Brain stem death induces pro-inflammatory cytokine production and cardiac dysfunction in sheep model.

INTRODUCTION: Organs procured following brain stem death (BSD) are the main source of organ grafts for transplantation. However, BSD is associated with inflammatory responses that may damage the organ and affect both the quantity and quality of organs available for transplant. Therefore, we aimed to investigate plasma and bronchoalveolar lavage (BAL) pro-inflammatory cytokine profiles and cardiovascular physiology in a clinically relevant 6-h ovine model of BSD. METHODS: Twelve healthy female sheep (37-42 Kg) were anaesthetized and mechanically ventilated prior to undergoing BSD induction and then monitored for 6 h. Plasma and BAL endothelin-1 and cytokines (IL-1ß, 6, 8 and tumour necrosis factor alpha (TNF-α)) were assessed by ELISA. Differential white blood cell counts were performed. Cardiac function during BSD was also examined using echocardiography, and cardiac biomarkers (A-type natriuretic peptide and troponin I were measured in plasma. RESULTS: Plasma concentrations big ET-1, IL-6, IL-8, TNF-α and BAL IL-8 were significantly (p < 0.01) increased over baseline at 6 h post-BSD. Increased numbers of neutrophils were observed in the whole blood (3.1 × 109 cells/L [95% confidence interval (CI) 2.06-4.14] vs. 6 × 109 cells/L [95%CI 3.92-7.97]; p < 0.01) and BAL (4.5 × 109 cells/L [95%CI 0.41-9.41] vs. 26 [95%CI 12.29-39.80]; p = 0.03) after 6 h of BSD induction vs baseline. A significant increase in ANP production (20.28 pM [95%CI 16.18-24.37] vs. 78.68 pM [95%CI 53.16-104.21]; p < 0.0001) and cTnI release (0.039 ng/mL vs. 4.26 [95%CI 2.69-5.83] ng/mL; p < 0.0001), associated with a significant reduction in heart contractile function, were observed between baseline and 6 h. CONCLUSIONS: BSD induced systemic pro-inflammatory responses, characterized by increased neutrophil infiltration and cytokine production in the circulation and BAL fluid, and associated with reduced heart contractile function in ovine model of BSD.

Endothelin receptor antagonist improves donor lung function in an ex vivo perfusion system.

BACKGROUND: A lung transplant is the last resort treatment for many patients with advanced lung disease. The majority of donated lungs come from donors following brain death (BD). The endothelin axis is upregulated in the blood and lung of the donor after BD resulting in systemic inflammation, lung damage and poor lung graft outcomes in the recipient. Tezosentan (endothelin receptor blocker) improves the pulmonary haemodynamic profile; however, it induces adverse effects on other organs at high doses. Application of ex vivo lung perfusion (EVLP) allows the development of organ-specific hormone resuscitation, to maximise and optimise the donor pool. Therefore, we investigate whether the combination of EVLP and tezosentan administration could improve the quality of donor lungs in a clinically relevant 6-h ovine model of brain stem death (BSD). METHODS: After 6 h of BSD, lungs obtained from 12 sheep were divided into two groups, control and tezosentan-treated group, and cannulated for EVLP. The lungs were monitored for 6 h and lung perfusate and tissue samples were processed and analysed. Blood gas variables were measured in perfusate samples as well as total proteins and pro-inflammatory biomarkers, IL-6 and IL-8. Lung tissues were collected at the end of EVLP experiments for histology analysis and wet-dry weight ratio (a measure of oedema). RESULTS: Our results showed a significant improvement in gas exchange [elevated partial pressure of oxygen (P = 0.02) and reduced partial pressure of carbon dioxide (P = 0.03)] in tezosentan-treated lungs compared to controls. However, the lungs hematoxylin-eosin staining histology results showed minimum lung injuries and there was no difference between both control and tezosentan-treated lungs. Similarly, IL-6 and IL-8 levels in lung perfusate showed no difference between control and tezosentan-treated lungs throughout the EVLP. Histological and tissue analysis showed a non-significant reduction in wet/dry weight ratio in tezosentan-treated lung tissues (P = 0.09) when compared to control. CONCLUSIONS: These data indicate that administration of tezosentan could improve pulmonary gas exchange during EVLP.

