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Biotechnological production of the European corn borer sex pheromone in the yeast Yar...
Karolis Petkevicius
Eleni Koutsoumpeli

Karolis Petkevicius

and 15 more

January 14, 2021
The European corn borer (ECB) Ostrinia nubilalis is a widespread pest of cereals. Mating disruption with the sex pheromone is a potentially attractive method for managing this pest. The goal of this study was to develop a biotechnological method for the production of ECB sex pheromone. Our approach was to engineer the oleaginous yeast Yarrowia lipolytica to produce (Z)-11-tetradecenol (Z11-14:OH), which can be chemically acetylated to (Z)-11-tetradecenyl acetate (Z11-14:OAc), the main pheromone component of the Z-race of O. nubilalis. Fatty acyl-CoA desaturases (FAD) and fatty acyl-CoA reductases (FAR) from nine different species of Lepidoptera were screened individually and in combinations. A titer of 29.2±1.6 mg/L Z11-14:OH was reached in small-scale cultivation with an optimal combination of a FAD (Lbo_PPTQ) from Lobesia botrana and FAR (HarFAR) from Helicoverpa armigera. When the second copies of FAD and FAR genes were introduced, the titer improved 2.1-fold. The native FAS1 gene’s overexpression led to a further 1.5-fold titer increase. When the same engineered strain was cultivated in controlled 1 L bioreactors in fed-batch mode, 188.1±13.4 mg/L of Z11-14:OH was obtained. Fatty alcohols were chemically acetylated to obtain Z11-14:OAc. Electroantennogram experiments showed that males of the Z-race of O. nubilalis were responsive to biologically-derived pheromone blend. Behavioral bioassays in a wind tunnel revealed attraction of male O. nubilalis at a level similar to that of the chemically synthesized pheromone used as a control, although full precopulatory behavior was observed less often. The study paves the way for the production of ECB pheromone by fermentation.
Prediction of Cardiovascular Adverse Events in Patients Treated with R-CHOP Regimens...
Yi-Hui Shen
Hui Zhang

Yi-Hui Shen

and 7 more

January 14, 2021
Background: Patients treated for lymphoma are at risk of cardiovascular adverse events. Global longitudinal strain (GLS) and global circumferential strain (GCS) were reported for predicting cardiovascular adverse events in patients treated with doxorubicin. However, the prognostic value of RV ejection fraction by 3D transthoracic echocardiography (3D TTE) have not been elucidated yet. We hypothesized that RV echocardiography parameters increases the sensitivity for predicting the later CAE. Methods: In this retrospective study, ninety-six patients with diffuse large B-cell lymphoma with normal cardiac function treated with R-CHOP regimen were studied between January 2013 and January 2015 by 3D TTE. Basic demographic data, oncology and echocardiography parameters were measured. The main outcomes were the proportion of patients with grade 3–4 cardiovascular adverse events (CAE). The association of pre-chemotherapy and post-chemotherapy echocardiography parameters with CAEs was analyzed using proportional hazard analysis. Results: Over a median follow-up period of 6.1 years (range, 4.9-7.6 years) after the completion of chemotherapy, 18 of 96 patients (19%) experienced CAEs. Univariate predictors of CAE (P < .05) were LVGLS, LVGCS, RVEF, and RVESV. Multivariate analysis of all significant univariate variables showed that RVEF (hazard ratio, 0.848; 95% confidence interval,0.785–0.916; P < .001) were significantly and independently associated with CAE. Stepwise analysis of the multivariate associations showed an increase in the global x2 value after adding LVEF (P < .001) to significant clinical variables. Conclusion: LVGLS and RVEF were significantly and independently associated with CAE in patients. Adding RVEF to other clinical variables provided incremental prognostic information.
Expanding forests in alpine regions: space-for-time indicates a corresponding shift i...
Lea-Rebekka Tonjer
Ella Thoen

