Francesca Sammartano - Academia.edu (original) (raw)

Papers by Francesca Sammartano

The International Journal of Developmental Biology, 2013

A concise review of the articles about the origin of primordial germ cells (PGCs) in vertebrates ... more A concise review of the articles about the origin of primordial germ cells (PGCs) in vertebrates is provided. Differences among various taxa concerning the origin of PGCs, not easily understandable on the base of traditional knowledge, are pointed out. All those differences can be explained taking into consideration the recent theory of the endoderm as secondary layer. That theory allows us to understand that those differences are only apparent, being related to modifications of stages of the consequent embryogeny, overall, to a different amount of yolk in the egg. Eggs very rich in yolk became meroblastic, and the portion of primordial ectomesenchyme destined to give rise to a part of the mesoderm and the PGCs separates early from the part destined to give rise to the rest of the mesoderm and to the digestive endoderm in order to form the vitelline hypoblast lamina. To this lamina, in contrast to the traditional interpretation, a mesodermal, not endodermal, origin must be attributed. With the misunderstanding regarding the origin of this lamina clarified, all the differences about the origin of PGCs disappears. Furthermore, in taxa where PGCs were considered to be of endodermal origin, they too have a mesodermal origin. Considering that a mesodermal origin of PGCs has been demonstrated in all sponges and cnidarians, as well, a unique, mesodermal origin of germinal cells in all pluricellular animals results.

Thalassemia Reports, 2014

Zoologischer Anzeiger - A Journal of Comparative Zoology, 2005

A relatively new clade, the Ecdysozoa [Aguinaldo et al., 1997. Nature 387, 489-493] was raised ba... more A relatively new clade, the Ecdysozoa [Aguinaldo et al., 1997. Nature 387, 489-493] was raised based on the 18S ribosomal DNA sequences that indicate a close relationship between the moulting phyla (Arthropoda, Tardigrada, Onychophora, Nematoda, Nematomorpha, Kinorhyncha, Lorificera and Priapula), from which the Annelida, with other phyla, are excluded.

Journal of Clinical Periodontology, 1992

This paper reports the treatment of prepubertal periodontitis in a 3year-old girl with Papillon-L... more This paper reports the treatment of prepubertal periodontitis in a 3year-old girl with Papillon-Lefevre Syndrome. Initially, the patient was found to have a myeloperoxidase deficiency and microbiological tests have identified Bacteroides and Fusobacteritttn. in 60% and 25%. respectively of the total number of microbia] flora cultivated. The initial treatment was extration of all the primary teeth with grade 3 mobility, scaling, root planing and daily subgingival irrigation with a 0. 2%n solution of chlorhexidine. Several months before the eruption of the first permanent molars, the rest of the primary teeth were extracted. The patient was treated with daily subgingiva! irrigation of chlorhexidine and weekly professional oral hygiene. At the age 6V; years, the permanent teeth have normal gingiva and crevice depths; microbiological investigation reveals a prevalence of the coccoid forms, and radiographs show no evidence of periodontai pathology.

Journal of Assisted Reproduction and Genetics, 2005

To present the occurrence of a monozygotic bichorionic twinning after the transfer of a single fr... more To present the occurrence of a monozygotic bichorionic twinning after the transfer of a single frozen/thawed embryo has undergone assisted zona hatching (AZH), using a non contact laser. A 33-year-old woman who underwent single frozen embryo replacement (FER). Before transfer, the patient was treated with GnRH agonist and with substitutive therapy (estrogens and progesterone). We are absolutely certain that we are reporting a monozygotic bichorionic pregnancy: a single frozen/thawed embryo was transferred and no concomitant spontaneous conception was possible. Moreover, molecular biology assessment for polymorphisms confirmed clinical findings. The possibility of the occurrence of a monozygotic bichorionic twinning after the transfer of a single frozen/thawed embryo should be borne in mind and its incidence will have to be studied further.

Bolletino di zoologia, 1982

The effect on chiasma frequency and localization of a supernumerary segment (S) found in the M9 c... more The effect on chiasma frequency and localization of a supernumerary segment (S) found in the M9 chromosome in a population of Acrotilus insubricus was analyzed. Whereas chiasma frequency was not significantly increased in the M9/M9S heterozygotes, chiasma localization in the M9 chromosomes was considerably modified: in the M9/M9 individuals single chiasmata were mostly interstitial but they were almost exclusively proximal

