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1.
Kathmandu Univ Med J (KUMJ) ; 14(53): 87-89, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27892449

RESUMO

Hysteroscopic surgery is indicated for the treatment of several intrauterine diseases. The surgeon needs to be aware of, and know how to prevent, possible complications related to these procedures. In the case of operative hysteroscopy, the systemic effects of low-viscosity fluid uptake must be considered in order to prevent the complications in the patient. We report on two unusual clinical signs of intravascular absorption syndrome (IAS) that developed during an operative hysteroscopy with glycine 1.5% as the fluid of distension. Based on our experience, we recommend that practitioners reduce operating times, monitor fluid balances, check electrolytes and kinetic heart rates, and monitor for symptoms including otorrhagia and nosebleed, in order to identify and possibly prevent IAS due to an overload of low-viscosity fluids.


Assuntos
Epistaxe/etiologia , Histeroscopia/efeitos adversos , Idoso , Feminino , Humanos , Síndrome
2.
FASEB J ; 21(13): 3573-83, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17601985

RESUMO

Satellite cells are the main source of myogenic progenitors in postnatal skeletal muscle, but their use in cell therapy for muscle disorders is limited because these cells cannot be delivered through circulation and they are rapidly exhausted in severe myopathies. The search for alternative donor cells is ongoing, but none of the candidates so far show all the features required for successful colonization and repair of diseased muscle. In this study, we show that bisperoxovanadium, a phospho-tyrosine phosphatase inhibitor, induces myogenic cells to acquire a gene expression profile and a differentiation potential consistent with the phenotype of a circulating precursors, while maintaining their myogenic potential. These effects are mediated, at least in part, by NF-kappaB activation through the Tyr42-IkappaB-alpha phosphorylation, as shown by the expression of the dominant negative mutant form of the p50 NF-kappaB subunit. Moreover, when bisperoxovanadium-treated cells are injected into the femoral artery of alpha-sarcoglican null dystrophic mice, they are able to circulate and to reach muscle tissue; importantly, they contribute to muscle regeneration, as shown by the expression of alpha-sarcoglican in some fibers. Our observations indicate that bisperoxovanadium, or similar compounds, may prove very valuable to obtain and to expand, from committed cells, multipotent cell populations suitable for gene-cell therapy applications and may help to understand the molecular basis of genome reprogramming and "stem-ness."


Assuntos
Inibidores Enzimáticos/farmacologia , Coração/efeitos dos fármacos , Miocárdio/citologia , Células-Tronco Pluripotentes/citologia , Proteínas Tirosina Fosfatases/antagonistas & inibidores , Compostos de Vanádio/farmacologia , Animais , Sequência de Bases , Ciclo Celular , Linhagem Celular , Primers do DNA , Citometria de Fluxo , Imunofluorescência , Expressão Gênica , Camundongos , Miocárdio/metabolismo , Fenótipo , Células-Tronco Pluripotentes/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
3.
Cancer Res ; 61(1): 2-7, 2001 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-11196162

RESUMO

Histone deacetylase (HDAC)-dependent transcriptional repression of the retinoic acid (RA)-signaling pathway underlies the differentiation block of acute promyelocytic leukemia. RA treatment relieves transcriptional repression and triggers differentiation of acute promyelocytic leukemia blasts, leading to disease remission. We report that transcriptional repression of RA signaling is a common mechanism in acute myeloid leukemias (AMLs). HDAC inhibitors restored RA-dependent transcriptional activation and triggered terminal differentiation of primary blasts from 23 AML patients. Accordingly, we show that AML1/ETO, the commonest AML-associated fusion protein, is an HDAC-dependent repressor of RA signaling. These findings relate alteration of the RA pathway to myeloid leukemogenesis and underscore the potential of transcriptional/differentiation therapy in AML.


