Biomedical subjects

Antonino Forabosco

Publications and source records attributed to Antonino Forabosco.

15 recordsLinked to original sources

PubMed2007

Determination and stability of sex.

How is the embryonic bipotential gonad regulated to produce either an ovary or a testis? In males, transient early activation of the Y chromosome Sry gene makes both germ cells and soma male. However, in females, available evidence suggests that the process of ovary sex determination may take place independently in the germline and somatic lineages. In addition, in contrast to testis, in ovary somatic cells, female-to-male gonadal sex reversal can occur at times throughout ovary development and maturation. We suggest that a single gene pathway, likely hinging on the Foxl2 transcription factor, both initiates and maintains sex differentiation in somatic cells of the mammalian ovary.

Animals↗

PubMed2005

Foxl2 is required for commitment to ovary differentiation.

Genetic control of female sex differentiation from a bipotential gonad in mammals is poorly understood. We find that mouse XX gonads lacking the forkhead transcription factor Foxl2 form meiotic prophase oocytes, but then activate the genetic program for somatic testis determination. Pivotal Foxl2 action thus represses the male gene pathway at several stages of female gonadal differentiation. This suggests the possible continued involvement of sex-determining genes in maintaining ovarian function throughout female reproductive life.

Animals↗

PubMed2005

Gonadoblastoma in Turner syndrome and Y-chromosome-derived material.

The identification of Y-chromosome material is important in females with Ullrich-Turner syndrome (UTS) due to the risk of developing gonadoblastoma or other gonadal tumors. There is controversy regarding the frequency of the Y-chromosome-derived material and the occurrence of gonadoblastoma in these patients. The aim of our study was to evaluate a large number of patients with UTS, followed before and during the pubertal age for the prevalence of Y-chromosome derived material, the occurrence of gonadoblastoma, and the incidence of possible neoplastic degeneration. An unselected series of 171 patients with UTS (1-34 years old), diagnosed cytogenetically, was studied for Y-chromosome markers (SRY and Y-centromeric DYZ3 repeats). The follow-up was of 2-22 years; 101 of these patients were followed during pubertal age. Y-chromosome material was found in 14 patients (8%): 12 of these were gonadectomized (2.8-25.9 years). A gonadoblastoma was detected in four patients under 16 years of age: in two, Y-material was detected only at molecular analysis (at conventional cytogenetic analysis, one was included in the 45,X group and one in the X + mar group) and one had also an immature teratoma and an endodermal sinus carcinoma. The prevalence of gonadoblastoma in our series of gonadectomized UTS patients with Y-positive material was of 33.3% (4/12). Our data suggest that the age of appearance and the possibility of malignant degeneration of gonadoblastoma can occur early in life. These patients, in particular those with 45,X or a marker chromosome may benefit from molecular screening to detect the presence of Y-chromosome material; PCR is a rapid and inexpensive technique. At the moment, laparoscopy and preventive gonadectomy performed as soon as possible remain the procedures of choice for patients with UTS, when Y-chromosome has been identified, as we are still unable to predict a future malignant evolution of gonadoblastoma.

Adolescent↗

PubMed2005

Mouse ovary developmental RNA and protein markers from gene expression profiling.

To identify genes involved in morphogenetic events during mouse ovary development, we started with microarray analyses of whole organ RNA. Transcripts for 60% of the 15,000 gene NIA panel were detected, and about 2000 were differentially expressed in nascent newborn compared to adult ovary. Highly differentially expressed transcripts included noncoding RNAs and newly detected genes involved in transcription regulation and signal transduction. The phased pattern of newborn mouse ovary differentiation allowed us to (1) extend information on activity and stage specificity of cell type-specific genes; and (2) generate a list of candidate genes involved in primordial follicle formation, including podocalyxin (Podxl), PDGFR-beta, and a follistatin-domain-encoding gene Flst1. Oocyte-specific transcripts included many (e.g., Deltex2, Bicd2, and Zfp37) enriched in growing oocytes, as well as a novel family of untranslated RNA's (RLTR10) that is selectively expressed in early stage follicles. The results indicate that global expression profiling of whole organ RNA provides sensitive first-line information about ovarian histogenesis for which no in vitro cell models are currently available.

Animals↗

PubMed2005

The use of non-physiological conditions to isolate fetal cells from maternal blood.

