Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 90
Filter
1.
Appl Biochem Biotechnol ; 196(1): 417-435, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37140782

ABSTRACT

Dehydroandrographolide (DA) was isolated and experimentally characterized utilizing FT-IR, UV-Vis, and NMR spectroscopy techniques along with detailed theoretical modelled at the DFT/B3LYP-D3BJ/6-311 + + G(d,p) level of theory. Substantially, molecular electronic property investigations in the gaseous phase alongside five different solvents (ethanol, methanol, water, acetonitrile and DMSO) were comprehensively reported and compared with the experimental results. The globally harmonized scale (GHS), which is used to identify and label chemicals, was also utilized to demonstrate that the lead compound predicted an LD50 of 1190 mg/kg. This finding implies that consumers can safely consume the lead molecule. Notable impacts on hepatotoxicity, cytotoxicity, mutagenicity, and carcinogenicity were likewise found to be minimal to nonexistent for the compound. Additionally, in order to account for the biological performance of the studied compound, in-silico molecular docking simulation analysis was examined against different anti-inflammatory target of enzymes (3PGH, 4COX, and 6COX). From the examination, it can be inferred that DA@3PGH, DA@4COX, and DA@6COX, respectively, showed significant negative binding affinities of -7.2 kcal/mol, -8.0 kcal/mol, and - 6.9 kcal/mol. Thus, the high mean binding affinity in contrast to conventional drugs further reinforces these results as an anti-inflammatory agent.


Subject(s)
Anti-Inflammatory Agents , Diterpenes , Spectrum Analysis, Raman , Molecular Docking Simulation , Spectroscopy, Fourier Transform Infrared , Magnetic Resonance Spectroscopy , Anti-Inflammatory Agents/pharmacology , Spectrophotometry, Ultraviolet
2.
ACS Omega ; 7(50): 46183-46202, 2022 Dec 20.
Article in English | MEDLINE | ID: mdl-36570229

ABSTRACT

This study focused on the potential of aluminum nitride (Al12N12) and aluminum phosphide (Al12P12) nanomaterials as anode electrodes of lithium-ion (Li-ion), sodium-ion (Na-ion), and potassium-ion (K-ion) batteries as investigated via density functional theory (DFT) calculations at PBE0-D3, M062X-D3, and DSDPBEP86 as the reference method. The results show that the Li-ion battery has a higher cell voltage with a binding energy of -1.210 eV and higher reduction potential of -6.791 kcal/mol compared to the sodium and potassium ion batteries with binding energies of -0.749 and -0.935 eV and reduction potentials of -6.414 and -6.513 kcal/mol, respectively, using Al12N12 material. However, in Al12P12, increases in the binding energy and reduction potential were observed in the K-ion battery with values -1.485 eV and -7.535 kcal/mol higher than the Li and Na ion batteries with binding energy and reduction potential -1.483, -1.311 eV and -7.071, -7.184 eV, respectively. Finally, Al12N12 and Al12P12 were both proposed as novel anode electrodes in Li-ion and K-ion batteries with the highest performances.

3.
Cell Immunol ; 212(1): 44-50, 2001 Aug 25.
Article in English | MEDLINE | ID: mdl-11716528

ABSTRACT

Previous studies provide evidence for in vivo activation of MBP-reactive T cells in subjects with multiple sclerosis. In general, in vivo activation occurs less frequently in healthy control subjects. In the current study we examined the T cell response to proteolipid protein in PBMC isolated from 9 control subjects. We used CD45 isotypes as markers for memory and naïve T cells to assess in vivo activation of CD4+ T cells reactive with PLP. In contrast to the results obtained using MBP, we found that approximately 50% of PLP-reactive T cells were derived from the CD45RO+ memory subpopulation of T cells isolated from these control subjects. These results indicate that some myelin-reactive T cells have undergone activation in vivo in neurologically intact individuals. This suggests that immunoregulatory mechanisms may be present that prevent overt disease in spite of in vivo activation of PLP-reactive T cells.


