RESUMO
AIMS: This study aimed to investigate the dynamics and physiological heterogeneity of Oenococcus oeni under different conditions, cell membrane fluidity and permeability variations, and assessment of changes in cell surface charging rates. METHODS AND RESULTS: Flow cytometry, membrane fatty acid analysis and capillary electrophoresis were performed to study ethanol-induced variations. Different physiological states were assessed, revealing cell subpopulations able to adapt and withstand to environmental stress, in order to recover their functionality. Moreover, total results demonstrated changes in cell surface and membrane fatty acid redistribution with a saturation degree and an unsaturated/saturated fatty acid ratio fairly steady in control and in different ethanol stresses. CONCLUSIONS: This study revealed a great variability among O. oeni strains and the importance to investigate the mechanisms by a multiparametric approach based on the structural and physiological bacterial adjustments in different stresses tolerance. SIGNIFICANCE AND IMPACT OF THE STUDY: Intermediate physiological state assessment in O. oeni with recovery possibility could be an important criterion for potential starter culture application. The flow cytometry application with changes in monitoring membrane fatty acid composition and in surface charging rates allowed the characterization of sorted subpopulations that may contribute to further understanding of diversity and heterogeneity in physiology of bacterial populations.
Assuntos
Ácidos Graxos/metabolismo , Oenococcus/metabolismo , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Eletroforese Capilar , Etanol/metabolismo , Etanol/farmacologia , Ácidos Graxos/análise , Fermentação , Citometria de Fluxo , Fluidez de Membrana/efeitos dos fármacos , Oenococcus/fisiologia , Estresse Fisiológico , Vinho/microbiologiaRESUMO
The radon prone areas definition is matter of many researches in radioecology, since radon is considered a leading cause of lung tumours, therefore the authorities ask for support to develop an appropriate sanitary prevention strategy. In this paper, we use geostatistical tools to elaborate a definition accounting for some of the available information about the dwellings. Co-kriging is the proper interpolator used in geostatistics to refine the predictions by using external covariates. In advance, co-kriging is not guaranteed to improve significantly the results obtained by applying the common lognormal kriging. Here, instead, such multivariate approach leads to reduce the cross-validation residual variance to an extent which is deemed as satisfying. Furthermore, with the application of Monte Carlo simulations, the paradigm provides a more conservative radon prone areas definition than the one previously made by lognormal kriging.
Assuntos
Poluentes Radioativos do Ar/análise , Poluição do Ar em Ambientes Fechados/análise , Monitoramento de Radiação/métodos , Radônio/análise , Habitação , Análise EspacialRESUMO
Studying the geographical distribution of indoor radon concentration, using geostatistical interpolation methods, has become common for predicting and estimating the risk to the population. Here we analyse the case of Friuli Venezia Giulia (FVG), the north easternmost region of Italy. Mean value and standard deviation are, respectively, 153 Bq/m(3) and 183 Bq/m(3). The geometric mean value is 100 Bq/m(3). Spatial datasets of indoor radon concentrations are usually affected by clustering and apparent non-stationarity issues, which can eventually yield arguable results. The clustering of the present dataset seems to be non preferential. Therefore the areal estimations are not expected to be affected. Conversely, nothing can be said on the non stationarity issues and its effects. After discussing the correlation of geology with indoor radon concentration It appears they are created by the same geologic features influencing the mean and median values, and can't be eliminated via a map-based approach. To tackle these problems, in this work we deal with multiple definitions of RPA, but only in quaternary areas of FVG, using extensive simulation techniques.
Assuntos
Poluentes Radioativos do Ar/análise , Poluição do Ar em Ambientes Fechados/análise , Monitoramento de Radiação/métodos , Radônio/análise , Mapeamento Geográfico , Itália , Modelos EstatísticosRESUMO
AIMS: The aim of this study was to investigate the effect of ethanol exposure on the expression level of geranylgeranyl pyrophosphate synthase gene involved in the metabolism of Oenococcus oeni to probe the mechanisms of ethanol tolerance correlated with adaptive changes. METHODS AND RESULTS: The evaluation of ten potential internal control genes and the comparative study of their stability were performed to select the most stable internal controls for the normalization of expression data. The expression level analysis by qPCR and changes after exposure to ethanol stresses highlighted a significant increase in the presence of higher ethanol concentrations. CONCLUSIONS: The analysis of results suggest that O. oeni adjusts the expression of genes to adapt to stress conditions and the high expression level of ggpps would allow a flow of isoprenoid precursors towards the carotenoids and related pathways to stabilize bacterial cell membranes, improving the cell membrane disturbances and preventing cell death induced by ethanol. SIGNIFICANCE AND IMPACT OF THE STUDY: The involvement of ggpps gene in physiological changes of bacterial behaviour confirmed the exposure to stress requires the activation of defence mechanism to be more tolerant to adverse conditions. Improving the knowledge of stress tolerance and adaptation mechanisms of O. oeni is essential to enhance the efficiency of the malolactic starter in wine and to obtain the development of starters able to survive to direct inoculation with a large benefit for wine technology.
