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We performed a comparative study of the colony-forming ability and the number of residual foci of DNA repair proteins in cultured human lung fibroblasts (MRC-5 cell line) after exposure to subpicosecond beams of accelerated electrons with an energy of 3.6 MeV and quasi-continuous radiation (accelerated electrons with an energy of 4 MeV and X-rays). The yield of damages causing reproductive cell death after pulsed subpicosecond radiation exposure was higher by ~1.8 times than after quasi-continuous radiation exposure. The quantitative yield of residual γH2AX foci (phosphorylated H2AX histone, a protein marker of DNA double breaks) in cells irradiated with subpicosecond beams of accelerated electrons was shown to be ~2.0- 2.5-fold higher than in cells irradiated with quasi-continuous beams of accelerated electrons. [ABSTRACT FROM AUTHOR]

AREAL (Advanced Research Electron Accelerator Laboratory) is an electron linear accelerator with a laser driven RF gun constructed at CANDLE Synchrotron Research Institute. After the successful operation of the gun section at 5 MeV, a program of facility energy growth up to 50 MeV has been launched, which includes the construction of two advanced experimental stations for the generation of middle infrared and THz radiation. This paper presents the design of these stations and gives the characteristics of expected radiation based on numerical and theoretical studies. [ABSTRACT FROM AUTHOR]

This paper reports the formation of structural defects in the lattice of silicon (n-Si) single crystals, as a result of irradiation by different intensities and pulses of electrons. The samples were studied by means of Hall effect measurements of electro-physical parameters (specifically the concentration of the main charge carriers) as a function of temperature and radiation dose. The role of the radiation current density (pulse height) is discussed, which gives rise to a peculiar behavior in the electrical-physical properties of n-Si. In particular, thermal processes are found not to develop, due to the ultrafast (pulse duration in the range 10−12-10−13s) nature of the incident radiation, which causes an almost “pure” energy interaction to occur between the radiation and the atoms within the crystal, and the formation of cluster defects. A scheme for the time-scale of the formation of these radiation defects is presented. From the dose and temperature dependences of the concentration of main charge carriers, the radiation defects introduction rates were determined. [ABSTRACT FROM AUTHOR]

The paper investigates the fluctuations of the rate of enzymatic reaction with theoretical estimations and analysis. It was shown that combined analysis of the reaction rate and its dispersion allows obtaining new information on the reaction through the comparison of the theoretical formulas and experimental data. The latter includes the rate constants of enzyme-substrate complex decay and maximal enzyme concentration. [ABSTRACT FROM AUTHOR]

We are planning to construct a 3 GeV synchrotron light source in the Republic of Armenia called Center for the Advancement of Natural Discoveries using light emission—CANDLE. The purpose of the machine is to produce high flux and high brightness photon beams from bends and insertion devices in the soft and hard x-ray spectrum range from 1 to 50 keV. The main elements of the light source are an S-band linac, a full energy booster, and a 16-cell double bend achromatic storage ring. We will discuss the main parameters of the machine, the insertion devices, and the preliminary beamlines instrumentation. © 2002 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Temporally modulated electron beams have a wide array of applications ranging from the generation of coherently enhanced electromagnetic radiation to the resonant excitation of electromagnetic wakefields in advanced-accelerator concepts. Likewise producing low-energy ultrashort microbunches could be useful for ultrafast electron diffraction and new accelerator-based light-source concepts. In this Letter we propose and experimentally demonstrate a passive microbunching technique capable of forming a picosecond bunch train at ~6 MeV. The method relies on the excitation of electromagnetic wakefields as the beam propagates through a dielectric-lined waveguide. Owing to the nonultrarelativistic nature of the beam, the induced energy modulation eventually converts into a density modulation as the beam travels in a following free-space drift. The modulated beam is further accelerated to ~20 MeV while preserving the imparted density modulation. [ABSTRACT FROM AUTHOR]

Introduction: The aim of the study was to estimate the influence of a simple kidney cyst on kidney function and to determine indications for surgical treatment., Materials and Methods: In this prospective cohort study, we analyze data on 109 patients who sought counseling with a simple kidney cyst. Patients with solitary cyst of the right or left kidney, grade I-IIF according to the Bosniak classification, were included. Split glomerular filtration rate (sGFR) was calculated. The maximum size of the cyst, single kidney volumes (SKV) and the volume of the lost (atrophied) parenchyma were estimated with computed tomography (CT) scan of the urinary tract with contrast., Results: The average difference between the sGFR of a healthy and affected kidney cyst was 11 [8.70; 13.44] ml/min, which is a statistically significant value ( p  = 0.001). Correlation analysis revealed a statistically significant relationship between the proportion of lost parenchyma and the maximum cyst size: p  = 0.37 with 95% CI [0.20; 0.52] ( p  = 0). A multivariate logistic regression model showed that a statistically significant factor influencing the likelihood of a significant decrease in sGFR is the percentage of lost kidney parenchyma (OR = 1.13; p  = 0)., Conclusion: The growth of kidney cyst causes atrophy of the renal parenchyma and a decrease in the sGFR of the affected kidney. An increase in the volume of the atrophied parenchyma leads to a decrease in the sGFR of the affected kidney., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Malkhasyan, Makhmudov, Gilfanov, Semenyakin, Sukhikh, Grigoryan and Pushkar.)

