Changes in β-giardin sequence of <Emphasis Type="Italic">Giardia intestinalis</Emphasis> sensitive and resistant to albendazole strains

Giardia intestinalis can develop resistance to albendazole, although the molecular mechanism is not understood. The aim of this study was to investigate the differences and permanent mutation in the β-giardin gene of G. intestinalis strains: sensitive, resistant, or recovered-resistance to albendazole. The β-giardin gene was amplified by nested polymerase chain reaction. The IC₅₀ values varied from 0.29 to 0.38 μg/mL for strains sensitive to albendazole. For resistant strains, the IC₅₀ range was 1.31–2.12 μg/mL. Recovered-sensitivity albendazole strains’ IC₅₀ values were 0.33–0.49 μg/mL, and for strains with recovered-resistance, the IC₅₀ was 1.42–2.74 μg/mL. β-giardin amplicon (720 bp) was sequenced and analysis sequence revealed several amino acid mutations from resistant and recovered-sensitive strains of G. intestinalis. Most of the mutations were located in the ROD domain of β-giardin with a change from the sequence “TIARERA” in sensitive strains instead “IDRPRE” in resistant strains. A comparative sequence analysis in resistant, recovered-sensitive, and resistant-recovered strains revealed permanent mutation. This is the first report of combinatorial serine–proline–arginine repeats in the ROD domain of β-giardin, whereas such repeats have been reported previously in the HEAD domain of SF-assemblin proteins. This is the first time that the resistance to albendazole correlates with genetics but it is not necessarily caused by mutations in the β-giardin gene of G. intestinalis.     

Do you know this syndrome?

Noonan Syndrome is one of the most common genetic syndromes and also an important differential diagnosis in children presenting with syndromic facies similar to Turner''s syndrome phenotype. This syndrome is characterized by facial dysmorphism, congenital heart defects, short stature and also a wide phenotypic variation. This article discusses the case of a 10 year-old patient with Noonan syndrome that presented typical facies, cardiac defects (pulmonary dilatation and mitral regurgitation), dental malocclusion, micrognatism, short stature and a certain degree of learning disability.     

Drug-induced acne and rose pearl: similarities

Drug-induced acne is a common skin condition whose classic symptoms can be similar to a rose pearl, as in the case of a male patient presenting with this condition after excessive use of a cream containing corticosteroids.     

Interpretation of anthropometric indices in children in Arandas,Jalisco, Mexico

OBJECTIVE: To assess the nutritional status of children attending the Instituto Alte?o para el Desarrollo de Jalisco (Highlands Institute for Development of Jalisco State, Inadej) in Arandas, Jalisco and to discuss the classification criteria of infant malnutrition in Mexico. MATERIAL AND METHODS: A cross-sectional study was conducted in 775 children aged between twelve and one hundred and twenty months, who attended Inadej, including 432 children recently registered in INADEJ. Measurements included weight/age, height/age, and weight/height indices. The prevalence of malnutrition was compared using the WHO's criteria and the Mexican Official Norm Classification (NOM-SSA) criteria. The weight/age, height/age and weight/height indices were compared using the chi-squared test. RESULTS: Parents' schooling level was low (mean = 3.6 years); the mean family income was U.S. $198.00 dollars per month, with each family member receiving 0.56 dollars per day for three daily meals. The prevalence of malnutrition was significantly higher with any of the three indices when using the NOM-SSA criteria, as compared to the WHO criteria (weight/age 91.7 vs. 30.9%; height/age 66.9 vs 17.3%; and weight/height 62.5 vs. 9.5%, respectively). CONCLUSIONS: The weight/age index and the NOM-SSA criteria overestimate the prevalence of malnutrition and are not able to tell apart children with familial small size, nor those with acute and/or chronic or past malnutrition. The WHO criteria were found to be more useful; the weight/height (recent malnutrition) and height/age (chronic malnutrition) indices should be used for international comparisons. The English version of this paper is available at: http://www.insp.mx/salud/index.html.