Shear Stress and the AMP-Activated Protein Kinase Independently Protect the Vascular Endothelium from Palmitate Lipotoxicity.

Saturated free fatty acids are thought to play a critical role in metabolic disorders associated with obesity, insulin resistance, type 2 diabetes (T2D), and their vascular complications via effects on the vascular endothelium. The most abundant saturated free fatty acid, palmitate, exerts lipotoxic effects on the vascular endothelium, eventually leading to cell death. Shear stress activates the endothelial AMP-activated protein kinase (AMPK), a cellular energy sensor, and protects endothelial cells from lipotoxicity, however their relationship is uncertain. Here, we used isoform-specific shRNA-mediated silencing of AMPK to explore its involvement in the long-term protection of macrovascular human umbilical vein endothelial cells (HUVECs) against palmitate lipotoxicity and to relate it to the effects of shear stress. We demonstrated that it is the α1 catalytic subunit of AMPK that is critical for HUVEC protection under static conditions, whereas AMPK-α2 autocompensated a substantial loss of AMPK-α1, but failed to protect the cells from palmitate. Shear stress equally protected the wild type HUVECs and those lacking either α1, or α2, or both AMPK-α isoforms; however, the protective effect of AMPK reappeared after returning to static conditions. Moreover, in human adipose microvascular endothelial cells isolated from obese diabetic individuals, shear stress was a strong protector from palmitate lipotoxicity, thus highlighting the importance of circulation that is often obstructed in obesity/T2D. Altogether, these results indicate that AMPK is important for vascular endothelial cell protection against lipotoxicity in the static environment, however it may be dispensable for persistent and more effective protection exerted by shear stress.

Determination of the Allelic Composition of the sdw1/denso (HvGA20ox2), uzu1 (HvBRI1) and ari-e (HvDep1) Genes in Spring Barley Accessions from the VIR Collection.

The lodging of barley significantly limits its potential yield, leads to the deterioration of grain quality, and complicates mechanized harvesting. More than 30 dwarfness and semi-dwarfness genes and loci are known for barley, and their involvement in breeding can solve the problem of lodging. The most common dwarfing alleles are of the genes sdw1/denso (HvGA20ox2), uzu1 (HvBRI1), and ari-e (HvDep1). The aim of this study was the design of dCAPS markers for the sdw1.c and ari-e.GP alleles and the molecular screening of barley accessions from the VIR collection for identifying these and other dwarfing alleles commonly used in breeding. Two dCAPS markers have been developed to identify the sdw1.c allele of the HvGA20ox2 gene and ari-e.GP of HvDep1. These dCAPS markers and two known from the literature CAPS and dCAPS markers of the alleles sdw1.a/sdw1.e, sdw1.c, sdw1.d, and uzu1.a were used in the molecular screening of 32 height-contrasting barley accessions. This made it possible to identify the accessions with alleles sdw1.a/sdw1.e, sdw1.c, and sdw1.d of the HvGA20ox2 gene, as well as accessions with a combination of sdw1.c and uzu1.a alleles of the genes HvGA20ox2 and HvBRI1. A comparison of the results of genotyping and phenotyping showed that the presence of dwarfing alleles in all genotypes determines high or medium lodging resistance regardless of the influence of weather conditions. Twelve accessions were found to contain the new allele sdw1.ins of the HvGA20ox2 gene, which differs from the known allele sdw1.c by a larger size of PCR products. It is characterized by the Thalos_2 transposon insertion; the subsequent GTTA insertion, common with the sdw1.c allele; and by a single-nucleotide G→A substitution at the 165 position.

Magnetic Resonance-Based Analytical Tools to Study Polyvinylpyrrolidone-Hydroxyapatite Composites.

