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1.
Gynecol Obstet Fertil Senol ; 49(4): 246-254, 2021 04.
Artigo em Francês | MEDLINE | ID: mdl-33429111

RESUMO

OBJECTIVES: Iron deficiency anemia represents a public health issue which is usually managed by midwives. Because it is associated with maternal and fetal risks, a treatment is warranted. Oral iron represents the main option for treating this condition. Despite the existence of national and international guidelines no consensus about its modality of use has emerged so far. The primary objective of this study was to analyze midwives'practice with regards to iron deficiency anemia treatment using oral iron formulations. METHODS: We conducted an observational and descriptive cross-sectional in a sample of midwives from the Gironde administrative region using a questionnaire. RESULTS: We obtained 85 questionnaires from midwives working in private or public health facilities. Doses of iron and duration of treatment seem insufficient for a majority of responders. Folic acid and vitamin C are often associated with oral iron. Most midwives assess the efficacy of oral iron at one month with hemoglobin and ferritin levels. A significant fraction of these midwives shares similar practices which are in good accordance with the literature such as patient counselling with regards to drug intake, management of gastrointestinal side effects and inefficacity of oral iron. Noticeably, some of these midwives don't follow any guidelines. CONCLUSION: The majority of participants demonstrated practices in accordance with various national guidelines although no precise therapeutic algorithm is available as reference. Larger studies on the management of iron deficiency anemia in pregnancy by health professionals and harmonization of practices are necessary.


Assuntos
Anemia Ferropriva , Tocologia , Complicações Hematológicas na Gravidez , Anemia Ferropriva/tratamento farmacológico , Estudos Transversais , Feminino , Humanos , Ferro , Gravidez , Complicações Hematológicas na Gravidez/tratamento farmacológico
2.
Oncogene ; 29(33): 4636-47, 2010 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-20543869

RESUMO

Malignant glioma invasion is a primary cause of brain cancer treatment failure, yet the molecular mechanisms underlying its regulation remain elusive. We developed a novel functional-screening strategy and identified downregulated in renal cell carcinoma (DRR) as a regulator of invasion. We show that DRR drives invasion in vitro and in vivo. We found that while DRR is not expressed in normal glial cells, it is highly expressed in the invasive component of gliomas. Exploring underlying mechanisms, we show that DRR associates with and organizes the actin and microtubular cytoskeletons and that these associations are essential for focal adhesion (FA) disassembly and cell invasion. These findings identify DRR as a new cytoskeletal crosslinker that regulates FA dynamics and cell movement.


Assuntos
Neoplasias Encefálicas/patologia , Adesão Celular/fisiologia , Adesões Focais/patologia , Glioma/patologia , Proteínas Nucleares/metabolismo , Animais , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Adesão Celular/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Movimento Celular/fisiologia , Citoesqueleto/genética , Citoesqueleto/metabolismo , Citoesqueleto/fisiologia , Adesões Focais/genética , Adesões Focais/metabolismo , Genes Supressores de Tumor , Glioma/genética , Glioma/metabolismo , Humanos , Camundongos , Ratos
3.
Oncogene ; 25(37): 5103-12, 2006 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-16636676

RESUMO

Invasion of brain tumor cells has made primary malignant brain neoplasms among the most recalcitrant to therapeutic strategies. We tested whether the secreted protein Slit2, which guides the projection of axons and developing neurons, could modulate brain tumor cell invasion. Slit2 inhibited the invasion of medulloblastoma cells in a variety of in vitro models. The effect of Slit2 was inhibited by the Robo ectodomain. Time-lapse videomicroscopy indicated that Slit2 reduced medulloblastoma invasion rate without affecting cell direction or proliferation. Both medulloblastoma and glioma tumors express Robo1 and Slit2, but only medulloblastoma invasion is inhibited by recombinant Slit2 protein. Downregulation of activated Cdc42 may contribute to this differential response. Our findings reinforce the concept that neurodevelopmental cues such as Slit2 may provide insights into brain tumor invasion.


