA (cf-mtDNA). In clinical studies, blood cf-mtDNA predicts mortality and higher cf-mtDNA levels are associated with mental and physical stress. However, the dynamics of cf-mtDNA has not been defined, and whether it can be measured non-invasively like other neuroendocrine markers in saliva has not been examined. Here we report cf-mtDNA in human saliva and establish its natural within-person dynamic behavior across multiple weeks. In a small proof-of-principle cohort of healthy adults, we first develop an approach to rapidly quantify salivary cf-mtDNA without DNA isolation, and demonstrate the existence of salivary cf-mtDNA. We then deploy this approach to perform an intensive repeated-measures analysis of two healthy men studied at 4 daily timepoints over 53–60 consecutive days (n = 212–220 observations each) with parallel measures of steroid hormones, self-reported daily mood, and health-related behaviors. Salivary cf-mtDNA exhibited a robust awakening response reaching up to two orders of magnitude 30–45 min after awakening, varied from day-to-day, and moderately correlated with the cortisol awakening response. In exploratory analyses, no consistent association with self-reported daily mood/health-related behaviors were found, although this requires further examination in future studies. Dynamic variation in cf-mtDNA was inversely related with salivary interleukin 6 (IL-6), inconsistent with a pro-inflammatory effect of salivary cf-mtDNA. The highly dynamic behavior of salivary cf-mtDNA opens the door to non-invasive studies examining the relevance of mtDNA signaling in relation to human health.

A novel MMP-responsive nanoplatform with transformable magnetic resonance property for quantitative tumor bioimaging and synergetic chemo-photothermal therapy

Quantifying bio-targeted markers in the tumor microenvironment through non-invasive approaches remains challenging. In this study, a novel matrix metalloproteinase-9 (MMP9) responsive nanoplatform (PMP@USPIO/DOX, PMPSD) with transformable magnetic resonance property is designed for quantitative tumor bioimaging and synergetic chemo-photothermal therapy. The nanoplatform acts as a T2 contrast agent in physiological conditions due to the ultrasmall superparamagnetic iron oxide (USPIO) aggregation state, whereas in the tumor microenvironment, the nanoclusters are dissociated by MMP9, thus transforming the nanoplatform into a T1 contrast agent. T1&T2 weighted image and T1&T2 maps are utilized to quantitatively study the correlation between MRI signal changes and MMP9 concentrations and to evaluate MMP9 activity. In addition, the PMP@USPIO/DOX nanoplatform possesses excellent photothermal properties. PMPSD combined with laser irradiation is more effective than single chemo-/photothermal therapy, and up-regulation of the MMP9 level in the tumor can further improve the therapeutic effect. The nanoplatform is of great significance in evaluating disease prognosis and non-invasive monitoring of drug release. The concept reported here provides a creative idea for the non-invasive quantitative study of the tumor microenvironment.

Non-invasive sleep EEG measurement in hand raised wolves

Sleep research greatly benefits from comparative studies to understand the underlying physiological and environmental factors affecting the different features of sleep, also informing us about the possible evolutionary changes shaping them. Recently, the domestic dog became an exceedingly valuable model species in sleep studies, as the use of non-invasive polysomnography methodologies enables direct comparison with human sleep data. In this study, we applied the same polysomnography protocol to record the sleep of dog’s closest wild relative, the wolf. We measured the sleep of seven captive (six young and one senior), extensively socialized wolves using a fully non-invasive sleep EEG methodology, originally developed for family dogs. We provide the first descriptive analysis of the sleep macrostructure and NREM spectral power density of wolves using a completely non-invasive methodology. For (non-statistical) comparison, we included the same sleep data of similarly aged dogs. Although our sample size was inadequate to perform statistical analyses, we suggest that it may form the basis of an international, multi-site collection of similar samples using our methodology, allowing for generalizable, unbiased conclusions. As we managed to register both macrostructural and spectral sleep data, our procedure appears to be suitable for collecting valid data in other species too, increasing the comparability of non-invasive sleep studies.

OTHR-43. Composition of cell-free miRNA in cerebrospinal fluid and plasma as a monitoring tool for pediatric brain tumors