Subject(s)
Immunologic Memory , Leukocyte Common Antigens/immunology , Myelin Proteolipid Protein/immunology , T-Lymphocyte Subsets/immunology , Adult , Autoimmunity , Female , Humans , Lymphocyte Activation/immunology , Male , Myelin Basic Protein/immunology , Reference Values
6.
J Biol Chem ; 276(16): 12636-44, 2001 Apr 20.
Article in English | MEDLINE | ID: mdl-11304548

ABSTRACT

Interactions of the yeast chromatin-remodeling complexes SWI/SNF and RSC with nucleosomes were probed using site-specific DNA photoaffinity labeling. 5 S rDNA was engineered with photoreactive nucleotides incorporated at different sites in DNA to scan for the subunits of SWI/SNF in close proximity to DNA when SWI/SNF is bound to the 5 S nucleosome or to the free 5 S rDNA. The Swi2/Snf2 and Snf6 subunits of SWI/SNF were efficiently cross-linked at several positions in the nucleosome, whereas only Snf6 was efficiently cross-linked when SWI/SNF was bound to free DNA. DNA photoaffinity labeling of RSC showed that the Rsc4 subunit is in close proximity to nucleosomal DNA and not when RSC is bound to free DNA. After remodeling, the Swi2/Snf2 and Rsc4 subunits are no longer detected near the nucleosomal DNA and are evidently displaced from the surface of the nucleosome, indicating significant changes in SWI/SNF and RSC contacts with DNA after remodeling.


Subject(s)
Chromatin/physiology , DNA, Ribosomal/metabolism , DNA-Binding Proteins/metabolism , Nucleosomes/physiology , Saccharomyces cerevisiae Proteins , Saccharomyces cerevisiae/physiology , Transcription Factors/metabolism , Adenosine Triphosphate/analogs & derivatives , Adenosine Triphosphate/metabolism , Affinity Labels , Base Sequence , Binding Sites , Chromatin/ultrastructure , Chromosomal Proteins, Non-Histone , DNA, Fungal/chemistry , DNA, Fungal/genetics , DNA, Fungal/metabolism , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Fungal Proteins/metabolism , Molecular Sequence Data , Nuclear Proteins/metabolism , RNA, Ribosomal, 5S/genetics , Restriction Mapping , Saccharomyces cerevisiae/genetics
7.
Biochem Syst Ecol ; 29(1): 105-107, 2001 Jan 01.
Article in English | MEDLINE | ID: mdl-11068127
8.
Biochem Syst Ecol ; 29(1): 109-111, 2001 Jan 01.
Article in English | MEDLINE | ID: mdl-11068128
9.
12.
Nucleic Acids Res ; 28(21): 4382-90, 2000 Nov 01.
Article in English | MEDLINE | ID: mdl-11058139

ABSTRACT

Two new photoreactive dATP analogs, N(6)-[4-azidobenzoyl-(2-aminoethyl)]-2'-deoxyadenosine-5'-triphospha+ ++ te (AB-dATP) and N(6)-[4-[3-(trifluoromethyl)-diazirin-3-yl]benzoyl-(2-aminoethyl) ]-2 '-deoxyadenosine-5'-triphosphate (DB-dATP), were synthesized from 2'-deoxyadenosine-5'-monophosphate in a six step procedure. Synthesis starts with aminoethylation of dAMP and continues with rearrangement of N(1)-(2-aminoethyl)-2'-deoxyadenosine-5'-monophosphate to N(6)-(2-aminoethyl)-2'-deoxyadenosine-5'-monophosphate (N(6)-dAMP). Next, N(6)-dAMP is converted into the triphosphate form by first protecting the N-6 primary amino group before coupling the pyrophosphate. After pyrophosphorylation, the material is deprotected to yield N(6)-(2-aminoethyl)-2'-deoxyadenosine-5'-triphosphate (N(6)-dATP). The N-6 amino group is subsequently used to attach either a phenylazide or phenyldiazirine and the photoreactive nucleotide is then enzymatically incorporated into DNA. N(6)-dATP and its photoreactive analogs AB-dATP and DB-dATP were successfully incorporated into DNA using the exonuclease-free Klenow fragment of DNA polymerase I in a primer extension reaction. UV irradiation of the primer extension reaction with AB-dATP or DB-dATP showed specific photocrosslinking of DNA polymerase I to DNA.


