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1.
J Card Surg ; 37(9): 2592-2599, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35775747

RESUMO

BACKGROUND: Remote ischemic preconditioning (rIPC) has been applied to attenuate tissue injury. We tested the hypothesis that rIPC applied to fetal lambs undergoing cardiac bypass (CB) reduces fetal systemic inflammation and placental dysfunction. METHODS: Eighteen fetal lambs were divided into three groups: sham, CB control, and CB rIPC. CB rIPC fetuses had a hindlimb tourniquet applied to occlude blood flow for four cycles of a 5-min period, followed by a 2-min reperfusion period. Both study groups underwent 30 min of normothermic CB. Fetal inflammatory markers, gas exchange, and placental and fetal lung morphological changes were assessed. RESULTS: The CB rIPC group achieved higher bypass flow rates (p < .001). After CB start, both study groups developed significant decreases in PaO2 , mixed acidosis, and increased lactate levels (p < .0004). No significant differences in tissular edema were observed on fetal lungs and placenta (p > .391). Expression of Toll-like receptor 4 and intercellular adhesion molecule-1 in the placenta and fetal lungs did not differ among the three groups, as well as with vascular cell adhesion molecule-1 (VCAM-1) of fetal lungs (p > .225). Placental VCAM-1 expression was lower in the rIPC group (p < .05). Fetal interleukin-1 (IL-1) and thromboxane A2 (TXA2) levels were lower at 60 min post-CB in the CB rIPC group (p < .05). There were no significant differences in tumor necrosis factor-α, prostaglandin E2, IL-6, and IL-10 plasma levels of the three groups at 60-min post-bypass (p > .133). CONCLUSION: Although rIPC allowed increased blood flow during fetal CB and decreased IL-1 and TXA2 levels and placental VCAM-1, it did not prevent placental dysfunction in fetal lambs undergoing CB.


Assuntos
Precondicionamento Isquêmico , Molécula 1 de Adesão de Célula Vascular , Animais , Feminino , Feto , Interleucina-1 , Placenta , Gravidez , Ovinos
2.
Pulm Pharmacol Ther ; 61: 101901, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32044433

RESUMO

BACKGROUND: Lung transplantation is a treatment method for end stage lung disease, but the availability of donor lungs remains a major constraint. Brain death (BD) induces hemodynamic instability with microcirculatory hypoperfusion and increased inflammation, leading to pulmonary dysfunction. Hypertonic saline solution (HSS) is a volume expander possessing immunomodulatory effects. This study evaluated the influence of HSS on pulmonary dysfunction and inflammation in a rat model of BD. METHODS: BD was induced by inflation of an intracranial balloon catheter. Rats were divided into [1]: Sham, without BD [2]; NS, NaCl treatment (0.9%, 4 mL/kg, i.v.) immediately after BD [3]; HSS1, HSS treatment (NaCl 7.5%, 4 mL/kg, i.v.) immediately after BD; and [4] HSS60, HSS treatment 60 min post BD. All groups were analyzed after 360 min. RESULTS: Animals subjected to BD exhibited increased exhaled O2 and decreased CO2.The number of leukocytes in the lungs was significantly increased in the NS group (p = 0.002) and the HSS treatment was able to reduce it (HSS1, p = 0.018 and HSS60 = 0.030). In parallel, HSS-treated rats showed reduced levels of ICAM-1 expression, which was increased in the NS compared to Sham group. Lung edema was found increased in the NS group animals compared to Sham and no effect of the HSS treatment was observed. There were no differences among the groups in terms of TNF-α, VEGF, and CINC-1 lung concentrations. CONCLUSIONS: HSS is capable of reducing inflammatory cell infiltration into the lung after BD induction, which is associated with the reduction of ICAM-1 expression in organ vessels.


Assuntos
Morte Encefálica , Pulmão/fisiopatologia , Solução Salina Hipertônica/uso terapêutico , Animais , Pressão Arterial , Quimiocina CXCL1/metabolismo , Edema , Endotelina-1/metabolismo , Molécula 1 de Adesão Intercelular/metabolismo , Pulmão/metabolismo , Pulmão/patologia , Transplante de Pulmão , Masculino , Óxido Nítrico Sintase Tipo III/metabolismo , Ratos , Ratos Wistar , Fator de Necrose Tumoral alfa/metabolismo , Molécula 1 de Adesão de Célula Vascular/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
3.
Transpl Int ; 33(11): 1541-1550, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32890430

RESUMO

Brain death (BD) leads to a systemic inflammation associated with the activation of coagulation, which could be related to decreased microcirculatory perfusion. Evidence shows that females exhibit higher platelet aggregability than males. Thus, we investigated sex differences in platelets, coagulation and microcirculatory compromise after BD. BD was induced in male and female (proestrus) Wistar rats. After 3 h, we evaluated: (i) intravital microscopy to evaluate mesenteric perfusion and leucocyte infiltration; (ii) platelet aggregation assay; (iii) rotational thromboelastometry; and (iv) Serum NOx- . Female rats maintained the mesenteric perfusion, whereas male reduced percentage of perfused vessels. Male BD presented higher platelet aggregation than the controls. In contrast, female BD had lower platelet aggregation than the control. Thromboelastometry indicated a reduction in clot firmness with increased clotting time in the female group compared with the male group. Serum NOx- level in female BD was higher than that in the male BD and female control. There is sex dimorphism in platelet function and clotting process, which are altered in different ways by BD. Thus, it is possible to connect the reduction in microcirculatory perfusion in males to intravascular microthrombi formation and the maintenance of perfusion in females to a higher inflammatory response and NO synthesis.


