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1.
Front Microbiol ; 13: 960937, 2022.
Article in English | MEDLINE | ID: mdl-36238585

ABSTRACT

Botulinum neurotoxin (BoNT) is one of the most dangerous bacterial toxins and a potential biological weapon component. BoNT mechanism of pathological action is based on inhibiting the release of neurotransmitters from nerve endings. To date, anti-BoNT therapy is reduced to the use of horse hyperimmune serum, which causes many side effects, as well as FDA-approved drug BabyBig which consists of human-derived anti-BoNT antibodies (IgG) for infant botulinum treatment. Therapeutics for botulism treatment based on safer monoclonal antibodies are undergoing clinical trials. In addition, agents have been developed for the specific prevention of botulism, but their effectiveness has not been proved. In this work, we have obtained a recombinant adeno-associated virus (rAAV-B11-Fc) expressing a single-domain antibody fused to the human IgG Fc-fragment (B11-Fc) and specific to botulinum toxin type A (BoNT/A). We have demonstrated that B11-Fc antibody, expressed via rAAV-B11-Fc treatment, can protect animals from lethal doses of botulinum toxin type A, starting from day 3 and at least 120 days after administration. Thus, our results showed that rAAV-B11-Fc can provide long-term expression of B11-Fc-neutralizing antibody in vivo and provide long-term protection against BoNT/A intoxication. Consequently, our study demonstrates the applicability of rAAV expressing protective antibodies for the prevention of intoxication caused by botulinum toxins.

2.
Clin Ther ; 43(10): 1720-1734, 2021 10.
Article in English | MEDLINE | ID: mdl-34479761

ABSTRACT

PURPOSE: To compare the efficacy and safety of ketoprofen plasters and diclofenac plasters after 3 weeks of administration in patients with osteoarthritis-related knee pain. METHODS: This multicenter, randomized, active-controlled, open-label, parallel-group, noninferiority phase III study randomized 236 adults with osteoarthritis-related knee pain for 3 weeks with ketoprofen plaster 30 mg twice daily (n = 118) or diclofenac plaster 15 mg once daily (n = 118). The primary efficacy end point was the mean change from baseline to week 3 in the mean knee pain intensity score during walking, as measured by a 100-mm visual analog scale with a predefined noninferiority margin of 10.0 mm. Secondary end points included changes in knee pain intensity score during walking (weeks 1 and 2) and at rest (weeks 1, 2, and 3), Knee Injury and Osteoarthritis Outcome Score, Patient Global Impression of Improvement scale assessments, and frequency of rescue medication use after 2 and 3 weeks of treatment. FINDINGS: A total of 223 patients (115 in the ketoprofen group and 108 in the diclofenac group) were included in the per-protocol analysis. After 3 weeks of treatment, the least squares mean change from baseline in knee pain intensity scores during walking was -35.9 (95% CI, -39.7 to -32.2) in the ketoprofen group and -31.7 (95% CI, -35.5 to -27.9) in the diclofenac group, with noninferiority found (least squares mean difference, -4.2; 95% CI, -9.6 to 1.1). Ketoprofen significantly (P < 0.05) reduced the pain intensity score at rest after 2 and 3 weeks of treatment compared with diclofenac. No statistically significant difference was found between the groups in terms of changes in pain intensity score during walking at weeks 1, 2, and 3. The mean Patient Global Impression of Improvement score was statistically significant (P < 0.001) in favor of ketoprofen after 2 and 3 weeks of treatment. In addition, the Knee Injury and Osteoarthritis Outcome Score improved in both groups, and no statistically significant difference was found between the groups in terms of frequency of rescue medication use. The overall adverse event profile of the groups was similar, and no difference was found in skin reaction rates between the 2 groups. IMPLICATIONS: Ketoprofen plasters can be effectively and safely administered to patients with osteoarthritis-related knee pain.