Assuntos
Antineoplásicos/farmacologia , Inibidores de Histona Desacetilases , Leucemia Mieloide Aguda/enzimologia , Leucemia Mieloide Aguda/patologia , Leucemia Mielomonocítica Aguda/enzimologia , Leucemia Mielomonocítica Aguda/patologia , Transdução de Sinais/efeitos dos fármacos , Tretinoína/farmacologia , Acetilação , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Subunidade alfa 2 de Fator de Ligação ao Core , Inibidores Enzimáticos/farmacologia , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Histona Desacetilases/fisiologia , Histonas/metabolismo , Humanos , Ácidos Hidroxâmicos/farmacologia , Leucemia Mieloide Aguda/genética , Leucemia Mielomonocítica Aguda/genética , Proteínas de Fusão Oncogênica/biossíntese , Proteínas de Fusão Oncogênica/genética , Proteína 1 Parceira de Translocação de RUNX1 , Transdução de Sinais/fisiologia , Fatores de Transcrição/biossíntese , Fatores de Transcrição/genética , Ativação Transcricional/efeitos dos fármacos , Ativação Transcricional/fisiologia , Tretinoína/fisiologia , Células Tumorais Cultivadas
4.
Facts Views Vis Obgyn ; 8(1): 3-7, 2016 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-27822346

RESUMO

OBJECTIVE: To evaluate the accuracy of ultrasound in visualizing placental cord insertion (PCI) at different gestational ages in order to recommend the most feasible period during pregnancy to identify it. Secondary aim was to propose a predictive algorithm for PCI visualization. METHODS: We performed a single-center, prospective cohort study. We enrolled patients with singleton low-risk pregnancies who underwent fetal ultrasound scan at different gestational ages. We excluded patients with body mass index of 30 Kg/m2 or more, uterine fibroids larger than 5 cm, high-risk pregnancies, fetal weight lower than < 10° percentile or higher than > 90° percentile, increased ("deep pocket" > 80 mm) or decreased ("deep pocket" < 20 mm) amniotic fluid. RESULTS: Among the 468 recruited patients, the visualization of PCI was not possible in 5.77% of the cases. Furthermore, we showed that PCI visualization was lower as the gestational age increased (p = 0.049) and more difficult in case of posterior placenta (p = 0.001). CONCLUSIONS: PCI should be evaluated in the first trimester or as early as possible during the second trimester. Moreover, we propose a feasible model to predict the possibility of PCI visualization according to gestational age and uterine site of implantation.

5.
Cell Death Differ ; 10(2): 175-84, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12700645

RESUMO

Apoptosis control in adult testis is crucial to achieve normal spermatogenesis. In this study c-FLIP, an apoptosis-modulating protein, was investigated. In Western blot and immunohistochemical analyses, the 55 KDa c-FLIP long isoform (c-FLIP(L)) was found to be expressed strongly in spermatocytes and spermatids, at low levels in spermatogonia and at almost undetectable levels in Sertoli cells. This expression pattern was confirmed by Northern blot analyses. Further experiments carried out on GC-1spg germ cell line revealed that reducing c-FLIP(L) expression increases Fas-dependent apoptosis. Conversely, restoring c-FLIP(L) expression reduces this response to control levels. Caspase-10 expression was found to match c-FLIP(L) expression pattern; further, caspase-10 activation upon anti-Fas treatment inversely correlated with c-FLIP(L) expression. Finally, TUNEL staining of seminiferous tubules incubated with anti-Fas antibody showed that apoptosis occurs mostly in basally located germ cells, indicating that such cells, expressing low levels of c-FLIP(L), are sensitive to Fas-mediated apoptosis. These data indicate for the first time that c-FLIP(L) might control germ cell apoptosis and caspase activity in the adult testis.