Assuntos
Morte Encefálica , Caracteres Sexuais , Animais , Feminino , Masculino , Microcirculação , Perfusão , Ratos , Ratos Wistar
4.
Transpl Int ; 33(10): 1312-1321, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32621784

RESUMO

The viability of donor organs is reduced by hemodynamic and immunologic alterations caused by brain death (BD). Female rats show higher heart inflammation associated with the reduction in female sex hormones after BD. This study investigated the effect of 17ß-estradiol (E2) on BD-induced cardiac damage in female rats. Groups of female Wistar rats were assigned: Sham-operation (Sham), brain death (BD), treatment with E2 (50 µg/ml, 2 ml/h) 3 h after BD (E2-T3), or immediately after BD confirmation (E2-T0). White blood cell (WBC) count was analyzed; cytokines and troponin-I were quantified. Heart histopathological changes and expression of endothelial nitric oxide synthase, endothelin-1, intercellular adhesion molecule-1, BCL-2, and caspase-3 were evaluated. Cardiac function was continuously assessed for 6 h by left ventricular pressure-volume loop analysis. E2 decreased the BD-induced median serum concentration of troponin-I (BD:864.2 vs. E2-T0:401.4; P = 0.009), increased BCL-2 (BD:0.086 vs. E2-T0:0.158; P = 0.0278) and eNOS median expression in the cardiac tissue (BD:0.001 vs. E2-T0:0.03 and E2-T3:0.0175; P < 0.0001), and decreased caspase-3 (BD:0.025 vs. E2-T0:0.006 and E2-T3:0.019; P = 0.006), WBC counts, leukocyte infiltration, and hemorrhage. 17ß-estradiol treatment was effective in reducing cardiac tissue damage in brain-dead female rats owing to its ability to reduce leukocyte infiltration and prevent cardiomyocyte apoptosis.


Assuntos
Morte Encefálica , Transplante de Coração , Animais , Estradiol/farmacologia , Feminino , Humanos , Ratos , Ratos Wistar , Doadores de Tecidos
5.
Transpl Int ; 33(3): 279-287, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31701582

RESUMO

Organ donor's age negatively influences graft survival of organs, increasing risk of complications. Aging occurs in both men and women; however, the menopause marks a decrease in sex hormones and a sudden increase in the process of vascular aging. We investigated sex hormones' influence on the lung inflammatory process induced by BD in female rats. Wistar rats were grouped as: female rats from high estradiol to heat period (non-OVx) and ovariectomized (OVx) female rats. Ovariectomy was carried out 10 days before BD. BD was induced using intracranial balloon rapid inflation. Serum hormones and inflammatory mediators were quantified, leukocytes and platelets counted and lung samples were collected for RT-PCR, immunohistochemical, and histological analysis. Female sex hormones and corticosterone were reduced 6 h after BD in non-OVx group. The infiltration of leukocytes in female non-OVx lungs was higher compared to OVx. G-CSF, VEGF, and CINC-1 were found increased in non-OVx group serum in comparison to OVx. Lung mediators were increased in non-OVx rats compared to controls. The acute reduction of sex hormones induced by BD appears to have a worse effect on lung inflammation than a reduction that has happened over a prolonged period of time, allowing a physiological adaptation prior to BD.


Assuntos
Morte Encefálica , Pneumonia , Animais , Estradiol , Feminino , Hormônios Esteroides Gonadais , Pneumonia/etiologia , Ratos , Ratos Wistar
6.
J Surg Res ; 235: 8-15, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30691854

RESUMO

BACKGROUND: Brain death (BD) in potential organ donors is responsible for hemodynamic instability and organ hypoperfusion, leading to myocardial dysfunction. Hypertonic saline (HS) is a volume expander with positive effects on hemodynamics and immunomodulation and was tested in this study to prevent left ventricular (LV) dysfunction and myocardial injury. METHODS: BD was induced in anesthetized Wistar rats by inflating a subdural balloon catheter, except in sham-operated animals (n = 6). After BD induction, Control animals received only normal saline solution (NaCl 0.9%, 4 mL/kg; n = 6), and treated animals were divided to receive HS (NaCl, 7.5% 4 mL/kg) at 1 min (HS1, n = 6) or 60 min (HS60, n = 6) thereafter. We continuously assessed cardiac function for 6 h with LV pressure-volume analysis. Inflammatory response, markers of myocardial injury, and cellular apoptosis-related proteins were investigated. RESULTS: BD was associated with decreased LV systolic and diastolic function. In comparison with the Control group, HS treatments improved LV ejection fraction (HS1, 51% [40-66]; HS60, 71% [28-82]; Control, 46% [23-55]; P < 0.05) and other parameters of LV systolic function 6 h after BD induction. However, no ventricular relaxation advantages were observed during the same period. HS treatments increased antiapoptotic protein expression and decreased vascular adhesion molecule and tumor necrosis factor alpha expression. No significant differences in histologic or structural protein changes were observed between groups. CONCLUSIONS: The observed data suggest that HS ameliorates LV systolic dysfunction and seems to reduce myocardial tissue compromise in BD rats, even when the treatment is performed during the process triggered by this event.


