Maria A Panaro | Università degli Studi di Bari (original) (raw)

Papers by Maria A Panaro

Research paper thumbnail of Cyclooxygenase-2-Derived Prostacyclin Protective Role on Endotoxin-Induced Mouse Cardiomyocyte Mortality

Cardiovascular Toxicology, 2011

Cardiovascular dysfunction characterizes septic shock, inducing multiple organ failure and a high... more Cardiovascular dysfunction characterizes septic shock, inducing multiple organ failure and a high mortality rate. In the heart, it has been shown an up-regulation of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expressions with subsequent overproduction of nitric oxide (NO) and eicosanoids. This study is focused on the links between these products of inflammation and cell loss of mouse cardiomyocytes during treatment by the Salmonella typhimurium lipopolysaccharide (LPS) in presence or in absence of NOS or COX inhibitors. LPS induced RelA/NF-jB p65 activation, iNOS and COX-2 up-regulations, resulting in NO and prostacyclin releases. These effects were reversed by the NO-synthase inhibitor and increased by the specific COX-2 inhibitor. Immunostainings with FITC-conjugated anti-Annexin-V and propidium iodide and caspase 3/7 activity assay showed that cardiomyocyte necrosis was inhibited by L-NA during LPS treatment challenge, while apoptosis was induced in presence of both LPS and NS-398. No effect on LPS cellular injury was observed using the specific cyclooxygenase-1 (COX-1) inhibitor, SC-560. These findings strongly support the hypothesis of a link between iNOS-dependent NO overproduction and LPS-induced cell loss with a selective protective role allotted to COX-2 and deriving prostacyclins.

Research paper thumbnail of Origin and Biological Significance of Shed-Membrane Microparticles

Endocrine‚ Metabolic & Immune Disorders-Drug Targets, 2006

Research paper thumbnail of Renal function in psoriasis patients

European journal of dermatology : EJD

Research paper thumbnail of Recurrence of erythema induratum of Bazin in a patient under chemotherapy for breast cancer

The new microbiologica, 2011

Erythema induratum of Bazin (EIB) is a chronic nodular eruption occurring on the lower legs of yo... more Erythema induratum of Bazin (EIB) is a chronic nodular eruption occurring on the lower legs of young and middleaged women which is considered the most common tuberculid. A 54-year-old woman, in treatment with chemotherapy for breast cancer, presented subcutaneous erythematous plaques and nodules on the lower limbs. She had been diagnosed with EIB 3 years earlier and diagnostic work-up showed at that time signs suggestive of latent tuberculosis. The suspect of a recurrent form of EIB was confirmed by histopathological examination. A peculiar feature of our report consists in the recurrence of EIB, which is regarded as a hyperergic response against M. tuberculosis antigens, in a patient who was receiving chemotherapy with well-known immunosuppressive effects.

Research paper thumbnail of Role of serum uric acid in conditioning the association of psoriasis with metabolic syndrome

European journal of dermatology : EJD

Research paper thumbnail of Evidences for iNOS expression and nitric oxide production in the human macrophages

Current drug targets. Immune, endocrine and metabolic disorders, 2003

Nitric oxide (NO) is a pleiotropic mediator of numerous biological processes, including smooth mu... more Nitric oxide (NO) is a pleiotropic mediator of numerous biological processes, including smooth muscle relaxation, neurotransmission and defence against pathogens. In addition, NO is involved in the pathogenesis and control of inflammation, tumors, autoimmunity, and infectious and chronic degenerative diseases. NO, a highly reactive radical, is produced from L-arginine and oxygen by the enzyme NO synthase (NOS). Three NOS isoforms have been identified: two distinct NOS isoforms are constitutively expressed in cells, whereas a third isoform, inducible NOS (iNOS), is transcribed in response to specific stimuli. In particular, iNOS is responsible for the discontinuous synthesis of high amounts of NO and was originally characterized in murine macrophages after exposure to cytokines and/or microbial products. A wide range of microorganisms is sensibly inhibited in its development by NO, like fungi, bacteria, protozoa and viruses. Although NO production and its antimicrobial effect appear ...

Research paper thumbnail of Embryonal cardiotoxicity of the Helicobacter pylori lipopolysaccharide

Current drug targets. Immune, endocrine and metabolic disorders, 2001

Helicobacter (H.) pylori is the causative agent of the peptic ulcer disease and a co-factor in th... more Helicobacter (H.) pylori is the causative agent of the peptic ulcer disease and a co-factor in the development of gastric malignancies. Recently, it has been maintained that chronic H. pylori infections in adults are linked to a higher risk of coronary heart diseases. In this respect, the acute toxic effects of the H. pylori lipopolysaccharide (LPS) on embryonal cardiomyocytes at different developmental stages was evaluated. White Leghorn chick embryos and smooth (S)--form NCTC 11637 strain H. pylori organisms were used. Both whole heath-killed H. pylori suspensions (3.10(6) bacteria/egg) and isolated S-LPS (500 ng/egg) or S-Lipid A (500 ng/egg) were non-lethal to 4-day embryos, becoming moderately lethal (5% to 30%) to 6- and 8-day embryos and highly lethal (> 90%) to 10- to 17-day embryos. The contractile activity of isolated atrial fragments from 10-day embryos was completely inhibited, within 5 min, following treatments with heath-killed H. pylori (3 x 10(6)/ml), or S-LPS (50...