The synthesis of biocompatible and bioresorbable composite materials, such as a "polymer matrix-mineral constituent," stimulating the natural growth of living tissues and the restoration of damaged parts of the body, is one of the challenging problems in regenerative medicine and materials science. Composite films of bioresorbable polymer of polyvinylpyrrolidone (PVP) and hydroxyapatite (HA) were obtained. HA was synthesized in situ in the polymer solution. We applied electron paramagnetic resonance (EPR) and nuclear magnetic resonance (NMR) approaches to study the composite films' properties. The application of EPR in two frequency ranges allowed us to derive spectroscopic parameters of the nitrogen-based light and radiation-induced paramagnetic centers in HA, PVP and PVP-HA with high accuracy. It was shown that PVP did not significantly affect the EPR spectral and relaxation parameters of the radiation-induced paramagnetic centers in HA, while light-induced centers were detected only in PVP. Magic angle spinning (MAS) 1H NMR showed the presence of two signals at 4.7 ppm and -2.15 ppm, attributed to "free" water and hydroxyl groups, while the single line was attributed to 31P. NMR relaxation measurements for 1H and 31P showed that the relaxation decays were multicomponent processes that can be described by three components of the transverse relaxation times. The obtained results demonstrated that the applied magnetic resonance methods can be used for the quality control of PVP-HA composites and, potentially, for the development of analytical tools to follow the processes of sample treatment, resorption, and degradation.

Evaluation of the Polygenic Risk Score for Alzheimer's Disease in Russian Patients with Dementia Using a Low-Density Hydrogel Oligonucleotide Microarray.

The polygenic risk score (PRS), together with the ɛ4 allele of the APOE gene (APOE-ɛ4), has shown high potential for Alzheimer's disease (AD) risk prediction. The aim of this study was to validate the model of polygenic risk in Russian patients with dementia. A microarray-based assay was developed to identify 21 markers of polygenic risk and ɛ alleles of the APOE gene. This case-control study included 348 dementia patients and 519 cognitively normal volunteers. Cerebrospinal fluid (CSF) amyloid-ß (Aß) and tau protein levels were assessed in 57 dementia patients. PRS and APOE-ɛ4 were significant genetic risk factors for dementia. Adjusted for APOE-ɛ4, individuals with PRS corresponding to the fourth quartile had an increased risk of dementia compared to the first quartile (OR 1.85; p-value 0.002). The area under the curve (AUC) was 0.559 for the PRS model only, and the inclusion of APOE-ɛ4 improved the AUC to 0.604. PRS was positively correlated with tTau and pTau181 and inversely correlated with Aß42/Aß40 ratio. Carriers of APOE-ɛ4 had higher levels of tTau and pTau181 and lower levels of Aß42 and Aß42/Aß40. The developed assay can be part of a strategy for assessing individuals for AD risk, with the purpose of assisting primary preventive interventions.

Long-Term Experimental Hyperglycemia Does Not Impair Macrovascular Endothelial Barrier Integrity and Function in vitro.

Hyperglycemia is a hallmark of type 2 diabetes implicated in vascular endothelial dysfunction and cardiovascular complications. Many in vitro studies identified endothelial apoptosis as an early outcome of experimentally modeled hyperglycemia emphasizing cell demise as a significant factor of vascular injury. However, endothelial apoptosis has not been observed in vivo until the late stages of type 2 diabetes. Here, we studied the long-term (up to 4 weeks) effects of high glucose (HG, 30 mM) on human umbilical vein endothelial cells (HUVEC) in vitro. HG did not alter HUVEC monolayer morphology, ROS levels, NO production, and exerted minor effects on the HUVEC apoptosis markers. The barrier responses to various clues were indistinguishable from those by cells cultured in physiological glucose (5 mM). Tackling the key regulators of cytoskeletal contractility and endothelial barrier revealed no differences in the histamine-induced intracellular Ca2+ responses, nor in phosphorylation of myosin regulatory light chain or myosin light chain phosphatase. Altogether, these findings suggest that vascular endothelial cells may well tolerate HG for relatively long exposures and warrant further studies to explore mechanisms involved in vascular damage in advanced type 2 diabetes.

Polyvinylpyrrolidone-Alginate Film Barriers for Abdominal Surgery: Anti-Adhesion Effect in Murine Model.