Application of laser-generated electron beams in radiotherapy is a recent development. Accordingly, mechanisms of biological response to radiation damage need to be investigated. In this study, telomere length (TL) as endpoint of genetic damage was analyzed in human blood cells (leukocytes) and K562 leukemic cells irradiated with laser-generated ultrashort electron beam. Metaphases and interphases were analyzed in quantitative fluorescence in situ hybridization (Q-FISH) to assess TL. TLs were shortened compared to non-irradiated controls in both settings (metaphase and interphase) after irradiation with 0.5, 1.5, and 3.0 Gy in blood leukocytes. Radiation also caused a significant TL shortening detectable in the interphase of K562 cells. Overall, a negative correlation between TL and radiation doses was observed in normal and leukemic cells in a dose-dependent manner. K562 cells were more sensitive than normal blood cells to increasing doses of ultrashort electron beam radiation. As telomere shortening leads to genome instability and cell death, the results obtained confirm the suitability of this biomarker for assessing genotoxic effects of accelerated electrons for their further use in radiation therapy. Observed differences in TL shortening between normal and K562 cells provide an opportunity for further development of optimal radiation parameters to reduce side effects in normal cells during radiotherapy.

Retrograde intrarenal surgery (RIRS) is a type of endoscopic intervention on the kidneys performed using a semi-rigid or flexible fiber optic endoscope. RIRS is recommended by national clinical guidelines for stone management sized up to 20 mm. However, like any other surgical intervention, RIRS is associated with the risk of complications. Complications affect the patients quality of life, and cause additional costs determined by prolonged hospital stay and subsequent treatment. This systematic review is devoted to the complications of RIRS, methods of their prevention and treatment, which should make possible to increase the effectiveness and safety of care for patients with urolithiasis.

Introduction and Hypothesis: The aim of this study is to evaluate the efficacy and safety of autologous fascial slings (AFS) compared with other surgical methods for female stress urinary incontinence (SUI) treatment., Methods: The search was performed on studies published before September 2023 to identify articles assessing the effectiveness and safety of AFS compared with other surgical methods in female SUI. Inclusion criteria were randomized controlled trials (RCTs) and adult women with SUI. Exclusion criteria were other urinary incontinence types, combined pharmacological treatment, pregnancy, and lactation. This systematic review was conducted according to the Population, Intervention, Comparison, and Outcome framework, Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 checklist, and was registered in the Prospective Register of Systematic Reviews., Results: Twenty RCTs were included in the systematic review and 10 RCTs in the meta-analysis. Comparison between AFS and synthetic midurethral slings (SMUS) did not show any statistically significant differences in the cure rate, frequency of urinary retention, or self-catheterization. SMUS showed more long-term postoperative complications (RR = 0.12, 95% CI: 0.03 to 0.50, p = 0.004), AFS had more in de novo urgency cases: (RR = 2.84, 95% CI: 1.13 to 7.10, p = 0.03). Operation time of SMUS was lower: (RR = 2.87, 95% CI: 2.56 to 3.19, p < 0.00001, I 2  = 97%). SMUS showed significantly lower hospital stay duration: (RR = 1.92, 95% CI: 1.44 to 2.41, p < 0.00001)., Conclusions: In this systematic review and meta-analysis, autologous slings demonstrated the same efficacy in comparison with SMUS in the management of SUI in women. AFS showed lower incidence of long-term postoperative complications. SMUS demonstrated lower operation time, hospital stay and de novo urgency., (© 2024. The International Urogynecological Association.)

Aim: The aim of the observational cohort study is to study and evaluate the efficiency of the drug Adenoprosin in combination with other drugs in comparison with monotherapy., Materials and Methods: Data from 6,442 patients at 221 medical institutions in 39 cities from November 2020 to December 2022 were analyzed. The drug Adenoprosin in the form of rectal suppositories was prescribed as monotherapy in group I, while patients in group II received Adenoprosin in a combination with other drugs. The efficacy of treatment was assessed using uroflowmetry data, prostate volume, postvoid residual volume and validated scales (NIH-CPSI, IIEF-5, IPSS, QoL)., Results: The diagnosis was validated in 6375 cases, including BPH (n=1498), chronic prostatitis (CP; n=3060), and in combination of both disorders (n=1817). A total of 3580 patients received Adenoprosin as monotherapy, while 2761 received combination therapy. In most cases, a combination therapy was prescribed in case of more severe disease. In patients with BPH, positive changes after treatment were noted in favor of group I according to change in postvoid residual volume (p<0.001) and prostate volume (p<0.001). Combination therapy demonstrated significant positive changes compared with monotherapy when assessing NIH-CPSI scores (p=0.005), IPSS scores (p<0.001) and the mean maximum urine flow rate (Qmax; p<0.001). Qmax increased significantly in both groups (from 14 ml/s to 17 ml/s in group I and from 12 ml/s to 14 ml/s in group II)., Conclusion: Treatment of BPH, CP and their combination is a complex clinical task. The multiple nature of complaints often dictates the need for simultaneous administration of two or more drugs. Combination therapy involves the use of multiple therapeutic strategies to treat different aspects of BPH and CP. In patients with BPH, a combination therapy has been shown to be more effective than monotherapy with either class of drugs, as it reduces the risk of disease progression, acute urinary retention, and the need for surgery. However, combination therapy should be considered on an individual basis, taking into account symptoms, prostate size and overall health. There is no universal treatment method for BPH suitable for any patient. The treatment strategy should be chosen individually, considering all medical and social factors. All of the above applies to a large extent to the treatment of CP and CP + BPH. According to our results, Adenoprosin demonstrated efficacy both as monotherapy and in combination with other traditional drugs in the treatment of men with lower urinary tract symptoms.