Lea-Rebekka Tonjer

and 7 more

January 14, 2021
Climate change causes upward shift of forest lines worldwide, with consequences on soil biota and carbon (C). Using a space-for-time approach, we analyse compositional changes in the soil biota across the forest line ecotone, an important transition zone between different ecosystems. We collected soil samples along transects stretching from subalpine mountain birch forests to low-alpine vegetation. Soil fungi and micro-eukaryotes were surveyed using DNA metabarcoding of the 18S and ITS2 markers, while ergosterol was used to quantify fungal biomass. We observed a strong shift in the soil biota across the forest line ecotone: Below the forest line, there were higher proportions of basidiomycetes and mucoromycetes, including ectomycorrhizal and saprotrophic fungi. Above, we observed relatively more root-associated ascomycetes, including Archaeorhizomycetes, ericoid mycorrhizal fungi and dark septate endophytes. Ergosterol and percentage C content in soil strongly and positively correlated with the abundance of root-associated ascomycetes. The predominance of ectomycorrhizal and saprotrophic fungi below the forest line likely promote high C turnover, while root-associated ascomycetes above the forest line may enhance C sequestration. With further rise in forest lines, there will be a corresponding shift in the belowground biota linked to C sequestration processes.
Treatment of fracture dislocation of the femoral head using safe surgical hip disloca...
Paa BAIDOO
Kwasi Twumasi-Baah Jnr

Paa BAIDOO

and 5 more

January 14, 2021
We report the clinical and radiological outcomes of a 30-year-old female with femoral head fracture following a posterior hip dislocation. The patient was managed using safe surgical hip dislocation and reviewed the literature on Pipkin type I fractures.
Negative Theology; A Comparative Study on Ibn Arabi and Eckhart
Hossein  Shaqaqi

Hossein Shaqaqi

January 14, 2021
A document by Hossein Shaqaqi, written on Authorea.
Tension Orbit secondary to a carious primary molar- A case report.
Mehul Jaisani
Ashok Dongol

Mehul Jaisani

and 10 more

January 14, 2021
In this case report we present a case of a eight years old boy who presented with progressive orbital cellulitis causing endangered vision secondary to carious primary maxillary molar. The patient was appropriately managed with intravenous antibiotics, steroids and surgical decompression. Significant morbidity was overcome by multi-specialty team approach.
Evaluation Of Laryngeal Vascular Changes With Image1 S Enhancement System In Referenc...
Sibel Yıldırım
Tarık Küçük

Sibel Yıldırım

and 5 more

January 14, 2021
Objectives: To assess the feasibility of using Image1 S™ endoscopic enhancement system for discrimination of the vascular patterns in laryngeal lesions. Design: Forty patients presenting with benign, dysplastic and malign laryngeal lesions were examined with Image1 S system. The vascular patterns were classified by a group of the authors/ according to the ELS guideline, as perpendicular or longitudinal, in all lesions. Endoscopic images of the vascular patterns are evaluated through an online survey by a group of otolaryngologists with different levels of clinical expertise. The qualitative evaluation of the vascular patterns in two groups were compared to investigate the consistency. The relationship between the vascular patterns and the pathological results was statistically analyzed. Results: Eleven patient presented with benign, 13 patients with dysplastic and 16 patients with malignant pathology. The vascular patterns were longitudinal in 9 lesions, perpendicular in 28 lesions and undetectable in 3 lesions. The relevance between the vascularization pattern and the pathological diagnosis was found to be significant (χ2= 20.30, p < 0,001). The qualitative evaluation of the vascular patterns by the two groups of observers was significantly close to each other (=0.63). The survey also showed that spectral modes producing high contrast images were preferred by 81,9% of the participants over white light images. Conclusion: This study demonstrated the usefulness and feasibility of Image1 S endoscopic enhancement system to predict the diagnosis from vascular changes in laryngeal lesions.
Indoor exposure to airborne PAHs: A comparison of stir bar sorptive extraction and pu...
Roland Becker
Lisa Heyn

