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DNA sequence changes induced by two nitric oxide donor drugs in the supF assay.

To refine our understanding of the mutational spectra one might expect on exposure of human cells to nitric oxide (NO), we have treated the plasmid pSP189 at pH 7.4 with two compounds that generate NO spontaneously in solution, and then sequenced the mutations found when the treated plasmid was transfected into human Ad293 cells and allowed to replicate. G.C-->A.T transitions were the most abundant mutation observed with these NO donor drugs, whereas in previous work, A.T-->G.C transitions predominated when nitric oxide gas was bubbled through the plasmid solution under otherwise identical con

In vitro muscle contractures induced by halothane and suxamethonium. II: Human skeletal muscle from normal and malignant hyperthermia susceptible patients.

The role of lipolysis in halothane-induced contractures of human skeletal muscle was examined using three inhibitors of phospholipase A2 (PLA2) activity (quinacrine, spermine and indomethacin) and exogenously administered PLA2. In addition, we examined the effects of the same PLA2 inhibitors on contractures induced by halothane in combination with suxamethonium. The studies were conducted on directly stimulated muscle strips isolated from biopsies from patients diagnosed as MH susceptible, or not susceptible, by the halothane contracture test. The liberation of fatty acids from skeletal muscle…

Polyamines and nucleic acids in gestational trophoblastic tumors.

To test the relationship between tumor malignancy and content and distribution of polyamines and nucleic acids, 2 forms of human gestational trophoblastic tumors were examined: the hydatidiform mole (self-limited form) and the human chorio-carcinoma (invasive form) xenografted into nude mice. The results indicate that there are 2 significant differences between the choriocarcinoma and the mole: 1) the choriocarcinoma is characterized by increased polyamine and nucleic acid levels, 2) tissues differ in their putrescine:spermidine and spermidine:spermine ratios. There is an increase in polyamine…

Functional and Biochemical Characterization of Spermidine Synthase CauSpe3 from Candidozyma auris.

Polyamines, putrescine, spermidine and spermine, are essential polycationic metabolites present in all eukaryotic cells, where they regulate fundamental processes including nucleic acid stabilization, translation, and stress responses. Spermidine synthase (SPDS), a member of the aminopropyltransferase (APT) family, catalyzes the transfer of an aminopropyl group from decarboxylated S-adenosylmethionine (dc-SAM) to putrescine to form spermidine. Although genomic analyses predict the presence of SPDS homologs in multiple fungal species, polyamine biosynthesis has not been experimentally character…

Knockdown of Smox Protects Against Cerebral Ischemia/Reperfusion Injury by Suppressing Neuronal Autophagy via the AKT/AMPK/mTOR Phosphorylation Pathway.

BACKGROUND: Stroke is a major cause of morbidity and mortality, characterized by neuronal damage and complex cell death pathways. This study aimed to investigate the protective role of spermine oxidase (Smox) in ischemic stroke and its effect on neuronal autophagy. METHODS: We employed transient middle cerebral artery occlusion (tMCAO) models and oxygen-glucose deprivation/reoxygenation (OGD/R) experiments in HT22 cells to explore the protective effects of Smox knockdown against ischemic injury and to evaluate changes in autophagy. RESULTS: Smox levels were significantly elevated following s…

Impact of ferroptosis on preeclampsia: A review.

Preeclampsia (PE) is usually associated with the accumulation of reactive oxygen species (ROS) resulting from heightened oxidative stress (O … A synthetase long-chain family member 4, lysophosphatidylcholine acyl-transferase 3, and spermidine/spermine N1-acetyltransferase 1, trophoblasts become more susceptible to OS and ROS damage. In stage 1, the injured trophoblasts exhibit poor invasion and incomplete uterine spiral artery remodeling caused by ferroptosis, leading to placental ischemia and hy …

Age-related vulnerability to nigral dopaminergic degeneration in rats via Zn2+-permeable GluR2-lacking AMPA receptor activation.

On the basis of the evidence that extracellular Zn2+ influx induced with AMPA causes Parkinson's syndrome in rats that apomorphine-induced m … tion of either extracellular (CaEDTA) or intracellular (ZnAF-2DA) Zn2+ chelators. 1-Naphthyl acetyl spermine (NASPM), a selective blocker of Ca2+- and Zn2+-permeable GluR2-lacking AMPA receptors blocked increase in intracellular Zn2+ in the SNpc of aged rats followed by rescuing nigral dopaminergic degeneration. The present study indicates that intracellul …

Formation of biogenic amines in fish: Dietary intakes and health risk assessment.

