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1.
Postepy Dermatol Alergol ; 40(3): 402-410, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37545822

ABSTRACT

Introduction: Allergy to nuts, the most common food allergy in childhood, is considered as a significant health problem. Aim: To investigate sensitization to selected nuts in children with or without atopic allergy. Material and methods: Retrospective analysis involved records of 598 children, diagnosed with food allergy. Laboratory data concerned screening for sensitization to major allergens of hazelnut, peanut and walnut. Results: Approximately 77.8% of children with food allergy presented at least one concomitant atopic disease: allergic rhinitis (52.9%), atopic dermatitis (48%) or asthma (31.4%). Nearly one-third experienced at least one episode of anaphylaxis. The nut-specific antibodies were found in 67% of children. Among them, 56% were sensitized to hazelnut, and 54% to peanut. Sensitization to other nuts was less frequent (< 30%). Only 27% of patients were mono-sensitized, the remaining 73% were co-sensitized to two or three of tested nuts. Noteworthy, the occurrence of sensitization varied among age-related groups, and also depended on clinical diagnosis. In patients with sole food allergy the frequency of sensitization was highest in youngest children, whereas, when accompanied by other atopic disease, it was highest in schoolchildren. In children without food allergy, but with another atopic disease, the prevalence of sensitization was relatively low, without any specific pattern. Conclusions: The analysis of sensitization patterns may help to identify patients with an increased risk, and gives the opportunity to introduce more effective prophylaxis. However, since even the first exposure to nuts may be sufficient to trigger the anaphylaxis, this risk should be considered as a serious issue at any age.

2.
Postepy Dermatol Alergol ; 40(1): 40-46, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36909898

ABSTRACT

Introduction: The diagnostics of plant-derived food allergy may be challenging. However, the recognition of sensitization patterns in defined populations, especially in children, is clinically relevant as it enables the use of secondary prophylaxis to prevent life-threatening complications. Aim: To investigate the rates and sensitization patterns to nut allergens in children from central Poland. Material and methods: The retrospective assessment concerned data of 598 children diagnosed in a single centre due to suspected food allergy. The analysis included the results of component-based multiparametric assay Allergy Explorer2 (ALEX2). Results: The sensitization to particular nut allergens varied among patients, depending on their age and nut type. The sensitization to any nut was found in 67% of children, whereas sensitization to hazelnut and peanut was the most common (56% and 55% of all children, respectively). Hazelnut sensitization was predominant in every age, and its prevalence increased with age, while peanut sensitization was detected in more than half of individuals from all groups, except for teenagers (44% of cases). Among hazelnut molecules sensitization to Cor a 1.04 was the most prevalent (74% of sensitized children), and for peanut allergens - Ara h 1 (65% of sensitized patients). The simultaneous sensitization to hazelnut, peanut and walnut (two or all of them) was found in almost half of the entire group. Conclusions: Component-based diagnostics enables differentiation between primary and cross-reactive sensitization to nut allergens and detects co-sensitization. The clinical relevance of the latter observation is remarkable as co-sensitization increases the risk of life-threatening reactions even in trace nut contamination.

3.
Int J Immunopathol Pharmacol ; 36: 20587384211066718, 2022.
Article in English | MEDLINE | ID: mdl-34984934

ABSTRACT

BACKGROUND: Allergy is associated with the loss of tolerance of environmental antigens, combined with a pathological immune response. There were no studies up to date that would show whether the quality of semen decreases in people with allergic diseases. MATERIAL AND METHODS: The research included men who reported to the Gynecological Outpatient Clinic due to reproductive difficulties, defined as the lack of pregnancy after one year of regular intercourse. Semen quality was assessed according to the World Health Organization (WHO) standard. All patients underwent skin prick tests with the most important inhalation allergens (such as hazel, silver birch, mugwort, rye, dog, cat, Dermatophagoides farinae, Dermatophagoides pteronyssinus, alder, Alternaria alternata, Cladosporium herbarum, and grass mix). The data was statistically analyzed. RESULTS: Results of 52 patients aged 25-52 years (34.62 ± 4.96) were analyzed. The mean BMI (Body mass index) was 28.25 (+ -3.77). It was found that 38 men (73%) had increased body weight, and 14 men (26.9%) were obese (BMI > = 30). 13 patients were smokers (25%), and 24 patients (46%) had skin tests positive for at least one inhaled allergen. Sperm tail defects were statistically more significant in patients allergic to birch, rye, cat, alder, and grass. In patients allergic to Alternaria alternata, head defects were statistically more significant (p < .05). No association was found between allergy to house dust mites, mugwort, hazel, and dogs and the deterioration of semen. CONCLUSION: Allergy due to inhalation allergens had an influence on the quality of male semen. Further research is necessary to establish the immunological bases of this phenomenon.