Introduction and Hypothesis: The objective of this study was to evaluate the efficacy and safety of different adjustable slings compared to other surgical methods for the treatment of stress urinary incontinence (SUI) among women., Methods: The inclusion criteria were as follows: randomized controlled trials (RCTs) and non-RCTs assessing adult women with SUI. The exclusion criteria were as follows: other types of urinary incontinence, studies that combined conservative interventions and pharmacological treatment, pregnant and lactating patients. Databases were searched up to November 2022 to identify articles evaluating the effectiveness and safety of different adjustable slings compared to other surgical methods for the treatment of SUI among women. The systematic review was conducted in accordance with the PRISMA 2020 checklist and registered in PROSPERO. Risk-of-bias assessment tools recommended by the Cochrane Society were used to evaluate the risk of bias in the included studies., Results: Eighteen clinical trials were included in this systematic review, and 11 studies were included in the meta-analysis. Fourteen studies were RCTs, and four were retrospective studies. Only RCTs were included in the meta-analyses. There was no statistically significant difference in the objective cure rate, subjective cure rate, or long-term postoperative complication rate between Ajust single-incision mini-slings (SIMS) and standard mid-urethral slings (SMUS) or MiniArc SIMS. However, the operation time in the adjustable SIMS group was significantly shorter (RR = -4.20, 95% CI: [-7.51, -0.89], p = 0.01)., Conclusions: This systematic review and meta-analysis revealed that adjustable SIMS is equally effective when compared with SMUS for the treatment of SUI among women. Moreover, the operation time for the adjustable SIMS was shorter. However, additional well-designed studies with standard outcome measures and complete follow-up periods will help to increase confidence in the choice of different options for treating SUI among women., (© 2023. The International Urogynecological Association.)

Background: Urinary incontinence (UI) is a urological problem in women. Currently, suburethral slings are the standard of surgical treatment for stress UI in the female population., Objective: To prove the feasibility of an operating technique using suburethral adjustment-controlled tape (SACT) placement., Design, Setting, and Participants: A single-center comparative randomized controlled trial included patients randomized according to the CONSORT checklist from April to October 2018 and from November 2018 to April 2019. The inclusion criteria were women from 21 to 81 yr, stress and mixed UI forms, and positive cough test. The exclusion criteria were pregnancy, lactation, neurogenic bladder dysfunction, recurrent forms of UI, radiation therapy and pelvic surgery in anamnesis, genital prolapse (Pelvic Organ Prolapse Quantification system >2), urinary infection, and obstructive urination., Intervention: The first group (50 patients) was using synthetic SACT and the second group (75 patients) a transobturator tape (TOT) midurethral sling (MUS)., Outcome Measurements and Statistical Analysis: Subjective efficacy of 96% was established in group 1 and 86% in group 2, with a median follow-up of 12 mo. According to gynecological examination results, the objective surgical treatment efficiency was 96% in group 1 and 90.7% in group 2. This statistically significant indicator was evaluated in each group. However, when comparing both groups, no statistical difference was revealed. According to urodynamic studies, 1 mo after surgery in group 1, terminal and phase detrusor overactivity signs were 18% (n = 9) and 12% (n = 6), respectively. In group 2, these were 14.7% (n = 11) and 12% (n = 9), respectively., Results and Limitations: The block approach was used to randomize patients into groups. A total of 125 patients (50 in the main group and 75 in the control group) were analyzed., Conclusions: Our results prove the efficacy and safety of SACT in treating UI in women. The subjective and objective effectiveness results of treating patients in the study group show the possibility of using SACT in the same row with TOT MUS., Patient Summary: Our purpose was to standardize the surgery stage for urinary incontinence, and evaluate the effectiveness and safety of suburethral adjustment-controlled tape placement. We analyzed women with urinary incontinence and used two different surgical methods. Our results prove the efficacy and safety of suburethral adjustment-controlled tape in treating urinary incontinence in women., (Copyright © 2021 European Association of Urology. Published by Elsevier B.V. All rights reserved.)

Anemia is a commonly observed consequence of whole-body exposure to a dose of X-ray or gamma irradiation of the order of the mean lethal dose in mammals, and it is an important factor for the determination of the survival of animals. The aim of this study was to unravel the effect of laser-driven ultrashort pulsed electron beam (UPEB) irradiation on the process of erythropoiesis and the redox state in the organism. Wistar rats were exposed to laser-driven UPEB irradiation, after which the level of oxidative stress and the activities of different antioxidant enzymes, as well as blood smears, bone marrow imprints and sections, erythroblastic islets, hemoglobin and hematocrit, hepatic iron, DNA, and erythropoietin levels, were assessed on the 1st, 3rd, 7th, 14th, and 28th days after irradiation. Despite the fact that laser-driven UPEB irradiation requires quite low doses and repetition rates to achieve the LD 50 in rats, our findings suggest that whole-body exposure with this new type of irradiation causes relatively mild anemia in rats, with subsequent fast recovery up to the 28th day. Moreover, this novel type of irradiation causes highly intense processes of oxidative stress, which, despite being relatively extinguished, did not reach the physiologically stable level even at the 28th day after irradiation due to the violations in the antioxidant system of the organism.