Subject(s)
Ketoprofen , Osteoarthritis, Knee , Osteoarthritis , Adult , Anti-Inflammatory Agents, Non-Steroidal/adverse effects , Diclofenac/adverse effects , Double-Blind Method , Humans , Ketoprofen/adverse effects , Knee Joint , Osteoarthritis/drug therapy , Osteoarthritis, Knee/drug therapy , Pain/drug therapy , Treatment Outcome
3.
Sensors (Basel) ; 20(18)2020 Sep 18.
Article in English | MEDLINE | ID: mdl-32961965

ABSTRACT

In this paper, we consider the process of fiber vortex modes generation using chiral periodic structures that include both chiral optical fibers and chiral (vortex) fiber Bragg gratings (ChFBGs). A generalized theoretical model of the ChFBG is developed including an arbitrary function of apodization and chirping, which provides a way to calculate gratings that generate vortex modes with a given state for the required frequency band and reflection coefficient. In addition, a matrix method for describing the ChFBG is proposed, based on the mathematical apparatus of the coupled modes theory and scattering matrices. Simulation modeling of the fiber structures considered is carried out. Chiral optical fibers maintaining optical vortex propagation are also described. It is also proposed to use chiral fiber-optic periodic structures as sensors of physical fields (temperature, strain, etc.), which can be applied to address multi-sensor monitoring systems due to a unique address parameter-the orbital angular momentum of optical radiation.

4.
Toxins (Basel) ; 11(8)2019 08 07.
Article in English | MEDLINE | ID: mdl-31394847

ABSTRACT

The bacterium Clostridium botulinum is the causative agent of botulism-a severe intoxication caused by botulinum neurotoxin (BoNT) and characterized by damage to the nervous system. In an effort to develop novel C. botulinum immunotherapeutics, camelid single-domain antibodies (sdAbs, VHHs, or nanobodies) could be used due to their unique structure and characteristics. In this study, VHHs were produced using phage display technology. A total of 15 different monoclonal VHHs were selected based on their comlementarity-determining region 3 (CDR3) sequences. Different toxin lethal dose (LD50) challenges with each selected phage clone were conducted in vivo to check their neutralizing potency. We demonstrated that modification of neutralizing VHHs with a human immunoglobulin G (IgG)1 Fc (fragment crystallizable) fragment (fusionbody, VHH-Fc) significantly increased the circulation time in the blood (up to 14 days). At the same time, VHH-Fc showed the protective activity 1000 times higher than monomeric form when challenged with 5 LD50. Moreover, VHH-Fcs remained protective even 14 days after antibody administration. These results indicate that this VHH-Fc could be used as an effective long term antitoxin protection against botulinum type A.


Subject(s)
Botulinum Toxins, Type A/immunology , Immunoglobulin Fc Fragments/immunology , Recombinant Fusion Proteins/immunology , Amino Acid Sequence , Animals , Antibodies, Neutralizing/immunology , Camelids, New World , Enzyme-Linked Immunosorbent Assay , Humans , Mice , Recombinant Fusion Proteins/administration & dosage , Recombinant Fusion Proteins/chemistry
5.
Curr Aging Sci ; 10(1): 49-55, 2017.
Article in English | MEDLINE | ID: mdl-27659262

ABSTRACT

BACKGROUND: The present study was aimed to identify how age-related changes in some physiological and biochemical systems are related to changes in the life span of rats with long-term pineal gland hypo- and hyperfunction induced by constant light and constant darkness, respectively. METHODS: At the age of 25 days the rats were randomly divided into 3 groups: standard light/dark regimen (LD), constant light (LL) and constant darkness (DD). Age-related Antioxidant System (AOS) changes in liver tissues, alteration of immunoreactivity in blood smears were investigated, pubescence and lifespan of the animals were determined. RESULTS: Modification of the level of melatonin synthesis induced by constant light results in interrelated rearrangements in the functioning of the investigated physiological systems. Elevated activity of the antioxidant system extends the lifespan, while at the same time slowing down pubescence and altering the morpho-functional properties of leukocytes in blood. CONCLUSION: The absence of light/dark alternation (constant light and constant darkness) affects only those physiological indices that follow the organism's circadian rhythms (Activity of Antioxidant Enzymes (AOE), levels of individual immune system cell types), whereas changes in the parameters not governed by circadian fluctuations (vitamin concentrations, pubescence, and aging) depend on the level of melatonin produced by the pineal gland.