Roland Becker

and 2 more

January 14, 2021
Stir bar sorptive extraction (SBSE) was compared with standardized pump sampling regarding the prospects to assess airborne levels of polycyclic aromatic hydrocarbons (PAHs) in indoor environments. A historic railway water tower, which will be preserved aa technical monument for museum purposes, was sampled with both approaches because built-in insulation material was suspected to release PAHs to the indoor air. The 16 PAH on the US EPA list were quantified using gas chromatography with mass selection detection in filters from pump sampling after solvent extraction and on SBSE devices after thermal desorption. SBSE was seen to sample detectable PAH masses with excellent repeatability and a congener pattern largely similar to that observed with pump sampling. Congener patterns were however significantly different from that in the PAH source because release from the insulation material is largely triggered by the respective congener vapor pressures. Absolute masses in the ng range sampled by SBSE corresponded to airborne concentrations in the ng L -1 range determined by pump sampling. Principle differences between SBSE and pump sampling as well as prospects of SBSE as cost-effective and versatile complement of pump sampling are discussed.
Reprogram Frozen Embryo Transfers to Allow For a More “Natural” Approach
Bruce Pier
Logan Havemann

Bruce Pier

and 2 more

January 14, 2021
Reprogram Frozen Embryo Transfers to Allow For a More “Natural” Approach
Evaluation of the PRE-DELIRIC (PREdiction of DELIRium in ICu patients) delirium predi...
Samet Sayılan
Volkan Ozen

Samet Sayılan

and 4 more

January 14, 2021
Purpose: This methodological study was aimed to the Turkish adaptation and validation of the “PRE-DELIRIC Score” delirium prediction model in patients hospitalized in the ICU. Method: The study was conducted with patients who were treated in the ICUs of a training and research hospital between October 2019 and April 2020. The data were collected with (1) the Data Collection Form for the Descriptive Characteristics of the Subjects, (2) the PRE-DELIRIC Score, and (3) the Confusion Assessment Method for the ICU (CAM-ICU). The ROC analysis and diagnosis screening tests were used to determine the cut-off point according to the groups. The sensitivity and specificity characteristic of the score were calculated. Significance was evaluated at the p<0.05 level. Results: The study was completed with 172 patients. A statistically significant relationship was found between the cut-off point obtained for the PRE-DELIRIC Score (≥7.58%) and the groups (p= 0.003). The risk of being CAM-ICU positive was 7.404 times higher in patients with a PRE-DELIRIC Score of 7.58 or more (OR:7.404; 95% CI:1.638-33.469). Conclusion: The PRE-DELIRIC Score was evaluated in this study and the PRE-DELIRIC Score was found to be easy to administer with reliable results.
EVALUATION OF THE INFECTION AWARENESS OF DENTISTS DURING COVID-19 PANDEMIC
SANAZ SADRY
Zeynep Sapan

SANAZ SADRY

and 1 more

January 14, 2021
Background: The present study aims to investigate the state of sterilization, disinfection and infection control of dentists during the COVID-19 pandemic. Methods: The study involved 310 dentists, who were asked to fill in a 19-question, multiple-choice survey on sterilization, disinfection and infection control. The survey results were evaluated statistically using chi-square test. Results: An investigation of the changes in working conditions and occupational experience during the pandemic period showed that 86.7% of the physicians who quit are the ones with occupational experience of 0 to 6 years. 89.3% of the physicians who answered “No idea” to the question about sterilization methods consist of physicians with over 20 years of experience, while 7.1% of them are physicians with 6-10 years of experience. Conclusion: Dentistry is the highest risk profession in the COVID-19 pandemic. And dentists need to reduce this risk by utilizing personal protective equipment and adopting the most appropriate disinfection and sterilization measures. Key Words: Disinfection, dentistry, sterilization.
Numerical Solution of Schrodinger Equation for Rotating Morse Potential using Matrix...
Aditi Sharma
O S K Sastri

