REVIEW | doi:10.20944/preprints202105.0083.v1
Subject: Medicine & Pharmacology, Allergology Keywords: COPD; Interstitial lung disease; Combined pulmonary fibrosis and emphysema; interstitial lung abnormalities
Online: 6 May 2021 (12:56:28 CEST)
Although chronic obstructive pulmonary disease (COPD) and interstitial lung disease (ILD) have distinct clinical features, both diseases may coexist in a patient because they share similar risk factors such as smoking, male sex, and old age. Patients with both emphysema in upper lung fields and diffuse ILD are diagnosed with combined pulmonary fibrosis and emphysema (CPFE), which causes substantial clinical deterioration. Patients with CPFE have higher mortality compared with patients who have COPD alone, but results have been inconclusive compared with patients who have idiopathic pulmonary fibrosis (IPF). Poor prognostic factors for CPFE include exacerbation, lung cancer, and pulmonary hypertension. The presence of interstitial lung abnormalities, which may be an early or mild form of ILD, is notable among patients with COPD, and is associated with poor prognosis. Various theories have been proposed regarding the pathophysiology of CPFE. Biomarker analyses have implied that this pathophysiology may be more closely associated with IPF development, rather than COPD or emphysema. Patients with CPFE should be advised to quit smoking and undergo routine lung function tests, and pulmonary rehabilitation may be helpful. Various pharmacologic agents may be beneficial in patients with CPFE, but further studies are needed.
ARTICLE | doi:10.20944/preprints202208.0529.v1
Subject: Medicine & Pharmacology, Cardiology Keywords: Myofibroblast; Atorvastatin; Olmesartan; Resveratrol; Valvular Interstitial Cell
Online: 31 August 2022 (02:55:06 CEST)
Introduction. Recent studies revealed that differentiation of valvular interstitial cell into myoﬁbroblasts played an important role in pathological valve remodeling in rheumatic valvular disease. Objective. To investigate effects of atorvastatin, olmesartan, and resveratrol on Transforming Growth Factor β1-induced fibrosis. Methods. Valvular interstitial cell was isolated from 12-weeks male New Zealand rabbit (Oryctolagus cuniculus). Culture cells was divided into 4 groups, control group, group I (0.5 mg/mL Atorvastatin), group II (100 nmol/L Olmesartan), group III (50 μM/L Resveratrol) and group IV (combinations). All group were exposed to 100 nM Transforming Growth Factor β1 for 24 hours. Results. Immunochemical staining demonstrated that cells were completely differentiated into myofibroblasts with mean expression of α-smooth muscle actin 24522.64±4566.994. Atorvastatin, olmesartan, resveratrol, and its combination significantly reduced α-smooth muscle actin expression (6823±1735.3, 6942.7±2455.9, 14176.2±3343.3, 5051.8±1612.2 respectively (p<0.001). Conclusion. Our data showed atorvastatin, olmesartan, resveratrol, and its combination significantly reduce Transforming Growth Factor β1-induced valvular fibrosis.