Assuntos
Morte Encefálica/fisiopatologia , Miocárdio/patologia , Solução Salina Hipertônica/uso terapêutico , Disfunção Ventricular Esquerda/prevenção & controle , Animais , Morte Encefálica/patologia , Hemodinâmica/efeitos dos fármacos , Masculino , Ratos , Ratos Wistar , Sódio/sangue
7.
J Vasc Surg ; 67(2): 597-606, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28385296

RESUMO

OBJECTIVE: In surgical aortic repair or cardiac surgery with aorta occlusion, the occurrence of mesenteric ischemia and bowel injury has been associated with higher short-term mortality. The vascular protection of estrogens has been investigated and is mainly mediated by increasing the availability of nitric oxide (NO). Therefore, this study investigated the role of 17ß-estradiol on visceral ischemia-reperfusion (I/R) injury after descending aorta occlusion in male rats. METHODS: Mesenteric ischemia was induced in male Wistar rats by placing a 2F Fogarty arterial embolectomy catheter (Edwards Lifesciences, Irvine, Calif) in the descending aorta, which remained occluded for 15 minutes, followed by reperfusion for up to 2 hours. Rats were divided into four groups: (1) rats that underwent surgical manipulation only (sham, n = 22); (2) rats that underwent I/R injury (n = 22); (3) rats treated with intravenous 17ß-estradiol (280 µg/kg) 30 minutes before I/R (n = 22); (4) or at the beginning of reperfusion (n = 22). Intestinal histopathologic changes were evaluated by histomorphometry. Mesenteric microcirculatory alterations were assessed by laser Doppler flowmetry and intravital microscopy technique. Protein expression of intercellular adhesion molecule-1, P-selectin, endothelial NO synthase (eNOS), and endothelin-1 was evaluated by immunohistochemistry; in addition, eNOS and endothelin-1 gene expressions were quantified by real-time polymerase chain reaction. Serum cytokines were measured by enzyme-linked immunosorbent assay. RESULTS: Relative to the sham group, the I/R group exhibited a highly pronounced loss of intestine mucosal thickness, a reduction in mesenteric blood flow (P = .0203), increased migrated leukocytes (P < .05), and high mortality rate (35%). Treatment with 17ß-estradiol before aorta occlusion preserved intestine mucosal thickness (P = .0437) and mesenteric blood flow (P = .0251), reduced the number of migrated leukocytes (P < .05), and prevented any fatal occurrence. Furthermore, 17ß-estradiol downregulated the expression of intercellular adhesion molecule-1 (P = .0001) and P-selectin (P < .0001) on the endothelium and increased the protein expression of eNOS (P < .0001). The gene expressions of eNOS and endothelin-1 did not differ between the groups. CONCLUSIONS: The prophylactic treatment with 17ß-estradiol showed better overall repercussions and was able to prevent any fatal occurrence, increase eNOS expression, thus preserving mesenteric perfusion and intestinal integrity, and reduce inflammation.


Assuntos
Aorta/fisiopatologia , Oclusão com Balão/efeitos adversos , Estradiol/farmacologia , Íleo/irrigação sanguínea , Íleo/efeitos dos fármacos , Isquemia Mesentérica/prevenção & controle , Traumatismo por Reperfusão/prevenção & controle , Circulação Esplâncnica/efeitos dos fármacos , Animais , Modelos Animais de Doenças , Endotelina-1/metabolismo , Íleo/metabolismo , Íleo/patologia , Molécula 1 de Adesão Intercelular/metabolismo , Masculino , Isquemia Mesentérica/etiologia , Isquemia Mesentérica/metabolismo , Isquemia Mesentérica/fisiopatologia , Óxido Nítrico Sintase Tipo III/metabolismo , Selectina-P/metabolismo , Ratos Wistar , Traumatismo por Reperfusão/etiologia , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/fisiopatologia , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo
8.
Int J Exp Pathol ; 98(3): 158-165, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28749083

