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1.
BJOG ; 127(2): 159-169, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31376240

RESUMO

OBJECTIVES: To resolve the controversy regarding the presence of a microbiota in the placenta. DESIGN: Classical and molecular microbiological study. SETTING: All samples were collected during caesarean section. POPULATION: A total of 28 human placentas and six murine placentas. METHODS: All 28 human placentas were checked for 16S rRNA gene amplification products. Three locations from four selected human placentas and three 'environmental controls' for each placenta were placed in seven culture media. The four selected human placentas were further analysed using Gram stain, immunohistochemistry for bacteria, electron microscopy, and TaqMan RT-qPCR. Six placentas from three SPF mice were cut into four pieces each, and further analysed for 16S rRNA gene amplification. MAIN OUTCOME MEASURES: Microbiological and molecular evidence of bacteria. RESULTS: None of the placental cultures used for the full analysis, or their environmental cultures, was positive for bacterial growth. None of the other methods showed any evidence of bacteria. Immunohistochemistry showed negligible bacterial counts. None of the murine placentas showed evidence of 16S rRNA gene amplification. CONCLUSIONS: Our results support that the fetal environment in the womb is sterile. Based on the immunohistochemistry and the limit of detection of the other methods used, if a placental microbiome exists, it is of extreme low biomass, and thus its effect on clinical phenotypes is probably minor, if it exists at all. TWEETABLE ABSTRACT: Using several microbiological and molecular methods in parallel, we found no compelling evidence of bacteria in human and mouse placentas.


Assuntos
Líquido Amniótico/microbiologia , Microbioma Gastrointestinal/fisiologia , Microbiota/genética , Placenta/microbiologia , RNA Ribossômico 16S/fisiologia , Líquido Amniótico/imunologia , Animais , Feminino , Microbioma Gastrointestinal/imunologia , Humanos , Imuno-Histoquímica , Metagenômica , Camundongos , Placenta/imunologia , Gravidez , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
2.
Oncogene ; 36(26): 3686-3694, 2017 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-28166196

RESUMO

The tyrosine phosphatase PTPROt is a suggested tumor suppressor (TS) in B-cell chronic lymphocytic leukemia (CLL), and its expression is reduced in this disease. In order to examine how reduced PTPROt expression affects CLL in vivo we induced CLL in PTPROt-targeted mice. Unexpectedly, loss of both Ptprot alleles delayed disease detection and progression and lengthened survival relative to mice carrying two intact alleles, indicating that PTPROt fulfills a novel tumor-promoting role in CLL. Tumor cells from mice lacking PTPROt exhibited reduced B-cell receptor (BCR)-induced signaling, as well as increased apoptosis and autophagy. Inhibition of BCR/Src signaling in CLL cells induced their apoptosis, indicating that these findings are linked causally. These results suggest a cell-autonomous mechanism for the weakened CLL phenotype of PTPROt-deficient mice and uncover non-redundant roles for PTPROt in support of BCR signaling and survival of CLL cells. In contrast, loss of only one Ptprot allele induced earlier detection and progression of CLL and reduced survival, consistent with a tumor-suppressing role for PTPROt. Tumor cells from mice lacking one or both Ptprot allele exhibited increased interleukin-10 (IL-10) expression and signaling, factors known to support CLL; cells lacking one Ptprot alleles exhibited normal BCR signaling and cell death rates. We conclude that loss of one Ptprot allele promotes CLL, most likely by activating IL-10 signaling. Loss of both Ptprot alleles also reduces BCR signaling and increases cell death rates, offsetting the IL-10 effects and reducing the severity of the disease. PTPROt thus functions as an obligate haploinsufficient TS in CLL, where its expression levels determine its role as a promoter or inhibitor of the tumorigenic process in mice. Partial loss of PTPROt generates the strongest disease phenotype, suggesting that its intermediate expression levels in CLL are selected for.


