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1.
Int J Mol Sci ; 22(14)2021 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-34298913

RESUMO

Up to 11% of pregnancies extend to post-term with adverse obstetric events linked to pregnancies over 42 weeks. Oxidative stress and senescence (cells stop growing and dividing by irreversibly arresting their cell cycle and gradually ageing) can result in diminished cell function. There are no detailed studies of placental cell senescence markers across a range of gestational ages, although increased levels have been linked to pre-eclampsia before full term. This study aimed to determine placental senescence and oxidative markers across a range of gestational ages in women with uncomplicated pregnancies and those with a diagnosis of pre-eclampsia. Placentae were obtained from 37 women with uncomplicated pregnancies of 37-42 weeks and from 13 cases of pre-eclampsia of 31+2-41+2 weeks. The expression of markers of senescence, oxidative stress, and antioxidant defence (tumour suppressor protein p16INK4a, kinase inhibitor p21, interleukin-6 (IL-6), NADPH oxidase 4 (NOX4), glutathione peroxidases 1, 3, and 4 (GPx1, GPx3, and GPx4), placental growth factor (PlGF), and soluble fms-like tyrosine kinase-1 (sFlt-1)) genes was measured (quantitative real-time PCR). Protein abundance of p16INK4a, IL-6, NOX4, 8-hydroxy-2'-deoxy-guanosine (8-OHdG), and PlGF was assessed by immunocytochemistry. Placental NOX4 protein was higher in post-term than term deliveries and further increased by pre-eclampsia (p < 0.05 for all). P21 expression was higher in post-term placentae (p = 0.012) and in pre-eclampsia (p = 0.04), compared to term. Placental P16INK4a protein expression was increased post-term, compared to term (p = 0.01). In normotensive women, gestational age at delivery was negatively associated with GPx4 and PlGF (mRNA and protein) (p < 0.05 for all), whereas a positive correlation was seen with placental P21, NOX4, and P16INK4a (p < 0.05 for all) expression. Markers of placental oxidative stress and senescence appear to increase as gestational age increases, with antioxidant defences diminishing concomitantly. These observations increase our understanding of placental health and may contribute to assessment of the optimal gestational age for delivery.


Assuntos
Senescência Celular/fisiologia , Estresse Oxidativo/fisiologia , Placenta/fisiologia , Pré-Eclâmpsia/fisiopatologia , Adulto , Biomarcadores/metabolismo , Feminino , Idade Gestacional , Humanos , Placenta/metabolismo , Pré-Eclâmpsia/metabolismo , Gravidez , Resultado da Gravidez , RNA Mensageiro/metabolismo
2.
Commun Biol ; 4(1): 651, 2021 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-34140633

RESUMO

Assessment of the endometrium often necessitates a biopsy, which currently involves an invasive, transcervical procedure. Here, we present an alternative technique based on deriving organoids from menstrual flow. We demonstrate that organoids can be derived from gland fragments recovered from menstrual flow. To confirm they faithfully reflect the in vivo state we compared organoids derived from paired scratch biopsies and ensuing menstrual flow from patients undergoing in vitro fertilisation (IVF). We demonstrate that the two sets of organoids share the same transcriptome signature, derivation efficiency and proliferation rate. Furthermore, they respond similarly to sex steroids and early-pregnancy hormones, with changes in morphology, receptor expression, and production of 'uterine milk' proteins that mimic those during the late-secretory phase and early pregnancy. This technique has wide-ranging impact for non-invasive investigation and personalised approaches to treatment of common gynaecological conditions, such as endometriosis, and reproductive disorders, including failed implantation after IVF and recurrent miscarriage.


Assuntos
Endométrio/citologia , Menstruação , Organoides/citologia , Adulto , Células Cultivadas , Endométrio/crescimento & desenvolvimento , Endométrio/metabolismo , Feminino , Fertilização in vitro , Humanos , Organoides/crescimento & desenvolvimento , Organoides/metabolismo , Projetos Piloto
3.
Theriogenology ; 154: 92-99, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32535395

