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1.
J Endocrinol Invest ; 45(1): 29-41, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34128215

RESUMO

PURPOSE: First-generation somatostatin analogs, octreotide (OCT) and lanreotide, are the cornerstone for the medical treatment of growth hormone (GH)-secreting pituitary tumors. A new multireceptor analog, such as pasireotide (PAS), showed better activity than OCT in long-term treatment of patients with acromegaly, but modulation of intracellular key processes is still unclear in vitro. In this study, we evaluated the antitumor activity of OCT and PAS in two GH-secreting pituitary tumor cell lines, GH3 and GH4C1, after a long-term incubation. METHODS: The effects of PAS and OCT on the cell viability, cell cycle, apoptosis, GH secretion, and tumor-induced angiogenesis have been evaluated through a colorimetric method (MTS Assay), DNA flow cytometry with propidium iodide, and Annexin V-FITC/propidium iodide staining, ELISA assay and zebrafish platform, respectively. RESULTS: PAS showed a more potent antitumor activity compared to OCT in GH3 cell line exerted through inhibition of cell viability, perturbation of cell cycle progression, and induction of apoptosis after 6 days of incubation. A concomitant decrease in GH secretion has been observed after 2 days of incubation only with PAS. No effect on tumor-induced angiogenesis has been reported after treatment with OCT or PAS in zebrafish/tumor xenograft model. CONCLUSION: Long-term incubation with PAS showed a more potent antitumor activity than that reported after OCT in GH3 cells, mainly modulated by a cell cycle perturbation and a relevant induction in apoptosis.


Assuntos
Adenoma/patologia , Adenoma Hipofisário Secretor de Hormônio do Crescimento/patologia , Octreotida/farmacologia , Somatostatina/análogos & derivados , Animais , Animais Geneticamente Modificados , Apoptose/efeitos dos fármacos , Embrião não Mamífero , Peptídeos Cíclicos , Ratos , Somatostatina/farmacologia , Somatotrofos/efeitos dos fármacos , Somatotrofos/metabolismo , Somatotrofos/patologia , Fatores de Tempo , Células Tumorais Cultivadas , Peixe-Zebra/embriologia
2.
Lett Appl Microbiol ; 73(2): 139-148, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33843058

RESUMO

Infections caused by KPC-producing Klebsiella pneumoniae (Kp-KPC) are associated with high mortality rates due to the increased number of resistant isolates and the scarcity of therapeutic options. This scenario reinforces the urgent need for new chemotherapeutics. Herein, we investigated the effects of 1,10-phenanthroline-5,6-dione (phendione) and its metal-based complexes, [Cu(phendione)3 ](ClO4 )2 .4H2 O (Cu-phendione) and [Ag(phendione)2 ]ClO4 (Ag-phendione), both alone and also combined with carbapenems (meropenem (MEM), and imipenem), against 46 clonally distinct clinical strains of Kp-KPC. All isolates were found to be multidrug resistant in accordance with their susceptibility patterns by disk diffusion method. Compounds geometric mean (GM)-MIC and GM-MBC values (µmol l-1 ), respectively, were: phendione, 42·06 and 71·27; Cu-phendione, 9·88 and 13·75; and Ag-phendione, 10·10 and 13·06. Higher synergism rates of MEM-containing combinations were observed by the checkerboard assay, particularly with the two metal complexes. Moreover, drug combinations were able to re-sensitize 87% of the phenotypically non-susceptible strains. Time-kill studies, with MEM plus Cu-phendione or Ag-phendione, indicated that combinations with 0·5× MIC of each agent produce synergistic effects after 9-12 h. The MEM plus Ag-phendione eradicated about 106  CFU per ml of bacteria. These findings support the effectiveness of the re-sensitizing combinatorial approach and provide evidence that phendione-based compounds offer real promise in the fight against Kp-KPC infections.


Assuntos
Carbapenêmicos/farmacologia , Complexos de Coordenação/farmacologia , Infecções por Klebsiella/tratamento farmacológico , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/efeitos dos fármacos , Fenantrolinas/farmacologia , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/farmacologia , Farmacorresistência Bacteriana Múltipla , Sinergismo Farmacológico , Humanos , Imipenem/farmacologia , Meropeném/farmacologia , Testes de Sensibilidade Microbiana , beta-Lactamases/genética , beta-Lactamases/metabolismo , beta-Lactamases/farmacologia
3.
J Endocrinol Invest ; 40(7): 761-770, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28247216