Background: Bladder pain syndrome/interstitial cystitis (BPS/IC) is a persistent pain perceived in the urinary bladder region, accompanied by at least one symptom, such as pain worsening with bladder filling and daytime or nighttime urinary frequency without any proven infection or obvious pathology. The aim of this study is to evaluate the efficacy and safety of pentosan polysulfate (PPS) in patients with BPS/IC., Methods: Systematic search was performed by PRISMA checklist. Electronic databases, including PubMed and Cochrane library, were checked until 2021 using keywords: 'pentosan polysulfate', 'pain syndrome', 'interstitial cystitis', and bibliography of relevant papers was checked., Inclusion Criteria: Patients with confirmed diagnosis of BPS/IC and cystoscopy criteria - Hunner's lesions. Exclusion criteria included hypersensitivity, pregnancy, lactation, and oral therapy for BPS/IC in the period of 1 month before the study and abstracts or unpublished papers., Results: In total, 13 clinical trials were included in systematic review and 7 were included in meta-analysis. Studies evaluated the effectiveness and safety of oral PPS versus placebo or other treatment options. In the first meta-analysis, three studies compared oral PPS with placebo: [relative risk (RR) = 2.07, 95% confidence interval (CI): 1.37-3.13, p  = 0.0006]. The second meta-analysis of two studies compared oral PPS with another treatment options (intravesical liposome and CyA): (RR = 0.44, 95% CI: 0.10-1.93, p  = 0.28). The third meta-analysis of two studies included intravesical regimen of PPS compared with intravesical placebo: (RR = 1.09, 95% CI: 0.54-2.22, p  = 0.80). The majority of studies do not report any particular serious side effects., Conclusion: PPS treatment has a statistically significant effect over placebo on the subjective improvement of patients with BPS/IC. There was no difference between PPS and other treatment options. Intravesical regimen of PPS had no significant impact on response rates. None of included studies reported severe side effects after intervention., Competing Interests: Conflict of interest statement: The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© The Author(s), 2022.)

Introduction and Hypothesis: The objective was to evaluate the efficacy and safety of bulking agents compared with surgical methods for female stress urinary incontinence., Methods: Inclusion and exclusion criteria: women with stress urinary incontinence. Bulking agents versus any surgical treatment as a comparison. Patients with other types of incontinence and treatment were excluded. Electronic databases (PubMed, MEDLINE, and the Cochrane Library) were searched from 2000 until 2021 to identify articles evaluating the effectiveness and safety of urethral bulking agents versus surgical methods. Risk-of-bias assessment tools recommended by the Cochrane Society were used to evaluate the risk of bias in the studies included., Results: Six studies were included in the quantitative synthesis for a total of 710 patients. Our systematic review and meta-analysis showed that bulking agents are less effective than surgical procedures according to subjective improvement after treatment (RR = 0.70, 95% CI: 0.53 to 0.92, p = 0.01). There was no statistically significant difference between these two methods with regard to complications after the intervention (RR = 1.30, 95% CI: 0.30 to 5.66, p = 0.73)., Conclusion: The main limitation of this systematic review and meta-analysis was the absence of a common objective outcome measure to evaluate effectiveness. However, it shows that bulking agents are less effective than surgical procedures in subjective improvement. Safety analysis showed no significant difference between these methods. Hence, we believe that the first and final surgery is considered to be the best., (© 2021. The International Urogynecological Association.)

Modern ultrasound (US) imaging is increasing its clinical impact, particularly with the introduction of US-based quantitative imaging biomarkers. Continued development and validation of such novel imaging approaches requires imaging phantoms that recapitulate the underlying anatomy and pathology of interest. However, current US phantom designs are generally too simplistic to emulate the structure and variability of the human body. Therefore, there is a need to create a platform that is capable of generating well-characterized phantoms that can mimic the basic anatomical, functional, and mechanical properties of native tissues and pathologies. Using a 3D-printing technique based on stereolithography, we fabricated US phantoms using soft materials in a single fabrication session, without the need for material casting or back-filling. With this technique, we induced variable levels of stable US backscatter in our printed materials in anatomically relevant 3D patterns. Additionally, we controlled phantom stiffness from 7 to >120 kPa at the voxel level to generate isotropic and anisotropic phantoms for elasticity imaging. Lastly, we demonstrated the fabrication of channels with diameters as small as 60 micrometers and with complex geometry (e.g., tortuosity) capable of supporting blood-mimicking fluid flow. Collectively, these results show that projection-based stereolithography allows for customizable fabrication of complex US phantoms., Competing Interests: The authors have declared that no competing interests exist.

Recently, a new technology of low-energy ultrashort-pulsed electron beam (UPEB) accelerators has been developed opening new directions for radiobiology and biomedical research. The purpose of this study was to reveal the lethal dose, LD50 (lethal dose, 50%) delivered by low-energy UPEB whole-body exposure on an organismal level. Wistar rats were exposed to low-energy UPEB whole-body irradiation with different doses and pulse repetition rates to find the LD50 and in silico computer simulations were performed to conduct numerical dose calculations. Survival rate, body weight and water consumption were monitored over the 30-day observation period postirradiation. The LD50 was observed after a 2 Gy dose and pulse repetition rate of 2 Hz. In this group, 50% of the animals survived 30 days postirradiation. The groups of animals exposed to low-energy UPEB radiation at higher doses and pulse repetition rates demonstrated higher mortality rates. We demonstrated that the LD50 dose for the low-energy UPEB whole body irradiation in Wistar rats corresponds to 2 Gy with a pulse repetition rate of 2 Hz. Moreover, we showed that the pulse repetition rate is a very important parameter in the experiments with UPEB and should be assessed in the experiments with such kind of novel irradiation sources., (©2021 by Radiation Research Society. All rights of reproduction in any form reserved.)