RESUMO

From Day 6.5-7 post-conception until its loss around Day 22, the equine embryo is enclosed in a mucinous capsule that prevents direct intercellular interaction between the trophectoderm and uterine epithelium. The embryo is, however, bathed in glycoprotein-rich secretions. In this study, lectin histochemistry was used to characterise the distribution and glycan composition of uterine glycoproteins destined for secretion, and to ascertain the local effect of an embryo on glycosylation in the endometrium. Endometrial biopsies were taken from mares in estrus, on Days 5, 8, 12 and 15 of diestrus, and on Days 12 and 15 of pregnancy and processed for lectin histochemistry. During estrus, lumenal epithelial cells were as truncated pyramids and mainly non-ciliated with glycosylated granules in the cytoplasm. Occasional ciliated cells contained few granules. Five days post-ovulation, non-ciliated cells of the lumenal epithelium were taller, and had accumulated many highly glycosylated apical granules. By Days 12 and 15 post-ovulation these cells were more cuboidal and some showed fewer secretory granules. In marked contrast, by Days 12 and 15 of pregnancy, the ciliated cells were distended, with numerous granules but non-ciliated cells had only a few in the apical cytoplasm. Glycosylation changed dramatically in pregnancy in the luminal and superficial gland epithelium, with fewer fucosylated termini, more N-acetyl galactosamine residues, together with an overall reduction in sialic acid and several other sugar structures. Glycosylation in ciliated cells on Days 12 and 15 of pregnancy showed a striking similarity to that of the blastocyst capsule. The data strongly suggests that glycoprotein production by luminal epithelial cells is influenced by the presence of a conceptus. We speculate that, as well as providing nourishment for the developing embryo, epithelial secretory glycoproteins may contribute components to the capsule, which develops only partially in embryos cultured in vitro.


Assuntos
Endométrio , Estro , Animais , Endométrio/metabolismo , Células Epiteliais , Epitélio/metabolismo , Feminino , Glicosilação , Cavalos , Gravidez
4.
Anim Reprod Sci ; 204: 66-75, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30878391

RESUMO

Placentation commences only in the right uterine horn in impala (Aepyceros melampus). To investigate possible differences in morphology or glycosylation between the two horns, right and left uterine horns from six non-pregnant, wild impala were examined morphometrically and histochemically using a panel of 23 lectins and an avidin-biotin revealing system. The presence of ovarian 3ß hydroxysteroid dehydrogenase (3ßHSD) and aromatase was also investigated using immunocytochemistry. There were few detectable differences in morphology and glycosylation between right and left uterine horns in five of the specimens, but the sixth had deep clefts and plentiful exocrine secretions in the right horn, and not the left. Heavily glycosylated clusters of supranuclear granules were present in the epithelial cells, which had many classes of O-linked glycans. The serum progestagen was not markedly different, however, from that of the other specimens. In five of the six specimens, the height of luminal epithelium was greater on the right than that on the left, and the height of the gland epithelium was also greater on the right side in four of these. The 3ßHSD and aromatase activities were present in the ovaries and were similar in impala with or without progestagen concentrations >1 ng/ml in peripheral blood. No corpus haemorrhagicum or corpus luteum could be discerned. These findings indicate there are morphological and biochemical differences between right and left uterine horns in the impala and further studies are needed on both impala and other species in which placentation commences only in one uterine horn, to establish the cyclical hormone changes which induce them.


Assuntos
Antílopes/fisiologia , Endométrio/anatomia & histologia , Animais , Endométrio/metabolismo , Feminino , Glicosilação
5.
Placenta ; 36(10): 1130-7, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26264896

RESUMO

INTRODUCTION: This study examines the glucose metabolism and glycosylation of villous macrophages (Hofbauer cells) over the course of pregnancy. MATERIALS AND METHODS: Sections of placentae from 6 weeks to term were stained with antibodies to α-amylase, glycogen synthase, glycogen phosphorylase and glucose transporters 1 and 3 (GLUT-1 and GLUT-3) while a panel of 24 lectins was applied to resin sections from 4 weeks onwards. Hofbauer cells were identified by the binding of anti-CD 163 antibody. RESULTS: Little stored glycogen could be demonstrated by Bandeiraea simplicifolia-II agglutinin binding and, by immunocytochemistry, low levels of glycogen synthase were located within the cells, though glycogen phosphorylase expression, an enzyme releasing glucose from glycogen chains, was intense. Glucose transporter-3 but not -1 was present in the cells as has been found in other types of macrophage. Lectin histochemistry showed that many classes of glycan were present in the cells, both N and O-linked, though simple fucose residues could not be demonstrated. Glycan profiles were obtained for Hofbauer cell plasma membranes, cytosol, lysosomes and small granules. With some lectins, the intensity of binding diminished after the second trimester. Morphological changes also occurred over the course of pregnancy. DISCUSSION: Hofbauer cells have properties commensurate with their phagocytic activity with numerous lysosomal vacuoles and heavily glycosylated plasma membranes and granules, most evident in the first half of pregnancy. Their carbohydrate metabolism appears to rely on glucose mobilisation rather than storage as glycogen, reflecting their peripatetic mode of existence.


