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1.
Ultrasound Obstet Gynecol ; 63(4): 446-456, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38197327

RESUMO

OBJECTIVE: To determine the diagnostic accuracy of prenatal ultrasound in detecting coarctation of the aorta (CoA). METHODS: An individual participant data meta-analysis was performed to report on the strength of association and diagnostic accuracy of different ultrasound signs in detecting CoA prenatally. MEDLINE, EMBASE and CINAHL were searched for studies published between January 2000 and November 2021. Inclusion criteria were fetuses with suspected isolated CoA, defined as ventricular and/or great vessel disproportion with right dominance on ultrasound assessment. Individual participant-level data were obtained by two leading teams. PRISMA-IPD and PRISMA-DTA guidelines were used for extracting data, and the QUADAS-2 tool was used for assessing quality and applicability. The reference standard was CoA, defined as narrowing of the aortic arch, diagnosed after birth. The most commonly evaluated parameters on ultrasound, both in B-mode and on Doppler, constituted the index test. Summary estimates of sensitivity, specificity, diagnostic odds ratio (DOR) and likelihood ratios were computed using the hierarchical summary receiver-operating-characteristics model. RESULTS: The initial search yielded 72 studies, of which 25 met the inclusion criteria. Seventeen studies (640 fetuses) were included. On random-effects logistic regression analysis, tricuspid valve/mitral valve diameter ratio > 1.4 and > 1.6, aortic isthmus/arterial duct diameter ratio < 0.7, hypoplastic aortic arch (all P < 0.001), aortic isthmus diameter Z-score of < -2 in the sagittal (P = 0.003) and three-vessel-and-trachea (P < 0.001) views, pulmonary artery/ascending aorta diameter ratio > 1.4 (P = 0.048) and bidirectional flow at the foramen ovale (P = 0.012) were independently associated with CoA. Redundant foramen ovale was inversely associated with CoA (P = 0.037). Regarding diagnostic accuracy, tricuspid valve/mitral valve diameter ratio > 1.4 had a sensitivity of 72.6% (95% CI, 48.2-88.3%), specificity of 65.4% (95% CI, 46.9-80.2%) and DOR of 5.02 (95% CI, 1.82-13.9). The sensitivity and specificity values were, respectively, 75.0% (95% CI, 61.1-86.0%) and 39.7% (95% CI, 27.0-53.4%) for pulmonary artery/ascending aorta diameter ratio > 1.4, 47.8% (95% CI, 14.6-83.0%) and 87.6% (95% CI, 27.3-99.3%) for aortic isthmus diameter Z-score of < -2 in the sagittal view and 74.1% (95% CI, 58.0-85.6%) and 62.0% (95% CI, 41.6-78.9%) for aortic isthmus diameter Z-score of < -2 in the three-vessel-and-trachea view. Hypoplastic aortic arch had a sensitivity of 70.0% (95% CI, 42.0-88.6%), specificity of 91.3% (95% CI, 78.6-96.8%) and DOR of 24.9 (95% CI, 6.18-100). The diagnostic yield of prenatal ultrasound in detecting CoA did not change significantly when considering multiple categorical parameters. Five of the 11 evaluated continuous parameters were independently associated with CoA (all P < 0.001) but all had low-to-moderate diagnostic yield. CONCLUSIONS: Several prenatal ultrasound parameters are associated with an increased risk for postnatal CoA. However, diagnostic accuracy is only moderate, even when combinations of parameters are considered. © 2024 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Coartação Aórtica , Canal Arterial , Gravidez , Feminino , Humanos , Coartação Aórtica/diagnóstico por imagem , Ultrassonografia Pré-Natal , Aorta/diagnóstico por imagem , Aorta Torácica/diagnóstico por imagem , Canal Arterial/diagnóstico por imagem , Estudos Retrospectivos
2.
Pediatr Cardiol ; 36(6): 1248-54, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25845939

RESUMO

The objective of this study was to assess the ability of different parameters to identify fetuses requiring neonatal care for coarctation of the aorta (CoA). Between January 2003 and December 2012, 175 fetuses referred for great vessel disproportion were divided into two groups: group A (n = 51) with high risk of CoA and delivery planned in tertiary care referral center and group B (n = 124) with no increased risk of CoA. In group A, diagnosis of CoA was confirmed in 38/51 (74 %). In group B, 2/124 had CoA. Multiple logistic regression analysis identified the best combination as diffusely hypoplastic and/or angular aortic arches, ventricular septal defect and aortic valve diameter <5 mm at 36-week gestational age (GA). Positive predictive value was 75 % when vessel disproportion was noted before 28-week GA and 73 % in the third trimester. Postnatal diagnosis involved 38 cases of CoA which had not been referred. One case of CoA diagnosed after birth was referred prenatally for difficulty of screening without any defect. The results of our prospective study are in agreement with those of previous series, but our false positive rate was lower especially when the diagnosis of vascular disproportion was made at third trimester. The performance of fetal cardiac screening does not seem to be very good, but prenatal diagnosis is probably not always possible: Among our three false negative cases, two had isolated vascular disproportion and the third no risk factors.


