3D Computational Modeling of Bleb Initiation Dynamics

Blebbing occurs in cells under high cortical tension when the membrane locally detaches from the actin cortex, resulting in pressure-driven flow of the cytosol and membrane expansion. Some cells use blebs as leading edge protrusions during cell migration, particularly in 3D environments such as a collagen matrix. Blebs can be initiated through either a localized loss of membrane-cortex adhesion or ablation of the cortex in a region. Bleb morphologies resulting from different initiation mechanisms have not been studied in detail, either experimentally or with theoretical models. Additionally, material properties of the cytoplasm, such as elasticity, have been shown to be important for limiting bleb size. A 3D dynamic computational model of the cell is presented that includes mechanics and the interactions of the cytoplasm, the actin cortex, the cell membrane, and the cytoskeleton. The model is used to quantify bleb expansion dynamics and shapes that result from simulations using different initiation mechanisms. The cytoplasm is modeled as a both viscous fluid and as a poroelastic material. Results from model simulations with a viscous fluid cytoplasm model show much broader blebs that expand faster when they are initiated via cortical ablation than when they are initiated by removing only membrane-cortex adhesion. Simulation results using the poroelastic model of the cytoplasm provide qualitatively similar bleb morphologies regardless of the initiation mechanism. Parameter studies on bleb expansion time, cytoplasmic stiffness, and permeability reveal different scaling properties, namely a smaller power-law exponent, in 3D simulations compared to 2D ones.

Pan-European phylogeography of the European roe deer (Capreolus capreolus)

To provide the most comprehensive picture of species phylogeny and phylogeography of European roe deer (Capreolus capreolus), we analysed mtDNA control region (610 bp) of 1469 samples of roe deer from Central and Eastern Europe and included into the analyses additional 1541 mtDNA sequences from GenBank from other regions of the continent. We detected two mtDNA lineages of the species: European and Siberian one (an introgression of C. pygargus mtDNA into C. capreolus). The Siberian lineage was most frequent in eastern part of the continent and declined towards Central Europe. The European lineage contained three clades (Central, Eastern and Western) composed of 2 to 8 subclades, many of which were separated in space. The Western clade appeared to have a discontinuous range from Portugal to Russia. Most of the subclades in the Central and the Eastern clades were under expansion during the Weichselian glacial period before the Last Glacial Maximum (LGM), while the expansion time of the Western clade overlapped with the Eemian interglacial. High genetic diversity of extant roe deer is the result of their survival during the LGM in a large, contiguous range spanning from the Iberian Peninsula to the Caucasus Mts. and in two northern refugia.

Short-Term Outcome of Video Assisted Thoracoscopic Decortication in Empyema Thoracis

Background: Video-assisted thoracoscopic surgical decortication (VATS Decortication) is one of the technique for treating empyema thoracis. Objective: The purpose of the present study was to assess radiologic and functional short-term outcomes of VATS decortication in comparison with open decortication among empyema thoracis patients. Methodology: This comparative type of observational study was done at Department of Thoracic Surgery at National Institute of Diseases of Chest and Hospital (NIDCH), Dhaka, Bangladesh from July 2018 to June 2019 for a period of one year. Patients with empyema thoracis in stage II or III were included. Short-term outcomes were measured according to collection of chest drain tube in post-operative observational days (PODs), post-operative lung expansion, time taken for chest drain tube removal, postoperative hospital stay and post-operative pain (numeric rating scale) observations up to discharge from hospital. Result: A total number of 70 patients were recruited. The mean age was 36.20 ± 12.50 years. In post-operative phase apical chest drain tube collection followed by VATS procedure was found significantly lower than that of open decortication (2nd POD: p= 0.04; 3rd POD: p =0.039). Both the apical (p=0.001) and basal (p=0.039) chest drain tubes were removed earlier in patients with VATS decortication. Again, patients with VATS decortication had to stay less days in post-operative time (p=0.01). The mean post-operative pain scores was significantly higher among the patients underwent open decortication (p<0.001). Conclusion: VATS decortication has shown better outcome in terms of collection of chest drain tube in post- operative days, time taken for chest drain tube removal, post-operative hospital stay and post-operative pain in managing patients with empyema thoracis. Journal of Current and Advance Medical Research, July 2021;8(2):100-105

P–226 Failure of blastocoele expansion within the first two hours post thawing could halve the chances of implantation

