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2.
Eur Respir J ; 59(4)2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34475226

RESUMO

BACKGROUND: Survival after lung transplantation (LTx) is hampered by uncontrolled inflammation and alloimmunity. Regulatory T-cells (Tregs) are being studied as a cellular therapy in solid organ transplantation. Whether these systemically administered Tregs can function at the appropriate location and time is an important concern. We hypothesised that in vitro-expanded recipient-derived Tregs can be delivered to donor lungs prior to LTx via ex vivo lung perfusion (EVLP), maintaining their immunomodulatory ability. METHODS: In a rat model, Wistar Kyoto (WKy) CD4+CD25high Tregs were expanded in vitro prior to EVLP. Expanded Tregs were administered to Fisher 344 (F344) donor lungs during EVLP; left lungs were transplanted into WKy recipients. Treg localisation and function post-transplant were assessed. In a proof-of-concept experiment, cryopreserved expanded human CD4+CD25+CD127low Tregs were thawed and injected into discarded human lungs during EVLP. RESULTS: Rat Tregs entered the lung parenchyma and retained suppressive function. Expanded Tregs had no adverse effect on donor lung physiology during EVLP; lung water as measured by wet-to-dry weight ratio was reduced by Treg therapy. The administered cells remained in the graft at 3 days post-transplant where they reduced activation of intra-graft effector CD4+ T-cells; these effects were diminished by day 7. Human Tregs entered the lung parenchyma during EVLP where they expressed key immunoregulatory molecules (CTLA4+, 4-1BB+, CD39+ and CD15s+). CONCLUSIONS: Pre-transplant Treg administration can inhibit alloimmunity within the lung allograft at early time points post-transplant. Our organ-directed approach has potential for clinical translation.


Assuntos
Transplante de Pulmão , Linfócitos T Reguladores , Animais , Pulmão , Transplante de Pulmão/efeitos adversos , Perfusão/efeitos adversos , Ratos , Doadores de Tecidos
3.
Acta Virol ; 64(1): 10-19, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32180414

RESUMO

Andrias davidianus ranavirus 1R (ADRV-1R), a core gene of the family Iridoviridae, is predicted to encode a viral transcription factor (vTF) since the protein contains a virus late transcription factor-3 like (VLTF3 like) domain. However, its characteristics and function are still unclear. In this study, the transcription and expression of ADRV-1R were investigated in Chinese giant salamander thymus cells (GSTCs). ADRV-1R transcription starts 6 hours post-infection (hpi), while the protein expression starts 8 hpi. Drug inhibition assay showed that the transcripts are inhibited by cycloheximide (CHX), a de novo protein synthesis inhibitor, indicating that ADRV-1R is a viral delayed-early (DE) gene. Subcellular localization showed that ADRV-1R is distributed in the cell nucleus and cytoplasm. The effect of ADRV-1R overexpression on cell proliferation and virus titer was analyzed. ADRV-1R overexpression significantly promoted the cell proliferation starting at day 2. Flow cytometry analysis further indicated that the protein promotes the GSTC cell cycle progression from G1 phase into S phase (G1/S transition). Moreover, ADRV-1R overexperession significantly increased ADRV titer in GSTCs. The virus titer was 6.3-6.9-fold higher at 36 hpi and further after than the control GSTC lines. These data showed that ADRV-1R is a delayed-early protein promoting cell proliferation and virus titers. Keywords: ranavirus; Andrias davidianus ranavirus; core gene; cell cycle; cell proliferations.


Assuntos
Proliferação de Células , Infecções por Vírus de DNA , Ranavirus , Fase S , Fatores de Transcrição/genética , Proteínas Virais/genética , Animais , Células Cultivadas , Urodelos/virologia
4.
J Fish Biol ; 89(3): 1692-703, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27418461

RESUMO

This study represents the first report of a C-type lectin (ctl) in yellow catfish Tachysurus fulvidraco. The complete sequence of ctl complementary (c)DNA consisted of 685 nucleotides. The open reading frame potentially encoded a protein of 177 amino acids with a calculated molecular mass of c.y 20.204 kDa. The deduced amino-acid sequence contained a signal peptide and a single carbohydrate recognition domain with four cysteine residues and GlnProAsp (QPD) and TrpAsnAsp (WND) motifs. Ctl showed the highest identity (56.0%) to the predicted lactose binding lectin from channel catfish Ictalurus punctatus. Quantitative real-time (qrt)-PCR analysis showed that ctl messenger (m)RNA was constitutively expressed in all examined tissues in normal fish, with high expression in trunk kidney and head kidney, which was increased following Aeromonas hydrophila challenge in a duration-dependent manner. Purified recombinant Ctl (rCtl) from Escherichia coli BL21 was able to bind and agglutinate Gram-positive and Gram-negative bacteria in a calcium-dependent manner. These results suggested that Ctl might be a C-type lectin of T. fulvidraco involved in innate immune responses as receptors (PRR).