Assuntos
Metabolismo dos Carboidratos , Glicogênio/metabolismo , Macrófagos/metabolismo , Placenta/imunologia , Gravidez/metabolismo , Feminino , Humanos , Placenta/ultraestrutura , Gravidez/imunologia
6.
PLoS One ; 9(1): e87621, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24498154

RESUMO

BACKGROUND: Preeclampsia (PE) is characterized by exaggerated apoptosis of the villous trophoblast of placental villi. Since p53 is a critical regulator of apoptosis we hypothesized that excessive apoptosis in PE is mediated by abnormal expression of proteins participating in the p53 pathway and that modulation of the p53 pathway alters trophoblast apoptosis in vitro. METHODS: Fresh placental villous tissue was collected from normal pregnancies and pregnancies complicated by PE; Western blotting and real-time PCR were performed on tissue lysate for protein and mRNA expression of p53 and downstream effector proteins, p21, Bax and caspases 3 and 8. To further assess the ability of p53 to modulate apoptosis within trophoblast, BeWo cells and placental villous tissue were exposed to the p53-activator, Nutlin-3, alone or in combination with the p53-inhibitor, Pifithrin-α (PFT-α). Equally, Mdm2 was knocked-down with siRNA. RESULTS: Protein expression of p53, p21 and Bax was significantly increased in pregnancies complicated by PE. Conversely, Mdm2 protein levels were significantly depleted in PE; immunohistochemistry showed these changes to be confined to trophoblast. Reduction in the negative feedback of p53 by Mdm2, using siRNA and Nutlin-3, caused an imbalance between p53 and Mdm2 that triggered apoptosis in term villous explants. In the case of Nutlin, this was attenuated by Pifithrin-α. CONCLUSIONS: These data illustrate the potential for an imbalance in p53 and Mdm2 expression to promote excessive apoptosis in villous trophoblast. The upstream regulation of p53 and Mdm2, with regard to exaggerated apoptosis and autophagy in PE, merits further investigation.


Assuntos
Pré-Eclâmpsia/genética , Pré-Eclâmpsia/metabolismo , Trofoblastos/metabolismo , Trofoblastos/patologia , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Caspase 3/genética , Caspase 3/metabolismo , Caspase 8/genética , Caspase 8/metabolismo , Vilosidades Coriônicas/metabolismo , Vilosidades Coriônicas/patologia , Feminino , Humanos , Placenta/metabolismo , Placenta/patologia , Gravidez , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas Proto-Oncogênicas c-mdm2/genética , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo
7.
Eur J Obstet Gynecol Reprod Biol ; 156(2): 177-80, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21353737

RESUMO

OBJECTIVES: To test the hypothesise that the treatment protocol used for preparation of the endometrium for frozen embryo transfer (ET) has a beneficial effect on the disorganised endometrium in women with endometriosis and leads to a higher pregnancy rate. STUDY DESIGN: We performed a retrospective, database-searched cohort study. Relevant information was collected from the electronic records of women who underwent IVF/ICSI between 1/1/2000 and 31/12/2008 in our unit. Endometriosis patients formed the study group. The rest of the women formed the control group. The two groups were subdivided, depending on whether they had fresh or frozen ET. The main outcome was live birth rate (LBR). Secondary outcomes were clinical pregnancy rate (CPR) and miscarriage rate (MR). Comparisons were performed by Chi-square and Mann-Whitney tests (SPSS 16.0). RESULTS: A total of 3763 fresh and 3523 frozen ET IVF cycles were included in our study, of which 415 (5.7%) were due to endometriosis related subfertility. In the non-endometriosis group, fresh ET had significantly higher LBR, CBR and MR than frozen ET. In women with endometriosis, down-regulated frozen ET cycles had a markedly high LBR and CPR (16.9%, 18.2%), comparable to the LBR and CPR of fresh ET cycles in the same group (19.5%, 20.2%). No significant differences were found in the LBR and CPR in fresh ET cycles between the study and the control group. In frozen ET, however, the CPR was significantly higher in the endometriosis group (18.2% versus 12.7%, P=0.048). CONCLUSION: Unlike the general IVF population, in women with endometriosis undergoing IVF, the preparation of the endometrium for frozen ET with GnRH agonists compared to fresh cycles is associated with higher LBR (16.9% versus 11.9%) and a significantly higher CPR (18.2% versus 12.7%, P=0.048). These results suggest that, in cases of endometriosis, the combined effect of GnRHa on the endometrium and the low level of ovarian steroids may simultaneously offer a better endometrial environment for implantation which may lead to better outcomes.


