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Objectives: To analyze a possible association between glutathione-S-transferase T1 (GSTM1) and/or glutathione-S-transferase M1 (GSTM1) polymorphisms and chronic or aggressive forms of periodontitis in a Caucasian ethnic group. Design and methods: Sixty-nine chronic, 14 aggressive periodontitis and 61 controls, deeply analyzed from a clinical point of view, were studied for their GSTM1 and GSTT1 polymorphisms by allelic specific PCR techniques. As a second control group, 64 blood donors were also included. Results: A significant association was found between GSTM1-null genotype and both chronic and aggressive periodontitis. The aggressive forms were associated with the double null GSTM1 and GSTT1 combination. These results were independent of the patients' age, gender, hygienic habits and smoke (evaluated as tobacco smoking yes/no, cigarettes/day and pack years) as confirmed by multivariate logistic regression analysis. Conclusions: The GSTM1-null variant is statistically associated with the two forms of periodontitis, while the aggressive one also presents a second null variant: GSTT1.

Objective: To determine the type of mutation in a patient with clinical diagnosis of suspected APRT deficiency. Design and methods: A 51-year-old male patient, with a clinical history of two prior episodes of renal colic with urinary stone excretion (reported as uric acid stones in the first episode and as calcium oxalate stones in the second), was admitted to the hospital with severe non-oliguric renal failure (1.06 mmol/L serum creatinine), severe hyponatremia (114 mmol/L Na+), metabolic acidosis (14 mmol/L HCO3−) and uricemia in the normal range. Abnormalities at renal scan and persistency of severe renal failure required to start haemodialysis. Results of renal biopsy prompted us to undertake a biochemical and molecular biological evaluation of the patient for suspected adenine phosphoribosyltransferase (APRT) deficiency. Results: HPLC analysis of serum and urine, for determining purine derivative profile, showed the pathological presence of adenine in both biological fluids (3.57 μmol/L and 7.11 μmol/mmol creatinine in serum and urine, respectively; not detectable in both fluids in healthy controls). APRT assay in a sample of patient hemolysate showed no detectable activity of the enzyme (25.56 ± 9.55 U/L red blood cells in control healthy subjects). Molecular biological analysis of the amplified APRT gene revealed that the patient harboured in exon 3 a homozygous 254 bp deletion–8 bp insertion, previously described only once in a compound heterozygote. Analysis of the patient family showed that heterozygotes for this APRT gene mutation, in spite of a 69% lower APRT enzymatic activity than that of healthy subjects, had no detectable adenine concentrations in both serum and urine. Conclusions: Results of the first patient harbouring the homozygous 254 bp deletion–8 bp insertion of the APRT gene strongly indicated that definitive diagnosis of APRT deficiency (often under or misdiagnosed) would require a combined clinical, biochemical and molecular biological evaluation.

Genetic alterations of the UGT1A1 gene result in Crigler-Najjar (CNS) and Gilbert's (GS)-Syndromes, two autosomal recessive conditions characterized by non-hemolytic unconjugated hyperbilirubinemia. While GS is characterized by mild hyperbilirubinemia, CNS is classified as follows: type I (CNS-I), often associated with irreversible neurological damage due to total deficiency of the UGT1A1 enzyme activity, and type II (CNS-II) where a minimal level of UGT1A1 enzyme activity is maintained. In this context, differential diagnosis of CNS forms needs to be supported by clinical molecular laboratory, in order to correlate biochemical findings to specific genetic mutations. Our paper describes in detail the peculiar clinical feature found in a child with severe neonatal unconjugated hyperbilirubinemia, where DNA analysis showed a new compound heterozygosis determined by two mutations, a known (c.508_510delTTC) and a novel mutation (c.1099C>T) giving a genotype compatible with clinical picture of CNS-II. This novel genotype extends the spectrum of known UGT1A1 mutations, which, in our opinion, could be higher than that currently reported in the literature. Finally, genetic analysis may also be helpful for patients' management.