Current clinical management of pediatric brain tumor patients involves non-invasive imaging studies to monitor therapeutic response and tumor progression. However, results are often inconclusive and unable to capture biological changes that presage progression on imaging. Non-invasive diagnostics, also termed liquid biopsy, have emerged for detection of cell-free cancer material but there are no such standard, clinically defined biomarkers or methods for pediatric brain tumors. Circulating miRNA presents an attractive biomarker platform given its stability in bio-fluids, selective expression in tumors and release from tumor cells into the extracellular environment. Technology development has permitted high throughput analysis of material obtained from biofluids including plasma and cerebrospinal fluid (CSF). We performed miRNA profiling across a cohort of 54 pediatric brain tumors from different histologies (low grade glioma, ependymoma, germinoma, medulloblastoma, atypical teratoid rhabdoid tumor and high-grade glioma) using CSF (33) and plasma (53) with HTG EdgeSeq platform. CSF and plasma specimens clustered independently of each other providing separate biomarker platforms. Consensus clustering performed on CSF specimens revealed clusters correlated with disease severity (tumor grade). We identified miRNA targets closely correlated with tumor grade (p<0.001), tumor dissemination or metastases (p<0.001) and survival (p=0.001). Similarly in plasma, through consensus clustering we identified cohorts with correlation to tumor grade. While distinct from those identified in CSF, specific plasma miRNA also correlated with clinical (tumor grade; p<0.001, dissemination or metastasis; p=0.002) and demographic (gender; p=0.001) features. Independently, histology-specific miRNA signature was also identified for low grade glioma, medulloblastoma and germinoma in plasma and CSF. The results present differential expression of cell-free miRNAs in plasma and CSF as biomarkers associated with diverse clinical diagnostic and prognostic measures. Further utilization of this approach provides unique platforms (plasma and/or CSF) to inform liquid biopsy-based management in the clinical setting.

Role of Doppler Ultrasound in Carotid Kinking and Coiling: A Pictorial Essay and Brief Review

Doppler ultrasound is the initial non-invasive study for the evaluation of the carotid vasculature, it will help us to establish the presence of tortuous paths, the presentation variable, the flow velocities, and if there is a hemodynamic repercussion. In this pictorial review article, the different presentations of carotid tortuosities will be discussed, as well as the correct evaluation of color and spectral Doppler.

P-21 Molecular subtypes (profile) of colorectal cancer and their correlation with clinical and pathological profile in a tertiary care centre in India

Colorectal cancer is a heterogeneous disease with 3 molecular carcinogenesis pathways and 2 morphologic multistep pathways. The varied response rates to the standard therapeutic regimens is due to its heterogeneous tumor biology. A lot of the literature is from the western world on this molecular heterogeneity. We aimed to study the molecular subtypes of colorectal cancer and the correlation with clinical and pathological characteristics in Indian population.Objectives: To evaluate the clinical and pathological profile of colorectal cancers, to determine the frequency of molecular subtypes of colorectal cancers, to correlate between the molecular subtypes and their clinic-pathological features and to determine the association between different molecular subtypes of colorectal cancer. It is a prospective non-invasive interventional study done in 50 patients (both outpatients and inpatients) with newly diagnosed colorectal cancers presenting to Rajiv Gandhi Cancer Institute and Research Centre, Rohini, Delhi from February 2019 to March 2020. Clinical and histopathological data was collected from case sheets as per study proforma- history and physical examination, non-invasive and invasive imaging and histopathological reports. Patients in whom tissue was insufficient or not available for testing for at least 3 molecular markers out of 5 (KRAS, NRAS, BRAF, MSI and MLH1methylation) were excluded. Molecular testing for MMR protein analysis was done using Immunohistochemistry (BenchMark XT, Ventana Medical Systems, Inc., Tucson, AZ, USA). Germline mutation analysis in MSH2, MLH1, PMS2 and MSH6 as dictated by the MMR protein analysis. KRAS, NRAS and BRAF V600E mutation analysis was done by RT-PCR. Methylation of CpG islands of MLH1 is done by pyrosequencing. Results were analyzed with SSPS 23.0 software. For comparison of the frequencies among groups, the Chi-square test and the Fisher exact test were used. P-value <0.05 was considered statistically significant. The median age was 53 years. Majority of males (54%) had CRC. 44% were right sided colon tumors. Of the 50 patients with CRC 40%, 4% and 22% had KRAS mutation, BRAF mutation and deficient MMR respectively. None of the patients was NRAS mutant. KRAS mutation was significantly associated with upfront liver metastases (p=0.02) and well/moderate differentiation (p =0.02). BRAF wild tumors were likely to be well-differentiated (p=0.02) and moreover, half of them (52%) had MLH1 promoter methylation. The proportion of dMMR was higher in male patients (p = 0.04). Deficient mismatch repair was associated with well/moderate differentiation (p = 0.02), early stage (p =0.02) and mild peri-tumoral lymphocytes (p=0.01). None of the MMR deficient patients had Stage IV CRC. 27% patients (3/11) with dMMR tumors had germline mutation of MMR genes. Majority of MMR deficient tumors (43%, 3 out of 7) had MLH1 promoter methylation. Overall, 45% (5/11) dMMR tumors harbored KRAS mutation. In conclusion, this prospective study evaluated the correlations between RAS/BRAF mutation and MMR status with clinico-pathological characteristics in Indian CRC patients, which is mostly similar to worldwide reports with some exceptions. It paves way for future studies to include large populations for validation of the molecular heterogeneity and their prognostic value in Indian population.