Assuntos
Coeficiente de Natalidade , Criopreservação , Transferência Embrionária/estatística & dados numéricos , Endometriose/epidemiologia , Adulto , Implantação do Embrião/efeitos dos fármacos , Feminino , Hormônio Liberador de Gonadotropina/agonistas , Humanos , Pessoa de Meia-Idade , Gravidez , Estudos Retrospectivos , Reino Unido/epidemiologia , Adulto Jovem
8.
J Anat ; 216(1): 144-55, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19900179

RESUMO

In the pregnant mouse endometrium, collagen fibrillogenesis is characterized by the presence of very thick collagen fibrils which are topographically located exclusively within the decidualized stroma. This dynamic biological process is in part regulated by the small leucine-rich proteoglycans decorin and biglycan. In the present study we utilized wild-type (Dcn(+/+)) and decorin-deficient (Dcn(-/-)) time-pregnant mice to investigate the evolution of non-decidualized and decidualized collagen matrix in the uterine wall of these animals. Ultrastructural and morphometric analyses revealed that the organization of collagen fibrils in the pregnant endometrium of both non-decidualized and decidualized stroma showed a great variability of shape and size, regardless of the genotype. However, the decidualized endometrium from Dcn(-/-) mice contained fibrils with larger diameter and more irregular contours as compared to the wild-type littermates. In the Dcn(-/-) animals, the proportion of thin (10-50 nm) fibrils was also higher as compared to Dcn(+/+) animals. On day 7 of pregnancy, biglycan was similarly localized in the decidualized endometrium in both genotypes. Lumican immunostaining was intense both in decidualized and non-decidualized stroma from Dcn(-/-) animals. The present results support previous findings suggesting that decorin participates in uterine collagen fibrillogenesis. In addition, we suggest that the absence of decorin disturbs the process of lateral assembly of thin fibrils, resulting in very thick collagen fibrils with irregular profiles. Our data further suggest that decorin, biglycan and lumican might play an interactive role in collagen fibrillogenesis in the mouse endometrium, a process modulated according to the stage of pregnancy.


Assuntos
Endométrio/ultraestrutura , Proteínas da Matriz Extracelular/deficiência , Colágenos Fibrilares/ultraestrutura , Proteoglicanas/deficiência , Animais , Biglicano , Proteoglicanas de Sulfatos de Condroitina/metabolismo , Proteoglicanas de Sulfatos de Condroitina/fisiologia , Decídua/ultraestrutura , Decorina , Endométrio/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Proteínas da Matriz Extracelular/fisiologia , Feminino , Sulfato de Queratano/metabolismo , Sulfato de Queratano/fisiologia , Lumicana , Camundongos , Camundongos Knockout , Microscopia Eletrônica , Gravidez , Proteoglicanas/metabolismo , Proteoglicanas/fisiologia
9.
Reprod Sci ; 16(6): 559-72, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19282503

RESUMO

Endometrial curettings from a cohort of 24 women with endometriosis were compared with matched biopsies from 14 healthy, fertile women and examined for ultrastructural changes and the secretion of glycans bound by the lectin from Dolichos biflorus. Ultrastructural analysis of glandular endometrial tissue from women with stages I to III endometriosis showed heterogeneous responses to the disease, biopsies often showing a mixture of features, combining delays in the maturation sequence with characteristics of later phenotypes particularly in the mid-late secretory phase of the menstrual cycle. Expression of glycans bound by Dolichos biflorus agglutinin was very variable in these cases but generally matched the observed ultrastructure. Biopsies from women with stage IV endometriosis showed immature gland morphology later in the cycle and also failed to express Dolichos biflorus agglutinin-binding glycans, suggesting an association between histological and biochemical function in advanced disease states. These findings may explain in part endometriosis-associated subfertility as blastocyst attachment is intimately associated with appropriate glycosylation and gland morphology.


