RESUMO
Summary: Objectives. To describe the prevalence of allergic sensitization to Storage Dust Mites (SDM), access whether the place of living and occupational exposure were determinants for SDM sensitization and study association between Lepidoglyphus destructor and other SDM sensitization. Methods. Prospective analysis of patients evaluated for suspected allergic rhinitis and/or asthma that performed Skin Prick Tests (SPT) to SDM between January and December 2018 in our Department. Results. Two hundred consecutive patients were evaluated for rhinitis and/or asthma in our outpatient consultation: 123 (61.5%) presented positivity for at least one SDM, 68.3% were female and the mean age was 33.1 ± 12.12. Lepidoglyphus destructor (69.9%) was the most prevalent, followed by Tyrophagus putrescentiae (50.4%), Blomia tropicalis and Glycyphagus domesticus (48.8%) and Acarus siro (24.4%). Living in a rural place was not associated with a higher prevalence of sensitization to SDM, except for Acarus siro (p = 0.032), and working in a place with storage areas was not associated with sensitization to any of SDM. Sensitization to Lepidoglyphus destructor was associated with sensitization to Blomia tropicalis, Glycyphagus domesticus and Tyrophagus putrescentiae (p less than 0.005), but not with Acarus siro.Conclusions. Our study suggests that our population, independently of their occupational exposure and place of residency, are sensitized to SDM and that evaluation of sensitization to SDM should be considered as standard practice.
Assuntos
Acaridae , Asma , Ácaros , Adulto , Alérgenos , Animais , Asma/epidemiologia , Poeira , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Pyroglyphidae , Testes Cutâneos , Adulto JovemAssuntos
Asma/diagnóstico , Aplicativos Móveis/normas , Rinite Alérgica/diagnóstico , Inquéritos e Questionários/normas , Adolescente , Telefone Celular , Feminino , Humanos , Masculino , Avaliação de Resultados em Cuidados de Saúde , Medidas de Resultados Relatados pelo Paciente , Telemedicina , Adulto JovemRESUMO
The McGrath video laryngoscope is a new airway management device. It is similar to the Macintosh laryngoscope but incorporates a blade at a 60 degrees angle and a camera that sends an image to a color display screen connected to the handle. The device, which requires use of an anti-fog substance and an introducer to guide the angled blade, has been reported to aid in the management of difficult airways. We present 3 cases of difficult oral-tracheal intubation managed with the McGrath video laryngoscope and a Frova intubating introducer. Advantages of this introducer are that it offers the possibility of administering oxygen or changing the size of the endotracheal tube if the first choice proves inappropriate. We discuss whether or not tests to predict difficult airways are applicable when the McGrath video laryngoscope is being used, given that it is not necessary to align the axes of the 3 airways. We conclude it may be useful to combine the McGrath video laryngoscope and the Frova introducer to manage difficult airways.
Assuntos
Obstrução das Vias Respiratórias , Intubação Intratraqueal/métodos , Laringoscópios , Gravação em Vídeo/instrumentação , Parede Abdominal/cirurgia , Vértebras Cervicais/cirurgia , Comorbidade , Discotomia , Desenho de Equipamento , Feminino , Humanos , Intubação Intratraqueal/instrumentação , Masculino , Pessoa de Meia-Idade , Oxigenoterapia/instrumentação , Nódulo da Glândula Tireoide/cirurgia , TireoidectomiaRESUMO
BACKGROUND: Advances in osteoporosis (OP)case definition, treatment options, optimal therapy duration and pharmacoeconomic evidence in the national context motivated the Portuguese Society of Rheumatology (SPR) to update the Portuguese recommendations for the diagnosis and management of osteoporosis published in 2007. METHODS: SPR bone diseases' working group organized meetings involving 55 participants (rheumatologists, rheumatology fellows and one OP specialist nurse) to debate and develop the document. First, the working group selected 11 pertinent clinical questions for the diagnosis and management of osteoporosis in standard clinical practice. Then, each question was investigated through literature review and draft recommendations were built through consensus. When insufficient evidence was available, recommendations were based on experts' opinion and on good clinical practice. At two national meetings, the recommendations were discussed and updated. A draft of the recommendations full text was submitted to critical review among the working group and suggestions were incorporated. A final version was circulated among all Portuguese rheumatologists before publication and the level of agreement was anonymously assessed using an online survey. RESULTS: The 2018 SPR recommendations provide comprehensive guidance on osteoporosis prevention, diagnosis, fracture risk assessment, pharmacological treatment initiation, therapy options and duration of treatment, based on the best available evidence. They attained desirable agreement among Portuguese rheumatologists. As more evidence becomes available, periodic revisions will be performed. Target audience and patient population: The target audience for these guidelines includes all clinicians. The target patient population includes adult Portuguese people. Intended use: These recommendations provide general guidance for typical cases. They may not be appropriate in all situations - clinicians are encouraged to consider this information together with updated evidence and their best clinical judgment in individual cases.