Study question The aim of this study was to evaluate the influence of blastocoele re-expansion time of warmed vitrified blastocysts on clinical pregnancy outcome. Summary answer Clinical pregnancy rate was significantly higher after transfer of warmed vitrified blastocysts that were fully expanded within 2 hours post thaw. What is known already The number of blastocysts being vitrified worldwide has increased dramatically over recent years. A combination of factors has led to this including the introduction of vitrification, an increase in freeze-all policies, single embryo transfer and an increase in preimplantation genetic testing. Currently, blastocyst re-expansion after thawing is used to indicate the survival status of the blastocyst and when combined with the morphology of blastocyst can predict its reproductive potential. While time taken for blastocoele re-expansion has been proposed to be a biomarker of viability, its value in clinical practice remains unclear. Study design, size, duration This retrospective study analysed outcomes in patients who had frozen embryo transfers between June-December 2020. 233 embryos were reviewed with time-lapse to assess their blastocoele expansion post-warming and three groups were identified. The first included fully expanded blastocysts post-warming. The second group included partially expanded blastocysts and the third non-expanded blastocysts. In addition, the groups were subcategorised into two further categories depending on whether they took less or more than 2 hours to complete expansion. Participants/materials, setting, methods 233 vitrified/warmed embryos from 216 patients were analysed using time-lapse incubators. The first group included 134 blastocysts, of which 70 were fully expanded within 2 hours and 64 after 2 hours post thaw. The second group had 70 embryos of which 45 expanded partially within 2 hours and 25 after 2 hours. The third had 28 embryos that had no expansion within the first 2 hours (n = 20) or after 2 hours (n = 8). Main results and the role of chance Blastocysts were collapsed by laser prior to vitrification. Single blastocyst transfer was performed for all patients. The mean transferred embryo age was 32.1± 5.5 and the recipient’s was 37.5± 5.9. Fully expanded blastocysts (n = 70) within 2 hours demonstrated a clinical pregnancy rate (CPR) of 57% compared with 38% from those that expanded fully after 2 hours (n = 64) (p = 0.02). Blastocysts with some form of expansion (full or partial) within 2 hours post-warming (n = 115) were associated a significantly higher CPR compared to those expanding after 2 hours (n = 89). The CPR was 55% and 39% respectively (p = 0.02). Embryos that showed no expansion (n = 20) within the first 2 hours post thaw resulted in CPR of 28%. Interestingly, embryos that showed no expansion after 2 hours resulted in no pregnancy. When combining morphology as a selection criterion, expansion within 2 hours of thawing was associated with a CPR of 62.5% for ≥4AB embryos, 50% for BB embryos and 45% for poorer embryos ≤CB.In conclusion, failure of blastocoele expansion post 2 hours reduced by half the chances of clinical pregnancy (p = 0.03). Combination of the degree of re-expansion and embryo morphology is an important predictor tool to improve clinical outcomes in frozen embryo transfers. Limitations, reasons for caution This study uses a small sample size of patients. The data are observational and were retrospectively analysed so unknown confounders could not be assessed. The addition of more cycles and further multivariate analysis, is essential for confirmation of the findings. However, initial results are very reassuring. Wider implications of the findings: The degree of speed of re-expansion post warming should be used as a predictor for prioritisation of embryos for transfer. Owing to these preliminary findings there is rationale for a larger scale study combining other morphological indicators that could further assess implantation indicators and assist patient counselling Trial registration number Not applicable

Time Blast Wave Theory for the Expansion of the Universe

A new theory is presented and tested that time itself is the phenomenon that causes the expansion of the universe and that without expansion, time would simply not be. The model of the theory accurately matches observed cosmological luminosity data consequently accurately describing the observed expansion of the universe. The theory implies that the universe exploded outwards within the dimension of time with all particles expanding from this event within a time blast sphere. Each space dimension is wrapped around the time dimension and every object that is gravitationally separate within the time blast-wave will progress on their own time trajectory of time away from time zero. This has the effect that all objects will expand or move apart as the time sphere expands. We observe distant, and therefore historic, objects on a spiral timeline. We have modelled the theory and shown strong agreement with luminosity observations both at low and high redshift without the need for a cosmological constant thus indicating that the universe is not accelerating in its expansion. The model in fact predicts it is decelerating. The theory also predicts that the unperturbed speed of time expansion will impose a limit on the universe in terms of the fastest speed possible and the speed that light must always travel at. With this limit and as no object can ever be stationary in the time dimension, but that faster and heavier objects will expand less, the theory consequently leads us to explain why special and general relativity occur. Gravity can be explained by the clumping of matter into the dimension of time causing a localised slowing of expansion subsequently causing time dilation and thus resulting in an attractive force with other objects. By this theory, black holes are not singularities but are simply dimples on the time blast wave front.