Research paper thumbnail of Macrophage chemotactic protein-1 and macrophage inflammatory protein-1 alpha induce nitric oxide release and enhance parasite killing in Leishmania infantum-infected human macrophages

Clinical and experimental medicine, 2002

Chemokines are a group of structurally defined small proteins that act as chemoattractants for le... more Chemokines are a group of structurally defined small proteins that act as chemoattractants for leukocytes and are involved in many different biological activities, including leukocyte activation for antimicrobial mechanisms. We studied the effect of the chemokines monocyte chemotactic protein (MCP)-1 and macrophage inflammatory protein (MIP)-1 alpha on nitric oxide release and parasitocidal ability of peripheral blood-derived human macrophages in vitro infected with Leishmania infantum, zymodeme MON1. In infected human macrophages, treatment with MCP-1 or MIP-1 alpha significantly enhanced nitric oxide production and leishmanicidal ability, compared with untreated cells, to the same levels induced by interferon-gamma. Both nitric oxide release and parasitocidal ability of macrophages were significantly reduced by addition of L- N(G)monomethylarginine ( L-NMMA), which is a competitive inhibitor of the L-arginine nitric oxide pathway. These data suggest that MCP-1 and MIP-1 alpha medi...

Research paper thumbnail of Pathogenic potential of SLC25A15 mutations assessed by transport assays and complementation of Saccharomyces cerevisiae ORT1 null mutant

Molecular Genetics and Metabolism, 2015

HHH syndrome is an autosomal recessive urea cycle disorder caused by alterations in the SLC25A15 ... more HHH syndrome is an autosomal recessive urea cycle disorder caused by alterations in the SLC25A15 gene encoding the mitochondrial ornithine carrier 1, which catalyzes the transport of cytosolic ornithine into the mitochondria in exchange for intramitochondrial citrulline. In this study the functional effects of several SLC25A15 missense mutations p.G27R, p.M37R, p.N74A, p.F188L, p.F188Y, p.S200K, p.R275Q and p.R275K have been tested by transport assays in reconstituted liposomes and complementation of Saccharomyces cerevisiae ORT1 null mutant in arginine-less synthetic complete medium. The HHH syndrome-causing mutations p.G27R, p.M37R, p.F188L and p.R275Q had impaired transport and did not complement ORT1∆ cells (except p.M37R slightly after 5days in solid medium). The experimentally produced mutations p.N74A, p.S200K and p.R275K exhibited normal or considerable transport activity and complemented ORT1∆ cells after 3days (p.N74A, p.S200K) or 5days (p.R275K) incubation. Furthermore, the experimentally produced p.F188Y mutation displayed a substantial transport activity but did not complement the ORT1∆ cells in both liquid and solid media. In view of the disagreement in the results obtained between the two methods, it is recommended that the method of complementing the S. cerevisiae ORT1 knockout strain is used complimentary with the measurement of the catalytic activity, in order to distinguish HHH syndrome-causing mutations from isomorphisms.

Research paper thumbnail of Conservation/Mutation in the Splice Sites of Cytokine Receptor Genes of Mouse and Human

International Journal of Evolutionary Biology, 2013

Conservation/mutation in the intronic initial and terminal hexanucleotides was studied in 26 orth... more Conservation/mutation in the intronic initial and terminal hexanucleotides was studied in 26 orthologous cytokine receptor genes of Mouse and Human. Introns began and ended with the canonical dinucleotides GT and AG, respectively. Identical configurations were found in 57% of the 5 hexanucleotides and 28% of the 3 hexanucleotides. The actual conservation percentages of the individual variable nucleotides at each position in the hexanucleotides were determined, and the theoretical rates of conservation of groups of three nucleotides were calculated under the hypothesis of a mutual evolutionary independence of the neighboring nucleotides (random association). Analysis of the actual conservation of groups of variable nucleotides showed that, at 5 , GTGAGx was significantly more expressed and GTAAGx was significantly less expressed, as compared to the random association. At 3 , TTTxAG and xTGCAG were overexpressed as compared to a random association. Study of Mouse and Human transcript variants involving the splice sites showed that most variants were not inherited from the common ancestor but emerged during the process of speciation. In some variants the silencing of a terminal hexanucleotide determined skipping of the downstream exon; in other variants the constitutive splicing hexanucleotide was replaced by another potential, in-frame, splicing hexanucleotide, leading to alterations of exon lengths.