Assuntos
Coartação Aórtica/diagnóstico por imagem , Coartação Aórtica/diagnóstico , Feto/anormalidades , Idade Gestacional , Diagnóstico Pré-Natal/métodos , Ultrassonografia Pré-Natal/métodos , Aorta/anormalidades , Aorta/diagnóstico por imagem , Aorta Torácica/anormalidades , Aorta Torácica/diagnóstico por imagem , Coartação Aórtica/epidemiologia , Valva Aórtica/anormalidades , Valva Aórtica/diagnóstico por imagem , Ecocardiografia/instrumentação , Ecocardiografia/métodos , Feminino , Comunicação Interventricular/diagnóstico , Comunicação Interventricular/diagnóstico por imagem , Comunicação Interventricular/epidemiologia , Humanos , Valor Preditivo dos Testes , Gravidez , Diagnóstico Pré-Natal/instrumentação , Estudos Prospectivos , Fatores de Risco , Ultrassonografia Pré-Natal/instrumentação
3.
Pediatr Cardiol ; 33(8): 1391-6, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22639000

RESUMO

Tricuspid valve malformation is a rare congenital heart disease. Prenatal diagnosis of Ebstein's anomaly (EA) and tricuspid valve dysplasia (TVD) is associated with high mortality. There are conflicting reports concerning accurate prognostication after diagnosis in utero. The aim of our study was to assess prognostic factors based on our experience. We reviewed 37 fetuses between 1984 and June 2010 comprising 26 cases of EA and 11 cases of TVD. There were 10 terminations, 5 intrauterine deaths, 8 neonatal deaths, and 14 survivors. We found that the major prognostic factor for outcome was the flow pattern through the pulmonary valve on the first echocardiogram. Retrograde flow was strongly correlated with fetal or neonatal death (p = 8 × 10(-5)), and anterograde flow predicted good outcome (p = 8 × 10(-5)). In contrast, cardiothoracic indexes, right to left-ventricular ratio, and Celermajer index were not useful prognostic markers. The Simpson Andrews Sharland score, which was more complex, was well correlated with our series. Flow through the pulmonary valve on the first echocardiogram is a simple and excellent prognostic factor when major tricuspid valve disease is diagnosed in utero. Fetuses should be monitored throughout pregnancy, particularly those with retrograde ductus arteriosus, because several hemodynamic factors may worsen the prognosis.


Assuntos
Anomalia de Ebstein/diagnóstico por imagem , Insuficiência da Valva Tricúspide/diagnóstico por imagem , Valva Tricúspide/anormalidades , Anomalia de Ebstein/mortalidade , Ecocardiografia , Feminino , Morte Fetal , Humanos , Mortalidade Infantil , Recém-Nascido , Gravidez , Prognóstico , Estudos Retrospectivos , Insuficiência da Valva Tricúspide/mortalidade , Ultrassonografia Pré-Natal
4.
J Exp Med ; 179(1): 91-9, 1994 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-8270886

RESUMO

Recent studies have established that interleukin (IL)-10 induces growth and most notably differentiation of normal human B lymphocytes. We studied here the effects of IL-10 on the proliferation and survival of B-chronic lymphocytic leukemia (B-CLL) cells. IL-10 was found to inhibit 54-96% of the spontaneous tritiated thymidine incorporation observed in 3 of 12 B-CLL samples. Furthermore, IL-10 decreased the viable cell recovery of all five B-CLL samples tested, irrespective of whether cells were spontaneously synthesizing DNA or not. After 1 wk, B-CLL populations cultured with IL-10 were lost while those cultured without IL-10 survived. Flow cytometric analysis, DNA gel electrophoresis, and Giemsa staining all revealed that IL-10 induced B-CLL cells to die from apoptosis. This IL-10-mediated apoptosis was dose dependent and specific as it could be inhibited by a neutralizing anti-IL-10 antibody. B-CLL cells undergoing apoptosis in response to IL-10 showed decreased Bcl-2 protein levels. Addition of IL-2, IL-4, interferon gamma, and anti-CD40 monoclonal antibody prevented the IL-10-mediated apoptosis of B-CLL cells. None of the malignant B cell populations obtained from eight non-Hodgkin's lymphomas and three hairy cell leukemias underwent apoptosis after IL-10 treatment, thus suggesting that the apoptotic effect of IL-10 is specific for B-CLL cells. Thus, IL-10 inhibits the DNA synthesis and most notably the survival of B-CLL cells, findings that call for considering IL-10 in the immunotherapy of chemoresistant B-CLL.