Subject(s)
Allergens/adverse effects , Inhalation Exposure/adverse effects , Spermatozoa/abnormalities , Adult , Alnus , Animals , Betula , Cats , Humans , Hypersensitivity , Infertility, Male , Male , Middle Aged , Poaceae , Secale
4.
Foods ; 10(7)2021 Jul 09.
Article in English | MEDLINE | ID: mdl-34359466

ABSTRACT

The aim of study was to compare the biochemical properties affecting the nutritional quality, safety, and aroma of dry-cured products manufactured from valuable meat of rare native pig breeds: Pulawska (Pul) and Zlotnicka Spotted (ZS). The count of lactic acid bacteria (4.4 log cfu/g) and the release of palmitic (23.1% and 25.9%), oleic (44.1% and 42.2%), and linoleic acids (8.3% and 7.8%), as well as arginine (30.0 and 44.3 mg/kg), histidine (25.8 and 20.6 mg/kg), and lysine (26.8-22.9 mg/kg), shaped the final pH (5.3 and 5.4) in Pul and ZS products during the 4 week maturing, respectively. Lastly, Pul and ZS meat differed in the proportion of decanoic, lauric, stearic, arachidic, and conjugated linoleic acids. The high content of putrescine (23.7 mg/kg), cadaverine (54.3 mg/kg), and tyramine (57.2 mg/kg), as well as a twofold greater share of histamine (163.2 mg/kg) and tryptamine (9.1 mg/kg), indicated a more advanced decarboxylation of ZS meat. Volatile compounds differentiating Pul and ZS meat were primarily hexanal, 3-hydroxybutan-2-one, phenylacetalaldehyde, 2,3-dimethyl-2-cyclopenten-1-one, 2-cyclopenten-1-one, and 3-methyl- and 2-cyclopenten-1-one. Most marked volatile compounds were obtained as a result of microbial activity (acetic acid, 3-methylbutan-1-ol, ethanol, acetone, and 3-hydroxybutan-2-one), advanced lipid oxidation, and decomposition of secondary oxidation products (hexanal, phenylacetaldehyde, and 2-cyclopenten-1-one).

5.
Cancers (Basel) ; 13(9)2021 Apr 24.
Article in English | MEDLINE | ID: mdl-33923337

ABSTRACT

Due to the rarity of high-grade gliomas (HGG) in children, data on this topic are scarce. The study aimed to investigate the long-term results of treatment of children with HGG and to identify factors related to better survival. We performed a retrospective analysis of patients treated for HGG who had the main tumor located outside the brainstem. The evaluation of factors that correlated with better survival was performed with the Cox proportional-hazard model. Survival was estimated with the Kaplan-Meier method. The study group consisted of 82 consecutive patients. All of them underwent surgery as primary treatment. Chemotherapy was applied in 93% of children with one third treated with temozolomide. After or during the systemic treatment, 79% of them received radiotherapy with a median dose of 54 Gy. Median follow-up was 122 months, and during that time, 59 patients died. One-, 2-, 5-, and 10-year overall survival was 78%, 48%, 30% and 17%, respectively. Patients with radical (R0) resection and temozolomide-based chemotherapy had better overall survival. Progression-free survival was better in patients after R0 resection and radical radiotherapy. The best outcome in HGG patients was observed in patients after R0 resection with immediate postoperative temozolomide-based chemotherapy and radical radiotherapy.

6.
Nanoscale ; 13(6): 3686-3697, 2021 Feb 18.
Article in English | MEDLINE | ID: mdl-33543744

ABSTRACT

Amphotericin B (AmB), one of the most powerful but also toxic drugs used to treat systemic mycoses, is believed to selectively permeabilize fungal cell membranes to ions in a sterol-dependent manner. Unfortunately, the structure of the biologically active AmB channels has long eluded researchers, obstructing the design of safer alternatives. Here, we investigate the structural and thermodynamic aspects of channel formation, stability, and selective ion conduction. We combine fluorescence lifetime imaging and molecular simulations to trace the process of channel assembly until the formation of stable, roughly octameric double-length channels (DLCs). This stoichiometry is confirmed by matching the predicted channel conductances with the past results of patch-clamp measurements. We then use free energy calculations to explain the effect of sterols on DLC stability and discuss the observed cation selectivity in structural terms, addressing several long-standing controversies in the context of their physiological relevance. Simulations of ion permeation indicate that only solvated ions pass through DLCs, revealing surprising solvation patterns in the channel lumen. We conclude our investigation by inspecting the role of the tail hydroxyl in the assembly of functional channels, pointing at possible origins of the cholesterol-ergosterol selectivity.