Assuntos
Etanol , Oenococcus , Etanol/metabolismo , Fermentação , Geranil-Geranildifosfato Geranil-Geraniltransferase , Malatos/metabolismo , Oenococcus/metabolismo , Vinho/microbiologiaRESUMO
Acute inhibition of serotonergic (5-HT) neurons in the medullary raphé (MR) using a 5-HT(1A) receptor agonist had an age-dependent impact on the "CO(2) response" of piglets (33). Our present study explored the effect of chronic 5-HT neuron lesions in the MR and extra-raphé on the ventilatory response to hypercapnia and hypoxia in piglets, with possible implications on the role of 5-HT in the sudden infant death syndrome. We established four experimental groups. Group 1 (n = 11) did not undergo any treatment. Groups 2, 3, and 4 were injected with either vehicle or the neurotoxin 5,7-dihydroxytryptamine in the cisterna magna during the first week of life (group 2, n = 9; group 4, n = 11) or second week of life (group 3, n = 10). Ventilation was recorded in response to 5% CO(2) (all groups) and 12% O(2) (group 2) during wakefulness and sleep up to postnatal day 25. Surprisingly, the piglets did not reveal changes in their CO(2) sensitivity during early postnatal development. Overall, considerable lesions of 5-HT neurons (up to 65% decrease) in the MR and extra-raphé had no impact on the CO(2) response, regardless of injection time. Postlesion raphé plasticity could explain why we observed no effect. 5,7-Dihydroxytryptamine-treated males, however, did present a lower CO(2) response during sleep. Hypoxia significantly altered the frequency during sleep in lesioned piglets. Further studies are necessary to elucidate the role of plasticity, sex, and 5-HT abnormalities in sudden infant death syndrome.
Assuntos
Hipercapnia/fisiopatologia , Hipóxia/fisiopatologia , Bulbo/fisiopatologia , Ventilação Pulmonar/fisiologia , Morte Súbita do Lactente/etiologia , 5,7-Di-Hidroxitriptamina/farmacologia , Animais , Animais Recém-Nascidos , Dióxido de Carbono , Modelos Animais de Doenças , Feminino , Humanos , Hipercapnia/patologia , Hipóxia/patologia , Recém-Nascido , Masculino , Bulbo/efeitos dos fármacos , Bulbo/patologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Ventilação Pulmonar/efeitos dos fármacos , Núcleos da Rafe/efeitos dos fármacos , Núcleos da Rafe/metabolismo , Núcleos da Rafe/patologia , Respiração/efeitos dos fármacos , Mecânica Respiratória/efeitos dos fármacos , Mecânica Respiratória/fisiologia , Serotonina/metabolismo , Fatores Sexuais , Fases do Sono/efeitos dos fármacos , Fases do Sono/fisiologia , Morte Súbita do Lactente/patologia , SuínosRESUMO
Acute lung injury is frequent after severe peritonitis. The aim of this study was to investigate whether inhibition of the adhesion molecule CD11-CD18 on polymorphonuclear leukocytes (PMNs) would have any beneficial effects on pulmonary function and mortality in an animal model reproducing these clinical conditions. Acute peritonitis was induced in 36 rabbits by intraperitoneal injection of zymosan (0.6 g/kg) suspended in mineral oil; 20 were pretreated with a murine-specific IgG2a anti-CD18 monoclonal antibody, 16 (controls) with nonspecific purified murine IgG (1 mg/kg). The animals were followed for 10 d, then killed for histologic examination of the lungs. Blood samples were taken on Days 0, 1, 3, 7, and 10 for red blood cell (RBC), white blood cell (WBC), and platelet counts, pH, PO(2), PCO(2), carbon dioxide content (HCO(3)(-)) measurements, and renal and liver tests. Treatment with the anti-CD18 monoclonal antibody reduced mortality by approximately 40% (p < 0.05). PO(2) was higher in these treated animals than in the control animals throughout the study (p < 0.05 on