In this study, we pioneered an alternative technology for manufacturing subunit influenza hemagglutinin (HA)-based vaccines. This innovative method involves harnessing the pupae of the Lepidoptera () as natural biofactories in combination with baculovirus vectors (using CrisBio technology). We engineered recombinant baculoviruses encoding two versions of the HA protein (trimeric or monomeric) derived from a pandemic avian H7N1 virus A strain (A/chicken/Italy/5093/99).
View Article and Find Full Text PDFThe VP60 capsid protein from rabbit haemorrhagic disease virus (RHDV), the causative agent of one of the most economically important disease in rabbits worldwide, forms virus-like particles (VLPs) when expressed using heterologous protein expression systems such as recombinant baculovirus, yeasts, plants or mammalian cell cultures. To prevent RHDV dissemination, it would be beneficial to develop a bivalent vaccine including both RHDV GI.1- and RHDV GI.
View Article and Find Full Text PDFVaccines based on virus-like particles (VLPs) have proven effective in humans and animals. In this regard, the baculovirus expression vector system (BEVS) is one of the technologies of choice to generate such highly immunogenic vaccines. The extended use of these vaccines for human and animal populations is constrained because of high production costs, therefore a significant improvement in productivity is crucial to ensure their commercial viability.
View Article and Find Full Text PDFParasitic diseases plague billions of people among the poorest, killing millions annually, and causing additional millions of disability-adjusted life years lost. Leishmaniases affect more than 12 million people, with over 350 million people at risk. There is an urgent need for efficacious and cheap vaccines and treatments against visceral leishmaniasis (VL), its most severe form.
View Article and Find Full Text PDFA molecular library of quaternary ammonium salts (QASs), mainly composed of symmetrical bis-quaternary heterocyclic bromides exhibiting choline kinase (ChoK) inhibitory activity, were evaluated for their ability to inhibit acetyl- and butyrylcholinesterase (AChE and BChE, respectively). The molecular framework of QASs consisted of two positively charged heteroaromatic (pyridinium or quinolinium) or sterically hindered aliphatic (quinuclidinium) nitrogen rings kept at an appropriate distance by lipophilic rigid or semirigid linkers. Many homodimeric QASs showed AChE and BChE inhibitory potency in the nanomolar range along with a low enzymatic selectivity.
View Article and Find Full Text PDFLeishmania infantum causes visceral leishmaniasis, a severe zoonotic and systemic disease that is fatal if left untreated. Identification of the antigens involved in Leishmania-specific protective immune response is a research priority for the development of effective control measures. For this purpose, we evaluated, in 27 dogs from an enzootic zone, specific humoral and cellular immune response by delayed-type hypersensitivity (DTH) skin test both against total L.
View Article and Find Full Text PDFBackground: (RS)-1-{[3-(2-Hydroxyethoxy)-1-isopropoxy]propyl}-5-fluorouracil proved to be a good differentiating agent against rhabdomyosarcoma cells.
Objective: As lipophilicity is known to affect the anticancer activity, the synthesis of a wide range of 5-fluorouracil derivatives linked to benzo-fused seven-membered rings was undertaken.
Methods: The decision was then made to change 5-fluorouracil for uracil, with the prospect of finding an antiproliferative agent endowed with a new mechanism of action.
Mycobacterial species are able to control rRNA production through variations in the number and strength of promoters controlling their rrn operons. Mycobacterium chelonae and M. fortuitum are members of the rapidly growing mycobacterial group.
View Article and Find Full Text PDFWe have synthesized and evaluated a series of hybrids of polypyrrole minor groove binders structurally related to the natural antitumor agent distamycin A, and alpha-methylene-gamma-butyrolactones with methyl, phenyl, and 4-substituted phenyl groups at the lactone C(gamma) position, denoted 5-17, for in vitro cytotoxic activity against a variety of cancer cell lines. The apoptotic and cytotoxic activities against several tumor cell lines are reported and discussed in terms of their structural differences in relation to both the number of N-methylpyrrole rings and the type of the alkylating unit tethered to the oligopeptidic frame. It may be noted that in general, and especially for 11, 12, and 17, the cytotoxicity of the hybrids was much greater than that of the alpha-methylene-gamma-butyrolactone units 24a-g alone.
View Article and Find Full Text PDFAnalogues of naturally occurring antitumor agents, such as distamycin A, which bind in the minor groove of DNA, represent a new class of anticancer compounds currently under investigation. Distamycin A has driven researcher's attention not only for their biological activity, but also for its non intercalative binding to the minor groove of double-stranded B-DNA, where it forms strong reversible complex preferentially at the nucleotide sequences consisting of 4-5 adjacent AT base pairs. The pyrrole-amide skeleton of distamycin A has been also used as DNA sequence selective vehicles for the delivery of alkylating functions to DNA targets, leading to a sharp increase of its cytotoxicity, in comparison to that, very weak, of distamycin itself.