Subject(s)
DNA/metabolism , Deoxyadenine Nucleotides/chemistry , Deoxyadenine Nucleotides/metabolism , Photoaffinity Labels/chemistry , Photoaffinity Labels/metabolism , Adenine/chemistry , Adenine/metabolism , Adenosine Monophosphate/analogs & derivatives , Adenosine Monophosphate/chemistry , Adenosine Monophosphate/metabolism , Azides/chemistry , Azides/metabolism , Base Sequence , Chromatography, Thin Layer , DNA/chemistry , DNA/genetics , DNA Polymerase I/metabolism , DNA-Binding Proteins/metabolism , Deoxyadenine Nucleotides/chemical synthesis , Deoxyadenosines/chemistry , Deoxyadenosines/metabolism , Diphosphates/metabolism , Indicators and Reagents/chemistry , Indicators and Reagents/metabolism , Phosphorylation , Photoaffinity Labels/chemical synthesis
13.
Eur J Immunol ; 30(7): 1894-901, 2000 Jul.
Article in English | MEDLINE | ID: mdl-10940878

ABSTRACT

There is a reduction in the average telomere lengths of CD4+ "memory" T cells, defined by the CD45RO+ phenotype, compared to CD54RA+ "naive" T cells. However, other studies suggest that telomerase activity often is sufficient to maintain the telomere length of certain B and T cell populations following immune activation in vivo. Thus it is uncertain whether genuine memory CD4+ T cells, defined by an immune response to specific recall antigens, would display telomeres of reduced length, or whether telomere size would be maintained. Therefore, we examined the telomere lengths of T cells responding to two common recall antigens, tetanus toxoid and Candida albicans. Telomere terminal restriction fragment length was assessed by Southern blots or by flow cytometry following in situ hybridization with telomere-specific peptide nucleic acid probes. For the five subjects tested, the Candida- or tetanus-reactive memory T cell populations demonstrated a significant reduction of telomere length even when compared to the phenotypically defined memory CD45RO+ T cell populations isolated from peripheral blood mononuclear cells. This finding suggests that telomerase activity does not fully compensate for the effects of in vivo activation and proliferation of some antigen-specific CD4+ T cell populations. This may contribute to immune senescence.


Subject(s)
CD4-Positive T-Lymphocytes/immunology , Immunologic Memory/immunology , Telomere , Adult , CD4-Positive T-Lymphocytes/cytology , Candida albicans/immunology , Cells, Cultured , Flow Cytometry/methods , Humans , In Situ Hybridization/methods , Leukocyte Common Antigens/immunology , Middle Aged , Tetanus Toxoid/immunology
15.
Fitoterapia ; 71(3): 328-30, 2000 Jun.
Article in English | MEDLINE | ID: mdl-10844174

ABSTRACT

High performance liquid chromatographic (HPLC) analysis of a dichloromethane extract of the stem-barks of Balanites aegyptiaca has yielded two known alkaloids, N-trans-feruloyltyramine (1) and N-cis-feruloyltyramine (2), and three common metabolites, vanillic acid, syringic acid and 3-hydroxy-1-(4-hydroxy-3-methoxyphenyl)-1-propanone.


Subject(s)
Alkaloids/chemistry , Coumaric Acids/chemistry , Plant Extracts/chemistry , Plants, Medicinal , Tyramine/chemistry , Chromatography, High Pressure Liquid , Humans , Tyramine/analogs & derivatives
16.
17.
Fitoterapia ; 71(5): 580-3, 2000 Sep.
Article in English | MEDLINE | ID: mdl-11449514

ABSTRACT

Calendin (1), cinnamic acid (2), 3-hydroxy-1-(4-hydroxy-3-methoxyphenyl)-propan-1-one (3), 2,3-dihydroxy-1-(4-hydroxy-3-methoxyphenyl)-propan-1-one (4), 3-hydroxy-1-(4-hydroxy-3,5-dimethoxyphenyl)-propan-1-one (5), syringic acid (6) and vanillic acid (7) have been isolated from a dichloromethane extract of the leaves and branches of Cassia laevigata.