Day 1, 3, and 10). On Day 1 control animals had significant leukopenia, whereas anti-CD18-treated animals had a moderate increase of the number of circulating WBC compared with baseline values (p < 0.05 between groups). The lungs of the anti-CD18-treated animals showed minor signs of inflammation and PMN infiltration whereas controls had interstitial and intra-alveolar edema and a large number of granulocytes. Quantification of PMNs by morphometry showed that there were constantly less granulocytes in the lungs of the animals treated with the anti-CD18 antibody (p < 0.001). PMN infiltration correlated with the levels of PO(2) (p < 0.001). Lung tissue of anti-CD18-treated rabbits contained less malonyldialdehyde, a by-product of membrane lipid peroxidation by PMN oxygen radicals (950 +/- 120 versus 1,710 +/- 450 pM/mg of protein) and, conversely, more of the antioxidant alpha-tocopherol (136 +/- 22 versus 40 +/- 9 ng/mg of protein), than the control rabbits (p < 0.01). In this particular model of ARDS the monoclonal antibody against the CD11-CD18 complex had a beneficial effect, reducing PMN infiltration and oxygen radical release in the lungs, preventing alveolocapillary membrane damage, improving gas exchange and, finally, significantly reducing mortality.
Assuntos
Anticorpos Monoclonais/farmacologia , Antígenos CD11/imunologia , Antígenos CD18/imunologia , Moléculas de Adesão Celular/imunologia , Imunoglobulina G/farmacologia , Insuficiência de Múltiplos Órgãos/patologia , Peritonite/patologia , Síndrome do Desconforto Respiratório/patologia , Animais , Pulmão/patologia , Masculino , Insuficiência de Múltiplos Órgãos/mortalidade , Peritônio/patologia , Peritonite/mortalidade , Coelhos , Síndrome do Desconforto Respiratório/mortalidade , Taxa de SobrevidaRESUMO
There is controversial evidence suggesting that the classical pathway of complement system is chronically activated in primary biliary cirrhosis (PBC) and that complement activation may be important in development of bile duct injury. We have reevaluated this issue by measuring by-products of complement activation such as C4a, C3a, Bb, and terminal complement complexes (SC5b-9) in plasma of 44 PBC patients with sensitive methods not previously used to detect complement activation in this disease. Age-matched healthy women and patients with chronic hepatitis of different etiology were studied as controls. We found that PBC patients have normal C4a concentrations. This finding argues strongly against chronic classical pathway activation. Although a minor increase of C3a levels was observed in a minority of PBC patients, the C3a/C3 ratio, an index used to evaluate the extent of native protein conversion, was remarkably similar in all groups. Potentially lytic terminal complement complexes were not increased. PBC patients had normal Bb plasma levels, indicating that the alternative pathway is also not activated. C3 concentration was higher in PBC patients than in healthy subjects and in chronic hepatitis patients, particularly in the early stages of the disease. C3 and C4 concentrations became lower in PBC and chronic hepatitis with the progression of the disease. The increase of C3 concentration in PBC does not reflect liver inflammation, since serum levels of C-reactive protein are normal. We found high serum C3 levels in patients with rare chronic cholestatic syndromes without superimposed infections and observed that serum C3 levels paralleled those of bilirubin in a patient with benign recurrent intrahepatic cholestasis. In conclusion, our data indicate that complement is not activated in PBC and that the increase of serum C3 levels is related to cholestasis.