Immunological Investigations, 1993

ABSTRACT

Human Reproduction, 2006

BACKGROUND: Our prospective randomized controlled trial was designed to assess whether the use of... more BACKGROUND: Our prospective randomized controlled trial was designed to assess whether the use of GnRH antagonists can improve the success rate of controlled ovarian stimulation (COS)/intrauterine insemination (IUI) treatments, via inhibition of the premature LH rise. METHODS: A total of 104 patients were randomly divided, using a randomization list, into two groups: in group A (n = 52), recombinant FSH (rFSH) was given with GnRH antagonist Cetrorelix, and in group B (n = 52), the patients received rFSH alone in a manner similar to that of group A. The primary outcome measure was clinical pregnancy rate per couple. RESULTS: The pregnancy rate per patient was 53.8% in group A and 30.8% in group B (P = 0.017). The rate of premature LH surge was 7% in group A and 35% in group B (P < 0.0001). A premature luteinization was observed in two cycles of 144 in group A (1.4%) and in 16 cycles of 154 in group B (10.4%) (P = 0.001). The mean values of LH and progesterone were significantly lower in patients receiving GnRH antagonist than in those who did not (3.3 ± 3.3 mIU/ml in group A versus 9.9 ± 7.9 mIU/ml in group B, P < 0.0001, for LH; 1.3 ± 1.1ng/ml versus 2.1 ± 1.9ng/ml for group A and B, respectively, P < 0.0001, for progesterone). CONCLUSION: The use of GnRH antagonist in COS/IUI cycles improves pregnancy rate, preventing the premature LH rise and luteinization.

Human Reproduction, 2009

To understand which genes are really involved in the implantation process, we planned to study th... more To understand which genes are really involved in the implantation process, we planned to study the gene basal expression profile during the window of implantation (WOI) of patients who became pregnant in a subsequent ICSI cycle. Women attending their first ICSI cycle at ANDROS Day Surgery for severe male factor infertility were included in the study. An endometrial biopsy was performed during the WOI, in one of the last two cycles before the ICSI cycle. Forty-seven selected gene profiles were analyzed using Low Density Array technology. Only biopsies from women who subsequently became pregnant were evaluated, to exclude any bias regarding embryo viability and embryo transfer difficulties. Fifteen patients were included in the analysis as they became pregnant after ICSI procedure. Four of 47 selected genes were excluded from the analysis. Of the 43 genes analyzed, only 6 genes (VEGFA, PLA2G2A, ALPL, LIF, NNMT and STC1) showed a statistically uniform expression among patients who subsequently became pregnant. For all the other genes analyzed there were considerable differences in their expression levels amongst women who subsequently became pregnant. Our data suggest that very few genes, which change their expression level during the WOI, show a quantitative homogeneous expression in endometrially-receptive patients. In conclusion, in this study only six genes showed a homogeneous expression, and are probably involved in embryo implantation mechanisms.

Fertility and Sterility, 2004

Objective: To evaluate the predictive value for implantation and pregnancy rates of the number of... more Objective: To evaluate the predictive value for implantation and pregnancy rates of the number of embryos that reach the eight-cell stage with less than 20% fragmentation (good quality embryos) on day 3. Design: Prospective observational study. Setting: Private IVF center. Patient(s): One hundred eighty-nine women undergoing IVF, or intracytoplasmic sperm injection with at least four zygotes, who have had three embryos transferred on day 3. Intervention(s): None. Main Outcome Measure(s): Pregnancy rate and implantation rate. Result(s): All patients (n ϭ 189) had 3 embryos transferred. The patients were divided in five groups according to the number of good quality embryos on day 3 (0, 1, 2, 3, Ͼ3; respectively). For the five groups, the pregnancy rates were 2.9%, 33.3%, 45.5%, 39.4%, and 64.3%; the implantation rates were 2.0%, 17.0%, 20.5%, 19.3%, and 35.7%. No statistically significant differences in pregnancy rate or implantation rate were found for groups 1, 2, and 3 (when 1, 2, or 3 good quality embryos were present). The data were also analyzed after pooling these three groups. A statistically significant difference in pregnancy rate and implantation rate was found for group 0 (no good quality embryos), groups 1, 2, and 3 (1, 2, or 3 good quality embryos), and group Ͼ3 (Ͼ3 good quality embryos).

