Gradient Centrifugation Method Research Articles

Density Gradient Centrifugation Is an Effective Tool to Isolate Cancer Stem-like Cells from Hypoxic and Normoxia Triple-Negative Breast Cancer Models.

Accumulating evidence has indicated that stemness-related genes are associated with the aggressiveness of triple-negative breast cancer (TNBC). Because no universal markers for breast CSCs are available, we applied the density gradient centrifugation method to enrich breast CSCs. We demonstrated that the density centrifugation method allows for the isolation of cancer stem cells (CSCs) from adherent and non-adherent MCF7 (Luminal A), MDA-MB-231 (TNBC) and MDA-MB-468 (TNBC) breast cancer cells. The current study shows that the CSCs' enriched fraction from Luminal A and TNBC cells have an increased capacity to grow anchorage-independently. CSCs from adherent TNBC are mainly characterized by metabolic plasticity, whereas CSCs from Luminal A have an increased mitochondrial capacity. Moreover, we found that non-adherent growth CSCs isolated from large mammospheres have a higher ability to grow anchorage-independently compared to CSCs isolated from small mammospheres. In CSCs, a metabolic shift towards glycolysis was observed due to the hypoxic environment of the large mammosphere. Using a bioinformatic analysis, we indicate that hypoxia HYOU1 gene overexpression is associated with the aggressiveness, metastasis and poor prognosis of TNBC. An in vitro study demonstrated that HYOU1 overexpression increases breast cancer cells' stemness and hyperactivates their metabolic activity. In conclusion, we show that density gradient centrifugation is a non-marker-based approach to isolate metabolically flexible (normoxia) CSCs and glycolytic (hypoxic) CSCs from aggressive TNBC.

Nano-Characterization, Composition Analysis, and Anti-Inflammatory Activity of American-Ginseng-Derived Vesicle-like Nanoparticles.

Medicinal plant-derived vesicle-like nanoparticles can carry chemical components and exert intercellular activity due to the encapsulation of nanostructures. American ginseng is well known as a traditional herb and is commonly used in clinical decoctions. However, the nano-characteristics and chemical composition of American-ginseng-derived vesicle-like nanoparticles (AGVNs) in decoctions are unclear. In this study, the gradient centrifugation method was used to extract and isolate AGVNs. A metabolomic method based on high-resolution mass spectrometry was established to analyze small molecules loaded in AGVNs. Zebrafish and RAW264.7 cells were employed to investigate the anti-inflammatory effects of AGVNs. The results showed that the particle size of AGVNs was generally 243.6 nm, and the zeta potential was -14.5 mV. AGVNs were found to contain 26 ginsenosides (14 protopanaxadiols, 11 protopanaxatriols, and 1 oleanolic acid). Ginsenoside Rb1 and malonyl-ginsenoside Rb1 tended to be enriched in AGVNs. Moreover, AGVNs were found to exert anti-inflammatory effects by reducing macrophage migration in zebrafish and regulating inflammatory factor (NO, TNF-α, IL-6, IL-10) secretion in RAW 264.7 cells. The characterization and analysis of AGVNs provide references and data that support the development of nanoscale anti-inflammatory substances from medicinal plants.

P-176 A novel electrophoretic sperm isolation system achieves equivalent ICSI outcomes to the combined density gradient centrifugation and swim-up method in a significantly shorter processing time