Research paper thumbnail of Expression of UDP-glucuronosyltransferase 1A6 isoform in Caco-2 cells stimulated with lipopolysaccharide

Research paper thumbnail of Differential Conservation of Nucleotides and Conservation/Mutation Correlations Between Nucleotides, with Special Reference to CXC 1 and 4 and FP Receptors Involved in Immune Regulation

Endocrine, Metabolic & Immune Disorders - Drug Targets, 2009

Random mutations of the first nucleotide of a coding triplet alter the hydropathic character of 2... more Random mutations of the first nucleotide of a coding triplet alter the hydropathic character of 27 % of the hydrophobic amino acids and of 23 % of the hydrophilic amino acids, while random mutations of the second nucleotide alter the hydropathic character of 82 % of the hydrophobic amino acids and of 47 % of the hydrophilic amino acids. In cases of a change of the hydropathic character, a second random mutation in the previously unmutated first or second nucleotide causes reversion to the original character of an additional 11 % of the originally hydrophobic-coding triplets and an additional 14 % of the originally hydrophilic-coding triplets (on average). Thus, a selection oriented towards the preservation of the hydropathic character of amino acids may be expected to eventually result in a higher conservation of the second nucleotide (as compared to the first). In the case of uncorrected mutations of one of the two first nucleotides, it may be expected that appropriate second mutations in the other unaffected nucleotide will be positively selected. This would result in a positive correlation between the conservation/mutation indexes of the two first nucleotides, as these would be prevailingly either both conserved or both mutated. We examined six groups of coding mRNA sequences: chemokine CXC 1 and 4 and formyl peptide receptors; a group comprising different receptors of the rhodopsin-like superfamily, together with some viral sequences which share significant homologies with these receptors; a group of viral sequences with homologies with the rhodopsin-like receptors; a group of solute carriers. In all the experimental groups the second nucleotide of the triplet was the most conserved and a significant positive correlation existed between conservation/mutation indexes of the two first nucleotides. Similar conservation/mutation patterns could be of more general occurrence in the genome, as a consequence of selection processes.

Research paper thumbnail of Mutation, Selection and the Amino Acid Hydropathic Character: A Study on Receptor Genes Involved in Immune and Non-Immune Functions

Endocrine, Metabolic & Immune Disorders - Drug Targets, 2009

In some mRNA sequences, namely those of formyl peptide receptors and chemokine CXC receptors 4, i... more In some mRNA sequences, namely those of formyl peptide receptors and chemokine CXC receptors 4, it has been observed that the second nucleotide (nt) of the coding triplets is significantly more highly conserved than the first nt and the correlation between the conservation indexes of the first two nt is positive and significantly higher than the "basic" correlation usually found between adjacent nt. A theoretical analysis demonstrated that random mutations in the first nt preserve hydrophobicity in 73 % of triplets coding for hydrophobic amino acids (aa) and hydrophilicity in 77 % of triplets coding for hydrophilic aa, while random mutations in the second nt preserve hydrophobicity in 18 % of triplets coding for hydrophobic aa and hydrophilicity in 53 % of triplets coding for hydrophilic aa. When the triplets which had changed their hydropathic aa coding character underwent a second random mutation in the previously unmutated first or second nt, an additional 11 % of the originally hydrophobic-coding triplets reverted to hydrophobicity and an additional 14 % of the originally hydrophilic-coding triplets reverted to hydrophilicity. This analysis provides a rationale for why a higher number of mutations in the second nt are presumably negatively selected and a number of double mutations in the first and second nt presumably are positively selected, in cases when a mutation in one of the two is not reverted.

Research paper thumbnail of The HIV-1 Rev Binding Family of Proteins: The Dog Proteins as a Study Model

Endocrine‚ Metabolic & Immune Disorders-Drug Targets, 2008

Various proteins that are required for the building of new complete human immunodeficiency type 1... more Various proteins that are required for the building of new complete human immunodeficiency type 1 virions (HIV-1) are coded by unspliced or partly spliced virus-derived mRNAs. HIV-1 has developed special strategies for moving these mRNAs to the cytoplasm to be translated. In the nucleus of the infected cell the virus-derived protein Regulator of expression of viral proteins (Rev) can bind both the viral intron-containing mRNAs and the cellular co-factor HIV-1 Rev binding protein (HRB) and this complex may be shuttled through the nuclear pores. HRB genes have been relatively well conserved during evolution, from Drosophila to humans. However, as a consequence of reading-frame shifts due to nt insertions/deletions, the protein products generated may differ considerably from the prototypal HRB protein, which comprises one Arf-GAP zinc finger domain, several Phenylalanine-Glycine (FG) motifs and four Asparagine-Proline-Phenylalanine (NPF) motifs. This variability is best exemplified by four HRB proteins of the dog, which are discussed here in more detail. The hypothesis is advanced that atypical HRB proteins may not be able to bind Rev and possibly have other, still undetermined, functions. Since the cellular co-factor HRB is essential for viral replication and spread but is not required for cell viability and main bodily functions, it might be an attractive candidate for anti-HIV-1 drug targeting.