Assuntos
Endometriose/metabolismo , Endometriose/patologia , Endométrio/metabolismo , Endométrio/ultraestrutura , Adulto , Estudos de Coortes , Endométrio/patologia , Feminino , Glicosilação , Humanos , Pessoa de Meia-Idade , Projetos Piloto , Adulto Jovem
10.
Fertil Steril ; 91(4 Suppl): 1608-10, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19131060

RESUMO

Examination of 12 paired peritoneal ectopic and eutopic endometria for histochemical binding of Dolichos biflorus agglutinin, normally found in the mid-late secretory part of the cycle, showed a failure of lectin binding in 9 of 11 secretory-phase lesions although the eutopic specimens generally stained normally. This failure of glycan expression in the secretory phase may result from various anomalies, including an inability to respond to progesterone, possibly due to a lack of, or to nonfunctional, progesterone receptors, suggesting that an ectopic environment may produce changes in tissue cell biology and hormonal responsiveness compared with that of eutopic endometrium.


Assuntos
Coristoma/patologia , Endometriose/metabolismo , Endometriose/patologia , Endométrio/patologia , Peritônio , Polissacarídeos/metabolismo , Progesterona/metabolismo , Biópsia , Coristoma/metabolismo , Endométrio/metabolismo , Feminino , Humanos , Lectinas de Plantas/metabolismo , Receptores de Progesterona/metabolismo
11.
Kidney Int ; 75(8): 824-7, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19177159

RESUMO

Drusen are a feature of age-related macular degeneration (AMD). Lesions similar in appearance to drusen are also found in the fundi of patients with membranoproliferative glomerulonephritis type II (dense deposit disease, DDD). The lamina densa of the glomerular basement membrane, in DDD, is transformed into an electron-dense structure by deposition of microscopically homogeneous material. Our study sought to compare the saccharide composition of drusen and dense deposits in the formalin-fixed, paraffin-embedded tissue from the eye and kidney. Six eye specimens were obtained from patients diagnosed with AMD but another eye was obtained from a patient with partial lipodystrophy, who died after renal failure presumably because of DDD. The kidney specimens were from three biopsy-proven cases of DDD. Glycosylation patterns were measured by the binding of 19 biotinylated lectins before and after neuraminidase pre-treatment. High mannose, bi/tri-antennary non-bisected and bisected complex N-glycan, N-acetyl glucosamine, galactose, and sialic acid residues were found in both drusen and dense deposits. Treatment with neuraminidase exposed subterminal galactose in both sites and sparse N-acetyl galactosamine residues in drusen alone. Our study found similar pathologic oligosaccharide structures in the eye and kidney, suggesting that drusen may be a common end result of retinal and glomerular disease.


Assuntos
Glomerulonefrite Membranoproliferativa/patologia , Degeneração Macular/patologia , Oligossacarídeos/química , Olho/patologia , Glicosilação , Humanos , Imuno-Histoquímica , Rim/patologia , Lectinas/metabolismo , Neuraminidase/farmacologia , Oligossacarídeos/análise
12.
Reprod Sci ; 16(1): 43-55, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19011144

RESUMO

Following a study in a baboon model of endometriosis, we here describe the morphology of ectopic peritoneal lesions in the human to examine the effects of an ectopic site on glandular structure and function. Ectopic biopsies from 17 women with endometriosis were fixed and processed for electron microscopy. Certain biopsies were also probed for intermediate filaments using immunohistochemistry. Ultrastructurally, lesions showed many different glandular morphologies with indications of delayed maturation compared to normal endometrium. Mesothelium covered some lesions and there was evidence of mesothelial invasion into the stroma. Ectopic endometriotic lesions from women with endometriosis showed ultrastructural differences from eutopic endometrium, with indications that mesothelial invasion may contribute to gland development in some lesions.


Assuntos
Endometriose/patologia , Biópsia , Epitélio/patologia , Epitélio/ultraestrutura , Feminino , Humanos , Imuno-Histoquímica , Microscopia Eletrônica , Peritônio/patologia , Peritônio/ultraestrutura
13.
J Mol Histol ; 39(1): 77-86, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17846903

