Value of cytology in papillary condylomatous lesions of the cervix

OBJECTIVE: To determine the value of cytology in detecting mature and immature papillary condylomas of the uterine cervix. STUDY DESIGN: We evaluated 240 cases of plane cervical intraepithelial neoplasia, grade 1 (CIN 1), and 23 papillary condylomas by Pap smear and biopsy and classified histologic sections according to maturity and keratinization. We reevaluated corresponding cytologic smears and identified criteria of low grade squamous lesion (LSIL) and human papillomavirus (HPV) infection. RESULTS: Thirteen (56.5%) papillary lesions were histologically classified as mature, 6 (26%) as immature and 4 (17.3%) as mixed. Fifteen lesions (65.2%) were nonkeratinized, 2 (8.6%) keratinized and 6 (26%) partially keratinized. Corresponding smears were cytologically diagnosed as LSIL (6, 26%), atypical squamous cells of undetermined significance (ASCUS) (7, 30.4%) and negative (10, 43.4%). Careful cytologic review diagnosed only two of the 13 mature lesions; few cytological criteria of LSIL and HPV infection were observed. Koilocytes were seen in just 1 case. Sample limiting factors occurred in 4 cases: 2 cytologically diagnosed as LSIL, 1 asASCUS and 1 as negative for lesion. CONCLUSION: Cytology was not effective in the detection of cervical condyloma acuminatum, independent of limitations in sample adequacy and of the degree of maturity or keratinization of the lesions.     

Essential role of follicle stimulating hormone in the maintenance of caprine preantral follicle viability in vitro

The aims of the present study were to investigate the effects of follicle-stimulating hormone (FSH) on survival, activation and growth of caprine primordial follicles using histological and ultrastructural studies. Pieces of caprine ovarian cortex were cultured for 1 or 7 days in minimum essential medium (MEM - control medium) supplemented with different concentrations of FSH (0, 10, 50 or 100 ng/ml). Small fragments from non-cultured ovarian tissue and from those cultured for 1 or 7 days in a specific medium were processed for classical histology and transmission electron microscopy (TEM). Additionally, effects of FSH on oocyte and follicle diameter of cultured follicles were evaluated. The results showed that the lowest percentage of normal follicles was observed after 7 days of culture in control medium. After 1 day of culture, a higher percentage of growing follicles was observed in the medium supplemented with 50 ng/ml of FSH. In the presence of 10 and 50 ng/ml of FSH, an increase in diameter of both oocyte and follicle on day 7 of culture was observed. TEM showed ultrastructural integrity of follicles after 1 day of culture in MEM and after 7 days in MEM plus 50 ng/ml FSH, but did not confirm the integrity of those follicles cultured for 7 days in MEM. In conclusion, this study demonstrated that FSH at concentration of 50 ng/ml not only maintains the morphological integrity of 7 days cultured caprine preantral follicles, but also stimulate the activation of primordial follicles and the growth of activated follicles.     

Structural analysis of Canavalia maritima and Canavalia gladiata lectins complexed with different dimannosides: new insights into the understanding of the structure-biological activity relationship in legume lectins

Plant lectins, especially those purified from species of the Leguminosae family, represent the best studied group of carbohydrate-binding proteins. The legume lectins from Diocleinae subtribe are highly similar proteins that present significant differences in the potency/efficacy of their biological activities. The structural studies of the interactions between lectins and sugars may clarify the origin of the distinct biological activities observed in this high similar class of proteins. In this way, this work presents a crystallographic study of the ConM and CGL (agglutinins from Canavalia maritima and Canavalia gladiata, respectively) in the following complexes: ConM/CGL:Man(alpha1-2)Man(alpha1-O)Me, ConM/CGL:Man(alpha1-3)Man(alpha1-O)Me and ConM/CGL:Man(alpha1-4)Man(alpha1-O)Me, which crystallized in different conditions and space group from the native proteins. The structures were solved by molecular replacement, presenting satisfactory values for R(factor) and R(free). Comparisons between ConM, CGL and ConA (Canavalia ensiformis lectin) binding mode with the dimannosides in subject, presented different interactions patterns, which may account for a structural explanation of the distincts biological properties observed in the lectins of Diocleinae subtribe.     

Structural and Functional Insight into the Carbohydrate Receptor Binding of F4 Fimbriae-producing Enterotoxigenic Escherichia coli

Enterotoxigenic Escherichia coli (ETEC) strains are important causes of intestinal disease in humans and lead to severe production losses in animal farming. A range of fimbrial adhesins in ETEC strains determines host and tissue tropism. ETEC strains expressing F4 fimbriae are associated with neonatal and post-weaning diarrhea in piglets. Three naturally occurring variants of F4 fimbriae (F4_ab, F4_ac, and F4_ad) exist that differ in the primary sequence of their major adhesive subunit FaeG, and each features a related yet distinct receptor binding profile. Here the x-ray structure of FaeG_ad bound to lactose provides the first structural insight into the receptor specificity and mode of binding by the poly-adhesive F4 fimbriae. A small D′-D″-α1-α2 subdomain grafted on the immunoglobulin-like core of FaeG hosts the carbohydrate binding site. Two short amino acid stretches Phe¹⁵⁰–Glu¹⁵² and Val¹⁶⁶–Glu¹⁷⁰ of FaeG_ad bind the terminal galactose in the lactosyl unit and provide affinity and specificity to the interaction. A hemagglutination-based assay with E. coli expressing mutant F4_ad fimbriae confirmed the elucidated co-complex structure. Interestingly, the crucial D′-α1 loop that borders the FaeG_ad binding site adopts a different conformation in the two other FaeG variants and hints at a heterogeneous binding pocket among the FaeG serotypes.