Anti-inflammatory and immune properties of the peltatoside, isolated from the leaves of Annona crassiflora Mart., in a new experimental model zebrafish.

Establishing new animal models for the study of inflammation is very important in the process of discovering new drugs, since the inflammatory event is the basis of many pathological processes. Whereas rodent models have been the primary focus of inflammation research, we defend the zebrafish (Danio rerio) test as a feasible alternative for preclinical studies. Moreover, despite all the technological development already achieved by humanity, nature can still be considered a relevant source of new medicines. In this context, the aim of this work was to evaluate the anti-inflammatory effect of a substance isolated from the medicinal plant Annona crassilfora Mart, the peltatoside, in an inflammatory model of zebrafish. It was determined: (i) total leukocyte count in the coelomate exudate; (ii) N-acetyl-ß-d-glucuronidase (NAG); (iii) myeloperoxidase (MPO); (iv) and the histology of liver, intestine and mesentery. Peltotoside (25, 50 and 100 µg) and dexamethasone (25 µg) were administered intracelomatically (i.c.) 30 min before carrageenan (i.c.). Pretreatment with peltatoside at three doses significantly inhibited leukocyte recruitment in the coelomic cavity, and inhibited NAG and MPO activity against the action of Cg, in a similar manner as dexamethasone. However, some microlesions in the evaluated organs were detected. The dose of 25 µg showed an anti-inflammatory effect with lower undesirable effects in the tissues. Our results suggest that the zebrafish test was satisfactory in performing our analyzes and that the peltotoside has a modulatory action in reducing leukocyte migration.

Acquired von Willebrand syndrome in respiratory extracorporeal life support: a systematic review of the literature.

BACKGROUND AND OBJECTIVE: Venovenous extracorporeal membrane oxygenation (VV ECMO) and extracorporeal CO2 removal (ECCO2R) are increasingly used in the management of severe respiratory failure. With bleeding complications being one of the major risks of these techniques, our aim in this systematic review was to assess the available literature on acquired von Willebrand syndrome (AvWS) and extracorporeal support. AvWS has previously been associated with bleeding and shear stress. DESIGN AND DATA SOURCES: A systematic review, using Medline via PubMed, was performed to identify eligible studies up to January 2017. RESULTS AND CONCLUSION: The prevalence of AvWF among patients on VV ECMO or ECCO2R is high, but only a limited number of studies are reported in the literature. AvWS testing should be performed, including vWF multimer analysis, vWF activity and vWF antigen concentration. The extent to which vWF contributes to bleeding during ECMO, or how much changes in ECMO management can influence high molecular weight vWF multimer levels, cannot be answered from the currently available evidence and there remains a need for future studies.

Aporphine alkaloids and feruloylamides from the bark of Xylopia benthamii R.E. Fries (Annonaceae).

The bark of Xylopia benthamii R.E. Fries was investigated in a search for new bioactive compounds. The ethanolic extract of the air-dried bark of X. benthamii was obtained and submitted to an acidic extraction procedure to obtain an alkaloid mixture. Chromatographic fractionation led to the isolation of two aporphine alkaloids, nornantenine and laurotetanine, and a mixture of trans- and cis-feruloyltyramine, isolated for the first time in this genus. Structures were established by spectroscopic methods as NMR (1D and 2D) and mass spectrometry (ESI-MS).

