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1.
iScience ; 25(3): 103884, 2022 Mar 18.
Article de Anglais | MEDLINE | ID: mdl-35243244

RÉSUMÉ

Advances in regenerative medicine have led to the construction of many types of organoids, which reproduce important aspects of endogenous organs but may be limited or disorganized in nature. While their usefulness for restoring function remains unclear, they have undoubted usefulness in research, diagnostics, and toxicology. In toxicology, there is an urgent need for better models for human kidneys. We used human iPS-cell (hiPSC)-derived renal organoids to identify HMOX1 as a useful marker of toxic stress via the oxidative stress pathway, and then constructed an HMOX1 reporter in hiPSCs. We used two forms of hiPSC-derived HMOX1-reporter renal organoids to probe their ability to detect nephrotoxicants in a panel of blind-coded compounds. Our results highlight the potential usefulness, and some limitations, of HMOX1-reporter renal organoids as screening tools. The results may guide development of similar stress-reporting organoid assays for other stem-cell-derived organs and tissues.

2.
Allergy ; 67(6): 831-3, 2012 Jun.
Article de Anglais | MEDLINE | ID: mdl-22515200

RÉSUMÉ

Monozygotic (MZ) twins discordant for complex diseases may help to find disease mechanisms that are not due to genetic variants. Intermittent allergic rhinitis (IAR) is an optimal disease model because it occurs at defined time points each year, owing to known external antigens. We hypothesized that MZ twins discordant for IAR could help to find gene expression differences that are not dependent on genetic variants. We collected blood outside of the season from MZ twins discordant for IAR, challenged their peripheral blood mononuclear cells (PBMC) with pollen allergen in vitro, collected supernatants and isolated CD4+ T cells. We identified disease-relevant mRNAs and proteins that differed between the discordant MZ twins. By contrast, no differences in microRNA expression were found. Our results indicate that MZ twins discordant for IAR is an optimal model to identify disease mechanisms that are not due to genetic variants.


Sujet(s)
Maladies chez les jumeaux/génétique , Analyse de profil d'expression de gènes , ARN messager/analyse , Rhinite allergique saisonnière/génétique , Jumeaux monozygotes/génétique , Maladies chez les jumeaux/immunologie , Humains , Séquençage par oligonucléotides en batterie , Protéines/analyse , RT-PCR , Rhinite allergique saisonnière/immunologie
4.
Scand J Surg ; 97(3): 248-53, 2008.
Article de Anglais | MEDLINE | ID: mdl-18812275

RÉSUMÉ

BACKGROUND AND AIMS: Differentiation between the two major subgroups of primary aldosteronism, bilateral hyperplasia and aldosterone producing adenoma is essential since therapy in the former is medical and in the latter surgical. The aim of the present study was to evaluate the clinical utility of adrenocortical scintigraphy in the management of primary aldosteronism. MATERIAL AND METHODS: [131I] norcholesterol (NP-59) scintigraphy with dexamethasone suppression for subclassification and lateralization of primary aldosteronism was evaluated in 49 patients with long-term follow-up after diagnosis and treatment. RESULTS: Thirty-three patients with the diagnosis of aldosterone producing adenoma were operated with adrenalectomy. Preoperative scintigraphy showed lateralized isotope uptake in 27/33 patients while 6 showed no uptake. Twenty-two were cured and three significantly improved. Thus, in 25/33 (76%), scintigraphy showed the correct side as the patients benefited of surgery. Two patients did not improve. Fourteen patients with a probable diagnosis of bilateral hyperplasia had normal scintigraphies. CONCLUSIONS: In the present retrospective study we found limited sensitivity of NP-59 scintigraphy. However, when a lateralized scintigraphic uptake is achieved it has a high accuracy. Scintigraphy may be used as an adjunct in cases where adrenal venous sampling is inconclusive.


