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P Lapunzina

Publications and source records attributed to P Lapunzina.

At least 19 recordsLinked to original sources
PubMed2006

Euchromatic variant 16p+. Implications in prenatal diagnosis.

BACKGROUND: Euchromatic imbalances at the cytogenetic level are usually associated with phenotypic consequences. Among the exceptions are euchromatic variants of chromosome 16 (16p+) with normal phenotype. There is a growing list of euchromatic duplications and deletions involving both G-positive and G-negative bands that seem to be phenotypically neutral, but these euchromatic variants are rare. OBJECTIVE: The aim of this report is to describe a new familial case of euchromatic variant 16p+ and to emphasise the misinterpretation of these rare euchromatic variants particularly when ascertained at prenatal diagnosis. METHODS AND RESULTS: Fluorescence in situ hybridisation with clone RP11-261A7 showed an amplified signal in the larger chromosome 16. This clone contains FLJ43855 gene, similar to sodium- and chloride-dependent creatine transporter. CONCLUSION: So, this 16p+ variant that involves amplification of pseudogenetic sequences is considered a polymorphism in normal individuals.

Adult↗
PubMed2006

MLPA vs multiprobe FISH: comparison of two methods for the screening of subtelomeric rearrangements in 50 patients with idiopathic mental retardation.

Subtelomeric rearrangements not visible by conventional cytogenetic analysis have been reported to occur in approximately 5% of patients with unexplained mental retardation (MR). As the prevalence of MR is high, many patients need to be screened for these chromosomal abnormalities routinely. Multiplex ligation-dependent probe amplification (MLPA) is a new technique for measuring sequence dosage, allowing large number of samples to be processed simultaneously and thus significantly reducing laboratory work. We have assessed its performance for the detection of subtelomeric rearrangements by comparing the results with those of our previous multiprobe fluorescence in situ hybridization (FISH) assay. We have tested 50 patients with idiopathic MR, dysmorphic features, congenital malformations, and/or familial history of MR. Our results show a high degree of concordance between the two techniques for the 50 samples tested. On the basis of these results, we conclude that MLPA is a rapid, accurate, reliable, and cost-effective alternative to FISH for the screening of subtelomeric rearrangements in patients with idiopathic MR.

Chromosome Aberrations↗
PubMed2005

Deletions involving long-range conserved nongenic sequences upstream and downstream of FOXL2 as a novel disease-causing mechanism in blepharophimosis syndrome.

The expression of a gene requires not only a normal coding sequence but also intact regulatory regions, which can be located at large distances from the target genes, as demonstrated for an increasing number of developmental genes. In previous mutation studies of the role of FOXL2 in blepharophimosis syndrome (BPES), we identified intragenic mutations in 70% of our patients. Three translocation breakpoints upstream of FOXL2 in patients with BPES suggested a position effect. Here, we identified novel microdeletions outside of FOXL2 in cases of sporadic and familial BPES. Specifically, four rearrangements, with an overlap of 126 kb, are located 230 kb upstream of FOXL2, telomeric to the reported translocation breakpoints. Moreover, the shortest region of deletion overlap (SRO) contains several conserved nongenic sequences (CNGs) harboring putative transcription-factor binding sites and representing potential long-range cis-regulatory elements. Interestingly, the human region orthologous to the 12-kb sequence deleted in the polled intersex syndrome in goat, which is an animal model for BPES, is contained in this SRO, providing evidence of human-goat conservation of FOXL2 expression and of the mutational mechanism. Surprisingly, in a fifth family with BPES, one rearrangement was found downstream of FOXL2. In addition, we report nine novel rearrangements encompassing FOXL2 that range from partial gene deletions to submicroscopic deletions. Overall, genomic rearrangements encompassing or outside of FOXL2 account for 16% of all molecular defects found in our families with BPES. In summary, this is the first report of extragenic deletions in BPES, providing further evidence of potential long-range cis-regulatory elements regulating FOXL2 expression. It contributes to the enlarging group of developmental diseases caused by defective distant regulation of gene expression. Finally, we demonstrate that CNGs are candidate regions for genomic rearrangements in developmental genes.

Animals↗
PubMed2005

Oculocerebrocutaneous (Delleman) syndrome: report of two cases.

