Search PubMed⌕ Search

Biomedical subjects

M Angelo

Publications and source records attributed to M Angelo.

At least 19 recordsLinked to original sources
PubMed2005

Sexual dimorphisms in the effect of low-level p25 expression on synaptic plasticity and memory.

p25, a degradation product of p35, has been reported to accumulate in the forebrain of patients with Alzheimer's disease. p25 as well as p35 are activators of cyclin-dependent kinase 5 (Cdk5) although p25/Cdk5 and p35/Cdk5 complexes have distinct properties. Several mouse models with high levels of p25 expression exhibit signs of neurodegeneration. On the contrary, we have shown that low levels of p25 expression do not cause neurodegeneration and are even beneficial for particular types of learning and memory [Angelo et al., (2003) Eur J. Neurosci., 18, 423-431]. Here, we have studied the influence of low-level p25 expression in hippocampal synaptic plasticity and in learning and memory for each sex separately in two different genetic backgrounds (129B6F1 and C57BL/6). Surprisingly, we found that low-level p25 expression had different consequences in male and female mutants. In the two genetic backgrounds LTP induced by a strong stimulation of the Schaffer's collaterals (four trains, 1-s duration, 5-min interval) was severely impaired in male, but not in female, p25 mutants. Furthermore, in the two genetic backgrounds spatial learning in the Morris water maze was faster in female p25 mutants than in male transgenic mice. These results suggest that, in women, the production of p25 in Alzheimer's disease could be a compensation for some early learning and memory deficits.

Animals↗
PubMed2004

GeneCluster 2.0: an advanced toolset for bioarray analysis.

SUMMARY: GeneCluster 2.0 is a software package for analyzing gene expression and other bioarray data, giving users a variety of methods to build and evaluate class predictors, visualize marker lists, cluster data and validate results. GeneCluster 2.0 greatly expands the data analysis capabilities of GeneCluster 1.0 by adding classification, class discovery and permutation test methods. It includes algorithms for building and testing supervised models using weighted voting and k-nearest neighbor algorithms, a module for systematically finding and evaluating clustering via self-organizing maps, and modules for marker gene selection and heat map visualization that allow users to view and sort samples and genes by many criteria. GeneCluster 2.0 is a stand-alone Java application and runs on any platform that supports the Java Runtime Environment version 1.3.1 or greater. AVAILABILITY: http://www.broad.mit.edu/cancer/software

Algorithms↗
PubMed2001

Multiclass cancer diagnosis using tumor gene expression signatures.

The optimal treatment of patients with cancer depends on establishing accurate diagnoses by using a complex combination of clinical and histopathological data. In some instances, this task is difficult or impossible because of atypical clinical presentation or histopathology. To determine whether the diagnosis of multiple common adult malignancies could be achieved purely by molecular classification, we subjected 218 tumor samples, spanning 14 common tumor types, and 90 normal tissue samples to oligonucleotide microarray gene expression analysis. The expression levels of 16,063 genes and expressed sequence tags were used to evaluate the accuracy of a multiclass classifier based on a support vector machine algorithm. Overall classification accuracy was 78%, far exceeding the accuracy of random classification (9%). Poorly differentiated cancers resulted in low-confidence predictions and could not be accurately classified according to their tissue of origin, indicating that they are molecularly distinct entities with dramatically different gene expression patterns compared with their well differentiated counterparts. Taken together, these results demonstrate the feasibility of accurate, multiclass molecular cancer classification and suggest a strategy for future clinical implementation of molecular cancer diagnostics.

Biomarkers, Tumor↗
PubMed2001

Molecular classification of multiple tumor types.

Using gene expression data to classify tumor types is a very promising tool in cancer diagnosis. Previous works show several pairs of tumor types can be successfully distinguished by their gene expression patterns (Golub et al. 1999, Ben-Dor et al. 2000, Alizadeh et al. 2000). However, the simultaneous classification across a heterogeneous set of tumor types has not been well studied yet. We obtained 190 samples from 14 tumor classes and generated a combined expression dataset containing 16063 genes for each of those samples. We performed multi-class classification by combining the outputs of binary classifiers. Three binary classifiers (k-nearest neighbors, weighted voting, and support vector machines) were applied in conjunction with three combination scenarios (one-vs-all, all-pairs, hierarchical partitioning). We achieved the best cross validation error rate of 18.75% and the best test error rate of 21.74% by using the one-vs-all support vector machine algorithm. The results demonstrate the feasibility of performing clinically useful classification from samples of multiple tumor types.

Algorithms↗
PubMed2001

[Trying to preserve the integrity of the family unit: the family living with the experience of having a child in the pediatric intensive care unit].

The purposes of this study were to: understand the dynamic functioning of the family with a child admitted to a pediatric intensive care unit (PICU) and to construct a theoretical model about the living experience of a family with a child admitted to the PICU. The study used as a theoretical reference the Symbolic Interactionism, and the Grounded theory methodology. The comparative analysis of the data permitted identify two phenomena: Having a family rupture and Living with the possibility of loosing a child. The relationship of these phenomena has permitted the identification of the core category TRYING TO PRESERVE THE INTEGRITY OF THE FAMILY UNIT based on which it was possible to propose a theoretical model to explain the experience.