Sujet(s)
Glandes surrénales/imagerie diagnostique , Surrénalectomie/méthodes , Hyperaldostéronisme/imagerie diagnostique , Soins préopératoires/méthodes , Adolescent , Adulte , Sujet âgé , Diagnostic différentiel , Femelle , Études de suivi , Humains , Hyperaldostéronisme/chirurgie , Mâle , Adulte d'âge moyen , Scintigraphie , Études rétrospectives , Facteurs temps , Jeune adulte
5.
J Appl Microbiol ; 103(2): 487-98, 2007 Aug.
Article de Anglais | MEDLINE | ID: mdl-17650210

RÉSUMÉ

AIMS: This study investigates changes in microbiological and physicochemical parameters during large-scale, thermophilic composting of a single batch of municipal organic waste. The inter-relationships between the microbial biomass and community structure as well as several physicochemical parameters and estimates of maturation were evaluated. METHODS AND RESULTS: Analyses of signature fatty acids with the phospholipid fatty acid and ester-linked methods showed that the total microbial biomass was highest during the early thermophilic phase. The contribution of signature 10Me fatty acids from Actinobacteria indicated a relatively constant proportion around 10% of the microbial community. However, analyses of the Actinobacteria species composition with a PCR-denaturing gradient gel electrophoresis approach targeting 16S rRNA genes demonstrated clear shifts in the community structure. CONCLUSIONS: This study demonstrates that compost quality, particularly maturity, is linked to the composition of the microbial community structure, but further studies in other full-scale systems are needed to validate the generality of these findings. SIGNIFICANCE AND IMPACT OF THE STUDY: The combination of signature lipid and nucleic acid-based analyses greatly expands the specificity and the scope for assessing the microbial community composition in composts. The results presented in this study give new information on how the development of the compost microbial community is connected to curing and maturation in the later stages of composting, and emphasizes the role of Actinobacteria in this respect.


Sujet(s)
Actinobacteria/isolement et purification , Substances humiques/microbiologie , Microbiologie du sol , Déchets , Actinobacteria/génétique , Actinobacteria/métabolisme , Dépollution biologique de l'environnement , Biomasse , ADN bactérien/analyse , Électrophorèse sur gel de polyacrylamide/méthodes , Acides gras/analyse , Produits domestiques/microbiologie , Lipides/analyse , Phospholipides/analyse , Phylogenèse , Analyse en composantes principales , Élimination des déchets/méthodes , Sol/analyse , Déchets/analyse
6.
Eur J Clin Microbiol Infect Dis ; 23(3): 208-11, 2004 Mar.
Article de Anglais | MEDLINE | ID: mdl-14986162

RÉSUMÉ

In order to detect immunoglobulin (Ig)A and IgG antibodies to Escherichia coli-secreted protein B in sera of children infected with Shiga toxin-producing Escherichia coli, an enzyme-linked immunosorbent assay was developed. The assay was tested using acute sera from 40 children with diarrhea-associated hemolytic uremic syndrome compared with 238 sera obtained from pediatric controls. Two cut-off values were used for children <5 (n=27) or > or =5 (n=13) years of age. Among the younger patients, 24 of 27 had IgA antibodies to Escherichia coli-secreted protein B (sensitivity, 89%; specificity, 98%) and 22 of 27 had IgG antibodies (sensitivity, 82%; specificity, 94%). Among the older patients, 13 of 13 had IgA antibodies (sensitivity, 100%; specificity, 96%) and 11 of 13 had IgG antibodies (sensitivity, 85%; specificity, 96%). This enzyme-linked immunosorbent assay detects Shiga-toxin-producing Escherichia coli independent of serogroup and could serve as a complementary assay for detection of infection.


Sujet(s)
Anticorps antibactériens/analyse , Test ELISA , Infections à Escherichia coli/diagnostic , Escherichia coli/isolement et purification , Syndrome hémolytique et urémique/immunologie , Shiga-toxine/immunologie , Anticorps antibactériens/immunologie , Protéines bactériennes/immunologie , Protéines bactériennes/métabolisme , Études cas-témoins , Enfant , Enfant d'âge préscolaire , Escherichia coli/immunologie , Femelle , Syndrome hémolytique et urémique/diagnostic , Humains , Immunoglobuline A/analyse , Immunoglobuline A/immunologie , Immunoglobuline G/analyse , Immunoglobuline G/immunologie , Mâle , Probabilité , Valeurs de référence , Sensibilité et spécificité , Shiga-toxine/analyse
7.
Reprod Biomed Online ; 5(1): 36-8, 2002.
Article de Anglais | MEDLINE | ID: mdl-12470543