Subject(s)
Light , Longevity/radiation effects , Aging/immunology , Aging/metabolism , Aging/radiation effects , Animals , Antioxidants/metabolism , Darkness , Female , Liver/metabolism , Longevity/immunology , Longevity/physiology , Male , Melatonin/metabolism , Rats , Reactive Oxygen Species/metabolism
6.
Biogerontology ; 14(4): 401-9, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23784085

ABSTRACT

Effect of light regimens (standard 12:12 light/dark, constant light, natural lightning of the north-west of Russia) and that of melatonin on the development of metabolic syndrome during aging of rats was studied. It was found out that during the process of aging of rats kept in the conditions of the broken rhythm of day and night, different disturbances of metabolism in the form of abdominal obesity, hyperinsulinemia, hypercholesterolemia, hyperglycemia, hyperbetalipoproteinemia and glycosuria occurred. These disturbances can be considered to be metabolic syndrome or the syndrome of insulin resistance. The use of melatonin at night time starting in the rats of 4 month old allowed to decrease the age metabolism disorders in the rats. This fact indirectly proves the insufficiency of this hormone in human in the conditions of natural lighting of the north-west of Russia.


Subject(s)
Darkness , Light , Melatonin/pharmacology , Metabolic Syndrome/prevention & control , Animals , Blood Glucose/analysis , C-Peptide/analysis , Circadian Rhythm , Male , Rats , Russia
7.
PLoS One ; 8(3): e58705, 2013.
Article in English | MEDLINE | ID: mdl-23527009

ABSTRACT

Recent studies have shown that bovine leukemia virus (BLV) sequences can be classified into seven distinct genotypes based on full gp51 sequence. This classification was based on available sequence data that mainly represented the BLV population that is circulating in cattle from the US and South America. In order to aid with a global perspective inclusion of data from Eastern Europe is required. In this study we examined 44 BLV isolates from different geographical regions of Poland, Belarus, Ukraine, and Russia. Phylogenetic analysis based on a 444bp fragment of env gene revealed that most of isolates belonged to genotypes 4 and 7. Furthermore, we confirmed the existence of a new genotype, genotype 8, which was highly supported by phylogenetic computations. A significant number of amino acid substitutions were found in the sequences of the studied Eastern European isolates, of which 71% have not been described previously. The substitutions encompassed mainly the C-part of the CD4+ epitope, zinc binding peptide region, CD8+ T cell epitope, and overlapping linear epitope E. These observations highlight the use of sequence data to both elucidate phylogenetic relationships and the potential effect on serological detection of geographically diverse isolates.


Subject(s)
Leukemia Virus, Bovine/genetics , Amino Acid Sequence , Animals , Antigens, Viral/genetics , Cattle , Enzootic Bovine Leukosis/virology , Epitopes/genetics , Europe, Eastern , Genes, env , Genetic Variation , Genotype , Leukemia Virus, Bovine/classification , Leukemia Virus, Bovine/isolation & purification , Molecular Sequence Data , Phylogeny , Siberia
8.
Curr Aging Sci ; 5(3): 170-7, 2012 Dec.
Article in English | MEDLINE | ID: mdl-23237593

ABSTRACT

Light-at-night has become an increasing and essential part of the modern lifestyle and leads to a number of health problems, including excessive body mass index, cardiovascular diseases, diabetes, and cancer. The International Agency for Research on Cancer (IARC) Working Group concluded that "shift-work that involves circadian disruption is probably carcinogenic to humans" (Group 2A) [1]. According to the circadian disruption hypothesis, light-at-night might disrupt the endogenous circadian rhythm and specifically suppress nocturnal production of the pineal hormone melatonin and its secretion into the blood. We evaluated the effect of various light/dark regimens on the survival, life span, and spontaneous and chemical carcinogenesis in rodents. Exposure to constant illumination was followed by accelerated aging and enhanced spontaneous tumorigenesis in female CBA and transgenic HER-2/neu mice. In male and female rats maintained at various light/dark regimens (standard 12:12 light/dark [LD], the natural light [NL] of northwestern Russia, constant light [LL], and constant darkness [DD]) from the age of 25 days until natural death, it was found that exposure to NL and LL regimens accelerated age-related switch-off of the estrous function (in females), induced development of metabolic syndrome and spontaneous tumorigenesis, and shortened life span both in male and females rats compared to the standard LD regimen. Melatonin given in nocturnal drinking water prevented the adverse effect of the constant illumination (LL) and natural light (NL) regimens on the homeostasis, life span, and tumor development both in mice and rats. The exposure to the LL regimen accelerated colon carcinogenesis induced by 1,2-dimethylhydrazine (DMH) in rats, whereas the treatment with melatonin alleviated the effects of LL. The maintenance of rats at the DD regimen inhibited DMH-induced carcinogenesis. The LL regimen accelerated, whereas the DD regimen inhibited both mammary carcinogenesis induced by N-nitrosomethylurea and transplacental carcinogenesis induced by N-nitrosoethylurea in rats. Treatment with melatonin prevented premature aging and tumorigenesis in rodents. The data found in the literature and our observations suggest that the use of melatonin would be effective for cancer prevention in humans at risk as a result of light pollution.


