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Giuseppe Calabrese

Publications and source records attributed to Giuseppe Calabrese.

17 recordsLinked to original sources

Identification and characterization of different SHOX gene deletions in patients with Leri-Weill dyschondrosteosys by MLPA assay.

Deletions of the SHOX gene (Xp22-Yp11.3) are associated with Leri-Weill dyschondrosteosys (LWD) and idiopathic short stature. It has been estimated that SHOX deletions occur in 1,000-2,000 individuals in the total population, suggesting that this alteration should be investigated in all cases with unexplained short stature. SHOX deletions are currently investigated using fluorescence in situ hybridization (FISH) or molecular analysis of intragenic CA repeats. However, both techniques show some limitations. In the present study, the use of the multiple ligation probe amplification (MLPA) assay for the identification and characterization of SHOX deletions in 15 LWD patients, 3 of which carriers of chromosome abnormalities involving the SHOX gene, is reported. MLPA analysis demonstrated the heterozygous deletion of SHOX in seven patients (46.6%), disclosing the presence of two different proximal breakpoints. In patients with abnormal karyotype, MLPA analysis was able to identify the chromosomal rearrangement, showing, in addition to the SHOX deletions, the gain or loss of other genes mapped on the X and Y chromosomes. Since MLPA analysis can be carried out on a simple buccal swab, avoiding invasive peripheral blood collection, this technique represents a fast, simple and high throughput approach in the screening of SHOX deletions, able to provide more information as compared to FISH and microsatellite analysis.

Abnormalities, Multiple↗

Audiogenic seizure susceptibility is reduced in fragile X knockout mice after introduction of FMR1 transgenes.

The Fmr1 knockout (KO) mouse is characterized by an increased audiogenic seizure (AGS) susceptibility and is considered a good animal model for epilepsy and seizures in the human fragile-X (FRAX) syndrome. Here, we tested the hypothesis that the reintroduction of the FMR1 gene is able to revert the AGS susceptibility characterizing Fmr1 KO mice. To this aim, two groups of Fmr1 KO transgenic mice, which have additional copies of the human FMR1 gene (YAC) or FMR1 cDNA (G6) were used. AGS susceptibility of these mice was examined and compared to that of Fmr1 KO, wild type, and wild-type animals in whom the FMR1gene was also introduced (over-expressed). Mice were tested at different ages because AGS susceptibility is age dependent. The intensity of response was scored and the results were analyzed by means of 2-way analysis of variance to evaluate the effects of age and genetic condition. We found that AGS susceptibility rescue is complete in the G6 mice and partial in YAC mice. Our data indicate that the introduction of the human FMR1 gene in Fmr1 KO mice is able to revert the Fmr1 KO epileptic phenotype.

Acoustic Stimulation↗

Long-term remission in BCR/ABL-positive AML-M6 patient treated with Imatinib Mesylate.

BCR/ABL-positive acute myeloid leukemia (AML) is a rare disease, characterized by a poor prognosis, with resistance to induction chemotherapy and frequent relapses in responsive patients. Here we report a case of BCR/ABL-positive AML-M6 who, after relapse, was treated with Imatinib Mesylate (600 mg/die) and within 4 months achieved a cytogenetic and molecular complete response. After more than 4 years of continuous Imatinib therapy, nested RT-PCR for BCR/ABL is persistently negative. The case reported shows that the response obtained with Imatinib Mesylate in BCR/ABL-positive AML may be long lasting, offering a chance of successful treatment for this poor prognosis group of patients.

Antineoplastic Agents↗

Genomic and expression profiling identifies the B-cell associated tyrosine kinase Syk as a possible therapeutic target in mantle cell lymphoma.

Among B-cell lymphomas mantle cell lymphoma (MCL) has the worst prognosis. By using a combination of genomic and expression profiling (Affymetrix GeneChip Mapping 10k Xba131 and U133 set), we analysed 26 MCL samples to identify genes relevant to MCL pathogenesis and that could represent new therapeutic targets. Recurrent genomic deletions and gains were detected. Genes were identified as overexpressed in regions of DNA gain on 3q, 6p, 8q, 9q, 16p and 18q, including the cancer genes BCL2 and MYC. Among the transcripts with high correlation between DNA and RNA, we identified SYK, a tyrosine kinase involved in B-cell receptor signalling. SYK was amplified at DNA level, as validated by fluorescence in situ hybridisation (FISH) analysis, and overexpressed at both RNA and protein levels in the JeKo-1 cell line. Low-level amplification, with protein overexpression of Syk was demonstrated by FISH in a small subset of clinical samples. After treatment with low doses of the Syk inhibitor piceatannol, cell proliferation arrest and apoptosis were induced in the cell line overexpressing Syk, while cells expressing low levels of Syk were much less sensitive. A combination of genomic and expression profiling suggested Syk inhibition as a new therapeutic strategy to be explored in lymphomas.