Aditi sharma

and 1 more

January 14, 2021
In this paper, an elegant and easy to implement numerical method using matrix mechanics approach is proposed, to solve the time independent Schrodinger equation (TISE) for Morse potential. It is specifically applied to non-homogeneous diatomic molecule HCl to obtain its rotating-vibrator spectrum. While matrix diagonalization technique is utilised for solving TISE, model parameters for Morse potential are optimized using variational Monte-Carlo (VMC) approach by minimizing χ 2 − value. Thus, validation with experimental vibrational frequencies is completely numerical based with no recourse to analytical solutions. The ro-vibrational spectra of HCl molecule obtained using the optimized parameters through VMC have resulted in least χ 2 − value as compared to those determined using best parameters from multiple regression analysis of analytical expressions. Numerical algorithm for solving the Hamiltonian matrix has been implemented utilizing Free Open Source Software (FOSS) Scilab and simulation results are matching well with those obtained using analytical solutions from Nikiforov-Uvarov (NU) method and asymptotic iteration method (AIM).
Ethanol resistance in Drosophila melanogaster has increased in parallel cold-adapted...
Quentin Sprengelmeyer
John E Pool

Quentin Sprengelmeyer

and 1 more

January 14, 2021
Understanding the genetic properties of adaptive trait evolution is a fundamental crux of biological inquiry that links molecular processes to biological diversity. Important uncertainties persist regarding the genetic predictability of adaptive trait change, the role of standing variation, and whether adaptation tends to result in the fixation of favored variants. Here, we use the recurrent evolution of enhanced ethanol resistance in Drosophila melanogaster during this species' worldwide expansion as a promising system to add to our understanding of the genetics of adaptation. We find that elevated ethanol resistance has evolved at least three times in different cooler regions of the species' modern range - not only at high latitude but also in two African high altitude regions - and that ethanol and cold resistance may have a partially shared genetic basis. Applying a bulk segregant mapping framework, we find that the genetic architecture of ethanol resistance evolution differs substantially not only between our three resistant populations, but also between two crosses involving the same European population. We then apply population genetic scans for local adaptation within our quantitative trait locus regions, and we find potential contributions of genes with annotated roles in spindle localization, membrane composition, sterol and alcohol metabolism, and other processes. We also apply simulation-based analyses that confirm the variable genetic basis of ethanol resistance and hint at a moderately polygenic architecture. However, these simulations indicate that larger-scale studies will be needed to more clearly quantify the genetic architecture of adaptive evolution, and to firmly connect trait evolution to specific causative loci.
Functional relationship between woody plants and insect communities in response to Bu...
Zhuang Wang
Lijuan Zhao

Zhuang Wang

and 6 more

January 14, 2021
To study the effect of the invasion of Bursaphelenchus xylophilus on the functional relationship between woody plants and insect communities, the populations of tree species and insect communities were investigative in the Masson pine forests with different infestation durations of B. xylophilus. In this study, the number of Pinus massoniana began to decrease sharply, whereas the total number of other tree species in the arboreal layer increased gradually with the infestation duration of B. xylophilus. The principal component analysis ordination biplot shows that there was a significant change in the spatial distribution of woody plant species in different Masson pine forest stands. Additionally, a total of 7,188 insect specimens was obtained. The insect population showed an upward trend in stand types with the increase of pine wilt disease infection periods, which demonstrated that the insect community had been significantly affected by the invasion of B. xylophilus. The structure of insect functional groups changed from herbivorous (He) > omnivorous (Om) > predatory (Pr) > parasitic (Pa) > detritivorous (De) in the control stand to He > Pa > Om, De > Pr after B. xylophilus infestation in the forests. The results showed that the populations of He, Pa, and De increased after the invasion of B. xylophilus, but the populations of Pr decreased. Moreover, the redundancy analysis ordination bi-plots reflected the complicated functional relationship between woody plant communities and insects after the invasion of B. xylophilus. The present study provides insights into the changes in the community structure of woody plants and insects, as well as the functional relationship between woody plant communities and insect communities after invasion of B. xylophilus.
Den characteristics and ecological significance of Marmota himalayana on the Qinghai-...
Shulin Wang
Fujiang Hou