Assuntos
Apoptose , Proteínas de Transporte/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular , Testículo/metabolismo , Animais , Proteína Reguladora de Apoptosis Semelhante a CASP8 e FADD , Caspases/metabolismo , Linhagem Celular/efeitos dos fármacos , Células Cultivadas , Ativação Enzimática , Células Germinativas/citologia , Masculino , Camundongos , Camundongos Endogâmicos , Oligonucleotídeos Antissenso/farmacologia , Isoformas de Proteínas/metabolismo , Túbulos Seminíferos , Células de Sertoli/citologia , Células de Sertoli/metabolismo , Espermátides/citologia , Espermátides/metabolismo , Espermatócitos/citologia , Espermatócitos/metabolismo , Espermatogônias/citologia , Espermatogônias/metabolismo , Testículo/química , Testículo/citologia , Receptor fas/metabolismo
6.
Int J Gynaecol Obstet ; 91(3): 233-7, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16214144

RESUMO

OBJECTIVE: To study the utility of Doppler velocimetry and computerized cardiotocography in the management of intrauterine growth restriction and prediction of neonatal outcome. PATIENTS AND METHODS: Seventy-two pregnant women with fetuses showing growth restriction and delivered within 48 h of their last Doppler velocimetry evaluation. The last computerized cardiotocographic trace from these fetuses was used for statistical analysis, and the last trace from the healthy fetuses of 93 consecutive women undergoing cesarean section was used as control. Umbilical artery pulsatility index (UA PI), middle cerebral artery pulsatility index (MCA PI), UA PI/MCA PI ratio, and uterine artery resistance index (Ut RI) were assessed. RESULTS: Among women with growth-restricted fetuses, all parameters were significantly higher in those who had hypertension; and in those who had diabetes, only the UA PI/MCA ratio was significantly higher. Umbilical artery PI values and the UA PI/MCA ratio were higher in those who had a nonreassuring result to computerized nonstress test immediately before delivery. A multiple logistic analysis showed that the UA PI/MCA ratio was the only Doppler velocimetry parameter predicting cardiotocographic nonreactivity; furthermore, the predictivity of extended newborn hospitalization (longer than 15 days) was verified, with a sensitivity of 56% and a specificity of 92% when the ratio was higher than 1.26. CONCLUSION: The MCA PI of fetuses with growth restriction should be assessed. The UA PI/MCA ratio is predictive of a nonreactive computerized cardiotocography trace and of prolonged neonatal hospitalization.


Assuntos
Retardo do Crescimento Fetal/diagnóstico , Artéria Cerebral Média/fisiologia , Resultado da Gravidez , Fluxo Pulsátil/fisiologia , Ultrassonografia Pré-Natal , Artérias Umbilicais/fisiologia , Adulto , Velocidade do Fluxo Sanguíneo , Cardiotocografia , Feminino , Humanos , Hipertensão Induzida pela Gravidez , Recém-Nascido , Gravidez , Terceiro Trimestre da Gravidez , Gravidez em Diabéticas , Ultrassonografia Doppler
7.
Clin Chim Acta ; 207(1-2): 87-97, 1992 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-1591868

RESUMO

Three SP1-containing factors from pooled term pregnancy sera were subjected to crossed immunoelectrophoresis. New patterns as far as electrophoretic mobilities and shapes of the immunoprecipitates were revealed. The appearance of an additional anodic radioimmunoassayable activity in agarose electrophoresis of mixed SP1-alpha and SP1-beta suggested a binding capacity of SP1-alpha for SP1-beta determinants. In the serum of a single patient at the third trimester of pregnancy we also found two SP1 variants, possessing little radioimmunological reactivity and with crossed immunoelectrophoretic characteristics quite different from those of the 'usual' alpha and beta SP1 forms. These results suggest that, in this particular case, the overall SP1 production cannot be evaluated by competitive binding assay and, that in general, SP1 is a complex antigen the heterogeneity of which can be determined following adsorption of some beta epitopes to another serum protein.


