Assessment of plasma amino acid profile in autism using cation-exchange chromatography with postcolumn derivatization by ninhydrin.

BACKGROUND/AIM: Autism is a heterogeneous neurodevelopmental disorder. This study aimed to assess the clinical significance of amino acid profile assay in autism using cation-exchange chromatography with ninhydrin postcolumn derivatization. MATERIALS AND METHODS: This study included 42 autistic children and 26 apparently healthy children. All participants were subjected to the assay of plasma amino acids (essential, nonessential, and nonstandard) using cation-exchange chromatography with postcolumn derivatization by ninhydrin. RESULTS: The levels of most of the essential amino acids were significantly lower in autistic children than controls. As regards nonessential amino acids, significantly lower levels for plasma cysteine, tyrosine, and serine and significantly higher levels for plasma glutamic acid were recorded in autistic children than controls. Finally, the autistic group demonstrated significantly lower levels of α-aminoadipic acid, carnosine, and ß-alanine and significantly higher levels of hydroxyproline, phosphoserine, ß-amino-isobutyric acid, and ammonia as compared to controls. CONCLUSION: The study revealed that autistic children exhibit distinct alterations in the plasma levels of some amino acids, which can in turn participate in the disease etiology and can be applied as a diagnostic tool for early detection of autism.

Pentraxin-3 in hemodialysis patients: Relationship to comorbidities.

Hemodialysis (HD), despite being the most common treatment modality for endstage renal disease (ESRD), still carries a mortality rate higher than 20-50%/year resulting from various comorbidities. The aim of this study was to measure the plasma level of pentraxin-3 (PTX-3) in patients on maintenance HD and to assess its relationships to comorbidities such as malnutrition and associated comorbid diseases. This case-control study included 50 HD patients, 30 ESRD patients, and 30 healthy controls. HD patients were classified into different subgroups according to the Davies comorbidity index and malnutrition score. Plasma PTX-3 was analyzed by a sandwich ELISA technique. Plasma level of PTX-3 reached its highest levels in HD patients followed by ESRD patients as compared to healthy controls. Moreover, within the different subgroups, the highest levels and the highest odd ratio of PTX-3 were detected in the subgroups having the highest Davies comorbidity index or the highest malnutrition score as compared to the other subgroups. At a cutoff of 0.6 ng/mL, PTX-3 was able to discriminate HD patients with low Davies comorbidity index from those with both medium and high Davies comorbidity index with a diagnostic sensitivity of 92.5% and a diagnostic specificity of 70.0%. Meanwhile, the best cutoff of plasma PTX-3 for discriminating patients with mild malnutrition from severe and moderate malnutrition was 0.6 ng/mL with a diagnostic sensitivity of 90.9% and a diagnostic specificity of 41.2%. In conclusion, PTX-3 appears to be a clinically useful marker for the early identification of patients with renal failure on maintenance HD who are at substantially increased risk of morbidity. These patients may require care and aggressive follow-up in more specialized units and an early referral to a renal transplant center.

Potential correlation between carboxylic acid metabolites in Biomphalaria alexandrina snails after exposure to Schistosoma mansoni infection.

Carboxylic acids play an important role in both aerobic and anaerobic metabolic pathways of both the snail and the parasite. Monitoring the effects of infection by schistosome on Biomphalaria alexandrina carboxylic acids metabolic profiles represents a promising additional source of information about the state of metabolic system. We separated and quantified pyruvic, fumaric, malic, oxalic, and acetic acids using ion-suppression reversed-phase high performance liquid chromatography (HPLC) to detect correlations between these acids in both hemolymph and digestive gland gonad complex (DGG's) samples in a total of 300 B. alexandrina snails (150 infected and 150 controls) at different stages of infection. The results showed that the majority of metabolite pairs did not show significant correlations. However, some high correlations were found between the studied acids within the control group but not in other groups. More striking was the existence of reversed correlations between the same acids at different stages of infection. Some possible explanations of the underlying mechanisms were discussed. Ultimately, however, further data are required for resolving the responsible regulatory events. These findings highlight the potential of metabolomics as a novel approach for fundamental investigations of host-pathogen interactions as well as disease surveillance and control.

Screening for celiac disease in children with dental enamel defects.

Background. Dental enamel defects (DEDs) are seen in celiac disease (CD). Aim was to detect frequency of CD among such patients. Methods. This study included 140 children with DED. They were tested for CD. Gluten-free diet (GFD) was instituted for CD patients. A cohort of 720, age and sex-matched, normal children represented a control group. Both groups were evaluated clinically. Serum calcium, phosphorus, alkaline phosphatase, serum IgA, and tissue transglutaminase (tTG) IgG and IgA types were measured. Results. CD was more diagnosed in patients with DEDs (17.86%) compared to controls (0.97%) (P < 0.0001). Majority of nonceliac patients showed grade 1 DED compared to grades 1, 2, and 3 DED in CD. Five children had DED of deciduous teeth and remaining in permanent ones. After 1 year on GFD, DED improved better in CD compared to nonceliac patients. Gastrointestinal symptoms did not vary between celiac and nonceliac DED patients. Lower serum calcium significantly predicted CD in this cohort. Conclusion. CD is more prevalent among children with DED than in the general population. These DEDs might be the only manifestation of CD; therefore, screening for CD is highly recommended among those patients especially in presence of underweight and hypocalcemia.

Carboxylic acids as biomarkers of Biomphalaria alexandrina snails infected with Schistosoma mansoni.

Biomphalaria alexandrina snails play an indispensable role in transmission of schistosomiasis. Infection rates in field populations of snails are routinely determined by cercarial shedding neglecting prepatent snail infections, because of lack of a suitable method for diagnosis. The present study aimed at separation and quantification of oxalic, malic, acetic, pyruvic, and fumaric acids using ion-suppression reversed-phase high performance liquid chromatography (HPLC) to test the potentiality of these acids to be used as diagnostic and therapeutic biomarkers. The assay was done in both hemolymph and digestive gland-gonad complex (DGG) samples in a total of 300 B. alexandrina snails. All of the studied acids in both the hemolymph and tissue samples except for the fumaric acid in hemolymph appeared to be good diagnostic biomarkers as they provide not only a good discrimination between the infected snails from the control but also between the studied stages of infection from each other. The most sensitive discriminating acid was malic acid in hemolymph samples as it showed the highest F-ratio. Using the Z-score, malic acid was found to be a good potential therapeutic biomarker in the prepatency stage, oxalic acid and acetic acid in the stage of patency, and malic acid and acetic acid at 2 weeks after patency. Quantification of carboxylic acids, using HPLC strategy, was fast, easy, and accurate in prediction of infected and uninfected snails and possibly to detect the stage of infection. It seems also useful for detection of the most suitable acids to be used as drug targets.