Shulin Wang

and 1 more

January 14, 2021
Dens are places for cavernicolous animals to hibernate, reproduce, and avoid predators and harsh weather conditions, and thus they have a vital impact on their survival. M. himalayana is the main large cavernicolous rodent on the Qinghai-Tibet Plateau. The analysis of den traits and their ecological functions can reveal mechanisms by which marmots have adapted to their environment, which is important for further understanding the ecological significance of this species. From July to August 2019 (warm season), we used unmanned aerial vehicles to fly at low altitudes and slow speeds to locate 131 marmot burrows (45 on shaded slopes, 51 on sunny slopes, and 35 on flat areas) in the northeastern Qinghai-Tibet Plateau. We then measured the physical characteristics (den density, entrance size, first tunnel length, volume, orientation and plant characteristics near the den entrance) of these dens on site. The physical parameters of the M. himalayana dens showed that they function to protect the marmots from natural enemies and bad weather, provide good drainage, and maintain a stable microclimate around the entrance. This is a result of the marmot’s adaptation to the harsh environment (cold and humidity) of the Qinghai-Tibet Plateau.
A Paramount Problem Solved at Last: Paramagnetic Catalysis of Ortho-Para Hydrogen Con...
Bretislav Friedrich

Bretislav Friedrich

January 14, 2021
A document by Bretislav Friedrich, written on Authorea.
Quantum Phases and Chern-Simons Geometrics for the generation of a ligand targeting C...
Ioannis Grigoriadis

Ioannis Grigoriadis

January 14, 2021
SARS coronavirus 2 (SARS-CoV-2) in the viral spike (S) encoding a SARS-COV-2 SPIKE D614G mutation protein predominate over time in locales revealing the dynamic aspects of its key viral processes where it is found, implying that this change enhances viral transmission. It has also been observed that retroviruses infected ACE2-expressing cells pseudotyped with SG614 that is presently affecting a growing number of countries markedly more efficiently than those with SD614. The availability of newer powerful computational resources, molecular modeling techniques, and cheminformatics quality data have made it feasible to generate reliable algebraic calculations to design new chemical entities, merging chemicals, recoring natural products, and a lot of other substances fuelling further development and growth of this AI-quantum based drug design field to balance the trade-off between the structural complexity and the quality of such biophysics predictions that cannot be obtained by any other method. In this paper, we strongly combine topology geometric methods targeting at the atomistic level the protein apparatus of the SARS-COV-2 virus that are simple in machine learning anti-viral characteristics, to propose computer-aided rational drug design strategies efficient in computing docking usage, and powerful enough to achieve very high accuracy levels for this in-silico effort for the generation of the AI-Quantum designed molecule the RoccustyrnaTM small molecule, a multi-targeting druggable scaffold (1S,2R,3S)‐2‐({[(1S,2S,4S,5R)‐4‐ethenyl‐4‐sulfonylbicyclo[3.2.0]heptan‐2‐yl]oxy}amino)‐3‐[(2R,5R)‐5‐(2‐methyl‐6‐methylidene‐6,9‐dihydro‐3H‐purin‐9‐yl)‐3‐methylideneoxolan‐2‐yl]phosphirane‐1‐carbonitrile targeting the COVID-19-SARS-COV-2 SPIKE D614G mutation using Chern-Simons Topology Euclidean Geometric in a Lindenbaum-Tarski generated QSAR automating modeling and Artificial Intelligence-Driven Predictive Neural Networks.
Geometric Hashing and ΑΙ-Quantum Deep Learning functional similarities on Remdesivir,...
Ioannis Grigoriadis