RESUMO

Experimental findings support the evidence of a persistent leucopenia triggered by brain death (BD). This study aimed to investigate leucocyte behaviour in bone marrow and blood after BD in rats. BD was induced using intracranial balloon catheter inflation. Sham-operated (SH) rats were trepanned only. Thereafter bone marrow cells were harvested every six hours from the femoral cavity and used for total and differential counts. They were analysed further by flow cytometry to characterize lymphocyte subsets, granulocyte adhesion molecules expression and apoptosis/necrosis [annexin V/propidium iodide (PI) protocol]. BD rats exhibited a reduction in bone marrow cells due to a reduction in lymphocytes (40%) and segmented cells (45%). Bone marrow lymphocyte subsets were similar in BD and SH rats (CD3, P = 0.1; CD4, P = 0.4; CD3/CD4, P = 0.4; CD5, P = 0.4, CD3/CD5, P = 0.2; CD8, P = 0.8). Expression of L-selectin and beta2 -integrins on granulocytes did not differ (CD11a, P = 0.9; CD11b/c, P = 0.7; CD62L, P = 0.1). There were no differences in the percentage of apoptosis and necrosis (Annexin V, P = 0.73; PI, P = 0.21; Annexin V/PI, P = 0.29). In conclusion, data presented suggest that the downregulation of the bone marrow is triggered by brain death itself, and it is not related to changes in lymphocyte subsets, granulocyte adhesion molecules expression or apoptosis and necrosis.


Assuntos
Células da Medula Óssea/patologia , Morte Encefálica/patologia , Animais , Apoptose , Células da Medula Óssea/imunologia , Células da Medula Óssea/metabolismo , Morte Encefálica/imunologia , Morte Encefálica/metabolismo , Moléculas de Adesão Celular/metabolismo , Modelos Animais de Doenças , Regulação para Baixo , Granulócitos/metabolismo , Hemodinâmica/fisiologia , Contagem de Leucócitos , Leucopenia/etiologia , Subpopulações de Linfócitos/imunologia , Masculino , Necrose , Ratos Wistar
9.
Acta Cardiol Sin ; 33(3): 315-322, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28630534

RESUMO

The International Committee of Medical Journal Editors (ICMJE) provides recommendations to improve the editorial standards and scientific quality of biomedical journals. These recommendations range from uniform technical requirements to more complex and elusive editorial issues including ethical aspects of the scientific process. Recently, registration of clinical trials, conflicts of interest disclosure, and new criteria for authorship- emphasizing the importance of responsibility and accountability-, have been proposed. Last year, a new editorial initiative to foster sharing of clinical trial data was launched. This review discusses this novel initiative with the aim of increasing awareness among readers, investigators, authors and editors belonging to the Editors' Network of the European Society of Cardiology.

10.
J Surg Res ; 200(2): 714-21, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26547667

RESUMO

BACKGROUND: Donor sex has been suggested to be a factor influencing organ transplantation outcome. Sex hormones possess inflammatory and immune-mediating properties; therefore, immune responses may differ between males and females. Brain death (BD) affects organ function by numerous mechanisms including alterations in hemodynamics, hormonal changes, and increased systemic inflammation. In this study, we investigated sex-dependent differences in the evolution of lung inflammation in a rat model of BD. MATERIALS AND METHODS: BD was induced by a sudden increase in intracranial pressure by rapidly inflating a balloon catheter inserted into the intracranial space. Groups of male, female, and ovariectomized (OVx) female rats were used. Lung vascular permeability, inducible nitric oxide synthase, and intercellular adhesion molecule 1 expression were analyzed 6 h after BD. Serum female sex hormones, vascular endothelial growth factor, and cytokine-induced neutrophil chemoattractant 1 levels were also quantified. Lung sections were analyzed by histology. RESULTS: After 6 h of BD, serum estradiol and progesterone concentrations in female rats were significantly reduced. Lung microvascular permeability was increased in females compared to males. Cytokine-induced neutrophil chemoattractant 1 and vascular endothelial growth factor concentrations were increased in female rats compared to males. Furthermore, female rats showed higher levels of leukocyte infiltration and inducible nitric oxide synthase expression in the lung parenchyma. CONCLUSIONS: Our results indicate that the more severe lung inflammation in female animals after BD might be related to acute estradiol reduction. Based on our findings, we believe that, in a future study, a group of female treated with estradiol after BD could indicate a possible therapy for the control of lung inflammation in the female donor.


Assuntos
Morte Encefálica/metabolismo , Pneumonia/metabolismo , Animais , Biomarcadores/metabolismo , Estradiol/sangue , Feminino , Pulmão/metabolismo , Pulmão/patologia , Masculino , Pneumonia/etiologia , Pneumonia/patologia , Progesterona/sangue , Ratos , Ratos Wistar , Fatores Sexuais , Obtenção de Tecidos e Órgãos
11.
Magn Reson Chem ; 54(10): 800-804, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27198972

RESUMO

Time-domain nuclear magnetic resonance and chemometrics were used to predict color parameters, such as lightness (L*), redness (a*), and yellowness (b*) of beef (Longissimus dorsi muscle) samples. Analyzing the relaxation decays with multivariate models performed with partial least-squares regression, color quality parameters were predicted. The partial least-squares models showed low errors independent of the sample size, indicating the potentiality of the method. Minced procedure and weighing were not necessary to improve the predictive performance of the models. The reduction of transverse relaxation time (T2 ) measured by Carr-Purcell-Meiboom-Gill pulse sequence in darker beef in comparison with lighter ones can be explained by the lower relaxivity Fe2+ present in deoxymyoglobin and oxymyoglobin (red beef) to the higher relaxivity of Fe3+ present in metmyoglobin (brown beef). These results point that time-domain nuclear magnetic resonance spectroscopy can become a useful tool for quality assessment of beef cattle on bulk of the sample and through-packages, because this technique is also widely applied to measure sensorial parameters, such as flavor, juiciness and tenderness, and physicochemical parameters, cooking loss, fat and moisture content, and instrumental tenderness using Warner Bratzler shear force. Copyright © 2016 John Wiley & Sons, Ltd.