Apoptosis↗

Fluorescence in situ hybridization analysis of minimal residual disease and the relevance of the der(9) deletion in imatinib-treated patients with chronic myeloid leukemia.

Forty-six patients with chronic myeloid leukemia receiving imatinib mesylate (39 in chronic phase, one in accelerated phase, and six in blastic crisis), were studied for a 20-62 month follow-up period by cytogenetics and fluorescence in situ hybridization using dual-color, dual-fusion BCR and ABL probes. This approach provided valuable results for disease management of analysis.

Benzamides↗

Identification of deletions and duplications of the DMD gene in affected males and carrier females by multiple ligation probe amplification (MLPA).

Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD) are caused in the majority of cases by deletions of the DMD gene and are readily detectable in affected males by multiplex polymerase chain reaction (PCR). However, different approaches must be used for the identification of female carriers, in which deletions are not detectable by PCR, because of the presence of a normal X chromosome. In this study, we used the multiple ligation probe amplification (MLPA) tool for the identification of female carriers of DMD deletions or duplications in 12 families with a single affected male, 10 of which were previously diagnosed as carriers of a DMD rearrangement, and the remaining two as having an unknown disease-causing mutation. In all the investigated affected males, MLPA analysis confirmed the presence of a DMD rearrangement, and in six of them allowed the refinement of the breakpoints. In 12 female relatives of the affected patients, MLPA analysis showed a DMD deletion or duplication, confirming their carrier status. Two of these were the mother and the sister of a patient whose disease-causing mutation was not known. MLPA analysis thus proved to be an useful tool for the analysis of both affected males and females carriers of DMD rearrangements in cases in which the disease-causing mutation in the affected male was not known, providing useful information for the genetic counselling of the family.

Chromosomes, Human, X↗

Lack of correlation between elevated maternal serum hCG during second-trimester biochemical screening and fetal congenital anomaly.

OBJECTIVE: Isolated elevations in midtrimester maternal serum human chorionic gonadotrophin concentrations (MShCG) have been reported to be associated with a substantially increased likelihood of fetal congenital malformations. The reported malformations included a wide range of organ systems, originating at different embryologic developmental stages. The purpose of our study was to determine the significance of an isolated elevated MShCG (>2.5 MoM) in midtrimester for the detection of fetal structural anomalies in a large population. METHODS: Among 10,144 women who underwent a biochemical triple screen at 15 to 18 weeks' gestation, 463 patients, who had an elevated MShCG, but normal alpha-fetoprotein (AFP) and unconjugated estriol (uE3) levels, were identified. Patients with an integrated calculated Down syndrome risk above 1:250 were excluded. Only nonsmokers, at ages <35 years, without a history of prior fetal anomalies were included. The control group consisted of 463 patients with normal serum analyte concentrations and Down syndrome risks below 1:250, who were matched for maternal age and date of biochemical screen. All patients underwent a detailed genetic sonogram in which an anatomic survey and multiple 'soft markers' for aneuploidy were looked for. Newborns were examined by a senior pediatrician trained in dysmorphology. RESULTS: MShCG levels were 3.18 +/- 0.72 versus 0.99 +/- 0.43 MoM (p < 0.0001) in study and control groups respectively. Sonography revealed 8 versus 6 cases of major congenital anomalies among the 463 patients of their respective groups, and 39 versus 36 sonographic 'soft markers' for aneuploidy. Fetal karyotyping and neonatal examination for dysmorphology revealed 6 chromosomal anomalies (4 Down syndrome; 2 Turner syndrome) among the 8 major malformations in the study group, but none in the controls (p < 0.0001). Three of the 39 fetuses with 'soft markers' and elevated MShCG were found to have trisomy 21. CONCLUSION: Isolated elevation of MShCG does not confer an increased risk of fetal congenital anomalies other than chromosomal abnormalities. However, elevated MShCG levels in combination with sonographic 'soft markers' for aneuploidy were associated with a high incidence of chromosomal anomalies, despite a normal biochemical triple screen risk estimate.

