Publications by authors named "Victoria Parera"
This study highlights , a native high-Andean species, as a potential candidate for the phytoremediation of soils contaminated with Cd and Hg. In this work, a semi-hydronic assay with different doses of Cd (3, 4.5, and 6 mg L) and Hg (0.
View Article and Find Full Text PDFThe Multidrug Resistance protein (, ) is involved in the transport of xenobiotics and antiretroviral drugs. Some variants of the gene are of clinical importance; among them, exon 12 (c.1236C>T, rs1128503), 21 (c.
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- Acute Hepatic Porphyrias (AHPs) are serious conditions causing neurological and abdominal symptoms due to issues in heme metabolism, with two main theories suggesting oxidative stress causes nerve damage.
- A study in Argentina examined families with Acute Intermittent Porphyria and Variegate Porphyria, focusing on clinical and biochemical factors and the link between porphyric attacks and oxidative stress.
- The research found no significant differences in oxidative stress or homocysteine levels between affected individuals and healthy controls, indicating that these markers may not be reliable indicators of neurological dysfunction in AHPs.
Article Synopsis
- In Argentina, porphyria cutanea tarda (PCT) is linked with HIV infection, but the relationship with HIV and antiretroviral therapy remains unclear.
- The study examines specific genetic variants that influence drug metabolism and their potential role in the onset of PCT among HIV-infected patients.
- Findings show that certain gene variants are more frequent in PCT patients, suggesting that genetics, along with antiretroviral therapy, may contribute to the development of PCT in those with HIV.
Background/aims: The porphyrias are genetically heterogeneous diseases, and each mutation is exclusive to one or two families. Among the mutations responsible for variegate porphyria in our country, c.1042_1043insT stands out, since it was described only in Argentina and is present in about 40% of genetically diagnosed families.
View Article and Find Full Text PDFPorphyrias are a group of metabolic diseases that arise from deficiencies in the heme biosynthetic pathway. A partial deficiency in hydroxymethylbilane synthase (HMBS) produces a hepatic disorder named Acute Intermittent Porphyria (AIP); the acute porphyria is more frequent in Argentina. In this paper we review the results obtained for 101 Argentinean AIP families and 6 AIP families from foreign neighbour countries studied at molecular level at Centro de Investigaciones sobre Porfirinas y Porfirias (CIPYP).
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- Porphyrias are metabolic diseases impacting the skin and nervous system, with a case study of three patients diagnosed with variegate porphyria in 2008 revealing new mutations in the protoporphyrinogen oxidase gene.
- The identified mutations (c.338+3insT, c.807G>A, and c.808-1G>C) were suspected to affect splicing; RT-PCR tests indicated normal or no mRNA production, suggesting possible degradation of the altered transcripts.
- Minigene tests confirmed that these mutations cause exon skipping, which likely results in mRNA degradation and underscores their role in triggering the disease by disrupting normal splicing pathways.
A partial deficiency in protoporphyrinogen oxidase (PPOX) produces the acute/cutaneous (or mixed) variegate porphyria (VP), the third most frequent porphyria in Argentina. This autosomal dominant disorder is clinically characterized by skin lesions and/or acute neurovisceral attacks. The precise diagnosis of patients with a symptomatic VP is essential to provide accurate treatment.
View Article and Find Full Text PDFPorphyria cutanea tarda (PCT) is caused by decreased activity of uroporphyrinogen decarboxylase (UROD) in the liver. The disease usually occurs in adulthood and is characterized by cutaneous photosensitivity, hyperpigmentation, skin fragility and hypertrichosis, due to the accumulation of porphyrins produced by oxidation of uroporphyrinogen and other highly carboxylated porphyrinogens overproduced as a result of the enzyme deficiency. PCT is generally sporadic, but about 20-30% of patients have familial-PCT (F-PCT) which is associated with heterozygosity of mutations in the UROD gene.
View Article and Find Full Text PDFErythropoietic protoporphyria (EPP) is an inherited disorder of porphyrin metabolism in which decreased activity of ferrochelatase (FECH) leads to accumulation of protoporphyrin IX (PP IX) in red blood cells, plasma, liver, and bile, and increased PP IX excretion in feces. Clinically, EPP is characterized by photosensitivity that begins in early childhood and includes burning, swelling, itching, and painful erythema in sun-exposed areas. Chronic liver disease is an important complication in a minority of EPP patients, and in some cases liver transplantation has been performed.
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- A partial deficiency in Protoporphyrinogen oxidase (PPOX) leads to Variegate Porphyria (VP), a serious condition more common in Argentina that requires precise diagnosis for effective treatment and to prevent severe attacks in asymptomatic relatives.
- Researchers studied 18 new Argentinean VP patients at the molecular level, identifying nine novel and three previously reported mutations in the PPOX gene through DNA amplification and sequencing techniques.
- The newly discovered mutations, including single nucleotide substitutions, small deletions, and an insertion, were linked to a 50% reduction in PPOX activity, which is crucial for understanding the genetic basis of VP and its effects on patients.
The cytochrome P-450 (CYP) isoenzymes, a superfamily of heme proteins which are the terminal oxidases of the mixed function oxidases system, metabolize more than 70% of all clinically approved drugs. The highly polymorphic CYP2D6 isoform metabolizes more than 25% of most common drugs, and the phenotypes of the 70-plus allelic variants range from compromised to excessive enzymatic activity. Porphyrias are a group of inherited or acquired metabolic disorders of heme biosynthesis, due to a specific decrease in the activity of one of the enzymes of the heme pathway.
View Article and Find Full Text PDFBackground: Inherited and environmental factors are implicated in the expression of porphyria cutanea tarda (PCT); the contribution of each factor depends on the population.
Objective: To provide a review of PCT cases diagnosed in Argentina over 24 years and evaluate the role of different precipitating factors in its pathogenesis. Methods Plasma and urinary porphyrin levels and erythrocyte uroporphyrinogen decarboxylase (URO-D) activity were determined.