Fetal cells are always present in maternal blood starting in the first trimester of pregnancy, however a rapid, simple, and consistent procedure for their isolation for prenatal non-invasive genetic investigation is still lacking. Sensitivity and recovery of fetal cells is jeopardized by the minute amount of circulating fetal cells and their loss during the enrichment procedure. We report here a single-step approach to isolate fetal cells from maternal blood which relies on the use of non-physiological conditions to modify cell densities before their separation in a density gradient and in a newly developed cell separation device. Isolated fetal cells have been investigated using cytochemistry, Soret band absorption microscopy, monoclonal antibodies for epsilon- and gamma-chain-Hb, monoclonal antibody for i-antigen, and by fluorescence in situ hybridization (FISH). Fetal cells were always detected in all 105 maternal blood samples investigated and fetal aneuploidies were correctly diagnosed by FISH, in a pilot study of pathological pregnancies, in fetal cells isolated from maternal blood obtained either before or after invasive procedure.

Aneuploidy↗

PubMed2005

Detection of a novel dystrophin gene mutation through carrier analysis performed during prenatal diagnosis in a case with intragenic recombination.

OBJECTIVES: To report a multi-technical approach to Duchenne muscular dystrophy (DMD) mutation testing through carrier analysis, in the prenatal diagnosis of a male foetus without a known mutation segregating in the family and with inconclusive results of linkage analysis. METHODS: Haplotype analysis with the DMD region markers for assigning the carrier status of the mother and for prenatal diagnosis of foetal DNA; semiquantitative multiplex analysis of maternal and foetal DNA for the promoter and for 34 exons of the DMD gene; sequencing analysis of the maternal and foetal DNA for confirmation of the results. RESULTS: Because of an intragenic recombination of the DMD gene in foetal DNA, haplotype analysis gave inconclusive results. Semiquantitative PCR analysis displayed a pattern compatible with a heterozygous exon 60 mutation in the mother's DNA, while foetal DNA showed a normal migration pattern. Sequencing analysis confirmed the presence of a novel 7 base-pair deletion in exon 60 of the DMD gene in the mother and excluded the deletion in the foetus. CONCLUSION: Semiquantitative PCR results allowed the DMD mutation detection in the mother and the exclusion in the foetus, showing its crucial importance in prenatal diagnosis in those cases where linkage analysis is not conclusive.

DNA Mutational Analysis↗

PubMed2004

Foxl2 disruption causes mouse ovarian failure by pervasive blockage of follicle development.

FOXL2 mutations cause gonadal dysgenesis or premature ovarian failure (POF) in women, as well as eyelid/forehead dysmorphology in both sexes (the 'blepharophimosis-ptosis-epicanthus inversus syndrome', BPES). Here we report that mice lacking Foxl2 recapitulate relevant features of human BPES: males and females are small and show distinctive craniofacial morphology with upper eyelids absent. Furthermore, in mice as in humans, sterility is confined to females. Features of Foxl2 null animals point toward a new mechanism of POF, with all major somatic cell lineages failing to develop around growing oocytes from the time of primordial follicle formation. Foxl2 disruption thus provides a model for histogenesis and reproductive competence of the ovary.

Animals↗

PubMed2004

First-trimester prenatal screening for the common 35delG GJB2 mutation causing prelingual deafness.

OBJECTIVE: This study evaluates the prevalence of 35delG GJB2 mutation, the most common genetic mutation causing prelingual deafness, and its screening feasibility and acceptability in pregnant women undergoing first-trimester CVS for chromosomal abnormality investigation. METHODS: Samples were taken from 5786 pregnant women who requested CVS for chromosomal analysis. The samples were split into two aliquots for chromosome and DNA analysis, respectively. The results of foetal karyotyping were provided 7 days after sampling, at which time the fully informed couple decided whether or not to undergo DNA testing. RESULTS: Of the 5449 eligible candidates, 2997 (55.0%) chose to undergo 35delG testing. Among them, 67 proved to be carriers of the mutation, resulting in a prevalence rate of 1:44.7 (2.23%). There were no homozygous foetuses, but two double heterozygous foetuses were found, and in one case the couple chose to terminate the pregnancy. CONCLUSIONS: The results confirm the high frequency of 35delG mutation in the Italian population. The study shows that prenatal screening for GJB2 mutations in pregnant women with no retrospective risk for deafness appears to be feasible and highly acceptable. Consequently, given evidence that early evaluation and treatment significantly improve speech and language skills, as well as social and emotional well-being in affected children, 35delG mutation analysis in pregnant women booking CVS primarily for chromosomal investigation could be considered a useful addition to more comprehensive population screening strategies.