RESUMO

Drusen are a marker of age-related macular degeneration (AMD). Lesions similar to drusen, both in histology and their clinical appearance, are also seen in choroidal tumours, chronic inflammatory and degenerative conditions of the eye, and in mesangiocapillary glomerulonephritis type II (MCGN-II). This study aims to compare the saccharide composition of these drusen-like lesions in the various ocular pathological groups and in MCGN-II. Formalin fixed and paraffin wax embedded tissue from 21 eyes was studied. The histological diagnoses included AMD, retinal detachment, phthisis bulbi following failed retinal detachment surgery, malignant melanoma, long-standing uveitis, glaucoma and MCGN II. Glycosylation was examined using a panel of twenty biotinylated lectins and an avidin-peroxidase DAB-cobalt revealing system, with and without neuraminidase pre-treatment. High mannose, bi/tri-nonbisected and bisected complex N-glycan, N-acetyl glucosaminyl, galactosyl and sialyl residues were found to be expressed by drusen, while treatment with neuraminidase exposed subterminal N-acetyl galactosamine and galactosyl residues. Similar binding patterns were found in the various pathological groups studied. As there was no significant difference in the lectin-binding pattern in drusen in different pathologies, a common pathogenesis or at least a final common pathway for the elaboration of carbohydrate components of drusen is suggested.


Assuntos
Glicoproteínas/metabolismo , Drusas Retinianas/metabolismo , Drusas Retinianas/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biotinilação , Oftalmopatias/metabolismo , Oftalmopatias/patologia , Humanos , Lectinas/metabolismo , Pessoa de Meia-Idade , Neuraminidase/metabolismo
14.
J Biol Chem ; 280(19): 18871-80, 2005 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-15677465

RESUMO

Latent transforming growth factor-beta-binding proteins (LTBPs) are extracellular matrix (ECM) glycoproteins that play a major role in the storage of latent TGF beta in the ECM and regulate its availability. Here we show that fibronectin is critical for the incorporation of LTBP1 and transforming growth factor-beta (TGF beta) into the ECM of osteoblasts and fibroblasts. Immunolocalization studies suggested that fibronectin provides an initial scaffold that precedes and patterns LTBP1 deposition but that LTBP1 and fibronectin are later localized in separate fibrillar networks, suggesting that the initial template is lost. Treatment of fetal rat calvarial osteoblasts with a 70-kDa N-terminal fibronectin fragment that inhibits fibronectin assembly impaired incorporation of LTBP1 and TGFbeta into the ECM. Consistent with this, LTBP1 failed to assemble in embryonic fibroblasts that lack the gene for fibronectin. LTBP1 assembly was rescued by full-length fibronectin and superfibronectin, which are capable of assembly into fibronectin fibrils, but not by other fibronectin fragments, including a 160-kDa RGD-containing fragment that activates alpha5beta1 integrins. This suggests that the critical event for LTBP1 assembly is the formation of a fibronectin fibrillar network and that integrin ligation by fibronectin molecules alone is not sufficient. Not only was fibronectin essential for the initial incorporation of LTBP1 into the ECM, but the continued presence of fibronectin was required for the continued assembly of LTBP1. These studies highlight a nonredundant role for fibronectin in LTBP1 assembly into the ECM and suggest a novel role for fibronectin in regulation of TGF beta via LTBP1 interactions.


Assuntos
Fibronectinas/química , Fibronectinas/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular/química , Fator de Crescimento Transformador beta/metabolismo , Animais , Western Blotting , Linhagem Celular Tumoral , Células Cultivadas , Ensaio de Imunoadsorção Enzimática , Matriz Extracelular/metabolismo , Fibroblastos/metabolismo , Fibronectinas/sangue , Fibronectinas/metabolismo , Humanos , Imuno-Histoquímica , Imunoprecipitação , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas de Ligação a TGF-beta Latente , Camundongos , Camundongos Transgênicos , Microscopia de Fluorescência , Microscopia Imunoeletrônica , Osteoblastos/metabolismo , Ligação Proteica , Estrutura Terciária de Proteína , Ratos , Fatores de Tempo , Transgenes
15.
Fertil Steril ; 82(5): 1379-89, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15533364