RÉSUMÉ

An observation is reported of internalization of a cellular fragment into a blastomere from a human embryo, as documented by time-lapse photography. The fragment, created during the first mitotic cleavage was reabsorbed into one of the mother blastomeres in less than 5 min. The time-lapse sequence, shown here as a series of still photographs, provides the first direct evidence that cellular fragments in human embryos can 'disappear' during the culture period, a phenomenon that is common in human IVF. The time-lapse sequence itself may be viewed on the internet at www.rbmonline.com/Article/633.


Sujet(s)
Blastomères/cytologie , Blastomères/physiologie , Endocytose , Techniques de culture , Conception d'appareillage , Humains , Mitose/physiologie , Photographie (méthode)/instrumentation , Photographie (méthode)/méthodes
8.
J Adv Nurs ; 34(5): 648-58, 2001 Jun.
Article de Anglais | MEDLINE | ID: mdl-11380733

RÉSUMÉ

AIMS AND BACKGROUND: The purpose of this follow-up study was to describe the development of reflective learning of 16 student nurses in the context of health counselling and promotion during clinical training of a 3-year nursing education programme in two Finnish polytechnics. The first aim was to analyse the levels of reflectivity in the student nurses' reflections on their videotaped counselling situations. The second aim was to explore the qualitative features of the reflective health counselling learning process in the context of health promotion. The theoretical background of the study was based on a transformative learning theory. METHODS: The data consisted of stimulated recall interviews with 16 student nurses conducted once a year between 1998 and 2000. The data were analysed using categorization and thematic analysis. FINDINGS: The findings of the study showed that half of the students in the research group reached the level of critical consciousness during their nursing education. The others remained at the level of consciousness. Two students who represented thoughtful action without reflection in the first study year were able to reach reflection and even critical reflection later during their education. The meaning schemas of counselling developed and were enriched when the students moved into the higher stages of reflection. There were features of an empowerment approach to health promotion only in the meaning schemas and perspectives of critical reflectors. CONCLUSIONS: These results may indicate that the empowerment approach to health promotion within the modern health promoting role of nurses requires critical reflection. Therefore, effective methods and evaluation tools of reflective learning are needed to support learning from practice via critical reflection.


Sujet(s)
Attitude du personnel soignant , Assistance/enseignement et éducation , Programme diplôme infirmier (USA)/organisation et administration , Promotion de la santé/méthodes , Démarche de soins infirmiers , Élève infirmier/psychologie , Pensée (activité mentale) , Adolescent , Adulte , Femelle , Finlande , Études de suivi , Humains , Apprentissage , Modèles éducatifs , Recherche en enseignement des soins infirmiers , Recherche en méthodologie des soins infirmiers , Pouvoir psychologique , Évaluation de programme , Enquêtes et questionnaires
9.
Qual Health Res ; 11(3): 399-422, 2001 May.
Article de Anglais | MEDLINE | ID: mdl-11339082

RÉSUMÉ

This study explored patients' taciturnity as observed on videotape during hospital health counseling situations with a nurse. Health counseling sessions, 38 in number, were videotaped, transcribed verbatim, and analyzed by using an adaptation of conversation analysis. The data analysis included information on 18 selected patients who spoke little and did not introduce new topics, but rather supported the discussion on the theme chosen by the nurse. When we examined nurses' and patients' speech word by word, we discovered four participation frames that produced taciturnity: in the hands of professionals, compliant, guilty, and polite. These could fluctuate during interaction. The findings indicate that there is a need for a more extensive description of taciturn, or silent, patients. What has been interpreted as passivity in the literature can be interpreted more constructively. This insight can be useful for developing health counseling practice in hospitals.