Abstract Study question Does an electrophoretically sperm isolation method, the Felix™ system, have clinical or operational advantages over the combined density gradient centrifugation and swim-up (DGCS) method? Summary answer The Felix™ system produces results that are comparable to the DGCS method, however, Felix™ has the ability to isolate spermatozoa more efficiently. What is known already The isolation of healthy spermatozoa to improve ART outcomes has received enormous attention in the literature recently. Although swim-up and density gradient centrifugation are the most common sperm separation methods, the optimal technique is still unclear. Recently, good sperm selection approaches using various non-centrifugal devices have emerged. Previous reports have shown that a quick and simple sperm separation device, the Felix™ system, can isolate high-quality spermatozoa and improve the results of ART. The Felix™ system combines electrophoresis and separation membranes to collect negatively charged mature normal sperm. Study design, size, duration A prospective oocyte sibling study was conducted between March 2023 and December 2023. The study involved infertile couples (n = 45) with a semen volume of 2.3 mL or more, a motile sperm concentration of 2 million/mL or more, maternal age under 43 years, and at least four mature oocytes at the time of oocyte retrieval. Ejaculated semen was prepared separately using DGCS and Felix™ on the day of oocyte retrieval and subsequent ICSI results were analyzed. Participants/materials, setting, methods In the DGCS group, semen was layered on a 45/90% of sperm grad and centrifuged for 15 minutes, followed by a 30 min swim-up. Subsequently, 0.3 mL of supernatant was collected. In the Felix™ group, 0.3 mL of sperm was collected following six minutes of membrane hydration and electrophoresis. Sperm concentration, total motility, progressive motility and DNA fragmentation (SDFR) were measured. Fertilization, blastocyst development, good-quality blastocyst development, and embryo utilisation rates were also assessed. Main results and the role of chance The average female age at the time of oocyte retrieval was 36.5±4.0 years, and the average male age was 38.1±5.9 years. Of 401 oocytes, 200 and 201 oocytes underwent ICSI using sperm prepared by DGCS and Felix™, respectively. The average processing time of Felix™ was significantly shorter than that of DGCS (54.0±4.3 vs. 7.4±0.2 minutes, p < 0.001, respectively). No significant difference was observed between the DGCS and Felix™ groups for sperm concentration (p = 0.49), motility (p = 0.05), progressive motility (p = 0.34), and SDFR (p = 0.09). Furthermore, there were no significant differences between the two groups with regards to fertilization rate (81.0% vs. 80.6%, p = 0.92), blastocyst development rate (52.9% vs. 58.4%, p = 0.60), good-quality blastocyst development rate (26.1% vs. 35.7%, p = 0.06), and embryo utilisation rate (54.3% vs 58.0%, p = 0.50). Limitations, reasons for caution Although the DGCS method was used as a comparison group, it is necessary to compare the Felix™ system with DGC alone, swim-up alone, or other sperm isolation methods. Larger, more powered studies are required to determine the impact on pregnancy and live birth outcomes. Wider implications of the findings The Felix™ system is a viable option for sperm isolation. While DGCS requires complicated procedures and time-consuming process including centrifugation and incubation; Felix™ requires six minutes only. The Felix™ system reduces processing times significantly and therefore can improve laboratory operations and workflow. Trial registration number Not Applicable

#348 Neutrophil membrane-derived nanovesicles deliver IL-37 to repair renal endothelial cells in ischemia‒reperfusion injury

Abstract Background and Aims Renal ischemia‒reperfusion injury (IRI) is one of the most important causes of acute kidney injury (AKI). Interleukin (IL)-37 is a novel anti-inflammatory factor, but its application is still limited by its low stability and delivery efficiency. In recent years, engineered extracellular vesicles (EVs) have attracted substantial attention as an emerging drug delivery system. The aim of this study was to investigate the reparative effect of neutrophil membranes-derived nanovesicle (N-MV)-delivered IL-37 on renal IRI and its mechanism of action. Method The density gradient centrifugation method was used to extract peripheral blood neutrophils from rats, and the differential centrifugation method was used to extract neutrophil membranes. Cell membranes and IL-37 were then extruded with polycarbonate porous membranes with different pore sizes using a mini extruder to prepare IL-37 that was coated with neutrophil membrane (N-MV@IL-37). Subsequently, the physical and chemical properties and in vitro biological functions were identified. The in vivo distribution of N-MV@IL-37 as well as the renal function and inflammatory response in rats were further evaluated in a rat renal IRI model, and the targeting and anti-inflammatory mechanisms of N-MV@IL-37 were further explored. Results N-MV@IL-37 not only enhanced the stability of IL-37 but also targeted endothelial cells via P-selectin glycoprotein ligand-1 (PSGL-1) on neutrophil membrane surfaces. In vitro experiments showed that N-MV@IL-37 inhibited endothelial cell apoptosis and inflammatory factor production and promoted endothelial cell viability and angiogenesis. In the rat renal IRI model, N-MV@IL-37 inhibited renal cell apoptosis and alleviated inflammatory responses, thereby improving renal function in IRI rats. Conclusion N-MVs provide an effective method of delivering IL-37, thereby alleviating the inflammatory response due to renal IRI and repairing renal endothelial cells; these vesicles could be a potential system for the treatment of renal IRI. Meanwhile, N-MVs also provided a drug delivery platform to provide a new strategy for the treatment of other IRI-like diseases.