Assuntos
Leucemia Linfocítica Crônica de Células B/enzimologia , Leucemia Linfocítica Crônica de Células B/genética , Proteínas Tirosina Fosfatases Classe 3 Semelhantes a Receptores/biossíntese , Proteínas Tirosina Fosfatases Classe 3 Semelhantes a Receptores/genética , Animais , Linhagem Celular Tumoral , Feminino , Haploinsuficiência , Leucemia Linfocítica Crônica de Células B/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fosforilação , Transdução de Sinais
3.
Oncogene ; 36(5): 628-638, 2017 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-27452524

RESUMO

Chronic lymphocytic leukemia (CLL) is a malignant disease of small mature lymphocytes. Signals from the CLL microenvironment promote progression of the disease and induce drug resistance. This phenomenon is largely dependent on direct contact between the malignant B cells and stromal cells. CD84 belongs to the signaling lymphocyte activation molecule family of immunoreceptors, which self-associates, forming an orthogonal homophilic dimer. We therefore hypothesized that CD84 may bridge between CLL cells and their microenvironment, promoting cell survival. Our in vitro results show that CD84 expressed on CLL cells interact with CD84 expressed on cells in their microenvironment, inducing cell survival in both sides. Blocking CD84 in vitro and in vivo disrupt the interaction of CLL cells with their microenvironment, resulting in induced cell death. Thus, our findings suggest novel therapeutic strategies based on the blockade of this CD84-dependent survival pathway.


Assuntos
Leucemia Linfocítica Crônica de Células B/metabolismo , Leucemia Linfocítica Crônica de Células B/patologia , Família de Moléculas de Sinalização da Ativação Linfocitária/biossíntese , Animais , Linhagem Celular Tumoral , Feminino , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microambiente Tumoral
4.
Hypertens Pregnancy ; 35(4): 536-541, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27391875

RESUMO

OBJECTIVE: The aim of this study was to evaluate the use of Fibroscan as a measure of liver transient elastography in women with preeclampsia and compare the results with a group of normotensive controls. MATERIALS AND METHODS: In this prospective observational case-control study, women at 24-41 weeks gestation who were diagnosed with preeclampsia using standard criteria, between January 2012 and December 2013, were included. The Fibroscan test was performed by a hepatologist 1-7 days postpartum. A control group consisted of low-risk women with normal pregnancy outcomes. RESULTS: Fibroscan results for fibrosis were significantly higher in the 32 preeclamptic women compared to the 16 normotensive women (mean 4.57 kPa vs. 3.66 kPa respectively, P = 0.01). There was no difference in liver steatosis between women with preeclampsia and normotensive women (226 vs. 225 kPa, respectively, P = 0.442) Conclusions: Fibroscan results for fibrosis were significantly higher in postpartum preeclamptic women (although within the normal range). Further studies are required in order to evaluate the usefulness of Fibroscan as an additional test in the evaluation and management of preeclampsia.


Assuntos
Técnicas de Imagem por Elasticidade , Cirrose Hepática/diagnóstico por imagem , Fígado/diagnóstico por imagem , Pré-Eclâmpsia/diagnóstico por imagem , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Cirrose Hepática/complicações , Gravidez , Adulto Jovem
5.
Clin Genet ; 89(6): 724-7, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26757254

RESUMO

Lissencephaly is a phenotypically and genetically heterogeneous group of cortical brain malformations due to abnormal neuronal migration. The identification of many causative genes has increased the understanding of normal brain development. A consanguineous family was ascertained with three siblings affected by a severe prenatal neurodevelopmental disorder characterised by fronto-parietal pachygyria, agenesis of the corpus callosum and progressive severe microcephaly. Autozygosity mapping and exome sequencing identified a homozygous novel single base pair deletion, c.1197delT in DMRTA2, predicted to result in a frameshift variant p.(Pro400Leufs*33). DMRTA2 encodes doublesex and mab-3-related transcription factor a2, a transcription factor key to the development of the dorsal telencephalon. Data from murine and zebrafish knockout models are consistent with the variant of DMTRA2 (DMRT5) as responsible for the cortical brain phenotype. Our study suggests that loss of function of DMRTA2 leads to a novel disorder of cortical development.


