CO2 laser vaporization for the treatment of vaginal intraepithelial neoplasia: effectiveness and predictive factors for recurrence.

OBJECTIVE: To evaluate the outcome of vaginal intraepithelial neoplasia (VaIN) treatment with CO2 laser vaporization in terms of local recurrence and progression to vaginal carcinoma. Additionally, the authors investigated the predictive factors for first recurrence. MATERIALS AND METHODS: The medical records of all patients treated for VaIN with CO2 laser vaporization at Sant'Anna Hospital in Turin (1995-2012), were retrospectively reviewed. A univariate logistic model was applied to evaluate selected clinical features as predictive factors for recurrence. A multivariate logistic regression analysis was then carried out including significant risk factors after univariate analysis (p < 0.05). RESULTS: The analysis included 285 out of 302 patients. Seventy-one (25%) women relapsed; of these 24 VaIN 1 (22%), 37 VaIN 2 (27%), and ten VaIN 3 (26%). The median time to the first recurrence was 5.2 months (1.4-127.8) for VaIN 1, 6.6 months (1-85.2) for VaIN 2, and 3.6 months (1.2-62) for VaIN 3. Sixty-one out of 71 patients were retreated with CO2 laser vaporization. At the last follow-up visit, 273 (96%) women were free from VaIN. No patients progressed to vaginal carcinoma. The multivariate model showed a higher risk of VaIN recurrence in the case of previous hysterectomy (HR 3.3, 95% CI 1.7-6.3, p < 0.001) and concomitant H-SIL on the Pap smear (HR 1.9, 95% CI 1.2-3.1, p = 0.008). CONCLUSION: CO2 laser vaporization is an effective low impact treatment for VaIN. Despite this, VaIN recur, in particular in cases of previous hysterectomy and concomitant H-SIL on the Pap smear. An intensive follow-up is proposed for women with a high risk of VaIN relapse.

Carbon dioxide laser surgery in colposcopy for cervicovaginal intraepithelial neoplasia treatment. 10 years experience and failure analysis.

CO2 laser vaporisation is an effective method in the treatment of cervico-vaginal pre-invasive lesions. In a case-series of 334 patients no case of invasive neoplasia development were registered at longterm follow-up. The failure rate is comparable to those described with traditional surgical methods and are due to the particular topography of the disease.

Differences in lipid characteristics of undifferentiated and enterocytic-differentiated HT29 human colonic cells.

In this paper we compared several lipid characteristics of the homogenate and the corresponding plasma membrane in undifferentiated and differentiated HT29 human colon cancer cells, using normal human colonic cells as a reference. Electron microscopy showed that HT29 cells were morphologically undifferentiated when cultured in the presence of either glucose or inosine without glucose at early confluency. On the contrary, HT29 cells cultured at late confluency in a glucose-free medium containing inosine or grown in nude mice exhibited an enterocytic differentiation with the presence of tight junctions and an apical brush border. The cell homogenate and the plasma membrane were prepared from each cell type. The study of specific marker enzymes showed the same degree of purity in all plasma membranes, with a highly marked increase of brush border-associated hydrolases (N-aminopeptidase and alkaline phosphatase) only in the organelles isolated from differentiated HT29 and colonic cells. Respective similar increases in the amount of free cholesterol and phospholipid and in the free cholesterol:phospholipid molar ratio were found in the plasma membrane as compared with the homogenate in all HT29 cell types. This ratio, due to an increased phospholipid content in both homogenate and plasma membrane, was lowered in colonic cells. No differences in the phospholipid profile were found between the homogenates of all cell types and the plasma membrane of undifferentiated HT29 cells, with the exception of a decrease of cardiolipin in this organelle. On the contrary, the plasma membrane phospholipid composition was different from that of the corresponding homogenate in differentiated HT29 and colonic cells. The most striking changes were a highly increased sphingomyelin amount and concomitant decreases in phosphatidylethanolamine, phosphatidylserine, and cardiolipin. Moreover, differences in the percentage of phosphatidylcholine plus sphingomyelin as well as in phosphatidylcholine:sphingomyelin, phosphatidylethanolamine, and/or phosphatidylcholine molar ratios were also found. The monounsaturated:polyunsaturated fatty acid ratio in phosphatidylethanolamine was similar in differentiated HT29 and colonic cells and lower than in undifferentiated HT29 cells. A decrease in this latter ratio in phosphatidylcholine was also observed in colonic cells and HT29 cells grown in nude mice. These changes were essentially due to opposite variations in the percentage of palmitoleic acid and those of linoleic and/or arachidonic acids in both phospholipids. Thus, these data indicate that undifferentiated HT29 cells were characterized by the absence of a specific phospholipid composition in their plasma membrane, which is suggested to be related to altered phospholipid sorting. The plasma membrane phospholipid profile reversed essentially to the normal pattern when HT29 cells recovered the ability to differentiate.

Complete amino acid sequence and location of the five disulfide bridges in porcine pancreatic alpha-amylase.

Porcine pancreatic alpha-amylase (1,4-alpha-D-glucan glucanohydrolase EC 3.2.1.1), a single polypeptide chain, contains nine residues of methionine. Eight different fragments resulting from cleavage of this molecule by cyanogen bromide were characterized. The sequences of six of them have previously been reported. Two missing fragments, CN2 (82 residues) and CN3b1 (76 residues) were purified after breaking of the interpeptidic disulfide bridge and their complete sequence as well as that of the previously purified CN1 peptide (102 residues) are reported here. The location of the three disulfide bridges present in these peptides was determined. Ordering of the carboxymethylated cyanogen bromide fragments was carried out by pulse labeling the amylase chain in vivo. The complete sequence of the porcine pancreatic amylase chain (496 residues) and the location of its five disulfide bridges is presented. Comparison with human and mouse pancreatic and salivary alpha-amylases and with rat pancreatic amylase obtained from the corresponding cDNA nucleotidic sequences shows a high degree of homology between mammalian alpha-amylases.

Localization of the two free thiol groups in the porcine pancreatic alpha-amylase I sequence.

Porcine pancreatic alpha-amylase I, a single 496 residue long polypeptide chain, contains 5 disulfide bridges and 2 free -SH groups. The conditions for specific blocking of native amylase either with radioactive N-ethyl maleimide or with labeled iodoacetic acid were determined. Under these conditions 2 moles of blocking reagent are incorporated per mole of amylase. [14C]-S-succinimido amylase was cleaved by CNBr and the resulting peptides were purified. Only one of them the CNBr 2 + 3 peptide (178 residues) was found labeled. Ts1 a 33-residue peptide containing the whole radioactivity was purified from the tryptic digest of this large fragment. After reduction and carboxymethylation Ts1A, (22 residues) was obtained which contains 2 moles of succinyl-Cys and one mole of CM-Cys per mole of peptide. Chymotryptic digestion of Ts1A yielded 2 equally labeled peptides: C1 (16 residues) and C2 (6 residues). Automated sequencing of both peptides and counting of the PTH-amino acids shows that the free cysteines are only 15 residues apart in the sequence.