Assuntos
Osteoporose/diagnóstico , Osteoporose/terapia , Humanos , Osteoporose/prevenção & controleRESUMO
While arginine-glycine-aspartic acid-based peptidomimetics have been employed for the treatment of cardiovascular disorders and cancer, their use in other contexts remains to be explored. Arginine-glycine-aspartic acid-serine induces Transforming growth factor-beta1 transcription in human mesangial cells, but the molecular mechanisms involved have not been studied extensively. We explored whether this effect could be due to Activator protein-1 activation and studied the potential pathways involved. Addition of arginine-glycine-aspartic acid-serine promoted Activator protein-1 binding to its cognate sequence within the Transforming growth factor-beta1 promoter as well as c-jun and c-fos protein abundance. Moreover, this effect was suppressed by curcumin, a c-Jun N terminal kinase inhibitor, and was absent when the Activator protein-1 cis-regulatory element was deleted. Activator protein-1 binding was dependent on the activity of integrin linked kinase, as transfection with a dominant negative mutant suppressed both Activator protein-1 binding and c-jun and c-fos protein increment. Integrin linked kinase was, in turn, dependent on Phosphoinositol-3 kinase activity. Arginine-glycine-aspartic acid-serine stimulated Phosphoinositol-3 kinase activity, and Transforming growth factor-beta1 promoter activation was abrogated by the use of Phosphoinositol-3 kinase specific inhibitors. In summary, we propose that arginine-glycine-aspartic acid-serine activates Integrin linked kinase via the Phosphoinositol-3 kinase pathway and this leads to activation of c-jun and c-fos and increased Activator protein-1 binding and Transforming growth factor-beta1 promoter activity. These data may contribute to understand the molecular mechanisms involved in the cellular actions of arginine-glycine-aspartic acid-related peptides and enhance their relevance as these products evolve into clinical therapeutic use.
Assuntos
Células Mesangiais/metabolismo , Peptídeos Cíclicos/farmacologia , Regiões Promotoras Genéticas , Transdução de Sinais/efeitos dos fármacos , Fator de Transcrição AP-1/metabolismo , Fator de Crescimento Transformador beta1/biossíntese , Regulação para Cima/efeitos dos fármacos , Doenças Cardiovasculares/tratamento farmacológico , Doenças Cardiovasculares/metabolismo , Células Cultivadas , Ativação Enzimática/efeitos dos fármacos , Ativação Enzimática/genética , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Mutação , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-fos/metabolismo , Proteínas Proto-Oncogênicas c-jun/metabolismo , Transdução de Sinais/genética , Fator de Crescimento Transformador beta1/genéticaRESUMO
Extracellular matrix (ECM) components, through specific peptide motifs such as Arg-Gly-Asp (RGD), interact with integrins and can modify the behavior of cells. Transforming growth factor-beta1 (TGF-beta1) is the main cytokine involved in the synthesis of ECM proteins. We analyzed the effect of a RGD-containing peptide, as Arg-Gly-Asp-Ser (RGDS), on the regulation of TGF-beta1 secretion in cultured human mesangial cells. We found that RGDS increased mRNA expression and secretion of TGF-beta1 by stimulating the TGF-beta1 gene promoter. This effect was dependent on the interaction of RGDS with integrins. We evaluated the signaling pathways implicated in TGF-beta1 production by analyzing the effect of RGDS on kinase-related integrins. RGDS stimulated tyrosine phosphorylation as well as integrin-linked kinase (ILK) activity. However, tyrosine kinase inhibitors did not prevent the RGDS effect. In contrast, the inhibition of ILK by cell transfection with a kinase dead-ILK completely abolished the increased TGF-beta1 secretion and promoter activity in the presence of RGDS. Thus RGDS modulates the secretion of TGF-beta1, probably through increased synthesis by interacting with integrins and activating ILK. This supports a role for ECM components in the regulation of their own secretion.