The development of new laser-driven electron linear accelerators, providing unique ultrashort pulsed electron beams (UPEBs) with low repetition rates, opens new opportunities for radiotherapy and new fronts for radiobiological research in general. Considering the growing interest in the application of UPEBs in radiation biology and medicine, the aim of this study was to reveal the changes in immune system in response to low-energy laser-driven UPEB whole-body irradiation in rodents. Forty male albino Wistar rats were exposed to laser-driven UPEB irradiation, after which different immunological parameters were studied on the 1st, 3rd, 7th, 14th, and 28th day after irradiation. According to the results, this type of irradiation induces alterations in the rat immune system, particularly by increasing the production of pro- and anti-inflammatory cytokines and elevating the DNA damage rate. Moreover, such an immune response reaches its maximal levels on the third day after laser-driven UPEB whole-body irradiation, showing partial recovery on subsequent days with a total recovery on the 28th day. The results of this study provide valuable insight into the effect of laser-driven UPEB whole-body irradiation on the immune system of the animals and support further animal experiments on the role of this novel type of irradiation.

Recently developed biofabrication technologies are enabling the production of three-dimensional engineered tissues containing vascular networks which can deliver oxygen and nutrients across large tissue volumes. Tissues at this scale show promise for eventual regenerative medicine applications; however, the implantation and integration of these constructs in vivo remains poorly studied. Here, we introduce a surgical model for implantation and direct in-line vascular connection of 3D printed hydrogels in a porcine arteriovenous shunt configuration. Utilizing perfusable poly(ethylene glycol) diacrylate (PEGDA) hydrogels fabricated through projection stereolithography, we first optimized the implantation procedure in deceased piglets. Subsequently, we utilized the arteriovenous shunt model to evaluate blood flow through implanted PEGDA hydrogels in non-survivable studies. Connections between the host femoral artery and vein were robust and the patterned vascular channels withstood arterial pressure, permitting blood flow for 6 h. Our study demonstrates rapid prototyping of a biocompatible and perfusable hydrogel that can be implanted in vivo as a porcine arteriovenous shunt, suggesting a viable surgical approach for in-line implantation of bioprinted tissues, along with design considerations for future in vivo studies. We further envision that this surgical model may be broadly applicable for assessing whether biomaterials optimized for 3D printing and cell function can also withstand vascular cannulation and arterial blood pressure. This provides a crucial step toward generated transplantable engineered organs, demonstrating successful implantation of engineered tissues within host vasculature., Competing Interests: JSM and BG are cofounders of and hold an equity stake in the startup company Volumetric, Inc. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Galván, Paulsen, Kinstlinger, Marini, Didelija, Yoeli, Grigoryan and Miller.)

As engineered tissues progress toward therapeutically relevant length scales and cell densities, it is critical to deliver oxygen and nutrients throughout the tissue volume via perfusion through vascular networks. Furthermore, seeding of endothelial cells within these networks can recapitulate the barrier function and vascular physiology of native blood vessels. In this protocol, we describe how to fabricate and assemble customizable open-source tissue perfusion chambers and catheterize tissue constructs inside them. Human endothelial cells are seeded along the lumenal surfaces of the tissue constructs, which are subsequently connected to fluid pumping equipment. The protocol is agnostic with respect to biofabrication methodology as well as cell and material composition, and thus can enable a wide variety of experimental designs. It takes ~14 h over the course of 3 d to prepare perfusion chambers and begin a perfusion experiment. We envision that this protocol will facilitate the adoption and standardization of perfusion tissue culture methods across the fields of biomaterials and tissue engineering.

As a 3D bioprinting technique, hydrogel stereolithography has historically been limited in its ability to capture the spatial heterogeneity that permeates mammalian tissues and dictates structure-function relationships. This limitation stems directly from the difficulty of preventing unwanted material mixing when switching between different liquid bioinks. Accordingly, we present the development, characterization, and application of a multi-material stereolithography bioprinter that provides controlled material selection, yields precise regional feature alignment, and minimizes bioink mixing. Fluorescent tracers were first used to highlight the broad design freedoms afforded by this fabrication strategy, complemented by morphometric image analysis to validate architectural fidelity. To evaluate the bioactivity of printed gels, 344SQ lung adenocarcinoma cells were printed in a 3D core/shell architecture. These cells exhibited native phenotypic behavior as evidenced by apparent proliferation and formation of spherical multicellular aggregates. Cells were also printed as pre-formed multicellular aggregates, which appropriately developed invasive protrusions in response to hTGF-β1. Finally, we constructed a simplified model of intratumoral heterogeneity with two separate sub-populations of 344SQ cells, which together grew over 14 days to form a dense regional interface. Together, these studies highlight the potential of multi-material stereolithography to probe heterotypic interactions between distinct cell types in tissue-specific microenvironments.

Introduction: This case-control trial investigates the prevalence of COL3A1 and COL1A1 gene polymorphisms in female patients suffering pelvic organ prolapse (POP) and stress urinary incontinence (SUI) in comparison with controls., Material and Methods: Inclusion criteria were having one or more risk factors for SUI and POP. Exclusion criteria were hereditary connective tissue diseases as well as surgeries for POP/SUI for the control group. The rs1800255 polymorphism in COL3A1 gene was considered as a local substitution of guanine (G) for adenine (A). The rs1800012 polymorphism in COL1A1 gene was considered as a local substitution of guanine (G) for thymine (T). Genotyping was performed by Sanger sequencing method, followed by estimation of sensitivity and specificity for POP and SUI., Results: Fifty-two patients with POP and SUI (mean age 64.4 years) and 21 women were included in the control group (mean age 63.2 years). Homozygous genotype (AA) in COL3A1 was found in 10% of patients suffering from POP or SUI. No women in the control group had this genotype. The single nucleotide polymorphism (SNP) had high specificity (1.0) for POP/SUI, but low sensitivity (0.1). Heterozygous genotype (AG) in COL3A1 had a sensitivity equal to 0.47 and specificity of 0.62. Homozygous genotype (TT) in COL1A1 was found in only 2% of patients with POP/SUI, but was not found in controls. Heterozygous genotype (TG) in COL1A1 has sensitivity equal to 0.25 and specificity of 0.74., Conclusions: POP/SUI patients have specific SNPs in COL1A1 and COL3A1 sequenced by Sanger method., Competing Interests: The authors declare no conflicts of interest., (Copyright by Polish Urological Association.)