Surgical operations on the peritoneum are often associated with the formation of adhesions, which can interfere with the normal functioning of the internal organs. The effectiveness of existing barrier materials is relatively low. In this work, the effectiveness of soluble alginate-polyvinylpyrrolidone (PVP-Alg) and non-soluble Ca ion cross-linked (PVP-Alg-Ca) films in preventing these adhesions was evaluated. Experiments in vivo were performed on mice via mechanical injury to the adjacent peritoneum wall and the caecum, followed by the application of PVP-Alg or PVP-Alg-Ca films to the injured area. After 7 days, samples from the peritoneal wall and caecum were analyzed using histology and quantitative polymerase chain reaction (qPCR). It was shown that the expression of genes responsible for adhesion formation in the caecum in the PVP-Alg group was comparable to that in the control group, while in the PVP-Alg-Ca group, it increased by 5-10 times. These results were consistent with the histology: in the PVP-Alg group, the adhesions did not form, while in the PVP-Alg-Ca group, the adhesions corresponded to five points on the adhesion scale. Therefore, the formation of intraperitoneal adhesions can be effectively prevented by non-crosslinked, biodegradable PVP-Alg films, whereas cross-linked, not biodegradable PVP-Alg-Ca films cause inflammation and adhesion formation.

Effects of Antiplatelet Drugs on Platelet-Dependent Coagulation Reactions.

Activated platelets are involved in blood coagulation by exposing phosphatidylserine (PS), which serves as a substrate for assembling coagulation complexes. Platelets accelerate fibrin formation and thrombin generation, two final reactions of the coagulation cascade. We investigated the effects of antiplatelet drugs on platelet impact in these reactions and platelet ability to expose PS. Washed human platelets were incubated with acetylsalicylic acid (ASA), ticagrelor, ASA in combination with ticagrelor, ruciromab (glycoprotein IIb-IIIa antagonist), or prostaglandin E1 (PGE1). Platelets were not activated or activated by collagen and sedimented in multiwell plates, and plasma was added after supernatant removal. Fibrin formation (clotting) was monitored in a recalcification assay by light absorbance and thrombin generation in a fluorogenic test. PS exposure was assessed by annexin V staining using flow cytometry. Ticagrelor (alone and in combination with ASA), ruciromab, and PGE1, but not ASA, prolonged the lag phase and decreased the maximum rate of plasma clotting and decreased the peak and maximum rate of thrombin generation. Inhibition was observed when platelets were not treated with exogenous agonists (activation by endogenous thrombin) and pretreated with collagen. Ticagrelor (alone and in combination with ASA), ruciromab, and PGE1, but not ASA, decreased PS exposure on washed platelets activated by thrombin and by thrombin + collagen. PS exposure on activated platelets in whole blood was lower in patients with acute coronary syndrome receiving ticagrelor + ASA in comparison with donors free of medications. These results indicate that antiplatelet drugs are able to suppress platelet coagulation activity not only in vitro but also after administration to patients.

Zn-Doped Calcium Magnesium Phosphate Bone Cement Based on Struvite and Its Antibacterial Properties.

The development of magnesium calcium phosphate bone cements (MCPCs) has garnered substantial attention. MCPCs are bioactive and biodegradable and have appropriate mechanical and antimicrobial properties for use in reconstructive surgery. In this study, the cement powders based on a (Ca + Mg)/P = 2 system doped with Zn2+ at 0.5 and 1.0 wt.% were obtained and investigated. After mixing with a cement liquid, the structural and phase composition, morphology, chemical structure, setting time, compressive strength, degradation behavior, solubility, antibacterial activities, and in vitro behavior of the cement materials were examined. A high compressive strength of 48 ± 5 MPa (mean ± SD) was achieved for the cement made from Zn2+ 1.0 wt.%-substituted powders. Zn2+ introduction led to antibacterial activity against Staphylococcus aureus and Escherichia coli strains, with an inhibition zone diameter of up to 8 mm. Biological assays confirmed that the developed cement is cytocompatible and promising as a potential bone substitute in reconstructive surgery.