Biogenic amines (BAs) are toxicants that are produced during the proteolytic activities of some microorganisms, or naturally during the meta … d results indicated the formation of histamine (HIS), tyramine (TYR), cadaverine (CAD), putrescine, spermine, and spermidine at different concentrations. Tilapia had the lowest concentration levels for the different BAs. In contrast, mackerel and tuna had the highest concentrations of BAs. Total biogenic amines (TBAs) showed significant positive correlatio …

Усилители трансдукции позволяют эффективно использовать аденовирус человека 5-го типа для передачи генов в мультипотенциальные мезенхимальные ячейки.

Множественные месенхимальные стромальные клетки человека в настоящее время разрабатываются в качестве клеточной терапии для различных видов применения, включая регенеративную медицину, иммунную модуляцию и лечение рака. Биологические свойства ЧВОК могут быть дополнительно модернизированы с помощью генной инженерии. Векторы вирусов, основанные на аденовирусе человека типа 5 (HAdV-5), относятся к наиболее часто используемым типам векторов для генетической модификации клеток человека in vitro и in vivo. Однако из-за отсутствия основного крепежного рецептора cexsackievirus и аденовирусного рецепто

Совпадение в аннотации оригинала
Human multipotent mesenchymal stromal cells (hMSCs) are currently developed as cell therapeutics for different applications, including regen … issue-derived hMSCs. Polybrene, poly-l-lysine, human lactoferrin, human blood coagulation factor X, spermine, and spermidine enabled high eGFP expression levels in hMSCs. Importantly, hMSCs treated with enhancers were not affected in their migration behavior, which is a key requisite for many therapeutic applications. Exemplary, strongly increased expressi …

Engineering of SPECT/Photoacoustic Imaging/Antioxidative Stress Triple-Function Nanoprobe for Advanced Mesenchymal Stem Cell Therapy of Cerebral Ischemia.

The precise transplantation, long-term tracking, and maintenance of stem cells with maximizing therapeutic effect are significant challenges in stem cell-based therapy for stroke treatment. In this study, a unique core-shell labeling nanoagent was prepared by encapsulating a cobalt protoporphyrin IX (CoPP)-loaded mesoporous silica nanoparticle (CPMSN) into a 125I-conjugated/spermine-modified dextran polymer (125I-SD) by microfluidics for mesenchymal stem cell (MSC) tracking and activity maintenance. The CPMSN core not only exhibits excellent photoacoustic (PA) imaging performance induced by th…

[Polyamines of urogenital tract men as factors of apoptosis regulation spermatozoids].

UNLABELLED: The aim of the study was to compare the content of polyamines (spermine and spermidine) in the seminal plasma of men of different fertility and to reveal the relationship between their level in sperm and the presence of markers of apoptosis in gametes. MATERIALS AND METHODS: ejaculates of 34 fertile men and 40 infertile men with various forms of subfertility between the ages of 22 and 40 were examined. The determination of polyamines was carried out by electrophoretic fractionation in an agar gel. As markers of apoptosis, externalization of phosphatidylserine (PS) to the external …

Salicylic acid differently impacts ethylene and polyamine synthesis in the glycophyte Solanum lycopersicum and the wild-related halophyte Solanum chilense exposed to mild salt stress.

This study aimed to determine the effects of exogenous application of salicylic acid (SA) on the toxic effects of salt in relation to ethylene and polyamine synthesis, and to correlate these traits with the expression of genes involved in ethylene and polyamine metabolism in two tomato species differing in their sensitivity to salt stress, Solanum lycopersicum cv Ailsa Craig and its wild salt-resistant relative Solanum chilense. In S. chilense, treatment with 125 mM NaCl improved plant growth, increased production of ethylene, endogenous salicylic acid and spermine. The production was related …

SiRNA-mediated in vivo gene knockdown by acid-degradable cationic nanohydrogel particles.

Cationic nanohydrogel particles have become an attractive tool for systemic siRNA delivery, but improvement of their in vivo tolerance is de … itro gene knockdown for the acid-degradable cationic nanoparticles compared to their non-degradable spermine analogues. In a murine liver fibrosis model enhanced carrier and payload accumulation in the fibrotic tissue facilitated sequence-specific gene knockdown and prevented fibrosis progression. Long-term monitoring of the carrier in the body showed an e …

Inhibition of polyamine formation antagonizes vascular smooth muscle cell proliferation and preserves the contractile phenotype.