RESUMO

PURPOSE: Type I interferons (IFN-α and IFN-ß) are a class of cytokines that exert several biological activities, such as modulation of cell proliferation and differentiation and of the immune system. Although these cytokines interact with a common receptor complex, IFN-ß showed a more potent antitumor activity than IFN-α in several tumor models. New recombinant human IFN-ß products, such as IFN-ß1a and IFN-ß1b, have been produced in order to improve the stability and bioavailability of natural IFN-ß. In this report, we analyzed the effects of recombinant IFN-ß1a on the cell proliferation of two human androgen-resistant prostate cancer cell lines with neuroendocrine differentiation (DU-145, PC-3) and related mechanisms of action. METHODS: The effects of IFN-ß1a on the cell growth proliferation, cell cycle, and apoptosis have been evaluated in DU-145 and PC-3 cells through MTT assay, DNA flow cytometry with propidium iodide, and Annexin V-FITC/propidium iodide staining, respectively. Moreover, the expression of neuron-specific enolase (NSE), cleaved caspase-3, caspase-8, and PARP was evaluated through Western blotting. RESULTS: IFN-ß1a showed a significant anti-proliferative activity in both androgen-resistant cell lines. This effect was related to cell cycle perturbation and induction in apoptosis, as shown by flow cytometric analysis, the activation of caspase-3 and caspase-8 and PARP cleavage during incubation with IFN-ß1a. Moreover, this cytokine reduced the expression of NSE in both cell lines. CONCLUSIONS: Recombinant IFN-ß1a (Rebif) showed a potent in vitro anti-proliferative activity in androgen-resistant prostate cancer cells, and it could represent a promising tool for the treatment of this tumor.


Assuntos
Antineoplásicos/farmacologia , Diferenciação Celular/efeitos dos fármacos , Interferon beta-1a/farmacologia , Tumores Neuroendócrinos/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Humanos , Masculino , Tumores Neuroendócrinos/patologia , Neoplasias de Próstata Resistentes à Castração/patologia , Células Tumorais Cultivadas
4.
Curr Opin Rheumatol ; 27(5): 476-82, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26125104

RESUMO

PURPOSE OF REVIEW: Many advancements in our understanding of the pathogenic mechanisms of the antiphospholipid syndrome (APS) have been accomplished over the recent months. Such progresses are paralleled by the development of innovative pharmacological tools that could provide novel therapeutic windows in APS management. The most recent and innovative findings about the biologic effects of antiphospholipid antibodies (aPLs) and the treatment APS will be hereby critically appraised. RECENT FINDINGS: Antibodies against the domain I of ß2 glycoprotein I (ß2GPI) are increasingly recognized as the main pathogenic subset; pioneer therapeutic options exploiting the pathogenicity of anti-domain I antibodies have been developed. AnnexinA2 and toll-like receptor (TLR)4 have been identified as the main receptors for ß2GPI/anti-ß2GPI antibodies on target cells; additional co-receptors might include TLR1, TLR2 and TLR6. Upon binding, aPLs engage intracellular mediators as nuclear factor kappa B and mammalian target of rapamycin, which provide potential therapeutic targets. Current innovative treatment options include novel oral anticoagulants and the complement inhibitor eculizumab. The addition to standard treatment of pleiotropic agents such as hydroxychloroquine, statins and vitamin D could allow better disease control. SUMMARY: The lively and intense research in the APS field opens new frontiers in aPL pathogenic mechanisms, as well as diagnosis and treatment of the syndrome. VIDEO ABSTRACT: http://links.lww.com/COR/A26.


Assuntos
Síndrome Antifosfolipídica/imunologia , Anticorpos Antifosfolipídeos/imunologia , Síndrome Antifosfolipídica/terapia , Autoimunidade , Humanos
5.
Opt Lett ; 40(22): 5287-90, 2015 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-26565856

RESUMO

The observation of the electro-optic effect in strained silicon waveguides has been considered a direct manifestation of an induced χ(2) nonlinearity in the material. In this work, we perform high-frequency measurements on strained silicon racetrack resonators. Strain is controlled by a mechanical deformation of the waveguide. It is shown that any optical modulation vanishes, independent of the applied strain, when the applied voltage varies much faster than the carrier effective lifetime and that the DC modulation is also largely independent of the applied strain. This demonstrates that plasma carrier dispersion is responsible for the observed electro-optic effect. After normalizing out free-carrier effects, our results set an upper limit of (8±3) pm/V to the induced high-speed effective χeff,zzz(2) tensor element at an applied stress of -0.5 GPa. This upper limit is about 1 order of magnitude lower than previously reported values for static electro-optic measurements.