Assuntos
Apoptose/efeitos dos fármacos , Interleucina-10/farmacologia , Leucemia de Células B/patologia , Células Cultivadas , DNA de Neoplasias/biossíntese , DNA de Neoplasias/efeitos dos fármacos , Citometria de Fluxo , Humanos , Leucemia de Células B/metabolismo , Leucemia de Células Pilosas/metabolismo , Leucemia de Células Pilosas/patologia , Linfoma não Hodgkin/metabolismo , Linfoma não Hodgkin/patologia , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2 , Células Tumorais Cultivadas
5.
J Exp Med ; 178(5): 1473-81, 1993 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-8228801

RESUMO

Interleukin 10 (IL-10) has recently been shown to induce normal human B lymphocytes to proliferate and differentiate into immunoglobulin (Ig)-secreting cells. Herein, we show that IL-10 also promotes DNA synthesis and IgM production by anti-CD40 activated B cell chronic lymphocytic leukemia (B-CLL). Most strikingly, IL-2 and IL-10 were found to synergize to induce the proliferation and differentiation of B-CLL cells. This synergy between IL-2 and IL-10 was also observed with normal B cells which proliferated strongly and secreted large amounts of IgM, IgG, and IgA. The observed synergy is likely to be due to the IL-10-induced increase of high affinity IL-2 receptors on both normal and leukemic B cells. This increase of high affinity receptor is associated to an increase of Tac/CD25 expression that can be detected by flow cytometric analysis. Taken together, these results indicate that IL-10 permits anti-CD40 activated B cells to respond to IL-2 through an induction of high affinity IL-2 receptors. This effect of IL-10 may partly explain how T cells, which activate B cells in a CD40-dependent fashion, induce B cell proliferation and differentiation mostly through IL-2.


Assuntos
Linfócitos B/imunologia , Interleucina-10/farmacologia , Interleucina-2/farmacologia , Leucemia Linfocítica Crônica de Células B/imunologia , Receptores de Interleucina-2/metabolismo , Linfócitos B/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Sinergismo Farmacológico , Humanos , Cinética , Ativação Linfocitária/efeitos dos fármacos , Tonsila Palatina , Receptores de Interleucina-2/efeitos dos fármacos , Proteínas Recombinantes/farmacologia , Regulação para Cima
6.
J Exp Med ; 175(3): 671-82, 1992 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-1371300

RESUMO

In the present report, we have investigated the in vitro differentiation of surface(s) sIgD+ and sIgD- human B cells into Ig-secreting cells in response to various stimuli. sIgD+ B cells homogeneously expressed some of the antigens identifying mantle zone B cells, but lacked expression of germinal center markers, thus confirming that the B cell populations positively selected on the basis of sIgD expression were highly enriched for naive B lymphocytes. Conversely, sIgD- B cells expressed some of the antigens specifically associated with germinal center B cells. T cell-independent differentiation of sIgD+ and sIgD- B cells could be achieved by simultaneous crosslinking of sIgs and CD40 in the presence of a mouse Ltk- cell line stably expressing human CDw32/Fc gamma RII (CDw32 L cells). In this experimental system, sIgD+ B cells were exclusively proned for IgM synthesis, whereas sIgD- B cells produced IgG, IgM, and IgA. Both the human and viral forms of interleukin 10 (IL-10) strongly increased the Ig secretion by sIgD+ and sIgD- B cells simultaneously activated through sIgs and CD40. IgM and IgG constituted the predominant Ig isotype produced by sIgD+ and sIgD- B cells, respectively, in response to IL-10. sIgD+ B cells could be induced for IgA synthesis upon co-culturing with transforming growth factor beta (TGF-beta) and IL-10, in the presence of an anti-CD40 monoclonal antibody presented by the CDw32 L cells. In contrast, TGF-beta suppressed the IL-10-mediated IgG, IgM, and IgA secretions by sIgD- B cells. sIgD+ B cells could not be induced for IgA synthesis by TGF-beta and IL-10 after crosslinking of their sIgs, suggesting that ligation of CD40 was one of the obligatory signals required for commitment of naive B cells to IgA secretion. Limiting dilution experiments indicated that the IgA-potentiating effect of TGF-beta was due to its capacity to increase the frequency of IgA-producing cells, most likely as a consequence of class switching. Taken together, our data strongly suggest that TGF-beta is involved in the regulation of IgA isotype selection in humans.


Assuntos
Células Produtoras de Anticorpos/fisiologia , Antígenos CD/imunologia , Antígenos de Diferenciação de Linfócitos B/imunologia , Linfócitos B/imunologia , Imunoglobulina A Secretora/imunologia , Interleucina-10/farmacologia , Fator de Crescimento Transformador beta/farmacologia , Antígenos CD40 , Humanos , Imunoglobulina A/biossíntese , Imunoglobulina D/análise , Imunoglobulina D/genética , Isotipos de Imunoglobulinas , Ativação Linfocitária , Fenótipo
7.
J Exp Med ; 177(6): 1815-20, 1993 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-7684436