The polyamines putrescine, spermidine and spermine play essential roles in cell proliferation and migration, two processes involved in the development of vascular disease. Thus, intervention with polyamine formation may represent a way to inhibit unwanted vascular smooth muscle cell (VSMC) proliferation. The aim of the present study was to assess the importance of polyamines for VSMC proliferation and vascular contractility. The rate-limiting step in polyamine biosynthesis is catalysed by ornithine decarboxylase (ODC). Treatment with α-difluoromethylornithine (DFMO), an irreversible inhibitor …

Simultaneous determination of sixteen underivatized biogenic amines in human urine by HPLC-MS/MS.

The broad group of biogenic amines includes polyamines and catecholamines, whose presence in human tissues and biological fluids can give im … (norepinephrine), norephedrine, octopamine, 2-phenylethylamine, putrescine, serotonin, spermidine, spermine, tryptamine, and tyramine. The method does not require any derivatization step. To guarantee the maximum of sensitivity, the mass spectrometer works in selected reaction monitoring mode, monitoring for each analyte the two most intensive transitions …

Characterization of polyamine homeostasis in l-ornithine-induced acute pancreatitis in rats.

OBJECTIVES: l-Ornithine is a precursor of polyamine synthesis that is essential for cell survival. In contrast, intraperitoneal (IP) adminis … 168 hours for determinations of polyamines and activities of ornithine decarboxylase and spermidine/spermine N(1)-acetyltransferase (SSAT). Pancreatitis severity was assessed by measuring standard laboratory and histological parameters. RESULTS: Injection of l-ornithine paradoxically induced pancreatic spermidine catabolism, possibly via activation of SSA …

Comparative analysis of the pharmacology of GluR1 in complex with transmembrane AMPA receptor regulatory proteins gamma2, gamma3, gamma4, and gamma8.

AMPA receptors (AMPARs) mediate the majority of fast synaptic transmission in the CNS of vertebrates. They are believed to be associated wit … ept gamma4) reduce the ion channel block by the synthetic Joro spider toxin analog 1-naphthylacetyl spermine (NASP). In addition, TARPs increase the permeability of the receptor to calcium, indicating that TARPs directly modulate important ion pore properties. In summary, the data presented herein will illustrate and help to understand the previously unexp …

Regional and temporal alterations of ODC/polyamine system during ALS-like neurodegenerative motor syndrome in G93A transgenic mice.

Natural polyamines (putrescine, spermidine and spermine) are ubiquitous molecules known to regulate a number of physiological processes and suspected to play a role also in various pathological conditions. Changes in polyamine levels and in their biosynthetic enzymes have been described for some neurodegenerative diseases but the available data are incomplete and somewhat contradictory. We report here alterations of the key enzyme of the polyamine pathway, ornithine decarboxylase (ODC) catalytic activity and polyamine levels in different CNS areas from SOD1 G39A transgenic mice, an animal mode…

Inhibitors of polyamine metabolism: review article.

The identification of increased polyamine concentrations in a variety of diseases from cancer and psoriasis to parasitic infections has led … ke. This coupled with increased activity of the catabolic enzymes, polyamine oxidase and spermidine/spermine N1-acetyltransferase, and increased polyamine export has made the analogues more effective in depleting polyamine pools. Recently, the identification of a new oxidase (PAO-h1/SMO) in polyamine catabolism and evidence of induction of both PAO and PAO …

Role of an inducible single-domain hemoglobin in mediating resistance to nitric oxide and nitrosative stress in Campylobacter jejuni and Campylobacter coli.

Campylobacter jejuni expresses two hemoglobins, each of which exhibits a heme pocket and structural signatures in common with vertebrate and plant globins. One of these, designated Cgb, is homologous to Vgb from Vitreoscilla stercoraria and does not possess the reductase domain seen in the flavohemoglobins. A Cgb-deficient mutant of C. jejuni was hypersensitive to nitrosating agents (S-nitrosoglutathione [GSNO] or sodium nitroprusside) and a nitric oxide-releasing compound (spermine NONOate). The sensitivity of the Cgb-deficient mutant to methyl viologen, hydrogen peroxide, and organic peroxid…