6.
J Autoimmun ; 55: 42-50, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24685231

RESUMO

The thrombogenic effect of ß2-glycoprotein I (ß2GPI)-dependent anti-phospholipid antibodies (aPL) in animal models was found to be LPS dependent. Since ß2GPI behaves as LPS scavenger, LPS/ß2GPI complex was suggested to account for in vitro cell activation through LPS/TLR4 involvement being LPS the actual bridge ligand between ß2GPI and TLR4 at least in monocytes/macrophages. However, no definite information is available on the interaction among ß2GPI, LPS and endothelial TLR4 in spite of the main role of endothelial cells (EC) in clotting. To analyse at the endothelial level the need of LPS, we investigated the in vitro interaction of ß2GPI with endothelial TLR4 and we assessed the role of LPS in such an interaction. To do this, we evaluated the direct binding and internalization of ß2GPI by confocal microscopy in living TLR4-MD2 transfected CHO cells (CHO/TLR4-MD2) and ß2GPI binding to CHO/TLR4-MD2 cells and human umbilical cord vein EC (HUVEC) by flow cytometry and cell-ELISA using anti-ß2GPI monoclonal antibodies in the absence or presence of various concentrations of exogenous LPS. To further investigate the role of TLR4, we performed anti-ß2GPI antibody binding and adhesion molecule up-regulation in TLR4-silenced HUVEC. Confocal microscopy studies show that ß2GPI does interact with TLR4 at the cell membrane and is internalized in cytoplasmic granules in CHO/TLR4-MD2 cells. ß2GPI binding to CHO/TLR4-MD2 cells and HUVEC is also confirmed by flow cytometry and cell-ELISA, respectively. The interaction between ß2GPI and TLR4 is confirmed by the reduction of anti-ß2GPI antibody binding and by the up-regulation of E-selectin or ICAM-1 by TLR4 silencing in HUVEC. ß2GPI binding is not affected by LPS at concentrations comparable to those found in both ß2GPI and antibody preparations. Only higher amount of LPS that can activate EC and up-regulate TLR4 expression are found to increase the binding. Our findings demonstrate that ß2GPI interacts directly with TLR4 expressed on EC, and that such interaction may contribute to ß2GPI-dependent aPL-mediated EC activation. At variance of monocytic cells, we also showed a threshold effect for the action of LPS, that is able to enhance anti-ß2GPI antibody EC binding only at cell activating concentrations, shown to increase TLR4 expression. This in vitro model may explain why LPS behaves as a second hit increasing the expression of ß2GPI in vascular tissues and triggering aPL-mediated thrombosis in experimental animals.


Assuntos
Anticorpos Antifosfolipídeos/imunologia , Células Endoteliais da Veia Umbilical Humana/imunologia , Lipopolissacarídeos/toxicidade , Trombose/imunologia , Receptor 4 Toll-Like/imunologia , beta 2-Glicoproteína I/imunologia , Animais , Células CHO , Cricetinae , Cricetulus , Células Endoteliais da Veia Umbilical Humana/patologia , Humanos , Modelos Imunológicos , Ligação Proteica , Trombose/induzido quimicamente , Trombose/genética , Trombose/patologia , Receptor 4 Toll-Like/genética , beta 2-Glicoproteína I/genética
7.
Opt Express ; 22(12): 14505-16, 2014 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-24977546

RESUMO

Optically induced thermal and free carrier nonlinearities in silicon micro-ring resonator influence their behavior. They can be either deleterious by making them instable and by driving their resonances out of the designed wavelengths, or enabler of different applications. Among the most interesting one, there are optical bistability and self induced oscillations. These lead to all optical logic, signal modulation, optical memories and applications in neural networks. Here, we theoretically and experimentally demonstrate that when many resonators are coupled together, thermal and free carrier nonlinearities induce also chaos. The chaotic dynamics are deeply analyzed using experimentally reconstructed phase space trajectories and the tool of Lyapunov exponents.

8.
Lupus ; 23(12): 1262-4, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25228721

RESUMO

The international consensus for the classification of antiphospholipid syndrome (APS) requires clinical and laboratory criteria to be considered at an equal level for diagnosing APS. Thus, detection of antiphospholipid antibodies (aPL) being a hallmark of APS has been the object of intensive investigation over the past 40 years. However, appropriate detection of aPL still remains a laboratory challenge due to their heterogeneity comprising autoantibodies reactive to different phospholipid-binding plasma proteins, such as beta-2 glycoprotein I (ß2GPI) and prothrombin. The relevance of aPL interacting with phospholipids other than cardiolipin (CL, diphosphatidylglycerol), such as phosphatidylserine (PS), remains elusive with regard to the diagnosis of APS. Recently, the concept of aPL profiling has been introduced to assess the risk of thrombotic complications in patients with APS. New assay techniques, apart from enzyme-linked immunosorbent assays (ELISAs) recommended by the international consensus for the classification of APS, have been proposed for multiplexing of aPL testing. Line immunoassays (LIAs) employing a novel hydrophobic solid phase for the simultaneous detection of different aPL seem to be an intriguing alternative. We evaluated a novel multiplex LIA employing a hydrophobic membrane coated with different phospholipid (PL)-binding proteins or PLs. The performance characteristics of this new multiplexing assay technique demonstrated its usefulness for aPL profiling.