InDel and SCoT Markers for Genetic Diversity Analysis in a Citrus Collection from the Western Caucasus.

Citrus collections from extreme growing regions can be an important source of tolerant germplasms for the breeding of cold-tolerant varieties. However, the efficient utilization of these germplasms requires their genetic background information. Thus, efficient marker systems are necessary for the characterization and identification of valuable accessions. In this study, the efficiency of 36 SCoT markers and 60 InDel markers were evaluated as part of the broad citrus collection of the Western Caucasus. The interspecific and intraspecific genetic diversity and genetic structures were analyzed for 172 accessions, including 31 species and sets of the locally derived cultivars. Single markers, such as SCoT18 (0.84), SCoT20 (0.93), SCoT23 (0.87), SCoT31 (0.88), SCoT36 (0.87) и LG 1-4 (0.94), LG 4-3 (0.86), LG 7-11 (0.98), and LG 8-10 (0.83), showed a high discriminating power, indicating the good applicability of these markers to assess intraspecific diversity of the genus Citrus. Overall, SCoT markers showed a higher level of polymorphism than InDel markers. According to analysis of population structure, SCoT and InDel markers showed K = 9 and K = 5 genetic clusters, respectively. The lowest levels of genetic admixtures and diversity were observed among the locally derived satsumas and lemons. The highest level of genetic admixtures was observed in the lime group. Phylogenetic relationships indicated a high level of interspecific genetic diversity but a low level of intraspecific diversity in locally derived satsumas and lemons. The results provide new insight into the origin of citrus germplasms and their distribution in colder regions. Furthermore, they are important for implementing conservation measures, controlling genetic erosion, developing breeding strategies, and improving breeding efficiency.

Effects of Various Ripening Media on the Mesoporous Structure and Morphology of Hydroxyapatite Powders.

Mesoporous hydroxyapatite (HA) materials demonstrate advantages as catalysts and as support systems for catalysis, as adsorbent materials for removing contamination from soil and water, and as nanocarriers of functional agents for bone-related therapies. The present research demonstrates the possibility of the enlargement of the Brunauer-Emmett-Teller specific surface area (SSA), pore volume, and average pore diameter via changing the synthesis medium and ripening the material in the mother solution after the precipitation processes have been completed. HA powders were investigated via chemical analysis, X-ray diffraction analysis, Fourier-transform IR spectroscopy, transmission electron microscopy (TEM), and scanning (SEM) electron microscopy. Their SSA, pore volume, and pore-size distributions were determined via low-temperature nitrogen adsorption measurements, the zeta potential was established, and electron paramagnetic resonance (EPR) spectroscopy was performed. When the materials were synthesized in water-ethanol and water-acetone media, the SSA and total pore volume were 52.1 m2g-1 and 116.4 m2g-1, and 0.231 and 0.286 cm3g-1, respectively. After ripening for 21 days, the particle morphology changed, the length/width aspect ratio decreased, and looser and smaller powder agglomerates were obtained. These changes in their characteristics led to an increase in SSA for the water and water-ethanol samples, while pore volume demonstrated a multiplied increase for all samples, reaching 0.593 cm3g-1 for the water-acetone sample.

Effects of platelets activated by different agonists on fibrin formation and thrombin generation.