ARTICLE | doi:10.20944/preprints202010.0258.v1
Subject: Engineering, Automotive Engineering Keywords: point defect; crystal lattice; interstitial; austenitic; stabilization
Online: 12 October 2020 (16:55:14 CEST)
Bubble (point defect) – a precursor of fuzz or under dense nanostructure formation is crystal lattice defect. Suitable selection of crystal lattice which inhibit Frenkel pair generation and intrinsically promotes selfinterstitial solid solution strengthening contributes effectively towards making plasma facing material. For this, interstitial sites, their size, amount / fraction, positions, tendency of occupation and diffusion parameters (e.g. activation energies (Q), activation volumes) are determined. Fcc iron carbon alloys (austenitic stainless steels AISI / SAE 321, fcc structure, Pearson code cF4, space group Fm3̅m) are proposed as suitable candidates. Along with their room temperature fcc structure having 12 interstitial positions (4 octahedral, 6 coordination sites and 8 tetrahedral, 4 coordination sites / unit cell) to allow insertion of self (iron) atoms, they have excellent corrosion resistance, thermal conductivity, and nonmagnetic properties. After their melting, casting, and machining to required dimensions and geometry, stabilizing heat treatment is applied to precipitate all carbon as TiC and prevent formation of Cr23C6 (sensitization). This resist heat and surface degradation and yield excellent architecture which not only inhibit Frankel pair generation but will also allow bulk assimilation or surface annihilation (loop punching) of this lattice point defect. A superior thermal, fluid, and structural design augment above
ARTICLE | doi:10.20944/preprints202208.0099.v1
Subject: Medicine & Pharmacology, Other Keywords: Interstitial lung disease; Diffuse interstitial lung disease; Idiopathic pulmonary fibrosis; High-resolution computed tomography; Complex Networks; Computer aided diagnosis
Online: 4 August 2022 (04:14:44 CEST)
Diffuse interstitial lung diseases (DILD) are a heterogeneous group of over 200 entities, some with dramatical evolution and poor prognostic. Because of their overlapping clinical, physiopathological and imagistic nature, successful management requires early detection and proper progression evaluation. This paper tests a complex networks (CN) algorithm for imagistic aided diagnosis fitness for the possibility of achieving relevant and novel DILD management data. 65 DILD and 31 normal high resolution computer tomography (HRCT) scans were selected and analyzed with the CN model. The algorithm is showcased in two case reports and then statistical analysis on the entire lot shows that a CN algorithm quantifies progression evaluation with a very fine accuracy, surpassing functional parameters’ variations. The CN algorithm can also be successfully used for early detection, mainly on the ground glass opacity Hounsfield Units band of the scan.
ARTICLE | doi:10.20944/preprints202207.0156.v1
Subject: Engineering, Biomedical & Chemical Engineering Keywords: diffuse interstitial lung disease; complex networks; model; HRCT
Online: 11 July 2022 (09:12:00 CEST)
The High-Resolution Computed Tomography (HRCT) detection and diagnosis of diffuse lung disease is primarily based on the recognition of a limited number of specific abnormal findings, pattern combinations or their distributions, as well as anamnesis and clinical information. Since texture recognition has a very high accuracy percentage if a complex network approach is used, this paper aims to implement such a technique customized for diffuse interstitial lung diseases (DILD). The proposed procedure translates HRCT lung imaging into complex networks by taking samples containing a secondary lobule, converting them into complex networks and analyzing them in 3 dimensions: emphysema, ground glass opacity and consolidation. This method was evaluated on a 60 patient lot and the results show a clear quantifiable difference between healthy and affected lungs. By deconstructing the image on three pathological axes, the method offers an objective way to quantify DILD details which, so far, have only been analyzed subjectively.
ARTICLE | doi:10.20944/preprints202111.0353.v1
Subject: Engineering, Biomedical & Chemical Engineering Keywords: interstitial flow; glioma; chemotaxis; autologous; computational; gradient; CXCL12; migration
Online: 19 November 2021 (13:01:48 CET)
Fluid flow and chemokine gradients play a large part in not only regulating homeostatic processes in the brain, but also in pathologic conditions by directing cell migration. Tumor cells in particular are superior at invading into the brain resulting in tumor recurrence. One mechanism that governs cellular invasion is autologous chemotaxis, whereby pericellular chemokine gradients form due to interstitial fluid flow (IFF) leading cells to migrate up the gradient. Glioma cells have been shown to specifically use CXCL12 to increase their invasion under heightened interstitial flow. Computational modeling of this gradient offers better insight into the extent of its development around single cells, yet very few conditions have been modelled. In this paper, a computational model is developed to investigate how a CXCL12 gradient may form around a tumor cell and what conditions are necessary to affect its formation. Through finite element analysis using COMSOL and coupled convection-diffusion/mass transport equations, we show that velocity (IFF magnitude) has the largest parametric effect on gradient formation, multidirectional fluid flow causes gradient formation in the direction of the resultant which is governed by IFF magnitude, common treatments and flow patterns have a spatiotemporal effect on pericellular gradients, exogenous background concentrations can abrogate the autologous effect depending on how close the cell is to the source, that there is a minimal distance away from the tumor border required for a single cell to establish an autologous gradient, and finally that the development of a gradient formation is highly dependent on specific cell morphology.