Subject(s)
Aging/metabolism , Circadian Rhythm/radiation effects , Light/adverse effects , Neoplasms, Radiation-Induced/metabolism , Photoperiod , Age Factors , Aging/genetics , Aging/pathology , Animals , Anticarcinogenic Agents/pharmacology , Blindness/epidemiology , Cell Transformation, Neoplastic/metabolism , Cell Transformation, Neoplastic/radiation effects , Female , Humans , Male , Melatonin/pharmacology , Mice , Neoplasms, Radiation-Induced/epidemiology , Neoplasms, Radiation-Induced/genetics , Neoplasms, Radiation-Induced/pathology , Neoplasms, Radiation-Induced/prevention & control , Rats , Reproduction/radiation effects , Risk Assessment , Risk Factors , Sleep Disorders, Circadian Rhythm/epidemiology , Sleep Disorders, Circadian Rhythm/metabolism , Time Factors
9.
Aging (Albany NY) ; 2(2): 82-92, 2010 Mar 20.
Article in English | MEDLINE | ID: mdl-20354269

ABSTRACT

We evaluated the effect of exposure to constant light started at the age of 1 month and at the age of 14 months on the survival, life span, tumorigenesis and age-related dynamics of antioxidant enzymes activity in various organs in comparison to the rats maintained at the standard (12:12 light/dark) light/dark regimen. We found that exposure to constant light started at the age of 1 month accelerated spontaneous tumorigenesis and shortened life span both in male and female rats as compared to the standard regimen. At the same time, the exposure to constant light started at the age of 14 months failed to influence survival of male and female rats. While delaying tumors in males, constant light accelerated tumors in females. We conclude that circadian disruption induced by light-at-night started at the age of 1 month accelerates aging and promotes tumorigenesis in rats, however failed affect survival when started at the age of 14 months.


Subject(s)
Aging/radiation effects , Circadian Rhythm/radiation effects , Light/adverse effects , Neoplasms/etiology , Age Factors , Animals , Catalase/metabolism , Female , Longevity/radiation effects , Male , Oxidative Stress/radiation effects , Photoperiod , Pineal Gland/radiation effects , Rats , Superoxide Dismutase/metabolism
10.
Aging (Albany NY) ; 1(10): 855-65, 2009 Oct 02.
Article in English | MEDLINE | ID: mdl-20157558

ABSTRACT

We evaluated the effect of various light/dark regimens on the survival, life span and tumorigenesis in rats. Two hundred eight male and 203 females LIO rats were subdivided into 4 groups and kept at various light/dark regimens: standard 12:12 light/dark (LD); natural lighting of the North-West of Russia (NL); constant light (LL), and constant darkness (DD) since the age of 25 days until natural death. We found that exposure to NL and LL regimens accelerated development of metabolic syndrome and spontaneous tumorigenesis, shortened life span both in male and females rats as compared to the standard LD regimen. We conclude that circadian disruption induced by light-at-night accelerates aging and promotes tumorigenesis in rats. This observation supports the conclusion of the International Agency Research on Cancer that shift-work that involves circadian disruption is probably carcinogenic to humans.