Assuntos
Peixes-Gato/genética , Peixes-Gato/metabolismo , Lectinas Tipo C/genética , Lectinas Tipo C/metabolismo , Aeromonas hydrophila/fisiologia , Aglutinação , Sequência de Aminoácidos , Animais , Bactérias/metabolismo , Peixes-Gato/classificação , Clonagem Molecular , Escherichia coli/genética , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/veterinária , Rim Cefálico/imunologia , Ictaluridae/genética , Imunidade Inata/imunologia , Lectinas Tipo C/química , Filogenia , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Homologia de Sequência de Aminoácidos
5.
Cell Death Dis ; 6: e1938, 2015 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-26492371

RESUMO

It is well established that BAX and BAK play crucial, overlapping roles in the intrinsic pathway of apoptosis. Gene targeted mice lacking both BAX and BAK have previously been generated, but the majority of these animals died perinatally. BOK is a poorly studied relative of BAX and BAK that shares extensive amino acid sequence homology to both proteins, but its function remains largely unclear to date. To determine whether BOK plays an overlapping role with BAX and BAK, we utilized a hematopoietic reconstitution model where lethally irradiated wild type mice were transplanted with Bok(-/-)Bax(-/-)Bak(-/-) triple knockout (TKO) fetal liver cells, and compared alongside mice reconstituted with a Bax(-/-)Bak(-/-) double knockout (DKO) hematopoietic compartment. We report here that mice with a TKO and DKO hematopoietic system died at a similar rate and much earlier than control animals, mostly due to severe autoimmune pathology. Both TKO and DKO reconstituted mice also had altered frequencies of various leukocyte subsets in the thymus, bone marrow and spleen, displayed leukocyte infiltrates and autoimmune pathology in multiple tissues, as well as elevated levels of anti-nuclear autoantibodies. Interestingly, the additional deletion of BOK (on top of BAX and BAK loss) led to a further increase in peripheral blood lymphocytes, as well as enhanced lymphoid infiltration in some organs. These findings suggest that BOK may have some functions that are redundant with BAX and BAK in the hematopoietic system.


Assuntos
Sistema Hematopoético/fisiologia , Proteínas Proto-Oncogênicas c-bcl-2/fisiologia , Proteína Killer-Antagonista Homóloga a bcl-2/fisiologia , Proteína X Associada a bcl-2/fisiologia , Animais , Apoptose/genética , Contagem de Células Sanguíneas , Quimera , Deleção de Genes , Técnicas de Inativação de Genes , Leucócitos/citologia , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteína Killer-Antagonista Homóloga a bcl-2/genética , Proteína Killer-Antagonista Homóloga a bcl-2/metabolismo , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo
6.
Cell Death Dis ; 4: e650, 2013 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-23744350

RESUMO

The multi-BCL-2 homology domain pro-apoptotic BCL-2 family members BAK and BAX have critical roles in apoptosis. They are essential for mitochondrial outer-membrane permeabilization, leading to the release of apoptogenic factors such as cytochrome-c, which promote activation of the caspase cascade and cellular demolition. The BOK protein has extensive amino-acid sequence similarity to BAK and BAX and is expressed in diverse cell types, particularly those of the female reproductive tissues. The BOK-deficient mice have no readily discernible abnormalities, and its function therefore remains unresolved. We hypothesized that BOK may exert functions that overlap with those of BAK and/or BAX and examined this by generating Bok(-/-)Bak(-/-) and Bok(-/-)Bax(-/-) mice. Combined loss of BOK and BAK did not elicit any noticeable defects, although it remains possible that BOK and BAK have critical roles in developmental cell death that overlap with those of BAX. In most tissues examined, loss of BOK did not exacerbate the abnormalities caused by loss of BAX, such as defects in spermatogenesis or the increase in neuronal populations in the brain and retina. Notably, however, old Bok(-/-)Bax(-/-) females had abnormally increased numbers of oocytes from different stages of development, indicating that BOK may have a pro-apoptotic function overlapping with that of BAX in age-related follicular atresia.