Assuntos
Glicoproteínas beta 1 Específicas da Gravidez/química , Feminino , Humanos , Imunoeletroforese Bidimensional , Gravidez , Glicoproteínas beta 1 Específicas da Gravidez/metabolismo
8.
Cell Death Dis ; 4: e926, 2013 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-24263100

RESUMO

MicroRNAs are key regulators of many biological processes, including cell differentiation. These small RNAs exert their function assembled in the RNA-induced silencing complexes (RISCs), where members of Argonaute (Ago) family of proteins provide a unique platform for target recognition and gene silencing. Here, by using myeloid cell lines and primary blasts, we show that Ago2 has a key role in human monocytic cell fate determination and in LPS-induced inflammatory response of 1,25-dihydroxyvitamin D3 (D3)-treated myeloid cells. The silencing of Ago2 impairs the D3-dependent miR-17-5p/20a/106a, miR-125b and miR-155 downregulation, the accumulation of their translational targets AML1, VDR and C/EBPß and monocytic cell differentiation. Moreover, we show that Ago2 is recruited on miR-155 host gene promoter and on the upstream region of an overlapping antisense lncRNA, determining their epigenetic silencing, and miR-155 downregulation. These findings highlight Ago2 as a new factor in myeloid cell fate determination in acute myeloid leukemia cells.


Assuntos
Proteínas Argonautas/metabolismo , Leucemia Mieloide Aguda/metabolismo , Proteínas Argonautas/genética , Western Blotting , Proteínas Estimuladoras de Ligação a CCAAT/genética , Proteínas Estimuladoras de Ligação a CCAAT/metabolismo , Calcitriol/farmacologia , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Linhagem Celular Tumoral , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , Células HL-60 , Humanos , Leucemia Mieloide Aguda/genética , MicroRNAs/genética , Receptores de Calcitriol/genética , Receptores de Calcitriol/metabolismo
9.
Cell Death Dis ; 3: e413, 2012 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-23096114

RESUMO

Blocks in genetic programs required for terminal myeloid differentiation and aberrant proliferation characterize acute myeloid leukemia (AML) cells. 1,25-Dihydroxy-vitamin D3 (VitD3) arrests proliferation of AML cells and induces their differentiation into mature monocytes. In a previous study, we showed that miR-26a was induced upon VitD3-mediated monocytic differentiation. Here, we identify E2F7 as a novel target of miR-26a. We show that E2F7 significantly promotes cell cycle progression and inhibits monocytic differentiation of AML cells. We also demonstrate that E2F7 binds the cyclin-dependent kinase inhibitor p21(CIP1/WAF1) (cyclin-dependent kinase inhibitor 1A) promoter repressing its expression. Moreover, interfering with E2F7 expression results in inhibition of c-Myc (v-myc myelocytomatosis viral oncogene homolog) transcriptional activity. This leads to the downregulation of c-Myc transcriptional target miR-17-92 cluster, whose expression has a well-defined role in contributing to block monocytic differentiation and sustain AML cell proliferation. Finally, we show that the expression of E2F7 is upregulated in primary blasts from AML patients. Thus, these findings indicate that the newly identified miR-26a target E2F7 might have an important role in monocytic differentiation and leukemogenesis.


Assuntos
Diferenciação Celular , Proliferação de Células , Fator de Transcrição E2F7/genética , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/fisiopatologia , MicroRNAs/genética , Monócitos/citologia , Ciclo Celular , Células Cultivadas , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Fator de Transcrição E2F7/metabolismo , Células HL-60 , Humanos , Leucemia Mieloide Aguda/metabolismo , MicroRNAs/metabolismo , Monócitos/metabolismo , Células U937
10.
Cell Death Differ ; 19(6): 1038-48, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22193543

RESUMO

p53 mutations have profound effects on non-small-cell lung cancer (NSCLC) resistance to chemotherapeutic treatments. Mutant p53 proteins are usually expressed at high levels in tumors, where they exert oncogenic functions. Here we show that p53R175H, a hotspot p53 mutant, induces microRNA (miRNA)-128-2 expression. Mutant p53 binds to the putative promoter of miR128-2 host gene, ARPP21, determining a concomitant induction of ARPP21 mRNA and miR-128-2. miR-128-2 expression in lung cancer cells inhibits apoptosis and confers increased resistance to cisplatin, doxorubicin and 5-fluorouracyl treatments. At the molecular level, miR-128-2 post-transcriptionally targets E2F5 and leads to the abrogation of its repressive activity on p21(waf1) transcription. p21(waf1) protein localizes to the cytoplasmic compartment, where it exerts an anti-apoptotic effect by preventing pro-caspase-3 cleavage. This study emphasizes miRNA-128-2 role as a master regulator in NSCLC chemoresistance.