Assuntos
Síndrome Antifosfolipídica/imunologia , Autoanticorpos/sangue , Anticorpos Anticardiolipina/sangue , Anticorpos Antifosfolipídeos/sangue , Ensaio de Imunoadsorção Enzimática , Humanos , beta 2-Glicoproteína I/imunologia
9.
Lupus ; 23(12): 1302-4, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25228733

RESUMO

Antiphospholipid syndrome (APS) is a systemic autoimmune disease characterized by thrombotic events and/or pregnancy morbidity in the persistent presence of antiphospholipid antibodies (aPL). aPL targeting ß2 glycoprotein I (anti-ß2GPI Abs) provide the main pathogenic autoantibody subset. In monocytes, platelets and endothelial cells (ECs), the interaction of circulating aPL with membrane-bound ß2GPI results in cell activation, and EC perturbation provides an important player in clotting. Several receptors have been suggested to mediate ß2GPI/EC binding. AnnexinA2 provides a high-affinity binding site for ß2GPI but, since it does not span the cell membrane, an adaptor protein is required to trigger signal. Consistent evidence supports the role of Toll-like receptor (TLR) 4 as co-receptor for ß2GPI on ECs. ß2GPI was recently reported to behave as lipopolysaccharide (LPS) scavenger. In monocytes, TLR4 activation was shown to be apparent, due to LPS/ß2GPI complexes. Conversely, our findings in ECs demonstrate that ß2GPI interacts directly with TLR4, and that such interaction may contribute to ß2GPI-dependent aPL-mediated EC activation. LPS enhanced anti-ß2GPI Ab binding to EC only at cell-activating concentrations, able to up-regulate TLR4. This in vitro model may explain why LPS behaves as a second hit increasing the expression of ß2GPI in vascular tissues and triggering aPL-mediated thrombosis in vivo.


Assuntos
Células Endoteliais/fisiologia , Receptor 4 Toll-Like/fisiologia , beta 2-Glicoproteína I/fisiologia , Anexina A2/fisiologia , Anticorpos Antifosfolipídeos/imunologia , Humanos , Lipopolissacarídeos/farmacologia
10.
Lupus ; 23(12): 1317-9, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25228737

RESUMO

International standards for anti-beta2 glycoprotein I (anti-ß2GPI) testing are needed. We evaluated the suitability of polyclonal/monoclonal candidate reference materials (RM) for the assay. IgG/IgM anti-ß2GPI were affinity-purified (AP) from high-positive antiphospholipid syndrome sera and IgG from HCAL clone supernatant. Igs were tested for purity by SDS-PAGE, pooled, concentrated, sterile-filtered and the protein concentration determined. One unit was defined as the binding activity of 1 µg/ml of AP anti-ß2GPI Ig. IgG/IgM RM were each assigned a unit value using the respective AP material as a calibrator. Polyclonal/monoclonal RM and 30 samples were evaluated for linearity, unit equivalency and commutability. Polyclonal AP material was assigned a value of 100 U IgG and 15 U IgM anti-ß2GPI, respectively. IgG-RM had a value of 270 IgG and the IgM-RM of 220.3 IgM anti-ß2GPI U. The linearity (R (2)) of each RM curve for the various assays ranged from 0.96 to 0.99. Commutability samples fit very well within 95% prediction intervals and had excellent correlation when comparing assays. IgG and IgM polyclonal and IgG monoclonal RM displayed excellent linearity and commutability, being good candidates for better standardization of anti-ß2GPI immunoassays.


Assuntos
Autoanticorpos/sangue , Imunoglobulina G/sangue , Imunoglobulina M/sangue , beta 2-Glicoproteína I/imunologia , Humanos , Imunoensaio/normas , Padrões de Referência
11.
Mol Genet Genomic Med ; 12(2): e2387, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38337160