Assuntos
Integrinas/metabolismo , Oligopeptídeos/farmacologia , Fator de Crescimento Transformador beta/biossíntese , Células Cultivadas , Mesângio Glomerular/citologia , Mesângio Glomerular/metabolismo , Humanos , Modelos Biológicos , Fosforilação , Proteínas Serina-Treonina Quinases/metabolismo , RNA Mensageiro/biossíntese , Ativação Transcricional , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo , Fator de Crescimento Transformador beta1 , Tirosina/metabolismoRESUMO
The present experiments were devoted to analyzing the hypothesis that somatostatin (SS) could modulate glomerular filtration rate by interacting with mesangial cells. Studies were performed in cultured human mesangial cells, passages 3-5. Radioligand experiments demonstrated the presence in the cells of two kinds of receptors, with high (dissociation constant 14 pM. Number of sites: 426 fmol/mg) and low (dissociation constant 56 pM. Number of sites: 20, 111 fmol/mg) affinity. SS prevented in a dose-dependent manner the reduction in planar cell surface area induced by 100 nM Angiotensin II (AII). This effect was not inhibited by the blockade of the vasorelaxing prostaglandins (indomethacin, 10 microM), nitric oxide (L-N-methyl-arginine, 0.2 mM), adenylate cyclase (2,5'-dideoxyadenosine, 0.1 mM), or guanylate cyclase (Methylene blue, 30 microM; LY-83583, 10 microM), but it was potentiated by zaprinast, an inhibitor of the cyclic GMP (cGMP)-specific phosphodiesterase. SS also blocked the increase in myosin light chain phosphorylation induced by AII. SS increased cGMP synthesis by cultured human mesangial cells, an effect that seemed to be dependent on the stimulation of a particulate guanylate cyclase. Preincubation of the cells with pertussis toxin (0.5 microgram/ml) inhibited the effect of SS on the AII-dependent changes in planar cell surface area, as well as the SS-dependent cGMP stimulation. In summary, these results demonstrate the ability of SS to relax cultured human mesangial cells, thus supporting a role for this peptide in the regulation of the glomerular filtration rate. The SS-dependent mesangial cell relaxation may be due to changes in the intracellular concentrations of cGMP, as a consequence of the activation of a particulate guanylate cyclase.
Assuntos
Mesângio Glomerular/efeitos dos fármacos , Somatostatina/farmacologia , Angiotensina II/antagonistas & inibidores , Angiotensina II/farmacologia , Células Cultivadas , Taxa de Filtração Glomerular/efeitos dos fármacos , Mesângio Glomerular/citologia , Humanos , Octreotida/análogos & derivados , Octreotida/metabolismo , Testes de PrecipitinaRESUMO
Vascular smooth muscle cells (VSMC) exhibit a hypertrophic and contractile response after angiotensin II (Ang II) treatment, and the NADH/NADPH oxidase-dependent synthesis of hydrogen peroxide (H(2)O(2)) seems to play a central role in these responses. Present experiments were designed to analyze the mechanisms responsible for the rapid changes induced by Ang II in the intracellular H(2)O(2) concentration in VSMC. Ang II induced a quick and transient increase of dichlorodihydrofluorescein (DCHF) fluorescence in VSMC, an effect that was completely abolished by catalase and by diethyldithiocarbamate, a cell-permeable superoxide dismutase inhibitor. Losartan and pertussis toxin prevented the stimulatory effect of Ang II. Both diphenylene iodonium (NADH/NADPH oxidase blocker) and 3-(4-octadecylbenzoyl)acrylic acid (phospholipase A2 blocker) inhibited the changes in DCHF fluorescence induced by Ang II, in a dose-dependent fashion, and the effects of both inhibitors were additive. These data demonstrate that Ang II induces a very quick and transient increase of H(2)O(2) in VSMC. This effect depends on the receptor type 1, is linked to a G protein, and involves both NADH/NADPH oxidase and phospholipase A2 activation. The mechanism may be related to the previously proposed role of H(2)O(2) in the genesis of the Ang II-induced cell contraction.