ARTICLE | doi:10.20944/preprints201811.0266.v1
Subject: Life Sciences, Molecular Biology Keywords: hypobaric hypoxia; myocardium; interstitial space; fibroblasts; fibrosis; succinic acid; rats
Online: 12 November 2018 (05:16:27 CET)
The myocardial extracellular matrix is not a passive entity, but rather a complex and dynamic microenvironment which represents an important structural and signaling system within the myocardium. Understanding the fundamental role of hypoxia and peroxidation in the genesis of many cardiovascular diseases has stimulated the development of strategies that can enhance the energy-producing functions of cells. Revealing the alterations in cardiac metabolism and function associated with sustained exposure to high altitude advances our understanding of hypoxia-related disease. The study was conducted on 26 adult males of Wistar rats weighing 220–310 g, divided into 3 groups. The first control group consisted of 6 intact animals, the second group included 10 rats which were exposed to hypobaric hypoxia without medication for 30 days. Third group was composed of 10 rats, which were medicated by succinic acid solution which was injected intraperitoneally once a day at the rate of 0.5 mL/100 g of animal body weight 15 minutes before hypoxic exposure for 30 days. Fibrosis in the myocardium inevitably leads to increased myocardial stiffness, resulting in systolic and diastolic dysfunction, neurohormonal activation and, ultimately, heart failure Changes in cardiac highenergy phosphate metabolism may underlie the myocardial dysfunction caused by hypobaric hypoxia. Reduced oxygen delivery by microvascular damage, increased perivascular fibrosis associated with reduced cellular oxygen availability may contribute to contractile failure. Succinic acid combined with inosine acts as a high-energy phosphate reserve, to maintain adenosine triphosphate at levels sufficient to support contractile function.
REVIEW | doi:10.20944/preprints202103.0720.v1
Subject: Engineering, Automotive Engineering Keywords: microneedle; microneedle array, interstitial fluid; bio sensing, wearable system; ISF sampling
Online: 30 March 2021 (09:55:02 CEST)
Dermal interstitial fluid (ISF) is a novel source of biomarkers that can be considered as an alternative to blood sampling for disease diagnosis and treatment. Nevertheless, in vivo extraction and analysis of ISF are challenging. On the other hand, microneedle (MN) technology can address most of the challenges associated with dermal ISF extraction and is well-suited for long-term, continuous ISF monitoring as well as in situ detection. In this review, we first briefly summarise the different dermal ISF collection methods and compare them with MN methods. Next, we elaborate on the design considerations and biocompatibility of MNs. Subsequently, the fabrication technologies of various MNs used for dermal ISF extraction, including solid MNs, hollow MNs, porous MNs and hydrogel MNs, are thoroughly explained. In addition, different sensing mechanisms of ISF detection will be discussed in detail. Subsequently, we identify the challenges and propose the possible solutions associated with ISF extraction. A detailed investigation is provided for the transport and sampling mechanism of ISF in vivo. Also, the current in vitro skin model integrated with the MN arrays will be discussed. Finally, future directions to develop a point-of-care (POC) device to sample ISF are proposed.
ARTICLE | doi:10.20944/preprints202012.0789.v1
Subject: Life Sciences, Biochemistry Keywords: glioblastoma; DCE-MRI; interstitial flow; convection; diffusion; The Cancer Imaging Archive
Online: 31 December 2020 (11:36:28 CET)
Background: Glioblastoma is the deadliest, yet most common, brain tumor in adults, with poor survival and response to aggressive therapy. Therapeutic failure results from a number of causes inherent to these tumors. Imaging, computational, and drug delivery approaches can aid in the quest to access and kill each tumor cell in patients. One factor, interstitial fluid flow, is a driving force therapeutic delivery. However, convective and diffusive transport mechanisms are un-der-studied. In this study, we examine the application of a novel image analysis method to meas-ure fluid flow and diffusion in glioblastoma patients with MRI and compare to patient outcomes. Methods: Building on a prior imaging methodology tested and validated in vitro, in silico and in preclinical models of disease, here we apply our analysis method to archival patient data from the Ivy GAP dataset. Results: We characterize interstitial fluid flow and diffusion patterns in patients. We find strong correlations between flow rates measured within tumors and in the surrounding parenchymal space, where we hypothesized that velocities would be higher. Looking at overall magnitudes, there is significant correlation with both age and survival in this patient cohort. Additionally, we find that tumor size nor resection significantly alter the velocity magnitude. Last, we map the flow pathways in patient tumors and find variability in degree of directionality that we hypothesize in future studies may lead to information concerning treatment, invasive spread, and progression. Conclusions: Analysis of standard DCE-MRI in patients with glioblastoma offers more infor-mation regarding transport within and around tumor, can be measured post-resection and mag-nitudes correlate with patient prognosis.