Characterization of Sex-Dependent Differences in Brain Microvascular Bioenergetics

Background: Women experience increased incidence of stroke-related deaths and lifetime risk of Alzheimer's disease (AD). Microvascular dysfunction has been implicated in the pathogenesis of ischemic stroke and AD. Our objective is to investigate the sex-dependent differences in bioenergetics of young mouse brain microvessels (BMVs). Methods: BMVs were isolated from young male and female mice (3-4 months), using a combination of gradient centrifugation and filtration (300μm and 40μm filters) methods. Extracellular acidification rate (ECAR) and oxygen consumption rate (OCR) of BMVs were measured utilizing the Agilent Seahorse XFe 24 analyzer. The levels of proteins and mRNAs of mitochondrial respiratory complexes were measured by western blot and RT-PCR, respectively. Citrate synthase (CS) enzyme activity and ATP levels were determined in lysates of BMVs. Results: Real-Time ATP Rate assay demonstrated a decreased total ATP production rate and ATP contribution from both glycolysis and oxidative phosphorylation (OxPhos) in BMVs from females compared to males. Mitochondrial stress test assay revealed significantly lower values of several mitochondrial respiratory parameters, including basal respiration, ATP production, maximal respiration, spare respiratory capacity, and proton leak in BMVs from females compared to males. Glycolytic Rate assay uncovered reduced basal glycolysis, proton efflux rate (PER) originating from basal glycolysis, and the mitoOCR/glycoPER ratio in BMVs from females compared to males. Interestingly, no sex-dependent differences were observed in basal PER and post-2-DG acidification rates in BMVs. Mito Fuel Flex Test assay showed no sex-dependent difference in the utilization of glucose, glutamine, and long-chain fatty acids as fuel substrates in BMVs. ATP measurements confirmed the reduced ATP levels in BMVs from females compared to males. Measurements of CS activity revealed no sex-dependent difference in the BMVs. Lastly, Western blot and RT-PCR experiments indicated no differences in either protein or mRNA levels of various mitochondrial complex protein levels.Conclusions: Female BMVs showed reduced mitochondrial respiratory and glycolytic parameters compared to male BMVs although relative contribution of various substrates for energy production were not different. These sex-dependent differences involving glycolysis and OxPhos make the microvasculature vulnerable to injury in females. Funding sources: NIH grants AG074489 and NS114286 (PVGK and RM). This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

A Comparative Study of B Cell Blast Isolation Methods from Bone Marrow Aspirates of Pediatric Leukemia Patients.

Density gradient centrifugation is a conventional technique widely utilized to isolate bone marrow mononuclear cells (BM-MNC) from bone marrow (BM) aspirates obtained from pediatric B-cell acute lymphoblastic leukemia (B-ALL) patients. Nevertheless, this technique achieves incomplete recovery of mononuclear cells and is relatively time-consuming and expensive. Given that B-ALL is the most common childhood malignancy, alternative methods for processing B-ALL samples may be more cost-effective. In this pilot study, we use several readouts, including immune phenotype, cell viability, and leukemia-initiating capacity in immune-deficient mice, to directly compare the density gradient centrifugation and buffy coat processing methods. Our findings indicate that buffy coat isolation yields comparable BM-MNC product in terms of both immune and leukemia cell content and could provide a viable, lower cost alternative for biobanks processing pediatric leukemia samples.

Methods to Isolate Muscle Stem Cells for Cell-Based Cultured Meat Production: A Review.