Sujet(s)
Assistance , Relations infirmier-patient , Personnel infirmier hospitalier , Participation des patients/psychologie , Adolescent , Adulte , Sujet âgé , Barrières de communication , Finlande , Humains , Adulte d'âge moyen , Enregistrement sur bande vidéo
10.
Blood ; 97(10): 3100-8, 2001 May 15.
Article de Anglais | MEDLINE | ID: mdl-11342436

RÉSUMÉ

Thrombocytopenia caused by platelet consumption in thrombi is a major manifestation of hemolytic uremic syndrome (HUS) associated with Shiga toxin (Stx) producing Escherichia coli. Platelets have glycosphingolipid receptors capable of binding Stx, but a direct interaction between the toxin and platelets, leading to platelet activation, has not been reported. In this study, it is shown that Stx1 and its B (binding) subunit (Stx1B), at 10 pg/mL to 10 ng/mL, bound to platelets. Toxin was internalized in platelets within 2 hours. This led to increased platelet aggregation, as demonstrated by confocal microscopy. Preincubation of Stx1B with anti-Stx1 antibody inhibited this reaction. Stx1 induced morphologic changes in platelets seen on scanning electron microscopy. In the presence of platelets and tumor necrosis factor-pretreated human umbilical vein endothelial cells (HUVEC), Stx1 and Stx1B induced the binding of platelets to the endothelial cell membrane and were present at this binding site. Incubation of Stx1 and Stx1B with whole blood increased fibrinogen binding to platelets detected by flow cytometry. Fibrinogen binding was partially inhibited by preincubation with anti-Stx1. Stx1 increased platelet retention measured in a glass bead assay. In addition, plasma from 17 patients with HUS, taken during the acute phase of the disease, increased the retention of normal platelets and normalized after recovery. Taken together, the results of this investigation show that Stx1, Stx1B, and a factor or factors in the plasma of patients with HUS activate platelets. The presence of Stx1 at the binding site of platelets to HUVEC suggests that Stx may be directly involved in the prothrombotic state seen in HUS.


Sujet(s)
Syndrome hémolytique et urémique/sang , Activation plaquettaire/effets des médicaments et des substances chimiques , Shiga-toxine/pharmacologie , Adolescent , Plaquettes/métabolisme , Plaquettes/ultrastructure , Enfant , Enfant d'âge préscolaire , Endothélium vasculaire/physiologie , Escherichia coli/métabolisme , Infections à Escherichia coli/sang , Femelle , Fibrinogène/métabolisme , Syndrome hémolytique et urémique/microbiologie , Humains , Nourrisson , Mâle , Shiga-toxine/métabolisme , Shiga-toxine-1/métabolisme , Shiga-toxine-1/pharmacologie , Shiga-toxine-2/métabolisme , Shiga-toxine-2/pharmacologie , Facteur de nécrose tumorale alpha/pharmacologie , Veines ombilicales
11.
Leukemia ; 15(5): 716-27, 2001 May.
Article de Anglais | MEDLINE | ID: mdl-11368431

RÉSUMÉ

The analysis of minimal residual disease (MRD) has assumed a growing role in the follow-up of patients with acute lymphoblastic leukemia (ALL). We have applied multiparameter flow cytometry (FC) with 'live-gate' analysis and allele-specific oligonucleotide (ASO)-PCR detecting leukemia-specific T cell receptor gamma and delta gene rearrangements for MRD follow-up in 30 ALL patients. The comparison of results obtained in 89 follow-up samples from 23 patients showed significantly consistent results in 70 samples (78%); (P < 0.001). Bone marrow samples taken during the first phase of treatment (during or immediately after induction) showed a lower level of consistency when compared to samples taken during later phases of treatment (69% vs 85% consistent results, respectively). Some of the discrepant results were due to low cellularity of the samples obtained for FC and some due to the presence of PCR inhibitors. Of 29 patients evaluated at the end of the induction treatment, 18 (62%) had detectable levels of MRD and six of these patients suffered relapse. In all these patients MRD levels by FC increased preceding relapse. Our results suggest that FC offers a MRD detection tool that can be easily applied in clinical practice and is as informative as molecular methods.


