O comportamento de paracetamol durante a sua oxidação eletrocatalítica sobre poli(azul da anilina) e a sua descrição matemática / Paracetamol behavior during the electrocatalytic oxidation of poly (aniline blue) and its mathematical description

A oxidação eletrocatalítica de paracetamol, acompanhada ou não pela eletropolimerização do próprio, sobre poli(azul da anilina) foi descrita matematicamente (usando a teoria de estabilidade linear e análise de bifurcações). Para o comportamento do composto foi sugerido o mecanismo que concorda com os dados experimentais e com os cálculos teóricos. Foi investigada também a dependência do desempenho do polímero e do comportamento do composto do pH.

The electrocatalytic paracetamol oxidation over poly(aniline blue), accompanied or not by its electropolymerization, has been described mathematically (using the linear stability theory and bifurcation analysis). For the compound' s behavior a mechanism, according with the experimental data and theoretical calculations, has been suggested. Also the pH-dependence of the work of the polymer and the compound' s behavior has been investigated.

The utility of sperm DNA damage assay using toluidine blue and aniline blue staining in routine semen analysis / 대한생식의학회지

OBJECTIVE: The aim of the present study was to examine the relationship among male age, strict morphology, and sperm chromatin structure and condensation. METHODS: Sperm samples from a total of 100 men underwent semen analysis, and sperm chromatin structure and condensation were assessed with toluidine blue (TB) and aniline blue (AB) tests. RESULTS: Prevalence of strict morphology of less than 4%, and abnormal sperm chromatin structure and condensation did not show any statistically significant differences according to male age (p=0.605, p=0.235, and p=0.080). No significant correlation was demonstrated among age of male partners, strict morphology, and abnormal sperm chromatin structure using TB and AB tests. However, abnormal sperm chromatin condensation was positively associated with sperm chromatin structure (r=0.594, p=0.000) and showed negative correlation with strict morphology (r=-0.219, p=0.029). CONCLUSION: The tests for sperm chromatin condensation showed a significant association with strict morphology. Further study is needed to elucidate the relationship between clinical outcome and sperm chromatin tests.

Efficacy of testicular sperm chromatin condensation assay using aniline blue-eosin staining in the IVF-ET cycle / 대한생식의학회지

OBJECTIVE: This study was performed to evaluate testicular sperm chromatin condensation using aniline blue-eosin (AB-E) staining and its effects on IVF-ET. METHODS: Chromatin condensation was analyzed using AB-E staining in 27 cases of testicular sperm extraction. There were 19 cases of obstructive azoospermia (OA) and 8 cases of non-obstructive azoospermia (NOA) in IVF-ET. Mature sperm heads were stained red-pink whereas immature sperm heads were stained dark blue. The percentage of sperm chromatin condensation was calculated from the ratio of the number of red-pink sperm to the total number of sperm analyzed. RESULTS: The overall percentages of chromatin condensation in OA and NOA were 31.1+/-11.2% and 26.3+/-14.4%, respectively. The fertilization rate was significant higher in OA than NOA (p<0.05); however, the rates of good embryos and clinical pregnancy did not show statistical differences. In OA and NOA, statistical differences were not observed in the rate of chromatin condensation, fertilization, good embryos, and clinical pregnancy between the pregnant group and non-pregnant group. CONCLUSION: Chromatin condensation is less stable than OA and showed a low fertilization rate in NOA. While there were no significant differences in chromatin condensation results between NOA and OA, we propose that a pattern of decreased chromatin condensation in NOA is one of the factors of low fertilization results requiring further study.

Efficacy of the Aniline Blue-eosin Staining Method for Testicular Sperm Chromatin Condensation Assay in Azoospermia / 대한남성과학회지

PURPOSE: This study was performed to evaluate chromatin condensation of morphologically mature sperm using a modified aniline blue-eosin (AB-E) staining method in azoospermia. MATERIALS AND METHODS: Chromatin condensation was analyzed using an AB-E staining method in 61 cases (50 patients) of TESE or testicular biopsy with the patient's own sperm. Obstructive azoospermia (OA) was present in 48 cases in 39 patients and non-obstructive azoospermia (NOA) was present in 13 cases in 11 patients, respectively. Immature sperm heads were stained dark blue, whereas mature sperm were stained red-pink by the eosin. The percentage of sperm chromatin condensation was calculated from the ratio of the number of red-pink sperm to the total number of sperm analyzed. RESULTS: The percentage of chromatin maturity was 37.7% vs. 30.3% in OA and NOA, respectively, of the total sperm cell count. The maturity of fresh testicular sperm was 38.3% and 36.3% in OA and NOA, respectively. Also, the maturity of thawed testicular sperm was 34.5% and 10.3% (p<0.05) in OA and NOA, respectively. The maturity of fresh and thawed testicular sperm was 36.3% and 10.3% (p<0.05), respectively, in NOA. These results suggest that chromatin condensation is less stable in sperm of NOA and freezing and thawing procedures may impair sperm chromatin condensation. CONCLUSIONS: In our results, the aniline blue-eosin staining method improved the visualization of excessive histones in sperm and the diagnosis of sperm immaturity in morphologically normal testicular sperm. We found that AB-E staining method can be an effective method for analyzing testicular sperm chromatin condensation in azoospermia.

Hypo-osmotic swelling test as a predictor for nuclear maturity of sperms assessed by aniline blue staining / 대한산부인과학회잡지

OBJECTIVE: Many cases of fertilization failure after ICSI is attributed to decondensation defect of sperm head, therefore, selection of sperm with well-condensed, fully-matured nucleus is critical for successful fertilization. During mammalian spermiogenesis, replacement of the somatic histones by protamines allows normal sperm nuclear condensation. The degree of condensation can be shown with the aid of acidic aniline blue staining, which is able to discriminate between lysine-rich histones and arginine- or cysteine-rich protamines. The objective of this study was to investigate the possible relation between nuclear maturity of human sperm and hypo-osmotic swelling patterns. Hypo-osmotic swelling test is very simple and convenient test to measure functional integrity of human sperm membrane, and each already tested sperms can be used for fertilization. METHODS: For assessment of sperm nuclear maturity, aniline blue staining was performed on the slides, already undergone hypo-osmotic swelling test in 5 subfertile patients with abnormal semen parameters and 8 fertile donors. After 3 hours swim-up, these procedures were repeated in each cases. RESULTS: Sperms with negative aniline blue were significantly increased after swim-up in each group. There was a significant increase in the proportion of negative aniline blue in sperms with swelling patterns(e+f+g) compared to sperms with non-swelling patterns(a), except swim-up group in subfertile patients. CONCLUSION: Choosing the swelling patterns, rather than non-swelling sperms after hypo-osmotic test may be beneficial for the selection of sperms with well-condensed, mature nucleus and intact membrane.