Assuntos
Fator de Transcrição E2F5/metabolismo , MicroRNAs/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Apoptose/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Cisplatino/farmacologia , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Doxorrubicina/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Fluoruracila/farmacologia , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Regiões Promotoras Genéticas , RNA Mensageiro/metabolismo , Transcrição Gênica , Proteína Supressora de Tumor p53/genética
12.
Hum Reprod ; 22(11): 2868-78, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17855413

RESUMO

BACKGROUND: Semen is the major vehicle for HIV-1 infection as it contains free and cell-associated virions and infected cells. However, the presence of HIV-1 in spermatozoa has been a matter of debate, since the sperm cell fraction may contain somatic infected cells that jeopardize the attribution of the detected virus to the spermatozoa. METHODS: Spermatozoa from 12 HIV-1 seropositive subjects were purified by multilayered Percoll gradient followed by osmotic shock. Residual presence of non-seminal cells (NCS) in purified spermatozoa, was then evaluated by cytometric and molecular analysis. HIV-1 DNA was revealed by nested PCR and in situ PCR after sperm chromatin decondensation. DNA-fragmented ejaculated spermatozoa in semen of infected subjects were detected by terminal deoxynucleotidyl transferase-mediated dUDP nick-end labeling (TUNEL) analysis. RESULTS: Purification procedure adopted allowed complete removal of NCS. On purified sperm cells, HIV-1 DNA was detected in 5 out of 12 subjects by nested-PCR. On crude semen of 10 out of 12 subjects, HIV-1 DNA was in situ detected in a small percentage of abnormal spermatozoa with a wide range of structural alterations. TUNEL analysis revealed an increased percentage of DNA-fragmented ejaculated spermatozoa in semen of infected subjects. CONCLUSIONS: We report molecular evidence demonstrating that HIV-1 infected subjects can ejaculate small amounts of HIV-1 DNA-positive abnormal spermatozoa. Their possible role in HIV-1 sexual transmission remains to be clarified.


Assuntos
DNA Viral/metabolismo , Soropositividade para HIV/metabolismo , Soropositividade para HIV/virologia , HIV-1/metabolismo , Sêmen/virologia , Espermatozoides/virologia , Adulto , Separação Celular , Fragmentação do DNA , Citometria de Fluxo , Humanos , Marcação In Situ das Extremidades Cortadas , Masculino , Pessoa de Meia-Idade , Osmose , Povidona/farmacologia , Dióxido de Silício/farmacologia
13.
Hum Reprod ; 20(10): 2814-20, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15979995

RESUMO

BACKGROUND: The aim of this study is to shed some light on the role of the Fas system in human semen, by investigating whether there is an association between the expression of the molecules regulating the Fas system [membrane-bound Fas ligand (mFasL), soluble Fas ligand (sFasL) and matrilysin, the metalloprotease cleaving mFasL to sFasL] and sperm parameters. METHODS: We investigated, by flow cytometric analysis, the presence of FasL on spermatozoa from normozoospermic and teratozoospermic subjects and, by western blot, the presence of sFasL and matrilysin in the seminal plasma of the same samples as well as on samples from azoospermic subjects. The enzymatic activity of matrilysin was examined by gel zymography. RESULTS: We observed that sperm cells expressed mFasL in 22% of normozoospermic men, whereas it was absent from spermatozoa from teratozoospermic patients. Higher levels of sFasL and augmented enzymatic activity of matrilysin were found in azoospermic samples. CONCLUSIONS: The presence of mFasL on sperm from normozoospermic men and its absence in pathological samples emphasize the role of the Fas system in human semen. Moreover, the presence of both sFasL and matrilysin in seminal plasma implies a fine regulation of the function of the Fas system and, consequently, of the apoptotic process in the human genital tract.