Adult↗

Identification in chromosome 8q11 of a region of homology with the g1 amplicon of the Y chromosome and functional analysis of the BEYLA gene.

The male-specific region (MSY) of the Y chromosome contains genes involved mainly in male sex determination and in spermatogenesis. The majority of genes involved in male fertility are localized in multiple copies in the long arm of the Y chromosome, within specific regions defined as "ampliconic regions." It has been suggested that these genes derived from X-linked or autosomal ancestors during evolution, providing a benefit for male fertility when transposed onto the Y chromosome. So far, the autosomal origin has been demonstrated only for two MSY genes, DAZ and CDY. In the present study we report on the identification within chromosome 8q11.2 of a region homologous to the g amplicon, containing the VCY2 (approved gene symbol BPY2), TTTY4, and TTTY17 genes. A search for ancestor genes within the 8q11.2 region allowed us to identify a gene named BEYLA and to characterize the genomic organization and the expression patterns of this gene.

Animals↗

Screening of mutations in the CFTR gene in 1195 couples entering assisted reproduction technique programs.

Genetic testing of the cystic fibrosis transmembrane conductance (CFTR) gene is currently performed in couples undergoing assisted reproduction techniques (ART), because of the high prevalence of healthy carriers in the population and the pathogenic relationship with congenital bilateral absence of vas deferens (CBAVD). However, discordant data have been reported concerning the usefulness of this genetic test in couples with no family history of cystic fibrosis (CF). In this study, we report the results of CFTR molecular screening in 1195 couples entering ART. Genetic testing was initially carried out in a single partner of each couple. CFTR mutations were detected in 55 subjects (4.6%), a percentage that overlaps with the one reported in the general population. However, significantly higher frequencies of were found in CBAVD individuals (37.5%) and in males with nonobstructive azoospermia (6.6%). The 5T allele was found in 78 patients (6.5%). This figure was again significantly different in males with nonobstructive-azoospermia (9.9%) and in those with CBAVD (100%). All together, 139 subjects (11.6%) had either a CFTR mutation or the 5T allele. Subsequent molecular analysis of their partners disclosed a CFTR mutation or 5T allele in nine cases (6.5%). However, none of these couples had CFTR alterations in both members, a CFTR mutation being invariably present in one partner and the 5T allele in the other. In order to improve genetic counselling of these couples, the TG-M470V-5T association was analyzed, and a statistically significant relationship between 12TG-V470 and CBAVD was detected.

Alleles↗

Identification of 14 rare marker chromosomes and derivatives by spectral karyotyping in prenatal and postnatal diagnosis.

Extra structurally abnormal chromosomes (ESACs) and cryptic rearrangements are often associated with mental retardation and phenotypic abnormalities. In some cases their characterisation, using standard cytogenetic techniques and fluorescence in situ hybridization (FISH), is difficult and time consuming, where a fast and accurate identification is essential, especially when such chromosomal aberrations are found in prenatal diagnosis. A recent molecular technique, spectral karyotyping (SKY), based on the spectral signature of 24 chromosome-specific painting probes labelled with different combinations of five fluorochromes, allows the simultaneous visualisation of all human chromosomes in different colours. We used SKY analysis on 14 cases with rare ESACs or cryptic unbalanced rearrangements found at pre- or postnatal diagnosis. SKY analysis permitted the classification of chromosome rearrangements in all 14 cases analysed in combination with FISH analysis.

Chromosome Aberrations↗

Grafts of microencapsulated pancreatic islet cells for the therapy of diabetes mellitus in non-immunosuppressed animals.

Pancreatic-islet-cell transplantation may reverse hyperglycaemia in diabetic recipients that undertake general pharmacological immunosuppression. A major challenge that remains is the need to avoid immunosuppression associated with the use of allogeneic or heterologous islet cells. In the present study we demonstrate the use of microencapsulation of cells using artificial biocompatible and permselective membranes prepared with alginic acid derivatives and polyamino acids. While characterization of the microcapsule constituent polymers continues to progress, other technical issues such as definition of the immunobarrier capacity, biocompatibility, size, shape and graft site have come into sharper focus. Assessment of microcapsules properties, in order to establish possible guidelines for fabrication of reproducible membranes, and results from both in vitro functional testing, and in vivo encapsulated-islet-transplant outcome in several animal models of diabetes are reported.

Alginates↗

Chromosome 11 rearrangements and specific MLL amplification revealed by spectral karyotyping in a patient with refractory anaemia with excess of blasts (RAEB).

