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1.
Intern Med J ; 41(1a): 27-34, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20492003

RESUMO

BACKGROUND/AIM: Numbers of unrelated donor allogeneic haemopoietic cell transplants (HCT) for acute myeloid leukaemia have increased in Australia in recent years. The aims of this study were to investigate the components of this change and find contributing factors to changes in outcome. METHODS: The study method was a retrospective analysis of 213 consecutive first unrelated donor HCT for acute myeloid leukaemia performed within Australia for adult patients during the years of 1992-1997 (n= 43) and 1998-2005 (n= 170). RESULTS: The proportion of patients transplanted in first or second complete remission (CR) increased markedly from 21% in 1992-1997 to 52% in 1998-2005. The cumulative incidence of relapse at 1 year post HCT was significantly lower for the later cohort (22% vs 30%, P= 0.04) and for patients transplanted in CR compared with those not in CR (16% vs 31%, P= 0.01). The overall survival probability was significantly better at 5 years post HCT for patients transplanted in 1998-2005 compared with 1992-1997 (40% vs 21%, P= 0.04). Multivariate analysis identified five independent significant favourable factors for survival among the whole patient group: age under 40 years, transplant in CR1, CR2 or first relapse, patient CMV seronegativity, good performance status and year of transplant within 1998-2005. CONCLUSION: The later cohort of patients had improved survival even after allowing for the effects of age, remission status and other factors, which suggests a general improvement in the safety of the procedure over time, particularly for patients in early disease stages at transplant.


Assuntos
Transplante de Células-Tronco Hematopoéticas/estatística & dados numéricos , Leucemia Mieloide Aguda/cirurgia , Doadores Vivos , Adolescente , Adulto , Idoso , Austrália , Causas de Morte , Comorbidade , Infecções por Citomegalovirus/epidemiologia , Feminino , Humanos , Estimativa de Kaplan-Meier , Leucemia Mieloide Aguda/epidemiologia , Masculino , Pessoa de Meia-Idade , Recidiva , Sistema de Registros , Indução de Remissão , Estudos Retrospectivos , Fatores de Risco , Transplante Homólogo , Resultado do Tratamento , Adulto Jovem
2.
Placenta ; 97: 79-88, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32792069

RESUMO

INTRODUCTION: We use an in-vitro human fetal membrane (FM) explant-based model to study inflammation-induced FM weakening, a prerequisite for PPROM. In this system, GMCSF is a critical intermediate, both necessary and sufficient for TNFα and thrombin induced FM weakening. α-Lipoic-acid (LA) blocks TNFα and thrombin, as well as GMCSF-induced weakening. Recently, we reported LA concomitantly blocks GMCSF-induction of MMPs 2, 9 and 10 and inhibition of TIMPs 1-3. The aim of this study was to show that LA blocks GMCSF-induced increases in additional proteases and reductions in additional protease inhibitors. METHODS: FM fragments were cultured±LA and then±GMCSF. In other experiments, weak versus strong, fresh FM were cultured without additions. Fragments were strength tested and media analyzed by multiplex protein ELISA for proteases and protease inhibitors. RESULTS: GMCSF induced FM weakening and concomitantly increased several Proteases (Cathepsin-S, Proteinase-3, Elastase-2) and decreased several protease inhibitors (NGAL, Cystatin-C, HE4 and Thrombospondin1). LA inhibited GMCSF-induced FM weakening and all enzymatic changes. Untreated weaker versus stronger regions of fresh FM showed comparable differences in proteases and protease inhibitor patterns to GMCSF-stimulated versus controls. CONCLUSION: LA blocks GMCSF-induced human FM weakening and associated protease increases and inhibitor decreases. The GMCSF-induced spectrum of protease/protease-inhibitor changes is similar to that in the natural weak FM fragments. In concert with previously reported GMCSF-induced changes in MMPs & TIMPs, these other protease and protease-inhibitor changes presumably facilitate FM weakening and rupture. LA blocks these GMCSF effects and therefore may be a useful agent to prevent PPROM.


Assuntos
Membranas Extraembrionárias/efeitos dos fármacos , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Peptídeo Hidrolases/metabolismo , Ácido Tióctico/farmacologia , Cistatinas/metabolismo , Membranas Extraembrionárias/metabolismo , Feminino , Humanos , Gravidez , Trombina/metabolismo , Trombospondina 1/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
3.
Placenta ; 30(4): 335-41, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19230968

