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1.
Cryo Letters ; 43(6): 341-348, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36629829

RESUMO

BACKGROUND: Swietenia mahagoni wood is one of the most valuable in world trade and, as a result, natural populations have been decimated due to unsustainable harvesting. The decline in natural population levels is being exacerbated by climate change. In order to ensure the preservation of valuable genotypes, there is an urgent need to develop strategies to conserve the genetic diversity present within this species. At present, cryopreservation is the most viable option for the long-term storage of plant germplasm, particularly for long-lived species which are challenging to maintain in the field. OBJECTIVE: To cryopreserve intact seeds of S. mahagoni, with the dual goal of retaining the biosynthetic capacity of plants, which is critical since this species is highly valued for medicinal purposes. MATERIALS AND METHODS: Seeds at a moisture content of 6% were immersed in liquid nitrogen (LN) before warming and recovery. Plantlet establishment and growth were assessed over a period of 70 days and anthraquinone synthesis was determined in roots, stems and leaves. RESULTS: The results showed an initial lag in the germination rate of cryopreserved seeds compared with control seeds; however, this difference disappeared over time. The lag in seedling emergence observed in cryostored seeds was also evident in the plant characteristics measured following 30 days of culture when all plant parameters measured were significantly higher in plants produced from control than cryostored seeds. However, after 70 days of growth, these differences were no longer apparent. Anthraquinone levels were also initially lower (at 30 days) in plants regenerated from cryopreserved seeds than those from control seeds, however, this difference was substantially reduced by 70 days thereby indicating the ability of these plants to accumulate secondary metabolites, albeit at a reduced rate, during the early stages of development. CONCLUSION: In S. mahagoni, the delay in anthraquinone production in plants regenerated from cryostored seeds during the early stages of development may have occurred as a consequence of the preferential allocation of resources towards the initiation of recovery processes in response to the stresses imposed by cryopreservation. Once the stresses were overcome and plant growth resumed, resources could be directed to secondary processes such as anthraquinone synthesis. doi.org/10.54680/fr22610110412.


Assuntos
Criopreservação , Meliaceae , Criopreservação/métodos , Sementes/fisiologia , Plântula , Germinação/fisiologia , Plantas
2.
Cryo Letters ; 43(1): 58-65, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35315871

RESUMO

BACKGROUND: Trees within the Calophyllum genus are multi-use trees that produce valuable wood, phytochemicals with a range of biological activities, and seed oil as a source of biodiesel. As a consequence of climate change, there is a need to develop strategies to preserve valuable plant genetic resources. Cryopreservation represents the most suitable option for the long-term storage of germplasm with minimal space and maintenance requirements. OBJECTIVE: To determine appropriate methods to cryopreserve seeds of Calophyllum antillanum and maintain secondary compound production. MATERIALS AND METHODS: Seeds at a moisture content of 6% were used to evaluate two treatments: seeds immersed in liquid nitrogen and control seeds. Biosynthetic pathway efficiency was assessed post-cryo by determining anthraquinone contents in roots, stems and leaves following 30 and 75 d of seedling growth. RESULTS: The results indicated that exposure to liquid nitrogen delayed germination and seedling emergence for a period of up to 45 d after seed sowing. By 60 d of cultivation, no significant differences in plant growth were observed for cryostored and control seeds. The levels of anthraquinones, which were also measured in seeds and seedlings, were lower in plants regenerated from cryostored seeds following 30 d of growth, but there were no differences in roots and stems by 75 d of growth. Furthermore, the difference in leaf anthraquinone levels for cryopreserved and control seeds at 75 d was much smaller than at 30 d. CONCLUSION: The low initial anthraquinone levels in emerging seedlings correlated with the initial slow growth of cryopreserved seeds.


Assuntos
Calophyllum , Plântula , Antraquinonas/farmacologia , Criopreservação/métodos , Nitrogênio/química , Folhas de Planta , Sementes
3.
Br J Dermatol ; 183(1): 71-77, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32348545