Cultured meat production relies on various cell types, including muscle stem cells (MuSCs), embryonic stem cell lines, induced pluripotent cell lines, and naturally immortalized cell lines. MuSCs possess superior muscle differentiation capabilities compared to the other three cell lines, making them key for cultured meat development. Therefore, to produce cultured meat using MuSCs, they must first be effectively separated from muscles. At present, the methods used to isolate MuSCs from muscles include (1) the pre-plating method, using the ability of cells to adhere differently, which is a biological characteristic of MuSCs; (2) the density gradient centrifugation method, using the intrinsic density difference of cells, which is a physical characteristic of MuSCs; and (3) fluorescence- and magnetic-activated cell sorting methods, using the surface marker protein on the cell surface of MuSCs, which is a molecular characteristic of MuSCs. Further efficient and valuable methods for separating MuSCs are expected to be required as the cell-based cultured meat industry develops. Thus, we take a closer look at the four methods currently in use and discuss future development directions in this review.

MSC-Derived Exosomes Mitigate Myocardial Ischemia/Reperfusion Injury by Reducing Neutrophil Infiltration and the Formation of Neutrophil Extracellular Traps.

Acute inflammatory storm is a major cause of myocardial ischemia/reperfusion (I/R) injury, with no effective treatment currently available. The excessive aggregation of neutrophils is correlated with an unfavorable prognosis in acute myocardial infarction (AMI) patients. Exosomes derived from mesenchymal stromal cells (MSC-Exo) have certain immunomodulatory potential and might be a therapeutic application. Therefore, we investigated the protective role of MSC-Exo in modulating neutrophil infiltration and formation of neutrophil extracellular traps (NETs) following myocardial I/R injury. Exosomes were isolated from the supernatant of MSCs using a gradient centrifugation method. We used flow cytometry, histochemistry, and immunofluorescence to detect the changes of neutrophils post-intravenous MSC-Exo injection. Additionally, cardiac magnetic resonance (CMR) and thioflavin S experiments were applied to detect microvascular obstruction (MVO). The NLR family pyrin domain containing 3 (NLRP3) inflammasome was examined for mechanism exploration. Primary neutrophils were extracted for in vitro experiment. Antibody of Ly6G was given to depleting the neutrophils in mice for verification the effect of MSC-Exo. Finally, we analyzed the MiRNA sequence of MSC-Exo and verified it in vitro. MSC-Exo administration reduced neutrophil infiltration and NETs formation after myocardial I/R. MSC-Exo treatment also could attenuate the activation of NLRP3 inflammasome both in vivo and in vitro. At the same time, the infarction size and MVO following I/R injury were reduced by MSC-Exo. Moreover, systemic depletion of neutrophils partly negated the therapeutic effects of MSC-Exo. Up-regulation of miR-199 in neutrophils has been shown to decrease the expression of NETs formation after stimulation. Our results demonstrated that MSC-Exo mitigated myocardial I/R injury in mice by modulating neutrophil infiltration and NETs formation. This study provides novel insights into the potential therapeutic application of MSC-Exo for myocardial ischemia/reperfusion injury.

Swim-up method is superior to density gradient centrifugation for preserving sperm DNA integrity during sperm processing.

This study aimed to evaluate the effects of swim-up and density gradient centrifugation methods on sperm DNA fragmentation. Nineteen normozoospermic patient samples with ≥100 × 106 motile sperms were included in this study. Sperm DNA fragmentation, progressive motility, and progressive motile sperm number were measured before and after the swim-up method or density gradient centrifugation. Sperm DNA fragmentation was not statistically different between swim-up-(14.4 ± 2.1%, p = 0.32) and density gradient centrifugation-processed (25.0 ± 3.0%, p = 0.20) and unprocessed semen samples (19.2 ± 1.9%). Sperm DNA fragmentation was significantly lower in swim-up-than in density gradient centrifugation-processed samples (p < 0.05). Sperm progressive motility was significantly higher (p < 0.05) in swim-up-(92.9 ± 1.0%) and density gradient centrifugation-processed (81.3 ± 2.0%) samples, with the former being higher, than in unprocessed semen samples (53.1 ± 3.7%). The recovery rate of progressive motile sperms was significantly lower in swim-up-(9.7 ± 1.4%) than in density gradient centrifugation-processed samples (17.2 ± 1.8%, p < 0.05). The swim-up method is superior to density gradient centrifugation, evidenced by less sperm DNA fragmentation and higher sperm progressive motility. The recovery rate of progressive motile sperms was better after density gradient centrifugation than after swim-up.