Subject(s)
Amphotericin B , Lipid Bilayers , Amphotericin B/pharmacology , Cell Membrane , Cholesterol , Ergosterol
7.
Comb Chem High Throughput Screen ; 22(6): 370-378, 2019.
Article in English | MEDLINE | ID: mdl-31284855

ABSTRACT

BACKGROUND: Molecular docking has often been used before to calculate in silico affinity of drugs towards their molecular target, but not to estimate leading CYP isoform responsible for metabolism of studied compounds. OBJECTIVE: The aim of this study is to present molecular docking as a valid alternative for costly in vitro studies resulting in estimation of leading CYP isoform. METHODS: In vitro part was based on incubations of studied compounds with isolated CYP3A4 isoform followed by LC-MS analysis. The in silico stage consisted of docking three-dimensional models of the studied compounds with a three-dimensional model of the leading metabolizing isoform (CYP3A4), which was designated during the in vitro part of the study. XenoSite P450 metabolism prediction was also used to predict sites of metabolism and calculate probability values. RESULTS: The calculated affinities showed a clear similarity when the in vitro results were compared with the calculated in silico affinity values. XenoSite CYP3A4 metabolism probability values also confirm significant participation of CYP3A4 in metabolism of studied compounds. CONCLUSION: Both molecular docking and XenoSite P450 metabolism prediction provide data that stands in agreement with in vitro studies, granting a more detailed spectrum on predicting CYP3A4 metabolism, and presenting molecular docking as a promising tool to cut costs and increase effectiveness in early drug development stages.


Subject(s)
Cytochrome P-450 CYP3A/metabolism , Molecular Docking Simulation , Piperazine/metabolism , Cytochrome P-450 CYP3A/chemistry , Humans , Isoenzymes/chemistry , Isoenzymes/metabolism , Models, Molecular , Molecular Structure , Piperazine/chemistry
8.
Pharm Res ; 36(6): 79, 2019 Apr 04.
Article in English | MEDLINE | ID: mdl-30949841

ABSTRACT

PURPOSE: Identification of human insulin analogs' impurity with a mass shift +14 Da in comparison to a parent protein. METHODS: The protein sequence variant was detected and identified with the application of peptide mapping, liquid chromatography, tandem mass spectrometric analysis, nuclear magnetic resonance spectroscopy (NMR) and Edman sequencing. RESULTS: The misincorporated lysine (Lys) at asparagine (Asn) position A21 was detected in recombinant human insulin and its analogs. CONCLUSIONS: Although there are three asparagine residues in the insulin derivative, the misincorporation of lysine occurred only at position A21. The process involves G/U or A/U wobble base pairing.


Subject(s)
Asparagine/chemistry , Escherichia coli/metabolism , Insulins/metabolism , Lysine/analysis , Chromatography, High Pressure Liquid/methods , Escherichia coli/genetics , Humans , Insulins/chemistry , Peptides/chemistry , Recombinant Proteins/chemistry , Recombinant Proteins/metabolism , Tandem Mass Spectrometry/methods
9.
Carbohydr Polym ; 210: 339-349, 2019 Apr 15.
Article in English | MEDLINE | ID: mdl-30732770

ABSTRACT

In this work, two environmentally friendly modification methods, UV irradiation and thermal treatment, were applied for the first time for modifications of oat and barley starches. Their impacts on starch properties were compared with those observed for starch oxidation with NaClO. XRD, EPR, FTIR, SEM and SEC methods were used to characterize the effects of modifications on starch structures. The decreases in molecular weight and crystallinity degree showed the destruction of starch structures upon prolonged UV irradiation and thermal treatment, more advanced in barley starch. The process of radical formation, studied by EPR, occurring to a larger extent in this starch, confirmed lower stability of barley starch structure. The alterations of starch structures correlated well with changes in its functional properties. It was found that UV irradiation was an effective oxidizing agent, whereas heating led mainly to the depolymerization of starch chains.