Research paper thumbnail of Variational Approach to the Problem of the Minimum Induced Drag of Wings

Springer Optimization and Its Applications, 2009

A closed form solution of the problem of the minimum induced drag of a finite span straight wing ... more A closed form solution of the problem of the minimum induced drag of a finite span straight wing was given by Prandtl. In this paper, a mathematical theory, based on a variational approach, is proposed in order to revise such a problem and provide one with a support for optimizing more complex wing configurations, which are becoming of interest for future aircraft. The first step of the theory consists in finding a class of functions (lift distributions) for which the induced drag functional is well defined. Then, in this class, the functional to be minimized is proved to be strictly convex; taking into account this result, it is proved that the global minimum solution exists and is unique. In Sect. Subsequently, we introduce the Image Space Analysis associated with a constrained extremum problem; this allows us to define the Lagrangian dual of the problem of the minimum induced drag, and show how such a dual problem can supply a new approach to the design. After having obtained the Prandtl exact solution in the context of a variational formulation, a numerical algorithm, based on the Ritz method, is presented, and its convergence is proved.

Research paper thumbnail of Origin and Biological Significance of Shed-Membrane Microparticles

Endocrine‚ Metabolic & Immune Disorders-Drug Targets, 2006

Research paper thumbnail of A new generation of MDR modulating agents with dual activity: P-gp inhibitor and iNOS inducer agents

Toxicology in Vitro, 2011

MultiDrug Resistance (MDR) is due to the ability of some ATPase transporters to efflux chemothera... more MultiDrug Resistance (MDR) is due to the ability of some ATPase transporters to efflux chemotherapeutic agents out from tumor cells decreasing the endocellular concentration for the pharmacological effect, causing cancer cells chemoresistance.

Research paper thumbnail of Plasma membrane damage sensing and repairing. Role of heterotrimeric G-proteins and the cytoskeleton

Toxicology in Vitro, 2011

Different toxic agents, derived from bacteria, viruses or cells of the immune system, as well as ... more Different toxic agents, derived from bacteria, viruses or cells of the immune system, as well as mechanical forces generated during cell locomotion are able to open pores in the cell plasma membrane. Most of these biological agents operate through specific receptors. We studied the formation and resealing of the "non-specific" plasma membrane pores generated by the mild non-ionic detergent Triton X-100. In HL-60-derived granulocytic cells plasma membrane pore opening after a 1-h treatment with Triton X-100 is documented by entry into the cell of the membrane impermeant dye ethidium bromide. As a consequence of the opening of pores the intracellular K(+) concentration falls dramatically, the cytosolic pH diminishes and the cell membrane is depolarized. Furthermore the cells acquire a polarized morphology, demonstrating the involvement of the actin cytoskeleton. At the Triton concentration used the membrane lesions are progressively repaired and by 8h the impermeability to ethidium bromide is restored and the intracellular K(+) concentration is virtually normal. Following treatments with Triton+Pertussis toxin, Triton+Cytochalasin, or Triton+Pertussis toxin+Cytochalasin the progress of membrane repair is dramatically slowed and is no longer completed by 8h. It is concluded that the membrane damage activates pertussis-sensitive G-proteins which likely act as sensors of the damage, while both G-proteins and the actin cytoskeleton are involved in the membrane repair mechanism.

Research paper thumbnail of Evaluation of macrophage killing ability and nitric oxide production in dogs vaccinated with killed Leishmania promastigotes

Parasitology International, 1998

Research paper thumbnail of Cytokine expression in dogs with natural Leishmania infantum infection

Parasitology, 2009

The aim of this study was to evaluate cytokine expression in 22 Leishmania infantum naturally inf... more The aim of this study was to evaluate cytokine expression in 22 Leishmania infantum naturally infected dogs, in order to correlate this parameter with the clinical status of infected animals. After 4 and 8 months from the first diagnosis of Leishmania infection, clinical and laboratory examination of dogs was performed and peripheral blood mononuclear cells (PBMC) were isolated. The cytokine profile was analysed in terms of IFN-gamma, IL-4, IL-10 and TNF-alpha mRNA expression in cultured PBMC by a semi-quantitative reverse transcriptase-PCR. Thirteen out of 22 Leishmania-infected dogs remained asymptomatic in the follow-up, while 9 showed clinical signs of leishmaniasis. IL-4, IL-10, TNF-alpha and IFN-gamma mRNA levels were not significantly different in asymptomatic compared to symptomatic animals 4 months from the diagnosis of Leishmania infection, but were significantly higher in symptomatic versus asymptomatic dogs after 8 months from diagnosis. In addition, IL-4, IL-10 and TNF-alpha mRNA levels significantly increased only in symptomatic dogs at 8 months, in comparison to the levels found at 4 months. These results show a mixed Th1 and Th2 cytokine response in Leishmania-infected dogs, with higher cytokine expression in dogs with manifest clinical disease, during the second follow-up after 8 months from the first diagnosis of infection.