A Novel, Efficient Method to Isolate Chicken Primordial Germ Cells from Embryonic Blood Using Cell Culture Inserts.

Primordial germ cells (PGCs) play a crucial role in preserving poultry genetic resources and conducting transgenic research. A system for the rapid isolation of PGCs from single chicken embryonic blood was established in this paper. We found that PGCs can migrate to the lower layer of chicken embryonic fibroblasts (CEFs) through pores smaller than their diameter, while blood cells cannot, when co-cultured with CEFs of passages two to three. Based on the characteristics of PGCs, we developed a new PGC isolation method (cell culture insert/CEF adhesion method) that utilizes a 3 μm cell culture insert and CEFs of passages two to three. Using this method, approximately 700 PGCs can be isolated from the blood of a single chicken embryo at Hamburger and Hamilton (H&H) stage 17 of development. The separation rate achieved was 87.5%, with a separation purity of 95%. The separation rate of this method was 41.4% higher than the common Percoll density gradient centrifugation method and 33.6% higher than lysis with ACK buffer. PGCs isolated from embryonic blood could proliferate 37-fold within 2 weeks when cultured in a feeder-free culture system. They also continued to express the SSEA-1 and DAZL proteins and retained the ability to migrate in vivo. Overall, PGCs separated using cell culture inserts/CEF adhesion method retain their stem cell characteristics and migration ability. PGCs also exhibit good proliferation efficiency, making them suitable for subsequent transgenic experiments or genetic resource preservation.

Aldehyde Dehydrogenase Enzyme in Relation to Cord Blood stem cells Potency

Abstract Introduction/Objective In umbilical cord blood transplantation (UCBT), the number of cluster of differentiation (CD)34+ cells and colony-forming units (CFUs) in the cord blood (CB) graft positively correlate with patient survival. Since aldehyde dehydrogenase (ALDH) activity is high in hematopoietic stem cells, the number of ALDH-bright (ALDHbr) cells was examined in comparison with the number of CD34+ cells and CFUs for the quality assessment of CB units, Aim and objectives; to correlate the aldehyde dehydrogenase (ALDH) enzyme assay with colony-forming unit–granulocyte/macrophage (CFU-GM) assay before cryopreservation of cord blood buffy coats (CBBC), in order to investigate the hypothesis that the ALDH assay might exclude apoptotic cells since it is based on enzyme activity. Methods/Case Report This study was carried out at Benha University Hospital on Fifty (50) samples of Human Umbilical Cord Blood which were processed for mononuclear cells (MNC) separation by density gradient centrifugation method using Ficoll-Paque media that layered on the diluted blood. In parallel, 1 million nucleated cells were sampled and prepared for flow cytometry for analysis of ALDH activity according to the manufacturer’s instructions. Results (if a Case Study enter NA) CD34+ ALDH+ (%) (Of MNC) showed significant positive correlation with ALDH++ (%) (Of CD34+) and numbers of total CFU/40000 cells. Also ALDH++ (%) (Of CD34+) showed significant positive correlation with numbers of total CFU/40000 cells. Conclusion The ALDH assay excludes nonviable and apoptotic cells, and therefore correlates well with CFU enumeration compared to the number of viable CD34+ cells. We propose that the ALDH assay might replace the CFU-GM method in CBU potency measurements.

The efficacy of various protocols of colloidal centrifugation of bovine sperm for IVF

The article presents data on the effectiveness of using various sperm preparation protocols by colloidal centrifugation (density gradient centrifugation method) before procedures of assisted reproductive technologies, including in vitro artificial insemination. The use of the method can affect the quality of sexual gametes and the viability of embryos, increase the percentage of successful embryotransplantation and contribute to the appearance of highly productive offspring.As a result of the research, the most optimal protocol of centrifugation by the method of gradient layering with indicators of the first and second centrifugation 700g – 20 min and 100g – 10 min, respectively, was determined by morphofunctional characteristics. The average rate of motile spermatozoa was 84.1±5.1%, progressive spermatozoa – 68.7±5.1%, the rate of rectilinear translational motion was 49.69 microns/sec. Morphology and viability meet quality standards.