Assuntos
Córtex Cerebral/anormalidades , Predisposição Genética para Doença/genética , Lisencefalia/genética , Mutação , Animais , Sequência de Bases , Consanguinidade , Modelos Animais de Doenças , Exoma/genética , Saúde da Família , Feminino , Humanos , Masculino , Camundongos , Linhagem , Análise de Sequência de DNA/métodos , Irmãos , Fatores de Transcrição , Xenopus/genética , Peixe-Zebra/genética
6.
Oncogene ; 33(8): 1006-16, 2014 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-23435417

RESUMO

Chronic lymphocytic leukemia (CLL) is characterized by the accumulation of CD5+ B lymphocytes in peripheral blood, lymphoid organs and bone marrow. The main feature of the disease is accumulation of the malignant cells due to decreased apoptosis. CD84 belongs to the signaling lymphocyte activating molecule family of immunoreceptors, and has an unknown function in CLL cells. Here, we show that the expression of CD84 is significantly elevated from the early stages of the disease, and is regulated by macrophage migration inhibitory factor and its receptor, CD74. Activation of cell surface CD84 initiates a signaling cascade that enhances CLL cell survival. Both downmodulation of CD84 expression and its immune-mediated blockade induce cell death in vitro and in vivo. In addition, analysis of samples derived from an on-going clinical trial, in which human subjects were treated with humanized anti-CD74 (milatuzumab), shows a decrease in CD84 messenger RNA and protein levels in milatuzumab-treated cells. This downregulation was correlated with reduction of Bcl-2 and Mcl-1 expression. Thus, our data show that overexpression of CD84 in CLL is an important survival mechanism that appears to be an early event in the pathogenesis of the disease. These findings suggest novel therapeutic strategies based on the blockade of this CD84-dependent survival pathway.


Assuntos
Antígenos CD/fisiologia , Sobrevivência Celular , Leucemia Linfocítica Crônica de Células B/imunologia , Antígenos de Diferenciação de Linfócitos B/imunologia , Apoptose , Sequência de Bases , Estudos de Casos e Controles , Linhagem Celular Tumoral , Primers do DNA , Antígenos de Histocompatibilidade Classe II/imunologia , Humanos , Leucemia Linfocítica Crônica de Células B/patologia , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Família de Moléculas de Sinalização da Ativação Linfocitária
7.
Eur J Surg Oncol ; 39(1): 76-80, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23131429

RESUMO

AIMS: To assess the rate of parametrial involvement in a large cohort of patients who underwent radical hysterectomy for cervical cancer and to suggest an algorithm for the triage of patients to simple hysterectomy or simple trachelectomy. METHODS: Multicenter retrospective study of patients with cervical cancer stage I through IIA who underwent radical hysterectomy and pelvic lymphadenectomy. The patients were divided into 2 groups according to whether or not the parametrium was involved. The two groups were compared with regard to the clinical and histopathological variables. Logistic regression of the variables potentially assessable prior to definitive hysterectomy such as age, tumor size, lymph-vascular space invasion (LVSI) and nodal involvement was performed. RESULTS: Five hundred and thirty patients had specific histological data on parametrial involvement and in 58 (10.9%) patients, parametria was involved. Parametrial involvement was significantly associated with older age, tumors larger than 2 cm, deeper invasion, LVSI, involved surgical margins, and the presence of nodal metastasis. By triaging patients with a tumor ≤ 2 cm and no LVSI, the parametrial involvement rate was 1.8% (2/112 patients). With further triage of patients with negative nodes, the rate of parametrial involvement was 0% (0/107 patients). CONCLUSION: Using a pre-operative triage algorithm, patients with early small lesions, no LVSI and no nodal involvement may be spared radical surgical procedures and parametrectomy. Further prospective data are urgently needed.


Assuntos
Histerectomia , Excisão de Linfonodo , Pelve/cirurgia , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/cirurgia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Técnicas de Apoio para a Decisão , Feminino , Humanos , Modelos Logísticos , Metástase Linfática , Pessoa de Meia-Idade , Invasividade Neoplásica , Estadiamento de Neoplasias , Estudos Retrospectivos , Fatores de Risco , Triagem
8.
Inflamm Bowel Dis ; 16(9): 1496-504, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20222120