Research paper thumbnail of Cyclooxygenase-2-Derived Prostacyclin Protective Role on Endotoxin-Induced Mouse Cardiomyocyte Mortality

Cardiovascular Toxicology, 2011

Cardiovascular dysfunction characterizes septic shock, inducing multiple organ failure and a high... more Cardiovascular dysfunction characterizes septic shock, inducing multiple organ failure and a high mortality rate. In the heart, it has been shown an up-regulation of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expressions with subsequent overproduction of nitric oxide (NO) and eicosanoids. This study is focused on the links between these products of inflammation and cell loss of mouse cardiomyocytes during treatment by the Salmonella typhimurium lipopolysaccharide (LPS) in presence or in absence of NOS or COX inhibitors. LPS induced RelA/NF-jB p65 activation, iNOS and COX-2 up-regulations, resulting in NO and prostacyclin releases. These effects were reversed by the NO-synthase inhibitor and increased by the specific COX-2 inhibitor. Immunostainings with FITC-conjugated anti-Annexin-V and propidium iodide and caspase 3/7 activity assay showed that cardiomyocyte necrosis was inhibited by L-NA during LPS treatment challenge, while apoptosis was induced in presence of both LPS and NS-398. No effect on LPS cellular injury was observed using the specific cyclooxygenase-1 (COX-1) inhibitor, SC-560. These findings strongly support the hypothesis of a link between iNOS-dependent NO overproduction and LPS-induced cell loss with a selective protective role allotted to COX-2 and deriving prostacyclins.

Research paper thumbnail of Origin and Biological Significance of Shed-Membrane Microparticles

Endocrine‚ Metabolic & Immune Disorders-Drug Targets, 2006

Research paper thumbnail of Renal function in psoriasis patients

European journal of dermatology : EJD

Research paper thumbnail of Recurrence of erythema induratum of Bazin in a patient under chemotherapy for breast cancer

The new microbiologica, 2011

Erythema induratum of Bazin (EIB) is a chronic nodular eruption occurring on the lower legs of yo... more Erythema induratum of Bazin (EIB) is a chronic nodular eruption occurring on the lower legs of young and middleaged women which is considered the most common tuberculid. A 54-year-old woman, in treatment with chemotherapy for breast cancer, presented subcutaneous erythematous plaques and nodules on the lower limbs. She had been diagnosed with EIB 3 years earlier and diagnostic work-up showed at that time signs suggestive of latent tuberculosis. The suspect of a recurrent form of EIB was confirmed by histopathological examination. A peculiar feature of our report consists in the recurrence of EIB, which is regarded as a hyperergic response against M. tuberculosis antigens, in a patient who was receiving chemotherapy with well-known immunosuppressive effects.

Research paper thumbnail of Role of serum uric acid in conditioning the association of psoriasis with metabolic syndrome

European journal of dermatology : EJD

Research paper thumbnail of Evidences for iNOS expression and nitric oxide production in the human macrophages

Current drug targets. Immune, endocrine and metabolic disorders, 2003

Nitric oxide (NO) is a pleiotropic mediator of numerous biological processes, including smooth mu... more Nitric oxide (NO) is a pleiotropic mediator of numerous biological processes, including smooth muscle relaxation, neurotransmission and defence against pathogens. In addition, NO is involved in the pathogenesis and control of inflammation, tumors, autoimmunity, and infectious and chronic degenerative diseases. NO, a highly reactive radical, is produced from L-arginine and oxygen by the enzyme NO synthase (NOS). Three NOS isoforms have been identified: two distinct NOS isoforms are constitutively expressed in cells, whereas a third isoform, inducible NOS (iNOS), is transcribed in response to specific stimuli. In particular, iNOS is responsible for the discontinuous synthesis of high amounts of NO and was originally characterized in murine macrophages after exposure to cytokines and/or microbial products. A wide range of microorganisms is sensibly inhibited in its development by NO, like fungi, bacteria, protozoa and viruses. Although NO production and its antimicrobial effect appear ...

Research paper thumbnail of Embryonal cardiotoxicity of the Helicobacter pylori lipopolysaccharide

Current drug targets. Immune, endocrine and metabolic disorders, 2001

Helicobacter (H.) pylori is the causative agent of the peptic ulcer disease and a co-factor in th... more Helicobacter (H.) pylori is the causative agent of the peptic ulcer disease and a co-factor in the development of gastric malignancies. Recently, it has been maintained that chronic H. pylori infections in adults are linked to a higher risk of coronary heart diseases. In this respect, the acute toxic effects of the H. pylori lipopolysaccharide (LPS) on embryonal cardiomyocytes at different developmental stages was evaluated. White Leghorn chick embryos and smooth (S)--form NCTC 11637 strain H. pylori organisms were used. Both whole heath-killed H. pylori suspensions (3.10(6) bacteria/egg) and isolated S-LPS (500 ng/egg) or S-Lipid A (500 ng/egg) were non-lethal to 4-day embryos, becoming moderately lethal (5% to 30%) to 6- and 8-day embryos and highly lethal (> 90%) to 10- to 17-day embryos. The contractile activity of isolated atrial fragments from 10-day embryos was completely inhibited, within 5 min, following treatments with heath-killed H. pylori (3 x 10(6)/ml), or S-LPS (50...

