Biomedical subjects

Claudia Perandones

Publications and source records attributed to Claudia Perandones.

6 recordsLinked to original sources

PubMed2006

Anp32e/Cpd1 regulates protein phosphatase 2A activity at synapses during synaptogenesis.

Anp32e/Cpd1, a member of the acidic nuclear phosphoprotein (Anp)32 family, is characterized by the presence of an amino terminal domain containing four leucine-rich repeats and a carboxyl-terminal low-compositional complexity acidic region. In previous studies performed to understand the biological role of Anp32e/Cpd1, we showed a predominant presence of Anp32e/Cpd1 in the nucleus. However, when Anp32e/Cpd1 is in the cytoplasm, it co-localizes spatially with protein phosphatase 2A (PP2A) near cell membranes, far from the synapses. In the present work, we show that Anp32e/Cpd1 is also present as a membrane-bound 74/76-kDa protein with a widespread distribution in the brain. We reveal that the expression, synthesis and half-life of this high-molecular-weight form of Anp32e/Cpd1 are spatially and temporally correlated with the cerebellar synaptogenesis period. We demonstrate that synaptic Anp32e/Cpd1 co-localizes, interacts and inhibits PP2A activity, and that phosphorylation of Anp32/Cpd1 is required for the Anp32e-PP2A interaction. Also, subcellular localization was shown with electronic microscopy. Finally, we examine Anp32e/Cpd1 and PP2A distribution in two ataxic mutant models, weaver and staggerer, and show that their co-localization in Purkinje cell dendrites depends on parallel fibre/Purkinje cell contacts. Based on these observations, we propose that Anp32e/Cpd1 mediates synaptogenesis process by modulating PP2A activity.

Age Factors↗

PubMed2005

Uses and limitations of two molecular cytogenetic techniques for the study of arrested embryos obtained through assisted reproduction technology.

We studied chromosomal abnormalities in arrested embryos produced by assisted reproductive technology with fluorescence in situ hybridization (FISH) and comparative genomic hybridization (CGH) in order to determine the best technique for evaluating chromosomal aneusomies to be implemented in different situations. We examined individual blastomeres from arrested embryos by FISH and arrested whole embryos by CGH. All of the 10 FISH-analyzed embryos gave results, while only 7 of the 30 embryos analyzed by CGH were usable. Fifteen of the 17 embryos were chromosomally abnormal. CGH provided more accurate data for arrested embryos; however, FISH is the technique of choice for screening in preimplantation genetic diagnosis, because the results can be obtained within a day, while the embryos are still in culture.

Chromosome Disorders↗

PubMed2005

Family environment of individuals with oral clefts in Argentina.

OBJECTIVE: The purpose of this investigation was to study the social environment of families of children with different types of nonsyndromic oral clefts (OC) and to compare these groups with a control population of families of children without clefts. DESIGN: The study compared three nonsyndromic oral cleft groups and the control group using the Moos Family Environment Scale, which examines cohesion, expressiveness, conflict, independence, achievement-orientation, intellectual-cultural orientation, active-recreational orientation, moral-religious emphasis, organization, and control. SETTING: All parents of children with nonsyndromic oral clefts from a large craniofacial clinic in Buenos Aires, Argentina, were identified and were enrolled in this study between June 2000 and August 2001. Control families were ascertained from the pediatrics service of a hospital located in the vicinity of the craniofacial clinic. PARTICIPANTS: One hundred and sixty-five parents were selected, based on having a child with nonsyndromic unilateral cleft lip with or without cleft palate (UCL/P), bilateral cleft lip with or without cleft palate (BCL/P), or isolated cleft palate (ICP). One hundred and eighty control parents with no family history of congenital anomalies were selected, as well. RESULTS: There was no major difference in the social environment of families of children with different types of nonsyndromic oral clefts. When compared with families in the control group, families of children with nonsyndromic oral clefts scored better in all three subdimensions of family relationship, revealed a high level of independence, and showed better structure and organization than control families did; however, families of children with nonsyndromic oral clefts reported participating in fewer recreational activities. CONCLUSIONS: Overall, families of children with nonsyndromic oral clefts displayed a good social environment. Efforts should be focused to involve them in recreational activities.