RESUMO

We have recently demonstrated that tumor necrosis factor alpha (TNF-alpha) potentiates interleukin 3 (IL-3) and granulocyte/macrophage colony-stimulating factor-induced growth of CD34+ hematopoietic progenitor cells (HPC), and favors the generation of dendritic/Langerhans cells. The stimulatory effect of TNF-alpha was detailed in the present study. Thus, CD34+ HPC entering in cycle (S/G2M) after a 48-h pulse with IL-3 expressed the transferrin receptor (TfR), and fluorescence-activated cell sorter-separated TfR+ HPC, but not TfR-HPC, showed a high proliferative response to IL-3. In contrast, TfR-HPC were found to undergo strong proliferation in response to IL-3 + TNF-alpha. Limiting dilution experiments indicated that TNF-alpha increased both the frequency and the average size of clones generated from TfR-HPC as a result of the development of a higher number of large clones. In contrast, TNF-alpha did not enhance the IL-3-dependent proliferation of TfR+ HPC. Preculturing CD34+ HPC for 48 h with TNF-alpha enhanced the subsequent generation of IL-3-dependent colony-forming units. Precultures with TNF-alpha or cultures with suboptimal doses of TNF-alpha allowed the recruitment of cells with both granulocytic and monocytic differentiation potential. Taken together, our results indicate that TNF-alpha recruits a subpopulation of CD34+ HPC hyposensitive to IL-3, with high proliferative capacity and some features of multipotential progenitors, that are likely to be more primitive than those responding to IL-3 alone.


Assuntos
Antígenos CD/análise , Células-Tronco Hematopoéticas/efeitos dos fármacos , Interleucina-3/farmacologia , Fator de Necrose Tumoral alfa/farmacologia , Antígenos CD34 , Diferenciação Celular , Divisão Celular , Células Cultivadas , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Células-Tronco Hematopoéticas/fisiologia , Humanos , Receptores da Transferrina/análise
8.
J Exp Med ; 180(4): 1263-72, 1994 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-7523569

RESUMO

Dendritic cells, the professional antigen-presenting cells (APC) involved in T cell priming, express CD40, a molecule which triggering plays a key role in B cell growth and differentiation as well as monocyte activation. Herein we demonstrate that dendritic Langerhans cells (D-Lc) generated by culturing cord blood CD34+ progenitor cells with granulocyte/macrophage colony-stimulating and tumor necrosis factor alpha (TNF-alpha) express functional CD40 at a density higher than that found on B cells. Culturing D-Lc on CD40-ligand (CD40L) transfected L cells allowed D-Lc survival as 50 +/- 15% of seeded cells were recovered after 4 d while only 5% survived over control L cells. CD40 activation induced important morphological changes with a reduction of cytoplasmic content and a remarkable increase of dendrite development as well as an altered phenotype. In particular, CD40 triggering induced maintenance of high levels of major histocompatibility complex class II antigens and upregulation of accessory molecules such as CD58, CD80 (B7-1) and CD86 (B7-2). CD40 engagement also seems to turn on D-Lc maturation as illustrated by upregulation of CD25, a molecule usually expressed on interdigitating dendritic cells of secondary lymphoid organs. Finally, CD40 activated D-Lc secreted a limited set of cytokines (TNF-alpha, IL-8, and macrophage inflammatory protein 1 alpha [MIP-1 alpha]) whereas a similar activation induced elutriated monocytes to secrete IL-1 alpha, IL-1 beta, IL-6, IL-8, IL-10, TNF-alpha, and MIP-1 alpha. As D-Lc activated T cells upregulated CD40L, it is likely that CD40 activation of D-Lc observed herein with a fibroblast cell line stably expressing CD40L, mimics physiological interactions between dendritic cells and T cells.


Assuntos
Antígenos CD/fisiologia , Antígenos de Diferenciação de Linfócitos B/fisiologia , Células Dendríticas/fisiologia , Adulto , Antígenos CD40 , Citocinas/biossíntese , Humanos , Receptores de Interleucina-2/análise , Regulação para Cima
9.
J Exp Med ; 185(6): 1101-11, 1997 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-9091583

RESUMO

A subset of CD4+CD11c-CD3- blood cells was recently shown to develop into dendritic cells when cultured with monocyte conditioned medium. Here, we demonstrate that CD4+ CD11c-CD3- cells, isolated from tonsils, correspond to the so-called plasmacytoid T cells, an obscure cell type that has long been observed by pathologists within secondary lymphoid tissues. They express CD45RA, but not markers specific for known lymphoid- or myeloid-derived cell types. They undergo rapid apoptosis in culture, unless rescued by IL-3. Further addition of CD40-ligand results in their differentiation into dendritic cells that express low levels of myeloid antigens CD13 and CD33.


Assuntos
Antígenos CD/análise , Células Dendríticas/imunologia , Linfócitos T/imunologia , Apoptose/efeitos dos fármacos , Biomarcadores , Complexo CD3/análise , Antígenos CD4/análise , Células Cultivadas , Meios de Cultivo Condicionados , Células Dendríticas/citologia , Células Dendríticas/efeitos dos fármacos , Humanos , Integrina alfaXbeta2/análise , Interleucina-3/farmacologia , Monócitos/fisiologia , Tonsila Palatina/imunologia , Plasmócitos/citologia , Plasmócitos/imunologia , Linfócitos T/citologia , Linfócitos T/efeitos dos fármacos
10.
J Exp Med ; 183(1): 227-36, 1996 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-8551226

RESUMO

Plasma cells represent the final stage of B lymphocyte differentiation. Most plasma cells in secondary lymphoid tissues live for a few days, whereas those in the lamina propria of mucosa and in bone marrow live for several weeks. To investigate the regulation of human plasma cell survival, plasma cells were isolated from tonsils according to high CD38 and low CD20 expression. Tonsillar plasma cells express CD9, CD19, CD24, CD37, CD40, CD74, and HLA-DR, but not CD10, HLA-DQ, CD28, CD56, and Fas/CD95. Although plasma cells express intracytoplasmic Bcl-2, they undergo swift apoptosis in vitro and do not respond to CD40 triggering. Bone marrow fibroblasts and rheumatoid synoviocytes, however, prevented plasma cells from undergoing apoptosis in a contact-dependent fashion. These data indicate that fibroblasts may form a microenvironment favorable for plasma cell survival under normal and pathological conditions.