A patient with refractory anaemia with excess of blasts (RAEB) had a complex karyotype with multiple markers. Spectral karyotyping (SKY) showed rearrangements including three different der(11), containing a very high number of MLL gene copies, shown by fluorescence in situ hybridization (FISH) analysis. Fibre-FISH experiments disclosed the presence of chromatin fibres with multiple MLL copies with a head-to-tail pattern. Apparently, no other region flanking the MLL site was present in the three der(11). MLL amplification was confirmed by the reverse transcription polymerase chain reaction (RT-PCR). The patient died 6 months after diagnosis, supporting the severe prognosis of sole MLL amplification.

Aged↗

C677T mutation in the 5,10-MTHFR gene and risk of Down syndrome in Italy.

The C677T polymorphism of the MTHFR gene has been associated to maternal risk of Down syndrome, due to the detection of an higher prevalence of the T allele among mothers of children with trisomy 21, compared to control mothers. In order to confirm this association, we studied the presence of the C677T in 64 mothers of Down syndrome children and 112 controls from central Italy. An higher incidence of the mutant T allele in controls (48.2%) than in Down syndrome children mothers (44%) was detected. These results do not support the presence of an increased risk of Down syndrome in mothers carriers of the T allele in the Italian population.

Down Syndrome↗

Continuous subcutaneous glucose monitoring in diabetic patients: a multicenter analysis.

OBJECTIVE: To evaluate the accuracy of a new subcutaneous glucose sensor (Glucoday; A. Menarini Diagnostics) compared with venous blood glucose measurement in type 1 and type 2 diabetic patients. RESEARCH DESIGN: A multicenter study was performed in 70 diabetic patients. A microdialysis fiber was inserted subcutaneously into the periumbelical region and perfused with a buffer solution. Glucose concentrations in the dialysate were then measured every 3 min by the glucose sensor over a 24-h period, during which nine venous blood samples were also collected throughout the day. RESULTS: Both the insertion of the fiber and the wearing of the device were well tolerated by the patients. Subcutaneous glucose levels were well correlated with venous glucose measurements (r = 0.9, P < 0.001) over a wide range (40-400 mg/dl) for up to 24 h, with a single-point calibration. An analysis of 381 data pairs showed a linear relationship between the GlucoDay and serial venous blood glucose levels, and 97% of the data fell in the A and B regions of the error grid analysis. Percentage bias between the GlucoDay and the blood venous levels was -2.0% in the hypoglycemic range (<70 mg/dl), 6.9% in the euglycemic range (70-180 mg/dl), and 11.2% in the hyperglycemic range (>180 mg/dl). CONCLUSIONS: The GlucoDay system demonstrated high reliability and reported values that closely agreed with venous blood glucose measurements. The system was well tolerated and thus constitutes a relatively easy method to monitor glucose excursions in diabetic patients.

Adult↗

A peptidase gene in chromosome 8q is disrupted by a balanced translocation in a duane syndrome patient.

PURPOSE: To identify the gene disrupted by a de novo reciprocal balanced translocation t(6;8)(q26;q13) in a patient with Duane retraction syndrome (DURS). The break point in chromosome arm 8q is positioned within the DURS1 critical region. METHODS: Fluorescence in situ hybridization (FISH) analysis using cosmid and BAC clones covering the DURS1 locus was performed to define the break point position and its relationship with expressed sequence tags (ESTs) in the region. Once the interrupted gene was identified, the full-length cDNA was sequenced and the genomic organization defined. Eighteen patients with sporadic DURS without cytogenetic abnormalities involving the DURS1 region were screened for point mutations in the candidate DURS1 gene. RESULTS: A carboxypeptidase gene (CPAH) was directly interrupted between the first and second exons in a patient with DURS who carried a de novo reciprocal balanced translocation t(6;8)(q26;q13) involving the DURS1 region on chromosome arm 8q13. The gene was transcribed in at least two alternative mRNA forms, with different start and stop codons. CONCLUSIONS: The CPAH gene was interrupted in a patient with DURS carrying a translocation break point in the DURS1 region on chromosome 8q13. CPAH is therefore a likely candidate for this abnormality, even if the possibility that other genes are involved, either by direct effects on transcription units present in the first CPAH intron or by position effects, cannot be ruled out. Functional studies of the influence of this gene on the morphogenesis of eye muscles and their innervation may clarify this question.

Adult↗