Subject(s)
Aging, Premature/physiopathology , Aging/physiology , Circadian Rhythm/physiology , Darkness , Light , Neoplasms/physiopathology , Aging/blood , Aging, Premature/blood , Animals , Biomarkers , Blood Glucose/metabolism , Cholesterol/blood , Disease Models, Animal , Female , Homeostasis/physiology , Longevity/physiology , Male , Metabolic Syndrome/physiopathology , Models, Animal , Rats
11.
Biochim Biophys Acta ; 1757(5-6): 573-89, 2006.
Article in English | MEDLINE | ID: mdl-16678784

ABSTRACT

The effect of the pineal indole hormone melatonin on the life span of mice, rats and fruit flies has been studied using various approaches. It has been observed that in female CBA, SHR, SAM and transgenic HER-2/neu mice long-term administration of melatonin was followed by an increase in the mean life span. In rats, melatonin treatment increased survival of male and female rats. In D. melanogaster, supplementation of melatonin to nutrient medium during developmental stages produced contradictory results, but and increase in the longevity of fruit flies has been observed when melatonin was added to food throughout the life span. In mice and rats, melatonin is a potent antioxidant both in vitro and in vivo. Melatonin alone turned out neither toxic nor mutagenic in the Ames test and revealed clastogenic activity at high concentration in the COMET assay. Melatonin has inhibited mutagenesis and clastogenic effect of a number of indirect chemical mutagens. Melatonin inhibits the development of spontaneous and 7-12-dimethlbenz(a)anthracene (DMBA)- or N-nitrosomethylurea-induced mammary carcinogenesis in rodents; colon carcinogenesis induced by 1,2-dimethylhydrazine in rats, N-diethylnitrosamine-induced hepatocarcinogenesis in rats, DMBA-induced carcinogenesis of the uterine cervix and vagina in mice; benzo(a)pyrene-induced soft tissue carcinogenesis and lung carcinogenesis induced by urethan in mice. To identify molecular events regulated by melatonin, gene expression profiles were studied in the heart and brain of melatonin-treated CBA mice using cDNA gene expression arrays (15,247 and 16,897 cDNA clone sets, respectively). It was shown that genes controlling the cell cycle, cell/organism defense, protein expression and transport are the primary effectors for melatonin. Melatonin also increased the expression of some mitochondrial genes (16S, cytochrome c oxidases 1 and 3 (COX1 and COX3), and NADH dehydrogenases 1 and 4 (ND1 and ND4)), which agrees with its ability to inhibit free radical processes. Of great interest is the effect of melatonin upon the expression of a large number of genes related to calcium exchange, such as Cul5, Dcamkl1 and Kcnn4; a significant effect of melatonin on the expression of some oncogenesis-related genes was also detected. Thus, we believe that melatonin may be used for the prevention of premature aging and carcinogenesis.


Subject(s)
Anticarcinogenic Agents/pharmacology , Antimutagenic Agents/pharmacology , Antioxidants/pharmacology , Longevity/drug effects , Melatonin/pharmacology , Neoplasms, Experimental/prevention & control , Animals , Anticarcinogenic Agents/metabolism , Anticarcinogenic Agents/therapeutic use , Antimutagenic Agents/metabolism , Antioxidants/metabolism , Antioxidants/therapeutic use , Cell Line, Tumor , Clinical Trials as Topic , Drosophila , Glucose/metabolism , Humans , Immune System/drug effects , Lipid Metabolism/drug effects , Melatonin/metabolism , Melatonin/therapeutic use , Mice , Neoplasms, Experimental/drug therapy , Rats
12.
Invert Neurosci ; 6(2): 57-68, 2006 Jun.
Article in English | MEDLINE | ID: mdl-16622683