10.
Biochim Biophys Acta Biomembr ; 1861(1): 93-99, 2019 01.
Article in English | MEDLINE | ID: mdl-30463703

ABSTRACT

Short cationic lipopeptides are amphiphilic molecules that exhibit antimicrobial activity mainly against Gram-positives. These compounds bind to bacterial membranes and disrupt their integrity. Here we examine the structure-activity relation (SAR) of lysine-based lipopeptides, with a prospect to rationally design more active compounds. The presented study aims to explain how antimicrobial activity of lipopeptides is affected by the charge of lipopeptide headgroup and the length of lipopeptide acyl chain. The obtained SAR models suggest that the lipophilicity of short synthetic cationic lipopeptides is the major factor that determines their antimicrobial activities. In order to link the differences in antimicrobial activity to the mechanism of action of lipopeptides containing one and two hydrophobic chains, we additionally performed molecular dynamic (MD) simulations. By using combined coarse-grained and all-atom simulations we also show that these compounds neither affect the organization of the membrane lipids nor aggregate to form separate phases. These results, along with the onset of antimicrobial activity of lipopeptides well below the critical micelle concentration (CMC), indicate that lipopeptides do not act in a simple detergent-like manner.


Subject(s)
Cell Membrane/drug effects , Lipopeptides/chemistry , Molecular Dynamics Simulation , Structure-Activity Relationship , Anti-Bacterial Agents/chemistry , Antimicrobial Cationic Peptides/chemistry , Computer Simulation , Detergents/chemistry , Electrons , Gram-Negative Bacteria/drug effects , Gram-Positive Bacteria/drug effects , Humans , Lipid Bilayers/chemistry , Lysine/chemistry , Membrane Lipids/chemistry , Micelles , Microbial Sensitivity Tests , Serum Albumin, Human/chemistry
11.
Mol Pharm ; 15(9): 4202-4213, 2018 09 04.
Article in English | MEDLINE | ID: mdl-30081640

ABSTRACT

Amphotericin B is a lifesaving polyene antibiotic used in the treatment of systemic mycoses. Unfortunately, the pharmacological applicability of this drug is limited because of its severe toxic side effects. At the same time, the lack of a well-defined mechanism of selectivity hampers the efforts to rationally design safer derivatives. As the drug primarily targets the biomembranes of both fungi and humans, new insights into the binding of amphotericin B to lipid membranes can be helpful in unveiling the molecular mechanisms underlying both its pharmacological activity and toxicity. We use fluorescence-lifetime-imaging microscopy combined with fluorescence-emission spectroscopy in the microscale to study the interaction of amphotericin B with single lipid bilayers, using model systems based on giant unilamellar liposomes formed with three lipids: dipalmitoylphosphatidylcholine (DPPC), dimirystoylphosphatidylcholine (DMPC), and 1-palmitoyl-2-oleoylphosphatidylcholine (POPC). The results show that amphotericin B introduced into the water phase as a DMSO solution binds to the membrane as dimers and small-molecular aggregates that we identify as tetramers and trimers. Fluorescence-detected linear-dichroism measurements revealed high orientational freedom of all the molecular-organization forms with respect to the membrane plane, which suggests that the drug partially binds to the membrane surface. The presence of sterols in the lipid phase (cholesterol but particularly ergosterol at 30 mol %) promotes the penetration of drug molecules into the lipid membrane, as concluded on the basis of the decreased orientation angle of amphotericin B molecules with respect to the axis normal to the membrane plane. Moreover, ergosterol facilitates the association of amphotericin B dimers into aggregated structures that can play a role in membrane destabilization or permeabilization. The presence of cholesterol inhibits the formation of small aggregates in the lipid phase of liposomes, making this system a promising candidate for a low-toxicity antibiotic-delivery system. Our conclusions are supported with molecular simulations that reveal the conformational properties of AmB oligomers in both aqueous solution and lipid bilayers of different compositions.