RESUMO

BACKGROUND: Chemokines regulate the pathways that restrict homing of specific subsets of immune cells, and thereby fine tune the immune response at specific lymphoid and peripheral tissues. CCL2 is a chemokine that induces migration of monocytes, memory T cells, and dendritic cells. Previously, we demonstrated that pM levels of CCL2 dramatically inhibit migration of T cells. The aim was to test whether subphysiological doses of CCL2 can ameliorate murine colitis and inflammation-induced colorectal cancer. METHODS: TNBS (2,4,6 trinitrobenzene sulfonic acid) colitis and dextran sodium sulfate (DSS) colitis were induced in Balb/c and C57BL/6 mice, respectively. Mice were treated daily with intraperitoneal CCL2 injections. Disease activity was assessed clinically, histologically, and by measuring inflammatory cytokine levels. In addition, an inflammatory cancer model was induced by azoxymethane-DSS (AOM-DSS) in Balb/c mice. Mice were treated daily with CCL2 for 11 weeks and then assessed for number of tumors in the colons. RESULTS: Daily administration of CCL2 (60-120 ng) significantly decreased the development of TNBS- and DSS-induced colitis. In a DSS-AOM model, CCL2-treated mice developed significantly fewer tumors (P < 0.005) at 11 weeks. Chronic inflammation in the CCL2-treated mice was significantly less pronounced as compared to phosphate-buffered saline-treated mice. CONCLUSIONS: Administration of pM levels of CCL2 significantly inhibits migration of T cells in amelioration of TNBS and DSS colitis and inhibits development of colorectal cancer in an AOM-DSS colitis model in mice. Thus, pM levels of CCL2 may be clinically beneficial as an antiinflammatory agent in IBD.


Assuntos
Quimiocina CCL2/uso terapêutico , Colite/prevenção & controle , Neoplasias Colorretais/prevenção & controle , Modelos Animais de Doenças , Doenças Inflamatórias Intestinais/prevenção & controle , Animais , Azoximetano/toxicidade , Western Blotting , Carcinógenos/toxicidade , Adesão Celular , Movimento Celular , Proliferação de Células , Colite/induzido quimicamente , Colite/metabolismo , Colo/efeitos dos fármacos , Colo/metabolismo , Colo/patologia , Neoplasias Colorretais/induzido quimicamente , Neoplasias Colorretais/metabolismo , Sulfato de Dextrana/toxicidade , Ensaio de Imunoadsorção Enzimática , Técnicas Imunoenzimáticas , Doenças Inflamatórias Intestinais/metabolismo , Doenças Inflamatórias Intestinais/patologia , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Monócitos/metabolismo , Ácido Trinitrobenzenossulfônico/toxicidade
9.
Eur J Surg Oncol ; 35(10): 1109-12, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19329270

RESUMO

AIMS: To compare the validity of four predictive models of preoperative computerized tomography (CT) scans in predicting suboptimal primary cytoreduction in patients treated for advanced ovarian cancer. PATIENTS AND METHODS: Preoperative CT scans of patients with stage III/IV epithelial ovarian cancer who underwent primary cytoreductive surgery at one of four medical centers were reviewed by radiologists blinded to surgical outcome. The validity of each set of CT criteria previously published by Nelson, Bristow, Dowdy, and Qayyum as predictors of suboptimal cytoreduction was assessed. RESULTS: Data of 123 patients were evaluated. Optimal cytoreduction (largest diameter of residual tumor < or =1cm) was obtained in 90 (73.2%) patients. All CT models were able to significantly predict surgical outcome (p<0.02). The respective sensitivity, specificity, and accuracy of the CT models to predict sub-optimal cytoreduction was 64%, 64% and 64% for Nelson's criteria, 70%, 64% and 66% for Bristow's criteria, 79%, 60%, and 65% for Dowdy's criteria, and 67% 57% and 60% for Qayyum's criteria. CONCLUSIONS: Apart from Dowdy's criteria, the accuracy rates of CT predictors of suboptimal cytoreduction in the original cohorts could not be confirmed in this cross validation. This study underscores the difficulty in devising universally applicable selection criteria or models that reliably predict surgical outcome across institutions and surgeons.