Assuntos
Apoptose , Medula Óssea/fisiologia , Fibroblastos/fisiologia , Tonsila Palatina/fisiologia , Plasmócitos/fisiologia , Antígenos CD , Artrite Reumatoide , Subpopulações de Linfócitos B , Células da Medula Óssea , Comunicação Celular , Sobrevivência Celular , Células Cultivadas , Dano ao DNA , Citometria de Fluxo , Antígenos HLA , Humanos , Imunoglobulina A/metabolismo , Imuno-Histoquímica , Mucosa , Tonsila Palatina/citologia , Tonsila Palatina/imunologia , Plasmócitos/imunologia , Plasmócitos/ultraestrutura , Proteínas Proto-Oncogênicas/isolamento & purificação , Proteínas Proto-Oncogênicas c-bcl-2 , Membrana Sinovial/citologia , Membrana Sinovial/fisiologia
11.
J Exp Med ; 185(11): 1909-18, 1997 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-9166420

RESUMO

Within T cell-rich areas of secondary lymphoid organs, interdigitating dendritic cells recruit antigen-specific T cells that then induce B cells to secrete Igs. This study investigates the possible role(s) of dendritic cells in the regulation of human B cell responses. In the absence of exogenous cytokines, in vitro generated dendritic cells (referred to as Dendritic Langerhans cells, D-Lc) induced surface IgA expression on approximately 10% of CD40-activated naive sIgD+ B cells. In the presence of IL-10 and TGF-beta, a combination of cytokines previously identified for its capacity to induce IgA switch, D-Lc strongly potentiated the induction of sIgA on CD40-activated naive B cells from 5% to 40-50%. D-Lc alone did not induce the secretion of IgA by CD40-activated naive B cells, which required further addition of IL-10. Furthermore, D-Lc skewed towards the IgA isotype at the expense of IgG, the Ig production of CD40-activated naive B cells cultured in the presence of IL-10 and TGF-beta. Importantly, under these culture conditions, both IgA1 and IgA2 were detected. In the presence of IL-10, secretion of IgA2 by CD40-activated naive B cells could be detected only in response to D-Lc and was further enhanced by TGF-beta. Collectively, these results suggest that in addition to activating T cells in the extrafollicular areas of secondary lymphoid organs, human D-Lc also directly modulate T cell-dependent B cell growth and differentiation, by inducing the IgA isotype switch.


Assuntos
Linfócitos B/imunologia , Antígenos CD40/imunologia , Células Dendríticas/imunologia , Imunoglobulina A/biossíntese , Switching de Imunoglobulina , Receptores de Antígenos de Linfócitos B/biossíntese , Antígenos CD34 , Divisão Celular , Citometria de Fluxo , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Humanos , Interleucina-10/farmacologia , Ativação Linfocitária , Reação em Cadeia da Polimerase , RNA/genética , Receptores de Antígenos de Linfócitos B/análise , Linfócitos T/imunologia , Timidina/metabolismo , Fator de Crescimento Transformador beta/farmacologia
12.
J Exp Med ; 183(5): 2075-85, 1996 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-8642318

RESUMO

The antigen receptors on T and B lymphocytes can transduce both agonist and antagonist signals leading either to activation/survival or anergy/death. The outcome of B lymphocyte antigen receptor (BCR) triggering depends upon multiple parameters which include (a) antigen concentration and valency, (b) duration of BCR occupancy, (c) receptor affinity, and (d) B cell differentiation stages. Herein, using anti-immunoglobulin kappa and lambda light chain antibodies, we analyzed the response of human naive, germinal center (GC) or memory B cells to BCR cross-linking regardless of heavy chain Ig isotype or intrinsic BCR specificity. We show that after CD40-activation, anti-BCR (kappa + gamma) can elicit an intracellular calcium flux on both GC and non-GC cells. However, prolonged BCR cross-linking induces death of CD40-activated GC B cells but enhances proliferation of naive or memory cells. Anti-kappa antibody only kills kappa + GC B cells without affecting surrounding gamma + GC B cells, thus demonstrating that BCR-mediated killing of GC B lymphocytes is a direct effect that does not involve a paracrine mechanism. BCR-mediated killing of CD40-activated GC B cells could be partially antagonized by the addition of IL-4. Moreover, in the presence of IL-4, prestimulation through CD40 could prevent subsequent anti-Ig-mediated cell death, suggesting a specific role of this combination in selection of GC B cells. This report provides evidence that in human, susceptibility to BCR killing is regulated along peripheral B cell differentiation pathway.