We describe two cases of oculocerebrocutaneous syndrome (OCCS) or Delleman syndrome, characterized by congenital anomalies that involve the skin, orbit, and central nervous system (CNS). Complete MRI studies of the orbit, CNS and the entire spinal region must be performed in these cases. New MRI techniques can show cortical malformations, such as polymicrogyria, lissencephaly, or abnormal disposition of cortical sulci and gyri. Lesions can be bilateral or unilateral, as occurred in our patients. In one case, the ocular, skin, cerebral, and cerebellar lesions involved mainly the same side, whereas in the second case, all anomalies were generalized and the patient also showed skin hypopigmented lesions distributed bilaterally. Both patients show severe encephalopathy and Dandy-Walker malformation. One case is blind and shows generalized hydrocephalus, and the other one has vision through an eye, and has complete agenesis of the corpus callosum and severe disorder of neuronal migration and cortical organization with polymicrogyria and abnormal cortical sulci and gyri in a cerebral hemisphere. Our second case shows arachnoid cysts in both temporal, retrocerebellar, and spinal (D(8)-D(11)) regions, and lipoma in the pontomedullary and spinal (D(4)-D(7)) regions. The latter features correspond more to ECCL than to OCCS. The overlap between the two syndromes is unquestionable and it is possible that they constitute different manifestations of the same disorder.

Abnormalities, Multiple↗
PubMed2005

Comparative study of three diagnostic approaches (FISH, STRs and MLPA) in 30 patients with 22q11.2 deletion syndrome.

The 22q11.2 deletion syndrome is commonly diagnosed using fluorescence in situ hybridization (FISH) with commercial probes. The chromosomal breakpoints and deletion size are subsequently characterized by short tandem repeat (STR) segregation tests or by further FISH probes. Recently, a multiplex ligation-dependent probe amplification (MLPA) single tube assay was developed to detect deletions of the 22q11.2 region and other chromosomal regions associated with DiGeorge/velocardiofacial syndrome. We have compared the results of these three techniques in a group of 30 patients affected with 22q11.2 deletion syndrome. MLPA correctly called all patients who had been previously diagnosed by FISH. The MLPA results were concordant in all patients with the STR analysis in respect to deletion size. Furthermore, this novel technique resolved seven cases that were undetermined by STR analysis. These results confirm the efficiency of MLPA as a rapid, reliable, economical, high-throughput method for the diagnosis of 22q11.2 deletion syndrome.

Chromosome Deletion↗
PubMed2003

Tetrasomy 8p: discordance of amniotic fluid and blood karyotypes.

We describe a girl with congenital heart defect (ventricular septal defect), facial, ear and bone anomalies, agenesis of corpus callosum and conventional cytogenetic studies showing tetrasomy 8p. The identity of the isochromosome was confirmed by fluorescent in situ hybridization (FISH) using painting, subtelomeric and alpha satellite probes for chromosome 8. The extra isochromosome was observed in 100% of cultured peripheral lymphocytes (47,XX,+i(8)(p10)), but normal chromosomes were recorded in cultured amniotic fluid. Microsatellites analysis of the patient's DNA with two markers mapping 8p showed three different peaks, and two markers mapping 8q showed two peaks. To the best of our knowledge, this patient represents the twelfth reported case of tetrasomy 8p. In addition, our report is the first case with a pure tetrasomy 8p in blood, (the other published cases are mosaic 8p), and the second case with a discordance of amniotic fluid and blood karyotypes [Robinow et al., 1989: Am J Med Genet 32:320-324].

Abnormalities, Multiple↗
PubMed2002

Autosomal recessive hydrocephalus due to aqueduct stenosis: report of a further family and implications for genetic counselling.

We report on two abortuses with hydrocephalus due to congenital stenosis of the aqueduct of Silvius. The occurrence of this disorder in two siblings (a male and a female) with normal parents supports the autosomal recessive pattern of inheritance. Such a mechanism of inheritance should be taken into account when counselling families with congenital hydrocephaly due to aqueduct stenosis.

Adult↗
PubMed2002

[Crouzon's syndrome with acanthosis nigricans].

Crouzon's syndrome is a complex craniosynostosis disorder due to mutations in fibroblast growth factor receptor (FGFR) type 2. We report a female patient with Crouzon's syndrome associated with acanthosis nigricans. The molecular abnormality in this patient is a point mutation (Ala391Glu) in the transmembrane domain of another FGFR (type 3), which is very close to the mutation (Gly380Arg) most frequently observed in achondroplasia. Acanthosis nigricans is an emerging disorder. Its clinical features and molecular findings differ from those of isolated Crouzon's syndrome. These data are very useful when molecular tests are required for prenatal diagnosis.

Acanthosis Nigricans↗
PubMed2001

Semilobar holoprosencephaly, coronal craniosynostosis, and multiple congenital anomalies: a severe expression of the Genoa syndrome or a newly recognized syndrome?