Sujet(s)
Allèles , Cytométrie en flux , Réaction de polymérisation en chaîne , Leucémie-lymphome lymphoblastique à précurseurs B et T/diagnostic , Adolescent , Adulte , Enfant , Enfant d'âge préscolaire , Femelle , Humains , Mâle , Maladie résiduelle
12.
Health Educ Res ; 16(1): 33-48, 2001 Feb.
Article de Anglais | MEDLINE | ID: mdl-11252282

RÉSUMÉ

This article describes student nurses' constructions of health promotion and the change of these constructions during their nursing education in two Finnish polytechnics. The data consisted of essays written by the 19 student nurses before they began their nursing education in 1997 and of stimulated recall interviews with the same students during the second year of their education in 1998. The data were analyzed by using thematic analysis. During the first study year, 13 students' constructions of health promotion changed. Six students had initially broad constructions of health promotion and their constructions remained unchanged. Four basic changes were found in the students' constructions: (1) the emphasis shifted from physical to multidimensional health promotion, (2) health promotion became more concrete and contextual, (3) the conception of perfect health became more permissive and relative, and (4) the interpretation of health promotion shifted from performing towards being there for the patient. These results may indicate that student nurses in Finnish polytechnics were attempting to adopt the empowerment approach to health promotion for their constructions. Moreover, the results represent a major challenge concerning nursing education and health promotion learning from the constructivistic approach to knowledge building.


Sujet(s)
Enseignement infirmier , Promotion de la santé/organisation et administration , Élève infirmier/psychologie , Attitude du personnel soignant , Finlande , Humains , Entretiens comme sujet , Rappel mnésique
13.
Acta Obstet Gynecol Scand ; 80(4): 331-6, 2001 Apr.
Article de Anglais | MEDLINE | ID: mdl-11264608

RÉSUMÉ

BACKGROUND: A program for preimplantation genetic diagnosis of pre-embryos from patients with hereditary disorders was set up in our unit at Sahlgrenska University Hospital in 1994. The majority of the patients were carriers of X-chromosome linked disorders; a few patients were translocation carriers. In this paper we describe our experiences of our first 36 cycles, 30 gender determinations and six analyses of embryos with possible translocations. METHODS: Conventional hormone replacement treatment with intracytoplasmic sperm injection to fertilize the eggs followed by blastomere biopsy and fluorescent in situ hybridization at the eight cell stage was used for sexing as well as detection of translocations. RESULTS: Out of the 30 cycles in 13 patients for gender determination, blastomere biopsies could be carried out in 25 cycles. Transfer of normal female embryos (XX) was performed in 18 cycles, resulting in five pregnancies (pregnancy rate 27.8%) and an implantation rate of 20% per transfer. Three girls have been born. Hence the take home baby rate was 16.7% per transfer and 10% per started cycle. Six cycles (three patients) for detection of translocations in embryos were performed. Diagnosis was possible in four cycles. Transfer of normal embryos was carried out in one cycle. No pregnancy was achieved. CONCLUSION: Successful PGD in its clinical application demands close collaboration between a large group of specialists. Even so, the success rate is considerably lower than after conventional IVF or ICSI procedures. Taking into account the stress caused to the parents facing late interruption of pregnancy following conventional prenatal diagnosis we are convinced that this technique is well worthwhile continuing and refining.


Sujet(s)
Diagnostic préimplantatoire , Détermination du sexe , Translocation génétique , Analyse cytogénétique , Transfert d'embryon , Femelle , Humains , Hybridation fluorescente in situ , Mâle , Grossesse , Taux de grossesse , Suède
14.
Hum Reprod ; 16(2): 313-8, 2001 Feb.
Article de Anglais | MEDLINE | ID: mdl-11157826

RÉSUMÉ

Uneven blastomere cleavage in human embryos of 'good morphology', i.e. those normally used for transfer, is a phenomenon which has been poorly investigated. The main objective in this study was to probe deeper into the aetiology behind previous findings that embryos with uneven cell cleavage have a lower developmental capacity in comparison with evenly cleaved embryos. Our hypothesis was that uneven cleavage may result in embryos with a higher degree of aneuploidy and/or multinuclear rate, which in turn might help to explain their low implantation rate. In the first part of the study, 378 embryo transfers performed over a 3-year period were analysed retrospectively, where all the transferred embryos in each cycle were of identical morphology score and cleavage stage. In the second part of the study, multicolour fluorescence in-situ hybridization (FISH) analyses on good quality embryos, representing the uneven (n = 11) and even (n = 13) study groups were performed. When comparing day 2 transfers between 4-cell embryos, it was found that unevenly cleaved embryos had significantly lower implantation (23.9 and 36.4%) and pregnancy rates (37.6 and 52.9%) compared with evenly cleaved embryos. A significantly higher degree of aneuploidy (29.4 and 8.5%) and multinuclear rate (21.1 and 2.1%) in blastomeres from uneven embryos was also found. It is concluded that uneven blastomere cleavage has a negative effect on both pregnancy and implantation rates in human IVF, and that this can partly be explained by a higher degree of aneuploidy/multinuclear rate. In the light of the results obtained, a new approach in the current embryo scoring system, placing more emphasis on blastomere size, is recommended.