Research paper thumbnail of Macrophage chemotactic protein-1 and macrophage inflammatory protein-1 alpha induce nitric oxide release and enhance parasite killing in Leishmania infantum-infected human macrophages

Clinical and experimental medicine, 2002

Chemokines are a group of structurally defined small proteins that act as chemoattractants for le... more Chemokines are a group of structurally defined small proteins that act as chemoattractants for leukocytes and are involved in many different biological activities, including leukocyte activation for antimicrobial mechanisms. We studied the effect of the chemokines monocyte chemotactic protein (MCP)-1 and macrophage inflammatory protein (MIP)-1 alpha on nitric oxide release and parasitocidal ability of peripheral blood-derived human macrophages in vitro infected with Leishmania infantum, zymodeme MON1. In infected human macrophages, treatment with MCP-1 or MIP-1 alpha significantly enhanced nitric oxide production and leishmanicidal ability, compared with untreated cells, to the same levels induced by interferon-gamma. Both nitric oxide release and parasitocidal ability of macrophages were significantly reduced by addition of L- N(G)monomethylarginine ( L-NMMA), which is a competitive inhibitor of the L-arginine nitric oxide pathway. These data suggest that MCP-1 and MIP-1 alpha medi...

Research paper thumbnail of Pathogenic potential of SLC25A15 mutations assessed by transport assays and complementation of Saccharomyces cerevisiae ORT1 null mutant

Molecular Genetics and Metabolism, 2015

HHH syndrome is an autosomal recessive urea cycle disorder caused by alterations in the SLC25A15 ... more HHH syndrome is an autosomal recessive urea cycle disorder caused by alterations in the SLC25A15 gene encoding the mitochondrial ornithine carrier 1, which catalyzes the transport of cytosolic ornithine into the mitochondria in exchange for intramitochondrial citrulline. In this study the functional effects of several SLC25A15 missense mutations p.G27R, p.M37R, p.N74A, p.F188L, p.F188Y, p.S200K, p.R275Q and p.R275K have been tested by transport assays in reconstituted liposomes and complementation of Saccharomyces cerevisiae ORT1 null mutant in arginine-less synthetic complete medium. The HHH syndrome-causing mutations p.G27R, p.M37R, p.F188L and p.R275Q had impaired transport and did not complement ORT1∆ cells (except p.M37R slightly after 5days in solid medium). The experimentally produced mutations p.N74A, p.S200K and p.R275K exhibited normal or considerable transport activity and complemented ORT1∆ cells after 3days (p.N74A, p.S200K) or 5days (p.R275K) incubation. Furthermore, the experimentally produced p.F188Y mutation displayed a substantial transport activity but did not complement the ORT1∆ cells in both liquid and solid media. In view of the disagreement in the results obtained between the two methods, it is recommended that the method of complementing the S. cerevisiae ORT1 knockout strain is used complimentary with the measurement of the catalytic activity, in order to distinguish HHH syndrome-causing mutations from isomorphisms.

Research paper thumbnail of Conservation/Mutation in the Splice Sites of Cytokine Receptor Genes of Mouse and Human

International Journal of Evolutionary Biology, 2013

Conservation/mutation in the intronic initial and terminal hexanucleotides was studied in 26 orth... more Conservation/mutation in the intronic initial and terminal hexanucleotides was studied in 26 orthologous cytokine receptor genes of Mouse and Human. Introns began and ended with the canonical dinucleotides GT and AG, respectively. Identical configurations were found in 57% of the 5 hexanucleotides and 28% of the 3 hexanucleotides. The actual conservation percentages of the individual variable nucleotides at each position in the hexanucleotides were determined, and the theoretical rates of conservation of groups of three nucleotides were calculated under the hypothesis of a mutual evolutionary independence of the neighboring nucleotides (random association). Analysis of the actual conservation of groups of variable nucleotides showed that, at 5 , GTGAGx was significantly more expressed and GTAAGx was significantly less expressed, as compared to the random association. At 3 , TTTxAG and xTGCAG were overexpressed as compared to a random association. Study of Mouse and Human transcript variants involving the splice sites showed that most variants were not inherited from the common ancestor but emerged during the process of speciation. In some variants the silencing of a terminal hexanucleotide determined skipping of the downstream exon; in other variants the constitutive splicing hexanucleotide was replaced by another potential, in-frame, splicing hexanucleotide, leading to alterations of exon lengths.