Adaptation, Psychological↗

PubMed2004

Correlation between synaptogenesis and the PTEN phosphatase expression in dendrites during postnatal brain development.

The PTEN (phosphatase and tensin homolog deleted on chromosome 10) tumor suppressor gene codifies a lipid inositol 3'-phosphatase that negatively regulates cell survival mediated by the phosphatidyl inositol 3' kinase (PIP3-kinase)--protein kinase B/Akt signaling pathway. Recently, PIP3-kinase was involved in axon polarization, but PTEN functions in dendrites are uncertain. Using amino-terminal antibodies against the catalytic domain, we found a 34 kDa fragment of PTEN protein detected only in mouse brain tissue, present in neuron dendrites and spines of cerebral cortex, cerebellum, hippocampus and olfactory bulb. The PTEN-fragment reaches the synaptic fraction with a positive temporal correlation with synaptic stabilization in postnatal cerebellum and brain. In the weaver mutant mice, PTEN was absent only in the Purkinje cells dendrites that cannot receive the granule cells synaptic input. Furthermore, the activated p-Akt/PKB was present in axons but not in dendrites of mature neuron cells. P-Akt was also altered by the weaver mutation maintaining the inverse correlation with the PTEN-fragment in Purkinje cell dendrites. In contrast, the expression of this fragment was not affected by the staggerer mutation. Together, these results suggest that synaptogenesis is a necessary process for polarization in PIP3 pathway mediated by the PTEN catalytic-fragment into dendrites of CNS neurons.

Animals↗

PubMed2003

Attitudes toward prenatal diagnosis, termination of pregnancy, and reproduction by parents of children with nonsyndromic oral clefts in Argentina.

OBJECTIVE: To investigate the attitudes of Argentine parents of children with nonsyndromic oral clefts with respect to prenatal diagnosis, termination of pregnancy, and reproduction and to assess the variables that might influence their responses. DESIGN: One hundred and sixty-five parents of children with oral clefts, ascertained from a craniofacial clinic in the suburbs of Buenos Aires, answered a 151-item semistructured questionnaire. The questionnaire included sections covering sociodemographic information, level of religiousness, characteristics of the child's cleft, parental perception of their child's cleft, pregnancy history, recurrence risk, access to health care, attitudes in regard to abortion, and family environment. RESULTS: Most parents (60%) believe their child's cleft is not a serious condition. None of the respondents would terminate a pregnancy because the ultrasound reveals an oral cleft. Similarly, very few (6.1%) would terminate the pregnancy if there were an early diagnosis of Down syndrome. Half of the respondents believe that abortion should not be an option for any couple expecting a child. CONCLUSIONS: Most respondents do not perceive oral clefts as a severe condition. Parents would not choose to terminate the pregnancy over delivery of such an affected newborn.

Abortion, Induced↗

PubMed2003

Evidence for linkage of nonsyndromic cleft lip with or without cleft palate to a region on chromosome 2.

Results from a genome-wide screen of 10 multiplex families ascertained through probands with nonsyndromic cleft lip with or without cleft palate (CL/P) in Mexico, Argentina, and the United States yielded suggestive evidence of linkage to chromosomes 2, 6, 17 and 18. Fine mapping excluded all regions except chromosome 2. Subsequent analysis was performed on the original 10 families plus an additional 16 families using 31 markers on chromosome 2. This analysis showed intriguing evidence of linkage to 2q (Zlr=2.26, empirical P-value=0.028 in a chromosome-wide analysis). Transmission disequilibrium tests also revealed evidence of linkage and disequilibrium for two markers in this region (D2S168 and D2S1400 with P-values=0.022 and 0.006, respectively). A subset of these 26 families provided additional evidence for a susceptibility gene for CL/P on 2q, suggesting that further studies of genes in this region are warranted.

Chromosome Mapping↗