Assuntos
Proteínas Proto-Oncogênicas c-bcl-2/deficiência , Proteína Killer-Antagonista Homóloga a bcl-2/deficiência , Proteína X Associada a bcl-2/deficiência , Animais , Apoptose , Encéfalo/anormalidades , Encéfalo/metabolismo , Sobrevivência Celular , Células Cultivadas , Feminino , Linfócitos/fisiologia , Masculino , Camundongos , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Knockout , Células Mieloides/metabolismo , Folículo Ovariano/metabolismo , Folículo Ovariano/patologia , Proteínas Proto-Oncogênicas c-bcl-2/genética , Retina/anormalidades , Retina/metabolismo , Baço/metabolismo , Testículo/anormalidades , Testículo/metabolismo , Proteína Killer-Antagonista Homóloga a bcl-2/genética , Proteína X Associada a bcl-2/genética
7.
Cell Death Differ ; 20(6): 785-99, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23429263

RESUMO

The pro-apoptotic BCL-2 family member BOK is widely expressed and resembles the multi-BH domain proteins BAX and BAK based on its amino acid sequence. The genomic region encoding BOK was reported to be frequently deleted in human cancer and it has therefore been hypothesized that BOK functions as a tumor suppressor. However, little is known about the molecular functions of BOK. We show that enforced expression of BOK activates the intrinsic (mitochondrial) apoptotic pathway in BAX/BAK-proficient cells but fails to kill cells lacking both BAX and BAK or sensitize them to cytotoxic insults. Interestingly, major portions of endogenous BOK are localized to and partially inserted into the membranes of the Golgi apparatus as well as the endoplasmic reticulum (ER) and associated membranes. The C-terminal transmembrane domain of BOK thereby constitutes a 'tail-anchor' specific for targeting to the Golgi and ER. Overexpression of full-length BOK causes early fragmentation of ER and Golgi compartments. A role for BOK on the Golgi apparatus and the ER is supported by an abnormal response of Bok-deficient cells to the Golgi/ER stressor brefeldin A. Based on these results, we propose that major functions of BOK are exerted at the Golgi and ER membranes and that BOK induces apoptosis in a manner dependent on BAX and BAK.


Assuntos
Mitocôndrias/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Animais , Apoptose/fisiologia , Retículo Endoplasmático/metabolismo , Complexo de Golgi/metabolismo , Células HEK293 , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Proto-Oncogênicas c-bcl-2/deficiência , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteína Killer-Antagonista Homóloga a bcl-2/metabolismo , Proteína X Associada a bcl-2/metabolismo
8.
Water Sci Technol ; 65(8): 1412-9, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22466587

RESUMO

Mechanisms for low concentrations phosphorus removal in secondary effluent were studied, and a process was developed using limestone filters (LF), submerged macrophyte oxidation ponds (SMOPs) and a subsurface vertical flow wetland (SVFW). Pilot scale experimental models were applied in series to investigate the advanced purification of total phosphorus (TP) in secondary effluent at the Chengjiang sewage treatment plant. With a total hydraulic residence time (HRT) of 82.52 h, the average effluent TP dropped to 0.17 mg L(-1), meeting the standard for Class III surface waters. The major functions of the LF were adsorption and forced precipitation, with a particulate phosphorus (PP) removal of 82.93% and a total dissolved phosphorus (TDP) removal of 41.07%. Oxygen-releasing submerged macrophytes in the SMOPs resulted in maximum dissolved oxygen (DO) and pH values of 11.55 mg L(-1) and 8.10, respectively. This regime provided suitable conditions for chemical precipitation of TDP, which was reduced by a further 39.29%. In the SVFW, TDP was further reduced, and the TP removal in the final effluent reached 85.08%.


