Publications by authors named "Conter C"

Background And Aims: Alcohol-associated liver disease (ALD) is a leading cause of liver-related mortality worldwide, with limited treatment options beyond abstinence and liver transplantation. Chronic alcohol consumption has been linked to magnesium (Mg 2+ ) deficiency, which can influence liver disease progression. The mechanisms underlying Mg 2+ homeostasis dysregulation in ALD remain elusive.

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  • Drug-induced liver injury (DILI), particularly from acetaminophen (APAP) overdose, is a major factor in acute liver failure and liver transplants in the Western world.
  • Research shows that neddylation, a modification important for mitochondrial function, is increased in liver samples from APAP injury patients and mice with APAP overdose.
  • The inhibitor MLN4924 reduces liver cell damage and enhances regeneration in APAP injury, and the study identifies crucial elements in this process, suggesting new avenues for targeted DILI treatments.
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The escalating drug resistance among microorganisms underscores the urgent need for innovative therapeutic strategies and a comprehensive understanding of bacteria's defense mechanisms against oxidative stress and antibiotics. Among the recently discovered barriers, the endogenous production of hydrogen sulfide (HS) via the reverse transsulfuration pathway, emerges as a noteworthy factor. In this study, we have explored the catalytic capabilities and crystal structure of cystathionine γ-lyase from Pseudomonas aeruginosa (PaCGL), a multidrug-opportunistic pathogen chiefly responsible for nosocomial infections.

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Homocystinuria is a rare disease caused by mutations in the CBS gene that results in a deficiency of cystathionine β-synthase (CBS). CBS is an essential pyridoxal 5'-phosphate (PLP)-dependent enzyme in the transsulfuration pathway, responsible for combining serine with homocysteine to produce cystathionine, whose activity is enhanced by the allosteric regulator S-adenosylmethionine (SAM). CBS also plays a role in generating hydrogen sulfide (H2S), a gaseous signaling molecule with diverse regulatory functions within the vascular, nervous, and immune systems.

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Plasma membrane-associated Cation-binding Protein 1 (PCaP1) belongs to the plant-unique DREPP protein family with largely unknown biological functions but ascertained roles in plant development and calcium (Ca) signaling. PCaP1 is anchored to the plasma membrane via N-myristoylation and a polybasic cluster, and its N-terminal region can bind Ca/calmodulin (CaM). However, the molecular determinants of PCaP1-Ca-CaM interaction and the functional impact of myristoylation in the complex formation and Ca sensitivity of CaM remained to be elucidated.

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Cystathionine β-synthase (CBS) catalyzes the condensation of l-serine and l-homocysteine to give l-cystathionine in the transsulfuration pathway. Recently, a few O-acetylserine (l-OAS)-dependent CBSs (OCBSs) have been found in bacteria that can exclusively function with l-OAS. CBS from Toxoplasma gondii (TgCBS) can efficiently use both l-serine and l-OAS to form l-cystathionine.

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Cystathionine γ-lyase (CGL) is a PLP-dependent enzyme that catalyzes the last step of the reverse transsulfuration route for endogenous cysteine biosynthesis. The canonical CGL-catalyzed process consists of an α,γ-elimination reaction that breaks down cystathionine into cysteine, α-ketobutyrate, and ammonia. In some species, the enzyme can alternatively use cysteine as a substrate, resulting in the production of hydrogen sulfide (H S).

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Primary Hyperoxaluria Type 1 (PH1) is a rare autosomal disease caused by mutations in AGXT that lead to the deficiency of alanine:glyoxylate aminotransferase (AGT). AGT is a liver pyridoxal 5'-phosphate (PLP)-dependent enzyme that detoxifies glyoxylate inside peroxisomes. The lack of AGT activity results in a build-up of glyoxylate that is oxidized to oxalate, then culminating in hyperoxaluria often leading to kidney failure.

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  • * Two cyclophilin isoforms, TgCyp23 and TgCyp18.4, were studied; TgCyp23 has high activity and strong affinity for CsA, while TgCyp18.4 has lower activity and sensitivity.
  • * The structure of the TgCyp23:CsA complex was determined, revealing differences in their CsA-binding sites, indicating that these cyclophilins might serve different purposes in the parasite's biology.
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Centrins are calcium (Ca)-binding proteins that are involved in many cellular functions including centrosome regulation. A known cellular target of centrins is SFI1, a large centrosomal protein containing multiple repeats that represent centrin-binding motifs. Recently, a protein homologous to yeast and mammalian SFI1, denominated TgSFI1, which shares SFI1-repeat organization, was shown to colocalize at centrosomes with centrin 1 from (TgCEN1).

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Cystathionine beta-synthase (CBS) is a key regulator of homocysteine metabolism. Although eukaryotic CBS have a similar domain architecture with a catalytic core and a C-terminal Bateman module, their regulation varies widely across phyla. In human CBS (HsCBS), the C-terminus has an autoinhibitory effect by acting as a cap that avoids the entry of substrates into the catalytic site.

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Centrins are a family of small, EF hand-containing proteins that are found in all eukaryotes and are often complexed with centrosome-related structures. Since their discovery, centrins have attracted increasing interest due to their multiple, diverse cellular functions. Centrins are similar to calmodulin (CaM) in size, structure and domain organization, although in contrast to CaM, the majority of centrins possess at least one calcium (Ca) binding site that is non-functional, thus displaying large variance in Ca sensing abilities that could support their functional versatility.