RESUMO

OBJECTIVE: Human fetal membranes (FM) at term have been shown to contain a weak zone in the region overlying the cervix which exhibits characteristics of increased collagen remodeling and apoptosis. It has been hypothesized that the FM rupture initiation site is within this weak zone. Although the FM weak zone has been partially characterized, it is unclear what structural differences in the extracellular matrix result in its decreased rupture strength. A screen for differentially expressed proteins in the amnion of the weak zone versus other FM areas demonstrated that fibulin 1 was decreased. We investigated potential regional differences in all fibulin protein family members. METHODS: FM fibulins were localized by immunohistochemistry. Detected fibulins were screened by Western blot for differences in abundance in the amnion of the weak zone versus non-weak zone FM regions. Amnion epithelial and mesenchymal cells were also screened for fibulin production. RESULTS: Fibulins 1 and 5 were detected in the cytoplasm of and in a pericellular pattern surrounding all FM cells, and in a dense extracellular pattern in the amniotic compact zone. Fibulin 3 was detected within the cytoplasm of amnion epithelial and chorion trophoblast cells. Fibulins 2 and 4 were not detected. Fibulins 1, 3 and 5 demonstrated decreased abundance of 33%, 63% and 58% (all P<0.01) in amnion of the weak zone relative to other FM regions. Amnion cells produced all three detected fibulins. Furthermore, TNF inhibited amnion cell fibulin production in a dose dependent manner. CONCLUSION: Fibulins 1, 3 and 5 were localized coincident with major microfibrillar networks in amnion. Each showed decreased abundance in the amnion component of the FM weak zone. Amnion epithelial and mesenchymal cells produced all three fibulins and their abundance was inhibited by TNF. We speculate that the amnion microfibrillar layer undergoes significant remodeling with the development of the FM weak zone.


Assuntos
Proteínas de Ligação ao Cálcio/metabolismo , Membranas Extraembrionárias/metabolismo , Âmnio/citologia , Âmnio/metabolismo , Fenômenos Biomecânicos , Western Blotting , Células Cultivadas , Colo do Útero/anatomia & histologia , Colo do Útero/fisiologia , Regulação para Baixo , Proteínas da Matriz Extracelular/metabolismo , Membranas Extraembrionárias/anatomia & histologia , Membranas Extraembrionárias/fisiologia , Feminino , Humanos , Imuno-Histoquímica , Técnicas In Vitro , Gravidez , Análise Serial de Proteínas , Proteoma , Distribuição Tecidual
4.
Science ; 265(5176): 1193-201, 1994 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-7915048

RESUMO

Hypotheses about chimpanzee social behavior, phylogeography, and evolution were evaluated by noninvasive genotyping of free-ranging individuals from 20 African sites. Degrees of relatedness among individuals in one community were inferred from allele-sharing at eight nuclear simple sequence repeat (SSR) loci. Males are related on the order of half-siblings, and homozygosity is significantly increased at several SSR loci compared to Hardy-Weinberg expectations. These data support the kin-selection hypothesis for the evolution of cooperation among males. Sequence variation patterns at two mitochondrial loci indicate historically high long-distance gene flow and clarify the relationships among three allopatric subspecies. The unexpectedly large genetic distance between the western subspecies, Pan troglodytes verus, and the other two subspecies suggests a divergence time of about 1.58 million years. This result, if confirmed at nuclear loci and supported by eco-behavioral data, implies that P. t. verus should be elevated to full species rank.


Assuntos
Evolução Biológica , Variação Genética , Pan troglodytes/genética , Comportamento Social , África , Alelos , Animais , Sequência de Bases , DNA/análise , DNA/genética , Feminino , Cabelo/química , Masculino , Dados de Sequência Molecular , Pan troglodytes/classificação , Pan troglodytes/psicologia , Filogenia , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Sequências Repetitivas de Ácido Nucleico , Tanzânia
5.
Int J Lab Hematol ; 40(5): 533-539, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29806244

RESUMO

INTRODUCTION: Immunophenotyping by flow cytometry is routinely employed in distinguishing between chronic lymphocytic leukemia (CLL) and mantle cell lymphoma (MCL). Inclusion of CD200 has been reported to contribute to more reliable differentiation between CLL and MCL. We investigated the value of CD200 in assessment of atypical CLL cases. METHODS: CD200 expression on mature B cell neoplasms was studied by eight-color flow cytometry in combination with a conventional panel of flow cytometry markers. The study included 70 control samples, 63 samples with CLL or atypical CLL phenotype, 6 MCL samples, and 40 samples of other mature B cell neoplasms. RESULTS: All CLL samples were positive for CD200, whereas MCL samples were dim or negative for CD200. Of the CLL samples, 7 were atypical by conventional flow cytometry, with Matutes scores ≤3. These cases were tested for evidence of a t(11;14) translocation, characteristic of MCL, and all were negative, consistent with their classification as atypical CLL. All these atypical CLL samples were strongly positive for CD200. CONCLUSION: CD200 proved to be a useful marker for differentiation between CLL and MCL by flow cytometry. In particular, CD200 was useful in distinguishing CLL samples with atypical immunophenotypes from MCL.