Assuntos
Metaloproteinase 7 da Matriz/biossíntese , Glicoproteínas de Membrana/biossíntese , Oligospermia/metabolismo , Sêmen/metabolismo , Fatores de Necrose Tumoral/biossíntese , Adulto , Apoptose , Western Blotting , Caseínas/química , Linhagem Celular Tumoral , Membrana Celular/metabolismo , Proteína Ligante Fas , Citometria de Fluxo , Humanos , Concentração de Íons de Hidrogênio , Infertilidade Masculina , Masculino , Metaloproteinase 7 da Matriz/química , Glicoproteínas de Membrana/química , Glicoproteínas de Membrana/metabolismo , Oligospermia/enzimologia , Sêmen/enzimologia , Espermatozoides/metabolismo , Testículo/metabolismo , Fatores de Necrose Tumoral/química , Fatores de Necrose Tumoral/metabolismo
14.
Thorax ; 33(1): 31-42, 1978 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-644538

RESUMO

Six female Wistar albino rats were exposed to the hypoxia of a simulated altitude of 5500 m, three for a period of one week and three for a month. They developed ultrastructural changes in the pulmonary trunk consisting of evaginations of muscle cells of its media through gaps in the internal elastic lamina to press into the underlying endothelial cells. Such evaginations were usually devoid of myofilaments and organelles. Some appeared so electron-lucent as to be unrecognisable as muscle apart from the unequivocal connection with the parent smooth muscle cells. Elsewhere we have demonstrated that muscular evaginations in normal pulmonary blood vessels are an artefact brought about by collapse of lung tissue and that they can be avoided by distending the lung. Hence in the present investigation, in which the pulmonary trunk was fixed in distension, the evaginations are interpreted as indicating contraction of the muscle cells able to overcome the distending force. We interpret them as evidence of constriction of muscle cells in the media of the pulmonary trunk in response to hypoxia.


Assuntos
Hipóxia/fisiopatologia , Músculo Liso/fisiopatologia , Artéria Pulmonar/fisiopatologia , Vasoconstrição , Animais , Citoplasma/ultraestrutura , Tecido Elástico/ultraestrutura , Endotélio/ultraestrutura , Feminino , Contração Muscular , Músculo Liso/ultraestrutura , Artéria Pulmonar/ultraestrutura , Ratos
15.
J Biol Chem ; 273(13): 7566-71, 1998 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-9516459

RESUMO

Tumor necrosis factor-alpha (TNF-alpha) is a pleiotropic cytokine that elicits a large number of biological effects. However, the intracellular signaling mechanisms that are responsible for the TNF-alpha effects remain largely unknown. We have previously demonstrated that cultured mouse Sertoli cells, after TNF-alpha treatment, increase the surface expression of adhesion molecules such as intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) and interleukin-6 (IL-6) production (Riccioli, A., Filippini, A., De Cesaris, P., Barbacci, E., Stefanini, M., Starace, G., and Ziparo, E. (1995) Proc. Natl. Acad. Sci. U.S.A. 92, 5808-5812). Here, we show that, in cultured Sertoli cells, TNF-alpha activates the mitogen-activated protein kinase pathway (p38, c-Jun N-terminal protein kinase/stress-activated protein kinase, and the p42/p44 mitogen-activated protein kinases) as revealed by an increased phosphorylation of p38, activating transcription factor-2, c-Jun, and Elk-1. Furthermore, our data indicate that the biological effects induced by TNF-alpha in Sertoli cells (enhancement of ICAM-1, VCAM-1, and IL-6 expression) depend on the activation of different signaling pathways. SB203580, a highly specific p38 inhibitor, does not affect ICAM-1 and VCAM-1 expression, but strongly inhibits IL-6 production. Moreover, interferon-gamma, which up-regulates adhesion molecule expression and reduces IL-6 production, does not induce phosphorylation of p38. Our data strongly support the hypothesis that, in response to TNF-alpha, activation of p38 leads to IL-6 production, whereas ICAM-1 and VCAM-1 expression could be induced by activation of the c-Jun N-terminal protein kinase/stress-activated protein kinase pathway.