Sujet(s)
Aneuploïdie , Blastomères/cytologie , Transfert d'embryon , Développement embryonnaire et foetal , Adulte , Noyau de la cellule/génétique , Taille de la cellule , Implantation embryonnaire , Femelle , Fécondation in vitro , Humains , Hybridation fluorescente in situ , Mâle , Grossesse , Injections intracytoplasmiques de spermatozoïdes
15.
Anal Chem ; 73(3): 444-52, 2001 Feb 01.
Article de Anglais | MEDLINE | ID: mdl-11217744

RÉSUMÉ

Macroporous monoliths containing N,N-dimethyl-N-methacryloyloxyethyl-N-(3-sulfopropyl)ammonium betaine (SPE) have been synthesized via in situ photopolymerization, yielding a stoichiometric balance between sulfur and nitrogen in the final polymer, which is indicative of a genuine strong/strong zwitterionic character. The chromatographic properties of these zwitterionic resins were evaluated with respect to the retention behavior of inorganic ions and proteins. The weak electrostatic nature of the interaction between the sulfobetaine monoliths and proteins provided a high selectivity between basic proteins and peptides. Elution was accomplished with low-ionic-strength fully aqueous mobile phases, whereby high recovery was obtained, even for hydrophobic proteins. Chaotropic ions such as perchlorate or thiocyanate were used as mobile phase modifiers to modulate the apparent ion exchange group density, thus introducing a route for the modulation of the ionic strength that is required to competitively elute the protein. The promising features of polymeric sulfoalkylbetaine interaction layers for separation and analysis of biological extracts was also manifested in an application involving purification of biologically active peptide-pheromone obtained from Enterococcus faecium.

16.
Nurse Educ Today ; 20(8): 629-37, 2000 Nov.
Article de Anglais | MEDLINE | ID: mdl-11090310

RÉSUMÉ

The purpose of this study was to examine the manifestation of health promotion in two Finnish health care and nursing polytechnic curricula for students starting their studies in August 1997. Another goal was to explore students' and their teachers' perceptions of which modules contained health promotion, as well as to find out which modules contained integrated health promotion. In this study, data and investigator triangulation were used. The data consisted of the curricula of two polytechnics of health care and of interviews with 20 student nurses and their teachers. The data were analysed using content analysis. Health promotion studies were integrated with other studies in the curriculum of the first polytechnic, whereas the second polytechnic had two separate health promotion modules. While most students were in favour of separate health promotion modules, teachers supported integrated modules. Students also reported that their teachers integrated health promotion in modules which were not named as such, for example, in language modules. The results represent a major challenge concerning the content of health promotion in the curricula and, also, the methods for teaching health promotion. More cooperation between teachers during the process of planning curricula is recommended.


Sujet(s)
Programme d'études , Formation au diplôme infirmier (USA)/organisation et administration , Promotion de la santé , Finlande , Humains , Recherche en enseignement des soins infirmiers , Écoles d'infirmières/organisation et administration
17.
J Reprod Fertil ; 120(2): 337-50, 2000 Nov.
Article de Anglais | MEDLINE | ID: mdl-11058449