6.
Placenta ; 27(11-12): 1037-51, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16516962

RESUMO

Premature rupture of the fetal membranes is a major cause of preterm birth and its associated infant morbidity and mortality. Recently, it has become clear that rupture of the fetal membranes, term or preterm, is not merely the result of the stretch and shear forces of uterine contractions, but is, in significant part, the consequence of a programmed weakening process. Work in the rat model has demonstrated that collagen remodeling, with activation of matrix metalloproteinases (MMPs), and apoptosis increase markedly in the amnion at end-gestation, suggesting that these processes are involved in fetal membrane weakening. We have developed fetal membrane strength testing equipment and a systematic tissue sampling methodology that has allowed us to demonstrate that term, non-labored, fetal membranes have a zone of weakness overlying the cervix, which contains biochemical markers of both collagen remodeling and apoptosis. These findings provide strong support for the concept of programmed fetal membrane weakening prior to labor. Our model has also been used to establish the physical properties of individual fetal membrane components (amnion, chorion), determine the sequence of events during the fetal membrane rupture process, and demonstrate that treatment of fetal membranes with TNF or IL-1beta, in vitro, induces weakness and the identical biochemical markers of collagen remodeling and apoptosis seen in the physiological weak zone. The ability to simultaneously correlate macroscopic physical properties with histological and biochemical fetal membrane characteristics, presents a unique perspective on the physiology of fetal membrane rupture.


Assuntos
Membranas Extraembrionárias/fisiologia , Ruptura Prematura de Membranas Fetais/fisiopatologia , Trabalho de Parto/fisiologia , Âmnio/fisiopatologia , Animais , Apoptose/fisiologia , Fenômenos Biofísicos , Biofísica , Córion/fisiopatologia , Citocinas/fisiologia , Decídua/fisiopatologia , Feminino , Humanos , Metaloproteinases da Matriz/metabolismo , Gravidez , Prostaglandinas/fisiologia , Resistência à Tração
7.
Cancer Res ; 40(12): 4768-74, 1980 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7438109

RESUMO

Hapten-bearing liposomes containing methotrexate and the fluorescent solute carboxyfluorescein were incubated with murine myeloma tumor cells expressing surface immunoglobulin with affinity for the hapten. Liposomes bearing the dinitrophenyl hapten became bound to MOPC 315 myeloma tumor cells, and liposomes bearing the phosphorylcholine hapten became bound in much larger amounts to TEPC 15 cells. In each case, fluorescence microscopy showed a patchy surface pattern, indicating intact liposomes at the cell surface. Few liposomes were bound to cells in the presence of excess soluble hapten or to cells lacking the relevant surface immunoglobulin. Cell-associated liposomes were quantitated by use of the fluorescence-activated cell sorter, and the pharmacological effect of the methotrexate was assessed from measurement of incorporation of radiolabeled deoxyuridine into the cells. Little inhibition of deoxyuridine incorporation was observed, because contents of the bound liposomes did not enter the cytoplasmic compartments of the cells.


Assuntos
Lipossomos/imunologia , Metotrexato/administração & dosagem , Plasmocitoma/tratamento farmacológico , Animais , DNA de Neoplasias/biossíntese , Fluoresceínas , Haptenos , Camundongos , Receptores de Antígenos de Linfócitos B/imunologia , Receptores de Antígenos de Linfócitos B/metabolismo , Tetra-Hidrofolato Desidrogenase/metabolismo
8.
Placenta ; 38: 57-66, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26907383

RESUMO

INTRODUCTION: Fetal membranes (FM) usually fail prior to delivery during term labor, but occasionally fail at preterm gestation, precipitating preterm birth. To understand the FM biomechanical properties underlying these events, study of the baseline in-vivo stretch experienced by the FM is required. This study's objective was to utilize high resolution MRI imaging to determine in-vivo FM stretch. METHODS: Eight pregnant women (38.4 ± 0.4wks) underwent abdominal-pelvic MRI prior to (2.88 ± 0.83d) caesarean delivery. Software was utilized to determine the total FM in-vivo surface area (SA) and that of its components: placental disc and reflected FM. At delivery, the SA of the disc and FM in the relaxed state were measured. In-vivo (stretched) to delivered SA ratios were calculated. FM fragments were then biaxially stretched to determine the force required to re-stretch the FM back to in-vivo SA. RESULTS: Total FM SA, in-vivo vs delivered, was 2135.51 ± 108.47 cm(2) vs 842.59 ± 35.86 cm(2); reflected FM was 1778.42 ± 107.39 cm(2) vs 545.41 ± 22.90 cm(2), and disc was 357.10 ± 28.08 cm(2) vs 297.18 ± 22.14 cm(2). The ratio (in-vivo to in-vitro SA) of reflected FM was 3.26 ± 0.11 and disc was 1.22 ± 0.10. Reflected FM re-stretched to in-vivo SA generated a tension of 72.26 N/m, corresponding to approximate pressure of 15.4 mmHg. FM rupture occurred at 295.08 ± 31.73 N/m corresponding to approximate pressure of 34 mmHg. Physiological SA was 70% of that at rupture. DISCUSSION: FM are significantly distended in-vivo. FM collagen fibers were rapidly recruited once loaded and functioned near the failure state during in-vitro testing, suggesting that, in-vivo, minimal additional (beyond physiological) stretch may facilitate rapid, catastrophic failure.