Assuntos
Fósforo/isolamento & purificação , Purificação da Água , Biodegradação Ambiental , Biomassa , Calamus/crescimento & desenvolvimento , Hydrocharitaceae/crescimento & desenvolvimento , Concentração de Íons de Hidrogênio , Oxigênio/análise , Projetos Piloto , Esgotos/análise , Áreas Alagadas
9.
Cell Death Differ ; 19(6): 915-25, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22281706

RESUMO

BOK/MTD was discovered as a protein that binds to the anti-apoptotic Bcl-2 family member MCL-1 and shares extensive amino-acid sequence similarity to BAX and BAK, which are essential for the effector phase of apoptosis. Therefore, and on the basis of its reported expression pattern, BOK is thought to function in a BAX/BAK-like pro-apoptotic manner in female reproductive tissues. In order to determine the function of BOK, we examined its expression in diverse tissues and investigated the consequences of its loss in Bok(-/-) mice. We confirmed that Bok mRNA is prominently expressed in the ovaries and uterus, but also observed that it is present at readily detectable levels in several other tissues such as the brain and myeloid cells. Bok(-/-) mice were produced at the expected Mendelian ratio, appeared outwardly normal and proved fertile. Histological examination revealed that major organs in Bok(-/-) mice displayed no morphological aberrations. Although several human cancers have somatically acquired copy number loss of the Bok gene and BOK is expressed in B lymphoid cells, we found that its deficiency did not accelerate lymphoma development in Eµ-Myc transgenic mice. Collectively, these results indicate that Bok may have a role that largely overlaps with that of other members of the Bcl-2 family, or may have a function restricted to specific stress stimuli and/or tissues.


Assuntos
Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Animais , Apoptose , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Células Mieloides/imunologia , Células Mieloides/metabolismo , Ovário/metabolismo , Ovário/patologia , Proteínas Proto-Oncogênicas c-bcl-2/deficiência , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , RNA Mensageiro/metabolismo , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Útero/metabolismo , Útero/patologia
10.
Chin J Physiol ; 44(3): 143-50, 2001 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-11767286

RESUMO

The electromechanical effects of 3-[[4-(2-methoxy phenyl)piperazin-1-yl]methyl]-5-(methylthio)-2,3-dihydroimidazo[1,2-c]quinazoline (DL-017), a newly synthesized quinazoline-derived antihypertensive agent, on mammalian cardiac tissues were evaluated. In driven canine Purkinje fibers, DL-017 decreased twitch tension, the maximal rate of upstroke of the action potential (Vmax), and intracellular Na+ activity (a(i)Na) in a concentration-dependent manner. The action potential duration was decreased in canine Purkinje fibers but increased in guinea pig papillary muscles. In guinea pig ventricular papillary muscles, phenylephrine in the presence of 1 microM propranolol increased the twitch tension in a concentration-dependent manner. At 10 microM, phenylephrine significantly decreased a(i)Na and shortened the action potential duration. DL-017 at 0.01 microM inhibited these phenylephrine-induced effects and shifted the concentration-dependent curve to the right. In sinoatrial nodes, DL-017 inhibited pacemaker activity, involving decreases in the slope of diastolic depolarization and Vmax and an increase in a delay of repolarization. These results suggest that, in addition to blockade of alpha1-adrenoceptors and Na+ channels, DL-017 reduces cardiac excitability and contractility in association with inhibition of slow inward Ca2+ and outward K+ channels. Since two order higher concentrations are required, the contribution of DL-017 to cardiac depressant from blockade of ionic channels seems to be less important when this compound is clinically used as an antihypertensive drug.


Assuntos
Antagonistas de Receptores Adrenérgicos alfa 1 , Antagonistas Adrenérgicos alfa/farmacologia , Antiarrítmicos/farmacologia , Anti-Hipertensivos/farmacologia , Quinazolinas/farmacologia , Potenciais de Ação/efeitos dos fármacos , Animais , Relógios Biológicos/efeitos dos fármacos , Cães , Relação Dose-Resposta a Droga , Avaliação de Medicamentos , Feminino , Cobaias , Ventrículos do Coração/efeitos dos fármacos , Masculino , Modelos Animais , Músculos Papilares/efeitos dos fármacos , Ramos Subendocárdicos/efeitos dos fármacos , Nó Sinoatrial/efeitos dos fármacos , Nó Sinoatrial/fisiologia
11.
J Endocrinol ; 167(1): 61-9, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11018753