Activated platelets possess procoagulant activity expressing on their surface phosphatidylserine (PS), a substrate for assembling coagulation complexes. We examined the effects of platelets activated by different agonists on fibrin formation and thrombin generation and compared these effects with each other and with PS expression. Modified plasma recalcification assay was developed to assess platelet effects on fibrin formation. Washed human platelets were left intact or activated by A23187 ionophore, collagen, arachidonic acid, ADP or TRAP (Thrombin Receptor Activating Peptide) and spun down in 96-well plates. Plasma was then added, recalcified, and fibrin formation was monitored by light absorbance. Platelets prepared in the same way were tested for their effect on thrombin generation. PS expression was evaluated by flow cytometry using annexin V staining. Platelets significantly accelerated fibrin formation and thrombin generation. They shortened lag phase and increased maximum rate of plasma clotting, and increased peak and maximum rate of thrombin generation. In both tests platelets were presumably activated by endogenous thrombin formed in plasma after triggering coagulation reactions. However, pretreatment with exogenous agonists additionally increased platelet procoagulant activity. It reached the maximum after incubation with A23187, being lower with collagen and arachidonic acid and minimum with ADP and TRAP (the latter might be ineffective due to competition with endogenous thrombin). The effects of platelets activated by different agonists on fibrin formation and thrombin generation correlate with each other and correspond to PS expression on their surface.

Why was the study done? Platelets and blood coagulation system interact with each other in hemostasis and intravascular thrombosis.Direct platelet effects on fibrin formation (plasma clotting), the final stage of blood coagulation cascade, have been insufficiently studied.The work is aimed at developing a method for studying platelet participation in fibrin formation in blood plasma and investigating the influence of platelet agonists on this reaction.What is new? Platelets significantly accelerate fibrin formation and their activation with various agonists (thrombin, collagen, arachidonic acid) enhances these effects.Effects of platelets on fibrin formation correlated with their ability to stimulate thrombin generation in blood plasmaEffects of platelets on fibrin formation and thrombin generation correlated with the level of phosphatidylserine exposure on their surfaceWhat is the impact? This study provides further evidence that platelet procоagulant effects on fibrin formation should be considered in investigations of platelet involvement in hemostatic and thrombotic reactions and in the evaluation of the efficacy of antiplatelet drugs.

Clinical comparison of manual and laser-cut corneal tunnel for intrastromal air injection in femtosecond laser-assisted deep anterior lamellar keratoplasty (DALK).

PURPOSE: The most crucial step in deep anterior lamellar keratoplasty (DALK) is to achieve a bare Descemet's membrane. We aimed to assess a new femtosecond laser software that allows for a precise intrastromal tunnel creation for big bubble (BB) air injection using a real-time microscope-integrated optical coherence tomography. MATERIALS AND METHODS: A retrospective review of 61 eyes of 61 patients with keratoconus. Before introducing the new software update, DALK was performed using a partial-assisted femtosecond laser (partial-thickness circular cut followed by a lamellar cut) with manual intrastromal tunnel creation (partial FS-DALK group). After the software update, the femtosecond laser created the intrastromal tunnel (full FS-DALK group). RESULTS: In the full FS-DALK group, the BB's formation was significantly higher (64.3% vs. 36.4%, p = 0.04), and surgery time was shorter (21.8 ± 5.1 vs. 25.6 ± 6.8 min, p = 0.025) than in the partial FS-DALK. Penetrating keratoplasty conversion rate (7.1% vs. 15.1%, p = 0.432) was similar between the groups. Both groups showed statistically significant improvement in uncorrected and corrected distance visual acuity, central corneal thickness, surface asymmetry, and regularity indices. Endothelial cell density loss at 12 and 18 months was lower in the full compared with the partial FS-DALK group (12 months:10.0% vs. 16; 18 months: 10.7 vs. 16.5%, p < 0.001 for both comparisons). CONCLUSIONS: Creating the intrastromal guiding tunnel using FS laser for air injection resulted in a higher rate of BB formation, reduced long-term endothelial cell loss, and operating room time.

Dicarbonyl-Modified Low-Density Lipoproteins Are Key Inducers of LOX-1 and NOX1 Gene Expression in the Cultured Human Umbilical Vein Endotheliocytes.