Chorionic Villi Sampling↗

PubMed2004

Growth patterns of human ovarian volume during intrauterine and postnatal organogenesis.

BACKGROUND: Ovarian volumes during pre-pubertal, reproductive or menopausal life in a healthy female have been studied by in vivo and anatomical methods. In contrast, conclusive studies on normal human ovarian volume during intrauterine and postnatal organogenesis, when the folliculogenesis occurs, do not exist. AIM: To assess the growth patterns of ovarian volume during human ovarian definitive histogenesis using morphometric methods. SUBJECTS: Twenty-five left ovaries removed from fetuses, newborns and children with karyotype 46,XX, ranging from 15 to 74 weeks of development. OUTCOME MEASURES: The ovaries were completely cut obtaining serial sections. Ovarian volume was calculated both with the ellipsoid method, using its length, maximum and minimum diameters, and the Cavalieri quantitative morphometric method. The age-related pattern of ovarian volume was studied using linear regression analyses. RESULTS: Ovarian volume calculated with the Cavalieri method increased from 16 mm3 at the 15th week of development to over 300 mm3 at the end of the process, with a 20-fold increase compared to the initial volume. Ovarian volume calculated with the ellipsoid method ranged between 25 to over 380 mm3, with a 15-fold increase. On average, ellipsoidal volume over-estimated the true Cavalieri volume (mean difference -14%, S.D. 29, p=0.014, Student's t-test for paired samples). Linear regression curves were developed to predict ovarian volume at any age. Overall, the approximation was better for Cavalieri volume (approximately, 72% of variance explained by the linear regression) than for ellipsoid volume (59% of explained variance). CONCLUSIONS: During the intrauterine and postnatal organogenesis, the normal growth rate of human ovary was almost linear. The calculation of ovarian volume using Cavalieri method does not depend on assumptions about the organ shape and it appears to be more appropriate.

Female↗

PubMed2004

Aging of oocyte, ovary, and human reproduction.

We review age-related changes in the ovary and their effect on female fertility, with particular emphasis on follicle formation, follicle dynamics, and oocyte quality. The evidence indicates that the developmental processes leading to follicle formation set the rules determining follicle quiescence and growth. This regulatory system is maintained until menopause and is directly affected in at least some models of premature ovarian failure (POF), most strikingly in the Foxl2 mouse knockout, a model of human POF with monogenic etiology (blepharophimosis/ptosis/epicanthus inversus syndrome). Several lines of evidence indicate that if the ovarian germ cell lineage maintains regenerative potential, as recently suggested in the mouse, a role in follicle dynamics for germ stem cells, if any, is likely indirect or secondary. In addition, age-related variations in oocyte quality in animal models suggest that reproductive competence is acquired progressively and might depend on parallel growth and differentiation of follicle cells and stroma. Genomewide analyses of the mouse oocyte transcriptome have begun to be used to systematically investigate the mechanisms of reproductive competence that are altered with aging. Investigative and therapeutic strategies can benefit from considering the role of continuous interactions between follicle cells and oocytes from the beginning of histogenesis to full maturation.

Aging↗

PubMed2003

Noonan-like syndrome with loose anagen hair: a new syndrome?

We present three children with short stature, the same facial phenotype, macrocephaly, enlarged cerebral spinal fluid spaces, short neck with redundant skin, severe GH deficiency, mild psychomotor delay with attention deficit/hyperactivity disorder (ADHD), mild dilatation of the pulmonary root in two of them, and a unique combination of ectodermal abnormalities. Their appearance, not completely typical of Noonan syndrome, the behavioral phenotype, GH deficiency, darkly pigmented and hairless skin, and the unusual aspect of the hair, defined as loose anagen hair syndrome did not fit any known condition. We postulate that these children may represent a distinct, previously unreported syndrome that we would name "Noonan-like syndrome with loose anagen hair".

Adolescent↗

PubMed2003

Position of follicles in normal human ovary during definitive histogenesis.