Assuntos
Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Molécula 1 de Adesão Intercelular/biossíntese , Interleucina-6/biossíntese , Proteínas Quinases Ativadas por Mitógeno , Células de Sertoli/metabolismo , Transdução de Sinais , Fator de Necrose Tumoral alfa/farmacologia , Molécula 1 de Adesão de Célula Vascular/biossíntese , Fator 2 Ativador da Transcrição , Animais , Separação Celular , Células Cultivadas , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Ativação Enzimática , Inibidores Enzimáticos/farmacologia , Citometria de Fluxo , Imidazóis/farmacologia , Interferon gama/farmacologia , Proteínas Quinases JNK Ativadas por Mitógeno , Zíper de Leucina , Ligantes , Masculino , Camundongos , Fosforilação , Piridinas/farmacologia , Células de Sertoli/efeitos dos fármacos , Fatores de Transcrição/metabolismo , Regulação para Cima , Proteínas Quinases p38 Ativadas por Mitógeno
16.
J Chromatogr B Biomed Sci Appl ; 704(1-2): 25-34, 1997 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-9518157

RESUMO

The method presented can easily produce milligram amounts of glycodelin from pregnancy endometrium, with a 19% yield. It involves anion-exchange chromatography, gel permeation and chromatofocusing; it results in one stainable band at Mr 28,000 after sodium dodecyl sulphate-polyacrylamide electrophoresis, as well as after immunoblot analysis, performed using an affinity-purified IgG fraction from an antiserum against glycodelin. In spite of this, the corresponding gel isoelectric focusing pattern gives four stainable bands with pI values between 4.55 and 5.2. Western immunoblot analysis of tissue extracts indicates the presence of glycodelin epitopes associated with materials heavier than the native protein. Circular dichroism spectra of the highly purified protein in water solutions indicate a large amount of beta-sheet conformation, whereas those obtained with different proportions of 2-propanol in water, show an increased proportion of alpha-helix conformation.


Assuntos
Endométrio/química , Glicoproteínas/isolamento & purificação , Proteínas da Gravidez/isolamento & purificação , Ânions , Western Blotting , Cromatografia em Gel , Cromatografia por Troca Iônica , Dicroísmo Circular , Eletroforese em Gel de Poliacrilamida , Feminino , Glicodelina , Glicoproteínas/química , Humanos , Focalização Isoelétrica , Ponto Isoelétrico , Peso Molecular , Gravidez , Proteínas da Gravidez/química , Estrutura Secundária de Proteína
17.
J Immunol ; 165(2): 743-9, 2000 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-10878347

RESUMO

Sertoli cells have long been considered to be involved in the regulation of the immune response in the testis. More recently, the Fas system has been implicated in the maintenance of the immune privilege in the testis as well as in the regulation of germ cell apoptosis. However, the control of Fas and Fas ligand (FasL) expression in the testis remains unknown. In the present study, we demonstrate that cultured mouse Sertoli cells constitutively express a low level of membrane-bound Fas protein, but not a soluble form of Fas. Sertoli cells stimulated with TNF-alpha and IFN-gamma markedly increase the expression of both soluble and membrane-bound Fas in a dose-dependent manner. The up-regulated membrane-bound Fas protein is functionally active because it induces a significant level of Sertoli cell death in the presence of Neuro-2a FasL+ effector cells. Interestingly, the soluble form of Fas, which is induced by the same cytokines but has an antiapoptotic effect, is also functional. In fact, conditioned media from TNF-alpha-stimulated Sertoli cell cultures inhibit Neuro-2a FasL+-induced cell death. Taken together, our data suggest a possible regulatory role of TNF-alpha and IFN-gamma on Fas-mediated apoptosis in the testis through disruption of the balance between different forms of Fas.