Percoll discontinuous density gradient centrifugation method for the fractionation of the subpopulations of Mycobacterium smegmatis and Mycobacterium tuberculosis from in vitro cultures

Bacterial populations in the in vitro laboratory cultures, environment, and patients contain metabolically different subpopulations that respond differently to stress agents, including antibiotics, and emerge as stress tolerant or resistant strains. To contain the emergence of such strains, it is important to study the features of the metabolic status and response of the subpopulations to stress agents. For this purpose, an efficient method is required for the fractionation and isolation of the subpopulations from the cultures. Here we describe in detail the manual setting up of a simple, easy-to-do, reproducibly robust Percoll discontinuous density gradient centrifugation for the fractionation of subpopulations of short-sized cells (SCs) and normal/long-sized cells (NCs) from Mycobacterium smegmatis and Mycobacterium tuberculosis cultures, which we had reported earlier. About 90-98% enrichment was obtained respectively for SCs and NCs for M. smegmatis and 69-67% enrichment was obtained respectively for the SCs and NCs for M. tuberculosis.•The Percoll discontinuous density gradient centrifugation helps the fractionation and isolation of mycobacterial subpopulations that differ in density.•The method offers a consistently reproducible high enrichment of the subpopulations of SCs and NCs from the in vitro cultures of M. smegmatis and M. tuberculosis.•Our earlier reports on the consistency in the differential response of the subpopulations, enriched using the method, to oxidative, nitrite, and antibiotic stress proves its validity.

Time- and Concentration-Dependent Adverse Effects of Paclitaxel on Non-Neuronal Cells in Rat Primary Dorsal Root Ganglia.

Paclitaxel is a chemotherapeutic agent used to treat a wide range of malignant tumors. Although it has anti-tumoral properties, paclitaxel also shows significant adverse effects on the peripheral nervous system, causing peripheral neuropathy. Paclitaxel has previously been shown to exert direct neurotoxic effects on primary DRG neurons. However, little is known about paclitaxel's effects on non-neuronal DRG cells. They provide mechanical and metabolic support and influence neuronal signaling. In the present study, paclitaxel effects on primary DRG non-neuronal cells were analyzed and their concentration or/and time dependence investigated. DRGs of Wister rats (6-8 weeks old) were isolated, and non-neuronal cell populations were separated by the density gradient centrifugation method. Different concentrations of Paclitaxel (0.01 µM-10 µM) were tested on cell viability by MTT assay, cell death by lactate dehydrogenase (LDH) assay, and propidium iodide (PI) assay, as well as cell proliferation by Bromodeoxyuridine (BrdU) assay at 24 h, 48 h, and 72 h post-treatment. Furthermore, phenotypic effects have been investigated by using immunofluorescence techniques. Paclitaxel exhibited several toxicological effects on non-neuronal cells, including a reduction in cell viability, an increase in cell death, and an inhibition of cell proliferation. These effects were concentration- and time-dependent. Cellular and nuclear changes such as shrinkage, swelling of cell bodies, nuclear condensation, chromatin fragmentation, retraction, and a loss in processes were observed. Paclitaxel showed adverse effects on primary DRG non-neuronal cells, which might have adverse functional consequences on sensory neurons of the DRG, asking for consideration in the management of peripheral neuropathy.