RESUMO

BACKGROUND: The cutaneous manifestations of COVID-19 disease are poorly characterized. OBJECTIVES: To describe the cutaneous manifestations of COVID-19 disease and to relate them to other clinical findings. METHODS: We carried out a nationwide case collection survey of images and clinical data. Using a consensus we described five clinical patterns. We later described the association of these patterns with patient demographics, the timing in relation to symptoms of the disease, the severity and the prognosis. RESULTS: The lesions may be classified as acral areas of erythema with vesicles or pustules (pseudo-chilblain) (19%), other vesicular eruptions (9%), urticarial lesions (19%), maculopapular eruptions (47%) and livedo or necrosis (6%). Vesicular eruptions appear early in the course of the disease (15% before other symptoms). The pseudo-chilblain pattern frequently appears late in the evolution of the COVID-19 disease (59% after other symptoms), while the rest tend to appear with other symptoms of COVID-19. The severity of COVID-19 shows a gradient from less severe disease in acral lesions to more severe in the latter groups. The results are similar for confirmed and suspected cases, in terms of both clinical and epidemiological findings. Alternative diagnoses are discussed but seem unlikely for the most specific patterns (pseudo-chilblain and vesicular). CONCLUSIONS: We provide a description of the cutaneous manifestations associated with COVID-19 infection. These may help clinicians approach patients with the disease and recognize cases presenting with few symptoms. What is already known about this topic? Previous descriptions of cutaneous manifestations of COVID-19 were case reports and mostly lacked illustrations. What does this study add? We describe a large, representative sample of patients with unexplained skin manifestations and a diagnosis of COVID-19, using a consensus method to define morphological patterns associated with COVID-19. We describe five clinical patterns associated with different patient demographics, timing and prognosis, and provide illustrations of these patterns to allow for easy recognition.


Assuntos
Betacoronavirus/patogenicidade , Consenso , Infecções por Coronavirus/complicações , Pneumonia Viral/complicações , Dermatopatias Virais/classificação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , COVID-19 , Criança , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/virologia , Dermatologistas/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/diagnóstico , Pneumonia Viral/epidemiologia , Pneumonia Viral/virologia , Prognóstico , Estudos Prospectivos , SARS-CoV-2 , Dermatopatias Virais/diagnóstico , Dermatopatias Virais/virologia , Espanha/epidemiologia , Inquéritos e Questionários/estatística & dados numéricos , Terminologia como Assunto , Fatores de Tempo , Adulto Jovem
4.
Clin Exp Immunol ; 191(2): 180-188, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28960271

RESUMO

Innate lymphocyte populations, such as innate lymphoid cells (ILCs), γδ T cells, invariant natural killer T (iNK T) cells and mucosal-associated invariant T (MAIT) cells are emerging as important effectors of innate immunity and are involved in various inflammatory and autoimmune diseases. The aim of this study was to assess the frequencies and absolute numbers of innate lymphocytes as well as conventional lymphocytes and monocytes in peripheral blood from a cohort of anti-neutrophil cytoplasm autoantibody (ANCA)-associated vasculitis (AAV) patients. Thirty-eight AAV patients and 24 healthy and disease controls were included in the study. Patients with AAV were sampled both with and without immunosuppressive treatment, and in the setting of both active disease and remission. The frequencies of MAIT and ILC2 cells were significantly lower in patients with AAV and in the disease control group compared to healthy controls. These reductions in the AAV patients remained during remission. B cell count and frequencies were significantly lower in AAV in remission compared to patients with active disease and disease controls. Despite the strong T helper type 2 (Th) preponderance of eosinophilic granulomatosis with polyangiitis, we did not observe increased ILC2 frequency in this cohort of patients. The frequencies of other cell types were similar in all groups studied. Reductions in circulating ILC2 and MAIT cells reported previously in patients with AAV are not specific for AAV, but are more likely to be due to non-specific manifestations of renal impairment and chronic illness. Reduction in B cell numbers in AAV patients experiencing remission is probably therapy-related.


Assuntos
Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/imunologia , Linfócitos B/imunologia , Rim/patologia , Subpopulações de Linfócitos/imunologia , Células T Invariantes Associadas à Mucosa/imunologia , Células T Matadoras Naturais/imunologia , Linfócitos T/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/tratamento farmacológico , Estudos de Coortes , Feminino , Humanos , Imunidade Inata , Terapia de Imunossupressão , Contagem de Linfócitos , Masculino , Microcirculação , Pessoa de Meia-Idade , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo
7.
Mycorrhiza ; 24 Suppl 1: S47-54, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24469788

RESUMO

Successful cultivation of black truffle (Tuber melanosporum) requires a long-term investment and the maintenance of the symbiosis throughout its preproductive and productive years. Monitoring the symbiosis over time is challenging, as it requires methods that can detect the belowground proliferation of the fungus associated with its host tree. In this study, we used a chronosequence design to study the expansion pattern of this fungus as the host tree grows. We hypothesize that this expansion can be estimated by monitoring T. melanosporum DNA from soil beneath host trees of different ages (3, 5, 7, 10, 14, and 20 years old) and at different distances from the trunk of the trees (40, 100, and 200 cm). We also wished to evaluate the presences of Tuber brumale and Tuber indicum, potentially problematic truffle species, in these plantations. To detect the mycelium of T. melanosporum in these soils, we extracted DNA and performed polymerase chain reaction (PCR) with Tuber species-specific primers, and to estimate DNA amount, we measured relative band intensities from the amplicons in agarose gels. Both age and distance were related to T. melanosporum DNA quantity, which was more abundant in the oldest age classes, reaching a plateau in 5-7 years. At 40 cm from the tree, there were no differences in T. melanosporum DNA amounts in orchards of different ages, but at 100 and 200 cm, younger orchards had less T. melanosporum DNA. We did not detect DNA from T. brumale or T. indicum in any of our samples.