RESUMO

OBJECTIVE: To characterize endometrial development in unexplained and tubal factor infertility. DESIGN: Prospective study of 20 women with unexplained infertility, 22 with tubal factor infertility, and 21 fertile controls in the midproliferative, periovulatory, and midluteal phases of the menstrual cycle. SETTING: Reproductive Medicine Department of St. Mary's Hospital, Manchester, United Kingdom. PATIENT(S): Women awaiting assisted conception. INVESTIGATION(S): Serum hormone assays, transvaginal ultrasound, Doppler, and midluteal endometrial biopsies. MAIN OUTCOME MEASURE(S): Serum levels of E2, P, and LH, endometrial ultrasound morphometry, uterine and subendometrial artery Doppler, and endometrial histology and biochemistry. RESULT(S): Women with unexplained infertility demonstrated significantly reduced uterine artery flow velocity in all phases, significantly elevated uterine and subendometrial artery impedance in the periovulatory and midluteal phases, and significantly reduced endometrial texture in the midproliferative phase. Women with tubal factor infertility demonstrated significantly reduced uterine artery flow velocity, without a concomitant increase in impedance, and significantly greater expression of endometrial glandular and luminal keratan sulphate. CONCLUSION(S): Unexplained infertility is associated with a profound impairment of endometrial perfusion that might be amenable to treatment by perfusion enhancers. Tubal factor infertility is associated with endometrial developmental defects that might be corrected by salpingectomy. Endometrial ultrasound and Doppler studies are likely to become a vital tool in the investigation of infertility.


Assuntos
Endométrio/diagnóstico por imagem , Endométrio/metabolismo , Doenças das Tubas Uterinas/diagnóstico por imagem , Doenças das Tubas Uterinas/metabolismo , Infertilidade Feminina/diagnóstico por imagem , Infertilidade Feminina/metabolismo , Adulto , Artérias/diagnóstico por imagem , Artérias/fisiopatologia , Biópsia , Velocidade do Fluxo Sanguíneo , Endométrio/irrigação sanguínea , Endométrio/patologia , Doenças das Tubas Uterinas/complicações , Doenças das Tubas Uterinas/patologia , Feminino , Fase Folicular , Humanos , Imuno-Histoquímica , Infertilidade Feminina/etiologia , Sulfato de Queratano/metabolismo , Lectinas/metabolismo , Fase Luteal , Ovulação , Estudos Prospectivos , Ultrassonografia Doppler , Útero/irrigação sanguínea , Resistência Vascular
16.
J Histochem Cytochem ; 52(6): 749-57, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15150283

RESUMO

Explanted placental fragments may provide a more physiological in vitro model of component cell function than single cell isolates. We have characterized these fragments for cell turnover and have monitored responses from 14 normal placentas under conditions of exogenous TNFalpha and atypical oxygen concentrations (3% and 17%), conditions associated with abnormal pregnancy and an aberrant in utero environment. Explants were assessed for apoptotic morphology, immunolocalization of Mib-1 (a proliferation marker), caspase 3 activity (an apoptosis promoter), lactate dehydrogenase (a necrosis marker), and human chorionic gonadotrophin [hCG, a marker of cytotrophoblast (CT) differentiation]. Consistent with a reduction in hCG, explants under 17% O(2) (with and without TNFalpha) showed a progressive degeneration of syncytiotrophoblast (ST) (days 0-2) followed by a restoration of hCG (days 4-8) localized to newly differentiated but not syncytialized CTs. In 3% O(2), hCG showed the same initial decline but failed to recover thereafter. Proliferation dropped significantly in 17% O(2) but was restored and exaggerated sixfold in 3% O(2). All reductions in hCG were associated with cell death and caspase-3. Early apoptosis was linked with syncytial loss; later apoptosis (days 8-11) was localized to the non-ST. Prolonged exposure to TNFalpha (days 4-11) increased ST apoptosis and necrosis but 3% O(2) had no significant effect. These findings show that placental explants can accommodate many aspects of CT proliferation, differentiation, and ST apoptosis in culture. TNFalpha enhanced ST decline but 3% oxygen (compared with 17%) was associated with reduced CT differentiation and a strong shift towards proliferation. These outcomes may reflect previous morphological changes in compromised pregnancies and confirm a possible role for oxygen and TNFalpha in aberrant trophoblast turnover.


Assuntos
Oxigênio/metabolismo , Placenta/citologia , Fator de Necrose Tumoral alfa/metabolismo , Apoptose , Capilares/metabolismo , Compartimento Celular , Diferenciação Celular , Divisão Celular , Gonadotropina Coriônica/metabolismo , Vilosidades Coriônicas/metabolismo , Técnicas de Cultura , Endotélio Vascular/metabolismo , Feminino , Feto/irrigação sanguínea , Humanos , L-Lactato Desidrogenase/metabolismo , Necrose , Oxigênio/farmacologia , Placenta/metabolismo , Placenta/ultraestrutura , Gravidez , Células Estromais/metabolismo , Trofoblastos/citologia , Fator de Necrose Tumoral alfa/farmacologia
17.
Artigo em Inglês | MEDLINE | ID: mdl-15123176