Assuntos
Angiotensina II/farmacologia , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Acrilatos/farmacologia , Angiotensina II/metabolismo , Animais , Benzoatos , Catalase/metabolismo , Catalase/farmacologia , Células Cultivadas , Ditiocarb/farmacologia , Inibidores Enzimáticos/farmacologia , Fluoresceínas/química , Fluoresceínas/metabolismo , Fluorescência , Peróxido de Hidrogênio/metabolismo , Indometacina/farmacologia , Losartan/farmacologia , Músculo Liso Vascular/citologia , NADH NADPH Oxirredutases/antagonistas & inibidores , NADH NADPH Oxirredutases/metabolismo , Oniocompostos/farmacologia , Toxina Pertussis/farmacologia , Fosfolipases A/antagonistas & inibidores , Fosfolipases A/metabolismo , Fosfolipases A2 , Ratos , Ratos WistarRESUMO
In experimental models and in humans, somatostatin (SRIF) is able to contract certain vascular structures. The present experiments were designed to assess the capacity of SRIF to contract cultured rat aortic vascular smooth muscle cells (VSMC), and to analyze the possible mechanisms involved. Cells incubated with SRIF showed a significant reduction in planar cell surface area, in a time- and dose-dependent manner. This effect was partially blocked by preincubating the cells with a combination of calcium antagonists (10 microM verapamil, plus 10 microM 3,4,5-Trimethoxybenzoic acid 3-(diethylanino) octyl ester TMB)-8). SRIF was also able to stimulate myosin light-chain phosphorylation in VSMC. A small but significant increase of intracellular calcium concentration, and decreased levels of cAMP, without changes in cGMP, were detected in VSMC incubated with SRIF. A search for the known SRIF receptors present in these cells, by reverse transcription-polymerase chain reaction, only SRIF receptor-4 was found to be present. These results demonstrate the ability of SRIF to contract cultured rat VSMC. The contraction observed in these cells appears to be due to a mixed mechanism, that involves [Ca2+]i and cAMP as second messengers, and is likely mediated via SRIF receptor-4.
Assuntos
Músculo Liso Vascular/efeitos dos fármacos , Somatostatina/farmacologia , Animais , Sequência de Bases , Células Cultivadas , Primers do DNA , Contração Muscular/efeitos dos fármacos , Músculo Liso Vascular/fisiologia , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
Platelets seem to be involved in the pathogenesis of some kidney diseases, but the exact relationships between platelets and the changes in renal function are incompletely known. Mesangial cells (MC) were incubated with platelet-supernatants (PS) and cellular surface area (CSA) and myosin light-chain phosphorylation (MLCP) were measured. CSA of PS-incubated MC (PS-MC) significantly diminished, as compared to control MC (70 +/- 6% vs. 100 +/- 5%). PS induced a significant increase in MLCP with respect to control cells (150 +/- 23% vs. 100 +/- 18%). When platelets were pretreated with indomethacin, the PS-dependent contraction was abolished. Pretreatment with sulotroban (SU) or BN-52021 (BN), a thromboxane A2 (TXA2) and a platelet-activating factor (PAF) receptor blocker respectively, also completely blocked the PS effects. In other experiments, platelets were activated with thrombin (T), adding the so obtained PS to MC. Moreover, cells were also preincubated with T and then added PS. No changes in CSA were observed in either case. It may be concluded that PS contracted cultured MC, and these changes could be related to the decreased glomerular filtration rate (GFR) observed in some diseases in which platelets seem to be involved. TXA2 and PAF may be responsible for this effect. In contrast, T incubation inhibited the effect of PS, perhaps through a direct relaxing effect of T in MC.