European Journal of Obstetrics & Gynecology and Reproductive Biology, 2014

To demonstrate that reduction of the cumulative dropout rate (CDR) improves the accuracy of the e... more To demonstrate that reduction of the cumulative dropout rate (CDR) improves the accuracy of the estimate of the cumulative pregnancy rate (CPR) in a set of four intrauterine insemination (IUI) cycles (&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot;four-cycle program&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot;) and increases the total number of pregnancies obtained. Single-centre retrospective observational cohort study of couples who underwent IUI cycles at the Andros Day Surgery Clinic, Palermo, from 1997 to 2011. The main outcome measure was the calculation of the CPR, with life table analysis, firstly by giving the same probability of pregnancy to the dropouts as the patients who continued the treatment (usual method) and secondly by considering this probability null (conservative method). The difference between these two methods was used to verify the accuracy of the estimate. In the 15 years, 924 couples underwent 2956 cycles carried out consecutively in a set of four cycles. The CDR was 16%. The CPR was 31.4% with the usual method and 29.1% with the conservative method. The difference between the two estimates was not significant, indicating a high reliability of the results and a good accuracy of the calculation. Furthermore, maintenance of a low CDR permits improvement of the CPR, as was demonstrated by considering scenarios with worse dropout rates. The &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot;four-cycle program&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot; results in a reduction in the CDR, allowing a better estimation of the CPR, and increases the number of actual pregnancies in IUI. The CPR should become the focus for reporting outcome rates in IUI cycles. Reduction of the dropout rate allows us to give the patient a more reliable and accurate estimate of the pregnancy rate.

European Journal of Epidemiology, 1989

The prevalence of antibodies to Epstein-Barr virus-determined antigens was studied in 17 children... more The prevalence of antibodies to Epstein-Barr virus-determined antigens was studied in 17 children with acute infectious mononucleosis (IM) and in 263 children hospitalized for diseases unrelated to EBV infection. Antibodies against Epstein-Barr viral capsid antigens (VCA) were observed in 173 patients of the control group (66%), but 58 of them (33,5%) had not yet developed antibodies against Epstein-Barr virus-associated nuclear antigen (EBNA). IgM-specific antibodies were not found in any of the children of the control group but were present in all of the 17 patients with IM. The rates of positivity for IgA anti-VCA and IgG anti-early antigen (EA) were similar in all age groups. Anti-viral capsid antigen IgG seropositivity increased to 83% by the age of six years, the mean geometric titre being highest between the ages of 2 and 4 years. Our results suggest that in Sicilian children the primary infection occurs prevalently early in life, in parallel with the occurrence of IM.

Inv Surv Journal, 2009

A low molecular weight (MW) lectin (Paracentrotus lividus small lectin, PlSL) has been found in t... more A low molecular weight (MW) lectin (Paracentrotus lividus small lectin, PlSL) has been found in the sea urchin, Paracentrotus lividus. After gel electrophoresis under denaturing conditions, PlSL exhibits a MW of 13 kDa, while its hemagglutinating activity is Ca 2+ -independent and inhibited by D-Glucose, L-Rhamnose, D-Arabinose, L-Fucose and N-Acetyl-D-glucosamine. Electrophoretic analysis of the coleomic fluid of P. lividus reveals that the presence of PlSL increases following immune challenge with bacteria, whereas it is annulled as a consequence of osmotic stress. Interestingly, two other putative inducible hemagglutinins of an approximate MW of 11 and 32 kDa were retrieved in concomitance with the stress-promoted disappearance of PlSL.

Acta Histochemica, 2005

Massive apoptosis of mesenchymal cells in the septum of the aortico-pulmonary trunk was found in ... more Massive apoptosis of mesenchymal cells in the septum of the aortico-pulmonary trunk was found in mouse fetuses at stage 14.5 dpc. It was associated with the appearance of cavities in the mesenchymal tissue, presumably due to cell loss, a strong reduction in the extent of lectin PNA staining, and the induction of metallothioneins in specialized mesenchymal cells. Cell loss was spatially restricted to an inner area of the septum and was due to a distinct apoptotic pattern of cells, different from that in the heart wall. These events led to a rapid reduction of the aortico-pulmonary septum as occurs during the late stages of heart morphogenesis. It coincided with the migration of other cell types that invaded the cell-depleted septum, and contributed to the histiogenesis of the mature heart.

Italian Journal of Zoology, 2000

Lectin peanut aglutinin histochemistry was used to elucidate histogenesis of septa and valves in ... more Lectin peanut aglutinin histochemistry was used to elucidate histogenesis of septa and valves in mouse heart morphogenesis. Soon after the proliferation of mesenchyme cells in endocardial cushions, lectin peanut aglutinin was found to recognise a glycoprotein of about 65 kDa, which is part of a fibrous network present in the extracellular matrix of endocardial cushions. During a later stage of morphogenesis, both atrioventricular and spiral septa were positive to peanut aglutinin, while interatrial septa were not labelled. At the completion of morphogenesis, septa showed a marked decrease of peanut aglutinin positivity, in concomitance with extended fenestrations of the septal tissue; however, valve leaflets were still positive to the lectin. Thus, lectin peanut aglutinin appears to be a reliable marker of endocardial cushion-derived tissues during valvuloseptal morphogenesis.