Assuntos
Ascomicetos/fisiologia , Micélio/crescimento & desenvolvimento , Micorrizas/fisiologia , Quercus/microbiologia , Agricultura , Ascomicetos/genética , Ascomicetos/crescimento & desenvolvimento , DNA Fúngico/análise , Carpóforos/genética , Carpóforos/crescimento & desenvolvimento , Carpóforos/fisiologia , Micorrizas/genética , Micorrizas/crescimento & desenvolvimento , Microbiologia do Solo , Fatores de Tempo
8.
Rev Gastroenterol Mex (Engl Ed) ; 89(1): 80-88, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-36890062

RESUMO

INTRODUCTION: The treatment and diagnosis of chronic diarrhea in the immunocompromised patient depends on the ability to rapidly detect the etiologic agents. AIMS: Our aim was to evaluate the results of the FilmArray® gastrointestinal panel in patients newly diagnosed with HIV infection that presented with chronic diarrhea. MATERIAL AND METHODS: Utilizing nonprobability consecutive convenience sampling, 24 patients were included that underwent molecular testing for the simultaneous detection of 22 pathogens. RESULTS: In 24 HIV-infected patients with chronic diarrhea, enteropathogen bacteria were detected in 69% of the cases, parasites in 18%, and viruses in 13%. Enteropathogenic Escherichia coli and enteroaggregative Escherichia coli were the main bacteria identified, Giardia lamblia was found in 25%, and norovirus was the most frequent viral agent. The median number of infectious agents per patient was three (range of 0 to 7). The biologic agents not identified through the FilmArray® method were tuberculosis and fungi. CONCLUSIONS: Several infectious agents were simultaneously detected through the FilmArray® gastrointestinal panel in patients with HIV infection and chronic diarrhea.

9.
Molecules ; 17(1): 480-91, 2012 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-22222907

RESUMO

The permeation properties of twenty newly synthesized α-alkoxyalkanoyl and α-aryloxyalkanoyl C-21 esters of standard corticosteroids: Fluocinolone acetonide, dexamethasone, triamcinolone acetonide and hydrocortisone were established using a PAMPA assay (70% silicone oil and 30% isopropyl myristate). The data were compared with parent corticosteroids with addition of mometasone furoate and hydrocortisone acetate. All newly synthesized corticosteroid C-21 esters have effective permeability coefficients higher then -6, mostly followed with high values of retention factors and low permeation. The examined compounds were grouped through relationship between obtained retention factors and permeation parameters (groups I-III). The classification confirmed group I (membrane retentions as well as permeation lower then 30%) for all corticosteroid standards except mometasone furoate, a potent topical corticosteroid which, with high membrane retention (81%) and low permeation (7.7%) fits into group III. The largest number of new synthesized corticosteroids C-21 esters, among them all fluocinolone acetonide C-21 esters, have high membrane retentions (32.4%-86.5%) and low permeations (1.3%-27.1%), fitting in group III. The classification was related to previously obtained anti-inflammatory activity data for the fluocinolone acetonide C-21 esters series. According to the PAMPA results the new synthesized esters could be considered as potential new prodrugs with useful benefit/risk ratio.


Assuntos
Ésteres/química , Membranas Artificiais , Modelos Biológicos , Pregnanos/química , Pró-Fármacos/química , Ésteres/síntese química , Ésteres/normas , Humanos , Miristatos/química , Permeabilidade , Pregnanos/síntese química , Pregnanos/normas , Pró-Fármacos/síntese química , Pró-Fármacos/normas , Padrões de Referência , Óleos de Silicone/química , Absorção Cutânea
10.
Molecules ; 16(3): 2658-71, 2011 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-21441868

RESUMO

In this study the solvolysis of newly synthesized fluocinolone acetonide C-21 esters was analysed in comparison with fluocinonide during a 24-hour period of time. The solvolysis was performed in an ethanol-water (90:10 v/v) mixture using the excess of NaHCO3. The solvolytic mixtures of each investigated ester have been assayed by a RP-HPLC method using isocratic elution with methanol-water (75:25 v/v); flow rate 1 mL/min; detection at 238 nm; temperature 25 °C. Solvolytic rate constants were calculated from the obtained data. Geometry optimizations and charges calculations were carried out by Gaussian W03 software. A good correlation (R = 0.9924) was obtained between solvolytic rate constants and the polarity of the C-O2 bond of those esters. The established relation between solvolytic rate constant (K) and lipophilicity (cLogP) with experimental anti-inflammatory activity could be indicative for topical corticosteroid prodrug activation.


