Search results for "ACID"
showing 10 items of 13107 documents
Investigations on the Steroidal Anti-Inflammatory Activity of Triterpenoids fromDiospyros leucomelas*
1995
Three triterpenes were isolated from Diospyros leucomelas and identified as betulin, betulinic acid, and ursolic acid. They showed anti-inflammatory activity in the carrageenan and serotonin paw edema tests and TPA and EPP ear edema tests. The blockade of their effects by progesterone, actinomycin D, and cycloheximide has served to determine the mechanism of action in relationship with that of glucocorticoids. Betulinic acid was the most affected and therefore a mode of action similar to these drugs may be postulated for it.
Modular Solid-Phase Synthesis of Antiprotozoal Barnesin Derivatives
2020
Here, we applied and optimized a solid support (SP)-based Horner-Wadsworth-Emmons reagent to prepare SP-bound vinylogous amino acids. Subsequent SP-based peptide synthesis, global deprotection, and chemical modifications yielded 14 lipodipeptides carrying vinylogous amino acids, including the natural product barnesin A (1). Biological evaluation revealed that several synthesized derivatives show micromolar to nanomolar inhibitory activity against papain-like cysteine proteases, human cathepsin L, and rhodesain.
Anti-phospholipase A2 and anti-inflammatory activity of Santolina chamaecyparissus
2000
The activity of the Santolina chamaecyparissus methanol extract was tested against the phospholipase A2 (PLA2)-induced mouse paw edema and in vitro inhibition of PLA2 activity. After fractionation, only the dichloromethane extract was active against the PLA2 in vitro test. In addition, it reduced the edema induced by arachidonic acid, and by 12-O-tetradecanoylphorbol-13-acetate in a multidose test. After chromatography on silicagel and gel filtration on Sephadex, and using an in vitro anti-PLA2 assay-guided process, we have isolated and identified from the dichloromethane extract the flavone nepetin and four sesquiterpenes.
Squaric Acid-Based Radiopharmaceuticals for Tumor Imaging and Therapy.
2021
Targeting vectors bound to a chelator represent a significant fraction of radiopharmaceuticals used nowadays for diagnostic and therapeutic purposes in nuclear medicine. The use of squaramides as coupling units for chelator and targeting vector helps to circumvent the disadvantages of several common coupling methods. This review gives an overview of the use of squaric acid diesters (SADE) as linking agents. It focuses on the conjugation of cyclic chelators, e.g., DOTA (1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid), as well as hybrid chelators like AAZTA5 (6-pentanoic acid-6-amino-1,4-diazepine tetracetic acid) or DATA5m (6-pentanoic acid-6-amino-1,4-diazapine-triacetate) to diff…
Identification and characterization of a monoclonal antibody to the membrane fatty acid binding protein
1992
A monoclonal antibody to the rat liver membrane fatty acid binding protein (MFABP) was prepared by immunizing mice with purified MFABP isolated from solubilized rat liver plasma membrane proteins by oleate-agarose affinity chromatography technique. The monoclonal antibody K15/6 identified a single 40 kDa protein in rat liver plasma membranes with pI values of 8.5, 8.8 and 9.0, which is identical to the authentic MFABP, but clearly distinct from rat mitochondrial GOT. The antibody K15/6 selectively inhibited cellular influx as well as membrane binding of fatty acids, but not of cholesterol or vitamin E. The same antibody was used in immunofluorescence, ELISA and Western blot analysis to dete…
Theoretical prediction of the photoinduced chemiluminescence of pesticides
2007
Although it is relatively easy to find chemiluminescent (CL) molecules working on the field of direct liquid phase (especially employing strong oxidants), the molecules found as chemiluminescent are normally very weak CL compounds for developing suitable analytical CL-procedures. Therefore, it is mandatory to develop new strategies to enhance in a simple way the native chemiluminescence of such a compounds, and even to increase the number of compounds to be determined by direct chemiluminescence. Photoinduced chemiluminescence (Ph-CL) results in a simple and easily on-line accessible strategy to solve these disadvantages. In the present paper, molecular connectivity, a topological method wh…
Cytotoxic effects of Jay Amin hydroxamic acid (JAHA), a ferrocene-based class I histone deacetylase inhibitor, on triple-negative MDA-MB231 breast ca…
2012
The histone deacetylase inhibitors (HDACis) are a class of chemically heterogeneous anticancer agents of which suberoylanilide hydroxamic acid (SAHA) is a prototypical member. SAHA derivatives may be obtained by three-dimensional manipulation of SAHA aryl cap, such as the incorporation of a ferrocene unit like that present in Jay Amin hydroxamic acid (JAHA) and homo-JAHA [ Spencer , et al. ( 2011 ) ACS Med. Chem. Lett. 2 , 358 - 362 ]. These metal-based SAHA analogues have been tested for their cytotoxic activity toward triple-negative MDA-MB231 breast cancer cells. The results obtained indicate that of the two compounds tested, only JAHA was prominently active on breast cancer cells with a…
Geranylgeranyl as well as farnesyl moiety is transferred to Ras p21 overproduced in adrenocortical cells transformed by c-Ha-rasEJ oncogene.
1997
The ras-transformed newborn rat adrenocortical (RTAC) cells were obtained by transfection with the mutated c-Ha-rasEJ oncogene. They are proliferative and tumorigenic cells characterized by expression of the c-Ha-rasEJ oncogene and overexpression of a wild-type ras oncogene. The overproduced Ras p21 was identified here as Ki-Ras p21 by western blotting using a specific anti-Ki-Ras monoclonal antibody. Radioactivity derived from [14C]mevalonolactone was strongly incorporated into Ras p21 overproduced in RTAC cells. RTAC cells pretreated with lovastatin and labeled with either [3H]geranylgeranyl-pyrophosphate or [3H]farnesyl-pyrophosphate incorporated also radioactivity into Ras p21. These re…
Synthesis of nucleoside and nucleotide conjugates of bile acids, and polymerase construction of bile acid-functionalized DNA.
2010
Aqueous Sonogashira cross-coupling reactions of 5-iodopyrimidine or 7-iodo-7-deazaadenine nucleosides with bile acid-derived terminal acetylenes linked via an ester or amide tether gave the corresponding bile acid–nucleoside conjugates. Analogous reactions of halogenated nucleoside triphosphates gave directly bile acid-modified dNTPs. Enzymatic incorporation of these modified nucleotides to DNA was successfully performed using Phusion polymerase for primer extension. One of the dNTPs (dCTP bearing cholic acid) was also efficient for PCR amplification.
The C-terminal antibody binding domain ofCandida albicansmp58 represents a protective epitope during candidiasis
2003
The 58-kDa surface mannoprotein of Candida albicans (mp58) elicits strong antibody responses during infection. Epitope mapping with sera from patients with candidiasis and control individuals indicated the presence of multiple IgG-reactive continuous epitopes on the protein, expanding both the amino- and carboxy-terminal domains and several internal regions. These immunoreactive regions were similar to the ones previously identified using sera from immunized animals. Two of the epitopic regions (including the C-terminal domain) showed increased reactivity with antibodies present in sera from patients with candidiasis as compared to control individuals. Patients who survived the infection di…