Assuntos
Membranas Extraembrionárias/fisiologia , Resistência à Tração/fisiologia , Nascimento a Termo , Fenômenos Biomecânicos , Membranas Extraembrionárias/diagnóstico por imagem , Feminino , Ruptura Prematura de Membranas Fetais/diagnóstico por imagem , Ruptura Prematura de Membranas Fetais/parasitologia , Ruptura Prematura de Membranas Fetais/fisiopatologia , Idade Gestacional , Humanos , Trabalho de Parto , Imageamento por Ressonância Magnética , Gravidez , Estresse Mecânico
9.
Endocrinology ; 116(1): 288-95, 1985 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2981067

RESUMO

cAMP modulates estrogen, hCG, and lactate syntheses by the human placenta. The major effects of cAMP are presumably mediated through the phosphorylation of specific regulatory phosphoproteins after cAMP activation of cAMP-dependent protein kinase. cAMP-dependent phosphoproteins have not been identified in the placenta. Homogenates and cytosol from term human placenta were subjected to an endogenous protein phosphorylation assay using [gamma-32P]ATP in the presence and absence of 1.0 microM cAMP. Protein phosphorylation was assessed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and autoradiography. cAMP stimulated 32P incorporation into proteins with mol wt of 25,000, 27,000, 39,000, 45,000, 52,000, 58,000, and 73,000 (P less than 0.02). Half-maximal 32P incorporation was observed with 1.0 X 10(-7) M cAMP, which was similar to the concentration required for half-maximal histone kinase activity (8.5 +/- 2.9 X 10(-8) M). cGMP induced 32P incorporation into the same placental proteins as cAMP, but 2 orders of magnitude greater cGMP concentrations were required to achieve phosphorylation levels similar to those caused by cAMP. cAMP-dependent protein kinase inhibitor completely blocked cGMP-induced phosphorylation, even when histone protein was added. Therefore, no evidence of a cGMP-dependent protein kinase or specific cGMP-dependent phosphoproteins were detected. CaCl2 (10(-8) - 10(-4) M) had no effect on cAMP-induced 32P incorporation into the seven cAMP-dependent phosphoproteins. However calcium induced 32P incorporation into four other proteins (mol wt, 97,000, 90,000, 20,000, and 19,000). Regulation of placental metabolism by catecholamines and other hormones known to mediate intracellular cAMP or calcium levels may be accomplished by phosphorylation of these phosphoproteins.


Assuntos
AMP Cíclico/farmacologia , Fosfoproteínas/metabolismo , Placenta/metabolismo , Cálcio/farmacologia , GMP Cíclico/farmacologia , Citosol/metabolismo , Feminino , Humanos , Magnésio/farmacologia , Peso Molecular , Fosforilação , Placenta/efeitos dos fármacos , Gravidez , Inibidores de Proteínas Quinases , Proteínas Quinases/metabolismo
10.
Endocrinology ; 123(4): 1771-7, 1988 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-3138102

RESUMO

It has been postulated that fetal hormonal signals act upon amnion to trigger labor via prostaglandin (PG) production. Human amnion epithelial cell cultures were established to test the effects of potential activators of the inositol phospholipid-protein kinase-C effector system on intracellular inositol phosphate turnover, intracellular free calcium ([ Ca2+]i), and PGE2 production. Oxytocin provoked 3-, 2.5-, and 4-fold increases in inositol triphosphate, inositol bisphosphate, and inositol monophosphate, respectively. [Ca2+]i, measured with the fluorescent dye fura-2, was stimulated by oxytocin and vasopressin (oxytocin greater than vasopressin) in a dose-dependent manner. The [Ca2+]i transient produced by oxytocin reached a peak in 15 sec, followed by a slow return to baseline over 10 min. Preincubation with phorbol 12-myristate-13 acetate (PMA) markedly blunted the oxytocin-induced transient. No [Ca2+]i transient was seen with leukotrienes, PG, serotonin, angiotensin, or alpha- or beta-adrenergic agents. PGE2 production increased 30- to 50-fold with phospholipase-C and PMA, and 10-fold with the calcium ionophore A23187. Oxytocin and vasopressin produced 10- and 3-fold PGE2 increases, respectively. Increased PGE2 production induced by PMA, oxytocin, and A23187 was first seen after 8 hr of incubation and reached maximal levels at 24 h. Minimal PGE2 stimulation occurred with agents that produced no [Ca2+]i transient. Direct activators of the inositol phospholipid-protein kinase-C system in human amnion induce large increases in PGE2 in human amnion cells. Oxytocin and vasopressin are hormonal activators of this system in these cells, as demonstrated by their effects on inositol phosphate turnover and [Ca2+]i. These hormones also increase PGE2 production and may influence labor by stimulating PGE2 production in amnion through the inositol phospholipid-protein kinase-C system.