RESUMO

The interactive effects of pituitary adenylate cyclase-activating polypeptide (PACAP) and relaxin on the secretion of gelatinases, involved in matrix remodeling, in ovarian theca-interstitial cells and granulosa cells, were investigated in gonadotropin-primed immature rats. The gelatinases secreted from cultured cells were analyzed using gelatin zymography and scanning densitometry. We have previously shown that relaxin stimulated the secretion of a 71 kDa gelatinase, identified as a type IV collagenase (matrix metalloproteinase 2), in rat theca-interstitial cells. This study has demonstrated that PACAP27 and PACAP38, with similar potency, dose-dependently enhanced relaxin-induced secretion of 71 kDa gelatinase, whereas PACAP alone had no effect. In rat granulosa cells, both PACAP27 and PACAP38 alone dose-dependently increased the secretion of a 63 kDa gelatinase. In addition, this study has shown that cAMP signaling pathway mediators act similarly to that of PACAP on gelatinase secretion in rat ovarian cells. Cholera toxin, forskolin and 8-bromoadenosine cAMP augmented relaxin-induced secretion of 71 kDa gelatinase in theca-interstitial cells, and alone they had no effect. These mediators also increased the secretion of 63 kDa gelatinase in granulosa cells. It is well known that the increase in cellular cAMP level is associated with the morphological rounding-up phenomenon in granulosa cells. This study has shown that PACAP and cAMP pathway mediators, but not relaxin, could cause such changes in cell shape in granulosa cells as well as in theca-interstitial cells. In conclusion, this study provides original findings that PACAP acts synergistically with relaxin in stimulating the secretion of gelatinases in rat ovarian theca-interstitial cells and granulosa cells. This supports the idea that relaxin and PACAP may serve as ovarian physiological mediators of gonadotropin function in facilitating the ovulatory process. In addition, PACAP appears to act through the cAMP signaling pathway to affect biological functions in ovarian cells, whereas relaxin does not.


Assuntos
Neuropeptídeos/farmacologia , Ovário/efeitos dos fármacos , Relaxina/farmacologia , Animais , Técnicas de Cultura de Células , AMP Cíclico/fisiologia , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Feminino , Gelatinases/metabolismo , Ovário/citologia , Ovário/metabolismo , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/fisiologia
12.
Clin Exp Metastasis ; 18(6): 493-9, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11592306

RESUMO

The present study investigated the modulatory role of transforming growth factor beta 1 (TGFbeta1) on the secretion of matrix metalloproteinases (MMPs) and tested whether the altered secretion of MMPs could directly affect the invasive behavior of ovarian cancer cells. To this aim, human ovarian cancer SKOV3 cells were treated once with vehicle or various concentrations of TGFbeta1 for 24 h. Gelatinase activities in conditioned media were analyzed by zymography and densitometry. TGFbeta1 dose-dependently stimulated the secretion of a 68-kDa gelatinase, which was characterized as an MMP because its activity was inhibited by a metalloproteinase inhibitor 1,10-phenanthroline, and by a synthetic MMP inhibitor BB3103. In addition, we used aminophenylmercuric acetate (APMA) to activate latent gelatinases. APMA time-dependently decreased the activity of 68-kDa gelatinase, and increased the activities of 64- and 62-kDa gelatinolytic bands. The 68-kDa gelatinase was further characterized as MMP2 (gelatinase A) by immunoblotting analysis. We then tested TGFbeta1 effect on the invasive potential of SKOV3 cells as assessed by the migration ability through reconstituted basement membrane, and further investigated whether TGFbeta1 may act through modulating the MMP activity to affect ovarian cancer cell invasion. The results show that TGFbeta1 stimulated the invasive behavior of SKOV3 cells, and that MMP inhibitor BB3103 abrogated this effect of TGFbeta1. In conclusion, this study indicates that TGFbeta1 may act partly through stimulating the secretion of MMP in promoting the invasive behavior of human ovarian cancer cells. Furthermore, this work supports the idea that specific MMP inhibitors of the hydroxamate class could be therapeutically useful in controlling cancer cell invasion/metastasis.