Assuntos
Ativação do Complemento , Via Clássica do Complemento , Cirrose Hepática Biliar/imunologia , Adulto , Idoso , Proteína C-Reativa/metabolismo , Complemento C3/metabolismo , Complemento C3a/metabolismo , Complemento C4/metabolismo , Complemento C4a/metabolismo , Progressão da Doença , Feminino , Humanos , Cirrose Hepática Biliar/sangue , Masculino , Pessoa de Meia-Idade , Sensibilidade e EspecificidadeAssuntos
Proteínas do Sistema Complemento/fisiologia , Doença das Coronárias/sangue , Anafilatoxinas/farmacologia , Angina Pectoris/sangue , Animais , Ativação do Complemento/efeitos dos fármacos , Circulação Coronária/efeitos dos fármacos , Doença das Coronárias/fisiopatologia , Modelos Animais de Doenças , Venenos Elapídicos/farmacologia , Fibrinolíticos/farmacologia , Humanos , Infarto do Miocárdio/sangue , Infarto do Miocárdio/prevenção & controle , Traumatismo por Reperfusão Miocárdica/sangueRESUMO
BACKGROUND: We have previously shown that treatment with streptokinase induces abrupt complement activation and transient neutropenia in patients with acute myocardial infarction (AMI). The purpose of this study was to compare the effects of two different thrombolytic agents--streptokinase (SK) and recombinant tissue-type plasminogen activator (rTPA)--on activation of the complement and kinin systems in plasma of patients with AMI. METHODS AND RESULTS: Forty-one patients with AMI who were eligible for thrombolytic therapy were studied. Twenty-three patients were treated with streptokinase (1.5 million IU IV over 60 minutes) and 18 were treated with rTPA (8 with bolus of 10 mg IV, followed by 50 mg infused over 60 minutes and then 40 mg infused over 120 minutes; 10 patients were administered rTPA and heparin according to the accelerated infusion protocol indicated by the GUSTO study). C4a and C3a were measured by radioimmunoassay, soluble terminal complement components (SC5b-9) and anti-SK IgG antibodies were measured by ELISA. Cleaved high molecular weight kininogen (HK) was quantitated in plasma by SDS-PAGE and immunoblotting analysis. C4a levels were significantly and similarly increased in both groups, whereas the levels of C3a and SC5b-9 after rTPA infusion were only slightly elevated and were significantly lower than after SK. No differences were observed between patients treated with slow or accelerated rTPA regimens. The titer of antibodies to SK was highly correlated with the levels of C3a and SC5b-9, whereas a lesser correlation was observed with C4a. Treatment with rTPA did not induce the transient neutropenia observed after SK infusion. The cleavage products of HK were significantly greater after SK than after rTPA infusion. CONCLUSIONS: Our results show that both thrombolytic agents activate the classic complement pathway and that plasmin could be the common trigger for this phenomenon. A significant activation of the complement common pathway (from C3 to terminal components) was observed only with SK infusion and is attributable to the rapid formation of immunocomplexes between SK and anti-SK antibodies present in plasma as a consequence of previous streptococcal infections. The minimal activation of C5 component of the common pathway explains the absence of leukopenia in patients treated with rTPA. Cleavage of HK, larger after SK than after rTPA infusion, represents a condition enhancing the generation of bradykinin by kallikrein. The recent experimental data that indicate a damaging effect of complement activation on the infarcted zone and the contrasting favorable effect consequent to bradykinin formation raise some questions about the clinical importance of the different biological consequences of SK versus rTPA.
Assuntos
Ativação do Complemento , Cininas/fisiologia , Infarto do Miocárdio/fisiopatologia , Infarto do Miocárdio/terapia , Estreptoquinase/uso terapêutico , Terapia Trombolítica , Ativador de Plasminogênio Tecidual/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Ativação do Complemento/efeitos dos fármacos , Complemento C3a/análise , Complemento C4a/análise , Complexo de Ataque à Membrana do Sistema Complemento , Proteínas do Sistema Complemento/análise , Feminino , Glicoproteínas/análise , Humanos , Cininogênios/química , Cininogênios/fisiologia , Contagem de Leucócitos/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Proteínas RecombinantesRESUMO
Details of possible complement activation in acute myocardial infarction (AMI) and the in vivo effects of fibrinolytic agents on this activation are not yet known. We measured complement activation in 40 patients with AMI: 20 were treated with streptokinase, and 20 did not receive any fibrinolytic agent. Anaphylatoxin C4a, C3a and membrane attack complexes SC5b-9 increased about 10-fold (p < 0.0001) during streptokinase infusion. There were no increases in complement catabolic products in AMI patients not treated with streptokinase. Significant transient leukopenia (-29.5%, 7.0 SEM, p = 0.001) and a drop in systolic pressure (-29%, 3.4 SEM, p < 0.0001) occurred after 15 min of streptokinase infusion simultaneously with the peak of anaphylatoxins in plasma.