Assuntos
Técnicas de Apoio para a Decisão , Neoplasias Ovarianas/diagnóstico por imagem , Neoplasias Ovarianas/cirurgia , Seleção de Pacientes , Tomografia Computadorizada por Raios X , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias Ovarianas/patologia , Cuidados Pré-Operatórios , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Método Simples-Cego
10.
Oncogene ; 25(10): 1485-95, 2006 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-16278678

RESUMO

Heat shock proteins (Hsps) are overexpressed in many tumors, but are downregulated in some tumors. To check for a direct effect of Ha-Ras(val12) on HSP70 transcription, we transiently expressed the oncoprotein in Rat1 fibroblasts and monitored its effect on HSP70b promoter-driven reporter gene. We show that expression of Ha-Ras(val12) induced this promoter. Promoter analysis via systematic deletions and point mutations revealed that Ha-Ras(val12) induces HSP70b transcription via heat shock elements (HSEs). Also, Ha-Ras(val12) induction of HSE-mediated transcription was dramatically reduced in HSF1-/- cells. Yet, residual effect of Ha-Ras(val12) that was still measured in HSF1-/- cells suggests that some of the Ha-Ras(val12) effect is Hsf1-independent. When HSF1-/- cells, stably expressing Ha-Ras(val12), were grown on soft agar only small colonies were formed suggesting a role for heat shock factor 1 (Hsf1) in Ha-Ras(val12)-mediated transformation. Although Ha-ras(Val12) seems to be an inducer of HSP70's expression, we found that in Ha-ras(Val12-)transformed fibroblasts expression of this gene is suppressed. This suppression is correlated with higher sensitivity of Ha-ras(val12)-transformed cells to heat shock. We suggest that Ha-ras(Val12) is involved in Hsf1 activation, thereby inducing the cellular protective response. Cells that repress this response are perhaps those that acquire the capability to further proliferate and become transformed clones.


Assuntos
Proteínas de Ligação a DNA/fisiologia , Regulação da Expressão Gênica/fisiologia , Proteínas de Choque Térmico HSP70/biossíntese , Proteínas de Choque Térmico HSP70/genética , Proteína Oncogênica p21(ras)/fisiologia , Fatores de Transcrição/fisiologia , Transcrição Gênica , Transporte Ativo do Núcleo Celular , Animais , Linhagem Celular Transformada , Genes Reporter , Proteínas de Choque Térmico HSP70/antagonistas & inibidores , Células HeLa , Fatores de Transcrição de Choque Térmico , Humanos , Camundongos , Camundongos Nus , Células NIH 3T3 , Oxirredução , Fosforilação , Ratos
11.
Leukemia ; 18(12): 1948-50, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15470489

RESUMO

Grb7, a noncatalytic intracellular adaptor protein involved in cell migration, is overexpressed in certain invasive and metastatic solid tumors. We found a highly significant difference in the level of expression of Grb7 between chronic lymphocytic leukemia (CLL) cells obtained from stage I and stage IV patients (P<0.001). Using semiquantitative RT-PCR, we detected high levels of Grb7 in 88% of stage IV patients vs only 18% in stage I patients. A corresponding increase was found in the in vitro migration of stage IV CLL cells in comparison to stage I cells. The statistically significant difference in the expression of Grb7 between stage IV and stage I patients was preserved even when tested specifically in the ZAP70-positive group (P<0.01). These findings show that Grb7 levels reflect the severity of the disease, and may be used, in conjunction with ZAP70, to predict disease progression.


Assuntos
Movimento Celular , Leucemia Linfocítica Crônica de Células B/metabolismo , Proteínas/metabolismo , Estudos de Casos e Controles , Células Cultivadas , Doença , Progressão da Doença , Receptores ErbB/genética , Receptores ErbB/metabolismo , Proteína Adaptadora GRB7 , Humanos , Leucemia Linfocítica Crônica de Células B/patologia , Linfócitos/metabolismo , Linfócitos/patologia , Estadiamento de Neoplasias , Proteínas Tirosina Quinases/genética , Proteínas Tirosina Quinases/metabolismo , Proteínas/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteína-Tirosina Quinase ZAP-70
12.
J Biol Chem ; 276(50): 46701-6, 2001 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-11585817

RESUMO

In order to fully mature and participate in the humoral immune response, immature B cells must first migrate into specific areas in the spleen where they differentiate into mature cells. However, before their maturation in the spleen, immature B cells must be excluded from non-splenic secondary lymphoid organs where any antigen encounter would lead to the death of the cells because of the negative selection process. We have recently shown that immature B cells can actively exclude themselves from antigen-enriched sites by down-regulating their integrin-mediated adhesion in a process mediated by interferon-gamma (IFN-gamma). In this study, we followed the pathway by which IFN-gamma regulates the homing of B cells. We show here that the inhibitory signal of IFN-gamma is transmitted through the IFN-gamma receptor whose engagement leads to the activation of PI3K. This PI3K activation subsequently leads to the inhibition of PKCalpha phosphorylation and cytoskeleton rearrangement required for promoting integrin-mediated adhesion and migration of B cells.