RESUMO

BACKGROUND: Disease-related variants in PHEX cause XLH by an increase of fibroblast growth factor 23 (FGF23) circulating levels, resulting in hypophosphatemia and 1,25(OH)2 vitamin D deficiency. XLH manifests in early life with rickets and persists in adulthood with osseous and extraosseous manifestations. Conventional therapy (oral phosphate and calcitriol) improves some symptoms, but evidence show that it is not completely effective, and it can lead to nephrocalcinosis (NC) and hyperparathyroidism (HPT). Burosumab (anti-FGF23 antibody) has shown to be effective and safety in the clinical trials. METHODS: The current real-world collaborative study evaluated genetic, clinical and laboratory data of XLH Brazilian adult patients treated with burosumab. RESULTS: Nineteen unrelated patients were studied. Patients reported pain, limb deformities and claudication, before burosumab initiation. 78% of them were previously treated with conventional therapy. The severity of the disease was moderate to severe (15 patients with score >5). At the baseline, 3 patients presented NC (16.7%) and 12 HPT (63%). After 16 ± 8.4 months under burosumab, we observed a significant: increase in stature (p = 0.02), in serum phosphate from 1.90 ± 0.43 to 2.67 ± 0.52 mg/dL (p = 0.02); in TmP/GFR from 1.30 ± 0.46 to 2.27 ± 0.64 mg/dL (p = 0.0001), in 1,25 (OH)2 D from 50.5 ± 23.3 to 71.1 ± 19.1 pg/mL (p = 0.03), and a decrease in iPTH from 86.8 ± 37.4 pg/mL to 66.5 ± 31.1 (p = 0.002). Nineteen variants were found (10 novel). HPT tended to develop in patients with truncated PHEX variants (p = 0.06). CONCLUSIONS: This study confirms the efficacy and safety of burosumab on XLH adult patients observed in clinical trials. Additionally, we observed a decrease in iPTH levels in patients with moderate to severe HPT at the baseline.


Assuntos
Anticorpos Monoclonais Humanizados , Raquitismo Hipofosfatêmico Familiar , Adulto , Humanos , Raquitismo Hipofosfatêmico Familiar/tratamento farmacológico , Raquitismo Hipofosfatêmico Familiar/genética , Anticorpos Monoclonais/uso terapêutico , Brasil , Fatores de Crescimento de Fibroblastos/genética , Fatores de Crescimento de Fibroblastos/metabolismo , Fosfatos/uso terapêutico
12.
J Cell Mol Med ; 16(7): 1563-72, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21883896

RESUMO

Everolimus, an mTOR inhibitor, which has been demonstrated to induce anti-tumour effects in different types of neuroendocrine tumours, has never been evaluated in patients with medullary thyroid cancer (MTC). The aim of this study was to evaluate the in vitro and in vivo effects of everolimus in combination with octreotide in MTC. Two patients with progressive metastatic MTC and high calcitonin levels were treated with everolimus 5-10 mg/day. Both patients were under treatment with octreotide LAR at the study entry. An in vitro study was also performed to assess everolimus effects on MTC cell lines (TT and MZ-CRC-1 cells). A tumour response was observed in both patients. Serum calcitonin decreased by 86% in patient 1 and by 42% in patient 2. In TT and MZ-CRC-1 cells, everolimus induced a significant dose-dependent inhibition in cell proliferation. This effect seems to be related to a cell cycle arrest in G(0) /G(1) phase in both cell lines and to the induction of cellular senescence in TT cells. Everolimus in combination with octreotide may be active as anti-tumour therapy in patients with progressive metastatic MTC, suggesting to further evaluate this agent in MTC patients in a large prospective study.


Assuntos
Senescência Celular/efeitos dos fármacos , Sirolimo/análogos & derivados , Neoplasias da Glândula Tireoide/tratamento farmacológico , Idoso , Apoptose/efeitos dos fármacos , Western Blotting , Calcitonina/sangue , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Difosfonatos/farmacologia , Everolimo , Humanos , Imidazóis/farmacologia , Masculino , Pessoa de Meia-Idade , Sirolimo/farmacologia , Neoplasias da Glândula Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/patologia , Tireoidectomia/métodos , Resultado do Tratamento , Ácido Zoledrônico , beta-Galactosidase/metabolismo
13.
Lupus ; 21(7): 708-10, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22635208

RESUMO

Beta2 glycoprotein I (ß2GPI)-dependent antiphospholipid antibodies (aPLs) are the main pathogenic autoantibody population and at the same time the laboratory diagnostic tool for the antiphospholipid syndrome (APS). These antibodies are responsible for both the vascular and the obstetric manifestations of the syndrome but the pathogenic mechanisms behind these manifestations are not the same. For example, thrombotic events do not appear to play a major role in APS miscarriages and a direct reactivity of ß2GPI-dependent aPLs on decidual and trophoblast cells was reported. A local expression of ß2GPI on these tissues was reported both in physiological conditions and in APS women, thus explaining the local tropism of the autoantibodies. The two hit hypothesis was suggested to explain why the vascular manifestations of APS may occur only occasionally in spite of the persistent presence of aPLs. This is not apparently the case for the obstetric variant of the syndrome, making the difference even more striking. A different pathogenesis may also provide the rationale for the well-known fact that the vascular and the obstetric manifestations may occur independently although in a minority of cases.