Research paper thumbnail of Expression of UDP-glucuronosyltransferase 1A6 isoform in Caco-2 cells stimulated with lipopolysaccharide

Research paper thumbnail of Differential Conservation of Nucleotides and Conservation/Mutation Correlations Between Nucleotides, with Special Reference to CXC 1 and 4 and FP Receptors Involved in Immune Regulation

Endocrine, Metabolic & Immune Disorders - Drug Targets, 2009

Random mutations of the first nucleotide of a coding triplet alter the hydropathic character of 2... more Random mutations of the first nucleotide of a coding triplet alter the hydropathic character of 27 % of the hydrophobic amino acids and of 23 % of the hydrophilic amino acids, while random mutations of the second nucleotide alter the hydropathic character of 82 % of the hydrophobic amino acids and of 47 % of the hydrophilic amino acids. In cases of a change of the hydropathic character, a second random mutation in the previously unmutated first or second nucleotide causes reversion to the original character of an additional 11 % of the originally hydrophobic-coding triplets and an additional 14 % of the originally hydrophilic-coding triplets (on average). Thus, a selection oriented towards the preservation of the hydropathic character of amino acids may be expected to eventually result in a higher conservation of the second nucleotide (as compared to the first). In the case of uncorrected mutations of one of the two first nucleotides, it may be expected that appropriate second mutations in the other unaffected nucleotide will be positively selected. This would result in a positive correlation between the conservation/mutation indexes of the two first nucleotides, as these would be prevailingly either both conserved or both mutated. We examined six groups of coding mRNA sequences: chemokine CXC 1 and 4 and formyl peptide receptors; a group comprising different receptors of the rhodopsin-like superfamily, together with some viral sequences which share significant homologies with these receptors; a group of viral sequences with homologies with the rhodopsin-like receptors; a group of solute carriers. In all the experimental groups the second nucleotide of the triplet was the most conserved and a significant positive correlation existed between conservation/mutation indexes of the two first nucleotides. Similar conservation/mutation patterns could be of more general occurrence in the genome, as a consequence of selection processes.

Research paper thumbnail of Mutation, Selection and the Amino Acid Hydropathic Character: A Study on Receptor Genes Involved in Immune and Non-Immune Functions

Endocrine, Metabolic & Immune Disorders - Drug Targets, 2009

In some mRNA sequences, namely those of formyl peptide receptors and chemokine CXC receptors 4, i... more In some mRNA sequences, namely those of formyl peptide receptors and chemokine CXC receptors 4, it has been observed that the second nucleotide (nt) of the coding triplets is significantly more highly conserved than the first nt and the correlation between the conservation indexes of the first two nt is positive and significantly higher than the "basic" correlation usually found between adjacent nt. A theoretical analysis demonstrated that random mutations in the first nt preserve hydrophobicity in 73 % of triplets coding for hydrophobic amino acids (aa) and hydrophilicity in 77 % of triplets coding for hydrophilic aa, while random mutations in the second nt preserve hydrophobicity in 18 % of triplets coding for hydrophobic aa and hydrophilicity in 53 % of triplets coding for hydrophilic aa. When the triplets which had changed their hydropathic aa coding character underwent a second random mutation in the previously unmutated first or second nt, an additional 11 % of the originally hydrophobic-coding triplets reverted to hydrophobicity and an additional 14 % of the originally hydrophilic-coding triplets reverted to hydrophilicity. This analysis provides a rationale for why a higher number of mutations in the second nt are presumably negatively selected and a number of double mutations in the first and second nt presumably are positively selected, in cases when a mutation in one of the two is not reverted.

Research paper thumbnail of The HIV-1 Rev Binding Family of Proteins: The Dog Proteins as a Study Model

Endocrine‚ Metabolic & Immune Disorders-Drug Targets, 2008

Various proteins that are required for the building of new complete human immunodeficiency type 1... more Various proteins that are required for the building of new complete human immunodeficiency type 1 virions (HIV-1) are coded by unspliced or partly spliced virus-derived mRNAs. HIV-1 has developed special strategies for moving these mRNAs to the cytoplasm to be translated. In the nucleus of the infected cell the virus-derived protein Regulator of expression of viral proteins (Rev) can bind both the viral intron-containing mRNAs and the cellular co-factor HIV-1 Rev binding protein (HRB) and this complex may be shuttled through the nuclear pores. HRB genes have been relatively well conserved during evolution, from Drosophila to humans. However, as a consequence of reading-frame shifts due to nt insertions/deletions, the protein products generated may differ considerably from the prototypal HRB protein, which comprises one Arf-GAP zinc finger domain, several Phenylalanine-Glycine (FG) motifs and four Asparagine-Proline-Phenylalanine (NPF) motifs. This variability is best exemplified by four HRB proteins of the dog, which are discussed here in more detail. The hypothesis is advanced that atypical HRB proteins may not be able to bind Rev and possibly have other, still undetermined, functions. Since the cellular co-factor HRB is essential for viral replication and spread but is not required for cell viability and main bodily functions, it might be an attractive candidate for anti-HIV-1 drug targeting.

