[Experimental investigation of the efficacy of pirfenidone in prevention of ostium cicatricial closure after dacryocystorhinostomy]. / Eksperimental'noe obosnovanie effektivnosti pirfenidona v predotvrashchenii rubtsovogo zarashcheniya iskusstvennogo soust'ya posle dakriotsistorinostomii.

One of the main reasons of failure of dacryocystorhinostomy (DCR) is cicatricial closure of the ostium. Finding a way to prevent this outcome remains one of the leading aims of research in dacryology. The effectiveness of the most widespread methods is often considered contradictory by various researchers. Pirfenidone is a small-molecule agent that demonstrated good antifibrotic effect and low toxicity in previous in vitro research. There haven't been any in vivo studies of its intraoperative use in DCR.Purpose - to determine the in vivo efficacy of pirfenidone in prevention of ostium cicatricial closure following dacryocystorhinostomy in an animal experiment. MATERIAL AND METHODS: The study was conducted on 18 Chinchilla rabbits. They were divided into 3 groups and each animal underwent modified dacryocystorhinostomy. On the final stage of surgery rabbits of group 1 were injected 1 ml of 0.15 mg/ml pirfenidone solution, rabbits of group 2 - 0.3 mg/ml pirfenidone solution. No injections were performed in group 3. Animals were terminated on days 7 (6 rabbits), 14 (6 rabbits) and 28 (6 rabbits) following surgery. Lacrimal stoma patency was evaluated in vivo by irrigation, and morphologically postmortem. Tissue samples obtained from the stoma area were examined histologically for signs of fibrosis. RESULTS: Failure of dacryocystorhinostomy was observed in 4 out of 18 cases: all rabbits of group 3 terminated on days 14 and 28. The most pronounced morphological signs of fibrosis were also noted in group 3. No topical or systemic adverse effects of the medication were observed in groups 1 and 2. CONCLUSION: Pirfenidone demonstrated high antifibrotic efficacy and low toxicity in experimental dacrycystorhinostomy in rabbits. These results provide grounds for further research into the use of pirfenidone in dacrycystorhinostomy.

[The nasal mucosa and outcomes of dacryocystorhinostomy]. / Sostoianie slizistoi obolochki polosti nosa i rezul'taty dakriotsistorinostomii.

OBJECTIVE: To investigate the impact of the nasal mucosa on the outcomes of dacryocystorhinostomy on the basis of morphologic findings. MATERIAL AND METHODS: The investigation enrolled 73 patients who had undergone endonasal endoscopic dacryocystorhinostomy. Nasal mucosal biopsies were intraoperatively taken from all the patients. The obtained samples were subjected to standard histological examination, as well as to immunohistochemical study using an anti-alpha-smooth muscle actin antibody. To determine the intensity of inflammation in the tissue sample, a chronic inflammation score was calculated. The cell elements positively stained with α-smooth muscle actin were estimated using a semi-automatic method. The patients were divided into groups in accordance with the outcome of surgical treatment after 6 months. RESULTS: An unfavorable outcome of dacryocystorhinostomy was observed in 10 (13.7%) patients. The samples obtained from the patients showed a higher chronic inflammation score (8.33%) and a larger number of the cell elements positively stained with α-smooth muscle actin (6026.38±1944.29). The correlation between the outcome of surgical intervention and the quantitative characteristics of myofibroblasts was statistically significant (p<0.05). CONCLUSION: These studies suggest that there is a direct correlation of the efficiency of endonasal endoscopic dacryocystorhinostomy with the presence and degree of chronic nasal mucosal inflammation at baseline.

[Influence of fibrosis mediators on the outcomes of endoscopic endonasal dacryocystorhinostomy]. / Vliianie mediatorov fibroza na rezul'taty éndonazal'noi éndoskopicheskoi dakriotsistorinostomii.

INTRODUCTION: Fibrosis is the most important pathologic condition involved in undesirable outcomes of dacryocystorhinostomy. A number of biochemical factors are currently known to have an effect on wound healing by promoting excessive scarring. Isoforms of transforming growth factor ß (TGF-ß1) are considered the 'main' pro-fibrotic factor, but wound healing is also affected by other cytokines such as connective tissue growth factor (CTGF), which stimulates fibrosis, and fibroblast growth factor (FGF-2), which acts as antagonist to it. PURPOSE: To investigate correlations between endoscopic endonasal dacryocystorhinostomy outcomes and certain mediators of fibrosis. MATERIAL AND METHODS: The study included 45 cases of endoscopic endonasal dacryocystorhinostomy. The patients were grouped according to surgery outcome: patients with unsuccessful surgical treatment were assigned to group 1 (n=10); patients with successful surgical treatment - to group 2 (n=34). One patient was excluded from the study. Full-layer biopsy specimen were taken from patients' nasal mucosa before the surgery. TGF-ß1, TGF-ß2, TGF-ß3, CTGF, FGF-2 concentrations were evaluated using ELISA and normalized by total protein concentration. RESULTS: Surgical failure was observed in 10 cases (22.72%). CTGF concentration was significantly correlated with negative outcome (p<0.05) and was elevated in most specimen obtained from group 1. No significant correlation was noted between the concentrations of other evaluated cytokines in nasal mucosa specimens and the surgical outcome. CONCLUSION: The study found a correlation between CTGF concentration in nasal mucosa and dacryocystorhinostomy outcome, which supports the hypothesis suggested by several authors linking dacryocystorhinostomy failure with chronic inflammation in nasal mucosa.

Gonadotropins and the timing of progesterone-induced meiotic maturation of Xenopus laevis oocytes.

Isolated oocytes from 30 unstimulated Xenopus laevis females required from 2.50 +/- 0.13 to 14.59 +/- 0.77 hr after progesterone exposure for the first 50% of each group to complete meiotic maturation. Injecting 8 females with an amount of hCG not causing ovulation (25 micrograms, 96 IU) lowered oocyte maturation times by 45-83%. An enzyme-linked immunosorbent assay (ELISA) of the blood of 18 unstimulated animals found a constituent which bound to anti-hCG in amounts (equivalent to 0-1.03 micrograms/ml hCG) that had a direct relationship to the rates of GVBD in oocytes. Preincubation of manually isolated follicles in 0.25-1.25 micrograms/ml hCG shortens oocyte maturation times by 18-50% in a direct, nonlinear fashion and this priming effect is reversed when hCG is withdrawn. The action of gonadotropins in facilitating germinal vesicle breakdown (GVBD) mimics the previously reported priming effect produced by preincubation of oocytes in subthreshold levels of progesterone. Evidence suggests that individual variation in the time course of progesterone-induced meiotic maturation of amphibian oocytes is the result of priming differences caused by the action on follicle cells of fluctuating blood levels of an LH-like hormone.