View Article and Find Full Text PDFGlucocorticoids (GC) are widely used in therapy for their many pharmacological properties including antiinflammatory and immunosuppressive actions. However, their use over long periods is hampered by a number of severe side effects. Given the biological properties of nitric oxide (NO) and previous experience with nonsteroidal antiinflammatory agents, we synthesized new chemical entities combining both NO and GC properties.
View Article and Find Full Text PDFCancer treatment is in the need of selective drugs that can interfere specifically with signalling pathways affected during the carcinogenic process. Identification of new potential molecular targets is the key event in the design of new anticancer strategies. Once identified, attempts for the generation of specific molecules to regulate their function can be achieved.
View Article and Find Full Text PDFThe P2X(7) receptor is involved in several processes relevant to inflammation (cytokine release, NO generation, killing of intracellular pathogens, cytotoxicity); thus, it may be an appealing target for pharmacological intervention. The characterization of native and recombinant P2X(7) receptor continues to be hindered by the lack of specific and subtype-selective antagonists. However, a tyrosine derivative named KN-62 exhibits selective P2X(7) receptor-blocking properties.
View Article and Find Full Text PDFTwo potentially hydrophilic platinum (II) complexes 10 and 11 bound to the minor groove binder stallimycin (distamycin A, CAS 636-47-5) by L-cysteine and D,L-2,3-diaminopropionic acid have been synthesized. The in vitro cytotoxicity of both these complexes was evaluated against several cell lines. None of the synthesized platinum complexes showed greater activity than that of cisplatin (cis-DDP, 1) (CAS 15663-27-1).
View Article and Find Full Text PDFThe current study describes the synthesis and biological evaluation of a novel series of 2-amino-3-naphthoylthiophenes, with variable modifications at the 4- and 5-position of the thiophene as well as the naphthoyl ring. Allosteric enhancer activity was measured in several ways: (1) evaluating the effect on forskolin-stimulated cAMP accumulation in the presence of an A(1)-adenosine agonist (CPA) in Chinese hamster ovary (CHO) cells expressing the cloned human A(1)-adenosine receptor (hA(1)AR); (2) ability of these compounds to displace the binding of [(3)H]DPCPX, [(3)H]ZM 241385, and [(3)H]MRE 3008F20 to the ligand binding site of CHO cells expressing the hA(1), hA(2A), and hA(3) adenosine receptors, respectively; (3) effect on the binding of [(3)H]CCPA to membranes from CHO cells expressing hA(1)AR, to rat brain and human cortex membrane preparations containing native adenosine A(1) receptors; (4) kinetics of the dissociation of [(3)H]CCPA from CHO-hA1 membranes. The pharmacological assays compared the various activities to that of the reference compound PD 81,723 (compound 1).
View Article and Find Full Text PDFIn search for novel conformationally constrained analogues of L-glutamic acid, a diastereodivergent synthesis of the four 1-aminospiro[2.2]pentyl-1,4-dicarboxylic acid racemic pairs is reported along with their stereochemical assignment, conformational analysis, and preliminary biological evaluation as potential glutamate (ionotropic and metabotropic) ligands.
View Article and Find Full Text PDFA new series of ring constrained analogues of the P2X7 receptor antagonist KN62 (1-[N,O-bis(1,5-isoquinolinesulfonyl)-N-methyl-L-tyrosyl]-4- phenylpiperazine, CAS 127191-97-3) containing the 1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid core with S configuration in position 3 was synthesised and their antagonist activities were tested on human macrophage cells. While KN62 is a potent antagonist of the P2X7 receptor, these novel compounds are weak antagonists of the purinergic P2X7 receptor and only one compound (5) showed appreciable activity as P2X7 antagonist, which was 30 times weaker than that reported for KN62. Along with compound 5, the derivatives 11 and 25 were the most active inhibitors in this synthesised series.
View Article and Find Full Text PDFA series of benzoyl and cinnamoyl nitrogen mustards tethered to different benzoheterocycles and to oligopyrroles structurally related to netropsin consisting of two pyrrole-amide units and terminating with an amidine moiety have been synthesised and a structure--activity relationship determined. Derivatives 3--10 have been evaluated for their sequence selective alkylating properties and cytotoxicity against human K562 leukaemia cells. They are 2- to 50-fold less cytotoxic than tallimustine, with compound 8 being the most potent member of this series.
View Article and Find Full Text PDFThe reaction of Appel's salt with o-amino nitrile heterocycles 10-19 gave the corresponding 4-chloro-5-heteroimmine-1,2,3-dithiazoles 20-29 which were evaluated for their antibacterial, antifungal and antitumor activity. Although all these N-heteroimines were devoid of significant antibacterial activity, they showed significant antifungal activity. Moreover, the same derivatives represent highly versatile intermediates in heterocyclic synthesis, in fact the pyrazoleimino dithiazoles 20-26 can be converted in one step into 2-cyano derivatives of the corresponding 4-methoxy-pyrazolo[3,4-d]pyrimidines 30-35 by sodium methoxide in refluxing methanol.
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