Assuntos
Âmnio/metabolismo , Fosfatos de Inositol/metabolismo , Ocitocina/farmacologia , Prostaglandinas E/biossíntese , Proteína Quinase C/metabolismo , Fosfatos Açúcares/metabolismo , Âmnio/efeitos dos fármacos , Cálcio/metabolismo , Células Cultivadas , Colforsina/farmacologia , Dinoprostona , Ácido Egtázico/farmacologia , Epitélio/metabolismo , Humanos , Isoproterenol/farmacologia , Valores de Referência , Ritodrina/farmacologia , Acetato de Tetradecanoilforbol/farmacologia , Fosfolipases Tipo C/metabolismo
11.
Endocrinology ; 124(4): 2005-12, 1989 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2924732

RESUMO

Human amnion is hypothesized to be a target tissue for hormone messages from the fetus regarding labor. We have previously demonstrated prostaglandin E2 (PGE2) release in amnion after treatment with phorbol and oxytocin, but other potential agonists of the inositol phospholipid/protein kinase-C system have not been investigated. The effects of extracellular ATP on cytosolic calcium concentration [( Ca2+])i) inositol phosphate (IP) accumulation, and PGE2 production were studied in cultured human amnion cells. Intracellular free calcium [Ca2+]i was measured using the fluorescent dye fura-2. Addition of 0.01-30 microM ATP resulted in a [Ca2+]i transient which peaked within 15 sec and returned to baseline over 10 min. UTP (1 microM) was more effective than ATP (1 microM); [Ca2+]i levels rose from 233 to 2880 nM (UTP) and 2320 nM (ATP). A reduced effect was observed with other nucleotides in a rank order of agonist potency of ITP greater than CTP greater than ADP greater than GTP greater than TTP. No effect was seen with AMP, cAMP, or adenosine. This is consistent with P2 purinoceptors, as described in other tissues. ATP (100 microM) also dramatically increased IP accumulation. Inositol triphosphate, inositol bisphosphate, and inositol monophosphate were increased 7-, 9-, and 16-fold respectively. The agonist potency order of other nucleotides for IP accumulation was the same as that of [Ca2+]i. Pharmacological concentrations of ATP (1 mM) were required to increase PGE2 production. Many other nucleotides were equally effective at this concentration. ATP activates the phospholipase-C system in human amnion, as demonstrated by the increase in [Ca2+]i and inositol phosphates. The physiological significance of purinergic stimulation of this tissue remains unclear.


Assuntos
Trifosfato de Adenosina/farmacologia , Âmnio/citologia , Prostaglandinas/metabolismo , Fosfolipases Tipo C/metabolismo , Âmnio/enzimologia , Âmnio/metabolismo , Cálcio/análise , Cálcio/metabolismo , Células Cultivadas , Ativação Enzimática/efeitos dos fármacos , Epitélio/análise , Feminino , Humanos , Fosfatos de Inositol/metabolismo , Gravidez
12.
J Clin Endocrinol Metab ; 55(2): 341-6, 1982 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-6282922

RESUMO

Both beta 1- and beta 2-adrenergic receptors have been previously described in normal human placental homogenates; the cells upon whose surface membranes these receptors reside have not been identified. In order to show that a beta 1-adrenergic receptor is present on trophoblastic cells, the cells which mediate maternal-fetal transport and produce placental hormones, beta-adrenergic receptors were demonstrated in membrane fractions of human hydatidiform mole. Microscopic sections of the mole samples used demonstrated edematous villi lined by trophoblastic cells with minimal nontrophoblastic (stromal or vascular) contamination compared with placenta. (--)-[3H]Dihydroalprenolol [(--)-[3H]DHA] binding to molar membranes was reversible and saturable to a single class of sites (Kd = 0.97 +/- 0.12 nM; n = 7; maximum binding capacity, 72.9 +/- 6.4 fmol/mg protein). (--)-[3H]DHA binding was associated with catecholamine-stimulated adenylate cyclase activity. Agonist competition for the molar beta-adrenergic receptor showed the order of potency to be (--)isoproterenol much greater than norepinephrine = epinephrine, characteristic of a beta 1-adrenergic receptor subtype. Competition for (--)-[3H]DHA binding to trophoblastic membranes by the beta-adrenergic receptor subtype-specific agents metoprolol (beta 1 selective) and zinterol (beta 2 selective) was also characteristic of a homogeneous subtype of beta 1-adrenergic receptors. Because beta 1-adrenergic receptors alone were seen on trophoblast cells, the beta 2-adrenergic receptor in placenta must reside on nontrophoblastic elements (stromal or vascular endothelium). No differences in beta-adrenergic receptor binding were seen related with ploidy (2 or 3 N), the presence or absence of a fetus, or the progression of the mole to choriocarcinoma. Two choriocarcinoma cell lines, BeWo and JEG-3, however, showed no specific (--)-[3H]DHA binding. Human trophoblast contains beta 1-adrenergic receptors coupled to catecholamine-sensitive adenylate cyclase, supporting a role for catecholamines in the regulation of placental metabolism.