Assuntos
Linfócitos B/metabolismo , Citoesqueleto/metabolismo , Regulação para Baixo , Interferon gama/biossíntese , Actinas/metabolismo , Animais , Linfócitos B/citologia , Western Blotting , Adesão Celular , Movimento Celular , Meios de Cultivo Condicionados/farmacologia , Inibidores Enzimáticos/farmacologia , Interferon gama/metabolismo , Isoenzimas/metabolismo , Camundongos , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação , Proteína Quinase C/metabolismo , Proteína Quinase C-alfa , Transdução de Sinais , Baço/citologia , Baço/metabolismo , Células Tumorais Cultivadas , Regulação para Cima
13.
J Biol Chem ; 276(29): 27203-6, 2001 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-11371575

RESUMO

Early stages of B cell development occur in the bone marrow, resulting in formation of immature B cells. From there these immature cells migrate to the spleen where they differentiate to mature cells. This final maturation step is crucial for the B cells to become responsive to antigens and to participate in the immune response. Recently, invariant chain (Ii), a major histocompatibility complex class II chaperone, as well as the transcription factors c-Rel and p65/RelA, were found to play a role in the final antigen-independent differentiation stage of B cells in the spleen. In this study, we investigated a possible link between Ii-dependent B cell maturation and the NF-kappaB pathway. Our studies indicate that Ii-induced B cell maturation involves activation of transcription mediated by the NF-kappaB p65/RelA homodimer and requires the B cell-enriched coactivator TBP-associated factor (II)105.


Assuntos
Linfócitos B/metabolismo , Proteínas de Ligação a DNA/metabolismo , NF-kappa B/metabolismo , Fatores Associados à Proteína de Ligação a TATA , Fator de Transcrição TFIID , Fatores de Transcrição/metabolismo , Animais , Sequência de Bases , Linhagem Celular , Primers do DNA , Imunofluorescência , Humanos , Camundongos
14.
Acta Obstet Gynecol Scand ; 80(2): 179-84, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11167216

RESUMO

BACKGROUND: Even though vestibular schwannomas rarely present during pregnancy, symptoms may appear or worsen particularly in this period. The clinical picture may include tinnitus, hearing abnormalities, and in large tumors, brain-stem and cerebellar compression with involvement of additional cranial nerves. Large vestibular schwannomas (also known as Acoustic Neurinomas) present a great challenge in peripartum management of both the mother and the fetus. MATERIAL AND METHOD: We present a case of a 24-year old woman, with headache, papilledema, ataxia, and multiple cranial nerve weakness, diagnosed in the 35th week of pregnancy. MRI demonstrated a huge vestibular schwannoma compressing the brainstem and causing obstructive hydrocephalus. RESULT: In the presence of high intra-cranial pressure a ventriculo-peritoneal shunt was first inserted, enabling delay of tumor surgery until after delivery. A successful elective cesarean section followed at 37 weeks, and radical tumor surgery was performed a week later. Maternal and fetal outcome were excellent. DISCUSSION: The options, sequence and timing of the neurosurgical and obstetrical interventions are discussed. Other reports of large vestibular schwannomas that presented during pregnancy are reviewed. Advances in neurosurgery, neuroradiology, neuroanesthesiology and obstetrics are highlighted, and their impact on outcome is discussed in comparison to the poor results reported in the past. Emphasis is made on the importance of early diagnosis, that necessitates high-index of suspicion by the obstetrician, in any pregnant woman presenting abnormal neurological signs. CONCLUSION: We conclude that with a cooperative team approach, maternal and fetal prognosis can today be excellent, even in cases of large vestibular schwannomas diagnosed in the late stage of pregnancy.