Assuntos
Plaquetas/fisiologia , Mesângio Glomerular/citologia , Mesângio Glomerular/fisiologia , Animais , Células Cultivadas , Mesângio Glomerular/efeitos dos fármacos , Mesângio Glomerular/ultraestrutura , Miosinas/metabolismo , Fosforilação , Fator de Ativação de Plaquetas/farmacologia , Ratos , Ratos Wistar , Trombina/farmacologiaRESUMO
There is controversy as to the clinical importance of providing haemodialysis (HD) with biocompatible versus non-biocompatible membranes. The effects of both acute and chronic dialysis with a biocompatible membrane (polyacrylonitrile, PAN) and a non-biocompatible membrane (cuprophane, CU) on the structural and functional properties of human erythrocytes have been examined. All 27 studied HD patients had increased erythrocyte osmotic fragility (OF) compared to controls; a single CU HD decreased mean OF (% lysis) by 13% without altering cell cholesterol. A single PAN HD decreased OF by a significantly greater amount (24%) and was associated with a 20% reduction in cell cholesterol. Chronic PAN HD for 6 months was associated with a sustained reduction in osmotic fragility compared to chronic CU HD (mean lysis 16% vs 45%) with no differences in mean pre-HD cell cholesterol. A single CU HD was associated with increased mean erythrocyte malonyldialdehyde (MDA) and reduced membrane content of spectrin and band 3 and this was significantly different from the effects of PAN. A single CU or PAN HD had no significant action on reduced glutathione (GSH), ankyrin, actin or sodium pump activity. Chronic HD was associated with increased GSH, and decreased ankyrin and band 3 protein compared with controls but the results for CU and PAN were not different. There was a non-significant tendency for higher MDA levels after chronic CU HD compared to PAN. These results indicate that the structural integrity of erythrocytes is improved by PAN HD with respect to CU but this difference cannot easily be ascribed to gross changes in structural proteins, ionic homeostasis or oxidation status.
Assuntos
Resinas Acrílicas/farmacologia , Materiais Biocompatíveis/farmacologia , Celulose/análogos & derivados , Eritrócitos/citologia , Eritrócitos/fisiologia , Membranas Artificiais , Diálise Renal/instrumentação , Adulto , Celulose/farmacologia , Colesterol/sangue , Membrana Eritrocítica/metabolismo , Eritrócitos/metabolismo , Feminino , Glutationa/sangue , Humanos , Masculino , Malondialdeído/sangue , Proteínas de Membrana/sangue , Pessoa de Meia-Idade , Fragilidade Osmótica , Ouabaína/farmacologia , Sensibilidade e Especificidade , ATPase Trocadora de Sódio-Potássio/sangueRESUMO
To analyze the metabolisms of platelet-activating factor (PAF) and Thromboxane A2 (TxA2) when platelets and mesangial cells (MC) interact, immunoreactive thromboxane B2 (TxB2) and PAF were measured after incubation of cultured rat MC with platelets (P) and with platelet supernatants (PS). In both cases, TxB2 significantly decreased with respect to the P synthesis and to the PS content, suggesting an increased degradation of this metabolite or even the existence of a specific effect of MC upon platelet TxB2. When immunoreactive PAF was measured, results were comparable to those observed for TxB2. Moreover, when intrinsic mesangial cell synthesis of PAF was assessed by analyzing the [3H]-acetate incorporation by prelabeled MC in the HPLC fraction coeluting with cold PAF standards, it was possible to demonstrate that P or PS did not modify PAF synthesis in these cells. In summary, present results support the existence of a specific effect of mesangial cells upon platelet TxA2 and PAF.
Assuntos
Plaquetas/fisiologia , Mesângio Glomerular/citologia , Fator de Ativação de Plaquetas/metabolismo , Tromboxano A2/metabolismo , Animais , Comunicação Celular , Células Cultivadas , Mesângio Glomerular/fisiologia , Fator de Ativação de Plaquetas/biossíntese , Ratos , Ratos Wistar , Tromboxano A2/biossíntese , Tromboxano B2/biossíntese , Tromboxano B2/metabolismoRESUMO
It has been studied the in vitro direct action of alpha-tocopherol on osmotic fragility of red blood cells (RBCs) as well as its protective role in presence of two oxidizing drugs: phenylhydrazine hydrochloride or hydrogen peroxide. Incubation of RBCs with dl-alpha-tocopheryl acetate, at doses near to the plasma concentration in rat (6 micrograms/ml) did not modify the osmotic fragility of RBCs but increasing doses of tocopherol induces changes in osmotic fragility which directly parallelled the vitamin E concentrations. In addition, tocopherol did not protect RBCs from the hemolytic effect of the oxidizing drugs tested. Data from osmotic fragility after preincubation with dl-alpha-tocopheryl acetate and later incubation with these oxidizing drugs point to a possible toxic effect of higher dose vitamin E supplementation rather to a protective role on membrane stability.