Subject(s)
Amphotericin B/chemistry , Antifungal Agents/chemistry , 1,2-Dipalmitoylphosphatidylcholine/chemistry , Cholesterol/chemistry , Molecular Dynamics Simulation , Phosphatidylcholines/chemistry
12.
Pharm Res ; 35(7): 143, 2018 May 16.
Article in English | MEDLINE | ID: mdl-29770892

ABSTRACT

PURPOSE: Isolation and identification of unknown impurities of recombinant insulin lispro (produced at IBA) formed during accelerated stability testing of pharmaceutical solutions. For comparative purposes also commercially available formulations of recombinant human insulin (Humulin S®; Lilly), recombinant insulin lispro (Humalog®; Lilly), recombinant insulin aspart (NovoRapid® Penfill®; Novo Nordisk), recombinant insulin detemir (Levemir®; Novo Nordisk) and recombinant insulin glargine (Lantus®; Sanofi-Aventis) were analyzed. METHODS: The impurities of insulin analogs were isolated by RP-HPLC and identified with peptide mass fingerprinting using MALDI-TOF/TOF mass spectrometry. RESULTS: The identified derivatives were N-terminally truncated insulin analog impurities of decreased molecular mass of 119, 147 and 377 Da related to the original protein. The modifications resulting in a mass decrease were detected at the N-terminus of B chains of insulin lispro, insulin aspart, human insulin, insulin glargine, insulin detemir in all tested formulations. To our knowledge it is the first time that these impurities are reported. CONCLUSIONS: The following derivatives formed by truncation of the B chain in insulin analogs were identified in pharmaceutical formulations: desPheB1-N-formyl-ValB2 derivative, desPheB1 derivative, pyroGluB4 derivative.


Subject(s)
Chemistry, Pharmaceutical/methods , Insulin/analogs & derivatives , Insulin/analysis , Drug Compounding/methods , Insulin/chemistry , Peptide Fragments/analysis , Peptide Fragments/chemistry , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methods
13.
Int J Mol Sci ; 19(5)2018 May 16.
Article in English | MEDLINE | ID: mdl-29772699

ABSTRACT

A series of N-(aryl/heteroaryl)-4-(1H-pyrrol-1-yl)benzenesulfonamides were synthesized from 4-amino-N-(aryl/heteroaryl)benzenesulfonamides and 2,5-dimethoxytetrahydrofuran. All the synthesized compounds were evaluated for their anticancer activity on HeLa, HCT-116, and MCF-7 human tumor cell lines. Compound 28, bearing 8-quinolinyl moiety, exhibited the most potent anticancer activity against the HCT-116, MCF-7, and HeLa cell lines, with IC50 values of 3, 5, and 7 µM, respectively. The apoptotic potential of the most active compound (28) was analyzed through various assays: phosphatidylserine translocation, cell cycle distribution, and caspase activation. Compound 28 promoted cell cycle arrest in G2/M phase in cancer cells, induced caspase activity, and increased the population of apoptotic cells. Relationships between structure and biological activity were determined by the QSAR (quantitative structure activity relationships) method. Analysis of quantitative structure activity relationships allowed us to generate OPLS (Orthogonal Projections to Latent Structure) models with verified predictive ability that point out key molecular descriptors influencing benzenosulfonamide's activity.


Subject(s)
Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/pharmacology , Chemistry Techniques, Synthetic , Molecular Structure , Sulfonamides/chemistry , Sulfonamides/pharmacology , Antineoplastic Agents/chemistry , Apoptosis/drug effects , Cell Cycle Checkpoints/drug effects , Cell Line, Tumor , Cell Proliferation/drug effects , Humans , Magnetic Resonance Spectroscopy , Models, Molecular , Molecular Conformation , Quantitative Structure-Activity Relationship , Sulfonamides/chemical synthesis , Benzenesulfonamides
14.
Opt Lett ; 43(4): 643-646, 2018 Feb 15.
Article in English | MEDLINE | ID: mdl-29444042

ABSTRACT

We demonstrate vacuum squeezing at the D1 line of atomic rubidium (795 nm) with a tunable, doubly-resonant, monolithic subthreshold optical parametric oscillator in periodically-poled Rb-doped potassium titanyl phosphate (ppRKTP). The squeezing appears to be undiminished by a strong dispersive optical nonlinearity recently observed in this material.

15.
Wiad Lek ; 71(9): 1854-1859, 2018.
Article in Polish | MEDLINE | ID: mdl-30737953

ABSTRACT

The paper presents the case of an unexplained and the most mysterious death in the history of Polish Tatra tourism. It concerns three people of different ages and occurred on August 3, 1925 in the Valley of Jaworowa. Kazimierz Kasznica, his son Waclaw Kasznica and a newly discovered mountaineer Ryszard Wasserberger died suddenly for unknown reasons in 15 minutes during a mountain trek. This story is interesting due to the mysterious, simultaneous death of three people of different ages and due to the fact that Waleria Kasznica - the wife of Kazimierz and the mother of Waclaw Kasznica survived the journey. KEY WORDS.