Assuntos
Síndrome Antifosfolipídica/complicações , Complicações na Gravidez/imunologia , Trombose/imunologia , Anticorpos Antifosfolipídeos/imunologia , Feminino , Humanos , Gravidez , beta 2-Glicoproteína I/imunologia
14.
Arthritis Rheum ; 62(5): 1504-12, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20131286

RESUMO

OBJECTIVE: Heparin-binding epidermal growth factor-like growth factor (HB-EGF) plays a role in blastocyst implantation and is down-regulated in preeclampsia and in hypertensive pregnancy disorders associated with defective extravillous trophoblast invasion. Defective placentation and severe preeclampsia are also features of the antiphospholipid syndrome (APS). The purpose of this study was to investigate whether abnormal HB-EGF expression plays a pathogenic role in antiphospholipid antibody (aPL)-mediated defective placentation. METHODS: HB-EGF expression in placental tissue was evaluated by Western blotting and messenger RNA analysis in normal and APS placentae. Polyclonal IgG fractions or monoclonal beta(2)-glycoprotein I-dependent aPL and their respective controls were investigated for the following 4 features: their binding to human trophoblast monolayers, as determined by cell enzyme-linked immunosorbent assay (ELISA); their effect on HB-EGF expression by Western blotting in trophoblast cell extracts as well as by ELISA as a protein secreted in the culture supernatants; their inhibitory effect on in vitro trophoblast invasiveness, as evaluated by Matrigel assay; and their inhibitory effect on matrix metalloproteinase (MMP) levels, as measured by gelatin zymography. Experiments were also performed in the presence of serial concentrations of heparin or recombinant HB-EGF. RESULTS: Placental APS tissue displayed reduced expression of HB-EGF. Polyclonal and monoclonal aPL bound to trophoblast monolayers and significantly reduced the in vitro synthesis and secretion of HB-EGF. Heparin inhibited aPL binding and restored HB-EGF expression in a dose-dependent manner. Addition of recombinant HB-EGF reduced the in vitro aPL-induced inhibition of Matrigel invasiveness as well as MMP-2 levels. CONCLUSION: These preliminary findings suggest that the reduction of aPL-mediated HB-EGF represents an additional mechanism that is responsible for the defective placentation associated with APS and that heparin protects from aPL-induced damage by inhibiting antibody binding.


Assuntos
Síndrome Antifosfolipídica , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Doenças Placentárias , Adulto , Anticorpos Antifosfolipídeos/imunologia , Anticorpos Antifosfolipídeos/farmacologia , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/farmacologia , Anticoagulantes/farmacologia , Síndrome Antifosfolipídica/imunologia , Síndrome Antifosfolipídica/metabolismo , Síndrome Antifosfolipídica/patologia , Western Blotting , Células Cultivadas , Regulação para Baixo/imunologia , Feminino , Expressão Gênica/imunologia , Heparina de Baixo Peso Molecular/farmacologia , Fator de Crescimento Semelhante a EGF de Ligação à Heparina , Humanos , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Projetos Piloto , Doenças Placentárias/imunologia , Doenças Placentárias/metabolismo , Doenças Placentárias/patologia , Gravidez , RNA Mensageiro/metabolismo , Trofoblastos/citologia , Trofoblastos/efeitos dos fármacos , Trofoblastos/imunologia , beta 2-Glicoproteína I/imunologia
15.
Lupus ; 19(4): 453-6, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20353987

RESUMO

Antiphospholipid antibodies (aPL) are associated with recurrent miscarriages and pregnancy complications, however their pathogenic mechanisms are still matter of research. Thrombotic events at the placental level cannot explain all of the clinical manifestations. It has been suggested that aPL may be responsible for a local acute inflammatory response mediated by complement activation and neutrophil infiltration eventually leading to fetal loss. However histological and immunohistological studies on human placental samples do support such a mechanism only in part and with no any clear relationship with the pregnancy outcome. A direct effect of aPL on both maternal and fetal placental tissues has been reported through the reactivity of the antibodies with beta2 glycoprotein I (beta2GPI) expressed on the cell membranes. These events do not require an inflammatory response and can be in part related to the inhibition of growth factors favouring a physiological placentation. Understanding the different pathogenic mechanisms of aPL-associated miscarriages may help in improving our therapeutic approach particularly in recurrent cases not responsive to the usual treatment.


