Chondroid Syringoma and Eccrine Spiradenoma

Fine needle aspiration cytology (FNAC) is a well established diagnostic tool. However, most clinicians prefer to diagnose suspected skin tumors by excisional biopsy as they are easily accessible and hence benign skin adnexal tumors are rarely encountered on FNAC. There are only a very few case reports describing the fine needle aspiration cytologic features of chondroid syringoma and eccrine spiradenoma for diagnosis. Cases: First case was a 20 year old female who presented with firm,non-tender swelling in the left little finger measuring 1 cm in diameter. Smears showed clusters of round to plasmacytoid cells with moderate to abundant cytoplasm embedded in a chondromyxoid ground substance . Hence, a diagnosis of chondroid syringoma was made. Another case was a 40 year old lady who presented with a painful swelling on the anterior chest wall measuring approximately 0.8 cms in diameter. Smears were moderately cellular with cohesive sheets and clusters of bland cells of three different cell types. Hence, a probable diagnosis of eccrine spiradenoma was made and both the cases were confirmed histologically. Conclusion: Appropriate knowledge of the cytologic features of chondroid syringoma and eccrine spiradenoma helps in providing a definitive diagnosis and correct management of the patient

Deglycosylation of alkylated nucleosides: a molecular orbital study

The glycoside bond in alkylated nucleosides is known to be more stable for $0^6$ -alkylguanosines and $0^4$ - alkylthymines, and less stable for $N^3$ - and $N^7$ -alkylpurine and $O^2$ - alkylpyrimidine nucleosides. These marked differences have been demonstrated through in vitro acidic hydrolysis and in vivo glycosylase repair. This study examines the relative facility of the deglycosylation reaction for various nucleosides through the use of theoretical indices derived from the semiempirical AM1 SCF-MO methodology, which furnish inferences much in consonance with experiment

Mutagenic significance of proton acidities in methylated guanine and thymine bases and deoxynucleosides: A theoretical study

Proton changes have been advanced as being the key molecular basis for the mutagenecity of alkylated DNA bases and nucleosides, leading to questions as to which protons are involved and whether the protic changes are tautomeric shifts or abstractions. This semiempirical molecular orbital study seeks to clarify the issue by examining the various possibilities open for these protic changes in a number of methylated guanines and thymines and their deoxynucleosides. Proton shifts leading to tautomer formation are not predicted as being thermodynamically favourable in most cases. The most feasible proton abstractions are predicted to involve the Watson-Crick protons in all cases, which corroborates Watson-Crick proton loss as providing the key molecular basis for the induction of point mutations. The calculated proton acidities correlate well with experimental data. The gas-phase deprotonation enthalpies for a number of alkylated nucleosides are found to correlate linearly with the solvent-phase pK(a) values. The theoretically calculated enthalpies in a simulated aqueous solvent phase of the deprotonation reactions of various nucleic acid bases are also found to have good linear correlations with experimental pK(a) values. The consensus of these calculations is that O-6-alkyldeoxyguanosines, and O-2- and O-4-alkyldeoxythymidines would be mutagenic while N-7-alkyldeoxyguanosines would not be mutagenic (as experiment indicates). The untested N-3-methyldeoxyguanosine is predicted to be mutagenic. (C) 1997 Elsevier Science B.V

Associations of serum uric acid and SLC2A9 variant with depressive and anxiety disorders: a population-based study

Background: Limited information exists regarding the association between serum uric acid (SUA) and psychiatric disorders. We explored the relationship between SUA and subtypes of major depressive disorder (MDD) and specific anxiety disorders. Additionally, we examined the association of SLC2A9 rs6855911 variant with anxiety disorders. Methods: We conducted a cross-sectional analysis on 3,716 individuals aged 35-66 years previously selected for the population-based CoLaus survey and who agreed to undergo further psychiatric evaluation. SUA was measured using uricase-PAP method. The French translation of the semi-structured Diagnostic Interview for Genetic Studies was used to establish lifetime and current diagnoses of depression and anxiety disorders according to the DSM-IV criteria. Results: Men reported significantly higher levels of SUA compared to women (357±74 μmol/L vs. 263±64 μmol/L). The prevalence of lifetime and current MDD was 44% and 18% respectively while the corresponding estimates for any anxiety disorders were 18% and 10% respectively. A quadratic hockey-stick shaped curve explained the relationship between SUA and social phobia better than a linear trend. However, with regards to the other specific anxiety disorders and other subtypes of MDD, there was no consistent pattern of association. Further analyses using SLC2A9 rs6855911 variant, known to be strongly associated with SUA, supported the quadratic relationship observed between SUA phenotype and social phobia. Conclusions: A quadratic relationship between SUA and social phobia was observed consistent with a protective effect of moderately elevated SUA on social phobia, which disappears at higher concentrations. Further studies are needed to confirm our observations