We report on a female newborn with holoprosencephaly, craniosynostosis, and multiple congenital anomalies including cloverleaf skull, Dandy-Walker malformation, bilateral microphthalmia, cleft soft palate, congenital scoliosis, hypoplastic nails and coarctation of aorta. Some of these features are consistent with the diagnosis of the Genoa syndrome, (MIM 601370) a rare autosomal recessive disorder recently described. The findings of other serious and previously undescribed malformations, however, raises the possibility of a newly recognized disorder.

Abnormalities, Multiple↗
PubMed2000

Mitral and tricuspid valve rupture after moderate blunt chest trauma.

We present a patient with rupture of both atrioventricular valves in a previously healthy adult man who sustained a 5-foot fall. The mechanism of injury was such that it would not necessarily raise an adequate index of suspicion for valvular damage had valvular rupture not occurred. The usefulness of perioperative echocardiography is highlighted.

Accidental Falls↗
PubMed1998

Research in two large pediatric residencies in Argentina.

PURPOSE: To obtain data about residents' research, knowledge of informatics, and proficiency in English in two pediatric residencies in Argentina. METHOD: Data collected in 1996 using a ten-item questionnaire were evaluated using EpiInfo software. Regression coefficients, odd ratios, and confidence intervals were calculated using logistic multivariate regression analysis (Hosmer-Lemeshow test). RESULTS: Of 249 residents surveyed, 227 (91.1%) answered the questionnaire. Of those, 224 (98.7%) thought that research during residency was useful; 63% believed that research should be required to obtain residency certification. One third of the respondents had presented at least one work or poster, or had published at least one research article. Among the two thirds who had not done so, the majority explained that they had been hindered by lack of mentors, time, or institutional support. Seventy-five percent of the respondents were reasonably proficient in English. A statistically significant association was found between knowledge of how to use statistical software and publication of papers (OR 4.5; 95% CI, 1.37-15.62; p < .003). CONCLUSION: The vast majority of respondents thought that research was useful and should be included in pediatric residency programs. Most thought that it should be required to obtain residency certification. If it is to be required, it should include trained, full-time mentors, time exclusively devoted to research, and courses in research methodology, informatics, and statistics.

Argentina↗
PubMed1998

A patient with Simpson-Golabi-Behmel syndrome and hepatocellular carcinoma.

Simpson-Golabi-Behmel syndrome (SGBS) is an X linked disorder characterised by pre- and postnatal overgrowth, coarse facial features, and visceral and skeletal abnormalities. Like other overgrowth syndromes, in the SGBS there is an increased risk for developing neoplasia, mainly embryonic, such as Wilms tumour. We report a 3 year old male patient with SGBS and hepatocellular carcinoma, a previously undescribed tumour associated with the syndrome.

Carcinoma, Hepatocellular↗
PubMed1995

Mulibrey nanism: three additional patients and a review of 39 patients.

We report on 3 patients with Mulibrey nanism (MN), or Perheentupa syndrome: the first 2 sibs from Argentina and a new patient from Spain. All 3 patients had growth failure, short stature, abnormal pigmentary retinal changes, and a J-shaped sella turcica. These findings are considered major criteria of MN. Two had pericardial constriction, which is a frequent and life-threatening abnormality in this syndrome. MN is a rare autosomal recessive condition. Reviewing the 39 patients described so far, we have classified the anomalies into the very frequent (present in more than 66%), frequent (in at least 25%), and not frequent. Identifying the anomalies specific to MN should help its early diagnosis and treatment.

Abnormalities, Multiple↗
PubMed1995

Rothmund-Thomson syndrome and Addison disease.

We report an 18-year-old man with the unusual combination of Rothmund-Thomson syndrome (RTS) and Addison disease. He was admitted when he was 26 months old because of short stature, dehydration, metabolic acidosis, hyperpigmentation, and typical skin lesions. Because his growth remained delayed, at age 10 years he was given a trial of recombinant growth hormone. After six years of treatment no improvement in height, bone, or sexual maturation was observed. This fact may be related to a defect in connective tissue metabolism. Chromosomal analysis of peripheral blood lymphocytes revealed increased numbers of breaks and gaps. Fibroblasts cultured from affected skin did not grow. Patients with RTS are prone to developing cancer, but no malignant disease was found in our patient. Early diagnosis and treatment of both endocrinologic and malignant complications are essential for survival of patients with this rare syndrome.

Acidosis↗