ARTICLE | doi:10.20944/preprints202006.0049.v1
Subject: Medicine & Pharmacology, Pathology & Pathobiology Keywords: IgAN; miR-148b; let-7b; Tubular atrophy; Interstitial fibrosis; MEST-C
Online: 5 June 2020 (14:06:53 CEST)
IgA nephropathy (IgAN) is one of the most common forms of glomerular disease. It is diagnosed by the dominant or co-dominant IgA deposition in the mesangial region by histopathological examination of kidney biopsy. Kidney biopsy has its own complication and not performed frequently. microRNA (miRNA) is a small RNA, which plays an important role at the post transcriptional level by downregulating mRNAs. We have tried to establish a miRNA based biomarker for IgAN. We quantified miR-148b and let-7b from plasma in IgAN patients and healthy controls. Logistic regression models and receiver operating curve analysis used to analyze the miRNAs quantity and Oxford MEST-C scoring parameters (M- Mesangial hypercellularity, E- Endocapillary hypercellularity, S- Segmental glomerulosclerosis, T- Tubular atrophy/Interstitial fibrosis, C- Crescents). miR-148b and let-7b levels in IgAN were found to be higher by 2.9 and 5.48 times than the healthy controls, respectively. let-7b was positively correlated with complement C3 levels. Similarly, miR-148b was positively correlated with estimated glomerular filtration rate (eGFR) and negatively correlated with S, T, and blood pressure (BP). The sensitivity, specificity, and area under the curve (AUC) of receiver operating characteristic (ROC) for miR-148b against T were 0.87, 0.77, and 0.85, respectively. The threshold value of miR-148b concentration was found to be 8479 to differentiate the severe condition of IgAN. Furthermore, the decrease in miR-148b concentration at a threshold point indicated the progression of the severity of the IgAN. It can also be used to predict the IgAN at an earlier stage.
ARTICLE | doi:10.20944/preprints201801.0033.v1
Subject: Materials Science, Biomaterials Keywords: tissue engineering; lumen; stem cells, interstitial cells of Cajal; hydrogel scaffolds
Online: 5 January 2018 (09:36:18 CET)
Gastroparesis (GP) is associated with depletion of interstitial cells of Cajal (ICC) and enteric neurons, which leads to pyloric dysfunction followed by severe nausea, vomiting and delayed gastric-emptying. Regenerating these fundamental structures with stem cell therapy, would be helpful to restore gastric function in GP. Mesenchymal stem cells (MSC) have been successfully used in animal models of other gastrointestinal (GI) diseases including colitis. However, no study has been performed with these cells on GP animals. In this study, we explored if mouse MSC can be delivered from a hydrogel-scaffold to the luminal surfaces of GP mice stomach. Mouse MSC was seeded atop alginate-gelatin, coated with poly-L-lysine. These cell-gel constructs were placed atop stomach explants facing the luminal side. MSC grew uniformly all across the gel surface within 48 hr. When placed atop the lumen of the stomach, MSC migrated from the gels to the tissues as confirmed by positive staining with Vimentin and N-cadherin. The feasibility of transplanting a cell-gel construct to deliver stem cells in the stomach wall was successfully shown in a mice GP model, thereby making a significant advance towards envisioning the transplantation of an entire tissue-engineered ‘gastric patch’ or ‘microgels’ with stem cells, and growth factors.