Small Extracellular Vesicles from Periodontal Ligament Stem Cells Primed by Lipopolysaccharide Regulate Macrophage M1 Polarization via miR-433-3p Targeting TLR2/TLR4/NF-κB

—Lipopolysaccharide (LPS) is regarded as the main pathogenic factor of periodontitis. Mesenchymal stem cell–derived small extracellular vesicles (sEVs) play a key role in a variety of physiological and pathological processes. This study investigated the effects of sEVs derived from periodontal ligament stem cells (PDLSCs) pretreated with LPS on macrophage polarization and the underlying mechanisms. PDLSCs were treated with LPS (1 µg/mL) for 24 h, and sEVs were harvested by gradient centrifugation method. Macrophages were incubated with sEVs for 24 h, followed by examination of the expression profiles of inflammatory and anti-inflammatory cytokines, and polarization markers. Furthermore, microarray analysis, western blot test, and microRNA inhibitor transfection experiments were used to elucidate the molecular signaling pathway responsible for the process. The results showed that sEVs derived from LPS-preconditioning PDLSCs could significantly increase the expression of M1 markers and inflammatory cytokines, whereas decreased the expression of M2 markers and anti-inflammatory cytokines. Mechanistic analysis showed that TLR2/TLR4/NF-κB p65 pathway was involved in M1 polarization of macrophages, and microRNA-433-3p played a role, at least in part, in the course. Collectively, LPS could promote the macrophages into M1 status via TLR2/TLR4/NF-κB p65 signaling pathway partly by sEV-mediated microRNA-433-3p, which could be a potential therapeutic target for periodontitis.

P-782 The influence of microfluidic preparation of spermatozoa for ICSI (intracytoplasmic sperm injection) in an unselected IVF population on fertilization rate, embryo-quality and pregnancy rate

Abstract Study question Does the microfluidic technique as a new preparation option for sperm in ICSI during IVF have a better outcome in fertilization, blastocysts and pregnancy rate? Summary answer The patients that had the sperm preparation for ICSI with the microfluidic sperm selection had similar results as with the gradient centrifugation selection. What is known already Semen analysis is a poor predictor of the fertilization potential of spermatozoa and a male factor may contribute to poor outcomes of IVF procedure despite a normal semen analysis. Traditionally, sperm processing is accomplished by density gradient centrifugation or swim-up methods but this have been shown in some studies to increase reactive oxygen species and induce sperm DNA fragmentation. The microfluidic sperm selection (ZyMot- ICSI) is based on the selection of the spermatozoa with the lowest DNA fragmentation rate but studies do not prove better clinical outcomes after this method. Study design, size, duration This is a prospective randomized study carried out in a university level fertility clinic in Oradea, Romania from January 2022 to December 2022, including 239 patients in total. The patients that underwent IVF-ICSI procedures for various indications were randomized in two groups: the control group swim-up technique was used for sperm selection for ICSI during IVF and the study group with the ZyMot-ICSI (microfluidic sperm selection technique) was used. Participants/materials, setting, methods We conducted a prospective trial comparing 119 couples that were allocated to the classic swim-up technique (control group) and 120 couples that were allocated with the microfluidic technique was used (study group) in our university level clinic to go through IVF. Inclusion criteria were couples with known infertility requiring IVF and willing to participate in the study. Exclusion criteria were: severe oligoasthenospermia (concentration &amp;lt; 5x10^6 spermatozoa/ml or motility &amp;lt;10%), oocyte or sperm donation. Main results and the role of chance The statistical analysis showed that there is no significant difference between the fertilization rate (study vs control p = 0.37 with absolute difference -1.182, 95% CI (-7.2, 5.4)) or blastocyst rate (study vs control p = 0.88 with absolute difference -0.5 95% (-6.5, 6)) nor is there a difference in clinical pregnancy. Even if microfluidic preparation of spermatozoa did not seem to improve the results it may be utilized more broadly for standard IVF, intrauterine insemination and could also improve workflow, decrease intervention by laboratory personal and provide more consistent incubation conditions. Limitations, reasons for caution The population studied was inclusive with unselected IVF indications and did not attempt to isolate male factor infertility cases or patients with a history of elevated sperm DNA fragmentation. Wider implications of the findings Microfluidic sperm preparation performs similarly to density gradient centrifugation in sperm preparation for IVF in an unselected population. Trial registration number Not applicable

FOF1-ATPase Motor-Embedded Chromatophore as Drug Delivery System: Extraction, Cargo Loading Ability and Mucus Penetration Ability.