Subject(s)
Mountaineering , Fatal Outcome , History, 20th Century , Homicide/history , Humans , Male , Poland
16.
Eur J Med Chem ; 143: 1931-1941, 2018 Jan 01.
Article in English | MEDLINE | ID: mdl-29146134

ABSTRACT

A series of novel 2-(2-arylmethylthio-4-chloro-5-methylbenzenesulfonyl)-1-(6-substituted-4-chloro-1,3,5-triazin-2-ylamino)guanidine derivatives 9-20 have been synthesized by substitution of chlorine atom at the 1,3,5-triazine ring in compounds 5-8 with 3- or 4-aminobenzenesulfonamide and 4-(aminomethyl)benzenesulfonamide hydrochloride. All the synthesized compounds were evaluated for their inhibitory activity toward hCA I, II, IX and XII as well as anticancer activity against HeLa, HCT-116 and MCF-7 human tumor cell lines. The investigated compounds showed weak inhibitory potency against the human CA I, while activity toward hCA II was differentiated and depended on structure of inhibitor (KI: 5.4-933.1 nM). Compounds containing the 4-sulfamoylphenyl moiety (9-12) exhibited the strongest inhibitory activity against hCA IX with KI values from 37.1 to 42.9 nM, as well as against hCA XII in range of 31-91.9 nM. The most promising compound 12 (KI = 41 nM) showed the highest selectivity toward hCA IX versus hCA I (hCA I/hCA IX = 18) and hCA II (hCA II/hCA IX = 4). Compound 12 displayed prominent cytotoxic effect selectively toward HeLa cancer cells (IC50 = 17 µM) and did not exhibit toxicity to the non-cancerous HaCaT cells. In silico analysis suggested that despite the lack of a single binding pose, the selective affinity is conferred by specific interactions with an arginine moiety, as well as better-defined binding modes within the active site.


Subject(s)
Antineoplastic Agents/pharmacology , Carbonic Anhydrase Inhibitors/pharmacology , Guanidine/pharmacology , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Carbonic Anhydrase I/antagonists & inhibitors , Carbonic Anhydrase I/metabolism , Carbonic Anhydrase II/antagonists & inhibitors , Carbonic Anhydrase II/metabolism , Carbonic Anhydrase IX/antagonists & inhibitors , Carbonic Anhydrase IX/metabolism , Carbonic Anhydrase Inhibitors/chemical synthesis , Carbonic Anhydrase Inhibitors/chemistry , Carbonic Anhydrases/metabolism , Cell Proliferation/drug effects , Cell Survival/drug effects , Dose-Response Relationship, Drug , Drug Screening Assays, Antitumor , Guanidine/analogs & derivatives , Guanidine/chemistry , Humans , Isoenzymes/antagonists & inhibitors , Isoenzymes/metabolism , Models, Molecular , Molecular Structure , Structure-Activity Relationship , Tumor Cells, Cultured
17.
Opt Lett ; 42(24): 5298-5301, 2017 Dec 15.
Article in English | MEDLINE | ID: mdl-29240197

ABSTRACT

We demonstrate a nonlinear optical resonator that tunes itself onto resonance with an input beam. In a monolithic Fabry-Perot cavity implemented in rubidium-doped periodically poled potassium titanyl phosphate, an intensity-dependent refractive index produces line pulling by multiple free-spectral ranges (FSRs). In this condition, the cavity passively maintains optical resonance in the face of FSR-scale excursions of the drive laser frequency: when one resonant operating point becomes unstable, the resonator rapidly transitions to another resonant operating point. We demonstrate stable second-harmonic generation with no active feedback to the laser or cavity. The self-tuning effect appears to be supported by a very strong, previously unreported optical nonlinearity.