ARTICLE | doi:10.20944/preprints201901.0033.v1
Subject: Materials Science, Metallurgy Keywords: W-O alloy, interstitial solid solution, screw dislocations, solute diffusion, stress coupling
Online: 4 January 2019 (08:42:36 CET)
Plastic flow in body-centered cubic (bcc) alloys is governed by the thermally-activated screw dislocation motion. In bcc interstitial solid solutions, solute diffusion can occur at very fast rates owing to low migration energies and solute concentrations. Under mechanical loading, solutes may move on the same or similar time scale as dislocations glide, even at low temperatures, potentially resulting in very rich co-evolution processes that may have important effects in the overall material response. It is therefore important to accurately quantify the coupling between interstitial impurities and dislocations, so that larger-scale models can correctly account for their (co)evolution. In this paper, we use electronic structure calculations to obtain the energetics of oxygen diffusion under stress and its interaction energy with screw dislocation cores in bcc tungsten. We find that oxygen atoms preferentially migrate from tetrahedral to tetrahedral sites with an energy of 0.2 eV. This energy couples only weakly to hydrostatic and deviatoric deformations, with activation volumes of less than $0.02$ and $0.2b^3$, respectively. The strongest effect is found for the inelastic interaction between O atoms and screw dislocation cores, which leads to attractive energies on the order of 1.5 eV and a structural transformation of the screw dislocation core from an `easy' to a `hard' core configuration
REVIEW | doi:10.20944/preprints202105.0164.v1
Subject: Medicine & Pharmacology, Allergology Keywords: kidney health; population health; social determinants; sociopolitical context; environment; advocacy; interstitial nephritis; conservative care; dialysis; funding; kidney failure
Online: 10 May 2021 (10:41:49 CEST)
Statistical data extracted from national databases demonstrate a continuous growth in the incidence and prevalence of chronic kidney disease (CKD) and the ineffectiveness of current policies and strategies based on individual risk factors to reduce them, as well as their mortality and costs. Some innovative programs, telemedicine and government interest in the prevention of CKD, did not facilitate timely access to care, continuing the increased demand for dialysis and transplants, high morbidity and long-term disability. In contrast, new forms of kidney disease of unknown etiology affected populations in developing countries and underrepresented minorities, who face socioeconomic and cultural disadvantages. With this background, we analyze in the existing literature the effects of social determinants in CKD, concluding that it is necessary to strengthen current kidney health strategies, designing in a transdisciplinary way, a model that considers demographic characteristics integrated into individual risk factors and risk factors population, incorporating the population health perspective in public health policies to improve results in kidney health care, since CKD continues to be an important and growing contributor to chronic diseases.
Subject: Medicine & Pharmacology, General Medical Research Keywords: SARS-CoV-2 COVID-19; lung damage mechanisms; leukecyte recruitment; viral infection; immune response; temperature and humidity; interstitial pressure change
Online: 9 September 2020 (11:32:55 CEST)
To understand lung damage caused by COVID-19, we deduced two-phase lung damage mechanisms. After the lungs are infected with SARS-CoV-2 virus, the affected lung tissue swells and surface properties of pulmonary capillaries change, resulting in an increased flow resistance of affected capillaries. If a sufficient number of capillaries are affected by the infection, the swelling and increased cell wall adhesion collectively raise pulmonary vascular resistance. The increased vascular resistance further increases the dwell times of WBCs in affected capillaries and nearly capillaries. When pulmonary pressure is sufficiently higher, WBCs are forced to squeeze into interstitial spaces or alveolar spaces when local pressures are higher than what the capillaries can withstand. When more and more WBCs are dynamically retained, the flow resistance of more capillaries rises, pulmonary vascular resistance rises, and pulmonary pressure rises. The rise in the pulmonary pressure in turn results in elevated capillary pressures. When capillary pressures around the alveoli are sufficiently high, they cause interstitial pressures to change from normally negative values to positive values. The positive pressures cause fluid leakage to the alveolar space and thus degrade lung function. Tissue swelling, and occupation of WBCs in interstitial spaces and alveolar spaces further reduce compressible volume, and thus cause further rise in the pulmonary vascular resistance and pulmonary pressure. When the pulmonary pressure has reached a critical point as in the second phase, the blood breaks capillary walls and squeezes through interstitial spaces to reach alveolar spaces, resulting in irreversible lung damages. The available free volume in the thorax cage, organ usable capacities, temperature and humid are expected to have great impacts on degree of lung damages. The free volume in the thorax cage, lung usable surplus capacity, and other organ usable capacities determine the arrival time of last-phase irreversible damage. The mechanisms imply that the top priority for protecting lungs is maintaining pulmonary micro-circulation and preserving organ functions in the entire disease course while controlling viral reproduction should be stressed in the earliest time possible. The mechanisms also explain leukecytes are recruited and migrated into inflamed tissues by increasing their dwell times caused by increased local flow resistance.