RÉSUMÉ

The interactions of seven human blastocysts with cultured endometrial cells were investigated by light microscopy and transmission electron microscopy. Trophoblastic-endometrial contact was observed at the lateral border of endometrial epithelial cells where trophoblast and endometrial epithelial cells shared apical junctional complexes and desmosomes. The first sign of penetration was invasion of a trophoblastic cytoplasmic protrusion between endometrial epithelial cells. In broad contact areas, lateral displacement of endometrial epithelial cells and formation of a peripheral pseudostratified epithelium were observed. When trophoblastic cells were interposed fully among endometrial epithelial cells, they formed a penetration cone and appeared to dislodge endometrial epithelial cells from the stromal compartment. A single penetration cone only was found in each specimen. Endometrial or trophoblastic degeneration was not observed. Formation of multinucleate (>/= three nuclei per cell) trophoblast cells was not observed, but many cells displayed areas with abrupt disappearance of well-defined plasma membranes, which is indicative of syncytium formation. In this study, adhesion and penetration occurred at the same time. The human blastocysts penetrated the endometrial surface epithelium by intrusive penetration. Epithelial penetration was achieved primarily by cellular syncytiotrophoblast-like cells and the first indications of syncytium formation were observed simultaneously with penetration of the epithelium.


Sujet(s)
Implantation embryonnaire/physiologie , Endomètre/ultrastructure , Trophoblastes/ultrastructure , Adhérence cellulaire/physiologie , Cellules cultivées , Endomètre/physiologie , Cellules épithéliales/physiologie , Cellules épithéliales/ultrastructure , Femelle , Humains , Microscopie électronique , Trophoblastes/physiologie
18.
Eur J Neurosci ; 12(10): 3675-86, 2000 Oct.
Article de Anglais | MEDLINE | ID: mdl-11029637

RÉSUMÉ

Vascular endothelial growth factor (VEGF) is an angiogenetic factor that promotes endothelial cell proliferation during development and after injury to various types of tissue, including the central nervous system (CNS). Using immunohistochemical and in situ hybridization methods we have here demonstrated that VEGF and its receptors Flk-1, Flt-1 and Neuropilin-1 mRNAs and proteins are induced after incisions in the rat spinal cord. The inducible enzyme for prostaglandin synthesis cyclooxygenase-2 (COX-2) is known to be upregulated after spinal injury, cerebral ischemia and to stimulate angiogenesis. To test the hypothesis that prostaglandins may be involved in the VEGF response after lesion we investigated whether intraspinal microinjections of prostaglandin F2alpha (PGF2alpha) alters VEGF expression in the spinal cord. Such treatment was followed by a strong upregulation of VEGF mRNA and protein in the injection area. Finally, by use of an in vitro model with cell cultures of meningeal fibroblast and astrocyte origin, resembling the lesion area cellular content after spinal cord injury but devoid of inflammatory cells, we showed that VEGF is expressed in this in vitro model cell system after treatment with PGF2alpha and prostaglandin E2 (PGE2). These data suggest that cells within a lesion area in the spinal cord are capable of expressing VEGF and its receptors in response to mechanical injury and that prostaglandins may induce VEGF expression in such cells, even in the absence of inflammatory cells.


Sujet(s)
Facteurs de croissance endothéliale/métabolisme , Lymphokines/métabolisme , Néovascularisation pathologique/physiopathologie , Prostaglandines/pharmacologie , Récepteurs à activité tyrosine kinase/métabolisme , Récepteur facteur croissance/métabolisme , Traumatismes de la moelle épinière/métabolisme , Moelle spinale/métabolisme , Animaux , Astrocytes/cytologie , Astrocytes/effets des médicaments et des substances chimiques , Astrocytes/métabolisme , Cellules cultivées , Cicatrice/traitement médicamenteux , Cicatrice/anatomopathologie , Cicatrice/physiopathologie , Facteurs de croissance endothéliale/génétique , Femelle , Foetus/cytologie , Foetus/effets des médicaments et des substances chimiques , Foetus/métabolisme , Fibroblastes/cytologie , Fibroblastes/effets des médicaments et des substances chimiques , Fibroblastes/métabolisme , Interféron gamma/métabolisme , Interféron gamma/pharmacologie , Lymphokines/génétique , Néovascularisation pathologique/traitement médicamenteux , Néovascularisation pathologique/anatomopathologie , Prostaglandines/métabolisme , ARN messager/métabolisme , Rats , Rat Sprague-Dawley , Récepteurs à activité tyrosine kinase/génétique , Récepteur facteur croissance/génétique , Récepteurs aux facteurs de croissance endothéliale vasculaire , Moelle spinale/effets des médicaments et des substances chimiques , Moelle spinale/anatomopathologie , Moelle spinale/physiopathologie , Traumatismes de la moelle épinière/traitement médicamenteux , Traumatismes de la moelle épinière/anatomopathologie , Traumatismes de la moelle épinière/physiopathologie , Facteur de croissance transformant bêta/métabolisme , Facteur de croissance transformant bêta/pharmacologie , Facteur de croissance endothéliale vasculaire de type A , Facteurs de croissance endothéliale vasculaire
19.
Hum Reprod ; 14(2): 515-20, 1999 Feb.
Article de Anglais | MEDLINE | ID: mdl-10100003