Laser-driven accelerators allow to generate ultrashort (from femto- to picoseconds) high peak dose-rate (up to tens of GGy/s) accelerated particle beams. However, the radiobiological effects of ultrashort pulsed irradiation are still poorly studied. The aim of this work was to compare the formation and elimination of γH2AX and 53BP1 foci (well known markers for DNA double-strand breaks (DSBs)) in Hela cells exposed to ultrashort pulsed electron beams generated by Advanced Research Electron Accelerator Laboratory (AREAL) accelerator (electron energy 3.6 MeV, pulse duration 450 fs, pulse repetition rates 2 or 20 Hz) and quasi-continuous radiation generated by Varian accelerator (electron energy 4 MeV) at doses of 250-1000 mGy. Additionally, a study on the dose-response relationships of changes in the number of residual γH2AX foci in HeLa and A549 cells 24 h after irradiation at doses of 500-10,000 mGy were performed. We found no statistically significant differences in γH2AX and 53BP1 foci yields at 1 h after exposure to 2 Hz ultrashort pulse vs. quasi-continuous radiations. In contrast, 20 Hz ultrashort pulse irradiation resulted in 1.27-fold higher foci yields as compared to the quasi-continuous one. After 24 h of pulse irradiation at doses of 500-10,000 mGy the number of residual γH2AX foci in Hela and A549 cells was 1.7-2.9 times higher compared to that of quasi-continuous irradiation. Overall, the obtained results suggest the slower repair rate for DSBs induced by ultrashort pulse irradiation in comparison to DSBs induced by quasi-continuous irradiation.

Spatial patterns of gene expression in living organisms orchestrate cell decisions in development, homeostasis, and disease. However, most methods for reconstructing gene patterning in 3D cell culture and artificial tissues are restricted by patterning depth and scale. We introduce a depth- and scale-flexible method to direct volumetric gene expression patterning in 3D artificial tissues, which we call "heat exchangers for actuation of transcription" (HEAT). This approach leverages fluid-based heat transfer from printed networks in the tissues to activate heat-inducible transgenes expressed by embedded cells. We show that gene expression patterning can be tuned both spatially and dynamically by varying channel network architecture, fluid temperature, fluid flow direction, and stimulation timing in a user-defined manner and maintained in vivo. We apply this approach to activate the 3D positional expression of Wnt ligands and Wnt/β-catenin pathway regulators, which are major regulators of development, homeostasis, regeneration, and cancer throughout the animal kingdom., (Copyright © 2020 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC).)

The effects of 50-150 gray electron-beam irradiation on the biofilm-formation ability and cell surface hydrophobicity of the commercial strain, Lactobacillus acidophilus DDS®-1, from Lacto-G (a marketed synbiotic formulation) and the putative probiotic, L. rhamnosus Vahe, were evaluated. No significant changes in cell surface hydrophobicity were found after irradiation, while increases in biofilm-formation abilities were documented for both investigated microorganisms 0.22 ± 0.03 vs. 0.149 ± 0.02 (L. rhamnosus Vahe, 150 Gy) and 0.218 ± 0.021 vs. 0.17 ± 0.012 (L. acidophilus DDS®-1, 150 Gy). Given this, the use of electron-beam irradiation (50-100 Gy) for the treatment of L. rhamnosus Vahe and L. acidophilus DDS®-1 cells may be considered in product sterilization, quality improvement, and packaging practices.

Rapidly evolving laser technologies have led to the development of laser-generated particle accelerators as an alternative to conventional facilities. However, the radiobiological characteristics need to be determined to enhance their applications in biology and medicine. In this study, the radiobiological effects of ultrashort pulsed electron beam (UPEB) and X-ray radiation in human lung fibroblasts (MRC-5 cell line) exposed to doses of 0.1, 0.5, and 1 Gy are compared. The changes of γH2AX foci number as a marker of DNA double-strand breaks (DSBs) were analyzed. In addition, the micronuclei induction and cell death via apoptosis were studied. We found that the biological action of UPEB-radiation compared to X-rays was characterized by significantly slower γH2AX foci elimination (with a dose of 1 Gy) and strong apoptosis induction (with doses of 0.5 and 1.0 Gy), accompanied by a slight increase in micronuclei formation (dose of 1 Gy). Our data suggest that UPEB radiation produces more complex DNA damage than X-ray radiation, leading to cell death rather than cytogenetic disturbance.