Assuntos
Neuroma Acústico/cirurgia , Complicações Neoplásicas na Gravidez/cirurgia , Adulto , Anestesia Obstétrica , Feminino , Humanos , Pressão Intracraniana/fisiologia , Trabalho de Parto/fisiologia , Neuroma Acústico/patologia , Gravidez , Complicações Neoplásicas na Gravidez/patologia , Derivação Ventriculoperitoneal
15.
J Exp Med ; 192(9): 1381-8, 2000 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-11067886

RESUMO

The mechanism by which immature B cells are sequestered from encountering foreign antigens present in lymph nodes or sites of inflammation, before their final maturation in the spleen, has not been elucidated. We show here that immature B cells fail to home to the lymph nodes. These cells can actively exclude themselves from antigen-enriched sites by downregulating their integrin-mediated adhesion to the extracellular matrix protein, fibronectin. This inhibition is mediated by interferon gamma secretion. Perturbation of interferon gamma activity in vivo leads to the homing of immature B cells to the lymph nodes. This is the first example of autocrine regulation of immune cell migration to sites of foreign antigen presentation.


Assuntos
Comunicação Autócrina , Linfócitos B/citologia , Linfócitos B/efeitos dos fármacos , Quimiotaxia de Leucócito/efeitos dos fármacos , Interferon gama/metabolismo , Interferon gama/farmacologia , Animais , Linfócitos B/imunologia , Linfócitos B/metabolismo , Adesão Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Meios de Cultivo Condicionados/química , Meios de Cultivo Condicionados/farmacologia , Fibronectinas/metabolismo , Citometria de Fluxo , Integrinas/metabolismo , Interleucinas/farmacologia , Linfonodos/citologia , Linfonodos/efeitos dos fármacos , Linfonodos/imunologia , Contagem de Linfócitos , Camundongos , Camundongos Endogâmicos C57BL , Baço/citologia , Baço/efeitos dos fármacos , Baço/imunologia , Acetato de Tetradecanoilforbol/farmacologia
16.
J Exp Med ; 191(6): 1057-62, 2000 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-10727467

RESUMO

The association of invariant (Ii) chain with major histocompatibility complex (MHC) class II dimers is required for proper antigen presentation to T cells by antigen-presenting cells. Mice lacking Ii chain have severe abnormalities in class II transport, T cell selection, and B cell maturation. We demonstrate here that H2-M, which is required for efficient class II antigenic peptide loading, is unexpectedly downregulated in splenocytes and mature dendritic cells (DCs) from Ii(-/-) mice. Downregulation reflects an increased rate of degradation in Ii(-/-) cells. Degradation apparently occurs within lysosomes, as it is prevented by cysteine protease inhibitors such as E64, but not by the proteasome inhibitor lactacystin. Thus, Ii chain may act as a lysosomal protease inhibitor in B cells and DCs, with its deletion contributing indirectly to the loss of H2-M.


Assuntos
Antígenos de Diferenciação de Linfócitos B/fisiologia , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Endopeptidases/metabolismo , Antígenos HLA-D/metabolismo , Antígenos de Histocompatibilidade Classe II/fisiologia , Baço/imunologia , Baço/metabolismo , Animais , Células Apresentadoras de Antígenos/imunologia , Células Apresentadoras de Antígenos/metabolismo , Antígenos de Diferenciação de Linfócitos B/biossíntese , Antígenos de Diferenciação de Linfócitos B/genética , Antígenos de Diferenciação de Linfócitos B/metabolismo , Células Cultivadas , Precipitação Química , Citosol/metabolismo , Retículo Endoplasmático/imunologia , Retículo Endoplasmático/metabolismo , Antígenos HLA-D/genética , Antígenos HLA-D/isolamento & purificação , Meia-Vida , Antígenos de Histocompatibilidade Classe II/biossíntese , Antígenos de Histocompatibilidade Classe II/genética , Antígenos de Histocompatibilidade Classe II/metabolismo , Hidrólise , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Dobramento de Proteína , RNA Mensageiro/metabolismo , Baço/citologia
17.
Obstet Gynecol ; 95(4): 482-6, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10725476