12.
Biol Sex Differ ; 15(1): 11, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38287395

RESUMO

BACKGROUND: Ex vivo lung perfusion (EVLP) is a useful tool for assessing lung grafts quality before transplantation. Studies indicate that donor sex is as an important factor for transplant outcome, as females present higher inflammatory response to brain death (BD) than males. Here, we investigated sex differences in the lungs of rats subjected to BD followed by EVLP. METHODS: Male and female Wistar rats were subjected to BD, and as controls sham animals. Arterial blood was sampled for gas analysis. Heart-lung blocks were kept in cold storage (1 h) and normothermic EVLP carried out (4 h), meanwhile ventilation parameters were recorded. Perfusate was sampled for gas analysis and IL-1ß levels. Leukocyte infiltration, myeloperoxidase presence, IL-1ß gene expression, and long-term release in lung culture (explant) were evaluated. RESULTS: Brain dead females presented a low lung function after BD, compared to BD-males; however, at the end of the EVLP period oxygenation capacity decreased in all BD groups. Overall, ventilation parameters were maintained in all groups. After EVLP lung infiltrate was higher in brain dead females, with higher neutrophil content, and accompanied by high IL-1ß levels, with increased gene expression and concentration in the culture medium (explant) 24 h after EVLP. Female rats presented higher lung inflammation after BD than male rats. Despite maintaining lung function and ventilation mechanics parameters for 4 h, EVLP was not able to alter this profile. CONCLUSION: In this context, further studies should focus on therapeutic measures to control inflammation in donor or during EVLP to increase lung quality.


As there is a shortage of viable lungs for transplantation, methods of lung preservation, such as ex vivo perfusion, are important. This method is a good alternative, as it will not only preserve the lungs, but also enable lung function assessment and treatment of the organs. Studies have showed that lungs from donors of the female sex have greater risk of being rejected, when transplanted to male receptors. However, it's not certain if sex differences in anatomy, physiology and specially in immune response could interfere with the transplant result. Females do present a greater and more efficient immune response to any hazard, however after brain death this control is lost, producing a great inflammatory response as a result. Therefore, in this study we have investigated in more detail the influence of sex on the effects of brain death followed by the preservation method. Thus, we performed a brain death model in males and females rats and placed their lungs in an ex vivo lung perfusion machine. At the end of the experiment, we analyzed lung ventilation, gas exchange, and inflammatory parameters. The obtained data indicated that overall the lung ventilation and gas exchange is maintained by the ex vivo perfusion machine. Also, that lung inflammation is influenced by the sex of the donor; where the lungs from females present greater inflammation compared to the lungs from males.


Assuntos
Morte Encefálica , Transplante de Pulmão , Feminino , Masculino , Animais , Ratos , Preservação de Órgãos , Ratos Wistar , Pulmão , Perfusão
13.
Anal Chim Acta ; 1263: 341259, 2023 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-37225345

RESUMO

Recently, rare-earth elements (REEs) have attracted great interest due to their importance in several fields, such as the high-technology and medicine industries. Due to the recent intensification of the use of REEs in the world and the resulting potential impact on the environment, new analytical approaches for their determination, fractionation and speciation are needed. Diffusive gradients in thin films are a passive technique already used for sampling labile REEs, providing in situ analyte concentration, fractionation and, consequently, remarkable information on REE geochemistry. However, data based on DGT measurements until now have been based exclusively on the use of a single binding phase (Chelex-100, immobilized in APA gel). The present work proposes a new method for the determination of rare earth elements using an inductively coupled plasma‒mass spectrometry technique and a diffusive gradients in thin films (DGT) technique for application in aquatic environments. New binding gels were tested for DGT using carminic acid as the binding agent. It was concluded that acid dispersion directly in agarose gel presented the best performance, offering a simpler, faster, and greener method for measuring labile REEs compared to the existing DGT binding phase. Deployment curves obtained by immersion tests in the laboratory show that 13 REEs had linearity in their retention by the developed binding agent (retention x time), confirming the main premise of the DGT technique obeying the first Fick's diffusion law. For the first time, the diffusion coefficients were obtained in agarose gels (diffusion medium) and carminic acid immobilized in agarose as the binding phase for La, Ce, Pr, Nd, Sm, Eu, Gd, Dy, Ho, Er, Tm, Yb and Lu, which were 3.94 × 10-6, 3.87 × 10-6, 3.90 × 10-6, 3.79 × 10-6, 3.71 × 10-6, 4.13 × 10-6, 3.75 × 10-6, 3.94 × 10-6, 3.45 × 10-6, 3.97 × 10-6, 3.25 × 10-6, 4.06 × 10-6, and 3.50 × 10-6 cm2 s-1, respectively. Furthermore, the proposed DGT devices were tested in solutions with different pH values (3.5, 5.0, 6.5 and 8) and ionic strengths (I = 0.005 mol L-1, 0.01 mol L-1, 0.05 mol L-1 and 0.1 mol L-1 - NaNO3). The results of these studies showed an average variation in the analyte retention for all elements at a maximum of approximately 20% in the pH tests. This variation is considerably lower than those previously reported when using Chelex resin as a binding agent, particularly for lower pH values. For the ionic strength, the maximum average variation was approximately 20% for all elements (except for I = 0.005 mol L-1). These results indicate the possibility of a wide range of the proposed approach to be used for in situ deployment without the use of correction based on apparent diffusion coefficients (as required for using the conventional approach). In laboratory deployments using acid mine drainage water samples (treated and untreated), it was shown that the proposed approach presents excellent accuracy compared with data obtained from Chelex resin as a binding agent.