Background: Environmental risk factors have been shown to alter DNA copy number variations (CNVs). Recently, CNVs have been described to arise after low-dose ionizing radiation in vitro and in vivo. Development of cost- and size-effective laser-driven electron accelerators (LDEAs), capable to deliver high energy beams in pico- or femtosecond durations requires examination of their biological effects. Here we studied in vitro impact of LDEAs radiation on known CNV hotspots in human peripheral blood lymphocytes on single cell level., Results: Here CNVs in chromosomal regions 1p31.1, 7q11.22, 9q21.3, 10q21.1 and 16q23.1 earlier reported to be sensitive to ionizing radiation were analyzed using molecular cytogenetics. Irradiation of cells with 0.5, 1.5 and 3.0 Gy significantly increased signal intensities in all analyzed chromosomal regions compared to controls. The latter is suggested to be due to radiation-induced duplication or amplification of CNV stretches. As significantly lower gains in mean fluorescence intensities were observed only for chromosomal locus 1p31.1 (after irradiation with 3.0 Gy variant sensitivites of different loci to LDEA is suggested. Negative correlation was found between fluorescence intensities and chromosome size ( r  = - 0.783, p  < 0.001) in cells exposed to 3.0 Gy irradiation and between fluorescence intensities and gene density ( r  = - 0.475, p  < 0.05) in cells exposed to 0.5 Gy irradiation., Conclusions: In this study we demonstrated that irradiation with laser-driven electron bunches can induce molecular-cytogenetically visible CNVs in human blood leukocytes in vitro. These CNVs occur most likely due to duplications or amplification and tend to inversely correlate with chromosome size and gene density. CNVs can last in cell population as stable chromosomal changes for several days after radiation exposure; therefore this endpoint can be used for characterization of genetic effects of accelerated electrons. These findings should be complemented with other studies and implementation of more sophisticated approaches for CNVs analysis., Competing Interests: Competing interestsThe authors declare that they have no competing interests.

Solid organs transport fluids through distinct vascular networks that are biophysically and biochemically entangled, creating complex three-dimensional (3D) transport regimes that have remained difficult to produce and study. We establish intravascular and multivascular design freedoms with photopolymerizable hydrogels by using food dye additives as biocompatible yet potent photoabsorbers for projection stereolithography. We demonstrate monolithic transparent hydrogels, produced in minutes, comprising efficient intravascular 3D fluid mixers and functional bicuspid valves. We further elaborate entangled vascular networks from space-filling mathematical topologies and explore the oxygenation and flow of human red blood cells during tidal ventilation and distension of a proximate airway. In addition, we deploy structured biodegradable hydrogel carriers in a rodent model of chronic liver injury to highlight the potential translational utility of this materials innovation., (Copyright © 2019 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.)

Laser-generated electron beams are distinguished from conventional accelerated particles by ultrashort beam pulses in the femtoseconds to picoseconds duration range, and their application may elucidate primary radiobiological effects. The aim of the present study was to determine the dose-rate effect of laser-generated ultrashort pulses of 4 MeV electron beam radiation on DNA damage and repair in human cells. The dose rate was increased via changing the pulse repetition frequency, without increasing the electron energy. The human chronic myeloid leukemia K-562 cell line was used to estimate the DNA damage and repair after irradiation, via the comet assay. A distribution analysis of the DNA damage was performed. The same mean level of initial DNA damages was observed at low (3.6 Gy/min) and high (36 Gy/min) dose-rate irradiation. In the case of low-dose-rate irradiation, the detected DNA damages were completely repairable, whereas the high-dose-rate irradiation demonstrated a lower level of reparability. The distribution analysis of initial DNA damages after high-dose-rate irradiation revealed a shift towards higher amounts of damage and a broadening in distribution. Thus, increasing the dose rate via changing the pulse frequency of ultrafast electrons leads to an increase in the complexity of DNA damages, with a consequent decrease in their reparability. Since the application of an ultrashort pulsed electron beam permits us to describe the primary radiobiological effects, it can be assumed that the observed dose-rate effect on DNA damage/repair is mainly caused by primary lesions appearing at the moment of irradiation., (© The Author 2017. Published by Oxford University Press on behalf of The Japan Radiation Research Society and Japanese Society for Radiation Oncology.)

Silicones with improved water-driven surface hydrophilicity and anti-biofouling behavior were achieved when bulk-modified with poly(ethylene oxide) (PEO) -silane amphiphiles of varying siloxane tether length: α-(EtO) 3 Si-(CH 2 ) 2 -oligodimethylsiloxane m - block -poly(ethylene oxide) 8 -OCH 3 ( m = 0, 4, 13, 17, 24, and 30). A PEO 8 -silane [α-(EtO) 3 Si-(CH 2 ) 3 -PEO 8 -OCH 3 ] served as a conventional PEO-silane control. To examine anti-biofouling behavior in the absence versus presence of water-driven surface restructuring, the amphiphiles and control were surface-grafted onto silicon wafers and used to bulk-modify a medical-grade silicone, respectively. While the surface-grafted PEO-control exhibited superior protein resistance, it failed to appreciably restructure to the surface-water interface of bulk-modified silicone and thus led to poor protein resistance. In contrast, the PEO-silane amphiphiles, while less protein-resistant when surface-grafted onto silicon wafers, rapidly and substantially restructured in bulk-modified silicone, exhibiting superior hydrophilicity and protein resistance. A reduction of biofilm for several strains of bacteria and a fungus was observed for silicones modified with PEO-silane amphiphiles. Longer siloxane tethers maintained surface restructuring and protein resistance while displaying the added benefit of increased transparency.