Assuntos
Ácidos Hidroxâmicos/farmacologia , Metaloproteinase 2 da Matriz/metabolismo , Neoplasias Ovarianas/patologia , Inibidores de Proteases/farmacologia , Fator de Crescimento Transformador beta/fisiologia , Western Blotting , Proteínas da Matriz Extracelular/metabolismo , Feminino , Humanos , Hidrólise , Inibidores de Metaloproteinases de Matriz , Invasividade Neoplásica , Neoplasias Ovarianas/enzimologia , Células Tumorais Cultivadas
13.
Br J Pharmacol ; 128(5): 999-1010, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10556937

RESUMO

1. Flavonoids display a wide range of pharmacological properties including anti-inflammatory. Anti-mutagenic, anti-carcinogenic and anti-cancer effects. Here, we evaluated the effects of eight flavonoids on the tumour cell proliferation, cellular protein phosphorylation, and matrix metalloproteinase (MMPs) secretion. 2. Of the flavonoids examined, luteolin (Lu) and quercetin (Qu) were the two most potent agents, and significantly inhibited A431 cell proliferation with IC50 values of 19 and 21 micronM, respectively. 3. The epidermal growth factor (EGF) (10 nM) promoted growth of A431 cells (+25+/-4.6%) and mediated epidermal growth factor receptor (EGFR) tyrosine kinase activity and autophosphorylation of EGFR were inhibited by Lu and Qu. At concentration of 20 micronM, both Lu and Qu markedly decreased the levels of phosphorylation of A431 cellular proteins, including EGFR. 4. A431 cells treated with Lu or Qu exhibited protuberant cytoplasmic blebs and progressive shrinkage morphology. Lu and Qu also time-dependently induced the appearance of a ladder pattern of DNA fragmentation, and this effect was abolished by EGF treatment. 5. The addition of EGF only marginally diminished the inhibitory effect of luteolin and quercetin on the growth rate of A431 cells, treatment of cellular proteins with EGF and luteolin or quercetin greatly reduced protein phosphorylation, indicating Lu and Qu may act effectively to inhibit a wide range of protein kinases, including EGFR tyrosine kinase. 6. EGF increased the levels of matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9), while Lu and Qu appeared to suppress the secretion of these two MMPs in A431 cells. 7. Examination of the relationship between the chemical structure and inhibitory effects of eight flavonoids reveal that the double bond between C2 and C3 in ring C and the OH groups on C3' and C4' in ring B are critical for the biological activities. 8. This study demonstrates that the inhibitory effects of Lu and Qu, and the stimulatory effects of EGF, on tumour cell proliferation, cellular protein phosphorylation, and MMP secretion may be mediated at least partly through EGFR. This study supports the idea that Lu and Qu may have potential as anti-cancer and anti-metastasis agents.


Assuntos
Inibidores Enzimáticos/farmacologia , Receptores ErbB/biossíntese , Flavonoides/farmacologia , Proteínas Tirosina Quinases/antagonistas & inibidores , Quercetina/farmacologia , Autorradiografia , Western Blotting , Divisão Celular/efeitos dos fármacos , Fragmentação do DNA , Densitometria , Eletroforese em Gel de Poliacrilamida , Humanos , Luteolina , Metaloproteinases da Matriz/metabolismo , Metástase Neoplásica/patologia , Fosforilação , Fosfotirosina/metabolismo , Testes de Precipitina , Células Tumorais Cultivadas
14.
J Mass Spectrom ; 32(9): 992-1001, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9311150

RESUMO

Windows 30 m/z units wide of ions generated in electrospray and sampled under lens conditions of nominally zero potential gradient conditions were mass selected with Q1 in a triple-quadrupole mass spectrometer, fragmented in Q2, and their product ions mass analysed with Q3. A variety of analytes (equine myoglobin, bovine insulin, leucine enkephalin and PPG 1000) were examined. The windows selected sometimes contained desolvated (bare) analyte ions; more often they did not and contained only 'background' ions. For protein samples, multiply charged product ions having m/z values both lower and higher than those of the precursor ions were observed even when the precursor ion window could not have contained naked protein dimer ions. To observe significant product ions, the precursor ion window typically contained ions residing within background 'humps' that trailed protein peaks. These ions were speculated to be diverse, solvated multimeric clusters of the analyte which fragmented in Q2 to yield the characteristic product ion spectra.