ABSTRACT

The pharynx of Caenorhabditis elegans consists of a syncytium of radially orientated muscle cells that contract synchronously and rhythmically to ingest and crush bacteria and pump them into the intestine of the animal. The action potentials that support this activity are superficially similar to vertebrate cardiac action potentials in appearance with a long, calcium-dependent plateau phase. Although the pharyngeal muscle can generate action potentials in the absence of external calcium ions, action potentials are absent when sodium is removed from the extracellullar solution (Franks et al. 2002). Here we have used whole cell patch clamp recordings from the pharynx and show low voltage-activated inward currents that are present in zero external calcium and reduced in zero external sodium ions. Whilst the lack of effect of zero calcium when sodium ions are present is not surprising in view of the known permeability of voltage-gated calcium channels to sodium ions, the reduction in current in zero sodium when calcium ions are present is harder to explain in terms of a conventional voltage-gated calcium channel. Inward currents were also recorded from egl-19 (n582) which has a loss of function mutation in the pharyngeal L-type calcium channel and these were also markedly reduced in zero external sodium. Despite this apparent dependence on external sodium ions, the current was partially blocked by the divalent cations, cadmium, barium and nickel. Using single-channel recordings we identified a cation channel for which the open-time duration was increased by depolarisation. In inside-out patches, the single-channel conductance was highest in symmetrical sodium solution. Further studies are required to determine the contribution of these channels to the pharyngeal action potential.


Subject(s)
Caenorhabditis elegans Proteins/physiology , Ion Channel Gating/physiology , Ion Channels/physiology , Pharyngeal Muscles/physiology , Animals , Cadmium/pharmacology , Caenorhabditis elegans/physiology , Calcium/pharmacology , Dose-Response Relationship, Radiation , Electric Stimulation/methods , Ion Channel Gating/drug effects , Ion Channel Gating/radiation effects , Ion Channels/classification , Membrane Potentials/physiology , Membrane Potentials/radiation effects , Patch-Clamp Techniques/methods , Pharyngeal Muscles/drug effects , Sodium/pharmacology , Veratridine/pharmacology
13.
J Neurophysiol ; 87(2): 954-61, 2002 Feb.
Article in English | MEDLINE | ID: mdl-11826060

ABSTRACT

The pharynx of C. elegans is a rhythmically active muscle that pumps bacteria into the gut of the nematode. This activity is maintained by action potentials, which qualitatively bear a resemblance to vertebrate cardiac action potentials. Here, the ionic basis of the resting membrane potential and pharyngeal action potential has been characterized using intracellular recording techniques. The resting membrane potential is largely determined by a K(+) permeability, and a ouabain-sensitive, electrogenic pump. As previously suggested, the action potential is at least partly dependent on voltage-gated Ca(2+) channels, as the amplitude was increased as extracellular Ca(2+) was increased, and decreased by L-type Ca(2+) channel blockers verapamil and nifedipine. Barium caused a marked prolongation of action potential duration, suggesting that a calcium-activated K(+) current may contribute to repolarization. Most notably, however, we found that action potentials were abolished in the absence of external Na(+). This may be due, at least in part, to a Na(+)-dependent pacemaker potential. In addition, the persistence of action potentials in nominally free Ca(2+), the inhibition by Na(+) channel blockers procaine and quinidine, and the increase in action potential frequency caused by veratridine, a toxin that alters activation of voltage-gated Na(+) channels, point to the involvement of a voltage-gated Na(+) current. Voltage-clamp analysis is required for detailed characterization of this current, and this is in progress. Nonetheless, these observations are quite surprising in view of the lack of any obvious candidate genes for voltage-gated Na(+) channels in the C. elegans genome. It would therefore be informative to re-evaluate the data from these homology searches, with the aim of identifying the gene(s) conferring this Na(+), quinidine, and veratridine sensitivity to the pharynx.


Subject(s)
Action Potentials/physiology , Caenorhabditis elegans/physiology , Pharyngeal Muscles/physiology , 4-Aminopyridine/pharmacology , Action Potentials/drug effects , Animals , Barium/pharmacology , Calcium/metabolism , Calcium Channel Blockers/pharmacology , Calcium Channels/physiology , Chloride Channels/pharmacology , Chlorides/metabolism , Electrophysiology , Membrane Potentials/drug effects , Membrane Potentials/physiology , Muscarinic Antagonists/pharmacology , Nifedipine/pharmacology , Potassium/metabolism , Potassium Channel Blockers/pharmacology , Potassium Channels/physiology , Quinidine/pharmacology , Sodium/metabolism , Sodium Channels/physiology , Verapamil/pharmacology , Veratridine/pharmacology
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