We report a case of a patient affected by compound heterozygosis for two PK-LR gene mutations: p.R486W (c.1456C>T) and p.M403I (c.1209G>A). Our patient suffered from an initial moderate hemolytic anemia which subsequently evolved into a severe form after mitral prosthetic valve replacement for valve regurgitation. Thereafter, the clinical features evolved into a worsening of anemia, heart failure and pulmonary hypertension, in the absence of valve dysfunction. This clinical picture improved only after an intensive transfusion regimen. This case highlights aspects concerning the intricate balance between the risks and benefits of a mechanical prosthetic valve implant in PK-deficient patients.

Recent studies describe the potential use of biochemical markers in the evaluation of the severity of periodontitis; moreover, patients suffering from periodontitis frequently complain of halitosis (breath malodour), mainly depending on volatile compounds (e.g. hydrogen sulphide, methyl mercaptan, etc.) produced by anaerobic metabolism of oral bacteria and involving sulphur-containing amino acids. In this study, salivary sulphur compounds, such as cysteine, cysteinylglycine and glutathione and some markers of cellular damage (lactate dehydrogenase and aspartate amino transferase), were measured in periodontitis patients and correlated with the periodontal probing pocket's depth.Twenty-two periodontitis patients and forty control subjects were studied for the salivary activities of lactate dehydrogenase and aspartate aminotransferase and cysteine, cysteinylglycine and glutathione concentrations. The periodontitis patients were divided into two subgroups based on the severity of periodontal disease, expressed as median periodontal probing pocket depth (or5 mm). Enzyme activities were measured by using an automated clinical analyzer; cysteine, cysteinylglycine and glutathione concentrations were measured by HPLC equipped with fluorescence detector.A statistically significant increase of the salivary parameters level (cysteine, cysteinylglycine, glutathione, aspartate aminotransferase and lactate dehydrogenase) was found in the patient subgroup with periodontal probing pocket depth5 mm, the salivary cysteine concentrations showing the most significant correlation.Salivary cysteine, a direct precursor of hydrogen sulphide, could be considered reliable markers for the oral tissue damage severity in periodontitis patients.

Background: Vitamin D receptor (VDR) mediates the effects of vitamin D. Our paper evaluates the FokI and BsmI VDR genotypes in 246 Caucasian (Italian from Lazio Region) T1DM patients compared with 246 Caucasian healthy controls, sharing age and gender and regional provenience with the patients. In addition, T1DM patients without complications were compared with those carrying three complications. Methods: Genotyping has been obtained by RFLP-PCR technique. Results: A slight significant association of T1DM with FokI homozygous “ f ” genotype was observed. No association was observed with the presence of multiple complications by a multivariate analysis. Conclusion: T1DM patients showed slightly increased prevalence of “ ff ” VDR genotype.

Background and objectives: The increased need in clinical chemistry laboratories for methods of homocysteine determination, in correlation with cardiovascular diseases and nutritional deficient status, has led to the development of different analytical methods; fluorescent immunoenzymatic assays and, recently, new fully automated spectrophotometric methods are commercially available. In this paper, we compared data obtained from a new enzymatic method for homocysteine assay (Carolina Liquid Chemistries), with data obtained from a HPLC reference method and an immunoenzymatic method (Abbott AxSYM immunoassay). Results: The enzymatic method shows a good correlation with both the HPLC ( Y = −1.3 + 1.02 X ; R 2 = 0.93) and the immunoenzymatic method ( Y = 0.7 + 1.02 X ; R 2 = 0.92), although a bias enhancement was present in some samples. However, the enzymatic method shows a superior analytical feasibility because it needs only common laboratory instruments (UV–visible spectrophotometer) and can be easily adapted to large automatic clinical chemistry analyzers. Moreover, it lowers the laboratory cost of the analysis in comparison to both HPLC and immunoenzymatic methods. Conclusions: The enzymatic Carolina Liquid Chemistries method for homocysteine assay shows acceptable analytical performance and undoubtedly possesses technical and cost advantages.