Research paper thumbnail of Variational Approach to the Problem of the Minimum Induced Drag of Wings

Springer Optimization and Its Applications, 2009

A closed form solution of the problem of the minimum induced drag of a finite span straight wing ... more A closed form solution of the problem of the minimum induced drag of a finite span straight wing was given by Prandtl. In this paper, a mathematical theory, based on a variational approach, is proposed in order to revise such a problem and provide one with a support for optimizing more complex wing configurations, which are becoming of interest for future aircraft. The first step of the theory consists in finding a class of functions (lift distributions) for which the induced drag functional is well defined. Then, in this class, the functional to be minimized is proved to be strictly convex; taking into account this result, it is proved that the global minimum solution exists and is unique. In Sect. Subsequently, we introduce the Image Space Analysis associated with a constrained extremum problem; this allows us to define the Lagrangian dual of the problem of the minimum induced drag, and show how such a dual problem can supply a new approach to the design. After having obtained the Prandtl exact solution in the context of a variational formulation, a numerical algorithm, based on the Ritz method, is presented, and its convergence is proved.

Research paper thumbnail of Origin and Biological Significance of Shed-Membrane Microparticles

Endocrine‚ Metabolic & Immune Disorders-Drug Targets, 2006

Research paper thumbnail of A new generation of MDR modulating agents with dual activity: P-gp inhibitor and iNOS inducer agents

Toxicology in Vitro, 2011

MultiDrug Resistance (MDR) is due to the ability of some ATPase transporters to efflux chemothera... more MultiDrug Resistance (MDR) is due to the ability of some ATPase transporters to efflux chemotherapeutic agents out from tumor cells decreasing the endocellular concentration for the pharmacological effect, causing cancer cells chemoresistance.

Research paper thumbnail of Plasma membrane damage sensing and repairing. Role of heterotrimeric G-proteins and the cytoskeleton

Toxicology in Vitro, 2011

Different toxic agents, derived from bacteria, viruses or cells of the immune system, as well as ... more Different toxic agents, derived from bacteria, viruses or cells of the immune system, as well as mechanical forces generated during cell locomotion are able to open pores in the cell plasma membrane. Most of these biological agents operate through specific receptors. We studied the formation and resealing of the "non-specific" plasma membrane pores generated by the mild non-ionic detergent Triton X-100. In HL-60-derived granulocytic cells plasma membrane pore opening after a 1-h treatment with Triton X-100 is documented by entry into the cell of the membrane impermeant dye ethidium bromide. As a consequence of the opening of pores the intracellular K(+) concentration falls dramatically, the cytosolic pH diminishes and the cell membrane is depolarized. Furthermore the cells acquire a polarized morphology, demonstrating the involvement of the actin cytoskeleton. At the Triton concentration used the membrane lesions are progressively repaired and by 8h the impermeability to ethidium bromide is restored and the intracellular K(+) concentration is virtually normal. Following treatments with Triton+Pertussis toxin, Triton+Cytochalasin, or Triton+Pertussis toxin+Cytochalasin the progress of membrane repair is dramatically slowed and is no longer completed by 8h. It is concluded that the membrane damage activates pertussis-sensitive G-proteins which likely act as sensors of the damage, while both G-proteins and the actin cytoskeleton are involved in the membrane repair mechanism.

Research paper thumbnail of Evaluation of macrophage killing ability and nitric oxide production in dogs vaccinated with killed Leishmania promastigotes

Parasitology International, 1998

Research paper thumbnail of Cytokine expression in dogs with natural Leishmania infantum infection

Parasitology, 2009

The aim of this study was to evaluate cytokine expression in 22 Leishmania infantum naturally inf... more The aim of this study was to evaluate cytokine expression in 22 Leishmania infantum naturally infected dogs, in order to correlate this parameter with the clinical status of infected animals. After 4 and 8 months from the first diagnosis of Leishmania infection, clinical and laboratory examination of dogs was performed and peripheral blood mononuclear cells (PBMC) were isolated. The cytokine profile was analysed in terms of IFN-gamma, IL-4, IL-10 and TNF-alpha mRNA expression in cultured PBMC by a semi-quantitative reverse transcriptase-PCR. Thirteen out of 22 Leishmania-infected dogs remained asymptomatic in the follow-up, while 9 showed clinical signs of leishmaniasis. IL-4, IL-10, TNF-alpha and IFN-gamma mRNA levels were not significantly different in asymptomatic compared to symptomatic animals 4 months from the diagnosis of Leishmania infection, but were significantly higher in symptomatic versus asymptomatic dogs after 8 months from diagnosis. In addition, IL-4, IL-10 and TNF-alpha mRNA levels significantly increased only in symptomatic dogs at 8 months, in comparison to the levels found at 4 months. These results show a mixed Th1 and Th2 cytokine response in Leishmania-infected dogs, with higher cytokine expression in dogs with manifest clinical disease, during the second follow-up after 8 months from the first diagnosis of infection.