Child↗
PubMed2001

[Living the inexorability of time and its changes with losses and possibilities: women in climacteric].

This research deals with the experience of women in climacterium. Symbolic interactionism and Grounded Theory were the theoretical and methodological framework of the study. Its objectives were to understand: how the experience of the climacterium is defined by the women; what were the psychosocial processes of interaction lived by the women; and to develop a theoretical model representing the experience of the women in climacterium. The strategies used to collect the data were participant observation and open ended interviews. The subjects were women in the age group of 45 to 60. The sample was of 30 women. The study revealed that the climacterium experience may be constituted of two phenomena: REJECTING CHANGES which is characterized by the women as a moment of loss and TRYING TO COPE WITH CHANGES, which represents the moment construction of new concepts with possibilities of reconstruction of life. Supported by these two phenomena, the central category was generated: LIVING THE INEXORABILITY OF TIME AND ITS CHANGES WITH LOSSES AND POSSIBILITIES which is fundamental to the generation of the theoretical model representing the experience of women in climacterium.

Climacteric↗
PubMed2000

Hyperhomocyst(e)inemia induces multiorgan damage.

Hyperhomocyst(e)inemia has been associated with the development of hypertension, stroke, and cardiovascular, cerebral/neuronal, renal, and liver diseases. To test the hypothesis that homocyst(e)ine plays an integrated role in multiorgan injury in hypertension, we employed: (1) spontaneously hypertensive rats (SHR) in which endogenous homocyst(e)ine levels are moderately high (18.1 +/- ().5 microM); (2) control age- and sex-matched Wistar Kyoto (WKY) rats in which homocyst(e)ine levels are normal (3.7 +/- 0.3 microM). To create the pathophysiological condition of hyperhomocyst(e)inemia, 20 mg/day homocyst(e)ine was administered for 12 weeks in (3) SHR (SHR-H) and in (4) WKY (WKY-H) rats. (5) Endogenous homocyst(e)ine levels were reduced slightly but not significantly from 18.1 +/- 0.5 microM to 12.5 +/- 0.7 microM in SHR by folic acid administration (SHR-F). Plasma and tissue levels of homocyst(e)ine were determined by HPLC and spectrophotometric methods. Plasma and sympathetic ganglion (neuronal) matrix metalloproteinase (MMP) activity was measured by zymography. Activity of neuronal MMP was increased in hyperhomocyst(e)inemic rats as compared with controls. Mean arterial pressure (mmHg) was 95 +/- 5, 126 +/- 8,157 +/- 10, 188 +/- 5, and 165 +/- 12 in WKY, WKY-H, SHR, SHR-H, and SHR-F, respectively. Urinary protein (mg/day) was 0.11 +/- 0.03, 0.88 +/- 0.22, 0.47 +/- 0.10, 0.89 +/- 0.21, and 0.81 +/- 0.21 in WKY, WKY-H. SHR, SHR-H, and SHR-F, respectively, as measured by the Bio-Rad dye binding assay. The relationships between increased arterial pressure, plasma homocyst(e)ine, and urinary protein were delineated. Plasma and neuronal creatinine phosphokinase (CK) isoenzymes were measured by agarose gel electrophoresis. All three CK isoenzymes, i.e., MM, MB, and BB, specific for skeletal, cardiac, and nerve tissue, respectively, were induced following 12 weeks' hyperhomocyst(e)inemia, suggesting multiorgan injury by homocyst(e)ine. Homocyst(e)ine induces endocardial endothelial cell (capillary) apoptosis and may reduce capillary cell density. Structural damage to aorta, myocardium, kidney, and renalureter was analyzed by histology. Results suggested an integrated physiological role of homocyst(e)ine in injury to the endothelial/epithelial cell lining in the respective organs.

Animals↗
PubMed2000

The Caenorhabditis elegans dosage compensation machinery is recruited to X chromosome DNA attached to an autosome.

The dosage compensation machinery of Caenorhabditis elegans is targeted specifically to the X chromosomes of hermaphrodites (XX) to reduce gene expression by half. Many of the trans-acting factors that direct the dosage compensation machinery to X have been identified, but none of the proposed cis-acting X chromosome-recognition elements needed to recruit dosage compensation components have been found. To study X chromosome recognition, we explored whether portions of an X chromosome attached to an autosome are competent to bind the C. elegans dosage compensation complex (DCC). To do so, we devised a three-dimensional in situ approach that allowed us to compare the volume, position, and number of chromosomal and subchromosomal bodies bound by the dosage compensation machinery in wild-type XX nuclei and XX nuclei carrying an X duplication. The dosage compensation complex was found to associate with a duplication of the right 30% of X, but the complex did not spread onto adjacent autosomal sequences. This result indicates that all the information required to specify X chromosome identity resides on the duplication and that the dosage compensation machinery can localize to a site distinct from the full-length hermaphrodite X chromosome. In contrast, smaller duplications of other regions of X appeared to not support localization of the DCC. In a separate effort to identify cis-acting X recognition elements, we used a computational approach to analyze genomic DNA sequences for the presence of short motifs that were abundant and overrepresented on X relative to autosomes. Fourteen families of X-enriched motifs were discovered and mapped onto the X chromosome.