ARTICLE | doi:10.20944/preprints202012.0697.v1
Subject: Life Sciences, Biochemistry Keywords: Repeat-Induced Point Mutations; RIP; Accessory Chromosome; Genome Compartmentalization; GC Content; Genetic Variation; Fusarium circinatum; Transposable Elements; Interstitial Telomeric Repeats; Effector Genes.
Online: 28 December 2020 (12:18:11 CET)
Repeat-Induced Point mutations (RIP) serves as a genome defence mechanism that impedes the deleterious consequences of repeated motifs such as transposable elements in fungi. Genomic regions with RIP are biased for adenosine and thymine transitions and the cumulative influence of RIP is thought to have a considerable impact on genome composition. We investigated the impact of RIP on localized genomic regions and whole-genome sequences for representatives of the pine pathogen, Fusarium circinatum. We set out to determine the intraspecific variation in acquired RIP and the role of RIP in the development of diverse F. circinatum sub-genomic compartments. The results of the study show that the AT-enriched sub-genomic compartment accounts for ca. 97% of the calculated RIP and was further prominent in both core and accessory genomic regions. However, more extensive RIP was observed in the accessory sub-compartment and more variable regions of the genome. Regions with RIP indicated increased intrinsic curvature of the DNA which may influence DNA-protein interactions and may promote constitutive heterochromatin formation. The results show that RIP is an important source of functional novelty and genome variation. RIP contributes to the evolution of the genetic landscape and differentiation of diverse sub-genomic compartments of this important fungal pathogen.
REVIEW | doi:10.20944/preprints202209.0125.v1
Subject: Medicine & Pharmacology, Other Keywords: Human serum albumin; COVID-19 vulnerabilities; fluid therapy; albumin binding deficiency; lymphatic nutrient pump; colloid pressure; interstitial spaces; albumin infusion; hepatic portal vein
Online: 8 September 2022 (13:40:16 CEST)
COVID-19 and long COVID-19 vulnerabilities may be caused indirectly by albumin binding deficiency (ABD) which can be corrected by the correct administration of human serum albumin (HSA). The liver is the primary site of nutrient regulation and fluid volume maintenance, control of both is by changes to albumin concentration. In healthy subjects the HSA lymphatic nutrient pump (HSALNP) ensures continual pumping of nutrients from the liver are appropriately distributed to organs. Nutrients are delivered to cells according to the availability of binding to HSA. The HSALNP therefore maintains the correct nutrients and colloidal pressure balance in all tissues independently. In unhealthy tissues, following COVID-19 infection, the passage of HSA/nutrients through the interstitial spaces and lymph will be impeded. Fluid therapy into the periphery leads to dilution of essential nutrients attached to the protein-carriers such as albumin. The levels of albumin being charged by the liver with nutrients is critical in maintaining immune stability by maintaining nutrient support and colloidal pressure of cellular structures. The site of HSA binding by the liver is of great importance and direct infusion of albumin into the Hepatic Portal Vein is the most appropriate method of maintaining colloid pressure and cellular nutrient levels.
ARTICLE | doi:10.20944/preprints202105.0522.v1
Subject: Life Sciences, Biochemistry Keywords: Cerium oxide NPs; acute and subchronic toxicity; in vitro; pulmonary and interstitial cell lines; human airway epithelial model; air-liquid interface; aerosolized NPs.
Online: 21 May 2021 (13:17:36 CEST)
Engineered nanomaterials (ENMs) are of significant relevance due to their unique properties, which have been exploited for widespread applications. Cerium oxide nanoparticles (CeO2-NPs) are one of most exploited ENM in the industry due to their excellent catalytic and multi-enzyme mimetic properties. Thus, toxicological effects of these ENMs should be further studied. Acute and subchronic toxicity of CeO2-NPs were assessed. First an in vitro multi-dose short-term (24h) toxicological assessment was performed in three different cell lines: A549 and Calu3, representing the lung tissue, and 3T3 as an interstitial tissue model. After that, a sub-chronic toxicity assessment (90 days) of these NPs was carried out on a realistic and well stablished reconstituted primary human airway epithelial model (MucilAir™), cultured at the Air-Liquid Interface (ALI), to study long-term effects of these particles. Results showed minor toxicity of CeO2-NPs in acute exposures. However, in subchronic exposures, cytotoxic and inflammatory responses were observed in the human airway epithelial model after 60 days of exposure to CeO2-NPs. These results suggest that acute toxicity approaches may underestimate the toxicological effect of some ENM, highlighting the need of subchronic toxicological studies in order to accurately assess the toxicity of ENM and their cumulative effects in the organism.