18.
Eur J Med Chem ; 138: 357-370, 2017 Sep 29.
Article in English | MEDLINE | ID: mdl-28688276

ABSTRACT

A series of new 2-(2-alkylthiobenzenesulfonyl)-3-(phenylprop-2-ynylideneamino)guanidine derivatives have been synthesized and evaluated in vitro by MTT assays for their antiproliferative activity against cell lines of colon cancer HCT-116, cervical cancer HeLa and breast cancer MCF-7. The obtained results indicated that these compounds display prominent cytotoxic effect. The best anticancer properties have been observed for derivatives 44 (IC50 = 6-18 µM) and 45 (IC50 = 8-14 µM). Very good results of antiproliferative assays have been also shown for compounds 26, 36, and 46 and noticeable anticancer profile has been found for set of derivatives 34-39. Based on results of MTT assays the structure-activity relationships have been drawn. More in-depth biological research revealed that compounds 26, 33, 37, 39, 41 and 43 display cytotoxic effect only against cancer cells and do not inhibit the growth of non-malignant HaCaT cells. Furthermore, the novel series of derivatives have shown good metabolic stability, especially among the pharmacologically active compounds. To obtain a deeper insight into the molecular description of compounds activity the QSAR studies have been applied. Support vector machines (SVM) have been used to developed QSAR models for predicting the anti-proliferative activity of novel derivatives. The obtained SVM models have shown prognostic ability for HCT-116 and HeLa cell lines and as a result these models may be useful for further development of structurally similar derivatives with better biological properties.


Subject(s)
Antineoplastic Agents/pharmacology , Guanidine/pharmacology , Quantitative Structure-Activity Relationship , Antineoplastic Agents/chemistry , Antineoplastic Agents/metabolism , Cell Proliferation/drug effects , Cell Survival/drug effects , Dose-Response Relationship, Drug , Drug Screening Assays, Antitumor , Guanidine/analogs & derivatives , Guanidine/chemistry , Humans , Molecular Conformation , Tumor Cells, Cultured
19.
Opt Express ; 25(2): 1142-1150, 2017 Jan 23.
Article in English | MEDLINE | ID: mdl-28157999

ABSTRACT

We demonstrate a monolithic frequency converter incorporating up to four tuning degrees of freedom, three temperature and one strain, allowing resonance of pump and generated wavelengths simultaneous with optimal phase-matching. With a Rb-doped periodically-poled potassium titanyl phosphate (KTP) implementation, we demonstrate efficient continuous-wave second harmonic generation from 795 to 397, with low-power efficiency of 72% and high-power slope efficiency of 4.5%. The measured performance shows good agreement with theoretical modeling of the device. We measure optical bistability effects, and show how they can be used to improve the stability of the output against pump frequency and amplitude variations.

20.
Chem Biol Drug Des ; 90(3): 380-396, 2017 Sep.
Article in English | MEDLINE | ID: mdl-28122174

ABSTRACT

A series of novel 2-alkylthio-4-chloro-N-(5-oxo-4,5-dihydro-1,2,4-triazin-3-yl)benzenesulfonamide derivatives 12-46 have been synthesized by the reaction of aminoguanidines with an appropriate alpha-oxo-acids hydrates in glacial acetic acid. All the synthesized compounds were evaluated for their anticancer activity against HeLa, HCT-116, and MCF-7 human tumor cell lines. Two compounds 33 and 34 displayed outstanding cytotoxic effect selectively toward HeLa cancer cells (IC50  = 19 µm) and did not exhibit toxicity to the non-cancerous HaCaT cells. QSAR analysis determined the most important parameters controlling cytotoxic activity of 5-oxo-1,2,4-triazines against HeLa cells. QSAR model showed five significant descriptors: HATS6s (GETAWAY descriptor), RDF125 m (radial distribution function), SpMax7_Bh(p) (Burden descriptor), SM3_G (3D matrix descriptor), and Hy (hydrophilic factor). The apoptotic potential of the most active compounds was thoroughly analyzed through various assays: cells' morphology, DNA fragmentation, mitochondrial potential disruption, and phosphatidylserine translocation. Selected compounds were tested for metabolic stability in the presence of pooled human liver microsomes and NADPH. Compound 34 was the most resistant for human metabolism (t1/2  = 38.5 min) and can be pointed as a hit compound for further investigations.


Subject(s)
Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Quantitative Structure-Activity Relationship , Sulfonamides/chemical synthesis , Sulfonamides/pharmacology , Cell Cycle Checkpoints/drug effects , DNA Fragmentation/drug effects , Drug Design , Drug Screening Assays, Antitumor , HCT116 Cells , HeLa Cells , Humans , MCF-7 Cells , Membrane Potential, Mitochondrial/drug effects , Sulfonamides/chemistry , Triazines/chemistry , Benzenesulfonamides
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