Assuntos
Interferon gama/fisiologia , Túbulos Seminíferos/imunologia , Túbulos Seminíferos/metabolismo , Fator de Necrose Tumoral alfa/fisiologia , Receptor fas/biossíntese , Adjuvantes Imunológicos/fisiologia , Animais , Células Cultivadas , Meios de Cultivo Condicionados/metabolismo , Citocinas/fisiologia , Citotoxicidade Imunológica , Epitélio/imunologia , Epitélio/metabolismo , Proteína Ligante Fas , Regulação da Expressão Gênica/imunologia , Ligantes , Masculino , Glicoproteínas de Membrana/biossíntese , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/fisiologia , Camundongos , Isoformas de Proteínas/biossíntese , Isoformas de Proteínas/genética , RNA Mensageiro/biossíntese , Túbulos Seminíferos/citologia , Células de Sertoli/imunologia , Células de Sertoli/metabolismo , Solubilidade , Transcrição Gênica/imunologia , Receptor fas/genética , Receptor fas/metabolismo , Receptor fas/fisiologia
18.
Proc Natl Acad Sci U S A ; 98(6): 3316-21, 2001 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-11248076

RESUMO

The testis is the main source of Fas ligand (FasL) mRNA in rodents; it is generally believed that this molecule, expressed on bordering somatic Sertoli cells, bestows an immune-privileged status in the testis by eliminating infiltrating inflammatory Fas-bearing leukocytes. Our results demonstrate that the attribution of testicular expression of FasL to Sertoli cells is erroneous and that FasL transcription instead occurs in meiotic and postmeiotic germ cells, whereas the protein is only displayed on mature spermatozoa. These findings point to a significant role of the Fas system in the biology of mammalian reproduction.


Assuntos
Glicoproteínas de Membrana/metabolismo , Espermatozoides/metabolismo , Testículo/metabolismo , Animais , Células Cultivadas , Proteína Ligante Fas , Expressão Gênica , Masculino , Glicoproteínas de Membrana/genética , Camundongos , Ratos , Ratos Wistar , Células de Sertoli/citologia , Células de Sertoli/metabolismo , Espermatozoides/citologia , Testículo/crescimento & desenvolvimento
19.
Eur J Nucl Med ; 22(11): 1326-9, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8575486

RESUMO

High-affinity bacterially expressed antibody fragments can nowadays be cloned from established hybridomas or, more conveniently, isolated directly from antibody libraries displayed on filamentous phage. Such antibodies can be tagged with C-terminal peptide tags containing one cysteine residue, which represents a convenient functionalisation site for a number of applications, including technetium-99m labelling. Here we describe a simple one-step method for 99mTc labelling of cysteine-tagged recombinant antibodies with more than 50% radionuclide incorporation. The labelled antibodies displayed full retention of immuoreactivity and good stability.


Assuntos
Fragmentos de Imunoglobulinas , Marcação por Isótopo/métodos , Tecnécio , Anticorpos Antibacterianos , Afinidade de Anticorpos , Imunoconjugados , Proteínas Recombinantes
20.
Hum Reprod Update ; 7(5): 444-9, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11556490

RESUMO

It has long been known that the testis is an immunologically privileged site in the body, and that human seminal plasma possesses a generalized immunosuppressive activity. Multiple factors participate in the establishment of immunotolerance in the testis: the blood-tubular barrier; the local production of immunosuppressive molecules by Sertoli cells; and the Fas system as regulator of immunological homeostasis in both physiological and pathological conditions. Cytokine-induced up-regulation of Fas as well as of integrin ligands, which are known to be specific binding molecules for lymphocytes on the Sertoli cell surface, indicates that the 'nursing' cells of seminiferous epithelium might be important in the impairment of immune privilege, causing autoimmune orchitis. In addition, the soluble form of Fas-ligand protein present in the seminal plasma of infertile patients might suggest a role for this immunomodulatory protein in male infertility. Finally, an understanding of the mechanisms underlying immune privilege in the testis and in semen might help to clarify how cells expressing 'non-self' antigens (such as male gametes) can escape the immune system in both the male and female genital tracts.


Assuntos
Imunidade , Técnicas Reprodutivas , Espermatozoides/imunologia , Feminino , Fertilização in vitro , Humanos , Masculino , Reprodução/fisiologia
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