BACKGROUND: Follicular growth in the mammalian ovary follows a geographically determined pattern, but no exhaustive data about their spatial localization in the cortex of human ovary exists. AIM: The aim of this study is to assess the spatial position of the follicles during human ovarian definitive histogenesis using morphometric methods. SUBJECTS: Ovaries removed from four fetuses, five newborns and one 8-month-old child with 46,XX karyotype was used. OUTCOME MEASURES: The position of the different follicle categories (primordial, primary, secondary and antral) was estimated as percentage distance of the centroid of the follicle from the cortico-medullary boundary. RESULTS: In normal ovaries, during definitive histogenesis, the primordial follicles progressively occupy more peripheral parts of the cortex (on average, 41% of cortical length at 20 weeks of fetal development, 53% at birth, 68% at 8 postnatal months). Primary follicles were crowded in the inner part of the cortex (newborn: 30-40% of cortical length; 8 months: 52% of cortical length). Secondary and antral follicles were sampled in all neonatal specimens and in the 8-month old specimen; they were grouped next to the cortico-medullary boundary. CONCLUSIONS: Ovarian development corresponded to a migration of the maximum crowding of follicles from a position next to the medulla towards a more peripheral location. The control of the primordial follicle assembly, recruitment and development are coordinated by locally produced paracrine factors. The action of these factors seems to follow a negative gradient from the cortex toward the medulla.

Female↗

PubMed2003

Genotype/phenotype correlations of males affected by Simpson-Golabi-Behmel syndrome with GPC3 gene mutations: patient report and review of the literature.

Simpson-Golabi-Behmel syndrome (SGBS) is an X-linked overgrowth syndrome with associated visceral and skeletal anomalies. Deletions or point mutations involving the glypican-3 (GPC3) gene at Xq26 are associated with a relatively milder form of this disorder (SGBS1). GPC3 encodes a putative extracellular proteoglycan, glypican-3, that is inferred to play an important role in growth control in embryonic mesodermal tissues in which it is selectively expressed. It appears to form a complex with insulin-like growth factor-II (IGF-II), and might thereby modulate IGF-II action. We reviewed the clinical findings of all published patients with SGBS1 with GPC3 mutations to confirm the clinical specificity for the SGBS1 phenotype. Moreover, we report on a new patient with a GPC3 deletion and IGF-II evaluation.

DNA↗

PubMed2002

Genes and translocations involved in POF.

Changes at a single autosomal locus and many X-linked loci have been implicated in women with gonadal dysgenesis [premature ovarian failure (POF) with deficits in ovarian follicles]. For the chromosome 3 locus, a forkhead transcription factor gene (FOXL2) has been identified, in which lesions result in decreased follicles by haploinsufficiency. In contrast, sporadic X; autosomal translocations are distributed at many points on the X, but concentrate in a critical region on Xq. The association of the breakpoints with genes involved in ovarian function is thus far weak (in four analyzed cases) and has not been related to pathology in other POF patients. While many more translocations can be analyzed in detail as the human genome sequence is refined, it remains possible that translocations like X monosomy (Turner syndrome) lead to POF not by interrupting specific genes important in ovarian development, but by causing aberrations in pairing or X-inactivation during folliculogenesis. It is noted that the critical region has unusual features, neighboring the X-inactivation center and including an 18 Mb region of very low recombination. These suggest that chromosome dynamics in the region may be sensitive to structural changes, and when modified by translocations might provoke apoptosis at meiotic checkpoints. Choices among models for the etiology of POF should be feasible based on studies of ovarian follicle development and attrition in mouse models. Studies would prominently include gene expression profiling of developmental-specific pathways in nascent ovaries with controlled levels of Foxl2 and interacting proteins, or with defined changes in the X chromosome.

Chromosomes, Human, X↗

PubMedDate not supplied

Morphological observations and morphometric analysis in three human fetuses with bilateral cervical cystic hygroma.

Three human fetuses (crown-rump length, CRL, ranging from 71 to 77 mm), presenting bilateral cervical cystic hygroma were examined. The specimens were cleared and double-stained with alcian blue and alizarin red S for detecting the ossification growth patterns in the vertebral column, ribs, ischium, limbs, and face. Longitudinal measurements of some long bones in the upper (humerus, ulna, radius) and lower (femur, tibia, fibula) limb were taken. The values of both the total length (TL) and the ossified part (OL) of each long bone, as well as the OL/TL per cent ratio were considered. Reference points were located on the mandible, i.e. condylar process (Pcl), coronoid process (Pco), gnathion (GN), gonion (GO), inferior interdental point (IDI) for measuring linear dimensions. All values obtained were related with those relative to a group of fetuses, without any detectable malformation and chromosomal abnormalities, with CRL mean value 75 mm, in order to assess the presence of further anomalies, besides the cystic hygroma, in the three fetuses considered.

Anthropometry↗