Assuntos
Mola Hidatiforme/análise , Receptores Adrenérgicos beta/análise , Receptores Adrenérgicos/análise , Trofoblastos/análise , Neoplasias Uterinas/análise , Adenilil Ciclases/metabolismo , Adolescente , Adulto , Di-Hidroalprenolol/metabolismo , Epinefrina/metabolismo , Feminino , Guanilil Imidodifosfato/metabolismo , Humanos , Isoproterenol/metabolismo , Norepinefrina/metabolismo , Gravidez , Receptores Adrenérgicos beta/metabolismo
13.
J Clin Endocrinol Metab ; 77(6): 1479-84, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8263130

RESUMO

Fetal membranes are postulated to play a role in paracrine signaling during the initiation of labor in women. We developed a dual chamber-fetal membrane-uterine muscle model to study the effect of human fetal membranes on spontaneous uterine contractions. In this model, full-thickness fetal membranes (amnion, chorion, and maternal decidua) are sealed into a Plexiglass chamber. The membranes partition the chamber into a maternal and fetal compartment. Chorion and decidua face the maternal side, and amnion faces the fetal side. An estrogenized rat uterine muscle strip is anchored into the maternal side as a bioassay to measure effects of fetal membranes on uterine contractions. Fetal membranes cause a 40% decrease in uterine contractions compared to basal condition (no membranes). Inhibition is reversible after removal of the membranes. The inhibition is specific to the chorion/decidual side because reversal of membranes with amnion toward the muscle did not show inhibition. Uterine contractions did not change over time in control chambers in which Parafilm substituted for membranes. A model for studying paracrine regulation of uterine contractions by human fetal membranes has been developed. The model provides evidence that fetal membranes inhibit uterine contractions. This inhibitory effect may contribute to uterine quiescence during pregnancy.


Assuntos
Membranas Extraembrionárias/fisiologia , Contração Uterina , Animais , Feminino , Humanos , Técnicas In Vitro , Gravidez , Ratos , Ratos Wistar
14.
J Clin Endocrinol Metab ; 72(5): 1073-80, 1991 May.
Artigo em Inglês | MEDLINE | ID: mdl-2022708

RESUMO

In previous work we reported that oxytocin activates phospholipase-C (PLC) and increases prostaglandin E2 (PGE2) release in amnion. Whether either of the consequences of activation of PLC by oxytocin, activation of protein kinase-C (PKC) or increases in intracellular calcium, directly results in the production of PGE2 is unknown. Phorbol esters (PMA) and epidermal growth factor (EGF) are also known to increase PGE2 release from amnion. In some tissues these agents are capable of activating the PLC postreceptor cascade system. This study was undertaken primarily to explore the mechanism of oxytocin-induced PGE2 production in amnion and secondarily to determine whether common aspects of PGE2 production by oxytocin, PMA, and EGF include activation of PLC or subsequent steps in this cascade followed by new mRNA/protein production. Involvement of PLC was assessed by inositol phosphate (IP1) turnover. IP1 turnover was increased by oxytocin (2.99 +/- 0.31-fold; P less than 0.01), but not by EGF or PMA. PMA inhibited oxytocin-provoked IP1 turnover (P less than 0.05). PKC involvement was initially evaluated with two PKC inhibitors, H7 and staurosporine. Each inhibited PGE2 production by oxytocin as well as that by PMA and EGF in a dose-dependent fashion. With H7, the IC50 for all agents was 5 microM; the IC50 for staurosporine was 2 nM for PMA and oxytocin and 5 nM for EGF. Agonist-induced PGE2 production was also assessed in cells in which PKC activity had been tachyphylaxed with a high concentration of PMA (400 ng/mL for 48 h). In such cells oxytocin and PMA no longer stimulated (P less than 0.001) PGE2 production, but EGF-stimulated PGE2 production was only slightly reduced. PKC involvement is, thus, implicated for oxytocin and PMA. Other enzymes that are inhibited by H7 and staurosporine are implicated in the production of PGE2 caused by EGF. Although tachyphylaxed cells produced no PGE2 with oxytocin, oxytocin increased intracellular calcium to levels higher than those seen in control cells (435 +/- 102 vs. 286 +/- 1.2) Actinomycin-D (P less than 0.001) and cycloheximide (P less than 0.05) inhibited PGE2 production caused by oxytocin, PMA, and EGF. PGE2 production by oxytocin in human amnion cells proceeds by activation of PKC, followed by new protein and mRNA production. Further, in cells without PKC, oxytocin-induced calcium transients do not increase PGE2. The ability of EGF to stimulate PGE2 in cells with no PKC activity also establishes that PKC activation is not a common intracellular step in the induction of PGE2 production by all agents.