Subject(s)
Lactones/isolation & purification , Phenols/isolation & purification , Plants, Medicinal , Rosales , Humans , Lactones/chemistry , Phenols/chemistry , Plant Extracts/chemistry , Plant Extracts/isolation & purification , Plant Leaves
18.
Fitoterapia ; 71(5): 595-7, 2000 Sep.
Article in English | MEDLINE | ID: mdl-11449519

ABSTRACT

Reversed-phase HPLC analysis of a dichloromethane extract of the stem-barks of Rinorea welwitschii has afforded two pyranoisoflavones, alpinumisoflavone (1) and di-O-methylalpinumisoflavone (2).


Subject(s)
Flavonoids/isolation & purification , Isoflavones , Plants, Medicinal , Rosales , Chromatography, High Pressure Liquid , Flavonoids/chemistry , Humans , Plant Extracts/chemistry , Plant Extracts/isolation & purification , Plant Stems
19.
Methods ; 19(3): 434-46, 1999 Nov.
Article in English | MEDLINE | ID: mdl-10579939

ABSTRACT

The ability of large protein assemblies to reorganize chromatin in an ATP-dependent manner is an important process for regulation of gene expression and potentially for DNA replication and recombination. The manner in which these proteins remodel chromatin to make the DNA accessible to DNA binding proteins such as transcription factors is not well understood. Site-directed DNA-protein cross-linking has been used to understand the architecture of the SWI/SNF-nucleosomal complex and the mechanistic details of how the nucleosome is remodeled. A detailed protocol for such a study is presented along with examples of the extent of this approach.


Subject(s)
DNA/chemistry , Molecular Biology/methods , Nucleosomes/chemistry , Photochemistry/methods , Base Sequence , Cross-Linking Reagents , DNA/metabolism , Molecular Sequence Data , Nucleosomes/metabolism
20.
J Biol Chem ; 274(43): 30510-9, 1999 Oct 22.
Article in English | MEDLINE | ID: mdl-10521432

ABSTRACT

Nuclear DEAF-1-related (NUDR) protein is a novel transcriptional regulator with sequence similarity to developmental and oncogenic proteins. NUDR protein deletions were used to localize the DNA binding domain between amino acids 167 and 368, and site-specific DNA photocross-linking indicated at least two sites of protein-DNA contact within this domain. The DNA binding domain contains a proline-rich region and a region with similarity to a Myc-type helix-loop-helix domain but does not include the zinc finger motif at the C terminus. Deoxyribonuclease I protection assays confirmed the presence of multiple NUDR binding motifs (TTC(C/G)G) in the heterogeneous nuclear ribonucleoprotein A2/B1 (hnRNP A2/B1) promoter and also in the 5'-untranslated region (UTR) of hNUDR cDNA. NUDR produced a 65-70% repression of the hnRNP A2/B1 promoter activity, and NUDR binding motifs in the 5'-UTR were found to mediate this repression. NUDR-dependent repression was also observed when the 5'-UTR of NUDR was placed onto a heterologous thymidine kinase promoter in an analogous 5'-UTR position but not when placed upstream of transcription initiation. These results suggest that NUDR may regulate the in vivo expression of hnRNP A2/B1 and NUDR genes and imply that inactivation of NUDR could contribute to the overexpression of hnRNP A2/B1 observed in some human cancers.


Subject(s)
DNA-Binding Proteins/genetics , Nuclear Proteins/metabolism , Promoter Regions, Genetic , Transcription, Genetic , 5' Untranslated Regions/genetics , Base Sequence , Binding Sites , DNA-Binding Proteins/metabolism , Gene Expression Regulation , Helix-Loop-Helix Motifs , Heterogeneous-Nuclear Ribonucleoprotein Group A-B , Humans , Molecular Sequence Data , Neoplasms/genetics , Nuclear Proteins/genetics , Proline , Repressor Proteins/chemistry , Repressor Proteins/metabolism , Thymidine Kinase/genetics , Transcription Factors
SELECTION OF CITATIONS
SEARCH DETAIL