Assuntos
Eritrócitos/efeitos dos fármacos , Vitamina E/farmacologia , Animais , Eritrócitos/fisiologia , Peróxido de Hidrogênio/farmacologia , Técnicas In Vitro , Masculino , Fragilidade Osmótica/efeitos dos fármacos , Fenil-Hidrazinas/farmacologia , Ratos , Ratos EndogâmicosRESUMO
Rats receiving daily IP injections of dl-alpha-tocopheryl acetate (50 mg/kg) for 4 days showed levels of plasma alpha-tocopherol slightly increased and normal platelet count but platelet aggregation (induced by ADP or adrenaline) was significantly decreased when compared with the control animals. In addition, both platelet-rich plasma and platelet-poor plasma-thromboelastograms from treated rats showed thromboplastine-formation times significantly higher than those from control animals. Serum biochemical parameters showed several minor modifications in treated rats with respect the control ones. It suggests that vitamin E could be considered as a possible useful tool for the therapy of several hyperaggregable or hypercoagulable states.
Assuntos
Coagulação Sanguínea/efeitos dos fármacos , Inibidores da Agregação Plaquetária/farmacologia , Vitamina E/análogos & derivados , alfa-Tocoferol/análogos & derivados , Difosfato de Adenosina/farmacologia , Fosfatase Alcalina/sangue , Animais , Proteínas Sanguíneas/metabolismo , Creatinina/sangue , Epinefrina/farmacologia , Masculino , Agregação Plaquetária/efeitos dos fármacos , Ratos , Ratos Endogâmicos , Tocoferóis , Vitamina E/farmacologiaAssuntos
Transtornos da Coagulação Sanguínea/fisiopatologia , Fenil-Hidrazinas/toxicidade , Plasma/fisiologia , Animais , Transtornos da Coagulação Sanguínea/induzido quimicamente , Plaquetas/fisiologia , Eritrócitos/fisiologia , Radicais Livres , Masculino , Oxirredução , Agregação Plaquetária , Ratos , Ratos Endogâmicos , TromboelastografiaAssuntos
Manuseio das Vias Aéreas/métodos , Intubação Intratraqueal/instrumentação , Laringoscópios , Acidentes de Trânsito , Antropometria , Broncoscopia , Tecnologia de Fibra Óptica , Fixação Interna de Fraturas , Humanos , Intubação Intratraqueal/métodos , Masculino , Pessoa de Meia-Idade , Fraturas Cranianas/etiologia , Fraturas Cranianas/cirurgia , Gravação em VídeoRESUMO
Two organisms, CCMI507 and CCMI852, degrading undecylbenzenesulphonate (LAS) by the ortho- and meta-cleavage pathways were studied in cultures where glucose was used as carbon and energy source. CCMI507 (ortho-pathway) started the degradation of LAS at the beginning of the culture development in parallel with glucose utilization. The degradation followed a steady profile of degradation until 77% of LAS was degraded in the culture containing initially 5 mg l-1 of the compound and 81% in the cultures containing initially 10 and 20 mg l-1 of LAS, after 72 h fermentation. The organism CCMI852 (meta-pathway) started degrading the compound only after 20 h, when 75% of glucose was spent and well within the stationary-phase. After 72 h fermentation the level of degradation by CCMI852 varied from 70% (5 mg l-1 of LAS) to around 75% (10 and 20 mg l-1 of LAS).
Assuntos
Benzenossulfonatos/metabolismo , Dioxigenases , Benzenossulfonatos/química , Biodegradação Ambiental , Catecol 1,2-Dioxigenase , Catecol 2,3-Dioxigenase , Fermentação , Genes Bacterianos , Glucose/metabolismo , Cinética , Oxigenases/metabolismo , Pseudomonas putida/genética , Pseudomonas putida/crescimento & desenvolvimento , Pseudomonas putida/metabolismo , Tensoativos/química , Tensoativos/metabolismoRESUMO
Erythrocytes were incubated for 60 min either in plasma or phosphate-buffered saline containing 10 mM phenylhydrazine hydrochloride. Plasma prevented the decrease in membrane fluidity observed in saline-phenylhydrazine incubated erythrocytes but these cells showed decreases in both filterability and active extrusion of Na+ that were nearly 100% lower than those found in erythrocytes incubated in plasma-phenyl-hydrazine. Also erythrocyte lipid peroxidation, as measured as thiobarbituric acid reactive products, was 100% higher in the presence of plasma. These results suggest that plasma could play "in vivo" an active role during oxidant-induced erythrocyte damage, contributing significantly to the hemolytic effects of oxidation.