Assuntos
Âmnio/metabolismo , Dinoprostona/metabolismo , Ocitocina/farmacologia , Proteína Quinase C/fisiologia , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina , Alcaloides/farmacologia , Âmnio/efeitos dos fármacos , Cálcio/metabolismo , Células Cultivadas , Cicloeximida/farmacologia , Dactinomicina/farmacologia , Ativação Enzimática/efeitos dos fármacos , Ativação Enzimática/fisiologia , Fator de Crescimento Epidérmico/metabolismo , Feminino , Humanos , Isoquinolinas/farmacologia , Ésteres de Forbol/metabolismo , Piperazinas/farmacologia , Gravidez , Proteína Quinase C/genética , Proteína Quinase C/metabolismo , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Estaurosporina , Fatores de Tempo , Fosfolipases Tipo C/genética , Fosfolipases Tipo C/metabolismo , Fosfolipases Tipo C/fisiologia
15.
J Clin Endocrinol Metab ; 56(5): 1035-41, 1983 May.
Artigo em Inglês | MEDLINE | ID: mdl-6300172

RESUMO

cAMP modulates estrogen, hCG, and lactate syntheses by human placenta, cAMP presumably exerts its major intracellular effect by binding to cAMP-dependent protein kinase (cAMP-PK), which, in turn, phosphorylates regulatory proteins within the target cell. cAMP binding and cAMP-PK have not been previously identified in placenta. [3H]cAMP binding to crude cytosol fractions of term placenta was rapid, saturable, and reversible. Scatchard analyses of saturation experiments of [3H]cAMP binding to placental cytosol were linear (Kd = 1.13 +/- 0.11 x 10(-8) M; n = 5). The binding capacity was 1.27 +/- 0.18 pmol/mg protein. Competition for the [3H]cAMP-binding site followed the potency order cAMP much greater than cGMP much greater than (Bu)2cAMP, analogous to cAMP binding to cAMP-PK in other tissues. ADP, ATP, and adenosine did not compete for the [3H]cAMP-binding site. cAMP significantly enhanced phosphorylation of histone protein by placental cytosol (activity ratio, 0.57 +/- 0.04; P less than 0.01). Two peaks of [3H]cAMP binding and coincident cAMP-PK activity were identified by DEAE-cellulose column chromatography of placental cytosol corresponding to classical type I and type II cAMP-PK. While the majority of the cAMP-PK was found in placental cytosol, cAMP-PK was also demonstrated in crude microsomal and microvillous brush border membranes of human placenta after solubilization with Triton X-100 (P less than 0.05). Regulation of placental function by catecholamines and other hormones known to mediate cAMP levels may be accomplished through the phosphorylation of cellular proteins by cAMP-dependent protein kinases.


Assuntos
Proteínas de Transporte/metabolismo , Proteína Receptora de AMP Cíclico , AMP Cíclico/farmacologia , Placenta/enzimologia , Proteínas Quinases/metabolismo , Ligação Competitiva , Cromatografia DEAE-Celulose , AMP Cíclico/metabolismo , Citosol/enzimologia , Feminino , Histonas/metabolismo , Humanos , Microssomos/enzimologia , Microvilosidades/enzimologia , Fosforilação , Gravidez
16.
Best Pract Res Clin Haematol ; 17(2): 263-76, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15302339

RESUMO

Haematopoietic stem cell transplantation (HSCT) is now being investigated as a potential therapy for patients with severe refractory rheumatoid arthritis unresponsive to conventional therapies, including tumour necrosis factor-alpha blockade. Pilot studies and an analysis of worldwide cases included in the European Group for Blood and Marrow Transplantation/Autologous Blood and Marrow Transplant Registry registry have enabled the progression of the technique. HSCT is well tolerated in patients with rheumatoid arthritis, and there has been no transplant-related mortality. Although HSCT is not a cure, an improved response to previously ineffective therapies is often seen. Further research is, however, required, and this procedure is still considered appropriate only for those patients for whom there is no reasonable therapeutic alternative. This paper reviews all the previous data relating to HSCT in rheumatoid arthritis, outlines the current stand and discusses future protocol options and research.


Assuntos
Artrite Reumatoide/terapia , Transplante de Células-Tronco , Células-Tronco Hematopoéticas/patologia , Humanos , Transplante Autólogo , Resultado do Tratamento
17.
Pediatrics ; 106(2 Pt 1): 306-10, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10920156

RESUMO

BACKGROUND: Normative data for hematologic values in the very low birth weight infants are limited and inconsistent, with the reported mean hematocrit (HCT) in these infants ranging from 43.5% to 60%. No data are available on the effect of race. OBJECTIVES: To establish normative data for hemoglobin (Hb) and HCT by arterial sampling obtained during the first 3 hours after birth in black and white premature infants

Assuntos
População Negra , Índices de Eritrócitos , Idade Gestacional , Hematócrito , Hemoglobinometria , Recém-Nascido de muito Baixo Peso/sangue , População Branca , Feminino , Humanos , Recém-Nascido , Masculino , Ohio , Valores de Referência , Estudos Retrospectivos
18.
Proc Biol Sci ; 249(1326): 293-7, 1992 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-1359560

RESUMO

We describe a non-invasive method of determining the subspecies identity of common chimpanzees (Pan troglodytes), based on subspecies-specific sequence differences in the mitochondrial genome. This procedure involves the extraction of DNA from hair, the amplification of a short (410 base pair (b.p.)) segment of the non-coding displacement loop (D-loop) by the polymerase chain reaction (PCR), and subspecies identification based on rapid allele-specific oligonucleotide (ASO) probe dot-blot typing. This approach will contribute to: (i) the colony-level management of captive chimpanzees by enabling managers to recognize hybrids between subspecies and minimize outbreeding depression; (ii) the recognition of inappropriately matched individuals in comparative behavioural and experimental studies; and (iii) forensic questions surrounding the origin of illegally traded animals.