Assuntos
Espectrometria de Massas/instrumentação , Animais , Bovinos , Fenômenos Químicos , Físico-Química , Encefalina Leucina/análise , Encefalina Leucina/química , Cavalos , Insulina/análise , Insulina/química , Espectrometria de Massas/métodos , Mioglobina/análise , Mioglobina/química
15.
Biol Reprod ; 55(6): 1276-83, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8949884

RESUMO

There were two related objectives in this study. The first was to determine the influence of endogenous relaxin on ovulation in rats. The second was to investigate the effect of relaxin on the secretion of gelatinases involved in extracellular matrix remodeling from rat ovarian cells. Immature rats were primed s.c. with 10 IU eCG; 51 to 52 h later, a monoclonal antibody specific for rat relaxin (MCAR), a control antibody against fluorescein (MCAF), or PBS vehicle was administered via intraovarian bursal injection under anesthesia, and 15 IU hCG was injected i.p. immediately thereafter. Rats were killed 26 h later, and oviducts were isolated and examined under the microscope to determine the number of ovulated oocytes. MCAR (0.25 and 2.5 micrograms/ovary) partially suppressed gonadotropin-induced ovulation as compared to the value for PBS controls. There was no significant difference in the number of ovulated oocytes between animals treated with MCAF and PBS controls. Also, porcine relaxin, given s.c. immediately after MCAR treatment, could reverse the inhibitory effect of MCAR on ovulation. To examine a possible mechanism for the effect of relaxin on ovulation, granulosa cells and theca-interstitial cells were obtained from ovaries of eCG-primed immature rats. The gelatinases secreted from cultured cells were analyzed using gelatin zymography and scanning densitometry. In the granulosa cell culture, relaxin increased the secretion of two major gelatinases of about 92 and 63 kDa in a dose-and time-dependent manner within 24 h of treatment. In the theca-interstitial cell culture, relaxin induced dose- and time-dependent increases in the secretion of two other major gelatinases of about 76 and 71 kDa. These gelatinases were characterized as metalloproteinases but not serine/cysteine proteinases. Furthermore, an immunoblot study demonstrated that relaxin stimulated the secretion of a 72-kDa type IV collagenase-like substance from cultured theca-interstitial cells but not from granulosa cells. This study demonstrates several original findings. First, endogenous relaxin may facilitate the ovulatory process in rats. Second, exogenous relaxin exhibits a biological effect on cultured rat theca-interstitial cells in addition to granulosa cells. Third, exogenous relaxin regulates the secretion of different major forms of gelantinases from cultured rat granulosa cells and theca-interstitial cells. The study supports the idea that relaxin may play an autocrine/paracrine role that is involved in modulating ovarian function.


Assuntos
Gelatinases/metabolismo , Células da Granulosa/enzimologia , Ovulação/fisiologia , Relaxina/fisiologia , Células Tecais/enzimologia , Animais , Anticorpos Monoclonais/farmacologia , Células Cultivadas , Gonadotropina Coriônica/farmacologia , Matriz Extracelular/metabolismo , Feminino , Células da Granulosa/efeitos dos fármacos , Immunoblotting , Ratos , Ratos Sprague-Dawley , Relaxina/antagonistas & inibidores , Relaxina/farmacologia , Células Tecais/efeitos dos fármacos
16.
Hua Xi Yi Ke Da Xue Xue Bao ; 27(1): 97-9, 1996 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-9208632

RESUMO

Rabbit alveolar macrophages (AM) in vitro were used as a model in this wooddust toxicological experiment to study the effect of birchdust with different concentrations and exposure durations on the viability of AM and superoxide produced by AM. The results showed that the viability rates in three birchdust groups (400, 800, 1600 micrograms/ml) gradually decreased when the concentration at all the designed exposure durations (12, 18, 24 h) increased except the rates for the 6-hour period. On the contrary, the contents of superoxide (O2-.) at the first two durations (6, 12 h) increased rapidly and reached their highest level at the 18 hours. Moreover, the rapid increase of O2-. preceded the declination of viability rates, suggesting that birchdust toxicity in AM in vitro be probably related to dust-induced O2-. produced by AM.


Assuntos
Poeira/efeitos adversos , Macrófagos Alveolares/fisiologia , Superóxidos/metabolismo , Madeira , Animais , Sobrevivência Celular , Radicais Livres , Coelhos
17.
J Mass Spectrom ; 31(2): 159-68, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8799269

RESUMO

Collision-induced dissociation mass spectra of alkali metal-containing anionic tripeptides are reported. Both N-terminal and C-terminal product ions were observed from the precursor ions [M - 2H + X]- and [M - 3H + 2X]- where X stands for an alkali metal. The results are consistent with precursor ion structures in which an alkali metal ion is centrally located for bonding with the amino terminus, the amide nitrogen atoms, and an oxygen atom of the carboxylate terminus; the second alkali metal ion in [M - 3H + 2X]- is likely attached to the other oxygen atom of the carboxylate terminus.