Assuntos
Antígenos CD/imunologia , Subpopulações de Linfócitos B/imunologia , Linfócitos B/imunologia , Receptores de Antígenos de Linfócitos B/imunologia , Anticorpos Anti-Idiotípicos , Especificidade de Anticorpos , Subpopulações de Linfócitos B/efeitos dos fármacos , Antígenos CD40/imunologia , Separação Celular , Reagentes de Ligações Cruzadas , Centro Germinativo/imunologia , Humanos , Isotipos de Imunoglobulinas , Cadeias kappa de Imunoglobulina/imunologia , Cadeias lambda de Imunoglobulina/imunologia , Memória Imunológica , Interferon gama/farmacologia , Interleucina-2/farmacologia , Interleucina-4/farmacologia , Ativação Linfocitária , Depleção Linfocítica , Proteínas Recombinantes/farmacologia
13.
Arch Pediatr ; 16(5): 409-16, 2009 May.
Artigo em Francês | MEDLINE | ID: mdl-19324538

RESUMO

UNLABELLED: Routine prenatal ultrasound screening for the detection of possible cardiopathy has existed in Upper Normandy since 1987, including the continuous training of obstetric ultrasonographers. We evaluated the profitability and the expected benefit of prenatal detection in a nonselected population in this region. METHODS: A retrospective study was undertaken from October 2003 to September 2007 in the cardiopediatric units of Upper Normandy. All fetuses and infants with a diagnosed major cardiac defect were classified into 3 groups: no possibility of anatomic surgical repair (group 1), risk of early decompensation (group 2), and anatomic surgical repair possible but without early decompensation (group 3). Prenatal and postnatal mortality and morbidity were reported. RESULTS: One hundred and sixty-five major congenital heart defects were detected prenatally and 68 postnatally. The prenatal detection rate was 71% (93, 53, and 77% for groups 1, 2, and 3, respectively; p<0.0001). The rate of pregnancy termination was 92, 17, and 45%, respectively. The mortality rate tended to be higher in the undiagnosed group of urgent neonatal heart cases (10.6% vs 4.4%). The prenatal prevalence of abnormal karyotype was 21% and was 11.5% for congenital malformation syndrome. CONCLUSION: Prenatal detection of major cardiac defects has continued to attain high success in Upper Normandy. However, 50% of urgent neonatal heart cases often remain undiagnosed, and therefore the neonatologist must treat this patient population with particular care. Prenatal diagnosis can reduce preoperative mortality and morbidity of cardiopathy with a risk of early decompensation with specific neonatal intensive care.


Assuntos
Cardiopatias Congênitas/diagnóstico , Ultrassonografia Pré-Natal , Feminino , Doenças Fetais/diagnóstico por imagem , Doenças Fetais/genética , Doenças Fetais/mortalidade , França/epidemiologia , Cardiopatias Congênitas/diagnóstico por imagem , Cardiopatias Congênitas/epidemiologia , Cardiopatias Congênitas/mortalidade , Humanos , Cariotipagem , Gravidez , Estudos Retrospectivos
14.
J Gynecol Obstet Hum Reprod ; 47(2): 35-38, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29208503

RESUMO

OBJECTIVE: To evaluate maternal tolerance to digoxin, used alone or associated to other antiarrhythmic drugs in the management of fetal tachycardia. PATIENTS AND METHODS: This retrospective study was conducted at Rouen University Hospital between January 2009 and July 2016. All women who have received a treatment by either digoxin alone or associated with another antiarrhythmic drug for fetal tachycardia were included in the study. Maternal cardiac and extracardiac adverse effects were reported and comparisons between electrocardiograms before and during treatment with digoxin alone were performed. RESULTS: Eighteen women were treated by digoxin, either alone or associated with another antiarrhythmic (sotalol, flecainide or amiodarone). During treatment, digoxin overdosing (>2ng/mL) was observed in 11 women (61%), among which 4 women had toxic levels of digoxinemia (>3ng/mL) that was symptomatic in 3 women. Cardiac complications such as sinus bradycardia, first-degree auriculo-ventricular block and Mobitz I second-degree auriculo-ventricular block were reported in four women (18.2%). Extracardiac side effects i.e. neurosensorial or digestive were diagnosed in 35.3% of women. The parameters of the electrocardiogram were not altered before and after treatment with digoxin alone. CONCLUSION: Antiarrhythmics can cause maternal cardiac complications and extracardiac side effects that can sometimes be severe but rapidly reversible upon treatment arrest.