Avaliação da atividade citotóxica das sementes de Annona cornifolia A. St.-Hil. (Annonaceae) / Evaluation of the cytotoxic activity of seeds of Annona cornifolia A. St.-Hil. (Annonaceae)

Na família Annonaceae, especialmente o gênero Annona é muito apreciado por fornecer frutos comestíveis. Espécies desse gênero são utilizadas na medicina popular contra diabetes, malária e infecções. Muitas dessas atividades biológicas têm sido relacionadas às acetogeninas de anonáceas. O objetivo deste estudo foi avaliar a atividade citotóxica dos grupos e de uma acetogenina pura (cornifolina) obtidos a partir do extrato etanólico das sementes de Annona cornifolia A. St.-Hil. (Annonaceae). Esta atividade foi avaliada pelo ensaio colorimétrico MTT. Cornifolina (1), a única substância pura testada, apresentou citotoxicidade positiva sobre todas as linhagens tumorais avaliadas. Os grupos testados, todos caracterizados por espectroscopia no infravermelho (IV), apresentaram 68,7% dos valores de CI50 menores que 20,0 µg mL-1, sendo também considerados citotóxicos. As amostras testadas foram mais ativas que o taxol sobre melanoma humano (MeWo) e, ainda, o grupo G10-5 apresentou melhor atividade sobre fibroblasto tumorigênico de camundongo (L929). Além disso, os grupos mostraram menor citotoxidade do que o taxol sobre a linhagem normal (CHO).

The family Annonaceae, especially the genus Annona, is greatly appreciated for providing edible fruits. Species of this genus are used in folk medicine against diabetes, malaria and infections. Many of these biological activities have been related to annonaceous acetogenins. The aim of this study was to evaluate the cytotoxic activity of groups and a pure acetogenin (cornifolin) obtained from the ethanol extract of the seeds of Annona cornifolia A. St.-Hil. (Annonaceae). This activity was evaluated by using MTT colorimetric assay. Cornifolin (1), the only tested substance that was pure, showed positive cytotoxicity on all evaluated tumor cell lines. The tested groups, all characterized by infrared spectroscopy (IR), showed 68.7% of the IC50 values lower than 20.0 µg mL-1, also considered cytotoxic. The tested samples were more active than taxol on human melanoma (MeWo) and the group G10-5 showed better activity on mouse tumorigenic fibroblast (L929). In addition, the tested groups showed less cytotoxicity than taxol on the normal line (CHO).

Decarboxylation of oxidized single-wall carbon nanotubes.

A classical protocol widely used in organic chemistry of aromatic and polyaromatic molecules has been successfully applied in this work for the decarboxylation of oxidized single-wall carbon nanotube (SWNT) to rend C-H SWNT derivatives. SWNT produced by arc discharge method have been oxidized during a purification process using strongly oxidant agents, such as hydrogen peroxide and nitric acid. The decarboxylation of oxidized SWNT has been conduced with copper(I) oxide in a 50:50 solution of N-methylpyrrolidone and quinoline. Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy and acid-base potentiometric titration analyses were carried out to characterize quali and quantitatively the changes in the chemical environment on the SWNT surface in each step of the purification and the decarboxylation process. Those techniques showed the appearance of mainly carboxylic and phenolic groups after the purification process and the disappearance of the carboxylic groups after the decarboxylation reaction. Fourier transform infrared spectroscopy analysis indicated also the formation of aliphatic and aromatic C-H groups. X-ray photoelectron spectroscopy and potentiometric titration results determined an efficiency higher than 90% for our decarboxylation procedure. The purity and structural quality of the SWNT sample used in the decarboxylation process were evaluated by thermogravimetry and Raman spectroscopy. Thermogravimetric analysis identified a purified sample with approximately 80 wt% of SWNT, in fractions distributed in highly structured SWNTs (25 wt%), with distribution in composition, length and structural quality (35 wt%) and with very defective and short tubes (25 wt%). The damages on the purified SWNT walls were characterized by the Raman scattering analysis.

Biological screening of Annonaceous Brazilian Medicinal Plants using Artemia salina (brine shrimp test).

Eighteen different extracts from five Annona species collected in Minas Gerais state, Brazil, were submitted to the brine shrimp lethality test in order to detect potential sources of novel cytotoxic, antitumor, pesticidal and anti-Trypanosoma cruzi compounds. All of the Annonaceous species tested showed good larvicidal activity as compared to a reference compounds and literature data.