Assuntos
Metais Alcalinos/análise , Oligopeptídeos/química , Sequência de Aminoácidos , Ânions/metabolismo , Espectrometria de Massas , Dados de Sequência Molecular , Estrutura Molecular , Oligopeptídeos/análise , Fragmentos de Peptídeos/química
18.
Hua Xi Yi Ke Da Xue Xue Bao ; 25(3): 333-6, 1994 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-7896256

RESUMO

The results of our in vitro study showed that Rhodesia chrysotile, X. K. chrysotile, UICC chrysotile, crocidolite and amosite could cause damage to calf thymus DNA by inducing the production of 8-hydroxy-2'-deoxyguanosine (8-OH-dG). After adding H2O2 and/or FeSO4, the production of 8-OH-dG, induced by asbestos fibers was significantly increased. The fiber of UICC crocidolite has the most untoward effect, that of UICC amosite comes next, and the three chrysotile fibers are the weakest ones. The effect of asbestos fibers on the production of 8-OH-dG has some relationship with hydroxy free radical and the type of asbestos. It is suggested that asbestos fibers could induce DNA point mutation through A.T and G.C transversion by the production of 8-OH-dG, which is related with the carcinogenesis of asbestos.


Assuntos
Amianto/toxicidade , Dano ao DNA , 8-Hidroxi-2'-Desoxiguanosina , Animais , Amianto Amosita/toxicidade , Asbesto Crocidolita/toxicidade , Asbestos Serpentinas/toxicidade , Bovinos , Cocarcinogênese , DNA/metabolismo , Desoxiguanosina/análogos & derivados , Desoxiguanosina/biossíntese , Sinergismo Farmacológico , Peróxido de Hidrogênio/farmacologia , Técnicas In Vitro , Compostos de Ferro/farmacologia
19.
Hua Xi Yi Ke Da Xue Xue Bao ; 25(1): 70-3, 1994 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-8070778

RESUMO

The effects of jute, ramee, flax dusts on alveolar macrophage (AM) were observed by cell culture. The results indicated that AM could be damaged by all of the three kinds of dusts. The viability was decreased. The activity of lactic dehydrogenase (LDH) and acid phosphatase (AcP) in the culture supernatant was increased. The morphology of AM was damaged. But the toxicity effect of the three dusts was less than that of SiO2 and chrysotile asbestos (CH) in the same dosage. Meanwhile, the functions of AM were changed. The levels of IgG, immunocomplex (IC) and histamine (HIS) were increased. As to the degree of toxicity and ability of stimulating AM to secrete biomedium by the three dusts, the effect of flax was weakest.


Assuntos
Poeira/efeitos adversos , Macrófagos Alveolares/metabolismo , Têxteis/toxicidade , Animais , Complexo Antígeno-Anticorpo/metabolismo , Bissinose/etiologia , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Masculino , Coelhos
20.
Chest ; 104(1): 303-4, 1993 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8325097

RESUMO

Extralobar pulmonary sequestration (EPS) is a rather uncommon congenital anomaly. Most patients are diagnosed in their early life or during the first decade because of the early appearance of symptoms, including feeding difficulty, cyanosis, and dyspnea, or because of symptoms arising from the associated congenital abnormalities. Extralobar pulmonary sequestration is more often found between the lower lobe and the diaphragm and is usually associated with other congenital abnormalities, but the case reported herein differs in these respects. In this report, an incidental finding of EPS is described in a 30-year-old Chinese man, where EPS presents as an anterior mediastinal mass roentgenographically. The mass was attached to the right suprahilar region by a fibrovascular pedicle which contained a small elastic artery, veins, and nerve bundles.


Assuntos
Sequestro Broncopulmonar/diagnóstico , Neoplasias do Mediastino/diagnóstico , Adulto , Sequestro Broncopulmonar/patologia , Diagnóstico Diferencial , Humanos , Pulmão/patologia , Masculino
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