Animals↗
PubMed2000

[The meaning of child and family care in the community: the learning experience of nursing students].

This present study, by applying qualitative research under a phenomenological perspective, attempts to seek an understanding of the meaning of the learning experiences of nursing students who care for child and family in the community. The data have been obtained through individual open interviews with nine students. Two themes have emerged from the analysis of the data: FACING CHALLENGES and GENERATING A NEW VIEW. Applying the theoretical approach of Viktor Frankl's existential analysis allows us to understand that what mobilizes students when facing challenges is the search for knowledge and desire to do something. Moreover, this study allows a reflection about significant learning in nursing, generating a new view as a consequence to the student feelings, thoughts and actions in the promotion of the personal and professional growth.

Child↗
PubMed2000

[Experiencing a difficult and revealing passage with her hospitalized child--a live-in mother's experience].

This study was conducted with live-in mother in university hospital. The objectives were as follows: to understand the experienced interactions, to identify the meanings that a family attribute to the experience of going through the child's hospitalization, to identify what the experience of hospitalization provokes in the family life and construct a model theory representative of the experience. Reference Theory the Symbolic Interactionism and Reference Methodology Grounded Theory had been utilized. From results appeared the phenomenon Going in search of solution and Going through a difficult situation. Through these phenomena, the main category Experiencing a difficult and revealing passage with her child was identified.

Child↗
PubMed2000

[Clinical experience of nursing students: transition of identities].

The purpose of this article is to describe nursing students clinical experience in the Maternal-Child and Psychiatric Nursing Department of the School of Nursing of the University of São Paulo (EEUSP). This activity has been implemented since 1996, not only to follow the demands of the Minimum Curriculum in Nursing, but also to give consistency to one of the purposes of the new curriculum of the EEUSP. This new purpose is concentrates on the facilitation of the transition process from being a student to being professional. The authors describe the experience of those involved in the process-Undergraduate student, faculty members and nurses making some considerations, regarding the results that demonstrate development of autonomy and responsibility in the future professional.

Career Mobility↗
PubMed1999

[Using tools for pain perception assessment in hospitalized pre-school children undergoing painful procedures].

The aim of this study was evaluate the utilization of tools for pain perception assessment in 41 hospitalized pre-school children submitted to painful procedures: care of wounds or blood extraction. The utilized tools were the faces scale, behavioral indicators and words which describe the pain. Most of the pre-schoolers understood and correctly answered to the faces scale, which can be noticed by the crescent movement 0 (no pain) 4 (maximum pain) during the choice of faces before and after the painful procedure. Crying, immortality and forehead wrinkling were the predominant behavioral indicators, intensified during the procedure. Pre-schoolers verbalizations about their pain showed up to be concrete terms or evaluative-indicative nature, resulting in variable or weakly precise concepts.

Age Factors↗
PubMed1999

[Hoping for the future child: the father's experience in the intensive care unit].

This study was intended to analyse the experience of the father who have a child in an Intensive Care Unit, by applying the qualitative research under the phenomenological perspective of Martin Heidegger, it was to identify three themes which figured that experience: Transforming the fear into hope, Perceiving himself as the person who decides and Acting for his child benefit. These themes unveiled the phenomenon SEARCHING A CHANCE FOR THE CHILD TO BECOME, who reveals that submits his child to risks and to essential treatments while continuously unchanging overcomes his own feelings in order to offer to his child an opportunity of full living.

Adaptation, Psychological↗
PubMed1999

[Family organization regarding children care: mothers' perception in a low income community].

The purposes of this study are to understand the perception that the mothers from a low income community in São Paulo city have about the meaning of their role in the family structure, concerning children care and the strategies used in family organization to carry out this care. The ethnographic analysis allowed us to identify 6 cultural domains and results showed that the mother have a main role in the family. They are the great responsible for the education, raising and socialization of the children. The adaptation of their role is characterized by their attention regarding to children needs. However, when they face children's growth, they show insecurity.

Adult↗
PubMed1998

[Meaning of the health concept from the perspective of families at personal and social risk].

The purpose of this study is to describe the meaning of health through the perspective of families under personal and social risk situations. The ethnographic analysis based the investigation and data were collected through interviews with the low income families of children attended by a Communitary Center in São Paulo city. The analysis of the interview contents allowed the identification of 7 cultural domains. The results of this study show the characteristics of knowledge, values and behaviours about the health concept, that are relevant to families, enabling the understanding of the family organization, that is significant to health care of each member and also the central role carried out by mothers in the studied culture.

Adult↗
PubMed1995

[From experience to science: the evolution of nursing knowledge].

The aim of this paper is to show the evolution of the nursing knowledge. Some relations with the nursing history are proposed, in order to indicate the ways the people and ideas of today in nursing was influenced by the past. The authors make a correlation between the development of the nursing as profession and of the nurse as professional.

Education, Nursing↗