Assuntos
Meduloblastoma/patologia , Invasividade Neoplásica/prevenção & controle , Proteínas do Tecido Nervoso/fisiologia , Animais , Astrocitoma/genética , Astrocitoma/patologia , Neoplasias Encefálicas/patologia , Divisão Celular/efeitos dos fármacos , Neoplasias Cerebelares/genética , Neoplasias Cerebelares/patologia , Técnicas de Cocultura , Meios de Cultivo Condicionados , Glioma/patologia , Humanos , Peptídeos e Proteínas de Sinalização Intercelular , Cinética , Meduloblastoma/genética , Camundongos , Microscopia de Vídeo , Proteínas do Tecido Nervoso/genética , RNA Neoplásico/genética , RNA Neoplásico/isolamento & purificação , Receptores Imunológicos/genética , Receptores Imunológicos/fisiologia , Proteínas Recombinantes/farmacologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas , Proteínas Roundabout
4.
Oncogene ; 25(35): 4880-9, 2006 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-16532024

RESUMO

Many if not most tissues need a controlled number of stem cells to maintain normal function. Cancer can be seen as a process of disturbed tissue homeostasis, in which too many cells have or acquire too primitive identity. Here we measured how oncogenes and tumour suppressors affect the differentiation capacity, proportion and characteristics of progenitor cells in a model tissue. Neural progenitor cells (NPCs) were exposed to human papilloma virus E6, E7 or E6/E7 oncogenes, which degrade tumour suppressors p53 and pRb family members, respectively. E6/E7-expressing or p53-/- NPCs were able to differentiate, but simultaneously retained high capacity for self-renewal, proliferation, ability to remain multipotent in conditions promoting differentiation and showed delayed cell cycle exit. These functions were mediated through p53 and pRb family, and involved MEK-ERK signalling. Decreased amount of p53 increased self-renewal and proliferation, whereas pRb affected only proliferation. Our results suggest that the oncogenes increase whereas p53 and pRb family tumour suppressors decrease the number and proportion of progenitor cells. These findings provide one explanation how oncogenes and tumour suppressors control tissue homeostasis and highlight their importance in stem cell self- renewal, linked both to cancer and life-long tissue turnover.


Assuntos
Genes Supressores de Tumor , Neurônios/citologia , Proteínas Oncogênicas Virais/genética , Proteínas Repressoras/genética , Células-Tronco/fisiologia , Animais , Diferenciação Celular/fisiologia , Divisão Celular/genética , Células Cultivadas , Camundongos , Proteínas Oncogênicas Virais/fisiologia , Proteínas E7 de Papillomavirus , Proteínas Repressoras/fisiologia
5.
J Virol ; 73(9): 7703-9, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10438860

RESUMO

Three monoclonal antibodies (MAbs) generated against rainbow trout gonad cells (RTG-2) have been selected for their ability to protect cells from the viral hemorrhagic septicemia virus (VHSV) infection, a salmonid rhabdovirus. Protection from infection was restricted to the salmonid-derived cell lines indicating species specificity of the blocking MAbs. Surprisingly, the blocking activity of these MAbs was also effective against other nonantigenically related fish rhabdoviruses. Indirect immunofluorescence and immunoelectron microscopy observations demonstrated that the three MAbs were all directed against an abundant cell plasma membrane component, and immunoprecipitation studies indicated that the target consisted of a heterodimeric complex with molecular masses of 200 and 44 kDa. Biochemical data provided the following evidence that fibronectin is part of this complex and that it could represent the main receptor for fish rhabdoviruses. (i) An antiserum generated against the 200-kDa protein reacted against the recombinant rainbow trout fibronectin expressed in Escherichia coli. (ii) The purified rainbow trout fibronectin was able to bind specifically to VHSV. To our knowledge, this is the first identification of a cellular component acting as a primary receptor for a virus replicating in lower vertebrates and, more interestingly, for viruses belonging to the Rhabdoviridae family.


Assuntos
Fibronectinas/metabolismo , Receptores Virais/metabolismo , Rhabdoviridae/metabolismo , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/metabolismo , Linhagem Celular , Membrana Celular/metabolismo , Fibronectinas/genética , Camundongos , Dados de Sequência Molecular , Oncorhynchus mykiss , Receptores Virais/genética , Rhabdoviridae/fisiologia , Salmonidae/virologia , Células Tumorais Cultivadas
6.
J Cell Biol ; 144(5): 1019-31, 1999 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-10085298