ARTICLE | doi:10.20944/preprints202201.0401.v1
Subject: Engineering, Biomedical & Chemical Engineering Keywords: Interstitial Hyperthermia; Automated treatment planning; Electromagnetic simulations; ThermoBrachytherapy; High dose rate brachytherapy; Quasistatic simulations; Capacitive heating; Treatment plan optimization; Finite-Difference Time-Domain; Gamma index analysis.
Online: 26 January 2022 (13:14:59 CET)
The combination of interstitial hyperthermia treatment (IHT) with high dose rate brachytherapy (HDR-BT) for prostate cancer treatment and has the potential to improve clinical outcome, since it highly enhances the efficiency of cell kill, especially when applied simultaneously. Therefore, we have developed the ThermoBrachy applicators. To effectively apply optimal targeted IHT, treatment planning is considered essential. However, treatment planning in IHT is rarely applied since it is regarded difficult to accurately calculate the deposited energy in the tissue in a short enough time for clinical practice. In this study, we investigated various time-efficient methods for fast computation of the electromagnetic (EM) energy deposition resulting from the ThermoBrachy applicators. Initially, we investigated the use of an electro-quasistatic solver. Next, we extended our investigation to the application of geometric simplifications. Furthermore, we investigated the validity of the superpositioning principle, which can enable adaptive treatment plan optimization without the need for continuous recomputation of the EM field. Finally, we evaluated the accuracy of the methods by comparing them to the golden standard Finite-Difference Time-Domain calculation method using gamma-index analysis. The simplifications considerably reduced the computation time needed, improving from >12 h to a few seconds. All investigated methods showed excellent agreement with the golden standard by showing a >99% passing rate with 1%/0.5 mm Dose Difference and Distance-to-Agreement criteria. These results allow the proposed electromagnetic simulation method to be used for fast and accurate adaptive treatment planning.
ARTICLE | doi:10.20944/preprints202108.0210.v1
Subject: Medicine & Pharmacology, Other Keywords: microscopic polyangiitis; granulomatosis with poliangiitis; eosinophilic granulomatosis with poliangiitis; kidney biopsy; pauci-immune focal and segmental necrotizing and crescentic glomerulonephritis; tubular atrophy and interstitial fibrosis; kidney survival
Online: 10 August 2021 (07:59:00 CEST)
ANCA-associated vasculitis (AAV) pose a significant risk of kidney failure, kidney biopsy remains a key prognostic tool. Pathology classification of the AAV glomerulonephritis (GN) developed by Berden et al showed correlation between GN classes and kidney outcomes; ANCA Renal Risk Score (ARRS) included tubular atrophy and interstitial fibrosis (TA/IF) as an additional parameter for risk assessment. We aimed to evaluate kidney survival across AAV GN classes and ARRS groups. A single-center retrospective study included 85 adult patients with biopsy-proven AAV kidney disease followed in 2000-2020. Primary outcome was kidney survival at the end of 18 [5; 66] months follow-up, kidney death considered as CKD stage 5. We found significant difference in the kidney survival for sclerotic, mixed, crescentic and focal AAV GN classes: 19%, 76.2%, 91.7% and 100% respectively (p=0.009). Kidney survival was 0%, 75.6% and 100% for the high, median and low risk ARRS groups respectively (p<0.001); TA/IF analysis showed kidney survival 49.6% vs 87.7% for widespread and mild TA/IF respectively (р=0.003). Kidney survival was significantly lower in anti-MPO-ANCA versus anti-PR3-ANCA carriers (50.3% and 78.1% respectively, р=0.045). We conclude that unfavorable AAV kidney outcomes associated with sclerotic GN class by Berden’s classification, ARRS high risk group, and anti-MPO-ANCA subtype.