RESUMO

The correlation between morphology of the mitochondria-rich cells (MR cells) in chicken lower intestine, coprodeum, and dietary sodium levels, has been investigated, using hens with differing dietary intake of NaCl and plasma aldosterone levels. Additionally, the function of the MR cells was evaluated in relation to proton secretion/exchange. Epithelium from the coprodeum was examined by optical, transmission and scanning electron microscopy, and Na(+)-transport across the coprodeal epithelium was measured electrophysiologically in Ussing-chambers. To investigate the function of MR cells, lectin-, enzyme- and immunohistochemistry methods were used. The MR cells were generally located in the epithelium on the upper parts of the sides of mucosal folds. Long microvilli, high but variable toluidine blue affinity/electrondensity and numerous mitochondria were the main features distinguishing them from the surrounding epithelial cells. Two main MR cell types were observed, differing in microvillous morphology, diameter and toluidine blue affinity/electrondensity. This probably reflected differences in maturity and activity. The MR cells expressed a positive carbonic anhydrase reaction and a proton exchange similar to the absorptive intestinal epithelial cells, but exhibited no specific demonstrable proton secretion. A close correlation between the ultrastructure of the MR-cells, dietary sodium levels, plasma aldosterone and transepithelial Na-transport was observed.


Assuntos
Galinhas/fisiologia , Mucosa Intestinal/citologia , Mucosa Intestinal/metabolismo , Intestinos/citologia , Mitocôndrias/fisiologia , Sódio/metabolismo , Animais , Anticorpos/imunologia , Anidrases Carbônicas/análise , Anidrases Carbônicas/metabolismo , Células Caliciformes/citologia , Células Caliciformes/ultraestrutura , Mucosa Intestinal/ultraestrutura , Intestinos/ultraestrutura , Transporte de Íons/fisiologia , Lectinas/análise , Lectinas/metabolismo , Microvilosidades/ultraestrutura , ATPases Translocadoras de Prótons/análise , ATPases Translocadoras de Prótons/metabolismo , Compostos de Amônio Quaternário/metabolismo , Trocador 3 de Sódio-Hidrogênio , Trocadores de Sódio-Hidrogênio/análise , Trocadores de Sódio-Hidrogênio/imunologia , Trocadores de Sódio-Hidrogênio/metabolismo
18.
Histochem J ; 34(11-12): 601-15, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-14626351

RESUMO

Genital ducts of three male Raja eglanteria were fixed and embedded in epoxy and methacrylate resin. Epoxy resin sections from the Leydig gland, upper and lower epididymis, ductus deferens and seminal vesicle were stained with 20 labelled lectins to examine their glycosylation. The Leydig gland consisted of columnar epithelial cells expressing N-linked glycans, N-acetyl galactosamine, glucosamine and lactosamine residues and sialic acid. Interspersed were ciliated cells of a different glycotype. The upper epididymis of cuboidal epithelium had a strongly glycosylated, ciliated apical surface and cytoplasmic granules that stained heavily with many lectins, with increased glycosylation compared to the Leydig gland. In the lower epididymis, tall, vacuolated cells showed some differences and a slight reduction in lectin staining. The ductus deferens contained two cell types and showed increased terminal N-acetyl galactosamine. The ciliated cuboidal epithelium of the seminal vesicle had marked differences from the ductus epithelium, with decreased N-acetyl galactosamine and lactosamine expression but increased subterminal N-acetyl lactosamine and galactosamine expression and sialylation. Spermatozoa were suspended in a glycosylated matrix and, in the seminal vesicle, were embedded in solid masses of matrix forming spermatozeugmata. These data show changes in glycan expression along the male genital tract, probably related to the nurture and maturation of the spermatozoa as they travel towards the seminal vesicle.


Assuntos
Células Epiteliais/metabolismo , Genitália Masculina/metabolismo , Rajidae/fisiologia , Espermatozoides/metabolismo , Animais , Biotina/metabolismo , Biotinilação , Epididimo/metabolismo , Epididimo/ultraestrutura , Células Epiteliais/citologia , Genitália Masculina/citologia , Glicosilação , Técnicas Imunoenzimáticas , Lectinas/metabolismo , Células Intersticiais do Testículo/metabolismo , Células Intersticiais do Testículo/ultraestrutura , Masculino , Microscopia Eletrônica , Glândulas Seminais/citologia , Glândulas Seminais/metabolismo , Espermatozoides/ultraestrutura
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