RESUMO

In this article, we show that, in transfected COS-1 cells, protein tyrosine phosphatase (PTP)-PEST translocates to the membrane periphery following stimulation by the extracellular matrix protein fibronectin. When plated on fibronectin, PTP-PEST (-/-) fibroblasts display a strong defect in motility. 3 h after plating on fibronectin, the number and size of vinculin containing focal adhesions were greatly increased in the homozygous PTP-PEST mutant cells as compared with heterozygous cells. This phenomenon appears to be due in part to a constitutive increase in tyrosine phosphorylation of p130(CAS), a known PTP-PEST substrate, paxillin, which associates with PTP-PEST in vitro, and focal adhesion kinase (FAK). Another effect of this constitutive hyperphosphorylation, consistent with the focal adhesion regulation defect, is that (-/-) cells spread faster than the control cell line when plated on fibronectin. In the PTP-PEST (-/-) cells, an increase in affinity for the SH2 domains of Src and Crk towards p130(CAS) was also observed. In (-/-) cells, we found a significant increase in the level of tyrosine phosphorylation of PSTPIP, a cleavage furrow-associated protein that interacts physically with all PEST family members. An effect of PSTPIP hyperphosphorylation appears to be that some cells remain attached at the site of the cleavage furrow for an extended period of time. In conclusion, our data suggest PTP-PEST plays a dual role in cell cytoskeleton organization, by promoting the turnover of focal adhesions required for cell migration, and by directly or indirectly regulating the proline, serine, threonine phosphatase interacting protein (PSTPIP) tyrosine phosphorylation level which may be involved in regulating cleavage furrow formation or disassembly during normal cell division.


Assuntos
Moléculas de Adesão Celular/metabolismo , Ciclo Celular , Movimento Celular , Proteínas Tirosina Fosfatases/metabolismo , Proteínas Tirosina Quinases/metabolismo , Animais , Células COS , Membrana Celular/enzimologia , Citoplasma/enzimologia , Proteínas do Citoesqueleto/metabolismo , Fibroblastos/citologia , Fibroblastos/enzimologia , Fibronectinas/metabolismo , Proteína-Tirosina Quinases de Adesão Focal , Paxilina , Fosfoproteínas/metabolismo , Fosforilação , Proteína Tirosina Fosfatase não Receptora Tipo 12 , Domínios de Homologia de src
7.
Biochem Cell Biol ; 77(6): 493-505, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10668627

RESUMO

Signal transduction pathways are often seen as cascades of kinases, whereas phosphatases are relinquished to the housekeeping function of resetting the individual elements to a resting state. However, critical biological processes such as cellular migration require a coordinated and constant remodeling of the actin cytoskeleton as well as a rapid turnover of the cell-substratum linkages that necessitate the concomitant action of antagonistic enzymes. Tyrosine phosphorylation was long known to be involved in adhesion and de-adhesion mediated via the integrin receptors. As the roles of tyrosine kinases such as focal adhesion kinase, c-Src, and Csk in this pathway are being extensively studied, increasing evidence is emerging about the importance of protein tyrosine phosphatases (PTP). In this review we discuss examples of PTPs that were recently shown to play a role in cell adhesion and migration and their mechanism of action.


Assuntos
Movimento Celular/fisiologia , Proteínas Tirosina Fosfatases/metabolismo , Tirosina/metabolismo , Animais , Adesão Celular/fisiologia , Fosforilação
9.
J Nurs Educ ; 31(4): 175-80, 1992 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1317413

RESUMO

Twenty-one students in their first quarter of nursing school were interviewed to determine the utility of the typology for ways of knowing developed by Belenky, Clinchy, Goldberger, and Tarule (1986) for understanding the cognitive development of nursing students; the differences in epistemological perspectives by gender, age, and ethnicity; and the forces in nursing school that encourage developmental transitions. The typology was found to be applicable for Caucasian women and provided important insights on differences among groups of students. Some of the implications for providing supportive educational environments are presented.


Assuntos
Cognição , Aprendizagem , Modelos Psicológicos , Socialização , Estudantes de Enfermagem/psicologia , Adulto , Fatores Etários , Autoritarismo , Bacharelado em Enfermagem/normas , Feminino , Objetivos , Desenvolvimento Humano , Humanos , Masculino , Pessoa de Meia-Idade , Grupos Minoritários , Pesquisa em Educação em Enfermagem , Papel (figurativo) , Autoimagem , Caracteres Sexuais , Washington
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