Assuntos
Fluocinolona Acetonida/química , Pró-Fármacos/farmacocinética , Ésteres , Cinética , Solventes
11.
Rev Esp Anestesiol Reanim ; 57(6): 377-80, 2010.
Artigo em Espanhol | MEDLINE | ID: mdl-20645490

RESUMO

We describe the detection of postoperative neurologic complications by means of monitoring cerebral oximetry during cardiac surgery. A 54-year-old man underwent emergency surgery for aortic dissection, type A. Cerebral oximetry was monitored by near-infrared spectroscopy. At the start of total cardiopulmonary bypass through the axillary artery, cerebral oxygen saturation fell more than 50% from baseline in both hemispheres. Saturation did not improve on optimizing factors that influence cerebral blood flow. Improvement came only when the recently inserted arterial cannula was switched to the ascending aortic prosthetic graft. After surgery, the patient was diagnosed with anoxic brain injury. We believe that the detected fall in cerebral oxygen saturation during axillary artery cannulization probably coincided with the occurrence of anoxic brain injury.


Assuntos
Circulação Cerebrovascular , Hipóxia-Isquemia Encefálica/diagnóstico , Complicações Intraoperatórias/diagnóstico , Monitorização Intraoperatória/métodos , Oximetria/métodos , Estado Vegetativo Persistente/etiologia , Complicações Pós-Operatórias/etiologia , Espectroscopia de Luz Próxima ao Infravermelho , Dissecção Aórtica/cirurgia , Aorta/cirurgia , Aneurisma Aórtico/cirurgia , Valva Aórtica/cirurgia , Artéria Axilar , Implante de Prótese Vascular , Ponte Cardiopulmonar , Cateteres de Demora , Circulação Extracorpórea/efeitos adversos , Implante de Prótese de Valva Cardíaca , Humanos , Hipotermia Induzida , Hipóxia-Isquemia Encefálica/etiologia , Hipóxia-Isquemia Encefálica/terapia , Complicações Intraoperatórias/etiologia , Complicações Intraoperatórias/terapia , Masculino , Pessoa de Meia-Idade
12.
J Cell Biol ; 114(1): 155-67, 1991 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2050740

RESUMO

Sphingosine, a metabolite of membrane sphingolipids, regulates proliferation of quiescent Swiss 3T3 fibroblasts (Zhang, H., N. E. Buckley, K. Gibson. and S. Spiegel. 1990. J. Biol. Chem. 265:76-81). The present study provides new insights into the formation and function of a unique phospholipid, a metabolite of sphingosine, which was unequivocally identified as sphingosine-1-phosphate. The rapid increase in 32P-labeled sphingosine-1-phosphate levels induced by sphingosine was concentration dependent and correlated with its effect on DNA synthesis. Similar to the mitogenic effects of sphingosine, low concentrations of sphingosine-1-phosphate stimulated DNA synthesis and induced pronounced morphological alterations. Both sphingosine and sphingosine-1-phosphate stimulated DNA synthesis in cells made protein kinase C deficient by prolonged treatment with phorbol ester and sphingosine still elicited similar increases in sphingosine-1-phosphate levels in these cells. Although both sphingosine and sphingosine-1-phosphate acted synergistically with a wide variety of growth factors, there was no additive or synergistic effect in response to a combination of sphingosine and sphingosine-1-phosphate. Using a digital imaging system for measurement of calcium changes, we observed that both sphingosine and sphingosine-1-phosphate are potent calcium-mobilizing agonists in viable 3T3 fibroblasts. The rapid rise in cytosolic free calcium was independent of the presence of calcium in the external medium, indicating that the response is due to the mobilization of calcium from internal store. Our results suggest that sphingosine-1-phosphate may be a component of the intracellular second messenger system that is involved in calcium release and the regulation of cell growth induced by sphingosine.