Vγ9Vδ2 T Cells Concurrently Kill Cancer Cells and Cross-Present Tumor Antigens

The human Vγ9Vδ2 T cell is a unique cell type that holds great potential in immunotherapy of cancer. In particular, the therapeutic potential of this cell type in adoptive cell therapy (ACT) has gained interest. In this regard optimization of in vitro expansion methods and functional characterization is desirable. We show that Vγ9Vδ2 T cells, expanded in vitro with zoledronic acid (Zometa or ZOL) and Interleukin-2 (IL-2), are efficient cancer cell killers with a trend towards increased killing efficacy after prolonged expansion time. Thus, Vγ9Vδ2 T cells expanded for 25 days in vitro killed prostate cancer cells more efficiently than Vγ9Vδ2 T cells expanded for 9 days. These data are supported by phenotype characteristics, showing increased expression of CD56 and NKG2D over time, reaching above 90% positive cells after 25 days of expansion. At the early stage of expansion, we demonstrate that Vγ9Vδ2 T cells are capable of cross-presenting tumor antigens. In this regard, our data show that Vγ9Vδ2 T cells can take up tumor-associated antigens (TAA) gp100, MART-1 and MAGE-A3 - either as long peptide or recombinant protein – and then present TAA-derived peptides on the cell surface in the context of HLA class I molecules, demonstrated by their recognition as targets by peptide-specific CD8 T cells. Importantly, we show that cross-presentation is impaired by the proteasome inhibitor lactacystin. In conclusion, our data indicate that Vγ9Vδ2 T cells are broadly tumor-specific killers with the additional ability to cross-present MHC class I-restricted peptides, thereby inducing or supporting tumor-specific αβTCR CD8 T cell responses. The dual functionality is dynamic during in vitro expansion, yet, both functions are of interest to explore in ACT for cancer therapy.

Autonomous Driving Implementation in an Experimental Environment

Autonomous systems require identifying the environment and it has a long way to go before putting it safely into practice. In autonomous driving systems, the detection of obstacles and traffic lights are of importance as well as lane tracking. In this study, an autonomous driving system is developed and tested in the experimental environment designed for this purpose. In this system, a model vehicle having a camera is used to trace the lanes and avoid obstacles to experimentally study autonomous driving behavior. Convolutional Neural Network models were trained for Lane tracking. For the vehicle to avoid obstacles, corner detection, optical flow, focus of expansion, time to collision, balance calculation, and decision mechanism were created, respectively.

The most recent common ancestor for Y chromosome lived about 3.67 million years ago

The origin of human beings is one of the most important questions in science. A combination of numerous archaeological and genomic analyses has led to the widely accepted opinion that modern humans are the descendants of anatomically modern Homo sapiens that originated in Africa about 200 thousand years ago (KYA). In this study, we reanalysed the mitochondrial DNA and Y chromosome DNA of the 1000 Genomes Project, and found many minority-specific single-nucleotide polymorphisms. Using these polymorphisms, we recalculated the time taken for the evolution of modern humans. Analysis of mitochondrial DNA suggested that the most recent common female ancestor lived about 400 KYA and began to leave Africa about 180 KYA. In contrast, analysis of Y chromosome DNA revealed that the most recent common male ancestor lived about 3.67 million years ago (MYA) and began to migrate out of Africa about 2.05 MYA, a time which is consistent with the expansion time of Homo erectus identified by archaeological research. Based on the findings, we proposed a new migration routes and times of modern human, and speculated that anatomically modern Homo sapiens has been extensively interbred with local archaic human population during their dispersal across the globe.

Medicaid Expansion and Incidence of Kidney Failure among Nonelderly Adults

BackgroundLow-income individuals without health insurance have limited access to health care. Medicaid expansions may reduce kidney failure incidence by improving access to chronic disease care.MethodsUsing a difference-in-differences analysis, we examined the association between Medicaid expansion status under the Affordable Care Act (ACA) and the kidney failure incidence rate among all nonelderly adults, aged 19–64 years, in the United States, from 2012 through 2018. We compared changes in kidney failure incidence in states that implemented Medicaid expansions with concurrent changes in nonexpansion states during pre-expansion, early postexpansion (years 2 and 3 postexpansion), and later postexpansion (years 4 and 5 postexpansion).ResultsThe unadjusted kidney failure incidence rate increased in the early years of the study period in both expansion and nonexpansion states before stabilizing. After adjustment for population sociodemographic characteristics, Medicaid expansion status was associated with 2.20 fewer incident cases of kidney failure per million adults per quarter in the early postexpansion period (95% CI, −3.89 to −0.51) compared with nonexpansion status, a 3.07% relative reduction (95% CI, −5.43% to −0.72%). In the later postexpansion period, Medicaid expansion status was not associated with a statistically significant change in kidney failure incidence (−0.56 cases per million per quarter; 95% CI, −2.71 to 1.58) compared with nonexpansion status and the pre-expansion time period.ConclusionsThe ACA Medicaid expansion was associated with an initial reduction in kidney failure incidence among the entire, nonelderly, adult population in the United States; but the changes did not persist in the later postexpansion period. Further study is needed to determine the long-term association between Medicaid expansion and changes in kidney failure incidence.