Assuntos
DNA/genética , Pan troglodytes/classificação , Pan troglodytes/genética , Alelos , Animais , Sequência de Bases , Variação Genética , Cabelo/química , Dados de Sequência Molecular , Sondas de Oligonucleotídeos , Homologia de Sequência do Ácido Nucleico , Especificidade da Espécie
19.
Placenta ; 13(3): 241-53, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1321977

RESUMO

We studied the beta-adrenergic system in the human decidua and its effect on prostaglandin E2 and F2a release from dispersed decidual cells in culture. Beta-adrenergic receptors in decidual membranes were partially characterized using (+)[125I]HYP. Specific binding was demonstrated with maximum binding capacity (Bmax) of 70 +/- 10.6 fmol/mg and an affinity (KD) of 20.85 +/- 1.86 pmol. cAMP dependent phosphoproteins in decidual cytosol were also identified. Two phosphoproteins of M(r) 42,000 and 22,000 were seen in all preparations. Three others (M(r) 39,000, 23,000 and 21,000) were identified in only some of the preparations. Phosphoproteins of similar M(r) to those seen in cytosol prepared from decidual homogenates were also identified in cytosol of cultured decidual cells. Phosphorylation of the 42,000 M(r) and 22,000 M(r) proteins was maximal (3.04 +/- 0.35-fold and 5.7 +/- 0.68-fold) with 10(-6) M cAMP. Cultured decidual cells produced prostaglandin E2 and F2a which increased in a dose-dependent manner in response to dbcAMP, forskolin or isoproterenol. The decidua contains an intact beta-adrenergic system that, when activated, is capable of phosphorylating specific proteins and modulating prostaglandin release.


Assuntos
Adenilil Ciclases/metabolismo , Decídua/metabolismo , Prostaglandinas/biossíntese , Bucladesina/farmacologia , Células Cultivadas , Colforsina/farmacologia , AMP Cíclico/metabolismo , Decídua/efeitos dos fármacos , Dinoprosta/biossíntese , Dinoprostona/biossíntese , Feminino , Humanos , Isoproterenol/farmacologia , Peso Molecular , Fosfoproteínas/isolamento & purificação , Fosfoproteínas/metabolismo , Fosforilação , Gravidez , Receptores Adrenérgicos beta/efeitos dos fármacos , Receptores Adrenérgicos beta/metabolismo
20.
Placenta ; 24(2-3): 173-80, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12566244

RESUMO

Foetal membrane rupture is thought to follow from gene-controlled tissue remodelling and apoptosis. We reported previously that staurosporine, cycloheximide, actinomycin D, as well as more physiological apoptotic agents (lactosylceramide, 15d-PGJ(2)) increase prostaglandin release in parallel with induction of apoptosis in WISH and amnion epithelial cells. Also, inhibition of prostaglandin release by cyclooxygenase inhibitors or PKA activators is accompanied by a parallel decrease in apoptosis. We hypothesize that amnion prostaglandin metabolism is linked with apoptosis in amnion epithelial cells and thus to membrane rupture. Amnion mesenchymal cells are also critical for membrane integrity. Their susceptibility to apoptotic agents is unknown and is the subject of this report. In amnion epithelial cells, lactosylceramide (125 microM) induced 6.5-fold, 20-fold increases in PGE(2) and NMP production (apoptosis), respectively. Conversely, in mesenchymal cells, lactosylceramide doses up to 200 microM had no effect on PGE(2) or NMP release. In both cell types, incubation with 15d-PGJ(2) (5-100 microM) demonstrated dose and time dependent increases in PGE(2) and NMP. PKA activators inhibited 15d-PGJ(2) induced PGE(2) release and apoptotis in epithelial cells, but not in mesenchymal cells, however. Major amnion cell types have different sensitivities to physiological apoptotic agents. Prostaglandin release occurs coincident with apoptosis in both amnion epithelial and mesenchymal cells.


Assuntos
Âmnio/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Fatores Imunológicos/farmacologia , Lactosilceramidas/farmacologia , Prostaglandina D2/farmacologia , 8-Bromo Monofosfato de Adenosina Cíclica/farmacologia , Adulto , Âmnio/metabolismo , Âmnio/patologia , Linhagem Celular , Inibidores de Ciclo-Oxigenase/farmacologia , Fragmentação do DNA/efeitos dos fármacos , Dinoprostona/metabolismo , Relação Dose-Resposta a Droga , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Feminino , Humanos , Mesoderma/efeitos dos fármacos , Mesoderma/metabolismo , Mesoderma/patologia , Nitrobenzenos/farmacologia , Gravidez , Prostaglandina D2/análogos & derivados , Pirazóis/farmacologia , Sulfonamidas/farmacologia
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