Assuntos
Cálcio/metabolismo , Divisão Celular , DNA/biossíntese , Lisofosfolipídeos , Esfingosina/análogos & derivados , Animais , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Regulação para Baixo , Substâncias de Crescimento/farmacologia , Proteína Quinase C/metabolismo , Sistemas do Segundo Mensageiro , Esfingosina/metabolismo , Esfingosina/farmacologia
13.
J Cell Biol ; 147(3): 545-58, 1999 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-10545499

RESUMO

Sphingosine-1-phosphate (SPP) is a bioactive lipid that has recently been identified as the ligand for the EDG family of G protein-coupled cell surface receptors. However, the mitogenic and survival effects of exogenous SPP may not correlate with binding to cell-surface receptors (Van Brocklyn, J.R., M.J. Lee, R. Menzeleev, A. Olivera, L. Edsall, O. Cuvillier, D.M. Thomas, P.J.P. Coopman, S. Thangada, T. Hla, and S. Spiegel. 1998. J. Cell Biol. 142:229-240). The recent cloning of sphingosine kinase, a unique lipid kinase responsible for the formation of SPP, has provided a new tool to investigate the role of intracellular SPP. Expression of sphingosine kinase markedly increased SPP levels in NIH 3T3 fibroblasts and HEK293 cells, but no detectable secretion of SPP into the medium was observed. The increased sphingosine kinase activity in NIH 3T3 fibroblasts was sufficient to promote growth in low- serum media, expedite the G(1)/S transition, and increase DNA synthesis and the proportion of cells in the S phase of the cell cycle with a concomitant increase in cell numbers. Transient or stable overexpression of sphingosine kinase in NIH 3T3 fibroblasts or HEK293 cells protected against apoptosis induced by serum deprivation or ceramide elevation. N,N-Dimethylsphingosine, a competitive inhibitor of sphingosine kinase, blocked the effects of sphingosine kinase overexpression on cell proliferation and suppression of apoptosis. In contrast, pertussis toxin did not abrogate these biological responses. In Jurkat T cells, overexpression of sphingosine kinase also suppressed serum deprivation- and ceramide-induced apoptosis and, to a lesser extent, Fas-induced apoptosis, which correlated with inhibition of DEVDase activity, as well as inhibition of the executionary caspase-3. Taken together with ample evidence showing that growth and survival factors activate sphingosine kinase, our results indicate that SPP functions as a second messenger important for growth and survival of cells. Hence, SPP belongs to a novel class of lipid mediators that can function inside and outside cells.


Assuntos
Divisão Celular , Sobrevivência Celular , Lisofosfolipídeos , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Receptores Acoplados a Proteínas G , Sistemas do Segundo Mensageiro , Esfingosina/análogos & derivados , Animais , Apoptose/efeitos dos fármacos , Caspase 3 , Inibidores de Caspase , Caspases/metabolismo , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Citosol/metabolismo , DNA/biossíntese , Ativação Enzimática/efeitos dos fármacos , Humanos , Camundongos , Peptídeo Hidrolases/metabolismo , Toxina Pertussis , Fosfotransferases (Aceptor do Grupo Álcool)/antagonistas & inibidores , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Fator de Crescimento Derivado de Plaquetas/farmacologia , Receptores de Superfície Celular/antagonistas & inibidores , Receptores de Superfície Celular/metabolismo , Receptores de Lisofosfolipídeos , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Sistemas do Segundo Mensageiro/efeitos dos fármacos , Esfingosina/antagonistas & inibidores , Esfingosina/genética , Esfingosina/metabolismo , Esfingosina/farmacologia , Transfecção , Fatores de Virulência de Bordetella/farmacologia , Receptor fas/metabolismo
14.
J Cell Biol ; 121(6): 1385-95, 1993 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8389770

RESUMO

Sphingosylphosphorylcholine (SPC), or lysophingomyelin, a wide-spectrum growth promoting agent for a variety of cell types (Desai, N. N., and S. Spiegel. 1991. Biochem. Biophys. Res. Comm. 181: 361-366), stimulates cellular proliferation of quiescent Swiss 3T3 fibroblasts to a greater extent than other known growth factors or than the structurally related molecules, sphingosine and sphingosine-1-phosphate. SPC potentiated the mitogenic effect of an activator of protein kinase C, 12-O-tetradecanoylphorbol 13-acetate, and did not compete with phorbol esters for binding to protein kinase C in intact Swiss 3T3 fibroblasts. However, downregulation of protein kinase C, by prolonged treatment with phorbol ester, reduced, but did not eliminate, the ability of SPC to stimulate DNA synthesis, indicating that SPC may act via both protein kinase C-dependent and -independent signaling pathways. SPC induced a rapid rise in intracellular free calcium ([Ca2+]i) in viable 3T3 fibroblasts determined with a digital imaging system. Although the increases in [Ca2+]i were observed even in the absence of calcium in the external medium, no increase in the levels of inositol phosphates could be detected in response to mitogenic concentrations of SPC. Furthermore, in contrast to sphingosine or sphingosine-1-phosphate, the mitogenic effect of SPC was not accompanied by increases in phosphatidic acid levels or changes in cAMP levels. SPC, but not sphingosine or sphingosine-1-phosphate, stimulates the release of arachidonic acid. Therefore, the ability of SPC to act an extremely potent mitogen may be due to activation of signaling pathway(s) distinct from those used by sphingosine or sphingosine-1-phosphate.