Mucosal drug delivery permits direct and prompt drug absorption, which is capable of reducing undesirable decomposition that occurs before absorption. However, mucus clearance of those mucosal drug delivery systems strongly retards their actual application. Herein, we propose chromatophore nanoparticles embedded with FOF1-ATPase motors to promote mucus penetration. The FOF1-ATPase motor-embedded chromatophores were firstly extracted from Thermus thermophilus by using a gradient centrifugation method. Then, the model drug (curcumin) was loaded onto the chromatophores. The drug loading efficiency and entrapment efficiency were optimized by using different loading approaches. The activity, motility, stability and mucus permeation of the drug-loaded chromatophore nanoparticles were thoroughly investigated. Both the in vitro and in vivo studies revealed that the FOF1-ATPase motor-embedded chromatophore successfully enhanced mucus penetration glioma therapy. This study indicates that the FOF1-ATPase motor-embedded chromatophore is a promising alternative as a mucosal drug delivery system.

Efficiency of Density Gradient Centrifugation Method (Ludox method) Based on eDNA for the Analysis of Harmful Algal Bloom Potential

Efficiency of Density Gradient Centrifugation Method (Ludox method) Based on eDNA for the Analysis of Harmful Algal Bloom Potential

Comparison between density gradient centrifugation method, an extended version of the horizontal swim up method and the combination of both for sperm selection.

To compare the degree of efficiency between density gradient centrifugation (DGC) method and an extended horizontal swim-up (SU) method. A total of 97 couples undergoing in vitro fertilization were enrolled in the study. Semen samples were divided into three aliquots and treated using DGC, extended horizontal SU, and combined methods. DNA fragmentation and chromatin decondensation were detected in native semen samples and their three corresponding aliquots. The corresponding mature oocytes of each semen sample were divided into two sibling cultures. The first sibling culture was microinjected with semen pellets from DGC, and the second sibling culture was microinjected with semen pellets from the combination of both methods. Fertilization rate and embryonic development were assessed at day 3. DNA fragmentation and chromatin decondensation was significantly low in DGC and extended horizontal SU samples; however, the rates of DNA fragmentation and chromatin decondensation were significantly lower in extended horizontal SU samples than in DGC samples. The lowest rates of DNA fragmentation and chromatin decondensation corresponded to the samples treated with both methods. The highest rates of DNA fragmentation and chromatin decondensation corresponded to the samples treated with DGC. No significant difference was found in the fertilization rate or day 3 embryos between sibling cultures. The combination of DGC and the extended horizontal SU techniques is best for giving the lowest rates of sperm DNA fragmentation and chromatin decondensation.

A simple gradient centrifugation method for bacteria detection in skim milk

Development of simple methods for bacteria detection is of great importance, especially in the undeveloped countries where there are limited resources for microbial testing. Herein, we present a simple gradient centrifugation-based optical detection (GCB-OD) method for bacteria testing in skim milk. Our method incorporates capturing bacteria using nanoparticles in Eppendorf tubes, followed by separation of bacteria-captured particles in the sucrose gradient within 6 min of centrifugation. Using a simple mobile phone-setup, images of sucrose-gradients are captured, and optical density of the particle-bound bacteria zones are measured with a MATLAB software, without requirement of a sophisticated optical instrument. In this approach, different nanoparticles are compared according to delta-E (ΔE) color difference value and sedimentation rate to obtain detectable narrow particle-bound bacteria zones. The spherical shaped carbon nanoparticles (CNP) with mean diameters of 119 nm, are found suitable for low concentrations of bacteria detection for having high sedimentation rates comparing to smaller sized particles and having higher ΔE than other particles as well. For CNP-captured bacteria band detection, sucrose-gradient consist of 1 ml of 60–65–70 % (w/v) and 2 ml of 75 % (w/v) sucrose was found suitable.Escherichia coli(E. coli) was used as model fecal indicator bacteria, and the correlation of optical density andE. coliconcentration showed linearity in the range of 1.5x100–1.5x104CFU/mlE. coliin skim milk. The culture plating and transmission electron micrographs were utilized to evaluate bacterial capture performance. The developed simple centrifugation-based method that allows detection of 2 CFU/ml and 3 CFU/ml E. coliin 1XPBS and skim milk, can be useful for microbial testing in resource limited areas.