Ioannis Grigoriadis

January 14, 2021
Νovel SARS coronavirus 2 (SARS-CoV-2) of the family Coronaviridae starting in China and spreading around the world is an enveloped, positive-sense, single-stranded RNA of the genus betacoronavirus encoding the SARS-COV-2 (2019-NCOV, Coronavirus Disease 2019. Remdesivir drug, or GS-5734 lead compound, first described in 2016 as a potential anti-viral agent for Ebola diseade and has also being researched as a potential therapeutic agent against the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the coronavirus that causes coronavirus disease 2019 (COVID-19). Computer-aided drug design (CADD), Structure and Ligand based Drug Repositioning strategies based on parallel docking methodologies have been widely used for both modern drug development and drug repurposing to find effective treatments against this disease. Quantum mechanics, molecular mechanics, molecular dynamics (MD), and combinations have shown superior performance to other drug design approaches providing an unprecedented opportunity in the rational drug development fields and for the developing of innovative drug repositioning methods. We tested 18 phytochemical small molecule libraries and predicted their synergies in COVID-19 (2019- NCOV), to devise therapeutic strategies, repurpose existing ones in order to counteract highly pathogenic SARS-CoV-2 infection. We anticipate that our geometry hashing driven quantum deep learing similarity approaches which is based on separated pairs of short consecutive matching fragments, can be used for the development of anticoronaviral drug combinations in large scale HTS screenings, and to maximize the safety and efficacy of the Remdesivir, Colchicine and Ursolic acid drugs already known to induce synergy with potential therapeutic value or drug repositioning to COVID-19 patients.
Liver and kidney function in patients with Covid-19 treated with remdesivir
Sylvia van Laar
M De Boer

Sylvia van Laar

and 4 more

January 14, 2021
For the treatment of Covid-19 patients with remdesivir, poor renal- and liver function were both exclusion criteria in randomized clinical trials (RCTs) and contra-indication for treatment. Also, nephrotoxicity and hepatotoxicity are reported as adverse events. We retrospectively reviewed renal- and liver functions of covid-19 patients who received remdesivir in the 15 days after treatment initiation. Approximately 20% of the patient population met RCT exclusion criteria. In total, 11% of the patients had a decrease in estimated glomerular filtration rate larger than 10 ml/min/1.73m2. Also, 25% and 35% had increased alanine transaminase and aspartate transaminase levels, respectively. However, serious adverse events were limited. Therefore, contra-indications based on kidney- and liver function should not be absolute for remdesivir treatment in patients with Covid-19 if these functions are monitored regularly.
Rare case of intra-oral palatal (soft palate) fibro-lipoma
Manit Mandal
Ajay Panchal

Manit Mandal

and 4 more

January 14, 2021
Background: Case study of 30 years male having suspending mass found over upper surface of soft palate hanging in nasopharynx. Methods: After evaluation, patient underwent combined approach (Trans-oral + Endoscopic) excision. Results: Histopathological examination concluded possibility of intra-oral lipoma. Conclusion: Palatal mass (lipoma) requires surgical excision post complete evaluation.
Migratory fish bone in the pharynx, a report of 2 cases
Shuyi Xu
Xiaomin Li

Shuyi Xu

and 6 more

January 14, 2021
Fish bones have a risk of damaging the mucosa when lodged in the pharynx. Fish bones migrated into surrounding tissues is relatively unusual. We present 2 cases of patients who ingested fish bone, which migrated into retropharyngeal space and hypopharynx. All fish bones were removed without complications.
Cytokine induced modulation of ACE2 and TMPRSS2 expression in primary human nasal epi...
Mahnaz Ramezanpour
Harrison Bolt