Assuntos
Substâncias de Crescimento/fisiologia , Lisofosfolipídeos , Fosforilcolina/análogos & derivados , Esfingosina/análogos & derivados , Células 3T3 , Animais , Ácido Araquidônico/metabolismo , Cálcio/metabolismo , Divisão Celular/fisiologia , AMP Cíclico/metabolismo , Camundongos , Fosfatidilinositóis/metabolismo , Fosforilcolina/metabolismo , Proteína Quinase C/fisiologia , Transdução de Sinais/fisiologia , Esfingosina/metabolismo
15.
J Cell Biol ; 142(1): 229-40, 1998 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-9660876

RESUMO

Sphingosine-1-phosphate (SPP), a bioactive lipid, acts both intracellularly and extracellularly to cause pleiotropic biological responses. Recently, we identified SPP as a ligand for the G protein-coupled receptor Edg-1 (Lee, M.-J., J.R. Van Brocklyn, S. Thangada, C.H. Liu, A.R. Hand, R. Menzeleev, S. Spiegel, and T. Hla. 1998. Science. 279:1552-1555). Edg-1 binds SPP with remarkable specificity as only sphinganine-1-phosphate displaced radiolabeled SPP, while other sphingolipids did not. Binding of SPP to Edg-1 resulted in inhibition of forskolin-stimulated cAMP accumulation, in a pertussis toxin-sensitive manner. In contrast, two well-characterized biological responses of SPP, mitogenesis and prevention of apoptosis, were clearly unrelated to binding to Edg-1 and correlated with intracellular uptake. SPP also stimulated signal transduction pathways, including calcium mobilization, activation of phospholipase D, and tyrosine phosphorylation of p125(FAK), independently of edg-1 expression. Moreover, DNA synthesis in Swiss 3T3 fibroblasts was significantly and specifically increased by microinjection of SPP. Finally, SPP suppresses apoptosis of HL-60 and pheochromocytoma PC12 cells, which do not have specific SPP binding or expression of Edg-1 mRNA. Conversely, sphinganine-1-phosphate, which binds to and signals via Edg-1, does not have any significant cytoprotective effect. Thus, SPP is a prototype for a novel class of lipid mediators that act both extracellularly as ligands for cell surface receptors and intracellularly as second messengers.


Assuntos
Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/metabolismo , Proteínas Imediatamente Precoces/metabolismo , Lisofosfolipídeos , Receptores de Superfície Celular/metabolismo , Receptores Acoplados a Proteínas G , Esfingosina/análogos & derivados , Células 3T3 , Animais , Divisão Celular , Linhagem Celular , Sobrevivência Celular , AMP Cíclico/metabolismo , Células HL-60 , Humanos , Proteínas Imediatamente Precoces/genética , Camundongos , Células PC12 , Ratos , Receptores de Lisofosfolipídeos , Transdução de Sinais , Esfingosina/metabolismo , Esfingosina/fisiologia
16.
Science ; 291(5509): 1800-3, 2001 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-11230698

RESUMO

EDG-1 is a heterotrimeric guanine nucleotide binding protein-coupled receptor (GPCR) for sphingosine-1-phosphate (SPP). Cell migration toward platelet-derived growth factor (PDGF), which stimulates sphingosine kinase and increases intracellular SPP, was dependent on expression of EDG-1. Deletion of edg-1 or inhibition of sphingosine kinase suppressed chemotaxis toward PDGF and also activation of the small guanosine triphosphatase Rac, which is essential for protrusion of lamellipodia and forward movement. Moreover, PDGF activated EDG-1, as measured by translocation of beta-arrestin and phosphorylation of EDG-1. Our results reveal a role for receptor cross-communication in which activation of a GPCR by a receptor tyrosine kinase is critical for cell motility.