Expression of LOX-1 and NOX1 genes in the human umbilical vein endotheliocytes (HUVECs) cultured in the presence of low-density lipoproteins (LDL) modified with various natural dicarbonyls was investigated for the first time. It was found that among the investigated dicarbonyl-modified LDLs (malondialdehyde (MDA)-modified LDLs, glyoxal-modified LDLs, and methylglyoxal-modified LDLs), the MDA-modified LDLs caused the greatest induction of the LOX-1 and NOX1 genes, as well as of the genes of antioxidant enzymes and genes of proapoptotic factors in HUVECs. Key role of the dicarbonyl-modified LDLs in the molecular mechanisms of vascular wall damage and endothelial dysfunction is discussed.

Single-Cell Gene Expression Analysis Revealed Immune Cell Signatures of Delta COVID-19.

The coronavirus disease 2019 (COVID-19) is accompanied by a cytokine storm with the release of many proinflammatory factors and development of respiratory syndrome. Several SARS-CoV-2 lineages have been identified, and the Delta variant (B.1.617), linked with high mortality risk, has become dominant in many countries. Understanding the immune responses associated with COVID-19 lineages may therefore aid the development of therapeutic and diagnostic strategies. Multiple single-cell gene expression studies revealed innate and adaptive immunological factors and pathways correlated with COVID-19 severity. Additional investigations covering host-pathogen response characteristics for infection caused by different lineages are required. Here, we performed single-cell transcriptome profiling of blood mononuclear cells from the individuals with different severity of the COVID-19 and virus lineages to uncover variant specific molecular factors associated with immunity. We identified significant changes in lymphoid and myeloid cells. Our study highlights that an abundant population of monocytes with specific gene expression signatures accompanies Delta lineage of SARS-CoV-2 and contributes to COVID-19 pathogenesis inferring immune components for targeted therapy.

Selective Cytotoxicity and Changes in Protein Expression of T24 Bladder Carcinoma Permanent Cell Line after Treatment with Hemocyanins.

BACKGROUND: Some molluscan hemocyanins (Hcs) have significant immunological and antitumor potential, enabling their application in oncology. The antitumor activity of Hcs from marine snails Rapana venosa (RvH), giant keyhole limpet Megathura crenulata (KLH) and garden snails Helix lucorum (HlH), as well as their different derivatives, were studied in vitro on a permanent T24 cell line of bladder cancer and normal urothelial cell line HL 10/29 compared to doxorubicin. METHODS: The antiproliferative activity of the tested Hcs was determined using the WST-1 assay and BrdU ELISA assay. Morphological changes in both urothelial cell lines were confirmed by fluorescence microscopy. The proteomic analysis of a bladder cancer cell line before and after treatment with functional unit (FU) ßc-HlH-h using two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) and mass spectrometry revealed differences in the expression of some proteins. RESULTS: Studies prove that the T24 tumor cell line is dose- and time-dependent, sensitive to the action of the tested isoforms, and it glycosylated FU of these hemocyanins. Selective inhibition of T24 cell growth was observed after incubation with structural subunits (ßc-HlH, RvHI and RvHII) and FUs (ßc-HlH-h and RvHII-e). Additionally, fluorescent microphotographs did not show apoptotic or necrotic alterations in the normal urothelial cell line HL 10/29. The FU ßc-HlH-h demonstrated the highest antiproliferative effect (similarly to doxorubicin), in which predominantly apoptotic and less late apoptotic or necrotic changes in the tumor cells were observed. Several downand up-regulated proteins identified by proteome analysis may be associated with the apoptosis pathway. CONCLUSION: The present study illustrated the selectivity of the cytotoxic effect of Hcs against the Т24 cancer cell line. This is the first report of protein expression in T24 human bladder cancer cells under the influence of FU ßc-HlH-h. That is probably due to the specific oligosaccharide structures rich in methylated hexoses exposed on the surface of ßc-HlH-h.

Light-to-Heat Converting ECM-Mimetic Nanofiber Scaffolds for Neuronal Differentiation and Neurite Outgrowth Guidance.