Assuntos
Aborto Habitual/imunologia , Anticorpos Antifosfolipídeos/imunologia , Complicações na Gravidez/imunologia , Aborto Habitual/etiologia , Síndrome Antifosfolipídica/complicações , Síndrome Antifosfolipídica/imunologia , Membrana Celular/imunologia , Ativação do Complemento/imunologia , Feminino , Humanos , Inflamação/etiologia , Inflamação/imunologia , Infiltração de Neutrófilos/imunologia , Gravidez , Complicações na Gravidez/etiologia , Trombose/etiologia , Trombose/imunologia , beta 2-Glicoproteína I/imunologia
16.
Nat Commun ; 11(1): 2505, 2020 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-32427911

RESUMO

While integrated photonics is a robust platform for quantum information processing, architectures for photonic quantum computing place stringent demands on high quality information carriers. Sources of single photons that are highly indistinguishable and pure, that are either near-deterministic or heralded with high efficiency, and that are suitable for mass-manufacture, have been elusive. Here, we demonstrate on-chip photon sources that simultaneously meet each of these requirements. Our photon sources are fabricated in silicon using mature processes, and exploit a dual-mode pump-delayed excitation scheme to engineer the emission of spectrally pure photon pairs through inter-modal spontaneous four-wave mixing in low-loss spiralled multi-mode waveguides. We simultaneously measure a spectral purity of 0.9904 ± 0.0006, a mutual indistinguishability of 0.987 ± 0.002, and  >90% intrinsic heralding efficiency. We measure on-chip quantum interference with a visibility of 0.96 ± 0.02 between heralded photons from different sources.

17.
Sci Transl Med ; 11(496)2019 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-31189718

RESUMO

Candida vaginitis is a frequent clinical diagnosis with up to 8% of women experiencing recurrent vulvovaginal candidiasis (RVVC) globally. RVVC is characterized by at least three episodes per year. Most patients with RVVC lack known risk factors, suggesting a role for genetic risk factors in this condition. Through integration of genomic approaches and immunological studies in two independent cohorts of patients with RVVC and healthy individuals, we identified genes and cellular processes that contribute to the pathogenesis of RVVC, including cellular morphogenesis and metabolism, and cellular adhesion. We further identified SIGLEC15, a lectin expressed by various immune cells that binds sialic acid-containing structures, as a candidate gene involved in RVVC susceptibility. Candida stimulation induced SIGLEC15 expression in human peripheral blood mononuclear cells (PBMCs) and a polymorphism in the SIGLEC15 gene that was associated with RVVC in the patient cohorts led to an altered cytokine profile after PBMC stimulation. The same polymorphism led to an increase in IL1B and NLRP3 expression after Candida stimulation in HeLa cells in vitro. Last, Siglec15 expression was induced by Candida at the vaginal surface of mice, where in vivo silencing of Siglec15 led to an increase in the fungal burden. Siglec15 silencing was additionally accompanied by an increase in polymorphonuclear leukocytes during the course of infection. Identification of these pathways and cellular processes contributes to a better understanding of RVVC and may open new therapeutic avenues.


Assuntos
Candida albicans/patogenicidade , Genômica/métodos , Leucócitos Mononucleares/metabolismo , Leucócitos Mononucleares/microbiologia , Animais , Candidíase Vulvovaginal/genética , Candidíase Vulvovaginal/metabolismo , Citocinas/metabolismo , Feminino , Predisposição Genética para Doença/genética , Humanos , Camundongos , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo
18.
Hum Reprod ; 23(12): 2701-8, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18716040

RESUMO

BACKGROUND: Celecoxib, a selective cyclooxygenase (COX)-2 inhibitor, also has anti-proliferative properties and pro-apoptotic effects on different in vivo and in vitro models, two actions that may be efficacious in therapy for endometriosis. We evaluated the effects of celecoxib on apoptosis and proliferation, and vascular endothelial growth factor (VEGF) production and COX-2 expression and activity in endometrial epithelial cells (EECs). METHODS AND RESULTS: Thirty-two endometriosis and 13 control women were included in the study. EECs from eutopic endometrium and control biopsies were cultured with different doses of celecoxib. Celecoxib at 50, 75 and 100 microM (versus vehicle control) inhibited EEC proliferation in cultures from controls (P < 0.05, P < 0.01 and P < 0.01, respectively) and patients with endometriosis (P < 0.05, P < 0.01 and P < 0.01), as assessed by (3)H-thymidine uptake. Celecoxib at 50, 75 and 100 microM induced apoptosis in EEC from controls (P < 0.05, P < 0.001 and P < 0.001) and patients with endometriosis (P < 0.001, P < 0.001 and P < 0.01), as revealed by the Acridine Orange-Ethidium Bromide technique. Western blot analysis showed that celecoxib was effective at increasing COX-2 protein at 100 microM in EEC from endometriosis patients (P < 0.05). In EEC from endometriosis patients, celecoxib at 25, 50 and 100 microM was also effective in reducing COX-2 activity, reflected in the reduction of prostaglandin E(2) (PGE(2)) synthesis (P < 0.001), and VEGF secretion (P < 0.001; P < 0.05 and P < 0.001), assessed by enzyme-linked immunosorbent assay. Exogenous PGE(2) did not reverse celecoxib-induced growth inhibition. CONCLUSIONS: This study suggests a direct effect of celecoxib on reduction of endometrial growth and supports further research on selective COX-2 inhibition as a novel therapeutic modality in endometriosis.