Assuntos
Eritrócitos/efeitos dos fármacos , Fenil-Hidrazinas/farmacologia , Animais , Sobrevivência Celular , Técnicas In Vitro , Peroxidação de Lipídeos , Masculino , Fluidez de Membrana , Fenil-Hidrazinas/sangue , Ratos , Ratos Endogâmicos , Tiobarbitúricos/sangueRESUMO
The present experiments were designed to assess a possible role of H2O2 in the proliferation of cultured rat mesangial cells, as well as to evaluate the effect of different calcium channel blockers and a platelet-activating factor antagonist on this proliferation. Cultured rat mesangial cells were plated at two densities (10,000 and 25,000 cells/well) in 24-well dishes, and proliferation was measured by analyzing [3H]thymidine incorporation and by directly counting the cells. Hydrogen peroxide, 100 microM, increased [3H]thymidine incorporation at the two densities tested (85 and 59%, respectively), as well as the number of cells (53 and 23%, respectively). This effect was dose dependent and it was blocked completely by verapamil and diltiazem, 10 microM, but not by TMB-8 [3,4,5-trimethoxybenzoic acid 8-(diethylamino) octyl ester] at the same concentration. BN 52021, a competitive antagonist of platelet-activating factor, only slightly blocked the H2O2-dependent proliferation. The inhibitory action of the two calcium antagonists tested started at concentrations as low as 1 nM, and inhibited completely the H2O2 stimulated proliferation at concentrations between 0.1 and 1 microM. These results establish that H2O2 is able to induce proliferation of mesangial cells. Although the pathophysiological implications of this finding remain to be proven, these data suggest a potential therapeutic action of calcium antagonist in inflammatory conditions such as glomerulonephritis.
Assuntos
Bloqueadores dos Canais de Cálcio/farmacologia , Diterpenos , Mesângio Glomerular/citologia , Mesângio Glomerular/efeitos dos fármacos , Peróxido de Hidrogênio/antagonistas & inibidores , Animais , Contagem de Células , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Diltiazem/farmacologia , Ginkgolídeos , Peróxido de Hidrogênio/farmacologia , Cinética , Lactonas/farmacologia , Fator de Ativação de Plaquetas/antagonistas & inibidores , Fator de Crescimento Derivado de Plaquetas/farmacologia , Ratos , Ratos Wistar , Trombina/farmacologia , Timidina/metabolismo , Timidina/farmacocinética , Trítio , Verapamil/farmacologiaRESUMO
Chromosomal studies in CLL have yielded poorer results than in other blood diseases because of the low mitotic index of the B cells. The FISH technique is a very useful tool for trisomy 12 detection in interphase nuclei in CLL, although this method cannot be a substitutive for conventional cytogenetics. The FISH technique was applied in two cases of CLL by means of satellite DNA probing specific for chromosome 12 according to the Oncor S 1370-CF kit protocol. Trisomy 12 was detected, along with other chromosomal abnormalities secondary to this trisomy. Both patients had lymphocyte counts lower than 5.0 x 10(9)/L and their peripheral blood immunophenotype showed 58% lymphocytes with lambda sIg of medium density, co-expressing CD5 and unable to form rosettes with mouse red-cells. Patient no. 1 was 46,XY/47,XY + 12/47,XY + 12,5q-, and patient no. 2 was 46,XX/47,XX + 12,14q-. The presence of secondary anomalies could explain the special clinico-haematological picture, characterised by low lymphocytosis and presence of irregular nuclei in mature lymphocytes, along with the lack of CD23 expression and rosette formation with mouse red-cells. FISH technique combined with chromosome analysis may prove a useful means for diagnosing and recognising variants or specific entities within low-grade lymphoproliferative syndromes.