14.
Eur J Cardiothorac Surg ; 64(3)2023 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-37410160

RESUMO

OBJECTIVES: Ischaemia and reperfusion-induced microvascular dysfunction is a serious problem encountered during a variety surgical procedures, leading to systemic inflammation and affecting remote organs, specially the lungs. 17ß-Oestradiol reduces pulmonary repercussions from various acute lung injury forms. Here, we focused on the 17ß-oestradiol therapeutic effects after aortic ischaemia and reperfusion (I/R) by evaluating lung inflammation. METHODS: Twenty-four Wistar rats were submitted to I/R by insufflation of a 2-F catheter in thoracic aorta for 20 min. Reperfusion took 4 h and 17ß-oestradiol (280 µg/kg, i.v.) was administered after 1 h of reperfusion. Sham-operated rats were controls. Bronchoalveolar lavage was performed and lung samples were prepared for histopathological analysis and tissue culture (explant). Interleukin (IL)-1ß, IL-10 and tumour necrosis factor-α were quantified. RESULTS: After I/R, higher number of leukocytes in bronchoalveolar lavage were reduced by 17ß-oestradiol. The treatment also decreased leukocytes in lung tissue. I/R increased lung myeloperoxidase expression, with reduction by 17ß-oestradiol. Serum cytokine-induced neutrophil chemoattractant 1 and IL-1ß increased after I/R and 17ß-oestradiol decreased cytokine-induced neutrophil chemoattractant 1. I/R increased IL-1ß and IL-10 in lung explants, reduced by 17ß-oestradiol. CONCLUSIONS: Our results showed that 17ß-oestradiol treatment performed in the period of reperfusion, modulated the systemic response and the lung repercussions of I/R by thoracic aortic occlusion. Thus, we can suggest that 17ß-oestradiol might be a supplementary approach leading the lung deterioration after aortic clamping in surgical procedures.


Assuntos
Lesão Pulmonar , Traumatismo por Reperfusão , Ratos , Masculino , Animais , Estradiol/farmacologia , Estradiol/uso terapêutico , Estradiol/metabolismo , Lesão Pulmonar/tratamento farmacológico , Lesão Pulmonar/etiologia , Ratos Wistar , Interleucina-10/uso terapêutico , Aorta Torácica/patologia , Pulmão/patologia , Isquemia , Citocinas/metabolismo , Fatores Quimiotáticos/metabolismo , Fatores Quimiotáticos/uso terapêutico , Síndrome de Resposta Inflamatória Sistêmica
15.
Clinics (Sao Paulo) ; 78: 100222, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37257364

RESUMO

BACKGROUND: Clinical reports associate kidneys from female donors with worse prognostic in male recipients. Brain Death (BD) produces immunological and hemodynamic disorders that affect organ viability. Following BD, female rats are associated with increased renal inflammation interrelated with female sex hormone reduction. Here, the aim was to investigate the effects of sex on BD-induced Acute Kidney Injury (AKI) using an Isolated Perfused rat Kidney (IPK) model. METHODS: Wistar rats, females, and males (8 weeks old), were maintained for 4h after BD. A left nephrectomy was performed and the kidney was preserved in a cold saline solution (30 min). IPK was performed under normothermic temperature (37°C) for 90 min using WME as perfusion solution. AKI was assessed by morphological analyses, staining of complement system components and inflammatory cell markers, perfusion flow, and creatinine clearance. RESULTS: BD-male kidneys had decreased perfusion flow on IPK, a phenomenon that was not observed in the kidneys of BD-females (p < 0.0001). BD-male kidneys presented greater proximal (p = 0.0311) and distal tubule (p = 0.0029) necrosis. However, BD-female kidneys presented higher expression of eNOS (p = 0.0060) and greater upregulation of inflammatory mediators, iNOS (p = 0.0051), and Caspase-3 (p = 0.0099). In addition, both sexes had increased complement system formation (C5b-9) (p=0.0005), glomerular edema (p = 0.0003), and nNOS (p = 0.0051). CONCLUSION: The present data revealed an important sex difference in renal perfusion in the IPK model, evidenced by a pronounced reduction in perfusate flow and low eNOS expression in the BD-male group. Nonetheless, the upregulation of genes related to the proinflammatory cascade suggests a progressive inflammatory process in BD-female kidneys.