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Cysteine plays a major role in the redox homeostasis and antioxidative defense mechanisms of many parasites of the phylum Apicomplexa. Of relevance to human health is , the causative agent of toxoplasmosis. A major route of cysteine biosynthesis in this parasite is the reverse transsulfuration pathway involving two key enzymes cystathionine β-synthase (CBS) and cystathionine γ-lyase (CGL).

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Centrins are conserved calcium (Ca2+)-binding proteins typically associated with centrosomes that have been implicated in several biological processes. In Toxoplasma gondii, a parasite that causes toxoplasmosis, three centrin isoforms have been recognized. We have recently characterized the metal binding and structural features of isoform 1 (TgCEN1), demonstrating that it possesses properties consistent with a role as a Ca2+ sensor and displays a Ca2+-dependent tendency to self-assemble.

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  • * A retrospective study in France from 2014 to 2017 reviewed 760 febrile neutropenia cases, identifying 310 documented BSIs with low prevalence of MDR bacteria (only 2.9%) and no deaths related to these infections.
  • * The findings suggest that a 48-hour step-down approach to antibiotic therapy is effective, supported by parental and nursing efforts to minimize infection risks and reduce instances of staphylococcal infections.
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Non-symbiotic hemoglobins AHb1 and AHb2 from are hexacoordinate heme-proteins that likely have different biological roles, in view of diverse tissue localization, expression pattern, and ligand binding properties. Herein, we expand upon previous biophysical studies on these isoforms, focusing on their oligomeric states and circular dichroism (CD) characteristics. We found that AHb1 exists in solution in a concentration-dependent monomer-dimer equilibrium, while AHb2 is present only as a monomer.

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Cystathionine β-synthase (CBS) catalyzes the condensation of serine and homocysteine to water and cystathionine, which is then hydrolyzed to cysteine, α-ketobutyrate and ammonia by cystathionine γ-lyase (CGL) in the reverse transsulfuration pathway. The protozoan parasite Toxoplasma gondii, the causative agent of toxoplasmosis, includes both CBS and CGL enzymes. We have recently reported that the putative T.

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Primary Hyperoxaluria type I (PH1) is a rare disease caused by mutations in the AGXT gene encoding alanine:glyoxylate aminotransferase (AGT), a liver enzyme involved in the detoxification of glyoxylate, the failure of which results in accumulation of oxalate and kidney stones formation. The role of protein misfolding in the AGT deficit caused by most PH1-causing mutations is increasingly being recognized. In addition, the genetic background in which a mutation occurs is emerging as a critical risk factor for disease onset and/or severity.

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Centrins are calcium (Ca)-binding proteins that have been implicated in several regulatory functions. In the protozoan parasite , the causative agent of toxoplasmosis, three isoforms of centrin have been identified. While increasing information is now available that links the function of centrins with defined parasite biological processes, knowledge is still limited on the metal-binding and structural properties of these proteins.

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Arabidopsis centrin 2, also known as calmodulin-like protein 19 (CML19), is a member of the EF-hand superfamily of calcium (Ca2+)-binding proteins. In addition to the notion that CML19 interacts with the nucleotide excision repair protein RAD4, CML19 was suggested to be a component of the transcription export complex 2 (TREX-2) by interacting with SAC3B. However, the molecular determinants of this interaction have remained largely unknown.

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Studies of the primers that were designed to detect New World Leishmania were systematically reviewed to report the characteristics of each target, detection limit, specificity of the primers designed and diagnostic sensibility. The papers identified in the databases PubMed and Web of Science involved 50 studies. Minicircle is the most applied target in molecular research for diagnosis, due to its high sensitivity in detecting Leishmania in different clinical samples, a characteristic that can be partially attributed to the higher number of copies of the minicircle per cell.

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Background: Ependymoma is the most frequent spinal tumor in adults but it is rather uncommon in children. The aim of the present study was to retrospectively summarize the clinical and therapeutic experience in the treatment of pediatric spinal ependymomas in France.

Methods: In the present retrospective multicenter study, data from patients aged <18 years who had been treated from 2000 to 2010 for spinal ependymomas were collected.

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Oxalate decarboxylase (OxDC) from Bacillus subtilis is a Mn-dependent hexameric enzyme that converts oxalate to carbon dioxide and formate. OxDC has greatly attracted the interest of the scientific community, mainly due to its biotechnological and medical applications in particular for the treatment of hyperoxaluria, a group of pathologic conditions caused by oxalate accumulation. The enzyme has an acidic optimum pH, but most of its applications involve processes occurring at neutral pH.

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Primary hyperoxalurias (PHs) are rare inherited disorders of liver glyoxylate metabolism, characterized by the abnormal production of endogenous oxalate, a metabolic end-product that is eliminated by urine. The main symptoms are related to the precipitation of calcium oxalate crystals in the urinary tract with progressive renal damage and, in the most severe form named Primary Hyperoxaluria Type I (PH1), to systemic oxalosis. The therapies currently available for PH are either poorly effective, because they address the symptoms and not the causes of the disease, or highly invasive.

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Leishmaniases are classified as tegumentary leishmaniasis (TL) and visceral leishmaniasis (VL). Brazil is among the countries with the highest number of TL and VL cases. This study was undertaken to standardize the multiplex polymerase chain reaction (PCR) for the detection of the genus Leishmania in sandflies of endemic regions, on islands in the Upper Paraná River, northwestern Paraná.

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