Mahnaz Ramezanpour

and 6 more

January 14, 2021
Viral entry of severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) via the spike protein enables endocytosis into host cells using the ACE2 receptor and TMPRSS2. The frequent upper respiratory tract symptoms of COVID-19 and the localization of the virus to the nasopharynx, the most common site of swabbing, indicate that the sinonasal mucosa may play an important role in SARS-CoV2 infection and viral replication. This paper investigates the presence of ACE2 Receptor and TMPRESS2 expression in the primary human nasal epithelial cells (HNECs) from Control, CRSsNP, and CRSwNP and maps the expression changes when exposed to Th1, Th2, Th17 associated cytokines. We found that ACE2 and TMPRSS2 expression is higher in control HNECs than CRSwNP HNECs, and that both ACE2 and TMPRSS2 are downregulated further by Th2 cytokines in CRSwNP HNECs. This indicates an immune dysregulated state of CRSwNP mucosa, which normally contributes to a chronic inflammatory state, might support an altered susceptibility to SARS-CoV2 infection and transmission.
Local impedance and ultra-high density 3-dimensional mapping results in improved abla...
Karan Saraf
Nicholas Black

Karan Saraf

and 4 more

January 14, 2021
Introduction Multiple contact-based ablation technologies have been developed to allow real-time judgement of lesion effectiveness; local impedance (LI) guided ablation and the role of ultra-high density (UHD) mapping have not yet been evaluated for cavotricuspid isthmus dependent atrial flutter (CTI-AFL). Methods This non-randomised observational study evaluated patients undergoing CTI-AFL ablation using conventional, contact force (CF) and LI guided strategies. Ablation metrics were collected, and in the LI cohort, the use of UHD mapping for breakthrough was evaluated. Results 30 patients were included, 10 in each group. Mean total ablation time was significantly shorter with LI (3.2±1.3min) vs conventional (5.6±2.7min) and CF (5.7±2.0min, p=0.0042). Time from start of ablation to CTI block was numerically shorter with LI (14.2±8.0min) vs conventional and CF (19.7±14.1 and 22.5±19.1min, p=0.4408). There were no differences in the number of lesions required to achieve block, procedural success, complication rates or recurrence. 15/30 patients did not achieve block following first-pass ablation. UHD mapping rapidly identified breakthrough in the 5 LI patients, including epicardial-endocardial breakthrough (EEB) away from the line. Conclusion The use of LI for real-time assessment of lesion formation resulted in significantly less ablation requirement. UHD mapping rapidly identified breakthrough, including EEB, which would likely have been difficult to identify otherwise and possibly require extensive ablation, contributing towards shortening of time to CTI block with LI.
4- hydroxy-3,5-di-tret-butyl cinnamic acid restores the activity of the hippocampal m...
Dmitry Pozdnyakov

Dmitry Pozdnyakov

January 13, 2021
Background and Purpose: Ischemic stroke remains one of the leading causes of death in the population. In addition, mitochondrial dysfunction is an essential part of the pathogenesis of cerebral ischemia and is a promising pharmacotherapeutic target. Experimental Approach: the work was performed on male Wistar rats, which were simulated cerebral ischemia by irreversible occlusion of the middle cerebral artery. 4-hydroxy-3,5-di-tret-butyl cinnamic acid (25 mg/kg, 50 mg/kg and 100 mg/kg) was injected intraperitoneally for 3 days after ischemia (daily). On the 4th day of the experiment, the changes of rat’s cognitive functions in the Morris water maze test, cellular respiration processes, the activity of the mitochondrial respiratory chain complexes and citrate synthase activity, the intensity of oxidative stress and apoptosis reactions were assessed. Key Results: it was found that the administration of 4-hydroxy-3,5-di-tret-butyl cinnamic acid at doses of 25 mg/kg and 50 mg/kg practically equivalently promotes the restoration of aerobic metabolism reactions and the activity of the mitochondrial respiratory chain complexes, decrease of the intensity of oxidative stress reactions and apoptosis, as well as an increase in the activity of citrate synthase. As a result, the restoration of mitochondrial function in the hippocampal cells contributed to the restoration of the animal’s spatial memory. Conclusion and Implications: a study showed that 4-hydroxy-3,5-di-tret-butyl cinnamic acid at doses of 25 mg/kg and 50 mg/kg has a neuroprotective effect on hippocampal neurons under conditions of permanent occlusion of the middle cerebral artery, realized by restoration of mitochondrial function.
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