Assuntos
Injúria Renal Aguda , Transplante de Rim , Ratos , Feminino , Masculino , Animais , Morte Encefálica/metabolismo , Ratos Wistar , Rim/metabolismo , Perfusão
16.
Rev Assoc Med Bras (1992) ; 69(10): e20221694, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37729220

RESUMO

OBJECTIVE: The aim of this study was to compare the capacity of American Thyroid Association and Thyroid Imaging Reporting and Data System developed by the American College of Radiology in predicting malignancy risk of thyroid nodules and to verify which one is better at avoiding unnecessary fine needle aspiration. METHODS: This was a cross-sectional study with 565 thyroid nodules, followed at a tertiary care hospital, in an iodine-replete area. Those were classified as American Thyroid Association and Thyroid Imaging Reporting and Data System developed by the American College of Radiology systems and stratified according to the Bethesda classification of fine needle aspiration. The values of sensibility, specificity, positive predictive value, and negative predictive value accuracy were calculated. Also, the percentage of unnecessary biopsies was presented. RESULTS: The mean age of the individuals was 58.2±13.5 [26-90] years for benign nodules and 41.7±15.6 [23-66] years for malignant nodules (p=0.002). Regarding gender, 92.6% (n=150) of the individuals with benign nodules and 85.7% (n=06) with malignant nodules were females (p=0.601). For American Thyroid Association, 90.9% of sensibility, 51.4% of specificity, 52.6% of accuracy, 10.2% of positive predictive value, and 98.9% of negative predictive value were found. For Thyroid Imaging Reporting and Data System developed by the American College of Radiology, 90.9% of sensibility, 49.7% of specificity, 52.1% of accuracy, 9.9% of positive predictive value, and 98.9% of negative predictive value were found. .Notably, 12.3% of unnecessary fine needle aspiration were found in American Thyroid Association and 44.4% were found in Thyroid Imaging Reporting and Data System developed by the American College of Radiology. CONCLUSION: Both Thyroid Imaging Reporting and Data System developed by the American College of Radiology and American Thyroid Association are able to predict the malignancy risk of thyroid nodules. Thyroid Imaging Reporting and Data System developed by the American College of Radiology was better at avoiding unnecessary fine needle aspiration.


Assuntos
Radiologia , Nódulo da Glândula Tireoide , Feminino , Humanos , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Masculino , Nódulo da Glândula Tireoide/diagnóstico por imagem , Sistemas de Dados , Estudos Transversais , Biópsia por Agulha Fina
17.
Sci Rep ; 13(1): 2084, 2023 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-36747073

RESUMO

The aims of this study were to perform pre-surgery miRNA profiling of patients who develop Vasoplegic syndrome (VS) after coronary artery bypass grafting (CABG) and identify those miRNAs that could be used as VS prognostic tools and biomarkers. The levels of 754 microRNAs (miRNAs) were measured in whole blood samples from a cohort of patients collected right before the coronary artery bypass grafting (CABG) surgery. We compared the miRNA levels of those who developed VS (VASO group) with those who did not (NONVASO group) after surgery. Six miRNAs (hsa-miR-548c-3p, -199b-5p, -383-5p -571 -183-3p, -30d-5p) were increased and two (hsa-1236-3p, and hsa-miR770-5p) were decreased in blood of VASO compared to NONVASO groups. Receiver Operating Characteristic (ROC) curve analysis revealed that a combination of the miRNAs, hsa-miR-30d-5p and hsa-miR-770-5p can be used as VS predictors (AUC = 0.9615, p < 0.0001). The computational and functional analyses were performed to gain insights into the potential role of these dysregulated miRNAs in VS and have identified the "Apelin Liver Signaling Pathway" as the canonical pathway containing the most target genes regulated by these miRNAs. The expression of the combined miRNAs hsa-miR-30d and hsa-miR-770-5p allowed the ability to distinguish between patients who could and could not develop VS, representing a potential predictive biomarker of VS.


Assuntos
MicroRNAs , Vasoplegia , Humanos , Vasoplegia/genética , MicroRNAs/metabolismo , Biomarcadores , Prognóstico , Transdução de Sinais , Perfilação da Expressão Gênica
18.
Eur J Cardiothorac Surg ; 61(6): 1337-1345, 2022 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-34957507