Assuntos
Inibidores de Ciclo-Oxigenase 2/farmacologia , Endometriose/patologia , Endométrio/citologia , Células Epiteliais/efeitos dos fármacos , Pirazóis/farmacologia , Sulfonamidas/farmacologia , Apoptose/efeitos dos fármacos , Celecoxib , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Ciclo-Oxigenase 2/biossíntese , Dinoprostona/biossíntese , Dinoprostona/farmacologia , Endometriose/tratamento farmacológico , Endometriose/fisiopatologia , Endométrio/efeitos dos fármacos , Feminino , Humanos , Imuno-Histoquímica , Infertilidade Feminina , Pirazóis/uso terapêutico , Sulfonamidas/uso terapêutico
19.
Ann N Y Acad Sci ; 1069: 364-76, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16855163

RESUMO

Antiphospholipid antibodies (aPLs) reacting with beta-2 glycoprotein I (beta2GPI) have been associated with recurrent fetal loss and pregnancy complications. The aim of the study was to investigate whether aPLs with anti-beta2GPI specificity induce apoptosis of human trophoblasts in vitro. To this end, human anti-beta2GPI monoclonal IgM derived from a patient with antiphospholipid syndrome and a human irrelevant monoclonal IgM were incubated with human trophoblast cell cultures for 24, 48, and 72 h. In all the cultures we evaluated: (i) Bcl-2 and Bax mRNA and protein expression by Western blot and reverse transcription polymerase chain reaction (RT-PCR), respectively; (ii) DNA fragmentation by a commercial ELISA kit and by agarose gel electrophoresis; and (iii) the percentage of cells reactive with the monoclonal antibody (MAb) M30 by indirect immunofluorescence. The results were: Bcl-2/Bax ratio increased in untreated trophoblast cells during the time of culture, showing the highest values detectable after 72 h (2.68 and 2.28 at protein and mRNA levels, respectively). Cell incubation with anti-beta2GPI MAbs induced a significant Bcl-2/Bax ratio reduction in comparison with untreated cells (1.22 and 1.28 at protein and mRNA levels, respectively, after 72 h incubation). No significant difference was detected after cell exposure to irrelevant MAbs. However, neither DNA fragmentation nor increase in cells positive for the caspase-cleaved epitope of cytokeratin 18 cytoskeletal protein (M30) was found. In Conclusion, anti-beta2GPI antibodies react with trophoblast cells and reduce the Bcl-2/Bax ratio, but without any clear apoptotic effect.


Assuntos
Anticorpos/imunologia , Apoptose , Glicoproteínas/imunologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Trofoblastos/citologia , Trofoblastos/metabolismo , Proteína X Associada a bcl-2/metabolismo , Células Cultivadas , Expressão Gênica , Humanos , Proteínas Proto-Oncogênicas c-bcl-2/genética , RNA Mensageiro/genética , Trofoblastos/imunologia , Proteína X Associada a bcl-2/genética , beta 2-Glicoproteína I
20.
Bioresour Technol ; 97(14): 1756-60, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16162407

RESUMO

Dried and re-hydrated biomass of Spirulina platensis was employed as a sorbent in tests of copper removal from water. Biomass re-hydrated for 24 h before use exhibited a shorter adsorption time as well as an increased percentage removal when compared with simply dried biomass. The combined effects of the concentrations of re-hydrated biomass (from 1.0 to 4.0 g l-1) and copper (from 0.1 to 0.4 g l-1) were then investigated. Copper was almost entirely removed (91% removal) at relatively high biomass levels (X0>or=2.0 gDM l-1), while 1.0 gDM l-1 removed only 81% of copper present initially, suggesting a situation of excess metal with respect to the adsorption capacity of biomass. Additional tests performed with biomass re-hydrated for variable time demonstrated that no less than 48 h of this treatment are needed to ensure a satisfactory copper removal, while no significant improvement was detected using biomass re-hydrated for longer times.


Assuntos
Biomassa , Cobre/isolamento & purificação , Cianobactérias/metabolismo , Poluentes da Água/isolamento & purificação , Purificação da Água/métodos , Adsorção , Cianobactérias/crescimento & desenvolvimento
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