RÉSUMÉ

In order to study changes occurring on the surfaces of human endometrial epithelial cells in the presence of an implanted blastocyst, we used scanning electron microscopy for investigation of five endometrial biopsies and three human implantation sites obtained in vitro. All specimens showed areas with endometrial pinopodes, separated by cells displaying microvilli or cilia at the apical surface. Pinopode formation was more pronounced in endometrial biopsies than in cell cultures. All blastocysts adhered to pinopode presenting cells. Endometrial surface changes were not seen around the blastocysts. The results of this study demonstrate that cultured endometrial epithelial cells are capable of pinopode formation. Furthermore, endometrial epithelial pinopodes, generally considered as a marker of endometrial receptivity, seem to be directly involved in the adhesion of the blastocyst to the endometrial surface.


Sujet(s)
Implantation embryonnaire/physiologie , Endomètre/ultrastructure , Utérus/ultrastructure , Blastocyste/cytologie , Blastocyste/ultrastructure , Cellules cultivées , Endomètre/cytologie , Femelle , Humains , Microscopie électronique à balayage , Grossesse , Utérus/cytologie
20.
Hum Reprod ; 13(1O): 2921-5, 1998 Oct.
Article de Anglais | MEDLINE | ID: mdl-9804256

RÉSUMÉ

Several retrospectively designed studies have shown an association between the presence of hydrosalpinx and impaired implantation and pregnancy rates among in-vitro fertilization (IVF) patients. In the present study we have evaluated the influence of hydrosalpinx fluid on normal human embryo development and implantation. Surplus, donated frozen embryos (n = 183) from IVF patients were used to study the effects on blastocyst development of hydrosalpinx fluid at concentrations of 50 and 100% compared with controls in S2 medium. The fluids were analysed for concentrations of electrolytes, osmolarity, protein content, endotoxin levels, bacterial or fungal contamination, pH and haemoglobin content. There was no difference in blastocyst development in cultures under mineral oil when control cultures (15/42 = 36%) were compared with cultures in 50% hydrosalpinx fluid (32/96 = 33%). The only biochemical parameter which correlated with capacity for blastocyst development was pH in hydrosalpinx fluid/medium (50/50%) after equilibration in 5% CO2 in air. When embryos were cultured in 100% hydrosalpinx fluid the blastocyst development was 14% (5/36) in comparison to control 33% (3/9). The original experiment was repeated in an open culture system without the protection of mineral oil but still in the presence of 50% hydrosalpinx fluid. The rate of blastocyst development was within the same range in the open system. In three separate experiments, the capability of expanded blastocyst to implant on multilayer artificial endometrium was tested. In these experiments, 1/3, 4/5 and 9/9 blastocysts implanted. The present study demonstrates that hydrosalpinx fluid does not generally exert any major negative effects on in-vitro development of human embryos or on the implantation process in vitro.


Sujet(s)
Implantation embryonnaire , Développement embryonnaire et foetal , Maladies des trompes de Fallope/complications , Maladies des trompes de Fallope/physiopathologie , Infertilité féminine/étiologie , Infertilité féminine/physiopathologie , Adulte , Blastocyste/cytologie , Liquides biologiques/physiologie , Milieux de culture , Femelle , Fécondation in vitro , Humains , Techniques in vitro , Infertilité féminine/thérapie , Grossesse
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