Assuntos
Quimiotaxia , Proteínas Imediatamente Precoces/metabolismo , Lisofosfolipídeos , Fator de Crescimento Derivado de Plaquetas/farmacologia , Receptores de Superfície Celular , Receptores Acoplados a Proteínas G , Esfingosina/análogos & derivados , Esfingosina/metabolismo , Animais , Arrestinas/metabolismo , Becaplermina , Linhagem Celular , Membrana Celular/metabolismo , Células Cultivadas , Quimiotaxia/efeitos dos fármacos , Deleção de Genes , Humanos , Proteínas Imediatamente Precoces/genética , Camundongos , Músculo Liso Vascular/citologia , Músculo Liso Vascular/metabolismo , Fosforilação , Fosfotransferases (Aceptor do Grupo Álcool)/antagonistas & inibidores , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Fator de Crescimento Derivado de Plaquetas/metabolismo , Proteínas Proto-Oncogênicas c-sis , Receptor Cross-Talk , Receptores de Lisofosfolipídeos , Receptores do Fator de Crescimento Derivado de Plaquetas/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Transdução de Sinais , Esfingosina/farmacologia , Transfecção , beta-Arrestinas
17.
Mol Biol Cell ; 17(1): 327-35, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16280360

RESUMO

In this study, we investigated the role of phospholipase D (PLD) in mediating Arf6 function in cells. Expression of Arf6 mutants that are defective in activating PLD, Arf6N48R and Arf6N48I, inhibited membrane recycling to the plasma membrane (PM), resulting in an accumulation of tubular endosomal membranes. Additionally, unlike wild-type Arf6, neither Arf6 mutant could generate protrusions or recruit the Arf6 GTPase activating protein (GAP) ACAP1 onto the endosome in the presence of aluminum fluoride. Remarkably, all of these phenotypes, including accumulated tubular endosomes, blocked recycling, and failure to make protrusions and recruit ACAP effectively, could be recreated in either untransfected cells or cells expressing wild-type Arf6 by treatment with 1-butanol to inhibit the formation of phosphatidic acid (PA), the product of PLD. Moreover, most of the defects present in cells expressing Arf6N48R or N48I could be reversed by treatment with agents expected to elevate PA levels in cells. Together, these observations provide compelling evidence that Arf6 stimulation of PLD is required for endosomal membrane recycling and GAP recruitment.


Assuntos
Fatores de Ribosilação do ADP/química , Fatores de Ribosilação do ADP/metabolismo , Endossomos/metabolismo , Membranas Intracelulares/metabolismo , Mutação/genética , Fosfolipase D/metabolismo , Fator 6 de Ribosilação do ADP , Fatores de Ribosilação do ADP/genética , Compostos de Alumínio/farmacologia , Asparagina/genética , Asparagina/metabolismo , Ativação Enzimática/efeitos dos fármacos , Fluoretos/farmacologia , Proteínas Ativadoras de GTPase/metabolismo , Células HeLa , Humanos , Fenótipo
18.
J Healthc Qual Res ; 34(2): 59-65, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30713136

RESUMO

BACKGROUND: Healthcare accreditation seeks to promote the organisational change in healthcare organisations from an approach that values the level of progress achieved through a validated reference framework. The aim of this paper is to analyse the role played by accreditation through the experience perceived by health professionals during the process of self-assessment and external evaluation, taking into account three dimensions of analysis: focus on the patient, internal organisation and leadership, and impact on the clinical aspects of healthcare. MATERIAL AND METHODS: Design: Semi-structured interviews with key informants from clinical management units (CMU) within the Andalusian Health System (Spain). PARTICIPANTS: The key informants in each CMU were the clinical leader, the head of nursing and two health professionals (doctors and nurses). A qualitative research protocol was employed to conduct the semi-structured interviews (n=52 interviews) with physicians and nurses, in order to analyse their experience with the accreditation process. RESULTS: The analysis identified four main outcomes related to the accreditation process perceived by professionals: (1) A benchmarking conceptualisation of the process; (2) Improvements in patient-centred care, quality of clinical records, and organisational culture of the units; (3) Improvement of patient safety culture; (4) As negative outcomes, a slight perception of bureaucratisation and standardisation of the clinical practice. CONCLUSIONS: The described initiative of accreditation process in Andalusia (Spain) is widely perceived as positive by health professionals since it fosters the organisational change, although it also has a slightly negative bureaucratisation effect on clinical practice.