RESUMO

OBJECTIVE: To compare the efficacy of intravaginal and intrarectal plus oral indomethacin for the treatment of preterm labor. METHODS: Between December 1996 and November 1998, 46 eligible gravidas admitted with singleton pregnancies and idiopathic preterm labor before 33 gestational weeks were randomized to receive 200 mg of intravaginal or intrarectal plus oral indomethacin. RESULTS: Twenty-three subjects were allocated to each study group. The interval from initiation of treatment to delivery was significantly longer in the intravaginal indomethacin group (26.5 +/- 5.7 versus 12.6 +/- 3.7 days; P =.007). Delivery was delayed by more than 7 days in 18 of 23 subjects (78%) in the intravaginal indomethacin group compared with ten (43%) in the intrarectal plus oral indomethacin group (P =.03). Birth weights were significantly higher (2306 +/- 436 versus 1862 +/- 232 g; P =.002) and hospitalization in a neonatal intensive care unit (NICU) (3.1 +/- 0.8 versus 9.3 +/- 3. 7 days; P =.001) and mechanical ventilation (1.4 +/- 0.2 versus 5.3 +/- 1.6 days; P =.001) were significantly shorter in the intravaginal indomethacin group. CONCLUSION: Intravaginal indomethacin is more effective than intrarectal plus oral application in delaying preterm labor and is associated with higher birth weights, shorter NICU stays, and shorter intervals of mechanical ventilation.


Assuntos
Indometacina/administração & dosagem , Trabalho de Parto Prematuro/prevenção & controle , Tocolíticos/administração & dosagem , Administração Intravaginal , Administração Oral , Administração Retal , Adulto , Feminino , Humanos , Gravidez
18.
Curr Opin Obstet Gynecol ; 10(6): 447-52, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9866011

RESUMO

This review examines the preferred route of delivery in accordance with neonatal and maternal outcome of three high risk pregnancy conditions: multiple pregnancy; delivery after cesarean section; and delivery of infants with macrosomia to mothers with gestational diabetes mellitus. The most common feature of all these conditions is the lack of information, based on large prospective controlled studies, available to the treating physician for choosing the delivery route of choice and for minimizing morbidity and mortality of both infant and mother.


Assuntos
Parto Obstétrico , Resultado da Gravidez , Gravidez de Alto Risco , Prova de Trabalho de Parto , Parto Obstétrico/métodos , Diabetes Gestacional/complicações , Feminino , Macrossomia Fetal/etiologia , Humanos , Gravidez , Gravidez Múltipla , Nascimento Vaginal Após Cesárea
20.
J Biol Chem ; 271(44): 27645-51, 1996 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-8910354

RESUMO

Protein degradation is essential for quality control which retains and eliminates abnormal, unfolded, or partially assembled subunits of oligomeric proteins. The localization of this nonlysosomal pre-Golgi degradation to the endoplasmic reticulum (ER) has been mostly deduced from kinetic studies and carbohydrate analyses, while direct evidence for degradation within the ER has been provided by in vitro reconstitution of this process. In this article, we took advantage of the transport incompetence of permeabilized cells to directly demonstrate that the selective degradation of secretory IgM (sIgM) in B lymphocytes is transport-dependent. We show that, upon permeabilization of the plasma membrane with either streptolysin O or digitonin, sIgM is not degraded unless transport is allowed. Nevertheless, upon complete reduction of interchain disulfide bonds with thiols, the free mu heavy chains are degraded by a transport-independent quality control mechanism within the ER. This latter degradation is nonselective to the secretory heavy chain mus, and the membrane heavy chain mum, which is normally displayed on the surface of the B cell, is also eliminated. Moreover, the degradation of free mus is no longer restricted to B lymphocytes, and it takes place also in the ER of plasma cells which normally secrete polymers of sIgM. Conversely, when assembled with the light chain, the degradation is selective to sIgM, is restricted to B lymphocytes, and is a transport-dependent post-ER event.


Assuntos
Linfócitos B/imunologia , Imunoglobulina M/metabolismo , Animais , Linfócitos B/metabolismo , Proteínas de Bactérias , Brefeldina A , Linhagem Celular , Permeabilidade da Membrana Celular , Ciclopentanos/farmacologia , Cisteína/metabolismo , Digitonina , Ditiotreitol/farmacologia , Retículo Endoplasmático/metabolismo , Complexo de Golgi/metabolismo , Hibridomas , Cadeias Leves de Imunoglobulina/metabolismo , Imunoglobulina M/biossíntese , Cinética , Metionina/metabolismo , Camundongos , Inibidores da Síntese de Proteínas/farmacologia , Estreptolisinas , Compostos de Sulfidrila/farmacologia , Sulfonas/farmacologia
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