Background: Previous studies have demonstrated that surgical patches comprised of small intestinal submucosa-derived extracellular matrix (ECM) have biological remodeling potential. This pilot study investigated histological, mechanical, and bioelectrical properties of an ECM patch implanted in the ovine right-ventricular outflow tract (RVOT)., Materials and Methods: ECM patches (2 × 2 cm 2 ) were implanted in four Western Range sheep (wether males, 37-49 kg, age <1 year) and explanted at 5 months (n = 2) and 8 months (n = 2). In vivo analysis included epicardial echocardiography and contact electrical mapping. Optical mapping was used to map electrical activity of two hearts on a Langendorff preparation. Mechanical testing quantified stiffness. Histological stains characterized structure, neovascularization, and calcification; immunohistochemistry (IHC) assessed cell phenotype., Results: In vivo analysis showed that ECM patch tissue was contractile by M-mode and two-dimensional echocardiographic evaluation. In vivo electrical mapping, and optical mapping confirmed that ECM conducted an organized electrical signal. Mechanical testing of native and ECM patched RVOT tissue showed an elastic modulus of the implanted patch comparable to native tissue stiffness., Conclusions: At 5 and 8 months, the ECM had undergone extracellular matrix remodeling and neovascularization without calcification. The ECM was populated with locally aligned muscle cells positive for sarcomeric alpha-actinin, CD45, and troponin I and T. In sheep, the ECM patch appears to have the potential of remodeling to resemble native, functional ventricular tissue as evidenced by histological, mechanical, and electrical properties. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 1713-1720, 2016., (© 2015 Wiley Periodicals, Inc.)

Poly(ethylene glycol) diacrylate (PEGDA) hydrogels are widely used in biotechnology due to their in situ crosslinking capacity and tunable physical properties. However, as with all single component hydrogels, the modulus of PEGDA networks cannot be tailored independently of mesh size. This interdependence places significant limitations on their use for defined, 3D cell-microenvironment studies and for certain controlled release applications. The incorporation of secondary reactive species (SRS) into PEGDA hydrogels has previously been shown to allow the identification of up to 6 PEGDA hydrogel formulations for which distinct moduli can be obtained at consistent average mesh size (or vice versa). However, the modulus and mesh size ranges which can be probed by these formulations are quite restricted. This work presents an in-depth study of SRS incorporation into PEGDA hydrogels, with the goal of expanding the space for which "decoupled" examination of modulus and mesh size effects is achievable. Towards this end, over 100 PEGDA hydrogels containing either N-vinyl pyrrolidone or star PEG-tetraacrylate as SRS were characterized. To our knowledge, this is the first study to demonstrate that SRS incorporation allows for the identification of a number of modulus ranges that can be probed at consistent average mesh size (or vice versa).

The aortic valve consists of valvular interstitial cells (VICs) and endothelial cells (VECs). While these cells are understood to work synergistically to maintain leaflet structure and valvular function, few co-culture models of these cell types exist. In this study, aortic valve co-cultures (AVCCs) were assembled using magnetic levitation and cultured for 3 days. Immunohistochemistry and quantitative reverse-transcriptase polymerase chain reaction were used to assess the maintenance of cellular phenotype and function, and the formation of extracellular matrix. AVCCs stained positive for CD31 and α-smooth muscle actin (αSMA), demonstrating that the phenotype was maintained. Functional markers endothelial nitric oxide synthase (eNOS), von Willebrand factor (VWF) and prolyl-4-hydroxylase were present. Extracellular matrix components collagen type I, laminin and fibronectin also stained positive, with reduced gene expression of these proteins in three dimensions compared to two dimensions. Genes for collagen type I, lysyl oxidase and αSMA were expressed less in AVCCs than in 2-D cultures, indicating that VICs are quiescent. Co-localization of CD31 and αSMA in the AVCCs suggests that endothelial-mesenchymal transdifferentiation might be occurring. Differences in VWF and eNOS in VECs cultured in two and three dimensions also suggests that the AVCCs possibly have anti-thrombotic potential. Overall, a co-culture model of the aortic valve was designed, and serves as a basis for future experiments to understand heart valve biology., (Copyright © 2013 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

Hydrogel hydrophobicity is an important modulator of mammalian cell behavior, drug payload release, and medical device fouling. Contact angle and protein adsorption measures are two common methods for evaluating hydrogel hydrophobicity. However, protein adsorption is a complex phenomenon which is challenging to interpret in terms of gel hydrophobicity alone. In addition, the permeability of hydrogels can be problematic for contact angle assessment, as this method can only be strictly applied to smooth, solid, and nonpermeable surfaces. Therefore, the development of a technique for measuring hydrogel hydrophobicity which is simple, sensitive, and independent of variations in gel permeability would significantly advance the ability to finely tune this variable. The present technical note develops a method for quantifying the hydrophobicity of hydrogels by exploiting their capacity to swell differentially in solvents of distinct polarities. To validate this technique, hydrogels of varying hydrophobicities were prepared by combining hydrophilic poly(ethylene glycol) diacrylate (PEGDA) with either hydrophobic 3-(trimethoxysilyl) propyl methacrylate (TMSPM) or hydrophilic 2-hydroxyethyl methacrylate (HEMA). The ratio of hydrogel swelling in 70% isopropanol to that in water was termed the hydrophobicity index (H-index) and was determined for each gel type. The measured H-indices reflected known differences in the hydrophobicities of HEMA, TMSPM, and PEGDA and, in contrast to contact angle assessments, appeared to be independent of variations in hydrogel permeability. In addition, the trend in H-indices agreed well with the trend in protein adsorption across hydrogel formulations, although the H-indices appeared to be able to resolve more subtle differences in gel hydrophobicity than protein adsorption measures., (Copyright © 2012 Wiley Periodicals, Inc.)

Experimental results are presented from vacuum-ultraviolet free-electron laser (FEL) operating in the self-amplified spontaneous emission (SASE) mode. The generation of ultrashort radiation pulses became possible due to specific tailoring of the bunch charge distribution. A complete characterization of the linear and nonlinear modes of the SASE FEL operation was performed. At saturation the FEL produces ultrashort pulses (30-100 fs FWHM) with a peak radiation power in the GW level and with full transverse coherence. The wavelength was tuned in the range of 95-105 nm.