Assuntos
Acreditação/normas , Atitude do Pessoal de Saúde , Atenção à Saúde/organização & administração , Atenção à Saúde/normas , Inovação Organizacional , Humanos , Espanha
19.
Tissue Cell ; 39(4): 267-75, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17675200

RESUMO

Oligoryzomys flavescens, a common rodent of the temperate regions of South America, has been identified as a Hantavirus reservoir. There is still little information concerning its reproductive biology, which is essential to devise effective control measurement of natural populations. This rodent is a seasonal breeder and adult males exhibit a short period of testicular regression during winter months (June-August). In the present study we provided a histological and ultrastructural analysis of the composition of the testis of sexually mature O. flavescens during the breeding season. Over 95% of the testicular parenchyma was occupied by the seminiferous tubules and less than 5% by the interstitial tissue. The mean tubular diameter and epithelium height were 147.2 and 57.8 microm, respectively. The spermatogenic wave was characterized and eight spermatogenesis stages were identified according to the tubular morphology method. Their length, estimated as their relative frequencies, were (I-VIII) 8.8, 14.9, 4.0, 5.0, 10.4, 5.8, 27.0, and 23.9. Ultrastructural features of spermiogenesis are shown for the first time in a sigmodontine rodent.


Assuntos
Reservatórios de Doenças , Orthohantavírus/fisiologia , Túbulos Seminíferos/citologia , Sigmodontinae/anatomia & histologia , Sigmodontinae/virologia , Testículo/citologia , Animais , Células Intersticiais do Testículo/citologia , Masculino , Camundongos , Microscopia Eletrônica de Transmissão , Estações do Ano , Epitélio Seminífero/citologia , Sigmodontinae/classificação , América do Sul , Espermátides/citologia , Espermatócitos/citologia , Espermatogênese , Espermatozoides/citologia , Fatores de Tempo
20.
Acta otorrinolaringol. cir. cuello (En línea) ; 50(2): 151-158, 20220000. ilus, tab
Artigo em Espanhol | LILACS, COLNAL | ID: biblio-1382352

RESUMO

Introducción: la mediastinitis se define como el proceso inflamatorio usualmente infeccioso del tejido conectivo mediastinal y los órganos que este rodea. Específicamente, la mediastinitis descendente corresponde a una complicación rara por infección de los espacios profundos del cuello, la orofaringe o la cavidad oral, que se extiende a través de los espacios fasciales del cuello y los diseca. De forma infrecuente, esta patología puede originarse a partir de la parotiditis, las infecciones de la piel del cuello o la epiglotitis. También, de manera menos frecuente, puede generarse en el contexto de un traumatismo del cuello o la cavidad oral. En este estudio se pretende llamar la atención, en particular, sobre los aspectos que involucran al especialista otorrinolaringólogo en el manejo de los pacientes con infecciones profundas del cuello y su rol en el diagnóstico y tratamiento eficaz de la mediastinitis descendente, como la principal causa de mortalidad en estos casos. Metodología: se llevó a cabo una búsqueda con las palabras clave "Airway" "Ludwig's angina" en PubMed, no se efectuó filtración por fecha ni tipo de estudio. Se encontró un total de 147 artículos. Se realizó lectura de los resúmenes por los autores y se seleccionaron 50. Se realizó lectura crítica del texto completo de los 50 artículos resultantes de la búsqueda y se extrajo la información relevante. Conclusión: esta patología de marcada severidad conlleva a un aumento significativo de la mortalidad. Su tratamiento, aunque permanece controversial en ciertas circunstancias, debe ser agresivo y oportuno, con un enfoque en el rol del otorrinolaringólogo en 4 pilares de tratamiento: el drenaje quirúrgico, la antibioticoterapia de amplio espectro, el soporte hemodinámico y la seguridad de la vía aérea.


Introduction: Mediastinitis is defined as the usually infectious inflammatory process of the mediastinal connective tissue and the organs it surrounds. Specifically, descending mediastinitis corresponds to a rare complication, an infection of deep spaces of the neck, oropharynx, or oral cavity, which extends through the facial spaces of the neck, dissecting. Less frequent, this pathology can originate from parotiditis, skin infections of the neck or epiglottitis. Also, less frequent it can be generated in the context of trauma to the neck or oral cavity. This study intends to draw attention to the aspects that involve the ENT specialist in the management of patients with deep neck infections and their role in the diagnosis and effective treatment of descending mediastinitis as the main cause of mortality in these patients. Methodology: A search was carried out with the keywords "Airway" "Ludwig's angina" in PubMed, no filtering was performed by date or type of study, finding a total of 147 articles, abstracts were read by the authors, selecting 50. A critical reading of the 50 articles full texts is carried out and the relevant information is extracted. Conclusion: This pathology of marked severity, carries a significant increase in mortality and its treatment, although it remains controversial in certain circumstances, it must be aggressive and timely, focusing the role of the otorhinolaryngologist on 4 pillars of treatment: surgical drainage, antibiotic therapy, hemodynamic support, and airway safety.


Assuntos
Humanos , Angina de Ludwig , Remodelação das Vias Aéreas , Mediastinite
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