Assuntos
Ativação do Complemento , Terapia Trombolítica , Anafilatoxinas/análise , Pressão Sanguínea , Ativação do Complemento/efeitos dos fármacos , Complemento C3a/análise , Complemento C4a/análise , Complemento C5a/análise , Complexo de Ataque à Membrana do Sistema Complemento , Proteínas do Sistema Complemento/análise , Glicoproteínas/análise , Humanos , Técnicas Imunoenzimáticas , Infusões Intravenosas , Contagem de Leucócitos , Infarto do Miocárdio/tratamento farmacológico , Infarto do Miocárdio/imunologia , Radioimunoensaio , Estreptoquinase/administração & dosagem , Estreptoquinase/farmacologiaRESUMO
BACKGROUND: Whether and to what extent complement is activated in acute myocardial infarction (AMI) and how it contributes to inflammation of the ischemic area are not yet clear. Fibrinolytic agents used for thrombolysis are known to activate complement in vitro and may contribute to its activation in vivo. The aim of this study was to measure the extent of complement activation in AMI patients, some treated and some not treated with streptokinase. In addition, because abrupt complement activation in vivo is usually associated with leukocyte margination, plugging of cells in the microcirculation, and hypotension, we correlated complement activation with leukocyte numbers and mean arterial pressure. METHODS AND RESULTS: Forty AMI patients were studied: 20 were treated with streptokinase (1.5 million IU IV over 60 minutes), and 20 were not given any fibrinolytic agent. The extent and severity of AMI were not significantly different in both groups. Blood samples were drawn on arrival at the hospital, during streptokinase infusion, and then daily for 1 week. Time-matched samples were also drawn from patients not treated with streptokinase. We measured plasma levels of anaphylatoxin C4a, C3a, and C5a by radioimmunoassay and membrane attack complexes SC5b-9 by enzyme immunoassay. Leukocytes and arterial pressure also were measured when samples were obtained. C4a, C3a, and SC5b-9 levels increased about 10-fold (P < .0001) during infusion of streptokinase. There were no significant increases in complement catabolic products in AMI patients not treated with streptokinase. There was a significant transient leukopenia (mean +/- SEM, -29.5 +/- 7.0%; P = .001) and decreases in systolic and diastolic pressures (systolic, -29.3 +/- 3.2%, P < .0001; diastolic, -27.5 +/- 3.4%, P < .0001) after 15 minutes of streptokinase infusion in coincidence with the peak of anaphylatoxins in plasma. CONCLUSIONS: Streptokinase treatment of AMI causes abrupt activation of the complement system, whereas no significant complement activation can be detected in plasma of AMI patients not treated with fibrinolytic agents. Complement activation causes a transient leukopenia, as reported for such other clinical conditions as dialysis and cardiopulmonary bypass, and possibly contributes to the hypotension observed during streptokinase treatment.
Assuntos
Ativação do Complemento/efeitos dos fármacos , Hipotensão/induzido quimicamente , Infarto do Miocárdio/tratamento farmacológico , Neutropenia/induzido quimicamente , Estreptoquinase/uso terapêutico , Idoso , Anafilatoxinas/análise , Pressão Sanguínea/efeitos dos fármacos , Complexo de Ataque à Membrana do Sistema Complemento , Proteínas do Sistema Complemento/análise , Feminino , Glicoproteínas/análise , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/imunologia , Fatores de TempoRESUMO
Antibodies to gliadin, detected by immunofluorescence (IFL-AGA) and ELISA (ELISA-AGA), have been found in 68 of 71 (96%) sera from children with active celiac disease. AGA of IgA class were confined to celiac disease on normal diet and after gluten challenge, as all the antibodies, found in children on gluten free diet (40%) and in control gastroenterological diseases (20%), were of IgG class. Sera from 175 first-degree relatives of our celiacs were also screened for AGA. IFL-AGA were positive in 13 (7%) and ELISA-AGA in 27 cases (15%). Antibodies were of IgA class in 13 relatives (7%). A celiac's asymptomatic sister, selected for jejunal biopsy only on the basis of IgA AGA positivity, showed subtotal villous atrophy. Although AGA cannot replace jejunal biopsy in the diagnosis of celiac disease, they can be regarded as useful tools in the screening of gluten sensitive enteropathy. Moreover, as a positive IgA AGA test is closely related to the active phases of celiac disease, their research can be useful both to evaluate the effect of gluten free diet and to establish when a new biopsy is appropriate after gluten challenge.