The topological cues of fibrous scaffolds (in particular extracellular matrix (ECM)-mimetic nanofibers) have already proven to be a powerful tool for influencing neuronal morphology and behavior. Remote photothermal optical treatment provides additional opportunities for neuronal activity regulation. A combination of these approaches can provide "smart" 3D scaffolds for efficient axon guidance and neurite growth. In this study we propose two alternative approaches for obtaining biocompatible photothermal scaffolds: surface coating of nylon nanofibers with light-to-heat converting nanoparticles and nanoparticle incorporation inside the fibers. We have determined photoconversion efficiency of fibrous nanomaterials under near infrared (NIR) irradiation, as well as biocompatible photothermal treatment parameters. We also measured photo-induced intracellular heating upon contact of cells with a plasmonic surface. In the absence of NIR stimulation, our fibrous scaffolds with a fiber diameter of 100 nm induced an increase in the proportion of ß3-tubulin positive cells, while thermal stimulation of neuroblastoma cells on nanoparticles-decorated scaffolds enhanced neurite outgrowth and promoted neuronal maturation. We demonstrate that contact guidance decorated fibers can stimulate directional growth of processes of differentiated neural cells. We studied the impact of nanoparticles on the surface of ECM-mimetic scaffolds on neurite elongation and axonal branching of rat hippocampal neurons, both as topographic cues and as local heat sources. We show that decorating the surface of nanofibers with nanoparticles does not affect the orientation of neurites, but leads to strong branching, an increase in the number of neurites per cell, and neurite elongation, which is independent of NIR stimulation. The effect of photothermal stimulation is most pronounced when cultivating neurons on nanofibers with incorporated nanoparticles, as compared to nanoparticle-coated fibers. The resulting light-to-heat converting 3D materials can be used as tools for controlled photothermal neuromodulation and as "smart" materials for reconstructive neurosurgery.

In vitro Susceptibility to ß-Lactam Antibiotics and Viability of Neisseria gonorrhoeae Strains Producing Plasmid-Mediated Broad- and Extended-Spectrum ß-Lactamases.

Neisseria gonorrhoeae plasmids can mediate high-level antimicrobial resistance. The emergence of clinical isolates producing plasmid ß-lactamases that can hydrolyze cephalosporins, the mainstay treatment for gonorrhea, may be a serious threat. In this work, N. gonorrhoeae strains producing plasmid-mediated broad- and extended-spectrum ß-lactamases (ESBLs) were obtained in vitro, and their viability and ß-lactam antibiotic susceptibility were studied. Artificial pbla TEM-1 and pbla TEM-20 plasmids were constructed by site-directed mutagenesis from a pbla TEM-135 plasmid isolated from a clinical isolate. Minimum inhibitory concentration (MIC) values for a series of ß-lactam antibiotics, including benzylpenicillin, ampicillin, cefuroxime, ceftriaxone, cefixime, cefotaxime, cefepime, meropenem, imipenem, and doripenem, were determined. The N. gonorrhoeae strain carrying the pbla TEM-20 plasmid exhibited a high level of resistance to penicillins and second-fourth-generation cephalosporins (MIC ≥2 mg/L) but not to carbapenems (MIC ≤0.008 mg/L). However, this strain stopped growing after 6 h of culture. The reduction in viability was not associated with loss of the plasmid but can be explained by the presence of the plasmid itself, which requires additional reproduction costs, and to the expression of ESBLs, which can affect the structure of the peptidoglycan layer in the cell membrane. Cell growth was mathematically modeled using the generalized Verhulst equation, and the reduced viability of the plasmid-carrying strains compared to the non-plasmid-carrying strains was confirmed. The cell death kinetics of N. gonorrhoeae strains without the pbla TEM-20 plasmid in the presence of ceftriaxone can be described by a modified Chick-Watson law. The corresponding kinetics of the N. gonorrhoeae strain carrying the pbla TEM-20 plasmid reflected several processes: the hydrolysis of ceftriaxone by the TEM-20 ß-lactamase and the growth and gradual death of cells. The demonstrated reduction in the viability of N. gonorrhoeae strains carrying the pbla TEM-20 plasmid probably explains the absence of clinical isolates of ESBL-producing N. gonorrhoeae.