Assuntos
Antiarrítmicos/efeitos adversos , Digoxina/efeitos adversos , Doenças Fetais/tratamento farmacológico , Complicações Cardiovasculares na Gravidez/induzido quimicamente , Complicações Cardiovasculares na Gravidez/fisiopatologia , Taquicardia/tratamento farmacológico , Adulto , Digoxina/sangue , Eletrocardiografia , Feminino , Humanos , Gravidez
15.
J Clin Invest ; 95(2): 456-63, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7532184

RESUMO

To understand the accumulation of plasma cells within RA synovium, the ability of rheumatoid synoviocytes to support the differentiation of B cells into plasma cells was explored. Tonsillar B lymphocytes cultured over confluent monolayers of synoviocytes, secreted threefold more Igs (mainly IgM) than B cells cultured directly on plastic well. More importantly, synoviocytes enhanced by 14-fold the production of Igs (mainly IgG) by B cells costimulated with Staphylococcus aureus Cowan (SAC) particles. IL-10 and, in a lower extent, IL-2 increased Ig secretion in cocultures, and their combination was synergistic. In the presence of SAC, IL-2, and IL-10, synoviocytes increased by 13-884-fold the production of IgG, which reached 0.19 ng/cell per day. RA as well as normal synoviocytes were more potent than other adherent cell lines to support terminal B cell differentiation. Synoviocyte activity involved both a support of B cell survival, and an induction of the terminal differentiation of B cells into mature plasma cells with typical morphology, high levels of intracytoplasmic Igs, and CD20- CD38high surface expression. The present observation should permit the identification of molecules involved in the maturation of B cells into plasma cells, and in their accumulation in rheumatoid synovium.


Assuntos
Artrite Reumatoide/imunologia , Linfócitos B/imunologia , Citocinas/farmacologia , Plasmócitos/imunologia , Membrana Sinovial/imunologia , Anticorpos Monoclonais , Formação de Anticorpos , Antígenos CD/análise , Antígenos CD/biossíntese , Antígenos CD20 , Antígenos de Diferenciação de Linfócitos B/biossíntese , Artrite Reumatoide/patologia , Linfócitos B/citologia , Linfócitos B/efeitos dos fármacos , Comunicação Celular/imunologia , Diferenciação Celular , Linhagem Celular , Células Cultivadas , Sinergismo Farmacológico , Citometria de Fluxo , Humanos , Técnicas Imunoenzimáticas , Imunoglobulina A/biossíntese , Imunoglobulina G/biossíntese , Imunoglobulina M/biossíntese , Interleucina-10/farmacologia , Interleucina-2/farmacologia , Cinética , Ativação Linfocitária , Plasmócitos/patologia , Proteínas Recombinantes/farmacologia , Membrana Sinovial/efeitos dos fármacos , Membrana Sinovial/patologia , Fatores de Tempo
16.
J Clin Invest ; 90(5): 1697-706, 1992 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1385474

RESUMO

In the present study, we have investigated the effects of IL-4 on the proliferation and differentiation of leukemic and normal human B cell precursors (BCP). We have demonstrated that IL-4 significantly inhibited spontaneous [3H]thymidine ([3H]-TdR) incorporation by leukemic blasts from some B lineage acute lymphoblastic leukemia (BCP-ALL) patients (8 of 14). Furthermore, IL-4 was found to suppress the spontaneous and factor-dependent (IL-7 and IL-3) proliferation of normal BCP (CD10+ surface [s] IgM- cells) isolated from fetal bone marrow. Maximum growth inhibition of either leukemic or normal BCP was reached at low IL-4 concentrations (10 U/ml), and the effect was specifically neutralized by anti-IL-4 antibody. IL-4 was further found to induce the expression of CD20 antigen on BCP-ALL cells from a number of the cases examined (5 of 8), but in contrast to leukemic cells, IL-4 failed to induce CD20 antigen on normal BCP. Finally, IL-4 was found to induce neither the expression of cytoplasmic mu chain, nor the appearance of sIgM+ cells in cultures of normal or leukemic BCP. Our data indicate that IL-4 has the potential to inhibit cell proliferation in leukemic and normal human B lymphopoiesis but is unable to drive the transition from BCP to mature B cells.


Assuntos
Linfócitos B/efeitos dos fármacos , Linfoma de Burkitt/patologia , Células-Tronco Hematopoéticas/efeitos dos fármacos , Interleucina-4/farmacologia , Antígenos CD/análise , Antígenos CD20 , Antígenos de Diferenciação de Linfócitos B/análise , Linfócitos B/imunologia , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Replicação do DNA/efeitos dos fármacos , Humanos , Imunoglobulina M/análise , Neprilisina/análise , Receptores de Antígenos de Linfócitos B/análise , Células Tumorais Cultivadas
17.
J Clin Invest ; 107(7): 835-44, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11285302

RESUMO

Three distinct dendritic cell (DC) subsets capable of stimulating allogeneic naive T cells were isolated from human thymus. The most abundant subset was represented by plasmacytoid DCs (pDCs), which secreted high amounts of IFN-alpha upon stimulation with inactivated influenza virus and thus likely correspond to the recently identified peripheral blood natural IFN-alpha/beta-producing cells (IPCs). Like those latter cells, thymic pDCs had distinctive phenotypic features (i.e., Lin(-), HLA-DR(int), IL-3R alpha(hi), CD45RA(hi), CD11c(-), CD13(-), and CD33(lo)) and developed into mature DCs upon culture in IL-3 and CD40L. Of the two other DC subsets, one displayed a phenotype of immature myeloid DCs (imDCs) (HLA-DR(int), CD11c(+), CD13(+), CD33(+)), and the other represented HLA-DR(hi) CD11c(+) mature DCs (mDCs). Since they also expressed DC-LAMP, these mDCs appear to correspond to interdigitating dendritic cells (IDCs). Thymic pDCs, but not myeloid imDCs, strongly expressed lymphoid-specific transcripts such as pre-T alpha, lambda-like, and Spi-B, thereby suggesting a possible lymphoid origin. The detection of Spi-B mRNA, not only upon in vitro maturation of pDCs, but also in freshly purified IDCs, suggests that in vivo pDCs may differentiate into IDCs.