RESUMO

OBJECTIVES: Pulmonary arterial hypertension (PAH) is a cardiopulmonary disease that affects the pulmonary vasculature, leading to increased afterload and eventually right ventricular (RV) remodelling and failure. Bilateral sympathectomy (BS) has shown promising results in dampening cardiac remodelling and dysfunction in several heart failure models. In the present study, we investigated whether BS reduces pulmonary arterial remodelling and mitigates RV remodelling and failure. METHODS: PAH was induced in male Wistar rats by intraperitoneal injection of monocrotaline. Rats were divided into 3 groups, involving untreated PAH (n = 15), BS-treated PAH (n = 13) and non-manipulated control rats (n = 13). Three weeks after PAH induction, the rats were anaesthetized and RV function was assessed via the pressure-volume loop catheter approach. Upon completion of the experiment, the lungs and heart were harvested for further analyses. RESULTS: BS was found to prevent pulmonary artery remodelling, with a clear reduction in α-smooth muscle actin and endothelin-1 expression. RV end-systolic pressure was reduced in the BS group, and preload recruitable stroke work was preserved. BS, therefore, mitigated RV remodelling and cardiomyocyte hypertrophy and diminished oxidative stress. CONCLUSIONS: We showed that thoracic BS may be an important treatment option for PAH patients. Blockade of the sympathetic pathway can prevent pulmonary remodelling and protect the RV from oxidative stress, myocardial remodelling and function decay.


Assuntos
Hipertensão Pulmonar , Hipertensão Arterial Pulmonar , Disfunção Ventricular Direita , Animais , Modelos Animais de Doenças , Hipertensão Pulmonar Primária Familiar , Humanos , Masculino , Estresse Oxidativo , Artéria Pulmonar , Ratos , Ratos Wistar , Simpatectomia , Remodelação Vascular , Função Ventricular Direita , Remodelação Ventricular
19.
Int Immunopharmacol ; 113(Pt A): 109311, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36252489

RESUMO

As a consequence of systemic inflammation caused by ischemia and reperfusion (I/R) due to aortic occlusion, the lungs can exhibit increased microvascular permeability, local release of pro-inflammatory mediators, and leukocyte infiltration. Lung tissue infiltration by activated neutrophils is followed by acute respiratory distress syndrome, which is linked to acute pulmonary microvascular damage, high mortality rates, and organ dysfunction. Previous studies have demonstrated that female sex hormones modulate the inflammatory response and that prophylactic treatment with 17ß-estradiol (E2) can prevent fatalities and preserve mesenteric perfusion and intestinal integrity after ischemia/reperfusion induced by aortic occlusion. In this study, we focused on the protective effects of estradiol after aortic ischemia/reperfusion by evaluating lung injury and endothelial alterations. Upon anesthesia and mechanical ventilation, male rats were subjected to aortic occlusion for 20 min, followed by 2 h of reperfusion. In parallel, one group of rats received a single injection of estradiol (280 µg/kg, i.v.) 30 min before ischemia. We observed increased serum concentrations of IL-1ß, IL-6 and IL-10 in the I/R rats and E2 was able to reduce them. E2 effects after 2 h of reperfusion resulted mainly in decreasing of edema, iNOS expression and preventing leukocyte infiltration. Overall, our data indicate that estradiol might be a supplementary approach to deal with systemic processes and lung deterioration.


Assuntos
Pneumonia , Traumatismo por Reperfusão , Ratos , Masculino , Feminino , Animais , Traumatismo por Reperfusão/metabolismo , Aorta Torácica , Ratos Wistar , Pneumonia/tratamento farmacológico , Pneumonia/etiologia , Estradiol/farmacologia , Estradiol/uso terapêutico , Estradiol/metabolismo , Pulmão , Isquemia/metabolismo
20.
Transplantation ; 106(2): 289-298, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33859149

RESUMO

BACKGROUND: Brain death (BD) is associated with systemic inflammatory compromise, which might affect the quality of the transplanted organs. This study investigated the expression profile of cardiac microRNAs (miRNAs) after BD, and their relationship with the observed decline in myocardial function and with the changes induced by hypertonic saline solution (HSS) treatment. METHODS: Wistar rats were assigned to sham-operation (SHAM) or submitted to BD with and without the administration of HSS. Cardiac function was assessed for 6 h with left ventricular (LV) pressure-volume analysis. We screened 641 rodent miRNAs to identify differentially expressed miRNAs in the heart, and computational and functional analyses were performed to compare the differentially expressed miRNAs and find their putative targets and their related enriched canonical pathways. RESULTS: An enhanced expression in canonical pathways related to inflammation and myocardial apoptosis was observed in BD induced group, with 2 miRNAs, miR-30a-3p, and miR-467f, correlating with the level of LV dysfunction observed after BD. Conversely, HSS treated after BD and SHAM groups showed similar enriched pathways related to the maintenance of heart homeostasis regulation, in agreement with the observation that both groups did not have significant changes in LV function. CONCLUSIONS: These findings highlight the potential of miRNAs as biomarkers for assessing damage in BD donor hearts and to monitor the changes induced by therapeutic measures like HSS, opening a perspective to improve graft quality and to better understand the pathophysiology of BD. The possible relation of BD-induced miRNA's on early and late cardiac allograft function must be investigated.


Assuntos
Transplante de Coração , MicroRNAs , Animais , Morte Encefálica , Transplante de Coração/efeitos adversos , Humanos , MicroRNAs/genética , Ratos , Ratos Wistar , Solução Salina Hipertônica/farmacologia , Solução Salina Hipertônica/uso terapêutico , Doadores de Tecidos
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