Assuntos
Células Dendríticas/classificação , Integrina alfaXbeta2 , Timo/citologia , Adolescente , Ligante de CD40/farmacologia , Separação Celular , Criança , Pré-Escolar , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Humanos , Lactente , Interferon-alfa/farmacologia , Interleucina-3/farmacologia , Orthomyxoviridae/imunologia , RNA Mensageiro , Receptores de Interleucina-3/genética
18.
Med Mal Infect ; 36(2): 92-8, 2006 Feb.
Artigo em Francês | MEDLINE | ID: mdl-16460897

RESUMO

OBJECTIVE: The authors had for aim to describe the management of varicella and its complications in French ambulatory care. METHODS: A descriptive prospective national survey was carried out in France on patients visiting a random sample of French GPs and pediatricians (investigators) having diagnosed varicella. During an inclusion period of 4 months, the investigators enrolled all patients (adults-children) who presented with varicella or varicella related complications, and who had not previously visited the investigator for this episode. Three questionnaires were used to record the data. RESULTS: One thousand two hundred patients were enrolled by 393 physicians 75% of whom were GPs. Ninety-four percent of patients were children under 13 years of age (group I). The sex ratio (M/F) was 1.1. The mean age was 3.5 years in group I and 23.8 years in patients over 13 years of age (group II). The mean length of the varicella episode was about 10.7 days. Most patients were given a pharmaceutical prescription on inclusion, 1% were also prescribed medical procedures, 0.3% were given local treatment, and 0.09% underwent physical therapy sessions. A proportion of 12.6% of patients visited their physician twice or more for the same episode. Six group I children were hospitalized. Eighty-seven patients presented with at least one complication i.e. 7.8% (95%CI=6.3-9.3) of all episodes, mainly bacterial superinfections. CONCLUSIONS: The rate of complications associated with varicella infection was higher than usually reported in France but in the same order of magnitude as in other developed countries. Bacterial superinfections were found to be the most frequent complications of varicella.


Assuntos
Assistência Ambulatorial/normas , Varicela/terapia , Varicela/complicações , Criança , França , Inquéritos Epidemiológicos , Humanos , Pediatria/normas
19.
Diagn Interv Imaging ; 97(5): 505-12, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27012158

RESUMO

The management of patients with congenital heart disease was profoundly changed firstly by the advent of pediatric and prenatal ultrasound and then more recently by cardiac magnetic resonance imaging (MRI) and computed tomography (CT) of the heart and great vessels. The improved life expectancy of these patients has brought about new medical and imaging requirements. MRI and CT are increasing second line techniques in this group of patients. This article summarizes the advantages and limitations of CT and MRI in some frequently encountered situations in children and adults followed up for congenital heart disease.


Assuntos
Técnicas de Imagem Cardíaca/tendências , Cardiopatias Congênitas/diagnóstico por imagem , Cardiopatias Congênitas/cirurgia , Imageamento por Ressonância Magnética/tendências , Tomografia Computadorizada por Raios X/tendências , Adulto , Criança , Previsões , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Imageamento Tridimensional/tendências , Sensibilidade e Especificidade
20.
Oncogene ; 12(4): 855-62, 1996 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-8632908

RESUMO

The anti-proliferative effect of nerve growth factor (NGF) on the rat pheochromocytoma cell line PC12 has been previously shown to be accompanied by the accumulation of cells in either the G1 phase with a 2c DNA content, or with a 4c DNA content characteristic for G2/M, as evidenced by flow cytometric analysis of DNA distribution using propidium iodide. Herein, these apparently conflicting results are clarified. The present studies indicate that a simple DNA distribution profile obtained by this technique can confound interpretation of the biological effects of NGF on cell-cycle distribution due to the presence of tetraploid cells. Using cyclin D1 and incorporation of bromodeoxyuridine as markers of respectively, G1 and S phase, we show that PC12 cultures can have a considerable amount of tetraploid cells which, when in the G1 phase, have a 4c DNA content and express cyclin D1. During exposure to NGF, this population increases, reflecting the accumulation of cells in the G1 phase of the cell cycle. The data presented, support the possibility that events affecting the expression or action of G1 regulatory proteins may be involved in the molecular mechanism of the anti-mitogenic effect of NGF.


Assuntos
Ciclo Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Ciclinas/biossíntese , Fatores de Crescimento Neural/farmacologia , Proteínas Oncogênicas/biossíntese , Neoplasias das Glândulas Suprarrenais , Animais , Bromodesoxiuridina , Ciclina D1 , DNA de Neoplasias/efeitos dos fármacos , DNA de Neoplasias/metabolismo , Citometria de Fluxo , Fase G1/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Cinética , Células PC12 , Feocromocitoma , Ratos , Fase S/efeitos dos fármacos
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